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 18 #include "gfs2.h" 19 #include "incore.h" 20 #include "bmap.h" 21 #include "glock.h" 22 #include "glops.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_entry(head->next, struct gfs2_revoke_replay, rr_list); 115 list_del(&rr->rr_list); 116 kfree(rr); 117 } 118 } 119 120 static int gfs2_log_header_in(struct gfs2_log_header_host *lh, const void *buf) 121 { 122 const struct gfs2_log_header *str = buf; 123 124 if (str->lh_header.mh_magic != cpu_to_be32(GFS2_MAGIC) || 125 str->lh_header.mh_type != cpu_to_be32(GFS2_METATYPE_LH)) 126 return 1; 127 128 lh->lh_sequence = be64_to_cpu(str->lh_sequence); 129 lh->lh_flags = be32_to_cpu(str->lh_flags); 130 lh->lh_tail = be32_to_cpu(str->lh_tail); 131 lh->lh_blkno = be32_to_cpu(str->lh_blkno); 132 lh->lh_hash = be32_to_cpu(str->lh_hash); 133 return 0; 134 } 135 136 /** 137 * get_log_header - read the log header for a given segment 138 * @jd: the journal 139 * @blk: the block to look at 140 * @lh: the log header to return 141 * 142 * Read the log header for a given segement in a given journal. Do a few 143 * sanity checks on it. 144 * 145 * Returns: 0 on success, 146 * 1 if the header was invalid or incomplete, 147 * errno on error 148 */ 149 150 static int get_log_header(struct gfs2_jdesc *jd, unsigned int blk, 151 struct gfs2_log_header_host *head) 152 { 153 struct buffer_head *bh; 154 struct gfs2_log_header_host uninitialized_var(lh); 155 const u32 nothing = 0; 156 u32 hash; 157 int error; 158 159 error = gfs2_replay_read_block(jd, blk, &bh); 160 if (error) 161 return error; 162 163 hash = crc32_le((u32)~0, bh->b_data, sizeof(struct gfs2_log_header) - 164 sizeof(u32)); 165 hash = crc32_le(hash, (unsigned char const *)¬hing, sizeof(nothing)); 166 hash ^= (u32)~0; 167 error = gfs2_log_header_in(&lh, bh->b_data); 168 brelse(bh); 169 170 if (error || lh.lh_blkno != blk || lh.lh_hash != hash) 171 return 1; 172 173 *head = lh; 174 175 return 0; 176 } 177 178 /** 179 * find_good_lh - find a good log header 180 * @jd: the journal 181 * @blk: the segment to start searching from 182 * @lh: the log header to fill in 183 * @forward: if true search forward in the log, else search backward 184 * 185 * Call get_log_header() to get a log header for a segment, but if the 186 * segment is bad, either scan forward or backward until we find a good one. 187 * 188 * Returns: errno 189 */ 190 191 static int find_good_lh(struct gfs2_jdesc *jd, unsigned int *blk, 192 struct gfs2_log_header_host *head) 193 { 194 unsigned int orig_blk = *blk; 195 int error; 196 197 for (;;) { 198 error = get_log_header(jd, *blk, head); 199 if (error <= 0) 200 return error; 201 202 if (++*blk == jd->jd_blocks) 203 *blk = 0; 204 205 if (*blk == orig_blk) { 206 gfs2_consist_inode(GFS2_I(jd->jd_inode)); 207 return -EIO; 208 } 209 } 210 } 211 212 /** 213 * jhead_scan - make sure we've found the head of the log 214 * @jd: the journal 215 * @head: this is filled in with the log descriptor of the head 216 * 217 * At this point, seg and lh should be either the head of the log or just 218 * before. Scan forward until we find the head. 219 * 220 * Returns: errno 221 */ 222 223 static int jhead_scan(struct gfs2_jdesc *jd, struct gfs2_log_header_host *head) 224 { 225 unsigned int blk = head->lh_blkno; 226 struct gfs2_log_header_host lh; 227 int error; 228 229 for (;;) { 230 if (++blk == jd->jd_blocks) 231 blk = 0; 232 233 error = get_log_header(jd, blk, &lh); 234 if (error < 0) 235 return error; 236 if (error == 1) 237 continue; 238 239 if (lh.lh_sequence == head->lh_sequence) { 240 gfs2_consist_inode(GFS2_I(jd->jd_inode)); 241 return -EIO; 242 } 243 if (lh.lh_sequence < head->lh_sequence) 244 break; 245 246 *head = lh; 247 } 248 249 return 0; 250 } 251 252 /** 253 * gfs2_find_jhead - find the head of a log 254 * @jd: the journal 255 * @head: the log descriptor for the head of the log is returned here 256 * 257 * Do a binary search of a journal and find the valid log entry with the 258 * highest sequence number. (i.e. the log head) 259 * 260 * Returns: errno 261 */ 262 263 int gfs2_find_jhead(struct gfs2_jdesc *jd, struct gfs2_log_header_host *head) 264 { 265 struct gfs2_log_header_host lh_1, lh_m; 266 u32 blk_1, blk_2, blk_m; 267 int error; 268 269 blk_1 = 0; 270 blk_2 = jd->jd_blocks - 1; 271 272 for (;;) { 273 blk_m = (blk_1 + blk_2) / 2; 274 275 error = find_good_lh(jd, &blk_1, &lh_1); 276 if (error) 277 return error; 278 279 error = find_good_lh(jd, &blk_m, &lh_m); 280 if (error) 281 return error; 282 283 if (blk_1 == blk_m || blk_m == blk_2) 284 break; 285 286 if (lh_1.lh_sequence <= lh_m.lh_sequence) 287 blk_1 = blk_m; 288 else 289 blk_2 = blk_m; 290 } 291 292 error = jhead_scan(jd, &lh_1); 293 if (error) 294 return error; 295 296 *head = lh_1; 297 298 return error; 299 } 300 301 /** 302 * foreach_descriptor - go through the active part of the log 303 * @jd: the journal 304 * @start: the first log header in the active region 305 * @end: the last log header (don't process the contents of this entry)) 306 * 307 * Call a given function once for every log descriptor in the active 308 * portion of the log. 309 * 310 * Returns: errno 311 */ 312 313 static int foreach_descriptor(struct gfs2_jdesc *jd, unsigned int start, 314 unsigned int end, int pass) 315 { 316 struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode); 317 struct buffer_head *bh; 318 struct gfs2_log_descriptor *ld; 319 int error = 0; 320 u32 length; 321 __be64 *ptr; 322 unsigned int offset = sizeof(struct gfs2_log_descriptor); 323 offset += sizeof(__be64) - 1; 324 offset &= ~(sizeof(__be64) - 1); 325 326 while (start != end) { 327 error = gfs2_replay_read_block(jd, start, &bh); 328 if (error) 329 return error; 330 if (gfs2_meta_check(sdp, bh)) { 331 brelse(bh); 332 return -EIO; 333 } 334 ld = (struct gfs2_log_descriptor *)bh->b_data; 335 length = be32_to_cpu(ld->ld_length); 336 337 if (be32_to_cpu(ld->ld_header.mh_type) == GFS2_METATYPE_LH) { 338 struct gfs2_log_header_host lh; 339 error = get_log_header(jd, start, &lh); 340 if (!error) { 341 gfs2_replay_incr_blk(sdp, &start); 342 brelse(bh); 343 continue; 344 } 345 if (error == 1) { 346 gfs2_consist_inode(GFS2_I(jd->jd_inode)); 347 error = -EIO; 348 } 349 brelse(bh); 350 return error; 351 } else if (gfs2_metatype_check(sdp, bh, GFS2_METATYPE_LD)) { 352 brelse(bh); 353 return -EIO; 354 } 355 ptr = (__be64 *)(bh->b_data + offset); 356 error = lops_scan_elements(jd, start, ld, ptr, pass); 357 if (error) { 358 brelse(bh); 359 return error; 360 } 361 362 while (length--) 363 gfs2_replay_incr_blk(sdp, &start); 364 365 brelse(bh); 366 } 367 368 return 0; 369 } 370 371 /** 372 * clean_journal - mark a dirty journal as being clean 373 * @sdp: the filesystem 374 * @jd: the journal 375 * @gl: the journal's glock 376 * @head: the head journal to start from 377 * 378 * Returns: errno 379 */ 380 381 static int clean_journal(struct gfs2_jdesc *jd, struct gfs2_log_header_host *head) 382 { 383 struct gfs2_inode *ip = GFS2_I(jd->jd_inode); 384 struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode); 385 unsigned int lblock; 386 struct gfs2_log_header *lh; 387 u32 hash; 388 struct buffer_head *bh; 389 int error; 390 struct buffer_head bh_map = { .b_state = 0, .b_blocknr = 0 }; 391 392 lblock = head->lh_blkno; 393 gfs2_replay_incr_blk(sdp, &lblock); 394 bh_map.b_size = 1 << ip->i_inode.i_blkbits; 395 error = gfs2_block_map(&ip->i_inode, lblock, &bh_map, 0); 396 if (error) 397 return error; 398 if (!bh_map.b_blocknr) { 399 gfs2_consist_inode(ip); 400 return -EIO; 401 } 402 403 bh = sb_getblk(sdp->sd_vfs, bh_map.b_blocknr); 404 lock_buffer(bh); 405 memset(bh->b_data, 0, bh->b_size); 406 set_buffer_uptodate(bh); 407 clear_buffer_dirty(bh); 408 unlock_buffer(bh); 409 410 lh = (struct gfs2_log_header *)bh->b_data; 411 memset(lh, 0, sizeof(struct gfs2_log_header)); 412 lh->lh_header.mh_magic = cpu_to_be32(GFS2_MAGIC); 413 lh->lh_header.mh_type = cpu_to_be32(GFS2_METATYPE_LH); 414 lh->lh_header.__pad0 = cpu_to_be64(0); 415 lh->lh_header.mh_format = cpu_to_be32(GFS2_FORMAT_LH); 416 lh->lh_header.mh_jid = cpu_to_be32(sdp->sd_jdesc->jd_jid); 417 lh->lh_sequence = cpu_to_be64(head->lh_sequence + 1); 418 lh->lh_flags = cpu_to_be32(GFS2_LOG_HEAD_UNMOUNT); 419 lh->lh_blkno = cpu_to_be32(lblock); 420 hash = gfs2_disk_hash((const char *)lh, sizeof(struct gfs2_log_header)); 421 lh->lh_hash = cpu_to_be32(hash); 422 423 set_buffer_dirty(bh); 424 if (sync_dirty_buffer(bh)) 425 gfs2_io_error_bh(sdp, bh); 426 brelse(bh); 427 428 return error; 429 } 430 431 432 static void gfs2_recovery_done(struct gfs2_sbd *sdp, unsigned int jid, 433 unsigned int message) 434 { 435 char env_jid[20]; 436 char env_status[20]; 437 char *envp[] = { env_jid, env_status, NULL }; 438 struct lm_lockstruct *ls = &sdp->sd_lockstruct; 439 440 ls->ls_recover_jid_done = jid; 441 ls->ls_recover_jid_status = message; 442 sprintf(env_jid, "JID=%u", jid); 443 sprintf(env_status, "RECOVERY=%s", 444 message == LM_RD_SUCCESS ? "Done" : "Failed"); 445 kobject_uevent_env(&sdp->sd_kobj, KOBJ_CHANGE, envp); 446 447 if (sdp->sd_lockstruct.ls_ops->lm_recovery_result) 448 sdp->sd_lockstruct.ls_ops->lm_recovery_result(sdp, jid, message); 449 } 450 451 void gfs2_recover_func(struct work_struct *work) 452 { 453 struct gfs2_jdesc *jd = container_of(work, struct gfs2_jdesc, jd_work); 454 struct gfs2_inode *ip = GFS2_I(jd->jd_inode); 455 struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode); 456 struct gfs2_log_header_host head; 457 struct gfs2_holder j_gh, ji_gh, thaw_gh; 458 unsigned long t; 459 int ro = 0; 460 unsigned int pass; 461 int error; 462 int jlocked = 0; 463 464 if (sdp->sd_args.ar_spectator || 465 (jd->jd_jid != sdp->sd_lockstruct.ls_jid)) { 466 fs_info(sdp, "jid=%u: Trying to acquire journal lock...\n", 467 jd->jd_jid); 468 jlocked = 1; 469 /* Acquire the journal lock so we can do recovery */ 470 471 error = gfs2_glock_nq_num(sdp, jd->jd_jid, &gfs2_journal_glops, 472 LM_ST_EXCLUSIVE, 473 LM_FLAG_NOEXP | LM_FLAG_TRY | GL_NOCACHE, 474 &j_gh); 475 switch (error) { 476 case 0: 477 break; 478 479 case GLR_TRYFAILED: 480 fs_info(sdp, "jid=%u: Busy\n", jd->jd_jid); 481 error = 0; 482 483 default: 484 goto fail; 485 }; 486 487 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 488 LM_FLAG_NOEXP | GL_NOCACHE, &ji_gh); 489 if (error) 490 goto fail_gunlock_j; 491 } else { 492 fs_info(sdp, "jid=%u, already locked for use\n", jd->jd_jid); 493 } 494 495 fs_info(sdp, "jid=%u: Looking at journal...\n", jd->jd_jid); 496 497 error = gfs2_jdesc_check(jd); 498 if (error) 499 goto fail_gunlock_ji; 500 501 error = gfs2_find_jhead(jd, &head); 502 if (error) 503 goto fail_gunlock_ji; 504 505 if (!(head.lh_flags & GFS2_LOG_HEAD_UNMOUNT)) { 506 fs_info(sdp, "jid=%u: Acquiring the transaction lock...\n", 507 jd->jd_jid); 508 509 t = jiffies; 510 511 /* Acquire a shared hold on the freeze lock */ 512 513 error = gfs2_glock_nq_init(sdp->sd_freeze_gl, LM_ST_SHARED, 514 LM_FLAG_NOEXP | LM_FLAG_PRIORITY, 515 &thaw_gh); 516 if (error) 517 goto fail_gunlock_ji; 518 519 if (test_bit(SDF_RORECOVERY, &sdp->sd_flags)) { 520 ro = 1; 521 } else if (test_bit(SDF_JOURNAL_CHECKED, &sdp->sd_flags)) { 522 if (!test_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags)) 523 ro = 1; 524 } else { 525 if (sdp->sd_vfs->s_flags & MS_RDONLY) { 526 /* check if device itself is read-only */ 527 ro = bdev_read_only(sdp->sd_vfs->s_bdev); 528 if (!ro) { 529 fs_info(sdp, "recovery required on " 530 "read-only filesystem.\n"); 531 fs_info(sdp, "write access will be " 532 "enabled during recovery.\n"); 533 } 534 } 535 } 536 537 if (ro) { 538 fs_warn(sdp, "jid=%u: Can't replay: read-only block " 539 "device\n", jd->jd_jid); 540 error = -EROFS; 541 goto fail_gunlock_thaw; 542 } 543 544 fs_info(sdp, "jid=%u: Replaying journal...\n", jd->jd_jid); 545 546 for (pass = 0; pass < 2; pass++) { 547 lops_before_scan(jd, &head, pass); 548 error = foreach_descriptor(jd, head.lh_tail, 549 head.lh_blkno, pass); 550 lops_after_scan(jd, error, pass); 551 if (error) 552 goto fail_gunlock_thaw; 553 } 554 555 error = clean_journal(jd, &head); 556 if (error) 557 goto fail_gunlock_thaw; 558 559 gfs2_glock_dq_uninit(&thaw_gh); 560 t = DIV_ROUND_UP(jiffies - t, HZ); 561 fs_info(sdp, "jid=%u: Journal replayed in %lus\n", 562 jd->jd_jid, t); 563 } 564 565 gfs2_recovery_done(sdp, jd->jd_jid, LM_RD_SUCCESS); 566 567 if (jlocked) { 568 gfs2_glock_dq_uninit(&ji_gh); 569 gfs2_glock_dq_uninit(&j_gh); 570 } 571 572 fs_info(sdp, "jid=%u: Done\n", jd->jd_jid); 573 goto done; 574 575 fail_gunlock_thaw: 576 gfs2_glock_dq_uninit(&thaw_gh); 577 fail_gunlock_ji: 578 if (jlocked) { 579 gfs2_glock_dq_uninit(&ji_gh); 580 fail_gunlock_j: 581 gfs2_glock_dq_uninit(&j_gh); 582 } 583 584 fs_info(sdp, "jid=%u: %s\n", jd->jd_jid, (error) ? "Failed" : "Done"); 585 fail: 586 jd->jd_recover_error = error; 587 gfs2_recovery_done(sdp, jd->jd_jid, LM_RD_GAVEUP); 588 done: 589 clear_bit(JDF_RECOVERY, &jd->jd_flags); 590 smp_mb__after_atomic(); 591 wake_up_bit(&jd->jd_flags, JDF_RECOVERY); 592 } 593 594 int gfs2_recover_journal(struct gfs2_jdesc *jd, bool wait) 595 { 596 int rv; 597 598 if (test_and_set_bit(JDF_RECOVERY, &jd->jd_flags)) 599 return -EBUSY; 600 601 /* we have JDF_RECOVERY, queue should always succeed */ 602 rv = queue_work(gfs_recovery_wq, &jd->jd_work); 603 BUG_ON(!rv); 604 605 if (wait) 606 wait_on_bit(&jd->jd_flags, JDF_RECOVERY, 607 TASK_UNINTERRUPTIBLE); 608 609 return wait ? jd->jd_recover_error : 0; 610 } 611 612