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         return 0;
 148 }
 149 /**
 150  * get_log_header - read the log header for a given segment
 151  * @jd: the journal
 152  * @blk: the block to look at
 153  * @lh: the log header to return
 154  *
 155  * Read the log header for a given segement in a given journal.  Do a few
 156  * sanity checks on it.
 157  *
 158  * Returns: 0 on success,
 159  *          1 if the header was invalid or incomplete,
 160  *          errno on error
 161  */
 162
 163 static int get_log_header(struct gfs2_jdesc *jd, unsigned int blk,
 164                           struct gfs2_log_header_host *head)
 165 {
 166         struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
 167         struct buffer_head *bh;
 168         int error;
 169
 170         error = gfs2_replay_read_block(jd, blk, &bh);
 171         if (error)
 172                 return error;
 173
 174         error = __get_log_header(sdp, (const struct gfs2_log_header *)bh->b_data,
 175                                  blk, head);
 176         brelse(bh);
 177
 178         return error;
 179 }
 180
 181 /**
 182  * foreach_descriptor - go through the active part of the log
 183  * @jd: the journal
 184  * @start: the first log header in the active region
 185  * @end: the last log header (don't process the contents of this entry))
 186  *
 187  * Call a given function once for every log descriptor in the active
 188  * portion of the log.
 189  *
 190  * Returns: errno
 191  */
 192
 193 static int foreach_descriptor(struct gfs2_jdesc *jd, u32 start,
 194                               unsigned int end, int pass)
 195 {
 196         struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
 197         struct buffer_head *bh;
 198         struct gfs2_log_descriptor *ld;
 199         int error = 0;
 200         u32 length;
 201         __be64 *ptr;
 202         unsigned int offset = sizeof(struct gfs2_log_descriptor);
 203         offset += sizeof(__be64) - 1;
 204         offset &= ~(sizeof(__be64) - 1);
 205
 206         while (start != end) {
 207                 error = gfs2_replay_read_block(jd, start, &bh);
 208                 if (error)
 209                         return error;
 210                 if (gfs2_meta_check(sdp, bh)) {
 211                         brelse(bh);
 212                         return -EIO;
 213                 }
 214                 ld = (struct gfs2_log_descriptor *)bh->b_data;
 215                 length = be32_to_cpu(ld->ld_length);
 216
 217                 if (be32_to_cpu(ld->ld_header.mh_type) == GFS2_METATYPE_LH) {
 218                         struct gfs2_log_header_host lh;
 219                         error = get_log_header(jd, start, &lh);
 220                         if (!error) {
 221                                 gfs2_replay_incr_blk(jd, &start);
 222                                 brelse(bh);
 223                                 continue;
 224                         }
 225                         if (error == 1) {
 226                                 gfs2_consist_inode(GFS2_I(jd->jd_inode));
 227                                 error = -EIO;
 228                         }
 229                         brelse(bh);
 230                         return error;
 231                 } else if (gfs2_metatype_check(sdp, bh, GFS2_METATYPE_LD)) {
 232                         brelse(bh);
 233                         return -EIO;
 234                 }
 235                 ptr = (__be64 *)(bh->b_data + offset);
 236                 error = lops_scan_elements(jd, start, ld, ptr, pass);
 237                 if (error) {
 238                         brelse(bh);
 239                         return error;
 240                 }
 241
 242                 while (length--)
 243                         gfs2_replay_incr_blk(jd, &start);
 244
 245                 brelse(bh);
 246         }
 247
 248         return 0;
 249 }
 250
 251 /**
 252  * clean_journal - mark a dirty journal as being clean
 253  * @jd: the journal
 254  * @head: the head journal to start from
 255  *
 256  * Returns: errno
 257  */
 258
 259 static void clean_journal(struct gfs2_jdesc *jd,
 260                           struct gfs2_log_header_host *head)
 261 {
 262         struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
 263         u32 lblock = head->lh_blkno;
 264
 265         gfs2_replay_incr_blk(jd, &lblock);
 266         gfs2_write_log_header(sdp, jd, head->lh_sequence + 1, 0, lblock,
 267                               GFS2_LOG_HEAD_UNMOUNT | GFS2_LOG_HEAD_RECOVERY,
 268                               REQ_PREFLUSH | REQ_FUA | REQ_META | REQ_SYNC);
 269         if (jd->jd_jid == sdp->sd_lockstruct.ls_jid) {
 270                 sdp->sd_log_flush_head = lblock;
 271                 gfs2_log_incr_head(sdp);
 272         }
 273 }
 274
 275
 276 static void gfs2_recovery_done(struct gfs2_sbd *sdp, unsigned int jid,
 277                                unsigned int message)
 278 {
 279         char env_jid[20];
 280         char env_status[20];
 281         char *envp[] = { env_jid, env_status, NULL };
 282         struct lm_lockstruct *ls = &sdp->sd_lockstruct;
 283
 284         ls->ls_recover_jid_done = jid;
 285         ls->ls_recover_jid_status = message;
 286         sprintf(env_jid, "JID=%u", jid);
 287         sprintf(env_status, "RECOVERY=%s",
 288                 message == LM_RD_SUCCESS ? "Done" : "Failed");
 289         kobject_uevent_env(&sdp->sd_kobj, KOBJ_CHANGE, envp);
 290
 291         if (sdp->sd_lockstruct.ls_ops->lm_recovery_result)
 292                 sdp->sd_lockstruct.ls_ops->lm_recovery_result(sdp, jid, message);
 293 }
 294
 295 void gfs2_recover_func(struct work_struct *work)
 296 {
 297         struct gfs2_jdesc *jd = container_of(work, struct gfs2_jdesc, jd_work);
 298         struct gfs2_inode *ip = GFS2_I(jd->jd_inode);
 299         struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
 300         struct gfs2_log_header_host head;
 301         struct gfs2_holder j_gh, ji_gh, thaw_gh;
 302         ktime_t t_start, t_jlck, t_jhd, t_tlck, t_rep;
 303         int ro = 0;
 304         unsigned int pass;
 305         int error = 0;
 306         int jlocked = 0;
 307
 308         if (gfs2_withdrawn(sdp)) {
 309                 fs_err(sdp, "jid=%u: Recovery not attempted due to withdraw.\n",
 310                        jd->jd_jid);
 311                 goto fail;
 312         }
 313         t_start = ktime_get();
 314         if (sdp->sd_args.ar_spectator)
 315                 goto fail;
 316         if (jd->jd_jid != sdp->sd_lockstruct.ls_jid) {
 317                 fs_info(sdp, "jid=%u: Trying to acquire journal lock...\n",
 318                         jd->jd_jid);
 319                 jlocked = 1;
 320                 /* Acquire the journal lock so we can do recovery */
 321
 322                 error = gfs2_glock_nq_num(sdp, jd->jd_jid, &gfs2_journal_glops,
 323                                           LM_ST_EXCLUSIVE,
 324                                           LM_FLAG_NOEXP | LM_FLAG_TRY | GL_NOCACHE,
 325                                           &j_gh);
 326                 switch (error) {
 327                 case 0:
 328                         break;
 329
 330                 case GLR_TRYFAILED:
 331                         fs_info(sdp, "jid=%u: Busy\n", jd->jd_jid);
 332                         error = 0;
 333
 334                 default:
 335                         goto fail;
 336                 }
 337
 338                 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED,
 339                                            LM_FLAG_NOEXP | GL_NOCACHE, &ji_gh);
 340                 if (error)
 341                         goto fail_gunlock_j;
 342         } else {
 343                 fs_info(sdp, "jid=%u, already locked for use\n", jd->jd_jid);
 344         }
 345
 346         t_jlck = ktime_get();
 347         fs_info(sdp, "jid=%u: Looking at journal...\n", jd->jd_jid);
 348
 349         error = gfs2_jdesc_check(jd);
 350         if (error)
 351                 goto fail_gunlock_ji;
 352
 353         error = gfs2_find_jhead(jd, &head, true);
 354         if (error)
 355                 goto fail_gunlock_ji;
 356         t_jhd = ktime_get();
 357         fs_info(sdp, "jid=%u: Journal head lookup took %lldms\n", jd->jd_jid,
 358                 ktime_ms_delta(t_jhd, t_jlck));
 359
 360         if (!(head.lh_flags & GFS2_LOG_HEAD_UNMOUNT)) {
 361                 fs_info(sdp, "jid=%u: Acquiring the transaction lock...\n",
 362                         jd->jd_jid);
 363
 364                 /* Acquire a shared hold on the freeze lock */
 365
 366                 error = gfs2_glock_nq_init(sdp->sd_freeze_gl, LM_ST_SHARED,
 367                                            LM_FLAG_NOEXP | LM_FLAG_PRIORITY,
 368                                            &thaw_gh);
 369                 if (error)
 370                         goto fail_gunlock_ji;
 371
 372                 if (test_bit(SDF_RORECOVERY, &sdp->sd_flags)) {
 373                         ro = 1;
 374                 } else if (test_bit(SDF_JOURNAL_CHECKED, &sdp->sd_flags)) {
 375                         if (!test_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags))
 376                                 ro = 1;
 377                 } else {
 378                         if (sb_rdonly(sdp->sd_vfs)) {
 379                                 /* check if device itself is read-only */
 380                                 ro = bdev_read_only(sdp->sd_vfs->s_bdev);
 381                                 if (!ro) {
 382                                         fs_info(sdp, "recovery required on "
 383                                                 "read-only filesystem.\n");
 384                                         fs_info(sdp, "write access will be "
 385                                                 "enabled during recovery.\n");
 386                                 }
 387                         }
 388                 }
 389
 390                 if (ro) {
 391                         fs_warn(sdp, "jid=%u: Can't replay: read-only block "
 392                                 "device\n", jd->jd_jid);
 393                         error = -EROFS;
 394                         goto fail_gunlock_thaw;
 395                 }
 396
 397                 t_tlck = ktime_get();
 398                 fs_info(sdp, "jid=%u: Replaying journal...0x%x to 0x%x\n",
 399                         jd->jd_jid, head.lh_tail, head.lh_blkno);
 400
 401                 /* We take the sd_log_flush_lock here primarily to prevent log
 402                  * flushes and simultaneous journal replays from stomping on
 403                  * each other wrt sd_log_bio. */
 404                 down_read(&sdp->sd_log_flush_lock);
 405                 for (pass = 0; pass < 2; pass++) {
 406                         lops_before_scan(jd, &head, pass);
 407                         error = foreach_descriptor(jd, head.lh_tail,
 408                                                    head.lh_blkno, pass);
 409                         lops_after_scan(jd, error, pass);
 410                         if (error)
 411                                 goto fail_gunlock_thaw;
 412                 }
 413
 414                 clean_journal(jd, &head);
 415                 up_read(&sdp->sd_log_flush_lock);
 416
 417                 gfs2_glock_dq_uninit(&thaw_gh);
 418                 t_rep = ktime_get();
 419                 fs_info(sdp, "jid=%u: Journal replayed in %lldms [jlck:%lldms, "
 420                         "jhead:%lldms, tlck:%lldms, replay:%lldms]\n",
 421                         jd->jd_jid, ktime_ms_delta(t_rep, t_start),
 422                         ktime_ms_delta(t_jlck, t_start),
 423                         ktime_ms_delta(t_jhd, t_jlck),
 424                         ktime_ms_delta(t_tlck, t_jhd),
 425                         ktime_ms_delta(t_rep, t_tlck));
 426         }
 427
 428         gfs2_recovery_done(sdp, jd->jd_jid, LM_RD_SUCCESS);
 429
 430         if (jlocked) {
 431                 gfs2_glock_dq_uninit(&ji_gh);
 432                 gfs2_glock_dq_uninit(&j_gh);
 433         }
 434
 435         fs_info(sdp, "jid=%u: Done\n", jd->jd_jid);
 436         goto done;
 437
 438 fail_gunlock_thaw:
 439         gfs2_glock_dq_uninit(&thaw_gh);
 440 fail_gunlock_ji:
 441         if (jlocked) {
 442                 gfs2_glock_dq_uninit(&ji_gh);
 443 fail_gunlock_j:
 444                 gfs2_glock_dq_uninit(&j_gh);
 445         }
 446
 447         fs_info(sdp, "jid=%u: %s\n", jd->jd_jid, (error) ? "Failed" : "Done");
 448 fail:
 449         jd->jd_recover_error = error;
 450         gfs2_recovery_done(sdp, jd->jd_jid, LM_RD_GAVEUP);
 451 done:
 452         clear_bit(JDF_RECOVERY, &jd->jd_flags);
 453         smp_mb__after_atomic();
 454         wake_up_bit(&jd->jd_flags, JDF_RECOVERY);
 455 }
 456
 457 int gfs2_recover_journal(struct gfs2_jdesc *jd, bool wait)
 458 {
 459         int rv;
 460
 461         if (test_and_set_bit(JDF_RECOVERY, &jd->jd_flags))
 462                 return -EBUSY;
 463
 464         /* we have JDF_RECOVERY, queue should always succeed */
 465         rv = queue_work(gfs_recovery_wq, &jd->jd_work);
 466         BUG_ON(!rv);
 467
 468         if (wait)
 469                 wait_on_bit(&jd->jd_flags, JDF_RECOVERY,
 470                             TASK_UNINTERRUPTIBLE);
 471
 472         return wait ? jd->jd_recover_error : 0;
 473 }
 474