Merge git://git.kernel.org/pub/scm/linux/kernel/git/steve/gfs2-3.0-nmw
[~shefty/rdma-dev.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
20 #include "gfs2.h"
21 #include "incore.h"
22 #include "inode.h"
23 #include "glock.h"
24 #include "log.h"
25 #include "lops.h"
26 #include "meta_io.h"
27 #include "recovery.h"
28 #include "rgrp.h"
29 #include "trans.h"
30 #include "util.h"
31 #include "trace_gfs2.h"
32
33 /**
34  * gfs2_pin - Pin a buffer in memory
35  * @sdp: The superblock
36  * @bh: The buffer to be pinned
37  *
38  * The log lock must be held when calling this function
39  */
40 void gfs2_pin(struct gfs2_sbd *sdp, struct buffer_head *bh)
41 {
42         struct gfs2_bufdata *bd;
43
44         BUG_ON(!current->journal_info);
45
46         clear_buffer_dirty(bh);
47         if (test_set_buffer_pinned(bh))
48                 gfs2_assert_withdraw(sdp, 0);
49         if (!buffer_uptodate(bh))
50                 gfs2_io_error_bh(sdp, bh);
51         bd = bh->b_private;
52         /* If this buffer is in the AIL and it has already been written
53          * to in-place disk block, remove it from the AIL.
54          */
55         spin_lock(&sdp->sd_ail_lock);
56         if (bd->bd_ail)
57                 list_move(&bd->bd_ail_st_list, &bd->bd_ail->ai_ail2_list);
58         spin_unlock(&sdp->sd_ail_lock);
59         get_bh(bh);
60         atomic_inc(&sdp->sd_log_pinned);
61         trace_gfs2_pin(bd, 1);
62 }
63
64 static bool buffer_is_rgrp(const struct gfs2_bufdata *bd)
65 {
66         return bd->bd_gl->gl_name.ln_type == LM_TYPE_RGRP;
67 }
68
69 static void maybe_release_space(struct gfs2_bufdata *bd)
70 {
71         struct gfs2_glock *gl = bd->bd_gl;
72         struct gfs2_sbd *sdp = gl->gl_sbd;
73         struct gfs2_rgrpd *rgd = gl->gl_object;
74         unsigned int index = bd->bd_bh->b_blocknr - gl->gl_name.ln_number;
75         struct gfs2_bitmap *bi = rgd->rd_bits + index;
76
77         if (bi->bi_clone == 0)
78                 return;
79         if (sdp->sd_args.ar_discard)
80                 gfs2_rgrp_send_discards(sdp, rgd->rd_data0, bd->bd_bh, bi, 1, NULL);
81         memcpy(bi->bi_clone + bi->bi_offset,
82                bd->bd_bh->b_data + bi->bi_offset, bi->bi_len);
83         clear_bit(GBF_FULL, &bi->bi_flags);
84         rgd->rd_free_clone = rgd->rd_free;
85 }
86
87 /**
88  * gfs2_unpin - Unpin a buffer
89  * @sdp: the filesystem the buffer belongs to
90  * @bh: The buffer to unpin
91  * @ai:
92  * @flags: The inode dirty flags
93  *
94  */
95
96 static void gfs2_unpin(struct gfs2_sbd *sdp, struct buffer_head *bh,
97                        struct gfs2_ail *ai)
98 {
99         struct gfs2_bufdata *bd = bh->b_private;
100
101         BUG_ON(!buffer_uptodate(bh));
102         BUG_ON(!buffer_pinned(bh));
103
104         lock_buffer(bh);
105         mark_buffer_dirty(bh);
106         clear_buffer_pinned(bh);
107
108         if (buffer_is_rgrp(bd))
109                 maybe_release_space(bd);
110
111         spin_lock(&sdp->sd_ail_lock);
112         if (bd->bd_ail) {
113                 list_del(&bd->bd_ail_st_list);
114                 brelse(bh);
115         } else {
116                 struct gfs2_glock *gl = bd->bd_gl;
117                 list_add(&bd->bd_ail_gl_list, &gl->gl_ail_list);
118                 atomic_inc(&gl->gl_ail_count);
119         }
120         bd->bd_ail = ai;
121         list_add(&bd->bd_ail_st_list, &ai->ai_ail1_list);
122         spin_unlock(&sdp->sd_ail_lock);
123
124         clear_bit(GLF_LFLUSH, &bd->bd_gl->gl_flags);
125         trace_gfs2_pin(bd, 0);
126         unlock_buffer(bh);
127         atomic_dec(&sdp->sd_log_pinned);
128 }
129
130 static void gfs2_log_incr_head(struct gfs2_sbd *sdp)
131 {
132         BUG_ON((sdp->sd_log_flush_head == sdp->sd_log_tail) &&
133                (sdp->sd_log_flush_head != sdp->sd_log_head));
134
135         if (++sdp->sd_log_flush_head == sdp->sd_jdesc->jd_blocks) {
136                 sdp->sd_log_flush_head = 0;
137                 sdp->sd_log_flush_wrapped = 1;
138         }
139 }
140
141 static u64 gfs2_log_bmap(struct gfs2_sbd *sdp)
142 {
143         unsigned int lbn = sdp->sd_log_flush_head;
144         struct gfs2_journal_extent *je;
145         u64 block;
146
147         list_for_each_entry(je, &sdp->sd_jdesc->extent_list, extent_list) {
148                 if (lbn >= je->lblock && lbn < je->lblock + je->blocks) {
149                         block = je->dblock + lbn - je->lblock;
150                         gfs2_log_incr_head(sdp);
151                         return block;
152                 }
153         }
154
155         return -1;
156 }
157
158 /**
159  * gfs2_end_log_write_bh - end log write of pagecache data with buffers
160  * @sdp: The superblock
161  * @bvec: The bio_vec
162  * @error: The i/o status
163  *
164  * This finds the relavent buffers and unlocks then and sets the
165  * error flag according to the status of the i/o request. This is
166  * used when the log is writing data which has an in-place version
167  * that is pinned in the pagecache.
168  */
169
170 static void gfs2_end_log_write_bh(struct gfs2_sbd *sdp, struct bio_vec *bvec,
171                                   int error)
172 {
173         struct buffer_head *bh, *next;
174         struct page *page = bvec->bv_page;
175         unsigned size;
176
177         bh = page_buffers(page);
178         size = bvec->bv_len;
179         while (bh_offset(bh) < bvec->bv_offset)
180                 bh = bh->b_this_page;
181         do {
182                 if (error)
183                         set_buffer_write_io_error(bh);
184                 unlock_buffer(bh);
185                 next = bh->b_this_page;
186                 size -= bh->b_size;
187                 brelse(bh);
188                 bh = next;
189         } while(bh && size);
190 }
191
192 /**
193  * gfs2_end_log_write - end of i/o to the log
194  * @bio: The bio
195  * @error: Status of i/o request
196  *
197  * Each bio_vec contains either data from the pagecache or data
198  * relating to the log itself. Here we iterate over the bio_vec
199  * array, processing both kinds of data.
200  *
201  */
202
203 static void gfs2_end_log_write(struct bio *bio, int error)
204 {
205         struct gfs2_sbd *sdp = bio->bi_private;
206         struct bio_vec *bvec;
207         struct page *page;
208         int i;
209
210         if (error) {
211                 sdp->sd_log_error = error;
212                 fs_err(sdp, "Error %d writing to log\n", error);
213         }
214
215         bio_for_each_segment(bvec, bio, i) {
216                 page = bvec->bv_page;
217                 if (page_has_buffers(page))
218                         gfs2_end_log_write_bh(sdp, bvec, error);
219                 else
220                         mempool_free(page, gfs2_page_pool);
221         }
222
223         bio_put(bio);
224         if (atomic_dec_and_test(&sdp->sd_log_in_flight))
225                 wake_up(&sdp->sd_log_flush_wait);
226 }
227
228 /**
229  * gfs2_log_flush_bio - Submit any pending log bio
230  * @sdp: The superblock
231  * @rw: The rw flags
232  *
233  * Submit any pending part-built or full bio to the block device. If
234  * there is no pending bio, then this is a no-op.
235  */
236
237 void gfs2_log_flush_bio(struct gfs2_sbd *sdp, int rw)
238 {
239         if (sdp->sd_log_bio) {
240                 atomic_inc(&sdp->sd_log_in_flight);
241                 submit_bio(rw, sdp->sd_log_bio);
242                 sdp->sd_log_bio = NULL;
243         }
244 }
245
246 /**
247  * gfs2_log_alloc_bio - Allocate a new bio for log writing
248  * @sdp: The superblock
249  * @blkno: The next device block number we want to write to
250  *
251  * This should never be called when there is a cached bio in the
252  * super block. When it returns, there will be a cached bio in the
253  * super block which will have as many bio_vecs as the device is
254  * happy to handle.
255  *
256  * Returns: Newly allocated bio
257  */
258
259 static struct bio *gfs2_log_alloc_bio(struct gfs2_sbd *sdp, u64 blkno)
260 {
261         struct super_block *sb = sdp->sd_vfs;
262         unsigned nrvecs = bio_get_nr_vecs(sb->s_bdev);
263         struct bio *bio;
264
265         BUG_ON(sdp->sd_log_bio);
266
267         while (1) {
268                 bio = bio_alloc(GFP_NOIO, nrvecs);
269                 if (likely(bio))
270                         break;
271                 nrvecs = max(nrvecs/2, 1U);
272         }
273
274         bio->bi_sector = blkno * (sb->s_blocksize >> 9);
275         bio->bi_bdev = sb->s_bdev;
276         bio->bi_end_io = gfs2_end_log_write;
277         bio->bi_private = sdp;
278
279         sdp->sd_log_bio = bio;
280
281         return bio;
282 }
283
284 /**
285  * gfs2_log_get_bio - Get cached log bio, or allocate a new one
286  * @sdp: The superblock
287  * @blkno: The device block number we want to write to
288  *
289  * If there is a cached bio, then if the next block number is sequential
290  * with the previous one, return it, otherwise flush the bio to the
291  * device. If there is not a cached bio, or we just flushed it, then
292  * allocate a new one.
293  *
294  * Returns: The bio to use for log writes
295  */
296
297 static struct bio *gfs2_log_get_bio(struct gfs2_sbd *sdp, u64 blkno)
298 {
299         struct bio *bio = sdp->sd_log_bio;
300         u64 nblk;
301
302         if (bio) {
303                 nblk = bio->bi_sector + bio_sectors(bio);
304                 nblk >>= sdp->sd_fsb2bb_shift;
305                 if (blkno == nblk)
306                         return bio;
307                 gfs2_log_flush_bio(sdp, WRITE);
308         }
309
310         return gfs2_log_alloc_bio(sdp, blkno);
311 }
312
313
314 /**
315  * gfs2_log_write - write to log
316  * @sdp: the filesystem
317  * @page: the page to write
318  * @size: the size of the data to write
319  * @offset: the offset within the page 
320  *
321  * Try and add the page segment to the current bio. If that fails,
322  * submit the current bio to the device and create a new one, and
323  * then add the page segment to that.
324  */
325
326 static void gfs2_log_write(struct gfs2_sbd *sdp, struct page *page,
327                            unsigned size, unsigned offset)
328 {
329         u64 blkno = gfs2_log_bmap(sdp);
330         struct bio *bio;
331         int ret;
332
333         bio = gfs2_log_get_bio(sdp, blkno);
334         ret = bio_add_page(bio, page, size, offset);
335         if (ret == 0) {
336                 gfs2_log_flush_bio(sdp, WRITE);
337                 bio = gfs2_log_alloc_bio(sdp, blkno);
338                 ret = bio_add_page(bio, page, size, offset);
339                 WARN_ON(ret == 0);
340         }
341 }
342
343 /**
344  * gfs2_log_write_bh - write a buffer's content to the log
345  * @sdp: The super block
346  * @bh: The buffer pointing to the in-place location
347  * 
348  * This writes the content of the buffer to the next available location
349  * in the log. The buffer will be unlocked once the i/o to the log has
350  * completed.
351  */
352
353 static void gfs2_log_write_bh(struct gfs2_sbd *sdp, struct buffer_head *bh)
354 {
355         gfs2_log_write(sdp, bh->b_page, bh->b_size, bh_offset(bh));
356 }
357
358 /**
359  * gfs2_log_write_page - write one block stored in a page, into the log
360  * @sdp: The superblock
361  * @page: The struct page
362  *
363  * This writes the first block-sized part of the page into the log. Note
364  * that the page must have been allocated from the gfs2_page_pool mempool
365  * and that after this has been called, ownership has been transferred and
366  * the page may be freed at any time.
367  */
368
369 void gfs2_log_write_page(struct gfs2_sbd *sdp, struct page *page)
370 {
371         struct super_block *sb = sdp->sd_vfs;
372         gfs2_log_write(sdp, page, sb->s_blocksize, 0);
373 }
374
375 static struct page *gfs2_get_log_desc(struct gfs2_sbd *sdp, u32 ld_type,
376                                       u32 ld_length, u32 ld_data1)
377 {
378         struct page *page = mempool_alloc(gfs2_page_pool, GFP_NOIO);
379         struct gfs2_log_descriptor *ld = page_address(page);
380         clear_page(ld);
381         ld->ld_header.mh_magic = cpu_to_be32(GFS2_MAGIC);
382         ld->ld_header.mh_type = cpu_to_be32(GFS2_METATYPE_LD);
383         ld->ld_header.mh_format = cpu_to_be32(GFS2_FORMAT_LD);
384         ld->ld_type = cpu_to_be32(ld_type);
385         ld->ld_length = cpu_to_be32(ld_length);
386         ld->ld_data1 = cpu_to_be32(ld_data1);
387         ld->ld_data2 = 0;
388         return page;
389 }
390
391 static void gfs2_check_magic(struct buffer_head *bh)
392 {
393         void *kaddr;
394         __be32 *ptr;
395
396         clear_buffer_escaped(bh);
397         kaddr = kmap_atomic(bh->b_page);
398         ptr = kaddr + bh_offset(bh);
399         if (*ptr == cpu_to_be32(GFS2_MAGIC))
400                 set_buffer_escaped(bh);
401         kunmap_atomic(kaddr);
402 }
403
404 static void gfs2_before_commit(struct gfs2_sbd *sdp, unsigned int limit,
405                                 unsigned int total, struct list_head *blist,
406                                 bool is_databuf)
407 {
408         struct gfs2_log_descriptor *ld;
409         struct gfs2_bufdata *bd1 = NULL, *bd2;
410         struct page *page;
411         unsigned int num;
412         unsigned n;
413         __be64 *ptr;
414
415         gfs2_log_lock(sdp);
416         bd1 = bd2 = list_prepare_entry(bd1, blist, bd_list);
417         while(total) {
418                 num = total;
419                 if (total > limit)
420                         num = limit;
421                 gfs2_log_unlock(sdp);
422                 page = gfs2_get_log_desc(sdp, GFS2_LOG_DESC_METADATA, num + 1, num);
423                 ld = page_address(page);
424                 gfs2_log_lock(sdp);
425                 ptr = (__be64 *)(ld + 1);
426
427                 n = 0;
428                 list_for_each_entry_continue(bd1, blist, bd_list) {
429                         *ptr++ = cpu_to_be64(bd1->bd_bh->b_blocknr);
430                         if (is_databuf) {
431                                 gfs2_check_magic(bd1->bd_bh);
432                                 *ptr++ = cpu_to_be64(buffer_escaped(bd1->bd_bh) ? 1 : 0);
433                         }
434                         if (++n >= num)
435                                 break;
436                 }
437
438                 gfs2_log_unlock(sdp);
439                 gfs2_log_write_page(sdp, page);
440                 gfs2_log_lock(sdp);
441
442                 n = 0;
443                 list_for_each_entry_continue(bd2, blist, bd_list) {
444                         get_bh(bd2->bd_bh);
445                         gfs2_log_unlock(sdp);
446                         lock_buffer(bd2->bd_bh);
447
448                         if (buffer_escaped(bd2->bd_bh)) {
449                                 void *kaddr;
450                                 page = mempool_alloc(gfs2_page_pool, GFP_NOIO);
451                                 ptr = page_address(page);
452                                 kaddr = kmap_atomic(bd2->bd_bh->b_page);
453                                 memcpy(ptr, kaddr + bh_offset(bd2->bd_bh),
454                                        bd2->bd_bh->b_size);
455                                 kunmap_atomic(kaddr);
456                                 *(__be32 *)ptr = 0;
457                                 clear_buffer_escaped(bd2->bd_bh);
458                                 unlock_buffer(bd2->bd_bh);
459                                 brelse(bd2->bd_bh);
460                                 gfs2_log_write_page(sdp, page);
461                         } else {
462                                 gfs2_log_write_bh(sdp, bd2->bd_bh);
463                         }
464                         gfs2_log_lock(sdp);
465                         if (++n >= num)
466                                 break;
467                 }
468
469                 BUG_ON(total < num);
470                 total -= num;
471         }
472         gfs2_log_unlock(sdp);
473 }
474
475 static void buf_lo_before_commit(struct gfs2_sbd *sdp)
476 {
477         unsigned int limit = buf_limit(sdp); /* 503 for 4k blocks */
478
479         gfs2_before_commit(sdp, limit, sdp->sd_log_num_buf,
480                            &sdp->sd_log_le_buf, 0);
481 }
482
483 static void buf_lo_after_commit(struct gfs2_sbd *sdp, struct gfs2_ail *ai)
484 {
485         struct list_head *head = &sdp->sd_log_le_buf;
486         struct gfs2_bufdata *bd;
487
488         while (!list_empty(head)) {
489                 bd = list_entry(head->next, struct gfs2_bufdata, bd_list);
490                 list_del_init(&bd->bd_list);
491                 sdp->sd_log_num_buf--;
492
493                 gfs2_unpin(sdp, bd->bd_bh, ai);
494         }
495         gfs2_assert_warn(sdp, !sdp->sd_log_num_buf);
496 }
497
498 static void buf_lo_before_scan(struct gfs2_jdesc *jd,
499                                struct gfs2_log_header_host *head, int pass)
500 {
501         struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
502
503         if (pass != 0)
504                 return;
505
506         sdp->sd_found_blocks = 0;
507         sdp->sd_replayed_blocks = 0;
508 }
509
510 static int buf_lo_scan_elements(struct gfs2_jdesc *jd, unsigned int start,
511                                 struct gfs2_log_descriptor *ld, __be64 *ptr,
512                                 int pass)
513 {
514         struct gfs2_inode *ip = GFS2_I(jd->jd_inode);
515         struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
516         struct gfs2_glock *gl = ip->i_gl;
517         unsigned int blks = be32_to_cpu(ld->ld_data1);
518         struct buffer_head *bh_log, *bh_ip;
519         u64 blkno;
520         int error = 0;
521
522         if (pass != 1 || be32_to_cpu(ld->ld_type) != GFS2_LOG_DESC_METADATA)
523                 return 0;
524
525         gfs2_replay_incr_blk(sdp, &start);
526
527         for (; blks; gfs2_replay_incr_blk(sdp, &start), blks--) {
528                 blkno = be64_to_cpu(*ptr++);
529
530                 sdp->sd_found_blocks++;
531
532                 if (gfs2_revoke_check(sdp, blkno, start))
533                         continue;
534
535                 error = gfs2_replay_read_block(jd, start, &bh_log);
536                 if (error)
537                         return error;
538
539                 bh_ip = gfs2_meta_new(gl, blkno);
540                 memcpy(bh_ip->b_data, bh_log->b_data, bh_log->b_size);
541
542                 if (gfs2_meta_check(sdp, bh_ip))
543                         error = -EIO;
544                 else
545                         mark_buffer_dirty(bh_ip);
546
547                 brelse(bh_log);
548                 brelse(bh_ip);
549
550                 if (error)
551                         break;
552
553                 sdp->sd_replayed_blocks++;
554         }
555
556         return error;
557 }
558
559 static void buf_lo_after_scan(struct gfs2_jdesc *jd, int error, int pass)
560 {
561         struct gfs2_inode *ip = GFS2_I(jd->jd_inode);
562         struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
563
564         if (error) {
565                 gfs2_meta_sync(ip->i_gl);
566                 return;
567         }
568         if (pass != 1)
569                 return;
570
571         gfs2_meta_sync(ip->i_gl);
572
573         fs_info(sdp, "jid=%u: Replayed %u of %u blocks\n",
574                 jd->jd_jid, sdp->sd_replayed_blocks, sdp->sd_found_blocks);
575 }
576
577 static void revoke_lo_before_commit(struct gfs2_sbd *sdp)
578 {
579         struct gfs2_meta_header *mh;
580         unsigned int offset;
581         struct list_head *head = &sdp->sd_log_le_revoke;
582         struct gfs2_bufdata *bd;
583         struct page *page;
584         unsigned int length;
585
586         if (!sdp->sd_log_num_revoke)
587                 return;
588
589         length = gfs2_struct2blk(sdp, sdp->sd_log_num_revoke, sizeof(u64));
590         page = gfs2_get_log_desc(sdp, GFS2_LOG_DESC_REVOKE, length, sdp->sd_log_num_revoke);
591         offset = sizeof(struct gfs2_log_descriptor);
592
593         list_for_each_entry(bd, head, bd_list) {
594                 sdp->sd_log_num_revoke--;
595
596                 if (offset + sizeof(u64) > sdp->sd_sb.sb_bsize) {
597
598                         gfs2_log_write_page(sdp, page);
599                         page = mempool_alloc(gfs2_page_pool, GFP_NOIO);
600                         mh = page_address(page);
601                         clear_page(mh);
602                         mh->mh_magic = cpu_to_be32(GFS2_MAGIC);
603                         mh->mh_type = cpu_to_be32(GFS2_METATYPE_LB);
604                         mh->mh_format = cpu_to_be32(GFS2_FORMAT_LB);
605                         offset = sizeof(struct gfs2_meta_header);
606                 }
607
608                 *(__be64 *)(page_address(page) + offset) = cpu_to_be64(bd->bd_blkno);
609                 offset += sizeof(u64);
610         }
611         gfs2_assert_withdraw(sdp, !sdp->sd_log_num_revoke);
612
613         gfs2_log_write_page(sdp, page);
614 }
615
616 static void revoke_lo_after_commit(struct gfs2_sbd *sdp, struct gfs2_ail *ai)
617 {
618         struct list_head *head = &sdp->sd_log_le_revoke;
619         struct gfs2_bufdata *bd;
620         struct gfs2_glock *gl;
621
622         while (!list_empty(head)) {
623                 bd = list_entry(head->next, struct gfs2_bufdata, bd_list);
624                 list_del_init(&bd->bd_list);
625                 gl = bd->bd_gl;
626                 atomic_dec(&gl->gl_revokes);
627                 clear_bit(GLF_LFLUSH, &gl->gl_flags);
628                 kmem_cache_free(gfs2_bufdata_cachep, bd);
629         }
630 }
631
632 static void revoke_lo_before_scan(struct gfs2_jdesc *jd,
633                                   struct gfs2_log_header_host *head, int pass)
634 {
635         struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
636
637         if (pass != 0)
638                 return;
639
640         sdp->sd_found_revokes = 0;
641         sdp->sd_replay_tail = head->lh_tail;
642 }
643
644 static int revoke_lo_scan_elements(struct gfs2_jdesc *jd, unsigned int start,
645                                    struct gfs2_log_descriptor *ld, __be64 *ptr,
646                                    int pass)
647 {
648         struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
649         unsigned int blks = be32_to_cpu(ld->ld_length);
650         unsigned int revokes = be32_to_cpu(ld->ld_data1);
651         struct buffer_head *bh;
652         unsigned int offset;
653         u64 blkno;
654         int first = 1;
655         int error;
656
657         if (pass != 0 || be32_to_cpu(ld->ld_type) != GFS2_LOG_DESC_REVOKE)
658                 return 0;
659
660         offset = sizeof(struct gfs2_log_descriptor);
661
662         for (; blks; gfs2_replay_incr_blk(sdp, &start), blks--) {
663                 error = gfs2_replay_read_block(jd, start, &bh);
664                 if (error)
665                         return error;
666
667                 if (!first)
668                         gfs2_metatype_check(sdp, bh, GFS2_METATYPE_LB);
669
670                 while (offset + sizeof(u64) <= sdp->sd_sb.sb_bsize) {
671                         blkno = be64_to_cpu(*(__be64 *)(bh->b_data + offset));
672
673                         error = gfs2_revoke_add(sdp, blkno, start);
674                         if (error < 0) {
675                                 brelse(bh);
676                                 return error;
677                         }
678                         else if (error)
679                                 sdp->sd_found_revokes++;
680
681                         if (!--revokes)
682                                 break;
683                         offset += sizeof(u64);
684                 }
685
686                 brelse(bh);
687                 offset = sizeof(struct gfs2_meta_header);
688                 first = 0;
689         }
690
691         return 0;
692 }
693
694 static void revoke_lo_after_scan(struct gfs2_jdesc *jd, int error, int pass)
695 {
696         struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
697
698         if (error) {
699                 gfs2_revoke_clean(sdp);
700                 return;
701         }
702         if (pass != 1)
703                 return;
704
705         fs_info(sdp, "jid=%u: Found %u revoke tags\n",
706                 jd->jd_jid, sdp->sd_found_revokes);
707
708         gfs2_revoke_clean(sdp);
709 }
710
711 /**
712  * databuf_lo_before_commit - Scan the data buffers, writing as we go
713  *
714  */
715
716 static void databuf_lo_before_commit(struct gfs2_sbd *sdp)
717 {
718         unsigned int limit = buf_limit(sdp) / 2;
719
720         gfs2_before_commit(sdp, limit, sdp->sd_log_num_databuf,
721                            &sdp->sd_log_le_databuf, 1);
722 }
723
724 static int databuf_lo_scan_elements(struct gfs2_jdesc *jd, unsigned int start,
725                                     struct gfs2_log_descriptor *ld,
726                                     __be64 *ptr, int pass)
727 {
728         struct gfs2_inode *ip = GFS2_I(jd->jd_inode);
729         struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
730         struct gfs2_glock *gl = ip->i_gl;
731         unsigned int blks = be32_to_cpu(ld->ld_data1);
732         struct buffer_head *bh_log, *bh_ip;
733         u64 blkno;
734         u64 esc;
735         int error = 0;
736
737         if (pass != 1 || be32_to_cpu(ld->ld_type) != GFS2_LOG_DESC_JDATA)
738                 return 0;
739
740         gfs2_replay_incr_blk(sdp, &start);
741         for (; blks; gfs2_replay_incr_blk(sdp, &start), blks--) {
742                 blkno = be64_to_cpu(*ptr++);
743                 esc = be64_to_cpu(*ptr++);
744
745                 sdp->sd_found_blocks++;
746
747                 if (gfs2_revoke_check(sdp, blkno, start))
748                         continue;
749
750                 error = gfs2_replay_read_block(jd, start, &bh_log);
751                 if (error)
752                         return error;
753
754                 bh_ip = gfs2_meta_new(gl, blkno);
755                 memcpy(bh_ip->b_data, bh_log->b_data, bh_log->b_size);
756
757                 /* Unescape */
758                 if (esc) {
759                         __be32 *eptr = (__be32 *)bh_ip->b_data;
760                         *eptr = cpu_to_be32(GFS2_MAGIC);
761                 }
762                 mark_buffer_dirty(bh_ip);
763
764                 brelse(bh_log);
765                 brelse(bh_ip);
766
767                 sdp->sd_replayed_blocks++;
768         }
769
770         return error;
771 }
772
773 /* FIXME: sort out accounting for log blocks etc. */
774
775 static void databuf_lo_after_scan(struct gfs2_jdesc *jd, int error, int pass)
776 {
777         struct gfs2_inode *ip = GFS2_I(jd->jd_inode);
778         struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
779
780         if (error) {
781                 gfs2_meta_sync(ip->i_gl);
782                 return;
783         }
784         if (pass != 1)
785                 return;
786
787         /* data sync? */
788         gfs2_meta_sync(ip->i_gl);
789
790         fs_info(sdp, "jid=%u: Replayed %u of %u data blocks\n",
791                 jd->jd_jid, sdp->sd_replayed_blocks, sdp->sd_found_blocks);
792 }
793
794 static void databuf_lo_after_commit(struct gfs2_sbd *sdp, struct gfs2_ail *ai)
795 {
796         struct list_head *head = &sdp->sd_log_le_databuf;
797         struct gfs2_bufdata *bd;
798
799         while (!list_empty(head)) {
800                 bd = list_entry(head->next, struct gfs2_bufdata, bd_list);
801                 list_del_init(&bd->bd_list);
802                 sdp->sd_log_num_databuf--;
803                 gfs2_unpin(sdp, bd->bd_bh, ai);
804         }
805         gfs2_assert_warn(sdp, !sdp->sd_log_num_databuf);
806 }
807
808
809 const struct gfs2_log_operations gfs2_buf_lops = {
810         .lo_before_commit = buf_lo_before_commit,
811         .lo_after_commit = buf_lo_after_commit,
812         .lo_before_scan = buf_lo_before_scan,
813         .lo_scan_elements = buf_lo_scan_elements,
814         .lo_after_scan = buf_lo_after_scan,
815         .lo_name = "buf",
816 };
817
818 const struct gfs2_log_operations gfs2_revoke_lops = {
819         .lo_before_commit = revoke_lo_before_commit,
820         .lo_after_commit = revoke_lo_after_commit,
821         .lo_before_scan = revoke_lo_before_scan,
822         .lo_scan_elements = revoke_lo_scan_elements,
823         .lo_after_scan = revoke_lo_after_scan,
824         .lo_name = "revoke",
825 };
826
827 const struct gfs2_log_operations gfs2_rg_lops = {
828         .lo_name = "rg",
829 };
830
831 const struct gfs2_log_operations gfs2_databuf_lops = {
832         .lo_before_commit = databuf_lo_before_commit,
833         .lo_after_commit = databuf_lo_after_commit,
834         .lo_scan_elements = databuf_lo_scan_elements,
835         .lo_after_scan = databuf_lo_after_scan,
836         .lo_name = "databuf",
837 };
838
839 const struct gfs2_log_operations *gfs2_log_ops[] = {
840         &gfs2_databuf_lops,
841         &gfs2_buf_lops,
842         &gfs2_rg_lops,
843         &gfs2_revoke_lops,
844         NULL,
845 };
846