GNU Linux-libre 6.1.86-gnu
[releases.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                 /*
168                  * Dequeue any pending non-system glock holders that can no
169                  * longer be granted because the file system is withdrawn.
170                  */
171                 gfs2_gl_dq_holders(sdp);
172                 gfs2_freeze_unlock(&freeze_gh);
173         }
174
175         if (sdp->sd_lockstruct.ls_ops->lm_lock == NULL) { /* lock_nolock */
176                 if (!ret)
177                         ret = -EIO;
178                 clear_bit(SDF_WITHDRAW_RECOVERY, &sdp->sd_flags);
179                 goto skip_recovery;
180         }
181         /*
182          * Drop the glock for our journal so another node can recover it.
183          */
184         if (gfs2_holder_initialized(&sdp->sd_journal_gh)) {
185                 gfs2_glock_dq_wait(&sdp->sd_journal_gh);
186                 gfs2_holder_uninit(&sdp->sd_journal_gh);
187         }
188         sdp->sd_jinode_gh.gh_flags |= GL_NOCACHE;
189         gfs2_glock_dq(&sdp->sd_jinode_gh);
190         if (test_bit(SDF_FS_FROZEN, &sdp->sd_flags)) {
191                 /* Make sure gfs2_unfreeze works if partially-frozen */
192                 flush_work(&sdp->sd_freeze_work);
193                 atomic_set(&sdp->sd_freeze_state, SFS_FROZEN);
194                 thaw_super(sdp->sd_vfs);
195         } else {
196                 wait_on_bit(&i_gl->gl_flags, GLF_DEMOTE,
197                             TASK_UNINTERRUPTIBLE);
198         }
199
200         /*
201          * holder_uninit to force glock_put, to force dlm to let go
202          */
203         gfs2_holder_uninit(&sdp->sd_jinode_gh);
204
205         /*
206          * Note: We need to be careful here:
207          * Our iput of jd_inode will evict it. The evict will dequeue its
208          * glock, but the glock dq will wait for the withdraw unless we have
209          * exception code in glock_dq.
210          */
211         iput(inode);
212         sdp->sd_jdesc->jd_inode = NULL;
213         /*
214          * Wait until the journal inode's glock is freed. This allows try locks
215          * on other nodes to be successful, otherwise we remain the owner of
216          * the glock as far as dlm is concerned.
217          */
218         if (i_gl->gl_ops->go_free) {
219                 set_bit(GLF_FREEING, &i_gl->gl_flags);
220                 wait_on_bit(&i_gl->gl_flags, GLF_FREEING, TASK_UNINTERRUPTIBLE);
221         }
222
223         /*
224          * Dequeue the "live" glock, but keep a reference so it's never freed.
225          */
226         gfs2_glock_hold(live_gl);
227         gfs2_glock_dq_wait(&sdp->sd_live_gh);
228         /*
229          * We enqueue the "live" glock in EX so that all other nodes
230          * get a demote request and act on it. We don't really want the
231          * lock in EX, so we send a "try" lock with 1CB to produce a callback.
232          */
233         fs_warn(sdp, "Requesting recovery of jid %d.\n",
234                 sdp->sd_lockstruct.ls_jid);
235         gfs2_holder_reinit(LM_ST_EXCLUSIVE,
236                            LM_FLAG_TRY_1CB | LM_FLAG_NOEXP | GL_NOPID,
237                            &sdp->sd_live_gh);
238         msleep(GL_GLOCK_MAX_HOLD);
239         /*
240          * This will likely fail in a cluster, but succeed standalone:
241          */
242         ret = gfs2_glock_nq(&sdp->sd_live_gh);
243
244         /*
245          * If we actually got the "live" lock in EX mode, there are no other
246          * nodes available to replay our journal. So we try to replay it
247          * ourselves. We hold the "live" glock to prevent other mounters
248          * during recovery, then just dequeue it and reacquire it in our
249          * normal SH mode. Just in case the problem that caused us to
250          * withdraw prevents us from recovering our journal (e.g. io errors
251          * and such) we still check if the journal is clean before proceeding
252          * but we may wait forever until another mounter does the recovery.
253          */
254         if (ret == 0) {
255                 fs_warn(sdp, "No other mounters found. Trying to recover our "
256                         "own journal jid %d.\n", sdp->sd_lockstruct.ls_jid);
257                 if (gfs2_recover_journal(sdp->sd_jdesc, 1))
258                         fs_warn(sdp, "Unable to recover our journal jid %d.\n",
259                                 sdp->sd_lockstruct.ls_jid);
260                 gfs2_glock_dq_wait(&sdp->sd_live_gh);
261                 gfs2_holder_reinit(LM_ST_SHARED,
262                                    LM_FLAG_NOEXP | GL_EXACT | GL_NOPID,
263                                    &sdp->sd_live_gh);
264                 gfs2_glock_nq(&sdp->sd_live_gh);
265         }
266
267         gfs2_glock_queue_put(live_gl); /* drop extra reference we acquired */
268         clear_bit(SDF_WITHDRAW_RECOVERY, &sdp->sd_flags);
269
270         /*
271          * At this point our journal is evicted, so we need to get a new inode
272          * for it. Once done, we need to call gfs2_find_jhead which
273          * calls gfs2_map_journal_extents to map it for us again.
274          *
275          * Note that we don't really want it to look up a FREE block. The
276          * GFS2_BLKST_FREE simply overrides a block check in gfs2_inode_lookup
277          * which would otherwise fail because it requires grabbing an rgrp
278          * glock, which would fail with -EIO because we're withdrawing.
279          */
280         inode = gfs2_inode_lookup(sdp->sd_vfs, DT_UNKNOWN,
281                                   sdp->sd_jdesc->jd_no_addr, no_formal_ino,
282                                   GFS2_BLKST_FREE);
283         if (IS_ERR(inode)) {
284                 fs_warn(sdp, "Reprocessing of jid %d failed with %ld.\n",
285                         sdp->sd_lockstruct.ls_jid, PTR_ERR(inode));
286                 goto skip_recovery;
287         }
288         sdp->sd_jdesc->jd_inode = inode;
289         d_mark_dontcache(inode);
290
291         /*
292          * Now wait until recovery is complete.
293          */
294         for (tries = 0; tries < 10; tries++) {
295                 ret = check_journal_clean(sdp, sdp->sd_jdesc, false);
296                 if (!ret)
297                         break;
298                 msleep(HZ);
299                 fs_warn(sdp, "Waiting for journal recovery jid %d.\n",
300                         sdp->sd_lockstruct.ls_jid);
301         }
302 skip_recovery:
303         if (!ret)
304                 fs_warn(sdp, "Journal recovery complete for jid %d.\n",
305                         sdp->sd_lockstruct.ls_jid);
306         else
307                 fs_warn(sdp, "Journal recovery skipped for jid %d until next "
308                         "mount.\n", sdp->sd_lockstruct.ls_jid);
309         fs_warn(sdp, "Glock dequeues delayed: %lu\n", sdp->sd_glock_dqs_held);
310         sdp->sd_glock_dqs_held = 0;
311         wake_up_bit(&sdp->sd_flags, SDF_WITHDRAW_RECOVERY);
312 }
313
314 void gfs2_lm(struct gfs2_sbd *sdp, const char *fmt, ...)
315 {
316         struct va_format vaf;
317         va_list args;
318
319         if (sdp->sd_args.ar_errors == GFS2_ERRORS_WITHDRAW &&
320             test_bit(SDF_WITHDRAWN, &sdp->sd_flags))
321                 return;
322
323         va_start(args, fmt);
324         vaf.fmt = fmt;
325         vaf.va = &args;
326         fs_err(sdp, "%pV", &vaf);
327         va_end(args);
328 }
329
330 int gfs2_withdraw(struct gfs2_sbd *sdp)
331 {
332         struct lm_lockstruct *ls = &sdp->sd_lockstruct;
333         const struct lm_lockops *lm = ls->ls_ops;
334
335         if (sdp->sd_args.ar_errors == GFS2_ERRORS_WITHDRAW &&
336             test_and_set_bit(SDF_WITHDRAWN, &sdp->sd_flags)) {
337                 if (!test_bit(SDF_WITHDRAW_IN_PROG, &sdp->sd_flags))
338                         return -1;
339
340                 wait_on_bit(&sdp->sd_flags, SDF_WITHDRAW_IN_PROG,
341                             TASK_UNINTERRUPTIBLE);
342                 return -1;
343         }
344
345         set_bit(SDF_WITHDRAW_IN_PROG, &sdp->sd_flags);
346
347         if (sdp->sd_args.ar_errors == GFS2_ERRORS_WITHDRAW) {
348                 fs_err(sdp, "about to withdraw this file system\n");
349                 BUG_ON(sdp->sd_args.ar_debug);
350
351                 signal_our_withdraw(sdp);
352
353                 kobject_uevent(&sdp->sd_kobj, KOBJ_OFFLINE);
354
355                 if (!strcmp(sdp->sd_lockstruct.ls_ops->lm_proto_name, "lock_dlm"))
356                         wait_for_completion(&sdp->sd_wdack);
357
358                 if (lm->lm_unmount) {
359                         fs_err(sdp, "telling LM to unmount\n");
360                         lm->lm_unmount(sdp);
361                 }
362                 set_bit(SDF_SKIP_DLM_UNLOCK, &sdp->sd_flags);
363                 fs_err(sdp, "File system withdrawn\n");
364                 dump_stack();
365                 clear_bit(SDF_WITHDRAW_IN_PROG, &sdp->sd_flags);
366                 smp_mb__after_atomic();
367                 wake_up_bit(&sdp->sd_flags, SDF_WITHDRAW_IN_PROG);
368         }
369
370         if (sdp->sd_args.ar_errors == GFS2_ERRORS_PANIC)
371                 panic("GFS2: fsid=%s: panic requested\n", sdp->sd_fsname);
372
373         return -1;
374 }
375
376 /*
377  * gfs2_assert_withdraw_i - Cause the machine to withdraw if @assertion is false
378  */
379
380 void gfs2_assert_withdraw_i(struct gfs2_sbd *sdp, char *assertion,
381                             const char *function, char *file, unsigned int line,
382                             bool delayed)
383 {
384         if (gfs2_withdrawn(sdp))
385                 return;
386
387         fs_err(sdp,
388                "fatal: assertion \"%s\" failed\n"
389                "   function = %s, file = %s, line = %u\n",
390                assertion, function, file, line);
391
392         /*
393          * If errors=panic was specified on mount, it won't help to delay the
394          * withdraw.
395          */
396         if (sdp->sd_args.ar_errors == GFS2_ERRORS_PANIC)
397                 delayed = false;
398
399         if (delayed)
400                 gfs2_withdraw_delayed(sdp);
401         else
402                 gfs2_withdraw(sdp);
403         dump_stack();
404 }
405
406 /*
407  * gfs2_assert_warn_i - Print a message to the console if @assertion is false
408  */
409
410 void gfs2_assert_warn_i(struct gfs2_sbd *sdp, char *assertion,
411                         const char *function, char *file, unsigned int line)
412 {
413         if (time_before(jiffies,
414                         sdp->sd_last_warning +
415                         gfs2_tune_get(sdp, gt_complain_secs) * HZ))
416                 return;
417
418         if (sdp->sd_args.ar_errors == GFS2_ERRORS_WITHDRAW)
419                 fs_warn(sdp, "warning: assertion \"%s\" failed at function = %s, file = %s, line = %u\n",
420                         assertion, function, file, line);
421
422         if (sdp->sd_args.ar_debug)
423                 BUG();
424         else
425                 dump_stack();
426
427         if (sdp->sd_args.ar_errors == GFS2_ERRORS_PANIC)
428                 panic("GFS2: fsid=%s: warning: assertion \"%s\" failed\n"
429                       "GFS2: fsid=%s:   function = %s, file = %s, line = %u\n",
430                       sdp->sd_fsname, assertion,
431                       sdp->sd_fsname, function, file, line);
432
433         sdp->sd_last_warning = jiffies;
434 }
435
436 /*
437  * gfs2_consist_i - Flag a filesystem consistency error and withdraw
438  */
439
440 void gfs2_consist_i(struct gfs2_sbd *sdp, const char *function,
441                     char *file, unsigned int line)
442 {
443         gfs2_lm(sdp,
444                 "fatal: filesystem consistency error - function = %s, file = %s, line = %u\n",
445                 function, file, line);
446         gfs2_withdraw(sdp);
447 }
448
449 /*
450  * gfs2_consist_inode_i - Flag an inode consistency error and withdraw
451  */
452
453 void gfs2_consist_inode_i(struct gfs2_inode *ip,
454                           const char *function, char *file, unsigned int line)
455 {
456         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
457
458         gfs2_lm(sdp,
459                 "fatal: filesystem consistency error\n"
460                 "  inode = %llu %llu\n"
461                 "  function = %s, file = %s, line = %u\n",
462                 (unsigned long long)ip->i_no_formal_ino,
463                 (unsigned long long)ip->i_no_addr,
464                 function, file, line);
465         gfs2_dump_glock(NULL, ip->i_gl, 1);
466         gfs2_withdraw(sdp);
467 }
468
469 /*
470  * gfs2_consist_rgrpd_i - Flag a RG consistency error and withdraw
471  */
472
473 void gfs2_consist_rgrpd_i(struct gfs2_rgrpd *rgd,
474                           const char *function, char *file, unsigned int line)
475 {
476         struct gfs2_sbd *sdp = rgd->rd_sbd;
477         char fs_id_buf[sizeof(sdp->sd_fsname) + 7];
478
479         sprintf(fs_id_buf, "fsid=%s: ", sdp->sd_fsname);
480         gfs2_rgrp_dump(NULL, rgd, fs_id_buf);
481         gfs2_lm(sdp,
482                 "fatal: filesystem consistency error\n"
483                 "  RG = %llu\n"
484                 "  function = %s, file = %s, line = %u\n",
485                 (unsigned long long)rgd->rd_addr,
486                 function, file, line);
487         gfs2_dump_glock(NULL, rgd->rd_gl, 1);
488         gfs2_withdraw(sdp);
489 }
490
491 /*
492  * gfs2_meta_check_ii - Flag a magic number consistency error and withdraw
493  * Returns: -1 if this call withdrew the machine,
494  *          -2 if it was already withdrawn
495  */
496
497 int gfs2_meta_check_ii(struct gfs2_sbd *sdp, struct buffer_head *bh,
498                        const char *type, const char *function, char *file,
499                        unsigned int line)
500 {
501         int me;
502
503         gfs2_lm(sdp,
504                 "fatal: invalid metadata block\n"
505                 "  bh = %llu (%s)\n"
506                 "  function = %s, file = %s, line = %u\n",
507                 (unsigned long long)bh->b_blocknr, type,
508                 function, file, line);
509         me = gfs2_withdraw(sdp);
510         return (me) ? -1 : -2;
511 }
512
513 /*
514  * gfs2_metatype_check_ii - Flag a metadata type consistency error and withdraw
515  * Returns: -1 if this call withdrew the machine,
516  *          -2 if it was already withdrawn
517  */
518
519 int gfs2_metatype_check_ii(struct gfs2_sbd *sdp, struct buffer_head *bh,
520                            u16 type, u16 t, const char *function,
521                            char *file, unsigned int line)
522 {
523         int me;
524
525         gfs2_lm(sdp,
526                 "fatal: invalid metadata block\n"
527                 "  bh = %llu (type: exp=%u, found=%u)\n"
528                 "  function = %s, file = %s, line = %u\n",
529                 (unsigned long long)bh->b_blocknr, type, t,
530                 function, file, line);
531         me = gfs2_withdraw(sdp);
532         return (me) ? -1 : -2;
533 }
534
535 /*
536  * gfs2_io_error_i - Flag an I/O error and withdraw
537  * Returns: -1 if this call withdrew the machine,
538  *          0 if it was already withdrawn
539  */
540
541 int gfs2_io_error_i(struct gfs2_sbd *sdp, const char *function, char *file,
542                     unsigned int line)
543 {
544         gfs2_lm(sdp,
545                 "fatal: I/O error\n"
546                 "  function = %s, file = %s, line = %u\n",
547                 function, file, line);
548         return gfs2_withdraw(sdp);
549 }
550
551 /*
552  * gfs2_io_error_bh_i - Flag a buffer I/O error
553  * @withdraw: withdraw the filesystem
554  */
555
556 void gfs2_io_error_bh_i(struct gfs2_sbd *sdp, struct buffer_head *bh,
557                         const char *function, char *file, unsigned int line,
558                         bool withdraw)
559 {
560         if (gfs2_withdrawn(sdp))
561                 return;
562
563         fs_err(sdp, "fatal: I/O error\n"
564                "  block = %llu\n"
565                "  function = %s, file = %s, line = %u\n",
566                (unsigned long long)bh->b_blocknr, function, file, line);
567         if (withdraw)
568                 gfs2_withdraw(sdp);
569 }
570