xref: /linux/fs/gfs2/util.c (revision ab93e0dd72c37d378dd936f031ffb83ff2bd87ce)
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 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
8 
9 #include <linux/spinlock.h>
10 #include <linux/completion.h>
11 #include <linux/buffer_head.h>
12 #include <linux/kthread.h>
13 #include <linux/crc32.h>
14 #include <linux/gfs2_ondisk.h>
15 #include <linux/delay.h>
16 #include <linux/uaccess.h>
17 
18 #include "gfs2.h"
19 #include "incore.h"
20 #include "glock.h"
21 #include "glops.h"
22 #include "log.h"
23 #include "lops.h"
24 #include "recovery.h"
25 #include "rgrp.h"
26 #include "super.h"
27 #include "util.h"
28 
29 struct kmem_cache *gfs2_glock_cachep __read_mostly;
30 struct kmem_cache *gfs2_glock_aspace_cachep __read_mostly;
31 struct kmem_cache *gfs2_inode_cachep __read_mostly;
32 struct kmem_cache *gfs2_bufdata_cachep __read_mostly;
33 struct kmem_cache *gfs2_rgrpd_cachep __read_mostly;
34 struct kmem_cache *gfs2_quotad_cachep __read_mostly;
35 struct kmem_cache *gfs2_qadata_cachep __read_mostly;
36 struct kmem_cache *gfs2_trans_cachep __read_mostly;
37 mempool_t *gfs2_page_pool __read_mostly;
38 
gfs2_assert_i(struct gfs2_sbd * sdp)39 void gfs2_assert_i(struct gfs2_sbd *sdp)
40 {
41 	fs_emerg(sdp, "fatal assertion failed\n");
42 }
43 
44 /**
45  * check_journal_clean - Make sure a journal is clean for a spectator mount
46  * @sdp: The GFS2 superblock
47  * @jd: The journal descriptor
48  * @verbose: Show more prints in the log
49  *
50  * Returns: 0 if the journal is clean or locked, else an error
51  */
check_journal_clean(struct gfs2_sbd * sdp,struct gfs2_jdesc * jd,bool verbose)52 int check_journal_clean(struct gfs2_sbd *sdp, struct gfs2_jdesc *jd,
53 			bool verbose)
54 {
55 	int error;
56 	struct gfs2_holder j_gh;
57 	struct gfs2_log_header_host head;
58 	struct gfs2_inode *ip;
59 
60 	ip = GFS2_I(jd->jd_inode);
61 	error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_NOEXP |
62 				   GL_EXACT | GL_NOCACHE, &j_gh);
63 	if (error) {
64 		if (verbose)
65 			fs_err(sdp, "Error %d locking journal for spectator "
66 			       "mount.\n", error);
67 		return -EPERM;
68 	}
69 	error = gfs2_jdesc_check(jd);
70 	if (error) {
71 		if (verbose)
72 			fs_err(sdp, "Error checking journal for spectator "
73 			       "mount.\n");
74 		goto out_unlock;
75 	}
76 	error = gfs2_find_jhead(jd, &head);
77 	if (error) {
78 		if (verbose)
79 			fs_err(sdp, "Error parsing journal for spectator "
80 			       "mount.\n");
81 		goto out_unlock;
82 	}
83 	if (!(head.lh_flags & GFS2_LOG_HEAD_UNMOUNT)) {
84 		error = -EPERM;
85 		if (verbose)
86 			fs_err(sdp, "jid=%u: Journal is dirty, so the first "
87 			       "mounter must not be a spectator.\n",
88 			       jd->jd_jid);
89 	}
90 
91 out_unlock:
92 	gfs2_glock_dq_uninit(&j_gh);
93 	return error;
94 }
95 
96 /**
97  * gfs2_freeze_lock_shared - hold the freeze glock
98  * @sdp: the superblock
99  */
gfs2_freeze_lock_shared(struct gfs2_sbd * sdp)100 int gfs2_freeze_lock_shared(struct gfs2_sbd *sdp)
101 {
102 	int flags = LM_FLAG_NOEXP | GL_EXACT;
103 	int error;
104 
105 	error = gfs2_glock_nq_init(sdp->sd_freeze_gl, LM_ST_SHARED, flags,
106 				   &sdp->sd_freeze_gh);
107 	if (error && error != GLR_TRYFAILED)
108 		fs_err(sdp, "can't lock the freeze glock: %d\n", error);
109 	return error;
110 }
111 
gfs2_freeze_unlock(struct gfs2_sbd * sdp)112 void gfs2_freeze_unlock(struct gfs2_sbd *sdp)
113 {
114 	if (gfs2_holder_initialized(&sdp->sd_freeze_gh))
115 		gfs2_glock_dq_uninit(&sdp->sd_freeze_gh);
116 }
117 
signal_our_withdraw(struct gfs2_sbd * sdp)118 static void signal_our_withdraw(struct gfs2_sbd *sdp)
119 {
120 	struct gfs2_glock *live_gl = sdp->sd_live_gh.gh_gl;
121 	struct inode *inode;
122 	struct gfs2_inode *ip;
123 	struct gfs2_glock *i_gl;
124 	u64 no_formal_ino;
125 	int ret = 0;
126 	int tries;
127 
128 	if (test_bit(SDF_NORECOVERY, &sdp->sd_flags) || !sdp->sd_jdesc)
129 		return;
130 
131 	gfs2_ail_drain(sdp); /* frees all transactions */
132 	inode = sdp->sd_jdesc->jd_inode;
133 	ip = GFS2_I(inode);
134 	i_gl = ip->i_gl;
135 	no_formal_ino = ip->i_no_formal_ino;
136 
137 	/* Prevent any glock dq until withdraw recovery is complete */
138 	set_bit(SDF_WITHDRAW_RECOVERY, &sdp->sd_flags);
139 	/*
140 	 * Don't tell dlm we're bailing until we have no more buffers in the
141 	 * wind. If journal had an IO error, the log code should just purge
142 	 * the outstanding buffers rather than submitting new IO. Making the
143 	 * file system read-only will flush the journal, etc.
144 	 *
145 	 * During a normal unmount, gfs2_make_fs_ro calls gfs2_log_shutdown
146 	 * which clears SDF_JOURNAL_LIVE. In a withdraw, we must not write
147 	 * any UNMOUNT log header, so we can't call gfs2_log_shutdown, and
148 	 * therefore we need to clear SDF_JOURNAL_LIVE manually.
149 	 */
150 	clear_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags);
151 	if (!sb_rdonly(sdp->sd_vfs)) {
152 		bool locked = mutex_trylock(&sdp->sd_freeze_mutex);
153 
154 		wake_up(&sdp->sd_logd_waitq);
155 		wake_up(&sdp->sd_quota_wait);
156 
157 		wait_event_timeout(sdp->sd_log_waitq,
158 				   gfs2_log_is_empty(sdp),
159 				   HZ * 5);
160 
161 		sdp->sd_vfs->s_flags |= SB_RDONLY;
162 
163 		if (locked)
164 			mutex_unlock(&sdp->sd_freeze_mutex);
165 
166 		/*
167 		 * Dequeue any pending non-system glock holders that can no
168 		 * longer be granted because the file system is withdrawn.
169 		 */
170 		gfs2_gl_dq_holders(sdp);
171 	}
172 
173 	if (sdp->sd_lockstruct.ls_ops->lm_lock == NULL) { /* lock_nolock */
174 		if (!ret)
175 			ret = -EIO;
176 		clear_bit(SDF_WITHDRAW_RECOVERY, &sdp->sd_flags);
177 		goto skip_recovery;
178 	}
179 	/*
180 	 * Drop the glock for our journal so another node can recover it.
181 	 */
182 	if (gfs2_holder_initialized(&sdp->sd_journal_gh)) {
183 		gfs2_glock_dq_wait(&sdp->sd_journal_gh);
184 		gfs2_holder_uninit(&sdp->sd_journal_gh);
185 	}
186 	sdp->sd_jinode_gh.gh_flags |= GL_NOCACHE;
187 	gfs2_glock_dq(&sdp->sd_jinode_gh);
188 	gfs2_thaw_freeze_initiator(sdp->sd_vfs);
189 	wait_on_bit(&i_gl->gl_flags, GLF_DEMOTE, TASK_UNINTERRUPTIBLE);
190 
191 	/*
192 	 * holder_uninit to force glock_put, to force dlm to let go
193 	 */
194 	gfs2_holder_uninit(&sdp->sd_jinode_gh);
195 
196 	/*
197 	 * Note: We need to be careful here:
198 	 * Our iput of jd_inode will evict it. The evict will dequeue its
199 	 * glock, but the glock dq will wait for the withdraw unless we have
200 	 * exception code in glock_dq.
201 	 */
202 	iput(inode);
203 	sdp->sd_jdesc->jd_inode = NULL;
204 	/*
205 	 * Wait until the journal inode's glock is freed. This allows try locks
206 	 * on other nodes to be successful, otherwise we remain the owner of
207 	 * the glock as far as dlm is concerned.
208 	 */
209 	if (i_gl->gl_ops->go_unlocked) {
210 		set_bit(GLF_UNLOCKED, &i_gl->gl_flags);
211 		wait_on_bit(&i_gl->gl_flags, GLF_UNLOCKED, TASK_UNINTERRUPTIBLE);
212 	}
213 
214 	/*
215 	 * Dequeue the "live" glock, but keep a reference so it's never freed.
216 	 */
217 	gfs2_glock_hold(live_gl);
218 	gfs2_glock_dq_wait(&sdp->sd_live_gh);
219 	/*
220 	 * We enqueue the "live" glock in EX so that all other nodes
221 	 * get a demote request and act on it. We don't really want the
222 	 * lock in EX, so we send a "try" lock with 1CB to produce a callback.
223 	 */
224 	fs_warn(sdp, "Requesting recovery of jid %d.\n",
225 		sdp->sd_lockstruct.ls_jid);
226 	gfs2_holder_reinit(LM_ST_EXCLUSIVE,
227 			   LM_FLAG_TRY_1CB | LM_FLAG_NOEXP | GL_NOPID,
228 			   &sdp->sd_live_gh);
229 	msleep(GL_GLOCK_MAX_HOLD);
230 	/*
231 	 * This will likely fail in a cluster, but succeed standalone:
232 	 */
233 	ret = gfs2_glock_nq(&sdp->sd_live_gh);
234 
235 	gfs2_glock_put(live_gl); /* drop extra reference we acquired */
236 	clear_bit(SDF_WITHDRAW_RECOVERY, &sdp->sd_flags);
237 
238 	/*
239 	 * If we actually got the "live" lock in EX mode, there are no other
240 	 * nodes available to replay our journal.
241 	 */
242 	if (ret == 0) {
243 		fs_warn(sdp, "No other mounters found.\n");
244 		/*
245 		 * We are about to release the lockspace.  By keeping live_gl
246 		 * locked here, we ensure that the next mounter coming along
247 		 * will be a "first" mounter which will perform recovery.
248 		 */
249 		goto skip_recovery;
250 	}
251 
252 	/*
253 	 * At this point our journal is evicted, so we need to get a new inode
254 	 * for it. Once done, we need to call gfs2_find_jhead which
255 	 * calls gfs2_map_journal_extents to map it for us again.
256 	 *
257 	 * Note that we don't really want it to look up a FREE block. The
258 	 * GFS2_BLKST_FREE simply overrides a block check in gfs2_inode_lookup
259 	 * which would otherwise fail because it requires grabbing an rgrp
260 	 * glock, which would fail with -EIO because we're withdrawing.
261 	 */
262 	inode = gfs2_inode_lookup(sdp->sd_vfs, DT_UNKNOWN,
263 				  sdp->sd_jdesc->jd_no_addr, no_formal_ino,
264 				  GFS2_BLKST_FREE);
265 	if (IS_ERR(inode)) {
266 		fs_warn(sdp, "Reprocessing of jid %d failed with %ld.\n",
267 			sdp->sd_lockstruct.ls_jid, PTR_ERR(inode));
268 		goto skip_recovery;
269 	}
270 	sdp->sd_jdesc->jd_inode = inode;
271 	d_mark_dontcache(inode);
272 
273 	/*
274 	 * Now wait until recovery is complete.
275 	 */
276 	for (tries = 0; tries < 10; tries++) {
277 		ret = check_journal_clean(sdp, sdp->sd_jdesc, false);
278 		if (!ret)
279 			break;
280 		msleep(HZ);
281 		fs_warn(sdp, "Waiting for journal recovery jid %d.\n",
282 			sdp->sd_lockstruct.ls_jid);
283 	}
284 skip_recovery:
285 	if (!ret)
286 		fs_warn(sdp, "Journal recovery complete for jid %d.\n",
287 			sdp->sd_lockstruct.ls_jid);
288 	else
289 		fs_warn(sdp, "Journal recovery skipped for jid %d until next "
290 			"mount.\n", sdp->sd_lockstruct.ls_jid);
291 	fs_warn(sdp, "Glock dequeues delayed: %lu\n", sdp->sd_glock_dqs_held);
292 	sdp->sd_glock_dqs_held = 0;
293 	wake_up_bit(&sdp->sd_flags, SDF_WITHDRAW_RECOVERY);
294 }
295 
gfs2_lm(struct gfs2_sbd * sdp,const char * fmt,...)296 void gfs2_lm(struct gfs2_sbd *sdp, const char *fmt, ...)
297 {
298 	struct va_format vaf;
299 	va_list args;
300 
301 	if (sdp->sd_args.ar_errors == GFS2_ERRORS_WITHDRAW &&
302 	    test_bit(SDF_WITHDRAWN, &sdp->sd_flags))
303 		return;
304 
305 	va_start(args, fmt);
306 	vaf.fmt = fmt;
307 	vaf.va = &args;
308 	fs_err(sdp, "%pV", &vaf);
309 	va_end(args);
310 }
311 
gfs2_withdraw(struct gfs2_sbd * sdp)312 int gfs2_withdraw(struct gfs2_sbd *sdp)
313 {
314 	struct lm_lockstruct *ls = &sdp->sd_lockstruct;
315 	const struct lm_lockops *lm = ls->ls_ops;
316 
317 	if (sdp->sd_args.ar_errors == GFS2_ERRORS_WITHDRAW) {
318 		unsigned long old = READ_ONCE(sdp->sd_flags), new;
319 
320 		do {
321 			if (old & BIT(SDF_WITHDRAWN)) {
322 				wait_on_bit(&sdp->sd_flags,
323 					    SDF_WITHDRAW_IN_PROG,
324 					    TASK_UNINTERRUPTIBLE);
325 				return -1;
326 			}
327 			new = old | BIT(SDF_WITHDRAWN) | BIT(SDF_WITHDRAW_IN_PROG);
328 		} while (unlikely(!try_cmpxchg(&sdp->sd_flags, &old, new)));
329 
330 		fs_err(sdp, "about to withdraw this file system\n");
331 		BUG_ON(sdp->sd_args.ar_debug);
332 
333 		signal_our_withdraw(sdp);
334 
335 		kobject_uevent(&sdp->sd_kobj, KOBJ_OFFLINE);
336 
337 		if (!strcmp(sdp->sd_lockstruct.ls_ops->lm_proto_name, "lock_dlm"))
338 			wait_for_completion(&sdp->sd_wdack);
339 
340 		if (lm->lm_unmount) {
341 			fs_err(sdp, "telling LM to unmount\n");
342 			lm->lm_unmount(sdp);
343 		}
344 		fs_err(sdp, "File system withdrawn\n");
345 		dump_stack();
346 		clear_bit(SDF_WITHDRAW_IN_PROG, &sdp->sd_flags);
347 		smp_mb__after_atomic();
348 		wake_up_bit(&sdp->sd_flags, SDF_WITHDRAW_IN_PROG);
349 	}
350 
351 	if (sdp->sd_args.ar_errors == GFS2_ERRORS_PANIC)
352 		panic("GFS2: fsid=%s: panic requested\n", sdp->sd_fsname);
353 
354 	return -1;
355 }
356 
357 /*
358  * gfs2_assert_withdraw_i - Cause the machine to withdraw if @assertion is false
359  */
360 
gfs2_assert_withdraw_i(struct gfs2_sbd * sdp,char * assertion,const char * function,char * file,unsigned int line,bool delayed)361 void gfs2_assert_withdraw_i(struct gfs2_sbd *sdp, char *assertion,
362 			    const char *function, char *file, unsigned int line,
363 			    bool delayed)
364 {
365 	if (gfs2_withdrawing_or_withdrawn(sdp))
366 		return;
367 
368 	fs_err(sdp,
369 	       "fatal: assertion \"%s\" failed - "
370 	       "function = %s, file = %s, line = %u\n",
371 	       assertion, function, file, line);
372 
373 	/*
374 	 * If errors=panic was specified on mount, it won't help to delay the
375 	 * withdraw.
376 	 */
377 	if (sdp->sd_args.ar_errors == GFS2_ERRORS_PANIC)
378 		delayed = false;
379 
380 	if (delayed)
381 		gfs2_withdraw_delayed(sdp);
382 	else
383 		gfs2_withdraw(sdp);
384 	dump_stack();
385 }
386 
387 /*
388  * gfs2_assert_warn_i - Print a message to the console if @assertion is false
389  */
390 
gfs2_assert_warn_i(struct gfs2_sbd * sdp,char * assertion,const char * function,char * file,unsigned int line)391 void gfs2_assert_warn_i(struct gfs2_sbd *sdp, char *assertion,
392 			const char *function, char *file, unsigned int line)
393 {
394 	if (time_before(jiffies,
395 			sdp->sd_last_warning +
396 			gfs2_tune_get(sdp, gt_complain_secs) * HZ))
397 		return;
398 
399 	if (sdp->sd_args.ar_errors == GFS2_ERRORS_WITHDRAW)
400 		fs_warn(sdp, "warning: assertion \"%s\" failed - "
401 			"function = %s, file = %s, line = %u\n",
402 			assertion, function, file, line);
403 
404 	if (sdp->sd_args.ar_debug)
405 		BUG();
406 	else
407 		dump_stack();
408 
409 	if (sdp->sd_args.ar_errors == GFS2_ERRORS_PANIC)
410 		panic("GFS2: fsid=%s: warning: assertion \"%s\" failed - "
411 		      "function = %s, file = %s, line = %u\n",
412 		      sdp->sd_fsname, assertion,
413 		      function, file, line);
414 
415 	sdp->sd_last_warning = jiffies;
416 }
417 
418 /*
419  * gfs2_consist_i - Flag a filesystem consistency error and withdraw
420  */
421 
gfs2_consist_i(struct gfs2_sbd * sdp,const char * function,char * file,unsigned int line)422 void gfs2_consist_i(struct gfs2_sbd *sdp, const char *function,
423 		    char *file, unsigned int line)
424 {
425 	gfs2_lm(sdp,
426 		"fatal: filesystem consistency error - "
427 		"function = %s, file = %s, line = %u\n",
428 		function, file, line);
429 	gfs2_withdraw(sdp);
430 }
431 
432 /*
433  * gfs2_consist_inode_i - Flag an inode consistency error and withdraw
434  */
435 
gfs2_consist_inode_i(struct gfs2_inode * ip,const char * function,char * file,unsigned int line)436 void gfs2_consist_inode_i(struct gfs2_inode *ip,
437 			  const char *function, char *file, unsigned int line)
438 {
439 	struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
440 
441 	gfs2_lm(sdp,
442 		"fatal: filesystem consistency error - "
443 		"inode = %llu %llu, "
444 		"function = %s, file = %s, line = %u\n",
445 		(unsigned long long)ip->i_no_formal_ino,
446 		(unsigned long long)ip->i_no_addr,
447 		function, file, line);
448 	gfs2_dump_glock(NULL, ip->i_gl, 1);
449 	gfs2_withdraw(sdp);
450 }
451 
452 /*
453  * gfs2_consist_rgrpd_i - Flag a RG consistency error and withdraw
454  */
455 
gfs2_consist_rgrpd_i(struct gfs2_rgrpd * rgd,const char * function,char * file,unsigned int line)456 void gfs2_consist_rgrpd_i(struct gfs2_rgrpd *rgd,
457 			  const char *function, char *file, unsigned int line)
458 {
459 	struct gfs2_sbd *sdp = rgd->rd_sbd;
460 	char fs_id_buf[sizeof(sdp->sd_fsname) + 7];
461 
462 	sprintf(fs_id_buf, "fsid=%s: ", sdp->sd_fsname);
463 	gfs2_rgrp_dump(NULL, rgd, fs_id_buf);
464 	gfs2_lm(sdp,
465 		"fatal: filesystem consistency error - "
466 		"RG = %llu, "
467 		"function = %s, file = %s, line = %u\n",
468 		(unsigned long long)rgd->rd_addr,
469 		function, file, line);
470 	gfs2_dump_glock(NULL, rgd->rd_gl, 1);
471 	gfs2_withdraw(sdp);
472 }
473 
474 /*
475  * gfs2_meta_check_ii - Flag a magic number consistency error and withdraw
476  * Returns: -1 if this call withdrew the machine,
477  *          -2 if it was already withdrawn
478  */
479 
gfs2_meta_check_ii(struct gfs2_sbd * sdp,struct buffer_head * bh,const char * function,char * file,unsigned int line)480 int gfs2_meta_check_ii(struct gfs2_sbd *sdp, struct buffer_head *bh,
481 		       const char *function, char *file,
482 		       unsigned int line)
483 {
484 	int me;
485 
486 	gfs2_lm(sdp,
487 		"fatal: invalid metadata block - "
488 		"bh = %llu (bad magic number), "
489 		"function = %s, file = %s, line = %u\n",
490 		(unsigned long long)bh->b_blocknr,
491 		function, file, line);
492 	me = gfs2_withdraw(sdp);
493 	return (me) ? -1 : -2;
494 }
495 
496 /*
497  * gfs2_metatype_check_ii - Flag a metadata type consistency error and withdraw
498  * Returns: -1 if this call withdrew the machine,
499  *          -2 if it was already withdrawn
500  */
501 
gfs2_metatype_check_ii(struct gfs2_sbd * sdp,struct buffer_head * bh,u16 type,u16 t,const char * function,char * file,unsigned int line)502 int gfs2_metatype_check_ii(struct gfs2_sbd *sdp, struct buffer_head *bh,
503 			   u16 type, u16 t, const char *function,
504 			   char *file, unsigned int line)
505 {
506 	int me;
507 
508 	gfs2_lm(sdp,
509 		"fatal: invalid metadata block - "
510 		"bh = %llu (type: exp=%u, found=%u), "
511 		"function = %s, file = %s, line = %u\n",
512 		(unsigned long long)bh->b_blocknr, type, t,
513 		function, file, line);
514 	me = gfs2_withdraw(sdp);
515 	return (me) ? -1 : -2;
516 }
517 
518 /*
519  * gfs2_io_error_i - Flag an I/O error and withdraw
520  * Returns: -1 if this call withdrew the machine,
521  *          0 if it was already withdrawn
522  */
523 
gfs2_io_error_i(struct gfs2_sbd * sdp,const char * function,char * file,unsigned int line)524 int gfs2_io_error_i(struct gfs2_sbd *sdp, const char *function, char *file,
525 		    unsigned int line)
526 {
527 	gfs2_lm(sdp,
528 		"fatal: I/O error - "
529 		"function = %s, file = %s, line = %u\n",
530 		function, file, line);
531 	return gfs2_withdraw(sdp);
532 }
533 
534 /*
535  * gfs2_io_error_bh_i - Flag a buffer I/O error
536  * @withdraw: withdraw the filesystem
537  */
538 
gfs2_io_error_bh_i(struct gfs2_sbd * sdp,struct buffer_head * bh,const char * function,char * file,unsigned int line,bool withdraw)539 void gfs2_io_error_bh_i(struct gfs2_sbd *sdp, struct buffer_head *bh,
540 			const char *function, char *file, unsigned int line,
541 			bool withdraw)
542 {
543 	if (gfs2_withdrawing_or_withdrawn(sdp))
544 		return;
545 
546 	fs_err(sdp, "fatal: I/O error - "
547 	       "block = %llu, "
548 	       "function = %s, file = %s, line = %u\n",
549 	       (unsigned long long)bh->b_blocknr, function, file, line);
550 	if (withdraw)
551 		gfs2_withdraw(sdp);
552 }
553 
554