summaryrefslogtreecommitdiff
path: root/fs/gfs2/glops.c
blob: d26759a98b1074d417be5ecf2c1c52e934af73fd (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
 * Copyright (C) 2004-2008 Red Hat, Inc.  All rights reserved.
 */

#include <linux/spinlock.h>
#include <linux/completion.h>
#include <linux/buffer_head.h>
#include <linux/gfs2_ondisk.h>
#include <linux/bio.h>
#include <linux/posix_acl.h>
#include <linux/security.h>

#include "gfs2.h"
#include "incore.h"
#include "bmap.h"
#include "glock.h"
#include "glops.h"
#include "inode.h"
#include "log.h"
#include "meta_io.h"
#include "recovery.h"
#include "rgrp.h"
#include "util.h"
#include "trans.h"
#include "dir.h"
#include "lops.h"

struct workqueue_struct *gfs2_freeze_wq;

extern struct workqueue_struct *gfs2_control_wq;

static void gfs2_ail_error(struct gfs2_glock *gl, const struct buffer_head *bh)
{
	struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;

	fs_err(sdp,
	       "AIL buffer %p: blocknr %llu state 0x%08lx mapping %p page "
	       "state 0x%lx\n",
	       bh, (unsigned long long)bh->b_blocknr, bh->b_state,
	       bh->b_folio->mapping, bh->b_folio->flags);
	fs_err(sdp, "AIL glock %u:%llu mapping %p\n",
	       gl->gl_name.ln_type, gl->gl_name.ln_number,
	       gfs2_glock2aspace(gl));
	gfs2_lm(sdp, "AIL error\n");
	gfs2_withdraw_delayed(sdp);
}

/**
 * __gfs2_ail_flush - remove all buffers for a given lock from the AIL
 * @gl: the glock
 * @fsync: set when called from fsync (not all buffers will be clean)
 * @nr_revokes: Number of buffers to revoke
 *
 * None of the buffers should be dirty, locked, or pinned.
 */

static void __gfs2_ail_flush(struct gfs2_glock *gl, bool fsync,
			     unsigned int nr_revokes)
{
	struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
	struct list_head *head = &gl->gl_ail_list;
	struct gfs2_bufdata *bd, *tmp;
	struct buffer_head *bh;
	const unsigned long b_state = (1UL << BH_Dirty)|(1UL << BH_Pinned)|(1UL << BH_Lock);

	gfs2_log_lock(sdp);
	spin_lock(&sdp->sd_ail_lock);
	list_for_each_entry_safe_reverse(bd, tmp, head, bd_ail_gl_list) {
		if (nr_revokes == 0)
			break;
		bh = bd->bd_bh;
		if (bh->b_state & b_state) {
			if (fsync)
				continue;
			gfs2_ail_error(gl, bh);
		}
		gfs2_trans_add_revoke(sdp, bd);
		nr_revokes--;
	}
	GLOCK_BUG_ON(gl, !fsync && atomic_read(&gl->gl_ail_count));
	spin_unlock(&sdp->sd_ail_lock);
	gfs2_log_unlock(sdp);
}


static int gfs2_ail_empty_gl(struct gfs2_glock *gl)
{
	struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
	struct gfs2_trans tr;
	unsigned int revokes;
	int ret = 0;

	revokes = atomic_read(&gl->gl_ail_count);

	if (!revokes) {
		bool have_revokes;
		bool log_in_flight;

		/*
		 * We have nothing on the ail, but there could be revokes on
		 * the sdp revoke queue, in which case, we still want to flush
		 * the log and wait for it to finish.
		 *
		 * If the sdp revoke list is empty too, we might still have an
		 * io outstanding for writing revokes, so we should wait for
		 * it before returning.
		 *
		 * If none of these conditions are true, our revokes are all
		 * flushed and we can return.
		 */
		gfs2_log_lock(sdp);
		have_revokes = !list_empty(&sdp->sd_log_revokes);
		log_in_flight = atomic_read(&sdp->sd_log_in_flight);
		gfs2_log_unlock(sdp);
		if (have_revokes)
			goto flush;
		if (log_in_flight)
			log_flush_wait(sdp);
		return 0;
	}

	memset(&tr, 0, sizeof(tr));
	set_bit(TR_ONSTACK, &tr.tr_flags);
	ret = __gfs2_trans_begin(&tr, sdp, 0, revokes, _RET_IP_);
	if (ret) {
		fs_err(sdp, "Transaction error %d: Unable to write revokes.", ret);
		goto flush;
	}
	__gfs2_ail_flush(gl, 0, revokes);
	gfs2_trans_end(sdp);

flush:
	if (!ret)
		gfs2_log_flush(sdp, NULL, GFS2_LOG_HEAD_FLUSH_NORMAL |
				GFS2_LFC_AIL_EMPTY_GL);
	return ret;
}

void gfs2_ail_flush(struct gfs2_glock *gl, bool fsync)
{
	struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
	unsigned int revokes = atomic_read(&gl->gl_ail_count);
	int ret;

	if (!revokes)
		return;

	ret = gfs2_trans_begin(sdp, 0, revokes);
	if (ret)
		return;
	__gfs2_ail_flush(gl, fsync, revokes);
	gfs2_trans_end(sdp);
	gfs2_log_flush(sdp, NULL, GFS2_LOG_HEAD_FLUSH_NORMAL |
		       GFS2_LFC_AIL_FLUSH);
}

/**
 * gfs2_rgrp_metasync - sync out the metadata of a resource group
 * @gl: the glock protecting the resource group
 *
 */

static int gfs2_rgrp_metasync(struct gfs2_glock *gl)
{
	struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
	struct address_space *metamapping = &sdp->sd_aspace;
	struct gfs2_rgrpd *rgd = gfs2_glock2rgrp(gl);
	const unsigned bsize = sdp->sd_sb.sb_bsize;
	loff_t start = (rgd->rd_addr * bsize) & PAGE_MASK;
	loff_t end = PAGE_ALIGN((rgd->rd_addr + rgd->rd_length) * bsize) - 1;
	int error;

	filemap_fdatawrite_range(metamapping, start, end);
	error = filemap_fdatawait_range(metamapping, start, end);
	WARN_ON_ONCE(error && !gfs2_withdrawn(sdp));
	mapping_set_error(metamapping, error);
	if (error)
		gfs2_io_error(sdp);
	return error;
}

/**
 * rgrp_go_sync - sync out the metadata for this glock
 * @gl: the glock
 *
 * Called when demoting or unlocking an EX glock.  We must flush
 * to disk all dirty buffers/pages relating to this glock, and must not
 * return to caller to demote/unlock the glock until I/O is complete.
 */

static int rgrp_go_sync(struct gfs2_glock *gl)
{
	struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
	struct gfs2_rgrpd *rgd = gfs2_glock2rgrp(gl);
	int error;

	if (!rgd || !test_and_clear_bit(GLF_DIRTY, &gl->gl_flags))
		return 0;
	GLOCK_BUG_ON(gl, gl->gl_state != LM_ST_EXCLUSIVE);

	gfs2_log_flush(sdp, gl, GFS2_LOG_HEAD_FLUSH_NORMAL |
		       GFS2_LFC_RGRP_GO_SYNC);
	error = gfs2_rgrp_metasync(gl);
	if (!error)
		error = gfs2_ail_empty_gl(gl);
	gfs2_free_clones(rgd);
	return error;
}

/**
 * rgrp_go_inval - invalidate the metadata for this glock
 * @gl: the glock
 * @flags:
 *
 * We never used LM_ST_DEFERRED with resource groups, so that we
 * should always see the metadata flag set here.
 *
 */

static void rgrp_go_inval(struct gfs2_glock *gl, int flags)
{
	struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
	struct address_space *mapping = &sdp->sd_aspace;
	struct gfs2_rgrpd *rgd = gfs2_glock2rgrp(gl);
	const unsigned bsize = sdp->sd_sb.sb_bsize;
	loff_t start, end;

	if (!rgd)
		return;
	start = (rgd->rd_addr * bsize) & PAGE_MASK;
	end = PAGE_ALIGN((rgd->rd_addr + rgd->rd_length) * bsize) - 1;
	gfs2_rgrp_brelse(rgd);
	WARN_ON_ONCE(!(flags & DIO_METADATA));
	truncate_inode_pages_range(mapping, start, end);
}

static void gfs2_rgrp_go_dump(struct seq_file *seq, const struct gfs2_glock *gl,
			      const char *fs_id_buf)
{
	struct gfs2_rgrpd *rgd = gl->gl_object;

	if (rgd)
		gfs2_rgrp_dump(seq, rgd, fs_id_buf);
}

static struct gfs2_inode *gfs2_glock2inode(struct gfs2_glock *gl)
{
	struct gfs2_inode *ip;

	spin_lock(&gl->gl_lockref.lock);
	ip = gl->gl_object;
	if (ip)
		set_bit(GIF_GLOP_PENDING, &ip->i_flags);
	spin_unlock(&gl->gl_lockref.lock);
	return ip;
}

struct gfs2_rgrpd *gfs2_glock2rgrp(struct gfs2_glock *gl)
{
	struct gfs2_rgrpd *rgd;

	spin_lock(&gl->gl_lockref.lock);
	rgd = gl->gl_object;
	spin_unlock(&gl->gl_lockref.lock);

	return rgd;
}

static void gfs2_clear_glop_pending(struct gfs2_inode *ip)
{
	if (!ip)
		return;

	clear_bit_unlock(GIF_GLOP_PENDING, &ip->i_flags);
	wake_up_bit(&ip->i_flags, GIF_GLOP_PENDING);
}

/**
 * gfs2_inode_metasync - sync out the metadata of an inode
 * @gl: the glock protecting the inode
 *
 */
int gfs2_inode_metasync(struct gfs2_glock *gl)
{
	struct address_space *metamapping = gfs2_glock2aspace(gl);
	int error;

	filemap_fdatawrite(metamapping);
	error = filemap_fdatawait(metamapping);
	if (error)
		gfs2_io_error(gl->gl_name.ln_sbd);
	return error;
}

/**
 * inode_go_sync - Sync the dirty metadata of an inode
 * @gl: the glock protecting the inode
 *
 */

static int inode_go_sync(struct gfs2_glock *gl)
{
	struct gfs2_inode *ip = gfs2_glock2inode(gl);
	int isreg = ip && S_ISREG(ip->i_inode.i_mode);
	struct address_space *metamapping = gfs2_glock2aspace(gl);
	int error = 0, ret;

	if (isreg) {
		if (test_and_clear_bit(GIF_SW_PAGED, &ip->i_flags))
			unmap_shared_mapping_range(ip->i_inode.i_mapping, 0, 0);
		inode_dio_wait(&ip->i_inode);
	}
	if (!test_and_clear_bit(GLF_DIRTY, &gl->gl_flags))
		goto out;

	GLOCK_BUG_ON(gl, gl->gl_state != LM_ST_EXCLUSIVE);

	gfs2_log_flush(gl->gl_name.ln_sbd, gl, GFS2_LOG_HEAD_FLUSH_NORMAL |
		       GFS2_LFC_INODE_GO_SYNC);
	filemap_fdatawrite(metamapping);
	if (isreg) {
		struct address_space *mapping = ip->i_inode.i_mapping;
		filemap_fdatawrite(mapping);
		error = filemap_fdatawait(mapping);
		mapping_set_error(mapping, error);
	}
	ret = gfs2_inode_metasync(gl);
	if (!error)
		error = ret;
	ret = gfs2_ail_empty_gl(gl);
	if (!error)
		error = ret;
	/*
	 * Writeback of the data mapping may cause the dirty flag to be set
	 * so we have to clear it again here.
	 */
	smp_mb__before_atomic();
	clear_bit(GLF_DIRTY, &gl->gl_flags);

out:
	gfs2_clear_glop_pending(ip);
	return error;
}

/**
 * inode_go_inval - prepare a inode glock to be released
 * @gl: the glock
 * @flags:
 *
 * Normally we invalidate everything, but if we are moving into
 * LM_ST_DEFERRED from LM_ST_SHARED or LM_ST_EXCLUSIVE then we
 * can keep hold of the metadata, since it won't have changed.
 *
 */

static void inode_go_inval(struct gfs2_glock *gl, int flags)
{
	struct gfs2_inode *ip = gfs2_glock2inode(gl);

	if (flags & DIO_METADATA) {
		struct address_space *mapping = gfs2_glock2aspace(gl);
		truncate_inode_pages(mapping, 0);
		if (ip) {
			set_bit(GLF_INSTANTIATE_NEEDED, &gl->gl_flags);
			forget_all_cached_acls(&ip->i_inode);
			security_inode_invalidate_secctx(&ip->i_inode);
			gfs2_dir_hash_inval(ip);
		}
	}

	if (ip == GFS2_I(gl->gl_name.ln_sbd->sd_rindex)) {
		gfs2_log_flush(gl->gl_name.ln_sbd, NULL,
			       GFS2_LOG_HEAD_FLUSH_NORMAL |
			       GFS2_LFC_INODE_GO_INVAL);
		gl->gl_name.ln_sbd->sd_rindex_uptodate = 0;
	}
	if (ip && S_ISREG(ip->i_inode.i_mode))
		truncate_inode_pages(ip->i_inode.i_mapping, 0);

	gfs2_clear_glop_pending(ip);
}

/**
 * inode_go_demote_ok - Check to see if it's ok to unlock an inode glock
 * @gl: the glock
 *
 * Returns: 1 if it's ok
 */

static int inode_go_demote_ok(const struct gfs2_glock *gl)
{
	struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;

	if (sdp->sd_jindex == gl->gl_object || sdp->sd_rindex == gl->gl_object)
		return 0;

	return 1;
}

static int gfs2_dinode_in(struct gfs2_inode *ip, const void *buf)
{
	struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
	const struct gfs2_dinode *str = buf;
	struct timespec64 atime;
	u16 height, depth;
	umode_t mode = be32_to_cpu(str->di_mode);
	struct inode *inode = &ip->i_inode;
	bool is_new = inode->i_state & I_NEW;

	if (unlikely(ip->i_no_addr != be64_to_cpu(str->di_num.no_addr)))
		goto corrupt;
	if (unlikely(!is_new && inode_wrong_type(inode, mode)))
		goto corrupt;
	ip->i_no_formal_ino = be64_to_cpu(str->di_num.no_formal_ino);
	inode->i_mode = mode;
	if (is_new) {
		inode->i_rdev = 0;
		switch (mode & S_IFMT) {
		case S_IFBLK:
		case S_IFCHR:
			inode->i_rdev = MKDEV(be32_to_cpu(str->di_major),
					      be32_to_cpu(str->di_minor));
			break;
		}
	}

	i_uid_write(inode, be32_to_cpu(str->di_uid));
	i_gid_write(inode, be32_to_cpu(str->di_gid));
	set_nlink(inode, be32_to_cpu(str->di_nlink));
	i_size_write(inode, be64_to_cpu(str->di_size));
	gfs2_set_inode_blocks(inode, be64_to_cpu(str->di_blocks));
	atime.tv_sec = be64_to_cpu(str->di_atime);
	atime.tv_nsec = be32_to_cpu(str->di_atime_nsec);
	if (timespec64_compare(&inode->i_atime, &atime) < 0)
		inode->i_atime = atime;
	inode->i_mtime.tv_sec = be64_to_cpu(str->di_mtime);
	inode->i_mtime.tv_nsec = be32_to_cpu(str->di_mtime_nsec);
	inode_set_ctime(inode, be64_to_cpu(str->di_ctime),
			be32_to_cpu(str->di_ctime_nsec));

	ip->i_goal = be64_to_cpu(str->di_goal_meta);
	ip->i_generation = be64_to_cpu(str->di_generation);

	ip->i_diskflags = be32_to_cpu(str->di_flags);
	ip->i_eattr = be64_to_cpu(str->di_eattr);
	/* i_diskflags and i_eattr must be set before gfs2_set_inode_flags() */
	gfs2_set_inode_flags(inode);
	height = be16_to_cpu(str->di_height);
	if (unlikely(height > sdp->sd_max_height))
		goto corrupt;
	ip->i_height = (u8)height;

	depth = be16_to_cpu(str->di_depth);
	if (unlikely(depth > GFS2_DIR_MAX_DEPTH))
		goto corrupt;
	ip->i_depth = (u8)depth;
	ip->i_entries = be32_to_cpu(str->di_entries);

	if (gfs2_is_stuffed(ip) && inode->i_size > gfs2_max_stuffed_size(ip))
		goto corrupt;

	if (S_ISREG(inode->i_mode))
		gfs2_set_aops(inode);

	return 0;
corrupt:
	gfs2_consist_inode(ip);
	return -EIO;
}

/**
 * gfs2_inode_refresh - Refresh the incore copy of the dinode
 * @ip: The GFS2 inode
 *
 * Returns: errno
 */

int gfs2_inode_refresh(struct gfs2_inode *ip)
{
	struct buffer_head *dibh;
	int error;

	error = gfs2_meta_inode_buffer(ip, &dibh);
	if (error)
		return error;

	error = gfs2_dinode_in(ip, dibh->b_data);
	brelse(dibh);
	return error;
}

/**
 * inode_go_instantiate - read in an inode if necessary
 * @gh: The glock holder
 *
 * Returns: errno
 */

static int inode_go_instantiate(struct gfs2_glock *gl)
{
	struct gfs2_inode *ip = gl->gl_object;

	if (!ip) /* no inode to populate - read it in later */
		return 0;

	return gfs2_inode_refresh(ip);
}

static int inode_go_held(struct gfs2_holder *gh)
{
	struct gfs2_glock *gl = gh->gh_gl;
	struct gfs2_inode *ip = gl->gl_object;
	int error = 0;

	if (!ip) /* no inode to populate - read it in later */
		return 0;

	if (gh->gh_state != LM_ST_DEFERRED)
		inode_dio_wait(&ip->i_inode);

	if ((ip->i_diskflags & GFS2_DIF_TRUNC_IN_PROG) &&
	    (gl->gl_state == LM_ST_EXCLUSIVE) &&
	    (gh->gh_state == LM_ST_EXCLUSIVE))
		error = gfs2_truncatei_resume(ip);

	return error;
}

/**
 * inode_go_dump - print information about an inode
 * @seq: The iterator
 * @gl: The glock
 * @fs_id_buf: file system id (may be empty)
 *
 */

static void inode_go_dump(struct seq_file *seq, const struct gfs2_glock *gl,
			  const char *fs_id_buf)
{
	struct gfs2_inode *ip = gl->gl_object;
	const struct inode *inode = &ip->i_inode;

	if (ip == NULL)
		return;

	gfs2_print_dbg(seq, "%s I: n:%llu/%llu t:%u f:0x%02lx d:0x%08x s:%llu "
		       "p:%lu\n", fs_id_buf,
		  (unsigned long long)ip->i_no_formal_ino,
		  (unsigned long long)ip->i_no_addr,
		  IF2DT(inode->i_mode), ip->i_flags,
		  (unsigned int)ip->i_diskflags,
		  (unsigned long long)i_size_read(inode),
		  inode->i_data.nrpages);
}

/**
 * freeze_go_callback - A cluster node is requesting a freeze
 * @gl: the glock
 * @remote: true if this came from a different cluster node
 */

static void freeze_go_callback(struct gfs2_glock *gl, bool remote)
{
	struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
	struct super_block *sb = sdp->sd_vfs;

	if (!remote ||
	    gl->gl_state != LM_ST_SHARED ||
	    gl->gl_demote_state != LM_ST_UNLOCKED)
		return;

	/*
	 * Try to get an active super block reference to prevent racing with
	 * unmount (see trylock_super()).  But note that unmount isn't the only
	 * place where a write lock on s_umount is taken, and we can fail here
	 * because of things like remount as well.
	 */
	if (down_read_trylock(&sb->s_umount)) {
		atomic_inc(&sb->s_active);
		up_read(&sb->s_umount);
		if (!queue_work(gfs2_freeze_wq, &sdp->sd_freeze_work))
			deactivate_super(sb);
	}
}

/**
 * freeze_go_xmote_bh - After promoting/demoting the freeze glock
 * @gl: the glock
 */
static int freeze_go_xmote_bh(struct gfs2_glock *gl)
{
	struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
	struct gfs2_inode *ip = GFS2_I(sdp->sd_jdesc->jd_inode);
	struct gfs2_glock *j_gl = ip->i_gl;
	struct gfs2_log_header_host head;
	int error;

	if (test_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags)) {
		j_gl->gl_ops->go_inval(j_gl, DIO_METADATA);

		error = gfs2_find_jhead(sdp->sd_jdesc, &head, false);
		if (gfs2_assert_withdraw_delayed(sdp, !error))
			return error;
		if (gfs2_assert_withdraw_delayed(sdp, head.lh_flags &
						 GFS2_LOG_HEAD_UNMOUNT))
			return -EIO;
		sdp->sd_log_sequence = head.lh_sequence + 1;
		gfs2_log_pointers_init(sdp, head.lh_blkno);
	}
	return 0;
}

/**
 * freeze_go_demote_ok
 * @gl: the glock
 *
 * Always returns 0
 */

static int freeze_go_demote_ok(const struct gfs2_glock *gl)
{
	return 0;
}

/**
 * iopen_go_callback - schedule the dcache entry for the inode to be deleted
 * @gl: the glock
 * @remote: true if this came from a different cluster node
 *
 * gl_lockref.lock lock is held while calling this
 */
static void iopen_go_callback(struct gfs2_glock *gl, bool remote)
{
	struct gfs2_inode *ip = gl->gl_object;
	struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;

	if (!remote || sb_rdonly(sdp->sd_vfs) ||
	    test_bit(SDF_KILL, &sdp->sd_flags))
		return;

	if (gl->gl_demote_state == LM_ST_UNLOCKED &&
	    gl->gl_state == LM_ST_SHARED && ip) {
		gl->gl_lockref.count++;
		if (!gfs2_queue_try_to_evict(gl))
			gl->gl_lockref.count--;
	}
}

/**
 * inode_go_free - wake up anyone waiting for dlm's unlock ast to free it
 * @gl: glock being freed
 *
 * For now, this is only used for the journal inode glock. In withdraw
 * situations, we need to wait for the glock to be freed so that we know
 * other nodes may proceed with recovery / journal replay.
 */
static void inode_go_free(struct gfs2_glock *gl)
{
	/* Note that we cannot reference gl_object because it's already set
	 * to NULL by this point in its lifecycle. */
	if (!test_bit(GLF_FREEING, &gl->gl_flags))
		return;
	clear_bit_unlock(GLF_FREEING, &gl->gl_flags);
	wake_up_bit(&gl->gl_flags, GLF_FREEING);
}

/**
 * nondisk_go_callback - used to signal when a node did a withdraw
 * @gl: the nondisk glock
 * @remote: true if this came from a different cluster node
 *
 */
static void nondisk_go_callback(struct gfs2_glock *gl, bool remote)
{
	struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;

	/* Ignore the callback unless it's from another node, and it's the
	   live lock. */
	if (!remote || gl->gl_name.ln_number != GFS2_LIVE_LOCK)
		return;

	/* First order of business is to cancel the demote request. We don't
	 * really want to demote a nondisk glock. At best it's just to inform
	 * us of another node's withdraw. We'll keep it in SH mode. */
	clear_bit(GLF_DEMOTE, &gl->gl_flags);
	clear_bit(GLF_PENDING_DEMOTE, &gl->gl_flags);

	/* Ignore the unlock if we're withdrawn, unmounting, or in recovery. */
	if (test_bit(SDF_NORECOVERY, &sdp->sd_flags) ||
	    test_bit(SDF_WITHDRAWN, &sdp->sd_flags) ||
	    test_bit(SDF_REMOTE_WITHDRAW, &sdp->sd_flags))
		return;

	/* We only care when a node wants us to unlock, because that means
	 * they want a journal recovered. */
	if (gl->gl_demote_state != LM_ST_UNLOCKED)
		return;

	if (sdp->sd_args.ar_spectator) {
		fs_warn(sdp, "Spectator node cannot recover journals.\n");
		return;
	}

	fs_warn(sdp, "Some node has withdrawn; checking for recovery.\n");
	set_bit(SDF_REMOTE_WITHDRAW, &sdp->sd_flags);
	/*
	 * We can't call remote_withdraw directly here or gfs2_recover_journal
	 * because this is called from the glock unlock function and the
	 * remote_withdraw needs to enqueue and dequeue the same "live" glock
	 * we were called from. So we queue it to the control work queue in
	 * lock_dlm.
	 */
	queue_delayed_work(gfs2_control_wq, &sdp->sd_control_work, 0);
}

const struct gfs2_glock_operations gfs2_meta_glops = {
	.go_type = LM_TYPE_META,
	.go_flags = GLOF_NONDISK,
};

const struct gfs2_glock_operations gfs2_inode_glops = {
	.go_sync = inode_go_sync,
	.go_inval = inode_go_inval,
	.go_demote_ok = inode_go_demote_ok,
	.go_instantiate = inode_go_instantiate,
	.go_held = inode_go_held,
	.go_dump = inode_go_dump,
	.go_type = LM_TYPE_INODE,
	.go_flags = GLOF_ASPACE | GLOF_LRU | GLOF_LVB,
	.go_free = inode_go_free,
};

const struct gfs2_glock_operations gfs2_rgrp_glops = {
	.go_sync = rgrp_go_sync,
	.go_inval = rgrp_go_inval,
	.go_instantiate = gfs2_rgrp_go_instantiate,
	.go_dump = gfs2_rgrp_go_dump,
	.go_type = LM_TYPE_RGRP,
	.go_flags = GLOF_LVB,
};

const struct gfs2_glock_operations gfs2_freeze_glops = {
	.go_xmote_bh = freeze_go_xmote_bh,
	.go_demote_ok = freeze_go_demote_ok,
	.go_callback = freeze_go_callback,
	.go_type = LM_TYPE_NONDISK,
	.go_flags = GLOF_NONDISK,
};

const struct gfs2_glock_operations gfs2_iopen_glops = {
	.go_type = LM_TYPE_IOPEN,
	.go_callback = iopen_go_callback,
	.go_dump = inode_go_dump,
	.go_flags = GLOF_LRU | GLOF_NONDISK,
	.go_subclass = 1,
};

const struct gfs2_glock_operations gfs2_flock_glops = {
	.go_type = LM_TYPE_FLOCK,
	.go_flags = GLOF_LRU | GLOF_NONDISK,
};

const struct gfs2_glock_operations gfs2_nondisk_glops = {
	.go_type = LM_TYPE_NONDISK,
	.go_flags = GLOF_NONDISK,
	.go_callback = nondisk_go_callback,
};

const struct gfs2_glock_operations gfs2_quota_glops = {
	.go_type = LM_TYPE_QUOTA,
	.go_flags = GLOF_LVB | GLOF_LRU | GLOF_NONDISK,
};

const struct gfs2_glock_operations gfs2_journal_glops = {
	.go_type = LM_TYPE_JOURNAL,
	.go_flags = GLOF_NONDISK,
};

const struct gfs2_glock_operations *gfs2_glops_list[] = {
	[LM_TYPE_META] = &gfs2_meta_glops,
	[LM_TYPE_INODE] = &gfs2_inode_glops,
	[LM_TYPE_RGRP] = &gfs2_rgrp_glops,
	[LM_TYPE_IOPEN] = &gfs2_iopen_glops,
	[LM_TYPE_FLOCK] = &gfs2_flock_glops,
	[LM_TYPE_NONDISK] = &gfs2_nondisk_glops,
	[LM_TYPE_QUOTA] = &gfs2_quota_glops,
	[LM_TYPE_JOURNAL] = &gfs2_journal_glops,
};