1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Meta data file for NILFS
4  *
5  * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.
6  *
7  * Written by Ryusuke Konishi.
8  */
9 
10 #include <linux/buffer_head.h>
11 #include <linux/mpage.h>
12 #include <linux/mm.h>
13 #include <linux/writeback.h>
14 #include <linux/backing-dev.h>
15 #include <linux/swap.h>
16 #include <linux/slab.h>
17 #include "nilfs.h"
18 #include "btnode.h"
19 #include "segment.h"
20 #include "page.h"
21 #include "mdt.h"
22 #include "alloc.h"		/* nilfs_palloc_destroy_cache() */
23 
24 #include <trace/events/nilfs2.h>
25 
26 #define NILFS_MDT_MAX_RA_BLOCKS		(16 - 1)
27 
28 
29 static int
nilfs_mdt_insert_new_block(struct inode * inode,unsigned long block,struct buffer_head * bh,void (* init_block)(struct inode *,struct buffer_head *,void *))30 nilfs_mdt_insert_new_block(struct inode *inode, unsigned long block,
31 			   struct buffer_head *bh,
32 			   void (*init_block)(struct inode *,
33 					      struct buffer_head *, void *))
34 {
35 	struct nilfs_inode_info *ii = NILFS_I(inode);
36 	void *kaddr;
37 	int ret;
38 
39 	/* Caller exclude read accesses using page lock */
40 
41 	/* set_buffer_new(bh); */
42 	bh->b_blocknr = 0;
43 
44 	ret = nilfs_bmap_insert(ii->i_bmap, block, (unsigned long)bh);
45 	if (unlikely(ret))
46 		return ret;
47 
48 	set_buffer_mapped(bh);
49 
50 	kaddr = kmap_atomic(bh->b_page);
51 	memset(kaddr + bh_offset(bh), 0, i_blocksize(inode));
52 	if (init_block)
53 		init_block(inode, bh, kaddr);
54 	flush_dcache_page(bh->b_page);
55 	kunmap_atomic(kaddr);
56 
57 	set_buffer_uptodate(bh);
58 	mark_buffer_dirty(bh);
59 	nilfs_mdt_mark_dirty(inode);
60 
61 	trace_nilfs2_mdt_insert_new_block(inode, inode->i_ino, block);
62 
63 	return 0;
64 }
65 
nilfs_mdt_create_block(struct inode * inode,unsigned long block,struct buffer_head ** out_bh,void (* init_block)(struct inode *,struct buffer_head *,void *))66 static int nilfs_mdt_create_block(struct inode *inode, unsigned long block,
67 				  struct buffer_head **out_bh,
68 				  void (*init_block)(struct inode *,
69 						     struct buffer_head *,
70 						     void *))
71 {
72 	struct super_block *sb = inode->i_sb;
73 	struct nilfs_transaction_info ti;
74 	struct buffer_head *bh;
75 	int err;
76 
77 	nilfs_transaction_begin(sb, &ti, 0);
78 
79 	err = -ENOMEM;
80 	bh = nilfs_grab_buffer(inode, inode->i_mapping, block, 0);
81 	if (unlikely(!bh))
82 		goto failed_unlock;
83 
84 	err = -EEXIST;
85 	if (buffer_uptodate(bh))
86 		goto failed_bh;
87 
88 	wait_on_buffer(bh);
89 	if (buffer_uptodate(bh))
90 		goto failed_bh;
91 
92 	bh->b_bdev = sb->s_bdev;
93 	err = nilfs_mdt_insert_new_block(inode, block, bh, init_block);
94 	if (likely(!err)) {
95 		get_bh(bh);
96 		*out_bh = bh;
97 	}
98 
99  failed_bh:
100 	unlock_page(bh->b_page);
101 	put_page(bh->b_page);
102 	brelse(bh);
103 
104  failed_unlock:
105 	if (likely(!err))
106 		err = nilfs_transaction_commit(sb);
107 	else
108 		nilfs_transaction_abort(sb);
109 
110 	return err;
111 }
112 
113 static int
nilfs_mdt_submit_block(struct inode * inode,unsigned long blkoff,blk_opf_t opf,struct buffer_head ** out_bh)114 nilfs_mdt_submit_block(struct inode *inode, unsigned long blkoff, blk_opf_t opf,
115 		       struct buffer_head **out_bh)
116 {
117 	struct buffer_head *bh;
118 	__u64 blknum = 0;
119 	int ret = -ENOMEM;
120 
121 	bh = nilfs_grab_buffer(inode, inode->i_mapping, blkoff, 0);
122 	if (unlikely(!bh))
123 		goto failed;
124 
125 	ret = -EEXIST; /* internal code */
126 	if (buffer_uptodate(bh))
127 		goto out;
128 
129 	if (opf & REQ_RAHEAD) {
130 		if (!trylock_buffer(bh)) {
131 			ret = -EBUSY;
132 			goto failed_bh;
133 		}
134 	} else /* opf == REQ_OP_READ */
135 		lock_buffer(bh);
136 
137 	if (buffer_uptodate(bh)) {
138 		unlock_buffer(bh);
139 		goto out;
140 	}
141 
142 	ret = nilfs_bmap_lookup(NILFS_I(inode)->i_bmap, blkoff, &blknum);
143 	if (unlikely(ret)) {
144 		unlock_buffer(bh);
145 		goto failed_bh;
146 	}
147 	map_bh(bh, inode->i_sb, (sector_t)blknum);
148 
149 	bh->b_end_io = end_buffer_read_sync;
150 	get_bh(bh);
151 	submit_bh(opf, bh);
152 	ret = 0;
153 
154 	trace_nilfs2_mdt_submit_block(inode, inode->i_ino, blkoff,
155 				      opf & REQ_OP_MASK);
156  out:
157 	get_bh(bh);
158 	*out_bh = bh;
159 
160  failed_bh:
161 	unlock_page(bh->b_page);
162 	put_page(bh->b_page);
163 	brelse(bh);
164  failed:
165 	return ret;
166 }
167 
nilfs_mdt_read_block(struct inode * inode,unsigned long block,int readahead,struct buffer_head ** out_bh)168 static int nilfs_mdt_read_block(struct inode *inode, unsigned long block,
169 				int readahead, struct buffer_head **out_bh)
170 {
171 	struct buffer_head *first_bh, *bh;
172 	unsigned long blkoff;
173 	int i, nr_ra_blocks = NILFS_MDT_MAX_RA_BLOCKS;
174 	int err;
175 
176 	err = nilfs_mdt_submit_block(inode, block, REQ_OP_READ, &first_bh);
177 	if (err == -EEXIST) /* internal code */
178 		goto out;
179 
180 	if (unlikely(err))
181 		goto failed;
182 
183 	if (readahead) {
184 		blkoff = block + 1;
185 		for (i = 0; i < nr_ra_blocks; i++, blkoff++) {
186 			err = nilfs_mdt_submit_block(inode, blkoff,
187 						REQ_OP_READ | REQ_RAHEAD, &bh);
188 			if (likely(!err || err == -EEXIST))
189 				brelse(bh);
190 			else if (err != -EBUSY)
191 				break;
192 				/* abort readahead if bmap lookup failed */
193 			if (!buffer_locked(first_bh))
194 				goto out_no_wait;
195 		}
196 	}
197 
198 	wait_on_buffer(first_bh);
199 
200  out_no_wait:
201 	err = -EIO;
202 	if (!buffer_uptodate(first_bh)) {
203 		nilfs_err(inode->i_sb,
204 			  "I/O error reading meta-data file (ino=%lu, block-offset=%lu)",
205 			  inode->i_ino, block);
206 		goto failed_bh;
207 	}
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  *
240  * %-EROFS - Read only filesystem (for create mode)
241  */
nilfs_mdt_get_block(struct inode * inode,unsigned long blkoff,int create,void (* init_block)(struct inode *,struct buffer_head *,void *),struct buffer_head ** out_bh)242 int 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:
251 	ret = nilfs_mdt_read_block(inode, blkoff, !create, out_bh);
252 	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_find_block - find and get a buffer on meta data file.
265  * @inode: inode of the meta data file
266  * @start: start block offset (inclusive)
267  * @end: end block offset (inclusive)
268  * @blkoff: block offset
269  * @out_bh: place to store a pointer to buffer_head struct
270  *
271  * nilfs_mdt_find_block() looks up an existing block in range of
272  * [@start, @end] and stores pointer to a buffer head of the block to
273  * @out_bh, and block offset to @blkoff, respectively.  @out_bh and
274  * @blkoff are substituted only when zero is returned.
275  *
276  * Return Value: On success, it returns 0. On error, the following negative
277  * error code is returned.
278  *
279  * %-ENOMEM - Insufficient memory available.
280  *
281  * %-EIO - I/O error
282  *
283  * %-ENOENT - no block was found in the range
284  */
nilfs_mdt_find_block(struct inode * inode,unsigned long start,unsigned long end,unsigned long * blkoff,struct buffer_head ** out_bh)285 int nilfs_mdt_find_block(struct inode *inode, unsigned long start,
286 			 unsigned long end, unsigned long *blkoff,
287 			 struct buffer_head **out_bh)
288 {
289 	__u64 next;
290 	int ret;
291 
292 	if (unlikely(start > end))
293 		return -ENOENT;
294 
295 	ret = nilfs_mdt_read_block(inode, start, true, out_bh);
296 	if (!ret) {
297 		*blkoff = start;
298 		goto out;
299 	}
300 	if (unlikely(ret != -ENOENT || start == ULONG_MAX))
301 		goto out;
302 
303 	ret = nilfs_bmap_seek_key(NILFS_I(inode)->i_bmap, start + 1, &next);
304 	if (!ret) {
305 		if (next <= end) {
306 			ret = nilfs_mdt_read_block(inode, next, true, out_bh);
307 			if (!ret)
308 				*blkoff = next;
309 		} else {
310 			ret = -ENOENT;
311 		}
312 	}
313 out:
314 	return ret;
315 }
316 
317 /**
318  * nilfs_mdt_delete_block - make a hole on the meta data file.
319  * @inode: inode of the meta data file
320  * @block: block offset
321  *
322  * Return Value: On success, zero is returned.
323  * On error, one of the following negative error code is returned.
324  *
325  * %-ENOMEM - Insufficient memory available.
326  *
327  * %-EIO - I/O error
328  */
nilfs_mdt_delete_block(struct inode * inode,unsigned long block)329 int nilfs_mdt_delete_block(struct inode *inode, unsigned long block)
330 {
331 	struct nilfs_inode_info *ii = NILFS_I(inode);
332 	int err;
333 
334 	err = nilfs_bmap_delete(ii->i_bmap, block);
335 	if (!err || err == -ENOENT) {
336 		nilfs_mdt_mark_dirty(inode);
337 		nilfs_mdt_forget_block(inode, block);
338 	}
339 	return err;
340 }
341 
342 /**
343  * nilfs_mdt_forget_block - discard dirty state and try to remove the page
344  * @inode: inode of the meta data file
345  * @block: block offset
346  *
347  * nilfs_mdt_forget_block() clears a dirty flag of the specified buffer, and
348  * tries to release the page including the buffer from a page cache.
349  *
350  * Return Value: On success, 0 is returned. On error, one of the following
351  * negative error code is returned.
352  *
353  * %-EBUSY - page has an active buffer.
354  *
355  * %-ENOENT - page cache has no page addressed by the offset.
356  */
nilfs_mdt_forget_block(struct inode * inode,unsigned long block)357 int nilfs_mdt_forget_block(struct inode *inode, unsigned long block)
358 {
359 	pgoff_t index = (pgoff_t)block >>
360 		(PAGE_SHIFT - inode->i_blkbits);
361 	struct page *page;
362 	unsigned long first_block;
363 	int ret = 0;
364 	int still_dirty;
365 
366 	page = find_lock_page(inode->i_mapping, index);
367 	if (!page)
368 		return -ENOENT;
369 
370 	wait_on_page_writeback(page);
371 
372 	first_block = (unsigned long)index <<
373 		(PAGE_SHIFT - inode->i_blkbits);
374 	if (page_has_buffers(page)) {
375 		struct buffer_head *bh;
376 
377 		bh = nilfs_page_get_nth_block(page, block - first_block);
378 		nilfs_forget_buffer(bh);
379 	}
380 	still_dirty = PageDirty(page);
381 	unlock_page(page);
382 	put_page(page);
383 
384 	if (still_dirty ||
385 	    invalidate_inode_pages2_range(inode->i_mapping, index, index) != 0)
386 		ret = -EBUSY;
387 	return ret;
388 }
389 
nilfs_mdt_fetch_dirty(struct inode * inode)390 int nilfs_mdt_fetch_dirty(struct inode *inode)
391 {
392 	struct nilfs_inode_info *ii = NILFS_I(inode);
393 
394 	if (nilfs_bmap_test_and_clear_dirty(ii->i_bmap)) {
395 		set_bit(NILFS_I_DIRTY, &ii->i_state);
396 		return 1;
397 	}
398 	return test_bit(NILFS_I_DIRTY, &ii->i_state);
399 }
400 
401 static int
nilfs_mdt_write_page(struct page * page,struct writeback_control * wbc)402 nilfs_mdt_write_page(struct page *page, struct writeback_control *wbc)
403 {
404 	struct inode *inode = page->mapping->host;
405 	struct super_block *sb;
406 	int err = 0;
407 
408 	if (inode && sb_rdonly(inode->i_sb)) {
409 		/*
410 		 * It means that filesystem was remounted in read-only
411 		 * mode because of error or metadata corruption. But we
412 		 * have dirty pages that try to be flushed in background.
413 		 * So, here we simply discard this dirty page.
414 		 */
415 		nilfs_clear_dirty_page(page, false);
416 		unlock_page(page);
417 		return -EROFS;
418 	}
419 
420 	redirty_page_for_writepage(wbc, page);
421 	unlock_page(page);
422 
423 	if (!inode)
424 		return 0;
425 
426 	sb = inode->i_sb;
427 
428 	if (wbc->sync_mode == WB_SYNC_ALL)
429 		err = nilfs_construct_segment(sb);
430 	else if (wbc->for_reclaim)
431 		nilfs_flush_segment(sb, inode->i_ino);
432 
433 	return err;
434 }
435 
436 
437 static const struct address_space_operations def_mdt_aops = {
438 	.dirty_folio		= block_dirty_folio,
439 	.invalidate_folio	= block_invalidate_folio,
440 	.writepage		= nilfs_mdt_write_page,
441 };
442 
443 static const struct inode_operations def_mdt_iops;
444 static const struct file_operations def_mdt_fops;
445 
446 
nilfs_mdt_init(struct inode * inode,gfp_t gfp_mask,size_t objsz)447 int nilfs_mdt_init(struct inode *inode, gfp_t gfp_mask, size_t objsz)
448 {
449 	struct nilfs_mdt_info *mi;
450 
451 	mi = kzalloc(max(sizeof(*mi), objsz), GFP_NOFS);
452 	if (!mi)
453 		return -ENOMEM;
454 
455 	init_rwsem(&mi->mi_sem);
456 	inode->i_private = mi;
457 
458 	inode->i_mode = S_IFREG;
459 	mapping_set_gfp_mask(inode->i_mapping, gfp_mask);
460 
461 	inode->i_op = &def_mdt_iops;
462 	inode->i_fop = &def_mdt_fops;
463 	inode->i_mapping->a_ops = &def_mdt_aops;
464 
465 	return 0;
466 }
467 
468 /**
469  * nilfs_mdt_clear - do cleanup for the metadata file
470  * @inode: inode of the metadata file
471  */
nilfs_mdt_clear(struct inode * inode)472 void nilfs_mdt_clear(struct inode *inode)
473 {
474 	struct nilfs_mdt_info *mdi = NILFS_MDT(inode);
475 	struct nilfs_shadow_map *shadow = mdi->mi_shadow;
476 
477 	if (mdi->mi_palloc_cache)
478 		nilfs_palloc_destroy_cache(inode);
479 
480 	if (shadow) {
481 		struct inode *s_inode = shadow->inode;
482 
483 		shadow->inode = NULL;
484 		iput(s_inode);
485 		mdi->mi_shadow = NULL;
486 	}
487 }
488 
489 /**
490  * nilfs_mdt_destroy - release resources used by the metadata file
491  * @inode: inode of the metadata file
492  */
nilfs_mdt_destroy(struct inode * inode)493 void nilfs_mdt_destroy(struct inode *inode)
494 {
495 	struct nilfs_mdt_info *mdi = NILFS_MDT(inode);
496 
497 	kfree(mdi->mi_bgl); /* kfree(NULL) is safe */
498 	kfree(mdi);
499 }
500 
nilfs_mdt_set_entry_size(struct inode * inode,unsigned int entry_size,unsigned int header_size)501 void nilfs_mdt_set_entry_size(struct inode *inode, unsigned int entry_size,
502 			      unsigned int header_size)
503 {
504 	struct nilfs_mdt_info *mi = NILFS_MDT(inode);
505 
506 	mi->mi_entry_size = entry_size;
507 	mi->mi_entries_per_block = i_blocksize(inode) / entry_size;
508 	mi->mi_first_entry_offset = DIV_ROUND_UP(header_size, entry_size);
509 }
510 
511 /**
512  * nilfs_mdt_setup_shadow_map - setup shadow map and bind it to metadata file
513  * @inode: inode of the metadata file
514  * @shadow: shadow mapping
515  */
nilfs_mdt_setup_shadow_map(struct inode * inode,struct nilfs_shadow_map * shadow)516 int nilfs_mdt_setup_shadow_map(struct inode *inode,
517 			       struct nilfs_shadow_map *shadow)
518 {
519 	struct nilfs_mdt_info *mi = NILFS_MDT(inode);
520 	struct inode *s_inode;
521 
522 	INIT_LIST_HEAD(&shadow->frozen_buffers);
523 
524 	s_inode = nilfs_iget_for_shadow(inode);
525 	if (IS_ERR(s_inode))
526 		return PTR_ERR(s_inode);
527 
528 	shadow->inode = s_inode;
529 	mi->mi_shadow = shadow;
530 	return 0;
531 }
532 
533 /**
534  * nilfs_mdt_save_to_shadow_map - copy bmap and dirty pages to shadow map
535  * @inode: inode of the metadata file
536  */
nilfs_mdt_save_to_shadow_map(struct inode * inode)537 int nilfs_mdt_save_to_shadow_map(struct inode *inode)
538 {
539 	struct nilfs_mdt_info *mi = NILFS_MDT(inode);
540 	struct nilfs_inode_info *ii = NILFS_I(inode);
541 	struct nilfs_shadow_map *shadow = mi->mi_shadow;
542 	struct inode *s_inode = shadow->inode;
543 	int ret;
544 
545 	ret = nilfs_copy_dirty_pages(s_inode->i_mapping, inode->i_mapping);
546 	if (ret)
547 		goto out;
548 
549 	ret = nilfs_copy_dirty_pages(NILFS_I(s_inode)->i_assoc_inode->i_mapping,
550 				     ii->i_assoc_inode->i_mapping);
551 	if (ret)
552 		goto out;
553 
554 	nilfs_bmap_save(ii->i_bmap, &shadow->bmap_store);
555  out:
556 	return ret;
557 }
558 
nilfs_mdt_freeze_buffer(struct inode * inode,struct buffer_head * bh)559 int nilfs_mdt_freeze_buffer(struct inode *inode, struct buffer_head *bh)
560 {
561 	struct nilfs_shadow_map *shadow = NILFS_MDT(inode)->mi_shadow;
562 	struct buffer_head *bh_frozen;
563 	struct page *page;
564 	int blkbits = inode->i_blkbits;
565 
566 	page = grab_cache_page(shadow->inode->i_mapping, bh->b_page->index);
567 	if (!page)
568 		return -ENOMEM;
569 
570 	if (!page_has_buffers(page))
571 		create_empty_buffers(page, 1 << blkbits, 0);
572 
573 	bh_frozen = nilfs_page_get_nth_block(page, bh_offset(bh) >> blkbits);
574 
575 	if (!buffer_uptodate(bh_frozen))
576 		nilfs_copy_buffer(bh_frozen, bh);
577 	if (list_empty(&bh_frozen->b_assoc_buffers)) {
578 		list_add_tail(&bh_frozen->b_assoc_buffers,
579 			      &shadow->frozen_buffers);
580 		set_buffer_nilfs_redirected(bh);
581 	} else {
582 		brelse(bh_frozen); /* already frozen */
583 	}
584 
585 	unlock_page(page);
586 	put_page(page);
587 	return 0;
588 }
589 
590 struct buffer_head *
nilfs_mdt_get_frozen_buffer(struct inode * inode,struct buffer_head * bh)591 nilfs_mdt_get_frozen_buffer(struct inode *inode, struct buffer_head *bh)
592 {
593 	struct nilfs_shadow_map *shadow = NILFS_MDT(inode)->mi_shadow;
594 	struct buffer_head *bh_frozen = NULL;
595 	struct page *page;
596 	int n;
597 
598 	page = find_lock_page(shadow->inode->i_mapping, bh->b_page->index);
599 	if (page) {
600 		if (page_has_buffers(page)) {
601 			n = bh_offset(bh) >> inode->i_blkbits;
602 			bh_frozen = nilfs_page_get_nth_block(page, n);
603 		}
604 		unlock_page(page);
605 		put_page(page);
606 	}
607 	return bh_frozen;
608 }
609 
nilfs_release_frozen_buffers(struct nilfs_shadow_map * shadow)610 static void nilfs_release_frozen_buffers(struct nilfs_shadow_map *shadow)
611 {
612 	struct list_head *head = &shadow->frozen_buffers;
613 	struct buffer_head *bh;
614 
615 	while (!list_empty(head)) {
616 		bh = list_first_entry(head, struct buffer_head,
617 				      b_assoc_buffers);
618 		list_del_init(&bh->b_assoc_buffers);
619 		brelse(bh); /* drop ref-count to make it releasable */
620 	}
621 }
622 
623 /**
624  * nilfs_mdt_restore_from_shadow_map - restore dirty pages and bmap state
625  * @inode: inode of the metadata file
626  */
nilfs_mdt_restore_from_shadow_map(struct inode * inode)627 void nilfs_mdt_restore_from_shadow_map(struct inode *inode)
628 {
629 	struct nilfs_mdt_info *mi = NILFS_MDT(inode);
630 	struct nilfs_inode_info *ii = NILFS_I(inode);
631 	struct nilfs_shadow_map *shadow = mi->mi_shadow;
632 
633 	down_write(&mi->mi_sem);
634 
635 	if (mi->mi_palloc_cache)
636 		nilfs_palloc_clear_cache(inode);
637 
638 	nilfs_clear_dirty_pages(inode->i_mapping, true);
639 	nilfs_copy_back_pages(inode->i_mapping, shadow->inode->i_mapping);
640 
641 	nilfs_clear_dirty_pages(ii->i_assoc_inode->i_mapping, true);
642 	nilfs_copy_back_pages(ii->i_assoc_inode->i_mapping,
643 			      NILFS_I(shadow->inode)->i_assoc_inode->i_mapping);
644 
645 	nilfs_bmap_restore(ii->i_bmap, &shadow->bmap_store);
646 
647 	up_write(&mi->mi_sem);
648 }
649 
650 /**
651  * nilfs_mdt_clear_shadow_map - truncate pages in shadow map caches
652  * @inode: inode of the metadata file
653  */
nilfs_mdt_clear_shadow_map(struct inode * inode)654 void nilfs_mdt_clear_shadow_map(struct inode *inode)
655 {
656 	struct nilfs_mdt_info *mi = NILFS_MDT(inode);
657 	struct nilfs_shadow_map *shadow = mi->mi_shadow;
658 	struct inode *shadow_btnc_inode = NILFS_I(shadow->inode)->i_assoc_inode;
659 
660 	down_write(&mi->mi_sem);
661 	nilfs_release_frozen_buffers(shadow);
662 	truncate_inode_pages(shadow->inode->i_mapping, 0);
663 	truncate_inode_pages(shadow_btnc_inode->i_mapping, 0);
664 	up_write(&mi->mi_sem);
665 }
666