blob: de08c92f2e234c9db1b9773940d5db5ba263535f [file] [log] [blame]
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001/* * This file is part of UBIFS.
2 *
3 * Copyright (C) 2006-2008 Nokia Corporation.
4 * Copyright (C) 2006, 2007 University of Szeged, Hungary
5 *
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License version 2 as published by
8 * the Free Software Foundation.
9 *
10 * This program is distributed in the hope that it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
13 * more details.
14 *
15 * You should have received a copy of the GNU General Public License along with
16 * this program; if not, write to the Free Software Foundation, Inc., 51
17 * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
18 *
19 * Authors: Artem Bityutskiy (Битюцкий Артём)
20 * Adrian Hunter
21 * Zoltan Sogor
22 */
23
24/*
25 * This file implements directory operations.
26 *
27 * All FS operations in this file allocate budget before writing anything to the
28 * media. If they fail to allocate it, the error is returned. The only
29 * exceptions are 'ubifs_unlink()' and 'ubifs_rmdir()' which keep working even
30 * if they unable to allocate the budget, because deletion %-ENOSPC failure is
31 * not what users are usually ready to get. UBIFS budgeting subsystem has some
32 * space reserved for these purposes.
33 *
34 * All operations in this file write all inodes which they change straight
35 * away, instead of marking them dirty. For example, 'ubifs_link()' changes
36 * @i_size of the parent inode and writes the parent inode together with the
37 * target inode. This was done to simplify file-system recovery which would
38 * otherwise be very difficult to do. The only exception is rename which marks
39 * the re-named inode dirty (because its @i_ctime is updated) but does not
40 * write it, but just marks it as dirty.
41 */
42
43#include "ubifs.h"
44
45/**
46 * inherit_flags - inherit flags of the parent inode.
47 * @dir: parent inode
48 * @mode: new inode mode flags
49 *
50 * This is a helper function for 'ubifs_new_inode()' which inherits flag of the
51 * parent directory inode @dir. UBIFS inodes inherit the following flags:
52 * o %UBIFS_COMPR_FL, which is useful to switch compression on/of on
53 * sub-directory basis;
54 * o %UBIFS_SYNC_FL - useful for the same reasons;
55 * o %UBIFS_DIRSYNC_FL - similar, but relevant only to directories.
56 *
57 * This function returns the inherited flags.
58 */
Al Viroad44be52011-07-26 03:12:59 -040059static int inherit_flags(const struct inode *dir, umode_t mode)
Artem Bityutskiy1e517642008-07-14 19:08:37 +030060{
61 int flags;
62 const struct ubifs_inode *ui = ubifs_inode(dir);
63
64 if (!S_ISDIR(dir->i_mode))
65 /*
66 * The parent is not a directory, which means that an extended
67 * attribute inode is being created. No flags.
68 */
69 return 0;
70
71 flags = ui->flags & (UBIFS_COMPR_FL | UBIFS_SYNC_FL | UBIFS_DIRSYNC_FL);
72 if (!S_ISDIR(mode))
73 /* The "DIRSYNC" flag only applies to directories */
74 flags &= ~UBIFS_DIRSYNC_FL;
75 return flags;
76}
77
78/**
79 * ubifs_new_inode - allocate new UBIFS inode object.
80 * @c: UBIFS file-system description object
81 * @dir: parent directory inode
82 * @mode: inode mode flags
83 *
84 * This function finds an unused inode number, allocates new inode and
85 * initializes it. Returns new inode in case of success and an error code in
86 * case of failure.
87 */
88struct inode *ubifs_new_inode(struct ubifs_info *c, const struct inode *dir,
Al Viroad44be52011-07-26 03:12:59 -040089 umode_t mode)
Artem Bityutskiy1e517642008-07-14 19:08:37 +030090{
91 struct inode *inode;
92 struct ubifs_inode *ui;
93
94 inode = new_inode(c->vfs_sb);
95 ui = ubifs_inode(inode);
96 if (!inode)
97 return ERR_PTR(-ENOMEM);
98
99 /*
100 * Set 'S_NOCMTIME' to prevent VFS form updating [mc]time of inodes and
101 * marking them dirty in file write path (see 'file_update_time()').
102 * UBIFS has to fully control "clean <-> dirty" transitions of inodes
103 * to make budgeting work.
104 */
Artem Bityutskiy12e776a2011-05-27 15:50:39 +0300105 inode->i_flags |= S_NOCMTIME;
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300106
Dmitry Monakhovabf5d082010-03-04 17:32:21 +0300107 inode_init_owner(inode, dir, mode);
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300108 inode->i_mtime = inode->i_atime = inode->i_ctime =
109 ubifs_current_time(inode);
110 inode->i_mapping->nrpages = 0;
111 /* Disable readahead */
112 inode->i_mapping->backing_dev_info = &c->bdi;
113
114 switch (mode & S_IFMT) {
115 case S_IFREG:
116 inode->i_mapping->a_ops = &ubifs_file_address_operations;
117 inode->i_op = &ubifs_file_inode_operations;
118 inode->i_fop = &ubifs_file_operations;
119 break;
120 case S_IFDIR:
121 inode->i_op = &ubifs_dir_inode_operations;
122 inode->i_fop = &ubifs_dir_operations;
123 inode->i_size = ui->ui_size = UBIFS_INO_NODE_SZ;
124 break;
125 case S_IFLNK:
126 inode->i_op = &ubifs_symlink_inode_operations;
127 break;
128 case S_IFSOCK:
129 case S_IFIFO:
130 case S_IFBLK:
131 case S_IFCHR:
132 inode->i_op = &ubifs_file_inode_operations;
133 break;
134 default:
135 BUG();
136 }
137
138 ui->flags = inherit_flags(dir, mode);
139 ubifs_set_inode_flags(inode);
140 if (S_ISREG(mode))
141 ui->compr_type = c->default_compr;
142 else
143 ui->compr_type = UBIFS_COMPR_NONE;
144 ui->synced_i_size = 0;
145
146 spin_lock(&c->cnt_lock);
147 /* Inode number overflow is currently not supported */
148 if (c->highest_inum >= INUM_WARN_WATERMARK) {
149 if (c->highest_inum >= INUM_WATERMARK) {
150 spin_unlock(&c->cnt_lock);
151 ubifs_err("out of inode numbers");
152 make_bad_inode(inode);
153 iput(inode);
154 return ERR_PTR(-EINVAL);
155 }
156 ubifs_warn("running out of inode numbers (current %lu, max %d)",
Artem Bityutskiye84461a2008-10-29 12:08:43 +0200157 (unsigned long)c->highest_inum, INUM_WATERMARK);
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300158 }
159
160 inode->i_ino = ++c->highest_inum;
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300161 /*
162 * The creation sequence number remains with this inode for its
163 * lifetime. All nodes for this inode have a greater sequence number,
164 * and so it is possible to distinguish obsolete nodes belonging to a
165 * previous incarnation of the same inode number - for example, for the
166 * purpose of rebuilding the index.
167 */
168 ui->creat_sqnum = ++c->max_sqnum;
169 spin_unlock(&c->cnt_lock);
170 return inode;
171}
172
Artem Bityutskiybb2615d2011-05-31 17:47:53 +0300173static int dbg_check_name(const struct ubifs_info *c,
174 const struct ubifs_dent_node *dent,
175 const struct qstr *nm)
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300176{
Artem Bityutskiy2b1844a2011-06-03 08:31:29 +0300177 if (!dbg_is_chk_gen(c))
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300178 return 0;
179 if (le16_to_cpu(dent->nlen) != nm->len)
180 return -EINVAL;
181 if (memcmp(dent->name, nm->name, nm->len))
182 return -EINVAL;
183 return 0;
184}
185
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300186static struct dentry *ubifs_lookup(struct inode *dir, struct dentry *dentry,
Al Viro00cd8dd2012-06-10 17:13:09 -0400187 unsigned int flags)
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300188{
189 int err;
190 union ubifs_key key;
191 struct inode *inode = NULL;
192 struct ubifs_dent_node *dent;
193 struct ubifs_info *c = dir->i_sb->s_fs_info;
194
195 dbg_gen("'%.*s' in dir ino %lu",
196 dentry->d_name.len, dentry->d_name.name, dir->i_ino);
197
198 if (dentry->d_name.len > UBIFS_MAX_NLEN)
199 return ERR_PTR(-ENAMETOOLONG);
200
201 dent = kmalloc(UBIFS_MAX_DENT_NODE_SZ, GFP_NOFS);
202 if (!dent)
203 return ERR_PTR(-ENOMEM);
204
205 dent_key_init(c, &key, dir->i_ino, &dentry->d_name);
206
207 err = ubifs_tnc_lookup_nm(c, &key, dent, &dentry->d_name);
208 if (err) {
Artem Bityutskiy720b4992008-08-13 16:16:31 +0300209 if (err == -ENOENT) {
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300210 dbg_gen("not found");
211 goto done;
212 }
213 goto out;
214 }
215
Artem Bityutskiybb2615d2011-05-31 17:47:53 +0300216 if (dbg_check_name(c, dent, &dentry->d_name)) {
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300217 err = -EINVAL;
218 goto out;
219 }
220
221 inode = ubifs_iget(dir->i_sb, le64_to_cpu(dent->inum));
222 if (IS_ERR(inode)) {
223 /*
224 * This should not happen. Probably the file-system needs
225 * checking.
226 */
227 err = PTR_ERR(inode);
228 ubifs_err("dead directory entry '%.*s', error %d",
229 dentry->d_name.len, dentry->d_name.name, err);
230 ubifs_ro_mode(c, err);
231 goto out;
232 }
233
234done:
235 kfree(dent);
236 /*
237 * Note, d_splice_alias() would be required instead if we supported
238 * NFS.
239 */
240 d_add(dentry, inode);
241 return NULL;
242
243out:
244 kfree(dent);
245 return ERR_PTR(err);
246}
247
Al Viro4acdaf22011-07-26 01:42:34 -0400248static int ubifs_create(struct inode *dir, struct dentry *dentry, umode_t mode,
Al Viroebfc3b42012-06-10 18:05:36 -0400249 bool excl)
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300250{
251 struct inode *inode;
252 struct ubifs_info *c = dir->i_sb->s_fs_info;
253 int err, sz_change = CALC_DENT_SIZE(dentry->d_name.len);
254 struct ubifs_budget_req req = { .new_ino = 1, .new_dent = 1,
255 .dirtied_ino = 1 };
256 struct ubifs_inode *dir_ui = ubifs_inode(dir);
257
258 /*
259 * Budget request settings: new inode, new direntry, changing the
260 * parent directory inode.
261 */
262
Al Viro4acdaf22011-07-26 01:42:34 -0400263 dbg_gen("dent '%.*s', mode %#hx in dir ino %lu",
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300264 dentry->d_name.len, dentry->d_name.name, mode, dir->i_ino);
265
266 err = ubifs_budget_space(c, &req);
267 if (err)
268 return err;
269
270 inode = ubifs_new_inode(c, dir, mode);
271 if (IS_ERR(inode)) {
272 err = PTR_ERR(inode);
273 goto out_budg;
274 }
275
276 mutex_lock(&dir_ui->ui_mutex);
277 dir->i_size += sz_change;
278 dir_ui->ui_size = dir->i_size;
279 dir->i_mtime = dir->i_ctime = inode->i_ctime;
280 err = ubifs_jnl_update(c, dir, &dentry->d_name, inode, 0, 0);
281 if (err)
282 goto out_cancel;
283 mutex_unlock(&dir_ui->ui_mutex);
284
285 ubifs_release_budget(c, &req);
286 insert_inode_hash(inode);
287 d_instantiate(dentry, inode);
288 return 0;
289
290out_cancel:
291 dir->i_size -= sz_change;
292 dir_ui->ui_size = dir->i_size;
293 mutex_unlock(&dir_ui->ui_mutex);
294 make_bad_inode(inode);
295 iput(inode);
296out_budg:
297 ubifs_release_budget(c, &req);
298 ubifs_err("cannot create regular file, error %d", err);
299 return err;
300}
301
302/**
303 * vfs_dent_type - get VFS directory entry type.
304 * @type: UBIFS directory entry type
305 *
306 * This function converts UBIFS directory entry type into VFS directory entry
307 * type.
308 */
309static unsigned int vfs_dent_type(uint8_t type)
310{
311 switch (type) {
312 case UBIFS_ITYPE_REG:
313 return DT_REG;
314 case UBIFS_ITYPE_DIR:
315 return DT_DIR;
316 case UBIFS_ITYPE_LNK:
317 return DT_LNK;
318 case UBIFS_ITYPE_BLK:
319 return DT_BLK;
320 case UBIFS_ITYPE_CHR:
321 return DT_CHR;
322 case UBIFS_ITYPE_FIFO:
323 return DT_FIFO;
324 case UBIFS_ITYPE_SOCK:
325 return DT_SOCK;
326 default:
327 BUG();
328 }
329 return 0;
330}
331
332/*
333 * The classical Unix view for directory is that it is a linear array of
334 * (name, inode number) entries. Linux/VFS assumes this model as well.
335 * Particularly, 'readdir()' call wants us to return a directory entry offset
336 * which later may be used to continue 'readdir()'ing the directory or to
337 * 'seek()' to that specific direntry. Obviously UBIFS does not really fit this
338 * model because directory entries are identified by keys, which may collide.
339 *
340 * UBIFS uses directory entry hash value for directory offsets, so
341 * 'seekdir()'/'telldir()' may not always work because of possible key
342 * collisions. But UBIFS guarantees that consecutive 'readdir()' calls work
343 * properly by means of saving full directory entry name in the private field
344 * of the file description object.
345 *
346 * This means that UBIFS cannot support NFS which requires full
347 * 'seekdir()'/'telldir()' support.
348 */
349static int ubifs_readdir(struct file *file, void *dirent, filldir_t filldir)
350{
351 int err, over = 0;
352 struct qstr nm;
353 union ubifs_key key;
354 struct ubifs_dent_node *dent;
Al Viro496ad9a2013-01-23 17:07:38 -0500355 struct inode *dir = file_inode(file);
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300356 struct ubifs_info *c = dir->i_sb->s_fs_info;
357
358 dbg_gen("dir ino %lu, f_pos %#llx", dir->i_ino, file->f_pos);
359
360 if (file->f_pos > UBIFS_S_KEY_HASH_MASK || file->f_pos == 2)
361 /*
362 * The directory was seek'ed to a senseless position or there
363 * are no more entries.
364 */
365 return 0;
366
367 /* File positions 0 and 1 correspond to "." and ".." */
368 if (file->f_pos == 0) {
369 ubifs_assert(!file->private_data);
370 over = filldir(dirent, ".", 1, 0, dir->i_ino, DT_DIR);
371 if (over)
372 return 0;
373 file->f_pos = 1;
374 }
375
376 if (file->f_pos == 1) {
377 ubifs_assert(!file->private_data);
378 over = filldir(dirent, "..", 2, 1,
379 parent_ino(file->f_path.dentry), DT_DIR);
380 if (over)
381 return 0;
382
383 /* Find the first entry in TNC and save it */
384 lowest_dent_key(c, &key, dir->i_ino);
385 nm.name = NULL;
386 dent = ubifs_tnc_next_ent(c, &key, &nm);
387 if (IS_ERR(dent)) {
388 err = PTR_ERR(dent);
389 goto out;
390 }
391
392 file->f_pos = key_hash_flash(c, &dent->key);
393 file->private_data = dent;
394 }
395
396 dent = file->private_data;
397 if (!dent) {
398 /*
399 * The directory was seek'ed to and is now readdir'ed.
400 * Find the entry corresponding to @file->f_pos or the
401 * closest one.
402 */
403 dent_key_init_hash(c, &key, dir->i_ino, file->f_pos);
404 nm.name = NULL;
405 dent = ubifs_tnc_next_ent(c, &key, &nm);
406 if (IS_ERR(dent)) {
407 err = PTR_ERR(dent);
408 goto out;
409 }
410 file->f_pos = key_hash_flash(c, &dent->key);
411 file->private_data = dent;
412 }
413
414 while (1) {
415 dbg_gen("feed '%s', ino %llu, new f_pos %#x",
Alexander Beregalov7424bac2008-09-17 22:09:41 +0400416 dent->name, (unsigned long long)le64_to_cpu(dent->inum),
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300417 key_hash_flash(c, &dent->key));
Harvey Harrison0ecb9522008-10-24 10:52:57 -0700418 ubifs_assert(le64_to_cpu(dent->ch.sqnum) >
419 ubifs_inode(dir)->creat_sqnum);
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300420
421 nm.len = le16_to_cpu(dent->nlen);
422 over = filldir(dirent, dent->name, nm.len, file->f_pos,
423 le64_to_cpu(dent->inum),
424 vfs_dent_type(dent->type));
425 if (over)
426 return 0;
427
428 /* Switch to the next entry */
429 key_read(c, &dent->key, &key);
430 nm.name = dent->name;
431 dent = ubifs_tnc_next_ent(c, &key, &nm);
432 if (IS_ERR(dent)) {
433 err = PTR_ERR(dent);
434 goto out;
435 }
436
437 kfree(file->private_data);
438 file->f_pos = key_hash_flash(c, &dent->key);
439 file->private_data = dent;
440 cond_resched();
441 }
442
443out:
444 if (err != -ENOENT) {
445 ubifs_err("cannot find next direntry, error %d", err);
446 return err;
447 }
448
449 kfree(file->private_data);
450 file->private_data = NULL;
451 file->f_pos = 2;
452 return 0;
453}
454
455/* If a directory is seeked, we have to free saved readdir() state */
Andrew Morton965c8e52012-12-17 15:59:39 -0800456static loff_t ubifs_dir_llseek(struct file *file, loff_t offset, int whence)
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300457{
458 kfree(file->private_data);
459 file->private_data = NULL;
Andrew Morton965c8e52012-12-17 15:59:39 -0800460 return generic_file_llseek(file, offset, whence);
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300461}
462
463/* Free saved readdir() state when the directory is closed */
464static int ubifs_dir_release(struct inode *dir, struct file *file)
465{
466 kfree(file->private_data);
467 file->private_data = NULL;
468 return 0;
469}
470
471/**
Artem Bityutskiy82c15932009-01-20 16:46:02 +0200472 * lock_2_inodes - a wrapper for locking two UBIFS inodes.
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300473 * @inode1: first inode
474 * @inode2: second inode
Artem Bityutskiy82c15932009-01-20 16:46:02 +0200475 *
476 * We do not implement any tricks to guarantee strict lock ordering, because
477 * VFS has already done it for us on the @i_mutex. So this is just a simple
478 * wrapper function.
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300479 */
480static void lock_2_inodes(struct inode *inode1, struct inode *inode2)
481{
Artem Bityutskiy82c15932009-01-20 16:46:02 +0200482 mutex_lock_nested(&ubifs_inode(inode1)->ui_mutex, WB_MUTEX_1);
483 mutex_lock_nested(&ubifs_inode(inode2)->ui_mutex, WB_MUTEX_2);
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300484}
485
486/**
Artem Bityutskiy82c15932009-01-20 16:46:02 +0200487 * unlock_2_inodes - a wrapper for unlocking two UBIFS inodes.
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300488 * @inode1: first inode
489 * @inode2: second inode
490 */
491static void unlock_2_inodes(struct inode *inode1, struct inode *inode2)
492{
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300493 mutex_unlock(&ubifs_inode(inode2)->ui_mutex);
Artem Bityutskiy82c15932009-01-20 16:46:02 +0200494 mutex_unlock(&ubifs_inode(inode1)->ui_mutex);
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300495}
496
497static int ubifs_link(struct dentry *old_dentry, struct inode *dir,
498 struct dentry *dentry)
499{
500 struct ubifs_info *c = dir->i_sb->s_fs_info;
501 struct inode *inode = old_dentry->d_inode;
502 struct ubifs_inode *ui = ubifs_inode(inode);
503 struct ubifs_inode *dir_ui = ubifs_inode(dir);
504 int err, sz_change = CALC_DENT_SIZE(dentry->d_name.len);
505 struct ubifs_budget_req req = { .new_dent = 1, .dirtied_ino = 2,
Artem Bityutskiydab4b4d2008-07-24 14:52:45 +0300506 .dirtied_ino_d = ALIGN(ui->data_len, 8) };
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300507
508 /*
509 * Budget request settings: new direntry, changing the target inode,
510 * changing the parent inode.
511 */
512
513 dbg_gen("dent '%.*s' to ino %lu (nlink %d) in dir ino %lu",
514 dentry->d_name.len, dentry->d_name.name, inode->i_ino,
515 inode->i_nlink, dir->i_ino);
Artem Bityutskiy82c15932009-01-20 16:46:02 +0200516 ubifs_assert(mutex_is_locked(&dir->i_mutex));
517 ubifs_assert(mutex_is_locked(&inode->i_mutex));
Hunter Adrian8b3884a2009-05-14 06:32:30 +0200518
Artem Bityutskiyd808efb2011-05-31 18:14:38 +0300519 err = dbg_check_synced_i_size(c, inode);
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300520 if (err)
521 return err;
522
523 err = ubifs_budget_space(c, &req);
524 if (err)
525 return err;
526
527 lock_2_inodes(dir, inode);
528 inc_nlink(inode);
Al Viro7de9c6ee2010-10-23 11:11:40 -0400529 ihold(inode);
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300530 inode->i_ctime = ubifs_current_time(inode);
531 dir->i_size += sz_change;
532 dir_ui->ui_size = dir->i_size;
533 dir->i_mtime = dir->i_ctime = inode->i_ctime;
534 err = ubifs_jnl_update(c, dir, &dentry->d_name, inode, 0, 0);
535 if (err)
536 goto out_cancel;
537 unlock_2_inodes(dir, inode);
538
539 ubifs_release_budget(c, &req);
540 d_instantiate(dentry, inode);
541 return 0;
542
543out_cancel:
544 dir->i_size -= sz_change;
545 dir_ui->ui_size = dir->i_size;
546 drop_nlink(inode);
547 unlock_2_inodes(dir, inode);
548 ubifs_release_budget(c, &req);
549 iput(inode);
550 return err;
551}
552
553static int ubifs_unlink(struct inode *dir, struct dentry *dentry)
554{
555 struct ubifs_info *c = dir->i_sb->s_fs_info;
556 struct inode *inode = dentry->d_inode;
557 struct ubifs_inode *dir_ui = ubifs_inode(dir);
558 int sz_change = CALC_DENT_SIZE(dentry->d_name.len);
559 int err, budgeted = 1;
560 struct ubifs_budget_req req = { .mod_dent = 1, .dirtied_ino = 2 };
Artem Bityutskiyc43be102012-02-07 10:58:51 +0200561 unsigned int saved_nlink = inode->i_nlink;
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300562
563 /*
564 * Budget request settings: deletion direntry, deletion inode (+1 for
565 * @dirtied_ino), changing the parent directory inode. If budgeting
566 * fails, go ahead anyway because we have extra space reserved for
567 * deletions.
568 */
569
570 dbg_gen("dent '%.*s' from ino %lu (nlink %d) in dir ino %lu",
571 dentry->d_name.len, dentry->d_name.name, inode->i_ino,
572 inode->i_nlink, dir->i_ino);
Artem Bityutskiy82c15932009-01-20 16:46:02 +0200573 ubifs_assert(mutex_is_locked(&dir->i_mutex));
574 ubifs_assert(mutex_is_locked(&inode->i_mutex));
Artem Bityutskiyd808efb2011-05-31 18:14:38 +0300575 err = dbg_check_synced_i_size(c, inode);
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300576 if (err)
577 return err;
578
579 err = ubifs_budget_space(c, &req);
580 if (err) {
581 if (err != -ENOSPC)
582 return err;
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300583 budgeted = 0;
584 }
585
586 lock_2_inodes(dir, inode);
587 inode->i_ctime = ubifs_current_time(dir);
588 drop_nlink(inode);
589 dir->i_size -= sz_change;
590 dir_ui->ui_size = dir->i_size;
591 dir->i_mtime = dir->i_ctime = inode->i_ctime;
592 err = ubifs_jnl_update(c, dir, &dentry->d_name, inode, 1, 0);
593 if (err)
594 goto out_cancel;
595 unlock_2_inodes(dir, inode);
596
597 if (budgeted)
598 ubifs_release_budget(c, &req);
599 else {
600 /* We've deleted something - clean the "no space" flags */
Artem Bityutskiyb1375452011-03-29 18:04:05 +0300601 c->bi.nospace = c->bi.nospace_rp = 0;
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300602 smp_wmb();
603 }
604 return 0;
605
606out_cancel:
607 dir->i_size += sz_change;
608 dir_ui->ui_size = dir->i_size;
Artem Bityutskiyc43be102012-02-07 10:58:51 +0200609 set_nlink(inode, saved_nlink);
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300610 unlock_2_inodes(dir, inode);
611 if (budgeted)
612 ubifs_release_budget(c, &req);
613 return err;
614}
615
616/**
617 * check_dir_empty - check if a directory is empty or not.
618 * @c: UBIFS file-system description object
619 * @dir: VFS inode object of the directory to check
620 *
621 * This function checks if directory @dir is empty. Returns zero if the
622 * directory is empty, %-ENOTEMPTY if it is not, and other negative error codes
623 * in case of of errors.
624 */
625static int check_dir_empty(struct ubifs_info *c, struct inode *dir)
626{
627 struct qstr nm = { .name = NULL };
628 struct ubifs_dent_node *dent;
629 union ubifs_key key;
630 int err;
631
632 lowest_dent_key(c, &key, dir->i_ino);
633 dent = ubifs_tnc_next_ent(c, &key, &nm);
634 if (IS_ERR(dent)) {
635 err = PTR_ERR(dent);
636 if (err == -ENOENT)
637 err = 0;
638 } else {
639 kfree(dent);
640 err = -ENOTEMPTY;
641 }
642 return err;
643}
644
645static int ubifs_rmdir(struct inode *dir, struct dentry *dentry)
646{
647 struct ubifs_info *c = dir->i_sb->s_fs_info;
648 struct inode *inode = dentry->d_inode;
649 int sz_change = CALC_DENT_SIZE(dentry->d_name.len);
650 int err, budgeted = 1;
651 struct ubifs_inode *dir_ui = ubifs_inode(dir);
652 struct ubifs_budget_req req = { .mod_dent = 1, .dirtied_ino = 2 };
653
654 /*
655 * Budget request settings: deletion direntry, deletion inode and
656 * changing the parent inode. If budgeting fails, go ahead anyway
657 * because we have extra space reserved for deletions.
658 */
659
660 dbg_gen("directory '%.*s', ino %lu in dir ino %lu", dentry->d_name.len,
661 dentry->d_name.name, inode->i_ino, dir->i_ino);
Artem Bityutskiy82c15932009-01-20 16:46:02 +0200662 ubifs_assert(mutex_is_locked(&dir->i_mutex));
663 ubifs_assert(mutex_is_locked(&inode->i_mutex));
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300664 err = check_dir_empty(c, dentry->d_inode);
665 if (err)
666 return err;
667
668 err = ubifs_budget_space(c, &req);
669 if (err) {
670 if (err != -ENOSPC)
671 return err;
672 budgeted = 0;
673 }
674
675 lock_2_inodes(dir, inode);
676 inode->i_ctime = ubifs_current_time(dir);
677 clear_nlink(inode);
678 drop_nlink(dir);
679 dir->i_size -= sz_change;
680 dir_ui->ui_size = dir->i_size;
681 dir->i_mtime = dir->i_ctime = inode->i_ctime;
682 err = ubifs_jnl_update(c, dir, &dentry->d_name, inode, 1, 0);
683 if (err)
684 goto out_cancel;
685 unlock_2_inodes(dir, inode);
686
687 if (budgeted)
688 ubifs_release_budget(c, &req);
689 else {
690 /* We've deleted something - clean the "no space" flags */
Artem Bityutskiyb1375452011-03-29 18:04:05 +0300691 c->bi.nospace = c->bi.nospace_rp = 0;
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300692 smp_wmb();
693 }
694 return 0;
695
696out_cancel:
697 dir->i_size += sz_change;
698 dir_ui->ui_size = dir->i_size;
699 inc_nlink(dir);
Artem Bityutskiyc43be102012-02-07 10:58:51 +0200700 set_nlink(inode, 2);
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300701 unlock_2_inodes(dir, inode);
702 if (budgeted)
703 ubifs_release_budget(c, &req);
704 return err;
705}
706
Al Viro18bb1db2011-07-26 01:41:39 -0400707static int ubifs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300708{
709 struct inode *inode;
710 struct ubifs_inode *dir_ui = ubifs_inode(dir);
711 struct ubifs_info *c = dir->i_sb->s_fs_info;
712 int err, sz_change = CALC_DENT_SIZE(dentry->d_name.len);
Artem Bityutskiy182854b2008-07-18 18:54:29 +0300713 struct ubifs_budget_req req = { .new_ino = 1, .new_dent = 1 };
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300714
715 /*
716 * Budget request settings: new inode, new direntry and changing parent
717 * directory inode.
718 */
719
Al Viro18bb1db2011-07-26 01:41:39 -0400720 dbg_gen("dent '%.*s', mode %#hx in dir ino %lu",
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300721 dentry->d_name.len, dentry->d_name.name, mode, dir->i_ino);
722
723 err = ubifs_budget_space(c, &req);
724 if (err)
725 return err;
726
727 inode = ubifs_new_inode(c, dir, S_IFDIR | mode);
728 if (IS_ERR(inode)) {
729 err = PTR_ERR(inode);
730 goto out_budg;
731 }
732
733 mutex_lock(&dir_ui->ui_mutex);
734 insert_inode_hash(inode);
735 inc_nlink(inode);
736 inc_nlink(dir);
737 dir->i_size += sz_change;
738 dir_ui->ui_size = dir->i_size;
739 dir->i_mtime = dir->i_ctime = inode->i_ctime;
740 err = ubifs_jnl_update(c, dir, &dentry->d_name, inode, 0, 0);
741 if (err) {
742 ubifs_err("cannot create directory, error %d", err);
743 goto out_cancel;
744 }
745 mutex_unlock(&dir_ui->ui_mutex);
746
747 ubifs_release_budget(c, &req);
748 d_instantiate(dentry, inode);
749 return 0;
750
751out_cancel:
752 dir->i_size -= sz_change;
753 dir_ui->ui_size = dir->i_size;
754 drop_nlink(dir);
755 mutex_unlock(&dir_ui->ui_mutex);
756 make_bad_inode(inode);
757 iput(inode);
758out_budg:
759 ubifs_release_budget(c, &req);
760 return err;
761}
762
763static int ubifs_mknod(struct inode *dir, struct dentry *dentry,
Al Viro1a67aaf2011-07-26 01:52:52 -0400764 umode_t mode, dev_t rdev)
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300765{
766 struct inode *inode;
767 struct ubifs_inode *ui;
768 struct ubifs_inode *dir_ui = ubifs_inode(dir);
769 struct ubifs_info *c = dir->i_sb->s_fs_info;
770 union ubifs_dev_desc *dev = NULL;
771 int sz_change = CALC_DENT_SIZE(dentry->d_name.len);
772 int err, devlen = 0;
773 struct ubifs_budget_req req = { .new_ino = 1, .new_dent = 1,
Artem Bityutskiydab4b4d2008-07-24 14:52:45 +0300774 .new_ino_d = ALIGN(devlen, 8),
775 .dirtied_ino = 1 };
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300776
777 /*
778 * Budget request settings: new inode, new direntry and changing parent
779 * directory inode.
780 */
781
782 dbg_gen("dent '%.*s' in dir ino %lu",
783 dentry->d_name.len, dentry->d_name.name, dir->i_ino);
784
785 if (!new_valid_dev(rdev))
786 return -EINVAL;
787
788 if (S_ISBLK(mode) || S_ISCHR(mode)) {
789 dev = kmalloc(sizeof(union ubifs_dev_desc), GFP_NOFS);
790 if (!dev)
791 return -ENOMEM;
792 devlen = ubifs_encode_dev(dev, rdev);
793 }
794
795 err = ubifs_budget_space(c, &req);
796 if (err) {
797 kfree(dev);
798 return err;
799 }
800
801 inode = ubifs_new_inode(c, dir, mode);
802 if (IS_ERR(inode)) {
803 kfree(dev);
804 err = PTR_ERR(inode);
805 goto out_budg;
806 }
807
808 init_special_inode(inode, inode->i_mode, rdev);
809 inode->i_size = ubifs_inode(inode)->ui_size = devlen;
810 ui = ubifs_inode(inode);
811 ui->data = dev;
812 ui->data_len = devlen;
813
814 mutex_lock(&dir_ui->ui_mutex);
815 dir->i_size += sz_change;
816 dir_ui->ui_size = dir->i_size;
817 dir->i_mtime = dir->i_ctime = inode->i_ctime;
818 err = ubifs_jnl_update(c, dir, &dentry->d_name, inode, 0, 0);
819 if (err)
820 goto out_cancel;
821 mutex_unlock(&dir_ui->ui_mutex);
822
823 ubifs_release_budget(c, &req);
824 insert_inode_hash(inode);
825 d_instantiate(dentry, inode);
826 return 0;
827
828out_cancel:
829 dir->i_size -= sz_change;
830 dir_ui->ui_size = dir->i_size;
831 mutex_unlock(&dir_ui->ui_mutex);
832 make_bad_inode(inode);
833 iput(inode);
834out_budg:
835 ubifs_release_budget(c, &req);
836 return err;
837}
838
839static int ubifs_symlink(struct inode *dir, struct dentry *dentry,
840 const char *symname)
841{
842 struct inode *inode;
843 struct ubifs_inode *ui;
844 struct ubifs_inode *dir_ui = ubifs_inode(dir);
845 struct ubifs_info *c = dir->i_sb->s_fs_info;
846 int err, len = strlen(symname);
847 int sz_change = CALC_DENT_SIZE(dentry->d_name.len);
848 struct ubifs_budget_req req = { .new_ino = 1, .new_dent = 1,
Artem Bityutskiydab4b4d2008-07-24 14:52:45 +0300849 .new_ino_d = ALIGN(len, 8),
850 .dirtied_ino = 1 };
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300851
852 /*
853 * Budget request settings: new inode, new direntry and changing parent
854 * directory inode.
855 */
856
857 dbg_gen("dent '%.*s', target '%s' in dir ino %lu", dentry->d_name.len,
858 dentry->d_name.name, symname, dir->i_ino);
859
860 if (len > UBIFS_MAX_INO_DATA)
861 return -ENAMETOOLONG;
862
863 err = ubifs_budget_space(c, &req);
864 if (err)
865 return err;
866
867 inode = ubifs_new_inode(c, dir, S_IFLNK | S_IRWXUGO);
868 if (IS_ERR(inode)) {
869 err = PTR_ERR(inode);
870 goto out_budg;
871 }
872
873 ui = ubifs_inode(inode);
874 ui->data = kmalloc(len + 1, GFP_NOFS);
875 if (!ui->data) {
876 err = -ENOMEM;
877 goto out_inode;
878 }
879
880 memcpy(ui->data, symname, len);
881 ((char *)ui->data)[len] = '\0';
882 /*
883 * The terminating zero byte is not written to the flash media and it
884 * is put just to make later in-memory string processing simpler. Thus,
885 * data length is @len, not @len + %1.
886 */
887 ui->data_len = len;
888 inode->i_size = ubifs_inode(inode)->ui_size = len;
889
890 mutex_lock(&dir_ui->ui_mutex);
891 dir->i_size += sz_change;
892 dir_ui->ui_size = dir->i_size;
893 dir->i_mtime = dir->i_ctime = inode->i_ctime;
894 err = ubifs_jnl_update(c, dir, &dentry->d_name, inode, 0, 0);
895 if (err)
896 goto out_cancel;
897 mutex_unlock(&dir_ui->ui_mutex);
898
899 ubifs_release_budget(c, &req);
900 insert_inode_hash(inode);
901 d_instantiate(dentry, inode);
902 return 0;
903
904out_cancel:
905 dir->i_size -= sz_change;
906 dir_ui->ui_size = dir->i_size;
907 mutex_unlock(&dir_ui->ui_mutex);
908out_inode:
909 make_bad_inode(inode);
910 iput(inode);
911out_budg:
912 ubifs_release_budget(c, &req);
913 return err;
914}
915
916/**
Artem Bityutskiy82c15932009-01-20 16:46:02 +0200917 * lock_3_inodes - a wrapper for locking three UBIFS inodes.
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300918 * @inode1: first inode
919 * @inode2: second inode
920 * @inode3: third inode
921 *
Artem Bityutskiy82c15932009-01-20 16:46:02 +0200922 * This function is used for 'ubifs_rename()' and @inode1 may be the same as
923 * @inode2 whereas @inode3 may be %NULL.
924 *
925 * We do not implement any tricks to guarantee strict lock ordering, because
926 * VFS has already done it for us on the @i_mutex. So this is just a simple
927 * wrapper function.
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300928 */
929static void lock_3_inodes(struct inode *inode1, struct inode *inode2,
930 struct inode *inode3)
931{
Artem Bityutskiy82c15932009-01-20 16:46:02 +0200932 mutex_lock_nested(&ubifs_inode(inode1)->ui_mutex, WB_MUTEX_1);
933 if (inode2 != inode1)
934 mutex_lock_nested(&ubifs_inode(inode2)->ui_mutex, WB_MUTEX_2);
935 if (inode3)
936 mutex_lock_nested(&ubifs_inode(inode3)->ui_mutex, WB_MUTEX_3);
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300937}
938
939/**
Artem Bityutskiy82c15932009-01-20 16:46:02 +0200940 * unlock_3_inodes - a wrapper for unlocking three UBIFS inodes for rename.
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300941 * @inode1: first inode
942 * @inode2: second inode
943 * @inode3: third inode
944 */
945static void unlock_3_inodes(struct inode *inode1, struct inode *inode2,
946 struct inode *inode3)
947{
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300948 if (inode3)
949 mutex_unlock(&ubifs_inode(inode3)->ui_mutex);
Artem Bityutskiy82c15932009-01-20 16:46:02 +0200950 if (inode1 != inode2)
951 mutex_unlock(&ubifs_inode(inode2)->ui_mutex);
952 mutex_unlock(&ubifs_inode(inode1)->ui_mutex);
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300953}
954
955static int ubifs_rename(struct inode *old_dir, struct dentry *old_dentry,
956 struct inode *new_dir, struct dentry *new_dentry)
957{
958 struct ubifs_info *c = old_dir->i_sb->s_fs_info;
959 struct inode *old_inode = old_dentry->d_inode;
960 struct inode *new_inode = new_dentry->d_inode;
961 struct ubifs_inode *old_inode_ui = ubifs_inode(old_inode);
962 int err, release, sync = 0, move = (new_dir != old_dir);
963 int is_dir = S_ISDIR(old_inode->i_mode);
964 int unlink = !!new_inode;
965 int new_sz = CALC_DENT_SIZE(new_dentry->d_name.len);
966 int old_sz = CALC_DENT_SIZE(old_dentry->d_name.len);
967 struct ubifs_budget_req req = { .new_dent = 1, .mod_dent = 1,
968 .dirtied_ino = 3 };
969 struct ubifs_budget_req ino_req = { .dirtied_ino = 1,
Artem Bityutskiydab4b4d2008-07-24 14:52:45 +0300970 .dirtied_ino_d = ALIGN(old_inode_ui->data_len, 8) };
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300971 struct timespec time;
Alexandre Pereira da Silva782759b2012-06-25 17:47:49 -0300972 unsigned int uninitialized_var(saved_nlink);
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300973
974 /*
975 * Budget request settings: deletion direntry, new direntry, removing
976 * the old inode, and changing old and new parent directory inodes.
977 *
978 * However, this operation also marks the target inode as dirty and
979 * does not write it, so we allocate budget for the target inode
980 * separately.
981 */
982
Artem Bityutskiy79fda512012-08-27 13:34:09 +0300983 dbg_gen("dent '%.*s' ino %lu in dir ino %lu to dent '%.*s' in dir ino %lu",
984 old_dentry->d_name.len, old_dentry->d_name.name,
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300985 old_inode->i_ino, old_dir->i_ino, new_dentry->d_name.len,
986 new_dentry->d_name.name, new_dir->i_ino);
Artem Bityutskiy82c15932009-01-20 16:46:02 +0200987 ubifs_assert(mutex_is_locked(&old_dir->i_mutex));
988 ubifs_assert(mutex_is_locked(&new_dir->i_mutex));
989 if (unlink)
990 ubifs_assert(mutex_is_locked(&new_inode->i_mutex));
991
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300992
993 if (unlink && is_dir) {
994 err = check_dir_empty(c, new_inode);
995 if (err)
996 return err;
997 }
998
999 err = ubifs_budget_space(c, &req);
1000 if (err)
1001 return err;
1002 err = ubifs_budget_space(c, &ino_req);
1003 if (err) {
1004 ubifs_release_budget(c, &req);
1005 return err;
1006 }
1007
1008 lock_3_inodes(old_dir, new_dir, new_inode);
1009
1010 /*
1011 * Like most other Unix systems, set the @i_ctime for inodes on a
1012 * rename.
1013 */
1014 time = ubifs_current_time(old_dir);
1015 old_inode->i_ctime = time;
1016
1017 /* We must adjust parent link count when renaming directories */
1018 if (is_dir) {
1019 if (move) {
1020 /*
1021 * @old_dir loses a link because we are moving
1022 * @old_inode to a different directory.
1023 */
1024 drop_nlink(old_dir);
1025 /*
1026 * @new_dir only gains a link if we are not also
1027 * overwriting an existing directory.
1028 */
1029 if (!unlink)
1030 inc_nlink(new_dir);
1031 } else {
1032 /*
1033 * @old_inode is not moving to a different directory,
1034 * but @old_dir still loses a link if we are
1035 * overwriting an existing directory.
1036 */
1037 if (unlink)
1038 drop_nlink(old_dir);
1039 }
1040 }
1041
1042 old_dir->i_size -= old_sz;
1043 ubifs_inode(old_dir)->ui_size = old_dir->i_size;
1044 old_dir->i_mtime = old_dir->i_ctime = time;
1045 new_dir->i_mtime = new_dir->i_ctime = time;
1046
1047 /*
1048 * And finally, if we unlinked a direntry which happened to have the
1049 * same name as the moved direntry, we have to decrement @i_nlink of
1050 * the unlinked inode and change its ctime.
1051 */
1052 if (unlink) {
1053 /*
1054 * Directories cannot have hard-links, so if this is a
Artem Bityutskiyc43be102012-02-07 10:58:51 +02001055 * directory, just clear @i_nlink.
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001056 */
Artem Bityutskiyc43be102012-02-07 10:58:51 +02001057 saved_nlink = new_inode->i_nlink;
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001058 if (is_dir)
Artem Bityutskiyc43be102012-02-07 10:58:51 +02001059 clear_nlink(new_inode);
1060 else
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001061 drop_nlink(new_inode);
1062 new_inode->i_ctime = time;
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001063 } else {
1064 new_dir->i_size += new_sz;
1065 ubifs_inode(new_dir)->ui_size = new_dir->i_size;
1066 }
1067
1068 /*
1069 * Do not ask 'ubifs_jnl_rename()' to flush write-buffer if @old_inode
1070 * is dirty, because this will be done later on at the end of
1071 * 'ubifs_rename()'.
1072 */
1073 if (IS_SYNC(old_inode)) {
1074 sync = IS_DIRSYNC(old_dir) || IS_DIRSYNC(new_dir);
1075 if (unlink && IS_SYNC(new_inode))
1076 sync = 1;
1077 }
1078 err = ubifs_jnl_rename(c, old_dir, old_dentry, new_dir, new_dentry,
1079 sync);
1080 if (err)
1081 goto out_cancel;
1082
1083 unlock_3_inodes(old_dir, new_dir, new_inode);
1084 ubifs_release_budget(c, &req);
1085
1086 mutex_lock(&old_inode_ui->ui_mutex);
1087 release = old_inode_ui->dirty;
1088 mark_inode_dirty_sync(old_inode);
1089 mutex_unlock(&old_inode_ui->ui_mutex);
1090
1091 if (release)
1092 ubifs_release_budget(c, &ino_req);
1093 if (IS_SYNC(old_inode))
Christoph Hellwiga9185b42010-03-05 09:21:37 +01001094 err = old_inode->i_sb->s_op->write_inode(old_inode, NULL);
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001095 return err;
1096
1097out_cancel:
1098 if (unlink) {
Artem Bityutskiyc43be102012-02-07 10:58:51 +02001099 set_nlink(new_inode, saved_nlink);
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001100 } else {
1101 new_dir->i_size -= new_sz;
1102 ubifs_inode(new_dir)->ui_size = new_dir->i_size;
1103 }
1104 old_dir->i_size += old_sz;
1105 ubifs_inode(old_dir)->ui_size = old_dir->i_size;
1106 if (is_dir) {
1107 if (move) {
1108 inc_nlink(old_dir);
1109 if (!unlink)
1110 drop_nlink(new_dir);
1111 } else {
1112 if (unlink)
1113 inc_nlink(old_dir);
1114 }
1115 }
1116 unlock_3_inodes(old_dir, new_dir, new_inode);
1117 ubifs_release_budget(c, &ino_req);
1118 ubifs_release_budget(c, &req);
1119 return err;
1120}
1121
1122int ubifs_getattr(struct vfsmount *mnt, struct dentry *dentry,
1123 struct kstat *stat)
1124{
1125 loff_t size;
1126 struct inode *inode = dentry->d_inode;
1127 struct ubifs_inode *ui = ubifs_inode(inode);
1128
1129 mutex_lock(&ui->ui_mutex);
Al Viro6d42e7e2012-04-02 14:25:07 -04001130 generic_fillattr(inode, stat);
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001131 stat->blksize = UBIFS_BLOCK_SIZE;
1132 stat->size = ui->ui_size;
1133
1134 /*
1135 * Unfortunately, the 'stat()' system call was designed for block
1136 * device based file systems, and it is not appropriate for UBIFS,
1137 * because UBIFS does not have notion of "block". For example, it is
1138 * difficult to tell how many block a directory takes - it actually
1139 * takes less than 300 bytes, but we have to round it to block size,
1140 * which introduces large mistake. This makes utilities like 'du' to
1141 * report completely senseless numbers. This is the reason why UBIFS
1142 * goes the same way as JFFS2 - it reports zero blocks for everything
1143 * but regular files, which makes more sense than reporting completely
1144 * wrong sizes.
1145 */
1146 if (S_ISREG(inode->i_mode)) {
1147 size = ui->xattr_size;
1148 size += stat->size;
1149 size = ALIGN(size, UBIFS_BLOCK_SIZE);
1150 /*
1151 * Note, user-space expects 512-byte blocks count irrespectively
1152 * of what was reported in @stat->size.
1153 */
1154 stat->blocks = size >> 9;
1155 } else
1156 stat->blocks = 0;
1157 mutex_unlock(&ui->ui_mutex);
1158 return 0;
1159}
1160
Artem Bityutskiye8b81562009-01-15 17:43:23 +02001161const struct inode_operations ubifs_dir_inode_operations = {
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001162 .lookup = ubifs_lookup,
1163 .create = ubifs_create,
1164 .link = ubifs_link,
1165 .symlink = ubifs_symlink,
1166 .unlink = ubifs_unlink,
1167 .mkdir = ubifs_mkdir,
1168 .rmdir = ubifs_rmdir,
1169 .mknod = ubifs_mknod,
1170 .rename = ubifs_rename,
1171 .setattr = ubifs_setattr,
1172 .getattr = ubifs_getattr,
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001173 .setxattr = ubifs_setxattr,
1174 .getxattr = ubifs_getxattr,
1175 .listxattr = ubifs_listxattr,
1176 .removexattr = ubifs_removexattr,
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001177};
1178
Artem Bityutskiye8b81562009-01-15 17:43:23 +02001179const struct file_operations ubifs_dir_operations = {
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001180 .llseek = ubifs_dir_llseek,
1181 .release = ubifs_dir_release,
1182 .read = generic_read_dir,
1183 .readdir = ubifs_readdir,
1184 .fsync = ubifs_fsync,
1185 .unlocked_ioctl = ubifs_ioctl,
1186#ifdef CONFIG_COMPAT
1187 .compat_ioctl = ubifs_compat_ioctl,
1188#endif
1189};