xref: /openbmc/linux/fs/nilfs2/inode.c (revision 7dd65feb)
1 /*
2  * inode.c - NILFS inode operations.
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 
24 #include <linux/buffer_head.h>
25 #include <linux/mpage.h>
26 #include <linux/writeback.h>
27 #include <linux/uio.h>
28 #include "nilfs.h"
29 #include "segment.h"
30 #include "page.h"
31 #include "mdt.h"
32 #include "cpfile.h"
33 #include "ifile.h"
34 
35 
36 /**
37  * nilfs_get_block() - get a file block on the filesystem (callback function)
38  * @inode - inode struct of the target file
39  * @blkoff - file block number
40  * @bh_result - buffer head to be mapped on
41  * @create - indicate whether allocating the block or not when it has not
42  *      been allocated yet.
43  *
44  * This function does not issue actual read request of the specified data
45  * block. It is done by VFS.
46  */
47 int nilfs_get_block(struct inode *inode, sector_t blkoff,
48 		    struct buffer_head *bh_result, int create)
49 {
50 	struct nilfs_inode_info *ii = NILFS_I(inode);
51 	__u64 blknum = 0;
52 	int err = 0, ret;
53 	struct inode *dat = nilfs_dat_inode(NILFS_I_NILFS(inode));
54 	unsigned maxblocks = bh_result->b_size >> inode->i_blkbits;
55 
56 	down_read(&NILFS_MDT(dat)->mi_sem);
57 	ret = nilfs_bmap_lookup_contig(ii->i_bmap, blkoff, &blknum, maxblocks);
58 	up_read(&NILFS_MDT(dat)->mi_sem);
59 	if (ret >= 0) {	/* found */
60 		map_bh(bh_result, inode->i_sb, blknum);
61 		if (ret > 0)
62 			bh_result->b_size = (ret << inode->i_blkbits);
63 		goto out;
64 	}
65 	/* data block was not found */
66 	if (ret == -ENOENT && create) {
67 		struct nilfs_transaction_info ti;
68 
69 		bh_result->b_blocknr = 0;
70 		err = nilfs_transaction_begin(inode->i_sb, &ti, 1);
71 		if (unlikely(err))
72 			goto out;
73 		err = nilfs_bmap_insert(ii->i_bmap, (unsigned long)blkoff,
74 					(unsigned long)bh_result);
75 		if (unlikely(err != 0)) {
76 			if (err == -EEXIST) {
77 				/*
78 				 * The get_block() function could be called
79 				 * from multiple callers for an inode.
80 				 * However, the page having this block must
81 				 * be locked in this case.
82 				 */
83 				printk(KERN_WARNING
84 				       "nilfs_get_block: a race condition "
85 				       "while inserting a data block. "
86 				       "(inode number=%lu, file block "
87 				       "offset=%llu)\n",
88 				       inode->i_ino,
89 				       (unsigned long long)blkoff);
90 				err = 0;
91 			} else if (err == -EINVAL) {
92 				nilfs_error(inode->i_sb, __func__,
93 					    "broken bmap (inode=%lu)\n",
94 					    inode->i_ino);
95 				err = -EIO;
96 			}
97 			nilfs_transaction_abort(inode->i_sb);
98 			goto out;
99 		}
100 		nilfs_mark_inode_dirty(inode);
101 		nilfs_transaction_commit(inode->i_sb); /* never fails */
102 		/* Error handling should be detailed */
103 		set_buffer_new(bh_result);
104 		map_bh(bh_result, inode->i_sb, 0); /* dbn must be changed
105 						      to proper value */
106 	} else if (ret == -ENOENT) {
107 		/* not found is not error (e.g. hole); must return without
108 		   the mapped state flag. */
109 		;
110 	} else {
111 		err = ret;
112 	}
113 
114  out:
115 	return err;
116 }
117 
118 /**
119  * nilfs_readpage() - implement readpage() method of nilfs_aops {}
120  * address_space_operations.
121  * @file - file struct of the file to be read
122  * @page - the page to be read
123  */
124 static int nilfs_readpage(struct file *file, struct page *page)
125 {
126 	return mpage_readpage(page, nilfs_get_block);
127 }
128 
129 /**
130  * nilfs_readpages() - implement readpages() method of nilfs_aops {}
131  * address_space_operations.
132  * @file - file struct of the file to be read
133  * @mapping - address_space struct used for reading multiple pages
134  * @pages - the pages to be read
135  * @nr_pages - number of pages to be read
136  */
137 static int nilfs_readpages(struct file *file, struct address_space *mapping,
138 			   struct list_head *pages, unsigned nr_pages)
139 {
140 	return mpage_readpages(mapping, pages, nr_pages, nilfs_get_block);
141 }
142 
143 static int nilfs_writepages(struct address_space *mapping,
144 			    struct writeback_control *wbc)
145 {
146 	struct inode *inode = mapping->host;
147 	int err = 0;
148 
149 	if (wbc->sync_mode == WB_SYNC_ALL)
150 		err = nilfs_construct_dsync_segment(inode->i_sb, inode,
151 						    wbc->range_start,
152 						    wbc->range_end);
153 	return err;
154 }
155 
156 static int nilfs_writepage(struct page *page, struct writeback_control *wbc)
157 {
158 	struct inode *inode = page->mapping->host;
159 	int err;
160 
161 	redirty_page_for_writepage(wbc, page);
162 	unlock_page(page);
163 
164 	if (wbc->sync_mode == WB_SYNC_ALL) {
165 		err = nilfs_construct_segment(inode->i_sb);
166 		if (unlikely(err))
167 			return err;
168 	} else if (wbc->for_reclaim)
169 		nilfs_flush_segment(inode->i_sb, inode->i_ino);
170 
171 	return 0;
172 }
173 
174 static int nilfs_set_page_dirty(struct page *page)
175 {
176 	int ret = __set_page_dirty_buffers(page);
177 
178 	if (ret) {
179 		struct inode *inode = page->mapping->host;
180 		struct nilfs_sb_info *sbi = NILFS_SB(inode->i_sb);
181 		unsigned nr_dirty = 1 << (PAGE_SHIFT - inode->i_blkbits);
182 
183 		nilfs_set_file_dirty(sbi, inode, nr_dirty);
184 	}
185 	return ret;
186 }
187 
188 static int nilfs_write_begin(struct file *file, struct address_space *mapping,
189 			     loff_t pos, unsigned len, unsigned flags,
190 			     struct page **pagep, void **fsdata)
191 
192 {
193 	struct inode *inode = mapping->host;
194 	int err = nilfs_transaction_begin(inode->i_sb, NULL, 1);
195 
196 	if (unlikely(err))
197 		return err;
198 
199 	*pagep = NULL;
200 	err = block_write_begin(file, mapping, pos, len, flags, pagep,
201 				fsdata, nilfs_get_block);
202 	if (unlikely(err))
203 		nilfs_transaction_abort(inode->i_sb);
204 	return err;
205 }
206 
207 static int nilfs_write_end(struct file *file, struct address_space *mapping,
208 			   loff_t pos, unsigned len, unsigned copied,
209 			   struct page *page, void *fsdata)
210 {
211 	struct inode *inode = mapping->host;
212 	unsigned start = pos & (PAGE_CACHE_SIZE - 1);
213 	unsigned nr_dirty;
214 	int err;
215 
216 	nr_dirty = nilfs_page_count_clean_buffers(page, start,
217 						  start + copied);
218 	copied = generic_write_end(file, mapping, pos, len, copied, page,
219 				   fsdata);
220 	nilfs_set_file_dirty(NILFS_SB(inode->i_sb), inode, nr_dirty);
221 	err = nilfs_transaction_commit(inode->i_sb);
222 	return err ? : copied;
223 }
224 
225 static ssize_t
226 nilfs_direct_IO(int rw, struct kiocb *iocb, const struct iovec *iov,
227 		loff_t offset, unsigned long nr_segs)
228 {
229 	struct file *file = iocb->ki_filp;
230 	struct inode *inode = file->f_mapping->host;
231 	ssize_t size;
232 
233 	if (rw == WRITE)
234 		return 0;
235 
236 	/* Needs synchronization with the cleaner */
237 	size = blockdev_direct_IO(rw, iocb, inode, inode->i_sb->s_bdev, iov,
238 				  offset, nr_segs, nilfs_get_block, NULL);
239 	return size;
240 }
241 
242 const struct address_space_operations nilfs_aops = {
243 	.writepage		= nilfs_writepage,
244 	.readpage		= nilfs_readpage,
245 	.sync_page		= block_sync_page,
246 	.writepages		= nilfs_writepages,
247 	.set_page_dirty		= nilfs_set_page_dirty,
248 	.readpages		= nilfs_readpages,
249 	.write_begin		= nilfs_write_begin,
250 	.write_end		= nilfs_write_end,
251 	/* .releasepage		= nilfs_releasepage, */
252 	.invalidatepage		= block_invalidatepage,
253 	.direct_IO		= nilfs_direct_IO,
254 	.is_partially_uptodate  = block_is_partially_uptodate,
255 };
256 
257 struct inode *nilfs_new_inode(struct inode *dir, int mode)
258 {
259 	struct super_block *sb = dir->i_sb;
260 	struct nilfs_sb_info *sbi = NILFS_SB(sb);
261 	struct inode *inode;
262 	struct nilfs_inode_info *ii;
263 	int err = -ENOMEM;
264 	ino_t ino;
265 
266 	inode = new_inode(sb);
267 	if (unlikely(!inode))
268 		goto failed;
269 
270 	mapping_set_gfp_mask(inode->i_mapping,
271 			     mapping_gfp_mask(inode->i_mapping) & ~__GFP_FS);
272 
273 	ii = NILFS_I(inode);
274 	ii->i_state = 1 << NILFS_I_NEW;
275 
276 	err = nilfs_ifile_create_inode(sbi->s_ifile, &ino, &ii->i_bh);
277 	if (unlikely(err))
278 		goto failed_ifile_create_inode;
279 	/* reference count of i_bh inherits from nilfs_mdt_read_block() */
280 
281 	atomic_inc(&sbi->s_inodes_count);
282 
283 	inode->i_uid = current_fsuid();
284 	if (dir->i_mode & S_ISGID) {
285 		inode->i_gid = dir->i_gid;
286 		if (S_ISDIR(mode))
287 			mode |= S_ISGID;
288 	} else
289 		inode->i_gid = current_fsgid();
290 
291 	inode->i_mode = mode;
292 	inode->i_ino = ino;
293 	inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
294 
295 	if (S_ISREG(mode) || S_ISDIR(mode) || S_ISLNK(mode)) {
296 		err = nilfs_bmap_read(ii->i_bmap, NULL);
297 		if (err < 0)
298 			goto failed_bmap;
299 
300 		set_bit(NILFS_I_BMAP, &ii->i_state);
301 		/* No lock is needed; iget() ensures it. */
302 	}
303 
304 	ii->i_flags = NILFS_I(dir)->i_flags;
305 	if (S_ISLNK(mode))
306 		ii->i_flags &= ~(NILFS_IMMUTABLE_FL | NILFS_APPEND_FL);
307 	if (!S_ISDIR(mode))
308 		ii->i_flags &= ~NILFS_DIRSYNC_FL;
309 
310 	/* ii->i_file_acl = 0; */
311 	/* ii->i_dir_acl = 0; */
312 	ii->i_dir_start_lookup = 0;
313 	ii->i_cno = 0;
314 	nilfs_set_inode_flags(inode);
315 	spin_lock(&sbi->s_next_gen_lock);
316 	inode->i_generation = sbi->s_next_generation++;
317 	spin_unlock(&sbi->s_next_gen_lock);
318 	insert_inode_hash(inode);
319 
320 	err = nilfs_init_acl(inode, dir);
321 	if (unlikely(err))
322 		goto failed_acl; /* never occur. When supporting
323 				    nilfs_init_acl(), proper cancellation of
324 				    above jobs should be considered */
325 
326 	return inode;
327 
328  failed_acl:
329  failed_bmap:
330 	inode->i_nlink = 0;
331 	iput(inode);  /* raw_inode will be deleted through
332 			 generic_delete_inode() */
333 	goto failed;
334 
335  failed_ifile_create_inode:
336 	make_bad_inode(inode);
337 	iput(inode);  /* if i_nlink == 1, generic_forget_inode() will be
338 			 called */
339  failed:
340 	return ERR_PTR(err);
341 }
342 
343 void nilfs_free_inode(struct inode *inode)
344 {
345 	struct super_block *sb = inode->i_sb;
346 	struct nilfs_sb_info *sbi = NILFS_SB(sb);
347 
348 	clear_inode(inode);
349 	/* XXX: check error code? Is there any thing I can do? */
350 	(void) nilfs_ifile_delete_inode(sbi->s_ifile, inode->i_ino);
351 	atomic_dec(&sbi->s_inodes_count);
352 }
353 
354 void nilfs_set_inode_flags(struct inode *inode)
355 {
356 	unsigned int flags = NILFS_I(inode)->i_flags;
357 
358 	inode->i_flags &= ~(S_SYNC | S_APPEND | S_IMMUTABLE | S_NOATIME |
359 			    S_DIRSYNC);
360 	if (flags & NILFS_SYNC_FL)
361 		inode->i_flags |= S_SYNC;
362 	if (flags & NILFS_APPEND_FL)
363 		inode->i_flags |= S_APPEND;
364 	if (flags & NILFS_IMMUTABLE_FL)
365 		inode->i_flags |= S_IMMUTABLE;
366 #ifndef NILFS_ATIME_DISABLE
367 	if (flags & NILFS_NOATIME_FL)
368 #endif
369 		inode->i_flags |= S_NOATIME;
370 	if (flags & NILFS_DIRSYNC_FL)
371 		inode->i_flags |= S_DIRSYNC;
372 	mapping_set_gfp_mask(inode->i_mapping,
373 			     mapping_gfp_mask(inode->i_mapping) & ~__GFP_FS);
374 }
375 
376 int nilfs_read_inode_common(struct inode *inode,
377 			    struct nilfs_inode *raw_inode)
378 {
379 	struct nilfs_inode_info *ii = NILFS_I(inode);
380 	int err;
381 
382 	inode->i_mode = le16_to_cpu(raw_inode->i_mode);
383 	inode->i_uid = (uid_t)le32_to_cpu(raw_inode->i_uid);
384 	inode->i_gid = (gid_t)le32_to_cpu(raw_inode->i_gid);
385 	inode->i_nlink = le16_to_cpu(raw_inode->i_links_count);
386 	inode->i_size = le64_to_cpu(raw_inode->i_size);
387 	inode->i_atime.tv_sec = le64_to_cpu(raw_inode->i_mtime);
388 	inode->i_ctime.tv_sec = le64_to_cpu(raw_inode->i_ctime);
389 	inode->i_mtime.tv_sec = le64_to_cpu(raw_inode->i_mtime);
390 	inode->i_atime.tv_nsec = le32_to_cpu(raw_inode->i_mtime_nsec);
391 	inode->i_ctime.tv_nsec = le32_to_cpu(raw_inode->i_ctime_nsec);
392 	inode->i_mtime.tv_nsec = le32_to_cpu(raw_inode->i_mtime_nsec);
393 	if (inode->i_nlink == 0 && inode->i_mode == 0)
394 		return -EINVAL; /* this inode is deleted */
395 
396 	inode->i_blocks = le64_to_cpu(raw_inode->i_blocks);
397 	ii->i_flags = le32_to_cpu(raw_inode->i_flags);
398 #if 0
399 	ii->i_file_acl = le32_to_cpu(raw_inode->i_file_acl);
400 	ii->i_dir_acl = S_ISREG(inode->i_mode) ?
401 		0 : le32_to_cpu(raw_inode->i_dir_acl);
402 #endif
403 	ii->i_dir_start_lookup = 0;
404 	ii->i_cno = 0;
405 	inode->i_generation = le32_to_cpu(raw_inode->i_generation);
406 
407 	if (S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
408 	    S_ISLNK(inode->i_mode)) {
409 		err = nilfs_bmap_read(ii->i_bmap, raw_inode);
410 		if (err < 0)
411 			return err;
412 		set_bit(NILFS_I_BMAP, &ii->i_state);
413 		/* No lock is needed; iget() ensures it. */
414 	}
415 	return 0;
416 }
417 
418 static int __nilfs_read_inode(struct super_block *sb, unsigned long ino,
419 			      struct inode *inode)
420 {
421 	struct nilfs_sb_info *sbi = NILFS_SB(sb);
422 	struct inode *dat = nilfs_dat_inode(sbi->s_nilfs);
423 	struct buffer_head *bh;
424 	struct nilfs_inode *raw_inode;
425 	int err;
426 
427 	down_read(&NILFS_MDT(dat)->mi_sem);	/* XXX */
428 	err = nilfs_ifile_get_inode_block(sbi->s_ifile, ino, &bh);
429 	if (unlikely(err))
430 		goto bad_inode;
431 
432 	raw_inode = nilfs_ifile_map_inode(sbi->s_ifile, ino, bh);
433 
434 	err = nilfs_read_inode_common(inode, raw_inode);
435 	if (err)
436 		goto failed_unmap;
437 
438 	if (S_ISREG(inode->i_mode)) {
439 		inode->i_op = &nilfs_file_inode_operations;
440 		inode->i_fop = &nilfs_file_operations;
441 		inode->i_mapping->a_ops = &nilfs_aops;
442 	} else if (S_ISDIR(inode->i_mode)) {
443 		inode->i_op = &nilfs_dir_inode_operations;
444 		inode->i_fop = &nilfs_dir_operations;
445 		inode->i_mapping->a_ops = &nilfs_aops;
446 	} else if (S_ISLNK(inode->i_mode)) {
447 		inode->i_op = &nilfs_symlink_inode_operations;
448 		inode->i_mapping->a_ops = &nilfs_aops;
449 	} else {
450 		inode->i_op = &nilfs_special_inode_operations;
451 		init_special_inode(
452 			inode, inode->i_mode,
453 			new_decode_dev(le64_to_cpu(raw_inode->i_device_code)));
454 	}
455 	nilfs_ifile_unmap_inode(sbi->s_ifile, ino, bh);
456 	brelse(bh);
457 	up_read(&NILFS_MDT(dat)->mi_sem);	/* XXX */
458 	nilfs_set_inode_flags(inode);
459 	return 0;
460 
461  failed_unmap:
462 	nilfs_ifile_unmap_inode(sbi->s_ifile, ino, bh);
463 	brelse(bh);
464 
465  bad_inode:
466 	up_read(&NILFS_MDT(dat)->mi_sem);	/* XXX */
467 	return err;
468 }
469 
470 struct inode *nilfs_iget(struct super_block *sb, unsigned long ino)
471 {
472 	struct inode *inode;
473 	int err;
474 
475 	inode = iget_locked(sb, ino);
476 	if (unlikely(!inode))
477 		return ERR_PTR(-ENOMEM);
478 	if (!(inode->i_state & I_NEW))
479 		return inode;
480 
481 	err = __nilfs_read_inode(sb, ino, inode);
482 	if (unlikely(err)) {
483 		iget_failed(inode);
484 		return ERR_PTR(err);
485 	}
486 	unlock_new_inode(inode);
487 	return inode;
488 }
489 
490 void nilfs_write_inode_common(struct inode *inode,
491 			      struct nilfs_inode *raw_inode, int has_bmap)
492 {
493 	struct nilfs_inode_info *ii = NILFS_I(inode);
494 
495 	raw_inode->i_mode = cpu_to_le16(inode->i_mode);
496 	raw_inode->i_uid = cpu_to_le32(inode->i_uid);
497 	raw_inode->i_gid = cpu_to_le32(inode->i_gid);
498 	raw_inode->i_links_count = cpu_to_le16(inode->i_nlink);
499 	raw_inode->i_size = cpu_to_le64(inode->i_size);
500 	raw_inode->i_ctime = cpu_to_le64(inode->i_ctime.tv_sec);
501 	raw_inode->i_mtime = cpu_to_le64(inode->i_mtime.tv_sec);
502 	raw_inode->i_ctime_nsec = cpu_to_le32(inode->i_ctime.tv_nsec);
503 	raw_inode->i_mtime_nsec = cpu_to_le32(inode->i_mtime.tv_nsec);
504 	raw_inode->i_blocks = cpu_to_le64(inode->i_blocks);
505 
506 	raw_inode->i_flags = cpu_to_le32(ii->i_flags);
507 	raw_inode->i_generation = cpu_to_le32(inode->i_generation);
508 
509 	if (has_bmap)
510 		nilfs_bmap_write(ii->i_bmap, raw_inode);
511 	else if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode))
512 		raw_inode->i_device_code =
513 			cpu_to_le64(new_encode_dev(inode->i_rdev));
514 	/* When extending inode, nilfs->ns_inode_size should be checked
515 	   for substitutions of appended fields */
516 }
517 
518 void nilfs_update_inode(struct inode *inode, struct buffer_head *ibh)
519 {
520 	ino_t ino = inode->i_ino;
521 	struct nilfs_inode_info *ii = NILFS_I(inode);
522 	struct super_block *sb = inode->i_sb;
523 	struct nilfs_sb_info *sbi = NILFS_SB(sb);
524 	struct nilfs_inode *raw_inode;
525 
526 	raw_inode = nilfs_ifile_map_inode(sbi->s_ifile, ino, ibh);
527 
528 	if (test_and_clear_bit(NILFS_I_NEW, &ii->i_state))
529 		memset(raw_inode, 0, NILFS_MDT(sbi->s_ifile)->mi_entry_size);
530 	set_bit(NILFS_I_INODE_DIRTY, &ii->i_state);
531 
532 	nilfs_write_inode_common(inode, raw_inode, 0);
533 		/* XXX: call with has_bmap = 0 is a workaround to avoid
534 		   deadlock of bmap. This delays update of i_bmap to just
535 		   before writing */
536 	nilfs_ifile_unmap_inode(sbi->s_ifile, ino, ibh);
537 }
538 
539 #define NILFS_MAX_TRUNCATE_BLOCKS	16384  /* 64MB for 4KB block */
540 
541 static void nilfs_truncate_bmap(struct nilfs_inode_info *ii,
542 				unsigned long from)
543 {
544 	unsigned long b;
545 	int ret;
546 
547 	if (!test_bit(NILFS_I_BMAP, &ii->i_state))
548 		return;
549  repeat:
550 	ret = nilfs_bmap_last_key(ii->i_bmap, &b);
551 	if (ret == -ENOENT)
552 		return;
553 	else if (ret < 0)
554 		goto failed;
555 
556 	if (b < from)
557 		return;
558 
559 	b -= min_t(unsigned long, NILFS_MAX_TRUNCATE_BLOCKS, b - from);
560 	ret = nilfs_bmap_truncate(ii->i_bmap, b);
561 	nilfs_relax_pressure_in_lock(ii->vfs_inode.i_sb);
562 	if (!ret || (ret == -ENOMEM &&
563 		     nilfs_bmap_truncate(ii->i_bmap, b) == 0))
564 		goto repeat;
565 
566  failed:
567 	if (ret == -EINVAL)
568 		nilfs_error(ii->vfs_inode.i_sb, __func__,
569 			    "bmap is broken (ino=%lu)", ii->vfs_inode.i_ino);
570 	else
571 		nilfs_warning(ii->vfs_inode.i_sb, __func__,
572 			      "failed to truncate bmap (ino=%lu, err=%d)",
573 			      ii->vfs_inode.i_ino, ret);
574 }
575 
576 void nilfs_truncate(struct inode *inode)
577 {
578 	unsigned long blkoff;
579 	unsigned int blocksize;
580 	struct nilfs_transaction_info ti;
581 	struct super_block *sb = inode->i_sb;
582 	struct nilfs_inode_info *ii = NILFS_I(inode);
583 
584 	if (!test_bit(NILFS_I_BMAP, &ii->i_state))
585 		return;
586 	if (IS_APPEND(inode) || IS_IMMUTABLE(inode))
587 		return;
588 
589 	blocksize = sb->s_blocksize;
590 	blkoff = (inode->i_size + blocksize - 1) >> sb->s_blocksize_bits;
591 	nilfs_transaction_begin(sb, &ti, 0); /* never fails */
592 
593 	block_truncate_page(inode->i_mapping, inode->i_size, nilfs_get_block);
594 
595 	nilfs_truncate_bmap(ii, blkoff);
596 
597 	inode->i_mtime = inode->i_ctime = CURRENT_TIME;
598 	if (IS_SYNC(inode))
599 		nilfs_set_transaction_flag(NILFS_TI_SYNC);
600 
601 	nilfs_mark_inode_dirty(inode);
602 	nilfs_set_file_dirty(NILFS_SB(sb), inode, 0);
603 	nilfs_transaction_commit(sb);
604 	/* May construct a logical segment and may fail in sync mode.
605 	   But truncate has no return value. */
606 }
607 
608 void nilfs_delete_inode(struct inode *inode)
609 {
610 	struct nilfs_transaction_info ti;
611 	struct super_block *sb = inode->i_sb;
612 	struct nilfs_inode_info *ii = NILFS_I(inode);
613 
614 	if (unlikely(is_bad_inode(inode))) {
615 		if (inode->i_data.nrpages)
616 			truncate_inode_pages(&inode->i_data, 0);
617 		clear_inode(inode);
618 		return;
619 	}
620 	nilfs_transaction_begin(sb, &ti, 0); /* never fails */
621 
622 	if (inode->i_data.nrpages)
623 		truncate_inode_pages(&inode->i_data, 0);
624 
625 	nilfs_truncate_bmap(ii, 0);
626 	nilfs_mark_inode_dirty(inode);
627 	nilfs_free_inode(inode);
628 	/* nilfs_free_inode() marks inode buffer dirty */
629 	if (IS_SYNC(inode))
630 		nilfs_set_transaction_flag(NILFS_TI_SYNC);
631 	nilfs_transaction_commit(sb);
632 	/* May construct a logical segment and may fail in sync mode.
633 	   But delete_inode has no return value. */
634 }
635 
636 int nilfs_setattr(struct dentry *dentry, struct iattr *iattr)
637 {
638 	struct nilfs_transaction_info ti;
639 	struct inode *inode = dentry->d_inode;
640 	struct super_block *sb = inode->i_sb;
641 	int err;
642 
643 	err = inode_change_ok(inode, iattr);
644 	if (err)
645 		return err;
646 
647 	err = nilfs_transaction_begin(sb, &ti, 0);
648 	if (unlikely(err))
649 		return err;
650 	err = inode_setattr(inode, iattr);
651 	if (!err && (iattr->ia_valid & ATTR_MODE))
652 		err = nilfs_acl_chmod(inode);
653 	if (likely(!err))
654 		err = nilfs_transaction_commit(sb);
655 	else
656 		nilfs_transaction_abort(sb);
657 
658 	return err;
659 }
660 
661 int nilfs_load_inode_block(struct nilfs_sb_info *sbi, struct inode *inode,
662 			   struct buffer_head **pbh)
663 {
664 	struct nilfs_inode_info *ii = NILFS_I(inode);
665 	int err;
666 
667 	spin_lock(&sbi->s_inode_lock);
668 	if (ii->i_bh == NULL) {
669 		spin_unlock(&sbi->s_inode_lock);
670 		err = nilfs_ifile_get_inode_block(sbi->s_ifile, inode->i_ino,
671 						  pbh);
672 		if (unlikely(err))
673 			return err;
674 		spin_lock(&sbi->s_inode_lock);
675 		if (ii->i_bh == NULL)
676 			ii->i_bh = *pbh;
677 		else {
678 			brelse(*pbh);
679 			*pbh = ii->i_bh;
680 		}
681 	} else
682 		*pbh = ii->i_bh;
683 
684 	get_bh(*pbh);
685 	spin_unlock(&sbi->s_inode_lock);
686 	return 0;
687 }
688 
689 int nilfs_inode_dirty(struct inode *inode)
690 {
691 	struct nilfs_inode_info *ii = NILFS_I(inode);
692 	struct nilfs_sb_info *sbi = NILFS_SB(inode->i_sb);
693 	int ret = 0;
694 
695 	if (!list_empty(&ii->i_dirty)) {
696 		spin_lock(&sbi->s_inode_lock);
697 		ret = test_bit(NILFS_I_DIRTY, &ii->i_state) ||
698 			test_bit(NILFS_I_BUSY, &ii->i_state);
699 		spin_unlock(&sbi->s_inode_lock);
700 	}
701 	return ret;
702 }
703 
704 int nilfs_set_file_dirty(struct nilfs_sb_info *sbi, struct inode *inode,
705 			 unsigned nr_dirty)
706 {
707 	struct nilfs_inode_info *ii = NILFS_I(inode);
708 
709 	atomic_add(nr_dirty, &sbi->s_nilfs->ns_ndirtyblks);
710 
711 	if (test_and_set_bit(NILFS_I_DIRTY, &ii->i_state))
712 		return 0;
713 
714 	spin_lock(&sbi->s_inode_lock);
715 	if (!test_bit(NILFS_I_QUEUED, &ii->i_state) &&
716 	    !test_bit(NILFS_I_BUSY, &ii->i_state)) {
717 		/* Because this routine may race with nilfs_dispose_list(),
718 		   we have to check NILFS_I_QUEUED here, too. */
719 		if (list_empty(&ii->i_dirty) && igrab(inode) == NULL) {
720 			/* This will happen when somebody is freeing
721 			   this inode. */
722 			nilfs_warning(sbi->s_super, __func__,
723 				      "cannot get inode (ino=%lu)\n",
724 				      inode->i_ino);
725 			spin_unlock(&sbi->s_inode_lock);
726 			return -EINVAL; /* NILFS_I_DIRTY may remain for
727 					   freeing inode */
728 		}
729 		list_del(&ii->i_dirty);
730 		list_add_tail(&ii->i_dirty, &sbi->s_dirty_files);
731 		set_bit(NILFS_I_QUEUED, &ii->i_state);
732 	}
733 	spin_unlock(&sbi->s_inode_lock);
734 	return 0;
735 }
736 
737 int nilfs_mark_inode_dirty(struct inode *inode)
738 {
739 	struct nilfs_sb_info *sbi = NILFS_SB(inode->i_sb);
740 	struct buffer_head *ibh;
741 	int err;
742 
743 	err = nilfs_load_inode_block(sbi, inode, &ibh);
744 	if (unlikely(err)) {
745 		nilfs_warning(inode->i_sb, __func__,
746 			      "failed to reget inode block.\n");
747 		return err;
748 	}
749 	nilfs_update_inode(inode, ibh);
750 	nilfs_mdt_mark_buffer_dirty(ibh);
751 	nilfs_mdt_mark_dirty(sbi->s_ifile);
752 	brelse(ibh);
753 	return 0;
754 }
755 
756 /**
757  * nilfs_dirty_inode - reflect changes on given inode to an inode block.
758  * @inode: inode of the file to be registered.
759  *
760  * nilfs_dirty_inode() loads a inode block containing the specified
761  * @inode and copies data from a nilfs_inode to a corresponding inode
762  * entry in the inode block. This operation is excluded from the segment
763  * construction. This function can be called both as a single operation
764  * and as a part of indivisible file operations.
765  */
766 void nilfs_dirty_inode(struct inode *inode)
767 {
768 	struct nilfs_transaction_info ti;
769 
770 	if (is_bad_inode(inode)) {
771 		nilfs_warning(inode->i_sb, __func__,
772 			      "tried to mark bad_inode dirty. ignored.\n");
773 		dump_stack();
774 		return;
775 	}
776 	nilfs_transaction_begin(inode->i_sb, &ti, 0);
777 	nilfs_mark_inode_dirty(inode);
778 	nilfs_transaction_commit(inode->i_sb); /* never fails */
779 }
780