blob: 892cf5ffdb8e165a373ae6e44036ef58ee1f5df2 [file] [log] [blame]
Ryusuke Konishi5eb563f2009-04-06 19:01:28 -07001/*
2 * mdt.c - meta data file for NILFS
3 *
4 * Copyright (C) 2005-2008 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 Ryusuke Konishi <ryusuke@osrg.net>
21 */
22
23#include <linux/buffer_head.h>
24#include <linux/mpage.h>
25#include <linux/mm.h>
26#include <linux/writeback.h>
27#include <linux/backing-dev.h>
28#include <linux/swap.h>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090029#include <linux/slab.h>
Ryusuke Konishi5eb563f2009-04-06 19:01:28 -070030#include "nilfs.h"
Ryusuke Konishi05d0e942010-07-10 20:52:09 +090031#include "btnode.h"
Ryusuke Konishi5eb563f2009-04-06 19:01:28 -070032#include "segment.h"
33#include "page.h"
34#include "mdt.h"
35
36
37#define NILFS_MDT_MAX_RA_BLOCKS (16 - 1)
38
Ryusuke Konishi5eb563f2009-04-06 19:01:28 -070039
40static int
41nilfs_mdt_insert_new_block(struct inode *inode, unsigned long block,
42 struct buffer_head *bh,
43 void (*init_block)(struct inode *,
44 struct buffer_head *, void *))
45{
46 struct nilfs_inode_info *ii = NILFS_I(inode);
47 void *kaddr;
48 int ret;
49
50 /* Caller exclude read accesses using page lock */
51
52 /* set_buffer_new(bh); */
53 bh->b_blocknr = 0;
54
55 ret = nilfs_bmap_insert(ii->i_bmap, block, (unsigned long)bh);
56 if (unlikely(ret))
57 return ret;
58
59 set_buffer_mapped(bh);
60
Cong Wang7b9c0972011-11-25 23:14:33 +080061 kaddr = kmap_atomic(bh->b_page);
Ryusuke Konishi5eb563f2009-04-06 19:01:28 -070062 memset(kaddr + bh_offset(bh), 0, 1 << inode->i_blkbits);
63 if (init_block)
64 init_block(inode, bh, kaddr);
65 flush_dcache_page(bh->b_page);
Cong Wang7b9c0972011-11-25 23:14:33 +080066 kunmap_atomic(kaddr);
Ryusuke Konishi5eb563f2009-04-06 19:01:28 -070067
68 set_buffer_uptodate(bh);
Ryusuke Konishi5fc7b142011-05-05 12:56:51 +090069 mark_buffer_dirty(bh);
Ryusuke Konishi5eb563f2009-04-06 19:01:28 -070070 nilfs_mdt_mark_dirty(inode);
71 return 0;
72}
73
74static int nilfs_mdt_create_block(struct inode *inode, unsigned long block,
75 struct buffer_head **out_bh,
76 void (*init_block)(struct inode *,
77 struct buffer_head *,
78 void *))
79{
Ryusuke Konishi5eb563f2009-04-06 19:01:28 -070080 struct super_block *sb = inode->i_sb;
81 struct nilfs_transaction_info ti;
82 struct buffer_head *bh;
83 int err;
84
Ryusuke Konishi5eb563f2009-04-06 19:01:28 -070085 nilfs_transaction_begin(sb, &ti, 0);
86
87 err = -ENOMEM;
88 bh = nilfs_grab_buffer(inode, inode->i_mapping, block, 0);
89 if (unlikely(!bh))
90 goto failed_unlock;
91
92 err = -EEXIST;
Ryusuke Konishi14351102009-09-06 17:49:49 +090093 if (buffer_uptodate(bh))
Ryusuke Konishi5eb563f2009-04-06 19:01:28 -070094 goto failed_bh;
Ryusuke Konishi14351102009-09-06 17:49:49 +090095
Ryusuke Konishi5eb563f2009-04-06 19:01:28 -070096 wait_on_buffer(bh);
97 if (buffer_uptodate(bh))
98 goto failed_bh;
Ryusuke Konishi5eb563f2009-04-06 19:01:28 -070099
Ryusuke Konishi090fd5b2010-09-05 16:17:35 +0900100 bh->b_bdev = sb->s_bdev;
Ryusuke Konishi5eb563f2009-04-06 19:01:28 -0700101 err = nilfs_mdt_insert_new_block(inode, block, bh, init_block);
102 if (likely(!err)) {
103 get_bh(bh);
104 *out_bh = bh;
105 }
106
107 failed_bh:
108 unlock_page(bh->b_page);
109 page_cache_release(bh->b_page);
110 brelse(bh);
111
112 failed_unlock:
Ryusuke Konishi47420c72009-04-06 19:01:45 -0700113 if (likely(!err))
114 err = nilfs_transaction_commit(sb);
115 else
116 nilfs_transaction_abort(sb);
Ryusuke Konishi090fd5b2010-09-05 16:17:35 +0900117
Ryusuke Konishi5eb563f2009-04-06 19:01:28 -0700118 return err;
119}
120
121static int
122nilfs_mdt_submit_block(struct inode *inode, unsigned long blkoff,
123 int mode, struct buffer_head **out_bh)
124{
125 struct buffer_head *bh;
Ryusuke Konishi0f3fe332009-08-15 02:29:28 +0900126 __u64 blknum = 0;
Ryusuke Konishi5eb563f2009-04-06 19:01:28 -0700127 int ret = -ENOMEM;
128
129 bh = nilfs_grab_buffer(inode, inode->i_mapping, blkoff, 0);
130 if (unlikely(!bh))
131 goto failed;
132
133 ret = -EEXIST; /* internal code */
134 if (buffer_uptodate(bh))
135 goto out;
136
137 if (mode == READA) {
138 if (!trylock_buffer(bh)) {
139 ret = -EBUSY;
140 goto failed_bh;
141 }
Ryusuke Konishi1f5abe72009-04-06 19:01:55 -0700142 } else /* mode == READ */
Ryusuke Konishi5eb563f2009-04-06 19:01:28 -0700143 lock_buffer(bh);
Ryusuke Konishi5eb563f2009-04-06 19:01:28 -0700144
145 if (buffer_uptodate(bh)) {
146 unlock_buffer(bh);
147 goto out;
148 }
Ryusuke Konishi14351102009-09-06 17:49:49 +0900149
150 ret = nilfs_bmap_lookup(NILFS_I(inode)->i_bmap, blkoff, &blknum);
151 if (unlikely(ret)) {
152 unlock_buffer(bh);
153 goto failed_bh;
Ryusuke Konishi5eb563f2009-04-06 19:01:28 -0700154 }
Ryusuke Konishic6e07182010-09-05 00:23:50 +0900155 map_bh(bh, inode->i_sb, (sector_t)blknum);
Ryusuke Konishi5eb563f2009-04-06 19:01:28 -0700156
157 bh->b_end_io = end_buffer_read_sync;
158 get_bh(bh);
159 submit_bh(mode, bh);
160 ret = 0;
161 out:
162 get_bh(bh);
163 *out_bh = bh;
164
165 failed_bh:
166 unlock_page(bh->b_page);
167 page_cache_release(bh->b_page);
168 brelse(bh);
169 failed:
170 return ret;
171}
172
173static int nilfs_mdt_read_block(struct inode *inode, unsigned long block,
Ryusuke Konishib34a6502009-11-14 00:09:47 +0900174 int readahead, struct buffer_head **out_bh)
Ryusuke Konishi5eb563f2009-04-06 19:01:28 -0700175{
176 struct buffer_head *first_bh, *bh;
177 unsigned long blkoff;
178 int i, nr_ra_blocks = NILFS_MDT_MAX_RA_BLOCKS;
179 int err;
180
181 err = nilfs_mdt_submit_block(inode, block, READ, &first_bh);
182 if (err == -EEXIST) /* internal code */
183 goto out;
184
185 if (unlikely(err))
186 goto failed;
187
Ryusuke Konishib34a6502009-11-14 00:09:47 +0900188 if (readahead) {
189 blkoff = block + 1;
190 for (i = 0; i < nr_ra_blocks; i++, blkoff++) {
191 err = nilfs_mdt_submit_block(inode, blkoff, READA, &bh);
192 if (likely(!err || err == -EEXIST))
193 brelse(bh);
194 else if (err != -EBUSY)
195 break;
196 /* abort readahead if bmap lookup failed */
197 if (!buffer_locked(first_bh))
198 goto out_no_wait;
199 }
Ryusuke Konishi5eb563f2009-04-06 19:01:28 -0700200 }
201
202 wait_on_buffer(first_bh);
203
204 out_no_wait:
205 err = -EIO;
206 if (!buffer_uptodate(first_bh))
207 goto failed_bh;
208 out:
209 *out_bh = first_bh;
210 return 0;
211
212 failed_bh:
213 brelse(first_bh);
214 failed:
215 return err;
216}
217
218/**
219 * nilfs_mdt_get_block - read or create a buffer on meta data file.
220 * @inode: inode of the meta data file
221 * @blkoff: block offset
222 * @create: create flag
223 * @init_block: initializer used for newly allocated block
224 * @out_bh: output of a pointer to the buffer_head
225 *
226 * nilfs_mdt_get_block() looks up the specified buffer and tries to create
227 * a new buffer if @create is not zero. On success, the returned buffer is
228 * assured to be either existing or formatted using a buffer lock on success.
229 * @out_bh is substituted only when zero is returned.
230 *
231 * Return Value: On success, it returns 0. On error, the following negative
232 * error code is returned.
233 *
234 * %-ENOMEM - Insufficient memory available.
235 *
236 * %-EIO - I/O error
237 *
238 * %-ENOENT - the specified block does not exist (hole block)
239 *
Ryusuke Konishi5eb563f2009-04-06 19:01:28 -0700240 * %-EROFS - Read only filesystem (for create mode)
241 */
242int nilfs_mdt_get_block(struct inode *inode, unsigned long blkoff, int create,
243 void (*init_block)(struct inode *,
244 struct buffer_head *, void *),
245 struct buffer_head **out_bh)
246{
247 int ret;
248
249 /* Should be rewritten with merging nilfs_mdt_read_block() */
250 retry:
Ryusuke Konishib34a6502009-11-14 00:09:47 +0900251 ret = nilfs_mdt_read_block(inode, blkoff, !create, out_bh);
Ryusuke Konishi5eb563f2009-04-06 19:01:28 -0700252 if (!create || ret != -ENOENT)
253 return ret;
254
255 ret = nilfs_mdt_create_block(inode, blkoff, out_bh, init_block);
256 if (unlikely(ret == -EEXIST)) {
257 /* create = 0; */ /* limit read-create loop retries */
258 goto retry;
259 }
260 return ret;
261}
262
263/**
264 * nilfs_mdt_delete_block - make a hole on the meta data file.
265 * @inode: inode of the meta data file
266 * @block: block offset
267 *
268 * Return Value: On success, zero is returned.
269 * On error, one of the following negative error code is returned.
270 *
271 * %-ENOMEM - Insufficient memory available.
272 *
273 * %-EIO - I/O error
Ryusuke Konishi5eb563f2009-04-06 19:01:28 -0700274 */
275int nilfs_mdt_delete_block(struct inode *inode, unsigned long block)
276{
277 struct nilfs_inode_info *ii = NILFS_I(inode);
278 int err;
279
280 err = nilfs_bmap_delete(ii->i_bmap, block);
Ryusuke Konishi84338232009-05-05 21:52:06 +0900281 if (!err || err == -ENOENT) {
Ryusuke Konishi5eb563f2009-04-06 19:01:28 -0700282 nilfs_mdt_mark_dirty(inode);
283 nilfs_mdt_forget_block(inode, block);
284 }
285 return err;
286}
287
288/**
289 * nilfs_mdt_forget_block - discard dirty state and try to remove the page
290 * @inode: inode of the meta data file
291 * @block: block offset
292 *
293 * nilfs_mdt_forget_block() clears a dirty flag of the specified buffer, and
294 * tries to release the page including the buffer from a page cache.
295 *
296 * Return Value: On success, 0 is returned. On error, one of the following
297 * negative error code is returned.
298 *
299 * %-EBUSY - page has an active buffer.
300 *
301 * %-ENOENT - page cache has no page addressed by the offset.
302 */
303int nilfs_mdt_forget_block(struct inode *inode, unsigned long block)
304{
305 pgoff_t index = (pgoff_t)block >>
306 (PAGE_CACHE_SHIFT - inode->i_blkbits);
307 struct page *page;
308 unsigned long first_block;
309 int ret = 0;
310 int still_dirty;
311
312 page = find_lock_page(inode->i_mapping, index);
313 if (!page)
314 return -ENOENT;
315
316 wait_on_page_writeback(page);
317
318 first_block = (unsigned long)index <<
319 (PAGE_CACHE_SHIFT - inode->i_blkbits);
320 if (page_has_buffers(page)) {
321 struct buffer_head *bh;
322
323 bh = nilfs_page_get_nth_block(page, block - first_block);
324 nilfs_forget_buffer(bh);
325 }
326 still_dirty = PageDirty(page);
327 unlock_page(page);
328 page_cache_release(page);
329
330 if (still_dirty ||
331 invalidate_inode_pages2_range(inode->i_mapping, index, index) != 0)
332 ret = -EBUSY;
333 return ret;
334}
335
336/**
337 * nilfs_mdt_mark_block_dirty - mark a block on the meta data file dirty.
338 * @inode: inode of the meta data file
339 * @block: block offset
340 *
341 * Return Value: On success, it returns 0. On error, the following negative
342 * error code is returned.
343 *
344 * %-ENOMEM - Insufficient memory available.
345 *
346 * %-EIO - I/O error
347 *
348 * %-ENOENT - the specified block does not exist (hole block)
Ryusuke Konishi5eb563f2009-04-06 19:01:28 -0700349 */
350int nilfs_mdt_mark_block_dirty(struct inode *inode, unsigned long block)
351{
352 struct buffer_head *bh;
353 int err;
354
Ryusuke Konishib34a6502009-11-14 00:09:47 +0900355 err = nilfs_mdt_read_block(inode, block, 0, &bh);
Ryusuke Konishi5eb563f2009-04-06 19:01:28 -0700356 if (unlikely(err))
357 return err;
Ryusuke Konishi5fc7b142011-05-05 12:56:51 +0900358 mark_buffer_dirty(bh);
Ryusuke Konishi5eb563f2009-04-06 19:01:28 -0700359 nilfs_mdt_mark_dirty(inode);
360 brelse(bh);
361 return 0;
362}
363
364int nilfs_mdt_fetch_dirty(struct inode *inode)
365{
366 struct nilfs_inode_info *ii = NILFS_I(inode);
367
368 if (nilfs_bmap_test_and_clear_dirty(ii->i_bmap)) {
369 set_bit(NILFS_I_DIRTY, &ii->i_state);
370 return 1;
371 }
372 return test_bit(NILFS_I_DIRTY, &ii->i_state);
373}
374
375static int
376nilfs_mdt_write_page(struct page *page, struct writeback_control *wbc)
377{
Vyacheslav Dubeyko8c26c4e2013-04-30 15:27:48 -0700378 struct inode *inode = page->mapping->host;
Ryusuke Konishiebdfed42010-09-06 12:05:43 +0900379 struct super_block *sb;
Ryusuke Konishi5eb563f2009-04-06 19:01:28 -0700380 int err = 0;
381
Vyacheslav Dubeyko8c26c4e2013-04-30 15:27:48 -0700382 if (inode && (inode->i_sb->s_flags & MS_RDONLY)) {
383 /*
384 * It means that filesystem was remounted in read-only
385 * mode because of error or metadata corruption. But we
386 * have dirty pages that try to be flushed in background.
387 * So, here we simply discard this dirty page.
388 */
389 nilfs_clear_dirty_page(page, false);
390 unlock_page(page);
391 return -EROFS;
392 }
393
Ryusuke Konishi5eb563f2009-04-06 19:01:28 -0700394 redirty_page_for_writepage(wbc, page);
395 unlock_page(page);
396
Ryusuke Konishiebdfed42010-09-06 12:05:43 +0900397 if (!inode)
398 return 0;
399
400 sb = inode->i_sb;
Ryusuke Konishi5eb563f2009-04-06 19:01:28 -0700401
402 if (wbc->sync_mode == WB_SYNC_ALL)
403 err = nilfs_construct_segment(sb);
404 else if (wbc->for_reclaim)
405 nilfs_flush_segment(sb, inode->i_ino);
406
Ryusuke Konishi5eb563f2009-04-06 19:01:28 -0700407 return err;
408}
409
410
Alexey Dobriyan7f094102009-09-21 17:01:10 -0700411static const struct address_space_operations def_mdt_aops = {
Ryusuke Konishi5eb563f2009-04-06 19:01:28 -0700412 .writepage = nilfs_mdt_write_page,
413};
414
Alexey Dobriyan6e1d5dc2009-09-21 17:01:11 -0700415static const struct inode_operations def_mdt_iops;
Alexey Dobriyan828c0952009-10-01 15:43:56 -0700416static const struct file_operations def_mdt_fops;
Ryusuke Konishi5eb563f2009-04-06 19:01:28 -0700417
Ryusuke Konishi5e19a992010-08-21 22:01:51 +0900418
Ryusuke Konishif1e89c82010-09-05 12:20:59 +0900419int nilfs_mdt_init(struct inode *inode, gfp_t gfp_mask, size_t objsz)
Ryusuke Konishi5e19a992010-08-21 22:01:51 +0900420{
421 struct nilfs_mdt_info *mi;
422
423 mi = kzalloc(max(sizeof(*mi), objsz), GFP_NOFS);
424 if (!mi)
425 return -ENOMEM;
426
Ryusuke Konishi5e19a992010-08-21 22:01:51 +0900427 init_rwsem(&mi->mi_sem);
428 inode->i_private = mi;
429
430 inode->i_mode = S_IFREG;
431 mapping_set_gfp_mask(inode->i_mapping, gfp_mask);
Ryusuke Konishif1e89c82010-09-05 12:20:59 +0900432
433 inode->i_op = &def_mdt_iops;
434 inode->i_fop = &def_mdt_fops;
435 inode->i_mapping->a_ops = &def_mdt_aops;
Ryusuke Konishi5e19a992010-08-21 22:01:51 +0900436
437 return 0;
438}
439
Ryusuke Konishi5eb563f2009-04-06 19:01:28 -0700440void nilfs_mdt_set_entry_size(struct inode *inode, unsigned entry_size,
441 unsigned header_size)
442{
443 struct nilfs_mdt_info *mi = NILFS_MDT(inode);
444
445 mi->mi_entry_size = entry_size;
446 mi->mi_entries_per_block = (1 << inode->i_blkbits) / entry_size;
447 mi->mi_first_entry_offset = DIV_ROUND_UP(header_size, entry_size);
448}
449
Ryusuke Konishiebdfed42010-09-06 12:05:43 +0900450/**
451 * nilfs_mdt_setup_shadow_map - setup shadow map and bind it to metadata file
452 * @inode: inode of the metadata file
453 * @shadow: shadow mapping
454 */
455int nilfs_mdt_setup_shadow_map(struct inode *inode,
456 struct nilfs_shadow_map *shadow)
457{
458 struct nilfs_mdt_info *mi = NILFS_MDT(inode);
Ryusuke Konishiebdfed42010-09-06 12:05:43 +0900459
460 INIT_LIST_HEAD(&shadow->frozen_buffers);
Miklos Szeredi2aa15892011-02-23 13:49:47 +0100461 address_space_init_once(&shadow->frozen_data);
Christoph Hellwigb83ae6d2015-01-14 10:42:37 +0100462 nilfs_mapping_init(&shadow->frozen_data, inode);
Miklos Szeredi2aa15892011-02-23 13:49:47 +0100463 address_space_init_once(&shadow->frozen_btnodes);
Christoph Hellwigb83ae6d2015-01-14 10:42:37 +0100464 nilfs_mapping_init(&shadow->frozen_btnodes, inode);
Ryusuke Konishiebdfed42010-09-06 12:05:43 +0900465 mi->mi_shadow = shadow;
466 return 0;
467}
468
469/**
470 * nilfs_mdt_save_to_shadow_map - copy bmap and dirty pages to shadow map
471 * @inode: inode of the metadata file
472 */
473int nilfs_mdt_save_to_shadow_map(struct inode *inode)
474{
475 struct nilfs_mdt_info *mi = NILFS_MDT(inode);
476 struct nilfs_inode_info *ii = NILFS_I(inode);
477 struct nilfs_shadow_map *shadow = mi->mi_shadow;
478 int ret;
479
480 ret = nilfs_copy_dirty_pages(&shadow->frozen_data, inode->i_mapping);
481 if (ret)
482 goto out;
483
484 ret = nilfs_copy_dirty_pages(&shadow->frozen_btnodes,
485 &ii->i_btnode_cache);
486 if (ret)
487 goto out;
488
489 nilfs_bmap_save(ii->i_bmap, &shadow->bmap_store);
490 out:
491 return ret;
492}
493
Ryusuke Konishib1f6a4f2010-08-31 11:40:34 +0900494int nilfs_mdt_freeze_buffer(struct inode *inode, struct buffer_head *bh)
495{
496 struct nilfs_shadow_map *shadow = NILFS_MDT(inode)->mi_shadow;
497 struct buffer_head *bh_frozen;
498 struct page *page;
499 int blkbits = inode->i_blkbits;
Ryusuke Konishib1f6a4f2010-08-31 11:40:34 +0900500
501 page = grab_cache_page(&shadow->frozen_data, bh->b_page->index);
502 if (!page)
Ryusuke Konishia7a84472010-12-27 00:03:02 +0900503 return -ENOMEM;
Ryusuke Konishib1f6a4f2010-08-31 11:40:34 +0900504
505 if (!page_has_buffers(page))
506 create_empty_buffers(page, 1 << blkbits, 0);
507
508 bh_frozen = nilfs_page_get_nth_block(page, bh_offset(bh) >> blkbits);
Ryusuke Konishia7a84472010-12-27 00:03:02 +0900509
510 if (!buffer_uptodate(bh_frozen))
511 nilfs_copy_buffer(bh_frozen, bh);
512 if (list_empty(&bh_frozen->b_assoc_buffers)) {
513 list_add_tail(&bh_frozen->b_assoc_buffers,
514 &shadow->frozen_buffers);
515 set_buffer_nilfs_redirected(bh);
516 } else {
517 brelse(bh_frozen); /* already frozen */
Ryusuke Konishib1f6a4f2010-08-31 11:40:34 +0900518 }
Ryusuke Konishia7a84472010-12-27 00:03:02 +0900519
Ryusuke Konishib1f6a4f2010-08-31 11:40:34 +0900520 unlock_page(page);
521 page_cache_release(page);
Ryusuke Konishia7a84472010-12-27 00:03:02 +0900522 return 0;
Ryusuke Konishib1f6a4f2010-08-31 11:40:34 +0900523}
524
525struct buffer_head *
526nilfs_mdt_get_frozen_buffer(struct inode *inode, struct buffer_head *bh)
527{
528 struct nilfs_shadow_map *shadow = NILFS_MDT(inode)->mi_shadow;
529 struct buffer_head *bh_frozen = NULL;
530 struct page *page;
531 int n;
532
533 page = find_lock_page(&shadow->frozen_data, bh->b_page->index);
534 if (page) {
535 if (page_has_buffers(page)) {
536 n = bh_offset(bh) >> inode->i_blkbits;
537 bh_frozen = nilfs_page_get_nth_block(page, n);
538 }
539 unlock_page(page);
540 page_cache_release(page);
541 }
542 return bh_frozen;
543}
544
545static void nilfs_release_frozen_buffers(struct nilfs_shadow_map *shadow)
546{
547 struct list_head *head = &shadow->frozen_buffers;
548 struct buffer_head *bh;
549
550 while (!list_empty(head)) {
551 bh = list_first_entry(head, struct buffer_head,
552 b_assoc_buffers);
553 list_del_init(&bh->b_assoc_buffers);
554 brelse(bh); /* drop ref-count to make it releasable */
555 }
556}
557
Ryusuke Konishiebdfed42010-09-06 12:05:43 +0900558/**
559 * nilfs_mdt_restore_from_shadow_map - restore dirty pages and bmap state
560 * @inode: inode of the metadata file
561 */
562void nilfs_mdt_restore_from_shadow_map(struct inode *inode)
563{
564 struct nilfs_mdt_info *mi = NILFS_MDT(inode);
565 struct nilfs_inode_info *ii = NILFS_I(inode);
566 struct nilfs_shadow_map *shadow = mi->mi_shadow;
567
568 down_write(&mi->mi_sem);
569
570 if (mi->mi_palloc_cache)
571 nilfs_palloc_clear_cache(inode);
572
Vyacheslav Dubeyko8c26c4e2013-04-30 15:27:48 -0700573 nilfs_clear_dirty_pages(inode->i_mapping, true);
Ryusuke Konishiebdfed42010-09-06 12:05:43 +0900574 nilfs_copy_back_pages(inode->i_mapping, &shadow->frozen_data);
575
Vyacheslav Dubeyko8c26c4e2013-04-30 15:27:48 -0700576 nilfs_clear_dirty_pages(&ii->i_btnode_cache, true);
Ryusuke Konishiebdfed42010-09-06 12:05:43 +0900577 nilfs_copy_back_pages(&ii->i_btnode_cache, &shadow->frozen_btnodes);
578
579 nilfs_bmap_restore(ii->i_bmap, &shadow->bmap_store);
580
581 up_write(&mi->mi_sem);
582}
583
584/**
585 * nilfs_mdt_clear_shadow_map - truncate pages in shadow map caches
586 * @inode: inode of the metadata file
587 */
588void nilfs_mdt_clear_shadow_map(struct inode *inode)
589{
590 struct nilfs_mdt_info *mi = NILFS_MDT(inode);
591 struct nilfs_shadow_map *shadow = mi->mi_shadow;
592
593 down_write(&mi->mi_sem);
Ryusuke Konishib1f6a4f2010-08-31 11:40:34 +0900594 nilfs_release_frozen_buffers(shadow);
Ryusuke Konishiebdfed42010-09-06 12:05:43 +0900595 truncate_inode_pages(&shadow->frozen_data, 0);
596 truncate_inode_pages(&shadow->frozen_btnodes, 0);
597 up_write(&mi->mi_sem);
598}