fs/gfs2/recovery.c

   1 /*
   2  * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
   3  * Copyright (C) 2004-2006 Red Hat, Inc.  All rights reserved.
   4  *
   5  * This copyrighted material is made available to anyone wishing to use,
   6  * modify, copy, or redistribute it subject to the terms and conditions
   7  * of the GNU General Public License version 2.
   8  */
   9
  10 #include <linux/module.h>
  11 #include <linux/slab.h>
  12 #include <linux/spinlock.h>
  13 #include <linux/completion.h>
  14 #include <linux/buffer_head.h>
  15 #include <linux/gfs2_ondisk.h>
  16 #include <linux/crc32.h>
  17 #include <linux/crc32c.h>
  18 #include <linux/ktime.h>
  19
  20 #include "gfs2.h"
  21 #include "incore.h"
  22 #include "bmap.h"
  23 #include "glock.h"
  24 #include "glops.h"
  25 #include "log.h"
  26 #include "lops.h"
  27 #include "meta_io.h"
  28 #include "recovery.h"
  29 #include "super.h"
  30 #include "util.h"
  31 #include "dir.h"
  32
  33 struct workqueue_struct *gfs_recovery_wq;
  34
  35 int gfs2_replay_read_block(struct gfs2_jdesc *jd, unsigned int blk,
  36                            struct buffer_head **bh)
  37 {
  38         struct gfs2_inode *ip = GFS2_I(jd->jd_inode);
  39         struct gfs2_glock *gl = ip->i_gl;
  40         int new = 0;
  41         u64 dblock;
  42         u32 extlen;
  43         int error;
  44
  45         error = gfs2_extent_map(&ip->i_inode, blk, &new, &dblock, &extlen);
  46         if (error)
  47                 return error;
  48         if (!dblock) {
  49                 gfs2_consist_inode(ip);
  50                 return -EIO;
  51         }
  52
  53         *bh = gfs2_meta_ra(gl, dblock, extlen);
  54
  55         return error;
  56 }
  57
  58 int gfs2_revoke_add(struct gfs2_jdesc *jd, u64 blkno, unsigned int where)
  59 {
  60         struct list_head *head = &jd->jd_revoke_list;
  61         struct gfs2_revoke_replay *rr;
  62         int found = 0;
  63
  64         list_for_each_entry(rr, head, rr_list) {
  65                 if (rr->rr_blkno == blkno) {
  66                         found = 1;
  67                         break;
  68                 }
  69         }
  70
  71         if (found) {
  72                 rr->rr_where = where;
  73                 return 0;
  74         }
  75
  76         rr = kmalloc(sizeof(struct gfs2_revoke_replay), GFP_NOFS);
  77         if (!rr)
  78                 return -ENOMEM;
  79
  80         rr->rr_blkno = blkno;
  81         rr->rr_where = where;
  82         list_add(&rr->rr_list, head);
  83
  84         return 1;
  85 }
  86
  87 int gfs2_revoke_check(struct gfs2_jdesc *jd, u64 blkno, unsigned int where)
  88 {
  89         struct gfs2_revoke_replay *rr;
  90         int wrap, a, b, revoke;
  91         int found = 0;
  92
  93         list_for_each_entry(rr, &jd->jd_revoke_list, rr_list) {
  94                 if (rr->rr_blkno == blkno) {
  95                         found = 1;
  96                         break;
  97                 }
  98         }
  99
 100         if (!found)
 101                 return 0;
 102
 103         wrap = (rr->rr_where < jd->jd_replay_tail);
 104         a = (jd->jd_replay_tail < where);
 105         b = (where < rr->rr_where);
 106         revoke = (wrap) ? (a || b) : (a && b);
 107
 108         return revoke;
 109 }
 110
 111 void gfs2_revoke_clean(struct gfs2_jdesc *jd)
 112 {
 113         struct list_head *head = &jd->jd_revoke_list;
 114         struct gfs2_revoke_replay *rr;
 115
 116         while (!list_empty(head)) {
 117                 rr = list_entry(head->next, struct gfs2_revoke_replay, rr_list);
 118                 list_del(&rr->rr_list);
 119                 kfree(rr);
 120         }
 121 }
 122
 123 int __get_log_header(struct gfs2_sbd *sdp, const struct gfs2_log_header *lh,
 124                      unsigned int blkno, struct gfs2_log_header_host *head)
 125 {
 126         u32 hash, crc;
 127
 128         if (lh->lh_header.mh_magic != cpu_to_be32(GFS2_MAGIC) ||
 129             lh->lh_header.mh_type != cpu_to_be32(GFS2_METATYPE_LH) ||
 130             (blkno && be32_to_cpu(lh->lh_blkno) != blkno))
 131                 return 1;
 132
 133         hash = crc32(~0, lh, LH_V1_SIZE - 4);
 134         hash = ~crc32_le_shift(hash, 4); /* assume lh_hash is zero */
 135
 136         if (be32_to_cpu(lh->lh_hash) != hash)
 137                 return 1;
 138
 139         crc = crc32c(~0, (void *)lh + LH_V1_SIZE + 4,
 140                      sdp->sd_sb.sb_bsize - LH_V1_SIZE - 4);
 141
 142         if ((lh->lh_crc != 0 && be32_to_cpu(lh->lh_crc) != crc))
 143                 return 1;
 144
 145         head->lh_sequence = be64_to_cpu(lh->lh_sequence);
 146         head->lh_flags = be32_to_cpu(lh->lh_flags);
 147         head->lh_tail = be32_to_cpu(lh->lh_tail);
 148         head->lh_blkno = be32_to_cpu(lh->lh_blkno);
 149
 150         return 0;
 151 }
 152 /**
 153  * get_log_header - read the log header for a given segment
 154  * @jd: the journal
 155  * @blk: the block to look at
 156  * @lh: the log header to return
 157  *
 158  * Read the log header for a given segement in a given journal.  Do a few
 159  * sanity checks on it.
 160  *
 161  * Returns: 0 on success,
 162  *          1 if the header was invalid or incomplete,
 163  *          errno on error
 164  */
 165
 166 static int get_log_header(struct gfs2_jdesc *jd, unsigned int blk,
 167                           struct gfs2_log_header_host *head)
 168 {
 169         struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
 170         struct buffer_head *bh;
 171         int error;
 172
 173         error = gfs2_replay_read_block(jd, blk, &bh);
 174         if (error)
 175                 return error;
 176
 177         error = __get_log_header(sdp, (const struct gfs2_log_header *)bh->b_data,
 178                                  blk, head);
 179         brelse(bh);
 180
 181         return error;
 182 }
 183
 184 /**
 185  * foreach_descriptor - go through the active part of the log
 186  * @jd: the journal
 187  * @start: the first log header in the active region
 188  * @end: the last log header (don't process the contents of this entry))
 189  *
 190  * Call a given function once for every log descriptor in the active
 191  * portion of the log.
 192  *
 193  * Returns: errno
 194  */
 195
 196 static int foreach_descriptor(struct gfs2_jdesc *jd, unsigned int start,
 197                               unsigned int end, int pass)
 198 {
 199         struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
 200         struct buffer_head *bh;
 201         struct gfs2_log_descriptor *ld;
 202         int error = 0;
 203         u32 length;
 204         __be64 *ptr;
 205         unsigned int offset = sizeof(struct gfs2_log_descriptor);
 206         offset += sizeof(__be64) - 1;
 207         offset &= ~(sizeof(__be64) - 1);
 208
 209         while (start != end) {
 210                 error = gfs2_replay_read_block(jd, start, &bh);
 211                 if (error)
 212                         return error;
 213                 if (gfs2_meta_check(sdp, bh)) {
 214                         brelse(bh);
 215                         return -EIO;
 216                 }
 217                 ld = (struct gfs2_log_descriptor *)bh->b_data;
 218                 length = be32_to_cpu(ld->ld_length);
 219
 220                 if (be32_to_cpu(ld->ld_header.mh_type) == GFS2_METATYPE_LH) {
 221                         struct gfs2_log_header_host lh;
 222                         error = get_log_header(jd, start, &lh);
 223                         if (!error) {
 224                                 gfs2_replay_incr_blk(jd, &start);
 225                                 brelse(bh);
 226                                 continue;
 227                         }
 228                         if (error == 1) {
 229                                 gfs2_consist_inode(GFS2_I(jd->jd_inode));
 230                                 error = -EIO;
 231                         }
 232                         brelse(bh);
 233                         return error;
 234                 } else if (gfs2_metatype_check(sdp, bh, GFS2_METATYPE_LD)) {
 235                         brelse(bh);
 236                         return -EIO;
 237                 }
 238                 ptr = (__be64 *)(bh->b_data + offset);
 239                 error = lops_scan_elements(jd, start, ld, ptr, pass);
 240                 if (error) {
 241                         brelse(bh);
 242                         return error;
 243                 }
 244
 245                 while (length--)
 246                         gfs2_replay_incr_blk(jd, &start);
 247
 248                 brelse(bh);
 249         }
 250
 251         return 0;
 252 }
 253
 254 /**
 255  * clean_journal - mark a dirty journal as being clean
 256  * @jd: the journal
 257  * @head: the head journal to start from
 258  *
 259  * Returns: errno
 260  */
 261
 262 static void clean_journal(struct gfs2_jdesc *jd,
 263                           struct gfs2_log_header_host *head)
 264 {
 265         struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
 266
 267         sdp->sd_log_flush_head = head->lh_blkno;
 268         gfs2_replay_incr_blk(jd, &sdp->sd_log_flush_head);
 269         gfs2_write_log_header(sdp, jd, head->lh_sequence + 1, 0,
 270                               GFS2_LOG_HEAD_UNMOUNT | GFS2_LOG_HEAD_RECOVERY,
 271                               REQ_PREFLUSH | REQ_FUA | REQ_META | REQ_SYNC);
 272 }
 273
 274
 275 static void gfs2_recovery_done(struct gfs2_sbd *sdp, unsigned int jid,
 276                                unsigned int message)
 277 {
 278         char env_jid[20];
 279         char env_status[20];
 280         char *envp[] = { env_jid, env_status, NULL };
 281         struct lm_lockstruct *ls = &sdp->sd_lockstruct;
 282
 283         ls->ls_recover_jid_done = jid;
 284         ls->ls_recover_jid_status = message;
 285         sprintf(env_jid, "JID=%u", jid);
 286         sprintf(env_status, "RECOVERY=%s",
 287                 message == LM_RD_SUCCESS ? "Done" : "Failed");
 288         kobject_uevent_env(&sdp->sd_kobj, KOBJ_CHANGE, envp);
 289
 290         if (sdp->sd_lockstruct.ls_ops->lm_recovery_result)
 291                 sdp->sd_lockstruct.ls_ops->lm_recovery_result(sdp, jid, message);
 292 }
 293
 294 void gfs2_recover_func(struct work_struct *work)
 295 {
 296         struct gfs2_jdesc *jd = container_of(work, struct gfs2_jdesc, jd_work);
 297         struct gfs2_inode *ip = GFS2_I(jd->jd_inode);
 298         struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
 299         struct gfs2_log_header_host head;
 300         struct gfs2_holder j_gh, ji_gh, thaw_gh;
 301         ktime_t t_start, t_jlck, t_jhd, t_tlck, t_rep;
 302         int ro = 0;
 303         unsigned int pass;
 304         int error = 0;
 305         int jlocked = 0;
 306
 307         t_start = ktime_get();
 308         if (sdp->sd_args.ar_spectator)
 309                 goto fail;
 310         if (jd->jd_jid != sdp->sd_lockstruct.ls_jid) {
 311                 fs_info(sdp, "jid=%u: Trying to acquire journal lock...\n",
 312                         jd->jd_jid);
 313                 jlocked = 1;
 314                 /* Acquire the journal lock so we can do recovery */
 315
 316                 error = gfs2_glock_nq_num(sdp, jd->jd_jid, &gfs2_journal_glops,
 317                                           LM_ST_EXCLUSIVE,
 318                                           LM_FLAG_NOEXP | LM_FLAG_TRY | GL_NOCACHE,
 319                                           &j_gh);
 320                 switch (error) {
 321                 case 0:
 322                         break;
 323
 324                 case GLR_TRYFAILED:
 325                         fs_info(sdp, "jid=%u: Busy\n", jd->jd_jid);
 326                         error = 0;
 327
 328                 default:
 329                         goto fail;
 330                 };
 331
 332                 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED,
 333                                            LM_FLAG_NOEXP | GL_NOCACHE, &ji_gh);
 334                 if (error)
 335                         goto fail_gunlock_j;
 336         } else {
 337                 fs_info(sdp, "jid=%u, already locked for use\n", jd->jd_jid);
 338         }
 339
 340         t_jlck = ktime_get();
 341         fs_info(sdp, "jid=%u: Looking at journal...\n", jd->jd_jid);
 342
 343         error = gfs2_jdesc_check(jd);
 344         if (error)
 345                 goto fail_gunlock_ji;
 346
 347         error = gfs2_find_jhead(jd, &head);
 348         if (error)
 349                 goto fail_gunlock_ji;
 350         t_jhd = ktime_get();
 351         fs_info(sdp, "jid=%u: Journal head lookup took %lldms\n", jd->jd_jid,
 352                 ktime_ms_delta(t_jhd, t_jlck));
 353
 354         if (!(head.lh_flags & GFS2_LOG_HEAD_UNMOUNT)) {
 355                 fs_info(sdp, "jid=%u: Acquiring the transaction lock...\n",
 356                         jd->jd_jid);
 357
 358                 /* Acquire a shared hold on the freeze lock */
 359
 360                 error = gfs2_glock_nq_init(sdp->sd_freeze_gl, LM_ST_SHARED,
 361                                            LM_FLAG_NOEXP | LM_FLAG_PRIORITY,
 362                                            &thaw_gh);
 363                 if (error)
 364                         goto fail_gunlock_ji;
 365
 366                 if (test_bit(SDF_RORECOVERY, &sdp->sd_flags)) {
 367                         ro = 1;
 368                 } else if (test_bit(SDF_JOURNAL_CHECKED, &sdp->sd_flags)) {
 369                         if (!test_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags))
 370                                 ro = 1;
 371                 } else {
 372                         if (sb_rdonly(sdp->sd_vfs)) {
 373                                 /* check if device itself is read-only */
 374                                 ro = bdev_read_only(sdp->sd_vfs->s_bdev);
 375                                 if (!ro) {
 376                                         fs_info(sdp, "recovery required on "
 377                                                 "read-only filesystem.\n");
 378                                         fs_info(sdp, "write access will be "
 379                                                 "enabled during recovery.\n");
 380                                 }
 381                         }
 382                 }
 383
 384                 if (ro) {
 385                         fs_warn(sdp, "jid=%u: Can't replay: read-only block "
 386                                 "device\n", jd->jd_jid);
 387                         error = -EROFS;
 388                         goto fail_gunlock_thaw;
 389                 }
 390
 391                 t_tlck = ktime_get();
 392                 fs_info(sdp, "jid=%u: Replaying journal...\n", jd->jd_jid);
 393
 394                 for (pass = 0; pass < 2; pass++) {
 395                         lops_before_scan(jd, &head, pass);
 396                         error = foreach_descriptor(jd, head.lh_tail,
 397                                                    head.lh_blkno, pass);
 398                         lops_after_scan(jd, error, pass);
 399                         if (error)
 400                                 goto fail_gunlock_thaw;
 401                 }
 402
 403                 clean_journal(jd, &head);
 404
 405                 gfs2_glock_dq_uninit(&thaw_gh);
 406                 t_rep = ktime_get();
 407                 fs_info(sdp, "jid=%u: Journal replayed in %lldms [jlck:%lldms, "
 408                         "jhead:%lldms, tlck:%lldms, replay:%lldms]\n",
 409                         jd->jd_jid, ktime_ms_delta(t_rep, t_start),
 410                         ktime_ms_delta(t_jlck, t_start),
 411                         ktime_ms_delta(t_jhd, t_jlck),
 412                         ktime_ms_delta(t_tlck, t_jhd),
 413                         ktime_ms_delta(t_rep, t_tlck));
 414         }
 415
 416         gfs2_recovery_done(sdp, jd->jd_jid, LM_RD_SUCCESS);
 417
 418         if (jlocked) {
 419                 gfs2_glock_dq_uninit(&ji_gh);
 420                 gfs2_glock_dq_uninit(&j_gh);
 421         }
 422
 423         fs_info(sdp, "jid=%u: Done\n", jd->jd_jid);
 424         goto done;
 425
 426 fail_gunlock_thaw:
 427         gfs2_glock_dq_uninit(&thaw_gh);
 428 fail_gunlock_ji:
 429         if (jlocked) {
 430                 gfs2_glock_dq_uninit(&ji_gh);
 431 fail_gunlock_j:
 432                 gfs2_glock_dq_uninit(&j_gh);
 433         }
 434
 435         fs_info(sdp, "jid=%u: %s\n", jd->jd_jid, (error) ? "Failed" : "Done");
 436 fail:
 437         jd->jd_recover_error = error;
 438         gfs2_recovery_done(sdp, jd->jd_jid, LM_RD_GAVEUP);
 439 done:
 440         clear_bit(JDF_RECOVERY, &jd->jd_flags);
 441         smp_mb__after_atomic();
 442         wake_up_bit(&jd->jd_flags, JDF_RECOVERY);
 443 }
 444
 445 int gfs2_recover_journal(struct gfs2_jdesc *jd, bool wait)
 446 {
 447         int rv;
 448
 449         if (test_and_set_bit(JDF_RECOVERY, &jd->jd_flags))
 450                 return -EBUSY;
 451
 452         /* we have JDF_RECOVERY, queue should always succeed */
 453         rv = queue_work(gfs_recovery_wq, &jd->jd_work);
 454         BUG_ON(!rv);
 455
 456         if (wait)
 457                 wait_on_bit(&jd->jd_flags, JDF_RECOVERY,
 458                             TASK_UNINTERRUPTIBLE);
 459
 460         return wait ? jd->jd_recover_error : 0;
 461 }
 462