fs/gfs2/recovery.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 #include <linux/module.h>
   8 #include <linux/slab.h>
   9 #include <linux/spinlock.h>
  10 #include <linux/completion.h>
  11 #include <linux/buffer_head.h>
  12 #include <linux/gfs2_ondisk.h>
  13 #include <linux/crc32.h>
  14 #include <linux/crc32c.h>
  15 #include <linux/ktime.h>
  16
  17 #include "gfs2.h"
  18 #include "incore.h"
  19 #include "bmap.h"
  20 #include "glock.h"
  21 #include "glops.h"
  22 #include "log.h"
  23 #include "lops.h"
  24 #include "meta_io.h"
  25 #include "recovery.h"
  26 #include "super.h"
  27 #include "util.h"
  28 #include "dir.h"
  29
  30 struct workqueue_struct *gfs_recovery_wq;
  31
  32 int gfs2_replay_read_block(struct gfs2_jdesc *jd, unsigned int blk,
  33                            struct buffer_head **bh)
  34 {
  35         struct gfs2_inode *ip = GFS2_I(jd->jd_inode);
  36         struct gfs2_glock *gl = ip->i_gl;
  37         int new = 0;
  38         u64 dblock;
  39         u32 extlen;
  40         int error;
  41
  42         error = gfs2_extent_map(&ip->i_inode, blk, &new, &dblock, &extlen);
  43         if (error)
  44                 return error;
  45         if (!dblock) {
  46                 gfs2_consist_inode(ip);
  47                 return -EIO;
  48         }
  49
  50         *bh = gfs2_meta_ra(gl, dblock, extlen);
  51
  52         return error;
  53 }
  54
  55 int gfs2_revoke_add(struct gfs2_jdesc *jd, u64 blkno, unsigned int where)
  56 {
  57         struct list_head *head = &jd->jd_revoke_list;
  58         struct gfs2_revoke_replay *rr;
  59         int found = 0;
  60
  61         list_for_each_entry(rr, head, rr_list) {
  62                 if (rr->rr_blkno == blkno) {
  63                         found = 1;
  64                         break;
  65                 }
  66         }
  67
  68         if (found) {
  69                 rr->rr_where = where;
  70                 return 0;
  71         }
  72
  73         rr = kmalloc(sizeof(struct gfs2_revoke_replay), GFP_NOFS);
  74         if (!rr)
  75                 return -ENOMEM;
  76
  77         rr->rr_blkno = blkno;
  78         rr->rr_where = where;
  79         list_add(&rr->rr_list, head);
  80
  81         return 1;
  82 }
  83
  84 int gfs2_revoke_check(struct gfs2_jdesc *jd, u64 blkno, unsigned int where)
  85 {
  86         struct gfs2_revoke_replay *rr;
  87         int wrap, a, b, revoke;
  88         int found = 0;
  89
  90         list_for_each_entry(rr, &jd->jd_revoke_list, rr_list) {
  91                 if (rr->rr_blkno == blkno) {
  92                         found = 1;
  93                         break;
  94                 }
  95         }
  96
  97         if (!found)
  98                 return 0;
  99
 100         wrap = (rr->rr_where < jd->jd_replay_tail);
 101         a = (jd->jd_replay_tail < where);
 102         b = (where < rr->rr_where);
 103         revoke = (wrap) ? (a || b) : (a && b);
 104
 105         return revoke;
 106 }
 107
 108 void gfs2_revoke_clean(struct gfs2_jdesc *jd)
 109 {
 110         struct list_head *head = &jd->jd_revoke_list;
 111         struct gfs2_revoke_replay *rr;
 112
 113         while (!list_empty(head)) {
 114                 rr = list_first_entry(head, struct gfs2_revoke_replay, rr_list);
 115                 list_del(&rr->rr_list);
 116                 kfree(rr);
 117         }
 118 }
 119
 120 int __get_log_header(struct gfs2_sbd *sdp, const struct gfs2_log_header *lh,
 121                      unsigned int blkno, struct gfs2_log_header_host *head)
 122 {
 123         u32 hash, crc;
 124
 125         if (lh->lh_header.mh_magic != cpu_to_be32(GFS2_MAGIC) ||
 126             lh->lh_header.mh_type != cpu_to_be32(GFS2_METATYPE_LH) ||
 127             (blkno && be32_to_cpu(lh->lh_blkno) != blkno))
 128                 return 1;
 129
 130         hash = crc32(~0, lh, LH_V1_SIZE - 4);
 131         hash = ~crc32_le_shift(hash, 4); /* assume lh_hash is zero */
 132
 133         if (be32_to_cpu(lh->lh_hash) != hash)
 134                 return 1;
 135
 136         crc = crc32c(~0, (void *)lh + LH_V1_SIZE + 4,
 137                      sdp->sd_sb.sb_bsize - LH_V1_SIZE - 4);
 138
 139         if ((lh->lh_crc != 0 && be32_to_cpu(lh->lh_crc) != crc))
 140                 return 1;
 141
 142         head->lh_sequence = be64_to_cpu(lh->lh_sequence);
 143         head->lh_flags = be32_to_cpu(lh->lh_flags);
 144         head->lh_tail = be32_to_cpu(lh->lh_tail);
 145         head->lh_blkno = be32_to_cpu(lh->lh_blkno);
 146
 147         head->lh_local_total = be64_to_cpu(lh->lh_local_total);
 148         head->lh_local_free = be64_to_cpu(lh->lh_local_free);
 149         head->lh_local_dinodes = be64_to_cpu(lh->lh_local_dinodes);
 150
 151         return 0;
 152 }
 153 /**
 154  * get_log_header - read the log header for a given segment
 155  * @jd: the journal
 156  * @blk: the block to look at
 157  * @lh: the log header to return
 158  *
 159  * Read the log header for a given segement in a given journal.  Do a few
 160  * sanity checks on it.
 161  *
 162  * Returns: 0 on success,
 163  *          1 if the header was invalid or incomplete,
 164  *          errno on error
 165  */
 166
 167 static int get_log_header(struct gfs2_jdesc *jd, unsigned int blk,
 168                           struct gfs2_log_header_host *head)
 169 {
 170         struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
 171         struct buffer_head *bh;
 172         int error;
 173
 174         error = gfs2_replay_read_block(jd, blk, &bh);
 175         if (error)
 176                 return error;
 177
 178         error = __get_log_header(sdp, (const struct gfs2_log_header *)bh->b_data,
 179                                  blk, head);
 180         brelse(bh);
 181
 182         return error;
 183 }
 184
 185 /**
 186  * foreach_descriptor - go through the active part of the log
 187  * @jd: the journal
 188  * @start: the first log header in the active region
 189  * @end: the last log header (don't process the contents of this entry))
 190  *
 191  * Call a given function once for every log descriptor in the active
 192  * portion of the log.
 193  *
 194  * Returns: errno
 195  */
 196
 197 static int foreach_descriptor(struct gfs2_jdesc *jd, u32 start,
 198                               unsigned int end, int pass)
 199 {
 200         struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
 201         struct buffer_head *bh;
 202         struct gfs2_log_descriptor *ld;
 203         int error = 0;
 204         u32 length;
 205         __be64 *ptr;
 206         unsigned int offset = sizeof(struct gfs2_log_descriptor);
 207         offset += sizeof(__be64) - 1;
 208         offset &= ~(sizeof(__be64) - 1);
 209
 210         while (start != end) {
 211                 error = gfs2_replay_read_block(jd, start, &bh);
 212                 if (error)
 213                         return error;
 214                 if (gfs2_meta_check(sdp, bh)) {
 215                         brelse(bh);
 216                         return -EIO;
 217                 }
 218                 ld = (struct gfs2_log_descriptor *)bh->b_data;
 219                 length = be32_to_cpu(ld->ld_length);
 220
 221                 if (be32_to_cpu(ld->ld_header.mh_type) == GFS2_METATYPE_LH) {
 222                         struct gfs2_log_header_host lh;
 223                         error = get_log_header(jd, start, &lh);
 224                         if (!error) {
 225                                 gfs2_replay_incr_blk(jd, &start);
 226                                 brelse(bh);
 227                                 continue;
 228                         }
 229                         if (error == 1) {
 230                                 gfs2_consist_inode(GFS2_I(jd->jd_inode));
 231                                 error = -EIO;
 232                         }
 233                         brelse(bh);
 234                         return error;
 235                 } else if (gfs2_metatype_check(sdp, bh, GFS2_METATYPE_LD)) {
 236                         brelse(bh);
 237                         return -EIO;
 238                 }
 239                 ptr = (__be64 *)(bh->b_data + offset);
 240                 error = lops_scan_elements(jd, start, ld, ptr, pass);
 241                 if (error) {
 242                         brelse(bh);
 243                         return error;
 244                 }
 245
 246                 while (length--)
 247                         gfs2_replay_incr_blk(jd, &start);
 248
 249                 brelse(bh);
 250         }
 251
 252         return 0;
 253 }
 254
 255 /**
 256  * clean_journal - mark a dirty journal as being clean
 257  * @jd: the journal
 258  * @head: the head journal to start from
 259  *
 260  * Returns: errno
 261  */
 262
 263 static void clean_journal(struct gfs2_jdesc *jd,
 264                           struct gfs2_log_header_host *head)
 265 {
 266         struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
 267         u32 lblock = head->lh_blkno;
 268
 269         gfs2_replay_incr_blk(jd, &lblock);
 270         gfs2_write_log_header(sdp, jd, head->lh_sequence + 1, 0, lblock,
 271                               GFS2_LOG_HEAD_UNMOUNT | GFS2_LOG_HEAD_RECOVERY,
 272                               REQ_PREFLUSH | REQ_FUA | REQ_META | REQ_SYNC);
 273         if (jd->jd_jid == sdp->sd_lockstruct.ls_jid) {
 274                 sdp->sd_log_flush_head = lblock;
 275                 gfs2_log_incr_head(sdp);
 276         }
 277 }
 278
 279
 280 static void gfs2_recovery_done(struct gfs2_sbd *sdp, unsigned int jid,
 281                                unsigned int message)
 282 {
 283         char env_jid[20];
 284         char env_status[20];
 285         char *envp[] = { env_jid, env_status, NULL };
 286         struct lm_lockstruct *ls = &sdp->sd_lockstruct;
 287
 288         ls->ls_recover_jid_done = jid;
 289         ls->ls_recover_jid_status = message;
 290         sprintf(env_jid, "JID=%u", jid);
 291         sprintf(env_status, "RECOVERY=%s",
 292                 message == LM_RD_SUCCESS ? "Done" : "Failed");
 293         kobject_uevent_env(&sdp->sd_kobj, KOBJ_CHANGE, envp);
 294
 295         if (sdp->sd_lockstruct.ls_ops->lm_recovery_result)
 296                 sdp->sd_lockstruct.ls_ops->lm_recovery_result(sdp, jid, message);
 297 }
 298
 299 /**
 300  * update_statfs_inode - Update the master statfs inode or zero out the local
 301  *                       statfs inode for a given journal.
 302  * @jd: The journal
 303  * @head: If NULL, @inode is the local statfs inode and we need to zero it out.
 304  *        Otherwise, it @head contains the statfs change info that needs to be
 305  *        synced to the master statfs inode (pointed to by @inode).
 306  * @inode: statfs inode to update.
 307  */
 308 static int update_statfs_inode(struct gfs2_jdesc *jd,
 309                                struct gfs2_log_header_host *head,
 310                                struct inode *inode)
 311 {
 312         struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
 313         struct gfs2_inode *ip;
 314         struct buffer_head *bh;
 315         struct gfs2_statfs_change_host sc;
 316         int error = 0;
 317
 318         BUG_ON(!inode);
 319         ip = GFS2_I(inode);
 320
 321         error = gfs2_meta_inode_buffer(ip, &bh);
 322         if (error)
 323                 goto out;
 324
 325         spin_lock(&sdp->sd_statfs_spin);
 326
 327         if (head) { /* Update the master statfs inode */
 328                 gfs2_statfs_change_in(&sc, bh->b_data + sizeof(struct gfs2_dinode));
 329                 sc.sc_total += head->lh_local_total;
 330                 sc.sc_free += head->lh_local_free;
 331                 sc.sc_dinodes += head->lh_local_dinodes;
 332                 gfs2_statfs_change_out(&sc, bh->b_data + sizeof(struct gfs2_dinode));
 333
 334                 fs_info(sdp, "jid=%u: Updated master statfs Total:%lld, "
 335                         "Free:%lld, Dinodes:%lld after change "
 336                         "[%+lld,%+lld,%+lld]\n", jd->jd_jid, sc.sc_total,
 337                         sc.sc_free, sc.sc_dinodes, head->lh_local_total,
 338                         head->lh_local_free, head->lh_local_dinodes);
 339         } else { /* Zero out the local statfs inode */
 340                 memset(bh->b_data + sizeof(struct gfs2_dinode), 0,
 341                        sizeof(struct gfs2_statfs_change));
 342                 /* If it's our own journal, reset any in-memory changes too */
 343                 if (jd->jd_jid == sdp->sd_lockstruct.ls_jid) {
 344                         memset(&sdp->sd_statfs_local, 0,
 345                                sizeof(struct gfs2_statfs_change_host));
 346                 }
 347         }
 348         spin_unlock(&sdp->sd_statfs_spin);
 349
 350         mark_buffer_dirty(bh);
 351         brelse(bh);
 352         gfs2_inode_metasync(ip->i_gl);
 353
 354 out:
 355         return error;
 356 }
 357
 358 /**
 359  * recover_local_statfs - Update the master and local statfs changes for this
 360  *                        journal.
 361  *
 362  * Previously, statfs updates would be read in from the local statfs inode and
 363  * synced to the master statfs inode during recovery.
 364  *
 365  * We now use the statfs updates in the journal head to update the master statfs
 366  * inode instead of reading in from the local statfs inode. To preserve backward
 367  * compatibility with kernels that can't do this, we still need to keep the
 368  * local statfs inode up to date by writing changes to it. At some point in the
 369  * future, we can do away with the local statfs inodes altogether and keep the
 370  * statfs changes solely in the journal.
 371  *
 372  * @jd: the journal
 373  * @head: the journal head
 374  *
 375  * Returns: errno
 376  */
 377 static void recover_local_statfs(struct gfs2_jdesc *jd,
 378                                  struct gfs2_log_header_host *head)
 379 {
 380         int error;
 381         struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
 382
 383         if (!head->lh_local_total && !head->lh_local_free
 384             && !head->lh_local_dinodes) /* No change */
 385                 goto zero_local;
 386
 387          /* First update the master statfs inode with the changes we
 388           * found in the journal. */
 389         error = update_statfs_inode(jd, head, sdp->sd_statfs_inode);
 390         if (error)
 391                 goto out;
 392
 393 zero_local:
 394         /* Zero out the local statfs inode so any changes in there
 395          * are not re-recovered. */
 396         error = update_statfs_inode(jd, NULL,
 397                                     find_local_statfs_inode(sdp, jd->jd_jid));
 398 out:
 399         return;
 400 }
 401
 402 void gfs2_recover_func(struct work_struct *work)
 403 {
 404         struct gfs2_jdesc *jd = container_of(work, struct gfs2_jdesc, jd_work);
 405         struct gfs2_inode *ip = GFS2_I(jd->jd_inode);
 406         struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
 407         struct gfs2_log_header_host head;
 408         struct gfs2_holder j_gh, ji_gh, thaw_gh;
 409         ktime_t t_start, t_jlck, t_jhd, t_tlck, t_rep;
 410         int ro = 0;
 411         unsigned int pass;
 412         int error = 0;
 413         int jlocked = 0;
 414
 415         if (gfs2_withdrawn(sdp)) {
 416                 fs_err(sdp, "jid=%u: Recovery not attempted due to withdraw.\n",
 417                        jd->jd_jid);
 418                 goto fail;
 419         }
 420         t_start = ktime_get();
 421         if (sdp->sd_args.ar_spectator)
 422                 goto fail;
 423         if (jd->jd_jid != sdp->sd_lockstruct.ls_jid) {
 424                 fs_info(sdp, "jid=%u: Trying to acquire journal lock...\n",
 425                         jd->jd_jid);
 426                 jlocked = 1;
 427                 /* Acquire the journal lock so we can do recovery */
 428
 429                 error = gfs2_glock_nq_num(sdp, jd->jd_jid, &gfs2_journal_glops,
 430                                           LM_ST_EXCLUSIVE,
 431                                           LM_FLAG_NOEXP | LM_FLAG_TRY | GL_NOCACHE,
 432                                           &j_gh);
 433                 switch (error) {
 434                 case 0:
 435                         break;
 436
 437                 case GLR_TRYFAILED:
 438                         fs_info(sdp, "jid=%u: Busy\n", jd->jd_jid);
 439                         error = 0;
 440
 441                 default:
 442                         goto fail;
 443                 }
 444
 445                 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED,
 446                                            LM_FLAG_NOEXP | GL_NOCACHE, &ji_gh);
 447                 if (error)
 448                         goto fail_gunlock_j;
 449         } else {
 450                 fs_info(sdp, "jid=%u, already locked for use\n", jd->jd_jid);
 451         }
 452
 453         t_jlck = ktime_get();
 454         fs_info(sdp, "jid=%u: Looking at journal...\n", jd->jd_jid);
 455
 456         error = gfs2_jdesc_check(jd);
 457         if (error)
 458                 goto fail_gunlock_ji;
 459
 460         error = gfs2_find_jhead(jd, &head, true);
 461         if (error)
 462                 goto fail_gunlock_ji;
 463         t_jhd = ktime_get();
 464         fs_info(sdp, "jid=%u: Journal head lookup took %lldms\n", jd->jd_jid,
 465                 ktime_ms_delta(t_jhd, t_jlck));
 466
 467         if (!(head.lh_flags & GFS2_LOG_HEAD_UNMOUNT)) {
 468                 fs_info(sdp, "jid=%u: Acquiring the transaction lock...\n",
 469                         jd->jd_jid);
 470
 471                 /* Acquire a shared hold on the freeze lock */
 472
 473                 error = gfs2_glock_nq_init(sdp->sd_freeze_gl, LM_ST_SHARED,
 474                                            LM_FLAG_NOEXP | LM_FLAG_PRIORITY |
 475                                            GL_EXACT, &thaw_gh);
 476                 if (error)
 477                         goto fail_gunlock_ji;
 478
 479                 if (test_bit(SDF_RORECOVERY, &sdp->sd_flags)) {
 480                         ro = 1;
 481                 } else if (test_bit(SDF_JOURNAL_CHECKED, &sdp->sd_flags)) {
 482                         if (!test_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags))
 483                                 ro = 1;
 484                 } else {
 485                         if (sb_rdonly(sdp->sd_vfs)) {
 486                                 /* check if device itself is read-only */
 487                                 ro = bdev_read_only(sdp->sd_vfs->s_bdev);
 488                                 if (!ro) {
 489                                         fs_info(sdp, "recovery required on "
 490                                                 "read-only filesystem.\n");
 491                                         fs_info(sdp, "write access will be "
 492                                                 "enabled during recovery.\n");
 493                                 }
 494                         }
 495                 }
 496
 497                 if (ro) {
 498                         fs_warn(sdp, "jid=%u: Can't replay: read-only block "
 499                                 "device\n", jd->jd_jid);
 500                         error = -EROFS;
 501                         goto fail_gunlock_thaw;
 502                 }
 503
 504                 t_tlck = ktime_get();
 505                 fs_info(sdp, "jid=%u: Replaying journal...0x%x to 0x%x\n",
 506                         jd->jd_jid, head.lh_tail, head.lh_blkno);
 507
 508                 /* We take the sd_log_flush_lock here primarily to prevent log
 509                  * flushes and simultaneous journal replays from stomping on
 510                  * each other wrt sd_log_bio. */
 511                 down_read(&sdp->sd_log_flush_lock);
 512                 for (pass = 0; pass < 2; pass++) {
 513                         lops_before_scan(jd, &head, pass);
 514                         error = foreach_descriptor(jd, head.lh_tail,
 515                                                    head.lh_blkno, pass);
 516                         lops_after_scan(jd, error, pass);
 517                         if (error)
 518                                 goto fail_gunlock_thaw;
 519                 }
 520
 521                 recover_local_statfs(jd, &head);
 522                 clean_journal(jd, &head);
 523                 up_read(&sdp->sd_log_flush_lock);
 524
 525                 gfs2_glock_dq_uninit(&thaw_gh);
 526                 t_rep = ktime_get();
 527                 fs_info(sdp, "jid=%u: Journal replayed in %lldms [jlck:%lldms, "
 528                         "jhead:%lldms, tlck:%lldms, replay:%lldms]\n",
 529                         jd->jd_jid, ktime_ms_delta(t_rep, t_start),
 530                         ktime_ms_delta(t_jlck, t_start),
 531                         ktime_ms_delta(t_jhd, t_jlck),
 532                         ktime_ms_delta(t_tlck, t_jhd),
 533                         ktime_ms_delta(t_rep, t_tlck));
 534         }
 535
 536         gfs2_recovery_done(sdp, jd->jd_jid, LM_RD_SUCCESS);
 537
 538         if (jlocked) {
 539                 gfs2_glock_dq_uninit(&ji_gh);
 540                 gfs2_glock_dq_uninit(&j_gh);
 541         }
 542
 543         fs_info(sdp, "jid=%u: Done\n", jd->jd_jid);
 544         goto done;
 545
 546 fail_gunlock_thaw:
 547         gfs2_glock_dq_uninit(&thaw_gh);
 548 fail_gunlock_ji:
 549         if (jlocked) {
 550                 gfs2_glock_dq_uninit(&ji_gh);
 551 fail_gunlock_j:
 552                 gfs2_glock_dq_uninit(&j_gh);
 553         }
 554
 555         fs_info(sdp, "jid=%u: %s\n", jd->jd_jid, (error) ? "Failed" : "Done");
 556 fail:
 557         jd->jd_recover_error = error;
 558         gfs2_recovery_done(sdp, jd->jd_jid, LM_RD_GAVEUP);
 559 done:
 560         clear_bit(JDF_RECOVERY, &jd->jd_flags);
 561         smp_mb__after_atomic();
 562         wake_up_bit(&jd->jd_flags, JDF_RECOVERY);
 563 }
 564
 565 int gfs2_recover_journal(struct gfs2_jdesc *jd, bool wait)
 566 {
 567         int rv;
 568
 569         if (test_and_set_bit(JDF_RECOVERY, &jd->jd_flags))
 570                 return -EBUSY;
 571
 572         /* we have JDF_RECOVERY, queue should always succeed */
 573         rv = queue_work(gfs_recovery_wq, &jd->jd_work);
 574         BUG_ON(!rv);
 575
 576         if (wait)
 577                 wait_on_bit(&jd->jd_flags, JDF_RECOVERY,
 578                             TASK_UNINTERRUPTIBLE);
 579
 580         return wait ? jd->jd_recover_error : 0;
 581 }
 582