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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/writeback.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
34#define PULL 1
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_ail = 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_ail *ai)
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, &ai->ai_ail1_list, bd_ail_st_list) {
104 bh = bd->bd_bh;
105
106 gfs2_assert(sdp, bd->bd_ail == ai);
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, &ai->ai_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, &ai->ai_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_ail *ai;
149
150 trace_gfs2_ail_flush(sdp, wbc, 1);
151 spin_lock(&sdp->sd_ail_lock);
152restart:
153 list_for_each_entry_reverse(ai, head, ai_list) {
154 if (wbc->nr_to_write <= 0)
155 break;
156 if (gfs2_ail1_start_one(sdp, wbc, ai))
157 goto restart;
158 }
159 spin_unlock(&sdp->sd_ail_lock);
160 trace_gfs2_ail_flush(sdp, wbc, 0);
161}
162
163/**
164 * gfs2_ail1_start - start writeback of all ail1 entries
165 * @sdp: The superblock
166 */
167
168static void gfs2_ail1_start(struct gfs2_sbd *sdp)
169{
170 struct writeback_control wbc = {
171 .sync_mode = WB_SYNC_NONE,
172 .nr_to_write = LONG_MAX,
173 .range_start = 0,
174 .range_end = LLONG_MAX,
175 };
176
177 return gfs2_ail1_flush(sdp, &wbc);
178}
179
180/**
181 * gfs2_ail1_empty_one - Check whether or not a trans in the AIL has been synced
182 * @sdp: the filesystem
183 * @ai: the AIL entry
184 *
185 */
186
187static void gfs2_ail1_empty_one(struct gfs2_sbd *sdp, struct gfs2_ail *ai)
188{
189 struct gfs2_bufdata *bd, *s;
190 struct buffer_head *bh;
191
192 list_for_each_entry_safe_reverse(bd, s, &ai->ai_ail1_list,
193 bd_ail_st_list) {
194 bh = bd->bd_bh;
195 gfs2_assert(sdp, bd->bd_ail == ai);
196 if (buffer_busy(bh))
197 continue;
198 if (!buffer_uptodate(bh))
199 gfs2_io_error_bh(sdp, bh);
200 list_move(&bd->bd_ail_st_list, &ai->ai_ail2_list);
201 }
202
203}
204
205/**
206 * gfs2_ail1_empty - Try to empty the ail1 lists
207 * @sdp: The superblock
208 *
209 * Tries to empty the ail1 lists, starting with the oldest first
210 */
211
212static int gfs2_ail1_empty(struct gfs2_sbd *sdp)
213{
214 struct gfs2_ail *ai, *s;
215 int ret;
216
217 spin_lock(&sdp->sd_ail_lock);
218 list_for_each_entry_safe_reverse(ai, s, &sdp->sd_ail1_list, ai_list) {
219 gfs2_ail1_empty_one(sdp, ai);
220 if (list_empty(&ai->ai_ail1_list))
221 list_move(&ai->ai_list, &sdp->sd_ail2_list);
222 else
223 break;
224 }
225 ret = list_empty(&sdp->sd_ail1_list);
226 spin_unlock(&sdp->sd_ail_lock);
227
228 return ret;
229}
230
231static void gfs2_ail1_wait(struct gfs2_sbd *sdp)
232{
233 struct gfs2_ail *ai;
234 struct gfs2_bufdata *bd;
235 struct buffer_head *bh;
236
237 spin_lock(&sdp->sd_ail_lock);
238 list_for_each_entry_reverse(ai, &sdp->sd_ail1_list, ai_list) {
239 list_for_each_entry(bd, &ai->ai_ail1_list, bd_ail_st_list) {
240 bh = bd->bd_bh;
241 if (!buffer_locked(bh))
242 continue;
243 get_bh(bh);
244 spin_unlock(&sdp->sd_ail_lock);
245 wait_on_buffer(bh);
246 brelse(bh);
247 return;
248 }
249 }
250 spin_unlock(&sdp->sd_ail_lock);
251}
252
253/**
254 * gfs2_ail2_empty_one - Check whether or not a trans in the AIL has been synced
255 * @sdp: the filesystem
256 * @ai: the AIL entry
257 *
258 */
259
260static void gfs2_ail2_empty_one(struct gfs2_sbd *sdp, struct gfs2_ail *ai)
261{
262 struct list_head *head = &ai->ai_ail2_list;
263 struct gfs2_bufdata *bd;
264
265 while (!list_empty(head)) {
266 bd = list_entry(head->prev, struct gfs2_bufdata,
267 bd_ail_st_list);
268 gfs2_assert(sdp, bd->bd_ail == ai);
269 gfs2_remove_from_ail(bd);
270 }
271}
272
273static void ail2_empty(struct gfs2_sbd *sdp, unsigned int new_tail)
274{
275 struct gfs2_ail *ai, *safe;
276 unsigned int old_tail = sdp->sd_log_tail;
277 int wrap = (new_tail < old_tail);
278 int a, b, rm;
279
280 spin_lock(&sdp->sd_ail_lock);
281
282 list_for_each_entry_safe(ai, safe, &sdp->sd_ail2_list, ai_list) {
283 a = (old_tail <= ai->ai_first);
284 b = (ai->ai_first < new_tail);
285 rm = (wrap) ? (a || b) : (a && b);
286 if (!rm)
287 continue;
288
289 gfs2_ail2_empty_one(sdp, ai);
290 list_del(&ai->ai_list);
291 gfs2_assert_warn(sdp, list_empty(&ai->ai_ail1_list));
292 gfs2_assert_warn(sdp, list_empty(&ai->ai_ail2_list));
293 kfree(ai);
294 }
295
296 spin_unlock(&sdp->sd_ail_lock);
297}
298
299/**
300 * gfs2_log_reserve - Make a log reservation
301 * @sdp: The GFS2 superblock
302 * @blks: The number of blocks to reserve
303 *
304 * Note that we never give out the last few blocks of the journal. Thats
305 * due to the fact that there is a small number of header blocks
306 * associated with each log flush. The exact number can't be known until
307 * flush time, so we ensure that we have just enough free blocks at all
308 * times to avoid running out during a log flush.
309 *
310 * We no longer flush the log here, instead we wake up logd to do that
311 * for us. To avoid the thundering herd and to ensure that we deal fairly
312 * with queued waiters, we use an exclusive wait. This means that when we
313 * get woken with enough journal space to get our reservation, we need to
314 * wake the next waiter on the list.
315 *
316 * Returns: errno
317 */
318
319int gfs2_log_reserve(struct gfs2_sbd *sdp, unsigned int blks)
320{
321 unsigned reserved_blks = 6 * (4096 / sdp->sd_vfs->s_blocksize);
322 unsigned wanted = blks + reserved_blks;
323 DEFINE_WAIT(wait);
324 int did_wait = 0;
325 unsigned int free_blocks;
326
327 if (gfs2_assert_warn(sdp, blks) ||
328 gfs2_assert_warn(sdp, blks <= sdp->sd_jdesc->jd_blocks))
329 return -EINVAL;
330retry:
331 free_blocks = atomic_read(&sdp->sd_log_blks_free);
332 if (unlikely(free_blocks <= wanted)) {
333 do {
334 prepare_to_wait_exclusive(&sdp->sd_log_waitq, &wait,
335 TASK_UNINTERRUPTIBLE);
336 wake_up(&sdp->sd_logd_waitq);
337 did_wait = 1;
338 if (atomic_read(&sdp->sd_log_blks_free) <= wanted)
339 io_schedule();
340 free_blocks = atomic_read(&sdp->sd_log_blks_free);
341 } while(free_blocks <= wanted);
342 finish_wait(&sdp->sd_log_waitq, &wait);
343 }
344 if (atomic_cmpxchg(&sdp->sd_log_blks_free, free_blocks,
345 free_blocks - blks) != free_blocks)
346 goto retry;
347 trace_gfs2_log_blocks(sdp, -blks);
348
349 /*
350 * If we waited, then so might others, wake them up _after_ we get
351 * our share of the log.
352 */
353 if (unlikely(did_wait))
354 wake_up(&sdp->sd_log_waitq);
355
356 down_read(&sdp->sd_log_flush_lock);
357
358 return 0;
359}
360
361static u64 log_bmap(struct gfs2_sbd *sdp, unsigned int lbn)
362{
363 struct gfs2_journal_extent *je;
364
365 list_for_each_entry(je, &sdp->sd_jdesc->extent_list, extent_list) {
366 if (lbn >= je->lblock && lbn < je->lblock + je->blocks)
367 return je->dblock + lbn - je->lblock;
368 }
369
370 return -1;
371}
372
373/**
374 * log_distance - Compute distance between two journal blocks
375 * @sdp: The GFS2 superblock
376 * @newer: The most recent journal block of the pair
377 * @older: The older journal block of the pair
378 *
379 * Compute the distance (in the journal direction) between two
380 * blocks in the journal
381 *
382 * Returns: the distance in blocks
383 */
384
385static inline unsigned int log_distance(struct gfs2_sbd *sdp, unsigned int newer,
386 unsigned int older)
387{
388 int dist;
389
390 dist = newer - older;
391 if (dist < 0)
392 dist += sdp->sd_jdesc->jd_blocks;
393
394 return dist;
395}
396
397/**
398 * calc_reserved - Calculate the number of blocks to reserve when
399 * refunding a transaction's unused buffers.
400 * @sdp: The GFS2 superblock
401 *
402 * This is complex. We need to reserve room for all our currently used
403 * metadata buffers (e.g. normal file I/O rewriting file time stamps) and
404 * all our journaled data buffers for journaled files (e.g. files in the
405 * meta_fs like rindex, or files for which chattr +j was done.)
406 * If we don't reserve enough space, gfs2_log_refund and gfs2_log_flush
407 * will count it as free space (sd_log_blks_free) and corruption will follow.
408 *
409 * We can have metadata bufs and jdata bufs in the same journal. So each
410 * type gets its own log header, for which we need to reserve a block.
411 * In fact, each type has the potential for needing more than one header
412 * in cases where we have more buffers than will fit on a journal page.
413 * Metadata journal entries take up half the space of journaled buffer entries.
414 * Thus, metadata entries have buf_limit (502) and journaled buffers have
415 * databuf_limit (251) before they cause a wrap around.
416 *
417 * Also, we need to reserve blocks for revoke journal entries and one for an
418 * overall header for the lot.
419 *
420 * Returns: the number of blocks reserved
421 */
422static unsigned int calc_reserved(struct gfs2_sbd *sdp)
423{
424 unsigned int reserved = 0;
425 unsigned int mbuf_limit, metabufhdrs_needed;
426 unsigned int dbuf_limit, databufhdrs_needed;
427 unsigned int revokes = 0;
428
429 mbuf_limit = buf_limit(sdp);
430 metabufhdrs_needed = (sdp->sd_log_commited_buf +
431 (mbuf_limit - 1)) / mbuf_limit;
432 dbuf_limit = databuf_limit(sdp);
433 databufhdrs_needed = (sdp->sd_log_commited_databuf +
434 (dbuf_limit - 1)) / dbuf_limit;
435
436 if (sdp->sd_log_commited_revoke > 0)
437 revokes = gfs2_struct2blk(sdp, sdp->sd_log_commited_revoke,
438 sizeof(u64));
439
440 reserved = sdp->sd_log_commited_buf + metabufhdrs_needed +
441 sdp->sd_log_commited_databuf + databufhdrs_needed +
442 revokes;
443 /* One for the overall header */
444 if (reserved)
445 reserved++;
446 return reserved;
447}
448
449static unsigned int current_tail(struct gfs2_sbd *sdp)
450{
451 struct gfs2_ail *ai;
452 unsigned int tail;
453
454 spin_lock(&sdp->sd_ail_lock);
455
456 if (list_empty(&sdp->sd_ail1_list)) {
457 tail = sdp->sd_log_head;
458 } else {
459 ai = list_entry(sdp->sd_ail1_list.prev, struct gfs2_ail, ai_list);
460 tail = ai->ai_first;
461 }
462
463 spin_unlock(&sdp->sd_ail_lock);
464
465 return tail;
466}
467
468void gfs2_log_incr_head(struct gfs2_sbd *sdp)
469{
470 if (sdp->sd_log_flush_head == sdp->sd_log_tail)
471 BUG_ON(sdp->sd_log_flush_head != sdp->sd_log_head);
472
473 if (++sdp->sd_log_flush_head == sdp->sd_jdesc->jd_blocks) {
474 sdp->sd_log_flush_head = 0;
475 sdp->sd_log_flush_wrapped = 1;
476 }
477}
478
479/**
480 * gfs2_log_write_endio - End of I/O for a log buffer
481 * @bh: The buffer head
482 * @uptodate: I/O Status
483 *
484 */
485
486static void gfs2_log_write_endio(struct buffer_head *bh, int uptodate)
487{
488 struct gfs2_sbd *sdp = bh->b_private;
489 bh->b_private = NULL;
490
491 end_buffer_write_sync(bh, uptodate);
492 if (atomic_dec_and_test(&sdp->sd_log_in_flight))
493 wake_up(&sdp->sd_log_flush_wait);
494}
495
496/**
497 * gfs2_log_get_buf - Get and initialize a buffer to use for log control data
498 * @sdp: The GFS2 superblock
499 *
500 * Returns: the buffer_head
501 */
502
503struct buffer_head *gfs2_log_get_buf(struct gfs2_sbd *sdp)
504{
505 u64 blkno = log_bmap(sdp, sdp->sd_log_flush_head);
506 struct buffer_head *bh;
507
508 bh = sb_getblk(sdp->sd_vfs, blkno);
509 lock_buffer(bh);
510 memset(bh->b_data, 0, bh->b_size);
511 set_buffer_uptodate(bh);
512 clear_buffer_dirty(bh);
513 gfs2_log_incr_head(sdp);
514 atomic_inc(&sdp->sd_log_in_flight);
515 bh->b_private = sdp;
516 bh->b_end_io = gfs2_log_write_endio;
517
518 return bh;
519}
520
521/**
522 * gfs2_fake_write_endio -
523 * @bh: The buffer head
524 * @uptodate: The I/O Status
525 *
526 */
527
528static void gfs2_fake_write_endio(struct buffer_head *bh, int uptodate)
529{
530 struct buffer_head *real_bh = bh->b_private;
531 struct gfs2_bufdata *bd = real_bh->b_private;
532 struct gfs2_sbd *sdp = bd->bd_gl->gl_sbd;
533
534 end_buffer_write_sync(bh, uptodate);
535 free_buffer_head(bh);
536 unlock_buffer(real_bh);
537 brelse(real_bh);
538 if (atomic_dec_and_test(&sdp->sd_log_in_flight))
539 wake_up(&sdp->sd_log_flush_wait);
540}
541
542/**
543 * gfs2_log_fake_buf - Build a fake buffer head to write metadata buffer to log
544 * @sdp: the filesystem
545 * @data: the data the buffer_head should point to
546 *
547 * Returns: the log buffer descriptor
548 */
549
550struct buffer_head *gfs2_log_fake_buf(struct gfs2_sbd *sdp,
551 struct buffer_head *real)
552{
553 u64 blkno = log_bmap(sdp, sdp->sd_log_flush_head);
554 struct buffer_head *bh;
555
556 bh = alloc_buffer_head(GFP_NOFS | __GFP_NOFAIL);
557 atomic_set(&bh->b_count, 1);
558 bh->b_state = (1 << BH_Mapped) | (1 << BH_Uptodate) | (1 << BH_Lock);
559 set_bh_page(bh, real->b_page, bh_offset(real));
560 bh->b_blocknr = blkno;
561 bh->b_size = sdp->sd_sb.sb_bsize;
562 bh->b_bdev = sdp->sd_vfs->s_bdev;
563 bh->b_private = real;
564 bh->b_end_io = gfs2_fake_write_endio;
565
566 gfs2_log_incr_head(sdp);
567 atomic_inc(&sdp->sd_log_in_flight);
568
569 return bh;
570}
571
572static void log_pull_tail(struct gfs2_sbd *sdp, unsigned int new_tail)
573{
574 unsigned int dist = log_distance(sdp, new_tail, sdp->sd_log_tail);
575
576 ail2_empty(sdp, new_tail);
577
578 atomic_add(dist, &sdp->sd_log_blks_free);
579 trace_gfs2_log_blocks(sdp, dist);
580 gfs2_assert_withdraw(sdp, atomic_read(&sdp->sd_log_blks_free) <=
581 sdp->sd_jdesc->jd_blocks);
582
583 sdp->sd_log_tail = new_tail;
584}
585
586/**
587 * log_write_header - Get and initialize a journal header buffer
588 * @sdp: The GFS2 superblock
589 *
590 * Returns: the initialized log buffer descriptor
591 */
592
593static void log_write_header(struct gfs2_sbd *sdp, u32 flags, int pull)
594{
595 u64 blkno = log_bmap(sdp, sdp->sd_log_flush_head);
596 struct buffer_head *bh;
597 struct gfs2_log_header *lh;
598 unsigned int tail;
599 u32 hash;
600
601 bh = sb_getblk(sdp->sd_vfs, blkno);
602 lock_buffer(bh);
603 memset(bh->b_data, 0, bh->b_size);
604 set_buffer_uptodate(bh);
605 clear_buffer_dirty(bh);
606
607 gfs2_ail1_empty(sdp);
608 tail = current_tail(sdp);
609
610 lh = (struct gfs2_log_header *)bh->b_data;
611 memset(lh, 0, sizeof(struct gfs2_log_header));
612 lh->lh_header.mh_magic = cpu_to_be32(GFS2_MAGIC);
613 lh->lh_header.mh_type = cpu_to_be32(GFS2_METATYPE_LH);
614 lh->lh_header.__pad0 = cpu_to_be64(0);
615 lh->lh_header.mh_format = cpu_to_be32(GFS2_FORMAT_LH);
616 lh->lh_header.mh_jid = cpu_to_be32(sdp->sd_jdesc->jd_jid);
617 lh->lh_sequence = cpu_to_be64(sdp->sd_log_sequence++);
618 lh->lh_flags = cpu_to_be32(flags);
619 lh->lh_tail = cpu_to_be32(tail);
620 lh->lh_blkno = cpu_to_be32(sdp->sd_log_flush_head);
621 hash = gfs2_disk_hash(bh->b_data, sizeof(struct gfs2_log_header));
622 lh->lh_hash = cpu_to_be32(hash);
623
624 bh->b_end_io = end_buffer_write_sync;
625 get_bh(bh);
626 if (test_bit(SDF_NOBARRIERS, &sdp->sd_flags))
627 submit_bh(WRITE_SYNC | REQ_META | REQ_PRIO, bh);
628 else
629 submit_bh(WRITE_FLUSH_FUA | REQ_META | REQ_PRIO, bh);
630 wait_on_buffer(bh);
631
632 if (!buffer_uptodate(bh))
633 gfs2_io_error_bh(sdp, bh);
634 brelse(bh);
635
636 if (sdp->sd_log_tail != tail)
637 log_pull_tail(sdp, tail);
638 else
639 gfs2_assert_withdraw(sdp, !pull);
640
641 sdp->sd_log_idle = (tail == sdp->sd_log_flush_head);
642 gfs2_log_incr_head(sdp);
643}
644
645static void log_flush_commit(struct gfs2_sbd *sdp)
646{
647 DEFINE_WAIT(wait);
648
649 if (atomic_read(&sdp->sd_log_in_flight)) {
650 do {
651 prepare_to_wait(&sdp->sd_log_flush_wait, &wait,
652 TASK_UNINTERRUPTIBLE);
653 if (atomic_read(&sdp->sd_log_in_flight))
654 io_schedule();
655 } while(atomic_read(&sdp->sd_log_in_flight));
656 finish_wait(&sdp->sd_log_flush_wait, &wait);
657 }
658
659 log_write_header(sdp, 0, 0);
660}
661
662static void gfs2_ordered_write(struct gfs2_sbd *sdp)
663{
664 struct gfs2_bufdata *bd;
665 struct buffer_head *bh;
666 LIST_HEAD(written);
667
668 gfs2_log_lock(sdp);
669 while (!list_empty(&sdp->sd_log_le_ordered)) {
670 bd = list_entry(sdp->sd_log_le_ordered.next, struct gfs2_bufdata, bd_le.le_list);
671 list_move(&bd->bd_le.le_list, &written);
672 bh = bd->bd_bh;
673 if (!buffer_dirty(bh))
674 continue;
675 get_bh(bh);
676 gfs2_log_unlock(sdp);
677 lock_buffer(bh);
678 if (buffer_mapped(bh) && test_clear_buffer_dirty(bh)) {
679 bh->b_end_io = end_buffer_write_sync;
680 submit_bh(WRITE_SYNC, bh);
681 } else {
682 unlock_buffer(bh);
683 brelse(bh);
684 }
685 gfs2_log_lock(sdp);
686 }
687 list_splice(&written, &sdp->sd_log_le_ordered);
688 gfs2_log_unlock(sdp);
689}
690
691static void gfs2_ordered_wait(struct gfs2_sbd *sdp)
692{
693 struct gfs2_bufdata *bd;
694 struct buffer_head *bh;
695
696 gfs2_log_lock(sdp);
697 while (!list_empty(&sdp->sd_log_le_ordered)) {
698 bd = list_entry(sdp->sd_log_le_ordered.prev, struct gfs2_bufdata, bd_le.le_list);
699 bh = bd->bd_bh;
700 if (buffer_locked(bh)) {
701 get_bh(bh);
702 gfs2_log_unlock(sdp);
703 wait_on_buffer(bh);
704 brelse(bh);
705 gfs2_log_lock(sdp);
706 continue;
707 }
708 list_del_init(&bd->bd_le.le_list);
709 }
710 gfs2_log_unlock(sdp);
711}
712
713/**
714 * gfs2_log_flush - flush incore transaction(s)
715 * @sdp: the filesystem
716 * @gl: The glock structure to flush. If NULL, flush the whole incore log
717 *
718 */
719
720void gfs2_log_flush(struct gfs2_sbd *sdp, struct gfs2_glock *gl)
721{
722 struct gfs2_ail *ai;
723
724 down_write(&sdp->sd_log_flush_lock);
725
726 /* Log might have been flushed while we waited for the flush lock */
727 if (gl && !test_bit(GLF_LFLUSH, &gl->gl_flags)) {
728 up_write(&sdp->sd_log_flush_lock);
729 return;
730 }
731 trace_gfs2_log_flush(sdp, 1);
732
733 ai = kzalloc(sizeof(struct gfs2_ail), GFP_NOFS | __GFP_NOFAIL);
734 INIT_LIST_HEAD(&ai->ai_ail1_list);
735 INIT_LIST_HEAD(&ai->ai_ail2_list);
736
737 if (sdp->sd_log_num_buf != sdp->sd_log_commited_buf) {
738 printk(KERN_INFO "GFS2: log buf %u %u\n", sdp->sd_log_num_buf,
739 sdp->sd_log_commited_buf);
740 gfs2_assert_withdraw(sdp, 0);
741 }
742 if (sdp->sd_log_num_databuf != sdp->sd_log_commited_databuf) {
743 printk(KERN_INFO "GFS2: log databuf %u %u\n",
744 sdp->sd_log_num_databuf, sdp->sd_log_commited_databuf);
745 gfs2_assert_withdraw(sdp, 0);
746 }
747 gfs2_assert_withdraw(sdp,
748 sdp->sd_log_num_revoke == sdp->sd_log_commited_revoke);
749
750 sdp->sd_log_flush_head = sdp->sd_log_head;
751 sdp->sd_log_flush_wrapped = 0;
752 ai->ai_first = sdp->sd_log_flush_head;
753
754 gfs2_ordered_write(sdp);
755 lops_before_commit(sdp);
756 gfs2_ordered_wait(sdp);
757
758 if (sdp->sd_log_head != sdp->sd_log_flush_head)
759 log_flush_commit(sdp);
760 else if (sdp->sd_log_tail != current_tail(sdp) && !sdp->sd_log_idle){
761 gfs2_log_lock(sdp);
762 atomic_dec(&sdp->sd_log_blks_free); /* Adjust for unreserved buffer */
763 trace_gfs2_log_blocks(sdp, -1);
764 gfs2_log_unlock(sdp);
765 log_write_header(sdp, 0, PULL);
766 }
767 lops_after_commit(sdp, ai);
768
769 gfs2_log_lock(sdp);
770 sdp->sd_log_head = sdp->sd_log_flush_head;
771 sdp->sd_log_blks_reserved = 0;
772 sdp->sd_log_commited_buf = 0;
773 sdp->sd_log_commited_databuf = 0;
774 sdp->sd_log_commited_revoke = 0;
775
776 spin_lock(&sdp->sd_ail_lock);
777 if (!list_empty(&ai->ai_ail1_list)) {
778 list_add(&ai->ai_list, &sdp->sd_ail1_list);
779 ai = NULL;
780 }
781 spin_unlock(&sdp->sd_ail_lock);
782 gfs2_log_unlock(sdp);
783 trace_gfs2_log_flush(sdp, 0);
784 up_write(&sdp->sd_log_flush_lock);
785
786 kfree(ai);
787}
788
789static void log_refund(struct gfs2_sbd *sdp, struct gfs2_trans *tr)
790{
791 unsigned int reserved;
792 unsigned int unused;
793
794 gfs2_log_lock(sdp);
795
796 sdp->sd_log_commited_buf += tr->tr_num_buf_new - tr->tr_num_buf_rm;
797 sdp->sd_log_commited_databuf += tr->tr_num_databuf_new -
798 tr->tr_num_databuf_rm;
799 gfs2_assert_withdraw(sdp, (((int)sdp->sd_log_commited_buf) >= 0) ||
800 (((int)sdp->sd_log_commited_databuf) >= 0));
801 sdp->sd_log_commited_revoke += tr->tr_num_revoke - tr->tr_num_revoke_rm;
802 reserved = calc_reserved(sdp);
803 gfs2_assert_withdraw(sdp, sdp->sd_log_blks_reserved + tr->tr_reserved >= reserved);
804 unused = sdp->sd_log_blks_reserved - reserved + tr->tr_reserved;
805 atomic_add(unused, &sdp->sd_log_blks_free);
806 trace_gfs2_log_blocks(sdp, unused);
807 gfs2_assert_withdraw(sdp, atomic_read(&sdp->sd_log_blks_free) <=
808 sdp->sd_jdesc->jd_blocks);
809 sdp->sd_log_blks_reserved = reserved;
810
811 gfs2_log_unlock(sdp);
812}
813
814static void buf_lo_incore_commit(struct gfs2_sbd *sdp, struct gfs2_trans *tr)
815{
816 struct list_head *head = &tr->tr_list_buf;
817 struct gfs2_bufdata *bd;
818
819 gfs2_log_lock(sdp);
820 while (!list_empty(head)) {
821 bd = list_entry(head->next, struct gfs2_bufdata, bd_list_tr);
822 list_del_init(&bd->bd_list_tr);
823 tr->tr_num_buf--;
824 }
825 gfs2_log_unlock(sdp);
826 gfs2_assert_warn(sdp, !tr->tr_num_buf);
827}
828
829/**
830 * gfs2_log_commit - Commit a transaction to the log
831 * @sdp: the filesystem
832 * @tr: the transaction
833 *
834 * We wake up gfs2_logd if the number of pinned blocks exceed thresh1
835 * or the total number of used blocks (pinned blocks plus AIL blocks)
836 * is greater than thresh2.
837 *
838 * At mount time thresh1 is 1/3rd of journal size, thresh2 is 2/3rd of
839 * journal size.
840 *
841 * Returns: errno
842 */
843
844void gfs2_log_commit(struct gfs2_sbd *sdp, struct gfs2_trans *tr)
845{
846 log_refund(sdp, tr);
847 buf_lo_incore_commit(sdp, tr);
848
849 up_read(&sdp->sd_log_flush_lock);
850
851 if (atomic_read(&sdp->sd_log_pinned) > atomic_read(&sdp->sd_log_thresh1) ||
852 ((sdp->sd_jdesc->jd_blocks - atomic_read(&sdp->sd_log_blks_free)) >
853 atomic_read(&sdp->sd_log_thresh2)))
854 wake_up(&sdp->sd_logd_waitq);
855}
856
857/**
858 * gfs2_log_shutdown - write a shutdown header into a journal
859 * @sdp: the filesystem
860 *
861 */
862
863void gfs2_log_shutdown(struct gfs2_sbd *sdp)
864{
865 down_write(&sdp->sd_log_flush_lock);
866
867 gfs2_assert_withdraw(sdp, !sdp->sd_log_blks_reserved);
868 gfs2_assert_withdraw(sdp, !sdp->sd_log_num_buf);
869 gfs2_assert_withdraw(sdp, !sdp->sd_log_num_revoke);
870 gfs2_assert_withdraw(sdp, !sdp->sd_log_num_rg);
871 gfs2_assert_withdraw(sdp, !sdp->sd_log_num_databuf);
872 gfs2_assert_withdraw(sdp, list_empty(&sdp->sd_ail1_list));
873
874 sdp->sd_log_flush_head = sdp->sd_log_head;
875 sdp->sd_log_flush_wrapped = 0;
876
877 log_write_header(sdp, GFS2_LOG_HEAD_UNMOUNT,
878 (sdp->sd_log_tail == current_tail(sdp)) ? 0 : PULL);
879
880 gfs2_assert_warn(sdp, atomic_read(&sdp->sd_log_blks_free) == sdp->sd_jdesc->jd_blocks);
881 gfs2_assert_warn(sdp, sdp->sd_log_head == sdp->sd_log_tail);
882 gfs2_assert_warn(sdp, list_empty(&sdp->sd_ail2_list));
883
884 sdp->sd_log_head = sdp->sd_log_flush_head;
885 sdp->sd_log_tail = sdp->sd_log_head;
886
887 up_write(&sdp->sd_log_flush_lock);
888}
889
890
891/**
892 * gfs2_meta_syncfs - sync all the buffers in a filesystem
893 * @sdp: the filesystem
894 *
895 */
896
897void gfs2_meta_syncfs(struct gfs2_sbd *sdp)
898{
899 gfs2_log_flush(sdp, NULL);
900 for (;;) {
901 gfs2_ail1_start(sdp);
902 gfs2_ail1_wait(sdp);
903 if (gfs2_ail1_empty(sdp))
904 break;
905 }
906 gfs2_log_flush(sdp, NULL);
907}
908
909static inline int gfs2_jrnl_flush_reqd(struct gfs2_sbd *sdp)
910{
911 return (atomic_read(&sdp->sd_log_pinned) >= atomic_read(&sdp->sd_log_thresh1));
912}
913
914static inline int gfs2_ail_flush_reqd(struct gfs2_sbd *sdp)
915{
916 unsigned int used_blocks = sdp->sd_jdesc->jd_blocks - atomic_read(&sdp->sd_log_blks_free);
917 return used_blocks >= atomic_read(&sdp->sd_log_thresh2);
918}
919
920/**
921 * gfs2_logd - Update log tail as Active Items get flushed to in-place blocks
922 * @sdp: Pointer to GFS2 superblock
923 *
924 * Also, periodically check to make sure that we're using the most recent
925 * journal index.
926 */
927
928int gfs2_logd(void *data)
929{
930 struct gfs2_sbd *sdp = data;
931 unsigned long t = 1;
932 DEFINE_WAIT(wait);
933 unsigned preflush;
934
935 while (!kthread_should_stop()) {
936
937 preflush = atomic_read(&sdp->sd_log_pinned);
938 if (gfs2_jrnl_flush_reqd(sdp) || t == 0) {
939 gfs2_ail1_empty(sdp);
940 gfs2_log_flush(sdp, NULL);
941 }
942
943 if (gfs2_ail_flush_reqd(sdp)) {
944 gfs2_ail1_start(sdp);
945 gfs2_ail1_wait(sdp);
946 gfs2_ail1_empty(sdp);
947 gfs2_log_flush(sdp, NULL);
948 }
949
950 if (!gfs2_ail_flush_reqd(sdp))
951 wake_up(&sdp->sd_log_waitq);
952
953 t = gfs2_tune_get(sdp, gt_logd_secs) * HZ;
954 if (freezing(current))
955 refrigerator();
956
957 do {
958 prepare_to_wait(&sdp->sd_logd_waitq, &wait,
959 TASK_INTERRUPTIBLE);
960 if (!gfs2_ail_flush_reqd(sdp) &&
961 !gfs2_jrnl_flush_reqd(sdp) &&
962 !kthread_should_stop())
963 t = schedule_timeout(t);
964 } while(t && !gfs2_ail_flush_reqd(sdp) &&
965 !gfs2_jrnl_flush_reqd(sdp) &&
966 !kthread_should_stop());
967 finish_wait(&sdp->sd_logd_waitq, &wait);
968 }
969
970 return 0;
971}
972
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
34/**
35 * gfs2_struct2blk - compute stuff
36 * @sdp: the filesystem
37 * @nstruct: the number of structures
38 * @ssize: the size of the structures
39 *
40 * Compute the number of log descriptor blocks needed to hold a certain number
41 * of structures of a certain size.
42 *
43 * Returns: the number of blocks needed (minimum is always 1)
44 */
45
46unsigned int gfs2_struct2blk(struct gfs2_sbd *sdp, unsigned int nstruct,
47 unsigned int ssize)
48{
49 unsigned int blks;
50 unsigned int first, second;
51
52 blks = 1;
53 first = (sdp->sd_sb.sb_bsize - sizeof(struct gfs2_log_descriptor)) / ssize;
54
55 if (nstruct > first) {
56 second = (sdp->sd_sb.sb_bsize -
57 sizeof(struct gfs2_meta_header)) / ssize;
58 blks += DIV_ROUND_UP(nstruct - first, second);
59 }
60
61 return blks;
62}
63
64/**
65 * gfs2_remove_from_ail - Remove an entry from the ail lists, updating counters
66 * @mapping: The associated mapping (maybe NULL)
67 * @bd: The gfs2_bufdata to remove
68 *
69 * The ail lock _must_ be held when calling this function
70 *
71 */
72
73static void gfs2_remove_from_ail(struct gfs2_bufdata *bd)
74{
75 bd->bd_tr = NULL;
76 list_del_init(&bd->bd_ail_st_list);
77 list_del_init(&bd->bd_ail_gl_list);
78 atomic_dec(&bd->bd_gl->gl_ail_count);
79 brelse(bd->bd_bh);
80}
81
82/**
83 * gfs2_ail1_start_one - Start I/O on a part of the AIL
84 * @sdp: the filesystem
85 * @wbc: The writeback control structure
86 * @ai: The ail structure
87 *
88 */
89
90static int gfs2_ail1_start_one(struct gfs2_sbd *sdp,
91 struct writeback_control *wbc,
92 struct gfs2_trans *tr,
93 bool *withdraw)
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
102 list_for_each_entry_safe_reverse(bd, s, &tr->tr_ail1_list, bd_ail_st_list) {
103 bh = bd->bd_bh;
104
105 gfs2_assert(sdp, bd->bd_tr == tr);
106
107 if (!buffer_busy(bh)) {
108 if (!buffer_uptodate(bh) &&
109 !test_and_set_bit(SDF_AIL1_IO_ERROR,
110 &sdp->sd_flags)) {
111 gfs2_io_error_bh(sdp, bh);
112 *withdraw = true;
113 }
114 list_move(&bd->bd_ail_st_list, &tr->tr_ail2_list);
115 continue;
116 }
117
118 if (!buffer_dirty(bh))
119 continue;
120 if (gl == bd->bd_gl)
121 continue;
122 gl = bd->bd_gl;
123 list_move(&bd->bd_ail_st_list, &tr->tr_ail1_list);
124 mapping = bh->b_page->mapping;
125 if (!mapping)
126 continue;
127 spin_unlock(&sdp->sd_ail_lock);
128 generic_writepages(mapping, wbc);
129 spin_lock(&sdp->sd_ail_lock);
130 if (wbc->nr_to_write <= 0)
131 break;
132 return 1;
133 }
134
135 return 0;
136}
137
138
139/**
140 * gfs2_ail1_flush - start writeback of some ail1 entries
141 * @sdp: The super block
142 * @wbc: The writeback control structure
143 *
144 * Writes back some ail1 entries, according to the limits in the
145 * writeback control structure
146 */
147
148void gfs2_ail1_flush(struct gfs2_sbd *sdp, struct writeback_control *wbc)
149{
150 struct list_head *head = &sdp->sd_ail1_list;
151 struct gfs2_trans *tr;
152 struct blk_plug plug;
153 bool withdraw = false;
154
155 trace_gfs2_ail_flush(sdp, wbc, 1);
156 blk_start_plug(&plug);
157 spin_lock(&sdp->sd_ail_lock);
158restart:
159 list_for_each_entry_reverse(tr, head, tr_list) {
160 if (wbc->nr_to_write <= 0)
161 break;
162 if (gfs2_ail1_start_one(sdp, wbc, tr, &withdraw))
163 goto restart;
164 }
165 spin_unlock(&sdp->sd_ail_lock);
166 blk_finish_plug(&plug);
167 if (withdraw)
168 gfs2_lm_withdraw(sdp, NULL);
169 trace_gfs2_ail_flush(sdp, wbc, 0);
170}
171
172/**
173 * gfs2_ail1_start - start writeback of all ail1 entries
174 * @sdp: The superblock
175 */
176
177static void gfs2_ail1_start(struct gfs2_sbd *sdp)
178{
179 struct writeback_control wbc = {
180 .sync_mode = WB_SYNC_NONE,
181 .nr_to_write = LONG_MAX,
182 .range_start = 0,
183 .range_end = LLONG_MAX,
184 };
185
186 return gfs2_ail1_flush(sdp, &wbc);
187}
188
189/**
190 * gfs2_ail1_empty_one - Check whether or not a trans in the AIL has been synced
191 * @sdp: the filesystem
192 * @ai: the AIL entry
193 *
194 */
195
196static void gfs2_ail1_empty_one(struct gfs2_sbd *sdp, struct gfs2_trans *tr,
197 bool *withdraw)
198{
199 struct gfs2_bufdata *bd, *s;
200 struct buffer_head *bh;
201
202 list_for_each_entry_safe_reverse(bd, s, &tr->tr_ail1_list,
203 bd_ail_st_list) {
204 bh = bd->bd_bh;
205 gfs2_assert(sdp, bd->bd_tr == tr);
206 if (buffer_busy(bh))
207 continue;
208 if (!buffer_uptodate(bh) &&
209 !test_and_set_bit(SDF_AIL1_IO_ERROR, &sdp->sd_flags)) {
210 gfs2_io_error_bh(sdp, bh);
211 *withdraw = true;
212 }
213 list_move(&bd->bd_ail_st_list, &tr->tr_ail2_list);
214 }
215}
216
217/**
218 * gfs2_ail1_empty - Try to empty the ail1 lists
219 * @sdp: The superblock
220 *
221 * Tries to empty the ail1 lists, starting with the oldest first
222 */
223
224static int gfs2_ail1_empty(struct gfs2_sbd *sdp)
225{
226 struct gfs2_trans *tr, *s;
227 int oldest_tr = 1;
228 int ret;
229 bool withdraw = false;
230
231 spin_lock(&sdp->sd_ail_lock);
232 list_for_each_entry_safe_reverse(tr, s, &sdp->sd_ail1_list, tr_list) {
233 gfs2_ail1_empty_one(sdp, tr, &withdraw);
234 if (list_empty(&tr->tr_ail1_list) && oldest_tr)
235 list_move(&tr->tr_list, &sdp->sd_ail2_list);
236 else
237 oldest_tr = 0;
238 }
239 ret = list_empty(&sdp->sd_ail1_list);
240 spin_unlock(&sdp->sd_ail_lock);
241
242 if (withdraw)
243 gfs2_lm_withdraw(sdp, "fatal: I/O error(s)\n");
244
245 return ret;
246}
247
248static void gfs2_ail1_wait(struct gfs2_sbd *sdp)
249{
250 struct gfs2_trans *tr;
251 struct gfs2_bufdata *bd;
252 struct buffer_head *bh;
253
254 spin_lock(&sdp->sd_ail_lock);
255 list_for_each_entry_reverse(tr, &sdp->sd_ail1_list, tr_list) {
256 list_for_each_entry(bd, &tr->tr_ail1_list, bd_ail_st_list) {
257 bh = bd->bd_bh;
258 if (!buffer_locked(bh))
259 continue;
260 get_bh(bh);
261 spin_unlock(&sdp->sd_ail_lock);
262 wait_on_buffer(bh);
263 brelse(bh);
264 return;
265 }
266 }
267 spin_unlock(&sdp->sd_ail_lock);
268}
269
270/**
271 * gfs2_ail2_empty_one - Check whether or not a trans in the AIL has been synced
272 * @sdp: the filesystem
273 * @ai: the AIL entry
274 *
275 */
276
277static void gfs2_ail2_empty_one(struct gfs2_sbd *sdp, struct gfs2_trans *tr)
278{
279 struct list_head *head = &tr->tr_ail2_list;
280 struct gfs2_bufdata *bd;
281
282 while (!list_empty(head)) {
283 bd = list_entry(head->prev, struct gfs2_bufdata,
284 bd_ail_st_list);
285 gfs2_assert(sdp, bd->bd_tr == tr);
286 gfs2_remove_from_ail(bd);
287 }
288}
289
290static void ail2_empty(struct gfs2_sbd *sdp, unsigned int new_tail)
291{
292 struct gfs2_trans *tr, *safe;
293 unsigned int old_tail = sdp->sd_log_tail;
294 int wrap = (new_tail < old_tail);
295 int a, b, rm;
296
297 spin_lock(&sdp->sd_ail_lock);
298
299 list_for_each_entry_safe(tr, safe, &sdp->sd_ail2_list, tr_list) {
300 a = (old_tail <= tr->tr_first);
301 b = (tr->tr_first < new_tail);
302 rm = (wrap) ? (a || b) : (a && b);
303 if (!rm)
304 continue;
305
306 gfs2_ail2_empty_one(sdp, tr);
307 list_del(&tr->tr_list);
308 gfs2_assert_warn(sdp, list_empty(&tr->tr_ail1_list));
309 gfs2_assert_warn(sdp, list_empty(&tr->tr_ail2_list));
310 kfree(tr);
311 }
312
313 spin_unlock(&sdp->sd_ail_lock);
314}
315
316/**
317 * gfs2_log_release - Release a given number of log blocks
318 * @sdp: The GFS2 superblock
319 * @blks: The number of blocks
320 *
321 */
322
323void gfs2_log_release(struct gfs2_sbd *sdp, unsigned int blks)
324{
325
326 atomic_add(blks, &sdp->sd_log_blks_free);
327 trace_gfs2_log_blocks(sdp, blks);
328 gfs2_assert_withdraw(sdp, atomic_read(&sdp->sd_log_blks_free) <=
329 sdp->sd_jdesc->jd_blocks);
330 up_read(&sdp->sd_log_flush_lock);
331}
332
333/**
334 * gfs2_log_reserve - Make a log reservation
335 * @sdp: The GFS2 superblock
336 * @blks: The number of blocks to reserve
337 *
338 * Note that we never give out the last few blocks of the journal. Thats
339 * due to the fact that there is a small number of header blocks
340 * associated with each log flush. The exact number can't be known until
341 * flush time, so we ensure that we have just enough free blocks at all
342 * times to avoid running out during a log flush.
343 *
344 * We no longer flush the log here, instead we wake up logd to do that
345 * for us. To avoid the thundering herd and to ensure that we deal fairly
346 * with queued waiters, we use an exclusive wait. This means that when we
347 * get woken with enough journal space to get our reservation, we need to
348 * wake the next waiter on the list.
349 *
350 * Returns: errno
351 */
352
353int gfs2_log_reserve(struct gfs2_sbd *sdp, unsigned int blks)
354{
355 int ret = 0;
356 unsigned reserved_blks = 7 * (4096 / sdp->sd_vfs->s_blocksize);
357 unsigned wanted = blks + reserved_blks;
358 DEFINE_WAIT(wait);
359 int did_wait = 0;
360 unsigned int free_blocks;
361
362 if (gfs2_assert_warn(sdp, blks) ||
363 gfs2_assert_warn(sdp, blks <= sdp->sd_jdesc->jd_blocks))
364 return -EINVAL;
365 atomic_add(blks, &sdp->sd_log_blks_needed);
366retry:
367 free_blocks = atomic_read(&sdp->sd_log_blks_free);
368 if (unlikely(free_blocks <= wanted)) {
369 do {
370 prepare_to_wait_exclusive(&sdp->sd_log_waitq, &wait,
371 TASK_UNINTERRUPTIBLE);
372 wake_up(&sdp->sd_logd_waitq);
373 did_wait = 1;
374 if (atomic_read(&sdp->sd_log_blks_free) <= wanted)
375 io_schedule();
376 free_blocks = atomic_read(&sdp->sd_log_blks_free);
377 } while(free_blocks <= wanted);
378 finish_wait(&sdp->sd_log_waitq, &wait);
379 }
380 atomic_inc(&sdp->sd_reserving_log);
381 if (atomic_cmpxchg(&sdp->sd_log_blks_free, free_blocks,
382 free_blocks - blks) != free_blocks) {
383 if (atomic_dec_and_test(&sdp->sd_reserving_log))
384 wake_up(&sdp->sd_reserving_log_wait);
385 goto retry;
386 }
387 atomic_sub(blks, &sdp->sd_log_blks_needed);
388 trace_gfs2_log_blocks(sdp, -blks);
389
390 /*
391 * If we waited, then so might others, wake them up _after_ we get
392 * our share of the log.
393 */
394 if (unlikely(did_wait))
395 wake_up(&sdp->sd_log_waitq);
396
397 down_read(&sdp->sd_log_flush_lock);
398 if (unlikely(!test_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags))) {
399 gfs2_log_release(sdp, blks);
400 ret = -EROFS;
401 }
402 if (atomic_dec_and_test(&sdp->sd_reserving_log))
403 wake_up(&sdp->sd_reserving_log_wait);
404 return ret;
405}
406
407/**
408 * log_distance - Compute distance between two journal blocks
409 * @sdp: The GFS2 superblock
410 * @newer: The most recent journal block of the pair
411 * @older: The older journal block of the pair
412 *
413 * Compute the distance (in the journal direction) between two
414 * blocks in the journal
415 *
416 * Returns: the distance in blocks
417 */
418
419static inline unsigned int log_distance(struct gfs2_sbd *sdp, unsigned int newer,
420 unsigned int older)
421{
422 int dist;
423
424 dist = newer - older;
425 if (dist < 0)
426 dist += sdp->sd_jdesc->jd_blocks;
427
428 return dist;
429}
430
431/**
432 * calc_reserved - Calculate the number of blocks to reserve when
433 * refunding a transaction's unused buffers.
434 * @sdp: The GFS2 superblock
435 *
436 * This is complex. We need to reserve room for all our currently used
437 * metadata buffers (e.g. normal file I/O rewriting file time stamps) and
438 * all our journaled data buffers for journaled files (e.g. files in the
439 * meta_fs like rindex, or files for which chattr +j was done.)
440 * If we don't reserve enough space, gfs2_log_refund and gfs2_log_flush
441 * will count it as free space (sd_log_blks_free) and corruption will follow.
442 *
443 * We can have metadata bufs and jdata bufs in the same journal. So each
444 * type gets its own log header, for which we need to reserve a block.
445 * In fact, each type has the potential for needing more than one header
446 * in cases where we have more buffers than will fit on a journal page.
447 * Metadata journal entries take up half the space of journaled buffer entries.
448 * Thus, metadata entries have buf_limit (502) and journaled buffers have
449 * databuf_limit (251) before they cause a wrap around.
450 *
451 * Also, we need to reserve blocks for revoke journal entries and one for an
452 * overall header for the lot.
453 *
454 * Returns: the number of blocks reserved
455 */
456static unsigned int calc_reserved(struct gfs2_sbd *sdp)
457{
458 unsigned int reserved = 0;
459 unsigned int mbuf;
460 unsigned int dbuf;
461 struct gfs2_trans *tr = sdp->sd_log_tr;
462
463 if (tr) {
464 mbuf = tr->tr_num_buf_new - tr->tr_num_buf_rm;
465 dbuf = tr->tr_num_databuf_new - tr->tr_num_databuf_rm;
466 reserved = mbuf + dbuf;
467 /* Account for header blocks */
468 reserved += DIV_ROUND_UP(mbuf, buf_limit(sdp));
469 reserved += DIV_ROUND_UP(dbuf, databuf_limit(sdp));
470 }
471
472 if (sdp->sd_log_commited_revoke > 0)
473 reserved += gfs2_struct2blk(sdp, sdp->sd_log_commited_revoke,
474 sizeof(u64));
475 /* One for the overall header */
476 if (reserved)
477 reserved++;
478 return reserved;
479}
480
481static unsigned int current_tail(struct gfs2_sbd *sdp)
482{
483 struct gfs2_trans *tr;
484 unsigned int tail;
485
486 spin_lock(&sdp->sd_ail_lock);
487
488 if (list_empty(&sdp->sd_ail1_list)) {
489 tail = sdp->sd_log_head;
490 } else {
491 tr = list_entry(sdp->sd_ail1_list.prev, struct gfs2_trans,
492 tr_list);
493 tail = tr->tr_first;
494 }
495
496 spin_unlock(&sdp->sd_ail_lock);
497
498 return tail;
499}
500
501static void log_pull_tail(struct gfs2_sbd *sdp, unsigned int new_tail)
502{
503 unsigned int dist = log_distance(sdp, new_tail, sdp->sd_log_tail);
504
505 ail2_empty(sdp, new_tail);
506
507 atomic_add(dist, &sdp->sd_log_blks_free);
508 trace_gfs2_log_blocks(sdp, dist);
509 gfs2_assert_withdraw(sdp, atomic_read(&sdp->sd_log_blks_free) <=
510 sdp->sd_jdesc->jd_blocks);
511
512 sdp->sd_log_tail = new_tail;
513}
514
515
516static void log_flush_wait(struct gfs2_sbd *sdp)
517{
518 DEFINE_WAIT(wait);
519
520 if (atomic_read(&sdp->sd_log_in_flight)) {
521 do {
522 prepare_to_wait(&sdp->sd_log_flush_wait, &wait,
523 TASK_UNINTERRUPTIBLE);
524 if (atomic_read(&sdp->sd_log_in_flight))
525 io_schedule();
526 } while(atomic_read(&sdp->sd_log_in_flight));
527 finish_wait(&sdp->sd_log_flush_wait, &wait);
528 }
529}
530
531static int ip_cmp(void *priv, struct list_head *a, struct list_head *b)
532{
533 struct gfs2_inode *ipa, *ipb;
534
535 ipa = list_entry(a, struct gfs2_inode, i_ordered);
536 ipb = list_entry(b, struct gfs2_inode, i_ordered);
537
538 if (ipa->i_no_addr < ipb->i_no_addr)
539 return -1;
540 if (ipa->i_no_addr > ipb->i_no_addr)
541 return 1;
542 return 0;
543}
544
545static void gfs2_ordered_write(struct gfs2_sbd *sdp)
546{
547 struct gfs2_inode *ip;
548 LIST_HEAD(written);
549
550 spin_lock(&sdp->sd_ordered_lock);
551 list_sort(NULL, &sdp->sd_log_ordered, &ip_cmp);
552 while (!list_empty(&sdp->sd_log_ordered)) {
553 ip = list_entry(sdp->sd_log_ordered.next, struct gfs2_inode, i_ordered);
554 if (ip->i_inode.i_mapping->nrpages == 0) {
555 test_and_clear_bit(GIF_ORDERED, &ip->i_flags);
556 list_del(&ip->i_ordered);
557 continue;
558 }
559 list_move(&ip->i_ordered, &written);
560 spin_unlock(&sdp->sd_ordered_lock);
561 filemap_fdatawrite(ip->i_inode.i_mapping);
562 spin_lock(&sdp->sd_ordered_lock);
563 }
564 list_splice(&written, &sdp->sd_log_ordered);
565 spin_unlock(&sdp->sd_ordered_lock);
566}
567
568static void gfs2_ordered_wait(struct gfs2_sbd *sdp)
569{
570 struct gfs2_inode *ip;
571
572 spin_lock(&sdp->sd_ordered_lock);
573 while (!list_empty(&sdp->sd_log_ordered)) {
574 ip = list_entry(sdp->sd_log_ordered.next, struct gfs2_inode, i_ordered);
575 list_del(&ip->i_ordered);
576 WARN_ON(!test_and_clear_bit(GIF_ORDERED, &ip->i_flags));
577 if (ip->i_inode.i_mapping->nrpages == 0)
578 continue;
579 spin_unlock(&sdp->sd_ordered_lock);
580 filemap_fdatawait(ip->i_inode.i_mapping);
581 spin_lock(&sdp->sd_ordered_lock);
582 }
583 spin_unlock(&sdp->sd_ordered_lock);
584}
585
586void gfs2_ordered_del_inode(struct gfs2_inode *ip)
587{
588 struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
589
590 spin_lock(&sdp->sd_ordered_lock);
591 if (test_and_clear_bit(GIF_ORDERED, &ip->i_flags))
592 list_del(&ip->i_ordered);
593 spin_unlock(&sdp->sd_ordered_lock);
594}
595
596void gfs2_add_revoke(struct gfs2_sbd *sdp, struct gfs2_bufdata *bd)
597{
598 struct buffer_head *bh = bd->bd_bh;
599 struct gfs2_glock *gl = bd->bd_gl;
600
601 bh->b_private = NULL;
602 bd->bd_blkno = bh->b_blocknr;
603 gfs2_remove_from_ail(bd); /* drops ref on bh */
604 bd->bd_bh = NULL;
605 sdp->sd_log_num_revoke++;
606 if (atomic_inc_return(&gl->gl_revokes) == 1)
607 gfs2_glock_hold(gl);
608 set_bit(GLF_LFLUSH, &gl->gl_flags);
609 list_add(&bd->bd_list, &sdp->sd_log_revokes);
610}
611
612void gfs2_write_revokes(struct gfs2_sbd *sdp)
613{
614 struct gfs2_trans *tr;
615 struct gfs2_bufdata *bd, *tmp;
616 int have_revokes = 0;
617 int max_revokes = (sdp->sd_sb.sb_bsize - sizeof(struct gfs2_log_descriptor)) / sizeof(u64);
618
619 gfs2_ail1_empty(sdp);
620 spin_lock(&sdp->sd_ail_lock);
621 list_for_each_entry_reverse(tr, &sdp->sd_ail1_list, tr_list) {
622 list_for_each_entry(bd, &tr->tr_ail2_list, bd_ail_st_list) {
623 if (list_empty(&bd->bd_list)) {
624 have_revokes = 1;
625 goto done;
626 }
627 }
628 }
629done:
630 spin_unlock(&sdp->sd_ail_lock);
631 if (have_revokes == 0)
632 return;
633 while (sdp->sd_log_num_revoke > max_revokes)
634 max_revokes += (sdp->sd_sb.sb_bsize - sizeof(struct gfs2_meta_header)) / sizeof(u64);
635 max_revokes -= sdp->sd_log_num_revoke;
636 if (!sdp->sd_log_num_revoke) {
637 atomic_dec(&sdp->sd_log_blks_free);
638 /* If no blocks have been reserved, we need to also
639 * reserve a block for the header */
640 if (!sdp->sd_log_blks_reserved)
641 atomic_dec(&sdp->sd_log_blks_free);
642 }
643 gfs2_log_lock(sdp);
644 spin_lock(&sdp->sd_ail_lock);
645 list_for_each_entry_reverse(tr, &sdp->sd_ail1_list, tr_list) {
646 list_for_each_entry_safe(bd, tmp, &tr->tr_ail2_list, bd_ail_st_list) {
647 if (max_revokes == 0)
648 goto out_of_blocks;
649 if (!list_empty(&bd->bd_list))
650 continue;
651 gfs2_add_revoke(sdp, bd);
652 max_revokes--;
653 }
654 }
655out_of_blocks:
656 spin_unlock(&sdp->sd_ail_lock);
657 gfs2_log_unlock(sdp);
658
659 if (!sdp->sd_log_num_revoke) {
660 atomic_inc(&sdp->sd_log_blks_free);
661 if (!sdp->sd_log_blks_reserved)
662 atomic_inc(&sdp->sd_log_blks_free);
663 }
664}
665
666/**
667 * gfs2_write_log_header - Write a journal log header buffer at lblock
668 * @sdp: The GFS2 superblock
669 * @jd: journal descriptor of the journal to which we are writing
670 * @seq: sequence number
671 * @tail: tail of the log
672 * @lblock: value for lh_blkno (block number relative to start of journal)
673 * @flags: log header flags GFS2_LOG_HEAD_*
674 * @op_flags: flags to pass to the bio
675 *
676 * Returns: the initialized log buffer descriptor
677 */
678
679void gfs2_write_log_header(struct gfs2_sbd *sdp, struct gfs2_jdesc *jd,
680 u64 seq, u32 tail, u32 lblock, u32 flags,
681 int op_flags)
682{
683 struct gfs2_log_header *lh;
684 u32 hash, crc;
685 struct page *page = mempool_alloc(gfs2_page_pool, GFP_NOIO);
686 struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
687 struct timespec64 tv;
688 struct super_block *sb = sdp->sd_vfs;
689 u64 dblock;
690
691 lh = page_address(page);
692 clear_page(lh);
693
694 lh->lh_header.mh_magic = cpu_to_be32(GFS2_MAGIC);
695 lh->lh_header.mh_type = cpu_to_be32(GFS2_METATYPE_LH);
696 lh->lh_header.__pad0 = cpu_to_be64(0);
697 lh->lh_header.mh_format = cpu_to_be32(GFS2_FORMAT_LH);
698 lh->lh_header.mh_jid = cpu_to_be32(sdp->sd_jdesc->jd_jid);
699 lh->lh_sequence = cpu_to_be64(seq);
700 lh->lh_flags = cpu_to_be32(flags);
701 lh->lh_tail = cpu_to_be32(tail);
702 lh->lh_blkno = cpu_to_be32(lblock);
703 hash = ~crc32(~0, lh, LH_V1_SIZE);
704 lh->lh_hash = cpu_to_be32(hash);
705
706 ktime_get_coarse_real_ts64(&tv);
707 lh->lh_nsec = cpu_to_be32(tv.tv_nsec);
708 lh->lh_sec = cpu_to_be64(tv.tv_sec);
709 if (!list_empty(&jd->extent_list))
710 dblock = gfs2_log_bmap(sdp);
711 else {
712 int ret = gfs2_lblk_to_dblk(jd->jd_inode, lblock, &dblock);
713 if (gfs2_assert_withdraw(sdp, ret == 0))
714 return;
715 }
716 lh->lh_addr = cpu_to_be64(dblock);
717 lh->lh_jinode = cpu_to_be64(GFS2_I(jd->jd_inode)->i_no_addr);
718
719 /* We may only write local statfs, quota, etc., when writing to our
720 own journal. The values are left 0 when recovering a journal
721 different from our own. */
722 if (!(flags & GFS2_LOG_HEAD_RECOVERY)) {
723 lh->lh_statfs_addr =
724 cpu_to_be64(GFS2_I(sdp->sd_sc_inode)->i_no_addr);
725 lh->lh_quota_addr =
726 cpu_to_be64(GFS2_I(sdp->sd_qc_inode)->i_no_addr);
727
728 spin_lock(&sdp->sd_statfs_spin);
729 lh->lh_local_total = cpu_to_be64(l_sc->sc_total);
730 lh->lh_local_free = cpu_to_be64(l_sc->sc_free);
731 lh->lh_local_dinodes = cpu_to_be64(l_sc->sc_dinodes);
732 spin_unlock(&sdp->sd_statfs_spin);
733 }
734
735 BUILD_BUG_ON(offsetof(struct gfs2_log_header, lh_crc) != LH_V1_SIZE);
736
737 crc = crc32c(~0, (void *)lh + LH_V1_SIZE + 4,
738 sb->s_blocksize - LH_V1_SIZE - 4);
739 lh->lh_crc = cpu_to_be32(crc);
740
741 gfs2_log_write(sdp, page, sb->s_blocksize, 0, dblock);
742 gfs2_log_submit_bio(&sdp->sd_log_bio, REQ_OP_WRITE | op_flags);
743 log_flush_wait(sdp);
744}
745
746/**
747 * log_write_header - Get and initialize a journal header buffer
748 * @sdp: The GFS2 superblock
749 * @flags: The log header flags, including log header origin
750 *
751 * Returns: the initialized log buffer descriptor
752 */
753
754static void log_write_header(struct gfs2_sbd *sdp, u32 flags)
755{
756 unsigned int tail;
757 int op_flags = REQ_PREFLUSH | REQ_FUA | REQ_META | REQ_SYNC;
758 enum gfs2_freeze_state state = atomic_read(&sdp->sd_freeze_state);
759
760 gfs2_assert_withdraw(sdp, (state != SFS_FROZEN));
761 tail = current_tail(sdp);
762
763 if (test_bit(SDF_NOBARRIERS, &sdp->sd_flags)) {
764 gfs2_ordered_wait(sdp);
765 log_flush_wait(sdp);
766 op_flags = REQ_SYNC | REQ_META | REQ_PRIO;
767 }
768 sdp->sd_log_idle = (tail == sdp->sd_log_flush_head);
769 gfs2_write_log_header(sdp, sdp->sd_jdesc, sdp->sd_log_sequence++, tail,
770 sdp->sd_log_flush_head, flags, op_flags);
771
772 if (sdp->sd_log_tail != tail)
773 log_pull_tail(sdp, tail);
774}
775
776/**
777 * gfs2_log_flush - flush incore transaction(s)
778 * @sdp: the filesystem
779 * @gl: The glock structure to flush. If NULL, flush the whole incore log
780 * @flags: The log header flags: GFS2_LOG_HEAD_FLUSH_* and debug flags
781 *
782 */
783
784void gfs2_log_flush(struct gfs2_sbd *sdp, struct gfs2_glock *gl, u32 flags)
785{
786 struct gfs2_trans *tr;
787 enum gfs2_freeze_state state = atomic_read(&sdp->sd_freeze_state);
788
789 down_write(&sdp->sd_log_flush_lock);
790
791 /* Log might have been flushed while we waited for the flush lock */
792 if (gl && !test_bit(GLF_LFLUSH, &gl->gl_flags)) {
793 up_write(&sdp->sd_log_flush_lock);
794 return;
795 }
796 trace_gfs2_log_flush(sdp, 1, flags);
797
798 if (flags & GFS2_LOG_HEAD_FLUSH_SHUTDOWN)
799 clear_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags);
800
801 sdp->sd_log_flush_head = sdp->sd_log_head;
802 tr = sdp->sd_log_tr;
803 if (tr) {
804 sdp->sd_log_tr = NULL;
805 INIT_LIST_HEAD(&tr->tr_ail1_list);
806 INIT_LIST_HEAD(&tr->tr_ail2_list);
807 tr->tr_first = sdp->sd_log_flush_head;
808 if (unlikely (state == SFS_FROZEN))
809 gfs2_assert_withdraw(sdp, !tr->tr_num_buf_new && !tr->tr_num_databuf_new);
810 }
811
812 if (unlikely(state == SFS_FROZEN))
813 gfs2_assert_withdraw(sdp, !sdp->sd_log_num_revoke);
814 gfs2_assert_withdraw(sdp,
815 sdp->sd_log_num_revoke == sdp->sd_log_commited_revoke);
816
817 gfs2_ordered_write(sdp);
818 lops_before_commit(sdp, tr);
819 gfs2_log_submit_bio(&sdp->sd_log_bio, REQ_OP_WRITE);
820
821 if (sdp->sd_log_head != sdp->sd_log_flush_head) {
822 log_flush_wait(sdp);
823 log_write_header(sdp, flags);
824 } else if (sdp->sd_log_tail != current_tail(sdp) && !sdp->sd_log_idle){
825 atomic_dec(&sdp->sd_log_blks_free); /* Adjust for unreserved buffer */
826 trace_gfs2_log_blocks(sdp, -1);
827 log_write_header(sdp, flags);
828 }
829 lops_after_commit(sdp, tr);
830
831 gfs2_log_lock(sdp);
832 sdp->sd_log_head = sdp->sd_log_flush_head;
833 sdp->sd_log_blks_reserved = 0;
834 sdp->sd_log_commited_revoke = 0;
835
836 spin_lock(&sdp->sd_ail_lock);
837 if (tr && !list_empty(&tr->tr_ail1_list)) {
838 list_add(&tr->tr_list, &sdp->sd_ail1_list);
839 tr = NULL;
840 }
841 spin_unlock(&sdp->sd_ail_lock);
842 gfs2_log_unlock(sdp);
843
844 if (!(flags & GFS2_LOG_HEAD_FLUSH_NORMAL)) {
845 if (!sdp->sd_log_idle) {
846 for (;;) {
847 gfs2_ail1_start(sdp);
848 gfs2_ail1_wait(sdp);
849 if (gfs2_ail1_empty(sdp))
850 break;
851 }
852 atomic_dec(&sdp->sd_log_blks_free); /* Adjust for unreserved buffer */
853 trace_gfs2_log_blocks(sdp, -1);
854 log_write_header(sdp, flags);
855 sdp->sd_log_head = sdp->sd_log_flush_head;
856 }
857 if (flags & (GFS2_LOG_HEAD_FLUSH_SHUTDOWN |
858 GFS2_LOG_HEAD_FLUSH_FREEZE))
859 gfs2_log_shutdown(sdp);
860 if (flags & GFS2_LOG_HEAD_FLUSH_FREEZE)
861 atomic_set(&sdp->sd_freeze_state, SFS_FROZEN);
862 }
863
864 trace_gfs2_log_flush(sdp, 0, flags);
865 up_write(&sdp->sd_log_flush_lock);
866
867 kfree(tr);
868}
869
870/**
871 * gfs2_merge_trans - Merge a new transaction into a cached transaction
872 * @old: Original transaction to be expanded
873 * @new: New transaction to be merged
874 */
875
876static void gfs2_merge_trans(struct gfs2_trans *old, struct gfs2_trans *new)
877{
878 WARN_ON_ONCE(!test_bit(TR_ATTACHED, &old->tr_flags));
879
880 old->tr_num_buf_new += new->tr_num_buf_new;
881 old->tr_num_databuf_new += new->tr_num_databuf_new;
882 old->tr_num_buf_rm += new->tr_num_buf_rm;
883 old->tr_num_databuf_rm += new->tr_num_databuf_rm;
884 old->tr_num_revoke += new->tr_num_revoke;
885
886 list_splice_tail_init(&new->tr_databuf, &old->tr_databuf);
887 list_splice_tail_init(&new->tr_buf, &old->tr_buf);
888}
889
890static void log_refund(struct gfs2_sbd *sdp, struct gfs2_trans *tr)
891{
892 unsigned int reserved;
893 unsigned int unused;
894 unsigned int maxres;
895
896 gfs2_log_lock(sdp);
897
898 if (sdp->sd_log_tr) {
899 gfs2_merge_trans(sdp->sd_log_tr, tr);
900 } else if (tr->tr_num_buf_new || tr->tr_num_databuf_new) {
901 gfs2_assert_withdraw(sdp, test_bit(TR_ALLOCED, &tr->tr_flags));
902 sdp->sd_log_tr = tr;
903 set_bit(TR_ATTACHED, &tr->tr_flags);
904 }
905
906 sdp->sd_log_commited_revoke += tr->tr_num_revoke;
907 reserved = calc_reserved(sdp);
908 maxres = sdp->sd_log_blks_reserved + tr->tr_reserved;
909 gfs2_assert_withdraw(sdp, maxres >= reserved);
910 unused = maxres - reserved;
911 atomic_add(unused, &sdp->sd_log_blks_free);
912 trace_gfs2_log_blocks(sdp, unused);
913 gfs2_assert_withdraw(sdp, atomic_read(&sdp->sd_log_blks_free) <=
914 sdp->sd_jdesc->jd_blocks);
915 sdp->sd_log_blks_reserved = reserved;
916
917 gfs2_log_unlock(sdp);
918}
919
920/**
921 * gfs2_log_commit - Commit a transaction to the log
922 * @sdp: the filesystem
923 * @tr: the transaction
924 *
925 * We wake up gfs2_logd if the number of pinned blocks exceed thresh1
926 * or the total number of used blocks (pinned blocks plus AIL blocks)
927 * is greater than thresh2.
928 *
929 * At mount time thresh1 is 1/3rd of journal size, thresh2 is 2/3rd of
930 * journal size.
931 *
932 * Returns: errno
933 */
934
935void gfs2_log_commit(struct gfs2_sbd *sdp, struct gfs2_trans *tr)
936{
937 log_refund(sdp, tr);
938
939 if (atomic_read(&sdp->sd_log_pinned) > atomic_read(&sdp->sd_log_thresh1) ||
940 ((sdp->sd_jdesc->jd_blocks - atomic_read(&sdp->sd_log_blks_free)) >
941 atomic_read(&sdp->sd_log_thresh2)))
942 wake_up(&sdp->sd_logd_waitq);
943}
944
945/**
946 * gfs2_log_shutdown - write a shutdown header into a journal
947 * @sdp: the filesystem
948 *
949 */
950
951void gfs2_log_shutdown(struct gfs2_sbd *sdp)
952{
953 gfs2_assert_withdraw(sdp, !sdp->sd_log_blks_reserved);
954 gfs2_assert_withdraw(sdp, !sdp->sd_log_num_revoke);
955 gfs2_assert_withdraw(sdp, list_empty(&sdp->sd_ail1_list));
956
957 sdp->sd_log_flush_head = sdp->sd_log_head;
958
959 log_write_header(sdp, GFS2_LOG_HEAD_UNMOUNT | GFS2_LFC_SHUTDOWN);
960
961 gfs2_assert_warn(sdp, sdp->sd_log_head == sdp->sd_log_tail);
962 gfs2_assert_warn(sdp, list_empty(&sdp->sd_ail2_list));
963
964 sdp->sd_log_head = sdp->sd_log_flush_head;
965 sdp->sd_log_tail = sdp->sd_log_head;
966}
967
968static inline int gfs2_jrnl_flush_reqd(struct gfs2_sbd *sdp)
969{
970 return (atomic_read(&sdp->sd_log_pinned) +
971 atomic_read(&sdp->sd_log_blks_needed) >=
972 atomic_read(&sdp->sd_log_thresh1));
973}
974
975static inline int gfs2_ail_flush_reqd(struct gfs2_sbd *sdp)
976{
977 unsigned int used_blocks = sdp->sd_jdesc->jd_blocks - atomic_read(&sdp->sd_log_blks_free);
978
979 if (test_and_clear_bit(SDF_FORCE_AIL_FLUSH, &sdp->sd_flags))
980 return 1;
981
982 return used_blocks + atomic_read(&sdp->sd_log_blks_needed) >=
983 atomic_read(&sdp->sd_log_thresh2);
984}
985
986/**
987 * gfs2_logd - Update log tail as Active Items get flushed to in-place blocks
988 * @sdp: Pointer to GFS2 superblock
989 *
990 * Also, periodically check to make sure that we're using the most recent
991 * journal index.
992 */
993
994int gfs2_logd(void *data)
995{
996 struct gfs2_sbd *sdp = data;
997 unsigned long t = 1;
998 DEFINE_WAIT(wait);
999 bool did_flush;
1000
1001 while (!kthread_should_stop()) {
1002
1003 /* Check for errors writing to the journal */
1004 if (sdp->sd_log_error) {
1005 gfs2_lm_withdraw(sdp,
1006 "GFS2: fsid=%s: error %d: "
1007 "withdrawing the file system to "
1008 "prevent further damage.\n",
1009 sdp->sd_fsname, sdp->sd_log_error);
1010 }
1011
1012 did_flush = false;
1013 if (gfs2_jrnl_flush_reqd(sdp) || t == 0) {
1014 gfs2_ail1_empty(sdp);
1015 gfs2_log_flush(sdp, NULL, GFS2_LOG_HEAD_FLUSH_NORMAL |
1016 GFS2_LFC_LOGD_JFLUSH_REQD);
1017 did_flush = true;
1018 }
1019
1020 if (gfs2_ail_flush_reqd(sdp)) {
1021 gfs2_ail1_start(sdp);
1022 gfs2_ail1_wait(sdp);
1023 gfs2_ail1_empty(sdp);
1024 gfs2_log_flush(sdp, NULL, GFS2_LOG_HEAD_FLUSH_NORMAL |
1025 GFS2_LFC_LOGD_AIL_FLUSH_REQD);
1026 did_flush = true;
1027 }
1028
1029 if (!gfs2_ail_flush_reqd(sdp) || did_flush)
1030 wake_up(&sdp->sd_log_waitq);
1031
1032 t = gfs2_tune_get(sdp, gt_logd_secs) * HZ;
1033
1034 try_to_freeze();
1035
1036 do {
1037 prepare_to_wait(&sdp->sd_logd_waitq, &wait,
1038 TASK_INTERRUPTIBLE);
1039 if (!gfs2_ail_flush_reqd(sdp) &&
1040 !gfs2_jrnl_flush_reqd(sdp) &&
1041 !kthread_should_stop())
1042 t = schedule_timeout(t);
1043 } while(t && !gfs2_ail_flush_reqd(sdp) &&
1044 !gfs2_jrnl_flush_reqd(sdp) &&
1045 !kthread_should_stop());
1046 finish_wait(&sdp->sd_logd_waitq, &wait);
1047 }
1048
1049 return 0;
1050}
1051