Merge branch 'ucount-fixes-for-v5.15' of git://git.kernel.org/pub/scm/linux/kernel...
[linux-2.6-microblaze.git] / drivers / md / md.c
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3    md.c : Multiple Devices driver for Linux
4      Copyright (C) 1998, 1999, 2000 Ingo Molnar
5
6      completely rewritten, based on the MD driver code from Marc Zyngier
7
8    Changes:
9
10    - RAID-1/RAID-5 extensions by Miguel de Icaza, Gadi Oxman, Ingo Molnar
11    - RAID-6 extensions by H. Peter Anvin <hpa@zytor.com>
12    - boot support for linear and striped mode by Harald Hoyer <HarryH@Royal.Net>
13    - kerneld support by Boris Tobotras <boris@xtalk.msk.su>
14    - kmod support by: Cyrus Durgin
15    - RAID0 bugfixes: Mark Anthony Lisher <markal@iname.com>
16    - Devfs support by Richard Gooch <rgooch@atnf.csiro.au>
17
18    - lots of fixes and improvements to the RAID1/RAID5 and generic
19      RAID code (such as request based resynchronization):
20
21      Neil Brown <neilb@cse.unsw.edu.au>.
22
23    - persistent bitmap code
24      Copyright (C) 2003-2004, Paul Clements, SteelEye Technology, Inc.
25
26
27    Errors, Warnings, etc.
28    Please use:
29      pr_crit() for error conditions that risk data loss
30      pr_err() for error conditions that are unexpected, like an IO error
31          or internal inconsistency
32      pr_warn() for error conditions that could have been predicated, like
33          adding a device to an array when it has incompatible metadata
34      pr_info() for every interesting, very rare events, like an array starting
35          or stopping, or resync starting or stopping
36      pr_debug() for everything else.
37
38 */
39
40 #include <linux/sched/mm.h>
41 #include <linux/sched/signal.h>
42 #include <linux/kthread.h>
43 #include <linux/blkdev.h>
44 #include <linux/badblocks.h>
45 #include <linux/sysctl.h>
46 #include <linux/seq_file.h>
47 #include <linux/fs.h>
48 #include <linux/poll.h>
49 #include <linux/ctype.h>
50 #include <linux/string.h>
51 #include <linux/hdreg.h>
52 #include <linux/proc_fs.h>
53 #include <linux/random.h>
54 #include <linux/module.h>
55 #include <linux/reboot.h>
56 #include <linux/file.h>
57 #include <linux/compat.h>
58 #include <linux/delay.h>
59 #include <linux/raid/md_p.h>
60 #include <linux/raid/md_u.h>
61 #include <linux/raid/detect.h>
62 #include <linux/slab.h>
63 #include <linux/percpu-refcount.h>
64 #include <linux/part_stat.h>
65
66 #include <trace/events/block.h>
67 #include "md.h"
68 #include "md-bitmap.h"
69 #include "md-cluster.h"
70
71 /* pers_list is a list of registered personalities protected
72  * by pers_lock.
73  * pers_lock does extra service to protect accesses to
74  * mddev->thread when the mutex cannot be held.
75  */
76 static LIST_HEAD(pers_list);
77 static DEFINE_SPINLOCK(pers_lock);
78
79 static struct kobj_type md_ktype;
80
81 struct md_cluster_operations *md_cluster_ops;
82 EXPORT_SYMBOL(md_cluster_ops);
83 static struct module *md_cluster_mod;
84
85 static DECLARE_WAIT_QUEUE_HEAD(resync_wait);
86 static struct workqueue_struct *md_wq;
87 static struct workqueue_struct *md_misc_wq;
88 static struct workqueue_struct *md_rdev_misc_wq;
89
90 static int remove_and_add_spares(struct mddev *mddev,
91                                  struct md_rdev *this);
92 static void mddev_detach(struct mddev *mddev);
93
94 /*
95  * Default number of read corrections we'll attempt on an rdev
96  * before ejecting it from the array. We divide the read error
97  * count by 2 for every hour elapsed between read errors.
98  */
99 #define MD_DEFAULT_MAX_CORRECTED_READ_ERRORS 20
100 /* Default safemode delay: 200 msec */
101 #define DEFAULT_SAFEMODE_DELAY ((200 * HZ)/1000 +1)
102 /*
103  * Current RAID-1,4,5 parallel reconstruction 'guaranteed speed limit'
104  * is 1000 KB/sec, so the extra system load does not show up that much.
105  * Increase it if you want to have more _guaranteed_ speed. Note that
106  * the RAID driver will use the maximum available bandwidth if the IO
107  * subsystem is idle. There is also an 'absolute maximum' reconstruction
108  * speed limit - in case reconstruction slows down your system despite
109  * idle IO detection.
110  *
111  * you can change it via /proc/sys/dev/raid/speed_limit_min and _max.
112  * or /sys/block/mdX/md/sync_speed_{min,max}
113  */
114
115 static int sysctl_speed_limit_min = 1000;
116 static int sysctl_speed_limit_max = 200000;
117 static inline int speed_min(struct mddev *mddev)
118 {
119         return mddev->sync_speed_min ?
120                 mddev->sync_speed_min : sysctl_speed_limit_min;
121 }
122
123 static inline int speed_max(struct mddev *mddev)
124 {
125         return mddev->sync_speed_max ?
126                 mddev->sync_speed_max : sysctl_speed_limit_max;
127 }
128
129 static void rdev_uninit_serial(struct md_rdev *rdev)
130 {
131         if (!test_and_clear_bit(CollisionCheck, &rdev->flags))
132                 return;
133
134         kvfree(rdev->serial);
135         rdev->serial = NULL;
136 }
137
138 static void rdevs_uninit_serial(struct mddev *mddev)
139 {
140         struct md_rdev *rdev;
141
142         rdev_for_each(rdev, mddev)
143                 rdev_uninit_serial(rdev);
144 }
145
146 static int rdev_init_serial(struct md_rdev *rdev)
147 {
148         /* serial_nums equals with BARRIER_BUCKETS_NR */
149         int i, serial_nums = 1 << ((PAGE_SHIFT - ilog2(sizeof(atomic_t))));
150         struct serial_in_rdev *serial = NULL;
151
152         if (test_bit(CollisionCheck, &rdev->flags))
153                 return 0;
154
155         serial = kvmalloc(sizeof(struct serial_in_rdev) * serial_nums,
156                           GFP_KERNEL);
157         if (!serial)
158                 return -ENOMEM;
159
160         for (i = 0; i < serial_nums; i++) {
161                 struct serial_in_rdev *serial_tmp = &serial[i];
162
163                 spin_lock_init(&serial_tmp->serial_lock);
164                 serial_tmp->serial_rb = RB_ROOT_CACHED;
165                 init_waitqueue_head(&serial_tmp->serial_io_wait);
166         }
167
168         rdev->serial = serial;
169         set_bit(CollisionCheck, &rdev->flags);
170
171         return 0;
172 }
173
174 static int rdevs_init_serial(struct mddev *mddev)
175 {
176         struct md_rdev *rdev;
177         int ret = 0;
178
179         rdev_for_each(rdev, mddev) {
180                 ret = rdev_init_serial(rdev);
181                 if (ret)
182                         break;
183         }
184
185         /* Free all resources if pool is not existed */
186         if (ret && !mddev->serial_info_pool)
187                 rdevs_uninit_serial(mddev);
188
189         return ret;
190 }
191
192 /*
193  * rdev needs to enable serial stuffs if it meets the conditions:
194  * 1. it is multi-queue device flaged with writemostly.
195  * 2. the write-behind mode is enabled.
196  */
197 static int rdev_need_serial(struct md_rdev *rdev)
198 {
199         return (rdev && rdev->mddev->bitmap_info.max_write_behind > 0 &&
200                 rdev->bdev->bd_disk->queue->nr_hw_queues != 1 &&
201                 test_bit(WriteMostly, &rdev->flags));
202 }
203
204 /*
205  * Init resource for rdev(s), then create serial_info_pool if:
206  * 1. rdev is the first device which return true from rdev_enable_serial.
207  * 2. rdev is NULL, means we want to enable serialization for all rdevs.
208  */
209 void mddev_create_serial_pool(struct mddev *mddev, struct md_rdev *rdev,
210                               bool is_suspend)
211 {
212         int ret = 0;
213
214         if (rdev && !rdev_need_serial(rdev) &&
215             !test_bit(CollisionCheck, &rdev->flags))
216                 return;
217
218         if (!is_suspend)
219                 mddev_suspend(mddev);
220
221         if (!rdev)
222                 ret = rdevs_init_serial(mddev);
223         else
224                 ret = rdev_init_serial(rdev);
225         if (ret)
226                 goto abort;
227
228         if (mddev->serial_info_pool == NULL) {
229                 /*
230                  * already in memalloc noio context by
231                  * mddev_suspend()
232                  */
233                 mddev->serial_info_pool =
234                         mempool_create_kmalloc_pool(NR_SERIAL_INFOS,
235                                                 sizeof(struct serial_info));
236                 if (!mddev->serial_info_pool) {
237                         rdevs_uninit_serial(mddev);
238                         pr_err("can't alloc memory pool for serialization\n");
239                 }
240         }
241
242 abort:
243         if (!is_suspend)
244                 mddev_resume(mddev);
245 }
246
247 /*
248  * Free resource from rdev(s), and destroy serial_info_pool under conditions:
249  * 1. rdev is the last device flaged with CollisionCheck.
250  * 2. when bitmap is destroyed while policy is not enabled.
251  * 3. for disable policy, the pool is destroyed only when no rdev needs it.
252  */
253 void mddev_destroy_serial_pool(struct mddev *mddev, struct md_rdev *rdev,
254                                bool is_suspend)
255 {
256         if (rdev && !test_bit(CollisionCheck, &rdev->flags))
257                 return;
258
259         if (mddev->serial_info_pool) {
260                 struct md_rdev *temp;
261                 int num = 0; /* used to track if other rdevs need the pool */
262
263                 if (!is_suspend)
264                         mddev_suspend(mddev);
265                 rdev_for_each(temp, mddev) {
266                         if (!rdev) {
267                                 if (!mddev->serialize_policy ||
268                                     !rdev_need_serial(temp))
269                                         rdev_uninit_serial(temp);
270                                 else
271                                         num++;
272                         } else if (temp != rdev &&
273                                    test_bit(CollisionCheck, &temp->flags))
274                                 num++;
275                 }
276
277                 if (rdev)
278                         rdev_uninit_serial(rdev);
279
280                 if (num)
281                         pr_info("The mempool could be used by other devices\n");
282                 else {
283                         mempool_destroy(mddev->serial_info_pool);
284                         mddev->serial_info_pool = NULL;
285                 }
286                 if (!is_suspend)
287                         mddev_resume(mddev);
288         }
289 }
290
291 static struct ctl_table_header *raid_table_header;
292
293 static struct ctl_table raid_table[] = {
294         {
295                 .procname       = "speed_limit_min",
296                 .data           = &sysctl_speed_limit_min,
297                 .maxlen         = sizeof(int),
298                 .mode           = S_IRUGO|S_IWUSR,
299                 .proc_handler   = proc_dointvec,
300         },
301         {
302                 .procname       = "speed_limit_max",
303                 .data           = &sysctl_speed_limit_max,
304                 .maxlen         = sizeof(int),
305                 .mode           = S_IRUGO|S_IWUSR,
306                 .proc_handler   = proc_dointvec,
307         },
308         { }
309 };
310
311 static struct ctl_table raid_dir_table[] = {
312         {
313                 .procname       = "raid",
314                 .maxlen         = 0,
315                 .mode           = S_IRUGO|S_IXUGO,
316                 .child          = raid_table,
317         },
318         { }
319 };
320
321 static struct ctl_table raid_root_table[] = {
322         {
323                 .procname       = "dev",
324                 .maxlen         = 0,
325                 .mode           = 0555,
326                 .child          = raid_dir_table,
327         },
328         {  }
329 };
330
331 static int start_readonly;
332
333 /*
334  * The original mechanism for creating an md device is to create
335  * a device node in /dev and to open it.  This causes races with device-close.
336  * The preferred method is to write to the "new_array" module parameter.
337  * This can avoid races.
338  * Setting create_on_open to false disables the original mechanism
339  * so all the races disappear.
340  */
341 static bool create_on_open = true;
342
343 /*
344  * We have a system wide 'event count' that is incremented
345  * on any 'interesting' event, and readers of /proc/mdstat
346  * can use 'poll' or 'select' to find out when the event
347  * count increases.
348  *
349  * Events are:
350  *  start array, stop array, error, add device, remove device,
351  *  start build, activate spare
352  */
353 static DECLARE_WAIT_QUEUE_HEAD(md_event_waiters);
354 static atomic_t md_event_count;
355 void md_new_event(struct mddev *mddev)
356 {
357         atomic_inc(&md_event_count);
358         wake_up(&md_event_waiters);
359 }
360 EXPORT_SYMBOL_GPL(md_new_event);
361
362 /*
363  * Enables to iterate over all existing md arrays
364  * all_mddevs_lock protects this list.
365  */
366 static LIST_HEAD(all_mddevs);
367 static DEFINE_SPINLOCK(all_mddevs_lock);
368
369 /*
370  * iterates through all used mddevs in the system.
371  * We take care to grab the all_mddevs_lock whenever navigating
372  * the list, and to always hold a refcount when unlocked.
373  * Any code which breaks out of this loop while own
374  * a reference to the current mddev and must mddev_put it.
375  */
376 #define for_each_mddev(_mddev,_tmp)                                     \
377                                                                         \
378         for (({ spin_lock(&all_mddevs_lock);                            \
379                 _tmp = all_mddevs.next;                                 \
380                 _mddev = NULL;});                                       \
381              ({ if (_tmp != &all_mddevs)                                \
382                         mddev_get(list_entry(_tmp, struct mddev, all_mddevs));\
383                 spin_unlock(&all_mddevs_lock);                          \
384                 if (_mddev) mddev_put(_mddev);                          \
385                 _mddev = list_entry(_tmp, struct mddev, all_mddevs);    \
386                 _tmp != &all_mddevs;});                                 \
387              ({ spin_lock(&all_mddevs_lock);                            \
388                 _tmp = _tmp->next;})                                    \
389                 )
390
391 /* Rather than calling directly into the personality make_request function,
392  * IO requests come here first so that we can check if the device is
393  * being suspended pending a reconfiguration.
394  * We hold a refcount over the call to ->make_request.  By the time that
395  * call has finished, the bio has been linked into some internal structure
396  * and so is visible to ->quiesce(), so we don't need the refcount any more.
397  */
398 static bool is_suspended(struct mddev *mddev, struct bio *bio)
399 {
400         if (mddev->suspended)
401                 return true;
402         if (bio_data_dir(bio) != WRITE)
403                 return false;
404         if (mddev->suspend_lo >= mddev->suspend_hi)
405                 return false;
406         if (bio->bi_iter.bi_sector >= mddev->suspend_hi)
407                 return false;
408         if (bio_end_sector(bio) < mddev->suspend_lo)
409                 return false;
410         return true;
411 }
412
413 void md_handle_request(struct mddev *mddev, struct bio *bio)
414 {
415 check_suspended:
416         rcu_read_lock();
417         if (is_suspended(mddev, bio)) {
418                 DEFINE_WAIT(__wait);
419                 for (;;) {
420                         prepare_to_wait(&mddev->sb_wait, &__wait,
421                                         TASK_UNINTERRUPTIBLE);
422                         if (!is_suspended(mddev, bio))
423                                 break;
424                         rcu_read_unlock();
425                         schedule();
426                         rcu_read_lock();
427                 }
428                 finish_wait(&mddev->sb_wait, &__wait);
429         }
430         atomic_inc(&mddev->active_io);
431         rcu_read_unlock();
432
433         if (!mddev->pers->make_request(mddev, bio)) {
434                 atomic_dec(&mddev->active_io);
435                 wake_up(&mddev->sb_wait);
436                 goto check_suspended;
437         }
438
439         if (atomic_dec_and_test(&mddev->active_io) && mddev->suspended)
440                 wake_up(&mddev->sb_wait);
441 }
442 EXPORT_SYMBOL(md_handle_request);
443
444 static blk_qc_t md_submit_bio(struct bio *bio)
445 {
446         const int rw = bio_data_dir(bio);
447         struct mddev *mddev = bio->bi_bdev->bd_disk->private_data;
448
449         if (mddev == NULL || mddev->pers == NULL) {
450                 bio_io_error(bio);
451                 return BLK_QC_T_NONE;
452         }
453
454         if (unlikely(test_bit(MD_BROKEN, &mddev->flags)) && (rw == WRITE)) {
455                 bio_io_error(bio);
456                 return BLK_QC_T_NONE;
457         }
458
459         blk_queue_split(&bio);
460
461         if (mddev->ro == 1 && unlikely(rw == WRITE)) {
462                 if (bio_sectors(bio) != 0)
463                         bio->bi_status = BLK_STS_IOERR;
464                 bio_endio(bio);
465                 return BLK_QC_T_NONE;
466         }
467
468         /* bio could be mergeable after passing to underlayer */
469         bio->bi_opf &= ~REQ_NOMERGE;
470
471         md_handle_request(mddev, bio);
472
473         return BLK_QC_T_NONE;
474 }
475
476 /* mddev_suspend makes sure no new requests are submitted
477  * to the device, and that any requests that have been submitted
478  * are completely handled.
479  * Once mddev_detach() is called and completes, the module will be
480  * completely unused.
481  */
482 void mddev_suspend(struct mddev *mddev)
483 {
484         WARN_ON_ONCE(mddev->thread && current == mddev->thread->tsk);
485         lockdep_assert_held(&mddev->reconfig_mutex);
486         if (mddev->suspended++)
487                 return;
488         synchronize_rcu();
489         wake_up(&mddev->sb_wait);
490         set_bit(MD_ALLOW_SB_UPDATE, &mddev->flags);
491         smp_mb__after_atomic();
492         wait_event(mddev->sb_wait, atomic_read(&mddev->active_io) == 0);
493         mddev->pers->quiesce(mddev, 1);
494         clear_bit_unlock(MD_ALLOW_SB_UPDATE, &mddev->flags);
495         wait_event(mddev->sb_wait, !test_bit(MD_UPDATING_SB, &mddev->flags));
496
497         del_timer_sync(&mddev->safemode_timer);
498         /* restrict memory reclaim I/O during raid array is suspend */
499         mddev->noio_flag = memalloc_noio_save();
500 }
501 EXPORT_SYMBOL_GPL(mddev_suspend);
502
503 void mddev_resume(struct mddev *mddev)
504 {
505         /* entred the memalloc scope from mddev_suspend() */
506         memalloc_noio_restore(mddev->noio_flag);
507         lockdep_assert_held(&mddev->reconfig_mutex);
508         if (--mddev->suspended)
509                 return;
510         wake_up(&mddev->sb_wait);
511         mddev->pers->quiesce(mddev, 0);
512
513         set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
514         md_wakeup_thread(mddev->thread);
515         md_wakeup_thread(mddev->sync_thread); /* possibly kick off a reshape */
516 }
517 EXPORT_SYMBOL_GPL(mddev_resume);
518
519 /*
520  * Generic flush handling for md
521  */
522
523 static void md_end_flush(struct bio *bio)
524 {
525         struct md_rdev *rdev = bio->bi_private;
526         struct mddev *mddev = rdev->mddev;
527
528         rdev_dec_pending(rdev, mddev);
529
530         if (atomic_dec_and_test(&mddev->flush_pending)) {
531                 /* The pre-request flush has finished */
532                 queue_work(md_wq, &mddev->flush_work);
533         }
534         bio_put(bio);
535 }
536
537 static void md_submit_flush_data(struct work_struct *ws);
538
539 static void submit_flushes(struct work_struct *ws)
540 {
541         struct mddev *mddev = container_of(ws, struct mddev, flush_work);
542         struct md_rdev *rdev;
543
544         mddev->start_flush = ktime_get_boottime();
545         INIT_WORK(&mddev->flush_work, md_submit_flush_data);
546         atomic_set(&mddev->flush_pending, 1);
547         rcu_read_lock();
548         rdev_for_each_rcu(rdev, mddev)
549                 if (rdev->raid_disk >= 0 &&
550                     !test_bit(Faulty, &rdev->flags)) {
551                         /* Take two references, one is dropped
552                          * when request finishes, one after
553                          * we reclaim rcu_read_lock
554                          */
555                         struct bio *bi;
556                         atomic_inc(&rdev->nr_pending);
557                         atomic_inc(&rdev->nr_pending);
558                         rcu_read_unlock();
559                         bi = bio_alloc_bioset(GFP_NOIO, 0, &mddev->bio_set);
560                         bi->bi_end_io = md_end_flush;
561                         bi->bi_private = rdev;
562                         bio_set_dev(bi, rdev->bdev);
563                         bi->bi_opf = REQ_OP_WRITE | REQ_PREFLUSH;
564                         atomic_inc(&mddev->flush_pending);
565                         submit_bio(bi);
566                         rcu_read_lock();
567                         rdev_dec_pending(rdev, mddev);
568                 }
569         rcu_read_unlock();
570         if (atomic_dec_and_test(&mddev->flush_pending))
571                 queue_work(md_wq, &mddev->flush_work);
572 }
573
574 static void md_submit_flush_data(struct work_struct *ws)
575 {
576         struct mddev *mddev = container_of(ws, struct mddev, flush_work);
577         struct bio *bio = mddev->flush_bio;
578
579         /*
580          * must reset flush_bio before calling into md_handle_request to avoid a
581          * deadlock, because other bios passed md_handle_request suspend check
582          * could wait for this and below md_handle_request could wait for those
583          * bios because of suspend check
584          */
585         spin_lock_irq(&mddev->lock);
586         mddev->prev_flush_start = mddev->start_flush;
587         mddev->flush_bio = NULL;
588         spin_unlock_irq(&mddev->lock);
589         wake_up(&mddev->sb_wait);
590
591         if (bio->bi_iter.bi_size == 0) {
592                 /* an empty barrier - all done */
593                 bio_endio(bio);
594         } else {
595                 bio->bi_opf &= ~REQ_PREFLUSH;
596                 md_handle_request(mddev, bio);
597         }
598 }
599
600 /*
601  * Manages consolidation of flushes and submitting any flushes needed for
602  * a bio with REQ_PREFLUSH.  Returns true if the bio is finished or is
603  * being finished in another context.  Returns false if the flushing is
604  * complete but still needs the I/O portion of the bio to be processed.
605  */
606 bool md_flush_request(struct mddev *mddev, struct bio *bio)
607 {
608         ktime_t req_start = ktime_get_boottime();
609         spin_lock_irq(&mddev->lock);
610         /* flush requests wait until ongoing flush completes,
611          * hence coalescing all the pending requests.
612          */
613         wait_event_lock_irq(mddev->sb_wait,
614                             !mddev->flush_bio ||
615                             ktime_before(req_start, mddev->prev_flush_start),
616                             mddev->lock);
617         /* new request after previous flush is completed */
618         if (ktime_after(req_start, mddev->prev_flush_start)) {
619                 WARN_ON(mddev->flush_bio);
620                 mddev->flush_bio = bio;
621                 bio = NULL;
622         }
623         spin_unlock_irq(&mddev->lock);
624
625         if (!bio) {
626                 INIT_WORK(&mddev->flush_work, submit_flushes);
627                 queue_work(md_wq, &mddev->flush_work);
628         } else {
629                 /* flush was performed for some other bio while we waited. */
630                 if (bio->bi_iter.bi_size == 0)
631                         /* an empty barrier - all done */
632                         bio_endio(bio);
633                 else {
634                         bio->bi_opf &= ~REQ_PREFLUSH;
635                         return false;
636                 }
637         }
638         return true;
639 }
640 EXPORT_SYMBOL(md_flush_request);
641
642 static inline struct mddev *mddev_get(struct mddev *mddev)
643 {
644         atomic_inc(&mddev->active);
645         return mddev;
646 }
647
648 static void mddev_delayed_delete(struct work_struct *ws);
649
650 static void mddev_put(struct mddev *mddev)
651 {
652         if (!atomic_dec_and_lock(&mddev->active, &all_mddevs_lock))
653                 return;
654         if (!mddev->raid_disks && list_empty(&mddev->disks) &&
655             mddev->ctime == 0 && !mddev->hold_active) {
656                 /* Array is not configured at all, and not held active,
657                  * so destroy it */
658                 list_del_init(&mddev->all_mddevs);
659
660                 /*
661                  * Call queue_work inside the spinlock so that
662                  * flush_workqueue() after mddev_find will succeed in waiting
663                  * for the work to be done.
664                  */
665                 INIT_WORK(&mddev->del_work, mddev_delayed_delete);
666                 queue_work(md_misc_wq, &mddev->del_work);
667         }
668         spin_unlock(&all_mddevs_lock);
669 }
670
671 static void md_safemode_timeout(struct timer_list *t);
672
673 void mddev_init(struct mddev *mddev)
674 {
675         kobject_init(&mddev->kobj, &md_ktype);
676         mutex_init(&mddev->open_mutex);
677         mutex_init(&mddev->reconfig_mutex);
678         mutex_init(&mddev->bitmap_info.mutex);
679         INIT_LIST_HEAD(&mddev->disks);
680         INIT_LIST_HEAD(&mddev->all_mddevs);
681         timer_setup(&mddev->safemode_timer, md_safemode_timeout, 0);
682         atomic_set(&mddev->active, 1);
683         atomic_set(&mddev->openers, 0);
684         atomic_set(&mddev->active_io, 0);
685         spin_lock_init(&mddev->lock);
686         atomic_set(&mddev->flush_pending, 0);
687         init_waitqueue_head(&mddev->sb_wait);
688         init_waitqueue_head(&mddev->recovery_wait);
689         mddev->reshape_position = MaxSector;
690         mddev->reshape_backwards = 0;
691         mddev->last_sync_action = "none";
692         mddev->resync_min = 0;
693         mddev->resync_max = MaxSector;
694         mddev->level = LEVEL_NONE;
695 }
696 EXPORT_SYMBOL_GPL(mddev_init);
697
698 static struct mddev *mddev_find_locked(dev_t unit)
699 {
700         struct mddev *mddev;
701
702         list_for_each_entry(mddev, &all_mddevs, all_mddevs)
703                 if (mddev->unit == unit)
704                         return mddev;
705
706         return NULL;
707 }
708
709 /* find an unused unit number */
710 static dev_t mddev_alloc_unit(void)
711 {
712         static int next_minor = 512;
713         int start = next_minor;
714         bool is_free = 0;
715         dev_t dev = 0;
716
717         while (!is_free) {
718                 dev = MKDEV(MD_MAJOR, next_minor);
719                 next_minor++;
720                 if (next_minor > MINORMASK)
721                         next_minor = 0;
722                 if (next_minor == start)
723                         return 0;               /* Oh dear, all in use. */
724                 is_free = !mddev_find_locked(dev);
725         }
726
727         return dev;
728 }
729
730 static struct mddev *mddev_find(dev_t unit)
731 {
732         struct mddev *mddev;
733
734         if (MAJOR(unit) != MD_MAJOR)
735                 unit &= ~((1 << MdpMinorShift) - 1);
736
737         spin_lock(&all_mddevs_lock);
738         mddev = mddev_find_locked(unit);
739         if (mddev)
740                 mddev_get(mddev);
741         spin_unlock(&all_mddevs_lock);
742
743         return mddev;
744 }
745
746 static struct mddev *mddev_alloc(dev_t unit)
747 {
748         struct mddev *new;
749         int error;
750
751         if (unit && MAJOR(unit) != MD_MAJOR)
752                 unit &= ~((1 << MdpMinorShift) - 1);
753
754         new = kzalloc(sizeof(*new), GFP_KERNEL);
755         if (!new)
756                 return ERR_PTR(-ENOMEM);
757         mddev_init(new);
758
759         spin_lock(&all_mddevs_lock);
760         if (unit) {
761                 error = -EEXIST;
762                 if (mddev_find_locked(unit))
763                         goto out_free_new;
764                 new->unit = unit;
765                 if (MAJOR(unit) == MD_MAJOR)
766                         new->md_minor = MINOR(unit);
767                 else
768                         new->md_minor = MINOR(unit) >> MdpMinorShift;
769                 new->hold_active = UNTIL_IOCTL;
770         } else {
771                 error = -ENODEV;
772                 new->unit = mddev_alloc_unit();
773                 if (!new->unit)
774                         goto out_free_new;
775                 new->md_minor = MINOR(new->unit);
776                 new->hold_active = UNTIL_STOP;
777         }
778
779         list_add(&new->all_mddevs, &all_mddevs);
780         spin_unlock(&all_mddevs_lock);
781         return new;
782 out_free_new:
783         spin_unlock(&all_mddevs_lock);
784         kfree(new);
785         return ERR_PTR(error);
786 }
787
788 static const struct attribute_group md_redundancy_group;
789
790 void mddev_unlock(struct mddev *mddev)
791 {
792         if (mddev->to_remove) {
793                 /* These cannot be removed under reconfig_mutex as
794                  * an access to the files will try to take reconfig_mutex
795                  * while holding the file unremovable, which leads to
796                  * a deadlock.
797                  * So hold set sysfs_active while the remove in happeing,
798                  * and anything else which might set ->to_remove or my
799                  * otherwise change the sysfs namespace will fail with
800                  * -EBUSY if sysfs_active is still set.
801                  * We set sysfs_active under reconfig_mutex and elsewhere
802                  * test it under the same mutex to ensure its correct value
803                  * is seen.
804                  */
805                 const struct attribute_group *to_remove = mddev->to_remove;
806                 mddev->to_remove = NULL;
807                 mddev->sysfs_active = 1;
808                 mutex_unlock(&mddev->reconfig_mutex);
809
810                 if (mddev->kobj.sd) {
811                         if (to_remove != &md_redundancy_group)
812                                 sysfs_remove_group(&mddev->kobj, to_remove);
813                         if (mddev->pers == NULL ||
814                             mddev->pers->sync_request == NULL) {
815                                 sysfs_remove_group(&mddev->kobj, &md_redundancy_group);
816                                 if (mddev->sysfs_action)
817                                         sysfs_put(mddev->sysfs_action);
818                                 if (mddev->sysfs_completed)
819                                         sysfs_put(mddev->sysfs_completed);
820                                 if (mddev->sysfs_degraded)
821                                         sysfs_put(mddev->sysfs_degraded);
822                                 mddev->sysfs_action = NULL;
823                                 mddev->sysfs_completed = NULL;
824                                 mddev->sysfs_degraded = NULL;
825                         }
826                 }
827                 mddev->sysfs_active = 0;
828         } else
829                 mutex_unlock(&mddev->reconfig_mutex);
830
831         /* As we've dropped the mutex we need a spinlock to
832          * make sure the thread doesn't disappear
833          */
834         spin_lock(&pers_lock);
835         md_wakeup_thread(mddev->thread);
836         wake_up(&mddev->sb_wait);
837         spin_unlock(&pers_lock);
838 }
839 EXPORT_SYMBOL_GPL(mddev_unlock);
840
841 struct md_rdev *md_find_rdev_nr_rcu(struct mddev *mddev, int nr)
842 {
843         struct md_rdev *rdev;
844
845         rdev_for_each_rcu(rdev, mddev)
846                 if (rdev->desc_nr == nr)
847                         return rdev;
848
849         return NULL;
850 }
851 EXPORT_SYMBOL_GPL(md_find_rdev_nr_rcu);
852
853 static struct md_rdev *find_rdev(struct mddev *mddev, dev_t dev)
854 {
855         struct md_rdev *rdev;
856
857         rdev_for_each(rdev, mddev)
858                 if (rdev->bdev->bd_dev == dev)
859                         return rdev;
860
861         return NULL;
862 }
863
864 struct md_rdev *md_find_rdev_rcu(struct mddev *mddev, dev_t dev)
865 {
866         struct md_rdev *rdev;
867
868         rdev_for_each_rcu(rdev, mddev)
869                 if (rdev->bdev->bd_dev == dev)
870                         return rdev;
871
872         return NULL;
873 }
874 EXPORT_SYMBOL_GPL(md_find_rdev_rcu);
875
876 static struct md_personality *find_pers(int level, char *clevel)
877 {
878         struct md_personality *pers;
879         list_for_each_entry(pers, &pers_list, list) {
880                 if (level != LEVEL_NONE && pers->level == level)
881                         return pers;
882                 if (strcmp(pers->name, clevel)==0)
883                         return pers;
884         }
885         return NULL;
886 }
887
888 /* return the offset of the super block in 512byte sectors */
889 static inline sector_t calc_dev_sboffset(struct md_rdev *rdev)
890 {
891         sector_t num_sectors = i_size_read(rdev->bdev->bd_inode) / 512;
892         return MD_NEW_SIZE_SECTORS(num_sectors);
893 }
894
895 static int alloc_disk_sb(struct md_rdev *rdev)
896 {
897         rdev->sb_page = alloc_page(GFP_KERNEL);
898         if (!rdev->sb_page)
899                 return -ENOMEM;
900         return 0;
901 }
902
903 void md_rdev_clear(struct md_rdev *rdev)
904 {
905         if (rdev->sb_page) {
906                 put_page(rdev->sb_page);
907                 rdev->sb_loaded = 0;
908                 rdev->sb_page = NULL;
909                 rdev->sb_start = 0;
910                 rdev->sectors = 0;
911         }
912         if (rdev->bb_page) {
913                 put_page(rdev->bb_page);
914                 rdev->bb_page = NULL;
915         }
916         badblocks_exit(&rdev->badblocks);
917 }
918 EXPORT_SYMBOL_GPL(md_rdev_clear);
919
920 static void super_written(struct bio *bio)
921 {
922         struct md_rdev *rdev = bio->bi_private;
923         struct mddev *mddev = rdev->mddev;
924
925         if (bio->bi_status) {
926                 pr_err("md: %s gets error=%d\n", __func__,
927                        blk_status_to_errno(bio->bi_status));
928                 md_error(mddev, rdev);
929                 if (!test_bit(Faulty, &rdev->flags)
930                     && (bio->bi_opf & MD_FAILFAST)) {
931                         set_bit(MD_SB_NEED_REWRITE, &mddev->sb_flags);
932                         set_bit(LastDev, &rdev->flags);
933                 }
934         } else
935                 clear_bit(LastDev, &rdev->flags);
936
937         if (atomic_dec_and_test(&mddev->pending_writes))
938                 wake_up(&mddev->sb_wait);
939         rdev_dec_pending(rdev, mddev);
940         bio_put(bio);
941 }
942
943 void md_super_write(struct mddev *mddev, struct md_rdev *rdev,
944                    sector_t sector, int size, struct page *page)
945 {
946         /* write first size bytes of page to sector of rdev
947          * Increment mddev->pending_writes before returning
948          * and decrement it on completion, waking up sb_wait
949          * if zero is reached.
950          * If an error occurred, call md_error
951          */
952         struct bio *bio;
953         int ff = 0;
954
955         if (!page)
956                 return;
957
958         if (test_bit(Faulty, &rdev->flags))
959                 return;
960
961         bio = bio_alloc_bioset(GFP_NOIO, 1, &mddev->sync_set);
962
963         atomic_inc(&rdev->nr_pending);
964
965         bio_set_dev(bio, rdev->meta_bdev ? rdev->meta_bdev : rdev->bdev);
966         bio->bi_iter.bi_sector = sector;
967         bio_add_page(bio, page, size, 0);
968         bio->bi_private = rdev;
969         bio->bi_end_io = super_written;
970
971         if (test_bit(MD_FAILFAST_SUPPORTED, &mddev->flags) &&
972             test_bit(FailFast, &rdev->flags) &&
973             !test_bit(LastDev, &rdev->flags))
974                 ff = MD_FAILFAST;
975         bio->bi_opf = REQ_OP_WRITE | REQ_SYNC | REQ_PREFLUSH | REQ_FUA | ff;
976
977         atomic_inc(&mddev->pending_writes);
978         submit_bio(bio);
979 }
980
981 int md_super_wait(struct mddev *mddev)
982 {
983         /* wait for all superblock writes that were scheduled to complete */
984         wait_event(mddev->sb_wait, atomic_read(&mddev->pending_writes)==0);
985         if (test_and_clear_bit(MD_SB_NEED_REWRITE, &mddev->sb_flags))
986                 return -EAGAIN;
987         return 0;
988 }
989
990 int sync_page_io(struct md_rdev *rdev, sector_t sector, int size,
991                  struct page *page, int op, int op_flags, bool metadata_op)
992 {
993         struct bio bio;
994         struct bio_vec bvec;
995
996         bio_init(&bio, &bvec, 1);
997
998         if (metadata_op && rdev->meta_bdev)
999                 bio_set_dev(&bio, rdev->meta_bdev);
1000         else
1001                 bio_set_dev(&bio, rdev->bdev);
1002         bio.bi_opf = op | op_flags;
1003         if (metadata_op)
1004                 bio.bi_iter.bi_sector = sector + rdev->sb_start;
1005         else if (rdev->mddev->reshape_position != MaxSector &&
1006                  (rdev->mddev->reshape_backwards ==
1007                   (sector >= rdev->mddev->reshape_position)))
1008                 bio.bi_iter.bi_sector = sector + rdev->new_data_offset;
1009         else
1010                 bio.bi_iter.bi_sector = sector + rdev->data_offset;
1011         bio_add_page(&bio, page, size, 0);
1012
1013         submit_bio_wait(&bio);
1014
1015         return !bio.bi_status;
1016 }
1017 EXPORT_SYMBOL_GPL(sync_page_io);
1018
1019 static int read_disk_sb(struct md_rdev *rdev, int size)
1020 {
1021         char b[BDEVNAME_SIZE];
1022
1023         if (rdev->sb_loaded)
1024                 return 0;
1025
1026         if (!sync_page_io(rdev, 0, size, rdev->sb_page, REQ_OP_READ, 0, true))
1027                 goto fail;
1028         rdev->sb_loaded = 1;
1029         return 0;
1030
1031 fail:
1032         pr_err("md: disabled device %s, could not read superblock.\n",
1033                bdevname(rdev->bdev,b));
1034         return -EINVAL;
1035 }
1036
1037 static int md_uuid_equal(mdp_super_t *sb1, mdp_super_t *sb2)
1038 {
1039         return  sb1->set_uuid0 == sb2->set_uuid0 &&
1040                 sb1->set_uuid1 == sb2->set_uuid1 &&
1041                 sb1->set_uuid2 == sb2->set_uuid2 &&
1042                 sb1->set_uuid3 == sb2->set_uuid3;
1043 }
1044
1045 static int md_sb_equal(mdp_super_t *sb1, mdp_super_t *sb2)
1046 {
1047         int ret;
1048         mdp_super_t *tmp1, *tmp2;
1049
1050         tmp1 = kmalloc(sizeof(*tmp1),GFP_KERNEL);
1051         tmp2 = kmalloc(sizeof(*tmp2),GFP_KERNEL);
1052
1053         if (!tmp1 || !tmp2) {
1054                 ret = 0;
1055                 goto abort;
1056         }
1057
1058         *tmp1 = *sb1;
1059         *tmp2 = *sb2;
1060
1061         /*
1062          * nr_disks is not constant
1063          */
1064         tmp1->nr_disks = 0;
1065         tmp2->nr_disks = 0;
1066
1067         ret = (memcmp(tmp1, tmp2, MD_SB_GENERIC_CONSTANT_WORDS * 4) == 0);
1068 abort:
1069         kfree(tmp1);
1070         kfree(tmp2);
1071         return ret;
1072 }
1073
1074 static u32 md_csum_fold(u32 csum)
1075 {
1076         csum = (csum & 0xffff) + (csum >> 16);
1077         return (csum & 0xffff) + (csum >> 16);
1078 }
1079
1080 static unsigned int calc_sb_csum(mdp_super_t *sb)
1081 {
1082         u64 newcsum = 0;
1083         u32 *sb32 = (u32*)sb;
1084         int i;
1085         unsigned int disk_csum, csum;
1086
1087         disk_csum = sb->sb_csum;
1088         sb->sb_csum = 0;
1089
1090         for (i = 0; i < MD_SB_BYTES/4 ; i++)
1091                 newcsum += sb32[i];
1092         csum = (newcsum & 0xffffffff) + (newcsum>>32);
1093
1094 #ifdef CONFIG_ALPHA
1095         /* This used to use csum_partial, which was wrong for several
1096          * reasons including that different results are returned on
1097          * different architectures.  It isn't critical that we get exactly
1098          * the same return value as before (we always csum_fold before
1099          * testing, and that removes any differences).  However as we
1100          * know that csum_partial always returned a 16bit value on
1101          * alphas, do a fold to maximise conformity to previous behaviour.
1102          */
1103         sb->sb_csum = md_csum_fold(disk_csum);
1104 #else
1105         sb->sb_csum = disk_csum;
1106 #endif
1107         return csum;
1108 }
1109
1110 /*
1111  * Handle superblock details.
1112  * We want to be able to handle multiple superblock formats
1113  * so we have a common interface to them all, and an array of
1114  * different handlers.
1115  * We rely on user-space to write the initial superblock, and support
1116  * reading and updating of superblocks.
1117  * Interface methods are:
1118  *   int load_super(struct md_rdev *dev, struct md_rdev *refdev, int minor_version)
1119  *      loads and validates a superblock on dev.
1120  *      if refdev != NULL, compare superblocks on both devices
1121  *    Return:
1122  *      0 - dev has a superblock that is compatible with refdev
1123  *      1 - dev has a superblock that is compatible and newer than refdev
1124  *          so dev should be used as the refdev in future
1125  *     -EINVAL superblock incompatible or invalid
1126  *     -othererror e.g. -EIO
1127  *
1128  *   int validate_super(struct mddev *mddev, struct md_rdev *dev)
1129  *      Verify that dev is acceptable into mddev.
1130  *       The first time, mddev->raid_disks will be 0, and data from
1131  *       dev should be merged in.  Subsequent calls check that dev
1132  *       is new enough.  Return 0 or -EINVAL
1133  *
1134  *   void sync_super(struct mddev *mddev, struct md_rdev *dev)
1135  *     Update the superblock for rdev with data in mddev
1136  *     This does not write to disc.
1137  *
1138  */
1139
1140 struct super_type  {
1141         char                *name;
1142         struct module       *owner;
1143         int                 (*load_super)(struct md_rdev *rdev,
1144                                           struct md_rdev *refdev,
1145                                           int minor_version);
1146         int                 (*validate_super)(struct mddev *mddev,
1147                                               struct md_rdev *rdev);
1148         void                (*sync_super)(struct mddev *mddev,
1149                                           struct md_rdev *rdev);
1150         unsigned long long  (*rdev_size_change)(struct md_rdev *rdev,
1151                                                 sector_t num_sectors);
1152         int                 (*allow_new_offset)(struct md_rdev *rdev,
1153                                                 unsigned long long new_offset);
1154 };
1155
1156 /*
1157  * Check that the given mddev has no bitmap.
1158  *
1159  * This function is called from the run method of all personalities that do not
1160  * support bitmaps. It prints an error message and returns non-zero if mddev
1161  * has a bitmap. Otherwise, it returns 0.
1162  *
1163  */
1164 int md_check_no_bitmap(struct mddev *mddev)
1165 {
1166         if (!mddev->bitmap_info.file && !mddev->bitmap_info.offset)
1167                 return 0;
1168         pr_warn("%s: bitmaps are not supported for %s\n",
1169                 mdname(mddev), mddev->pers->name);
1170         return 1;
1171 }
1172 EXPORT_SYMBOL(md_check_no_bitmap);
1173
1174 /*
1175  * load_super for 0.90.0
1176  */
1177 static int super_90_load(struct md_rdev *rdev, struct md_rdev *refdev, int minor_version)
1178 {
1179         char b[BDEVNAME_SIZE], b2[BDEVNAME_SIZE];
1180         mdp_super_t *sb;
1181         int ret;
1182         bool spare_disk = true;
1183
1184         /*
1185          * Calculate the position of the superblock (512byte sectors),
1186          * it's at the end of the disk.
1187          *
1188          * It also happens to be a multiple of 4Kb.
1189          */
1190         rdev->sb_start = calc_dev_sboffset(rdev);
1191
1192         ret = read_disk_sb(rdev, MD_SB_BYTES);
1193         if (ret)
1194                 return ret;
1195
1196         ret = -EINVAL;
1197
1198         bdevname(rdev->bdev, b);
1199         sb = page_address(rdev->sb_page);
1200
1201         if (sb->md_magic != MD_SB_MAGIC) {
1202                 pr_warn("md: invalid raid superblock magic on %s\n", b);
1203                 goto abort;
1204         }
1205
1206         if (sb->major_version != 0 ||
1207             sb->minor_version < 90 ||
1208             sb->minor_version > 91) {
1209                 pr_warn("Bad version number %d.%d on %s\n",
1210                         sb->major_version, sb->minor_version, b);
1211                 goto abort;
1212         }
1213
1214         if (sb->raid_disks <= 0)
1215                 goto abort;
1216
1217         if (md_csum_fold(calc_sb_csum(sb)) != md_csum_fold(sb->sb_csum)) {
1218                 pr_warn("md: invalid superblock checksum on %s\n", b);
1219                 goto abort;
1220         }
1221
1222         rdev->preferred_minor = sb->md_minor;
1223         rdev->data_offset = 0;
1224         rdev->new_data_offset = 0;
1225         rdev->sb_size = MD_SB_BYTES;
1226         rdev->badblocks.shift = -1;
1227
1228         if (sb->level == LEVEL_MULTIPATH)
1229                 rdev->desc_nr = -1;
1230         else
1231                 rdev->desc_nr = sb->this_disk.number;
1232
1233         /* not spare disk, or LEVEL_MULTIPATH */
1234         if (sb->level == LEVEL_MULTIPATH ||
1235                 (rdev->desc_nr >= 0 &&
1236                  rdev->desc_nr < MD_SB_DISKS &&
1237                  sb->disks[rdev->desc_nr].state &
1238                  ((1<<MD_DISK_SYNC) | (1 << MD_DISK_ACTIVE))))
1239                 spare_disk = false;
1240
1241         if (!refdev) {
1242                 if (!spare_disk)
1243                         ret = 1;
1244                 else
1245                         ret = 0;
1246         } else {
1247                 __u64 ev1, ev2;
1248                 mdp_super_t *refsb = page_address(refdev->sb_page);
1249                 if (!md_uuid_equal(refsb, sb)) {
1250                         pr_warn("md: %s has different UUID to %s\n",
1251                                 b, bdevname(refdev->bdev,b2));
1252                         goto abort;
1253                 }
1254                 if (!md_sb_equal(refsb, sb)) {
1255                         pr_warn("md: %s has same UUID but different superblock to %s\n",
1256                                 b, bdevname(refdev->bdev, b2));
1257                         goto abort;
1258                 }
1259                 ev1 = md_event(sb);
1260                 ev2 = md_event(refsb);
1261
1262                 if (!spare_disk && ev1 > ev2)
1263                         ret = 1;
1264                 else
1265                         ret = 0;
1266         }
1267         rdev->sectors = rdev->sb_start;
1268         /* Limit to 4TB as metadata cannot record more than that.
1269          * (not needed for Linear and RAID0 as metadata doesn't
1270          * record this size)
1271          */
1272         if ((u64)rdev->sectors >= (2ULL << 32) && sb->level >= 1)
1273                 rdev->sectors = (sector_t)(2ULL << 32) - 2;
1274
1275         if (rdev->sectors < ((sector_t)sb->size) * 2 && sb->level >= 1)
1276                 /* "this cannot possibly happen" ... */
1277                 ret = -EINVAL;
1278
1279  abort:
1280         return ret;
1281 }
1282
1283 /*
1284  * validate_super for 0.90.0
1285  */
1286 static int super_90_validate(struct mddev *mddev, struct md_rdev *rdev)
1287 {
1288         mdp_disk_t *desc;
1289         mdp_super_t *sb = page_address(rdev->sb_page);
1290         __u64 ev1 = md_event(sb);
1291
1292         rdev->raid_disk = -1;
1293         clear_bit(Faulty, &rdev->flags);
1294         clear_bit(In_sync, &rdev->flags);
1295         clear_bit(Bitmap_sync, &rdev->flags);
1296         clear_bit(WriteMostly, &rdev->flags);
1297
1298         if (mddev->raid_disks == 0) {
1299                 mddev->major_version = 0;
1300                 mddev->minor_version = sb->minor_version;
1301                 mddev->patch_version = sb->patch_version;
1302                 mddev->external = 0;
1303                 mddev->chunk_sectors = sb->chunk_size >> 9;
1304                 mddev->ctime = sb->ctime;
1305                 mddev->utime = sb->utime;
1306                 mddev->level = sb->level;
1307                 mddev->clevel[0] = 0;
1308                 mddev->layout = sb->layout;
1309                 mddev->raid_disks = sb->raid_disks;
1310                 mddev->dev_sectors = ((sector_t)sb->size) * 2;
1311                 mddev->events = ev1;
1312                 mddev->bitmap_info.offset = 0;
1313                 mddev->bitmap_info.space = 0;
1314                 /* bitmap can use 60 K after the 4K superblocks */
1315                 mddev->bitmap_info.default_offset = MD_SB_BYTES >> 9;
1316                 mddev->bitmap_info.default_space = 64*2 - (MD_SB_BYTES >> 9);
1317                 mddev->reshape_backwards = 0;
1318
1319                 if (mddev->minor_version >= 91) {
1320                         mddev->reshape_position = sb->reshape_position;
1321                         mddev->delta_disks = sb->delta_disks;
1322                         mddev->new_level = sb->new_level;
1323                         mddev->new_layout = sb->new_layout;
1324                         mddev->new_chunk_sectors = sb->new_chunk >> 9;
1325                         if (mddev->delta_disks < 0)
1326                                 mddev->reshape_backwards = 1;
1327                 } else {
1328                         mddev->reshape_position = MaxSector;
1329                         mddev->delta_disks = 0;
1330                         mddev->new_level = mddev->level;
1331                         mddev->new_layout = mddev->layout;
1332                         mddev->new_chunk_sectors = mddev->chunk_sectors;
1333                 }
1334                 if (mddev->level == 0)
1335                         mddev->layout = -1;
1336
1337                 if (sb->state & (1<<MD_SB_CLEAN))
1338                         mddev->recovery_cp = MaxSector;
1339                 else {
1340                         if (sb->events_hi == sb->cp_events_hi &&
1341                                 sb->events_lo == sb->cp_events_lo) {
1342                                 mddev->recovery_cp = sb->recovery_cp;
1343                         } else
1344                                 mddev->recovery_cp = 0;
1345                 }
1346
1347                 memcpy(mddev->uuid+0, &sb->set_uuid0, 4);
1348                 memcpy(mddev->uuid+4, &sb->set_uuid1, 4);
1349                 memcpy(mddev->uuid+8, &sb->set_uuid2, 4);
1350                 memcpy(mddev->uuid+12,&sb->set_uuid3, 4);
1351
1352                 mddev->max_disks = MD_SB_DISKS;
1353
1354                 if (sb->state & (1<<MD_SB_BITMAP_PRESENT) &&
1355                     mddev->bitmap_info.file == NULL) {
1356                         mddev->bitmap_info.offset =
1357                                 mddev->bitmap_info.default_offset;
1358                         mddev->bitmap_info.space =
1359                                 mddev->bitmap_info.default_space;
1360                 }
1361
1362         } else if (mddev->pers == NULL) {
1363                 /* Insist on good event counter while assembling, except
1364                  * for spares (which don't need an event count) */
1365                 ++ev1;
1366                 if (sb->disks[rdev->desc_nr].state & (
1367                             (1<<MD_DISK_SYNC) | (1 << MD_DISK_ACTIVE)))
1368                         if (ev1 < mddev->events)
1369                                 return -EINVAL;
1370         } else if (mddev->bitmap) {
1371                 /* if adding to array with a bitmap, then we can accept an
1372                  * older device ... but not too old.
1373                  */
1374                 if (ev1 < mddev->bitmap->events_cleared)
1375                         return 0;
1376                 if (ev1 < mddev->events)
1377                         set_bit(Bitmap_sync, &rdev->flags);
1378         } else {
1379                 if (ev1 < mddev->events)
1380                         /* just a hot-add of a new device, leave raid_disk at -1 */
1381                         return 0;
1382         }
1383
1384         if (mddev->level != LEVEL_MULTIPATH) {
1385                 desc = sb->disks + rdev->desc_nr;
1386
1387                 if (desc->state & (1<<MD_DISK_FAULTY))
1388                         set_bit(Faulty, &rdev->flags);
1389                 else if (desc->state & (1<<MD_DISK_SYNC) /* &&
1390                             desc->raid_disk < mddev->raid_disks */) {
1391                         set_bit(In_sync, &rdev->flags);
1392                         rdev->raid_disk = desc->raid_disk;
1393                         rdev->saved_raid_disk = desc->raid_disk;
1394                 } else if (desc->state & (1<<MD_DISK_ACTIVE)) {
1395                         /* active but not in sync implies recovery up to
1396                          * reshape position.  We don't know exactly where
1397                          * that is, so set to zero for now */
1398                         if (mddev->minor_version >= 91) {
1399                                 rdev->recovery_offset = 0;
1400                                 rdev->raid_disk = desc->raid_disk;
1401                         }
1402                 }
1403                 if (desc->state & (1<<MD_DISK_WRITEMOSTLY))
1404                         set_bit(WriteMostly, &rdev->flags);
1405                 if (desc->state & (1<<MD_DISK_FAILFAST))
1406                         set_bit(FailFast, &rdev->flags);
1407         } else /* MULTIPATH are always insync */
1408                 set_bit(In_sync, &rdev->flags);
1409         return 0;
1410 }
1411
1412 /*
1413  * sync_super for 0.90.0
1414  */
1415 static void super_90_sync(struct mddev *mddev, struct md_rdev *rdev)
1416 {
1417         mdp_super_t *sb;
1418         struct md_rdev *rdev2;
1419         int next_spare = mddev->raid_disks;
1420
1421         /* make rdev->sb match mddev data..
1422          *
1423          * 1/ zero out disks
1424          * 2/ Add info for each disk, keeping track of highest desc_nr (next_spare);
1425          * 3/ any empty disks < next_spare become removed
1426          *
1427          * disks[0] gets initialised to REMOVED because
1428          * we cannot be sure from other fields if it has
1429          * been initialised or not.
1430          */
1431         int i;
1432         int active=0, working=0,failed=0,spare=0,nr_disks=0;
1433
1434         rdev->sb_size = MD_SB_BYTES;
1435
1436         sb = page_address(rdev->sb_page);
1437
1438         memset(sb, 0, sizeof(*sb));
1439
1440         sb->md_magic = MD_SB_MAGIC;
1441         sb->major_version = mddev->major_version;
1442         sb->patch_version = mddev->patch_version;
1443         sb->gvalid_words  = 0; /* ignored */
1444         memcpy(&sb->set_uuid0, mddev->uuid+0, 4);
1445         memcpy(&sb->set_uuid1, mddev->uuid+4, 4);
1446         memcpy(&sb->set_uuid2, mddev->uuid+8, 4);
1447         memcpy(&sb->set_uuid3, mddev->uuid+12,4);
1448
1449         sb->ctime = clamp_t(time64_t, mddev->ctime, 0, U32_MAX);
1450         sb->level = mddev->level;
1451         sb->size = mddev->dev_sectors / 2;
1452         sb->raid_disks = mddev->raid_disks;
1453         sb->md_minor = mddev->md_minor;
1454         sb->not_persistent = 0;
1455         sb->utime = clamp_t(time64_t, mddev->utime, 0, U32_MAX);
1456         sb->state = 0;
1457         sb->events_hi = (mddev->events>>32);
1458         sb->events_lo = (u32)mddev->events;
1459
1460         if (mddev->reshape_position == MaxSector)
1461                 sb->minor_version = 90;
1462         else {
1463                 sb->minor_version = 91;
1464                 sb->reshape_position = mddev->reshape_position;
1465                 sb->new_level = mddev->new_level;
1466                 sb->delta_disks = mddev->delta_disks;
1467                 sb->new_layout = mddev->new_layout;
1468                 sb->new_chunk = mddev->new_chunk_sectors << 9;
1469         }
1470         mddev->minor_version = sb->minor_version;
1471         if (mddev->in_sync)
1472         {
1473                 sb->recovery_cp = mddev->recovery_cp;
1474                 sb->cp_events_hi = (mddev->events>>32);
1475                 sb->cp_events_lo = (u32)mddev->events;
1476                 if (mddev->recovery_cp == MaxSector)
1477                         sb->state = (1<< MD_SB_CLEAN);
1478         } else
1479                 sb->recovery_cp = 0;
1480
1481         sb->layout = mddev->layout;
1482         sb->chunk_size = mddev->chunk_sectors << 9;
1483
1484         if (mddev->bitmap && mddev->bitmap_info.file == NULL)
1485                 sb->state |= (1<<MD_SB_BITMAP_PRESENT);
1486
1487         sb->disks[0].state = (1<<MD_DISK_REMOVED);
1488         rdev_for_each(rdev2, mddev) {
1489                 mdp_disk_t *d;
1490                 int desc_nr;
1491                 int is_active = test_bit(In_sync, &rdev2->flags);
1492
1493                 if (rdev2->raid_disk >= 0 &&
1494                     sb->minor_version >= 91)
1495                         /* we have nowhere to store the recovery_offset,
1496                          * but if it is not below the reshape_position,
1497                          * we can piggy-back on that.
1498                          */
1499                         is_active = 1;
1500                 if (rdev2->raid_disk < 0 ||
1501                     test_bit(Faulty, &rdev2->flags))
1502                         is_active = 0;
1503                 if (is_active)
1504                         desc_nr = rdev2->raid_disk;
1505                 else
1506                         desc_nr = next_spare++;
1507                 rdev2->desc_nr = desc_nr;
1508                 d = &sb->disks[rdev2->desc_nr];
1509                 nr_disks++;
1510                 d->number = rdev2->desc_nr;
1511                 d->major = MAJOR(rdev2->bdev->bd_dev);
1512                 d->minor = MINOR(rdev2->bdev->bd_dev);
1513                 if (is_active)
1514                         d->raid_disk = rdev2->raid_disk;
1515                 else
1516                         d->raid_disk = rdev2->desc_nr; /* compatibility */
1517                 if (test_bit(Faulty, &rdev2->flags))
1518                         d->state = (1<<MD_DISK_FAULTY);
1519                 else if (is_active) {
1520                         d->state = (1<<MD_DISK_ACTIVE);
1521                         if (test_bit(In_sync, &rdev2->flags))
1522                                 d->state |= (1<<MD_DISK_SYNC);
1523                         active++;
1524                         working++;
1525                 } else {
1526                         d->state = 0;
1527                         spare++;
1528                         working++;
1529                 }
1530                 if (test_bit(WriteMostly, &rdev2->flags))
1531                         d->state |= (1<<MD_DISK_WRITEMOSTLY);
1532                 if (test_bit(FailFast, &rdev2->flags))
1533                         d->state |= (1<<MD_DISK_FAILFAST);
1534         }
1535         /* now set the "removed" and "faulty" bits on any missing devices */
1536         for (i=0 ; i < mddev->raid_disks ; i++) {
1537                 mdp_disk_t *d = &sb->disks[i];
1538                 if (d->state == 0 && d->number == 0) {
1539                         d->number = i;
1540                         d->raid_disk = i;
1541                         d->state = (1<<MD_DISK_REMOVED);
1542                         d->state |= (1<<MD_DISK_FAULTY);
1543                         failed++;
1544                 }
1545         }
1546         sb->nr_disks = nr_disks;
1547         sb->active_disks = active;
1548         sb->working_disks = working;
1549         sb->failed_disks = failed;
1550         sb->spare_disks = spare;
1551
1552         sb->this_disk = sb->disks[rdev->desc_nr];
1553         sb->sb_csum = calc_sb_csum(sb);
1554 }
1555
1556 /*
1557  * rdev_size_change for 0.90.0
1558  */
1559 static unsigned long long
1560 super_90_rdev_size_change(struct md_rdev *rdev, sector_t num_sectors)
1561 {
1562         if (num_sectors && num_sectors < rdev->mddev->dev_sectors)
1563                 return 0; /* component must fit device */
1564         if (rdev->mddev->bitmap_info.offset)
1565                 return 0; /* can't move bitmap */
1566         rdev->sb_start = calc_dev_sboffset(rdev);
1567         if (!num_sectors || num_sectors > rdev->sb_start)
1568                 num_sectors = rdev->sb_start;
1569         /* Limit to 4TB as metadata cannot record more than that.
1570          * 4TB == 2^32 KB, or 2*2^32 sectors.
1571          */
1572         if ((u64)num_sectors >= (2ULL << 32) && rdev->mddev->level >= 1)
1573                 num_sectors = (sector_t)(2ULL << 32) - 2;
1574         do {
1575                 md_super_write(rdev->mddev, rdev, rdev->sb_start, rdev->sb_size,
1576                        rdev->sb_page);
1577         } while (md_super_wait(rdev->mddev) < 0);
1578         return num_sectors;
1579 }
1580
1581 static int
1582 super_90_allow_new_offset(struct md_rdev *rdev, unsigned long long new_offset)
1583 {
1584         /* non-zero offset changes not possible with v0.90 */
1585         return new_offset == 0;
1586 }
1587
1588 /*
1589  * version 1 superblock
1590  */
1591
1592 static __le32 calc_sb_1_csum(struct mdp_superblock_1 *sb)
1593 {
1594         __le32 disk_csum;
1595         u32 csum;
1596         unsigned long long newcsum;
1597         int size = 256 + le32_to_cpu(sb->max_dev)*2;
1598         __le32 *isuper = (__le32*)sb;
1599
1600         disk_csum = sb->sb_csum;
1601         sb->sb_csum = 0;
1602         newcsum = 0;
1603         for (; size >= 4; size -= 4)
1604                 newcsum += le32_to_cpu(*isuper++);
1605
1606         if (size == 2)
1607                 newcsum += le16_to_cpu(*(__le16*) isuper);
1608
1609         csum = (newcsum & 0xffffffff) + (newcsum >> 32);
1610         sb->sb_csum = disk_csum;
1611         return cpu_to_le32(csum);
1612 }
1613
1614 static int super_1_load(struct md_rdev *rdev, struct md_rdev *refdev, int minor_version)
1615 {
1616         struct mdp_superblock_1 *sb;
1617         int ret;
1618         sector_t sb_start;
1619         sector_t sectors;
1620         char b[BDEVNAME_SIZE], b2[BDEVNAME_SIZE];
1621         int bmask;
1622         bool spare_disk = true;
1623
1624         /*
1625          * Calculate the position of the superblock in 512byte sectors.
1626          * It is always aligned to a 4K boundary and
1627          * depeding on minor_version, it can be:
1628          * 0: At least 8K, but less than 12K, from end of device
1629          * 1: At start of device
1630          * 2: 4K from start of device.
1631          */
1632         switch(minor_version) {
1633         case 0:
1634                 sb_start = i_size_read(rdev->bdev->bd_inode) >> 9;
1635                 sb_start -= 8*2;
1636                 sb_start &= ~(sector_t)(4*2-1);
1637                 break;
1638         case 1:
1639                 sb_start = 0;
1640                 break;
1641         case 2:
1642                 sb_start = 8;
1643                 break;
1644         default:
1645                 return -EINVAL;
1646         }
1647         rdev->sb_start = sb_start;
1648
1649         /* superblock is rarely larger than 1K, but it can be larger,
1650          * and it is safe to read 4k, so we do that
1651          */
1652         ret = read_disk_sb(rdev, 4096);
1653         if (ret) return ret;
1654
1655         sb = page_address(rdev->sb_page);
1656
1657         if (sb->magic != cpu_to_le32(MD_SB_MAGIC) ||
1658             sb->major_version != cpu_to_le32(1) ||
1659             le32_to_cpu(sb->max_dev) > (4096-256)/2 ||
1660             le64_to_cpu(sb->super_offset) != rdev->sb_start ||
1661             (le32_to_cpu(sb->feature_map) & ~MD_FEATURE_ALL) != 0)
1662                 return -EINVAL;
1663
1664         if (calc_sb_1_csum(sb) != sb->sb_csum) {
1665                 pr_warn("md: invalid superblock checksum on %s\n",
1666                         bdevname(rdev->bdev,b));
1667                 return -EINVAL;
1668         }
1669         if (le64_to_cpu(sb->data_size) < 10) {
1670                 pr_warn("md: data_size too small on %s\n",
1671                         bdevname(rdev->bdev,b));
1672                 return -EINVAL;
1673         }
1674         if (sb->pad0 ||
1675             sb->pad3[0] ||
1676             memcmp(sb->pad3, sb->pad3+1, sizeof(sb->pad3) - sizeof(sb->pad3[1])))
1677                 /* Some padding is non-zero, might be a new feature */
1678                 return -EINVAL;
1679
1680         rdev->preferred_minor = 0xffff;
1681         rdev->data_offset = le64_to_cpu(sb->data_offset);
1682         rdev->new_data_offset = rdev->data_offset;
1683         if ((le32_to_cpu(sb->feature_map) & MD_FEATURE_RESHAPE_ACTIVE) &&
1684             (le32_to_cpu(sb->feature_map) & MD_FEATURE_NEW_OFFSET))
1685                 rdev->new_data_offset += (s32)le32_to_cpu(sb->new_offset);
1686         atomic_set(&rdev->corrected_errors, le32_to_cpu(sb->cnt_corrected_read));
1687
1688         rdev->sb_size = le32_to_cpu(sb->max_dev) * 2 + 256;
1689         bmask = queue_logical_block_size(rdev->bdev->bd_disk->queue)-1;
1690         if (rdev->sb_size & bmask)
1691                 rdev->sb_size = (rdev->sb_size | bmask) + 1;
1692
1693         if (minor_version
1694             && rdev->data_offset < sb_start + (rdev->sb_size/512))
1695                 return -EINVAL;
1696         if (minor_version
1697             && rdev->new_data_offset < sb_start + (rdev->sb_size/512))
1698                 return -EINVAL;
1699
1700         if (sb->level == cpu_to_le32(LEVEL_MULTIPATH))
1701                 rdev->desc_nr = -1;
1702         else
1703                 rdev->desc_nr = le32_to_cpu(sb->dev_number);
1704
1705         if (!rdev->bb_page) {
1706                 rdev->bb_page = alloc_page(GFP_KERNEL);
1707                 if (!rdev->bb_page)
1708                         return -ENOMEM;
1709         }
1710         if ((le32_to_cpu(sb->feature_map) & MD_FEATURE_BAD_BLOCKS) &&
1711             rdev->badblocks.count == 0) {
1712                 /* need to load the bad block list.
1713                  * Currently we limit it to one page.
1714                  */
1715                 s32 offset;
1716                 sector_t bb_sector;
1717                 __le64 *bbp;
1718                 int i;
1719                 int sectors = le16_to_cpu(sb->bblog_size);
1720                 if (sectors > (PAGE_SIZE / 512))
1721                         return -EINVAL;
1722                 offset = le32_to_cpu(sb->bblog_offset);
1723                 if (offset == 0)
1724                         return -EINVAL;
1725                 bb_sector = (long long)offset;
1726                 if (!sync_page_io(rdev, bb_sector, sectors << 9,
1727                                   rdev->bb_page, REQ_OP_READ, 0, true))
1728                         return -EIO;
1729                 bbp = (__le64 *)page_address(rdev->bb_page);
1730                 rdev->badblocks.shift = sb->bblog_shift;
1731                 for (i = 0 ; i < (sectors << (9-3)) ; i++, bbp++) {
1732                         u64 bb = le64_to_cpu(*bbp);
1733                         int count = bb & (0x3ff);
1734                         u64 sector = bb >> 10;
1735                         sector <<= sb->bblog_shift;
1736                         count <<= sb->bblog_shift;
1737                         if (bb + 1 == 0)
1738                                 break;
1739                         if (badblocks_set(&rdev->badblocks, sector, count, 1))
1740                                 return -EINVAL;
1741                 }
1742         } else if (sb->bblog_offset != 0)
1743                 rdev->badblocks.shift = 0;
1744
1745         if ((le32_to_cpu(sb->feature_map) &
1746             (MD_FEATURE_PPL | MD_FEATURE_MULTIPLE_PPLS))) {
1747                 rdev->ppl.offset = (__s16)le16_to_cpu(sb->ppl.offset);
1748                 rdev->ppl.size = le16_to_cpu(sb->ppl.size);
1749                 rdev->ppl.sector = rdev->sb_start + rdev->ppl.offset;
1750         }
1751
1752         if ((le32_to_cpu(sb->feature_map) & MD_FEATURE_RAID0_LAYOUT) &&
1753             sb->level != 0)
1754                 return -EINVAL;
1755
1756         /* not spare disk, or LEVEL_MULTIPATH */
1757         if (sb->level == cpu_to_le32(LEVEL_MULTIPATH) ||
1758                 (rdev->desc_nr >= 0 &&
1759                 rdev->desc_nr < le32_to_cpu(sb->max_dev) &&
1760                 (le16_to_cpu(sb->dev_roles[rdev->desc_nr]) < MD_DISK_ROLE_MAX ||
1761                  le16_to_cpu(sb->dev_roles[rdev->desc_nr]) == MD_DISK_ROLE_JOURNAL)))
1762                 spare_disk = false;
1763
1764         if (!refdev) {
1765                 if (!spare_disk)
1766                         ret = 1;
1767                 else
1768                         ret = 0;
1769         } else {
1770                 __u64 ev1, ev2;
1771                 struct mdp_superblock_1 *refsb = page_address(refdev->sb_page);
1772
1773                 if (memcmp(sb->set_uuid, refsb->set_uuid, 16) != 0 ||
1774                     sb->level != refsb->level ||
1775                     sb->layout != refsb->layout ||
1776                     sb->chunksize != refsb->chunksize) {
1777                         pr_warn("md: %s has strangely different superblock to %s\n",
1778                                 bdevname(rdev->bdev,b),
1779                                 bdevname(refdev->bdev,b2));
1780                         return -EINVAL;
1781                 }
1782                 ev1 = le64_to_cpu(sb->events);
1783                 ev2 = le64_to_cpu(refsb->events);
1784
1785                 if (!spare_disk && ev1 > ev2)
1786                         ret = 1;
1787                 else
1788                         ret = 0;
1789         }
1790         if (minor_version) {
1791                 sectors = (i_size_read(rdev->bdev->bd_inode) >> 9);
1792                 sectors -= rdev->data_offset;
1793         } else
1794                 sectors = rdev->sb_start;
1795         if (sectors < le64_to_cpu(sb->data_size))
1796                 return -EINVAL;
1797         rdev->sectors = le64_to_cpu(sb->data_size);
1798         return ret;
1799 }
1800
1801 static int super_1_validate(struct mddev *mddev, struct md_rdev *rdev)
1802 {
1803         struct mdp_superblock_1 *sb = page_address(rdev->sb_page);
1804         __u64 ev1 = le64_to_cpu(sb->events);
1805
1806         rdev->raid_disk = -1;
1807         clear_bit(Faulty, &rdev->flags);
1808         clear_bit(In_sync, &rdev->flags);
1809         clear_bit(Bitmap_sync, &rdev->flags);
1810         clear_bit(WriteMostly, &rdev->flags);
1811
1812         if (mddev->raid_disks == 0) {
1813                 mddev->major_version = 1;
1814                 mddev->patch_version = 0;
1815                 mddev->external = 0;
1816                 mddev->chunk_sectors = le32_to_cpu(sb->chunksize);
1817                 mddev->ctime = le64_to_cpu(sb->ctime);
1818                 mddev->utime = le64_to_cpu(sb->utime);
1819                 mddev->level = le32_to_cpu(sb->level);
1820                 mddev->clevel[0] = 0;
1821                 mddev->layout = le32_to_cpu(sb->layout);
1822                 mddev->raid_disks = le32_to_cpu(sb->raid_disks);
1823                 mddev->dev_sectors = le64_to_cpu(sb->size);
1824                 mddev->events = ev1;
1825                 mddev->bitmap_info.offset = 0;
1826                 mddev->bitmap_info.space = 0;
1827                 /* Default location for bitmap is 1K after superblock
1828                  * using 3K - total of 4K
1829                  */
1830                 mddev->bitmap_info.default_offset = 1024 >> 9;
1831                 mddev->bitmap_info.default_space = (4096-1024) >> 9;
1832                 mddev->reshape_backwards = 0;
1833
1834                 mddev->recovery_cp = le64_to_cpu(sb->resync_offset);
1835                 memcpy(mddev->uuid, sb->set_uuid, 16);
1836
1837                 mddev->max_disks =  (4096-256)/2;
1838
1839                 if ((le32_to_cpu(sb->feature_map) & MD_FEATURE_BITMAP_OFFSET) &&
1840                     mddev->bitmap_info.file == NULL) {
1841                         mddev->bitmap_info.offset =
1842                                 (__s32)le32_to_cpu(sb->bitmap_offset);
1843                         /* Metadata doesn't record how much space is available.
1844                          * For 1.0, we assume we can use up to the superblock
1845                          * if before, else to 4K beyond superblock.
1846                          * For others, assume no change is possible.
1847                          */
1848                         if (mddev->minor_version > 0)
1849                                 mddev->bitmap_info.space = 0;
1850                         else if (mddev->bitmap_info.offset > 0)
1851                                 mddev->bitmap_info.space =
1852                                         8 - mddev->bitmap_info.offset;
1853                         else
1854                                 mddev->bitmap_info.space =
1855                                         -mddev->bitmap_info.offset;
1856                 }
1857
1858                 if ((le32_to_cpu(sb->feature_map) & MD_FEATURE_RESHAPE_ACTIVE)) {
1859                         mddev->reshape_position = le64_to_cpu(sb->reshape_position);
1860                         mddev->delta_disks = le32_to_cpu(sb->delta_disks);
1861                         mddev->new_level = le32_to_cpu(sb->new_level);
1862                         mddev->new_layout = le32_to_cpu(sb->new_layout);
1863                         mddev->new_chunk_sectors = le32_to_cpu(sb->new_chunk);
1864                         if (mddev->delta_disks < 0 ||
1865                             (mddev->delta_disks == 0 &&
1866                              (le32_to_cpu(sb->feature_map)
1867                               & MD_FEATURE_RESHAPE_BACKWARDS)))
1868                                 mddev->reshape_backwards = 1;
1869                 } else {
1870                         mddev->reshape_position = MaxSector;
1871                         mddev->delta_disks = 0;
1872                         mddev->new_level = mddev->level;
1873                         mddev->new_layout = mddev->layout;
1874                         mddev->new_chunk_sectors = mddev->chunk_sectors;
1875                 }
1876
1877                 if (mddev->level == 0 &&
1878                     !(le32_to_cpu(sb->feature_map) & MD_FEATURE_RAID0_LAYOUT))
1879                         mddev->layout = -1;
1880
1881                 if (le32_to_cpu(sb->feature_map) & MD_FEATURE_JOURNAL)
1882                         set_bit(MD_HAS_JOURNAL, &mddev->flags);
1883
1884                 if (le32_to_cpu(sb->feature_map) &
1885                     (MD_FEATURE_PPL | MD_FEATURE_MULTIPLE_PPLS)) {
1886                         if (le32_to_cpu(sb->feature_map) &
1887                             (MD_FEATURE_BITMAP_OFFSET | MD_FEATURE_JOURNAL))
1888                                 return -EINVAL;
1889                         if ((le32_to_cpu(sb->feature_map) & MD_FEATURE_PPL) &&
1890                             (le32_to_cpu(sb->feature_map) &
1891                                             MD_FEATURE_MULTIPLE_PPLS))
1892                                 return -EINVAL;
1893                         set_bit(MD_HAS_PPL, &mddev->flags);
1894                 }
1895         } else if (mddev->pers == NULL) {
1896                 /* Insist of good event counter while assembling, except for
1897                  * spares (which don't need an event count) */
1898                 ++ev1;
1899                 if (rdev->desc_nr >= 0 &&
1900                     rdev->desc_nr < le32_to_cpu(sb->max_dev) &&
1901                     (le16_to_cpu(sb->dev_roles[rdev->desc_nr]) < MD_DISK_ROLE_MAX ||
1902                      le16_to_cpu(sb->dev_roles[rdev->desc_nr]) == MD_DISK_ROLE_JOURNAL))
1903                         if (ev1 < mddev->events)
1904                                 return -EINVAL;
1905         } else if (mddev->bitmap) {
1906                 /* If adding to array with a bitmap, then we can accept an
1907                  * older device, but not too old.
1908                  */
1909                 if (ev1 < mddev->bitmap->events_cleared)
1910                         return 0;
1911                 if (ev1 < mddev->events)
1912                         set_bit(Bitmap_sync, &rdev->flags);
1913         } else {
1914                 if (ev1 < mddev->events)
1915                         /* just a hot-add of a new device, leave raid_disk at -1 */
1916                         return 0;
1917         }
1918         if (mddev->level != LEVEL_MULTIPATH) {
1919                 int role;
1920                 if (rdev->desc_nr < 0 ||
1921                     rdev->desc_nr >= le32_to_cpu(sb->max_dev)) {
1922                         role = MD_DISK_ROLE_SPARE;
1923                         rdev->desc_nr = -1;
1924                 } else
1925                         role = le16_to_cpu(sb->dev_roles[rdev->desc_nr]);
1926                 switch(role) {
1927                 case MD_DISK_ROLE_SPARE: /* spare */
1928                         break;
1929                 case MD_DISK_ROLE_FAULTY: /* faulty */
1930                         set_bit(Faulty, &rdev->flags);
1931                         break;
1932                 case MD_DISK_ROLE_JOURNAL: /* journal device */
1933                         if (!(le32_to_cpu(sb->feature_map) & MD_FEATURE_JOURNAL)) {
1934                                 /* journal device without journal feature */
1935                                 pr_warn("md: journal device provided without journal feature, ignoring the device\n");
1936                                 return -EINVAL;
1937                         }
1938                         set_bit(Journal, &rdev->flags);
1939                         rdev->journal_tail = le64_to_cpu(sb->journal_tail);
1940                         rdev->raid_disk = 0;
1941                         break;
1942                 default:
1943                         rdev->saved_raid_disk = role;
1944                         if ((le32_to_cpu(sb->feature_map) &
1945                              MD_FEATURE_RECOVERY_OFFSET)) {
1946                                 rdev->recovery_offset = le64_to_cpu(sb->recovery_offset);
1947                                 if (!(le32_to_cpu(sb->feature_map) &
1948                                       MD_FEATURE_RECOVERY_BITMAP))
1949                                         rdev->saved_raid_disk = -1;
1950                         } else {
1951                                 /*
1952                                  * If the array is FROZEN, then the device can't
1953                                  * be in_sync with rest of array.
1954                                  */
1955                                 if (!test_bit(MD_RECOVERY_FROZEN,
1956                                               &mddev->recovery))
1957                                         set_bit(In_sync, &rdev->flags);
1958                         }
1959                         rdev->raid_disk = role;
1960                         break;
1961                 }
1962                 if (sb->devflags & WriteMostly1)
1963                         set_bit(WriteMostly, &rdev->flags);
1964                 if (sb->devflags & FailFast1)
1965                         set_bit(FailFast, &rdev->flags);
1966                 if (le32_to_cpu(sb->feature_map) & MD_FEATURE_REPLACEMENT)
1967                         set_bit(Replacement, &rdev->flags);
1968         } else /* MULTIPATH are always insync */
1969                 set_bit(In_sync, &rdev->flags);
1970
1971         return 0;
1972 }
1973
1974 static void super_1_sync(struct mddev *mddev, struct md_rdev *rdev)
1975 {
1976         struct mdp_superblock_1 *sb;
1977         struct md_rdev *rdev2;
1978         int max_dev, i;
1979         /* make rdev->sb match mddev and rdev data. */
1980
1981         sb = page_address(rdev->sb_page);
1982
1983         sb->feature_map = 0;
1984         sb->pad0 = 0;
1985         sb->recovery_offset = cpu_to_le64(0);
1986         memset(sb->pad3, 0, sizeof(sb->pad3));
1987
1988         sb->utime = cpu_to_le64((__u64)mddev->utime);
1989         sb->events = cpu_to_le64(mddev->events);
1990         if (mddev->in_sync)
1991                 sb->resync_offset = cpu_to_le64(mddev->recovery_cp);
1992         else if (test_bit(MD_JOURNAL_CLEAN, &mddev->flags))
1993                 sb->resync_offset = cpu_to_le64(MaxSector);
1994         else
1995                 sb->resync_offset = cpu_to_le64(0);
1996
1997         sb->cnt_corrected_read = cpu_to_le32(atomic_read(&rdev->corrected_errors));
1998
1999         sb->raid_disks = cpu_to_le32(mddev->raid_disks);
2000         sb->size = cpu_to_le64(mddev->dev_sectors);
2001         sb->chunksize = cpu_to_le32(mddev->chunk_sectors);
2002         sb->level = cpu_to_le32(mddev->level);
2003         sb->layout = cpu_to_le32(mddev->layout);
2004         if (test_bit(FailFast, &rdev->flags))
2005                 sb->devflags |= FailFast1;
2006         else
2007                 sb->devflags &= ~FailFast1;
2008
2009         if (test_bit(WriteMostly, &rdev->flags))
2010                 sb->devflags |= WriteMostly1;
2011         else
2012                 sb->devflags &= ~WriteMostly1;
2013         sb->data_offset = cpu_to_le64(rdev->data_offset);
2014         sb->data_size = cpu_to_le64(rdev->sectors);
2015
2016         if (mddev->bitmap && mddev->bitmap_info.file == NULL) {
2017                 sb->bitmap_offset = cpu_to_le32((__u32)mddev->bitmap_info.offset);
2018                 sb->feature_map = cpu_to_le32(MD_FEATURE_BITMAP_OFFSET);
2019         }
2020
2021         if (rdev->raid_disk >= 0 && !test_bit(Journal, &rdev->flags) &&
2022             !test_bit(In_sync, &rdev->flags)) {
2023                 sb->feature_map |=
2024                         cpu_to_le32(MD_FEATURE_RECOVERY_OFFSET);
2025                 sb->recovery_offset =
2026                         cpu_to_le64(rdev->recovery_offset);
2027                 if (rdev->saved_raid_disk >= 0 && mddev->bitmap)
2028                         sb->feature_map |=
2029                                 cpu_to_le32(MD_FEATURE_RECOVERY_BITMAP);
2030         }
2031         /* Note: recovery_offset and journal_tail share space  */
2032         if (test_bit(Journal, &rdev->flags))
2033                 sb->journal_tail = cpu_to_le64(rdev->journal_tail);
2034         if (test_bit(Replacement, &rdev->flags))
2035                 sb->feature_map |=
2036                         cpu_to_le32(MD_FEATURE_REPLACEMENT);
2037
2038         if (mddev->reshape_position != MaxSector) {
2039                 sb->feature_map |= cpu_to_le32(MD_FEATURE_RESHAPE_ACTIVE);
2040                 sb->reshape_position = cpu_to_le64(mddev->reshape_position);
2041                 sb->new_layout = cpu_to_le32(mddev->new_layout);
2042                 sb->delta_disks = cpu_to_le32(mddev->delta_disks);
2043                 sb->new_level = cpu_to_le32(mddev->new_level);
2044                 sb->new_chunk = cpu_to_le32(mddev->new_chunk_sectors);
2045                 if (mddev->delta_disks == 0 &&
2046                     mddev->reshape_backwards)
2047                         sb->feature_map
2048                                 |= cpu_to_le32(MD_FEATURE_RESHAPE_BACKWARDS);
2049                 if (rdev->new_data_offset != rdev->data_offset) {
2050                         sb->feature_map
2051                                 |= cpu_to_le32(MD_FEATURE_NEW_OFFSET);
2052                         sb->new_offset = cpu_to_le32((__u32)(rdev->new_data_offset
2053                                                              - rdev->data_offset));
2054                 }
2055         }
2056
2057         if (mddev_is_clustered(mddev))
2058                 sb->feature_map |= cpu_to_le32(MD_FEATURE_CLUSTERED);
2059
2060         if (rdev->badblocks.count == 0)
2061                 /* Nothing to do for bad blocks*/ ;
2062         else if (sb->bblog_offset == 0)
2063                 /* Cannot record bad blocks on this device */
2064                 md_error(mddev, rdev);
2065         else {
2066                 struct badblocks *bb = &rdev->badblocks;
2067                 __le64 *bbp = (__le64 *)page_address(rdev->bb_page);
2068                 u64 *p = bb->page;
2069                 sb->feature_map |= cpu_to_le32(MD_FEATURE_BAD_BLOCKS);
2070                 if (bb->changed) {
2071                         unsigned seq;
2072
2073 retry:
2074                         seq = read_seqbegin(&bb->lock);
2075
2076                         memset(bbp, 0xff, PAGE_SIZE);
2077
2078                         for (i = 0 ; i < bb->count ; i++) {
2079                                 u64 internal_bb = p[i];
2080                                 u64 store_bb = ((BB_OFFSET(internal_bb) << 10)
2081                                                 | BB_LEN(internal_bb));
2082                                 bbp[i] = cpu_to_le64(store_bb);
2083                         }
2084                         bb->changed = 0;
2085                         if (read_seqretry(&bb->lock, seq))
2086                                 goto retry;
2087
2088                         bb->sector = (rdev->sb_start +
2089                                       (int)le32_to_cpu(sb->bblog_offset));
2090                         bb->size = le16_to_cpu(sb->bblog_size);
2091                 }
2092         }
2093
2094         max_dev = 0;
2095         rdev_for_each(rdev2, mddev)
2096                 if (rdev2->desc_nr+1 > max_dev)
2097                         max_dev = rdev2->desc_nr+1;
2098
2099         if (max_dev > le32_to_cpu(sb->max_dev)) {
2100                 int bmask;
2101                 sb->max_dev = cpu_to_le32(max_dev);
2102                 rdev->sb_size = max_dev * 2 + 256;
2103                 bmask = queue_logical_block_size(rdev->bdev->bd_disk->queue)-1;
2104                 if (rdev->sb_size & bmask)
2105                         rdev->sb_size = (rdev->sb_size | bmask) + 1;
2106         } else
2107                 max_dev = le32_to_cpu(sb->max_dev);
2108
2109         for (i=0; i<max_dev;i++)
2110                 sb->dev_roles[i] = cpu_to_le16(MD_DISK_ROLE_SPARE);
2111
2112         if (test_bit(MD_HAS_JOURNAL, &mddev->flags))
2113                 sb->feature_map |= cpu_to_le32(MD_FEATURE_JOURNAL);
2114
2115         if (test_bit(MD_HAS_PPL, &mddev->flags)) {
2116                 if (test_bit(MD_HAS_MULTIPLE_PPLS, &mddev->flags))
2117                         sb->feature_map |=
2118                             cpu_to_le32(MD_FEATURE_MULTIPLE_PPLS);
2119                 else
2120                         sb->feature_map |= cpu_to_le32(MD_FEATURE_PPL);
2121                 sb->ppl.offset = cpu_to_le16(rdev->ppl.offset);
2122                 sb->ppl.size = cpu_to_le16(rdev->ppl.size);
2123         }
2124
2125         rdev_for_each(rdev2, mddev) {
2126                 i = rdev2->desc_nr;
2127                 if (test_bit(Faulty, &rdev2->flags))
2128                         sb->dev_roles[i] = cpu_to_le16(MD_DISK_ROLE_FAULTY);
2129                 else if (test_bit(In_sync, &rdev2->flags))
2130                         sb->dev_roles[i] = cpu_to_le16(rdev2->raid_disk);
2131                 else if (test_bit(Journal, &rdev2->flags))
2132                         sb->dev_roles[i] = cpu_to_le16(MD_DISK_ROLE_JOURNAL);
2133                 else if (rdev2->raid_disk >= 0)
2134                         sb->dev_roles[i] = cpu_to_le16(rdev2->raid_disk);
2135                 else
2136                         sb->dev_roles[i] = cpu_to_le16(MD_DISK_ROLE_SPARE);
2137         }
2138
2139         sb->sb_csum = calc_sb_1_csum(sb);
2140 }
2141
2142 static sector_t super_1_choose_bm_space(sector_t dev_size)
2143 {
2144         sector_t bm_space;
2145
2146         /* if the device is bigger than 8Gig, save 64k for bitmap
2147          * usage, if bigger than 200Gig, save 128k
2148          */
2149         if (dev_size < 64*2)
2150                 bm_space = 0;
2151         else if (dev_size - 64*2 >= 200*1024*1024*2)
2152                 bm_space = 128*2;
2153         else if (dev_size - 4*2 > 8*1024*1024*2)
2154                 bm_space = 64*2;
2155         else
2156                 bm_space = 4*2;
2157         return bm_space;
2158 }
2159
2160 static unsigned long long
2161 super_1_rdev_size_change(struct md_rdev *rdev, sector_t num_sectors)
2162 {
2163         struct mdp_superblock_1 *sb;
2164         sector_t max_sectors;
2165         if (num_sectors && num_sectors < rdev->mddev->dev_sectors)
2166                 return 0; /* component must fit device */
2167         if (rdev->data_offset != rdev->new_data_offset)
2168                 return 0; /* too confusing */
2169         if (rdev->sb_start < rdev->data_offset) {
2170                 /* minor versions 1 and 2; superblock before data */
2171                 max_sectors = i_size_read(rdev->bdev->bd_inode) >> 9;
2172                 max_sectors -= rdev->data_offset;
2173                 if (!num_sectors || num_sectors > max_sectors)
2174                         num_sectors = max_sectors;
2175         } else if (rdev->mddev->bitmap_info.offset) {
2176                 /* minor version 0 with bitmap we can't move */
2177                 return 0;
2178         } else {
2179                 /* minor version 0; superblock after data */
2180                 sector_t sb_start, bm_space;
2181                 sector_t dev_size = i_size_read(rdev->bdev->bd_inode) >> 9;
2182
2183                 /* 8K is for superblock */
2184                 sb_start = dev_size - 8*2;
2185                 sb_start &= ~(sector_t)(4*2 - 1);
2186
2187                 bm_space = super_1_choose_bm_space(dev_size);
2188
2189                 /* Space that can be used to store date needs to decrease
2190                  * superblock bitmap space and bad block space(4K)
2191                  */
2192                 max_sectors = sb_start - bm_space - 4*2;
2193
2194                 if (!num_sectors || num_sectors > max_sectors)
2195                         num_sectors = max_sectors;
2196         }
2197         sb = page_address(rdev->sb_page);
2198         sb->data_size = cpu_to_le64(num_sectors);
2199         sb->super_offset = cpu_to_le64(rdev->sb_start);
2200         sb->sb_csum = calc_sb_1_csum(sb);
2201         do {
2202                 md_super_write(rdev->mddev, rdev, rdev->sb_start, rdev->sb_size,
2203                                rdev->sb_page);
2204         } while (md_super_wait(rdev->mddev) < 0);
2205         return num_sectors;
2206
2207 }
2208
2209 static int
2210 super_1_allow_new_offset(struct md_rdev *rdev,
2211                          unsigned long long new_offset)
2212 {
2213         /* All necessary checks on new >= old have been done */
2214         struct bitmap *bitmap;
2215         if (new_offset >= rdev->data_offset)
2216                 return 1;
2217
2218         /* with 1.0 metadata, there is no metadata to tread on
2219          * so we can always move back */
2220         if (rdev->mddev->minor_version == 0)
2221                 return 1;
2222
2223         /* otherwise we must be sure not to step on
2224          * any metadata, so stay:
2225          * 36K beyond start of superblock
2226          * beyond end of badblocks
2227          * beyond write-intent bitmap
2228          */
2229         if (rdev->sb_start + (32+4)*2 > new_offset)
2230                 return 0;
2231         bitmap = rdev->mddev->bitmap;
2232         if (bitmap && !rdev->mddev->bitmap_info.file &&
2233             rdev->sb_start + rdev->mddev->bitmap_info.offset +
2234             bitmap->storage.file_pages * (PAGE_SIZE>>9) > new_offset)
2235                 return 0;
2236         if (rdev->badblocks.sector + rdev->badblocks.size > new_offset)
2237                 return 0;
2238
2239         return 1;
2240 }
2241
2242 static struct super_type super_types[] = {
2243         [0] = {
2244                 .name   = "0.90.0",
2245                 .owner  = THIS_MODULE,
2246                 .load_super         = super_90_load,
2247                 .validate_super     = super_90_validate,
2248                 .sync_super         = super_90_sync,
2249                 .rdev_size_change   = super_90_rdev_size_change,
2250                 .allow_new_offset   = super_90_allow_new_offset,
2251         },
2252         [1] = {
2253                 .name   = "md-1",
2254                 .owner  = THIS_MODULE,
2255                 .load_super         = super_1_load,
2256                 .validate_super     = super_1_validate,
2257                 .sync_super         = super_1_sync,
2258                 .rdev_size_change   = super_1_rdev_size_change,
2259                 .allow_new_offset   = super_1_allow_new_offset,
2260         },
2261 };
2262
2263 static void sync_super(struct mddev *mddev, struct md_rdev *rdev)
2264 {
2265         if (mddev->sync_super) {
2266                 mddev->sync_super(mddev, rdev);
2267                 return;
2268         }
2269
2270         BUG_ON(mddev->major_version >= ARRAY_SIZE(super_types));
2271
2272         super_types[mddev->major_version].sync_super(mddev, rdev);
2273 }
2274
2275 static int match_mddev_units(struct mddev *mddev1, struct mddev *mddev2)
2276 {
2277         struct md_rdev *rdev, *rdev2;
2278
2279         rcu_read_lock();
2280         rdev_for_each_rcu(rdev, mddev1) {
2281                 if (test_bit(Faulty, &rdev->flags) ||
2282                     test_bit(Journal, &rdev->flags) ||
2283                     rdev->raid_disk == -1)
2284                         continue;
2285                 rdev_for_each_rcu(rdev2, mddev2) {
2286                         if (test_bit(Faulty, &rdev2->flags) ||
2287                             test_bit(Journal, &rdev2->flags) ||
2288                             rdev2->raid_disk == -1)
2289                                 continue;
2290                         if (rdev->bdev->bd_disk == rdev2->bdev->bd_disk) {
2291                                 rcu_read_unlock();
2292                                 return 1;
2293                         }
2294                 }
2295         }
2296         rcu_read_unlock();
2297         return 0;
2298 }
2299
2300 static LIST_HEAD(pending_raid_disks);
2301
2302 /*
2303  * Try to register data integrity profile for an mddev
2304  *
2305  * This is called when an array is started and after a disk has been kicked
2306  * from the array. It only succeeds if all working and active component devices
2307  * are integrity capable with matching profiles.
2308  */
2309 int md_integrity_register(struct mddev *mddev)
2310 {
2311         struct md_rdev *rdev, *reference = NULL;
2312
2313         if (list_empty(&mddev->disks))
2314                 return 0; /* nothing to do */
2315         if (!mddev->gendisk || blk_get_integrity(mddev->gendisk))
2316                 return 0; /* shouldn't register, or already is */
2317         rdev_for_each(rdev, mddev) {
2318                 /* skip spares and non-functional disks */
2319                 if (test_bit(Faulty, &rdev->flags))
2320                         continue;
2321                 if (rdev->raid_disk < 0)
2322                         continue;
2323                 if (!reference) {
2324                         /* Use the first rdev as the reference */
2325                         reference = rdev;
2326                         continue;
2327                 }
2328                 /* does this rdev's profile match the reference profile? */
2329                 if (blk_integrity_compare(reference->bdev->bd_disk,
2330                                 rdev->bdev->bd_disk) < 0)
2331                         return -EINVAL;
2332         }
2333         if (!reference || !bdev_get_integrity(reference->bdev))
2334                 return 0;
2335         /*
2336          * All component devices are integrity capable and have matching
2337          * profiles, register the common profile for the md device.
2338          */
2339         blk_integrity_register(mddev->gendisk,
2340                                bdev_get_integrity(reference->bdev));
2341
2342         pr_debug("md: data integrity enabled on %s\n", mdname(mddev));
2343         if (bioset_integrity_create(&mddev->bio_set, BIO_POOL_SIZE) ||
2344             (mddev->level != 1 && mddev->level != 10 &&
2345              bioset_integrity_create(&mddev->io_acct_set, BIO_POOL_SIZE))) {
2346                 /*
2347                  * No need to handle the failure of bioset_integrity_create,
2348                  * because the function is called by md_run() -> pers->run(),
2349                  * md_run calls bioset_exit -> bioset_integrity_free in case
2350                  * of failure case.
2351                  */
2352                 pr_err("md: failed to create integrity pool for %s\n",
2353                        mdname(mddev));
2354                 return -EINVAL;
2355         }
2356         return 0;
2357 }
2358 EXPORT_SYMBOL(md_integrity_register);
2359
2360 /*
2361  * Attempt to add an rdev, but only if it is consistent with the current
2362  * integrity profile
2363  */
2364 int md_integrity_add_rdev(struct md_rdev *rdev, struct mddev *mddev)
2365 {
2366         struct blk_integrity *bi_mddev;
2367         char name[BDEVNAME_SIZE];
2368
2369         if (!mddev->gendisk)
2370                 return 0;
2371
2372         bi_mddev = blk_get_integrity(mddev->gendisk);
2373
2374         if (!bi_mddev) /* nothing to do */
2375                 return 0;
2376
2377         if (blk_integrity_compare(mddev->gendisk, rdev->bdev->bd_disk) != 0) {
2378                 pr_err("%s: incompatible integrity profile for %s\n",
2379                        mdname(mddev), bdevname(rdev->bdev, name));
2380                 return -ENXIO;
2381         }
2382
2383         return 0;
2384 }
2385 EXPORT_SYMBOL(md_integrity_add_rdev);
2386
2387 static bool rdev_read_only(struct md_rdev *rdev)
2388 {
2389         return bdev_read_only(rdev->bdev) ||
2390                 (rdev->meta_bdev && bdev_read_only(rdev->meta_bdev));
2391 }
2392
2393 static int bind_rdev_to_array(struct md_rdev *rdev, struct mddev *mddev)
2394 {
2395         char b[BDEVNAME_SIZE];
2396         int err;
2397
2398         /* prevent duplicates */
2399         if (find_rdev(mddev, rdev->bdev->bd_dev))
2400                 return -EEXIST;
2401
2402         if (rdev_read_only(rdev) && mddev->pers)
2403                 return -EROFS;
2404
2405         /* make sure rdev->sectors exceeds mddev->dev_sectors */
2406         if (!test_bit(Journal, &rdev->flags) &&
2407             rdev->sectors &&
2408             (mddev->dev_sectors == 0 || rdev->sectors < mddev->dev_sectors)) {
2409                 if (mddev->pers) {
2410                         /* Cannot change size, so fail
2411                          * If mddev->level <= 0, then we don't care
2412                          * about aligning sizes (e.g. linear)
2413                          */
2414                         if (mddev->level > 0)
2415                                 return -ENOSPC;
2416                 } else
2417                         mddev->dev_sectors = rdev->sectors;
2418         }
2419
2420         /* Verify rdev->desc_nr is unique.
2421          * If it is -1, assign a free number, else
2422          * check number is not in use
2423          */
2424         rcu_read_lock();
2425         if (rdev->desc_nr < 0) {
2426                 int choice = 0;
2427                 if (mddev->pers)
2428                         choice = mddev->raid_disks;
2429                 while (md_find_rdev_nr_rcu(mddev, choice))
2430                         choice++;
2431                 rdev->desc_nr = choice;
2432         } else {
2433                 if (md_find_rdev_nr_rcu(mddev, rdev->desc_nr)) {
2434                         rcu_read_unlock();
2435                         return -EBUSY;
2436                 }
2437         }
2438         rcu_read_unlock();
2439         if (!test_bit(Journal, &rdev->flags) &&
2440             mddev->max_disks && rdev->desc_nr >= mddev->max_disks) {
2441                 pr_warn("md: %s: array is limited to %d devices\n",
2442                         mdname(mddev), mddev->max_disks);
2443                 return -EBUSY;
2444         }
2445         bdevname(rdev->bdev,b);
2446         strreplace(b, '/', '!');
2447
2448         rdev->mddev = mddev;
2449         pr_debug("md: bind<%s>\n", b);
2450
2451         if (mddev->raid_disks)
2452                 mddev_create_serial_pool(mddev, rdev, false);
2453
2454         if ((err = kobject_add(&rdev->kobj, &mddev->kobj, "dev-%s", b)))
2455                 goto fail;
2456
2457         /* failure here is OK */
2458         err = sysfs_create_link(&rdev->kobj, bdev_kobj(rdev->bdev), "block");
2459         rdev->sysfs_state = sysfs_get_dirent_safe(rdev->kobj.sd, "state");
2460         rdev->sysfs_unack_badblocks =
2461                 sysfs_get_dirent_safe(rdev->kobj.sd, "unacknowledged_bad_blocks");
2462         rdev->sysfs_badblocks =
2463                 sysfs_get_dirent_safe(rdev->kobj.sd, "bad_blocks");
2464
2465         list_add_rcu(&rdev->same_set, &mddev->disks);
2466         bd_link_disk_holder(rdev->bdev, mddev->gendisk);
2467
2468         /* May as well allow recovery to be retried once */
2469         mddev->recovery_disabled++;
2470
2471         return 0;
2472
2473  fail:
2474         pr_warn("md: failed to register dev-%s for %s\n",
2475                 b, mdname(mddev));
2476         return err;
2477 }
2478
2479 static void rdev_delayed_delete(struct work_struct *ws)
2480 {
2481         struct md_rdev *rdev = container_of(ws, struct md_rdev, del_work);
2482         kobject_del(&rdev->kobj);
2483         kobject_put(&rdev->kobj);
2484 }
2485
2486 static void unbind_rdev_from_array(struct md_rdev *rdev)
2487 {
2488         char b[BDEVNAME_SIZE];
2489
2490         bd_unlink_disk_holder(rdev->bdev, rdev->mddev->gendisk);
2491         list_del_rcu(&rdev->same_set);
2492         pr_debug("md: unbind<%s>\n", bdevname(rdev->bdev,b));
2493         mddev_destroy_serial_pool(rdev->mddev, rdev, false);
2494         rdev->mddev = NULL;
2495         sysfs_remove_link(&rdev->kobj, "block");
2496         sysfs_put(rdev->sysfs_state);
2497         sysfs_put(rdev->sysfs_unack_badblocks);
2498         sysfs_put(rdev->sysfs_badblocks);
2499         rdev->sysfs_state = NULL;
2500         rdev->sysfs_unack_badblocks = NULL;
2501         rdev->sysfs_badblocks = NULL;
2502         rdev->badblocks.count = 0;
2503         /* We need to delay this, otherwise we can deadlock when
2504          * writing to 'remove' to "dev/state".  We also need
2505          * to delay it due to rcu usage.
2506          */
2507         synchronize_rcu();
2508         INIT_WORK(&rdev->del_work, rdev_delayed_delete);
2509         kobject_get(&rdev->kobj);
2510         queue_work(md_rdev_misc_wq, &rdev->del_work);
2511 }
2512
2513 /*
2514  * prevent the device from being mounted, repartitioned or
2515  * otherwise reused by a RAID array (or any other kernel
2516  * subsystem), by bd_claiming the device.
2517  */
2518 static int lock_rdev(struct md_rdev *rdev, dev_t dev, int shared)
2519 {
2520         int err = 0;
2521         struct block_device *bdev;
2522
2523         bdev = blkdev_get_by_dev(dev, FMODE_READ|FMODE_WRITE|FMODE_EXCL,
2524                                  shared ? (struct md_rdev *)lock_rdev : rdev);
2525         if (IS_ERR(bdev)) {
2526                 pr_warn("md: could not open device unknown-block(%u,%u).\n",
2527                         MAJOR(dev), MINOR(dev));
2528                 return PTR_ERR(bdev);
2529         }
2530         rdev->bdev = bdev;
2531         return err;
2532 }
2533
2534 static void unlock_rdev(struct md_rdev *rdev)
2535 {
2536         struct block_device *bdev = rdev->bdev;
2537         rdev->bdev = NULL;
2538         blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
2539 }
2540
2541 void md_autodetect_dev(dev_t dev);
2542
2543 static void export_rdev(struct md_rdev *rdev)
2544 {
2545         char b[BDEVNAME_SIZE];
2546
2547         pr_debug("md: export_rdev(%s)\n", bdevname(rdev->bdev,b));
2548         md_rdev_clear(rdev);
2549 #ifndef MODULE
2550         if (test_bit(AutoDetected, &rdev->flags))
2551                 md_autodetect_dev(rdev->bdev->bd_dev);
2552 #endif
2553         unlock_rdev(rdev);
2554         kobject_put(&rdev->kobj);
2555 }
2556
2557 void md_kick_rdev_from_array(struct md_rdev *rdev)
2558 {
2559         unbind_rdev_from_array(rdev);
2560         export_rdev(rdev);
2561 }
2562 EXPORT_SYMBOL_GPL(md_kick_rdev_from_array);
2563
2564 static void export_array(struct mddev *mddev)
2565 {
2566         struct md_rdev *rdev;
2567
2568         while (!list_empty(&mddev->disks)) {
2569                 rdev = list_first_entry(&mddev->disks, struct md_rdev,
2570                                         same_set);
2571                 md_kick_rdev_from_array(rdev);
2572         }
2573         mddev->raid_disks = 0;
2574         mddev->major_version = 0;
2575 }
2576
2577 static bool set_in_sync(struct mddev *mddev)
2578 {
2579         lockdep_assert_held(&mddev->lock);
2580         if (!mddev->in_sync) {
2581                 mddev->sync_checkers++;
2582                 spin_unlock(&mddev->lock);
2583                 percpu_ref_switch_to_atomic_sync(&mddev->writes_pending);
2584                 spin_lock(&mddev->lock);
2585                 if (!mddev->in_sync &&
2586                     percpu_ref_is_zero(&mddev->writes_pending)) {
2587                         mddev->in_sync = 1;
2588                         /*
2589                          * Ensure ->in_sync is visible before we clear
2590                          * ->sync_checkers.
2591                          */
2592                         smp_mb();
2593                         set_bit(MD_SB_CHANGE_CLEAN, &mddev->sb_flags);
2594                         sysfs_notify_dirent_safe(mddev->sysfs_state);
2595                 }
2596                 if (--mddev->sync_checkers == 0)
2597                         percpu_ref_switch_to_percpu(&mddev->writes_pending);
2598         }
2599         if (mddev->safemode == 1)
2600                 mddev->safemode = 0;
2601         return mddev->in_sync;
2602 }
2603
2604 static void sync_sbs(struct mddev *mddev, int nospares)
2605 {
2606         /* Update each superblock (in-memory image), but
2607          * if we are allowed to, skip spares which already
2608          * have the right event counter, or have one earlier
2609          * (which would mean they aren't being marked as dirty
2610          * with the rest of the array)
2611          */
2612         struct md_rdev *rdev;
2613         rdev_for_each(rdev, mddev) {
2614                 if (rdev->sb_events == mddev->events ||
2615                     (nospares &&
2616                      rdev->raid_disk < 0 &&
2617                      rdev->sb_events+1 == mddev->events)) {
2618                         /* Don't update this superblock */
2619                         rdev->sb_loaded = 2;
2620                 } else {
2621                         sync_super(mddev, rdev);
2622                         rdev->sb_loaded = 1;
2623                 }
2624         }
2625 }
2626
2627 static bool does_sb_need_changing(struct mddev *mddev)
2628 {
2629         struct md_rdev *rdev;
2630         struct mdp_superblock_1 *sb;
2631         int role;
2632
2633         /* Find a good rdev */
2634         rdev_for_each(rdev, mddev)
2635                 if ((rdev->raid_disk >= 0) && !test_bit(Faulty, &rdev->flags))
2636                         break;
2637
2638         /* No good device found. */
2639         if (!rdev)
2640                 return false;
2641
2642         sb = page_address(rdev->sb_page);
2643         /* Check if a device has become faulty or a spare become active */
2644         rdev_for_each(rdev, mddev) {
2645                 role = le16_to_cpu(sb->dev_roles[rdev->desc_nr]);
2646                 /* Device activated? */
2647                 if (role == 0xffff && rdev->raid_disk >=0 &&
2648                     !test_bit(Faulty, &rdev->flags))
2649                         return true;
2650                 /* Device turned faulty? */
2651                 if (test_bit(Faulty, &rdev->flags) && (role < 0xfffd))
2652                         return true;
2653         }
2654
2655         /* Check if any mddev parameters have changed */
2656         if ((mddev->dev_sectors != le64_to_cpu(sb->size)) ||
2657             (mddev->reshape_position != le64_to_cpu(sb->reshape_position)) ||
2658             (mddev->layout != le32_to_cpu(sb->layout)) ||
2659             (mddev->raid_disks != le32_to_cpu(sb->raid_disks)) ||
2660             (mddev->chunk_sectors != le32_to_cpu(sb->chunksize)))
2661                 return true;
2662
2663         return false;
2664 }
2665
2666 void md_update_sb(struct mddev *mddev, int force_change)
2667 {
2668         struct md_rdev *rdev;
2669         int sync_req;
2670         int nospares = 0;
2671         int any_badblocks_changed = 0;
2672         int ret = -1;
2673
2674         if (mddev->ro) {
2675                 if (force_change)
2676                         set_bit(MD_SB_CHANGE_DEVS, &mddev->sb_flags);
2677                 return;
2678         }
2679
2680 repeat:
2681         if (mddev_is_clustered(mddev)) {
2682                 if (test_and_clear_bit(MD_SB_CHANGE_DEVS, &mddev->sb_flags))
2683                         force_change = 1;
2684                 if (test_and_clear_bit(MD_SB_CHANGE_CLEAN, &mddev->sb_flags))
2685                         nospares = 1;
2686                 ret = md_cluster_ops->metadata_update_start(mddev);
2687                 /* Has someone else has updated the sb */
2688                 if (!does_sb_need_changing(mddev)) {
2689                         if (ret == 0)
2690                                 md_cluster_ops->metadata_update_cancel(mddev);
2691                         bit_clear_unless(&mddev->sb_flags, BIT(MD_SB_CHANGE_PENDING),
2692                                                          BIT(MD_SB_CHANGE_DEVS) |
2693                                                          BIT(MD_SB_CHANGE_CLEAN));
2694                         return;
2695                 }
2696         }
2697
2698         /*
2699          * First make sure individual recovery_offsets are correct
2700          * curr_resync_completed can only be used during recovery.
2701          * During reshape/resync it might use array-addresses rather
2702          * that device addresses.
2703          */
2704         rdev_for_each(rdev, mddev) {
2705                 if (rdev->raid_disk >= 0 &&
2706                     mddev->delta_disks >= 0 &&
2707                     test_bit(MD_RECOVERY_RUNNING, &mddev->recovery) &&
2708                     test_bit(MD_RECOVERY_RECOVER, &mddev->recovery) &&
2709                     !test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery) &&
2710                     !test_bit(Journal, &rdev->flags) &&
2711                     !test_bit(In_sync, &rdev->flags) &&
2712                     mddev->curr_resync_completed > rdev->recovery_offset)
2713                                 rdev->recovery_offset = mddev->curr_resync_completed;
2714
2715         }
2716         if (!mddev->persistent) {
2717                 clear_bit(MD_SB_CHANGE_CLEAN, &mddev->sb_flags);
2718                 clear_bit(MD_SB_CHANGE_DEVS, &mddev->sb_flags);
2719                 if (!mddev->external) {
2720                         clear_bit(MD_SB_CHANGE_PENDING, &mddev->sb_flags);
2721                         rdev_for_each(rdev, mddev) {
2722                                 if (rdev->badblocks.changed) {
2723                                         rdev->badblocks.changed = 0;
2724                                         ack_all_badblocks(&rdev->badblocks);
2725                                         md_error(mddev, rdev);
2726                                 }
2727                                 clear_bit(Blocked, &rdev->flags);
2728                                 clear_bit(BlockedBadBlocks, &rdev->flags);
2729                                 wake_up(&rdev->blocked_wait);
2730                         }
2731                 }
2732                 wake_up(&mddev->sb_wait);
2733                 return;
2734         }
2735
2736         spin_lock(&mddev->lock);
2737
2738         mddev->utime = ktime_get_real_seconds();
2739
2740         if (test_and_clear_bit(MD_SB_CHANGE_DEVS, &mddev->sb_flags))
2741                 force_change = 1;
2742         if (test_and_clear_bit(MD_SB_CHANGE_CLEAN, &mddev->sb_flags))
2743                 /* just a clean<-> dirty transition, possibly leave spares alone,
2744                  * though if events isn't the right even/odd, we will have to do
2745                  * spares after all
2746                  */
2747                 nospares = 1;
2748         if (force_change)
2749                 nospares = 0;
2750         if (mddev->degraded)
2751                 /* If the array is degraded, then skipping spares is both
2752                  * dangerous and fairly pointless.
2753                  * Dangerous because a device that was removed from the array
2754                  * might have a event_count that still looks up-to-date,
2755                  * so it can be re-added without a resync.
2756                  * Pointless because if there are any spares to skip,
2757                  * then a recovery will happen and soon that array won't
2758                  * be degraded any more and the spare can go back to sleep then.
2759                  */
2760                 nospares = 0;
2761
2762         sync_req = mddev->in_sync;
2763
2764         /* If this is just a dirty<->clean transition, and the array is clean
2765          * and 'events' is odd, we can roll back to the previous clean state */
2766         if (nospares
2767             && (mddev->in_sync && mddev->recovery_cp == MaxSector)
2768             && mddev->can_decrease_events
2769             && mddev->events != 1) {
2770                 mddev->events--;
2771                 mddev->can_decrease_events = 0;
2772         } else {
2773                 /* otherwise we have to go forward and ... */
2774                 mddev->events ++;
2775                 mddev->can_decrease_events = nospares;
2776         }
2777
2778         /*
2779          * This 64-bit counter should never wrap.
2780          * Either we are in around ~1 trillion A.C., assuming
2781          * 1 reboot per second, or we have a bug...
2782          */
2783         WARN_ON(mddev->events == 0);
2784
2785         rdev_for_each(rdev, mddev) {
2786                 if (rdev->badblocks.changed)
2787                         any_badblocks_changed++;
2788                 if (test_bit(Faulty, &rdev->flags))
2789                         set_bit(FaultRecorded, &rdev->flags);
2790         }
2791
2792         sync_sbs(mddev, nospares);
2793         spin_unlock(&mddev->lock);
2794
2795         pr_debug("md: updating %s RAID superblock on device (in sync %d)\n",
2796                  mdname(mddev), mddev->in_sync);
2797
2798         if (mddev->queue)
2799                 blk_add_trace_msg(mddev->queue, "md md_update_sb");
2800 rewrite:
2801         md_bitmap_update_sb(mddev->bitmap);
2802         rdev_for_each(rdev, mddev) {
2803                 char b[BDEVNAME_SIZE];
2804
2805                 if (rdev->sb_loaded != 1)
2806                         continue; /* no noise on spare devices */
2807
2808                 if (!test_bit(Faulty, &rdev->flags)) {
2809                         md_super_write(mddev,rdev,
2810                                        rdev->sb_start, rdev->sb_size,
2811                                        rdev->sb_page);
2812                         pr_debug("md: (write) %s's sb offset: %llu\n",
2813                                  bdevname(rdev->bdev, b),
2814                                  (unsigned long long)rdev->sb_start);
2815                         rdev->sb_events = mddev->events;
2816                         if (rdev->badblocks.size) {
2817                                 md_super_write(mddev, rdev,
2818                                                rdev->badblocks.sector,
2819                                                rdev->badblocks.size << 9,
2820                                                rdev->bb_page);
2821                                 rdev->badblocks.size = 0;
2822                         }
2823
2824                 } else
2825                         pr_debug("md: %s (skipping faulty)\n",
2826                                  bdevname(rdev->bdev, b));
2827
2828                 if (mddev->level == LEVEL_MULTIPATH)
2829                         /* only need to write one superblock... */
2830                         break;
2831         }
2832         if (md_super_wait(mddev) < 0)
2833                 goto rewrite;
2834         /* if there was a failure, MD_SB_CHANGE_DEVS was set, and we re-write super */
2835
2836         if (mddev_is_clustered(mddev) && ret == 0)
2837                 md_cluster_ops->metadata_update_finish(mddev);
2838
2839         if (mddev->in_sync != sync_req ||
2840             !bit_clear_unless(&mddev->sb_flags, BIT(MD_SB_CHANGE_PENDING),
2841                                BIT(MD_SB_CHANGE_DEVS) | BIT(MD_SB_CHANGE_CLEAN)))
2842                 /* have to write it out again */
2843                 goto repeat;
2844         wake_up(&mddev->sb_wait);
2845         if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery))
2846                 sysfs_notify_dirent_safe(mddev->sysfs_completed);
2847
2848         rdev_for_each(rdev, mddev) {
2849                 if (test_and_clear_bit(FaultRecorded, &rdev->flags))
2850                         clear_bit(Blocked, &rdev->flags);
2851
2852                 if (any_badblocks_changed)
2853                         ack_all_badblocks(&rdev->badblocks);
2854                 clear_bit(BlockedBadBlocks, &rdev->flags);
2855                 wake_up(&rdev->blocked_wait);
2856         }
2857 }
2858 EXPORT_SYMBOL(md_update_sb);
2859
2860 static int add_bound_rdev(struct md_rdev *rdev)
2861 {
2862         struct mddev *mddev = rdev->mddev;
2863         int err = 0;
2864         bool add_journal = test_bit(Journal, &rdev->flags);
2865
2866         if (!mddev->pers->hot_remove_disk || add_journal) {
2867                 /* If there is hot_add_disk but no hot_remove_disk
2868                  * then added disks for geometry changes,
2869                  * and should be added immediately.
2870                  */
2871                 super_types[mddev->major_version].
2872                         validate_super(mddev, rdev);
2873                 if (add_journal)
2874                         mddev_suspend(mddev);
2875                 err = mddev->pers->hot_add_disk(mddev, rdev);
2876                 if (add_journal)
2877                         mddev_resume(mddev);
2878                 if (err) {
2879                         md_kick_rdev_from_array(rdev);
2880                         return err;
2881                 }
2882         }
2883         sysfs_notify_dirent_safe(rdev->sysfs_state);
2884
2885         set_bit(MD_SB_CHANGE_DEVS, &mddev->sb_flags);
2886         if (mddev->degraded)
2887                 set_bit(MD_RECOVERY_RECOVER, &mddev->recovery);
2888         set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
2889         md_new_event(mddev);
2890         md_wakeup_thread(mddev->thread);
2891         return 0;
2892 }
2893
2894 /* words written to sysfs files may, or may not, be \n terminated.
2895  * We want to accept with case. For this we use cmd_match.
2896  */
2897 static int cmd_match(const char *cmd, const char *str)
2898 {
2899         /* See if cmd, written into a sysfs file, matches
2900          * str.  They must either be the same, or cmd can
2901          * have a trailing newline
2902          */
2903         while (*cmd && *str && *cmd == *str) {
2904                 cmd++;
2905                 str++;
2906         }
2907         if (*cmd == '\n')
2908                 cmd++;
2909         if (*str || *cmd)
2910                 return 0;
2911         return 1;
2912 }
2913
2914 struct rdev_sysfs_entry {
2915         struct attribute attr;
2916         ssize_t (*show)(struct md_rdev *, char *);
2917         ssize_t (*store)(struct md_rdev *, const char *, size_t);
2918 };
2919
2920 static ssize_t
2921 state_show(struct md_rdev *rdev, char *page)
2922 {
2923         char *sep = ",";
2924         size_t len = 0;
2925         unsigned long flags = READ_ONCE(rdev->flags);
2926
2927         if (test_bit(Faulty, &flags) ||
2928             (!test_bit(ExternalBbl, &flags) &&
2929             rdev->badblocks.unacked_exist))
2930                 len += sprintf(page+len, "faulty%s", sep);
2931         if (test_bit(In_sync, &flags))
2932                 len += sprintf(page+len, "in_sync%s", sep);
2933         if (test_bit(Journal, &flags))
2934                 len += sprintf(page+len, "journal%s", sep);
2935         if (test_bit(WriteMostly, &flags))
2936                 len += sprintf(page+len, "write_mostly%s", sep);
2937         if (test_bit(Blocked, &flags) ||
2938             (rdev->badblocks.unacked_exist
2939              && !test_bit(Faulty, &flags)))
2940                 len += sprintf(page+len, "blocked%s", sep);
2941         if (!test_bit(Faulty, &flags) &&
2942             !test_bit(Journal, &flags) &&
2943             !test_bit(In_sync, &flags))
2944                 len += sprintf(page+len, "spare%s", sep);
2945         if (test_bit(WriteErrorSeen, &flags))
2946                 len += sprintf(page+len, "write_error%s", sep);
2947         if (test_bit(WantReplacement, &flags))
2948                 len += sprintf(page+len, "want_replacement%s", sep);
2949         if (test_bit(Replacement, &flags))
2950                 len += sprintf(page+len, "replacement%s", sep);
2951         if (test_bit(ExternalBbl, &flags))
2952                 len += sprintf(page+len, "external_bbl%s", sep);
2953         if (test_bit(FailFast, &flags))
2954                 len += sprintf(page+len, "failfast%s", sep);
2955
2956         if (len)
2957                 len -= strlen(sep);
2958
2959         return len+sprintf(page+len, "\n");
2960 }
2961
2962 static ssize_t
2963 state_store(struct md_rdev *rdev, const char *buf, size_t len)
2964 {
2965         /* can write
2966          *  faulty  - simulates an error
2967          *  remove  - disconnects the device
2968          *  writemostly - sets write_mostly
2969          *  -writemostly - clears write_mostly
2970          *  blocked - sets the Blocked flags
2971          *  -blocked - clears the Blocked and possibly simulates an error
2972          *  insync - sets Insync providing device isn't active
2973          *  -insync - clear Insync for a device with a slot assigned,
2974          *            so that it gets rebuilt based on bitmap
2975          *  write_error - sets WriteErrorSeen
2976          *  -write_error - clears WriteErrorSeen
2977          *  {,-}failfast - set/clear FailFast
2978          */
2979         int err = -EINVAL;
2980         if (cmd_match(buf, "faulty") && rdev->mddev->pers) {
2981                 md_error(rdev->mddev, rdev);
2982                 if (test_bit(Faulty, &rdev->flags))
2983                         err = 0;
2984                 else
2985                         err = -EBUSY;
2986         } else if (cmd_match(buf, "remove")) {
2987                 if (rdev->mddev->pers) {
2988                         clear_bit(Blocked, &rdev->flags);
2989                         remove_and_add_spares(rdev->mddev, rdev);
2990                 }
2991                 if (rdev->raid_disk >= 0)
2992                         err = -EBUSY;
2993                 else {
2994                         struct mddev *mddev = rdev->mddev;
2995                         err = 0;
2996                         if (mddev_is_clustered(mddev))
2997                                 err = md_cluster_ops->remove_disk(mddev, rdev);
2998
2999                         if (err == 0) {
3000                                 md_kick_rdev_from_array(rdev);
3001                                 if (mddev->pers) {
3002                                         set_bit(MD_SB_CHANGE_DEVS, &mddev->sb_flags);
3003                                         md_wakeup_thread(mddev->thread);
3004                                 }
3005                                 md_new_event(mddev);
3006                         }
3007                 }
3008         } else if (cmd_match(buf, "writemostly")) {
3009                 set_bit(WriteMostly, &rdev->flags);
3010                 mddev_create_serial_pool(rdev->mddev, rdev, false);
3011                 err = 0;
3012         } else if (cmd_match(buf, "-writemostly")) {
3013                 mddev_destroy_serial_pool(rdev->mddev, rdev, false);
3014                 clear_bit(WriteMostly, &rdev->flags);
3015                 err = 0;
3016         } else if (cmd_match(buf, "blocked")) {
3017                 set_bit(Blocked, &rdev->flags);
3018                 err = 0;
3019         } else if (cmd_match(buf, "-blocked")) {
3020                 if (!test_bit(Faulty, &rdev->flags) &&
3021                     !test_bit(ExternalBbl, &rdev->flags) &&
3022                     rdev->badblocks.unacked_exist) {
3023                         /* metadata handler doesn't understand badblocks,
3024                          * so we need to fail the device
3025                          */
3026                         md_error(rdev->mddev, rdev);
3027                 }
3028                 clear_bit(Blocked, &rdev->flags);
3029                 clear_bit(BlockedBadBlocks, &rdev->flags);
3030                 wake_up(&rdev->blocked_wait);
3031                 set_bit(MD_RECOVERY_NEEDED, &rdev->mddev->recovery);
3032                 md_wakeup_thread(rdev->mddev->thread);
3033
3034                 err = 0;
3035         } else if (cmd_match(buf, "insync") && rdev->raid_disk == -1) {
3036                 set_bit(In_sync, &rdev->flags);
3037                 err = 0;
3038         } else if (cmd_match(buf, "failfast")) {
3039                 set_bit(FailFast, &rdev->flags);
3040                 err = 0;
3041         } else if (cmd_match(buf, "-failfast")) {
3042                 clear_bit(FailFast, &rdev->flags);
3043                 err = 0;
3044         } else if (cmd_match(buf, "-insync") && rdev->raid_disk >= 0 &&
3045                    !test_bit(Journal, &rdev->flags)) {
3046                 if (rdev->mddev->pers == NULL) {
3047                         clear_bit(In_sync, &rdev->flags);
3048                         rdev->saved_raid_disk = rdev->raid_disk;
3049                         rdev->raid_disk = -1;
3050                         err = 0;
3051                 }
3052         } else if (cmd_match(buf, "write_error")) {
3053                 set_bit(WriteErrorSeen, &rdev->flags);
3054                 err = 0;
3055         } else if (cmd_match(buf, "-write_error")) {
3056                 clear_bit(WriteErrorSeen, &rdev->flags);
3057                 err = 0;
3058         } else if (cmd_match(buf, "want_replacement")) {
3059                 /* Any non-spare device that is not a replacement can
3060                  * become want_replacement at any time, but we then need to
3061                  * check if recovery is needed.
3062                  */
3063                 if (rdev->raid_disk >= 0 &&
3064                     !test_bit(Journal, &rdev->flags) &&
3065                     !test_bit(Replacement, &rdev->flags))
3066                         set_bit(WantReplacement, &rdev->flags);
3067                 set_bit(MD_RECOVERY_NEEDED, &rdev->mddev->recovery);
3068                 md_wakeup_thread(rdev->mddev->thread);
3069                 err = 0;
3070         } else if (cmd_match(buf, "-want_replacement")) {
3071                 /* Clearing 'want_replacement' is always allowed.
3072                  * Once replacements starts it is too late though.
3073                  */
3074                 err = 0;
3075                 clear_bit(WantReplacement, &rdev->flags);
3076         } else if (cmd_match(buf, "replacement")) {
3077                 /* Can only set a device as a replacement when array has not
3078                  * yet been started.  Once running, replacement is automatic
3079                  * from spares, or by assigning 'slot'.
3080                  */
3081                 if (rdev->mddev->pers)
3082                         err = -EBUSY;
3083                 else {
3084                         set_bit(Replacement, &rdev->flags);
3085                         err = 0;
3086                 }
3087         } else if (cmd_match(buf, "-replacement")) {
3088                 /* Similarly, can only clear Replacement before start */
3089                 if (rdev->mddev->pers)
3090                         err = -EBUSY;
3091                 else {
3092                         clear_bit(Replacement, &rdev->flags);
3093                         err = 0;
3094                 }
3095         } else if (cmd_match(buf, "re-add")) {
3096                 if (!rdev->mddev->pers)
3097                         err = -EINVAL;
3098                 else if (test_bit(Faulty, &rdev->flags) && (rdev->raid_disk == -1) &&
3099                                 rdev->saved_raid_disk >= 0) {
3100                         /* clear_bit is performed _after_ all the devices
3101                          * have their local Faulty bit cleared. If any writes
3102                          * happen in the meantime in the local node, they
3103                          * will land in the local bitmap, which will be synced
3104                          * by this node eventually
3105                          */
3106                         if (!mddev_is_clustered(rdev->mddev) ||
3107                             (err = md_cluster_ops->gather_bitmaps(rdev)) == 0) {
3108                                 clear_bit(Faulty, &rdev->flags);
3109                                 err = add_bound_rdev(rdev);
3110                         }
3111                 } else
3112                         err = -EBUSY;
3113         } else if (cmd_match(buf, "external_bbl") && (rdev->mddev->external)) {
3114                 set_bit(ExternalBbl, &rdev->flags);
3115                 rdev->badblocks.shift = 0;
3116                 err = 0;
3117         } else if (cmd_match(buf, "-external_bbl") && (rdev->mddev->external)) {
3118                 clear_bit(ExternalBbl, &rdev->flags);
3119                 err = 0;
3120         }
3121         if (!err)
3122                 sysfs_notify_dirent_safe(rdev->sysfs_state);
3123         return err ? err : len;
3124 }
3125 static struct rdev_sysfs_entry rdev_state =
3126 __ATTR_PREALLOC(state, S_IRUGO|S_IWUSR, state_show, state_store);
3127
3128 static ssize_t
3129 errors_show(struct md_rdev *rdev, char *page)
3130 {
3131         return sprintf(page, "%d\n", atomic_read(&rdev->corrected_errors));
3132 }
3133
3134 static ssize_t
3135 errors_store(struct md_rdev *rdev, const char *buf, size_t len)
3136 {
3137         unsigned int n;
3138         int rv;
3139
3140         rv = kstrtouint(buf, 10, &n);
3141         if (rv < 0)
3142                 return rv;
3143         atomic_set(&rdev->corrected_errors, n);
3144         return len;
3145 }
3146 static struct rdev_sysfs_entry rdev_errors =
3147 __ATTR(errors, S_IRUGO|S_IWUSR, errors_show, errors_store);
3148
3149 static ssize_t
3150 slot_show(struct md_rdev *rdev, char *page)
3151 {
3152         if (test_bit(Journal, &rdev->flags))
3153                 return sprintf(page, "journal\n");
3154         else if (rdev->raid_disk < 0)
3155                 return sprintf(page, "none\n");
3156         else
3157                 return sprintf(page, "%d\n", rdev->raid_disk);
3158 }
3159
3160 static ssize_t
3161 slot_store(struct md_rdev *rdev, const char *buf, size_t len)
3162 {
3163         int slot;
3164         int err;
3165
3166         if (test_bit(Journal, &rdev->flags))
3167                 return -EBUSY;
3168         if (strncmp(buf, "none", 4)==0)
3169                 slot = -1;
3170         else {
3171                 err = kstrtouint(buf, 10, (unsigned int *)&slot);
3172                 if (err < 0)
3173                         return err;
3174         }
3175         if (rdev->mddev->pers && slot == -1) {
3176                 /* Setting 'slot' on an active array requires also
3177                  * updating the 'rd%d' link, and communicating
3178                  * with the personality with ->hot_*_disk.
3179                  * For now we only support removing
3180                  * failed/spare devices.  This normally happens automatically,
3181                  * but not when the metadata is externally managed.
3182                  */
3183                 if (rdev->raid_disk == -1)
3184                         return -EEXIST;
3185                 /* personality does all needed checks */
3186                 if (rdev->mddev->pers->hot_remove_disk == NULL)
3187                         return -EINVAL;
3188                 clear_bit(Blocked, &rdev->flags);
3189                 remove_and_add_spares(rdev->mddev, rdev);
3190                 if (rdev->raid_disk >= 0)
3191                         return -EBUSY;
3192                 set_bit(MD_RECOVERY_NEEDED, &rdev->mddev->recovery);
3193                 md_wakeup_thread(rdev->mddev->thread);
3194         } else if (rdev->mddev->pers) {
3195                 /* Activating a spare .. or possibly reactivating
3196                  * if we ever get bitmaps working here.
3197                  */
3198                 int err;
3199
3200                 if (rdev->raid_disk != -1)
3201                         return -EBUSY;
3202
3203                 if (test_bit(MD_RECOVERY_RUNNING, &rdev->mddev->recovery))
3204                         return -EBUSY;
3205
3206                 if (rdev->mddev->pers->hot_add_disk == NULL)
3207                         return -EINVAL;
3208
3209                 if (slot >= rdev->mddev->raid_disks &&
3210                     slot >= rdev->mddev->raid_disks + rdev->mddev->delta_disks)
3211                         return -ENOSPC;
3212
3213                 rdev->raid_disk = slot;
3214                 if (test_bit(In_sync, &rdev->flags))
3215                         rdev->saved_raid_disk = slot;
3216                 else
3217                         rdev->saved_raid_disk = -1;
3218                 clear_bit(In_sync, &rdev->flags);
3219                 clear_bit(Bitmap_sync, &rdev->flags);
3220                 err = rdev->mddev->pers->hot_add_disk(rdev->mddev, rdev);
3221                 if (err) {
3222                         rdev->raid_disk = -1;
3223                         return err;
3224                 } else
3225                         sysfs_notify_dirent_safe(rdev->sysfs_state);
3226                 /* failure here is OK */;
3227                 sysfs_link_rdev(rdev->mddev, rdev);
3228                 /* don't wakeup anyone, leave that to userspace. */
3229         } else {
3230                 if (slot >= rdev->mddev->raid_disks &&
3231                     slot >= rdev->mddev->raid_disks + rdev->mddev->delta_disks)
3232                         return -ENOSPC;
3233                 rdev->raid_disk = slot;
3234                 /* assume it is working */
3235                 clear_bit(Faulty, &rdev->flags);
3236                 clear_bit(WriteMostly, &rdev->flags);
3237                 set_bit(In_sync, &rdev->flags);
3238                 sysfs_notify_dirent_safe(rdev->sysfs_state);
3239         }
3240         return len;
3241 }
3242
3243 static struct rdev_sysfs_entry rdev_slot =
3244 __ATTR(slot, S_IRUGO|S_IWUSR, slot_show, slot_store);
3245
3246 static ssize_t
3247 offset_show(struct md_rdev *rdev, char *page)
3248 {
3249         return sprintf(page, "%llu\n", (unsigned long long)rdev->data_offset);
3250 }
3251
3252 static ssize_t
3253 offset_store(struct md_rdev *rdev, const char *buf, size_t len)
3254 {
3255         unsigned long long offset;
3256         if (kstrtoull(buf, 10, &offset) < 0)
3257                 return -EINVAL;
3258         if (rdev->mddev->pers && rdev->raid_disk >= 0)
3259                 return -EBUSY;
3260         if (rdev->sectors && rdev->mddev->external)
3261                 /* Must set offset before size, so overlap checks
3262                  * can be sane */
3263                 return -EBUSY;
3264         rdev->data_offset = offset;
3265         rdev->new_data_offset = offset;
3266         return len;
3267 }
3268
3269 static struct rdev_sysfs_entry rdev_offset =
3270 __ATTR(offset, S_IRUGO|S_IWUSR, offset_show, offset_store);
3271
3272 static ssize_t new_offset_show(struct md_rdev *rdev, char *page)
3273 {
3274         return sprintf(page, "%llu\n",
3275                        (unsigned long long)rdev->new_data_offset);
3276 }
3277
3278 static ssize_t new_offset_store(struct md_rdev *rdev,
3279                                 const char *buf, size_t len)
3280 {
3281         unsigned long long new_offset;
3282         struct mddev *mddev = rdev->mddev;
3283
3284         if (kstrtoull(buf, 10, &new_offset) < 0)
3285                 return -EINVAL;
3286
3287         if (mddev->sync_thread ||
3288             test_bit(MD_RECOVERY_RUNNING,&mddev->recovery))
3289                 return -EBUSY;
3290         if (new_offset == rdev->data_offset)
3291                 /* reset is always permitted */
3292                 ;
3293         else if (new_offset > rdev->data_offset) {
3294                 /* must not push array size beyond rdev_sectors */
3295                 if (new_offset - rdev->data_offset
3296                     + mddev->dev_sectors > rdev->sectors)
3297                                 return -E2BIG;
3298         }
3299         /* Metadata worries about other space details. */
3300
3301         /* decreasing the offset is inconsistent with a backwards
3302          * reshape.
3303          */
3304         if (new_offset < rdev->data_offset &&
3305             mddev->reshape_backwards)
3306                 return -EINVAL;
3307         /* Increasing offset is inconsistent with forwards
3308          * reshape.  reshape_direction should be set to
3309          * 'backwards' first.
3310          */
3311         if (new_offset > rdev->data_offset &&
3312             !mddev->reshape_backwards)
3313                 return -EINVAL;
3314
3315         if (mddev->pers && mddev->persistent &&
3316             !super_types[mddev->major_version]
3317             .allow_new_offset(rdev, new_offset))
3318                 return -E2BIG;
3319         rdev->new_data_offset = new_offset;
3320         if (new_offset > rdev->data_offset)
3321                 mddev->reshape_backwards = 1;
3322         else if (new_offset < rdev->data_offset)
3323                 mddev->reshape_backwards = 0;
3324
3325         return len;
3326 }
3327 static struct rdev_sysfs_entry rdev_new_offset =
3328 __ATTR(new_offset, S_IRUGO|S_IWUSR, new_offset_show, new_offset_store);
3329
3330 static ssize_t
3331 rdev_size_show(struct md_rdev *rdev, char *page)
3332 {
3333         return sprintf(page, "%llu\n", (unsigned long long)rdev->sectors / 2);
3334 }
3335
3336 static int overlaps(sector_t s1, sector_t l1, sector_t s2, sector_t l2)
3337 {
3338         /* check if two start/length pairs overlap */
3339         if (s1+l1 <= s2)
3340                 return 0;
3341         if (s2+l2 <= s1)
3342                 return 0;
3343         return 1;
3344 }
3345
3346 static int strict_blocks_to_sectors(const char *buf, sector_t *sectors)
3347 {
3348         unsigned long long blocks;
3349         sector_t new;
3350
3351         if (kstrtoull(buf, 10, &blocks) < 0)
3352                 return -EINVAL;
3353
3354         if (blocks & 1ULL << (8 * sizeof(blocks) - 1))
3355                 return -EINVAL; /* sector conversion overflow */
3356
3357         new = blocks * 2;
3358         if (new != blocks * 2)
3359                 return -EINVAL; /* unsigned long long to sector_t overflow */
3360
3361         *sectors = new;
3362         return 0;
3363 }
3364
3365 static ssize_t
3366 rdev_size_store(struct md_rdev *rdev, const char *buf, size_t len)
3367 {
3368         struct mddev *my_mddev = rdev->mddev;
3369         sector_t oldsectors = rdev->sectors;
3370         sector_t sectors;
3371
3372         if (test_bit(Journal, &rdev->flags))
3373                 return -EBUSY;
3374         if (strict_blocks_to_sectors(buf, &sectors) < 0)
3375                 return -EINVAL;
3376         if (rdev->data_offset != rdev->new_data_offset)
3377                 return -EINVAL; /* too confusing */
3378         if (my_mddev->pers && rdev->raid_disk >= 0) {
3379                 if (my_mddev->persistent) {
3380                         sectors = super_types[my_mddev->major_version].
3381                                 rdev_size_change(rdev, sectors);
3382                         if (!sectors)
3383                                 return -EBUSY;
3384                 } else if (!sectors)
3385                         sectors = (i_size_read(rdev->bdev->bd_inode) >> 9) -
3386                                 rdev->data_offset;
3387                 if (!my_mddev->pers->resize)
3388                         /* Cannot change size for RAID0 or Linear etc */
3389                         return -EINVAL;
3390         }
3391         if (sectors < my_mddev->dev_sectors)
3392                 return -EINVAL; /* component must fit device */
3393
3394         rdev->sectors = sectors;
3395         if (sectors > oldsectors && my_mddev->external) {
3396                 /* Need to check that all other rdevs with the same
3397                  * ->bdev do not overlap.  'rcu' is sufficient to walk
3398                  * the rdev lists safely.
3399                  * This check does not provide a hard guarantee, it
3400                  * just helps avoid dangerous mistakes.
3401                  */
3402                 struct mddev *mddev;
3403                 int overlap = 0;
3404                 struct list_head *tmp;
3405
3406                 rcu_read_lock();
3407                 for_each_mddev(mddev, tmp) {
3408                         struct md_rdev *rdev2;
3409
3410                         rdev_for_each(rdev2, mddev)
3411                                 if (rdev->bdev == rdev2->bdev &&
3412                                     rdev != rdev2 &&
3413                                     overlaps(rdev->data_offset, rdev->sectors,
3414                                              rdev2->data_offset,
3415                                              rdev2->sectors)) {
3416                                         overlap = 1;
3417                                         break;
3418                                 }
3419                         if (overlap) {
3420                                 mddev_put(mddev);
3421                                 break;
3422                         }
3423                 }
3424                 rcu_read_unlock();
3425                 if (overlap) {
3426                         /* Someone else could have slipped in a size
3427                          * change here, but doing so is just silly.
3428                          * We put oldsectors back because we *know* it is
3429                          * safe, and trust userspace not to race with
3430                          * itself
3431                          */
3432                         rdev->sectors = oldsectors;
3433                         return -EBUSY;
3434                 }
3435         }
3436         return len;
3437 }
3438
3439 static struct rdev_sysfs_entry rdev_size =
3440 __ATTR(size, S_IRUGO|S_IWUSR, rdev_size_show, rdev_size_store);
3441
3442 static ssize_t recovery_start_show(struct md_rdev *rdev, char *page)
3443 {
3444         unsigned long long recovery_start = rdev->recovery_offset;
3445
3446         if (test_bit(In_sync, &rdev->flags) ||
3447             recovery_start == MaxSector)
3448                 return sprintf(page, "none\n");
3449
3450         return sprintf(page, "%llu\n", recovery_start);
3451 }
3452
3453 static ssize_t recovery_start_store(struct md_rdev *rdev, const char *buf, size_t len)
3454 {
3455         unsigned long long recovery_start;
3456
3457         if (cmd_match(buf, "none"))
3458                 recovery_start = MaxSector;
3459         else if (kstrtoull(buf, 10, &recovery_start))
3460                 return -EINVAL;
3461
3462         if (rdev->mddev->pers &&
3463             rdev->raid_disk >= 0)
3464                 return -EBUSY;
3465
3466         rdev->recovery_offset = recovery_start;
3467         if (recovery_start == MaxSector)
3468                 set_bit(In_sync, &rdev->flags);
3469         else
3470                 clear_bit(In_sync, &rdev->flags);
3471         return len;
3472 }
3473
3474 static struct rdev_sysfs_entry rdev_recovery_start =
3475 __ATTR(recovery_start, S_IRUGO|S_IWUSR, recovery_start_show, recovery_start_store);
3476
3477 /* sysfs access to bad-blocks list.
3478  * We present two files.
3479  * 'bad-blocks' lists sector numbers and lengths of ranges that
3480  *    are recorded as bad.  The list is truncated to fit within
3481  *    the one-page limit of sysfs.
3482  *    Writing "sector length" to this file adds an acknowledged
3483  *    bad block list.
3484  * 'unacknowledged-bad-blocks' lists bad blocks that have not yet
3485  *    been acknowledged.  Writing to this file adds bad blocks
3486  *    without acknowledging them.  This is largely for testing.
3487  */
3488 static ssize_t bb_show(struct md_rdev *rdev, char *page)
3489 {
3490         return badblocks_show(&rdev->badblocks, page, 0);
3491 }
3492 static ssize_t bb_store(struct md_rdev *rdev, const char *page, size_t len)
3493 {
3494         int rv = badblocks_store(&rdev->badblocks, page, len, 0);
3495         /* Maybe that ack was all we needed */
3496         if (test_and_clear_bit(BlockedBadBlocks, &rdev->flags))
3497                 wake_up(&rdev->blocked_wait);
3498         return rv;
3499 }
3500 static struct rdev_sysfs_entry rdev_bad_blocks =
3501 __ATTR(bad_blocks, S_IRUGO|S_IWUSR, bb_show, bb_store);
3502
3503 static ssize_t ubb_show(struct md_rdev *rdev, char *page)
3504 {
3505         return badblocks_show(&rdev->badblocks, page, 1);
3506 }
3507 static ssize_t ubb_store(struct md_rdev *rdev, const char *page, size_t len)
3508 {
3509         return badblocks_store(&rdev->badblocks, page, len, 1);
3510 }
3511 static struct rdev_sysfs_entry rdev_unack_bad_blocks =
3512 __ATTR(unacknowledged_bad_blocks, S_IRUGO|S_IWUSR, ubb_show, ubb_store);
3513
3514 static ssize_t
3515 ppl_sector_show(struct md_rdev *rdev, char *page)
3516 {
3517         return sprintf(page, "%llu\n", (unsigned long long)rdev->ppl.sector);
3518 }
3519
3520 static ssize_t
3521 ppl_sector_store(struct md_rdev *rdev, const char *buf, size_t len)
3522 {
3523         unsigned long long sector;
3524
3525         if (kstrtoull(buf, 10, &sector) < 0)
3526                 return -EINVAL;
3527         if (sector != (sector_t)sector)
3528                 return -EINVAL;
3529
3530         if (rdev->mddev->pers && test_bit(MD_HAS_PPL, &rdev->mddev->flags) &&
3531             rdev->raid_disk >= 0)
3532                 return -EBUSY;
3533
3534         if (rdev->mddev->persistent) {
3535                 if (rdev->mddev->major_version == 0)
3536                         return -EINVAL;
3537                 if ((sector > rdev->sb_start &&
3538                      sector - rdev->sb_start > S16_MAX) ||
3539                     (sector < rdev->sb_start &&
3540                      rdev->sb_start - sector > -S16_MIN))
3541                         return -EINVAL;
3542                 rdev->ppl.offset = sector - rdev->sb_start;
3543         } else if (!rdev->mddev->external) {
3544                 return -EBUSY;
3545         }
3546         rdev->ppl.sector = sector;
3547         return len;
3548 }
3549
3550 static struct rdev_sysfs_entry rdev_ppl_sector =
3551 __ATTR(ppl_sector, S_IRUGO|S_IWUSR, ppl_sector_show, ppl_sector_store);
3552
3553 static ssize_t
3554 ppl_size_show(struct md_rdev *rdev, char *page)
3555 {
3556         return sprintf(page, "%u\n", rdev->ppl.size);
3557 }
3558
3559 static ssize_t
3560 ppl_size_store(struct md_rdev *rdev, const char *buf, size_t len)
3561 {
3562         unsigned int size;
3563
3564         if (kstrtouint(buf, 10, &size) < 0)
3565                 return -EINVAL;
3566
3567         if (rdev->mddev->pers && test_bit(MD_HAS_PPL, &rdev->mddev->flags) &&
3568             rdev->raid_disk >= 0)
3569                 return -EBUSY;
3570
3571         if (rdev->mddev->persistent) {
3572                 if (rdev->mddev->major_version == 0)
3573                         return -EINVAL;
3574                 if (size > U16_MAX)
3575                         return -EINVAL;
3576         } else if (!rdev->mddev->external) {
3577                 return -EBUSY;
3578         }
3579         rdev->ppl.size = size;
3580         return len;
3581 }
3582
3583 static struct rdev_sysfs_entry rdev_ppl_size =
3584 __ATTR(ppl_size, S_IRUGO|S_IWUSR, ppl_size_show, ppl_size_store);
3585
3586 static struct attribute *rdev_default_attrs[] = {
3587         &rdev_state.attr,
3588         &rdev_errors.attr,
3589         &rdev_slot.attr,
3590         &rdev_offset.attr,
3591         &rdev_new_offset.attr,
3592         &rdev_size.attr,
3593         &rdev_recovery_start.attr,
3594         &rdev_bad_blocks.attr,
3595         &rdev_unack_bad_blocks.attr,
3596         &rdev_ppl_sector.attr,
3597         &rdev_ppl_size.attr,
3598         NULL,
3599 };
3600 static ssize_t
3601 rdev_attr_show(struct kobject *kobj, struct attribute *attr, char *page)
3602 {
3603         struct rdev_sysfs_entry *entry = container_of(attr, struct rdev_sysfs_entry, attr);
3604         struct md_rdev *rdev = container_of(kobj, struct md_rdev, kobj);
3605
3606         if (!entry->show)
3607                 return -EIO;
3608         if (!rdev->mddev)
3609                 return -ENODEV;
3610         return entry->show(rdev, page);
3611 }
3612
3613 static ssize_t
3614 rdev_attr_store(struct kobject *kobj, struct attribute *attr,
3615               const char *page, size_t length)
3616 {
3617         struct rdev_sysfs_entry *entry = container_of(attr, struct rdev_sysfs_entry, attr);
3618         struct md_rdev *rdev = container_of(kobj, struct md_rdev, kobj);
3619         ssize_t rv;
3620         struct mddev *mddev = rdev->mddev;
3621
3622         if (!entry->store)
3623                 return -EIO;
3624         if (!capable(CAP_SYS_ADMIN))
3625                 return -EACCES;
3626         rv = mddev ? mddev_lock(mddev) : -ENODEV;
3627         if (!rv) {
3628                 if (rdev->mddev == NULL)
3629                         rv = -ENODEV;
3630                 else
3631                         rv = entry->store(rdev, page, length);
3632                 mddev_unlock(mddev);
3633         }
3634         return rv;
3635 }
3636
3637 static void rdev_free(struct kobject *ko)
3638 {
3639         struct md_rdev *rdev = container_of(ko, struct md_rdev, kobj);
3640         kfree(rdev);
3641 }
3642 static const struct sysfs_ops rdev_sysfs_ops = {
3643         .show           = rdev_attr_show,
3644         .store          = rdev_attr_store,
3645 };
3646 static struct kobj_type rdev_ktype = {
3647         .release        = rdev_free,
3648         .sysfs_ops      = &rdev_sysfs_ops,
3649         .default_attrs  = rdev_default_attrs,
3650 };
3651
3652 int md_rdev_init(struct md_rdev *rdev)
3653 {
3654         rdev->desc_nr = -1;
3655         rdev->saved_raid_disk = -1;
3656         rdev->raid_disk = -1;
3657         rdev->flags = 0;
3658         rdev->data_offset = 0;
3659         rdev->new_data_offset = 0;
3660         rdev->sb_events = 0;
3661         rdev->last_read_error = 0;
3662         rdev->sb_loaded = 0;
3663         rdev->bb_page = NULL;
3664         atomic_set(&rdev->nr_pending, 0);
3665         atomic_set(&rdev->read_errors, 0);
3666         atomic_set(&rdev->corrected_errors, 0);
3667
3668         INIT_LIST_HEAD(&rdev->same_set);
3669         init_waitqueue_head(&rdev->blocked_wait);
3670
3671         /* Add space to store bad block list.
3672          * This reserves the space even on arrays where it cannot
3673          * be used - I wonder if that matters
3674          */
3675         return badblocks_init(&rdev->badblocks, 0);
3676 }
3677 EXPORT_SYMBOL_GPL(md_rdev_init);
3678 /*
3679  * Import a device. If 'super_format' >= 0, then sanity check the superblock
3680  *
3681  * mark the device faulty if:
3682  *
3683  *   - the device is nonexistent (zero size)
3684  *   - the device has no valid superblock
3685  *
3686  * a faulty rdev _never_ has rdev->sb set.
3687  */
3688 static struct md_rdev *md_import_device(dev_t newdev, int super_format, int super_minor)
3689 {
3690         char b[BDEVNAME_SIZE];
3691         int err;
3692         struct md_rdev *rdev;
3693         sector_t size;
3694
3695         rdev = kzalloc(sizeof(*rdev), GFP_KERNEL);
3696         if (!rdev)
3697                 return ERR_PTR(-ENOMEM);
3698
3699         err = md_rdev_init(rdev);
3700         if (err)
3701                 goto abort_free;
3702         err = alloc_disk_sb(rdev);
3703         if (err)
3704                 goto abort_free;
3705
3706         err = lock_rdev(rdev, newdev, super_format == -2);
3707         if (err)
3708                 goto abort_free;
3709
3710         kobject_init(&rdev->kobj, &rdev_ktype);
3711
3712         size = i_size_read(rdev->bdev->bd_inode) >> BLOCK_SIZE_BITS;
3713         if (!size) {
3714                 pr_warn("md: %s has zero or unknown size, marking faulty!\n",
3715                         bdevname(rdev->bdev,b));
3716                 err = -EINVAL;
3717                 goto abort_free;
3718         }
3719
3720         if (super_format >= 0) {
3721                 err = super_types[super_format].
3722                         load_super(rdev, NULL, super_minor);
3723                 if (err == -EINVAL) {
3724                         pr_warn("md: %s does not have a valid v%d.%d superblock, not importing!\n",
3725                                 bdevname(rdev->bdev,b),
3726                                 super_format, super_minor);
3727                         goto abort_free;
3728                 }
3729                 if (err < 0) {
3730                         pr_warn("md: could not read %s's sb, not importing!\n",
3731                                 bdevname(rdev->bdev,b));
3732                         goto abort_free;
3733                 }
3734         }
3735
3736         return rdev;
3737
3738 abort_free:
3739         if (rdev->bdev)
3740                 unlock_rdev(rdev);
3741         md_rdev_clear(rdev);
3742         kfree(rdev);
3743         return ERR_PTR(err);
3744 }
3745
3746 /*
3747  * Check a full RAID array for plausibility
3748  */
3749
3750 static int analyze_sbs(struct mddev *mddev)
3751 {
3752         int i;
3753         struct md_rdev *rdev, *freshest, *tmp;
3754         char b[BDEVNAME_SIZE];
3755
3756         freshest = NULL;
3757         rdev_for_each_safe(rdev, tmp, mddev)
3758                 switch (super_types[mddev->major_version].
3759                         load_super(rdev, freshest, mddev->minor_version)) {
3760                 case 1:
3761                         freshest = rdev;
3762                         break;
3763                 case 0:
3764                         break;
3765                 default:
3766                         pr_warn("md: fatal superblock inconsistency in %s -- removing from array\n",
3767                                 bdevname(rdev->bdev,b));
3768                         md_kick_rdev_from_array(rdev);
3769                 }
3770
3771         /* Cannot find a valid fresh disk */
3772         if (!freshest) {
3773                 pr_warn("md: cannot find a valid disk\n");
3774                 return -EINVAL;
3775         }
3776
3777         super_types[mddev->major_version].
3778                 validate_super(mddev, freshest);
3779
3780         i = 0;
3781         rdev_for_each_safe(rdev, tmp, mddev) {
3782                 if (mddev->max_disks &&
3783                     (rdev->desc_nr >= mddev->max_disks ||
3784                      i > mddev->max_disks)) {
3785                         pr_warn("md: %s: %s: only %d devices permitted\n",
3786                                 mdname(mddev), bdevname(rdev->bdev, b),
3787                                 mddev->max_disks);
3788                         md_kick_rdev_from_array(rdev);
3789                         continue;
3790                 }
3791                 if (rdev != freshest) {
3792                         if (super_types[mddev->major_version].
3793                             validate_super(mddev, rdev)) {
3794                                 pr_warn("md: kicking non-fresh %s from array!\n",
3795                                         bdevname(rdev->bdev,b));
3796                                 md_kick_rdev_from_array(rdev);
3797                                 continue;
3798                         }
3799                 }
3800                 if (mddev->level == LEVEL_MULTIPATH) {
3801                         rdev->desc_nr = i++;
3802                         rdev->raid_disk = rdev->desc_nr;
3803                         set_bit(In_sync, &rdev->flags);
3804                 } else if (rdev->raid_disk >=
3805                             (mddev->raid_disks - min(0, mddev->delta_disks)) &&
3806                            !test_bit(Journal, &rdev->flags)) {
3807                         rdev->raid_disk = -1;
3808                         clear_bit(In_sync, &rdev->flags);
3809                 }
3810         }
3811
3812         return 0;
3813 }
3814
3815 /* Read a fixed-point number.
3816  * Numbers in sysfs attributes should be in "standard" units where
3817  * possible, so time should be in seconds.
3818  * However we internally use a a much smaller unit such as
3819  * milliseconds or jiffies.
3820  * This function takes a decimal number with a possible fractional
3821  * component, and produces an integer which is the result of
3822  * multiplying that number by 10^'scale'.
3823  * all without any floating-point arithmetic.
3824  */
3825 int strict_strtoul_scaled(const char *cp, unsigned long *res, int scale)
3826 {
3827         unsigned long result = 0;
3828         long decimals = -1;
3829         while (isdigit(*cp) || (*cp == '.' && decimals < 0)) {
3830                 if (*cp == '.')
3831                         decimals = 0;
3832                 else if (decimals < scale) {
3833                         unsigned int value;
3834                         value = *cp - '0';
3835                         result = result * 10 + value;
3836                         if (decimals >= 0)
3837                                 decimals++;
3838                 }
3839                 cp++;
3840         }
3841         if (*cp == '\n')
3842                 cp++;
3843         if (*cp)
3844                 return -EINVAL;
3845         if (decimals < 0)
3846                 decimals = 0;
3847         *res = result * int_pow(10, scale - decimals);
3848         return 0;
3849 }
3850
3851 static ssize_t
3852 safe_delay_show(struct mddev *mddev, char *page)
3853 {
3854         int msec = (mddev->safemode_delay*1000)/HZ;
3855         return sprintf(page, "%d.%03d\n", msec/1000, msec%1000);
3856 }
3857 static ssize_t
3858 safe_delay_store(struct mddev *mddev, const char *cbuf, size_t len)
3859 {
3860         unsigned long msec;
3861
3862         if (mddev_is_clustered(mddev)) {
3863                 pr_warn("md: Safemode is disabled for clustered mode\n");
3864                 return -EINVAL;
3865         }
3866
3867         if (strict_strtoul_scaled(cbuf, &msec, 3) < 0)
3868                 return -EINVAL;
3869         if (msec == 0)
3870                 mddev->safemode_delay = 0;
3871         else {
3872                 unsigned long old_delay = mddev->safemode_delay;
3873                 unsigned long new_delay = (msec*HZ)/1000;
3874
3875                 if (new_delay == 0)
3876                         new_delay = 1;
3877                 mddev->safemode_delay = new_delay;
3878                 if (new_delay < old_delay || old_delay == 0)
3879                         mod_timer(&mddev->safemode_timer, jiffies+1);
3880         }
3881         return len;
3882 }
3883 static struct md_sysfs_entry md_safe_delay =
3884 __ATTR(safe_mode_delay, S_IRUGO|S_IWUSR,safe_delay_show, safe_delay_store);
3885
3886 static ssize_t
3887 level_show(struct mddev *mddev, char *page)
3888 {
3889         struct md_personality *p;
3890         int ret;
3891         spin_lock(&mddev->lock);
3892         p = mddev->pers;
3893         if (p)
3894                 ret = sprintf(page, "%s\n", p->name);
3895         else if (mddev->clevel[0])
3896                 ret = sprintf(page, "%s\n", mddev->clevel);
3897         else if (mddev->level != LEVEL_NONE)
3898                 ret = sprintf(page, "%d\n", mddev->level);
3899         else
3900                 ret = 0;
3901         spin_unlock(&mddev->lock);
3902         return ret;
3903 }
3904
3905 static ssize_t
3906 level_store(struct mddev *mddev, const char *buf, size_t len)
3907 {
3908         char clevel[16];
3909         ssize_t rv;
3910         size_t slen = len;
3911         struct md_personality *pers, *oldpers;
3912         long level;
3913         void *priv, *oldpriv;
3914         struct md_rdev *rdev;
3915
3916         if (slen == 0 || slen >= sizeof(clevel))
3917                 return -EINVAL;
3918
3919         rv = mddev_lock(mddev);
3920         if (rv)
3921                 return rv;
3922
3923         if (mddev->pers == NULL) {
3924                 strncpy(mddev->clevel, buf, slen);
3925                 if (mddev->clevel[slen-1] == '\n')
3926                         slen--;
3927                 mddev->clevel[slen] = 0;
3928                 mddev->level = LEVEL_NONE;
3929                 rv = len;
3930                 goto out_unlock;
3931         }
3932         rv = -EROFS;
3933         if (mddev->ro)
3934                 goto out_unlock;
3935
3936         /* request to change the personality.  Need to ensure:
3937          *  - array is not engaged in resync/recovery/reshape
3938          *  - old personality can be suspended
3939          *  - new personality will access other array.
3940          */
3941
3942         rv = -EBUSY;
3943         if (mddev->sync_thread ||
3944             test_bit(MD_RECOVERY_RUNNING, &mddev->recovery) ||
3945             mddev->reshape_position != MaxSector ||
3946             mddev->sysfs_active)
3947                 goto out_unlock;
3948
3949         rv = -EINVAL;
3950         if (!mddev->pers->quiesce) {
3951                 pr_warn("md: %s: %s does not support online personality change\n",
3952                         mdname(mddev), mddev->pers->name);
3953                 goto out_unlock;
3954         }
3955
3956         /* Now find the new personality */
3957         strncpy(clevel, buf, slen);
3958         if (clevel[slen-1] == '\n')
3959                 slen--;
3960         clevel[slen] = 0;
3961         if (kstrtol(clevel, 10, &level))
3962                 level = LEVEL_NONE;
3963
3964         if (request_module("md-%s", clevel) != 0)
3965                 request_module("md-level-%s", clevel);
3966         spin_lock(&pers_lock);
3967         pers = find_pers(level, clevel);
3968         if (!pers || !try_module_get(pers->owner)) {
3969                 spin_unlock(&pers_lock);
3970                 pr_warn("md: personality %s not loaded\n", clevel);
3971                 rv = -EINVAL;
3972                 goto out_unlock;
3973         }
3974         spin_unlock(&pers_lock);
3975
3976         if (pers == mddev->pers) {
3977                 /* Nothing to do! */
3978                 module_put(pers->owner);
3979                 rv = len;
3980                 goto out_unlock;
3981         }
3982         if (!pers->takeover) {
3983                 module_put(pers->owner);
3984                 pr_warn("md: %s: %s does not support personality takeover\n",
3985                         mdname(mddev), clevel);
3986                 rv = -EINVAL;
3987                 goto out_unlock;
3988         }
3989
3990         rdev_for_each(rdev, mddev)
3991                 rdev->new_raid_disk = rdev->raid_disk;
3992
3993         /* ->takeover must set new_* and/or delta_disks
3994          * if it succeeds, and may set them when it fails.
3995          */
3996         priv = pers->takeover(mddev);
3997         if (IS_ERR(priv)) {
3998                 mddev->new_level = mddev->level;
3999                 mddev->new_layout = mddev->layout;
4000                 mddev->new_chunk_sectors = mddev->chunk_sectors;
4001                 mddev->raid_disks -= mddev->delta_disks;
4002                 mddev->delta_disks = 0;
4003                 mddev->reshape_backwards = 0;
4004                 module_put(pers->owner);
4005                 pr_warn("md: %s: %s would not accept array\n",
4006                         mdname(mddev), clevel);
4007                 rv = PTR_ERR(priv);
4008                 goto out_unlock;
4009         }
4010
4011         /* Looks like we have a winner */
4012         mddev_suspend(mddev);
4013         mddev_detach(mddev);
4014
4015         spin_lock(&mddev->lock);
4016         oldpers = mddev->pers;
4017         oldpriv = mddev->private;
4018         mddev->pers = pers;
4019         mddev->private = priv;
4020         strlcpy(mddev->clevel, pers->name, sizeof(mddev->clevel));
4021         mddev->level = mddev->new_level;
4022         mddev->layout = mddev->new_layout;
4023         mddev->chunk_sectors = mddev->new_chunk_sectors;
4024         mddev->delta_disks = 0;
4025         mddev->reshape_backwards = 0;
4026         mddev->degraded = 0;
4027         spin_unlock(&mddev->lock);
4028
4029         if (oldpers->sync_request == NULL &&
4030             mddev->external) {
4031                 /* We are converting from a no-redundancy array
4032                  * to a redundancy array and metadata is managed
4033                  * externally so we need to be sure that writes
4034                  * won't block due to a need to transition
4035                  *      clean->dirty
4036                  * until external management is started.
4037                  */
4038                 mddev->in_sync = 0;
4039                 mddev->safemode_delay = 0;
4040                 mddev->safemode = 0;
4041         }
4042
4043         oldpers->free(mddev, oldpriv);
4044
4045         if (oldpers->sync_request == NULL &&
4046             pers->sync_request != NULL) {
4047                 /* need to add the md_redundancy_group */
4048                 if (sysfs_create_group(&mddev->kobj, &md_redundancy_group))
4049                         pr_warn("md: cannot register extra attributes for %s\n",
4050                                 mdname(mddev));
4051                 mddev->sysfs_action = sysfs_get_dirent(mddev->kobj.sd, "sync_action");
4052                 mddev->sysfs_completed = sysfs_get_dirent_safe(mddev->kobj.sd, "sync_completed");
4053                 mddev->sysfs_degraded = sysfs_get_dirent_safe(mddev->kobj.sd, "degraded");
4054         }
4055         if (oldpers->sync_request != NULL &&
4056             pers->sync_request == NULL) {
4057                 /* need to remove the md_redundancy_group */
4058                 if (mddev->to_remove == NULL)
4059                         mddev->to_remove = &md_redundancy_group;
4060         }
4061
4062         module_put(oldpers->owner);
4063
4064         rdev_for_each(rdev, mddev) {
4065                 if (rdev->raid_disk < 0)
4066                         continue;
4067                 if (rdev->new_raid_disk >= mddev->raid_disks)
4068                         rdev->new_raid_disk = -1;
4069                 if (rdev->new_raid_disk == rdev->raid_disk)
4070                         continue;
4071                 sysfs_unlink_rdev(mddev, rdev);
4072         }
4073         rdev_for_each(rdev, mddev) {
4074                 if (rdev->raid_disk < 0)
4075                         continue;
4076                 if (rdev->new_raid_disk == rdev->raid_disk)
4077                         continue;
4078                 rdev->raid_disk = rdev->new_raid_disk;
4079                 if (rdev->raid_disk < 0)
4080                         clear_bit(In_sync, &rdev->flags);
4081                 else {
4082                         if (sysfs_link_rdev(mddev, rdev))
4083                                 pr_warn("md: cannot register rd%d for %s after level change\n",
4084                                         rdev->raid_disk, mdname(mddev));
4085                 }
4086         }
4087
4088         if (pers->sync_request == NULL) {
4089                 /* this is now an array without redundancy, so
4090                  * it must always be in_sync
4091                  */
4092                 mddev->in_sync = 1;
4093                 del_timer_sync(&mddev->safemode_timer);
4094         }
4095         blk_set_stacking_limits(&mddev->queue->limits);
4096         pers->run(mddev);
4097         set_bit(MD_SB_CHANGE_DEVS, &mddev->sb_flags);
4098         mddev_resume(mddev);
4099         if (!mddev->thread)
4100                 md_update_sb(mddev, 1);
4101         sysfs_notify_dirent_safe(mddev->sysfs_level);
4102         md_new_event(mddev);
4103         rv = len;
4104 out_unlock:
4105         mddev_unlock(mddev);
4106         return rv;
4107 }
4108
4109 static struct md_sysfs_entry md_level =
4110 __ATTR(level, S_IRUGO|S_IWUSR, level_show, level_store);
4111
4112 static ssize_t
4113 layout_show(struct mddev *mddev, char *page)
4114 {
4115         /* just a number, not meaningful for all levels */
4116         if (mddev->reshape_position != MaxSector &&
4117             mddev->layout != mddev->new_layout)
4118                 return sprintf(page, "%d (%d)\n",
4119                                mddev->new_layout, mddev->layout);
4120         return sprintf(page, "%d\n", mddev->layout);
4121 }
4122
4123 static ssize_t
4124 layout_store(struct mddev *mddev, const char *buf, size_t len)
4125 {
4126         unsigned int n;
4127         int err;
4128
4129         err = kstrtouint(buf, 10, &n);
4130         if (err < 0)
4131                 return err;
4132         err = mddev_lock(mddev);
4133         if (err)
4134                 return err;
4135
4136         if (mddev->pers) {
4137                 if (mddev->pers->check_reshape == NULL)
4138                         err = -EBUSY;
4139                 else if (mddev->ro)
4140                         err = -EROFS;
4141                 else {
4142                         mddev->new_layout = n;
4143                         err = mddev->pers->check_reshape(mddev);
4144                         if (err)
4145                                 mddev->new_layout = mddev->layout;
4146                 }
4147         } else {
4148                 mddev->new_layout = n;
4149                 if (mddev->reshape_position == MaxSector)
4150                         mddev->layout = n;
4151         }
4152         mddev_unlock(mddev);
4153         return err ?: len;
4154 }
4155 static struct md_sysfs_entry md_layout =
4156 __ATTR(layout, S_IRUGO|S_IWUSR, layout_show, layout_store);
4157
4158 static ssize_t
4159 raid_disks_show(struct mddev *mddev, char *page)
4160 {
4161         if (mddev->raid_disks == 0)
4162                 return 0;
4163         if (mddev->reshape_position != MaxSector &&
4164             mddev->delta_disks != 0)
4165                 return sprintf(page, "%d (%d)\n", mddev->raid_disks,
4166                                mddev->raid_disks - mddev->delta_disks);
4167         return sprintf(page, "%d\n", mddev->raid_disks);
4168 }
4169
4170 static int update_raid_disks(struct mddev *mddev, int raid_disks);
4171
4172 static ssize_t
4173 raid_disks_store(struct mddev *mddev, const char *buf, size_t len)
4174 {
4175         unsigned int n;
4176         int err;
4177
4178         err = kstrtouint(buf, 10, &n);
4179         if (err < 0)
4180                 return err;
4181
4182         err = mddev_lock(mddev);
4183         if (err)
4184                 return err;
4185         if (mddev->pers)
4186                 err = update_raid_disks(mddev, n);
4187         else if (mddev->reshape_position != MaxSector) {
4188                 struct md_rdev *rdev;
4189                 int olddisks = mddev->raid_disks - mddev->delta_disks;
4190
4191                 err = -EINVAL;
4192                 rdev_for_each(rdev, mddev) {
4193                         if (olddisks < n &&
4194                             rdev->data_offset < rdev->new_data_offset)
4195                                 goto out_unlock;
4196                         if (olddisks > n &&
4197                             rdev->data_offset > rdev->new_data_offset)
4198                                 goto out_unlock;
4199                 }
4200                 err = 0;
4201                 mddev->delta_disks = n - olddisks;
4202                 mddev->raid_disks = n;
4203                 mddev->reshape_backwards = (mddev->delta_disks < 0);
4204         } else
4205                 mddev->raid_disks = n;
4206 out_unlock:
4207         mddev_unlock(mddev);
4208         return err ? err : len;
4209 }
4210 static struct md_sysfs_entry md_raid_disks =
4211 __ATTR(raid_disks, S_IRUGO|S_IWUSR, raid_disks_show, raid_disks_store);
4212
4213 static ssize_t
4214 uuid_show(struct mddev *mddev, char *page)
4215 {
4216         return sprintf(page, "%pU\n", mddev->uuid);
4217 }
4218 static struct md_sysfs_entry md_uuid =
4219 __ATTR(uuid, S_IRUGO, uuid_show, NULL);
4220
4221 static ssize_t
4222 chunk_size_show(struct mddev *mddev, char *page)
4223 {
4224         if (mddev->reshape_position != MaxSector &&
4225             mddev->chunk_sectors != mddev->new_chunk_sectors)
4226                 return sprintf(page, "%d (%d)\n",
4227                                mddev->new_chunk_sectors << 9,
4228                                mddev->chunk_sectors << 9);
4229         return sprintf(page, "%d\n", mddev->chunk_sectors << 9);
4230 }
4231
4232 static ssize_t
4233 chunk_size_store(struct mddev *mddev, const char *buf, size_t len)
4234 {
4235         unsigned long n;
4236         int err;
4237
4238         err = kstrtoul(buf, 10, &n);
4239         if (err < 0)
4240                 return err;
4241
4242         err = mddev_lock(mddev);
4243         if (err)
4244                 return err;
4245         if (mddev->pers) {
4246                 if (mddev->pers->check_reshape == NULL)
4247                         err = -EBUSY;
4248                 else if (mddev->ro)
4249                         err = -EROFS;
4250                 else {
4251                         mddev->new_chunk_sectors = n >> 9;
4252                         err = mddev->pers->check_reshape(mddev);
4253                         if (err)
4254                                 mddev->new_chunk_sectors = mddev->chunk_sectors;
4255                 }
4256         } else {
4257                 mddev->new_chunk_sectors = n >> 9;
4258                 if (mddev->reshape_position == MaxSector)
4259                         mddev->chunk_sectors = n >> 9;
4260         }
4261         mddev_unlock(mddev);
4262         return err ?: len;
4263 }
4264 static struct md_sysfs_entry md_chunk_size =
4265 __ATTR(chunk_size, S_IRUGO|S_IWUSR, chunk_size_show, chunk_size_store);
4266
4267 static ssize_t
4268 resync_start_show(struct mddev *mddev, char *page)
4269 {
4270         if (mddev->recovery_cp == MaxSector)
4271                 return sprintf(page, "none\n");
4272         return sprintf(page, "%llu\n", (unsigned long long)mddev->recovery_cp);
4273 }
4274
4275 static ssize_t
4276 resync_start_store(struct mddev *mddev, const char *buf, size_t len)
4277 {
4278         unsigned long long n;
4279         int err;
4280
4281         if (cmd_match(buf, "none"))
4282                 n = MaxSector;
4283         else {
4284                 err = kstrtoull(buf, 10, &n);
4285                 if (err < 0)
4286                         return err;
4287                 if (n != (sector_t)n)
4288                         return -EINVAL;
4289         }
4290
4291         err = mddev_lock(mddev);
4292         if (err)
4293                 return err;
4294         if (mddev->pers && !test_bit(MD_RECOVERY_FROZEN, &mddev->recovery))
4295                 err = -EBUSY;
4296
4297         if (!err) {
4298                 mddev->recovery_cp = n;
4299                 if (mddev->pers)
4300                         set_bit(MD_SB_CHANGE_CLEAN, &mddev->sb_flags);
4301         }
4302         mddev_unlock(mddev);
4303         return err ?: len;
4304 }
4305 static struct md_sysfs_entry md_resync_start =
4306 __ATTR_PREALLOC(resync_start, S_IRUGO|S_IWUSR,
4307                 resync_start_show, resync_start_store);
4308
4309 /*
4310  * The array state can be:
4311  *
4312  * clear
4313  *     No devices, no size, no level
4314  *     Equivalent to STOP_ARRAY ioctl
4315  * inactive
4316  *     May have some settings, but array is not active
4317  *        all IO results in error
4318  *     When written, doesn't tear down array, but just stops it
4319  * suspended (not supported yet)
4320  *     All IO requests will block. The array can be reconfigured.
4321  *     Writing this, if accepted, will block until array is quiescent
4322  * readonly
4323  *     no resync can happen.  no superblocks get written.
4324  *     write requests fail
4325  * read-auto
4326  *     like readonly, but behaves like 'clean' on a write request.
4327  *
4328  * clean - no pending writes, but otherwise active.
4329  *     When written to inactive array, starts without resync
4330  *     If a write request arrives then
4331  *       if metadata is known, mark 'dirty' and switch to 'active'.
4332  *       if not known, block and switch to write-pending
4333  *     If written to an active array that has pending writes, then fails.
4334  * active
4335  *     fully active: IO and resync can be happening.
4336  *     When written to inactive array, starts with resync
4337  *
4338  * write-pending
4339  *     clean, but writes are blocked waiting for 'active' to be written.
4340  *
4341  * active-idle
4342  *     like active, but no writes have been seen for a while (100msec).
4343  *
4344  * broken
4345  *     RAID0/LINEAR-only: same as clean, but array is missing a member.
4346  *     It's useful because RAID0/LINEAR mounted-arrays aren't stopped
4347  *     when a member is gone, so this state will at least alert the
4348  *     user that something is wrong.
4349  */
4350 enum array_state { clear, inactive, suspended, readonly, read_auto, clean, active,
4351                    write_pending, active_idle, broken, bad_word};
4352 static char *array_states[] = {
4353         "clear", "inactive", "suspended", "readonly", "read-auto", "clean", "active",
4354         "write-pending", "active-idle", "broken", NULL };
4355
4356 static int match_word(const char *word, char **list)
4357 {
4358         int n;
4359         for (n=0; list[n]; n++)
4360                 if (cmd_match(word, list[n]))
4361                         break;
4362         return n;
4363 }
4364
4365 static ssize_t
4366 array_state_show(struct mddev *mddev, char *page)
4367 {
4368         enum array_state st = inactive;
4369
4370         if (mddev->pers && !test_bit(MD_NOT_READY, &mddev->flags)) {
4371                 switch(mddev->ro) {
4372                 case 1:
4373                         st = readonly;
4374                         break;
4375                 case 2:
4376                         st = read_auto;
4377                         break;
4378                 case 0:
4379                         spin_lock(&mddev->lock);
4380                         if (test_bit(MD_SB_CHANGE_PENDING, &mddev->sb_flags))
4381                                 st = write_pending;
4382                         else if (mddev->in_sync)
4383                                 st = clean;
4384                         else if (mddev->safemode)
4385                                 st = active_idle;
4386                         else
4387                                 st = active;
4388                         spin_unlock(&mddev->lock);
4389                 }
4390
4391                 if (test_bit(MD_BROKEN, &mddev->flags) && st == clean)
4392                         st = broken;
4393         } else {
4394                 if (list_empty(&mddev->disks) &&
4395                     mddev->raid_disks == 0 &&
4396                     mddev->dev_sectors == 0)
4397                         st = clear;
4398                 else
4399                         st = inactive;
4400         }
4401         return sprintf(page, "%s\n", array_states[st]);
4402 }
4403
4404 static int do_md_stop(struct mddev *mddev, int ro, struct block_device *bdev);
4405 static int md_set_readonly(struct mddev *mddev, struct block_device *bdev);
4406 static int restart_array(struct mddev *mddev);
4407
4408 static ssize_t
4409 array_state_store(struct mddev *mddev, const char *buf, size_t len)
4410 {
4411         int err = 0;
4412         enum array_state st = match_word(buf, array_states);
4413
4414         if (mddev->pers && (st == active || st == clean) && mddev->ro != 1) {
4415                 /* don't take reconfig_mutex when toggling between
4416                  * clean and active
4417                  */
4418                 spin_lock(&mddev->lock);
4419                 if (st == active) {
4420                         restart_array(mddev);
4421                         clear_bit(MD_SB_CHANGE_PENDING, &mddev->sb_flags);
4422                         md_wakeup_thread(mddev->thread);
4423                         wake_up(&mddev->sb_wait);
4424                 } else /* st == clean */ {
4425                         restart_array(mddev);
4426                         if (!set_in_sync(mddev))
4427                                 err = -EBUSY;
4428                 }
4429                 if (!err)
4430                         sysfs_notify_dirent_safe(mddev->sysfs_state);
4431                 spin_unlock(&mddev->lock);
4432                 return err ?: len;
4433         }
4434         err = mddev_lock(mddev);
4435         if (err)
4436                 return err;
4437         err = -EINVAL;
4438         switch(st) {
4439         case bad_word:
4440                 break;
4441         case clear:
4442                 /* stopping an active array */
4443                 err = do_md_stop(mddev, 0, NULL);
4444                 break;
4445         case inactive:
4446                 /* stopping an active array */
4447                 if (mddev->pers)
4448                         err = do_md_stop(mddev, 2, NULL);
4449                 else
4450                         err = 0; /* already inactive */
4451                 break;
4452         case suspended:
4453                 break; /* not supported yet */
4454         case readonly:
4455                 if (mddev->pers)
4456                         err = md_set_readonly(mddev, NULL);
4457                 else {
4458                         mddev->ro = 1;
4459                         set_disk_ro(mddev->gendisk, 1);
4460                         err = do_md_run(mddev);
4461                 }
4462                 break;
4463         case read_auto:
4464                 if (mddev->pers) {
4465                         if (mddev->ro == 0)
4466                                 err = md_set_readonly(mddev, NULL);
4467                         else if (mddev->ro == 1)
4468                                 err = restart_array(mddev);
4469                         if (err == 0) {
4470                                 mddev->ro = 2;
4471                                 set_disk_ro(mddev->gendisk, 0);
4472                         }
4473                 } else {
4474                         mddev->ro = 2;
4475                         err = do_md_run(mddev);
4476                 }
4477                 break;
4478         case clean:
4479                 if (mddev->pers) {
4480                         err = restart_array(mddev);
4481                         if (err)
4482                                 break;
4483                         spin_lock(&mddev->lock);
4484                         if (!set_in_sync(mddev))
4485                                 err = -EBUSY;
4486                         spin_unlock(&mddev->lock);
4487                 } else
4488                         err = -EINVAL;
4489                 break;
4490         case active:
4491                 if (mddev->pers) {
4492                         err = restart_array(mddev);
4493                         if (err)
4494                                 break;
4495                         clear_bit(MD_SB_CHANGE_PENDING, &mddev->sb_flags);
4496                         wake_up(&mddev->sb_wait);
4497                         err = 0;
4498                 } else {
4499                         mddev->ro = 0;
4500                         set_disk_ro(mddev->gendisk, 0);
4501                         err = do_md_run(mddev);
4502                 }
4503                 break;
4504         case write_pending:
4505         case active_idle:
4506         case broken:
4507                 /* these cannot be set */
4508                 break;
4509         }
4510
4511         if (!err) {
4512                 if (mddev->hold_active == UNTIL_IOCTL)
4513                         mddev->hold_active = 0;
4514                 sysfs_notify_dirent_safe(mddev->sysfs_state);
4515         }
4516         mddev_unlock(mddev);
4517         return err ?: len;
4518 }
4519 static struct md_sysfs_entry md_array_state =
4520 __ATTR_PREALLOC(array_state, S_IRUGO|S_IWUSR, array_state_show, array_state_store);
4521
4522 static ssize_t
4523 max_corrected_read_errors_show(struct mddev *mddev, char *page) {
4524         return sprintf(page, "%d\n",
4525                        atomic_read(&mddev->max_corr_read_errors));
4526 }
4527
4528 static ssize_t
4529 max_corrected_read_errors_store(struct mddev *mddev, const char *buf, size_t len)
4530 {
4531         unsigned int n;
4532         int rv;
4533
4534         rv = kstrtouint(buf, 10, &n);
4535         if (rv < 0)
4536                 return rv;
4537         atomic_set(&mddev->max_corr_read_errors, n);
4538         return len;
4539 }
4540
4541 static struct md_sysfs_entry max_corr_read_errors =
4542 __ATTR(max_read_errors, S_IRUGO|S_IWUSR, max_corrected_read_errors_show,
4543         max_corrected_read_errors_store);
4544
4545 static ssize_t
4546 null_show(struct mddev *mddev, char *page)
4547 {
4548         return -EINVAL;
4549 }
4550
4551 /* need to ensure rdev_delayed_delete() has completed */
4552 static void flush_rdev_wq(struct mddev *mddev)
4553 {
4554         struct md_rdev *rdev;
4555
4556         rcu_read_lock();
4557         rdev_for_each_rcu(rdev, mddev)
4558                 if (work_pending(&rdev->del_work)) {
4559                         flush_workqueue(md_rdev_misc_wq);
4560                         break;
4561                 }
4562         rcu_read_unlock();
4563 }
4564
4565 static ssize_t
4566 new_dev_store(struct mddev *mddev, const char *buf, size_t len)
4567 {
4568         /* buf must be %d:%d\n? giving major and minor numbers */
4569         /* The new device is added to the array.
4570          * If the array has a persistent superblock, we read the
4571          * superblock to initialise info and check validity.
4572          * Otherwise, only checking done is that in bind_rdev_to_array,
4573          * which mainly checks size.
4574          */
4575         char *e;
4576         int major = simple_strtoul(buf, &e, 10);
4577         int minor;
4578         dev_t dev;
4579         struct md_rdev *rdev;
4580         int err;
4581
4582         if (!*buf || *e != ':' || !e[1] || e[1] == '\n')
4583                 return -EINVAL;
4584         minor = simple_strtoul(e+1, &e, 10);
4585         if (*e && *e != '\n')
4586                 return -EINVAL;
4587         dev = MKDEV(major, minor);
4588         if (major != MAJOR(dev) ||
4589             minor != MINOR(dev))
4590                 return -EOVERFLOW;
4591
4592         flush_rdev_wq(mddev);
4593         err = mddev_lock(mddev);
4594         if (err)
4595                 return err;
4596         if (mddev->persistent) {
4597                 rdev = md_import_device(dev, mddev->major_version,
4598                                         mddev->minor_version);
4599                 if (!IS_ERR(rdev) && !list_empty(&mddev->disks)) {
4600                         struct md_rdev *rdev0
4601                                 = list_entry(mddev->disks.next,
4602                                              struct md_rdev, same_set);
4603                         err = super_types[mddev->major_version]
4604                                 .load_super(rdev, rdev0, mddev->minor_version);
4605                         if (err < 0)
4606                                 goto out;
4607                 }
4608         } else if (mddev->external)
4609                 rdev = md_import_device(dev, -2, -1);
4610         else
4611                 rdev = md_import_device(dev, -1, -1);
4612
4613         if (IS_ERR(rdev)) {
4614                 mddev_unlock(mddev);
4615                 return PTR_ERR(rdev);
4616         }
4617         err = bind_rdev_to_array(rdev, mddev);
4618  out:
4619         if (err)
4620                 export_rdev(rdev);
4621         mddev_unlock(mddev);
4622         if (!err)
4623                 md_new_event(mddev);
4624         return err ? err : len;
4625 }
4626
4627 static struct md_sysfs_entry md_new_device =
4628 __ATTR(new_dev, S_IWUSR, null_show, new_dev_store);
4629
4630 static ssize_t
4631 bitmap_store(struct mddev *mddev, const char *buf, size_t len)
4632 {
4633         char *end;
4634         unsigned long chunk, end_chunk;
4635         int err;
4636
4637         err = mddev_lock(mddev);
4638         if (err)
4639                 return err;
4640         if (!mddev->bitmap)
4641                 goto out;
4642         /* buf should be <chunk> <chunk> ... or <chunk>-<chunk> ... (range) */
4643         while (*buf) {
4644                 chunk = end_chunk = simple_strtoul(buf, &end, 0);
4645                 if (buf == end) break;
4646                 if (*end == '-') { /* range */
4647                         buf = end + 1;
4648                         end_chunk = simple_strtoul(buf, &end, 0);
4649                         if (buf == end) break;
4650                 }
4651                 if (*end && !isspace(*end)) break;
4652                 md_bitmap_dirty_bits(mddev->bitmap, chunk, end_chunk);
4653                 buf = skip_spaces(end);
4654         }
4655         md_bitmap_unplug(mddev->bitmap); /* flush the bits to disk */
4656 out:
4657         mddev_unlock(mddev);
4658         return len;
4659 }
4660
4661 static struct md_sysfs_entry md_bitmap =
4662 __ATTR(bitmap_set_bits, S_IWUSR, null_show, bitmap_store);
4663
4664 static ssize_t
4665 size_show(struct mddev *mddev, char *page)
4666 {
4667         return sprintf(page, "%llu\n",
4668                 (unsigned long long)mddev->dev_sectors / 2);
4669 }
4670
4671 static int update_size(struct mddev *mddev, sector_t num_sectors);
4672
4673 static ssize_t
4674 size_store(struct mddev *mddev, const char *buf, size_t len)
4675 {
4676         /* If array is inactive, we can reduce the component size, but
4677          * not increase it (except from 0).
4678          * If array is active, we can try an on-line resize
4679          */
4680         sector_t sectors;
4681         int err = strict_blocks_to_sectors(buf, &sectors);
4682
4683         if (err < 0)
4684                 return err;
4685         err = mddev_lock(mddev);
4686         if (err)
4687                 return err;
4688         if (mddev->pers) {
4689                 err = update_size(mddev, sectors);
4690                 if (err == 0)
4691                         md_update_sb(mddev, 1);
4692         } else {
4693                 if (mddev->dev_sectors == 0 ||
4694                     mddev->dev_sectors > sectors)
4695                         mddev->dev_sectors = sectors;
4696                 else
4697                         err = -ENOSPC;
4698         }
4699         mddev_unlock(mddev);
4700         return err ? err : len;
4701 }
4702
4703 static struct md_sysfs_entry md_size =
4704 __ATTR(component_size, S_IRUGO|S_IWUSR, size_show, size_store);
4705
4706 /* Metadata version.
4707  * This is one of
4708  *   'none' for arrays with no metadata (good luck...)
4709  *   'external' for arrays with externally managed metadata,
4710  * or N.M for internally known formats
4711  */
4712 static ssize_t
4713 metadata_show(struct mddev *mddev, char *page)
4714 {
4715         if (mddev->persistent)
4716                 return sprintf(page, "%d.%d\n",
4717                                mddev->major_version, mddev->minor_version);
4718         else if (mddev->external)
4719                 return sprintf(page, "external:%s\n", mddev->metadata_type);
4720         else
4721                 return sprintf(page, "none\n");
4722 }
4723
4724 static ssize_t
4725 metadata_store(struct mddev *mddev, const char *buf, size_t len)
4726 {
4727         int major, minor;
4728         char *e;
4729         int err;
4730         /* Changing the details of 'external' metadata is
4731          * always permitted.  Otherwise there must be
4732          * no devices attached to the array.
4733          */
4734
4735         err = mddev_lock(mddev);
4736         if (err)
4737                 return err;
4738         err = -EBUSY;
4739         if (mddev->external && strncmp(buf, "external:", 9) == 0)
4740                 ;
4741         else if (!list_empty(&mddev->disks))
4742                 goto out_unlock;
4743
4744         err = 0;
4745         if (cmd_match(buf, "none")) {
4746                 mddev->persistent = 0;
4747                 mddev->external = 0;
4748                 mddev->major_version = 0;
4749                 mddev->minor_version = 90;
4750                 goto out_unlock;
4751         }
4752         if (strncmp(buf, "external:", 9) == 0) {
4753                 size_t namelen = len-9;
4754                 if (namelen >= sizeof(mddev->metadata_type))
4755                         namelen = sizeof(mddev->metadata_type)-1;
4756                 strncpy(mddev->metadata_type, buf+9, namelen);
4757                 mddev->metadata_type[namelen] = 0;
4758                 if (namelen && mddev->metadata_type[namelen-1] == '\n')
4759                         mddev->metadata_type[--namelen] = 0;
4760                 mddev->persistent = 0;
4761                 mddev->external = 1;
4762                 mddev->major_version = 0;
4763                 mddev->minor_version = 90;
4764                 goto out_unlock;
4765         }
4766         major = simple_strtoul(buf, &e, 10);
4767         err = -EINVAL;
4768         if (e==buf || *e != '.')
4769                 goto out_unlock;
4770         buf = e+1;
4771         minor = simple_strtoul(buf, &e, 10);
4772         if (e==buf || (*e && *e != '\n') )
4773                 goto out_unlock;
4774         err = -ENOENT;
4775         if (major >= ARRAY_SIZE(super_types) || super_types[major].name == NULL)
4776                 goto out_unlock;
4777         mddev->major_version = major;
4778         mddev->minor_version = minor;
4779         mddev->persistent = 1;
4780         mddev->external = 0;
4781         err = 0;
4782 out_unlock:
4783         mddev_unlock(mddev);
4784         return err ?: len;
4785 }
4786
4787 static struct md_sysfs_entry md_metadata =
4788 __ATTR_PREALLOC(metadata_version, S_IRUGO|S_IWUSR, metadata_show, metadata_store);
4789
4790 static ssize_t
4791 action_show(struct mddev *mddev, char *page)
4792 {
4793         char *type = "idle";
4794         unsigned long recovery = mddev->recovery;
4795         if (test_bit(MD_RECOVERY_FROZEN, &recovery))
4796                 type = "frozen";
4797         else if (test_bit(MD_RECOVERY_RUNNING, &recovery) ||
4798             (!mddev->ro && test_bit(MD_RECOVERY_NEEDED, &recovery))) {
4799                 if (test_bit(MD_RECOVERY_RESHAPE, &recovery))
4800                         type = "reshape";
4801                 else if (test_bit(MD_RECOVERY_SYNC, &recovery)) {
4802                         if (!test_bit(MD_RECOVERY_REQUESTED, &recovery))
4803                                 type = "resync";
4804                         else if (test_bit(MD_RECOVERY_CHECK, &recovery))
4805                                 type = "check";
4806                         else
4807                                 type = "repair";
4808                 } else if (test_bit(MD_RECOVERY_RECOVER, &recovery))
4809                         type = "recover";
4810                 else if (mddev->reshape_position != MaxSector)
4811                         type = "reshape";
4812         }
4813         return sprintf(page, "%s\n", type);
4814 }
4815
4816 static ssize_t
4817 action_store(struct mddev *mddev, const char *page, size_t len)
4818 {
4819         if (!mddev->pers || !mddev->pers->sync_request)
4820                 return -EINVAL;
4821
4822
4823         if (cmd_match(page, "idle") || cmd_match(page, "frozen")) {
4824                 if (cmd_match(page, "frozen"))
4825                         set_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
4826                 else
4827                         clear_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
4828                 if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery) &&
4829                     mddev_lock(mddev) == 0) {
4830                         if (work_pending(&mddev->del_work))
4831                                 flush_workqueue(md_misc_wq);
4832                         if (mddev->sync_thread) {
4833                                 set_bit(MD_RECOVERY_INTR, &mddev->recovery);
4834                                 md_reap_sync_thread(mddev);
4835                         }
4836                         mddev_unlock(mddev);
4837                 }
4838         } else if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery))
4839                 return -EBUSY;
4840         else if (cmd_match(page, "resync"))
4841                 clear_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
4842         else if (cmd_match(page, "recover")) {
4843                 clear_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
4844                 set_bit(MD_RECOVERY_RECOVER, &mddev->recovery);
4845         } else if (cmd_match(page, "reshape")) {
4846                 int err;
4847                 if (mddev->pers->start_reshape == NULL)
4848                         return -EINVAL;
4849                 err = mddev_lock(mddev);
4850                 if (!err) {
4851                         if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery))
4852                                 err =  -EBUSY;
4853                         else {
4854                                 clear_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
4855                                 err = mddev->pers->start_reshape(mddev);
4856                         }
4857                         mddev_unlock(mddev);
4858                 }
4859                 if (err)
4860                         return err;
4861                 sysfs_notify_dirent_safe(mddev->sysfs_degraded);
4862         } else {
4863                 if (cmd_match(page, "check"))
4864                         set_bit(MD_RECOVERY_CHECK, &mddev->recovery);
4865                 else if (!cmd_match(page, "repair"))
4866                         return -EINVAL;
4867                 clear_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
4868                 set_bit(MD_RECOVERY_REQUESTED, &mddev->recovery);
4869                 set_bit(MD_RECOVERY_SYNC, &mddev->recovery);
4870         }
4871         if (mddev->ro == 2) {
4872                 /* A write to sync_action is enough to justify
4873                  * canceling read-auto mode
4874                  */
4875                 mddev->ro = 0;
4876                 md_wakeup_thread(mddev->sync_thread);
4877         }
4878         set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
4879         md_wakeup_thread(mddev->thread);
4880         sysfs_notify_dirent_safe(mddev->sysfs_action);
4881         return len;
4882 }
4883
4884 static struct md_sysfs_entry md_scan_mode =
4885 __ATTR_PREALLOC(sync_action, S_IRUGO|S_IWUSR, action_show, action_store);
4886
4887 static ssize_t
4888 last_sync_action_show(struct mddev *mddev, char *page)
4889 {
4890         return sprintf(page, "%s\n", mddev->last_sync_action);
4891 }
4892
4893 static struct md_sysfs_entry md_last_scan_mode = __ATTR_RO(last_sync_action);
4894
4895 static ssize_t
4896 mismatch_cnt_show(struct mddev *mddev, char *page)
4897 {
4898         return sprintf(page, "%llu\n",
4899                        (unsigned long long)
4900                        atomic64_read(&mddev->resync_mismatches));
4901 }
4902
4903 static struct md_sysfs_entry md_mismatches = __ATTR_RO(mismatch_cnt);
4904
4905 static ssize_t
4906 sync_min_show(struct mddev *mddev, char *page)
4907 {
4908         return sprintf(page, "%d (%s)\n", speed_min(mddev),
4909                        mddev->sync_speed_min ? "local": "system");
4910 }
4911
4912 static ssize_t
4913 sync_min_store(struct mddev *mddev, const char *buf, size_t len)
4914 {
4915         unsigned int min;
4916         int rv;
4917
4918         if (strncmp(buf, "system", 6)==0) {
4919                 min = 0;
4920         } else {
4921                 rv = kstrtouint(buf, 10, &min);
4922                 if (rv < 0)
4923                         return rv;
4924                 if (min == 0)
4925                         return -EINVAL;
4926         }
4927         mddev->sync_speed_min = min;
4928         return len;
4929 }
4930
4931 static struct md_sysfs_entry md_sync_min =
4932 __ATTR(sync_speed_min, S_IRUGO|S_IWUSR, sync_min_show, sync_min_store);
4933
4934 static ssize_t
4935 sync_max_show(struct mddev *mddev, char *page)
4936 {
4937         return sprintf(page, "%d (%s)\n", speed_max(mddev),
4938                        mddev->sync_speed_max ? "local": "system");
4939 }
4940
4941 static ssize_t
4942 sync_max_store(struct mddev *mddev, const char *buf, size_t len)
4943 {
4944         unsigned int max;
4945         int rv;
4946
4947         if (strncmp(buf, "system", 6)==0) {
4948                 max = 0;
4949         } else {
4950                 rv = kstrtouint(buf, 10, &max);
4951                 if (rv < 0)
4952                         return rv;
4953                 if (max == 0)
4954                         return -EINVAL;
4955         }
4956         mddev->sync_speed_max = max;
4957         return len;
4958 }
4959
4960 static struct md_sysfs_entry md_sync_max =
4961 __ATTR(sync_speed_max, S_IRUGO|S_IWUSR, sync_max_show, sync_max_store);
4962
4963 static ssize_t
4964 degraded_show(struct mddev *mddev, char *page)
4965 {
4966         return sprintf(page, "%d\n", mddev->degraded);
4967 }
4968 static struct md_sysfs_entry md_degraded = __ATTR_RO(degraded);
4969
4970 static ssize_t
4971 sync_force_parallel_show(struct mddev *mddev, char *page)
4972 {
4973         return sprintf(page, "%d\n", mddev->parallel_resync);
4974 }
4975
4976 static ssize_t
4977 sync_force_parallel_store(struct mddev *mddev, const char *buf, size_t len)
4978 {
4979         long n;
4980
4981         if (kstrtol(buf, 10, &n))
4982                 return -EINVAL;
4983
4984         if (n != 0 && n != 1)
4985                 return -EINVAL;
4986
4987         mddev->parallel_resync = n;
4988
4989         if (mddev->sync_thread)
4990                 wake_up(&resync_wait);
4991
4992         return len;
4993 }
4994
4995 /* force parallel resync, even with shared block devices */
4996 static struct md_sysfs_entry md_sync_force_parallel =
4997 __ATTR(sync_force_parallel, S_IRUGO|S_IWUSR,
4998        sync_force_parallel_show, sync_force_parallel_store);
4999
5000 static ssize_t
5001 sync_speed_show(struct mddev *mddev, char *page)
5002 {
5003         unsigned long resync, dt, db;
5004         if (mddev->curr_resync == 0)
5005                 return sprintf(page, "none\n");
5006         resync = mddev->curr_mark_cnt - atomic_read(&mddev->recovery_active);
5007         dt = (jiffies - mddev->resync_mark) / HZ;
5008         if (!dt) dt++;
5009         db = resync - mddev->resync_mark_cnt;
5010         return sprintf(page, "%lu\n", db/dt/2); /* K/sec */
5011 }
5012
5013 static struct md_sysfs_entry md_sync_speed = __ATTR_RO(sync_speed);
5014
5015 static ssize_t
5016 sync_completed_show(struct mddev *mddev, char *page)
5017 {
5018         unsigned long long max_sectors, resync;
5019
5020         if (!test_bit(MD_RECOVERY_RUNNING, &mddev->recovery))
5021                 return sprintf(page, "none\n");
5022
5023         if (mddev->curr_resync == 1 ||
5024             mddev->curr_resync == 2)
5025                 return sprintf(page, "delayed\n");
5026
5027         if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery) ||
5028             test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery))
5029                 max_sectors = mddev->resync_max_sectors;
5030         else
5031                 max_sectors = mddev->dev_sectors;
5032
5033         resync = mddev->curr_resync_completed;
5034         return sprintf(page, "%llu / %llu\n", resync, max_sectors);
5035 }
5036
5037 static struct md_sysfs_entry md_sync_completed =
5038         __ATTR_PREALLOC(sync_completed, S_IRUGO, sync_completed_show, NULL);
5039
5040 static ssize_t
5041 min_sync_show(struct mddev *mddev, char *page)
5042 {
5043         return sprintf(page, "%llu\n",
5044                        (unsigned long long)mddev->resync_min);
5045 }
5046 static ssize_t
5047 min_sync_store(struct mddev *mddev, const char *buf, size_t len)
5048 {
5049         unsigned long long min;
5050         int err;
5051
5052         if (kstrtoull(buf, 10, &min))
5053                 return -EINVAL;
5054
5055         spin_lock(&mddev->lock);
5056         err = -EINVAL;
5057         if (min > mddev->resync_max)
5058                 goto out_unlock;
5059
5060         err = -EBUSY;
5061         if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery))
5062                 goto out_unlock;
5063
5064         /* Round down to multiple of 4K for safety */
5065         mddev->resync_min = round_down(min, 8);
5066         err = 0;
5067
5068 out_unlock:
5069         spin_unlock(&mddev->lock);
5070         return err ?: len;
5071 }
5072
5073 static struct md_sysfs_entry md_min_sync =
5074 __ATTR(sync_min, S_IRUGO|S_IWUSR, min_sync_show, min_sync_store);
5075
5076 static ssize_t
5077 max_sync_show(struct mddev *mddev, char *page)
5078 {
5079         if (mddev->resync_max == MaxSector)
5080                 return sprintf(page, "max\n");
5081         else
5082                 return sprintf(page, "%llu\n",
5083                                (unsigned long long)mddev->resync_max);
5084 }
5085 static ssize_t
5086 max_sync_store(struct mddev *mddev, const char *buf, size_t len)
5087 {
5088         int err;
5089         spin_lock(&mddev->lock);
5090         if (strncmp(buf, "max", 3) == 0)
5091                 mddev->resync_max = MaxSector;
5092         else {
5093                 unsigned long long max;
5094                 int chunk;
5095
5096                 err = -EINVAL;
5097                 if (kstrtoull(buf, 10, &max))
5098                         goto out_unlock;
5099                 if (max < mddev->resync_min)
5100                         goto out_unlock;
5101
5102                 err = -EBUSY;
5103                 if (max < mddev->resync_max &&
5104                     mddev->ro == 0 &&
5105                     test_bit(MD_RECOVERY_RUNNING, &mddev->recovery))
5106                         goto out_unlock;
5107
5108                 /* Must be a multiple of chunk_size */
5109                 chunk = mddev->chunk_sectors;
5110                 if (chunk) {
5111                         sector_t temp = max;
5112
5113                         err = -EINVAL;
5114                         if (sector_div(temp, chunk))
5115                                 goto out_unlock;
5116                 }
5117                 mddev->resync_max = max;
5118         }
5119         wake_up(&mddev->recovery_wait);
5120         err = 0;
5121 out_unlock:
5122         spin_unlock(&mddev->lock);
5123         return err ?: len;
5124 }
5125
5126 static struct md_sysfs_entry md_max_sync =
5127 __ATTR(sync_max, S_IRUGO|S_IWUSR, max_sync_show, max_sync_store);
5128
5129 static ssize_t
5130 suspend_lo_show(struct mddev *mddev, char *page)
5131 {
5132         return sprintf(page, "%llu\n", (unsigned long long)mddev->suspend_lo);
5133 }
5134
5135 static ssize_t
5136 suspend_lo_store(struct mddev *mddev, const char *buf, size_t len)
5137 {
5138         unsigned long long new;
5139         int err;
5140
5141         err = kstrtoull(buf, 10, &new);
5142         if (err < 0)
5143                 return err;
5144         if (new != (sector_t)new)
5145                 return -EINVAL;
5146
5147         err = mddev_lock(mddev);
5148         if (err)
5149                 return err;
5150         err = -EINVAL;
5151         if (mddev->pers == NULL ||
5152             mddev->pers->quiesce == NULL)
5153                 goto unlock;
5154         mddev_suspend(mddev);
5155         mddev->suspend_lo = new;
5156         mddev_resume(mddev);
5157
5158         err = 0;
5159 unlock:
5160         mddev_unlock(mddev);
5161         return err ?: len;
5162 }
5163 static struct md_sysfs_entry md_suspend_lo =
5164 __ATTR(suspend_lo, S_IRUGO|S_IWUSR, suspend_lo_show, suspend_lo_store);
5165
5166 static ssize_t
5167 suspend_hi_show(struct mddev *mddev, char *page)
5168 {
5169         return sprintf(page, "%llu\n", (unsigned long long)mddev->suspend_hi);
5170 }
5171
5172 static ssize_t
5173 suspend_hi_store(struct mddev *mddev, const char *buf, size_t len)
5174 {
5175         unsigned long long new;
5176         int err;
5177
5178         err = kstrtoull(buf, 10, &new);
5179         if (err < 0)
5180                 return err;
5181         if (new != (sector_t)new)
5182                 return -EINVAL;
5183
5184         err = mddev_lock(mddev);
5185         if (err)
5186                 return err;
5187         err = -EINVAL;
5188         if (mddev->pers == NULL)
5189                 goto unlock;
5190
5191         mddev_suspend(mddev);
5192         mddev->suspend_hi = new;
5193         mddev_resume(mddev);
5194
5195         err = 0;
5196 unlock:
5197         mddev_unlock(mddev);
5198         return err ?: len;
5199 }
5200 static struct md_sysfs_entry md_suspend_hi =
5201 __ATTR(suspend_hi, S_IRUGO|S_IWUSR, suspend_hi_show, suspend_hi_store);
5202
5203 static ssize_t
5204 reshape_position_show(struct mddev *mddev, char *page)
5205 {
5206         if (mddev->reshape_position != MaxSector)
5207                 return sprintf(page, "%llu\n",
5208                                (unsigned long long)mddev->reshape_position);
5209         strcpy(page, "none\n");
5210         return 5;
5211 }
5212
5213 static ssize_t
5214 reshape_position_store(struct mddev *mddev, const char *buf, size_t len)
5215 {
5216         struct md_rdev *rdev;
5217         unsigned long long new;
5218         int err;
5219
5220         err = kstrtoull(buf, 10, &new);
5221         if (err < 0)
5222                 return err;
5223         if (new != (sector_t)new)
5224                 return -EINVAL;
5225         err = mddev_lock(mddev);
5226         if (err)
5227                 return err;
5228         err = -EBUSY;
5229         if (mddev->pers)
5230                 goto unlock;
5231         mddev->reshape_position = new;
5232         mddev->delta_disks = 0;
5233         mddev->reshape_backwards = 0;
5234         mddev->new_level = mddev->level;
5235         mddev->new_layout = mddev->layout;
5236         mddev->new_chunk_sectors = mddev->chunk_sectors;
5237         rdev_for_each(rdev, mddev)
5238                 rdev->new_data_offset = rdev->data_offset;
5239         err = 0;
5240 unlock:
5241         mddev_unlock(mddev);
5242         return err ?: len;
5243 }
5244
5245 static struct md_sysfs_entry md_reshape_position =
5246 __ATTR(reshape_position, S_IRUGO|S_IWUSR, reshape_position_show,
5247        reshape_position_store);
5248
5249 static ssize_t
5250 reshape_direction_show(struct mddev *mddev, char *page)
5251 {
5252         return sprintf(page, "%s\n",
5253                        mddev->reshape_backwards ? "backwards" : "forwards");
5254 }
5255
5256 static ssize_t
5257 reshape_direction_store(struct mddev *mddev, const char *buf, size_t len)
5258 {
5259         int backwards = 0;
5260         int err;
5261
5262         if (cmd_match(buf, "forwards"))
5263                 backwards = 0;
5264         else if (cmd_match(buf, "backwards"))
5265                 backwards = 1;
5266         else
5267                 return -EINVAL;
5268         if (mddev->reshape_backwards == backwards)
5269                 return len;
5270
5271         err = mddev_lock(mddev);
5272         if (err)
5273                 return err;
5274         /* check if we are allowed to change */
5275         if (mddev->delta_disks)
5276                 err = -EBUSY;
5277         else if (mddev->persistent &&
5278             mddev->major_version == 0)
5279                 err =  -EINVAL;
5280         else
5281                 mddev->reshape_backwards = backwards;
5282         mddev_unlock(mddev);
5283         return err ?: len;
5284 }
5285
5286 static struct md_sysfs_entry md_reshape_direction =
5287 __ATTR(reshape_direction, S_IRUGO|S_IWUSR, reshape_direction_show,
5288        reshape_direction_store);
5289
5290 static ssize_t
5291 array_size_show(struct mddev *mddev, char *page)
5292 {
5293         if (mddev->external_size)
5294                 return sprintf(page, "%llu\n",
5295                                (unsigned long long)mddev->array_sectors/2);
5296         else
5297                 return sprintf(page, "default\n");
5298 }
5299
5300 static ssize_t
5301 array_size_store(struct mddev *mddev, const char *buf, size_t len)
5302 {
5303         sector_t sectors;
5304         int err;
5305
5306         err = mddev_lock(mddev);
5307         if (err)
5308                 return err;
5309
5310         /* cluster raid doesn't support change array_sectors */
5311         if (mddev_is_clustered(mddev)) {
5312                 mddev_unlock(mddev);
5313                 return -EINVAL;
5314         }
5315
5316         if (strncmp(buf, "default", 7) == 0) {
5317                 if (mddev->pers)
5318                         sectors = mddev->pers->size(mddev, 0, 0);
5319                 else
5320                         sectors = mddev->array_sectors;
5321
5322                 mddev->external_size = 0;
5323         } else {
5324                 if (strict_blocks_to_sectors(buf, &sectors) < 0)
5325                         err = -EINVAL;
5326                 else if (mddev->pers && mddev->pers->size(mddev, 0, 0) < sectors)
5327                         err = -E2BIG;
5328                 else
5329                         mddev->external_size = 1;
5330         }
5331
5332         if (!err) {
5333                 mddev->array_sectors = sectors;
5334                 if (mddev->pers)
5335                         set_capacity_and_notify(mddev->gendisk,
5336                                                 mddev->array_sectors);
5337         }
5338         mddev_unlock(mddev);
5339         return err ?: len;
5340 }
5341
5342 static struct md_sysfs_entry md_array_size =
5343 __ATTR(array_size, S_IRUGO|S_IWUSR, array_size_show,
5344        array_size_store);
5345
5346 static ssize_t
5347 consistency_policy_show(struct mddev *mddev, char *page)
5348 {
5349         int ret;
5350
5351         if (test_bit(MD_HAS_JOURNAL, &mddev->flags)) {
5352                 ret = sprintf(page, "journal\n");
5353         } else if (test_bit(MD_HAS_PPL, &mddev->flags)) {
5354                 ret = sprintf(page, "ppl\n");
5355         } else if (mddev->bitmap) {
5356                 ret = sprintf(page, "bitmap\n");
5357         } else if (mddev->pers) {
5358                 if (mddev->pers->sync_request)
5359                         ret = sprintf(page, "resync\n");
5360                 else
5361                         ret = sprintf(page, "none\n");
5362         } else {
5363                 ret = sprintf(page, "unknown\n");
5364         }
5365
5366         return ret;
5367 }
5368
5369 static ssize_t
5370 consistency_policy_store(struct mddev *mddev, const char *buf, size_t len)
5371 {
5372         int err = 0;
5373
5374         if (mddev->pers) {
5375                 if (mddev->pers->change_consistency_policy)
5376                         err = mddev->pers->change_consistency_policy(mddev, buf);
5377                 else
5378                         err = -EBUSY;
5379         } else if (mddev->external && strncmp(buf, "ppl", 3) == 0) {
5380                 set_bit(MD_HAS_PPL, &mddev->flags);
5381         } else {
5382                 err = -EINVAL;
5383         }
5384
5385         return err ? err : len;
5386 }
5387
5388 static struct md_sysfs_entry md_consistency_policy =
5389 __ATTR(consistency_policy, S_IRUGO | S_IWUSR, consistency_policy_show,
5390        consistency_policy_store);
5391
5392 static ssize_t fail_last_dev_show(struct mddev *mddev, char *page)
5393 {
5394         return sprintf(page, "%d\n", mddev->fail_last_dev);
5395 }
5396
5397 /*
5398  * Setting fail_last_dev to true to allow last device to be forcibly removed
5399  * from RAID1/RAID10.
5400  */
5401 static ssize_t
5402 fail_last_dev_store(struct mddev *mddev, const char *buf, size_t len)
5403 {
5404         int ret;
5405         bool value;
5406
5407         ret = kstrtobool(buf, &value);
5408         if (ret)
5409                 return ret;
5410
5411         if (value != mddev->fail_last_dev)
5412                 mddev->fail_last_dev = value;
5413
5414         return len;
5415 }
5416 static struct md_sysfs_entry md_fail_last_dev =
5417 __ATTR(fail_last_dev, S_IRUGO | S_IWUSR, fail_last_dev_show,
5418        fail_last_dev_store);
5419
5420 static ssize_t serialize_policy_show(struct mddev *mddev, char *page)
5421 {
5422         if (mddev->pers == NULL || (mddev->pers->level != 1))
5423                 return sprintf(page, "n/a\n");
5424         else
5425                 return sprintf(page, "%d\n", mddev->serialize_policy);
5426 }
5427
5428 /*
5429  * Setting serialize_policy to true to enforce write IO is not reordered
5430  * for raid1.
5431  */
5432 static ssize_t
5433 serialize_policy_store(struct mddev *mddev, const char *buf, size_t len)
5434 {
5435         int err;
5436         bool value;
5437
5438         err = kstrtobool(buf, &value);
5439         if (err)
5440                 return err;
5441
5442         if (value == mddev->serialize_policy)
5443                 return len;
5444
5445         err = mddev_lock(mddev);
5446         if (err)
5447                 return err;
5448         if (mddev->pers == NULL || (mddev->pers->level != 1)) {
5449                 pr_err("md: serialize_policy is only effective for raid1\n");
5450                 err = -EINVAL;
5451                 goto unlock;
5452         }
5453
5454         mddev_suspend(mddev);
5455         if (value)
5456                 mddev_create_serial_pool(mddev, NULL, true);
5457         else
5458                 mddev_destroy_serial_pool(mddev, NULL, true);
5459         mddev->serialize_policy = value;
5460         mddev_resume(mddev);
5461 unlock:
5462         mddev_unlock(mddev);
5463         return err ?: len;
5464 }
5465
5466 static struct md_sysfs_entry md_serialize_policy =
5467 __ATTR(serialize_policy, S_IRUGO | S_IWUSR, serialize_policy_show,
5468        serialize_policy_store);
5469
5470
5471 static struct attribute *md_default_attrs[] = {
5472         &md_level.attr,
5473         &md_layout.attr,
5474         &md_raid_disks.attr,
5475         &md_uuid.attr,
5476         &md_chunk_size.attr,
5477         &md_size.attr,
5478         &md_resync_start.attr,
5479         &md_metadata.attr,
5480         &md_new_device.attr,
5481         &md_safe_delay.attr,
5482         &md_array_state.attr,
5483         &md_reshape_position.attr,
5484         &md_reshape_direction.attr,
5485         &md_array_size.attr,
5486         &max_corr_read_errors.attr,
5487         &md_consistency_policy.attr,
5488         &md_fail_last_dev.attr,
5489         &md_serialize_policy.attr,
5490         NULL,
5491 };
5492
5493 static struct attribute *md_redundancy_attrs[] = {
5494         &md_scan_mode.attr,
5495         &md_last_scan_mode.attr,
5496         &md_mismatches.attr,
5497         &md_sync_min.attr,
5498         &md_sync_max.attr,
5499         &md_sync_speed.attr,
5500         &md_sync_force_parallel.attr,
5501         &md_sync_completed.attr,
5502         &md_min_sync.attr,
5503         &md_max_sync.attr,
5504         &md_suspend_lo.attr,
5505         &md_suspend_hi.attr,
5506         &md_bitmap.attr,
5507         &md_degraded.attr,
5508         NULL,
5509 };
5510 static const struct attribute_group md_redundancy_group = {
5511         .name = NULL,
5512         .attrs = md_redundancy_attrs,
5513 };
5514
5515 static ssize_t
5516 md_attr_show(struct kobject *kobj, struct attribute *attr, char *page)
5517 {
5518         struct md_sysfs_entry *entry = container_of(attr, struct md_sysfs_entry, attr);
5519         struct mddev *mddev = container_of(kobj, struct mddev, kobj);
5520         ssize_t rv;
5521
5522         if (!entry->show)
5523                 return -EIO;
5524         spin_lock(&all_mddevs_lock);
5525         if (list_empty(&mddev->all_mddevs)) {
5526                 spin_unlock(&all_mddevs_lock);
5527                 return -EBUSY;
5528         }
5529         mddev_get(mddev);
5530         spin_unlock(&all_mddevs_lock);
5531
5532         rv = entry->show(mddev, page);
5533         mddev_put(mddev);
5534         return rv;
5535 }
5536
5537 static ssize_t
5538 md_attr_store(struct kobject *kobj, struct attribute *attr,
5539               const char *page, size_t length)
5540 {
5541         struct md_sysfs_entry *entry = container_of(attr, struct md_sysfs_entry, attr);
5542         struct mddev *mddev = container_of(kobj, struct mddev, kobj);
5543         ssize_t rv;
5544
5545         if (!entry->store)
5546                 return -EIO;
5547         if (!capable(CAP_SYS_ADMIN))
5548                 return -EACCES;
5549         spin_lock(&all_mddevs_lock);
5550         if (list_empty(&mddev->all_mddevs)) {
5551                 spin_unlock(&all_mddevs_lock);
5552                 return -EBUSY;
5553         }
5554         mddev_get(mddev);
5555         spin_unlock(&all_mddevs_lock);
5556         rv = entry->store(mddev, page, length);
5557         mddev_put(mddev);
5558         return rv;
5559 }
5560
5561 static void md_free(struct kobject *ko)
5562 {
5563         struct mddev *mddev = container_of(ko, struct mddev, kobj);
5564
5565         if (mddev->sysfs_state)
5566                 sysfs_put(mddev->sysfs_state);
5567         if (mddev->sysfs_level)
5568                 sysfs_put(mddev->sysfs_level);
5569
5570         if (mddev->gendisk) {
5571                 del_gendisk(mddev->gendisk);
5572                 blk_cleanup_disk(mddev->gendisk);
5573         }
5574         percpu_ref_exit(&mddev->writes_pending);
5575
5576         bioset_exit(&mddev->bio_set);
5577         bioset_exit(&mddev->sync_set);
5578         if (mddev->level != 1 && mddev->level != 10)
5579                 bioset_exit(&mddev->io_acct_set);
5580         kfree(mddev);
5581 }
5582
5583 static const struct sysfs_ops md_sysfs_ops = {
5584         .show   = md_attr_show,
5585         .store  = md_attr_store,
5586 };
5587 static struct kobj_type md_ktype = {
5588         .release        = md_free,
5589         .sysfs_ops      = &md_sysfs_ops,
5590         .default_attrs  = md_default_attrs,
5591 };
5592
5593 int mdp_major = 0;
5594
5595 static void mddev_delayed_delete(struct work_struct *ws)
5596 {
5597         struct mddev *mddev = container_of(ws, struct mddev, del_work);
5598
5599         sysfs_remove_group(&mddev->kobj, &md_bitmap_group);
5600         kobject_del(&mddev->kobj);
5601         kobject_put(&mddev->kobj);
5602 }
5603
5604 static void no_op(struct percpu_ref *r) {}
5605
5606 int mddev_init_writes_pending(struct mddev *mddev)
5607 {
5608         if (mddev->writes_pending.percpu_count_ptr)
5609                 return 0;
5610         if (percpu_ref_init(&mddev->writes_pending, no_op,
5611                             PERCPU_REF_ALLOW_REINIT, GFP_KERNEL) < 0)
5612                 return -ENOMEM;
5613         /* We want to start with the refcount at zero */
5614         percpu_ref_put(&mddev->writes_pending);
5615         return 0;
5616 }
5617 EXPORT_SYMBOL_GPL(mddev_init_writes_pending);
5618
5619 static int md_alloc(dev_t dev, char *name)
5620 {
5621         /*
5622          * If dev is zero, name is the name of a device to allocate with
5623          * an arbitrary minor number.  It will be "md_???"
5624          * If dev is non-zero it must be a device number with a MAJOR of
5625          * MD_MAJOR or mdp_major.  In this case, if "name" is NULL, then
5626          * the device is being created by opening a node in /dev.
5627          * If "name" is not NULL, the device is being created by
5628          * writing to /sys/module/md_mod/parameters/new_array.
5629          */
5630         static DEFINE_MUTEX(disks_mutex);
5631         struct mddev *mddev;
5632         struct gendisk *disk;
5633         int partitioned;
5634         int shift;
5635         int unit;
5636         int error ;
5637
5638         /*
5639          * Wait for any previous instance of this device to be completely
5640          * removed (mddev_delayed_delete).
5641          */
5642         flush_workqueue(md_misc_wq);
5643
5644         mutex_lock(&disks_mutex);
5645         mddev = mddev_alloc(dev);
5646         if (IS_ERR(mddev)) {
5647                 mutex_unlock(&disks_mutex);
5648                 return PTR_ERR(mddev);
5649         }
5650
5651         partitioned = (MAJOR(mddev->unit) != MD_MAJOR);
5652         shift = partitioned ? MdpMinorShift : 0;
5653         unit = MINOR(mddev->unit) >> shift;
5654
5655         if (name && !dev) {
5656                 /* Need to ensure that 'name' is not a duplicate.
5657                  */
5658                 struct mddev *mddev2;
5659                 spin_lock(&all_mddevs_lock);
5660
5661                 list_for_each_entry(mddev2, &all_mddevs, all_mddevs)
5662                         if (mddev2->gendisk &&
5663                             strcmp(mddev2->gendisk->disk_name, name) == 0) {
5664                                 spin_unlock(&all_mddevs_lock);
5665                                 error = -EEXIST;
5666                                 goto abort;
5667                         }
5668                 spin_unlock(&all_mddevs_lock);
5669         }
5670         if (name && dev)
5671                 /*
5672                  * Creating /dev/mdNNN via "newarray", so adjust hold_active.
5673                  */
5674                 mddev->hold_active = UNTIL_STOP;
5675
5676         error = -ENOMEM;
5677         disk = blk_alloc_disk(NUMA_NO_NODE);
5678         if (!disk)
5679                 goto abort;
5680
5681         disk->major = MAJOR(mddev->unit);
5682         disk->first_minor = unit << shift;
5683         disk->minors = 1 << shift;
5684         if (name)
5685                 strcpy(disk->disk_name, name);
5686         else if (partitioned)
5687                 sprintf(disk->disk_name, "md_d%d", unit);
5688         else
5689                 sprintf(disk->disk_name, "md%d", unit);
5690         disk->fops = &md_fops;
5691         disk->private_data = mddev;
5692
5693         mddev->queue = disk->queue;
5694         blk_set_stacking_limits(&mddev->queue->limits);
5695         blk_queue_write_cache(mddev->queue, true, true);
5696         /* Allow extended partitions.  This makes the
5697          * 'mdp' device redundant, but we can't really
5698          * remove it now.
5699          */
5700         disk->flags |= GENHD_FL_EXT_DEVT;
5701         disk->events |= DISK_EVENT_MEDIA_CHANGE;
5702         mddev->gendisk = disk;
5703         add_disk(disk);
5704
5705         error = kobject_add(&mddev->kobj, &disk_to_dev(disk)->kobj, "%s", "md");
5706         if (error) {
5707                 /* This isn't possible, but as kobject_init_and_add is marked
5708                  * __must_check, we must do something with the result
5709                  */
5710                 pr_debug("md: cannot register %s/md - name in use\n",
5711                          disk->disk_name);
5712                 error = 0;
5713         }
5714         if (mddev->kobj.sd &&
5715             sysfs_create_group(&mddev->kobj, &md_bitmap_group))
5716                 pr_debug("pointless warning\n");
5717  abort:
5718         mutex_unlock(&disks_mutex);
5719         if (!error && mddev->kobj.sd) {
5720                 kobject_uevent(&mddev->kobj, KOBJ_ADD);
5721                 mddev->sysfs_state = sysfs_get_dirent_safe(mddev->kobj.sd, "array_state");
5722                 mddev->sysfs_level = sysfs_get_dirent_safe(mddev->kobj.sd, "level");
5723         }
5724         mddev_put(mddev);
5725         return error;
5726 }
5727
5728 static void md_probe(dev_t dev)
5729 {
5730         if (MAJOR(dev) == MD_MAJOR && MINOR(dev) >= 512)
5731                 return;
5732         if (create_on_open)
5733                 md_alloc(dev, NULL);
5734 }
5735
5736 static int add_named_array(const char *val, const struct kernel_param *kp)
5737 {
5738         /*
5739          * val must be "md_*" or "mdNNN".
5740          * For "md_*" we allocate an array with a large free minor number, and
5741          * set the name to val.  val must not already be an active name.
5742          * For "mdNNN" we allocate an array with the minor number NNN
5743          * which must not already be in use.
5744          */
5745         int len = strlen(val);
5746         char buf[DISK_NAME_LEN];
5747         unsigned long devnum;
5748
5749         while (len && val[len-1] == '\n')
5750                 len--;
5751         if (len >= DISK_NAME_LEN)
5752                 return -E2BIG;
5753         strlcpy(buf, val, len+1);
5754         if (strncmp(buf, "md_", 3) == 0)
5755                 return md_alloc(0, buf);
5756         if (strncmp(buf, "md", 2) == 0 &&
5757             isdigit(buf[2]) &&
5758             kstrtoul(buf+2, 10, &devnum) == 0 &&
5759             devnum <= MINORMASK)
5760                 return md_alloc(MKDEV(MD_MAJOR, devnum), NULL);
5761
5762         return -EINVAL;
5763 }
5764
5765 static void md_safemode_timeout(struct timer_list *t)
5766 {
5767         struct mddev *mddev = from_timer(mddev, t, safemode_timer);
5768
5769         mddev->safemode = 1;
5770         if (mddev->external)
5771                 sysfs_notify_dirent_safe(mddev->sysfs_state);
5772
5773         md_wakeup_thread(mddev->thread);
5774 }
5775
5776 static int start_dirty_degraded;
5777
5778 int md_run(struct mddev *mddev)
5779 {
5780         int err;
5781         struct md_rdev *rdev;
5782         struct md_personality *pers;
5783
5784         if (list_empty(&mddev->disks))
5785                 /* cannot run an array with no devices.. */
5786                 return -EINVAL;
5787
5788         if (mddev->pers)
5789                 return -EBUSY;
5790         /* Cannot run until previous stop completes properly */
5791         if (mddev->sysfs_active)
5792                 return -EBUSY;
5793
5794         /*
5795          * Analyze all RAID superblock(s)
5796          */
5797         if (!mddev->raid_disks) {
5798                 if (!mddev->persistent)
5799                         return -EINVAL;
5800                 err = analyze_sbs(mddev);
5801                 if (err)
5802                         return -EINVAL;
5803         }
5804
5805         if (mddev->level != LEVEL_NONE)
5806                 request_module("md-level-%d", mddev->level);
5807         else if (mddev->clevel[0])
5808                 request_module("md-%s", mddev->clevel);
5809
5810         /*
5811          * Drop all container device buffers, from now on
5812          * the only valid external interface is through the md
5813          * device.
5814          */
5815         mddev->has_superblocks = false;
5816         rdev_for_each(rdev, mddev) {
5817                 if (test_bit(Faulty, &rdev->flags))
5818                         continue;
5819                 sync_blockdev(rdev->bdev);
5820                 invalidate_bdev(rdev->bdev);
5821                 if (mddev->ro != 1 && rdev_read_only(rdev)) {
5822                         mddev->ro = 1;
5823                         if (mddev->gendisk)
5824                                 set_disk_ro(mddev->gendisk, 1);
5825                 }
5826
5827                 if (rdev->sb_page)
5828                         mddev->has_superblocks = true;
5829
5830                 /* perform some consistency tests on the device.
5831                  * We don't want the data to overlap the metadata,
5832                  * Internal Bitmap issues have been handled elsewhere.
5833                  */
5834                 if (rdev->meta_bdev) {
5835                         /* Nothing to check */;
5836                 } else if (rdev->data_offset < rdev->sb_start) {
5837                         if (mddev->dev_sectors &&
5838                             rdev->data_offset + mddev->dev_sectors
5839                             > rdev->sb_start) {
5840                                 pr_warn("md: %s: data overlaps metadata\n",
5841                                         mdname(mddev));
5842                                 return -EINVAL;
5843                         }
5844                 } else {
5845                         if (rdev->sb_start + rdev->sb_size/512
5846                             > rdev->data_offset) {
5847                                 pr_warn("md: %s: metadata overlaps data\n",
5848                                         mdname(mddev));
5849                                 return -EINVAL;
5850                         }
5851                 }
5852                 sysfs_notify_dirent_safe(rdev->sysfs_state);
5853         }
5854
5855         if (!bioset_initialized(&mddev->bio_set)) {
5856                 err = bioset_init(&mddev->bio_set, BIO_POOL_SIZE, 0, BIOSET_NEED_BVECS);
5857                 if (err)
5858                         return err;
5859         }
5860         if (!bioset_initialized(&mddev->sync_set)) {
5861                 err = bioset_init(&mddev->sync_set, BIO_POOL_SIZE, 0, BIOSET_NEED_BVECS);
5862                 if (err)
5863                         goto exit_bio_set;
5864         }
5865         if (mddev->level != 1 && mddev->level != 10 &&
5866             !bioset_initialized(&mddev->io_acct_set)) {
5867                 err = bioset_init(&mddev->io_acct_set, BIO_POOL_SIZE,
5868                                   offsetof(struct md_io_acct, bio_clone), 0);
5869                 if (err)
5870                         goto exit_sync_set;
5871         }
5872
5873         spin_lock(&pers_lock);
5874         pers = find_pers(mddev->level, mddev->clevel);
5875         if (!pers || !try_module_get(pers->owner)) {
5876                 spin_unlock(&pers_lock);
5877                 if (mddev->level != LEVEL_NONE)
5878                         pr_warn("md: personality for level %d is not loaded!\n",
5879                                 mddev->level);
5880                 else
5881                         pr_warn("md: personality for level %s is not loaded!\n",
5882                                 mddev->clevel);
5883                 err = -EINVAL;
5884                 goto abort;
5885         }
5886         spin_unlock(&pers_lock);
5887         if (mddev->level != pers->level) {
5888                 mddev->level = pers->level;
5889                 mddev->new_level = pers->level;
5890         }
5891         strlcpy(mddev->clevel, pers->name, sizeof(mddev->clevel));
5892
5893         if (mddev->reshape_position != MaxSector &&
5894             pers->start_reshape == NULL) {
5895                 /* This personality cannot handle reshaping... */
5896                 module_put(pers->owner);
5897                 err = -EINVAL;
5898                 goto abort;
5899         }
5900
5901         if (pers->sync_request) {
5902                 /* Warn if this is a potentially silly
5903                  * configuration.
5904                  */
5905                 char b[BDEVNAME_SIZE], b2[BDEVNAME_SIZE];
5906                 struct md_rdev *rdev2;
5907                 int warned = 0;
5908
5909                 rdev_for_each(rdev, mddev)
5910                         rdev_for_each(rdev2, mddev) {
5911                                 if (rdev < rdev2 &&
5912                                     rdev->bdev->bd_disk ==
5913                                     rdev2->bdev->bd_disk) {
5914                                         pr_warn("%s: WARNING: %s appears to be on the same physical disk as %s.\n",
5915                                                 mdname(mddev),
5916                                                 bdevname(rdev->bdev,b),
5917                                                 bdevname(rdev2->bdev,b2));
5918                                         warned = 1;
5919                                 }
5920                         }
5921
5922                 if (warned)
5923                         pr_warn("True protection against single-disk failure might be compromised.\n");
5924         }
5925
5926         mddev->recovery = 0;
5927         /* may be over-ridden by personality */
5928         mddev->resync_max_sectors = mddev->dev_sectors;
5929
5930         mddev->ok_start_degraded = start_dirty_degraded;
5931
5932         if (start_readonly && mddev->ro == 0)
5933                 mddev->ro = 2; /* read-only, but switch on first write */
5934
5935         err = pers->run(mddev);
5936         if (err)
5937                 pr_warn("md: pers->run() failed ...\n");
5938         else if (pers->size(mddev, 0, 0) < mddev->array_sectors) {
5939                 WARN_ONCE(!mddev->external_size,
5940                           "%s: default size too small, but 'external_size' not in effect?\n",
5941                           __func__);
5942                 pr_warn("md: invalid array_size %llu > default size %llu\n",
5943                         (unsigned long long)mddev->array_sectors / 2,
5944                         (unsigned long long)pers->size(mddev, 0, 0) / 2);
5945                 err = -EINVAL;
5946         }
5947         if (err == 0 && pers->sync_request &&
5948             (mddev->bitmap_info.file || mddev->bitmap_info.offset)) {
5949                 struct bitmap *bitmap;
5950
5951                 bitmap = md_bitmap_create(mddev, -1);
5952                 if (IS_ERR(bitmap)) {
5953                         err = PTR_ERR(bitmap);
5954                         pr_warn("%s: failed to create bitmap (%d)\n",
5955                                 mdname(mddev), err);
5956                 } else
5957                         mddev->bitmap = bitmap;
5958
5959         }
5960         if (err)
5961                 goto bitmap_abort;
5962
5963         if (mddev->bitmap_info.max_write_behind > 0) {
5964                 bool create_pool = false;
5965
5966                 rdev_for_each(rdev, mddev) {
5967                         if (test_bit(WriteMostly, &rdev->flags) &&
5968                             rdev_init_serial(rdev))
5969                                 create_pool = true;
5970                 }
5971                 if (create_pool && mddev->serial_info_pool == NULL) {
5972                         mddev->serial_info_pool =
5973                                 mempool_create_kmalloc_pool(NR_SERIAL_INFOS,
5974                                                     sizeof(struct serial_info));
5975                         if (!mddev->serial_info_pool) {
5976                                 err = -ENOMEM;
5977                                 goto bitmap_abort;
5978                         }
5979                 }
5980         }
5981
5982         if (mddev->queue) {
5983                 bool nonrot = true;
5984
5985                 rdev_for_each(rdev, mddev) {
5986                         if (rdev->raid_disk >= 0 &&
5987                             !blk_queue_nonrot(bdev_get_queue(rdev->bdev))) {
5988                                 nonrot = false;
5989                                 break;
5990                         }
5991                 }
5992                 if (mddev->degraded)
5993                         nonrot = false;
5994                 if (nonrot)
5995                         blk_queue_flag_set(QUEUE_FLAG_NONROT, mddev->queue);
5996                 else
5997                         blk_queue_flag_clear(QUEUE_FLAG_NONROT, mddev->queue);
5998                 blk_queue_flag_set(QUEUE_FLAG_IO_STAT, mddev->queue);
5999         }
6000         if (pers->sync_request) {
6001                 if (mddev->kobj.sd &&
6002                     sysfs_create_group(&mddev->kobj, &md_redundancy_group))
6003                         pr_warn("md: cannot register extra attributes for %s\n",
6004                                 mdname(mddev));
6005                 mddev->sysfs_action = sysfs_get_dirent_safe(mddev->kobj.sd, "sync_action");
6006                 mddev->sysfs_completed = sysfs_get_dirent_safe(mddev->kobj.sd, "sync_completed");
6007                 mddev->sysfs_degraded = sysfs_get_dirent_safe(mddev->kobj.sd, "degraded");
6008         } else if (mddev->ro == 2) /* auto-readonly not meaningful */
6009                 mddev->ro = 0;
6010
6011         atomic_set(&mddev->max_corr_read_errors,
6012                    MD_DEFAULT_MAX_CORRECTED_READ_ERRORS);
6013         mddev->safemode = 0;
6014         if (mddev_is_clustered(mddev))
6015                 mddev->safemode_delay = 0;
6016         else
6017                 mddev->safemode_delay = DEFAULT_SAFEMODE_DELAY;
6018         mddev->in_sync = 1;
6019         smp_wmb();
6020         spin_lock(&mddev->lock);
6021         mddev->pers = pers;
6022         spin_unlock(&mddev->lock);
6023         rdev_for_each(rdev, mddev)
6024                 if (rdev->raid_disk >= 0)
6025                         sysfs_link_rdev(mddev, rdev); /* failure here is OK */
6026
6027         if (mddev->degraded && !mddev->ro)
6028                 /* This ensures that recovering status is reported immediately
6029                  * via sysfs - until a lack of spares is confirmed.
6030                  */
6031                 set_bit(MD_RECOVERY_RECOVER, &mddev->recovery);
6032         set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
6033
6034         if (mddev->sb_flags)
6035                 md_update_sb(mddev, 0);
6036
6037         md_new_event(mddev);
6038         return 0;
6039
6040 bitmap_abort:
6041         mddev_detach(mddev);
6042         if (mddev->private)
6043                 pers->free(mddev, mddev->private);
6044         mddev->private = NULL;
6045         module_put(pers->owner);
6046         md_bitmap_destroy(mddev);
6047 abort:
6048         if (mddev->level != 1 && mddev->level != 10)
6049                 bioset_exit(&mddev->io_acct_set);
6050 exit_sync_set:
6051         bioset_exit(&mddev->sync_set);
6052 exit_bio_set:
6053         bioset_exit(&mddev->bio_set);
6054         return err;
6055 }
6056 EXPORT_SYMBOL_GPL(md_run);
6057
6058 int do_md_run(struct mddev *mddev)
6059 {
6060         int err;
6061
6062         set_bit(MD_NOT_READY, &mddev->flags);
6063         err = md_run(mddev);
6064         if (err)
6065                 goto out;
6066         err = md_bitmap_load(mddev);
6067         if (err) {
6068                 md_bitmap_destroy(mddev);
6069                 goto out;
6070         }
6071
6072         if (mddev_is_clustered(mddev))
6073                 md_allow_write(mddev);
6074
6075         /* run start up tasks that require md_thread */
6076         md_start(mddev);
6077
6078         md_wakeup_thread(mddev->thread);
6079         md_wakeup_thread(mddev->sync_thread); /* possibly kick off a reshape */
6080
6081         set_capacity_and_notify(mddev->gendisk, mddev->array_sectors);
6082         clear_bit(MD_NOT_READY, &mddev->flags);
6083         mddev->changed = 1;
6084         kobject_uevent(&disk_to_dev(mddev->gendisk)->kobj, KOBJ_CHANGE);
6085         sysfs_notify_dirent_safe(mddev->sysfs_state);
6086         sysfs_notify_dirent_safe(mddev->sysfs_action);
6087         sysfs_notify_dirent_safe(mddev->sysfs_degraded);
6088 out:
6089         clear_bit(MD_NOT_READY, &mddev->flags);
6090         return err;
6091 }
6092
6093 int md_start(struct mddev *mddev)
6094 {
6095         int ret = 0;
6096
6097         if (mddev->pers->start) {
6098                 set_bit(MD_RECOVERY_WAIT, &mddev->recovery);
6099                 md_wakeup_thread(mddev->thread);
6100                 ret = mddev->pers->start(mddev);
6101                 clear_bit(MD_RECOVERY_WAIT, &mddev->recovery);
6102                 md_wakeup_thread(mddev->sync_thread);
6103         }
6104         return ret;
6105 }
6106 EXPORT_SYMBOL_GPL(md_start);
6107
6108 static int restart_array(struct mddev *mddev)
6109 {
6110         struct gendisk *disk = mddev->gendisk;
6111         struct md_rdev *rdev;
6112         bool has_journal = false;
6113         bool has_readonly = false;
6114
6115         /* Complain if it has no devices */
6116         if (list_empty(&mddev->disks))
6117                 return -ENXIO;
6118         if (!mddev->pers)
6119                 return -EINVAL;
6120         if (!mddev->ro)
6121                 return -EBUSY;
6122
6123         rcu_read_lock();
6124         rdev_for_each_rcu(rdev, mddev) {
6125                 if (test_bit(Journal, &rdev->flags) &&
6126                     !test_bit(Faulty, &rdev->flags))
6127                         has_journal = true;
6128                 if (rdev_read_only(rdev))
6129                         has_readonly = true;
6130         }
6131         rcu_read_unlock();
6132         if (test_bit(MD_HAS_JOURNAL, &mddev->flags) && !has_journal)
6133                 /* Don't restart rw with journal missing/faulty */
6134                         return -EINVAL;
6135         if (has_readonly)
6136                 return -EROFS;
6137
6138         mddev->safemode = 0;
6139         mddev->ro = 0;
6140         set_disk_ro(disk, 0);
6141         pr_debug("md: %s switched to read-write mode.\n", mdname(mddev));
6142         /* Kick recovery or resync if necessary */
6143         set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
6144         md_wakeup_thread(mddev->thread);
6145         md_wakeup_thread(mddev->sync_thread);
6146         sysfs_notify_dirent_safe(mddev->sysfs_state);
6147         return 0;
6148 }
6149
6150 static void md_clean(struct mddev *mddev)
6151 {
6152         mddev->array_sectors = 0;
6153         mddev->external_size = 0;
6154         mddev->dev_sectors = 0;
6155         mddev->raid_disks = 0;
6156         mddev->recovery_cp = 0;
6157         mddev->resync_min = 0;
6158         mddev->resync_max = MaxSector;
6159         mddev->reshape_position = MaxSector;
6160         mddev->external = 0;
6161         mddev->persistent = 0;
6162         mddev->level = LEVEL_NONE;
6163         mddev->clevel[0] = 0;
6164         mddev->flags = 0;
6165         mddev->sb_flags = 0;
6166         mddev->ro = 0;
6167         mddev->metadata_type[0] = 0;
6168         mddev->chunk_sectors = 0;
6169         mddev->ctime = mddev->utime = 0;
6170         mddev->layout = 0;
6171         mddev->max_disks = 0;
6172         mddev->events = 0;
6173         mddev->can_decrease_events = 0;
6174         mddev->delta_disks = 0;
6175         mddev->reshape_backwards = 0;
6176         mddev->new_level = LEVEL_NONE;
6177         mddev->new_layout = 0;
6178         mddev->new_chunk_sectors = 0;
6179         mddev->curr_resync = 0;
6180         atomic64_set(&mddev->resync_mismatches, 0);
6181         mddev->suspend_lo = mddev->suspend_hi = 0;
6182         mddev->sync_speed_min = mddev->sync_speed_max = 0;
6183         mddev->recovery = 0;
6184         mddev->in_sync = 0;
6185         mddev->changed = 0;
6186         mddev->degraded = 0;
6187         mddev->safemode = 0;
6188         mddev->private = NULL;
6189         mddev->cluster_info = NULL;
6190         mddev->bitmap_info.offset = 0;
6191         mddev->bitmap_info.default_offset = 0;
6192         mddev->bitmap_info.default_space = 0;
6193         mddev->bitmap_info.chunksize = 0;
6194         mddev->bitmap_info.daemon_sleep = 0;
6195         mddev->bitmap_info.max_write_behind = 0;
6196         mddev->bitmap_info.nodes = 0;
6197 }
6198
6199 static void __md_stop_writes(struct mddev *mddev)
6200 {
6201         set_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
6202         if (work_pending(&mddev->del_work))
6203                 flush_workqueue(md_misc_wq);
6204         if (mddev->sync_thread) {
6205                 set_bit(MD_RECOVERY_INTR, &mddev->recovery);
6206                 md_reap_sync_thread(mddev);
6207         }
6208
6209         del_timer_sync(&mddev->safemode_timer);
6210
6211         if (mddev->pers && mddev->pers->quiesce) {
6212                 mddev->pers->quiesce(mddev, 1);
6213                 mddev->pers->quiesce(mddev, 0);
6214         }
6215         md_bitmap_flush(mddev);
6216
6217         if (mddev->ro == 0 &&
6218             ((!mddev->in_sync && !mddev_is_clustered(mddev)) ||
6219              mddev->sb_flags)) {
6220                 /* mark array as shutdown cleanly */
6221                 if (!mddev_is_clustered(mddev))
6222                         mddev->in_sync = 1;
6223                 md_update_sb(mddev, 1);
6224         }
6225         /* disable policy to guarantee rdevs free resources for serialization */
6226         mddev->serialize_policy = 0;
6227         mddev_destroy_serial_pool(mddev, NULL, true);
6228 }
6229
6230 void md_stop_writes(struct mddev *mddev)
6231 {
6232         mddev_lock_nointr(mddev);
6233         __md_stop_writes(mddev);
6234         mddev_unlock(mddev);
6235 }
6236 EXPORT_SYMBOL_GPL(md_stop_writes);
6237
6238 static void mddev_detach(struct mddev *mddev)
6239 {
6240         md_bitmap_wait_behind_writes(mddev);
6241         if (mddev->pers && mddev->pers->quiesce && !mddev->suspended) {
6242                 mddev->pers->quiesce(mddev, 1);
6243                 mddev->pers->quiesce(mddev, 0);
6244         }
6245         md_unregister_thread(&mddev->thread);
6246         if (mddev->queue)
6247                 blk_sync_queue(mddev->queue); /* the unplug fn references 'conf'*/
6248 }
6249
6250 static void __md_stop(struct mddev *mddev)
6251 {
6252         struct md_personality *pers = mddev->pers;
6253         md_bitmap_destroy(mddev);
6254         mddev_detach(mddev);
6255         /* Ensure ->event_work is done */
6256         if (mddev->event_work.func)
6257                 flush_workqueue(md_misc_wq);
6258         spin_lock(&mddev->lock);
6259         mddev->pers = NULL;
6260         spin_unlock(&mddev->lock);
6261         pers->free(mddev, mddev->private);
6262         mddev->private = NULL;
6263         if (pers->sync_request && mddev->to_remove == NULL)
6264                 mddev->to_remove = &md_redundancy_group;
6265         module_put(pers->owner);
6266         clear_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
6267 }
6268
6269 void md_stop(struct mddev *mddev)
6270 {
6271         /* stop the array and free an attached data structures.
6272          * This is called from dm-raid
6273          */
6274         __md_stop(mddev);
6275         bioset_exit(&mddev->bio_set);
6276         bioset_exit(&mddev->sync_set);
6277         if (mddev->level != 1 && mddev->level != 10)
6278                 bioset_exit(&mddev->io_acct_set);
6279 }
6280
6281 EXPORT_SYMBOL_GPL(md_stop);
6282
6283 static int md_set_readonly(struct mddev *mddev, struct block_device *bdev)
6284 {
6285         int err = 0;
6286         int did_freeze = 0;
6287
6288         if (!test_bit(MD_RECOVERY_FROZEN, &mddev->recovery)) {
6289                 did_freeze = 1;
6290                 set_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
6291                 md_wakeup_thread(mddev->thread);
6292         }
6293         if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery))
6294                 set_bit(MD_RECOVERY_INTR, &mddev->recovery);
6295         if (mddev->sync_thread)
6296                 /* Thread might be blocked waiting for metadata update
6297                  * which will now never happen */
6298                 wake_up_process(mddev->sync_thread->tsk);
6299
6300         if (mddev->external && test_bit(MD_SB_CHANGE_PENDING, &mddev->sb_flags))
6301                 return -EBUSY;
6302         mddev_unlock(mddev);
6303         wait_event(resync_wait, !test_bit(MD_RECOVERY_RUNNING,
6304                                           &mddev->recovery));
6305         wait_event(mddev->sb_wait,
6306                    !test_bit(MD_SB_CHANGE_PENDING, &mddev->sb_flags));
6307         mddev_lock_nointr(mddev);
6308
6309         mutex_lock(&mddev->open_mutex);
6310         if ((mddev->pers && atomic_read(&mddev->openers) > !!bdev) ||
6311             mddev->sync_thread ||
6312             test_bit(MD_RECOVERY_RUNNING, &mddev->recovery)) {
6313                 pr_warn("md: %s still in use.\n",mdname(mddev));
6314                 if (did_freeze) {
6315                         clear_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
6316                         set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
6317                         md_wakeup_thread(mddev->thread);
6318                 }
6319                 err = -EBUSY;
6320                 goto out;
6321         }
6322         if (mddev->pers) {
6323                 __md_stop_writes(mddev);
6324
6325                 err  = -ENXIO;
6326                 if (mddev->ro==1)
6327                         goto out;
6328                 mddev->ro = 1;
6329                 set_disk_ro(mddev->gendisk, 1);
6330                 clear_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
6331                 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
6332                 md_wakeup_thread(mddev->thread);
6333                 sysfs_notify_dirent_safe(mddev->sysfs_state);
6334                 err = 0;
6335         }
6336 out:
6337         mutex_unlock(&mddev->open_mutex);
6338         return err;
6339 }
6340
6341 /* mode:
6342  *   0 - completely stop and dis-assemble array
6343  *   2 - stop but do not disassemble array
6344  */
6345 static int do_md_stop(struct mddev *mddev, int mode,
6346                       struct block_device *bdev)
6347 {
6348         struct gendisk *disk = mddev->gendisk;
6349         struct md_rdev *rdev;
6350         int did_freeze = 0;
6351
6352         if (!test_bit(MD_RECOVERY_FROZEN, &mddev->recovery)) {
6353                 did_freeze = 1;
6354                 set_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
6355                 md_wakeup_thread(mddev->thread);
6356         }
6357         if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery))
6358                 set_bit(MD_RECOVERY_INTR, &mddev->recovery);
6359         if (mddev->sync_thread)
6360                 /* Thread might be blocked waiting for metadata update
6361                  * which will now never happen */
6362                 wake_up_process(mddev->sync_thread->tsk);
6363
6364         mddev_unlock(mddev);
6365         wait_event(resync_wait, (mddev->sync_thread == NULL &&
6366                                  !test_bit(MD_RECOVERY_RUNNING,
6367                                            &mddev->recovery)));
6368         mddev_lock_nointr(mddev);
6369
6370         mutex_lock(&mddev->open_mutex);
6371         if ((mddev->pers && atomic_read(&mddev->openers) > !!bdev) ||
6372             mddev->sysfs_active ||
6373             mddev->sync_thread ||
6374             test_bit(MD_RECOVERY_RUNNING, &mddev->recovery)) {
6375                 pr_warn("md: %s still in use.\n",mdname(mddev));
6376                 mutex_unlock(&mddev->open_mutex);
6377                 if (did_freeze) {
6378                         clear_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
6379                         set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
6380                         md_wakeup_thread(mddev->thread);
6381                 }
6382                 return -EBUSY;
6383         }
6384         if (mddev->pers) {
6385                 if (mddev->ro)
6386                         set_disk_ro(disk, 0);
6387
6388                 __md_stop_writes(mddev);
6389                 __md_stop(mddev);
6390
6391                 /* tell userspace to handle 'inactive' */
6392                 sysfs_notify_dirent_safe(mddev->sysfs_state);
6393
6394                 rdev_for_each(rdev, mddev)
6395                         if (rdev->raid_disk >= 0)
6396                                 sysfs_unlink_rdev(mddev, rdev);
6397
6398                 set_capacity_and_notify(disk, 0);
6399                 mutex_unlock(&mddev->open_mutex);
6400                 mddev->changed = 1;
6401
6402                 if (mddev->ro)
6403                         mddev->ro = 0;
6404         } else
6405                 mutex_unlock(&mddev->open_mutex);
6406         /*
6407          * Free resources if final stop
6408          */
6409         if (mode == 0) {
6410                 pr_info("md: %s stopped.\n", mdname(mddev));
6411
6412                 if (mddev->bitmap_info.file) {
6413                         struct file *f = mddev->bitmap_info.file;
6414                         spin_lock(&mddev->lock);
6415                         mddev->bitmap_info.file = NULL;
6416                         spin_unlock(&mddev->lock);
6417                         fput(f);
6418                 }
6419                 mddev->bitmap_info.offset = 0;
6420
6421                 export_array(mddev);
6422
6423                 md_clean(mddev);
6424                 if (mddev->hold_active == UNTIL_STOP)
6425                         mddev->hold_active = 0;
6426         }
6427         md_new_event(mddev);
6428         sysfs_notify_dirent_safe(mddev->sysfs_state);
6429         return 0;
6430 }
6431
6432 #ifndef MODULE
6433 static void autorun_array(struct mddev *mddev)
6434 {
6435         struct md_rdev *rdev;
6436         int err;
6437
6438         if (list_empty(&mddev->disks))
6439                 return;
6440
6441         pr_info("md: running: ");
6442
6443         rdev_for_each(rdev, mddev) {
6444                 char b[BDEVNAME_SIZE];
6445                 pr_cont("<%s>", bdevname(rdev->bdev,b));
6446         }
6447         pr_cont("\n");
6448
6449         err = do_md_run(mddev);
6450         if (err) {
6451                 pr_warn("md: do_md_run() returned %d\n", err);
6452                 do_md_stop(mddev, 0, NULL);
6453         }
6454 }
6455
6456 /*
6457  * lets try to run arrays based on all disks that have arrived
6458  * until now. (those are in pending_raid_disks)
6459  *
6460  * the method: pick the first pending disk, collect all disks with
6461  * the same UUID, remove all from the pending list and put them into
6462  * the 'same_array' list. Then order this list based on superblock
6463  * update time (freshest comes first), kick out 'old' disks and
6464  * compare superblocks. If everything's fine then run it.
6465  *
6466  * If "unit" is allocated, then bump its reference count
6467  */
6468 static void autorun_devices(int part)
6469 {
6470         struct md_rdev *rdev0, *rdev, *tmp;
6471         struct mddev *mddev;
6472         char b[BDEVNAME_SIZE];
6473
6474         pr_info("md: autorun ...\n");
6475         while (!list_empty(&pending_raid_disks)) {
6476                 int unit;
6477                 dev_t dev;
6478                 LIST_HEAD(candidates);
6479                 rdev0 = list_entry(pending_raid_disks.next,
6480                                          struct md_rdev, same_set);
6481
6482                 pr_debug("md: considering %s ...\n", bdevname(rdev0->bdev,b));
6483                 INIT_LIST_HEAD(&candidates);
6484                 rdev_for_each_list(rdev, tmp, &pending_raid_disks)
6485                         if (super_90_load(rdev, rdev0, 0) >= 0) {
6486                                 pr_debug("md:  adding %s ...\n",
6487                                          bdevname(rdev->bdev,b));
6488                                 list_move(&rdev->same_set, &candidates);
6489                         }
6490                 /*
6491                  * now we have a set of devices, with all of them having
6492                  * mostly sane superblocks. It's time to allocate the
6493                  * mddev.
6494                  */
6495                 if (part) {
6496                         dev = MKDEV(mdp_major,
6497                                     rdev0->preferred_minor << MdpMinorShift);
6498                         unit = MINOR(dev) >> MdpMinorShift;
6499                 } else {
6500                         dev = MKDEV(MD_MAJOR, rdev0->preferred_minor);
6501                         unit = MINOR(dev);
6502                 }
6503                 if (rdev0->preferred_minor != unit) {
6504                         pr_warn("md: unit number in %s is bad: %d\n",
6505                                 bdevname(rdev0->bdev, b), rdev0->preferred_minor);
6506                         break;
6507                 }
6508
6509                 md_probe(dev);
6510                 mddev = mddev_find(dev);
6511                 if (!mddev)
6512                         break;
6513
6514                 if (mddev_lock(mddev))
6515                         pr_warn("md: %s locked, cannot run\n", mdname(mddev));
6516                 else if (mddev->raid_disks || mddev->major_version
6517                          || !list_empty(&mddev->disks)) {
6518                         pr_warn("md: %s already running, cannot run %s\n",
6519                                 mdname(mddev), bdevname(rdev0->bdev,b));
6520                         mddev_unlock(mddev);
6521                 } else {
6522                         pr_debug("md: created %s\n", mdname(mddev));
6523                         mddev->persistent = 1;
6524                         rdev_for_each_list(rdev, tmp, &candidates) {
6525                                 list_del_init(&rdev->same_set);
6526                                 if (bind_rdev_to_array(rdev, mddev))
6527                                         export_rdev(rdev);
6528                         }
6529                         autorun_array(mddev);
6530                         mddev_unlock(mddev);
6531                 }
6532                 /* on success, candidates will be empty, on error
6533                  * it won't...
6534                  */
6535                 rdev_for_each_list(rdev, tmp, &candidates) {
6536                         list_del_init(&rdev->same_set);
6537                         export_rdev(rdev);
6538                 }
6539                 mddev_put(mddev);
6540         }
6541         pr_info("md: ... autorun DONE.\n");
6542 }
6543 #endif /* !MODULE */
6544
6545 static int get_version(void __user *arg)
6546 {
6547         mdu_version_t ver;
6548
6549         ver.major = MD_MAJOR_VERSION;
6550         ver.minor = MD_MINOR_VERSION;
6551         ver.patchlevel = MD_PATCHLEVEL_VERSION;
6552
6553         if (copy_to_user(arg, &ver, sizeof(ver)))
6554                 return -EFAULT;
6555
6556         return 0;
6557 }
6558
6559 static int get_array_info(struct mddev *mddev, void __user *arg)
6560 {
6561         mdu_array_info_t info;
6562         int nr,working,insync,failed,spare;
6563         struct md_rdev *rdev;
6564
6565         nr = working = insync = failed = spare = 0;
6566         rcu_read_lock();
6567         rdev_for_each_rcu(rdev, mddev) {
6568                 nr++;
6569                 if (test_bit(Faulty, &rdev->flags))
6570                         failed++;
6571                 else {
6572                         working++;
6573                         if (test_bit(In_sync, &rdev->flags))
6574                                 insync++;
6575                         else if (test_bit(Journal, &rdev->flags))
6576                                 /* TODO: add journal count to md_u.h */
6577                                 ;
6578                         else
6579                                 spare++;
6580                 }
6581         }
6582         rcu_read_unlock();
6583
6584         info.major_version = mddev->major_version;
6585         info.minor_version = mddev->minor_version;
6586         info.patch_version = MD_PATCHLEVEL_VERSION;
6587         info.ctime         = clamp_t(time64_t, mddev->ctime, 0, U32_MAX);
6588         info.level         = mddev->level;
6589         info.size          = mddev->dev_sectors / 2;
6590         if (info.size != mddev->dev_sectors / 2) /* overflow */
6591                 info.size = -1;
6592         info.nr_disks      = nr;
6593         info.raid_disks    = mddev->raid_disks;
6594         info.md_minor      = mddev->md_minor;
6595         info.not_persistent= !mddev->persistent;
6596
6597         info.utime         = clamp_t(time64_t, mddev->utime, 0, U32_MAX);
6598         info.state         = 0;
6599         if (mddev->in_sync)
6600                 info.state = (1<<MD_SB_CLEAN);
6601         if (mddev->bitmap && mddev->bitmap_info.offset)
6602                 info.state |= (1<<MD_SB_BITMAP_PRESENT);
6603         if (mddev_is_clustered(mddev))
6604                 info.state |= (1<<MD_SB_CLUSTERED);
6605         info.active_disks  = insync;
6606         info.working_disks = working;
6607         info.failed_disks  = failed;
6608         info.spare_disks   = spare;
6609
6610         info.layout        = mddev->layout;
6611         info.chunk_size    = mddev->chunk_sectors << 9;
6612
6613         if (copy_to_user(arg, &info, sizeof(info)))
6614                 return -EFAULT;
6615
6616         return 0;
6617 }
6618
6619 static int get_bitmap_file(struct mddev *mddev, void __user * arg)
6620 {
6621         mdu_bitmap_file_t *file = NULL; /* too big for stack allocation */
6622         char *ptr;
6623         int err;
6624
6625         file = kzalloc(sizeof(*file), GFP_NOIO);
6626         if (!file)
6627                 return -ENOMEM;
6628
6629         err = 0;
6630         spin_lock(&mddev->lock);
6631         /* bitmap enabled */
6632         if (mddev->bitmap_info.file) {
6633                 ptr = file_path(mddev->bitmap_info.file, file->pathname,
6634                                 sizeof(file->pathname));
6635                 if (IS_ERR(ptr))
6636                         err = PTR_ERR(ptr);
6637                 else
6638                         memmove(file->pathname, ptr,
6639                                 sizeof(file->pathname)-(ptr-file->pathname));
6640         }
6641         spin_unlock(&mddev->lock);
6642
6643         if (err == 0 &&
6644             copy_to_user(arg, file, sizeof(*file)))
6645                 err = -EFAULT;
6646
6647         kfree(file);
6648         return err;
6649 }
6650
6651 static int get_disk_info(struct mddev *mddev, void __user * arg)
6652 {
6653         mdu_disk_info_t info;
6654         struct md_rdev *rdev;
6655
6656         if (copy_from_user(&info, arg, sizeof(info)))
6657                 return -EFAULT;
6658
6659         rcu_read_lock();
6660         rdev = md_find_rdev_nr_rcu(mddev, info.number);
6661         if (rdev) {
6662                 info.major = MAJOR(rdev->bdev->bd_dev);
6663                 info.minor = MINOR(rdev->bdev->bd_dev);
6664                 info.raid_disk = rdev->raid_disk;
6665                 info.state = 0;
6666                 if (test_bit(Faulty, &rdev->flags))
6667                         info.state |= (1<<MD_DISK_FAULTY);
6668                 else if (test_bit(In_sync, &rdev->flags)) {
6669                         info.state |= (1<<MD_DISK_ACTIVE);
6670                         info.state |= (1<<MD_DISK_SYNC);
6671                 }
6672                 if (test_bit(Journal, &rdev->flags))
6673                         info.state |= (1<<MD_DISK_JOURNAL);
6674                 if (test_bit(WriteMostly, &rdev->flags))
6675                         info.state |= (1<<MD_DISK_WRITEMOSTLY);
6676                 if (test_bit(FailFast, &rdev->flags))
6677                         info.state |= (1<<MD_DISK_FAILFAST);
6678         } else {
6679                 info.major = info.minor = 0;
6680                 info.raid_disk = -1;
6681                 info.state = (1<<MD_DISK_REMOVED);
6682         }
6683         rcu_read_unlock();
6684
6685         if (copy_to_user(arg, &info, sizeof(info)))
6686                 return -EFAULT;
6687
6688         return 0;
6689 }
6690
6691 int md_add_new_disk(struct mddev *mddev, struct mdu_disk_info_s *info)
6692 {
6693         char b[BDEVNAME_SIZE], b2[BDEVNAME_SIZE];
6694         struct md_rdev *rdev;
6695         dev_t dev = MKDEV(info->major,info->minor);
6696
6697         if (mddev_is_clustered(mddev) &&
6698                 !(info->state & ((1 << MD_DISK_CLUSTER_ADD) | (1 << MD_DISK_CANDIDATE)))) {
6699                 pr_warn("%s: Cannot add to clustered mddev.\n",
6700                         mdname(mddev));
6701                 return -EINVAL;
6702         }
6703
6704         if (info->major != MAJOR(dev) || info->minor != MINOR(dev))
6705                 return -EOVERFLOW;
6706
6707         if (!mddev->raid_disks) {
6708                 int err;
6709                 /* expecting a device which has a superblock */
6710                 rdev = md_import_device(dev, mddev->major_version, mddev->minor_version);
6711                 if (IS_ERR(rdev)) {
6712                         pr_warn("md: md_import_device returned %ld\n",
6713                                 PTR_ERR(rdev));
6714                         return PTR_ERR(rdev);
6715                 }
6716                 if (!list_empty(&mddev->disks)) {
6717                         struct md_rdev *rdev0
6718                                 = list_entry(mddev->disks.next,
6719                                              struct md_rdev, same_set);
6720                         err = super_types[mddev->major_version]
6721                                 .load_super(rdev, rdev0, mddev->minor_version);
6722                         if (err < 0) {
6723                                 pr_warn("md: %s has different UUID to %s\n",
6724                                         bdevname(rdev->bdev,b),
6725                                         bdevname(rdev0->bdev,b2));
6726                                 export_rdev(rdev);
6727                                 return -EINVAL;
6728                         }
6729                 }
6730                 err = bind_rdev_to_array(rdev, mddev);
6731                 if (err)
6732                         export_rdev(rdev);
6733                 return err;
6734         }
6735
6736         /*
6737          * md_add_new_disk can be used once the array is assembled
6738          * to add "hot spares".  They must already have a superblock
6739          * written
6740          */
6741         if (mddev->pers) {
6742                 int err;
6743                 if (!mddev->pers->hot_add_disk) {
6744                         pr_warn("%s: personality does not support diskops!\n",
6745                                 mdname(mddev));
6746                         return -EINVAL;
6747                 }
6748                 if (mddev->persistent)
6749                         rdev = md_import_device(dev, mddev->major_version,
6750                                                 mddev->minor_version);
6751                 else
6752                         rdev = md_import_device(dev, -1, -1);
6753                 if (IS_ERR(rdev)) {
6754                         pr_warn("md: md_import_device returned %ld\n",
6755                                 PTR_ERR(rdev));
6756                         return PTR_ERR(rdev);
6757                 }
6758                 /* set saved_raid_disk if appropriate */
6759                 if (!mddev->persistent) {
6760                         if (info->state & (1<<MD_DISK_SYNC)  &&
6761                             info->raid_disk < mddev->raid_disks) {
6762                                 rdev->raid_disk = info->raid_disk;
6763                                 set_bit(In_sync, &rdev->flags);
6764                                 clear_bit(Bitmap_sync, &rdev->flags);
6765                         } else
6766                                 rdev->raid_disk = -1;
6767                         rdev->saved_raid_disk = rdev->raid_disk;
6768                 } else
6769                         super_types[mddev->major_version].
6770                                 validate_super(mddev, rdev);
6771                 if ((info->state & (1<<MD_DISK_SYNC)) &&
6772                      rdev->raid_disk != info->raid_disk) {
6773                         /* This was a hot-add request, but events doesn't
6774                          * match, so reject it.
6775                          */
6776                         export_rdev(rdev);
6777                         return -EINVAL;
6778                 }
6779
6780                 clear_bit(In_sync, &rdev->flags); /* just to be sure */
6781                 if (info->state & (1<<MD_DISK_WRITEMOSTLY))
6782                         set_bit(WriteMostly, &rdev->flags);
6783                 else
6784                         clear_bit(WriteMostly, &rdev->flags);
6785                 if (info->state & (1<<MD_DISK_FAILFAST))
6786                         set_bit(FailFast, &rdev->flags);
6787                 else
6788                         clear_bit(FailFast, &rdev->flags);
6789
6790                 if (info->state & (1<<MD_DISK_JOURNAL)) {
6791                         struct md_rdev *rdev2;
6792                         bool has_journal = false;
6793
6794                         /* make sure no existing journal disk */
6795                         rdev_for_each(rdev2, mddev) {
6796                                 if (test_bit(Journal, &rdev2->flags)) {
6797                                         has_journal = true;
6798                                         break;
6799                                 }
6800                         }
6801                         if (has_journal || mddev->bitmap) {
6802                                 export_rdev(rdev);
6803                                 return -EBUSY;
6804                         }
6805                         set_bit(Journal, &rdev->flags);
6806                 }
6807                 /*
6808                  * check whether the device shows up in other nodes
6809                  */
6810                 if (mddev_is_clustered(mddev)) {
6811                         if (info->state & (1 << MD_DISK_CANDIDATE))
6812                                 set_bit(Candidate, &rdev->flags);
6813                         else if (info->state & (1 << MD_DISK_CLUSTER_ADD)) {
6814                                 /* --add initiated by this node */
6815                                 err = md_cluster_ops->add_new_disk(mddev, rdev);
6816                                 if (err) {
6817                                         export_rdev(rdev);
6818                                         return err;
6819                                 }
6820                         }
6821                 }
6822
6823                 rdev->raid_disk = -1;
6824                 err = bind_rdev_to_array(rdev, mddev);
6825
6826                 if (err)
6827                         export_rdev(rdev);
6828
6829                 if (mddev_is_clustered(mddev)) {
6830                         if (info->state & (1 << MD_DISK_CANDIDATE)) {
6831                                 if (!err) {
6832                                         err = md_cluster_ops->new_disk_ack(mddev,
6833                                                 err == 0);
6834                                         if (err)
6835                                                 md_kick_rdev_from_array(rdev);
6836                                 }
6837                         } else {
6838                                 if (err)
6839                                         md_cluster_ops->add_new_disk_cancel(mddev);
6840                                 else
6841                                         err = add_bound_rdev(rdev);
6842                         }
6843
6844                 } else if (!err)
6845                         err = add_bound_rdev(rdev);
6846
6847                 return err;
6848         }
6849
6850         /* otherwise, md_add_new_disk is only allowed
6851          * for major_version==0 superblocks
6852          */
6853         if (mddev->major_version != 0) {
6854                 pr_warn("%s: ADD_NEW_DISK not supported\n", mdname(mddev));
6855                 return -EINVAL;
6856         }
6857
6858         if (!(info->state & (1<<MD_DISK_FAULTY))) {
6859                 int err;
6860                 rdev = md_import_device(dev, -1, 0);
6861                 if (IS_ERR(rdev)) {
6862                         pr_warn("md: error, md_import_device() returned %ld\n",
6863                                 PTR_ERR(rdev));
6864                         return PTR_ERR(rdev);
6865                 }
6866                 rdev->desc_nr = info->number;
6867                 if (info->raid_disk < mddev->raid_disks)
6868                         rdev->raid_disk = info->raid_disk;
6869                 else
6870                         rdev->raid_disk = -1;
6871
6872                 if (rdev->raid_disk < mddev->raid_disks)
6873                         if (info->state & (1<<MD_DISK_SYNC))
6874                                 set_bit(In_sync, &rdev->flags);
6875
6876                 if (info->state & (1<<MD_DISK_WRITEMOSTLY))
6877                         set_bit(WriteMostly, &rdev->flags);
6878                 if (info->state & (1<<MD_DISK_FAILFAST))
6879                         set_bit(FailFast, &rdev->flags);
6880
6881                 if (!mddev->persistent) {
6882                         pr_debug("md: nonpersistent superblock ...\n");
6883                         rdev->sb_start = i_size_read(rdev->bdev->bd_inode) / 512;
6884                 } else
6885                         rdev->sb_start = calc_dev_sboffset(rdev);
6886                 rdev->sectors = rdev->sb_start;
6887
6888                 err = bind_rdev_to_array(rdev, mddev);
6889                 if (err) {
6890                         export_rdev(rdev);
6891                         return err;
6892                 }
6893         }
6894
6895         return 0;
6896 }
6897
6898 static int hot_remove_disk(struct mddev *mddev, dev_t dev)
6899 {
6900         char b[BDEVNAME_SIZE];
6901         struct md_rdev *rdev;
6902
6903         if (!mddev->pers)
6904                 return -ENODEV;
6905
6906         rdev = find_rdev(mddev, dev);
6907         if (!rdev)
6908                 return -ENXIO;
6909
6910         if (rdev->raid_disk < 0)
6911                 goto kick_rdev;
6912
6913         clear_bit(Blocked, &rdev->flags);
6914         remove_and_add_spares(mddev, rdev);
6915
6916         if (rdev->raid_disk >= 0)
6917                 goto busy;
6918
6919 kick_rdev:
6920         if (mddev_is_clustered(mddev)) {
6921                 if (md_cluster_ops->remove_disk(mddev, rdev))
6922                         goto busy;
6923         }
6924
6925         md_kick_rdev_from_array(rdev);
6926         set_bit(MD_SB_CHANGE_DEVS, &mddev->sb_flags);
6927         if (mddev->thread)
6928                 md_wakeup_thread(mddev->thread);
6929         else
6930                 md_update_sb(mddev, 1);
6931         md_new_event(mddev);
6932
6933         return 0;
6934 busy:
6935         pr_debug("md: cannot remove active disk %s from %s ...\n",
6936                  bdevname(rdev->bdev,b), mdname(mddev));
6937         return -EBUSY;
6938 }
6939
6940 static int hot_add_disk(struct mddev *mddev, dev_t dev)
6941 {
6942         char b[BDEVNAME_SIZE];
6943         int err;
6944         struct md_rdev *rdev;
6945
6946         if (!mddev->pers)
6947                 return -ENODEV;
6948
6949         if (mddev->major_version != 0) {
6950                 pr_warn("%s: HOT_ADD may only be used with version-0 superblocks.\n",
6951                         mdname(mddev));
6952                 return -EINVAL;
6953         }
6954         if (!mddev->pers->hot_add_disk) {
6955                 pr_warn("%s: personality does not support diskops!\n",
6956                         mdname(mddev));
6957                 return -EINVAL;
6958         }
6959
6960         rdev = md_import_device(dev, -1, 0);
6961         if (IS_ERR(rdev)) {
6962                 pr_warn("md: error, md_import_device() returned %ld\n",
6963                         PTR_ERR(rdev));
6964                 return -EINVAL;
6965         }
6966
6967         if (mddev->persistent)
6968                 rdev->sb_start = calc_dev_sboffset(rdev);
6969         else
6970                 rdev->sb_start = i_size_read(rdev->bdev->bd_inode) / 512;
6971
6972         rdev->sectors = rdev->sb_start;
6973
6974         if (test_bit(Faulty, &rdev->flags)) {
6975                 pr_warn("md: can not hot-add faulty %s disk to %s!\n",
6976                         bdevname(rdev->bdev,b), mdname(mddev));
6977                 err = -EINVAL;
6978                 goto abort_export;
6979         }
6980
6981         clear_bit(In_sync, &rdev->flags);
6982         rdev->desc_nr = -1;
6983         rdev->saved_raid_disk = -1;
6984         err = bind_rdev_to_array(rdev, mddev);
6985         if (err)
6986                 goto abort_export;
6987
6988         /*
6989          * The rest should better be atomic, we can have disk failures
6990          * noticed in interrupt contexts ...
6991          */
6992
6993         rdev->raid_disk = -1;
6994
6995         set_bit(MD_SB_CHANGE_DEVS, &mddev->sb_flags);
6996         if (!mddev->thread)
6997                 md_update_sb(mddev, 1);
6998         /*
6999          * Kick recovery, maybe this spare has to be added to the
7000          * array immediately.
7001          */
7002         set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
7003         md_wakeup_thread(mddev->thread);
7004         md_new_event(mddev);
7005         return 0;
7006
7007 abort_export:
7008         export_rdev(rdev);
7009         return err;
7010 }
7011
7012 static int set_bitmap_file(struct mddev *mddev, int fd)
7013 {
7014         int err = 0;
7015
7016         if (mddev->pers) {
7017                 if (!mddev->pers->quiesce || !mddev->thread)
7018                         return -EBUSY;
7019                 if (mddev->recovery || mddev->sync_thread)
7020                         return -EBUSY;
7021                 /* we should be able to change the bitmap.. */
7022         }
7023
7024         if (fd >= 0) {
7025                 struct inode *inode;
7026                 struct file *f;
7027
7028                 if (mddev->bitmap || mddev->bitmap_info.file)
7029                         return -EEXIST; /* cannot add when bitmap is present */
7030                 f = fget(fd);
7031
7032                 if (f == NULL) {
7033                         pr_warn("%s: error: failed to get bitmap file\n",
7034                                 mdname(mddev));
7035                         return -EBADF;
7036                 }
7037
7038                 inode = f->f_mapping->host;
7039                 if (!S_ISREG(inode->i_mode)) {
7040                         pr_warn("%s: error: bitmap file must be a regular file\n",
7041                                 mdname(mddev));
7042                         err = -EBADF;
7043                 } else if (!(f->f_mode & FMODE_WRITE)) {
7044                         pr_warn("%s: error: bitmap file must open for write\n",
7045                                 mdname(mddev));
7046                         err = -EBADF;
7047                 } else if (atomic_read(&inode->i_writecount) != 1) {
7048                         pr_warn("%s: error: bitmap file is already in use\n",
7049                                 mdname(mddev));
7050                         err = -EBUSY;
7051                 }
7052                 if (err) {
7053                         fput(f);
7054                         return err;
7055                 }
7056                 mddev->bitmap_info.file = f;
7057                 mddev->bitmap_info.offset = 0; /* file overrides offset */
7058         } else if (mddev->bitmap == NULL)
7059                 return -ENOENT; /* cannot remove what isn't there */
7060         err = 0;
7061         if (mddev->pers) {
7062                 if (fd >= 0) {
7063                         struct bitmap *bitmap;
7064
7065                         bitmap = md_bitmap_create(mddev, -1);
7066                         mddev_suspend(mddev);
7067                         if (!IS_ERR(bitmap)) {
7068                                 mddev->bitmap = bitmap;
7069                                 err = md_bitmap_load(mddev);
7070                         } else
7071                                 err = PTR_ERR(bitmap);
7072                         if (err) {
7073                                 md_bitmap_destroy(mddev);
7074                                 fd = -1;
7075                         }
7076                         mddev_resume(mddev);
7077                 } else if (fd < 0) {
7078                         mddev_suspend(mddev);
7079                         md_bitmap_destroy(mddev);
7080                         mddev_resume(mddev);
7081                 }
7082         }
7083         if (fd < 0) {
7084                 struct file *f = mddev->bitmap_info.file;
7085                 if (f) {
7086                         spin_lock(&mddev->lock);
7087                         mddev->bitmap_info.file = NULL;
7088                         spin_unlock(&mddev->lock);
7089                         fput(f);
7090                 }
7091         }
7092
7093         return err;
7094 }
7095
7096 /*
7097  * md_set_array_info is used two different ways
7098  * The original usage is when creating a new array.
7099  * In this usage, raid_disks is > 0 and it together with
7100  *  level, size, not_persistent,layout,chunksize determine the
7101  *  shape of the array.
7102  *  This will always create an array with a type-0.90.0 superblock.
7103  * The newer usage is when assembling an array.
7104  *  In this case raid_disks will be 0, and the major_version field is
7105  *  use to determine which style super-blocks are to be found on the devices.
7106  *  The minor and patch _version numbers are also kept incase the
7107  *  super_block handler wishes to interpret them.
7108  */
7109 int md_set_array_info(struct mddev *mddev, struct mdu_array_info_s *info)
7110 {
7111         if (info->raid_disks == 0) {
7112                 /* just setting version number for superblock loading */
7113                 if (info->major_version < 0 ||
7114                     info->major_version >= ARRAY_SIZE(super_types) ||
7115                     super_types[info->major_version].name == NULL) {
7116                         /* maybe try to auto-load a module? */
7117                         pr_warn("md: superblock version %d not known\n",
7118                                 info->major_version);
7119                         return -EINVAL;
7120                 }
7121                 mddev->major_version = info->major_version;
7122                 mddev->minor_version = info->minor_version;
7123                 mddev->patch_version = info->patch_version;
7124                 mddev->persistent = !info->not_persistent;
7125                 /* ensure mddev_put doesn't delete this now that there
7126                  * is some minimal configuration.
7127                  */
7128                 mddev->ctime         = ktime_get_real_seconds();
7129                 return 0;
7130         }
7131         mddev->major_version = MD_MAJOR_VERSION;
7132         mddev->minor_version = MD_MINOR_VERSION;
7133         mddev->patch_version = MD_PATCHLEVEL_VERSION;
7134         mddev->ctime         = ktime_get_real_seconds();
7135
7136         mddev->level         = info->level;
7137         mddev->clevel[0]     = 0;
7138         mddev->dev_sectors   = 2 * (sector_t)info->size;
7139         mddev->raid_disks    = info->raid_disks;
7140         /* don't set md_minor, it is determined by which /dev/md* was
7141          * openned
7142          */
7143         if (info->state & (1<<MD_SB_CLEAN))
7144                 mddev->recovery_cp = MaxSector;
7145         else
7146                 mddev->recovery_cp = 0;
7147         mddev->persistent    = ! info->not_persistent;
7148         mddev->external      = 0;
7149
7150         mddev->layout        = info->layout;
7151         if (mddev->level == 0)
7152                 /* Cannot trust RAID0 layout info here */
7153                 mddev->layout = -1;
7154         mddev->chunk_sectors = info->chunk_size >> 9;
7155
7156         if (mddev->persistent) {
7157                 mddev->max_disks = MD_SB_DISKS;
7158                 mddev->flags = 0;
7159                 mddev->sb_flags = 0;
7160         }
7161         set_bit(MD_SB_CHANGE_DEVS, &mddev->sb_flags);
7162
7163         mddev->bitmap_info.default_offset = MD_SB_BYTES >> 9;
7164         mddev->bitmap_info.default_space = 64*2 - (MD_SB_BYTES >> 9);
7165         mddev->bitmap_info.offset = 0;
7166
7167         mddev->reshape_position = MaxSector;
7168
7169         /*
7170          * Generate a 128 bit UUID
7171          */
7172         get_random_bytes(mddev->uuid, 16);
7173
7174         mddev->new_level = mddev->level;
7175         mddev->new_chunk_sectors = mddev->chunk_sectors;
7176         mddev->new_layout = mddev->layout;
7177         mddev->delta_disks = 0;
7178         mddev->reshape_backwards = 0;
7179
7180         return 0;
7181 }
7182
7183 void md_set_array_sectors(struct mddev *mddev, sector_t array_sectors)
7184 {
7185         lockdep_assert_held(&mddev->reconfig_mutex);
7186
7187         if (mddev->external_size)
7188                 return;
7189
7190         mddev->array_sectors = array_sectors;
7191 }
7192 EXPORT_SYMBOL(md_set_array_sectors);
7193
7194 static int update_size(struct mddev *mddev, sector_t num_sectors)
7195 {
7196         struct md_rdev *rdev;
7197         int rv;
7198         int fit = (num_sectors == 0);
7199         sector_t old_dev_sectors = mddev->dev_sectors;
7200
7201         if (mddev->pers->resize == NULL)
7202                 return -EINVAL;
7203         /* The "num_sectors" is the number of sectors of each device that
7204          * is used.  This can only make sense for arrays with redundancy.
7205          * linear and raid0 always use whatever space is available. We can only
7206          * consider changing this number if no resync or reconstruction is
7207          * happening, and if the new size is acceptable. It must fit before the
7208          * sb_start or, if that is <data_offset, it must fit before the size
7209          * of each device.  If num_sectors is zero, we find the largest size
7210          * that fits.
7211          */
7212         if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery) ||
7213             mddev->sync_thread)
7214                 return -EBUSY;
7215         if (mddev->ro)
7216                 return -EROFS;
7217
7218         rdev_for_each(rdev, mddev) {
7219                 sector_t avail = rdev->sectors;
7220
7221                 if (fit && (num_sectors == 0 || num_sectors > avail))
7222                         num_sectors = avail;
7223                 if (avail < num_sectors)
7224                         return -ENOSPC;
7225         }
7226         rv = mddev->pers->resize(mddev, num_sectors);
7227         if (!rv) {
7228                 if (mddev_is_clustered(mddev))
7229                         md_cluster_ops->update_size(mddev, old_dev_sectors);
7230                 else if (mddev->queue) {
7231                         set_capacity_and_notify(mddev->gendisk,
7232                                                 mddev->array_sectors);
7233                 }
7234         }
7235         return rv;
7236 }
7237
7238 static int update_raid_disks(struct mddev *mddev, int raid_disks)
7239 {
7240         int rv;
7241         struct md_rdev *rdev;
7242         /* change the number of raid disks */
7243         if (mddev->pers->check_reshape == NULL)
7244                 return -EINVAL;
7245         if (mddev->ro)
7246                 return -EROFS;
7247         if (raid_disks <= 0 ||
7248             (mddev->max_disks && raid_disks >= mddev->max_disks))
7249                 return -EINVAL;
7250         if (mddev->sync_thread ||
7251             test_bit(MD_RECOVERY_RUNNING, &mddev->recovery) ||
7252             test_bit(MD_RESYNCING_REMOTE, &mddev->recovery) ||
7253             mddev->reshape_position != MaxSector)
7254                 return -EBUSY;
7255
7256         rdev_for_each(rdev, mddev) {
7257                 if (mddev->raid_disks < raid_disks &&
7258                     rdev->data_offset < rdev->new_data_offset)
7259                         return -EINVAL;
7260                 if (mddev->raid_disks > raid_disks &&
7261                     rdev->data_offset > rdev->new_data_offset)
7262                         return -EINVAL;
7263         }
7264
7265         mddev->delta_disks = raid_disks - mddev->raid_disks;
7266         if (mddev->delta_disks < 0)
7267                 mddev->reshape_backwards = 1;
7268         else if (mddev->delta_disks > 0)
7269                 mddev->reshape_backwards = 0;
7270
7271         rv = mddev->pers->check_reshape(mddev);
7272         if (rv < 0) {
7273                 mddev->delta_disks = 0;
7274                 mddev->reshape_backwards = 0;
7275         }
7276         return rv;
7277 }
7278
7279 /*
7280  * update_array_info is used to change the configuration of an
7281  * on-line array.
7282  * The version, ctime,level,size,raid_disks,not_persistent, layout,chunk_size
7283  * fields in the info are checked against the array.
7284  * Any differences that cannot be handled will cause an error.
7285  * Normally, only one change can be managed at a time.
7286  */
7287 static int update_array_info(struct mddev *mddev, mdu_array_info_t *info)
7288 {
7289         int rv = 0;
7290         int cnt = 0;
7291         int state = 0;
7292
7293         /* calculate expected state,ignoring low bits */
7294         if (mddev->bitmap && mddev->bitmap_info.offset)
7295                 state |= (1 << MD_SB_BITMAP_PRESENT);
7296
7297         if (mddev->major_version != info->major_version ||
7298             mddev->minor_version != info->minor_version ||
7299 /*          mddev->patch_version != info->patch_version || */
7300             mddev->ctime         != info->ctime         ||
7301             mddev->level         != info->level         ||
7302 /*          mddev->layout        != info->layout        || */
7303             mddev->persistent    != !info->not_persistent ||
7304             mddev->chunk_sectors != info->chunk_size >> 9 ||
7305             /* ignore bottom 8 bits of state, and allow SB_BITMAP_PRESENT to change */
7306             ((state^info->state) & 0xfffffe00)
7307                 )
7308                 return -EINVAL;
7309         /* Check there is only one change */
7310         if (info->size >= 0 && mddev->dev_sectors / 2 != info->size)
7311                 cnt++;
7312         if (mddev->raid_disks != info->raid_disks)
7313                 cnt++;
7314         if (mddev->layout != info->layout)
7315                 cnt++;
7316         if ((state ^ info->state) & (1<<MD_SB_BITMAP_PRESENT))
7317                 cnt++;
7318         if (cnt == 0)
7319                 return 0;
7320         if (cnt > 1)
7321                 return -EINVAL;
7322
7323         if (mddev->layout != info->layout) {
7324                 /* Change layout
7325                  * we don't need to do anything at the md level, the
7326                  * personality will take care of it all.
7327                  */
7328                 if (mddev->pers->check_reshape == NULL)
7329                         return -EINVAL;
7330                 else {
7331                         mddev->new_layout = info->layout;
7332                         rv = mddev->pers->check_reshape(mddev);
7333                         if (rv)
7334                                 mddev->new_layout = mddev->layout;
7335                         return rv;
7336                 }
7337         }
7338         if (info->size >= 0 && mddev->dev_sectors / 2 != info->size)
7339                 rv = update_size(mddev, (sector_t)info->size * 2);
7340
7341         if (mddev->raid_disks    != info->raid_disks)
7342                 rv = update_raid_disks(mddev, info->raid_disks);
7343
7344         if ((state ^ info->state) & (1<<MD_SB_BITMAP_PRESENT)) {
7345                 if (mddev->pers->quiesce == NULL || mddev->thread == NULL) {
7346                         rv = -EINVAL;
7347                         goto err;
7348                 }
7349                 if (mddev->recovery || mddev->sync_thread) {
7350                         rv = -EBUSY;
7351                         goto err;
7352                 }
7353                 if (info->state & (1<<MD_SB_BITMAP_PRESENT)) {
7354                         struct bitmap *bitmap;
7355                         /* add the bitmap */
7356                         if (mddev->bitmap) {
7357                                 rv = -EEXIST;
7358                                 goto err;
7359                         }
7360                         if (mddev->bitmap_info.default_offset == 0) {
7361                                 rv = -EINVAL;
7362                                 goto err;
7363                         }
7364                         mddev->bitmap_info.offset =
7365                                 mddev->bitmap_info.default_offset;
7366                         mddev->bitmap_info.space =
7367                                 mddev->bitmap_info.default_space;
7368                         bitmap = md_bitmap_create(mddev, -1);
7369                         mddev_suspend(mddev);
7370                         if (!IS_ERR(bitmap)) {
7371                                 mddev->bitmap = bitmap;
7372                                 rv = md_bitmap_load(mddev);
7373                         } else
7374                                 rv = PTR_ERR(bitmap);
7375                         if (rv)
7376                                 md_bitmap_destroy(mddev);
7377                         mddev_resume(mddev);
7378                 } else {
7379                         /* remove the bitmap */
7380                         if (!mddev->bitmap) {
7381                                 rv = -ENOENT;
7382                                 goto err;
7383                         }
7384                         if (mddev->bitmap->storage.file) {
7385                                 rv = -EINVAL;
7386                                 goto err;
7387                         }
7388                         if (mddev->bitmap_info.nodes) {
7389                                 /* hold PW on all the bitmap lock */
7390                                 if (md_cluster_ops->lock_all_bitmaps(mddev) <= 0) {
7391                                         pr_warn("md: can't change bitmap to none since the array is in use by more than one node\n");
7392                                         rv = -EPERM;
7393                                         md_cluster_ops->unlock_all_bitmaps(mddev);
7394                                         goto err;
7395                                 }
7396
7397                                 mddev->bitmap_info.nodes = 0;
7398                                 md_cluster_ops->leave(mddev);
7399                                 module_put(md_cluster_mod);
7400                                 mddev->safemode_delay = DEFAULT_SAFEMODE_DELAY;
7401                         }
7402                         mddev_suspend(mddev);
7403                         md_bitmap_destroy(mddev);
7404                         mddev_resume(mddev);
7405                         mddev->bitmap_info.offset = 0;
7406                 }
7407         }
7408         md_update_sb(mddev, 1);
7409         return rv;
7410 err:
7411         return rv;
7412 }
7413
7414 static int set_disk_faulty(struct mddev *mddev, dev_t dev)
7415 {
7416         struct md_rdev *rdev;
7417         int err = 0;
7418
7419         if (mddev->pers == NULL)
7420                 return -ENODEV;
7421
7422         rcu_read_lock();
7423         rdev = md_find_rdev_rcu(mddev, dev);
7424         if (!rdev)
7425                 err =  -ENODEV;
7426         else {
7427                 md_error(mddev, rdev);
7428                 if (!test_bit(Faulty, &rdev->flags))
7429                         err = -EBUSY;
7430         }
7431         rcu_read_unlock();
7432         return err;
7433 }
7434
7435 /*
7436  * We have a problem here : there is no easy way to give a CHS
7437  * virtual geometry. We currently pretend that we have a 2 heads
7438  * 4 sectors (with a BIG number of cylinders...). This drives
7439  * dosfs just mad... ;-)
7440  */
7441 static int md_getgeo(struct block_device *bdev, struct hd_geometry *geo)
7442 {
7443         struct mddev *mddev = bdev->bd_disk->private_data;
7444
7445         geo->heads = 2;
7446         geo->sectors = 4;
7447         geo->cylinders = mddev->array_sectors / 8;
7448         return 0;
7449 }
7450
7451 static inline bool md_ioctl_valid(unsigned int cmd)
7452 {
7453         switch (cmd) {
7454         case ADD_NEW_DISK:
7455         case GET_ARRAY_INFO:
7456         case GET_BITMAP_FILE:
7457         case GET_DISK_INFO:
7458         case HOT_ADD_DISK:
7459         case HOT_REMOVE_DISK:
7460         case RAID_VERSION:
7461         case RESTART_ARRAY_RW:
7462         case RUN_ARRAY:
7463         case SET_ARRAY_INFO:
7464         case SET_BITMAP_FILE:
7465         case SET_DISK_FAULTY:
7466         case STOP_ARRAY:
7467         case STOP_ARRAY_RO:
7468         case CLUSTERED_DISK_NACK:
7469                 return true;
7470         default:
7471                 return false;
7472         }
7473 }
7474
7475 static int md_ioctl(struct block_device *bdev, fmode_t mode,
7476                         unsigned int cmd, unsigned long arg)
7477 {
7478         int err = 0;
7479         void __user *argp = (void __user *)arg;
7480         struct mddev *mddev = NULL;
7481         bool did_set_md_closing = false;
7482
7483         if (!md_ioctl_valid(cmd))
7484                 return -ENOTTY;
7485
7486         switch (cmd) {
7487         case RAID_VERSION:
7488         case GET_ARRAY_INFO:
7489         case GET_DISK_INFO:
7490                 break;
7491         default:
7492                 if (!capable(CAP_SYS_ADMIN))
7493                         return -EACCES;
7494         }
7495
7496         /*
7497          * Commands dealing with the RAID driver but not any
7498          * particular array:
7499          */
7500         switch (cmd) {
7501         case RAID_VERSION:
7502                 err = get_version(argp);
7503                 goto out;
7504         default:;
7505         }
7506
7507         /*
7508          * Commands creating/starting a new array:
7509          */
7510
7511         mddev = bdev->bd_disk->private_data;
7512
7513         if (!mddev) {
7514                 BUG();
7515                 goto out;
7516         }
7517
7518         /* Some actions do not requires the mutex */
7519         switch (cmd) {
7520         case GET_ARRAY_INFO:
7521                 if (!mddev->raid_disks && !mddev->external)
7522                         err = -ENODEV;
7523                 else
7524                         err = get_array_info(mddev, argp);
7525                 goto out;
7526
7527         case GET_DISK_INFO:
7528                 if (!mddev->raid_disks && !mddev->external)
7529                         err = -ENODEV;
7530                 else
7531                         err = get_disk_info(mddev, argp);
7532                 goto out;
7533
7534         case SET_DISK_FAULTY:
7535                 err = set_disk_faulty(mddev, new_decode_dev(arg));
7536                 goto out;
7537
7538         case GET_BITMAP_FILE:
7539                 err = get_bitmap_file(mddev, argp);
7540                 goto out;
7541
7542         }
7543
7544         if (cmd == ADD_NEW_DISK || cmd == HOT_ADD_DISK)
7545                 flush_rdev_wq(mddev);
7546
7547         if (cmd == HOT_REMOVE_DISK)
7548                 /* need to ensure recovery thread has run */
7549                 wait_event_interruptible_timeout(mddev->sb_wait,
7550                                                  !test_bit(MD_RECOVERY_NEEDED,
7551                                                            &mddev->recovery),
7552                                                  msecs_to_jiffies(5000));
7553         if (cmd == STOP_ARRAY || cmd == STOP_ARRAY_RO) {
7554                 /* Need to flush page cache, and ensure no-one else opens
7555                  * and writes
7556                  */
7557                 mutex_lock(&mddev->open_mutex);
7558                 if (mddev->pers && atomic_read(&mddev->openers) > 1) {
7559                         mutex_unlock(&mddev->open_mutex);
7560                         err = -EBUSY;
7561                         goto out;
7562                 }
7563                 if (test_and_set_bit(MD_CLOSING, &mddev->flags)) {
7564                         mutex_unlock(&mddev->open_mutex);
7565                         err = -EBUSY;
7566                         goto out;
7567                 }
7568                 did_set_md_closing = true;
7569                 mutex_unlock(&mddev->open_mutex);
7570                 sync_blockdev(bdev);
7571         }
7572         err = mddev_lock(mddev);
7573         if (err) {
7574                 pr_debug("md: ioctl lock interrupted, reason %d, cmd %d\n",
7575                          err, cmd);
7576                 goto out;
7577         }
7578
7579         if (cmd == SET_ARRAY_INFO) {
7580                 mdu_array_info_t info;
7581                 if (!arg)
7582                         memset(&info, 0, sizeof(info));
7583                 else if (copy_from_user(&info, argp, sizeof(info))) {
7584                         err = -EFAULT;
7585                         goto unlock;
7586                 }
7587                 if (mddev->pers) {
7588                         err = update_array_info(mddev, &info);
7589                         if (err) {
7590                                 pr_warn("md: couldn't update array info. %d\n", err);
7591                                 goto unlock;
7592                         }
7593                         goto unlock;
7594                 }
7595                 if (!list_empty(&mddev->disks)) {
7596                         pr_warn("md: array %s already has disks!\n", mdname(mddev));
7597                         err = -EBUSY;
7598                         goto unlock;
7599                 }
7600                 if (mddev->raid_disks) {
7601                         pr_warn("md: array %s already initialised!\n", mdname(mddev));
7602                         err = -EBUSY;
7603                         goto unlock;
7604                 }
7605                 err = md_set_array_info(mddev, &info);
7606                 if (err) {
7607                         pr_warn("md: couldn't set array info. %d\n", err);
7608                         goto unlock;
7609                 }
7610                 goto unlock;
7611         }
7612
7613         /*
7614          * Commands querying/configuring an existing array:
7615          */
7616         /* if we are not initialised yet, only ADD_NEW_DISK, STOP_ARRAY,
7617          * RUN_ARRAY, and GET_ and SET_BITMAP_FILE are allowed */
7618         if ((!mddev->raid_disks && !mddev->external)
7619             && cmd != ADD_NEW_DISK && cmd != STOP_ARRAY
7620             && cmd != RUN_ARRAY && cmd != SET_BITMAP_FILE
7621             && cmd != GET_BITMAP_FILE) {
7622                 err = -ENODEV;
7623                 goto unlock;
7624         }
7625
7626         /*
7627          * Commands even a read-only array can execute:
7628          */
7629         switch (cmd) {
7630         case RESTART_ARRAY_RW:
7631                 err = restart_array(mddev);
7632                 goto unlock;
7633
7634         case STOP_ARRAY:
7635                 err = do_md_stop(mddev, 0, bdev);
7636                 goto unlock;
7637
7638         case STOP_ARRAY_RO:
7639                 err = md_set_readonly(mddev, bdev);
7640                 goto unlock;
7641
7642         case HOT_REMOVE_DISK:
7643                 err = hot_remove_disk(mddev, new_decode_dev(arg));
7644                 goto unlock;
7645
7646         case ADD_NEW_DISK:
7647                 /* We can support ADD_NEW_DISK on read-only arrays
7648                  * only if we are re-adding a preexisting device.
7649                  * So require mddev->pers and MD_DISK_SYNC.
7650                  */
7651                 if (mddev->pers) {
7652                         mdu_disk_info_t info;
7653                         if (copy_from_user(&info, argp, sizeof(info)))
7654                                 err = -EFAULT;
7655                         else if (!(info.state & (1<<MD_DISK_SYNC)))
7656                                 /* Need to clear read-only for this */
7657                                 break;
7658                         else
7659                                 err = md_add_new_disk(mddev, &info);
7660                         goto unlock;
7661                 }
7662                 break;
7663         }
7664
7665         /*
7666          * The remaining ioctls are changing the state of the
7667          * superblock, so we do not allow them on read-only arrays.
7668          */
7669         if (mddev->ro && mddev->pers) {
7670                 if (mddev->ro == 2) {
7671                         mddev->ro = 0;
7672                         sysfs_notify_dirent_safe(mddev->sysfs_state);
7673                         set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
7674                         /* mddev_unlock will wake thread */
7675                         /* If a device failed while we were read-only, we
7676                          * need to make sure the metadata is updated now.
7677                          */
7678                         if (test_bit(MD_SB_CHANGE_DEVS, &mddev->sb_flags)) {
7679                                 mddev_unlock(mddev);
7680                                 wait_event(mddev->sb_wait,
7681                                            !test_bit(MD_SB_CHANGE_DEVS, &mddev->sb_flags) &&
7682                                            !test_bit(MD_SB_CHANGE_PENDING, &mddev->sb_flags));
7683                                 mddev_lock_nointr(mddev);
7684                         }
7685                 } else {
7686                         err = -EROFS;
7687                         goto unlock;
7688                 }
7689         }
7690
7691         switch (cmd) {
7692         case ADD_NEW_DISK:
7693         {
7694                 mdu_disk_info_t info;
7695                 if (copy_from_user(&info, argp, sizeof(info)))
7696                         err = -EFAULT;
7697                 else
7698                         err = md_add_new_disk(mddev, &info);
7699                 goto unlock;
7700         }
7701
7702         case CLUSTERED_DISK_NACK:
7703                 if (mddev_is_clustered(mddev))
7704                         md_cluster_ops->new_disk_ack(mddev, false);
7705                 else
7706                         err = -EINVAL;
7707                 goto unlock;
7708
7709         case HOT_ADD_DISK:
7710                 err = hot_add_disk(mddev, new_decode_dev(arg));
7711                 goto unlock;
7712
7713         case RUN_ARRAY:
7714                 err = do_md_run(mddev);
7715                 goto unlock;
7716
7717         case SET_BITMAP_FILE:
7718                 err = set_bitmap_file(mddev, (int)arg);
7719                 goto unlock;
7720
7721         default:
7722                 err = -EINVAL;
7723                 goto unlock;
7724         }
7725
7726 unlock:
7727         if (mddev->hold_active == UNTIL_IOCTL &&
7728             err != -EINVAL)
7729                 mddev->hold_active = 0;
7730         mddev_unlock(mddev);
7731 out:
7732         if(did_set_md_closing)
7733                 clear_bit(MD_CLOSING, &mddev->flags);
7734         return err;
7735 }
7736 #ifdef CONFIG_COMPAT
7737 static int md_compat_ioctl(struct block_device *bdev, fmode_t mode,
7738                     unsigned int cmd, unsigned long arg)
7739 {
7740         switch (cmd) {
7741         case HOT_REMOVE_DISK:
7742         case HOT_ADD_DISK:
7743         case SET_DISK_FAULTY:
7744         case SET_BITMAP_FILE:
7745                 /* These take in integer arg, do not convert */
7746                 break;
7747         default:
7748                 arg = (unsigned long)compat_ptr(arg);
7749                 break;
7750         }
7751
7752         return md_ioctl(bdev, mode, cmd, arg);
7753 }
7754 #endif /* CONFIG_COMPAT */
7755
7756 static int md_set_read_only(struct block_device *bdev, bool ro)
7757 {
7758         struct mddev *mddev = bdev->bd_disk->private_data;
7759         int err;
7760
7761         err = mddev_lock(mddev);
7762         if (err)
7763                 return err;
7764
7765         if (!mddev->raid_disks && !mddev->external) {
7766                 err = -ENODEV;
7767                 goto out_unlock;
7768         }
7769
7770         /*
7771          * Transitioning to read-auto need only happen for arrays that call
7772          * md_write_start and which are not ready for writes yet.
7773          */
7774         if (!ro && mddev->ro == 1 && mddev->pers) {
7775                 err = restart_array(mddev);
7776                 if (err)
7777                         goto out_unlock;
7778                 mddev->ro = 2;
7779         }
7780
7781 out_unlock:
7782         mddev_unlock(mddev);
7783         return err;
7784 }
7785
7786 static int md_open(struct block_device *bdev, fmode_t mode)
7787 {
7788         /*
7789          * Succeed if we can lock the mddev, which confirms that
7790          * it isn't being stopped right now.
7791          */
7792         struct mddev *mddev = mddev_find(bdev->bd_dev);
7793         int err;
7794
7795         if (!mddev)
7796                 return -ENODEV;
7797
7798         if (mddev->gendisk != bdev->bd_disk) {
7799                 /* we are racing with mddev_put which is discarding this
7800                  * bd_disk.
7801                  */
7802                 mddev_put(mddev);
7803                 /* Wait until bdev->bd_disk is definitely gone */
7804                 if (work_pending(&mddev->del_work))
7805                         flush_workqueue(md_misc_wq);
7806                 return -EBUSY;
7807         }
7808         BUG_ON(mddev != bdev->bd_disk->private_data);
7809
7810         if ((err = mutex_lock_interruptible(&mddev->open_mutex)))
7811                 goto out;
7812
7813         if (test_bit(MD_CLOSING, &mddev->flags)) {
7814                 mutex_unlock(&mddev->open_mutex);
7815                 err = -ENODEV;
7816                 goto out;
7817         }
7818
7819         err = 0;
7820         atomic_inc(&mddev->openers);
7821         mutex_unlock(&mddev->open_mutex);
7822
7823         bdev_check_media_change(bdev);
7824  out:
7825         if (err)
7826                 mddev_put(mddev);
7827         return err;
7828 }
7829
7830 static void md_release(struct gendisk *disk, fmode_t mode)
7831 {
7832         struct mddev *mddev = disk->private_data;
7833
7834         BUG_ON(!mddev);
7835         atomic_dec(&mddev->openers);
7836         mddev_put(mddev);
7837 }
7838
7839 static unsigned int md_check_events(struct gendisk *disk, unsigned int clearing)
7840 {
7841         struct mddev *mddev = disk->private_data;
7842         unsigned int ret = 0;
7843
7844         if (mddev->changed)
7845                 ret = DISK_EVENT_MEDIA_CHANGE;
7846         mddev->changed = 0;
7847         return ret;
7848 }
7849
7850 const struct block_device_operations md_fops =
7851 {
7852         .owner          = THIS_MODULE,
7853         .submit_bio     = md_submit_bio,
7854         .open           = md_open,
7855         .release        = md_release,
7856         .ioctl          = md_ioctl,
7857 #ifdef CONFIG_COMPAT
7858         .compat_ioctl   = md_compat_ioctl,
7859 #endif
7860         .getgeo         = md_getgeo,
7861         .check_events   = md_check_events,
7862         .set_read_only  = md_set_read_only,
7863 };
7864
7865 static int md_thread(void *arg)
7866 {
7867         struct md_thread *thread = arg;
7868
7869         /*
7870          * md_thread is a 'system-thread', it's priority should be very
7871          * high. We avoid resource deadlocks individually in each
7872          * raid personality. (RAID5 does preallocation) We also use RR and
7873          * the very same RT priority as kswapd, thus we will never get
7874          * into a priority inversion deadlock.
7875          *
7876          * we definitely have to have equal or higher priority than
7877          * bdflush, otherwise bdflush will deadlock if there are too
7878          * many dirty RAID5 blocks.
7879          */
7880
7881         allow_signal(SIGKILL);
7882         while (!kthread_should_stop()) {
7883
7884                 /* We need to wait INTERRUPTIBLE so that
7885                  * we don't add to the load-average.
7886                  * That means we need to be sure no signals are
7887                  * pending
7888                  */
7889                 if (signal_pending(current))
7890                         flush_signals(current);
7891
7892                 wait_event_interruptible_timeout
7893                         (thread->wqueue,
7894                          test_bit(THREAD_WAKEUP, &thread->flags)
7895                          || kthread_should_stop() || kthread_should_park(),
7896                          thread->timeout);
7897
7898                 clear_bit(THREAD_WAKEUP, &thread->flags);
7899                 if (kthread_should_park())
7900                         kthread_parkme();
7901                 if (!kthread_should_stop())
7902                         thread->run(thread);
7903         }
7904
7905         return 0;
7906 }
7907
7908 void md_wakeup_thread(struct md_thread *thread)
7909 {
7910         if (thread) {
7911                 pr_debug("md: waking up MD thread %s.\n", thread->tsk->comm);
7912                 set_bit(THREAD_WAKEUP, &thread->flags);
7913                 wake_up(&thread->wqueue);
7914         }
7915 }
7916 EXPORT_SYMBOL(md_wakeup_thread);
7917
7918 struct md_thread *md_register_thread(void (*run) (struct md_thread *),
7919                 struct mddev *mddev, const char *name)
7920 {
7921         struct md_thread *thread;
7922
7923         thread = kzalloc(sizeof(struct md_thread), GFP_KERNEL);
7924         if (!thread)
7925                 return NULL;
7926
7927         init_waitqueue_head(&thread->wqueue);
7928
7929         thread->run = run;
7930         thread->mddev = mddev;
7931         thread->timeout = MAX_SCHEDULE_TIMEOUT;
7932         thread->tsk = kthread_run(md_thread, thread,
7933                                   "%s_%s",
7934                                   mdname(thread->mddev),
7935                                   name);
7936         if (IS_ERR(thread->tsk)) {
7937                 kfree(thread);
7938                 return NULL;
7939         }
7940         return thread;
7941 }
7942 EXPORT_SYMBOL(md_register_thread);
7943
7944 void md_unregister_thread(struct md_thread **threadp)
7945 {
7946         struct md_thread *thread = *threadp;
7947         if (!thread)
7948                 return;
7949         pr_debug("interrupting MD-thread pid %d\n", task_pid_nr(thread->tsk));
7950         /* Locking ensures that mddev_unlock does not wake_up a
7951          * non-existent thread
7952          */
7953         spin_lock(&pers_lock);
7954         *threadp = NULL;
7955         spin_unlock(&pers_lock);
7956
7957         kthread_stop(thread->tsk);
7958         kfree(thread);
7959 }
7960 EXPORT_SYMBOL(md_unregister_thread);
7961
7962 void md_error(struct mddev *mddev, struct md_rdev *rdev)
7963 {
7964         if (!rdev || test_bit(Faulty, &rdev->flags))
7965                 return;
7966
7967         if (!mddev->pers || !mddev->pers->error_handler)
7968                 return;
7969         mddev->pers->error_handler(mddev,rdev);
7970         if (mddev->degraded)
7971                 set_bit(MD_RECOVERY_RECOVER, &mddev->recovery);
7972         sysfs_notify_dirent_safe(rdev->sysfs_state);
7973         set_bit(MD_RECOVERY_INTR, &mddev->recovery);
7974         set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
7975         md_wakeup_thread(mddev->thread);
7976         if (mddev->event_work.func)
7977                 queue_work(md_misc_wq, &mddev->event_work);
7978         md_new_event(mddev);
7979 }
7980 EXPORT_SYMBOL(md_error);
7981
7982 /* seq_file implementation /proc/mdstat */
7983
7984 static void status_unused(struct seq_file *seq)
7985 {
7986         int i = 0;
7987         struct md_rdev *rdev;
7988
7989         seq_printf(seq, "unused devices: ");
7990
7991         list_for_each_entry(rdev, &pending_raid_disks, same_set) {
7992                 char b[BDEVNAME_SIZE];
7993                 i++;
7994                 seq_printf(seq, "%s ",
7995                               bdevname(rdev->bdev,b));
7996         }
7997         if (!i)
7998                 seq_printf(seq, "<none>");
7999
8000         seq_printf(seq, "\n");
8001 }
8002
8003 static int status_resync(struct seq_file *seq, struct mddev *mddev)
8004 {
8005         sector_t max_sectors, resync, res;
8006         unsigned long dt, db = 0;
8007         sector_t rt, curr_mark_cnt, resync_mark_cnt;
8008         int scale, recovery_active;
8009         unsigned int per_milli;
8010
8011         if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery) ||
8012             test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery))
8013                 max_sectors = mddev->resync_max_sectors;
8014         else
8015                 max_sectors = mddev->dev_sectors;
8016
8017         resync = mddev->curr_resync;
8018         if (resync <= 3) {
8019                 if (test_bit(MD_RECOVERY_DONE, &mddev->recovery))
8020                         /* Still cleaning up */
8021                         resync = max_sectors;
8022         } else if (resync > max_sectors)
8023                 resync = max_sectors;
8024         else
8025                 resync -= atomic_read(&mddev->recovery_active);
8026
8027         if (resync == 0) {
8028                 if (test_bit(MD_RESYNCING_REMOTE, &mddev->recovery)) {
8029                         struct md_rdev *rdev;
8030
8031                         rdev_for_each(rdev, mddev)
8032                                 if (rdev->raid_disk >= 0 &&
8033                                     !test_bit(Faulty, &rdev->flags) &&
8034                                     rdev->recovery_offset != MaxSector &&
8035                                     rdev->recovery_offset) {
8036                                         seq_printf(seq, "\trecover=REMOTE");
8037                                         return 1;
8038                                 }
8039                         if (mddev->reshape_position != MaxSector)
8040                                 seq_printf(seq, "\treshape=REMOTE");
8041                         else
8042                                 seq_printf(seq, "\tresync=REMOTE");
8043                         return 1;
8044                 }
8045                 if (mddev->recovery_cp < MaxSector) {
8046                         seq_printf(seq, "\tresync=PENDING");
8047                         return 1;
8048                 }
8049                 return 0;
8050         }
8051         if (resync < 3) {
8052                 seq_printf(seq, "\tresync=DELAYED");
8053                 return 1;
8054         }
8055
8056         WARN_ON(max_sectors == 0);
8057         /* Pick 'scale' such that (resync>>scale)*1000 will fit
8058          * in a sector_t, and (max_sectors>>scale) will fit in a
8059          * u32, as those are the requirements for sector_div.
8060          * Thus 'scale' must be at least 10
8061          */
8062         scale = 10;
8063         if (sizeof(sector_t) > sizeof(unsigned long)) {
8064                 while ( max_sectors/2 > (1ULL<<(scale+32)))
8065                         scale++;
8066         }
8067         res = (resync>>scale)*1000;
8068         sector_div(res, (u32)((max_sectors>>scale)+1));
8069
8070         per_milli = res;
8071         {
8072                 int i, x = per_milli/50, y = 20-x;
8073                 seq_printf(seq, "[");
8074                 for (i = 0; i < x; i++)
8075                         seq_printf(seq, "=");
8076                 seq_printf(seq, ">");
8077                 for (i = 0; i < y; i++)
8078                         seq_printf(seq, ".");
8079                 seq_printf(seq, "] ");
8080         }
8081         seq_printf(seq, " %s =%3u.%u%% (%llu/%llu)",
8082                    (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery)?
8083                     "reshape" :
8084                     (test_bit(MD_RECOVERY_CHECK, &mddev->recovery)?
8085                      "check" :
8086                      (test_bit(MD_RECOVERY_SYNC, &mddev->recovery) ?
8087                       "resync" : "recovery"))),
8088                    per_milli/10, per_milli % 10,
8089                    (unsigned long long) resync/2,
8090                    (unsigned long long) max_sectors/2);
8091
8092         /*
8093          * dt: time from mark until now
8094          * db: blocks written from mark until now
8095          * rt: remaining time
8096          *
8097          * rt is a sector_t, which is always 64bit now. We are keeping
8098          * the original algorithm, but it is not really necessary.
8099          *
8100          * Original algorithm:
8101          *   So we divide before multiply in case it is 32bit and close
8102          *   to the limit.
8103          *   We scale the divisor (db) by 32 to avoid losing precision
8104          *   near the end of resync when the number of remaining sectors
8105          *   is close to 'db'.
8106          *   We then divide rt by 32 after multiplying by db to compensate.
8107          *   The '+1' avoids division by zero if db is very small.
8108          */
8109         dt = ((jiffies - mddev->resync_mark) / HZ);
8110         if (!dt) dt++;
8111
8112         curr_mark_cnt = mddev->curr_mark_cnt;
8113         recovery_active = atomic_read(&mddev->recovery_active);
8114         resync_mark_cnt = mddev->resync_mark_cnt;
8115
8116         if (curr_mark_cnt >= (recovery_active + resync_mark_cnt))
8117                 db = curr_mark_cnt - (recovery_active + resync_mark_cnt);
8118
8119         rt = max_sectors - resync;    /* number of remaining sectors */
8120         rt = div64_u64(rt, db/32+1);
8121         rt *= dt;
8122         rt >>= 5;
8123
8124         seq_printf(seq, " finish=%lu.%lumin", (unsigned long)rt / 60,
8125                    ((unsigned long)rt % 60)/6);
8126
8127         seq_printf(seq, " speed=%ldK/sec", db/2/dt);
8128         return 1;
8129 }
8130
8131 static void *md_seq_start(struct seq_file *seq, loff_t *pos)
8132 {
8133         struct list_head *tmp;
8134         loff_t l = *pos;
8135         struct mddev *mddev;
8136
8137         if (l == 0x10000) {
8138                 ++*pos;
8139                 return (void *)2;
8140         }
8141         if (l > 0x10000)
8142                 return NULL;
8143         if (!l--)
8144                 /* header */
8145                 return (void*)1;
8146
8147         spin_lock(&all_mddevs_lock);
8148         list_for_each(tmp,&all_mddevs)
8149                 if (!l--) {
8150                         mddev = list_entry(tmp, struct mddev, all_mddevs);
8151                         mddev_get(mddev);
8152                         spin_unlock(&all_mddevs_lock);
8153                         return mddev;
8154                 }
8155         spin_unlock(&all_mddevs_lock);
8156         if (!l--)
8157                 return (void*)2;/* tail */
8158         return NULL;
8159 }
8160
8161 static void *md_seq_next(struct seq_file *seq, void *v, loff_t *pos)
8162 {
8163         struct list_head *tmp;
8164         struct mddev *next_mddev, *mddev = v;
8165
8166         ++*pos;
8167         if (v == (void*)2)
8168                 return NULL;
8169
8170         spin_lock(&all_mddevs_lock);
8171         if (v == (void*)1)
8172                 tmp = all_mddevs.next;
8173         else
8174                 tmp = mddev->all_mddevs.next;
8175         if (tmp != &all_mddevs)
8176                 next_mddev = mddev_get(list_entry(tmp,struct mddev,all_mddevs));
8177         else {
8178                 next_mddev = (void*)2;
8179                 *pos = 0x10000;
8180         }
8181         spin_unlock(&all_mddevs_lock);
8182
8183         if (v != (void*)1)
8184                 mddev_put(mddev);
8185         return next_mddev;
8186
8187 }
8188
8189 static void md_seq_stop(struct seq_file *seq, void *v)
8190 {
8191         struct mddev *mddev = v;
8192
8193         if (mddev && v != (void*)1 && v != (void*)2)
8194                 mddev_put(mddev);
8195 }
8196
8197 static int md_seq_show(struct seq_file *seq, void *v)
8198 {
8199         struct mddev *mddev = v;
8200         sector_t sectors;
8201         struct md_rdev *rdev;
8202
8203         if (v == (void*)1) {
8204                 struct md_personality *pers;
8205                 seq_printf(seq, "Personalities : ");
8206                 spin_lock(&pers_lock);
8207                 list_for_each_entry(pers, &pers_list, list)
8208                         seq_printf(seq, "[%s] ", pers->name);
8209
8210                 spin_unlock(&pers_lock);
8211                 seq_printf(seq, "\n");
8212                 seq->poll_event = atomic_read(&md_event_count);
8213                 return 0;
8214         }
8215         if (v == (void*)2) {
8216                 status_unused(seq);
8217                 return 0;
8218         }
8219
8220         spin_lock(&mddev->lock);
8221         if (mddev->pers || mddev->raid_disks || !list_empty(&mddev->disks)) {
8222                 seq_printf(seq, "%s : %sactive", mdname(mddev),
8223                                                 mddev->pers ? "" : "in");
8224                 if (mddev->pers) {
8225                         if (mddev->ro==1)
8226                                 seq_printf(seq, " (read-only)");
8227                         if (mddev->ro==2)
8228                                 seq_printf(seq, " (auto-read-only)");
8229                         seq_printf(seq, " %s", mddev->pers->name);
8230                 }
8231
8232                 sectors = 0;
8233                 rcu_read_lock();
8234                 rdev_for_each_rcu(rdev, mddev) {
8235                         char b[BDEVNAME_SIZE];
8236                         seq_printf(seq, " %s[%d]",
8237                                 bdevname(rdev->bdev,b), rdev->desc_nr);
8238                         if (test_bit(WriteMostly, &rdev->flags))
8239                                 seq_printf(seq, "(W)");
8240                         if (test_bit(Journal, &rdev->flags))
8241                                 seq_printf(seq, "(J)");
8242                         if (test_bit(Faulty, &rdev->flags)) {
8243                                 seq_printf(seq, "(F)");
8244                                 continue;
8245                         }
8246                         if (rdev->raid_disk < 0)
8247                                 seq_printf(seq, "(S)"); /* spare */
8248                         if (test_bit(Replacement, &rdev->flags))
8249                                 seq_printf(seq, "(R)");
8250                         sectors += rdev->sectors;
8251                 }
8252                 rcu_read_unlock();
8253
8254                 if (!list_empty(&mddev->disks)) {
8255                         if (mddev->pers)
8256                                 seq_printf(seq, "\n      %llu blocks",
8257                                            (unsigned long long)
8258                                            mddev->array_sectors / 2);
8259                         else
8260                                 seq_printf(seq, "\n      %llu blocks",
8261                                            (unsigned long long)sectors / 2);
8262                 }
8263                 if (mddev->persistent) {
8264                         if (mddev->major_version != 0 ||
8265                             mddev->minor_version != 90) {
8266                                 seq_printf(seq," super %d.%d",
8267                                            mddev->major_version,
8268                                            mddev->minor_version);
8269                         }
8270                 } else if (mddev->external)
8271                         seq_printf(seq, " super external:%s",
8272                                    mddev->metadata_type);
8273                 else
8274                         seq_printf(seq, " super non-persistent");
8275
8276                 if (mddev->pers) {
8277                         mddev->pers->status(seq, mddev);
8278                         seq_printf(seq, "\n      ");
8279                         if (mddev->pers->sync_request) {
8280                                 if (status_resync(seq, mddev))
8281                                         seq_printf(seq, "\n      ");
8282                         }
8283                 } else
8284                         seq_printf(seq, "\n       ");
8285
8286                 md_bitmap_status(seq, mddev->bitmap);
8287
8288                 seq_printf(seq, "\n");
8289         }
8290         spin_unlock(&mddev->lock);
8291
8292         return 0;
8293 }
8294
8295 static const struct seq_operations md_seq_ops = {
8296         .start  = md_seq_start,
8297         .next   = md_seq_next,
8298         .stop   = md_seq_stop,
8299         .show   = md_seq_show,
8300 };
8301
8302 static int md_seq_open(struct inode *inode, struct file *file)
8303 {
8304         struct seq_file *seq;
8305         int error;
8306
8307         error = seq_open(file, &md_seq_ops);
8308         if (error)
8309                 return error;
8310
8311         seq = file->private_data;
8312         seq->poll_event = atomic_read(&md_event_count);
8313         return error;
8314 }
8315
8316 static int md_unloading;
8317 static __poll_t mdstat_poll(struct file *filp, poll_table *wait)
8318 {
8319         struct seq_file *seq = filp->private_data;
8320         __poll_t mask;
8321
8322         if (md_unloading)
8323                 return EPOLLIN|EPOLLRDNORM|EPOLLERR|EPOLLPRI;
8324         poll_wait(filp, &md_event_waiters, wait);
8325
8326         /* always allow read */
8327         mask = EPOLLIN | EPOLLRDNORM;
8328
8329         if (seq->poll_event != atomic_read(&md_event_count))
8330                 mask |= EPOLLERR | EPOLLPRI;
8331         return mask;
8332 }
8333
8334 static const struct proc_ops mdstat_proc_ops = {
8335         .proc_open      = md_seq_open,
8336         .proc_read      = seq_read,
8337         .proc_lseek     = seq_lseek,
8338         .proc_release   = seq_release,
8339         .proc_poll      = mdstat_poll,
8340 };
8341
8342 int register_md_personality(struct md_personality *p)
8343 {
8344         pr_debug("md: %s personality registered for level %d\n",
8345                  p->name, p->level);
8346         spin_lock(&pers_lock);
8347         list_add_tail(&p->list, &pers_list);
8348         spin_unlock(&pers_lock);
8349         return 0;
8350 }
8351 EXPORT_SYMBOL(register_md_personality);
8352
8353 int unregister_md_personality(struct md_personality *p)
8354 {
8355         pr_debug("md: %s personality unregistered\n", p->name);
8356         spin_lock(&pers_lock);
8357         list_del_init(&p->list);
8358         spin_unlock(&pers_lock);
8359         return 0;
8360 }
8361 EXPORT_SYMBOL(unregister_md_personality);
8362
8363 int register_md_cluster_operations(struct md_cluster_operations *ops,
8364                                    struct module *module)
8365 {
8366         int ret = 0;
8367         spin_lock(&pers_lock);
8368         if (md_cluster_ops != NULL)
8369                 ret = -EALREADY;
8370         else {
8371                 md_cluster_ops = ops;
8372                 md_cluster_mod = module;
8373         }
8374         spin_unlock(&pers_lock);
8375         return ret;
8376 }
8377 EXPORT_SYMBOL(register_md_cluster_operations);
8378
8379 int unregister_md_cluster_operations(void)
8380 {
8381         spin_lock(&pers_lock);
8382         md_cluster_ops = NULL;
8383         spin_unlock(&pers_lock);
8384         return 0;
8385 }
8386 EXPORT_SYMBOL(unregister_md_cluster_operations);
8387
8388 int md_setup_cluster(struct mddev *mddev, int nodes)
8389 {
8390         int ret;
8391         if (!md_cluster_ops)
8392                 request_module("md-cluster");
8393         spin_lock(&pers_lock);
8394         /* ensure module won't be unloaded */
8395         if (!md_cluster_ops || !try_module_get(md_cluster_mod)) {
8396                 pr_warn("can't find md-cluster module or get it's reference.\n");
8397                 spin_unlock(&pers_lock);
8398                 return -ENOENT;
8399         }
8400         spin_unlock(&pers_lock);
8401
8402         ret = md_cluster_ops->join(mddev, nodes);
8403         if (!ret)
8404                 mddev->safemode_delay = 0;
8405         return ret;
8406 }
8407
8408 void md_cluster_stop(struct mddev *mddev)
8409 {
8410         if (!md_cluster_ops)
8411                 return;
8412         md_cluster_ops->leave(mddev);
8413         module_put(md_cluster_mod);
8414 }
8415
8416 static int is_mddev_idle(struct mddev *mddev, int init)
8417 {
8418         struct md_rdev *rdev;
8419         int idle;
8420         int curr_events;
8421
8422         idle = 1;
8423         rcu_read_lock();
8424         rdev_for_each_rcu(rdev, mddev) {
8425                 struct gendisk *disk = rdev->bdev->bd_disk;
8426                 curr_events = (int)part_stat_read_accum(disk->part0, sectors) -
8427                               atomic_read(&disk->sync_io);
8428                 /* sync IO will cause sync_io to increase before the disk_stats
8429                  * as sync_io is counted when a request starts, and
8430                  * disk_stats is counted when it completes.
8431                  * So resync activity will cause curr_events to be smaller than
8432                  * when there was no such activity.
8433                  * non-sync IO will cause disk_stat to increase without
8434                  * increasing sync_io so curr_events will (eventually)
8435                  * be larger than it was before.  Once it becomes
8436                  * substantially larger, the test below will cause
8437                  * the array to appear non-idle, and resync will slow
8438                  * down.
8439                  * If there is a lot of outstanding resync activity when
8440                  * we set last_event to curr_events, then all that activity
8441                  * completing might cause the array to appear non-idle
8442                  * and resync will be slowed down even though there might
8443                  * not have been non-resync activity.  This will only
8444                  * happen once though.  'last_events' will soon reflect
8445                  * the state where there is little or no outstanding
8446                  * resync requests, and further resync activity will
8447                  * always make curr_events less than last_events.
8448                  *
8449                  */
8450                 if (init || curr_events - rdev->last_events > 64) {
8451                         rdev->last_events = curr_events;
8452                         idle = 0;
8453                 }
8454         }
8455         rcu_read_unlock();
8456         return idle;
8457 }
8458
8459 void md_done_sync(struct mddev *mddev, int blocks, int ok)
8460 {
8461         /* another "blocks" (512byte) blocks have been synced */
8462         atomic_sub(blocks, &mddev->recovery_active);
8463         wake_up(&mddev->recovery_wait);
8464         if (!ok) {
8465                 set_bit(MD_RECOVERY_INTR, &mddev->recovery);
8466                 set_bit(MD_RECOVERY_ERROR, &mddev->recovery);
8467                 md_wakeup_thread(mddev->thread);
8468                 // stop recovery, signal do_sync ....
8469         }
8470 }
8471 EXPORT_SYMBOL(md_done_sync);
8472
8473 /* md_write_start(mddev, bi)
8474  * If we need to update some array metadata (e.g. 'active' flag
8475  * in superblock) before writing, schedule a superblock update
8476  * and wait for it to complete.
8477  * A return value of 'false' means that the write wasn't recorded
8478  * and cannot proceed as the array is being suspend.
8479  */
8480 bool md_write_start(struct mddev *mddev, struct bio *bi)
8481 {
8482         int did_change = 0;
8483
8484         if (bio_data_dir(bi) != WRITE)
8485                 return true;
8486
8487         BUG_ON(mddev->ro == 1);
8488         if (mddev->ro == 2) {
8489                 /* need to switch to read/write */
8490                 mddev->ro = 0;
8491                 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
8492                 md_wakeup_thread(mddev->thread);
8493                 md_wakeup_thread(mddev->sync_thread);
8494                 did_change = 1;
8495         }
8496         rcu_read_lock();
8497         percpu_ref_get(&mddev->writes_pending);
8498         smp_mb(); /* Match smp_mb in set_in_sync() */
8499         if (mddev->safemode == 1)
8500                 mddev->safemode = 0;
8501         /* sync_checkers is always 0 when writes_pending is in per-cpu mode */
8502         if (mddev->in_sync || mddev->sync_checkers) {
8503                 spin_lock(&mddev->lock);
8504                 if (mddev->in_sync) {
8505                         mddev->in_sync = 0;
8506                         set_bit(MD_SB_CHANGE_CLEAN, &mddev->sb_flags);
8507                         set_bit(MD_SB_CHANGE_PENDING, &mddev->sb_flags);
8508                         md_wakeup_thread(mddev->thread);
8509                         did_change = 1;
8510                 }
8511                 spin_unlock(&mddev->lock);
8512         }
8513         rcu_read_unlock();
8514         if (did_change)
8515                 sysfs_notify_dirent_safe(mddev->sysfs_state);
8516         if (!mddev->has_superblocks)
8517                 return true;
8518         wait_event(mddev->sb_wait,
8519                    !test_bit(MD_SB_CHANGE_PENDING, &mddev->sb_flags) ||
8520                    mddev->suspended);
8521         if (test_bit(MD_SB_CHANGE_PENDING, &mddev->sb_flags)) {
8522                 percpu_ref_put(&mddev->writes_pending);
8523                 return false;
8524         }
8525         return true;
8526 }
8527 EXPORT_SYMBOL(md_write_start);
8528
8529 /* md_write_inc can only be called when md_write_start() has
8530  * already been called at least once of the current request.
8531  * It increments the counter and is useful when a single request
8532  * is split into several parts.  Each part causes an increment and
8533  * so needs a matching md_write_end().
8534  * Unlike md_write_start(), it is safe to call md_write_inc() inside
8535  * a spinlocked region.
8536  */
8537 void md_write_inc(struct mddev *mddev, struct bio *bi)
8538 {
8539         if (bio_data_dir(bi) != WRITE)
8540                 return;
8541         WARN_ON_ONCE(mddev->in_sync || mddev->ro);
8542         percpu_ref_get(&mddev->writes_pending);
8543 }
8544 EXPORT_SYMBOL(md_write_inc);
8545
8546 void md_write_end(struct mddev *mddev)
8547 {
8548         percpu_ref_put(&mddev->writes_pending);
8549
8550         if (mddev->safemode == 2)
8551                 md_wakeup_thread(mddev->thread);
8552         else if (mddev->safemode_delay)
8553                 /* The roundup() ensures this only performs locking once
8554                  * every ->safemode_delay jiffies
8555                  */
8556                 mod_timer(&mddev->safemode_timer,
8557                           roundup(jiffies, mddev->safemode_delay) +
8558                           mddev->safemode_delay);
8559 }
8560
8561 EXPORT_SYMBOL(md_write_end);
8562
8563 /* This is used by raid0 and raid10 */
8564 void md_submit_discard_bio(struct mddev *mddev, struct md_rdev *rdev,
8565                         struct bio *bio, sector_t start, sector_t size)
8566 {
8567         struct bio *discard_bio = NULL;
8568
8569         if (__blkdev_issue_discard(rdev->bdev, start, size, GFP_NOIO, 0,
8570                         &discard_bio) || !discard_bio)
8571                 return;
8572
8573         bio_chain(discard_bio, bio);
8574         bio_clone_blkg_association(discard_bio, bio);
8575         if (mddev->gendisk)
8576                 trace_block_bio_remap(discard_bio,
8577                                 disk_devt(mddev->gendisk),
8578                                 bio->bi_iter.bi_sector);
8579         submit_bio_noacct(discard_bio);
8580 }
8581 EXPORT_SYMBOL_GPL(md_submit_discard_bio);
8582
8583 static void md_end_io_acct(struct bio *bio)
8584 {
8585         struct md_io_acct *md_io_acct = bio->bi_private;
8586         struct bio *orig_bio = md_io_acct->orig_bio;
8587
8588         orig_bio->bi_status = bio->bi_status;
8589
8590         bio_end_io_acct(orig_bio, md_io_acct->start_time);
8591         bio_put(bio);
8592         bio_endio(orig_bio);
8593 }
8594
8595 /*
8596  * Used by personalities that don't already clone the bio and thus can't
8597  * easily add the timestamp to their extended bio structure.
8598  */
8599 void md_account_bio(struct mddev *mddev, struct bio **bio)
8600 {
8601         struct md_io_acct *md_io_acct;
8602         struct bio *clone;
8603
8604         if (!blk_queue_io_stat((*bio)->bi_bdev->bd_disk->queue))
8605                 return;
8606
8607         clone = bio_clone_fast(*bio, GFP_NOIO, &mddev->io_acct_set);
8608         md_io_acct = container_of(clone, struct md_io_acct, bio_clone);
8609         md_io_acct->orig_bio = *bio;
8610         md_io_acct->start_time = bio_start_io_acct(*bio);
8611
8612         clone->bi_end_io = md_end_io_acct;
8613         clone->bi_private = md_io_acct;
8614         *bio = clone;
8615 }
8616 EXPORT_SYMBOL_GPL(md_account_bio);
8617
8618 /* md_allow_write(mddev)
8619  * Calling this ensures that the array is marked 'active' so that writes
8620  * may proceed without blocking.  It is important to call this before
8621  * attempting a GFP_KERNEL allocation while holding the mddev lock.
8622  * Must be called with mddev_lock held.
8623  */
8624 void md_allow_write(struct mddev *mddev)
8625 {
8626         if (!mddev->pers)
8627                 return;
8628         if (mddev->ro)
8629                 return;
8630         if (!mddev->pers->sync_request)
8631                 return;
8632
8633         spin_lock(&mddev->lock);
8634         if (mddev->in_sync) {
8635                 mddev->in_sync = 0;
8636                 set_bit(MD_SB_CHANGE_CLEAN, &mddev->sb_flags);
8637                 set_bit(MD_SB_CHANGE_PENDING, &mddev->sb_flags);
8638                 if (mddev->safemode_delay &&
8639                     mddev->safemode == 0)
8640                         mddev->safemode = 1;
8641                 spin_unlock(&mddev->lock);
8642                 md_update_sb(mddev, 0);
8643                 sysfs_notify_dirent_safe(mddev->sysfs_state);
8644                 /* wait for the dirty state to be recorded in the metadata */
8645                 wait_event(mddev->sb_wait,
8646                            !test_bit(MD_SB_CHANGE_PENDING, &mddev->sb_flags));
8647         } else
8648                 spin_unlock(&mddev->lock);
8649 }
8650 EXPORT_SYMBOL_GPL(md_allow_write);
8651
8652 #define SYNC_MARKS      10
8653 #define SYNC_MARK_STEP  (3*HZ)
8654 #define UPDATE_FREQUENCY (5*60*HZ)
8655 void md_do_sync(struct md_thread *thread)
8656 {
8657         struct mddev *mddev = thread->mddev;
8658         struct mddev *mddev2;
8659         unsigned int currspeed = 0, window;
8660         sector_t max_sectors,j, io_sectors, recovery_done;
8661         unsigned long mark[SYNC_MARKS];
8662         unsigned long update_time;
8663         sector_t mark_cnt[SYNC_MARKS];
8664         int last_mark,m;
8665         struct list_head *tmp;
8666         sector_t last_check;
8667         int skipped = 0;
8668         struct md_rdev *rdev;
8669         char *desc, *action = NULL;
8670         struct blk_plug plug;
8671         int ret;
8672
8673         /* just incase thread restarts... */
8674         if (test_bit(MD_RECOVERY_DONE, &mddev->recovery) ||
8675             test_bit(MD_RECOVERY_WAIT, &mddev->recovery))
8676                 return;
8677         if (mddev->ro) {/* never try to sync a read-only array */
8678                 set_bit(MD_RECOVERY_INTR, &mddev->recovery);
8679                 return;
8680         }
8681
8682         if (mddev_is_clustered(mddev)) {
8683                 ret = md_cluster_ops->resync_start(mddev);
8684                 if (ret)
8685                         goto skip;
8686
8687                 set_bit(MD_CLUSTER_RESYNC_LOCKED, &mddev->flags);
8688                 if (!(test_bit(MD_RECOVERY_SYNC, &mddev->recovery) ||
8689                         test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery) ||
8690                         test_bit(MD_RECOVERY_RECOVER, &mddev->recovery))
8691                      && ((unsigned long long)mddev->curr_resync_completed
8692                          < (unsigned long long)mddev->resync_max_sectors))
8693                         goto skip;
8694         }
8695
8696         if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery)) {
8697                 if (test_bit(MD_RECOVERY_CHECK, &mddev->recovery)) {
8698                         desc = "data-check";
8699                         action = "check";
8700                 } else if (test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery)) {
8701                         desc = "requested-resync";
8702                         action = "repair";
8703                 } else
8704                         desc = "resync";
8705         } else if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery))
8706                 desc = "reshape";
8707         else
8708                 desc = "recovery";
8709
8710         mddev->last_sync_action = action ?: desc;
8711
8712         /* we overload curr_resync somewhat here.
8713          * 0 == not engaged in resync at all
8714          * 2 == checking that there is no conflict with another sync
8715          * 1 == like 2, but have yielded to allow conflicting resync to
8716          *              commence
8717          * other == active in resync - this many blocks
8718          *
8719          * Before starting a resync we must have set curr_resync to
8720          * 2, and then checked that every "conflicting" array has curr_resync
8721          * less than ours.  When we find one that is the same or higher
8722          * we wait on resync_wait.  To avoid deadlock, we reduce curr_resync
8723          * to 1 if we choose to yield (based arbitrarily on address of mddev structure).
8724          * This will mean we have to start checking from the beginning again.
8725          *
8726          */
8727
8728         do {
8729                 int mddev2_minor = -1;
8730                 mddev->curr_resync = 2;
8731
8732         try_again:
8733                 if (test_bit(MD_RECOVERY_INTR, &mddev->recovery))
8734                         goto skip;
8735                 for_each_mddev(mddev2, tmp) {
8736                         if (mddev2 == mddev)
8737                                 continue;
8738                         if (!mddev->parallel_resync
8739                         &&  mddev2->curr_resync
8740                         &&  match_mddev_units(mddev, mddev2)) {
8741                                 DEFINE_WAIT(wq);
8742                                 if (mddev < mddev2 && mddev->curr_resync == 2) {
8743                                         /* arbitrarily yield */
8744                                         mddev->curr_resync = 1;
8745                                         wake_up(&resync_wait);
8746                                 }
8747                                 if (mddev > mddev2 && mddev->curr_resync == 1)
8748                                         /* no need to wait here, we can wait the next
8749                                          * time 'round when curr_resync == 2
8750                                          */
8751                                         continue;
8752                                 /* We need to wait 'interruptible' so as not to
8753                                  * contribute to the load average, and not to
8754                                  * be caught by 'softlockup'
8755                                  */
8756                                 prepare_to_wait(&resync_wait, &wq, TASK_INTERRUPTIBLE);
8757                                 if (!test_bit(MD_RECOVERY_INTR, &mddev->recovery) &&
8758                                     mddev2->curr_resync >= mddev->curr_resync) {
8759                                         if (mddev2_minor != mddev2->md_minor) {
8760                                                 mddev2_minor = mddev2->md_minor;
8761                                                 pr_info("md: delaying %s of %s until %s has finished (they share one or more physical units)\n",
8762                                                         desc, mdname(mddev),
8763                                                         mdname(mddev2));
8764                                         }
8765                                         mddev_put(mddev2);
8766                                         if (signal_pending(current))
8767                                                 flush_signals(current);
8768                                         schedule();
8769                                         finish_wait(&resync_wait, &wq);
8770                                         goto try_again;
8771                                 }
8772                                 finish_wait(&resync_wait, &wq);
8773                         }
8774                 }
8775         } while (mddev->curr_resync < 2);
8776
8777         j = 0;
8778         if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery)) {
8779                 /* resync follows the size requested by the personality,
8780                  * which defaults to physical size, but can be virtual size
8781                  */
8782                 max_sectors = mddev->resync_max_sectors;
8783                 atomic64_set(&mddev->resync_mismatches, 0);
8784                 /* we don't use the checkpoint if there's a bitmap */
8785                 if (test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery))
8786                         j = mddev->resync_min;
8787                 else if (!mddev->bitmap)
8788                         j = mddev->recovery_cp;
8789
8790         } else if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery)) {
8791                 max_sectors = mddev->resync_max_sectors;
8792                 /*
8793                  * If the original node aborts reshaping then we continue the
8794                  * reshaping, so set j again to avoid restart reshape from the
8795                  * first beginning
8796                  */
8797                 if (mddev_is_clustered(mddev) &&
8798                     mddev->reshape_position != MaxSector)
8799                         j = mddev->reshape_position;
8800         } else {
8801                 /* recovery follows the physical size of devices */
8802                 max_sectors = mddev->dev_sectors;
8803                 j = MaxSector;
8804                 rcu_read_lock();
8805                 rdev_for_each_rcu(rdev, mddev)
8806                         if (rdev->raid_disk >= 0 &&
8807                             !test_bit(Journal, &rdev->flags) &&
8808                             !test_bit(Faulty, &rdev->flags) &&
8809                             !test_bit(In_sync, &rdev->flags) &&
8810                             rdev->recovery_offset < j)
8811                                 j = rdev->recovery_offset;
8812                 rcu_read_unlock();
8813
8814                 /* If there is a bitmap, we need to make sure all
8815                  * writes that started before we added a spare
8816                  * complete before we start doing a recovery.
8817                  * Otherwise the write might complete and (via
8818                  * bitmap_endwrite) set a bit in the bitmap after the
8819                  * recovery has checked that bit and skipped that
8820                  * region.
8821                  */
8822                 if (mddev->bitmap) {
8823                         mddev->pers->quiesce(mddev, 1);
8824                         mddev->pers->quiesce(mddev, 0);
8825                 }
8826         }
8827
8828         pr_info("md: %s of RAID array %s\n", desc, mdname(mddev));
8829         pr_debug("md: minimum _guaranteed_  speed: %d KB/sec/disk.\n", speed_min(mddev));
8830         pr_debug("md: using maximum available idle IO bandwidth (but not more than %d KB/sec) for %s.\n",
8831                  speed_max(mddev), desc);
8832
8833         is_mddev_idle(mddev, 1); /* this initializes IO event counters */
8834
8835         io_sectors = 0;
8836         for (m = 0; m < SYNC_MARKS; m++) {
8837                 mark[m] = jiffies;
8838                 mark_cnt[m] = io_sectors;
8839         }
8840         last_mark = 0;
8841         mddev->resync_mark = mark[last_mark];
8842         mddev->resync_mark_cnt = mark_cnt[last_mark];
8843
8844         /*
8845          * Tune reconstruction:
8846          */
8847         window = 32 * (PAGE_SIZE / 512);
8848         pr_debug("md: using %dk window, over a total of %lluk.\n",
8849                  window/2, (unsigned long long)max_sectors/2);
8850
8851         atomic_set(&mddev->recovery_active, 0);
8852         last_check = 0;
8853
8854         if (j>2) {
8855                 pr_debug("md: resuming %s of %s from checkpoint.\n",
8856                          desc, mdname(mddev));
8857                 mddev->curr_resync = j;
8858         } else
8859                 mddev->curr_resync = 3; /* no longer delayed */
8860         mddev->curr_resync_completed = j;
8861         sysfs_notify_dirent_safe(mddev->sysfs_completed);
8862         md_new_event(mddev);
8863         update_time = jiffies;
8864
8865         blk_start_plug(&plug);
8866         while (j < max_sectors) {
8867                 sector_t sectors;
8868
8869                 skipped = 0;
8870
8871                 if (!test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery) &&
8872                     ((mddev->curr_resync > mddev->curr_resync_completed &&
8873                       (mddev->curr_resync - mddev->curr_resync_completed)
8874                       > (max_sectors >> 4)) ||
8875                      time_after_eq(jiffies, update_time + UPDATE_FREQUENCY) ||
8876                      (j - mddev->curr_resync_completed)*2
8877                      >= mddev->resync_max - mddev->curr_resync_completed ||
8878                      mddev->curr_resync_completed > mddev->resync_max
8879                             )) {
8880                         /* time to update curr_resync_completed */
8881                         wait_event(mddev->recovery_wait,
8882                                    atomic_read(&mddev->recovery_active) == 0);
8883                         mddev->curr_resync_completed = j;
8884                         if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery) &&
8885                             j > mddev->recovery_cp)
8886                                 mddev->recovery_cp = j;
8887                         update_time = jiffies;
8888                         set_bit(MD_SB_CHANGE_CLEAN, &mddev->sb_flags);
8889                         sysfs_notify_dirent_safe(mddev->sysfs_completed);
8890                 }
8891
8892                 while (j >= mddev->resync_max &&
8893                        !test_bit(MD_RECOVERY_INTR, &mddev->recovery)) {
8894                         /* As this condition is controlled by user-space,
8895                          * we can block indefinitely, so use '_interruptible'
8896                          * to avoid triggering warnings.
8897                          */
8898                         flush_signals(current); /* just in case */
8899                         wait_event_interruptible(mddev->recovery_wait,
8900                                                  mddev->resync_max > j
8901                                                  || test_bit(MD_RECOVERY_INTR,
8902                                                              &mddev->recovery));
8903                 }
8904
8905                 if (test_bit(MD_RECOVERY_INTR, &mddev->recovery))
8906                         break;
8907
8908                 sectors = mddev->pers->sync_request(mddev, j, &skipped);
8909                 if (sectors == 0) {
8910                         set_bit(MD_RECOVERY_INTR, &mddev->recovery);
8911                         break;
8912                 }
8913
8914                 if (!skipped) { /* actual IO requested */
8915                         io_sectors += sectors;
8916                         atomic_add(sectors, &mddev->recovery_active);
8917                 }
8918
8919                 if (test_bit(MD_RECOVERY_INTR, &mddev->recovery))
8920                         break;
8921
8922                 j += sectors;
8923                 if (j > max_sectors)
8924                         /* when skipping, extra large numbers can be returned. */
8925                         j = max_sectors;
8926                 if (j > 2)
8927                         mddev->curr_resync = j;
8928                 mddev->curr_mark_cnt = io_sectors;
8929                 if (last_check == 0)
8930                         /* this is the earliest that rebuild will be
8931                          * visible in /proc/mdstat
8932                          */
8933                         md_new_event(mddev);
8934
8935                 if (last_check + window > io_sectors || j == max_sectors)
8936                         continue;
8937
8938                 last_check = io_sectors;
8939         repeat:
8940                 if (time_after_eq(jiffies, mark[last_mark] + SYNC_MARK_STEP )) {
8941                         /* step marks */
8942                         int next = (last_mark+1) % SYNC_MARKS;
8943
8944                         mddev->resync_mark = mark[next];
8945                         mddev->resync_mark_cnt = mark_cnt[next];
8946                         mark[next] = jiffies;
8947                         mark_cnt[next] = io_sectors - atomic_read(&mddev->recovery_active);
8948                         last_mark = next;
8949                 }
8950
8951                 if (test_bit(MD_RECOVERY_INTR, &mddev->recovery))
8952                         break;
8953
8954                 /*
8955                  * this loop exits only if either when we are slower than
8956                  * the 'hard' speed limit, or the system was IO-idle for
8957                  * a jiffy.
8958                  * the system might be non-idle CPU-wise, but we only care
8959                  * about not overloading the IO subsystem. (things like an
8960                  * e2fsck being done on the RAID array should execute fast)
8961                  */
8962                 cond_resched();
8963
8964                 recovery_done = io_sectors - atomic_read(&mddev->recovery_active);
8965                 currspeed = ((unsigned long)(recovery_done - mddev->resync_mark_cnt))/2
8966                         /((jiffies-mddev->resync_mark)/HZ +1) +1;
8967
8968                 if (currspeed > speed_min(mddev)) {
8969                         if (currspeed > speed_max(mddev)) {
8970                                 msleep(500);
8971                                 goto repeat;
8972                         }
8973                         if (!is_mddev_idle(mddev, 0)) {
8974                                 /*
8975                                  * Give other IO more of a chance.
8976                                  * The faster the devices, the less we wait.
8977                                  */
8978                                 wait_event(mddev->recovery_wait,
8979                                            !atomic_read(&mddev->recovery_active));
8980                         }
8981                 }
8982         }
8983         pr_info("md: %s: %s %s.\n",mdname(mddev), desc,
8984                 test_bit(MD_RECOVERY_INTR, &mddev->recovery)
8985                 ? "interrupted" : "done");
8986         /*
8987          * this also signals 'finished resyncing' to md_stop
8988          */
8989         blk_finish_plug(&plug);
8990         wait_event(mddev->recovery_wait, !atomic_read(&mddev->recovery_active));
8991
8992         if (!test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery) &&
8993             !test_bit(MD_RECOVERY_INTR, &mddev->recovery) &&
8994             mddev->curr_resync > 3) {
8995                 mddev->curr_resync_completed = mddev->curr_resync;
8996                 sysfs_notify_dirent_safe(mddev->sysfs_completed);
8997         }
8998         mddev->pers->sync_request(mddev, max_sectors, &skipped);
8999
9000         if (!test_bit(MD_RECOVERY_CHECK, &mddev->recovery) &&
9001             mddev->curr_resync > 3) {
9002                 if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery)) {
9003                         if (test_bit(MD_RECOVERY_INTR, &mddev->recovery)) {
9004                                 if (mddev->curr_resync >= mddev->recovery_cp) {
9005                                         pr_debug("md: checkpointing %s of %s.\n",
9006                                                  desc, mdname(mddev));
9007                                         if (test_bit(MD_RECOVERY_ERROR,
9008                                                 &mddev->recovery))
9009                                                 mddev->recovery_cp =
9010                                                         mddev->curr_resync_completed;
9011                                         else
9012                                                 mddev->recovery_cp =
9013                                                         mddev->curr_resync;
9014                                 }
9015                         } else
9016                                 mddev->recovery_cp = MaxSector;
9017                 } else {
9018                         if (!test_bit(MD_RECOVERY_INTR, &mddev->recovery))
9019                                 mddev->curr_resync = MaxSector;
9020                         if (!test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery) &&
9021                             test_bit(MD_RECOVERY_RECOVER, &mddev->recovery)) {
9022                                 rcu_read_lock();
9023                                 rdev_for_each_rcu(rdev, mddev)
9024                                         if (rdev->raid_disk >= 0 &&
9025                                             mddev->delta_disks >= 0 &&
9026                                             !test_bit(Journal, &rdev->flags) &&
9027                                             !test_bit(Faulty, &rdev->flags) &&
9028                                             !test_bit(In_sync, &rdev->flags) &&
9029                                             rdev->recovery_offset < mddev->curr_resync)
9030                                                 rdev->recovery_offset = mddev->curr_resync;
9031                                 rcu_read_unlock();
9032                         }
9033                 }
9034         }
9035  skip:
9036         /* set CHANGE_PENDING here since maybe another update is needed,
9037          * so other nodes are informed. It should be harmless for normal
9038          * raid */
9039         set_mask_bits(&mddev->sb_flags, 0,
9040                       BIT(MD_SB_CHANGE_PENDING) | BIT(MD_SB_CHANGE_DEVS));
9041
9042         if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery) &&
9043                         !test_bit(MD_RECOVERY_INTR, &mddev->recovery) &&
9044                         mddev->delta_disks > 0 &&
9045                         mddev->pers->finish_reshape &&
9046                         mddev->pers->size &&
9047                         mddev->queue) {
9048                 mddev_lock_nointr(mddev);
9049                 md_set_array_sectors(mddev, mddev->pers->size(mddev, 0, 0));
9050                 mddev_unlock(mddev);
9051                 if (!mddev_is_clustered(mddev))
9052                         set_capacity_and_notify(mddev->gendisk,
9053                                                 mddev->array_sectors);
9054         }
9055
9056         spin_lock(&mddev->lock);
9057         if (!test_bit(MD_RECOVERY_INTR, &mddev->recovery)) {
9058                 /* We completed so min/max setting can be forgotten if used. */
9059                 if (test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery))
9060                         mddev->resync_min = 0;
9061                 mddev->resync_max = MaxSector;
9062         } else if (test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery))
9063                 mddev->resync_min = mddev->curr_resync_completed;
9064         set_bit(MD_RECOVERY_DONE, &mddev->recovery);
9065         mddev->curr_resync = 0;
9066         spin_unlock(&mddev->lock);
9067
9068         wake_up(&resync_wait);
9069         md_wakeup_thread(mddev->thread);
9070         return;
9071 }
9072 EXPORT_SYMBOL_GPL(md_do_sync);
9073
9074 static int remove_and_add_spares(struct mddev *mddev,
9075                                  struct md_rdev *this)
9076 {
9077         struct md_rdev *rdev;
9078         int spares = 0;
9079         int removed = 0;
9080         bool remove_some = false;
9081
9082         if (this && test_bit(MD_RECOVERY_RUNNING, &mddev->recovery))
9083                 /* Mustn't remove devices when resync thread is running */
9084                 return 0;
9085
9086         rdev_for_each(rdev, mddev) {
9087                 if ((this == NULL || rdev == this) &&
9088                     rdev->raid_disk >= 0 &&
9089                     !test_bit(Blocked, &rdev->flags) &&
9090                     test_bit(Faulty, &rdev->flags) &&
9091                     atomic_read(&rdev->nr_pending)==0) {
9092                         /* Faulty non-Blocked devices with nr_pending == 0
9093                          * never get nr_pending incremented,
9094                          * never get Faulty cleared, and never get Blocked set.
9095                          * So we can synchronize_rcu now rather than once per device
9096                          */
9097                         remove_some = true;
9098                         set_bit(RemoveSynchronized, &rdev->flags);
9099                 }
9100         }
9101
9102         if (remove_some)
9103                 synchronize_rcu();
9104         rdev_for_each(rdev, mddev) {
9105                 if ((this == NULL || rdev == this) &&
9106                     rdev->raid_disk >= 0 &&
9107                     !test_bit(Blocked, &rdev->flags) &&
9108                     ((test_bit(RemoveSynchronized, &rdev->flags) ||
9109                      (!test_bit(In_sync, &rdev->flags) &&
9110                       !test_bit(Journal, &rdev->flags))) &&
9111                     atomic_read(&rdev->nr_pending)==0)) {
9112                         if (mddev->pers->hot_remove_disk(
9113                                     mddev, rdev) == 0) {
9114                                 sysfs_unlink_rdev(mddev, rdev);
9115                                 rdev->saved_raid_disk = rdev->raid_disk;
9116                                 rdev->raid_disk = -1;
9117                                 removed++;
9118                         }
9119                 }
9120                 if (remove_some && test_bit(RemoveSynchronized, &rdev->flags))
9121                         clear_bit(RemoveSynchronized, &rdev->flags);
9122         }
9123
9124         if (removed && mddev->kobj.sd)
9125                 sysfs_notify_dirent_safe(mddev->sysfs_degraded);
9126
9127         if (this && removed)
9128                 goto no_add;
9129
9130         rdev_for_each(rdev, mddev) {
9131                 if (this && this != rdev)
9132                         continue;
9133                 if (test_bit(Candidate, &rdev->flags))
9134                         continue;
9135                 if (rdev->raid_disk >= 0 &&
9136                     !test_bit(In_sync, &rdev->flags) &&
9137                     !test_bit(Journal, &rdev->flags) &&
9138                     !test_bit(Faulty, &rdev->flags))
9139                         spares++;
9140                 if (rdev->raid_disk >= 0)
9141                         continue;
9142                 if (test_bit(Faulty, &rdev->flags))
9143                         continue;
9144                 if (!test_bit(Journal, &rdev->flags)) {
9145                         if (mddev->ro &&
9146                             ! (rdev->saved_raid_disk >= 0 &&
9147                                !test_bit(Bitmap_sync, &rdev->flags)))
9148                                 continue;
9149
9150                         rdev->recovery_offset = 0;
9151                 }
9152                 if (mddev->pers->hot_add_disk(mddev, rdev) == 0) {
9153                         /* failure here is OK */
9154                         sysfs_link_rdev(mddev, rdev);
9155                         if (!test_bit(Journal, &rdev->flags))
9156                                 spares++;
9157                         md_new_event(mddev);
9158                         set_bit(MD_SB_CHANGE_DEVS, &mddev->sb_flags);
9159                 }
9160         }
9161 no_add:
9162         if (removed)
9163                 set_bit(MD_SB_CHANGE_DEVS, &mddev->sb_flags);
9164         return spares;
9165 }
9166
9167 static void md_start_sync(struct work_struct *ws)
9168 {
9169         struct mddev *mddev = container_of(ws, struct mddev, del_work);
9170
9171         mddev->sync_thread = md_register_thread(md_do_sync,
9172                                                 mddev,
9173                                                 "resync");
9174         if (!mddev->sync_thread) {
9175                 pr_warn("%s: could not start resync thread...\n",
9176                         mdname(mddev));
9177                 /* leave the spares where they are, it shouldn't hurt */
9178                 clear_bit(MD_RECOVERY_SYNC, &mddev->recovery);
9179                 clear_bit(MD_RECOVERY_RESHAPE, &mddev->recovery);
9180                 clear_bit(MD_RECOVERY_REQUESTED, &mddev->recovery);
9181                 clear_bit(MD_RECOVERY_CHECK, &mddev->recovery);
9182                 clear_bit(MD_RECOVERY_RUNNING, &mddev->recovery);
9183                 wake_up(&resync_wait);
9184                 if (test_and_clear_bit(MD_RECOVERY_RECOVER,
9185                                        &mddev->recovery))
9186                         if (mddev->sysfs_action)
9187                                 sysfs_notify_dirent_safe(mddev->sysfs_action);
9188         } else
9189                 md_wakeup_thread(mddev->sync_thread);
9190         sysfs_notify_dirent_safe(mddev->sysfs_action);
9191         md_new_event(mddev);
9192 }
9193
9194 /*
9195  * This routine is regularly called by all per-raid-array threads to
9196  * deal with generic issues like resync and super-block update.
9197  * Raid personalities that don't have a thread (linear/raid0) do not
9198  * need this as they never do any recovery or update the superblock.
9199  *
9200  * It does not do any resync itself, but rather "forks" off other threads
9201  * to do that as needed.
9202  * When it is determined that resync is needed, we set MD_RECOVERY_RUNNING in
9203  * "->recovery" and create a thread at ->sync_thread.
9204  * When the thread finishes it sets MD_RECOVERY_DONE
9205  * and wakeups up this thread which will reap the thread and finish up.
9206  * This thread also removes any faulty devices (with nr_pending == 0).
9207  *
9208  * The overall approach is:
9209  *  1/ if the superblock needs updating, update it.
9210  *  2/ If a recovery thread is running, don't do anything else.
9211  *  3/ If recovery has finished, clean up, possibly marking spares active.
9212  *  4/ If there are any faulty devices, remove them.
9213  *  5/ If array is degraded, try to add spares devices
9214  *  6/ If array has spares or is not in-sync, start a resync thread.
9215  */
9216 void md_check_recovery(struct mddev *mddev)
9217 {
9218         if (test_bit(MD_ALLOW_SB_UPDATE, &mddev->flags) && mddev->sb_flags) {
9219                 /* Write superblock - thread that called mddev_suspend()
9220                  * holds reconfig_mutex for us.
9221                  */
9222                 set_bit(MD_UPDATING_SB, &mddev->flags);
9223                 smp_mb__after_atomic();
9224                 if (test_bit(MD_ALLOW_SB_UPDATE, &mddev->flags))
9225                         md_update_sb(mddev, 0);
9226                 clear_bit_unlock(MD_UPDATING_SB, &mddev->flags);
9227                 wake_up(&mddev->sb_wait);
9228         }
9229
9230         if (mddev->suspended)
9231                 return;
9232
9233         if (mddev->bitmap)
9234                 md_bitmap_daemon_work(mddev);
9235
9236         if (signal_pending(current)) {
9237                 if (mddev->pers->sync_request && !mddev->external) {
9238                         pr_debug("md: %s in immediate safe mode\n",
9239                                  mdname(mddev));
9240                         mddev->safemode = 2;
9241                 }
9242                 flush_signals(current);
9243         }
9244
9245         if (mddev->ro && !test_bit(MD_RECOVERY_NEEDED, &mddev->recovery))
9246                 return;
9247         if ( ! (
9248                 (mddev->sb_flags & ~ (1<<MD_SB_CHANGE_PENDING)) ||
9249                 test_bit(MD_RECOVERY_NEEDED, &mddev->recovery) ||
9250                 test_bit(MD_RECOVERY_DONE, &mddev->recovery) ||
9251                 (mddev->external == 0 && mddev->safemode == 1) ||
9252                 (mddev->safemode == 2
9253                  && !mddev->in_sync && mddev->recovery_cp == MaxSector)
9254                 ))
9255                 return;
9256
9257         if (mddev_trylock(mddev)) {
9258                 int spares = 0;
9259                 bool try_set_sync = mddev->safemode != 0;
9260
9261                 if (!mddev->external && mddev->safemode == 1)
9262                         mddev->safemode = 0;
9263
9264                 if (mddev->ro) {
9265                         struct md_rdev *rdev;
9266                         if (!mddev->external && mddev->in_sync)
9267                                 /* 'Blocked' flag not needed as failed devices
9268                                  * will be recorded if array switched to read/write.
9269                                  * Leaving it set will prevent the device
9270                                  * from being removed.
9271                                  */
9272                                 rdev_for_each(rdev, mddev)
9273                                         clear_bit(Blocked, &rdev->flags);
9274                         /* On a read-only array we can:
9275                          * - remove failed devices
9276                          * - add already-in_sync devices if the array itself
9277                          *   is in-sync.
9278                          * As we only add devices that are already in-sync,
9279                          * we can activate the spares immediately.
9280                          */
9281                         remove_and_add_spares(mddev, NULL);
9282                         /* There is no thread, but we need to call
9283                          * ->spare_active and clear saved_raid_disk
9284                          */
9285                         set_bit(MD_RECOVERY_INTR, &mddev->recovery);
9286                         md_reap_sync_thread(mddev);
9287                         clear_bit(MD_RECOVERY_RECOVER, &mddev->recovery);
9288                         clear_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
9289                         clear_bit(MD_SB_CHANGE_PENDING, &mddev->sb_flags);
9290                         goto unlock;
9291                 }
9292
9293                 if (mddev_is_clustered(mddev)) {
9294                         struct md_rdev *rdev, *tmp;
9295                         /* kick the device if another node issued a
9296                          * remove disk.
9297                          */
9298                         rdev_for_each_safe(rdev, tmp, mddev) {
9299                                 if (test_and_clear_bit(ClusterRemove, &rdev->flags) &&
9300                                                 rdev->raid_disk < 0)
9301                                         md_kick_rdev_from_array(rdev);
9302                         }
9303                 }
9304
9305                 if (try_set_sync && !mddev->external && !mddev->in_sync) {
9306                         spin_lock(&mddev->lock);
9307                         set_in_sync(mddev);
9308                         spin_unlock(&mddev->lock);
9309                 }
9310
9311                 if (mddev->sb_flags)
9312                         md_update_sb(mddev, 0);
9313
9314                 if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery) &&
9315                     !test_bit(MD_RECOVERY_DONE, &mddev->recovery)) {
9316                         /* resync/recovery still happening */
9317                         clear_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
9318                         goto unlock;
9319                 }
9320                 if (mddev->sync_thread) {
9321                         md_reap_sync_thread(mddev);
9322                         goto unlock;
9323                 }
9324                 /* Set RUNNING before clearing NEEDED to avoid
9325                  * any transients in the value of "sync_action".
9326                  */
9327                 mddev->curr_resync_completed = 0;
9328                 spin_lock(&mddev->lock);
9329                 set_bit(MD_RECOVERY_RUNNING, &mddev->recovery);
9330                 spin_unlock(&mddev->lock);
9331                 /* Clear some bits that don't mean anything, but
9332                  * might be left set
9333                  */
9334                 clear_bit(MD_RECOVERY_INTR, &mddev->recovery);
9335                 clear_bit(MD_RECOVERY_DONE, &mddev->recovery);
9336
9337                 if (!test_and_clear_bit(MD_RECOVERY_NEEDED, &mddev->recovery) ||
9338                     test_bit(MD_RECOVERY_FROZEN, &mddev->recovery))
9339                         goto not_running;
9340                 /* no recovery is running.
9341                  * remove any failed drives, then
9342                  * add spares if possible.
9343                  * Spares are also removed and re-added, to allow
9344                  * the personality to fail the re-add.
9345                  */
9346
9347                 if (mddev->reshape_position != MaxSector) {
9348                         if (mddev->pers->check_reshape == NULL ||
9349                             mddev->pers->check_reshape(mddev) != 0)
9350                                 /* Cannot proceed */
9351                                 goto not_running;
9352                         set_bit(MD_RECOVERY_RESHAPE, &mddev->recovery);
9353                         clear_bit(MD_RECOVERY_RECOVER, &mddev->recovery);
9354                 } else if ((spares = remove_and_add_spares(mddev, NULL))) {
9355                         clear_bit(MD_RECOVERY_SYNC, &mddev->recovery);
9356                         clear_bit(MD_RECOVERY_CHECK, &mddev->recovery);
9357                         clear_bit(MD_RECOVERY_REQUESTED, &mddev->recovery);
9358                         set_bit(MD_RECOVERY_RECOVER, &mddev->recovery);
9359                 } else if (mddev->recovery_cp < MaxSector) {
9360                         set_bit(MD_RECOVERY_SYNC, &mddev->recovery);
9361                         clear_bit(MD_RECOVERY_RECOVER, &mddev->recovery);
9362                 } else if (!test_bit(MD_RECOVERY_SYNC, &mddev->recovery))
9363                         /* nothing to be done ... */
9364                         goto not_running;
9365
9366                 if (mddev->pers->sync_request) {
9367                         if (spares) {
9368                                 /* We are adding a device or devices to an array
9369                                  * which has the bitmap stored on all devices.
9370                                  * So make sure all bitmap pages get written
9371                                  */
9372                                 md_bitmap_write_all(mddev->bitmap);
9373                         }
9374                         INIT_WORK(&mddev->del_work, md_start_sync);
9375                         queue_work(md_misc_wq, &mddev->del_work);
9376                         goto unlock;
9377                 }
9378         not_running:
9379                 if (!mddev->sync_thread) {
9380                         clear_bit(MD_RECOVERY_RUNNING, &mddev->recovery);
9381                         wake_up(&resync_wait);
9382                         if (test_and_clear_bit(MD_RECOVERY_RECOVER,
9383                                                &mddev->recovery))
9384                                 if (mddev->sysfs_action)
9385                                         sysfs_notify_dirent_safe(mddev->sysfs_action);
9386                 }
9387         unlock:
9388                 wake_up(&mddev->sb_wait);
9389                 mddev_unlock(mddev);
9390         }
9391 }
9392 EXPORT_SYMBOL(md_check_recovery);
9393
9394 void md_reap_sync_thread(struct mddev *mddev)
9395 {
9396         struct md_rdev *rdev;
9397         sector_t old_dev_sectors = mddev->dev_sectors;
9398         bool is_reshaped = false;
9399
9400         /* resync has finished, collect result */
9401         md_unregister_thread(&mddev->sync_thread);
9402         if (!test_bit(MD_RECOVERY_INTR, &mddev->recovery) &&
9403             !test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery) &&
9404             mddev->degraded != mddev->raid_disks) {
9405                 /* success...*/
9406                 /* activate any spares */
9407                 if (mddev->pers->spare_active(mddev)) {
9408                         sysfs_notify_dirent_safe(mddev->sysfs_degraded);
9409                         set_bit(MD_SB_CHANGE_DEVS, &mddev->sb_flags);
9410                 }
9411         }
9412         if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery) &&
9413             mddev->pers->finish_reshape) {
9414                 mddev->pers->finish_reshape(mddev);
9415                 if (mddev_is_clustered(mddev))
9416                         is_reshaped = true;
9417         }
9418
9419         /* If array is no-longer degraded, then any saved_raid_disk
9420          * information must be scrapped.
9421          */
9422         if (!mddev->degraded)
9423                 rdev_for_each(rdev, mddev)
9424                         rdev->saved_raid_disk = -1;
9425
9426         md_update_sb(mddev, 1);
9427         /* MD_SB_CHANGE_PENDING should be cleared by md_update_sb, so we can
9428          * call resync_finish here if MD_CLUSTER_RESYNC_LOCKED is set by
9429          * clustered raid */
9430         if (test_and_clear_bit(MD_CLUSTER_RESYNC_LOCKED, &mddev->flags))
9431                 md_cluster_ops->resync_finish(mddev);
9432         clear_bit(MD_RECOVERY_RUNNING, &mddev->recovery);
9433         clear_bit(MD_RECOVERY_DONE, &mddev->recovery);
9434         clear_bit(MD_RECOVERY_SYNC, &mddev->recovery);
9435         clear_bit(MD_RECOVERY_RESHAPE, &mddev->recovery);
9436         clear_bit(MD_RECOVERY_REQUESTED, &mddev->recovery);
9437         clear_bit(MD_RECOVERY_CHECK, &mddev->recovery);
9438         /*
9439          * We call md_cluster_ops->update_size here because sync_size could
9440          * be changed by md_update_sb, and MD_RECOVERY_RESHAPE is cleared,
9441          * so it is time to update size across cluster.
9442          */
9443         if (mddev_is_clustered(mddev) && is_reshaped
9444                                       && !test_bit(MD_CLOSING, &mddev->flags))
9445                 md_cluster_ops->update_size(mddev, old_dev_sectors);
9446         wake_up(&resync_wait);
9447         /* flag recovery needed just to double check */
9448         set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
9449         sysfs_notify_dirent_safe(mddev->sysfs_action);
9450         md_new_event(mddev);
9451         if (mddev->event_work.func)
9452                 queue_work(md_misc_wq, &mddev->event_work);
9453 }
9454 EXPORT_SYMBOL(md_reap_sync_thread);
9455
9456 void md_wait_for_blocked_rdev(struct md_rdev *rdev, struct mddev *mddev)
9457 {
9458         sysfs_notify_dirent_safe(rdev->sysfs_state);
9459         wait_event_timeout(rdev->blocked_wait,
9460                            !test_bit(Blocked, &rdev->flags) &&
9461                            !test_bit(BlockedBadBlocks, &rdev->flags),
9462                            msecs_to_jiffies(5000));
9463         rdev_dec_pending(rdev, mddev);
9464 }
9465 EXPORT_SYMBOL(md_wait_for_blocked_rdev);
9466
9467 void md_finish_reshape(struct mddev *mddev)
9468 {
9469         /* called be personality module when reshape completes. */
9470         struct md_rdev *rdev;
9471
9472         rdev_for_each(rdev, mddev) {
9473                 if (rdev->data_offset > rdev->new_data_offset)
9474                         rdev->sectors += rdev->data_offset - rdev->new_data_offset;
9475                 else
9476                         rdev->sectors -= rdev->new_data_offset - rdev->data_offset;
9477                 rdev->data_offset = rdev->new_data_offset;
9478         }
9479 }
9480 EXPORT_SYMBOL(md_finish_reshape);
9481
9482 /* Bad block management */
9483
9484 /* Returns 1 on success, 0 on failure */
9485 int rdev_set_badblocks(struct md_rdev *rdev, sector_t s, int sectors,
9486                        int is_new)
9487 {
9488         struct mddev *mddev = rdev->mddev;
9489         int rv;
9490         if (is_new)
9491                 s += rdev->new_data_offset;
9492         else
9493                 s += rdev->data_offset;
9494         rv = badblocks_set(&rdev->badblocks, s, sectors, 0);
9495         if (rv == 0) {
9496                 /* Make sure they get written out promptly */
9497                 if (test_bit(ExternalBbl, &rdev->flags))
9498                         sysfs_notify_dirent_safe(rdev->sysfs_unack_badblocks);
9499                 sysfs_notify_dirent_safe(rdev->sysfs_state);
9500                 set_mask_bits(&mddev->sb_flags, 0,
9501                               BIT(MD_SB_CHANGE_CLEAN) | BIT(MD_SB_CHANGE_PENDING));
9502                 md_wakeup_thread(rdev->mddev->thread);
9503                 return 1;
9504         } else
9505                 return 0;
9506 }
9507 EXPORT_SYMBOL_GPL(rdev_set_badblocks);
9508
9509 int rdev_clear_badblocks(struct md_rdev *rdev, sector_t s, int sectors,
9510                          int is_new)
9511 {
9512         int rv;
9513         if (is_new)
9514                 s += rdev->new_data_offset;
9515         else
9516                 s += rdev->data_offset;
9517         rv = badblocks_clear(&rdev->badblocks, s, sectors);
9518         if ((rv == 0) && test_bit(ExternalBbl, &rdev->flags))
9519                 sysfs_notify_dirent_safe(rdev->sysfs_badblocks);
9520         return rv;
9521 }
9522 EXPORT_SYMBOL_GPL(rdev_clear_badblocks);
9523
9524 static int md_notify_reboot(struct notifier_block *this,
9525                             unsigned long code, void *x)
9526 {
9527         struct list_head *tmp;
9528         struct mddev *mddev;
9529         int need_delay = 0;
9530
9531         for_each_mddev(mddev, tmp) {
9532                 if (mddev_trylock(mddev)) {
9533                         if (mddev->pers)
9534                                 __md_stop_writes(mddev);
9535                         if (mddev->persistent)
9536                                 mddev->safemode = 2;
9537                         mddev_unlock(mddev);
9538                 }
9539                 need_delay = 1;
9540         }
9541         /*
9542          * certain more exotic SCSI devices are known to be
9543          * volatile wrt too early system reboots. While the
9544          * right place to handle this issue is the given
9545          * driver, we do want to have a safe RAID driver ...
9546          */
9547         if (need_delay)
9548                 mdelay(1000*1);
9549
9550         return NOTIFY_DONE;
9551 }
9552
9553 static struct notifier_block md_notifier = {
9554         .notifier_call  = md_notify_reboot,
9555         .next           = NULL,
9556         .priority       = INT_MAX, /* before any real devices */
9557 };
9558
9559 static void md_geninit(void)
9560 {
9561         pr_debug("md: sizeof(mdp_super_t) = %d\n", (int)sizeof(mdp_super_t));
9562
9563         proc_create("mdstat", S_IRUGO, NULL, &mdstat_proc_ops);
9564 }
9565
9566 static int __init md_init(void)
9567 {
9568         int ret = -ENOMEM;
9569
9570         md_wq = alloc_workqueue("md", WQ_MEM_RECLAIM, 0);
9571         if (!md_wq)
9572                 goto err_wq;
9573
9574         md_misc_wq = alloc_workqueue("md_misc", 0, 0);
9575         if (!md_misc_wq)
9576                 goto err_misc_wq;
9577
9578         md_rdev_misc_wq = alloc_workqueue("md_rdev_misc", 0, 0);
9579         if (!md_rdev_misc_wq)
9580                 goto err_rdev_misc_wq;
9581
9582         ret = __register_blkdev(MD_MAJOR, "md", md_probe);
9583         if (ret < 0)
9584                 goto err_md;
9585
9586         ret = __register_blkdev(0, "mdp", md_probe);
9587         if (ret < 0)
9588                 goto err_mdp;
9589         mdp_major = ret;
9590
9591         register_reboot_notifier(&md_notifier);
9592         raid_table_header = register_sysctl_table(raid_root_table);
9593
9594         md_geninit();
9595         return 0;
9596
9597 err_mdp:
9598         unregister_blkdev(MD_MAJOR, "md");
9599 err_md:
9600         destroy_workqueue(md_rdev_misc_wq);
9601 err_rdev_misc_wq:
9602         destroy_workqueue(md_misc_wq);
9603 err_misc_wq:
9604         destroy_workqueue(md_wq);
9605 err_wq:
9606         return ret;
9607 }
9608
9609 static void check_sb_changes(struct mddev *mddev, struct md_rdev *rdev)
9610 {
9611         struct mdp_superblock_1 *sb = page_address(rdev->sb_page);
9612         struct md_rdev *rdev2, *tmp;
9613         int role, ret;
9614         char b[BDEVNAME_SIZE];
9615
9616         /*
9617          * If size is changed in another node then we need to
9618          * do resize as well.
9619          */
9620         if (mddev->dev_sectors != le64_to_cpu(sb->size)) {
9621                 ret = mddev->pers->resize(mddev, le64_to_cpu(sb->size));
9622                 if (ret)
9623                         pr_info("md-cluster: resize failed\n");
9624                 else
9625                         md_bitmap_update_sb(mddev->bitmap);
9626         }
9627
9628         /* Check for change of roles in the active devices */
9629         rdev_for_each_safe(rdev2, tmp, mddev) {
9630                 if (test_bit(Faulty, &rdev2->flags))
9631                         continue;
9632
9633                 /* Check if the roles changed */
9634                 role = le16_to_cpu(sb->dev_roles[rdev2->desc_nr]);
9635
9636                 if (test_bit(Candidate, &rdev2->flags)) {
9637                         if (role == 0xfffe) {
9638                                 pr_info("md: Removing Candidate device %s because add failed\n", bdevname(rdev2->bdev,b));
9639                                 md_kick_rdev_from_array(rdev2);
9640                                 continue;
9641                         }
9642                         else
9643                                 clear_bit(Candidate, &rdev2->flags);
9644                 }
9645
9646                 if (role != rdev2->raid_disk) {
9647                         /*
9648                          * got activated except reshape is happening.
9649                          */
9650                         if (rdev2->raid_disk == -1 && role != 0xffff &&
9651                             !(le32_to_cpu(sb->feature_map) &
9652                               MD_FEATURE_RESHAPE_ACTIVE)) {
9653                                 rdev2->saved_raid_disk = role;
9654                                 ret = remove_and_add_spares(mddev, rdev2);
9655                                 pr_info("Activated spare: %s\n",
9656                                         bdevname(rdev2->bdev,b));
9657                                 /* wakeup mddev->thread here, so array could
9658                                  * perform resync with the new activated disk */
9659                                 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
9660                                 md_wakeup_thread(mddev->thread);
9661                         }
9662                         /* device faulty
9663                          * We just want to do the minimum to mark the disk
9664                          * as faulty. The recovery is performed by the
9665                          * one who initiated the error.
9666                          */
9667                         if ((role == 0xfffe) || (role == 0xfffd)) {
9668                                 md_error(mddev, rdev2);
9669                                 clear_bit(Blocked, &rdev2->flags);
9670                         }
9671                 }
9672         }
9673
9674         if (mddev->raid_disks != le32_to_cpu(sb->raid_disks)) {
9675                 ret = update_raid_disks(mddev, le32_to_cpu(sb->raid_disks));
9676                 if (ret)
9677                         pr_warn("md: updating array disks failed. %d\n", ret);
9678         }
9679
9680         /*
9681          * Since mddev->delta_disks has already updated in update_raid_disks,
9682          * so it is time to check reshape.
9683          */
9684         if (test_bit(MD_RESYNCING_REMOTE, &mddev->recovery) &&
9685             (le32_to_cpu(sb->feature_map) & MD_FEATURE_RESHAPE_ACTIVE)) {
9686                 /*
9687                  * reshape is happening in the remote node, we need to
9688                  * update reshape_position and call start_reshape.
9689                  */
9690                 mddev->reshape_position = le64_to_cpu(sb->reshape_position);
9691                 if (mddev->pers->update_reshape_pos)
9692                         mddev->pers->update_reshape_pos(mddev);
9693                 if (mddev->pers->start_reshape)
9694                         mddev->pers->start_reshape(mddev);
9695         } else if (test_bit(MD_RESYNCING_REMOTE, &mddev->recovery) &&
9696                    mddev->reshape_position != MaxSector &&
9697                    !(le32_to_cpu(sb->feature_map) & MD_FEATURE_RESHAPE_ACTIVE)) {
9698                 /* reshape is just done in another node. */
9699                 mddev->reshape_position = MaxSector;
9700                 if (mddev->pers->update_reshape_pos)
9701                         mddev->pers->update_reshape_pos(mddev);
9702         }
9703
9704         /* Finally set the event to be up to date */
9705         mddev->events = le64_to_cpu(sb->events);
9706 }
9707
9708 static int read_rdev(struct mddev *mddev, struct md_rdev *rdev)
9709 {
9710         int err;
9711         struct page *swapout = rdev->sb_page;
9712         struct mdp_superblock_1 *sb;
9713
9714         /* Store the sb page of the rdev in the swapout temporary
9715          * variable in case we err in the future
9716          */
9717         rdev->sb_page = NULL;
9718         err = alloc_disk_sb(rdev);
9719         if (err == 0) {
9720                 ClearPageUptodate(rdev->sb_page);
9721                 rdev->sb_loaded = 0;
9722                 err = super_types[mddev->major_version].
9723                         load_super(rdev, NULL, mddev->minor_version);
9724         }
9725         if (err < 0) {
9726                 pr_warn("%s: %d Could not reload rdev(%d) err: %d. Restoring old values\n",
9727                                 __func__, __LINE__, rdev->desc_nr, err);
9728                 if (rdev->sb_page)
9729                         put_page(rdev->sb_page);
9730                 rdev->sb_page = swapout;
9731                 rdev->sb_loaded = 1;
9732                 return err;
9733         }
9734
9735         sb = page_address(rdev->sb_page);
9736         /* Read the offset unconditionally, even if MD_FEATURE_RECOVERY_OFFSET
9737          * is not set
9738          */
9739
9740         if ((le32_to_cpu(sb->feature_map) & MD_FEATURE_RECOVERY_OFFSET))
9741                 rdev->recovery_offset = le64_to_cpu(sb->recovery_offset);
9742
9743         /* The other node finished recovery, call spare_active to set
9744          * device In_sync and mddev->degraded
9745          */
9746         if (rdev->recovery_offset == MaxSector &&
9747             !test_bit(In_sync, &rdev->flags) &&
9748             mddev->pers->spare_active(mddev))
9749                 sysfs_notify_dirent_safe(mddev->sysfs_degraded);
9750
9751         put_page(swapout);
9752         return 0;
9753 }
9754
9755 void md_reload_sb(struct mddev *mddev, int nr)
9756 {
9757         struct md_rdev *rdev;
9758         int err;
9759
9760         /* Find the rdev */
9761         rdev_for_each_rcu(rdev, mddev) {
9762                 if (rdev->desc_nr == nr)
9763                         break;
9764         }
9765
9766         if (!rdev || rdev->desc_nr != nr) {
9767                 pr_warn("%s: %d Could not find rdev with nr %d\n", __func__, __LINE__, nr);
9768                 return;
9769         }
9770
9771         err = read_rdev(mddev, rdev);
9772         if (err < 0)
9773                 return;
9774
9775         check_sb_changes(mddev, rdev);
9776
9777         /* Read all rdev's to update recovery_offset */
9778         rdev_for_each_rcu(rdev, mddev) {
9779                 if (!test_bit(Faulty, &rdev->flags))
9780                         read_rdev(mddev, rdev);
9781         }
9782 }
9783 EXPORT_SYMBOL(md_reload_sb);
9784
9785 #ifndef MODULE
9786
9787 /*
9788  * Searches all registered partitions for autorun RAID arrays
9789  * at boot time.
9790  */
9791
9792 static DEFINE_MUTEX(detected_devices_mutex);
9793 static LIST_HEAD(all_detected_devices);
9794 struct detected_devices_node {
9795         struct list_head list;
9796         dev_t dev;
9797 };
9798
9799 void md_autodetect_dev(dev_t dev)
9800 {
9801         struct detected_devices_node *node_detected_dev;
9802
9803         node_detected_dev = kzalloc(sizeof(*node_detected_dev), GFP_KERNEL);
9804         if (node_detected_dev) {
9805                 node_detected_dev->dev = dev;
9806                 mutex_lock(&detected_devices_mutex);
9807                 list_add_tail(&node_detected_dev->list, &all_detected_devices);
9808                 mutex_unlock(&detected_devices_mutex);
9809         }
9810 }
9811
9812 void md_autostart_arrays(int part)
9813 {
9814         struct md_rdev *rdev;
9815         struct detected_devices_node *node_detected_dev;
9816         dev_t dev;
9817         int i_scanned, i_passed;
9818
9819         i_scanned = 0;
9820         i_passed = 0;
9821
9822         pr_info("md: Autodetecting RAID arrays.\n");
9823
9824         mutex_lock(&detected_devices_mutex);
9825         while (!list_empty(&all_detected_devices) && i_scanned < INT_MAX) {
9826                 i_scanned++;
9827                 node_detected_dev = list_entry(all_detected_devices.next,
9828                                         struct detected_devices_node, list);
9829                 list_del(&node_detected_dev->list);
9830                 dev = node_detected_dev->dev;
9831                 kfree(node_detected_dev);
9832                 mutex_unlock(&detected_devices_mutex);
9833                 rdev = md_import_device(dev,0, 90);
9834                 mutex_lock(&detected_devices_mutex);
9835                 if (IS_ERR(rdev))
9836                         continue;
9837
9838                 if (test_bit(Faulty, &rdev->flags))
9839                         continue;
9840
9841                 set_bit(AutoDetected, &rdev->flags);
9842                 list_add(&rdev->same_set, &pending_raid_disks);
9843                 i_passed++;
9844         }
9845         mutex_unlock(&detected_devices_mutex);
9846
9847         pr_debug("md: Scanned %d and added %d devices.\n", i_scanned, i_passed);
9848
9849         autorun_devices(part);
9850 }
9851
9852 #endif /* !MODULE */
9853
9854 static __exit void md_exit(void)
9855 {
9856         struct mddev *mddev;
9857         struct list_head *tmp;
9858         int delay = 1;
9859
9860         unregister_blkdev(MD_MAJOR,"md");
9861         unregister_blkdev(mdp_major, "mdp");
9862         unregister_reboot_notifier(&md_notifier);
9863         unregister_sysctl_table(raid_table_header);
9864
9865         /* We cannot unload the modules while some process is
9866          * waiting for us in select() or poll() - wake them up
9867          */
9868         md_unloading = 1;
9869         while (waitqueue_active(&md_event_waiters)) {
9870                 /* not safe to leave yet */
9871                 wake_up(&md_event_waiters);
9872                 msleep(delay);
9873                 delay += delay;
9874         }
9875         remove_proc_entry("mdstat", NULL);
9876
9877         for_each_mddev(mddev, tmp) {
9878                 export_array(mddev);
9879                 mddev->ctime = 0;
9880                 mddev->hold_active = 0;
9881                 /*
9882                  * for_each_mddev() will call mddev_put() at the end of each
9883                  * iteration.  As the mddev is now fully clear, this will
9884                  * schedule the mddev for destruction by a workqueue, and the
9885                  * destroy_workqueue() below will wait for that to complete.
9886                  */
9887         }
9888         destroy_workqueue(md_rdev_misc_wq);
9889         destroy_workqueue(md_misc_wq);
9890         destroy_workqueue(md_wq);
9891 }
9892
9893 subsys_initcall(md_init);
9894 module_exit(md_exit)
9895
9896 static int get_ro(char *buffer, const struct kernel_param *kp)
9897 {
9898         return sprintf(buffer, "%d\n", start_readonly);
9899 }
9900 static int set_ro(const char *val, const struct kernel_param *kp)
9901 {
9902         return kstrtouint(val, 10, (unsigned int *)&start_readonly);
9903 }
9904
9905 module_param_call(start_ro, set_ro, get_ro, NULL, S_IRUSR|S_IWUSR);
9906 module_param(start_dirty_degraded, int, S_IRUGO|S_IWUSR);
9907 module_param_call(new_array, add_named_array, NULL, NULL, S_IWUSR);
9908 module_param(create_on_open, bool, S_IRUSR|S_IWUSR);
9909
9910 MODULE_LICENSE("GPL");
9911 MODULE_DESCRIPTION("MD RAID framework");
9912 MODULE_ALIAS("md");
9913 MODULE_ALIAS_BLOCKDEV_MAJOR(MD_MAJOR);