Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6
[pandora-kernel.git] / fs / nilfs2 / inode.c
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  * Bulk read for direct-io is not supported yet. (should be supported)
47  */
48 int nilfs_get_block(struct inode *inode, sector_t blkoff,
49                     struct buffer_head *bh_result, int create)
50 {
51         struct nilfs_inode_info *ii = NILFS_I(inode);
52         unsigned long blknum = 0;
53         int err = 0, ret;
54         struct inode *dat = nilfs_dat_inode(NILFS_I_NILFS(inode));
55
56         /* This exclusion control is a workaround; should be revised */
57         down_read(&NILFS_MDT(dat)->mi_sem);     /* XXX */
58         ret = nilfs_bmap_lookup(ii->i_bmap, (unsigned long)blkoff, &blknum);
59         up_read(&NILFS_MDT(dat)->mi_sem);       /* XXX */
60         if (ret == 0) { /* found */
61                 map_bh(bh_result, inode->i_sb, blknum);
62                 goto out;
63         }
64         /* data block was not found */
65         if (ret == -ENOENT && create) {
66                 struct nilfs_transaction_info ti;
67
68                 bh_result->b_blocknr = 0;
69                 err = nilfs_transaction_begin(inode->i_sb, &ti, 1);
70                 if (unlikely(err))
71                         goto out;
72                 err = nilfs_bmap_insert(ii->i_bmap, (unsigned long)blkoff,
73                                         (unsigned long)bh_result);
74                 if (unlikely(err != 0)) {
75                         if (err == -EEXIST) {
76                                 /*
77                                  * The get_block() function could be called
78                                  * from multiple callers for an inode.
79                                  * However, the page having this block must
80                                  * be locked in this case.
81                                  */
82                                 printk(KERN_WARNING
83                                        "nilfs_get_block: a race condition "
84                                        "while inserting a data block. "
85                                        "(inode number=%lu, file block "
86                                        "offset=%llu)\n",
87                                        inode->i_ino,
88                                        (unsigned long long)blkoff);
89                                 err = 0;
90                         } else if (err == -EINVAL) {
91                                 nilfs_error(inode->i_sb, __func__,
92                                             "broken bmap (inode=%lu)\n",
93                                             inode->i_ino);
94                                 err = -EIO;
95                         }
96                         nilfs_transaction_abort(inode->i_sb);
97                         goto out;
98                 }
99                 nilfs_transaction_commit(inode->i_sb); /* never fails */
100                 /* Error handling should be detailed */
101                 set_buffer_new(bh_result);
102                 map_bh(bh_result, inode->i_sb, 0); /* dbn must be changed
103                                                       to proper value */
104         } else if (ret == -ENOENT) {
105                 /* not found is not error (e.g. hole); must return without
106                    the mapped state flag. */
107                 ;
108         } else {
109                 err = ret;
110         }
111
112  out:
113         return err;
114 }
115
116 /**
117  * nilfs_readpage() - implement readpage() method of nilfs_aops {}
118  * address_space_operations.
119  * @file - file struct of the file to be read
120  * @page - the page to be read
121  */
122 static int nilfs_readpage(struct file *file, struct page *page)
123 {
124         return mpage_readpage(page, nilfs_get_block);
125 }
126
127 /**
128  * nilfs_readpages() - implement readpages() method of nilfs_aops {}
129  * address_space_operations.
130  * @file - file struct of the file to be read
131  * @mapping - address_space struct used for reading multiple pages
132  * @pages - the pages to be read
133  * @nr_pages - number of pages to be read
134  */
135 static int nilfs_readpages(struct file *file, struct address_space *mapping,
136                            struct list_head *pages, unsigned nr_pages)
137 {
138         return mpage_readpages(mapping, pages, nr_pages, nilfs_get_block);
139 }
140
141 static int nilfs_writepages(struct address_space *mapping,
142                             struct writeback_control *wbc)
143 {
144         struct inode *inode = mapping->host;
145         int err = 0;
146
147         if (wbc->sync_mode == WB_SYNC_ALL)
148                 err = nilfs_construct_dsync_segment(inode->i_sb, inode,
149                                                     wbc->range_start,
150                                                     wbc->range_end);
151         return err;
152 }
153
154 static int nilfs_writepage(struct page *page, struct writeback_control *wbc)
155 {
156         struct inode *inode = page->mapping->host;
157         int err;
158
159         redirty_page_for_writepage(wbc, page);
160         unlock_page(page);
161
162         if (wbc->sync_mode == WB_SYNC_ALL) {
163                 err = nilfs_construct_segment(inode->i_sb);
164                 if (unlikely(err))
165                         return err;
166         } else if (wbc->for_reclaim)
167                 nilfs_flush_segment(inode->i_sb, inode->i_ino);
168
169         return 0;
170 }
171
172 static int nilfs_set_page_dirty(struct page *page)
173 {
174         int ret = __set_page_dirty_buffers(page);
175
176         if (ret) {
177                 struct inode *inode = page->mapping->host;
178                 struct nilfs_sb_info *sbi = NILFS_SB(inode->i_sb);
179                 unsigned nr_dirty = 1 << (PAGE_SHIFT - inode->i_blkbits);
180
181                 nilfs_set_file_dirty(sbi, inode, nr_dirty);
182         }
183         return ret;
184 }
185
186 static int nilfs_write_begin(struct file *file, struct address_space *mapping,
187                              loff_t pos, unsigned len, unsigned flags,
188                              struct page **pagep, void **fsdata)
189
190 {
191         struct inode *inode = mapping->host;
192         int err = nilfs_transaction_begin(inode->i_sb, NULL, 1);
193
194         if (unlikely(err))
195                 return err;
196
197         *pagep = NULL;
198         err = block_write_begin(file, mapping, pos, len, flags, pagep,
199                                 fsdata, nilfs_get_block);
200         if (unlikely(err))
201                 nilfs_transaction_abort(inode->i_sb);
202         return err;
203 }
204
205 static int nilfs_write_end(struct file *file, struct address_space *mapping,
206                            loff_t pos, unsigned len, unsigned copied,
207                            struct page *page, void *fsdata)
208 {
209         struct inode *inode = mapping->host;
210         unsigned start = pos & (PAGE_CACHE_SIZE - 1);
211         unsigned nr_dirty;
212         int err;
213
214         nr_dirty = nilfs_page_count_clean_buffers(page, start,
215                                                   start + copied);
216         copied = generic_write_end(file, mapping, pos, len, copied, page,
217                                    fsdata);
218         nilfs_set_file_dirty(NILFS_SB(inode->i_sb), inode, nr_dirty);
219         err = nilfs_transaction_commit(inode->i_sb);
220         return err ? : copied;
221 }
222
223 static ssize_t
224 nilfs_direct_IO(int rw, struct kiocb *iocb, const struct iovec *iov,
225                 loff_t offset, unsigned long nr_segs)
226 {
227         struct file *file = iocb->ki_filp;
228         struct inode *inode = file->f_mapping->host;
229         ssize_t size;
230
231         if (rw == WRITE)
232                 return 0;
233
234         /* Needs synchronization with the cleaner */
235         size = blockdev_direct_IO(rw, iocb, inode, inode->i_sb->s_bdev, iov,
236                                   offset, nr_segs, nilfs_get_block, NULL);
237         return size;
238 }
239
240 struct address_space_operations nilfs_aops = {
241         .writepage              = nilfs_writepage,
242         .readpage               = nilfs_readpage,
243         /* .sync_page           = nilfs_sync_page, */
244         .writepages             = nilfs_writepages,
245         .set_page_dirty         = nilfs_set_page_dirty,
246         .readpages              = nilfs_readpages,
247         .write_begin            = nilfs_write_begin,
248         .write_end              = nilfs_write_end,
249         /* .releasepage         = nilfs_releasepage, */
250         .invalidatepage         = block_invalidatepage,
251         .direct_IO              = nilfs_direct_IO,
252 };
253
254 struct inode *nilfs_new_inode(struct inode *dir, int mode)
255 {
256         struct super_block *sb = dir->i_sb;
257         struct nilfs_sb_info *sbi = NILFS_SB(sb);
258         struct inode *inode;
259         struct nilfs_inode_info *ii;
260         int err = -ENOMEM;
261         ino_t ino;
262
263         inode = new_inode(sb);
264         if (unlikely(!inode))
265                 goto failed;
266
267         mapping_set_gfp_mask(inode->i_mapping,
268                              mapping_gfp_mask(inode->i_mapping) & ~__GFP_FS);
269
270         ii = NILFS_I(inode);
271         ii->i_state = 1 << NILFS_I_NEW;
272
273         err = nilfs_ifile_create_inode(sbi->s_ifile, &ino, &ii->i_bh);
274         if (unlikely(err))
275                 goto failed_ifile_create_inode;
276         /* reference count of i_bh inherits from nilfs_mdt_read_block() */
277
278         atomic_inc(&sbi->s_inodes_count);
279
280         inode->i_uid = current_fsuid();
281         if (dir->i_mode & S_ISGID) {
282                 inode->i_gid = dir->i_gid;
283                 if (S_ISDIR(mode))
284                         mode |= S_ISGID;
285         } else
286                 inode->i_gid = current_fsgid();
287
288         inode->i_mode = mode;
289         inode->i_ino = ino;
290         inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
291
292         if (S_ISREG(mode) || S_ISDIR(mode) || S_ISLNK(mode)) {
293                 err = nilfs_bmap_read(ii->i_bmap, NULL);
294                 if (err < 0)
295                         goto failed_bmap;
296
297                 set_bit(NILFS_I_BMAP, &ii->i_state);
298                 /* No lock is needed; iget() ensures it. */
299         }
300
301         ii->i_flags = NILFS_I(dir)->i_flags;
302         if (S_ISLNK(mode))
303                 ii->i_flags &= ~(NILFS_IMMUTABLE_FL | NILFS_APPEND_FL);
304         if (!S_ISDIR(mode))
305                 ii->i_flags &= ~NILFS_DIRSYNC_FL;
306
307         /* ii->i_file_acl = 0; */
308         /* ii->i_dir_acl = 0; */
309         ii->i_dir_start_lookup = 0;
310 #ifdef CONFIG_NILFS_FS_POSIX_ACL
311         ii->i_acl = NULL;
312         ii->i_default_acl = NULL;
313 #endif
314         ii->i_cno = 0;
315         nilfs_set_inode_flags(inode);
316         spin_lock(&sbi->s_next_gen_lock);
317         inode->i_generation = sbi->s_next_generation++;
318         spin_unlock(&sbi->s_next_gen_lock);
319         insert_inode_hash(inode);
320
321         err = nilfs_init_acl(inode, dir);
322         if (unlikely(err))
323                 goto failed_acl; /* never occur. When supporting
324                                     nilfs_init_acl(), proper cancellation of
325                                     above jobs should be considered */
326
327         mark_inode_dirty(inode);
328         return inode;
329
330  failed_acl:
331  failed_bmap:
332         inode->i_nlink = 0;
333         iput(inode);  /* raw_inode will be deleted through
334                          generic_delete_inode() */
335         goto failed;
336
337  failed_ifile_create_inode:
338         make_bad_inode(inode);
339         iput(inode);  /* if i_nlink == 1, generic_forget_inode() will be
340                          called */
341  failed:
342         return ERR_PTR(err);
343 }
344
345 void nilfs_free_inode(struct inode *inode)
346 {
347         struct super_block *sb = inode->i_sb;
348         struct nilfs_sb_info *sbi = NILFS_SB(sb);
349
350         clear_inode(inode);
351         /* XXX: check error code? Is there any thing I can do? */
352         (void) nilfs_ifile_delete_inode(sbi->s_ifile, inode->i_ino);
353         atomic_dec(&sbi->s_inodes_count);
354 }
355
356 void nilfs_set_inode_flags(struct inode *inode)
357 {
358         unsigned int flags = NILFS_I(inode)->i_flags;
359
360         inode->i_flags &= ~(S_SYNC | S_APPEND | S_IMMUTABLE | S_NOATIME |
361                             S_DIRSYNC);
362         if (flags & NILFS_SYNC_FL)
363                 inode->i_flags |= S_SYNC;
364         if (flags & NILFS_APPEND_FL)
365                 inode->i_flags |= S_APPEND;
366         if (flags & NILFS_IMMUTABLE_FL)
367                 inode->i_flags |= S_IMMUTABLE;
368 #ifndef NILFS_ATIME_DISABLE
369         if (flags & NILFS_NOATIME_FL)
370 #endif
371                 inode->i_flags |= S_NOATIME;
372         if (flags & NILFS_DIRSYNC_FL)
373                 inode->i_flags |= S_DIRSYNC;
374         mapping_set_gfp_mask(inode->i_mapping,
375                              mapping_gfp_mask(inode->i_mapping) & ~__GFP_FS);
376 }
377
378 int nilfs_read_inode_common(struct inode *inode,
379                             struct nilfs_inode *raw_inode)
380 {
381         struct nilfs_inode_info *ii = NILFS_I(inode);
382         int err;
383
384         inode->i_mode = le16_to_cpu(raw_inode->i_mode);
385         inode->i_uid = (uid_t)le32_to_cpu(raw_inode->i_uid);
386         inode->i_gid = (gid_t)le32_to_cpu(raw_inode->i_gid);
387         inode->i_nlink = le16_to_cpu(raw_inode->i_links_count);
388         inode->i_size = le64_to_cpu(raw_inode->i_size);
389         inode->i_atime.tv_sec = le64_to_cpu(raw_inode->i_mtime);
390         inode->i_ctime.tv_sec = le64_to_cpu(raw_inode->i_ctime);
391         inode->i_mtime.tv_sec = le64_to_cpu(raw_inode->i_mtime);
392         inode->i_atime.tv_nsec = le32_to_cpu(raw_inode->i_mtime_nsec);
393         inode->i_ctime.tv_nsec = le32_to_cpu(raw_inode->i_ctime_nsec);
394         inode->i_mtime.tv_nsec = le32_to_cpu(raw_inode->i_mtime_nsec);
395         if (inode->i_nlink == 0 && inode->i_mode == 0)
396                 return -EINVAL; /* this inode is deleted */
397
398         inode->i_blocks = le64_to_cpu(raw_inode->i_blocks);
399         ii->i_flags = le32_to_cpu(raw_inode->i_flags);
400 #if 0
401         ii->i_file_acl = le32_to_cpu(raw_inode->i_file_acl);
402         ii->i_dir_acl = S_ISREG(inode->i_mode) ?
403                 0 : le32_to_cpu(raw_inode->i_dir_acl);
404 #endif
405         ii->i_cno = 0;
406         inode->i_generation = le32_to_cpu(raw_inode->i_generation);
407
408         if (S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
409             S_ISLNK(inode->i_mode)) {
410                 err = nilfs_bmap_read(ii->i_bmap, raw_inode);
411                 if (err < 0)
412                         return err;
413                 set_bit(NILFS_I_BMAP, &ii->i_state);
414                 /* No lock is needed; iget() ensures it. */
415         }
416         return 0;
417 }
418
419 static int __nilfs_read_inode(struct super_block *sb, unsigned long ino,
420                               struct inode *inode)
421 {
422         struct nilfs_sb_info *sbi = NILFS_SB(sb);
423         struct inode *dat = nilfs_dat_inode(sbi->s_nilfs);
424         struct buffer_head *bh;
425         struct nilfs_inode *raw_inode;
426         int err;
427
428         down_read(&NILFS_MDT(dat)->mi_sem);     /* XXX */
429         err = nilfs_ifile_get_inode_block(sbi->s_ifile, ino, &bh);
430         if (unlikely(err))
431                 goto bad_inode;
432
433         raw_inode = nilfs_ifile_map_inode(sbi->s_ifile, ino, bh);
434
435 #ifdef CONFIG_NILFS_FS_POSIX_ACL
436         ii->i_acl = NILFS_ACL_NOT_CACHED;
437         ii->i_default_acl = NILFS_ACL_NOT_CACHED;
438 #endif
439         if (nilfs_read_inode_common(inode, raw_inode))
440                 goto failed_unmap;
441
442         if (S_ISREG(inode->i_mode)) {
443                 inode->i_op = &nilfs_file_inode_operations;
444                 inode->i_fop = &nilfs_file_operations;
445                 inode->i_mapping->a_ops = &nilfs_aops;
446         } else if (S_ISDIR(inode->i_mode)) {
447                 inode->i_op = &nilfs_dir_inode_operations;
448                 inode->i_fop = &nilfs_dir_operations;
449                 inode->i_mapping->a_ops = &nilfs_aops;
450         } else if (S_ISLNK(inode->i_mode)) {
451                 inode->i_op = &nilfs_symlink_inode_operations;
452                 inode->i_mapping->a_ops = &nilfs_aops;
453         } else {
454                 inode->i_op = &nilfs_special_inode_operations;
455                 init_special_inode(
456                         inode, inode->i_mode,
457                         new_decode_dev(le64_to_cpu(raw_inode->i_device_code)));
458         }
459         nilfs_ifile_unmap_inode(sbi->s_ifile, ino, bh);
460         brelse(bh);
461         up_read(&NILFS_MDT(dat)->mi_sem);       /* XXX */
462         nilfs_set_inode_flags(inode);
463         return 0;
464
465  failed_unmap:
466         nilfs_ifile_unmap_inode(sbi->s_ifile, ino, bh);
467         brelse(bh);
468
469  bad_inode:
470         up_read(&NILFS_MDT(dat)->mi_sem);       /* XXX */
471         return err;
472 }
473
474 struct inode *nilfs_iget(struct super_block *sb, unsigned long ino)
475 {
476         struct inode *inode;
477         int err;
478
479         inode = iget_locked(sb, ino);
480         if (unlikely(!inode))
481                 return ERR_PTR(-ENOMEM);
482         if (!(inode->i_state & I_NEW))
483                 return inode;
484
485         err = __nilfs_read_inode(sb, ino, inode);
486         if (unlikely(err)) {
487                 iget_failed(inode);
488                 return ERR_PTR(err);
489         }
490         unlock_new_inode(inode);
491         return inode;
492 }
493
494 void nilfs_write_inode_common(struct inode *inode,
495                               struct nilfs_inode *raw_inode, int has_bmap)
496 {
497         struct nilfs_inode_info *ii = NILFS_I(inode);
498
499         raw_inode->i_mode = cpu_to_le16(inode->i_mode);
500         raw_inode->i_uid = cpu_to_le32(inode->i_uid);
501         raw_inode->i_gid = cpu_to_le32(inode->i_gid);
502         raw_inode->i_links_count = cpu_to_le16(inode->i_nlink);
503         raw_inode->i_size = cpu_to_le64(inode->i_size);
504         raw_inode->i_ctime = cpu_to_le64(inode->i_ctime.tv_sec);
505         raw_inode->i_mtime = cpu_to_le64(inode->i_mtime.tv_sec);
506         raw_inode->i_ctime_nsec = cpu_to_le32(inode->i_ctime.tv_nsec);
507         raw_inode->i_mtime_nsec = cpu_to_le32(inode->i_mtime.tv_nsec);
508         raw_inode->i_blocks = cpu_to_le64(inode->i_blocks);
509
510         raw_inode->i_flags = cpu_to_le32(ii->i_flags);
511         raw_inode->i_generation = cpu_to_le32(inode->i_generation);
512
513         if (has_bmap)
514                 nilfs_bmap_write(ii->i_bmap, raw_inode);
515         else if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode))
516                 raw_inode->i_device_code =
517                         cpu_to_le64(new_encode_dev(inode->i_rdev));
518         /* When extending inode, nilfs->ns_inode_size should be checked
519            for substitutions of appended fields */
520 }
521
522 void nilfs_update_inode(struct inode *inode, struct buffer_head *ibh)
523 {
524         ino_t ino = inode->i_ino;
525         struct nilfs_inode_info *ii = NILFS_I(inode);
526         struct super_block *sb = inode->i_sb;
527         struct nilfs_sb_info *sbi = NILFS_SB(sb);
528         struct nilfs_inode *raw_inode;
529
530         raw_inode = nilfs_ifile_map_inode(sbi->s_ifile, ino, ibh);
531
532         /* The buffer is guarded with lock_buffer() by the caller */
533         if (test_and_clear_bit(NILFS_I_NEW, &ii->i_state))
534                 memset(raw_inode, 0, NILFS_MDT(sbi->s_ifile)->mi_entry_size);
535         set_bit(NILFS_I_INODE_DIRTY, &ii->i_state);
536
537         nilfs_write_inode_common(inode, raw_inode, 0);
538                 /* XXX: call with has_bmap = 0 is a workaround to avoid
539                    deadlock of bmap. This delays update of i_bmap to just
540                    before writing */
541         nilfs_ifile_unmap_inode(sbi->s_ifile, ino, ibh);
542 }
543
544 #define NILFS_MAX_TRUNCATE_BLOCKS       16384  /* 64MB for 4KB block */
545
546 static void nilfs_truncate_bmap(struct nilfs_inode_info *ii,
547                                 unsigned long from)
548 {
549         unsigned long b;
550         int ret;
551
552         if (!test_bit(NILFS_I_BMAP, &ii->i_state))
553                 return;
554  repeat:
555         ret = nilfs_bmap_last_key(ii->i_bmap, &b);
556         if (ret == -ENOENT)
557                 return;
558         else if (ret < 0)
559                 goto failed;
560
561         if (b < from)
562                 return;
563
564         b -= min_t(unsigned long, NILFS_MAX_TRUNCATE_BLOCKS, b - from);
565         ret = nilfs_bmap_truncate(ii->i_bmap, b);
566         nilfs_relax_pressure_in_lock(ii->vfs_inode.i_sb);
567         if (!ret || (ret == -ENOMEM &&
568                      nilfs_bmap_truncate(ii->i_bmap, b) == 0))
569                 goto repeat;
570
571  failed:
572         if (ret == -EINVAL)
573                 nilfs_error(ii->vfs_inode.i_sb, __func__,
574                             "bmap is broken (ino=%lu)", ii->vfs_inode.i_ino);
575         else
576                 nilfs_warning(ii->vfs_inode.i_sb, __func__,
577                               "failed to truncate bmap (ino=%lu, err=%d)",
578                               ii->vfs_inode.i_ino, ret);
579 }
580
581 void nilfs_truncate(struct inode *inode)
582 {
583         unsigned long blkoff;
584         unsigned int blocksize;
585         struct nilfs_transaction_info ti;
586         struct super_block *sb = inode->i_sb;
587         struct nilfs_inode_info *ii = NILFS_I(inode);
588
589         if (!test_bit(NILFS_I_BMAP, &ii->i_state))
590                 return;
591         if (IS_APPEND(inode) || IS_IMMUTABLE(inode))
592                 return;
593
594         blocksize = sb->s_blocksize;
595         blkoff = (inode->i_size + blocksize - 1) >> sb->s_blocksize_bits;
596         nilfs_transaction_begin(sb, &ti, 0); /* never fails */
597
598         block_truncate_page(inode->i_mapping, inode->i_size, nilfs_get_block);
599
600         nilfs_truncate_bmap(ii, blkoff);
601
602         inode->i_mtime = inode->i_ctime = CURRENT_TIME;
603         if (IS_SYNC(inode))
604                 nilfs_set_transaction_flag(NILFS_TI_SYNC);
605
606         nilfs_set_file_dirty(NILFS_SB(sb), inode, 0);
607         nilfs_transaction_commit(sb);
608         /* May construct a logical segment and may fail in sync mode.
609            But truncate has no return value. */
610 }
611
612 void nilfs_delete_inode(struct inode *inode)
613 {
614         struct nilfs_transaction_info ti;
615         struct super_block *sb = inode->i_sb;
616         struct nilfs_inode_info *ii = NILFS_I(inode);
617
618         if (unlikely(is_bad_inode(inode))) {
619                 if (inode->i_data.nrpages)
620                         truncate_inode_pages(&inode->i_data, 0);
621                 clear_inode(inode);
622                 return;
623         }
624         nilfs_transaction_begin(sb, &ti, 0); /* never fails */
625
626         if (inode->i_data.nrpages)
627                 truncate_inode_pages(&inode->i_data, 0);
628
629         nilfs_truncate_bmap(ii, 0);
630         nilfs_free_inode(inode);
631         /* nilfs_free_inode() marks inode buffer dirty */
632         if (IS_SYNC(inode))
633                 nilfs_set_transaction_flag(NILFS_TI_SYNC);
634         nilfs_transaction_commit(sb);
635         /* May construct a logical segment and may fail in sync mode.
636            But delete_inode has no return value. */
637 }
638
639 int nilfs_setattr(struct dentry *dentry, struct iattr *iattr)
640 {
641         struct nilfs_transaction_info ti;
642         struct inode *inode = dentry->d_inode;
643         struct super_block *sb = inode->i_sb;
644         int err;
645
646         err = inode_change_ok(inode, iattr);
647         if (err)
648                 return err;
649
650         err = nilfs_transaction_begin(sb, &ti, 0);
651         if (unlikely(err))
652                 return err;
653         err = inode_setattr(inode, iattr);
654         if (!err && (iattr->ia_valid & ATTR_MODE))
655                 err = nilfs_acl_chmod(inode);
656         if (likely(!err))
657                 err = nilfs_transaction_commit(sb);
658         else
659                 nilfs_transaction_abort(sb);
660
661         return err;
662 }
663
664 int nilfs_load_inode_block(struct nilfs_sb_info *sbi, struct inode *inode,
665                            struct buffer_head **pbh)
666 {
667         struct nilfs_inode_info *ii = NILFS_I(inode);
668         int err;
669
670         spin_lock(&sbi->s_inode_lock);
671         /* Caller of this function MUST lock s_inode_lock */
672         if (ii->i_bh == NULL) {
673                 spin_unlock(&sbi->s_inode_lock);
674                 err = nilfs_ifile_get_inode_block(sbi->s_ifile, inode->i_ino,
675                                                   pbh);
676                 if (unlikely(err))
677                         return err;
678                 spin_lock(&sbi->s_inode_lock);
679                 if (ii->i_bh == NULL)
680                         ii->i_bh = *pbh;
681                 else {
682                         brelse(*pbh);
683                         *pbh = ii->i_bh;
684                 }
685         } else
686                 *pbh = ii->i_bh;
687
688         get_bh(*pbh);
689         spin_unlock(&sbi->s_inode_lock);
690         return 0;
691 }
692
693 int nilfs_inode_dirty(struct inode *inode)
694 {
695         struct nilfs_inode_info *ii = NILFS_I(inode);
696         struct nilfs_sb_info *sbi = NILFS_SB(inode->i_sb);
697         int ret = 0;
698
699         if (!list_empty(&ii->i_dirty)) {
700                 spin_lock(&sbi->s_inode_lock);
701                 ret = test_bit(NILFS_I_DIRTY, &ii->i_state) ||
702                         test_bit(NILFS_I_BUSY, &ii->i_state);
703                 spin_unlock(&sbi->s_inode_lock);
704         }
705         return ret;
706 }
707
708 int nilfs_set_file_dirty(struct nilfs_sb_info *sbi, struct inode *inode,
709                          unsigned nr_dirty)
710 {
711         struct nilfs_inode_info *ii = NILFS_I(inode);
712
713         atomic_add(nr_dirty, &sbi->s_nilfs->ns_ndirtyblks);
714
715         if (test_and_set_bit(NILFS_I_DIRTY, &ii->i_state))
716                 return 0;
717
718         spin_lock(&sbi->s_inode_lock);
719         if (!test_bit(NILFS_I_QUEUED, &ii->i_state) &&
720             !test_bit(NILFS_I_BUSY, &ii->i_state)) {
721                 /* Because this routine may race with nilfs_dispose_list(),
722                    we have to check NILFS_I_QUEUED here, too. */
723                 if (list_empty(&ii->i_dirty) && igrab(inode) == NULL) {
724                         /* This will happen when somebody is freeing
725                            this inode. */
726                         nilfs_warning(sbi->s_super, __func__,
727                                       "cannot get inode (ino=%lu)\n",
728                                       inode->i_ino);
729                         spin_unlock(&sbi->s_inode_lock);
730                         return -EINVAL; /* NILFS_I_DIRTY may remain for
731                                            freeing inode */
732                 }
733                 list_del(&ii->i_dirty);
734                 list_add_tail(&ii->i_dirty, &sbi->s_dirty_files);
735                 set_bit(NILFS_I_QUEUED, &ii->i_state);
736         }
737         spin_unlock(&sbi->s_inode_lock);
738         return 0;
739 }
740
741 int nilfs_mark_inode_dirty(struct inode *inode)
742 {
743         struct nilfs_sb_info *sbi = NILFS_SB(inode->i_sb);
744         struct buffer_head *ibh;
745         int err;
746
747         err = nilfs_load_inode_block(sbi, inode, &ibh);
748         if (unlikely(err)) {
749                 nilfs_warning(inode->i_sb, __func__,
750                               "failed to reget inode block.\n");
751                 return err;
752         }
753         lock_buffer(ibh);
754         nilfs_update_inode(inode, ibh);
755         unlock_buffer(ibh);
756         nilfs_mdt_mark_buffer_dirty(ibh);
757         nilfs_mdt_mark_dirty(sbi->s_ifile);
758         brelse(ibh);
759         return 0;
760 }
761
762 /**
763  * nilfs_dirty_inode - reflect changes on given inode to an inode block.
764  * @inode: inode of the file to be registered.
765  *
766  * nilfs_dirty_inode() loads a inode block containing the specified
767  * @inode and copies data from a nilfs_inode to a corresponding inode
768  * entry in the inode block. This operation is excluded from the segment
769  * construction. This function can be called both as a single operation
770  * and as a part of indivisible file operations.
771  */
772 void nilfs_dirty_inode(struct inode *inode)
773 {
774         struct nilfs_transaction_info ti;
775
776         if (is_bad_inode(inode)) {
777                 nilfs_warning(inode->i_sb, __func__,
778                               "tried to mark bad_inode dirty. ignored.\n");
779                 dump_stack();
780                 return;
781         }
782         nilfs_transaction_begin(inode->i_sb, &ti, 0);
783         nilfs_mark_inode_dirty(inode);
784         nilfs_transaction_commit(inode->i_sb); /* never fails */
785 }