[GFS2] Journaled file write/unstuff bug
[powerpc.git] / fs / gfs2 / log.c
1 /*
2  * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
3  * Copyright (C) 2004-2006 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/lm_interface.h>
18 #include <linux/delay.h>
19
20 #include "gfs2.h"
21 #include "incore.h"
22 #include "bmap.h"
23 #include "glock.h"
24 #include "log.h"
25 #include "lops.h"
26 #include "meta_io.h"
27 #include "util.h"
28 #include "dir.h"
29
30 #define PULL 1
31
32 /**
33  * gfs2_struct2blk - compute stuff
34  * @sdp: the filesystem
35  * @nstruct: the number of structures
36  * @ssize: the size of the structures
37  *
38  * Compute the number of log descriptor blocks needed to hold a certain number
39  * of structures of a certain size.
40  *
41  * Returns: the number of blocks needed (minimum is always 1)
42  */
43
44 unsigned int gfs2_struct2blk(struct gfs2_sbd *sdp, unsigned int nstruct,
45                              unsigned int ssize)
46 {
47         unsigned int blks;
48         unsigned int first, second;
49
50         blks = 1;
51         first = (sdp->sd_sb.sb_bsize - sizeof(struct gfs2_log_descriptor)) / ssize;
52
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);
57         }
58
59         return blks;
60 }
61
62 /**
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
66  *
67  */
68
69 static void gfs2_ail1_start_one(struct gfs2_sbd *sdp, struct gfs2_ail *ai)
70 {
71         struct gfs2_bufdata *bd, *s;
72         struct buffer_head *bh;
73         int retry;
74
75         BUG_ON(!spin_is_locked(&sdp->sd_log_lock));
76
77         do {
78                 retry = 0;
79
80                 list_for_each_entry_safe_reverse(bd, s, &ai->ai_ail1_list,
81                                                  bd_ail_st_list) {
82                         bh = bd->bd_bh;
83
84                         gfs2_assert(sdp, bd->bd_ail == ai);
85
86                         if (!bh){
87                                 list_move(&bd->bd_ail_st_list, &ai->ai_ail2_list);
88                                 continue;
89                         }
90
91                         if (!buffer_busy(bh)) {
92                                 if (!buffer_uptodate(bh)) {
93                                         gfs2_log_unlock(sdp);
94                                         gfs2_io_error_bh(sdp, bh);
95                                         gfs2_log_lock(sdp);
96                                 }
97                                 list_move(&bd->bd_ail_st_list, &ai->ai_ail2_list);
98                                 continue;
99                         }
100
101                         if (!buffer_dirty(bh))
102                                 continue;
103
104                         list_move(&bd->bd_ail_st_list, &ai->ai_ail1_list);
105
106                         gfs2_log_unlock(sdp);
107                         wait_on_buffer(bh);
108                         ll_rw_block(WRITE, 1, &bh);
109                         gfs2_log_lock(sdp);
110
111                         retry = 1;
112                         break;
113                 }
114         } while (retry);
115 }
116
117 /**
118  * gfs2_ail1_empty_one - Check whether or not a trans in the AIL has been synced
119  * @sdp: the filesystem
120  * @ai: the AIL entry
121  *
122  */
123
124 static int gfs2_ail1_empty_one(struct gfs2_sbd *sdp, struct gfs2_ail *ai, int flags)
125 {
126         struct gfs2_bufdata *bd, *s;
127         struct buffer_head *bh;
128
129         list_for_each_entry_safe_reverse(bd, s, &ai->ai_ail1_list,
130                                          bd_ail_st_list) {
131                 bh = bd->bd_bh;
132
133                 if (!bh){
134                         list_move(&bd->bd_ail_st_list, &ai->ai_ail2_list);
135                         continue;
136                 }
137
138                 gfs2_assert(sdp, bd->bd_ail == ai);
139
140                 if (buffer_busy(bh)) {
141                         if (flags & DIO_ALL)
142                                 continue;
143                         else
144                                 break;
145                 }
146
147                 if (!buffer_uptodate(bh))
148                         gfs2_io_error_bh(sdp, bh);
149
150                 list_move(&bd->bd_ail_st_list, &ai->ai_ail2_list);
151         }
152
153         return list_empty(&ai->ai_ail1_list);
154 }
155
156 static void gfs2_ail1_start(struct gfs2_sbd *sdp, int flags)
157 {
158         struct list_head *head = &sdp->sd_ail1_list;
159         u64 sync_gen;
160         struct list_head *first;
161         struct gfs2_ail *first_ai, *ai, *tmp;
162         int done = 0;
163
164         gfs2_log_lock(sdp);
165         if (list_empty(head)) {
166                 gfs2_log_unlock(sdp);
167                 return;
168         }
169         sync_gen = sdp->sd_ail_sync_gen++;
170
171         first = head->prev;
172         first_ai = list_entry(first, struct gfs2_ail, ai_list);
173         first_ai->ai_sync_gen = sync_gen;
174         gfs2_ail1_start_one(sdp, first_ai); /* This may drop log lock */
175
176         if (flags & DIO_ALL)
177                 first = NULL;
178
179         while(!done) {
180                 if (first && (head->prev != first ||
181                               gfs2_ail1_empty_one(sdp, first_ai, 0)))
182                         break;
183
184                 done = 1;
185                 list_for_each_entry_safe_reverse(ai, tmp, head, ai_list) {
186                         if (ai->ai_sync_gen >= sync_gen)
187                                 continue;
188                         ai->ai_sync_gen = sync_gen;
189                         gfs2_ail1_start_one(sdp, ai); /* This may drop log lock */
190                         done = 0;
191                         break;
192                 }
193         }
194
195         gfs2_log_unlock(sdp);
196 }
197
198 int gfs2_ail1_empty(struct gfs2_sbd *sdp, int flags)
199 {
200         struct gfs2_ail *ai, *s;
201         int ret;
202
203         gfs2_log_lock(sdp);
204
205         list_for_each_entry_safe_reverse(ai, s, &sdp->sd_ail1_list, ai_list) {
206                 if (gfs2_ail1_empty_one(sdp, ai, flags))
207                         list_move(&ai->ai_list, &sdp->sd_ail2_list);
208                 else if (!(flags & DIO_ALL))
209                         break;
210         }
211
212         ret = list_empty(&sdp->sd_ail1_list);
213
214         gfs2_log_unlock(sdp);
215
216         return ret;
217 }
218
219
220 /**
221  * gfs2_ail2_empty_one - Check whether or not a trans in the AIL has been synced
222  * @sdp: the filesystem
223  * @ai: the AIL entry
224  *
225  */
226
227 static void gfs2_ail2_empty_one(struct gfs2_sbd *sdp, struct gfs2_ail *ai)
228 {
229         struct list_head *head = &ai->ai_ail2_list;
230         struct gfs2_bufdata *bd;
231
232         while (!list_empty(head)) {
233                 bd = list_entry(head->prev, struct gfs2_bufdata,
234                                 bd_ail_st_list);
235                 gfs2_assert(sdp, bd->bd_ail == ai);
236                 bd->bd_ail = NULL;
237                 list_del(&bd->bd_ail_st_list);
238                 list_del(&bd->bd_ail_gl_list);
239                 atomic_dec(&bd->bd_gl->gl_ail_count);
240                 if (bd->bd_bh)
241                         brelse(bd->bd_bh);
242                 else
243                         kmem_cache_free(gfs2_bufdata_cachep, bd);
244         }
245 }
246
247 static void ail2_empty(struct gfs2_sbd *sdp, unsigned int new_tail)
248 {
249         struct gfs2_ail *ai, *safe;
250         unsigned int old_tail = sdp->sd_log_tail;
251         int wrap = (new_tail < old_tail);
252         int a, b, rm;
253
254         gfs2_log_lock(sdp);
255
256         list_for_each_entry_safe(ai, safe, &sdp->sd_ail2_list, ai_list) {
257                 a = (old_tail <= ai->ai_first);
258                 b = (ai->ai_first < new_tail);
259                 rm = (wrap) ? (a || b) : (a && b);
260                 if (!rm)
261                         continue;
262
263                 gfs2_ail2_empty_one(sdp, ai);
264                 list_del(&ai->ai_list);
265                 gfs2_assert_warn(sdp, list_empty(&ai->ai_ail1_list));
266                 gfs2_assert_warn(sdp, list_empty(&ai->ai_ail2_list));
267                 kfree(ai);
268         }
269
270         gfs2_log_unlock(sdp);
271 }
272
273 /**
274  * gfs2_log_reserve - Make a log reservation
275  * @sdp: The GFS2 superblock
276  * @blks: The number of blocks to reserve
277  *
278  * Note that we never give out the last few blocks of the journal. Thats
279  * due to the fact that there is are a small number of header blocks
280  * associated with each log flush. The exact number can't be known until
281  * flush time, so we ensure that we have just enough free blocks at all
282  * times to avoid running out during a log flush.
283  *
284  * Returns: errno
285  */
286
287 int gfs2_log_reserve(struct gfs2_sbd *sdp, unsigned int blks)
288 {
289         unsigned int try = 0;
290         unsigned reserved_blks = 6 * (4096 / sdp->sd_vfs->s_blocksize);
291
292         if (gfs2_assert_warn(sdp, blks) ||
293             gfs2_assert_warn(sdp, blks <= sdp->sd_jdesc->jd_blocks))
294                 return -EINVAL;
295
296         mutex_lock(&sdp->sd_log_reserve_mutex);
297         gfs2_log_lock(sdp);
298         while(sdp->sd_log_blks_free <= (blks + reserved_blks)) {
299                 gfs2_log_unlock(sdp);
300                 gfs2_ail1_empty(sdp, 0);
301                 gfs2_log_flush(sdp, NULL);
302
303                 if (try++)
304                         gfs2_ail1_start(sdp, 0);
305                 gfs2_log_lock(sdp);
306         }
307         sdp->sd_log_blks_free -= blks;
308         gfs2_log_unlock(sdp);
309         mutex_unlock(&sdp->sd_log_reserve_mutex);
310
311         down_read(&sdp->sd_log_flush_lock);
312
313         return 0;
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
323 void gfs2_log_release(struct gfs2_sbd *sdp, unsigned int blks)
324 {
325
326         gfs2_log_lock(sdp);
327         sdp->sd_log_blks_free += blks;
328         gfs2_assert_withdraw(sdp,
329                              sdp->sd_log_blks_free <= sdp->sd_jdesc->jd_blocks);
330         gfs2_log_unlock(sdp);
331         up_read(&sdp->sd_log_flush_lock);
332 }
333
334 static u64 log_bmap(struct gfs2_sbd *sdp, unsigned int lbn)
335 {
336         struct inode *inode = sdp->sd_jdesc->jd_inode;
337         int error;
338         struct buffer_head bh_map = { .b_state = 0, .b_blocknr = 0 };
339
340         bh_map.b_size = 1 << inode->i_blkbits;
341         error = gfs2_block_map(inode, lbn, 0, &bh_map);
342         if (error || !bh_map.b_blocknr)
343                 printk(KERN_INFO "error=%d, dbn=%llu lbn=%u", error,
344                        (unsigned long long)bh_map.b_blocknr, lbn);
345         gfs2_assert_withdraw(sdp, !error && bh_map.b_blocknr);
346
347         return bh_map.b_blocknr;
348 }
349
350 /**
351  * log_distance - Compute distance between two journal blocks
352  * @sdp: The GFS2 superblock
353  * @newer: The most recent journal block of the pair
354  * @older: The older journal block of the pair
355  *
356  *   Compute the distance (in the journal direction) between two
357  *   blocks in the journal
358  *
359  * Returns: the distance in blocks
360  */
361
362 static inline unsigned int log_distance(struct gfs2_sbd *sdp, unsigned int newer,
363                                         unsigned int older)
364 {
365         int dist;
366
367         dist = newer - older;
368         if (dist < 0)
369                 dist += sdp->sd_jdesc->jd_blocks;
370
371         return dist;
372 }
373
374 static unsigned int current_tail(struct gfs2_sbd *sdp)
375 {
376         struct gfs2_ail *ai;
377         unsigned int tail;
378
379         gfs2_log_lock(sdp);
380
381         if (list_empty(&sdp->sd_ail1_list)) {
382                 tail = sdp->sd_log_head;
383         } else {
384                 ai = list_entry(sdp->sd_ail1_list.prev, struct gfs2_ail, ai_list);
385                 tail = ai->ai_first;
386         }
387
388         gfs2_log_unlock(sdp);
389
390         return tail;
391 }
392
393 static inline void log_incr_head(struct gfs2_sbd *sdp)
394 {
395         if (sdp->sd_log_flush_head == sdp->sd_log_tail)
396                 gfs2_assert_withdraw(sdp, sdp->sd_log_flush_head == sdp->sd_log_head);
397
398         if (++sdp->sd_log_flush_head == sdp->sd_jdesc->jd_blocks) {
399                 sdp->sd_log_flush_head = 0;
400                 sdp->sd_log_flush_wrapped = 1;
401         }
402 }
403
404 /**
405  * gfs2_log_get_buf - Get and initialize a buffer to use for log control data
406  * @sdp: The GFS2 superblock
407  *
408  * Returns: the buffer_head
409  */
410
411 struct buffer_head *gfs2_log_get_buf(struct gfs2_sbd *sdp)
412 {
413         u64 blkno = log_bmap(sdp, sdp->sd_log_flush_head);
414         struct gfs2_log_buf *lb;
415         struct buffer_head *bh;
416
417         lb = kzalloc(sizeof(struct gfs2_log_buf), GFP_NOFS | __GFP_NOFAIL);
418         list_add(&lb->lb_list, &sdp->sd_log_flush_list);
419
420         bh = lb->lb_bh = sb_getblk(sdp->sd_vfs, blkno);
421         lock_buffer(bh);
422         memset(bh->b_data, 0, bh->b_size);
423         set_buffer_uptodate(bh);
424         clear_buffer_dirty(bh);
425         unlock_buffer(bh);
426
427         log_incr_head(sdp);
428
429         return bh;
430 }
431
432 /**
433  * gfs2_log_fake_buf - Build a fake buffer head to write metadata buffer to log
434  * @sdp: the filesystem
435  * @data: the data the buffer_head should point to
436  *
437  * Returns: the log buffer descriptor
438  */
439
440 struct buffer_head *gfs2_log_fake_buf(struct gfs2_sbd *sdp,
441                                       struct buffer_head *real)
442 {
443         u64 blkno = log_bmap(sdp, sdp->sd_log_flush_head);
444         struct gfs2_log_buf *lb;
445         struct buffer_head *bh;
446
447         lb = kzalloc(sizeof(struct gfs2_log_buf), GFP_NOFS | __GFP_NOFAIL);
448         list_add(&lb->lb_list, &sdp->sd_log_flush_list);
449         lb->lb_real = real;
450
451         bh = lb->lb_bh = alloc_buffer_head(GFP_NOFS | __GFP_NOFAIL);
452         atomic_set(&bh->b_count, 1);
453         bh->b_state = (1 << BH_Mapped) | (1 << BH_Uptodate);
454         set_bh_page(bh, real->b_page, bh_offset(real));
455         bh->b_blocknr = blkno;
456         bh->b_size = sdp->sd_sb.sb_bsize;
457         bh->b_bdev = sdp->sd_vfs->s_bdev;
458
459         log_incr_head(sdp);
460
461         return bh;
462 }
463
464 static void log_pull_tail(struct gfs2_sbd *sdp, unsigned int new_tail, int pull)
465 {
466         unsigned int dist = log_distance(sdp, new_tail, sdp->sd_log_tail);
467
468         ail2_empty(sdp, new_tail);
469
470         gfs2_log_lock(sdp);
471         sdp->sd_log_blks_free += dist - (pull ? 1 : 0);
472         gfs2_assert_withdraw(sdp, sdp->sd_log_blks_free <= sdp->sd_jdesc->jd_blocks);
473         gfs2_log_unlock(sdp);
474
475         sdp->sd_log_tail = new_tail;
476 }
477
478 /**
479  * log_write_header - Get and initialize a journal header buffer
480  * @sdp: The GFS2 superblock
481  *
482  * Returns: the initialized log buffer descriptor
483  */
484
485 static void log_write_header(struct gfs2_sbd *sdp, u32 flags, int pull)
486 {
487         u64 blkno = log_bmap(sdp, sdp->sd_log_flush_head);
488         struct buffer_head *bh;
489         struct gfs2_log_header *lh;
490         unsigned int tail;
491         u32 hash;
492
493         bh = sb_getblk(sdp->sd_vfs, blkno);
494         lock_buffer(bh);
495         memset(bh->b_data, 0, bh->b_size);
496         set_buffer_uptodate(bh);
497         clear_buffer_dirty(bh);
498         unlock_buffer(bh);
499
500         gfs2_ail1_empty(sdp, 0);
501         tail = current_tail(sdp);
502
503         lh = (struct gfs2_log_header *)bh->b_data;
504         memset(lh, 0, sizeof(struct gfs2_log_header));
505         lh->lh_header.mh_magic = cpu_to_be32(GFS2_MAGIC);
506         lh->lh_header.mh_type = cpu_to_be32(GFS2_METATYPE_LH);
507         lh->lh_header.mh_format = cpu_to_be32(GFS2_FORMAT_LH);
508         lh->lh_sequence = cpu_to_be64(sdp->sd_log_sequence++);
509         lh->lh_flags = cpu_to_be32(flags);
510         lh->lh_tail = cpu_to_be32(tail);
511         lh->lh_blkno = cpu_to_be32(sdp->sd_log_flush_head);
512         hash = gfs2_disk_hash(bh->b_data, sizeof(struct gfs2_log_header));
513         lh->lh_hash = cpu_to_be32(hash);
514
515         set_buffer_dirty(bh);
516         if (sync_dirty_buffer(bh))
517                 gfs2_io_error_bh(sdp, bh);
518         brelse(bh);
519
520         if (sdp->sd_log_tail != tail)
521                 log_pull_tail(sdp, tail, pull);
522         else
523                 gfs2_assert_withdraw(sdp, !pull);
524
525         sdp->sd_log_idle = (tail == sdp->sd_log_flush_head);
526         log_incr_head(sdp);
527 }
528
529 static void log_flush_commit(struct gfs2_sbd *sdp)
530 {
531         struct list_head *head = &sdp->sd_log_flush_list;
532         struct gfs2_log_buf *lb;
533         struct buffer_head *bh;
534
535         while (!list_empty(head)) {
536                 lb = list_entry(head->next, struct gfs2_log_buf, lb_list);
537                 list_del(&lb->lb_list);
538                 bh = lb->lb_bh;
539
540                 wait_on_buffer(bh);
541                 if (!buffer_uptodate(bh))
542                         gfs2_io_error_bh(sdp, bh);
543                 if (lb->lb_real) {
544                         while (atomic_read(&bh->b_count) != 1)  /* Grrrr... */
545                                 schedule();
546                         free_buffer_head(bh);
547                 } else
548                         brelse(bh);
549                 kfree(lb);
550         }
551
552         log_write_header(sdp, 0, 0);
553 }
554
555 /**
556  * gfs2_log_flush - flush incore transaction(s)
557  * @sdp: the filesystem
558  * @gl: The glock structure to flush.  If NULL, flush the whole incore log
559  *
560  */
561
562 void gfs2_log_flush(struct gfs2_sbd *sdp, struct gfs2_glock *gl)
563 {
564         struct gfs2_ail *ai;
565
566         down_write(&sdp->sd_log_flush_lock);
567
568         if (gl) {
569                 gfs2_log_lock(sdp);
570                 if (list_empty(&gl->gl_le.le_list)) {
571                         gfs2_log_unlock(sdp);
572                         up_write(&sdp->sd_log_flush_lock);
573                         return;
574                 }
575                 gfs2_log_unlock(sdp);
576         }
577
578         ai = kzalloc(sizeof(struct gfs2_ail), GFP_NOFS | __GFP_NOFAIL);
579         INIT_LIST_HEAD(&ai->ai_ail1_list);
580         INIT_LIST_HEAD(&ai->ai_ail2_list);
581
582         gfs2_assert_withdraw(sdp, sdp->sd_log_num_buf + sdp->sd_log_num_jdata == sdp->sd_log_commited_buf);
583         gfs2_assert_withdraw(sdp,
584                         sdp->sd_log_num_revoke == sdp->sd_log_commited_revoke);
585
586         sdp->sd_log_flush_head = sdp->sd_log_head;
587         sdp->sd_log_flush_wrapped = 0;
588         ai->ai_first = sdp->sd_log_flush_head;
589
590         lops_before_commit(sdp);
591         if (!list_empty(&sdp->sd_log_flush_list))
592                 log_flush_commit(sdp);
593         else if (sdp->sd_log_tail != current_tail(sdp) && !sdp->sd_log_idle)
594                 log_write_header(sdp, 0, PULL);
595         lops_after_commit(sdp, ai);
596
597         gfs2_log_lock(sdp);
598         sdp->sd_log_head = sdp->sd_log_flush_head;
599         sdp->sd_log_blks_free -= sdp->sd_log_num_hdrs;
600         sdp->sd_log_blks_reserved = 0;
601         sdp->sd_log_commited_buf = 0;
602         sdp->sd_log_num_hdrs = 0;
603         sdp->sd_log_commited_revoke = 0;
604
605         if (!list_empty(&ai->ai_ail1_list)) {
606                 list_add(&ai->ai_list, &sdp->sd_ail1_list);
607                 ai = NULL;
608         }
609         gfs2_log_unlock(sdp);
610
611         sdp->sd_vfs->s_dirt = 0;
612         up_write(&sdp->sd_log_flush_lock);
613
614         kfree(ai);
615 }
616
617 static void log_refund(struct gfs2_sbd *sdp, struct gfs2_trans *tr)
618 {
619         unsigned int reserved = 0;
620         unsigned int old;
621
622         gfs2_log_lock(sdp);
623
624         sdp->sd_log_commited_buf += tr->tr_num_buf_new - tr->tr_num_buf_rm;
625         gfs2_assert_withdraw(sdp, ((int)sdp->sd_log_commited_buf) >= 0);
626         sdp->sd_log_commited_revoke += tr->tr_num_revoke - tr->tr_num_revoke_rm;
627         gfs2_assert_withdraw(sdp, ((int)sdp->sd_log_commited_revoke) >= 0);
628
629         if (sdp->sd_log_commited_buf)
630                 reserved += sdp->sd_log_commited_buf;
631         if (sdp->sd_log_commited_revoke)
632                 reserved += gfs2_struct2blk(sdp, sdp->sd_log_commited_revoke,
633                                             sizeof(u64));
634         if (reserved)
635                 reserved++;
636
637         old = sdp->sd_log_blks_free;
638         sdp->sd_log_blks_free += tr->tr_reserved -
639                                  (reserved - sdp->sd_log_blks_reserved);
640
641         gfs2_assert_withdraw(sdp, sdp->sd_log_blks_free >= old);
642         gfs2_assert_withdraw(sdp,
643                              sdp->sd_log_blks_free <= sdp->sd_jdesc->jd_blocks +
644                              sdp->sd_log_num_hdrs);
645
646         sdp->sd_log_blks_reserved = reserved;
647
648         gfs2_log_unlock(sdp);
649 }
650
651 /**
652  * gfs2_log_commit - Commit a transaction to the log
653  * @sdp: the filesystem
654  * @tr: the transaction
655  *
656  * Returns: errno
657  */
658
659 void gfs2_log_commit(struct gfs2_sbd *sdp, struct gfs2_trans *tr)
660 {
661         log_refund(sdp, tr);
662         lops_incore_commit(sdp, tr);
663
664         sdp->sd_vfs->s_dirt = 1;
665         up_read(&sdp->sd_log_flush_lock);
666
667         gfs2_log_lock(sdp);
668         if (sdp->sd_log_num_buf > gfs2_tune_get(sdp, gt_incore_log_blocks))
669                 wake_up_process(sdp->sd_logd_process);
670         gfs2_log_unlock(sdp);
671 }
672
673 /**
674  * gfs2_log_shutdown - write a shutdown header into a journal
675  * @sdp: the filesystem
676  *
677  */
678
679 void gfs2_log_shutdown(struct gfs2_sbd *sdp)
680 {
681         down_write(&sdp->sd_log_flush_lock);
682
683         gfs2_assert_withdraw(sdp, !sdp->sd_log_blks_reserved);
684         gfs2_assert_withdraw(sdp, !sdp->sd_log_num_gl);
685         gfs2_assert_withdraw(sdp, !sdp->sd_log_num_buf);
686         gfs2_assert_withdraw(sdp, !sdp->sd_log_num_jdata);
687         gfs2_assert_withdraw(sdp, !sdp->sd_log_num_revoke);
688         gfs2_assert_withdraw(sdp, !sdp->sd_log_num_rg);
689         gfs2_assert_withdraw(sdp, !sdp->sd_log_num_databuf);
690         gfs2_assert_withdraw(sdp, !sdp->sd_log_num_hdrs);
691         gfs2_assert_withdraw(sdp, list_empty(&sdp->sd_ail1_list));
692
693         sdp->sd_log_flush_head = sdp->sd_log_head;
694         sdp->sd_log_flush_wrapped = 0;
695
696         log_write_header(sdp, GFS2_LOG_HEAD_UNMOUNT, 0);
697
698         gfs2_assert_warn(sdp, sdp->sd_log_blks_free == sdp->sd_jdesc->jd_blocks);
699         gfs2_assert_warn(sdp, sdp->sd_log_head == sdp->sd_log_tail);
700         gfs2_assert_warn(sdp, list_empty(&sdp->sd_ail2_list));
701
702         sdp->sd_log_head = sdp->sd_log_flush_head;
703         sdp->sd_log_tail = sdp->sd_log_head;
704
705         up_write(&sdp->sd_log_flush_lock);
706 }
707
708
709 /**
710  * gfs2_meta_syncfs - sync all the buffers in a filesystem
711  * @sdp: the filesystem
712  *
713  */
714
715 void gfs2_meta_syncfs(struct gfs2_sbd *sdp)
716 {
717         gfs2_log_flush(sdp, NULL);
718         for (;;) {
719                 gfs2_ail1_start(sdp, DIO_ALL);
720                 if (gfs2_ail1_empty(sdp, DIO_ALL))
721                         break;
722                 msleep(10);
723         }
724 }
725