2 * Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
3 * Copyright (C) 2004-2005 Red Hat, Inc. All rights reserved.
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 v.2.
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 <asm/semaphore.h>
19 #include "lm_interface.h"
30 static void do_lock_wait(struct gfs2_sbd *sdp, wait_queue_head_t *wq,
33 wait_event(*wq, atomic_read(a) ? 0 : 1);
36 static void lock_for_trans(struct gfs2_sbd *sdp)
38 do_lock_wait(sdp, &sdp->sd_log_trans_wq, &sdp->sd_log_flush_count);
39 atomic_inc(&sdp->sd_log_trans_count);
42 static void unlock_from_trans(struct gfs2_sbd *sdp)
44 gfs2_assert_warn(sdp, atomic_read(&sdp->sd_log_trans_count));
45 if (atomic_dec_and_test(&sdp->sd_log_trans_count))
46 wake_up(&sdp->sd_log_flush_wq);
49 static void gfs2_lock_for_flush(struct gfs2_sbd *sdp)
51 atomic_inc(&sdp->sd_log_flush_count);
52 do_lock_wait(sdp, &sdp->sd_log_flush_wq, &sdp->sd_log_trans_count);
55 static void gfs2_unlock_from_flush(struct gfs2_sbd *sdp)
57 gfs2_assert_warn(sdp, atomic_read(&sdp->sd_log_flush_count));
58 if (atomic_dec_and_test(&sdp->sd_log_flush_count))
59 wake_up(&sdp->sd_log_trans_wq);
63 * gfs2_struct2blk - compute stuff
64 * @sdp: the filesystem
65 * @nstruct: the number of structures
66 * @ssize: the size of the structures
68 * Compute the number of log descriptor blocks needed to hold a certain number
69 * of structures of a certain size.
71 * Returns: the number of blocks needed (minimum is always 1)
74 unsigned int gfs2_struct2blk(struct gfs2_sbd *sdp, unsigned int nstruct,
78 unsigned int first, second;
81 first = (sdp->sd_sb.sb_bsize - sizeof(struct gfs2_log_descriptor)) /
84 if (nstruct > first) {
85 second = (sdp->sd_sb.sb_bsize -
86 sizeof(struct gfs2_meta_header)) / ssize;
87 blks += DIV_ROUND_UP(nstruct - first, second);
93 void gfs2_ail1_start(struct gfs2_sbd *sdp, int flags)
95 struct list_head *head = &sdp->sd_ail1_list;
97 struct list_head *first, *tmp;
98 struct gfs2_ail *first_ai, *ai;
101 if (list_empty(head)) {
102 gfs2_log_unlock(sdp);
105 sync_gen = sdp->sd_ail_sync_gen++;
108 first_ai = list_entry(first, struct gfs2_ail, ai_list);
109 first_ai->ai_sync_gen = sync_gen;
110 gfs2_ail1_start_one(sdp, first_ai);
117 (head->prev != first ||
118 gfs2_ail1_empty_one(sdp, first_ai, 0)))
121 for (tmp = head->prev; tmp != head; tmp = tmp->prev) {
122 ai = list_entry(tmp, struct gfs2_ail, ai_list);
123 if (ai->ai_sync_gen >= sync_gen)
125 ai->ai_sync_gen = sync_gen;
126 gfs2_ail1_start_one(sdp, ai);
134 gfs2_log_unlock(sdp);
137 int gfs2_ail1_empty(struct gfs2_sbd *sdp, int flags)
139 struct gfs2_ail *ai, *s;
144 list_for_each_entry_safe_reverse(ai, s, &sdp->sd_ail1_list, ai_list) {
145 if (gfs2_ail1_empty_one(sdp, ai, flags))
146 list_move(&ai->ai_list, &sdp->sd_ail2_list);
147 else if (!(flags & DIO_ALL))
151 ret = list_empty(&sdp->sd_ail1_list);
153 gfs2_log_unlock(sdp);
158 static void ail2_empty(struct gfs2_sbd *sdp, unsigned int new_tail)
160 struct gfs2_ail *ai, *safe;
161 unsigned int old_tail = sdp->sd_log_tail;
162 int wrap = (new_tail < old_tail);
167 list_for_each_entry_safe(ai, safe, &sdp->sd_ail2_list, ai_list) {
168 a = (old_tail <= ai->ai_first);
169 b = (ai->ai_first < new_tail);
170 rm = (wrap) ? (a || b) : (a && b);
174 gfs2_ail2_empty_one(sdp, ai);
175 list_del(&ai->ai_list);
176 gfs2_assert_warn(sdp, list_empty(&ai->ai_ail1_list));
177 gfs2_assert_warn(sdp, list_empty(&ai->ai_ail2_list));
181 gfs2_log_unlock(sdp);
185 * gfs2_log_reserve - Make a log reservation
186 * @sdp: The GFS2 superblock
187 * @blks: The number of blocks to reserve
192 int gfs2_log_reserve(struct gfs2_sbd *sdp, unsigned int blks)
195 unsigned int try = 0;
197 if (gfs2_assert_warn(sdp, blks) ||
198 gfs2_assert_warn(sdp, blks <= sdp->sd_jdesc->jd_blocks))
203 if (list_empty(&list)) {
204 list_add_tail(&list, &sdp->sd_log_blks_list);
205 while (sdp->sd_log_blks_list.next != &list) {
206 DECLARE_WAITQUEUE(__wait_chan, current);
207 set_current_state(TASK_UNINTERRUPTIBLE);
208 add_wait_queue(&sdp->sd_log_blks_wait,
210 gfs2_log_unlock(sdp);
213 remove_wait_queue(&sdp->sd_log_blks_wait,
215 set_current_state(TASK_RUNNING);
218 /* Never give away the last block so we can
219 always pull the tail if we need to. */
220 if (sdp->sd_log_blks_free > blks) {
221 sdp->sd_log_blks_free -= blks;
223 gfs2_log_unlock(sdp);
224 wake_up(&sdp->sd_log_blks_wait);
228 gfs2_log_unlock(sdp);
229 gfs2_ail1_empty(sdp, 0);
233 gfs2_ail1_start(sdp, 0);
241 * gfs2_log_release - Release a given number of log blocks
242 * @sdp: The GFS2 superblock
243 * @blks: The number of blocks
247 void gfs2_log_release(struct gfs2_sbd *sdp, unsigned int blks)
249 unlock_from_trans(sdp);
252 sdp->sd_log_blks_free += blks;
253 gfs2_assert_withdraw(sdp,
254 sdp->sd_log_blks_free <= sdp->sd_jdesc->jd_blocks);
255 gfs2_log_unlock(sdp);
258 static uint64_t log_bmap(struct gfs2_sbd *sdp, unsigned int lbn)
264 error = gfs2_block_map(sdp->sd_jdesc->jd_inode->u.generic_ip,
265 lbn, &new, &dbn, NULL);
266 gfs2_assert_withdraw(sdp, !error && dbn);
272 * log_distance - Compute distance between two journal blocks
273 * @sdp: The GFS2 superblock
274 * @newer: The most recent journal block of the pair
275 * @older: The older journal block of the pair
277 * Compute the distance (in the journal direction) between two
278 * blocks in the journal
280 * Returns: the distance in blocks
283 static inline unsigned int log_distance(struct gfs2_sbd *sdp,
289 dist = newer - older;
291 dist += sdp->sd_jdesc->jd_blocks;
296 static unsigned int current_tail(struct gfs2_sbd *sdp)
303 if (list_empty(&sdp->sd_ail1_list))
304 tail = sdp->sd_log_head;
306 ai = list_entry(sdp->sd_ail1_list.prev,
307 struct gfs2_ail, ai_list);
311 gfs2_log_unlock(sdp);
316 static inline void log_incr_head(struct gfs2_sbd *sdp)
318 if (sdp->sd_log_flush_head == sdp->sd_log_tail)
319 gfs2_assert_withdraw(sdp,
320 sdp->sd_log_flush_head == sdp->sd_log_head);
322 if (++sdp->sd_log_flush_head == sdp->sd_jdesc->jd_blocks) {
323 sdp->sd_log_flush_head = 0;
324 sdp->sd_log_flush_wrapped = 1;
329 * gfs2_log_get_buf - Get and initialize a buffer to use for log control data
330 * @sdp: The GFS2 superblock
332 * Returns: the buffer_head
335 struct buffer_head *gfs2_log_get_buf(struct gfs2_sbd *sdp)
337 uint64_t blkno = log_bmap(sdp, sdp->sd_log_flush_head);
338 struct gfs2_log_buf *lb;
339 struct buffer_head *bh;
341 lb = kzalloc(sizeof(struct gfs2_log_buf), GFP_NOFS | __GFP_NOFAIL);
342 list_add(&lb->lb_list, &sdp->sd_log_flush_list);
344 bh = lb->lb_bh = sb_getblk(sdp->sd_vfs, blkno);
346 memset(bh->b_data, 0, bh->b_size);
347 set_buffer_uptodate(bh);
348 clear_buffer_dirty(bh);
357 * gfs2_log_fake_buf - Build a fake buffer head to write metadata buffer to log
358 * @sdp: the filesystem
359 * @data: the data the buffer_head should point to
361 * Returns: the log buffer descriptor
364 struct buffer_head *gfs2_log_fake_buf(struct gfs2_sbd *sdp,
365 struct buffer_head *real)
367 uint64_t blkno = log_bmap(sdp, sdp->sd_log_flush_head);
368 struct gfs2_log_buf *lb;
369 struct buffer_head *bh;
371 lb = kzalloc(sizeof(struct gfs2_log_buf), GFP_NOFS | __GFP_NOFAIL);
372 list_add(&lb->lb_list, &sdp->sd_log_flush_list);
375 bh = lb->lb_bh = alloc_buffer_head(GFP_NOFS | __GFP_NOFAIL);
376 atomic_set(&bh->b_count, 1);
377 bh->b_state = (1 << BH_Mapped) | (1 << BH_Uptodate);
378 set_bh_page(bh, real->b_page, bh_offset(real));
379 bh->b_blocknr = blkno;
380 bh->b_size = sdp->sd_sb.sb_bsize;
381 bh->b_bdev = sdp->sd_vfs->s_bdev;
388 static void log_pull_tail(struct gfs2_sbd *sdp, unsigned int new_tail, int pull)
390 unsigned int dist = log_distance(sdp, new_tail, sdp->sd_log_tail);
392 ail2_empty(sdp, new_tail);
395 sdp->sd_log_blks_free += dist - ((pull) ? 1 : 0);
396 gfs2_assert_withdraw(sdp,
397 sdp->sd_log_blks_free <= sdp->sd_jdesc->jd_blocks);
398 gfs2_log_unlock(sdp);
400 sdp->sd_log_tail = new_tail;
404 * log_write_header - Get and initialize a journal header buffer
405 * @sdp: The GFS2 superblock
407 * Returns: the initialized log buffer descriptor
410 static void log_write_header(struct gfs2_sbd *sdp, uint32_t flags, int pull)
412 uint64_t blkno = log_bmap(sdp, sdp->sd_log_flush_head);
413 struct buffer_head *bh;
414 struct gfs2_log_header *lh;
418 bh = sb_getblk(sdp->sd_vfs, blkno);
420 memset(bh->b_data, 0, bh->b_size);
421 set_buffer_uptodate(bh);
422 clear_buffer_dirty(bh);
425 gfs2_ail1_empty(sdp, 0);
426 tail = current_tail(sdp);
428 lh = (struct gfs2_log_header *)bh->b_data;
429 memset(lh, 0, sizeof(struct gfs2_log_header));
430 lh->lh_header.mh_magic = cpu_to_be32(GFS2_MAGIC);
431 lh->lh_header.mh_type = cpu_to_be16(GFS2_METATYPE_LH);
432 lh->lh_header.mh_format = cpu_to_be16(GFS2_FORMAT_LH);
433 lh->lh_sequence = be64_to_cpu(sdp->sd_log_sequence++);
434 lh->lh_flags = be32_to_cpu(flags);
435 lh->lh_tail = be32_to_cpu(tail);
436 lh->lh_blkno = be32_to_cpu(sdp->sd_log_flush_head);
437 hash = gfs2_disk_hash(bh->b_data, sizeof(struct gfs2_log_header));
438 lh->lh_hash = cpu_to_be32(hash);
440 set_buffer_dirty(bh);
441 if (sync_dirty_buffer(bh))
442 gfs2_io_error_bh(sdp, bh);
445 if (sdp->sd_log_tail != tail)
446 log_pull_tail(sdp, tail, pull);
448 gfs2_assert_withdraw(sdp, !pull);
450 sdp->sd_log_idle = (tail == sdp->sd_log_flush_head);
454 static void log_flush_commit(struct gfs2_sbd *sdp)
456 struct list_head *head = &sdp->sd_log_flush_list;
457 struct gfs2_log_buf *lb;
458 struct buffer_head *bh;
461 d = log_distance(sdp, sdp->sd_log_flush_head, sdp->sd_log_head);
463 gfs2_assert_withdraw(sdp, d + 1 == sdp->sd_log_blks_reserved);
465 while (!list_empty(head)) {
466 lb = list_entry(head->next, struct gfs2_log_buf, lb_list);
467 list_del(&lb->lb_list);
471 if (!buffer_uptodate(bh))
472 gfs2_io_error_bh(sdp, bh);
474 while (atomic_read(&bh->b_count) != 1) /* Grrrr... */
476 free_buffer_head(bh);
482 log_write_header(sdp, 0, 0);
486 * gfs2_log_flush_i - flush incore transaction(s)
487 * @sdp: the filesystem
488 * @gl: The glock structure to flush. If NULL, flush the whole incore log
492 void gfs2_log_flush_i(struct gfs2_sbd *sdp, struct gfs2_glock *gl)
496 ai = kzalloc(sizeof(struct gfs2_ail), GFP_NOFS | __GFP_NOFAIL);
497 INIT_LIST_HEAD(&ai->ai_ail1_list);
498 INIT_LIST_HEAD(&ai->ai_ail2_list);
499 gfs2_lock_for_flush(sdp);
503 if (list_empty(&gl->gl_le.le_list)) {
504 gfs2_log_unlock(sdp);
505 gfs2_unlock_from_flush(sdp);
509 gfs2_log_unlock(sdp);
512 mutex_lock(&sdp->sd_log_flush_lock);
514 gfs2_assert_withdraw(sdp,
515 sdp->sd_log_num_buf == sdp->sd_log_commited_buf);
516 gfs2_assert_withdraw(sdp,
517 sdp->sd_log_num_revoke == sdp->sd_log_commited_revoke);
519 sdp->sd_log_flush_head = sdp->sd_log_head;
520 sdp->sd_log_flush_wrapped = 0;
521 ai->ai_first = sdp->sd_log_flush_head;
523 lops_before_commit(sdp);
524 if (!list_empty(&sdp->sd_log_flush_list))
525 log_flush_commit(sdp);
526 else if (sdp->sd_log_tail != current_tail(sdp) && !sdp->sd_log_idle)
527 log_write_header(sdp, 0, PULL);
528 lops_after_commit(sdp, ai);
529 sdp->sd_log_head = sdp->sd_log_flush_head;
530 if (sdp->sd_log_flush_wrapped)
533 sdp->sd_log_blks_reserved =
534 sdp->sd_log_commited_buf =
535 sdp->sd_log_commited_revoke = 0;
538 if (!list_empty(&ai->ai_ail1_list)) {
539 list_add(&ai->ai_list, &sdp->sd_ail1_list);
542 gfs2_log_unlock(sdp);
544 mutex_unlock(&sdp->sd_log_flush_lock);
545 sdp->sd_vfs->s_dirt = 0;
546 gfs2_unlock_from_flush(sdp);
551 static void log_refund(struct gfs2_sbd *sdp, struct gfs2_trans *tr)
553 unsigned int reserved = 1;
558 sdp->sd_log_commited_buf += tr->tr_num_buf_new - tr->tr_num_buf_rm;
559 gfs2_assert_withdraw(sdp, ((int)sdp->sd_log_commited_buf) >= 0);
560 sdp->sd_log_commited_revoke += tr->tr_num_revoke - tr->tr_num_revoke_rm;
561 gfs2_assert_withdraw(sdp, ((int)sdp->sd_log_commited_revoke) >= 0);
563 if (sdp->sd_log_commited_buf)
564 reserved += 1 + sdp->sd_log_commited_buf +
565 sdp->sd_log_commited_buf/503;
566 if (sdp->sd_log_commited_revoke)
567 reserved += gfs2_struct2blk(sdp, sdp->sd_log_commited_revoke,
570 old = sdp->sd_log_blks_free;
571 sdp->sd_log_blks_free += tr->tr_reserved -
572 (reserved - sdp->sd_log_blks_reserved);
574 gfs2_assert_withdraw(sdp,
575 sdp->sd_log_blks_free >= old);
576 gfs2_assert_withdraw(sdp,
577 sdp->sd_log_blks_free <= sdp->sd_jdesc->jd_blocks);
579 sdp->sd_log_blks_reserved = reserved;
581 gfs2_log_unlock(sdp);
585 * gfs2_log_commit - Commit a transaction to the log
586 * @sdp: the filesystem
587 * @tr: the transaction
592 void gfs2_log_commit(struct gfs2_sbd *sdp, struct gfs2_trans *tr)
595 lops_incore_commit(sdp, tr);
597 sdp->sd_vfs->s_dirt = 1;
598 unlock_from_trans(sdp);
601 if (sdp->sd_log_num_buf > gfs2_tune_get(sdp, gt_incore_log_blocks)) {
602 gfs2_log_unlock(sdp);
605 gfs2_log_unlock(sdp);
609 * gfs2_log_shutdown - write a shutdown header into a journal
610 * @sdp: the filesystem
614 void gfs2_log_shutdown(struct gfs2_sbd *sdp)
616 mutex_lock(&sdp->sd_log_flush_lock);
618 gfs2_assert_withdraw(sdp, !atomic_read(&sdp->sd_log_trans_count));
619 gfs2_assert_withdraw(sdp, !sdp->sd_log_blks_reserved);
620 gfs2_assert_withdraw(sdp, !sdp->sd_log_num_gl);
621 gfs2_assert_withdraw(sdp, !sdp->sd_log_num_buf);
622 gfs2_assert_withdraw(sdp, !sdp->sd_log_num_jdata);
623 gfs2_assert_withdraw(sdp, !sdp->sd_log_num_revoke);
624 gfs2_assert_withdraw(sdp, !sdp->sd_log_num_rg);
625 gfs2_assert_withdraw(sdp, !sdp->sd_log_num_databuf);
626 gfs2_assert_withdraw(sdp, list_empty(&sdp->sd_ail1_list));
628 sdp->sd_log_flush_head = sdp->sd_log_head;
629 sdp->sd_log_flush_wrapped = 0;
631 log_write_header(sdp, GFS2_LOG_HEAD_UNMOUNT, 0);
633 gfs2_assert_withdraw(sdp, sdp->sd_log_blks_free ==
634 sdp->sd_jdesc->jd_blocks);
635 gfs2_assert_withdraw(sdp, sdp->sd_log_head == sdp->sd_log_tail);
636 gfs2_assert_withdraw(sdp, list_empty(&sdp->sd_ail2_list));
638 sdp->sd_log_head = sdp->sd_log_flush_head;
639 if (sdp->sd_log_flush_wrapped)
641 sdp->sd_log_tail = sdp->sd_log_head;
643 mutex_unlock(&sdp->sd_log_flush_lock);