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 19 #include "gfs2.h" 20 #include "incore.h" 21 #include "bmap.h" 22 #include "glock.h" 23 #include "glops.h" 24 #include "log.h" 25 #include "lops.h" 26 #include "meta_io.h" 27 #include "recovery.h" 28 #include "super.h" 29 #include "util.h" 30 #include "dir.h" 31 32 struct workqueue_struct *gfs_recovery_wq; 33 34 int gfs2_replay_read_block(struct gfs2_jdesc *jd, unsigned int blk, 35 struct buffer_head **bh) 36 { 37 struct gfs2_inode *ip = GFS2_I(jd->jd_inode); 38 struct gfs2_glock *gl = ip->i_gl; 39 int new = 0; 40 u64 dblock; 41 u32 extlen; 42 int error; 43 44 error = gfs2_extent_map(&ip->i_inode, blk, &new, &dblock, &extlen); 45 if (error) 46 return error; 47 if (!dblock) { 48 gfs2_consist_inode(ip); 49 return -EIO; 50 } 51 52 *bh = gfs2_meta_ra(gl, dblock, extlen); 53 54 return error; 55 } 56 57 int gfs2_revoke_add(struct gfs2_jdesc *jd, u64 blkno, unsigned int where) 58 { 59 struct list_head *head = &jd->jd_revoke_list; 60 struct gfs2_revoke_replay *rr; 61 int found = 0; 62 63 list_for_each_entry(rr, head, rr_list) { 64 if (rr->rr_blkno == blkno) { 65 found = 1; 66 break; 67 } 68 } 69 70 if (found) { 71 rr->rr_where = where; 72 return 0; 73 } 74 75 rr = kmalloc(sizeof(struct gfs2_revoke_replay), GFP_NOFS); 76 if (!rr) 77 return -ENOMEM; 78 79 rr->rr_blkno = blkno; 80 rr->rr_where = where; 81 list_add(&rr->rr_list, head); 82 83 return 1; 84 } 85 86 int gfs2_revoke_check(struct gfs2_jdesc *jd, u64 blkno, unsigned int where) 87 { 88 struct gfs2_revoke_replay *rr; 89 int wrap, a, b, revoke; 90 int found = 0; 91 92 list_for_each_entry(rr, &jd->jd_revoke_list, rr_list) { 93 if (rr->rr_blkno == blkno) { 94 found = 1; 95 break; 96 } 97 } 98 99 if (!found) 100 return 0; 101 102 wrap = (rr->rr_where < jd->jd_replay_tail); 103 a = (jd->jd_replay_tail < where); 104 b = (where < rr->rr_where); 105 revoke = (wrap) ? (a || b) : (a && b); 106 107 return revoke; 108 } 109 110 void gfs2_revoke_clean(struct gfs2_jdesc *jd) 111 { 112 struct list_head *head = &jd->jd_revoke_list; 113 struct gfs2_revoke_replay *rr; 114 115 while (!list_empty(head)) { 116 rr = list_entry(head->next, struct gfs2_revoke_replay, rr_list); 117 list_del(&rr->rr_list); 118 kfree(rr); 119 } 120 } 121 122 /** 123 * get_log_header - read the log header for a given segment 124 * @jd: the journal 125 * @blk: the block to look at 126 * @lh: the log header to return 127 * 128 * Read the log header for a given segement in a given journal. Do a few 129 * sanity checks on it. 130 * 131 * Returns: 0 on success, 132 * 1 if the header was invalid or incomplete, 133 * errno on error 134 */ 135 136 static int get_log_header(struct gfs2_jdesc *jd, unsigned int blk, 137 struct gfs2_log_header_host *head) 138 { 139 struct gfs2_log_header *lh; 140 struct buffer_head *bh; 141 u32 hash, crc; 142 int error; 143 144 error = gfs2_replay_read_block(jd, blk, &bh); 145 if (error) 146 return error; 147 lh = (void *)bh->b_data; 148 149 hash = crc32(~0, lh, LH_V1_SIZE - 4); 150 hash = ~crc32_le_shift(hash, 4); /* assume lh_hash is zero */ 151 152 crc = crc32c(~0, (void *)lh + LH_V1_SIZE + 4, 153 bh->b_size - LH_V1_SIZE - 4); 154 155 error = lh->lh_header.mh_magic != cpu_to_be32(GFS2_MAGIC) || 156 lh->lh_header.mh_type != cpu_to_be32(GFS2_METATYPE_LH) || 157 be32_to_cpu(lh->lh_blkno) != blk || 158 be32_to_cpu(lh->lh_hash) != hash || 159 (lh->lh_crc != 0 && be32_to_cpu(lh->lh_crc) != crc); 160 161 brelse(bh); 162 163 if (!error) { 164 head->lh_sequence = be64_to_cpu(lh->lh_sequence); 165 head->lh_flags = be32_to_cpu(lh->lh_flags); 166 head->lh_tail = be32_to_cpu(lh->lh_tail); 167 head->lh_blkno = be32_to_cpu(lh->lh_blkno); 168 } 169 return error; 170 } 171 172 /** 173 * find_good_lh - find a good log header 174 * @jd: the journal 175 * @blk: the segment to start searching from 176 * @lh: the log header to fill in 177 * @forward: if true search forward in the log, else search backward 178 * 179 * Call get_log_header() to get a log header for a segment, but if the 180 * segment is bad, either scan forward or backward until we find a good one. 181 * 182 * Returns: errno 183 */ 184 185 static int find_good_lh(struct gfs2_jdesc *jd, unsigned int *blk, 186 struct gfs2_log_header_host *head) 187 { 188 unsigned int orig_blk = *blk; 189 int error; 190 191 for (;;) { 192 error = get_log_header(jd, *blk, head); 193 if (error <= 0) 194 return error; 195 196 if (++*blk == jd->jd_blocks) 197 *blk = 0; 198 199 if (*blk == orig_blk) { 200 gfs2_consist_inode(GFS2_I(jd->jd_inode)); 201 return -EIO; 202 } 203 } 204 } 205 206 /** 207 * jhead_scan - make sure we've found the head of the log 208 * @jd: the journal 209 * @head: this is filled in with the log descriptor of the head 210 * 211 * At this point, seg and lh should be either the head of the log or just 212 * before. Scan forward until we find the head. 213 * 214 * Returns: errno 215 */ 216 217 static int jhead_scan(struct gfs2_jdesc *jd, struct gfs2_log_header_host *head) 218 { 219 unsigned int blk = head->lh_blkno; 220 struct gfs2_log_header_host lh; 221 int error; 222 223 for (;;) { 224 if (++blk == jd->jd_blocks) 225 blk = 0; 226 227 error = get_log_header(jd, blk, &lh); 228 if (error < 0) 229 return error; 230 if (error == 1) 231 continue; 232 233 if (lh.lh_sequence == head->lh_sequence) { 234 gfs2_consist_inode(GFS2_I(jd->jd_inode)); 235 return -EIO; 236 } 237 if (lh.lh_sequence < head->lh_sequence) 238 break; 239 240 *head = lh; 241 } 242 243 return 0; 244 } 245 246 /** 247 * gfs2_find_jhead - find the head of a log 248 * @jd: the journal 249 * @head: the log descriptor for the head of the log is returned here 250 * 251 * Do a binary search of a journal and find the valid log entry with the 252 * highest sequence number. (i.e. the log head) 253 * 254 * Returns: errno 255 */ 256 257 int gfs2_find_jhead(struct gfs2_jdesc *jd, struct gfs2_log_header_host *head) 258 { 259 struct gfs2_log_header_host lh_1, lh_m; 260 u32 blk_1, blk_2, blk_m; 261 int error; 262 263 blk_1 = 0; 264 blk_2 = jd->jd_blocks - 1; 265 266 for (;;) { 267 blk_m = (blk_1 + blk_2) / 2; 268 269 error = find_good_lh(jd, &blk_1, &lh_1); 270 if (error) 271 return error; 272 273 error = find_good_lh(jd, &blk_m, &lh_m); 274 if (error) 275 return error; 276 277 if (blk_1 == blk_m || blk_m == blk_2) 278 break; 279 280 if (lh_1.lh_sequence <= lh_m.lh_sequence) 281 blk_1 = blk_m; 282 else 283 blk_2 = blk_m; 284 } 285 286 error = jhead_scan(jd, &lh_1); 287 if (error) 288 return error; 289 290 *head = lh_1; 291 292 return error; 293 } 294 295 /** 296 * foreach_descriptor - go through the active part of the log 297 * @jd: the journal 298 * @start: the first log header in the active region 299 * @end: the last log header (don't process the contents of this entry)) 300 * 301 * Call a given function once for every log descriptor in the active 302 * portion of the log. 303 * 304 * Returns: errno 305 */ 306 307 static int foreach_descriptor(struct gfs2_jdesc *jd, unsigned int start, 308 unsigned int end, int pass) 309 { 310 struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode); 311 struct buffer_head *bh; 312 struct gfs2_log_descriptor *ld; 313 int error = 0; 314 u32 length; 315 __be64 *ptr; 316 unsigned int offset = sizeof(struct gfs2_log_descriptor); 317 offset += sizeof(__be64) - 1; 318 offset &= ~(sizeof(__be64) - 1); 319 320 while (start != end) { 321 error = gfs2_replay_read_block(jd, start, &bh); 322 if (error) 323 return error; 324 if (gfs2_meta_check(sdp, bh)) { 325 brelse(bh); 326 return -EIO; 327 } 328 ld = (struct gfs2_log_descriptor *)bh->b_data; 329 length = be32_to_cpu(ld->ld_length); 330 331 if (be32_to_cpu(ld->ld_header.mh_type) == GFS2_METATYPE_LH) { 332 struct gfs2_log_header_host lh; 333 error = get_log_header(jd, start, &lh); 334 if (!error) { 335 gfs2_replay_incr_blk(jd, &start); 336 brelse(bh); 337 continue; 338 } 339 if (error == 1) { 340 gfs2_consist_inode(GFS2_I(jd->jd_inode)); 341 error = -EIO; 342 } 343 brelse(bh); 344 return error; 345 } else if (gfs2_metatype_check(sdp, bh, GFS2_METATYPE_LD)) { 346 brelse(bh); 347 return -EIO; 348 } 349 ptr = (__be64 *)(bh->b_data + offset); 350 error = lops_scan_elements(jd, start, ld, ptr, pass); 351 if (error) { 352 brelse(bh); 353 return error; 354 } 355 356 while (length--) 357 gfs2_replay_incr_blk(jd, &start); 358 359 brelse(bh); 360 } 361 362 return 0; 363 } 364 365 /** 366 * clean_journal - mark a dirty journal as being clean 367 * @jd: the journal 368 * @head: the head journal to start from 369 * 370 * Returns: errno 371 */ 372 373 static void clean_journal(struct gfs2_jdesc *jd, 374 struct gfs2_log_header_host *head) 375 { 376 struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode); 377 378 sdp->sd_log_flush_head = head->lh_blkno; 379 gfs2_replay_incr_blk(jd, &sdp->sd_log_flush_head); 380 gfs2_write_log_header(sdp, jd, head->lh_sequence + 1, 0, 381 GFS2_LOG_HEAD_UNMOUNT | GFS2_LOG_HEAD_RECOVERY, 382 REQ_PREFLUSH | REQ_FUA | REQ_META | REQ_SYNC); 383 } 384 385 386 static void gfs2_recovery_done(struct gfs2_sbd *sdp, unsigned int jid, 387 unsigned int message) 388 { 389 char env_jid[20]; 390 char env_status[20]; 391 char *envp[] = { env_jid, env_status, NULL }; 392 struct lm_lockstruct *ls = &sdp->sd_lockstruct; 393 394 ls->ls_recover_jid_done = jid; 395 ls->ls_recover_jid_status = message; 396 sprintf(env_jid, "JID=%u", jid); 397 sprintf(env_status, "RECOVERY=%s", 398 message == LM_RD_SUCCESS ? "Done" : "Failed"); 399 kobject_uevent_env(&sdp->sd_kobj, KOBJ_CHANGE, envp); 400 401 if (sdp->sd_lockstruct.ls_ops->lm_recovery_result) 402 sdp->sd_lockstruct.ls_ops->lm_recovery_result(sdp, jid, message); 403 } 404 405 void gfs2_recover_func(struct work_struct *work) 406 { 407 struct gfs2_jdesc *jd = container_of(work, struct gfs2_jdesc, jd_work); 408 struct gfs2_inode *ip = GFS2_I(jd->jd_inode); 409 struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode); 410 struct gfs2_log_header_host head; 411 struct gfs2_holder j_gh, ji_gh, thaw_gh; 412 unsigned long t; 413 int ro = 0; 414 unsigned int pass; 415 int error; 416 int jlocked = 0; 417 418 if (sdp->sd_args.ar_spectator || 419 (jd->jd_jid != sdp->sd_lockstruct.ls_jid)) { 420 fs_info(sdp, "jid=%u: Trying to acquire journal lock...\n", 421 jd->jd_jid); 422 jlocked = 1; 423 /* Acquire the journal lock so we can do recovery */ 424 425 error = gfs2_glock_nq_num(sdp, jd->jd_jid, &gfs2_journal_glops, 426 LM_ST_EXCLUSIVE, 427 LM_FLAG_NOEXP | LM_FLAG_TRY | GL_NOCACHE, 428 &j_gh); 429 switch (error) { 430 case 0: 431 break; 432 433 case GLR_TRYFAILED: 434 fs_info(sdp, "jid=%u: Busy\n", jd->jd_jid); 435 error = 0; 436 437 default: 438 goto fail; 439 }; 440 441 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 442 LM_FLAG_NOEXP | GL_NOCACHE, &ji_gh); 443 if (error) 444 goto fail_gunlock_j; 445 } else { 446 fs_info(sdp, "jid=%u, already locked for use\n", jd->jd_jid); 447 } 448 449 fs_info(sdp, "jid=%u: Looking at journal...\n", jd->jd_jid); 450 451 error = gfs2_jdesc_check(jd); 452 if (error) 453 goto fail_gunlock_ji; 454 455 error = gfs2_find_jhead(jd, &head); 456 if (error) 457 goto fail_gunlock_ji; 458 459 if (!(head.lh_flags & GFS2_LOG_HEAD_UNMOUNT)) { 460 fs_info(sdp, "jid=%u: Acquiring the transaction lock...\n", 461 jd->jd_jid); 462 463 t = jiffies; 464 465 /* Acquire a shared hold on the freeze lock */ 466 467 error = gfs2_glock_nq_init(sdp->sd_freeze_gl, LM_ST_SHARED, 468 LM_FLAG_NOEXP | LM_FLAG_PRIORITY, 469 &thaw_gh); 470 if (error) 471 goto fail_gunlock_ji; 472 473 if (test_bit(SDF_RORECOVERY, &sdp->sd_flags)) { 474 ro = 1; 475 } else if (test_bit(SDF_JOURNAL_CHECKED, &sdp->sd_flags)) { 476 if (!test_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags)) 477 ro = 1; 478 } else { 479 if (sb_rdonly(sdp->sd_vfs)) { 480 /* check if device itself is read-only */ 481 ro = bdev_read_only(sdp->sd_vfs->s_bdev); 482 if (!ro) { 483 fs_info(sdp, "recovery required on " 484 "read-only filesystem.\n"); 485 fs_info(sdp, "write access will be " 486 "enabled during recovery.\n"); 487 } 488 } 489 } 490 491 if (ro) { 492 fs_warn(sdp, "jid=%u: Can't replay: read-only block " 493 "device\n", jd->jd_jid); 494 error = -EROFS; 495 goto fail_gunlock_thaw; 496 } 497 498 fs_info(sdp, "jid=%u: Replaying journal...\n", jd->jd_jid); 499 500 for (pass = 0; pass < 2; pass++) { 501 lops_before_scan(jd, &head, pass); 502 error = foreach_descriptor(jd, head.lh_tail, 503 head.lh_blkno, pass); 504 lops_after_scan(jd, error, pass); 505 if (error) 506 goto fail_gunlock_thaw; 507 } 508 509 clean_journal(jd, &head); 510 511 gfs2_glock_dq_uninit(&thaw_gh); 512 t = DIV_ROUND_UP(jiffies - t, HZ); 513 fs_info(sdp, "jid=%u: Journal replayed in %lus\n", 514 jd->jd_jid, t); 515 } 516 517 gfs2_recovery_done(sdp, jd->jd_jid, LM_RD_SUCCESS); 518 519 if (jlocked) { 520 gfs2_glock_dq_uninit(&ji_gh); 521 gfs2_glock_dq_uninit(&j_gh); 522 } 523 524 fs_info(sdp, "jid=%u: Done\n", jd->jd_jid); 525 goto done; 526 527 fail_gunlock_thaw: 528 gfs2_glock_dq_uninit(&thaw_gh); 529 fail_gunlock_ji: 530 if (jlocked) { 531 gfs2_glock_dq_uninit(&ji_gh); 532 fail_gunlock_j: 533 gfs2_glock_dq_uninit(&j_gh); 534 } 535 536 fs_info(sdp, "jid=%u: %s\n", jd->jd_jid, (error) ? "Failed" : "Done"); 537 fail: 538 jd->jd_recover_error = error; 539 gfs2_recovery_done(sdp, jd->jd_jid, LM_RD_GAVEUP); 540 done: 541 clear_bit(JDF_RECOVERY, &jd->jd_flags); 542 smp_mb__after_atomic(); 543 wake_up_bit(&jd->jd_flags, JDF_RECOVERY); 544 } 545 546 int gfs2_recover_journal(struct gfs2_jdesc *jd, bool wait) 547 { 548 int rv; 549 550 if (test_and_set_bit(JDF_RECOVERY, &jd->jd_flags)) 551 return -EBUSY; 552 553 /* we have JDF_RECOVERY, queue should always succeed */ 554 rv = queue_work(gfs_recovery_wq, &jd->jd_work); 555 BUG_ON(!rv); 556 557 if (wait) 558 wait_on_bit(&jd->jd_flags, JDF_RECOVERY, 559 TASK_UNINTERRUPTIBLE); 560 561 return wait ? jd->jd_recover_error : 0; 562 } 563 564