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1/*
2 * Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
3 * Copyright (C) 2004-2007 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/sched.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/delay.h>
18#include <linux/kthread.h>
19#include <linux/freezer.h>
20#include <linux/bio.h>
21#include <linux/blkdev.h>
22#include <linux/writeback.h>
23#include <linux/list_sort.h>
24
25#include "gfs2.h"
26#include "incore.h"
27#include "bmap.h"
28#include "glock.h"
29#include "log.h"
30#include "lops.h"
31#include "meta_io.h"
32#include "util.h"
33#include "dir.h"
34#include "trace_gfs2.h"
35
36/**
37 * gfs2_struct2blk - compute stuff
38 * @sdp: the filesystem
39 * @nstruct: the number of structures
40 * @ssize: the size of the structures
41 *
42 * Compute the number of log descriptor blocks needed to hold a certain number
43 * of structures of a certain size.
44 *
45 * Returns: the number of blocks needed (minimum is always 1)
46 */
47
48unsigned int gfs2_struct2blk(struct gfs2_sbd *sdp, unsigned int nstruct,
49 unsigned int ssize)
50{
51 unsigned int blks;
52 unsigned int first, second;
53
54 blks = 1;
55 first = (sdp->sd_sb.sb_bsize - sizeof(struct gfs2_log_descriptor)) / ssize;
56
57 if (nstruct > first) {
58 second = (sdp->sd_sb.sb_bsize -
59 sizeof(struct gfs2_meta_header)) / ssize;
60 blks += DIV_ROUND_UP(nstruct - first, second);
61 }
62
63 return blks;
64}
65
66/**
67 * gfs2_remove_from_ail - Remove an entry from the ail lists, updating counters
68 * @mapping: The associated mapping (maybe NULL)
69 * @bd: The gfs2_bufdata to remove
70 *
71 * The ail lock _must_ be held when calling this function
72 *
73 */
74
75void gfs2_remove_from_ail(struct gfs2_bufdata *bd)
76{
77 bd->bd_tr = NULL;
78 list_del_init(&bd->bd_ail_st_list);
79 list_del_init(&bd->bd_ail_gl_list);
80 atomic_dec(&bd->bd_gl->gl_ail_count);
81 brelse(bd->bd_bh);
82}
83
84/**
85 * gfs2_ail1_start_one - Start I/O on a part of the AIL
86 * @sdp: the filesystem
87 * @wbc: The writeback control structure
88 * @ai: The ail structure
89 *
90 */
91
92static int gfs2_ail1_start_one(struct gfs2_sbd *sdp,
93 struct writeback_control *wbc,
94 struct gfs2_trans *tr)
95__releases(&sdp->sd_ail_lock)
96__acquires(&sdp->sd_ail_lock)
97{
98 struct gfs2_glock *gl = NULL;
99 struct address_space *mapping;
100 struct gfs2_bufdata *bd, *s;
101 struct buffer_head *bh;
102
103 list_for_each_entry_safe_reverse(bd, s, &tr->tr_ail1_list, bd_ail_st_list) {
104 bh = bd->bd_bh;
105
106 gfs2_assert(sdp, bd->bd_tr == tr);
107
108 if (!buffer_busy(bh)) {
109 if (!buffer_uptodate(bh))
110 gfs2_io_error_bh(sdp, bh);
111 list_move(&bd->bd_ail_st_list, &tr->tr_ail2_list);
112 continue;
113 }
114
115 if (!buffer_dirty(bh))
116 continue;
117 if (gl == bd->bd_gl)
118 continue;
119 gl = bd->bd_gl;
120 list_move(&bd->bd_ail_st_list, &tr->tr_ail1_list);
121 mapping = bh->b_page->mapping;
122 if (!mapping)
123 continue;
124 spin_unlock(&sdp->sd_ail_lock);
125 generic_writepages(mapping, wbc);
126 spin_lock(&sdp->sd_ail_lock);
127 if (wbc->nr_to_write <= 0)
128 break;
129 return 1;
130 }
131
132 return 0;
133}
134
135
136/**
137 * gfs2_ail1_flush - start writeback of some ail1 entries
138 * @sdp: The super block
139 * @wbc: The writeback control structure
140 *
141 * Writes back some ail1 entries, according to the limits in the
142 * writeback control structure
143 */
144
145void gfs2_ail1_flush(struct gfs2_sbd *sdp, struct writeback_control *wbc)
146{
147 struct list_head *head = &sdp->sd_ail1_list;
148 struct gfs2_trans *tr;
149 struct blk_plug plug;
150
151 trace_gfs2_ail_flush(sdp, wbc, 1);
152 blk_start_plug(&plug);
153 spin_lock(&sdp->sd_ail_lock);
154restart:
155 list_for_each_entry_reverse(tr, head, tr_list) {
156 if (wbc->nr_to_write <= 0)
157 break;
158 if (gfs2_ail1_start_one(sdp, wbc, tr))
159 goto restart;
160 }
161 spin_unlock(&sdp->sd_ail_lock);
162 blk_finish_plug(&plug);
163 trace_gfs2_ail_flush(sdp, wbc, 0);
164}
165
166/**
167 * gfs2_ail1_start - start writeback of all ail1 entries
168 * @sdp: The superblock
169 */
170
171static void gfs2_ail1_start(struct gfs2_sbd *sdp)
172{
173 struct writeback_control wbc = {
174 .sync_mode = WB_SYNC_NONE,
175 .nr_to_write = LONG_MAX,
176 .range_start = 0,
177 .range_end = LLONG_MAX,
178 };
179
180 return gfs2_ail1_flush(sdp, &wbc);
181}
182
183/**
184 * gfs2_ail1_empty_one - Check whether or not a trans in the AIL has been synced
185 * @sdp: the filesystem
186 * @ai: the AIL entry
187 *
188 */
189
190static void gfs2_ail1_empty_one(struct gfs2_sbd *sdp, struct gfs2_trans *tr)
191{
192 struct gfs2_bufdata *bd, *s;
193 struct buffer_head *bh;
194
195 list_for_each_entry_safe_reverse(bd, s, &tr->tr_ail1_list,
196 bd_ail_st_list) {
197 bh = bd->bd_bh;
198 gfs2_assert(sdp, bd->bd_tr == tr);
199 if (buffer_busy(bh))
200 continue;
201 if (!buffer_uptodate(bh))
202 gfs2_io_error_bh(sdp, bh);
203 list_move(&bd->bd_ail_st_list, &tr->tr_ail2_list);
204 }
205
206}
207
208/**
209 * gfs2_ail1_empty - Try to empty the ail1 lists
210 * @sdp: The superblock
211 *
212 * Tries to empty the ail1 lists, starting with the oldest first
213 */
214
215static int gfs2_ail1_empty(struct gfs2_sbd *sdp)
216{
217 struct gfs2_trans *tr, *s;
218 int oldest_tr = 1;
219 int ret;
220
221 spin_lock(&sdp->sd_ail_lock);
222 list_for_each_entry_safe_reverse(tr, s, &sdp->sd_ail1_list, tr_list) {
223 gfs2_ail1_empty_one(sdp, tr);
224 if (list_empty(&tr->tr_ail1_list) && oldest_tr)
225 list_move(&tr->tr_list, &sdp->sd_ail2_list);
226 else
227 oldest_tr = 0;
228 }
229 ret = list_empty(&sdp->sd_ail1_list);
230 spin_unlock(&sdp->sd_ail_lock);
231
232 return ret;
233}
234
235static void gfs2_ail1_wait(struct gfs2_sbd *sdp)
236{
237 struct gfs2_trans *tr;
238 struct gfs2_bufdata *bd;
239 struct buffer_head *bh;
240
241 spin_lock(&sdp->sd_ail_lock);
242 list_for_each_entry_reverse(tr, &sdp->sd_ail1_list, tr_list) {
243 list_for_each_entry(bd, &tr->tr_ail1_list, bd_ail_st_list) {
244 bh = bd->bd_bh;
245 if (!buffer_locked(bh))
246 continue;
247 get_bh(bh);
248 spin_unlock(&sdp->sd_ail_lock);
249 wait_on_buffer(bh);
250 brelse(bh);
251 return;
252 }
253 }
254 spin_unlock(&sdp->sd_ail_lock);
255}
256
257/**
258 * gfs2_ail2_empty_one - Check whether or not a trans in the AIL has been synced
259 * @sdp: the filesystem
260 * @ai: the AIL entry
261 *
262 */
263
264static void gfs2_ail2_empty_one(struct gfs2_sbd *sdp, struct gfs2_trans *tr)
265{
266 struct list_head *head = &tr->tr_ail2_list;
267 struct gfs2_bufdata *bd;
268
269 while (!list_empty(head)) {
270 bd = list_entry(head->prev, struct gfs2_bufdata,
271 bd_ail_st_list);
272 gfs2_assert(sdp, bd->bd_tr == tr);
273 gfs2_remove_from_ail(bd);
274 }
275}
276
277static void ail2_empty(struct gfs2_sbd *sdp, unsigned int new_tail)
278{
279 struct gfs2_trans *tr, *safe;
280 unsigned int old_tail = sdp->sd_log_tail;
281 int wrap = (new_tail < old_tail);
282 int a, b, rm;
283
284 spin_lock(&sdp->sd_ail_lock);
285
286 list_for_each_entry_safe(tr, safe, &sdp->sd_ail2_list, tr_list) {
287 a = (old_tail <= tr->tr_first);
288 b = (tr->tr_first < new_tail);
289 rm = (wrap) ? (a || b) : (a && b);
290 if (!rm)
291 continue;
292
293 gfs2_ail2_empty_one(sdp, tr);
294 list_del(&tr->tr_list);
295 gfs2_assert_warn(sdp, list_empty(&tr->tr_ail1_list));
296 gfs2_assert_warn(sdp, list_empty(&tr->tr_ail2_list));
297 kfree(tr);
298 }
299
300 spin_unlock(&sdp->sd_ail_lock);
301}
302
303/**
304 * gfs2_log_release - Release a given number of log blocks
305 * @sdp: The GFS2 superblock
306 * @blks: The number of blocks
307 *
308 */
309
310void gfs2_log_release(struct gfs2_sbd *sdp, unsigned int blks)
311{
312
313 atomic_add(blks, &sdp->sd_log_blks_free);
314 trace_gfs2_log_blocks(sdp, blks);
315 gfs2_assert_withdraw(sdp, atomic_read(&sdp->sd_log_blks_free) <=
316 sdp->sd_jdesc->jd_blocks);
317 up_read(&sdp->sd_log_flush_lock);
318}
319
320/**
321 * gfs2_log_reserve - Make a log reservation
322 * @sdp: The GFS2 superblock
323 * @blks: The number of blocks to reserve
324 *
325 * Note that we never give out the last few blocks of the journal. Thats
326 * due to the fact that there is a small number of header blocks
327 * associated with each log flush. The exact number can't be known until
328 * flush time, so we ensure that we have just enough free blocks at all
329 * times to avoid running out during a log flush.
330 *
331 * We no longer flush the log here, instead we wake up logd to do that
332 * for us. To avoid the thundering herd and to ensure that we deal fairly
333 * with queued waiters, we use an exclusive wait. This means that when we
334 * get woken with enough journal space to get our reservation, we need to
335 * wake the next waiter on the list.
336 *
337 * Returns: errno
338 */
339
340int gfs2_log_reserve(struct gfs2_sbd *sdp, unsigned int blks)
341{
342 int ret = 0;
343 unsigned reserved_blks = 7 * (4096 / sdp->sd_vfs->s_blocksize);
344 unsigned wanted = blks + reserved_blks;
345 DEFINE_WAIT(wait);
346 int did_wait = 0;
347 unsigned int free_blocks;
348
349 if (gfs2_assert_warn(sdp, blks) ||
350 gfs2_assert_warn(sdp, blks <= sdp->sd_jdesc->jd_blocks))
351 return -EINVAL;
352retry:
353 free_blocks = atomic_read(&sdp->sd_log_blks_free);
354 if (unlikely(free_blocks <= wanted)) {
355 do {
356 prepare_to_wait_exclusive(&sdp->sd_log_waitq, &wait,
357 TASK_UNINTERRUPTIBLE);
358 wake_up(&sdp->sd_logd_waitq);
359 did_wait = 1;
360 if (atomic_read(&sdp->sd_log_blks_free) <= wanted)
361 io_schedule();
362 free_blocks = atomic_read(&sdp->sd_log_blks_free);
363 } while(free_blocks <= wanted);
364 finish_wait(&sdp->sd_log_waitq, &wait);
365 }
366 atomic_inc(&sdp->sd_reserving_log);
367 if (atomic_cmpxchg(&sdp->sd_log_blks_free, free_blocks,
368 free_blocks - blks) != free_blocks) {
369 if (atomic_dec_and_test(&sdp->sd_reserving_log))
370 wake_up(&sdp->sd_reserving_log_wait);
371 goto retry;
372 }
373 trace_gfs2_log_blocks(sdp, -blks);
374
375 /*
376 * If we waited, then so might others, wake them up _after_ we get
377 * our share of the log.
378 */
379 if (unlikely(did_wait))
380 wake_up(&sdp->sd_log_waitq);
381
382 down_read(&sdp->sd_log_flush_lock);
383 if (unlikely(!test_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags))) {
384 gfs2_log_release(sdp, blks);
385 ret = -EROFS;
386 }
387 if (atomic_dec_and_test(&sdp->sd_reserving_log))
388 wake_up(&sdp->sd_reserving_log_wait);
389 return ret;
390}
391
392/**
393 * log_distance - Compute distance between two journal blocks
394 * @sdp: The GFS2 superblock
395 * @newer: The most recent journal block of the pair
396 * @older: The older journal block of the pair
397 *
398 * Compute the distance (in the journal direction) between two
399 * blocks in the journal
400 *
401 * Returns: the distance in blocks
402 */
403
404static inline unsigned int log_distance(struct gfs2_sbd *sdp, unsigned int newer,
405 unsigned int older)
406{
407 int dist;
408
409 dist = newer - older;
410 if (dist < 0)
411 dist += sdp->sd_jdesc->jd_blocks;
412
413 return dist;
414}
415
416/**
417 * calc_reserved - Calculate the number of blocks to reserve when
418 * refunding a transaction's unused buffers.
419 * @sdp: The GFS2 superblock
420 *
421 * This is complex. We need to reserve room for all our currently used
422 * metadata buffers (e.g. normal file I/O rewriting file time stamps) and
423 * all our journaled data buffers for journaled files (e.g. files in the
424 * meta_fs like rindex, or files for which chattr +j was done.)
425 * If we don't reserve enough space, gfs2_log_refund and gfs2_log_flush
426 * will count it as free space (sd_log_blks_free) and corruption will follow.
427 *
428 * We can have metadata bufs and jdata bufs in the same journal. So each
429 * type gets its own log header, for which we need to reserve a block.
430 * In fact, each type has the potential for needing more than one header
431 * in cases where we have more buffers than will fit on a journal page.
432 * Metadata journal entries take up half the space of journaled buffer entries.
433 * Thus, metadata entries have buf_limit (502) and journaled buffers have
434 * databuf_limit (251) before they cause a wrap around.
435 *
436 * Also, we need to reserve blocks for revoke journal entries and one for an
437 * overall header for the lot.
438 *
439 * Returns: the number of blocks reserved
440 */
441static unsigned int calc_reserved(struct gfs2_sbd *sdp)
442{
443 unsigned int reserved = 0;
444 unsigned int mbuf;
445 unsigned int dbuf;
446 struct gfs2_trans *tr = sdp->sd_log_tr;
447
448 if (tr) {
449 mbuf = tr->tr_num_buf_new - tr->tr_num_buf_rm;
450 dbuf = tr->tr_num_databuf_new - tr->tr_num_databuf_rm;
451 reserved = mbuf + dbuf;
452 /* Account for header blocks */
453 reserved += DIV_ROUND_UP(mbuf, buf_limit(sdp));
454 reserved += DIV_ROUND_UP(dbuf, databuf_limit(sdp));
455 }
456
457 if (sdp->sd_log_commited_revoke > 0)
458 reserved += gfs2_struct2blk(sdp, sdp->sd_log_commited_revoke,
459 sizeof(u64));
460 /* One for the overall header */
461 if (reserved)
462 reserved++;
463 return reserved;
464}
465
466static unsigned int current_tail(struct gfs2_sbd *sdp)
467{
468 struct gfs2_trans *tr;
469 unsigned int tail;
470
471 spin_lock(&sdp->sd_ail_lock);
472
473 if (list_empty(&sdp->sd_ail1_list)) {
474 tail = sdp->sd_log_head;
475 } else {
476 tr = list_entry(sdp->sd_ail1_list.prev, struct gfs2_trans,
477 tr_list);
478 tail = tr->tr_first;
479 }
480
481 spin_unlock(&sdp->sd_ail_lock);
482
483 return tail;
484}
485
486static void log_pull_tail(struct gfs2_sbd *sdp, unsigned int new_tail)
487{
488 unsigned int dist = log_distance(sdp, new_tail, sdp->sd_log_tail);
489
490 ail2_empty(sdp, new_tail);
491
492 atomic_add(dist, &sdp->sd_log_blks_free);
493 trace_gfs2_log_blocks(sdp, dist);
494 gfs2_assert_withdraw(sdp, atomic_read(&sdp->sd_log_blks_free) <=
495 sdp->sd_jdesc->jd_blocks);
496
497 sdp->sd_log_tail = new_tail;
498}
499
500
501static void log_flush_wait(struct gfs2_sbd *sdp)
502{
503 DEFINE_WAIT(wait);
504
505 if (atomic_read(&sdp->sd_log_in_flight)) {
506 do {
507 prepare_to_wait(&sdp->sd_log_flush_wait, &wait,
508 TASK_UNINTERRUPTIBLE);
509 if (atomic_read(&sdp->sd_log_in_flight))
510 io_schedule();
511 } while(atomic_read(&sdp->sd_log_in_flight));
512 finish_wait(&sdp->sd_log_flush_wait, &wait);
513 }
514}
515
516static int ip_cmp(void *priv, struct list_head *a, struct list_head *b)
517{
518 struct gfs2_inode *ipa, *ipb;
519
520 ipa = list_entry(a, struct gfs2_inode, i_ordered);
521 ipb = list_entry(b, struct gfs2_inode, i_ordered);
522
523 if (ipa->i_no_addr < ipb->i_no_addr)
524 return -1;
525 if (ipa->i_no_addr > ipb->i_no_addr)
526 return 1;
527 return 0;
528}
529
530static void gfs2_ordered_write(struct gfs2_sbd *sdp)
531{
532 struct gfs2_inode *ip;
533 LIST_HEAD(written);
534
535 spin_lock(&sdp->sd_ordered_lock);
536 list_sort(NULL, &sdp->sd_log_le_ordered, &ip_cmp);
537 while (!list_empty(&sdp->sd_log_le_ordered)) {
538 ip = list_entry(sdp->sd_log_le_ordered.next, struct gfs2_inode, i_ordered);
539 list_move(&ip->i_ordered, &written);
540 if (ip->i_inode.i_mapping->nrpages == 0)
541 continue;
542 spin_unlock(&sdp->sd_ordered_lock);
543 filemap_fdatawrite(ip->i_inode.i_mapping);
544 spin_lock(&sdp->sd_ordered_lock);
545 }
546 list_splice(&written, &sdp->sd_log_le_ordered);
547 spin_unlock(&sdp->sd_ordered_lock);
548}
549
550static void gfs2_ordered_wait(struct gfs2_sbd *sdp)
551{
552 struct gfs2_inode *ip;
553
554 spin_lock(&sdp->sd_ordered_lock);
555 while (!list_empty(&sdp->sd_log_le_ordered)) {
556 ip = list_entry(sdp->sd_log_le_ordered.next, struct gfs2_inode, i_ordered);
557 list_del(&ip->i_ordered);
558 WARN_ON(!test_and_clear_bit(GIF_ORDERED, &ip->i_flags));
559 if (ip->i_inode.i_mapping->nrpages == 0)
560 continue;
561 spin_unlock(&sdp->sd_ordered_lock);
562 filemap_fdatawait(ip->i_inode.i_mapping);
563 spin_lock(&sdp->sd_ordered_lock);
564 }
565 spin_unlock(&sdp->sd_ordered_lock);
566}
567
568void gfs2_ordered_del_inode(struct gfs2_inode *ip)
569{
570 struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
571
572 spin_lock(&sdp->sd_ordered_lock);
573 if (test_and_clear_bit(GIF_ORDERED, &ip->i_flags))
574 list_del(&ip->i_ordered);
575 spin_unlock(&sdp->sd_ordered_lock);
576}
577
578void gfs2_add_revoke(struct gfs2_sbd *sdp, struct gfs2_bufdata *bd)
579{
580 struct buffer_head *bh = bd->bd_bh;
581 struct gfs2_glock *gl = bd->bd_gl;
582
583 bh->b_private = NULL;
584 bd->bd_blkno = bh->b_blocknr;
585 gfs2_remove_from_ail(bd); /* drops ref on bh */
586 bd->bd_bh = NULL;
587 bd->bd_ops = &gfs2_revoke_lops;
588 sdp->sd_log_num_revoke++;
589 atomic_inc(&gl->gl_revokes);
590 set_bit(GLF_LFLUSH, &gl->gl_flags);
591 list_add(&bd->bd_list, &sdp->sd_log_le_revoke);
592}
593
594void gfs2_write_revokes(struct gfs2_sbd *sdp)
595{
596 struct gfs2_trans *tr;
597 struct gfs2_bufdata *bd, *tmp;
598 int have_revokes = 0;
599 int max_revokes = (sdp->sd_sb.sb_bsize - sizeof(struct gfs2_log_descriptor)) / sizeof(u64);
600
601 gfs2_ail1_empty(sdp);
602 spin_lock(&sdp->sd_ail_lock);
603 list_for_each_entry(tr, &sdp->sd_ail1_list, tr_list) {
604 list_for_each_entry(bd, &tr->tr_ail2_list, bd_ail_st_list) {
605 if (list_empty(&bd->bd_list)) {
606 have_revokes = 1;
607 goto done;
608 }
609 }
610 }
611done:
612 spin_unlock(&sdp->sd_ail_lock);
613 if (have_revokes == 0)
614 return;
615 while (sdp->sd_log_num_revoke > max_revokes)
616 max_revokes += (sdp->sd_sb.sb_bsize - sizeof(struct gfs2_meta_header)) / sizeof(u64);
617 max_revokes -= sdp->sd_log_num_revoke;
618 if (!sdp->sd_log_num_revoke) {
619 atomic_dec(&sdp->sd_log_blks_free);
620 /* If no blocks have been reserved, we need to also
621 * reserve a block for the header */
622 if (!sdp->sd_log_blks_reserved)
623 atomic_dec(&sdp->sd_log_blks_free);
624 }
625 gfs2_log_lock(sdp);
626 spin_lock(&sdp->sd_ail_lock);
627 list_for_each_entry(tr, &sdp->sd_ail1_list, tr_list) {
628 list_for_each_entry_safe(bd, tmp, &tr->tr_ail2_list, bd_ail_st_list) {
629 if (max_revokes == 0)
630 goto out_of_blocks;
631 if (!list_empty(&bd->bd_list))
632 continue;
633 gfs2_add_revoke(sdp, bd);
634 max_revokes--;
635 }
636 }
637out_of_blocks:
638 spin_unlock(&sdp->sd_ail_lock);
639 gfs2_log_unlock(sdp);
640
641 if (!sdp->sd_log_num_revoke) {
642 atomic_inc(&sdp->sd_log_blks_free);
643 if (!sdp->sd_log_blks_reserved)
644 atomic_inc(&sdp->sd_log_blks_free);
645 }
646}
647
648/**
649 * log_write_header - Get and initialize a journal header buffer
650 * @sdp: The GFS2 superblock
651 *
652 * Returns: the initialized log buffer descriptor
653 */
654
655static void log_write_header(struct gfs2_sbd *sdp, u32 flags)
656{
657 struct gfs2_log_header *lh;
658 unsigned int tail;
659 u32 hash;
660 int rw = WRITE_FLUSH_FUA | REQ_META;
661 struct page *page = mempool_alloc(gfs2_page_pool, GFP_NOIO);
662 enum gfs2_freeze_state state = atomic_read(&sdp->sd_freeze_state);
663 lh = page_address(page);
664 clear_page(lh);
665
666 gfs2_assert_withdraw(sdp, (state != SFS_FROZEN));
667
668 tail = current_tail(sdp);
669
670 lh->lh_header.mh_magic = cpu_to_be32(GFS2_MAGIC);
671 lh->lh_header.mh_type = cpu_to_be32(GFS2_METATYPE_LH);
672 lh->lh_header.__pad0 = cpu_to_be64(0);
673 lh->lh_header.mh_format = cpu_to_be32(GFS2_FORMAT_LH);
674 lh->lh_header.mh_jid = cpu_to_be32(sdp->sd_jdesc->jd_jid);
675 lh->lh_sequence = cpu_to_be64(sdp->sd_log_sequence++);
676 lh->lh_flags = cpu_to_be32(flags);
677 lh->lh_tail = cpu_to_be32(tail);
678 lh->lh_blkno = cpu_to_be32(sdp->sd_log_flush_head);
679 hash = gfs2_disk_hash(page_address(page), sizeof(struct gfs2_log_header));
680 lh->lh_hash = cpu_to_be32(hash);
681
682 if (test_bit(SDF_NOBARRIERS, &sdp->sd_flags)) {
683 gfs2_ordered_wait(sdp);
684 log_flush_wait(sdp);
685 rw = WRITE_SYNC | REQ_META | REQ_PRIO;
686 }
687
688 sdp->sd_log_idle = (tail == sdp->sd_log_flush_head);
689 gfs2_log_write_page(sdp, page);
690 gfs2_log_flush_bio(sdp, rw);
691 log_flush_wait(sdp);
692
693 if (sdp->sd_log_tail != tail)
694 log_pull_tail(sdp, tail);
695}
696
697/**
698 * gfs2_log_flush - flush incore transaction(s)
699 * @sdp: the filesystem
700 * @gl: The glock structure to flush. If NULL, flush the whole incore log
701 *
702 */
703
704void gfs2_log_flush(struct gfs2_sbd *sdp, struct gfs2_glock *gl,
705 enum gfs2_flush_type type)
706{
707 struct gfs2_trans *tr;
708 enum gfs2_freeze_state state = atomic_read(&sdp->sd_freeze_state);
709
710 down_write(&sdp->sd_log_flush_lock);
711
712 /* Log might have been flushed while we waited for the flush lock */
713 if (gl && !test_bit(GLF_LFLUSH, &gl->gl_flags)) {
714 up_write(&sdp->sd_log_flush_lock);
715 return;
716 }
717 trace_gfs2_log_flush(sdp, 1);
718
719 if (type == SHUTDOWN_FLUSH)
720 clear_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags);
721
722 sdp->sd_log_flush_head = sdp->sd_log_head;
723 sdp->sd_log_flush_wrapped = 0;
724 tr = sdp->sd_log_tr;
725 if (tr) {
726 sdp->sd_log_tr = NULL;
727 INIT_LIST_HEAD(&tr->tr_ail1_list);
728 INIT_LIST_HEAD(&tr->tr_ail2_list);
729 tr->tr_first = sdp->sd_log_flush_head;
730 if (unlikely (state == SFS_FROZEN))
731 gfs2_assert_withdraw(sdp, !tr->tr_num_buf_new && !tr->tr_num_databuf_new);
732 }
733
734 if (unlikely(state == SFS_FROZEN))
735 gfs2_assert_withdraw(sdp, !sdp->sd_log_num_revoke);
736 gfs2_assert_withdraw(sdp,
737 sdp->sd_log_num_revoke == sdp->sd_log_commited_revoke);
738
739 gfs2_ordered_write(sdp);
740 lops_before_commit(sdp, tr);
741 gfs2_log_flush_bio(sdp, WRITE);
742
743 if (sdp->sd_log_head != sdp->sd_log_flush_head) {
744 log_flush_wait(sdp);
745 log_write_header(sdp, 0);
746 } else if (sdp->sd_log_tail != current_tail(sdp) && !sdp->sd_log_idle){
747 atomic_dec(&sdp->sd_log_blks_free); /* Adjust for unreserved buffer */
748 trace_gfs2_log_blocks(sdp, -1);
749 log_write_header(sdp, 0);
750 }
751 lops_after_commit(sdp, tr);
752
753 gfs2_log_lock(sdp);
754 sdp->sd_log_head = sdp->sd_log_flush_head;
755 sdp->sd_log_blks_reserved = 0;
756 sdp->sd_log_commited_revoke = 0;
757
758 spin_lock(&sdp->sd_ail_lock);
759 if (tr && !list_empty(&tr->tr_ail1_list)) {
760 list_add(&tr->tr_list, &sdp->sd_ail1_list);
761 tr = NULL;
762 }
763 spin_unlock(&sdp->sd_ail_lock);
764 gfs2_log_unlock(sdp);
765
766 if (type != NORMAL_FLUSH) {
767 if (!sdp->sd_log_idle) {
768 for (;;) {
769 gfs2_ail1_start(sdp);
770 gfs2_ail1_wait(sdp);
771 if (gfs2_ail1_empty(sdp))
772 break;
773 }
774 atomic_dec(&sdp->sd_log_blks_free); /* Adjust for unreserved buffer */
775 trace_gfs2_log_blocks(sdp, -1);
776 sdp->sd_log_flush_wrapped = 0;
777 log_write_header(sdp, 0);
778 sdp->sd_log_head = sdp->sd_log_flush_head;
779 }
780 if (type == SHUTDOWN_FLUSH || type == FREEZE_FLUSH)
781 gfs2_log_shutdown(sdp);
782 if (type == FREEZE_FLUSH)
783 atomic_set(&sdp->sd_freeze_state, SFS_FROZEN);
784 }
785
786 trace_gfs2_log_flush(sdp, 0);
787 up_write(&sdp->sd_log_flush_lock);
788
789 kfree(tr);
790}
791
792/**
793 * gfs2_merge_trans - Merge a new transaction into a cached transaction
794 * @old: Original transaction to be expanded
795 * @new: New transaction to be merged
796 */
797
798static void gfs2_merge_trans(struct gfs2_trans *old, struct gfs2_trans *new)
799{
800 WARN_ON_ONCE(old->tr_attached != 1);
801
802 old->tr_num_buf_new += new->tr_num_buf_new;
803 old->tr_num_databuf_new += new->tr_num_databuf_new;
804 old->tr_num_buf_rm += new->tr_num_buf_rm;
805 old->tr_num_databuf_rm += new->tr_num_databuf_rm;
806 old->tr_num_revoke += new->tr_num_revoke;
807 old->tr_num_revoke_rm += new->tr_num_revoke_rm;
808
809 list_splice_tail_init(&new->tr_databuf, &old->tr_databuf);
810 list_splice_tail_init(&new->tr_buf, &old->tr_buf);
811}
812
813static void log_refund(struct gfs2_sbd *sdp, struct gfs2_trans *tr)
814{
815 unsigned int reserved;
816 unsigned int unused;
817 unsigned int maxres;
818
819 gfs2_log_lock(sdp);
820
821 if (sdp->sd_log_tr) {
822 gfs2_merge_trans(sdp->sd_log_tr, tr);
823 } else if (tr->tr_num_buf_new || tr->tr_num_databuf_new) {
824 gfs2_assert_withdraw(sdp, tr->tr_alloced);
825 sdp->sd_log_tr = tr;
826 tr->tr_attached = 1;
827 }
828
829 sdp->sd_log_commited_revoke += tr->tr_num_revoke - tr->tr_num_revoke_rm;
830 reserved = calc_reserved(sdp);
831 maxres = sdp->sd_log_blks_reserved + tr->tr_reserved;
832 gfs2_assert_withdraw(sdp, maxres >= reserved);
833 unused = maxres - reserved;
834 atomic_add(unused, &sdp->sd_log_blks_free);
835 trace_gfs2_log_blocks(sdp, unused);
836 gfs2_assert_withdraw(sdp, atomic_read(&sdp->sd_log_blks_free) <=
837 sdp->sd_jdesc->jd_blocks);
838 sdp->sd_log_blks_reserved = reserved;
839
840 gfs2_log_unlock(sdp);
841}
842
843/**
844 * gfs2_log_commit - Commit a transaction to the log
845 * @sdp: the filesystem
846 * @tr: the transaction
847 *
848 * We wake up gfs2_logd if the number of pinned blocks exceed thresh1
849 * or the total number of used blocks (pinned blocks plus AIL blocks)
850 * is greater than thresh2.
851 *
852 * At mount time thresh1 is 1/3rd of journal size, thresh2 is 2/3rd of
853 * journal size.
854 *
855 * Returns: errno
856 */
857
858void gfs2_log_commit(struct gfs2_sbd *sdp, struct gfs2_trans *tr)
859{
860 log_refund(sdp, tr);
861
862 if (atomic_read(&sdp->sd_log_pinned) > atomic_read(&sdp->sd_log_thresh1) ||
863 ((sdp->sd_jdesc->jd_blocks - atomic_read(&sdp->sd_log_blks_free)) >
864 atomic_read(&sdp->sd_log_thresh2)))
865 wake_up(&sdp->sd_logd_waitq);
866}
867
868/**
869 * gfs2_log_shutdown - write a shutdown header into a journal
870 * @sdp: the filesystem
871 *
872 */
873
874void gfs2_log_shutdown(struct gfs2_sbd *sdp)
875{
876 gfs2_assert_withdraw(sdp, !sdp->sd_log_blks_reserved);
877 gfs2_assert_withdraw(sdp, !sdp->sd_log_num_revoke);
878 gfs2_assert_withdraw(sdp, list_empty(&sdp->sd_ail1_list));
879
880 sdp->sd_log_flush_head = sdp->sd_log_head;
881 sdp->sd_log_flush_wrapped = 0;
882
883 log_write_header(sdp, GFS2_LOG_HEAD_UNMOUNT);
884
885 gfs2_assert_warn(sdp, sdp->sd_log_head == sdp->sd_log_tail);
886 gfs2_assert_warn(sdp, list_empty(&sdp->sd_ail2_list));
887
888 sdp->sd_log_head = sdp->sd_log_flush_head;
889 sdp->sd_log_tail = sdp->sd_log_head;
890}
891
892static inline int gfs2_jrnl_flush_reqd(struct gfs2_sbd *sdp)
893{
894 return (atomic_read(&sdp->sd_log_pinned) >= atomic_read(&sdp->sd_log_thresh1));
895}
896
897static inline int gfs2_ail_flush_reqd(struct gfs2_sbd *sdp)
898{
899 unsigned int used_blocks = sdp->sd_jdesc->jd_blocks - atomic_read(&sdp->sd_log_blks_free);
900 return used_blocks >= atomic_read(&sdp->sd_log_thresh2);
901}
902
903/**
904 * gfs2_logd - Update log tail as Active Items get flushed to in-place blocks
905 * @sdp: Pointer to GFS2 superblock
906 *
907 * Also, periodically check to make sure that we're using the most recent
908 * journal index.
909 */
910
911int gfs2_logd(void *data)
912{
913 struct gfs2_sbd *sdp = data;
914 unsigned long t = 1;
915 DEFINE_WAIT(wait);
916
917 while (!kthread_should_stop()) {
918
919 if (gfs2_jrnl_flush_reqd(sdp) || t == 0) {
920 gfs2_ail1_empty(sdp);
921 gfs2_log_flush(sdp, NULL, NORMAL_FLUSH);
922 }
923
924 if (gfs2_ail_flush_reqd(sdp)) {
925 gfs2_ail1_start(sdp);
926 gfs2_ail1_wait(sdp);
927 gfs2_ail1_empty(sdp);
928 gfs2_log_flush(sdp, NULL, NORMAL_FLUSH);
929 }
930
931 if (!gfs2_ail_flush_reqd(sdp))
932 wake_up(&sdp->sd_log_waitq);
933
934 t = gfs2_tune_get(sdp, gt_logd_secs) * HZ;
935
936 try_to_freeze();
937
938 do {
939 prepare_to_wait(&sdp->sd_logd_waitq, &wait,
940 TASK_INTERRUPTIBLE);
941 if (!gfs2_ail_flush_reqd(sdp) &&
942 !gfs2_jrnl_flush_reqd(sdp) &&
943 !kthread_should_stop())
944 t = schedule_timeout(t);
945 } while(t && !gfs2_ail_flush_reqd(sdp) &&
946 !gfs2_jrnl_flush_reqd(sdp) &&
947 !kthread_should_stop());
948 finish_wait(&sdp->sd_logd_waitq, &wait);
949 }
950
951 return 0;
952}
953
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
4 * Copyright (C) 2004-2007 Red Hat, Inc. All rights reserved.
5 */
6
7#include <linux/sched.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/delay.h>
16#include <linux/kthread.h>
17#include <linux/freezer.h>
18#include <linux/bio.h>
19#include <linux/blkdev.h>
20#include <linux/writeback.h>
21#include <linux/list_sort.h>
22
23#include "gfs2.h"
24#include "incore.h"
25#include "bmap.h"
26#include "glock.h"
27#include "log.h"
28#include "lops.h"
29#include "meta_io.h"
30#include "util.h"
31#include "dir.h"
32#include "trace_gfs2.h"
33#include "trans.h"
34
35static void gfs2_log_shutdown(struct gfs2_sbd *sdp);
36
37/**
38 * gfs2_struct2blk - compute stuff
39 * @sdp: the filesystem
40 * @nstruct: the number of structures
41 *
42 * Compute the number of log descriptor blocks needed to hold a certain number
43 * of structures of a certain size.
44 *
45 * Returns: the number of blocks needed (minimum is always 1)
46 */
47
48unsigned int gfs2_struct2blk(struct gfs2_sbd *sdp, unsigned int nstruct)
49{
50 unsigned int blks;
51 unsigned int first, second;
52
53 /* The initial struct gfs2_log_descriptor block */
54 blks = 1;
55 first = sdp->sd_ldptrs;
56
57 if (nstruct > first) {
58 /* Subsequent struct gfs2_meta_header blocks */
59 second = sdp->sd_inptrs;
60 blks += DIV_ROUND_UP(nstruct - first, second);
61 }
62
63 return blks;
64}
65
66/**
67 * gfs2_remove_from_ail - Remove an entry from the ail lists, updating counters
68 * @bd: The gfs2_bufdata to remove
69 *
70 * The ail lock _must_ be held when calling this function
71 *
72 */
73
74void gfs2_remove_from_ail(struct gfs2_bufdata *bd)
75{
76 bd->bd_tr = NULL;
77 list_del_init(&bd->bd_ail_st_list);
78 list_del_init(&bd->bd_ail_gl_list);
79 atomic_dec(&bd->bd_gl->gl_ail_count);
80 brelse(bd->bd_bh);
81}
82
83/**
84 * gfs2_ail1_start_one - Start I/O on a transaction
85 * @sdp: The superblock
86 * @wbc: The writeback control structure
87 * @tr: The transaction to start I/O on
88 * @plug: The block plug currently active
89 */
90
91static int gfs2_ail1_start_one(struct gfs2_sbd *sdp,
92 struct writeback_control *wbc,
93 struct gfs2_trans *tr, struct blk_plug *plug)
94__releases(&sdp->sd_ail_lock)
95__acquires(&sdp->sd_ail_lock)
96{
97 struct gfs2_glock *gl = NULL;
98 struct address_space *mapping;
99 struct gfs2_bufdata *bd, *s;
100 struct buffer_head *bh;
101 int ret = 0;
102
103 list_for_each_entry_safe_reverse(bd, s, &tr->tr_ail1_list, bd_ail_st_list) {
104 bh = bd->bd_bh;
105
106 gfs2_assert(sdp, bd->bd_tr == tr);
107
108 if (!buffer_busy(bh)) {
109 if (buffer_uptodate(bh)) {
110 list_move(&bd->bd_ail_st_list,
111 &tr->tr_ail2_list);
112 continue;
113 }
114 if (!cmpxchg(&sdp->sd_log_error, 0, -EIO)) {
115 gfs2_io_error_bh(sdp, bh);
116 gfs2_withdraw_delayed(sdp);
117 }
118 }
119
120 if (gfs2_withdrawing_or_withdrawn(sdp)) {
121 gfs2_remove_from_ail(bd);
122 continue;
123 }
124 if (!buffer_dirty(bh))
125 continue;
126 if (gl == bd->bd_gl)
127 continue;
128 gl = bd->bd_gl;
129 list_move(&bd->bd_ail_st_list, &tr->tr_ail1_list);
130 mapping = bh->b_folio->mapping;
131 if (!mapping)
132 continue;
133 spin_unlock(&sdp->sd_ail_lock);
134 ret = mapping->a_ops->writepages(mapping, wbc);
135 if (need_resched()) {
136 blk_finish_plug(plug);
137 cond_resched();
138 blk_start_plug(plug);
139 }
140 spin_lock(&sdp->sd_ail_lock);
141 if (ret == -ENODATA) /* if a jdata write into a new hole */
142 ret = 0; /* ignore it */
143 mapping_set_error(mapping, ret);
144 if (ret || wbc->nr_to_write <= 0)
145 break;
146 return -EBUSY;
147 }
148
149 return ret;
150}
151
152static void dump_ail_list(struct gfs2_sbd *sdp)
153{
154 struct gfs2_trans *tr;
155 struct gfs2_bufdata *bd;
156 struct buffer_head *bh;
157
158 list_for_each_entry_reverse(tr, &sdp->sd_ail1_list, tr_list) {
159 list_for_each_entry_reverse(bd, &tr->tr_ail1_list,
160 bd_ail_st_list) {
161 bh = bd->bd_bh;
162 fs_err(sdp, "bd %p: blk:0x%llx bh=%p ", bd,
163 (unsigned long long)bd->bd_blkno, bh);
164 if (!bh) {
165 fs_err(sdp, "\n");
166 continue;
167 }
168 fs_err(sdp, "0x%llx up2:%d dirt:%d lkd:%d req:%d "
169 "map:%d new:%d ar:%d aw:%d delay:%d "
170 "io err:%d unwritten:%d dfr:%d pin:%d esc:%d\n",
171 (unsigned long long)bh->b_blocknr,
172 buffer_uptodate(bh), buffer_dirty(bh),
173 buffer_locked(bh), buffer_req(bh),
174 buffer_mapped(bh), buffer_new(bh),
175 buffer_async_read(bh), buffer_async_write(bh),
176 buffer_delay(bh), buffer_write_io_error(bh),
177 buffer_unwritten(bh),
178 buffer_defer_completion(bh),
179 buffer_pinned(bh), buffer_escaped(bh));
180 }
181 }
182}
183
184/**
185 * gfs2_ail1_flush - start writeback of some ail1 entries
186 * @sdp: The super block
187 * @wbc: The writeback control structure
188 *
189 * Writes back some ail1 entries, according to the limits in the
190 * writeback control structure
191 */
192
193void gfs2_ail1_flush(struct gfs2_sbd *sdp, struct writeback_control *wbc)
194{
195 struct list_head *head = &sdp->sd_ail1_list;
196 struct gfs2_trans *tr;
197 struct blk_plug plug;
198 int ret;
199 unsigned long flush_start = jiffies;
200
201 trace_gfs2_ail_flush(sdp, wbc, 1);
202 blk_start_plug(&plug);
203 spin_lock(&sdp->sd_ail_lock);
204restart:
205 ret = 0;
206 if (time_after(jiffies, flush_start + (HZ * 600))) {
207 fs_err(sdp, "Error: In %s for ten minutes! t=%d\n",
208 __func__, current->journal_info ? 1 : 0);
209 dump_ail_list(sdp);
210 goto out;
211 }
212 list_for_each_entry_reverse(tr, head, tr_list) {
213 if (wbc->nr_to_write <= 0)
214 break;
215 ret = gfs2_ail1_start_one(sdp, wbc, tr, &plug);
216 if (ret) {
217 if (ret == -EBUSY)
218 goto restart;
219 break;
220 }
221 }
222out:
223 spin_unlock(&sdp->sd_ail_lock);
224 blk_finish_plug(&plug);
225 if (ret) {
226 gfs2_lm(sdp, "gfs2_ail1_start_one returned: %d\n", ret);
227 gfs2_withdraw(sdp);
228 }
229 trace_gfs2_ail_flush(sdp, wbc, 0);
230}
231
232/**
233 * gfs2_ail1_start - start writeback of all ail1 entries
234 * @sdp: The superblock
235 */
236
237static void gfs2_ail1_start(struct gfs2_sbd *sdp)
238{
239 struct writeback_control wbc = {
240 .sync_mode = WB_SYNC_NONE,
241 .nr_to_write = LONG_MAX,
242 .range_start = 0,
243 .range_end = LLONG_MAX,
244 };
245
246 return gfs2_ail1_flush(sdp, &wbc);
247}
248
249static void gfs2_log_update_flush_tail(struct gfs2_sbd *sdp)
250{
251 unsigned int new_flush_tail = sdp->sd_log_head;
252 struct gfs2_trans *tr;
253
254 if (!list_empty(&sdp->sd_ail1_list)) {
255 tr = list_last_entry(&sdp->sd_ail1_list,
256 struct gfs2_trans, tr_list);
257 new_flush_tail = tr->tr_first;
258 }
259 sdp->sd_log_flush_tail = new_flush_tail;
260}
261
262static void gfs2_log_update_head(struct gfs2_sbd *sdp)
263{
264 unsigned int new_head = sdp->sd_log_flush_head;
265
266 if (sdp->sd_log_flush_tail == sdp->sd_log_head)
267 sdp->sd_log_flush_tail = new_head;
268 sdp->sd_log_head = new_head;
269}
270
271/*
272 * gfs2_ail_empty_tr - empty one of the ail lists of a transaction
273 */
274
275static void gfs2_ail_empty_tr(struct gfs2_sbd *sdp, struct gfs2_trans *tr,
276 struct list_head *head)
277{
278 struct gfs2_bufdata *bd;
279
280 while (!list_empty(head)) {
281 bd = list_first_entry(head, struct gfs2_bufdata,
282 bd_ail_st_list);
283 gfs2_assert(sdp, bd->bd_tr == tr);
284 gfs2_remove_from_ail(bd);
285 }
286}
287
288/**
289 * gfs2_ail1_empty_one - Check whether or not a trans in the AIL has been synced
290 * @sdp: the filesystem
291 * @tr: the transaction
292 * @max_revokes: If nonzero, issue revokes for the bd items for written buffers
293 *
294 * returns: the transaction's count of remaining active items
295 */
296
297static int gfs2_ail1_empty_one(struct gfs2_sbd *sdp, struct gfs2_trans *tr,
298 int *max_revokes)
299{
300 struct gfs2_bufdata *bd, *s;
301 struct buffer_head *bh;
302 int active_count = 0;
303
304 list_for_each_entry_safe_reverse(bd, s, &tr->tr_ail1_list,
305 bd_ail_st_list) {
306 bh = bd->bd_bh;
307 gfs2_assert(sdp, bd->bd_tr == tr);
308 /*
309 * If another process flagged an io error, e.g. writing to the
310 * journal, error all other bhs and move them off the ail1 to
311 * prevent a tight loop when unmount tries to flush ail1,
312 * regardless of whether they're still busy. If no outside
313 * errors were found and the buffer is busy, move to the next.
314 * If the ail buffer is not busy and caught an error, flag it
315 * for others.
316 */
317 if (!sdp->sd_log_error && buffer_busy(bh)) {
318 active_count++;
319 continue;
320 }
321 if (!buffer_uptodate(bh) &&
322 !cmpxchg(&sdp->sd_log_error, 0, -EIO)) {
323 gfs2_io_error_bh(sdp, bh);
324 gfs2_withdraw_delayed(sdp);
325 }
326 /*
327 * If we have space for revokes and the bd is no longer on any
328 * buf list, we can just add a revoke for it immediately and
329 * avoid having to put it on the ail2 list, where it would need
330 * to be revoked later.
331 */
332 if (*max_revokes && list_empty(&bd->bd_list)) {
333 gfs2_add_revoke(sdp, bd);
334 (*max_revokes)--;
335 continue;
336 }
337 list_move(&bd->bd_ail_st_list, &tr->tr_ail2_list);
338 }
339 return active_count;
340}
341
342/**
343 * gfs2_ail1_empty - Try to empty the ail1 lists
344 * @sdp: The superblock
345 * @max_revokes: If non-zero, add revokes where appropriate
346 *
347 * Tries to empty the ail1 lists, starting with the oldest first.
348 * Returns %true if the ail1 list is now empty.
349 */
350
351static bool gfs2_ail1_empty(struct gfs2_sbd *sdp, int max_revokes)
352{
353 struct gfs2_trans *tr, *s;
354 int oldest_tr = 1;
355 bool empty;
356
357 spin_lock(&sdp->sd_ail_lock);
358 list_for_each_entry_safe_reverse(tr, s, &sdp->sd_ail1_list, tr_list) {
359 if (!gfs2_ail1_empty_one(sdp, tr, &max_revokes) && oldest_tr)
360 list_move(&tr->tr_list, &sdp->sd_ail2_list);
361 else
362 oldest_tr = 0;
363 }
364 gfs2_log_update_flush_tail(sdp);
365 empty = list_empty(&sdp->sd_ail1_list);
366 spin_unlock(&sdp->sd_ail_lock);
367
368 return empty;
369}
370
371static void gfs2_ail1_wait(struct gfs2_sbd *sdp)
372{
373 struct gfs2_trans *tr;
374 struct gfs2_bufdata *bd;
375 struct buffer_head *bh;
376
377 spin_lock(&sdp->sd_ail_lock);
378 list_for_each_entry_reverse(tr, &sdp->sd_ail1_list, tr_list) {
379 list_for_each_entry(bd, &tr->tr_ail1_list, bd_ail_st_list) {
380 bh = bd->bd_bh;
381 if (!buffer_locked(bh))
382 continue;
383 get_bh(bh);
384 spin_unlock(&sdp->sd_ail_lock);
385 wait_on_buffer(bh);
386 brelse(bh);
387 return;
388 }
389 }
390 spin_unlock(&sdp->sd_ail_lock);
391}
392
393static void __ail2_empty(struct gfs2_sbd *sdp, struct gfs2_trans *tr)
394{
395 gfs2_ail_empty_tr(sdp, tr, &tr->tr_ail2_list);
396 list_del(&tr->tr_list);
397 gfs2_assert_warn(sdp, list_empty(&tr->tr_ail1_list));
398 gfs2_assert_warn(sdp, list_empty(&tr->tr_ail2_list));
399 gfs2_trans_free(sdp, tr);
400}
401
402static void ail2_empty(struct gfs2_sbd *sdp, unsigned int new_tail)
403{
404 struct list_head *ail2_list = &sdp->sd_ail2_list;
405 unsigned int old_tail = sdp->sd_log_tail;
406 struct gfs2_trans *tr, *safe;
407
408 spin_lock(&sdp->sd_ail_lock);
409 if (old_tail <= new_tail) {
410 list_for_each_entry_safe(tr, safe, ail2_list, tr_list) {
411 if (old_tail <= tr->tr_first && tr->tr_first < new_tail)
412 __ail2_empty(sdp, tr);
413 }
414 } else {
415 list_for_each_entry_safe(tr, safe, ail2_list, tr_list) {
416 if (old_tail <= tr->tr_first || tr->tr_first < new_tail)
417 __ail2_empty(sdp, tr);
418 }
419 }
420 spin_unlock(&sdp->sd_ail_lock);
421}
422
423/**
424 * gfs2_log_is_empty - Check if the log is empty
425 * @sdp: The GFS2 superblock
426 */
427
428bool gfs2_log_is_empty(struct gfs2_sbd *sdp) {
429 return atomic_read(&sdp->sd_log_blks_free) == sdp->sd_jdesc->jd_blocks;
430}
431
432static bool __gfs2_log_try_reserve_revokes(struct gfs2_sbd *sdp, unsigned int revokes)
433{
434 unsigned int available;
435
436 available = atomic_read(&sdp->sd_log_revokes_available);
437 while (available >= revokes) {
438 if (atomic_try_cmpxchg(&sdp->sd_log_revokes_available,
439 &available, available - revokes))
440 return true;
441 }
442 return false;
443}
444
445/**
446 * gfs2_log_release_revokes - Release a given number of revokes
447 * @sdp: The GFS2 superblock
448 * @revokes: The number of revokes to release
449 *
450 * sdp->sd_log_flush_lock must be held.
451 */
452void gfs2_log_release_revokes(struct gfs2_sbd *sdp, unsigned int revokes)
453{
454 if (revokes)
455 atomic_add(revokes, &sdp->sd_log_revokes_available);
456}
457
458/**
459 * gfs2_log_release - Release a given number of log blocks
460 * @sdp: The GFS2 superblock
461 * @blks: The number of blocks
462 *
463 */
464
465void gfs2_log_release(struct gfs2_sbd *sdp, unsigned int blks)
466{
467 atomic_add(blks, &sdp->sd_log_blks_free);
468 trace_gfs2_log_blocks(sdp, blks);
469 gfs2_assert_withdraw(sdp, atomic_read(&sdp->sd_log_blks_free) <=
470 sdp->sd_jdesc->jd_blocks);
471 if (atomic_read(&sdp->sd_log_blks_needed))
472 wake_up(&sdp->sd_log_waitq);
473}
474
475/**
476 * __gfs2_log_try_reserve - Try to make a log reservation
477 * @sdp: The GFS2 superblock
478 * @blks: The number of blocks to reserve
479 * @taboo_blks: The number of blocks to leave free
480 *
481 * Try to do the same as __gfs2_log_reserve(), but fail if no more log
482 * space is immediately available.
483 */
484static bool __gfs2_log_try_reserve(struct gfs2_sbd *sdp, unsigned int blks,
485 unsigned int taboo_blks)
486{
487 unsigned wanted = blks + taboo_blks;
488 unsigned int free_blocks;
489
490 free_blocks = atomic_read(&sdp->sd_log_blks_free);
491 while (free_blocks >= wanted) {
492 if (atomic_try_cmpxchg(&sdp->sd_log_blks_free, &free_blocks,
493 free_blocks - blks)) {
494 trace_gfs2_log_blocks(sdp, -blks);
495 return true;
496 }
497 }
498 return false;
499}
500
501/**
502 * __gfs2_log_reserve - Make a log reservation
503 * @sdp: The GFS2 superblock
504 * @blks: The number of blocks to reserve
505 * @taboo_blks: The number of blocks to leave free
506 *
507 * @taboo_blks is set to 0 for logd, and to GFS2_LOG_FLUSH_MIN_BLOCKS
508 * for all other processes. This ensures that when the log is almost full,
509 * logd will still be able to call gfs2_log_flush one more time without
510 * blocking, which will advance the tail and make some more log space
511 * available.
512 *
513 * We no longer flush the log here, instead we wake up logd to do that
514 * for us. To avoid the thundering herd and to ensure that we deal fairly
515 * with queued waiters, we use an exclusive wait. This means that when we
516 * get woken with enough journal space to get our reservation, we need to
517 * wake the next waiter on the list.
518 */
519
520static void __gfs2_log_reserve(struct gfs2_sbd *sdp, unsigned int blks,
521 unsigned int taboo_blks)
522{
523 unsigned wanted = blks + taboo_blks;
524 unsigned int free_blocks;
525
526 atomic_add(blks, &sdp->sd_log_blks_needed);
527 for (;;) {
528 if (current != sdp->sd_logd_process)
529 wake_up(&sdp->sd_logd_waitq);
530 io_wait_event(sdp->sd_log_waitq,
531 (free_blocks = atomic_read(&sdp->sd_log_blks_free),
532 free_blocks >= wanted));
533 do {
534 if (atomic_try_cmpxchg(&sdp->sd_log_blks_free,
535 &free_blocks,
536 free_blocks - blks))
537 goto reserved;
538 } while (free_blocks >= wanted);
539 }
540
541reserved:
542 trace_gfs2_log_blocks(sdp, -blks);
543 if (atomic_sub_return(blks, &sdp->sd_log_blks_needed))
544 wake_up(&sdp->sd_log_waitq);
545}
546
547/**
548 * gfs2_log_try_reserve - Try to make a log reservation
549 * @sdp: The GFS2 superblock
550 * @tr: The transaction
551 * @extra_revokes: The number of additional revokes reserved (output)
552 *
553 * This is similar to gfs2_log_reserve, but sdp->sd_log_flush_lock must be
554 * held for correct revoke accounting.
555 */
556
557bool gfs2_log_try_reserve(struct gfs2_sbd *sdp, struct gfs2_trans *tr,
558 unsigned int *extra_revokes)
559{
560 unsigned int blks = tr->tr_reserved;
561 unsigned int revokes = tr->tr_revokes;
562 unsigned int revoke_blks = 0;
563
564 *extra_revokes = 0;
565 if (revokes && !__gfs2_log_try_reserve_revokes(sdp, revokes)) {
566 revoke_blks = DIV_ROUND_UP(revokes, sdp->sd_inptrs);
567 *extra_revokes = revoke_blks * sdp->sd_inptrs - revokes;
568 blks += revoke_blks;
569 }
570 if (!blks)
571 return true;
572 if (__gfs2_log_try_reserve(sdp, blks, GFS2_LOG_FLUSH_MIN_BLOCKS))
573 return true;
574 if (!revoke_blks)
575 gfs2_log_release_revokes(sdp, revokes);
576 return false;
577}
578
579/**
580 * gfs2_log_reserve - Make a log reservation
581 * @sdp: The GFS2 superblock
582 * @tr: The transaction
583 * @extra_revokes: The number of additional revokes reserved (output)
584 *
585 * sdp->sd_log_flush_lock must not be held.
586 */
587
588void gfs2_log_reserve(struct gfs2_sbd *sdp, struct gfs2_trans *tr,
589 unsigned int *extra_revokes)
590{
591 unsigned int blks = tr->tr_reserved;
592 unsigned int revokes = tr->tr_revokes;
593 unsigned int revoke_blks;
594
595 *extra_revokes = 0;
596 if (revokes) {
597 revoke_blks = DIV_ROUND_UP(revokes, sdp->sd_inptrs);
598 *extra_revokes = revoke_blks * sdp->sd_inptrs - revokes;
599 blks += revoke_blks;
600 }
601 __gfs2_log_reserve(sdp, blks, GFS2_LOG_FLUSH_MIN_BLOCKS);
602}
603
604/**
605 * log_distance - Compute distance between two journal blocks
606 * @sdp: The GFS2 superblock
607 * @newer: The most recent journal block of the pair
608 * @older: The older journal block of the pair
609 *
610 * Compute the distance (in the journal direction) between two
611 * blocks in the journal
612 *
613 * Returns: the distance in blocks
614 */
615
616static inline unsigned int log_distance(struct gfs2_sbd *sdp, unsigned int newer,
617 unsigned int older)
618{
619 int dist;
620
621 dist = newer - older;
622 if (dist < 0)
623 dist += sdp->sd_jdesc->jd_blocks;
624
625 return dist;
626}
627
628/**
629 * calc_reserved - Calculate the number of blocks to keep reserved
630 * @sdp: The GFS2 superblock
631 *
632 * This is complex. We need to reserve room for all our currently used
633 * metadata blocks (e.g. normal file I/O rewriting file time stamps) and
634 * all our journaled data blocks for journaled files (e.g. files in the
635 * meta_fs like rindex, or files for which chattr +j was done.)
636 * If we don't reserve enough space, corruption will follow.
637 *
638 * We can have metadata blocks and jdata blocks in the same journal. Each
639 * type gets its own log descriptor, for which we need to reserve a block.
640 * In fact, each type has the potential for needing more than one log descriptor
641 * in cases where we have more blocks than will fit in a log descriptor.
642 * Metadata journal entries take up half the space of journaled buffer entries.
643 *
644 * Also, we need to reserve blocks for revoke journal entries and one for an
645 * overall header for the lot.
646 *
647 * Returns: the number of blocks reserved
648 */
649static unsigned int calc_reserved(struct gfs2_sbd *sdp)
650{
651 unsigned int reserved = GFS2_LOG_FLUSH_MIN_BLOCKS;
652 unsigned int blocks;
653 struct gfs2_trans *tr = sdp->sd_log_tr;
654
655 if (tr) {
656 blocks = tr->tr_num_buf_new - tr->tr_num_buf_rm;
657 reserved += blocks + DIV_ROUND_UP(blocks, buf_limit(sdp));
658 blocks = tr->tr_num_databuf_new - tr->tr_num_databuf_rm;
659 reserved += blocks + DIV_ROUND_UP(blocks, databuf_limit(sdp));
660 }
661 return reserved;
662}
663
664static void log_pull_tail(struct gfs2_sbd *sdp)
665{
666 unsigned int new_tail = sdp->sd_log_flush_tail;
667 unsigned int dist;
668
669 if (new_tail == sdp->sd_log_tail)
670 return;
671 dist = log_distance(sdp, new_tail, sdp->sd_log_tail);
672 ail2_empty(sdp, new_tail);
673 gfs2_log_release(sdp, dist);
674 sdp->sd_log_tail = new_tail;
675}
676
677
678void log_flush_wait(struct gfs2_sbd *sdp)
679{
680 DEFINE_WAIT(wait);
681
682 if (atomic_read(&sdp->sd_log_in_flight)) {
683 do {
684 prepare_to_wait(&sdp->sd_log_flush_wait, &wait,
685 TASK_UNINTERRUPTIBLE);
686 if (atomic_read(&sdp->sd_log_in_flight))
687 io_schedule();
688 } while(atomic_read(&sdp->sd_log_in_flight));
689 finish_wait(&sdp->sd_log_flush_wait, &wait);
690 }
691}
692
693static int ip_cmp(void *priv, const struct list_head *a, const struct list_head *b)
694{
695 struct gfs2_inode *ipa, *ipb;
696
697 ipa = list_entry(a, struct gfs2_inode, i_ordered);
698 ipb = list_entry(b, struct gfs2_inode, i_ordered);
699
700 if (ipa->i_no_addr < ipb->i_no_addr)
701 return -1;
702 if (ipa->i_no_addr > ipb->i_no_addr)
703 return 1;
704 return 0;
705}
706
707static void __ordered_del_inode(struct gfs2_inode *ip)
708{
709 if (!list_empty(&ip->i_ordered))
710 list_del_init(&ip->i_ordered);
711}
712
713static void gfs2_ordered_write(struct gfs2_sbd *sdp)
714{
715 struct gfs2_inode *ip;
716 LIST_HEAD(written);
717
718 spin_lock(&sdp->sd_ordered_lock);
719 list_sort(NULL, &sdp->sd_log_ordered, &ip_cmp);
720 while (!list_empty(&sdp->sd_log_ordered)) {
721 ip = list_first_entry(&sdp->sd_log_ordered, struct gfs2_inode, i_ordered);
722 if (ip->i_inode.i_mapping->nrpages == 0) {
723 __ordered_del_inode(ip);
724 continue;
725 }
726 list_move(&ip->i_ordered, &written);
727 spin_unlock(&sdp->sd_ordered_lock);
728 filemap_fdatawrite(ip->i_inode.i_mapping);
729 spin_lock(&sdp->sd_ordered_lock);
730 }
731 list_splice(&written, &sdp->sd_log_ordered);
732 spin_unlock(&sdp->sd_ordered_lock);
733}
734
735static void gfs2_ordered_wait(struct gfs2_sbd *sdp)
736{
737 struct gfs2_inode *ip;
738
739 spin_lock(&sdp->sd_ordered_lock);
740 while (!list_empty(&sdp->sd_log_ordered)) {
741 ip = list_first_entry(&sdp->sd_log_ordered, struct gfs2_inode, i_ordered);
742 __ordered_del_inode(ip);
743 if (ip->i_inode.i_mapping->nrpages == 0)
744 continue;
745 spin_unlock(&sdp->sd_ordered_lock);
746 filemap_fdatawait(ip->i_inode.i_mapping);
747 spin_lock(&sdp->sd_ordered_lock);
748 }
749 spin_unlock(&sdp->sd_ordered_lock);
750}
751
752void gfs2_ordered_del_inode(struct gfs2_inode *ip)
753{
754 struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
755
756 spin_lock(&sdp->sd_ordered_lock);
757 __ordered_del_inode(ip);
758 spin_unlock(&sdp->sd_ordered_lock);
759}
760
761void gfs2_add_revoke(struct gfs2_sbd *sdp, struct gfs2_bufdata *bd)
762{
763 struct buffer_head *bh = bd->bd_bh;
764 struct gfs2_glock *gl = bd->bd_gl;
765
766 sdp->sd_log_num_revoke++;
767 if (atomic_inc_return(&gl->gl_revokes) == 1)
768 gfs2_glock_hold(gl);
769 bh->b_private = NULL;
770 bd->bd_blkno = bh->b_blocknr;
771 gfs2_remove_from_ail(bd); /* drops ref on bh */
772 bd->bd_bh = NULL;
773 set_bit(GLF_LFLUSH, &gl->gl_flags);
774 list_add(&bd->bd_list, &sdp->sd_log_revokes);
775}
776
777void gfs2_glock_remove_revoke(struct gfs2_glock *gl)
778{
779 if (atomic_dec_return(&gl->gl_revokes) == 0) {
780 clear_bit(GLF_LFLUSH, &gl->gl_flags);
781 gfs2_glock_put_async(gl);
782 }
783}
784
785/**
786 * gfs2_flush_revokes - Add as many revokes to the system transaction as we can
787 * @sdp: The GFS2 superblock
788 *
789 * Our usual strategy is to defer writing revokes as much as we can in the hope
790 * that we'll eventually overwrite the journal, which will make those revokes
791 * go away. This changes when we flush the log: at that point, there will
792 * likely be some left-over space in the last revoke block of that transaction.
793 * We can fill that space with additional revokes for blocks that have already
794 * been written back. This will basically come at no cost now, and will save
795 * us from having to keep track of those blocks on the AIL2 list later.
796 */
797void gfs2_flush_revokes(struct gfs2_sbd *sdp)
798{
799 /* number of revokes we still have room for */
800 unsigned int max_revokes = atomic_read(&sdp->sd_log_revokes_available);
801
802 gfs2_log_lock(sdp);
803 gfs2_ail1_empty(sdp, max_revokes);
804 gfs2_log_unlock(sdp);
805
806 if (gfs2_withdrawing(sdp))
807 gfs2_withdraw(sdp);
808}
809
810/**
811 * gfs2_write_log_header - Write a journal log header buffer at lblock
812 * @sdp: The GFS2 superblock
813 * @jd: journal descriptor of the journal to which we are writing
814 * @seq: sequence number
815 * @tail: tail of the log
816 * @lblock: value for lh_blkno (block number relative to start of journal)
817 * @flags: log header flags GFS2_LOG_HEAD_*
818 * @op_flags: flags to pass to the bio
819 *
820 * Returns: the initialized log buffer descriptor
821 */
822
823void gfs2_write_log_header(struct gfs2_sbd *sdp, struct gfs2_jdesc *jd,
824 u64 seq, u32 tail, u32 lblock, u32 flags,
825 blk_opf_t op_flags)
826{
827 struct gfs2_log_header *lh;
828 u32 hash, crc;
829 struct page *page;
830 struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
831 struct timespec64 tv;
832 struct super_block *sb = sdp->sd_vfs;
833 u64 dblock;
834
835 if (gfs2_withdrawing_or_withdrawn(sdp))
836 return;
837
838 page = mempool_alloc(gfs2_page_pool, GFP_NOIO);
839 lh = page_address(page);
840 clear_page(lh);
841
842 lh->lh_header.mh_magic = cpu_to_be32(GFS2_MAGIC);
843 lh->lh_header.mh_type = cpu_to_be32(GFS2_METATYPE_LH);
844 lh->lh_header.__pad0 = cpu_to_be64(0);
845 lh->lh_header.mh_format = cpu_to_be32(GFS2_FORMAT_LH);
846 lh->lh_header.mh_jid = cpu_to_be32(sdp->sd_jdesc->jd_jid);
847 lh->lh_sequence = cpu_to_be64(seq);
848 lh->lh_flags = cpu_to_be32(flags);
849 lh->lh_tail = cpu_to_be32(tail);
850 lh->lh_blkno = cpu_to_be32(lblock);
851 hash = ~crc32(~0, lh, LH_V1_SIZE);
852 lh->lh_hash = cpu_to_be32(hash);
853
854 ktime_get_coarse_real_ts64(&tv);
855 lh->lh_nsec = cpu_to_be32(tv.tv_nsec);
856 lh->lh_sec = cpu_to_be64(tv.tv_sec);
857 if (!list_empty(&jd->extent_list))
858 dblock = gfs2_log_bmap(jd, lblock);
859 else {
860 unsigned int extlen;
861 int ret;
862
863 extlen = 1;
864 ret = gfs2_get_extent(jd->jd_inode, lblock, &dblock, &extlen);
865 if (gfs2_assert_withdraw(sdp, ret == 0))
866 return;
867 }
868 lh->lh_addr = cpu_to_be64(dblock);
869 lh->lh_jinode = cpu_to_be64(GFS2_I(jd->jd_inode)->i_no_addr);
870
871 /* We may only write local statfs, quota, etc., when writing to our
872 own journal. The values are left 0 when recovering a journal
873 different from our own. */
874 if (!(flags & GFS2_LOG_HEAD_RECOVERY)) {
875 lh->lh_statfs_addr =
876 cpu_to_be64(GFS2_I(sdp->sd_sc_inode)->i_no_addr);
877 lh->lh_quota_addr =
878 cpu_to_be64(GFS2_I(sdp->sd_qc_inode)->i_no_addr);
879
880 spin_lock(&sdp->sd_statfs_spin);
881 lh->lh_local_total = cpu_to_be64(l_sc->sc_total);
882 lh->lh_local_free = cpu_to_be64(l_sc->sc_free);
883 lh->lh_local_dinodes = cpu_to_be64(l_sc->sc_dinodes);
884 spin_unlock(&sdp->sd_statfs_spin);
885 }
886
887 BUILD_BUG_ON(offsetof(struct gfs2_log_header, lh_crc) != LH_V1_SIZE);
888
889 crc = crc32c(~0, (void *)lh + LH_V1_SIZE + 4,
890 sb->s_blocksize - LH_V1_SIZE - 4);
891 lh->lh_crc = cpu_to_be32(crc);
892
893 gfs2_log_write(sdp, jd, page, sb->s_blocksize, 0, dblock);
894 gfs2_log_submit_bio(&jd->jd_log_bio, REQ_OP_WRITE | op_flags);
895}
896
897/**
898 * log_write_header - Get and initialize a journal header buffer
899 * @sdp: The GFS2 superblock
900 * @flags: The log header flags, including log header origin
901 *
902 * Returns: the initialized log buffer descriptor
903 */
904
905static void log_write_header(struct gfs2_sbd *sdp, u32 flags)
906{
907 blk_opf_t op_flags = REQ_PREFLUSH | REQ_FUA | REQ_META | REQ_SYNC;
908 struct super_block *sb = sdp->sd_vfs;
909
910 gfs2_assert_withdraw(sdp, sb->s_writers.frozen != SB_FREEZE_COMPLETE);
911
912 if (test_bit(SDF_NOBARRIERS, &sdp->sd_flags)) {
913 gfs2_ordered_wait(sdp);
914 log_flush_wait(sdp);
915 op_flags = REQ_SYNC | REQ_META | REQ_PRIO;
916 }
917 sdp->sd_log_idle = (sdp->sd_log_flush_tail == sdp->sd_log_flush_head);
918 gfs2_write_log_header(sdp, sdp->sd_jdesc, sdp->sd_log_sequence++,
919 sdp->sd_log_flush_tail, sdp->sd_log_flush_head,
920 flags, op_flags);
921 gfs2_log_incr_head(sdp);
922 log_flush_wait(sdp);
923 log_pull_tail(sdp);
924 gfs2_log_update_head(sdp);
925}
926
927/**
928 * gfs2_ail_drain - drain the ail lists after a withdraw
929 * @sdp: Pointer to GFS2 superblock
930 */
931void gfs2_ail_drain(struct gfs2_sbd *sdp)
932{
933 struct gfs2_trans *tr;
934
935 spin_lock(&sdp->sd_ail_lock);
936 /*
937 * For transactions on the sd_ail1_list we need to drain both the
938 * ail1 and ail2 lists. That's because function gfs2_ail1_start_one
939 * (temporarily) moves items from its tr_ail1 list to tr_ail2 list
940 * before revokes are sent for that block. Items on the sd_ail2_list
941 * should have already gotten beyond that point, so no need.
942 */
943 while (!list_empty(&sdp->sd_ail1_list)) {
944 tr = list_first_entry(&sdp->sd_ail1_list, struct gfs2_trans,
945 tr_list);
946 gfs2_ail_empty_tr(sdp, tr, &tr->tr_ail1_list);
947 gfs2_ail_empty_tr(sdp, tr, &tr->tr_ail2_list);
948 list_del(&tr->tr_list);
949 gfs2_trans_free(sdp, tr);
950 }
951 while (!list_empty(&sdp->sd_ail2_list)) {
952 tr = list_first_entry(&sdp->sd_ail2_list, struct gfs2_trans,
953 tr_list);
954 gfs2_ail_empty_tr(sdp, tr, &tr->tr_ail2_list);
955 list_del(&tr->tr_list);
956 gfs2_trans_free(sdp, tr);
957 }
958 gfs2_drain_revokes(sdp);
959 spin_unlock(&sdp->sd_ail_lock);
960}
961
962/**
963 * empty_ail1_list - try to start IO and empty the ail1 list
964 * @sdp: Pointer to GFS2 superblock
965 */
966static void empty_ail1_list(struct gfs2_sbd *sdp)
967{
968 unsigned long start = jiffies;
969 bool empty = false;
970
971 while (!empty) {
972 if (time_after(jiffies, start + (HZ * 600))) {
973 fs_err(sdp, "Error: In %s for 10 minutes! t=%d\n",
974 __func__, current->journal_info ? 1 : 0);
975 dump_ail_list(sdp);
976 return;
977 }
978 gfs2_ail1_start(sdp);
979 gfs2_ail1_wait(sdp);
980 empty = gfs2_ail1_empty(sdp, 0);
981
982 if (gfs2_withdrawing_or_withdrawn(sdp))
983 break;
984 }
985
986 if (gfs2_withdrawing(sdp))
987 gfs2_withdraw(sdp);
988}
989
990/**
991 * trans_drain - drain the buf and databuf queue for a failed transaction
992 * @tr: the transaction to drain
993 *
994 * When this is called, we're taking an error exit for a log write that failed
995 * but since we bypassed the after_commit functions, we need to remove the
996 * items from the buf and databuf queue.
997 */
998static void trans_drain(struct gfs2_trans *tr)
999{
1000 struct gfs2_bufdata *bd;
1001 struct list_head *head;
1002
1003 if (!tr)
1004 return;
1005
1006 head = &tr->tr_buf;
1007 while (!list_empty(head)) {
1008 bd = list_first_entry(head, struct gfs2_bufdata, bd_list);
1009 list_del_init(&bd->bd_list);
1010 if (!list_empty(&bd->bd_ail_st_list))
1011 gfs2_remove_from_ail(bd);
1012 kmem_cache_free(gfs2_bufdata_cachep, bd);
1013 }
1014 head = &tr->tr_databuf;
1015 while (!list_empty(head)) {
1016 bd = list_first_entry(head, struct gfs2_bufdata, bd_list);
1017 list_del_init(&bd->bd_list);
1018 if (!list_empty(&bd->bd_ail_st_list))
1019 gfs2_remove_from_ail(bd);
1020 kmem_cache_free(gfs2_bufdata_cachep, bd);
1021 }
1022}
1023
1024/**
1025 * gfs2_log_flush - flush incore transaction(s)
1026 * @sdp: The filesystem
1027 * @gl: The glock structure to flush. If NULL, flush the whole incore log
1028 * @flags: The log header flags: GFS2_LOG_HEAD_FLUSH_* and debug flags
1029 *
1030 */
1031
1032void gfs2_log_flush(struct gfs2_sbd *sdp, struct gfs2_glock *gl, u32 flags)
1033{
1034 struct gfs2_trans *tr = NULL;
1035 unsigned int reserved_blocks = 0, used_blocks = 0;
1036 bool frozen = test_bit(SDF_FROZEN, &sdp->sd_flags);
1037 unsigned int first_log_head;
1038 unsigned int reserved_revokes = 0;
1039
1040 down_write(&sdp->sd_log_flush_lock);
1041 trace_gfs2_log_flush(sdp, 1, flags);
1042
1043repeat:
1044 /*
1045 * Do this check while holding the log_flush_lock to prevent new
1046 * buffers from being added to the ail via gfs2_pin()
1047 */
1048 if (gfs2_withdrawing_or_withdrawn(sdp) ||
1049 !test_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags))
1050 goto out;
1051
1052 /* Log might have been flushed while we waited for the flush lock */
1053 if (gl && !test_bit(GLF_LFLUSH, &gl->gl_flags))
1054 goto out;
1055
1056 first_log_head = sdp->sd_log_head;
1057 sdp->sd_log_flush_head = first_log_head;
1058
1059 tr = sdp->sd_log_tr;
1060 if (tr || sdp->sd_log_num_revoke) {
1061 if (reserved_blocks)
1062 gfs2_log_release(sdp, reserved_blocks);
1063 reserved_blocks = sdp->sd_log_blks_reserved;
1064 reserved_revokes = sdp->sd_log_num_revoke;
1065 if (tr) {
1066 sdp->sd_log_tr = NULL;
1067 tr->tr_first = first_log_head;
1068 if (unlikely(frozen)) {
1069 if (gfs2_assert_withdraw_delayed(sdp,
1070 !tr->tr_num_buf_new && !tr->tr_num_databuf_new))
1071 goto out_withdraw;
1072 }
1073 }
1074 } else if (!reserved_blocks) {
1075 unsigned int taboo_blocks = GFS2_LOG_FLUSH_MIN_BLOCKS;
1076
1077 reserved_blocks = GFS2_LOG_FLUSH_MIN_BLOCKS;
1078 if (current == sdp->sd_logd_process)
1079 taboo_blocks = 0;
1080
1081 if (!__gfs2_log_try_reserve(sdp, reserved_blocks, taboo_blocks)) {
1082 up_write(&sdp->sd_log_flush_lock);
1083 __gfs2_log_reserve(sdp, reserved_blocks, taboo_blocks);
1084 down_write(&sdp->sd_log_flush_lock);
1085 goto repeat;
1086 }
1087 BUG_ON(sdp->sd_log_num_revoke);
1088 }
1089
1090 if (flags & GFS2_LOG_HEAD_FLUSH_SHUTDOWN)
1091 clear_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags);
1092
1093 if (unlikely(frozen))
1094 if (gfs2_assert_withdraw_delayed(sdp, !reserved_revokes))
1095 goto out_withdraw;
1096
1097 gfs2_ordered_write(sdp);
1098 if (gfs2_withdrawing_or_withdrawn(sdp))
1099 goto out_withdraw;
1100 lops_before_commit(sdp, tr);
1101 if (gfs2_withdrawing_or_withdrawn(sdp))
1102 goto out_withdraw;
1103 if (sdp->sd_jdesc)
1104 gfs2_log_submit_bio(&sdp->sd_jdesc->jd_log_bio, REQ_OP_WRITE);
1105 if (gfs2_withdrawing_or_withdrawn(sdp))
1106 goto out_withdraw;
1107
1108 if (sdp->sd_log_head != sdp->sd_log_flush_head) {
1109 log_write_header(sdp, flags);
1110 } else if (sdp->sd_log_tail != sdp->sd_log_flush_tail && !sdp->sd_log_idle) {
1111 log_write_header(sdp, flags);
1112 }
1113 if (gfs2_withdrawing_or_withdrawn(sdp))
1114 goto out_withdraw;
1115 lops_after_commit(sdp, tr);
1116
1117 gfs2_log_lock(sdp);
1118 sdp->sd_log_blks_reserved = 0;
1119
1120 spin_lock(&sdp->sd_ail_lock);
1121 if (tr && !list_empty(&tr->tr_ail1_list)) {
1122 list_add(&tr->tr_list, &sdp->sd_ail1_list);
1123 tr = NULL;
1124 }
1125 spin_unlock(&sdp->sd_ail_lock);
1126 gfs2_log_unlock(sdp);
1127
1128 if (!(flags & GFS2_LOG_HEAD_FLUSH_NORMAL)) {
1129 if (!sdp->sd_log_idle) {
1130 empty_ail1_list(sdp);
1131 if (gfs2_withdrawing_or_withdrawn(sdp))
1132 goto out_withdraw;
1133 log_write_header(sdp, flags);
1134 }
1135 if (flags & (GFS2_LOG_HEAD_FLUSH_SHUTDOWN |
1136 GFS2_LOG_HEAD_FLUSH_FREEZE))
1137 gfs2_log_shutdown(sdp);
1138 }
1139
1140out_end:
1141 used_blocks = log_distance(sdp, sdp->sd_log_flush_head, first_log_head);
1142 reserved_revokes += atomic_read(&sdp->sd_log_revokes_available);
1143 atomic_set(&sdp->sd_log_revokes_available, sdp->sd_ldptrs);
1144 gfs2_assert_withdraw(sdp, reserved_revokes % sdp->sd_inptrs == sdp->sd_ldptrs);
1145 if (reserved_revokes > sdp->sd_ldptrs)
1146 reserved_blocks += (reserved_revokes - sdp->sd_ldptrs) / sdp->sd_inptrs;
1147out:
1148 if (used_blocks != reserved_blocks) {
1149 gfs2_assert_withdraw_delayed(sdp, used_blocks < reserved_blocks);
1150 gfs2_log_release(sdp, reserved_blocks - used_blocks);
1151 }
1152 up_write(&sdp->sd_log_flush_lock);
1153 gfs2_trans_free(sdp, tr);
1154 if (gfs2_withdrawing(sdp))
1155 gfs2_withdraw(sdp);
1156 trace_gfs2_log_flush(sdp, 0, flags);
1157 return;
1158
1159out_withdraw:
1160 trans_drain(tr);
1161 /**
1162 * If the tr_list is empty, we're withdrawing during a log
1163 * flush that targets a transaction, but the transaction was
1164 * never queued onto any of the ail lists. Here we add it to
1165 * ail1 just so that ail_drain() will find and free it.
1166 */
1167 spin_lock(&sdp->sd_ail_lock);
1168 if (tr && list_empty(&tr->tr_list))
1169 list_add(&tr->tr_list, &sdp->sd_ail1_list);
1170 spin_unlock(&sdp->sd_ail_lock);
1171 tr = NULL;
1172 goto out_end;
1173}
1174
1175/**
1176 * gfs2_merge_trans - Merge a new transaction into a cached transaction
1177 * @sdp: the filesystem
1178 * @new: New transaction to be merged
1179 */
1180
1181static void gfs2_merge_trans(struct gfs2_sbd *sdp, struct gfs2_trans *new)
1182{
1183 struct gfs2_trans *old = sdp->sd_log_tr;
1184
1185 WARN_ON_ONCE(!test_bit(TR_ATTACHED, &old->tr_flags));
1186
1187 old->tr_num_buf_new += new->tr_num_buf_new;
1188 old->tr_num_databuf_new += new->tr_num_databuf_new;
1189 old->tr_num_buf_rm += new->tr_num_buf_rm;
1190 old->tr_num_databuf_rm += new->tr_num_databuf_rm;
1191 old->tr_revokes += new->tr_revokes;
1192 old->tr_num_revoke += new->tr_num_revoke;
1193
1194 list_splice_tail_init(&new->tr_databuf, &old->tr_databuf);
1195 list_splice_tail_init(&new->tr_buf, &old->tr_buf);
1196
1197 spin_lock(&sdp->sd_ail_lock);
1198 list_splice_tail_init(&new->tr_ail1_list, &old->tr_ail1_list);
1199 list_splice_tail_init(&new->tr_ail2_list, &old->tr_ail2_list);
1200 spin_unlock(&sdp->sd_ail_lock);
1201}
1202
1203static void log_refund(struct gfs2_sbd *sdp, struct gfs2_trans *tr)
1204{
1205 unsigned int reserved;
1206 unsigned int unused;
1207 unsigned int maxres;
1208
1209 gfs2_log_lock(sdp);
1210
1211 if (sdp->sd_log_tr) {
1212 gfs2_merge_trans(sdp, tr);
1213 } else if (tr->tr_num_buf_new || tr->tr_num_databuf_new) {
1214 gfs2_assert_withdraw(sdp, !test_bit(TR_ONSTACK, &tr->tr_flags));
1215 sdp->sd_log_tr = tr;
1216 set_bit(TR_ATTACHED, &tr->tr_flags);
1217 }
1218
1219 reserved = calc_reserved(sdp);
1220 maxres = sdp->sd_log_blks_reserved + tr->tr_reserved;
1221 gfs2_assert_withdraw(sdp, maxres >= reserved);
1222 unused = maxres - reserved;
1223 if (unused)
1224 gfs2_log_release(sdp, unused);
1225 sdp->sd_log_blks_reserved = reserved;
1226
1227 gfs2_log_unlock(sdp);
1228}
1229
1230static inline int gfs2_jrnl_flush_reqd(struct gfs2_sbd *sdp)
1231{
1232 return atomic_read(&sdp->sd_log_pinned) +
1233 atomic_read(&sdp->sd_log_blks_needed) >=
1234 atomic_read(&sdp->sd_log_thresh1);
1235}
1236
1237static inline int gfs2_ail_flush_reqd(struct gfs2_sbd *sdp)
1238{
1239 return sdp->sd_jdesc->jd_blocks -
1240 atomic_read(&sdp->sd_log_blks_free) +
1241 atomic_read(&sdp->sd_log_blks_needed) >=
1242 atomic_read(&sdp->sd_log_thresh2);
1243}
1244
1245/**
1246 * gfs2_log_commit - Commit a transaction to the log
1247 * @sdp: the filesystem
1248 * @tr: the transaction
1249 *
1250 * We wake up gfs2_logd if the number of pinned blocks exceed thresh1
1251 * or the total number of used blocks (pinned blocks plus AIL blocks)
1252 * is greater than thresh2.
1253 *
1254 * At mount time thresh1 is 2/5ths of journal size, thresh2 is 4/5ths of
1255 * journal size.
1256 *
1257 * Returns: errno
1258 */
1259
1260void gfs2_log_commit(struct gfs2_sbd *sdp, struct gfs2_trans *tr)
1261{
1262 log_refund(sdp, tr);
1263
1264 if (gfs2_ail_flush_reqd(sdp) || gfs2_jrnl_flush_reqd(sdp))
1265 wake_up(&sdp->sd_logd_waitq);
1266}
1267
1268/**
1269 * gfs2_log_shutdown - write a shutdown header into a journal
1270 * @sdp: the filesystem
1271 *
1272 */
1273
1274static void gfs2_log_shutdown(struct gfs2_sbd *sdp)
1275{
1276 gfs2_assert_withdraw(sdp, !sdp->sd_log_blks_reserved);
1277 gfs2_assert_withdraw(sdp, !sdp->sd_log_num_revoke);
1278 gfs2_assert_withdraw(sdp, list_empty(&sdp->sd_ail1_list));
1279
1280 log_write_header(sdp, GFS2_LOG_HEAD_UNMOUNT | GFS2_LFC_SHUTDOWN);
1281 log_pull_tail(sdp);
1282
1283 gfs2_assert_warn(sdp, sdp->sd_log_head == sdp->sd_log_tail);
1284 gfs2_assert_warn(sdp, list_empty(&sdp->sd_ail2_list));
1285}
1286
1287/**
1288 * gfs2_logd - Update log tail as Active Items get flushed to in-place blocks
1289 * @data: Pointer to GFS2 superblock
1290 *
1291 * Also, periodically check to make sure that we're using the most recent
1292 * journal index.
1293 */
1294
1295int gfs2_logd(void *data)
1296{
1297 struct gfs2_sbd *sdp = data;
1298 unsigned long t = 1;
1299
1300 set_freezable();
1301 while (!kthread_should_stop()) {
1302 if (gfs2_withdrawing_or_withdrawn(sdp))
1303 break;
1304
1305 /* Check for errors writing to the journal */
1306 if (sdp->sd_log_error) {
1307 gfs2_lm(sdp,
1308 "GFS2: fsid=%s: error %d: "
1309 "withdrawing the file system to "
1310 "prevent further damage.\n",
1311 sdp->sd_fsname, sdp->sd_log_error);
1312 gfs2_withdraw(sdp);
1313 break;
1314 }
1315
1316 if (gfs2_jrnl_flush_reqd(sdp) || t == 0) {
1317 gfs2_ail1_empty(sdp, 0);
1318 gfs2_log_flush(sdp, NULL, GFS2_LOG_HEAD_FLUSH_NORMAL |
1319 GFS2_LFC_LOGD_JFLUSH_REQD);
1320 }
1321
1322 if (test_bit(SDF_FORCE_AIL_FLUSH, &sdp->sd_flags) ||
1323 gfs2_ail_flush_reqd(sdp)) {
1324 clear_bit(SDF_FORCE_AIL_FLUSH, &sdp->sd_flags);
1325 gfs2_ail1_start(sdp);
1326 gfs2_ail1_wait(sdp);
1327 gfs2_ail1_empty(sdp, 0);
1328 gfs2_log_flush(sdp, NULL, GFS2_LOG_HEAD_FLUSH_NORMAL |
1329 GFS2_LFC_LOGD_AIL_FLUSH_REQD);
1330 }
1331
1332 t = gfs2_tune_get(sdp, gt_logd_secs) * HZ;
1333
1334 t = wait_event_freezable_timeout(sdp->sd_logd_waitq,
1335 test_bit(SDF_FORCE_AIL_FLUSH, &sdp->sd_flags) ||
1336 gfs2_ail_flush_reqd(sdp) ||
1337 gfs2_jrnl_flush_reqd(sdp) ||
1338 sdp->sd_log_error ||
1339 gfs2_withdrawing_or_withdrawn(sdp) ||
1340 kthread_should_stop(),
1341 t);
1342 }
1343
1344 if (gfs2_withdrawing(sdp))
1345 gfs2_withdraw(sdp);
1346
1347 return 0;
1348}
1349