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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/*
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/crc32c.h>
18#include <linux/delay.h>
19#include <linux/kthread.h>
20#include <linux/freezer.h>
21#include <linux/bio.h>
22#include <linux/blkdev.h>
23#include <linux/writeback.h>
24#include <linux/list_sort.h>
25
26#include "gfs2.h"
27#include "incore.h"
28#include "bmap.h"
29#include "glock.h"
30#include "log.h"
31#include "lops.h"
32#include "meta_io.h"
33#include "util.h"
34#include "dir.h"
35#include "trace_gfs2.h"
36
37/**
38 * gfs2_struct2blk - compute stuff
39 * @sdp: the filesystem
40 * @nstruct: the number of structures
41 * @ssize: the size of the structures
42 *
43 * Compute the number of log descriptor blocks needed to hold a certain number
44 * of structures of a certain size.
45 *
46 * Returns: the number of blocks needed (minimum is always 1)
47 */
48
49unsigned int gfs2_struct2blk(struct gfs2_sbd *sdp, unsigned int nstruct,
50 unsigned int ssize)
51{
52 unsigned int blks;
53 unsigned int first, second;
54
55 blks = 1;
56 first = (sdp->sd_sb.sb_bsize - sizeof(struct gfs2_log_descriptor)) / ssize;
57
58 if (nstruct > first) {
59 second = (sdp->sd_sb.sb_bsize -
60 sizeof(struct gfs2_meta_header)) / ssize;
61 blks += DIV_ROUND_UP(nstruct - first, second);
62 }
63
64 return blks;
65}
66
67/**
68 * gfs2_remove_from_ail - Remove an entry from the ail lists, updating counters
69 * @mapping: The associated mapping (maybe NULL)
70 * @bd: The gfs2_bufdata to remove
71 *
72 * The ail lock _must_ be held when calling this function
73 *
74 */
75
76static void gfs2_remove_from_ail(struct gfs2_bufdata *bd)
77{
78 bd->bd_tr = NULL;
79 list_del_init(&bd->bd_ail_st_list);
80 list_del_init(&bd->bd_ail_gl_list);
81 atomic_dec(&bd->bd_gl->gl_ail_count);
82 brelse(bd->bd_bh);
83}
84
85/**
86 * gfs2_ail1_start_one - Start I/O on a part of the AIL
87 * @sdp: the filesystem
88 * @wbc: The writeback control structure
89 * @ai: The ail structure
90 *
91 */
92
93static int gfs2_ail1_start_one(struct gfs2_sbd *sdp,
94 struct writeback_control *wbc,
95 struct gfs2_trans *tr)
96__releases(&sdp->sd_ail_lock)
97__acquires(&sdp->sd_ail_lock)
98{
99 struct gfs2_glock *gl = NULL;
100 struct address_space *mapping;
101 struct gfs2_bufdata *bd, *s;
102 struct buffer_head *bh;
103
104 list_for_each_entry_safe_reverse(bd, s, &tr->tr_ail1_list, bd_ail_st_list) {
105 bh = bd->bd_bh;
106
107 gfs2_assert(sdp, bd->bd_tr == tr);
108
109 if (!buffer_busy(bh)) {
110 if (!buffer_uptodate(bh))
111 gfs2_io_error_bh(sdp, bh);
112 list_move(&bd->bd_ail_st_list, &tr->tr_ail2_list);
113 continue;
114 }
115
116 if (!buffer_dirty(bh))
117 continue;
118 if (gl == bd->bd_gl)
119 continue;
120 gl = bd->bd_gl;
121 list_move(&bd->bd_ail_st_list, &tr->tr_ail1_list);
122 mapping = bh->b_page->mapping;
123 if (!mapping)
124 continue;
125 spin_unlock(&sdp->sd_ail_lock);
126 generic_writepages(mapping, wbc);
127 spin_lock(&sdp->sd_ail_lock);
128 if (wbc->nr_to_write <= 0)
129 break;
130 return 1;
131 }
132
133 return 0;
134}
135
136
137/**
138 * gfs2_ail1_flush - start writeback of some ail1 entries
139 * @sdp: The super block
140 * @wbc: The writeback control structure
141 *
142 * Writes back some ail1 entries, according to the limits in the
143 * writeback control structure
144 */
145
146void gfs2_ail1_flush(struct gfs2_sbd *sdp, struct writeback_control *wbc)
147{
148 struct list_head *head = &sdp->sd_ail1_list;
149 struct gfs2_trans *tr;
150 struct blk_plug plug;
151
152 trace_gfs2_ail_flush(sdp, wbc, 1);
153 blk_start_plug(&plug);
154 spin_lock(&sdp->sd_ail_lock);
155restart:
156 list_for_each_entry_reverse(tr, head, tr_list) {
157 if (wbc->nr_to_write <= 0)
158 break;
159 if (gfs2_ail1_start_one(sdp, wbc, tr))
160 goto restart;
161 }
162 spin_unlock(&sdp->sd_ail_lock);
163 blk_finish_plug(&plug);
164 trace_gfs2_ail_flush(sdp, wbc, 0);
165}
166
167/**
168 * gfs2_ail1_start - start writeback of all ail1 entries
169 * @sdp: The superblock
170 */
171
172static void gfs2_ail1_start(struct gfs2_sbd *sdp)
173{
174 struct writeback_control wbc = {
175 .sync_mode = WB_SYNC_NONE,
176 .nr_to_write = LONG_MAX,
177 .range_start = 0,
178 .range_end = LLONG_MAX,
179 };
180
181 return gfs2_ail1_flush(sdp, &wbc);
182}
183
184/**
185 * gfs2_ail1_empty_one - Check whether or not a trans in the AIL has been synced
186 * @sdp: the filesystem
187 * @ai: the AIL entry
188 *
189 */
190
191static void gfs2_ail1_empty_one(struct gfs2_sbd *sdp, struct gfs2_trans *tr)
192{
193 struct gfs2_bufdata *bd, *s;
194 struct buffer_head *bh;
195
196 list_for_each_entry_safe_reverse(bd, s, &tr->tr_ail1_list,
197 bd_ail_st_list) {
198 bh = bd->bd_bh;
199 gfs2_assert(sdp, bd->bd_tr == tr);
200 if (buffer_busy(bh))
201 continue;
202 if (!buffer_uptodate(bh))
203 gfs2_io_error_bh(sdp, bh);
204 list_move(&bd->bd_ail_st_list, &tr->tr_ail2_list);
205 }
206
207}
208
209/**
210 * gfs2_ail1_empty - Try to empty the ail1 lists
211 * @sdp: The superblock
212 *
213 * Tries to empty the ail1 lists, starting with the oldest first
214 */
215
216static int gfs2_ail1_empty(struct gfs2_sbd *sdp)
217{
218 struct gfs2_trans *tr, *s;
219 int oldest_tr = 1;
220 int ret;
221
222 spin_lock(&sdp->sd_ail_lock);
223 list_for_each_entry_safe_reverse(tr, s, &sdp->sd_ail1_list, tr_list) {
224 gfs2_ail1_empty_one(sdp, tr);
225 if (list_empty(&tr->tr_ail1_list) && oldest_tr)
226 list_move(&tr->tr_list, &sdp->sd_ail2_list);
227 else
228 oldest_tr = 0;
229 }
230 ret = list_empty(&sdp->sd_ail1_list);
231 spin_unlock(&sdp->sd_ail_lock);
232
233 return ret;
234}
235
236static void gfs2_ail1_wait(struct gfs2_sbd *sdp)
237{
238 struct gfs2_trans *tr;
239 struct gfs2_bufdata *bd;
240 struct buffer_head *bh;
241
242 spin_lock(&sdp->sd_ail_lock);
243 list_for_each_entry_reverse(tr, &sdp->sd_ail1_list, tr_list) {
244 list_for_each_entry(bd, &tr->tr_ail1_list, bd_ail_st_list) {
245 bh = bd->bd_bh;
246 if (!buffer_locked(bh))
247 continue;
248 get_bh(bh);
249 spin_unlock(&sdp->sd_ail_lock);
250 wait_on_buffer(bh);
251 brelse(bh);
252 return;
253 }
254 }
255 spin_unlock(&sdp->sd_ail_lock);
256}
257
258/**
259 * gfs2_ail2_empty_one - Check whether or not a trans in the AIL has been synced
260 * @sdp: the filesystem
261 * @ai: the AIL entry
262 *
263 */
264
265static void gfs2_ail2_empty_one(struct gfs2_sbd *sdp, struct gfs2_trans *tr)
266{
267 struct list_head *head = &tr->tr_ail2_list;
268 struct gfs2_bufdata *bd;
269
270 while (!list_empty(head)) {
271 bd = list_entry(head->prev, struct gfs2_bufdata,
272 bd_ail_st_list);
273 gfs2_assert(sdp, bd->bd_tr == tr);
274 gfs2_remove_from_ail(bd);
275 }
276}
277
278static void ail2_empty(struct gfs2_sbd *sdp, unsigned int new_tail)
279{
280 struct gfs2_trans *tr, *safe;
281 unsigned int old_tail = sdp->sd_log_tail;
282 int wrap = (new_tail < old_tail);
283 int a, b, rm;
284
285 spin_lock(&sdp->sd_ail_lock);
286
287 list_for_each_entry_safe(tr, safe, &sdp->sd_ail2_list, tr_list) {
288 a = (old_tail <= tr->tr_first);
289 b = (tr->tr_first < new_tail);
290 rm = (wrap) ? (a || b) : (a && b);
291 if (!rm)
292 continue;
293
294 gfs2_ail2_empty_one(sdp, tr);
295 list_del(&tr->tr_list);
296 gfs2_assert_warn(sdp, list_empty(&tr->tr_ail1_list));
297 gfs2_assert_warn(sdp, list_empty(&tr->tr_ail2_list));
298 kfree(tr);
299 }
300
301 spin_unlock(&sdp->sd_ail_lock);
302}
303
304/**
305 * gfs2_log_release - Release a given number of log blocks
306 * @sdp: The GFS2 superblock
307 * @blks: The number of blocks
308 *
309 */
310
311void gfs2_log_release(struct gfs2_sbd *sdp, unsigned int blks)
312{
313
314 atomic_add(blks, &sdp->sd_log_blks_free);
315 trace_gfs2_log_blocks(sdp, blks);
316 gfs2_assert_withdraw(sdp, atomic_read(&sdp->sd_log_blks_free) <=
317 sdp->sd_jdesc->jd_blocks);
318 up_read(&sdp->sd_log_flush_lock);
319}
320
321/**
322 * gfs2_log_reserve - Make a log reservation
323 * @sdp: The GFS2 superblock
324 * @blks: The number of blocks to reserve
325 *
326 * Note that we never give out the last few blocks of the journal. Thats
327 * due to the fact that there is a small number of header blocks
328 * associated with each log flush. The exact number can't be known until
329 * flush time, so we ensure that we have just enough free blocks at all
330 * times to avoid running out during a log flush.
331 *
332 * We no longer flush the log here, instead we wake up logd to do that
333 * for us. To avoid the thundering herd and to ensure that we deal fairly
334 * with queued waiters, we use an exclusive wait. This means that when we
335 * get woken with enough journal space to get our reservation, we need to
336 * wake the next waiter on the list.
337 *
338 * Returns: errno
339 */
340
341int gfs2_log_reserve(struct gfs2_sbd *sdp, unsigned int blks)
342{
343 int ret = 0;
344 unsigned reserved_blks = 7 * (4096 / sdp->sd_vfs->s_blocksize);
345 unsigned wanted = blks + reserved_blks;
346 DEFINE_WAIT(wait);
347 int did_wait = 0;
348 unsigned int free_blocks;
349
350 if (gfs2_assert_warn(sdp, blks) ||
351 gfs2_assert_warn(sdp, blks <= sdp->sd_jdesc->jd_blocks))
352 return -EINVAL;
353 atomic_add(blks, &sdp->sd_log_blks_needed);
354retry:
355 free_blocks = atomic_read(&sdp->sd_log_blks_free);
356 if (unlikely(free_blocks <= wanted)) {
357 do {
358 prepare_to_wait_exclusive(&sdp->sd_log_waitq, &wait,
359 TASK_UNINTERRUPTIBLE);
360 wake_up(&sdp->sd_logd_waitq);
361 did_wait = 1;
362 if (atomic_read(&sdp->sd_log_blks_free) <= wanted)
363 io_schedule();
364 free_blocks = atomic_read(&sdp->sd_log_blks_free);
365 } while(free_blocks <= wanted);
366 finish_wait(&sdp->sd_log_waitq, &wait);
367 }
368 atomic_inc(&sdp->sd_reserving_log);
369 if (atomic_cmpxchg(&sdp->sd_log_blks_free, free_blocks,
370 free_blocks - blks) != free_blocks) {
371 if (atomic_dec_and_test(&sdp->sd_reserving_log))
372 wake_up(&sdp->sd_reserving_log_wait);
373 goto retry;
374 }
375 atomic_sub(blks, &sdp->sd_log_blks_needed);
376 trace_gfs2_log_blocks(sdp, -blks);
377
378 /*
379 * If we waited, then so might others, wake them up _after_ we get
380 * our share of the log.
381 */
382 if (unlikely(did_wait))
383 wake_up(&sdp->sd_log_waitq);
384
385 down_read(&sdp->sd_log_flush_lock);
386 if (unlikely(!test_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags))) {
387 gfs2_log_release(sdp, blks);
388 ret = -EROFS;
389 }
390 if (atomic_dec_and_test(&sdp->sd_reserving_log))
391 wake_up(&sdp->sd_reserving_log_wait);
392 return ret;
393}
394
395/**
396 * log_distance - Compute distance between two journal blocks
397 * @sdp: The GFS2 superblock
398 * @newer: The most recent journal block of the pair
399 * @older: The older journal block of the pair
400 *
401 * Compute the distance (in the journal direction) between two
402 * blocks in the journal
403 *
404 * Returns: the distance in blocks
405 */
406
407static inline unsigned int log_distance(struct gfs2_sbd *sdp, unsigned int newer,
408 unsigned int older)
409{
410 int dist;
411
412 dist = newer - older;
413 if (dist < 0)
414 dist += sdp->sd_jdesc->jd_blocks;
415
416 return dist;
417}
418
419/**
420 * calc_reserved - Calculate the number of blocks to reserve when
421 * refunding a transaction's unused buffers.
422 * @sdp: The GFS2 superblock
423 *
424 * This is complex. We need to reserve room for all our currently used
425 * metadata buffers (e.g. normal file I/O rewriting file time stamps) and
426 * all our journaled data buffers for journaled files (e.g. files in the
427 * meta_fs like rindex, or files for which chattr +j was done.)
428 * If we don't reserve enough space, gfs2_log_refund and gfs2_log_flush
429 * will count it as free space (sd_log_blks_free) and corruption will follow.
430 *
431 * We can have metadata bufs and jdata bufs in the same journal. So each
432 * type gets its own log header, for which we need to reserve a block.
433 * In fact, each type has the potential for needing more than one header
434 * in cases where we have more buffers than will fit on a journal page.
435 * Metadata journal entries take up half the space of journaled buffer entries.
436 * Thus, metadata entries have buf_limit (502) and journaled buffers have
437 * databuf_limit (251) before they cause a wrap around.
438 *
439 * Also, we need to reserve blocks for revoke journal entries and one for an
440 * overall header for the lot.
441 *
442 * Returns: the number of blocks reserved
443 */
444static unsigned int calc_reserved(struct gfs2_sbd *sdp)
445{
446 unsigned int reserved = 0;
447 unsigned int mbuf;
448 unsigned int dbuf;
449 struct gfs2_trans *tr = sdp->sd_log_tr;
450
451 if (tr) {
452 mbuf = tr->tr_num_buf_new - tr->tr_num_buf_rm;
453 dbuf = tr->tr_num_databuf_new - tr->tr_num_databuf_rm;
454 reserved = mbuf + dbuf;
455 /* Account for header blocks */
456 reserved += DIV_ROUND_UP(mbuf, buf_limit(sdp));
457 reserved += DIV_ROUND_UP(dbuf, databuf_limit(sdp));
458 }
459
460 if (sdp->sd_log_commited_revoke > 0)
461 reserved += gfs2_struct2blk(sdp, sdp->sd_log_commited_revoke,
462 sizeof(u64));
463 /* One for the overall header */
464 if (reserved)
465 reserved++;
466 return reserved;
467}
468
469static unsigned int current_tail(struct gfs2_sbd *sdp)
470{
471 struct gfs2_trans *tr;
472 unsigned int tail;
473
474 spin_lock(&sdp->sd_ail_lock);
475
476 if (list_empty(&sdp->sd_ail1_list)) {
477 tail = sdp->sd_log_head;
478 } else {
479 tr = list_entry(sdp->sd_ail1_list.prev, struct gfs2_trans,
480 tr_list);
481 tail = tr->tr_first;
482 }
483
484 spin_unlock(&sdp->sd_ail_lock);
485
486 return tail;
487}
488
489static void log_pull_tail(struct gfs2_sbd *sdp, unsigned int new_tail)
490{
491 unsigned int dist = log_distance(sdp, new_tail, sdp->sd_log_tail);
492
493 ail2_empty(sdp, new_tail);
494
495 atomic_add(dist, &sdp->sd_log_blks_free);
496 trace_gfs2_log_blocks(sdp, dist);
497 gfs2_assert_withdraw(sdp, atomic_read(&sdp->sd_log_blks_free) <=
498 sdp->sd_jdesc->jd_blocks);
499
500 sdp->sd_log_tail = new_tail;
501}
502
503
504static void log_flush_wait(struct gfs2_sbd *sdp)
505{
506 DEFINE_WAIT(wait);
507
508 if (atomic_read(&sdp->sd_log_in_flight)) {
509 do {
510 prepare_to_wait(&sdp->sd_log_flush_wait, &wait,
511 TASK_UNINTERRUPTIBLE);
512 if (atomic_read(&sdp->sd_log_in_flight))
513 io_schedule();
514 } while(atomic_read(&sdp->sd_log_in_flight));
515 finish_wait(&sdp->sd_log_flush_wait, &wait);
516 }
517}
518
519static int ip_cmp(void *priv, struct list_head *a, struct list_head *b)
520{
521 struct gfs2_inode *ipa, *ipb;
522
523 ipa = list_entry(a, struct gfs2_inode, i_ordered);
524 ipb = list_entry(b, struct gfs2_inode, i_ordered);
525
526 if (ipa->i_no_addr < ipb->i_no_addr)
527 return -1;
528 if (ipa->i_no_addr > ipb->i_no_addr)
529 return 1;
530 return 0;
531}
532
533static void gfs2_ordered_write(struct gfs2_sbd *sdp)
534{
535 struct gfs2_inode *ip;
536 LIST_HEAD(written);
537
538 spin_lock(&sdp->sd_ordered_lock);
539 list_sort(NULL, &sdp->sd_log_le_ordered, &ip_cmp);
540 while (!list_empty(&sdp->sd_log_le_ordered)) {
541 ip = list_entry(sdp->sd_log_le_ordered.next, struct gfs2_inode, i_ordered);
542 if (ip->i_inode.i_mapping->nrpages == 0) {
543 test_and_clear_bit(GIF_ORDERED, &ip->i_flags);
544 list_del(&ip->i_ordered);
545 continue;
546 }
547 list_move(&ip->i_ordered, &written);
548 spin_unlock(&sdp->sd_ordered_lock);
549 filemap_fdatawrite(ip->i_inode.i_mapping);
550 spin_lock(&sdp->sd_ordered_lock);
551 }
552 list_splice(&written, &sdp->sd_log_le_ordered);
553 spin_unlock(&sdp->sd_ordered_lock);
554}
555
556static void gfs2_ordered_wait(struct gfs2_sbd *sdp)
557{
558 struct gfs2_inode *ip;
559
560 spin_lock(&sdp->sd_ordered_lock);
561 while (!list_empty(&sdp->sd_log_le_ordered)) {
562 ip = list_entry(sdp->sd_log_le_ordered.next, struct gfs2_inode, i_ordered);
563 list_del(&ip->i_ordered);
564 WARN_ON(!test_and_clear_bit(GIF_ORDERED, &ip->i_flags));
565 if (ip->i_inode.i_mapping->nrpages == 0)
566 continue;
567 spin_unlock(&sdp->sd_ordered_lock);
568 filemap_fdatawait(ip->i_inode.i_mapping);
569 spin_lock(&sdp->sd_ordered_lock);
570 }
571 spin_unlock(&sdp->sd_ordered_lock);
572}
573
574void gfs2_ordered_del_inode(struct gfs2_inode *ip)
575{
576 struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
577
578 spin_lock(&sdp->sd_ordered_lock);
579 if (test_and_clear_bit(GIF_ORDERED, &ip->i_flags))
580 list_del(&ip->i_ordered);
581 spin_unlock(&sdp->sd_ordered_lock);
582}
583
584void gfs2_add_revoke(struct gfs2_sbd *sdp, struct gfs2_bufdata *bd)
585{
586 struct buffer_head *bh = bd->bd_bh;
587 struct gfs2_glock *gl = bd->bd_gl;
588
589 bh->b_private = NULL;
590 bd->bd_blkno = bh->b_blocknr;
591 gfs2_remove_from_ail(bd); /* drops ref on bh */
592 bd->bd_bh = NULL;
593 bd->bd_ops = &gfs2_revoke_lops;
594 sdp->sd_log_num_revoke++;
595 atomic_inc(&gl->gl_revokes);
596 set_bit(GLF_LFLUSH, &gl->gl_flags);
597 list_add(&bd->bd_list, &sdp->sd_log_le_revoke);
598}
599
600void gfs2_write_revokes(struct gfs2_sbd *sdp)
601{
602 struct gfs2_trans *tr;
603 struct gfs2_bufdata *bd, *tmp;
604 int have_revokes = 0;
605 int max_revokes = (sdp->sd_sb.sb_bsize - sizeof(struct gfs2_log_descriptor)) / sizeof(u64);
606
607 gfs2_ail1_empty(sdp);
608 spin_lock(&sdp->sd_ail_lock);
609 list_for_each_entry(tr, &sdp->sd_ail1_list, tr_list) {
610 list_for_each_entry(bd, &tr->tr_ail2_list, bd_ail_st_list) {
611 if (list_empty(&bd->bd_list)) {
612 have_revokes = 1;
613 goto done;
614 }
615 }
616 }
617done:
618 spin_unlock(&sdp->sd_ail_lock);
619 if (have_revokes == 0)
620 return;
621 while (sdp->sd_log_num_revoke > max_revokes)
622 max_revokes += (sdp->sd_sb.sb_bsize - sizeof(struct gfs2_meta_header)) / sizeof(u64);
623 max_revokes -= sdp->sd_log_num_revoke;
624 if (!sdp->sd_log_num_revoke) {
625 atomic_dec(&sdp->sd_log_blks_free);
626 /* If no blocks have been reserved, we need to also
627 * reserve a block for the header */
628 if (!sdp->sd_log_blks_reserved)
629 atomic_dec(&sdp->sd_log_blks_free);
630 }
631 gfs2_log_lock(sdp);
632 spin_lock(&sdp->sd_ail_lock);
633 list_for_each_entry(tr, &sdp->sd_ail1_list, tr_list) {
634 list_for_each_entry_safe(bd, tmp, &tr->tr_ail2_list, bd_ail_st_list) {
635 if (max_revokes == 0)
636 goto out_of_blocks;
637 if (!list_empty(&bd->bd_list))
638 continue;
639 gfs2_add_revoke(sdp, bd);
640 max_revokes--;
641 }
642 }
643out_of_blocks:
644 spin_unlock(&sdp->sd_ail_lock);
645 gfs2_log_unlock(sdp);
646
647 if (!sdp->sd_log_num_revoke) {
648 atomic_inc(&sdp->sd_log_blks_free);
649 if (!sdp->sd_log_blks_reserved)
650 atomic_inc(&sdp->sd_log_blks_free);
651 }
652}
653
654/**
655 * write_log_header - Write a journal log header buffer at sd_log_flush_head
656 * @sdp: The GFS2 superblock
657 * @jd: journal descriptor of the journal to which we are writing
658 * @seq: sequence number
659 * @tail: tail of the log
660 * @flags: log header flags GFS2_LOG_HEAD_*
661 * @op_flags: flags to pass to the bio
662 *
663 * Returns: the initialized log buffer descriptor
664 */
665
666void gfs2_write_log_header(struct gfs2_sbd *sdp, struct gfs2_jdesc *jd,
667 u64 seq, u32 tail, u32 flags, int op_flags)
668{
669 struct gfs2_log_header *lh;
670 u32 hash, crc;
671 struct page *page = mempool_alloc(gfs2_page_pool, GFP_NOIO);
672 struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
673 struct timespec64 tv;
674 struct super_block *sb = sdp->sd_vfs;
675 u64 addr;
676
677 lh = page_address(page);
678 clear_page(lh);
679
680 lh->lh_header.mh_magic = cpu_to_be32(GFS2_MAGIC);
681 lh->lh_header.mh_type = cpu_to_be32(GFS2_METATYPE_LH);
682 lh->lh_header.__pad0 = cpu_to_be64(0);
683 lh->lh_header.mh_format = cpu_to_be32(GFS2_FORMAT_LH);
684 lh->lh_header.mh_jid = cpu_to_be32(sdp->sd_jdesc->jd_jid);
685 lh->lh_sequence = cpu_to_be64(seq);
686 lh->lh_flags = cpu_to_be32(flags);
687 lh->lh_tail = cpu_to_be32(tail);
688 lh->lh_blkno = cpu_to_be32(sdp->sd_log_flush_head);
689 hash = ~crc32(~0, lh, LH_V1_SIZE);
690 lh->lh_hash = cpu_to_be32(hash);
691
692 tv = current_kernel_time64();
693 lh->lh_nsec = cpu_to_be32(tv.tv_nsec);
694 lh->lh_sec = cpu_to_be64(tv.tv_sec);
695 addr = gfs2_log_bmap(sdp);
696 lh->lh_addr = cpu_to_be64(addr);
697 lh->lh_jinode = cpu_to_be64(GFS2_I(jd->jd_inode)->i_no_addr);
698
699 /* We may only write local statfs, quota, etc., when writing to our
700 own journal. The values are left 0 when recovering a journal
701 different from our own. */
702 if (!(flags & GFS2_LOG_HEAD_RECOVERY)) {
703 lh->lh_statfs_addr =
704 cpu_to_be64(GFS2_I(sdp->sd_sc_inode)->i_no_addr);
705 lh->lh_quota_addr =
706 cpu_to_be64(GFS2_I(sdp->sd_qc_inode)->i_no_addr);
707
708 spin_lock(&sdp->sd_statfs_spin);
709 lh->lh_local_total = cpu_to_be64(l_sc->sc_total);
710 lh->lh_local_free = cpu_to_be64(l_sc->sc_free);
711 lh->lh_local_dinodes = cpu_to_be64(l_sc->sc_dinodes);
712 spin_unlock(&sdp->sd_statfs_spin);
713 }
714
715 BUILD_BUG_ON(offsetof(struct gfs2_log_header, lh_crc) != LH_V1_SIZE);
716
717 crc = crc32c(~0, (void *)lh + LH_V1_SIZE + 4,
718 sb->s_blocksize - LH_V1_SIZE - 4);
719 lh->lh_crc = cpu_to_be32(crc);
720
721 gfs2_log_write(sdp, page, sb->s_blocksize, 0, addr);
722 gfs2_log_flush_bio(sdp, REQ_OP_WRITE, op_flags);
723 log_flush_wait(sdp);
724}
725
726/**
727 * log_write_header - Get and initialize a journal header buffer
728 * @sdp: The GFS2 superblock
729 * @flags: The log header flags, including log header origin
730 *
731 * Returns: the initialized log buffer descriptor
732 */
733
734static void log_write_header(struct gfs2_sbd *sdp, u32 flags)
735{
736 unsigned int tail;
737 int op_flags = REQ_PREFLUSH | REQ_FUA | REQ_META | REQ_SYNC;
738 enum gfs2_freeze_state state = atomic_read(&sdp->sd_freeze_state);
739
740 gfs2_assert_withdraw(sdp, (state != SFS_FROZEN));
741 tail = current_tail(sdp);
742
743 if (test_bit(SDF_NOBARRIERS, &sdp->sd_flags)) {
744 gfs2_ordered_wait(sdp);
745 log_flush_wait(sdp);
746 op_flags = REQ_SYNC | REQ_META | REQ_PRIO;
747 }
748 sdp->sd_log_idle = (tail == sdp->sd_log_flush_head);
749 gfs2_write_log_header(sdp, sdp->sd_jdesc, sdp->sd_log_sequence++, tail,
750 flags, op_flags);
751
752 if (sdp->sd_log_tail != tail)
753 log_pull_tail(sdp, tail);
754}
755
756/**
757 * gfs2_log_flush - flush incore transaction(s)
758 * @sdp: the filesystem
759 * @gl: The glock structure to flush. If NULL, flush the whole incore log
760 * @flags: The log header flags: GFS2_LOG_HEAD_FLUSH_* and debug flags
761 *
762 */
763
764void gfs2_log_flush(struct gfs2_sbd *sdp, struct gfs2_glock *gl, u32 flags)
765{
766 struct gfs2_trans *tr;
767 enum gfs2_freeze_state state = atomic_read(&sdp->sd_freeze_state);
768
769 down_write(&sdp->sd_log_flush_lock);
770
771 /* Log might have been flushed while we waited for the flush lock */
772 if (gl && !test_bit(GLF_LFLUSH, &gl->gl_flags)) {
773 up_write(&sdp->sd_log_flush_lock);
774 return;
775 }
776 trace_gfs2_log_flush(sdp, 1, flags);
777
778 if (flags & GFS2_LOG_HEAD_FLUSH_SHUTDOWN)
779 clear_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags);
780
781 sdp->sd_log_flush_head = sdp->sd_log_head;
782 tr = sdp->sd_log_tr;
783 if (tr) {
784 sdp->sd_log_tr = NULL;
785 INIT_LIST_HEAD(&tr->tr_ail1_list);
786 INIT_LIST_HEAD(&tr->tr_ail2_list);
787 tr->tr_first = sdp->sd_log_flush_head;
788 if (unlikely (state == SFS_FROZEN))
789 gfs2_assert_withdraw(sdp, !tr->tr_num_buf_new && !tr->tr_num_databuf_new);
790 }
791
792 if (unlikely(state == SFS_FROZEN))
793 gfs2_assert_withdraw(sdp, !sdp->sd_log_num_revoke);
794 gfs2_assert_withdraw(sdp,
795 sdp->sd_log_num_revoke == sdp->sd_log_commited_revoke);
796
797 gfs2_ordered_write(sdp);
798 lops_before_commit(sdp, tr);
799 gfs2_log_flush_bio(sdp, REQ_OP_WRITE, 0);
800
801 if (sdp->sd_log_head != sdp->sd_log_flush_head) {
802 log_flush_wait(sdp);
803 log_write_header(sdp, flags);
804 } else if (sdp->sd_log_tail != current_tail(sdp) && !sdp->sd_log_idle){
805 atomic_dec(&sdp->sd_log_blks_free); /* Adjust for unreserved buffer */
806 trace_gfs2_log_blocks(sdp, -1);
807 log_write_header(sdp, flags);
808 }
809 lops_after_commit(sdp, tr);
810
811 gfs2_log_lock(sdp);
812 sdp->sd_log_head = sdp->sd_log_flush_head;
813 sdp->sd_log_blks_reserved = 0;
814 sdp->sd_log_commited_revoke = 0;
815
816 spin_lock(&sdp->sd_ail_lock);
817 if (tr && !list_empty(&tr->tr_ail1_list)) {
818 list_add(&tr->tr_list, &sdp->sd_ail1_list);
819 tr = NULL;
820 }
821 spin_unlock(&sdp->sd_ail_lock);
822 gfs2_log_unlock(sdp);
823
824 if (!(flags & GFS2_LOG_HEAD_FLUSH_NORMAL)) {
825 if (!sdp->sd_log_idle) {
826 for (;;) {
827 gfs2_ail1_start(sdp);
828 gfs2_ail1_wait(sdp);
829 if (gfs2_ail1_empty(sdp))
830 break;
831 }
832 atomic_dec(&sdp->sd_log_blks_free); /* Adjust for unreserved buffer */
833 trace_gfs2_log_blocks(sdp, -1);
834 log_write_header(sdp, flags);
835 sdp->sd_log_head = sdp->sd_log_flush_head;
836 }
837 if (flags & (GFS2_LOG_HEAD_FLUSH_SHUTDOWN |
838 GFS2_LOG_HEAD_FLUSH_FREEZE))
839 gfs2_log_shutdown(sdp);
840 if (flags & GFS2_LOG_HEAD_FLUSH_FREEZE)
841 atomic_set(&sdp->sd_freeze_state, SFS_FROZEN);
842 }
843
844 trace_gfs2_log_flush(sdp, 0, flags);
845 up_write(&sdp->sd_log_flush_lock);
846
847 kfree(tr);
848}
849
850/**
851 * gfs2_merge_trans - Merge a new transaction into a cached transaction
852 * @old: Original transaction to be expanded
853 * @new: New transaction to be merged
854 */
855
856static void gfs2_merge_trans(struct gfs2_trans *old, struct gfs2_trans *new)
857{
858 WARN_ON_ONCE(!test_bit(TR_ATTACHED, &old->tr_flags));
859
860 old->tr_num_buf_new += new->tr_num_buf_new;
861 old->tr_num_databuf_new += new->tr_num_databuf_new;
862 old->tr_num_buf_rm += new->tr_num_buf_rm;
863 old->tr_num_databuf_rm += new->tr_num_databuf_rm;
864 old->tr_num_revoke += new->tr_num_revoke;
865 old->tr_num_revoke_rm += new->tr_num_revoke_rm;
866
867 list_splice_tail_init(&new->tr_databuf, &old->tr_databuf);
868 list_splice_tail_init(&new->tr_buf, &old->tr_buf);
869}
870
871static void log_refund(struct gfs2_sbd *sdp, struct gfs2_trans *tr)
872{
873 unsigned int reserved;
874 unsigned int unused;
875 unsigned int maxres;
876
877 gfs2_log_lock(sdp);
878
879 if (sdp->sd_log_tr) {
880 gfs2_merge_trans(sdp->sd_log_tr, tr);
881 } else if (tr->tr_num_buf_new || tr->tr_num_databuf_new) {
882 gfs2_assert_withdraw(sdp, test_bit(TR_ALLOCED, &tr->tr_flags));
883 sdp->sd_log_tr = tr;
884 set_bit(TR_ATTACHED, &tr->tr_flags);
885 }
886
887 sdp->sd_log_commited_revoke += tr->tr_num_revoke - tr->tr_num_revoke_rm;
888 reserved = calc_reserved(sdp);
889 maxres = sdp->sd_log_blks_reserved + tr->tr_reserved;
890 gfs2_assert_withdraw(sdp, maxres >= reserved);
891 unused = maxres - reserved;
892 atomic_add(unused, &sdp->sd_log_blks_free);
893 trace_gfs2_log_blocks(sdp, unused);
894 gfs2_assert_withdraw(sdp, atomic_read(&sdp->sd_log_blks_free) <=
895 sdp->sd_jdesc->jd_blocks);
896 sdp->sd_log_blks_reserved = reserved;
897
898 gfs2_log_unlock(sdp);
899}
900
901/**
902 * gfs2_log_commit - Commit a transaction to the log
903 * @sdp: the filesystem
904 * @tr: the transaction
905 *
906 * We wake up gfs2_logd if the number of pinned blocks exceed thresh1
907 * or the total number of used blocks (pinned blocks plus AIL blocks)
908 * is greater than thresh2.
909 *
910 * At mount time thresh1 is 1/3rd of journal size, thresh2 is 2/3rd of
911 * journal size.
912 *
913 * Returns: errno
914 */
915
916void gfs2_log_commit(struct gfs2_sbd *sdp, struct gfs2_trans *tr)
917{
918 log_refund(sdp, tr);
919
920 if (atomic_read(&sdp->sd_log_pinned) > atomic_read(&sdp->sd_log_thresh1) ||
921 ((sdp->sd_jdesc->jd_blocks - atomic_read(&sdp->sd_log_blks_free)) >
922 atomic_read(&sdp->sd_log_thresh2)))
923 wake_up(&sdp->sd_logd_waitq);
924}
925
926/**
927 * gfs2_log_shutdown - write a shutdown header into a journal
928 * @sdp: the filesystem
929 *
930 */
931
932void gfs2_log_shutdown(struct gfs2_sbd *sdp)
933{
934 gfs2_assert_withdraw(sdp, !sdp->sd_log_blks_reserved);
935 gfs2_assert_withdraw(sdp, !sdp->sd_log_num_revoke);
936 gfs2_assert_withdraw(sdp, list_empty(&sdp->sd_ail1_list));
937
938 sdp->sd_log_flush_head = sdp->sd_log_head;
939
940 log_write_header(sdp, GFS2_LOG_HEAD_UNMOUNT | GFS2_LFC_SHUTDOWN);
941
942 gfs2_assert_warn(sdp, sdp->sd_log_head == sdp->sd_log_tail);
943 gfs2_assert_warn(sdp, list_empty(&sdp->sd_ail2_list));
944
945 sdp->sd_log_head = sdp->sd_log_flush_head;
946 sdp->sd_log_tail = sdp->sd_log_head;
947}
948
949static inline int gfs2_jrnl_flush_reqd(struct gfs2_sbd *sdp)
950{
951 return (atomic_read(&sdp->sd_log_pinned) +
952 atomic_read(&sdp->sd_log_blks_needed) >=
953 atomic_read(&sdp->sd_log_thresh1));
954}
955
956static inline int gfs2_ail_flush_reqd(struct gfs2_sbd *sdp)
957{
958 unsigned int used_blocks = sdp->sd_jdesc->jd_blocks - atomic_read(&sdp->sd_log_blks_free);
959
960 if (test_and_clear_bit(SDF_FORCE_AIL_FLUSH, &sdp->sd_flags))
961 return 1;
962
963 return used_blocks + atomic_read(&sdp->sd_log_blks_needed) >=
964 atomic_read(&sdp->sd_log_thresh2);
965}
966
967/**
968 * gfs2_logd - Update log tail as Active Items get flushed to in-place blocks
969 * @sdp: Pointer to GFS2 superblock
970 *
971 * Also, periodically check to make sure that we're using the most recent
972 * journal index.
973 */
974
975int gfs2_logd(void *data)
976{
977 struct gfs2_sbd *sdp = data;
978 unsigned long t = 1;
979 DEFINE_WAIT(wait);
980 bool did_flush;
981
982 while (!kthread_should_stop()) {
983
984 /* Check for errors writing to the journal */
985 if (sdp->sd_log_error) {
986 gfs2_lm_withdraw(sdp,
987 "GFS2: fsid=%s: error %d: "
988 "withdrawing the file system to "
989 "prevent further damage.\n",
990 sdp->sd_fsname, sdp->sd_log_error);
991 }
992
993 did_flush = false;
994 if (gfs2_jrnl_flush_reqd(sdp) || t == 0) {
995 gfs2_ail1_empty(sdp);
996 gfs2_log_flush(sdp, NULL, GFS2_LOG_HEAD_FLUSH_NORMAL |
997 GFS2_LFC_LOGD_JFLUSH_REQD);
998 did_flush = true;
999 }
1000
1001 if (gfs2_ail_flush_reqd(sdp)) {
1002 gfs2_ail1_start(sdp);
1003 gfs2_ail1_wait(sdp);
1004 gfs2_ail1_empty(sdp);
1005 gfs2_log_flush(sdp, NULL, GFS2_LOG_HEAD_FLUSH_NORMAL |
1006 GFS2_LFC_LOGD_AIL_FLUSH_REQD);
1007 did_flush = true;
1008 }
1009
1010 if (!gfs2_ail_flush_reqd(sdp) || did_flush)
1011 wake_up(&sdp->sd_log_waitq);
1012
1013 t = gfs2_tune_get(sdp, gt_logd_secs) * HZ;
1014
1015 try_to_freeze();
1016
1017 do {
1018 prepare_to_wait(&sdp->sd_logd_waitq, &wait,
1019 TASK_INTERRUPTIBLE);
1020 if (!gfs2_ail_flush_reqd(sdp) &&
1021 !gfs2_jrnl_flush_reqd(sdp) &&
1022 !kthread_should_stop())
1023 t = schedule_timeout(t);
1024 } while(t && !gfs2_ail_flush_reqd(sdp) &&
1025 !gfs2_jrnl_flush_reqd(sdp) &&
1026 !kthread_should_stop());
1027 finish_wait(&sdp->sd_logd_waitq, &wait);
1028 }
1029
1030 return 0;
1031}
1032