GNU Linux-libre 5.10.219-gnu1
[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  *
48  * Returns: 0 if the journal is clean or locked, else an error
49  */
50 int check_journal_clean(struct gfs2_sbd *sdp, struct gfs2_jdesc *jd,
51                         bool verbose)
52 {
53         int error;
54         struct gfs2_holder j_gh;
55         struct gfs2_log_header_host head;
56         struct gfs2_inode *ip;
57
58         ip = GFS2_I(jd->jd_inode);
59         error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_NOEXP |
60                                    GL_EXACT | GL_NOCACHE, &j_gh);
61         if (error) {
62                 if (verbose)
63                         fs_err(sdp, "Error %d locking journal for spectator "
64                                "mount.\n", error);
65                 return -EPERM;
66         }
67         error = gfs2_jdesc_check(jd);
68         if (error) {
69                 if (verbose)
70                         fs_err(sdp, "Error checking journal for spectator "
71                                "mount.\n");
72                 goto out_unlock;
73         }
74         error = gfs2_find_jhead(jd, &head, false);
75         if (error) {
76                 if (verbose)
77                         fs_err(sdp, "Error parsing journal for spectator "
78                                "mount.\n");
79                 goto out_unlock;
80         }
81         if (!(head.lh_flags & GFS2_LOG_HEAD_UNMOUNT)) {
82                 error = -EPERM;
83                 if (verbose)
84                         fs_err(sdp, "jid=%u: Journal is dirty, so the first "
85                                "mounter must not be a spectator.\n",
86                                jd->jd_jid);
87         }
88
89 out_unlock:
90         gfs2_glock_dq_uninit(&j_gh);
91         return error;
92 }
93
94 /**
95  * gfs2_freeze_lock - hold the freeze glock
96  * @sdp: the superblock
97  * @freeze_gh: pointer to the requested holder
98  * @caller_flags: any additional flags needed by the caller
99  */
100 int gfs2_freeze_lock(struct gfs2_sbd *sdp, struct gfs2_holder *freeze_gh,
101                      int caller_flags)
102 {
103         int flags = LM_FLAG_NOEXP | GL_EXACT | caller_flags;
104         int error;
105
106         error = gfs2_glock_nq_init(sdp->sd_freeze_gl, LM_ST_SHARED, flags,
107                                    freeze_gh);
108         if (error && error != GLR_TRYFAILED)
109                 fs_err(sdp, "can't lock the freeze lock: %d\n", error);
110         return error;
111 }
112
113 void gfs2_freeze_unlock(struct gfs2_holder *freeze_gh)
114 {
115         if (gfs2_holder_initialized(freeze_gh))
116                 gfs2_glock_dq_uninit(freeze_gh);
117 }
118
119 static void signal_our_withdraw(struct gfs2_sbd *sdp)
120 {
121         struct gfs2_glock *live_gl = sdp->sd_live_gh.gh_gl;
122         struct inode *inode;
123         struct gfs2_inode *ip;
124         struct gfs2_glock *i_gl;
125         u64 no_formal_ino;
126         int log_write_allowed = test_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags);
127         int ret = 0;
128         int tries;
129
130         if (test_bit(SDF_NORECOVERY, &sdp->sd_flags) || !sdp->sd_jdesc)
131                 return;
132
133         inode = sdp->sd_jdesc->jd_inode;
134         ip = GFS2_I(inode);
135         i_gl = ip->i_gl;
136         no_formal_ino = ip->i_no_formal_ino;
137
138         /* Prevent any glock dq until withdraw recovery is complete */
139         set_bit(SDF_WITHDRAW_RECOVERY, &sdp->sd_flags);
140         /*
141          * Don't tell dlm we're bailing until we have no more buffers in the
142          * wind. If journal had an IO error, the log code should just purge
143          * the outstanding buffers rather than submitting new IO. Making the
144          * file system read-only will flush the journal, etc.
145          *
146          * During a normal unmount, gfs2_make_fs_ro calls gfs2_log_shutdown
147          * which clears SDF_JOURNAL_LIVE. In a withdraw, we must not write
148          * any UNMOUNT log header, so we can't call gfs2_log_shutdown, and
149          * therefore we need to clear SDF_JOURNAL_LIVE manually.
150          */
151         clear_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags);
152         if (!sb_rdonly(sdp->sd_vfs)) {
153                 struct gfs2_holder freeze_gh;
154
155                 gfs2_holder_mark_uninitialized(&freeze_gh);
156                 if (sdp->sd_freeze_gl &&
157                     !gfs2_glock_is_locked_by_me(sdp->sd_freeze_gl)) {
158                         ret = gfs2_freeze_lock(sdp, &freeze_gh,
159                                        log_write_allowed ? 0 : LM_FLAG_TRY);
160                         if (ret == GLR_TRYFAILED)
161                                 ret = 0;
162                 }
163                 if (!ret)
164                         ret = gfs2_make_fs_ro(sdp);
165                 gfs2_freeze_unlock(&freeze_gh);
166         }
167
168         if (sdp->sd_lockstruct.ls_ops->lm_lock == NULL) { /* lock_nolock */
169                 if (!ret)
170                         ret = -EIO;
171                 clear_bit(SDF_WITHDRAW_RECOVERY, &sdp->sd_flags);
172                 goto skip_recovery;
173         }
174         /*
175          * Drop the glock for our journal so another node can recover it.
176          */
177         if (gfs2_holder_initialized(&sdp->sd_journal_gh)) {
178                 gfs2_glock_dq_wait(&sdp->sd_journal_gh);
179                 gfs2_holder_uninit(&sdp->sd_journal_gh);
180         }
181         sdp->sd_jinode_gh.gh_flags |= GL_NOCACHE;
182         gfs2_glock_dq(&sdp->sd_jinode_gh);
183         if (test_bit(SDF_FS_FROZEN, &sdp->sd_flags)) {
184                 /* Make sure gfs2_unfreeze works if partially-frozen */
185                 flush_workqueue(gfs2_freeze_wq);
186                 atomic_set(&sdp->sd_freeze_state, SFS_FROZEN);
187                 thaw_super(sdp->sd_vfs);
188         } else {
189                 wait_on_bit(&i_gl->gl_flags, GLF_DEMOTE,
190                             TASK_UNINTERRUPTIBLE);
191         }
192
193         /*
194          * holder_uninit to force glock_put, to force dlm to let go
195          */
196         gfs2_holder_uninit(&sdp->sd_jinode_gh);
197
198         /*
199          * Note: We need to be careful here:
200          * Our iput of jd_inode will evict it. The evict will dequeue its
201          * glock, but the glock dq will wait for the withdraw unless we have
202          * exception code in glock_dq.
203          */
204         iput(inode);
205         /*
206          * Wait until the journal inode's glock is freed. This allows try locks
207          * on other nodes to be successful, otherwise we remain the owner of
208          * the glock as far as dlm is concerned.
209          */
210         if (i_gl->gl_ops->go_free) {
211                 set_bit(GLF_FREEING, &i_gl->gl_flags);
212                 wait_on_bit(&i_gl->gl_flags, GLF_FREEING, TASK_UNINTERRUPTIBLE);
213         }
214
215         /*
216          * Dequeue the "live" glock, but keep a reference so it's never freed.
217          */
218         gfs2_glock_hold(live_gl);
219         gfs2_glock_dq_wait(&sdp->sd_live_gh);
220         /*
221          * We enqueue the "live" glock in EX so that all other nodes
222          * get a demote request and act on it. We don't really want the
223          * lock in EX, so we send a "try" lock with 1CB to produce a callback.
224          */
225         fs_warn(sdp, "Requesting recovery of jid %d.\n",
226                 sdp->sd_lockstruct.ls_jid);
227         gfs2_holder_reinit(LM_ST_EXCLUSIVE, LM_FLAG_TRY_1CB | LM_FLAG_NOEXP,
228                            &sdp->sd_live_gh);
229         msleep(GL_GLOCK_MAX_HOLD);
230         /*
231          * This will likely fail in a cluster, but succeed standalone:
232          */
233         ret = gfs2_glock_nq(&sdp->sd_live_gh);
234
235         /*
236          * If we actually got the "live" lock in EX mode, there are no other
237          * nodes available to replay our journal. So we try to replay it
238          * ourselves. We hold the "live" glock to prevent other mounters
239          * during recovery, then just dequeue it and reacquire it in our
240          * normal SH mode. Just in case the problem that caused us to
241          * withdraw prevents us from recovering our journal (e.g. io errors
242          * and such) we still check if the journal is clean before proceeding
243          * but we may wait forever until another mounter does the recovery.
244          */
245         if (ret == 0) {
246                 fs_warn(sdp, "No other mounters found. Trying to recover our "
247                         "own journal jid %d.\n", sdp->sd_lockstruct.ls_jid);
248                 if (gfs2_recover_journal(sdp->sd_jdesc, 1))
249                         fs_warn(sdp, "Unable to recover our journal jid %d.\n",
250                                 sdp->sd_lockstruct.ls_jid);
251                 gfs2_glock_dq_wait(&sdp->sd_live_gh);
252                 gfs2_holder_reinit(LM_ST_SHARED, LM_FLAG_NOEXP | GL_EXACT,
253                                    &sdp->sd_live_gh);
254                 gfs2_glock_nq(&sdp->sd_live_gh);
255         }
256
257         gfs2_glock_queue_put(live_gl); /* drop extra reference we acquired */
258         clear_bit(SDF_WITHDRAW_RECOVERY, &sdp->sd_flags);
259
260         /*
261          * At this point our journal is evicted, so we need to get a new inode
262          * for it. Once done, we need to call gfs2_find_jhead which
263          * calls gfs2_map_journal_extents to map it for us again.
264          *
265          * Note that we don't really want it to look up a FREE block. The
266          * GFS2_BLKST_FREE simply overrides a block check in gfs2_inode_lookup
267          * which would otherwise fail because it requires grabbing an rgrp
268          * glock, which would fail with -EIO because we're withdrawing.
269          */
270         inode = gfs2_inode_lookup(sdp->sd_vfs, DT_UNKNOWN,
271                                   sdp->sd_jdesc->jd_no_addr, no_formal_ino,
272                                   GFS2_BLKST_FREE);
273         if (IS_ERR(inode)) {
274                 fs_warn(sdp, "Reprocessing of jid %d failed with %ld.\n",
275                         sdp->sd_lockstruct.ls_jid, PTR_ERR(inode));
276                 goto skip_recovery;
277         }
278         sdp->sd_jdesc->jd_inode = inode;
279
280         /*
281          * Now wait until recovery is complete.
282          */
283         for (tries = 0; tries < 10; tries++) {
284                 ret = check_journal_clean(sdp, sdp->sd_jdesc, false);
285                 if (!ret)
286                         break;
287                 msleep(HZ);
288                 fs_warn(sdp, "Waiting for journal recovery jid %d.\n",
289                         sdp->sd_lockstruct.ls_jid);
290         }
291 skip_recovery:
292         if (!ret)
293                 fs_warn(sdp, "Journal recovery complete for jid %d.\n",
294                         sdp->sd_lockstruct.ls_jid);
295         else
296                 fs_warn(sdp, "Journal recovery skipped for %d until next "
297                         "mount.\n", sdp->sd_lockstruct.ls_jid);
298         fs_warn(sdp, "Glock dequeues delayed: %lu\n", sdp->sd_glock_dqs_held);
299         sdp->sd_glock_dqs_held = 0;
300         wake_up_bit(&sdp->sd_flags, SDF_WITHDRAW_RECOVERY);
301 }
302
303 void gfs2_lm(struct gfs2_sbd *sdp, const char *fmt, ...)
304 {
305         struct va_format vaf;
306         va_list args;
307
308         if (sdp->sd_args.ar_errors == GFS2_ERRORS_WITHDRAW &&
309             test_bit(SDF_WITHDRAWN, &sdp->sd_flags))
310                 return;
311
312         va_start(args, fmt);
313         vaf.fmt = fmt;
314         vaf.va = &args;
315         fs_err(sdp, "%pV", &vaf);
316         va_end(args);
317 }
318
319 int gfs2_withdraw(struct gfs2_sbd *sdp)
320 {
321         struct lm_lockstruct *ls = &sdp->sd_lockstruct;
322         const struct lm_lockops *lm = ls->ls_ops;
323
324         if (sdp->sd_args.ar_errors == GFS2_ERRORS_WITHDRAW &&
325             test_and_set_bit(SDF_WITHDRAWN, &sdp->sd_flags)) {
326                 if (!test_bit(SDF_WITHDRAW_IN_PROG, &sdp->sd_flags))
327                         return -1;
328
329                 wait_on_bit(&sdp->sd_flags, SDF_WITHDRAW_IN_PROG,
330                             TASK_UNINTERRUPTIBLE);
331                 return -1;
332         }
333
334         set_bit(SDF_WITHDRAW_IN_PROG, &sdp->sd_flags);
335
336         if (sdp->sd_args.ar_errors == GFS2_ERRORS_WITHDRAW) {
337                 fs_err(sdp, "about to withdraw this file system\n");
338                 BUG_ON(sdp->sd_args.ar_debug);
339
340                 signal_our_withdraw(sdp);
341
342                 kobject_uevent(&sdp->sd_kobj, KOBJ_OFFLINE);
343
344                 if (!strcmp(sdp->sd_lockstruct.ls_ops->lm_proto_name, "lock_dlm"))
345                         wait_for_completion(&sdp->sd_wdack);
346
347                 if (lm->lm_unmount) {
348                         fs_err(sdp, "telling LM to unmount\n");
349                         lm->lm_unmount(sdp);
350                 }
351                 fs_err(sdp, "File system withdrawn\n");
352                 dump_stack();
353                 clear_bit(SDF_WITHDRAW_IN_PROG, &sdp->sd_flags);
354                 smp_mb__after_atomic();
355                 wake_up_bit(&sdp->sd_flags, SDF_WITHDRAW_IN_PROG);
356         }
357
358         if (sdp->sd_args.ar_errors == GFS2_ERRORS_PANIC)
359                 panic("GFS2: fsid=%s: panic requested\n", sdp->sd_fsname);
360
361         return -1;
362 }
363
364 /**
365  * gfs2_assert_withdraw_i - Cause the machine to withdraw if @assertion is false
366  */
367
368 void gfs2_assert_withdraw_i(struct gfs2_sbd *sdp, char *assertion,
369                             const char *function, char *file, unsigned int line,
370                             bool delayed)
371 {
372         if (gfs2_withdrawn(sdp))
373                 return;
374
375         fs_err(sdp,
376                "fatal: assertion \"%s\" failed\n"
377                "   function = %s, file = %s, line = %u\n",
378                assertion, function, file, line);
379
380         /*
381          * If errors=panic was specified on mount, it won't help to delay the
382          * withdraw.
383          */
384         if (sdp->sd_args.ar_errors == GFS2_ERRORS_PANIC)
385                 delayed = false;
386
387         if (delayed)
388                 gfs2_withdraw_delayed(sdp);
389         else
390                 gfs2_withdraw(sdp);
391         dump_stack();
392 }
393
394 /**
395  * gfs2_assert_warn_i - Print a message to the console if @assertion is false
396  */
397
398 void gfs2_assert_warn_i(struct gfs2_sbd *sdp, char *assertion,
399                         const char *function, char *file, unsigned int line)
400 {
401         if (time_before(jiffies,
402                         sdp->sd_last_warning +
403                         gfs2_tune_get(sdp, gt_complain_secs) * HZ))
404                 return;
405
406         if (sdp->sd_args.ar_errors == GFS2_ERRORS_WITHDRAW)
407                 fs_warn(sdp, "warning: assertion \"%s\" failed at function = %s, file = %s, line = %u\n",
408                         assertion, function, file, line);
409
410         if (sdp->sd_args.ar_debug)
411                 BUG();
412         else
413                 dump_stack();
414
415         if (sdp->sd_args.ar_errors == GFS2_ERRORS_PANIC)
416                 panic("GFS2: fsid=%s: warning: assertion \"%s\" failed\n"
417                       "GFS2: fsid=%s:   function = %s, file = %s, line = %u\n",
418                       sdp->sd_fsname, assertion,
419                       sdp->sd_fsname, function, file, line);
420
421         sdp->sd_last_warning = jiffies;
422 }
423
424 /**
425  * gfs2_consist_i - Flag a filesystem consistency error and withdraw
426  */
427
428 void gfs2_consist_i(struct gfs2_sbd *sdp, const char *function,
429                     char *file, unsigned int line)
430 {
431         gfs2_lm(sdp,
432                 "fatal: filesystem consistency error - function = %s, file = %s, line = %u\n",
433                 function, file, line);
434         gfs2_withdraw(sdp);
435 }
436
437 /**
438  * gfs2_consist_inode_i - Flag an inode consistency error and withdraw
439  */
440
441 void gfs2_consist_inode_i(struct gfs2_inode *ip,
442                           const char *function, char *file, unsigned int line)
443 {
444         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
445
446         gfs2_lm(sdp,
447                 "fatal: filesystem consistency error\n"
448                 "  inode = %llu %llu\n"
449                 "  function = %s, file = %s, line = %u\n",
450                 (unsigned long long)ip->i_no_formal_ino,
451                 (unsigned long long)ip->i_no_addr,
452                 function, file, line);
453         gfs2_withdraw(sdp);
454 }
455
456 /**
457  * gfs2_consist_rgrpd_i - Flag a RG consistency error and withdraw
458  */
459
460 void gfs2_consist_rgrpd_i(struct gfs2_rgrpd *rgd,
461                           const char *function, char *file, unsigned int line)
462 {
463         struct gfs2_sbd *sdp = rgd->rd_sbd;
464         char fs_id_buf[sizeof(sdp->sd_fsname) + 7];
465
466         sprintf(fs_id_buf, "fsid=%s: ", sdp->sd_fsname);
467         gfs2_rgrp_dump(NULL, rgd, fs_id_buf);
468         gfs2_lm(sdp,
469                 "fatal: filesystem consistency error\n"
470                 "  RG = %llu\n"
471                 "  function = %s, file = %s, line = %u\n",
472                 (unsigned long long)rgd->rd_addr,
473                 function, file, line);
474         gfs2_withdraw(sdp);
475 }
476
477 /**
478  * gfs2_meta_check_ii - Flag a magic number consistency error and withdraw
479  * Returns: -1 if this call withdrew the machine,
480  *          -2 if it was already withdrawn
481  */
482
483 int gfs2_meta_check_ii(struct gfs2_sbd *sdp, struct buffer_head *bh,
484                        const char *type, const char *function, char *file,
485                        unsigned int line)
486 {
487         int me;
488
489         gfs2_lm(sdp,
490                 "fatal: invalid metadata block\n"
491                 "  bh = %llu (%s)\n"
492                 "  function = %s, file = %s, line = %u\n",
493                 (unsigned long long)bh->b_blocknr, type,
494                 function, file, line);
495         me = gfs2_withdraw(sdp);
496         return (me) ? -1 : -2;
497 }
498
499 /**
500  * gfs2_metatype_check_ii - Flag a metadata type consistency error and withdraw
501  * Returns: -1 if this call withdrew the machine,
502  *          -2 if it was already withdrawn
503  */
504
505 int gfs2_metatype_check_ii(struct gfs2_sbd *sdp, struct buffer_head *bh,
506                            u16 type, u16 t, const char *function,
507                            char *file, unsigned int line)
508 {
509         int me;
510
511         gfs2_lm(sdp,
512                 "fatal: invalid metadata block\n"
513                 "  bh = %llu (type: exp=%u, found=%u)\n"
514                 "  function = %s, file = %s, line = %u\n",
515                 (unsigned long long)bh->b_blocknr, type, t,
516                 function, file, line);
517         me = gfs2_withdraw(sdp);
518         return (me) ? -1 : -2;
519 }
520
521 /**
522  * gfs2_io_error_i - Flag an I/O error and withdraw
523  * Returns: -1 if this call withdrew the machine,
524  *          0 if it was already withdrawn
525  */
526
527 int gfs2_io_error_i(struct gfs2_sbd *sdp, const char *function, char *file,
528                     unsigned int line)
529 {
530         gfs2_lm(sdp,
531                 "fatal: I/O error\n"
532                 "  function = %s, file = %s, line = %u\n",
533                 function, file, line);
534         return gfs2_withdraw(sdp);
535 }
536
537 /**
538  * gfs2_io_error_bh_i - Flag a buffer I/O error
539  * @withdraw: withdraw the filesystem
540  */
541
542 void gfs2_io_error_bh_i(struct gfs2_sbd *sdp, struct buffer_head *bh,
543                         const char *function, char *file, unsigned int line,
544                         bool withdraw)
545 {
546         if (gfs2_withdrawn(sdp))
547                 return;
548
549         fs_err(sdp, "fatal: I/O error\n"
550                "  block = %llu\n"
551                "  function = %s, file = %s, line = %u\n",
552                (unsigned long long)bh->b_blocknr, function, file, line);
553         if (withdraw)
554                 gfs2_withdraw(sdp);
555 }
556