xref: /openbmc/linux/fs/gfs2/recovery.c (revision d6b412c5)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
4  * Copyright (C) 2004-2006 Red Hat, Inc.  All rights reserved.
5  */
6 
7 #include <linux/module.h>
8 #include <linux/slab.h>
9 #include <linux/spinlock.h>
10 #include <linux/completion.h>
11 #include <linux/buffer_head.h>
12 #include <linux/gfs2_ondisk.h>
13 #include <linux/crc32.h>
14 #include <linux/crc32c.h>
15 #include <linux/ktime.h>
16 
17 #include "gfs2.h"
18 #include "incore.h"
19 #include "bmap.h"
20 #include "glock.h"
21 #include "glops.h"
22 #include "log.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 *gfs2_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 	u64 dblock;
38 	u32 extlen;
39 	int error;
40 
41 	extlen = 32;
42 	error = gfs2_get_extent(&ip->i_inode, blk, &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_jdesc * jd,u64 blkno,unsigned int where)55 int gfs2_revoke_add(struct gfs2_jdesc *jd, u64 blkno, unsigned int where)
56 {
57 	struct list_head *head = &jd->jd_revoke_list;
58 	struct gfs2_revoke_replay *rr = NULL, *iter;
59 
60 	list_for_each_entry(iter, head, rr_list) {
61 		if (iter->rr_blkno == blkno) {
62 			rr = iter;
63 			break;
64 		}
65 	}
66 
67 	if (rr) {
68 		rr->rr_where = where;
69 		return 0;
70 	}
71 
72 	rr = kmalloc(sizeof(struct gfs2_revoke_replay), GFP_NOFS);
73 	if (!rr)
74 		return -ENOMEM;
75 
76 	rr->rr_blkno = blkno;
77 	rr->rr_where = where;
78 	list_add(&rr->rr_list, head);
79 
80 	return 1;
81 }
82 
gfs2_revoke_check(struct gfs2_jdesc * jd,u64 blkno,unsigned int where)83 int gfs2_revoke_check(struct gfs2_jdesc *jd, u64 blkno, unsigned int where)
84 {
85 	struct gfs2_revoke_replay *rr = NULL, *iter;
86 	int wrap, a, b, revoke;
87 
88 	list_for_each_entry(iter, &jd->jd_revoke_list, rr_list) {
89 		if (iter->rr_blkno == blkno) {
90 			rr = iter;
91 			break;
92 		}
93 	}
94 
95 	if (!rr)
96 		return 0;
97 
98 	wrap = (rr->rr_where < jd->jd_replay_tail);
99 	a = (jd->jd_replay_tail < where);
100 	b = (where < rr->rr_where);
101 	revoke = (wrap) ? (a || b) : (a && b);
102 
103 	return revoke;
104 }
105 
gfs2_revoke_clean(struct gfs2_jdesc * jd)106 void gfs2_revoke_clean(struct gfs2_jdesc *jd)
107 {
108 	struct list_head *head = &jd->jd_revoke_list;
109 	struct gfs2_revoke_replay *rr;
110 
111 	while (!list_empty(head)) {
112 		rr = list_first_entry(head, struct gfs2_revoke_replay, rr_list);
113 		list_del(&rr->rr_list);
114 		kfree(rr);
115 	}
116 }
117 
__get_log_header(struct gfs2_sbd * sdp,const struct gfs2_log_header * lh,unsigned int blkno,struct gfs2_log_header_host * head)118 int __get_log_header(struct gfs2_sbd *sdp, const struct gfs2_log_header *lh,
119 		     unsigned int blkno, struct gfs2_log_header_host *head)
120 {
121 	u32 hash, crc;
122 
123 	if (lh->lh_header.mh_magic != cpu_to_be32(GFS2_MAGIC) ||
124 	    lh->lh_header.mh_type != cpu_to_be32(GFS2_METATYPE_LH) ||
125 	    (blkno && be32_to_cpu(lh->lh_blkno) != blkno))
126 		return 1;
127 
128 	hash = crc32(~0, lh, LH_V1_SIZE - 4);
129 	hash = ~crc32_le_shift(hash, 4); /* assume lh_hash is zero */
130 
131 	if (be32_to_cpu(lh->lh_hash) != hash)
132 		return 1;
133 
134 	crc = crc32c(~0, (void *)lh + LH_V1_SIZE + 4,
135 		     sdp->sd_sb.sb_bsize - LH_V1_SIZE - 4);
136 
137 	if ((lh->lh_crc != 0 && be32_to_cpu(lh->lh_crc) != crc))
138 		return 1;
139 
140 	head->lh_sequence = be64_to_cpu(lh->lh_sequence);
141 	head->lh_flags = be32_to_cpu(lh->lh_flags);
142 	head->lh_tail = be32_to_cpu(lh->lh_tail);
143 	head->lh_blkno = be32_to_cpu(lh->lh_blkno);
144 
145 	head->lh_local_total = be64_to_cpu(lh->lh_local_total);
146 	head->lh_local_free = be64_to_cpu(lh->lh_local_free);
147 	head->lh_local_dinodes = be64_to_cpu(lh->lh_local_dinodes);
148 
149 	return 0;
150 }
151 /**
152  * get_log_header - read the log header for a given segment
153  * @jd: the journal
154  * @blk: the block to look at
155  * @head: the log header to return
156  *
157  * Read the log header for a given segement in a given journal.  Do a few
158  * sanity checks on it.
159  *
160  * Returns: 0 on success,
161  *          1 if the header was invalid or incomplete,
162  *          errno on error
163  */
164 
get_log_header(struct gfs2_jdesc * jd,unsigned int blk,struct gfs2_log_header_host * head)165 static int get_log_header(struct gfs2_jdesc *jd, unsigned int blk,
166 			  struct gfs2_log_header_host *head)
167 {
168 	struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
169 	struct buffer_head *bh;
170 	int error;
171 
172 	error = gfs2_replay_read_block(jd, blk, &bh);
173 	if (error)
174 		return error;
175 
176 	error = __get_log_header(sdp, (const struct gfs2_log_header *)bh->b_data,
177 				 blk, head);
178 	brelse(bh);
179 
180 	return error;
181 }
182 
183 /**
184  * foreach_descriptor - go through the active part of the log
185  * @jd: the journal
186  * @start: the first log header in the active region
187  * @end: the last log header (don't process the contents of this entry))
188  * @pass: iteration number (foreach_descriptor() is called in a for() loop)
189  *
190  * Call a given function once for every log descriptor in the active
191  * portion of the log.
192  *
193  * Returns: errno
194  */
195 
foreach_descriptor(struct gfs2_jdesc * jd,u32 start,unsigned int end,int pass)196 static int foreach_descriptor(struct gfs2_jdesc *jd, u32 start,
197 			      unsigned int end, int pass)
198 {
199 	struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
200 	struct buffer_head *bh;
201 	struct gfs2_log_descriptor *ld;
202 	int error = 0;
203 	u32 length;
204 	__be64 *ptr;
205 	unsigned int offset = sizeof(struct gfs2_log_descriptor);
206 	offset += sizeof(__be64) - 1;
207 	offset &= ~(sizeof(__be64) - 1);
208 
209 	while (start != end) {
210 		error = gfs2_replay_read_block(jd, start, &bh);
211 		if (error)
212 			return error;
213 		if (gfs2_meta_check(sdp, bh)) {
214 			brelse(bh);
215 			return -EIO;
216 		}
217 		ld = (struct gfs2_log_descriptor *)bh->b_data;
218 		length = be32_to_cpu(ld->ld_length);
219 
220 		if (be32_to_cpu(ld->ld_header.mh_type) == GFS2_METATYPE_LH) {
221 			struct gfs2_log_header_host lh;
222 			error = get_log_header(jd, start, &lh);
223 			if (!error) {
224 				gfs2_replay_incr_blk(jd, &start);
225 				brelse(bh);
226 				continue;
227 			}
228 			if (error == 1) {
229 				gfs2_consist_inode(GFS2_I(jd->jd_inode));
230 				error = -EIO;
231 			}
232 			brelse(bh);
233 			return error;
234 		} else if (gfs2_metatype_check(sdp, bh, GFS2_METATYPE_LD)) {
235 			brelse(bh);
236 			return -EIO;
237 		}
238 		ptr = (__be64 *)(bh->b_data + offset);
239 		error = lops_scan_elements(jd, start, ld, ptr, pass);
240 		if (error) {
241 			brelse(bh);
242 			return error;
243 		}
244 
245 		while (length--)
246 			gfs2_replay_incr_blk(jd, &start);
247 
248 		brelse(bh);
249 	}
250 
251 	return 0;
252 }
253 
254 /**
255  * clean_journal - mark a dirty journal as being clean
256  * @jd: the journal
257  * @head: the head journal to start from
258  *
259  * Returns: errno
260  */
261 
clean_journal(struct gfs2_jdesc * jd,struct gfs2_log_header_host * head)262 static void clean_journal(struct gfs2_jdesc *jd,
263 			  struct gfs2_log_header_host *head)
264 {
265 	struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
266 	u32 lblock = head->lh_blkno;
267 
268 	gfs2_replay_incr_blk(jd, &lblock);
269 	gfs2_write_log_header(sdp, jd, head->lh_sequence + 1, 0, lblock,
270 			      GFS2_LOG_HEAD_UNMOUNT | GFS2_LOG_HEAD_RECOVERY,
271 			      REQ_PREFLUSH | REQ_FUA | REQ_META | REQ_SYNC);
272 	if (jd->jd_jid == sdp->sd_lockstruct.ls_jid) {
273 		sdp->sd_log_flush_head = lblock;
274 		gfs2_log_incr_head(sdp);
275 	}
276 }
277 
278 
gfs2_recovery_done(struct gfs2_sbd * sdp,unsigned int jid,unsigned int message)279 static void gfs2_recovery_done(struct gfs2_sbd *sdp, unsigned int jid,
280                                unsigned int message)
281 {
282 	char env_jid[20];
283 	char env_status[20];
284 	char *envp[] = { env_jid, env_status, NULL };
285 	struct lm_lockstruct *ls = &sdp->sd_lockstruct;
286 
287         ls->ls_recover_jid_done = jid;
288         ls->ls_recover_jid_status = message;
289 	sprintf(env_jid, "JID=%u", jid);
290 	sprintf(env_status, "RECOVERY=%s",
291 		message == LM_RD_SUCCESS ? "Done" : "Failed");
292         kobject_uevent_env(&sdp->sd_kobj, KOBJ_CHANGE, envp);
293 
294 	if (sdp->sd_lockstruct.ls_ops->lm_recovery_result)
295 		sdp->sd_lockstruct.ls_ops->lm_recovery_result(sdp, jid, message);
296 }
297 
298 /**
299  * update_statfs_inode - Update the master statfs inode or zero out the local
300  *			 statfs inode for a given journal.
301  * @jd: The journal
302  * @head: If NULL, @inode is the local statfs inode and we need to zero it out.
303  *	  Otherwise, it @head contains the statfs change info that needs to be
304  *	  synced to the master statfs inode (pointed to by @inode).
305  * @inode: statfs inode to update.
306  */
update_statfs_inode(struct gfs2_jdesc * jd,struct gfs2_log_header_host * head,struct inode * inode)307 static int update_statfs_inode(struct gfs2_jdesc *jd,
308 			       struct gfs2_log_header_host *head,
309 			       struct inode *inode)
310 {
311 	struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
312 	struct gfs2_inode *ip;
313 	struct buffer_head *bh;
314 	struct gfs2_statfs_change_host sc;
315 	int error = 0;
316 
317 	BUG_ON(!inode);
318 	ip = GFS2_I(inode);
319 
320 	error = gfs2_meta_inode_buffer(ip, &bh);
321 	if (error)
322 		goto out;
323 
324 	spin_lock(&sdp->sd_statfs_spin);
325 
326 	if (head) { /* Update the master statfs inode */
327 		gfs2_statfs_change_in(&sc, bh->b_data + sizeof(struct gfs2_dinode));
328 		sc.sc_total += head->lh_local_total;
329 		sc.sc_free += head->lh_local_free;
330 		sc.sc_dinodes += head->lh_local_dinodes;
331 		gfs2_statfs_change_out(&sc, bh->b_data + sizeof(struct gfs2_dinode));
332 
333 		fs_info(sdp, "jid=%u: Updated master statfs Total:%lld, "
334 			"Free:%lld, Dinodes:%lld after change "
335 			"[%+lld,%+lld,%+lld]\n", jd->jd_jid, sc.sc_total,
336 			sc.sc_free, sc.sc_dinodes, head->lh_local_total,
337 			head->lh_local_free, head->lh_local_dinodes);
338 	} else { /* Zero out the local statfs inode */
339 		memset(bh->b_data + sizeof(struct gfs2_dinode), 0,
340 		       sizeof(struct gfs2_statfs_change));
341 		/* If it's our own journal, reset any in-memory changes too */
342 		if (jd->jd_jid == sdp->sd_lockstruct.ls_jid) {
343 			memset(&sdp->sd_statfs_local, 0,
344 			       sizeof(struct gfs2_statfs_change_host));
345 		}
346 	}
347 	spin_unlock(&sdp->sd_statfs_spin);
348 
349 	mark_buffer_dirty(bh);
350 	brelse(bh);
351 	gfs2_inode_metasync(ip->i_gl);
352 
353 out:
354 	return error;
355 }
356 
357 /**
358  * recover_local_statfs - Update the master and local statfs changes for this
359  *			  journal.
360  *
361  * Previously, statfs updates would be read in from the local statfs inode and
362  * synced to the master statfs inode during recovery.
363  *
364  * We now use the statfs updates in the journal head to update the master statfs
365  * inode instead of reading in from the local statfs inode. To preserve backward
366  * compatibility with kernels that can't do this, we still need to keep the
367  * local statfs inode up to date by writing changes to it. At some point in the
368  * future, we can do away with the local statfs inodes altogether and keep the
369  * statfs changes solely in the journal.
370  *
371  * @jd: the journal
372  * @head: the journal head
373  *
374  * Returns: errno
375  */
recover_local_statfs(struct gfs2_jdesc * jd,struct gfs2_log_header_host * head)376 static void recover_local_statfs(struct gfs2_jdesc *jd,
377 				 struct gfs2_log_header_host *head)
378 {
379 	int error;
380 	struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
381 
382 	if (!head->lh_local_total && !head->lh_local_free
383 	    && !head->lh_local_dinodes) /* No change */
384 		goto zero_local;
385 
386 	 /* First update the master statfs inode with the changes we
387 	  * found in the journal. */
388 	error = update_statfs_inode(jd, head, sdp->sd_statfs_inode);
389 	if (error)
390 		goto out;
391 
392 zero_local:
393 	/* Zero out the local statfs inode so any changes in there
394 	 * are not re-recovered. */
395 	error = update_statfs_inode(jd, NULL,
396 				    find_local_statfs_inode(sdp, jd->jd_jid));
397 out:
398 	return;
399 }
400 
gfs2_recover_func(struct work_struct * work)401 void gfs2_recover_func(struct work_struct *work)
402 {
403 	struct gfs2_jdesc *jd = container_of(work, struct gfs2_jdesc, jd_work);
404 	struct gfs2_inode *ip = GFS2_I(jd->jd_inode);
405 	struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
406 	struct gfs2_log_header_host head;
407 	struct gfs2_holder j_gh, ji_gh;
408 	ktime_t t_start, t_jlck, t_jhd, t_tlck, t_rep;
409 	int ro = 0;
410 	unsigned int pass;
411 	int error = 0;
412 	int jlocked = 0;
413 
414 	if (gfs2_withdrawing_or_withdrawn(sdp)) {
415 		fs_err(sdp, "jid=%u: Recovery not attempted due to withdraw.\n",
416 		       jd->jd_jid);
417 		goto fail;
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 glock...\n",
424 			jd->jd_jid);
425 		jlocked = 1;
426 		/* Acquire the journal glock 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 			goto fail;
440 
441 		default:
442 			goto fail;
443 		}
444 
445 		error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED,
446 					   LM_FLAG_NOEXP | GL_NOCACHE, &ji_gh);
447 		if (error)
448 			goto fail_gunlock_j;
449 	} else {
450 		fs_info(sdp, "jid=%u, already locked for use\n", jd->jd_jid);
451 	}
452 
453 	t_jlck = ktime_get();
454 	fs_info(sdp, "jid=%u: Looking at journal...\n", jd->jd_jid);
455 
456 	error = gfs2_jdesc_check(jd);
457 	if (error)
458 		goto fail_gunlock_ji;
459 
460 	error = gfs2_find_jhead(jd, &head, true);
461 	if (error)
462 		goto fail_gunlock_ji;
463 	t_jhd = ktime_get();
464 	fs_info(sdp, "jid=%u: Journal head lookup took %lldms\n", jd->jd_jid,
465 		ktime_ms_delta(t_jhd, t_jlck));
466 
467 	if (!(head.lh_flags & GFS2_LOG_HEAD_UNMOUNT)) {
468 		mutex_lock(&sdp->sd_freeze_mutex);
469 
470 		if (test_bit(SDF_FROZEN, &sdp->sd_flags)) {
471 			mutex_unlock(&sdp->sd_freeze_mutex);
472 			fs_warn(sdp, "jid=%u: Can't replay: filesystem "
473 				"is frozen\n", jd->jd_jid);
474 			goto fail_gunlock_ji;
475 		}
476 
477 		if (test_bit(SDF_RORECOVERY, &sdp->sd_flags)) {
478 			ro = 1;
479 		} else if (test_bit(SDF_JOURNAL_CHECKED, &sdp->sd_flags)) {
480 			if (!test_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags))
481 				ro = 1;
482 		} else {
483 			if (sb_rdonly(sdp->sd_vfs)) {
484 				/* check if device itself is read-only */
485 				ro = bdev_read_only(sdp->sd_vfs->s_bdev);
486 				if (!ro) {
487 					fs_info(sdp, "recovery required on "
488 						"read-only filesystem.\n");
489 					fs_info(sdp, "write access will be "
490 						"enabled during recovery.\n");
491 				}
492 			}
493 		}
494 
495 		if (ro) {
496 			fs_warn(sdp, "jid=%u: Can't replay: read-only block "
497 				"device\n", jd->jd_jid);
498 			error = -EROFS;
499 			goto fail_gunlock_nofreeze;
500 		}
501 
502 		t_tlck = ktime_get();
503 		fs_info(sdp, "jid=%u: Replaying journal...0x%x to 0x%x\n",
504 			jd->jd_jid, head.lh_tail, head.lh_blkno);
505 
506 		/* We take the sd_log_flush_lock here primarily to prevent log
507 		 * flushes and simultaneous journal replays from stomping on
508 		 * each other wrt jd_log_bio. */
509 		down_read(&sdp->sd_log_flush_lock);
510 		for (pass = 0; pass < 2; pass++) {
511 			lops_before_scan(jd, &head, pass);
512 			error = foreach_descriptor(jd, head.lh_tail,
513 						   head.lh_blkno, pass);
514 			lops_after_scan(jd, error, pass);
515 			if (error) {
516 				up_read(&sdp->sd_log_flush_lock);
517 				goto fail_gunlock_nofreeze;
518 			}
519 		}
520 
521 		recover_local_statfs(jd, &head);
522 		clean_journal(jd, &head);
523 		up_read(&sdp->sd_log_flush_lock);
524 
525 		mutex_unlock(&sdp->sd_freeze_mutex);
526 		t_rep = ktime_get();
527 		fs_info(sdp, "jid=%u: Journal replayed in %lldms [jlck:%lldms, "
528 			"jhead:%lldms, tlck:%lldms, replay:%lldms]\n",
529 			jd->jd_jid, ktime_ms_delta(t_rep, t_start),
530 			ktime_ms_delta(t_jlck, t_start),
531 			ktime_ms_delta(t_jhd, t_jlck),
532 			ktime_ms_delta(t_tlck, t_jhd),
533 			ktime_ms_delta(t_rep, t_tlck));
534 	}
535 
536 	gfs2_recovery_done(sdp, jd->jd_jid, LM_RD_SUCCESS);
537 
538 	if (jlocked) {
539 		gfs2_glock_dq_uninit(&ji_gh);
540 		gfs2_glock_dq_uninit(&j_gh);
541 	}
542 
543 	fs_info(sdp, "jid=%u: Done\n", jd->jd_jid);
544 	goto done;
545 
546 fail_gunlock_nofreeze:
547 	mutex_unlock(&sdp->sd_freeze_mutex);
548 fail_gunlock_ji:
549 	if (jlocked) {
550 		gfs2_glock_dq_uninit(&ji_gh);
551 fail_gunlock_j:
552 		gfs2_glock_dq_uninit(&j_gh);
553 	}
554 
555 	fs_info(sdp, "jid=%u: %s\n", jd->jd_jid, (error) ? "Failed" : "Done");
556 fail:
557 	jd->jd_recover_error = error;
558 	gfs2_recovery_done(sdp, jd->jd_jid, LM_RD_GAVEUP);
559 done:
560 	clear_bit(JDF_RECOVERY, &jd->jd_flags);
561 	smp_mb__after_atomic();
562 	wake_up_bit(&jd->jd_flags, JDF_RECOVERY);
563 }
564 
gfs2_recover_journal(struct gfs2_jdesc * jd,bool wait)565 int gfs2_recover_journal(struct gfs2_jdesc *jd, bool wait)
566 {
567 	int rv;
568 
569 	if (test_and_set_bit(JDF_RECOVERY, &jd->jd_flags))
570 		return -EBUSY;
571 
572 	/* we have JDF_RECOVERY, queue should always succeed */
573 	rv = queue_work(gfs2_recovery_wq, &jd->jd_work);
574 	BUG_ON(!rv);
575 
576 	if (wait)
577 		wait_on_bit(&jd->jd_flags, JDF_RECOVERY,
578 			    TASK_UNINTERRUPTIBLE);
579 
580 	return wait ? jd->jd_recover_error : 0;
581 }
582 
583