1 /*
2 * Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
3 * Copyright (C) 2004-2006 Red Hat, Inc. All rights reserved.
4 *
5 * This copyrighted material is made available to anyone wishing to use,
6 * modify, copy, or redistribute it subject to the terms and conditions
7 * of the GNU General Public License version 2.
8 */
9
10 #include <linux/module.h>
11 #include <linux/slab.h>
12 #include <linux/spinlock.h>
13 #include <linux/completion.h>
14 #include <linux/buffer_head.h>
15 #include <linux/gfs2_ondisk.h>
16 #include <linux/crc32.h>
17 #include <linux/crc32c.h>
18 #include <linux/ktime.h>
19
20 #include "gfs2.h"
21 #include "incore.h"
22 #include "bmap.h"
23 #include "glock.h"
24 #include "glops.h"
25 #include "log.h"
26 #include "lops.h"
27 #include "meta_io.h"
28 #include "recovery.h"
29 #include "super.h"
30 #include "util.h"
31 #include "dir.h"
32
33 struct workqueue_struct *gfs_recovery_wq;
34
gfs2_replay_read_block(struct gfs2_jdesc * jd,unsigned int blk,struct buffer_head ** bh)35 int gfs2_replay_read_block(struct gfs2_jdesc *jd, unsigned int blk,
36 struct buffer_head **bh)
37 {
38 struct gfs2_inode *ip = GFS2_I(jd->jd_inode);
39 struct gfs2_glock *gl = ip->i_gl;
40 int new = 0;
41 u64 dblock;
42 u32 extlen;
43 int error;
44
45 error = gfs2_extent_map(&ip->i_inode, blk, &new, &dblock, &extlen);
46 if (error)
47 return error;
48 if (!dblock) {
49 gfs2_consist_inode(ip);
50 return -EIO;
51 }
52
53 *bh = gfs2_meta_ra(gl, dblock, extlen);
54
55 return error;
56 }
57
gfs2_revoke_add(struct gfs2_jdesc * jd,u64 blkno,unsigned int where)58 int gfs2_revoke_add(struct gfs2_jdesc *jd, u64 blkno, unsigned int where)
59 {
60 struct list_head *head = &jd->jd_revoke_list;
61 struct gfs2_revoke_replay *rr;
62 int found = 0;
63
64 list_for_each_entry(rr, head, rr_list) {
65 if (rr->rr_blkno == blkno) {
66 found = 1;
67 break;
68 }
69 }
70
71 if (found) {
72 rr->rr_where = where;
73 return 0;
74 }
75
76 rr = kmalloc(sizeof(struct gfs2_revoke_replay), GFP_NOFS);
77 if (!rr)
78 return -ENOMEM;
79
80 rr->rr_blkno = blkno;
81 rr->rr_where = where;
82 list_add(&rr->rr_list, head);
83
84 return 1;
85 }
86
gfs2_revoke_check(struct gfs2_jdesc * jd,u64 blkno,unsigned int where)87 int gfs2_revoke_check(struct gfs2_jdesc *jd, u64 blkno, unsigned int where)
88 {
89 struct gfs2_revoke_replay *rr;
90 int wrap, a, b, revoke;
91 int found = 0;
92
93 list_for_each_entry(rr, &jd->jd_revoke_list, rr_list) {
94 if (rr->rr_blkno == blkno) {
95 found = 1;
96 break;
97 }
98 }
99
100 if (!found)
101 return 0;
102
103 wrap = (rr->rr_where < jd->jd_replay_tail);
104 a = (jd->jd_replay_tail < where);
105 b = (where < rr->rr_where);
106 revoke = (wrap) ? (a || b) : (a && b);
107
108 return revoke;
109 }
110
gfs2_revoke_clean(struct gfs2_jdesc * jd)111 void gfs2_revoke_clean(struct gfs2_jdesc *jd)
112 {
113 struct list_head *head = &jd->jd_revoke_list;
114 struct gfs2_revoke_replay *rr;
115
116 while (!list_empty(head)) {
117 rr = list_entry(head->next, struct gfs2_revoke_replay, rr_list);
118 list_del(&rr->rr_list);
119 kfree(rr);
120 }
121 }
122
123 /**
124 * get_log_header - read the log header for a given segment
125 * @jd: the journal
126 * @blk: the block to look at
127 * @lh: the log header to return
128 *
129 * Read the log header for a given segement in a given journal. Do a few
130 * sanity checks on it.
131 *
132 * Returns: 0 on success,
133 * 1 if the header was invalid or incomplete,
134 * errno on error
135 */
136
get_log_header(struct gfs2_jdesc * jd,unsigned int blk,struct gfs2_log_header_host * head)137 static int get_log_header(struct gfs2_jdesc *jd, unsigned int blk,
138 struct gfs2_log_header_host *head)
139 {
140 struct gfs2_log_header *lh;
141 struct buffer_head *bh;
142 u32 hash, crc;
143 int error;
144
145 error = gfs2_replay_read_block(jd, blk, &bh);
146 if (error)
147 return error;
148 lh = (void *)bh->b_data;
149
150 hash = crc32(~0, lh, LH_V1_SIZE - 4);
151 hash = ~crc32_le_shift(hash, 4); /* assume lh_hash is zero */
152
153 crc = crc32c(~0, (void *)lh + LH_V1_SIZE + 4,
154 bh->b_size - LH_V1_SIZE - 4);
155
156 error = lh->lh_header.mh_magic != cpu_to_be32(GFS2_MAGIC) ||
157 lh->lh_header.mh_type != cpu_to_be32(GFS2_METATYPE_LH) ||
158 be32_to_cpu(lh->lh_blkno) != blk ||
159 be32_to_cpu(lh->lh_hash) != hash ||
160 (lh->lh_crc != 0 && be32_to_cpu(lh->lh_crc) != crc);
161
162 brelse(bh);
163
164 if (!error) {
165 head->lh_sequence = be64_to_cpu(lh->lh_sequence);
166 head->lh_flags = be32_to_cpu(lh->lh_flags);
167 head->lh_tail = be32_to_cpu(lh->lh_tail);
168 head->lh_blkno = be32_to_cpu(lh->lh_blkno);
169 }
170 return error;
171 }
172
173 /**
174 * find_good_lh - find a good log header
175 * @jd: the journal
176 * @blk: the segment to start searching from
177 * @lh: the log header to fill in
178 * @forward: if true search forward in the log, else search backward
179 *
180 * Call get_log_header() to get a log header for a segment, but if the
181 * segment is bad, either scan forward or backward until we find a good one.
182 *
183 * Returns: errno
184 */
185
find_good_lh(struct gfs2_jdesc * jd,unsigned int * blk,struct gfs2_log_header_host * head)186 static int find_good_lh(struct gfs2_jdesc *jd, unsigned int *blk,
187 struct gfs2_log_header_host *head)
188 {
189 unsigned int orig_blk = *blk;
190 int error;
191
192 for (;;) {
193 error = get_log_header(jd, *blk, head);
194 if (error <= 0)
195 return error;
196
197 if (++*blk == jd->jd_blocks)
198 *blk = 0;
199
200 if (*blk == orig_blk) {
201 gfs2_consist_inode(GFS2_I(jd->jd_inode));
202 return -EIO;
203 }
204 }
205 }
206
207 /**
208 * jhead_scan - make sure we've found the head of the log
209 * @jd: the journal
210 * @head: this is filled in with the log descriptor of the head
211 *
212 * At this point, seg and lh should be either the head of the log or just
213 * before. Scan forward until we find the head.
214 *
215 * Returns: errno
216 */
217
jhead_scan(struct gfs2_jdesc * jd,struct gfs2_log_header_host * head)218 static int jhead_scan(struct gfs2_jdesc *jd, struct gfs2_log_header_host *head)
219 {
220 unsigned int blk = head->lh_blkno;
221 struct gfs2_log_header_host lh;
222 int error;
223
224 for (;;) {
225 if (++blk == jd->jd_blocks)
226 blk = 0;
227
228 error = get_log_header(jd, blk, &lh);
229 if (error < 0)
230 return error;
231 if (error == 1)
232 continue;
233
234 if (lh.lh_sequence == head->lh_sequence) {
235 gfs2_consist_inode(GFS2_I(jd->jd_inode));
236 return -EIO;
237 }
238 if (lh.lh_sequence < head->lh_sequence)
239 break;
240
241 *head = lh;
242 }
243
244 return 0;
245 }
246
247 /**
248 * gfs2_find_jhead - find the head of a log
249 * @jd: the journal
250 * @head: the log descriptor for the head of the log is returned here
251 *
252 * Do a binary search of a journal and find the valid log entry with the
253 * highest sequence number. (i.e. the log head)
254 *
255 * Returns: errno
256 */
257
gfs2_find_jhead(struct gfs2_jdesc * jd,struct gfs2_log_header_host * head)258 int gfs2_find_jhead(struct gfs2_jdesc *jd, struct gfs2_log_header_host *head)
259 {
260 struct gfs2_log_header_host lh_1, lh_m;
261 u32 blk_1, blk_2, blk_m;
262 int error;
263
264 blk_1 = 0;
265 blk_2 = jd->jd_blocks - 1;
266
267 for (;;) {
268 blk_m = (blk_1 + blk_2) / 2;
269
270 error = find_good_lh(jd, &blk_1, &lh_1);
271 if (error)
272 return error;
273
274 error = find_good_lh(jd, &blk_m, &lh_m);
275 if (error)
276 return error;
277
278 if (blk_1 == blk_m || blk_m == blk_2)
279 break;
280
281 if (lh_1.lh_sequence <= lh_m.lh_sequence)
282 blk_1 = blk_m;
283 else
284 blk_2 = blk_m;
285 }
286
287 error = jhead_scan(jd, &lh_1);
288 if (error)
289 return error;
290
291 *head = lh_1;
292
293 return error;
294 }
295
296 /**
297 * foreach_descriptor - go through the active part of the log
298 * @jd: the journal
299 * @start: the first log header in the active region
300 * @end: the last log header (don't process the contents of this entry))
301 *
302 * Call a given function once for every log descriptor in the active
303 * portion of the log.
304 *
305 * Returns: errno
306 */
307
foreach_descriptor(struct gfs2_jdesc * jd,unsigned int start,unsigned int end,int pass)308 static int foreach_descriptor(struct gfs2_jdesc *jd, unsigned int start,
309 unsigned int end, int pass)
310 {
311 struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
312 struct buffer_head *bh;
313 struct gfs2_log_descriptor *ld;
314 int error = 0;
315 u32 length;
316 __be64 *ptr;
317 unsigned int offset = sizeof(struct gfs2_log_descriptor);
318 offset += sizeof(__be64) - 1;
319 offset &= ~(sizeof(__be64) - 1);
320
321 while (start != end) {
322 error = gfs2_replay_read_block(jd, start, &bh);
323 if (error)
324 return error;
325 if (gfs2_meta_check(sdp, bh)) {
326 brelse(bh);
327 return -EIO;
328 }
329 ld = (struct gfs2_log_descriptor *)bh->b_data;
330 length = be32_to_cpu(ld->ld_length);
331
332 if (be32_to_cpu(ld->ld_header.mh_type) == GFS2_METATYPE_LH) {
333 struct gfs2_log_header_host lh;
334 error = get_log_header(jd, start, &lh);
335 if (!error) {
336 gfs2_replay_incr_blk(jd, &start);
337 brelse(bh);
338 continue;
339 }
340 if (error == 1) {
341 gfs2_consist_inode(GFS2_I(jd->jd_inode));
342 error = -EIO;
343 }
344 brelse(bh);
345 return error;
346 } else if (gfs2_metatype_check(sdp, bh, GFS2_METATYPE_LD)) {
347 brelse(bh);
348 return -EIO;
349 }
350 ptr = (__be64 *)(bh->b_data + offset);
351 error = lops_scan_elements(jd, start, ld, ptr, pass);
352 if (error) {
353 brelse(bh);
354 return error;
355 }
356
357 while (length--)
358 gfs2_replay_incr_blk(jd, &start);
359
360 brelse(bh);
361 }
362
363 return 0;
364 }
365
366 /**
367 * clean_journal - mark a dirty journal as being clean
368 * @jd: the journal
369 * @head: the head journal to start from
370 *
371 * Returns: errno
372 */
373
clean_journal(struct gfs2_jdesc * jd,struct gfs2_log_header_host * head)374 static void clean_journal(struct gfs2_jdesc *jd,
375 struct gfs2_log_header_host *head)
376 {
377 struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
378
379 sdp->sd_log_flush_head = head->lh_blkno;
380 gfs2_replay_incr_blk(jd, &sdp->sd_log_flush_head);
381 gfs2_write_log_header(sdp, jd, head->lh_sequence + 1, 0,
382 GFS2_LOG_HEAD_UNMOUNT | GFS2_LOG_HEAD_RECOVERY,
383 REQ_PREFLUSH | REQ_FUA | REQ_META | REQ_SYNC);
384 }
385
386
gfs2_recovery_done(struct gfs2_sbd * sdp,unsigned int jid,unsigned int message)387 static void gfs2_recovery_done(struct gfs2_sbd *sdp, unsigned int jid,
388 unsigned int message)
389 {
390 char env_jid[20];
391 char env_status[20];
392 char *envp[] = { env_jid, env_status, NULL };
393 struct lm_lockstruct *ls = &sdp->sd_lockstruct;
394
395 ls->ls_recover_jid_done = jid;
396 ls->ls_recover_jid_status = message;
397 sprintf(env_jid, "JID=%u", jid);
398 sprintf(env_status, "RECOVERY=%s",
399 message == LM_RD_SUCCESS ? "Done" : "Failed");
400 kobject_uevent_env(&sdp->sd_kobj, KOBJ_CHANGE, envp);
401
402 if (sdp->sd_lockstruct.ls_ops->lm_recovery_result)
403 sdp->sd_lockstruct.ls_ops->lm_recovery_result(sdp, jid, message);
404 }
405
gfs2_recover_func(struct work_struct * work)406 void gfs2_recover_func(struct work_struct *work)
407 {
408 struct gfs2_jdesc *jd = container_of(work, struct gfs2_jdesc, jd_work);
409 struct gfs2_inode *ip = GFS2_I(jd->jd_inode);
410 struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
411 struct gfs2_log_header_host head;
412 struct gfs2_holder j_gh, ji_gh, thaw_gh;
413 ktime_t t_start, t_jlck, t_jhd, t_tlck, t_rep;
414 int ro = 0;
415 unsigned int pass;
416 int error = 0;
417 int jlocked = 0;
418
419 t_start = ktime_get();
420 if (sdp->sd_args.ar_spectator)
421 goto fail;
422 if (jd->jd_jid != sdp->sd_lockstruct.ls_jid) {
423 fs_info(sdp, "jid=%u: Trying to acquire journal lock...\n",
424 jd->jd_jid);
425 jlocked = 1;
426 /* Acquire the journal lock so we can do recovery */
427
428 error = gfs2_glock_nq_num(sdp, jd->jd_jid, &gfs2_journal_glops,
429 LM_ST_EXCLUSIVE,
430 LM_FLAG_NOEXP | LM_FLAG_TRY | GL_NOCACHE,
431 &j_gh);
432 switch (error) {
433 case 0:
434 break;
435
436 case GLR_TRYFAILED:
437 fs_info(sdp, "jid=%u: Busy\n", jd->jd_jid);
438 error = 0;
439
440 default:
441 goto fail;
442 };
443
444 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED,
445 LM_FLAG_NOEXP | GL_NOCACHE, &ji_gh);
446 if (error)
447 goto fail_gunlock_j;
448 } else {
449 fs_info(sdp, "jid=%u, already locked for use\n", jd->jd_jid);
450 }
451
452 t_jlck = ktime_get();
453 fs_info(sdp, "jid=%u: Looking at journal...\n", jd->jd_jid);
454
455 error = gfs2_jdesc_check(jd);
456 if (error)
457 goto fail_gunlock_ji;
458
459 error = gfs2_find_jhead(jd, &head);
460 if (error)
461 goto fail_gunlock_ji;
462 t_jhd = ktime_get();
463
464 if (!(head.lh_flags & GFS2_LOG_HEAD_UNMOUNT)) {
465 fs_info(sdp, "jid=%u: Acquiring the transaction lock...\n",
466 jd->jd_jid);
467
468 /* Acquire a shared hold on the freeze lock */
469
470 error = gfs2_glock_nq_init(sdp->sd_freeze_gl, LM_ST_SHARED,
471 LM_FLAG_NOEXP | LM_FLAG_PRIORITY,
472 &thaw_gh);
473 if (error)
474 goto fail_gunlock_ji;
475
476 if (test_bit(SDF_RORECOVERY, &sdp->sd_flags)) {
477 ro = 1;
478 } else if (test_bit(SDF_JOURNAL_CHECKED, &sdp->sd_flags)) {
479 if (!test_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags))
480 ro = 1;
481 } else {
482 if (sb_rdonly(sdp->sd_vfs)) {
483 /* check if device itself is read-only */
484 ro = bdev_read_only(sdp->sd_vfs->s_bdev);
485 if (!ro) {
486 fs_info(sdp, "recovery required on "
487 "read-only filesystem.\n");
488 fs_info(sdp, "write access will be "
489 "enabled during recovery.\n");
490 }
491 }
492 }
493
494 if (ro) {
495 fs_warn(sdp, "jid=%u: Can't replay: read-only block "
496 "device\n", jd->jd_jid);
497 error = -EROFS;
498 goto fail_gunlock_thaw;
499 }
500
501 t_tlck = ktime_get();
502 fs_info(sdp, "jid=%u: Replaying journal...\n", jd->jd_jid);
503
504 for (pass = 0; pass < 2; pass++) {
505 lops_before_scan(jd, &head, pass);
506 error = foreach_descriptor(jd, head.lh_tail,
507 head.lh_blkno, pass);
508 lops_after_scan(jd, error, pass);
509 if (error)
510 goto fail_gunlock_thaw;
511 }
512
513 clean_journal(jd, &head);
514
515 gfs2_glock_dq_uninit(&thaw_gh);
516 t_rep = ktime_get();
517 fs_info(sdp, "jid=%u: Journal replayed in %lldms [jlck:%lldms, "
518 "jhead:%lldms, tlck:%lldms, replay:%lldms]\n",
519 jd->jd_jid, ktime_ms_delta(t_rep, t_start),
520 ktime_ms_delta(t_jlck, t_start),
521 ktime_ms_delta(t_jhd, t_jlck),
522 ktime_ms_delta(t_tlck, t_jhd),
523 ktime_ms_delta(t_rep, t_tlck));
524 }
525
526 gfs2_recovery_done(sdp, jd->jd_jid, LM_RD_SUCCESS);
527
528 if (jlocked) {
529 gfs2_glock_dq_uninit(&ji_gh);
530 gfs2_glock_dq_uninit(&j_gh);
531 }
532
533 fs_info(sdp, "jid=%u: Done\n", jd->jd_jid);
534 goto done;
535
536 fail_gunlock_thaw:
537 gfs2_glock_dq_uninit(&thaw_gh);
538 fail_gunlock_ji:
539 if (jlocked) {
540 gfs2_glock_dq_uninit(&ji_gh);
541 fail_gunlock_j:
542 gfs2_glock_dq_uninit(&j_gh);
543 }
544
545 fs_info(sdp, "jid=%u: %s\n", jd->jd_jid, (error) ? "Failed" : "Done");
546 fail:
547 jd->jd_recover_error = error;
548 gfs2_recovery_done(sdp, jd->jd_jid, LM_RD_GAVEUP);
549 done:
550 clear_bit(JDF_RECOVERY, &jd->jd_flags);
551 smp_mb__after_atomic();
552 wake_up_bit(&jd->jd_flags, JDF_RECOVERY);
553 }
554
gfs2_recover_journal(struct gfs2_jdesc * jd,bool wait)555 int gfs2_recover_journal(struct gfs2_jdesc *jd, bool wait)
556 {
557 int rv;
558
559 if (test_and_set_bit(JDF_RECOVERY, &jd->jd_flags))
560 return -EBUSY;
561
562 /* we have JDF_RECOVERY, queue should always succeed */
563 rv = queue_work(gfs_recovery_wq, &jd->jd_work);
564 BUG_ON(!rv);
565
566 if (wait)
567 wait_on_bit(&jd->jd_flags, JDF_RECOVERY,
568 TASK_UNINTERRUPTIBLE);
569
570 return wait ? jd->jd_recover_error : 0;
571 }
572
573