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 | |
34 | STATIC int |
35 | xlog_find_zeroed( |
36 | struct xlog *, |
37 | xfs_daddr_t *); |
38 | STATIC int |
39 | xlog_clear_stale_blocks( |
40 | struct xlog *, |
41 | xfs_lsn_t); |
42 | STATIC int |
43 | xlog_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 | */ |
55 | static inline bool |
56 | xlog_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 | */ |
72 | static char * |
73 | xlog_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(size: 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 | */ |
111 | static inline unsigned int |
112 | xlog_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 | |
119 | static int |
120 | xlog_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(bdev: log->l_targ->bt_bdev, sector: log->l_logBBstart + blk_no, |
141 | count: 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 | |
151 | STATIC int |
152 | xlog_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, op: REQ_OP_READ); |
159 | } |
160 | |
161 | STATIC int |
162 | xlog_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, op: REQ_OP_READ); |
172 | if (!error) |
173 | *offset = data + xlog_align(log, blk_no); |
174 | return error; |
175 | } |
176 | |
177 | STATIC int |
178 | xlog_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, op: REQ_OP_WRITE); |
185 | } |
186 | |
187 | #ifdef DEBUG |
188 | /* |
189 | * dump debug superblock and log record information |
190 | */ |
191 | STATIC void |
192 | ( |
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 | */ |
208 | STATIC int |
209 | ( |
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 | */ |
239 | STATIC int |
240 | ( |
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(uuid: &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 | */ |
268 | STATIC int |
269 | xlog_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, blk_no: mid_blk, nbblks: 1, data: buffer, offset: &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 | */ |
311 | STATIC int |
312 | xlog_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, nbblks: 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, blk_no: i, nbblks: bcount, data: buffer, offset: &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 | |
363 | out: |
364 | kmem_free(ptr: buffer); |
365 | return error; |
366 | } |
367 | |
368 | static inline int |
369 | xlog_logrec_hblks(struct xlog *log, struct xlog_rec_header *rh) |
370 | { |
371 | if (xfs_has_logv2(mp: 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 | */ |
393 | STATIC int |
394 | xlog_find_verify_log_record( |
395 | struct xlog *log, |
396 | xfs_daddr_t start_blk, |
397 | xfs_daddr_t *last_blk, |
398 | int ) |
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, nbblks: num_blks); |
412 | if (!buffer) { |
413 | buffer = xlog_alloc_buffer(log, nbblks: 1); |
414 | if (!buffer) |
415 | return -ENOMEM; |
416 | smallmem = 1; |
417 | } else { |
418 | error = xlog_bread(log, blk_no: start_blk, nbblks: num_blks, data: buffer, offset: &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, blk_no: i, nbblks: 1, data: buffer, offset: &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 | |
479 | out: |
480 | kmem_free(ptr: 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 | */ |
497 | STATIC int |
498 | xlog_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, nbblks: 1); |
533 | if (!buffer) |
534 | return -ENOMEM; |
535 | |
536 | error = xlog_bread(log, blk_no: 0, nbblks: 1, data: buffer, offset: &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, blk_no: last_blk, nbblks: 1, data: buffer, offset: &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, last_blk: &head_blk, |
614 | cycle: 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, nbblks: num_scan_bblks, |
635 | stop_on_cycle_no: stop_on_cycle, new_blk: &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 | nbblks: num_scan_bblks - (int)head_blk, |
672 | stop_on_cycle_no: (stop_on_cycle - 1), new_blk: &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, nbblks: (int)head_blk, |
688 | stop_on_cycle_no: stop_on_cycle, new_blk: &new_blk))) |
689 | goto out_free_buffer; |
690 | if (new_blk != -1) |
691 | head_blk = new_blk; |
692 | } |
693 | |
694 | validate_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, last_blk: &head_blk, extra_bblks: 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, last_blk: &head_blk, extra_bblks: 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 | last_blk: &new_blk, extra_bblks: (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 | kmem_free(ptr: 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 | |
747 | out_free_buffer: |
748 | kmem_free(ptr: 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 | */ |
762 | STATIC int |
763 | xlog_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, blk_no: i, nbblks: 1, data: buffer, offset: &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, blk_no: i, nbblks: 1, data: buffer, offset: &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 | |
823 | out_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 | */ |
836 | STATIC int |
837 | xlog_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, blk_no: i, nbblks: 1, data: buffer, offset: &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, blk_no: i, nbblks: 1, data: buffer, offset: &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 | |
896 | out_error: |
897 | return error; |
898 | } |
899 | |
900 | /* |
901 | * Calculate distance from head to tail (i.e., unused space in the log). |
902 | */ |
903 | static inline int |
904 | xlog_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 | */ |
934 | STATIC int |
935 | xlog_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, nbblks: 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: *tail_blk, count: 1, buffer, |
958 | rblk: &tmp_tail, rhead: &thead, wrapped: &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, tail_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, tail_blk: first_bad, count: 2, |
987 | buffer, rblk: &tmp_tail, rhead: &thead, wrapped: &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); |
1001 | out: |
1002 | kmem_free(ptr: 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 | */ |
1019 | STATIC int |
1020 | xlog_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, nbblks: 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 | kmem_free(ptr: 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, head_blk: first_bad, tail_blk: *tail_blk, count: 1, |
1079 | buffer, rblk: 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: *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 | */ |
1116 | static inline xfs_daddr_t |
1117 | xlog_wrap_logbno( |
1118 | struct xlog *log, |
1119 | xfs_daddr_t bno) |
1120 | { |
1121 | int mod; |
1122 | |
1123 | div_s64_rem(dividend: bno, divisor: log->l_logBBsize, remainder: &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 | */ |
1132 | static int |
1133 | xlog_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 *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, rh: rhead); |
1161 | after_umount_blk = xlog_wrap_logbno(log, |
1162 | bno: 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, bno: rhead_blk + hblks); |
1167 | error = xlog_bread(log, blk_no: umount_data_blk, nbblks: 1, data: buffer, offset: &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(lsn: &log->l_tail_lsn, |
1179 | cycle: log->l_curr_cycle, block: after_umount_blk); |
1180 | xlog_assign_atomic_lsn(lsn: &log->l_last_sync_lsn, |
1181 | cycle: log->l_curr_cycle, block: after_umount_blk); |
1182 | *tail_blk = after_umount_blk; |
1183 | |
1184 | *clean = true; |
1185 | } |
1186 | } |
1187 | |
1188 | return 0; |
1189 | } |
1190 | |
1191 | static void |
1192 | xlog_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(v: &log->l_tail_lsn, be64_to_cpu(rhead->h_tail_lsn)); |
1215 | atomic64_set(v: &log->l_last_sync_lsn, be64_to_cpu(rhead->h_lsn)); |
1216 | xlog_assign_grant_head(head: &log->l_reserve_head.grant, cycle: log->l_curr_cycle, |
1217 | space: BBTOB(log->l_curr_block)); |
1218 | xlog_assign_grant_head(head: &log->l_write_head.grant, cycle: log->l_curr_cycle, |
1219 | space: BBTOB(log->l_curr_block)); |
1220 | } |
1221 | |
1222 | /* |
1223 | * Find the sync block number or the tail of the log. |
1224 | * |
1225 | * This will be the block number of the last record to have its |
1226 | * associated buffers synced to disk. Every log record header has |
1227 | * a sync lsn embedded in it. LSNs hold block numbers, so it is easy |
1228 | * to get a sync block number. The only concern is to figure out which |
1229 | * log record header to believe. |
1230 | * |
1231 | * The following algorithm uses the log record header with the largest |
1232 | * lsn. The entire log record does not need to be valid. We only care |
1233 | * that the header is valid. |
1234 | * |
1235 | * We could speed up search by using current head_blk buffer, but it is not |
1236 | * available. |
1237 | */ |
1238 | STATIC int |
1239 | xlog_find_tail( |
1240 | struct xlog *log, |
1241 | xfs_daddr_t *head_blk, |
1242 | xfs_daddr_t *tail_blk) |
1243 | { |
1244 | xlog_rec_header_t *rhead; |
1245 | char *offset = NULL; |
1246 | char *buffer; |
1247 | int error; |
1248 | xfs_daddr_t rhead_blk; |
1249 | xfs_lsn_t tail_lsn; |
1250 | bool wrapped = false; |
1251 | bool clean = false; |
1252 | |
1253 | /* |
1254 | * Find previous log record |
1255 | */ |
1256 | if ((error = xlog_find_head(log, return_head_blk: head_blk))) |
1257 | return error; |
1258 | ASSERT(*head_blk < INT_MAX); |
1259 | |
1260 | buffer = xlog_alloc_buffer(log, nbblks: 1); |
1261 | if (!buffer) |
1262 | return -ENOMEM; |
1263 | if (*head_blk == 0) { /* special case */ |
1264 | error = xlog_bread(log, blk_no: 0, nbblks: 1, data: buffer, offset: &offset); |
1265 | if (error) |
1266 | goto done; |
1267 | |
1268 | if (xlog_get_cycle(offset) == 0) { |
1269 | *tail_blk = 0; |
1270 | /* leave all other log inited values alone */ |
1271 | goto done; |
1272 | } |
1273 | } |
1274 | |
1275 | /* |
1276 | * Search backwards through the log looking for the log record header |
1277 | * block. This wraps all the way back around to the head so something is |
1278 | * seriously wrong if we can't find it. |
1279 | */ |
1280 | error = xlog_rseek_logrec_hdr(log, *head_blk, *head_blk, 1, buffer, |
1281 | &rhead_blk, &rhead, &wrapped); |
1282 | if (error < 0) |
1283 | goto done; |
1284 | if (!error) { |
1285 | xfs_warn(log->l_mp, "%s: couldn't find sync record" , __func__); |
1286 | error = -EFSCORRUPTED; |
1287 | goto done; |
1288 | } |
1289 | *tail_blk = BLOCK_LSN(be64_to_cpu(rhead->h_tail_lsn)); |
1290 | |
1291 | /* |
1292 | * Set the log state based on the current head record. |
1293 | */ |
1294 | xlog_set_state(log, *head_blk, rhead, rhead_blk, wrapped); |
1295 | tail_lsn = atomic64_read(&log->l_tail_lsn); |
1296 | |
1297 | /* |
1298 | * Look for an unmount record at the head of the log. This sets the log |
1299 | * state to determine whether recovery is necessary. |
1300 | */ |
1301 | error = xlog_check_unmount_rec(log, head_blk, tail_blk, rhead, |
1302 | rhead_blk, buffer, &clean); |
1303 | if (error) |
1304 | goto done; |
1305 | |
1306 | /* |
1307 | * Verify the log head if the log is not clean (e.g., we have anything |
1308 | * but an unmount record at the head). This uses CRC verification to |
1309 | * detect and trim torn writes. If discovered, CRC failures are |
1310 | * considered torn writes and the log head is trimmed accordingly. |
1311 | * |
1312 | * Note that we can only run CRC verification when the log is dirty |
1313 | * because there's no guarantee that the log data behind an unmount |
1314 | * record is compatible with the current architecture. |
1315 | */ |
1316 | if (!clean) { |
1317 | xfs_daddr_t orig_head = *head_blk; |
1318 | |
1319 | error = xlog_verify_head(log, head_blk, tail_blk, buffer, |
1320 | &rhead_blk, &rhead, &wrapped); |
1321 | if (error) |
1322 | goto done; |
1323 | |
1324 | /* update in-core state again if the head changed */ |
1325 | if (*head_blk != orig_head) { |
1326 | xlog_set_state(log, *head_blk, rhead, rhead_blk, |
1327 | wrapped); |
1328 | tail_lsn = atomic64_read(&log->l_tail_lsn); |
1329 | error = xlog_check_unmount_rec(log, head_blk, tail_blk, |
1330 | rhead, rhead_blk, buffer, |
1331 | &clean); |
1332 | if (error) |
1333 | goto done; |
1334 | } |
1335 | } |
1336 | |
1337 | /* |
1338 | * Note that the unmount was clean. If the unmount was not clean, we |
1339 | * need to know this to rebuild the superblock counters from the perag |
1340 | * headers if we have a filesystem using non-persistent counters. |
1341 | */ |
1342 | if (clean) |
1343 | set_bit(XFS_OPSTATE_CLEAN, addr: &log->l_mp->m_opstate); |
1344 | |
1345 | /* |
1346 | * Make sure that there are no blocks in front of the head |
1347 | * with the same cycle number as the head. This can happen |
1348 | * because we allow multiple outstanding log writes concurrently, |
1349 | * and the later writes might make it out before earlier ones. |
1350 | * |
1351 | * We use the lsn from before modifying it so that we'll never |
1352 | * overwrite the unmount record after a clean unmount. |
1353 | * |
1354 | * Do this only if we are going to recover the filesystem |
1355 | * |
1356 | * NOTE: This used to say "if (!readonly)" |
1357 | * However on Linux, we can & do recover a read-only filesystem. |
1358 | * We only skip recovery if NORECOVERY is specified on mount, |
1359 | * in which case we would not be here. |
1360 | * |
1361 | * But... if the -device- itself is readonly, just skip this. |
1362 | * We can't recover this device anyway, so it won't matter. |
1363 | */ |
1364 | if (!xfs_readonly_buftarg(log->l_targ)) |
1365 | error = xlog_clear_stale_blocks(log, tail_lsn); |
1366 | |
1367 | done: |
1368 | kmem_free(ptr: buffer); |
1369 | |
1370 | if (error) |
1371 | xfs_warn(log->l_mp, "failed to locate log tail" ); |
1372 | return error; |
1373 | } |
1374 | |
1375 | /* |
1376 | * Is the log zeroed at all? |
1377 | * |
1378 | * The last binary search should be changed to perform an X block read |
1379 | * once X becomes small enough. You can then search linearly through |
1380 | * the X blocks. This will cut down on the number of reads we need to do. |
1381 | * |
1382 | * If the log is partially zeroed, this routine will pass back the blkno |
1383 | * of the first block with cycle number 0. It won't have a complete LR |
1384 | * preceding it. |
1385 | * |
1386 | * Return: |
1387 | * 0 => the log is completely written to |
1388 | * 1 => use *blk_no as the first block of the log |
1389 | * <0 => error has occurred |
1390 | */ |
1391 | STATIC int |
1392 | xlog_find_zeroed( |
1393 | struct xlog *log, |
1394 | xfs_daddr_t *blk_no) |
1395 | { |
1396 | char *buffer; |
1397 | char *offset; |
1398 | uint first_cycle, last_cycle; |
1399 | xfs_daddr_t new_blk, last_blk, start_blk; |
1400 | xfs_daddr_t num_scan_bblks; |
1401 | int error, log_bbnum = log->l_logBBsize; |
1402 | |
1403 | *blk_no = 0; |
1404 | |
1405 | /* check totally zeroed log */ |
1406 | buffer = xlog_alloc_buffer(log, nbblks: 1); |
1407 | if (!buffer) |
1408 | return -ENOMEM; |
1409 | error = xlog_bread(log, blk_no: 0, nbblks: 1, data: buffer, offset: &offset); |
1410 | if (error) |
1411 | goto out_free_buffer; |
1412 | |
1413 | first_cycle = xlog_get_cycle(offset); |
1414 | if (first_cycle == 0) { /* completely zeroed log */ |
1415 | *blk_no = 0; |
1416 | kmem_free(ptr: buffer); |
1417 | return 1; |
1418 | } |
1419 | |
1420 | /* check partially zeroed log */ |
1421 | error = xlog_bread(log, blk_no: log_bbnum-1, nbblks: 1, data: buffer, offset: &offset); |
1422 | if (error) |
1423 | goto out_free_buffer; |
1424 | |
1425 | last_cycle = xlog_get_cycle(offset); |
1426 | if (last_cycle != 0) { /* log completely written to */ |
1427 | kmem_free(ptr: buffer); |
1428 | return 0; |
1429 | } |
1430 | |
1431 | /* we have a partially zeroed log */ |
1432 | last_blk = log_bbnum-1; |
1433 | error = xlog_find_cycle_start(log, buffer, first_blk: 0, last_blk: &last_blk, cycle: 0); |
1434 | if (error) |
1435 | goto out_free_buffer; |
1436 | |
1437 | /* |
1438 | * Validate the answer. Because there is no way to guarantee that |
1439 | * the entire log is made up of log records which are the same size, |
1440 | * we scan over the defined maximum blocks. At this point, the maximum |
1441 | * is not chosen to mean anything special. XXXmiken |
1442 | */ |
1443 | num_scan_bblks = XLOG_TOTAL_REC_SHIFT(log); |
1444 | ASSERT(num_scan_bblks <= INT_MAX); |
1445 | |
1446 | if (last_blk < num_scan_bblks) |
1447 | num_scan_bblks = last_blk; |
1448 | start_blk = last_blk - num_scan_bblks; |
1449 | |
1450 | /* |
1451 | * We search for any instances of cycle number 0 that occur before |
1452 | * our current estimate of the head. What we're trying to detect is |
1453 | * 1 ... | 0 | 1 | 0... |
1454 | * ^ binary search ends here |
1455 | */ |
1456 | if ((error = xlog_find_verify_cycle(log, start_blk, |
1457 | nbblks: (int)num_scan_bblks, stop_on_cycle_no: 0, new_blk: &new_blk))) |
1458 | goto out_free_buffer; |
1459 | if (new_blk != -1) |
1460 | last_blk = new_blk; |
1461 | |
1462 | /* |
1463 | * Potentially backup over partial log record write. We don't need |
1464 | * to search the end of the log because we know it is zero. |
1465 | */ |
1466 | error = xlog_find_verify_log_record(log, start_blk, last_blk: &last_blk, extra_bblks: 0); |
1467 | if (error == 1) |
1468 | error = -EIO; |
1469 | if (error) |
1470 | goto out_free_buffer; |
1471 | |
1472 | *blk_no = last_blk; |
1473 | out_free_buffer: |
1474 | kmem_free(ptr: buffer); |
1475 | if (error) |
1476 | return error; |
1477 | return 1; |
1478 | } |
1479 | |
1480 | /* |
1481 | * These are simple subroutines used by xlog_clear_stale_blocks() below |
1482 | * to initialize a buffer full of empty log record headers and write |
1483 | * them into the log. |
1484 | */ |
1485 | STATIC void |
1486 | xlog_add_record( |
1487 | struct xlog *log, |
1488 | char *buf, |
1489 | int cycle, |
1490 | int block, |
1491 | int tail_cycle, |
1492 | int tail_block) |
1493 | { |
1494 | xlog_rec_header_t *recp = (xlog_rec_header_t *)buf; |
1495 | |
1496 | memset(buf, 0, BBSIZE); |
1497 | recp->h_magicno = cpu_to_be32(XLOG_HEADER_MAGIC_NUM); |
1498 | recp->h_cycle = cpu_to_be32(cycle); |
1499 | recp->h_version = cpu_to_be32( |
1500 | xfs_has_logv2(log->l_mp) ? 2 : 1); |
1501 | recp->h_lsn = cpu_to_be64(xlog_assign_lsn(cycle, block)); |
1502 | recp->h_tail_lsn = cpu_to_be64(xlog_assign_lsn(tail_cycle, tail_block)); |
1503 | recp->h_fmt = cpu_to_be32(XLOG_FMT); |
1504 | memcpy(&recp->h_fs_uuid, &log->l_mp->m_sb.sb_uuid, sizeof(uuid_t)); |
1505 | } |
1506 | |
1507 | STATIC int |
1508 | xlog_write_log_records( |
1509 | struct xlog *log, |
1510 | int cycle, |
1511 | int start_block, |
1512 | int blocks, |
1513 | int tail_cycle, |
1514 | int tail_block) |
1515 | { |
1516 | char *offset; |
1517 | char *buffer; |
1518 | int balign, ealign; |
1519 | int sectbb = log->l_sectBBsize; |
1520 | int end_block = start_block + blocks; |
1521 | int bufblks; |
1522 | int error = 0; |
1523 | int i, j = 0; |
1524 | |
1525 | /* |
1526 | * Greedily allocate a buffer big enough to handle the full |
1527 | * range of basic blocks to be written. If that fails, try |
1528 | * a smaller size. We need to be able to write at least a |
1529 | * log sector, or we're out of luck. |
1530 | */ |
1531 | bufblks = roundup_pow_of_two(blocks); |
1532 | while (bufblks > log->l_logBBsize) |
1533 | bufblks >>= 1; |
1534 | while (!(buffer = xlog_alloc_buffer(log, nbblks: bufblks))) { |
1535 | bufblks >>= 1; |
1536 | if (bufblks < sectbb) |
1537 | return -ENOMEM; |
1538 | } |
1539 | |
1540 | /* We may need to do a read at the start to fill in part of |
1541 | * the buffer in the starting sector not covered by the first |
1542 | * write below. |
1543 | */ |
1544 | balign = round_down(start_block, sectbb); |
1545 | if (balign != start_block) { |
1546 | error = xlog_bread_noalign(log, blk_no: start_block, nbblks: 1, data: buffer); |
1547 | if (error) |
1548 | goto out_free_buffer; |
1549 | |
1550 | j = start_block - balign; |
1551 | } |
1552 | |
1553 | for (i = start_block; i < end_block; i += bufblks) { |
1554 | int bcount, endcount; |
1555 | |
1556 | bcount = min(bufblks, end_block - start_block); |
1557 | endcount = bcount - j; |
1558 | |
1559 | /* We may need to do a read at the end to fill in part of |
1560 | * the buffer in the final sector not covered by the write. |
1561 | * If this is the same sector as the above read, skip it. |
1562 | */ |
1563 | ealign = round_down(end_block, sectbb); |
1564 | if (j == 0 && (start_block + endcount > ealign)) { |
1565 | error = xlog_bread_noalign(log, blk_no: ealign, nbblks: sectbb, |
1566 | data: buffer + BBTOB(ealign - start_block)); |
1567 | if (error) |
1568 | break; |
1569 | |
1570 | } |
1571 | |
1572 | offset = buffer + xlog_align(log, blk_no: start_block); |
1573 | for (; j < endcount; j++) { |
1574 | xlog_add_record(log, buf: offset, cycle, block: i+j, |
1575 | tail_cycle, tail_block); |
1576 | offset += BBSIZE; |
1577 | } |
1578 | error = xlog_bwrite(log, blk_no: start_block, nbblks: endcount, data: buffer); |
1579 | if (error) |
1580 | break; |
1581 | start_block += endcount; |
1582 | j = 0; |
1583 | } |
1584 | |
1585 | out_free_buffer: |
1586 | kmem_free(ptr: buffer); |
1587 | return error; |
1588 | } |
1589 | |
1590 | /* |
1591 | * This routine is called to blow away any incomplete log writes out |
1592 | * in front of the log head. We do this so that we won't become confused |
1593 | * if we come up, write only a little bit more, and then crash again. |
1594 | * If we leave the partial log records out there, this situation could |
1595 | * cause us to think those partial writes are valid blocks since they |
1596 | * have the current cycle number. We get rid of them by overwriting them |
1597 | * with empty log records with the old cycle number rather than the |
1598 | * current one. |
1599 | * |
1600 | * The tail lsn is passed in rather than taken from |
1601 | * the log so that we will not write over the unmount record after a |
1602 | * clean unmount in a 512 block log. Doing so would leave the log without |
1603 | * any valid log records in it until a new one was written. If we crashed |
1604 | * during that time we would not be able to recover. |
1605 | */ |
1606 | STATIC int |
1607 | xlog_clear_stale_blocks( |
1608 | struct xlog *log, |
1609 | xfs_lsn_t tail_lsn) |
1610 | { |
1611 | int tail_cycle, head_cycle; |
1612 | int tail_block, head_block; |
1613 | int tail_distance, max_distance; |
1614 | int distance; |
1615 | int error; |
1616 | |
1617 | tail_cycle = CYCLE_LSN(tail_lsn); |
1618 | tail_block = BLOCK_LSN(tail_lsn); |
1619 | head_cycle = log->l_curr_cycle; |
1620 | head_block = log->l_curr_block; |
1621 | |
1622 | /* |
1623 | * Figure out the distance between the new head of the log |
1624 | * and the tail. We want to write over any blocks beyond the |
1625 | * head that we may have written just before the crash, but |
1626 | * we don't want to overwrite the tail of the log. |
1627 | */ |
1628 | if (head_cycle == tail_cycle) { |
1629 | /* |
1630 | * The tail is behind the head in the physical log, |
1631 | * so the distance from the head to the tail is the |
1632 | * distance from the head to the end of the log plus |
1633 | * the distance from the beginning of the log to the |
1634 | * tail. |
1635 | */ |
1636 | if (XFS_IS_CORRUPT(log->l_mp, |
1637 | head_block < tail_block || |
1638 | head_block >= log->l_logBBsize)) |
1639 | return -EFSCORRUPTED; |
1640 | tail_distance = tail_block + (log->l_logBBsize - head_block); |
1641 | } else { |
1642 | /* |
1643 | * The head is behind the tail in the physical log, |
1644 | * so the distance from the head to the tail is just |
1645 | * the tail block minus the head block. |
1646 | */ |
1647 | if (XFS_IS_CORRUPT(log->l_mp, |
1648 | head_block >= tail_block || |
1649 | head_cycle != tail_cycle + 1)) |
1650 | return -EFSCORRUPTED; |
1651 | tail_distance = tail_block - head_block; |
1652 | } |
1653 | |
1654 | /* |
1655 | * If the head is right up against the tail, we can't clear |
1656 | * anything. |
1657 | */ |
1658 | if (tail_distance <= 0) { |
1659 | ASSERT(tail_distance == 0); |
1660 | return 0; |
1661 | } |
1662 | |
1663 | max_distance = XLOG_TOTAL_REC_SHIFT(log); |
1664 | /* |
1665 | * Take the smaller of the maximum amount of outstanding I/O |
1666 | * we could have and the distance to the tail to clear out. |
1667 | * We take the smaller so that we don't overwrite the tail and |
1668 | * we don't waste all day writing from the head to the tail |
1669 | * for no reason. |
1670 | */ |
1671 | max_distance = min(max_distance, tail_distance); |
1672 | |
1673 | if ((head_block + max_distance) <= log->l_logBBsize) { |
1674 | /* |
1675 | * We can stomp all the blocks we need to without |
1676 | * wrapping around the end of the log. Just do it |
1677 | * in a single write. Use the cycle number of the |
1678 | * current cycle minus one so that the log will look like: |
1679 | * n ... | n - 1 ... |
1680 | */ |
1681 | error = xlog_write_log_records(log, cycle: (head_cycle - 1), |
1682 | start_block: head_block, blocks: max_distance, tail_cycle, |
1683 | tail_block); |
1684 | if (error) |
1685 | return error; |
1686 | } else { |
1687 | /* |
1688 | * We need to wrap around the end of the physical log in |
1689 | * order to clear all the blocks. Do it in two separate |
1690 | * I/Os. The first write should be from the head to the |
1691 | * end of the physical log, and it should use the current |
1692 | * cycle number minus one just like above. |
1693 | */ |
1694 | distance = log->l_logBBsize - head_block; |
1695 | error = xlog_write_log_records(log, cycle: (head_cycle - 1), |
1696 | start_block: head_block, blocks: distance, tail_cycle, |
1697 | tail_block); |
1698 | |
1699 | if (error) |
1700 | return error; |
1701 | |
1702 | /* |
1703 | * Now write the blocks at the start of the physical log. |
1704 | * This writes the remainder of the blocks we want to clear. |
1705 | * It uses the current cycle number since we're now on the |
1706 | * same cycle as the head so that we get: |
1707 | * n ... n ... | n - 1 ... |
1708 | * ^^^^^ blocks we're writing |
1709 | */ |
1710 | distance = max_distance - (log->l_logBBsize - head_block); |
1711 | error = xlog_write_log_records(log, cycle: head_cycle, start_block: 0, blocks: distance, |
1712 | tail_cycle, tail_block); |
1713 | if (error) |
1714 | return error; |
1715 | } |
1716 | |
1717 | return 0; |
1718 | } |
1719 | |
1720 | /* |
1721 | * Release the recovered intent item in the AIL that matches the given intent |
1722 | * type and intent id. |
1723 | */ |
1724 | void |
1725 | xlog_recover_release_intent( |
1726 | struct xlog *log, |
1727 | unsigned short intent_type, |
1728 | uint64_t intent_id) |
1729 | { |
1730 | struct xfs_ail_cursor cur; |
1731 | struct xfs_log_item *lip; |
1732 | struct xfs_ail *ailp = log->l_ailp; |
1733 | |
1734 | spin_lock(lock: &ailp->ail_lock); |
1735 | for (lip = xfs_trans_ail_cursor_first(ailp, &cur, 0); lip != NULL; |
1736 | lip = xfs_trans_ail_cursor_next(ailp, cur: &cur)) { |
1737 | if (lip->li_type != intent_type) |
1738 | continue; |
1739 | if (!lip->li_ops->iop_match(lip, intent_id)) |
1740 | continue; |
1741 | |
1742 | spin_unlock(lock: &ailp->ail_lock); |
1743 | lip->li_ops->iop_release(lip); |
1744 | spin_lock(lock: &ailp->ail_lock); |
1745 | break; |
1746 | } |
1747 | |
1748 | xfs_trans_ail_cursor_done(cur: &cur); |
1749 | spin_unlock(lock: &ailp->ail_lock); |
1750 | } |
1751 | |
1752 | int |
1753 | xlog_recover_iget( |
1754 | struct xfs_mount *mp, |
1755 | xfs_ino_t ino, |
1756 | struct xfs_inode **ipp) |
1757 | { |
1758 | int error; |
1759 | |
1760 | error = xfs_iget(mp, NULL, ino, flags: 0, lock_flags: 0, ipp); |
1761 | if (error) |
1762 | return error; |
1763 | |
1764 | error = xfs_qm_dqattach(*ipp); |
1765 | if (error) { |
1766 | xfs_irele(ip: *ipp); |
1767 | return error; |
1768 | } |
1769 | |
1770 | if (VFS_I(ip: *ipp)->i_nlink == 0) |
1771 | xfs_iflags_set(ip: *ipp, XFS_IRECOVERY); |
1772 | |
1773 | return 0; |
1774 | } |
1775 | |
1776 | /****************************************************************************** |
1777 | * |
1778 | * Log recover routines |
1779 | * |
1780 | ****************************************************************************** |
1781 | */ |
1782 | static const struct xlog_recover_item_ops *xlog_recover_item_ops[] = { |
1783 | &xlog_buf_item_ops, |
1784 | &xlog_inode_item_ops, |
1785 | &xlog_dquot_item_ops, |
1786 | &xlog_quotaoff_item_ops, |
1787 | &xlog_icreate_item_ops, |
1788 | &xlog_efi_item_ops, |
1789 | &xlog_efd_item_ops, |
1790 | &xlog_rui_item_ops, |
1791 | &xlog_rud_item_ops, |
1792 | &xlog_cui_item_ops, |
1793 | &xlog_cud_item_ops, |
1794 | &xlog_bui_item_ops, |
1795 | &xlog_bud_item_ops, |
1796 | &xlog_attri_item_ops, |
1797 | &xlog_attrd_item_ops, |
1798 | }; |
1799 | |
1800 | static const struct xlog_recover_item_ops * |
1801 | xlog_find_item_ops( |
1802 | struct xlog_recover_item *item) |
1803 | { |
1804 | unsigned int i; |
1805 | |
1806 | for (i = 0; i < ARRAY_SIZE(xlog_recover_item_ops); i++) |
1807 | if (ITEM_TYPE(item) == xlog_recover_item_ops[i]->item_type) |
1808 | return xlog_recover_item_ops[i]; |
1809 | |
1810 | return NULL; |
1811 | } |
1812 | |
1813 | /* |
1814 | * Sort the log items in the transaction. |
1815 | * |
1816 | * The ordering constraints are defined by the inode allocation and unlink |
1817 | * behaviour. The rules are: |
1818 | * |
1819 | * 1. Every item is only logged once in a given transaction. Hence it |
1820 | * represents the last logged state of the item. Hence ordering is |
1821 | * dependent on the order in which operations need to be performed so |
1822 | * required initial conditions are always met. |
1823 | * |
1824 | * 2. Cancelled buffers are recorded in pass 1 in a separate table and |
1825 | * there's nothing to replay from them so we can simply cull them |
1826 | * from the transaction. However, we can't do that until after we've |
1827 | * replayed all the other items because they may be dependent on the |
1828 | * cancelled buffer and replaying the cancelled buffer can remove it |
1829 | * form the cancelled buffer table. Hence they have tobe done last. |
1830 | * |
1831 | * 3. Inode allocation buffers must be replayed before inode items that |
1832 | * read the buffer and replay changes into it. For filesystems using the |
1833 | * ICREATE transactions, this means XFS_LI_ICREATE objects need to get |
1834 | * treated the same as inode allocation buffers as they create and |
1835 | * initialise the buffers directly. |
1836 | * |
1837 | * 4. Inode unlink buffers must be replayed after inode items are replayed. |
1838 | * This ensures that inodes are completely flushed to the inode buffer |
1839 | * in a "free" state before we remove the unlinked inode list pointer. |
1840 | * |
1841 | * Hence the ordering needs to be inode allocation buffers first, inode items |
1842 | * second, inode unlink buffers third and cancelled buffers last. |
1843 | * |
1844 | * But there's a problem with that - we can't tell an inode allocation buffer |
1845 | * apart from a regular buffer, so we can't separate them. We can, however, |
1846 | * tell an inode unlink buffer from the others, and so we can separate them out |
1847 | * from all the other buffers and move them to last. |
1848 | * |
1849 | * Hence, 4 lists, in order from head to tail: |
1850 | * - buffer_list for all buffers except cancelled/inode unlink buffers |
1851 | * - item_list for all non-buffer items |
1852 | * - inode_buffer_list for inode unlink buffers |
1853 | * - cancel_list for the cancelled buffers |
1854 | * |
1855 | * Note that we add objects to the tail of the lists so that first-to-last |
1856 | * ordering is preserved within the lists. Adding objects to the head of the |
1857 | * list means when we traverse from the head we walk them in last-to-first |
1858 | * order. For cancelled buffers and inode unlink buffers this doesn't matter, |
1859 | * but for all other items there may be specific ordering that we need to |
1860 | * preserve. |
1861 | */ |
1862 | STATIC int |
1863 | xlog_recover_reorder_trans( |
1864 | struct xlog *log, |
1865 | struct xlog_recover *trans, |
1866 | int pass) |
1867 | { |
1868 | struct xlog_recover_item *item, *n; |
1869 | int error = 0; |
1870 | LIST_HEAD(sort_list); |
1871 | LIST_HEAD(cancel_list); |
1872 | LIST_HEAD(buffer_list); |
1873 | LIST_HEAD(inode_buffer_list); |
1874 | LIST_HEAD(item_list); |
1875 | |
1876 | list_splice_init(list: &trans->r_itemq, head: &sort_list); |
1877 | list_for_each_entry_safe(item, n, &sort_list, ri_list) { |
1878 | enum xlog_recover_reorder fate = XLOG_REORDER_ITEM_LIST; |
1879 | |
1880 | item->ri_ops = xlog_find_item_ops(item); |
1881 | if (!item->ri_ops) { |
1882 | xfs_warn(log->l_mp, |
1883 | "%s: unrecognized type of log operation (%d)" , |
1884 | __func__, ITEM_TYPE(item)); |
1885 | ASSERT(0); |
1886 | /* |
1887 | * return the remaining items back to the transaction |
1888 | * item list so they can be freed in caller. |
1889 | */ |
1890 | if (!list_empty(head: &sort_list)) |
1891 | list_splice_init(list: &sort_list, head: &trans->r_itemq); |
1892 | error = -EFSCORRUPTED; |
1893 | break; |
1894 | } |
1895 | |
1896 | if (item->ri_ops->reorder) |
1897 | fate = item->ri_ops->reorder(item); |
1898 | |
1899 | switch (fate) { |
1900 | case XLOG_REORDER_BUFFER_LIST: |
1901 | list_move_tail(list: &item->ri_list, head: &buffer_list); |
1902 | break; |
1903 | case XLOG_REORDER_CANCEL_LIST: |
1904 | trace_xfs_log_recover_item_reorder_head(log, |
1905 | trans, item, pass); |
1906 | list_move(list: &item->ri_list, head: &cancel_list); |
1907 | break; |
1908 | case XLOG_REORDER_INODE_BUFFER_LIST: |
1909 | list_move(list: &item->ri_list, head: &inode_buffer_list); |
1910 | break; |
1911 | case XLOG_REORDER_ITEM_LIST: |
1912 | trace_xfs_log_recover_item_reorder_tail(log, |
1913 | trans, item, pass); |
1914 | list_move_tail(list: &item->ri_list, head: &item_list); |
1915 | break; |
1916 | } |
1917 | } |
1918 | |
1919 | ASSERT(list_empty(&sort_list)); |
1920 | if (!list_empty(head: &buffer_list)) |
1921 | list_splice(list: &buffer_list, head: &trans->r_itemq); |
1922 | if (!list_empty(head: &item_list)) |
1923 | list_splice_tail(list: &item_list, head: &trans->r_itemq); |
1924 | if (!list_empty(head: &inode_buffer_list)) |
1925 | list_splice_tail(list: &inode_buffer_list, head: &trans->r_itemq); |
1926 | if (!list_empty(head: &cancel_list)) |
1927 | list_splice_tail(list: &cancel_list, head: &trans->r_itemq); |
1928 | return error; |
1929 | } |
1930 | |
1931 | void |
1932 | xlog_buf_readahead( |
1933 | struct xlog *log, |
1934 | xfs_daddr_t blkno, |
1935 | uint len, |
1936 | const struct xfs_buf_ops *ops) |
1937 | { |
1938 | if (!xlog_is_buffer_cancelled(log, blkno, len)) |
1939 | xfs_buf_readahead(target: log->l_mp->m_ddev_targp, blkno, numblks: len, ops); |
1940 | } |
1941 | |
1942 | STATIC int |
1943 | xlog_recover_items_pass2( |
1944 | struct xlog *log, |
1945 | struct xlog_recover *trans, |
1946 | struct list_head *buffer_list, |
1947 | struct list_head *item_list) |
1948 | { |
1949 | struct xlog_recover_item *item; |
1950 | int error = 0; |
1951 | |
1952 | list_for_each_entry(item, item_list, ri_list) { |
1953 | trace_xfs_log_recover_item_recover(log, trans, item, |
1954 | XLOG_RECOVER_PASS2); |
1955 | |
1956 | if (item->ri_ops->commit_pass2) |
1957 | error = item->ri_ops->commit_pass2(log, buffer_list, |
1958 | item, trans->r_lsn); |
1959 | if (error) |
1960 | return error; |
1961 | } |
1962 | |
1963 | return error; |
1964 | } |
1965 | |
1966 | /* |
1967 | * Perform the transaction. |
1968 | * |
1969 | * If the transaction modifies a buffer or inode, do it now. Otherwise, |
1970 | * EFIs and EFDs get queued up by adding entries into the AIL for them. |
1971 | */ |
1972 | STATIC int |
1973 | xlog_recover_commit_trans( |
1974 | struct xlog *log, |
1975 | struct xlog_recover *trans, |
1976 | int pass, |
1977 | struct list_head *buffer_list) |
1978 | { |
1979 | int error = 0; |
1980 | int items_queued = 0; |
1981 | struct xlog_recover_item *item; |
1982 | struct xlog_recover_item *next; |
1983 | LIST_HEAD (ra_list); |
1984 | LIST_HEAD (done_list); |
1985 | |
1986 | #define XLOG_RECOVER_COMMIT_QUEUE_MAX 100 |
1987 | |
1988 | hlist_del_init(n: &trans->r_list); |
1989 | |
1990 | error = xlog_recover_reorder_trans(log, trans, pass); |
1991 | if (error) |
1992 | return error; |
1993 | |
1994 | list_for_each_entry_safe(item, next, &trans->r_itemq, ri_list) { |
1995 | trace_xfs_log_recover_item_recover(log, trans, item, pass); |
1996 | |
1997 | switch (pass) { |
1998 | case XLOG_RECOVER_PASS1: |
1999 | if (item->ri_ops->commit_pass1) |
2000 | error = item->ri_ops->commit_pass1(log, item); |
2001 | break; |
2002 | case XLOG_RECOVER_PASS2: |
2003 | if (item->ri_ops->ra_pass2) |
2004 | item->ri_ops->ra_pass2(log, item); |
2005 | list_move_tail(list: &item->ri_list, head: &ra_list); |
2006 | items_queued++; |
2007 | if (items_queued >= XLOG_RECOVER_COMMIT_QUEUE_MAX) { |
2008 | error = xlog_recover_items_pass2(log, trans, |
2009 | buffer_list, item_list: &ra_list); |
2010 | list_splice_tail_init(list: &ra_list, head: &done_list); |
2011 | items_queued = 0; |
2012 | } |
2013 | |
2014 | break; |
2015 | default: |
2016 | ASSERT(0); |
2017 | } |
2018 | |
2019 | if (error) |
2020 | goto out; |
2021 | } |
2022 | |
2023 | out: |
2024 | if (!list_empty(head: &ra_list)) { |
2025 | if (!error) |
2026 | error = xlog_recover_items_pass2(log, trans, |
2027 | buffer_list, item_list: &ra_list); |
2028 | list_splice_tail_init(list: &ra_list, head: &done_list); |
2029 | } |
2030 | |
2031 | if (!list_empty(head: &done_list)) |
2032 | list_splice_init(list: &done_list, head: &trans->r_itemq); |
2033 | |
2034 | return error; |
2035 | } |
2036 | |
2037 | STATIC void |
2038 | xlog_recover_add_item( |
2039 | struct list_head *head) |
2040 | { |
2041 | struct xlog_recover_item *item; |
2042 | |
2043 | item = kmem_zalloc(sizeof(struct xlog_recover_item), 0); |
2044 | INIT_LIST_HEAD(list: &item->ri_list); |
2045 | list_add_tail(new: &item->ri_list, head); |
2046 | } |
2047 | |
2048 | STATIC int |
2049 | xlog_recover_add_to_cont_trans( |
2050 | struct xlog *log, |
2051 | struct xlog_recover *trans, |
2052 | char *dp, |
2053 | int len) |
2054 | { |
2055 | struct xlog_recover_item *item; |
2056 | char *ptr, *old_ptr; |
2057 | int old_len; |
2058 | |
2059 | /* |
2060 | * If the transaction is empty, the header was split across this and the |
2061 | * previous record. Copy the rest of the header. |
2062 | */ |
2063 | if (list_empty(head: &trans->r_itemq)) { |
2064 | ASSERT(len <= sizeof(struct xfs_trans_header)); |
2065 | if (len > sizeof(struct xfs_trans_header)) { |
2066 | xfs_warn(log->l_mp, "%s: bad header length" , __func__); |
2067 | return -EFSCORRUPTED; |
2068 | } |
2069 | |
2070 | xlog_recover_add_item(head: &trans->r_itemq); |
2071 | ptr = (char *)&trans->r_theader + |
2072 | sizeof(struct xfs_trans_header) - len; |
2073 | memcpy(ptr, dp, len); |
2074 | return 0; |
2075 | } |
2076 | |
2077 | /* take the tail entry */ |
2078 | item = list_entry(trans->r_itemq.prev, struct xlog_recover_item, |
2079 | ri_list); |
2080 | |
2081 | old_ptr = item->ri_buf[item->ri_cnt-1].i_addr; |
2082 | old_len = item->ri_buf[item->ri_cnt-1].i_len; |
2083 | |
2084 | ptr = kvrealloc(p: old_ptr, oldsize: old_len, newsize: len + old_len, GFP_KERNEL); |
2085 | if (!ptr) |
2086 | return -ENOMEM; |
2087 | memcpy(&ptr[old_len], dp, len); |
2088 | item->ri_buf[item->ri_cnt-1].i_len += len; |
2089 | item->ri_buf[item->ri_cnt-1].i_addr = ptr; |
2090 | trace_xfs_log_recover_item_add_cont(log, trans, item, pass: 0); |
2091 | return 0; |
2092 | } |
2093 | |
2094 | /* |
2095 | * The next region to add is the start of a new region. It could be |
2096 | * a whole region or it could be the first part of a new region. Because |
2097 | * of this, the assumption here is that the type and size fields of all |
2098 | * format structures fit into the first 32 bits of the structure. |
2099 | * |
2100 | * This works because all regions must be 32 bit aligned. Therefore, we |
2101 | * either have both fields or we have neither field. In the case we have |
2102 | * neither field, the data part of the region is zero length. We only have |
2103 | * a log_op_header and can throw away the header since a new one will appear |
2104 | * later. If we have at least 4 bytes, then we can determine how many regions |
2105 | * will appear in the current log item. |
2106 | */ |
2107 | STATIC int |
2108 | xlog_recover_add_to_trans( |
2109 | struct xlog *log, |
2110 | struct xlog_recover *trans, |
2111 | char *dp, |
2112 | int len) |
2113 | { |
2114 | struct xfs_inode_log_format *in_f; /* any will do */ |
2115 | struct xlog_recover_item *item; |
2116 | char *ptr; |
2117 | |
2118 | if (!len) |
2119 | return 0; |
2120 | if (list_empty(head: &trans->r_itemq)) { |
2121 | /* we need to catch log corruptions here */ |
2122 | if (*(uint *)dp != XFS_TRANS_HEADER_MAGIC) { |
2123 | xfs_warn(log->l_mp, "%s: bad header magic number" , |
2124 | __func__); |
2125 | ASSERT(0); |
2126 | return -EFSCORRUPTED; |
2127 | } |
2128 | |
2129 | if (len > sizeof(struct xfs_trans_header)) { |
2130 | xfs_warn(log->l_mp, "%s: bad header length" , __func__); |
2131 | ASSERT(0); |
2132 | return -EFSCORRUPTED; |
2133 | } |
2134 | |
2135 | /* |
2136 | * The transaction header can be arbitrarily split across op |
2137 | * records. If we don't have the whole thing here, copy what we |
2138 | * do have and handle the rest in the next record. |
2139 | */ |
2140 | if (len == sizeof(struct xfs_trans_header)) |
2141 | xlog_recover_add_item(head: &trans->r_itemq); |
2142 | memcpy(&trans->r_theader, dp, len); |
2143 | return 0; |
2144 | } |
2145 | |
2146 | ptr = kmem_alloc(len, 0); |
2147 | memcpy(ptr, dp, len); |
2148 | in_f = (struct xfs_inode_log_format *)ptr; |
2149 | |
2150 | /* take the tail entry */ |
2151 | item = list_entry(trans->r_itemq.prev, struct xlog_recover_item, |
2152 | ri_list); |
2153 | if (item->ri_total != 0 && |
2154 | item->ri_total == item->ri_cnt) { |
2155 | /* tail item is in use, get a new one */ |
2156 | xlog_recover_add_item(head: &trans->r_itemq); |
2157 | item = list_entry(trans->r_itemq.prev, |
2158 | struct xlog_recover_item, ri_list); |
2159 | } |
2160 | |
2161 | if (item->ri_total == 0) { /* first region to be added */ |
2162 | if (in_f->ilf_size == 0 || |
2163 | in_f->ilf_size > XLOG_MAX_REGIONS_IN_ITEM) { |
2164 | xfs_warn(log->l_mp, |
2165 | "bad number of regions (%d) in inode log format" , |
2166 | in_f->ilf_size); |
2167 | ASSERT(0); |
2168 | kmem_free(ptr); |
2169 | return -EFSCORRUPTED; |
2170 | } |
2171 | |
2172 | item->ri_total = in_f->ilf_size; |
2173 | item->ri_buf = |
2174 | kmem_zalloc(item->ri_total * sizeof(xfs_log_iovec_t), |
2175 | 0); |
2176 | } |
2177 | |
2178 | if (item->ri_total <= item->ri_cnt) { |
2179 | xfs_warn(log->l_mp, |
2180 | "log item region count (%d) overflowed size (%d)" , |
2181 | item->ri_cnt, item->ri_total); |
2182 | ASSERT(0); |
2183 | kmem_free(ptr); |
2184 | return -EFSCORRUPTED; |
2185 | } |
2186 | |
2187 | /* Description region is ri_buf[0] */ |
2188 | item->ri_buf[item->ri_cnt].i_addr = ptr; |
2189 | item->ri_buf[item->ri_cnt].i_len = len; |
2190 | item->ri_cnt++; |
2191 | trace_xfs_log_recover_item_add(log, trans, item, pass: 0); |
2192 | return 0; |
2193 | } |
2194 | |
2195 | /* |
2196 | * Free up any resources allocated by the transaction |
2197 | * |
2198 | * Remember that EFIs, EFDs, and IUNLINKs are handled later. |
2199 | */ |
2200 | STATIC void |
2201 | xlog_recover_free_trans( |
2202 | struct xlog_recover *trans) |
2203 | { |
2204 | struct xlog_recover_item *item, *n; |
2205 | int i; |
2206 | |
2207 | hlist_del_init(n: &trans->r_list); |
2208 | |
2209 | list_for_each_entry_safe(item, n, &trans->r_itemq, ri_list) { |
2210 | /* Free the regions in the item. */ |
2211 | list_del(entry: &item->ri_list); |
2212 | for (i = 0; i < item->ri_cnt; i++) |
2213 | kmem_free(ptr: item->ri_buf[i].i_addr); |
2214 | /* Free the item itself */ |
2215 | kmem_free(ptr: item->ri_buf); |
2216 | kmem_free(ptr: item); |
2217 | } |
2218 | /* Free the transaction recover structure */ |
2219 | kmem_free(ptr: trans); |
2220 | } |
2221 | |
2222 | /* |
2223 | * On error or completion, trans is freed. |
2224 | */ |
2225 | STATIC int |
2226 | xlog_recovery_process_trans( |
2227 | struct xlog *log, |
2228 | struct xlog_recover *trans, |
2229 | char *dp, |
2230 | unsigned int len, |
2231 | unsigned int flags, |
2232 | int pass, |
2233 | struct list_head *buffer_list) |
2234 | { |
2235 | int error = 0; |
2236 | bool freeit = false; |
2237 | |
2238 | /* mask off ophdr transaction container flags */ |
2239 | flags &= ~XLOG_END_TRANS; |
2240 | if (flags & XLOG_WAS_CONT_TRANS) |
2241 | flags &= ~XLOG_CONTINUE_TRANS; |
2242 | |
2243 | /* |
2244 | * Callees must not free the trans structure. We'll decide if we need to |
2245 | * free it or not based on the operation being done and it's result. |
2246 | */ |
2247 | switch (flags) { |
2248 | /* expected flag values */ |
2249 | case 0: |
2250 | case XLOG_CONTINUE_TRANS: |
2251 | error = xlog_recover_add_to_trans(log, trans, dp, len); |
2252 | break; |
2253 | case XLOG_WAS_CONT_TRANS: |
2254 | error = xlog_recover_add_to_cont_trans(log, trans, dp, len); |
2255 | break; |
2256 | case XLOG_COMMIT_TRANS: |
2257 | error = xlog_recover_commit_trans(log, trans, pass, |
2258 | buffer_list); |
2259 | /* success or fail, we are now done with this transaction. */ |
2260 | freeit = true; |
2261 | break; |
2262 | |
2263 | /* unexpected flag values */ |
2264 | case XLOG_UNMOUNT_TRANS: |
2265 | /* just skip trans */ |
2266 | xfs_warn(log->l_mp, "%s: Unmount LR" , __func__); |
2267 | freeit = true; |
2268 | break; |
2269 | case XLOG_START_TRANS: |
2270 | default: |
2271 | xfs_warn(log->l_mp, "%s: bad flag 0x%x" , __func__, flags); |
2272 | ASSERT(0); |
2273 | error = -EFSCORRUPTED; |
2274 | break; |
2275 | } |
2276 | if (error || freeit) |
2277 | xlog_recover_free_trans(trans); |
2278 | return error; |
2279 | } |
2280 | |
2281 | /* |
2282 | * Lookup the transaction recovery structure associated with the ID in the |
2283 | * current ophdr. If the transaction doesn't exist and the start flag is set in |
2284 | * the ophdr, then allocate a new transaction for future ID matches to find. |
2285 | * Either way, return what we found during the lookup - an existing transaction |
2286 | * or nothing. |
2287 | */ |
2288 | STATIC struct xlog_recover * |
2289 | xlog_recover_ophdr_to_trans( |
2290 | struct hlist_head rhash[], |
2291 | struct xlog_rec_header *rhead, |
2292 | struct xlog_op_header *ohead) |
2293 | { |
2294 | struct xlog_recover *trans; |
2295 | xlog_tid_t tid; |
2296 | struct hlist_head *rhp; |
2297 | |
2298 | tid = be32_to_cpu(ohead->oh_tid); |
2299 | rhp = &rhash[XLOG_RHASH(tid)]; |
2300 | hlist_for_each_entry(trans, rhp, r_list) { |
2301 | if (trans->r_log_tid == tid) |
2302 | return trans; |
2303 | } |
2304 | |
2305 | /* |
2306 | * skip over non-start transaction headers - we could be |
2307 | * processing slack space before the next transaction starts |
2308 | */ |
2309 | if (!(ohead->oh_flags & XLOG_START_TRANS)) |
2310 | return NULL; |
2311 | |
2312 | ASSERT(be32_to_cpu(ohead->oh_len) == 0); |
2313 | |
2314 | /* |
2315 | * This is a new transaction so allocate a new recovery container to |
2316 | * hold the recovery ops that will follow. |
2317 | */ |
2318 | trans = kmem_zalloc(sizeof(struct xlog_recover), 0); |
2319 | trans->r_log_tid = tid; |
2320 | trans->r_lsn = be64_to_cpu(rhead->h_lsn); |
2321 | INIT_LIST_HEAD(list: &trans->r_itemq); |
2322 | INIT_HLIST_NODE(h: &trans->r_list); |
2323 | hlist_add_head(n: &trans->r_list, h: rhp); |
2324 | |
2325 | /* |
2326 | * Nothing more to do for this ophdr. Items to be added to this new |
2327 | * transaction will be in subsequent ophdr containers. |
2328 | */ |
2329 | return NULL; |
2330 | } |
2331 | |
2332 | STATIC int |
2333 | xlog_recover_process_ophdr( |
2334 | struct xlog *log, |
2335 | struct hlist_head rhash[], |
2336 | struct xlog_rec_header *rhead, |
2337 | struct xlog_op_header *ohead, |
2338 | char *dp, |
2339 | char *end, |
2340 | int pass, |
2341 | struct list_head *buffer_list) |
2342 | { |
2343 | struct xlog_recover *trans; |
2344 | unsigned int len; |
2345 | int error; |
2346 | |
2347 | /* Do we understand who wrote this op? */ |
2348 | if (ohead->oh_clientid != XFS_TRANSACTION && |
2349 | ohead->oh_clientid != XFS_LOG) { |
2350 | xfs_warn(log->l_mp, "%s: bad clientid 0x%x" , |
2351 | __func__, ohead->oh_clientid); |
2352 | ASSERT(0); |
2353 | return -EFSCORRUPTED; |
2354 | } |
2355 | |
2356 | /* |
2357 | * Check the ophdr contains all the data it is supposed to contain. |
2358 | */ |
2359 | len = be32_to_cpu(ohead->oh_len); |
2360 | if (dp + len > end) { |
2361 | xfs_warn(log->l_mp, "%s: bad length 0x%x" , __func__, len); |
2362 | WARN_ON(1); |
2363 | return -EFSCORRUPTED; |
2364 | } |
2365 | |
2366 | trans = xlog_recover_ophdr_to_trans(rhash, rhead, ohead); |
2367 | if (!trans) { |
2368 | /* nothing to do, so skip over this ophdr */ |
2369 | return 0; |
2370 | } |
2371 | |
2372 | /* |
2373 | * The recovered buffer queue is drained only once we know that all |
2374 | * recovery items for the current LSN have been processed. This is |
2375 | * required because: |
2376 | * |
2377 | * - Buffer write submission updates the metadata LSN of the buffer. |
2378 | * - Log recovery skips items with a metadata LSN >= the current LSN of |
2379 | * the recovery item. |
2380 | * - Separate recovery items against the same metadata buffer can share |
2381 | * a current LSN. I.e., consider that the LSN of a recovery item is |
2382 | * defined as the starting LSN of the first record in which its |
2383 | * transaction appears, that a record can hold multiple transactions, |
2384 | * and/or that a transaction can span multiple records. |
2385 | * |
2386 | * In other words, we are allowed to submit a buffer from log recovery |
2387 | * once per current LSN. Otherwise, we may incorrectly skip recovery |
2388 | * items and cause corruption. |
2389 | * |
2390 | * We don't know up front whether buffers are updated multiple times per |
2391 | * LSN. Therefore, track the current LSN of each commit log record as it |
2392 | * is processed and drain the queue when it changes. Use commit records |
2393 | * because they are ordered correctly by the logging code. |
2394 | */ |
2395 | if (log->l_recovery_lsn != trans->r_lsn && |
2396 | ohead->oh_flags & XLOG_COMMIT_TRANS) { |
2397 | error = xfs_buf_delwri_submit(buffer_list); |
2398 | if (error) |
2399 | return error; |
2400 | log->l_recovery_lsn = trans->r_lsn; |
2401 | } |
2402 | |
2403 | return xlog_recovery_process_trans(log, trans, dp, len, |
2404 | flags: ohead->oh_flags, pass, buffer_list); |
2405 | } |
2406 | |
2407 | /* |
2408 | * There are two valid states of the r_state field. 0 indicates that the |
2409 | * transaction structure is in a normal state. We have either seen the |
2410 | * start of the transaction or the last operation we added was not a partial |
2411 | * operation. If the last operation we added to the transaction was a |
2412 | * partial operation, we need to mark r_state with XLOG_WAS_CONT_TRANS. |
2413 | * |
2414 | * NOTE: skip LRs with 0 data length. |
2415 | */ |
2416 | STATIC int |
2417 | xlog_recover_process_data( |
2418 | struct xlog *log, |
2419 | struct hlist_head rhash[], |
2420 | struct xlog_rec_header *rhead, |
2421 | char *dp, |
2422 | int pass, |
2423 | struct list_head *buffer_list) |
2424 | { |
2425 | struct *ohead; |
2426 | char *end; |
2427 | int num_logops; |
2428 | int error; |
2429 | |
2430 | end = dp + be32_to_cpu(rhead->h_len); |
2431 | num_logops = be32_to_cpu(rhead->h_num_logops); |
2432 | |
2433 | /* check the log format matches our own - else we can't recover */ |
2434 | if (xlog_header_check_recover(log->l_mp, rhead)) |
2435 | return -EIO; |
2436 | |
2437 | trace_xfs_log_recover_record(log, rhead, pass); |
2438 | while ((dp < end) && num_logops) { |
2439 | |
2440 | ohead = (struct xlog_op_header *)dp; |
2441 | dp += sizeof(*ohead); |
2442 | ASSERT(dp <= end); |
2443 | |
2444 | /* errors will abort recovery */ |
2445 | error = xlog_recover_process_ophdr(log, rhash, rhead, ohead, |
2446 | dp, end, pass, buffer_list); |
2447 | if (error) |
2448 | return error; |
2449 | |
2450 | dp += be32_to_cpu(ohead->oh_len); |
2451 | num_logops--; |
2452 | } |
2453 | return 0; |
2454 | } |
2455 | |
2456 | /* Take all the collected deferred ops and finish them in order. */ |
2457 | static int |
2458 | xlog_finish_defer_ops( |
2459 | struct xfs_mount *mp, |
2460 | struct list_head *capture_list) |
2461 | { |
2462 | struct xfs_defer_capture *dfc, *next; |
2463 | struct xfs_trans *tp; |
2464 | int error = 0; |
2465 | |
2466 | list_for_each_entry_safe(dfc, next, capture_list, dfc_list) { |
2467 | struct xfs_trans_res resv; |
2468 | struct xfs_defer_resources dres; |
2469 | |
2470 | /* |
2471 | * Create a new transaction reservation from the captured |
2472 | * information. Set logcount to 1 to force the new transaction |
2473 | * to regrant every roll so that we can make forward progress |
2474 | * in recovery no matter how full the log might be. |
2475 | */ |
2476 | resv.tr_logres = dfc->dfc_logres; |
2477 | resv.tr_logcount = 1; |
2478 | resv.tr_logflags = XFS_TRANS_PERM_LOG_RES; |
2479 | |
2480 | error = xfs_trans_alloc(mp, &resv, dfc->dfc_blkres, |
2481 | dfc->dfc_rtxres, XFS_TRANS_RESERVE, &tp); |
2482 | if (error) { |
2483 | xlog_force_shutdown(log: mp->m_log, SHUTDOWN_LOG_IO_ERROR); |
2484 | return error; |
2485 | } |
2486 | |
2487 | /* |
2488 | * Transfer to this new transaction all the dfops we captured |
2489 | * from recovering a single intent item. |
2490 | */ |
2491 | list_del_init(entry: &dfc->dfc_list); |
2492 | xfs_defer_ops_continue(dfc, tp, &dres); |
2493 | error = xfs_trans_commit(tp); |
2494 | xfs_defer_resources_rele(&dres); |
2495 | if (error) |
2496 | return error; |
2497 | } |
2498 | |
2499 | ASSERT(list_empty(capture_list)); |
2500 | return 0; |
2501 | } |
2502 | |
2503 | /* Release all the captured defer ops and capture structures in this list. */ |
2504 | static void |
2505 | xlog_abort_defer_ops( |
2506 | struct xfs_mount *mp, |
2507 | struct list_head *capture_list) |
2508 | { |
2509 | struct xfs_defer_capture *dfc; |
2510 | struct xfs_defer_capture *next; |
2511 | |
2512 | list_for_each_entry_safe(dfc, next, capture_list, dfc_list) { |
2513 | list_del_init(entry: &dfc->dfc_list); |
2514 | xfs_defer_ops_capture_free(mp, dfc); |
2515 | } |
2516 | } |
2517 | |
2518 | /* |
2519 | * When this is called, all of the log intent items which did not have |
2520 | * corresponding log done items should be in the AIL. What we do now is update |
2521 | * the data structures associated with each one. |
2522 | * |
2523 | * Since we process the log intent items in normal transactions, they will be |
2524 | * removed at some point after the commit. This prevents us from just walking |
2525 | * down the list processing each one. We'll use a flag in the intent item to |
2526 | * skip those that we've already processed and use the AIL iteration mechanism's |
2527 | * generation count to try to speed this up at least a bit. |
2528 | * |
2529 | * When we start, we know that the intents are the only things in the AIL. As we |
2530 | * process them, however, other items are added to the AIL. Hence we know we |
2531 | * have started recovery on all the pending intents when we find an non-intent |
2532 | * item in the AIL. |
2533 | */ |
2534 | STATIC int |
2535 | xlog_recover_process_intents( |
2536 | struct xlog *log) |
2537 | { |
2538 | LIST_HEAD(capture_list); |
2539 | struct xfs_ail_cursor cur; |
2540 | struct xfs_log_item *lip; |
2541 | struct xfs_ail *ailp; |
2542 | int error = 0; |
2543 | #if defined(DEBUG) || defined(XFS_WARN) |
2544 | xfs_lsn_t last_lsn; |
2545 | #endif |
2546 | |
2547 | ailp = log->l_ailp; |
2548 | spin_lock(lock: &ailp->ail_lock); |
2549 | #if defined(DEBUG) || defined(XFS_WARN) |
2550 | last_lsn = xlog_assign_lsn(log->l_curr_cycle, log->l_curr_block); |
2551 | #endif |
2552 | for (lip = xfs_trans_ail_cursor_first(ailp, &cur, 0); |
2553 | lip != NULL; |
2554 | lip = xfs_trans_ail_cursor_next(ailp, cur: &cur)) { |
2555 | const struct xfs_item_ops *ops; |
2556 | |
2557 | if (!xlog_item_is_intent(lip)) |
2558 | break; |
2559 | |
2560 | /* |
2561 | * We should never see a redo item with a LSN higher than |
2562 | * the last transaction we found in the log at the start |
2563 | * of recovery. |
2564 | */ |
2565 | ASSERT(XFS_LSN_CMP(last_lsn, lip->li_lsn) >= 0); |
2566 | |
2567 | /* |
2568 | * NOTE: If your intent processing routine can create more |
2569 | * deferred ops, you /must/ attach them to the capture list in |
2570 | * the recover routine or else those subsequent intents will be |
2571 | * replayed in the wrong order! |
2572 | * |
2573 | * The recovery function can free the log item, so we must not |
2574 | * access lip after it returns. |
2575 | */ |
2576 | spin_unlock(lock: &ailp->ail_lock); |
2577 | ops = lip->li_ops; |
2578 | error = ops->iop_recover(lip, &capture_list); |
2579 | spin_lock(lock: &ailp->ail_lock); |
2580 | if (error) { |
2581 | trace_xlog_intent_recovery_failed(mp: log->l_mp, error, |
2582 | function: ops->iop_recover); |
2583 | break; |
2584 | } |
2585 | } |
2586 | |
2587 | xfs_trans_ail_cursor_done(cur: &cur); |
2588 | spin_unlock(lock: &ailp->ail_lock); |
2589 | if (error) |
2590 | goto err; |
2591 | |
2592 | error = xlog_finish_defer_ops(mp: log->l_mp, capture_list: &capture_list); |
2593 | if (error) |
2594 | goto err; |
2595 | |
2596 | return 0; |
2597 | err: |
2598 | xlog_abort_defer_ops(mp: log->l_mp, capture_list: &capture_list); |
2599 | return error; |
2600 | } |
2601 | |
2602 | /* |
2603 | * A cancel occurs when the mount has failed and we're bailing out. Release all |
2604 | * pending log intent items that we haven't started recovery on so they don't |
2605 | * pin the AIL. |
2606 | */ |
2607 | STATIC void |
2608 | xlog_recover_cancel_intents( |
2609 | struct xlog *log) |
2610 | { |
2611 | struct xfs_log_item *lip; |
2612 | struct xfs_ail_cursor cur; |
2613 | struct xfs_ail *ailp; |
2614 | |
2615 | ailp = log->l_ailp; |
2616 | spin_lock(lock: &ailp->ail_lock); |
2617 | lip = xfs_trans_ail_cursor_first(ailp, &cur, 0); |
2618 | while (lip != NULL) { |
2619 | if (!xlog_item_is_intent(lip)) |
2620 | break; |
2621 | |
2622 | spin_unlock(lock: &ailp->ail_lock); |
2623 | lip->li_ops->iop_release(lip); |
2624 | spin_lock(lock: &ailp->ail_lock); |
2625 | lip = xfs_trans_ail_cursor_next(ailp, cur: &cur); |
2626 | } |
2627 | |
2628 | xfs_trans_ail_cursor_done(cur: &cur); |
2629 | spin_unlock(lock: &ailp->ail_lock); |
2630 | } |
2631 | |
2632 | /* |
2633 | * This routine performs a transaction to null out a bad inode pointer |
2634 | * in an agi unlinked inode hash bucket. |
2635 | */ |
2636 | STATIC void |
2637 | xlog_recover_clear_agi_bucket( |
2638 | struct xfs_perag *pag, |
2639 | int bucket) |
2640 | { |
2641 | struct xfs_mount *mp = pag->pag_mount; |
2642 | struct xfs_trans *tp; |
2643 | struct xfs_agi *agi; |
2644 | struct xfs_buf *agibp; |
2645 | int offset; |
2646 | int error; |
2647 | |
2648 | error = xfs_trans_alloc(mp, resp: &M_RES(mp)->tr_clearagi, blocks: 0, rtextents: 0, flags: 0, tpp: &tp); |
2649 | if (error) |
2650 | goto out_error; |
2651 | |
2652 | error = xfs_read_agi(pag, tp, &agibp); |
2653 | if (error) |
2654 | goto out_abort; |
2655 | |
2656 | agi = agibp->b_addr; |
2657 | agi->agi_unlinked[bucket] = cpu_to_be32(NULLAGINO); |
2658 | offset = offsetof(xfs_agi_t, agi_unlinked) + |
2659 | (sizeof(xfs_agino_t) * bucket); |
2660 | xfs_trans_log_buf(tp, agibp, offset, |
2661 | (offset + sizeof(xfs_agino_t) - 1)); |
2662 | |
2663 | error = xfs_trans_commit(tp); |
2664 | if (error) |
2665 | goto out_error; |
2666 | return; |
2667 | |
2668 | out_abort: |
2669 | xfs_trans_cancel(tp); |
2670 | out_error: |
2671 | xfs_warn(mp, "%s: failed to clear agi %d. Continuing." , __func__, |
2672 | pag->pag_agno); |
2673 | return; |
2674 | } |
2675 | |
2676 | static int |
2677 | xlog_recover_iunlink_bucket( |
2678 | struct xfs_perag *pag, |
2679 | struct xfs_agi *agi, |
2680 | int bucket) |
2681 | { |
2682 | struct xfs_mount *mp = pag->pag_mount; |
2683 | struct xfs_inode *prev_ip = NULL; |
2684 | struct xfs_inode *ip; |
2685 | xfs_agino_t prev_agino, agino; |
2686 | int error = 0; |
2687 | |
2688 | agino = be32_to_cpu(agi->agi_unlinked[bucket]); |
2689 | while (agino != NULLAGINO) { |
2690 | error = xfs_iget(mp, NULL, |
2691 | XFS_AGINO_TO_INO(mp, pag->pag_agno, agino), |
2692 | 0, 0, &ip); |
2693 | if (error) |
2694 | break; |
2695 | |
2696 | ASSERT(VFS_I(ip)->i_nlink == 0); |
2697 | ASSERT(VFS_I(ip)->i_mode != 0); |
2698 | xfs_iflags_clear(ip, XFS_IRECOVERY); |
2699 | agino = ip->i_next_unlinked; |
2700 | |
2701 | if (prev_ip) { |
2702 | ip->i_prev_unlinked = prev_agino; |
2703 | xfs_irele(ip: prev_ip); |
2704 | |
2705 | /* |
2706 | * Ensure the inode is removed from the unlinked list |
2707 | * before we continue so that it won't race with |
2708 | * building the in-memory list here. This could be |
2709 | * serialised with the agibp lock, but that just |
2710 | * serialises via lockstepping and it's much simpler |
2711 | * just to flush the inodegc queue and wait for it to |
2712 | * complete. |
2713 | */ |
2714 | error = xfs_inodegc_flush(mp); |
2715 | if (error) |
2716 | break; |
2717 | } |
2718 | |
2719 | prev_agino = agino; |
2720 | prev_ip = ip; |
2721 | } |
2722 | |
2723 | if (prev_ip) { |
2724 | int error2; |
2725 | |
2726 | ip->i_prev_unlinked = prev_agino; |
2727 | xfs_irele(ip: prev_ip); |
2728 | |
2729 | error2 = xfs_inodegc_flush(mp); |
2730 | if (error2 && !error) |
2731 | return error2; |
2732 | } |
2733 | return error; |
2734 | } |
2735 | |
2736 | /* |
2737 | * Recover AGI unlinked lists |
2738 | * |
2739 | * This is called during recovery to process any inodes which we unlinked but |
2740 | * not freed when the system crashed. These inodes will be on the lists in the |
2741 | * AGI blocks. What we do here is scan all the AGIs and fully truncate and free |
2742 | * any inodes found on the lists. Each inode is removed from the lists when it |
2743 | * has been fully truncated and is freed. The freeing of the inode and its |
2744 | * removal from the list must be atomic. |
2745 | * |
2746 | * If everything we touch in the agi processing loop is already in memory, this |
2747 | * loop can hold the cpu for a long time. It runs without lock contention, |
2748 | * memory allocation contention, the need wait for IO, etc, and so will run |
2749 | * until we either run out of inodes to process, run low on memory or we run out |
2750 | * of log space. |
2751 | * |
2752 | * This behaviour is bad for latency on single CPU and non-preemptible kernels, |
2753 | * and can prevent other filesystem work (such as CIL pushes) from running. This |
2754 | * can lead to deadlocks if the recovery process runs out of log reservation |
2755 | * space. Hence we need to yield the CPU when there is other kernel work |
2756 | * scheduled on this CPU to ensure other scheduled work can run without undue |
2757 | * latency. |
2758 | */ |
2759 | static void |
2760 | xlog_recover_iunlink_ag( |
2761 | struct xfs_perag *pag) |
2762 | { |
2763 | struct xfs_agi *agi; |
2764 | struct xfs_buf *agibp; |
2765 | int bucket; |
2766 | int error; |
2767 | |
2768 | error = xfs_read_agi(pag, NULL, &agibp); |
2769 | if (error) { |
2770 | /* |
2771 | * AGI is b0rked. Don't process it. |
2772 | * |
2773 | * We should probably mark the filesystem as corrupt after we've |
2774 | * recovered all the ag's we can.... |
2775 | */ |
2776 | return; |
2777 | } |
2778 | |
2779 | /* |
2780 | * Unlock the buffer so that it can be acquired in the normal course of |
2781 | * the transaction to truncate and free each inode. Because we are not |
2782 | * racing with anyone else here for the AGI buffer, we don't even need |
2783 | * to hold it locked to read the initial unlinked bucket entries out of |
2784 | * the buffer. We keep buffer reference though, so that it stays pinned |
2785 | * in memory while we need the buffer. |
2786 | */ |
2787 | agi = agibp->b_addr; |
2788 | xfs_buf_unlock(agibp); |
2789 | |
2790 | for (bucket = 0; bucket < XFS_AGI_UNLINKED_BUCKETS; bucket++) { |
2791 | error = xlog_recover_iunlink_bucket(pag, agi, bucket); |
2792 | if (error) { |
2793 | /* |
2794 | * Bucket is unrecoverable, so only a repair scan can |
2795 | * free the remaining unlinked inodes. Just empty the |
2796 | * bucket and remaining inodes on it unreferenced and |
2797 | * unfreeable. |
2798 | */ |
2799 | xlog_recover_clear_agi_bucket(pag, bucket); |
2800 | } |
2801 | } |
2802 | |
2803 | xfs_buf_rele(agibp); |
2804 | } |
2805 | |
2806 | static void |
2807 | xlog_recover_process_iunlinks( |
2808 | struct xlog *log) |
2809 | { |
2810 | struct xfs_perag *pag; |
2811 | xfs_agnumber_t agno; |
2812 | |
2813 | for_each_perag(log->l_mp, agno, pag) |
2814 | xlog_recover_iunlink_ag(pag); |
2815 | } |
2816 | |
2817 | STATIC void |
2818 | xlog_unpack_data( |
2819 | struct xlog_rec_header *rhead, |
2820 | char *dp, |
2821 | struct xlog *log) |
2822 | { |
2823 | int i, j, k; |
2824 | |
2825 | for (i = 0; i < BTOBB(be32_to_cpu(rhead->h_len)) && |
2826 | i < (XLOG_HEADER_CYCLE_SIZE / BBSIZE); i++) { |
2827 | *(__be32 *)dp = *(__be32 *)&rhead->h_cycle_data[i]; |
2828 | dp += BBSIZE; |
2829 | } |
2830 | |
2831 | if (xfs_has_logv2(mp: log->l_mp)) { |
2832 | xlog_in_core_2_t *xhdr = (xlog_in_core_2_t *)rhead; |
2833 | for ( ; i < BTOBB(be32_to_cpu(rhead->h_len)); i++) { |
2834 | j = i / (XLOG_HEADER_CYCLE_SIZE / BBSIZE); |
2835 | k = i % (XLOG_HEADER_CYCLE_SIZE / BBSIZE); |
2836 | *(__be32 *)dp = xhdr[j].hic_xheader.xh_cycle_data[k]; |
2837 | dp += BBSIZE; |
2838 | } |
2839 | } |
2840 | } |
2841 | |
2842 | /* |
2843 | * CRC check, unpack and process a log record. |
2844 | */ |
2845 | STATIC int |
2846 | xlog_recover_process( |
2847 | struct xlog *log, |
2848 | struct hlist_head rhash[], |
2849 | struct xlog_rec_header *rhead, |
2850 | char *dp, |
2851 | int pass, |
2852 | struct list_head *buffer_list) |
2853 | { |
2854 | __le32 old_crc = rhead->h_crc; |
2855 | __le32 crc; |
2856 | |
2857 | crc = xlog_cksum(log, rhead, dp, be32_to_cpu(rhead->h_len)); |
2858 | |
2859 | /* |
2860 | * Nothing else to do if this is a CRC verification pass. Just return |
2861 | * if this a record with a non-zero crc. Unfortunately, mkfs always |
2862 | * sets old_crc to 0 so we must consider this valid even on v5 supers. |
2863 | * Otherwise, return EFSBADCRC on failure so the callers up the stack |
2864 | * know precisely what failed. |
2865 | */ |
2866 | if (pass == XLOG_RECOVER_CRCPASS) { |
2867 | if (old_crc && crc != old_crc) |
2868 | return -EFSBADCRC; |
2869 | return 0; |
2870 | } |
2871 | |
2872 | /* |
2873 | * We're in the normal recovery path. Issue a warning if and only if the |
2874 | * CRC in the header is non-zero. This is an advisory warning and the |
2875 | * zero CRC check prevents warnings from being emitted when upgrading |
2876 | * the kernel from one that does not add CRCs by default. |
2877 | */ |
2878 | if (crc != old_crc) { |
2879 | if (old_crc || xfs_has_crc(mp: log->l_mp)) { |
2880 | xfs_alert(log->l_mp, |
2881 | "log record CRC mismatch: found 0x%x, expected 0x%x." , |
2882 | le32_to_cpu(old_crc), |
2883 | le32_to_cpu(crc)); |
2884 | xfs_hex_dump(p: dp, length: 32); |
2885 | } |
2886 | |
2887 | /* |
2888 | * If the filesystem is CRC enabled, this mismatch becomes a |
2889 | * fatal log corruption failure. |
2890 | */ |
2891 | if (xfs_has_crc(mp: log->l_mp)) { |
2892 | XFS_ERROR_REPORT(__func__, XFS_ERRLEVEL_LOW, log->l_mp); |
2893 | return -EFSCORRUPTED; |
2894 | } |
2895 | } |
2896 | |
2897 | xlog_unpack_data(rhead, dp, log); |
2898 | |
2899 | return xlog_recover_process_data(log, rhash, rhead, dp, pass, |
2900 | buffer_list); |
2901 | } |
2902 | |
2903 | STATIC int |
2904 | ( |
2905 | struct xlog *log, |
2906 | struct xlog_rec_header *rhead, |
2907 | xfs_daddr_t blkno, |
2908 | int bufsize) |
2909 | { |
2910 | int hlen; |
2911 | |
2912 | if (XFS_IS_CORRUPT(log->l_mp, |
2913 | rhead->h_magicno != cpu_to_be32(XLOG_HEADER_MAGIC_NUM))) |
2914 | return -EFSCORRUPTED; |
2915 | if (XFS_IS_CORRUPT(log->l_mp, |
2916 | (!rhead->h_version || |
2917 | (be32_to_cpu(rhead->h_version) & |
2918 | (~XLOG_VERSION_OKBITS))))) { |
2919 | xfs_warn(log->l_mp, "%s: unrecognised log version (%d)." , |
2920 | __func__, be32_to_cpu(rhead->h_version)); |
2921 | return -EFSCORRUPTED; |
2922 | } |
2923 | |
2924 | /* |
2925 | * LR body must have data (or it wouldn't have been written) |
2926 | * and h_len must not be greater than LR buffer size. |
2927 | */ |
2928 | hlen = be32_to_cpu(rhead->h_len); |
2929 | if (XFS_IS_CORRUPT(log->l_mp, hlen <= 0 || hlen > bufsize)) |
2930 | return -EFSCORRUPTED; |
2931 | |
2932 | if (XFS_IS_CORRUPT(log->l_mp, |
2933 | blkno > log->l_logBBsize || blkno > INT_MAX)) |
2934 | return -EFSCORRUPTED; |
2935 | return 0; |
2936 | } |
2937 | |
2938 | /* |
2939 | * Read the log from tail to head and process the log records found. |
2940 | * Handle the two cases where the tail and head are in the same cycle |
2941 | * and where the active portion of the log wraps around the end of |
2942 | * the physical log separately. The pass parameter is passed through |
2943 | * to the routines called to process the data and is not looked at |
2944 | * here. |
2945 | */ |
2946 | STATIC int |
2947 | xlog_do_recovery_pass( |
2948 | struct xlog *log, |
2949 | xfs_daddr_t head_blk, |
2950 | xfs_daddr_t tail_blk, |
2951 | int pass, |
2952 | xfs_daddr_t *first_bad) /* out: first bad log rec */ |
2953 | { |
2954 | xlog_rec_header_t *rhead; |
2955 | xfs_daddr_t blk_no, rblk_no; |
2956 | xfs_daddr_t rhead_blk; |
2957 | char *offset; |
2958 | char *hbp, *dbp; |
2959 | int error = 0, h_size, h_len; |
2960 | int error2 = 0; |
2961 | int bblks, split_bblks; |
2962 | int hblks, split_hblks, wrapped_hblks; |
2963 | int i; |
2964 | struct hlist_head rhash[XLOG_RHASH_SIZE]; |
2965 | LIST_HEAD (buffer_list); |
2966 | |
2967 | ASSERT(head_blk != tail_blk); |
2968 | blk_no = rhead_blk = tail_blk; |
2969 | |
2970 | for (i = 0; i < XLOG_RHASH_SIZE; i++) |
2971 | INIT_HLIST_HEAD(&rhash[i]); |
2972 | |
2973 | /* |
2974 | * Read the header of the tail block and get the iclog buffer size from |
2975 | * h_size. Use this to tell how many sectors make up the log header. |
2976 | */ |
2977 | if (xfs_has_logv2(mp: log->l_mp)) { |
2978 | /* |
2979 | * When using variable length iclogs, read first sector of |
2980 | * iclog header and extract the header size from it. Get a |
2981 | * new hbp that is the correct size. |
2982 | */ |
2983 | hbp = xlog_alloc_buffer(log, nbblks: 1); |
2984 | if (!hbp) |
2985 | return -ENOMEM; |
2986 | |
2987 | error = xlog_bread(log, blk_no: tail_blk, nbblks: 1, data: hbp, offset: &offset); |
2988 | if (error) |
2989 | goto bread_err1; |
2990 | |
2991 | rhead = (xlog_rec_header_t *)offset; |
2992 | |
2993 | /* |
2994 | * xfsprogs has a bug where record length is based on lsunit but |
2995 | * h_size (iclog size) is hardcoded to 32k. Now that we |
2996 | * unconditionally CRC verify the unmount record, this means the |
2997 | * log buffer can be too small for the record and cause an |
2998 | * overrun. |
2999 | * |
3000 | * Detect this condition here. Use lsunit for the buffer size as |
3001 | * long as this looks like the mkfs case. Otherwise, return an |
3002 | * error to avoid a buffer overrun. |
3003 | */ |
3004 | h_size = be32_to_cpu(rhead->h_size); |
3005 | h_len = be32_to_cpu(rhead->h_len); |
3006 | if (h_len > h_size && h_len <= log->l_mp->m_logbsize && |
3007 | rhead->h_num_logops == cpu_to_be32(1)) { |
3008 | xfs_warn(log->l_mp, |
3009 | "invalid iclog size (%d bytes), using lsunit (%d bytes)" , |
3010 | h_size, log->l_mp->m_logbsize); |
3011 | h_size = log->l_mp->m_logbsize; |
3012 | } |
3013 | |
3014 | error = xlog_valid_rec_header(log, rhead, tail_blk, h_size); |
3015 | if (error) |
3016 | goto bread_err1; |
3017 | |
3018 | hblks = xlog_logrec_hblks(log, rhead); |
3019 | if (hblks != 1) { |
3020 | kmem_free(ptr: hbp); |
3021 | hbp = xlog_alloc_buffer(log, nbblks: hblks); |
3022 | } |
3023 | } else { |
3024 | ASSERT(log->l_sectBBsize == 1); |
3025 | hblks = 1; |
3026 | hbp = xlog_alloc_buffer(log, nbblks: 1); |
3027 | h_size = XLOG_BIG_RECORD_BSIZE; |
3028 | } |
3029 | |
3030 | if (!hbp) |
3031 | return -ENOMEM; |
3032 | dbp = xlog_alloc_buffer(log, nbblks: BTOBB(h_size)); |
3033 | if (!dbp) { |
3034 | kmem_free(ptr: hbp); |
3035 | return -ENOMEM; |
3036 | } |
3037 | |
3038 | memset(rhash, 0, sizeof(rhash)); |
3039 | if (tail_blk > head_blk) { |
3040 | /* |
3041 | * Perform recovery around the end of the physical log. |
3042 | * When the head is not on the same cycle number as the tail, |
3043 | * we can't do a sequential recovery. |
3044 | */ |
3045 | while (blk_no < log->l_logBBsize) { |
3046 | /* |
3047 | * Check for header wrapping around physical end-of-log |
3048 | */ |
3049 | offset = hbp; |
3050 | split_hblks = 0; |
3051 | wrapped_hblks = 0; |
3052 | if (blk_no + hblks <= log->l_logBBsize) { |
3053 | /* Read header in one read */ |
3054 | error = xlog_bread(log, blk_no, nbblks: hblks, data: hbp, |
3055 | offset: &offset); |
3056 | if (error) |
3057 | goto bread_err2; |
3058 | } else { |
3059 | /* This LR is split across physical log end */ |
3060 | if (blk_no != log->l_logBBsize) { |
3061 | /* some data before physical log end */ |
3062 | ASSERT(blk_no <= INT_MAX); |
3063 | split_hblks = log->l_logBBsize - (int)blk_no; |
3064 | ASSERT(split_hblks > 0); |
3065 | error = xlog_bread(log, blk_no, |
3066 | nbblks: split_hblks, data: hbp, |
3067 | offset: &offset); |
3068 | if (error) |
3069 | goto bread_err2; |
3070 | } |
3071 | |
3072 | /* |
3073 | * Note: this black magic still works with |
3074 | * large sector sizes (non-512) only because: |
3075 | * - we increased the buffer size originally |
3076 | * by 1 sector giving us enough extra space |
3077 | * for the second read; |
3078 | * - the log start is guaranteed to be sector |
3079 | * aligned; |
3080 | * - we read the log end (LR header start) |
3081 | * _first_, then the log start (LR header end) |
3082 | * - order is important. |
3083 | */ |
3084 | wrapped_hblks = hblks - split_hblks; |
3085 | error = xlog_bread_noalign(log, blk_no: 0, |
3086 | nbblks: wrapped_hblks, |
3087 | data: offset + BBTOB(split_hblks)); |
3088 | if (error) |
3089 | goto bread_err2; |
3090 | } |
3091 | rhead = (xlog_rec_header_t *)offset; |
3092 | error = xlog_valid_rec_header(log, rhead, |
3093 | split_hblks ? blk_no : 0, h_size); |
3094 | if (error) |
3095 | goto bread_err2; |
3096 | |
3097 | bblks = (int)BTOBB(be32_to_cpu(rhead->h_len)); |
3098 | blk_no += hblks; |
3099 | |
3100 | /* |
3101 | * Read the log record data in multiple reads if it |
3102 | * wraps around the end of the log. Note that if the |
3103 | * header already wrapped, blk_no could point past the |
3104 | * end of the log. The record data is contiguous in |
3105 | * that case. |
3106 | */ |
3107 | if (blk_no + bblks <= log->l_logBBsize || |
3108 | blk_no >= log->l_logBBsize) { |
3109 | rblk_no = xlog_wrap_logbno(log, bno: blk_no); |
3110 | error = xlog_bread(log, blk_no: rblk_no, nbblks: bblks, data: dbp, |
3111 | offset: &offset); |
3112 | if (error) |
3113 | goto bread_err2; |
3114 | } else { |
3115 | /* This log record is split across the |
3116 | * physical end of log */ |
3117 | offset = dbp; |
3118 | split_bblks = 0; |
3119 | if (blk_no != log->l_logBBsize) { |
3120 | /* some data is before the physical |
3121 | * end of log */ |
3122 | ASSERT(!wrapped_hblks); |
3123 | ASSERT(blk_no <= INT_MAX); |
3124 | split_bblks = |
3125 | log->l_logBBsize - (int)blk_no; |
3126 | ASSERT(split_bblks > 0); |
3127 | error = xlog_bread(log, blk_no, |
3128 | nbblks: split_bblks, data: dbp, |
3129 | offset: &offset); |
3130 | if (error) |
3131 | goto bread_err2; |
3132 | } |
3133 | |
3134 | /* |
3135 | * Note: this black magic still works with |
3136 | * large sector sizes (non-512) only because: |
3137 | * - we increased the buffer size originally |
3138 | * by 1 sector giving us enough extra space |
3139 | * for the second read; |
3140 | * - the log start is guaranteed to be sector |
3141 | * aligned; |
3142 | * - we read the log end (LR header start) |
3143 | * _first_, then the log start (LR header end) |
3144 | * - order is important. |
3145 | */ |
3146 | error = xlog_bread_noalign(log, blk_no: 0, |
3147 | nbblks: bblks - split_bblks, |
3148 | data: offset + BBTOB(split_bblks)); |
3149 | if (error) |
3150 | goto bread_err2; |
3151 | } |
3152 | |
3153 | error = xlog_recover_process(log, rhash, rhead, offset, |
3154 | pass, &buffer_list); |
3155 | if (error) |
3156 | goto bread_err2; |
3157 | |
3158 | blk_no += bblks; |
3159 | rhead_blk = blk_no; |
3160 | } |
3161 | |
3162 | ASSERT(blk_no >= log->l_logBBsize); |
3163 | blk_no -= log->l_logBBsize; |
3164 | rhead_blk = blk_no; |
3165 | } |
3166 | |
3167 | /* read first part of physical log */ |
3168 | while (blk_no < head_blk) { |
3169 | error = xlog_bread(log, blk_no, nbblks: hblks, data: hbp, offset: &offset); |
3170 | if (error) |
3171 | goto bread_err2; |
3172 | |
3173 | rhead = (xlog_rec_header_t *)offset; |
3174 | error = xlog_valid_rec_header(log, rhead, blk_no, h_size); |
3175 | if (error) |
3176 | goto bread_err2; |
3177 | |
3178 | /* blocks in data section */ |
3179 | bblks = (int)BTOBB(be32_to_cpu(rhead->h_len)); |
3180 | error = xlog_bread(log, blk_no: blk_no+hblks, nbblks: bblks, data: dbp, |
3181 | offset: &offset); |
3182 | if (error) |
3183 | goto bread_err2; |
3184 | |
3185 | error = xlog_recover_process(log, rhash, rhead, offset, pass, |
3186 | &buffer_list); |
3187 | if (error) |
3188 | goto bread_err2; |
3189 | |
3190 | blk_no += bblks + hblks; |
3191 | rhead_blk = blk_no; |
3192 | } |
3193 | |
3194 | bread_err2: |
3195 | kmem_free(ptr: dbp); |
3196 | bread_err1: |
3197 | kmem_free(ptr: hbp); |
3198 | |
3199 | /* |
3200 | * Submit buffers that have been added from the last record processed, |
3201 | * regardless of error status. |
3202 | */ |
3203 | if (!list_empty(head: &buffer_list)) |
3204 | error2 = xfs_buf_delwri_submit(&buffer_list); |
3205 | |
3206 | if (error && first_bad) |
3207 | *first_bad = rhead_blk; |
3208 | |
3209 | /* |
3210 | * Transactions are freed at commit time but transactions without commit |
3211 | * records on disk are never committed. Free any that may be left in the |
3212 | * hash table. |
3213 | */ |
3214 | for (i = 0; i < XLOG_RHASH_SIZE; i++) { |
3215 | struct hlist_node *tmp; |
3216 | struct xlog_recover *trans; |
3217 | |
3218 | hlist_for_each_entry_safe(trans, tmp, &rhash[i], r_list) |
3219 | xlog_recover_free_trans(trans); |
3220 | } |
3221 | |
3222 | return error ? error : error2; |
3223 | } |
3224 | |
3225 | /* |
3226 | * Do the recovery of the log. We actually do this in two phases. |
3227 | * The two passes are necessary in order to implement the function |
3228 | * of cancelling a record written into the log. The first pass |
3229 | * determines those things which have been cancelled, and the |
3230 | * second pass replays log items normally except for those which |
3231 | * have been cancelled. The handling of the replay and cancellations |
3232 | * takes place in the log item type specific routines. |
3233 | * |
3234 | * The table of items which have cancel records in the log is allocated |
3235 | * and freed at this level, since only here do we know when all of |
3236 | * the log recovery has been completed. |
3237 | */ |
3238 | STATIC int |
3239 | xlog_do_log_recovery( |
3240 | struct xlog *log, |
3241 | xfs_daddr_t head_blk, |
3242 | xfs_daddr_t tail_blk) |
3243 | { |
3244 | int error; |
3245 | |
3246 | ASSERT(head_blk != tail_blk); |
3247 | |
3248 | /* |
3249 | * First do a pass to find all of the cancelled buf log items. |
3250 | * Store them in the buf_cancel_table for use in the second pass. |
3251 | */ |
3252 | error = xlog_alloc_buf_cancel_table(log); |
3253 | if (error) |
3254 | return error; |
3255 | |
3256 | error = xlog_do_recovery_pass(log, head_blk, tail_blk, |
3257 | XLOG_RECOVER_PASS1, NULL); |
3258 | if (error != 0) |
3259 | goto out_cancel; |
3260 | |
3261 | /* |
3262 | * Then do a second pass to actually recover the items in the log. |
3263 | * When it is complete free the table of buf cancel items. |
3264 | */ |
3265 | error = xlog_do_recovery_pass(log, head_blk, tail_blk, |
3266 | XLOG_RECOVER_PASS2, NULL); |
3267 | if (!error) |
3268 | xlog_check_buf_cancel_table(log); |
3269 | out_cancel: |
3270 | xlog_free_buf_cancel_table(log); |
3271 | return error; |
3272 | } |
3273 | |
3274 | /* |
3275 | * Do the actual recovery |
3276 | */ |
3277 | STATIC int |
3278 | xlog_do_recover( |
3279 | struct xlog *log, |
3280 | xfs_daddr_t head_blk, |
3281 | xfs_daddr_t tail_blk) |
3282 | { |
3283 | struct xfs_mount *mp = log->l_mp; |
3284 | struct xfs_buf *bp = mp->m_sb_bp; |
3285 | struct xfs_sb *sbp = &mp->m_sb; |
3286 | int error; |
3287 | |
3288 | trace_xfs_log_recover(log, headblk: head_blk, tailblk: tail_blk); |
3289 | |
3290 | /* |
3291 | * First replay the images in the log. |
3292 | */ |
3293 | error = xlog_do_log_recovery(log, head_blk, tail_blk); |
3294 | if (error) |
3295 | return error; |
3296 | |
3297 | if (xlog_is_shutdown(log)) |
3298 | return -EIO; |
3299 | |
3300 | /* |
3301 | * We now update the tail_lsn since much of the recovery has completed |
3302 | * and there may be space available to use. If there were no extent |
3303 | * or iunlinks, we can free up the entire log and set the tail_lsn to |
3304 | * be the last_sync_lsn. This was set in xlog_find_tail to be the |
3305 | * lsn of the last known good LR on disk. If there are extent frees |
3306 | * or iunlinks they will have some entries in the AIL; so we look at |
3307 | * the AIL to determine how to set the tail_lsn. |
3308 | */ |
3309 | xlog_assign_tail_lsn(mp); |
3310 | |
3311 | /* |
3312 | * Now that we've finished replaying all buffer and inode updates, |
3313 | * re-read the superblock and reverify it. |
3314 | */ |
3315 | xfs_buf_lock(bp); |
3316 | xfs_buf_hold(bp); |
3317 | error = _xfs_buf_read(bp, XBF_READ); |
3318 | if (error) { |
3319 | if (!xlog_is_shutdown(log)) { |
3320 | xfs_buf_ioerror_alert(bp, __this_address); |
3321 | ASSERT(0); |
3322 | } |
3323 | xfs_buf_relse(bp); |
3324 | return error; |
3325 | } |
3326 | |
3327 | /* Convert superblock from on-disk format */ |
3328 | xfs_sb_from_disk(sbp, bp->b_addr); |
3329 | xfs_buf_relse(bp); |
3330 | |
3331 | /* re-initialise in-core superblock and geometry structures */ |
3332 | mp->m_features |= xfs_sb_version_to_features(sbp); |
3333 | xfs_reinit_percpu_counters(mp); |
3334 | error = xfs_initialize_perag(mp, sbp->sb_agcount, sbp->sb_dblocks, |
3335 | &mp->m_maxagi); |
3336 | if (error) { |
3337 | xfs_warn(mp, "Failed post-recovery per-ag init: %d" , error); |
3338 | return error; |
3339 | } |
3340 | mp->m_alloc_set_aside = xfs_alloc_set_aside(mp); |
3341 | |
3342 | /* Normal transactions can now occur */ |
3343 | clear_bit(XLOG_ACTIVE_RECOVERY, addr: &log->l_opstate); |
3344 | return 0; |
3345 | } |
3346 | |
3347 | /* |
3348 | * Perform recovery and re-initialize some log variables in xlog_find_tail. |
3349 | * |
3350 | * Return error or zero. |
3351 | */ |
3352 | int |
3353 | xlog_recover( |
3354 | struct xlog *log) |
3355 | { |
3356 | xfs_daddr_t head_blk, tail_blk; |
3357 | int error; |
3358 | |
3359 | /* find the tail of the log */ |
3360 | error = xlog_find_tail(log, head_blk: &head_blk, tail_blk: &tail_blk); |
3361 | if (error) |
3362 | return error; |
3363 | |
3364 | /* |
3365 | * The superblock was read before the log was available and thus the LSN |
3366 | * could not be verified. Check the superblock LSN against the current |
3367 | * LSN now that it's known. |
3368 | */ |
3369 | if (xfs_has_crc(mp: log->l_mp) && |
3370 | !xfs_log_check_lsn(log->l_mp, xfs_lsn_t: log->l_mp->m_sb.sb_lsn)) |
3371 | return -EINVAL; |
3372 | |
3373 | if (tail_blk != head_blk) { |
3374 | /* There used to be a comment here: |
3375 | * |
3376 | * disallow recovery on read-only mounts. note -- mount |
3377 | * checks for ENOSPC and turns it into an intelligent |
3378 | * error message. |
3379 | * ...but this is no longer true. Now, unless you specify |
3380 | * NORECOVERY (in which case this function would never be |
3381 | * called), we just go ahead and recover. We do this all |
3382 | * under the vfs layer, so we can get away with it unless |
3383 | * the device itself is read-only, in which case we fail. |
3384 | */ |
3385 | if ((error = xfs_dev_is_read_only(log->l_mp, "recovery" ))) { |
3386 | return error; |
3387 | } |
3388 | |
3389 | /* |
3390 | * Version 5 superblock log feature mask validation. We know the |
3391 | * log is dirty so check if there are any unknown log features |
3392 | * in what we need to recover. If there are unknown features |
3393 | * (e.g. unsupported transactions, then simply reject the |
3394 | * attempt at recovery before touching anything. |
3395 | */ |
3396 | if (xfs_sb_is_v5(&log->l_mp->m_sb) && |
3397 | xfs_sb_has_incompat_log_feature(&log->l_mp->m_sb, |
3398 | XFS_SB_FEAT_INCOMPAT_LOG_UNKNOWN)) { |
3399 | xfs_warn(log->l_mp, |
3400 | "Superblock has unknown incompatible log features (0x%x) enabled." , |
3401 | (log->l_mp->m_sb.sb_features_log_incompat & |
3402 | XFS_SB_FEAT_INCOMPAT_LOG_UNKNOWN)); |
3403 | xfs_warn(log->l_mp, |
3404 | "The log can not be fully and/or safely recovered by this kernel." ); |
3405 | xfs_warn(log->l_mp, |
3406 | "Please recover the log on a kernel that supports the unknown features." ); |
3407 | return -EINVAL; |
3408 | } |
3409 | |
3410 | /* |
3411 | * Delay log recovery if the debug hook is set. This is debug |
3412 | * instrumentation to coordinate simulation of I/O failures with |
3413 | * log recovery. |
3414 | */ |
3415 | if (xfs_globals.log_recovery_delay) { |
3416 | xfs_notice(log->l_mp, |
3417 | "Delaying log recovery for %d seconds." , |
3418 | xfs_globals.log_recovery_delay); |
3419 | msleep(msecs: xfs_globals.log_recovery_delay * 1000); |
3420 | } |
3421 | |
3422 | xfs_notice(log->l_mp, "Starting recovery (logdev: %s)" , |
3423 | log->l_mp->m_logname ? log->l_mp->m_logname |
3424 | : "internal" ); |
3425 | |
3426 | error = xlog_do_recover(log, head_blk, tail_blk); |
3427 | set_bit(XLOG_RECOVERY_NEEDED, addr: &log->l_opstate); |
3428 | } |
3429 | return error; |
3430 | } |
3431 | |
3432 | /* |
3433 | * In the first part of recovery we replay inodes and buffers and build up the |
3434 | * list of intents which need to be processed. Here we process the intents and |
3435 | * clean up the on disk unlinked inode lists. This is separated from the first |
3436 | * part of recovery so that the root and real-time bitmap inodes can be read in |
3437 | * from disk in between the two stages. This is necessary so that we can free |
3438 | * space in the real-time portion of the file system. |
3439 | */ |
3440 | int |
3441 | xlog_recover_finish( |
3442 | struct xlog *log) |
3443 | { |
3444 | int error; |
3445 | |
3446 | error = xlog_recover_process_intents(log); |
3447 | if (error) { |
3448 | /* |
3449 | * Cancel all the unprocessed intent items now so that we don't |
3450 | * leave them pinned in the AIL. This can cause the AIL to |
3451 | * livelock on the pinned item if anyone tries to push the AIL |
3452 | * (inode reclaim does this) before we get around to |
3453 | * xfs_log_mount_cancel. |
3454 | */ |
3455 | xlog_recover_cancel_intents(log); |
3456 | xfs_alert(log->l_mp, "Failed to recover intents" ); |
3457 | xlog_force_shutdown(log, SHUTDOWN_LOG_IO_ERROR); |
3458 | return error; |
3459 | } |
3460 | |
3461 | /* |
3462 | * Sync the log to get all the intents out of the AIL. This isn't |
3463 | * absolutely necessary, but it helps in case the unlink transactions |
3464 | * would have problems pushing the intents out of the way. |
3465 | */ |
3466 | xfs_log_force(mp: log->l_mp, XFS_LOG_SYNC); |
3467 | |
3468 | /* |
3469 | * Now that we've recovered the log and all the intents, we can clear |
3470 | * the log incompat feature bits in the superblock because there's no |
3471 | * longer anything to protect. We rely on the AIL push to write out the |
3472 | * updated superblock after everything else. |
3473 | */ |
3474 | if (xfs_clear_incompat_log_features(mp: log->l_mp)) { |
3475 | error = xfs_sync_sb(log->l_mp, false); |
3476 | if (error < 0) { |
3477 | xfs_alert(log->l_mp, |
3478 | "Failed to clear log incompat features on recovery" ); |
3479 | return error; |
3480 | } |
3481 | } |
3482 | |
3483 | xlog_recover_process_iunlinks(log); |
3484 | |
3485 | /* |
3486 | * Recover any CoW staging blocks that are still referenced by the |
3487 | * ondisk refcount metadata. During mount there cannot be any live |
3488 | * staging extents as we have not permitted any user modifications. |
3489 | * Therefore, it is safe to free them all right now, even on a |
3490 | * read-only mount. |
3491 | */ |
3492 | error = xfs_reflink_recover_cow(mp: log->l_mp); |
3493 | if (error) { |
3494 | xfs_alert(log->l_mp, |
3495 | "Failed to recover leftover CoW staging extents, err %d." , |
3496 | error); |
3497 | /* |
3498 | * If we get an error here, make sure the log is shut down |
3499 | * but return zero so that any log items committed since the |
3500 | * end of intents processing can be pushed through the CIL |
3501 | * and AIL. |
3502 | */ |
3503 | xlog_force_shutdown(log, SHUTDOWN_LOG_IO_ERROR); |
3504 | } |
3505 | |
3506 | return 0; |
3507 | } |
3508 | |
3509 | void |
3510 | xlog_recover_cancel( |
3511 | struct xlog *log) |
3512 | { |
3513 | if (xlog_recovery_needed(log)) |
3514 | xlog_recover_cancel_intents(log); |
3515 | } |
3516 | |
3517 | |