Merge tag 'livepatching-for-5.15' of git://git.kernel.org/pub/scm/linux/kernel/git...
[platform/kernel/linux-rpi.git] / fs / gfs2 / util.c
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
4  * Copyright (C) 2004-2006 Red Hat, Inc.  All rights reserved.
5  */
6
7 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
8
9 #include <linux/spinlock.h>
10 #include <linux/completion.h>
11 #include <linux/buffer_head.h>
12 #include <linux/crc32.h>
13 #include <linux/gfs2_ondisk.h>
14 #include <linux/delay.h>
15 #include <linux/uaccess.h>
16
17 #include "gfs2.h"
18 #include "incore.h"
19 #include "glock.h"
20 #include "glops.h"
21 #include "log.h"
22 #include "lops.h"
23 #include "recovery.h"
24 #include "rgrp.h"
25 #include "super.h"
26 #include "util.h"
27
28 struct kmem_cache *gfs2_glock_cachep __read_mostly;
29 struct kmem_cache *gfs2_glock_aspace_cachep __read_mostly;
30 struct kmem_cache *gfs2_inode_cachep __read_mostly;
31 struct kmem_cache *gfs2_bufdata_cachep __read_mostly;
32 struct kmem_cache *gfs2_rgrpd_cachep __read_mostly;
33 struct kmem_cache *gfs2_quotad_cachep __read_mostly;
34 struct kmem_cache *gfs2_qadata_cachep __read_mostly;
35 struct kmem_cache *gfs2_trans_cachep __read_mostly;
36 mempool_t *gfs2_page_pool __read_mostly;
37
38 void gfs2_assert_i(struct gfs2_sbd *sdp)
39 {
40         fs_emerg(sdp, "fatal assertion failed\n");
41 }
42
43 /**
44  * check_journal_clean - Make sure a journal is clean for a spectator mount
45  * @sdp: The GFS2 superblock
46  * @jd: The journal descriptor
47  * @verbose: Show more prints in the log
48  *
49  * Returns: 0 if the journal is clean or locked, else an error
50  */
51 int check_journal_clean(struct gfs2_sbd *sdp, struct gfs2_jdesc *jd,
52                         bool verbose)
53 {
54         int error;
55         struct gfs2_holder j_gh;
56         struct gfs2_log_header_host head;
57         struct gfs2_inode *ip;
58
59         ip = GFS2_I(jd->jd_inode);
60         error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_NOEXP |
61                                    GL_EXACT | GL_NOCACHE, &j_gh);
62         if (error) {
63                 if (verbose)
64                         fs_err(sdp, "Error %d locking journal for spectator "
65                                "mount.\n", error);
66                 return -EPERM;
67         }
68         error = gfs2_jdesc_check(jd);
69         if (error) {
70                 if (verbose)
71                         fs_err(sdp, "Error checking journal for spectator "
72                                "mount.\n");
73                 goto out_unlock;
74         }
75         error = gfs2_find_jhead(jd, &head, false);
76         if (error) {
77                 if (verbose)
78                         fs_err(sdp, "Error parsing journal for spectator "
79                                "mount.\n");
80                 goto out_unlock;
81         }
82         if (!(head.lh_flags & GFS2_LOG_HEAD_UNMOUNT)) {
83                 error = -EPERM;
84                 if (verbose)
85                         fs_err(sdp, "jid=%u: Journal is dirty, so the first "
86                                "mounter must not be a spectator.\n",
87                                jd->jd_jid);
88         }
89
90 out_unlock:
91         gfs2_glock_dq_uninit(&j_gh);
92         return error;
93 }
94
95 /**
96  * gfs2_freeze_lock - hold the freeze glock
97  * @sdp: the superblock
98  * @freeze_gh: pointer to the requested holder
99  * @caller_flags: any additional flags needed by the caller
100  */
101 int gfs2_freeze_lock(struct gfs2_sbd *sdp, struct gfs2_holder *freeze_gh,
102                      int caller_flags)
103 {
104         int flags = LM_FLAG_NOEXP | GL_EXACT | caller_flags;
105         int error;
106
107         error = gfs2_glock_nq_init(sdp->sd_freeze_gl, LM_ST_SHARED, flags,
108                                    freeze_gh);
109         if (error && error != GLR_TRYFAILED)
110                 fs_err(sdp, "can't lock the freeze lock: %d\n", error);
111         return error;
112 }
113
114 void gfs2_freeze_unlock(struct gfs2_holder *freeze_gh)
115 {
116         if (gfs2_holder_initialized(freeze_gh))
117                 gfs2_glock_dq_uninit(freeze_gh);
118 }
119
120 static void signal_our_withdraw(struct gfs2_sbd *sdp)
121 {
122         struct gfs2_glock *live_gl = sdp->sd_live_gh.gh_gl;
123         struct inode *inode;
124         struct gfs2_inode *ip;
125         struct gfs2_glock *i_gl;
126         u64 no_formal_ino;
127         int log_write_allowed = test_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags);
128         int ret = 0;
129         int tries;
130
131         if (test_bit(SDF_NORECOVERY, &sdp->sd_flags) || !sdp->sd_jdesc)
132                 return;
133
134         gfs2_ail_drain(sdp); /* frees all transactions */
135         inode = sdp->sd_jdesc->jd_inode;
136         ip = GFS2_I(inode);
137         i_gl = ip->i_gl;
138         no_formal_ino = ip->i_no_formal_ino;
139
140         /* Prevent any glock dq until withdraw recovery is complete */
141         set_bit(SDF_WITHDRAW_RECOVERY, &sdp->sd_flags);
142         /*
143          * Don't tell dlm we're bailing until we have no more buffers in the
144          * wind. If journal had an IO error, the log code should just purge
145          * the outstanding buffers rather than submitting new IO. Making the
146          * file system read-only will flush the journal, etc.
147          *
148          * During a normal unmount, gfs2_make_fs_ro calls gfs2_log_shutdown
149          * which clears SDF_JOURNAL_LIVE. In a withdraw, we must not write
150          * any UNMOUNT log header, so we can't call gfs2_log_shutdown, and
151          * therefore we need to clear SDF_JOURNAL_LIVE manually.
152          */
153         clear_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags);
154         if (!sb_rdonly(sdp->sd_vfs)) {
155                 struct gfs2_holder freeze_gh;
156
157                 gfs2_holder_mark_uninitialized(&freeze_gh);
158                 if (sdp->sd_freeze_gl &&
159                     !gfs2_glock_is_locked_by_me(sdp->sd_freeze_gl)) {
160                         ret = gfs2_freeze_lock(sdp, &freeze_gh,
161                                        log_write_allowed ? 0 : LM_FLAG_TRY);
162                         if (ret == GLR_TRYFAILED)
163                                 ret = 0;
164                 }
165                 if (!ret)
166                         gfs2_make_fs_ro(sdp);
167                 gfs2_freeze_unlock(&freeze_gh);
168         }
169
170         if (sdp->sd_lockstruct.ls_ops->lm_lock == NULL) { /* lock_nolock */
171                 if (!ret)
172                         ret = -EIO;
173                 clear_bit(SDF_WITHDRAW_RECOVERY, &sdp->sd_flags);
174                 goto skip_recovery;
175         }
176         /*
177          * Drop the glock for our journal so another node can recover it.
178          */
179         if (gfs2_holder_initialized(&sdp->sd_journal_gh)) {
180                 gfs2_glock_dq_wait(&sdp->sd_journal_gh);
181                 gfs2_holder_uninit(&sdp->sd_journal_gh);
182         }
183         sdp->sd_jinode_gh.gh_flags |= GL_NOCACHE;
184         gfs2_glock_dq(&sdp->sd_jinode_gh);
185         if (test_bit(SDF_FS_FROZEN, &sdp->sd_flags)) {
186                 /* Make sure gfs2_unfreeze works if partially-frozen */
187                 flush_work(&sdp->sd_freeze_work);
188                 atomic_set(&sdp->sd_freeze_state, SFS_FROZEN);
189                 thaw_super(sdp->sd_vfs);
190         } else {
191                 wait_on_bit(&i_gl->gl_flags, GLF_DEMOTE,
192                             TASK_UNINTERRUPTIBLE);
193         }
194
195         /*
196          * holder_uninit to force glock_put, to force dlm to let go
197          */
198         gfs2_holder_uninit(&sdp->sd_jinode_gh);
199
200         /*
201          * Note: We need to be careful here:
202          * Our iput of jd_inode will evict it. The evict will dequeue its
203          * glock, but the glock dq will wait for the withdraw unless we have
204          * exception code in glock_dq.
205          */
206         iput(inode);
207         /*
208          * Wait until the journal inode's glock is freed. This allows try locks
209          * on other nodes to be successful, otherwise we remain the owner of
210          * the glock as far as dlm is concerned.
211          */
212         if (i_gl->gl_ops->go_free) {
213                 set_bit(GLF_FREEING, &i_gl->gl_flags);
214                 wait_on_bit(&i_gl->gl_flags, GLF_FREEING, TASK_UNINTERRUPTIBLE);
215         }
216
217         /*
218          * Dequeue the "live" glock, but keep a reference so it's never freed.
219          */
220         gfs2_glock_hold(live_gl);
221         gfs2_glock_dq_wait(&sdp->sd_live_gh);
222         /*
223          * We enqueue the "live" glock in EX so that all other nodes
224          * get a demote request and act on it. We don't really want the
225          * lock in EX, so we send a "try" lock with 1CB to produce a callback.
226          */
227         fs_warn(sdp, "Requesting recovery of jid %d.\n",
228                 sdp->sd_lockstruct.ls_jid);
229         gfs2_holder_reinit(LM_ST_EXCLUSIVE, LM_FLAG_TRY_1CB | LM_FLAG_NOEXP,
230                            &sdp->sd_live_gh);
231         msleep(GL_GLOCK_MAX_HOLD);
232         /*
233          * This will likely fail in a cluster, but succeed standalone:
234          */
235         ret = gfs2_glock_nq(&sdp->sd_live_gh);
236
237         /*
238          * If we actually got the "live" lock in EX mode, there are no other
239          * nodes available to replay our journal. So we try to replay it
240          * ourselves. We hold the "live" glock to prevent other mounters
241          * during recovery, then just dequeue it and reacquire it in our
242          * normal SH mode. Just in case the problem that caused us to
243          * withdraw prevents us from recovering our journal (e.g. io errors
244          * and such) we still check if the journal is clean before proceeding
245          * but we may wait forever until another mounter does the recovery.
246          */
247         if (ret == 0) {
248                 fs_warn(sdp, "No other mounters found. Trying to recover our "
249                         "own journal jid %d.\n", sdp->sd_lockstruct.ls_jid);
250                 if (gfs2_recover_journal(sdp->sd_jdesc, 1))
251                         fs_warn(sdp, "Unable to recover our journal jid %d.\n",
252                                 sdp->sd_lockstruct.ls_jid);
253                 gfs2_glock_dq_wait(&sdp->sd_live_gh);
254                 gfs2_holder_reinit(LM_ST_SHARED, LM_FLAG_NOEXP | GL_EXACT,
255                                    &sdp->sd_live_gh);
256                 gfs2_glock_nq(&sdp->sd_live_gh);
257         }
258
259         gfs2_glock_queue_put(live_gl); /* drop extra reference we acquired */
260         clear_bit(SDF_WITHDRAW_RECOVERY, &sdp->sd_flags);
261
262         /*
263          * At this point our journal is evicted, so we need to get a new inode
264          * for it. Once done, we need to call gfs2_find_jhead which
265          * calls gfs2_map_journal_extents to map it for us again.
266          *
267          * Note that we don't really want it to look up a FREE block. The
268          * GFS2_BLKST_FREE simply overrides a block check in gfs2_inode_lookup
269          * which would otherwise fail because it requires grabbing an rgrp
270          * glock, which would fail with -EIO because we're withdrawing.
271          */
272         inode = gfs2_inode_lookup(sdp->sd_vfs, DT_UNKNOWN,
273                                   sdp->sd_jdesc->jd_no_addr, no_formal_ino,
274                                   GFS2_BLKST_FREE);
275         if (IS_ERR(inode)) {
276                 fs_warn(sdp, "Reprocessing of jid %d failed with %ld.\n",
277                         sdp->sd_lockstruct.ls_jid, PTR_ERR(inode));
278                 goto skip_recovery;
279         }
280         sdp->sd_jdesc->jd_inode = inode;
281         d_mark_dontcache(inode);
282
283         /*
284          * Now wait until recovery is complete.
285          */
286         for (tries = 0; tries < 10; tries++) {
287                 ret = check_journal_clean(sdp, sdp->sd_jdesc, false);
288                 if (!ret)
289                         break;
290                 msleep(HZ);
291                 fs_warn(sdp, "Waiting for journal recovery jid %d.\n",
292                         sdp->sd_lockstruct.ls_jid);
293         }
294 skip_recovery:
295         if (!ret)
296                 fs_warn(sdp, "Journal recovery complete for jid %d.\n",
297                         sdp->sd_lockstruct.ls_jid);
298         else
299                 fs_warn(sdp, "Journal recovery skipped for jid %d until next "
300                         "mount.\n", sdp->sd_lockstruct.ls_jid);
301         fs_warn(sdp, "Glock dequeues delayed: %lu\n", sdp->sd_glock_dqs_held);
302         sdp->sd_glock_dqs_held = 0;
303         wake_up_bit(&sdp->sd_flags, SDF_WITHDRAW_RECOVERY);
304 }
305
306 void gfs2_lm(struct gfs2_sbd *sdp, const char *fmt, ...)
307 {
308         struct va_format vaf;
309         va_list args;
310
311         if (sdp->sd_args.ar_errors == GFS2_ERRORS_WITHDRAW &&
312             test_bit(SDF_WITHDRAWN, &sdp->sd_flags))
313                 return;
314
315         va_start(args, fmt);
316         vaf.fmt = fmt;
317         vaf.va = &args;
318         fs_err(sdp, "%pV", &vaf);
319         va_end(args);
320 }
321
322 int gfs2_withdraw(struct gfs2_sbd *sdp)
323 {
324         struct lm_lockstruct *ls = &sdp->sd_lockstruct;
325         const struct lm_lockops *lm = ls->ls_ops;
326
327         if (sdp->sd_args.ar_errors == GFS2_ERRORS_WITHDRAW &&
328             test_and_set_bit(SDF_WITHDRAWN, &sdp->sd_flags)) {
329                 if (!test_bit(SDF_WITHDRAW_IN_PROG, &sdp->sd_flags))
330                         return -1;
331
332                 wait_on_bit(&sdp->sd_flags, SDF_WITHDRAW_IN_PROG,
333                             TASK_UNINTERRUPTIBLE);
334                 return -1;
335         }
336
337         set_bit(SDF_WITHDRAW_IN_PROG, &sdp->sd_flags);
338
339         if (sdp->sd_args.ar_errors == GFS2_ERRORS_WITHDRAW) {
340                 fs_err(sdp, "about to withdraw this file system\n");
341                 BUG_ON(sdp->sd_args.ar_debug);
342
343                 signal_our_withdraw(sdp);
344
345                 kobject_uevent(&sdp->sd_kobj, KOBJ_OFFLINE);
346
347                 if (!strcmp(sdp->sd_lockstruct.ls_ops->lm_proto_name, "lock_dlm"))
348                         wait_for_completion(&sdp->sd_wdack);
349
350                 if (lm->lm_unmount) {
351                         fs_err(sdp, "telling LM to unmount\n");
352                         lm->lm_unmount(sdp);
353                 }
354                 set_bit(SDF_SKIP_DLM_UNLOCK, &sdp->sd_flags);
355                 fs_err(sdp, "File system withdrawn\n");
356                 dump_stack();
357                 clear_bit(SDF_WITHDRAW_IN_PROG, &sdp->sd_flags);
358                 smp_mb__after_atomic();
359                 wake_up_bit(&sdp->sd_flags, SDF_WITHDRAW_IN_PROG);
360         }
361
362         if (sdp->sd_args.ar_errors == GFS2_ERRORS_PANIC)
363                 panic("GFS2: fsid=%s: panic requested\n", sdp->sd_fsname);
364
365         return -1;
366 }
367
368 /*
369  * gfs2_assert_withdraw_i - Cause the machine to withdraw if @assertion is false
370  */
371
372 void gfs2_assert_withdraw_i(struct gfs2_sbd *sdp, char *assertion,
373                             const char *function, char *file, unsigned int line,
374                             bool delayed)
375 {
376         if (gfs2_withdrawn(sdp))
377                 return;
378
379         fs_err(sdp,
380                "fatal: assertion \"%s\" failed\n"
381                "   function = %s, file = %s, line = %u\n",
382                assertion, function, file, line);
383
384         /*
385          * If errors=panic was specified on mount, it won't help to delay the
386          * withdraw.
387          */
388         if (sdp->sd_args.ar_errors == GFS2_ERRORS_PANIC)
389                 delayed = false;
390
391         if (delayed)
392                 gfs2_withdraw_delayed(sdp);
393         else
394                 gfs2_withdraw(sdp);
395         dump_stack();
396 }
397
398 /*
399  * gfs2_assert_warn_i - Print a message to the console if @assertion is false
400  */
401
402 void gfs2_assert_warn_i(struct gfs2_sbd *sdp, char *assertion,
403                         const char *function, char *file, unsigned int line)
404 {
405         if (time_before(jiffies,
406                         sdp->sd_last_warning +
407                         gfs2_tune_get(sdp, gt_complain_secs) * HZ))
408                 return;
409
410         if (sdp->sd_args.ar_errors == GFS2_ERRORS_WITHDRAW)
411                 fs_warn(sdp, "warning: assertion \"%s\" failed at function = %s, file = %s, line = %u\n",
412                         assertion, function, file, line);
413
414         if (sdp->sd_args.ar_debug)
415                 BUG();
416         else
417                 dump_stack();
418
419         if (sdp->sd_args.ar_errors == GFS2_ERRORS_PANIC)
420                 panic("GFS2: fsid=%s: warning: assertion \"%s\" failed\n"
421                       "GFS2: fsid=%s:   function = %s, file = %s, line = %u\n",
422                       sdp->sd_fsname, assertion,
423                       sdp->sd_fsname, function, file, line);
424
425         sdp->sd_last_warning = jiffies;
426 }
427
428 /*
429  * gfs2_consist_i - Flag a filesystem consistency error and withdraw
430  */
431
432 void gfs2_consist_i(struct gfs2_sbd *sdp, const char *function,
433                     char *file, unsigned int line)
434 {
435         gfs2_lm(sdp,
436                 "fatal: filesystem consistency error - function = %s, file = %s, line = %u\n",
437                 function, file, line);
438         gfs2_withdraw(sdp);
439 }
440
441 /*
442  * gfs2_consist_inode_i - Flag an inode consistency error and withdraw
443  */
444
445 void gfs2_consist_inode_i(struct gfs2_inode *ip,
446                           const char *function, char *file, unsigned int line)
447 {
448         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
449
450         gfs2_lm(sdp,
451                 "fatal: filesystem consistency error\n"
452                 "  inode = %llu %llu\n"
453                 "  function = %s, file = %s, line = %u\n",
454                 (unsigned long long)ip->i_no_formal_ino,
455                 (unsigned long long)ip->i_no_addr,
456                 function, file, line);
457         gfs2_withdraw(sdp);
458 }
459
460 /*
461  * gfs2_consist_rgrpd_i - Flag a RG consistency error and withdraw
462  */
463
464 void gfs2_consist_rgrpd_i(struct gfs2_rgrpd *rgd,
465                           const char *function, char *file, unsigned int line)
466 {
467         struct gfs2_sbd *sdp = rgd->rd_sbd;
468         char fs_id_buf[sizeof(sdp->sd_fsname) + 7];
469
470         sprintf(fs_id_buf, "fsid=%s: ", sdp->sd_fsname);
471         gfs2_rgrp_dump(NULL, rgd, fs_id_buf);
472         gfs2_lm(sdp,
473                 "fatal: filesystem consistency error\n"
474                 "  RG = %llu\n"
475                 "  function = %s, file = %s, line = %u\n",
476                 (unsigned long long)rgd->rd_addr,
477                 function, file, line);
478         gfs2_withdraw(sdp);
479 }
480
481 /*
482  * gfs2_meta_check_ii - Flag a magic number consistency error and withdraw
483  * Returns: -1 if this call withdrew the machine,
484  *          -2 if it was already withdrawn
485  */
486
487 int gfs2_meta_check_ii(struct gfs2_sbd *sdp, struct buffer_head *bh,
488                        const char *type, const char *function, char *file,
489                        unsigned int line)
490 {
491         int me;
492
493         gfs2_lm(sdp,
494                 "fatal: invalid metadata block\n"
495                 "  bh = %llu (%s)\n"
496                 "  function = %s, file = %s, line = %u\n",
497                 (unsigned long long)bh->b_blocknr, type,
498                 function, file, line);
499         me = gfs2_withdraw(sdp);
500         return (me) ? -1 : -2;
501 }
502
503 /*
504  * gfs2_metatype_check_ii - Flag a metadata type consistency error and withdraw
505  * Returns: -1 if this call withdrew the machine,
506  *          -2 if it was already withdrawn
507  */
508
509 int gfs2_metatype_check_ii(struct gfs2_sbd *sdp, struct buffer_head *bh,
510                            u16 type, u16 t, const char *function,
511                            char *file, unsigned int line)
512 {
513         int me;
514
515         gfs2_lm(sdp,
516                 "fatal: invalid metadata block\n"
517                 "  bh = %llu (type: exp=%u, found=%u)\n"
518                 "  function = %s, file = %s, line = %u\n",
519                 (unsigned long long)bh->b_blocknr, type, t,
520                 function, file, line);
521         me = gfs2_withdraw(sdp);
522         return (me) ? -1 : -2;
523 }
524
525 /*
526  * gfs2_io_error_i - Flag an I/O error and withdraw
527  * Returns: -1 if this call withdrew the machine,
528  *          0 if it was already withdrawn
529  */
530
531 int gfs2_io_error_i(struct gfs2_sbd *sdp, const char *function, char *file,
532                     unsigned int line)
533 {
534         gfs2_lm(sdp,
535                 "fatal: I/O error\n"
536                 "  function = %s, file = %s, line = %u\n",
537                 function, file, line);
538         return gfs2_withdraw(sdp);
539 }
540
541 /*
542  * gfs2_io_error_bh_i - Flag a buffer I/O error
543  * @withdraw: withdraw the filesystem
544  */
545
546 void gfs2_io_error_bh_i(struct gfs2_sbd *sdp, struct buffer_head *bh,
547                         const char *function, char *file, unsigned int line,
548                         bool withdraw)
549 {
550         if (gfs2_withdrawn(sdp))
551                 return;
552
553         fs_err(sdp, "fatal: I/O error\n"
554                "  block = %llu\n"
555                "  function = %s, file = %s, line = %u\n",
556                (unsigned long long)bh->b_blocknr, function, file, line);
557         if (withdraw)
558                 gfs2_withdraw(sdp);
559 }
560