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, u32 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         u32 lblock = head->lh_blkno;
 267
 268         gfs2_replay_incr_blk(jd, &lblock);
 269         if (jd->jd_jid == sdp->sd_lockstruct.ls_jid)
 270                 sdp->sd_log_flush_head = lblock;
 271         gfs2_write_log_header(sdp, jd, head->lh_sequence + 1, 0, lblock,
 272                               GFS2_LOG_HEAD_UNMOUNT | GFS2_LOG_HEAD_RECOVERY,
 273                               REQ_PREFLUSH | REQ_FUA | REQ_META | REQ_SYNC);
 274 }
 275
 276
 277 static void gfs2_recovery_done(struct gfs2_sbd *sdp, unsigned int jid,
 278                                unsigned int message)
 279 {
 280         char env_jid[20];
 281         char env_status[20];
 282         char *envp[] = { env_jid, env_status, NULL };
 283         struct lm_lockstruct *ls = &sdp->sd_lockstruct;
 284
 285         ls->ls_recover_jid_done = jid;
 286         ls->ls_recover_jid_status = message;
 287         sprintf(env_jid, "JID=%u", jid);
 288         sprintf(env_status, "RECOVERY=%s",
 289                 message == LM_RD_SUCCESS ? "Done" : "Failed");
 290         kobject_uevent_env(&sdp->sd_kobj, KOBJ_CHANGE, envp);
 291
 292         if (sdp->sd_lockstruct.ls_ops->lm_recovery_result)
 293                 sdp->sd_lockstruct.ls_ops->lm_recovery_result(sdp, jid, message);
 294 }
 295
 296 void gfs2_recover_func(struct work_struct *work)
 297 {
 298         struct gfs2_jdesc *jd = container_of(work, struct gfs2_jdesc, jd_work);
 299         struct gfs2_inode *ip = GFS2_I(jd->jd_inode);
 300         struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
 301         struct gfs2_log_header_host head;
 302         struct gfs2_holder j_gh, ji_gh, thaw_gh;
 303         ktime_t t_start, t_jlck, t_jhd, t_tlck, t_rep;
 304         int ro = 0;
 305         unsigned int pass;
 306         int error = 0;
 307         int jlocked = 0;
 308
 309         t_start = ktime_get();
 310         if (sdp->sd_args.ar_spectator)
 311                 goto fail;
 312         if (jd->jd_jid != sdp->sd_lockstruct.ls_jid) {
 313                 fs_info(sdp, "jid=%u: Trying to acquire journal lock...\n",
 314                         jd->jd_jid);
 315                 jlocked = 1;
 316                 /* Acquire the journal lock so we can do recovery */
 317
 318                 error = gfs2_glock_nq_num(sdp, jd->jd_jid, &gfs2_journal_glops,
 319                                           LM_ST_EXCLUSIVE,
 320                                           LM_FLAG_NOEXP | LM_FLAG_TRY | GL_NOCACHE,
 321                                           &j_gh);
 322                 switch (error) {
 323                 case 0:
 324                         break;
 325
 326                 case GLR_TRYFAILED:
 327                         fs_info(sdp, "jid=%u: Busy\n", jd->jd_jid);
 328                         error = 0;
 329
 330                 default:
 331                         goto fail;
 332                 };
 333
 334                 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED,
 335                                            LM_FLAG_NOEXP | GL_NOCACHE, &ji_gh);
 336                 if (error)
 337                         goto fail_gunlock_j;
 338         } else {
 339                 fs_info(sdp, "jid=%u, already locked for use\n", jd->jd_jid);
 340         }
 341
 342         t_jlck = ktime_get();
 343         fs_info(sdp, "jid=%u: Looking at journal...\n", jd->jd_jid);
 344
 345         error = gfs2_jdesc_check(jd);
 346         if (error)
 347                 goto fail_gunlock_ji;
 348
 349         error = gfs2_find_jhead(jd, &head, true);
 350         if (error)
 351                 goto fail_gunlock_ji;
 352         t_jhd = ktime_get();
 353         fs_info(sdp, "jid=%u: Journal head lookup took %lldms\n", jd->jd_jid,
 354                 ktime_ms_delta(t_jhd, t_jlck));
 355
 356         if (!(head.lh_flags & GFS2_LOG_HEAD_UNMOUNT)) {
 357                 fs_info(sdp, "jid=%u: Acquiring the transaction lock...\n",
 358                         jd->jd_jid);
 359
 360                 /* Acquire a shared hold on the freeze lock */
 361
 362                 error = gfs2_glock_nq_init(sdp->sd_freeze_gl, LM_ST_SHARED,
 363                                            LM_FLAG_NOEXP | LM_FLAG_PRIORITY,
 364                                            &thaw_gh);
 365                 if (error)
 366                         goto fail_gunlock_ji;
 367
 368                 if (test_bit(SDF_RORECOVERY, &sdp->sd_flags)) {
 369                         ro = 1;
 370                 } else if (test_bit(SDF_JOURNAL_CHECKED, &sdp->sd_flags)) {
 371                         if (!test_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags))
 372                                 ro = 1;
 373                 } else {
 374                         if (sb_rdonly(sdp->sd_vfs)) {
 375                                 /* check if device itself is read-only */
 376                                 ro = bdev_read_only(sdp->sd_vfs->s_bdev);
 377                                 if (!ro) {
 378                                         fs_info(sdp, "recovery required on "
 379                                                 "read-only filesystem.\n");
 380                                         fs_info(sdp, "write access will be "
 381                                                 "enabled during recovery.\n");
 382                                 }
 383                         }
 384                 }
 385
 386                 if (ro) {
 387                         fs_warn(sdp, "jid=%u: Can't replay: read-only block "
 388                                 "device\n", jd->jd_jid);
 389                         error = -EROFS;
 390                         goto fail_gunlock_thaw;
 391                 }
 392
 393                 t_tlck = ktime_get();
 394                 fs_info(sdp, "jid=%u: Replaying journal...\n", jd->jd_jid);
 395
 396                 for (pass = 0; pass < 2; pass++) {
 397                         lops_before_scan(jd, &head, pass);
 398                         error = foreach_descriptor(jd, head.lh_tail,
 399                                                    head.lh_blkno, pass);
 400                         lops_after_scan(jd, error, pass);
 401                         if (error)
 402                                 goto fail_gunlock_thaw;
 403                 }
 404
 405                 clean_journal(jd, &head);
 406
 407                 gfs2_glock_dq_uninit(&thaw_gh);
 408                 t_rep = ktime_get();
 409                 fs_info(sdp, "jid=%u: Journal replayed in %lldms [jlck:%lldms, "
 410                         "jhead:%lldms, tlck:%lldms, replay:%lldms]\n",
 411                         jd->jd_jid, ktime_ms_delta(t_rep, t_start),
 412                         ktime_ms_delta(t_jlck, t_start),
 413                         ktime_ms_delta(t_jhd, t_jlck),
 414                         ktime_ms_delta(t_tlck, t_jhd),
 415                         ktime_ms_delta(t_rep, t_tlck));
 416         }
 417
 418         gfs2_recovery_done(sdp, jd->jd_jid, LM_RD_SUCCESS);
 419
 420         if (jlocked) {
 421                 gfs2_glock_dq_uninit(&ji_gh);
 422                 gfs2_glock_dq_uninit(&j_gh);
 423         }
 424
 425         fs_info(sdp, "jid=%u: Done\n", jd->jd_jid);
 426         goto done;
 427
 428 fail_gunlock_thaw:
 429         gfs2_glock_dq_uninit(&thaw_gh);
 430 fail_gunlock_ji:
 431         if (jlocked) {
 432                 gfs2_glock_dq_uninit(&ji_gh);
 433 fail_gunlock_j:
 434                 gfs2_glock_dq_uninit(&j_gh);
 435         }
 436
 437         fs_info(sdp, "jid=%u: %s\n", jd->jd_jid, (error) ? "Failed" : "Done");
 438 fail:
 439         jd->jd_recover_error = error;
 440         gfs2_recovery_done(sdp, jd->jd_jid, LM_RD_GAVEUP);
 441 done:
 442         clear_bit(JDF_RECOVERY, &jd->jd_flags);
 443         smp_mb__after_atomic();
 444         wake_up_bit(&jd->jd_flags, JDF_RECOVERY);
 445 }
 446
 447 int gfs2_recover_journal(struct gfs2_jdesc *jd, bool wait)
 448 {
 449         int rv;
 450
 451         if (test_and_set_bit(JDF_RECOVERY, &jd->jd_flags))
 452                 return -EBUSY;
 453
 454         /* we have JDF_RECOVERY, queue should always succeed */
 455         rv = queue_work(gfs_recovery_wq, &jd->jd_work);
 456         BUG_ON(!rv);
 457
 458         if (wait)
 459                 wait_on_bit(&jd->jd_flags, JDF_RECOVERY,
 460                             TASK_UNINTERRUPTIBLE);
 461
 462         return wait ? jd->jd_recover_error : 0;
 463 }
 464