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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_types.h"
21#include "xfs_bit.h"
22#include "xfs_log.h"
23#include "xfs_inum.h"
24#include "xfs_trans.h"
25#include "xfs_sb.h"
26#include "xfs_ag.h"
27#include "xfs_mount.h"
28#include "xfs_error.h"
29#include "xfs_bmap_btree.h"
30#include "xfs_alloc_btree.h"
31#include "xfs_ialloc_btree.h"
32#include "xfs_dinode.h"
33#include "xfs_inode.h"
34#include "xfs_inode_item.h"
35#include "xfs_alloc.h"
36#include "xfs_ialloc.h"
37#include "xfs_log_priv.h"
38#include "xfs_buf_item.h"
39#include "xfs_log_recover.h"
40#include "xfs_extfree_item.h"
41#include "xfs_trans_priv.h"
42#include "xfs_quota.h"
43#include "xfs_rw.h"
44#include "xfs_utils.h"
45#include "xfs_trace.h"
46
47STATIC int xlog_find_zeroed(xlog_t *, xfs_daddr_t *);
48STATIC int xlog_clear_stale_blocks(xlog_t *, xfs_lsn_t);
49#if defined(DEBUG)
50STATIC void xlog_recover_check_summary(xlog_t *);
51#else
52#define xlog_recover_check_summary(log)
53#endif
54
55/*
56 * This structure is used during recovery to record the buf log items which
57 * have been canceled and should not be replayed.
58 */
59struct xfs_buf_cancel {
60 xfs_daddr_t bc_blkno;
61 uint bc_len;
62 int bc_refcount;
63 struct list_head bc_list;
64};
65
66/*
67 * Sector aligned buffer routines for buffer create/read/write/access
68 */
69
70/*
71 * Verify the given count of basic blocks is valid number of blocks
72 * to specify for an operation involving the given XFS log buffer.
73 * Returns nonzero if the count is valid, 0 otherwise.
74 */
75
76static inline int
77xlog_buf_bbcount_valid(
78 xlog_t *log,
79 int bbcount)
80{
81 return bbcount > 0 && bbcount <= log->l_logBBsize;
82}
83
84/*
85 * Allocate a buffer to hold log data. The buffer needs to be able
86 * to map to a range of nbblks basic blocks at any valid (basic
87 * block) offset within the log.
88 */
89STATIC xfs_buf_t *
90xlog_get_bp(
91 xlog_t *log,
92 int nbblks)
93{
94 struct xfs_buf *bp;
95
96 if (!xlog_buf_bbcount_valid(log, nbblks)) {
97 xfs_warn(log->l_mp, "Invalid block length (0x%x) for buffer",
98 nbblks);
99 XFS_ERROR_REPORT(__func__, XFS_ERRLEVEL_HIGH, log->l_mp);
100 return NULL;
101 }
102
103 /*
104 * We do log I/O in units of log sectors (a power-of-2
105 * multiple of the basic block size), so we round up the
106 * requested size to accommodate the basic blocks required
107 * for complete log sectors.
108 *
109 * In addition, the buffer may be used for a non-sector-
110 * aligned block offset, in which case an I/O of the
111 * requested size could extend beyond the end of the
112 * buffer. If the requested size is only 1 basic block it
113 * will never straddle a sector boundary, so this won't be
114 * an issue. Nor will this be a problem if the log I/O is
115 * done in basic blocks (sector size 1). But otherwise we
116 * extend the buffer by one extra log sector to ensure
117 * there's space to accommodate this possibility.
118 */
119 if (nbblks > 1 && log->l_sectBBsize > 1)
120 nbblks += log->l_sectBBsize;
121 nbblks = round_up(nbblks, log->l_sectBBsize);
122
123 bp = xfs_buf_get_uncached(log->l_mp->m_logdev_targp, BBTOB(nbblks), 0);
124 if (bp)
125 xfs_buf_unlock(bp);
126 return bp;
127}
128
129STATIC void
130xlog_put_bp(
131 xfs_buf_t *bp)
132{
133 xfs_buf_free(bp);
134}
135
136/*
137 * Return the address of the start of the given block number's data
138 * in a log buffer. The buffer covers a log sector-aligned region.
139 */
140STATIC xfs_caddr_t
141xlog_align(
142 xlog_t *log,
143 xfs_daddr_t blk_no,
144 int nbblks,
145 xfs_buf_t *bp)
146{
147 xfs_daddr_t offset = blk_no & ((xfs_daddr_t)log->l_sectBBsize - 1);
148
149 ASSERT(BBTOB(offset + nbblks) <= XFS_BUF_SIZE(bp));
150 return bp->b_addr + BBTOB(offset);
151}
152
153
154/*
155 * nbblks should be uint, but oh well. Just want to catch that 32-bit length.
156 */
157STATIC int
158xlog_bread_noalign(
159 xlog_t *log,
160 xfs_daddr_t blk_no,
161 int nbblks,
162 xfs_buf_t *bp)
163{
164 int error;
165
166 if (!xlog_buf_bbcount_valid(log, nbblks)) {
167 xfs_warn(log->l_mp, "Invalid block length (0x%x) for buffer",
168 nbblks);
169 XFS_ERROR_REPORT(__func__, XFS_ERRLEVEL_HIGH, log->l_mp);
170 return EFSCORRUPTED;
171 }
172
173 blk_no = round_down(blk_no, log->l_sectBBsize);
174 nbblks = round_up(nbblks, log->l_sectBBsize);
175
176 ASSERT(nbblks > 0);
177 ASSERT(BBTOB(nbblks) <= XFS_BUF_SIZE(bp));
178
179 XFS_BUF_SET_ADDR(bp, log->l_logBBstart + blk_no);
180 XFS_BUF_READ(bp);
181 XFS_BUF_SET_COUNT(bp, BBTOB(nbblks));
182
183 xfsbdstrat(log->l_mp, bp);
184 error = xfs_buf_iowait(bp);
185 if (error)
186 xfs_ioerror_alert("xlog_bread", log->l_mp,
187 bp, XFS_BUF_ADDR(bp));
188 return error;
189}
190
191STATIC int
192xlog_bread(
193 xlog_t *log,
194 xfs_daddr_t blk_no,
195 int nbblks,
196 xfs_buf_t *bp,
197 xfs_caddr_t *offset)
198{
199 int error;
200
201 error = xlog_bread_noalign(log, blk_no, nbblks, bp);
202 if (error)
203 return error;
204
205 *offset = xlog_align(log, blk_no, nbblks, bp);
206 return 0;
207}
208
209/*
210 * Read at an offset into the buffer. Returns with the buffer in it's original
211 * state regardless of the result of the read.
212 */
213STATIC int
214xlog_bread_offset(
215 xlog_t *log,
216 xfs_daddr_t blk_no, /* block to read from */
217 int nbblks, /* blocks to read */
218 xfs_buf_t *bp,
219 xfs_caddr_t offset)
220{
221 xfs_caddr_t orig_offset = bp->b_addr;
222 int orig_len = bp->b_buffer_length;
223 int error, error2;
224
225 error = xfs_buf_associate_memory(bp, offset, BBTOB(nbblks));
226 if (error)
227 return error;
228
229 error = xlog_bread_noalign(log, blk_no, nbblks, bp);
230
231 /* must reset buffer pointer even on error */
232 error2 = xfs_buf_associate_memory(bp, orig_offset, orig_len);
233 if (error)
234 return error;
235 return error2;
236}
237
238/*
239 * Write out the buffer at the given block for the given number of blocks.
240 * The buffer is kept locked across the write and is returned locked.
241 * This can only be used for synchronous log writes.
242 */
243STATIC int
244xlog_bwrite(
245 xlog_t *log,
246 xfs_daddr_t blk_no,
247 int nbblks,
248 xfs_buf_t *bp)
249{
250 int error;
251
252 if (!xlog_buf_bbcount_valid(log, nbblks)) {
253 xfs_warn(log->l_mp, "Invalid block length (0x%x) for buffer",
254 nbblks);
255 XFS_ERROR_REPORT(__func__, XFS_ERRLEVEL_HIGH, log->l_mp);
256 return EFSCORRUPTED;
257 }
258
259 blk_no = round_down(blk_no, log->l_sectBBsize);
260 nbblks = round_up(nbblks, log->l_sectBBsize);
261
262 ASSERT(nbblks > 0);
263 ASSERT(BBTOB(nbblks) <= XFS_BUF_SIZE(bp));
264
265 XFS_BUF_SET_ADDR(bp, log->l_logBBstart + blk_no);
266 XFS_BUF_ZEROFLAGS(bp);
267 xfs_buf_hold(bp);
268 xfs_buf_lock(bp);
269 XFS_BUF_SET_COUNT(bp, BBTOB(nbblks));
270
271 if ((error = xfs_bwrite(log->l_mp, bp)))
272 xfs_ioerror_alert("xlog_bwrite", log->l_mp,
273 bp, XFS_BUF_ADDR(bp));
274 return error;
275}
276
277#ifdef DEBUG
278/*
279 * dump debug superblock and log record information
280 */
281STATIC void
282xlog_header_check_dump(
283 xfs_mount_t *mp,
284 xlog_rec_header_t *head)
285{
286 xfs_debug(mp, "%s: SB : uuid = %pU, fmt = %d\n",
287 __func__, &mp->m_sb.sb_uuid, XLOG_FMT);
288 xfs_debug(mp, " log : uuid = %pU, fmt = %d\n",
289 &head->h_fs_uuid, be32_to_cpu(head->h_fmt));
290}
291#else
292#define xlog_header_check_dump(mp, head)
293#endif
294
295/*
296 * check log record header for recovery
297 */
298STATIC int
299xlog_header_check_recover(
300 xfs_mount_t *mp,
301 xlog_rec_header_t *head)
302{
303 ASSERT(head->h_magicno == cpu_to_be32(XLOG_HEADER_MAGIC_NUM));
304
305 /*
306 * IRIX doesn't write the h_fmt field and leaves it zeroed
307 * (XLOG_FMT_UNKNOWN). This stops us from trying to recover
308 * a dirty log created in IRIX.
309 */
310 if (unlikely(head->h_fmt != cpu_to_be32(XLOG_FMT))) {
311 xfs_warn(mp,
312 "dirty log written in incompatible format - can't recover");
313 xlog_header_check_dump(mp, head);
314 XFS_ERROR_REPORT("xlog_header_check_recover(1)",
315 XFS_ERRLEVEL_HIGH, mp);
316 return XFS_ERROR(EFSCORRUPTED);
317 } else if (unlikely(!uuid_equal(&mp->m_sb.sb_uuid, &head->h_fs_uuid))) {
318 xfs_warn(mp,
319 "dirty log entry has mismatched uuid - can't recover");
320 xlog_header_check_dump(mp, head);
321 XFS_ERROR_REPORT("xlog_header_check_recover(2)",
322 XFS_ERRLEVEL_HIGH, mp);
323 return XFS_ERROR(EFSCORRUPTED);
324 }
325 return 0;
326}
327
328/*
329 * read the head block of the log and check the header
330 */
331STATIC int
332xlog_header_check_mount(
333 xfs_mount_t *mp,
334 xlog_rec_header_t *head)
335{
336 ASSERT(head->h_magicno == cpu_to_be32(XLOG_HEADER_MAGIC_NUM));
337
338 if (uuid_is_nil(&head->h_fs_uuid)) {
339 /*
340 * IRIX doesn't write the h_fs_uuid or h_fmt fields. If
341 * h_fs_uuid is nil, we assume this log was last mounted
342 * by IRIX and continue.
343 */
344 xfs_warn(mp, "nil uuid in log - IRIX style log");
345 } else if (unlikely(!uuid_equal(&mp->m_sb.sb_uuid, &head->h_fs_uuid))) {
346 xfs_warn(mp, "log has mismatched uuid - can't recover");
347 xlog_header_check_dump(mp, head);
348 XFS_ERROR_REPORT("xlog_header_check_mount",
349 XFS_ERRLEVEL_HIGH, mp);
350 return XFS_ERROR(EFSCORRUPTED);
351 }
352 return 0;
353}
354
355STATIC void
356xlog_recover_iodone(
357 struct xfs_buf *bp)
358{
359 if (bp->b_error) {
360 /*
361 * We're not going to bother about retrying
362 * this during recovery. One strike!
363 */
364 xfs_ioerror_alert("xlog_recover_iodone",
365 bp->b_target->bt_mount, bp,
366 XFS_BUF_ADDR(bp));
367 xfs_force_shutdown(bp->b_target->bt_mount,
368 SHUTDOWN_META_IO_ERROR);
369 }
370 bp->b_iodone = NULL;
371 xfs_buf_ioend(bp, 0);
372}
373
374/*
375 * This routine finds (to an approximation) the first block in the physical
376 * log which contains the given cycle. It uses a binary search algorithm.
377 * Note that the algorithm can not be perfect because the disk will not
378 * necessarily be perfect.
379 */
380STATIC int
381xlog_find_cycle_start(
382 xlog_t *log,
383 xfs_buf_t *bp,
384 xfs_daddr_t first_blk,
385 xfs_daddr_t *last_blk,
386 uint cycle)
387{
388 xfs_caddr_t offset;
389 xfs_daddr_t mid_blk;
390 xfs_daddr_t end_blk;
391 uint mid_cycle;
392 int error;
393
394 end_blk = *last_blk;
395 mid_blk = BLK_AVG(first_blk, end_blk);
396 while (mid_blk != first_blk && mid_blk != end_blk) {
397 error = xlog_bread(log, mid_blk, 1, bp, &offset);
398 if (error)
399 return error;
400 mid_cycle = xlog_get_cycle(offset);
401 if (mid_cycle == cycle)
402 end_blk = mid_blk; /* last_half_cycle == mid_cycle */
403 else
404 first_blk = mid_blk; /* first_half_cycle == mid_cycle */
405 mid_blk = BLK_AVG(first_blk, end_blk);
406 }
407 ASSERT((mid_blk == first_blk && mid_blk+1 == end_blk) ||
408 (mid_blk == end_blk && mid_blk-1 == first_blk));
409
410 *last_blk = end_blk;
411
412 return 0;
413}
414
415/*
416 * Check that a range of blocks does not contain stop_on_cycle_no.
417 * Fill in *new_blk with the block offset where such a block is
418 * found, or with -1 (an invalid block number) if there is no such
419 * block in the range. The scan needs to occur from front to back
420 * and the pointer into the region must be updated since a later
421 * routine will need to perform another test.
422 */
423STATIC int
424xlog_find_verify_cycle(
425 xlog_t *log,
426 xfs_daddr_t start_blk,
427 int nbblks,
428 uint stop_on_cycle_no,
429 xfs_daddr_t *new_blk)
430{
431 xfs_daddr_t i, j;
432 uint cycle;
433 xfs_buf_t *bp;
434 xfs_daddr_t bufblks;
435 xfs_caddr_t buf = NULL;
436 int error = 0;
437
438 /*
439 * Greedily allocate a buffer big enough to handle the full
440 * range of basic blocks we'll be examining. If that fails,
441 * try a smaller size. We need to be able to read at least
442 * a log sector, or we're out of luck.
443 */
444 bufblks = 1 << ffs(nbblks);
445 while (!(bp = xlog_get_bp(log, bufblks))) {
446 bufblks >>= 1;
447 if (bufblks < log->l_sectBBsize)
448 return ENOMEM;
449 }
450
451 for (i = start_blk; i < start_blk + nbblks; i += bufblks) {
452 int bcount;
453
454 bcount = min(bufblks, (start_blk + nbblks - i));
455
456 error = xlog_bread(log, i, bcount, bp, &buf);
457 if (error)
458 goto out;
459
460 for (j = 0; j < bcount; j++) {
461 cycle = xlog_get_cycle(buf);
462 if (cycle == stop_on_cycle_no) {
463 *new_blk = i+j;
464 goto out;
465 }
466
467 buf += BBSIZE;
468 }
469 }
470
471 *new_blk = -1;
472
473out:
474 xlog_put_bp(bp);
475 return error;
476}
477
478/*
479 * Potentially backup over partial log record write.
480 *
481 * In the typical case, last_blk is the number of the block directly after
482 * a good log record. Therefore, we subtract one to get the block number
483 * of the last block in the given buffer. extra_bblks contains the number
484 * of blocks we would have read on a previous read. This happens when the
485 * last log record is split over the end of the physical log.
486 *
487 * extra_bblks is the number of blocks potentially verified on a previous
488 * call to this routine.
489 */
490STATIC int
491xlog_find_verify_log_record(
492 xlog_t *log,
493 xfs_daddr_t start_blk,
494 xfs_daddr_t *last_blk,
495 int extra_bblks)
496{
497 xfs_daddr_t i;
498 xfs_buf_t *bp;
499 xfs_caddr_t offset = NULL;
500 xlog_rec_header_t *head = NULL;
501 int error = 0;
502 int smallmem = 0;
503 int num_blks = *last_blk - start_blk;
504 int xhdrs;
505
506 ASSERT(start_blk != 0 || *last_blk != start_blk);
507
508 if (!(bp = xlog_get_bp(log, num_blks))) {
509 if (!(bp = xlog_get_bp(log, 1)))
510 return ENOMEM;
511 smallmem = 1;
512 } else {
513 error = xlog_bread(log, start_blk, num_blks, bp, &offset);
514 if (error)
515 goto out;
516 offset += ((num_blks - 1) << BBSHIFT);
517 }
518
519 for (i = (*last_blk) - 1; i >= 0; i--) {
520 if (i < start_blk) {
521 /* valid log record not found */
522 xfs_warn(log->l_mp,
523 "Log inconsistent (didn't find previous header)");
524 ASSERT(0);
525 error = XFS_ERROR(EIO);
526 goto out;
527 }
528
529 if (smallmem) {
530 error = xlog_bread(log, i, 1, bp, &offset);
531 if (error)
532 goto out;
533 }
534
535 head = (xlog_rec_header_t *)offset;
536
537 if (head->h_magicno == cpu_to_be32(XLOG_HEADER_MAGIC_NUM))
538 break;
539
540 if (!smallmem)
541 offset -= BBSIZE;
542 }
543
544 /*
545 * We hit the beginning of the physical log & still no header. Return
546 * to caller. If caller can handle a return of -1, then this routine
547 * will be called again for the end of the physical log.
548 */
549 if (i == -1) {
550 error = -1;
551 goto out;
552 }
553
554 /*
555 * We have the final block of the good log (the first block
556 * of the log record _before_ the head. So we check the uuid.
557 */
558 if ((error = xlog_header_check_mount(log->l_mp, head)))
559 goto out;
560
561 /*
562 * We may have found a log record header before we expected one.
563 * last_blk will be the 1st block # with a given cycle #. We may end
564 * up reading an entire log record. In this case, we don't want to
565 * reset last_blk. Only when last_blk points in the middle of a log
566 * record do we update last_blk.
567 */
568 if (xfs_sb_version_haslogv2(&log->l_mp->m_sb)) {
569 uint h_size = be32_to_cpu(head->h_size);
570
571 xhdrs = h_size / XLOG_HEADER_CYCLE_SIZE;
572 if (h_size % XLOG_HEADER_CYCLE_SIZE)
573 xhdrs++;
574 } else {
575 xhdrs = 1;
576 }
577
578 if (*last_blk - i + extra_bblks !=
579 BTOBB(be32_to_cpu(head->h_len)) + xhdrs)
580 *last_blk = i;
581
582out:
583 xlog_put_bp(bp);
584 return error;
585}
586
587/*
588 * Head is defined to be the point of the log where the next log write
589 * write could go. This means that incomplete LR writes at the end are
590 * eliminated when calculating the head. We aren't guaranteed that previous
591 * LR have complete transactions. We only know that a cycle number of
592 * current cycle number -1 won't be present in the log if we start writing
593 * from our current block number.
594 *
595 * last_blk contains the block number of the first block with a given
596 * cycle number.
597 *
598 * Return: zero if normal, non-zero if error.
599 */
600STATIC int
601xlog_find_head(
602 xlog_t *log,
603 xfs_daddr_t *return_head_blk)
604{
605 xfs_buf_t *bp;
606 xfs_caddr_t offset;
607 xfs_daddr_t new_blk, first_blk, start_blk, last_blk, head_blk;
608 int num_scan_bblks;
609 uint first_half_cycle, last_half_cycle;
610 uint stop_on_cycle;
611 int error, log_bbnum = log->l_logBBsize;
612
613 /* Is the end of the log device zeroed? */
614 if ((error = xlog_find_zeroed(log, &first_blk)) == -1) {
615 *return_head_blk = first_blk;
616
617 /* Is the whole lot zeroed? */
618 if (!first_blk) {
619 /* Linux XFS shouldn't generate totally zeroed logs -
620 * mkfs etc write a dummy unmount record to a fresh
621 * log so we can store the uuid in there
622 */
623 xfs_warn(log->l_mp, "totally zeroed log");
624 }
625
626 return 0;
627 } else if (error) {
628 xfs_warn(log->l_mp, "empty log check failed");
629 return error;
630 }
631
632 first_blk = 0; /* get cycle # of 1st block */
633 bp = xlog_get_bp(log, 1);
634 if (!bp)
635 return ENOMEM;
636
637 error = xlog_bread(log, 0, 1, bp, &offset);
638 if (error)
639 goto bp_err;
640
641 first_half_cycle = xlog_get_cycle(offset);
642
643 last_blk = head_blk = log_bbnum - 1; /* get cycle # of last block */
644 error = xlog_bread(log, last_blk, 1, bp, &offset);
645 if (error)
646 goto bp_err;
647
648 last_half_cycle = xlog_get_cycle(offset);
649 ASSERT(last_half_cycle != 0);
650
651 /*
652 * If the 1st half cycle number is equal to the last half cycle number,
653 * then the entire log is stamped with the same cycle number. In this
654 * case, head_blk can't be set to zero (which makes sense). The below
655 * math doesn't work out properly with head_blk equal to zero. Instead,
656 * we set it to log_bbnum which is an invalid block number, but this
657 * value makes the math correct. If head_blk doesn't changed through
658 * all the tests below, *head_blk is set to zero at the very end rather
659 * than log_bbnum. In a sense, log_bbnum and zero are the same block
660 * in a circular file.
661 */
662 if (first_half_cycle == last_half_cycle) {
663 /*
664 * In this case we believe that the entire log should have
665 * cycle number last_half_cycle. We need to scan backwards
666 * from the end verifying that there are no holes still
667 * containing last_half_cycle - 1. If we find such a hole,
668 * then the start of that hole will be the new head. The
669 * simple case looks like
670 * x | x ... | x - 1 | x
671 * Another case that fits this picture would be
672 * x | x + 1 | x ... | x
673 * In this case the head really is somewhere at the end of the
674 * log, as one of the latest writes at the beginning was
675 * incomplete.
676 * One more case is
677 * x | x + 1 | x ... | x - 1 | x
678 * This is really the combination of the above two cases, and
679 * the head has to end up at the start of the x-1 hole at the
680 * end of the log.
681 *
682 * In the 256k log case, we will read from the beginning to the
683 * end of the log and search for cycle numbers equal to x-1.
684 * We don't worry about the x+1 blocks that we encounter,
685 * because we know that they cannot be the head since the log
686 * started with x.
687 */
688 head_blk = log_bbnum;
689 stop_on_cycle = last_half_cycle - 1;
690 } else {
691 /*
692 * In this case we want to find the first block with cycle
693 * number matching last_half_cycle. We expect the log to be
694 * some variation on
695 * x + 1 ... | x ... | x
696 * The first block with cycle number x (last_half_cycle) will
697 * be where the new head belongs. First we do a binary search
698 * for the first occurrence of last_half_cycle. The binary
699 * search may not be totally accurate, so then we scan back
700 * from there looking for occurrences of last_half_cycle before
701 * us. If that backwards scan wraps around the beginning of
702 * the log, then we look for occurrences of last_half_cycle - 1
703 * at the end of the log. The cases we're looking for look
704 * like
705 * v binary search stopped here
706 * x + 1 ... | x | x + 1 | x ... | x
707 * ^ but we want to locate this spot
708 * or
709 * <---------> less than scan distance
710 * x + 1 ... | x ... | x - 1 | x
711 * ^ we want to locate this spot
712 */
713 stop_on_cycle = last_half_cycle;
714 if ((error = xlog_find_cycle_start(log, bp, first_blk,
715 &head_blk, last_half_cycle)))
716 goto bp_err;
717 }
718
719 /*
720 * Now validate the answer. Scan back some number of maximum possible
721 * blocks and make sure each one has the expected cycle number. The
722 * maximum is determined by the total possible amount of buffering
723 * in the in-core log. The following number can be made tighter if
724 * we actually look at the block size of the filesystem.
725 */
726 num_scan_bblks = XLOG_TOTAL_REC_SHIFT(log);
727 if (head_blk >= num_scan_bblks) {
728 /*
729 * We are guaranteed that the entire check can be performed
730 * in one buffer.
731 */
732 start_blk = head_blk - num_scan_bblks;
733 if ((error = xlog_find_verify_cycle(log,
734 start_blk, num_scan_bblks,
735 stop_on_cycle, &new_blk)))
736 goto bp_err;
737 if (new_blk != -1)
738 head_blk = new_blk;
739 } else { /* need to read 2 parts of log */
740 /*
741 * We are going to scan backwards in the log in two parts.
742 * First we scan the physical end of the log. In this part
743 * of the log, we are looking for blocks with cycle number
744 * last_half_cycle - 1.
745 * If we find one, then we know that the log starts there, as
746 * we've found a hole that didn't get written in going around
747 * the end of the physical log. The simple case for this is
748 * x + 1 ... | x ... | x - 1 | x
749 * <---------> less than scan distance
750 * If all of the blocks at the end of the log have cycle number
751 * last_half_cycle, then we check the blocks at the start of
752 * the log looking for occurrences of last_half_cycle. If we
753 * find one, then our current estimate for the location of the
754 * first occurrence of last_half_cycle is wrong and we move
755 * back to the hole we've found. This case looks like
756 * x + 1 ... | x | x + 1 | x ...
757 * ^ binary search stopped here
758 * Another case we need to handle that only occurs in 256k
759 * logs is
760 * x + 1 ... | x ... | x+1 | x ...
761 * ^ binary search stops here
762 * In a 256k log, the scan at the end of the log will see the
763 * x + 1 blocks. We need to skip past those since that is
764 * certainly not the head of the log. By searching for
765 * last_half_cycle-1 we accomplish that.
766 */
767 ASSERT(head_blk <= INT_MAX &&
768 (xfs_daddr_t) num_scan_bblks >= head_blk);
769 start_blk = log_bbnum - (num_scan_bblks - head_blk);
770 if ((error = xlog_find_verify_cycle(log, start_blk,
771 num_scan_bblks - (int)head_blk,
772 (stop_on_cycle - 1), &new_blk)))
773 goto bp_err;
774 if (new_blk != -1) {
775 head_blk = new_blk;
776 goto validate_head;
777 }
778
779 /*
780 * Scan beginning of log now. The last part of the physical
781 * log is good. This scan needs to verify that it doesn't find
782 * the last_half_cycle.
783 */
784 start_blk = 0;
785 ASSERT(head_blk <= INT_MAX);
786 if ((error = xlog_find_verify_cycle(log,
787 start_blk, (int)head_blk,
788 stop_on_cycle, &new_blk)))
789 goto bp_err;
790 if (new_blk != -1)
791 head_blk = new_blk;
792 }
793
794validate_head:
795 /*
796 * Now we need to make sure head_blk is not pointing to a block in
797 * the middle of a log record.
798 */
799 num_scan_bblks = XLOG_REC_SHIFT(log);
800 if (head_blk >= num_scan_bblks) {
801 start_blk = head_blk - num_scan_bblks; /* don't read head_blk */
802
803 /* start ptr at last block ptr before head_blk */
804 if ((error = xlog_find_verify_log_record(log, start_blk,
805 &head_blk, 0)) == -1) {
806 error = XFS_ERROR(EIO);
807 goto bp_err;
808 } else if (error)
809 goto bp_err;
810 } else {
811 start_blk = 0;
812 ASSERT(head_blk <= INT_MAX);
813 if ((error = xlog_find_verify_log_record(log, start_blk,
814 &head_blk, 0)) == -1) {
815 /* We hit the beginning of the log during our search */
816 start_blk = log_bbnum - (num_scan_bblks - head_blk);
817 new_blk = log_bbnum;
818 ASSERT(start_blk <= INT_MAX &&
819 (xfs_daddr_t) log_bbnum-start_blk >= 0);
820 ASSERT(head_blk <= INT_MAX);
821 if ((error = xlog_find_verify_log_record(log,
822 start_blk, &new_blk,
823 (int)head_blk)) == -1) {
824 error = XFS_ERROR(EIO);
825 goto bp_err;
826 } else if (error)
827 goto bp_err;
828 if (new_blk != log_bbnum)
829 head_blk = new_blk;
830 } else if (error)
831 goto bp_err;
832 }
833
834 xlog_put_bp(bp);
835 if (head_blk == log_bbnum)
836 *return_head_blk = 0;
837 else
838 *return_head_blk = head_blk;
839 /*
840 * When returning here, we have a good block number. Bad block
841 * means that during a previous crash, we didn't have a clean break
842 * from cycle number N to cycle number N-1. In this case, we need
843 * to find the first block with cycle number N-1.
844 */
845 return 0;
846
847 bp_err:
848 xlog_put_bp(bp);
849
850 if (error)
851 xfs_warn(log->l_mp, "failed to find log head");
852 return error;
853}
854
855/*
856 * Find the sync block number or the tail of the log.
857 *
858 * This will be the block number of the last record to have its
859 * associated buffers synced to disk. Every log record header has
860 * a sync lsn embedded in it. LSNs hold block numbers, so it is easy
861 * to get a sync block number. The only concern is to figure out which
862 * log record header to believe.
863 *
864 * The following algorithm uses the log record header with the largest
865 * lsn. The entire log record does not need to be valid. We only care
866 * that the header is valid.
867 *
868 * We could speed up search by using current head_blk buffer, but it is not
869 * available.
870 */
871STATIC int
872xlog_find_tail(
873 xlog_t *log,
874 xfs_daddr_t *head_blk,
875 xfs_daddr_t *tail_blk)
876{
877 xlog_rec_header_t *rhead;
878 xlog_op_header_t *op_head;
879 xfs_caddr_t offset = NULL;
880 xfs_buf_t *bp;
881 int error, i, found;
882 xfs_daddr_t umount_data_blk;
883 xfs_daddr_t after_umount_blk;
884 xfs_lsn_t tail_lsn;
885 int hblks;
886
887 found = 0;
888
889 /*
890 * Find previous log record
891 */
892 if ((error = xlog_find_head(log, head_blk)))
893 return error;
894
895 bp = xlog_get_bp(log, 1);
896 if (!bp)
897 return ENOMEM;
898 if (*head_blk == 0) { /* special case */
899 error = xlog_bread(log, 0, 1, bp, &offset);
900 if (error)
901 goto done;
902
903 if (xlog_get_cycle(offset) == 0) {
904 *tail_blk = 0;
905 /* leave all other log inited values alone */
906 goto done;
907 }
908 }
909
910 /*
911 * Search backwards looking for log record header block
912 */
913 ASSERT(*head_blk < INT_MAX);
914 for (i = (int)(*head_blk) - 1; i >= 0; i--) {
915 error = xlog_bread(log, i, 1, bp, &offset);
916 if (error)
917 goto done;
918
919 if (*(__be32 *)offset == cpu_to_be32(XLOG_HEADER_MAGIC_NUM)) {
920 found = 1;
921 break;
922 }
923 }
924 /*
925 * If we haven't found the log record header block, start looking
926 * again from the end of the physical log. XXXmiken: There should be
927 * a check here to make sure we didn't search more than N blocks in
928 * the previous code.
929 */
930 if (!found) {
931 for (i = log->l_logBBsize - 1; i >= (int)(*head_blk); i--) {
932 error = xlog_bread(log, i, 1, bp, &offset);
933 if (error)
934 goto done;
935
936 if (*(__be32 *)offset ==
937 cpu_to_be32(XLOG_HEADER_MAGIC_NUM)) {
938 found = 2;
939 break;
940 }
941 }
942 }
943 if (!found) {
944 xfs_warn(log->l_mp, "%s: couldn't find sync record", __func__);
945 ASSERT(0);
946 return XFS_ERROR(EIO);
947 }
948
949 /* find blk_no of tail of log */
950 rhead = (xlog_rec_header_t *)offset;
951 *tail_blk = BLOCK_LSN(be64_to_cpu(rhead->h_tail_lsn));
952
953 /*
954 * Reset log values according to the state of the log when we
955 * crashed. In the case where head_blk == 0, we bump curr_cycle
956 * one because the next write starts a new cycle rather than
957 * continuing the cycle of the last good log record. At this
958 * point we have guaranteed that all partial log records have been
959 * accounted for. Therefore, we know that the last good log record
960 * written was complete and ended exactly on the end boundary
961 * of the physical log.
962 */
963 log->l_prev_block = i;
964 log->l_curr_block = (int)*head_blk;
965 log->l_curr_cycle = be32_to_cpu(rhead->h_cycle);
966 if (found == 2)
967 log->l_curr_cycle++;
968 atomic64_set(&log->l_tail_lsn, be64_to_cpu(rhead->h_tail_lsn));
969 atomic64_set(&log->l_last_sync_lsn, be64_to_cpu(rhead->h_lsn));
970 xlog_assign_grant_head(&log->l_grant_reserve_head, log->l_curr_cycle,
971 BBTOB(log->l_curr_block));
972 xlog_assign_grant_head(&log->l_grant_write_head, log->l_curr_cycle,
973 BBTOB(log->l_curr_block));
974
975 /*
976 * Look for unmount record. If we find it, then we know there
977 * was a clean unmount. Since 'i' could be the last block in
978 * the physical log, we convert to a log block before comparing
979 * to the head_blk.
980 *
981 * Save the current tail lsn to use to pass to
982 * xlog_clear_stale_blocks() below. We won't want to clear the
983 * unmount record if there is one, so we pass the lsn of the
984 * unmount record rather than the block after it.
985 */
986 if (xfs_sb_version_haslogv2(&log->l_mp->m_sb)) {
987 int h_size = be32_to_cpu(rhead->h_size);
988 int h_version = be32_to_cpu(rhead->h_version);
989
990 if ((h_version & XLOG_VERSION_2) &&
991 (h_size > XLOG_HEADER_CYCLE_SIZE)) {
992 hblks = h_size / XLOG_HEADER_CYCLE_SIZE;
993 if (h_size % XLOG_HEADER_CYCLE_SIZE)
994 hblks++;
995 } else {
996 hblks = 1;
997 }
998 } else {
999 hblks = 1;
1000 }
1001 after_umount_blk = (i + hblks + (int)
1002 BTOBB(be32_to_cpu(rhead->h_len))) % log->l_logBBsize;
1003 tail_lsn = atomic64_read(&log->l_tail_lsn);
1004 if (*head_blk == after_umount_blk &&
1005 be32_to_cpu(rhead->h_num_logops) == 1) {
1006 umount_data_blk = (i + hblks) % log->l_logBBsize;
1007 error = xlog_bread(log, umount_data_blk, 1, bp, &offset);
1008 if (error)
1009 goto done;
1010
1011 op_head = (xlog_op_header_t *)offset;
1012 if (op_head->oh_flags & XLOG_UNMOUNT_TRANS) {
1013 /*
1014 * Set tail and last sync so that newly written
1015 * log records will point recovery to after the
1016 * current unmount record.
1017 */
1018 xlog_assign_atomic_lsn(&log->l_tail_lsn,
1019 log->l_curr_cycle, after_umount_blk);
1020 xlog_assign_atomic_lsn(&log->l_last_sync_lsn,
1021 log->l_curr_cycle, after_umount_blk);
1022 *tail_blk = after_umount_blk;
1023
1024 /*
1025 * Note that the unmount was clean. If the unmount
1026 * was not clean, we need to know this to rebuild the
1027 * superblock counters from the perag headers if we
1028 * have a filesystem using non-persistent counters.
1029 */
1030 log->l_mp->m_flags |= XFS_MOUNT_WAS_CLEAN;
1031 }
1032 }
1033
1034 /*
1035 * Make sure that there are no blocks in front of the head
1036 * with the same cycle number as the head. This can happen
1037 * because we allow multiple outstanding log writes concurrently,
1038 * and the later writes might make it out before earlier ones.
1039 *
1040 * We use the lsn from before modifying it so that we'll never
1041 * overwrite the unmount record after a clean unmount.
1042 *
1043 * Do this only if we are going to recover the filesystem
1044 *
1045 * NOTE: This used to say "if (!readonly)"
1046 * However on Linux, we can & do recover a read-only filesystem.
1047 * We only skip recovery if NORECOVERY is specified on mount,
1048 * in which case we would not be here.
1049 *
1050 * But... if the -device- itself is readonly, just skip this.
1051 * We can't recover this device anyway, so it won't matter.
1052 */
1053 if (!xfs_readonly_buftarg(log->l_mp->m_logdev_targp))
1054 error = xlog_clear_stale_blocks(log, tail_lsn);
1055
1056done:
1057 xlog_put_bp(bp);
1058
1059 if (error)
1060 xfs_warn(log->l_mp, "failed to locate log tail");
1061 return error;
1062}
1063
1064/*
1065 * Is the log zeroed at all?
1066 *
1067 * The last binary search should be changed to perform an X block read
1068 * once X becomes small enough. You can then search linearly through
1069 * the X blocks. This will cut down on the number of reads we need to do.
1070 *
1071 * If the log is partially zeroed, this routine will pass back the blkno
1072 * of the first block with cycle number 0. It won't have a complete LR
1073 * preceding it.
1074 *
1075 * Return:
1076 * 0 => the log is completely written to
1077 * -1 => use *blk_no as the first block of the log
1078 * >0 => error has occurred
1079 */
1080STATIC int
1081xlog_find_zeroed(
1082 xlog_t *log,
1083 xfs_daddr_t *blk_no)
1084{
1085 xfs_buf_t *bp;
1086 xfs_caddr_t offset;
1087 uint first_cycle, last_cycle;
1088 xfs_daddr_t new_blk, last_blk, start_blk;
1089 xfs_daddr_t num_scan_bblks;
1090 int error, log_bbnum = log->l_logBBsize;
1091
1092 *blk_no = 0;
1093
1094 /* check totally zeroed log */
1095 bp = xlog_get_bp(log, 1);
1096 if (!bp)
1097 return ENOMEM;
1098 error = xlog_bread(log, 0, 1, bp, &offset);
1099 if (error)
1100 goto bp_err;
1101
1102 first_cycle = xlog_get_cycle(offset);
1103 if (first_cycle == 0) { /* completely zeroed log */
1104 *blk_no = 0;
1105 xlog_put_bp(bp);
1106 return -1;
1107 }
1108
1109 /* check partially zeroed log */
1110 error = xlog_bread(log, log_bbnum-1, 1, bp, &offset);
1111 if (error)
1112 goto bp_err;
1113
1114 last_cycle = xlog_get_cycle(offset);
1115 if (last_cycle != 0) { /* log completely written to */
1116 xlog_put_bp(bp);
1117 return 0;
1118 } else if (first_cycle != 1) {
1119 /*
1120 * If the cycle of the last block is zero, the cycle of
1121 * the first block must be 1. If it's not, maybe we're
1122 * not looking at a log... Bail out.
1123 */
1124 xfs_warn(log->l_mp,
1125 "Log inconsistent or not a log (last==0, first!=1)");
1126 return XFS_ERROR(EINVAL);
1127 }
1128
1129 /* we have a partially zeroed log */
1130 last_blk = log_bbnum-1;
1131 if ((error = xlog_find_cycle_start(log, bp, 0, &last_blk, 0)))
1132 goto bp_err;
1133
1134 /*
1135 * Validate the answer. Because there is no way to guarantee that
1136 * the entire log is made up of log records which are the same size,
1137 * we scan over the defined maximum blocks. At this point, the maximum
1138 * is not chosen to mean anything special. XXXmiken
1139 */
1140 num_scan_bblks = XLOG_TOTAL_REC_SHIFT(log);
1141 ASSERT(num_scan_bblks <= INT_MAX);
1142
1143 if (last_blk < num_scan_bblks)
1144 num_scan_bblks = last_blk;
1145 start_blk = last_blk - num_scan_bblks;
1146
1147 /*
1148 * We search for any instances of cycle number 0 that occur before
1149 * our current estimate of the head. What we're trying to detect is
1150 * 1 ... | 0 | 1 | 0...
1151 * ^ binary search ends here
1152 */
1153 if ((error = xlog_find_verify_cycle(log, start_blk,
1154 (int)num_scan_bblks, 0, &new_blk)))
1155 goto bp_err;
1156 if (new_blk != -1)
1157 last_blk = new_blk;
1158
1159 /*
1160 * Potentially backup over partial log record write. We don't need
1161 * to search the end of the log because we know it is zero.
1162 */
1163 if ((error = xlog_find_verify_log_record(log, start_blk,
1164 &last_blk, 0)) == -1) {
1165 error = XFS_ERROR(EIO);
1166 goto bp_err;
1167 } else if (error)
1168 goto bp_err;
1169
1170 *blk_no = last_blk;
1171bp_err:
1172 xlog_put_bp(bp);
1173 if (error)
1174 return error;
1175 return -1;
1176}
1177
1178/*
1179 * These are simple subroutines used by xlog_clear_stale_blocks() below
1180 * to initialize a buffer full of empty log record headers and write
1181 * them into the log.
1182 */
1183STATIC void
1184xlog_add_record(
1185 xlog_t *log,
1186 xfs_caddr_t buf,
1187 int cycle,
1188 int block,
1189 int tail_cycle,
1190 int tail_block)
1191{
1192 xlog_rec_header_t *recp = (xlog_rec_header_t *)buf;
1193
1194 memset(buf, 0, BBSIZE);
1195 recp->h_magicno = cpu_to_be32(XLOG_HEADER_MAGIC_NUM);
1196 recp->h_cycle = cpu_to_be32(cycle);
1197 recp->h_version = cpu_to_be32(
1198 xfs_sb_version_haslogv2(&log->l_mp->m_sb) ? 2 : 1);
1199 recp->h_lsn = cpu_to_be64(xlog_assign_lsn(cycle, block));
1200 recp->h_tail_lsn = cpu_to_be64(xlog_assign_lsn(tail_cycle, tail_block));
1201 recp->h_fmt = cpu_to_be32(XLOG_FMT);
1202 memcpy(&recp->h_fs_uuid, &log->l_mp->m_sb.sb_uuid, sizeof(uuid_t));
1203}
1204
1205STATIC int
1206xlog_write_log_records(
1207 xlog_t *log,
1208 int cycle,
1209 int start_block,
1210 int blocks,
1211 int tail_cycle,
1212 int tail_block)
1213{
1214 xfs_caddr_t offset;
1215 xfs_buf_t *bp;
1216 int balign, ealign;
1217 int sectbb = log->l_sectBBsize;
1218 int end_block = start_block + blocks;
1219 int bufblks;
1220 int error = 0;
1221 int i, j = 0;
1222
1223 /*
1224 * Greedily allocate a buffer big enough to handle the full
1225 * range of basic blocks to be written. If that fails, try
1226 * a smaller size. We need to be able to write at least a
1227 * log sector, or we're out of luck.
1228 */
1229 bufblks = 1 << ffs(blocks);
1230 while (!(bp = xlog_get_bp(log, bufblks))) {
1231 bufblks >>= 1;
1232 if (bufblks < sectbb)
1233 return ENOMEM;
1234 }
1235
1236 /* We may need to do a read at the start to fill in part of
1237 * the buffer in the starting sector not covered by the first
1238 * write below.
1239 */
1240 balign = round_down(start_block, sectbb);
1241 if (balign != start_block) {
1242 error = xlog_bread_noalign(log, start_block, 1, bp);
1243 if (error)
1244 goto out_put_bp;
1245
1246 j = start_block - balign;
1247 }
1248
1249 for (i = start_block; i < end_block; i += bufblks) {
1250 int bcount, endcount;
1251
1252 bcount = min(bufblks, end_block - start_block);
1253 endcount = bcount - j;
1254
1255 /* We may need to do a read at the end to fill in part of
1256 * the buffer in the final sector not covered by the write.
1257 * If this is the same sector as the above read, skip it.
1258 */
1259 ealign = round_down(end_block, sectbb);
1260 if (j == 0 && (start_block + endcount > ealign)) {
1261 offset = bp->b_addr + BBTOB(ealign - start_block);
1262 error = xlog_bread_offset(log, ealign, sectbb,
1263 bp, offset);
1264 if (error)
1265 break;
1266
1267 }
1268
1269 offset = xlog_align(log, start_block, endcount, bp);
1270 for (; j < endcount; j++) {
1271 xlog_add_record(log, offset, cycle, i+j,
1272 tail_cycle, tail_block);
1273 offset += BBSIZE;
1274 }
1275 error = xlog_bwrite(log, start_block, endcount, bp);
1276 if (error)
1277 break;
1278 start_block += endcount;
1279 j = 0;
1280 }
1281
1282 out_put_bp:
1283 xlog_put_bp(bp);
1284 return error;
1285}
1286
1287/*
1288 * This routine is called to blow away any incomplete log writes out
1289 * in front of the log head. We do this so that we won't become confused
1290 * if we come up, write only a little bit more, and then crash again.
1291 * If we leave the partial log records out there, this situation could
1292 * cause us to think those partial writes are valid blocks since they
1293 * have the current cycle number. We get rid of them by overwriting them
1294 * with empty log records with the old cycle number rather than the
1295 * current one.
1296 *
1297 * The tail lsn is passed in rather than taken from
1298 * the log so that we will not write over the unmount record after a
1299 * clean unmount in a 512 block log. Doing so would leave the log without
1300 * any valid log records in it until a new one was written. If we crashed
1301 * during that time we would not be able to recover.
1302 */
1303STATIC int
1304xlog_clear_stale_blocks(
1305 xlog_t *log,
1306 xfs_lsn_t tail_lsn)
1307{
1308 int tail_cycle, head_cycle;
1309 int tail_block, head_block;
1310 int tail_distance, max_distance;
1311 int distance;
1312 int error;
1313
1314 tail_cycle = CYCLE_LSN(tail_lsn);
1315 tail_block = BLOCK_LSN(tail_lsn);
1316 head_cycle = log->l_curr_cycle;
1317 head_block = log->l_curr_block;
1318
1319 /*
1320 * Figure out the distance between the new head of the log
1321 * and the tail. We want to write over any blocks beyond the
1322 * head that we may have written just before the crash, but
1323 * we don't want to overwrite the tail of the log.
1324 */
1325 if (head_cycle == tail_cycle) {
1326 /*
1327 * The tail is behind the head in the physical log,
1328 * so the distance from the head to the tail is the
1329 * distance from the head to the end of the log plus
1330 * the distance from the beginning of the log to the
1331 * tail.
1332 */
1333 if (unlikely(head_block < tail_block || head_block >= log->l_logBBsize)) {
1334 XFS_ERROR_REPORT("xlog_clear_stale_blocks(1)",
1335 XFS_ERRLEVEL_LOW, log->l_mp);
1336 return XFS_ERROR(EFSCORRUPTED);
1337 }
1338 tail_distance = tail_block + (log->l_logBBsize - head_block);
1339 } else {
1340 /*
1341 * The head is behind the tail in the physical log,
1342 * so the distance from the head to the tail is just
1343 * the tail block minus the head block.
1344 */
1345 if (unlikely(head_block >= tail_block || head_cycle != (tail_cycle + 1))){
1346 XFS_ERROR_REPORT("xlog_clear_stale_blocks(2)",
1347 XFS_ERRLEVEL_LOW, log->l_mp);
1348 return XFS_ERROR(EFSCORRUPTED);
1349 }
1350 tail_distance = tail_block - head_block;
1351 }
1352
1353 /*
1354 * If the head is right up against the tail, we can't clear
1355 * anything.
1356 */
1357 if (tail_distance <= 0) {
1358 ASSERT(tail_distance == 0);
1359 return 0;
1360 }
1361
1362 max_distance = XLOG_TOTAL_REC_SHIFT(log);
1363 /*
1364 * Take the smaller of the maximum amount of outstanding I/O
1365 * we could have and the distance to the tail to clear out.
1366 * We take the smaller so that we don't overwrite the tail and
1367 * we don't waste all day writing from the head to the tail
1368 * for no reason.
1369 */
1370 max_distance = MIN(max_distance, tail_distance);
1371
1372 if ((head_block + max_distance) <= log->l_logBBsize) {
1373 /*
1374 * We can stomp all the blocks we need to without
1375 * wrapping around the end of the log. Just do it
1376 * in a single write. Use the cycle number of the
1377 * current cycle minus one so that the log will look like:
1378 * n ... | n - 1 ...
1379 */
1380 error = xlog_write_log_records(log, (head_cycle - 1),
1381 head_block, max_distance, tail_cycle,
1382 tail_block);
1383 if (error)
1384 return error;
1385 } else {
1386 /*
1387 * We need to wrap around the end of the physical log in
1388 * order to clear all the blocks. Do it in two separate
1389 * I/Os. The first write should be from the head to the
1390 * end of the physical log, and it should use the current
1391 * cycle number minus one just like above.
1392 */
1393 distance = log->l_logBBsize - head_block;
1394 error = xlog_write_log_records(log, (head_cycle - 1),
1395 head_block, distance, tail_cycle,
1396 tail_block);
1397
1398 if (error)
1399 return error;
1400
1401 /*
1402 * Now write the blocks at the start of the physical log.
1403 * This writes the remainder of the blocks we want to clear.
1404 * It uses the current cycle number since we're now on the
1405 * same cycle as the head so that we get:
1406 * n ... n ... | n - 1 ...
1407 * ^^^^^ blocks we're writing
1408 */
1409 distance = max_distance - (log->l_logBBsize - head_block);
1410 error = xlog_write_log_records(log, head_cycle, 0, distance,
1411 tail_cycle, tail_block);
1412 if (error)
1413 return error;
1414 }
1415
1416 return 0;
1417}
1418
1419/******************************************************************************
1420 *
1421 * Log recover routines
1422 *
1423 ******************************************************************************
1424 */
1425
1426STATIC xlog_recover_t *
1427xlog_recover_find_tid(
1428 struct hlist_head *head,
1429 xlog_tid_t tid)
1430{
1431 xlog_recover_t *trans;
1432 struct hlist_node *n;
1433
1434 hlist_for_each_entry(trans, n, head, r_list) {
1435 if (trans->r_log_tid == tid)
1436 return trans;
1437 }
1438 return NULL;
1439}
1440
1441STATIC void
1442xlog_recover_new_tid(
1443 struct hlist_head *head,
1444 xlog_tid_t tid,
1445 xfs_lsn_t lsn)
1446{
1447 xlog_recover_t *trans;
1448
1449 trans = kmem_zalloc(sizeof(xlog_recover_t), KM_SLEEP);
1450 trans->r_log_tid = tid;
1451 trans->r_lsn = lsn;
1452 INIT_LIST_HEAD(&trans->r_itemq);
1453
1454 INIT_HLIST_NODE(&trans->r_list);
1455 hlist_add_head(&trans->r_list, head);
1456}
1457
1458STATIC void
1459xlog_recover_add_item(
1460 struct list_head *head)
1461{
1462 xlog_recover_item_t *item;
1463
1464 item = kmem_zalloc(sizeof(xlog_recover_item_t), KM_SLEEP);
1465 INIT_LIST_HEAD(&item->ri_list);
1466 list_add_tail(&item->ri_list, head);
1467}
1468
1469STATIC int
1470xlog_recover_add_to_cont_trans(
1471 struct log *log,
1472 xlog_recover_t *trans,
1473 xfs_caddr_t dp,
1474 int len)
1475{
1476 xlog_recover_item_t *item;
1477 xfs_caddr_t ptr, old_ptr;
1478 int old_len;
1479
1480 if (list_empty(&trans->r_itemq)) {
1481 /* finish copying rest of trans header */
1482 xlog_recover_add_item(&trans->r_itemq);
1483 ptr = (xfs_caddr_t) &trans->r_theader +
1484 sizeof(xfs_trans_header_t) - len;
1485 memcpy(ptr, dp, len); /* d, s, l */
1486 return 0;
1487 }
1488 /* take the tail entry */
1489 item = list_entry(trans->r_itemq.prev, xlog_recover_item_t, ri_list);
1490
1491 old_ptr = item->ri_buf[item->ri_cnt-1].i_addr;
1492 old_len = item->ri_buf[item->ri_cnt-1].i_len;
1493
1494 ptr = kmem_realloc(old_ptr, len+old_len, old_len, 0u);
1495 memcpy(&ptr[old_len], dp, len); /* d, s, l */
1496 item->ri_buf[item->ri_cnt-1].i_len += len;
1497 item->ri_buf[item->ri_cnt-1].i_addr = ptr;
1498 trace_xfs_log_recover_item_add_cont(log, trans, item, 0);
1499 return 0;
1500}
1501
1502/*
1503 * The next region to add is the start of a new region. It could be
1504 * a whole region or it could be the first part of a new region. Because
1505 * of this, the assumption here is that the type and size fields of all
1506 * format structures fit into the first 32 bits of the structure.
1507 *
1508 * This works because all regions must be 32 bit aligned. Therefore, we
1509 * either have both fields or we have neither field. In the case we have
1510 * neither field, the data part of the region is zero length. We only have
1511 * a log_op_header and can throw away the header since a new one will appear
1512 * later. If we have at least 4 bytes, then we can determine how many regions
1513 * will appear in the current log item.
1514 */
1515STATIC int
1516xlog_recover_add_to_trans(
1517 struct log *log,
1518 xlog_recover_t *trans,
1519 xfs_caddr_t dp,
1520 int len)
1521{
1522 xfs_inode_log_format_t *in_f; /* any will do */
1523 xlog_recover_item_t *item;
1524 xfs_caddr_t ptr;
1525
1526 if (!len)
1527 return 0;
1528 if (list_empty(&trans->r_itemq)) {
1529 /* we need to catch log corruptions here */
1530 if (*(uint *)dp != XFS_TRANS_HEADER_MAGIC) {
1531 xfs_warn(log->l_mp, "%s: bad header magic number",
1532 __func__);
1533 ASSERT(0);
1534 return XFS_ERROR(EIO);
1535 }
1536 if (len == sizeof(xfs_trans_header_t))
1537 xlog_recover_add_item(&trans->r_itemq);
1538 memcpy(&trans->r_theader, dp, len); /* d, s, l */
1539 return 0;
1540 }
1541
1542 ptr = kmem_alloc(len, KM_SLEEP);
1543 memcpy(ptr, dp, len);
1544 in_f = (xfs_inode_log_format_t *)ptr;
1545
1546 /* take the tail entry */
1547 item = list_entry(trans->r_itemq.prev, xlog_recover_item_t, ri_list);
1548 if (item->ri_total != 0 &&
1549 item->ri_total == item->ri_cnt) {
1550 /* tail item is in use, get a new one */
1551 xlog_recover_add_item(&trans->r_itemq);
1552 item = list_entry(trans->r_itemq.prev,
1553 xlog_recover_item_t, ri_list);
1554 }
1555
1556 if (item->ri_total == 0) { /* first region to be added */
1557 if (in_f->ilf_size == 0 ||
1558 in_f->ilf_size > XLOG_MAX_REGIONS_IN_ITEM) {
1559 xfs_warn(log->l_mp,
1560 "bad number of regions (%d) in inode log format",
1561 in_f->ilf_size);
1562 ASSERT(0);
1563 return XFS_ERROR(EIO);
1564 }
1565
1566 item->ri_total = in_f->ilf_size;
1567 item->ri_buf =
1568 kmem_zalloc(item->ri_total * sizeof(xfs_log_iovec_t),
1569 KM_SLEEP);
1570 }
1571 ASSERT(item->ri_total > item->ri_cnt);
1572 /* Description region is ri_buf[0] */
1573 item->ri_buf[item->ri_cnt].i_addr = ptr;
1574 item->ri_buf[item->ri_cnt].i_len = len;
1575 item->ri_cnt++;
1576 trace_xfs_log_recover_item_add(log, trans, item, 0);
1577 return 0;
1578}
1579
1580/*
1581 * Sort the log items in the transaction. Cancelled buffers need
1582 * to be put first so they are processed before any items that might
1583 * modify the buffers. If they are cancelled, then the modifications
1584 * don't need to be replayed.
1585 */
1586STATIC int
1587xlog_recover_reorder_trans(
1588 struct log *log,
1589 xlog_recover_t *trans,
1590 int pass)
1591{
1592 xlog_recover_item_t *item, *n;
1593 LIST_HEAD(sort_list);
1594
1595 list_splice_init(&trans->r_itemq, &sort_list);
1596 list_for_each_entry_safe(item, n, &sort_list, ri_list) {
1597 xfs_buf_log_format_t *buf_f = item->ri_buf[0].i_addr;
1598
1599 switch (ITEM_TYPE(item)) {
1600 case XFS_LI_BUF:
1601 if (!(buf_f->blf_flags & XFS_BLF_CANCEL)) {
1602 trace_xfs_log_recover_item_reorder_head(log,
1603 trans, item, pass);
1604 list_move(&item->ri_list, &trans->r_itemq);
1605 break;
1606 }
1607 case XFS_LI_INODE:
1608 case XFS_LI_DQUOT:
1609 case XFS_LI_QUOTAOFF:
1610 case XFS_LI_EFD:
1611 case XFS_LI_EFI:
1612 trace_xfs_log_recover_item_reorder_tail(log,
1613 trans, item, pass);
1614 list_move_tail(&item->ri_list, &trans->r_itemq);
1615 break;
1616 default:
1617 xfs_warn(log->l_mp,
1618 "%s: unrecognized type of log operation",
1619 __func__);
1620 ASSERT(0);
1621 return XFS_ERROR(EIO);
1622 }
1623 }
1624 ASSERT(list_empty(&sort_list));
1625 return 0;
1626}
1627
1628/*
1629 * Build up the table of buf cancel records so that we don't replay
1630 * cancelled data in the second pass. For buffer records that are
1631 * not cancel records, there is nothing to do here so we just return.
1632 *
1633 * If we get a cancel record which is already in the table, this indicates
1634 * that the buffer was cancelled multiple times. In order to ensure
1635 * that during pass 2 we keep the record in the table until we reach its
1636 * last occurrence in the log, we keep a reference count in the cancel
1637 * record in the table to tell us how many times we expect to see this
1638 * record during the second pass.
1639 */
1640STATIC int
1641xlog_recover_buffer_pass1(
1642 struct log *log,
1643 xlog_recover_item_t *item)
1644{
1645 xfs_buf_log_format_t *buf_f = item->ri_buf[0].i_addr;
1646 struct list_head *bucket;
1647 struct xfs_buf_cancel *bcp;
1648
1649 /*
1650 * If this isn't a cancel buffer item, then just return.
1651 */
1652 if (!(buf_f->blf_flags & XFS_BLF_CANCEL)) {
1653 trace_xfs_log_recover_buf_not_cancel(log, buf_f);
1654 return 0;
1655 }
1656
1657 /*
1658 * Insert an xfs_buf_cancel record into the hash table of them.
1659 * If there is already an identical record, bump its reference count.
1660 */
1661 bucket = XLOG_BUF_CANCEL_BUCKET(log, buf_f->blf_blkno);
1662 list_for_each_entry(bcp, bucket, bc_list) {
1663 if (bcp->bc_blkno == buf_f->blf_blkno &&
1664 bcp->bc_len == buf_f->blf_len) {
1665 bcp->bc_refcount++;
1666 trace_xfs_log_recover_buf_cancel_ref_inc(log, buf_f);
1667 return 0;
1668 }
1669 }
1670
1671 bcp = kmem_alloc(sizeof(struct xfs_buf_cancel), KM_SLEEP);
1672 bcp->bc_blkno = buf_f->blf_blkno;
1673 bcp->bc_len = buf_f->blf_len;
1674 bcp->bc_refcount = 1;
1675 list_add_tail(&bcp->bc_list, bucket);
1676
1677 trace_xfs_log_recover_buf_cancel_add(log, buf_f);
1678 return 0;
1679}
1680
1681/*
1682 * Check to see whether the buffer being recovered has a corresponding
1683 * entry in the buffer cancel record table. If it does then return 1
1684 * so that it will be cancelled, otherwise return 0. If the buffer is
1685 * actually a buffer cancel item (XFS_BLF_CANCEL is set), then decrement
1686 * the refcount on the entry in the table and remove it from the table
1687 * if this is the last reference.
1688 *
1689 * We remove the cancel record from the table when we encounter its
1690 * last occurrence in the log so that if the same buffer is re-used
1691 * again after its last cancellation we actually replay the changes
1692 * made at that point.
1693 */
1694STATIC int
1695xlog_check_buffer_cancelled(
1696 struct log *log,
1697 xfs_daddr_t blkno,
1698 uint len,
1699 ushort flags)
1700{
1701 struct list_head *bucket;
1702 struct xfs_buf_cancel *bcp;
1703
1704 if (log->l_buf_cancel_table == NULL) {
1705 /*
1706 * There is nothing in the table built in pass one,
1707 * so this buffer must not be cancelled.
1708 */
1709 ASSERT(!(flags & XFS_BLF_CANCEL));
1710 return 0;
1711 }
1712
1713 /*
1714 * Search for an entry in the cancel table that matches our buffer.
1715 */
1716 bucket = XLOG_BUF_CANCEL_BUCKET(log, blkno);
1717 list_for_each_entry(bcp, bucket, bc_list) {
1718 if (bcp->bc_blkno == blkno && bcp->bc_len == len)
1719 goto found;
1720 }
1721
1722 /*
1723 * We didn't find a corresponding entry in the table, so return 0 so
1724 * that the buffer is NOT cancelled.
1725 */
1726 ASSERT(!(flags & XFS_BLF_CANCEL));
1727 return 0;
1728
1729found:
1730 /*
1731 * We've go a match, so return 1 so that the recovery of this buffer
1732 * is cancelled. If this buffer is actually a buffer cancel log
1733 * item, then decrement the refcount on the one in the table and
1734 * remove it if this is the last reference.
1735 */
1736 if (flags & XFS_BLF_CANCEL) {
1737 if (--bcp->bc_refcount == 0) {
1738 list_del(&bcp->bc_list);
1739 kmem_free(bcp);
1740 }
1741 }
1742 return 1;
1743}
1744
1745/*
1746 * Perform recovery for a buffer full of inodes. In these buffers, the only
1747 * data which should be recovered is that which corresponds to the
1748 * di_next_unlinked pointers in the on disk inode structures. The rest of the
1749 * data for the inodes is always logged through the inodes themselves rather
1750 * than the inode buffer and is recovered in xlog_recover_inode_pass2().
1751 *
1752 * The only time when buffers full of inodes are fully recovered is when the
1753 * buffer is full of newly allocated inodes. In this case the buffer will
1754 * not be marked as an inode buffer and so will be sent to
1755 * xlog_recover_do_reg_buffer() below during recovery.
1756 */
1757STATIC int
1758xlog_recover_do_inode_buffer(
1759 struct xfs_mount *mp,
1760 xlog_recover_item_t *item,
1761 struct xfs_buf *bp,
1762 xfs_buf_log_format_t *buf_f)
1763{
1764 int i;
1765 int item_index = 0;
1766 int bit = 0;
1767 int nbits = 0;
1768 int reg_buf_offset = 0;
1769 int reg_buf_bytes = 0;
1770 int next_unlinked_offset;
1771 int inodes_per_buf;
1772 xfs_agino_t *logged_nextp;
1773 xfs_agino_t *buffer_nextp;
1774
1775 trace_xfs_log_recover_buf_inode_buf(mp->m_log, buf_f);
1776
1777 inodes_per_buf = XFS_BUF_COUNT(bp) >> mp->m_sb.sb_inodelog;
1778 for (i = 0; i < inodes_per_buf; i++) {
1779 next_unlinked_offset = (i * mp->m_sb.sb_inodesize) +
1780 offsetof(xfs_dinode_t, di_next_unlinked);
1781
1782 while (next_unlinked_offset >=
1783 (reg_buf_offset + reg_buf_bytes)) {
1784 /*
1785 * The next di_next_unlinked field is beyond
1786 * the current logged region. Find the next
1787 * logged region that contains or is beyond
1788 * the current di_next_unlinked field.
1789 */
1790 bit += nbits;
1791 bit = xfs_next_bit(buf_f->blf_data_map,
1792 buf_f->blf_map_size, bit);
1793
1794 /*
1795 * If there are no more logged regions in the
1796 * buffer, then we're done.
1797 */
1798 if (bit == -1)
1799 return 0;
1800
1801 nbits = xfs_contig_bits(buf_f->blf_data_map,
1802 buf_f->blf_map_size, bit);
1803 ASSERT(nbits > 0);
1804 reg_buf_offset = bit << XFS_BLF_SHIFT;
1805 reg_buf_bytes = nbits << XFS_BLF_SHIFT;
1806 item_index++;
1807 }
1808
1809 /*
1810 * If the current logged region starts after the current
1811 * di_next_unlinked field, then move on to the next
1812 * di_next_unlinked field.
1813 */
1814 if (next_unlinked_offset < reg_buf_offset)
1815 continue;
1816
1817 ASSERT(item->ri_buf[item_index].i_addr != NULL);
1818 ASSERT((item->ri_buf[item_index].i_len % XFS_BLF_CHUNK) == 0);
1819 ASSERT((reg_buf_offset + reg_buf_bytes) <= XFS_BUF_COUNT(bp));
1820
1821 /*
1822 * The current logged region contains a copy of the
1823 * current di_next_unlinked field. Extract its value
1824 * and copy it to the buffer copy.
1825 */
1826 logged_nextp = item->ri_buf[item_index].i_addr +
1827 next_unlinked_offset - reg_buf_offset;
1828 if (unlikely(*logged_nextp == 0)) {
1829 xfs_alert(mp,
1830 "Bad inode buffer log record (ptr = 0x%p, bp = 0x%p). "
1831 "Trying to replay bad (0) inode di_next_unlinked field.",
1832 item, bp);
1833 XFS_ERROR_REPORT("xlog_recover_do_inode_buf",
1834 XFS_ERRLEVEL_LOW, mp);
1835 return XFS_ERROR(EFSCORRUPTED);
1836 }
1837
1838 buffer_nextp = (xfs_agino_t *)xfs_buf_offset(bp,
1839 next_unlinked_offset);
1840 *buffer_nextp = *logged_nextp;
1841 }
1842
1843 return 0;
1844}
1845
1846/*
1847 * Perform a 'normal' buffer recovery. Each logged region of the
1848 * buffer should be copied over the corresponding region in the
1849 * given buffer. The bitmap in the buf log format structure indicates
1850 * where to place the logged data.
1851 */
1852STATIC void
1853xlog_recover_do_reg_buffer(
1854 struct xfs_mount *mp,
1855 xlog_recover_item_t *item,
1856 struct xfs_buf *bp,
1857 xfs_buf_log_format_t *buf_f)
1858{
1859 int i;
1860 int bit;
1861 int nbits;
1862 int error;
1863
1864 trace_xfs_log_recover_buf_reg_buf(mp->m_log, buf_f);
1865
1866 bit = 0;
1867 i = 1; /* 0 is the buf format structure */
1868 while (1) {
1869 bit = xfs_next_bit(buf_f->blf_data_map,
1870 buf_f->blf_map_size, bit);
1871 if (bit == -1)
1872 break;
1873 nbits = xfs_contig_bits(buf_f->blf_data_map,
1874 buf_f->blf_map_size, bit);
1875 ASSERT(nbits > 0);
1876 ASSERT(item->ri_buf[i].i_addr != NULL);
1877 ASSERT(item->ri_buf[i].i_len % XFS_BLF_CHUNK == 0);
1878 ASSERT(XFS_BUF_COUNT(bp) >=
1879 ((uint)bit << XFS_BLF_SHIFT)+(nbits<<XFS_BLF_SHIFT));
1880
1881 /*
1882 * Do a sanity check if this is a dquot buffer. Just checking
1883 * the first dquot in the buffer should do. XXXThis is
1884 * probably a good thing to do for other buf types also.
1885 */
1886 error = 0;
1887 if (buf_f->blf_flags &
1888 (XFS_BLF_UDQUOT_BUF|XFS_BLF_PDQUOT_BUF|XFS_BLF_GDQUOT_BUF)) {
1889 if (item->ri_buf[i].i_addr == NULL) {
1890 xfs_alert(mp,
1891 "XFS: NULL dquot in %s.", __func__);
1892 goto next;
1893 }
1894 if (item->ri_buf[i].i_len < sizeof(xfs_disk_dquot_t)) {
1895 xfs_alert(mp,
1896 "XFS: dquot too small (%d) in %s.",
1897 item->ri_buf[i].i_len, __func__);
1898 goto next;
1899 }
1900 error = xfs_qm_dqcheck(mp, item->ri_buf[i].i_addr,
1901 -1, 0, XFS_QMOPT_DOWARN,
1902 "dquot_buf_recover");
1903 if (error)
1904 goto next;
1905 }
1906
1907 memcpy(xfs_buf_offset(bp,
1908 (uint)bit << XFS_BLF_SHIFT), /* dest */
1909 item->ri_buf[i].i_addr, /* source */
1910 nbits<<XFS_BLF_SHIFT); /* length */
1911 next:
1912 i++;
1913 bit += nbits;
1914 }
1915
1916 /* Shouldn't be any more regions */
1917 ASSERT(i == item->ri_total);
1918}
1919
1920/*
1921 * Do some primitive error checking on ondisk dquot data structures.
1922 */
1923int
1924xfs_qm_dqcheck(
1925 struct xfs_mount *mp,
1926 xfs_disk_dquot_t *ddq,
1927 xfs_dqid_t id,
1928 uint type, /* used only when IO_dorepair is true */
1929 uint flags,
1930 char *str)
1931{
1932 xfs_dqblk_t *d = (xfs_dqblk_t *)ddq;
1933 int errs = 0;
1934
1935 /*
1936 * We can encounter an uninitialized dquot buffer for 2 reasons:
1937 * 1. If we crash while deleting the quotainode(s), and those blks got
1938 * used for user data. This is because we take the path of regular
1939 * file deletion; however, the size field of quotainodes is never
1940 * updated, so all the tricks that we play in itruncate_finish
1941 * don't quite matter.
1942 *
1943 * 2. We don't play the quota buffers when there's a quotaoff logitem.
1944 * But the allocation will be replayed so we'll end up with an
1945 * uninitialized quota block.
1946 *
1947 * This is all fine; things are still consistent, and we haven't lost
1948 * any quota information. Just don't complain about bad dquot blks.
1949 */
1950 if (ddq->d_magic != cpu_to_be16(XFS_DQUOT_MAGIC)) {
1951 if (flags & XFS_QMOPT_DOWARN)
1952 xfs_alert(mp,
1953 "%s : XFS dquot ID 0x%x, magic 0x%x != 0x%x",
1954 str, id, be16_to_cpu(ddq->d_magic), XFS_DQUOT_MAGIC);
1955 errs++;
1956 }
1957 if (ddq->d_version != XFS_DQUOT_VERSION) {
1958 if (flags & XFS_QMOPT_DOWARN)
1959 xfs_alert(mp,
1960 "%s : XFS dquot ID 0x%x, version 0x%x != 0x%x",
1961 str, id, ddq->d_version, XFS_DQUOT_VERSION);
1962 errs++;
1963 }
1964
1965 if (ddq->d_flags != XFS_DQ_USER &&
1966 ddq->d_flags != XFS_DQ_PROJ &&
1967 ddq->d_flags != XFS_DQ_GROUP) {
1968 if (flags & XFS_QMOPT_DOWARN)
1969 xfs_alert(mp,
1970 "%s : XFS dquot ID 0x%x, unknown flags 0x%x",
1971 str, id, ddq->d_flags);
1972 errs++;
1973 }
1974
1975 if (id != -1 && id != be32_to_cpu(ddq->d_id)) {
1976 if (flags & XFS_QMOPT_DOWARN)
1977 xfs_alert(mp,
1978 "%s : ondisk-dquot 0x%p, ID mismatch: "
1979 "0x%x expected, found id 0x%x",
1980 str, ddq, id, be32_to_cpu(ddq->d_id));
1981 errs++;
1982 }
1983
1984 if (!errs && ddq->d_id) {
1985 if (ddq->d_blk_softlimit &&
1986 be64_to_cpu(ddq->d_bcount) >=
1987 be64_to_cpu(ddq->d_blk_softlimit)) {
1988 if (!ddq->d_btimer) {
1989 if (flags & XFS_QMOPT_DOWARN)
1990 xfs_alert(mp,
1991 "%s : Dquot ID 0x%x (0x%p) BLK TIMER NOT STARTED",
1992 str, (int)be32_to_cpu(ddq->d_id), ddq);
1993 errs++;
1994 }
1995 }
1996 if (ddq->d_ino_softlimit &&
1997 be64_to_cpu(ddq->d_icount) >=
1998 be64_to_cpu(ddq->d_ino_softlimit)) {
1999 if (!ddq->d_itimer) {
2000 if (flags & XFS_QMOPT_DOWARN)
2001 xfs_alert(mp,
2002 "%s : Dquot ID 0x%x (0x%p) INODE TIMER NOT STARTED",
2003 str, (int)be32_to_cpu(ddq->d_id), ddq);
2004 errs++;
2005 }
2006 }
2007 if (ddq->d_rtb_softlimit &&
2008 be64_to_cpu(ddq->d_rtbcount) >=
2009 be64_to_cpu(ddq->d_rtb_softlimit)) {
2010 if (!ddq->d_rtbtimer) {
2011 if (flags & XFS_QMOPT_DOWARN)
2012 xfs_alert(mp,
2013 "%s : Dquot ID 0x%x (0x%p) RTBLK TIMER NOT STARTED",
2014 str, (int)be32_to_cpu(ddq->d_id), ddq);
2015 errs++;
2016 }
2017 }
2018 }
2019
2020 if (!errs || !(flags & XFS_QMOPT_DQREPAIR))
2021 return errs;
2022
2023 if (flags & XFS_QMOPT_DOWARN)
2024 xfs_notice(mp, "Re-initializing dquot ID 0x%x", id);
2025
2026 /*
2027 * Typically, a repair is only requested by quotacheck.
2028 */
2029 ASSERT(id != -1);
2030 ASSERT(flags & XFS_QMOPT_DQREPAIR);
2031 memset(d, 0, sizeof(xfs_dqblk_t));
2032
2033 d->dd_diskdq.d_magic = cpu_to_be16(XFS_DQUOT_MAGIC);
2034 d->dd_diskdq.d_version = XFS_DQUOT_VERSION;
2035 d->dd_diskdq.d_flags = type;
2036 d->dd_diskdq.d_id = cpu_to_be32(id);
2037
2038 return errs;
2039}
2040
2041/*
2042 * Perform a dquot buffer recovery.
2043 * Simple algorithm: if we have found a QUOTAOFF logitem of the same type
2044 * (ie. USR or GRP), then just toss this buffer away; don't recover it.
2045 * Else, treat it as a regular buffer and do recovery.
2046 */
2047STATIC void
2048xlog_recover_do_dquot_buffer(
2049 xfs_mount_t *mp,
2050 xlog_t *log,
2051 xlog_recover_item_t *item,
2052 xfs_buf_t *bp,
2053 xfs_buf_log_format_t *buf_f)
2054{
2055 uint type;
2056
2057 trace_xfs_log_recover_buf_dquot_buf(log, buf_f);
2058
2059 /*
2060 * Filesystems are required to send in quota flags at mount time.
2061 */
2062 if (mp->m_qflags == 0) {
2063 return;
2064 }
2065
2066 type = 0;
2067 if (buf_f->blf_flags & XFS_BLF_UDQUOT_BUF)
2068 type |= XFS_DQ_USER;
2069 if (buf_f->blf_flags & XFS_BLF_PDQUOT_BUF)
2070 type |= XFS_DQ_PROJ;
2071 if (buf_f->blf_flags & XFS_BLF_GDQUOT_BUF)
2072 type |= XFS_DQ_GROUP;
2073 /*
2074 * This type of quotas was turned off, so ignore this buffer
2075 */
2076 if (log->l_quotaoffs_flag & type)
2077 return;
2078
2079 xlog_recover_do_reg_buffer(mp, item, bp, buf_f);
2080}
2081
2082/*
2083 * This routine replays a modification made to a buffer at runtime.
2084 * There are actually two types of buffer, regular and inode, which
2085 * are handled differently. Inode buffers are handled differently
2086 * in that we only recover a specific set of data from them, namely
2087 * the inode di_next_unlinked fields. This is because all other inode
2088 * data is actually logged via inode records and any data we replay
2089 * here which overlaps that may be stale.
2090 *
2091 * When meta-data buffers are freed at run time we log a buffer item
2092 * with the XFS_BLF_CANCEL bit set to indicate that previous copies
2093 * of the buffer in the log should not be replayed at recovery time.
2094 * This is so that if the blocks covered by the buffer are reused for
2095 * file data before we crash we don't end up replaying old, freed
2096 * meta-data into a user's file.
2097 *
2098 * To handle the cancellation of buffer log items, we make two passes
2099 * over the log during recovery. During the first we build a table of
2100 * those buffers which have been cancelled, and during the second we
2101 * only replay those buffers which do not have corresponding cancel
2102 * records in the table. See xlog_recover_do_buffer_pass[1,2] above
2103 * for more details on the implementation of the table of cancel records.
2104 */
2105STATIC int
2106xlog_recover_buffer_pass2(
2107 xlog_t *log,
2108 xlog_recover_item_t *item)
2109{
2110 xfs_buf_log_format_t *buf_f = item->ri_buf[0].i_addr;
2111 xfs_mount_t *mp = log->l_mp;
2112 xfs_buf_t *bp;
2113 int error;
2114 uint buf_flags;
2115
2116 /*
2117 * In this pass we only want to recover all the buffers which have
2118 * not been cancelled and are not cancellation buffers themselves.
2119 */
2120 if (xlog_check_buffer_cancelled(log, buf_f->blf_blkno,
2121 buf_f->blf_len, buf_f->blf_flags)) {
2122 trace_xfs_log_recover_buf_cancel(log, buf_f);
2123 return 0;
2124 }
2125
2126 trace_xfs_log_recover_buf_recover(log, buf_f);
2127
2128 buf_flags = XBF_LOCK;
2129 if (!(buf_f->blf_flags & XFS_BLF_INODE_BUF))
2130 buf_flags |= XBF_MAPPED;
2131
2132 bp = xfs_buf_read(mp->m_ddev_targp, buf_f->blf_blkno, buf_f->blf_len,
2133 buf_flags);
2134 if (!bp)
2135 return XFS_ERROR(ENOMEM);
2136 error = bp->b_error;
2137 if (error) {
2138 xfs_ioerror_alert("xlog_recover_do..(read#1)", mp,
2139 bp, buf_f->blf_blkno);
2140 xfs_buf_relse(bp);
2141 return error;
2142 }
2143
2144 if (buf_f->blf_flags & XFS_BLF_INODE_BUF) {
2145 error = xlog_recover_do_inode_buffer(mp, item, bp, buf_f);
2146 } else if (buf_f->blf_flags &
2147 (XFS_BLF_UDQUOT_BUF|XFS_BLF_PDQUOT_BUF|XFS_BLF_GDQUOT_BUF)) {
2148 xlog_recover_do_dquot_buffer(mp, log, item, bp, buf_f);
2149 } else {
2150 xlog_recover_do_reg_buffer(mp, item, bp, buf_f);
2151 }
2152 if (error)
2153 return XFS_ERROR(error);
2154
2155 /*
2156 * Perform delayed write on the buffer. Asynchronous writes will be
2157 * slower when taking into account all the buffers to be flushed.
2158 *
2159 * Also make sure that only inode buffers with good sizes stay in
2160 * the buffer cache. The kernel moves inodes in buffers of 1 block
2161 * or XFS_INODE_CLUSTER_SIZE bytes, whichever is bigger. The inode
2162 * buffers in the log can be a different size if the log was generated
2163 * by an older kernel using unclustered inode buffers or a newer kernel
2164 * running with a different inode cluster size. Regardless, if the
2165 * the inode buffer size isn't MAX(blocksize, XFS_INODE_CLUSTER_SIZE)
2166 * for *our* value of XFS_INODE_CLUSTER_SIZE, then we need to keep
2167 * the buffer out of the buffer cache so that the buffer won't
2168 * overlap with future reads of those inodes.
2169 */
2170 if (XFS_DINODE_MAGIC ==
2171 be16_to_cpu(*((__be16 *)xfs_buf_offset(bp, 0))) &&
2172 (XFS_BUF_COUNT(bp) != MAX(log->l_mp->m_sb.sb_blocksize,
2173 (__uint32_t)XFS_INODE_CLUSTER_SIZE(log->l_mp)))) {
2174 XFS_BUF_STALE(bp);
2175 error = xfs_bwrite(mp, bp);
2176 } else {
2177 ASSERT(bp->b_target->bt_mount == mp);
2178 bp->b_iodone = xlog_recover_iodone;
2179 xfs_bdwrite(mp, bp);
2180 }
2181
2182 return (error);
2183}
2184
2185STATIC int
2186xlog_recover_inode_pass2(
2187 xlog_t *log,
2188 xlog_recover_item_t *item)
2189{
2190 xfs_inode_log_format_t *in_f;
2191 xfs_mount_t *mp = log->l_mp;
2192 xfs_buf_t *bp;
2193 xfs_dinode_t *dip;
2194 int len;
2195 xfs_caddr_t src;
2196 xfs_caddr_t dest;
2197 int error;
2198 int attr_index;
2199 uint fields;
2200 xfs_icdinode_t *dicp;
2201 int need_free = 0;
2202
2203 if (item->ri_buf[0].i_len == sizeof(xfs_inode_log_format_t)) {
2204 in_f = item->ri_buf[0].i_addr;
2205 } else {
2206 in_f = kmem_alloc(sizeof(xfs_inode_log_format_t), KM_SLEEP);
2207 need_free = 1;
2208 error = xfs_inode_item_format_convert(&item->ri_buf[0], in_f);
2209 if (error)
2210 goto error;
2211 }
2212
2213 /*
2214 * Inode buffers can be freed, look out for it,
2215 * and do not replay the inode.
2216 */
2217 if (xlog_check_buffer_cancelled(log, in_f->ilf_blkno,
2218 in_f->ilf_len, 0)) {
2219 error = 0;
2220 trace_xfs_log_recover_inode_cancel(log, in_f);
2221 goto error;
2222 }
2223 trace_xfs_log_recover_inode_recover(log, in_f);
2224
2225 bp = xfs_buf_read(mp->m_ddev_targp, in_f->ilf_blkno, in_f->ilf_len,
2226 XBF_LOCK);
2227 if (!bp) {
2228 error = ENOMEM;
2229 goto error;
2230 }
2231 error = bp->b_error;
2232 if (error) {
2233 xfs_ioerror_alert("xlog_recover_do..(read#2)", mp,
2234 bp, in_f->ilf_blkno);
2235 xfs_buf_relse(bp);
2236 goto error;
2237 }
2238 ASSERT(in_f->ilf_fields & XFS_ILOG_CORE);
2239 dip = (xfs_dinode_t *)xfs_buf_offset(bp, in_f->ilf_boffset);
2240
2241 /*
2242 * Make sure the place we're flushing out to really looks
2243 * like an inode!
2244 */
2245 if (unlikely(dip->di_magic != cpu_to_be16(XFS_DINODE_MAGIC))) {
2246 xfs_buf_relse(bp);
2247 xfs_alert(mp,
2248 "%s: Bad inode magic number, dip = 0x%p, dino bp = 0x%p, ino = %Ld",
2249 __func__, dip, bp, in_f->ilf_ino);
2250 XFS_ERROR_REPORT("xlog_recover_inode_pass2(1)",
2251 XFS_ERRLEVEL_LOW, mp);
2252 error = EFSCORRUPTED;
2253 goto error;
2254 }
2255 dicp = item->ri_buf[1].i_addr;
2256 if (unlikely(dicp->di_magic != XFS_DINODE_MAGIC)) {
2257 xfs_buf_relse(bp);
2258 xfs_alert(mp,
2259 "%s: Bad inode log record, rec ptr 0x%p, ino %Ld",
2260 __func__, item, in_f->ilf_ino);
2261 XFS_ERROR_REPORT("xlog_recover_inode_pass2(2)",
2262 XFS_ERRLEVEL_LOW, mp);
2263 error = EFSCORRUPTED;
2264 goto error;
2265 }
2266
2267 /* Skip replay when the on disk inode is newer than the log one */
2268 if (dicp->di_flushiter < be16_to_cpu(dip->di_flushiter)) {
2269 /*
2270 * Deal with the wrap case, DI_MAX_FLUSH is less
2271 * than smaller numbers
2272 */
2273 if (be16_to_cpu(dip->di_flushiter) == DI_MAX_FLUSH &&
2274 dicp->di_flushiter < (DI_MAX_FLUSH >> 1)) {
2275 /* do nothing */
2276 } else {
2277 xfs_buf_relse(bp);
2278 trace_xfs_log_recover_inode_skip(log, in_f);
2279 error = 0;
2280 goto error;
2281 }
2282 }
2283 /* Take the opportunity to reset the flush iteration count */
2284 dicp->di_flushiter = 0;
2285
2286 if (unlikely(S_ISREG(dicp->di_mode))) {
2287 if ((dicp->di_format != XFS_DINODE_FMT_EXTENTS) &&
2288 (dicp->di_format != XFS_DINODE_FMT_BTREE)) {
2289 XFS_CORRUPTION_ERROR("xlog_recover_inode_pass2(3)",
2290 XFS_ERRLEVEL_LOW, mp, dicp);
2291 xfs_buf_relse(bp);
2292 xfs_alert(mp,
2293 "%s: Bad regular inode log record, rec ptr 0x%p, "
2294 "ino ptr = 0x%p, ino bp = 0x%p, ino %Ld",
2295 __func__, item, dip, bp, in_f->ilf_ino);
2296 error = EFSCORRUPTED;
2297 goto error;
2298 }
2299 } else if (unlikely(S_ISDIR(dicp->di_mode))) {
2300 if ((dicp->di_format != XFS_DINODE_FMT_EXTENTS) &&
2301 (dicp->di_format != XFS_DINODE_FMT_BTREE) &&
2302 (dicp->di_format != XFS_DINODE_FMT_LOCAL)) {
2303 XFS_CORRUPTION_ERROR("xlog_recover_inode_pass2(4)",
2304 XFS_ERRLEVEL_LOW, mp, dicp);
2305 xfs_buf_relse(bp);
2306 xfs_alert(mp,
2307 "%s: Bad dir inode log record, rec ptr 0x%p, "
2308 "ino ptr = 0x%p, ino bp = 0x%p, ino %Ld",
2309 __func__, item, dip, bp, in_f->ilf_ino);
2310 error = EFSCORRUPTED;
2311 goto error;
2312 }
2313 }
2314 if (unlikely(dicp->di_nextents + dicp->di_anextents > dicp->di_nblocks)){
2315 XFS_CORRUPTION_ERROR("xlog_recover_inode_pass2(5)",
2316 XFS_ERRLEVEL_LOW, mp, dicp);
2317 xfs_buf_relse(bp);
2318 xfs_alert(mp,
2319 "%s: Bad inode log record, rec ptr 0x%p, dino ptr 0x%p, "
2320 "dino bp 0x%p, ino %Ld, total extents = %d, nblocks = %Ld",
2321 __func__, item, dip, bp, in_f->ilf_ino,
2322 dicp->di_nextents + dicp->di_anextents,
2323 dicp->di_nblocks);
2324 error = EFSCORRUPTED;
2325 goto error;
2326 }
2327 if (unlikely(dicp->di_forkoff > mp->m_sb.sb_inodesize)) {
2328 XFS_CORRUPTION_ERROR("xlog_recover_inode_pass2(6)",
2329 XFS_ERRLEVEL_LOW, mp, dicp);
2330 xfs_buf_relse(bp);
2331 xfs_alert(mp,
2332 "%s: Bad inode log record, rec ptr 0x%p, dino ptr 0x%p, "
2333 "dino bp 0x%p, ino %Ld, forkoff 0x%x", __func__,
2334 item, dip, bp, in_f->ilf_ino, dicp->di_forkoff);
2335 error = EFSCORRUPTED;
2336 goto error;
2337 }
2338 if (unlikely(item->ri_buf[1].i_len > sizeof(struct xfs_icdinode))) {
2339 XFS_CORRUPTION_ERROR("xlog_recover_inode_pass2(7)",
2340 XFS_ERRLEVEL_LOW, mp, dicp);
2341 xfs_buf_relse(bp);
2342 xfs_alert(mp,
2343 "%s: Bad inode log record length %d, rec ptr 0x%p",
2344 __func__, item->ri_buf[1].i_len, item);
2345 error = EFSCORRUPTED;
2346 goto error;
2347 }
2348
2349 /* The core is in in-core format */
2350 xfs_dinode_to_disk(dip, item->ri_buf[1].i_addr);
2351
2352 /* the rest is in on-disk format */
2353 if (item->ri_buf[1].i_len > sizeof(struct xfs_icdinode)) {
2354 memcpy((xfs_caddr_t) dip + sizeof(struct xfs_icdinode),
2355 item->ri_buf[1].i_addr + sizeof(struct xfs_icdinode),
2356 item->ri_buf[1].i_len - sizeof(struct xfs_icdinode));
2357 }
2358
2359 fields = in_f->ilf_fields;
2360 switch (fields & (XFS_ILOG_DEV | XFS_ILOG_UUID)) {
2361 case XFS_ILOG_DEV:
2362 xfs_dinode_put_rdev(dip, in_f->ilf_u.ilfu_rdev);
2363 break;
2364 case XFS_ILOG_UUID:
2365 memcpy(XFS_DFORK_DPTR(dip),
2366 &in_f->ilf_u.ilfu_uuid,
2367 sizeof(uuid_t));
2368 break;
2369 }
2370
2371 if (in_f->ilf_size == 2)
2372 goto write_inode_buffer;
2373 len = item->ri_buf[2].i_len;
2374 src = item->ri_buf[2].i_addr;
2375 ASSERT(in_f->ilf_size <= 4);
2376 ASSERT((in_f->ilf_size == 3) || (fields & XFS_ILOG_AFORK));
2377 ASSERT(!(fields & XFS_ILOG_DFORK) ||
2378 (len == in_f->ilf_dsize));
2379
2380 switch (fields & XFS_ILOG_DFORK) {
2381 case XFS_ILOG_DDATA:
2382 case XFS_ILOG_DEXT:
2383 memcpy(XFS_DFORK_DPTR(dip), src, len);
2384 break;
2385
2386 case XFS_ILOG_DBROOT:
2387 xfs_bmbt_to_bmdr(mp, (struct xfs_btree_block *)src, len,
2388 (xfs_bmdr_block_t *)XFS_DFORK_DPTR(dip),
2389 XFS_DFORK_DSIZE(dip, mp));
2390 break;
2391
2392 default:
2393 /*
2394 * There are no data fork flags set.
2395 */
2396 ASSERT((fields & XFS_ILOG_DFORK) == 0);
2397 break;
2398 }
2399
2400 /*
2401 * If we logged any attribute data, recover it. There may or
2402 * may not have been any other non-core data logged in this
2403 * transaction.
2404 */
2405 if (in_f->ilf_fields & XFS_ILOG_AFORK) {
2406 if (in_f->ilf_fields & XFS_ILOG_DFORK) {
2407 attr_index = 3;
2408 } else {
2409 attr_index = 2;
2410 }
2411 len = item->ri_buf[attr_index].i_len;
2412 src = item->ri_buf[attr_index].i_addr;
2413 ASSERT(len == in_f->ilf_asize);
2414
2415 switch (in_f->ilf_fields & XFS_ILOG_AFORK) {
2416 case XFS_ILOG_ADATA:
2417 case XFS_ILOG_AEXT:
2418 dest = XFS_DFORK_APTR(dip);
2419 ASSERT(len <= XFS_DFORK_ASIZE(dip, mp));
2420 memcpy(dest, src, len);
2421 break;
2422
2423 case XFS_ILOG_ABROOT:
2424 dest = XFS_DFORK_APTR(dip);
2425 xfs_bmbt_to_bmdr(mp, (struct xfs_btree_block *)src,
2426 len, (xfs_bmdr_block_t*)dest,
2427 XFS_DFORK_ASIZE(dip, mp));
2428 break;
2429
2430 default:
2431 xfs_warn(log->l_mp, "%s: Invalid flag", __func__);
2432 ASSERT(0);
2433 xfs_buf_relse(bp);
2434 error = EIO;
2435 goto error;
2436 }
2437 }
2438
2439write_inode_buffer:
2440 ASSERT(bp->b_target->bt_mount == mp);
2441 bp->b_iodone = xlog_recover_iodone;
2442 xfs_bdwrite(mp, bp);
2443error:
2444 if (need_free)
2445 kmem_free(in_f);
2446 return XFS_ERROR(error);
2447}
2448
2449/*
2450 * Recover QUOTAOFF records. We simply make a note of it in the xlog_t
2451 * structure, so that we know not to do any dquot item or dquot buffer recovery,
2452 * of that type.
2453 */
2454STATIC int
2455xlog_recover_quotaoff_pass1(
2456 xlog_t *log,
2457 xlog_recover_item_t *item)
2458{
2459 xfs_qoff_logformat_t *qoff_f = item->ri_buf[0].i_addr;
2460 ASSERT(qoff_f);
2461
2462 /*
2463 * The logitem format's flag tells us if this was user quotaoff,
2464 * group/project quotaoff or both.
2465 */
2466 if (qoff_f->qf_flags & XFS_UQUOTA_ACCT)
2467 log->l_quotaoffs_flag |= XFS_DQ_USER;
2468 if (qoff_f->qf_flags & XFS_PQUOTA_ACCT)
2469 log->l_quotaoffs_flag |= XFS_DQ_PROJ;
2470 if (qoff_f->qf_flags & XFS_GQUOTA_ACCT)
2471 log->l_quotaoffs_flag |= XFS_DQ_GROUP;
2472
2473 return (0);
2474}
2475
2476/*
2477 * Recover a dquot record
2478 */
2479STATIC int
2480xlog_recover_dquot_pass2(
2481 xlog_t *log,
2482 xlog_recover_item_t *item)
2483{
2484 xfs_mount_t *mp = log->l_mp;
2485 xfs_buf_t *bp;
2486 struct xfs_disk_dquot *ddq, *recddq;
2487 int error;
2488 xfs_dq_logformat_t *dq_f;
2489 uint type;
2490
2491
2492 /*
2493 * Filesystems are required to send in quota flags at mount time.
2494 */
2495 if (mp->m_qflags == 0)
2496 return (0);
2497
2498 recddq = item->ri_buf[1].i_addr;
2499 if (recddq == NULL) {
2500 xfs_alert(log->l_mp, "NULL dquot in %s.", __func__);
2501 return XFS_ERROR(EIO);
2502 }
2503 if (item->ri_buf[1].i_len < sizeof(xfs_disk_dquot_t)) {
2504 xfs_alert(log->l_mp, "dquot too small (%d) in %s.",
2505 item->ri_buf[1].i_len, __func__);
2506 return XFS_ERROR(EIO);
2507 }
2508
2509 /*
2510 * This type of quotas was turned off, so ignore this record.
2511 */
2512 type = recddq->d_flags & (XFS_DQ_USER | XFS_DQ_PROJ | XFS_DQ_GROUP);
2513 ASSERT(type);
2514 if (log->l_quotaoffs_flag & type)
2515 return (0);
2516
2517 /*
2518 * At this point we know that quota was _not_ turned off.
2519 * Since the mount flags are not indicating to us otherwise, this
2520 * must mean that quota is on, and the dquot needs to be replayed.
2521 * Remember that we may not have fully recovered the superblock yet,
2522 * so we can't do the usual trick of looking at the SB quota bits.
2523 *
2524 * The other possibility, of course, is that the quota subsystem was
2525 * removed since the last mount - ENOSYS.
2526 */
2527 dq_f = item->ri_buf[0].i_addr;
2528 ASSERT(dq_f);
2529 error = xfs_qm_dqcheck(mp, recddq, dq_f->qlf_id, 0, XFS_QMOPT_DOWARN,
2530 "xlog_recover_dquot_pass2 (log copy)");
2531 if (error)
2532 return XFS_ERROR(EIO);
2533 ASSERT(dq_f->qlf_len == 1);
2534
2535 error = xfs_read_buf(mp, mp->m_ddev_targp,
2536 dq_f->qlf_blkno,
2537 XFS_FSB_TO_BB(mp, dq_f->qlf_len),
2538 0, &bp);
2539 if (error) {
2540 xfs_ioerror_alert("xlog_recover_do..(read#3)", mp,
2541 bp, dq_f->qlf_blkno);
2542 return error;
2543 }
2544 ASSERT(bp);
2545 ddq = (xfs_disk_dquot_t *)xfs_buf_offset(bp, dq_f->qlf_boffset);
2546
2547 /*
2548 * At least the magic num portion should be on disk because this
2549 * was among a chunk of dquots created earlier, and we did some
2550 * minimal initialization then.
2551 */
2552 error = xfs_qm_dqcheck(mp, ddq, dq_f->qlf_id, 0, XFS_QMOPT_DOWARN,
2553 "xlog_recover_dquot_pass2");
2554 if (error) {
2555 xfs_buf_relse(bp);
2556 return XFS_ERROR(EIO);
2557 }
2558
2559 memcpy(ddq, recddq, item->ri_buf[1].i_len);
2560
2561 ASSERT(dq_f->qlf_size == 2);
2562 ASSERT(bp->b_target->bt_mount == mp);
2563 bp->b_iodone = xlog_recover_iodone;
2564 xfs_bdwrite(mp, bp);
2565
2566 return (0);
2567}
2568
2569/*
2570 * This routine is called to create an in-core extent free intent
2571 * item from the efi format structure which was logged on disk.
2572 * It allocates an in-core efi, copies the extents from the format
2573 * structure into it, and adds the efi to the AIL with the given
2574 * LSN.
2575 */
2576STATIC int
2577xlog_recover_efi_pass2(
2578 xlog_t *log,
2579 xlog_recover_item_t *item,
2580 xfs_lsn_t lsn)
2581{
2582 int error;
2583 xfs_mount_t *mp = log->l_mp;
2584 xfs_efi_log_item_t *efip;
2585 xfs_efi_log_format_t *efi_formatp;
2586
2587 efi_formatp = item->ri_buf[0].i_addr;
2588
2589 efip = xfs_efi_init(mp, efi_formatp->efi_nextents);
2590 if ((error = xfs_efi_copy_format(&(item->ri_buf[0]),
2591 &(efip->efi_format)))) {
2592 xfs_efi_item_free(efip);
2593 return error;
2594 }
2595 atomic_set(&efip->efi_next_extent, efi_formatp->efi_nextents);
2596
2597 spin_lock(&log->l_ailp->xa_lock);
2598 /*
2599 * xfs_trans_ail_update() drops the AIL lock.
2600 */
2601 xfs_trans_ail_update(log->l_ailp, &efip->efi_item, lsn);
2602 return 0;
2603}
2604
2605
2606/*
2607 * This routine is called when an efd format structure is found in
2608 * a committed transaction in the log. It's purpose is to cancel
2609 * the corresponding efi if it was still in the log. To do this
2610 * it searches the AIL for the efi with an id equal to that in the
2611 * efd format structure. If we find it, we remove the efi from the
2612 * AIL and free it.
2613 */
2614STATIC int
2615xlog_recover_efd_pass2(
2616 xlog_t *log,
2617 xlog_recover_item_t *item)
2618{
2619 xfs_efd_log_format_t *efd_formatp;
2620 xfs_efi_log_item_t *efip = NULL;
2621 xfs_log_item_t *lip;
2622 __uint64_t efi_id;
2623 struct xfs_ail_cursor cur;
2624 struct xfs_ail *ailp = log->l_ailp;
2625
2626 efd_formatp = item->ri_buf[0].i_addr;
2627 ASSERT((item->ri_buf[0].i_len == (sizeof(xfs_efd_log_format_32_t) +
2628 ((efd_formatp->efd_nextents - 1) * sizeof(xfs_extent_32_t)))) ||
2629 (item->ri_buf[0].i_len == (sizeof(xfs_efd_log_format_64_t) +
2630 ((efd_formatp->efd_nextents - 1) * sizeof(xfs_extent_64_t)))));
2631 efi_id = efd_formatp->efd_efi_id;
2632
2633 /*
2634 * Search for the efi with the id in the efd format structure
2635 * in the AIL.
2636 */
2637 spin_lock(&ailp->xa_lock);
2638 lip = xfs_trans_ail_cursor_first(ailp, &cur, 0);
2639 while (lip != NULL) {
2640 if (lip->li_type == XFS_LI_EFI) {
2641 efip = (xfs_efi_log_item_t *)lip;
2642 if (efip->efi_format.efi_id == efi_id) {
2643 /*
2644 * xfs_trans_ail_delete() drops the
2645 * AIL lock.
2646 */
2647 xfs_trans_ail_delete(ailp, lip);
2648 xfs_efi_item_free(efip);
2649 spin_lock(&ailp->xa_lock);
2650 break;
2651 }
2652 }
2653 lip = xfs_trans_ail_cursor_next(ailp, &cur);
2654 }
2655 xfs_trans_ail_cursor_done(ailp, &cur);
2656 spin_unlock(&ailp->xa_lock);
2657
2658 return 0;
2659}
2660
2661/*
2662 * Free up any resources allocated by the transaction
2663 *
2664 * Remember that EFIs, EFDs, and IUNLINKs are handled later.
2665 */
2666STATIC void
2667xlog_recover_free_trans(
2668 struct xlog_recover *trans)
2669{
2670 xlog_recover_item_t *item, *n;
2671 int i;
2672
2673 list_for_each_entry_safe(item, n, &trans->r_itemq, ri_list) {
2674 /* Free the regions in the item. */
2675 list_del(&item->ri_list);
2676 for (i = 0; i < item->ri_cnt; i++)
2677 kmem_free(item->ri_buf[i].i_addr);
2678 /* Free the item itself */
2679 kmem_free(item->ri_buf);
2680 kmem_free(item);
2681 }
2682 /* Free the transaction recover structure */
2683 kmem_free(trans);
2684}
2685
2686STATIC int
2687xlog_recover_commit_pass1(
2688 struct log *log,
2689 struct xlog_recover *trans,
2690 xlog_recover_item_t *item)
2691{
2692 trace_xfs_log_recover_item_recover(log, trans, item, XLOG_RECOVER_PASS1);
2693
2694 switch (ITEM_TYPE(item)) {
2695 case XFS_LI_BUF:
2696 return xlog_recover_buffer_pass1(log, item);
2697 case XFS_LI_QUOTAOFF:
2698 return xlog_recover_quotaoff_pass1(log, item);
2699 case XFS_LI_INODE:
2700 case XFS_LI_EFI:
2701 case XFS_LI_EFD:
2702 case XFS_LI_DQUOT:
2703 /* nothing to do in pass 1 */
2704 return 0;
2705 default:
2706 xfs_warn(log->l_mp, "%s: invalid item type (%d)",
2707 __func__, ITEM_TYPE(item));
2708 ASSERT(0);
2709 return XFS_ERROR(EIO);
2710 }
2711}
2712
2713STATIC int
2714xlog_recover_commit_pass2(
2715 struct log *log,
2716 struct xlog_recover *trans,
2717 xlog_recover_item_t *item)
2718{
2719 trace_xfs_log_recover_item_recover(log, trans, item, XLOG_RECOVER_PASS2);
2720
2721 switch (ITEM_TYPE(item)) {
2722 case XFS_LI_BUF:
2723 return xlog_recover_buffer_pass2(log, item);
2724 case XFS_LI_INODE:
2725 return xlog_recover_inode_pass2(log, item);
2726 case XFS_LI_EFI:
2727 return xlog_recover_efi_pass2(log, item, trans->r_lsn);
2728 case XFS_LI_EFD:
2729 return xlog_recover_efd_pass2(log, item);
2730 case XFS_LI_DQUOT:
2731 return xlog_recover_dquot_pass2(log, item);
2732 case XFS_LI_QUOTAOFF:
2733 /* nothing to do in pass2 */
2734 return 0;
2735 default:
2736 xfs_warn(log->l_mp, "%s: invalid item type (%d)",
2737 __func__, ITEM_TYPE(item));
2738 ASSERT(0);
2739 return XFS_ERROR(EIO);
2740 }
2741}
2742
2743/*
2744 * Perform the transaction.
2745 *
2746 * If the transaction modifies a buffer or inode, do it now. Otherwise,
2747 * EFIs and EFDs get queued up by adding entries into the AIL for them.
2748 */
2749STATIC int
2750xlog_recover_commit_trans(
2751 struct log *log,
2752 struct xlog_recover *trans,
2753 int pass)
2754{
2755 int error = 0;
2756 xlog_recover_item_t *item;
2757
2758 hlist_del(&trans->r_list);
2759
2760 error = xlog_recover_reorder_trans(log, trans, pass);
2761 if (error)
2762 return error;
2763
2764 list_for_each_entry(item, &trans->r_itemq, ri_list) {
2765 if (pass == XLOG_RECOVER_PASS1)
2766 error = xlog_recover_commit_pass1(log, trans, item);
2767 else
2768 error = xlog_recover_commit_pass2(log, trans, item);
2769 if (error)
2770 return error;
2771 }
2772
2773 xlog_recover_free_trans(trans);
2774 return 0;
2775}
2776
2777STATIC int
2778xlog_recover_unmount_trans(
2779 struct log *log,
2780 xlog_recover_t *trans)
2781{
2782 /* Do nothing now */
2783 xfs_warn(log->l_mp, "%s: Unmount LR", __func__);
2784 return 0;
2785}
2786
2787/*
2788 * There are two valid states of the r_state field. 0 indicates that the
2789 * transaction structure is in a normal state. We have either seen the
2790 * start of the transaction or the last operation we added was not a partial
2791 * operation. If the last operation we added to the transaction was a
2792 * partial operation, we need to mark r_state with XLOG_WAS_CONT_TRANS.
2793 *
2794 * NOTE: skip LRs with 0 data length.
2795 */
2796STATIC int
2797xlog_recover_process_data(
2798 xlog_t *log,
2799 struct hlist_head rhash[],
2800 xlog_rec_header_t *rhead,
2801 xfs_caddr_t dp,
2802 int pass)
2803{
2804 xfs_caddr_t lp;
2805 int num_logops;
2806 xlog_op_header_t *ohead;
2807 xlog_recover_t *trans;
2808 xlog_tid_t tid;
2809 int error;
2810 unsigned long hash;
2811 uint flags;
2812
2813 lp = dp + be32_to_cpu(rhead->h_len);
2814 num_logops = be32_to_cpu(rhead->h_num_logops);
2815
2816 /* check the log format matches our own - else we can't recover */
2817 if (xlog_header_check_recover(log->l_mp, rhead))
2818 return (XFS_ERROR(EIO));
2819
2820 while ((dp < lp) && num_logops) {
2821 ASSERT(dp + sizeof(xlog_op_header_t) <= lp);
2822 ohead = (xlog_op_header_t *)dp;
2823 dp += sizeof(xlog_op_header_t);
2824 if (ohead->oh_clientid != XFS_TRANSACTION &&
2825 ohead->oh_clientid != XFS_LOG) {
2826 xfs_warn(log->l_mp, "%s: bad clientid 0x%x",
2827 __func__, ohead->oh_clientid);
2828 ASSERT(0);
2829 return (XFS_ERROR(EIO));
2830 }
2831 tid = be32_to_cpu(ohead->oh_tid);
2832 hash = XLOG_RHASH(tid);
2833 trans = xlog_recover_find_tid(&rhash[hash], tid);
2834 if (trans == NULL) { /* not found; add new tid */
2835 if (ohead->oh_flags & XLOG_START_TRANS)
2836 xlog_recover_new_tid(&rhash[hash], tid,
2837 be64_to_cpu(rhead->h_lsn));
2838 } else {
2839 if (dp + be32_to_cpu(ohead->oh_len) > lp) {
2840 xfs_warn(log->l_mp, "%s: bad length 0x%x",
2841 __func__, be32_to_cpu(ohead->oh_len));
2842 WARN_ON(1);
2843 return (XFS_ERROR(EIO));
2844 }
2845 flags = ohead->oh_flags & ~XLOG_END_TRANS;
2846 if (flags & XLOG_WAS_CONT_TRANS)
2847 flags &= ~XLOG_CONTINUE_TRANS;
2848 switch (flags) {
2849 case XLOG_COMMIT_TRANS:
2850 error = xlog_recover_commit_trans(log,
2851 trans, pass);
2852 break;
2853 case XLOG_UNMOUNT_TRANS:
2854 error = xlog_recover_unmount_trans(log, trans);
2855 break;
2856 case XLOG_WAS_CONT_TRANS:
2857 error = xlog_recover_add_to_cont_trans(log,
2858 trans, dp,
2859 be32_to_cpu(ohead->oh_len));
2860 break;
2861 case XLOG_START_TRANS:
2862 xfs_warn(log->l_mp, "%s: bad transaction",
2863 __func__);
2864 ASSERT(0);
2865 error = XFS_ERROR(EIO);
2866 break;
2867 case 0:
2868 case XLOG_CONTINUE_TRANS:
2869 error = xlog_recover_add_to_trans(log, trans,
2870 dp, be32_to_cpu(ohead->oh_len));
2871 break;
2872 default:
2873 xfs_warn(log->l_mp, "%s: bad flag 0x%x",
2874 __func__, flags);
2875 ASSERT(0);
2876 error = XFS_ERROR(EIO);
2877 break;
2878 }
2879 if (error)
2880 return error;
2881 }
2882 dp += be32_to_cpu(ohead->oh_len);
2883 num_logops--;
2884 }
2885 return 0;
2886}
2887
2888/*
2889 * Process an extent free intent item that was recovered from
2890 * the log. We need to free the extents that it describes.
2891 */
2892STATIC int
2893xlog_recover_process_efi(
2894 xfs_mount_t *mp,
2895 xfs_efi_log_item_t *efip)
2896{
2897 xfs_efd_log_item_t *efdp;
2898 xfs_trans_t *tp;
2899 int i;
2900 int error = 0;
2901 xfs_extent_t *extp;
2902 xfs_fsblock_t startblock_fsb;
2903
2904 ASSERT(!test_bit(XFS_EFI_RECOVERED, &efip->efi_flags));
2905
2906 /*
2907 * First check the validity of the extents described by the
2908 * EFI. If any are bad, then assume that all are bad and
2909 * just toss the EFI.
2910 */
2911 for (i = 0; i < efip->efi_format.efi_nextents; i++) {
2912 extp = &(efip->efi_format.efi_extents[i]);
2913 startblock_fsb = XFS_BB_TO_FSB(mp,
2914 XFS_FSB_TO_DADDR(mp, extp->ext_start));
2915 if ((startblock_fsb == 0) ||
2916 (extp->ext_len == 0) ||
2917 (startblock_fsb >= mp->m_sb.sb_dblocks) ||
2918 (extp->ext_len >= mp->m_sb.sb_agblocks)) {
2919 /*
2920 * This will pull the EFI from the AIL and
2921 * free the memory associated with it.
2922 */
2923 xfs_efi_release(efip, efip->efi_format.efi_nextents);
2924 return XFS_ERROR(EIO);
2925 }
2926 }
2927
2928 tp = xfs_trans_alloc(mp, 0);
2929 error = xfs_trans_reserve(tp, 0, XFS_ITRUNCATE_LOG_RES(mp), 0, 0, 0);
2930 if (error)
2931 goto abort_error;
2932 efdp = xfs_trans_get_efd(tp, efip, efip->efi_format.efi_nextents);
2933
2934 for (i = 0; i < efip->efi_format.efi_nextents; i++) {
2935 extp = &(efip->efi_format.efi_extents[i]);
2936 error = xfs_free_extent(tp, extp->ext_start, extp->ext_len);
2937 if (error)
2938 goto abort_error;
2939 xfs_trans_log_efd_extent(tp, efdp, extp->ext_start,
2940 extp->ext_len);
2941 }
2942
2943 set_bit(XFS_EFI_RECOVERED, &efip->efi_flags);
2944 error = xfs_trans_commit(tp, 0);
2945 return error;
2946
2947abort_error:
2948 xfs_trans_cancel(tp, XFS_TRANS_ABORT);
2949 return error;
2950}
2951
2952/*
2953 * When this is called, all of the EFIs which did not have
2954 * corresponding EFDs should be in the AIL. What we do now
2955 * is free the extents associated with each one.
2956 *
2957 * Since we process the EFIs in normal transactions, they
2958 * will be removed at some point after the commit. This prevents
2959 * us from just walking down the list processing each one.
2960 * We'll use a flag in the EFI to skip those that we've already
2961 * processed and use the AIL iteration mechanism's generation
2962 * count to try to speed this up at least a bit.
2963 *
2964 * When we start, we know that the EFIs are the only things in
2965 * the AIL. As we process them, however, other items are added
2966 * to the AIL. Since everything added to the AIL must come after
2967 * everything already in the AIL, we stop processing as soon as
2968 * we see something other than an EFI in the AIL.
2969 */
2970STATIC int
2971xlog_recover_process_efis(
2972 xlog_t *log)
2973{
2974 xfs_log_item_t *lip;
2975 xfs_efi_log_item_t *efip;
2976 int error = 0;
2977 struct xfs_ail_cursor cur;
2978 struct xfs_ail *ailp;
2979
2980 ailp = log->l_ailp;
2981 spin_lock(&ailp->xa_lock);
2982 lip = xfs_trans_ail_cursor_first(ailp, &cur, 0);
2983 while (lip != NULL) {
2984 /*
2985 * We're done when we see something other than an EFI.
2986 * There should be no EFIs left in the AIL now.
2987 */
2988 if (lip->li_type != XFS_LI_EFI) {
2989#ifdef DEBUG
2990 for (; lip; lip = xfs_trans_ail_cursor_next(ailp, &cur))
2991 ASSERT(lip->li_type != XFS_LI_EFI);
2992#endif
2993 break;
2994 }
2995
2996 /*
2997 * Skip EFIs that we've already processed.
2998 */
2999 efip = (xfs_efi_log_item_t *)lip;
3000 if (test_bit(XFS_EFI_RECOVERED, &efip->efi_flags)) {
3001 lip = xfs_trans_ail_cursor_next(ailp, &cur);
3002 continue;
3003 }
3004
3005 spin_unlock(&ailp->xa_lock);
3006 error = xlog_recover_process_efi(log->l_mp, efip);
3007 spin_lock(&ailp->xa_lock);
3008 if (error)
3009 goto out;
3010 lip = xfs_trans_ail_cursor_next(ailp, &cur);
3011 }
3012out:
3013 xfs_trans_ail_cursor_done(ailp, &cur);
3014 spin_unlock(&ailp->xa_lock);
3015 return error;
3016}
3017
3018/*
3019 * This routine performs a transaction to null out a bad inode pointer
3020 * in an agi unlinked inode hash bucket.
3021 */
3022STATIC void
3023xlog_recover_clear_agi_bucket(
3024 xfs_mount_t *mp,
3025 xfs_agnumber_t agno,
3026 int bucket)
3027{
3028 xfs_trans_t *tp;
3029 xfs_agi_t *agi;
3030 xfs_buf_t *agibp;
3031 int offset;
3032 int error;
3033
3034 tp = xfs_trans_alloc(mp, XFS_TRANS_CLEAR_AGI_BUCKET);
3035 error = xfs_trans_reserve(tp, 0, XFS_CLEAR_AGI_BUCKET_LOG_RES(mp),
3036 0, 0, 0);
3037 if (error)
3038 goto out_abort;
3039
3040 error = xfs_read_agi(mp, tp, agno, &agibp);
3041 if (error)
3042 goto out_abort;
3043
3044 agi = XFS_BUF_TO_AGI(agibp);
3045 agi->agi_unlinked[bucket] = cpu_to_be32(NULLAGINO);
3046 offset = offsetof(xfs_agi_t, agi_unlinked) +
3047 (sizeof(xfs_agino_t) * bucket);
3048 xfs_trans_log_buf(tp, agibp, offset,
3049 (offset + sizeof(xfs_agino_t) - 1));
3050
3051 error = xfs_trans_commit(tp, 0);
3052 if (error)
3053 goto out_error;
3054 return;
3055
3056out_abort:
3057 xfs_trans_cancel(tp, XFS_TRANS_ABORT);
3058out_error:
3059 xfs_warn(mp, "%s: failed to clear agi %d. Continuing.", __func__, agno);
3060 return;
3061}
3062
3063STATIC xfs_agino_t
3064xlog_recover_process_one_iunlink(
3065 struct xfs_mount *mp,
3066 xfs_agnumber_t agno,
3067 xfs_agino_t agino,
3068 int bucket)
3069{
3070 struct xfs_buf *ibp;
3071 struct xfs_dinode *dip;
3072 struct xfs_inode *ip;
3073 xfs_ino_t ino;
3074 int error;
3075
3076 ino = XFS_AGINO_TO_INO(mp, agno, agino);
3077 error = xfs_iget(mp, NULL, ino, 0, 0, &ip);
3078 if (error)
3079 goto fail;
3080
3081 /*
3082 * Get the on disk inode to find the next inode in the bucket.
3083 */
3084 error = xfs_itobp(mp, NULL, ip, &dip, &ibp, XBF_LOCK);
3085 if (error)
3086 goto fail_iput;
3087
3088 ASSERT(ip->i_d.di_nlink == 0);
3089 ASSERT(ip->i_d.di_mode != 0);
3090
3091 /* setup for the next pass */
3092 agino = be32_to_cpu(dip->di_next_unlinked);
3093 xfs_buf_relse(ibp);
3094
3095 /*
3096 * Prevent any DMAPI event from being sent when the reference on
3097 * the inode is dropped.
3098 */
3099 ip->i_d.di_dmevmask = 0;
3100
3101 IRELE(ip);
3102 return agino;
3103
3104 fail_iput:
3105 IRELE(ip);
3106 fail:
3107 /*
3108 * We can't read in the inode this bucket points to, or this inode
3109 * is messed up. Just ditch this bucket of inodes. We will lose
3110 * some inodes and space, but at least we won't hang.
3111 *
3112 * Call xlog_recover_clear_agi_bucket() to perform a transaction to
3113 * clear the inode pointer in the bucket.
3114 */
3115 xlog_recover_clear_agi_bucket(mp, agno, bucket);
3116 return NULLAGINO;
3117}
3118
3119/*
3120 * xlog_iunlink_recover
3121 *
3122 * This is called during recovery to process any inodes which
3123 * we unlinked but not freed when the system crashed. These
3124 * inodes will be on the lists in the AGI blocks. What we do
3125 * here is scan all the AGIs and fully truncate and free any
3126 * inodes found on the lists. Each inode is removed from the
3127 * lists when it has been fully truncated and is freed. The
3128 * freeing of the inode and its removal from the list must be
3129 * atomic.
3130 */
3131STATIC void
3132xlog_recover_process_iunlinks(
3133 xlog_t *log)
3134{
3135 xfs_mount_t *mp;
3136 xfs_agnumber_t agno;
3137 xfs_agi_t *agi;
3138 xfs_buf_t *agibp;
3139 xfs_agino_t agino;
3140 int bucket;
3141 int error;
3142 uint mp_dmevmask;
3143
3144 mp = log->l_mp;
3145
3146 /*
3147 * Prevent any DMAPI event from being sent while in this function.
3148 */
3149 mp_dmevmask = mp->m_dmevmask;
3150 mp->m_dmevmask = 0;
3151
3152 for (agno = 0; agno < mp->m_sb.sb_agcount; agno++) {
3153 /*
3154 * Find the agi for this ag.
3155 */
3156 error = xfs_read_agi(mp, NULL, agno, &agibp);
3157 if (error) {
3158 /*
3159 * AGI is b0rked. Don't process it.
3160 *
3161 * We should probably mark the filesystem as corrupt
3162 * after we've recovered all the ag's we can....
3163 */
3164 continue;
3165 }
3166 agi = XFS_BUF_TO_AGI(agibp);
3167
3168 for (bucket = 0; bucket < XFS_AGI_UNLINKED_BUCKETS; bucket++) {
3169 agino = be32_to_cpu(agi->agi_unlinked[bucket]);
3170 while (agino != NULLAGINO) {
3171 /*
3172 * Release the agi buffer so that it can
3173 * be acquired in the normal course of the
3174 * transaction to truncate and free the inode.
3175 */
3176 xfs_buf_relse(agibp);
3177
3178 agino = xlog_recover_process_one_iunlink(mp,
3179 agno, agino, bucket);
3180
3181 /*
3182 * Reacquire the agibuffer and continue around
3183 * the loop. This should never fail as we know
3184 * the buffer was good earlier on.
3185 */
3186 error = xfs_read_agi(mp, NULL, agno, &agibp);
3187 ASSERT(error == 0);
3188 agi = XFS_BUF_TO_AGI(agibp);
3189 }
3190 }
3191
3192 /*
3193 * Release the buffer for the current agi so we can
3194 * go on to the next one.
3195 */
3196 xfs_buf_relse(agibp);
3197 }
3198
3199 mp->m_dmevmask = mp_dmevmask;
3200}
3201
3202
3203#ifdef DEBUG
3204STATIC void
3205xlog_pack_data_checksum(
3206 xlog_t *log,
3207 xlog_in_core_t *iclog,
3208 int size)
3209{
3210 int i;
3211 __be32 *up;
3212 uint chksum = 0;
3213
3214 up = (__be32 *)iclog->ic_datap;
3215 /* divide length by 4 to get # words */
3216 for (i = 0; i < (size >> 2); i++) {
3217 chksum ^= be32_to_cpu(*up);
3218 up++;
3219 }
3220 iclog->ic_header.h_chksum = cpu_to_be32(chksum);
3221}
3222#else
3223#define xlog_pack_data_checksum(log, iclog, size)
3224#endif
3225
3226/*
3227 * Stamp cycle number in every block
3228 */
3229void
3230xlog_pack_data(
3231 xlog_t *log,
3232 xlog_in_core_t *iclog,
3233 int roundoff)
3234{
3235 int i, j, k;
3236 int size = iclog->ic_offset + roundoff;
3237 __be32 cycle_lsn;
3238 xfs_caddr_t dp;
3239
3240 xlog_pack_data_checksum(log, iclog, size);
3241
3242 cycle_lsn = CYCLE_LSN_DISK(iclog->ic_header.h_lsn);
3243
3244 dp = iclog->ic_datap;
3245 for (i = 0; i < BTOBB(size) &&
3246 i < (XLOG_HEADER_CYCLE_SIZE / BBSIZE); i++) {
3247 iclog->ic_header.h_cycle_data[i] = *(__be32 *)dp;
3248 *(__be32 *)dp = cycle_lsn;
3249 dp += BBSIZE;
3250 }
3251
3252 if (xfs_sb_version_haslogv2(&log->l_mp->m_sb)) {
3253 xlog_in_core_2_t *xhdr = iclog->ic_data;
3254
3255 for ( ; i < BTOBB(size); i++) {
3256 j = i / (XLOG_HEADER_CYCLE_SIZE / BBSIZE);
3257 k = i % (XLOG_HEADER_CYCLE_SIZE / BBSIZE);
3258 xhdr[j].hic_xheader.xh_cycle_data[k] = *(__be32 *)dp;
3259 *(__be32 *)dp = cycle_lsn;
3260 dp += BBSIZE;
3261 }
3262
3263 for (i = 1; i < log->l_iclog_heads; i++) {
3264 xhdr[i].hic_xheader.xh_cycle = cycle_lsn;
3265 }
3266 }
3267}
3268
3269STATIC void
3270xlog_unpack_data(
3271 xlog_rec_header_t *rhead,
3272 xfs_caddr_t dp,
3273 xlog_t *log)
3274{
3275 int i, j, k;
3276
3277 for (i = 0; i < BTOBB(be32_to_cpu(rhead->h_len)) &&
3278 i < (XLOG_HEADER_CYCLE_SIZE / BBSIZE); i++) {
3279 *(__be32 *)dp = *(__be32 *)&rhead->h_cycle_data[i];
3280 dp += BBSIZE;
3281 }
3282
3283 if (xfs_sb_version_haslogv2(&log->l_mp->m_sb)) {
3284 xlog_in_core_2_t *xhdr = (xlog_in_core_2_t *)rhead;
3285 for ( ; i < BTOBB(be32_to_cpu(rhead->h_len)); i++) {
3286 j = i / (XLOG_HEADER_CYCLE_SIZE / BBSIZE);
3287 k = i % (XLOG_HEADER_CYCLE_SIZE / BBSIZE);
3288 *(__be32 *)dp = xhdr[j].hic_xheader.xh_cycle_data[k];
3289 dp += BBSIZE;
3290 }
3291 }
3292}
3293
3294STATIC int
3295xlog_valid_rec_header(
3296 xlog_t *log,
3297 xlog_rec_header_t *rhead,
3298 xfs_daddr_t blkno)
3299{
3300 int hlen;
3301
3302 if (unlikely(rhead->h_magicno != cpu_to_be32(XLOG_HEADER_MAGIC_NUM))) {
3303 XFS_ERROR_REPORT("xlog_valid_rec_header(1)",
3304 XFS_ERRLEVEL_LOW, log->l_mp);
3305 return XFS_ERROR(EFSCORRUPTED);
3306 }
3307 if (unlikely(
3308 (!rhead->h_version ||
3309 (be32_to_cpu(rhead->h_version) & (~XLOG_VERSION_OKBITS))))) {
3310 xfs_warn(log->l_mp, "%s: unrecognised log version (%d).",
3311 __func__, be32_to_cpu(rhead->h_version));
3312 return XFS_ERROR(EIO);
3313 }
3314
3315 /* LR body must have data or it wouldn't have been written */
3316 hlen = be32_to_cpu(rhead->h_len);
3317 if (unlikely( hlen <= 0 || hlen > INT_MAX )) {
3318 XFS_ERROR_REPORT("xlog_valid_rec_header(2)",
3319 XFS_ERRLEVEL_LOW, log->l_mp);
3320 return XFS_ERROR(EFSCORRUPTED);
3321 }
3322 if (unlikely( blkno > log->l_logBBsize || blkno > INT_MAX )) {
3323 XFS_ERROR_REPORT("xlog_valid_rec_header(3)",
3324 XFS_ERRLEVEL_LOW, log->l_mp);
3325 return XFS_ERROR(EFSCORRUPTED);
3326 }
3327 return 0;
3328}
3329
3330/*
3331 * Read the log from tail to head and process the log records found.
3332 * Handle the two cases where the tail and head are in the same cycle
3333 * and where the active portion of the log wraps around the end of
3334 * the physical log separately. The pass parameter is passed through
3335 * to the routines called to process the data and is not looked at
3336 * here.
3337 */
3338STATIC int
3339xlog_do_recovery_pass(
3340 xlog_t *log,
3341 xfs_daddr_t head_blk,
3342 xfs_daddr_t tail_blk,
3343 int pass)
3344{
3345 xlog_rec_header_t *rhead;
3346 xfs_daddr_t blk_no;
3347 xfs_caddr_t offset;
3348 xfs_buf_t *hbp, *dbp;
3349 int error = 0, h_size;
3350 int bblks, split_bblks;
3351 int hblks, split_hblks, wrapped_hblks;
3352 struct hlist_head rhash[XLOG_RHASH_SIZE];
3353
3354 ASSERT(head_blk != tail_blk);
3355
3356 /*
3357 * Read the header of the tail block and get the iclog buffer size from
3358 * h_size. Use this to tell how many sectors make up the log header.
3359 */
3360 if (xfs_sb_version_haslogv2(&log->l_mp->m_sb)) {
3361 /*
3362 * When using variable length iclogs, read first sector of
3363 * iclog header and extract the header size from it. Get a
3364 * new hbp that is the correct size.
3365 */
3366 hbp = xlog_get_bp(log, 1);
3367 if (!hbp)
3368 return ENOMEM;
3369
3370 error = xlog_bread(log, tail_blk, 1, hbp, &offset);
3371 if (error)
3372 goto bread_err1;
3373
3374 rhead = (xlog_rec_header_t *)offset;
3375 error = xlog_valid_rec_header(log, rhead, tail_blk);
3376 if (error)
3377 goto bread_err1;
3378 h_size = be32_to_cpu(rhead->h_size);
3379 if ((be32_to_cpu(rhead->h_version) & XLOG_VERSION_2) &&
3380 (h_size > XLOG_HEADER_CYCLE_SIZE)) {
3381 hblks = h_size / XLOG_HEADER_CYCLE_SIZE;
3382 if (h_size % XLOG_HEADER_CYCLE_SIZE)
3383 hblks++;
3384 xlog_put_bp(hbp);
3385 hbp = xlog_get_bp(log, hblks);
3386 } else {
3387 hblks = 1;
3388 }
3389 } else {
3390 ASSERT(log->l_sectBBsize == 1);
3391 hblks = 1;
3392 hbp = xlog_get_bp(log, 1);
3393 h_size = XLOG_BIG_RECORD_BSIZE;
3394 }
3395
3396 if (!hbp)
3397 return ENOMEM;
3398 dbp = xlog_get_bp(log, BTOBB(h_size));
3399 if (!dbp) {
3400 xlog_put_bp(hbp);
3401 return ENOMEM;
3402 }
3403
3404 memset(rhash, 0, sizeof(rhash));
3405 if (tail_blk <= head_blk) {
3406 for (blk_no = tail_blk; blk_no < head_blk; ) {
3407 error = xlog_bread(log, blk_no, hblks, hbp, &offset);
3408 if (error)
3409 goto bread_err2;
3410
3411 rhead = (xlog_rec_header_t *)offset;
3412 error = xlog_valid_rec_header(log, rhead, blk_no);
3413 if (error)
3414 goto bread_err2;
3415
3416 /* blocks in data section */
3417 bblks = (int)BTOBB(be32_to_cpu(rhead->h_len));
3418 error = xlog_bread(log, blk_no + hblks, bblks, dbp,
3419 &offset);
3420 if (error)
3421 goto bread_err2;
3422
3423 xlog_unpack_data(rhead, offset, log);
3424 if ((error = xlog_recover_process_data(log,
3425 rhash, rhead, offset, pass)))
3426 goto bread_err2;
3427 blk_no += bblks + hblks;
3428 }
3429 } else {
3430 /*
3431 * Perform recovery around the end of the physical log.
3432 * When the head is not on the same cycle number as the tail,
3433 * we can't do a sequential recovery as above.
3434 */
3435 blk_no = tail_blk;
3436 while (blk_no < log->l_logBBsize) {
3437 /*
3438 * Check for header wrapping around physical end-of-log
3439 */
3440 offset = hbp->b_addr;
3441 split_hblks = 0;
3442 wrapped_hblks = 0;
3443 if (blk_no + hblks <= log->l_logBBsize) {
3444 /* Read header in one read */
3445 error = xlog_bread(log, blk_no, hblks, hbp,
3446 &offset);
3447 if (error)
3448 goto bread_err2;
3449 } else {
3450 /* This LR is split across physical log end */
3451 if (blk_no != log->l_logBBsize) {
3452 /* some data before physical log end */
3453 ASSERT(blk_no <= INT_MAX);
3454 split_hblks = log->l_logBBsize - (int)blk_no;
3455 ASSERT(split_hblks > 0);
3456 error = xlog_bread(log, blk_no,
3457 split_hblks, hbp,
3458 &offset);
3459 if (error)
3460 goto bread_err2;
3461 }
3462
3463 /*
3464 * Note: this black magic still works with
3465 * large sector sizes (non-512) only because:
3466 * - we increased the buffer size originally
3467 * by 1 sector giving us enough extra space
3468 * for the second read;
3469 * - the log start is guaranteed to be sector
3470 * aligned;
3471 * - we read the log end (LR header start)
3472 * _first_, then the log start (LR header end)
3473 * - order is important.
3474 */
3475 wrapped_hblks = hblks - split_hblks;
3476 error = xlog_bread_offset(log, 0,
3477 wrapped_hblks, hbp,
3478 offset + BBTOB(split_hblks));
3479 if (error)
3480 goto bread_err2;
3481 }
3482 rhead = (xlog_rec_header_t *)offset;
3483 error = xlog_valid_rec_header(log, rhead,
3484 split_hblks ? blk_no : 0);
3485 if (error)
3486 goto bread_err2;
3487
3488 bblks = (int)BTOBB(be32_to_cpu(rhead->h_len));
3489 blk_no += hblks;
3490
3491 /* Read in data for log record */
3492 if (blk_no + bblks <= log->l_logBBsize) {
3493 error = xlog_bread(log, blk_no, bblks, dbp,
3494 &offset);
3495 if (error)
3496 goto bread_err2;
3497 } else {
3498 /* This log record is split across the
3499 * physical end of log */
3500 offset = dbp->b_addr;
3501 split_bblks = 0;
3502 if (blk_no != log->l_logBBsize) {
3503 /* some data is before the physical
3504 * end of log */
3505 ASSERT(!wrapped_hblks);
3506 ASSERT(blk_no <= INT_MAX);
3507 split_bblks =
3508 log->l_logBBsize - (int)blk_no;
3509 ASSERT(split_bblks > 0);
3510 error = xlog_bread(log, blk_no,
3511 split_bblks, dbp,
3512 &offset);
3513 if (error)
3514 goto bread_err2;
3515 }
3516
3517 /*
3518 * Note: this black magic still works with
3519 * large sector sizes (non-512) only because:
3520 * - we increased the buffer size originally
3521 * by 1 sector giving us enough extra space
3522 * for the second read;
3523 * - the log start is guaranteed to be sector
3524 * aligned;
3525 * - we read the log end (LR header start)
3526 * _first_, then the log start (LR header end)
3527 * - order is important.
3528 */
3529 error = xlog_bread_offset(log, 0,
3530 bblks - split_bblks, hbp,
3531 offset + BBTOB(split_bblks));
3532 if (error)
3533 goto bread_err2;
3534 }
3535 xlog_unpack_data(rhead, offset, log);
3536 if ((error = xlog_recover_process_data(log, rhash,
3537 rhead, offset, pass)))
3538 goto bread_err2;
3539 blk_no += bblks;
3540 }
3541
3542 ASSERT(blk_no >= log->l_logBBsize);
3543 blk_no -= log->l_logBBsize;
3544
3545 /* read first part of physical log */
3546 while (blk_no < head_blk) {
3547 error = xlog_bread(log, blk_no, hblks, hbp, &offset);
3548 if (error)
3549 goto bread_err2;
3550
3551 rhead = (xlog_rec_header_t *)offset;
3552 error = xlog_valid_rec_header(log, rhead, blk_no);
3553 if (error)
3554 goto bread_err2;
3555
3556 bblks = (int)BTOBB(be32_to_cpu(rhead->h_len));
3557 error = xlog_bread(log, blk_no+hblks, bblks, dbp,
3558 &offset);
3559 if (error)
3560 goto bread_err2;
3561
3562 xlog_unpack_data(rhead, offset, log);
3563 if ((error = xlog_recover_process_data(log, rhash,
3564 rhead, offset, pass)))
3565 goto bread_err2;
3566 blk_no += bblks + hblks;
3567 }
3568 }
3569
3570 bread_err2:
3571 xlog_put_bp(dbp);
3572 bread_err1:
3573 xlog_put_bp(hbp);
3574 return error;
3575}
3576
3577/*
3578 * Do the recovery of the log. We actually do this in two phases.
3579 * The two passes are necessary in order to implement the function
3580 * of cancelling a record written into the log. The first pass
3581 * determines those things which have been cancelled, and the
3582 * second pass replays log items normally except for those which
3583 * have been cancelled. The handling of the replay and cancellations
3584 * takes place in the log item type specific routines.
3585 *
3586 * The table of items which have cancel records in the log is allocated
3587 * and freed at this level, since only here do we know when all of
3588 * the log recovery has been completed.
3589 */
3590STATIC int
3591xlog_do_log_recovery(
3592 xlog_t *log,
3593 xfs_daddr_t head_blk,
3594 xfs_daddr_t tail_blk)
3595{
3596 int error, i;
3597
3598 ASSERT(head_blk != tail_blk);
3599
3600 /*
3601 * First do a pass to find all of the cancelled buf log items.
3602 * Store them in the buf_cancel_table for use in the second pass.
3603 */
3604 log->l_buf_cancel_table = kmem_zalloc(XLOG_BC_TABLE_SIZE *
3605 sizeof(struct list_head),
3606 KM_SLEEP);
3607 for (i = 0; i < XLOG_BC_TABLE_SIZE; i++)
3608 INIT_LIST_HEAD(&log->l_buf_cancel_table[i]);
3609
3610 error = xlog_do_recovery_pass(log, head_blk, tail_blk,
3611 XLOG_RECOVER_PASS1);
3612 if (error != 0) {
3613 kmem_free(log->l_buf_cancel_table);
3614 log->l_buf_cancel_table = NULL;
3615 return error;
3616 }
3617 /*
3618 * Then do a second pass to actually recover the items in the log.
3619 * When it is complete free the table of buf cancel items.
3620 */
3621 error = xlog_do_recovery_pass(log, head_blk, tail_blk,
3622 XLOG_RECOVER_PASS2);
3623#ifdef DEBUG
3624 if (!error) {
3625 int i;
3626
3627 for (i = 0; i < XLOG_BC_TABLE_SIZE; i++)
3628 ASSERT(list_empty(&log->l_buf_cancel_table[i]));
3629 }
3630#endif /* DEBUG */
3631
3632 kmem_free(log->l_buf_cancel_table);
3633 log->l_buf_cancel_table = NULL;
3634
3635 return error;
3636}
3637
3638/*
3639 * Do the actual recovery
3640 */
3641STATIC int
3642xlog_do_recover(
3643 xlog_t *log,
3644 xfs_daddr_t head_blk,
3645 xfs_daddr_t tail_blk)
3646{
3647 int error;
3648 xfs_buf_t *bp;
3649 xfs_sb_t *sbp;
3650
3651 /*
3652 * First replay the images in the log.
3653 */
3654 error = xlog_do_log_recovery(log, head_blk, tail_blk);
3655 if (error) {
3656 return error;
3657 }
3658
3659 XFS_bflush(log->l_mp->m_ddev_targp);
3660
3661 /*
3662 * If IO errors happened during recovery, bail out.
3663 */
3664 if (XFS_FORCED_SHUTDOWN(log->l_mp)) {
3665 return (EIO);
3666 }
3667
3668 /*
3669 * We now update the tail_lsn since much of the recovery has completed
3670 * and there may be space available to use. If there were no extent
3671 * or iunlinks, we can free up the entire log and set the tail_lsn to
3672 * be the last_sync_lsn. This was set in xlog_find_tail to be the
3673 * lsn of the last known good LR on disk. If there are extent frees
3674 * or iunlinks they will have some entries in the AIL; so we look at
3675 * the AIL to determine how to set the tail_lsn.
3676 */
3677 xlog_assign_tail_lsn(log->l_mp);
3678
3679 /*
3680 * Now that we've finished replaying all buffer and inode
3681 * updates, re-read in the superblock.
3682 */
3683 bp = xfs_getsb(log->l_mp, 0);
3684 XFS_BUF_UNDONE(bp);
3685 ASSERT(!(XFS_BUF_ISWRITE(bp)));
3686 ASSERT(!(XFS_BUF_ISDELAYWRITE(bp)));
3687 XFS_BUF_READ(bp);
3688 XFS_BUF_UNASYNC(bp);
3689 xfsbdstrat(log->l_mp, bp);
3690 error = xfs_buf_iowait(bp);
3691 if (error) {
3692 xfs_ioerror_alert("xlog_do_recover",
3693 log->l_mp, bp, XFS_BUF_ADDR(bp));
3694 ASSERT(0);
3695 xfs_buf_relse(bp);
3696 return error;
3697 }
3698
3699 /* Convert superblock from on-disk format */
3700 sbp = &log->l_mp->m_sb;
3701 xfs_sb_from_disk(sbp, XFS_BUF_TO_SBP(bp));
3702 ASSERT(sbp->sb_magicnum == XFS_SB_MAGIC);
3703 ASSERT(xfs_sb_good_version(sbp));
3704 xfs_buf_relse(bp);
3705
3706 /* We've re-read the superblock so re-initialize per-cpu counters */
3707 xfs_icsb_reinit_counters(log->l_mp);
3708
3709 xlog_recover_check_summary(log);
3710
3711 /* Normal transactions can now occur */
3712 log->l_flags &= ~XLOG_ACTIVE_RECOVERY;
3713 return 0;
3714}
3715
3716/*
3717 * Perform recovery and re-initialize some log variables in xlog_find_tail.
3718 *
3719 * Return error or zero.
3720 */
3721int
3722xlog_recover(
3723 xlog_t *log)
3724{
3725 xfs_daddr_t head_blk, tail_blk;
3726 int error;
3727
3728 /* find the tail of the log */
3729 if ((error = xlog_find_tail(log, &head_blk, &tail_blk)))
3730 return error;
3731
3732 if (tail_blk != head_blk) {
3733 /* There used to be a comment here:
3734 *
3735 * disallow recovery on read-only mounts. note -- mount
3736 * checks for ENOSPC and turns it into an intelligent
3737 * error message.
3738 * ...but this is no longer true. Now, unless you specify
3739 * NORECOVERY (in which case this function would never be
3740 * called), we just go ahead and recover. We do this all
3741 * under the vfs layer, so we can get away with it unless
3742 * the device itself is read-only, in which case we fail.
3743 */
3744 if ((error = xfs_dev_is_read_only(log->l_mp, "recovery"))) {
3745 return error;
3746 }
3747
3748 xfs_notice(log->l_mp, "Starting recovery (logdev: %s)",
3749 log->l_mp->m_logname ? log->l_mp->m_logname
3750 : "internal");
3751
3752 error = xlog_do_recover(log, head_blk, tail_blk);
3753 log->l_flags |= XLOG_RECOVERY_NEEDED;
3754 }
3755 return error;
3756}
3757
3758/*
3759 * In the first part of recovery we replay inodes and buffers and build
3760 * up the list of extent free items which need to be processed. Here
3761 * we process the extent free items and clean up the on disk unlinked
3762 * inode lists. This is separated from the first part of recovery so
3763 * that the root and real-time bitmap inodes can be read in from disk in
3764 * between the two stages. This is necessary so that we can free space
3765 * in the real-time portion of the file system.
3766 */
3767int
3768xlog_recover_finish(
3769 xlog_t *log)
3770{
3771 /*
3772 * Now we're ready to do the transactions needed for the
3773 * rest of recovery. Start with completing all the extent
3774 * free intent records and then process the unlinked inode
3775 * lists. At this point, we essentially run in normal mode
3776 * except that we're still performing recovery actions
3777 * rather than accepting new requests.
3778 */
3779 if (log->l_flags & XLOG_RECOVERY_NEEDED) {
3780 int error;
3781 error = xlog_recover_process_efis(log);
3782 if (error) {
3783 xfs_alert(log->l_mp, "Failed to recover EFIs");
3784 return error;
3785 }
3786 /*
3787 * Sync the log to get all the EFIs out of the AIL.
3788 * This isn't absolutely necessary, but it helps in
3789 * case the unlink transactions would have problems
3790 * pushing the EFIs out of the way.
3791 */
3792 xfs_log_force(log->l_mp, XFS_LOG_SYNC);
3793
3794 xlog_recover_process_iunlinks(log);
3795
3796 xlog_recover_check_summary(log);
3797
3798 xfs_notice(log->l_mp, "Ending recovery (logdev: %s)",
3799 log->l_mp->m_logname ? log->l_mp->m_logname
3800 : "internal");
3801 log->l_flags &= ~XLOG_RECOVERY_NEEDED;
3802 } else {
3803 xfs_info(log->l_mp, "Ending clean mount");
3804 }
3805 return 0;
3806}
3807
3808
3809#if defined(DEBUG)
3810/*
3811 * Read all of the agf and agi counters and check that they
3812 * are consistent with the superblock counters.
3813 */
3814void
3815xlog_recover_check_summary(
3816 xlog_t *log)
3817{
3818 xfs_mount_t *mp;
3819 xfs_agf_t *agfp;
3820 xfs_buf_t *agfbp;
3821 xfs_buf_t *agibp;
3822 xfs_agnumber_t agno;
3823 __uint64_t freeblks;
3824 __uint64_t itotal;
3825 __uint64_t ifree;
3826 int error;
3827
3828 mp = log->l_mp;
3829
3830 freeblks = 0LL;
3831 itotal = 0LL;
3832 ifree = 0LL;
3833 for (agno = 0; agno < mp->m_sb.sb_agcount; agno++) {
3834 error = xfs_read_agf(mp, NULL, agno, 0, &agfbp);
3835 if (error) {
3836 xfs_alert(mp, "%s agf read failed agno %d error %d",
3837 __func__, agno, error);
3838 } else {
3839 agfp = XFS_BUF_TO_AGF(agfbp);
3840 freeblks += be32_to_cpu(agfp->agf_freeblks) +
3841 be32_to_cpu(agfp->agf_flcount);
3842 xfs_buf_relse(agfbp);
3843 }
3844
3845 error = xfs_read_agi(mp, NULL, agno, &agibp);
3846 if (error) {
3847 xfs_alert(mp, "%s agi read failed agno %d error %d",
3848 __func__, agno, error);
3849 } else {
3850 struct xfs_agi *agi = XFS_BUF_TO_AGI(agibp);
3851
3852 itotal += be32_to_cpu(agi->agi_count);
3853 ifree += be32_to_cpu(agi->agi_freecount);
3854 xfs_buf_relse(agibp);
3855 }
3856 }
3857}
3858#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