Merge tag 'arc-4.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc
[linux-2.6-microblaze.git] / fs / ocfs2 / filecheck.c
1 /* -*- mode: c; c-basic-offset: 8; -*-
2  * vim: noexpandtab sw=8 ts=8 sts=0:
3  *
4  * filecheck.c
5  *
6  * Code which implements online file check.
7  *
8  * Copyright (C) 2016 SuSE.  All rights reserved.
9  *
10  * This program is free software; you can redistribute it and/or
11  * modify it under the terms of the GNU General Public
12  * License as published by the Free Software Foundation, version 2.
13  *
14  * This program is distributed in the hope that it will be useful,
15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
17  * General Public License for more details.
18  */
19
20 #include <linux/list.h>
21 #include <linux/spinlock.h>
22 #include <linux/module.h>
23 #include <linux/slab.h>
24 #include <linux/kmod.h>
25 #include <linux/fs.h>
26 #include <linux/kobject.h>
27 #include <linux/sysfs.h>
28 #include <linux/sysctl.h>
29 #include <cluster/masklog.h>
30
31 #include "ocfs2.h"
32 #include "ocfs2_fs.h"
33 #include "stackglue.h"
34 #include "inode.h"
35
36 #include "filecheck.h"
37
38
39 /* File check error strings,
40  * must correspond with error number in header file.
41  */
42 static const char * const ocfs2_filecheck_errs[] = {
43         "SUCCESS",
44         "FAILED",
45         "INPROGRESS",
46         "READONLY",
47         "INJBD",
48         "INVALIDINO",
49         "BLOCKECC",
50         "BLOCKNO",
51         "VALIDFLAG",
52         "GENERATION",
53         "UNSUPPORTED"
54 };
55
56 static DEFINE_SPINLOCK(ocfs2_filecheck_sysfs_lock);
57 static LIST_HEAD(ocfs2_filecheck_sysfs_list);
58
59 struct ocfs2_filecheck {
60         struct list_head fc_head;       /* File check entry list head */
61         spinlock_t fc_lock;
62         unsigned int fc_max;    /* Maximum number of entry in list */
63         unsigned int fc_size;   /* Current entry count in list */
64         unsigned int fc_done;   /* Finished entry count in list */
65 };
66
67 struct ocfs2_filecheck_sysfs_entry {    /* sysfs entry per mounting */
68         struct list_head fs_list;
69         atomic_t fs_count;
70         struct super_block *fs_sb;
71         struct kset *fs_devicekset;
72         struct kset *fs_fcheckkset;
73         struct ocfs2_filecheck *fs_fcheck;
74 };
75
76 #define OCFS2_FILECHECK_MAXSIZE         100
77 #define OCFS2_FILECHECK_MINSIZE         10
78
79 /* File check operation type */
80 enum {
81         OCFS2_FILECHECK_TYPE_CHK = 0,   /* Check a file(inode) */
82         OCFS2_FILECHECK_TYPE_FIX,       /* Fix a file(inode) */
83         OCFS2_FILECHECK_TYPE_SET = 100  /* Set entry list maximum size */
84 };
85
86 struct ocfs2_filecheck_entry {
87         struct list_head fe_list;
88         unsigned long fe_ino;
89         unsigned int fe_type;
90         unsigned int fe_done:1;
91         unsigned int fe_status:31;
92 };
93
94 struct ocfs2_filecheck_args {
95         unsigned int fa_type;
96         union {
97                 unsigned long fa_ino;
98                 unsigned int fa_len;
99         };
100 };
101
102 static const char *
103 ocfs2_filecheck_error(int errno)
104 {
105         if (!errno)
106                 return ocfs2_filecheck_errs[errno];
107
108         BUG_ON(errno < OCFS2_FILECHECK_ERR_START ||
109                errno > OCFS2_FILECHECK_ERR_END);
110         return ocfs2_filecheck_errs[errno - OCFS2_FILECHECK_ERR_START + 1];
111 }
112
113 static ssize_t ocfs2_filecheck_show(struct kobject *kobj,
114                                     struct kobj_attribute *attr,
115                                     char *buf);
116 static ssize_t ocfs2_filecheck_store(struct kobject *kobj,
117                                      struct kobj_attribute *attr,
118                                      const char *buf, size_t count);
119 static struct kobj_attribute ocfs2_attr_filecheck_chk =
120                                         __ATTR(check, S_IRUSR | S_IWUSR,
121                                         ocfs2_filecheck_show,
122                                         ocfs2_filecheck_store);
123 static struct kobj_attribute ocfs2_attr_filecheck_fix =
124                                         __ATTR(fix, S_IRUSR | S_IWUSR,
125                                         ocfs2_filecheck_show,
126                                         ocfs2_filecheck_store);
127 static struct kobj_attribute ocfs2_attr_filecheck_set =
128                                         __ATTR(set, S_IRUSR | S_IWUSR,
129                                         ocfs2_filecheck_show,
130                                         ocfs2_filecheck_store);
131
132 static void
133 ocfs2_filecheck_sysfs_free(struct ocfs2_filecheck_sysfs_entry *entry)
134 {
135         struct ocfs2_filecheck_entry *p;
136
137         if (!atomic_dec_and_test(&entry->fs_count))
138                 wait_on_atomic_t(&entry->fs_count, atomic_t_wait,
139                                  TASK_UNINTERRUPTIBLE);
140
141         spin_lock(&entry->fs_fcheck->fc_lock);
142         while (!list_empty(&entry->fs_fcheck->fc_head)) {
143                 p = list_first_entry(&entry->fs_fcheck->fc_head,
144                                      struct ocfs2_filecheck_entry, fe_list);
145                 list_del(&p->fe_list);
146                 BUG_ON(!p->fe_done); /* To free a undone file check entry */
147                 kfree(p);
148         }
149         spin_unlock(&entry->fs_fcheck->fc_lock);
150
151         kset_unregister(entry->fs_fcheckkset);
152         kset_unregister(entry->fs_devicekset);
153         kfree(entry->fs_fcheck);
154         kfree(entry);
155 }
156
157 static void
158 ocfs2_filecheck_sysfs_add(struct ocfs2_filecheck_sysfs_entry *entry)
159 {
160         spin_lock(&ocfs2_filecheck_sysfs_lock);
161         list_add_tail(&entry->fs_list, &ocfs2_filecheck_sysfs_list);
162         spin_unlock(&ocfs2_filecheck_sysfs_lock);
163 }
164
165 static int ocfs2_filecheck_sysfs_del(const char *devname)
166 {
167         struct ocfs2_filecheck_sysfs_entry *p;
168
169         spin_lock(&ocfs2_filecheck_sysfs_lock);
170         list_for_each_entry(p, &ocfs2_filecheck_sysfs_list, fs_list) {
171                 if (!strcmp(p->fs_sb->s_id, devname)) {
172                         list_del(&p->fs_list);
173                         spin_unlock(&ocfs2_filecheck_sysfs_lock);
174                         ocfs2_filecheck_sysfs_free(p);
175                         return 0;
176                 }
177         }
178         spin_unlock(&ocfs2_filecheck_sysfs_lock);
179         return 1;
180 }
181
182 static void
183 ocfs2_filecheck_sysfs_put(struct ocfs2_filecheck_sysfs_entry *entry)
184 {
185         if (atomic_dec_and_test(&entry->fs_count))
186                 wake_up_atomic_t(&entry->fs_count);
187 }
188
189 static struct ocfs2_filecheck_sysfs_entry *
190 ocfs2_filecheck_sysfs_get(const char *devname)
191 {
192         struct ocfs2_filecheck_sysfs_entry *p = NULL;
193
194         spin_lock(&ocfs2_filecheck_sysfs_lock);
195         list_for_each_entry(p, &ocfs2_filecheck_sysfs_list, fs_list) {
196                 if (!strcmp(p->fs_sb->s_id, devname)) {
197                         atomic_inc(&p->fs_count);
198                         spin_unlock(&ocfs2_filecheck_sysfs_lock);
199                         return p;
200                 }
201         }
202         spin_unlock(&ocfs2_filecheck_sysfs_lock);
203         return NULL;
204 }
205
206 int ocfs2_filecheck_create_sysfs(struct super_block *sb)
207 {
208         int ret = 0;
209         struct kset *device_kset = NULL;
210         struct kset *fcheck_kset = NULL;
211         struct ocfs2_filecheck *fcheck = NULL;
212         struct ocfs2_filecheck_sysfs_entry *entry = NULL;
213         struct attribute **attrs = NULL;
214         struct attribute_group attrgp;
215
216         if (!ocfs2_kset)
217                 return -ENOMEM;
218
219         attrs = kmalloc(sizeof(struct attribute *) * 4, GFP_NOFS);
220         if (!attrs) {
221                 ret = -ENOMEM;
222                 goto error;
223         } else {
224                 attrs[0] = &ocfs2_attr_filecheck_chk.attr;
225                 attrs[1] = &ocfs2_attr_filecheck_fix.attr;
226                 attrs[2] = &ocfs2_attr_filecheck_set.attr;
227                 attrs[3] = NULL;
228                 memset(&attrgp, 0, sizeof(attrgp));
229                 attrgp.attrs = attrs;
230         }
231
232         fcheck = kmalloc(sizeof(struct ocfs2_filecheck), GFP_NOFS);
233         if (!fcheck) {
234                 ret = -ENOMEM;
235                 goto error;
236         } else {
237                 INIT_LIST_HEAD(&fcheck->fc_head);
238                 spin_lock_init(&fcheck->fc_lock);
239                 fcheck->fc_max = OCFS2_FILECHECK_MINSIZE;
240                 fcheck->fc_size = 0;
241                 fcheck->fc_done = 0;
242         }
243
244         if (strlen(sb->s_id) <= 0) {
245                 mlog(ML_ERROR,
246                 "Cannot get device basename when create filecheck sysfs\n");
247                 ret = -ENODEV;
248                 goto error;
249         }
250
251         device_kset = kset_create_and_add(sb->s_id, NULL, &ocfs2_kset->kobj);
252         if (!device_kset) {
253                 ret = -ENOMEM;
254                 goto error;
255         }
256
257         fcheck_kset = kset_create_and_add("filecheck", NULL,
258                                           &device_kset->kobj);
259         if (!fcheck_kset) {
260                 ret = -ENOMEM;
261                 goto error;
262         }
263
264         ret = sysfs_create_group(&fcheck_kset->kobj, &attrgp);
265         if (ret)
266                 goto error;
267
268         entry = kmalloc(sizeof(struct ocfs2_filecheck_sysfs_entry), GFP_NOFS);
269         if (!entry) {
270                 ret = -ENOMEM;
271                 goto error;
272         } else {
273                 atomic_set(&entry->fs_count, 1);
274                 entry->fs_sb = sb;
275                 entry->fs_devicekset = device_kset;
276                 entry->fs_fcheckkset = fcheck_kset;
277                 entry->fs_fcheck = fcheck;
278                 ocfs2_filecheck_sysfs_add(entry);
279         }
280
281         kfree(attrs);
282         return 0;
283
284 error:
285         kfree(attrs);
286         kfree(entry);
287         kfree(fcheck);
288         kset_unregister(fcheck_kset);
289         kset_unregister(device_kset);
290         return ret;
291 }
292
293 int ocfs2_filecheck_remove_sysfs(struct super_block *sb)
294 {
295         return ocfs2_filecheck_sysfs_del(sb->s_id);
296 }
297
298 static int
299 ocfs2_filecheck_erase_entries(struct ocfs2_filecheck_sysfs_entry *ent,
300                               unsigned int count);
301 static int
302 ocfs2_filecheck_adjust_max(struct ocfs2_filecheck_sysfs_entry *ent,
303                            unsigned int len)
304 {
305         int ret;
306
307         if ((len < OCFS2_FILECHECK_MINSIZE) || (len > OCFS2_FILECHECK_MAXSIZE))
308                 return -EINVAL;
309
310         spin_lock(&ent->fs_fcheck->fc_lock);
311         if (len < (ent->fs_fcheck->fc_size - ent->fs_fcheck->fc_done)) {
312                 mlog(ML_ERROR,
313                 "Cannot set online file check maximum entry number "
314                 "to %u due to too many pending entries(%u)\n",
315                 len, ent->fs_fcheck->fc_size - ent->fs_fcheck->fc_done);
316                 ret = -EBUSY;
317         } else {
318                 if (len < ent->fs_fcheck->fc_size)
319                         BUG_ON(!ocfs2_filecheck_erase_entries(ent,
320                                 ent->fs_fcheck->fc_size - len));
321
322                 ent->fs_fcheck->fc_max = len;
323                 ret = 0;
324         }
325         spin_unlock(&ent->fs_fcheck->fc_lock);
326
327         return ret;
328 }
329
330 #define OCFS2_FILECHECK_ARGS_LEN        24
331 static int
332 ocfs2_filecheck_args_get_long(const char *buf, size_t count,
333                               unsigned long *val)
334 {
335         char buffer[OCFS2_FILECHECK_ARGS_LEN];
336
337         memcpy(buffer, buf, count);
338         buffer[count] = '\0';
339
340         if (kstrtoul(buffer, 0, val))
341                 return 1;
342
343         return 0;
344 }
345
346 static int
347 ocfs2_filecheck_type_parse(const char *name, unsigned int *type)
348 {
349         if (!strncmp(name, "fix", 4))
350                 *type = OCFS2_FILECHECK_TYPE_FIX;
351         else if (!strncmp(name, "check", 6))
352                 *type = OCFS2_FILECHECK_TYPE_CHK;
353         else if (!strncmp(name, "set", 4))
354                 *type = OCFS2_FILECHECK_TYPE_SET;
355         else
356                 return 1;
357
358         return 0;
359 }
360
361 static int
362 ocfs2_filecheck_args_parse(const char *name, const char *buf, size_t count,
363                            struct ocfs2_filecheck_args *args)
364 {
365         unsigned long val = 0;
366         unsigned int type;
367
368         /* too short/long args length */
369         if ((count < 1) || (count >= OCFS2_FILECHECK_ARGS_LEN))
370                 return 1;
371
372         if (ocfs2_filecheck_type_parse(name, &type))
373                 return 1;
374         if (ocfs2_filecheck_args_get_long(buf, count, &val))
375                 return 1;
376
377         if (val <= 0)
378                 return 1;
379
380         args->fa_type = type;
381         if (type == OCFS2_FILECHECK_TYPE_SET)
382                 args->fa_len = (unsigned int)val;
383         else
384                 args->fa_ino = val;
385
386         return 0;
387 }
388
389 static ssize_t ocfs2_filecheck_show(struct kobject *kobj,
390                                     struct kobj_attribute *attr,
391                                     char *buf)
392 {
393
394         ssize_t ret = 0, total = 0, remain = PAGE_SIZE;
395         unsigned int type;
396         struct ocfs2_filecheck_entry *p;
397         struct ocfs2_filecheck_sysfs_entry *ent;
398
399         if (ocfs2_filecheck_type_parse(attr->attr.name, &type))
400                 return -EINVAL;
401
402         ent = ocfs2_filecheck_sysfs_get(kobj->parent->name);
403         if (!ent) {
404                 mlog(ML_ERROR,
405                 "Cannot get the corresponding entry via device basename %s\n",
406                 kobj->name);
407                 return -ENODEV;
408         }
409
410         if (type == OCFS2_FILECHECK_TYPE_SET) {
411                 spin_lock(&ent->fs_fcheck->fc_lock);
412                 total = snprintf(buf, remain, "%u\n", ent->fs_fcheck->fc_max);
413                 spin_unlock(&ent->fs_fcheck->fc_lock);
414                 goto exit;
415         }
416
417         ret = snprintf(buf, remain, "INO\t\tDONE\tERROR\n");
418         total += ret;
419         remain -= ret;
420         spin_lock(&ent->fs_fcheck->fc_lock);
421         list_for_each_entry(p, &ent->fs_fcheck->fc_head, fe_list) {
422                 if (p->fe_type != type)
423                         continue;
424
425                 ret = snprintf(buf + total, remain, "%lu\t\t%u\t%s\n",
426                                p->fe_ino, p->fe_done,
427                                ocfs2_filecheck_error(p->fe_status));
428                 if (ret < 0) {
429                         total = ret;
430                         break;
431                 }
432                 if (ret == remain) {
433                         /* snprintf() didn't fit */
434                         total = -E2BIG;
435                         break;
436                 }
437                 total += ret;
438                 remain -= ret;
439         }
440         spin_unlock(&ent->fs_fcheck->fc_lock);
441
442 exit:
443         ocfs2_filecheck_sysfs_put(ent);
444         return total;
445 }
446
447 static int
448 ocfs2_filecheck_erase_entry(struct ocfs2_filecheck_sysfs_entry *ent)
449 {
450         struct ocfs2_filecheck_entry *p;
451
452         list_for_each_entry(p, &ent->fs_fcheck->fc_head, fe_list) {
453                 if (p->fe_done) {
454                         list_del(&p->fe_list);
455                         kfree(p);
456                         ent->fs_fcheck->fc_size--;
457                         ent->fs_fcheck->fc_done--;
458                         return 1;
459                 }
460         }
461
462         return 0;
463 }
464
465 static int
466 ocfs2_filecheck_erase_entries(struct ocfs2_filecheck_sysfs_entry *ent,
467                               unsigned int count)
468 {
469         unsigned int i = 0;
470         unsigned int ret = 0;
471
472         while (i++ < count) {
473                 if (ocfs2_filecheck_erase_entry(ent))
474                         ret++;
475                 else
476                         break;
477         }
478
479         return (ret == count ? 1 : 0);
480 }
481
482 static void
483 ocfs2_filecheck_done_entry(struct ocfs2_filecheck_sysfs_entry *ent,
484                            struct ocfs2_filecheck_entry *entry)
485 {
486         entry->fe_done = 1;
487         spin_lock(&ent->fs_fcheck->fc_lock);
488         ent->fs_fcheck->fc_done++;
489         spin_unlock(&ent->fs_fcheck->fc_lock);
490 }
491
492 static unsigned int
493 ocfs2_filecheck_handle(struct super_block *sb,
494                        unsigned long ino, unsigned int flags)
495 {
496         unsigned int ret = OCFS2_FILECHECK_ERR_SUCCESS;
497         struct inode *inode = NULL;
498         int rc;
499
500         inode = ocfs2_iget(OCFS2_SB(sb), ino, flags, 0);
501         if (IS_ERR(inode)) {
502                 rc = (int)(-(long)inode);
503                 if (rc >= OCFS2_FILECHECK_ERR_START &&
504                     rc < OCFS2_FILECHECK_ERR_END)
505                         ret = rc;
506                 else
507                         ret = OCFS2_FILECHECK_ERR_FAILED;
508         } else
509                 iput(inode);
510
511         return ret;
512 }
513
514 static void
515 ocfs2_filecheck_handle_entry(struct ocfs2_filecheck_sysfs_entry *ent,
516                              struct ocfs2_filecheck_entry *entry)
517 {
518         if (entry->fe_type == OCFS2_FILECHECK_TYPE_CHK)
519                 entry->fe_status = ocfs2_filecheck_handle(ent->fs_sb,
520                                 entry->fe_ino, OCFS2_FI_FLAG_FILECHECK_CHK);
521         else if (entry->fe_type == OCFS2_FILECHECK_TYPE_FIX)
522                 entry->fe_status = ocfs2_filecheck_handle(ent->fs_sb,
523                                 entry->fe_ino, OCFS2_FI_FLAG_FILECHECK_FIX);
524         else
525                 entry->fe_status = OCFS2_FILECHECK_ERR_UNSUPPORTED;
526
527         ocfs2_filecheck_done_entry(ent, entry);
528 }
529
530 static ssize_t ocfs2_filecheck_store(struct kobject *kobj,
531                                      struct kobj_attribute *attr,
532                                      const char *buf, size_t count)
533 {
534         struct ocfs2_filecheck_args args;
535         struct ocfs2_filecheck_entry *entry;
536         struct ocfs2_filecheck_sysfs_entry *ent;
537         ssize_t ret = 0;
538
539         if (count == 0)
540                 return count;
541
542         if (ocfs2_filecheck_args_parse(attr->attr.name, buf, count, &args)) {
543                 mlog(ML_ERROR, "Invalid arguments for online file check\n");
544                 return -EINVAL;
545         }
546
547         ent = ocfs2_filecheck_sysfs_get(kobj->parent->name);
548         if (!ent) {
549                 mlog(ML_ERROR,
550                 "Cannot get the corresponding entry via device basename %s\n",
551                 kobj->parent->name);
552                 return -ENODEV;
553         }
554
555         if (args.fa_type == OCFS2_FILECHECK_TYPE_SET) {
556                 ret = ocfs2_filecheck_adjust_max(ent, args.fa_len);
557                 goto exit;
558         }
559
560         entry = kmalloc(sizeof(struct ocfs2_filecheck_entry), GFP_NOFS);
561         if (!entry) {
562                 ret = -ENOMEM;
563                 goto exit;
564         }
565
566         spin_lock(&ent->fs_fcheck->fc_lock);
567         if ((ent->fs_fcheck->fc_size >= ent->fs_fcheck->fc_max) &&
568             (ent->fs_fcheck->fc_done == 0)) {
569                 mlog(ML_ERROR,
570                 "Cannot do more file check "
571                 "since file check queue(%u) is full now\n",
572                 ent->fs_fcheck->fc_max);
573                 ret = -EBUSY;
574                 kfree(entry);
575         } else {
576                 if ((ent->fs_fcheck->fc_size >= ent->fs_fcheck->fc_max) &&
577                     (ent->fs_fcheck->fc_done > 0)) {
578                         /* Delete the oldest entry which was done,
579                          * make sure the entry size in list does
580                          * not exceed maximum value
581                          */
582                         BUG_ON(!ocfs2_filecheck_erase_entry(ent));
583                 }
584
585                 entry->fe_ino = args.fa_ino;
586                 entry->fe_type = args.fa_type;
587                 entry->fe_done = 0;
588                 entry->fe_status = OCFS2_FILECHECK_ERR_INPROGRESS;
589                 list_add_tail(&entry->fe_list, &ent->fs_fcheck->fc_head);
590                 ent->fs_fcheck->fc_size++;
591         }
592         spin_unlock(&ent->fs_fcheck->fc_lock);
593
594         if (!ret)
595                 ocfs2_filecheck_handle_entry(ent, entry);
596
597 exit:
598         ocfs2_filecheck_sysfs_put(ent);
599         return (!ret ? count : ret);
600 }