2 * Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
3 * Copyright (C) 2004-2006 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 version 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 <linux/crc32.h>
17 #include <linux/lm_interface.h>
18 #include <linux/delay.h>
33 * gfs2_struct2blk - compute stuff
34 * @sdp: the filesystem
35 * @nstruct: the number of structures
36 * @ssize: the size of the structures
38 * Compute the number of log descriptor blocks needed to hold a certain number
39 * of structures of a certain size.
41 * Returns: the number of blocks needed (minimum is always 1)
44 unsigned int gfs2_struct2blk(struct gfs2_sbd *sdp, unsigned int nstruct,
48 unsigned int first, second;
51 first = (sdp->sd_sb.sb_bsize - sizeof(struct gfs2_log_descriptor)) / ssize;
53 if (nstruct > first) {
54 second = (sdp->sd_sb.sb_bsize -
55 sizeof(struct gfs2_meta_header)) / ssize;
56 blks += DIV_ROUND_UP(nstruct - first, second);
63 * gfs2_ail1_start_one - Start I/O on a part of the AIL
64 * @sdp: the filesystem
65 * @tr: the part of the AIL
69 static void gfs2_ail1_start_one(struct gfs2_sbd *sdp, struct gfs2_ail *ai)
71 struct gfs2_bufdata *bd, *s;
72 struct buffer_head *bh;
75 BUG_ON(!spin_is_locked(&sdp->sd_log_lock));
80 list_for_each_entry_safe_reverse(bd, s, &ai->ai_ail1_list,
84 gfs2_assert(sdp, bd->bd_ail == ai);
86 if (!buffer_busy(bh)) {
87 if (!buffer_uptodate(bh)) {
89 gfs2_io_error_bh(sdp, bh);
92 list_move(&bd->bd_ail_st_list, &ai->ai_ail2_list);
96 if (!buffer_dirty(bh))
99 list_move(&bd->bd_ail_st_list, &ai->ai_ail1_list);
101 gfs2_log_unlock(sdp);
103 ll_rw_block(WRITE, 1, &bh);
113 * gfs2_ail1_empty_one - Check whether or not a trans in the AIL has been synced
114 * @sdp: the filesystem
119 static int gfs2_ail1_empty_one(struct gfs2_sbd *sdp, struct gfs2_ail *ai, int flags)
121 struct gfs2_bufdata *bd, *s;
122 struct buffer_head *bh;
124 list_for_each_entry_safe_reverse(bd, s, &ai->ai_ail1_list,
128 gfs2_assert(sdp, bd->bd_ail == ai);
130 if (buffer_busy(bh)) {
137 if (!buffer_uptodate(bh))
138 gfs2_io_error_bh(sdp, bh);
140 list_move(&bd->bd_ail_st_list, &ai->ai_ail2_list);
143 return list_empty(&ai->ai_ail1_list);
146 static void gfs2_ail1_start(struct gfs2_sbd *sdp, int flags)
148 struct list_head *head = &sdp->sd_ail1_list;
150 struct list_head *first;
151 struct gfs2_ail *first_ai, *ai, *tmp;
155 if (list_empty(head)) {
156 gfs2_log_unlock(sdp);
159 sync_gen = sdp->sd_ail_sync_gen++;
162 first_ai = list_entry(first, struct gfs2_ail, ai_list);
163 first_ai->ai_sync_gen = sync_gen;
164 gfs2_ail1_start_one(sdp, first_ai); /* This may drop log lock */
170 if (first && (head->prev != first ||
171 gfs2_ail1_empty_one(sdp, first_ai, 0)))
175 list_for_each_entry_safe_reverse(ai, tmp, head, ai_list) {
176 if (ai->ai_sync_gen >= sync_gen)
178 ai->ai_sync_gen = sync_gen;
179 gfs2_ail1_start_one(sdp, ai); /* This may drop log lock */
185 gfs2_log_unlock(sdp);
188 int gfs2_ail1_empty(struct gfs2_sbd *sdp, int flags)
190 struct gfs2_ail *ai, *s;
195 list_for_each_entry_safe_reverse(ai, s, &sdp->sd_ail1_list, ai_list) {
196 if (gfs2_ail1_empty_one(sdp, ai, flags))
197 list_move(&ai->ai_list, &sdp->sd_ail2_list);
198 else if (!(flags & DIO_ALL))
202 ret = list_empty(&sdp->sd_ail1_list);
204 gfs2_log_unlock(sdp);
211 * gfs2_ail2_empty_one - Check whether or not a trans in the AIL has been synced
212 * @sdp: the filesystem
217 static void gfs2_ail2_empty_one(struct gfs2_sbd *sdp, struct gfs2_ail *ai)
219 struct list_head *head = &ai->ai_ail2_list;
220 struct gfs2_bufdata *bd;
222 while (!list_empty(head)) {
223 bd = list_entry(head->prev, struct gfs2_bufdata,
225 gfs2_assert(sdp, bd->bd_ail == ai);
227 list_del(&bd->bd_ail_st_list);
228 list_del(&bd->bd_ail_gl_list);
229 atomic_dec(&bd->bd_gl->gl_ail_count);
234 static void ail2_empty(struct gfs2_sbd *sdp, unsigned int new_tail)
236 struct gfs2_ail *ai, *safe;
237 unsigned int old_tail = sdp->sd_log_tail;
238 int wrap = (new_tail < old_tail);
243 list_for_each_entry_safe(ai, safe, &sdp->sd_ail2_list, ai_list) {
244 a = (old_tail <= ai->ai_first);
245 b = (ai->ai_first < new_tail);
246 rm = (wrap) ? (a || b) : (a && b);
250 gfs2_ail2_empty_one(sdp, ai);
251 list_del(&ai->ai_list);
252 gfs2_assert_warn(sdp, list_empty(&ai->ai_ail1_list));
253 gfs2_assert_warn(sdp, list_empty(&ai->ai_ail2_list));
257 gfs2_log_unlock(sdp);
261 * gfs2_log_reserve - Make a log reservation
262 * @sdp: The GFS2 superblock
263 * @blks: The number of blocks to reserve
265 * Note that we never give out the last 6 blocks of the journal. Thats
266 * due to the fact that there is are a small number of header blocks
267 * associated with each log flush. The exact number can't be known until
268 * flush time, so we ensure that we have just enough free blocks at all
269 * times to avoid running out during a log flush.
274 int gfs2_log_reserve(struct gfs2_sbd *sdp, unsigned int blks)
276 unsigned int try = 0;
278 if (gfs2_assert_warn(sdp, blks) ||
279 gfs2_assert_warn(sdp, blks <= sdp->sd_jdesc->jd_blocks))
282 mutex_lock(&sdp->sd_log_reserve_mutex);
284 while(sdp->sd_log_blks_free <= (blks + 6)) {
285 gfs2_log_unlock(sdp);
286 gfs2_ail1_empty(sdp, 0);
287 gfs2_log_flush(sdp, NULL);
290 gfs2_ail1_start(sdp, 0);
293 sdp->sd_log_blks_free -= blks;
294 gfs2_log_unlock(sdp);
295 mutex_unlock(&sdp->sd_log_reserve_mutex);
297 down_read(&sdp->sd_log_flush_lock);
303 * gfs2_log_release - Release a given number of log blocks
304 * @sdp: The GFS2 superblock
305 * @blks: The number of blocks
309 void gfs2_log_release(struct gfs2_sbd *sdp, unsigned int blks)
313 sdp->sd_log_blks_free += blks;
314 gfs2_assert_withdraw(sdp,
315 sdp->sd_log_blks_free <= sdp->sd_jdesc->jd_blocks);
316 gfs2_log_unlock(sdp);
317 up_read(&sdp->sd_log_flush_lock);
320 static u64 log_bmap(struct gfs2_sbd *sdp, unsigned int lbn)
322 struct inode *inode = sdp->sd_jdesc->jd_inode;
324 struct buffer_head bh_map = { .b_state = 0, .b_blocknr = 0 };
326 bh_map.b_size = 1 << inode->i_blkbits;
327 error = gfs2_block_map(inode, lbn, 0, &bh_map);
328 if (error || !bh_map.b_blocknr)
329 printk(KERN_INFO "error=%d, dbn=%llu lbn=%u", error, bh_map.b_blocknr, lbn);
330 gfs2_assert_withdraw(sdp, !error && bh_map.b_blocknr);
332 return bh_map.b_blocknr;
336 * log_distance - Compute distance between two journal blocks
337 * @sdp: The GFS2 superblock
338 * @newer: The most recent journal block of the pair
339 * @older: The older journal block of the pair
341 * Compute the distance (in the journal direction) between two
342 * blocks in the journal
344 * Returns: the distance in blocks
347 static inline unsigned int log_distance(struct gfs2_sbd *sdp, unsigned int newer,
352 dist = newer - older;
354 dist += sdp->sd_jdesc->jd_blocks;
359 static unsigned int current_tail(struct gfs2_sbd *sdp)
366 if (list_empty(&sdp->sd_ail1_list)) {
367 tail = sdp->sd_log_head;
369 ai = list_entry(sdp->sd_ail1_list.prev, struct gfs2_ail, ai_list);
373 gfs2_log_unlock(sdp);
378 static inline void log_incr_head(struct gfs2_sbd *sdp)
380 if (sdp->sd_log_flush_head == sdp->sd_log_tail)
381 gfs2_assert_withdraw(sdp, sdp->sd_log_flush_head == sdp->sd_log_head);
383 if (++sdp->sd_log_flush_head == sdp->sd_jdesc->jd_blocks) {
384 sdp->sd_log_flush_head = 0;
385 sdp->sd_log_flush_wrapped = 1;
390 * gfs2_log_get_buf - Get and initialize a buffer to use for log control data
391 * @sdp: The GFS2 superblock
393 * Returns: the buffer_head
396 struct buffer_head *gfs2_log_get_buf(struct gfs2_sbd *sdp)
398 u64 blkno = log_bmap(sdp, sdp->sd_log_flush_head);
399 struct gfs2_log_buf *lb;
400 struct buffer_head *bh;
402 lb = kzalloc(sizeof(struct gfs2_log_buf), GFP_NOFS | __GFP_NOFAIL);
403 list_add(&lb->lb_list, &sdp->sd_log_flush_list);
405 bh = lb->lb_bh = sb_getblk(sdp->sd_vfs, blkno);
407 memset(bh->b_data, 0, bh->b_size);
408 set_buffer_uptodate(bh);
409 clear_buffer_dirty(bh);
418 * gfs2_log_fake_buf - Build a fake buffer head to write metadata buffer to log
419 * @sdp: the filesystem
420 * @data: the data the buffer_head should point to
422 * Returns: the log buffer descriptor
425 struct buffer_head *gfs2_log_fake_buf(struct gfs2_sbd *sdp,
426 struct buffer_head *real)
428 u64 blkno = log_bmap(sdp, sdp->sd_log_flush_head);
429 struct gfs2_log_buf *lb;
430 struct buffer_head *bh;
432 lb = kzalloc(sizeof(struct gfs2_log_buf), GFP_NOFS | __GFP_NOFAIL);
433 list_add(&lb->lb_list, &sdp->sd_log_flush_list);
436 bh = lb->lb_bh = alloc_buffer_head(GFP_NOFS | __GFP_NOFAIL);
437 atomic_set(&bh->b_count, 1);
438 bh->b_state = (1 << BH_Mapped) | (1 << BH_Uptodate);
439 set_bh_page(bh, real->b_page, bh_offset(real));
440 bh->b_blocknr = blkno;
441 bh->b_size = sdp->sd_sb.sb_bsize;
442 bh->b_bdev = sdp->sd_vfs->s_bdev;
449 static void log_pull_tail(struct gfs2_sbd *sdp, unsigned int new_tail, int pull)
451 unsigned int dist = log_distance(sdp, new_tail, sdp->sd_log_tail);
453 ail2_empty(sdp, new_tail);
456 sdp->sd_log_blks_free += dist - (pull ? 1 : 0);
457 gfs2_assert_withdraw(sdp, sdp->sd_log_blks_free <= sdp->sd_jdesc->jd_blocks);
458 gfs2_log_unlock(sdp);
460 sdp->sd_log_tail = new_tail;
464 * log_write_header - Get and initialize a journal header buffer
465 * @sdp: The GFS2 superblock
467 * Returns: the initialized log buffer descriptor
470 static void log_write_header(struct gfs2_sbd *sdp, u32 flags, int pull)
472 u64 blkno = log_bmap(sdp, sdp->sd_log_flush_head);
473 struct buffer_head *bh;
474 struct gfs2_log_header *lh;
478 bh = sb_getblk(sdp->sd_vfs, blkno);
480 memset(bh->b_data, 0, bh->b_size);
481 set_buffer_uptodate(bh);
482 clear_buffer_dirty(bh);
485 gfs2_ail1_empty(sdp, 0);
486 tail = current_tail(sdp);
488 lh = (struct gfs2_log_header *)bh->b_data;
489 memset(lh, 0, sizeof(struct gfs2_log_header));
490 lh->lh_header.mh_magic = cpu_to_be32(GFS2_MAGIC);
491 lh->lh_header.mh_type = cpu_to_be32(GFS2_METATYPE_LH);
492 lh->lh_header.mh_format = cpu_to_be32(GFS2_FORMAT_LH);
493 lh->lh_sequence = cpu_to_be64(sdp->sd_log_sequence++);
494 lh->lh_flags = cpu_to_be32(flags);
495 lh->lh_tail = cpu_to_be32(tail);
496 lh->lh_blkno = cpu_to_be32(sdp->sd_log_flush_head);
497 hash = gfs2_disk_hash(bh->b_data, sizeof(struct gfs2_log_header));
498 lh->lh_hash = cpu_to_be32(hash);
500 set_buffer_dirty(bh);
501 if (sync_dirty_buffer(bh))
502 gfs2_io_error_bh(sdp, bh);
505 if (sdp->sd_log_tail != tail)
506 log_pull_tail(sdp, tail, pull);
508 gfs2_assert_withdraw(sdp, !pull);
510 sdp->sd_log_idle = (tail == sdp->sd_log_flush_head);
514 static void log_flush_commit(struct gfs2_sbd *sdp)
516 struct list_head *head = &sdp->sd_log_flush_list;
517 struct gfs2_log_buf *lb;
518 struct buffer_head *bh;
520 while (!list_empty(head)) {
521 lb = list_entry(head->next, struct gfs2_log_buf, lb_list);
522 list_del(&lb->lb_list);
526 if (!buffer_uptodate(bh))
527 gfs2_io_error_bh(sdp, bh);
529 while (atomic_read(&bh->b_count) != 1) /* Grrrr... */
531 free_buffer_head(bh);
537 log_write_header(sdp, 0, 0);
541 * gfs2_log_flush - flush incore transaction(s)
542 * @sdp: the filesystem
543 * @gl: The glock structure to flush. If NULL, flush the whole incore log
547 void gfs2_log_flush(struct gfs2_sbd *sdp, struct gfs2_glock *gl)
551 down_write(&sdp->sd_log_flush_lock);
555 if (list_empty(&gl->gl_le.le_list)) {
556 gfs2_log_unlock(sdp);
557 up_write(&sdp->sd_log_flush_lock);
560 gfs2_log_unlock(sdp);
563 ai = kzalloc(sizeof(struct gfs2_ail), GFP_NOFS | __GFP_NOFAIL);
564 INIT_LIST_HEAD(&ai->ai_ail1_list);
565 INIT_LIST_HEAD(&ai->ai_ail2_list);
567 gfs2_assert_withdraw(sdp, sdp->sd_log_num_buf == sdp->sd_log_commited_buf);
568 gfs2_assert_withdraw(sdp,
569 sdp->sd_log_num_revoke == sdp->sd_log_commited_revoke);
571 sdp->sd_log_flush_head = sdp->sd_log_head;
572 sdp->sd_log_flush_wrapped = 0;
573 ai->ai_first = sdp->sd_log_flush_head;
575 lops_before_commit(sdp);
576 if (!list_empty(&sdp->sd_log_flush_list))
577 log_flush_commit(sdp);
578 else if (sdp->sd_log_tail != current_tail(sdp) && !sdp->sd_log_idle)
579 log_write_header(sdp, 0, PULL);
580 lops_after_commit(sdp, ai);
583 sdp->sd_log_head = sdp->sd_log_flush_head;
584 sdp->sd_log_blks_free -= sdp->sd_log_num_hdrs;
585 sdp->sd_log_blks_reserved = 0;
586 sdp->sd_log_commited_buf = 0;
587 sdp->sd_log_num_hdrs = 0;
588 sdp->sd_log_commited_revoke = 0;
590 if (!list_empty(&ai->ai_ail1_list)) {
591 list_add(&ai->ai_list, &sdp->sd_ail1_list);
594 gfs2_log_unlock(sdp);
596 sdp->sd_vfs->s_dirt = 0;
597 up_write(&sdp->sd_log_flush_lock);
602 static void log_refund(struct gfs2_sbd *sdp, struct gfs2_trans *tr)
604 unsigned int reserved = 0;
609 sdp->sd_log_commited_buf += tr->tr_num_buf_new - tr->tr_num_buf_rm;
610 gfs2_assert_withdraw(sdp, ((int)sdp->sd_log_commited_buf) >= 0);
611 sdp->sd_log_commited_revoke += tr->tr_num_revoke - tr->tr_num_revoke_rm;
612 gfs2_assert_withdraw(sdp, ((int)sdp->sd_log_commited_revoke) >= 0);
614 if (sdp->sd_log_commited_buf)
615 reserved += sdp->sd_log_commited_buf;
616 if (sdp->sd_log_commited_revoke)
617 reserved += gfs2_struct2blk(sdp, sdp->sd_log_commited_revoke,
622 old = sdp->sd_log_blks_free;
623 sdp->sd_log_blks_free += tr->tr_reserved -
624 (reserved - sdp->sd_log_blks_reserved);
626 gfs2_assert_withdraw(sdp, sdp->sd_log_blks_free >= old);
627 gfs2_assert_withdraw(sdp,
628 sdp->sd_log_blks_free <= sdp->sd_jdesc->jd_blocks +
629 sdp->sd_log_num_hdrs);
631 sdp->sd_log_blks_reserved = reserved;
633 gfs2_log_unlock(sdp);
637 * gfs2_log_commit - Commit a transaction to the log
638 * @sdp: the filesystem
639 * @tr: the transaction
644 void gfs2_log_commit(struct gfs2_sbd *sdp, struct gfs2_trans *tr)
647 lops_incore_commit(sdp, tr);
649 sdp->sd_vfs->s_dirt = 1;
650 up_read(&sdp->sd_log_flush_lock);
653 if (sdp->sd_log_num_buf > gfs2_tune_get(sdp, gt_incore_log_blocks))
654 wake_up_process(sdp->sd_logd_process);
655 gfs2_log_unlock(sdp);
659 * gfs2_log_shutdown - write a shutdown header into a journal
660 * @sdp: the filesystem
664 void gfs2_log_shutdown(struct gfs2_sbd *sdp)
666 down_write(&sdp->sd_log_flush_lock);
668 gfs2_assert_withdraw(sdp, !sdp->sd_log_blks_reserved);
669 gfs2_assert_withdraw(sdp, !sdp->sd_log_num_gl);
670 gfs2_assert_withdraw(sdp, !sdp->sd_log_num_buf);
671 gfs2_assert_withdraw(sdp, !sdp->sd_log_num_jdata);
672 gfs2_assert_withdraw(sdp, !sdp->sd_log_num_revoke);
673 gfs2_assert_withdraw(sdp, !sdp->sd_log_num_rg);
674 gfs2_assert_withdraw(sdp, !sdp->sd_log_num_databuf);
675 gfs2_assert_withdraw(sdp, !sdp->sd_log_num_hdrs);
676 gfs2_assert_withdraw(sdp, list_empty(&sdp->sd_ail1_list));
678 sdp->sd_log_flush_head = sdp->sd_log_head;
679 sdp->sd_log_flush_wrapped = 0;
681 log_write_header(sdp, GFS2_LOG_HEAD_UNMOUNT, 0);
683 gfs2_assert_warn(sdp, sdp->sd_log_blks_free == sdp->sd_jdesc->jd_blocks);
684 gfs2_assert_warn(sdp, sdp->sd_log_head == sdp->sd_log_tail);
685 gfs2_assert_warn(sdp, list_empty(&sdp->sd_ail2_list));
687 sdp->sd_log_head = sdp->sd_log_flush_head;
688 sdp->sd_log_tail = sdp->sd_log_head;
690 up_write(&sdp->sd_log_flush_lock);
695 * gfs2_meta_syncfs - sync all the buffers in a filesystem
696 * @sdp: the filesystem
700 void gfs2_meta_syncfs(struct gfs2_sbd *sdp)
702 gfs2_log_flush(sdp, NULL);
704 gfs2_ail1_start(sdp, DIO_ALL);
705 if (gfs2_ail1_empty(sdp, DIO_ALL))