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_mount.h"
14 #include "xfs_trans.h"
15 #include "xfs_buf_item.h"
16 #include "xfs_trans_priv.h"
17 #include "xfs_trace.h"
18 #include "xfs_log.h"
19 #include "xfs_log_priv.h"
20 #include "xfs_log_recover.h"
21 #include "xfs_error.h"
22 #include "xfs_inode.h"
23 #include "xfs_dir2.h"
24 #include "xfs_quota.h"
25
26 /*
27 * This is the number of entries in the l_buf_cancel_table used during
28 * recovery.
29 */
30 #define XLOG_BC_TABLE_SIZE 64
31
32 #define XLOG_BUF_CANCEL_BUCKET(log, blkno) \
33 ((log)->l_buf_cancel_table + ((uint64_t)blkno % XLOG_BC_TABLE_SIZE))
34
35 /*
36 * This structure is used during recovery to record the buf log items which
37 * have been canceled and should not be replayed.
38 */
39 struct xfs_buf_cancel {
40 xfs_daddr_t bc_blkno;
41 uint bc_len;
42 int bc_refcount;
43 struct list_head bc_list;
44 };
45
46 static struct xfs_buf_cancel *
47 xlog_find_buffer_cancelled(
48 struct xlog *log,
49 xfs_daddr_t blkno,
50 uint len)
51 {
52 struct list_head *bucket;
53 struct xfs_buf_cancel *bcp;
54
55 if (!log->l_buf_cancel_table)
56 return NULL;
57
58 bucket = XLOG_BUF_CANCEL_BUCKET(log, blkno);
59 list_for_each_entry(bcp, bucket, bc_list) {
60 if (bcp->bc_blkno == blkno && bcp->bc_len == len)
61 return bcp;
62 }
63
64 return NULL;
65 }
66
67 static bool
68 xlog_add_buffer_cancelled(
69 struct xlog *log,
70 xfs_daddr_t blkno,
71 uint len)
72 {
73 struct xfs_buf_cancel *bcp;
74
75 /*
76 * If we find an existing cancel record, this indicates that the buffer
77 * was cancelled multiple times. To ensure that during pass 2 we keep
78 * the record in the table until we reach its last occurrence in the
79 * log, a reference count is kept to tell how many times we expect to
80 * see this record during the second pass.
81 */
82 bcp = xlog_find_buffer_cancelled(log, blkno, len);
83 if (bcp) {
84 bcp->bc_refcount++;
85 return false;
86 }
87
88 bcp = kmalloc(sizeof(struct xfs_buf_cancel), GFP_KERNEL | __GFP_NOFAIL);
89 bcp->bc_blkno = blkno;
90 bcp->bc_len = len;
91 bcp->bc_refcount = 1;
92 list_add_tail(&bcp->bc_list, XLOG_BUF_CANCEL_BUCKET(log, blkno));
93 return true;
94 }
95
96 /*
97 * Check if there is and entry for blkno, len in the buffer cancel record table.
98 */
99 bool
100 xlog_is_buffer_cancelled(
101 struct xlog *log,
102 xfs_daddr_t blkno,
103 uint len)
104 {
105 return xlog_find_buffer_cancelled(log, blkno, len) != NULL;
106 }
107
108 /*
109 * Check if there is and entry for blkno, len in the buffer cancel record table,
110 * and decremented the reference count on it if there is one.
111 *
112 * Remove the cancel record once the refcount hits zero, so that if the same
113 * buffer is re-used again after its last cancellation we actually replay the
114 * changes made at that point.
115 */
116 static bool
117 xlog_put_buffer_cancelled(
118 struct xlog *log,
119 xfs_daddr_t blkno,
120 uint len)
121 {
122 struct xfs_buf_cancel *bcp;
123
124 bcp = xlog_find_buffer_cancelled(log, blkno, len);
125 if (!bcp) {
126 ASSERT(0);
127 return false;
128 }
129
130 if (--bcp->bc_refcount == 0) {
131 list_del(&bcp->bc_list);
132 kfree(bcp);
133 }
134 return true;
135 }
136
137 /* log buffer item recovery */
138
139 /*
140 * Sort buffer items for log recovery. Most buffer items should end up on the
141 * buffer list and are recovered first, with the following exceptions:
142 *
143 * 1. XFS_BLF_CANCEL buffers must be processed last because some log items
144 * might depend on the incor ecancellation record, and replaying a cancelled
145 * buffer item can remove the incore record.
146 *
147 * 2. XFS_BLF_INODE_BUF buffers are handled after most regular items so that
148 * we replay di_next_unlinked only after flushing the inode 'free' state
149 * to the inode buffer.
150 *
151 * See xlog_recover_reorder_trans for more details.
152 */
153 STATIC enum xlog_recover_reorder
154 xlog_recover_buf_reorder(
155 struct xlog_recover_item *item)
156 {
157 struct xfs_buf_log_format *buf_f = item->ri_buf[0].i_addr;
158
159 if (buf_f->blf_flags & XFS_BLF_CANCEL)
160 return XLOG_REORDER_CANCEL_LIST;
161 if (buf_f->blf_flags & XFS_BLF_INODE_BUF)
162 return XLOG_REORDER_INODE_BUFFER_LIST;
163 return XLOG_REORDER_BUFFER_LIST;
164 }
165
166 STATIC void
167 xlog_recover_buf_ra_pass2(
168 struct xlog *log,
169 struct xlog_recover_item *item)
170 {
171 struct xfs_buf_log_format *buf_f = item->ri_buf[0].i_addr;
172
173 xlog_buf_readahead(log, buf_f->blf_blkno, buf_f->blf_len, NULL);
174 }
175
176 /*
177 * Build up the table of buf cancel records so that we don't replay cancelled
178 * data in the second pass.
179 */
180 static int
181 xlog_recover_buf_commit_pass1(
182 struct xlog *log,
183 struct xlog_recover_item *item)
184 {
185 struct xfs_buf_log_format *bf = item->ri_buf[0].i_addr;
186
187 if (!xfs_buf_log_check_iovec(&item->ri_buf[0])) {
188 xfs_err(log->l_mp, "bad buffer log item size (%d)",
189 item->ri_buf[0].i_len);
190 return -EFSCORRUPTED;
191 }
192
193 if (!(bf->blf_flags & XFS_BLF_CANCEL))
194 trace_xfs_log_recover_buf_not_cancel(log, bf);
195 else if (xlog_add_buffer_cancelled(log, bf->blf_blkno, bf->blf_len))
196 trace_xfs_log_recover_buf_cancel_add(log, bf);
197 else
198 trace_xfs_log_recover_buf_cancel_ref_inc(log, bf);
199 return 0;
200 }
201
202 /*
203 * Validate the recovered buffer is of the correct type and attach the
204 * appropriate buffer operations to them for writeback. Magic numbers are in a
205 * few places:
206 * the first 16 bits of the buffer (inode buffer, dquot buffer),
207 * the first 32 bits of the buffer (most blocks),
208 * inside a struct xfs_da_blkinfo at the start of the buffer.
209 */
210 static void
211 xlog_recover_validate_buf_type(
212 struct xfs_mount *mp,
213 struct xfs_buf *bp,
214 struct xfs_buf_log_format *buf_f,
215 xfs_lsn_t current_lsn)
216 {
217 struct xfs_da_blkinfo *info = bp->b_addr;
218 uint32_t magic32;
219 uint16_t magic16;
220 uint16_t magicda;
221 char *warnmsg = NULL;
222
223 /*
224 * We can only do post recovery validation on items on CRC enabled
225 * fielsystems as we need to know when the buffer was written to be able
226 * to determine if we should have replayed the item. If we replay old
227 * metadata over a newer buffer, then it will enter a temporarily
228 * inconsistent state resulting in verification failures. Hence for now
229 * just avoid the verification stage for non-crc filesystems
230 */
231 if (!xfs_has_crc(mp))
232 return;
233
234 magic32 = be32_to_cpu(*(__be32 *)bp->b_addr);
235 magic16 = be16_to_cpu(*(__be16*)bp->b_addr);
236 magicda = be16_to_cpu(info->magic);
237 switch (xfs_blft_from_flags(buf_f)) {
238 case XFS_BLFT_BTREE_BUF:
239 switch (magic32) {
240 case XFS_ABTB_CRC_MAGIC:
241 case XFS_ABTB_MAGIC:
242 bp->b_ops = &xfs_bnobt_buf_ops;
243 break;
244 case XFS_ABTC_CRC_MAGIC:
245 case XFS_ABTC_MAGIC:
246 bp->b_ops = &xfs_cntbt_buf_ops;
247 break;
248 case XFS_IBT_CRC_MAGIC:
249 case XFS_IBT_MAGIC:
250 bp->b_ops = &xfs_inobt_buf_ops;
251 break;
252 case XFS_FIBT_CRC_MAGIC:
253 case XFS_FIBT_MAGIC:
254 bp->b_ops = &xfs_finobt_buf_ops;
255 break;
256 case XFS_BMAP_CRC_MAGIC:
257 case XFS_BMAP_MAGIC:
258 bp->b_ops = &xfs_bmbt_buf_ops;
259 break;
260 case XFS_RMAP_CRC_MAGIC:
261 bp->b_ops = &xfs_rmapbt_buf_ops;
262 break;
263 case XFS_REFC_CRC_MAGIC:
264 bp->b_ops = &xfs_refcountbt_buf_ops;
265 break;
266 default:
267 warnmsg = "Bad btree block magic!";
268 break;
269 }
270 break;
271 case XFS_BLFT_AGF_BUF:
272 if (magic32 != XFS_AGF_MAGIC) {
273 warnmsg = "Bad AGF block magic!";
274 break;
275 }
276 bp->b_ops = &xfs_agf_buf_ops;
277 break;
278 case XFS_BLFT_AGFL_BUF:
279 if (magic32 != XFS_AGFL_MAGIC) {
280 warnmsg = "Bad AGFL block magic!";
281 break;
282 }
283 bp->b_ops = &xfs_agfl_buf_ops;
284 break;
285 case XFS_BLFT_AGI_BUF:
286 if (magic32 != XFS_AGI_MAGIC) {
287 warnmsg = "Bad AGI block magic!";
288 break;
289 }
290 bp->b_ops = &xfs_agi_buf_ops;
291 break;
292 case XFS_BLFT_UDQUOT_BUF:
293 case XFS_BLFT_PDQUOT_BUF:
294 case XFS_BLFT_GDQUOT_BUF:
295 #ifdef CONFIG_XFS_QUOTA
296 if (magic16 != XFS_DQUOT_MAGIC) {
297 warnmsg = "Bad DQUOT block magic!";
298 break;
299 }
300 bp->b_ops = &xfs_dquot_buf_ops;
301 #else
302 xfs_alert(mp,
303 "Trying to recover dquots without QUOTA support built in!");
304 ASSERT(0);
305 #endif
306 break;
307 case XFS_BLFT_DINO_BUF:
308 if (magic16 != XFS_DINODE_MAGIC) {
309 warnmsg = "Bad INODE block magic!";
310 break;
311 }
312 bp->b_ops = &xfs_inode_buf_ops;
313 break;
314 case XFS_BLFT_SYMLINK_BUF:
315 if (magic32 != XFS_SYMLINK_MAGIC) {
316 warnmsg = "Bad symlink block magic!";
317 break;
318 }
319 bp->b_ops = &xfs_symlink_buf_ops;
320 break;
321 case XFS_BLFT_DIR_BLOCK_BUF:
322 if (magic32 != XFS_DIR2_BLOCK_MAGIC &&
323 magic32 != XFS_DIR3_BLOCK_MAGIC) {
324 warnmsg = "Bad dir block magic!";
325 break;
326 }
327 bp->b_ops = &xfs_dir3_block_buf_ops;
328 break;
329 case XFS_BLFT_DIR_DATA_BUF:
330 if (magic32 != XFS_DIR2_DATA_MAGIC &&
331 magic32 != XFS_DIR3_DATA_MAGIC) {
332 warnmsg = "Bad dir data magic!";
333 break;
334 }
335 bp->b_ops = &xfs_dir3_data_buf_ops;
336 break;
337 case XFS_BLFT_DIR_FREE_BUF:
338 if (magic32 != XFS_DIR2_FREE_MAGIC &&
339 magic32 != XFS_DIR3_FREE_MAGIC) {
340 warnmsg = "Bad dir3 free magic!";
341 break;
342 }
343 bp->b_ops = &xfs_dir3_free_buf_ops;
344 break;
345 case XFS_BLFT_DIR_LEAF1_BUF:
346 if (magicda != XFS_DIR2_LEAF1_MAGIC &&
347 magicda != XFS_DIR3_LEAF1_MAGIC) {
348 warnmsg = "Bad dir leaf1 magic!";
349 break;
350 }
351 bp->b_ops = &xfs_dir3_leaf1_buf_ops;
352 break;
353 case XFS_BLFT_DIR_LEAFN_BUF:
354 if (magicda != XFS_DIR2_LEAFN_MAGIC &&
355 magicda != XFS_DIR3_LEAFN_MAGIC) {
356 warnmsg = "Bad dir leafn magic!";
357 break;
358 }
359 bp->b_ops = &xfs_dir3_leafn_buf_ops;
360 break;
361 case XFS_BLFT_DA_NODE_BUF:
362 if (magicda != XFS_DA_NODE_MAGIC &&
363 magicda != XFS_DA3_NODE_MAGIC) {
364 warnmsg = "Bad da node magic!";
365 break;
366 }
367 bp->b_ops = &xfs_da3_node_buf_ops;
368 break;
369 case XFS_BLFT_ATTR_LEAF_BUF:
370 if (magicda != XFS_ATTR_LEAF_MAGIC &&
371 magicda != XFS_ATTR3_LEAF_MAGIC) {
372 warnmsg = "Bad attr leaf magic!";
373 break;
374 }
375 bp->b_ops = &xfs_attr3_leaf_buf_ops;
376 break;
377 case XFS_BLFT_ATTR_RMT_BUF:
378 if (magic32 != XFS_ATTR3_RMT_MAGIC) {
379 warnmsg = "Bad attr remote magic!";
380 break;
381 }
382 bp->b_ops = &xfs_attr3_rmt_buf_ops;
383 break;
384 case XFS_BLFT_SB_BUF:
385 if (magic32 != XFS_SB_MAGIC) {
386 warnmsg = "Bad SB block magic!";
387 break;
388 }
389 bp->b_ops = &xfs_sb_buf_ops;
390 break;
391 #ifdef CONFIG_XFS_RT
392 case XFS_BLFT_RTBITMAP_BUF:
393 case XFS_BLFT_RTSUMMARY_BUF:
394 /* no magic numbers for verification of RT buffers */
395 bp->b_ops = &xfs_rtbuf_ops;
396 break;
397 #endif /* CONFIG_XFS_RT */
398 default:
399 xfs_warn(mp, "Unknown buffer type %d!",
400 xfs_blft_from_flags(buf_f));
401 break;
402 }
403
404 /*
405 * Nothing else to do in the case of a NULL current LSN as this means
406 * the buffer is more recent than the change in the log and will be
407 * skipped.
408 */
409 if (current_lsn == NULLCOMMITLSN)
410 return;
411
412 if (warnmsg) {
413 xfs_warn(mp, warnmsg);
414 ASSERT(0);
415 }
416
417 /*
418 * We must update the metadata LSN of the buffer as it is written out to
419 * ensure that older transactions never replay over this one and corrupt
420 * the buffer. This can occur if log recovery is interrupted at some
421 * point after the current transaction completes, at which point a
422 * subsequent mount starts recovery from the beginning.
423 *
424 * Write verifiers update the metadata LSN from log items attached to
425 * the buffer. Therefore, initialize a bli purely to carry the LSN to
426 * the verifier.
427 */
428 if (bp->b_ops) {
429 struct xfs_buf_log_item *bip;
430
431 bp->b_flags |= _XBF_LOGRECOVERY;
432 xfs_buf_item_init(bp, mp);
433 bip = bp->b_log_item;
434 bip->bli_item.li_lsn = current_lsn;
435 }
436 }
437
438 /*
439 * Perform a 'normal' buffer recovery. Each logged region of the
440 * buffer should be copied over the corresponding region in the
441 * given buffer. The bitmap in the buf log format structure indicates
442 * where to place the logged data.
443 */
444 STATIC void
445 xlog_recover_do_reg_buffer(
446 struct xfs_mount *mp,
447 struct xlog_recover_item *item,
448 struct xfs_buf *bp,
449 struct xfs_buf_log_format *buf_f,
450 xfs_lsn_t current_lsn)
451 {
452 int i;
453 int bit;
454 int nbits;
455 xfs_failaddr_t fa;
456 const size_t size_disk_dquot = sizeof(struct xfs_disk_dquot);
457
458 trace_xfs_log_recover_buf_reg_buf(mp->m_log, buf_f);
459
460 bit = 0;
461 i = 1; /* 0 is the buf format structure */
462 while (1) {
463 bit = xfs_next_bit(buf_f->blf_data_map,
464 buf_f->blf_map_size, bit);
465 if (bit == -1)
466 break;
467 nbits = xfs_contig_bits(buf_f->blf_data_map,
468 buf_f->blf_map_size, bit);
469 ASSERT(nbits > 0);
470 ASSERT(item->ri_buf[i].i_addr != NULL);
471 ASSERT(item->ri_buf[i].i_len % XFS_BLF_CHUNK == 0);
472 ASSERT(BBTOB(bp->b_length) >=
473 ((uint)bit << XFS_BLF_SHIFT) + (nbits << XFS_BLF_SHIFT));
474
475 /*
476 * The dirty regions logged in the buffer, even though
477 * contiguous, may span multiple chunks. This is because the
478 * dirty region may span a physical page boundary in a buffer
479 * and hence be split into two separate vectors for writing into
480 * the log. Hence we need to trim nbits back to the length of
481 * the current region being copied out of the log.
482 */
483 if (item->ri_buf[i].i_len < (nbits << XFS_BLF_SHIFT))
484 nbits = item->ri_buf[i].i_len >> XFS_BLF_SHIFT;
485
486 /*
487 * Do a sanity check if this is a dquot buffer. Just checking
488 * the first dquot in the buffer should do. XXXThis is
489 * probably a good thing to do for other buf types also.
490 */
491 fa = NULL;
492 if (buf_f->blf_flags &
493 (XFS_BLF_UDQUOT_BUF|XFS_BLF_PDQUOT_BUF|XFS_BLF_GDQUOT_BUF)) {
494 if (item->ri_buf[i].i_addr == NULL) {
495 xfs_alert(mp,
496 "XFS: NULL dquot in %s.", __func__);
497 goto next;
498 }
499 if (item->ri_buf[i].i_len < size_disk_dquot) {
500 xfs_alert(mp,
501 "XFS: dquot too small (%d) in %s.",
502 item->ri_buf[i].i_len, __func__);
503 goto next;
504 }
505 fa = xfs_dquot_verify(mp, item->ri_buf[i].i_addr, -1);
506 if (fa) {
507 xfs_alert(mp,
508 "dquot corrupt at %pS trying to replay into block 0x%llx",
509 fa, xfs_buf_daddr(bp));
510 goto next;
511 }
512 }
513
514 memcpy(xfs_buf_offset(bp,
515 (uint)bit << XFS_BLF_SHIFT), /* dest */
516 item->ri_buf[i].i_addr, /* source */
517 nbits<<XFS_BLF_SHIFT); /* length */
518 next:
519 i++;
520 bit += nbits;
521 }
522
523 /* Shouldn't be any more regions */
524 ASSERT(i == item->ri_total);
525
526 xlog_recover_validate_buf_type(mp, bp, buf_f, current_lsn);
527 }
528
529 /*
530 * Perform a dquot buffer recovery.
531 * Simple algorithm: if we have found a QUOTAOFF log item of the same type
532 * (ie. USR or GRP), then just toss this buffer away; don't recover it.
533 * Else, treat it as a regular buffer and do recovery.
534 *
535 * Return false if the buffer was tossed and true if we recovered the buffer to
536 * indicate to the caller if the buffer needs writing.
537 */
538 STATIC bool
539 xlog_recover_do_dquot_buffer(
540 struct xfs_mount *mp,
541 struct xlog *log,
542 struct xlog_recover_item *item,
543 struct xfs_buf *bp,
544 struct xfs_buf_log_format *buf_f)
545 {
546 uint type;
547
548 trace_xfs_log_recover_buf_dquot_buf(log, buf_f);
549
550 /*
551 * Filesystems are required to send in quota flags at mount time.
552 */
553 if (!mp->m_qflags)
554 return false;
555
556 type = 0;
557 if (buf_f->blf_flags & XFS_BLF_UDQUOT_BUF)
558 type |= XFS_DQTYPE_USER;
559 if (buf_f->blf_flags & XFS_BLF_PDQUOT_BUF)
560 type |= XFS_DQTYPE_PROJ;
561 if (buf_f->blf_flags & XFS_BLF_GDQUOT_BUF)
562 type |= XFS_DQTYPE_GROUP;
563 /*
564 * This type of quotas was turned off, so ignore this buffer
565 */
566 if (log->l_quotaoffs_flag & type)
567 return false;
568
569 xlog_recover_do_reg_buffer(mp, item, bp, buf_f, NULLCOMMITLSN);
570 return true;
571 }
572
573 /*
574 * Perform recovery for a buffer full of inodes. In these buffers, the only
575 * data which should be recovered is that which corresponds to the
576 * di_next_unlinked pointers in the on disk inode structures. The rest of the
577 * data for the inodes is always logged through the inodes themselves rather
578 * than the inode buffer and is recovered in xlog_recover_inode_pass2().
579 *
580 * The only time when buffers full of inodes are fully recovered is when the
581 * buffer is full of newly allocated inodes. In this case the buffer will
582 * not be marked as an inode buffer and so will be sent to
583 * xlog_recover_do_reg_buffer() below during recovery.
584 */
585 STATIC int
586 xlog_recover_do_inode_buffer(
587 struct xfs_mount *mp,
588 struct xlog_recover_item *item,
589 struct xfs_buf *bp,
590 struct xfs_buf_log_format *buf_f)
591 {
592 int i;
593 int item_index = 0;
594 int bit = 0;
595 int nbits = 0;
596 int reg_buf_offset = 0;
597 int reg_buf_bytes = 0;
598 int next_unlinked_offset;
599 int inodes_per_buf;
600 xfs_agino_t *logged_nextp;
601 xfs_agino_t *buffer_nextp;
602
603 trace_xfs_log_recover_buf_inode_buf(mp->m_log, buf_f);
604
605 /*
606 * Post recovery validation only works properly on CRC enabled
607 * filesystems.
608 */
609 if (xfs_has_crc(mp))
610 bp->b_ops = &xfs_inode_buf_ops;
611
612 inodes_per_buf = BBTOB(bp->b_length) >> mp->m_sb.sb_inodelog;
613 for (i = 0; i < inodes_per_buf; i++) {
614 next_unlinked_offset = (i * mp->m_sb.sb_inodesize) +
615 offsetof(struct xfs_dinode, di_next_unlinked);
616
617 while (next_unlinked_offset >=
618 (reg_buf_offset + reg_buf_bytes)) {
619 /*
620 * The next di_next_unlinked field is beyond
621 * the current logged region. Find the next
622 * logged region that contains or is beyond
623 * the current di_next_unlinked field.
624 */
625 bit += nbits;
626 bit = xfs_next_bit(buf_f->blf_data_map,
627 buf_f->blf_map_size, bit);
628
629 /*
630 * If there are no more logged regions in the
631 * buffer, then we're done.
632 */
633 if (bit == -1)
634 return 0;
635
636 nbits = xfs_contig_bits(buf_f->blf_data_map,
637 buf_f->blf_map_size, bit);
638 ASSERT(nbits > 0);
639 reg_buf_offset = bit << XFS_BLF_SHIFT;
640 reg_buf_bytes = nbits << XFS_BLF_SHIFT;
641 item_index++;
642 }
643
644 /*
645 * If the current logged region starts after the current
646 * di_next_unlinked field, then move on to the next
647 * di_next_unlinked field.
648 */
649 if (next_unlinked_offset < reg_buf_offset)
650 continue;
651
652 ASSERT(item->ri_buf[item_index].i_addr != NULL);
653 ASSERT((item->ri_buf[item_index].i_len % XFS_BLF_CHUNK) == 0);
654 ASSERT((reg_buf_offset + reg_buf_bytes) <= BBTOB(bp->b_length));
655
656 /*
657 * The current logged region contains a copy of the
658 * current di_next_unlinked field. Extract its value
659 * and copy it to the buffer copy.
660 */
661 logged_nextp = item->ri_buf[item_index].i_addr +
662 next_unlinked_offset - reg_buf_offset;
663 if (XFS_IS_CORRUPT(mp, *logged_nextp == 0)) {
664 xfs_alert(mp,
665 "Bad inode buffer log record (ptr = "PTR_FMT", bp = "PTR_FMT"). "
666 "Trying to replay bad (0) inode di_next_unlinked field.",
667 item, bp);
668 return -EFSCORRUPTED;
669 }
670
671 buffer_nextp = xfs_buf_offset(bp, next_unlinked_offset);
672 *buffer_nextp = *logged_nextp;
673
674 /*
675 * If necessary, recalculate the CRC in the on-disk inode. We
676 * have to leave the inode in a consistent state for whoever
677 * reads it next....
678 */
679 xfs_dinode_calc_crc(mp,
680 xfs_buf_offset(bp, i * mp->m_sb.sb_inodesize));
681
682 }
683
684 return 0;
685 }
686
687 /*
688 * V5 filesystems know the age of the buffer on disk being recovered. We can
689 * have newer objects on disk than we are replaying, and so for these cases we
690 * don't want to replay the current change as that will make the buffer contents
691 * temporarily invalid on disk.
692 *
693 * The magic number might not match the buffer type we are going to recover
694 * (e.g. reallocated blocks), so we ignore the xfs_buf_log_format flags. Hence
695 * extract the LSN of the existing object in the buffer based on it's current
696 * magic number. If we don't recognise the magic number in the buffer, then
697 * return a LSN of -1 so that the caller knows it was an unrecognised block and
698 * so can recover the buffer.
699 *
700 * Note: we cannot rely solely on magic number matches to determine that the
701 * buffer has a valid LSN - we also need to verify that it belongs to this
702 * filesystem, so we need to extract the object's LSN and compare it to that
703 * which we read from the superblock. If the UUIDs don't match, then we've got a
704 * stale metadata block from an old filesystem instance that we need to recover
705 * over the top of.
706 */
707 static xfs_lsn_t
708 xlog_recover_get_buf_lsn(
709 struct xfs_mount *mp,
710 struct xfs_buf *bp,
711 struct xfs_buf_log_format *buf_f)
712 {
713 uint32_t magic32;
714 uint16_t magic16;
715 uint16_t magicda;
716 void *blk = bp->b_addr;
717 uuid_t *uuid;
718 xfs_lsn_t lsn = -1;
719 uint16_t blft;
720
721 /* v4 filesystems always recover immediately */
722 if (!xfs_has_crc(mp))
723 goto recover_immediately;
724
725 /*
726 * realtime bitmap and summary file blocks do not have magic numbers or
727 * UUIDs, so we must recover them immediately.
728 */
729 blft = xfs_blft_from_flags(buf_f);
730 if (blft == XFS_BLFT_RTBITMAP_BUF || blft == XFS_BLFT_RTSUMMARY_BUF)
731 goto recover_immediately;
732
733 magic32 = be32_to_cpu(*(__be32 *)blk);
734 switch (magic32) {
735 case XFS_ABTB_CRC_MAGIC:
736 case XFS_ABTC_CRC_MAGIC:
737 case XFS_ABTB_MAGIC:
738 case XFS_ABTC_MAGIC:
739 case XFS_RMAP_CRC_MAGIC:
740 case XFS_REFC_CRC_MAGIC:
741 case XFS_FIBT_CRC_MAGIC:
742 case XFS_FIBT_MAGIC:
743 case XFS_IBT_CRC_MAGIC:
744 case XFS_IBT_MAGIC: {
745 struct xfs_btree_block *btb = blk;
746
747 lsn = be64_to_cpu(btb->bb_u.s.bb_lsn);
748 uuid = &btb->bb_u.s.bb_uuid;
749 break;
750 }
751 case XFS_BMAP_CRC_MAGIC:
752 case XFS_BMAP_MAGIC: {
753 struct xfs_btree_block *btb = blk;
754
755 lsn = be64_to_cpu(btb->bb_u.l.bb_lsn);
756 uuid = &btb->bb_u.l.bb_uuid;
757 break;
758 }
759 case XFS_AGF_MAGIC:
760 lsn = be64_to_cpu(((struct xfs_agf *)blk)->agf_lsn);
761 uuid = &((struct xfs_agf *)blk)->agf_uuid;
762 break;
763 case XFS_AGFL_MAGIC:
764 lsn = be64_to_cpu(((struct xfs_agfl *)blk)->agfl_lsn);
765 uuid = &((struct xfs_agfl *)blk)->agfl_uuid;
766 break;
767 case XFS_AGI_MAGIC:
768 lsn = be64_to_cpu(((struct xfs_agi *)blk)->agi_lsn);
769 uuid = &((struct xfs_agi *)blk)->agi_uuid;
770 break;
771 case XFS_SYMLINK_MAGIC:
772 lsn = be64_to_cpu(((struct xfs_dsymlink_hdr *)blk)->sl_lsn);
773 uuid = &((struct xfs_dsymlink_hdr *)blk)->sl_uuid;
774 break;
775 case XFS_DIR3_BLOCK_MAGIC:
776 case XFS_DIR3_DATA_MAGIC:
777 case XFS_DIR3_FREE_MAGIC:
778 lsn = be64_to_cpu(((struct xfs_dir3_blk_hdr *)blk)->lsn);
779 uuid = &((struct xfs_dir3_blk_hdr *)blk)->uuid;
780 break;
781 case XFS_ATTR3_RMT_MAGIC:
782 /*
783 * Remote attr blocks are written synchronously, rather than
784 * being logged. That means they do not contain a valid LSN
785 * (i.e. transactionally ordered) in them, and hence any time we
786 * see a buffer to replay over the top of a remote attribute
787 * block we should simply do so.
788 */
789 goto recover_immediately;
790 case XFS_SB_MAGIC:
791 /*
792 * superblock uuids are magic. We may or may not have a
793 * sb_meta_uuid on disk, but it will be set in the in-core
794 * superblock. We set the uuid pointer for verification
795 * according to the superblock feature mask to ensure we check
796 * the relevant UUID in the superblock.
797 */
798 lsn = be64_to_cpu(((struct xfs_dsb *)blk)->sb_lsn);
799 if (xfs_has_metauuid(mp))
800 uuid = &((struct xfs_dsb *)blk)->sb_meta_uuid;
801 else
802 uuid = &((struct xfs_dsb *)blk)->sb_uuid;
803 break;
804 default:
805 break;
806 }
807
808 if (lsn != (xfs_lsn_t)-1) {
809 if (!uuid_equal(&mp->m_sb.sb_meta_uuid, uuid))
810 goto recover_immediately;
811 return lsn;
812 }
813
814 magicda = be16_to_cpu(((struct xfs_da_blkinfo *)blk)->magic);
815 switch (magicda) {
816 case XFS_DIR3_LEAF1_MAGIC:
817 case XFS_DIR3_LEAFN_MAGIC:
818 case XFS_ATTR3_LEAF_MAGIC:
819 case XFS_DA3_NODE_MAGIC:
820 lsn = be64_to_cpu(((struct xfs_da3_blkinfo *)blk)->lsn);
821 uuid = &((struct xfs_da3_blkinfo *)blk)->uuid;
822 break;
823 default:
824 break;
825 }
826
827 if (lsn != (xfs_lsn_t)-1) {
828 if (!uuid_equal(&mp->m_sb.sb_meta_uuid, uuid))
829 goto recover_immediately;
830 return lsn;
831 }
832
833 /*
834 * We do individual object checks on dquot and inode buffers as they
835 * have their own individual LSN records. Also, we could have a stale
836 * buffer here, so we have to at least recognise these buffer types.
837 *
838 * A notd complexity here is inode unlinked list processing - it logs
839 * the inode directly in the buffer, but we don't know which inodes have
840 * been modified, and there is no global buffer LSN. Hence we need to
841 * recover all inode buffer types immediately. This problem will be
842 * fixed by logical logging of the unlinked list modifications.
843 */
844 magic16 = be16_to_cpu(*(__be16 *)blk);
845 switch (magic16) {
846 case XFS_DQUOT_MAGIC:
847 case XFS_DINODE_MAGIC:
848 goto recover_immediately;
849 default:
850 break;
851 }
852
853 /* unknown buffer contents, recover immediately */
854
855 recover_immediately:
856 return (xfs_lsn_t)-1;
857
858 }
859
860 /*
861 * This routine replays a modification made to a buffer at runtime.
862 * There are actually two types of buffer, regular and inode, which
863 * are handled differently. Inode buffers are handled differently
864 * in that we only recover a specific set of data from them, namely
865 * the inode di_next_unlinked fields. This is because all other inode
866 * data is actually logged via inode records and any data we replay
867 * here which overlaps that may be stale.
868 *
869 * When meta-data buffers are freed at run time we log a buffer item
870 * with the XFS_BLF_CANCEL bit set to indicate that previous copies
871 * of the buffer in the log should not be replayed at recovery time.
872 * This is so that if the blocks covered by the buffer are reused for
873 * file data before we crash we don't end up replaying old, freed
874 * meta-data into a user's file.
875 *
876 * To handle the cancellation of buffer log items, we make two passes
877 * over the log during recovery. During the first we build a table of
878 * those buffers which have been cancelled, and during the second we
879 * only replay those buffers which do not have corresponding cancel
880 * records in the table. See xlog_recover_buf_pass[1,2] above
881 * for more details on the implementation of the table of cancel records.
882 */
883 STATIC int
884 xlog_recover_buf_commit_pass2(
885 struct xlog *log,
886 struct list_head *buffer_list,
887 struct xlog_recover_item *item,
888 xfs_lsn_t current_lsn)
889 {
890 struct xfs_buf_log_format *buf_f = item->ri_buf[0].i_addr;
891 struct xfs_mount *mp = log->l_mp;
892 struct xfs_buf *bp;
893 int error;
894 uint buf_flags;
895 xfs_lsn_t lsn;
896
897 /*
898 * In this pass we only want to recover all the buffers which have
899 * not been cancelled and are not cancellation buffers themselves.
900 */
901 if (buf_f->blf_flags & XFS_BLF_CANCEL) {
902 if (xlog_put_buffer_cancelled(log, buf_f->blf_blkno,
903 buf_f->blf_len))
904 goto cancelled;
905 } else {
906
907 if (xlog_is_buffer_cancelled(log, buf_f->blf_blkno,
908 buf_f->blf_len))
909 goto cancelled;
910 }
911
912 trace_xfs_log_recover_buf_recover(log, buf_f);
913
914 buf_flags = 0;
915 if (buf_f->blf_flags & XFS_BLF_INODE_BUF)
916 buf_flags |= XBF_UNMAPPED;
917
918 error = xfs_buf_read(mp->m_ddev_targp, buf_f->blf_blkno, buf_f->blf_len,
919 buf_flags, &bp, NULL);
920 if (error)
921 return error;
922
923 /*
924 * Recover the buffer only if we get an LSN from it and it's less than
925 * the lsn of the transaction we are replaying.
926 *
927 * Note that we have to be extremely careful of readahead here.
928 * Readahead does not attach verfiers to the buffers so if we don't
929 * actually do any replay after readahead because of the LSN we found
930 * in the buffer if more recent than that current transaction then we
931 * need to attach the verifier directly. Failure to do so can lead to
932 * future recovery actions (e.g. EFI and unlinked list recovery) can
933 * operate on the buffers and they won't get the verifier attached. This
934 * can lead to blocks on disk having the correct content but a stale
935 * CRC.
936 *
937 * It is safe to assume these clean buffers are currently up to date.
938 * If the buffer is dirtied by a later transaction being replayed, then
939 * the verifier will be reset to match whatever recover turns that
940 * buffer into.
941 */
942 lsn = xlog_recover_get_buf_lsn(mp, bp, buf_f);
943 if (lsn && lsn != -1 && XFS_LSN_CMP(lsn, current_lsn) >= 0) {
944 trace_xfs_log_recover_buf_skip(log, buf_f);
945 xlog_recover_validate_buf_type(mp, bp, buf_f, NULLCOMMITLSN);
946
947 /*
948 * We're skipping replay of this buffer log item due to the log
949 * item LSN being behind the ondisk buffer. Verify the buffer
950 * contents since we aren't going to run the write verifier.
951 */
952 if (bp->b_ops) {
953 bp->b_ops->verify_read(bp);
954 error = bp->b_error;
955 }
956 goto out_release;
957 }
958
959 if (buf_f->blf_flags & XFS_BLF_INODE_BUF) {
960 error = xlog_recover_do_inode_buffer(mp, item, bp, buf_f);
961 if (error)
962 goto out_release;
963 } else if (buf_f->blf_flags &
964 (XFS_BLF_UDQUOT_BUF|XFS_BLF_PDQUOT_BUF|XFS_BLF_GDQUOT_BUF)) {
965 bool dirty;
966
967 dirty = xlog_recover_do_dquot_buffer(mp, log, item, bp, buf_f);
968 if (!dirty)
969 goto out_release;
970 } else {
971 xlog_recover_do_reg_buffer(mp, item, bp, buf_f, current_lsn);
972 }
973
974 /*
975 * Perform delayed write on the buffer. Asynchronous writes will be
976 * slower when taking into account all the buffers to be flushed.
977 *
978 * Also make sure that only inode buffers with good sizes stay in
979 * the buffer cache. The kernel moves inodes in buffers of 1 block
980 * or inode_cluster_size bytes, whichever is bigger. The inode
981 * buffers in the log can be a different size if the log was generated
982 * by an older kernel using unclustered inode buffers or a newer kernel
983 * running with a different inode cluster size. Regardless, if
984 * the inode buffer size isn't max(blocksize, inode_cluster_size)
985 * for *our* value of inode_cluster_size, then we need to keep
986 * the buffer out of the buffer cache so that the buffer won't
987 * overlap with future reads of those inodes.
988 */
989 if (XFS_DINODE_MAGIC ==
990 be16_to_cpu(*((__be16 *)xfs_buf_offset(bp, 0))) &&
991 (BBTOB(bp->b_length) != M_IGEO(log->l_mp)->inode_cluster_size)) {
992 xfs_buf_stale(bp);
993 error = xfs_bwrite(bp);
994 } else {
995 ASSERT(bp->b_mount == mp);
996 bp->b_flags |= _XBF_LOGRECOVERY;
997 xfs_buf_delwri_queue(bp, buffer_list);
998 }
999
1000 out_release:
1001 xfs_buf_relse(bp);
1002 return error;
1003 cancelled:
1004 trace_xfs_log_recover_buf_cancel(log, buf_f);
1005 return 0;
1006 }
1007
1008 const struct xlog_recover_item_ops xlog_buf_item_ops = {
1009 .item_type = XFS_LI_BUF,
1010 .reorder = xlog_recover_buf_reorder,
1011 .ra_pass2 = xlog_recover_buf_ra_pass2,
1012 .commit_pass1 = xlog_recover_buf_commit_pass1,
1013 .commit_pass2 = xlog_recover_buf_commit_pass2,
1014 };
1015
1016 #ifdef DEBUG
1017 void
1018 xlog_check_buf_cancel_table(
1019 struct xlog *log)
1020 {
1021 int i;
1022
1023 for (i = 0; i < XLOG_BC_TABLE_SIZE; i++)
1024 ASSERT(list_empty(&log->l_buf_cancel_table[i]));
1025 }
1026 #endif
1027
1028 int
1029 xlog_alloc_buf_cancel_table(
1030 struct xlog *log)
1031 {
1032 void *p;
1033 int i;
1034
1035 ASSERT(log->l_buf_cancel_table == NULL);
1036
1037 p = kmalloc_array(XLOG_BC_TABLE_SIZE, sizeof(struct list_head),
1038 GFP_KERNEL);
1039 if (!p)
1040 return -ENOMEM;
1041
1042 log->l_buf_cancel_table = p;
1043 for (i = 0; i < XLOG_BC_TABLE_SIZE; i++)
1044 INIT_LIST_HEAD(&log->l_buf_cancel_table[i]);
1045
1046 return 0;
1047 }
1048
1049 void
1050 xlog_free_buf_cancel_table(
1051 struct xlog *log)
1052 {
1053 int i;
1054
1055 if (!log->l_buf_cancel_table)
1056 return;
1057
1058 for (i = 0; i < XLOG_BC_TABLE_SIZE; i++) {
1059 struct xfs_buf_cancel *bc;
1060
1061 while ((bc = list_first_entry_or_null(
1062 &log->l_buf_cancel_table[i],
1063 struct xfs_buf_cancel, bc_list))) {
1064 list_del(&bc->bc_list);
1065 kfree(bc);
1066 }
1067 }
1068
1069 kfree(log->l_buf_cancel_table);
1070 log->l_buf_cancel_table = NULL;
1071 }
1072
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