xref: /openbmc/linux/fs/gfs2/lops.c (revision c969f58c)
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/bio.h>
17 #include <linux/fs.h>
18 
19 #include "gfs2.h"
20 #include "incore.h"
21 #include "inode.h"
22 #include "glock.h"
23 #include "log.h"
24 #include "lops.h"
25 #include "meta_io.h"
26 #include "recovery.h"
27 #include "rgrp.h"
28 #include "trans.h"
29 #include "util.h"
30 
31 /**
32  * gfs2_pin - Pin a buffer in memory
33  * @sdp: The superblock
34  * @bh: The buffer to be pinned
35  *
36  * The log lock must be held when calling this function
37  */
38 static void gfs2_pin(struct gfs2_sbd *sdp, struct buffer_head *bh)
39 {
40 	struct gfs2_bufdata *bd;
41 
42 	gfs2_assert_withdraw(sdp, test_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags));
43 
44 	clear_buffer_dirty(bh);
45 	if (test_set_buffer_pinned(bh))
46 		gfs2_assert_withdraw(sdp, 0);
47 	if (!buffer_uptodate(bh))
48 		gfs2_io_error_bh(sdp, bh);
49 	bd = bh->b_private;
50 	/* If this buffer is in the AIL and it has already been written
51 	 * to in-place disk block, remove it from the AIL.
52 	 */
53 	if (bd->bd_ail)
54 		list_move(&bd->bd_ail_st_list, &bd->bd_ail->ai_ail2_list);
55 	get_bh(bh);
56 }
57 
58 /**
59  * gfs2_unpin - Unpin a buffer
60  * @sdp: the filesystem the buffer belongs to
61  * @bh: The buffer to unpin
62  * @ai:
63  *
64  */
65 
66 static void gfs2_unpin(struct gfs2_sbd *sdp, struct buffer_head *bh,
67 		       struct gfs2_ail *ai)
68 {
69 	struct gfs2_bufdata *bd = bh->b_private;
70 
71 	gfs2_assert_withdraw(sdp, buffer_uptodate(bh));
72 
73 	if (!buffer_pinned(bh))
74 		gfs2_assert_withdraw(sdp, 0);
75 
76 	lock_buffer(bh);
77 	mark_buffer_dirty(bh);
78 	clear_buffer_pinned(bh);
79 
80 	gfs2_log_lock(sdp);
81 	if (bd->bd_ail) {
82 		list_del(&bd->bd_ail_st_list);
83 		brelse(bh);
84 	} else {
85 		struct gfs2_glock *gl = bd->bd_gl;
86 		list_add(&bd->bd_ail_gl_list, &gl->gl_ail_list);
87 		atomic_inc(&gl->gl_ail_count);
88 	}
89 	bd->bd_ail = ai;
90 	list_add(&bd->bd_ail_st_list, &ai->ai_ail1_list);
91 	clear_bit(GLF_LFLUSH, &bd->bd_gl->gl_flags);
92 	gfs2_log_unlock(sdp);
93 	unlock_buffer(bh);
94 }
95 
96 
97 static inline struct gfs2_log_descriptor *bh_log_desc(struct buffer_head *bh)
98 {
99 	return (struct gfs2_log_descriptor *)bh->b_data;
100 }
101 
102 static inline __be64 *bh_log_ptr(struct buffer_head *bh)
103 {
104 	struct gfs2_log_descriptor *ld = bh_log_desc(bh);
105 	return (__force __be64 *)(ld + 1);
106 }
107 
108 static inline __be64 *bh_ptr_end(struct buffer_head *bh)
109 {
110 	return (__force __be64 *)(bh->b_data + bh->b_size);
111 }
112 
113 
114 static struct buffer_head *gfs2_get_log_desc(struct gfs2_sbd *sdp, u32 ld_type)
115 {
116 	struct buffer_head *bh = gfs2_log_get_buf(sdp);
117 	struct gfs2_log_descriptor *ld = bh_log_desc(bh);
118 	ld->ld_header.mh_magic = cpu_to_be32(GFS2_MAGIC);
119 	ld->ld_header.mh_type = cpu_to_be32(GFS2_METATYPE_LD);
120 	ld->ld_header.mh_format = cpu_to_be32(GFS2_FORMAT_LD);
121 	ld->ld_type = cpu_to_be32(ld_type);
122 	ld->ld_length = 0;
123 	ld->ld_data1 = 0;
124 	ld->ld_data2 = 0;
125 	memset(ld->ld_reserved, 0, sizeof(ld->ld_reserved));
126 	return bh;
127 }
128 
129 static void buf_lo_add(struct gfs2_sbd *sdp, struct gfs2_log_element *le)
130 {
131 	struct gfs2_bufdata *bd = container_of(le, struct gfs2_bufdata, bd_le);
132 	struct gfs2_trans *tr;
133 
134 	lock_buffer(bd->bd_bh);
135 	gfs2_log_lock(sdp);
136 	if (!list_empty(&bd->bd_list_tr))
137 		goto out;
138 	tr = current->journal_info;
139 	tr->tr_touched = 1;
140 	tr->tr_num_buf++;
141 	list_add(&bd->bd_list_tr, &tr->tr_list_buf);
142 	if (!list_empty(&le->le_list))
143 		goto out;
144 	set_bit(GLF_LFLUSH, &bd->bd_gl->gl_flags);
145 	set_bit(GLF_DIRTY, &bd->bd_gl->gl_flags);
146 	gfs2_meta_check(sdp, bd->bd_bh);
147 	gfs2_pin(sdp, bd->bd_bh);
148 	sdp->sd_log_num_buf++;
149 	list_add(&le->le_list, &sdp->sd_log_le_buf);
150 	tr->tr_num_buf_new++;
151 out:
152 	gfs2_log_unlock(sdp);
153 	unlock_buffer(bd->bd_bh);
154 }
155 
156 static void buf_lo_before_commit(struct gfs2_sbd *sdp)
157 {
158 	struct buffer_head *bh;
159 	struct gfs2_log_descriptor *ld;
160 	struct gfs2_bufdata *bd1 = NULL, *bd2;
161 	unsigned int total;
162 	unsigned int limit;
163 	unsigned int num;
164 	unsigned n;
165 	__be64 *ptr;
166 
167 	limit = buf_limit(sdp);
168 	/* for 4k blocks, limit = 503 */
169 
170 	gfs2_log_lock(sdp);
171 	total = sdp->sd_log_num_buf;
172 	bd1 = bd2 = list_prepare_entry(bd1, &sdp->sd_log_le_buf, bd_le.le_list);
173 	while(total) {
174 		num = total;
175 		if (total > limit)
176 			num = limit;
177 		gfs2_log_unlock(sdp);
178 		bh = gfs2_get_log_desc(sdp, GFS2_LOG_DESC_METADATA);
179 		gfs2_log_lock(sdp);
180 		ld = bh_log_desc(bh);
181 		ptr = bh_log_ptr(bh);
182 		ld->ld_length = cpu_to_be32(num + 1);
183 		ld->ld_data1 = cpu_to_be32(num);
184 
185 		n = 0;
186 		list_for_each_entry_continue(bd1, &sdp->sd_log_le_buf,
187 					     bd_le.le_list) {
188 			*ptr++ = cpu_to_be64(bd1->bd_bh->b_blocknr);
189 			if (++n >= num)
190 				break;
191 		}
192 
193 		gfs2_log_unlock(sdp);
194 		submit_bh(WRITE_SYNC_PLUG, bh);
195 		gfs2_log_lock(sdp);
196 
197 		n = 0;
198 		list_for_each_entry_continue(bd2, &sdp->sd_log_le_buf,
199 					     bd_le.le_list) {
200 			get_bh(bd2->bd_bh);
201 			gfs2_log_unlock(sdp);
202 			lock_buffer(bd2->bd_bh);
203 			bh = gfs2_log_fake_buf(sdp, bd2->bd_bh);
204 			submit_bh(WRITE_SYNC_PLUG, bh);
205 			gfs2_log_lock(sdp);
206 			if (++n >= num)
207 				break;
208 		}
209 
210 		BUG_ON(total < num);
211 		total -= num;
212 	}
213 	gfs2_log_unlock(sdp);
214 }
215 
216 static void buf_lo_after_commit(struct gfs2_sbd *sdp, struct gfs2_ail *ai)
217 {
218 	struct list_head *head = &sdp->sd_log_le_buf;
219 	struct gfs2_bufdata *bd;
220 
221 	while (!list_empty(head)) {
222 		bd = list_entry(head->next, struct gfs2_bufdata, bd_le.le_list);
223 		list_del_init(&bd->bd_le.le_list);
224 		sdp->sd_log_num_buf--;
225 
226 		gfs2_unpin(sdp, bd->bd_bh, ai);
227 	}
228 	gfs2_assert_warn(sdp, !sdp->sd_log_num_buf);
229 }
230 
231 static void buf_lo_before_scan(struct gfs2_jdesc *jd,
232 			       struct gfs2_log_header_host *head, int pass)
233 {
234 	struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
235 
236 	if (pass != 0)
237 		return;
238 
239 	sdp->sd_found_blocks = 0;
240 	sdp->sd_replayed_blocks = 0;
241 }
242 
243 static int buf_lo_scan_elements(struct gfs2_jdesc *jd, unsigned int start,
244 				struct gfs2_log_descriptor *ld, __be64 *ptr,
245 				int pass)
246 {
247 	struct gfs2_inode *ip = GFS2_I(jd->jd_inode);
248 	struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
249 	struct gfs2_glock *gl = ip->i_gl;
250 	unsigned int blks = be32_to_cpu(ld->ld_data1);
251 	struct buffer_head *bh_log, *bh_ip;
252 	u64 blkno;
253 	int error = 0;
254 
255 	if (pass != 1 || be32_to_cpu(ld->ld_type) != GFS2_LOG_DESC_METADATA)
256 		return 0;
257 
258 	gfs2_replay_incr_blk(sdp, &start);
259 
260 	for (; blks; gfs2_replay_incr_blk(sdp, &start), blks--) {
261 		blkno = be64_to_cpu(*ptr++);
262 
263 		sdp->sd_found_blocks++;
264 
265 		if (gfs2_revoke_check(sdp, blkno, start))
266 			continue;
267 
268 		error = gfs2_replay_read_block(jd, start, &bh_log);
269 		if (error)
270 			return error;
271 
272 		bh_ip = gfs2_meta_new(gl, blkno);
273 		memcpy(bh_ip->b_data, bh_log->b_data, bh_log->b_size);
274 
275 		if (gfs2_meta_check(sdp, bh_ip))
276 			error = -EIO;
277 		else
278 			mark_buffer_dirty(bh_ip);
279 
280 		brelse(bh_log);
281 		brelse(bh_ip);
282 
283 		if (error)
284 			break;
285 
286 		sdp->sd_replayed_blocks++;
287 	}
288 
289 	return error;
290 }
291 
292 static void buf_lo_after_scan(struct gfs2_jdesc *jd, int error, int pass)
293 {
294 	struct gfs2_inode *ip = GFS2_I(jd->jd_inode);
295 	struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
296 
297 	if (error) {
298 		gfs2_meta_sync(ip->i_gl);
299 		return;
300 	}
301 	if (pass != 1)
302 		return;
303 
304 	gfs2_meta_sync(ip->i_gl);
305 
306 	fs_info(sdp, "jid=%u: Replayed %u of %u blocks\n",
307 	        jd->jd_jid, sdp->sd_replayed_blocks, sdp->sd_found_blocks);
308 }
309 
310 static void revoke_lo_add(struct gfs2_sbd *sdp, struct gfs2_log_element *le)
311 {
312 	struct gfs2_trans *tr;
313 
314 	tr = current->journal_info;
315 	tr->tr_touched = 1;
316 	tr->tr_num_revoke++;
317 	sdp->sd_log_num_revoke++;
318 	list_add(&le->le_list, &sdp->sd_log_le_revoke);
319 }
320 
321 static void revoke_lo_before_commit(struct gfs2_sbd *sdp)
322 {
323 	struct gfs2_log_descriptor *ld;
324 	struct gfs2_meta_header *mh;
325 	struct buffer_head *bh;
326 	unsigned int offset;
327 	struct list_head *head = &sdp->sd_log_le_revoke;
328 	struct gfs2_bufdata *bd;
329 
330 	if (!sdp->sd_log_num_revoke)
331 		return;
332 
333 	bh = gfs2_get_log_desc(sdp, GFS2_LOG_DESC_REVOKE);
334 	ld = bh_log_desc(bh);
335 	ld->ld_length = cpu_to_be32(gfs2_struct2blk(sdp, sdp->sd_log_num_revoke,
336 						    sizeof(u64)));
337 	ld->ld_data1 = cpu_to_be32(sdp->sd_log_num_revoke);
338 	offset = sizeof(struct gfs2_log_descriptor);
339 
340 	while (!list_empty(head)) {
341 		bd = list_entry(head->next, struct gfs2_bufdata, bd_le.le_list);
342 		list_del_init(&bd->bd_le.le_list);
343 		sdp->sd_log_num_revoke--;
344 
345 		if (offset + sizeof(u64) > sdp->sd_sb.sb_bsize) {
346 			submit_bh(WRITE_SYNC_PLUG, bh);
347 
348 			bh = gfs2_log_get_buf(sdp);
349 			mh = (struct gfs2_meta_header *)bh->b_data;
350 			mh->mh_magic = cpu_to_be32(GFS2_MAGIC);
351 			mh->mh_type = cpu_to_be32(GFS2_METATYPE_LB);
352 			mh->mh_format = cpu_to_be32(GFS2_FORMAT_LB);
353 			offset = sizeof(struct gfs2_meta_header);
354 		}
355 
356 		*(__be64 *)(bh->b_data + offset) = cpu_to_be64(bd->bd_blkno);
357 		kmem_cache_free(gfs2_bufdata_cachep, bd);
358 
359 		offset += sizeof(u64);
360 	}
361 	gfs2_assert_withdraw(sdp, !sdp->sd_log_num_revoke);
362 
363 	submit_bh(WRITE_SYNC_PLUG, bh);
364 }
365 
366 static void revoke_lo_before_scan(struct gfs2_jdesc *jd,
367 				  struct gfs2_log_header_host *head, int pass)
368 {
369 	struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
370 
371 	if (pass != 0)
372 		return;
373 
374 	sdp->sd_found_revokes = 0;
375 	sdp->sd_replay_tail = head->lh_tail;
376 }
377 
378 static int revoke_lo_scan_elements(struct gfs2_jdesc *jd, unsigned int start,
379 				   struct gfs2_log_descriptor *ld, __be64 *ptr,
380 				   int pass)
381 {
382 	struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
383 	unsigned int blks = be32_to_cpu(ld->ld_length);
384 	unsigned int revokes = be32_to_cpu(ld->ld_data1);
385 	struct buffer_head *bh;
386 	unsigned int offset;
387 	u64 blkno;
388 	int first = 1;
389 	int error;
390 
391 	if (pass != 0 || be32_to_cpu(ld->ld_type) != GFS2_LOG_DESC_REVOKE)
392 		return 0;
393 
394 	offset = sizeof(struct gfs2_log_descriptor);
395 
396 	for (; blks; gfs2_replay_incr_blk(sdp, &start), blks--) {
397 		error = gfs2_replay_read_block(jd, start, &bh);
398 		if (error)
399 			return error;
400 
401 		if (!first)
402 			gfs2_metatype_check(sdp, bh, GFS2_METATYPE_LB);
403 
404 		while (offset + sizeof(u64) <= sdp->sd_sb.sb_bsize) {
405 			blkno = be64_to_cpu(*(__be64 *)(bh->b_data + offset));
406 
407 			error = gfs2_revoke_add(sdp, blkno, start);
408 			if (error < 0) {
409 				brelse(bh);
410 				return error;
411 			}
412 			else if (error)
413 				sdp->sd_found_revokes++;
414 
415 			if (!--revokes)
416 				break;
417 			offset += sizeof(u64);
418 		}
419 
420 		brelse(bh);
421 		offset = sizeof(struct gfs2_meta_header);
422 		first = 0;
423 	}
424 
425 	return 0;
426 }
427 
428 static void revoke_lo_after_scan(struct gfs2_jdesc *jd, int error, int pass)
429 {
430 	struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
431 
432 	if (error) {
433 		gfs2_revoke_clean(sdp);
434 		return;
435 	}
436 	if (pass != 1)
437 		return;
438 
439 	fs_info(sdp, "jid=%u: Found %u revoke tags\n",
440 	        jd->jd_jid, sdp->sd_found_revokes);
441 
442 	gfs2_revoke_clean(sdp);
443 }
444 
445 static void rg_lo_add(struct gfs2_sbd *sdp, struct gfs2_log_element *le)
446 {
447 	struct gfs2_rgrpd *rgd;
448 	struct gfs2_trans *tr = current->journal_info;
449 
450 	tr->tr_touched = 1;
451 
452 	rgd = container_of(le, struct gfs2_rgrpd, rd_le);
453 
454 	gfs2_log_lock(sdp);
455 	if (!list_empty(&le->le_list)){
456 		gfs2_log_unlock(sdp);
457 		return;
458 	}
459 	gfs2_rgrp_bh_hold(rgd);
460 	sdp->sd_log_num_rg++;
461 	list_add(&le->le_list, &sdp->sd_log_le_rg);
462 	gfs2_log_unlock(sdp);
463 }
464 
465 static void rg_lo_after_commit(struct gfs2_sbd *sdp, struct gfs2_ail *ai)
466 {
467 	struct list_head *head = &sdp->sd_log_le_rg;
468 	struct gfs2_rgrpd *rgd;
469 
470 	while (!list_empty(head)) {
471 		rgd = list_entry(head->next, struct gfs2_rgrpd, rd_le.le_list);
472 		list_del_init(&rgd->rd_le.le_list);
473 		sdp->sd_log_num_rg--;
474 
475 		gfs2_rgrp_repolish_clones(rgd);
476 		gfs2_rgrp_bh_put(rgd);
477 	}
478 	gfs2_assert_warn(sdp, !sdp->sd_log_num_rg);
479 }
480 
481 /**
482  * databuf_lo_add - Add a databuf to the transaction.
483  *
484  * This is used in two distinct cases:
485  * i) In ordered write mode
486  *    We put the data buffer on a list so that we can ensure that its
487  *    synced to disk at the right time
488  * ii) In journaled data mode
489  *    We need to journal the data block in the same way as metadata in
490  *    the functions above. The difference is that here we have a tag
491  *    which is two __be64's being the block number (as per meta data)
492  *    and a flag which says whether the data block needs escaping or
493  *    not. This means we need a new log entry for each 251 or so data
494  *    blocks, which isn't an enormous overhead but twice as much as
495  *    for normal metadata blocks.
496  */
497 static void databuf_lo_add(struct gfs2_sbd *sdp, struct gfs2_log_element *le)
498 {
499 	struct gfs2_bufdata *bd = container_of(le, struct gfs2_bufdata, bd_le);
500 	struct gfs2_trans *tr = current->journal_info;
501 	struct address_space *mapping = bd->bd_bh->b_page->mapping;
502 	struct gfs2_inode *ip = GFS2_I(mapping->host);
503 
504 	lock_buffer(bd->bd_bh);
505 	gfs2_log_lock(sdp);
506 	if (tr) {
507 		if (!list_empty(&bd->bd_list_tr))
508 			goto out;
509 		tr->tr_touched = 1;
510 		if (gfs2_is_jdata(ip)) {
511 			tr->tr_num_buf++;
512 			list_add(&bd->bd_list_tr, &tr->tr_list_buf);
513 		}
514 	}
515 	if (!list_empty(&le->le_list))
516 		goto out;
517 
518 	set_bit(GLF_LFLUSH, &bd->bd_gl->gl_flags);
519 	set_bit(GLF_DIRTY, &bd->bd_gl->gl_flags);
520 	if (gfs2_is_jdata(ip)) {
521 		gfs2_pin(sdp, bd->bd_bh);
522 		tr->tr_num_databuf_new++;
523 		sdp->sd_log_num_databuf++;
524 		list_add(&le->le_list, &sdp->sd_log_le_databuf);
525 	} else {
526 		list_add(&le->le_list, &sdp->sd_log_le_ordered);
527 	}
528 out:
529 	gfs2_log_unlock(sdp);
530 	unlock_buffer(bd->bd_bh);
531 }
532 
533 static void gfs2_check_magic(struct buffer_head *bh)
534 {
535 	void *kaddr;
536 	__be32 *ptr;
537 
538 	clear_buffer_escaped(bh);
539 	kaddr = kmap_atomic(bh->b_page, KM_USER0);
540 	ptr = kaddr + bh_offset(bh);
541 	if (*ptr == cpu_to_be32(GFS2_MAGIC))
542 		set_buffer_escaped(bh);
543 	kunmap_atomic(kaddr, KM_USER0);
544 }
545 
546 static void gfs2_write_blocks(struct gfs2_sbd *sdp, struct buffer_head *bh,
547 			      struct list_head *list, struct list_head *done,
548 			      unsigned int n)
549 {
550 	struct buffer_head *bh1;
551 	struct gfs2_log_descriptor *ld;
552 	struct gfs2_bufdata *bd;
553 	__be64 *ptr;
554 
555 	if (!bh)
556 		return;
557 
558 	ld = bh_log_desc(bh);
559 	ld->ld_length = cpu_to_be32(n + 1);
560 	ld->ld_data1 = cpu_to_be32(n);
561 
562 	ptr = bh_log_ptr(bh);
563 
564 	get_bh(bh);
565 	submit_bh(WRITE_SYNC_PLUG, bh);
566 	gfs2_log_lock(sdp);
567 	while(!list_empty(list)) {
568 		bd = list_entry(list->next, struct gfs2_bufdata, bd_le.le_list);
569 		list_move_tail(&bd->bd_le.le_list, done);
570 		get_bh(bd->bd_bh);
571 		while (be64_to_cpu(*ptr) != bd->bd_bh->b_blocknr) {
572 			gfs2_log_incr_head(sdp);
573 			ptr += 2;
574 		}
575 		gfs2_log_unlock(sdp);
576 		lock_buffer(bd->bd_bh);
577 		if (buffer_escaped(bd->bd_bh)) {
578 			void *kaddr;
579 			bh1 = gfs2_log_get_buf(sdp);
580 			kaddr = kmap_atomic(bd->bd_bh->b_page, KM_USER0);
581 			memcpy(bh1->b_data, kaddr + bh_offset(bd->bd_bh),
582 			       bh1->b_size);
583 			kunmap_atomic(kaddr, KM_USER0);
584 			*(__be32 *)bh1->b_data = 0;
585 			clear_buffer_escaped(bd->bd_bh);
586 			unlock_buffer(bd->bd_bh);
587 			brelse(bd->bd_bh);
588 		} else {
589 			bh1 = gfs2_log_fake_buf(sdp, bd->bd_bh);
590 		}
591 		submit_bh(WRITE_SYNC_PLUG, bh1);
592 		gfs2_log_lock(sdp);
593 		ptr += 2;
594 	}
595 	gfs2_log_unlock(sdp);
596 	brelse(bh);
597 }
598 
599 /**
600  * databuf_lo_before_commit - Scan the data buffers, writing as we go
601  *
602  */
603 
604 static void databuf_lo_before_commit(struct gfs2_sbd *sdp)
605 {
606 	struct gfs2_bufdata *bd = NULL;
607 	struct buffer_head *bh = NULL;
608 	unsigned int n = 0;
609 	__be64 *ptr = NULL, *end = NULL;
610 	LIST_HEAD(processed);
611 	LIST_HEAD(in_progress);
612 
613 	gfs2_log_lock(sdp);
614 	while (!list_empty(&sdp->sd_log_le_databuf)) {
615 		if (ptr == end) {
616 			gfs2_log_unlock(sdp);
617 			gfs2_write_blocks(sdp, bh, &in_progress, &processed, n);
618 			n = 0;
619 			bh = gfs2_get_log_desc(sdp, GFS2_LOG_DESC_JDATA);
620 			ptr = bh_log_ptr(bh);
621 			end = bh_ptr_end(bh) - 1;
622 			gfs2_log_lock(sdp);
623 			continue;
624 		}
625 		bd = list_entry(sdp->sd_log_le_databuf.next, struct gfs2_bufdata, bd_le.le_list);
626 		list_move_tail(&bd->bd_le.le_list, &in_progress);
627 		gfs2_check_magic(bd->bd_bh);
628 		*ptr++ = cpu_to_be64(bd->bd_bh->b_blocknr);
629 		*ptr++ = cpu_to_be64(buffer_escaped(bh) ? 1 : 0);
630 		n++;
631 	}
632 	gfs2_log_unlock(sdp);
633 	gfs2_write_blocks(sdp, bh, &in_progress, &processed, n);
634 	gfs2_log_lock(sdp);
635 	list_splice(&processed, &sdp->sd_log_le_databuf);
636 	gfs2_log_unlock(sdp);
637 }
638 
639 static int databuf_lo_scan_elements(struct gfs2_jdesc *jd, unsigned int start,
640 				    struct gfs2_log_descriptor *ld,
641 				    __be64 *ptr, int pass)
642 {
643 	struct gfs2_inode *ip = GFS2_I(jd->jd_inode);
644 	struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
645 	struct gfs2_glock *gl = ip->i_gl;
646 	unsigned int blks = be32_to_cpu(ld->ld_data1);
647 	struct buffer_head *bh_log, *bh_ip;
648 	u64 blkno;
649 	u64 esc;
650 	int error = 0;
651 
652 	if (pass != 1 || be32_to_cpu(ld->ld_type) != GFS2_LOG_DESC_JDATA)
653 		return 0;
654 
655 	gfs2_replay_incr_blk(sdp, &start);
656 	for (; blks; gfs2_replay_incr_blk(sdp, &start), blks--) {
657 		blkno = be64_to_cpu(*ptr++);
658 		esc = be64_to_cpu(*ptr++);
659 
660 		sdp->sd_found_blocks++;
661 
662 		if (gfs2_revoke_check(sdp, blkno, start))
663 			continue;
664 
665 		error = gfs2_replay_read_block(jd, start, &bh_log);
666 		if (error)
667 			return error;
668 
669 		bh_ip = gfs2_meta_new(gl, blkno);
670 		memcpy(bh_ip->b_data, bh_log->b_data, bh_log->b_size);
671 
672 		/* Unescape */
673 		if (esc) {
674 			__be32 *eptr = (__be32 *)bh_ip->b_data;
675 			*eptr = cpu_to_be32(GFS2_MAGIC);
676 		}
677 		mark_buffer_dirty(bh_ip);
678 
679 		brelse(bh_log);
680 		brelse(bh_ip);
681 		if (error)
682 			break;
683 
684 		sdp->sd_replayed_blocks++;
685 	}
686 
687 	return error;
688 }
689 
690 /* FIXME: sort out accounting for log blocks etc. */
691 
692 static void databuf_lo_after_scan(struct gfs2_jdesc *jd, int error, int pass)
693 {
694 	struct gfs2_inode *ip = GFS2_I(jd->jd_inode);
695 	struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
696 
697 	if (error) {
698 		gfs2_meta_sync(ip->i_gl);
699 		return;
700 	}
701 	if (pass != 1)
702 		return;
703 
704 	/* data sync? */
705 	gfs2_meta_sync(ip->i_gl);
706 
707 	fs_info(sdp, "jid=%u: Replayed %u of %u data blocks\n",
708 		jd->jd_jid, sdp->sd_replayed_blocks, sdp->sd_found_blocks);
709 }
710 
711 static void databuf_lo_after_commit(struct gfs2_sbd *sdp, struct gfs2_ail *ai)
712 {
713 	struct list_head *head = &sdp->sd_log_le_databuf;
714 	struct gfs2_bufdata *bd;
715 
716 	while (!list_empty(head)) {
717 		bd = list_entry(head->next, struct gfs2_bufdata, bd_le.le_list);
718 		list_del_init(&bd->bd_le.le_list);
719 		sdp->sd_log_num_databuf--;
720 		gfs2_unpin(sdp, bd->bd_bh, ai);
721 	}
722 	gfs2_assert_warn(sdp, !sdp->sd_log_num_databuf);
723 }
724 
725 
726 const struct gfs2_log_operations gfs2_buf_lops = {
727 	.lo_add = buf_lo_add,
728 	.lo_before_commit = buf_lo_before_commit,
729 	.lo_after_commit = buf_lo_after_commit,
730 	.lo_before_scan = buf_lo_before_scan,
731 	.lo_scan_elements = buf_lo_scan_elements,
732 	.lo_after_scan = buf_lo_after_scan,
733 	.lo_name = "buf",
734 };
735 
736 const struct gfs2_log_operations gfs2_revoke_lops = {
737 	.lo_add = revoke_lo_add,
738 	.lo_before_commit = revoke_lo_before_commit,
739 	.lo_before_scan = revoke_lo_before_scan,
740 	.lo_scan_elements = revoke_lo_scan_elements,
741 	.lo_after_scan = revoke_lo_after_scan,
742 	.lo_name = "revoke",
743 };
744 
745 const struct gfs2_log_operations gfs2_rg_lops = {
746 	.lo_add = rg_lo_add,
747 	.lo_after_commit = rg_lo_after_commit,
748 	.lo_name = "rg",
749 };
750 
751 const struct gfs2_log_operations gfs2_databuf_lops = {
752 	.lo_add = databuf_lo_add,
753 	.lo_before_commit = databuf_lo_before_commit,
754 	.lo_after_commit = databuf_lo_after_commit,
755 	.lo_scan_elements = databuf_lo_scan_elements,
756 	.lo_after_scan = databuf_lo_after_scan,
757 	.lo_name = "databuf",
758 };
759 
760 const struct gfs2_log_operations *gfs2_log_ops[] = {
761 	&gfs2_databuf_lops,
762 	&gfs2_buf_lops,
763 	&gfs2_rg_lops,
764 	&gfs2_revoke_lops,
765 	NULL,
766 };
767 
768