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
18 #include "gfs2.h"
19 #include "incore.h"
20 #include "bmap.h"
21 #include "glock.h"
22 #include "glops.h"
23 #include "lops.h"
24 #include "meta_io.h"
25 #include "recovery.h"
26 #include "super.h"
27 #include "util.h"
28 #include "dir.h"
29
30 struct workqueue_struct *gfs_recovery_wq;
31
gfs2_replay_read_block(struct gfs2_jdesc * jd,unsigned int blk,struct buffer_head ** bh)32 int gfs2_replay_read_block(struct gfs2_jdesc *jd, unsigned int blk,
33 struct buffer_head **bh)
34 {
35 struct gfs2_inode *ip = GFS2_I(jd->jd_inode);
36 struct gfs2_glock *gl = ip->i_gl;
37 int new = 0;
38 u64 dblock;
39 u32 extlen;
40 int error;
41
42 error = gfs2_extent_map(&ip->i_inode, blk, &new, &dblock, &extlen);
43 if (error)
44 return error;
45 if (!dblock) {
46 gfs2_consist_inode(ip);
47 return -EIO;
48 }
49
50 *bh = gfs2_meta_ra(gl, dblock, extlen);
51
52 return error;
53 }
54
gfs2_revoke_add(struct gfs2_sbd * sdp,u64 blkno,unsigned int where)55 int gfs2_revoke_add(struct gfs2_sbd *sdp, u64 blkno, unsigned int where)
56 {
57 struct list_head *head = &sdp->sd_revoke_list;
58 struct gfs2_revoke_replay *rr;
59 int found = 0;
60
61 list_for_each_entry(rr, head, rr_list) {
62 if (rr->rr_blkno == blkno) {
63 found = 1;
64 break;
65 }
66 }
67
68 if (found) {
69 rr->rr_where = where;
70 return 0;
71 }
72
73 rr = kmalloc(sizeof(struct gfs2_revoke_replay), GFP_NOFS);
74 if (!rr)
75 return -ENOMEM;
76
77 rr->rr_blkno = blkno;
78 rr->rr_where = where;
79 list_add(&rr->rr_list, head);
80
81 return 1;
82 }
83
gfs2_revoke_check(struct gfs2_sbd * sdp,u64 blkno,unsigned int where)84 int gfs2_revoke_check(struct gfs2_sbd *sdp, u64 blkno, unsigned int where)
85 {
86 struct gfs2_revoke_replay *rr;
87 int wrap, a, b, revoke;
88 int found = 0;
89
90 list_for_each_entry(rr, &sdp->sd_revoke_list, rr_list) {
91 if (rr->rr_blkno == blkno) {
92 found = 1;
93 break;
94 }
95 }
96
97 if (!found)
98 return 0;
99
100 wrap = (rr->rr_where < sdp->sd_replay_tail);
101 a = (sdp->sd_replay_tail < where);
102 b = (where < rr->rr_where);
103 revoke = (wrap) ? (a || b) : (a && b);
104
105 return revoke;
106 }
107
gfs2_revoke_clean(struct gfs2_sbd * sdp)108 void gfs2_revoke_clean(struct gfs2_sbd *sdp)
109 {
110 struct list_head *head = &sdp->sd_revoke_list;
111 struct gfs2_revoke_replay *rr;
112
113 while (!list_empty(head)) {
114 rr = list_entry(head->next, struct gfs2_revoke_replay, rr_list);
115 list_del(&rr->rr_list);
116 kfree(rr);
117 }
118 }
119
gfs2_log_header_in(struct gfs2_log_header_host * lh,const void * buf)120 static int gfs2_log_header_in(struct gfs2_log_header_host *lh, const void *buf)
121 {
122 const struct gfs2_log_header *str = buf;
123
124 if (str->lh_header.mh_magic != cpu_to_be32(GFS2_MAGIC) ||
125 str->lh_header.mh_type != cpu_to_be32(GFS2_METATYPE_LH))
126 return 1;
127
128 lh->lh_sequence = be64_to_cpu(str->lh_sequence);
129 lh->lh_flags = be32_to_cpu(str->lh_flags);
130 lh->lh_tail = be32_to_cpu(str->lh_tail);
131 lh->lh_blkno = be32_to_cpu(str->lh_blkno);
132 lh->lh_hash = be32_to_cpu(str->lh_hash);
133 return 0;
134 }
135
136 /**
137 * get_log_header - read the log header for a given segment
138 * @jd: the journal
139 * @blk: the block to look at
140 * @lh: the log header to return
141 *
142 * Read the log header for a given segement in a given journal. Do a few
143 * sanity checks on it.
144 *
145 * Returns: 0 on success,
146 * 1 if the header was invalid or incomplete,
147 * errno on error
148 */
149
get_log_header(struct gfs2_jdesc * jd,unsigned int blk,struct gfs2_log_header_host * head)150 static int get_log_header(struct gfs2_jdesc *jd, unsigned int blk,
151 struct gfs2_log_header_host *head)
152 {
153 struct buffer_head *bh;
154 struct gfs2_log_header_host uninitialized_var(lh);
155 const u32 nothing = 0;
156 u32 hash;
157 int error;
158
159 error = gfs2_replay_read_block(jd, blk, &bh);
160 if (error)
161 return error;
162
163 hash = crc32_le((u32)~0, bh->b_data, sizeof(struct gfs2_log_header) -
164 sizeof(u32));
165 hash = crc32_le(hash, (unsigned char const *)¬hing, sizeof(nothing));
166 hash ^= (u32)~0;
167 error = gfs2_log_header_in(&lh, bh->b_data);
168 brelse(bh);
169
170 if (error || lh.lh_blkno != blk || lh.lh_hash != hash)
171 return 1;
172
173 *head = lh;
174
175 return 0;
176 }
177
178 /**
179 * find_good_lh - find a good log header
180 * @jd: the journal
181 * @blk: the segment to start searching from
182 * @lh: the log header to fill in
183 * @forward: if true search forward in the log, else search backward
184 *
185 * Call get_log_header() to get a log header for a segment, but if the
186 * segment is bad, either scan forward or backward until we find a good one.
187 *
188 * Returns: errno
189 */
190
find_good_lh(struct gfs2_jdesc * jd,unsigned int * blk,struct gfs2_log_header_host * head)191 static int find_good_lh(struct gfs2_jdesc *jd, unsigned int *blk,
192 struct gfs2_log_header_host *head)
193 {
194 unsigned int orig_blk = *blk;
195 int error;
196
197 for (;;) {
198 error = get_log_header(jd, *blk, head);
199 if (error <= 0)
200 return error;
201
202 if (++*blk == jd->jd_blocks)
203 *blk = 0;
204
205 if (*blk == orig_blk) {
206 gfs2_consist_inode(GFS2_I(jd->jd_inode));
207 return -EIO;
208 }
209 }
210 }
211
212 /**
213 * jhead_scan - make sure we've found the head of the log
214 * @jd: the journal
215 * @head: this is filled in with the log descriptor of the head
216 *
217 * At this point, seg and lh should be either the head of the log or just
218 * before. Scan forward until we find the head.
219 *
220 * Returns: errno
221 */
222
jhead_scan(struct gfs2_jdesc * jd,struct gfs2_log_header_host * head)223 static int jhead_scan(struct gfs2_jdesc *jd, struct gfs2_log_header_host *head)
224 {
225 unsigned int blk = head->lh_blkno;
226 struct gfs2_log_header_host lh;
227 int error;
228
229 for (;;) {
230 if (++blk == jd->jd_blocks)
231 blk = 0;
232
233 error = get_log_header(jd, blk, &lh);
234 if (error < 0)
235 return error;
236 if (error == 1)
237 continue;
238
239 if (lh.lh_sequence == head->lh_sequence) {
240 gfs2_consist_inode(GFS2_I(jd->jd_inode));
241 return -EIO;
242 }
243 if (lh.lh_sequence < head->lh_sequence)
244 break;
245
246 *head = lh;
247 }
248
249 return 0;
250 }
251
252 /**
253 * gfs2_find_jhead - find the head of a log
254 * @jd: the journal
255 * @head: the log descriptor for the head of the log is returned here
256 *
257 * Do a binary search of a journal and find the valid log entry with the
258 * highest sequence number. (i.e. the log head)
259 *
260 * Returns: errno
261 */
262
gfs2_find_jhead(struct gfs2_jdesc * jd,struct gfs2_log_header_host * head)263 int gfs2_find_jhead(struct gfs2_jdesc *jd, struct gfs2_log_header_host *head)
264 {
265 struct gfs2_log_header_host lh_1, lh_m;
266 u32 blk_1, blk_2, blk_m;
267 int error;
268
269 blk_1 = 0;
270 blk_2 = jd->jd_blocks - 1;
271
272 for (;;) {
273 blk_m = (blk_1 + blk_2) / 2;
274
275 error = find_good_lh(jd, &blk_1, &lh_1);
276 if (error)
277 return error;
278
279 error = find_good_lh(jd, &blk_m, &lh_m);
280 if (error)
281 return error;
282
283 if (blk_1 == blk_m || blk_m == blk_2)
284 break;
285
286 if (lh_1.lh_sequence <= lh_m.lh_sequence)
287 blk_1 = blk_m;
288 else
289 blk_2 = blk_m;
290 }
291
292 error = jhead_scan(jd, &lh_1);
293 if (error)
294 return error;
295
296 *head = lh_1;
297
298 return error;
299 }
300
301 /**
302 * foreach_descriptor - go through the active part of the log
303 * @jd: the journal
304 * @start: the first log header in the active region
305 * @end: the last log header (don't process the contents of this entry))
306 *
307 * Call a given function once for every log descriptor in the active
308 * portion of the log.
309 *
310 * Returns: errno
311 */
312
foreach_descriptor(struct gfs2_jdesc * jd,unsigned int start,unsigned int end,int pass)313 static int foreach_descriptor(struct gfs2_jdesc *jd, unsigned int start,
314 unsigned int end, int pass)
315 {
316 struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
317 struct buffer_head *bh;
318 struct gfs2_log_descriptor *ld;
319 int error = 0;
320 u32 length;
321 __be64 *ptr;
322 unsigned int offset = sizeof(struct gfs2_log_descriptor);
323 offset += sizeof(__be64) - 1;
324 offset &= ~(sizeof(__be64) - 1);
325
326 while (start != end) {
327 error = gfs2_replay_read_block(jd, start, &bh);
328 if (error)
329 return error;
330 if (gfs2_meta_check(sdp, bh)) {
331 brelse(bh);
332 return -EIO;
333 }
334 ld = (struct gfs2_log_descriptor *)bh->b_data;
335 length = be32_to_cpu(ld->ld_length);
336
337 if (be32_to_cpu(ld->ld_header.mh_type) == GFS2_METATYPE_LH) {
338 struct gfs2_log_header_host lh;
339 error = get_log_header(jd, start, &lh);
340 if (!error) {
341 gfs2_replay_incr_blk(sdp, &start);
342 brelse(bh);
343 continue;
344 }
345 if (error == 1) {
346 gfs2_consist_inode(GFS2_I(jd->jd_inode));
347 error = -EIO;
348 }
349 brelse(bh);
350 return error;
351 } else if (gfs2_metatype_check(sdp, bh, GFS2_METATYPE_LD)) {
352 brelse(bh);
353 return -EIO;
354 }
355 ptr = (__be64 *)(bh->b_data + offset);
356 error = lops_scan_elements(jd, start, ld, ptr, pass);
357 if (error) {
358 brelse(bh);
359 return error;
360 }
361
362 while (length--)
363 gfs2_replay_incr_blk(sdp, &start);
364
365 brelse(bh);
366 }
367
368 return 0;
369 }
370
371 /**
372 * clean_journal - mark a dirty journal as being clean
373 * @sdp: the filesystem
374 * @jd: the journal
375 * @gl: the journal's glock
376 * @head: the head journal to start from
377 *
378 * Returns: errno
379 */
380
clean_journal(struct gfs2_jdesc * jd,struct gfs2_log_header_host * head)381 static int clean_journal(struct gfs2_jdesc *jd, struct gfs2_log_header_host *head)
382 {
383 struct gfs2_inode *ip = GFS2_I(jd->jd_inode);
384 struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
385 unsigned int lblock;
386 struct gfs2_log_header *lh;
387 u32 hash;
388 struct buffer_head *bh;
389 int error;
390 struct buffer_head bh_map = { .b_state = 0, .b_blocknr = 0 };
391
392 lblock = head->lh_blkno;
393 gfs2_replay_incr_blk(sdp, &lblock);
394 bh_map.b_size = 1 << ip->i_inode.i_blkbits;
395 error = gfs2_block_map(&ip->i_inode, lblock, &bh_map, 0);
396 if (error)
397 return error;
398 if (!bh_map.b_blocknr) {
399 gfs2_consist_inode(ip);
400 return -EIO;
401 }
402
403 bh = sb_getblk(sdp->sd_vfs, bh_map.b_blocknr);
404 lock_buffer(bh);
405 memset(bh->b_data, 0, bh->b_size);
406 set_buffer_uptodate(bh);
407 clear_buffer_dirty(bh);
408 unlock_buffer(bh);
409
410 lh = (struct gfs2_log_header *)bh->b_data;
411 memset(lh, 0, sizeof(struct gfs2_log_header));
412 lh->lh_header.mh_magic = cpu_to_be32(GFS2_MAGIC);
413 lh->lh_header.mh_type = cpu_to_be32(GFS2_METATYPE_LH);
414 lh->lh_header.__pad0 = cpu_to_be64(0);
415 lh->lh_header.mh_format = cpu_to_be32(GFS2_FORMAT_LH);
416 lh->lh_header.mh_jid = cpu_to_be32(sdp->sd_jdesc->jd_jid);
417 lh->lh_sequence = cpu_to_be64(head->lh_sequence + 1);
418 lh->lh_flags = cpu_to_be32(GFS2_LOG_HEAD_UNMOUNT);
419 lh->lh_blkno = cpu_to_be32(lblock);
420 hash = gfs2_disk_hash((const char *)lh, sizeof(struct gfs2_log_header));
421 lh->lh_hash = cpu_to_be32(hash);
422
423 set_buffer_dirty(bh);
424 if (sync_dirty_buffer(bh))
425 gfs2_io_error_bh(sdp, bh);
426 brelse(bh);
427
428 return error;
429 }
430
431
gfs2_recovery_done(struct gfs2_sbd * sdp,unsigned int jid,unsigned int message)432 static void gfs2_recovery_done(struct gfs2_sbd *sdp, unsigned int jid,
433 unsigned int message)
434 {
435 char env_jid[20];
436 char env_status[20];
437 char *envp[] = { env_jid, env_status, NULL };
438 struct lm_lockstruct *ls = &sdp->sd_lockstruct;
439
440 ls->ls_recover_jid_done = jid;
441 ls->ls_recover_jid_status = message;
442 sprintf(env_jid, "JID=%d", jid);
443 sprintf(env_status, "RECOVERY=%s",
444 message == LM_RD_SUCCESS ? "Done" : "Failed");
445 kobject_uevent_env(&sdp->sd_kobj, KOBJ_CHANGE, envp);
446
447 if (sdp->sd_lockstruct.ls_ops->lm_recovery_result)
448 sdp->sd_lockstruct.ls_ops->lm_recovery_result(sdp, jid, message);
449 }
450
gfs2_recover_func(struct work_struct * work)451 void gfs2_recover_func(struct work_struct *work)
452 {
453 struct gfs2_jdesc *jd = container_of(work, struct gfs2_jdesc, jd_work);
454 struct gfs2_inode *ip = GFS2_I(jd->jd_inode);
455 struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
456 struct gfs2_log_header_host head;
457 struct gfs2_holder j_gh, ji_gh, t_gh;
458 unsigned long t;
459 int ro = 0;
460 unsigned int pass;
461 int error;
462 int jlocked = 0;
463
464 if (sdp->sd_args.ar_spectator ||
465 (jd->jd_jid != sdp->sd_lockstruct.ls_jid)) {
466 fs_info(sdp, "jid=%u: Trying to acquire journal lock...\n",
467 jd->jd_jid);
468 jlocked = 1;
469 /* Acquire the journal lock so we can do recovery */
470
471 error = gfs2_glock_nq_num(sdp, jd->jd_jid, &gfs2_journal_glops,
472 LM_ST_EXCLUSIVE,
473 LM_FLAG_NOEXP | LM_FLAG_TRY | GL_NOCACHE,
474 &j_gh);
475 switch (error) {
476 case 0:
477 break;
478
479 case GLR_TRYFAILED:
480 fs_info(sdp, "jid=%u: Busy\n", jd->jd_jid);
481 error = 0;
482
483 default:
484 goto fail;
485 };
486
487 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED,
488 LM_FLAG_NOEXP | GL_NOCACHE, &ji_gh);
489 if (error)
490 goto fail_gunlock_j;
491 } else {
492 fs_info(sdp, "jid=%u, already locked for use\n", jd->jd_jid);
493 }
494
495 fs_info(sdp, "jid=%u: Looking at journal...\n", jd->jd_jid);
496
497 error = gfs2_jdesc_check(jd);
498 if (error)
499 goto fail_gunlock_ji;
500
501 error = gfs2_find_jhead(jd, &head);
502 if (error)
503 goto fail_gunlock_ji;
504
505 if (!(head.lh_flags & GFS2_LOG_HEAD_UNMOUNT)) {
506 fs_info(sdp, "jid=%u: Acquiring the transaction lock...\n",
507 jd->jd_jid);
508
509 t = jiffies;
510
511 /* Acquire a shared hold on the transaction lock */
512
513 error = gfs2_glock_nq_init(sdp->sd_trans_gl, LM_ST_SHARED,
514 LM_FLAG_NOEXP | LM_FLAG_PRIORITY |
515 GL_NOCACHE, &t_gh);
516 if (error)
517 goto fail_gunlock_ji;
518
519 if (test_bit(SDF_RORECOVERY, &sdp->sd_flags)) {
520 ro = 1;
521 } else if (test_bit(SDF_JOURNAL_CHECKED, &sdp->sd_flags)) {
522 if (!test_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags))
523 ro = 1;
524 } else {
525 if (sdp->sd_vfs->s_flags & MS_RDONLY) {
526 /* check if device itself is read-only */
527 ro = bdev_read_only(sdp->sd_vfs->s_bdev);
528 if (!ro) {
529 fs_info(sdp, "recovery required on "
530 "read-only filesystem.\n");
531 fs_info(sdp, "write access will be "
532 "enabled during recovery.\n");
533 }
534 }
535 }
536
537 if (ro) {
538 fs_warn(sdp, "jid=%u: Can't replay: read-only block "
539 "device\n", jd->jd_jid);
540 error = -EROFS;
541 goto fail_gunlock_tr;
542 }
543
544 fs_info(sdp, "jid=%u: Replaying journal...\n", jd->jd_jid);
545
546 for (pass = 0; pass < 2; pass++) {
547 lops_before_scan(jd, &head, pass);
548 error = foreach_descriptor(jd, head.lh_tail,
549 head.lh_blkno, pass);
550 lops_after_scan(jd, error, pass);
551 if (error)
552 goto fail_gunlock_tr;
553 }
554
555 error = clean_journal(jd, &head);
556 if (error)
557 goto fail_gunlock_tr;
558
559 gfs2_glock_dq_uninit(&t_gh);
560 t = DIV_ROUND_UP(jiffies - t, HZ);
561 fs_info(sdp, "jid=%u: Journal replayed in %lus\n",
562 jd->jd_jid, t);
563 }
564
565 gfs2_recovery_done(sdp, jd->jd_jid, LM_RD_SUCCESS);
566
567 if (jlocked) {
568 gfs2_glock_dq_uninit(&ji_gh);
569 gfs2_glock_dq_uninit(&j_gh);
570 }
571
572 fs_info(sdp, "jid=%u: Done\n", jd->jd_jid);
573 goto done;
574
575 fail_gunlock_tr:
576 gfs2_glock_dq_uninit(&t_gh);
577 fail_gunlock_ji:
578 if (jlocked) {
579 gfs2_glock_dq_uninit(&ji_gh);
580 fail_gunlock_j:
581 gfs2_glock_dq_uninit(&j_gh);
582 }
583
584 fs_info(sdp, "jid=%u: %s\n", jd->jd_jid, (error) ? "Failed" : "Done");
585 fail:
586 jd->jd_recover_error = error;
587 gfs2_recovery_done(sdp, jd->jd_jid, LM_RD_GAVEUP);
588 done:
589 clear_bit(JDF_RECOVERY, &jd->jd_flags);
590 smp_mb__after_clear_bit();
591 wake_up_bit(&jd->jd_flags, JDF_RECOVERY);
592 }
593
gfs2_recovery_wait(void * word)594 static int gfs2_recovery_wait(void *word)
595 {
596 schedule();
597 return 0;
598 }
599
gfs2_recover_journal(struct gfs2_jdesc * jd,bool wait)600 int gfs2_recover_journal(struct gfs2_jdesc *jd, bool wait)
601 {
602 int rv;
603
604 if (test_and_set_bit(JDF_RECOVERY, &jd->jd_flags))
605 return -EBUSY;
606
607 /* we have JDF_RECOVERY, queue should always succeed */
608 rv = queue_work(gfs_recovery_wq, &jd->jd_work);
609 BUG_ON(!rv);
610
611 if (wait)
612 wait_on_bit(&jd->jd_flags, JDF_RECOVERY, gfs2_recovery_wait,
613 TASK_UNINTERRUPTIBLE);
614
615 return wait ? jd->jd_recover_error : 0;
616 }
617
618