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1/*
2 * Copyright (c) 2000-2006 Silicon Graphics, Inc.
3 * All Rights Reserved.
4 *
5 * This program is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU General Public License as
7 * published by the Free Software Foundation.
8 *
9 * This program is distributed in the hope that it would be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write the Free Software Foundation,
16 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
17 */
18#include "xfs.h"
19#include "xfs_fs.h"
20#include "xfs_shared.h"
21#include "xfs_format.h"
22#include "xfs_log_format.h"
23#include "xfs_trans_resv.h"
24#include "xfs_bit.h"
25#include "xfs_sb.h"
26#include "xfs_mount.h"
27#include "xfs_defer.h"
28#include "xfs_da_format.h"
29#include "xfs_da_btree.h"
30#include "xfs_inode.h"
31#include "xfs_trans.h"
32#include "xfs_log.h"
33#include "xfs_log_priv.h"
34#include "xfs_log_recover.h"
35#include "xfs_inode_item.h"
36#include "xfs_extfree_item.h"
37#include "xfs_trans_priv.h"
38#include "xfs_alloc.h"
39#include "xfs_ialloc.h"
40#include "xfs_quota.h"
41#include "xfs_cksum.h"
42#include "xfs_trace.h"
43#include "xfs_icache.h"
44#include "xfs_bmap_btree.h"
45#include "xfs_error.h"
46#include "xfs_dir2.h"
47#include "xfs_rmap_item.h"
48#include "xfs_buf_item.h"
49#include "xfs_refcount_item.h"
50#include "xfs_bmap_item.h"
51
52#define BLK_AVG(blk1, blk2) ((blk1+blk2) >> 1)
53
54STATIC int
55xlog_find_zeroed(
56 struct xlog *,
57 xfs_daddr_t *);
58STATIC int
59xlog_clear_stale_blocks(
60 struct xlog *,
61 xfs_lsn_t);
62#if defined(DEBUG)
63STATIC void
64xlog_recover_check_summary(
65 struct xlog *);
66#else
67#define xlog_recover_check_summary(log)
68#endif
69STATIC int
70xlog_do_recovery_pass(
71 struct xlog *, xfs_daddr_t, xfs_daddr_t, int, xfs_daddr_t *);
72
73/*
74 * This structure is used during recovery to record the buf log items which
75 * have been canceled and should not be replayed.
76 */
77struct xfs_buf_cancel {
78 xfs_daddr_t bc_blkno;
79 uint bc_len;
80 int bc_refcount;
81 struct list_head bc_list;
82};
83
84/*
85 * Sector aligned buffer routines for buffer create/read/write/access
86 */
87
88/*
89 * Verify the log-relative block number and length in basic blocks are valid for
90 * an operation involving the given XFS log buffer. Returns true if the fields
91 * are valid, false otherwise.
92 */
93static inline bool
94xlog_verify_bp(
95 struct xlog *log,
96 xfs_daddr_t blk_no,
97 int bbcount)
98{
99 if (blk_no < 0 || blk_no >= log->l_logBBsize)
100 return false;
101 if (bbcount <= 0 || (blk_no + bbcount) > log->l_logBBsize)
102 return false;
103 return true;
104}
105
106/*
107 * Allocate a buffer to hold log data. The buffer needs to be able
108 * to map to a range of nbblks basic blocks at any valid (basic
109 * block) offset within the log.
110 */
111STATIC xfs_buf_t *
112xlog_get_bp(
113 struct xlog *log,
114 int nbblks)
115{
116 struct xfs_buf *bp;
117
118 /*
119 * Pass log block 0 since we don't have an addr yet, buffer will be
120 * verified on read.
121 */
122 if (!xlog_verify_bp(log, 0, nbblks)) {
123 xfs_warn(log->l_mp, "Invalid block length (0x%x) for buffer",
124 nbblks);
125 XFS_ERROR_REPORT(__func__, XFS_ERRLEVEL_HIGH, log->l_mp);
126 return NULL;
127 }
128
129 /*
130 * We do log I/O in units of log sectors (a power-of-2
131 * multiple of the basic block size), so we round up the
132 * requested size to accommodate the basic blocks required
133 * for complete log sectors.
134 *
135 * In addition, the buffer may be used for a non-sector-
136 * aligned block offset, in which case an I/O of the
137 * requested size could extend beyond the end of the
138 * buffer. If the requested size is only 1 basic block it
139 * will never straddle a sector boundary, so this won't be
140 * an issue. Nor will this be a problem if the log I/O is
141 * done in basic blocks (sector size 1). But otherwise we
142 * extend the buffer by one extra log sector to ensure
143 * there's space to accommodate this possibility.
144 */
145 if (nbblks > 1 && log->l_sectBBsize > 1)
146 nbblks += log->l_sectBBsize;
147 nbblks = round_up(nbblks, log->l_sectBBsize);
148
149 bp = xfs_buf_get_uncached(log->l_mp->m_logdev_targp, nbblks, 0);
150 if (bp)
151 xfs_buf_unlock(bp);
152 return bp;
153}
154
155STATIC void
156xlog_put_bp(
157 xfs_buf_t *bp)
158{
159 xfs_buf_free(bp);
160}
161
162/*
163 * Return the address of the start of the given block number's data
164 * in a log buffer. The buffer covers a log sector-aligned region.
165 */
166STATIC char *
167xlog_align(
168 struct xlog *log,
169 xfs_daddr_t blk_no,
170 int nbblks,
171 struct xfs_buf *bp)
172{
173 xfs_daddr_t offset = blk_no & ((xfs_daddr_t)log->l_sectBBsize - 1);
174
175 ASSERT(offset + nbblks <= bp->b_length);
176 return bp->b_addr + BBTOB(offset);
177}
178
179
180/*
181 * nbblks should be uint, but oh well. Just want to catch that 32-bit length.
182 */
183STATIC int
184xlog_bread_noalign(
185 struct xlog *log,
186 xfs_daddr_t blk_no,
187 int nbblks,
188 struct xfs_buf *bp)
189{
190 int error;
191
192 if (!xlog_verify_bp(log, blk_no, nbblks)) {
193 xfs_warn(log->l_mp,
194 "Invalid log block/length (0x%llx, 0x%x) for buffer",
195 blk_no, nbblks);
196 XFS_ERROR_REPORT(__func__, XFS_ERRLEVEL_HIGH, log->l_mp);
197 return -EFSCORRUPTED;
198 }
199
200 blk_no = round_down(blk_no, log->l_sectBBsize);
201 nbblks = round_up(nbblks, log->l_sectBBsize);
202
203 ASSERT(nbblks > 0);
204 ASSERT(nbblks <= bp->b_length);
205
206 XFS_BUF_SET_ADDR(bp, log->l_logBBstart + blk_no);
207 bp->b_flags |= XBF_READ;
208 bp->b_io_length = nbblks;
209 bp->b_error = 0;
210
211 error = xfs_buf_submit_wait(bp);
212 if (error && !XFS_FORCED_SHUTDOWN(log->l_mp))
213 xfs_buf_ioerror_alert(bp, __func__);
214 return error;
215}
216
217STATIC int
218xlog_bread(
219 struct xlog *log,
220 xfs_daddr_t blk_no,
221 int nbblks,
222 struct xfs_buf *bp,
223 char **offset)
224{
225 int error;
226
227 error = xlog_bread_noalign(log, blk_no, nbblks, bp);
228 if (error)
229 return error;
230
231 *offset = xlog_align(log, blk_no, nbblks, bp);
232 return 0;
233}
234
235/*
236 * Read at an offset into the buffer. Returns with the buffer in it's original
237 * state regardless of the result of the read.
238 */
239STATIC int
240xlog_bread_offset(
241 struct xlog *log,
242 xfs_daddr_t blk_no, /* block to read from */
243 int nbblks, /* blocks to read */
244 struct xfs_buf *bp,
245 char *offset)
246{
247 char *orig_offset = bp->b_addr;
248 int orig_len = BBTOB(bp->b_length);
249 int error, error2;
250
251 error = xfs_buf_associate_memory(bp, offset, BBTOB(nbblks));
252 if (error)
253 return error;
254
255 error = xlog_bread_noalign(log, blk_no, nbblks, bp);
256
257 /* must reset buffer pointer even on error */
258 error2 = xfs_buf_associate_memory(bp, orig_offset, orig_len);
259 if (error)
260 return error;
261 return error2;
262}
263
264/*
265 * Write out the buffer at the given block for the given number of blocks.
266 * The buffer is kept locked across the write and is returned locked.
267 * This can only be used for synchronous log writes.
268 */
269STATIC int
270xlog_bwrite(
271 struct xlog *log,
272 xfs_daddr_t blk_no,
273 int nbblks,
274 struct xfs_buf *bp)
275{
276 int error;
277
278 if (!xlog_verify_bp(log, blk_no, nbblks)) {
279 xfs_warn(log->l_mp,
280 "Invalid log block/length (0x%llx, 0x%x) for buffer",
281 blk_no, nbblks);
282 XFS_ERROR_REPORT(__func__, XFS_ERRLEVEL_HIGH, log->l_mp);
283 return -EFSCORRUPTED;
284 }
285
286 blk_no = round_down(blk_no, log->l_sectBBsize);
287 nbblks = round_up(nbblks, log->l_sectBBsize);
288
289 ASSERT(nbblks > 0);
290 ASSERT(nbblks <= bp->b_length);
291
292 XFS_BUF_SET_ADDR(bp, log->l_logBBstart + blk_no);
293 xfs_buf_hold(bp);
294 xfs_buf_lock(bp);
295 bp->b_io_length = nbblks;
296 bp->b_error = 0;
297
298 error = xfs_bwrite(bp);
299 if (error)
300 xfs_buf_ioerror_alert(bp, __func__);
301 xfs_buf_relse(bp);
302 return error;
303}
304
305#ifdef DEBUG
306/*
307 * dump debug superblock and log record information
308 */
309STATIC void
310xlog_header_check_dump(
311 xfs_mount_t *mp,
312 xlog_rec_header_t *head)
313{
314 xfs_debug(mp, "%s: SB : uuid = %pU, fmt = %d",
315 __func__, &mp->m_sb.sb_uuid, XLOG_FMT);
316 xfs_debug(mp, " log : uuid = %pU, fmt = %d",
317 &head->h_fs_uuid, be32_to_cpu(head->h_fmt));
318}
319#else
320#define xlog_header_check_dump(mp, head)
321#endif
322
323/*
324 * check log record header for recovery
325 */
326STATIC int
327xlog_header_check_recover(
328 xfs_mount_t *mp,
329 xlog_rec_header_t *head)
330{
331 ASSERT(head->h_magicno == cpu_to_be32(XLOG_HEADER_MAGIC_NUM));
332
333 /*
334 * IRIX doesn't write the h_fmt field and leaves it zeroed
335 * (XLOG_FMT_UNKNOWN). This stops us from trying to recover
336 * a dirty log created in IRIX.
337 */
338 if (unlikely(head->h_fmt != cpu_to_be32(XLOG_FMT))) {
339 xfs_warn(mp,
340 "dirty log written in incompatible format - can't recover");
341 xlog_header_check_dump(mp, head);
342 XFS_ERROR_REPORT("xlog_header_check_recover(1)",
343 XFS_ERRLEVEL_HIGH, mp);
344 return -EFSCORRUPTED;
345 } else if (unlikely(!uuid_equal(&mp->m_sb.sb_uuid, &head->h_fs_uuid))) {
346 xfs_warn(mp,
347 "dirty log entry has mismatched uuid - can't recover");
348 xlog_header_check_dump(mp, head);
349 XFS_ERROR_REPORT("xlog_header_check_recover(2)",
350 XFS_ERRLEVEL_HIGH, mp);
351 return -EFSCORRUPTED;
352 }
353 return 0;
354}
355
356/*
357 * read the head block of the log and check the header
358 */
359STATIC int
360xlog_header_check_mount(
361 xfs_mount_t *mp,
362 xlog_rec_header_t *head)
363{
364 ASSERT(head->h_magicno == cpu_to_be32(XLOG_HEADER_MAGIC_NUM));
365
366 if (uuid_is_null(&head->h_fs_uuid)) {
367 /*
368 * IRIX doesn't write the h_fs_uuid or h_fmt fields. If
369 * h_fs_uuid is null, we assume this log was last mounted
370 * by IRIX and continue.
371 */
372 xfs_warn(mp, "null uuid in log - IRIX style log");
373 } else if (unlikely(!uuid_equal(&mp->m_sb.sb_uuid, &head->h_fs_uuid))) {
374 xfs_warn(mp, "log has mismatched uuid - can't recover");
375 xlog_header_check_dump(mp, head);
376 XFS_ERROR_REPORT("xlog_header_check_mount",
377 XFS_ERRLEVEL_HIGH, mp);
378 return -EFSCORRUPTED;
379 }
380 return 0;
381}
382
383STATIC void
384xlog_recover_iodone(
385 struct xfs_buf *bp)
386{
387 if (bp->b_error) {
388 /*
389 * We're not going to bother about retrying
390 * this during recovery. One strike!
391 */
392 if (!XFS_FORCED_SHUTDOWN(bp->b_target->bt_mount)) {
393 xfs_buf_ioerror_alert(bp, __func__);
394 xfs_force_shutdown(bp->b_target->bt_mount,
395 SHUTDOWN_META_IO_ERROR);
396 }
397 }
398
399 /*
400 * On v5 supers, a bli could be attached to update the metadata LSN.
401 * Clean it up.
402 */
403 if (bp->b_log_item)
404 xfs_buf_item_relse(bp);
405 ASSERT(bp->b_log_item == NULL);
406
407 bp->b_iodone = NULL;
408 xfs_buf_ioend(bp);
409}
410
411/*
412 * This routine finds (to an approximation) the first block in the physical
413 * log which contains the given cycle. It uses a binary search algorithm.
414 * Note that the algorithm can not be perfect because the disk will not
415 * necessarily be perfect.
416 */
417STATIC int
418xlog_find_cycle_start(
419 struct xlog *log,
420 struct xfs_buf *bp,
421 xfs_daddr_t first_blk,
422 xfs_daddr_t *last_blk,
423 uint cycle)
424{
425 char *offset;
426 xfs_daddr_t mid_blk;
427 xfs_daddr_t end_blk;
428 uint mid_cycle;
429 int error;
430
431 end_blk = *last_blk;
432 mid_blk = BLK_AVG(first_blk, end_blk);
433 while (mid_blk != first_blk && mid_blk != end_blk) {
434 error = xlog_bread(log, mid_blk, 1, bp, &offset);
435 if (error)
436 return error;
437 mid_cycle = xlog_get_cycle(offset);
438 if (mid_cycle == cycle)
439 end_blk = mid_blk; /* last_half_cycle == mid_cycle */
440 else
441 first_blk = mid_blk; /* first_half_cycle == mid_cycle */
442 mid_blk = BLK_AVG(first_blk, end_blk);
443 }
444 ASSERT((mid_blk == first_blk && mid_blk+1 == end_blk) ||
445 (mid_blk == end_blk && mid_blk-1 == first_blk));
446
447 *last_blk = end_blk;
448
449 return 0;
450}
451
452/*
453 * Check that a range of blocks does not contain stop_on_cycle_no.
454 * Fill in *new_blk with the block offset where such a block is
455 * found, or with -1 (an invalid block number) if there is no such
456 * block in the range. The scan needs to occur from front to back
457 * and the pointer into the region must be updated since a later
458 * routine will need to perform another test.
459 */
460STATIC int
461xlog_find_verify_cycle(
462 struct xlog *log,
463 xfs_daddr_t start_blk,
464 int nbblks,
465 uint stop_on_cycle_no,
466 xfs_daddr_t *new_blk)
467{
468 xfs_daddr_t i, j;
469 uint cycle;
470 xfs_buf_t *bp;
471 xfs_daddr_t bufblks;
472 char *buf = NULL;
473 int error = 0;
474
475 /*
476 * Greedily allocate a buffer big enough to handle the full
477 * range of basic blocks we'll be examining. If that fails,
478 * try a smaller size. We need to be able to read at least
479 * a log sector, or we're out of luck.
480 */
481 bufblks = 1 << ffs(nbblks);
482 while (bufblks > log->l_logBBsize)
483 bufblks >>= 1;
484 while (!(bp = xlog_get_bp(log, bufblks))) {
485 bufblks >>= 1;
486 if (bufblks < log->l_sectBBsize)
487 return -ENOMEM;
488 }
489
490 for (i = start_blk; i < start_blk + nbblks; i += bufblks) {
491 int bcount;
492
493 bcount = min(bufblks, (start_blk + nbblks - i));
494
495 error = xlog_bread(log, i, bcount, bp, &buf);
496 if (error)
497 goto out;
498
499 for (j = 0; j < bcount; j++) {
500 cycle = xlog_get_cycle(buf);
501 if (cycle == stop_on_cycle_no) {
502 *new_blk = i+j;
503 goto out;
504 }
505
506 buf += BBSIZE;
507 }
508 }
509
510 *new_blk = -1;
511
512out:
513 xlog_put_bp(bp);
514 return error;
515}
516
517/*
518 * Potentially backup over partial log record write.
519 *
520 * In the typical case, last_blk is the number of the block directly after
521 * a good log record. Therefore, we subtract one to get the block number
522 * of the last block in the given buffer. extra_bblks contains the number
523 * of blocks we would have read on a previous read. This happens when the
524 * last log record is split over the end of the physical log.
525 *
526 * extra_bblks is the number of blocks potentially verified on a previous
527 * call to this routine.
528 */
529STATIC int
530xlog_find_verify_log_record(
531 struct xlog *log,
532 xfs_daddr_t start_blk,
533 xfs_daddr_t *last_blk,
534 int extra_bblks)
535{
536 xfs_daddr_t i;
537 xfs_buf_t *bp;
538 char *offset = NULL;
539 xlog_rec_header_t *head = NULL;
540 int error = 0;
541 int smallmem = 0;
542 int num_blks = *last_blk - start_blk;
543 int xhdrs;
544
545 ASSERT(start_blk != 0 || *last_blk != start_blk);
546
547 if (!(bp = xlog_get_bp(log, num_blks))) {
548 if (!(bp = xlog_get_bp(log, 1)))
549 return -ENOMEM;
550 smallmem = 1;
551 } else {
552 error = xlog_bread(log, start_blk, num_blks, bp, &offset);
553 if (error)
554 goto out;
555 offset += ((num_blks - 1) << BBSHIFT);
556 }
557
558 for (i = (*last_blk) - 1; i >= 0; i--) {
559 if (i < start_blk) {
560 /* valid log record not found */
561 xfs_warn(log->l_mp,
562 "Log inconsistent (didn't find previous header)");
563 ASSERT(0);
564 error = -EIO;
565 goto out;
566 }
567
568 if (smallmem) {
569 error = xlog_bread(log, i, 1, bp, &offset);
570 if (error)
571 goto out;
572 }
573
574 head = (xlog_rec_header_t *)offset;
575
576 if (head->h_magicno == cpu_to_be32(XLOG_HEADER_MAGIC_NUM))
577 break;
578
579 if (!smallmem)
580 offset -= BBSIZE;
581 }
582
583 /*
584 * We hit the beginning of the physical log & still no header. Return
585 * to caller. If caller can handle a return of -1, then this routine
586 * will be called again for the end of the physical log.
587 */
588 if (i == -1) {
589 error = 1;
590 goto out;
591 }
592
593 /*
594 * We have the final block of the good log (the first block
595 * of the log record _before_ the head. So we check the uuid.
596 */
597 if ((error = xlog_header_check_mount(log->l_mp, head)))
598 goto out;
599
600 /*
601 * We may have found a log record header before we expected one.
602 * last_blk will be the 1st block # with a given cycle #. We may end
603 * up reading an entire log record. In this case, we don't want to
604 * reset last_blk. Only when last_blk points in the middle of a log
605 * record do we update last_blk.
606 */
607 if (xfs_sb_version_haslogv2(&log->l_mp->m_sb)) {
608 uint h_size = be32_to_cpu(head->h_size);
609
610 xhdrs = h_size / XLOG_HEADER_CYCLE_SIZE;
611 if (h_size % XLOG_HEADER_CYCLE_SIZE)
612 xhdrs++;
613 } else {
614 xhdrs = 1;
615 }
616
617 if (*last_blk - i + extra_bblks !=
618 BTOBB(be32_to_cpu(head->h_len)) + xhdrs)
619 *last_blk = i;
620
621out:
622 xlog_put_bp(bp);
623 return error;
624}
625
626/*
627 * Head is defined to be the point of the log where the next log write
628 * could go. This means that incomplete LR writes at the end are
629 * eliminated when calculating the head. We aren't guaranteed that previous
630 * LR have complete transactions. We only know that a cycle number of
631 * current cycle number -1 won't be present in the log if we start writing
632 * from our current block number.
633 *
634 * last_blk contains the block number of the first block with a given
635 * cycle number.
636 *
637 * Return: zero if normal, non-zero if error.
638 */
639STATIC int
640xlog_find_head(
641 struct xlog *log,
642 xfs_daddr_t *return_head_blk)
643{
644 xfs_buf_t *bp;
645 char *offset;
646 xfs_daddr_t new_blk, first_blk, start_blk, last_blk, head_blk;
647 int num_scan_bblks;
648 uint first_half_cycle, last_half_cycle;
649 uint stop_on_cycle;
650 int error, log_bbnum = log->l_logBBsize;
651
652 /* Is the end of the log device zeroed? */
653 error = xlog_find_zeroed(log, &first_blk);
654 if (error < 0) {
655 xfs_warn(log->l_mp, "empty log check failed");
656 return error;
657 }
658 if (error == 1) {
659 *return_head_blk = first_blk;
660
661 /* Is the whole lot zeroed? */
662 if (!first_blk) {
663 /* Linux XFS shouldn't generate totally zeroed logs -
664 * mkfs etc write a dummy unmount record to a fresh
665 * log so we can store the uuid in there
666 */
667 xfs_warn(log->l_mp, "totally zeroed log");
668 }
669
670 return 0;
671 }
672
673 first_blk = 0; /* get cycle # of 1st block */
674 bp = xlog_get_bp(log, 1);
675 if (!bp)
676 return -ENOMEM;
677
678 error = xlog_bread(log, 0, 1, bp, &offset);
679 if (error)
680 goto bp_err;
681
682 first_half_cycle = xlog_get_cycle(offset);
683
684 last_blk = head_blk = log_bbnum - 1; /* get cycle # of last block */
685 error = xlog_bread(log, last_blk, 1, bp, &offset);
686 if (error)
687 goto bp_err;
688
689 last_half_cycle = xlog_get_cycle(offset);
690 ASSERT(last_half_cycle != 0);
691
692 /*
693 * If the 1st half cycle number is equal to the last half cycle number,
694 * then the entire log is stamped with the same cycle number. In this
695 * case, head_blk can't be set to zero (which makes sense). The below
696 * math doesn't work out properly with head_blk equal to zero. Instead,
697 * we set it to log_bbnum which is an invalid block number, but this
698 * value makes the math correct. If head_blk doesn't changed through
699 * all the tests below, *head_blk is set to zero at the very end rather
700 * than log_bbnum. In a sense, log_bbnum and zero are the same block
701 * in a circular file.
702 */
703 if (first_half_cycle == last_half_cycle) {
704 /*
705 * In this case we believe that the entire log should have
706 * cycle number last_half_cycle. We need to scan backwards
707 * from the end verifying that there are no holes still
708 * containing last_half_cycle - 1. If we find such a hole,
709 * then the start of that hole will be the new head. The
710 * simple case looks like
711 * x | x ... | x - 1 | x
712 * Another case that fits this picture would be
713 * x | x + 1 | x ... | x
714 * In this case the head really is somewhere at the end of the
715 * log, as one of the latest writes at the beginning was
716 * incomplete.
717 * One more case is
718 * x | x + 1 | x ... | x - 1 | x
719 * This is really the combination of the above two cases, and
720 * the head has to end up at the start of the x-1 hole at the
721 * end of the log.
722 *
723 * In the 256k log case, we will read from the beginning to the
724 * end of the log and search for cycle numbers equal to x-1.
725 * We don't worry about the x+1 blocks that we encounter,
726 * because we know that they cannot be the head since the log
727 * started with x.
728 */
729 head_blk = log_bbnum;
730 stop_on_cycle = last_half_cycle - 1;
731 } else {
732 /*
733 * In this case we want to find the first block with cycle
734 * number matching last_half_cycle. We expect the log to be
735 * some variation on
736 * x + 1 ... | x ... | x
737 * The first block with cycle number x (last_half_cycle) will
738 * be where the new head belongs. First we do a binary search
739 * for the first occurrence of last_half_cycle. The binary
740 * search may not be totally accurate, so then we scan back
741 * from there looking for occurrences of last_half_cycle before
742 * us. If that backwards scan wraps around the beginning of
743 * the log, then we look for occurrences of last_half_cycle - 1
744 * at the end of the log. The cases we're looking for look
745 * like
746 * v binary search stopped here
747 * x + 1 ... | x | x + 1 | x ... | x
748 * ^ but we want to locate this spot
749 * or
750 * <---------> less than scan distance
751 * x + 1 ... | x ... | x - 1 | x
752 * ^ we want to locate this spot
753 */
754 stop_on_cycle = last_half_cycle;
755 if ((error = xlog_find_cycle_start(log, bp, first_blk,
756 &head_blk, last_half_cycle)))
757 goto bp_err;
758 }
759
760 /*
761 * Now validate the answer. Scan back some number of maximum possible
762 * blocks and make sure each one has the expected cycle number. The
763 * maximum is determined by the total possible amount of buffering
764 * in the in-core log. The following number can be made tighter if
765 * we actually look at the block size of the filesystem.
766 */
767 num_scan_bblks = min_t(int, log_bbnum, XLOG_TOTAL_REC_SHIFT(log));
768 if (head_blk >= num_scan_bblks) {
769 /*
770 * We are guaranteed that the entire check can be performed
771 * in one buffer.
772 */
773 start_blk = head_blk - num_scan_bblks;
774 if ((error = xlog_find_verify_cycle(log,
775 start_blk, num_scan_bblks,
776 stop_on_cycle, &new_blk)))
777 goto bp_err;
778 if (new_blk != -1)
779 head_blk = new_blk;
780 } else { /* need to read 2 parts of log */
781 /*
782 * We are going to scan backwards in the log in two parts.
783 * First we scan the physical end of the log. In this part
784 * of the log, we are looking for blocks with cycle number
785 * last_half_cycle - 1.
786 * If we find one, then we know that the log starts there, as
787 * we've found a hole that didn't get written in going around
788 * the end of the physical log. The simple case for this is
789 * x + 1 ... | x ... | x - 1 | x
790 * <---------> less than scan distance
791 * If all of the blocks at the end of the log have cycle number
792 * last_half_cycle, then we check the blocks at the start of
793 * the log looking for occurrences of last_half_cycle. If we
794 * find one, then our current estimate for the location of the
795 * first occurrence of last_half_cycle is wrong and we move
796 * back to the hole we've found. This case looks like
797 * x + 1 ... | x | x + 1 | x ...
798 * ^ binary search stopped here
799 * Another case we need to handle that only occurs in 256k
800 * logs is
801 * x + 1 ... | x ... | x+1 | x ...
802 * ^ binary search stops here
803 * In a 256k log, the scan at the end of the log will see the
804 * x + 1 blocks. We need to skip past those since that is
805 * certainly not the head of the log. By searching for
806 * last_half_cycle-1 we accomplish that.
807 */
808 ASSERT(head_blk <= INT_MAX &&
809 (xfs_daddr_t) num_scan_bblks >= head_blk);
810 start_blk = log_bbnum - (num_scan_bblks - head_blk);
811 if ((error = xlog_find_verify_cycle(log, start_blk,
812 num_scan_bblks - (int)head_blk,
813 (stop_on_cycle - 1), &new_blk)))
814 goto bp_err;
815 if (new_blk != -1) {
816 head_blk = new_blk;
817 goto validate_head;
818 }
819
820 /*
821 * Scan beginning of log now. The last part of the physical
822 * log is good. This scan needs to verify that it doesn't find
823 * the last_half_cycle.
824 */
825 start_blk = 0;
826 ASSERT(head_blk <= INT_MAX);
827 if ((error = xlog_find_verify_cycle(log,
828 start_blk, (int)head_blk,
829 stop_on_cycle, &new_blk)))
830 goto bp_err;
831 if (new_blk != -1)
832 head_blk = new_blk;
833 }
834
835validate_head:
836 /*
837 * Now we need to make sure head_blk is not pointing to a block in
838 * the middle of a log record.
839 */
840 num_scan_bblks = XLOG_REC_SHIFT(log);
841 if (head_blk >= num_scan_bblks) {
842 start_blk = head_blk - num_scan_bblks; /* don't read head_blk */
843
844 /* start ptr at last block ptr before head_blk */
845 error = xlog_find_verify_log_record(log, start_blk, &head_blk, 0);
846 if (error == 1)
847 error = -EIO;
848 if (error)
849 goto bp_err;
850 } else {
851 start_blk = 0;
852 ASSERT(head_blk <= INT_MAX);
853 error = xlog_find_verify_log_record(log, start_blk, &head_blk, 0);
854 if (error < 0)
855 goto bp_err;
856 if (error == 1) {
857 /* We hit the beginning of the log during our search */
858 start_blk = log_bbnum - (num_scan_bblks - head_blk);
859 new_blk = log_bbnum;
860 ASSERT(start_blk <= INT_MAX &&
861 (xfs_daddr_t) log_bbnum-start_blk >= 0);
862 ASSERT(head_blk <= INT_MAX);
863 error = xlog_find_verify_log_record(log, start_blk,
864 &new_blk, (int)head_blk);
865 if (error == 1)
866 error = -EIO;
867 if (error)
868 goto bp_err;
869 if (new_blk != log_bbnum)
870 head_blk = new_blk;
871 } else if (error)
872 goto bp_err;
873 }
874
875 xlog_put_bp(bp);
876 if (head_blk == log_bbnum)
877 *return_head_blk = 0;
878 else
879 *return_head_blk = head_blk;
880 /*
881 * When returning here, we have a good block number. Bad block
882 * means that during a previous crash, we didn't have a clean break
883 * from cycle number N to cycle number N-1. In this case, we need
884 * to find the first block with cycle number N-1.
885 */
886 return 0;
887
888 bp_err:
889 xlog_put_bp(bp);
890
891 if (error)
892 xfs_warn(log->l_mp, "failed to find log head");
893 return error;
894}
895
896/*
897 * Seek backwards in the log for log record headers.
898 *
899 * Given a starting log block, walk backwards until we find the provided number
900 * of records or hit the provided tail block. The return value is the number of
901 * records encountered or a negative error code. The log block and buffer
902 * pointer of the last record seen are returned in rblk and rhead respectively.
903 */
904STATIC int
905xlog_rseek_logrec_hdr(
906 struct xlog *log,
907 xfs_daddr_t head_blk,
908 xfs_daddr_t tail_blk,
909 int count,
910 struct xfs_buf *bp,
911 xfs_daddr_t *rblk,
912 struct xlog_rec_header **rhead,
913 bool *wrapped)
914{
915 int i;
916 int error;
917 int found = 0;
918 char *offset = NULL;
919 xfs_daddr_t end_blk;
920
921 *wrapped = false;
922
923 /*
924 * Walk backwards from the head block until we hit the tail or the first
925 * block in the log.
926 */
927 end_blk = head_blk > tail_blk ? tail_blk : 0;
928 for (i = (int) head_blk - 1; i >= end_blk; i--) {
929 error = xlog_bread(log, i, 1, bp, &offset);
930 if (error)
931 goto out_error;
932
933 if (*(__be32 *) offset == cpu_to_be32(XLOG_HEADER_MAGIC_NUM)) {
934 *rblk = i;
935 *rhead = (struct xlog_rec_header *) offset;
936 if (++found == count)
937 break;
938 }
939 }
940
941 /*
942 * If we haven't hit the tail block or the log record header count,
943 * start looking again from the end of the physical log. Note that
944 * callers can pass head == tail if the tail is not yet known.
945 */
946 if (tail_blk >= head_blk && found != count) {
947 for (i = log->l_logBBsize - 1; i >= (int) tail_blk; i--) {
948 error = xlog_bread(log, i, 1, bp, &offset);
949 if (error)
950 goto out_error;
951
952 if (*(__be32 *)offset ==
953 cpu_to_be32(XLOG_HEADER_MAGIC_NUM)) {
954 *wrapped = true;
955 *rblk = i;
956 *rhead = (struct xlog_rec_header *) offset;
957 if (++found == count)
958 break;
959 }
960 }
961 }
962
963 return found;
964
965out_error:
966 return error;
967}
968
969/*
970 * Seek forward in the log for log record headers.
971 *
972 * Given head and tail blocks, walk forward from the tail block until we find
973 * the provided number of records or hit the head block. The return value is the
974 * number of records encountered or a negative error code. The log block and
975 * buffer pointer of the last record seen are returned in rblk and rhead
976 * respectively.
977 */
978STATIC int
979xlog_seek_logrec_hdr(
980 struct xlog *log,
981 xfs_daddr_t head_blk,
982 xfs_daddr_t tail_blk,
983 int count,
984 struct xfs_buf *bp,
985 xfs_daddr_t *rblk,
986 struct xlog_rec_header **rhead,
987 bool *wrapped)
988{
989 int i;
990 int error;
991 int found = 0;
992 char *offset = NULL;
993 xfs_daddr_t end_blk;
994
995 *wrapped = false;
996
997 /*
998 * Walk forward from the tail block until we hit the head or the last
999 * block in the log.
1000 */
1001 end_blk = head_blk > tail_blk ? head_blk : log->l_logBBsize - 1;
1002 for (i = (int) tail_blk; i <= end_blk; i++) {
1003 error = xlog_bread(log, i, 1, bp, &offset);
1004 if (error)
1005 goto out_error;
1006
1007 if (*(__be32 *) offset == cpu_to_be32(XLOG_HEADER_MAGIC_NUM)) {
1008 *rblk = i;
1009 *rhead = (struct xlog_rec_header *) offset;
1010 if (++found == count)
1011 break;
1012 }
1013 }
1014
1015 /*
1016 * If we haven't hit the head block or the log record header count,
1017 * start looking again from the start of the physical log.
1018 */
1019 if (tail_blk > head_blk && found != count) {
1020 for (i = 0; i < (int) head_blk; i++) {
1021 error = xlog_bread(log, i, 1, bp, &offset);
1022 if (error)
1023 goto out_error;
1024
1025 if (*(__be32 *)offset ==
1026 cpu_to_be32(XLOG_HEADER_MAGIC_NUM)) {
1027 *wrapped = true;
1028 *rblk = i;
1029 *rhead = (struct xlog_rec_header *) offset;
1030 if (++found == count)
1031 break;
1032 }
1033 }
1034 }
1035
1036 return found;
1037
1038out_error:
1039 return error;
1040}
1041
1042/*
1043 * Calculate distance from head to tail (i.e., unused space in the log).
1044 */
1045static inline int
1046xlog_tail_distance(
1047 struct xlog *log,
1048 xfs_daddr_t head_blk,
1049 xfs_daddr_t tail_blk)
1050{
1051 if (head_blk < tail_blk)
1052 return tail_blk - head_blk;
1053
1054 return tail_blk + (log->l_logBBsize - head_blk);
1055}
1056
1057/*
1058 * Verify the log tail. This is particularly important when torn or incomplete
1059 * writes have been detected near the front of the log and the head has been
1060 * walked back accordingly.
1061 *
1062 * We also have to handle the case where the tail was pinned and the head
1063 * blocked behind the tail right before a crash. If the tail had been pushed
1064 * immediately prior to the crash and the subsequent checkpoint was only
1065 * partially written, it's possible it overwrote the last referenced tail in the
1066 * log with garbage. This is not a coherency problem because the tail must have
1067 * been pushed before it can be overwritten, but appears as log corruption to
1068 * recovery because we have no way to know the tail was updated if the
1069 * subsequent checkpoint didn't write successfully.
1070 *
1071 * Therefore, CRC check the log from tail to head. If a failure occurs and the
1072 * offending record is within max iclog bufs from the head, walk the tail
1073 * forward and retry until a valid tail is found or corruption is detected out
1074 * of the range of a possible overwrite.
1075 */
1076STATIC int
1077xlog_verify_tail(
1078 struct xlog *log,
1079 xfs_daddr_t head_blk,
1080 xfs_daddr_t *tail_blk,
1081 int hsize)
1082{
1083 struct xlog_rec_header *thead;
1084 struct xfs_buf *bp;
1085 xfs_daddr_t first_bad;
1086 int error = 0;
1087 bool wrapped;
1088 xfs_daddr_t tmp_tail;
1089 xfs_daddr_t orig_tail = *tail_blk;
1090
1091 bp = xlog_get_bp(log, 1);
1092 if (!bp)
1093 return -ENOMEM;
1094
1095 /*
1096 * Make sure the tail points to a record (returns positive count on
1097 * success).
1098 */
1099 error = xlog_seek_logrec_hdr(log, head_blk, *tail_blk, 1, bp,
1100 &tmp_tail, &thead, &wrapped);
1101 if (error < 0)
1102 goto out;
1103 if (*tail_blk != tmp_tail)
1104 *tail_blk = tmp_tail;
1105
1106 /*
1107 * Run a CRC check from the tail to the head. We can't just check
1108 * MAX_ICLOGS records past the tail because the tail may point to stale
1109 * blocks cleared during the search for the head/tail. These blocks are
1110 * overwritten with zero-length records and thus record count is not a
1111 * reliable indicator of the iclog state before a crash.
1112 */
1113 first_bad = 0;
1114 error = xlog_do_recovery_pass(log, head_blk, *tail_blk,
1115 XLOG_RECOVER_CRCPASS, &first_bad);
1116 while ((error == -EFSBADCRC || error == -EFSCORRUPTED) && first_bad) {
1117 int tail_distance;
1118
1119 /*
1120 * Is corruption within range of the head? If so, retry from
1121 * the next record. Otherwise return an error.
1122 */
1123 tail_distance = xlog_tail_distance(log, head_blk, first_bad);
1124 if (tail_distance > BTOBB(XLOG_MAX_ICLOGS * hsize))
1125 break;
1126
1127 /* skip to the next record; returns positive count on success */
1128 error = xlog_seek_logrec_hdr(log, head_blk, first_bad, 2, bp,
1129 &tmp_tail, &thead, &wrapped);
1130 if (error < 0)
1131 goto out;
1132
1133 *tail_blk = tmp_tail;
1134 first_bad = 0;
1135 error = xlog_do_recovery_pass(log, head_blk, *tail_blk,
1136 XLOG_RECOVER_CRCPASS, &first_bad);
1137 }
1138
1139 if (!error && *tail_blk != orig_tail)
1140 xfs_warn(log->l_mp,
1141 "Tail block (0x%llx) overwrite detected. Updated to 0x%llx",
1142 orig_tail, *tail_blk);
1143out:
1144 xlog_put_bp(bp);
1145 return error;
1146}
1147
1148/*
1149 * Detect and trim torn writes from the head of the log.
1150 *
1151 * Storage without sector atomicity guarantees can result in torn writes in the
1152 * log in the event of a crash. Our only means to detect this scenario is via
1153 * CRC verification. While we can't always be certain that CRC verification
1154 * failure is due to a torn write vs. an unrelated corruption, we do know that
1155 * only a certain number (XLOG_MAX_ICLOGS) of log records can be written out at
1156 * one time. Therefore, CRC verify up to XLOG_MAX_ICLOGS records at the head of
1157 * the log and treat failures in this range as torn writes as a matter of
1158 * policy. In the event of CRC failure, the head is walked back to the last good
1159 * record in the log and the tail is updated from that record and verified.
1160 */
1161STATIC int
1162xlog_verify_head(
1163 struct xlog *log,
1164 xfs_daddr_t *head_blk, /* in/out: unverified head */
1165 xfs_daddr_t *tail_blk, /* out: tail block */
1166 struct xfs_buf *bp,
1167 xfs_daddr_t *rhead_blk, /* start blk of last record */
1168 struct xlog_rec_header **rhead, /* ptr to last record */
1169 bool *wrapped) /* last rec. wraps phys. log */
1170{
1171 struct xlog_rec_header *tmp_rhead;
1172 struct xfs_buf *tmp_bp;
1173 xfs_daddr_t first_bad;
1174 xfs_daddr_t tmp_rhead_blk;
1175 int found;
1176 int error;
1177 bool tmp_wrapped;
1178
1179 /*
1180 * Check the head of the log for torn writes. Search backwards from the
1181 * head until we hit the tail or the maximum number of log record I/Os
1182 * that could have been in flight at one time. Use a temporary buffer so
1183 * we don't trash the rhead/bp pointers from the caller.
1184 */
1185 tmp_bp = xlog_get_bp(log, 1);
1186 if (!tmp_bp)
1187 return -ENOMEM;
1188 error = xlog_rseek_logrec_hdr(log, *head_blk, *tail_blk,
1189 XLOG_MAX_ICLOGS, tmp_bp, &tmp_rhead_blk,
1190 &tmp_rhead, &tmp_wrapped);
1191 xlog_put_bp(tmp_bp);
1192 if (error < 0)
1193 return error;
1194
1195 /*
1196 * Now run a CRC verification pass over the records starting at the
1197 * block found above to the current head. If a CRC failure occurs, the
1198 * log block of the first bad record is saved in first_bad.
1199 */
1200 error = xlog_do_recovery_pass(log, *head_blk, tmp_rhead_blk,
1201 XLOG_RECOVER_CRCPASS, &first_bad);
1202 if ((error == -EFSBADCRC || error == -EFSCORRUPTED) && first_bad) {
1203 /*
1204 * We've hit a potential torn write. Reset the error and warn
1205 * about it.
1206 */
1207 error = 0;
1208 xfs_warn(log->l_mp,
1209"Torn write (CRC failure) detected at log block 0x%llx. Truncating head block from 0x%llx.",
1210 first_bad, *head_blk);
1211
1212 /*
1213 * Get the header block and buffer pointer for the last good
1214 * record before the bad record.
1215 *
1216 * Note that xlog_find_tail() clears the blocks at the new head
1217 * (i.e., the records with invalid CRC) if the cycle number
1218 * matches the the current cycle.
1219 */
1220 found = xlog_rseek_logrec_hdr(log, first_bad, *tail_blk, 1, bp,
1221 rhead_blk, rhead, wrapped);
1222 if (found < 0)
1223 return found;
1224 if (found == 0) /* XXX: right thing to do here? */
1225 return -EIO;
1226
1227 /*
1228 * Reset the head block to the starting block of the first bad
1229 * log record and set the tail block based on the last good
1230 * record.
1231 *
1232 * Bail out if the updated head/tail match as this indicates
1233 * possible corruption outside of the acceptable
1234 * (XLOG_MAX_ICLOGS) range. This is a job for xfs_repair...
1235 */
1236 *head_blk = first_bad;
1237 *tail_blk = BLOCK_LSN(be64_to_cpu((*rhead)->h_tail_lsn));
1238 if (*head_blk == *tail_blk) {
1239 ASSERT(0);
1240 return 0;
1241 }
1242 }
1243 if (error)
1244 return error;
1245
1246 return xlog_verify_tail(log, *head_blk, tail_blk,
1247 be32_to_cpu((*rhead)->h_size));
1248}
1249
1250/*
1251 * Check whether the head of the log points to an unmount record. In other
1252 * words, determine whether the log is clean. If so, update the in-core state
1253 * appropriately.
1254 */
1255static int
1256xlog_check_unmount_rec(
1257 struct xlog *log,
1258 xfs_daddr_t *head_blk,
1259 xfs_daddr_t *tail_blk,
1260 struct xlog_rec_header *rhead,
1261 xfs_daddr_t rhead_blk,
1262 struct xfs_buf *bp,
1263 bool *clean)
1264{
1265 struct xlog_op_header *op_head;
1266 xfs_daddr_t umount_data_blk;
1267 xfs_daddr_t after_umount_blk;
1268 int hblks;
1269 int error;
1270 char *offset;
1271
1272 *clean = false;
1273
1274 /*
1275 * Look for unmount record. If we find it, then we know there was a
1276 * clean unmount. Since 'i' could be the last block in the physical
1277 * log, we convert to a log block before comparing to the head_blk.
1278 *
1279 * Save the current tail lsn to use to pass to xlog_clear_stale_blocks()
1280 * below. We won't want to clear the unmount record if there is one, so
1281 * we pass the lsn of the unmount record rather than the block after it.
1282 */
1283 if (xfs_sb_version_haslogv2(&log->l_mp->m_sb)) {
1284 int h_size = be32_to_cpu(rhead->h_size);
1285 int h_version = be32_to_cpu(rhead->h_version);
1286
1287 if ((h_version & XLOG_VERSION_2) &&
1288 (h_size > XLOG_HEADER_CYCLE_SIZE)) {
1289 hblks = h_size / XLOG_HEADER_CYCLE_SIZE;
1290 if (h_size % XLOG_HEADER_CYCLE_SIZE)
1291 hblks++;
1292 } else {
1293 hblks = 1;
1294 }
1295 } else {
1296 hblks = 1;
1297 }
1298 after_umount_blk = rhead_blk + hblks + BTOBB(be32_to_cpu(rhead->h_len));
1299 after_umount_blk = do_mod(after_umount_blk, log->l_logBBsize);
1300 if (*head_blk == after_umount_blk &&
1301 be32_to_cpu(rhead->h_num_logops) == 1) {
1302 umount_data_blk = rhead_blk + hblks;
1303 umount_data_blk = do_mod(umount_data_blk, log->l_logBBsize);
1304 error = xlog_bread(log, umount_data_blk, 1, bp, &offset);
1305 if (error)
1306 return error;
1307
1308 op_head = (struct xlog_op_header *)offset;
1309 if (op_head->oh_flags & XLOG_UNMOUNT_TRANS) {
1310 /*
1311 * Set tail and last sync so that newly written log
1312 * records will point recovery to after the current
1313 * unmount record.
1314 */
1315 xlog_assign_atomic_lsn(&log->l_tail_lsn,
1316 log->l_curr_cycle, after_umount_blk);
1317 xlog_assign_atomic_lsn(&log->l_last_sync_lsn,
1318 log->l_curr_cycle, after_umount_blk);
1319 *tail_blk = after_umount_blk;
1320
1321 *clean = true;
1322 }
1323 }
1324
1325 return 0;
1326}
1327
1328static void
1329xlog_set_state(
1330 struct xlog *log,
1331 xfs_daddr_t head_blk,
1332 struct xlog_rec_header *rhead,
1333 xfs_daddr_t rhead_blk,
1334 bool bump_cycle)
1335{
1336 /*
1337 * Reset log values according to the state of the log when we
1338 * crashed. In the case where head_blk == 0, we bump curr_cycle
1339 * one because the next write starts a new cycle rather than
1340 * continuing the cycle of the last good log record. At this
1341 * point we have guaranteed that all partial log records have been
1342 * accounted for. Therefore, we know that the last good log record
1343 * written was complete and ended exactly on the end boundary
1344 * of the physical log.
1345 */
1346 log->l_prev_block = rhead_blk;
1347 log->l_curr_block = (int)head_blk;
1348 log->l_curr_cycle = be32_to_cpu(rhead->h_cycle);
1349 if (bump_cycle)
1350 log->l_curr_cycle++;
1351 atomic64_set(&log->l_tail_lsn, be64_to_cpu(rhead->h_tail_lsn));
1352 atomic64_set(&log->l_last_sync_lsn, be64_to_cpu(rhead->h_lsn));
1353 xlog_assign_grant_head(&log->l_reserve_head.grant, log->l_curr_cycle,
1354 BBTOB(log->l_curr_block));
1355 xlog_assign_grant_head(&log->l_write_head.grant, log->l_curr_cycle,
1356 BBTOB(log->l_curr_block));
1357}
1358
1359/*
1360 * Find the sync block number or the tail of the log.
1361 *
1362 * This will be the block number of the last record to have its
1363 * associated buffers synced to disk. Every log record header has
1364 * a sync lsn embedded in it. LSNs hold block numbers, so it is easy
1365 * to get a sync block number. The only concern is to figure out which
1366 * log record header to believe.
1367 *
1368 * The following algorithm uses the log record header with the largest
1369 * lsn. The entire log record does not need to be valid. We only care
1370 * that the header is valid.
1371 *
1372 * We could speed up search by using current head_blk buffer, but it is not
1373 * available.
1374 */
1375STATIC int
1376xlog_find_tail(
1377 struct xlog *log,
1378 xfs_daddr_t *head_blk,
1379 xfs_daddr_t *tail_blk)
1380{
1381 xlog_rec_header_t *rhead;
1382 char *offset = NULL;
1383 xfs_buf_t *bp;
1384 int error;
1385 xfs_daddr_t rhead_blk;
1386 xfs_lsn_t tail_lsn;
1387 bool wrapped = false;
1388 bool clean = false;
1389
1390 /*
1391 * Find previous log record
1392 */
1393 if ((error = xlog_find_head(log, head_blk)))
1394 return error;
1395 ASSERT(*head_blk < INT_MAX);
1396
1397 bp = xlog_get_bp(log, 1);
1398 if (!bp)
1399 return -ENOMEM;
1400 if (*head_blk == 0) { /* special case */
1401 error = xlog_bread(log, 0, 1, bp, &offset);
1402 if (error)
1403 goto done;
1404
1405 if (xlog_get_cycle(offset) == 0) {
1406 *tail_blk = 0;
1407 /* leave all other log inited values alone */
1408 goto done;
1409 }
1410 }
1411
1412 /*
1413 * Search backwards through the log looking for the log record header
1414 * block. This wraps all the way back around to the head so something is
1415 * seriously wrong if we can't find it.
1416 */
1417 error = xlog_rseek_logrec_hdr(log, *head_blk, *head_blk, 1, bp,
1418 &rhead_blk, &rhead, &wrapped);
1419 if (error < 0)
1420 return error;
1421 if (!error) {
1422 xfs_warn(log->l_mp, "%s: couldn't find sync record", __func__);
1423 return -EIO;
1424 }
1425 *tail_blk = BLOCK_LSN(be64_to_cpu(rhead->h_tail_lsn));
1426
1427 /*
1428 * Set the log state based on the current head record.
1429 */
1430 xlog_set_state(log, *head_blk, rhead, rhead_blk, wrapped);
1431 tail_lsn = atomic64_read(&log->l_tail_lsn);
1432
1433 /*
1434 * Look for an unmount record at the head of the log. This sets the log
1435 * state to determine whether recovery is necessary.
1436 */
1437 error = xlog_check_unmount_rec(log, head_blk, tail_blk, rhead,
1438 rhead_blk, bp, &clean);
1439 if (error)
1440 goto done;
1441
1442 /*
1443 * Verify the log head if the log is not clean (e.g., we have anything
1444 * but an unmount record at the head). This uses CRC verification to
1445 * detect and trim torn writes. If discovered, CRC failures are
1446 * considered torn writes and the log head is trimmed accordingly.
1447 *
1448 * Note that we can only run CRC verification when the log is dirty
1449 * because there's no guarantee that the log data behind an unmount
1450 * record is compatible with the current architecture.
1451 */
1452 if (!clean) {
1453 xfs_daddr_t orig_head = *head_blk;
1454
1455 error = xlog_verify_head(log, head_blk, tail_blk, bp,
1456 &rhead_blk, &rhead, &wrapped);
1457 if (error)
1458 goto done;
1459
1460 /* update in-core state again if the head changed */
1461 if (*head_blk != orig_head) {
1462 xlog_set_state(log, *head_blk, rhead, rhead_blk,
1463 wrapped);
1464 tail_lsn = atomic64_read(&log->l_tail_lsn);
1465 error = xlog_check_unmount_rec(log, head_blk, tail_blk,
1466 rhead, rhead_blk, bp,
1467 &clean);
1468 if (error)
1469 goto done;
1470 }
1471 }
1472
1473 /*
1474 * Note that the unmount was clean. If the unmount was not clean, we
1475 * need to know this to rebuild the superblock counters from the perag
1476 * headers if we have a filesystem using non-persistent counters.
1477 */
1478 if (clean)
1479 log->l_mp->m_flags |= XFS_MOUNT_WAS_CLEAN;
1480
1481 /*
1482 * Make sure that there are no blocks in front of the head
1483 * with the same cycle number as the head. This can happen
1484 * because we allow multiple outstanding log writes concurrently,
1485 * and the later writes might make it out before earlier ones.
1486 *
1487 * We use the lsn from before modifying it so that we'll never
1488 * overwrite the unmount record after a clean unmount.
1489 *
1490 * Do this only if we are going to recover the filesystem
1491 *
1492 * NOTE: This used to say "if (!readonly)"
1493 * However on Linux, we can & do recover a read-only filesystem.
1494 * We only skip recovery if NORECOVERY is specified on mount,
1495 * in which case we would not be here.
1496 *
1497 * But... if the -device- itself is readonly, just skip this.
1498 * We can't recover this device anyway, so it won't matter.
1499 */
1500 if (!xfs_readonly_buftarg(log->l_mp->m_logdev_targp))
1501 error = xlog_clear_stale_blocks(log, tail_lsn);
1502
1503done:
1504 xlog_put_bp(bp);
1505
1506 if (error)
1507 xfs_warn(log->l_mp, "failed to locate log tail");
1508 return error;
1509}
1510
1511/*
1512 * Is the log zeroed at all?
1513 *
1514 * The last binary search should be changed to perform an X block read
1515 * once X becomes small enough. You can then search linearly through
1516 * the X blocks. This will cut down on the number of reads we need to do.
1517 *
1518 * If the log is partially zeroed, this routine will pass back the blkno
1519 * of the first block with cycle number 0. It won't have a complete LR
1520 * preceding it.
1521 *
1522 * Return:
1523 * 0 => the log is completely written to
1524 * 1 => use *blk_no as the first block of the log
1525 * <0 => error has occurred
1526 */
1527STATIC int
1528xlog_find_zeroed(
1529 struct xlog *log,
1530 xfs_daddr_t *blk_no)
1531{
1532 xfs_buf_t *bp;
1533 char *offset;
1534 uint first_cycle, last_cycle;
1535 xfs_daddr_t new_blk, last_blk, start_blk;
1536 xfs_daddr_t num_scan_bblks;
1537 int error, log_bbnum = log->l_logBBsize;
1538
1539 *blk_no = 0;
1540
1541 /* check totally zeroed log */
1542 bp = xlog_get_bp(log, 1);
1543 if (!bp)
1544 return -ENOMEM;
1545 error = xlog_bread(log, 0, 1, bp, &offset);
1546 if (error)
1547 goto bp_err;
1548
1549 first_cycle = xlog_get_cycle(offset);
1550 if (first_cycle == 0) { /* completely zeroed log */
1551 *blk_no = 0;
1552 xlog_put_bp(bp);
1553 return 1;
1554 }
1555
1556 /* check partially zeroed log */
1557 error = xlog_bread(log, log_bbnum-1, 1, bp, &offset);
1558 if (error)
1559 goto bp_err;
1560
1561 last_cycle = xlog_get_cycle(offset);
1562 if (last_cycle != 0) { /* log completely written to */
1563 xlog_put_bp(bp);
1564 return 0;
1565 } else if (first_cycle != 1) {
1566 /*
1567 * If the cycle of the last block is zero, the cycle of
1568 * the first block must be 1. If it's not, maybe we're
1569 * not looking at a log... Bail out.
1570 */
1571 xfs_warn(log->l_mp,
1572 "Log inconsistent or not a log (last==0, first!=1)");
1573 error = -EINVAL;
1574 goto bp_err;
1575 }
1576
1577 /* we have a partially zeroed log */
1578 last_blk = log_bbnum-1;
1579 if ((error = xlog_find_cycle_start(log, bp, 0, &last_blk, 0)))
1580 goto bp_err;
1581
1582 /*
1583 * Validate the answer. Because there is no way to guarantee that
1584 * the entire log is made up of log records which are the same size,
1585 * we scan over the defined maximum blocks. At this point, the maximum
1586 * is not chosen to mean anything special. XXXmiken
1587 */
1588 num_scan_bblks = XLOG_TOTAL_REC_SHIFT(log);
1589 ASSERT(num_scan_bblks <= INT_MAX);
1590
1591 if (last_blk < num_scan_bblks)
1592 num_scan_bblks = last_blk;
1593 start_blk = last_blk - num_scan_bblks;
1594
1595 /*
1596 * We search for any instances of cycle number 0 that occur before
1597 * our current estimate of the head. What we're trying to detect is
1598 * 1 ... | 0 | 1 | 0...
1599 * ^ binary search ends here
1600 */
1601 if ((error = xlog_find_verify_cycle(log, start_blk,
1602 (int)num_scan_bblks, 0, &new_blk)))
1603 goto bp_err;
1604 if (new_blk != -1)
1605 last_blk = new_blk;
1606
1607 /*
1608 * Potentially backup over partial log record write. We don't need
1609 * to search the end of the log because we know it is zero.
1610 */
1611 error = xlog_find_verify_log_record(log, start_blk, &last_blk, 0);
1612 if (error == 1)
1613 error = -EIO;
1614 if (error)
1615 goto bp_err;
1616
1617 *blk_no = last_blk;
1618bp_err:
1619 xlog_put_bp(bp);
1620 if (error)
1621 return error;
1622 return 1;
1623}
1624
1625/*
1626 * These are simple subroutines used by xlog_clear_stale_blocks() below
1627 * to initialize a buffer full of empty log record headers and write
1628 * them into the log.
1629 */
1630STATIC void
1631xlog_add_record(
1632 struct xlog *log,
1633 char *buf,
1634 int cycle,
1635 int block,
1636 int tail_cycle,
1637 int tail_block)
1638{
1639 xlog_rec_header_t *recp = (xlog_rec_header_t *)buf;
1640
1641 memset(buf, 0, BBSIZE);
1642 recp->h_magicno = cpu_to_be32(XLOG_HEADER_MAGIC_NUM);
1643 recp->h_cycle = cpu_to_be32(cycle);
1644 recp->h_version = cpu_to_be32(
1645 xfs_sb_version_haslogv2(&log->l_mp->m_sb) ? 2 : 1);
1646 recp->h_lsn = cpu_to_be64(xlog_assign_lsn(cycle, block));
1647 recp->h_tail_lsn = cpu_to_be64(xlog_assign_lsn(tail_cycle, tail_block));
1648 recp->h_fmt = cpu_to_be32(XLOG_FMT);
1649 memcpy(&recp->h_fs_uuid, &log->l_mp->m_sb.sb_uuid, sizeof(uuid_t));
1650}
1651
1652STATIC int
1653xlog_write_log_records(
1654 struct xlog *log,
1655 int cycle,
1656 int start_block,
1657 int blocks,
1658 int tail_cycle,
1659 int tail_block)
1660{
1661 char *offset;
1662 xfs_buf_t *bp;
1663 int balign, ealign;
1664 int sectbb = log->l_sectBBsize;
1665 int end_block = start_block + blocks;
1666 int bufblks;
1667 int error = 0;
1668 int i, j = 0;
1669
1670 /*
1671 * Greedily allocate a buffer big enough to handle the full
1672 * range of basic blocks to be written. If that fails, try
1673 * a smaller size. We need to be able to write at least a
1674 * log sector, or we're out of luck.
1675 */
1676 bufblks = 1 << ffs(blocks);
1677 while (bufblks > log->l_logBBsize)
1678 bufblks >>= 1;
1679 while (!(bp = xlog_get_bp(log, bufblks))) {
1680 bufblks >>= 1;
1681 if (bufblks < sectbb)
1682 return -ENOMEM;
1683 }
1684
1685 /* We may need to do a read at the start to fill in part of
1686 * the buffer in the starting sector not covered by the first
1687 * write below.
1688 */
1689 balign = round_down(start_block, sectbb);
1690 if (balign != start_block) {
1691 error = xlog_bread_noalign(log, start_block, 1, bp);
1692 if (error)
1693 goto out_put_bp;
1694
1695 j = start_block - balign;
1696 }
1697
1698 for (i = start_block; i < end_block; i += bufblks) {
1699 int bcount, endcount;
1700
1701 bcount = min(bufblks, end_block - start_block);
1702 endcount = bcount - j;
1703
1704 /* We may need to do a read at the end to fill in part of
1705 * the buffer in the final sector not covered by the write.
1706 * If this is the same sector as the above read, skip it.
1707 */
1708 ealign = round_down(end_block, sectbb);
1709 if (j == 0 && (start_block + endcount > ealign)) {
1710 offset = bp->b_addr + BBTOB(ealign - start_block);
1711 error = xlog_bread_offset(log, ealign, sectbb,
1712 bp, offset);
1713 if (error)
1714 break;
1715
1716 }
1717
1718 offset = xlog_align(log, start_block, endcount, bp);
1719 for (; j < endcount; j++) {
1720 xlog_add_record(log, offset, cycle, i+j,
1721 tail_cycle, tail_block);
1722 offset += BBSIZE;
1723 }
1724 error = xlog_bwrite(log, start_block, endcount, bp);
1725 if (error)
1726 break;
1727 start_block += endcount;
1728 j = 0;
1729 }
1730
1731 out_put_bp:
1732 xlog_put_bp(bp);
1733 return error;
1734}
1735
1736/*
1737 * This routine is called to blow away any incomplete log writes out
1738 * in front of the log head. We do this so that we won't become confused
1739 * if we come up, write only a little bit more, and then crash again.
1740 * If we leave the partial log records out there, this situation could
1741 * cause us to think those partial writes are valid blocks since they
1742 * have the current cycle number. We get rid of them by overwriting them
1743 * with empty log records with the old cycle number rather than the
1744 * current one.
1745 *
1746 * The tail lsn is passed in rather than taken from
1747 * the log so that we will not write over the unmount record after a
1748 * clean unmount in a 512 block log. Doing so would leave the log without
1749 * any valid log records in it until a new one was written. If we crashed
1750 * during that time we would not be able to recover.
1751 */
1752STATIC int
1753xlog_clear_stale_blocks(
1754 struct xlog *log,
1755 xfs_lsn_t tail_lsn)
1756{
1757 int tail_cycle, head_cycle;
1758 int tail_block, head_block;
1759 int tail_distance, max_distance;
1760 int distance;
1761 int error;
1762
1763 tail_cycle = CYCLE_LSN(tail_lsn);
1764 tail_block = BLOCK_LSN(tail_lsn);
1765 head_cycle = log->l_curr_cycle;
1766 head_block = log->l_curr_block;
1767
1768 /*
1769 * Figure out the distance between the new head of the log
1770 * and the tail. We want to write over any blocks beyond the
1771 * head that we may have written just before the crash, but
1772 * we don't want to overwrite the tail of the log.
1773 */
1774 if (head_cycle == tail_cycle) {
1775 /*
1776 * The tail is behind the head in the physical log,
1777 * so the distance from the head to the tail is the
1778 * distance from the head to the end of the log plus
1779 * the distance from the beginning of the log to the
1780 * tail.
1781 */
1782 if (unlikely(head_block < tail_block || head_block >= log->l_logBBsize)) {
1783 XFS_ERROR_REPORT("xlog_clear_stale_blocks(1)",
1784 XFS_ERRLEVEL_LOW, log->l_mp);
1785 return -EFSCORRUPTED;
1786 }
1787 tail_distance = tail_block + (log->l_logBBsize - head_block);
1788 } else {
1789 /*
1790 * The head is behind the tail in the physical log,
1791 * so the distance from the head to the tail is just
1792 * the tail block minus the head block.
1793 */
1794 if (unlikely(head_block >= tail_block || head_cycle != (tail_cycle + 1))){
1795 XFS_ERROR_REPORT("xlog_clear_stale_blocks(2)",
1796 XFS_ERRLEVEL_LOW, log->l_mp);
1797 return -EFSCORRUPTED;
1798 }
1799 tail_distance = tail_block - head_block;
1800 }
1801
1802 /*
1803 * If the head is right up against the tail, we can't clear
1804 * anything.
1805 */
1806 if (tail_distance <= 0) {
1807 ASSERT(tail_distance == 0);
1808 return 0;
1809 }
1810
1811 max_distance = XLOG_TOTAL_REC_SHIFT(log);
1812 /*
1813 * Take the smaller of the maximum amount of outstanding I/O
1814 * we could have and the distance to the tail to clear out.
1815 * We take the smaller so that we don't overwrite the tail and
1816 * we don't waste all day writing from the head to the tail
1817 * for no reason.
1818 */
1819 max_distance = MIN(max_distance, tail_distance);
1820
1821 if ((head_block + max_distance) <= log->l_logBBsize) {
1822 /*
1823 * We can stomp all the blocks we need to without
1824 * wrapping around the end of the log. Just do it
1825 * in a single write. Use the cycle number of the
1826 * current cycle minus one so that the log will look like:
1827 * n ... | n - 1 ...
1828 */
1829 error = xlog_write_log_records(log, (head_cycle - 1),
1830 head_block, max_distance, tail_cycle,
1831 tail_block);
1832 if (error)
1833 return error;
1834 } else {
1835 /*
1836 * We need to wrap around the end of the physical log in
1837 * order to clear all the blocks. Do it in two separate
1838 * I/Os. The first write should be from the head to the
1839 * end of the physical log, and it should use the current
1840 * cycle number minus one just like above.
1841 */
1842 distance = log->l_logBBsize - head_block;
1843 error = xlog_write_log_records(log, (head_cycle - 1),
1844 head_block, distance, tail_cycle,
1845 tail_block);
1846
1847 if (error)
1848 return error;
1849
1850 /*
1851 * Now write the blocks at the start of the physical log.
1852 * This writes the remainder of the blocks we want to clear.
1853 * It uses the current cycle number since we're now on the
1854 * same cycle as the head so that we get:
1855 * n ... n ... | n - 1 ...
1856 * ^^^^^ blocks we're writing
1857 */
1858 distance = max_distance - (log->l_logBBsize - head_block);
1859 error = xlog_write_log_records(log, head_cycle, 0, distance,
1860 tail_cycle, tail_block);
1861 if (error)
1862 return error;
1863 }
1864
1865 return 0;
1866}
1867
1868/******************************************************************************
1869 *
1870 * Log recover routines
1871 *
1872 ******************************************************************************
1873 */
1874
1875/*
1876 * Sort the log items in the transaction.
1877 *
1878 * The ordering constraints are defined by the inode allocation and unlink
1879 * behaviour. The rules are:
1880 *
1881 * 1. Every item is only logged once in a given transaction. Hence it
1882 * represents the last logged state of the item. Hence ordering is
1883 * dependent on the order in which operations need to be performed so
1884 * required initial conditions are always met.
1885 *
1886 * 2. Cancelled buffers are recorded in pass 1 in a separate table and
1887 * there's nothing to replay from them so we can simply cull them
1888 * from the transaction. However, we can't do that until after we've
1889 * replayed all the other items because they may be dependent on the
1890 * cancelled buffer and replaying the cancelled buffer can remove it
1891 * form the cancelled buffer table. Hence they have tobe done last.
1892 *
1893 * 3. Inode allocation buffers must be replayed before inode items that
1894 * read the buffer and replay changes into it. For filesystems using the
1895 * ICREATE transactions, this means XFS_LI_ICREATE objects need to get
1896 * treated the same as inode allocation buffers as they create and
1897 * initialise the buffers directly.
1898 *
1899 * 4. Inode unlink buffers must be replayed after inode items are replayed.
1900 * This ensures that inodes are completely flushed to the inode buffer
1901 * in a "free" state before we remove the unlinked inode list pointer.
1902 *
1903 * Hence the ordering needs to be inode allocation buffers first, inode items
1904 * second, inode unlink buffers third and cancelled buffers last.
1905 *
1906 * But there's a problem with that - we can't tell an inode allocation buffer
1907 * apart from a regular buffer, so we can't separate them. We can, however,
1908 * tell an inode unlink buffer from the others, and so we can separate them out
1909 * from all the other buffers and move them to last.
1910 *
1911 * Hence, 4 lists, in order from head to tail:
1912 * - buffer_list for all buffers except cancelled/inode unlink buffers
1913 * - item_list for all non-buffer items
1914 * - inode_buffer_list for inode unlink buffers
1915 * - cancel_list for the cancelled buffers
1916 *
1917 * Note that we add objects to the tail of the lists so that first-to-last
1918 * ordering is preserved within the lists. Adding objects to the head of the
1919 * list means when we traverse from the head we walk them in last-to-first
1920 * order. For cancelled buffers and inode unlink buffers this doesn't matter,
1921 * but for all other items there may be specific ordering that we need to
1922 * preserve.
1923 */
1924STATIC int
1925xlog_recover_reorder_trans(
1926 struct xlog *log,
1927 struct xlog_recover *trans,
1928 int pass)
1929{
1930 xlog_recover_item_t *item, *n;
1931 int error = 0;
1932 LIST_HEAD(sort_list);
1933 LIST_HEAD(cancel_list);
1934 LIST_HEAD(buffer_list);
1935 LIST_HEAD(inode_buffer_list);
1936 LIST_HEAD(inode_list);
1937
1938 list_splice_init(&trans->r_itemq, &sort_list);
1939 list_for_each_entry_safe(item, n, &sort_list, ri_list) {
1940 xfs_buf_log_format_t *buf_f = item->ri_buf[0].i_addr;
1941
1942 switch (ITEM_TYPE(item)) {
1943 case XFS_LI_ICREATE:
1944 list_move_tail(&item->ri_list, &buffer_list);
1945 break;
1946 case XFS_LI_BUF:
1947 if (buf_f->blf_flags & XFS_BLF_CANCEL) {
1948 trace_xfs_log_recover_item_reorder_head(log,
1949 trans, item, pass);
1950 list_move(&item->ri_list, &cancel_list);
1951 break;
1952 }
1953 if (buf_f->blf_flags & XFS_BLF_INODE_BUF) {
1954 list_move(&item->ri_list, &inode_buffer_list);
1955 break;
1956 }
1957 list_move_tail(&item->ri_list, &buffer_list);
1958 break;
1959 case XFS_LI_INODE:
1960 case XFS_LI_DQUOT:
1961 case XFS_LI_QUOTAOFF:
1962 case XFS_LI_EFD:
1963 case XFS_LI_EFI:
1964 case XFS_LI_RUI:
1965 case XFS_LI_RUD:
1966 case XFS_LI_CUI:
1967 case XFS_LI_CUD:
1968 case XFS_LI_BUI:
1969 case XFS_LI_BUD:
1970 trace_xfs_log_recover_item_reorder_tail(log,
1971 trans, item, pass);
1972 list_move_tail(&item->ri_list, &inode_list);
1973 break;
1974 default:
1975 xfs_warn(log->l_mp,
1976 "%s: unrecognized type of log operation",
1977 __func__);
1978 ASSERT(0);
1979 /*
1980 * return the remaining items back to the transaction
1981 * item list so they can be freed in caller.
1982 */
1983 if (!list_empty(&sort_list))
1984 list_splice_init(&sort_list, &trans->r_itemq);
1985 error = -EIO;
1986 goto out;
1987 }
1988 }
1989out:
1990 ASSERT(list_empty(&sort_list));
1991 if (!list_empty(&buffer_list))
1992 list_splice(&buffer_list, &trans->r_itemq);
1993 if (!list_empty(&inode_list))
1994 list_splice_tail(&inode_list, &trans->r_itemq);
1995 if (!list_empty(&inode_buffer_list))
1996 list_splice_tail(&inode_buffer_list, &trans->r_itemq);
1997 if (!list_empty(&cancel_list))
1998 list_splice_tail(&cancel_list, &trans->r_itemq);
1999 return error;
2000}
2001
2002/*
2003 * Build up the table of buf cancel records so that we don't replay
2004 * cancelled data in the second pass. For buffer records that are
2005 * not cancel records, there is nothing to do here so we just return.
2006 *
2007 * If we get a cancel record which is already in the table, this indicates
2008 * that the buffer was cancelled multiple times. In order to ensure
2009 * that during pass 2 we keep the record in the table until we reach its
2010 * last occurrence in the log, we keep a reference count in the cancel
2011 * record in the table to tell us how many times we expect to see this
2012 * record during the second pass.
2013 */
2014STATIC int
2015xlog_recover_buffer_pass1(
2016 struct xlog *log,
2017 struct xlog_recover_item *item)
2018{
2019 xfs_buf_log_format_t *buf_f = item->ri_buf[0].i_addr;
2020 struct list_head *bucket;
2021 struct xfs_buf_cancel *bcp;
2022
2023 /*
2024 * If this isn't a cancel buffer item, then just return.
2025 */
2026 if (!(buf_f->blf_flags & XFS_BLF_CANCEL)) {
2027 trace_xfs_log_recover_buf_not_cancel(log, buf_f);
2028 return 0;
2029 }
2030
2031 /*
2032 * Insert an xfs_buf_cancel record into the hash table of them.
2033 * If there is already an identical record, bump its reference count.
2034 */
2035 bucket = XLOG_BUF_CANCEL_BUCKET(log, buf_f->blf_blkno);
2036 list_for_each_entry(bcp, bucket, bc_list) {
2037 if (bcp->bc_blkno == buf_f->blf_blkno &&
2038 bcp->bc_len == buf_f->blf_len) {
2039 bcp->bc_refcount++;
2040 trace_xfs_log_recover_buf_cancel_ref_inc(log, buf_f);
2041 return 0;
2042 }
2043 }
2044
2045 bcp = kmem_alloc(sizeof(struct xfs_buf_cancel), KM_SLEEP);
2046 bcp->bc_blkno = buf_f->blf_blkno;
2047 bcp->bc_len = buf_f->blf_len;
2048 bcp->bc_refcount = 1;
2049 list_add_tail(&bcp->bc_list, bucket);
2050
2051 trace_xfs_log_recover_buf_cancel_add(log, buf_f);
2052 return 0;
2053}
2054
2055/*
2056 * Check to see whether the buffer being recovered has a corresponding
2057 * entry in the buffer cancel record table. If it is, return the cancel
2058 * buffer structure to the caller.
2059 */
2060STATIC struct xfs_buf_cancel *
2061xlog_peek_buffer_cancelled(
2062 struct xlog *log,
2063 xfs_daddr_t blkno,
2064 uint len,
2065 unsigned short flags)
2066{
2067 struct list_head *bucket;
2068 struct xfs_buf_cancel *bcp;
2069
2070 if (!log->l_buf_cancel_table) {
2071 /* empty table means no cancelled buffers in the log */
2072 ASSERT(!(flags & XFS_BLF_CANCEL));
2073 return NULL;
2074 }
2075
2076 bucket = XLOG_BUF_CANCEL_BUCKET(log, blkno);
2077 list_for_each_entry(bcp, bucket, bc_list) {
2078 if (bcp->bc_blkno == blkno && bcp->bc_len == len)
2079 return bcp;
2080 }
2081
2082 /*
2083 * We didn't find a corresponding entry in the table, so return 0 so
2084 * that the buffer is NOT cancelled.
2085 */
2086 ASSERT(!(flags & XFS_BLF_CANCEL));
2087 return NULL;
2088}
2089
2090/*
2091 * If the buffer is being cancelled then return 1 so that it will be cancelled,
2092 * otherwise return 0. If the buffer is actually a buffer cancel item
2093 * (XFS_BLF_CANCEL is set), then decrement the refcount on the entry in the
2094 * table and remove it from the table if this is the last reference.
2095 *
2096 * We remove the cancel record from the table when we encounter its last
2097 * occurrence in the log so that if the same buffer is re-used again after its
2098 * last cancellation we actually replay the changes made at that point.
2099 */
2100STATIC int
2101xlog_check_buffer_cancelled(
2102 struct xlog *log,
2103 xfs_daddr_t blkno,
2104 uint len,
2105 unsigned short flags)
2106{
2107 struct xfs_buf_cancel *bcp;
2108
2109 bcp = xlog_peek_buffer_cancelled(log, blkno, len, flags);
2110 if (!bcp)
2111 return 0;
2112
2113 /*
2114 * We've go a match, so return 1 so that the recovery of this buffer
2115 * is cancelled. If this buffer is actually a buffer cancel log
2116 * item, then decrement the refcount on the one in the table and
2117 * remove it if this is the last reference.
2118 */
2119 if (flags & XFS_BLF_CANCEL) {
2120 if (--bcp->bc_refcount == 0) {
2121 list_del(&bcp->bc_list);
2122 kmem_free(bcp);
2123 }
2124 }
2125 return 1;
2126}
2127
2128/*
2129 * Perform recovery for a buffer full of inodes. In these buffers, the only
2130 * data which should be recovered is that which corresponds to the
2131 * di_next_unlinked pointers in the on disk inode structures. The rest of the
2132 * data for the inodes is always logged through the inodes themselves rather
2133 * than the inode buffer and is recovered in xlog_recover_inode_pass2().
2134 *
2135 * The only time when buffers full of inodes are fully recovered is when the
2136 * buffer is full of newly allocated inodes. In this case the buffer will
2137 * not be marked as an inode buffer and so will be sent to
2138 * xlog_recover_do_reg_buffer() below during recovery.
2139 */
2140STATIC int
2141xlog_recover_do_inode_buffer(
2142 struct xfs_mount *mp,
2143 xlog_recover_item_t *item,
2144 struct xfs_buf *bp,
2145 xfs_buf_log_format_t *buf_f)
2146{
2147 int i;
2148 int item_index = 0;
2149 int bit = 0;
2150 int nbits = 0;
2151 int reg_buf_offset = 0;
2152 int reg_buf_bytes = 0;
2153 int next_unlinked_offset;
2154 int inodes_per_buf;
2155 xfs_agino_t *logged_nextp;
2156 xfs_agino_t *buffer_nextp;
2157
2158 trace_xfs_log_recover_buf_inode_buf(mp->m_log, buf_f);
2159
2160 /*
2161 * Post recovery validation only works properly on CRC enabled
2162 * filesystems.
2163 */
2164 if (xfs_sb_version_hascrc(&mp->m_sb))
2165 bp->b_ops = &xfs_inode_buf_ops;
2166
2167 inodes_per_buf = BBTOB(bp->b_io_length) >> mp->m_sb.sb_inodelog;
2168 for (i = 0; i < inodes_per_buf; i++) {
2169 next_unlinked_offset = (i * mp->m_sb.sb_inodesize) +
2170 offsetof(xfs_dinode_t, di_next_unlinked);
2171
2172 while (next_unlinked_offset >=
2173 (reg_buf_offset + reg_buf_bytes)) {
2174 /*
2175 * The next di_next_unlinked field is beyond
2176 * the current logged region. Find the next
2177 * logged region that contains or is beyond
2178 * the current di_next_unlinked field.
2179 */
2180 bit += nbits;
2181 bit = xfs_next_bit(buf_f->blf_data_map,
2182 buf_f->blf_map_size, bit);
2183
2184 /*
2185 * If there are no more logged regions in the
2186 * buffer, then we're done.
2187 */
2188 if (bit == -1)
2189 return 0;
2190
2191 nbits = xfs_contig_bits(buf_f->blf_data_map,
2192 buf_f->blf_map_size, bit);
2193 ASSERT(nbits > 0);
2194 reg_buf_offset = bit << XFS_BLF_SHIFT;
2195 reg_buf_bytes = nbits << XFS_BLF_SHIFT;
2196 item_index++;
2197 }
2198
2199 /*
2200 * If the current logged region starts after the current
2201 * di_next_unlinked field, then move on to the next
2202 * di_next_unlinked field.
2203 */
2204 if (next_unlinked_offset < reg_buf_offset)
2205 continue;
2206
2207 ASSERT(item->ri_buf[item_index].i_addr != NULL);
2208 ASSERT((item->ri_buf[item_index].i_len % XFS_BLF_CHUNK) == 0);
2209 ASSERT((reg_buf_offset + reg_buf_bytes) <=
2210 BBTOB(bp->b_io_length));
2211
2212 /*
2213 * The current logged region contains a copy of the
2214 * current di_next_unlinked field. Extract its value
2215 * and copy it to the buffer copy.
2216 */
2217 logged_nextp = item->ri_buf[item_index].i_addr +
2218 next_unlinked_offset - reg_buf_offset;
2219 if (unlikely(*logged_nextp == 0)) {
2220 xfs_alert(mp,
2221 "Bad inode buffer log record (ptr = "PTR_FMT", bp = "PTR_FMT"). "
2222 "Trying to replay bad (0) inode di_next_unlinked field.",
2223 item, bp);
2224 XFS_ERROR_REPORT("xlog_recover_do_inode_buf",
2225 XFS_ERRLEVEL_LOW, mp);
2226 return -EFSCORRUPTED;
2227 }
2228
2229 buffer_nextp = xfs_buf_offset(bp, next_unlinked_offset);
2230 *buffer_nextp = *logged_nextp;
2231
2232 /*
2233 * If necessary, recalculate the CRC in the on-disk inode. We
2234 * have to leave the inode in a consistent state for whoever
2235 * reads it next....
2236 */
2237 xfs_dinode_calc_crc(mp,
2238 xfs_buf_offset(bp, i * mp->m_sb.sb_inodesize));
2239
2240 }
2241
2242 return 0;
2243}
2244
2245/*
2246 * V5 filesystems know the age of the buffer on disk being recovered. We can
2247 * have newer objects on disk than we are replaying, and so for these cases we
2248 * don't want to replay the current change as that will make the buffer contents
2249 * temporarily invalid on disk.
2250 *
2251 * The magic number might not match the buffer type we are going to recover
2252 * (e.g. reallocated blocks), so we ignore the xfs_buf_log_format flags. Hence
2253 * extract the LSN of the existing object in the buffer based on it's current
2254 * magic number. If we don't recognise the magic number in the buffer, then
2255 * return a LSN of -1 so that the caller knows it was an unrecognised block and
2256 * so can recover the buffer.
2257 *
2258 * Note: we cannot rely solely on magic number matches to determine that the
2259 * buffer has a valid LSN - we also need to verify that it belongs to this
2260 * filesystem, so we need to extract the object's LSN and compare it to that
2261 * which we read from the superblock. If the UUIDs don't match, then we've got a
2262 * stale metadata block from an old filesystem instance that we need to recover
2263 * over the top of.
2264 */
2265static xfs_lsn_t
2266xlog_recover_get_buf_lsn(
2267 struct xfs_mount *mp,
2268 struct xfs_buf *bp)
2269{
2270 uint32_t magic32;
2271 uint16_t magic16;
2272 uint16_t magicda;
2273 void *blk = bp->b_addr;
2274 uuid_t *uuid;
2275 xfs_lsn_t lsn = -1;
2276
2277 /* v4 filesystems always recover immediately */
2278 if (!xfs_sb_version_hascrc(&mp->m_sb))
2279 goto recover_immediately;
2280
2281 magic32 = be32_to_cpu(*(__be32 *)blk);
2282 switch (magic32) {
2283 case XFS_ABTB_CRC_MAGIC:
2284 case XFS_ABTC_CRC_MAGIC:
2285 case XFS_ABTB_MAGIC:
2286 case XFS_ABTC_MAGIC:
2287 case XFS_RMAP_CRC_MAGIC:
2288 case XFS_REFC_CRC_MAGIC:
2289 case XFS_IBT_CRC_MAGIC:
2290 case XFS_IBT_MAGIC: {
2291 struct xfs_btree_block *btb = blk;
2292
2293 lsn = be64_to_cpu(btb->bb_u.s.bb_lsn);
2294 uuid = &btb->bb_u.s.bb_uuid;
2295 break;
2296 }
2297 case XFS_BMAP_CRC_MAGIC:
2298 case XFS_BMAP_MAGIC: {
2299 struct xfs_btree_block *btb = blk;
2300
2301 lsn = be64_to_cpu(btb->bb_u.l.bb_lsn);
2302 uuid = &btb->bb_u.l.bb_uuid;
2303 break;
2304 }
2305 case XFS_AGF_MAGIC:
2306 lsn = be64_to_cpu(((struct xfs_agf *)blk)->agf_lsn);
2307 uuid = &((struct xfs_agf *)blk)->agf_uuid;
2308 break;
2309 case XFS_AGFL_MAGIC:
2310 lsn = be64_to_cpu(((struct xfs_agfl *)blk)->agfl_lsn);
2311 uuid = &((struct xfs_agfl *)blk)->agfl_uuid;
2312 break;
2313 case XFS_AGI_MAGIC:
2314 lsn = be64_to_cpu(((struct xfs_agi *)blk)->agi_lsn);
2315 uuid = &((struct xfs_agi *)blk)->agi_uuid;
2316 break;
2317 case XFS_SYMLINK_MAGIC:
2318 lsn = be64_to_cpu(((struct xfs_dsymlink_hdr *)blk)->sl_lsn);
2319 uuid = &((struct xfs_dsymlink_hdr *)blk)->sl_uuid;
2320 break;
2321 case XFS_DIR3_BLOCK_MAGIC:
2322 case XFS_DIR3_DATA_MAGIC:
2323 case XFS_DIR3_FREE_MAGIC:
2324 lsn = be64_to_cpu(((struct xfs_dir3_blk_hdr *)blk)->lsn);
2325 uuid = &((struct xfs_dir3_blk_hdr *)blk)->uuid;
2326 break;
2327 case XFS_ATTR3_RMT_MAGIC:
2328 /*
2329 * Remote attr blocks are written synchronously, rather than
2330 * being logged. That means they do not contain a valid LSN
2331 * (i.e. transactionally ordered) in them, and hence any time we
2332 * see a buffer to replay over the top of a remote attribute
2333 * block we should simply do so.
2334 */
2335 goto recover_immediately;
2336 case XFS_SB_MAGIC:
2337 /*
2338 * superblock uuids are magic. We may or may not have a
2339 * sb_meta_uuid on disk, but it will be set in the in-core
2340 * superblock. We set the uuid pointer for verification
2341 * according to the superblock feature mask to ensure we check
2342 * the relevant UUID in the superblock.
2343 */
2344 lsn = be64_to_cpu(((struct xfs_dsb *)blk)->sb_lsn);
2345 if (xfs_sb_version_hasmetauuid(&mp->m_sb))
2346 uuid = &((struct xfs_dsb *)blk)->sb_meta_uuid;
2347 else
2348 uuid = &((struct xfs_dsb *)blk)->sb_uuid;
2349 break;
2350 default:
2351 break;
2352 }
2353
2354 if (lsn != (xfs_lsn_t)-1) {
2355 if (!uuid_equal(&mp->m_sb.sb_meta_uuid, uuid))
2356 goto recover_immediately;
2357 return lsn;
2358 }
2359
2360 magicda = be16_to_cpu(((struct xfs_da_blkinfo *)blk)->magic);
2361 switch (magicda) {
2362 case XFS_DIR3_LEAF1_MAGIC:
2363 case XFS_DIR3_LEAFN_MAGIC:
2364 case XFS_DA3_NODE_MAGIC:
2365 lsn = be64_to_cpu(((struct xfs_da3_blkinfo *)blk)->lsn);
2366 uuid = &((struct xfs_da3_blkinfo *)blk)->uuid;
2367 break;
2368 default:
2369 break;
2370 }
2371
2372 if (lsn != (xfs_lsn_t)-1) {
2373 if (!uuid_equal(&mp->m_sb.sb_uuid, uuid))
2374 goto recover_immediately;
2375 return lsn;
2376 }
2377
2378 /*
2379 * We do individual object checks on dquot and inode buffers as they
2380 * have their own individual LSN records. Also, we could have a stale
2381 * buffer here, so we have to at least recognise these buffer types.
2382 *
2383 * A notd complexity here is inode unlinked list processing - it logs
2384 * the inode directly in the buffer, but we don't know which inodes have
2385 * been modified, and there is no global buffer LSN. Hence we need to
2386 * recover all inode buffer types immediately. This problem will be
2387 * fixed by logical logging of the unlinked list modifications.
2388 */
2389 magic16 = be16_to_cpu(*(__be16 *)blk);
2390 switch (magic16) {
2391 case XFS_DQUOT_MAGIC:
2392 case XFS_DINODE_MAGIC:
2393 goto recover_immediately;
2394 default:
2395 break;
2396 }
2397
2398 /* unknown buffer contents, recover immediately */
2399
2400recover_immediately:
2401 return (xfs_lsn_t)-1;
2402
2403}
2404
2405/*
2406 * Validate the recovered buffer is of the correct type and attach the
2407 * appropriate buffer operations to them for writeback. Magic numbers are in a
2408 * few places:
2409 * the first 16 bits of the buffer (inode buffer, dquot buffer),
2410 * the first 32 bits of the buffer (most blocks),
2411 * inside a struct xfs_da_blkinfo at the start of the buffer.
2412 */
2413static void
2414xlog_recover_validate_buf_type(
2415 struct xfs_mount *mp,
2416 struct xfs_buf *bp,
2417 xfs_buf_log_format_t *buf_f,
2418 xfs_lsn_t current_lsn)
2419{
2420 struct xfs_da_blkinfo *info = bp->b_addr;
2421 uint32_t magic32;
2422 uint16_t magic16;
2423 uint16_t magicda;
2424 char *warnmsg = NULL;
2425
2426 /*
2427 * We can only do post recovery validation on items on CRC enabled
2428 * fielsystems as we need to know when the buffer was written to be able
2429 * to determine if we should have replayed the item. If we replay old
2430 * metadata over a newer buffer, then it will enter a temporarily
2431 * inconsistent state resulting in verification failures. Hence for now
2432 * just avoid the verification stage for non-crc filesystems
2433 */
2434 if (!xfs_sb_version_hascrc(&mp->m_sb))
2435 return;
2436
2437 magic32 = be32_to_cpu(*(__be32 *)bp->b_addr);
2438 magic16 = be16_to_cpu(*(__be16*)bp->b_addr);
2439 magicda = be16_to_cpu(info->magic);
2440 switch (xfs_blft_from_flags(buf_f)) {
2441 case XFS_BLFT_BTREE_BUF:
2442 switch (magic32) {
2443 case XFS_ABTB_CRC_MAGIC:
2444 case XFS_ABTC_CRC_MAGIC:
2445 case XFS_ABTB_MAGIC:
2446 case XFS_ABTC_MAGIC:
2447 bp->b_ops = &xfs_allocbt_buf_ops;
2448 break;
2449 case XFS_IBT_CRC_MAGIC:
2450 case XFS_FIBT_CRC_MAGIC:
2451 case XFS_IBT_MAGIC:
2452 case XFS_FIBT_MAGIC:
2453 bp->b_ops = &xfs_inobt_buf_ops;
2454 break;
2455 case XFS_BMAP_CRC_MAGIC:
2456 case XFS_BMAP_MAGIC:
2457 bp->b_ops = &xfs_bmbt_buf_ops;
2458 break;
2459 case XFS_RMAP_CRC_MAGIC:
2460 bp->b_ops = &xfs_rmapbt_buf_ops;
2461 break;
2462 case XFS_REFC_CRC_MAGIC:
2463 bp->b_ops = &xfs_refcountbt_buf_ops;
2464 break;
2465 default:
2466 warnmsg = "Bad btree block magic!";
2467 break;
2468 }
2469 break;
2470 case XFS_BLFT_AGF_BUF:
2471 if (magic32 != XFS_AGF_MAGIC) {
2472 warnmsg = "Bad AGF block magic!";
2473 break;
2474 }
2475 bp->b_ops = &xfs_agf_buf_ops;
2476 break;
2477 case XFS_BLFT_AGFL_BUF:
2478 if (magic32 != XFS_AGFL_MAGIC) {
2479 warnmsg = "Bad AGFL block magic!";
2480 break;
2481 }
2482 bp->b_ops = &xfs_agfl_buf_ops;
2483 break;
2484 case XFS_BLFT_AGI_BUF:
2485 if (magic32 != XFS_AGI_MAGIC) {
2486 warnmsg = "Bad AGI block magic!";
2487 break;
2488 }
2489 bp->b_ops = &xfs_agi_buf_ops;
2490 break;
2491 case XFS_BLFT_UDQUOT_BUF:
2492 case XFS_BLFT_PDQUOT_BUF:
2493 case XFS_BLFT_GDQUOT_BUF:
2494#ifdef CONFIG_XFS_QUOTA
2495 if (magic16 != XFS_DQUOT_MAGIC) {
2496 warnmsg = "Bad DQUOT block magic!";
2497 break;
2498 }
2499 bp->b_ops = &xfs_dquot_buf_ops;
2500#else
2501 xfs_alert(mp,
2502 "Trying to recover dquots without QUOTA support built in!");
2503 ASSERT(0);
2504#endif
2505 break;
2506 case XFS_BLFT_DINO_BUF:
2507 if (magic16 != XFS_DINODE_MAGIC) {
2508 warnmsg = "Bad INODE block magic!";
2509 break;
2510 }
2511 bp->b_ops = &xfs_inode_buf_ops;
2512 break;
2513 case XFS_BLFT_SYMLINK_BUF:
2514 if (magic32 != XFS_SYMLINK_MAGIC) {
2515 warnmsg = "Bad symlink block magic!";
2516 break;
2517 }
2518 bp->b_ops = &xfs_symlink_buf_ops;
2519 break;
2520 case XFS_BLFT_DIR_BLOCK_BUF:
2521 if (magic32 != XFS_DIR2_BLOCK_MAGIC &&
2522 magic32 != XFS_DIR3_BLOCK_MAGIC) {
2523 warnmsg = "Bad dir block magic!";
2524 break;
2525 }
2526 bp->b_ops = &xfs_dir3_block_buf_ops;
2527 break;
2528 case XFS_BLFT_DIR_DATA_BUF:
2529 if (magic32 != XFS_DIR2_DATA_MAGIC &&
2530 magic32 != XFS_DIR3_DATA_MAGIC) {
2531 warnmsg = "Bad dir data magic!";
2532 break;
2533 }
2534 bp->b_ops = &xfs_dir3_data_buf_ops;
2535 break;
2536 case XFS_BLFT_DIR_FREE_BUF:
2537 if (magic32 != XFS_DIR2_FREE_MAGIC &&
2538 magic32 != XFS_DIR3_FREE_MAGIC) {
2539 warnmsg = "Bad dir3 free magic!";
2540 break;
2541 }
2542 bp->b_ops = &xfs_dir3_free_buf_ops;
2543 break;
2544 case XFS_BLFT_DIR_LEAF1_BUF:
2545 if (magicda != XFS_DIR2_LEAF1_MAGIC &&
2546 magicda != XFS_DIR3_LEAF1_MAGIC) {
2547 warnmsg = "Bad dir leaf1 magic!";
2548 break;
2549 }
2550 bp->b_ops = &xfs_dir3_leaf1_buf_ops;
2551 break;
2552 case XFS_BLFT_DIR_LEAFN_BUF:
2553 if (magicda != XFS_DIR2_LEAFN_MAGIC &&
2554 magicda != XFS_DIR3_LEAFN_MAGIC) {
2555 warnmsg = "Bad dir leafn magic!";
2556 break;
2557 }
2558 bp->b_ops = &xfs_dir3_leafn_buf_ops;
2559 break;
2560 case XFS_BLFT_DA_NODE_BUF:
2561 if (magicda != XFS_DA_NODE_MAGIC &&
2562 magicda != XFS_DA3_NODE_MAGIC) {
2563 warnmsg = "Bad da node magic!";
2564 break;
2565 }
2566 bp->b_ops = &xfs_da3_node_buf_ops;
2567 break;
2568 case XFS_BLFT_ATTR_LEAF_BUF:
2569 if (magicda != XFS_ATTR_LEAF_MAGIC &&
2570 magicda != XFS_ATTR3_LEAF_MAGIC) {
2571 warnmsg = "Bad attr leaf magic!";
2572 break;
2573 }
2574 bp->b_ops = &xfs_attr3_leaf_buf_ops;
2575 break;
2576 case XFS_BLFT_ATTR_RMT_BUF:
2577 if (magic32 != XFS_ATTR3_RMT_MAGIC) {
2578 warnmsg = "Bad attr remote magic!";
2579 break;
2580 }
2581 bp->b_ops = &xfs_attr3_rmt_buf_ops;
2582 break;
2583 case XFS_BLFT_SB_BUF:
2584 if (magic32 != XFS_SB_MAGIC) {
2585 warnmsg = "Bad SB block magic!";
2586 break;
2587 }
2588 bp->b_ops = &xfs_sb_buf_ops;
2589 break;
2590#ifdef CONFIG_XFS_RT
2591 case XFS_BLFT_RTBITMAP_BUF:
2592 case XFS_BLFT_RTSUMMARY_BUF:
2593 /* no magic numbers for verification of RT buffers */
2594 bp->b_ops = &xfs_rtbuf_ops;
2595 break;
2596#endif /* CONFIG_XFS_RT */
2597 default:
2598 xfs_warn(mp, "Unknown buffer type %d!",
2599 xfs_blft_from_flags(buf_f));
2600 break;
2601 }
2602
2603 /*
2604 * Nothing else to do in the case of a NULL current LSN as this means
2605 * the buffer is more recent than the change in the log and will be
2606 * skipped.
2607 */
2608 if (current_lsn == NULLCOMMITLSN)
2609 return;
2610
2611 if (warnmsg) {
2612 xfs_warn(mp, warnmsg);
2613 ASSERT(0);
2614 }
2615
2616 /*
2617 * We must update the metadata LSN of the buffer as it is written out to
2618 * ensure that older transactions never replay over this one and corrupt
2619 * the buffer. This can occur if log recovery is interrupted at some
2620 * point after the current transaction completes, at which point a
2621 * subsequent mount starts recovery from the beginning.
2622 *
2623 * Write verifiers update the metadata LSN from log items attached to
2624 * the buffer. Therefore, initialize a bli purely to carry the LSN to
2625 * the verifier. We'll clean it up in our ->iodone() callback.
2626 */
2627 if (bp->b_ops) {
2628 struct xfs_buf_log_item *bip;
2629
2630 ASSERT(!bp->b_iodone || bp->b_iodone == xlog_recover_iodone);
2631 bp->b_iodone = xlog_recover_iodone;
2632 xfs_buf_item_init(bp, mp);
2633 bip = bp->b_log_item;
2634 bip->bli_item.li_lsn = current_lsn;
2635 }
2636}
2637
2638/*
2639 * Perform a 'normal' buffer recovery. Each logged region of the
2640 * buffer should be copied over the corresponding region in the
2641 * given buffer. The bitmap in the buf log format structure indicates
2642 * where to place the logged data.
2643 */
2644STATIC void
2645xlog_recover_do_reg_buffer(
2646 struct xfs_mount *mp,
2647 xlog_recover_item_t *item,
2648 struct xfs_buf *bp,
2649 xfs_buf_log_format_t *buf_f,
2650 xfs_lsn_t current_lsn)
2651{
2652 int i;
2653 int bit;
2654 int nbits;
2655 xfs_failaddr_t fa;
2656
2657 trace_xfs_log_recover_buf_reg_buf(mp->m_log, buf_f);
2658
2659 bit = 0;
2660 i = 1; /* 0 is the buf format structure */
2661 while (1) {
2662 bit = xfs_next_bit(buf_f->blf_data_map,
2663 buf_f->blf_map_size, bit);
2664 if (bit == -1)
2665 break;
2666 nbits = xfs_contig_bits(buf_f->blf_data_map,
2667 buf_f->blf_map_size, bit);
2668 ASSERT(nbits > 0);
2669 ASSERT(item->ri_buf[i].i_addr != NULL);
2670 ASSERT(item->ri_buf[i].i_len % XFS_BLF_CHUNK == 0);
2671 ASSERT(BBTOB(bp->b_io_length) >=
2672 ((uint)bit << XFS_BLF_SHIFT) + (nbits << XFS_BLF_SHIFT));
2673
2674 /*
2675 * The dirty regions logged in the buffer, even though
2676 * contiguous, may span multiple chunks. This is because the
2677 * dirty region may span a physical page boundary in a buffer
2678 * and hence be split into two separate vectors for writing into
2679 * the log. Hence we need to trim nbits back to the length of
2680 * the current region being copied out of the log.
2681 */
2682 if (item->ri_buf[i].i_len < (nbits << XFS_BLF_SHIFT))
2683 nbits = item->ri_buf[i].i_len >> XFS_BLF_SHIFT;
2684
2685 /*
2686 * Do a sanity check if this is a dquot buffer. Just checking
2687 * the first dquot in the buffer should do. XXXThis is
2688 * probably a good thing to do for other buf types also.
2689 */
2690 fa = NULL;
2691 if (buf_f->blf_flags &
2692 (XFS_BLF_UDQUOT_BUF|XFS_BLF_PDQUOT_BUF|XFS_BLF_GDQUOT_BUF)) {
2693 if (item->ri_buf[i].i_addr == NULL) {
2694 xfs_alert(mp,
2695 "XFS: NULL dquot in %s.", __func__);
2696 goto next;
2697 }
2698 if (item->ri_buf[i].i_len < sizeof(xfs_disk_dquot_t)) {
2699 xfs_alert(mp,
2700 "XFS: dquot too small (%d) in %s.",
2701 item->ri_buf[i].i_len, __func__);
2702 goto next;
2703 }
2704 fa = xfs_dquot_verify(mp, item->ri_buf[i].i_addr,
2705 -1, 0, 0);
2706 if (fa) {
2707 xfs_alert(mp,
2708 "dquot corrupt at %pS trying to replay into block 0x%llx",
2709 fa, bp->b_bn);
2710 goto next;
2711 }
2712 }
2713
2714 memcpy(xfs_buf_offset(bp,
2715 (uint)bit << XFS_BLF_SHIFT), /* dest */
2716 item->ri_buf[i].i_addr, /* source */
2717 nbits<<XFS_BLF_SHIFT); /* length */
2718 next:
2719 i++;
2720 bit += nbits;
2721 }
2722
2723 /* Shouldn't be any more regions */
2724 ASSERT(i == item->ri_total);
2725
2726 xlog_recover_validate_buf_type(mp, bp, buf_f, current_lsn);
2727}
2728
2729/*
2730 * Perform a dquot buffer recovery.
2731 * Simple algorithm: if we have found a QUOTAOFF log item of the same type
2732 * (ie. USR or GRP), then just toss this buffer away; don't recover it.
2733 * Else, treat it as a regular buffer and do recovery.
2734 *
2735 * Return false if the buffer was tossed and true if we recovered the buffer to
2736 * indicate to the caller if the buffer needs writing.
2737 */
2738STATIC bool
2739xlog_recover_do_dquot_buffer(
2740 struct xfs_mount *mp,
2741 struct xlog *log,
2742 struct xlog_recover_item *item,
2743 struct xfs_buf *bp,
2744 struct xfs_buf_log_format *buf_f)
2745{
2746 uint type;
2747
2748 trace_xfs_log_recover_buf_dquot_buf(log, buf_f);
2749
2750 /*
2751 * Filesystems are required to send in quota flags at mount time.
2752 */
2753 if (!mp->m_qflags)
2754 return false;
2755
2756 type = 0;
2757 if (buf_f->blf_flags & XFS_BLF_UDQUOT_BUF)
2758 type |= XFS_DQ_USER;
2759 if (buf_f->blf_flags & XFS_BLF_PDQUOT_BUF)
2760 type |= XFS_DQ_PROJ;
2761 if (buf_f->blf_flags & XFS_BLF_GDQUOT_BUF)
2762 type |= XFS_DQ_GROUP;
2763 /*
2764 * This type of quotas was turned off, so ignore this buffer
2765 */
2766 if (log->l_quotaoffs_flag & type)
2767 return false;
2768
2769 xlog_recover_do_reg_buffer(mp, item, bp, buf_f, NULLCOMMITLSN);
2770 return true;
2771}
2772
2773/*
2774 * This routine replays a modification made to a buffer at runtime.
2775 * There are actually two types of buffer, regular and inode, which
2776 * are handled differently. Inode buffers are handled differently
2777 * in that we only recover a specific set of data from them, namely
2778 * the inode di_next_unlinked fields. This is because all other inode
2779 * data is actually logged via inode records and any data we replay
2780 * here which overlaps that may be stale.
2781 *
2782 * When meta-data buffers are freed at run time we log a buffer item
2783 * with the XFS_BLF_CANCEL bit set to indicate that previous copies
2784 * of the buffer in the log should not be replayed at recovery time.
2785 * This is so that if the blocks covered by the buffer are reused for
2786 * file data before we crash we don't end up replaying old, freed
2787 * meta-data into a user's file.
2788 *
2789 * To handle the cancellation of buffer log items, we make two passes
2790 * over the log during recovery. During the first we build a table of
2791 * those buffers which have been cancelled, and during the second we
2792 * only replay those buffers which do not have corresponding cancel
2793 * records in the table. See xlog_recover_buffer_pass[1,2] above
2794 * for more details on the implementation of the table of cancel records.
2795 */
2796STATIC int
2797xlog_recover_buffer_pass2(
2798 struct xlog *log,
2799 struct list_head *buffer_list,
2800 struct xlog_recover_item *item,
2801 xfs_lsn_t current_lsn)
2802{
2803 xfs_buf_log_format_t *buf_f = item->ri_buf[0].i_addr;
2804 xfs_mount_t *mp = log->l_mp;
2805 xfs_buf_t *bp;
2806 int error;
2807 uint buf_flags;
2808 xfs_lsn_t lsn;
2809
2810 /*
2811 * In this pass we only want to recover all the buffers which have
2812 * not been cancelled and are not cancellation buffers themselves.
2813 */
2814 if (xlog_check_buffer_cancelled(log, buf_f->blf_blkno,
2815 buf_f->blf_len, buf_f->blf_flags)) {
2816 trace_xfs_log_recover_buf_cancel(log, buf_f);
2817 return 0;
2818 }
2819
2820 trace_xfs_log_recover_buf_recover(log, buf_f);
2821
2822 buf_flags = 0;
2823 if (buf_f->blf_flags & XFS_BLF_INODE_BUF)
2824 buf_flags |= XBF_UNMAPPED;
2825
2826 bp = xfs_buf_read(mp->m_ddev_targp, buf_f->blf_blkno, buf_f->blf_len,
2827 buf_flags, NULL);
2828 if (!bp)
2829 return -ENOMEM;
2830 error = bp->b_error;
2831 if (error) {
2832 xfs_buf_ioerror_alert(bp, "xlog_recover_do..(read#1)");
2833 goto out_release;
2834 }
2835
2836 /*
2837 * Recover the buffer only if we get an LSN from it and it's less than
2838 * the lsn of the transaction we are replaying.
2839 *
2840 * Note that we have to be extremely careful of readahead here.
2841 * Readahead does not attach verfiers to the buffers so if we don't
2842 * actually do any replay after readahead because of the LSN we found
2843 * in the buffer if more recent than that current transaction then we
2844 * need to attach the verifier directly. Failure to do so can lead to
2845 * future recovery actions (e.g. EFI and unlinked list recovery) can
2846 * operate on the buffers and they won't get the verifier attached. This
2847 * can lead to blocks on disk having the correct content but a stale
2848 * CRC.
2849 *
2850 * It is safe to assume these clean buffers are currently up to date.
2851 * If the buffer is dirtied by a later transaction being replayed, then
2852 * the verifier will be reset to match whatever recover turns that
2853 * buffer into.
2854 */
2855 lsn = xlog_recover_get_buf_lsn(mp, bp);
2856 if (lsn && lsn != -1 && XFS_LSN_CMP(lsn, current_lsn) >= 0) {
2857 trace_xfs_log_recover_buf_skip(log, buf_f);
2858 xlog_recover_validate_buf_type(mp, bp, buf_f, NULLCOMMITLSN);
2859 goto out_release;
2860 }
2861
2862 if (buf_f->blf_flags & XFS_BLF_INODE_BUF) {
2863 error = xlog_recover_do_inode_buffer(mp, item, bp, buf_f);
2864 if (error)
2865 goto out_release;
2866 } else if (buf_f->blf_flags &
2867 (XFS_BLF_UDQUOT_BUF|XFS_BLF_PDQUOT_BUF|XFS_BLF_GDQUOT_BUF)) {
2868 bool dirty;
2869
2870 dirty = xlog_recover_do_dquot_buffer(mp, log, item, bp, buf_f);
2871 if (!dirty)
2872 goto out_release;
2873 } else {
2874 xlog_recover_do_reg_buffer(mp, item, bp, buf_f, current_lsn);
2875 }
2876
2877 /*
2878 * Perform delayed write on the buffer. Asynchronous writes will be
2879 * slower when taking into account all the buffers to be flushed.
2880 *
2881 * Also make sure that only inode buffers with good sizes stay in
2882 * the buffer cache. The kernel moves inodes in buffers of 1 block
2883 * or mp->m_inode_cluster_size bytes, whichever is bigger. The inode
2884 * buffers in the log can be a different size if the log was generated
2885 * by an older kernel using unclustered inode buffers or a newer kernel
2886 * running with a different inode cluster size. Regardless, if the
2887 * the inode buffer size isn't MAX(blocksize, mp->m_inode_cluster_size)
2888 * for *our* value of mp->m_inode_cluster_size, then we need to keep
2889 * the buffer out of the buffer cache so that the buffer won't
2890 * overlap with future reads of those inodes.
2891 */
2892 if (XFS_DINODE_MAGIC ==
2893 be16_to_cpu(*((__be16 *)xfs_buf_offset(bp, 0))) &&
2894 (BBTOB(bp->b_io_length) != MAX(log->l_mp->m_sb.sb_blocksize,
2895 (uint32_t)log->l_mp->m_inode_cluster_size))) {
2896 xfs_buf_stale(bp);
2897 error = xfs_bwrite(bp);
2898 } else {
2899 ASSERT(bp->b_target->bt_mount == mp);
2900 bp->b_iodone = xlog_recover_iodone;
2901 xfs_buf_delwri_queue(bp, buffer_list);
2902 }
2903
2904out_release:
2905 xfs_buf_relse(bp);
2906 return error;
2907}
2908
2909/*
2910 * Inode fork owner changes
2911 *
2912 * If we have been told that we have to reparent the inode fork, it's because an
2913 * extent swap operation on a CRC enabled filesystem has been done and we are
2914 * replaying it. We need to walk the BMBT of the appropriate fork and change the
2915 * owners of it.
2916 *
2917 * The complexity here is that we don't have an inode context to work with, so
2918 * after we've replayed the inode we need to instantiate one. This is where the
2919 * fun begins.
2920 *
2921 * We are in the middle of log recovery, so we can't run transactions. That
2922 * means we cannot use cache coherent inode instantiation via xfs_iget(), as
2923 * that will result in the corresponding iput() running the inode through
2924 * xfs_inactive(). If we've just replayed an inode core that changes the link
2925 * count to zero (i.e. it's been unlinked), then xfs_inactive() will run
2926 * transactions (bad!).
2927 *
2928 * So, to avoid this, we instantiate an inode directly from the inode core we've
2929 * just recovered. We have the buffer still locked, and all we really need to
2930 * instantiate is the inode core and the forks being modified. We can do this
2931 * manually, then run the inode btree owner change, and then tear down the
2932 * xfs_inode without having to run any transactions at all.
2933 *
2934 * Also, because we don't have a transaction context available here but need to
2935 * gather all the buffers we modify for writeback so we pass the buffer_list
2936 * instead for the operation to use.
2937 */
2938
2939STATIC int
2940xfs_recover_inode_owner_change(
2941 struct xfs_mount *mp,
2942 struct xfs_dinode *dip,
2943 struct xfs_inode_log_format *in_f,
2944 struct list_head *buffer_list)
2945{
2946 struct xfs_inode *ip;
2947 int error;
2948
2949 ASSERT(in_f->ilf_fields & (XFS_ILOG_DOWNER|XFS_ILOG_AOWNER));
2950
2951 ip = xfs_inode_alloc(mp, in_f->ilf_ino);
2952 if (!ip)
2953 return -ENOMEM;
2954
2955 /* instantiate the inode */
2956 xfs_inode_from_disk(ip, dip);
2957 ASSERT(ip->i_d.di_version >= 3);
2958
2959 error = xfs_iformat_fork(ip, dip);
2960 if (error)
2961 goto out_free_ip;
2962
2963 if (!xfs_inode_verify_forks(ip)) {
2964 error = -EFSCORRUPTED;
2965 goto out_free_ip;
2966 }
2967
2968 if (in_f->ilf_fields & XFS_ILOG_DOWNER) {
2969 ASSERT(in_f->ilf_fields & XFS_ILOG_DBROOT);
2970 error = xfs_bmbt_change_owner(NULL, ip, XFS_DATA_FORK,
2971 ip->i_ino, buffer_list);
2972 if (error)
2973 goto out_free_ip;
2974 }
2975
2976 if (in_f->ilf_fields & XFS_ILOG_AOWNER) {
2977 ASSERT(in_f->ilf_fields & XFS_ILOG_ABROOT);
2978 error = xfs_bmbt_change_owner(NULL, ip, XFS_ATTR_FORK,
2979 ip->i_ino, buffer_list);
2980 if (error)
2981 goto out_free_ip;
2982 }
2983
2984out_free_ip:
2985 xfs_inode_free(ip);
2986 return error;
2987}
2988
2989STATIC int
2990xlog_recover_inode_pass2(
2991 struct xlog *log,
2992 struct list_head *buffer_list,
2993 struct xlog_recover_item *item,
2994 xfs_lsn_t current_lsn)
2995{
2996 struct xfs_inode_log_format *in_f;
2997 xfs_mount_t *mp = log->l_mp;
2998 xfs_buf_t *bp;
2999 xfs_dinode_t *dip;
3000 int len;
3001 char *src;
3002 char *dest;
3003 int error;
3004 int attr_index;
3005 uint fields;
3006 struct xfs_log_dinode *ldip;
3007 uint isize;
3008 int need_free = 0;
3009
3010 if (item->ri_buf[0].i_len == sizeof(struct xfs_inode_log_format)) {
3011 in_f = item->ri_buf[0].i_addr;
3012 } else {
3013 in_f = kmem_alloc(sizeof(struct xfs_inode_log_format), KM_SLEEP);
3014 need_free = 1;
3015 error = xfs_inode_item_format_convert(&item->ri_buf[0], in_f);
3016 if (error)
3017 goto error;
3018 }
3019
3020 /*
3021 * Inode buffers can be freed, look out for it,
3022 * and do not replay the inode.
3023 */
3024 if (xlog_check_buffer_cancelled(log, in_f->ilf_blkno,
3025 in_f->ilf_len, 0)) {
3026 error = 0;
3027 trace_xfs_log_recover_inode_cancel(log, in_f);
3028 goto error;
3029 }
3030 trace_xfs_log_recover_inode_recover(log, in_f);
3031
3032 bp = xfs_buf_read(mp->m_ddev_targp, in_f->ilf_blkno, in_f->ilf_len, 0,
3033 &xfs_inode_buf_ops);
3034 if (!bp) {
3035 error = -ENOMEM;
3036 goto error;
3037 }
3038 error = bp->b_error;
3039 if (error) {
3040 xfs_buf_ioerror_alert(bp, "xlog_recover_do..(read#2)");
3041 goto out_release;
3042 }
3043 ASSERT(in_f->ilf_fields & XFS_ILOG_CORE);
3044 dip = xfs_buf_offset(bp, in_f->ilf_boffset);
3045
3046 /*
3047 * Make sure the place we're flushing out to really looks
3048 * like an inode!
3049 */
3050 if (unlikely(dip->di_magic != cpu_to_be16(XFS_DINODE_MAGIC))) {
3051 xfs_alert(mp,
3052 "%s: Bad inode magic number, dip = "PTR_FMT", dino bp = "PTR_FMT", ino = %Ld",
3053 __func__, dip, bp, in_f->ilf_ino);
3054 XFS_ERROR_REPORT("xlog_recover_inode_pass2(1)",
3055 XFS_ERRLEVEL_LOW, mp);
3056 error = -EFSCORRUPTED;
3057 goto out_release;
3058 }
3059 ldip = item->ri_buf[1].i_addr;
3060 if (unlikely(ldip->di_magic != XFS_DINODE_MAGIC)) {
3061 xfs_alert(mp,
3062 "%s: Bad inode log record, rec ptr "PTR_FMT", ino %Ld",
3063 __func__, item, in_f->ilf_ino);
3064 XFS_ERROR_REPORT("xlog_recover_inode_pass2(2)",
3065 XFS_ERRLEVEL_LOW, mp);
3066 error = -EFSCORRUPTED;
3067 goto out_release;
3068 }
3069
3070 /*
3071 * If the inode has an LSN in it, recover the inode only if it's less
3072 * than the lsn of the transaction we are replaying. Note: we still
3073 * need to replay an owner change even though the inode is more recent
3074 * than the transaction as there is no guarantee that all the btree
3075 * blocks are more recent than this transaction, too.
3076 */
3077 if (dip->di_version >= 3) {
3078 xfs_lsn_t lsn = be64_to_cpu(dip->di_lsn);
3079
3080 if (lsn && lsn != -1 && XFS_LSN_CMP(lsn, current_lsn) >= 0) {
3081 trace_xfs_log_recover_inode_skip(log, in_f);
3082 error = 0;
3083 goto out_owner_change;
3084 }
3085 }
3086
3087 /*
3088 * di_flushiter is only valid for v1/2 inodes. All changes for v3 inodes
3089 * are transactional and if ordering is necessary we can determine that
3090 * more accurately by the LSN field in the V3 inode core. Don't trust
3091 * the inode versions we might be changing them here - use the
3092 * superblock flag to determine whether we need to look at di_flushiter
3093 * to skip replay when the on disk inode is newer than the log one
3094 */
3095 if (!xfs_sb_version_hascrc(&mp->m_sb) &&
3096 ldip->di_flushiter < be16_to_cpu(dip->di_flushiter)) {
3097 /*
3098 * Deal with the wrap case, DI_MAX_FLUSH is less
3099 * than smaller numbers
3100 */
3101 if (be16_to_cpu(dip->di_flushiter) == DI_MAX_FLUSH &&
3102 ldip->di_flushiter < (DI_MAX_FLUSH >> 1)) {
3103 /* do nothing */
3104 } else {
3105 trace_xfs_log_recover_inode_skip(log, in_f);
3106 error = 0;
3107 goto out_release;
3108 }
3109 }
3110
3111 /* Take the opportunity to reset the flush iteration count */
3112 ldip->di_flushiter = 0;
3113
3114 if (unlikely(S_ISREG(ldip->di_mode))) {
3115 if ((ldip->di_format != XFS_DINODE_FMT_EXTENTS) &&
3116 (ldip->di_format != XFS_DINODE_FMT_BTREE)) {
3117 XFS_CORRUPTION_ERROR("xlog_recover_inode_pass2(3)",
3118 XFS_ERRLEVEL_LOW, mp, ldip);
3119 xfs_alert(mp,
3120 "%s: Bad regular inode log record, rec ptr "PTR_FMT", "
3121 "ino ptr = "PTR_FMT", ino bp = "PTR_FMT", ino %Ld",
3122 __func__, item, dip, bp, in_f->ilf_ino);
3123 error = -EFSCORRUPTED;
3124 goto out_release;
3125 }
3126 } else if (unlikely(S_ISDIR(ldip->di_mode))) {
3127 if ((ldip->di_format != XFS_DINODE_FMT_EXTENTS) &&
3128 (ldip->di_format != XFS_DINODE_FMT_BTREE) &&
3129 (ldip->di_format != XFS_DINODE_FMT_LOCAL)) {
3130 XFS_CORRUPTION_ERROR("xlog_recover_inode_pass2(4)",
3131 XFS_ERRLEVEL_LOW, mp, ldip);
3132 xfs_alert(mp,
3133 "%s: Bad dir inode log record, rec ptr "PTR_FMT", "
3134 "ino ptr = "PTR_FMT", ino bp = "PTR_FMT", ino %Ld",
3135 __func__, item, dip, bp, in_f->ilf_ino);
3136 error = -EFSCORRUPTED;
3137 goto out_release;
3138 }
3139 }
3140 if (unlikely(ldip->di_nextents + ldip->di_anextents > ldip->di_nblocks)){
3141 XFS_CORRUPTION_ERROR("xlog_recover_inode_pass2(5)",
3142 XFS_ERRLEVEL_LOW, mp, ldip);
3143 xfs_alert(mp,
3144 "%s: Bad inode log record, rec ptr "PTR_FMT", dino ptr "PTR_FMT", "
3145 "dino bp "PTR_FMT", ino %Ld, total extents = %d, nblocks = %Ld",
3146 __func__, item, dip, bp, in_f->ilf_ino,
3147 ldip->di_nextents + ldip->di_anextents,
3148 ldip->di_nblocks);
3149 error = -EFSCORRUPTED;
3150 goto out_release;
3151 }
3152 if (unlikely(ldip->di_forkoff > mp->m_sb.sb_inodesize)) {
3153 XFS_CORRUPTION_ERROR("xlog_recover_inode_pass2(6)",
3154 XFS_ERRLEVEL_LOW, mp, ldip);
3155 xfs_alert(mp,
3156 "%s: Bad inode log record, rec ptr "PTR_FMT", dino ptr "PTR_FMT", "
3157 "dino bp "PTR_FMT", ino %Ld, forkoff 0x%x", __func__,
3158 item, dip, bp, in_f->ilf_ino, ldip->di_forkoff);
3159 error = -EFSCORRUPTED;
3160 goto out_release;
3161 }
3162 isize = xfs_log_dinode_size(ldip->di_version);
3163 if (unlikely(item->ri_buf[1].i_len > isize)) {
3164 XFS_CORRUPTION_ERROR("xlog_recover_inode_pass2(7)",
3165 XFS_ERRLEVEL_LOW, mp, ldip);
3166 xfs_alert(mp,
3167 "%s: Bad inode log record length %d, rec ptr "PTR_FMT,
3168 __func__, item->ri_buf[1].i_len, item);
3169 error = -EFSCORRUPTED;
3170 goto out_release;
3171 }
3172
3173 /* recover the log dinode inode into the on disk inode */
3174 xfs_log_dinode_to_disk(ldip, dip);
3175
3176 fields = in_f->ilf_fields;
3177 if (fields & XFS_ILOG_DEV)
3178 xfs_dinode_put_rdev(dip, in_f->ilf_u.ilfu_rdev);
3179
3180 if (in_f->ilf_size == 2)
3181 goto out_owner_change;
3182 len = item->ri_buf[2].i_len;
3183 src = item->ri_buf[2].i_addr;
3184 ASSERT(in_f->ilf_size <= 4);
3185 ASSERT((in_f->ilf_size == 3) || (fields & XFS_ILOG_AFORK));
3186 ASSERT(!(fields & XFS_ILOG_DFORK) ||
3187 (len == in_f->ilf_dsize));
3188
3189 switch (fields & XFS_ILOG_DFORK) {
3190 case XFS_ILOG_DDATA:
3191 case XFS_ILOG_DEXT:
3192 memcpy(XFS_DFORK_DPTR(dip), src, len);
3193 break;
3194
3195 case XFS_ILOG_DBROOT:
3196 xfs_bmbt_to_bmdr(mp, (struct xfs_btree_block *)src, len,
3197 (xfs_bmdr_block_t *)XFS_DFORK_DPTR(dip),
3198 XFS_DFORK_DSIZE(dip, mp));
3199 break;
3200
3201 default:
3202 /*
3203 * There are no data fork flags set.
3204 */
3205 ASSERT((fields & XFS_ILOG_DFORK) == 0);
3206 break;
3207 }
3208
3209 /*
3210 * If we logged any attribute data, recover it. There may or
3211 * may not have been any other non-core data logged in this
3212 * transaction.
3213 */
3214 if (in_f->ilf_fields & XFS_ILOG_AFORK) {
3215 if (in_f->ilf_fields & XFS_ILOG_DFORK) {
3216 attr_index = 3;
3217 } else {
3218 attr_index = 2;
3219 }
3220 len = item->ri_buf[attr_index].i_len;
3221 src = item->ri_buf[attr_index].i_addr;
3222 ASSERT(len == in_f->ilf_asize);
3223
3224 switch (in_f->ilf_fields & XFS_ILOG_AFORK) {
3225 case XFS_ILOG_ADATA:
3226 case XFS_ILOG_AEXT:
3227 dest = XFS_DFORK_APTR(dip);
3228 ASSERT(len <= XFS_DFORK_ASIZE(dip, mp));
3229 memcpy(dest, src, len);
3230 break;
3231
3232 case XFS_ILOG_ABROOT:
3233 dest = XFS_DFORK_APTR(dip);
3234 xfs_bmbt_to_bmdr(mp, (struct xfs_btree_block *)src,
3235 len, (xfs_bmdr_block_t*)dest,
3236 XFS_DFORK_ASIZE(dip, mp));
3237 break;
3238
3239 default:
3240 xfs_warn(log->l_mp, "%s: Invalid flag", __func__);
3241 ASSERT(0);
3242 error = -EIO;
3243 goto out_release;
3244 }
3245 }
3246
3247out_owner_change:
3248 /* Recover the swapext owner change unless inode has been deleted */
3249 if ((in_f->ilf_fields & (XFS_ILOG_DOWNER|XFS_ILOG_AOWNER)) &&
3250 (dip->di_mode != 0))
3251 error = xfs_recover_inode_owner_change(mp, dip, in_f,
3252 buffer_list);
3253 /* re-generate the checksum. */
3254 xfs_dinode_calc_crc(log->l_mp, dip);
3255
3256 ASSERT(bp->b_target->bt_mount == mp);
3257 bp->b_iodone = xlog_recover_iodone;
3258 xfs_buf_delwri_queue(bp, buffer_list);
3259
3260out_release:
3261 xfs_buf_relse(bp);
3262error:
3263 if (need_free)
3264 kmem_free(in_f);
3265 return error;
3266}
3267
3268/*
3269 * Recover QUOTAOFF records. We simply make a note of it in the xlog
3270 * structure, so that we know not to do any dquot item or dquot buffer recovery,
3271 * of that type.
3272 */
3273STATIC int
3274xlog_recover_quotaoff_pass1(
3275 struct xlog *log,
3276 struct xlog_recover_item *item)
3277{
3278 xfs_qoff_logformat_t *qoff_f = item->ri_buf[0].i_addr;
3279 ASSERT(qoff_f);
3280
3281 /*
3282 * The logitem format's flag tells us if this was user quotaoff,
3283 * group/project quotaoff or both.
3284 */
3285 if (qoff_f->qf_flags & XFS_UQUOTA_ACCT)
3286 log->l_quotaoffs_flag |= XFS_DQ_USER;
3287 if (qoff_f->qf_flags & XFS_PQUOTA_ACCT)
3288 log->l_quotaoffs_flag |= XFS_DQ_PROJ;
3289 if (qoff_f->qf_flags & XFS_GQUOTA_ACCT)
3290 log->l_quotaoffs_flag |= XFS_DQ_GROUP;
3291
3292 return 0;
3293}
3294
3295/*
3296 * Recover a dquot record
3297 */
3298STATIC int
3299xlog_recover_dquot_pass2(
3300 struct xlog *log,
3301 struct list_head *buffer_list,
3302 struct xlog_recover_item *item,
3303 xfs_lsn_t current_lsn)
3304{
3305 xfs_mount_t *mp = log->l_mp;
3306 xfs_buf_t *bp;
3307 struct xfs_disk_dquot *ddq, *recddq;
3308 xfs_failaddr_t fa;
3309 int error;
3310 xfs_dq_logformat_t *dq_f;
3311 uint type;
3312
3313
3314 /*
3315 * Filesystems are required to send in quota flags at mount time.
3316 */
3317 if (mp->m_qflags == 0)
3318 return 0;
3319
3320 recddq = item->ri_buf[1].i_addr;
3321 if (recddq == NULL) {
3322 xfs_alert(log->l_mp, "NULL dquot in %s.", __func__);
3323 return -EIO;
3324 }
3325 if (item->ri_buf[1].i_len < sizeof(xfs_disk_dquot_t)) {
3326 xfs_alert(log->l_mp, "dquot too small (%d) in %s.",
3327 item->ri_buf[1].i_len, __func__);
3328 return -EIO;
3329 }
3330
3331 /*
3332 * This type of quotas was turned off, so ignore this record.
3333 */
3334 type = recddq->d_flags & (XFS_DQ_USER | XFS_DQ_PROJ | XFS_DQ_GROUP);
3335 ASSERT(type);
3336 if (log->l_quotaoffs_flag & type)
3337 return 0;
3338
3339 /*
3340 * At this point we know that quota was _not_ turned off.
3341 * Since the mount flags are not indicating to us otherwise, this
3342 * must mean that quota is on, and the dquot needs to be replayed.
3343 * Remember that we may not have fully recovered the superblock yet,
3344 * so we can't do the usual trick of looking at the SB quota bits.
3345 *
3346 * The other possibility, of course, is that the quota subsystem was
3347 * removed since the last mount - ENOSYS.
3348 */
3349 dq_f = item->ri_buf[0].i_addr;
3350 ASSERT(dq_f);
3351 fa = xfs_dquot_verify(mp, recddq, dq_f->qlf_id, 0, 0);
3352 if (fa) {
3353 xfs_alert(mp, "corrupt dquot ID 0x%x in log at %pS",
3354 dq_f->qlf_id, fa);
3355 return -EIO;
3356 }
3357 ASSERT(dq_f->qlf_len == 1);
3358
3359 /*
3360 * At this point we are assuming that the dquots have been allocated
3361 * and hence the buffer has valid dquots stamped in it. It should,
3362 * therefore, pass verifier validation. If the dquot is bad, then the
3363 * we'll return an error here, so we don't need to specifically check
3364 * the dquot in the buffer after the verifier has run.
3365 */
3366 error = xfs_trans_read_buf(mp, NULL, mp->m_ddev_targp, dq_f->qlf_blkno,
3367 XFS_FSB_TO_BB(mp, dq_f->qlf_len), 0, &bp,
3368 &xfs_dquot_buf_ops);
3369 if (error)
3370 return error;
3371
3372 ASSERT(bp);
3373 ddq = xfs_buf_offset(bp, dq_f->qlf_boffset);
3374
3375 /*
3376 * If the dquot has an LSN in it, recover the dquot only if it's less
3377 * than the lsn of the transaction we are replaying.
3378 */
3379 if (xfs_sb_version_hascrc(&mp->m_sb)) {
3380 struct xfs_dqblk *dqb = (struct xfs_dqblk *)ddq;
3381 xfs_lsn_t lsn = be64_to_cpu(dqb->dd_lsn);
3382
3383 if (lsn && lsn != -1 && XFS_LSN_CMP(lsn, current_lsn) >= 0) {
3384 goto out_release;
3385 }
3386 }
3387
3388 memcpy(ddq, recddq, item->ri_buf[1].i_len);
3389 if (xfs_sb_version_hascrc(&mp->m_sb)) {
3390 xfs_update_cksum((char *)ddq, sizeof(struct xfs_dqblk),
3391 XFS_DQUOT_CRC_OFF);
3392 }
3393
3394 ASSERT(dq_f->qlf_size == 2);
3395 ASSERT(bp->b_target->bt_mount == mp);
3396 bp->b_iodone = xlog_recover_iodone;
3397 xfs_buf_delwri_queue(bp, buffer_list);
3398
3399out_release:
3400 xfs_buf_relse(bp);
3401 return 0;
3402}
3403
3404/*
3405 * This routine is called to create an in-core extent free intent
3406 * item from the efi format structure which was logged on disk.
3407 * It allocates an in-core efi, copies the extents from the format
3408 * structure into it, and adds the efi to the AIL with the given
3409 * LSN.
3410 */
3411STATIC int
3412xlog_recover_efi_pass2(
3413 struct xlog *log,
3414 struct xlog_recover_item *item,
3415 xfs_lsn_t lsn)
3416{
3417 int error;
3418 struct xfs_mount *mp = log->l_mp;
3419 struct xfs_efi_log_item *efip;
3420 struct xfs_efi_log_format *efi_formatp;
3421
3422 efi_formatp = item->ri_buf[0].i_addr;
3423
3424 efip = xfs_efi_init(mp, efi_formatp->efi_nextents);
3425 error = xfs_efi_copy_format(&item->ri_buf[0], &efip->efi_format);
3426 if (error) {
3427 xfs_efi_item_free(efip);
3428 return error;
3429 }
3430 atomic_set(&efip->efi_next_extent, efi_formatp->efi_nextents);
3431
3432 spin_lock(&log->l_ailp->ail_lock);
3433 /*
3434 * The EFI has two references. One for the EFD and one for EFI to ensure
3435 * it makes it into the AIL. Insert the EFI into the AIL directly and
3436 * drop the EFI reference. Note that xfs_trans_ail_update() drops the
3437 * AIL lock.
3438 */
3439 xfs_trans_ail_update(log->l_ailp, &efip->efi_item, lsn);
3440 xfs_efi_release(efip);
3441 return 0;
3442}
3443
3444
3445/*
3446 * This routine is called when an EFD format structure is found in a committed
3447 * transaction in the log. Its purpose is to cancel the corresponding EFI if it
3448 * was still in the log. To do this it searches the AIL for the EFI with an id
3449 * equal to that in the EFD format structure. If we find it we drop the EFD
3450 * reference, which removes the EFI from the AIL and frees it.
3451 */
3452STATIC int
3453xlog_recover_efd_pass2(
3454 struct xlog *log,
3455 struct xlog_recover_item *item)
3456{
3457 xfs_efd_log_format_t *efd_formatp;
3458 xfs_efi_log_item_t *efip = NULL;
3459 xfs_log_item_t *lip;
3460 uint64_t efi_id;
3461 struct xfs_ail_cursor cur;
3462 struct xfs_ail *ailp = log->l_ailp;
3463
3464 efd_formatp = item->ri_buf[0].i_addr;
3465 ASSERT((item->ri_buf[0].i_len == (sizeof(xfs_efd_log_format_32_t) +
3466 ((efd_formatp->efd_nextents - 1) * sizeof(xfs_extent_32_t)))) ||
3467 (item->ri_buf[0].i_len == (sizeof(xfs_efd_log_format_64_t) +
3468 ((efd_formatp->efd_nextents - 1) * sizeof(xfs_extent_64_t)))));
3469 efi_id = efd_formatp->efd_efi_id;
3470
3471 /*
3472 * Search for the EFI with the id in the EFD format structure in the
3473 * AIL.
3474 */
3475 spin_lock(&ailp->ail_lock);
3476 lip = xfs_trans_ail_cursor_first(ailp, &cur, 0);
3477 while (lip != NULL) {
3478 if (lip->li_type == XFS_LI_EFI) {
3479 efip = (xfs_efi_log_item_t *)lip;
3480 if (efip->efi_format.efi_id == efi_id) {
3481 /*
3482 * Drop the EFD reference to the EFI. This
3483 * removes the EFI from the AIL and frees it.
3484 */
3485 spin_unlock(&ailp->ail_lock);
3486 xfs_efi_release(efip);
3487 spin_lock(&ailp->ail_lock);
3488 break;
3489 }
3490 }
3491 lip = xfs_trans_ail_cursor_next(ailp, &cur);
3492 }
3493
3494 xfs_trans_ail_cursor_done(&cur);
3495 spin_unlock(&ailp->ail_lock);
3496
3497 return 0;
3498}
3499
3500/*
3501 * This routine is called to create an in-core extent rmap update
3502 * item from the rui format structure which was logged on disk.
3503 * It allocates an in-core rui, copies the extents from the format
3504 * structure into it, and adds the rui to the AIL with the given
3505 * LSN.
3506 */
3507STATIC int
3508xlog_recover_rui_pass2(
3509 struct xlog *log,
3510 struct xlog_recover_item *item,
3511 xfs_lsn_t lsn)
3512{
3513 int error;
3514 struct xfs_mount *mp = log->l_mp;
3515 struct xfs_rui_log_item *ruip;
3516 struct xfs_rui_log_format *rui_formatp;
3517
3518 rui_formatp = item->ri_buf[0].i_addr;
3519
3520 ruip = xfs_rui_init(mp, rui_formatp->rui_nextents);
3521 error = xfs_rui_copy_format(&item->ri_buf[0], &ruip->rui_format);
3522 if (error) {
3523 xfs_rui_item_free(ruip);
3524 return error;
3525 }
3526 atomic_set(&ruip->rui_next_extent, rui_formatp->rui_nextents);
3527
3528 spin_lock(&log->l_ailp->ail_lock);
3529 /*
3530 * The RUI has two references. One for the RUD and one for RUI to ensure
3531 * it makes it into the AIL. Insert the RUI into the AIL directly and
3532 * drop the RUI reference. Note that xfs_trans_ail_update() drops the
3533 * AIL lock.
3534 */
3535 xfs_trans_ail_update(log->l_ailp, &ruip->rui_item, lsn);
3536 xfs_rui_release(ruip);
3537 return 0;
3538}
3539
3540
3541/*
3542 * This routine is called when an RUD format structure is found in a committed
3543 * transaction in the log. Its purpose is to cancel the corresponding RUI if it
3544 * was still in the log. To do this it searches the AIL for the RUI with an id
3545 * equal to that in the RUD format structure. If we find it we drop the RUD
3546 * reference, which removes the RUI from the AIL and frees it.
3547 */
3548STATIC int
3549xlog_recover_rud_pass2(
3550 struct xlog *log,
3551 struct xlog_recover_item *item)
3552{
3553 struct xfs_rud_log_format *rud_formatp;
3554 struct xfs_rui_log_item *ruip = NULL;
3555 struct xfs_log_item *lip;
3556 uint64_t rui_id;
3557 struct xfs_ail_cursor cur;
3558 struct xfs_ail *ailp = log->l_ailp;
3559
3560 rud_formatp = item->ri_buf[0].i_addr;
3561 ASSERT(item->ri_buf[0].i_len == sizeof(struct xfs_rud_log_format));
3562 rui_id = rud_formatp->rud_rui_id;
3563
3564 /*
3565 * Search for the RUI with the id in the RUD format structure in the
3566 * AIL.
3567 */
3568 spin_lock(&ailp->ail_lock);
3569 lip = xfs_trans_ail_cursor_first(ailp, &cur, 0);
3570 while (lip != NULL) {
3571 if (lip->li_type == XFS_LI_RUI) {
3572 ruip = (struct xfs_rui_log_item *)lip;
3573 if (ruip->rui_format.rui_id == rui_id) {
3574 /*
3575 * Drop the RUD reference to the RUI. This
3576 * removes the RUI from the AIL and frees it.
3577 */
3578 spin_unlock(&ailp->ail_lock);
3579 xfs_rui_release(ruip);
3580 spin_lock(&ailp->ail_lock);
3581 break;
3582 }
3583 }
3584 lip = xfs_trans_ail_cursor_next(ailp, &cur);
3585 }
3586
3587 xfs_trans_ail_cursor_done(&cur);
3588 spin_unlock(&ailp->ail_lock);
3589
3590 return 0;
3591}
3592
3593/*
3594 * Copy an CUI format buffer from the given buf, and into the destination
3595 * CUI format structure. The CUI/CUD items were designed not to need any
3596 * special alignment handling.
3597 */
3598static int
3599xfs_cui_copy_format(
3600 struct xfs_log_iovec *buf,
3601 struct xfs_cui_log_format *dst_cui_fmt)
3602{
3603 struct xfs_cui_log_format *src_cui_fmt;
3604 uint len;
3605
3606 src_cui_fmt = buf->i_addr;
3607 len = xfs_cui_log_format_sizeof(src_cui_fmt->cui_nextents);
3608
3609 if (buf->i_len == len) {
3610 memcpy(dst_cui_fmt, src_cui_fmt, len);
3611 return 0;
3612 }
3613 return -EFSCORRUPTED;
3614}
3615
3616/*
3617 * This routine is called to create an in-core extent refcount update
3618 * item from the cui format structure which was logged on disk.
3619 * It allocates an in-core cui, copies the extents from the format
3620 * structure into it, and adds the cui to the AIL with the given
3621 * LSN.
3622 */
3623STATIC int
3624xlog_recover_cui_pass2(
3625 struct xlog *log,
3626 struct xlog_recover_item *item,
3627 xfs_lsn_t lsn)
3628{
3629 int error;
3630 struct xfs_mount *mp = log->l_mp;
3631 struct xfs_cui_log_item *cuip;
3632 struct xfs_cui_log_format *cui_formatp;
3633
3634 cui_formatp = item->ri_buf[0].i_addr;
3635
3636 cuip = xfs_cui_init(mp, cui_formatp->cui_nextents);
3637 error = xfs_cui_copy_format(&item->ri_buf[0], &cuip->cui_format);
3638 if (error) {
3639 xfs_cui_item_free(cuip);
3640 return error;
3641 }
3642 atomic_set(&cuip->cui_next_extent, cui_formatp->cui_nextents);
3643
3644 spin_lock(&log->l_ailp->ail_lock);
3645 /*
3646 * The CUI has two references. One for the CUD and one for CUI to ensure
3647 * it makes it into the AIL. Insert the CUI into the AIL directly and
3648 * drop the CUI reference. Note that xfs_trans_ail_update() drops the
3649 * AIL lock.
3650 */
3651 xfs_trans_ail_update(log->l_ailp, &cuip->cui_item, lsn);
3652 xfs_cui_release(cuip);
3653 return 0;
3654}
3655
3656
3657/*
3658 * This routine is called when an CUD format structure is found in a committed
3659 * transaction in the log. Its purpose is to cancel the corresponding CUI if it
3660 * was still in the log. To do this it searches the AIL for the CUI with an id
3661 * equal to that in the CUD format structure. If we find it we drop the CUD
3662 * reference, which removes the CUI from the AIL and frees it.
3663 */
3664STATIC int
3665xlog_recover_cud_pass2(
3666 struct xlog *log,
3667 struct xlog_recover_item *item)
3668{
3669 struct xfs_cud_log_format *cud_formatp;
3670 struct xfs_cui_log_item *cuip = NULL;
3671 struct xfs_log_item *lip;
3672 uint64_t cui_id;
3673 struct xfs_ail_cursor cur;
3674 struct xfs_ail *ailp = log->l_ailp;
3675
3676 cud_formatp = item->ri_buf[0].i_addr;
3677 if (item->ri_buf[0].i_len != sizeof(struct xfs_cud_log_format))
3678 return -EFSCORRUPTED;
3679 cui_id = cud_formatp->cud_cui_id;
3680
3681 /*
3682 * Search for the CUI with the id in the CUD format structure in the
3683 * AIL.
3684 */
3685 spin_lock(&ailp->ail_lock);
3686 lip = xfs_trans_ail_cursor_first(ailp, &cur, 0);
3687 while (lip != NULL) {
3688 if (lip->li_type == XFS_LI_CUI) {
3689 cuip = (struct xfs_cui_log_item *)lip;
3690 if (cuip->cui_format.cui_id == cui_id) {
3691 /*
3692 * Drop the CUD reference to the CUI. This
3693 * removes the CUI from the AIL and frees it.
3694 */
3695 spin_unlock(&ailp->ail_lock);
3696 xfs_cui_release(cuip);
3697 spin_lock(&ailp->ail_lock);
3698 break;
3699 }
3700 }
3701 lip = xfs_trans_ail_cursor_next(ailp, &cur);
3702 }
3703
3704 xfs_trans_ail_cursor_done(&cur);
3705 spin_unlock(&ailp->ail_lock);
3706
3707 return 0;
3708}
3709
3710/*
3711 * Copy an BUI format buffer from the given buf, and into the destination
3712 * BUI format structure. The BUI/BUD items were designed not to need any
3713 * special alignment handling.
3714 */
3715static int
3716xfs_bui_copy_format(
3717 struct xfs_log_iovec *buf,
3718 struct xfs_bui_log_format *dst_bui_fmt)
3719{
3720 struct xfs_bui_log_format *src_bui_fmt;
3721 uint len;
3722
3723 src_bui_fmt = buf->i_addr;
3724 len = xfs_bui_log_format_sizeof(src_bui_fmt->bui_nextents);
3725
3726 if (buf->i_len == len) {
3727 memcpy(dst_bui_fmt, src_bui_fmt, len);
3728 return 0;
3729 }
3730 return -EFSCORRUPTED;
3731}
3732
3733/*
3734 * This routine is called to create an in-core extent bmap update
3735 * item from the bui format structure which was logged on disk.
3736 * It allocates an in-core bui, copies the extents from the format
3737 * structure into it, and adds the bui to the AIL with the given
3738 * LSN.
3739 */
3740STATIC int
3741xlog_recover_bui_pass2(
3742 struct xlog *log,
3743 struct xlog_recover_item *item,
3744 xfs_lsn_t lsn)
3745{
3746 int error;
3747 struct xfs_mount *mp = log->l_mp;
3748 struct xfs_bui_log_item *buip;
3749 struct xfs_bui_log_format *bui_formatp;
3750
3751 bui_formatp = item->ri_buf[0].i_addr;
3752
3753 if (bui_formatp->bui_nextents != XFS_BUI_MAX_FAST_EXTENTS)
3754 return -EFSCORRUPTED;
3755 buip = xfs_bui_init(mp);
3756 error = xfs_bui_copy_format(&item->ri_buf[0], &buip->bui_format);
3757 if (error) {
3758 xfs_bui_item_free(buip);
3759 return error;
3760 }
3761 atomic_set(&buip->bui_next_extent, bui_formatp->bui_nextents);
3762
3763 spin_lock(&log->l_ailp->ail_lock);
3764 /*
3765 * The RUI has two references. One for the RUD and one for RUI to ensure
3766 * it makes it into the AIL. Insert the RUI into the AIL directly and
3767 * drop the RUI reference. Note that xfs_trans_ail_update() drops the
3768 * AIL lock.
3769 */
3770 xfs_trans_ail_update(log->l_ailp, &buip->bui_item, lsn);
3771 xfs_bui_release(buip);
3772 return 0;
3773}
3774
3775
3776/*
3777 * This routine is called when an BUD format structure is found in a committed
3778 * transaction in the log. Its purpose is to cancel the corresponding BUI if it
3779 * was still in the log. To do this it searches the AIL for the BUI with an id
3780 * equal to that in the BUD format structure. If we find it we drop the BUD
3781 * reference, which removes the BUI from the AIL and frees it.
3782 */
3783STATIC int
3784xlog_recover_bud_pass2(
3785 struct xlog *log,
3786 struct xlog_recover_item *item)
3787{
3788 struct xfs_bud_log_format *bud_formatp;
3789 struct xfs_bui_log_item *buip = NULL;
3790 struct xfs_log_item *lip;
3791 uint64_t bui_id;
3792 struct xfs_ail_cursor cur;
3793 struct xfs_ail *ailp = log->l_ailp;
3794
3795 bud_formatp = item->ri_buf[0].i_addr;
3796 if (item->ri_buf[0].i_len != sizeof(struct xfs_bud_log_format))
3797 return -EFSCORRUPTED;
3798 bui_id = bud_formatp->bud_bui_id;
3799
3800 /*
3801 * Search for the BUI with the id in the BUD format structure in the
3802 * AIL.
3803 */
3804 spin_lock(&ailp->ail_lock);
3805 lip = xfs_trans_ail_cursor_first(ailp, &cur, 0);
3806 while (lip != NULL) {
3807 if (lip->li_type == XFS_LI_BUI) {
3808 buip = (struct xfs_bui_log_item *)lip;
3809 if (buip->bui_format.bui_id == bui_id) {
3810 /*
3811 * Drop the BUD reference to the BUI. This
3812 * removes the BUI from the AIL and frees it.
3813 */
3814 spin_unlock(&ailp->ail_lock);
3815 xfs_bui_release(buip);
3816 spin_lock(&ailp->ail_lock);
3817 break;
3818 }
3819 }
3820 lip = xfs_trans_ail_cursor_next(ailp, &cur);
3821 }
3822
3823 xfs_trans_ail_cursor_done(&cur);
3824 spin_unlock(&ailp->ail_lock);
3825
3826 return 0;
3827}
3828
3829/*
3830 * This routine is called when an inode create format structure is found in a
3831 * committed transaction in the log. It's purpose is to initialise the inodes
3832 * being allocated on disk. This requires us to get inode cluster buffers that
3833 * match the range to be initialised, stamped with inode templates and written
3834 * by delayed write so that subsequent modifications will hit the cached buffer
3835 * and only need writing out at the end of recovery.
3836 */
3837STATIC int
3838xlog_recover_do_icreate_pass2(
3839 struct xlog *log,
3840 struct list_head *buffer_list,
3841 xlog_recover_item_t *item)
3842{
3843 struct xfs_mount *mp = log->l_mp;
3844 struct xfs_icreate_log *icl;
3845 xfs_agnumber_t agno;
3846 xfs_agblock_t agbno;
3847 unsigned int count;
3848 unsigned int isize;
3849 xfs_agblock_t length;
3850 int blks_per_cluster;
3851 int bb_per_cluster;
3852 int cancel_count;
3853 int nbufs;
3854 int i;
3855
3856 icl = (struct xfs_icreate_log *)item->ri_buf[0].i_addr;
3857 if (icl->icl_type != XFS_LI_ICREATE) {
3858 xfs_warn(log->l_mp, "xlog_recover_do_icreate_trans: bad type");
3859 return -EINVAL;
3860 }
3861
3862 if (icl->icl_size != 1) {
3863 xfs_warn(log->l_mp, "xlog_recover_do_icreate_trans: bad icl size");
3864 return -EINVAL;
3865 }
3866
3867 agno = be32_to_cpu(icl->icl_ag);
3868 if (agno >= mp->m_sb.sb_agcount) {
3869 xfs_warn(log->l_mp, "xlog_recover_do_icreate_trans: bad agno");
3870 return -EINVAL;
3871 }
3872 agbno = be32_to_cpu(icl->icl_agbno);
3873 if (!agbno || agbno == NULLAGBLOCK || agbno >= mp->m_sb.sb_agblocks) {
3874 xfs_warn(log->l_mp, "xlog_recover_do_icreate_trans: bad agbno");
3875 return -EINVAL;
3876 }
3877 isize = be32_to_cpu(icl->icl_isize);
3878 if (isize != mp->m_sb.sb_inodesize) {
3879 xfs_warn(log->l_mp, "xlog_recover_do_icreate_trans: bad isize");
3880 return -EINVAL;
3881 }
3882 count = be32_to_cpu(icl->icl_count);
3883 if (!count) {
3884 xfs_warn(log->l_mp, "xlog_recover_do_icreate_trans: bad count");
3885 return -EINVAL;
3886 }
3887 length = be32_to_cpu(icl->icl_length);
3888 if (!length || length >= mp->m_sb.sb_agblocks) {
3889 xfs_warn(log->l_mp, "xlog_recover_do_icreate_trans: bad length");
3890 return -EINVAL;
3891 }
3892
3893 /*
3894 * The inode chunk is either full or sparse and we only support
3895 * m_ialloc_min_blks sized sparse allocations at this time.
3896 */
3897 if (length != mp->m_ialloc_blks &&
3898 length != mp->m_ialloc_min_blks) {
3899 xfs_warn(log->l_mp,
3900 "%s: unsupported chunk length", __FUNCTION__);
3901 return -EINVAL;
3902 }
3903
3904 /* verify inode count is consistent with extent length */
3905 if ((count >> mp->m_sb.sb_inopblog) != length) {
3906 xfs_warn(log->l_mp,
3907 "%s: inconsistent inode count and chunk length",
3908 __FUNCTION__);
3909 return -EINVAL;
3910 }
3911
3912 /*
3913 * The icreate transaction can cover multiple cluster buffers and these
3914 * buffers could have been freed and reused. Check the individual
3915 * buffers for cancellation so we don't overwrite anything written after
3916 * a cancellation.
3917 */
3918 blks_per_cluster = xfs_icluster_size_fsb(mp);
3919 bb_per_cluster = XFS_FSB_TO_BB(mp, blks_per_cluster);
3920 nbufs = length / blks_per_cluster;
3921 for (i = 0, cancel_count = 0; i < nbufs; i++) {
3922 xfs_daddr_t daddr;
3923
3924 daddr = XFS_AGB_TO_DADDR(mp, agno,
3925 agbno + i * blks_per_cluster);
3926 if (xlog_check_buffer_cancelled(log, daddr, bb_per_cluster, 0))
3927 cancel_count++;
3928 }
3929
3930 /*
3931 * We currently only use icreate for a single allocation at a time. This
3932 * means we should expect either all or none of the buffers to be
3933 * cancelled. Be conservative and skip replay if at least one buffer is
3934 * cancelled, but warn the user that something is awry if the buffers
3935 * are not consistent.
3936 *
3937 * XXX: This must be refined to only skip cancelled clusters once we use
3938 * icreate for multiple chunk allocations.
3939 */
3940 ASSERT(!cancel_count || cancel_count == nbufs);
3941 if (cancel_count) {
3942 if (cancel_count != nbufs)
3943 xfs_warn(mp,
3944 "WARNING: partial inode chunk cancellation, skipped icreate.");
3945 trace_xfs_log_recover_icreate_cancel(log, icl);
3946 return 0;
3947 }
3948
3949 trace_xfs_log_recover_icreate_recover(log, icl);
3950 return xfs_ialloc_inode_init(mp, NULL, buffer_list, count, agno, agbno,
3951 length, be32_to_cpu(icl->icl_gen));
3952}
3953
3954STATIC void
3955xlog_recover_buffer_ra_pass2(
3956 struct xlog *log,
3957 struct xlog_recover_item *item)
3958{
3959 struct xfs_buf_log_format *buf_f = item->ri_buf[0].i_addr;
3960 struct xfs_mount *mp = log->l_mp;
3961
3962 if (xlog_peek_buffer_cancelled(log, buf_f->blf_blkno,
3963 buf_f->blf_len, buf_f->blf_flags)) {
3964 return;
3965 }
3966
3967 xfs_buf_readahead(mp->m_ddev_targp, buf_f->blf_blkno,
3968 buf_f->blf_len, NULL);
3969}
3970
3971STATIC void
3972xlog_recover_inode_ra_pass2(
3973 struct xlog *log,
3974 struct xlog_recover_item *item)
3975{
3976 struct xfs_inode_log_format ilf_buf;
3977 struct xfs_inode_log_format *ilfp;
3978 struct xfs_mount *mp = log->l_mp;
3979 int error;
3980
3981 if (item->ri_buf[0].i_len == sizeof(struct xfs_inode_log_format)) {
3982 ilfp = item->ri_buf[0].i_addr;
3983 } else {
3984 ilfp = &ilf_buf;
3985 memset(ilfp, 0, sizeof(*ilfp));
3986 error = xfs_inode_item_format_convert(&item->ri_buf[0], ilfp);
3987 if (error)
3988 return;
3989 }
3990
3991 if (xlog_peek_buffer_cancelled(log, ilfp->ilf_blkno, ilfp->ilf_len, 0))
3992 return;
3993
3994 xfs_buf_readahead(mp->m_ddev_targp, ilfp->ilf_blkno,
3995 ilfp->ilf_len, &xfs_inode_buf_ra_ops);
3996}
3997
3998STATIC void
3999xlog_recover_dquot_ra_pass2(
4000 struct xlog *log,
4001 struct xlog_recover_item *item)
4002{
4003 struct xfs_mount *mp = log->l_mp;
4004 struct xfs_disk_dquot *recddq;
4005 struct xfs_dq_logformat *dq_f;
4006 uint type;
4007 int len;
4008
4009
4010 if (mp->m_qflags == 0)
4011 return;
4012
4013 recddq = item->ri_buf[1].i_addr;
4014 if (recddq == NULL)
4015 return;
4016 if (item->ri_buf[1].i_len < sizeof(struct xfs_disk_dquot))
4017 return;
4018
4019 type = recddq->d_flags & (XFS_DQ_USER | XFS_DQ_PROJ | XFS_DQ_GROUP);
4020 ASSERT(type);
4021 if (log->l_quotaoffs_flag & type)
4022 return;
4023
4024 dq_f = item->ri_buf[0].i_addr;
4025 ASSERT(dq_f);
4026 ASSERT(dq_f->qlf_len == 1);
4027
4028 len = XFS_FSB_TO_BB(mp, dq_f->qlf_len);
4029 if (xlog_peek_buffer_cancelled(log, dq_f->qlf_blkno, len, 0))
4030 return;
4031
4032 xfs_buf_readahead(mp->m_ddev_targp, dq_f->qlf_blkno, len,
4033 &xfs_dquot_buf_ra_ops);
4034}
4035
4036STATIC void
4037xlog_recover_ra_pass2(
4038 struct xlog *log,
4039 struct xlog_recover_item *item)
4040{
4041 switch (ITEM_TYPE(item)) {
4042 case XFS_LI_BUF:
4043 xlog_recover_buffer_ra_pass2(log, item);
4044 break;
4045 case XFS_LI_INODE:
4046 xlog_recover_inode_ra_pass2(log, item);
4047 break;
4048 case XFS_LI_DQUOT:
4049 xlog_recover_dquot_ra_pass2(log, item);
4050 break;
4051 case XFS_LI_EFI:
4052 case XFS_LI_EFD:
4053 case XFS_LI_QUOTAOFF:
4054 case XFS_LI_RUI:
4055 case XFS_LI_RUD:
4056 case XFS_LI_CUI:
4057 case XFS_LI_CUD:
4058 case XFS_LI_BUI:
4059 case XFS_LI_BUD:
4060 default:
4061 break;
4062 }
4063}
4064
4065STATIC int
4066xlog_recover_commit_pass1(
4067 struct xlog *log,
4068 struct xlog_recover *trans,
4069 struct xlog_recover_item *item)
4070{
4071 trace_xfs_log_recover_item_recover(log, trans, item, XLOG_RECOVER_PASS1);
4072
4073 switch (ITEM_TYPE(item)) {
4074 case XFS_LI_BUF:
4075 return xlog_recover_buffer_pass1(log, item);
4076 case XFS_LI_QUOTAOFF:
4077 return xlog_recover_quotaoff_pass1(log, item);
4078 case XFS_LI_INODE:
4079 case XFS_LI_EFI:
4080 case XFS_LI_EFD:
4081 case XFS_LI_DQUOT:
4082 case XFS_LI_ICREATE:
4083 case XFS_LI_RUI:
4084 case XFS_LI_RUD:
4085 case XFS_LI_CUI:
4086 case XFS_LI_CUD:
4087 case XFS_LI_BUI:
4088 case XFS_LI_BUD:
4089 /* nothing to do in pass 1 */
4090 return 0;
4091 default:
4092 xfs_warn(log->l_mp, "%s: invalid item type (%d)",
4093 __func__, ITEM_TYPE(item));
4094 ASSERT(0);
4095 return -EIO;
4096 }
4097}
4098
4099STATIC int
4100xlog_recover_commit_pass2(
4101 struct xlog *log,
4102 struct xlog_recover *trans,
4103 struct list_head *buffer_list,
4104 struct xlog_recover_item *item)
4105{
4106 trace_xfs_log_recover_item_recover(log, trans, item, XLOG_RECOVER_PASS2);
4107
4108 switch (ITEM_TYPE(item)) {
4109 case XFS_LI_BUF:
4110 return xlog_recover_buffer_pass2(log, buffer_list, item,
4111 trans->r_lsn);
4112 case XFS_LI_INODE:
4113 return xlog_recover_inode_pass2(log, buffer_list, item,
4114 trans->r_lsn);
4115 case XFS_LI_EFI:
4116 return xlog_recover_efi_pass2(log, item, trans->r_lsn);
4117 case XFS_LI_EFD:
4118 return xlog_recover_efd_pass2(log, item);
4119 case XFS_LI_RUI:
4120 return xlog_recover_rui_pass2(log, item, trans->r_lsn);
4121 case XFS_LI_RUD:
4122 return xlog_recover_rud_pass2(log, item);
4123 case XFS_LI_CUI:
4124 return xlog_recover_cui_pass2(log, item, trans->r_lsn);
4125 case XFS_LI_CUD:
4126 return xlog_recover_cud_pass2(log, item);
4127 case XFS_LI_BUI:
4128 return xlog_recover_bui_pass2(log, item, trans->r_lsn);
4129 case XFS_LI_BUD:
4130 return xlog_recover_bud_pass2(log, item);
4131 case XFS_LI_DQUOT:
4132 return xlog_recover_dquot_pass2(log, buffer_list, item,
4133 trans->r_lsn);
4134 case XFS_LI_ICREATE:
4135 return xlog_recover_do_icreate_pass2(log, buffer_list, item);
4136 case XFS_LI_QUOTAOFF:
4137 /* nothing to do in pass2 */
4138 return 0;
4139 default:
4140 xfs_warn(log->l_mp, "%s: invalid item type (%d)",
4141 __func__, ITEM_TYPE(item));
4142 ASSERT(0);
4143 return -EIO;
4144 }
4145}
4146
4147STATIC int
4148xlog_recover_items_pass2(
4149 struct xlog *log,
4150 struct xlog_recover *trans,
4151 struct list_head *buffer_list,
4152 struct list_head *item_list)
4153{
4154 struct xlog_recover_item *item;
4155 int error = 0;
4156
4157 list_for_each_entry(item, item_list, ri_list) {
4158 error = xlog_recover_commit_pass2(log, trans,
4159 buffer_list, item);
4160 if (error)
4161 return error;
4162 }
4163
4164 return error;
4165}
4166
4167/*
4168 * Perform the transaction.
4169 *
4170 * If the transaction modifies a buffer or inode, do it now. Otherwise,
4171 * EFIs and EFDs get queued up by adding entries into the AIL for them.
4172 */
4173STATIC int
4174xlog_recover_commit_trans(
4175 struct xlog *log,
4176 struct xlog_recover *trans,
4177 int pass,
4178 struct list_head *buffer_list)
4179{
4180 int error = 0;
4181 int items_queued = 0;
4182 struct xlog_recover_item *item;
4183 struct xlog_recover_item *next;
4184 LIST_HEAD (ra_list);
4185 LIST_HEAD (done_list);
4186
4187 #define XLOG_RECOVER_COMMIT_QUEUE_MAX 100
4188
4189 hlist_del_init(&trans->r_list);
4190
4191 error = xlog_recover_reorder_trans(log, trans, pass);
4192 if (error)
4193 return error;
4194
4195 list_for_each_entry_safe(item, next, &trans->r_itemq, ri_list) {
4196 switch (pass) {
4197 case XLOG_RECOVER_PASS1:
4198 error = xlog_recover_commit_pass1(log, trans, item);
4199 break;
4200 case XLOG_RECOVER_PASS2:
4201 xlog_recover_ra_pass2(log, item);
4202 list_move_tail(&item->ri_list, &ra_list);
4203 items_queued++;
4204 if (items_queued >= XLOG_RECOVER_COMMIT_QUEUE_MAX) {
4205 error = xlog_recover_items_pass2(log, trans,
4206 buffer_list, &ra_list);
4207 list_splice_tail_init(&ra_list, &done_list);
4208 items_queued = 0;
4209 }
4210
4211 break;
4212 default:
4213 ASSERT(0);
4214 }
4215
4216 if (error)
4217 goto out;
4218 }
4219
4220out:
4221 if (!list_empty(&ra_list)) {
4222 if (!error)
4223 error = xlog_recover_items_pass2(log, trans,
4224 buffer_list, &ra_list);
4225 list_splice_tail_init(&ra_list, &done_list);
4226 }
4227
4228 if (!list_empty(&done_list))
4229 list_splice_init(&done_list, &trans->r_itemq);
4230
4231 return error;
4232}
4233
4234STATIC void
4235xlog_recover_add_item(
4236 struct list_head *head)
4237{
4238 xlog_recover_item_t *item;
4239
4240 item = kmem_zalloc(sizeof(xlog_recover_item_t), KM_SLEEP);
4241 INIT_LIST_HEAD(&item->ri_list);
4242 list_add_tail(&item->ri_list, head);
4243}
4244
4245STATIC int
4246xlog_recover_add_to_cont_trans(
4247 struct xlog *log,
4248 struct xlog_recover *trans,
4249 char *dp,
4250 int len)
4251{
4252 xlog_recover_item_t *item;
4253 char *ptr, *old_ptr;
4254 int old_len;
4255
4256 /*
4257 * If the transaction is empty, the header was split across this and the
4258 * previous record. Copy the rest of the header.
4259 */
4260 if (list_empty(&trans->r_itemq)) {
4261 ASSERT(len <= sizeof(struct xfs_trans_header));
4262 if (len > sizeof(struct xfs_trans_header)) {
4263 xfs_warn(log->l_mp, "%s: bad header length", __func__);
4264 return -EIO;
4265 }
4266
4267 xlog_recover_add_item(&trans->r_itemq);
4268 ptr = (char *)&trans->r_theader +
4269 sizeof(struct xfs_trans_header) - len;
4270 memcpy(ptr, dp, len);
4271 return 0;
4272 }
4273
4274 /* take the tail entry */
4275 item = list_entry(trans->r_itemq.prev, xlog_recover_item_t, ri_list);
4276
4277 old_ptr = item->ri_buf[item->ri_cnt-1].i_addr;
4278 old_len = item->ri_buf[item->ri_cnt-1].i_len;
4279
4280 ptr = kmem_realloc(old_ptr, len + old_len, KM_SLEEP);
4281 memcpy(&ptr[old_len], dp, len);
4282 item->ri_buf[item->ri_cnt-1].i_len += len;
4283 item->ri_buf[item->ri_cnt-1].i_addr = ptr;
4284 trace_xfs_log_recover_item_add_cont(log, trans, item, 0);
4285 return 0;
4286}
4287
4288/*
4289 * The next region to add is the start of a new region. It could be
4290 * a whole region or it could be the first part of a new region. Because
4291 * of this, the assumption here is that the type and size fields of all
4292 * format structures fit into the first 32 bits of the structure.
4293 *
4294 * This works because all regions must be 32 bit aligned. Therefore, we
4295 * either have both fields or we have neither field. In the case we have
4296 * neither field, the data part of the region is zero length. We only have
4297 * a log_op_header and can throw away the header since a new one will appear
4298 * later. If we have at least 4 bytes, then we can determine how many regions
4299 * will appear in the current log item.
4300 */
4301STATIC int
4302xlog_recover_add_to_trans(
4303 struct xlog *log,
4304 struct xlog_recover *trans,
4305 char *dp,
4306 int len)
4307{
4308 struct xfs_inode_log_format *in_f; /* any will do */
4309 xlog_recover_item_t *item;
4310 char *ptr;
4311
4312 if (!len)
4313 return 0;
4314 if (list_empty(&trans->r_itemq)) {
4315 /* we need to catch log corruptions here */
4316 if (*(uint *)dp != XFS_TRANS_HEADER_MAGIC) {
4317 xfs_warn(log->l_mp, "%s: bad header magic number",
4318 __func__);
4319 ASSERT(0);
4320 return -EIO;
4321 }
4322
4323 if (len > sizeof(struct xfs_trans_header)) {
4324 xfs_warn(log->l_mp, "%s: bad header length", __func__);
4325 ASSERT(0);
4326 return -EIO;
4327 }
4328
4329 /*
4330 * The transaction header can be arbitrarily split across op
4331 * records. If we don't have the whole thing here, copy what we
4332 * do have and handle the rest in the next record.
4333 */
4334 if (len == sizeof(struct xfs_trans_header))
4335 xlog_recover_add_item(&trans->r_itemq);
4336 memcpy(&trans->r_theader, dp, len);
4337 return 0;
4338 }
4339
4340 ptr = kmem_alloc(len, KM_SLEEP);
4341 memcpy(ptr, dp, len);
4342 in_f = (struct xfs_inode_log_format *)ptr;
4343
4344 /* take the tail entry */
4345 item = list_entry(trans->r_itemq.prev, xlog_recover_item_t, ri_list);
4346 if (item->ri_total != 0 &&
4347 item->ri_total == item->ri_cnt) {
4348 /* tail item is in use, get a new one */
4349 xlog_recover_add_item(&trans->r_itemq);
4350 item = list_entry(trans->r_itemq.prev,
4351 xlog_recover_item_t, ri_list);
4352 }
4353
4354 if (item->ri_total == 0) { /* first region to be added */
4355 if (in_f->ilf_size == 0 ||
4356 in_f->ilf_size > XLOG_MAX_REGIONS_IN_ITEM) {
4357 xfs_warn(log->l_mp,
4358 "bad number of regions (%d) in inode log format",
4359 in_f->ilf_size);
4360 ASSERT(0);
4361 kmem_free(ptr);
4362 return -EIO;
4363 }
4364
4365 item->ri_total = in_f->ilf_size;
4366 item->ri_buf =
4367 kmem_zalloc(item->ri_total * sizeof(xfs_log_iovec_t),
4368 KM_SLEEP);
4369 }
4370 ASSERT(item->ri_total > item->ri_cnt);
4371 /* Description region is ri_buf[0] */
4372 item->ri_buf[item->ri_cnt].i_addr = ptr;
4373 item->ri_buf[item->ri_cnt].i_len = len;
4374 item->ri_cnt++;
4375 trace_xfs_log_recover_item_add(log, trans, item, 0);
4376 return 0;
4377}
4378
4379/*
4380 * Free up any resources allocated by the transaction
4381 *
4382 * Remember that EFIs, EFDs, and IUNLINKs are handled later.
4383 */
4384STATIC void
4385xlog_recover_free_trans(
4386 struct xlog_recover *trans)
4387{
4388 xlog_recover_item_t *item, *n;
4389 int i;
4390
4391 hlist_del_init(&trans->r_list);
4392
4393 list_for_each_entry_safe(item, n, &trans->r_itemq, ri_list) {
4394 /* Free the regions in the item. */
4395 list_del(&item->ri_list);
4396 for (i = 0; i < item->ri_cnt; i++)
4397 kmem_free(item->ri_buf[i].i_addr);
4398 /* Free the item itself */
4399 kmem_free(item->ri_buf);
4400 kmem_free(item);
4401 }
4402 /* Free the transaction recover structure */
4403 kmem_free(trans);
4404}
4405
4406/*
4407 * On error or completion, trans is freed.
4408 */
4409STATIC int
4410xlog_recovery_process_trans(
4411 struct xlog *log,
4412 struct xlog_recover *trans,
4413 char *dp,
4414 unsigned int len,
4415 unsigned int flags,
4416 int pass,
4417 struct list_head *buffer_list)
4418{
4419 int error = 0;
4420 bool freeit = false;
4421
4422 /* mask off ophdr transaction container flags */
4423 flags &= ~XLOG_END_TRANS;
4424 if (flags & XLOG_WAS_CONT_TRANS)
4425 flags &= ~XLOG_CONTINUE_TRANS;
4426
4427 /*
4428 * Callees must not free the trans structure. We'll decide if we need to
4429 * free it or not based on the operation being done and it's result.
4430 */
4431 switch (flags) {
4432 /* expected flag values */
4433 case 0:
4434 case XLOG_CONTINUE_TRANS:
4435 error = xlog_recover_add_to_trans(log, trans, dp, len);
4436 break;
4437 case XLOG_WAS_CONT_TRANS:
4438 error = xlog_recover_add_to_cont_trans(log, trans, dp, len);
4439 break;
4440 case XLOG_COMMIT_TRANS:
4441 error = xlog_recover_commit_trans(log, trans, pass,
4442 buffer_list);
4443 /* success or fail, we are now done with this transaction. */
4444 freeit = true;
4445 break;
4446
4447 /* unexpected flag values */
4448 case XLOG_UNMOUNT_TRANS:
4449 /* just skip trans */
4450 xfs_warn(log->l_mp, "%s: Unmount LR", __func__);
4451 freeit = true;
4452 break;
4453 case XLOG_START_TRANS:
4454 default:
4455 xfs_warn(log->l_mp, "%s: bad flag 0x%x", __func__, flags);
4456 ASSERT(0);
4457 error = -EIO;
4458 break;
4459 }
4460 if (error || freeit)
4461 xlog_recover_free_trans(trans);
4462 return error;
4463}
4464
4465/*
4466 * Lookup the transaction recovery structure associated with the ID in the
4467 * current ophdr. If the transaction doesn't exist and the start flag is set in
4468 * the ophdr, then allocate a new transaction for future ID matches to find.
4469 * Either way, return what we found during the lookup - an existing transaction
4470 * or nothing.
4471 */
4472STATIC struct xlog_recover *
4473xlog_recover_ophdr_to_trans(
4474 struct hlist_head rhash[],
4475 struct xlog_rec_header *rhead,
4476 struct xlog_op_header *ohead)
4477{
4478 struct xlog_recover *trans;
4479 xlog_tid_t tid;
4480 struct hlist_head *rhp;
4481
4482 tid = be32_to_cpu(ohead->oh_tid);
4483 rhp = &rhash[XLOG_RHASH(tid)];
4484 hlist_for_each_entry(trans, rhp, r_list) {
4485 if (trans->r_log_tid == tid)
4486 return trans;
4487 }
4488
4489 /*
4490 * skip over non-start transaction headers - we could be
4491 * processing slack space before the next transaction starts
4492 */
4493 if (!(ohead->oh_flags & XLOG_START_TRANS))
4494 return NULL;
4495
4496 ASSERT(be32_to_cpu(ohead->oh_len) == 0);
4497
4498 /*
4499 * This is a new transaction so allocate a new recovery container to
4500 * hold the recovery ops that will follow.
4501 */
4502 trans = kmem_zalloc(sizeof(struct xlog_recover), KM_SLEEP);
4503 trans->r_log_tid = tid;
4504 trans->r_lsn = be64_to_cpu(rhead->h_lsn);
4505 INIT_LIST_HEAD(&trans->r_itemq);
4506 INIT_HLIST_NODE(&trans->r_list);
4507 hlist_add_head(&trans->r_list, rhp);
4508
4509 /*
4510 * Nothing more to do for this ophdr. Items to be added to this new
4511 * transaction will be in subsequent ophdr containers.
4512 */
4513 return NULL;
4514}
4515
4516STATIC int
4517xlog_recover_process_ophdr(
4518 struct xlog *log,
4519 struct hlist_head rhash[],
4520 struct xlog_rec_header *rhead,
4521 struct xlog_op_header *ohead,
4522 char *dp,
4523 char *end,
4524 int pass,
4525 struct list_head *buffer_list)
4526{
4527 struct xlog_recover *trans;
4528 unsigned int len;
4529 int error;
4530
4531 /* Do we understand who wrote this op? */
4532 if (ohead->oh_clientid != XFS_TRANSACTION &&
4533 ohead->oh_clientid != XFS_LOG) {
4534 xfs_warn(log->l_mp, "%s: bad clientid 0x%x",
4535 __func__, ohead->oh_clientid);
4536 ASSERT(0);
4537 return -EIO;
4538 }
4539
4540 /*
4541 * Check the ophdr contains all the data it is supposed to contain.
4542 */
4543 len = be32_to_cpu(ohead->oh_len);
4544 if (dp + len > end) {
4545 xfs_warn(log->l_mp, "%s: bad length 0x%x", __func__, len);
4546 WARN_ON(1);
4547 return -EIO;
4548 }
4549
4550 trans = xlog_recover_ophdr_to_trans(rhash, rhead, ohead);
4551 if (!trans) {
4552 /* nothing to do, so skip over this ophdr */
4553 return 0;
4554 }
4555
4556 /*
4557 * The recovered buffer queue is drained only once we know that all
4558 * recovery items for the current LSN have been processed. This is
4559 * required because:
4560 *
4561 * - Buffer write submission updates the metadata LSN of the buffer.
4562 * - Log recovery skips items with a metadata LSN >= the current LSN of
4563 * the recovery item.
4564 * - Separate recovery items against the same metadata buffer can share
4565 * a current LSN. I.e., consider that the LSN of a recovery item is
4566 * defined as the starting LSN of the first record in which its
4567 * transaction appears, that a record can hold multiple transactions,
4568 * and/or that a transaction can span multiple records.
4569 *
4570 * In other words, we are allowed to submit a buffer from log recovery
4571 * once per current LSN. Otherwise, we may incorrectly skip recovery
4572 * items and cause corruption.
4573 *
4574 * We don't know up front whether buffers are updated multiple times per
4575 * LSN. Therefore, track the current LSN of each commit log record as it
4576 * is processed and drain the queue when it changes. Use commit records
4577 * because they are ordered correctly by the logging code.
4578 */
4579 if (log->l_recovery_lsn != trans->r_lsn &&
4580 ohead->oh_flags & XLOG_COMMIT_TRANS) {
4581 error = xfs_buf_delwri_submit(buffer_list);
4582 if (error)
4583 return error;
4584 log->l_recovery_lsn = trans->r_lsn;
4585 }
4586
4587 return xlog_recovery_process_trans(log, trans, dp, len,
4588 ohead->oh_flags, pass, buffer_list);
4589}
4590
4591/*
4592 * There are two valid states of the r_state field. 0 indicates that the
4593 * transaction structure is in a normal state. We have either seen the
4594 * start of the transaction or the last operation we added was not a partial
4595 * operation. If the last operation we added to the transaction was a
4596 * partial operation, we need to mark r_state with XLOG_WAS_CONT_TRANS.
4597 *
4598 * NOTE: skip LRs with 0 data length.
4599 */
4600STATIC int
4601xlog_recover_process_data(
4602 struct xlog *log,
4603 struct hlist_head rhash[],
4604 struct xlog_rec_header *rhead,
4605 char *dp,
4606 int pass,
4607 struct list_head *buffer_list)
4608{
4609 struct xlog_op_header *ohead;
4610 char *end;
4611 int num_logops;
4612 int error;
4613
4614 end = dp + be32_to_cpu(rhead->h_len);
4615 num_logops = be32_to_cpu(rhead->h_num_logops);
4616
4617 /* check the log format matches our own - else we can't recover */
4618 if (xlog_header_check_recover(log->l_mp, rhead))
4619 return -EIO;
4620
4621 trace_xfs_log_recover_record(log, rhead, pass);
4622 while ((dp < end) && num_logops) {
4623
4624 ohead = (struct xlog_op_header *)dp;
4625 dp += sizeof(*ohead);
4626 ASSERT(dp <= end);
4627
4628 /* errors will abort recovery */
4629 error = xlog_recover_process_ophdr(log, rhash, rhead, ohead,
4630 dp, end, pass, buffer_list);
4631 if (error)
4632 return error;
4633
4634 dp += be32_to_cpu(ohead->oh_len);
4635 num_logops--;
4636 }
4637 return 0;
4638}
4639
4640/* Recover the EFI if necessary. */
4641STATIC int
4642xlog_recover_process_efi(
4643 struct xfs_mount *mp,
4644 struct xfs_ail *ailp,
4645 struct xfs_log_item *lip)
4646{
4647 struct xfs_efi_log_item *efip;
4648 int error;
4649
4650 /*
4651 * Skip EFIs that we've already processed.
4652 */
4653 efip = container_of(lip, struct xfs_efi_log_item, efi_item);
4654 if (test_bit(XFS_EFI_RECOVERED, &efip->efi_flags))
4655 return 0;
4656
4657 spin_unlock(&ailp->ail_lock);
4658 error = xfs_efi_recover(mp, efip);
4659 spin_lock(&ailp->ail_lock);
4660
4661 return error;
4662}
4663
4664/* Release the EFI since we're cancelling everything. */
4665STATIC void
4666xlog_recover_cancel_efi(
4667 struct xfs_mount *mp,
4668 struct xfs_ail *ailp,
4669 struct xfs_log_item *lip)
4670{
4671 struct xfs_efi_log_item *efip;
4672
4673 efip = container_of(lip, struct xfs_efi_log_item, efi_item);
4674
4675 spin_unlock(&ailp->ail_lock);
4676 xfs_efi_release(efip);
4677 spin_lock(&ailp->ail_lock);
4678}
4679
4680/* Recover the RUI if necessary. */
4681STATIC int
4682xlog_recover_process_rui(
4683 struct xfs_mount *mp,
4684 struct xfs_ail *ailp,
4685 struct xfs_log_item *lip)
4686{
4687 struct xfs_rui_log_item *ruip;
4688 int error;
4689
4690 /*
4691 * Skip RUIs that we've already processed.
4692 */
4693 ruip = container_of(lip, struct xfs_rui_log_item, rui_item);
4694 if (test_bit(XFS_RUI_RECOVERED, &ruip->rui_flags))
4695 return 0;
4696
4697 spin_unlock(&ailp->ail_lock);
4698 error = xfs_rui_recover(mp, ruip);
4699 spin_lock(&ailp->ail_lock);
4700
4701 return error;
4702}
4703
4704/* Release the RUI since we're cancelling everything. */
4705STATIC void
4706xlog_recover_cancel_rui(
4707 struct xfs_mount *mp,
4708 struct xfs_ail *ailp,
4709 struct xfs_log_item *lip)
4710{
4711 struct xfs_rui_log_item *ruip;
4712
4713 ruip = container_of(lip, struct xfs_rui_log_item, rui_item);
4714
4715 spin_unlock(&ailp->ail_lock);
4716 xfs_rui_release(ruip);
4717 spin_lock(&ailp->ail_lock);
4718}
4719
4720/* Recover the CUI if necessary. */
4721STATIC int
4722xlog_recover_process_cui(
4723 struct xfs_mount *mp,
4724 struct xfs_ail *ailp,
4725 struct xfs_log_item *lip,
4726 struct xfs_defer_ops *dfops)
4727{
4728 struct xfs_cui_log_item *cuip;
4729 int error;
4730
4731 /*
4732 * Skip CUIs that we've already processed.
4733 */
4734 cuip = container_of(lip, struct xfs_cui_log_item, cui_item);
4735 if (test_bit(XFS_CUI_RECOVERED, &cuip->cui_flags))
4736 return 0;
4737
4738 spin_unlock(&ailp->ail_lock);
4739 error = xfs_cui_recover(mp, cuip, dfops);
4740 spin_lock(&ailp->ail_lock);
4741
4742 return error;
4743}
4744
4745/* Release the CUI since we're cancelling everything. */
4746STATIC void
4747xlog_recover_cancel_cui(
4748 struct xfs_mount *mp,
4749 struct xfs_ail *ailp,
4750 struct xfs_log_item *lip)
4751{
4752 struct xfs_cui_log_item *cuip;
4753
4754 cuip = container_of(lip, struct xfs_cui_log_item, cui_item);
4755
4756 spin_unlock(&ailp->ail_lock);
4757 xfs_cui_release(cuip);
4758 spin_lock(&ailp->ail_lock);
4759}
4760
4761/* Recover the BUI if necessary. */
4762STATIC int
4763xlog_recover_process_bui(
4764 struct xfs_mount *mp,
4765 struct xfs_ail *ailp,
4766 struct xfs_log_item *lip,
4767 struct xfs_defer_ops *dfops)
4768{
4769 struct xfs_bui_log_item *buip;
4770 int error;
4771
4772 /*
4773 * Skip BUIs that we've already processed.
4774 */
4775 buip = container_of(lip, struct xfs_bui_log_item, bui_item);
4776 if (test_bit(XFS_BUI_RECOVERED, &buip->bui_flags))
4777 return 0;
4778
4779 spin_unlock(&ailp->ail_lock);
4780 error = xfs_bui_recover(mp, buip, dfops);
4781 spin_lock(&ailp->ail_lock);
4782
4783 return error;
4784}
4785
4786/* Release the BUI since we're cancelling everything. */
4787STATIC void
4788xlog_recover_cancel_bui(
4789 struct xfs_mount *mp,
4790 struct xfs_ail *ailp,
4791 struct xfs_log_item *lip)
4792{
4793 struct xfs_bui_log_item *buip;
4794
4795 buip = container_of(lip, struct xfs_bui_log_item, bui_item);
4796
4797 spin_unlock(&ailp->ail_lock);
4798 xfs_bui_release(buip);
4799 spin_lock(&ailp->ail_lock);
4800}
4801
4802/* Is this log item a deferred action intent? */
4803static inline bool xlog_item_is_intent(struct xfs_log_item *lip)
4804{
4805 switch (lip->li_type) {
4806 case XFS_LI_EFI:
4807 case XFS_LI_RUI:
4808 case XFS_LI_CUI:
4809 case XFS_LI_BUI:
4810 return true;
4811 default:
4812 return false;
4813 }
4814}
4815
4816/* Take all the collected deferred ops and finish them in order. */
4817static int
4818xlog_finish_defer_ops(
4819 struct xfs_mount *mp,
4820 struct xfs_defer_ops *dfops)
4821{
4822 struct xfs_trans *tp;
4823 int64_t freeblks;
4824 uint resblks;
4825 int error;
4826
4827 /*
4828 * We're finishing the defer_ops that accumulated as a result of
4829 * recovering unfinished intent items during log recovery. We
4830 * reserve an itruncate transaction because it is the largest
4831 * permanent transaction type. Since we're the only user of the fs
4832 * right now, take 93% (15/16) of the available free blocks. Use
4833 * weird math to avoid a 64-bit division.
4834 */
4835 freeblks = percpu_counter_sum(&mp->m_fdblocks);
4836 if (freeblks <= 0)
4837 return -ENOSPC;
4838 resblks = min_t(int64_t, UINT_MAX, freeblks);
4839 resblks = (resblks * 15) >> 4;
4840 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_itruncate, resblks,
4841 0, XFS_TRANS_RESERVE, &tp);
4842 if (error)
4843 return error;
4844
4845 error = xfs_defer_finish(&tp, dfops);
4846 if (error)
4847 goto out_cancel;
4848
4849 return xfs_trans_commit(tp);
4850
4851out_cancel:
4852 xfs_trans_cancel(tp);
4853 return error;
4854}
4855
4856/*
4857 * When this is called, all of the log intent items which did not have
4858 * corresponding log done items should be in the AIL. What we do now
4859 * is update the data structures associated with each one.
4860 *
4861 * Since we process the log intent items in normal transactions, they
4862 * will be removed at some point after the commit. This prevents us
4863 * from just walking down the list processing each one. We'll use a
4864 * flag in the intent item to skip those that we've already processed
4865 * and use the AIL iteration mechanism's generation count to try to
4866 * speed this up at least a bit.
4867 *
4868 * When we start, we know that the intents are the only things in the
4869 * AIL. As we process them, however, other items are added to the
4870 * AIL.
4871 */
4872STATIC int
4873xlog_recover_process_intents(
4874 struct xlog *log)
4875{
4876 struct xfs_defer_ops dfops;
4877 struct xfs_ail_cursor cur;
4878 struct xfs_log_item *lip;
4879 struct xfs_ail *ailp;
4880 xfs_fsblock_t firstfsb;
4881 int error = 0;
4882#if defined(DEBUG) || defined(XFS_WARN)
4883 xfs_lsn_t last_lsn;
4884#endif
4885
4886 ailp = log->l_ailp;
4887 spin_lock(&ailp->ail_lock);
4888 lip = xfs_trans_ail_cursor_first(ailp, &cur, 0);
4889#if defined(DEBUG) || defined(XFS_WARN)
4890 last_lsn = xlog_assign_lsn(log->l_curr_cycle, log->l_curr_block);
4891#endif
4892 xfs_defer_init(&dfops, &firstfsb);
4893 while (lip != NULL) {
4894 /*
4895 * We're done when we see something other than an intent.
4896 * There should be no intents left in the AIL now.
4897 */
4898 if (!xlog_item_is_intent(lip)) {
4899#ifdef DEBUG
4900 for (; lip; lip = xfs_trans_ail_cursor_next(ailp, &cur))
4901 ASSERT(!xlog_item_is_intent(lip));
4902#endif
4903 break;
4904 }
4905
4906 /*
4907 * We should never see a redo item with a LSN higher than
4908 * the last transaction we found in the log at the start
4909 * of recovery.
4910 */
4911 ASSERT(XFS_LSN_CMP(last_lsn, lip->li_lsn) >= 0);
4912
4913 /*
4914 * NOTE: If your intent processing routine can create more
4915 * deferred ops, you /must/ attach them to the dfops in this
4916 * routine or else those subsequent intents will get
4917 * replayed in the wrong order!
4918 */
4919 switch (lip->li_type) {
4920 case XFS_LI_EFI:
4921 error = xlog_recover_process_efi(log->l_mp, ailp, lip);
4922 break;
4923 case XFS_LI_RUI:
4924 error = xlog_recover_process_rui(log->l_mp, ailp, lip);
4925 break;
4926 case XFS_LI_CUI:
4927 error = xlog_recover_process_cui(log->l_mp, ailp, lip,
4928 &dfops);
4929 break;
4930 case XFS_LI_BUI:
4931 error = xlog_recover_process_bui(log->l_mp, ailp, lip,
4932 &dfops);
4933 break;
4934 }
4935 if (error)
4936 goto out;
4937 lip = xfs_trans_ail_cursor_next(ailp, &cur);
4938 }
4939out:
4940 xfs_trans_ail_cursor_done(&cur);
4941 spin_unlock(&ailp->ail_lock);
4942 if (error)
4943 xfs_defer_cancel(&dfops);
4944 else
4945 error = xlog_finish_defer_ops(log->l_mp, &dfops);
4946
4947 return error;
4948}
4949
4950/*
4951 * A cancel occurs when the mount has failed and we're bailing out.
4952 * Release all pending log intent items so they don't pin the AIL.
4953 */
4954STATIC int
4955xlog_recover_cancel_intents(
4956 struct xlog *log)
4957{
4958 struct xfs_log_item *lip;
4959 int error = 0;
4960 struct xfs_ail_cursor cur;
4961 struct xfs_ail *ailp;
4962
4963 ailp = log->l_ailp;
4964 spin_lock(&ailp->ail_lock);
4965 lip = xfs_trans_ail_cursor_first(ailp, &cur, 0);
4966 while (lip != NULL) {
4967 /*
4968 * We're done when we see something other than an intent.
4969 * There should be no intents left in the AIL now.
4970 */
4971 if (!xlog_item_is_intent(lip)) {
4972#ifdef DEBUG
4973 for (; lip; lip = xfs_trans_ail_cursor_next(ailp, &cur))
4974 ASSERT(!xlog_item_is_intent(lip));
4975#endif
4976 break;
4977 }
4978
4979 switch (lip->li_type) {
4980 case XFS_LI_EFI:
4981 xlog_recover_cancel_efi(log->l_mp, ailp, lip);
4982 break;
4983 case XFS_LI_RUI:
4984 xlog_recover_cancel_rui(log->l_mp, ailp, lip);
4985 break;
4986 case XFS_LI_CUI:
4987 xlog_recover_cancel_cui(log->l_mp, ailp, lip);
4988 break;
4989 case XFS_LI_BUI:
4990 xlog_recover_cancel_bui(log->l_mp, ailp, lip);
4991 break;
4992 }
4993
4994 lip = xfs_trans_ail_cursor_next(ailp, &cur);
4995 }
4996
4997 xfs_trans_ail_cursor_done(&cur);
4998 spin_unlock(&ailp->ail_lock);
4999 return error;
5000}
5001
5002/*
5003 * This routine performs a transaction to null out a bad inode pointer
5004 * in an agi unlinked inode hash bucket.
5005 */
5006STATIC void
5007xlog_recover_clear_agi_bucket(
5008 xfs_mount_t *mp,
5009 xfs_agnumber_t agno,
5010 int bucket)
5011{
5012 xfs_trans_t *tp;
5013 xfs_agi_t *agi;
5014 xfs_buf_t *agibp;
5015 int offset;
5016 int error;
5017
5018 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_clearagi, 0, 0, 0, &tp);
5019 if (error)
5020 goto out_error;
5021
5022 error = xfs_read_agi(mp, tp, agno, &agibp);
5023 if (error)
5024 goto out_abort;
5025
5026 agi = XFS_BUF_TO_AGI(agibp);
5027 agi->agi_unlinked[bucket] = cpu_to_be32(NULLAGINO);
5028 offset = offsetof(xfs_agi_t, agi_unlinked) +
5029 (sizeof(xfs_agino_t) * bucket);
5030 xfs_trans_log_buf(tp, agibp, offset,
5031 (offset + sizeof(xfs_agino_t) - 1));
5032
5033 error = xfs_trans_commit(tp);
5034 if (error)
5035 goto out_error;
5036 return;
5037
5038out_abort:
5039 xfs_trans_cancel(tp);
5040out_error:
5041 xfs_warn(mp, "%s: failed to clear agi %d. Continuing.", __func__, agno);
5042 return;
5043}
5044
5045STATIC xfs_agino_t
5046xlog_recover_process_one_iunlink(
5047 struct xfs_mount *mp,
5048 xfs_agnumber_t agno,
5049 xfs_agino_t agino,
5050 int bucket)
5051{
5052 struct xfs_buf *ibp;
5053 struct xfs_dinode *dip;
5054 struct xfs_inode *ip;
5055 xfs_ino_t ino;
5056 int error;
5057
5058 ino = XFS_AGINO_TO_INO(mp, agno, agino);
5059 error = xfs_iget(mp, NULL, ino, 0, 0, &ip);
5060 if (error)
5061 goto fail;
5062
5063 /*
5064 * Get the on disk inode to find the next inode in the bucket.
5065 */
5066 error = xfs_imap_to_bp(mp, NULL, &ip->i_imap, &dip, &ibp, 0, 0);
5067 if (error)
5068 goto fail_iput;
5069
5070 xfs_iflags_clear(ip, XFS_IRECOVERY);
5071 ASSERT(VFS_I(ip)->i_nlink == 0);
5072 ASSERT(VFS_I(ip)->i_mode != 0);
5073
5074 /* setup for the next pass */
5075 agino = be32_to_cpu(dip->di_next_unlinked);
5076 xfs_buf_relse(ibp);
5077
5078 /*
5079 * Prevent any DMAPI event from being sent when the reference on
5080 * the inode is dropped.
5081 */
5082 ip->i_d.di_dmevmask = 0;
5083
5084 IRELE(ip);
5085 return agino;
5086
5087 fail_iput:
5088 IRELE(ip);
5089 fail:
5090 /*
5091 * We can't read in the inode this bucket points to, or this inode
5092 * is messed up. Just ditch this bucket of inodes. We will lose
5093 * some inodes and space, but at least we won't hang.
5094 *
5095 * Call xlog_recover_clear_agi_bucket() to perform a transaction to
5096 * clear the inode pointer in the bucket.
5097 */
5098 xlog_recover_clear_agi_bucket(mp, agno, bucket);
5099 return NULLAGINO;
5100}
5101
5102/*
5103 * xlog_iunlink_recover
5104 *
5105 * This is called during recovery to process any inodes which
5106 * we unlinked but not freed when the system crashed. These
5107 * inodes will be on the lists in the AGI blocks. What we do
5108 * here is scan all the AGIs and fully truncate and free any
5109 * inodes found on the lists. Each inode is removed from the
5110 * lists when it has been fully truncated and is freed. The
5111 * freeing of the inode and its removal from the list must be
5112 * atomic.
5113 */
5114STATIC void
5115xlog_recover_process_iunlinks(
5116 struct xlog *log)
5117{
5118 xfs_mount_t *mp;
5119 xfs_agnumber_t agno;
5120 xfs_agi_t *agi;
5121 xfs_buf_t *agibp;
5122 xfs_agino_t agino;
5123 int bucket;
5124 int error;
5125
5126 mp = log->l_mp;
5127
5128 for (agno = 0; agno < mp->m_sb.sb_agcount; agno++) {
5129 /*
5130 * Find the agi for this ag.
5131 */
5132 error = xfs_read_agi(mp, NULL, agno, &agibp);
5133 if (error) {
5134 /*
5135 * AGI is b0rked. Don't process it.
5136 *
5137 * We should probably mark the filesystem as corrupt
5138 * after we've recovered all the ag's we can....
5139 */
5140 continue;
5141 }
5142 /*
5143 * Unlock the buffer so that it can be acquired in the normal
5144 * course of the transaction to truncate and free each inode.
5145 * Because we are not racing with anyone else here for the AGI
5146 * buffer, we don't even need to hold it locked to read the
5147 * initial unlinked bucket entries out of the buffer. We keep
5148 * buffer reference though, so that it stays pinned in memory
5149 * while we need the buffer.
5150 */
5151 agi = XFS_BUF_TO_AGI(agibp);
5152 xfs_buf_unlock(agibp);
5153
5154 for (bucket = 0; bucket < XFS_AGI_UNLINKED_BUCKETS; bucket++) {
5155 agino = be32_to_cpu(agi->agi_unlinked[bucket]);
5156 while (agino != NULLAGINO) {
5157 agino = xlog_recover_process_one_iunlink(mp,
5158 agno, agino, bucket);
5159 }
5160 }
5161 xfs_buf_rele(agibp);
5162 }
5163}
5164
5165STATIC int
5166xlog_unpack_data(
5167 struct xlog_rec_header *rhead,
5168 char *dp,
5169 struct xlog *log)
5170{
5171 int i, j, k;
5172
5173 for (i = 0; i < BTOBB(be32_to_cpu(rhead->h_len)) &&
5174 i < (XLOG_HEADER_CYCLE_SIZE / BBSIZE); i++) {
5175 *(__be32 *)dp = *(__be32 *)&rhead->h_cycle_data[i];
5176 dp += BBSIZE;
5177 }
5178
5179 if (xfs_sb_version_haslogv2(&log->l_mp->m_sb)) {
5180 xlog_in_core_2_t *xhdr = (xlog_in_core_2_t *)rhead;
5181 for ( ; i < BTOBB(be32_to_cpu(rhead->h_len)); i++) {
5182 j = i / (XLOG_HEADER_CYCLE_SIZE / BBSIZE);
5183 k = i % (XLOG_HEADER_CYCLE_SIZE / BBSIZE);
5184 *(__be32 *)dp = xhdr[j].hic_xheader.xh_cycle_data[k];
5185 dp += BBSIZE;
5186 }
5187 }
5188
5189 return 0;
5190}
5191
5192/*
5193 * CRC check, unpack and process a log record.
5194 */
5195STATIC int
5196xlog_recover_process(
5197 struct xlog *log,
5198 struct hlist_head rhash[],
5199 struct xlog_rec_header *rhead,
5200 char *dp,
5201 int pass,
5202 struct list_head *buffer_list)
5203{
5204 int error;
5205 __le32 old_crc = rhead->h_crc;
5206 __le32 crc;
5207
5208
5209 crc = xlog_cksum(log, rhead, dp, be32_to_cpu(rhead->h_len));
5210
5211 /*
5212 * Nothing else to do if this is a CRC verification pass. Just return
5213 * if this a record with a non-zero crc. Unfortunately, mkfs always
5214 * sets old_crc to 0 so we must consider this valid even on v5 supers.
5215 * Otherwise, return EFSBADCRC on failure so the callers up the stack
5216 * know precisely what failed.
5217 */
5218 if (pass == XLOG_RECOVER_CRCPASS) {
5219 if (old_crc && crc != old_crc)
5220 return -EFSBADCRC;
5221 return 0;
5222 }
5223
5224 /*
5225 * We're in the normal recovery path. Issue a warning if and only if the
5226 * CRC in the header is non-zero. This is an advisory warning and the
5227 * zero CRC check prevents warnings from being emitted when upgrading
5228 * the kernel from one that does not add CRCs by default.
5229 */
5230 if (crc != old_crc) {
5231 if (old_crc || xfs_sb_version_hascrc(&log->l_mp->m_sb)) {
5232 xfs_alert(log->l_mp,
5233 "log record CRC mismatch: found 0x%x, expected 0x%x.",
5234 le32_to_cpu(old_crc),
5235 le32_to_cpu(crc));
5236 xfs_hex_dump(dp, 32);
5237 }
5238
5239 /*
5240 * If the filesystem is CRC enabled, this mismatch becomes a
5241 * fatal log corruption failure.
5242 */
5243 if (xfs_sb_version_hascrc(&log->l_mp->m_sb))
5244 return -EFSCORRUPTED;
5245 }
5246
5247 error = xlog_unpack_data(rhead, dp, log);
5248 if (error)
5249 return error;
5250
5251 return xlog_recover_process_data(log, rhash, rhead, dp, pass,
5252 buffer_list);
5253}
5254
5255STATIC int
5256xlog_valid_rec_header(
5257 struct xlog *log,
5258 struct xlog_rec_header *rhead,
5259 xfs_daddr_t blkno)
5260{
5261 int hlen;
5262
5263 if (unlikely(rhead->h_magicno != cpu_to_be32(XLOG_HEADER_MAGIC_NUM))) {
5264 XFS_ERROR_REPORT("xlog_valid_rec_header(1)",
5265 XFS_ERRLEVEL_LOW, log->l_mp);
5266 return -EFSCORRUPTED;
5267 }
5268 if (unlikely(
5269 (!rhead->h_version ||
5270 (be32_to_cpu(rhead->h_version) & (~XLOG_VERSION_OKBITS))))) {
5271 xfs_warn(log->l_mp, "%s: unrecognised log version (%d).",
5272 __func__, be32_to_cpu(rhead->h_version));
5273 return -EIO;
5274 }
5275
5276 /* LR body must have data or it wouldn't have been written */
5277 hlen = be32_to_cpu(rhead->h_len);
5278 if (unlikely( hlen <= 0 || hlen > INT_MAX )) {
5279 XFS_ERROR_REPORT("xlog_valid_rec_header(2)",
5280 XFS_ERRLEVEL_LOW, log->l_mp);
5281 return -EFSCORRUPTED;
5282 }
5283 if (unlikely( blkno > log->l_logBBsize || blkno > INT_MAX )) {
5284 XFS_ERROR_REPORT("xlog_valid_rec_header(3)",
5285 XFS_ERRLEVEL_LOW, log->l_mp);
5286 return -EFSCORRUPTED;
5287 }
5288 return 0;
5289}
5290
5291/*
5292 * Read the log from tail to head and process the log records found.
5293 * Handle the two cases where the tail and head are in the same cycle
5294 * and where the active portion of the log wraps around the end of
5295 * the physical log separately. The pass parameter is passed through
5296 * to the routines called to process the data and is not looked at
5297 * here.
5298 */
5299STATIC int
5300xlog_do_recovery_pass(
5301 struct xlog *log,
5302 xfs_daddr_t head_blk,
5303 xfs_daddr_t tail_blk,
5304 int pass,
5305 xfs_daddr_t *first_bad) /* out: first bad log rec */
5306{
5307 xlog_rec_header_t *rhead;
5308 xfs_daddr_t blk_no, rblk_no;
5309 xfs_daddr_t rhead_blk;
5310 char *offset;
5311 xfs_buf_t *hbp, *dbp;
5312 int error = 0, h_size, h_len;
5313 int error2 = 0;
5314 int bblks, split_bblks;
5315 int hblks, split_hblks, wrapped_hblks;
5316 int i;
5317 struct hlist_head rhash[XLOG_RHASH_SIZE];
5318 LIST_HEAD (buffer_list);
5319
5320 ASSERT(head_blk != tail_blk);
5321 blk_no = rhead_blk = tail_blk;
5322
5323 for (i = 0; i < XLOG_RHASH_SIZE; i++)
5324 INIT_HLIST_HEAD(&rhash[i]);
5325
5326 /*
5327 * Read the header of the tail block and get the iclog buffer size from
5328 * h_size. Use this to tell how many sectors make up the log header.
5329 */
5330 if (xfs_sb_version_haslogv2(&log->l_mp->m_sb)) {
5331 /*
5332 * When using variable length iclogs, read first sector of
5333 * iclog header and extract the header size from it. Get a
5334 * new hbp that is the correct size.
5335 */
5336 hbp = xlog_get_bp(log, 1);
5337 if (!hbp)
5338 return -ENOMEM;
5339
5340 error = xlog_bread(log, tail_blk, 1, hbp, &offset);
5341 if (error)
5342 goto bread_err1;
5343
5344 rhead = (xlog_rec_header_t *)offset;
5345 error = xlog_valid_rec_header(log, rhead, tail_blk);
5346 if (error)
5347 goto bread_err1;
5348
5349 /*
5350 * xfsprogs has a bug where record length is based on lsunit but
5351 * h_size (iclog size) is hardcoded to 32k. Now that we
5352 * unconditionally CRC verify the unmount record, this means the
5353 * log buffer can be too small for the record and cause an
5354 * overrun.
5355 *
5356 * Detect this condition here. Use lsunit for the buffer size as
5357 * long as this looks like the mkfs case. Otherwise, return an
5358 * error to avoid a buffer overrun.
5359 */
5360 h_size = be32_to_cpu(rhead->h_size);
5361 h_len = be32_to_cpu(rhead->h_len);
5362 if (h_len > h_size) {
5363 if (h_len <= log->l_mp->m_logbsize &&
5364 be32_to_cpu(rhead->h_num_logops) == 1) {
5365 xfs_warn(log->l_mp,
5366 "invalid iclog size (%d bytes), using lsunit (%d bytes)",
5367 h_size, log->l_mp->m_logbsize);
5368 h_size = log->l_mp->m_logbsize;
5369 } else
5370 return -EFSCORRUPTED;
5371 }
5372
5373 if ((be32_to_cpu(rhead->h_version) & XLOG_VERSION_2) &&
5374 (h_size > XLOG_HEADER_CYCLE_SIZE)) {
5375 hblks = h_size / XLOG_HEADER_CYCLE_SIZE;
5376 if (h_size % XLOG_HEADER_CYCLE_SIZE)
5377 hblks++;
5378 xlog_put_bp(hbp);
5379 hbp = xlog_get_bp(log, hblks);
5380 } else {
5381 hblks = 1;
5382 }
5383 } else {
5384 ASSERT(log->l_sectBBsize == 1);
5385 hblks = 1;
5386 hbp = xlog_get_bp(log, 1);
5387 h_size = XLOG_BIG_RECORD_BSIZE;
5388 }
5389
5390 if (!hbp)
5391 return -ENOMEM;
5392 dbp = xlog_get_bp(log, BTOBB(h_size));
5393 if (!dbp) {
5394 xlog_put_bp(hbp);
5395 return -ENOMEM;
5396 }
5397
5398 memset(rhash, 0, sizeof(rhash));
5399 if (tail_blk > head_blk) {
5400 /*
5401 * Perform recovery around the end of the physical log.
5402 * When the head is not on the same cycle number as the tail,
5403 * we can't do a sequential recovery.
5404 */
5405 while (blk_no < log->l_logBBsize) {
5406 /*
5407 * Check for header wrapping around physical end-of-log
5408 */
5409 offset = hbp->b_addr;
5410 split_hblks = 0;
5411 wrapped_hblks = 0;
5412 if (blk_no + hblks <= log->l_logBBsize) {
5413 /* Read header in one read */
5414 error = xlog_bread(log, blk_no, hblks, hbp,
5415 &offset);
5416 if (error)
5417 goto bread_err2;
5418 } else {
5419 /* This LR is split across physical log end */
5420 if (blk_no != log->l_logBBsize) {
5421 /* some data before physical log end */
5422 ASSERT(blk_no <= INT_MAX);
5423 split_hblks = log->l_logBBsize - (int)blk_no;
5424 ASSERT(split_hblks > 0);
5425 error = xlog_bread(log, blk_no,
5426 split_hblks, hbp,
5427 &offset);
5428 if (error)
5429 goto bread_err2;
5430 }
5431
5432 /*
5433 * Note: this black magic still works with
5434 * large sector sizes (non-512) only because:
5435 * - we increased the buffer size originally
5436 * by 1 sector giving us enough extra space
5437 * for the second read;
5438 * - the log start is guaranteed to be sector
5439 * aligned;
5440 * - we read the log end (LR header start)
5441 * _first_, then the log start (LR header end)
5442 * - order is important.
5443 */
5444 wrapped_hblks = hblks - split_hblks;
5445 error = xlog_bread_offset(log, 0,
5446 wrapped_hblks, hbp,
5447 offset + BBTOB(split_hblks));
5448 if (error)
5449 goto bread_err2;
5450 }
5451 rhead = (xlog_rec_header_t *)offset;
5452 error = xlog_valid_rec_header(log, rhead,
5453 split_hblks ? blk_no : 0);
5454 if (error)
5455 goto bread_err2;
5456
5457 bblks = (int)BTOBB(be32_to_cpu(rhead->h_len));
5458 blk_no += hblks;
5459
5460 /*
5461 * Read the log record data in multiple reads if it
5462 * wraps around the end of the log. Note that if the
5463 * header already wrapped, blk_no could point past the
5464 * end of the log. The record data is contiguous in
5465 * that case.
5466 */
5467 if (blk_no + bblks <= log->l_logBBsize ||
5468 blk_no >= log->l_logBBsize) {
5469 /* mod blk_no in case the header wrapped and
5470 * pushed it beyond the end of the log */
5471 rblk_no = do_mod(blk_no, log->l_logBBsize);
5472 error = xlog_bread(log, rblk_no, bblks, dbp,
5473 &offset);
5474 if (error)
5475 goto bread_err2;
5476 } else {
5477 /* This log record is split across the
5478 * physical end of log */
5479 offset = dbp->b_addr;
5480 split_bblks = 0;
5481 if (blk_no != log->l_logBBsize) {
5482 /* some data is before the physical
5483 * end of log */
5484 ASSERT(!wrapped_hblks);
5485 ASSERT(blk_no <= INT_MAX);
5486 split_bblks =
5487 log->l_logBBsize - (int)blk_no;
5488 ASSERT(split_bblks > 0);
5489 error = xlog_bread(log, blk_no,
5490 split_bblks, dbp,
5491 &offset);
5492 if (error)
5493 goto bread_err2;
5494 }
5495
5496 /*
5497 * Note: this black magic still works with
5498 * large sector sizes (non-512) only because:
5499 * - we increased the buffer size originally
5500 * by 1 sector giving us enough extra space
5501 * for the second read;
5502 * - the log start is guaranteed to be sector
5503 * aligned;
5504 * - we read the log end (LR header start)
5505 * _first_, then the log start (LR header end)
5506 * - order is important.
5507 */
5508 error = xlog_bread_offset(log, 0,
5509 bblks - split_bblks, dbp,
5510 offset + BBTOB(split_bblks));
5511 if (error)
5512 goto bread_err2;
5513 }
5514
5515 error = xlog_recover_process(log, rhash, rhead, offset,
5516 pass, &buffer_list);
5517 if (error)
5518 goto bread_err2;
5519
5520 blk_no += bblks;
5521 rhead_blk = blk_no;
5522 }
5523
5524 ASSERT(blk_no >= log->l_logBBsize);
5525 blk_no -= log->l_logBBsize;
5526 rhead_blk = blk_no;
5527 }
5528
5529 /* read first part of physical log */
5530 while (blk_no < head_blk) {
5531 error = xlog_bread(log, blk_no, hblks, hbp, &offset);
5532 if (error)
5533 goto bread_err2;
5534
5535 rhead = (xlog_rec_header_t *)offset;
5536 error = xlog_valid_rec_header(log, rhead, blk_no);
5537 if (error)
5538 goto bread_err2;
5539
5540 /* blocks in data section */
5541 bblks = (int)BTOBB(be32_to_cpu(rhead->h_len));
5542 error = xlog_bread(log, blk_no+hblks, bblks, dbp,
5543 &offset);
5544 if (error)
5545 goto bread_err2;
5546
5547 error = xlog_recover_process(log, rhash, rhead, offset, pass,
5548 &buffer_list);
5549 if (error)
5550 goto bread_err2;
5551
5552 blk_no += bblks + hblks;
5553 rhead_blk = blk_no;
5554 }
5555
5556 bread_err2:
5557 xlog_put_bp(dbp);
5558 bread_err1:
5559 xlog_put_bp(hbp);
5560
5561 /*
5562 * Submit buffers that have been added from the last record processed,
5563 * regardless of error status.
5564 */
5565 if (!list_empty(&buffer_list))
5566 error2 = xfs_buf_delwri_submit(&buffer_list);
5567
5568 if (error && first_bad)
5569 *first_bad = rhead_blk;
5570
5571 /*
5572 * Transactions are freed at commit time but transactions without commit
5573 * records on disk are never committed. Free any that may be left in the
5574 * hash table.
5575 */
5576 for (i = 0; i < XLOG_RHASH_SIZE; i++) {
5577 struct hlist_node *tmp;
5578 struct xlog_recover *trans;
5579
5580 hlist_for_each_entry_safe(trans, tmp, &rhash[i], r_list)
5581 xlog_recover_free_trans(trans);
5582 }
5583
5584 return error ? error : error2;
5585}
5586
5587/*
5588 * Do the recovery of the log. We actually do this in two phases.
5589 * The two passes are necessary in order to implement the function
5590 * of cancelling a record written into the log. The first pass
5591 * determines those things which have been cancelled, and the
5592 * second pass replays log items normally except for those which
5593 * have been cancelled. The handling of the replay and cancellations
5594 * takes place in the log item type specific routines.
5595 *
5596 * The table of items which have cancel records in the log is allocated
5597 * and freed at this level, since only here do we know when all of
5598 * the log recovery has been completed.
5599 */
5600STATIC int
5601xlog_do_log_recovery(
5602 struct xlog *log,
5603 xfs_daddr_t head_blk,
5604 xfs_daddr_t tail_blk)
5605{
5606 int error, i;
5607
5608 ASSERT(head_blk != tail_blk);
5609
5610 /*
5611 * First do a pass to find all of the cancelled buf log items.
5612 * Store them in the buf_cancel_table for use in the second pass.
5613 */
5614 log->l_buf_cancel_table = kmem_zalloc(XLOG_BC_TABLE_SIZE *
5615 sizeof(struct list_head),
5616 KM_SLEEP);
5617 for (i = 0; i < XLOG_BC_TABLE_SIZE; i++)
5618 INIT_LIST_HEAD(&log->l_buf_cancel_table[i]);
5619
5620 error = xlog_do_recovery_pass(log, head_blk, tail_blk,
5621 XLOG_RECOVER_PASS1, NULL);
5622 if (error != 0) {
5623 kmem_free(log->l_buf_cancel_table);
5624 log->l_buf_cancel_table = NULL;
5625 return error;
5626 }
5627 /*
5628 * Then do a second pass to actually recover the items in the log.
5629 * When it is complete free the table of buf cancel items.
5630 */
5631 error = xlog_do_recovery_pass(log, head_blk, tail_blk,
5632 XLOG_RECOVER_PASS2, NULL);
5633#ifdef DEBUG
5634 if (!error) {
5635 int i;
5636
5637 for (i = 0; i < XLOG_BC_TABLE_SIZE; i++)
5638 ASSERT(list_empty(&log->l_buf_cancel_table[i]));
5639 }
5640#endif /* DEBUG */
5641
5642 kmem_free(log->l_buf_cancel_table);
5643 log->l_buf_cancel_table = NULL;
5644
5645 return error;
5646}
5647
5648/*
5649 * Do the actual recovery
5650 */
5651STATIC int
5652xlog_do_recover(
5653 struct xlog *log,
5654 xfs_daddr_t head_blk,
5655 xfs_daddr_t tail_blk)
5656{
5657 struct xfs_mount *mp = log->l_mp;
5658 int error;
5659 xfs_buf_t *bp;
5660 xfs_sb_t *sbp;
5661
5662 trace_xfs_log_recover(log, head_blk, tail_blk);
5663
5664 /*
5665 * First replay the images in the log.
5666 */
5667 error = xlog_do_log_recovery(log, head_blk, tail_blk);
5668 if (error)
5669 return error;
5670
5671 /*
5672 * If IO errors happened during recovery, bail out.
5673 */
5674 if (XFS_FORCED_SHUTDOWN(mp)) {
5675 return -EIO;
5676 }
5677
5678 /*
5679 * We now update the tail_lsn since much of the recovery has completed
5680 * and there may be space available to use. If there were no extent
5681 * or iunlinks, we can free up the entire log and set the tail_lsn to
5682 * be the last_sync_lsn. This was set in xlog_find_tail to be the
5683 * lsn of the last known good LR on disk. If there are extent frees
5684 * or iunlinks they will have some entries in the AIL; so we look at
5685 * the AIL to determine how to set the tail_lsn.
5686 */
5687 xlog_assign_tail_lsn(mp);
5688
5689 /*
5690 * Now that we've finished replaying all buffer and inode
5691 * updates, re-read in the superblock and reverify it.
5692 */
5693 bp = xfs_getsb(mp, 0);
5694 bp->b_flags &= ~(XBF_DONE | XBF_ASYNC);
5695 ASSERT(!(bp->b_flags & XBF_WRITE));
5696 bp->b_flags |= XBF_READ;
5697 bp->b_ops = &xfs_sb_buf_ops;
5698
5699 error = xfs_buf_submit_wait(bp);
5700 if (error) {
5701 if (!XFS_FORCED_SHUTDOWN(mp)) {
5702 xfs_buf_ioerror_alert(bp, __func__);
5703 ASSERT(0);
5704 }
5705 xfs_buf_relse(bp);
5706 return error;
5707 }
5708
5709 /* Convert superblock from on-disk format */
5710 sbp = &mp->m_sb;
5711 xfs_sb_from_disk(sbp, XFS_BUF_TO_SBP(bp));
5712 xfs_buf_relse(bp);
5713
5714 /* re-initialise in-core superblock and geometry structures */
5715 xfs_reinit_percpu_counters(mp);
5716 error = xfs_initialize_perag(mp, sbp->sb_agcount, &mp->m_maxagi);
5717 if (error) {
5718 xfs_warn(mp, "Failed post-recovery per-ag init: %d", error);
5719 return error;
5720 }
5721 mp->m_alloc_set_aside = xfs_alloc_set_aside(mp);
5722
5723 xlog_recover_check_summary(log);
5724
5725 /* Normal transactions can now occur */
5726 log->l_flags &= ~XLOG_ACTIVE_RECOVERY;
5727 return 0;
5728}
5729
5730/*
5731 * Perform recovery and re-initialize some log variables in xlog_find_tail.
5732 *
5733 * Return error or zero.
5734 */
5735int
5736xlog_recover(
5737 struct xlog *log)
5738{
5739 xfs_daddr_t head_blk, tail_blk;
5740 int error;
5741
5742 /* find the tail of the log */
5743 error = xlog_find_tail(log, &head_blk, &tail_blk);
5744 if (error)
5745 return error;
5746
5747 /*
5748 * The superblock was read before the log was available and thus the LSN
5749 * could not be verified. Check the superblock LSN against the current
5750 * LSN now that it's known.
5751 */
5752 if (xfs_sb_version_hascrc(&log->l_mp->m_sb) &&
5753 !xfs_log_check_lsn(log->l_mp, log->l_mp->m_sb.sb_lsn))
5754 return -EINVAL;
5755
5756 if (tail_blk != head_blk) {
5757 /* There used to be a comment here:
5758 *
5759 * disallow recovery on read-only mounts. note -- mount
5760 * checks for ENOSPC and turns it into an intelligent
5761 * error message.
5762 * ...but this is no longer true. Now, unless you specify
5763 * NORECOVERY (in which case this function would never be
5764 * called), we just go ahead and recover. We do this all
5765 * under the vfs layer, so we can get away with it unless
5766 * the device itself is read-only, in which case we fail.
5767 */
5768 if ((error = xfs_dev_is_read_only(log->l_mp, "recovery"))) {
5769 return error;
5770 }
5771
5772 /*
5773 * Version 5 superblock log feature mask validation. We know the
5774 * log is dirty so check if there are any unknown log features
5775 * in what we need to recover. If there are unknown features
5776 * (e.g. unsupported transactions, then simply reject the
5777 * attempt at recovery before touching anything.
5778 */
5779 if (XFS_SB_VERSION_NUM(&log->l_mp->m_sb) == XFS_SB_VERSION_5 &&
5780 xfs_sb_has_incompat_log_feature(&log->l_mp->m_sb,
5781 XFS_SB_FEAT_INCOMPAT_LOG_UNKNOWN)) {
5782 xfs_warn(log->l_mp,
5783"Superblock has unknown incompatible log features (0x%x) enabled.",
5784 (log->l_mp->m_sb.sb_features_log_incompat &
5785 XFS_SB_FEAT_INCOMPAT_LOG_UNKNOWN));
5786 xfs_warn(log->l_mp,
5787"The log can not be fully and/or safely recovered by this kernel.");
5788 xfs_warn(log->l_mp,
5789"Please recover the log on a kernel that supports the unknown features.");
5790 return -EINVAL;
5791 }
5792
5793 /*
5794 * Delay log recovery if the debug hook is set. This is debug
5795 * instrumention to coordinate simulation of I/O failures with
5796 * log recovery.
5797 */
5798 if (xfs_globals.log_recovery_delay) {
5799 xfs_notice(log->l_mp,
5800 "Delaying log recovery for %d seconds.",
5801 xfs_globals.log_recovery_delay);
5802 msleep(xfs_globals.log_recovery_delay * 1000);
5803 }
5804
5805 xfs_notice(log->l_mp, "Starting recovery (logdev: %s)",
5806 log->l_mp->m_logname ? log->l_mp->m_logname
5807 : "internal");
5808
5809 error = xlog_do_recover(log, head_blk, tail_blk);
5810 log->l_flags |= XLOG_RECOVERY_NEEDED;
5811 }
5812 return error;
5813}
5814
5815/*
5816 * In the first part of recovery we replay inodes and buffers and build
5817 * up the list of extent free items which need to be processed. Here
5818 * we process the extent free items and clean up the on disk unlinked
5819 * inode lists. This is separated from the first part of recovery so
5820 * that the root and real-time bitmap inodes can be read in from disk in
5821 * between the two stages. This is necessary so that we can free space
5822 * in the real-time portion of the file system.
5823 */
5824int
5825xlog_recover_finish(
5826 struct xlog *log)
5827{
5828 /*
5829 * Now we're ready to do the transactions needed for the
5830 * rest of recovery. Start with completing all the extent
5831 * free intent records and then process the unlinked inode
5832 * lists. At this point, we essentially run in normal mode
5833 * except that we're still performing recovery actions
5834 * rather than accepting new requests.
5835 */
5836 if (log->l_flags & XLOG_RECOVERY_NEEDED) {
5837 int error;
5838 error = xlog_recover_process_intents(log);
5839 if (error) {
5840 xfs_alert(log->l_mp, "Failed to recover intents");
5841 return error;
5842 }
5843
5844 /*
5845 * Sync the log to get all the intents out of the AIL.
5846 * This isn't absolutely necessary, but it helps in
5847 * case the unlink transactions would have problems
5848 * pushing the intents out of the way.
5849 */
5850 xfs_log_force(log->l_mp, XFS_LOG_SYNC);
5851
5852 xlog_recover_process_iunlinks(log);
5853
5854 xlog_recover_check_summary(log);
5855
5856 xfs_notice(log->l_mp, "Ending recovery (logdev: %s)",
5857 log->l_mp->m_logname ? log->l_mp->m_logname
5858 : "internal");
5859 log->l_flags &= ~XLOG_RECOVERY_NEEDED;
5860 } else {
5861 xfs_info(log->l_mp, "Ending clean mount");
5862 }
5863 return 0;
5864}
5865
5866int
5867xlog_recover_cancel(
5868 struct xlog *log)
5869{
5870 int error = 0;
5871
5872 if (log->l_flags & XLOG_RECOVERY_NEEDED)
5873 error = xlog_recover_cancel_intents(log);
5874
5875 return error;
5876}
5877
5878#if defined(DEBUG)
5879/*
5880 * Read all of the agf and agi counters and check that they
5881 * are consistent with the superblock counters.
5882 */
5883STATIC void
5884xlog_recover_check_summary(
5885 struct xlog *log)
5886{
5887 xfs_mount_t *mp;
5888 xfs_agf_t *agfp;
5889 xfs_buf_t *agfbp;
5890 xfs_buf_t *agibp;
5891 xfs_agnumber_t agno;
5892 uint64_t freeblks;
5893 uint64_t itotal;
5894 uint64_t ifree;
5895 int error;
5896
5897 mp = log->l_mp;
5898
5899 freeblks = 0LL;
5900 itotal = 0LL;
5901 ifree = 0LL;
5902 for (agno = 0; agno < mp->m_sb.sb_agcount; agno++) {
5903 error = xfs_read_agf(mp, NULL, agno, 0, &agfbp);
5904 if (error) {
5905 xfs_alert(mp, "%s agf read failed agno %d error %d",
5906 __func__, agno, error);
5907 } else {
5908 agfp = XFS_BUF_TO_AGF(agfbp);
5909 freeblks += be32_to_cpu(agfp->agf_freeblks) +
5910 be32_to_cpu(agfp->agf_flcount);
5911 xfs_buf_relse(agfbp);
5912 }
5913
5914 error = xfs_read_agi(mp, NULL, agno, &agibp);
5915 if (error) {
5916 xfs_alert(mp, "%s agi read failed agno %d error %d",
5917 __func__, agno, error);
5918 } else {
5919 struct xfs_agi *agi = XFS_BUF_TO_AGI(agibp);
5920
5921 itotal += be32_to_cpu(agi->agi_count);
5922 ifree += be32_to_cpu(agi->agi_freecount);
5923 xfs_buf_relse(agibp);
5924 }
5925 }
5926}
5927#endif /* DEBUG */
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (c) 2000-2006 Silicon Graphics, Inc.
4 * All Rights Reserved.
5 */
6#include "xfs.h"
7#include "xfs_fs.h"
8#include "xfs_shared.h"
9#include "xfs_format.h"
10#include "xfs_log_format.h"
11#include "xfs_trans_resv.h"
12#include "xfs_bit.h"
13#include "xfs_sb.h"
14#include "xfs_mount.h"
15#include "xfs_defer.h"
16#include "xfs_inode.h"
17#include "xfs_trans.h"
18#include "xfs_log.h"
19#include "xfs_log_priv.h"
20#include "xfs_log_recover.h"
21#include "xfs_trans_priv.h"
22#include "xfs_alloc.h"
23#include "xfs_ialloc.h"
24#include "xfs_trace.h"
25#include "xfs_icache.h"
26#include "xfs_error.h"
27#include "xfs_buf_item.h"
28#include "xfs_ag.h"
29#include "xfs_quota.h"
30#include "xfs_reflink.h"
31
32#define BLK_AVG(blk1, blk2) ((blk1+blk2) >> 1)
33
34STATIC int
35xlog_find_zeroed(
36 struct xlog *,
37 xfs_daddr_t *);
38STATIC int
39xlog_clear_stale_blocks(
40 struct xlog *,
41 xfs_lsn_t);
42STATIC int
43xlog_do_recovery_pass(
44 struct xlog *, xfs_daddr_t, xfs_daddr_t, int, xfs_daddr_t *);
45
46/*
47 * Sector aligned buffer routines for buffer create/read/write/access
48 */
49
50/*
51 * Verify the log-relative block number and length in basic blocks are valid for
52 * an operation involving the given XFS log buffer. Returns true if the fields
53 * are valid, false otherwise.
54 */
55static inline bool
56xlog_verify_bno(
57 struct xlog *log,
58 xfs_daddr_t blk_no,
59 int bbcount)
60{
61 if (blk_no < 0 || blk_no >= log->l_logBBsize)
62 return false;
63 if (bbcount <= 0 || (blk_no + bbcount) > log->l_logBBsize)
64 return false;
65 return true;
66}
67
68/*
69 * Allocate a buffer to hold log data. The buffer needs to be able to map to
70 * a range of nbblks basic blocks at any valid offset within the log.
71 */
72static char *
73xlog_alloc_buffer(
74 struct xlog *log,
75 int nbblks)
76{
77 /*
78 * Pass log block 0 since we don't have an addr yet, buffer will be
79 * verified on read.
80 */
81 if (XFS_IS_CORRUPT(log->l_mp, !xlog_verify_bno(log, 0, nbblks))) {
82 xfs_warn(log->l_mp, "Invalid block length (0x%x) for buffer",
83 nbblks);
84 return NULL;
85 }
86
87 /*
88 * We do log I/O in units of log sectors (a power-of-2 multiple of the
89 * basic block size), so we round up the requested size to accommodate
90 * the basic blocks required for complete log sectors.
91 *
92 * In addition, the buffer may be used for a non-sector-aligned block
93 * offset, in which case an I/O of the requested size could extend
94 * beyond the end of the buffer. If the requested size is only 1 basic
95 * block it will never straddle a sector boundary, so this won't be an
96 * issue. Nor will this be a problem if the log I/O is done in basic
97 * blocks (sector size 1). But otherwise we extend the buffer by one
98 * extra log sector to ensure there's space to accommodate this
99 * possibility.
100 */
101 if (nbblks > 1 && log->l_sectBBsize > 1)
102 nbblks += log->l_sectBBsize;
103 nbblks = round_up(nbblks, log->l_sectBBsize);
104 return kvzalloc(BBTOB(nbblks), GFP_KERNEL | __GFP_RETRY_MAYFAIL);
105}
106
107/*
108 * Return the address of the start of the given block number's data
109 * in a log buffer. The buffer covers a log sector-aligned region.
110 */
111static inline unsigned int
112xlog_align(
113 struct xlog *log,
114 xfs_daddr_t blk_no)
115{
116 return BBTOB(blk_no & ((xfs_daddr_t)log->l_sectBBsize - 1));
117}
118
119static int
120xlog_do_io(
121 struct xlog *log,
122 xfs_daddr_t blk_no,
123 unsigned int nbblks,
124 char *data,
125 enum req_op op)
126{
127 int error;
128
129 if (XFS_IS_CORRUPT(log->l_mp, !xlog_verify_bno(log, blk_no, nbblks))) {
130 xfs_warn(log->l_mp,
131 "Invalid log block/length (0x%llx, 0x%x) for buffer",
132 blk_no, nbblks);
133 return -EFSCORRUPTED;
134 }
135
136 blk_no = round_down(blk_no, log->l_sectBBsize);
137 nbblks = round_up(nbblks, log->l_sectBBsize);
138 ASSERT(nbblks > 0);
139
140 error = xfs_rw_bdev(log->l_targ->bt_bdev, log->l_logBBstart + blk_no,
141 BBTOB(nbblks), data, op);
142 if (error && !xlog_is_shutdown(log)) {
143 xfs_alert(log->l_mp,
144 "log recovery %s I/O error at daddr 0x%llx len %d error %d",
145 op == REQ_OP_WRITE ? "write" : "read",
146 blk_no, nbblks, error);
147 }
148 return error;
149}
150
151STATIC int
152xlog_bread_noalign(
153 struct xlog *log,
154 xfs_daddr_t blk_no,
155 int nbblks,
156 char *data)
157{
158 return xlog_do_io(log, blk_no, nbblks, data, REQ_OP_READ);
159}
160
161STATIC int
162xlog_bread(
163 struct xlog *log,
164 xfs_daddr_t blk_no,
165 int nbblks,
166 char *data,
167 char **offset)
168{
169 int error;
170
171 error = xlog_do_io(log, blk_no, nbblks, data, REQ_OP_READ);
172 if (!error)
173 *offset = data + xlog_align(log, blk_no);
174 return error;
175}
176
177STATIC int
178xlog_bwrite(
179 struct xlog *log,
180 xfs_daddr_t blk_no,
181 int nbblks,
182 char *data)
183{
184 return xlog_do_io(log, blk_no, nbblks, data, REQ_OP_WRITE);
185}
186
187#ifdef DEBUG
188/*
189 * dump debug superblock and log record information
190 */
191STATIC void
192xlog_header_check_dump(
193 xfs_mount_t *mp,
194 xlog_rec_header_t *head)
195{
196 xfs_debug(mp, "%s: SB : uuid = %pU, fmt = %d",
197 __func__, &mp->m_sb.sb_uuid, XLOG_FMT);
198 xfs_debug(mp, " log : uuid = %pU, fmt = %d",
199 &head->h_fs_uuid, be32_to_cpu(head->h_fmt));
200}
201#else
202#define xlog_header_check_dump(mp, head)
203#endif
204
205/*
206 * check log record header for recovery
207 */
208STATIC int
209xlog_header_check_recover(
210 xfs_mount_t *mp,
211 xlog_rec_header_t *head)
212{
213 ASSERT(head->h_magicno == cpu_to_be32(XLOG_HEADER_MAGIC_NUM));
214
215 /*
216 * IRIX doesn't write the h_fmt field and leaves it zeroed
217 * (XLOG_FMT_UNKNOWN). This stops us from trying to recover
218 * a dirty log created in IRIX.
219 */
220 if (XFS_IS_CORRUPT(mp, head->h_fmt != cpu_to_be32(XLOG_FMT))) {
221 xfs_warn(mp,
222 "dirty log written in incompatible format - can't recover");
223 xlog_header_check_dump(mp, head);
224 return -EFSCORRUPTED;
225 }
226 if (XFS_IS_CORRUPT(mp, !uuid_equal(&mp->m_sb.sb_uuid,
227 &head->h_fs_uuid))) {
228 xfs_warn(mp,
229 "dirty log entry has mismatched uuid - can't recover");
230 xlog_header_check_dump(mp, head);
231 return -EFSCORRUPTED;
232 }
233 return 0;
234}
235
236/*
237 * read the head block of the log and check the header
238 */
239STATIC int
240xlog_header_check_mount(
241 xfs_mount_t *mp,
242 xlog_rec_header_t *head)
243{
244 ASSERT(head->h_magicno == cpu_to_be32(XLOG_HEADER_MAGIC_NUM));
245
246 if (uuid_is_null(&head->h_fs_uuid)) {
247 /*
248 * IRIX doesn't write the h_fs_uuid or h_fmt fields. If
249 * h_fs_uuid is null, we assume this log was last mounted
250 * by IRIX and continue.
251 */
252 xfs_warn(mp, "null uuid in log - IRIX style log");
253 } else if (XFS_IS_CORRUPT(mp, !uuid_equal(&mp->m_sb.sb_uuid,
254 &head->h_fs_uuid))) {
255 xfs_warn(mp, "log has mismatched uuid - can't recover");
256 xlog_header_check_dump(mp, head);
257 return -EFSCORRUPTED;
258 }
259 return 0;
260}
261
262/*
263 * This routine finds (to an approximation) the first block in the physical
264 * log which contains the given cycle. It uses a binary search algorithm.
265 * Note that the algorithm can not be perfect because the disk will not
266 * necessarily be perfect.
267 */
268STATIC int
269xlog_find_cycle_start(
270 struct xlog *log,
271 char *buffer,
272 xfs_daddr_t first_blk,
273 xfs_daddr_t *last_blk,
274 uint cycle)
275{
276 char *offset;
277 xfs_daddr_t mid_blk;
278 xfs_daddr_t end_blk;
279 uint mid_cycle;
280 int error;
281
282 end_blk = *last_blk;
283 mid_blk = BLK_AVG(first_blk, end_blk);
284 while (mid_blk != first_blk && mid_blk != end_blk) {
285 error = xlog_bread(log, mid_blk, 1, buffer, &offset);
286 if (error)
287 return error;
288 mid_cycle = xlog_get_cycle(offset);
289 if (mid_cycle == cycle)
290 end_blk = mid_blk; /* last_half_cycle == mid_cycle */
291 else
292 first_blk = mid_blk; /* first_half_cycle == mid_cycle */
293 mid_blk = BLK_AVG(first_blk, end_blk);
294 }
295 ASSERT((mid_blk == first_blk && mid_blk+1 == end_blk) ||
296 (mid_blk == end_blk && mid_blk-1 == first_blk));
297
298 *last_blk = end_blk;
299
300 return 0;
301}
302
303/*
304 * Check that a range of blocks does not contain stop_on_cycle_no.
305 * Fill in *new_blk with the block offset where such a block is
306 * found, or with -1 (an invalid block number) if there is no such
307 * block in the range. The scan needs to occur from front to back
308 * and the pointer into the region must be updated since a later
309 * routine will need to perform another test.
310 */
311STATIC int
312xlog_find_verify_cycle(
313 struct xlog *log,
314 xfs_daddr_t start_blk,
315 int nbblks,
316 uint stop_on_cycle_no,
317 xfs_daddr_t *new_blk)
318{
319 xfs_daddr_t i, j;
320 uint cycle;
321 char *buffer;
322 xfs_daddr_t bufblks;
323 char *buf = NULL;
324 int error = 0;
325
326 /*
327 * Greedily allocate a buffer big enough to handle the full
328 * range of basic blocks we'll be examining. If that fails,
329 * try a smaller size. We need to be able to read at least
330 * a log sector, or we're out of luck.
331 */
332 bufblks = roundup_pow_of_two(nbblks);
333 while (bufblks > log->l_logBBsize)
334 bufblks >>= 1;
335 while (!(buffer = xlog_alloc_buffer(log, bufblks))) {
336 bufblks >>= 1;
337 if (bufblks < log->l_sectBBsize)
338 return -ENOMEM;
339 }
340
341 for (i = start_blk; i < start_blk + nbblks; i += bufblks) {
342 int bcount;
343
344 bcount = min(bufblks, (start_blk + nbblks - i));
345
346 error = xlog_bread(log, i, bcount, buffer, &buf);
347 if (error)
348 goto out;
349
350 for (j = 0; j < bcount; j++) {
351 cycle = xlog_get_cycle(buf);
352 if (cycle == stop_on_cycle_no) {
353 *new_blk = i+j;
354 goto out;
355 }
356
357 buf += BBSIZE;
358 }
359 }
360
361 *new_blk = -1;
362
363out:
364 kvfree(buffer);
365 return error;
366}
367
368static inline int
369xlog_logrec_hblks(struct xlog *log, struct xlog_rec_header *rh)
370{
371 if (xfs_has_logv2(log->l_mp)) {
372 int h_size = be32_to_cpu(rh->h_size);
373
374 if ((be32_to_cpu(rh->h_version) & XLOG_VERSION_2) &&
375 h_size > XLOG_HEADER_CYCLE_SIZE)
376 return DIV_ROUND_UP(h_size, XLOG_HEADER_CYCLE_SIZE);
377 }
378 return 1;
379}
380
381/*
382 * Potentially backup over partial log record write.
383 *
384 * In the typical case, last_blk is the number of the block directly after
385 * a good log record. Therefore, we subtract one to get the block number
386 * of the last block in the given buffer. extra_bblks contains the number
387 * of blocks we would have read on a previous read. This happens when the
388 * last log record is split over the end of the physical log.
389 *
390 * extra_bblks is the number of blocks potentially verified on a previous
391 * call to this routine.
392 */
393STATIC int
394xlog_find_verify_log_record(
395 struct xlog *log,
396 xfs_daddr_t start_blk,
397 xfs_daddr_t *last_blk,
398 int extra_bblks)
399{
400 xfs_daddr_t i;
401 char *buffer;
402 char *offset = NULL;
403 xlog_rec_header_t *head = NULL;
404 int error = 0;
405 int smallmem = 0;
406 int num_blks = *last_blk - start_blk;
407 int xhdrs;
408
409 ASSERT(start_blk != 0 || *last_blk != start_blk);
410
411 buffer = xlog_alloc_buffer(log, num_blks);
412 if (!buffer) {
413 buffer = xlog_alloc_buffer(log, 1);
414 if (!buffer)
415 return -ENOMEM;
416 smallmem = 1;
417 } else {
418 error = xlog_bread(log, start_blk, num_blks, buffer, &offset);
419 if (error)
420 goto out;
421 offset += ((num_blks - 1) << BBSHIFT);
422 }
423
424 for (i = (*last_blk) - 1; i >= 0; i--) {
425 if (i < start_blk) {
426 /* valid log record not found */
427 xfs_warn(log->l_mp,
428 "Log inconsistent (didn't find previous header)");
429 ASSERT(0);
430 error = -EFSCORRUPTED;
431 goto out;
432 }
433
434 if (smallmem) {
435 error = xlog_bread(log, i, 1, buffer, &offset);
436 if (error)
437 goto out;
438 }
439
440 head = (xlog_rec_header_t *)offset;
441
442 if (head->h_magicno == cpu_to_be32(XLOG_HEADER_MAGIC_NUM))
443 break;
444
445 if (!smallmem)
446 offset -= BBSIZE;
447 }
448
449 /*
450 * We hit the beginning of the physical log & still no header. Return
451 * to caller. If caller can handle a return of -1, then this routine
452 * will be called again for the end of the physical log.
453 */
454 if (i == -1) {
455 error = 1;
456 goto out;
457 }
458
459 /*
460 * We have the final block of the good log (the first block
461 * of the log record _before_ the head. So we check the uuid.
462 */
463 if ((error = xlog_header_check_mount(log->l_mp, head)))
464 goto out;
465
466 /*
467 * We may have found a log record header before we expected one.
468 * last_blk will be the 1st block # with a given cycle #. We may end
469 * up reading an entire log record. In this case, we don't want to
470 * reset last_blk. Only when last_blk points in the middle of a log
471 * record do we update last_blk.
472 */
473 xhdrs = xlog_logrec_hblks(log, head);
474
475 if (*last_blk - i + extra_bblks !=
476 BTOBB(be32_to_cpu(head->h_len)) + xhdrs)
477 *last_blk = i;
478
479out:
480 kvfree(buffer);
481 return error;
482}
483
484/*
485 * Head is defined to be the point of the log where the next log write
486 * could go. This means that incomplete LR writes at the end are
487 * eliminated when calculating the head. We aren't guaranteed that previous
488 * LR have complete transactions. We only know that a cycle number of
489 * current cycle number -1 won't be present in the log if we start writing
490 * from our current block number.
491 *
492 * last_blk contains the block number of the first block with a given
493 * cycle number.
494 *
495 * Return: zero if normal, non-zero if error.
496 */
497STATIC int
498xlog_find_head(
499 struct xlog *log,
500 xfs_daddr_t *return_head_blk)
501{
502 char *buffer;
503 char *offset;
504 xfs_daddr_t new_blk, first_blk, start_blk, last_blk, head_blk;
505 int num_scan_bblks;
506 uint first_half_cycle, last_half_cycle;
507 uint stop_on_cycle;
508 int error, log_bbnum = log->l_logBBsize;
509
510 /* Is the end of the log device zeroed? */
511 error = xlog_find_zeroed(log, &first_blk);
512 if (error < 0) {
513 xfs_warn(log->l_mp, "empty log check failed");
514 return error;
515 }
516 if (error == 1) {
517 *return_head_blk = first_blk;
518
519 /* Is the whole lot zeroed? */
520 if (!first_blk) {
521 /* Linux XFS shouldn't generate totally zeroed logs -
522 * mkfs etc write a dummy unmount record to a fresh
523 * log so we can store the uuid in there
524 */
525 xfs_warn(log->l_mp, "totally zeroed log");
526 }
527
528 return 0;
529 }
530
531 first_blk = 0; /* get cycle # of 1st block */
532 buffer = xlog_alloc_buffer(log, 1);
533 if (!buffer)
534 return -ENOMEM;
535
536 error = xlog_bread(log, 0, 1, buffer, &offset);
537 if (error)
538 goto out_free_buffer;
539
540 first_half_cycle = xlog_get_cycle(offset);
541
542 last_blk = head_blk = log_bbnum - 1; /* get cycle # of last block */
543 error = xlog_bread(log, last_blk, 1, buffer, &offset);
544 if (error)
545 goto out_free_buffer;
546
547 last_half_cycle = xlog_get_cycle(offset);
548 ASSERT(last_half_cycle != 0);
549
550 /*
551 * If the 1st half cycle number is equal to the last half cycle number,
552 * then the entire log is stamped with the same cycle number. In this
553 * case, head_blk can't be set to zero (which makes sense). The below
554 * math doesn't work out properly with head_blk equal to zero. Instead,
555 * we set it to log_bbnum which is an invalid block number, but this
556 * value makes the math correct. If head_blk doesn't changed through
557 * all the tests below, *head_blk is set to zero at the very end rather
558 * than log_bbnum. In a sense, log_bbnum and zero are the same block
559 * in a circular file.
560 */
561 if (first_half_cycle == last_half_cycle) {
562 /*
563 * In this case we believe that the entire log should have
564 * cycle number last_half_cycle. We need to scan backwards
565 * from the end verifying that there are no holes still
566 * containing last_half_cycle - 1. If we find such a hole,
567 * then the start of that hole will be the new head. The
568 * simple case looks like
569 * x | x ... | x - 1 | x
570 * Another case that fits this picture would be
571 * x | x + 1 | x ... | x
572 * In this case the head really is somewhere at the end of the
573 * log, as one of the latest writes at the beginning was
574 * incomplete.
575 * One more case is
576 * x | x + 1 | x ... | x - 1 | x
577 * This is really the combination of the above two cases, and
578 * the head has to end up at the start of the x-1 hole at the
579 * end of the log.
580 *
581 * In the 256k log case, we will read from the beginning to the
582 * end of the log and search for cycle numbers equal to x-1.
583 * We don't worry about the x+1 blocks that we encounter,
584 * because we know that they cannot be the head since the log
585 * started with x.
586 */
587 head_blk = log_bbnum;
588 stop_on_cycle = last_half_cycle - 1;
589 } else {
590 /*
591 * In this case we want to find the first block with cycle
592 * number matching last_half_cycle. We expect the log to be
593 * some variation on
594 * x + 1 ... | x ... | x
595 * The first block with cycle number x (last_half_cycle) will
596 * be where the new head belongs. First we do a binary search
597 * for the first occurrence of last_half_cycle. The binary
598 * search may not be totally accurate, so then we scan back
599 * from there looking for occurrences of last_half_cycle before
600 * us. If that backwards scan wraps around the beginning of
601 * the log, then we look for occurrences of last_half_cycle - 1
602 * at the end of the log. The cases we're looking for look
603 * like
604 * v binary search stopped here
605 * x + 1 ... | x | x + 1 | x ... | x
606 * ^ but we want to locate this spot
607 * or
608 * <---------> less than scan distance
609 * x + 1 ... | x ... | x - 1 | x
610 * ^ we want to locate this spot
611 */
612 stop_on_cycle = last_half_cycle;
613 error = xlog_find_cycle_start(log, buffer, first_blk, &head_blk,
614 last_half_cycle);
615 if (error)
616 goto out_free_buffer;
617 }
618
619 /*
620 * Now validate the answer. Scan back some number of maximum possible
621 * blocks and make sure each one has the expected cycle number. The
622 * maximum is determined by the total possible amount of buffering
623 * in the in-core log. The following number can be made tighter if
624 * we actually look at the block size of the filesystem.
625 */
626 num_scan_bblks = min_t(int, log_bbnum, XLOG_TOTAL_REC_SHIFT(log));
627 if (head_blk >= num_scan_bblks) {
628 /*
629 * We are guaranteed that the entire check can be performed
630 * in one buffer.
631 */
632 start_blk = head_blk - num_scan_bblks;
633 if ((error = xlog_find_verify_cycle(log,
634 start_blk, num_scan_bblks,
635 stop_on_cycle, &new_blk)))
636 goto out_free_buffer;
637 if (new_blk != -1)
638 head_blk = new_blk;
639 } else { /* need to read 2 parts of log */
640 /*
641 * We are going to scan backwards in the log in two parts.
642 * First we scan the physical end of the log. In this part
643 * of the log, we are looking for blocks with cycle number
644 * last_half_cycle - 1.
645 * If we find one, then we know that the log starts there, as
646 * we've found a hole that didn't get written in going around
647 * the end of the physical log. The simple case for this is
648 * x + 1 ... | x ... | x - 1 | x
649 * <---------> less than scan distance
650 * If all of the blocks at the end of the log have cycle number
651 * last_half_cycle, then we check the blocks at the start of
652 * the log looking for occurrences of last_half_cycle. If we
653 * find one, then our current estimate for the location of the
654 * first occurrence of last_half_cycle is wrong and we move
655 * back to the hole we've found. This case looks like
656 * x + 1 ... | x | x + 1 | x ...
657 * ^ binary search stopped here
658 * Another case we need to handle that only occurs in 256k
659 * logs is
660 * x + 1 ... | x ... | x+1 | x ...
661 * ^ binary search stops here
662 * In a 256k log, the scan at the end of the log will see the
663 * x + 1 blocks. We need to skip past those since that is
664 * certainly not the head of the log. By searching for
665 * last_half_cycle-1 we accomplish that.
666 */
667 ASSERT(head_blk <= INT_MAX &&
668 (xfs_daddr_t) num_scan_bblks >= head_blk);
669 start_blk = log_bbnum - (num_scan_bblks - head_blk);
670 if ((error = xlog_find_verify_cycle(log, start_blk,
671 num_scan_bblks - (int)head_blk,
672 (stop_on_cycle - 1), &new_blk)))
673 goto out_free_buffer;
674 if (new_blk != -1) {
675 head_blk = new_blk;
676 goto validate_head;
677 }
678
679 /*
680 * Scan beginning of log now. The last part of the physical
681 * log is good. This scan needs to verify that it doesn't find
682 * the last_half_cycle.
683 */
684 start_blk = 0;
685 ASSERT(head_blk <= INT_MAX);
686 if ((error = xlog_find_verify_cycle(log,
687 start_blk, (int)head_blk,
688 stop_on_cycle, &new_blk)))
689 goto out_free_buffer;
690 if (new_blk != -1)
691 head_blk = new_blk;
692 }
693
694validate_head:
695 /*
696 * Now we need to make sure head_blk is not pointing to a block in
697 * the middle of a log record.
698 */
699 num_scan_bblks = XLOG_REC_SHIFT(log);
700 if (head_blk >= num_scan_bblks) {
701 start_blk = head_blk - num_scan_bblks; /* don't read head_blk */
702
703 /* start ptr at last block ptr before head_blk */
704 error = xlog_find_verify_log_record(log, start_blk, &head_blk, 0);
705 if (error == 1)
706 error = -EIO;
707 if (error)
708 goto out_free_buffer;
709 } else {
710 start_blk = 0;
711 ASSERT(head_blk <= INT_MAX);
712 error = xlog_find_verify_log_record(log, start_blk, &head_blk, 0);
713 if (error < 0)
714 goto out_free_buffer;
715 if (error == 1) {
716 /* We hit the beginning of the log during our search */
717 start_blk = log_bbnum - (num_scan_bblks - head_blk);
718 new_blk = log_bbnum;
719 ASSERT(start_blk <= INT_MAX &&
720 (xfs_daddr_t) log_bbnum-start_blk >= 0);
721 ASSERT(head_blk <= INT_MAX);
722 error = xlog_find_verify_log_record(log, start_blk,
723 &new_blk, (int)head_blk);
724 if (error == 1)
725 error = -EIO;
726 if (error)
727 goto out_free_buffer;
728 if (new_blk != log_bbnum)
729 head_blk = new_blk;
730 } else if (error)
731 goto out_free_buffer;
732 }
733
734 kvfree(buffer);
735 if (head_blk == log_bbnum)
736 *return_head_blk = 0;
737 else
738 *return_head_blk = head_blk;
739 /*
740 * When returning here, we have a good block number. Bad block
741 * means that during a previous crash, we didn't have a clean break
742 * from cycle number N to cycle number N-1. In this case, we need
743 * to find the first block with cycle number N-1.
744 */
745 return 0;
746
747out_free_buffer:
748 kvfree(buffer);
749 if (error)
750 xfs_warn(log->l_mp, "failed to find log head");
751 return error;
752}
753
754/*
755 * Seek backwards in the log for log record headers.
756 *
757 * Given a starting log block, walk backwards until we find the provided number
758 * of records or hit the provided tail block. The return value is the number of
759 * records encountered or a negative error code. The log block and buffer
760 * pointer of the last record seen are returned in rblk and rhead respectively.
761 */
762STATIC int
763xlog_rseek_logrec_hdr(
764 struct xlog *log,
765 xfs_daddr_t head_blk,
766 xfs_daddr_t tail_blk,
767 int count,
768 char *buffer,
769 xfs_daddr_t *rblk,
770 struct xlog_rec_header **rhead,
771 bool *wrapped)
772{
773 int i;
774 int error;
775 int found = 0;
776 char *offset = NULL;
777 xfs_daddr_t end_blk;
778
779 *wrapped = false;
780
781 /*
782 * Walk backwards from the head block until we hit the tail or the first
783 * block in the log.
784 */
785 end_blk = head_blk > tail_blk ? tail_blk : 0;
786 for (i = (int) head_blk - 1; i >= end_blk; i--) {
787 error = xlog_bread(log, i, 1, buffer, &offset);
788 if (error)
789 goto out_error;
790
791 if (*(__be32 *) offset == cpu_to_be32(XLOG_HEADER_MAGIC_NUM)) {
792 *rblk = i;
793 *rhead = (struct xlog_rec_header *) offset;
794 if (++found == count)
795 break;
796 }
797 }
798
799 /*
800 * If we haven't hit the tail block or the log record header count,
801 * start looking again from the end of the physical log. Note that
802 * callers can pass head == tail if the tail is not yet known.
803 */
804 if (tail_blk >= head_blk && found != count) {
805 for (i = log->l_logBBsize - 1; i >= (int) tail_blk; i--) {
806 error = xlog_bread(log, i, 1, buffer, &offset);
807 if (error)
808 goto out_error;
809
810 if (*(__be32 *)offset ==
811 cpu_to_be32(XLOG_HEADER_MAGIC_NUM)) {
812 *wrapped = true;
813 *rblk = i;
814 *rhead = (struct xlog_rec_header *) offset;
815 if (++found == count)
816 break;
817 }
818 }
819 }
820
821 return found;
822
823out_error:
824 return error;
825}
826
827/*
828 * Seek forward in the log for log record headers.
829 *
830 * Given head and tail blocks, walk forward from the tail block until we find
831 * the provided number of records or hit the head block. The return value is the
832 * number of records encountered or a negative error code. The log block and
833 * buffer pointer of the last record seen are returned in rblk and rhead
834 * respectively.
835 */
836STATIC int
837xlog_seek_logrec_hdr(
838 struct xlog *log,
839 xfs_daddr_t head_blk,
840 xfs_daddr_t tail_blk,
841 int count,
842 char *buffer,
843 xfs_daddr_t *rblk,
844 struct xlog_rec_header **rhead,
845 bool *wrapped)
846{
847 int i;
848 int error;
849 int found = 0;
850 char *offset = NULL;
851 xfs_daddr_t end_blk;
852
853 *wrapped = false;
854
855 /*
856 * Walk forward from the tail block until we hit the head or the last
857 * block in the log.
858 */
859 end_blk = head_blk > tail_blk ? head_blk : log->l_logBBsize - 1;
860 for (i = (int) tail_blk; i <= end_blk; i++) {
861 error = xlog_bread(log, i, 1, buffer, &offset);
862 if (error)
863 goto out_error;
864
865 if (*(__be32 *) offset == cpu_to_be32(XLOG_HEADER_MAGIC_NUM)) {
866 *rblk = i;
867 *rhead = (struct xlog_rec_header *) offset;
868 if (++found == count)
869 break;
870 }
871 }
872
873 /*
874 * If we haven't hit the head block or the log record header count,
875 * start looking again from the start of the physical log.
876 */
877 if (tail_blk > head_blk && found != count) {
878 for (i = 0; i < (int) head_blk; i++) {
879 error = xlog_bread(log, i, 1, buffer, &offset);
880 if (error)
881 goto out_error;
882
883 if (*(__be32 *)offset ==
884 cpu_to_be32(XLOG_HEADER_MAGIC_NUM)) {
885 *wrapped = true;
886 *rblk = i;
887 *rhead = (struct xlog_rec_header *) offset;
888 if (++found == count)
889 break;
890 }
891 }
892 }
893
894 return found;
895
896out_error:
897 return error;
898}
899
900/*
901 * Calculate distance from head to tail (i.e., unused space in the log).
902 */
903static inline int
904xlog_tail_distance(
905 struct xlog *log,
906 xfs_daddr_t head_blk,
907 xfs_daddr_t tail_blk)
908{
909 if (head_blk < tail_blk)
910 return tail_blk - head_blk;
911
912 return tail_blk + (log->l_logBBsize - head_blk);
913}
914
915/*
916 * Verify the log tail. This is particularly important when torn or incomplete
917 * writes have been detected near the front of the log and the head has been
918 * walked back accordingly.
919 *
920 * We also have to handle the case where the tail was pinned and the head
921 * blocked behind the tail right before a crash. If the tail had been pushed
922 * immediately prior to the crash and the subsequent checkpoint was only
923 * partially written, it's possible it overwrote the last referenced tail in the
924 * log with garbage. This is not a coherency problem because the tail must have
925 * been pushed before it can be overwritten, but appears as log corruption to
926 * recovery because we have no way to know the tail was updated if the
927 * subsequent checkpoint didn't write successfully.
928 *
929 * Therefore, CRC check the log from tail to head. If a failure occurs and the
930 * offending record is within max iclog bufs from the head, walk the tail
931 * forward and retry until a valid tail is found or corruption is detected out
932 * of the range of a possible overwrite.
933 */
934STATIC int
935xlog_verify_tail(
936 struct xlog *log,
937 xfs_daddr_t head_blk,
938 xfs_daddr_t *tail_blk,
939 int hsize)
940{
941 struct xlog_rec_header *thead;
942 char *buffer;
943 xfs_daddr_t first_bad;
944 int error = 0;
945 bool wrapped;
946 xfs_daddr_t tmp_tail;
947 xfs_daddr_t orig_tail = *tail_blk;
948
949 buffer = xlog_alloc_buffer(log, 1);
950 if (!buffer)
951 return -ENOMEM;
952
953 /*
954 * Make sure the tail points to a record (returns positive count on
955 * success).
956 */
957 error = xlog_seek_logrec_hdr(log, head_blk, *tail_blk, 1, buffer,
958 &tmp_tail, &thead, &wrapped);
959 if (error < 0)
960 goto out;
961 if (*tail_blk != tmp_tail)
962 *tail_blk = tmp_tail;
963
964 /*
965 * Run a CRC check from the tail to the head. We can't just check
966 * MAX_ICLOGS records past the tail because the tail may point to stale
967 * blocks cleared during the search for the head/tail. These blocks are
968 * overwritten with zero-length records and thus record count is not a
969 * reliable indicator of the iclog state before a crash.
970 */
971 first_bad = 0;
972 error = xlog_do_recovery_pass(log, head_blk, *tail_blk,
973 XLOG_RECOVER_CRCPASS, &first_bad);
974 while ((error == -EFSBADCRC || error == -EFSCORRUPTED) && first_bad) {
975 int tail_distance;
976
977 /*
978 * Is corruption within range of the head? If so, retry from
979 * the next record. Otherwise return an error.
980 */
981 tail_distance = xlog_tail_distance(log, head_blk, first_bad);
982 if (tail_distance > BTOBB(XLOG_MAX_ICLOGS * hsize))
983 break;
984
985 /* skip to the next record; returns positive count on success */
986 error = xlog_seek_logrec_hdr(log, head_blk, first_bad, 2,
987 buffer, &tmp_tail, &thead, &wrapped);
988 if (error < 0)
989 goto out;
990
991 *tail_blk = tmp_tail;
992 first_bad = 0;
993 error = xlog_do_recovery_pass(log, head_blk, *tail_blk,
994 XLOG_RECOVER_CRCPASS, &first_bad);
995 }
996
997 if (!error && *tail_blk != orig_tail)
998 xfs_warn(log->l_mp,
999 "Tail block (0x%llx) overwrite detected. Updated to 0x%llx",
1000 orig_tail, *tail_blk);
1001out:
1002 kvfree(buffer);
1003 return error;
1004}
1005
1006/*
1007 * Detect and trim torn writes from the head of the log.
1008 *
1009 * Storage without sector atomicity guarantees can result in torn writes in the
1010 * log in the event of a crash. Our only means to detect this scenario is via
1011 * CRC verification. While we can't always be certain that CRC verification
1012 * failure is due to a torn write vs. an unrelated corruption, we do know that
1013 * only a certain number (XLOG_MAX_ICLOGS) of log records can be written out at
1014 * one time. Therefore, CRC verify up to XLOG_MAX_ICLOGS records at the head of
1015 * the log and treat failures in this range as torn writes as a matter of
1016 * policy. In the event of CRC failure, the head is walked back to the last good
1017 * record in the log and the tail is updated from that record and verified.
1018 */
1019STATIC int
1020xlog_verify_head(
1021 struct xlog *log,
1022 xfs_daddr_t *head_blk, /* in/out: unverified head */
1023 xfs_daddr_t *tail_blk, /* out: tail block */
1024 char *buffer,
1025 xfs_daddr_t *rhead_blk, /* start blk of last record */
1026 struct xlog_rec_header **rhead, /* ptr to last record */
1027 bool *wrapped) /* last rec. wraps phys. log */
1028{
1029 struct xlog_rec_header *tmp_rhead;
1030 char *tmp_buffer;
1031 xfs_daddr_t first_bad;
1032 xfs_daddr_t tmp_rhead_blk;
1033 int found;
1034 int error;
1035 bool tmp_wrapped;
1036
1037 /*
1038 * Check the head of the log for torn writes. Search backwards from the
1039 * head until we hit the tail or the maximum number of log record I/Os
1040 * that could have been in flight at one time. Use a temporary buffer so
1041 * we don't trash the rhead/buffer pointers from the caller.
1042 */
1043 tmp_buffer = xlog_alloc_buffer(log, 1);
1044 if (!tmp_buffer)
1045 return -ENOMEM;
1046 error = xlog_rseek_logrec_hdr(log, *head_blk, *tail_blk,
1047 XLOG_MAX_ICLOGS, tmp_buffer,
1048 &tmp_rhead_blk, &tmp_rhead, &tmp_wrapped);
1049 kvfree(tmp_buffer);
1050 if (error < 0)
1051 return error;
1052
1053 /*
1054 * Now run a CRC verification pass over the records starting at the
1055 * block found above to the current head. If a CRC failure occurs, the
1056 * log block of the first bad record is saved in first_bad.
1057 */
1058 error = xlog_do_recovery_pass(log, *head_blk, tmp_rhead_blk,
1059 XLOG_RECOVER_CRCPASS, &first_bad);
1060 if ((error == -EFSBADCRC || error == -EFSCORRUPTED) && first_bad) {
1061 /*
1062 * We've hit a potential torn write. Reset the error and warn
1063 * about it.
1064 */
1065 error = 0;
1066 xfs_warn(log->l_mp,
1067"Torn write (CRC failure) detected at log block 0x%llx. Truncating head block from 0x%llx.",
1068 first_bad, *head_blk);
1069
1070 /*
1071 * Get the header block and buffer pointer for the last good
1072 * record before the bad record.
1073 *
1074 * Note that xlog_find_tail() clears the blocks at the new head
1075 * (i.e., the records with invalid CRC) if the cycle number
1076 * matches the current cycle.
1077 */
1078 found = xlog_rseek_logrec_hdr(log, first_bad, *tail_blk, 1,
1079 buffer, rhead_blk, rhead, wrapped);
1080 if (found < 0)
1081 return found;
1082 if (found == 0) /* XXX: right thing to do here? */
1083 return -EIO;
1084
1085 /*
1086 * Reset the head block to the starting block of the first bad
1087 * log record and set the tail block based on the last good
1088 * record.
1089 *
1090 * Bail out if the updated head/tail match as this indicates
1091 * possible corruption outside of the acceptable
1092 * (XLOG_MAX_ICLOGS) range. This is a job for xfs_repair...
1093 */
1094 *head_blk = first_bad;
1095 *tail_blk = BLOCK_LSN(be64_to_cpu((*rhead)->h_tail_lsn));
1096 if (*head_blk == *tail_blk) {
1097 ASSERT(0);
1098 return 0;
1099 }
1100 }
1101 if (error)
1102 return error;
1103
1104 return xlog_verify_tail(log, *head_blk, tail_blk,
1105 be32_to_cpu((*rhead)->h_size));
1106}
1107
1108/*
1109 * We need to make sure we handle log wrapping properly, so we can't use the
1110 * calculated logbno directly. Make sure it wraps to the correct bno inside the
1111 * log.
1112 *
1113 * The log is limited to 32 bit sizes, so we use the appropriate modulus
1114 * operation here and cast it back to a 64 bit daddr on return.
1115 */
1116static inline xfs_daddr_t
1117xlog_wrap_logbno(
1118 struct xlog *log,
1119 xfs_daddr_t bno)
1120{
1121 int mod;
1122
1123 div_s64_rem(bno, log->l_logBBsize, &mod);
1124 return mod;
1125}
1126
1127/*
1128 * Check whether the head of the log points to an unmount record. In other
1129 * words, determine whether the log is clean. If so, update the in-core state
1130 * appropriately.
1131 */
1132static int
1133xlog_check_unmount_rec(
1134 struct xlog *log,
1135 xfs_daddr_t *head_blk,
1136 xfs_daddr_t *tail_blk,
1137 struct xlog_rec_header *rhead,
1138 xfs_daddr_t rhead_blk,
1139 char *buffer,
1140 bool *clean)
1141{
1142 struct xlog_op_header *op_head;
1143 xfs_daddr_t umount_data_blk;
1144 xfs_daddr_t after_umount_blk;
1145 int hblks;
1146 int error;
1147 char *offset;
1148
1149 *clean = false;
1150
1151 /*
1152 * Look for unmount record. If we find it, then we know there was a
1153 * clean unmount. Since 'i' could be the last block in the physical
1154 * log, we convert to a log block before comparing to the head_blk.
1155 *
1156 * Save the current tail lsn to use to pass to xlog_clear_stale_blocks()
1157 * below. We won't want to clear the unmount record if there is one, so
1158 * we pass the lsn of the unmount record rather than the block after it.
1159 */
1160 hblks = xlog_logrec_hblks(log, rhead);
1161 after_umount_blk = xlog_wrap_logbno(log,
1162 rhead_blk + hblks + BTOBB(be32_to_cpu(rhead->h_len)));
1163
1164 if (*head_blk == after_umount_blk &&
1165 be32_to_cpu(rhead->h_num_logops) == 1) {
1166 umount_data_blk = xlog_wrap_logbno(log, rhead_blk + hblks);
1167 error = xlog_bread(log, umount_data_blk, 1, buffer, &offset);
1168 if (error)
1169 return error;
1170
1171 op_head = (struct xlog_op_header *)offset;
1172 if (op_head->oh_flags & XLOG_UNMOUNT_TRANS) {
1173 /*
1174 * Set tail and last sync so that newly written log
1175 * records will point recovery to after the current
1176 * unmount record.
1177 */
1178 xlog_assign_atomic_lsn(&log->l_tail_lsn,
1179 log->l_curr_cycle, after_umount_blk);
1180 xlog_assign_atomic_lsn(&log->l_last_sync_lsn,
1181 log->l_curr_cycle, after_umount_blk);
1182 *tail_blk = after_umount_blk;
1183
1184 *clean = true;
1185 }
1186 }
1187
1188 return 0;
1189}
1190
1191static void
1192xlog_set_state(
1193 struct xlog *log,
1194 xfs_daddr_t head_blk,
1195 struct xlog_rec_header *rhead,
1196 xfs_daddr_t rhead_blk,
1197 bool bump_cycle)
1198{
1199 /*
1200 * Reset log values according to the state of the log when we
1201 * crashed. In the case where head_blk == 0, we bump curr_cycle
1202 * one because the next write starts a new cycle rather than
1203 * continuing the cycle of the last good log record. At this
1204 * point we have guaranteed that all partial log records have been
1205 * accounted for. Therefore, we know that the last good log record
1206 * written was complete and ended exactly on the end boundary
1207 * of the physical log.
1208 */
1209 log->l_prev_block = rhead_blk;
1210 log->l_curr_block = (int)head_blk;
1211 log->l_curr_cycle = be32_to_cpu(rhead->h_cycle);
1212 if (bump_cycle)
1213 log->l_curr_cycle++;
1214 atomic64_set(&log->l_tail_lsn, be64_to_cpu(rhead->h_tail_lsn));
1215 atomic64_set(&log->l_last_sync_lsn, be64_to_cpu(rhead->h_lsn));
1216 xlog_assign_grant_head(&log->l_reserve_head.grant, log->l_curr_cycle,
1217 BBTOB(log->l_curr_block));
1218 xlog_assign_grant_head(&log->l_write_head.grant, log->l_curr_cycle,
1219 BBTOB(log->l_curr_block));
1220}
1221
1222/*
1223 * Find the sync block number or the tail of the log.
1224 *
1225 * This will be the block number of the last record to have its
1226 * associated buffers synced to disk. Every log record header has
1227 * a sync lsn embedded in it. LSNs hold block numbers, so it is easy
1228 * to get a sync block number. The only concern is to figure out which
1229 * log record header to believe.
1230 *
1231 * The following algorithm uses the log record header with the largest
1232 * lsn. The entire log record does not need to be valid. We only care
1233 * that the header is valid.
1234 *
1235 * We could speed up search by using current head_blk buffer, but it is not
1236 * available.
1237 */
1238STATIC int
1239xlog_find_tail(
1240 struct xlog *log,
1241 xfs_daddr_t *head_blk,
1242 xfs_daddr_t *tail_blk)
1243{
1244 xlog_rec_header_t *rhead;
1245 char *offset = NULL;
1246 char *buffer;
1247 int error;
1248 xfs_daddr_t rhead_blk;
1249 xfs_lsn_t tail_lsn;
1250 bool wrapped = false;
1251 bool clean = false;
1252
1253 /*
1254 * Find previous log record
1255 */
1256 if ((error = xlog_find_head(log, head_blk)))
1257 return error;
1258 ASSERT(*head_blk < INT_MAX);
1259
1260 buffer = xlog_alloc_buffer(log, 1);
1261 if (!buffer)
1262 return -ENOMEM;
1263 if (*head_blk == 0) { /* special case */
1264 error = xlog_bread(log, 0, 1, buffer, &offset);
1265 if (error)
1266 goto done;
1267
1268 if (xlog_get_cycle(offset) == 0) {
1269 *tail_blk = 0;
1270 /* leave all other log inited values alone */
1271 goto done;
1272 }
1273 }
1274
1275 /*
1276 * Search backwards through the log looking for the log record header
1277 * block. This wraps all the way back around to the head so something is
1278 * seriously wrong if we can't find it.
1279 */
1280 error = xlog_rseek_logrec_hdr(log, *head_blk, *head_blk, 1, buffer,
1281 &rhead_blk, &rhead, &wrapped);
1282 if (error < 0)
1283 goto done;
1284 if (!error) {
1285 xfs_warn(log->l_mp, "%s: couldn't find sync record", __func__);
1286 error = -EFSCORRUPTED;
1287 goto done;
1288 }
1289 *tail_blk = BLOCK_LSN(be64_to_cpu(rhead->h_tail_lsn));
1290
1291 /*
1292 * Set the log state based on the current head record.
1293 */
1294 xlog_set_state(log, *head_blk, rhead, rhead_blk, wrapped);
1295 tail_lsn = atomic64_read(&log->l_tail_lsn);
1296
1297 /*
1298 * Look for an unmount record at the head of the log. This sets the log
1299 * state to determine whether recovery is necessary.
1300 */
1301 error = xlog_check_unmount_rec(log, head_blk, tail_blk, rhead,
1302 rhead_blk, buffer, &clean);
1303 if (error)
1304 goto done;
1305
1306 /*
1307 * Verify the log head if the log is not clean (e.g., we have anything
1308 * but an unmount record at the head). This uses CRC verification to
1309 * detect and trim torn writes. If discovered, CRC failures are
1310 * considered torn writes and the log head is trimmed accordingly.
1311 *
1312 * Note that we can only run CRC verification when the log is dirty
1313 * because there's no guarantee that the log data behind an unmount
1314 * record is compatible with the current architecture.
1315 */
1316 if (!clean) {
1317 xfs_daddr_t orig_head = *head_blk;
1318
1319 error = xlog_verify_head(log, head_blk, tail_blk, buffer,
1320 &rhead_blk, &rhead, &wrapped);
1321 if (error)
1322 goto done;
1323
1324 /* update in-core state again if the head changed */
1325 if (*head_blk != orig_head) {
1326 xlog_set_state(log, *head_blk, rhead, rhead_blk,
1327 wrapped);
1328 tail_lsn = atomic64_read(&log->l_tail_lsn);
1329 error = xlog_check_unmount_rec(log, head_blk, tail_blk,
1330 rhead, rhead_blk, buffer,
1331 &clean);
1332 if (error)
1333 goto done;
1334 }
1335 }
1336
1337 /*
1338 * Note that the unmount was clean. If the unmount was not clean, we
1339 * need to know this to rebuild the superblock counters from the perag
1340 * headers if we have a filesystem using non-persistent counters.
1341 */
1342 if (clean)
1343 set_bit(XFS_OPSTATE_CLEAN, &log->l_mp->m_opstate);
1344
1345 /*
1346 * Make sure that there are no blocks in front of the head
1347 * with the same cycle number as the head. This can happen
1348 * because we allow multiple outstanding log writes concurrently,
1349 * and the later writes might make it out before earlier ones.
1350 *
1351 * We use the lsn from before modifying it so that we'll never
1352 * overwrite the unmount record after a clean unmount.
1353 *
1354 * Do this only if we are going to recover the filesystem
1355 *
1356 * NOTE: This used to say "if (!readonly)"
1357 * However on Linux, we can & do recover a read-only filesystem.
1358 * We only skip recovery if NORECOVERY is specified on mount,
1359 * in which case we would not be here.
1360 *
1361 * But... if the -device- itself is readonly, just skip this.
1362 * We can't recover this device anyway, so it won't matter.
1363 */
1364 if (!xfs_readonly_buftarg(log->l_targ))
1365 error = xlog_clear_stale_blocks(log, tail_lsn);
1366
1367done:
1368 kvfree(buffer);
1369
1370 if (error)
1371 xfs_warn(log->l_mp, "failed to locate log tail");
1372 return error;
1373}
1374
1375/*
1376 * Is the log zeroed at all?
1377 *
1378 * The last binary search should be changed to perform an X block read
1379 * once X becomes small enough. You can then search linearly through
1380 * the X blocks. This will cut down on the number of reads we need to do.
1381 *
1382 * If the log is partially zeroed, this routine will pass back the blkno
1383 * of the first block with cycle number 0. It won't have a complete LR
1384 * preceding it.
1385 *
1386 * Return:
1387 * 0 => the log is completely written to
1388 * 1 => use *blk_no as the first block of the log
1389 * <0 => error has occurred
1390 */
1391STATIC int
1392xlog_find_zeroed(
1393 struct xlog *log,
1394 xfs_daddr_t *blk_no)
1395{
1396 char *buffer;
1397 char *offset;
1398 uint first_cycle, last_cycle;
1399 xfs_daddr_t new_blk, last_blk, start_blk;
1400 xfs_daddr_t num_scan_bblks;
1401 int error, log_bbnum = log->l_logBBsize;
1402 int ret = 1;
1403
1404 *blk_no = 0;
1405
1406 /* check totally zeroed log */
1407 buffer = xlog_alloc_buffer(log, 1);
1408 if (!buffer)
1409 return -ENOMEM;
1410 error = xlog_bread(log, 0, 1, buffer, &offset);
1411 if (error)
1412 goto out_free_buffer;
1413
1414 first_cycle = xlog_get_cycle(offset);
1415 if (first_cycle == 0) { /* completely zeroed log */
1416 *blk_no = 0;
1417 goto out_free_buffer;
1418 }
1419
1420 /* check partially zeroed log */
1421 error = xlog_bread(log, log_bbnum-1, 1, buffer, &offset);
1422 if (error)
1423 goto out_free_buffer;
1424
1425 last_cycle = xlog_get_cycle(offset);
1426 if (last_cycle != 0) { /* log completely written to */
1427 ret = 0;
1428 goto out_free_buffer;
1429 }
1430
1431 /* we have a partially zeroed log */
1432 last_blk = log_bbnum-1;
1433 error = xlog_find_cycle_start(log, buffer, 0, &last_blk, 0);
1434 if (error)
1435 goto out_free_buffer;
1436
1437 /*
1438 * Validate the answer. Because there is no way to guarantee that
1439 * the entire log is made up of log records which are the same size,
1440 * we scan over the defined maximum blocks. At this point, the maximum
1441 * is not chosen to mean anything special. XXXmiken
1442 */
1443 num_scan_bblks = XLOG_TOTAL_REC_SHIFT(log);
1444 ASSERT(num_scan_bblks <= INT_MAX);
1445
1446 if (last_blk < num_scan_bblks)
1447 num_scan_bblks = last_blk;
1448 start_blk = last_blk - num_scan_bblks;
1449
1450 /*
1451 * We search for any instances of cycle number 0 that occur before
1452 * our current estimate of the head. What we're trying to detect is
1453 * 1 ... | 0 | 1 | 0...
1454 * ^ binary search ends here
1455 */
1456 if ((error = xlog_find_verify_cycle(log, start_blk,
1457 (int)num_scan_bblks, 0, &new_blk)))
1458 goto out_free_buffer;
1459 if (new_blk != -1)
1460 last_blk = new_blk;
1461
1462 /*
1463 * Potentially backup over partial log record write. We don't need
1464 * to search the end of the log because we know it is zero.
1465 */
1466 error = xlog_find_verify_log_record(log, start_blk, &last_blk, 0);
1467 if (error == 1)
1468 error = -EIO;
1469 if (error)
1470 goto out_free_buffer;
1471
1472 *blk_no = last_blk;
1473out_free_buffer:
1474 kvfree(buffer);
1475 if (error)
1476 return error;
1477 return ret;
1478}
1479
1480/*
1481 * These are simple subroutines used by xlog_clear_stale_blocks() below
1482 * to initialize a buffer full of empty log record headers and write
1483 * them into the log.
1484 */
1485STATIC void
1486xlog_add_record(
1487 struct xlog *log,
1488 char *buf,
1489 int cycle,
1490 int block,
1491 int tail_cycle,
1492 int tail_block)
1493{
1494 xlog_rec_header_t *recp = (xlog_rec_header_t *)buf;
1495
1496 memset(buf, 0, BBSIZE);
1497 recp->h_magicno = cpu_to_be32(XLOG_HEADER_MAGIC_NUM);
1498 recp->h_cycle = cpu_to_be32(cycle);
1499 recp->h_version = cpu_to_be32(
1500 xfs_has_logv2(log->l_mp) ? 2 : 1);
1501 recp->h_lsn = cpu_to_be64(xlog_assign_lsn(cycle, block));
1502 recp->h_tail_lsn = cpu_to_be64(xlog_assign_lsn(tail_cycle, tail_block));
1503 recp->h_fmt = cpu_to_be32(XLOG_FMT);
1504 memcpy(&recp->h_fs_uuid, &log->l_mp->m_sb.sb_uuid, sizeof(uuid_t));
1505}
1506
1507STATIC int
1508xlog_write_log_records(
1509 struct xlog *log,
1510 int cycle,
1511 int start_block,
1512 int blocks,
1513 int tail_cycle,
1514 int tail_block)
1515{
1516 char *offset;
1517 char *buffer;
1518 int balign, ealign;
1519 int sectbb = log->l_sectBBsize;
1520 int end_block = start_block + blocks;
1521 int bufblks;
1522 int error = 0;
1523 int i, j = 0;
1524
1525 /*
1526 * Greedily allocate a buffer big enough to handle the full
1527 * range of basic blocks to be written. If that fails, try
1528 * a smaller size. We need to be able to write at least a
1529 * log sector, or we're out of luck.
1530 */
1531 bufblks = roundup_pow_of_two(blocks);
1532 while (bufblks > log->l_logBBsize)
1533 bufblks >>= 1;
1534 while (!(buffer = xlog_alloc_buffer(log, bufblks))) {
1535 bufblks >>= 1;
1536 if (bufblks < sectbb)
1537 return -ENOMEM;
1538 }
1539
1540 /* We may need to do a read at the start to fill in part of
1541 * the buffer in the starting sector not covered by the first
1542 * write below.
1543 */
1544 balign = round_down(start_block, sectbb);
1545 if (balign != start_block) {
1546 error = xlog_bread_noalign(log, start_block, 1, buffer);
1547 if (error)
1548 goto out_free_buffer;
1549
1550 j = start_block - balign;
1551 }
1552
1553 for (i = start_block; i < end_block; i += bufblks) {
1554 int bcount, endcount;
1555
1556 bcount = min(bufblks, end_block - start_block);
1557 endcount = bcount - j;
1558
1559 /* We may need to do a read at the end to fill in part of
1560 * the buffer in the final sector not covered by the write.
1561 * If this is the same sector as the above read, skip it.
1562 */
1563 ealign = round_down(end_block, sectbb);
1564 if (j == 0 && (start_block + endcount > ealign)) {
1565 error = xlog_bread_noalign(log, ealign, sectbb,
1566 buffer + BBTOB(ealign - start_block));
1567 if (error)
1568 break;
1569
1570 }
1571
1572 offset = buffer + xlog_align(log, start_block);
1573 for (; j < endcount; j++) {
1574 xlog_add_record(log, offset, cycle, i+j,
1575 tail_cycle, tail_block);
1576 offset += BBSIZE;
1577 }
1578 error = xlog_bwrite(log, start_block, endcount, buffer);
1579 if (error)
1580 break;
1581 start_block += endcount;
1582 j = 0;
1583 }
1584
1585out_free_buffer:
1586 kvfree(buffer);
1587 return error;
1588}
1589
1590/*
1591 * This routine is called to blow away any incomplete log writes out
1592 * in front of the log head. We do this so that we won't become confused
1593 * if we come up, write only a little bit more, and then crash again.
1594 * If we leave the partial log records out there, this situation could
1595 * cause us to think those partial writes are valid blocks since they
1596 * have the current cycle number. We get rid of them by overwriting them
1597 * with empty log records with the old cycle number rather than the
1598 * current one.
1599 *
1600 * The tail lsn is passed in rather than taken from
1601 * the log so that we will not write over the unmount record after a
1602 * clean unmount in a 512 block log. Doing so would leave the log without
1603 * any valid log records in it until a new one was written. If we crashed
1604 * during that time we would not be able to recover.
1605 */
1606STATIC int
1607xlog_clear_stale_blocks(
1608 struct xlog *log,
1609 xfs_lsn_t tail_lsn)
1610{
1611 int tail_cycle, head_cycle;
1612 int tail_block, head_block;
1613 int tail_distance, max_distance;
1614 int distance;
1615 int error;
1616
1617 tail_cycle = CYCLE_LSN(tail_lsn);
1618 tail_block = BLOCK_LSN(tail_lsn);
1619 head_cycle = log->l_curr_cycle;
1620 head_block = log->l_curr_block;
1621
1622 /*
1623 * Figure out the distance between the new head of the log
1624 * and the tail. We want to write over any blocks beyond the
1625 * head that we may have written just before the crash, but
1626 * we don't want to overwrite the tail of the log.
1627 */
1628 if (head_cycle == tail_cycle) {
1629 /*
1630 * The tail is behind the head in the physical log,
1631 * so the distance from the head to the tail is the
1632 * distance from the head to the end of the log plus
1633 * the distance from the beginning of the log to the
1634 * tail.
1635 */
1636 if (XFS_IS_CORRUPT(log->l_mp,
1637 head_block < tail_block ||
1638 head_block >= log->l_logBBsize))
1639 return -EFSCORRUPTED;
1640 tail_distance = tail_block + (log->l_logBBsize - head_block);
1641 } else {
1642 /*
1643 * The head is behind the tail in the physical log,
1644 * so the distance from the head to the tail is just
1645 * the tail block minus the head block.
1646 */
1647 if (XFS_IS_CORRUPT(log->l_mp,
1648 head_block >= tail_block ||
1649 head_cycle != tail_cycle + 1))
1650 return -EFSCORRUPTED;
1651 tail_distance = tail_block - head_block;
1652 }
1653
1654 /*
1655 * If the head is right up against the tail, we can't clear
1656 * anything.
1657 */
1658 if (tail_distance <= 0) {
1659 ASSERT(tail_distance == 0);
1660 return 0;
1661 }
1662
1663 max_distance = XLOG_TOTAL_REC_SHIFT(log);
1664 /*
1665 * Take the smaller of the maximum amount of outstanding I/O
1666 * we could have and the distance to the tail to clear out.
1667 * We take the smaller so that we don't overwrite the tail and
1668 * we don't waste all day writing from the head to the tail
1669 * for no reason.
1670 */
1671 max_distance = min(max_distance, tail_distance);
1672
1673 if ((head_block + max_distance) <= log->l_logBBsize) {
1674 /*
1675 * We can stomp all the blocks we need to without
1676 * wrapping around the end of the log. Just do it
1677 * in a single write. Use the cycle number of the
1678 * current cycle minus one so that the log will look like:
1679 * n ... | n - 1 ...
1680 */
1681 error = xlog_write_log_records(log, (head_cycle - 1),
1682 head_block, max_distance, tail_cycle,
1683 tail_block);
1684 if (error)
1685 return error;
1686 } else {
1687 /*
1688 * We need to wrap around the end of the physical log in
1689 * order to clear all the blocks. Do it in two separate
1690 * I/Os. The first write should be from the head to the
1691 * end of the physical log, and it should use the current
1692 * cycle number minus one just like above.
1693 */
1694 distance = log->l_logBBsize - head_block;
1695 error = xlog_write_log_records(log, (head_cycle - 1),
1696 head_block, distance, tail_cycle,
1697 tail_block);
1698
1699 if (error)
1700 return error;
1701
1702 /*
1703 * Now write the blocks at the start of the physical log.
1704 * This writes the remainder of the blocks we want to clear.
1705 * It uses the current cycle number since we're now on the
1706 * same cycle as the head so that we get:
1707 * n ... n ... | n - 1 ...
1708 * ^^^^^ blocks we're writing
1709 */
1710 distance = max_distance - (log->l_logBBsize - head_block);
1711 error = xlog_write_log_records(log, head_cycle, 0, distance,
1712 tail_cycle, tail_block);
1713 if (error)
1714 return error;
1715 }
1716
1717 return 0;
1718}
1719
1720/*
1721 * Release the recovered intent item in the AIL that matches the given intent
1722 * type and intent id.
1723 */
1724void
1725xlog_recover_release_intent(
1726 struct xlog *log,
1727 unsigned short intent_type,
1728 uint64_t intent_id)
1729{
1730 struct xfs_defer_pending *dfp, *n;
1731
1732 list_for_each_entry_safe(dfp, n, &log->r_dfops, dfp_list) {
1733 struct xfs_log_item *lip = dfp->dfp_intent;
1734
1735 if (lip->li_type != intent_type)
1736 continue;
1737 if (!lip->li_ops->iop_match(lip, intent_id))
1738 continue;
1739
1740 ASSERT(xlog_item_is_intent(lip));
1741
1742 xfs_defer_cancel_recovery(log->l_mp, dfp);
1743 }
1744}
1745
1746int
1747xlog_recover_iget(
1748 struct xfs_mount *mp,
1749 xfs_ino_t ino,
1750 struct xfs_inode **ipp)
1751{
1752 int error;
1753
1754 error = xfs_iget(mp, NULL, ino, 0, 0, ipp);
1755 if (error)
1756 return error;
1757
1758 error = xfs_qm_dqattach(*ipp);
1759 if (error) {
1760 xfs_irele(*ipp);
1761 return error;
1762 }
1763
1764 if (VFS_I(*ipp)->i_nlink == 0)
1765 xfs_iflags_set(*ipp, XFS_IRECOVERY);
1766
1767 return 0;
1768}
1769
1770/******************************************************************************
1771 *
1772 * Log recover routines
1773 *
1774 ******************************************************************************
1775 */
1776static const struct xlog_recover_item_ops *xlog_recover_item_ops[] = {
1777 &xlog_buf_item_ops,
1778 &xlog_inode_item_ops,
1779 &xlog_dquot_item_ops,
1780 &xlog_quotaoff_item_ops,
1781 &xlog_icreate_item_ops,
1782 &xlog_efi_item_ops,
1783 &xlog_efd_item_ops,
1784 &xlog_rui_item_ops,
1785 &xlog_rud_item_ops,
1786 &xlog_cui_item_ops,
1787 &xlog_cud_item_ops,
1788 &xlog_bui_item_ops,
1789 &xlog_bud_item_ops,
1790 &xlog_attri_item_ops,
1791 &xlog_attrd_item_ops,
1792};
1793
1794static const struct xlog_recover_item_ops *
1795xlog_find_item_ops(
1796 struct xlog_recover_item *item)
1797{
1798 unsigned int i;
1799
1800 for (i = 0; i < ARRAY_SIZE(xlog_recover_item_ops); i++)
1801 if (ITEM_TYPE(item) == xlog_recover_item_ops[i]->item_type)
1802 return xlog_recover_item_ops[i];
1803
1804 return NULL;
1805}
1806
1807/*
1808 * Sort the log items in the transaction.
1809 *
1810 * The ordering constraints are defined by the inode allocation and unlink
1811 * behaviour. The rules are:
1812 *
1813 * 1. Every item is only logged once in a given transaction. Hence it
1814 * represents the last logged state of the item. Hence ordering is
1815 * dependent on the order in which operations need to be performed so
1816 * required initial conditions are always met.
1817 *
1818 * 2. Cancelled buffers are recorded in pass 1 in a separate table and
1819 * there's nothing to replay from them so we can simply cull them
1820 * from the transaction. However, we can't do that until after we've
1821 * replayed all the other items because they may be dependent on the
1822 * cancelled buffer and replaying the cancelled buffer can remove it
1823 * form the cancelled buffer table. Hence they have tobe done last.
1824 *
1825 * 3. Inode allocation buffers must be replayed before inode items that
1826 * read the buffer and replay changes into it. For filesystems using the
1827 * ICREATE transactions, this means XFS_LI_ICREATE objects need to get
1828 * treated the same as inode allocation buffers as they create and
1829 * initialise the buffers directly.
1830 *
1831 * 4. Inode unlink buffers must be replayed after inode items are replayed.
1832 * This ensures that inodes are completely flushed to the inode buffer
1833 * in a "free" state before we remove the unlinked inode list pointer.
1834 *
1835 * Hence the ordering needs to be inode allocation buffers first, inode items
1836 * second, inode unlink buffers third and cancelled buffers last.
1837 *
1838 * But there's a problem with that - we can't tell an inode allocation buffer
1839 * apart from a regular buffer, so we can't separate them. We can, however,
1840 * tell an inode unlink buffer from the others, and so we can separate them out
1841 * from all the other buffers and move them to last.
1842 *
1843 * Hence, 4 lists, in order from head to tail:
1844 * - buffer_list for all buffers except cancelled/inode unlink buffers
1845 * - item_list for all non-buffer items
1846 * - inode_buffer_list for inode unlink buffers
1847 * - cancel_list for the cancelled buffers
1848 *
1849 * Note that we add objects to the tail of the lists so that first-to-last
1850 * ordering is preserved within the lists. Adding objects to the head of the
1851 * list means when we traverse from the head we walk them in last-to-first
1852 * order. For cancelled buffers and inode unlink buffers this doesn't matter,
1853 * but for all other items there may be specific ordering that we need to
1854 * preserve.
1855 */
1856STATIC int
1857xlog_recover_reorder_trans(
1858 struct xlog *log,
1859 struct xlog_recover *trans,
1860 int pass)
1861{
1862 struct xlog_recover_item *item, *n;
1863 int error = 0;
1864 LIST_HEAD(sort_list);
1865 LIST_HEAD(cancel_list);
1866 LIST_HEAD(buffer_list);
1867 LIST_HEAD(inode_buffer_list);
1868 LIST_HEAD(item_list);
1869
1870 list_splice_init(&trans->r_itemq, &sort_list);
1871 list_for_each_entry_safe(item, n, &sort_list, ri_list) {
1872 enum xlog_recover_reorder fate = XLOG_REORDER_ITEM_LIST;
1873
1874 item->ri_ops = xlog_find_item_ops(item);
1875 if (!item->ri_ops) {
1876 xfs_warn(log->l_mp,
1877 "%s: unrecognized type of log operation (%d)",
1878 __func__, ITEM_TYPE(item));
1879 ASSERT(0);
1880 /*
1881 * return the remaining items back to the transaction
1882 * item list so they can be freed in caller.
1883 */
1884 if (!list_empty(&sort_list))
1885 list_splice_init(&sort_list, &trans->r_itemq);
1886 error = -EFSCORRUPTED;
1887 break;
1888 }
1889
1890 if (item->ri_ops->reorder)
1891 fate = item->ri_ops->reorder(item);
1892
1893 switch (fate) {
1894 case XLOG_REORDER_BUFFER_LIST:
1895 list_move_tail(&item->ri_list, &buffer_list);
1896 break;
1897 case XLOG_REORDER_CANCEL_LIST:
1898 trace_xfs_log_recover_item_reorder_head(log,
1899 trans, item, pass);
1900 list_move(&item->ri_list, &cancel_list);
1901 break;
1902 case XLOG_REORDER_INODE_BUFFER_LIST:
1903 list_move(&item->ri_list, &inode_buffer_list);
1904 break;
1905 case XLOG_REORDER_ITEM_LIST:
1906 trace_xfs_log_recover_item_reorder_tail(log,
1907 trans, item, pass);
1908 list_move_tail(&item->ri_list, &item_list);
1909 break;
1910 }
1911 }
1912
1913 ASSERT(list_empty(&sort_list));
1914 if (!list_empty(&buffer_list))
1915 list_splice(&buffer_list, &trans->r_itemq);
1916 if (!list_empty(&item_list))
1917 list_splice_tail(&item_list, &trans->r_itemq);
1918 if (!list_empty(&inode_buffer_list))
1919 list_splice_tail(&inode_buffer_list, &trans->r_itemq);
1920 if (!list_empty(&cancel_list))
1921 list_splice_tail(&cancel_list, &trans->r_itemq);
1922 return error;
1923}
1924
1925void
1926xlog_buf_readahead(
1927 struct xlog *log,
1928 xfs_daddr_t blkno,
1929 uint len,
1930 const struct xfs_buf_ops *ops)
1931{
1932 if (!xlog_is_buffer_cancelled(log, blkno, len))
1933 xfs_buf_readahead(log->l_mp->m_ddev_targp, blkno, len, ops);
1934}
1935
1936/*
1937 * Create a deferred work structure for resuming and tracking the progress of a
1938 * log intent item that was found during recovery.
1939 */
1940void
1941xlog_recover_intent_item(
1942 struct xlog *log,
1943 struct xfs_log_item *lip,
1944 xfs_lsn_t lsn,
1945 const struct xfs_defer_op_type *ops)
1946{
1947 ASSERT(xlog_item_is_intent(lip));
1948
1949 xfs_defer_start_recovery(lip, &log->r_dfops, ops);
1950
1951 /*
1952 * Insert the intent into the AIL directly and drop one reference so
1953 * that finishing or canceling the work will drop the other.
1954 */
1955 xfs_trans_ail_insert(log->l_ailp, lip, lsn);
1956 lip->li_ops->iop_unpin(lip, 0);
1957}
1958
1959STATIC int
1960xlog_recover_items_pass2(
1961 struct xlog *log,
1962 struct xlog_recover *trans,
1963 struct list_head *buffer_list,
1964 struct list_head *item_list)
1965{
1966 struct xlog_recover_item *item;
1967 int error = 0;
1968
1969 list_for_each_entry(item, item_list, ri_list) {
1970 trace_xfs_log_recover_item_recover(log, trans, item,
1971 XLOG_RECOVER_PASS2);
1972
1973 if (item->ri_ops->commit_pass2)
1974 error = item->ri_ops->commit_pass2(log, buffer_list,
1975 item, trans->r_lsn);
1976 if (error)
1977 return error;
1978 }
1979
1980 return error;
1981}
1982
1983/*
1984 * Perform the transaction.
1985 *
1986 * If the transaction modifies a buffer or inode, do it now. Otherwise,
1987 * EFIs and EFDs get queued up by adding entries into the AIL for them.
1988 */
1989STATIC int
1990xlog_recover_commit_trans(
1991 struct xlog *log,
1992 struct xlog_recover *trans,
1993 int pass,
1994 struct list_head *buffer_list)
1995{
1996 int error = 0;
1997 int items_queued = 0;
1998 struct xlog_recover_item *item;
1999 struct xlog_recover_item *next;
2000 LIST_HEAD (ra_list);
2001 LIST_HEAD (done_list);
2002
2003 #define XLOG_RECOVER_COMMIT_QUEUE_MAX 100
2004
2005 hlist_del_init(&trans->r_list);
2006
2007 error = xlog_recover_reorder_trans(log, trans, pass);
2008 if (error)
2009 return error;
2010
2011 list_for_each_entry_safe(item, next, &trans->r_itemq, ri_list) {
2012 trace_xfs_log_recover_item_recover(log, trans, item, pass);
2013
2014 switch (pass) {
2015 case XLOG_RECOVER_PASS1:
2016 if (item->ri_ops->commit_pass1)
2017 error = item->ri_ops->commit_pass1(log, item);
2018 break;
2019 case XLOG_RECOVER_PASS2:
2020 if (item->ri_ops->ra_pass2)
2021 item->ri_ops->ra_pass2(log, item);
2022 list_move_tail(&item->ri_list, &ra_list);
2023 items_queued++;
2024 if (items_queued >= XLOG_RECOVER_COMMIT_QUEUE_MAX) {
2025 error = xlog_recover_items_pass2(log, trans,
2026 buffer_list, &ra_list);
2027 list_splice_tail_init(&ra_list, &done_list);
2028 items_queued = 0;
2029 }
2030
2031 break;
2032 default:
2033 ASSERT(0);
2034 }
2035
2036 if (error)
2037 goto out;
2038 }
2039
2040out:
2041 if (!list_empty(&ra_list)) {
2042 if (!error)
2043 error = xlog_recover_items_pass2(log, trans,
2044 buffer_list, &ra_list);
2045 list_splice_tail_init(&ra_list, &done_list);
2046 }
2047
2048 if (!list_empty(&done_list))
2049 list_splice_init(&done_list, &trans->r_itemq);
2050
2051 return error;
2052}
2053
2054STATIC void
2055xlog_recover_add_item(
2056 struct list_head *head)
2057{
2058 struct xlog_recover_item *item;
2059
2060 item = kzalloc(sizeof(struct xlog_recover_item),
2061 GFP_KERNEL | __GFP_NOFAIL);
2062 INIT_LIST_HEAD(&item->ri_list);
2063 list_add_tail(&item->ri_list, head);
2064}
2065
2066STATIC int
2067xlog_recover_add_to_cont_trans(
2068 struct xlog *log,
2069 struct xlog_recover *trans,
2070 char *dp,
2071 int len)
2072{
2073 struct xlog_recover_item *item;
2074 char *ptr, *old_ptr;
2075 int old_len;
2076
2077 /*
2078 * If the transaction is empty, the header was split across this and the
2079 * previous record. Copy the rest of the header.
2080 */
2081 if (list_empty(&trans->r_itemq)) {
2082 ASSERT(len <= sizeof(struct xfs_trans_header));
2083 if (len > sizeof(struct xfs_trans_header)) {
2084 xfs_warn(log->l_mp, "%s: bad header length", __func__);
2085 return -EFSCORRUPTED;
2086 }
2087
2088 xlog_recover_add_item(&trans->r_itemq);
2089 ptr = (char *)&trans->r_theader +
2090 sizeof(struct xfs_trans_header) - len;
2091 memcpy(ptr, dp, len);
2092 return 0;
2093 }
2094
2095 /* take the tail entry */
2096 item = list_entry(trans->r_itemq.prev, struct xlog_recover_item,
2097 ri_list);
2098
2099 old_ptr = item->ri_buf[item->ri_cnt-1].i_addr;
2100 old_len = item->ri_buf[item->ri_cnt-1].i_len;
2101
2102 ptr = kvrealloc(old_ptr, old_len, len + old_len, GFP_KERNEL);
2103 if (!ptr)
2104 return -ENOMEM;
2105 memcpy(&ptr[old_len], dp, len);
2106 item->ri_buf[item->ri_cnt-1].i_len += len;
2107 item->ri_buf[item->ri_cnt-1].i_addr = ptr;
2108 trace_xfs_log_recover_item_add_cont(log, trans, item, 0);
2109 return 0;
2110}
2111
2112/*
2113 * The next region to add is the start of a new region. It could be
2114 * a whole region or it could be the first part of a new region. Because
2115 * of this, the assumption here is that the type and size fields of all
2116 * format structures fit into the first 32 bits of the structure.
2117 *
2118 * This works because all regions must be 32 bit aligned. Therefore, we
2119 * either have both fields or we have neither field. In the case we have
2120 * neither field, the data part of the region is zero length. We only have
2121 * a log_op_header and can throw away the header since a new one will appear
2122 * later. If we have at least 4 bytes, then we can determine how many regions
2123 * will appear in the current log item.
2124 */
2125STATIC int
2126xlog_recover_add_to_trans(
2127 struct xlog *log,
2128 struct xlog_recover *trans,
2129 char *dp,
2130 int len)
2131{
2132 struct xfs_inode_log_format *in_f; /* any will do */
2133 struct xlog_recover_item *item;
2134 char *ptr;
2135
2136 if (!len)
2137 return 0;
2138 if (list_empty(&trans->r_itemq)) {
2139 /* we need to catch log corruptions here */
2140 if (*(uint *)dp != XFS_TRANS_HEADER_MAGIC) {
2141 xfs_warn(log->l_mp, "%s: bad header magic number",
2142 __func__);
2143 ASSERT(0);
2144 return -EFSCORRUPTED;
2145 }
2146
2147 if (len > sizeof(struct xfs_trans_header)) {
2148 xfs_warn(log->l_mp, "%s: bad header length", __func__);
2149 ASSERT(0);
2150 return -EFSCORRUPTED;
2151 }
2152
2153 /*
2154 * The transaction header can be arbitrarily split across op
2155 * records. If we don't have the whole thing here, copy what we
2156 * do have and handle the rest in the next record.
2157 */
2158 if (len == sizeof(struct xfs_trans_header))
2159 xlog_recover_add_item(&trans->r_itemq);
2160 memcpy(&trans->r_theader, dp, len);
2161 return 0;
2162 }
2163
2164 ptr = xlog_kvmalloc(len);
2165 memcpy(ptr, dp, len);
2166 in_f = (struct xfs_inode_log_format *)ptr;
2167
2168 /* take the tail entry */
2169 item = list_entry(trans->r_itemq.prev, struct xlog_recover_item,
2170 ri_list);
2171 if (item->ri_total != 0 &&
2172 item->ri_total == item->ri_cnt) {
2173 /* tail item is in use, get a new one */
2174 xlog_recover_add_item(&trans->r_itemq);
2175 item = list_entry(trans->r_itemq.prev,
2176 struct xlog_recover_item, ri_list);
2177 }
2178
2179 if (item->ri_total == 0) { /* first region to be added */
2180 if (in_f->ilf_size == 0 ||
2181 in_f->ilf_size > XLOG_MAX_REGIONS_IN_ITEM) {
2182 xfs_warn(log->l_mp,
2183 "bad number of regions (%d) in inode log format",
2184 in_f->ilf_size);
2185 ASSERT(0);
2186 kvfree(ptr);
2187 return -EFSCORRUPTED;
2188 }
2189
2190 item->ri_total = in_f->ilf_size;
2191 item->ri_buf = kzalloc(item->ri_total * sizeof(xfs_log_iovec_t),
2192 GFP_KERNEL | __GFP_NOFAIL);
2193 }
2194
2195 if (item->ri_total <= item->ri_cnt) {
2196 xfs_warn(log->l_mp,
2197 "log item region count (%d) overflowed size (%d)",
2198 item->ri_cnt, item->ri_total);
2199 ASSERT(0);
2200 kvfree(ptr);
2201 return -EFSCORRUPTED;
2202 }
2203
2204 /* Description region is ri_buf[0] */
2205 item->ri_buf[item->ri_cnt].i_addr = ptr;
2206 item->ri_buf[item->ri_cnt].i_len = len;
2207 item->ri_cnt++;
2208 trace_xfs_log_recover_item_add(log, trans, item, 0);
2209 return 0;
2210}
2211
2212/*
2213 * Free up any resources allocated by the transaction
2214 *
2215 * Remember that EFIs, EFDs, and IUNLINKs are handled later.
2216 */
2217STATIC void
2218xlog_recover_free_trans(
2219 struct xlog_recover *trans)
2220{
2221 struct xlog_recover_item *item, *n;
2222 int i;
2223
2224 hlist_del_init(&trans->r_list);
2225
2226 list_for_each_entry_safe(item, n, &trans->r_itemq, ri_list) {
2227 /* Free the regions in the item. */
2228 list_del(&item->ri_list);
2229 for (i = 0; i < item->ri_cnt; i++)
2230 kvfree(item->ri_buf[i].i_addr);
2231 /* Free the item itself */
2232 kfree(item->ri_buf);
2233 kfree(item);
2234 }
2235 /* Free the transaction recover structure */
2236 kfree(trans);
2237}
2238
2239/*
2240 * On error or completion, trans is freed.
2241 */
2242STATIC int
2243xlog_recovery_process_trans(
2244 struct xlog *log,
2245 struct xlog_recover *trans,
2246 char *dp,
2247 unsigned int len,
2248 unsigned int flags,
2249 int pass,
2250 struct list_head *buffer_list)
2251{
2252 int error = 0;
2253 bool freeit = false;
2254
2255 /* mask off ophdr transaction container flags */
2256 flags &= ~XLOG_END_TRANS;
2257 if (flags & XLOG_WAS_CONT_TRANS)
2258 flags &= ~XLOG_CONTINUE_TRANS;
2259
2260 /*
2261 * Callees must not free the trans structure. We'll decide if we need to
2262 * free it or not based on the operation being done and it's result.
2263 */
2264 switch (flags) {
2265 /* expected flag values */
2266 case 0:
2267 case XLOG_CONTINUE_TRANS:
2268 error = xlog_recover_add_to_trans(log, trans, dp, len);
2269 break;
2270 case XLOG_WAS_CONT_TRANS:
2271 error = xlog_recover_add_to_cont_trans(log, trans, dp, len);
2272 break;
2273 case XLOG_COMMIT_TRANS:
2274 error = xlog_recover_commit_trans(log, trans, pass,
2275 buffer_list);
2276 /* success or fail, we are now done with this transaction. */
2277 freeit = true;
2278 break;
2279
2280 /* unexpected flag values */
2281 case XLOG_UNMOUNT_TRANS:
2282 /* just skip trans */
2283 xfs_warn(log->l_mp, "%s: Unmount LR", __func__);
2284 freeit = true;
2285 break;
2286 case XLOG_START_TRANS:
2287 default:
2288 xfs_warn(log->l_mp, "%s: bad flag 0x%x", __func__, flags);
2289 ASSERT(0);
2290 error = -EFSCORRUPTED;
2291 break;
2292 }
2293 if (error || freeit)
2294 xlog_recover_free_trans(trans);
2295 return error;
2296}
2297
2298/*
2299 * Lookup the transaction recovery structure associated with the ID in the
2300 * current ophdr. If the transaction doesn't exist and the start flag is set in
2301 * the ophdr, then allocate a new transaction for future ID matches to find.
2302 * Either way, return what we found during the lookup - an existing transaction
2303 * or nothing.
2304 */
2305STATIC struct xlog_recover *
2306xlog_recover_ophdr_to_trans(
2307 struct hlist_head rhash[],
2308 struct xlog_rec_header *rhead,
2309 struct xlog_op_header *ohead)
2310{
2311 struct xlog_recover *trans;
2312 xlog_tid_t tid;
2313 struct hlist_head *rhp;
2314
2315 tid = be32_to_cpu(ohead->oh_tid);
2316 rhp = &rhash[XLOG_RHASH(tid)];
2317 hlist_for_each_entry(trans, rhp, r_list) {
2318 if (trans->r_log_tid == tid)
2319 return trans;
2320 }
2321
2322 /*
2323 * skip over non-start transaction headers - we could be
2324 * processing slack space before the next transaction starts
2325 */
2326 if (!(ohead->oh_flags & XLOG_START_TRANS))
2327 return NULL;
2328
2329 ASSERT(be32_to_cpu(ohead->oh_len) == 0);
2330
2331 /*
2332 * This is a new transaction so allocate a new recovery container to
2333 * hold the recovery ops that will follow.
2334 */
2335 trans = kzalloc(sizeof(struct xlog_recover), GFP_KERNEL | __GFP_NOFAIL);
2336 trans->r_log_tid = tid;
2337 trans->r_lsn = be64_to_cpu(rhead->h_lsn);
2338 INIT_LIST_HEAD(&trans->r_itemq);
2339 INIT_HLIST_NODE(&trans->r_list);
2340 hlist_add_head(&trans->r_list, rhp);
2341
2342 /*
2343 * Nothing more to do for this ophdr. Items to be added to this new
2344 * transaction will be in subsequent ophdr containers.
2345 */
2346 return NULL;
2347}
2348
2349STATIC int
2350xlog_recover_process_ophdr(
2351 struct xlog *log,
2352 struct hlist_head rhash[],
2353 struct xlog_rec_header *rhead,
2354 struct xlog_op_header *ohead,
2355 char *dp,
2356 char *end,
2357 int pass,
2358 struct list_head *buffer_list)
2359{
2360 struct xlog_recover *trans;
2361 unsigned int len;
2362 int error;
2363
2364 /* Do we understand who wrote this op? */
2365 if (ohead->oh_clientid != XFS_TRANSACTION &&
2366 ohead->oh_clientid != XFS_LOG) {
2367 xfs_warn(log->l_mp, "%s: bad clientid 0x%x",
2368 __func__, ohead->oh_clientid);
2369 ASSERT(0);
2370 return -EFSCORRUPTED;
2371 }
2372
2373 /*
2374 * Check the ophdr contains all the data it is supposed to contain.
2375 */
2376 len = be32_to_cpu(ohead->oh_len);
2377 if (dp + len > end) {
2378 xfs_warn(log->l_mp, "%s: bad length 0x%x", __func__, len);
2379 WARN_ON(1);
2380 return -EFSCORRUPTED;
2381 }
2382
2383 trans = xlog_recover_ophdr_to_trans(rhash, rhead, ohead);
2384 if (!trans) {
2385 /* nothing to do, so skip over this ophdr */
2386 return 0;
2387 }
2388
2389 /*
2390 * The recovered buffer queue is drained only once we know that all
2391 * recovery items for the current LSN have been processed. This is
2392 * required because:
2393 *
2394 * - Buffer write submission updates the metadata LSN of the buffer.
2395 * - Log recovery skips items with a metadata LSN >= the current LSN of
2396 * the recovery item.
2397 * - Separate recovery items against the same metadata buffer can share
2398 * a current LSN. I.e., consider that the LSN of a recovery item is
2399 * defined as the starting LSN of the first record in which its
2400 * transaction appears, that a record can hold multiple transactions,
2401 * and/or that a transaction can span multiple records.
2402 *
2403 * In other words, we are allowed to submit a buffer from log recovery
2404 * once per current LSN. Otherwise, we may incorrectly skip recovery
2405 * items and cause corruption.
2406 *
2407 * We don't know up front whether buffers are updated multiple times per
2408 * LSN. Therefore, track the current LSN of each commit log record as it
2409 * is processed and drain the queue when it changes. Use commit records
2410 * because they are ordered correctly by the logging code.
2411 */
2412 if (log->l_recovery_lsn != trans->r_lsn &&
2413 ohead->oh_flags & XLOG_COMMIT_TRANS) {
2414 error = xfs_buf_delwri_submit(buffer_list);
2415 if (error)
2416 return error;
2417 log->l_recovery_lsn = trans->r_lsn;
2418 }
2419
2420 return xlog_recovery_process_trans(log, trans, dp, len,
2421 ohead->oh_flags, pass, buffer_list);
2422}
2423
2424/*
2425 * There are two valid states of the r_state field. 0 indicates that the
2426 * transaction structure is in a normal state. We have either seen the
2427 * start of the transaction or the last operation we added was not a partial
2428 * operation. If the last operation we added to the transaction was a
2429 * partial operation, we need to mark r_state with XLOG_WAS_CONT_TRANS.
2430 *
2431 * NOTE: skip LRs with 0 data length.
2432 */
2433STATIC int
2434xlog_recover_process_data(
2435 struct xlog *log,
2436 struct hlist_head rhash[],
2437 struct xlog_rec_header *rhead,
2438 char *dp,
2439 int pass,
2440 struct list_head *buffer_list)
2441{
2442 struct xlog_op_header *ohead;
2443 char *end;
2444 int num_logops;
2445 int error;
2446
2447 end = dp + be32_to_cpu(rhead->h_len);
2448 num_logops = be32_to_cpu(rhead->h_num_logops);
2449
2450 /* check the log format matches our own - else we can't recover */
2451 if (xlog_header_check_recover(log->l_mp, rhead))
2452 return -EIO;
2453
2454 trace_xfs_log_recover_record(log, rhead, pass);
2455 while ((dp < end) && num_logops) {
2456
2457 ohead = (struct xlog_op_header *)dp;
2458 dp += sizeof(*ohead);
2459 ASSERT(dp <= end);
2460
2461 /* errors will abort recovery */
2462 error = xlog_recover_process_ophdr(log, rhash, rhead, ohead,
2463 dp, end, pass, buffer_list);
2464 if (error)
2465 return error;
2466
2467 dp += be32_to_cpu(ohead->oh_len);
2468 num_logops--;
2469 }
2470 return 0;
2471}
2472
2473/* Take all the collected deferred ops and finish them in order. */
2474static int
2475xlog_finish_defer_ops(
2476 struct xfs_mount *mp,
2477 struct list_head *capture_list)
2478{
2479 struct xfs_defer_capture *dfc, *next;
2480 struct xfs_trans *tp;
2481 int error = 0;
2482
2483 list_for_each_entry_safe(dfc, next, capture_list, dfc_list) {
2484 struct xfs_trans_res resv;
2485 struct xfs_defer_resources dres;
2486
2487 /*
2488 * Create a new transaction reservation from the captured
2489 * information. Set logcount to 1 to force the new transaction
2490 * to regrant every roll so that we can make forward progress
2491 * in recovery no matter how full the log might be.
2492 */
2493 resv.tr_logres = dfc->dfc_logres;
2494 resv.tr_logcount = 1;
2495 resv.tr_logflags = XFS_TRANS_PERM_LOG_RES;
2496
2497 error = xfs_trans_alloc(mp, &resv, dfc->dfc_blkres,
2498 dfc->dfc_rtxres, XFS_TRANS_RESERVE, &tp);
2499 if (error) {
2500 xlog_force_shutdown(mp->m_log, SHUTDOWN_LOG_IO_ERROR);
2501 return error;
2502 }
2503
2504 /*
2505 * Transfer to this new transaction all the dfops we captured
2506 * from recovering a single intent item.
2507 */
2508 list_del_init(&dfc->dfc_list);
2509 xfs_defer_ops_continue(dfc, tp, &dres);
2510 error = xfs_trans_commit(tp);
2511 xfs_defer_resources_rele(&dres);
2512 if (error)
2513 return error;
2514 }
2515
2516 ASSERT(list_empty(capture_list));
2517 return 0;
2518}
2519
2520/* Release all the captured defer ops and capture structures in this list. */
2521static void
2522xlog_abort_defer_ops(
2523 struct xfs_mount *mp,
2524 struct list_head *capture_list)
2525{
2526 struct xfs_defer_capture *dfc;
2527 struct xfs_defer_capture *next;
2528
2529 list_for_each_entry_safe(dfc, next, capture_list, dfc_list) {
2530 list_del_init(&dfc->dfc_list);
2531 xfs_defer_ops_capture_abort(mp, dfc);
2532 }
2533}
2534
2535/*
2536 * When this is called, all of the log intent items which did not have
2537 * corresponding log done items should be in the AIL. What we do now is update
2538 * the data structures associated with each one.
2539 *
2540 * Since we process the log intent items in normal transactions, they will be
2541 * removed at some point after the commit. This prevents us from just walking
2542 * down the list processing each one. We'll use a flag in the intent item to
2543 * skip those that we've already processed and use the AIL iteration mechanism's
2544 * generation count to try to speed this up at least a bit.
2545 *
2546 * When we start, we know that the intents are the only things in the AIL. As we
2547 * process them, however, other items are added to the AIL. Hence we know we
2548 * have started recovery on all the pending intents when we find an non-intent
2549 * item in the AIL.
2550 */
2551STATIC int
2552xlog_recover_process_intents(
2553 struct xlog *log)
2554{
2555 LIST_HEAD(capture_list);
2556 struct xfs_defer_pending *dfp, *n;
2557 int error = 0;
2558#if defined(DEBUG) || defined(XFS_WARN)
2559 xfs_lsn_t last_lsn;
2560
2561 last_lsn = xlog_assign_lsn(log->l_curr_cycle, log->l_curr_block);
2562#endif
2563
2564 list_for_each_entry_safe(dfp, n, &log->r_dfops, dfp_list) {
2565 ASSERT(xlog_item_is_intent(dfp->dfp_intent));
2566
2567 /*
2568 * We should never see a redo item with a LSN higher than
2569 * the last transaction we found in the log at the start
2570 * of recovery.
2571 */
2572 ASSERT(XFS_LSN_CMP(last_lsn, dfp->dfp_intent->li_lsn) >= 0);
2573
2574 /*
2575 * NOTE: If your intent processing routine can create more
2576 * deferred ops, you /must/ attach them to the capture list in
2577 * the recover routine or else those subsequent intents will be
2578 * replayed in the wrong order!
2579 *
2580 * The recovery function can free the log item, so we must not
2581 * access dfp->dfp_intent after it returns. It must dispose of
2582 * @dfp if it returns 0.
2583 */
2584 error = xfs_defer_finish_recovery(log->l_mp, dfp,
2585 &capture_list);
2586 if (error)
2587 break;
2588 }
2589 if (error)
2590 goto err;
2591
2592 error = xlog_finish_defer_ops(log->l_mp, &capture_list);
2593 if (error)
2594 goto err;
2595
2596 return 0;
2597err:
2598 xlog_abort_defer_ops(log->l_mp, &capture_list);
2599 return error;
2600}
2601
2602/*
2603 * A cancel occurs when the mount has failed and we're bailing out. Release all
2604 * pending log intent items that we haven't started recovery on so they don't
2605 * pin the AIL.
2606 */
2607STATIC void
2608xlog_recover_cancel_intents(
2609 struct xlog *log)
2610{
2611 struct xfs_defer_pending *dfp, *n;
2612
2613 list_for_each_entry_safe(dfp, n, &log->r_dfops, dfp_list) {
2614 ASSERT(xlog_item_is_intent(dfp->dfp_intent));
2615
2616 xfs_defer_cancel_recovery(log->l_mp, dfp);
2617 }
2618}
2619
2620/*
2621 * Transfer ownership of the recovered pending work to the recovery transaction
2622 * and try to finish the work. If there is more work to be done, the dfp will
2623 * remain attached to the transaction. If not, the dfp is freed.
2624 */
2625int
2626xlog_recover_finish_intent(
2627 struct xfs_trans *tp,
2628 struct xfs_defer_pending *dfp)
2629{
2630 int error;
2631
2632 list_move(&dfp->dfp_list, &tp->t_dfops);
2633 error = xfs_defer_finish_one(tp, dfp);
2634 if (error == -EAGAIN)
2635 return 0;
2636 return error;
2637}
2638
2639/*
2640 * This routine performs a transaction to null out a bad inode pointer
2641 * in an agi unlinked inode hash bucket.
2642 */
2643STATIC void
2644xlog_recover_clear_agi_bucket(
2645 struct xfs_perag *pag,
2646 int bucket)
2647{
2648 struct xfs_mount *mp = pag->pag_mount;
2649 struct xfs_trans *tp;
2650 struct xfs_agi *agi;
2651 struct xfs_buf *agibp;
2652 int offset;
2653 int error;
2654
2655 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_clearagi, 0, 0, 0, &tp);
2656 if (error)
2657 goto out_error;
2658
2659 error = xfs_read_agi(pag, tp, &agibp);
2660 if (error)
2661 goto out_abort;
2662
2663 agi = agibp->b_addr;
2664 agi->agi_unlinked[bucket] = cpu_to_be32(NULLAGINO);
2665 offset = offsetof(xfs_agi_t, agi_unlinked) +
2666 (sizeof(xfs_agino_t) * bucket);
2667 xfs_trans_log_buf(tp, agibp, offset,
2668 (offset + sizeof(xfs_agino_t) - 1));
2669
2670 error = xfs_trans_commit(tp);
2671 if (error)
2672 goto out_error;
2673 return;
2674
2675out_abort:
2676 xfs_trans_cancel(tp);
2677out_error:
2678 xfs_warn(mp, "%s: failed to clear agi %d. Continuing.", __func__,
2679 pag->pag_agno);
2680 return;
2681}
2682
2683static int
2684xlog_recover_iunlink_bucket(
2685 struct xfs_perag *pag,
2686 struct xfs_agi *agi,
2687 int bucket)
2688{
2689 struct xfs_mount *mp = pag->pag_mount;
2690 struct xfs_inode *prev_ip = NULL;
2691 struct xfs_inode *ip;
2692 xfs_agino_t prev_agino, agino;
2693 int error = 0;
2694
2695 agino = be32_to_cpu(agi->agi_unlinked[bucket]);
2696 while (agino != NULLAGINO) {
2697 error = xfs_iget(mp, NULL,
2698 XFS_AGINO_TO_INO(mp, pag->pag_agno, agino),
2699 0, 0, &ip);
2700 if (error)
2701 break;
2702
2703 ASSERT(VFS_I(ip)->i_nlink == 0);
2704 ASSERT(VFS_I(ip)->i_mode != 0);
2705 xfs_iflags_clear(ip, XFS_IRECOVERY);
2706 agino = ip->i_next_unlinked;
2707
2708 if (prev_ip) {
2709 ip->i_prev_unlinked = prev_agino;
2710 xfs_irele(prev_ip);
2711
2712 /*
2713 * Ensure the inode is removed from the unlinked list
2714 * before we continue so that it won't race with
2715 * building the in-memory list here. This could be
2716 * serialised with the agibp lock, but that just
2717 * serialises via lockstepping and it's much simpler
2718 * just to flush the inodegc queue and wait for it to
2719 * complete.
2720 */
2721 error = xfs_inodegc_flush(mp);
2722 if (error)
2723 break;
2724 }
2725
2726 prev_agino = agino;
2727 prev_ip = ip;
2728 }
2729
2730 if (prev_ip) {
2731 int error2;
2732
2733 ip->i_prev_unlinked = prev_agino;
2734 xfs_irele(prev_ip);
2735
2736 error2 = xfs_inodegc_flush(mp);
2737 if (error2 && !error)
2738 return error2;
2739 }
2740 return error;
2741}
2742
2743/*
2744 * Recover AGI unlinked lists
2745 *
2746 * This is called during recovery to process any inodes which we unlinked but
2747 * not freed when the system crashed. These inodes will be on the lists in the
2748 * AGI blocks. What we do here is scan all the AGIs and fully truncate and free
2749 * any inodes found on the lists. Each inode is removed from the lists when it
2750 * has been fully truncated and is freed. The freeing of the inode and its
2751 * removal from the list must be atomic.
2752 *
2753 * If everything we touch in the agi processing loop is already in memory, this
2754 * loop can hold the cpu for a long time. It runs without lock contention,
2755 * memory allocation contention, the need wait for IO, etc, and so will run
2756 * until we either run out of inodes to process, run low on memory or we run out
2757 * of log space.
2758 *
2759 * This behaviour is bad for latency on single CPU and non-preemptible kernels,
2760 * and can prevent other filesystem work (such as CIL pushes) from running. This
2761 * can lead to deadlocks if the recovery process runs out of log reservation
2762 * space. Hence we need to yield the CPU when there is other kernel work
2763 * scheduled on this CPU to ensure other scheduled work can run without undue
2764 * latency.
2765 */
2766static void
2767xlog_recover_iunlink_ag(
2768 struct xfs_perag *pag)
2769{
2770 struct xfs_agi *agi;
2771 struct xfs_buf *agibp;
2772 int bucket;
2773 int error;
2774
2775 error = xfs_read_agi(pag, NULL, &agibp);
2776 if (error) {
2777 /*
2778 * AGI is b0rked. Don't process it.
2779 *
2780 * We should probably mark the filesystem as corrupt after we've
2781 * recovered all the ag's we can....
2782 */
2783 return;
2784 }
2785
2786 /*
2787 * Unlock the buffer so that it can be acquired in the normal course of
2788 * the transaction to truncate and free each inode. Because we are not
2789 * racing with anyone else here for the AGI buffer, we don't even need
2790 * to hold it locked to read the initial unlinked bucket entries out of
2791 * the buffer. We keep buffer reference though, so that it stays pinned
2792 * in memory while we need the buffer.
2793 */
2794 agi = agibp->b_addr;
2795 xfs_buf_unlock(agibp);
2796
2797 for (bucket = 0; bucket < XFS_AGI_UNLINKED_BUCKETS; bucket++) {
2798 error = xlog_recover_iunlink_bucket(pag, agi, bucket);
2799 if (error) {
2800 /*
2801 * Bucket is unrecoverable, so only a repair scan can
2802 * free the remaining unlinked inodes. Just empty the
2803 * bucket and remaining inodes on it unreferenced and
2804 * unfreeable.
2805 */
2806 xlog_recover_clear_agi_bucket(pag, bucket);
2807 }
2808 }
2809
2810 xfs_buf_rele(agibp);
2811}
2812
2813static void
2814xlog_recover_process_iunlinks(
2815 struct xlog *log)
2816{
2817 struct xfs_perag *pag;
2818 xfs_agnumber_t agno;
2819
2820 for_each_perag(log->l_mp, agno, pag)
2821 xlog_recover_iunlink_ag(pag);
2822}
2823
2824STATIC void
2825xlog_unpack_data(
2826 struct xlog_rec_header *rhead,
2827 char *dp,
2828 struct xlog *log)
2829{
2830 int i, j, k;
2831
2832 for (i = 0; i < BTOBB(be32_to_cpu(rhead->h_len)) &&
2833 i < (XLOG_HEADER_CYCLE_SIZE / BBSIZE); i++) {
2834 *(__be32 *)dp = *(__be32 *)&rhead->h_cycle_data[i];
2835 dp += BBSIZE;
2836 }
2837
2838 if (xfs_has_logv2(log->l_mp)) {
2839 xlog_in_core_2_t *xhdr = (xlog_in_core_2_t *)rhead;
2840 for ( ; i < BTOBB(be32_to_cpu(rhead->h_len)); i++) {
2841 j = i / (XLOG_HEADER_CYCLE_SIZE / BBSIZE);
2842 k = i % (XLOG_HEADER_CYCLE_SIZE / BBSIZE);
2843 *(__be32 *)dp = xhdr[j].hic_xheader.xh_cycle_data[k];
2844 dp += BBSIZE;
2845 }
2846 }
2847}
2848
2849/*
2850 * CRC check, unpack and process a log record.
2851 */
2852STATIC int
2853xlog_recover_process(
2854 struct xlog *log,
2855 struct hlist_head rhash[],
2856 struct xlog_rec_header *rhead,
2857 char *dp,
2858 int pass,
2859 struct list_head *buffer_list)
2860{
2861 __le32 old_crc = rhead->h_crc;
2862 __le32 crc;
2863
2864 crc = xlog_cksum(log, rhead, dp, be32_to_cpu(rhead->h_len));
2865
2866 /*
2867 * Nothing else to do if this is a CRC verification pass. Just return
2868 * if this a record with a non-zero crc. Unfortunately, mkfs always
2869 * sets old_crc to 0 so we must consider this valid even on v5 supers.
2870 * Otherwise, return EFSBADCRC on failure so the callers up the stack
2871 * know precisely what failed.
2872 */
2873 if (pass == XLOG_RECOVER_CRCPASS) {
2874 if (old_crc && crc != old_crc)
2875 return -EFSBADCRC;
2876 return 0;
2877 }
2878
2879 /*
2880 * We're in the normal recovery path. Issue a warning if and only if the
2881 * CRC in the header is non-zero. This is an advisory warning and the
2882 * zero CRC check prevents warnings from being emitted when upgrading
2883 * the kernel from one that does not add CRCs by default.
2884 */
2885 if (crc != old_crc) {
2886 if (old_crc || xfs_has_crc(log->l_mp)) {
2887 xfs_alert(log->l_mp,
2888 "log record CRC mismatch: found 0x%x, expected 0x%x.",
2889 le32_to_cpu(old_crc),
2890 le32_to_cpu(crc));
2891 xfs_hex_dump(dp, 32);
2892 }
2893
2894 /*
2895 * If the filesystem is CRC enabled, this mismatch becomes a
2896 * fatal log corruption failure.
2897 */
2898 if (xfs_has_crc(log->l_mp)) {
2899 XFS_ERROR_REPORT(__func__, XFS_ERRLEVEL_LOW, log->l_mp);
2900 return -EFSCORRUPTED;
2901 }
2902 }
2903
2904 xlog_unpack_data(rhead, dp, log);
2905
2906 return xlog_recover_process_data(log, rhash, rhead, dp, pass,
2907 buffer_list);
2908}
2909
2910STATIC int
2911xlog_valid_rec_header(
2912 struct xlog *log,
2913 struct xlog_rec_header *rhead,
2914 xfs_daddr_t blkno,
2915 int bufsize)
2916{
2917 int hlen;
2918
2919 if (XFS_IS_CORRUPT(log->l_mp,
2920 rhead->h_magicno != cpu_to_be32(XLOG_HEADER_MAGIC_NUM)))
2921 return -EFSCORRUPTED;
2922 if (XFS_IS_CORRUPT(log->l_mp,
2923 (!rhead->h_version ||
2924 (be32_to_cpu(rhead->h_version) &
2925 (~XLOG_VERSION_OKBITS))))) {
2926 xfs_warn(log->l_mp, "%s: unrecognised log version (%d).",
2927 __func__, be32_to_cpu(rhead->h_version));
2928 return -EFSCORRUPTED;
2929 }
2930
2931 /*
2932 * LR body must have data (or it wouldn't have been written)
2933 * and h_len must not be greater than LR buffer size.
2934 */
2935 hlen = be32_to_cpu(rhead->h_len);
2936 if (XFS_IS_CORRUPT(log->l_mp, hlen <= 0 || hlen > bufsize))
2937 return -EFSCORRUPTED;
2938
2939 if (XFS_IS_CORRUPT(log->l_mp,
2940 blkno > log->l_logBBsize || blkno > INT_MAX))
2941 return -EFSCORRUPTED;
2942 return 0;
2943}
2944
2945/*
2946 * Read the log from tail to head and process the log records found.
2947 * Handle the two cases where the tail and head are in the same cycle
2948 * and where the active portion of the log wraps around the end of
2949 * the physical log separately. The pass parameter is passed through
2950 * to the routines called to process the data and is not looked at
2951 * here.
2952 */
2953STATIC int
2954xlog_do_recovery_pass(
2955 struct xlog *log,
2956 xfs_daddr_t head_blk,
2957 xfs_daddr_t tail_blk,
2958 int pass,
2959 xfs_daddr_t *first_bad) /* out: first bad log rec */
2960{
2961 xlog_rec_header_t *rhead;
2962 xfs_daddr_t blk_no, rblk_no;
2963 xfs_daddr_t rhead_blk;
2964 char *offset;
2965 char *hbp, *dbp;
2966 int error = 0, h_size, h_len;
2967 int error2 = 0;
2968 int bblks, split_bblks;
2969 int hblks, split_hblks, wrapped_hblks;
2970 int i;
2971 struct hlist_head rhash[XLOG_RHASH_SIZE];
2972 LIST_HEAD (buffer_list);
2973
2974 ASSERT(head_blk != tail_blk);
2975 blk_no = rhead_blk = tail_blk;
2976
2977 for (i = 0; i < XLOG_RHASH_SIZE; i++)
2978 INIT_HLIST_HEAD(&rhash[i]);
2979
2980 /*
2981 * Read the header of the tail block and get the iclog buffer size from
2982 * h_size. Use this to tell how many sectors make up the log header.
2983 */
2984 if (xfs_has_logv2(log->l_mp)) {
2985 /*
2986 * When using variable length iclogs, read first sector of
2987 * iclog header and extract the header size from it. Get a
2988 * new hbp that is the correct size.
2989 */
2990 hbp = xlog_alloc_buffer(log, 1);
2991 if (!hbp)
2992 return -ENOMEM;
2993
2994 error = xlog_bread(log, tail_blk, 1, hbp, &offset);
2995 if (error)
2996 goto bread_err1;
2997
2998 rhead = (xlog_rec_header_t *)offset;
2999
3000 /*
3001 * xfsprogs has a bug where record length is based on lsunit but
3002 * h_size (iclog size) is hardcoded to 32k. Now that we
3003 * unconditionally CRC verify the unmount record, this means the
3004 * log buffer can be too small for the record and cause an
3005 * overrun.
3006 *
3007 * Detect this condition here. Use lsunit for the buffer size as
3008 * long as this looks like the mkfs case. Otherwise, return an
3009 * error to avoid a buffer overrun.
3010 */
3011 h_size = be32_to_cpu(rhead->h_size);
3012 h_len = be32_to_cpu(rhead->h_len);
3013 if (h_len > h_size && h_len <= log->l_mp->m_logbsize &&
3014 rhead->h_num_logops == cpu_to_be32(1)) {
3015 xfs_warn(log->l_mp,
3016 "invalid iclog size (%d bytes), using lsunit (%d bytes)",
3017 h_size, log->l_mp->m_logbsize);
3018 h_size = log->l_mp->m_logbsize;
3019 }
3020
3021 error = xlog_valid_rec_header(log, rhead, tail_blk, h_size);
3022 if (error)
3023 goto bread_err1;
3024
3025 hblks = xlog_logrec_hblks(log, rhead);
3026 if (hblks != 1) {
3027 kvfree(hbp);
3028 hbp = xlog_alloc_buffer(log, hblks);
3029 }
3030 } else {
3031 ASSERT(log->l_sectBBsize == 1);
3032 hblks = 1;
3033 hbp = xlog_alloc_buffer(log, 1);
3034 h_size = XLOG_BIG_RECORD_BSIZE;
3035 }
3036
3037 if (!hbp)
3038 return -ENOMEM;
3039 dbp = xlog_alloc_buffer(log, BTOBB(h_size));
3040 if (!dbp) {
3041 kvfree(hbp);
3042 return -ENOMEM;
3043 }
3044
3045 memset(rhash, 0, sizeof(rhash));
3046 if (tail_blk > head_blk) {
3047 /*
3048 * Perform recovery around the end of the physical log.
3049 * When the head is not on the same cycle number as the tail,
3050 * we can't do a sequential recovery.
3051 */
3052 while (blk_no < log->l_logBBsize) {
3053 /*
3054 * Check for header wrapping around physical end-of-log
3055 */
3056 offset = hbp;
3057 split_hblks = 0;
3058 wrapped_hblks = 0;
3059 if (blk_no + hblks <= log->l_logBBsize) {
3060 /* Read header in one read */
3061 error = xlog_bread(log, blk_no, hblks, hbp,
3062 &offset);
3063 if (error)
3064 goto bread_err2;
3065 } else {
3066 /* This LR is split across physical log end */
3067 if (blk_no != log->l_logBBsize) {
3068 /* some data before physical log end */
3069 ASSERT(blk_no <= INT_MAX);
3070 split_hblks = log->l_logBBsize - (int)blk_no;
3071 ASSERT(split_hblks > 0);
3072 error = xlog_bread(log, blk_no,
3073 split_hblks, hbp,
3074 &offset);
3075 if (error)
3076 goto bread_err2;
3077 }
3078
3079 /*
3080 * Note: this black magic still works with
3081 * large sector sizes (non-512) only because:
3082 * - we increased the buffer size originally
3083 * by 1 sector giving us enough extra space
3084 * for the second read;
3085 * - the log start is guaranteed to be sector
3086 * aligned;
3087 * - we read the log end (LR header start)
3088 * _first_, then the log start (LR header end)
3089 * - order is important.
3090 */
3091 wrapped_hblks = hblks - split_hblks;
3092 error = xlog_bread_noalign(log, 0,
3093 wrapped_hblks,
3094 offset + BBTOB(split_hblks));
3095 if (error)
3096 goto bread_err2;
3097 }
3098 rhead = (xlog_rec_header_t *)offset;
3099 error = xlog_valid_rec_header(log, rhead,
3100 split_hblks ? blk_no : 0, h_size);
3101 if (error)
3102 goto bread_err2;
3103
3104 bblks = (int)BTOBB(be32_to_cpu(rhead->h_len));
3105 blk_no += hblks;
3106
3107 /*
3108 * Read the log record data in multiple reads if it
3109 * wraps around the end of the log. Note that if the
3110 * header already wrapped, blk_no could point past the
3111 * end of the log. The record data is contiguous in
3112 * that case.
3113 */
3114 if (blk_no + bblks <= log->l_logBBsize ||
3115 blk_no >= log->l_logBBsize) {
3116 rblk_no = xlog_wrap_logbno(log, blk_no);
3117 error = xlog_bread(log, rblk_no, bblks, dbp,
3118 &offset);
3119 if (error)
3120 goto bread_err2;
3121 } else {
3122 /* This log record is split across the
3123 * physical end of log */
3124 offset = dbp;
3125 split_bblks = 0;
3126 if (blk_no != log->l_logBBsize) {
3127 /* some data is before the physical
3128 * end of log */
3129 ASSERT(!wrapped_hblks);
3130 ASSERT(blk_no <= INT_MAX);
3131 split_bblks =
3132 log->l_logBBsize - (int)blk_no;
3133 ASSERT(split_bblks > 0);
3134 error = xlog_bread(log, blk_no,
3135 split_bblks, dbp,
3136 &offset);
3137 if (error)
3138 goto bread_err2;
3139 }
3140
3141 /*
3142 * Note: this black magic still works with
3143 * large sector sizes (non-512) only because:
3144 * - we increased the buffer size originally
3145 * by 1 sector giving us enough extra space
3146 * for the second read;
3147 * - the log start is guaranteed to be sector
3148 * aligned;
3149 * - we read the log end (LR header start)
3150 * _first_, then the log start (LR header end)
3151 * - order is important.
3152 */
3153 error = xlog_bread_noalign(log, 0,
3154 bblks - split_bblks,
3155 offset + BBTOB(split_bblks));
3156 if (error)
3157 goto bread_err2;
3158 }
3159
3160 error = xlog_recover_process(log, rhash, rhead, offset,
3161 pass, &buffer_list);
3162 if (error)
3163 goto bread_err2;
3164
3165 blk_no += bblks;
3166 rhead_blk = blk_no;
3167 }
3168
3169 ASSERT(blk_no >= log->l_logBBsize);
3170 blk_no -= log->l_logBBsize;
3171 rhead_blk = blk_no;
3172 }
3173
3174 /* read first part of physical log */
3175 while (blk_no < head_blk) {
3176 error = xlog_bread(log, blk_no, hblks, hbp, &offset);
3177 if (error)
3178 goto bread_err2;
3179
3180 rhead = (xlog_rec_header_t *)offset;
3181 error = xlog_valid_rec_header(log, rhead, blk_no, h_size);
3182 if (error)
3183 goto bread_err2;
3184
3185 /* blocks in data section */
3186 bblks = (int)BTOBB(be32_to_cpu(rhead->h_len));
3187 error = xlog_bread(log, blk_no+hblks, bblks, dbp,
3188 &offset);
3189 if (error)
3190 goto bread_err2;
3191
3192 error = xlog_recover_process(log, rhash, rhead, offset, pass,
3193 &buffer_list);
3194 if (error)
3195 goto bread_err2;
3196
3197 blk_no += bblks + hblks;
3198 rhead_blk = blk_no;
3199 }
3200
3201 bread_err2:
3202 kvfree(dbp);
3203 bread_err1:
3204 kvfree(hbp);
3205
3206 /*
3207 * Submit buffers that have been dirtied by the last record recovered.
3208 */
3209 if (!list_empty(&buffer_list)) {
3210 if (error) {
3211 /*
3212 * If there has been an item recovery error then we
3213 * cannot allow partial checkpoint writeback to
3214 * occur. We might have multiple checkpoints with the
3215 * same start LSN in this buffer list, and partial
3216 * writeback of a checkpoint in this situation can
3217 * prevent future recovery of all the changes in the
3218 * checkpoints at this start LSN.
3219 *
3220 * Note: Shutting down the filesystem will result in the
3221 * delwri submission marking all the buffers stale,
3222 * completing them and cleaning up _XBF_LOGRECOVERY
3223 * state without doing any IO.
3224 */
3225 xlog_force_shutdown(log, SHUTDOWN_LOG_IO_ERROR);
3226 }
3227 error2 = xfs_buf_delwri_submit(&buffer_list);
3228 }
3229
3230 if (error && first_bad)
3231 *first_bad = rhead_blk;
3232
3233 /*
3234 * Transactions are freed at commit time but transactions without commit
3235 * records on disk are never committed. Free any that may be left in the
3236 * hash table.
3237 */
3238 for (i = 0; i < XLOG_RHASH_SIZE; i++) {
3239 struct hlist_node *tmp;
3240 struct xlog_recover *trans;
3241
3242 hlist_for_each_entry_safe(trans, tmp, &rhash[i], r_list)
3243 xlog_recover_free_trans(trans);
3244 }
3245
3246 return error ? error : error2;
3247}
3248
3249/*
3250 * Do the recovery of the log. We actually do this in two phases.
3251 * The two passes are necessary in order to implement the function
3252 * of cancelling a record written into the log. The first pass
3253 * determines those things which have been cancelled, and the
3254 * second pass replays log items normally except for those which
3255 * have been cancelled. The handling of the replay and cancellations
3256 * takes place in the log item type specific routines.
3257 *
3258 * The table of items which have cancel records in the log is allocated
3259 * and freed at this level, since only here do we know when all of
3260 * the log recovery has been completed.
3261 */
3262STATIC int
3263xlog_do_log_recovery(
3264 struct xlog *log,
3265 xfs_daddr_t head_blk,
3266 xfs_daddr_t tail_blk)
3267{
3268 int error;
3269
3270 ASSERT(head_blk != tail_blk);
3271
3272 /*
3273 * First do a pass to find all of the cancelled buf log items.
3274 * Store them in the buf_cancel_table for use in the second pass.
3275 */
3276 error = xlog_alloc_buf_cancel_table(log);
3277 if (error)
3278 return error;
3279
3280 error = xlog_do_recovery_pass(log, head_blk, tail_blk,
3281 XLOG_RECOVER_PASS1, NULL);
3282 if (error != 0)
3283 goto out_cancel;
3284
3285 /*
3286 * Then do a second pass to actually recover the items in the log.
3287 * When it is complete free the table of buf cancel items.
3288 */
3289 error = xlog_do_recovery_pass(log, head_blk, tail_blk,
3290 XLOG_RECOVER_PASS2, NULL);
3291 if (!error)
3292 xlog_check_buf_cancel_table(log);
3293out_cancel:
3294 xlog_free_buf_cancel_table(log);
3295 return error;
3296}
3297
3298/*
3299 * Do the actual recovery
3300 */
3301STATIC int
3302xlog_do_recover(
3303 struct xlog *log,
3304 xfs_daddr_t head_blk,
3305 xfs_daddr_t tail_blk)
3306{
3307 struct xfs_mount *mp = log->l_mp;
3308 struct xfs_buf *bp = mp->m_sb_bp;
3309 struct xfs_sb *sbp = &mp->m_sb;
3310 int error;
3311
3312 trace_xfs_log_recover(log, head_blk, tail_blk);
3313
3314 /*
3315 * First replay the images in the log.
3316 */
3317 error = xlog_do_log_recovery(log, head_blk, tail_blk);
3318 if (error)
3319 return error;
3320
3321 if (xlog_is_shutdown(log))
3322 return -EIO;
3323
3324 /*
3325 * We now update the tail_lsn since much of the recovery has completed
3326 * and there may be space available to use. If there were no extent
3327 * or iunlinks, we can free up the entire log and set the tail_lsn to
3328 * be the last_sync_lsn. This was set in xlog_find_tail to be the
3329 * lsn of the last known good LR on disk. If there are extent frees
3330 * or iunlinks they will have some entries in the AIL; so we look at
3331 * the AIL to determine how to set the tail_lsn.
3332 */
3333 xlog_assign_tail_lsn(mp);
3334
3335 /*
3336 * Now that we've finished replaying all buffer and inode updates,
3337 * re-read the superblock and reverify it.
3338 */
3339 xfs_buf_lock(bp);
3340 xfs_buf_hold(bp);
3341 error = _xfs_buf_read(bp, XBF_READ);
3342 if (error) {
3343 if (!xlog_is_shutdown(log)) {
3344 xfs_buf_ioerror_alert(bp, __this_address);
3345 ASSERT(0);
3346 }
3347 xfs_buf_relse(bp);
3348 return error;
3349 }
3350
3351 /* Convert superblock from on-disk format */
3352 xfs_sb_from_disk(sbp, bp->b_addr);
3353 xfs_buf_relse(bp);
3354
3355 /* re-initialise in-core superblock and geometry structures */
3356 mp->m_features |= xfs_sb_version_to_features(sbp);
3357 xfs_reinit_percpu_counters(mp);
3358 error = xfs_initialize_perag(mp, sbp->sb_agcount, sbp->sb_dblocks,
3359 &mp->m_maxagi);
3360 if (error) {
3361 xfs_warn(mp, "Failed post-recovery per-ag init: %d", error);
3362 return error;
3363 }
3364 mp->m_alloc_set_aside = xfs_alloc_set_aside(mp);
3365
3366 /* Normal transactions can now occur */
3367 clear_bit(XLOG_ACTIVE_RECOVERY, &log->l_opstate);
3368 return 0;
3369}
3370
3371/*
3372 * Perform recovery and re-initialize some log variables in xlog_find_tail.
3373 *
3374 * Return error or zero.
3375 */
3376int
3377xlog_recover(
3378 struct xlog *log)
3379{
3380 xfs_daddr_t head_blk, tail_blk;
3381 int error;
3382
3383 /* find the tail of the log */
3384 error = xlog_find_tail(log, &head_blk, &tail_blk);
3385 if (error)
3386 return error;
3387
3388 /*
3389 * The superblock was read before the log was available and thus the LSN
3390 * could not be verified. Check the superblock LSN against the current
3391 * LSN now that it's known.
3392 */
3393 if (xfs_has_crc(log->l_mp) &&
3394 !xfs_log_check_lsn(log->l_mp, log->l_mp->m_sb.sb_lsn))
3395 return -EINVAL;
3396
3397 if (tail_blk != head_blk) {
3398 /* There used to be a comment here:
3399 *
3400 * disallow recovery on read-only mounts. note -- mount
3401 * checks for ENOSPC and turns it into an intelligent
3402 * error message.
3403 * ...but this is no longer true. Now, unless you specify
3404 * NORECOVERY (in which case this function would never be
3405 * called), we just go ahead and recover. We do this all
3406 * under the vfs layer, so we can get away with it unless
3407 * the device itself is read-only, in which case we fail.
3408 */
3409 if ((error = xfs_dev_is_read_only(log->l_mp, "recovery"))) {
3410 return error;
3411 }
3412
3413 /*
3414 * Version 5 superblock log feature mask validation. We know the
3415 * log is dirty so check if there are any unknown log features
3416 * in what we need to recover. If there are unknown features
3417 * (e.g. unsupported transactions, then simply reject the
3418 * attempt at recovery before touching anything.
3419 */
3420 if (xfs_sb_is_v5(&log->l_mp->m_sb) &&
3421 xfs_sb_has_incompat_log_feature(&log->l_mp->m_sb,
3422 XFS_SB_FEAT_INCOMPAT_LOG_UNKNOWN)) {
3423 xfs_warn(log->l_mp,
3424"Superblock has unknown incompatible log features (0x%x) enabled.",
3425 (log->l_mp->m_sb.sb_features_log_incompat &
3426 XFS_SB_FEAT_INCOMPAT_LOG_UNKNOWN));
3427 xfs_warn(log->l_mp,
3428"The log can not be fully and/or safely recovered by this kernel.");
3429 xfs_warn(log->l_mp,
3430"Please recover the log on a kernel that supports the unknown features.");
3431 return -EINVAL;
3432 }
3433
3434 /*
3435 * Delay log recovery if the debug hook is set. This is debug
3436 * instrumentation to coordinate simulation of I/O failures with
3437 * log recovery.
3438 */
3439 if (xfs_globals.log_recovery_delay) {
3440 xfs_notice(log->l_mp,
3441 "Delaying log recovery for %d seconds.",
3442 xfs_globals.log_recovery_delay);
3443 msleep(xfs_globals.log_recovery_delay * 1000);
3444 }
3445
3446 xfs_notice(log->l_mp, "Starting recovery (logdev: %s)",
3447 log->l_mp->m_logname ? log->l_mp->m_logname
3448 : "internal");
3449
3450 error = xlog_do_recover(log, head_blk, tail_blk);
3451 set_bit(XLOG_RECOVERY_NEEDED, &log->l_opstate);
3452 }
3453 return error;
3454}
3455
3456/*
3457 * In the first part of recovery we replay inodes and buffers and build up the
3458 * list of intents which need to be processed. Here we process the intents and
3459 * clean up the on disk unlinked inode lists. This is separated from the first
3460 * part of recovery so that the root and real-time bitmap inodes can be read in
3461 * from disk in between the two stages. This is necessary so that we can free
3462 * space in the real-time portion of the file system.
3463 *
3464 * We run this whole process under GFP_NOFS allocation context. We do a
3465 * combination of non-transactional and transactional work, yet we really don't
3466 * want to recurse into the filesystem from direct reclaim during any of this
3467 * processing. This allows all the recovery code run here not to care about the
3468 * memory allocation context it is running in.
3469 */
3470int
3471xlog_recover_finish(
3472 struct xlog *log)
3473{
3474 unsigned int nofs_flags = memalloc_nofs_save();
3475 int error;
3476
3477 error = xlog_recover_process_intents(log);
3478 if (error) {
3479 /*
3480 * Cancel all the unprocessed intent items now so that we don't
3481 * leave them pinned in the AIL. This can cause the AIL to
3482 * livelock on the pinned item if anyone tries to push the AIL
3483 * (inode reclaim does this) before we get around to
3484 * xfs_log_mount_cancel.
3485 */
3486 xlog_recover_cancel_intents(log);
3487 xfs_alert(log->l_mp, "Failed to recover intents");
3488 xlog_force_shutdown(log, SHUTDOWN_LOG_IO_ERROR);
3489 goto out_error;
3490 }
3491
3492 /*
3493 * Sync the log to get all the intents out of the AIL. This isn't
3494 * absolutely necessary, but it helps in case the unlink transactions
3495 * would have problems pushing the intents out of the way.
3496 */
3497 xfs_log_force(log->l_mp, XFS_LOG_SYNC);
3498
3499 /*
3500 * Now that we've recovered the log and all the intents, we can clear
3501 * the log incompat feature bits in the superblock because there's no
3502 * longer anything to protect. We rely on the AIL push to write out the
3503 * updated superblock after everything else.
3504 */
3505 if (xfs_clear_incompat_log_features(log->l_mp)) {
3506 error = xfs_sync_sb(log->l_mp, false);
3507 if (error < 0) {
3508 xfs_alert(log->l_mp,
3509 "Failed to clear log incompat features on recovery");
3510 goto out_error;
3511 }
3512 }
3513
3514 xlog_recover_process_iunlinks(log);
3515
3516 /*
3517 * Recover any CoW staging blocks that are still referenced by the
3518 * ondisk refcount metadata. During mount there cannot be any live
3519 * staging extents as we have not permitted any user modifications.
3520 * Therefore, it is safe to free them all right now, even on a
3521 * read-only mount.
3522 */
3523 error = xfs_reflink_recover_cow(log->l_mp);
3524 if (error) {
3525 xfs_alert(log->l_mp,
3526 "Failed to recover leftover CoW staging extents, err %d.",
3527 error);
3528 /*
3529 * If we get an error here, make sure the log is shut down
3530 * but return zero so that any log items committed since the
3531 * end of intents processing can be pushed through the CIL
3532 * and AIL.
3533 */
3534 xlog_force_shutdown(log, SHUTDOWN_LOG_IO_ERROR);
3535 error = 0;
3536 goto out_error;
3537 }
3538
3539out_error:
3540 memalloc_nofs_restore(nofs_flags);
3541 return error;
3542}
3543
3544void
3545xlog_recover_cancel(
3546 struct xlog *log)
3547{
3548 if (xlog_recovery_needed(log))
3549 xlog_recover_cancel_intents(log);
3550}
3551