1 // SPDX-License-Identifier: GPL-2.0
3 * Copyright (C) STRATO AG 2012. All rights reserved.
6 #include <linux/sched.h>
8 #include <linux/slab.h>
9 #include <linux/blkdev.h>
10 #include <linux/kthread.h>
11 #include <linux/math64.h>
13 #include "extent_map.h"
15 #include "transaction.h"
16 #include "print-tree.h"
18 #include "async-thread.h"
19 #include "check-integrity.h"
20 #include "rcu-string.h"
21 #include "dev-replace.h"
24 static int btrfs_dev_replace_finishing(struct btrfs_fs_info *fs_info,
26 static void btrfs_dev_replace_update_device_in_mapping_tree(
27 struct btrfs_fs_info *fs_info,
28 struct btrfs_device *srcdev,
29 struct btrfs_device *tgtdev);
30 static int btrfs_dev_replace_kthread(void *data);
32 int btrfs_init_dev_replace(struct btrfs_fs_info *fs_info)
35 struct btrfs_root *dev_root = fs_info->dev_root;
36 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace;
37 struct extent_buffer *eb;
40 struct btrfs_path *path = NULL;
42 struct btrfs_dev_replace_item *ptr;
45 path = btrfs_alloc_path();
52 key.type = BTRFS_DEV_REPLACE_KEY;
54 ret = btrfs_search_slot(NULL, dev_root, &key, path, 0, 0);
56 no_valid_dev_replace_entry_found:
58 dev_replace->replace_state =
59 BTRFS_DEV_REPLACE_ITEM_STATE_NEVER_STARTED;
60 dev_replace->cont_reading_from_srcdev_mode =
61 BTRFS_DEV_REPLACE_ITEM_CONT_READING_FROM_SRCDEV_MODE_ALWAYS;
62 dev_replace->replace_state = 0;
63 dev_replace->time_started = 0;
64 dev_replace->time_stopped = 0;
65 atomic64_set(&dev_replace->num_write_errors, 0);
66 atomic64_set(&dev_replace->num_uncorrectable_read_errors, 0);
67 dev_replace->cursor_left = 0;
68 dev_replace->committed_cursor_left = 0;
69 dev_replace->cursor_left_last_write_of_item = 0;
70 dev_replace->cursor_right = 0;
71 dev_replace->srcdev = NULL;
72 dev_replace->tgtdev = NULL;
73 dev_replace->is_valid = 0;
74 dev_replace->item_needs_writeback = 0;
77 slot = path->slots[0];
79 item_size = btrfs_item_size_nr(eb, slot);
80 ptr = btrfs_item_ptr(eb, slot, struct btrfs_dev_replace_item);
82 if (item_size != sizeof(struct btrfs_dev_replace_item)) {
84 "dev_replace entry found has unexpected size, ignore entry");
85 goto no_valid_dev_replace_entry_found;
88 src_devid = btrfs_dev_replace_src_devid(eb, ptr);
89 dev_replace->cont_reading_from_srcdev_mode =
90 btrfs_dev_replace_cont_reading_from_srcdev_mode(eb, ptr);
91 dev_replace->replace_state = btrfs_dev_replace_replace_state(eb, ptr);
92 dev_replace->time_started = btrfs_dev_replace_time_started(eb, ptr);
93 dev_replace->time_stopped =
94 btrfs_dev_replace_time_stopped(eb, ptr);
95 atomic64_set(&dev_replace->num_write_errors,
96 btrfs_dev_replace_num_write_errors(eb, ptr));
97 atomic64_set(&dev_replace->num_uncorrectable_read_errors,
98 btrfs_dev_replace_num_uncorrectable_read_errors(eb, ptr));
99 dev_replace->cursor_left = btrfs_dev_replace_cursor_left(eb, ptr);
100 dev_replace->committed_cursor_left = dev_replace->cursor_left;
101 dev_replace->cursor_left_last_write_of_item = dev_replace->cursor_left;
102 dev_replace->cursor_right = btrfs_dev_replace_cursor_right(eb, ptr);
103 dev_replace->is_valid = 1;
105 dev_replace->item_needs_writeback = 0;
106 switch (dev_replace->replace_state) {
107 case BTRFS_IOCTL_DEV_REPLACE_STATE_NEVER_STARTED:
108 case BTRFS_IOCTL_DEV_REPLACE_STATE_FINISHED:
109 case BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED:
110 dev_replace->srcdev = NULL;
111 dev_replace->tgtdev = NULL;
113 case BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED:
114 case BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED:
115 dev_replace->srcdev = btrfs_find_device(fs_info, src_devid,
117 dev_replace->tgtdev = btrfs_find_device(fs_info,
118 BTRFS_DEV_REPLACE_DEVID,
121 * allow 'btrfs dev replace_cancel' if src/tgt device is
124 if (!dev_replace->srcdev &&
125 !btrfs_test_opt(fs_info, DEGRADED)) {
128 "cannot mount because device replace operation is ongoing and");
130 "srcdev (devid %llu) is missing, need to run 'btrfs dev scan'?",
133 if (!dev_replace->tgtdev &&
134 !btrfs_test_opt(fs_info, DEGRADED)) {
137 "cannot mount because device replace operation is ongoing and");
139 "tgtdev (devid %llu) is missing, need to run 'btrfs dev scan'?",
140 BTRFS_DEV_REPLACE_DEVID);
142 if (dev_replace->tgtdev) {
143 if (dev_replace->srcdev) {
144 dev_replace->tgtdev->total_bytes =
145 dev_replace->srcdev->total_bytes;
146 dev_replace->tgtdev->disk_total_bytes =
147 dev_replace->srcdev->disk_total_bytes;
148 dev_replace->tgtdev->commit_total_bytes =
149 dev_replace->srcdev->commit_total_bytes;
150 dev_replace->tgtdev->bytes_used =
151 dev_replace->srcdev->bytes_used;
152 dev_replace->tgtdev->commit_bytes_used =
153 dev_replace->srcdev->commit_bytes_used;
155 set_bit(BTRFS_DEV_STATE_REPLACE_TGT,
156 &dev_replace->tgtdev->dev_state);
158 WARN_ON(fs_info->fs_devices->rw_devices == 0);
159 dev_replace->tgtdev->io_width = fs_info->sectorsize;
160 dev_replace->tgtdev->io_align = fs_info->sectorsize;
161 dev_replace->tgtdev->sector_size = fs_info->sectorsize;
162 dev_replace->tgtdev->fs_info = fs_info;
163 set_bit(BTRFS_DEV_STATE_IN_FS_METADATA,
164 &dev_replace->tgtdev->dev_state);
170 btrfs_free_path(path);
175 * Initialize a new device for device replace target from a given source dev
178 * Return 0 and new device in @device_out, otherwise return < 0
180 static int btrfs_init_dev_replace_tgtdev(struct btrfs_fs_info *fs_info,
181 const char *device_path,
182 struct btrfs_device *srcdev,
183 struct btrfs_device **device_out)
185 struct btrfs_device *device;
186 struct block_device *bdev;
187 struct list_head *devices;
188 struct rcu_string *name;
189 u64 devid = BTRFS_DEV_REPLACE_DEVID;
193 if (fs_info->fs_devices->seeding) {
194 btrfs_err(fs_info, "the filesystem is a seed filesystem!");
198 bdev = blkdev_get_by_path(device_path, FMODE_WRITE | FMODE_EXCL,
199 fs_info->bdev_holder);
201 btrfs_err(fs_info, "target device %s is invalid!", device_path);
202 return PTR_ERR(bdev);
205 filemap_write_and_wait(bdev->bd_inode->i_mapping);
207 devices = &fs_info->fs_devices->devices;
208 list_for_each_entry(device, devices, dev_list) {
209 if (device->bdev == bdev) {
211 "target device is in the filesystem!");
218 if (i_size_read(bdev->bd_inode) <
219 btrfs_device_get_total_bytes(srcdev)) {
221 "target device is smaller than source device!");
227 device = btrfs_alloc_device(NULL, &devid, NULL);
228 if (IS_ERR(device)) {
229 ret = PTR_ERR(device);
233 name = rcu_string_strdup(device_path, GFP_KERNEL);
235 btrfs_free_device(device);
239 rcu_assign_pointer(device->name, name);
241 mutex_lock(&fs_info->fs_devices->device_list_mutex);
242 set_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state);
243 device->generation = 0;
244 device->io_width = fs_info->sectorsize;
245 device->io_align = fs_info->sectorsize;
246 device->sector_size = fs_info->sectorsize;
247 device->total_bytes = btrfs_device_get_total_bytes(srcdev);
248 device->disk_total_bytes = btrfs_device_get_disk_total_bytes(srcdev);
249 device->bytes_used = btrfs_device_get_bytes_used(srcdev);
250 device->commit_total_bytes = srcdev->commit_total_bytes;
251 device->commit_bytes_used = device->bytes_used;
252 device->fs_info = fs_info;
254 set_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &device->dev_state);
255 set_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state);
256 device->mode = FMODE_EXCL;
257 device->dev_stats_valid = 1;
258 set_blocksize(device->bdev, BTRFS_BDEV_BLOCKSIZE);
259 device->fs_devices = fs_info->fs_devices;
260 list_add(&device->dev_list, &fs_info->fs_devices->devices);
261 fs_info->fs_devices->num_devices++;
262 fs_info->fs_devices->open_devices++;
263 mutex_unlock(&fs_info->fs_devices->device_list_mutex);
265 *device_out = device;
269 blkdev_put(bdev, FMODE_EXCL);
274 * called from commit_transaction. Writes changed device replace state to
277 int btrfs_run_dev_replace(struct btrfs_trans_handle *trans,
278 struct btrfs_fs_info *fs_info)
281 struct btrfs_root *dev_root = fs_info->dev_root;
282 struct btrfs_path *path;
283 struct btrfs_key key;
284 struct extent_buffer *eb;
285 struct btrfs_dev_replace_item *ptr;
286 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace;
288 btrfs_dev_replace_read_lock(dev_replace);
289 if (!dev_replace->is_valid ||
290 !dev_replace->item_needs_writeback) {
291 btrfs_dev_replace_read_unlock(dev_replace);
294 btrfs_dev_replace_read_unlock(dev_replace);
297 key.type = BTRFS_DEV_REPLACE_KEY;
300 path = btrfs_alloc_path();
305 ret = btrfs_search_slot(trans, dev_root, &key, path, -1, 1);
308 "error %d while searching for dev_replace item!",
314 btrfs_item_size_nr(path->nodes[0], path->slots[0]) < sizeof(*ptr)) {
316 * need to delete old one and insert a new one.
317 * Since no attempt is made to recover any old state, if the
318 * dev_replace state is 'running', the data on the target
320 * It would be possible to recover the state: just make sure
321 * that the beginning of the item is never changed and always
322 * contains all the essential information. Then read this
323 * minimal set of information and use it as a base for the
326 ret = btrfs_del_item(trans, dev_root, path);
329 "delete too small dev_replace item failed %d!",
337 /* need to insert a new item */
338 btrfs_release_path(path);
339 ret = btrfs_insert_empty_item(trans, dev_root, path,
343 "insert dev_replace item failed %d!", ret);
349 ptr = btrfs_item_ptr(eb, path->slots[0],
350 struct btrfs_dev_replace_item);
352 btrfs_dev_replace_write_lock(dev_replace);
353 if (dev_replace->srcdev)
354 btrfs_set_dev_replace_src_devid(eb, ptr,
355 dev_replace->srcdev->devid);
357 btrfs_set_dev_replace_src_devid(eb, ptr, (u64)-1);
358 btrfs_set_dev_replace_cont_reading_from_srcdev_mode(eb, ptr,
359 dev_replace->cont_reading_from_srcdev_mode);
360 btrfs_set_dev_replace_replace_state(eb, ptr,
361 dev_replace->replace_state);
362 btrfs_set_dev_replace_time_started(eb, ptr, dev_replace->time_started);
363 btrfs_set_dev_replace_time_stopped(eb, ptr, dev_replace->time_stopped);
364 btrfs_set_dev_replace_num_write_errors(eb, ptr,
365 atomic64_read(&dev_replace->num_write_errors));
366 btrfs_set_dev_replace_num_uncorrectable_read_errors(eb, ptr,
367 atomic64_read(&dev_replace->num_uncorrectable_read_errors));
368 dev_replace->cursor_left_last_write_of_item =
369 dev_replace->cursor_left;
370 btrfs_set_dev_replace_cursor_left(eb, ptr,
371 dev_replace->cursor_left_last_write_of_item);
372 btrfs_set_dev_replace_cursor_right(eb, ptr,
373 dev_replace->cursor_right);
374 dev_replace->item_needs_writeback = 0;
375 btrfs_dev_replace_write_unlock(dev_replace);
377 btrfs_mark_buffer_dirty(eb);
380 btrfs_free_path(path);
385 void btrfs_after_dev_replace_commit(struct btrfs_fs_info *fs_info)
387 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace;
389 dev_replace->committed_cursor_left =
390 dev_replace->cursor_left_last_write_of_item;
393 static char* btrfs_dev_name(struct btrfs_device *device)
395 if (!device || test_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state))
396 return "<missing disk>";
398 return rcu_str_deref(device->name);
401 int btrfs_dev_replace_start(struct btrfs_fs_info *fs_info,
402 const char *tgtdev_name, u64 srcdevid, const char *srcdev_name,
405 struct btrfs_root *root = fs_info->dev_root;
406 struct btrfs_trans_handle *trans;
407 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace;
409 struct btrfs_device *tgt_device = NULL;
410 struct btrfs_device *src_device = NULL;
412 ret = btrfs_find_device_by_devspec(fs_info, srcdevid,
413 srcdev_name, &src_device);
417 ret = btrfs_init_dev_replace_tgtdev(fs_info, tgtdev_name,
418 src_device, &tgt_device);
423 * Here we commit the transaction to make sure commit_total_bytes
424 * of all the devices are updated.
426 trans = btrfs_attach_transaction(root);
427 if (!IS_ERR(trans)) {
428 ret = btrfs_commit_transaction(trans);
431 } else if (PTR_ERR(trans) != -ENOENT) {
432 return PTR_ERR(trans);
435 btrfs_dev_replace_write_lock(dev_replace);
436 switch (dev_replace->replace_state) {
437 case BTRFS_IOCTL_DEV_REPLACE_STATE_NEVER_STARTED:
438 case BTRFS_IOCTL_DEV_REPLACE_STATE_FINISHED:
439 case BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED:
441 case BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED:
442 case BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED:
443 ret = BTRFS_IOCTL_DEV_REPLACE_RESULT_ALREADY_STARTED;
447 dev_replace->cont_reading_from_srcdev_mode = read_src;
448 WARN_ON(!src_device);
449 dev_replace->srcdev = src_device;
450 dev_replace->tgtdev = tgt_device;
452 btrfs_info_in_rcu(fs_info,
453 "dev_replace from %s (devid %llu) to %s started",
454 btrfs_dev_name(src_device),
456 rcu_str_deref(tgt_device->name));
459 * from now on, the writes to the srcdev are all duplicated to
460 * go to the tgtdev as well (refer to btrfs_map_block()).
462 dev_replace->replace_state = BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED;
463 dev_replace->time_started = ktime_get_real_seconds();
464 dev_replace->cursor_left = 0;
465 dev_replace->committed_cursor_left = 0;
466 dev_replace->cursor_left_last_write_of_item = 0;
467 dev_replace->cursor_right = 0;
468 dev_replace->is_valid = 1;
469 dev_replace->item_needs_writeback = 1;
470 atomic64_set(&dev_replace->num_write_errors, 0);
471 atomic64_set(&dev_replace->num_uncorrectable_read_errors, 0);
472 btrfs_dev_replace_write_unlock(dev_replace);
474 ret = btrfs_sysfs_add_device_link(tgt_device->fs_devices, tgt_device);
476 btrfs_err(fs_info, "kobj add dev failed %d", ret);
478 btrfs_wait_ordered_roots(fs_info, U64_MAX, 0, (u64)-1);
480 /* force writing the updated state information to disk */
481 trans = btrfs_start_transaction(root, 0);
483 ret = PTR_ERR(trans);
484 btrfs_dev_replace_write_lock(dev_replace);
488 ret = btrfs_commit_transaction(trans);
491 /* the disk copy procedure reuses the scrub code */
492 ret = btrfs_scrub_dev(fs_info, src_device->devid, 0,
493 btrfs_device_get_total_bytes(src_device),
494 &dev_replace->scrub_progress, 0, 1);
496 ret = btrfs_dev_replace_finishing(fs_info, ret);
497 if (ret == -EINPROGRESS) {
498 ret = BTRFS_IOCTL_DEV_REPLACE_RESULT_SCRUB_INPROGRESS;
506 dev_replace->srcdev = NULL;
507 dev_replace->tgtdev = NULL;
508 btrfs_dev_replace_write_unlock(dev_replace);
509 btrfs_destroy_dev_replace_tgtdev(tgt_device);
513 int btrfs_dev_replace_by_ioctl(struct btrfs_fs_info *fs_info,
514 struct btrfs_ioctl_dev_replace_args *args)
518 switch (args->start.cont_reading_from_srcdev_mode) {
519 case BTRFS_IOCTL_DEV_REPLACE_CONT_READING_FROM_SRCDEV_MODE_ALWAYS:
520 case BTRFS_IOCTL_DEV_REPLACE_CONT_READING_FROM_SRCDEV_MODE_AVOID:
526 if ((args->start.srcdevid == 0 && args->start.srcdev_name[0] == '\0') ||
527 args->start.tgtdev_name[0] == '\0')
530 ret = btrfs_dev_replace_start(fs_info, args->start.tgtdev_name,
531 args->start.srcdevid,
532 args->start.srcdev_name,
533 args->start.cont_reading_from_srcdev_mode);
535 /* don't warn if EINPROGRESS, someone else might be running scrub */
536 if (ret == BTRFS_IOCTL_DEV_REPLACE_RESULT_SCRUB_INPROGRESS)
543 * blocked until all in-flight bios operations are finished.
545 static void btrfs_rm_dev_replace_blocked(struct btrfs_fs_info *fs_info)
547 set_bit(BTRFS_FS_STATE_DEV_REPLACING, &fs_info->fs_state);
548 wait_event(fs_info->replace_wait, !percpu_counter_sum(
549 &fs_info->bio_counter));
553 * we have removed target device, it is safe to allow new bios request.
555 static void btrfs_rm_dev_replace_unblocked(struct btrfs_fs_info *fs_info)
557 clear_bit(BTRFS_FS_STATE_DEV_REPLACING, &fs_info->fs_state);
558 wake_up(&fs_info->replace_wait);
561 static int btrfs_dev_replace_finishing(struct btrfs_fs_info *fs_info,
564 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace;
565 struct btrfs_device *tgt_device;
566 struct btrfs_device *src_device;
567 struct btrfs_root *root = fs_info->tree_root;
568 u8 uuid_tmp[BTRFS_UUID_SIZE];
569 struct btrfs_trans_handle *trans;
572 /* don't allow cancel or unmount to disturb the finishing procedure */
573 mutex_lock(&dev_replace->lock_finishing_cancel_unmount);
575 btrfs_dev_replace_read_lock(dev_replace);
576 /* was the operation canceled, or is it finished? */
577 if (dev_replace->replace_state !=
578 BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED) {
579 btrfs_dev_replace_read_unlock(dev_replace);
580 mutex_unlock(&dev_replace->lock_finishing_cancel_unmount);
584 tgt_device = dev_replace->tgtdev;
585 src_device = dev_replace->srcdev;
586 btrfs_dev_replace_read_unlock(dev_replace);
589 * flush all outstanding I/O and inode extent mappings before the
590 * copy operation is declared as being finished
592 ret = btrfs_start_delalloc_roots(fs_info, -1);
594 mutex_unlock(&dev_replace->lock_finishing_cancel_unmount);
597 btrfs_wait_ordered_roots(fs_info, U64_MAX, 0, (u64)-1);
599 trans = btrfs_start_transaction(root, 0);
601 mutex_unlock(&dev_replace->lock_finishing_cancel_unmount);
602 return PTR_ERR(trans);
604 ret = btrfs_commit_transaction(trans);
607 /* keep away write_all_supers() during the finishing procedure */
608 mutex_lock(&fs_info->fs_devices->device_list_mutex);
609 mutex_lock(&fs_info->chunk_mutex);
610 btrfs_dev_replace_write_lock(dev_replace);
611 dev_replace->replace_state =
612 scrub_ret ? BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED
613 : BTRFS_IOCTL_DEV_REPLACE_STATE_FINISHED;
614 dev_replace->tgtdev = NULL;
615 dev_replace->srcdev = NULL;
616 dev_replace->time_stopped = ktime_get_real_seconds();
617 dev_replace->item_needs_writeback = 1;
619 /* replace old device with new one in mapping tree */
621 btrfs_dev_replace_update_device_in_mapping_tree(fs_info,
625 btrfs_err_in_rcu(fs_info,
626 "btrfs_scrub_dev(%s, %llu, %s) failed %d",
627 btrfs_dev_name(src_device),
629 rcu_str_deref(tgt_device->name), scrub_ret);
630 btrfs_dev_replace_write_unlock(dev_replace);
631 mutex_unlock(&fs_info->chunk_mutex);
632 mutex_unlock(&fs_info->fs_devices->device_list_mutex);
633 btrfs_rm_dev_replace_blocked(fs_info);
635 btrfs_destroy_dev_replace_tgtdev(tgt_device);
636 btrfs_rm_dev_replace_unblocked(fs_info);
637 mutex_unlock(&dev_replace->lock_finishing_cancel_unmount);
642 btrfs_info_in_rcu(fs_info,
643 "dev_replace from %s (devid %llu) to %s finished",
644 btrfs_dev_name(src_device),
646 rcu_str_deref(tgt_device->name));
647 clear_bit(BTRFS_DEV_STATE_REPLACE_TGT, &tgt_device->dev_state);
648 tgt_device->devid = src_device->devid;
649 src_device->devid = BTRFS_DEV_REPLACE_DEVID;
650 memcpy(uuid_tmp, tgt_device->uuid, sizeof(uuid_tmp));
651 memcpy(tgt_device->uuid, src_device->uuid, sizeof(tgt_device->uuid));
652 memcpy(src_device->uuid, uuid_tmp, sizeof(src_device->uuid));
653 btrfs_device_set_total_bytes(tgt_device, src_device->total_bytes);
654 btrfs_device_set_disk_total_bytes(tgt_device,
655 src_device->disk_total_bytes);
656 btrfs_device_set_bytes_used(tgt_device, src_device->bytes_used);
657 ASSERT(list_empty(&src_device->resized_list));
658 tgt_device->commit_total_bytes = src_device->commit_total_bytes;
659 tgt_device->commit_bytes_used = src_device->bytes_used;
661 btrfs_assign_next_active_device(src_device, tgt_device);
663 list_add(&tgt_device->dev_alloc_list, &fs_info->fs_devices->alloc_list);
664 fs_info->fs_devices->rw_devices++;
666 btrfs_dev_replace_write_unlock(dev_replace);
668 btrfs_rm_dev_replace_blocked(fs_info);
670 btrfs_rm_dev_replace_remove_srcdev(src_device);
672 btrfs_rm_dev_replace_unblocked(fs_info);
675 * Increment dev_stats_ccnt so that btrfs_run_dev_stats() will
676 * update on-disk dev stats value during commit transaction
678 atomic_inc(&tgt_device->dev_stats_ccnt);
681 * this is again a consistent state where no dev_replace procedure
682 * is running, the target device is part of the filesystem, the
683 * source device is not part of the filesystem anymore and its 1st
684 * superblock is scratched out so that it is no longer marked to
685 * belong to this filesystem.
687 mutex_unlock(&fs_info->chunk_mutex);
688 mutex_unlock(&fs_info->fs_devices->device_list_mutex);
690 /* replace the sysfs entry */
691 btrfs_sysfs_rm_device_link(fs_info->fs_devices, src_device);
692 btrfs_rm_dev_replace_free_srcdev(fs_info, src_device);
694 /* write back the superblocks */
695 trans = btrfs_start_transaction(root, 0);
697 btrfs_commit_transaction(trans);
699 mutex_unlock(&dev_replace->lock_finishing_cancel_unmount);
704 static void btrfs_dev_replace_update_device_in_mapping_tree(
705 struct btrfs_fs_info *fs_info,
706 struct btrfs_device *srcdev,
707 struct btrfs_device *tgtdev)
709 struct extent_map_tree *em_tree = &fs_info->mapping_tree.map_tree;
710 struct extent_map *em;
711 struct map_lookup *map;
715 write_lock(&em_tree->lock);
717 em = lookup_extent_mapping(em_tree, start, (u64)-1);
720 map = em->map_lookup;
721 for (i = 0; i < map->num_stripes; i++)
722 if (srcdev == map->stripes[i].dev)
723 map->stripes[i].dev = tgtdev;
724 start = em->start + em->len;
727 write_unlock(&em_tree->lock);
731 * Read progress of device replace status according to the state and last
732 * stored position. The value format is the same as for
733 * btrfs_dev_replace::progress_1000
735 static u64 btrfs_dev_replace_progress(struct btrfs_fs_info *fs_info)
737 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace;
740 switch (dev_replace->replace_state) {
741 case BTRFS_IOCTL_DEV_REPLACE_STATE_NEVER_STARTED:
742 case BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED:
745 case BTRFS_IOCTL_DEV_REPLACE_STATE_FINISHED:
748 case BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED:
749 case BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED:
750 ret = div64_u64(dev_replace->cursor_left,
751 div_u64(btrfs_device_get_total_bytes(
752 dev_replace->srcdev), 1000));
759 void btrfs_dev_replace_status(struct btrfs_fs_info *fs_info,
760 struct btrfs_ioctl_dev_replace_args *args)
762 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace;
764 btrfs_dev_replace_read_lock(dev_replace);
765 /* even if !dev_replace_is_valid, the values are good enough for
766 * the replace_status ioctl */
767 args->result = BTRFS_IOCTL_DEV_REPLACE_RESULT_NO_ERROR;
768 args->status.replace_state = dev_replace->replace_state;
769 args->status.time_started = dev_replace->time_started;
770 args->status.time_stopped = dev_replace->time_stopped;
771 args->status.num_write_errors =
772 atomic64_read(&dev_replace->num_write_errors);
773 args->status.num_uncorrectable_read_errors =
774 atomic64_read(&dev_replace->num_uncorrectable_read_errors);
775 args->status.progress_1000 = btrfs_dev_replace_progress(fs_info);
776 btrfs_dev_replace_read_unlock(dev_replace);
779 int btrfs_dev_replace_cancel(struct btrfs_fs_info *fs_info)
781 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace;
782 struct btrfs_device *tgt_device = NULL;
783 struct btrfs_device *src_device = NULL;
784 struct btrfs_trans_handle *trans;
785 struct btrfs_root *root = fs_info->tree_root;
789 if (sb_rdonly(fs_info->sb))
792 mutex_lock(&dev_replace->lock_finishing_cancel_unmount);
793 btrfs_dev_replace_write_lock(dev_replace);
794 switch (dev_replace->replace_state) {
795 case BTRFS_IOCTL_DEV_REPLACE_STATE_NEVER_STARTED:
796 case BTRFS_IOCTL_DEV_REPLACE_STATE_FINISHED:
797 case BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED:
798 result = BTRFS_IOCTL_DEV_REPLACE_RESULT_NOT_STARTED;
799 btrfs_dev_replace_write_unlock(dev_replace);
801 case BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED:
802 case BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED:
803 result = BTRFS_IOCTL_DEV_REPLACE_RESULT_NO_ERROR;
804 tgt_device = dev_replace->tgtdev;
805 src_device = dev_replace->srcdev;
806 dev_replace->tgtdev = NULL;
807 dev_replace->srcdev = NULL;
810 dev_replace->replace_state = BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED;
811 dev_replace->time_stopped = ktime_get_real_seconds();
812 dev_replace->item_needs_writeback = 1;
813 btrfs_dev_replace_write_unlock(dev_replace);
814 btrfs_scrub_cancel(fs_info);
816 trans = btrfs_start_transaction(root, 0);
818 mutex_unlock(&dev_replace->lock_finishing_cancel_unmount);
819 return PTR_ERR(trans);
821 ret = btrfs_commit_transaction(trans);
824 btrfs_info_in_rcu(fs_info,
825 "dev_replace from %s (devid %llu) to %s canceled",
826 btrfs_dev_name(src_device), src_device->devid,
827 btrfs_dev_name(tgt_device));
830 btrfs_destroy_dev_replace_tgtdev(tgt_device);
833 mutex_unlock(&dev_replace->lock_finishing_cancel_unmount);
837 void btrfs_dev_replace_suspend_for_unmount(struct btrfs_fs_info *fs_info)
839 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace;
841 mutex_lock(&dev_replace->lock_finishing_cancel_unmount);
842 btrfs_dev_replace_write_lock(dev_replace);
843 switch (dev_replace->replace_state) {
844 case BTRFS_IOCTL_DEV_REPLACE_STATE_NEVER_STARTED:
845 case BTRFS_IOCTL_DEV_REPLACE_STATE_FINISHED:
846 case BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED:
847 case BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED:
849 case BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED:
850 dev_replace->replace_state =
851 BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED;
852 dev_replace->time_stopped = ktime_get_real_seconds();
853 dev_replace->item_needs_writeback = 1;
854 btrfs_info(fs_info, "suspending dev_replace for unmount");
858 btrfs_dev_replace_write_unlock(dev_replace);
859 mutex_unlock(&dev_replace->lock_finishing_cancel_unmount);
862 /* resume dev_replace procedure that was interrupted by unmount */
863 int btrfs_resume_dev_replace_async(struct btrfs_fs_info *fs_info)
865 struct task_struct *task;
866 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace;
868 btrfs_dev_replace_write_lock(dev_replace);
869 switch (dev_replace->replace_state) {
870 case BTRFS_IOCTL_DEV_REPLACE_STATE_NEVER_STARTED:
871 case BTRFS_IOCTL_DEV_REPLACE_STATE_FINISHED:
872 case BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED:
873 btrfs_dev_replace_write_unlock(dev_replace);
875 case BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED:
877 case BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED:
878 dev_replace->replace_state =
879 BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED;
882 if (!dev_replace->tgtdev || !dev_replace->tgtdev->bdev) {
884 "cannot continue dev_replace, tgtdev is missing");
886 "you may cancel the operation after 'mount -o degraded'");
887 btrfs_dev_replace_write_unlock(dev_replace);
890 btrfs_dev_replace_write_unlock(dev_replace);
893 * This could collide with a paused balance, but the exclusive op logic
894 * should never allow both to start and pause. We don't want to allow
895 * dev-replace to start anyway.
897 if (test_and_set_bit(BTRFS_FS_EXCL_OP, &fs_info->flags)) {
899 "cannot resume dev-replace, other exclusive operation running");
903 task = kthread_run(btrfs_dev_replace_kthread, fs_info, "btrfs-devrepl");
904 return PTR_ERR_OR_ZERO(task);
907 static int btrfs_dev_replace_kthread(void *data)
909 struct btrfs_fs_info *fs_info = data;
910 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace;
914 progress = btrfs_dev_replace_progress(fs_info);
915 progress = div_u64(progress, 10);
916 btrfs_info_in_rcu(fs_info,
917 "continuing dev_replace from %s (devid %llu) to target %s @%u%%",
918 btrfs_dev_name(dev_replace->srcdev),
919 dev_replace->srcdev->devid,
920 btrfs_dev_name(dev_replace->tgtdev),
921 (unsigned int)progress);
923 ret = btrfs_scrub_dev(fs_info, dev_replace->srcdev->devid,
924 dev_replace->committed_cursor_left,
925 btrfs_device_get_total_bytes(dev_replace->srcdev),
926 &dev_replace->scrub_progress, 0, 1);
927 ret = btrfs_dev_replace_finishing(fs_info, ret);
930 clear_bit(BTRFS_FS_EXCL_OP, &fs_info->flags);
934 int btrfs_dev_replace_is_ongoing(struct btrfs_dev_replace *dev_replace)
936 if (!dev_replace->is_valid)
939 switch (dev_replace->replace_state) {
940 case BTRFS_IOCTL_DEV_REPLACE_STATE_NEVER_STARTED:
941 case BTRFS_IOCTL_DEV_REPLACE_STATE_FINISHED:
942 case BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED:
944 case BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED:
945 case BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED:
947 * return true even if tgtdev is missing (this is
948 * something that can happen if the dev_replace
949 * procedure is suspended by an umount and then
950 * the tgtdev is missing (or "btrfs dev scan") was
951 * not called and the the filesystem is remounted
952 * in degraded state. This does not stop the
953 * dev_replace procedure. It needs to be canceled
954 * manually if the cancellation is wanted.
961 void btrfs_dev_replace_read_lock(struct btrfs_dev_replace *dev_replace)
963 read_lock(&dev_replace->lock);
964 atomic_inc(&dev_replace->read_locks);
967 void btrfs_dev_replace_read_unlock(struct btrfs_dev_replace *dev_replace)
969 ASSERT(atomic_read(&dev_replace->read_locks) > 0);
970 atomic_dec(&dev_replace->read_locks);
971 read_unlock(&dev_replace->lock);
974 void btrfs_dev_replace_write_lock(struct btrfs_dev_replace *dev_replace)
977 wait_event(dev_replace->read_lock_wq,
978 atomic_read(&dev_replace->blocking_readers) == 0);
979 write_lock(&dev_replace->lock);
980 if (atomic_read(&dev_replace->blocking_readers)) {
981 write_unlock(&dev_replace->lock);
986 void btrfs_dev_replace_write_unlock(struct btrfs_dev_replace *dev_replace)
988 ASSERT(atomic_read(&dev_replace->blocking_readers) == 0);
989 write_unlock(&dev_replace->lock);
992 /* inc blocking cnt and release read lock */
993 void btrfs_dev_replace_set_lock_blocking(
994 struct btrfs_dev_replace *dev_replace)
996 /* only set blocking for read lock */
997 ASSERT(atomic_read(&dev_replace->read_locks) > 0);
998 atomic_inc(&dev_replace->blocking_readers);
999 read_unlock(&dev_replace->lock);
1002 /* acquire read lock and dec blocking cnt */
1003 void btrfs_dev_replace_clear_lock_blocking(
1004 struct btrfs_dev_replace *dev_replace)
1006 /* only set blocking for read lock */
1007 ASSERT(atomic_read(&dev_replace->read_locks) > 0);
1008 ASSERT(atomic_read(&dev_replace->blocking_readers) > 0);
1009 read_lock(&dev_replace->lock);
1010 /* Barrier implied by atomic_dec_and_test */
1011 if (atomic_dec_and_test(&dev_replace->blocking_readers))
1012 cond_wake_up_nomb(&dev_replace->read_lock_wq);
1015 void btrfs_bio_counter_inc_noblocked(struct btrfs_fs_info *fs_info)
1017 percpu_counter_inc(&fs_info->bio_counter);
1020 void btrfs_bio_counter_sub(struct btrfs_fs_info *fs_info, s64 amount)
1022 percpu_counter_sub(&fs_info->bio_counter, amount);
1023 cond_wake_up_nomb(&fs_info->replace_wait);
1026 void btrfs_bio_counter_inc_blocked(struct btrfs_fs_info *fs_info)
1029 percpu_counter_inc(&fs_info->bio_counter);
1030 if (likely(!test_bit(BTRFS_FS_STATE_DEV_REPLACING,
1031 &fs_info->fs_state)))
1034 btrfs_bio_counter_dec(fs_info);
1035 wait_event(fs_info->replace_wait,
1036 !test_bit(BTRFS_FS_STATE_DEV_REPLACING,
1037 &fs_info->fs_state));