1 // SPDX-License-Identifier: GPL-2.0
3 * Copyright (c) 2000-2006 Silicon Graphics, Inc.
8 #include "xfs_shared.h"
9 #include "xfs_format.h"
10 #include "xfs_log_format.h"
11 #include "xfs_trans_resv.h"
14 #include "xfs_mount.h"
15 #include "xfs_defer.h"
16 #include "xfs_inode.h"
17 #include "xfs_trans.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"
29 #include "xfs_quota.h"
32 #define BLK_AVG(blk1, blk2) ((blk1+blk2) >> 1)
39 xlog_clear_stale_blocks(
44 xlog_recover_check_summary(
47 #define xlog_recover_check_summary(log)
50 xlog_do_recovery_pass(
51 struct xlog
*, xfs_daddr_t
, xfs_daddr_t
, int, xfs_daddr_t
*);
54 * Sector aligned buffer routines for buffer create/read/write/access
58 * Verify the log-relative block number and length in basic blocks are valid for
59 * an operation involving the given XFS log buffer. Returns true if the fields
60 * are valid, false otherwise.
68 if (blk_no
< 0 || blk_no
>= log
->l_logBBsize
)
70 if (bbcount
<= 0 || (blk_no
+ bbcount
) > log
->l_logBBsize
)
76 * Allocate a buffer to hold log data. The buffer needs to be able to map to
77 * a range of nbblks basic blocks at any valid offset within the log.
85 * Pass log block 0 since we don't have an addr yet, buffer will be
88 if (XFS_IS_CORRUPT(log
->l_mp
, !xlog_verify_bno(log
, 0, nbblks
))) {
89 xfs_warn(log
->l_mp
, "Invalid block length (0x%x) for buffer",
95 * We do log I/O in units of log sectors (a power-of-2 multiple of the
96 * basic block size), so we round up the requested size to accommodate
97 * the basic blocks required for complete log sectors.
99 * In addition, the buffer may be used for a non-sector-aligned block
100 * offset, in which case an I/O of the requested size could extend
101 * beyond the end of the buffer. If the requested size is only 1 basic
102 * block it will never straddle a sector boundary, so this won't be an
103 * issue. Nor will this be a problem if the log I/O is done in basic
104 * blocks (sector size 1). But otherwise we extend the buffer by one
105 * extra log sector to ensure there's space to accommodate this
108 if (nbblks
> 1 && log
->l_sectBBsize
> 1)
109 nbblks
+= log
->l_sectBBsize
;
110 nbblks
= round_up(nbblks
, log
->l_sectBBsize
);
111 return kvzalloc(BBTOB(nbblks
), GFP_KERNEL
| __GFP_RETRY_MAYFAIL
);
115 * Return the address of the start of the given block number's data
116 * in a log buffer. The buffer covers a log sector-aligned region.
118 static inline unsigned int
123 return BBTOB(blk_no
& ((xfs_daddr_t
)log
->l_sectBBsize
- 1));
136 if (XFS_IS_CORRUPT(log
->l_mp
, !xlog_verify_bno(log
, blk_no
, nbblks
))) {
138 "Invalid log block/length (0x%llx, 0x%x) for buffer",
140 return -EFSCORRUPTED
;
143 blk_no
= round_down(blk_no
, log
->l_sectBBsize
);
144 nbblks
= round_up(nbblks
, log
->l_sectBBsize
);
147 error
= xfs_rw_bdev(log
->l_targ
->bt_bdev
, log
->l_logBBstart
+ blk_no
,
148 BBTOB(nbblks
), data
, op
);
149 if (error
&& !xlog_is_shutdown(log
)) {
151 "log recovery %s I/O error at daddr 0x%llx len %d error %d",
152 op
== REQ_OP_WRITE
? "write" : "read",
153 blk_no
, nbblks
, error
);
165 return xlog_do_io(log
, blk_no
, nbblks
, data
, REQ_OP_READ
);
178 error
= xlog_do_io(log
, blk_no
, nbblks
, data
, REQ_OP_READ
);
180 *offset
= data
+ xlog_align(log
, blk_no
);
191 return xlog_do_io(log
, blk_no
, nbblks
, data
, REQ_OP_WRITE
);
196 * dump debug superblock and log record information
199 xlog_header_check_dump(
201 xlog_rec_header_t
*head
)
203 xfs_debug(mp
, "%s: SB : uuid = %pU, fmt = %d",
204 __func__
, &mp
->m_sb
.sb_uuid
, XLOG_FMT
);
205 xfs_debug(mp
, " log : uuid = %pU, fmt = %d",
206 &head
->h_fs_uuid
, be32_to_cpu(head
->h_fmt
));
209 #define xlog_header_check_dump(mp, head)
213 * check log record header for recovery
216 xlog_header_check_recover(
218 xlog_rec_header_t
*head
)
220 ASSERT(head
->h_magicno
== cpu_to_be32(XLOG_HEADER_MAGIC_NUM
));
223 * IRIX doesn't write the h_fmt field and leaves it zeroed
224 * (XLOG_FMT_UNKNOWN). This stops us from trying to recover
225 * a dirty log created in IRIX.
227 if (XFS_IS_CORRUPT(mp
, head
->h_fmt
!= cpu_to_be32(XLOG_FMT
))) {
229 "dirty log written in incompatible format - can't recover");
230 xlog_header_check_dump(mp
, head
);
231 return -EFSCORRUPTED
;
233 if (XFS_IS_CORRUPT(mp
, !uuid_equal(&mp
->m_sb
.sb_uuid
,
234 &head
->h_fs_uuid
))) {
236 "dirty log entry has mismatched uuid - can't recover");
237 xlog_header_check_dump(mp
, head
);
238 return -EFSCORRUPTED
;
244 * read the head block of the log and check the header
247 xlog_header_check_mount(
249 xlog_rec_header_t
*head
)
251 ASSERT(head
->h_magicno
== cpu_to_be32(XLOG_HEADER_MAGIC_NUM
));
253 if (uuid_is_null(&head
->h_fs_uuid
)) {
255 * IRIX doesn't write the h_fs_uuid or h_fmt fields. If
256 * h_fs_uuid is null, we assume this log was last mounted
257 * by IRIX and continue.
259 xfs_warn(mp
, "null uuid in log - IRIX style log");
260 } else if (XFS_IS_CORRUPT(mp
, !uuid_equal(&mp
->m_sb
.sb_uuid
,
261 &head
->h_fs_uuid
))) {
262 xfs_warn(mp
, "log has mismatched uuid - can't recover");
263 xlog_header_check_dump(mp
, head
);
264 return -EFSCORRUPTED
;
270 * This routine finds (to an approximation) the first block in the physical
271 * log which contains the given cycle. It uses a binary search algorithm.
272 * Note that the algorithm can not be perfect because the disk will not
273 * necessarily be perfect.
276 xlog_find_cycle_start(
279 xfs_daddr_t first_blk
,
280 xfs_daddr_t
*last_blk
,
290 mid_blk
= BLK_AVG(first_blk
, end_blk
);
291 while (mid_blk
!= first_blk
&& mid_blk
!= end_blk
) {
292 error
= xlog_bread(log
, mid_blk
, 1, buffer
, &offset
);
295 mid_cycle
= xlog_get_cycle(offset
);
296 if (mid_cycle
== cycle
)
297 end_blk
= mid_blk
; /* last_half_cycle == mid_cycle */
299 first_blk
= mid_blk
; /* first_half_cycle == mid_cycle */
300 mid_blk
= BLK_AVG(first_blk
, end_blk
);
302 ASSERT((mid_blk
== first_blk
&& mid_blk
+1 == end_blk
) ||
303 (mid_blk
== end_blk
&& mid_blk
-1 == first_blk
));
311 * Check that a range of blocks does not contain stop_on_cycle_no.
312 * Fill in *new_blk with the block offset where such a block is
313 * found, or with -1 (an invalid block number) if there is no such
314 * block in the range. The scan needs to occur from front to back
315 * and the pointer into the region must be updated since a later
316 * routine will need to perform another test.
319 xlog_find_verify_cycle(
321 xfs_daddr_t start_blk
,
323 uint stop_on_cycle_no
,
324 xfs_daddr_t
*new_blk
)
334 * Greedily allocate a buffer big enough to handle the full
335 * range of basic blocks we'll be examining. If that fails,
336 * try a smaller size. We need to be able to read at least
337 * a log sector, or we're out of luck.
339 bufblks
= 1 << ffs(nbblks
);
340 while (bufblks
> log
->l_logBBsize
)
342 while (!(buffer
= xlog_alloc_buffer(log
, bufblks
))) {
344 if (bufblks
< log
->l_sectBBsize
)
348 for (i
= start_blk
; i
< start_blk
+ nbblks
; i
+= bufblks
) {
351 bcount
= min(bufblks
, (start_blk
+ nbblks
- i
));
353 error
= xlog_bread(log
, i
, bcount
, buffer
, &buf
);
357 for (j
= 0; j
< bcount
; j
++) {
358 cycle
= xlog_get_cycle(buf
);
359 if (cycle
== stop_on_cycle_no
) {
376 xlog_logrec_hblks(struct xlog
*log
, struct xlog_rec_header
*rh
)
378 if (xfs_has_logv2(log
->l_mp
)) {
379 int h_size
= be32_to_cpu(rh
->h_size
);
381 if ((be32_to_cpu(rh
->h_version
) & XLOG_VERSION_2
) &&
382 h_size
> XLOG_HEADER_CYCLE_SIZE
)
383 return DIV_ROUND_UP(h_size
, XLOG_HEADER_CYCLE_SIZE
);
389 * Potentially backup over partial log record write.
391 * In the typical case, last_blk is the number of the block directly after
392 * a good log record. Therefore, we subtract one to get the block number
393 * of the last block in the given buffer. extra_bblks contains the number
394 * of blocks we would have read on a previous read. This happens when the
395 * last log record is split over the end of the physical log.
397 * extra_bblks is the number of blocks potentially verified on a previous
398 * call to this routine.
401 xlog_find_verify_log_record(
403 xfs_daddr_t start_blk
,
404 xfs_daddr_t
*last_blk
,
410 xlog_rec_header_t
*head
= NULL
;
413 int num_blks
= *last_blk
- start_blk
;
416 ASSERT(start_blk
!= 0 || *last_blk
!= start_blk
);
418 buffer
= xlog_alloc_buffer(log
, num_blks
);
420 buffer
= xlog_alloc_buffer(log
, 1);
425 error
= xlog_bread(log
, start_blk
, num_blks
, buffer
, &offset
);
428 offset
+= ((num_blks
- 1) << BBSHIFT
);
431 for (i
= (*last_blk
) - 1; i
>= 0; i
--) {
433 /* valid log record not found */
435 "Log inconsistent (didn't find previous header)");
437 error
= -EFSCORRUPTED
;
442 error
= xlog_bread(log
, i
, 1, buffer
, &offset
);
447 head
= (xlog_rec_header_t
*)offset
;
449 if (head
->h_magicno
== cpu_to_be32(XLOG_HEADER_MAGIC_NUM
))
457 * We hit the beginning of the physical log & still no header. Return
458 * to caller. If caller can handle a return of -1, then this routine
459 * will be called again for the end of the physical log.
467 * We have the final block of the good log (the first block
468 * of the log record _before_ the head. So we check the uuid.
470 if ((error
= xlog_header_check_mount(log
->l_mp
, head
)))
474 * We may have found a log record header before we expected one.
475 * last_blk will be the 1st block # with a given cycle #. We may end
476 * up reading an entire log record. In this case, we don't want to
477 * reset last_blk. Only when last_blk points in the middle of a log
478 * record do we update last_blk.
480 xhdrs
= xlog_logrec_hblks(log
, head
);
482 if (*last_blk
- i
+ extra_bblks
!=
483 BTOBB(be32_to_cpu(head
->h_len
)) + xhdrs
)
492 * Head is defined to be the point of the log where the next log write
493 * could go. This means that incomplete LR writes at the end are
494 * eliminated when calculating the head. We aren't guaranteed that previous
495 * LR have complete transactions. We only know that a cycle number of
496 * current cycle number -1 won't be present in the log if we start writing
497 * from our current block number.
499 * last_blk contains the block number of the first block with a given
502 * Return: zero if normal, non-zero if error.
507 xfs_daddr_t
*return_head_blk
)
511 xfs_daddr_t new_blk
, first_blk
, start_blk
, last_blk
, head_blk
;
513 uint first_half_cycle
, last_half_cycle
;
515 int error
, log_bbnum
= log
->l_logBBsize
;
517 /* Is the end of the log device zeroed? */
518 error
= xlog_find_zeroed(log
, &first_blk
);
520 xfs_warn(log
->l_mp
, "empty log check failed");
524 *return_head_blk
= first_blk
;
526 /* Is the whole lot zeroed? */
528 /* Linux XFS shouldn't generate totally zeroed logs -
529 * mkfs etc write a dummy unmount record to a fresh
530 * log so we can store the uuid in there
532 xfs_warn(log
->l_mp
, "totally zeroed log");
538 first_blk
= 0; /* get cycle # of 1st block */
539 buffer
= xlog_alloc_buffer(log
, 1);
543 error
= xlog_bread(log
, 0, 1, buffer
, &offset
);
545 goto out_free_buffer
;
547 first_half_cycle
= xlog_get_cycle(offset
);
549 last_blk
= head_blk
= log_bbnum
- 1; /* get cycle # of last block */
550 error
= xlog_bread(log
, last_blk
, 1, buffer
, &offset
);
552 goto out_free_buffer
;
554 last_half_cycle
= xlog_get_cycle(offset
);
555 ASSERT(last_half_cycle
!= 0);
558 * If the 1st half cycle number is equal to the last half cycle number,
559 * then the entire log is stamped with the same cycle number. In this
560 * case, head_blk can't be set to zero (which makes sense). The below
561 * math doesn't work out properly with head_blk equal to zero. Instead,
562 * we set it to log_bbnum which is an invalid block number, but this
563 * value makes the math correct. If head_blk doesn't changed through
564 * all the tests below, *head_blk is set to zero at the very end rather
565 * than log_bbnum. In a sense, log_bbnum and zero are the same block
566 * in a circular file.
568 if (first_half_cycle
== last_half_cycle
) {
570 * In this case we believe that the entire log should have
571 * cycle number last_half_cycle. We need to scan backwards
572 * from the end verifying that there are no holes still
573 * containing last_half_cycle - 1. If we find such a hole,
574 * then the start of that hole will be the new head. The
575 * simple case looks like
576 * x | x ... | x - 1 | x
577 * Another case that fits this picture would be
578 * x | x + 1 | x ... | x
579 * In this case the head really is somewhere at the end of the
580 * log, as one of the latest writes at the beginning was
583 * x | x + 1 | x ... | x - 1 | x
584 * This is really the combination of the above two cases, and
585 * the head has to end up at the start of the x-1 hole at the
588 * In the 256k log case, we will read from the beginning to the
589 * end of the log and search for cycle numbers equal to x-1.
590 * We don't worry about the x+1 blocks that we encounter,
591 * because we know that they cannot be the head since the log
594 head_blk
= log_bbnum
;
595 stop_on_cycle
= last_half_cycle
- 1;
598 * In this case we want to find the first block with cycle
599 * number matching last_half_cycle. We expect the log to be
601 * x + 1 ... | x ... | x
602 * The first block with cycle number x (last_half_cycle) will
603 * be where the new head belongs. First we do a binary search
604 * for the first occurrence of last_half_cycle. The binary
605 * search may not be totally accurate, so then we scan back
606 * from there looking for occurrences of last_half_cycle before
607 * us. If that backwards scan wraps around the beginning of
608 * the log, then we look for occurrences of last_half_cycle - 1
609 * at the end of the log. The cases we're looking for look
611 * v binary search stopped here
612 * x + 1 ... | x | x + 1 | x ... | x
613 * ^ but we want to locate this spot
615 * <---------> less than scan distance
616 * x + 1 ... | x ... | x - 1 | x
617 * ^ we want to locate this spot
619 stop_on_cycle
= last_half_cycle
;
620 error
= xlog_find_cycle_start(log
, buffer
, first_blk
, &head_blk
,
623 goto out_free_buffer
;
627 * Now validate the answer. Scan back some number of maximum possible
628 * blocks and make sure each one has the expected cycle number. The
629 * maximum is determined by the total possible amount of buffering
630 * in the in-core log. The following number can be made tighter if
631 * we actually look at the block size of the filesystem.
633 num_scan_bblks
= min_t(int, log_bbnum
, XLOG_TOTAL_REC_SHIFT(log
));
634 if (head_blk
>= num_scan_bblks
) {
636 * We are guaranteed that the entire check can be performed
639 start_blk
= head_blk
- num_scan_bblks
;
640 if ((error
= xlog_find_verify_cycle(log
,
641 start_blk
, num_scan_bblks
,
642 stop_on_cycle
, &new_blk
)))
643 goto out_free_buffer
;
646 } else { /* need to read 2 parts of log */
648 * We are going to scan backwards in the log in two parts.
649 * First we scan the physical end of the log. In this part
650 * of the log, we are looking for blocks with cycle number
651 * last_half_cycle - 1.
652 * If we find one, then we know that the log starts there, as
653 * we've found a hole that didn't get written in going around
654 * the end of the physical log. The simple case for this is
655 * x + 1 ... | x ... | x - 1 | x
656 * <---------> less than scan distance
657 * If all of the blocks at the end of the log have cycle number
658 * last_half_cycle, then we check the blocks at the start of
659 * the log looking for occurrences of last_half_cycle. If we
660 * find one, then our current estimate for the location of the
661 * first occurrence of last_half_cycle is wrong and we move
662 * back to the hole we've found. This case looks like
663 * x + 1 ... | x | x + 1 | x ...
664 * ^ binary search stopped here
665 * Another case we need to handle that only occurs in 256k
667 * x + 1 ... | x ... | x+1 | x ...
668 * ^ binary search stops here
669 * In a 256k log, the scan at the end of the log will see the
670 * x + 1 blocks. We need to skip past those since that is
671 * certainly not the head of the log. By searching for
672 * last_half_cycle-1 we accomplish that.
674 ASSERT(head_blk
<= INT_MAX
&&
675 (xfs_daddr_t
) num_scan_bblks
>= head_blk
);
676 start_blk
= log_bbnum
- (num_scan_bblks
- head_blk
);
677 if ((error
= xlog_find_verify_cycle(log
, start_blk
,
678 num_scan_bblks
- (int)head_blk
,
679 (stop_on_cycle
- 1), &new_blk
)))
680 goto out_free_buffer
;
687 * Scan beginning of log now. The last part of the physical
688 * log is good. This scan needs to verify that it doesn't find
689 * the last_half_cycle.
692 ASSERT(head_blk
<= INT_MAX
);
693 if ((error
= xlog_find_verify_cycle(log
,
694 start_blk
, (int)head_blk
,
695 stop_on_cycle
, &new_blk
)))
696 goto out_free_buffer
;
703 * Now we need to make sure head_blk is not pointing to a block in
704 * the middle of a log record.
706 num_scan_bblks
= XLOG_REC_SHIFT(log
);
707 if (head_blk
>= num_scan_bblks
) {
708 start_blk
= head_blk
- num_scan_bblks
; /* don't read head_blk */
710 /* start ptr at last block ptr before head_blk */
711 error
= xlog_find_verify_log_record(log
, start_blk
, &head_blk
, 0);
715 goto out_free_buffer
;
718 ASSERT(head_blk
<= INT_MAX
);
719 error
= xlog_find_verify_log_record(log
, start_blk
, &head_blk
, 0);
721 goto out_free_buffer
;
723 /* We hit the beginning of the log during our search */
724 start_blk
= log_bbnum
- (num_scan_bblks
- head_blk
);
726 ASSERT(start_blk
<= INT_MAX
&&
727 (xfs_daddr_t
) log_bbnum
-start_blk
>= 0);
728 ASSERT(head_blk
<= INT_MAX
);
729 error
= xlog_find_verify_log_record(log
, start_blk
,
730 &new_blk
, (int)head_blk
);
734 goto out_free_buffer
;
735 if (new_blk
!= log_bbnum
)
738 goto out_free_buffer
;
742 if (head_blk
== log_bbnum
)
743 *return_head_blk
= 0;
745 *return_head_blk
= head_blk
;
747 * When returning here, we have a good block number. Bad block
748 * means that during a previous crash, we didn't have a clean break
749 * from cycle number N to cycle number N-1. In this case, we need
750 * to find the first block with cycle number N-1.
757 xfs_warn(log
->l_mp
, "failed to find log head");
762 * Seek backwards in the log for log record headers.
764 * Given a starting log block, walk backwards until we find the provided number
765 * of records or hit the provided tail block. The return value is the number of
766 * records encountered or a negative error code. The log block and buffer
767 * pointer of the last record seen are returned in rblk and rhead respectively.
770 xlog_rseek_logrec_hdr(
772 xfs_daddr_t head_blk
,
773 xfs_daddr_t tail_blk
,
777 struct xlog_rec_header
**rhead
,
789 * Walk backwards from the head block until we hit the tail or the first
792 end_blk
= head_blk
> tail_blk
? tail_blk
: 0;
793 for (i
= (int) head_blk
- 1; i
>= end_blk
; i
--) {
794 error
= xlog_bread(log
, i
, 1, buffer
, &offset
);
798 if (*(__be32
*) offset
== cpu_to_be32(XLOG_HEADER_MAGIC_NUM
)) {
800 *rhead
= (struct xlog_rec_header
*) offset
;
801 if (++found
== count
)
807 * If we haven't hit the tail block or the log record header count,
808 * start looking again from the end of the physical log. Note that
809 * callers can pass head == tail if the tail is not yet known.
811 if (tail_blk
>= head_blk
&& found
!= count
) {
812 for (i
= log
->l_logBBsize
- 1; i
>= (int) tail_blk
; i
--) {
813 error
= xlog_bread(log
, i
, 1, buffer
, &offset
);
817 if (*(__be32
*)offset
==
818 cpu_to_be32(XLOG_HEADER_MAGIC_NUM
)) {
821 *rhead
= (struct xlog_rec_header
*) offset
;
822 if (++found
== count
)
835 * Seek forward in the log for log record headers.
837 * Given head and tail blocks, walk forward from the tail block until we find
838 * the provided number of records or hit the head block. The return value is the
839 * number of records encountered or a negative error code. The log block and
840 * buffer pointer of the last record seen are returned in rblk and rhead
844 xlog_seek_logrec_hdr(
846 xfs_daddr_t head_blk
,
847 xfs_daddr_t tail_blk
,
851 struct xlog_rec_header
**rhead
,
863 * Walk forward from the tail block until we hit the head or the last
866 end_blk
= head_blk
> tail_blk
? head_blk
: log
->l_logBBsize
- 1;
867 for (i
= (int) tail_blk
; i
<= end_blk
; i
++) {
868 error
= xlog_bread(log
, i
, 1, buffer
, &offset
);
872 if (*(__be32
*) offset
== cpu_to_be32(XLOG_HEADER_MAGIC_NUM
)) {
874 *rhead
= (struct xlog_rec_header
*) offset
;
875 if (++found
== count
)
881 * If we haven't hit the head block or the log record header count,
882 * start looking again from the start of the physical log.
884 if (tail_blk
> head_blk
&& found
!= count
) {
885 for (i
= 0; i
< (int) head_blk
; i
++) {
886 error
= xlog_bread(log
, i
, 1, buffer
, &offset
);
890 if (*(__be32
*)offset
==
891 cpu_to_be32(XLOG_HEADER_MAGIC_NUM
)) {
894 *rhead
= (struct xlog_rec_header
*) offset
;
895 if (++found
== count
)
908 * Calculate distance from head to tail (i.e., unused space in the log).
913 xfs_daddr_t head_blk
,
914 xfs_daddr_t tail_blk
)
916 if (head_blk
< tail_blk
)
917 return tail_blk
- head_blk
;
919 return tail_blk
+ (log
->l_logBBsize
- head_blk
);
923 * Verify the log tail. This is particularly important when torn or incomplete
924 * writes have been detected near the front of the log and the head has been
925 * walked back accordingly.
927 * We also have to handle the case where the tail was pinned and the head
928 * blocked behind the tail right before a crash. If the tail had been pushed
929 * immediately prior to the crash and the subsequent checkpoint was only
930 * partially written, it's possible it overwrote the last referenced tail in the
931 * log with garbage. This is not a coherency problem because the tail must have
932 * been pushed before it can be overwritten, but appears as log corruption to
933 * recovery because we have no way to know the tail was updated if the
934 * subsequent checkpoint didn't write successfully.
936 * Therefore, CRC check the log from tail to head. If a failure occurs and the
937 * offending record is within max iclog bufs from the head, walk the tail
938 * forward and retry until a valid tail is found or corruption is detected out
939 * of the range of a possible overwrite.
944 xfs_daddr_t head_blk
,
945 xfs_daddr_t
*tail_blk
,
948 struct xlog_rec_header
*thead
;
950 xfs_daddr_t first_bad
;
953 xfs_daddr_t tmp_tail
;
954 xfs_daddr_t orig_tail
= *tail_blk
;
956 buffer
= xlog_alloc_buffer(log
, 1);
961 * Make sure the tail points to a record (returns positive count on
964 error
= xlog_seek_logrec_hdr(log
, head_blk
, *tail_blk
, 1, buffer
,
965 &tmp_tail
, &thead
, &wrapped
);
968 if (*tail_blk
!= tmp_tail
)
969 *tail_blk
= tmp_tail
;
972 * Run a CRC check from the tail to the head. We can't just check
973 * MAX_ICLOGS records past the tail because the tail may point to stale
974 * blocks cleared during the search for the head/tail. These blocks are
975 * overwritten with zero-length records and thus record count is not a
976 * reliable indicator of the iclog state before a crash.
979 error
= xlog_do_recovery_pass(log
, head_blk
, *tail_blk
,
980 XLOG_RECOVER_CRCPASS
, &first_bad
);
981 while ((error
== -EFSBADCRC
|| error
== -EFSCORRUPTED
) && first_bad
) {
985 * Is corruption within range of the head? If so, retry from
986 * the next record. Otherwise return an error.
988 tail_distance
= xlog_tail_distance(log
, head_blk
, first_bad
);
989 if (tail_distance
> BTOBB(XLOG_MAX_ICLOGS
* hsize
))
992 /* skip to the next record; returns positive count on success */
993 error
= xlog_seek_logrec_hdr(log
, head_blk
, first_bad
, 2,
994 buffer
, &tmp_tail
, &thead
, &wrapped
);
998 *tail_blk
= tmp_tail
;
1000 error
= xlog_do_recovery_pass(log
, head_blk
, *tail_blk
,
1001 XLOG_RECOVER_CRCPASS
, &first_bad
);
1004 if (!error
&& *tail_blk
!= orig_tail
)
1006 "Tail block (0x%llx) overwrite detected. Updated to 0x%llx",
1007 orig_tail
, *tail_blk
);
1014 * Detect and trim torn writes from the head of the log.
1016 * Storage without sector atomicity guarantees can result in torn writes in the
1017 * log in the event of a crash. Our only means to detect this scenario is via
1018 * CRC verification. While we can't always be certain that CRC verification
1019 * failure is due to a torn write vs. an unrelated corruption, we do know that
1020 * only a certain number (XLOG_MAX_ICLOGS) of log records can be written out at
1021 * one time. Therefore, CRC verify up to XLOG_MAX_ICLOGS records at the head of
1022 * the log and treat failures in this range as torn writes as a matter of
1023 * policy. In the event of CRC failure, the head is walked back to the last good
1024 * record in the log and the tail is updated from that record and verified.
1029 xfs_daddr_t
*head_blk
, /* in/out: unverified head */
1030 xfs_daddr_t
*tail_blk
, /* out: tail block */
1032 xfs_daddr_t
*rhead_blk
, /* start blk of last record */
1033 struct xlog_rec_header
**rhead
, /* ptr to last record */
1034 bool *wrapped
) /* last rec. wraps phys. log */
1036 struct xlog_rec_header
*tmp_rhead
;
1038 xfs_daddr_t first_bad
;
1039 xfs_daddr_t tmp_rhead_blk
;
1045 * Check the head of the log for torn writes. Search backwards from the
1046 * head until we hit the tail or the maximum number of log record I/Os
1047 * that could have been in flight at one time. Use a temporary buffer so
1048 * we don't trash the rhead/buffer pointers from the caller.
1050 tmp_buffer
= xlog_alloc_buffer(log
, 1);
1053 error
= xlog_rseek_logrec_hdr(log
, *head_blk
, *tail_blk
,
1054 XLOG_MAX_ICLOGS
, tmp_buffer
,
1055 &tmp_rhead_blk
, &tmp_rhead
, &tmp_wrapped
);
1056 kmem_free(tmp_buffer
);
1061 * Now run a CRC verification pass over the records starting at the
1062 * block found above to the current head. If a CRC failure occurs, the
1063 * log block of the first bad record is saved in first_bad.
1065 error
= xlog_do_recovery_pass(log
, *head_blk
, tmp_rhead_blk
,
1066 XLOG_RECOVER_CRCPASS
, &first_bad
);
1067 if ((error
== -EFSBADCRC
|| error
== -EFSCORRUPTED
) && first_bad
) {
1069 * We've hit a potential torn write. Reset the error and warn
1074 "Torn write (CRC failure) detected at log block 0x%llx. Truncating head block from 0x%llx.",
1075 first_bad
, *head_blk
);
1078 * Get the header block and buffer pointer for the last good
1079 * record before the bad record.
1081 * Note that xlog_find_tail() clears the blocks at the new head
1082 * (i.e., the records with invalid CRC) if the cycle number
1083 * matches the current cycle.
1085 found
= xlog_rseek_logrec_hdr(log
, first_bad
, *tail_blk
, 1,
1086 buffer
, rhead_blk
, rhead
, wrapped
);
1089 if (found
== 0) /* XXX: right thing to do here? */
1093 * Reset the head block to the starting block of the first bad
1094 * log record and set the tail block based on the last good
1097 * Bail out if the updated head/tail match as this indicates
1098 * possible corruption outside of the acceptable
1099 * (XLOG_MAX_ICLOGS) range. This is a job for xfs_repair...
1101 *head_blk
= first_bad
;
1102 *tail_blk
= BLOCK_LSN(be64_to_cpu((*rhead
)->h_tail_lsn
));
1103 if (*head_blk
== *tail_blk
) {
1111 return xlog_verify_tail(log
, *head_blk
, tail_blk
,
1112 be32_to_cpu((*rhead
)->h_size
));
1116 * We need to make sure we handle log wrapping properly, so we can't use the
1117 * calculated logbno directly. Make sure it wraps to the correct bno inside the
1120 * The log is limited to 32 bit sizes, so we use the appropriate modulus
1121 * operation here and cast it back to a 64 bit daddr on return.
1123 static inline xfs_daddr_t
1130 div_s64_rem(bno
, log
->l_logBBsize
, &mod
);
1135 * Check whether the head of the log points to an unmount record. In other
1136 * words, determine whether the log is clean. If so, update the in-core state
1140 xlog_check_unmount_rec(
1142 xfs_daddr_t
*head_blk
,
1143 xfs_daddr_t
*tail_blk
,
1144 struct xlog_rec_header
*rhead
,
1145 xfs_daddr_t rhead_blk
,
1149 struct xlog_op_header
*op_head
;
1150 xfs_daddr_t umount_data_blk
;
1151 xfs_daddr_t after_umount_blk
;
1159 * Look for unmount record. If we find it, then we know there was a
1160 * clean unmount. Since 'i' could be the last block in the physical
1161 * log, we convert to a log block before comparing to the head_blk.
1163 * Save the current tail lsn to use to pass to xlog_clear_stale_blocks()
1164 * below. We won't want to clear the unmount record if there is one, so
1165 * we pass the lsn of the unmount record rather than the block after it.
1167 hblks
= xlog_logrec_hblks(log
, rhead
);
1168 after_umount_blk
= xlog_wrap_logbno(log
,
1169 rhead_blk
+ hblks
+ BTOBB(be32_to_cpu(rhead
->h_len
)));
1171 if (*head_blk
== after_umount_blk
&&
1172 be32_to_cpu(rhead
->h_num_logops
) == 1) {
1173 umount_data_blk
= xlog_wrap_logbno(log
, rhead_blk
+ hblks
);
1174 error
= xlog_bread(log
, umount_data_blk
, 1, buffer
, &offset
);
1178 op_head
= (struct xlog_op_header
*)offset
;
1179 if (op_head
->oh_flags
& XLOG_UNMOUNT_TRANS
) {
1181 * Set tail and last sync so that newly written log
1182 * records will point recovery to after the current
1185 xlog_assign_atomic_lsn(&log
->l_tail_lsn
,
1186 log
->l_curr_cycle
, after_umount_blk
);
1187 xlog_assign_atomic_lsn(&log
->l_last_sync_lsn
,
1188 log
->l_curr_cycle
, after_umount_blk
);
1189 *tail_blk
= after_umount_blk
;
1201 xfs_daddr_t head_blk
,
1202 struct xlog_rec_header
*rhead
,
1203 xfs_daddr_t rhead_blk
,
1207 * Reset log values according to the state of the log when we
1208 * crashed. In the case where head_blk == 0, we bump curr_cycle
1209 * one because the next write starts a new cycle rather than
1210 * continuing the cycle of the last good log record. At this
1211 * point we have guaranteed that all partial log records have been
1212 * accounted for. Therefore, we know that the last good log record
1213 * written was complete and ended exactly on the end boundary
1214 * of the physical log.
1216 log
->l_prev_block
= rhead_blk
;
1217 log
->l_curr_block
= (int)head_blk
;
1218 log
->l_curr_cycle
= be32_to_cpu(rhead
->h_cycle
);
1220 log
->l_curr_cycle
++;
1221 atomic64_set(&log
->l_tail_lsn
, be64_to_cpu(rhead
->h_tail_lsn
));
1222 atomic64_set(&log
->l_last_sync_lsn
, be64_to_cpu(rhead
->h_lsn
));
1223 xlog_assign_grant_head(&log
->l_reserve_head
.grant
, log
->l_curr_cycle
,
1224 BBTOB(log
->l_curr_block
));
1225 xlog_assign_grant_head(&log
->l_write_head
.grant
, log
->l_curr_cycle
,
1226 BBTOB(log
->l_curr_block
));
1230 * Find the sync block number or the tail of the log.
1232 * This will be the block number of the last record to have its
1233 * associated buffers synced to disk. Every log record header has
1234 * a sync lsn embedded in it. LSNs hold block numbers, so it is easy
1235 * to get a sync block number. The only concern is to figure out which
1236 * log record header to believe.
1238 * The following algorithm uses the log record header with the largest
1239 * lsn. The entire log record does not need to be valid. We only care
1240 * that the header is valid.
1242 * We could speed up search by using current head_blk buffer, but it is not
1248 xfs_daddr_t
*head_blk
,
1249 xfs_daddr_t
*tail_blk
)
1251 xlog_rec_header_t
*rhead
;
1252 char *offset
= NULL
;
1255 xfs_daddr_t rhead_blk
;
1257 bool wrapped
= false;
1261 * Find previous log record
1263 if ((error
= xlog_find_head(log
, head_blk
)))
1265 ASSERT(*head_blk
< INT_MAX
);
1267 buffer
= xlog_alloc_buffer(log
, 1);
1270 if (*head_blk
== 0) { /* special case */
1271 error
= xlog_bread(log
, 0, 1, buffer
, &offset
);
1275 if (xlog_get_cycle(offset
) == 0) {
1277 /* leave all other log inited values alone */
1283 * Search backwards through the log looking for the log record header
1284 * block. This wraps all the way back around to the head so something is
1285 * seriously wrong if we can't find it.
1287 error
= xlog_rseek_logrec_hdr(log
, *head_blk
, *head_blk
, 1, buffer
,
1288 &rhead_blk
, &rhead
, &wrapped
);
1292 xfs_warn(log
->l_mp
, "%s: couldn't find sync record", __func__
);
1293 error
= -EFSCORRUPTED
;
1296 *tail_blk
= BLOCK_LSN(be64_to_cpu(rhead
->h_tail_lsn
));
1299 * Set the log state based on the current head record.
1301 xlog_set_state(log
, *head_blk
, rhead
, rhead_blk
, wrapped
);
1302 tail_lsn
= atomic64_read(&log
->l_tail_lsn
);
1305 * Look for an unmount record at the head of the log. This sets the log
1306 * state to determine whether recovery is necessary.
1308 error
= xlog_check_unmount_rec(log
, head_blk
, tail_blk
, rhead
,
1309 rhead_blk
, buffer
, &clean
);
1314 * Verify the log head if the log is not clean (e.g., we have anything
1315 * but an unmount record at the head). This uses CRC verification to
1316 * detect and trim torn writes. If discovered, CRC failures are
1317 * considered torn writes and the log head is trimmed accordingly.
1319 * Note that we can only run CRC verification when the log is dirty
1320 * because there's no guarantee that the log data behind an unmount
1321 * record is compatible with the current architecture.
1324 xfs_daddr_t orig_head
= *head_blk
;
1326 error
= xlog_verify_head(log
, head_blk
, tail_blk
, buffer
,
1327 &rhead_blk
, &rhead
, &wrapped
);
1331 /* update in-core state again if the head changed */
1332 if (*head_blk
!= orig_head
) {
1333 xlog_set_state(log
, *head_blk
, rhead
, rhead_blk
,
1335 tail_lsn
= atomic64_read(&log
->l_tail_lsn
);
1336 error
= xlog_check_unmount_rec(log
, head_blk
, tail_blk
,
1337 rhead
, rhead_blk
, buffer
,
1345 * Note that the unmount was clean. If the unmount was not clean, we
1346 * need to know this to rebuild the superblock counters from the perag
1347 * headers if we have a filesystem using non-persistent counters.
1350 set_bit(XFS_OPSTATE_CLEAN
, &log
->l_mp
->m_opstate
);
1353 * Make sure that there are no blocks in front of the head
1354 * with the same cycle number as the head. This can happen
1355 * because we allow multiple outstanding log writes concurrently,
1356 * and the later writes might make it out before earlier ones.
1358 * We use the lsn from before modifying it so that we'll never
1359 * overwrite the unmount record after a clean unmount.
1361 * Do this only if we are going to recover the filesystem
1363 * NOTE: This used to say "if (!readonly)"
1364 * However on Linux, we can & do recover a read-only filesystem.
1365 * We only skip recovery if NORECOVERY is specified on mount,
1366 * in which case we would not be here.
1368 * But... if the -device- itself is readonly, just skip this.
1369 * We can't recover this device anyway, so it won't matter.
1371 if (!xfs_readonly_buftarg(log
->l_targ
))
1372 error
= xlog_clear_stale_blocks(log
, tail_lsn
);
1378 xfs_warn(log
->l_mp
, "failed to locate log tail");
1383 * Is the log zeroed at all?
1385 * The last binary search should be changed to perform an X block read
1386 * once X becomes small enough. You can then search linearly through
1387 * the X blocks. This will cut down on the number of reads we need to do.
1389 * If the log is partially zeroed, this routine will pass back the blkno
1390 * of the first block with cycle number 0. It won't have a complete LR
1394 * 0 => the log is completely written to
1395 * 1 => use *blk_no as the first block of the log
1396 * <0 => error has occurred
1401 xfs_daddr_t
*blk_no
)
1405 uint first_cycle
, last_cycle
;
1406 xfs_daddr_t new_blk
, last_blk
, start_blk
;
1407 xfs_daddr_t num_scan_bblks
;
1408 int error
, log_bbnum
= log
->l_logBBsize
;
1412 /* check totally zeroed log */
1413 buffer
= xlog_alloc_buffer(log
, 1);
1416 error
= xlog_bread(log
, 0, 1, buffer
, &offset
);
1418 goto out_free_buffer
;
1420 first_cycle
= xlog_get_cycle(offset
);
1421 if (first_cycle
== 0) { /* completely zeroed log */
1427 /* check partially zeroed log */
1428 error
= xlog_bread(log
, log_bbnum
-1, 1, buffer
, &offset
);
1430 goto out_free_buffer
;
1432 last_cycle
= xlog_get_cycle(offset
);
1433 if (last_cycle
!= 0) { /* log completely written to */
1438 /* we have a partially zeroed log */
1439 last_blk
= log_bbnum
-1;
1440 error
= xlog_find_cycle_start(log
, buffer
, 0, &last_blk
, 0);
1442 goto out_free_buffer
;
1445 * Validate the answer. Because there is no way to guarantee that
1446 * the entire log is made up of log records which are the same size,
1447 * we scan over the defined maximum blocks. At this point, the maximum
1448 * is not chosen to mean anything special. XXXmiken
1450 num_scan_bblks
= XLOG_TOTAL_REC_SHIFT(log
);
1451 ASSERT(num_scan_bblks
<= INT_MAX
);
1453 if (last_blk
< num_scan_bblks
)
1454 num_scan_bblks
= last_blk
;
1455 start_blk
= last_blk
- num_scan_bblks
;
1458 * We search for any instances of cycle number 0 that occur before
1459 * our current estimate of the head. What we're trying to detect is
1460 * 1 ... | 0 | 1 | 0...
1461 * ^ binary search ends here
1463 if ((error
= xlog_find_verify_cycle(log
, start_blk
,
1464 (int)num_scan_bblks
, 0, &new_blk
)))
1465 goto out_free_buffer
;
1470 * Potentially backup over partial log record write. We don't need
1471 * to search the end of the log because we know it is zero.
1473 error
= xlog_find_verify_log_record(log
, start_blk
, &last_blk
, 0);
1477 goto out_free_buffer
;
1488 * These are simple subroutines used by xlog_clear_stale_blocks() below
1489 * to initialize a buffer full of empty log record headers and write
1490 * them into the log.
1501 xlog_rec_header_t
*recp
= (xlog_rec_header_t
*)buf
;
1503 memset(buf
, 0, BBSIZE
);
1504 recp
->h_magicno
= cpu_to_be32(XLOG_HEADER_MAGIC_NUM
);
1505 recp
->h_cycle
= cpu_to_be32(cycle
);
1506 recp
->h_version
= cpu_to_be32(
1507 xfs_has_logv2(log
->l_mp
) ? 2 : 1);
1508 recp
->h_lsn
= cpu_to_be64(xlog_assign_lsn(cycle
, block
));
1509 recp
->h_tail_lsn
= cpu_to_be64(xlog_assign_lsn(tail_cycle
, tail_block
));
1510 recp
->h_fmt
= cpu_to_be32(XLOG_FMT
);
1511 memcpy(&recp
->h_fs_uuid
, &log
->l_mp
->m_sb
.sb_uuid
, sizeof(uuid_t
));
1515 xlog_write_log_records(
1526 int sectbb
= log
->l_sectBBsize
;
1527 int end_block
= start_block
+ blocks
;
1533 * Greedily allocate a buffer big enough to handle the full
1534 * range of basic blocks to be written. If that fails, try
1535 * a smaller size. We need to be able to write at least a
1536 * log sector, or we're out of luck.
1538 bufblks
= 1 << ffs(blocks
);
1539 while (bufblks
> log
->l_logBBsize
)
1541 while (!(buffer
= xlog_alloc_buffer(log
, bufblks
))) {
1543 if (bufblks
< sectbb
)
1547 /* We may need to do a read at the start to fill in part of
1548 * the buffer in the starting sector not covered by the first
1551 balign
= round_down(start_block
, sectbb
);
1552 if (balign
!= start_block
) {
1553 error
= xlog_bread_noalign(log
, start_block
, 1, buffer
);
1555 goto out_free_buffer
;
1557 j
= start_block
- balign
;
1560 for (i
= start_block
; i
< end_block
; i
+= bufblks
) {
1561 int bcount
, endcount
;
1563 bcount
= min(bufblks
, end_block
- start_block
);
1564 endcount
= bcount
- j
;
1566 /* We may need to do a read at the end to fill in part of
1567 * the buffer in the final sector not covered by the write.
1568 * If this is the same sector as the above read, skip it.
1570 ealign
= round_down(end_block
, sectbb
);
1571 if (j
== 0 && (start_block
+ endcount
> ealign
)) {
1572 error
= xlog_bread_noalign(log
, ealign
, sectbb
,
1573 buffer
+ BBTOB(ealign
- start_block
));
1579 offset
= buffer
+ xlog_align(log
, start_block
);
1580 for (; j
< endcount
; j
++) {
1581 xlog_add_record(log
, offset
, cycle
, i
+j
,
1582 tail_cycle
, tail_block
);
1585 error
= xlog_bwrite(log
, start_block
, endcount
, buffer
);
1588 start_block
+= endcount
;
1598 * This routine is called to blow away any incomplete log writes out
1599 * in front of the log head. We do this so that we won't become confused
1600 * if we come up, write only a little bit more, and then crash again.
1601 * If we leave the partial log records out there, this situation could
1602 * cause us to think those partial writes are valid blocks since they
1603 * have the current cycle number. We get rid of them by overwriting them
1604 * with empty log records with the old cycle number rather than the
1607 * The tail lsn is passed in rather than taken from
1608 * the log so that we will not write over the unmount record after a
1609 * clean unmount in a 512 block log. Doing so would leave the log without
1610 * any valid log records in it until a new one was written. If we crashed
1611 * during that time we would not be able to recover.
1614 xlog_clear_stale_blocks(
1618 int tail_cycle
, head_cycle
;
1619 int tail_block
, head_block
;
1620 int tail_distance
, max_distance
;
1624 tail_cycle
= CYCLE_LSN(tail_lsn
);
1625 tail_block
= BLOCK_LSN(tail_lsn
);
1626 head_cycle
= log
->l_curr_cycle
;
1627 head_block
= log
->l_curr_block
;
1630 * Figure out the distance between the new head of the log
1631 * and the tail. We want to write over any blocks beyond the
1632 * head that we may have written just before the crash, but
1633 * we don't want to overwrite the tail of the log.
1635 if (head_cycle
== tail_cycle
) {
1637 * The tail is behind the head in the physical log,
1638 * so the distance from the head to the tail is the
1639 * distance from the head to the end of the log plus
1640 * the distance from the beginning of the log to the
1643 if (XFS_IS_CORRUPT(log
->l_mp
,
1644 head_block
< tail_block
||
1645 head_block
>= log
->l_logBBsize
))
1646 return -EFSCORRUPTED
;
1647 tail_distance
= tail_block
+ (log
->l_logBBsize
- head_block
);
1650 * The head is behind the tail in the physical log,
1651 * so the distance from the head to the tail is just
1652 * the tail block minus the head block.
1654 if (XFS_IS_CORRUPT(log
->l_mp
,
1655 head_block
>= tail_block
||
1656 head_cycle
!= tail_cycle
+ 1))
1657 return -EFSCORRUPTED
;
1658 tail_distance
= tail_block
- head_block
;
1662 * If the head is right up against the tail, we can't clear
1665 if (tail_distance
<= 0) {
1666 ASSERT(tail_distance
== 0);
1670 max_distance
= XLOG_TOTAL_REC_SHIFT(log
);
1672 * Take the smaller of the maximum amount of outstanding I/O
1673 * we could have and the distance to the tail to clear out.
1674 * We take the smaller so that we don't overwrite the tail and
1675 * we don't waste all day writing from the head to the tail
1678 max_distance
= min(max_distance
, tail_distance
);
1680 if ((head_block
+ max_distance
) <= log
->l_logBBsize
) {
1682 * We can stomp all the blocks we need to without
1683 * wrapping around the end of the log. Just do it
1684 * in a single write. Use the cycle number of the
1685 * current cycle minus one so that the log will look like:
1688 error
= xlog_write_log_records(log
, (head_cycle
- 1),
1689 head_block
, max_distance
, tail_cycle
,
1695 * We need to wrap around the end of the physical log in
1696 * order to clear all the blocks. Do it in two separate
1697 * I/Os. The first write should be from the head to the
1698 * end of the physical log, and it should use the current
1699 * cycle number minus one just like above.
1701 distance
= log
->l_logBBsize
- head_block
;
1702 error
= xlog_write_log_records(log
, (head_cycle
- 1),
1703 head_block
, distance
, tail_cycle
,
1710 * Now write the blocks at the start of the physical log.
1711 * This writes the remainder of the blocks we want to clear.
1712 * It uses the current cycle number since we're now on the
1713 * same cycle as the head so that we get:
1714 * n ... n ... | n - 1 ...
1715 * ^^^^^ blocks we're writing
1717 distance
= max_distance
- (log
->l_logBBsize
- head_block
);
1718 error
= xlog_write_log_records(log
, head_cycle
, 0, distance
,
1719 tail_cycle
, tail_block
);
1728 * Release the recovered intent item in the AIL that matches the given intent
1729 * type and intent id.
1732 xlog_recover_release_intent(
1734 unsigned short intent_type
,
1737 struct xfs_ail_cursor cur
;
1738 struct xfs_log_item
*lip
;
1739 struct xfs_ail
*ailp
= log
->l_ailp
;
1741 spin_lock(&ailp
->ail_lock
);
1742 for (lip
= xfs_trans_ail_cursor_first(ailp
, &cur
, 0); lip
!= NULL
;
1743 lip
= xfs_trans_ail_cursor_next(ailp
, &cur
)) {
1744 if (lip
->li_type
!= intent_type
)
1746 if (!lip
->li_ops
->iop_match(lip
, intent_id
))
1749 spin_unlock(&ailp
->ail_lock
);
1750 lip
->li_ops
->iop_release(lip
);
1751 spin_lock(&ailp
->ail_lock
);
1755 xfs_trans_ail_cursor_done(&cur
);
1756 spin_unlock(&ailp
->ail_lock
);
1761 struct xfs_mount
*mp
,
1763 struct xfs_inode
**ipp
)
1767 error
= xfs_iget(mp
, NULL
, ino
, 0, 0, ipp
);
1771 error
= xfs_qm_dqattach(*ipp
);
1777 if (VFS_I(*ipp
)->i_nlink
== 0)
1778 xfs_iflags_set(*ipp
, XFS_IRECOVERY
);
1783 /******************************************************************************
1785 * Log recover routines
1787 ******************************************************************************
1789 static const struct xlog_recover_item_ops
*xlog_recover_item_ops
[] = {
1791 &xlog_inode_item_ops
,
1792 &xlog_dquot_item_ops
,
1793 &xlog_quotaoff_item_ops
,
1794 &xlog_icreate_item_ops
,
1805 static const struct xlog_recover_item_ops
*
1807 struct xlog_recover_item
*item
)
1811 for (i
= 0; i
< ARRAY_SIZE(xlog_recover_item_ops
); i
++)
1812 if (ITEM_TYPE(item
) == xlog_recover_item_ops
[i
]->item_type
)
1813 return xlog_recover_item_ops
[i
];
1819 * Sort the log items in the transaction.
1821 * The ordering constraints are defined by the inode allocation and unlink
1822 * behaviour. The rules are:
1824 * 1. Every item is only logged once in a given transaction. Hence it
1825 * represents the last logged state of the item. Hence ordering is
1826 * dependent on the order in which operations need to be performed so
1827 * required initial conditions are always met.
1829 * 2. Cancelled buffers are recorded in pass 1 in a separate table and
1830 * there's nothing to replay from them so we can simply cull them
1831 * from the transaction. However, we can't do that until after we've
1832 * replayed all the other items because they may be dependent on the
1833 * cancelled buffer and replaying the cancelled buffer can remove it
1834 * form the cancelled buffer table. Hence they have tobe done last.
1836 * 3. Inode allocation buffers must be replayed before inode items that
1837 * read the buffer and replay changes into it. For filesystems using the
1838 * ICREATE transactions, this means XFS_LI_ICREATE objects need to get
1839 * treated the same as inode allocation buffers as they create and
1840 * initialise the buffers directly.
1842 * 4. Inode unlink buffers must be replayed after inode items are replayed.
1843 * This ensures that inodes are completely flushed to the inode buffer
1844 * in a "free" state before we remove the unlinked inode list pointer.
1846 * Hence the ordering needs to be inode allocation buffers first, inode items
1847 * second, inode unlink buffers third and cancelled buffers last.
1849 * But there's a problem with that - we can't tell an inode allocation buffer
1850 * apart from a regular buffer, so we can't separate them. We can, however,
1851 * tell an inode unlink buffer from the others, and so we can separate them out
1852 * from all the other buffers and move them to last.
1854 * Hence, 4 lists, in order from head to tail:
1855 * - buffer_list for all buffers except cancelled/inode unlink buffers
1856 * - item_list for all non-buffer items
1857 * - inode_buffer_list for inode unlink buffers
1858 * - cancel_list for the cancelled buffers
1860 * Note that we add objects to the tail of the lists so that first-to-last
1861 * ordering is preserved within the lists. Adding objects to the head of the
1862 * list means when we traverse from the head we walk them in last-to-first
1863 * order. For cancelled buffers and inode unlink buffers this doesn't matter,
1864 * but for all other items there may be specific ordering that we need to
1868 xlog_recover_reorder_trans(
1870 struct xlog_recover
*trans
,
1873 struct xlog_recover_item
*item
, *n
;
1875 LIST_HEAD(sort_list
);
1876 LIST_HEAD(cancel_list
);
1877 LIST_HEAD(buffer_list
);
1878 LIST_HEAD(inode_buffer_list
);
1879 LIST_HEAD(item_list
);
1881 list_splice_init(&trans
->r_itemq
, &sort_list
);
1882 list_for_each_entry_safe(item
, n
, &sort_list
, ri_list
) {
1883 enum xlog_recover_reorder fate
= XLOG_REORDER_ITEM_LIST
;
1885 item
->ri_ops
= xlog_find_item_ops(item
);
1886 if (!item
->ri_ops
) {
1888 "%s: unrecognized type of log operation (%d)",
1889 __func__
, ITEM_TYPE(item
));
1892 * return the remaining items back to the transaction
1893 * item list so they can be freed in caller.
1895 if (!list_empty(&sort_list
))
1896 list_splice_init(&sort_list
, &trans
->r_itemq
);
1897 error
= -EFSCORRUPTED
;
1901 if (item
->ri_ops
->reorder
)
1902 fate
= item
->ri_ops
->reorder(item
);
1905 case XLOG_REORDER_BUFFER_LIST
:
1906 list_move_tail(&item
->ri_list
, &buffer_list
);
1908 case XLOG_REORDER_CANCEL_LIST
:
1909 trace_xfs_log_recover_item_reorder_head(log
,
1911 list_move(&item
->ri_list
, &cancel_list
);
1913 case XLOG_REORDER_INODE_BUFFER_LIST
:
1914 list_move(&item
->ri_list
, &inode_buffer_list
);
1916 case XLOG_REORDER_ITEM_LIST
:
1917 trace_xfs_log_recover_item_reorder_tail(log
,
1919 list_move_tail(&item
->ri_list
, &item_list
);
1924 ASSERT(list_empty(&sort_list
));
1925 if (!list_empty(&buffer_list
))
1926 list_splice(&buffer_list
, &trans
->r_itemq
);
1927 if (!list_empty(&item_list
))
1928 list_splice_tail(&item_list
, &trans
->r_itemq
);
1929 if (!list_empty(&inode_buffer_list
))
1930 list_splice_tail(&inode_buffer_list
, &trans
->r_itemq
);
1931 if (!list_empty(&cancel_list
))
1932 list_splice_tail(&cancel_list
, &trans
->r_itemq
);
1941 const struct xfs_buf_ops
*ops
)
1943 if (!xlog_is_buffer_cancelled(log
, blkno
, len
))
1944 xfs_buf_readahead(log
->l_mp
->m_ddev_targp
, blkno
, len
, ops
);
1948 xlog_recover_items_pass2(
1950 struct xlog_recover
*trans
,
1951 struct list_head
*buffer_list
,
1952 struct list_head
*item_list
)
1954 struct xlog_recover_item
*item
;
1957 list_for_each_entry(item
, item_list
, ri_list
) {
1958 trace_xfs_log_recover_item_recover(log
, trans
, item
,
1959 XLOG_RECOVER_PASS2
);
1961 if (item
->ri_ops
->commit_pass2
)
1962 error
= item
->ri_ops
->commit_pass2(log
, buffer_list
,
1963 item
, trans
->r_lsn
);
1972 * Perform the transaction.
1974 * If the transaction modifies a buffer or inode, do it now. Otherwise,
1975 * EFIs and EFDs get queued up by adding entries into the AIL for them.
1978 xlog_recover_commit_trans(
1980 struct xlog_recover
*trans
,
1982 struct list_head
*buffer_list
)
1985 int items_queued
= 0;
1986 struct xlog_recover_item
*item
;
1987 struct xlog_recover_item
*next
;
1988 LIST_HEAD (ra_list
);
1989 LIST_HEAD (done_list
);
1991 #define XLOG_RECOVER_COMMIT_QUEUE_MAX 100
1993 hlist_del_init(&trans
->r_list
);
1995 error
= xlog_recover_reorder_trans(log
, trans
, pass
);
1999 list_for_each_entry_safe(item
, next
, &trans
->r_itemq
, ri_list
) {
2000 trace_xfs_log_recover_item_recover(log
, trans
, item
, pass
);
2003 case XLOG_RECOVER_PASS1
:
2004 if (item
->ri_ops
->commit_pass1
)
2005 error
= item
->ri_ops
->commit_pass1(log
, item
);
2007 case XLOG_RECOVER_PASS2
:
2008 if (item
->ri_ops
->ra_pass2
)
2009 item
->ri_ops
->ra_pass2(log
, item
);
2010 list_move_tail(&item
->ri_list
, &ra_list
);
2012 if (items_queued
>= XLOG_RECOVER_COMMIT_QUEUE_MAX
) {
2013 error
= xlog_recover_items_pass2(log
, trans
,
2014 buffer_list
, &ra_list
);
2015 list_splice_tail_init(&ra_list
, &done_list
);
2029 if (!list_empty(&ra_list
)) {
2031 error
= xlog_recover_items_pass2(log
, trans
,
2032 buffer_list
, &ra_list
);
2033 list_splice_tail_init(&ra_list
, &done_list
);
2036 if (!list_empty(&done_list
))
2037 list_splice_init(&done_list
, &trans
->r_itemq
);
2043 xlog_recover_add_item(
2044 struct list_head
*head
)
2046 struct xlog_recover_item
*item
;
2048 item
= kmem_zalloc(sizeof(struct xlog_recover_item
), 0);
2049 INIT_LIST_HEAD(&item
->ri_list
);
2050 list_add_tail(&item
->ri_list
, head
);
2054 xlog_recover_add_to_cont_trans(
2056 struct xlog_recover
*trans
,
2060 struct xlog_recover_item
*item
;
2061 char *ptr
, *old_ptr
;
2065 * If the transaction is empty, the header was split across this and the
2066 * previous record. Copy the rest of the header.
2068 if (list_empty(&trans
->r_itemq
)) {
2069 ASSERT(len
<= sizeof(struct xfs_trans_header
));
2070 if (len
> sizeof(struct xfs_trans_header
)) {
2071 xfs_warn(log
->l_mp
, "%s: bad header length", __func__
);
2072 return -EFSCORRUPTED
;
2075 xlog_recover_add_item(&trans
->r_itemq
);
2076 ptr
= (char *)&trans
->r_theader
+
2077 sizeof(struct xfs_trans_header
) - len
;
2078 memcpy(ptr
, dp
, len
);
2082 /* take the tail entry */
2083 item
= list_entry(trans
->r_itemq
.prev
, struct xlog_recover_item
,
2086 old_ptr
= item
->ri_buf
[item
->ri_cnt
-1].i_addr
;
2087 old_len
= item
->ri_buf
[item
->ri_cnt
-1].i_len
;
2089 ptr
= kvrealloc(old_ptr
, old_len
, len
+ old_len
, GFP_KERNEL
);
2092 memcpy(&ptr
[old_len
], dp
, len
);
2093 item
->ri_buf
[item
->ri_cnt
-1].i_len
+= len
;
2094 item
->ri_buf
[item
->ri_cnt
-1].i_addr
= ptr
;
2095 trace_xfs_log_recover_item_add_cont(log
, trans
, item
, 0);
2100 * The next region to add is the start of a new region. It could be
2101 * a whole region or it could be the first part of a new region. Because
2102 * of this, the assumption here is that the type and size fields of all
2103 * format structures fit into the first 32 bits of the structure.
2105 * This works because all regions must be 32 bit aligned. Therefore, we
2106 * either have both fields or we have neither field. In the case we have
2107 * neither field, the data part of the region is zero length. We only have
2108 * a log_op_header and can throw away the header since a new one will appear
2109 * later. If we have at least 4 bytes, then we can determine how many regions
2110 * will appear in the current log item.
2113 xlog_recover_add_to_trans(
2115 struct xlog_recover
*trans
,
2119 struct xfs_inode_log_format
*in_f
; /* any will do */
2120 struct xlog_recover_item
*item
;
2125 if (list_empty(&trans
->r_itemq
)) {
2126 /* we need to catch log corruptions here */
2127 if (*(uint
*)dp
!= XFS_TRANS_HEADER_MAGIC
) {
2128 xfs_warn(log
->l_mp
, "%s: bad header magic number",
2131 return -EFSCORRUPTED
;
2134 if (len
> sizeof(struct xfs_trans_header
)) {
2135 xfs_warn(log
->l_mp
, "%s: bad header length", __func__
);
2137 return -EFSCORRUPTED
;
2141 * The transaction header can be arbitrarily split across op
2142 * records. If we don't have the whole thing here, copy what we
2143 * do have and handle the rest in the next record.
2145 if (len
== sizeof(struct xfs_trans_header
))
2146 xlog_recover_add_item(&trans
->r_itemq
);
2147 memcpy(&trans
->r_theader
, dp
, len
);
2151 ptr
= kmem_alloc(len
, 0);
2152 memcpy(ptr
, dp
, len
);
2153 in_f
= (struct xfs_inode_log_format
*)ptr
;
2155 /* take the tail entry */
2156 item
= list_entry(trans
->r_itemq
.prev
, struct xlog_recover_item
,
2158 if (item
->ri_total
!= 0 &&
2159 item
->ri_total
== item
->ri_cnt
) {
2160 /* tail item is in use, get a new one */
2161 xlog_recover_add_item(&trans
->r_itemq
);
2162 item
= list_entry(trans
->r_itemq
.prev
,
2163 struct xlog_recover_item
, ri_list
);
2166 if (item
->ri_total
== 0) { /* first region to be added */
2167 if (in_f
->ilf_size
== 0 ||
2168 in_f
->ilf_size
> XLOG_MAX_REGIONS_IN_ITEM
) {
2170 "bad number of regions (%d) in inode log format",
2174 return -EFSCORRUPTED
;
2177 item
->ri_total
= in_f
->ilf_size
;
2179 kmem_zalloc(item
->ri_total
* sizeof(xfs_log_iovec_t
),
2183 if (item
->ri_total
<= item
->ri_cnt
) {
2185 "log item region count (%d) overflowed size (%d)",
2186 item
->ri_cnt
, item
->ri_total
);
2189 return -EFSCORRUPTED
;
2192 /* Description region is ri_buf[0] */
2193 item
->ri_buf
[item
->ri_cnt
].i_addr
= ptr
;
2194 item
->ri_buf
[item
->ri_cnt
].i_len
= len
;
2196 trace_xfs_log_recover_item_add(log
, trans
, item
, 0);
2201 * Free up any resources allocated by the transaction
2203 * Remember that EFIs, EFDs, and IUNLINKs are handled later.
2206 xlog_recover_free_trans(
2207 struct xlog_recover
*trans
)
2209 struct xlog_recover_item
*item
, *n
;
2212 hlist_del_init(&trans
->r_list
);
2214 list_for_each_entry_safe(item
, n
, &trans
->r_itemq
, ri_list
) {
2215 /* Free the regions in the item. */
2216 list_del(&item
->ri_list
);
2217 for (i
= 0; i
< item
->ri_cnt
; i
++)
2218 kmem_free(item
->ri_buf
[i
].i_addr
);
2219 /* Free the item itself */
2220 kmem_free(item
->ri_buf
);
2223 /* Free the transaction recover structure */
2228 * On error or completion, trans is freed.
2231 xlog_recovery_process_trans(
2233 struct xlog_recover
*trans
,
2238 struct list_head
*buffer_list
)
2241 bool freeit
= false;
2243 /* mask off ophdr transaction container flags */
2244 flags
&= ~XLOG_END_TRANS
;
2245 if (flags
& XLOG_WAS_CONT_TRANS
)
2246 flags
&= ~XLOG_CONTINUE_TRANS
;
2249 * Callees must not free the trans structure. We'll decide if we need to
2250 * free it or not based on the operation being done and it's result.
2253 /* expected flag values */
2255 case XLOG_CONTINUE_TRANS
:
2256 error
= xlog_recover_add_to_trans(log
, trans
, dp
, len
);
2258 case XLOG_WAS_CONT_TRANS
:
2259 error
= xlog_recover_add_to_cont_trans(log
, trans
, dp
, len
);
2261 case XLOG_COMMIT_TRANS
:
2262 error
= xlog_recover_commit_trans(log
, trans
, pass
,
2264 /* success or fail, we are now done with this transaction. */
2268 /* unexpected flag values */
2269 case XLOG_UNMOUNT_TRANS
:
2270 /* just skip trans */
2271 xfs_warn(log
->l_mp
, "%s: Unmount LR", __func__
);
2274 case XLOG_START_TRANS
:
2276 xfs_warn(log
->l_mp
, "%s: bad flag 0x%x", __func__
, flags
);
2278 error
= -EFSCORRUPTED
;
2281 if (error
|| freeit
)
2282 xlog_recover_free_trans(trans
);
2287 * Lookup the transaction recovery structure associated with the ID in the
2288 * current ophdr. If the transaction doesn't exist and the start flag is set in
2289 * the ophdr, then allocate a new transaction for future ID matches to find.
2290 * Either way, return what we found during the lookup - an existing transaction
2293 STATIC
struct xlog_recover
*
2294 xlog_recover_ophdr_to_trans(
2295 struct hlist_head rhash
[],
2296 struct xlog_rec_header
*rhead
,
2297 struct xlog_op_header
*ohead
)
2299 struct xlog_recover
*trans
;
2301 struct hlist_head
*rhp
;
2303 tid
= be32_to_cpu(ohead
->oh_tid
);
2304 rhp
= &rhash
[XLOG_RHASH(tid
)];
2305 hlist_for_each_entry(trans
, rhp
, r_list
) {
2306 if (trans
->r_log_tid
== tid
)
2311 * skip over non-start transaction headers - we could be
2312 * processing slack space before the next transaction starts
2314 if (!(ohead
->oh_flags
& XLOG_START_TRANS
))
2317 ASSERT(be32_to_cpu(ohead
->oh_len
) == 0);
2320 * This is a new transaction so allocate a new recovery container to
2321 * hold the recovery ops that will follow.
2323 trans
= kmem_zalloc(sizeof(struct xlog_recover
), 0);
2324 trans
->r_log_tid
= tid
;
2325 trans
->r_lsn
= be64_to_cpu(rhead
->h_lsn
);
2326 INIT_LIST_HEAD(&trans
->r_itemq
);
2327 INIT_HLIST_NODE(&trans
->r_list
);
2328 hlist_add_head(&trans
->r_list
, rhp
);
2331 * Nothing more to do for this ophdr. Items to be added to this new
2332 * transaction will be in subsequent ophdr containers.
2338 xlog_recover_process_ophdr(
2340 struct hlist_head rhash
[],
2341 struct xlog_rec_header
*rhead
,
2342 struct xlog_op_header
*ohead
,
2346 struct list_head
*buffer_list
)
2348 struct xlog_recover
*trans
;
2352 /* Do we understand who wrote this op? */
2353 if (ohead
->oh_clientid
!= XFS_TRANSACTION
&&
2354 ohead
->oh_clientid
!= XFS_LOG
) {
2355 xfs_warn(log
->l_mp
, "%s: bad clientid 0x%x",
2356 __func__
, ohead
->oh_clientid
);
2358 return -EFSCORRUPTED
;
2362 * Check the ophdr contains all the data it is supposed to contain.
2364 len
= be32_to_cpu(ohead
->oh_len
);
2365 if (dp
+ len
> end
) {
2366 xfs_warn(log
->l_mp
, "%s: bad length 0x%x", __func__
, len
);
2368 return -EFSCORRUPTED
;
2371 trans
= xlog_recover_ophdr_to_trans(rhash
, rhead
, ohead
);
2373 /* nothing to do, so skip over this ophdr */
2378 * The recovered buffer queue is drained only once we know that all
2379 * recovery items for the current LSN have been processed. This is
2382 * - Buffer write submission updates the metadata LSN of the buffer.
2383 * - Log recovery skips items with a metadata LSN >= the current LSN of
2384 * the recovery item.
2385 * - Separate recovery items against the same metadata buffer can share
2386 * a current LSN. I.e., consider that the LSN of a recovery item is
2387 * defined as the starting LSN of the first record in which its
2388 * transaction appears, that a record can hold multiple transactions,
2389 * and/or that a transaction can span multiple records.
2391 * In other words, we are allowed to submit a buffer from log recovery
2392 * once per current LSN. Otherwise, we may incorrectly skip recovery
2393 * items and cause corruption.
2395 * We don't know up front whether buffers are updated multiple times per
2396 * LSN. Therefore, track the current LSN of each commit log record as it
2397 * is processed and drain the queue when it changes. Use commit records
2398 * because they are ordered correctly by the logging code.
2400 if (log
->l_recovery_lsn
!= trans
->r_lsn
&&
2401 ohead
->oh_flags
& XLOG_COMMIT_TRANS
) {
2402 error
= xfs_buf_delwri_submit(buffer_list
);
2405 log
->l_recovery_lsn
= trans
->r_lsn
;
2408 return xlog_recovery_process_trans(log
, trans
, dp
, len
,
2409 ohead
->oh_flags
, pass
, buffer_list
);
2413 * There are two valid states of the r_state field. 0 indicates that the
2414 * transaction structure is in a normal state. We have either seen the
2415 * start of the transaction or the last operation we added was not a partial
2416 * operation. If the last operation we added to the transaction was a
2417 * partial operation, we need to mark r_state with XLOG_WAS_CONT_TRANS.
2419 * NOTE: skip LRs with 0 data length.
2422 xlog_recover_process_data(
2424 struct hlist_head rhash
[],
2425 struct xlog_rec_header
*rhead
,
2428 struct list_head
*buffer_list
)
2430 struct xlog_op_header
*ohead
;
2435 end
= dp
+ be32_to_cpu(rhead
->h_len
);
2436 num_logops
= be32_to_cpu(rhead
->h_num_logops
);
2438 /* check the log format matches our own - else we can't recover */
2439 if (xlog_header_check_recover(log
->l_mp
, rhead
))
2442 trace_xfs_log_recover_record(log
, rhead
, pass
);
2443 while ((dp
< end
) && num_logops
) {
2445 ohead
= (struct xlog_op_header
*)dp
;
2446 dp
+= sizeof(*ohead
);
2449 /* errors will abort recovery */
2450 error
= xlog_recover_process_ophdr(log
, rhash
, rhead
, ohead
,
2451 dp
, end
, pass
, buffer_list
);
2455 dp
+= be32_to_cpu(ohead
->oh_len
);
2461 /* Take all the collected deferred ops and finish them in order. */
2463 xlog_finish_defer_ops(
2464 struct xfs_mount
*mp
,
2465 struct list_head
*capture_list
)
2467 struct xfs_defer_capture
*dfc
, *next
;
2468 struct xfs_trans
*tp
;
2469 struct xfs_inode
*ip
;
2472 list_for_each_entry_safe(dfc
, next
, capture_list
, dfc_list
) {
2473 struct xfs_trans_res resv
;
2476 * Create a new transaction reservation from the captured
2477 * information. Set logcount to 1 to force the new transaction
2478 * to regrant every roll so that we can make forward progress
2479 * in recovery no matter how full the log might be.
2481 resv
.tr_logres
= dfc
->dfc_logres
;
2482 resv
.tr_logcount
= 1;
2483 resv
.tr_logflags
= XFS_TRANS_PERM_LOG_RES
;
2485 error
= xfs_trans_alloc(mp
, &resv
, dfc
->dfc_blkres
,
2486 dfc
->dfc_rtxres
, XFS_TRANS_RESERVE
, &tp
);
2488 xfs_force_shutdown(mp
, SHUTDOWN_LOG_IO_ERROR
);
2493 * Transfer to this new transaction all the dfops we captured
2494 * from recovering a single intent item.
2496 list_del_init(&dfc
->dfc_list
);
2497 xfs_defer_ops_continue(dfc
, tp
, &ip
);
2499 error
= xfs_trans_commit(tp
);
2501 xfs_iunlock(ip
, XFS_ILOCK_EXCL
);
2508 ASSERT(list_empty(capture_list
));
2512 /* Release all the captured defer ops and capture structures in this list. */
2514 xlog_abort_defer_ops(
2515 struct xfs_mount
*mp
,
2516 struct list_head
*capture_list
)
2518 struct xfs_defer_capture
*dfc
;
2519 struct xfs_defer_capture
*next
;
2521 list_for_each_entry_safe(dfc
, next
, capture_list
, dfc_list
) {
2522 list_del_init(&dfc
->dfc_list
);
2523 xfs_defer_ops_release(mp
, dfc
);
2527 * When this is called, all of the log intent items which did not have
2528 * corresponding log done items should be in the AIL. What we do now
2529 * is update the data structures associated with each one.
2531 * Since we process the log intent items in normal transactions, they
2532 * will be removed at some point after the commit. This prevents us
2533 * from just walking down the list processing each one. We'll use a
2534 * flag in the intent item to skip those that we've already processed
2535 * and use the AIL iteration mechanism's generation count to try to
2536 * speed this up at least a bit.
2538 * When we start, we know that the intents are the only things in the
2539 * AIL. As we process them, however, other items are added to the
2543 xlog_recover_process_intents(
2546 LIST_HEAD(capture_list
);
2547 struct xfs_ail_cursor cur
;
2548 struct xfs_log_item
*lip
;
2549 struct xfs_ail
*ailp
;
2551 #if defined(DEBUG) || defined(XFS_WARN)
2556 spin_lock(&ailp
->ail_lock
);
2557 #if defined(DEBUG) || defined(XFS_WARN)
2558 last_lsn
= xlog_assign_lsn(log
->l_curr_cycle
, log
->l_curr_block
);
2560 for (lip
= xfs_trans_ail_cursor_first(ailp
, &cur
, 0);
2562 lip
= xfs_trans_ail_cursor_next(ailp
, &cur
)) {
2564 * We're done when we see something other than an intent.
2565 * There should be no intents left in the AIL now.
2567 if (!xlog_item_is_intent(lip
)) {
2569 for (; lip
; lip
= xfs_trans_ail_cursor_next(ailp
, &cur
))
2570 ASSERT(!xlog_item_is_intent(lip
));
2576 * We should never see a redo item with a LSN higher than
2577 * the last transaction we found in the log at the start
2580 ASSERT(XFS_LSN_CMP(last_lsn
, lip
->li_lsn
) >= 0);
2583 * NOTE: If your intent processing routine can create more
2584 * deferred ops, you /must/ attach them to the capture list in
2585 * the recover routine or else those subsequent intents will be
2586 * replayed in the wrong order!
2588 spin_unlock(&ailp
->ail_lock
);
2589 error
= lip
->li_ops
->iop_recover(lip
, &capture_list
);
2590 spin_lock(&ailp
->ail_lock
);
2592 trace_xlog_intent_recovery_failed(log
->l_mp
, error
,
2593 lip
->li_ops
->iop_recover
);
2598 xfs_trans_ail_cursor_done(&cur
);
2599 spin_unlock(&ailp
->ail_lock
);
2603 error
= xlog_finish_defer_ops(log
->l_mp
, &capture_list
);
2609 xlog_abort_defer_ops(log
->l_mp
, &capture_list
);
2614 * A cancel occurs when the mount has failed and we're bailing out.
2615 * Release all pending log intent items so they don't pin the AIL.
2618 xlog_recover_cancel_intents(
2621 struct xfs_log_item
*lip
;
2622 struct xfs_ail_cursor cur
;
2623 struct xfs_ail
*ailp
;
2626 spin_lock(&ailp
->ail_lock
);
2627 lip
= xfs_trans_ail_cursor_first(ailp
, &cur
, 0);
2628 while (lip
!= NULL
) {
2630 * We're done when we see something other than an intent.
2631 * There should be no intents left in the AIL now.
2633 if (!xlog_item_is_intent(lip
)) {
2635 for (; lip
; lip
= xfs_trans_ail_cursor_next(ailp
, &cur
))
2636 ASSERT(!xlog_item_is_intent(lip
));
2641 spin_unlock(&ailp
->ail_lock
);
2642 lip
->li_ops
->iop_release(lip
);
2643 spin_lock(&ailp
->ail_lock
);
2644 lip
= xfs_trans_ail_cursor_next(ailp
, &cur
);
2647 xfs_trans_ail_cursor_done(&cur
);
2648 spin_unlock(&ailp
->ail_lock
);
2652 * This routine performs a transaction to null out a bad inode pointer
2653 * in an agi unlinked inode hash bucket.
2656 xlog_recover_clear_agi_bucket(
2658 xfs_agnumber_t agno
,
2663 struct xfs_buf
*agibp
;
2667 error
= xfs_trans_alloc(mp
, &M_RES(mp
)->tr_clearagi
, 0, 0, 0, &tp
);
2671 error
= xfs_read_agi(mp
, tp
, agno
, &agibp
);
2675 agi
= agibp
->b_addr
;
2676 agi
->agi_unlinked
[bucket
] = cpu_to_be32(NULLAGINO
);
2677 offset
= offsetof(xfs_agi_t
, agi_unlinked
) +
2678 (sizeof(xfs_agino_t
) * bucket
);
2679 xfs_trans_log_buf(tp
, agibp
, offset
,
2680 (offset
+ sizeof(xfs_agino_t
) - 1));
2682 error
= xfs_trans_commit(tp
);
2688 xfs_trans_cancel(tp
);
2690 xfs_warn(mp
, "%s: failed to clear agi %d. Continuing.", __func__
, agno
);
2695 xlog_recover_process_one_iunlink(
2696 struct xfs_mount
*mp
,
2697 xfs_agnumber_t agno
,
2701 struct xfs_buf
*ibp
;
2702 struct xfs_dinode
*dip
;
2703 struct xfs_inode
*ip
;
2707 ino
= XFS_AGINO_TO_INO(mp
, agno
, agino
);
2708 error
= xfs_iget(mp
, NULL
, ino
, 0, 0, &ip
);
2713 * Get the on disk inode to find the next inode in the bucket.
2715 error
= xfs_imap_to_bp(mp
, NULL
, &ip
->i_imap
, &ibp
);
2718 dip
= xfs_buf_offset(ibp
, ip
->i_imap
.im_boffset
);
2720 xfs_iflags_clear(ip
, XFS_IRECOVERY
);
2721 ASSERT(VFS_I(ip
)->i_nlink
== 0);
2722 ASSERT(VFS_I(ip
)->i_mode
!= 0);
2724 /* setup for the next pass */
2725 agino
= be32_to_cpu(dip
->di_next_unlinked
);
2735 * We can't read in the inode this bucket points to, or this inode
2736 * is messed up. Just ditch this bucket of inodes. We will lose
2737 * some inodes and space, but at least we won't hang.
2739 * Call xlog_recover_clear_agi_bucket() to perform a transaction to
2740 * clear the inode pointer in the bucket.
2742 xlog_recover_clear_agi_bucket(mp
, agno
, bucket
);
2747 * Recover AGI unlinked lists
2749 * This is called during recovery to process any inodes which we unlinked but
2750 * not freed when the system crashed. These inodes will be on the lists in the
2751 * AGI blocks. What we do here is scan all the AGIs and fully truncate and free
2752 * any inodes found on the lists. Each inode is removed from the lists when it
2753 * has been fully truncated and is freed. The freeing of the inode and its
2754 * removal from the list must be atomic.
2756 * If everything we touch in the agi processing loop is already in memory, this
2757 * loop can hold the cpu for a long time. It runs without lock contention,
2758 * memory allocation contention, the need wait for IO, etc, and so will run
2759 * until we either run out of inodes to process, run low on memory or we run out
2762 * This behaviour is bad for latency on single CPU and non-preemptible kernels,
2763 * and can prevent other filesystem work (such as CIL pushes) from running. This
2764 * can lead to deadlocks if the recovery process runs out of log reservation
2765 * space. Hence we need to yield the CPU when there is other kernel work
2766 * scheduled on this CPU to ensure other scheduled work can run without undue
2770 xlog_recover_process_iunlinks(
2773 struct xfs_mount
*mp
= log
->l_mp
;
2774 struct xfs_perag
*pag
;
2775 xfs_agnumber_t agno
;
2776 struct xfs_agi
*agi
;
2777 struct xfs_buf
*agibp
;
2782 for_each_perag(mp
, agno
, pag
) {
2783 error
= xfs_read_agi(mp
, NULL
, pag
->pag_agno
, &agibp
);
2786 * AGI is b0rked. Don't process it.
2788 * We should probably mark the filesystem as corrupt
2789 * after we've recovered all the ag's we can....
2794 * Unlock the buffer so that it can be acquired in the normal
2795 * course of the transaction to truncate and free each inode.
2796 * Because we are not racing with anyone else here for the AGI
2797 * buffer, we don't even need to hold it locked to read the
2798 * initial unlinked bucket entries out of the buffer. We keep
2799 * buffer reference though, so that it stays pinned in memory
2800 * while we need the buffer.
2802 agi
= agibp
->b_addr
;
2803 xfs_buf_unlock(agibp
);
2805 for (bucket
= 0; bucket
< XFS_AGI_UNLINKED_BUCKETS
; bucket
++) {
2806 agino
= be32_to_cpu(agi
->agi_unlinked
[bucket
]);
2807 while (agino
!= NULLAGINO
) {
2808 agino
= xlog_recover_process_one_iunlink(mp
,
2809 pag
->pag_agno
, agino
, bucket
);
2813 xfs_buf_rele(agibp
);
2817 * Flush the pending unlinked inodes to ensure that the inactivations
2818 * are fully completed on disk and the incore inodes can be reclaimed
2819 * before we signal that recovery is complete.
2821 xfs_inodegc_flush(mp
);
2826 struct xlog_rec_header
*rhead
,
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
];
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
];
2850 * CRC check, unpack and process a log record.
2853 xlog_recover_process(
2855 struct hlist_head rhash
[],
2856 struct xlog_rec_header
*rhead
,
2859 struct list_head
*buffer_list
)
2861 __le32 old_crc
= rhead
->h_crc
;
2864 crc
= xlog_cksum(log
, rhead
, dp
, be32_to_cpu(rhead
->h_len
));
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.
2873 if (pass
== XLOG_RECOVER_CRCPASS
) {
2874 if (old_crc
&& crc
!= old_crc
)
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.
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
),
2891 xfs_hex_dump(dp
, 32);
2895 * If the filesystem is CRC enabled, this mismatch becomes a
2896 * fatal log corruption failure.
2898 if (xfs_has_crc(log
->l_mp
)) {
2899 XFS_ERROR_REPORT(__func__
, XFS_ERRLEVEL_LOW
, log
->l_mp
);
2900 return -EFSCORRUPTED
;
2904 xlog_unpack_data(rhead
, dp
, log
);
2906 return xlog_recover_process_data(log
, rhash
, rhead
, dp
, pass
,
2911 xlog_valid_rec_header(
2913 struct xlog_rec_header
*rhead
,
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
;
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.
2935 hlen
= be32_to_cpu(rhead
->h_len
);
2936 if (XFS_IS_CORRUPT(log
->l_mp
, hlen
<= 0 || hlen
> bufsize
))
2937 return -EFSCORRUPTED
;
2939 if (XFS_IS_CORRUPT(log
->l_mp
,
2940 blkno
> log
->l_logBBsize
|| blkno
> INT_MAX
))
2941 return -EFSCORRUPTED
;
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
2954 xlog_do_recovery_pass(
2956 xfs_daddr_t head_blk
,
2957 xfs_daddr_t tail_blk
,
2959 xfs_daddr_t
*first_bad
) /* out: first bad log rec */
2961 xlog_rec_header_t
*rhead
;
2962 xfs_daddr_t blk_no
, rblk_no
;
2963 xfs_daddr_t rhead_blk
;
2966 int error
= 0, h_size
, h_len
;
2968 int bblks
, split_bblks
;
2969 int hblks
, split_hblks
, wrapped_hblks
;
2971 struct hlist_head rhash
[XLOG_RHASH_SIZE
];
2972 LIST_HEAD (buffer_list
);
2974 ASSERT(head_blk
!= tail_blk
);
2975 blk_no
= rhead_blk
= tail_blk
;
2977 for (i
= 0; i
< XLOG_RHASH_SIZE
; i
++)
2978 INIT_HLIST_HEAD(&rhash
[i
]);
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.
2984 if (xfs_has_logv2(log
->l_mp
)) {
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.
2990 hbp
= xlog_alloc_buffer(log
, 1);
2994 error
= xlog_bread(log
, tail_blk
, 1, hbp
, &offset
);
2998 rhead
= (xlog_rec_header_t
*)offset
;
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
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.
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)) {
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
;
3021 error
= xlog_valid_rec_header(log
, rhead
, tail_blk
, h_size
);
3025 hblks
= xlog_logrec_hblks(log
, rhead
);
3028 hbp
= xlog_alloc_buffer(log
, hblks
);
3031 ASSERT(log
->l_sectBBsize
== 1);
3033 hbp
= xlog_alloc_buffer(log
, 1);
3034 h_size
= XLOG_BIG_RECORD_BSIZE
;
3039 dbp
= xlog_alloc_buffer(log
, BTOBB(h_size
));
3045 memset(rhash
, 0, sizeof(rhash
));
3046 if (tail_blk
> head_blk
) {
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.
3052 while (blk_no
< log
->l_logBBsize
) {
3054 * Check for header wrapping around physical end-of-log
3059 if (blk_no
+ hblks
<= log
->l_logBBsize
) {
3060 /* Read header in one read */
3061 error
= xlog_bread(log
, blk_no
, hblks
, hbp
,
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
,
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
3087 * - we read the log end (LR header start)
3088 * _first_, then the log start (LR header end)
3089 * - order is important.
3091 wrapped_hblks
= hblks
- split_hblks
;
3092 error
= xlog_bread_noalign(log
, 0,
3094 offset
+ BBTOB(split_hblks
));
3098 rhead
= (xlog_rec_header_t
*)offset
;
3099 error
= xlog_valid_rec_header(log
, rhead
,
3100 split_hblks
? blk_no
: 0, h_size
);
3104 bblks
= (int)BTOBB(be32_to_cpu(rhead
->h_len
));
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
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
,
3122 /* This log record is split across the
3123 * physical end of log */
3126 if (blk_no
!= log
->l_logBBsize
) {
3127 /* some data is before the physical
3129 ASSERT(!wrapped_hblks
);
3130 ASSERT(blk_no
<= INT_MAX
);
3132 log
->l_logBBsize
- (int)blk_no
;
3133 ASSERT(split_bblks
> 0);
3134 error
= xlog_bread(log
, blk_no
,
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
3149 * - we read the log end (LR header start)
3150 * _first_, then the log start (LR header end)
3151 * - order is important.
3153 error
= xlog_bread_noalign(log
, 0,
3154 bblks
- split_bblks
,
3155 offset
+ BBTOB(split_bblks
));
3160 error
= xlog_recover_process(log
, rhash
, rhead
, offset
,
3161 pass
, &buffer_list
);
3169 ASSERT(blk_no
>= log
->l_logBBsize
);
3170 blk_no
-= log
->l_logBBsize
;
3174 /* read first part of physical log */
3175 while (blk_no
< head_blk
) {
3176 error
= xlog_bread(log
, blk_no
, hblks
, hbp
, &offset
);
3180 rhead
= (xlog_rec_header_t
*)offset
;
3181 error
= xlog_valid_rec_header(log
, rhead
, blk_no
, h_size
);
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
,
3192 error
= xlog_recover_process(log
, rhash
, rhead
, offset
, pass
,
3197 blk_no
+= bblks
+ hblks
;
3207 * Submit buffers that have been added from the last record processed,
3208 * regardless of error status.
3210 if (!list_empty(&buffer_list
))
3211 error2
= xfs_buf_delwri_submit(&buffer_list
);
3213 if (error
&& first_bad
)
3214 *first_bad
= rhead_blk
;
3217 * Transactions are freed at commit time but transactions without commit
3218 * records on disk are never committed. Free any that may be left in the
3221 for (i
= 0; i
< XLOG_RHASH_SIZE
; i
++) {
3222 struct hlist_node
*tmp
;
3223 struct xlog_recover
*trans
;
3225 hlist_for_each_entry_safe(trans
, tmp
, &rhash
[i
], r_list
)
3226 xlog_recover_free_trans(trans
);
3229 return error
? error
: error2
;
3233 * Do the recovery of the log. We actually do this in two phases.
3234 * The two passes are necessary in order to implement the function
3235 * of cancelling a record written into the log. The first pass
3236 * determines those things which have been cancelled, and the
3237 * second pass replays log items normally except for those which
3238 * have been cancelled. The handling of the replay and cancellations
3239 * takes place in the log item type specific routines.
3241 * The table of items which have cancel records in the log is allocated
3242 * and freed at this level, since only here do we know when all of
3243 * the log recovery has been completed.
3246 xlog_do_log_recovery(
3248 xfs_daddr_t head_blk
,
3249 xfs_daddr_t tail_blk
)
3253 ASSERT(head_blk
!= tail_blk
);
3256 * First do a pass to find all of the cancelled buf log items.
3257 * Store them in the buf_cancel_table for use in the second pass.
3259 log
->l_buf_cancel_table
= kmem_zalloc(XLOG_BC_TABLE_SIZE
*
3260 sizeof(struct list_head
),
3262 for (i
= 0; i
< XLOG_BC_TABLE_SIZE
; i
++)
3263 INIT_LIST_HEAD(&log
->l_buf_cancel_table
[i
]);
3265 error
= xlog_do_recovery_pass(log
, head_blk
, tail_blk
,
3266 XLOG_RECOVER_PASS1
, NULL
);
3268 kmem_free(log
->l_buf_cancel_table
);
3269 log
->l_buf_cancel_table
= NULL
;
3273 * Then do a second pass to actually recover the items in the log.
3274 * When it is complete free the table of buf cancel items.
3276 error
= xlog_do_recovery_pass(log
, head_blk
, tail_blk
,
3277 XLOG_RECOVER_PASS2
, NULL
);
3282 for (i
= 0; i
< XLOG_BC_TABLE_SIZE
; i
++)
3283 ASSERT(list_empty(&log
->l_buf_cancel_table
[i
]));
3287 kmem_free(log
->l_buf_cancel_table
);
3288 log
->l_buf_cancel_table
= NULL
;
3294 * Do the actual recovery
3299 xfs_daddr_t head_blk
,
3300 xfs_daddr_t tail_blk
)
3302 struct xfs_mount
*mp
= log
->l_mp
;
3303 struct xfs_buf
*bp
= mp
->m_sb_bp
;
3304 struct xfs_sb
*sbp
= &mp
->m_sb
;
3307 trace_xfs_log_recover(log
, head_blk
, tail_blk
);
3310 * First replay the images in the log.
3312 error
= xlog_do_log_recovery(log
, head_blk
, tail_blk
);
3316 if (xlog_is_shutdown(log
))
3320 * We now update the tail_lsn since much of the recovery has completed
3321 * and there may be space available to use. If there were no extent
3322 * or iunlinks, we can free up the entire log and set the tail_lsn to
3323 * be the last_sync_lsn. This was set in xlog_find_tail to be the
3324 * lsn of the last known good LR on disk. If there are extent frees
3325 * or iunlinks they will have some entries in the AIL; so we look at
3326 * the AIL to determine how to set the tail_lsn.
3328 xlog_assign_tail_lsn(mp
);
3331 * Now that we've finished replaying all buffer and inode updates,
3332 * re-read the superblock and reverify it.
3336 error
= _xfs_buf_read(bp
, XBF_READ
);
3338 if (!xlog_is_shutdown(log
)) {
3339 xfs_buf_ioerror_alert(bp
, __this_address
);
3346 /* Convert superblock from on-disk format */
3347 xfs_sb_from_disk(sbp
, bp
->b_addr
);
3350 /* re-initialise in-core superblock and geometry structures */
3351 mp
->m_features
|= xfs_sb_version_to_features(sbp
);
3352 xfs_reinit_percpu_counters(mp
);
3353 error
= xfs_initialize_perag(mp
, sbp
->sb_agcount
, &mp
->m_maxagi
);
3355 xfs_warn(mp
, "Failed post-recovery per-ag init: %d", error
);
3358 mp
->m_alloc_set_aside
= xfs_alloc_set_aside(mp
);
3360 xlog_recover_check_summary(log
);
3362 /* Normal transactions can now occur */
3363 clear_bit(XLOG_ACTIVE_RECOVERY
, &log
->l_opstate
);
3368 * Perform recovery and re-initialize some log variables in xlog_find_tail.
3370 * Return error or zero.
3376 xfs_daddr_t head_blk
, tail_blk
;
3379 /* find the tail of the log */
3380 error
= xlog_find_tail(log
, &head_blk
, &tail_blk
);
3385 * The superblock was read before the log was available and thus the LSN
3386 * could not be verified. Check the superblock LSN against the current
3387 * LSN now that it's known.
3389 if (xfs_has_crc(log
->l_mp
) &&
3390 !xfs_log_check_lsn(log
->l_mp
, log
->l_mp
->m_sb
.sb_lsn
))
3393 if (tail_blk
!= head_blk
) {
3394 /* There used to be a comment here:
3396 * disallow recovery on read-only mounts. note -- mount
3397 * checks for ENOSPC and turns it into an intelligent
3399 * ...but this is no longer true. Now, unless you specify
3400 * NORECOVERY (in which case this function would never be
3401 * called), we just go ahead and recover. We do this all
3402 * under the vfs layer, so we can get away with it unless
3403 * the device itself is read-only, in which case we fail.
3405 if ((error
= xfs_dev_is_read_only(log
->l_mp
, "recovery"))) {
3410 * Version 5 superblock log feature mask validation. We know the
3411 * log is dirty so check if there are any unknown log features
3412 * in what we need to recover. If there are unknown features
3413 * (e.g. unsupported transactions, then simply reject the
3414 * attempt at recovery before touching anything.
3416 if (xfs_sb_is_v5(&log
->l_mp
->m_sb
) &&
3417 xfs_sb_has_incompat_log_feature(&log
->l_mp
->m_sb
,
3418 XFS_SB_FEAT_INCOMPAT_LOG_UNKNOWN
)) {
3420 "Superblock has unknown incompatible log features (0x%x) enabled.",
3421 (log
->l_mp
->m_sb
.sb_features_log_incompat
&
3422 XFS_SB_FEAT_INCOMPAT_LOG_UNKNOWN
));
3424 "The log can not be fully and/or safely recovered by this kernel.");
3426 "Please recover the log on a kernel that supports the unknown features.");
3431 * Delay log recovery if the debug hook is set. This is debug
3432 * instrumentation to coordinate simulation of I/O failures with
3435 if (xfs_globals
.log_recovery_delay
) {
3436 xfs_notice(log
->l_mp
,
3437 "Delaying log recovery for %d seconds.",
3438 xfs_globals
.log_recovery_delay
);
3439 msleep(xfs_globals
.log_recovery_delay
* 1000);
3442 xfs_notice(log
->l_mp
, "Starting recovery (logdev: %s)",
3443 log
->l_mp
->m_logname
? log
->l_mp
->m_logname
3446 error
= xlog_do_recover(log
, head_blk
, tail_blk
);
3447 set_bit(XLOG_RECOVERY_NEEDED
, &log
->l_opstate
);
3453 * In the first part of recovery we replay inodes and buffers and build up the
3454 * list of intents which need to be processed. Here we process the intents and
3455 * clean up the on disk unlinked inode lists. This is separated from the first
3456 * part of recovery so that the root and real-time bitmap inodes can be read in
3457 * from disk in between the two stages. This is necessary so that we can free
3458 * space in the real-time portion of the file system.
3461 xlog_recover_finish(
3466 error
= xlog_recover_process_intents(log
);
3469 * Cancel all the unprocessed intent items now so that we don't
3470 * leave them pinned in the AIL. This can cause the AIL to
3471 * livelock on the pinned item if anyone tries to push the AIL
3472 * (inode reclaim does this) before we get around to
3473 * xfs_log_mount_cancel.
3475 xlog_recover_cancel_intents(log
);
3476 xfs_alert(log
->l_mp
, "Failed to recover intents");
3477 xfs_force_shutdown(log
->l_mp
, SHUTDOWN_LOG_IO_ERROR
);
3482 * Sync the log to get all the intents out of the AIL. This isn't
3483 * absolutely necessary, but it helps in case the unlink transactions
3484 * would have problems pushing the intents out of the way.
3486 xfs_log_force(log
->l_mp
, XFS_LOG_SYNC
);
3489 * Now that we've recovered the log and all the intents, we can clear
3490 * the log incompat feature bits in the superblock because there's no
3491 * longer anything to protect. We rely on the AIL push to write out the
3492 * updated superblock after everything else.
3494 if (xfs_clear_incompat_log_features(log
->l_mp
)) {
3495 error
= xfs_sync_sb(log
->l_mp
, false);
3497 xfs_alert(log
->l_mp
,
3498 "Failed to clear log incompat features on recovery");
3503 xlog_recover_process_iunlinks(log
);
3504 xlog_recover_check_summary(log
);
3509 xlog_recover_cancel(
3512 if (xlog_recovery_needed(log
))
3513 xlog_recover_cancel_intents(log
);
3518 * Read all of the agf and agi counters and check that they
3519 * are consistent with the superblock counters.
3522 xlog_recover_check_summary(
3525 struct xfs_mount
*mp
= log
->l_mp
;
3526 struct xfs_perag
*pag
;
3527 struct xfs_buf
*agfbp
;
3528 struct xfs_buf
*agibp
;
3529 xfs_agnumber_t agno
;
3540 for_each_perag(mp
, agno
, pag
) {
3541 error
= xfs_read_agf(mp
, NULL
, pag
->pag_agno
, 0, &agfbp
);
3543 xfs_alert(mp
, "%s agf read failed agno %d error %d",
3544 __func__
, pag
->pag_agno
, error
);
3546 struct xfs_agf
*agfp
= agfbp
->b_addr
;
3548 freeblks
+= be32_to_cpu(agfp
->agf_freeblks
) +
3549 be32_to_cpu(agfp
->agf_flcount
);
3550 xfs_buf_relse(agfbp
);
3553 error
= xfs_read_agi(mp
, NULL
, pag
->pag_agno
, &agibp
);
3555 xfs_alert(mp
, "%s agi read failed agno %d error %d",
3556 __func__
, pag
->pag_agno
, error
);
3558 struct xfs_agi
*agi
= agibp
->b_addr
;
3560 itotal
+= be32_to_cpu(agi
->agi_count
);
3561 ifree
+= be32_to_cpu(agi
->agi_freecount
);
3562 xfs_buf_relse(agibp
);