xref: /linux/fs/nilfs2/bmap.c (revision 5bdef865eb358b6f3760e25e591ae115e9eeddef)
1 /*
2  * bmap.c - NILFS block mapping.
3  *
4  * Copyright (C) 2006-2008 Nippon Telegraph and Telephone Corporation.
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation; either version 2 of the License, or
9  * (at your option) any later version.
10  *
11  * This program is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  * GNU General Public License for more details.
15  *
16  * You should have received a copy of the GNU General Public License
17  * along with this program; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
19  *
20  * Written by Koji Sato <koji@osrg.net>.
21  */
22 
23 #include <linux/fs.h>
24 #include <linux/string.h>
25 #include <linux/errno.h>
26 #include "nilfs.h"
27 #include "bmap.h"
28 #include "sb.h"
29 #include "btnode.h"
30 #include "mdt.h"
31 #include "dat.h"
32 #include "alloc.h"
33 
34 struct inode *nilfs_bmap_get_dat(const struct nilfs_bmap *bmap)
35 {
36 	return nilfs_dat_inode(NILFS_I_NILFS(bmap->b_inode));
37 }
38 
39 int nilfs_bmap_lookup_at_level(struct nilfs_bmap *bmap, __u64 key, int level,
40 			       __u64 *ptrp)
41 {
42 	sector_t blocknr;
43 	int ret;
44 
45 	down_read(&bmap->b_sem);
46 	ret = bmap->b_ops->bop_lookup(bmap, key, level, ptrp);
47 	if (ret < 0)
48 		goto out;
49 	if (NILFS_BMAP_USE_VBN(bmap)) {
50 		ret = nilfs_dat_translate(nilfs_bmap_get_dat(bmap), *ptrp,
51 					  &blocknr);
52 		if (!ret)
53 			*ptrp = blocknr;
54 	}
55 
56  out:
57 	up_read(&bmap->b_sem);
58 	return ret;
59 }
60 
61 int nilfs_bmap_lookup_contig(struct nilfs_bmap *bmap, __u64 key, __u64 *ptrp,
62 			     unsigned maxblocks)
63 {
64 	int ret;
65 
66 	down_read(&bmap->b_sem);
67 	ret = bmap->b_ops->bop_lookup_contig(bmap, key, ptrp, maxblocks);
68 	up_read(&bmap->b_sem);
69 	return ret;
70 }
71 
72 /**
73  * nilfs_bmap_lookup - find a record
74  * @bmap: bmap
75  * @key: key
76  * @recp: pointer to record
77  *
78  * Description: nilfs_bmap_lookup() finds a record whose key matches @key in
79  * @bmap.
80  *
81  * Return Value: On success, 0 is returned and the record associated with @key
82  * is stored in the place pointed by @recp. On error, one of the following
83  * negative error codes is returned.
84  *
85  * %-EIO - I/O error.
86  *
87  * %-ENOMEM - Insufficient amount of memory available.
88  *
89  * %-ENOENT - A record associated with @key does not exist.
90  */
91 int nilfs_bmap_lookup(struct nilfs_bmap *bmap,
92 		      unsigned long key,
93 		      unsigned long *recp)
94 {
95 	__u64 ptr;
96 	int ret;
97 
98 	/* XXX: use macro for level 1 */
99 	ret = nilfs_bmap_lookup_at_level(bmap, key, 1, &ptr);
100 	if (recp != NULL)
101 		*recp = ptr;
102 	return ret;
103 }
104 
105 static int nilfs_bmap_do_insert(struct nilfs_bmap *bmap, __u64 key, __u64 ptr)
106 {
107 	__u64 keys[NILFS_BMAP_SMALL_HIGH + 1];
108 	__u64 ptrs[NILFS_BMAP_SMALL_HIGH + 1];
109 	int ret, n;
110 
111 	if (bmap->b_ops->bop_check_insert != NULL) {
112 		ret = bmap->b_ops->bop_check_insert(bmap, key);
113 		if (ret > 0) {
114 			n = bmap->b_ops->bop_gather_data(
115 				bmap, keys, ptrs, NILFS_BMAP_SMALL_HIGH + 1);
116 			if (n < 0)
117 				return n;
118 			ret = nilfs_btree_convert_and_insert(
119 				bmap, key, ptr, keys, ptrs, n);
120 			if (ret == 0)
121 				bmap->b_u.u_flags |= NILFS_BMAP_LARGE;
122 
123 			return ret;
124 		} else if (ret < 0)
125 			return ret;
126 	}
127 
128 	return bmap->b_ops->bop_insert(bmap, key, ptr);
129 }
130 
131 /**
132  * nilfs_bmap_insert - insert a new key-record pair into a bmap
133  * @bmap: bmap
134  * @key: key
135  * @rec: record
136  *
137  * Description: nilfs_bmap_insert() inserts the new key-record pair specified
138  * by @key and @rec into @bmap.
139  *
140  * Return Value: On success, 0 is returned. On error, one of the following
141  * negative error codes is returned.
142  *
143  * %-EIO - I/O error.
144  *
145  * %-ENOMEM - Insufficient amount of memory available.
146  *
147  * %-EEXIST - A record associated with @key already exist.
148  */
149 int nilfs_bmap_insert(struct nilfs_bmap *bmap,
150 		      unsigned long key,
151 		      unsigned long rec)
152 {
153 	int ret;
154 
155 	down_write(&bmap->b_sem);
156 	ret = nilfs_bmap_do_insert(bmap, key, rec);
157 	up_write(&bmap->b_sem);
158 	return ret;
159 }
160 
161 static int nilfs_bmap_do_delete(struct nilfs_bmap *bmap, __u64 key)
162 {
163 	__u64 keys[NILFS_BMAP_LARGE_LOW + 1];
164 	__u64 ptrs[NILFS_BMAP_LARGE_LOW + 1];
165 	int ret, n;
166 
167 	if (bmap->b_ops->bop_check_delete != NULL) {
168 		ret = bmap->b_ops->bop_check_delete(bmap, key);
169 		if (ret > 0) {
170 			n = bmap->b_ops->bop_gather_data(
171 				bmap, keys, ptrs, NILFS_BMAP_LARGE_LOW + 1);
172 			if (n < 0)
173 				return n;
174 			ret = nilfs_direct_delete_and_convert(
175 				bmap, key, keys, ptrs, n);
176 			if (ret == 0)
177 				bmap->b_u.u_flags &= ~NILFS_BMAP_LARGE;
178 
179 			return ret;
180 		} else if (ret < 0)
181 			return ret;
182 	}
183 
184 	return bmap->b_ops->bop_delete(bmap, key);
185 }
186 
187 int nilfs_bmap_last_key(struct nilfs_bmap *bmap, unsigned long *key)
188 {
189 	__u64 lastkey;
190 	int ret;
191 
192 	down_read(&bmap->b_sem);
193 	ret = bmap->b_ops->bop_last_key(bmap, &lastkey);
194 	if (!ret)
195 		*key = lastkey;
196 	up_read(&bmap->b_sem);
197 	return ret;
198 }
199 
200 /**
201  * nilfs_bmap_delete - delete a key-record pair from a bmap
202  * @bmap: bmap
203  * @key: key
204  *
205  * Description: nilfs_bmap_delete() deletes the key-record pair specified by
206  * @key from @bmap.
207  *
208  * Return Value: On success, 0 is returned. On error, one of the following
209  * negative error codes is returned.
210  *
211  * %-EIO - I/O error.
212  *
213  * %-ENOMEM - Insufficient amount of memory available.
214  *
215  * %-ENOENT - A record associated with @key does not exist.
216  */
217 int nilfs_bmap_delete(struct nilfs_bmap *bmap, unsigned long key)
218 {
219 	int ret;
220 
221 	down_write(&bmap->b_sem);
222 	ret = nilfs_bmap_do_delete(bmap, key);
223 	up_write(&bmap->b_sem);
224 	return ret;
225 }
226 
227 static int nilfs_bmap_do_truncate(struct nilfs_bmap *bmap, unsigned long key)
228 {
229 	__u64 lastkey;
230 	int ret;
231 
232 	ret = bmap->b_ops->bop_last_key(bmap, &lastkey);
233 	if (ret < 0) {
234 		if (ret == -ENOENT)
235 			ret = 0;
236 		return ret;
237 	}
238 
239 	while (key <= lastkey) {
240 		ret = nilfs_bmap_do_delete(bmap, lastkey);
241 		if (ret < 0)
242 			return ret;
243 		ret = bmap->b_ops->bop_last_key(bmap, &lastkey);
244 		if (ret < 0) {
245 			if (ret == -ENOENT)
246 				ret = 0;
247 			return ret;
248 		}
249 	}
250 	return 0;
251 }
252 
253 /**
254  * nilfs_bmap_truncate - truncate a bmap to a specified key
255  * @bmap: bmap
256  * @key: key
257  *
258  * Description: nilfs_bmap_truncate() removes key-record pairs whose keys are
259  * greater than or equal to @key from @bmap.
260  *
261  * Return Value: On success, 0 is returned. On error, one of the following
262  * negative error codes is returned.
263  *
264  * %-EIO - I/O error.
265  *
266  * %-ENOMEM - Insufficient amount of memory available.
267  */
268 int nilfs_bmap_truncate(struct nilfs_bmap *bmap, unsigned long key)
269 {
270 	int ret;
271 
272 	down_write(&bmap->b_sem);
273 	ret = nilfs_bmap_do_truncate(bmap, key);
274 	up_write(&bmap->b_sem);
275 	return ret;
276 }
277 
278 /**
279  * nilfs_bmap_clear - free resources a bmap holds
280  * @bmap: bmap
281  *
282  * Description: nilfs_bmap_clear() frees resources associated with @bmap.
283  */
284 void nilfs_bmap_clear(struct nilfs_bmap *bmap)
285 {
286 	down_write(&bmap->b_sem);
287 	if (bmap->b_ops->bop_clear != NULL)
288 		bmap->b_ops->bop_clear(bmap);
289 	up_write(&bmap->b_sem);
290 }
291 
292 /**
293  * nilfs_bmap_propagate - propagate dirty state
294  * @bmap: bmap
295  * @bh: buffer head
296  *
297  * Description: nilfs_bmap_propagate() marks the buffers that directly or
298  * indirectly refer to the block specified by @bh dirty.
299  *
300  * Return Value: On success, 0 is returned. On error, one of the following
301  * negative error codes is returned.
302  *
303  * %-EIO - I/O error.
304  *
305  * %-ENOMEM - Insufficient amount of memory available.
306  */
307 int nilfs_bmap_propagate(struct nilfs_bmap *bmap, struct buffer_head *bh)
308 {
309 	int ret;
310 
311 	down_write(&bmap->b_sem);
312 	ret = bmap->b_ops->bop_propagate(bmap, bh);
313 	up_write(&bmap->b_sem);
314 	return ret;
315 }
316 
317 /**
318  * nilfs_bmap_lookup_dirty_buffers -
319  * @bmap: bmap
320  * @listp: pointer to buffer head list
321  */
322 void nilfs_bmap_lookup_dirty_buffers(struct nilfs_bmap *bmap,
323 				     struct list_head *listp)
324 {
325 	if (bmap->b_ops->bop_lookup_dirty_buffers != NULL)
326 		bmap->b_ops->bop_lookup_dirty_buffers(bmap, listp);
327 }
328 
329 /**
330  * nilfs_bmap_assign - assign a new block number to a block
331  * @bmap: bmap
332  * @bhp: pointer to buffer head
333  * @blocknr: block number
334  * @binfo: block information
335  *
336  * Description: nilfs_bmap_assign() assigns the block number @blocknr to the
337  * buffer specified by @bh.
338  *
339  * Return Value: On success, 0 is returned and the buffer head of a newly
340  * create buffer and the block information associated with the buffer are
341  * stored in the place pointed by @bh and @binfo, respectively. On error, one
342  * of the following negative error codes is returned.
343  *
344  * %-EIO - I/O error.
345  *
346  * %-ENOMEM - Insufficient amount of memory available.
347  */
348 int nilfs_bmap_assign(struct nilfs_bmap *bmap,
349 		      struct buffer_head **bh,
350 		      unsigned long blocknr,
351 		      union nilfs_binfo *binfo)
352 {
353 	int ret;
354 
355 	down_write(&bmap->b_sem);
356 	ret = bmap->b_ops->bop_assign(bmap, bh, blocknr, binfo);
357 	up_write(&bmap->b_sem);
358 	return ret;
359 }
360 
361 /**
362  * nilfs_bmap_mark - mark block dirty
363  * @bmap: bmap
364  * @key: key
365  * @level: level
366  *
367  * Description: nilfs_bmap_mark() marks the block specified by @key and @level
368  * as dirty.
369  *
370  * Return Value: On success, 0 is returned. On error, one of the following
371  * negative error codes is returned.
372  *
373  * %-EIO - I/O error.
374  *
375  * %-ENOMEM - Insufficient amount of memory available.
376  */
377 int nilfs_bmap_mark(struct nilfs_bmap *bmap, __u64 key, int level)
378 {
379 	int ret;
380 
381 	if (bmap->b_ops->bop_mark == NULL)
382 		return 0;
383 
384 	down_write(&bmap->b_sem);
385 	ret = bmap->b_ops->bop_mark(bmap, key, level);
386 	up_write(&bmap->b_sem);
387 	return ret;
388 }
389 
390 /**
391  * nilfs_bmap_test_and_clear_dirty - test and clear a bmap dirty state
392  * @bmap: bmap
393  *
394  * Description: nilfs_test_and_clear() is the atomic operation to test and
395  * clear the dirty state of @bmap.
396  *
397  * Return Value: 1 is returned if @bmap is dirty, or 0 if clear.
398  */
399 int nilfs_bmap_test_and_clear_dirty(struct nilfs_bmap *bmap)
400 {
401 	int ret;
402 
403 	down_write(&bmap->b_sem);
404 	ret = nilfs_bmap_dirty(bmap);
405 	nilfs_bmap_clear_dirty(bmap);
406 	up_write(&bmap->b_sem);
407 	return ret;
408 }
409 
410 
411 /*
412  * Internal use only
413  */
414 
415 void nilfs_bmap_add_blocks(const struct nilfs_bmap *bmap, int n)
416 {
417 	inode_add_bytes(bmap->b_inode, (1 << bmap->b_inode->i_blkbits) * n);
418 	if (NILFS_MDT(bmap->b_inode))
419 		nilfs_mdt_mark_dirty(bmap->b_inode);
420 	else
421 		mark_inode_dirty(bmap->b_inode);
422 }
423 
424 void nilfs_bmap_sub_blocks(const struct nilfs_bmap *bmap, int n)
425 {
426 	inode_sub_bytes(bmap->b_inode, (1 << bmap->b_inode->i_blkbits) * n);
427 	if (NILFS_MDT(bmap->b_inode))
428 		nilfs_mdt_mark_dirty(bmap->b_inode);
429 	else
430 		mark_inode_dirty(bmap->b_inode);
431 }
432 
433 __u64 nilfs_bmap_data_get_key(const struct nilfs_bmap *bmap,
434 			      const struct buffer_head *bh)
435 {
436 	struct buffer_head *pbh;
437 	__u64 key;
438 
439 	key = page_index(bh->b_page) << (PAGE_CACHE_SHIFT -
440 					 bmap->b_inode->i_blkbits);
441 	for (pbh = page_buffers(bh->b_page); pbh != bh;
442 	     pbh = pbh->b_this_page, key++);
443 
444 	return key;
445 }
446 
447 __u64 nilfs_bmap_find_target_seq(const struct nilfs_bmap *bmap, __u64 key)
448 {
449 	__s64 diff;
450 
451 	diff = key - bmap->b_last_allocated_key;
452 	if ((nilfs_bmap_keydiff_abs(diff) < NILFS_INODE_BMAP_SIZE) &&
453 	    (bmap->b_last_allocated_ptr != NILFS_BMAP_INVALID_PTR) &&
454 	    (bmap->b_last_allocated_ptr + diff > 0))
455 		return bmap->b_last_allocated_ptr + diff;
456 	else
457 		return NILFS_BMAP_INVALID_PTR;
458 }
459 
460 #define NILFS_BMAP_GROUP_DIV	8
461 __u64 nilfs_bmap_find_target_in_group(const struct nilfs_bmap *bmap)
462 {
463 	struct inode *dat = nilfs_bmap_get_dat(bmap);
464 	unsigned long entries_per_group = nilfs_palloc_entries_per_group(dat);
465 	unsigned long group = bmap->b_inode->i_ino / entries_per_group;
466 
467 	return group * entries_per_group +
468 		(bmap->b_inode->i_ino % NILFS_BMAP_GROUP_DIV) *
469 		(entries_per_group / NILFS_BMAP_GROUP_DIV);
470 }
471 
472 int nilfs_bmap_prepare_alloc_v(struct nilfs_bmap *bmap,
473 				 union nilfs_bmap_ptr_req *req)
474 {
475 	return nilfs_dat_prepare_alloc(nilfs_bmap_get_dat(bmap), &req->bpr_req);
476 }
477 
478 void nilfs_bmap_commit_alloc_v(struct nilfs_bmap *bmap,
479 				 union nilfs_bmap_ptr_req *req)
480 {
481 	nilfs_dat_commit_alloc(nilfs_bmap_get_dat(bmap), &req->bpr_req);
482 }
483 
484 void nilfs_bmap_abort_alloc_v(struct nilfs_bmap *bmap,
485 			      union nilfs_bmap_ptr_req *req)
486 {
487 	nilfs_dat_abort_alloc(nilfs_bmap_get_dat(bmap), &req->bpr_req);
488 }
489 
490 int nilfs_bmap_start_v(struct nilfs_bmap *bmap, union nilfs_bmap_ptr_req *req,
491 		       sector_t blocknr)
492 {
493 	struct inode *dat = nilfs_bmap_get_dat(bmap);
494 	int ret;
495 
496 	ret = nilfs_dat_prepare_start(dat, &req->bpr_req);
497 	if (likely(!ret))
498 		nilfs_dat_commit_start(dat, &req->bpr_req, blocknr);
499 	return ret;
500 }
501 
502 int nilfs_bmap_prepare_end_v(struct nilfs_bmap *bmap,
503 			     union nilfs_bmap_ptr_req *req)
504 {
505 	return nilfs_dat_prepare_end(nilfs_bmap_get_dat(bmap), &req->bpr_req);
506 }
507 
508 void nilfs_bmap_commit_end_v(struct nilfs_bmap *bmap,
509 			     union nilfs_bmap_ptr_req *req)
510 {
511 	nilfs_dat_commit_end(nilfs_bmap_get_dat(bmap), &req->bpr_req,
512 			     bmap->b_ptr_type == NILFS_BMAP_PTR_VS);
513 }
514 
515 void nilfs_bmap_abort_end_v(struct nilfs_bmap *bmap,
516 			    union nilfs_bmap_ptr_req *req)
517 {
518 	nilfs_dat_abort_end(nilfs_bmap_get_dat(bmap), &req->bpr_req);
519 }
520 
521 int nilfs_bmap_move_v(const struct nilfs_bmap *bmap, __u64 vblocknr,
522 		      sector_t blocknr)
523 {
524 	return nilfs_dat_move(nilfs_bmap_get_dat(bmap), vblocknr, blocknr);
525 }
526 
527 int nilfs_bmap_mark_dirty(const struct nilfs_bmap *bmap, __u64 vblocknr)
528 {
529 	return nilfs_dat_mark_dirty(nilfs_bmap_get_dat(bmap), vblocknr);
530 }
531 
532 int nilfs_bmap_prepare_update_v(struct nilfs_bmap *bmap,
533 				union nilfs_bmap_ptr_req *oldreq,
534 				union nilfs_bmap_ptr_req *newreq)
535 {
536 	struct inode *dat = nilfs_bmap_get_dat(bmap);
537 	int ret;
538 
539 	ret = nilfs_dat_prepare_end(dat, &oldreq->bpr_req);
540 	if (ret < 0)
541 		return ret;
542 	ret = nilfs_dat_prepare_alloc(dat, &newreq->bpr_req);
543 	if (ret < 0)
544 		nilfs_dat_abort_end(dat, &oldreq->bpr_req);
545 
546 	return ret;
547 }
548 
549 void nilfs_bmap_commit_update_v(struct nilfs_bmap *bmap,
550 				union nilfs_bmap_ptr_req *oldreq,
551 				union nilfs_bmap_ptr_req *newreq)
552 {
553 	struct inode *dat = nilfs_bmap_get_dat(bmap);
554 
555 	nilfs_dat_commit_end(dat, &oldreq->bpr_req,
556 			     bmap->b_ptr_type == NILFS_BMAP_PTR_VS);
557 	nilfs_dat_commit_alloc(dat, &newreq->bpr_req);
558 }
559 
560 void nilfs_bmap_abort_update_v(struct nilfs_bmap *bmap,
561 			       union nilfs_bmap_ptr_req *oldreq,
562 			       union nilfs_bmap_ptr_req *newreq)
563 {
564 	struct inode *dat = nilfs_bmap_get_dat(bmap);
565 
566 	nilfs_dat_abort_end(dat, &oldreq->bpr_req);
567 	nilfs_dat_abort_alloc(dat, &newreq->bpr_req);
568 }
569 
570 static struct lock_class_key nilfs_bmap_dat_lock_key;
571 static struct lock_class_key nilfs_bmap_mdt_lock_key;
572 
573 /**
574  * nilfs_bmap_read - read a bmap from an inode
575  * @bmap: bmap
576  * @raw_inode: on-disk inode
577  *
578  * Description: nilfs_bmap_read() initializes the bmap @bmap.
579  *
580  * Return Value: On success, 0 is returned. On error, the following negative
581  * error code is returned.
582  *
583  * %-ENOMEM - Insufficient amount of memory available.
584  */
585 int nilfs_bmap_read(struct nilfs_bmap *bmap, struct nilfs_inode *raw_inode)
586 {
587 	if (raw_inode == NULL)
588 		memset(bmap->b_u.u_data, 0, NILFS_BMAP_SIZE);
589 	else
590 		memcpy(bmap->b_u.u_data, raw_inode->i_bmap, NILFS_BMAP_SIZE);
591 
592 	init_rwsem(&bmap->b_sem);
593 	bmap->b_state = 0;
594 	bmap->b_inode = &NILFS_BMAP_I(bmap)->vfs_inode;
595 	switch (bmap->b_inode->i_ino) {
596 	case NILFS_DAT_INO:
597 		bmap->b_ptr_type = NILFS_BMAP_PTR_P;
598 		bmap->b_last_allocated_key = 0;
599 		bmap->b_last_allocated_ptr = NILFS_BMAP_NEW_PTR_INIT;
600 		lockdep_set_class(&bmap->b_sem, &nilfs_bmap_dat_lock_key);
601 		break;
602 	case NILFS_CPFILE_INO:
603 	case NILFS_SUFILE_INO:
604 		bmap->b_ptr_type = NILFS_BMAP_PTR_VS;
605 		bmap->b_last_allocated_key = 0;
606 		bmap->b_last_allocated_ptr = NILFS_BMAP_INVALID_PTR;
607 		lockdep_set_class(&bmap->b_sem, &nilfs_bmap_mdt_lock_key);
608 		break;
609 	case NILFS_IFILE_INO:
610 		lockdep_set_class(&bmap->b_sem, &nilfs_bmap_mdt_lock_key);
611 		/* Fall through */
612 	default:
613 		bmap->b_ptr_type = NILFS_BMAP_PTR_VM;
614 		bmap->b_last_allocated_key = 0;
615 		bmap->b_last_allocated_ptr = NILFS_BMAP_INVALID_PTR;
616 		break;
617 	}
618 
619 	return (bmap->b_u.u_flags & NILFS_BMAP_LARGE) ?
620 		nilfs_btree_init(bmap) : nilfs_direct_init(bmap);
621 }
622 
623 /**
624  * nilfs_bmap_write - write back a bmap to an inode
625  * @bmap: bmap
626  * @raw_inode: on-disk inode
627  *
628  * Description: nilfs_bmap_write() stores @bmap in @raw_inode.
629  */
630 void nilfs_bmap_write(struct nilfs_bmap *bmap, struct nilfs_inode *raw_inode)
631 {
632 	down_write(&bmap->b_sem);
633 	memcpy(raw_inode->i_bmap, bmap->b_u.u_data,
634 	       NILFS_INODE_BMAP_SIZE * sizeof(__le64));
635 	if (bmap->b_inode->i_ino == NILFS_DAT_INO)
636 		bmap->b_last_allocated_ptr = NILFS_BMAP_NEW_PTR_INIT;
637 
638 	up_write(&bmap->b_sem);
639 }
640 
641 void nilfs_bmap_init_gc(struct nilfs_bmap *bmap)
642 {
643 	memset(&bmap->b_u, 0, NILFS_BMAP_SIZE);
644 	init_rwsem(&bmap->b_sem);
645 	bmap->b_inode = &NILFS_BMAP_I(bmap)->vfs_inode;
646 	bmap->b_ptr_type = NILFS_BMAP_PTR_U;
647 	bmap->b_last_allocated_key = 0;
648 	bmap->b_last_allocated_ptr = NILFS_BMAP_INVALID_PTR;
649 	bmap->b_state = 0;
650 	nilfs_btree_init_gc(bmap);
651 }
652 
653 void nilfs_bmap_init_gcdat(struct nilfs_bmap *gcbmap, struct nilfs_bmap *bmap)
654 {
655 	memcpy(gcbmap, bmap, sizeof(union nilfs_bmap_union));
656 	init_rwsem(&gcbmap->b_sem);
657 	lockdep_set_class(&bmap->b_sem, &nilfs_bmap_dat_lock_key);
658 	gcbmap->b_inode = &NILFS_BMAP_I(gcbmap)->vfs_inode;
659 }
660 
661 void nilfs_bmap_commit_gcdat(struct nilfs_bmap *gcbmap, struct nilfs_bmap *bmap)
662 {
663 	memcpy(bmap, gcbmap, sizeof(union nilfs_bmap_union));
664 	init_rwsem(&bmap->b_sem);
665 	lockdep_set_class(&bmap->b_sem, &nilfs_bmap_dat_lock_key);
666 	bmap->b_inode = &NILFS_BMAP_I(bmap)->vfs_inode;
667 }
668