Merge tag 'gfs2-merge-window' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2...
[cascardo/linux.git] / fs / gfs2 / lops.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/mempool.h>
16 #include <linux/gfs2_ondisk.h>
17 #include <linux/bio.h>
18 #include <linux/fs.h>
19 #include <linux/list_sort.h>
20
21 #include "gfs2.h"
22 #include "incore.h"
23 #include "inode.h"
24 #include "glock.h"
25 #include "log.h"
26 #include "lops.h"
27 #include "meta_io.h"
28 #include "recovery.h"
29 #include "rgrp.h"
30 #include "trans.h"
31 #include "util.h"
32 #include "trace_gfs2.h"
33
34 /**
35  * gfs2_pin - Pin a buffer in memory
36  * @sdp: The superblock
37  * @bh: The buffer to be pinned
38  *
39  * The log lock must be held when calling this function
40  */
41 void gfs2_pin(struct gfs2_sbd *sdp, struct buffer_head *bh)
42 {
43         struct gfs2_bufdata *bd;
44
45         BUG_ON(!current->journal_info);
46
47         clear_buffer_dirty(bh);
48         if (test_set_buffer_pinned(bh))
49                 gfs2_assert_withdraw(sdp, 0);
50         if (!buffer_uptodate(bh))
51                 gfs2_io_error_bh(sdp, bh);
52         bd = bh->b_private;
53         /* If this buffer is in the AIL and it has already been written
54          * to in-place disk block, remove it from the AIL.
55          */
56         spin_lock(&sdp->sd_ail_lock);
57         if (bd->bd_tr)
58                 list_move(&bd->bd_ail_st_list, &bd->bd_tr->tr_ail2_list);
59         spin_unlock(&sdp->sd_ail_lock);
60         get_bh(bh);
61         atomic_inc(&sdp->sd_log_pinned);
62         trace_gfs2_pin(bd, 1);
63 }
64
65 static bool buffer_is_rgrp(const struct gfs2_bufdata *bd)
66 {
67         return bd->bd_gl->gl_name.ln_type == LM_TYPE_RGRP;
68 }
69
70 static void maybe_release_space(struct gfs2_bufdata *bd)
71 {
72         struct gfs2_glock *gl = bd->bd_gl;
73         struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
74         struct gfs2_rgrpd *rgd = gl->gl_object;
75         unsigned int index = bd->bd_bh->b_blocknr - gl->gl_name.ln_number;
76         struct gfs2_bitmap *bi = rgd->rd_bits + index;
77
78         if (bi->bi_clone == NULL)
79                 return;
80         if (sdp->sd_args.ar_discard)
81                 gfs2_rgrp_send_discards(sdp, rgd->rd_data0, bd->bd_bh, bi, 1, NULL);
82         memcpy(bi->bi_clone + bi->bi_offset,
83                bd->bd_bh->b_data + bi->bi_offset, bi->bi_len);
84         clear_bit(GBF_FULL, &bi->bi_flags);
85         rgd->rd_free_clone = rgd->rd_free;
86         rgd->rd_extfail_pt = rgd->rd_free;
87 }
88
89 /**
90  * gfs2_unpin - Unpin a buffer
91  * @sdp: the filesystem the buffer belongs to
92  * @bh: The buffer to unpin
93  * @ai:
94  * @flags: The inode dirty flags
95  *
96  */
97
98 static void gfs2_unpin(struct gfs2_sbd *sdp, struct buffer_head *bh,
99                        struct gfs2_trans *tr)
100 {
101         struct gfs2_bufdata *bd = bh->b_private;
102
103         BUG_ON(!buffer_uptodate(bh));
104         BUG_ON(!buffer_pinned(bh));
105
106         lock_buffer(bh);
107         mark_buffer_dirty(bh);
108         clear_buffer_pinned(bh);
109
110         if (buffer_is_rgrp(bd))
111                 maybe_release_space(bd);
112
113         spin_lock(&sdp->sd_ail_lock);
114         if (bd->bd_tr) {
115                 list_del(&bd->bd_ail_st_list);
116                 brelse(bh);
117         } else {
118                 struct gfs2_glock *gl = bd->bd_gl;
119                 list_add(&bd->bd_ail_gl_list, &gl->gl_ail_list);
120                 atomic_inc(&gl->gl_ail_count);
121         }
122         bd->bd_tr = tr;
123         list_add(&bd->bd_ail_st_list, &tr->tr_ail1_list);
124         spin_unlock(&sdp->sd_ail_lock);
125
126         clear_bit(GLF_LFLUSH, &bd->bd_gl->gl_flags);
127         trace_gfs2_pin(bd, 0);
128         unlock_buffer(bh);
129         atomic_dec(&sdp->sd_log_pinned);
130 }
131
132 static void gfs2_log_incr_head(struct gfs2_sbd *sdp)
133 {
134         BUG_ON((sdp->sd_log_flush_head == sdp->sd_log_tail) &&
135                (sdp->sd_log_flush_head != sdp->sd_log_head));
136
137         if (++sdp->sd_log_flush_head == sdp->sd_jdesc->jd_blocks) {
138                 sdp->sd_log_flush_head = 0;
139                 sdp->sd_log_flush_wrapped = 1;
140         }
141 }
142
143 static u64 gfs2_log_bmap(struct gfs2_sbd *sdp)
144 {
145         unsigned int lbn = sdp->sd_log_flush_head;
146         struct gfs2_journal_extent *je;
147         u64 block;
148
149         list_for_each_entry(je, &sdp->sd_jdesc->extent_list, list) {
150                 if ((lbn >= je->lblock) && (lbn < (je->lblock + je->blocks))) {
151                         block = je->dblock + lbn - je->lblock;
152                         gfs2_log_incr_head(sdp);
153                         return block;
154                 }
155         }
156
157         return -1;
158 }
159
160 /**
161  * gfs2_end_log_write_bh - end log write of pagecache data with buffers
162  * @sdp: The superblock
163  * @bvec: The bio_vec
164  * @error: The i/o status
165  *
166  * This finds the relavent buffers and unlocks then and sets the
167  * error flag according to the status of the i/o request. This is
168  * used when the log is writing data which has an in-place version
169  * that is pinned in the pagecache.
170  */
171
172 static void gfs2_end_log_write_bh(struct gfs2_sbd *sdp, struct bio_vec *bvec,
173                                   int error)
174 {
175         struct buffer_head *bh, *next;
176         struct page *page = bvec->bv_page;
177         unsigned size;
178
179         bh = page_buffers(page);
180         size = bvec->bv_len;
181         while (bh_offset(bh) < bvec->bv_offset)
182                 bh = bh->b_this_page;
183         do {
184                 if (error)
185                         set_buffer_write_io_error(bh);
186                 unlock_buffer(bh);
187                 next = bh->b_this_page;
188                 size -= bh->b_size;
189                 brelse(bh);
190                 bh = next;
191         } while(bh && size);
192 }
193
194 /**
195  * gfs2_end_log_write - end of i/o to the log
196  * @bio: The bio
197  * @error: Status of i/o request
198  *
199  * Each bio_vec contains either data from the pagecache or data
200  * relating to the log itself. Here we iterate over the bio_vec
201  * array, processing both kinds of data.
202  *
203  */
204
205 static void gfs2_end_log_write(struct bio *bio)
206 {
207         struct gfs2_sbd *sdp = bio->bi_private;
208         struct bio_vec *bvec;
209         struct page *page;
210         int i;
211
212         if (bio->bi_error) {
213                 sdp->sd_log_error = bio->bi_error;
214                 fs_err(sdp, "Error %d writing to log\n", bio->bi_error);
215         }
216
217         bio_for_each_segment_all(bvec, bio, i) {
218                 page = bvec->bv_page;
219                 if (page_has_buffers(page))
220                         gfs2_end_log_write_bh(sdp, bvec, bio->bi_error);
221                 else
222                         mempool_free(page, gfs2_page_pool);
223         }
224
225         bio_put(bio);
226         if (atomic_dec_and_test(&sdp->sd_log_in_flight))
227                 wake_up(&sdp->sd_log_flush_wait);
228 }
229
230 /**
231  * gfs2_log_flush_bio - Submit any pending log bio
232  * @sdp: The superblock
233  * @rw: The rw flags
234  *
235  * Submit any pending part-built or full bio to the block device. If
236  * there is no pending bio, then this is a no-op.
237  */
238
239 void gfs2_log_flush_bio(struct gfs2_sbd *sdp, int rw)
240 {
241         if (sdp->sd_log_bio) {
242                 atomic_inc(&sdp->sd_log_in_flight);
243                 submit_bio(rw, sdp->sd_log_bio);
244                 sdp->sd_log_bio = NULL;
245         }
246 }
247
248 /**
249  * gfs2_log_alloc_bio - Allocate a new bio for log writing
250  * @sdp: The superblock
251  * @blkno: The next device block number we want to write to
252  *
253  * This should never be called when there is a cached bio in the
254  * super block. When it returns, there will be a cached bio in the
255  * super block which will have as many bio_vecs as the device is
256  * happy to handle.
257  *
258  * Returns: Newly allocated bio
259  */
260
261 static struct bio *gfs2_log_alloc_bio(struct gfs2_sbd *sdp, u64 blkno)
262 {
263         struct super_block *sb = sdp->sd_vfs;
264         struct bio *bio;
265
266         BUG_ON(sdp->sd_log_bio);
267
268         bio = bio_alloc(GFP_NOIO, BIO_MAX_PAGES);
269         bio->bi_iter.bi_sector = blkno * (sb->s_blocksize >> 9);
270         bio->bi_bdev = sb->s_bdev;
271         bio->bi_end_io = gfs2_end_log_write;
272         bio->bi_private = sdp;
273
274         sdp->sd_log_bio = bio;
275
276         return bio;
277 }
278
279 /**
280  * gfs2_log_get_bio - Get cached log bio, or allocate a new one
281  * @sdp: The superblock
282  * @blkno: The device block number we want to write to
283  *
284  * If there is a cached bio, then if the next block number is sequential
285  * with the previous one, return it, otherwise flush the bio to the
286  * device. If there is not a cached bio, or we just flushed it, then
287  * allocate a new one.
288  *
289  * Returns: The bio to use for log writes
290  */
291
292 static struct bio *gfs2_log_get_bio(struct gfs2_sbd *sdp, u64 blkno)
293 {
294         struct bio *bio = sdp->sd_log_bio;
295         u64 nblk;
296
297         if (bio) {
298                 nblk = bio_end_sector(bio);
299                 nblk >>= sdp->sd_fsb2bb_shift;
300                 if (blkno == nblk)
301                         return bio;
302                 gfs2_log_flush_bio(sdp, WRITE);
303         }
304
305         return gfs2_log_alloc_bio(sdp, blkno);
306 }
307
308
309 /**
310  * gfs2_log_write - write to log
311  * @sdp: the filesystem
312  * @page: the page to write
313  * @size: the size of the data to write
314  * @offset: the offset within the page 
315  *
316  * Try and add the page segment to the current bio. If that fails,
317  * submit the current bio to the device and create a new one, and
318  * then add the page segment to that.
319  */
320
321 static void gfs2_log_write(struct gfs2_sbd *sdp, struct page *page,
322                            unsigned size, unsigned offset)
323 {
324         u64 blkno = gfs2_log_bmap(sdp);
325         struct bio *bio;
326         int ret;
327
328         bio = gfs2_log_get_bio(sdp, blkno);
329         ret = bio_add_page(bio, page, size, offset);
330         if (ret == 0) {
331                 gfs2_log_flush_bio(sdp, WRITE);
332                 bio = gfs2_log_alloc_bio(sdp, blkno);
333                 ret = bio_add_page(bio, page, size, offset);
334                 WARN_ON(ret == 0);
335         }
336 }
337
338 /**
339  * gfs2_log_write_bh - write a buffer's content to the log
340  * @sdp: The super block
341  * @bh: The buffer pointing to the in-place location
342  * 
343  * This writes the content of the buffer to the next available location
344  * in the log. The buffer will be unlocked once the i/o to the log has
345  * completed.
346  */
347
348 static void gfs2_log_write_bh(struct gfs2_sbd *sdp, struct buffer_head *bh)
349 {
350         gfs2_log_write(sdp, bh->b_page, bh->b_size, bh_offset(bh));
351 }
352
353 /**
354  * gfs2_log_write_page - write one block stored in a page, into the log
355  * @sdp: The superblock
356  * @page: The struct page
357  *
358  * This writes the first block-sized part of the page into the log. Note
359  * that the page must have been allocated from the gfs2_page_pool mempool
360  * and that after this has been called, ownership has been transferred and
361  * the page may be freed at any time.
362  */
363
364 void gfs2_log_write_page(struct gfs2_sbd *sdp, struct page *page)
365 {
366         struct super_block *sb = sdp->sd_vfs;
367         gfs2_log_write(sdp, page, sb->s_blocksize, 0);
368 }
369
370 static struct page *gfs2_get_log_desc(struct gfs2_sbd *sdp, u32 ld_type,
371                                       u32 ld_length, u32 ld_data1)
372 {
373         struct page *page = mempool_alloc(gfs2_page_pool, GFP_NOIO);
374         struct gfs2_log_descriptor *ld = page_address(page);
375         clear_page(ld);
376         ld->ld_header.mh_magic = cpu_to_be32(GFS2_MAGIC);
377         ld->ld_header.mh_type = cpu_to_be32(GFS2_METATYPE_LD);
378         ld->ld_header.mh_format = cpu_to_be32(GFS2_FORMAT_LD);
379         ld->ld_type = cpu_to_be32(ld_type);
380         ld->ld_length = cpu_to_be32(ld_length);
381         ld->ld_data1 = cpu_to_be32(ld_data1);
382         ld->ld_data2 = 0;
383         return page;
384 }
385
386 static void gfs2_check_magic(struct buffer_head *bh)
387 {
388         void *kaddr;
389         __be32 *ptr;
390
391         clear_buffer_escaped(bh);
392         kaddr = kmap_atomic(bh->b_page);
393         ptr = kaddr + bh_offset(bh);
394         if (*ptr == cpu_to_be32(GFS2_MAGIC))
395                 set_buffer_escaped(bh);
396         kunmap_atomic(kaddr);
397 }
398
399 static int blocknr_cmp(void *priv, struct list_head *a, struct list_head *b)
400 {
401         struct gfs2_bufdata *bda, *bdb;
402
403         bda = list_entry(a, struct gfs2_bufdata, bd_list);
404         bdb = list_entry(b, struct gfs2_bufdata, bd_list);
405
406         if (bda->bd_bh->b_blocknr < bdb->bd_bh->b_blocknr)
407                 return -1;
408         if (bda->bd_bh->b_blocknr > bdb->bd_bh->b_blocknr)
409                 return 1;
410         return 0;
411 }
412
413 static void gfs2_before_commit(struct gfs2_sbd *sdp, unsigned int limit,
414                                 unsigned int total, struct list_head *blist,
415                                 bool is_databuf)
416 {
417         struct gfs2_log_descriptor *ld;
418         struct gfs2_bufdata *bd1 = NULL, *bd2;
419         struct page *page;
420         unsigned int num;
421         unsigned n;
422         __be64 *ptr;
423
424         gfs2_log_lock(sdp);
425         list_sort(NULL, blist, blocknr_cmp);
426         bd1 = bd2 = list_prepare_entry(bd1, blist, bd_list);
427         while(total) {
428                 num = total;
429                 if (total > limit)
430                         num = limit;
431                 gfs2_log_unlock(sdp);
432                 page = gfs2_get_log_desc(sdp,
433                                          is_databuf ? GFS2_LOG_DESC_JDATA :
434                                          GFS2_LOG_DESC_METADATA, num + 1, num);
435                 ld = page_address(page);
436                 gfs2_log_lock(sdp);
437                 ptr = (__be64 *)(ld + 1);
438
439                 n = 0;
440                 list_for_each_entry_continue(bd1, blist, bd_list) {
441                         *ptr++ = cpu_to_be64(bd1->bd_bh->b_blocknr);
442                         if (is_databuf) {
443                                 gfs2_check_magic(bd1->bd_bh);
444                                 *ptr++ = cpu_to_be64(buffer_escaped(bd1->bd_bh) ? 1 : 0);
445                         }
446                         if (++n >= num)
447                                 break;
448                 }
449
450                 gfs2_log_unlock(sdp);
451                 gfs2_log_write_page(sdp, page);
452                 gfs2_log_lock(sdp);
453
454                 n = 0;
455                 list_for_each_entry_continue(bd2, blist, bd_list) {
456                         get_bh(bd2->bd_bh);
457                         gfs2_log_unlock(sdp);
458                         lock_buffer(bd2->bd_bh);
459
460                         if (buffer_escaped(bd2->bd_bh)) {
461                                 void *kaddr;
462                                 page = mempool_alloc(gfs2_page_pool, GFP_NOIO);
463                                 ptr = page_address(page);
464                                 kaddr = kmap_atomic(bd2->bd_bh->b_page);
465                                 memcpy(ptr, kaddr + bh_offset(bd2->bd_bh),
466                                        bd2->bd_bh->b_size);
467                                 kunmap_atomic(kaddr);
468                                 *(__be32 *)ptr = 0;
469                                 clear_buffer_escaped(bd2->bd_bh);
470                                 unlock_buffer(bd2->bd_bh);
471                                 brelse(bd2->bd_bh);
472                                 gfs2_log_write_page(sdp, page);
473                         } else {
474                                 gfs2_log_write_bh(sdp, bd2->bd_bh);
475                         }
476                         gfs2_log_lock(sdp);
477                         if (++n >= num)
478                                 break;
479                 }
480
481                 BUG_ON(total < num);
482                 total -= num;
483         }
484         gfs2_log_unlock(sdp);
485 }
486
487 static void buf_lo_before_commit(struct gfs2_sbd *sdp, struct gfs2_trans *tr)
488 {
489         unsigned int limit = buf_limit(sdp); /* 503 for 4k blocks */
490         unsigned int nbuf;
491         if (tr == NULL)
492                 return;
493         nbuf = tr->tr_num_buf_new - tr->tr_num_buf_rm;
494         gfs2_before_commit(sdp, limit, nbuf, &tr->tr_buf, 0);
495 }
496
497 static void buf_lo_after_commit(struct gfs2_sbd *sdp, struct gfs2_trans *tr)
498 {
499         struct list_head *head;
500         struct gfs2_bufdata *bd;
501
502         if (tr == NULL)
503                 return;
504
505         head = &tr->tr_buf;
506         while (!list_empty(head)) {
507                 bd = list_entry(head->next, struct gfs2_bufdata, bd_list);
508                 list_del_init(&bd->bd_list);
509                 gfs2_unpin(sdp, bd->bd_bh, tr);
510         }
511 }
512
513 static void buf_lo_before_scan(struct gfs2_jdesc *jd,
514                                struct gfs2_log_header_host *head, int pass)
515 {
516         if (pass != 0)
517                 return;
518
519         jd->jd_found_blocks = 0;
520         jd->jd_replayed_blocks = 0;
521 }
522
523 static int buf_lo_scan_elements(struct gfs2_jdesc *jd, unsigned int start,
524                                 struct gfs2_log_descriptor *ld, __be64 *ptr,
525                                 int pass)
526 {
527         struct gfs2_inode *ip = GFS2_I(jd->jd_inode);
528         struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
529         struct gfs2_glock *gl = ip->i_gl;
530         unsigned int blks = be32_to_cpu(ld->ld_data1);
531         struct buffer_head *bh_log, *bh_ip;
532         u64 blkno;
533         int error = 0;
534
535         if (pass != 1 || be32_to_cpu(ld->ld_type) != GFS2_LOG_DESC_METADATA)
536                 return 0;
537
538         gfs2_replay_incr_blk(sdp, &start);
539
540         for (; blks; gfs2_replay_incr_blk(sdp, &start), blks--) {
541                 blkno = be64_to_cpu(*ptr++);
542
543                 jd->jd_found_blocks++;
544
545                 if (gfs2_revoke_check(jd, blkno, start))
546                         continue;
547
548                 error = gfs2_replay_read_block(jd, start, &bh_log);
549                 if (error)
550                         return error;
551
552                 bh_ip = gfs2_meta_new(gl, blkno);
553                 memcpy(bh_ip->b_data, bh_log->b_data, bh_log->b_size);
554
555                 if (gfs2_meta_check(sdp, bh_ip))
556                         error = -EIO;
557                 else
558                         mark_buffer_dirty(bh_ip);
559
560                 brelse(bh_log);
561                 brelse(bh_ip);
562
563                 if (error)
564                         break;
565
566                 jd->jd_replayed_blocks++;
567         }
568
569         return error;
570 }
571
572 /**
573  * gfs2_meta_sync - Sync all buffers associated with a glock
574  * @gl: The glock
575  *
576  */
577
578 static void gfs2_meta_sync(struct gfs2_glock *gl)
579 {
580         struct address_space *mapping = gfs2_glock2aspace(gl);
581         struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
582         int error;
583
584         if (mapping == NULL)
585                 mapping = &sdp->sd_aspace;
586
587         filemap_fdatawrite(mapping);
588         error = filemap_fdatawait(mapping);
589
590         if (error)
591                 gfs2_io_error(gl->gl_name.ln_sbd);
592 }
593
594 static void buf_lo_after_scan(struct gfs2_jdesc *jd, int error, int pass)
595 {
596         struct gfs2_inode *ip = GFS2_I(jd->jd_inode);
597         struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
598
599         if (error) {
600                 gfs2_meta_sync(ip->i_gl);
601                 return;
602         }
603         if (pass != 1)
604                 return;
605
606         gfs2_meta_sync(ip->i_gl);
607
608         fs_info(sdp, "jid=%u: Replayed %u of %u blocks\n",
609                 jd->jd_jid, jd->jd_replayed_blocks, jd->jd_found_blocks);
610 }
611
612 static void revoke_lo_before_commit(struct gfs2_sbd *sdp, struct gfs2_trans *tr)
613 {
614         struct gfs2_meta_header *mh;
615         unsigned int offset;
616         struct list_head *head = &sdp->sd_log_le_revoke;
617         struct gfs2_bufdata *bd;
618         struct page *page;
619         unsigned int length;
620
621         gfs2_write_revokes(sdp);
622         if (!sdp->sd_log_num_revoke)
623                 return;
624
625         length = gfs2_struct2blk(sdp, sdp->sd_log_num_revoke, sizeof(u64));
626         page = gfs2_get_log_desc(sdp, GFS2_LOG_DESC_REVOKE, length, sdp->sd_log_num_revoke);
627         offset = sizeof(struct gfs2_log_descriptor);
628
629         list_for_each_entry(bd, head, bd_list) {
630                 sdp->sd_log_num_revoke--;
631
632                 if (offset + sizeof(u64) > sdp->sd_sb.sb_bsize) {
633
634                         gfs2_log_write_page(sdp, page);
635                         page = mempool_alloc(gfs2_page_pool, GFP_NOIO);
636                         mh = page_address(page);
637                         clear_page(mh);
638                         mh->mh_magic = cpu_to_be32(GFS2_MAGIC);
639                         mh->mh_type = cpu_to_be32(GFS2_METATYPE_LB);
640                         mh->mh_format = cpu_to_be32(GFS2_FORMAT_LB);
641                         offset = sizeof(struct gfs2_meta_header);
642                 }
643
644                 *(__be64 *)(page_address(page) + offset) = cpu_to_be64(bd->bd_blkno);
645                 offset += sizeof(u64);
646         }
647         gfs2_assert_withdraw(sdp, !sdp->sd_log_num_revoke);
648
649         gfs2_log_write_page(sdp, page);
650 }
651
652 static void revoke_lo_after_commit(struct gfs2_sbd *sdp, struct gfs2_trans *tr)
653 {
654         struct list_head *head = &sdp->sd_log_le_revoke;
655         struct gfs2_bufdata *bd;
656         struct gfs2_glock *gl;
657
658         while (!list_empty(head)) {
659                 bd = list_entry(head->next, struct gfs2_bufdata, bd_list);
660                 list_del_init(&bd->bd_list);
661                 gl = bd->bd_gl;
662                 atomic_dec(&gl->gl_revokes);
663                 clear_bit(GLF_LFLUSH, &gl->gl_flags);
664                 kmem_cache_free(gfs2_bufdata_cachep, bd);
665         }
666 }
667
668 static void revoke_lo_before_scan(struct gfs2_jdesc *jd,
669                                   struct gfs2_log_header_host *head, int pass)
670 {
671         if (pass != 0)
672                 return;
673
674         jd->jd_found_revokes = 0;
675         jd->jd_replay_tail = head->lh_tail;
676 }
677
678 static int revoke_lo_scan_elements(struct gfs2_jdesc *jd, unsigned int start,
679                                    struct gfs2_log_descriptor *ld, __be64 *ptr,
680                                    int pass)
681 {
682         struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
683         unsigned int blks = be32_to_cpu(ld->ld_length);
684         unsigned int revokes = be32_to_cpu(ld->ld_data1);
685         struct buffer_head *bh;
686         unsigned int offset;
687         u64 blkno;
688         int first = 1;
689         int error;
690
691         if (pass != 0 || be32_to_cpu(ld->ld_type) != GFS2_LOG_DESC_REVOKE)
692                 return 0;
693
694         offset = sizeof(struct gfs2_log_descriptor);
695
696         for (; blks; gfs2_replay_incr_blk(sdp, &start), blks--) {
697                 error = gfs2_replay_read_block(jd, start, &bh);
698                 if (error)
699                         return error;
700
701                 if (!first)
702                         gfs2_metatype_check(sdp, bh, GFS2_METATYPE_LB);
703
704                 while (offset + sizeof(u64) <= sdp->sd_sb.sb_bsize) {
705                         blkno = be64_to_cpu(*(__be64 *)(bh->b_data + offset));
706
707                         error = gfs2_revoke_add(jd, blkno, start);
708                         if (error < 0) {
709                                 brelse(bh);
710                                 return error;
711                         }
712                         else if (error)
713                                 jd->jd_found_revokes++;
714
715                         if (!--revokes)
716                                 break;
717                         offset += sizeof(u64);
718                 }
719
720                 brelse(bh);
721                 offset = sizeof(struct gfs2_meta_header);
722                 first = 0;
723         }
724
725         return 0;
726 }
727
728 static void revoke_lo_after_scan(struct gfs2_jdesc *jd, int error, int pass)
729 {
730         struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
731
732         if (error) {
733                 gfs2_revoke_clean(jd);
734                 return;
735         }
736         if (pass != 1)
737                 return;
738
739         fs_info(sdp, "jid=%u: Found %u revoke tags\n",
740                 jd->jd_jid, jd->jd_found_revokes);
741
742         gfs2_revoke_clean(jd);
743 }
744
745 /**
746  * databuf_lo_before_commit - Scan the data buffers, writing as we go
747  *
748  */
749
750 static void databuf_lo_before_commit(struct gfs2_sbd *sdp, struct gfs2_trans *tr)
751 {
752         unsigned int limit = databuf_limit(sdp);
753         unsigned int nbuf;
754         if (tr == NULL)
755                 return;
756         nbuf = tr->tr_num_databuf_new - tr->tr_num_databuf_rm;
757         gfs2_before_commit(sdp, limit, nbuf, &tr->tr_databuf, 1);
758 }
759
760 static int databuf_lo_scan_elements(struct gfs2_jdesc *jd, unsigned int start,
761                                     struct gfs2_log_descriptor *ld,
762                                     __be64 *ptr, int pass)
763 {
764         struct gfs2_inode *ip = GFS2_I(jd->jd_inode);
765         struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
766         struct gfs2_glock *gl = ip->i_gl;
767         unsigned int blks = be32_to_cpu(ld->ld_data1);
768         struct buffer_head *bh_log, *bh_ip;
769         u64 blkno;
770         u64 esc;
771         int error = 0;
772
773         if (pass != 1 || be32_to_cpu(ld->ld_type) != GFS2_LOG_DESC_JDATA)
774                 return 0;
775
776         gfs2_replay_incr_blk(sdp, &start);
777         for (; blks; gfs2_replay_incr_blk(sdp, &start), blks--) {
778                 blkno = be64_to_cpu(*ptr++);
779                 esc = be64_to_cpu(*ptr++);
780
781                 jd->jd_found_blocks++;
782
783                 if (gfs2_revoke_check(jd, blkno, start))
784                         continue;
785
786                 error = gfs2_replay_read_block(jd, start, &bh_log);
787                 if (error)
788                         return error;
789
790                 bh_ip = gfs2_meta_new(gl, blkno);
791                 memcpy(bh_ip->b_data, bh_log->b_data, bh_log->b_size);
792
793                 /* Unescape */
794                 if (esc) {
795                         __be32 *eptr = (__be32 *)bh_ip->b_data;
796                         *eptr = cpu_to_be32(GFS2_MAGIC);
797                 }
798                 mark_buffer_dirty(bh_ip);
799
800                 brelse(bh_log);
801                 brelse(bh_ip);
802
803                 jd->jd_replayed_blocks++;
804         }
805
806         return error;
807 }
808
809 /* FIXME: sort out accounting for log blocks etc. */
810
811 static void databuf_lo_after_scan(struct gfs2_jdesc *jd, int error, int pass)
812 {
813         struct gfs2_inode *ip = GFS2_I(jd->jd_inode);
814         struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
815
816         if (error) {
817                 gfs2_meta_sync(ip->i_gl);
818                 return;
819         }
820         if (pass != 1)
821                 return;
822
823         /* data sync? */
824         gfs2_meta_sync(ip->i_gl);
825
826         fs_info(sdp, "jid=%u: Replayed %u of %u data blocks\n",
827                 jd->jd_jid, jd->jd_replayed_blocks, jd->jd_found_blocks);
828 }
829
830 static void databuf_lo_after_commit(struct gfs2_sbd *sdp, struct gfs2_trans *tr)
831 {
832         struct list_head *head;
833         struct gfs2_bufdata *bd;
834
835         if (tr == NULL)
836                 return;
837
838         head = &tr->tr_databuf;
839         while (!list_empty(head)) {
840                 bd = list_entry(head->next, struct gfs2_bufdata, bd_list);
841                 list_del_init(&bd->bd_list);
842                 gfs2_unpin(sdp, bd->bd_bh, tr);
843         }
844 }
845
846
847 const struct gfs2_log_operations gfs2_buf_lops = {
848         .lo_before_commit = buf_lo_before_commit,
849         .lo_after_commit = buf_lo_after_commit,
850         .lo_before_scan = buf_lo_before_scan,
851         .lo_scan_elements = buf_lo_scan_elements,
852         .lo_after_scan = buf_lo_after_scan,
853         .lo_name = "buf",
854 };
855
856 const struct gfs2_log_operations gfs2_revoke_lops = {
857         .lo_before_commit = revoke_lo_before_commit,
858         .lo_after_commit = revoke_lo_after_commit,
859         .lo_before_scan = revoke_lo_before_scan,
860         .lo_scan_elements = revoke_lo_scan_elements,
861         .lo_after_scan = revoke_lo_after_scan,
862         .lo_name = "revoke",
863 };
864
865 const struct gfs2_log_operations gfs2_databuf_lops = {
866         .lo_before_commit = databuf_lo_before_commit,
867         .lo_after_commit = databuf_lo_after_commit,
868         .lo_scan_elements = databuf_lo_scan_elements,
869         .lo_after_scan = databuf_lo_after_scan,
870         .lo_name = "databuf",
871 };
872
873 const struct gfs2_log_operations *gfs2_log_ops[] = {
874         &gfs2_databuf_lops,
875         &gfs2_buf_lops,
876         &gfs2_revoke_lops,
877         NULL,
878 };
879