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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_inum.h"
26#include "xfs_sb.h"
27#include "xfs_ag.h"
28#include "xfs_mount.h"
29#include "xfs_da_format.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_dinode.h"
46#include "xfs_error.h"
47#include "xfs_dir2.h"
48
49#define BLK_AVG(blk1, blk2) ((blk1+blk2) >> 1)
50
51STATIC int
52xlog_find_zeroed(
53 struct xlog *,
54 xfs_daddr_t *);
55STATIC int
56xlog_clear_stale_blocks(
57 struct xlog *,
58 xfs_lsn_t);
59#if defined(DEBUG)
60STATIC void
61xlog_recover_check_summary(
62 struct xlog *);
63#else
64#define xlog_recover_check_summary(log)
65#endif
66
67/*
68 * This structure is used during recovery to record the buf log items which
69 * have been canceled and should not be replayed.
70 */
71struct xfs_buf_cancel {
72 xfs_daddr_t bc_blkno;
73 uint bc_len;
74 int bc_refcount;
75 struct list_head bc_list;
76};
77
78/*
79 * Sector aligned buffer routines for buffer create/read/write/access
80 */
81
82/*
83 * Verify the given count of basic blocks is valid number of blocks
84 * to specify for an operation involving the given XFS log buffer.
85 * Returns nonzero if the count is valid, 0 otherwise.
86 */
87
88static inline int
89xlog_buf_bbcount_valid(
90 struct xlog *log,
91 int bbcount)
92{
93 return bbcount > 0 && bbcount <= log->l_logBBsize;
94}
95
96/*
97 * Allocate a buffer to hold log data. The buffer needs to be able
98 * to map to a range of nbblks basic blocks at any valid (basic
99 * block) offset within the log.
100 */
101STATIC xfs_buf_t *
102xlog_get_bp(
103 struct xlog *log,
104 int nbblks)
105{
106 struct xfs_buf *bp;
107
108 if (!xlog_buf_bbcount_valid(log, nbblks)) {
109 xfs_warn(log->l_mp, "Invalid block length (0x%x) for buffer",
110 nbblks);
111 XFS_ERROR_REPORT(__func__, XFS_ERRLEVEL_HIGH, log->l_mp);
112 return NULL;
113 }
114
115 /*
116 * We do log I/O in units of log sectors (a power-of-2
117 * multiple of the basic block size), so we round up the
118 * requested size to accommodate the basic blocks required
119 * for complete log sectors.
120 *
121 * In addition, the buffer may be used for a non-sector-
122 * aligned block offset, in which case an I/O of the
123 * requested size could extend beyond the end of the
124 * buffer. If the requested size is only 1 basic block it
125 * will never straddle a sector boundary, so this won't be
126 * an issue. Nor will this be a problem if the log I/O is
127 * done in basic blocks (sector size 1). But otherwise we
128 * extend the buffer by one extra log sector to ensure
129 * there's space to accommodate this possibility.
130 */
131 if (nbblks > 1 && log->l_sectBBsize > 1)
132 nbblks += log->l_sectBBsize;
133 nbblks = round_up(nbblks, log->l_sectBBsize);
134
135 bp = xfs_buf_get_uncached(log->l_mp->m_logdev_targp, nbblks, 0);
136 if (bp)
137 xfs_buf_unlock(bp);
138 return bp;
139}
140
141STATIC void
142xlog_put_bp(
143 xfs_buf_t *bp)
144{
145 xfs_buf_free(bp);
146}
147
148/*
149 * Return the address of the start of the given block number's data
150 * in a log buffer. The buffer covers a log sector-aligned region.
151 */
152STATIC xfs_caddr_t
153xlog_align(
154 struct xlog *log,
155 xfs_daddr_t blk_no,
156 int nbblks,
157 struct xfs_buf *bp)
158{
159 xfs_daddr_t offset = blk_no & ((xfs_daddr_t)log->l_sectBBsize - 1);
160
161 ASSERT(offset + nbblks <= bp->b_length);
162 return bp->b_addr + BBTOB(offset);
163}
164
165
166/*
167 * nbblks should be uint, but oh well. Just want to catch that 32-bit length.
168 */
169STATIC int
170xlog_bread_noalign(
171 struct xlog *log,
172 xfs_daddr_t blk_no,
173 int nbblks,
174 struct xfs_buf *bp)
175{
176 int error;
177
178 if (!xlog_buf_bbcount_valid(log, nbblks)) {
179 xfs_warn(log->l_mp, "Invalid block length (0x%x) for buffer",
180 nbblks);
181 XFS_ERROR_REPORT(__func__, XFS_ERRLEVEL_HIGH, log->l_mp);
182 return EFSCORRUPTED;
183 }
184
185 blk_no = round_down(blk_no, log->l_sectBBsize);
186 nbblks = round_up(nbblks, log->l_sectBBsize);
187
188 ASSERT(nbblks > 0);
189 ASSERT(nbblks <= bp->b_length);
190
191 XFS_BUF_SET_ADDR(bp, log->l_logBBstart + blk_no);
192 XFS_BUF_READ(bp);
193 bp->b_io_length = nbblks;
194 bp->b_error = 0;
195
196 if (XFS_FORCED_SHUTDOWN(log->l_mp))
197 return XFS_ERROR(EIO);
198
199 xfs_buf_iorequest(bp);
200 error = xfs_buf_iowait(bp);
201 if (error)
202 xfs_buf_ioerror_alert(bp, __func__);
203 return error;
204}
205
206STATIC int
207xlog_bread(
208 struct xlog *log,
209 xfs_daddr_t blk_no,
210 int nbblks,
211 struct xfs_buf *bp,
212 xfs_caddr_t *offset)
213{
214 int error;
215
216 error = xlog_bread_noalign(log, blk_no, nbblks, bp);
217 if (error)
218 return error;
219
220 *offset = xlog_align(log, blk_no, nbblks, bp);
221 return 0;
222}
223
224/*
225 * Read at an offset into the buffer. Returns with the buffer in it's original
226 * state regardless of the result of the read.
227 */
228STATIC int
229xlog_bread_offset(
230 struct xlog *log,
231 xfs_daddr_t blk_no, /* block to read from */
232 int nbblks, /* blocks to read */
233 struct xfs_buf *bp,
234 xfs_caddr_t offset)
235{
236 xfs_caddr_t orig_offset = bp->b_addr;
237 int orig_len = BBTOB(bp->b_length);
238 int error, error2;
239
240 error = xfs_buf_associate_memory(bp, offset, BBTOB(nbblks));
241 if (error)
242 return error;
243
244 error = xlog_bread_noalign(log, blk_no, nbblks, bp);
245
246 /* must reset buffer pointer even on error */
247 error2 = xfs_buf_associate_memory(bp, orig_offset, orig_len);
248 if (error)
249 return error;
250 return error2;
251}
252
253/*
254 * Write out the buffer at the given block for the given number of blocks.
255 * The buffer is kept locked across the write and is returned locked.
256 * This can only be used for synchronous log writes.
257 */
258STATIC int
259xlog_bwrite(
260 struct xlog *log,
261 xfs_daddr_t blk_no,
262 int nbblks,
263 struct xfs_buf *bp)
264{
265 int error;
266
267 if (!xlog_buf_bbcount_valid(log, nbblks)) {
268 xfs_warn(log->l_mp, "Invalid block length (0x%x) for buffer",
269 nbblks);
270 XFS_ERROR_REPORT(__func__, XFS_ERRLEVEL_HIGH, log->l_mp);
271 return EFSCORRUPTED;
272 }
273
274 blk_no = round_down(blk_no, log->l_sectBBsize);
275 nbblks = round_up(nbblks, log->l_sectBBsize);
276
277 ASSERT(nbblks > 0);
278 ASSERT(nbblks <= bp->b_length);
279
280 XFS_BUF_SET_ADDR(bp, log->l_logBBstart + blk_no);
281 XFS_BUF_ZEROFLAGS(bp);
282 xfs_buf_hold(bp);
283 xfs_buf_lock(bp);
284 bp->b_io_length = nbblks;
285 bp->b_error = 0;
286
287 error = xfs_bwrite(bp);
288 if (error)
289 xfs_buf_ioerror_alert(bp, __func__);
290 xfs_buf_relse(bp);
291 return error;
292}
293
294#ifdef DEBUG
295/*
296 * dump debug superblock and log record information
297 */
298STATIC void
299xlog_header_check_dump(
300 xfs_mount_t *mp,
301 xlog_rec_header_t *head)
302{
303 xfs_debug(mp, "%s: SB : uuid = %pU, fmt = %d",
304 __func__, &mp->m_sb.sb_uuid, XLOG_FMT);
305 xfs_debug(mp, " log : uuid = %pU, fmt = %d",
306 &head->h_fs_uuid, be32_to_cpu(head->h_fmt));
307}
308#else
309#define xlog_header_check_dump(mp, head)
310#endif
311
312/*
313 * check log record header for recovery
314 */
315STATIC int
316xlog_header_check_recover(
317 xfs_mount_t *mp,
318 xlog_rec_header_t *head)
319{
320 ASSERT(head->h_magicno == cpu_to_be32(XLOG_HEADER_MAGIC_NUM));
321
322 /*
323 * IRIX doesn't write the h_fmt field and leaves it zeroed
324 * (XLOG_FMT_UNKNOWN). This stops us from trying to recover
325 * a dirty log created in IRIX.
326 */
327 if (unlikely(head->h_fmt != cpu_to_be32(XLOG_FMT))) {
328 xfs_warn(mp,
329 "dirty log written in incompatible format - can't recover");
330 xlog_header_check_dump(mp, head);
331 XFS_ERROR_REPORT("xlog_header_check_recover(1)",
332 XFS_ERRLEVEL_HIGH, mp);
333 return XFS_ERROR(EFSCORRUPTED);
334 } else if (unlikely(!uuid_equal(&mp->m_sb.sb_uuid, &head->h_fs_uuid))) {
335 xfs_warn(mp,
336 "dirty log entry has mismatched uuid - can't recover");
337 xlog_header_check_dump(mp, head);
338 XFS_ERROR_REPORT("xlog_header_check_recover(2)",
339 XFS_ERRLEVEL_HIGH, mp);
340 return XFS_ERROR(EFSCORRUPTED);
341 }
342 return 0;
343}
344
345/*
346 * read the head block of the log and check the header
347 */
348STATIC int
349xlog_header_check_mount(
350 xfs_mount_t *mp,
351 xlog_rec_header_t *head)
352{
353 ASSERT(head->h_magicno == cpu_to_be32(XLOG_HEADER_MAGIC_NUM));
354
355 if (uuid_is_nil(&head->h_fs_uuid)) {
356 /*
357 * IRIX doesn't write the h_fs_uuid or h_fmt fields. If
358 * h_fs_uuid is nil, we assume this log was last mounted
359 * by IRIX and continue.
360 */
361 xfs_warn(mp, "nil uuid in log - IRIX style log");
362 } else if (unlikely(!uuid_equal(&mp->m_sb.sb_uuid, &head->h_fs_uuid))) {
363 xfs_warn(mp, "log has mismatched uuid - can't recover");
364 xlog_header_check_dump(mp, head);
365 XFS_ERROR_REPORT("xlog_header_check_mount",
366 XFS_ERRLEVEL_HIGH, mp);
367 return XFS_ERROR(EFSCORRUPTED);
368 }
369 return 0;
370}
371
372STATIC void
373xlog_recover_iodone(
374 struct xfs_buf *bp)
375{
376 if (bp->b_error) {
377 /*
378 * We're not going to bother about retrying
379 * this during recovery. One strike!
380 */
381 xfs_buf_ioerror_alert(bp, __func__);
382 xfs_force_shutdown(bp->b_target->bt_mount,
383 SHUTDOWN_META_IO_ERROR);
384 }
385 bp->b_iodone = NULL;
386 xfs_buf_ioend(bp, 0);
387}
388
389/*
390 * This routine finds (to an approximation) the first block in the physical
391 * log which contains the given cycle. It uses a binary search algorithm.
392 * Note that the algorithm can not be perfect because the disk will not
393 * necessarily be perfect.
394 */
395STATIC int
396xlog_find_cycle_start(
397 struct xlog *log,
398 struct xfs_buf *bp,
399 xfs_daddr_t first_blk,
400 xfs_daddr_t *last_blk,
401 uint cycle)
402{
403 xfs_caddr_t offset;
404 xfs_daddr_t mid_blk;
405 xfs_daddr_t end_blk;
406 uint mid_cycle;
407 int error;
408
409 end_blk = *last_blk;
410 mid_blk = BLK_AVG(first_blk, end_blk);
411 while (mid_blk != first_blk && mid_blk != end_blk) {
412 error = xlog_bread(log, mid_blk, 1, bp, &offset);
413 if (error)
414 return error;
415 mid_cycle = xlog_get_cycle(offset);
416 if (mid_cycle == cycle)
417 end_blk = mid_blk; /* last_half_cycle == mid_cycle */
418 else
419 first_blk = mid_blk; /* first_half_cycle == mid_cycle */
420 mid_blk = BLK_AVG(first_blk, end_blk);
421 }
422 ASSERT((mid_blk == first_blk && mid_blk+1 == end_blk) ||
423 (mid_blk == end_blk && mid_blk-1 == first_blk));
424
425 *last_blk = end_blk;
426
427 return 0;
428}
429
430/*
431 * Check that a range of blocks does not contain stop_on_cycle_no.
432 * Fill in *new_blk with the block offset where such a block is
433 * found, or with -1 (an invalid block number) if there is no such
434 * block in the range. The scan needs to occur from front to back
435 * and the pointer into the region must be updated since a later
436 * routine will need to perform another test.
437 */
438STATIC int
439xlog_find_verify_cycle(
440 struct xlog *log,
441 xfs_daddr_t start_blk,
442 int nbblks,
443 uint stop_on_cycle_no,
444 xfs_daddr_t *new_blk)
445{
446 xfs_daddr_t i, j;
447 uint cycle;
448 xfs_buf_t *bp;
449 xfs_daddr_t bufblks;
450 xfs_caddr_t buf = NULL;
451 int error = 0;
452
453 /*
454 * Greedily allocate a buffer big enough to handle the full
455 * range of basic blocks we'll be examining. If that fails,
456 * try a smaller size. We need to be able to read at least
457 * a log sector, or we're out of luck.
458 */
459 bufblks = 1 << ffs(nbblks);
460 while (bufblks > log->l_logBBsize)
461 bufblks >>= 1;
462 while (!(bp = xlog_get_bp(log, bufblks))) {
463 bufblks >>= 1;
464 if (bufblks < log->l_sectBBsize)
465 return ENOMEM;
466 }
467
468 for (i = start_blk; i < start_blk + nbblks; i += bufblks) {
469 int bcount;
470
471 bcount = min(bufblks, (start_blk + nbblks - i));
472
473 error = xlog_bread(log, i, bcount, bp, &buf);
474 if (error)
475 goto out;
476
477 for (j = 0; j < bcount; j++) {
478 cycle = xlog_get_cycle(buf);
479 if (cycle == stop_on_cycle_no) {
480 *new_blk = i+j;
481 goto out;
482 }
483
484 buf += BBSIZE;
485 }
486 }
487
488 *new_blk = -1;
489
490out:
491 xlog_put_bp(bp);
492 return error;
493}
494
495/*
496 * Potentially backup over partial log record write.
497 *
498 * In the typical case, last_blk is the number of the block directly after
499 * a good log record. Therefore, we subtract one to get the block number
500 * of the last block in the given buffer. extra_bblks contains the number
501 * of blocks we would have read on a previous read. This happens when the
502 * last log record is split over the end of the physical log.
503 *
504 * extra_bblks is the number of blocks potentially verified on a previous
505 * call to this routine.
506 */
507STATIC int
508xlog_find_verify_log_record(
509 struct xlog *log,
510 xfs_daddr_t start_blk,
511 xfs_daddr_t *last_blk,
512 int extra_bblks)
513{
514 xfs_daddr_t i;
515 xfs_buf_t *bp;
516 xfs_caddr_t offset = NULL;
517 xlog_rec_header_t *head = NULL;
518 int error = 0;
519 int smallmem = 0;
520 int num_blks = *last_blk - start_blk;
521 int xhdrs;
522
523 ASSERT(start_blk != 0 || *last_blk != start_blk);
524
525 if (!(bp = xlog_get_bp(log, num_blks))) {
526 if (!(bp = xlog_get_bp(log, 1)))
527 return ENOMEM;
528 smallmem = 1;
529 } else {
530 error = xlog_bread(log, start_blk, num_blks, bp, &offset);
531 if (error)
532 goto out;
533 offset += ((num_blks - 1) << BBSHIFT);
534 }
535
536 for (i = (*last_blk) - 1; i >= 0; i--) {
537 if (i < start_blk) {
538 /* valid log record not found */
539 xfs_warn(log->l_mp,
540 "Log inconsistent (didn't find previous header)");
541 ASSERT(0);
542 error = XFS_ERROR(EIO);
543 goto out;
544 }
545
546 if (smallmem) {
547 error = xlog_bread(log, i, 1, bp, &offset);
548 if (error)
549 goto out;
550 }
551
552 head = (xlog_rec_header_t *)offset;
553
554 if (head->h_magicno == cpu_to_be32(XLOG_HEADER_MAGIC_NUM))
555 break;
556
557 if (!smallmem)
558 offset -= BBSIZE;
559 }
560
561 /*
562 * We hit the beginning of the physical log & still no header. Return
563 * to caller. If caller can handle a return of -1, then this routine
564 * will be called again for the end of the physical log.
565 */
566 if (i == -1) {
567 error = -1;
568 goto out;
569 }
570
571 /*
572 * We have the final block of the good log (the first block
573 * of the log record _before_ the head. So we check the uuid.
574 */
575 if ((error = xlog_header_check_mount(log->l_mp, head)))
576 goto out;
577
578 /*
579 * We may have found a log record header before we expected one.
580 * last_blk will be the 1st block # with a given cycle #. We may end
581 * up reading an entire log record. In this case, we don't want to
582 * reset last_blk. Only when last_blk points in the middle of a log
583 * record do we update last_blk.
584 */
585 if (xfs_sb_version_haslogv2(&log->l_mp->m_sb)) {
586 uint h_size = be32_to_cpu(head->h_size);
587
588 xhdrs = h_size / XLOG_HEADER_CYCLE_SIZE;
589 if (h_size % XLOG_HEADER_CYCLE_SIZE)
590 xhdrs++;
591 } else {
592 xhdrs = 1;
593 }
594
595 if (*last_blk - i + extra_bblks !=
596 BTOBB(be32_to_cpu(head->h_len)) + xhdrs)
597 *last_blk = i;
598
599out:
600 xlog_put_bp(bp);
601 return error;
602}
603
604/*
605 * Head is defined to be the point of the log where the next log write
606 * could go. This means that incomplete LR writes at the end are
607 * eliminated when calculating the head. We aren't guaranteed that previous
608 * LR have complete transactions. We only know that a cycle number of
609 * current cycle number -1 won't be present in the log if we start writing
610 * from our current block number.
611 *
612 * last_blk contains the block number of the first block with a given
613 * cycle number.
614 *
615 * Return: zero if normal, non-zero if error.
616 */
617STATIC int
618xlog_find_head(
619 struct xlog *log,
620 xfs_daddr_t *return_head_blk)
621{
622 xfs_buf_t *bp;
623 xfs_caddr_t offset;
624 xfs_daddr_t new_blk, first_blk, start_blk, last_blk, head_blk;
625 int num_scan_bblks;
626 uint first_half_cycle, last_half_cycle;
627 uint stop_on_cycle;
628 int error, log_bbnum = log->l_logBBsize;
629
630 /* Is the end of the log device zeroed? */
631 if ((error = xlog_find_zeroed(log, &first_blk)) == -1) {
632 *return_head_blk = first_blk;
633
634 /* Is the whole lot zeroed? */
635 if (!first_blk) {
636 /* Linux XFS shouldn't generate totally zeroed logs -
637 * mkfs etc write a dummy unmount record to a fresh
638 * log so we can store the uuid in there
639 */
640 xfs_warn(log->l_mp, "totally zeroed log");
641 }
642
643 return 0;
644 } else if (error) {
645 xfs_warn(log->l_mp, "empty log check failed");
646 return error;
647 }
648
649 first_blk = 0; /* get cycle # of 1st block */
650 bp = xlog_get_bp(log, 1);
651 if (!bp)
652 return ENOMEM;
653
654 error = xlog_bread(log, 0, 1, bp, &offset);
655 if (error)
656 goto bp_err;
657
658 first_half_cycle = xlog_get_cycle(offset);
659
660 last_blk = head_blk = log_bbnum - 1; /* get cycle # of last block */
661 error = xlog_bread(log, last_blk, 1, bp, &offset);
662 if (error)
663 goto bp_err;
664
665 last_half_cycle = xlog_get_cycle(offset);
666 ASSERT(last_half_cycle != 0);
667
668 /*
669 * If the 1st half cycle number is equal to the last half cycle number,
670 * then the entire log is stamped with the same cycle number. In this
671 * case, head_blk can't be set to zero (which makes sense). The below
672 * math doesn't work out properly with head_blk equal to zero. Instead,
673 * we set it to log_bbnum which is an invalid block number, but this
674 * value makes the math correct. If head_blk doesn't changed through
675 * all the tests below, *head_blk is set to zero at the very end rather
676 * than log_bbnum. In a sense, log_bbnum and zero are the same block
677 * in a circular file.
678 */
679 if (first_half_cycle == last_half_cycle) {
680 /*
681 * In this case we believe that the entire log should have
682 * cycle number last_half_cycle. We need to scan backwards
683 * from the end verifying that there are no holes still
684 * containing last_half_cycle - 1. If we find such a hole,
685 * then the start of that hole will be the new head. The
686 * simple case looks like
687 * x | x ... | x - 1 | x
688 * Another case that fits this picture would be
689 * x | x + 1 | x ... | x
690 * In this case the head really is somewhere at the end of the
691 * log, as one of the latest writes at the beginning was
692 * incomplete.
693 * One more case is
694 * x | x + 1 | x ... | x - 1 | x
695 * This is really the combination of the above two cases, and
696 * the head has to end up at the start of the x-1 hole at the
697 * end of the log.
698 *
699 * In the 256k log case, we will read from the beginning to the
700 * end of the log and search for cycle numbers equal to x-1.
701 * We don't worry about the x+1 blocks that we encounter,
702 * because we know that they cannot be the head since the log
703 * started with x.
704 */
705 head_blk = log_bbnum;
706 stop_on_cycle = last_half_cycle - 1;
707 } else {
708 /*
709 * In this case we want to find the first block with cycle
710 * number matching last_half_cycle. We expect the log to be
711 * some variation on
712 * x + 1 ... | x ... | x
713 * The first block with cycle number x (last_half_cycle) will
714 * be where the new head belongs. First we do a binary search
715 * for the first occurrence of last_half_cycle. The binary
716 * search may not be totally accurate, so then we scan back
717 * from there looking for occurrences of last_half_cycle before
718 * us. If that backwards scan wraps around the beginning of
719 * the log, then we look for occurrences of last_half_cycle - 1
720 * at the end of the log. The cases we're looking for look
721 * like
722 * v binary search stopped here
723 * x + 1 ... | x | x + 1 | x ... | x
724 * ^ but we want to locate this spot
725 * or
726 * <---------> less than scan distance
727 * x + 1 ... | x ... | x - 1 | x
728 * ^ we want to locate this spot
729 */
730 stop_on_cycle = last_half_cycle;
731 if ((error = xlog_find_cycle_start(log, bp, first_blk,
732 &head_blk, last_half_cycle)))
733 goto bp_err;
734 }
735
736 /*
737 * Now validate the answer. Scan back some number of maximum possible
738 * blocks and make sure each one has the expected cycle number. The
739 * maximum is determined by the total possible amount of buffering
740 * in the in-core log. The following number can be made tighter if
741 * we actually look at the block size of the filesystem.
742 */
743 num_scan_bblks = XLOG_TOTAL_REC_SHIFT(log);
744 if (head_blk >= num_scan_bblks) {
745 /*
746 * We are guaranteed that the entire check can be performed
747 * in one buffer.
748 */
749 start_blk = head_blk - num_scan_bblks;
750 if ((error = xlog_find_verify_cycle(log,
751 start_blk, num_scan_bblks,
752 stop_on_cycle, &new_blk)))
753 goto bp_err;
754 if (new_blk != -1)
755 head_blk = new_blk;
756 } else { /* need to read 2 parts of log */
757 /*
758 * We are going to scan backwards in the log in two parts.
759 * First we scan the physical end of the log. In this part
760 * of the log, we are looking for blocks with cycle number
761 * last_half_cycle - 1.
762 * If we find one, then we know that the log starts there, as
763 * we've found a hole that didn't get written in going around
764 * the end of the physical log. The simple case for this is
765 * x + 1 ... | x ... | x - 1 | x
766 * <---------> less than scan distance
767 * If all of the blocks at the end of the log have cycle number
768 * last_half_cycle, then we check the blocks at the start of
769 * the log looking for occurrences of last_half_cycle. If we
770 * find one, then our current estimate for the location of the
771 * first occurrence of last_half_cycle is wrong and we move
772 * back to the hole we've found. This case looks like
773 * x + 1 ... | x | x + 1 | x ...
774 * ^ binary search stopped here
775 * Another case we need to handle that only occurs in 256k
776 * logs is
777 * x + 1 ... | x ... | x+1 | x ...
778 * ^ binary search stops here
779 * In a 256k log, the scan at the end of the log will see the
780 * x + 1 blocks. We need to skip past those since that is
781 * certainly not the head of the log. By searching for
782 * last_half_cycle-1 we accomplish that.
783 */
784 ASSERT(head_blk <= INT_MAX &&
785 (xfs_daddr_t) num_scan_bblks >= head_blk);
786 start_blk = log_bbnum - (num_scan_bblks - head_blk);
787 if ((error = xlog_find_verify_cycle(log, start_blk,
788 num_scan_bblks - (int)head_blk,
789 (stop_on_cycle - 1), &new_blk)))
790 goto bp_err;
791 if (new_blk != -1) {
792 head_blk = new_blk;
793 goto validate_head;
794 }
795
796 /*
797 * Scan beginning of log now. The last part of the physical
798 * log is good. This scan needs to verify that it doesn't find
799 * the last_half_cycle.
800 */
801 start_blk = 0;
802 ASSERT(head_blk <= INT_MAX);
803 if ((error = xlog_find_verify_cycle(log,
804 start_blk, (int)head_blk,
805 stop_on_cycle, &new_blk)))
806 goto bp_err;
807 if (new_blk != -1)
808 head_blk = new_blk;
809 }
810
811validate_head:
812 /*
813 * Now we need to make sure head_blk is not pointing to a block in
814 * the middle of a log record.
815 */
816 num_scan_bblks = XLOG_REC_SHIFT(log);
817 if (head_blk >= num_scan_bblks) {
818 start_blk = head_blk - num_scan_bblks; /* don't read head_blk */
819
820 /* start ptr at last block ptr before head_blk */
821 if ((error = xlog_find_verify_log_record(log, start_blk,
822 &head_blk, 0)) == -1) {
823 error = XFS_ERROR(EIO);
824 goto bp_err;
825 } else if (error)
826 goto bp_err;
827 } else {
828 start_blk = 0;
829 ASSERT(head_blk <= INT_MAX);
830 if ((error = xlog_find_verify_log_record(log, start_blk,
831 &head_blk, 0)) == -1) {
832 /* We hit the beginning of the log during our search */
833 start_blk = log_bbnum - (num_scan_bblks - head_blk);
834 new_blk = log_bbnum;
835 ASSERT(start_blk <= INT_MAX &&
836 (xfs_daddr_t) log_bbnum-start_blk >= 0);
837 ASSERT(head_blk <= INT_MAX);
838 if ((error = xlog_find_verify_log_record(log,
839 start_blk, &new_blk,
840 (int)head_blk)) == -1) {
841 error = XFS_ERROR(EIO);
842 goto bp_err;
843 } else if (error)
844 goto bp_err;
845 if (new_blk != log_bbnum)
846 head_blk = new_blk;
847 } else if (error)
848 goto bp_err;
849 }
850
851 xlog_put_bp(bp);
852 if (head_blk == log_bbnum)
853 *return_head_blk = 0;
854 else
855 *return_head_blk = head_blk;
856 /*
857 * When returning here, we have a good block number. Bad block
858 * means that during a previous crash, we didn't have a clean break
859 * from cycle number N to cycle number N-1. In this case, we need
860 * to find the first block with cycle number N-1.
861 */
862 return 0;
863
864 bp_err:
865 xlog_put_bp(bp);
866
867 if (error)
868 xfs_warn(log->l_mp, "failed to find log head");
869 return error;
870}
871
872/*
873 * Find the sync block number or the tail of the log.
874 *
875 * This will be the block number of the last record to have its
876 * associated buffers synced to disk. Every log record header has
877 * a sync lsn embedded in it. LSNs hold block numbers, so it is easy
878 * to get a sync block number. The only concern is to figure out which
879 * log record header to believe.
880 *
881 * The following algorithm uses the log record header with the largest
882 * lsn. The entire log record does not need to be valid. We only care
883 * that the header is valid.
884 *
885 * We could speed up search by using current head_blk buffer, but it is not
886 * available.
887 */
888STATIC int
889xlog_find_tail(
890 struct xlog *log,
891 xfs_daddr_t *head_blk,
892 xfs_daddr_t *tail_blk)
893{
894 xlog_rec_header_t *rhead;
895 xlog_op_header_t *op_head;
896 xfs_caddr_t offset = NULL;
897 xfs_buf_t *bp;
898 int error, i, found;
899 xfs_daddr_t umount_data_blk;
900 xfs_daddr_t after_umount_blk;
901 xfs_lsn_t tail_lsn;
902 int hblks;
903
904 found = 0;
905
906 /*
907 * Find previous log record
908 */
909 if ((error = xlog_find_head(log, head_blk)))
910 return error;
911
912 bp = xlog_get_bp(log, 1);
913 if (!bp)
914 return ENOMEM;
915 if (*head_blk == 0) { /* special case */
916 error = xlog_bread(log, 0, 1, bp, &offset);
917 if (error)
918 goto done;
919
920 if (xlog_get_cycle(offset) == 0) {
921 *tail_blk = 0;
922 /* leave all other log inited values alone */
923 goto done;
924 }
925 }
926
927 /*
928 * Search backwards looking for log record header block
929 */
930 ASSERT(*head_blk < INT_MAX);
931 for (i = (int)(*head_blk) - 1; i >= 0; i--) {
932 error = xlog_bread(log, i, 1, bp, &offset);
933 if (error)
934 goto done;
935
936 if (*(__be32 *)offset == cpu_to_be32(XLOG_HEADER_MAGIC_NUM)) {
937 found = 1;
938 break;
939 }
940 }
941 /*
942 * If we haven't found the log record header block, start looking
943 * again from the end of the physical log. XXXmiken: There should be
944 * a check here to make sure we didn't search more than N blocks in
945 * the previous code.
946 */
947 if (!found) {
948 for (i = log->l_logBBsize - 1; i >= (int)(*head_blk); i--) {
949 error = xlog_bread(log, i, 1, bp, &offset);
950 if (error)
951 goto done;
952
953 if (*(__be32 *)offset ==
954 cpu_to_be32(XLOG_HEADER_MAGIC_NUM)) {
955 found = 2;
956 break;
957 }
958 }
959 }
960 if (!found) {
961 xfs_warn(log->l_mp, "%s: couldn't find sync record", __func__);
962 xlog_put_bp(bp);
963 ASSERT(0);
964 return XFS_ERROR(EIO);
965 }
966
967 /* find blk_no of tail of log */
968 rhead = (xlog_rec_header_t *)offset;
969 *tail_blk = BLOCK_LSN(be64_to_cpu(rhead->h_tail_lsn));
970
971 /*
972 * Reset log values according to the state of the log when we
973 * crashed. In the case where head_blk == 0, we bump curr_cycle
974 * one because the next write starts a new cycle rather than
975 * continuing the cycle of the last good log record. At this
976 * point we have guaranteed that all partial log records have been
977 * accounted for. Therefore, we know that the last good log record
978 * written was complete and ended exactly on the end boundary
979 * of the physical log.
980 */
981 log->l_prev_block = i;
982 log->l_curr_block = (int)*head_blk;
983 log->l_curr_cycle = be32_to_cpu(rhead->h_cycle);
984 if (found == 2)
985 log->l_curr_cycle++;
986 atomic64_set(&log->l_tail_lsn, be64_to_cpu(rhead->h_tail_lsn));
987 atomic64_set(&log->l_last_sync_lsn, be64_to_cpu(rhead->h_lsn));
988 xlog_assign_grant_head(&log->l_reserve_head.grant, log->l_curr_cycle,
989 BBTOB(log->l_curr_block));
990 xlog_assign_grant_head(&log->l_write_head.grant, log->l_curr_cycle,
991 BBTOB(log->l_curr_block));
992
993 /*
994 * Look for unmount record. If we find it, then we know there
995 * was a clean unmount. Since 'i' could be the last block in
996 * the physical log, we convert to a log block before comparing
997 * to the head_blk.
998 *
999 * Save the current tail lsn to use to pass to
1000 * xlog_clear_stale_blocks() below. We won't want to clear the
1001 * unmount record if there is one, so we pass the lsn of the
1002 * unmount record rather than the block after it.
1003 */
1004 if (xfs_sb_version_haslogv2(&log->l_mp->m_sb)) {
1005 int h_size = be32_to_cpu(rhead->h_size);
1006 int h_version = be32_to_cpu(rhead->h_version);
1007
1008 if ((h_version & XLOG_VERSION_2) &&
1009 (h_size > XLOG_HEADER_CYCLE_SIZE)) {
1010 hblks = h_size / XLOG_HEADER_CYCLE_SIZE;
1011 if (h_size % XLOG_HEADER_CYCLE_SIZE)
1012 hblks++;
1013 } else {
1014 hblks = 1;
1015 }
1016 } else {
1017 hblks = 1;
1018 }
1019 after_umount_blk = (i + hblks + (int)
1020 BTOBB(be32_to_cpu(rhead->h_len))) % log->l_logBBsize;
1021 tail_lsn = atomic64_read(&log->l_tail_lsn);
1022 if (*head_blk == after_umount_blk &&
1023 be32_to_cpu(rhead->h_num_logops) == 1) {
1024 umount_data_blk = (i + hblks) % log->l_logBBsize;
1025 error = xlog_bread(log, umount_data_blk, 1, bp, &offset);
1026 if (error)
1027 goto done;
1028
1029 op_head = (xlog_op_header_t *)offset;
1030 if (op_head->oh_flags & XLOG_UNMOUNT_TRANS) {
1031 /*
1032 * Set tail and last sync so that newly written
1033 * log records will point recovery to after the
1034 * current unmount record.
1035 */
1036 xlog_assign_atomic_lsn(&log->l_tail_lsn,
1037 log->l_curr_cycle, after_umount_blk);
1038 xlog_assign_atomic_lsn(&log->l_last_sync_lsn,
1039 log->l_curr_cycle, after_umount_blk);
1040 *tail_blk = after_umount_blk;
1041
1042 /*
1043 * Note that the unmount was clean. If the unmount
1044 * was not clean, we need to know this to rebuild the
1045 * superblock counters from the perag headers if we
1046 * have a filesystem using non-persistent counters.
1047 */
1048 log->l_mp->m_flags |= XFS_MOUNT_WAS_CLEAN;
1049 }
1050 }
1051
1052 /*
1053 * Make sure that there are no blocks in front of the head
1054 * with the same cycle number as the head. This can happen
1055 * because we allow multiple outstanding log writes concurrently,
1056 * and the later writes might make it out before earlier ones.
1057 *
1058 * We use the lsn from before modifying it so that we'll never
1059 * overwrite the unmount record after a clean unmount.
1060 *
1061 * Do this only if we are going to recover the filesystem
1062 *
1063 * NOTE: This used to say "if (!readonly)"
1064 * However on Linux, we can & do recover a read-only filesystem.
1065 * We only skip recovery if NORECOVERY is specified on mount,
1066 * in which case we would not be here.
1067 *
1068 * But... if the -device- itself is readonly, just skip this.
1069 * We can't recover this device anyway, so it won't matter.
1070 */
1071 if (!xfs_readonly_buftarg(log->l_mp->m_logdev_targp))
1072 error = xlog_clear_stale_blocks(log, tail_lsn);
1073
1074done:
1075 xlog_put_bp(bp);
1076
1077 if (error)
1078 xfs_warn(log->l_mp, "failed to locate log tail");
1079 return error;
1080}
1081
1082/*
1083 * Is the log zeroed at all?
1084 *
1085 * The last binary search should be changed to perform an X block read
1086 * once X becomes small enough. You can then search linearly through
1087 * the X blocks. This will cut down on the number of reads we need to do.
1088 *
1089 * If the log is partially zeroed, this routine will pass back the blkno
1090 * of the first block with cycle number 0. It won't have a complete LR
1091 * preceding it.
1092 *
1093 * Return:
1094 * 0 => the log is completely written to
1095 * -1 => use *blk_no as the first block of the log
1096 * >0 => error has occurred
1097 */
1098STATIC int
1099xlog_find_zeroed(
1100 struct xlog *log,
1101 xfs_daddr_t *blk_no)
1102{
1103 xfs_buf_t *bp;
1104 xfs_caddr_t offset;
1105 uint first_cycle, last_cycle;
1106 xfs_daddr_t new_blk, last_blk, start_blk;
1107 xfs_daddr_t num_scan_bblks;
1108 int error, log_bbnum = log->l_logBBsize;
1109
1110 *blk_no = 0;
1111
1112 /* check totally zeroed log */
1113 bp = xlog_get_bp(log, 1);
1114 if (!bp)
1115 return ENOMEM;
1116 error = xlog_bread(log, 0, 1, bp, &offset);
1117 if (error)
1118 goto bp_err;
1119
1120 first_cycle = xlog_get_cycle(offset);
1121 if (first_cycle == 0) { /* completely zeroed log */
1122 *blk_no = 0;
1123 xlog_put_bp(bp);
1124 return -1;
1125 }
1126
1127 /* check partially zeroed log */
1128 error = xlog_bread(log, log_bbnum-1, 1, bp, &offset);
1129 if (error)
1130 goto bp_err;
1131
1132 last_cycle = xlog_get_cycle(offset);
1133 if (last_cycle != 0) { /* log completely written to */
1134 xlog_put_bp(bp);
1135 return 0;
1136 } else if (first_cycle != 1) {
1137 /*
1138 * If the cycle of the last block is zero, the cycle of
1139 * the first block must be 1. If it's not, maybe we're
1140 * not looking at a log... Bail out.
1141 */
1142 xfs_warn(log->l_mp,
1143 "Log inconsistent or not a log (last==0, first!=1)");
1144 error = XFS_ERROR(EINVAL);
1145 goto bp_err;
1146 }
1147
1148 /* we have a partially zeroed log */
1149 last_blk = log_bbnum-1;
1150 if ((error = xlog_find_cycle_start(log, bp, 0, &last_blk, 0)))
1151 goto bp_err;
1152
1153 /*
1154 * Validate the answer. Because there is no way to guarantee that
1155 * the entire log is made up of log records which are the same size,
1156 * we scan over the defined maximum blocks. At this point, the maximum
1157 * is not chosen to mean anything special. XXXmiken
1158 */
1159 num_scan_bblks = XLOG_TOTAL_REC_SHIFT(log);
1160 ASSERT(num_scan_bblks <= INT_MAX);
1161
1162 if (last_blk < num_scan_bblks)
1163 num_scan_bblks = last_blk;
1164 start_blk = last_blk - num_scan_bblks;
1165
1166 /*
1167 * We search for any instances of cycle number 0 that occur before
1168 * our current estimate of the head. What we're trying to detect is
1169 * 1 ... | 0 | 1 | 0...
1170 * ^ binary search ends here
1171 */
1172 if ((error = xlog_find_verify_cycle(log, start_blk,
1173 (int)num_scan_bblks, 0, &new_blk)))
1174 goto bp_err;
1175 if (new_blk != -1)
1176 last_blk = new_blk;
1177
1178 /*
1179 * Potentially backup over partial log record write. We don't need
1180 * to search the end of the log because we know it is zero.
1181 */
1182 if ((error = xlog_find_verify_log_record(log, start_blk,
1183 &last_blk, 0)) == -1) {
1184 error = XFS_ERROR(EIO);
1185 goto bp_err;
1186 } else if (error)
1187 goto bp_err;
1188
1189 *blk_no = last_blk;
1190bp_err:
1191 xlog_put_bp(bp);
1192 if (error)
1193 return error;
1194 return -1;
1195}
1196
1197/*
1198 * These are simple subroutines used by xlog_clear_stale_blocks() below
1199 * to initialize a buffer full of empty log record headers and write
1200 * them into the log.
1201 */
1202STATIC void
1203xlog_add_record(
1204 struct xlog *log,
1205 xfs_caddr_t buf,
1206 int cycle,
1207 int block,
1208 int tail_cycle,
1209 int tail_block)
1210{
1211 xlog_rec_header_t *recp = (xlog_rec_header_t *)buf;
1212
1213 memset(buf, 0, BBSIZE);
1214 recp->h_magicno = cpu_to_be32(XLOG_HEADER_MAGIC_NUM);
1215 recp->h_cycle = cpu_to_be32(cycle);
1216 recp->h_version = cpu_to_be32(
1217 xfs_sb_version_haslogv2(&log->l_mp->m_sb) ? 2 : 1);
1218 recp->h_lsn = cpu_to_be64(xlog_assign_lsn(cycle, block));
1219 recp->h_tail_lsn = cpu_to_be64(xlog_assign_lsn(tail_cycle, tail_block));
1220 recp->h_fmt = cpu_to_be32(XLOG_FMT);
1221 memcpy(&recp->h_fs_uuid, &log->l_mp->m_sb.sb_uuid, sizeof(uuid_t));
1222}
1223
1224STATIC int
1225xlog_write_log_records(
1226 struct xlog *log,
1227 int cycle,
1228 int start_block,
1229 int blocks,
1230 int tail_cycle,
1231 int tail_block)
1232{
1233 xfs_caddr_t offset;
1234 xfs_buf_t *bp;
1235 int balign, ealign;
1236 int sectbb = log->l_sectBBsize;
1237 int end_block = start_block + blocks;
1238 int bufblks;
1239 int error = 0;
1240 int i, j = 0;
1241
1242 /*
1243 * Greedily allocate a buffer big enough to handle the full
1244 * range of basic blocks to be written. If that fails, try
1245 * a smaller size. We need to be able to write at least a
1246 * log sector, or we're out of luck.
1247 */
1248 bufblks = 1 << ffs(blocks);
1249 while (bufblks > log->l_logBBsize)
1250 bufblks >>= 1;
1251 while (!(bp = xlog_get_bp(log, bufblks))) {
1252 bufblks >>= 1;
1253 if (bufblks < sectbb)
1254 return ENOMEM;
1255 }
1256
1257 /* We may need to do a read at the start to fill in part of
1258 * the buffer in the starting sector not covered by the first
1259 * write below.
1260 */
1261 balign = round_down(start_block, sectbb);
1262 if (balign != start_block) {
1263 error = xlog_bread_noalign(log, start_block, 1, bp);
1264 if (error)
1265 goto out_put_bp;
1266
1267 j = start_block - balign;
1268 }
1269
1270 for (i = start_block; i < end_block; i += bufblks) {
1271 int bcount, endcount;
1272
1273 bcount = min(bufblks, end_block - start_block);
1274 endcount = bcount - j;
1275
1276 /* We may need to do a read at the end to fill in part of
1277 * the buffer in the final sector not covered by the write.
1278 * If this is the same sector as the above read, skip it.
1279 */
1280 ealign = round_down(end_block, sectbb);
1281 if (j == 0 && (start_block + endcount > ealign)) {
1282 offset = bp->b_addr + BBTOB(ealign - start_block);
1283 error = xlog_bread_offset(log, ealign, sectbb,
1284 bp, offset);
1285 if (error)
1286 break;
1287
1288 }
1289
1290 offset = xlog_align(log, start_block, endcount, bp);
1291 for (; j < endcount; j++) {
1292 xlog_add_record(log, offset, cycle, i+j,
1293 tail_cycle, tail_block);
1294 offset += BBSIZE;
1295 }
1296 error = xlog_bwrite(log, start_block, endcount, bp);
1297 if (error)
1298 break;
1299 start_block += endcount;
1300 j = 0;
1301 }
1302
1303 out_put_bp:
1304 xlog_put_bp(bp);
1305 return error;
1306}
1307
1308/*
1309 * This routine is called to blow away any incomplete log writes out
1310 * in front of the log head. We do this so that we won't become confused
1311 * if we come up, write only a little bit more, and then crash again.
1312 * If we leave the partial log records out there, this situation could
1313 * cause us to think those partial writes are valid blocks since they
1314 * have the current cycle number. We get rid of them by overwriting them
1315 * with empty log records with the old cycle number rather than the
1316 * current one.
1317 *
1318 * The tail lsn is passed in rather than taken from
1319 * the log so that we will not write over the unmount record after a
1320 * clean unmount in a 512 block log. Doing so would leave the log without
1321 * any valid log records in it until a new one was written. If we crashed
1322 * during that time we would not be able to recover.
1323 */
1324STATIC int
1325xlog_clear_stale_blocks(
1326 struct xlog *log,
1327 xfs_lsn_t tail_lsn)
1328{
1329 int tail_cycle, head_cycle;
1330 int tail_block, head_block;
1331 int tail_distance, max_distance;
1332 int distance;
1333 int error;
1334
1335 tail_cycle = CYCLE_LSN(tail_lsn);
1336 tail_block = BLOCK_LSN(tail_lsn);
1337 head_cycle = log->l_curr_cycle;
1338 head_block = log->l_curr_block;
1339
1340 /*
1341 * Figure out the distance between the new head of the log
1342 * and the tail. We want to write over any blocks beyond the
1343 * head that we may have written just before the crash, but
1344 * we don't want to overwrite the tail of the log.
1345 */
1346 if (head_cycle == tail_cycle) {
1347 /*
1348 * The tail is behind the head in the physical log,
1349 * so the distance from the head to the tail is the
1350 * distance from the head to the end of the log plus
1351 * the distance from the beginning of the log to the
1352 * tail.
1353 */
1354 if (unlikely(head_block < tail_block || head_block >= log->l_logBBsize)) {
1355 XFS_ERROR_REPORT("xlog_clear_stale_blocks(1)",
1356 XFS_ERRLEVEL_LOW, log->l_mp);
1357 return XFS_ERROR(EFSCORRUPTED);
1358 }
1359 tail_distance = tail_block + (log->l_logBBsize - head_block);
1360 } else {
1361 /*
1362 * The head is behind the tail in the physical log,
1363 * so the distance from the head to the tail is just
1364 * the tail block minus the head block.
1365 */
1366 if (unlikely(head_block >= tail_block || head_cycle != (tail_cycle + 1))){
1367 XFS_ERROR_REPORT("xlog_clear_stale_blocks(2)",
1368 XFS_ERRLEVEL_LOW, log->l_mp);
1369 return XFS_ERROR(EFSCORRUPTED);
1370 }
1371 tail_distance = tail_block - head_block;
1372 }
1373
1374 /*
1375 * If the head is right up against the tail, we can't clear
1376 * anything.
1377 */
1378 if (tail_distance <= 0) {
1379 ASSERT(tail_distance == 0);
1380 return 0;
1381 }
1382
1383 max_distance = XLOG_TOTAL_REC_SHIFT(log);
1384 /*
1385 * Take the smaller of the maximum amount of outstanding I/O
1386 * we could have and the distance to the tail to clear out.
1387 * We take the smaller so that we don't overwrite the tail and
1388 * we don't waste all day writing from the head to the tail
1389 * for no reason.
1390 */
1391 max_distance = MIN(max_distance, tail_distance);
1392
1393 if ((head_block + max_distance) <= log->l_logBBsize) {
1394 /*
1395 * We can stomp all the blocks we need to without
1396 * wrapping around the end of the log. Just do it
1397 * in a single write. Use the cycle number of the
1398 * current cycle minus one so that the log will look like:
1399 * n ... | n - 1 ...
1400 */
1401 error = xlog_write_log_records(log, (head_cycle - 1),
1402 head_block, max_distance, tail_cycle,
1403 tail_block);
1404 if (error)
1405 return error;
1406 } else {
1407 /*
1408 * We need to wrap around the end of the physical log in
1409 * order to clear all the blocks. Do it in two separate
1410 * I/Os. The first write should be from the head to the
1411 * end of the physical log, and it should use the current
1412 * cycle number minus one just like above.
1413 */
1414 distance = log->l_logBBsize - head_block;
1415 error = xlog_write_log_records(log, (head_cycle - 1),
1416 head_block, distance, tail_cycle,
1417 tail_block);
1418
1419 if (error)
1420 return error;
1421
1422 /*
1423 * Now write the blocks at the start of the physical log.
1424 * This writes the remainder of the blocks we want to clear.
1425 * It uses the current cycle number since we're now on the
1426 * same cycle as the head so that we get:
1427 * n ... n ... | n - 1 ...
1428 * ^^^^^ blocks we're writing
1429 */
1430 distance = max_distance - (log->l_logBBsize - head_block);
1431 error = xlog_write_log_records(log, head_cycle, 0, distance,
1432 tail_cycle, tail_block);
1433 if (error)
1434 return error;
1435 }
1436
1437 return 0;
1438}
1439
1440/******************************************************************************
1441 *
1442 * Log recover routines
1443 *
1444 ******************************************************************************
1445 */
1446
1447STATIC xlog_recover_t *
1448xlog_recover_find_tid(
1449 struct hlist_head *head,
1450 xlog_tid_t tid)
1451{
1452 xlog_recover_t *trans;
1453
1454 hlist_for_each_entry(trans, head, r_list) {
1455 if (trans->r_log_tid == tid)
1456 return trans;
1457 }
1458 return NULL;
1459}
1460
1461STATIC void
1462xlog_recover_new_tid(
1463 struct hlist_head *head,
1464 xlog_tid_t tid,
1465 xfs_lsn_t lsn)
1466{
1467 xlog_recover_t *trans;
1468
1469 trans = kmem_zalloc(sizeof(xlog_recover_t), KM_SLEEP);
1470 trans->r_log_tid = tid;
1471 trans->r_lsn = lsn;
1472 INIT_LIST_HEAD(&trans->r_itemq);
1473
1474 INIT_HLIST_NODE(&trans->r_list);
1475 hlist_add_head(&trans->r_list, head);
1476}
1477
1478STATIC void
1479xlog_recover_add_item(
1480 struct list_head *head)
1481{
1482 xlog_recover_item_t *item;
1483
1484 item = kmem_zalloc(sizeof(xlog_recover_item_t), KM_SLEEP);
1485 INIT_LIST_HEAD(&item->ri_list);
1486 list_add_tail(&item->ri_list, head);
1487}
1488
1489STATIC int
1490xlog_recover_add_to_cont_trans(
1491 struct xlog *log,
1492 struct xlog_recover *trans,
1493 xfs_caddr_t dp,
1494 int len)
1495{
1496 xlog_recover_item_t *item;
1497 xfs_caddr_t ptr, old_ptr;
1498 int old_len;
1499
1500 if (list_empty(&trans->r_itemq)) {
1501 /* finish copying rest of trans header */
1502 xlog_recover_add_item(&trans->r_itemq);
1503 ptr = (xfs_caddr_t) &trans->r_theader +
1504 sizeof(xfs_trans_header_t) - len;
1505 memcpy(ptr, dp, len); /* d, s, l */
1506 return 0;
1507 }
1508 /* take the tail entry */
1509 item = list_entry(trans->r_itemq.prev, xlog_recover_item_t, ri_list);
1510
1511 old_ptr = item->ri_buf[item->ri_cnt-1].i_addr;
1512 old_len = item->ri_buf[item->ri_cnt-1].i_len;
1513
1514 ptr = kmem_realloc(old_ptr, len+old_len, old_len, KM_SLEEP);
1515 memcpy(&ptr[old_len], dp, len); /* d, s, l */
1516 item->ri_buf[item->ri_cnt-1].i_len += len;
1517 item->ri_buf[item->ri_cnt-1].i_addr = ptr;
1518 trace_xfs_log_recover_item_add_cont(log, trans, item, 0);
1519 return 0;
1520}
1521
1522/*
1523 * The next region to add is the start of a new region. It could be
1524 * a whole region or it could be the first part of a new region. Because
1525 * of this, the assumption here is that the type and size fields of all
1526 * format structures fit into the first 32 bits of the structure.
1527 *
1528 * This works because all regions must be 32 bit aligned. Therefore, we
1529 * either have both fields or we have neither field. In the case we have
1530 * neither field, the data part of the region is zero length. We only have
1531 * a log_op_header and can throw away the header since a new one will appear
1532 * later. If we have at least 4 bytes, then we can determine how many regions
1533 * will appear in the current log item.
1534 */
1535STATIC int
1536xlog_recover_add_to_trans(
1537 struct xlog *log,
1538 struct xlog_recover *trans,
1539 xfs_caddr_t dp,
1540 int len)
1541{
1542 xfs_inode_log_format_t *in_f; /* any will do */
1543 xlog_recover_item_t *item;
1544 xfs_caddr_t ptr;
1545
1546 if (!len)
1547 return 0;
1548 if (list_empty(&trans->r_itemq)) {
1549 /* we need to catch log corruptions here */
1550 if (*(uint *)dp != XFS_TRANS_HEADER_MAGIC) {
1551 xfs_warn(log->l_mp, "%s: bad header magic number",
1552 __func__);
1553 ASSERT(0);
1554 return XFS_ERROR(EIO);
1555 }
1556 if (len == sizeof(xfs_trans_header_t))
1557 xlog_recover_add_item(&trans->r_itemq);
1558 memcpy(&trans->r_theader, dp, len); /* d, s, l */
1559 return 0;
1560 }
1561
1562 ptr = kmem_alloc(len, KM_SLEEP);
1563 memcpy(ptr, dp, len);
1564 in_f = (xfs_inode_log_format_t *)ptr;
1565
1566 /* take the tail entry */
1567 item = list_entry(trans->r_itemq.prev, xlog_recover_item_t, ri_list);
1568 if (item->ri_total != 0 &&
1569 item->ri_total == item->ri_cnt) {
1570 /* tail item is in use, get a new one */
1571 xlog_recover_add_item(&trans->r_itemq);
1572 item = list_entry(trans->r_itemq.prev,
1573 xlog_recover_item_t, ri_list);
1574 }
1575
1576 if (item->ri_total == 0) { /* first region to be added */
1577 if (in_f->ilf_size == 0 ||
1578 in_f->ilf_size > XLOG_MAX_REGIONS_IN_ITEM) {
1579 xfs_warn(log->l_mp,
1580 "bad number of regions (%d) in inode log format",
1581 in_f->ilf_size);
1582 ASSERT(0);
1583 kmem_free(ptr);
1584 return XFS_ERROR(EIO);
1585 }
1586
1587 item->ri_total = in_f->ilf_size;
1588 item->ri_buf =
1589 kmem_zalloc(item->ri_total * sizeof(xfs_log_iovec_t),
1590 KM_SLEEP);
1591 }
1592 ASSERT(item->ri_total > item->ri_cnt);
1593 /* Description region is ri_buf[0] */
1594 item->ri_buf[item->ri_cnt].i_addr = ptr;
1595 item->ri_buf[item->ri_cnt].i_len = len;
1596 item->ri_cnt++;
1597 trace_xfs_log_recover_item_add(log, trans, item, 0);
1598 return 0;
1599}
1600
1601/*
1602 * Sort the log items in the transaction.
1603 *
1604 * The ordering constraints are defined by the inode allocation and unlink
1605 * behaviour. The rules are:
1606 *
1607 * 1. Every item is only logged once in a given transaction. Hence it
1608 * represents the last logged state of the item. Hence ordering is
1609 * dependent on the order in which operations need to be performed so
1610 * required initial conditions are always met.
1611 *
1612 * 2. Cancelled buffers are recorded in pass 1 in a separate table and
1613 * there's nothing to replay from them so we can simply cull them
1614 * from the transaction. However, we can't do that until after we've
1615 * replayed all the other items because they may be dependent on the
1616 * cancelled buffer and replaying the cancelled buffer can remove it
1617 * form the cancelled buffer table. Hence they have tobe done last.
1618 *
1619 * 3. Inode allocation buffers must be replayed before inode items that
1620 * read the buffer and replay changes into it. For filesystems using the
1621 * ICREATE transactions, this means XFS_LI_ICREATE objects need to get
1622 * treated the same as inode allocation buffers as they create and
1623 * initialise the buffers directly.
1624 *
1625 * 4. Inode unlink buffers must be replayed after inode items are replayed.
1626 * This ensures that inodes are completely flushed to the inode buffer
1627 * in a "free" state before we remove the unlinked inode list pointer.
1628 *
1629 * Hence the ordering needs to be inode allocation buffers first, inode items
1630 * second, inode unlink buffers third and cancelled buffers last.
1631 *
1632 * But there's a problem with that - we can't tell an inode allocation buffer
1633 * apart from a regular buffer, so we can't separate them. We can, however,
1634 * tell an inode unlink buffer from the others, and so we can separate them out
1635 * from all the other buffers and move them to last.
1636 *
1637 * Hence, 4 lists, in order from head to tail:
1638 * - buffer_list for all buffers except cancelled/inode unlink buffers
1639 * - item_list for all non-buffer items
1640 * - inode_buffer_list for inode unlink buffers
1641 * - cancel_list for the cancelled buffers
1642 *
1643 * Note that we add objects to the tail of the lists so that first-to-last
1644 * ordering is preserved within the lists. Adding objects to the head of the
1645 * list means when we traverse from the head we walk them in last-to-first
1646 * order. For cancelled buffers and inode unlink buffers this doesn't matter,
1647 * but for all other items there may be specific ordering that we need to
1648 * preserve.
1649 */
1650STATIC int
1651xlog_recover_reorder_trans(
1652 struct xlog *log,
1653 struct xlog_recover *trans,
1654 int pass)
1655{
1656 xlog_recover_item_t *item, *n;
1657 int error = 0;
1658 LIST_HEAD(sort_list);
1659 LIST_HEAD(cancel_list);
1660 LIST_HEAD(buffer_list);
1661 LIST_HEAD(inode_buffer_list);
1662 LIST_HEAD(inode_list);
1663
1664 list_splice_init(&trans->r_itemq, &sort_list);
1665 list_for_each_entry_safe(item, n, &sort_list, ri_list) {
1666 xfs_buf_log_format_t *buf_f = item->ri_buf[0].i_addr;
1667
1668 switch (ITEM_TYPE(item)) {
1669 case XFS_LI_ICREATE:
1670 list_move_tail(&item->ri_list, &buffer_list);
1671 break;
1672 case XFS_LI_BUF:
1673 if (buf_f->blf_flags & XFS_BLF_CANCEL) {
1674 trace_xfs_log_recover_item_reorder_head(log,
1675 trans, item, pass);
1676 list_move(&item->ri_list, &cancel_list);
1677 break;
1678 }
1679 if (buf_f->blf_flags & XFS_BLF_INODE_BUF) {
1680 list_move(&item->ri_list, &inode_buffer_list);
1681 break;
1682 }
1683 list_move_tail(&item->ri_list, &buffer_list);
1684 break;
1685 case XFS_LI_INODE:
1686 case XFS_LI_DQUOT:
1687 case XFS_LI_QUOTAOFF:
1688 case XFS_LI_EFD:
1689 case XFS_LI_EFI:
1690 trace_xfs_log_recover_item_reorder_tail(log,
1691 trans, item, pass);
1692 list_move_tail(&item->ri_list, &inode_list);
1693 break;
1694 default:
1695 xfs_warn(log->l_mp,
1696 "%s: unrecognized type of log operation",
1697 __func__);
1698 ASSERT(0);
1699 /*
1700 * return the remaining items back to the transaction
1701 * item list so they can be freed in caller.
1702 */
1703 if (!list_empty(&sort_list))
1704 list_splice_init(&sort_list, &trans->r_itemq);
1705 error = XFS_ERROR(EIO);
1706 goto out;
1707 }
1708 }
1709out:
1710 ASSERT(list_empty(&sort_list));
1711 if (!list_empty(&buffer_list))
1712 list_splice(&buffer_list, &trans->r_itemq);
1713 if (!list_empty(&inode_list))
1714 list_splice_tail(&inode_list, &trans->r_itemq);
1715 if (!list_empty(&inode_buffer_list))
1716 list_splice_tail(&inode_buffer_list, &trans->r_itemq);
1717 if (!list_empty(&cancel_list))
1718 list_splice_tail(&cancel_list, &trans->r_itemq);
1719 return error;
1720}
1721
1722/*
1723 * Build up the table of buf cancel records so that we don't replay
1724 * cancelled data in the second pass. For buffer records that are
1725 * not cancel records, there is nothing to do here so we just return.
1726 *
1727 * If we get a cancel record which is already in the table, this indicates
1728 * that the buffer was cancelled multiple times. In order to ensure
1729 * that during pass 2 we keep the record in the table until we reach its
1730 * last occurrence in the log, we keep a reference count in the cancel
1731 * record in the table to tell us how many times we expect to see this
1732 * record during the second pass.
1733 */
1734STATIC int
1735xlog_recover_buffer_pass1(
1736 struct xlog *log,
1737 struct xlog_recover_item *item)
1738{
1739 xfs_buf_log_format_t *buf_f = item->ri_buf[0].i_addr;
1740 struct list_head *bucket;
1741 struct xfs_buf_cancel *bcp;
1742
1743 /*
1744 * If this isn't a cancel buffer item, then just return.
1745 */
1746 if (!(buf_f->blf_flags & XFS_BLF_CANCEL)) {
1747 trace_xfs_log_recover_buf_not_cancel(log, buf_f);
1748 return 0;
1749 }
1750
1751 /*
1752 * Insert an xfs_buf_cancel record into the hash table of them.
1753 * If there is already an identical record, bump its reference count.
1754 */
1755 bucket = XLOG_BUF_CANCEL_BUCKET(log, buf_f->blf_blkno);
1756 list_for_each_entry(bcp, bucket, bc_list) {
1757 if (bcp->bc_blkno == buf_f->blf_blkno &&
1758 bcp->bc_len == buf_f->blf_len) {
1759 bcp->bc_refcount++;
1760 trace_xfs_log_recover_buf_cancel_ref_inc(log, buf_f);
1761 return 0;
1762 }
1763 }
1764
1765 bcp = kmem_alloc(sizeof(struct xfs_buf_cancel), KM_SLEEP);
1766 bcp->bc_blkno = buf_f->blf_blkno;
1767 bcp->bc_len = buf_f->blf_len;
1768 bcp->bc_refcount = 1;
1769 list_add_tail(&bcp->bc_list, bucket);
1770
1771 trace_xfs_log_recover_buf_cancel_add(log, buf_f);
1772 return 0;
1773}
1774
1775/*
1776 * Check to see whether the buffer being recovered has a corresponding
1777 * entry in the buffer cancel record table. If it is, return the cancel
1778 * buffer structure to the caller.
1779 */
1780STATIC struct xfs_buf_cancel *
1781xlog_peek_buffer_cancelled(
1782 struct xlog *log,
1783 xfs_daddr_t blkno,
1784 uint len,
1785 ushort flags)
1786{
1787 struct list_head *bucket;
1788 struct xfs_buf_cancel *bcp;
1789
1790 if (!log->l_buf_cancel_table) {
1791 /* empty table means no cancelled buffers in the log */
1792 ASSERT(!(flags & XFS_BLF_CANCEL));
1793 return NULL;
1794 }
1795
1796 bucket = XLOG_BUF_CANCEL_BUCKET(log, blkno);
1797 list_for_each_entry(bcp, bucket, bc_list) {
1798 if (bcp->bc_blkno == blkno && bcp->bc_len == len)
1799 return bcp;
1800 }
1801
1802 /*
1803 * We didn't find a corresponding entry in the table, so return 0 so
1804 * that the buffer is NOT cancelled.
1805 */
1806 ASSERT(!(flags & XFS_BLF_CANCEL));
1807 return NULL;
1808}
1809
1810/*
1811 * If the buffer is being cancelled then return 1 so that it will be cancelled,
1812 * otherwise return 0. If the buffer is actually a buffer cancel item
1813 * (XFS_BLF_CANCEL is set), then decrement the refcount on the entry in the
1814 * table and remove it from the table if this is the last reference.
1815 *
1816 * We remove the cancel record from the table when we encounter its last
1817 * occurrence in the log so that if the same buffer is re-used again after its
1818 * last cancellation we actually replay the changes made at that point.
1819 */
1820STATIC int
1821xlog_check_buffer_cancelled(
1822 struct xlog *log,
1823 xfs_daddr_t blkno,
1824 uint len,
1825 ushort flags)
1826{
1827 struct xfs_buf_cancel *bcp;
1828
1829 bcp = xlog_peek_buffer_cancelled(log, blkno, len, flags);
1830 if (!bcp)
1831 return 0;
1832
1833 /*
1834 * We've go a match, so return 1 so that the recovery of this buffer
1835 * is cancelled. If this buffer is actually a buffer cancel log
1836 * item, then decrement the refcount on the one in the table and
1837 * remove it if this is the last reference.
1838 */
1839 if (flags & XFS_BLF_CANCEL) {
1840 if (--bcp->bc_refcount == 0) {
1841 list_del(&bcp->bc_list);
1842 kmem_free(bcp);
1843 }
1844 }
1845 return 1;
1846}
1847
1848/*
1849 * Perform recovery for a buffer full of inodes. In these buffers, the only
1850 * data which should be recovered is that which corresponds to the
1851 * di_next_unlinked pointers in the on disk inode structures. The rest of the
1852 * data for the inodes is always logged through the inodes themselves rather
1853 * than the inode buffer and is recovered in xlog_recover_inode_pass2().
1854 *
1855 * The only time when buffers full of inodes are fully recovered is when the
1856 * buffer is full of newly allocated inodes. In this case the buffer will
1857 * not be marked as an inode buffer and so will be sent to
1858 * xlog_recover_do_reg_buffer() below during recovery.
1859 */
1860STATIC int
1861xlog_recover_do_inode_buffer(
1862 struct xfs_mount *mp,
1863 xlog_recover_item_t *item,
1864 struct xfs_buf *bp,
1865 xfs_buf_log_format_t *buf_f)
1866{
1867 int i;
1868 int item_index = 0;
1869 int bit = 0;
1870 int nbits = 0;
1871 int reg_buf_offset = 0;
1872 int reg_buf_bytes = 0;
1873 int next_unlinked_offset;
1874 int inodes_per_buf;
1875 xfs_agino_t *logged_nextp;
1876 xfs_agino_t *buffer_nextp;
1877
1878 trace_xfs_log_recover_buf_inode_buf(mp->m_log, buf_f);
1879
1880 /*
1881 * Post recovery validation only works properly on CRC enabled
1882 * filesystems.
1883 */
1884 if (xfs_sb_version_hascrc(&mp->m_sb))
1885 bp->b_ops = &xfs_inode_buf_ops;
1886
1887 inodes_per_buf = BBTOB(bp->b_io_length) >> mp->m_sb.sb_inodelog;
1888 for (i = 0; i < inodes_per_buf; i++) {
1889 next_unlinked_offset = (i * mp->m_sb.sb_inodesize) +
1890 offsetof(xfs_dinode_t, di_next_unlinked);
1891
1892 while (next_unlinked_offset >=
1893 (reg_buf_offset + reg_buf_bytes)) {
1894 /*
1895 * The next di_next_unlinked field is beyond
1896 * the current logged region. Find the next
1897 * logged region that contains or is beyond
1898 * the current di_next_unlinked field.
1899 */
1900 bit += nbits;
1901 bit = xfs_next_bit(buf_f->blf_data_map,
1902 buf_f->blf_map_size, bit);
1903
1904 /*
1905 * If there are no more logged regions in the
1906 * buffer, then we're done.
1907 */
1908 if (bit == -1)
1909 return 0;
1910
1911 nbits = xfs_contig_bits(buf_f->blf_data_map,
1912 buf_f->blf_map_size, bit);
1913 ASSERT(nbits > 0);
1914 reg_buf_offset = bit << XFS_BLF_SHIFT;
1915 reg_buf_bytes = nbits << XFS_BLF_SHIFT;
1916 item_index++;
1917 }
1918
1919 /*
1920 * If the current logged region starts after the current
1921 * di_next_unlinked field, then move on to the next
1922 * di_next_unlinked field.
1923 */
1924 if (next_unlinked_offset < reg_buf_offset)
1925 continue;
1926
1927 ASSERT(item->ri_buf[item_index].i_addr != NULL);
1928 ASSERT((item->ri_buf[item_index].i_len % XFS_BLF_CHUNK) == 0);
1929 ASSERT((reg_buf_offset + reg_buf_bytes) <=
1930 BBTOB(bp->b_io_length));
1931
1932 /*
1933 * The current logged region contains a copy of the
1934 * current di_next_unlinked field. Extract its value
1935 * and copy it to the buffer copy.
1936 */
1937 logged_nextp = item->ri_buf[item_index].i_addr +
1938 next_unlinked_offset - reg_buf_offset;
1939 if (unlikely(*logged_nextp == 0)) {
1940 xfs_alert(mp,
1941 "Bad inode buffer log record (ptr = 0x%p, bp = 0x%p). "
1942 "Trying to replay bad (0) inode di_next_unlinked field.",
1943 item, bp);
1944 XFS_ERROR_REPORT("xlog_recover_do_inode_buf",
1945 XFS_ERRLEVEL_LOW, mp);
1946 return XFS_ERROR(EFSCORRUPTED);
1947 }
1948
1949 buffer_nextp = (xfs_agino_t *)xfs_buf_offset(bp,
1950 next_unlinked_offset);
1951 *buffer_nextp = *logged_nextp;
1952
1953 /*
1954 * If necessary, recalculate the CRC in the on-disk inode. We
1955 * have to leave the inode in a consistent state for whoever
1956 * reads it next....
1957 */
1958 xfs_dinode_calc_crc(mp, (struct xfs_dinode *)
1959 xfs_buf_offset(bp, i * mp->m_sb.sb_inodesize));
1960
1961 }
1962
1963 return 0;
1964}
1965
1966/*
1967 * V5 filesystems know the age of the buffer on disk being recovered. We can
1968 * have newer objects on disk than we are replaying, and so for these cases we
1969 * don't want to replay the current change as that will make the buffer contents
1970 * temporarily invalid on disk.
1971 *
1972 * The magic number might not match the buffer type we are going to recover
1973 * (e.g. reallocated blocks), so we ignore the xfs_buf_log_format flags. Hence
1974 * extract the LSN of the existing object in the buffer based on it's current
1975 * magic number. If we don't recognise the magic number in the buffer, then
1976 * return a LSN of -1 so that the caller knows it was an unrecognised block and
1977 * so can recover the buffer.
1978 *
1979 * Note: we cannot rely solely on magic number matches to determine that the
1980 * buffer has a valid LSN - we also need to verify that it belongs to this
1981 * filesystem, so we need to extract the object's LSN and compare it to that
1982 * which we read from the superblock. If the UUIDs don't match, then we've got a
1983 * stale metadata block from an old filesystem instance that we need to recover
1984 * over the top of.
1985 */
1986static xfs_lsn_t
1987xlog_recover_get_buf_lsn(
1988 struct xfs_mount *mp,
1989 struct xfs_buf *bp)
1990{
1991 __uint32_t magic32;
1992 __uint16_t magic16;
1993 __uint16_t magicda;
1994 void *blk = bp->b_addr;
1995 uuid_t *uuid;
1996 xfs_lsn_t lsn = -1;
1997
1998 /* v4 filesystems always recover immediately */
1999 if (!xfs_sb_version_hascrc(&mp->m_sb))
2000 goto recover_immediately;
2001
2002 magic32 = be32_to_cpu(*(__be32 *)blk);
2003 switch (magic32) {
2004 case XFS_ABTB_CRC_MAGIC:
2005 case XFS_ABTC_CRC_MAGIC:
2006 case XFS_ABTB_MAGIC:
2007 case XFS_ABTC_MAGIC:
2008 case XFS_IBT_CRC_MAGIC:
2009 case XFS_IBT_MAGIC: {
2010 struct xfs_btree_block *btb = blk;
2011
2012 lsn = be64_to_cpu(btb->bb_u.s.bb_lsn);
2013 uuid = &btb->bb_u.s.bb_uuid;
2014 break;
2015 }
2016 case XFS_BMAP_CRC_MAGIC:
2017 case XFS_BMAP_MAGIC: {
2018 struct xfs_btree_block *btb = blk;
2019
2020 lsn = be64_to_cpu(btb->bb_u.l.bb_lsn);
2021 uuid = &btb->bb_u.l.bb_uuid;
2022 break;
2023 }
2024 case XFS_AGF_MAGIC:
2025 lsn = be64_to_cpu(((struct xfs_agf *)blk)->agf_lsn);
2026 uuid = &((struct xfs_agf *)blk)->agf_uuid;
2027 break;
2028 case XFS_AGFL_MAGIC:
2029 lsn = be64_to_cpu(((struct xfs_agfl *)blk)->agfl_lsn);
2030 uuid = &((struct xfs_agfl *)blk)->agfl_uuid;
2031 break;
2032 case XFS_AGI_MAGIC:
2033 lsn = be64_to_cpu(((struct xfs_agi *)blk)->agi_lsn);
2034 uuid = &((struct xfs_agi *)blk)->agi_uuid;
2035 break;
2036 case XFS_SYMLINK_MAGIC:
2037 lsn = be64_to_cpu(((struct xfs_dsymlink_hdr *)blk)->sl_lsn);
2038 uuid = &((struct xfs_dsymlink_hdr *)blk)->sl_uuid;
2039 break;
2040 case XFS_DIR3_BLOCK_MAGIC:
2041 case XFS_DIR3_DATA_MAGIC:
2042 case XFS_DIR3_FREE_MAGIC:
2043 lsn = be64_to_cpu(((struct xfs_dir3_blk_hdr *)blk)->lsn);
2044 uuid = &((struct xfs_dir3_blk_hdr *)blk)->uuid;
2045 break;
2046 case XFS_ATTR3_RMT_MAGIC:
2047 lsn = be64_to_cpu(((struct xfs_attr3_rmt_hdr *)blk)->rm_lsn);
2048 uuid = &((struct xfs_attr3_rmt_hdr *)blk)->rm_uuid;
2049 break;
2050 case XFS_SB_MAGIC:
2051 lsn = be64_to_cpu(((struct xfs_dsb *)blk)->sb_lsn);
2052 uuid = &((struct xfs_dsb *)blk)->sb_uuid;
2053 break;
2054 default:
2055 break;
2056 }
2057
2058 if (lsn != (xfs_lsn_t)-1) {
2059 if (!uuid_equal(&mp->m_sb.sb_uuid, uuid))
2060 goto recover_immediately;
2061 return lsn;
2062 }
2063
2064 magicda = be16_to_cpu(((struct xfs_da_blkinfo *)blk)->magic);
2065 switch (magicda) {
2066 case XFS_DIR3_LEAF1_MAGIC:
2067 case XFS_DIR3_LEAFN_MAGIC:
2068 case XFS_DA3_NODE_MAGIC:
2069 lsn = be64_to_cpu(((struct xfs_da3_blkinfo *)blk)->lsn);
2070 uuid = &((struct xfs_da3_blkinfo *)blk)->uuid;
2071 break;
2072 default:
2073 break;
2074 }
2075
2076 if (lsn != (xfs_lsn_t)-1) {
2077 if (!uuid_equal(&mp->m_sb.sb_uuid, uuid))
2078 goto recover_immediately;
2079 return lsn;
2080 }
2081
2082 /*
2083 * We do individual object checks on dquot and inode buffers as they
2084 * have their own individual LSN records. Also, we could have a stale
2085 * buffer here, so we have to at least recognise these buffer types.
2086 *
2087 * A notd complexity here is inode unlinked list processing - it logs
2088 * the inode directly in the buffer, but we don't know which inodes have
2089 * been modified, and there is no global buffer LSN. Hence we need to
2090 * recover all inode buffer types immediately. This problem will be
2091 * fixed by logical logging of the unlinked list modifications.
2092 */
2093 magic16 = be16_to_cpu(*(__be16 *)blk);
2094 switch (magic16) {
2095 case XFS_DQUOT_MAGIC:
2096 case XFS_DINODE_MAGIC:
2097 goto recover_immediately;
2098 default:
2099 break;
2100 }
2101
2102 /* unknown buffer contents, recover immediately */
2103
2104recover_immediately:
2105 return (xfs_lsn_t)-1;
2106
2107}
2108
2109/*
2110 * Validate the recovered buffer is of the correct type and attach the
2111 * appropriate buffer operations to them for writeback. Magic numbers are in a
2112 * few places:
2113 * the first 16 bits of the buffer (inode buffer, dquot buffer),
2114 * the first 32 bits of the buffer (most blocks),
2115 * inside a struct xfs_da_blkinfo at the start of the buffer.
2116 */
2117static void
2118xlog_recover_validate_buf_type(
2119 struct xfs_mount *mp,
2120 struct xfs_buf *bp,
2121 xfs_buf_log_format_t *buf_f)
2122{
2123 struct xfs_da_blkinfo *info = bp->b_addr;
2124 __uint32_t magic32;
2125 __uint16_t magic16;
2126 __uint16_t magicda;
2127
2128 magic32 = be32_to_cpu(*(__be32 *)bp->b_addr);
2129 magic16 = be16_to_cpu(*(__be16*)bp->b_addr);
2130 magicda = be16_to_cpu(info->magic);
2131 switch (xfs_blft_from_flags(buf_f)) {
2132 case XFS_BLFT_BTREE_BUF:
2133 switch (magic32) {
2134 case XFS_ABTB_CRC_MAGIC:
2135 case XFS_ABTC_CRC_MAGIC:
2136 case XFS_ABTB_MAGIC:
2137 case XFS_ABTC_MAGIC:
2138 bp->b_ops = &xfs_allocbt_buf_ops;
2139 break;
2140 case XFS_IBT_CRC_MAGIC:
2141 case XFS_IBT_MAGIC:
2142 bp->b_ops = &xfs_inobt_buf_ops;
2143 break;
2144 case XFS_BMAP_CRC_MAGIC:
2145 case XFS_BMAP_MAGIC:
2146 bp->b_ops = &xfs_bmbt_buf_ops;
2147 break;
2148 default:
2149 xfs_warn(mp, "Bad btree block magic!");
2150 ASSERT(0);
2151 break;
2152 }
2153 break;
2154 case XFS_BLFT_AGF_BUF:
2155 if (magic32 != XFS_AGF_MAGIC) {
2156 xfs_warn(mp, "Bad AGF block magic!");
2157 ASSERT(0);
2158 break;
2159 }
2160 bp->b_ops = &xfs_agf_buf_ops;
2161 break;
2162 case XFS_BLFT_AGFL_BUF:
2163 if (!xfs_sb_version_hascrc(&mp->m_sb))
2164 break;
2165 if (magic32 != XFS_AGFL_MAGIC) {
2166 xfs_warn(mp, "Bad AGFL block magic!");
2167 ASSERT(0);
2168 break;
2169 }
2170 bp->b_ops = &xfs_agfl_buf_ops;
2171 break;
2172 case XFS_BLFT_AGI_BUF:
2173 if (magic32 != XFS_AGI_MAGIC) {
2174 xfs_warn(mp, "Bad AGI block magic!");
2175 ASSERT(0);
2176 break;
2177 }
2178 bp->b_ops = &xfs_agi_buf_ops;
2179 break;
2180 case XFS_BLFT_UDQUOT_BUF:
2181 case XFS_BLFT_PDQUOT_BUF:
2182 case XFS_BLFT_GDQUOT_BUF:
2183#ifdef CONFIG_XFS_QUOTA
2184 if (magic16 != XFS_DQUOT_MAGIC) {
2185 xfs_warn(mp, "Bad DQUOT block magic!");
2186 ASSERT(0);
2187 break;
2188 }
2189 bp->b_ops = &xfs_dquot_buf_ops;
2190#else
2191 xfs_alert(mp,
2192 "Trying to recover dquots without QUOTA support built in!");
2193 ASSERT(0);
2194#endif
2195 break;
2196 case XFS_BLFT_DINO_BUF:
2197 /*
2198 * we get here with inode allocation buffers, not buffers that
2199 * track unlinked list changes.
2200 */
2201 if (magic16 != XFS_DINODE_MAGIC) {
2202 xfs_warn(mp, "Bad INODE block magic!");
2203 ASSERT(0);
2204 break;
2205 }
2206 bp->b_ops = &xfs_inode_buf_ops;
2207 break;
2208 case XFS_BLFT_SYMLINK_BUF:
2209 if (magic32 != XFS_SYMLINK_MAGIC) {
2210 xfs_warn(mp, "Bad symlink block magic!");
2211 ASSERT(0);
2212 break;
2213 }
2214 bp->b_ops = &xfs_symlink_buf_ops;
2215 break;
2216 case XFS_BLFT_DIR_BLOCK_BUF:
2217 if (magic32 != XFS_DIR2_BLOCK_MAGIC &&
2218 magic32 != XFS_DIR3_BLOCK_MAGIC) {
2219 xfs_warn(mp, "Bad dir block magic!");
2220 ASSERT(0);
2221 break;
2222 }
2223 bp->b_ops = &xfs_dir3_block_buf_ops;
2224 break;
2225 case XFS_BLFT_DIR_DATA_BUF:
2226 if (magic32 != XFS_DIR2_DATA_MAGIC &&
2227 magic32 != XFS_DIR3_DATA_MAGIC) {
2228 xfs_warn(mp, "Bad dir data magic!");
2229 ASSERT(0);
2230 break;
2231 }
2232 bp->b_ops = &xfs_dir3_data_buf_ops;
2233 break;
2234 case XFS_BLFT_DIR_FREE_BUF:
2235 if (magic32 != XFS_DIR2_FREE_MAGIC &&
2236 magic32 != XFS_DIR3_FREE_MAGIC) {
2237 xfs_warn(mp, "Bad dir3 free magic!");
2238 ASSERT(0);
2239 break;
2240 }
2241 bp->b_ops = &xfs_dir3_free_buf_ops;
2242 break;
2243 case XFS_BLFT_DIR_LEAF1_BUF:
2244 if (magicda != XFS_DIR2_LEAF1_MAGIC &&
2245 magicda != XFS_DIR3_LEAF1_MAGIC) {
2246 xfs_warn(mp, "Bad dir leaf1 magic!");
2247 ASSERT(0);
2248 break;
2249 }
2250 bp->b_ops = &xfs_dir3_leaf1_buf_ops;
2251 break;
2252 case XFS_BLFT_DIR_LEAFN_BUF:
2253 if (magicda != XFS_DIR2_LEAFN_MAGIC &&
2254 magicda != XFS_DIR3_LEAFN_MAGIC) {
2255 xfs_warn(mp, "Bad dir leafn magic!");
2256 ASSERT(0);
2257 break;
2258 }
2259 bp->b_ops = &xfs_dir3_leafn_buf_ops;
2260 break;
2261 case XFS_BLFT_DA_NODE_BUF:
2262 if (magicda != XFS_DA_NODE_MAGIC &&
2263 magicda != XFS_DA3_NODE_MAGIC) {
2264 xfs_warn(mp, "Bad da node magic!");
2265 ASSERT(0);
2266 break;
2267 }
2268 bp->b_ops = &xfs_da3_node_buf_ops;
2269 break;
2270 case XFS_BLFT_ATTR_LEAF_BUF:
2271 if (magicda != XFS_ATTR_LEAF_MAGIC &&
2272 magicda != XFS_ATTR3_LEAF_MAGIC) {
2273 xfs_warn(mp, "Bad attr leaf magic!");
2274 ASSERT(0);
2275 break;
2276 }
2277 bp->b_ops = &xfs_attr3_leaf_buf_ops;
2278 break;
2279 case XFS_BLFT_ATTR_RMT_BUF:
2280 if (!xfs_sb_version_hascrc(&mp->m_sb))
2281 break;
2282 if (magic32 != XFS_ATTR3_RMT_MAGIC) {
2283 xfs_warn(mp, "Bad attr remote magic!");
2284 ASSERT(0);
2285 break;
2286 }
2287 bp->b_ops = &xfs_attr3_rmt_buf_ops;
2288 break;
2289 case XFS_BLFT_SB_BUF:
2290 if (magic32 != XFS_SB_MAGIC) {
2291 xfs_warn(mp, "Bad SB block magic!");
2292 ASSERT(0);
2293 break;
2294 }
2295 bp->b_ops = &xfs_sb_buf_ops;
2296 break;
2297 default:
2298 xfs_warn(mp, "Unknown buffer type %d!",
2299 xfs_blft_from_flags(buf_f));
2300 break;
2301 }
2302}
2303
2304/*
2305 * Perform a 'normal' buffer recovery. Each logged region of the
2306 * buffer should be copied over the corresponding region in the
2307 * given buffer. The bitmap in the buf log format structure indicates
2308 * where to place the logged data.
2309 */
2310STATIC void
2311xlog_recover_do_reg_buffer(
2312 struct xfs_mount *mp,
2313 xlog_recover_item_t *item,
2314 struct xfs_buf *bp,
2315 xfs_buf_log_format_t *buf_f)
2316{
2317 int i;
2318 int bit;
2319 int nbits;
2320 int error;
2321
2322 trace_xfs_log_recover_buf_reg_buf(mp->m_log, buf_f);
2323
2324 bit = 0;
2325 i = 1; /* 0 is the buf format structure */
2326 while (1) {
2327 bit = xfs_next_bit(buf_f->blf_data_map,
2328 buf_f->blf_map_size, bit);
2329 if (bit == -1)
2330 break;
2331 nbits = xfs_contig_bits(buf_f->blf_data_map,
2332 buf_f->blf_map_size, bit);
2333 ASSERT(nbits > 0);
2334 ASSERT(item->ri_buf[i].i_addr != NULL);
2335 ASSERT(item->ri_buf[i].i_len % XFS_BLF_CHUNK == 0);
2336 ASSERT(BBTOB(bp->b_io_length) >=
2337 ((uint)bit << XFS_BLF_SHIFT) + (nbits << XFS_BLF_SHIFT));
2338
2339 /*
2340 * The dirty regions logged in the buffer, even though
2341 * contiguous, may span multiple chunks. This is because the
2342 * dirty region may span a physical page boundary in a buffer
2343 * and hence be split into two separate vectors for writing into
2344 * the log. Hence we need to trim nbits back to the length of
2345 * the current region being copied out of the log.
2346 */
2347 if (item->ri_buf[i].i_len < (nbits << XFS_BLF_SHIFT))
2348 nbits = item->ri_buf[i].i_len >> XFS_BLF_SHIFT;
2349
2350 /*
2351 * Do a sanity check if this is a dquot buffer. Just checking
2352 * the first dquot in the buffer should do. XXXThis is
2353 * probably a good thing to do for other buf types also.
2354 */
2355 error = 0;
2356 if (buf_f->blf_flags &
2357 (XFS_BLF_UDQUOT_BUF|XFS_BLF_PDQUOT_BUF|XFS_BLF_GDQUOT_BUF)) {
2358 if (item->ri_buf[i].i_addr == NULL) {
2359 xfs_alert(mp,
2360 "XFS: NULL dquot in %s.", __func__);
2361 goto next;
2362 }
2363 if (item->ri_buf[i].i_len < sizeof(xfs_disk_dquot_t)) {
2364 xfs_alert(mp,
2365 "XFS: dquot too small (%d) in %s.",
2366 item->ri_buf[i].i_len, __func__);
2367 goto next;
2368 }
2369 error = xfs_dqcheck(mp, item->ri_buf[i].i_addr,
2370 -1, 0, XFS_QMOPT_DOWARN,
2371 "dquot_buf_recover");
2372 if (error)
2373 goto next;
2374 }
2375
2376 memcpy(xfs_buf_offset(bp,
2377 (uint)bit << XFS_BLF_SHIFT), /* dest */
2378 item->ri_buf[i].i_addr, /* source */
2379 nbits<<XFS_BLF_SHIFT); /* length */
2380 next:
2381 i++;
2382 bit += nbits;
2383 }
2384
2385 /* Shouldn't be any more regions */
2386 ASSERT(i == item->ri_total);
2387
2388 /*
2389 * We can only do post recovery validation on items on CRC enabled
2390 * fielsystems as we need to know when the buffer was written to be able
2391 * to determine if we should have replayed the item. If we replay old
2392 * metadata over a newer buffer, then it will enter a temporarily
2393 * inconsistent state resulting in verification failures. Hence for now
2394 * just avoid the verification stage for non-crc filesystems
2395 */
2396 if (xfs_sb_version_hascrc(&mp->m_sb))
2397 xlog_recover_validate_buf_type(mp, bp, buf_f);
2398}
2399
2400/*
2401 * Perform a dquot buffer recovery.
2402 * Simple algorithm: if we have found a QUOTAOFF log item of the same type
2403 * (ie. USR or GRP), then just toss this buffer away; don't recover it.
2404 * Else, treat it as a regular buffer and do recovery.
2405 */
2406STATIC void
2407xlog_recover_do_dquot_buffer(
2408 struct xfs_mount *mp,
2409 struct xlog *log,
2410 struct xlog_recover_item *item,
2411 struct xfs_buf *bp,
2412 struct xfs_buf_log_format *buf_f)
2413{
2414 uint type;
2415
2416 trace_xfs_log_recover_buf_dquot_buf(log, buf_f);
2417
2418 /*
2419 * Filesystems are required to send in quota flags at mount time.
2420 */
2421 if (mp->m_qflags == 0) {
2422 return;
2423 }
2424
2425 type = 0;
2426 if (buf_f->blf_flags & XFS_BLF_UDQUOT_BUF)
2427 type |= XFS_DQ_USER;
2428 if (buf_f->blf_flags & XFS_BLF_PDQUOT_BUF)
2429 type |= XFS_DQ_PROJ;
2430 if (buf_f->blf_flags & XFS_BLF_GDQUOT_BUF)
2431 type |= XFS_DQ_GROUP;
2432 /*
2433 * This type of quotas was turned off, so ignore this buffer
2434 */
2435 if (log->l_quotaoffs_flag & type)
2436 return;
2437
2438 xlog_recover_do_reg_buffer(mp, item, bp, buf_f);
2439}
2440
2441/*
2442 * This routine replays a modification made to a buffer at runtime.
2443 * There are actually two types of buffer, regular and inode, which
2444 * are handled differently. Inode buffers are handled differently
2445 * in that we only recover a specific set of data from them, namely
2446 * the inode di_next_unlinked fields. This is because all other inode
2447 * data is actually logged via inode records and any data we replay
2448 * here which overlaps that may be stale.
2449 *
2450 * When meta-data buffers are freed at run time we log a buffer item
2451 * with the XFS_BLF_CANCEL bit set to indicate that previous copies
2452 * of the buffer in the log should not be replayed at recovery time.
2453 * This is so that if the blocks covered by the buffer are reused for
2454 * file data before we crash we don't end up replaying old, freed
2455 * meta-data into a user's file.
2456 *
2457 * To handle the cancellation of buffer log items, we make two passes
2458 * over the log during recovery. During the first we build a table of
2459 * those buffers which have been cancelled, and during the second we
2460 * only replay those buffers which do not have corresponding cancel
2461 * records in the table. See xlog_recover_buffer_pass[1,2] above
2462 * for more details on the implementation of the table of cancel records.
2463 */
2464STATIC int
2465xlog_recover_buffer_pass2(
2466 struct xlog *log,
2467 struct list_head *buffer_list,
2468 struct xlog_recover_item *item,
2469 xfs_lsn_t current_lsn)
2470{
2471 xfs_buf_log_format_t *buf_f = item->ri_buf[0].i_addr;
2472 xfs_mount_t *mp = log->l_mp;
2473 xfs_buf_t *bp;
2474 int error;
2475 uint buf_flags;
2476 xfs_lsn_t lsn;
2477
2478 /*
2479 * In this pass we only want to recover all the buffers which have
2480 * not been cancelled and are not cancellation buffers themselves.
2481 */
2482 if (xlog_check_buffer_cancelled(log, buf_f->blf_blkno,
2483 buf_f->blf_len, buf_f->blf_flags)) {
2484 trace_xfs_log_recover_buf_cancel(log, buf_f);
2485 return 0;
2486 }
2487
2488 trace_xfs_log_recover_buf_recover(log, buf_f);
2489
2490 buf_flags = 0;
2491 if (buf_f->blf_flags & XFS_BLF_INODE_BUF)
2492 buf_flags |= XBF_UNMAPPED;
2493
2494 bp = xfs_buf_read(mp->m_ddev_targp, buf_f->blf_blkno, buf_f->blf_len,
2495 buf_flags, NULL);
2496 if (!bp)
2497 return XFS_ERROR(ENOMEM);
2498 error = bp->b_error;
2499 if (error) {
2500 xfs_buf_ioerror_alert(bp, "xlog_recover_do..(read#1)");
2501 goto out_release;
2502 }
2503
2504 /*
2505 * recover the buffer only if we get an LSN from it and it's less than
2506 * the lsn of the transaction we are replaying.
2507 */
2508 lsn = xlog_recover_get_buf_lsn(mp, bp);
2509 if (lsn && lsn != -1 && XFS_LSN_CMP(lsn, current_lsn) >= 0)
2510 goto out_release;
2511
2512 if (buf_f->blf_flags & XFS_BLF_INODE_BUF) {
2513 error = xlog_recover_do_inode_buffer(mp, item, bp, buf_f);
2514 } else if (buf_f->blf_flags &
2515 (XFS_BLF_UDQUOT_BUF|XFS_BLF_PDQUOT_BUF|XFS_BLF_GDQUOT_BUF)) {
2516 xlog_recover_do_dquot_buffer(mp, log, item, bp, buf_f);
2517 } else {
2518 xlog_recover_do_reg_buffer(mp, item, bp, buf_f);
2519 }
2520 if (error)
2521 goto out_release;
2522
2523 /*
2524 * Perform delayed write on the buffer. Asynchronous writes will be
2525 * slower when taking into account all the buffers to be flushed.
2526 *
2527 * Also make sure that only inode buffers with good sizes stay in
2528 * the buffer cache. The kernel moves inodes in buffers of 1 block
2529 * or mp->m_inode_cluster_size bytes, whichever is bigger. The inode
2530 * buffers in the log can be a different size if the log was generated
2531 * by an older kernel using unclustered inode buffers or a newer kernel
2532 * running with a different inode cluster size. Regardless, if the
2533 * the inode buffer size isn't MAX(blocksize, mp->m_inode_cluster_size)
2534 * for *our* value of mp->m_inode_cluster_size, then we need to keep
2535 * the buffer out of the buffer cache so that the buffer won't
2536 * overlap with future reads of those inodes.
2537 */
2538 if (XFS_DINODE_MAGIC ==
2539 be16_to_cpu(*((__be16 *)xfs_buf_offset(bp, 0))) &&
2540 (BBTOB(bp->b_io_length) != MAX(log->l_mp->m_sb.sb_blocksize,
2541 (__uint32_t)log->l_mp->m_inode_cluster_size))) {
2542 xfs_buf_stale(bp);
2543 error = xfs_bwrite(bp);
2544 } else {
2545 ASSERT(bp->b_target->bt_mount == mp);
2546 bp->b_iodone = xlog_recover_iodone;
2547 xfs_buf_delwri_queue(bp, buffer_list);
2548 }
2549
2550out_release:
2551 xfs_buf_relse(bp);
2552 return error;
2553}
2554
2555/*
2556 * Inode fork owner changes
2557 *
2558 * If we have been told that we have to reparent the inode fork, it's because an
2559 * extent swap operation on a CRC enabled filesystem has been done and we are
2560 * replaying it. We need to walk the BMBT of the appropriate fork and change the
2561 * owners of it.
2562 *
2563 * The complexity here is that we don't have an inode context to work with, so
2564 * after we've replayed the inode we need to instantiate one. This is where the
2565 * fun begins.
2566 *
2567 * We are in the middle of log recovery, so we can't run transactions. That
2568 * means we cannot use cache coherent inode instantiation via xfs_iget(), as
2569 * that will result in the corresponding iput() running the inode through
2570 * xfs_inactive(). If we've just replayed an inode core that changes the link
2571 * count to zero (i.e. it's been unlinked), then xfs_inactive() will run
2572 * transactions (bad!).
2573 *
2574 * So, to avoid this, we instantiate an inode directly from the inode core we've
2575 * just recovered. We have the buffer still locked, and all we really need to
2576 * instantiate is the inode core and the forks being modified. We can do this
2577 * manually, then run the inode btree owner change, and then tear down the
2578 * xfs_inode without having to run any transactions at all.
2579 *
2580 * Also, because we don't have a transaction context available here but need to
2581 * gather all the buffers we modify for writeback so we pass the buffer_list
2582 * instead for the operation to use.
2583 */
2584
2585STATIC int
2586xfs_recover_inode_owner_change(
2587 struct xfs_mount *mp,
2588 struct xfs_dinode *dip,
2589 struct xfs_inode_log_format *in_f,
2590 struct list_head *buffer_list)
2591{
2592 struct xfs_inode *ip;
2593 int error;
2594
2595 ASSERT(in_f->ilf_fields & (XFS_ILOG_DOWNER|XFS_ILOG_AOWNER));
2596
2597 ip = xfs_inode_alloc(mp, in_f->ilf_ino);
2598 if (!ip)
2599 return ENOMEM;
2600
2601 /* instantiate the inode */
2602 xfs_dinode_from_disk(&ip->i_d, dip);
2603 ASSERT(ip->i_d.di_version >= 3);
2604
2605 error = xfs_iformat_fork(ip, dip);
2606 if (error)
2607 goto out_free_ip;
2608
2609
2610 if (in_f->ilf_fields & XFS_ILOG_DOWNER) {
2611 ASSERT(in_f->ilf_fields & XFS_ILOG_DBROOT);
2612 error = xfs_bmbt_change_owner(NULL, ip, XFS_DATA_FORK,
2613 ip->i_ino, buffer_list);
2614 if (error)
2615 goto out_free_ip;
2616 }
2617
2618 if (in_f->ilf_fields & XFS_ILOG_AOWNER) {
2619 ASSERT(in_f->ilf_fields & XFS_ILOG_ABROOT);
2620 error = xfs_bmbt_change_owner(NULL, ip, XFS_ATTR_FORK,
2621 ip->i_ino, buffer_list);
2622 if (error)
2623 goto out_free_ip;
2624 }
2625
2626out_free_ip:
2627 xfs_inode_free(ip);
2628 return error;
2629}
2630
2631STATIC int
2632xlog_recover_inode_pass2(
2633 struct xlog *log,
2634 struct list_head *buffer_list,
2635 struct xlog_recover_item *item,
2636 xfs_lsn_t current_lsn)
2637{
2638 xfs_inode_log_format_t *in_f;
2639 xfs_mount_t *mp = log->l_mp;
2640 xfs_buf_t *bp;
2641 xfs_dinode_t *dip;
2642 int len;
2643 xfs_caddr_t src;
2644 xfs_caddr_t dest;
2645 int error;
2646 int attr_index;
2647 uint fields;
2648 xfs_icdinode_t *dicp;
2649 uint isize;
2650 int need_free = 0;
2651
2652 if (item->ri_buf[0].i_len == sizeof(xfs_inode_log_format_t)) {
2653 in_f = item->ri_buf[0].i_addr;
2654 } else {
2655 in_f = kmem_alloc(sizeof(xfs_inode_log_format_t), KM_SLEEP);
2656 need_free = 1;
2657 error = xfs_inode_item_format_convert(&item->ri_buf[0], in_f);
2658 if (error)
2659 goto error;
2660 }
2661
2662 /*
2663 * Inode buffers can be freed, look out for it,
2664 * and do not replay the inode.
2665 */
2666 if (xlog_check_buffer_cancelled(log, in_f->ilf_blkno,
2667 in_f->ilf_len, 0)) {
2668 error = 0;
2669 trace_xfs_log_recover_inode_cancel(log, in_f);
2670 goto error;
2671 }
2672 trace_xfs_log_recover_inode_recover(log, in_f);
2673
2674 bp = xfs_buf_read(mp->m_ddev_targp, in_f->ilf_blkno, in_f->ilf_len, 0,
2675 &xfs_inode_buf_ops);
2676 if (!bp) {
2677 error = ENOMEM;
2678 goto error;
2679 }
2680 error = bp->b_error;
2681 if (error) {
2682 xfs_buf_ioerror_alert(bp, "xlog_recover_do..(read#2)");
2683 goto out_release;
2684 }
2685 ASSERT(in_f->ilf_fields & XFS_ILOG_CORE);
2686 dip = (xfs_dinode_t *)xfs_buf_offset(bp, in_f->ilf_boffset);
2687
2688 /*
2689 * Make sure the place we're flushing out to really looks
2690 * like an inode!
2691 */
2692 if (unlikely(dip->di_magic != cpu_to_be16(XFS_DINODE_MAGIC))) {
2693 xfs_alert(mp,
2694 "%s: Bad inode magic number, dip = 0x%p, dino bp = 0x%p, ino = %Ld",
2695 __func__, dip, bp, in_f->ilf_ino);
2696 XFS_ERROR_REPORT("xlog_recover_inode_pass2(1)",
2697 XFS_ERRLEVEL_LOW, mp);
2698 error = EFSCORRUPTED;
2699 goto out_release;
2700 }
2701 dicp = item->ri_buf[1].i_addr;
2702 if (unlikely(dicp->di_magic != XFS_DINODE_MAGIC)) {
2703 xfs_alert(mp,
2704 "%s: Bad inode log record, rec ptr 0x%p, ino %Ld",
2705 __func__, item, in_f->ilf_ino);
2706 XFS_ERROR_REPORT("xlog_recover_inode_pass2(2)",
2707 XFS_ERRLEVEL_LOW, mp);
2708 error = EFSCORRUPTED;
2709 goto out_release;
2710 }
2711
2712 /*
2713 * If the inode has an LSN in it, recover the inode only if it's less
2714 * than the lsn of the transaction we are replaying. Note: we still
2715 * need to replay an owner change even though the inode is more recent
2716 * than the transaction as there is no guarantee that all the btree
2717 * blocks are more recent than this transaction, too.
2718 */
2719 if (dip->di_version >= 3) {
2720 xfs_lsn_t lsn = be64_to_cpu(dip->di_lsn);
2721
2722 if (lsn && lsn != -1 && XFS_LSN_CMP(lsn, current_lsn) >= 0) {
2723 trace_xfs_log_recover_inode_skip(log, in_f);
2724 error = 0;
2725 goto out_owner_change;
2726 }
2727 }
2728
2729 /*
2730 * di_flushiter is only valid for v1/2 inodes. All changes for v3 inodes
2731 * are transactional and if ordering is necessary we can determine that
2732 * more accurately by the LSN field in the V3 inode core. Don't trust
2733 * the inode versions we might be changing them here - use the
2734 * superblock flag to determine whether we need to look at di_flushiter
2735 * to skip replay when the on disk inode is newer than the log one
2736 */
2737 if (!xfs_sb_version_hascrc(&mp->m_sb) &&
2738 dicp->di_flushiter < be16_to_cpu(dip->di_flushiter)) {
2739 /*
2740 * Deal with the wrap case, DI_MAX_FLUSH is less
2741 * than smaller numbers
2742 */
2743 if (be16_to_cpu(dip->di_flushiter) == DI_MAX_FLUSH &&
2744 dicp->di_flushiter < (DI_MAX_FLUSH >> 1)) {
2745 /* do nothing */
2746 } else {
2747 trace_xfs_log_recover_inode_skip(log, in_f);
2748 error = 0;
2749 goto out_release;
2750 }
2751 }
2752
2753 /* Take the opportunity to reset the flush iteration count */
2754 dicp->di_flushiter = 0;
2755
2756 if (unlikely(S_ISREG(dicp->di_mode))) {
2757 if ((dicp->di_format != XFS_DINODE_FMT_EXTENTS) &&
2758 (dicp->di_format != XFS_DINODE_FMT_BTREE)) {
2759 XFS_CORRUPTION_ERROR("xlog_recover_inode_pass2(3)",
2760 XFS_ERRLEVEL_LOW, mp, dicp);
2761 xfs_alert(mp,
2762 "%s: Bad regular inode log record, rec ptr 0x%p, "
2763 "ino ptr = 0x%p, ino bp = 0x%p, ino %Ld",
2764 __func__, item, dip, bp, in_f->ilf_ino);
2765 error = EFSCORRUPTED;
2766 goto out_release;
2767 }
2768 } else if (unlikely(S_ISDIR(dicp->di_mode))) {
2769 if ((dicp->di_format != XFS_DINODE_FMT_EXTENTS) &&
2770 (dicp->di_format != XFS_DINODE_FMT_BTREE) &&
2771 (dicp->di_format != XFS_DINODE_FMT_LOCAL)) {
2772 XFS_CORRUPTION_ERROR("xlog_recover_inode_pass2(4)",
2773 XFS_ERRLEVEL_LOW, mp, dicp);
2774 xfs_alert(mp,
2775 "%s: Bad dir inode log record, rec ptr 0x%p, "
2776 "ino ptr = 0x%p, ino bp = 0x%p, ino %Ld",
2777 __func__, item, dip, bp, in_f->ilf_ino);
2778 error = EFSCORRUPTED;
2779 goto out_release;
2780 }
2781 }
2782 if (unlikely(dicp->di_nextents + dicp->di_anextents > dicp->di_nblocks)){
2783 XFS_CORRUPTION_ERROR("xlog_recover_inode_pass2(5)",
2784 XFS_ERRLEVEL_LOW, mp, dicp);
2785 xfs_alert(mp,
2786 "%s: Bad inode log record, rec ptr 0x%p, dino ptr 0x%p, "
2787 "dino bp 0x%p, ino %Ld, total extents = %d, nblocks = %Ld",
2788 __func__, item, dip, bp, in_f->ilf_ino,
2789 dicp->di_nextents + dicp->di_anextents,
2790 dicp->di_nblocks);
2791 error = EFSCORRUPTED;
2792 goto out_release;
2793 }
2794 if (unlikely(dicp->di_forkoff > mp->m_sb.sb_inodesize)) {
2795 XFS_CORRUPTION_ERROR("xlog_recover_inode_pass2(6)",
2796 XFS_ERRLEVEL_LOW, mp, dicp);
2797 xfs_alert(mp,
2798 "%s: Bad inode log record, rec ptr 0x%p, dino ptr 0x%p, "
2799 "dino bp 0x%p, ino %Ld, forkoff 0x%x", __func__,
2800 item, dip, bp, in_f->ilf_ino, dicp->di_forkoff);
2801 error = EFSCORRUPTED;
2802 goto out_release;
2803 }
2804 isize = xfs_icdinode_size(dicp->di_version);
2805 if (unlikely(item->ri_buf[1].i_len > isize)) {
2806 XFS_CORRUPTION_ERROR("xlog_recover_inode_pass2(7)",
2807 XFS_ERRLEVEL_LOW, mp, dicp);
2808 xfs_alert(mp,
2809 "%s: Bad inode log record length %d, rec ptr 0x%p",
2810 __func__, item->ri_buf[1].i_len, item);
2811 error = EFSCORRUPTED;
2812 goto out_release;
2813 }
2814
2815 /* The core is in in-core format */
2816 xfs_dinode_to_disk(dip, dicp);
2817
2818 /* the rest is in on-disk format */
2819 if (item->ri_buf[1].i_len > isize) {
2820 memcpy((char *)dip + isize,
2821 item->ri_buf[1].i_addr + isize,
2822 item->ri_buf[1].i_len - isize);
2823 }
2824
2825 fields = in_f->ilf_fields;
2826 switch (fields & (XFS_ILOG_DEV | XFS_ILOG_UUID)) {
2827 case XFS_ILOG_DEV:
2828 xfs_dinode_put_rdev(dip, in_f->ilf_u.ilfu_rdev);
2829 break;
2830 case XFS_ILOG_UUID:
2831 memcpy(XFS_DFORK_DPTR(dip),
2832 &in_f->ilf_u.ilfu_uuid,
2833 sizeof(uuid_t));
2834 break;
2835 }
2836
2837 if (in_f->ilf_size == 2)
2838 goto out_owner_change;
2839 len = item->ri_buf[2].i_len;
2840 src = item->ri_buf[2].i_addr;
2841 ASSERT(in_f->ilf_size <= 4);
2842 ASSERT((in_f->ilf_size == 3) || (fields & XFS_ILOG_AFORK));
2843 ASSERT(!(fields & XFS_ILOG_DFORK) ||
2844 (len == in_f->ilf_dsize));
2845
2846 switch (fields & XFS_ILOG_DFORK) {
2847 case XFS_ILOG_DDATA:
2848 case XFS_ILOG_DEXT:
2849 memcpy(XFS_DFORK_DPTR(dip), src, len);
2850 break;
2851
2852 case XFS_ILOG_DBROOT:
2853 xfs_bmbt_to_bmdr(mp, (struct xfs_btree_block *)src, len,
2854 (xfs_bmdr_block_t *)XFS_DFORK_DPTR(dip),
2855 XFS_DFORK_DSIZE(dip, mp));
2856 break;
2857
2858 default:
2859 /*
2860 * There are no data fork flags set.
2861 */
2862 ASSERT((fields & XFS_ILOG_DFORK) == 0);
2863 break;
2864 }
2865
2866 /*
2867 * If we logged any attribute data, recover it. There may or
2868 * may not have been any other non-core data logged in this
2869 * transaction.
2870 */
2871 if (in_f->ilf_fields & XFS_ILOG_AFORK) {
2872 if (in_f->ilf_fields & XFS_ILOG_DFORK) {
2873 attr_index = 3;
2874 } else {
2875 attr_index = 2;
2876 }
2877 len = item->ri_buf[attr_index].i_len;
2878 src = item->ri_buf[attr_index].i_addr;
2879 ASSERT(len == in_f->ilf_asize);
2880
2881 switch (in_f->ilf_fields & XFS_ILOG_AFORK) {
2882 case XFS_ILOG_ADATA:
2883 case XFS_ILOG_AEXT:
2884 dest = XFS_DFORK_APTR(dip);
2885 ASSERT(len <= XFS_DFORK_ASIZE(dip, mp));
2886 memcpy(dest, src, len);
2887 break;
2888
2889 case XFS_ILOG_ABROOT:
2890 dest = XFS_DFORK_APTR(dip);
2891 xfs_bmbt_to_bmdr(mp, (struct xfs_btree_block *)src,
2892 len, (xfs_bmdr_block_t*)dest,
2893 XFS_DFORK_ASIZE(dip, mp));
2894 break;
2895
2896 default:
2897 xfs_warn(log->l_mp, "%s: Invalid flag", __func__);
2898 ASSERT(0);
2899 error = EIO;
2900 goto out_release;
2901 }
2902 }
2903
2904out_owner_change:
2905 if (in_f->ilf_fields & (XFS_ILOG_DOWNER|XFS_ILOG_AOWNER))
2906 error = xfs_recover_inode_owner_change(mp, dip, in_f,
2907 buffer_list);
2908 /* re-generate the checksum. */
2909 xfs_dinode_calc_crc(log->l_mp, dip);
2910
2911 ASSERT(bp->b_target->bt_mount == mp);
2912 bp->b_iodone = xlog_recover_iodone;
2913 xfs_buf_delwri_queue(bp, buffer_list);
2914
2915out_release:
2916 xfs_buf_relse(bp);
2917error:
2918 if (need_free)
2919 kmem_free(in_f);
2920 return XFS_ERROR(error);
2921}
2922
2923/*
2924 * Recover QUOTAOFF records. We simply make a note of it in the xlog
2925 * structure, so that we know not to do any dquot item or dquot buffer recovery,
2926 * of that type.
2927 */
2928STATIC int
2929xlog_recover_quotaoff_pass1(
2930 struct xlog *log,
2931 struct xlog_recover_item *item)
2932{
2933 xfs_qoff_logformat_t *qoff_f = item->ri_buf[0].i_addr;
2934 ASSERT(qoff_f);
2935
2936 /*
2937 * The logitem format's flag tells us if this was user quotaoff,
2938 * group/project quotaoff or both.
2939 */
2940 if (qoff_f->qf_flags & XFS_UQUOTA_ACCT)
2941 log->l_quotaoffs_flag |= XFS_DQ_USER;
2942 if (qoff_f->qf_flags & XFS_PQUOTA_ACCT)
2943 log->l_quotaoffs_flag |= XFS_DQ_PROJ;
2944 if (qoff_f->qf_flags & XFS_GQUOTA_ACCT)
2945 log->l_quotaoffs_flag |= XFS_DQ_GROUP;
2946
2947 return (0);
2948}
2949
2950/*
2951 * Recover a dquot record
2952 */
2953STATIC int
2954xlog_recover_dquot_pass2(
2955 struct xlog *log,
2956 struct list_head *buffer_list,
2957 struct xlog_recover_item *item,
2958 xfs_lsn_t current_lsn)
2959{
2960 xfs_mount_t *mp = log->l_mp;
2961 xfs_buf_t *bp;
2962 struct xfs_disk_dquot *ddq, *recddq;
2963 int error;
2964 xfs_dq_logformat_t *dq_f;
2965 uint type;
2966
2967
2968 /*
2969 * Filesystems are required to send in quota flags at mount time.
2970 */
2971 if (mp->m_qflags == 0)
2972 return (0);
2973
2974 recddq = item->ri_buf[1].i_addr;
2975 if (recddq == NULL) {
2976 xfs_alert(log->l_mp, "NULL dquot in %s.", __func__);
2977 return XFS_ERROR(EIO);
2978 }
2979 if (item->ri_buf[1].i_len < sizeof(xfs_disk_dquot_t)) {
2980 xfs_alert(log->l_mp, "dquot too small (%d) in %s.",
2981 item->ri_buf[1].i_len, __func__);
2982 return XFS_ERROR(EIO);
2983 }
2984
2985 /*
2986 * This type of quotas was turned off, so ignore this record.
2987 */
2988 type = recddq->d_flags & (XFS_DQ_USER | XFS_DQ_PROJ | XFS_DQ_GROUP);
2989 ASSERT(type);
2990 if (log->l_quotaoffs_flag & type)
2991 return (0);
2992
2993 /*
2994 * At this point we know that quota was _not_ turned off.
2995 * Since the mount flags are not indicating to us otherwise, this
2996 * must mean that quota is on, and the dquot needs to be replayed.
2997 * Remember that we may not have fully recovered the superblock yet,
2998 * so we can't do the usual trick of looking at the SB quota bits.
2999 *
3000 * The other possibility, of course, is that the quota subsystem was
3001 * removed since the last mount - ENOSYS.
3002 */
3003 dq_f = item->ri_buf[0].i_addr;
3004 ASSERT(dq_f);
3005 error = xfs_dqcheck(mp, recddq, dq_f->qlf_id, 0, XFS_QMOPT_DOWARN,
3006 "xlog_recover_dquot_pass2 (log copy)");
3007 if (error)
3008 return XFS_ERROR(EIO);
3009 ASSERT(dq_f->qlf_len == 1);
3010
3011 error = xfs_trans_read_buf(mp, NULL, mp->m_ddev_targp, dq_f->qlf_blkno,
3012 XFS_FSB_TO_BB(mp, dq_f->qlf_len), 0, &bp,
3013 NULL);
3014 if (error)
3015 return error;
3016
3017 ASSERT(bp);
3018 ddq = (xfs_disk_dquot_t *)xfs_buf_offset(bp, dq_f->qlf_boffset);
3019
3020 /*
3021 * At least the magic num portion should be on disk because this
3022 * was among a chunk of dquots created earlier, and we did some
3023 * minimal initialization then.
3024 */
3025 error = xfs_dqcheck(mp, ddq, dq_f->qlf_id, 0, XFS_QMOPT_DOWARN,
3026 "xlog_recover_dquot_pass2");
3027 if (error) {
3028 xfs_buf_relse(bp);
3029 return XFS_ERROR(EIO);
3030 }
3031
3032 /*
3033 * If the dquot has an LSN in it, recover the dquot only if it's less
3034 * than the lsn of the transaction we are replaying.
3035 */
3036 if (xfs_sb_version_hascrc(&mp->m_sb)) {
3037 struct xfs_dqblk *dqb = (struct xfs_dqblk *)ddq;
3038 xfs_lsn_t lsn = be64_to_cpu(dqb->dd_lsn);
3039
3040 if (lsn && lsn != -1 && XFS_LSN_CMP(lsn, current_lsn) >= 0) {
3041 goto out_release;
3042 }
3043 }
3044
3045 memcpy(ddq, recddq, item->ri_buf[1].i_len);
3046 if (xfs_sb_version_hascrc(&mp->m_sb)) {
3047 xfs_update_cksum((char *)ddq, sizeof(struct xfs_dqblk),
3048 XFS_DQUOT_CRC_OFF);
3049 }
3050
3051 ASSERT(dq_f->qlf_size == 2);
3052 ASSERT(bp->b_target->bt_mount == mp);
3053 bp->b_iodone = xlog_recover_iodone;
3054 xfs_buf_delwri_queue(bp, buffer_list);
3055
3056out_release:
3057 xfs_buf_relse(bp);
3058 return 0;
3059}
3060
3061/*
3062 * This routine is called to create an in-core extent free intent
3063 * item from the efi format structure which was logged on disk.
3064 * It allocates an in-core efi, copies the extents from the format
3065 * structure into it, and adds the efi to the AIL with the given
3066 * LSN.
3067 */
3068STATIC int
3069xlog_recover_efi_pass2(
3070 struct xlog *log,
3071 struct xlog_recover_item *item,
3072 xfs_lsn_t lsn)
3073{
3074 int error;
3075 xfs_mount_t *mp = log->l_mp;
3076 xfs_efi_log_item_t *efip;
3077 xfs_efi_log_format_t *efi_formatp;
3078
3079 efi_formatp = item->ri_buf[0].i_addr;
3080
3081 efip = xfs_efi_init(mp, efi_formatp->efi_nextents);
3082 if ((error = xfs_efi_copy_format(&(item->ri_buf[0]),
3083 &(efip->efi_format)))) {
3084 xfs_efi_item_free(efip);
3085 return error;
3086 }
3087 atomic_set(&efip->efi_next_extent, efi_formatp->efi_nextents);
3088
3089 spin_lock(&log->l_ailp->xa_lock);
3090 /*
3091 * xfs_trans_ail_update() drops the AIL lock.
3092 */
3093 xfs_trans_ail_update(log->l_ailp, &efip->efi_item, lsn);
3094 return 0;
3095}
3096
3097
3098/*
3099 * This routine is called when an efd format structure is found in
3100 * a committed transaction in the log. It's purpose is to cancel
3101 * the corresponding efi if it was still in the log. To do this
3102 * it searches the AIL for the efi with an id equal to that in the
3103 * efd format structure. If we find it, we remove the efi from the
3104 * AIL and free it.
3105 */
3106STATIC int
3107xlog_recover_efd_pass2(
3108 struct xlog *log,
3109 struct xlog_recover_item *item)
3110{
3111 xfs_efd_log_format_t *efd_formatp;
3112 xfs_efi_log_item_t *efip = NULL;
3113 xfs_log_item_t *lip;
3114 __uint64_t efi_id;
3115 struct xfs_ail_cursor cur;
3116 struct xfs_ail *ailp = log->l_ailp;
3117
3118 efd_formatp = item->ri_buf[0].i_addr;
3119 ASSERT((item->ri_buf[0].i_len == (sizeof(xfs_efd_log_format_32_t) +
3120 ((efd_formatp->efd_nextents - 1) * sizeof(xfs_extent_32_t)))) ||
3121 (item->ri_buf[0].i_len == (sizeof(xfs_efd_log_format_64_t) +
3122 ((efd_formatp->efd_nextents - 1) * sizeof(xfs_extent_64_t)))));
3123 efi_id = efd_formatp->efd_efi_id;
3124
3125 /*
3126 * Search for the efi with the id in the efd format structure
3127 * in the AIL.
3128 */
3129 spin_lock(&ailp->xa_lock);
3130 lip = xfs_trans_ail_cursor_first(ailp, &cur, 0);
3131 while (lip != NULL) {
3132 if (lip->li_type == XFS_LI_EFI) {
3133 efip = (xfs_efi_log_item_t *)lip;
3134 if (efip->efi_format.efi_id == efi_id) {
3135 /*
3136 * xfs_trans_ail_delete() drops the
3137 * AIL lock.
3138 */
3139 xfs_trans_ail_delete(ailp, lip,
3140 SHUTDOWN_CORRUPT_INCORE);
3141 xfs_efi_item_free(efip);
3142 spin_lock(&ailp->xa_lock);
3143 break;
3144 }
3145 }
3146 lip = xfs_trans_ail_cursor_next(ailp, &cur);
3147 }
3148 xfs_trans_ail_cursor_done(ailp, &cur);
3149 spin_unlock(&ailp->xa_lock);
3150
3151 return 0;
3152}
3153
3154/*
3155 * This routine is called when an inode create format structure is found in a
3156 * committed transaction in the log. It's purpose is to initialise the inodes
3157 * being allocated on disk. This requires us to get inode cluster buffers that
3158 * match the range to be intialised, stamped with inode templates and written
3159 * by delayed write so that subsequent modifications will hit the cached buffer
3160 * and only need writing out at the end of recovery.
3161 */
3162STATIC int
3163xlog_recover_do_icreate_pass2(
3164 struct xlog *log,
3165 struct list_head *buffer_list,
3166 xlog_recover_item_t *item)
3167{
3168 struct xfs_mount *mp = log->l_mp;
3169 struct xfs_icreate_log *icl;
3170 xfs_agnumber_t agno;
3171 xfs_agblock_t agbno;
3172 unsigned int count;
3173 unsigned int isize;
3174 xfs_agblock_t length;
3175
3176 icl = (struct xfs_icreate_log *)item->ri_buf[0].i_addr;
3177 if (icl->icl_type != XFS_LI_ICREATE) {
3178 xfs_warn(log->l_mp, "xlog_recover_do_icreate_trans: bad type");
3179 return EINVAL;
3180 }
3181
3182 if (icl->icl_size != 1) {
3183 xfs_warn(log->l_mp, "xlog_recover_do_icreate_trans: bad icl size");
3184 return EINVAL;
3185 }
3186
3187 agno = be32_to_cpu(icl->icl_ag);
3188 if (agno >= mp->m_sb.sb_agcount) {
3189 xfs_warn(log->l_mp, "xlog_recover_do_icreate_trans: bad agno");
3190 return EINVAL;
3191 }
3192 agbno = be32_to_cpu(icl->icl_agbno);
3193 if (!agbno || agbno == NULLAGBLOCK || agbno >= mp->m_sb.sb_agblocks) {
3194 xfs_warn(log->l_mp, "xlog_recover_do_icreate_trans: bad agbno");
3195 return EINVAL;
3196 }
3197 isize = be32_to_cpu(icl->icl_isize);
3198 if (isize != mp->m_sb.sb_inodesize) {
3199 xfs_warn(log->l_mp, "xlog_recover_do_icreate_trans: bad isize");
3200 return EINVAL;
3201 }
3202 count = be32_to_cpu(icl->icl_count);
3203 if (!count) {
3204 xfs_warn(log->l_mp, "xlog_recover_do_icreate_trans: bad count");
3205 return EINVAL;
3206 }
3207 length = be32_to_cpu(icl->icl_length);
3208 if (!length || length >= mp->m_sb.sb_agblocks) {
3209 xfs_warn(log->l_mp, "xlog_recover_do_icreate_trans: bad length");
3210 return EINVAL;
3211 }
3212
3213 /* existing allocation is fixed value */
3214 ASSERT(count == mp->m_ialloc_inos);
3215 ASSERT(length == mp->m_ialloc_blks);
3216 if (count != mp->m_ialloc_inos ||
3217 length != mp->m_ialloc_blks) {
3218 xfs_warn(log->l_mp, "xlog_recover_do_icreate_trans: bad count 2");
3219 return EINVAL;
3220 }
3221
3222 /*
3223 * Inode buffers can be freed. Do not replay the inode initialisation as
3224 * we could be overwriting something written after this inode buffer was
3225 * cancelled.
3226 *
3227 * XXX: we need to iterate all buffers and only init those that are not
3228 * cancelled. I think that a more fine grained factoring of
3229 * xfs_ialloc_inode_init may be appropriate here to enable this to be
3230 * done easily.
3231 */
3232 if (xlog_check_buffer_cancelled(log,
3233 XFS_AGB_TO_DADDR(mp, agno, agbno), length, 0))
3234 return 0;
3235
3236 xfs_ialloc_inode_init(mp, NULL, buffer_list, agno, agbno, length,
3237 be32_to_cpu(icl->icl_gen));
3238 return 0;
3239}
3240
3241/*
3242 * Free up any resources allocated by the transaction
3243 *
3244 * Remember that EFIs, EFDs, and IUNLINKs are handled later.
3245 */
3246STATIC void
3247xlog_recover_free_trans(
3248 struct xlog_recover *trans)
3249{
3250 xlog_recover_item_t *item, *n;
3251 int i;
3252
3253 list_for_each_entry_safe(item, n, &trans->r_itemq, ri_list) {
3254 /* Free the regions in the item. */
3255 list_del(&item->ri_list);
3256 for (i = 0; i < item->ri_cnt; i++)
3257 kmem_free(item->ri_buf[i].i_addr);
3258 /* Free the item itself */
3259 kmem_free(item->ri_buf);
3260 kmem_free(item);
3261 }
3262 /* Free the transaction recover structure */
3263 kmem_free(trans);
3264}
3265
3266STATIC void
3267xlog_recover_buffer_ra_pass2(
3268 struct xlog *log,
3269 struct xlog_recover_item *item)
3270{
3271 struct xfs_buf_log_format *buf_f = item->ri_buf[0].i_addr;
3272 struct xfs_mount *mp = log->l_mp;
3273
3274 if (xlog_peek_buffer_cancelled(log, buf_f->blf_blkno,
3275 buf_f->blf_len, buf_f->blf_flags)) {
3276 return;
3277 }
3278
3279 xfs_buf_readahead(mp->m_ddev_targp, buf_f->blf_blkno,
3280 buf_f->blf_len, NULL);
3281}
3282
3283STATIC void
3284xlog_recover_inode_ra_pass2(
3285 struct xlog *log,
3286 struct xlog_recover_item *item)
3287{
3288 struct xfs_inode_log_format ilf_buf;
3289 struct xfs_inode_log_format *ilfp;
3290 struct xfs_mount *mp = log->l_mp;
3291 int error;
3292
3293 if (item->ri_buf[0].i_len == sizeof(struct xfs_inode_log_format)) {
3294 ilfp = item->ri_buf[0].i_addr;
3295 } else {
3296 ilfp = &ilf_buf;
3297 memset(ilfp, 0, sizeof(*ilfp));
3298 error = xfs_inode_item_format_convert(&item->ri_buf[0], ilfp);
3299 if (error)
3300 return;
3301 }
3302
3303 if (xlog_peek_buffer_cancelled(log, ilfp->ilf_blkno, ilfp->ilf_len, 0))
3304 return;
3305
3306 xfs_buf_readahead(mp->m_ddev_targp, ilfp->ilf_blkno,
3307 ilfp->ilf_len, &xfs_inode_buf_ra_ops);
3308}
3309
3310STATIC void
3311xlog_recover_dquot_ra_pass2(
3312 struct xlog *log,
3313 struct xlog_recover_item *item)
3314{
3315 struct xfs_mount *mp = log->l_mp;
3316 struct xfs_disk_dquot *recddq;
3317 struct xfs_dq_logformat *dq_f;
3318 uint type;
3319
3320
3321 if (mp->m_qflags == 0)
3322 return;
3323
3324 recddq = item->ri_buf[1].i_addr;
3325 if (recddq == NULL)
3326 return;
3327 if (item->ri_buf[1].i_len < sizeof(struct xfs_disk_dquot))
3328 return;
3329
3330 type = recddq->d_flags & (XFS_DQ_USER | XFS_DQ_PROJ | XFS_DQ_GROUP);
3331 ASSERT(type);
3332 if (log->l_quotaoffs_flag & type)
3333 return;
3334
3335 dq_f = item->ri_buf[0].i_addr;
3336 ASSERT(dq_f);
3337 ASSERT(dq_f->qlf_len == 1);
3338
3339 xfs_buf_readahead(mp->m_ddev_targp, dq_f->qlf_blkno,
3340 XFS_FSB_TO_BB(mp, dq_f->qlf_len), NULL);
3341}
3342
3343STATIC void
3344xlog_recover_ra_pass2(
3345 struct xlog *log,
3346 struct xlog_recover_item *item)
3347{
3348 switch (ITEM_TYPE(item)) {
3349 case XFS_LI_BUF:
3350 xlog_recover_buffer_ra_pass2(log, item);
3351 break;
3352 case XFS_LI_INODE:
3353 xlog_recover_inode_ra_pass2(log, item);
3354 break;
3355 case XFS_LI_DQUOT:
3356 xlog_recover_dquot_ra_pass2(log, item);
3357 break;
3358 case XFS_LI_EFI:
3359 case XFS_LI_EFD:
3360 case XFS_LI_QUOTAOFF:
3361 default:
3362 break;
3363 }
3364}
3365
3366STATIC int
3367xlog_recover_commit_pass1(
3368 struct xlog *log,
3369 struct xlog_recover *trans,
3370 struct xlog_recover_item *item)
3371{
3372 trace_xfs_log_recover_item_recover(log, trans, item, XLOG_RECOVER_PASS1);
3373
3374 switch (ITEM_TYPE(item)) {
3375 case XFS_LI_BUF:
3376 return xlog_recover_buffer_pass1(log, item);
3377 case XFS_LI_QUOTAOFF:
3378 return xlog_recover_quotaoff_pass1(log, item);
3379 case XFS_LI_INODE:
3380 case XFS_LI_EFI:
3381 case XFS_LI_EFD:
3382 case XFS_LI_DQUOT:
3383 case XFS_LI_ICREATE:
3384 /* nothing to do in pass 1 */
3385 return 0;
3386 default:
3387 xfs_warn(log->l_mp, "%s: invalid item type (%d)",
3388 __func__, ITEM_TYPE(item));
3389 ASSERT(0);
3390 return XFS_ERROR(EIO);
3391 }
3392}
3393
3394STATIC int
3395xlog_recover_commit_pass2(
3396 struct xlog *log,
3397 struct xlog_recover *trans,
3398 struct list_head *buffer_list,
3399 struct xlog_recover_item *item)
3400{
3401 trace_xfs_log_recover_item_recover(log, trans, item, XLOG_RECOVER_PASS2);
3402
3403 switch (ITEM_TYPE(item)) {
3404 case XFS_LI_BUF:
3405 return xlog_recover_buffer_pass2(log, buffer_list, item,
3406 trans->r_lsn);
3407 case XFS_LI_INODE:
3408 return xlog_recover_inode_pass2(log, buffer_list, item,
3409 trans->r_lsn);
3410 case XFS_LI_EFI:
3411 return xlog_recover_efi_pass2(log, item, trans->r_lsn);
3412 case XFS_LI_EFD:
3413 return xlog_recover_efd_pass2(log, item);
3414 case XFS_LI_DQUOT:
3415 return xlog_recover_dquot_pass2(log, buffer_list, item,
3416 trans->r_lsn);
3417 case XFS_LI_ICREATE:
3418 return xlog_recover_do_icreate_pass2(log, buffer_list, item);
3419 case XFS_LI_QUOTAOFF:
3420 /* nothing to do in pass2 */
3421 return 0;
3422 default:
3423 xfs_warn(log->l_mp, "%s: invalid item type (%d)",
3424 __func__, ITEM_TYPE(item));
3425 ASSERT(0);
3426 return XFS_ERROR(EIO);
3427 }
3428}
3429
3430STATIC int
3431xlog_recover_items_pass2(
3432 struct xlog *log,
3433 struct xlog_recover *trans,
3434 struct list_head *buffer_list,
3435 struct list_head *item_list)
3436{
3437 struct xlog_recover_item *item;
3438 int error = 0;
3439
3440 list_for_each_entry(item, item_list, ri_list) {
3441 error = xlog_recover_commit_pass2(log, trans,
3442 buffer_list, item);
3443 if (error)
3444 return error;
3445 }
3446
3447 return error;
3448}
3449
3450/*
3451 * Perform the transaction.
3452 *
3453 * If the transaction modifies a buffer or inode, do it now. Otherwise,
3454 * EFIs and EFDs get queued up by adding entries into the AIL for them.
3455 */
3456STATIC int
3457xlog_recover_commit_trans(
3458 struct xlog *log,
3459 struct xlog_recover *trans,
3460 int pass)
3461{
3462 int error = 0;
3463 int error2;
3464 int items_queued = 0;
3465 struct xlog_recover_item *item;
3466 struct xlog_recover_item *next;
3467 LIST_HEAD (buffer_list);
3468 LIST_HEAD (ra_list);
3469 LIST_HEAD (done_list);
3470
3471 #define XLOG_RECOVER_COMMIT_QUEUE_MAX 100
3472
3473 hlist_del(&trans->r_list);
3474
3475 error = xlog_recover_reorder_trans(log, trans, pass);
3476 if (error)
3477 return error;
3478
3479 list_for_each_entry_safe(item, next, &trans->r_itemq, ri_list) {
3480 switch (pass) {
3481 case XLOG_RECOVER_PASS1:
3482 error = xlog_recover_commit_pass1(log, trans, item);
3483 break;
3484 case XLOG_RECOVER_PASS2:
3485 xlog_recover_ra_pass2(log, item);
3486 list_move_tail(&item->ri_list, &ra_list);
3487 items_queued++;
3488 if (items_queued >= XLOG_RECOVER_COMMIT_QUEUE_MAX) {
3489 error = xlog_recover_items_pass2(log, trans,
3490 &buffer_list, &ra_list);
3491 list_splice_tail_init(&ra_list, &done_list);
3492 items_queued = 0;
3493 }
3494
3495 break;
3496 default:
3497 ASSERT(0);
3498 }
3499
3500 if (error)
3501 goto out;
3502 }
3503
3504out:
3505 if (!list_empty(&ra_list)) {
3506 if (!error)
3507 error = xlog_recover_items_pass2(log, trans,
3508 &buffer_list, &ra_list);
3509 list_splice_tail_init(&ra_list, &done_list);
3510 }
3511
3512 if (!list_empty(&done_list))
3513 list_splice_init(&done_list, &trans->r_itemq);
3514
3515 xlog_recover_free_trans(trans);
3516
3517 error2 = xfs_buf_delwri_submit(&buffer_list);
3518 return error ? error : error2;
3519}
3520
3521STATIC int
3522xlog_recover_unmount_trans(
3523 struct xlog *log,
3524 struct xlog_recover *trans)
3525{
3526 /* Do nothing now */
3527 xfs_warn(log->l_mp, "%s: Unmount LR", __func__);
3528 return 0;
3529}
3530
3531/*
3532 * There are two valid states of the r_state field. 0 indicates that the
3533 * transaction structure is in a normal state. We have either seen the
3534 * start of the transaction or the last operation we added was not a partial
3535 * operation. If the last operation we added to the transaction was a
3536 * partial operation, we need to mark r_state with XLOG_WAS_CONT_TRANS.
3537 *
3538 * NOTE: skip LRs with 0 data length.
3539 */
3540STATIC int
3541xlog_recover_process_data(
3542 struct xlog *log,
3543 struct hlist_head rhash[],
3544 struct xlog_rec_header *rhead,
3545 xfs_caddr_t dp,
3546 int pass)
3547{
3548 xfs_caddr_t lp;
3549 int num_logops;
3550 xlog_op_header_t *ohead;
3551 xlog_recover_t *trans;
3552 xlog_tid_t tid;
3553 int error;
3554 unsigned long hash;
3555 uint flags;
3556
3557 lp = dp + be32_to_cpu(rhead->h_len);
3558 num_logops = be32_to_cpu(rhead->h_num_logops);
3559
3560 /* check the log format matches our own - else we can't recover */
3561 if (xlog_header_check_recover(log->l_mp, rhead))
3562 return (XFS_ERROR(EIO));
3563
3564 while ((dp < lp) && num_logops) {
3565 ASSERT(dp + sizeof(xlog_op_header_t) <= lp);
3566 ohead = (xlog_op_header_t *)dp;
3567 dp += sizeof(xlog_op_header_t);
3568 if (ohead->oh_clientid != XFS_TRANSACTION &&
3569 ohead->oh_clientid != XFS_LOG) {
3570 xfs_warn(log->l_mp, "%s: bad clientid 0x%x",
3571 __func__, ohead->oh_clientid);
3572 ASSERT(0);
3573 return (XFS_ERROR(EIO));
3574 }
3575 tid = be32_to_cpu(ohead->oh_tid);
3576 hash = XLOG_RHASH(tid);
3577 trans = xlog_recover_find_tid(&rhash[hash], tid);
3578 if (trans == NULL) { /* not found; add new tid */
3579 if (ohead->oh_flags & XLOG_START_TRANS)
3580 xlog_recover_new_tid(&rhash[hash], tid,
3581 be64_to_cpu(rhead->h_lsn));
3582 } else {
3583 if (dp + be32_to_cpu(ohead->oh_len) > lp) {
3584 xfs_warn(log->l_mp, "%s: bad length 0x%x",
3585 __func__, be32_to_cpu(ohead->oh_len));
3586 WARN_ON(1);
3587 return (XFS_ERROR(EIO));
3588 }
3589 flags = ohead->oh_flags & ~XLOG_END_TRANS;
3590 if (flags & XLOG_WAS_CONT_TRANS)
3591 flags &= ~XLOG_CONTINUE_TRANS;
3592 switch (flags) {
3593 case XLOG_COMMIT_TRANS:
3594 error = xlog_recover_commit_trans(log,
3595 trans, pass);
3596 break;
3597 case XLOG_UNMOUNT_TRANS:
3598 error = xlog_recover_unmount_trans(log, trans);
3599 break;
3600 case XLOG_WAS_CONT_TRANS:
3601 error = xlog_recover_add_to_cont_trans(log,
3602 trans, dp,
3603 be32_to_cpu(ohead->oh_len));
3604 break;
3605 case XLOG_START_TRANS:
3606 xfs_warn(log->l_mp, "%s: bad transaction",
3607 __func__);
3608 ASSERT(0);
3609 error = XFS_ERROR(EIO);
3610 break;
3611 case 0:
3612 case XLOG_CONTINUE_TRANS:
3613 error = xlog_recover_add_to_trans(log, trans,
3614 dp, be32_to_cpu(ohead->oh_len));
3615 break;
3616 default:
3617 xfs_warn(log->l_mp, "%s: bad flag 0x%x",
3618 __func__, flags);
3619 ASSERT(0);
3620 error = XFS_ERROR(EIO);
3621 break;
3622 }
3623 if (error) {
3624 xlog_recover_free_trans(trans);
3625 return error;
3626 }
3627 }
3628 dp += be32_to_cpu(ohead->oh_len);
3629 num_logops--;
3630 }
3631 return 0;
3632}
3633
3634/*
3635 * Process an extent free intent item that was recovered from
3636 * the log. We need to free the extents that it describes.
3637 */
3638STATIC int
3639xlog_recover_process_efi(
3640 xfs_mount_t *mp,
3641 xfs_efi_log_item_t *efip)
3642{
3643 xfs_efd_log_item_t *efdp;
3644 xfs_trans_t *tp;
3645 int i;
3646 int error = 0;
3647 xfs_extent_t *extp;
3648 xfs_fsblock_t startblock_fsb;
3649
3650 ASSERT(!test_bit(XFS_EFI_RECOVERED, &efip->efi_flags));
3651
3652 /*
3653 * First check the validity of the extents described by the
3654 * EFI. If any are bad, then assume that all are bad and
3655 * just toss the EFI.
3656 */
3657 for (i = 0; i < efip->efi_format.efi_nextents; i++) {
3658 extp = &(efip->efi_format.efi_extents[i]);
3659 startblock_fsb = XFS_BB_TO_FSB(mp,
3660 XFS_FSB_TO_DADDR(mp, extp->ext_start));
3661 if ((startblock_fsb == 0) ||
3662 (extp->ext_len == 0) ||
3663 (startblock_fsb >= mp->m_sb.sb_dblocks) ||
3664 (extp->ext_len >= mp->m_sb.sb_agblocks)) {
3665 /*
3666 * This will pull the EFI from the AIL and
3667 * free the memory associated with it.
3668 */
3669 set_bit(XFS_EFI_RECOVERED, &efip->efi_flags);
3670 xfs_efi_release(efip, efip->efi_format.efi_nextents);
3671 return XFS_ERROR(EIO);
3672 }
3673 }
3674
3675 tp = xfs_trans_alloc(mp, 0);
3676 error = xfs_trans_reserve(tp, &M_RES(mp)->tr_itruncate, 0, 0);
3677 if (error)
3678 goto abort_error;
3679 efdp = xfs_trans_get_efd(tp, efip, efip->efi_format.efi_nextents);
3680
3681 for (i = 0; i < efip->efi_format.efi_nextents; i++) {
3682 extp = &(efip->efi_format.efi_extents[i]);
3683 error = xfs_free_extent(tp, extp->ext_start, extp->ext_len);
3684 if (error)
3685 goto abort_error;
3686 xfs_trans_log_efd_extent(tp, efdp, extp->ext_start,
3687 extp->ext_len);
3688 }
3689
3690 set_bit(XFS_EFI_RECOVERED, &efip->efi_flags);
3691 error = xfs_trans_commit(tp, 0);
3692 return error;
3693
3694abort_error:
3695 xfs_trans_cancel(tp, XFS_TRANS_ABORT);
3696 return error;
3697}
3698
3699/*
3700 * When this is called, all of the EFIs which did not have
3701 * corresponding EFDs should be in the AIL. What we do now
3702 * is free the extents associated with each one.
3703 *
3704 * Since we process the EFIs in normal transactions, they
3705 * will be removed at some point after the commit. This prevents
3706 * us from just walking down the list processing each one.
3707 * We'll use a flag in the EFI to skip those that we've already
3708 * processed and use the AIL iteration mechanism's generation
3709 * count to try to speed this up at least a bit.
3710 *
3711 * When we start, we know that the EFIs are the only things in
3712 * the AIL. As we process them, however, other items are added
3713 * to the AIL. Since everything added to the AIL must come after
3714 * everything already in the AIL, we stop processing as soon as
3715 * we see something other than an EFI in the AIL.
3716 */
3717STATIC int
3718xlog_recover_process_efis(
3719 struct xlog *log)
3720{
3721 xfs_log_item_t *lip;
3722 xfs_efi_log_item_t *efip;
3723 int error = 0;
3724 struct xfs_ail_cursor cur;
3725 struct xfs_ail *ailp;
3726
3727 ailp = log->l_ailp;
3728 spin_lock(&ailp->xa_lock);
3729 lip = xfs_trans_ail_cursor_first(ailp, &cur, 0);
3730 while (lip != NULL) {
3731 /*
3732 * We're done when we see something other than an EFI.
3733 * There should be no EFIs left in the AIL now.
3734 */
3735 if (lip->li_type != XFS_LI_EFI) {
3736#ifdef DEBUG
3737 for (; lip; lip = xfs_trans_ail_cursor_next(ailp, &cur))
3738 ASSERT(lip->li_type != XFS_LI_EFI);
3739#endif
3740 break;
3741 }
3742
3743 /*
3744 * Skip EFIs that we've already processed.
3745 */
3746 efip = (xfs_efi_log_item_t *)lip;
3747 if (test_bit(XFS_EFI_RECOVERED, &efip->efi_flags)) {
3748 lip = xfs_trans_ail_cursor_next(ailp, &cur);
3749 continue;
3750 }
3751
3752 spin_unlock(&ailp->xa_lock);
3753 error = xlog_recover_process_efi(log->l_mp, efip);
3754 spin_lock(&ailp->xa_lock);
3755 if (error)
3756 goto out;
3757 lip = xfs_trans_ail_cursor_next(ailp, &cur);
3758 }
3759out:
3760 xfs_trans_ail_cursor_done(ailp, &cur);
3761 spin_unlock(&ailp->xa_lock);
3762 return error;
3763}
3764
3765/*
3766 * This routine performs a transaction to null out a bad inode pointer
3767 * in an agi unlinked inode hash bucket.
3768 */
3769STATIC void
3770xlog_recover_clear_agi_bucket(
3771 xfs_mount_t *mp,
3772 xfs_agnumber_t agno,
3773 int bucket)
3774{
3775 xfs_trans_t *tp;
3776 xfs_agi_t *agi;
3777 xfs_buf_t *agibp;
3778 int offset;
3779 int error;
3780
3781 tp = xfs_trans_alloc(mp, XFS_TRANS_CLEAR_AGI_BUCKET);
3782 error = xfs_trans_reserve(tp, &M_RES(mp)->tr_clearagi, 0, 0);
3783 if (error)
3784 goto out_abort;
3785
3786 error = xfs_read_agi(mp, tp, agno, &agibp);
3787 if (error)
3788 goto out_abort;
3789
3790 agi = XFS_BUF_TO_AGI(agibp);
3791 agi->agi_unlinked[bucket] = cpu_to_be32(NULLAGINO);
3792 offset = offsetof(xfs_agi_t, agi_unlinked) +
3793 (sizeof(xfs_agino_t) * bucket);
3794 xfs_trans_log_buf(tp, agibp, offset,
3795 (offset + sizeof(xfs_agino_t) - 1));
3796
3797 error = xfs_trans_commit(tp, 0);
3798 if (error)
3799 goto out_error;
3800 return;
3801
3802out_abort:
3803 xfs_trans_cancel(tp, XFS_TRANS_ABORT);
3804out_error:
3805 xfs_warn(mp, "%s: failed to clear agi %d. Continuing.", __func__, agno);
3806 return;
3807}
3808
3809STATIC xfs_agino_t
3810xlog_recover_process_one_iunlink(
3811 struct xfs_mount *mp,
3812 xfs_agnumber_t agno,
3813 xfs_agino_t agino,
3814 int bucket)
3815{
3816 struct xfs_buf *ibp;
3817 struct xfs_dinode *dip;
3818 struct xfs_inode *ip;
3819 xfs_ino_t ino;
3820 int error;
3821
3822 ino = XFS_AGINO_TO_INO(mp, agno, agino);
3823 error = xfs_iget(mp, NULL, ino, 0, 0, &ip);
3824 if (error)
3825 goto fail;
3826
3827 /*
3828 * Get the on disk inode to find the next inode in the bucket.
3829 */
3830 error = xfs_imap_to_bp(mp, NULL, &ip->i_imap, &dip, &ibp, 0, 0);
3831 if (error)
3832 goto fail_iput;
3833
3834 ASSERT(ip->i_d.di_nlink == 0);
3835 ASSERT(ip->i_d.di_mode != 0);
3836
3837 /* setup for the next pass */
3838 agino = be32_to_cpu(dip->di_next_unlinked);
3839 xfs_buf_relse(ibp);
3840
3841 /*
3842 * Prevent any DMAPI event from being sent when the reference on
3843 * the inode is dropped.
3844 */
3845 ip->i_d.di_dmevmask = 0;
3846
3847 IRELE(ip);
3848 return agino;
3849
3850 fail_iput:
3851 IRELE(ip);
3852 fail:
3853 /*
3854 * We can't read in the inode this bucket points to, or this inode
3855 * is messed up. Just ditch this bucket of inodes. We will lose
3856 * some inodes and space, but at least we won't hang.
3857 *
3858 * Call xlog_recover_clear_agi_bucket() to perform a transaction to
3859 * clear the inode pointer in the bucket.
3860 */
3861 xlog_recover_clear_agi_bucket(mp, agno, bucket);
3862 return NULLAGINO;
3863}
3864
3865/*
3866 * xlog_iunlink_recover
3867 *
3868 * This is called during recovery to process any inodes which
3869 * we unlinked but not freed when the system crashed. These
3870 * inodes will be on the lists in the AGI blocks. What we do
3871 * here is scan all the AGIs and fully truncate and free any
3872 * inodes found on the lists. Each inode is removed from the
3873 * lists when it has been fully truncated and is freed. The
3874 * freeing of the inode and its removal from the list must be
3875 * atomic.
3876 */
3877STATIC void
3878xlog_recover_process_iunlinks(
3879 struct xlog *log)
3880{
3881 xfs_mount_t *mp;
3882 xfs_agnumber_t agno;
3883 xfs_agi_t *agi;
3884 xfs_buf_t *agibp;
3885 xfs_agino_t agino;
3886 int bucket;
3887 int error;
3888 uint mp_dmevmask;
3889
3890 mp = log->l_mp;
3891
3892 /*
3893 * Prevent any DMAPI event from being sent while in this function.
3894 */
3895 mp_dmevmask = mp->m_dmevmask;
3896 mp->m_dmevmask = 0;
3897
3898 for (agno = 0; agno < mp->m_sb.sb_agcount; agno++) {
3899 /*
3900 * Find the agi for this ag.
3901 */
3902 error = xfs_read_agi(mp, NULL, agno, &agibp);
3903 if (error) {
3904 /*
3905 * AGI is b0rked. Don't process it.
3906 *
3907 * We should probably mark the filesystem as corrupt
3908 * after we've recovered all the ag's we can....
3909 */
3910 continue;
3911 }
3912 /*
3913 * Unlock the buffer so that it can be acquired in the normal
3914 * course of the transaction to truncate and free each inode.
3915 * Because we are not racing with anyone else here for the AGI
3916 * buffer, we don't even need to hold it locked to read the
3917 * initial unlinked bucket entries out of the buffer. We keep
3918 * buffer reference though, so that it stays pinned in memory
3919 * while we need the buffer.
3920 */
3921 agi = XFS_BUF_TO_AGI(agibp);
3922 xfs_buf_unlock(agibp);
3923
3924 for (bucket = 0; bucket < XFS_AGI_UNLINKED_BUCKETS; bucket++) {
3925 agino = be32_to_cpu(agi->agi_unlinked[bucket]);
3926 while (agino != NULLAGINO) {
3927 agino = xlog_recover_process_one_iunlink(mp,
3928 agno, agino, bucket);
3929 }
3930 }
3931 xfs_buf_rele(agibp);
3932 }
3933
3934 mp->m_dmevmask = mp_dmevmask;
3935}
3936
3937/*
3938 * Upack the log buffer data and crc check it. If the check fails, issue a
3939 * warning if and only if the CRC in the header is non-zero. This makes the
3940 * check an advisory warning, and the zero CRC check will prevent failure
3941 * warnings from being emitted when upgrading the kernel from one that does not
3942 * add CRCs by default.
3943 *
3944 * When filesystems are CRC enabled, this CRC mismatch becomes a fatal log
3945 * corruption failure
3946 */
3947STATIC int
3948xlog_unpack_data_crc(
3949 struct xlog_rec_header *rhead,
3950 xfs_caddr_t dp,
3951 struct xlog *log)
3952{
3953 __le32 crc;
3954
3955 crc = xlog_cksum(log, rhead, dp, be32_to_cpu(rhead->h_len));
3956 if (crc != rhead->h_crc) {
3957 if (rhead->h_crc || xfs_sb_version_hascrc(&log->l_mp->m_sb)) {
3958 xfs_alert(log->l_mp,
3959 "log record CRC mismatch: found 0x%x, expected 0x%x.",
3960 le32_to_cpu(rhead->h_crc),
3961 le32_to_cpu(crc));
3962 xfs_hex_dump(dp, 32);
3963 }
3964
3965 /*
3966 * If we've detected a log record corruption, then we can't
3967 * recover past this point. Abort recovery if we are enforcing
3968 * CRC protection by punting an error back up the stack.
3969 */
3970 if (xfs_sb_version_hascrc(&log->l_mp->m_sb))
3971 return EFSCORRUPTED;
3972 }
3973
3974 return 0;
3975}
3976
3977STATIC int
3978xlog_unpack_data(
3979 struct xlog_rec_header *rhead,
3980 xfs_caddr_t dp,
3981 struct xlog *log)
3982{
3983 int i, j, k;
3984 int error;
3985
3986 error = xlog_unpack_data_crc(rhead, dp, log);
3987 if (error)
3988 return error;
3989
3990 for (i = 0; i < BTOBB(be32_to_cpu(rhead->h_len)) &&
3991 i < (XLOG_HEADER_CYCLE_SIZE / BBSIZE); i++) {
3992 *(__be32 *)dp = *(__be32 *)&rhead->h_cycle_data[i];
3993 dp += BBSIZE;
3994 }
3995
3996 if (xfs_sb_version_haslogv2(&log->l_mp->m_sb)) {
3997 xlog_in_core_2_t *xhdr = (xlog_in_core_2_t *)rhead;
3998 for ( ; i < BTOBB(be32_to_cpu(rhead->h_len)); i++) {
3999 j = i / (XLOG_HEADER_CYCLE_SIZE / BBSIZE);
4000 k = i % (XLOG_HEADER_CYCLE_SIZE / BBSIZE);
4001 *(__be32 *)dp = xhdr[j].hic_xheader.xh_cycle_data[k];
4002 dp += BBSIZE;
4003 }
4004 }
4005
4006 return 0;
4007}
4008
4009STATIC int
4010xlog_valid_rec_header(
4011 struct xlog *log,
4012 struct xlog_rec_header *rhead,
4013 xfs_daddr_t blkno)
4014{
4015 int hlen;
4016
4017 if (unlikely(rhead->h_magicno != cpu_to_be32(XLOG_HEADER_MAGIC_NUM))) {
4018 XFS_ERROR_REPORT("xlog_valid_rec_header(1)",
4019 XFS_ERRLEVEL_LOW, log->l_mp);
4020 return XFS_ERROR(EFSCORRUPTED);
4021 }
4022 if (unlikely(
4023 (!rhead->h_version ||
4024 (be32_to_cpu(rhead->h_version) & (~XLOG_VERSION_OKBITS))))) {
4025 xfs_warn(log->l_mp, "%s: unrecognised log version (%d).",
4026 __func__, be32_to_cpu(rhead->h_version));
4027 return XFS_ERROR(EIO);
4028 }
4029
4030 /* LR body must have data or it wouldn't have been written */
4031 hlen = be32_to_cpu(rhead->h_len);
4032 if (unlikely( hlen <= 0 || hlen > INT_MAX )) {
4033 XFS_ERROR_REPORT("xlog_valid_rec_header(2)",
4034 XFS_ERRLEVEL_LOW, log->l_mp);
4035 return XFS_ERROR(EFSCORRUPTED);
4036 }
4037 if (unlikely( blkno > log->l_logBBsize || blkno > INT_MAX )) {
4038 XFS_ERROR_REPORT("xlog_valid_rec_header(3)",
4039 XFS_ERRLEVEL_LOW, log->l_mp);
4040 return XFS_ERROR(EFSCORRUPTED);
4041 }
4042 return 0;
4043}
4044
4045/*
4046 * Read the log from tail to head and process the log records found.
4047 * Handle the two cases where the tail and head are in the same cycle
4048 * and where the active portion of the log wraps around the end of
4049 * the physical log separately. The pass parameter is passed through
4050 * to the routines called to process the data and is not looked at
4051 * here.
4052 */
4053STATIC int
4054xlog_do_recovery_pass(
4055 struct xlog *log,
4056 xfs_daddr_t head_blk,
4057 xfs_daddr_t tail_blk,
4058 int pass)
4059{
4060 xlog_rec_header_t *rhead;
4061 xfs_daddr_t blk_no;
4062 xfs_caddr_t offset;
4063 xfs_buf_t *hbp, *dbp;
4064 int error = 0, h_size;
4065 int bblks, split_bblks;
4066 int hblks, split_hblks, wrapped_hblks;
4067 struct hlist_head rhash[XLOG_RHASH_SIZE];
4068
4069 ASSERT(head_blk != tail_blk);
4070
4071 /*
4072 * Read the header of the tail block and get the iclog buffer size from
4073 * h_size. Use this to tell how many sectors make up the log header.
4074 */
4075 if (xfs_sb_version_haslogv2(&log->l_mp->m_sb)) {
4076 /*
4077 * When using variable length iclogs, read first sector of
4078 * iclog header and extract the header size from it. Get a
4079 * new hbp that is the correct size.
4080 */
4081 hbp = xlog_get_bp(log, 1);
4082 if (!hbp)
4083 return ENOMEM;
4084
4085 error = xlog_bread(log, tail_blk, 1, hbp, &offset);
4086 if (error)
4087 goto bread_err1;
4088
4089 rhead = (xlog_rec_header_t *)offset;
4090 error = xlog_valid_rec_header(log, rhead, tail_blk);
4091 if (error)
4092 goto bread_err1;
4093 h_size = be32_to_cpu(rhead->h_size);
4094 if ((be32_to_cpu(rhead->h_version) & XLOG_VERSION_2) &&
4095 (h_size > XLOG_HEADER_CYCLE_SIZE)) {
4096 hblks = h_size / XLOG_HEADER_CYCLE_SIZE;
4097 if (h_size % XLOG_HEADER_CYCLE_SIZE)
4098 hblks++;
4099 xlog_put_bp(hbp);
4100 hbp = xlog_get_bp(log, hblks);
4101 } else {
4102 hblks = 1;
4103 }
4104 } else {
4105 ASSERT(log->l_sectBBsize == 1);
4106 hblks = 1;
4107 hbp = xlog_get_bp(log, 1);
4108 h_size = XLOG_BIG_RECORD_BSIZE;
4109 }
4110
4111 if (!hbp)
4112 return ENOMEM;
4113 dbp = xlog_get_bp(log, BTOBB(h_size));
4114 if (!dbp) {
4115 xlog_put_bp(hbp);
4116 return ENOMEM;
4117 }
4118
4119 memset(rhash, 0, sizeof(rhash));
4120 if (tail_blk <= head_blk) {
4121 for (blk_no = tail_blk; blk_no < head_blk; ) {
4122 error = xlog_bread(log, blk_no, hblks, hbp, &offset);
4123 if (error)
4124 goto bread_err2;
4125
4126 rhead = (xlog_rec_header_t *)offset;
4127 error = xlog_valid_rec_header(log, rhead, blk_no);
4128 if (error)
4129 goto bread_err2;
4130
4131 /* blocks in data section */
4132 bblks = (int)BTOBB(be32_to_cpu(rhead->h_len));
4133 error = xlog_bread(log, blk_no + hblks, bblks, dbp,
4134 &offset);
4135 if (error)
4136 goto bread_err2;
4137
4138 error = xlog_unpack_data(rhead, offset, log);
4139 if (error)
4140 goto bread_err2;
4141
4142 error = xlog_recover_process_data(log,
4143 rhash, rhead, offset, pass);
4144 if (error)
4145 goto bread_err2;
4146 blk_no += bblks + hblks;
4147 }
4148 } else {
4149 /*
4150 * Perform recovery around the end of the physical log.
4151 * When the head is not on the same cycle number as the tail,
4152 * we can't do a sequential recovery as above.
4153 */
4154 blk_no = tail_blk;
4155 while (blk_no < log->l_logBBsize) {
4156 /*
4157 * Check for header wrapping around physical end-of-log
4158 */
4159 offset = hbp->b_addr;
4160 split_hblks = 0;
4161 wrapped_hblks = 0;
4162 if (blk_no + hblks <= log->l_logBBsize) {
4163 /* Read header in one read */
4164 error = xlog_bread(log, blk_no, hblks, hbp,
4165 &offset);
4166 if (error)
4167 goto bread_err2;
4168 } else {
4169 /* This LR is split across physical log end */
4170 if (blk_no != log->l_logBBsize) {
4171 /* some data before physical log end */
4172 ASSERT(blk_no <= INT_MAX);
4173 split_hblks = log->l_logBBsize - (int)blk_no;
4174 ASSERT(split_hblks > 0);
4175 error = xlog_bread(log, blk_no,
4176 split_hblks, hbp,
4177 &offset);
4178 if (error)
4179 goto bread_err2;
4180 }
4181
4182 /*
4183 * Note: this black magic still works with
4184 * large sector sizes (non-512) only because:
4185 * - we increased the buffer size originally
4186 * by 1 sector giving us enough extra space
4187 * for the second read;
4188 * - the log start is guaranteed to be sector
4189 * aligned;
4190 * - we read the log end (LR header start)
4191 * _first_, then the log start (LR header end)
4192 * - order is important.
4193 */
4194 wrapped_hblks = hblks - split_hblks;
4195 error = xlog_bread_offset(log, 0,
4196 wrapped_hblks, hbp,
4197 offset + BBTOB(split_hblks));
4198 if (error)
4199 goto bread_err2;
4200 }
4201 rhead = (xlog_rec_header_t *)offset;
4202 error = xlog_valid_rec_header(log, rhead,
4203 split_hblks ? blk_no : 0);
4204 if (error)
4205 goto bread_err2;
4206
4207 bblks = (int)BTOBB(be32_to_cpu(rhead->h_len));
4208 blk_no += hblks;
4209
4210 /* Read in data for log record */
4211 if (blk_no + bblks <= log->l_logBBsize) {
4212 error = xlog_bread(log, blk_no, bblks, dbp,
4213 &offset);
4214 if (error)
4215 goto bread_err2;
4216 } else {
4217 /* This log record is split across the
4218 * physical end of log */
4219 offset = dbp->b_addr;
4220 split_bblks = 0;
4221 if (blk_no != log->l_logBBsize) {
4222 /* some data is before the physical
4223 * end of log */
4224 ASSERT(!wrapped_hblks);
4225 ASSERT(blk_no <= INT_MAX);
4226 split_bblks =
4227 log->l_logBBsize - (int)blk_no;
4228 ASSERT(split_bblks > 0);
4229 error = xlog_bread(log, blk_no,
4230 split_bblks, dbp,
4231 &offset);
4232 if (error)
4233 goto bread_err2;
4234 }
4235
4236 /*
4237 * Note: this black magic still works with
4238 * large sector sizes (non-512) only because:
4239 * - we increased the buffer size originally
4240 * by 1 sector giving us enough extra space
4241 * for the second read;
4242 * - the log start is guaranteed to be sector
4243 * aligned;
4244 * - we read the log end (LR header start)
4245 * _first_, then the log start (LR header end)
4246 * - order is important.
4247 */
4248 error = xlog_bread_offset(log, 0,
4249 bblks - split_bblks, dbp,
4250 offset + BBTOB(split_bblks));
4251 if (error)
4252 goto bread_err2;
4253 }
4254
4255 error = xlog_unpack_data(rhead, offset, log);
4256 if (error)
4257 goto bread_err2;
4258
4259 error = xlog_recover_process_data(log, rhash,
4260 rhead, offset, pass);
4261 if (error)
4262 goto bread_err2;
4263 blk_no += bblks;
4264 }
4265
4266 ASSERT(blk_no >= log->l_logBBsize);
4267 blk_no -= log->l_logBBsize;
4268
4269 /* read first part of physical log */
4270 while (blk_no < head_blk) {
4271 error = xlog_bread(log, blk_no, hblks, hbp, &offset);
4272 if (error)
4273 goto bread_err2;
4274
4275 rhead = (xlog_rec_header_t *)offset;
4276 error = xlog_valid_rec_header(log, rhead, blk_no);
4277 if (error)
4278 goto bread_err2;
4279
4280 bblks = (int)BTOBB(be32_to_cpu(rhead->h_len));
4281 error = xlog_bread(log, blk_no+hblks, bblks, dbp,
4282 &offset);
4283 if (error)
4284 goto bread_err2;
4285
4286 error = xlog_unpack_data(rhead, offset, log);
4287 if (error)
4288 goto bread_err2;
4289
4290 error = xlog_recover_process_data(log, rhash,
4291 rhead, offset, pass);
4292 if (error)
4293 goto bread_err2;
4294 blk_no += bblks + hblks;
4295 }
4296 }
4297
4298 bread_err2:
4299 xlog_put_bp(dbp);
4300 bread_err1:
4301 xlog_put_bp(hbp);
4302 return error;
4303}
4304
4305/*
4306 * Do the recovery of the log. We actually do this in two phases.
4307 * The two passes are necessary in order to implement the function
4308 * of cancelling a record written into the log. The first pass
4309 * determines those things which have been cancelled, and the
4310 * second pass replays log items normally except for those which
4311 * have been cancelled. The handling of the replay and cancellations
4312 * takes place in the log item type specific routines.
4313 *
4314 * The table of items which have cancel records in the log is allocated
4315 * and freed at this level, since only here do we know when all of
4316 * the log recovery has been completed.
4317 */
4318STATIC int
4319xlog_do_log_recovery(
4320 struct xlog *log,
4321 xfs_daddr_t head_blk,
4322 xfs_daddr_t tail_blk)
4323{
4324 int error, i;
4325
4326 ASSERT(head_blk != tail_blk);
4327
4328 /*
4329 * First do a pass to find all of the cancelled buf log items.
4330 * Store them in the buf_cancel_table for use in the second pass.
4331 */
4332 log->l_buf_cancel_table = kmem_zalloc(XLOG_BC_TABLE_SIZE *
4333 sizeof(struct list_head),
4334 KM_SLEEP);
4335 for (i = 0; i < XLOG_BC_TABLE_SIZE; i++)
4336 INIT_LIST_HEAD(&log->l_buf_cancel_table[i]);
4337
4338 error = xlog_do_recovery_pass(log, head_blk, tail_blk,
4339 XLOG_RECOVER_PASS1);
4340 if (error != 0) {
4341 kmem_free(log->l_buf_cancel_table);
4342 log->l_buf_cancel_table = NULL;
4343 return error;
4344 }
4345 /*
4346 * Then do a second pass to actually recover the items in the log.
4347 * When it is complete free the table of buf cancel items.
4348 */
4349 error = xlog_do_recovery_pass(log, head_blk, tail_blk,
4350 XLOG_RECOVER_PASS2);
4351#ifdef DEBUG
4352 if (!error) {
4353 int i;
4354
4355 for (i = 0; i < XLOG_BC_TABLE_SIZE; i++)
4356 ASSERT(list_empty(&log->l_buf_cancel_table[i]));
4357 }
4358#endif /* DEBUG */
4359
4360 kmem_free(log->l_buf_cancel_table);
4361 log->l_buf_cancel_table = NULL;
4362
4363 return error;
4364}
4365
4366/*
4367 * Do the actual recovery
4368 */
4369STATIC int
4370xlog_do_recover(
4371 struct xlog *log,
4372 xfs_daddr_t head_blk,
4373 xfs_daddr_t tail_blk)
4374{
4375 int error;
4376 xfs_buf_t *bp;
4377 xfs_sb_t *sbp;
4378
4379 /*
4380 * First replay the images in the log.
4381 */
4382 error = xlog_do_log_recovery(log, head_blk, tail_blk);
4383 if (error)
4384 return error;
4385
4386 /*
4387 * If IO errors happened during recovery, bail out.
4388 */
4389 if (XFS_FORCED_SHUTDOWN(log->l_mp)) {
4390 return (EIO);
4391 }
4392
4393 /*
4394 * We now update the tail_lsn since much of the recovery has completed
4395 * and there may be space available to use. If there were no extent
4396 * or iunlinks, we can free up the entire log and set the tail_lsn to
4397 * be the last_sync_lsn. This was set in xlog_find_tail to be the
4398 * lsn of the last known good LR on disk. If there are extent frees
4399 * or iunlinks they will have some entries in the AIL; so we look at
4400 * the AIL to determine how to set the tail_lsn.
4401 */
4402 xlog_assign_tail_lsn(log->l_mp);
4403
4404 /*
4405 * Now that we've finished replaying all buffer and inode
4406 * updates, re-read in the superblock and reverify it.
4407 */
4408 bp = xfs_getsb(log->l_mp, 0);
4409 XFS_BUF_UNDONE(bp);
4410 ASSERT(!(XFS_BUF_ISWRITE(bp)));
4411 XFS_BUF_READ(bp);
4412 XFS_BUF_UNASYNC(bp);
4413 bp->b_ops = &xfs_sb_buf_ops;
4414
4415 if (XFS_FORCED_SHUTDOWN(log->l_mp)) {
4416 xfs_buf_relse(bp);
4417 return XFS_ERROR(EIO);
4418 }
4419
4420 xfs_buf_iorequest(bp);
4421 error = xfs_buf_iowait(bp);
4422 if (error) {
4423 xfs_buf_ioerror_alert(bp, __func__);
4424 ASSERT(0);
4425 xfs_buf_relse(bp);
4426 return error;
4427 }
4428
4429 /* Convert superblock from on-disk format */
4430 sbp = &log->l_mp->m_sb;
4431 xfs_sb_from_disk(sbp, XFS_BUF_TO_SBP(bp));
4432 ASSERT(sbp->sb_magicnum == XFS_SB_MAGIC);
4433 ASSERT(xfs_sb_good_version(sbp));
4434 xfs_buf_relse(bp);
4435
4436 /* We've re-read the superblock so re-initialize per-cpu counters */
4437 xfs_icsb_reinit_counters(log->l_mp);
4438
4439 xlog_recover_check_summary(log);
4440
4441 /* Normal transactions can now occur */
4442 log->l_flags &= ~XLOG_ACTIVE_RECOVERY;
4443 return 0;
4444}
4445
4446/*
4447 * Perform recovery and re-initialize some log variables in xlog_find_tail.
4448 *
4449 * Return error or zero.
4450 */
4451int
4452xlog_recover(
4453 struct xlog *log)
4454{
4455 xfs_daddr_t head_blk, tail_blk;
4456 int error;
4457
4458 /* find the tail of the log */
4459 if ((error = xlog_find_tail(log, &head_blk, &tail_blk)))
4460 return error;
4461
4462 if (tail_blk != head_blk) {
4463 /* There used to be a comment here:
4464 *
4465 * disallow recovery on read-only mounts. note -- mount
4466 * checks for ENOSPC and turns it into an intelligent
4467 * error message.
4468 * ...but this is no longer true. Now, unless you specify
4469 * NORECOVERY (in which case this function would never be
4470 * called), we just go ahead and recover. We do this all
4471 * under the vfs layer, so we can get away with it unless
4472 * the device itself is read-only, in which case we fail.
4473 */
4474 if ((error = xfs_dev_is_read_only(log->l_mp, "recovery"))) {
4475 return error;
4476 }
4477
4478 /*
4479 * Version 5 superblock log feature mask validation. We know the
4480 * log is dirty so check if there are any unknown log features
4481 * in what we need to recover. If there are unknown features
4482 * (e.g. unsupported transactions, then simply reject the
4483 * attempt at recovery before touching anything.
4484 */
4485 if (XFS_SB_VERSION_NUM(&log->l_mp->m_sb) == XFS_SB_VERSION_5 &&
4486 xfs_sb_has_incompat_log_feature(&log->l_mp->m_sb,
4487 XFS_SB_FEAT_INCOMPAT_LOG_UNKNOWN)) {
4488 xfs_warn(log->l_mp,
4489"Superblock has unknown incompatible log features (0x%x) enabled.\n"
4490"The log can not be fully and/or safely recovered by this kernel.\n"
4491"Please recover the log on a kernel that supports the unknown features.",
4492 (log->l_mp->m_sb.sb_features_log_incompat &
4493 XFS_SB_FEAT_INCOMPAT_LOG_UNKNOWN));
4494 return EINVAL;
4495 }
4496
4497 xfs_notice(log->l_mp, "Starting recovery (logdev: %s)",
4498 log->l_mp->m_logname ? log->l_mp->m_logname
4499 : "internal");
4500
4501 error = xlog_do_recover(log, head_blk, tail_blk);
4502 log->l_flags |= XLOG_RECOVERY_NEEDED;
4503 }
4504 return error;
4505}
4506
4507/*
4508 * In the first part of recovery we replay inodes and buffers and build
4509 * up the list of extent free items which need to be processed. Here
4510 * we process the extent free items and clean up the on disk unlinked
4511 * inode lists. This is separated from the first part of recovery so
4512 * that the root and real-time bitmap inodes can be read in from disk in
4513 * between the two stages. This is necessary so that we can free space
4514 * in the real-time portion of the file system.
4515 */
4516int
4517xlog_recover_finish(
4518 struct xlog *log)
4519{
4520 /*
4521 * Now we're ready to do the transactions needed for the
4522 * rest of recovery. Start with completing all the extent
4523 * free intent records and then process the unlinked inode
4524 * lists. At this point, we essentially run in normal mode
4525 * except that we're still performing recovery actions
4526 * rather than accepting new requests.
4527 */
4528 if (log->l_flags & XLOG_RECOVERY_NEEDED) {
4529 int error;
4530 error = xlog_recover_process_efis(log);
4531 if (error) {
4532 xfs_alert(log->l_mp, "Failed to recover EFIs");
4533 return error;
4534 }
4535 /*
4536 * Sync the log to get all the EFIs out of the AIL.
4537 * This isn't absolutely necessary, but it helps in
4538 * case the unlink transactions would have problems
4539 * pushing the EFIs out of the way.
4540 */
4541 xfs_log_force(log->l_mp, XFS_LOG_SYNC);
4542
4543 xlog_recover_process_iunlinks(log);
4544
4545 xlog_recover_check_summary(log);
4546
4547 xfs_notice(log->l_mp, "Ending recovery (logdev: %s)",
4548 log->l_mp->m_logname ? log->l_mp->m_logname
4549 : "internal");
4550 log->l_flags &= ~XLOG_RECOVERY_NEEDED;
4551 } else {
4552 xfs_info(log->l_mp, "Ending clean mount");
4553 }
4554 return 0;
4555}
4556
4557
4558#if defined(DEBUG)
4559/*
4560 * Read all of the agf and agi counters and check that they
4561 * are consistent with the superblock counters.
4562 */
4563void
4564xlog_recover_check_summary(
4565 struct xlog *log)
4566{
4567 xfs_mount_t *mp;
4568 xfs_agf_t *agfp;
4569 xfs_buf_t *agfbp;
4570 xfs_buf_t *agibp;
4571 xfs_agnumber_t agno;
4572 __uint64_t freeblks;
4573 __uint64_t itotal;
4574 __uint64_t ifree;
4575 int error;
4576
4577 mp = log->l_mp;
4578
4579 freeblks = 0LL;
4580 itotal = 0LL;
4581 ifree = 0LL;
4582 for (agno = 0; agno < mp->m_sb.sb_agcount; agno++) {
4583 error = xfs_read_agf(mp, NULL, agno, 0, &agfbp);
4584 if (error) {
4585 xfs_alert(mp, "%s agf read failed agno %d error %d",
4586 __func__, agno, error);
4587 } else {
4588 agfp = XFS_BUF_TO_AGF(agfbp);
4589 freeblks += be32_to_cpu(agfp->agf_freeblks) +
4590 be32_to_cpu(agfp->agf_flcount);
4591 xfs_buf_relse(agfbp);
4592 }
4593
4594 error = xfs_read_agi(mp, NULL, agno, &agibp);
4595 if (error) {
4596 xfs_alert(mp, "%s agi read failed agno %d error %d",
4597 __func__, agno, error);
4598 } else {
4599 struct xfs_agi *agi = XFS_BUF_TO_AGI(agibp);
4600
4601 itotal += be32_to_cpu(agi->agi_count);
4602 ifree += be32_to_cpu(agi->agi_freecount);
4603 xfs_buf_relse(agibp);
4604 }
4605 }
4606}
4607#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 log->l_ailp->ail_head_lsn =
1181 atomic64_read(&log->l_tail_lsn);
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 log->l_ailp->ail_head_lsn = be64_to_cpu(rhead->h_lsn);
1216}
1217
1218/*
1219 * Find the sync block number or the tail of the log.
1220 *
1221 * This will be the block number of the last record to have its
1222 * associated buffers synced to disk. Every log record header has
1223 * a sync lsn embedded in it. LSNs hold block numbers, so it is easy
1224 * to get a sync block number. The only concern is to figure out which
1225 * log record header to believe.
1226 *
1227 * The following algorithm uses the log record header with the largest
1228 * lsn. The entire log record does not need to be valid. We only care
1229 * that the header is valid.
1230 *
1231 * We could speed up search by using current head_blk buffer, but it is not
1232 * available.
1233 */
1234STATIC int
1235xlog_find_tail(
1236 struct xlog *log,
1237 xfs_daddr_t *head_blk,
1238 xfs_daddr_t *tail_blk)
1239{
1240 xlog_rec_header_t *rhead;
1241 char *offset = NULL;
1242 char *buffer;
1243 int error;
1244 xfs_daddr_t rhead_blk;
1245 xfs_lsn_t tail_lsn;
1246 bool wrapped = false;
1247 bool clean = false;
1248
1249 /*
1250 * Find previous log record
1251 */
1252 if ((error = xlog_find_head(log, head_blk)))
1253 return error;
1254 ASSERT(*head_blk < INT_MAX);
1255
1256 buffer = xlog_alloc_buffer(log, 1);
1257 if (!buffer)
1258 return -ENOMEM;
1259 if (*head_blk == 0) { /* special case */
1260 error = xlog_bread(log, 0, 1, buffer, &offset);
1261 if (error)
1262 goto done;
1263
1264 if (xlog_get_cycle(offset) == 0) {
1265 *tail_blk = 0;
1266 /* leave all other log inited values alone */
1267 goto done;
1268 }
1269 }
1270
1271 /*
1272 * Search backwards through the log looking for the log record header
1273 * block. This wraps all the way back around to the head so something is
1274 * seriously wrong if we can't find it.
1275 */
1276 error = xlog_rseek_logrec_hdr(log, *head_blk, *head_blk, 1, buffer,
1277 &rhead_blk, &rhead, &wrapped);
1278 if (error < 0)
1279 goto done;
1280 if (!error) {
1281 xfs_warn(log->l_mp, "%s: couldn't find sync record", __func__);
1282 error = -EFSCORRUPTED;
1283 goto done;
1284 }
1285 *tail_blk = BLOCK_LSN(be64_to_cpu(rhead->h_tail_lsn));
1286
1287 /*
1288 * Set the log state based on the current head record.
1289 */
1290 xlog_set_state(log, *head_blk, rhead, rhead_blk, wrapped);
1291 tail_lsn = atomic64_read(&log->l_tail_lsn);
1292
1293 /*
1294 * Look for an unmount record at the head of the log. This sets the log
1295 * state to determine whether recovery is necessary.
1296 */
1297 error = xlog_check_unmount_rec(log, head_blk, tail_blk, rhead,
1298 rhead_blk, buffer, &clean);
1299 if (error)
1300 goto done;
1301
1302 /*
1303 * Verify the log head if the log is not clean (e.g., we have anything
1304 * but an unmount record at the head). This uses CRC verification to
1305 * detect and trim torn writes. If discovered, CRC failures are
1306 * considered torn writes and the log head is trimmed accordingly.
1307 *
1308 * Note that we can only run CRC verification when the log is dirty
1309 * because there's no guarantee that the log data behind an unmount
1310 * record is compatible with the current architecture.
1311 */
1312 if (!clean) {
1313 xfs_daddr_t orig_head = *head_blk;
1314
1315 error = xlog_verify_head(log, head_blk, tail_blk, buffer,
1316 &rhead_blk, &rhead, &wrapped);
1317 if (error)
1318 goto done;
1319
1320 /* update in-core state again if the head changed */
1321 if (*head_blk != orig_head) {
1322 xlog_set_state(log, *head_blk, rhead, rhead_blk,
1323 wrapped);
1324 tail_lsn = atomic64_read(&log->l_tail_lsn);
1325 error = xlog_check_unmount_rec(log, head_blk, tail_blk,
1326 rhead, rhead_blk, buffer,
1327 &clean);
1328 if (error)
1329 goto done;
1330 }
1331 }
1332
1333 /*
1334 * Note that the unmount was clean. If the unmount was not clean, we
1335 * need to know this to rebuild the superblock counters from the perag
1336 * headers if we have a filesystem using non-persistent counters.
1337 */
1338 if (clean)
1339 xfs_set_clean(log->l_mp);
1340
1341 /*
1342 * Make sure that there are no blocks in front of the head
1343 * with the same cycle number as the head. This can happen
1344 * because we allow multiple outstanding log writes concurrently,
1345 * and the later writes might make it out before earlier ones.
1346 *
1347 * We use the lsn from before modifying it so that we'll never
1348 * overwrite the unmount record after a clean unmount.
1349 *
1350 * Do this only if we are going to recover the filesystem
1351 *
1352 * NOTE: This used to say "if (!readonly)"
1353 * However on Linux, we can & do recover a read-only filesystem.
1354 * We only skip recovery if NORECOVERY is specified on mount,
1355 * in which case we would not be here.
1356 *
1357 * But... if the -device- itself is readonly, just skip this.
1358 * We can't recover this device anyway, so it won't matter.
1359 */
1360 if (!xfs_readonly_buftarg(log->l_targ))
1361 error = xlog_clear_stale_blocks(log, tail_lsn);
1362
1363done:
1364 kvfree(buffer);
1365
1366 if (error)
1367 xfs_warn(log->l_mp, "failed to locate log tail");
1368 return error;
1369}
1370
1371/*
1372 * Is the log zeroed at all?
1373 *
1374 * The last binary search should be changed to perform an X block read
1375 * once X becomes small enough. You can then search linearly through
1376 * the X blocks. This will cut down on the number of reads we need to do.
1377 *
1378 * If the log is partially zeroed, this routine will pass back the blkno
1379 * of the first block with cycle number 0. It won't have a complete LR
1380 * preceding it.
1381 *
1382 * Return:
1383 * 0 => the log is completely written to
1384 * 1 => use *blk_no as the first block of the log
1385 * <0 => error has occurred
1386 */
1387STATIC int
1388xlog_find_zeroed(
1389 struct xlog *log,
1390 xfs_daddr_t *blk_no)
1391{
1392 char *buffer;
1393 char *offset;
1394 uint first_cycle, last_cycle;
1395 xfs_daddr_t new_blk, last_blk, start_blk;
1396 xfs_daddr_t num_scan_bblks;
1397 int error, log_bbnum = log->l_logBBsize;
1398 int ret = 1;
1399
1400 *blk_no = 0;
1401
1402 /* check totally zeroed log */
1403 buffer = xlog_alloc_buffer(log, 1);
1404 if (!buffer)
1405 return -ENOMEM;
1406 error = xlog_bread(log, 0, 1, buffer, &offset);
1407 if (error)
1408 goto out_free_buffer;
1409
1410 first_cycle = xlog_get_cycle(offset);
1411 if (first_cycle == 0) { /* completely zeroed log */
1412 *blk_no = 0;
1413 goto out_free_buffer;
1414 }
1415
1416 /* check partially zeroed log */
1417 error = xlog_bread(log, log_bbnum-1, 1, buffer, &offset);
1418 if (error)
1419 goto out_free_buffer;
1420
1421 last_cycle = xlog_get_cycle(offset);
1422 if (last_cycle != 0) { /* log completely written to */
1423 ret = 0;
1424 goto out_free_buffer;
1425 }
1426
1427 /* we have a partially zeroed log */
1428 last_blk = log_bbnum-1;
1429 error = xlog_find_cycle_start(log, buffer, 0, &last_blk, 0);
1430 if (error)
1431 goto out_free_buffer;
1432
1433 /*
1434 * Validate the answer. Because there is no way to guarantee that
1435 * the entire log is made up of log records which are the same size,
1436 * we scan over the defined maximum blocks. At this point, the maximum
1437 * is not chosen to mean anything special. XXXmiken
1438 */
1439 num_scan_bblks = XLOG_TOTAL_REC_SHIFT(log);
1440 ASSERT(num_scan_bblks <= INT_MAX);
1441
1442 if (last_blk < num_scan_bblks)
1443 num_scan_bblks = last_blk;
1444 start_blk = last_blk - num_scan_bblks;
1445
1446 /*
1447 * We search for any instances of cycle number 0 that occur before
1448 * our current estimate of the head. What we're trying to detect is
1449 * 1 ... | 0 | 1 | 0...
1450 * ^ binary search ends here
1451 */
1452 if ((error = xlog_find_verify_cycle(log, start_blk,
1453 (int)num_scan_bblks, 0, &new_blk)))
1454 goto out_free_buffer;
1455 if (new_blk != -1)
1456 last_blk = new_blk;
1457
1458 /*
1459 * Potentially backup over partial log record write. We don't need
1460 * to search the end of the log because we know it is zero.
1461 */
1462 error = xlog_find_verify_log_record(log, start_blk, &last_blk, 0);
1463 if (error == 1)
1464 error = -EIO;
1465 if (error)
1466 goto out_free_buffer;
1467
1468 *blk_no = last_blk;
1469out_free_buffer:
1470 kvfree(buffer);
1471 if (error)
1472 return error;
1473 return ret;
1474}
1475
1476/*
1477 * These are simple subroutines used by xlog_clear_stale_blocks() below
1478 * to initialize a buffer full of empty log record headers and write
1479 * them into the log.
1480 */
1481STATIC void
1482xlog_add_record(
1483 struct xlog *log,
1484 char *buf,
1485 int cycle,
1486 int block,
1487 int tail_cycle,
1488 int tail_block)
1489{
1490 xlog_rec_header_t *recp = (xlog_rec_header_t *)buf;
1491
1492 memset(buf, 0, BBSIZE);
1493 recp->h_magicno = cpu_to_be32(XLOG_HEADER_MAGIC_NUM);
1494 recp->h_cycle = cpu_to_be32(cycle);
1495 recp->h_version = cpu_to_be32(
1496 xfs_has_logv2(log->l_mp) ? 2 : 1);
1497 recp->h_lsn = cpu_to_be64(xlog_assign_lsn(cycle, block));
1498 recp->h_tail_lsn = cpu_to_be64(xlog_assign_lsn(tail_cycle, tail_block));
1499 recp->h_fmt = cpu_to_be32(XLOG_FMT);
1500 memcpy(&recp->h_fs_uuid, &log->l_mp->m_sb.sb_uuid, sizeof(uuid_t));
1501}
1502
1503STATIC int
1504xlog_write_log_records(
1505 struct xlog *log,
1506 int cycle,
1507 int start_block,
1508 int blocks,
1509 int tail_cycle,
1510 int tail_block)
1511{
1512 char *offset;
1513 char *buffer;
1514 int balign, ealign;
1515 int sectbb = log->l_sectBBsize;
1516 int end_block = start_block + blocks;
1517 int bufblks;
1518 int error = 0;
1519 int i, j = 0;
1520
1521 /*
1522 * Greedily allocate a buffer big enough to handle the full
1523 * range of basic blocks to be written. If that fails, try
1524 * a smaller size. We need to be able to write at least a
1525 * log sector, or we're out of luck.
1526 */
1527 bufblks = roundup_pow_of_two(blocks);
1528 while (bufblks > log->l_logBBsize)
1529 bufblks >>= 1;
1530 while (!(buffer = xlog_alloc_buffer(log, bufblks))) {
1531 bufblks >>= 1;
1532 if (bufblks < sectbb)
1533 return -ENOMEM;
1534 }
1535
1536 /* We may need to do a read at the start to fill in part of
1537 * the buffer in the starting sector not covered by the first
1538 * write below.
1539 */
1540 balign = round_down(start_block, sectbb);
1541 if (balign != start_block) {
1542 error = xlog_bread_noalign(log, start_block, 1, buffer);
1543 if (error)
1544 goto out_free_buffer;
1545
1546 j = start_block - balign;
1547 }
1548
1549 for (i = start_block; i < end_block; i += bufblks) {
1550 int bcount, endcount;
1551
1552 bcount = min(bufblks, end_block - start_block);
1553 endcount = bcount - j;
1554
1555 /* We may need to do a read at the end to fill in part of
1556 * the buffer in the final sector not covered by the write.
1557 * If this is the same sector as the above read, skip it.
1558 */
1559 ealign = round_down(end_block, sectbb);
1560 if (j == 0 && (start_block + endcount > ealign)) {
1561 error = xlog_bread_noalign(log, ealign, sectbb,
1562 buffer + BBTOB(ealign - start_block));
1563 if (error)
1564 break;
1565
1566 }
1567
1568 offset = buffer + xlog_align(log, start_block);
1569 for (; j < endcount; j++) {
1570 xlog_add_record(log, offset, cycle, i+j,
1571 tail_cycle, tail_block);
1572 offset += BBSIZE;
1573 }
1574 error = xlog_bwrite(log, start_block, endcount, buffer);
1575 if (error)
1576 break;
1577 start_block += endcount;
1578 j = 0;
1579 }
1580
1581out_free_buffer:
1582 kvfree(buffer);
1583 return error;
1584}
1585
1586/*
1587 * This routine is called to blow away any incomplete log writes out
1588 * in front of the log head. We do this so that we won't become confused
1589 * if we come up, write only a little bit more, and then crash again.
1590 * If we leave the partial log records out there, this situation could
1591 * cause us to think those partial writes are valid blocks since they
1592 * have the current cycle number. We get rid of them by overwriting them
1593 * with empty log records with the old cycle number rather than the
1594 * current one.
1595 *
1596 * The tail lsn is passed in rather than taken from
1597 * the log so that we will not write over the unmount record after a
1598 * clean unmount in a 512 block log. Doing so would leave the log without
1599 * any valid log records in it until a new one was written. If we crashed
1600 * during that time we would not be able to recover.
1601 */
1602STATIC int
1603xlog_clear_stale_blocks(
1604 struct xlog *log,
1605 xfs_lsn_t tail_lsn)
1606{
1607 int tail_cycle, head_cycle;
1608 int tail_block, head_block;
1609 int tail_distance, max_distance;
1610 int distance;
1611 int error;
1612
1613 tail_cycle = CYCLE_LSN(tail_lsn);
1614 tail_block = BLOCK_LSN(tail_lsn);
1615 head_cycle = log->l_curr_cycle;
1616 head_block = log->l_curr_block;
1617
1618 /*
1619 * Figure out the distance between the new head of the log
1620 * and the tail. We want to write over any blocks beyond the
1621 * head that we may have written just before the crash, but
1622 * we don't want to overwrite the tail of the log.
1623 */
1624 if (head_cycle == tail_cycle) {
1625 /*
1626 * The tail is behind the head in the physical log,
1627 * so the distance from the head to the tail is the
1628 * distance from the head to the end of the log plus
1629 * the distance from the beginning of the log to the
1630 * tail.
1631 */
1632 if (XFS_IS_CORRUPT(log->l_mp,
1633 head_block < tail_block ||
1634 head_block >= log->l_logBBsize))
1635 return -EFSCORRUPTED;
1636 tail_distance = tail_block + (log->l_logBBsize - head_block);
1637 } else {
1638 /*
1639 * The head is behind the tail in the physical log,
1640 * so the distance from the head to the tail is just
1641 * the tail block minus the head block.
1642 */
1643 if (XFS_IS_CORRUPT(log->l_mp,
1644 head_block >= tail_block ||
1645 head_cycle != tail_cycle + 1))
1646 return -EFSCORRUPTED;
1647 tail_distance = tail_block - head_block;
1648 }
1649
1650 /*
1651 * If the head is right up against the tail, we can't clear
1652 * anything.
1653 */
1654 if (tail_distance <= 0) {
1655 ASSERT(tail_distance == 0);
1656 return 0;
1657 }
1658
1659 max_distance = XLOG_TOTAL_REC_SHIFT(log);
1660 /*
1661 * Take the smaller of the maximum amount of outstanding I/O
1662 * we could have and the distance to the tail to clear out.
1663 * We take the smaller so that we don't overwrite the tail and
1664 * we don't waste all day writing from the head to the tail
1665 * for no reason.
1666 */
1667 max_distance = min(max_distance, tail_distance);
1668
1669 if ((head_block + max_distance) <= log->l_logBBsize) {
1670 /*
1671 * We can stomp all the blocks we need to without
1672 * wrapping around the end of the log. Just do it
1673 * in a single write. Use the cycle number of the
1674 * current cycle minus one so that the log will look like:
1675 * n ... | n - 1 ...
1676 */
1677 error = xlog_write_log_records(log, (head_cycle - 1),
1678 head_block, max_distance, tail_cycle,
1679 tail_block);
1680 if (error)
1681 return error;
1682 } else {
1683 /*
1684 * We need to wrap around the end of the physical log in
1685 * order to clear all the blocks. Do it in two separate
1686 * I/Os. The first write should be from the head to the
1687 * end of the physical log, and it should use the current
1688 * cycle number minus one just like above.
1689 */
1690 distance = log->l_logBBsize - head_block;
1691 error = xlog_write_log_records(log, (head_cycle - 1),
1692 head_block, distance, tail_cycle,
1693 tail_block);
1694
1695 if (error)
1696 return error;
1697
1698 /*
1699 * Now write the blocks at the start of the physical log.
1700 * This writes the remainder of the blocks we want to clear.
1701 * It uses the current cycle number since we're now on the
1702 * same cycle as the head so that we get:
1703 * n ... n ... | n - 1 ...
1704 * ^^^^^ blocks we're writing
1705 */
1706 distance = max_distance - (log->l_logBBsize - head_block);
1707 error = xlog_write_log_records(log, head_cycle, 0, distance,
1708 tail_cycle, tail_block);
1709 if (error)
1710 return error;
1711 }
1712
1713 return 0;
1714}
1715
1716/*
1717 * Release the recovered intent item in the AIL that matches the given intent
1718 * type and intent id.
1719 */
1720void
1721xlog_recover_release_intent(
1722 struct xlog *log,
1723 unsigned short intent_type,
1724 uint64_t intent_id)
1725{
1726 struct xfs_defer_pending *dfp, *n;
1727
1728 list_for_each_entry_safe(dfp, n, &log->r_dfops, dfp_list) {
1729 struct xfs_log_item *lip = dfp->dfp_intent;
1730
1731 if (lip->li_type != intent_type)
1732 continue;
1733 if (!lip->li_ops->iop_match(lip, intent_id))
1734 continue;
1735
1736 ASSERT(xlog_item_is_intent(lip));
1737
1738 xfs_defer_cancel_recovery(log->l_mp, dfp);
1739 }
1740}
1741
1742int
1743xlog_recover_iget(
1744 struct xfs_mount *mp,
1745 xfs_ino_t ino,
1746 struct xfs_inode **ipp)
1747{
1748 int error;
1749
1750 error = xfs_iget(mp, NULL, ino, 0, 0, ipp);
1751 if (error)
1752 return error;
1753
1754 error = xfs_qm_dqattach(*ipp);
1755 if (error) {
1756 xfs_irele(*ipp);
1757 return error;
1758 }
1759
1760 if (VFS_I(*ipp)->i_nlink == 0)
1761 xfs_iflags_set(*ipp, XFS_IRECOVERY);
1762
1763 return 0;
1764}
1765
1766/*
1767 * Get an inode so that we can recover a log operation.
1768 *
1769 * Log intent items that target inodes effectively contain a file handle.
1770 * Check that the generation number matches the intent item like we do for
1771 * other file handles. Log intent items defined after this validation weakness
1772 * was identified must use this function.
1773 */
1774int
1775xlog_recover_iget_handle(
1776 struct xfs_mount *mp,
1777 xfs_ino_t ino,
1778 uint32_t gen,
1779 struct xfs_inode **ipp)
1780{
1781 struct xfs_inode *ip;
1782 int error;
1783
1784 error = xlog_recover_iget(mp, ino, &ip);
1785 if (error)
1786 return error;
1787
1788 if (VFS_I(ip)->i_generation != gen) {
1789 xfs_irele(ip);
1790 return -EFSCORRUPTED;
1791 }
1792
1793 *ipp = ip;
1794 return 0;
1795}
1796
1797/******************************************************************************
1798 *
1799 * Log recover routines
1800 *
1801 ******************************************************************************
1802 */
1803static const struct xlog_recover_item_ops *xlog_recover_item_ops[] = {
1804 &xlog_buf_item_ops,
1805 &xlog_inode_item_ops,
1806 &xlog_dquot_item_ops,
1807 &xlog_quotaoff_item_ops,
1808 &xlog_icreate_item_ops,
1809 &xlog_efi_item_ops,
1810 &xlog_efd_item_ops,
1811 &xlog_rui_item_ops,
1812 &xlog_rud_item_ops,
1813 &xlog_cui_item_ops,
1814 &xlog_cud_item_ops,
1815 &xlog_bui_item_ops,
1816 &xlog_bud_item_ops,
1817 &xlog_attri_item_ops,
1818 &xlog_attrd_item_ops,
1819 &xlog_xmi_item_ops,
1820 &xlog_xmd_item_ops,
1821 &xlog_rtefi_item_ops,
1822 &xlog_rtefd_item_ops,
1823};
1824
1825static const struct xlog_recover_item_ops *
1826xlog_find_item_ops(
1827 struct xlog_recover_item *item)
1828{
1829 unsigned int i;
1830
1831 for (i = 0; i < ARRAY_SIZE(xlog_recover_item_ops); i++)
1832 if (ITEM_TYPE(item) == xlog_recover_item_ops[i]->item_type)
1833 return xlog_recover_item_ops[i];
1834
1835 return NULL;
1836}
1837
1838/*
1839 * Sort the log items in the transaction.
1840 *
1841 * The ordering constraints are defined by the inode allocation and unlink
1842 * behaviour. The rules are:
1843 *
1844 * 1. Every item is only logged once in a given transaction. Hence it
1845 * represents the last logged state of the item. Hence ordering is
1846 * dependent on the order in which operations need to be performed so
1847 * required initial conditions are always met.
1848 *
1849 * 2. Cancelled buffers are recorded in pass 1 in a separate table and
1850 * there's nothing to replay from them so we can simply cull them
1851 * from the transaction. However, we can't do that until after we've
1852 * replayed all the other items because they may be dependent on the
1853 * cancelled buffer and replaying the cancelled buffer can remove it
1854 * form the cancelled buffer table. Hence they have to be done last.
1855 *
1856 * 3. Inode allocation buffers must be replayed before inode items that
1857 * read the buffer and replay changes into it. For filesystems using the
1858 * ICREATE transactions, this means XFS_LI_ICREATE objects need to get
1859 * treated the same as inode allocation buffers as they create and
1860 * initialise the buffers directly.
1861 *
1862 * 4. Inode unlink buffers must be replayed after inode items are replayed.
1863 * This ensures that inodes are completely flushed to the inode buffer
1864 * in a "free" state before we remove the unlinked inode list pointer.
1865 *
1866 * Hence the ordering needs to be inode allocation buffers first, inode items
1867 * second, inode unlink buffers third and cancelled buffers last.
1868 *
1869 * But there's a problem with that - we can't tell an inode allocation buffer
1870 * apart from a regular buffer, so we can't separate them. We can, however,
1871 * tell an inode unlink buffer from the others, and so we can separate them out
1872 * from all the other buffers and move them to last.
1873 *
1874 * Hence, 4 lists, in order from head to tail:
1875 * - buffer_list for all buffers except cancelled/inode unlink buffers
1876 * - item_list for all non-buffer items
1877 * - inode_buffer_list for inode unlink buffers
1878 * - cancel_list for the cancelled buffers
1879 *
1880 * Note that we add objects to the tail of the lists so that first-to-last
1881 * ordering is preserved within the lists. Adding objects to the head of the
1882 * list means when we traverse from the head we walk them in last-to-first
1883 * order. For cancelled buffers and inode unlink buffers this doesn't matter,
1884 * but for all other items there may be specific ordering that we need to
1885 * preserve.
1886 */
1887STATIC int
1888xlog_recover_reorder_trans(
1889 struct xlog *log,
1890 struct xlog_recover *trans,
1891 int pass)
1892{
1893 struct xlog_recover_item *item, *n;
1894 int error = 0;
1895 LIST_HEAD(sort_list);
1896 LIST_HEAD(cancel_list);
1897 LIST_HEAD(buffer_list);
1898 LIST_HEAD(inode_buffer_list);
1899 LIST_HEAD(item_list);
1900
1901 list_splice_init(&trans->r_itemq, &sort_list);
1902 list_for_each_entry_safe(item, n, &sort_list, ri_list) {
1903 enum xlog_recover_reorder fate = XLOG_REORDER_ITEM_LIST;
1904
1905 item->ri_ops = xlog_find_item_ops(item);
1906 if (!item->ri_ops) {
1907 xfs_warn(log->l_mp,
1908 "%s: unrecognized type of log operation (%d)",
1909 __func__, ITEM_TYPE(item));
1910 ASSERT(0);
1911 /*
1912 * return the remaining items back to the transaction
1913 * item list so they can be freed in caller.
1914 */
1915 if (!list_empty(&sort_list))
1916 list_splice_init(&sort_list, &trans->r_itemq);
1917 error = -EFSCORRUPTED;
1918 break;
1919 }
1920
1921 if (item->ri_ops->reorder)
1922 fate = item->ri_ops->reorder(item);
1923
1924 switch (fate) {
1925 case XLOG_REORDER_BUFFER_LIST:
1926 list_move_tail(&item->ri_list, &buffer_list);
1927 break;
1928 case XLOG_REORDER_CANCEL_LIST:
1929 trace_xfs_log_recover_item_reorder_head(log,
1930 trans, item, pass);
1931 list_move(&item->ri_list, &cancel_list);
1932 break;
1933 case XLOG_REORDER_INODE_BUFFER_LIST:
1934 list_move(&item->ri_list, &inode_buffer_list);
1935 break;
1936 case XLOG_REORDER_ITEM_LIST:
1937 trace_xfs_log_recover_item_reorder_tail(log,
1938 trans, item, pass);
1939 list_move_tail(&item->ri_list, &item_list);
1940 break;
1941 }
1942 }
1943
1944 ASSERT(list_empty(&sort_list));
1945 if (!list_empty(&buffer_list))
1946 list_splice(&buffer_list, &trans->r_itemq);
1947 if (!list_empty(&item_list))
1948 list_splice_tail(&item_list, &trans->r_itemq);
1949 if (!list_empty(&inode_buffer_list))
1950 list_splice_tail(&inode_buffer_list, &trans->r_itemq);
1951 if (!list_empty(&cancel_list))
1952 list_splice_tail(&cancel_list, &trans->r_itemq);
1953 return error;
1954}
1955
1956void
1957xlog_buf_readahead(
1958 struct xlog *log,
1959 xfs_daddr_t blkno,
1960 uint len,
1961 const struct xfs_buf_ops *ops)
1962{
1963 if (!xlog_is_buffer_cancelled(log, blkno, len))
1964 xfs_buf_readahead(log->l_mp->m_ddev_targp, blkno, len, ops);
1965}
1966
1967/*
1968 * Create a deferred work structure for resuming and tracking the progress of a
1969 * log intent item that was found during recovery.
1970 */
1971void
1972xlog_recover_intent_item(
1973 struct xlog *log,
1974 struct xfs_log_item *lip,
1975 xfs_lsn_t lsn,
1976 const struct xfs_defer_op_type *ops)
1977{
1978 ASSERT(xlog_item_is_intent(lip));
1979
1980 xfs_defer_start_recovery(lip, &log->r_dfops, ops);
1981
1982 /*
1983 * Insert the intent into the AIL directly and drop one reference so
1984 * that finishing or canceling the work will drop the other.
1985 */
1986 xfs_trans_ail_insert(log->l_ailp, lip, lsn);
1987 lip->li_ops->iop_unpin(lip, 0);
1988}
1989
1990STATIC int
1991xlog_recover_items_pass2(
1992 struct xlog *log,
1993 struct xlog_recover *trans,
1994 struct list_head *buffer_list,
1995 struct list_head *item_list)
1996{
1997 struct xlog_recover_item *item;
1998 int error = 0;
1999
2000 list_for_each_entry(item, item_list, ri_list) {
2001 trace_xfs_log_recover_item_recover(log, trans, item,
2002 XLOG_RECOVER_PASS2);
2003
2004 if (item->ri_ops->commit_pass2)
2005 error = item->ri_ops->commit_pass2(log, buffer_list,
2006 item, trans->r_lsn);
2007 if (error)
2008 return error;
2009 }
2010
2011 return error;
2012}
2013
2014/*
2015 * Perform the transaction.
2016 *
2017 * If the transaction modifies a buffer or inode, do it now. Otherwise,
2018 * EFIs and EFDs get queued up by adding entries into the AIL for them.
2019 */
2020STATIC int
2021xlog_recover_commit_trans(
2022 struct xlog *log,
2023 struct xlog_recover *trans,
2024 int pass,
2025 struct list_head *buffer_list)
2026{
2027 int error = 0;
2028 int items_queued = 0;
2029 struct xlog_recover_item *item;
2030 struct xlog_recover_item *next;
2031 LIST_HEAD (ra_list);
2032 LIST_HEAD (done_list);
2033
2034 #define XLOG_RECOVER_COMMIT_QUEUE_MAX 100
2035
2036 hlist_del_init(&trans->r_list);
2037
2038 error = xlog_recover_reorder_trans(log, trans, pass);
2039 if (error)
2040 return error;
2041
2042 list_for_each_entry_safe(item, next, &trans->r_itemq, ri_list) {
2043 trace_xfs_log_recover_item_recover(log, trans, item, pass);
2044
2045 switch (pass) {
2046 case XLOG_RECOVER_PASS1:
2047 if (item->ri_ops->commit_pass1)
2048 error = item->ri_ops->commit_pass1(log, item);
2049 break;
2050 case XLOG_RECOVER_PASS2:
2051 if (item->ri_ops->ra_pass2)
2052 item->ri_ops->ra_pass2(log, item);
2053 list_move_tail(&item->ri_list, &ra_list);
2054 items_queued++;
2055 if (items_queued >= XLOG_RECOVER_COMMIT_QUEUE_MAX) {
2056 error = xlog_recover_items_pass2(log, trans,
2057 buffer_list, &ra_list);
2058 list_splice_tail_init(&ra_list, &done_list);
2059 items_queued = 0;
2060 }
2061
2062 break;
2063 default:
2064 ASSERT(0);
2065 }
2066
2067 if (error)
2068 goto out;
2069 }
2070
2071out:
2072 if (!list_empty(&ra_list)) {
2073 if (!error)
2074 error = xlog_recover_items_pass2(log, trans,
2075 buffer_list, &ra_list);
2076 list_splice_tail_init(&ra_list, &done_list);
2077 }
2078
2079 if (!list_empty(&done_list))
2080 list_splice_init(&done_list, &trans->r_itemq);
2081
2082 return error;
2083}
2084
2085STATIC void
2086xlog_recover_add_item(
2087 struct list_head *head)
2088{
2089 struct xlog_recover_item *item;
2090
2091 item = kzalloc(sizeof(struct xlog_recover_item),
2092 GFP_KERNEL | __GFP_NOFAIL);
2093 INIT_LIST_HEAD(&item->ri_list);
2094 list_add_tail(&item->ri_list, head);
2095}
2096
2097STATIC int
2098xlog_recover_add_to_cont_trans(
2099 struct xlog *log,
2100 struct xlog_recover *trans,
2101 char *dp,
2102 int len)
2103{
2104 struct xlog_recover_item *item;
2105 char *ptr, *old_ptr;
2106 int old_len;
2107
2108 /*
2109 * If the transaction is empty, the header was split across this and the
2110 * previous record. Copy the rest of the header.
2111 */
2112 if (list_empty(&trans->r_itemq)) {
2113 ASSERT(len <= sizeof(struct xfs_trans_header));
2114 if (len > sizeof(struct xfs_trans_header)) {
2115 xfs_warn(log->l_mp, "%s: bad header length", __func__);
2116 return -EFSCORRUPTED;
2117 }
2118
2119 xlog_recover_add_item(&trans->r_itemq);
2120 ptr = (char *)&trans->r_theader +
2121 sizeof(struct xfs_trans_header) - len;
2122 memcpy(ptr, dp, len);
2123 return 0;
2124 }
2125
2126 /* take the tail entry */
2127 item = list_entry(trans->r_itemq.prev, struct xlog_recover_item,
2128 ri_list);
2129
2130 old_ptr = item->ri_buf[item->ri_cnt-1].i_addr;
2131 old_len = item->ri_buf[item->ri_cnt-1].i_len;
2132
2133 ptr = kvrealloc(old_ptr, len + old_len, GFP_KERNEL);
2134 if (!ptr)
2135 return -ENOMEM;
2136 memcpy(&ptr[old_len], dp, len);
2137 item->ri_buf[item->ri_cnt-1].i_len += len;
2138 item->ri_buf[item->ri_cnt-1].i_addr = ptr;
2139 trace_xfs_log_recover_item_add_cont(log, trans, item, 0);
2140 return 0;
2141}
2142
2143/*
2144 * The next region to add is the start of a new region. It could be
2145 * a whole region or it could be the first part of a new region. Because
2146 * of this, the assumption here is that the type and size fields of all
2147 * format structures fit into the first 32 bits of the structure.
2148 *
2149 * This works because all regions must be 32 bit aligned. Therefore, we
2150 * either have both fields or we have neither field. In the case we have
2151 * neither field, the data part of the region is zero length. We only have
2152 * a log_op_header and can throw away the header since a new one will appear
2153 * later. If we have at least 4 bytes, then we can determine how many regions
2154 * will appear in the current log item.
2155 */
2156STATIC int
2157xlog_recover_add_to_trans(
2158 struct xlog *log,
2159 struct xlog_recover *trans,
2160 char *dp,
2161 int len)
2162{
2163 struct xfs_inode_log_format *in_f; /* any will do */
2164 struct xlog_recover_item *item;
2165 char *ptr;
2166
2167 if (!len)
2168 return 0;
2169 if (list_empty(&trans->r_itemq)) {
2170 /* we need to catch log corruptions here */
2171 if (*(uint *)dp != XFS_TRANS_HEADER_MAGIC) {
2172 xfs_warn(log->l_mp, "%s: bad header magic number",
2173 __func__);
2174 ASSERT(0);
2175 return -EFSCORRUPTED;
2176 }
2177
2178 if (len > sizeof(struct xfs_trans_header)) {
2179 xfs_warn(log->l_mp, "%s: bad header length", __func__);
2180 ASSERT(0);
2181 return -EFSCORRUPTED;
2182 }
2183
2184 /*
2185 * The transaction header can be arbitrarily split across op
2186 * records. If we don't have the whole thing here, copy what we
2187 * do have and handle the rest in the next record.
2188 */
2189 if (len == sizeof(struct xfs_trans_header))
2190 xlog_recover_add_item(&trans->r_itemq);
2191 memcpy(&trans->r_theader, dp, len);
2192 return 0;
2193 }
2194
2195 ptr = xlog_kvmalloc(len);
2196 memcpy(ptr, dp, len);
2197 in_f = (struct xfs_inode_log_format *)ptr;
2198
2199 /* take the tail entry */
2200 item = list_entry(trans->r_itemq.prev, struct xlog_recover_item,
2201 ri_list);
2202 if (item->ri_total != 0 &&
2203 item->ri_total == item->ri_cnt) {
2204 /* tail item is in use, get a new one */
2205 xlog_recover_add_item(&trans->r_itemq);
2206 item = list_entry(trans->r_itemq.prev,
2207 struct xlog_recover_item, ri_list);
2208 }
2209
2210 if (item->ri_total == 0) { /* first region to be added */
2211 if (in_f->ilf_size == 0 ||
2212 in_f->ilf_size > XLOG_MAX_REGIONS_IN_ITEM) {
2213 xfs_warn(log->l_mp,
2214 "bad number of regions (%d) in inode log format",
2215 in_f->ilf_size);
2216 ASSERT(0);
2217 kvfree(ptr);
2218 return -EFSCORRUPTED;
2219 }
2220
2221 item->ri_total = in_f->ilf_size;
2222 item->ri_buf = kzalloc(item->ri_total * sizeof(xfs_log_iovec_t),
2223 GFP_KERNEL | __GFP_NOFAIL);
2224 }
2225
2226 if (item->ri_total <= item->ri_cnt) {
2227 xfs_warn(log->l_mp,
2228 "log item region count (%d) overflowed size (%d)",
2229 item->ri_cnt, item->ri_total);
2230 ASSERT(0);
2231 kvfree(ptr);
2232 return -EFSCORRUPTED;
2233 }
2234
2235 /* Description region is ri_buf[0] */
2236 item->ri_buf[item->ri_cnt].i_addr = ptr;
2237 item->ri_buf[item->ri_cnt].i_len = len;
2238 item->ri_cnt++;
2239 trace_xfs_log_recover_item_add(log, trans, item, 0);
2240 return 0;
2241}
2242
2243/*
2244 * Free up any resources allocated by the transaction
2245 *
2246 * Remember that EFIs, EFDs, and IUNLINKs are handled later.
2247 */
2248STATIC void
2249xlog_recover_free_trans(
2250 struct xlog_recover *trans)
2251{
2252 struct xlog_recover_item *item, *n;
2253 int i;
2254
2255 hlist_del_init(&trans->r_list);
2256
2257 list_for_each_entry_safe(item, n, &trans->r_itemq, ri_list) {
2258 /* Free the regions in the item. */
2259 list_del(&item->ri_list);
2260 for (i = 0; i < item->ri_cnt; i++)
2261 kvfree(item->ri_buf[i].i_addr);
2262 /* Free the item itself */
2263 kfree(item->ri_buf);
2264 kfree(item);
2265 }
2266 /* Free the transaction recover structure */
2267 kfree(trans);
2268}
2269
2270/*
2271 * On error or completion, trans is freed.
2272 */
2273STATIC int
2274xlog_recovery_process_trans(
2275 struct xlog *log,
2276 struct xlog_recover *trans,
2277 char *dp,
2278 unsigned int len,
2279 unsigned int flags,
2280 int pass,
2281 struct list_head *buffer_list)
2282{
2283 int error = 0;
2284 bool freeit = false;
2285
2286 /* mask off ophdr transaction container flags */
2287 flags &= ~XLOG_END_TRANS;
2288 if (flags & XLOG_WAS_CONT_TRANS)
2289 flags &= ~XLOG_CONTINUE_TRANS;
2290
2291 /*
2292 * Callees must not free the trans structure. We'll decide if we need to
2293 * free it or not based on the operation being done and it's result.
2294 */
2295 switch (flags) {
2296 /* expected flag values */
2297 case 0:
2298 case XLOG_CONTINUE_TRANS:
2299 error = xlog_recover_add_to_trans(log, trans, dp, len);
2300 break;
2301 case XLOG_WAS_CONT_TRANS:
2302 error = xlog_recover_add_to_cont_trans(log, trans, dp, len);
2303 break;
2304 case XLOG_COMMIT_TRANS:
2305 error = xlog_recover_commit_trans(log, trans, pass,
2306 buffer_list);
2307 /* success or fail, we are now done with this transaction. */
2308 freeit = true;
2309 break;
2310
2311 /* unexpected flag values */
2312 case XLOG_UNMOUNT_TRANS:
2313 /* just skip trans */
2314 xfs_warn(log->l_mp, "%s: Unmount LR", __func__);
2315 freeit = true;
2316 break;
2317 case XLOG_START_TRANS:
2318 default:
2319 xfs_warn(log->l_mp, "%s: bad flag 0x%x", __func__, flags);
2320 ASSERT(0);
2321 error = -EFSCORRUPTED;
2322 break;
2323 }
2324 if (error || freeit)
2325 xlog_recover_free_trans(trans);
2326 return error;
2327}
2328
2329/*
2330 * Lookup the transaction recovery structure associated with the ID in the
2331 * current ophdr. If the transaction doesn't exist and the start flag is set in
2332 * the ophdr, then allocate a new transaction for future ID matches to find.
2333 * Either way, return what we found during the lookup - an existing transaction
2334 * or nothing.
2335 */
2336STATIC struct xlog_recover *
2337xlog_recover_ophdr_to_trans(
2338 struct hlist_head rhash[],
2339 struct xlog_rec_header *rhead,
2340 struct xlog_op_header *ohead)
2341{
2342 struct xlog_recover *trans;
2343 xlog_tid_t tid;
2344 struct hlist_head *rhp;
2345
2346 tid = be32_to_cpu(ohead->oh_tid);
2347 rhp = &rhash[XLOG_RHASH(tid)];
2348 hlist_for_each_entry(trans, rhp, r_list) {
2349 if (trans->r_log_tid == tid)
2350 return trans;
2351 }
2352
2353 /*
2354 * skip over non-start transaction headers - we could be
2355 * processing slack space before the next transaction starts
2356 */
2357 if (!(ohead->oh_flags & XLOG_START_TRANS))
2358 return NULL;
2359
2360 ASSERT(be32_to_cpu(ohead->oh_len) == 0);
2361
2362 /*
2363 * This is a new transaction so allocate a new recovery container to
2364 * hold the recovery ops that will follow.
2365 */
2366 trans = kzalloc(sizeof(struct xlog_recover), GFP_KERNEL | __GFP_NOFAIL);
2367 trans->r_log_tid = tid;
2368 trans->r_lsn = be64_to_cpu(rhead->h_lsn);
2369 INIT_LIST_HEAD(&trans->r_itemq);
2370 INIT_HLIST_NODE(&trans->r_list);
2371 hlist_add_head(&trans->r_list, rhp);
2372
2373 /*
2374 * Nothing more to do for this ophdr. Items to be added to this new
2375 * transaction will be in subsequent ophdr containers.
2376 */
2377 return NULL;
2378}
2379
2380STATIC int
2381xlog_recover_process_ophdr(
2382 struct xlog *log,
2383 struct hlist_head rhash[],
2384 struct xlog_rec_header *rhead,
2385 struct xlog_op_header *ohead,
2386 char *dp,
2387 char *end,
2388 int pass,
2389 struct list_head *buffer_list)
2390{
2391 struct xlog_recover *trans;
2392 unsigned int len;
2393 int error;
2394
2395 /* Do we understand who wrote this op? */
2396 if (ohead->oh_clientid != XFS_TRANSACTION &&
2397 ohead->oh_clientid != XFS_LOG) {
2398 xfs_warn(log->l_mp, "%s: bad clientid 0x%x",
2399 __func__, ohead->oh_clientid);
2400 ASSERT(0);
2401 return -EFSCORRUPTED;
2402 }
2403
2404 /*
2405 * Check the ophdr contains all the data it is supposed to contain.
2406 */
2407 len = be32_to_cpu(ohead->oh_len);
2408 if (dp + len > end) {
2409 xfs_warn(log->l_mp, "%s: bad length 0x%x", __func__, len);
2410 WARN_ON(1);
2411 return -EFSCORRUPTED;
2412 }
2413
2414 trans = xlog_recover_ophdr_to_trans(rhash, rhead, ohead);
2415 if (!trans) {
2416 /* nothing to do, so skip over this ophdr */
2417 return 0;
2418 }
2419
2420 /*
2421 * The recovered buffer queue is drained only once we know that all
2422 * recovery items for the current LSN have been processed. This is
2423 * required because:
2424 *
2425 * - Buffer write submission updates the metadata LSN of the buffer.
2426 * - Log recovery skips items with a metadata LSN >= the current LSN of
2427 * the recovery item.
2428 * - Separate recovery items against the same metadata buffer can share
2429 * a current LSN. I.e., consider that the LSN of a recovery item is
2430 * defined as the starting LSN of the first record in which its
2431 * transaction appears, that a record can hold multiple transactions,
2432 * and/or that a transaction can span multiple records.
2433 *
2434 * In other words, we are allowed to submit a buffer from log recovery
2435 * once per current LSN. Otherwise, we may incorrectly skip recovery
2436 * items and cause corruption.
2437 *
2438 * We don't know up front whether buffers are updated multiple times per
2439 * LSN. Therefore, track the current LSN of each commit log record as it
2440 * is processed and drain the queue when it changes. Use commit records
2441 * because they are ordered correctly by the logging code.
2442 */
2443 if (log->l_recovery_lsn != trans->r_lsn &&
2444 ohead->oh_flags & XLOG_COMMIT_TRANS) {
2445 error = xfs_buf_delwri_submit(buffer_list);
2446 if (error)
2447 return error;
2448 log->l_recovery_lsn = trans->r_lsn;
2449 }
2450
2451 return xlog_recovery_process_trans(log, trans, dp, len,
2452 ohead->oh_flags, pass, buffer_list);
2453}
2454
2455/*
2456 * There are two valid states of the r_state field. 0 indicates that the
2457 * transaction structure is in a normal state. We have either seen the
2458 * start of the transaction or the last operation we added was not a partial
2459 * operation. If the last operation we added to the transaction was a
2460 * partial operation, we need to mark r_state with XLOG_WAS_CONT_TRANS.
2461 *
2462 * NOTE: skip LRs with 0 data length.
2463 */
2464STATIC int
2465xlog_recover_process_data(
2466 struct xlog *log,
2467 struct hlist_head rhash[],
2468 struct xlog_rec_header *rhead,
2469 char *dp,
2470 int pass,
2471 struct list_head *buffer_list)
2472{
2473 struct xlog_op_header *ohead;
2474 char *end;
2475 int num_logops;
2476 int error;
2477
2478 end = dp + be32_to_cpu(rhead->h_len);
2479 num_logops = be32_to_cpu(rhead->h_num_logops);
2480
2481 /* check the log format matches our own - else we can't recover */
2482 if (xlog_header_check_recover(log->l_mp, rhead))
2483 return -EIO;
2484
2485 trace_xfs_log_recover_record(log, rhead, pass);
2486 while ((dp < end) && num_logops) {
2487
2488 ohead = (struct xlog_op_header *)dp;
2489 dp += sizeof(*ohead);
2490 if (dp > end) {
2491 xfs_warn(log->l_mp, "%s: op header overrun", __func__);
2492 return -EFSCORRUPTED;
2493 }
2494
2495 /* errors will abort recovery */
2496 error = xlog_recover_process_ophdr(log, rhash, rhead, ohead,
2497 dp, end, pass, buffer_list);
2498 if (error)
2499 return error;
2500
2501 dp += be32_to_cpu(ohead->oh_len);
2502 num_logops--;
2503 }
2504 return 0;
2505}
2506
2507/* Take all the collected deferred ops and finish them in order. */
2508static int
2509xlog_finish_defer_ops(
2510 struct xfs_mount *mp,
2511 struct list_head *capture_list)
2512{
2513 struct xfs_defer_capture *dfc, *next;
2514 struct xfs_trans *tp;
2515 int error = 0;
2516
2517 list_for_each_entry_safe(dfc, next, capture_list, dfc_list) {
2518 struct xfs_trans_res resv;
2519 struct xfs_defer_resources dres;
2520
2521 /*
2522 * Create a new transaction reservation from the captured
2523 * information. Set logcount to 1 to force the new transaction
2524 * to regrant every roll so that we can make forward progress
2525 * in recovery no matter how full the log might be.
2526 */
2527 resv.tr_logres = dfc->dfc_logres;
2528 resv.tr_logcount = 1;
2529 resv.tr_logflags = XFS_TRANS_PERM_LOG_RES;
2530
2531 error = xfs_trans_alloc(mp, &resv, dfc->dfc_blkres,
2532 dfc->dfc_rtxres, XFS_TRANS_RESERVE, &tp);
2533 if (error) {
2534 xlog_force_shutdown(mp->m_log, SHUTDOWN_LOG_IO_ERROR);
2535 return error;
2536 }
2537
2538 /*
2539 * Transfer to this new transaction all the dfops we captured
2540 * from recovering a single intent item.
2541 */
2542 list_del_init(&dfc->dfc_list);
2543 xfs_defer_ops_continue(dfc, tp, &dres);
2544 error = xfs_trans_commit(tp);
2545 xfs_defer_resources_rele(&dres);
2546 if (error)
2547 return error;
2548 }
2549
2550 ASSERT(list_empty(capture_list));
2551 return 0;
2552}
2553
2554/* Release all the captured defer ops and capture structures in this list. */
2555static void
2556xlog_abort_defer_ops(
2557 struct xfs_mount *mp,
2558 struct list_head *capture_list)
2559{
2560 struct xfs_defer_capture *dfc;
2561 struct xfs_defer_capture *next;
2562
2563 list_for_each_entry_safe(dfc, next, capture_list, dfc_list) {
2564 list_del_init(&dfc->dfc_list);
2565 xfs_defer_ops_capture_abort(mp, dfc);
2566 }
2567}
2568
2569/*
2570 * When this is called, all of the log intent items which did not have
2571 * corresponding log done items should be in the AIL. What we do now is update
2572 * the data structures associated with each one.
2573 *
2574 * Since we process the log intent items in normal transactions, they will be
2575 * removed at some point after the commit. This prevents us from just walking
2576 * down the list processing each one. We'll use a flag in the intent item to
2577 * skip those that we've already processed and use the AIL iteration mechanism's
2578 * generation count to try to speed this up at least a bit.
2579 *
2580 * When we start, we know that the intents are the only things in the AIL. As we
2581 * process them, however, other items are added to the AIL. Hence we know we
2582 * have started recovery on all the pending intents when we find an non-intent
2583 * item in the AIL.
2584 */
2585STATIC int
2586xlog_recover_process_intents(
2587 struct xlog *log)
2588{
2589 LIST_HEAD(capture_list);
2590 struct xfs_defer_pending *dfp, *n;
2591 int error = 0;
2592#if defined(DEBUG) || defined(XFS_WARN)
2593 xfs_lsn_t last_lsn;
2594
2595 last_lsn = xlog_assign_lsn(log->l_curr_cycle, log->l_curr_block);
2596#endif
2597
2598 list_for_each_entry_safe(dfp, n, &log->r_dfops, dfp_list) {
2599 ASSERT(xlog_item_is_intent(dfp->dfp_intent));
2600
2601 /*
2602 * We should never see a redo item with a LSN higher than
2603 * the last transaction we found in the log at the start
2604 * of recovery.
2605 */
2606 ASSERT(XFS_LSN_CMP(last_lsn, dfp->dfp_intent->li_lsn) >= 0);
2607
2608 /*
2609 * NOTE: If your intent processing routine can create more
2610 * deferred ops, you /must/ attach them to the capture list in
2611 * the recover routine or else those subsequent intents will be
2612 * replayed in the wrong order!
2613 *
2614 * The recovery function can free the log item, so we must not
2615 * access dfp->dfp_intent after it returns. It must dispose of
2616 * @dfp if it returns 0.
2617 */
2618 error = xfs_defer_finish_recovery(log->l_mp, dfp,
2619 &capture_list);
2620 if (error)
2621 break;
2622 }
2623 if (error)
2624 goto err;
2625
2626 error = xlog_finish_defer_ops(log->l_mp, &capture_list);
2627 if (error)
2628 goto err;
2629
2630 return 0;
2631err:
2632 xlog_abort_defer_ops(log->l_mp, &capture_list);
2633 return error;
2634}
2635
2636/*
2637 * A cancel occurs when the mount has failed and we're bailing out. Release all
2638 * pending log intent items that we haven't started recovery on so they don't
2639 * pin the AIL.
2640 */
2641STATIC void
2642xlog_recover_cancel_intents(
2643 struct xlog *log)
2644{
2645 struct xfs_defer_pending *dfp, *n;
2646
2647 list_for_each_entry_safe(dfp, n, &log->r_dfops, dfp_list) {
2648 ASSERT(xlog_item_is_intent(dfp->dfp_intent));
2649
2650 xfs_defer_cancel_recovery(log->l_mp, dfp);
2651 }
2652}
2653
2654/*
2655 * Transfer ownership of the recovered pending work to the recovery transaction
2656 * and try to finish the work. If there is more work to be done, the dfp will
2657 * remain attached to the transaction. If not, the dfp is freed.
2658 */
2659int
2660xlog_recover_finish_intent(
2661 struct xfs_trans *tp,
2662 struct xfs_defer_pending *dfp)
2663{
2664 int error;
2665
2666 list_move(&dfp->dfp_list, &tp->t_dfops);
2667 error = xfs_defer_finish_one(tp, dfp);
2668 if (error == -EAGAIN)
2669 return 0;
2670 return error;
2671}
2672
2673/*
2674 * This routine performs a transaction to null out a bad inode pointer
2675 * in an agi unlinked inode hash bucket.
2676 */
2677STATIC void
2678xlog_recover_clear_agi_bucket(
2679 struct xfs_perag *pag,
2680 int bucket)
2681{
2682 struct xfs_mount *mp = pag_mount(pag);
2683 struct xfs_trans *tp;
2684 struct xfs_agi *agi;
2685 struct xfs_buf *agibp;
2686 int offset;
2687 int error;
2688
2689 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_clearagi, 0, 0, 0, &tp);
2690 if (error)
2691 goto out_error;
2692
2693 error = xfs_read_agi(pag, tp, 0, &agibp);
2694 if (error)
2695 goto out_abort;
2696
2697 agi = agibp->b_addr;
2698 agi->agi_unlinked[bucket] = cpu_to_be32(NULLAGINO);
2699 offset = offsetof(xfs_agi_t, agi_unlinked) +
2700 (sizeof(xfs_agino_t) * bucket);
2701 xfs_trans_log_buf(tp, agibp, offset,
2702 (offset + sizeof(xfs_agino_t) - 1));
2703
2704 error = xfs_trans_commit(tp);
2705 if (error)
2706 goto out_error;
2707 return;
2708
2709out_abort:
2710 xfs_trans_cancel(tp);
2711out_error:
2712 xfs_warn(mp, "%s: failed to clear agi %d. Continuing.", __func__,
2713 pag_agno(pag));
2714 return;
2715}
2716
2717static int
2718xlog_recover_iunlink_bucket(
2719 struct xfs_perag *pag,
2720 struct xfs_agi *agi,
2721 int bucket)
2722{
2723 struct xfs_mount *mp = pag_mount(pag);
2724 struct xfs_inode *prev_ip = NULL;
2725 struct xfs_inode *ip;
2726 xfs_agino_t prev_agino, agino;
2727 int error = 0;
2728
2729 agino = be32_to_cpu(agi->agi_unlinked[bucket]);
2730 while (agino != NULLAGINO) {
2731 error = xfs_iget(mp, NULL, xfs_agino_to_ino(pag, agino), 0, 0,
2732 &ip);
2733 if (error)
2734 break;
2735
2736 ASSERT(VFS_I(ip)->i_nlink == 0);
2737 ASSERT(VFS_I(ip)->i_mode != 0);
2738 xfs_iflags_clear(ip, XFS_IRECOVERY);
2739 agino = ip->i_next_unlinked;
2740
2741 if (prev_ip) {
2742 ip->i_prev_unlinked = prev_agino;
2743 xfs_irele(prev_ip);
2744
2745 /*
2746 * Ensure the inode is removed from the unlinked list
2747 * before we continue so that it won't race with
2748 * building the in-memory list here. This could be
2749 * serialised with the agibp lock, but that just
2750 * serialises via lockstepping and it's much simpler
2751 * just to flush the inodegc queue and wait for it to
2752 * complete.
2753 */
2754 error = xfs_inodegc_flush(mp);
2755 if (error)
2756 break;
2757 }
2758
2759 prev_agino = agino;
2760 prev_ip = ip;
2761 }
2762
2763 if (prev_ip) {
2764 int error2;
2765
2766 ip->i_prev_unlinked = prev_agino;
2767 xfs_irele(prev_ip);
2768
2769 error2 = xfs_inodegc_flush(mp);
2770 if (error2 && !error)
2771 return error2;
2772 }
2773 return error;
2774}
2775
2776/*
2777 * Recover AGI unlinked lists
2778 *
2779 * This is called during recovery to process any inodes which we unlinked but
2780 * not freed when the system crashed. These inodes will be on the lists in the
2781 * AGI blocks. What we do here is scan all the AGIs and fully truncate and free
2782 * any inodes found on the lists. Each inode is removed from the lists when it
2783 * has been fully truncated and is freed. The freeing of the inode and its
2784 * removal from the list must be atomic.
2785 *
2786 * If everything we touch in the agi processing loop is already in memory, this
2787 * loop can hold the cpu for a long time. It runs without lock contention,
2788 * memory allocation contention, the need wait for IO, etc, and so will run
2789 * until we either run out of inodes to process, run low on memory or we run out
2790 * of log space.
2791 *
2792 * This behaviour is bad for latency on single CPU and non-preemptible kernels,
2793 * and can prevent other filesystem work (such as CIL pushes) from running. This
2794 * can lead to deadlocks if the recovery process runs out of log reservation
2795 * space. Hence we need to yield the CPU when there is other kernel work
2796 * scheduled on this CPU to ensure other scheduled work can run without undue
2797 * latency.
2798 */
2799static void
2800xlog_recover_iunlink_ag(
2801 struct xfs_perag *pag)
2802{
2803 struct xfs_agi *agi;
2804 struct xfs_buf *agibp;
2805 int bucket;
2806 int error;
2807
2808 error = xfs_read_agi(pag, NULL, 0, &agibp);
2809 if (error) {
2810 /*
2811 * AGI is b0rked. Don't process it.
2812 *
2813 * We should probably mark the filesystem as corrupt after we've
2814 * recovered all the ag's we can....
2815 */
2816 return;
2817 }
2818
2819 /*
2820 * Unlock the buffer so that it can be acquired in the normal course of
2821 * the transaction to truncate and free each inode. Because we are not
2822 * racing with anyone else here for the AGI buffer, we don't even need
2823 * to hold it locked to read the initial unlinked bucket entries out of
2824 * the buffer. We keep buffer reference though, so that it stays pinned
2825 * in memory while we need the buffer.
2826 */
2827 agi = agibp->b_addr;
2828 xfs_buf_unlock(agibp);
2829
2830 for (bucket = 0; bucket < XFS_AGI_UNLINKED_BUCKETS; bucket++) {
2831 error = xlog_recover_iunlink_bucket(pag, agi, bucket);
2832 if (error) {
2833 /*
2834 * Bucket is unrecoverable, so only a repair scan can
2835 * free the remaining unlinked inodes. Just empty the
2836 * bucket and remaining inodes on it unreferenced and
2837 * unfreeable.
2838 */
2839 xlog_recover_clear_agi_bucket(pag, bucket);
2840 }
2841 }
2842
2843 xfs_buf_rele(agibp);
2844}
2845
2846static void
2847xlog_recover_process_iunlinks(
2848 struct xlog *log)
2849{
2850 struct xfs_perag *pag = NULL;
2851
2852 while ((pag = xfs_perag_next(log->l_mp, pag)))
2853 xlog_recover_iunlink_ag(pag);
2854}
2855
2856STATIC void
2857xlog_unpack_data(
2858 struct xlog_rec_header *rhead,
2859 char *dp,
2860 struct xlog *log)
2861{
2862 int i, j, k;
2863
2864 for (i = 0; i < BTOBB(be32_to_cpu(rhead->h_len)) &&
2865 i < (XLOG_HEADER_CYCLE_SIZE / BBSIZE); i++) {
2866 *(__be32 *)dp = *(__be32 *)&rhead->h_cycle_data[i];
2867 dp += BBSIZE;
2868 }
2869
2870 if (xfs_has_logv2(log->l_mp)) {
2871 xlog_in_core_2_t *xhdr = (xlog_in_core_2_t *)rhead;
2872 for ( ; i < BTOBB(be32_to_cpu(rhead->h_len)); i++) {
2873 j = i / (XLOG_HEADER_CYCLE_SIZE / BBSIZE);
2874 k = i % (XLOG_HEADER_CYCLE_SIZE / BBSIZE);
2875 *(__be32 *)dp = xhdr[j].hic_xheader.xh_cycle_data[k];
2876 dp += BBSIZE;
2877 }
2878 }
2879}
2880
2881/*
2882 * CRC check, unpack and process a log record.
2883 */
2884STATIC int
2885xlog_recover_process(
2886 struct xlog *log,
2887 struct hlist_head rhash[],
2888 struct xlog_rec_header *rhead,
2889 char *dp,
2890 int pass,
2891 struct list_head *buffer_list)
2892{
2893 __le32 old_crc = rhead->h_crc;
2894 __le32 crc;
2895
2896 crc = xlog_cksum(log, rhead, dp, be32_to_cpu(rhead->h_len));
2897
2898 /*
2899 * Nothing else to do if this is a CRC verification pass. Just return
2900 * if this a record with a non-zero crc. Unfortunately, mkfs always
2901 * sets old_crc to 0 so we must consider this valid even on v5 supers.
2902 * Otherwise, return EFSBADCRC on failure so the callers up the stack
2903 * know precisely what failed.
2904 */
2905 if (pass == XLOG_RECOVER_CRCPASS) {
2906 if (old_crc && crc != old_crc)
2907 return -EFSBADCRC;
2908 return 0;
2909 }
2910
2911 /*
2912 * We're in the normal recovery path. Issue a warning if and only if the
2913 * CRC in the header is non-zero. This is an advisory warning and the
2914 * zero CRC check prevents warnings from being emitted when upgrading
2915 * the kernel from one that does not add CRCs by default.
2916 */
2917 if (crc != old_crc) {
2918 if (old_crc || xfs_has_crc(log->l_mp)) {
2919 xfs_alert(log->l_mp,
2920 "log record CRC mismatch: found 0x%x, expected 0x%x.",
2921 le32_to_cpu(old_crc),
2922 le32_to_cpu(crc));
2923 xfs_hex_dump(dp, 32);
2924 }
2925
2926 /*
2927 * If the filesystem is CRC enabled, this mismatch becomes a
2928 * fatal log corruption failure.
2929 */
2930 if (xfs_has_crc(log->l_mp)) {
2931 XFS_ERROR_REPORT(__func__, XFS_ERRLEVEL_LOW, log->l_mp);
2932 return -EFSCORRUPTED;
2933 }
2934 }
2935
2936 xlog_unpack_data(rhead, dp, log);
2937
2938 return xlog_recover_process_data(log, rhash, rhead, dp, pass,
2939 buffer_list);
2940}
2941
2942STATIC int
2943xlog_valid_rec_header(
2944 struct xlog *log,
2945 struct xlog_rec_header *rhead,
2946 xfs_daddr_t blkno,
2947 int bufsize)
2948{
2949 int hlen;
2950
2951 if (XFS_IS_CORRUPT(log->l_mp,
2952 rhead->h_magicno != cpu_to_be32(XLOG_HEADER_MAGIC_NUM)))
2953 return -EFSCORRUPTED;
2954 if (XFS_IS_CORRUPT(log->l_mp,
2955 (!rhead->h_version ||
2956 (be32_to_cpu(rhead->h_version) &
2957 (~XLOG_VERSION_OKBITS))))) {
2958 xfs_warn(log->l_mp, "%s: unrecognised log version (%d).",
2959 __func__, be32_to_cpu(rhead->h_version));
2960 return -EFSCORRUPTED;
2961 }
2962
2963 /*
2964 * LR body must have data (or it wouldn't have been written)
2965 * and h_len must not be greater than LR buffer size.
2966 */
2967 hlen = be32_to_cpu(rhead->h_len);
2968 if (XFS_IS_CORRUPT(log->l_mp, hlen <= 0 || hlen > bufsize))
2969 return -EFSCORRUPTED;
2970
2971 if (XFS_IS_CORRUPT(log->l_mp,
2972 blkno > log->l_logBBsize || blkno > INT_MAX))
2973 return -EFSCORRUPTED;
2974 return 0;
2975}
2976
2977/*
2978 * Read the log from tail to head and process the log records found.
2979 * Handle the two cases where the tail and head are in the same cycle
2980 * and where the active portion of the log wraps around the end of
2981 * the physical log separately. The pass parameter is passed through
2982 * to the routines called to process the data and is not looked at
2983 * here.
2984 */
2985STATIC int
2986xlog_do_recovery_pass(
2987 struct xlog *log,
2988 xfs_daddr_t head_blk,
2989 xfs_daddr_t tail_blk,
2990 int pass,
2991 xfs_daddr_t *first_bad) /* out: first bad log rec */
2992{
2993 xlog_rec_header_t *rhead;
2994 xfs_daddr_t blk_no, rblk_no;
2995 xfs_daddr_t rhead_blk;
2996 char *offset;
2997 char *hbp, *dbp;
2998 int error = 0, h_size, h_len;
2999 int error2 = 0;
3000 int bblks, split_bblks;
3001 int hblks = 1, split_hblks, wrapped_hblks;
3002 int i;
3003 struct hlist_head rhash[XLOG_RHASH_SIZE];
3004 LIST_HEAD (buffer_list);
3005
3006 ASSERT(head_blk != tail_blk);
3007 blk_no = rhead_blk = tail_blk;
3008
3009 for (i = 0; i < XLOG_RHASH_SIZE; i++)
3010 INIT_HLIST_HEAD(&rhash[i]);
3011
3012 hbp = xlog_alloc_buffer(log, hblks);
3013 if (!hbp)
3014 return -ENOMEM;
3015
3016 /*
3017 * Read the header of the tail block and get the iclog buffer size from
3018 * h_size. Use this to tell how many sectors make up the log header.
3019 */
3020 if (xfs_has_logv2(log->l_mp)) {
3021 /*
3022 * When using variable length iclogs, read first sector of
3023 * iclog header and extract the header size from it. Get a
3024 * new hbp that is the correct size.
3025 */
3026 error = xlog_bread(log, tail_blk, 1, hbp, &offset);
3027 if (error)
3028 goto bread_err1;
3029
3030 rhead = (xlog_rec_header_t *)offset;
3031
3032 /*
3033 * xfsprogs has a bug where record length is based on lsunit but
3034 * h_size (iclog size) is hardcoded to 32k. Now that we
3035 * unconditionally CRC verify the unmount record, this means the
3036 * log buffer can be too small for the record and cause an
3037 * overrun.
3038 *
3039 * Detect this condition here. Use lsunit for the buffer size as
3040 * long as this looks like the mkfs case. Otherwise, return an
3041 * error to avoid a buffer overrun.
3042 */
3043 h_size = be32_to_cpu(rhead->h_size);
3044 h_len = be32_to_cpu(rhead->h_len);
3045 if (h_len > h_size && h_len <= log->l_mp->m_logbsize &&
3046 rhead->h_num_logops == cpu_to_be32(1)) {
3047 xfs_warn(log->l_mp,
3048 "invalid iclog size (%d bytes), using lsunit (%d bytes)",
3049 h_size, log->l_mp->m_logbsize);
3050 h_size = log->l_mp->m_logbsize;
3051 }
3052
3053 error = xlog_valid_rec_header(log, rhead, tail_blk, h_size);
3054 if (error)
3055 goto bread_err1;
3056
3057 /*
3058 * This open codes xlog_logrec_hblks so that we can reuse the
3059 * fixed up h_size value calculated above. Without that we'd
3060 * still allocate the buffer based on the incorrect on-disk
3061 * size.
3062 */
3063 if (h_size > XLOG_HEADER_CYCLE_SIZE &&
3064 (rhead->h_version & cpu_to_be32(XLOG_VERSION_2))) {
3065 hblks = DIV_ROUND_UP(h_size, XLOG_HEADER_CYCLE_SIZE);
3066 if (hblks > 1) {
3067 kvfree(hbp);
3068 hbp = xlog_alloc_buffer(log, hblks);
3069 if (!hbp)
3070 return -ENOMEM;
3071 }
3072 }
3073 } else {
3074 ASSERT(log->l_sectBBsize == 1);
3075 h_size = XLOG_BIG_RECORD_BSIZE;
3076 }
3077
3078 dbp = xlog_alloc_buffer(log, BTOBB(h_size));
3079 if (!dbp) {
3080 kvfree(hbp);
3081 return -ENOMEM;
3082 }
3083
3084 memset(rhash, 0, sizeof(rhash));
3085 if (tail_blk > head_blk) {
3086 /*
3087 * Perform recovery around the end of the physical log.
3088 * When the head is not on the same cycle number as the tail,
3089 * we can't do a sequential recovery.
3090 */
3091 while (blk_no < log->l_logBBsize) {
3092 /*
3093 * Check for header wrapping around physical end-of-log
3094 */
3095 offset = hbp;
3096 split_hblks = 0;
3097 wrapped_hblks = 0;
3098 if (blk_no + hblks <= log->l_logBBsize) {
3099 /* Read header in one read */
3100 error = xlog_bread(log, blk_no, hblks, hbp,
3101 &offset);
3102 if (error)
3103 goto bread_err2;
3104 } else {
3105 /* This LR is split across physical log end */
3106 if (blk_no != log->l_logBBsize) {
3107 /* some data before physical log end */
3108 ASSERT(blk_no <= INT_MAX);
3109 split_hblks = log->l_logBBsize - (int)blk_no;
3110 ASSERT(split_hblks > 0);
3111 error = xlog_bread(log, blk_no,
3112 split_hblks, hbp,
3113 &offset);
3114 if (error)
3115 goto bread_err2;
3116 }
3117
3118 /*
3119 * Note: this black magic still works with
3120 * large sector sizes (non-512) only because:
3121 * - we increased the buffer size originally
3122 * by 1 sector giving us enough extra space
3123 * for the second read;
3124 * - the log start is guaranteed to be sector
3125 * aligned;
3126 * - we read the log end (LR header start)
3127 * _first_, then the log start (LR header end)
3128 * - order is important.
3129 */
3130 wrapped_hblks = hblks - split_hblks;
3131 error = xlog_bread_noalign(log, 0,
3132 wrapped_hblks,
3133 offset + BBTOB(split_hblks));
3134 if (error)
3135 goto bread_err2;
3136 }
3137 rhead = (xlog_rec_header_t *)offset;
3138 error = xlog_valid_rec_header(log, rhead,
3139 split_hblks ? blk_no : 0, h_size);
3140 if (error)
3141 goto bread_err2;
3142
3143 bblks = (int)BTOBB(be32_to_cpu(rhead->h_len));
3144 blk_no += hblks;
3145
3146 /*
3147 * Read the log record data in multiple reads if it
3148 * wraps around the end of the log. Note that if the
3149 * header already wrapped, blk_no could point past the
3150 * end of the log. The record data is contiguous in
3151 * that case.
3152 */
3153 if (blk_no + bblks <= log->l_logBBsize ||
3154 blk_no >= log->l_logBBsize) {
3155 rblk_no = xlog_wrap_logbno(log, blk_no);
3156 error = xlog_bread(log, rblk_no, bblks, dbp,
3157 &offset);
3158 if (error)
3159 goto bread_err2;
3160 } else {
3161 /* This log record is split across the
3162 * physical end of log */
3163 offset = dbp;
3164 split_bblks = 0;
3165 if (blk_no != log->l_logBBsize) {
3166 /* some data is before the physical
3167 * end of log */
3168 ASSERT(!wrapped_hblks);
3169 ASSERT(blk_no <= INT_MAX);
3170 split_bblks =
3171 log->l_logBBsize - (int)blk_no;
3172 ASSERT(split_bblks > 0);
3173 error = xlog_bread(log, blk_no,
3174 split_bblks, dbp,
3175 &offset);
3176 if (error)
3177 goto bread_err2;
3178 }
3179
3180 /*
3181 * Note: this black magic still works with
3182 * large sector sizes (non-512) only because:
3183 * - we increased the buffer size originally
3184 * by 1 sector giving us enough extra space
3185 * for the second read;
3186 * - the log start is guaranteed to be sector
3187 * aligned;
3188 * - we read the log end (LR header start)
3189 * _first_, then the log start (LR header end)
3190 * - order is important.
3191 */
3192 error = xlog_bread_noalign(log, 0,
3193 bblks - split_bblks,
3194 offset + BBTOB(split_bblks));
3195 if (error)
3196 goto bread_err2;
3197 }
3198
3199 error = xlog_recover_process(log, rhash, rhead, offset,
3200 pass, &buffer_list);
3201 if (error)
3202 goto bread_err2;
3203
3204 blk_no += bblks;
3205 rhead_blk = blk_no;
3206 }
3207
3208 ASSERT(blk_no >= log->l_logBBsize);
3209 blk_no -= log->l_logBBsize;
3210 rhead_blk = blk_no;
3211 }
3212
3213 /* read first part of physical log */
3214 while (blk_no < head_blk) {
3215 error = xlog_bread(log, blk_no, hblks, hbp, &offset);
3216 if (error)
3217 goto bread_err2;
3218
3219 rhead = (xlog_rec_header_t *)offset;
3220 error = xlog_valid_rec_header(log, rhead, blk_no, h_size);
3221 if (error)
3222 goto bread_err2;
3223
3224 /* blocks in data section */
3225 bblks = (int)BTOBB(be32_to_cpu(rhead->h_len));
3226 error = xlog_bread(log, blk_no+hblks, bblks, dbp,
3227 &offset);
3228 if (error)
3229 goto bread_err2;
3230
3231 error = xlog_recover_process(log, rhash, rhead, offset, pass,
3232 &buffer_list);
3233 if (error)
3234 goto bread_err2;
3235
3236 blk_no += bblks + hblks;
3237 rhead_blk = blk_no;
3238 }
3239
3240 bread_err2:
3241 kvfree(dbp);
3242 bread_err1:
3243 kvfree(hbp);
3244
3245 /*
3246 * Submit buffers that have been dirtied by the last record recovered.
3247 */
3248 if (!list_empty(&buffer_list)) {
3249 if (error) {
3250 /*
3251 * If there has been an item recovery error then we
3252 * cannot allow partial checkpoint writeback to
3253 * occur. We might have multiple checkpoints with the
3254 * same start LSN in this buffer list, and partial
3255 * writeback of a checkpoint in this situation can
3256 * prevent future recovery of all the changes in the
3257 * checkpoints at this start LSN.
3258 *
3259 * Note: Shutting down the filesystem will result in the
3260 * delwri submission marking all the buffers stale,
3261 * completing them and cleaning up _XBF_LOGRECOVERY
3262 * state without doing any IO.
3263 */
3264 xlog_force_shutdown(log, SHUTDOWN_LOG_IO_ERROR);
3265 }
3266 error2 = xfs_buf_delwri_submit(&buffer_list);
3267 }
3268
3269 if (error && first_bad)
3270 *first_bad = rhead_blk;
3271
3272 /*
3273 * Transactions are freed at commit time but transactions without commit
3274 * records on disk are never committed. Free any that may be left in the
3275 * hash table.
3276 */
3277 for (i = 0; i < XLOG_RHASH_SIZE; i++) {
3278 struct hlist_node *tmp;
3279 struct xlog_recover *trans;
3280
3281 hlist_for_each_entry_safe(trans, tmp, &rhash[i], r_list)
3282 xlog_recover_free_trans(trans);
3283 }
3284
3285 return error ? error : error2;
3286}
3287
3288/*
3289 * Do the recovery of the log. We actually do this in two phases.
3290 * The two passes are necessary in order to implement the function
3291 * of cancelling a record written into the log. The first pass
3292 * determines those things which have been cancelled, and the
3293 * second pass replays log items normally except for those which
3294 * have been cancelled. The handling of the replay and cancellations
3295 * takes place in the log item type specific routines.
3296 *
3297 * The table of items which have cancel records in the log is allocated
3298 * and freed at this level, since only here do we know when all of
3299 * the log recovery has been completed.
3300 */
3301STATIC int
3302xlog_do_log_recovery(
3303 struct xlog *log,
3304 xfs_daddr_t head_blk,
3305 xfs_daddr_t tail_blk)
3306{
3307 int error;
3308
3309 ASSERT(head_blk != tail_blk);
3310
3311 /*
3312 * First do a pass to find all of the cancelled buf log items.
3313 * Store them in the buf_cancel_table for use in the second pass.
3314 */
3315 error = xlog_alloc_buf_cancel_table(log);
3316 if (error)
3317 return error;
3318
3319 error = xlog_do_recovery_pass(log, head_blk, tail_blk,
3320 XLOG_RECOVER_PASS1, NULL);
3321 if (error != 0)
3322 goto out_cancel;
3323
3324 /*
3325 * Then do a second pass to actually recover the items in the log.
3326 * When it is complete free the table of buf cancel items.
3327 */
3328 error = xlog_do_recovery_pass(log, head_blk, tail_blk,
3329 XLOG_RECOVER_PASS2, NULL);
3330 if (!error)
3331 xlog_check_buf_cancel_table(log);
3332out_cancel:
3333 xlog_free_buf_cancel_table(log);
3334 return error;
3335}
3336
3337/*
3338 * Do the actual recovery
3339 */
3340STATIC int
3341xlog_do_recover(
3342 struct xlog *log,
3343 xfs_daddr_t head_blk,
3344 xfs_daddr_t tail_blk)
3345{
3346 struct xfs_mount *mp = log->l_mp;
3347 struct xfs_buf *bp = mp->m_sb_bp;
3348 struct xfs_sb *sbp = &mp->m_sb;
3349 int error;
3350
3351 trace_xfs_log_recover(log, head_blk, tail_blk);
3352
3353 /*
3354 * First replay the images in the log.
3355 */
3356 error = xlog_do_log_recovery(log, head_blk, tail_blk);
3357 if (error)
3358 return error;
3359
3360 if (xlog_is_shutdown(log))
3361 return -EIO;
3362
3363 /*
3364 * We now update the tail_lsn since much of the recovery has completed
3365 * and there may be space available to use. If there were no extent or
3366 * iunlinks, we can free up the entire log. This was set in
3367 * xlog_find_tail to be the lsn of the last known good LR on disk. If
3368 * there are extent frees or iunlinks they will have some entries in the
3369 * AIL; so we look at the AIL to determine how to set the tail_lsn.
3370 */
3371 xfs_ail_assign_tail_lsn(log->l_ailp);
3372
3373 /*
3374 * Now that we've finished replaying all buffer and inode updates,
3375 * re-read the superblock and reverify it.
3376 */
3377 xfs_buf_lock(bp);
3378 xfs_buf_hold(bp);
3379 error = _xfs_buf_read(bp, XBF_READ);
3380 if (error) {
3381 if (!xlog_is_shutdown(log)) {
3382 xfs_buf_ioerror_alert(bp, __this_address);
3383 ASSERT(0);
3384 }
3385 xfs_buf_relse(bp);
3386 return error;
3387 }
3388
3389 /* Convert superblock from on-disk format */
3390 xfs_sb_from_disk(sbp, bp->b_addr);
3391 xfs_buf_relse(bp);
3392
3393 /* re-initialise in-core superblock and geometry structures */
3394 mp->m_features |= xfs_sb_version_to_features(sbp);
3395 xfs_reinit_percpu_counters(mp);
3396
3397 /* Normal transactions can now occur */
3398 clear_bit(XLOG_ACTIVE_RECOVERY, &log->l_opstate);
3399 return 0;
3400}
3401
3402/*
3403 * Perform recovery and re-initialize some log variables in xlog_find_tail.
3404 *
3405 * Return error or zero.
3406 */
3407int
3408xlog_recover(
3409 struct xlog *log)
3410{
3411 xfs_daddr_t head_blk, tail_blk;
3412 int error;
3413
3414 /* find the tail of the log */
3415 error = xlog_find_tail(log, &head_blk, &tail_blk);
3416 if (error)
3417 return error;
3418
3419 /*
3420 * The superblock was read before the log was available and thus the LSN
3421 * could not be verified. Check the superblock LSN against the current
3422 * LSN now that it's known.
3423 */
3424 if (xfs_has_crc(log->l_mp) &&
3425 !xfs_log_check_lsn(log->l_mp, log->l_mp->m_sb.sb_lsn))
3426 return -EINVAL;
3427
3428 if (tail_blk != head_blk) {
3429 /* There used to be a comment here:
3430 *
3431 * disallow recovery on read-only mounts. note -- mount
3432 * checks for ENOSPC and turns it into an intelligent
3433 * error message.
3434 * ...but this is no longer true. Now, unless you specify
3435 * NORECOVERY (in which case this function would never be
3436 * called), we just go ahead and recover. We do this all
3437 * under the vfs layer, so we can get away with it unless
3438 * the device itself is read-only, in which case we fail.
3439 */
3440 if ((error = xfs_dev_is_read_only(log->l_mp, "recovery"))) {
3441 return error;
3442 }
3443
3444 /*
3445 * Version 5 superblock log feature mask validation. We know the
3446 * log is dirty so check if there are any unknown log features
3447 * in what we need to recover. If there are unknown features
3448 * (e.g. unsupported transactions, then simply reject the
3449 * attempt at recovery before touching anything.
3450 */
3451 if (xfs_sb_is_v5(&log->l_mp->m_sb) &&
3452 xfs_sb_has_incompat_log_feature(&log->l_mp->m_sb,
3453 XFS_SB_FEAT_INCOMPAT_LOG_UNKNOWN)) {
3454 xfs_warn(log->l_mp,
3455"Superblock has unknown incompatible log features (0x%x) enabled.",
3456 (log->l_mp->m_sb.sb_features_log_incompat &
3457 XFS_SB_FEAT_INCOMPAT_LOG_UNKNOWN));
3458 xfs_warn(log->l_mp,
3459"The log can not be fully and/or safely recovered by this kernel.");
3460 xfs_warn(log->l_mp,
3461"Please recover the log on a kernel that supports the unknown features.");
3462 return -EINVAL;
3463 }
3464
3465 /*
3466 * Delay log recovery if the debug hook is set. This is debug
3467 * instrumentation to coordinate simulation of I/O failures with
3468 * log recovery.
3469 */
3470 if (xfs_globals.log_recovery_delay) {
3471 xfs_notice(log->l_mp,
3472 "Delaying log recovery for %d seconds.",
3473 xfs_globals.log_recovery_delay);
3474 msleep(xfs_globals.log_recovery_delay * 1000);
3475 }
3476
3477 xfs_notice(log->l_mp, "Starting recovery (logdev: %s)",
3478 log->l_mp->m_logname ? log->l_mp->m_logname
3479 : "internal");
3480
3481 error = xlog_do_recover(log, head_blk, tail_blk);
3482 set_bit(XLOG_RECOVERY_NEEDED, &log->l_opstate);
3483 }
3484 return error;
3485}
3486
3487/*
3488 * In the first part of recovery we replay inodes and buffers and build up the
3489 * list of intents which need to be processed. Here we process the intents and
3490 * clean up the on disk unlinked inode lists. This is separated from the first
3491 * part of recovery so that the root and real-time bitmap inodes can be read in
3492 * from disk in between the two stages. This is necessary so that we can free
3493 * space in the real-time portion of the file system.
3494 *
3495 * We run this whole process under GFP_NOFS allocation context. We do a
3496 * combination of non-transactional and transactional work, yet we really don't
3497 * want to recurse into the filesystem from direct reclaim during any of this
3498 * processing. This allows all the recovery code run here not to care about the
3499 * memory allocation context it is running in.
3500 */
3501int
3502xlog_recover_finish(
3503 struct xlog *log)
3504{
3505 unsigned int nofs_flags = memalloc_nofs_save();
3506 int error;
3507
3508 error = xlog_recover_process_intents(log);
3509 if (error) {
3510 /*
3511 * Cancel all the unprocessed intent items now so that we don't
3512 * leave them pinned in the AIL. This can cause the AIL to
3513 * livelock on the pinned item if anyone tries to push the AIL
3514 * (inode reclaim does this) before we get around to
3515 * xfs_log_mount_cancel.
3516 */
3517 xlog_recover_cancel_intents(log);
3518 xfs_alert(log->l_mp, "Failed to recover intents");
3519 xlog_force_shutdown(log, SHUTDOWN_LOG_IO_ERROR);
3520 goto out_error;
3521 }
3522
3523 /*
3524 * Sync the log to get all the intents out of the AIL. This isn't
3525 * absolutely necessary, but it helps in case the unlink transactions
3526 * would have problems pushing the intents out of the way.
3527 */
3528 xfs_log_force(log->l_mp, XFS_LOG_SYNC);
3529
3530 xlog_recover_process_iunlinks(log);
3531
3532 /*
3533 * Recover any CoW staging blocks that are still referenced by the
3534 * ondisk refcount metadata. During mount there cannot be any live
3535 * staging extents as we have not permitted any user modifications.
3536 * Therefore, it is safe to free them all right now, even on a
3537 * read-only mount.
3538 */
3539 error = xfs_reflink_recover_cow(log->l_mp);
3540 if (error) {
3541 xfs_alert(log->l_mp,
3542 "Failed to recover leftover CoW staging extents, err %d.",
3543 error);
3544 /*
3545 * If we get an error here, make sure the log is shut down
3546 * but return zero so that any log items committed since the
3547 * end of intents processing can be pushed through the CIL
3548 * and AIL.
3549 */
3550 xlog_force_shutdown(log, SHUTDOWN_LOG_IO_ERROR);
3551 error = 0;
3552 goto out_error;
3553 }
3554
3555out_error:
3556 memalloc_nofs_restore(nofs_flags);
3557 return error;
3558}
3559
3560void
3561xlog_recover_cancel(
3562 struct xlog *log)
3563{
3564 if (xlog_recovery_needed(log))
3565 xlog_recover_cancel_intents(log);
3566}
3567