1 /* * This file is part of UBIFS.
3 * Copyright (C) 2006-2008 Nokia Corporation.
4 * Copyright (C) 2006, 2007 University of Szeged, Hungary
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.
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
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
19 * Authors: Artem Bityutskiy (Битюцкий Артём)
25 * This file implements directory operations.
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.
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.
46 * inherit_flags - inherit flags of the parent inode.
48 * @mode: new inode mode flags
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.
57 * This function returns the inherited flags.
59 static int inherit_flags(const struct inode *dir, umode_t mode)
62 const struct ubifs_inode *ui = ubifs_inode(dir);
64 if (!S_ISDIR(dir->i_mode))
66 * The parent is not a directory, which means that an extended
67 * attribute inode is being created. No flags.
71 flags = ui->flags & (UBIFS_COMPR_FL | UBIFS_SYNC_FL | UBIFS_DIRSYNC_FL);
73 /* The "DIRSYNC" flag only applies to directories */
74 flags &= ~UBIFS_DIRSYNC_FL;
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
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
88 struct inode *ubifs_new_inode(struct ubifs_info *c, const struct inode *dir,
92 struct ubifs_inode *ui;
94 inode = new_inode(c->vfs_sb);
95 ui = ubifs_inode(inode);
97 return ERR_PTR(-ENOMEM);
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.
105 inode->i_flags |= S_NOCMTIME;
107 inode_init_owner(inode, dir, mode);
108 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;
114 switch (mode & S_IFMT) {
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;
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;
126 inode->i_op = &ubifs_symlink_inode_operations;
132 inode->i_op = &ubifs_file_inode_operations;
138 ui->flags = inherit_flags(dir, mode);
139 ubifs_set_inode_flags(inode);
141 ui->compr_type = c->default_compr;
143 ui->compr_type = UBIFS_COMPR_NONE;
144 ui->synced_i_size = 0;
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);
154 return ERR_PTR(-EINVAL);
156 ubifs_warn("running out of inode numbers (current %lu, max %d)",
157 (unsigned long)c->highest_inum, INUM_WATERMARK);
160 inode->i_ino = ++c->highest_inum;
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.
168 ui->creat_sqnum = ++c->max_sqnum;
169 spin_unlock(&c->cnt_lock);
173 static int dbg_check_name(const struct ubifs_info *c,
174 const struct ubifs_dent_node *dent,
175 const struct qstr *nm)
177 if (!dbg_is_chk_gen(c))
179 if (le16_to_cpu(dent->nlen) != nm->len)
181 if (memcmp(dent->name, nm->name, nm->len))
186 static struct dentry *ubifs_lookup(struct inode *dir, struct dentry *dentry,
191 struct inode *inode = NULL;
192 struct ubifs_dent_node *dent;
193 struct ubifs_info *c = dir->i_sb->s_fs_info;
195 dbg_gen("'%pd' in dir ino %lu", dentry, dir->i_ino);
197 if (dentry->d_name.len > UBIFS_MAX_NLEN)
198 return ERR_PTR(-ENAMETOOLONG);
200 dent = kmalloc(UBIFS_MAX_DENT_NODE_SZ, GFP_NOFS);
202 return ERR_PTR(-ENOMEM);
204 dent_key_init(c, &key, dir->i_ino, &dentry->d_name);
206 err = ubifs_tnc_lookup_nm(c, &key, dent, &dentry->d_name);
208 if (err == -ENOENT) {
209 dbg_gen("not found");
215 if (dbg_check_name(c, dent, &dentry->d_name)) {
220 inode = ubifs_iget(dir->i_sb, le64_to_cpu(dent->inum));
223 * This should not happen. Probably the file-system needs
226 err = PTR_ERR(inode);
227 ubifs_err("dead directory entry '%pd', error %d",
229 ubifs_ro_mode(c, err);
236 * Note, d_splice_alias() would be required instead if we supported
239 d_add(dentry, inode);
247 static int ubifs_create(struct inode *dir, struct dentry *dentry, umode_t mode,
251 struct ubifs_info *c = dir->i_sb->s_fs_info;
252 int err, sz_change = CALC_DENT_SIZE(dentry->d_name.len);
253 struct ubifs_budget_req req = { .new_ino = 1, .new_dent = 1,
255 struct ubifs_inode *dir_ui = ubifs_inode(dir);
258 * Budget request settings: new inode, new direntry, changing the
259 * parent directory inode.
262 dbg_gen("dent '%pd', mode %#hx in dir ino %lu",
263 dentry, mode, dir->i_ino);
265 err = ubifs_budget_space(c, &req);
269 inode = ubifs_new_inode(c, dir, mode);
271 err = PTR_ERR(inode);
275 mutex_lock(&dir_ui->ui_mutex);
276 dir->i_size += sz_change;
277 dir_ui->ui_size = dir->i_size;
278 dir->i_mtime = dir->i_ctime = inode->i_ctime;
279 err = ubifs_jnl_update(c, dir, &dentry->d_name, inode, 0, 0);
282 mutex_unlock(&dir_ui->ui_mutex);
284 ubifs_release_budget(c, &req);
285 insert_inode_hash(inode);
286 d_instantiate(dentry, inode);
290 dir->i_size -= sz_change;
291 dir_ui->ui_size = dir->i_size;
292 mutex_unlock(&dir_ui->ui_mutex);
293 make_bad_inode(inode);
296 ubifs_release_budget(c, &req);
297 ubifs_err("cannot create regular file, error %d", err);
302 * vfs_dent_type - get VFS directory entry type.
303 * @type: UBIFS directory entry type
305 * This function converts UBIFS directory entry type into VFS directory entry
308 static unsigned int vfs_dent_type(uint8_t type)
311 case UBIFS_ITYPE_REG:
313 case UBIFS_ITYPE_DIR:
315 case UBIFS_ITYPE_LNK:
317 case UBIFS_ITYPE_BLK:
319 case UBIFS_ITYPE_CHR:
321 case UBIFS_ITYPE_FIFO:
323 case UBIFS_ITYPE_SOCK:
332 * The classical Unix view for directory is that it is a linear array of
333 * (name, inode number) entries. Linux/VFS assumes this model as well.
334 * Particularly, 'readdir()' call wants us to return a directory entry offset
335 * which later may be used to continue 'readdir()'ing the directory or to
336 * 'seek()' to that specific direntry. Obviously UBIFS does not really fit this
337 * model because directory entries are identified by keys, which may collide.
339 * UBIFS uses directory entry hash value for directory offsets, so
340 * 'seekdir()'/'telldir()' may not always work because of possible key
341 * collisions. But UBIFS guarantees that consecutive 'readdir()' calls work
342 * properly by means of saving full directory entry name in the private field
343 * of the file description object.
345 * This means that UBIFS cannot support NFS which requires full
346 * 'seekdir()'/'telldir()' support.
348 static int ubifs_readdir(struct file *file, struct dir_context *ctx)
353 struct ubifs_dent_node *dent;
354 struct inode *dir = file_inode(file);
355 struct ubifs_info *c = dir->i_sb->s_fs_info;
357 dbg_gen("dir ino %lu, f_pos %#llx", dir->i_ino, ctx->pos);
359 if (ctx->pos > UBIFS_S_KEY_HASH_MASK || ctx->pos == 2)
361 * The directory was seek'ed to a senseless position or there
362 * are no more entries.
366 if (file->f_version == 0) {
368 * The file was seek'ed, which means that @file->private_data
369 * is now invalid. This may also be just the first
370 * 'ubifs_readdir()' invocation, in which case
371 * @file->private_data is NULL, and the below code is
374 kfree(file->private_data);
375 file->private_data = NULL;
379 * 'generic_file_llseek()' unconditionally sets @file->f_version to
380 * zero, and we use this for detecting whether the file was seek'ed.
384 /* File positions 0 and 1 correspond to "." and ".." */
386 ubifs_assert(!file->private_data);
387 if (!dir_emit_dots(file, ctx))
390 /* Find the first entry in TNC and save it */
391 lowest_dent_key(c, &key, dir->i_ino);
393 dent = ubifs_tnc_next_ent(c, &key, &nm);
399 ctx->pos = key_hash_flash(c, &dent->key);
400 file->private_data = dent;
403 dent = file->private_data;
406 * The directory was seek'ed to and is now readdir'ed.
407 * Find the entry corresponding to @ctx->pos or the closest one.
409 dent_key_init_hash(c, &key, dir->i_ino, ctx->pos);
411 dent = ubifs_tnc_next_ent(c, &key, &nm);
416 ctx->pos = key_hash_flash(c, &dent->key);
417 file->private_data = dent;
421 dbg_gen("feed '%s', ino %llu, new f_pos %#x",
422 dent->name, (unsigned long long)le64_to_cpu(dent->inum),
423 key_hash_flash(c, &dent->key));
424 ubifs_assert(le64_to_cpu(dent->ch.sqnum) >
425 ubifs_inode(dir)->creat_sqnum);
427 nm.len = le16_to_cpu(dent->nlen);
428 if (!dir_emit(ctx, dent->name, nm.len,
429 le64_to_cpu(dent->inum),
430 vfs_dent_type(dent->type)))
433 /* Switch to the next entry */
434 key_read(c, &dent->key, &key);
435 nm.name = dent->name;
436 dent = ubifs_tnc_next_ent(c, &key, &nm);
442 kfree(file->private_data);
443 ctx->pos = key_hash_flash(c, &dent->key);
444 file->private_data = dent;
449 if (err != -ENOENT) {
450 ubifs_err("cannot find next direntry, error %d", err);
454 kfree(file->private_data);
455 file->private_data = NULL;
456 /* 2 is a special value indicating that there are no more direntries */
461 /* Free saved readdir() state when the directory is closed */
462 static int ubifs_dir_release(struct inode *dir, struct file *file)
464 kfree(file->private_data);
465 file->private_data = NULL;
470 * lock_2_inodes - a wrapper for locking two UBIFS inodes.
471 * @inode1: first inode
472 * @inode2: second inode
474 * We do not implement any tricks to guarantee strict lock ordering, because
475 * VFS has already done it for us on the @i_mutex. So this is just a simple
478 static void lock_2_inodes(struct inode *inode1, struct inode *inode2)
480 mutex_lock_nested(&ubifs_inode(inode1)->ui_mutex, WB_MUTEX_1);
481 mutex_lock_nested(&ubifs_inode(inode2)->ui_mutex, WB_MUTEX_2);
485 * unlock_2_inodes - a wrapper for unlocking two UBIFS inodes.
486 * @inode1: first inode
487 * @inode2: second inode
489 static void unlock_2_inodes(struct inode *inode1, struct inode *inode2)
491 mutex_unlock(&ubifs_inode(inode2)->ui_mutex);
492 mutex_unlock(&ubifs_inode(inode1)->ui_mutex);
495 static int ubifs_link(struct dentry *old_dentry, struct inode *dir,
496 struct dentry *dentry)
498 struct ubifs_info *c = dir->i_sb->s_fs_info;
499 struct inode *inode = old_dentry->d_inode;
500 struct ubifs_inode *ui = ubifs_inode(inode);
501 struct ubifs_inode *dir_ui = ubifs_inode(dir);
502 int err, sz_change = CALC_DENT_SIZE(dentry->d_name.len);
503 struct ubifs_budget_req req = { .new_dent = 1, .dirtied_ino = 2,
504 .dirtied_ino_d = ALIGN(ui->data_len, 8) };
507 * Budget request settings: new direntry, changing the target inode,
508 * changing the parent inode.
511 dbg_gen("dent '%pd' to ino %lu (nlink %d) in dir ino %lu",
512 dentry, inode->i_ino,
513 inode->i_nlink, dir->i_ino);
514 ubifs_assert(mutex_is_locked(&dir->i_mutex));
515 ubifs_assert(mutex_is_locked(&inode->i_mutex));
517 err = dbg_check_synced_i_size(c, inode);
521 err = ubifs_budget_space(c, &req);
525 lock_2_inodes(dir, inode);
528 inode->i_ctime = ubifs_current_time(inode);
529 dir->i_size += sz_change;
530 dir_ui->ui_size = dir->i_size;
531 dir->i_mtime = dir->i_ctime = inode->i_ctime;
532 err = ubifs_jnl_update(c, dir, &dentry->d_name, inode, 0, 0);
535 unlock_2_inodes(dir, inode);
537 ubifs_release_budget(c, &req);
538 d_instantiate(dentry, inode);
542 dir->i_size -= sz_change;
543 dir_ui->ui_size = dir->i_size;
545 unlock_2_inodes(dir, inode);
546 ubifs_release_budget(c, &req);
551 static int ubifs_unlink(struct inode *dir, struct dentry *dentry)
553 struct ubifs_info *c = dir->i_sb->s_fs_info;
554 struct inode *inode = dentry->d_inode;
555 struct ubifs_inode *dir_ui = ubifs_inode(dir);
556 int sz_change = CALC_DENT_SIZE(dentry->d_name.len);
557 int err, budgeted = 1;
558 struct ubifs_budget_req req = { .mod_dent = 1, .dirtied_ino = 2 };
559 unsigned int saved_nlink = inode->i_nlink;
562 * Budget request settings: deletion direntry, deletion inode (+1 for
563 * @dirtied_ino), changing the parent directory inode. If budgeting
564 * fails, go ahead anyway because we have extra space reserved for
568 dbg_gen("dent '%pd' from ino %lu (nlink %d) in dir ino %lu",
569 dentry, inode->i_ino,
570 inode->i_nlink, dir->i_ino);
571 ubifs_assert(mutex_is_locked(&dir->i_mutex));
572 ubifs_assert(mutex_is_locked(&inode->i_mutex));
573 err = dbg_check_synced_i_size(c, inode);
577 err = ubifs_budget_space(c, &req);
584 lock_2_inodes(dir, inode);
585 inode->i_ctime = ubifs_current_time(dir);
587 dir->i_size -= sz_change;
588 dir_ui->ui_size = dir->i_size;
589 dir->i_mtime = dir->i_ctime = inode->i_ctime;
590 err = ubifs_jnl_update(c, dir, &dentry->d_name, inode, 1, 0);
593 unlock_2_inodes(dir, inode);
596 ubifs_release_budget(c, &req);
598 /* We've deleted something - clean the "no space" flags */
599 c->bi.nospace = c->bi.nospace_rp = 0;
605 dir->i_size += sz_change;
606 dir_ui->ui_size = dir->i_size;
607 set_nlink(inode, saved_nlink);
608 unlock_2_inodes(dir, inode);
610 ubifs_release_budget(c, &req);
615 * check_dir_empty - check if a directory is empty or not.
616 * @c: UBIFS file-system description object
617 * @dir: VFS inode object of the directory to check
619 * This function checks if directory @dir is empty. Returns zero if the
620 * directory is empty, %-ENOTEMPTY if it is not, and other negative error codes
621 * in case of of errors.
623 static int check_dir_empty(struct ubifs_info *c, struct inode *dir)
625 struct qstr nm = { .name = NULL };
626 struct ubifs_dent_node *dent;
630 lowest_dent_key(c, &key, dir->i_ino);
631 dent = ubifs_tnc_next_ent(c, &key, &nm);
643 static int ubifs_rmdir(struct inode *dir, struct dentry *dentry)
645 struct ubifs_info *c = dir->i_sb->s_fs_info;
646 struct inode *inode = dentry->d_inode;
647 int sz_change = CALC_DENT_SIZE(dentry->d_name.len);
648 int err, budgeted = 1;
649 struct ubifs_inode *dir_ui = ubifs_inode(dir);
650 struct ubifs_budget_req req = { .mod_dent = 1, .dirtied_ino = 2 };
653 * Budget request settings: deletion direntry, deletion inode and
654 * changing the parent inode. If budgeting fails, go ahead anyway
655 * because we have extra space reserved for deletions.
658 dbg_gen("directory '%pd', ino %lu in dir ino %lu", dentry,
659 inode->i_ino, dir->i_ino);
660 ubifs_assert(mutex_is_locked(&dir->i_mutex));
661 ubifs_assert(mutex_is_locked(&inode->i_mutex));
662 err = check_dir_empty(c, dentry->d_inode);
666 err = ubifs_budget_space(c, &req);
673 lock_2_inodes(dir, inode);
674 inode->i_ctime = ubifs_current_time(dir);
677 dir->i_size -= sz_change;
678 dir_ui->ui_size = dir->i_size;
679 dir->i_mtime = dir->i_ctime = inode->i_ctime;
680 err = ubifs_jnl_update(c, dir, &dentry->d_name, inode, 1, 0);
683 unlock_2_inodes(dir, inode);
686 ubifs_release_budget(c, &req);
688 /* We've deleted something - clean the "no space" flags */
689 c->bi.nospace = c->bi.nospace_rp = 0;
695 dir->i_size += sz_change;
696 dir_ui->ui_size = dir->i_size;
699 unlock_2_inodes(dir, inode);
701 ubifs_release_budget(c, &req);
705 static int ubifs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
708 struct ubifs_inode *dir_ui = ubifs_inode(dir);
709 struct ubifs_info *c = dir->i_sb->s_fs_info;
710 int err, sz_change = CALC_DENT_SIZE(dentry->d_name.len);
711 struct ubifs_budget_req req = { .new_ino = 1, .new_dent = 1 };
714 * Budget request settings: new inode, new direntry and changing parent
718 dbg_gen("dent '%pd', mode %#hx in dir ino %lu",
719 dentry, mode, dir->i_ino);
721 err = ubifs_budget_space(c, &req);
725 inode = ubifs_new_inode(c, dir, S_IFDIR | mode);
727 err = PTR_ERR(inode);
731 mutex_lock(&dir_ui->ui_mutex);
732 insert_inode_hash(inode);
735 dir->i_size += sz_change;
736 dir_ui->ui_size = dir->i_size;
737 dir->i_mtime = dir->i_ctime = inode->i_ctime;
738 err = ubifs_jnl_update(c, dir, &dentry->d_name, inode, 0, 0);
740 ubifs_err("cannot create directory, error %d", err);
743 mutex_unlock(&dir_ui->ui_mutex);
745 ubifs_release_budget(c, &req);
746 d_instantiate(dentry, inode);
750 dir->i_size -= sz_change;
751 dir_ui->ui_size = dir->i_size;
753 mutex_unlock(&dir_ui->ui_mutex);
754 make_bad_inode(inode);
757 ubifs_release_budget(c, &req);
761 static int ubifs_mknod(struct inode *dir, struct dentry *dentry,
762 umode_t mode, dev_t rdev)
765 struct ubifs_inode *ui;
766 struct ubifs_inode *dir_ui = ubifs_inode(dir);
767 struct ubifs_info *c = dir->i_sb->s_fs_info;
768 union ubifs_dev_desc *dev = NULL;
769 int sz_change = CALC_DENT_SIZE(dentry->d_name.len);
771 struct ubifs_budget_req req = { .new_ino = 1, .new_dent = 1,
772 .new_ino_d = ALIGN(devlen, 8),
776 * Budget request settings: new inode, new direntry and changing parent
780 dbg_gen("dent '%pd' in dir ino %lu", dentry, dir->i_ino);
782 if (!new_valid_dev(rdev))
785 if (S_ISBLK(mode) || S_ISCHR(mode)) {
786 dev = kmalloc(sizeof(union ubifs_dev_desc), GFP_NOFS);
789 devlen = ubifs_encode_dev(dev, rdev);
792 err = ubifs_budget_space(c, &req);
798 inode = ubifs_new_inode(c, dir, mode);
801 err = PTR_ERR(inode);
805 init_special_inode(inode, inode->i_mode, rdev);
806 inode->i_size = ubifs_inode(inode)->ui_size = devlen;
807 ui = ubifs_inode(inode);
809 ui->data_len = devlen;
811 mutex_lock(&dir_ui->ui_mutex);
812 dir->i_size += sz_change;
813 dir_ui->ui_size = dir->i_size;
814 dir->i_mtime = dir->i_ctime = inode->i_ctime;
815 err = ubifs_jnl_update(c, dir, &dentry->d_name, inode, 0, 0);
818 mutex_unlock(&dir_ui->ui_mutex);
820 ubifs_release_budget(c, &req);
821 insert_inode_hash(inode);
822 d_instantiate(dentry, inode);
826 dir->i_size -= sz_change;
827 dir_ui->ui_size = dir->i_size;
828 mutex_unlock(&dir_ui->ui_mutex);
829 make_bad_inode(inode);
832 ubifs_release_budget(c, &req);
836 static int ubifs_symlink(struct inode *dir, struct dentry *dentry,
840 struct ubifs_inode *ui;
841 struct ubifs_inode *dir_ui = ubifs_inode(dir);
842 struct ubifs_info *c = dir->i_sb->s_fs_info;
843 int err, len = strlen(symname);
844 int sz_change = CALC_DENT_SIZE(dentry->d_name.len);
845 struct ubifs_budget_req req = { .new_ino = 1, .new_dent = 1,
846 .new_ino_d = ALIGN(len, 8),
850 * Budget request settings: new inode, new direntry and changing parent
854 dbg_gen("dent '%pd', target '%s' in dir ino %lu", dentry,
855 symname, dir->i_ino);
857 if (len > UBIFS_MAX_INO_DATA)
858 return -ENAMETOOLONG;
860 err = ubifs_budget_space(c, &req);
864 inode = ubifs_new_inode(c, dir, S_IFLNK | S_IRWXUGO);
866 err = PTR_ERR(inode);
870 ui = ubifs_inode(inode);
871 ui->data = kmalloc(len + 1, GFP_NOFS);
877 memcpy(ui->data, symname, len);
878 ((char *)ui->data)[len] = '\0';
880 * The terminating zero byte is not written to the flash media and it
881 * is put just to make later in-memory string processing simpler. Thus,
882 * data length is @len, not @len + %1.
885 inode->i_size = ubifs_inode(inode)->ui_size = len;
887 mutex_lock(&dir_ui->ui_mutex);
888 dir->i_size += sz_change;
889 dir_ui->ui_size = dir->i_size;
890 dir->i_mtime = dir->i_ctime = inode->i_ctime;
891 err = ubifs_jnl_update(c, dir, &dentry->d_name, inode, 0, 0);
894 mutex_unlock(&dir_ui->ui_mutex);
896 ubifs_release_budget(c, &req);
897 insert_inode_hash(inode);
898 d_instantiate(dentry, inode);
902 dir->i_size -= sz_change;
903 dir_ui->ui_size = dir->i_size;
904 mutex_unlock(&dir_ui->ui_mutex);
906 make_bad_inode(inode);
909 ubifs_release_budget(c, &req);
914 * lock_3_inodes - a wrapper for locking three UBIFS inodes.
915 * @inode1: first inode
916 * @inode2: second inode
917 * @inode3: third inode
919 * This function is used for 'ubifs_rename()' and @inode1 may be the same as
920 * @inode2 whereas @inode3 may be %NULL.
922 * We do not implement any tricks to guarantee strict lock ordering, because
923 * VFS has already done it for us on the @i_mutex. So this is just a simple
926 static void lock_3_inodes(struct inode *inode1, struct inode *inode2,
927 struct inode *inode3)
929 mutex_lock_nested(&ubifs_inode(inode1)->ui_mutex, WB_MUTEX_1);
930 if (inode2 != inode1)
931 mutex_lock_nested(&ubifs_inode(inode2)->ui_mutex, WB_MUTEX_2);
933 mutex_lock_nested(&ubifs_inode(inode3)->ui_mutex, WB_MUTEX_3);
937 * unlock_3_inodes - a wrapper for unlocking three UBIFS inodes for rename.
938 * @inode1: first inode
939 * @inode2: second inode
940 * @inode3: third inode
942 static void unlock_3_inodes(struct inode *inode1, struct inode *inode2,
943 struct inode *inode3)
946 mutex_unlock(&ubifs_inode(inode3)->ui_mutex);
947 if (inode1 != inode2)
948 mutex_unlock(&ubifs_inode(inode2)->ui_mutex);
949 mutex_unlock(&ubifs_inode(inode1)->ui_mutex);
952 static int ubifs_rename(struct inode *old_dir, struct dentry *old_dentry,
953 struct inode *new_dir, struct dentry *new_dentry)
955 struct ubifs_info *c = old_dir->i_sb->s_fs_info;
956 struct inode *old_inode = old_dentry->d_inode;
957 struct inode *new_inode = new_dentry->d_inode;
958 struct ubifs_inode *old_inode_ui = ubifs_inode(old_inode);
959 int err, release, sync = 0, move = (new_dir != old_dir);
960 int is_dir = S_ISDIR(old_inode->i_mode);
961 int unlink = !!new_inode;
962 int new_sz = CALC_DENT_SIZE(new_dentry->d_name.len);
963 int old_sz = CALC_DENT_SIZE(old_dentry->d_name.len);
964 struct ubifs_budget_req req = { .new_dent = 1, .mod_dent = 1,
966 struct ubifs_budget_req ino_req = { .dirtied_ino = 1,
967 .dirtied_ino_d = ALIGN(old_inode_ui->data_len, 8) };
968 struct timespec time;
969 unsigned int uninitialized_var(saved_nlink);
972 * Budget request settings: deletion direntry, new direntry, removing
973 * the old inode, and changing old and new parent directory inodes.
975 * However, this operation also marks the target inode as dirty and
976 * does not write it, so we allocate budget for the target inode
980 dbg_gen("dent '%pd' ino %lu in dir ino %lu to dent '%pd' in dir ino %lu",
981 old_dentry, old_inode->i_ino, old_dir->i_ino,
982 new_dentry, new_dir->i_ino);
983 ubifs_assert(mutex_is_locked(&old_dir->i_mutex));
984 ubifs_assert(mutex_is_locked(&new_dir->i_mutex));
986 ubifs_assert(mutex_is_locked(&new_inode->i_mutex));
989 if (unlink && is_dir) {
990 err = check_dir_empty(c, new_inode);
995 err = ubifs_budget_space(c, &req);
998 err = ubifs_budget_space(c, &ino_req);
1000 ubifs_release_budget(c, &req);
1004 lock_3_inodes(old_dir, new_dir, new_inode);
1007 * Like most other Unix systems, set the @i_ctime for inodes on a
1010 time = ubifs_current_time(old_dir);
1011 old_inode->i_ctime = time;
1013 /* We must adjust parent link count when renaming directories */
1017 * @old_dir loses a link because we are moving
1018 * @old_inode to a different directory.
1020 drop_nlink(old_dir);
1022 * @new_dir only gains a link if we are not also
1023 * overwriting an existing directory.
1029 * @old_inode is not moving to a different directory,
1030 * but @old_dir still loses a link if we are
1031 * overwriting an existing directory.
1034 drop_nlink(old_dir);
1038 old_dir->i_size -= old_sz;
1039 ubifs_inode(old_dir)->ui_size = old_dir->i_size;
1040 old_dir->i_mtime = old_dir->i_ctime = time;
1041 new_dir->i_mtime = new_dir->i_ctime = time;
1044 * And finally, if we unlinked a direntry which happened to have the
1045 * same name as the moved direntry, we have to decrement @i_nlink of
1046 * the unlinked inode and change its ctime.
1050 * Directories cannot have hard-links, so if this is a
1051 * directory, just clear @i_nlink.
1053 saved_nlink = new_inode->i_nlink;
1055 clear_nlink(new_inode);
1057 drop_nlink(new_inode);
1058 new_inode->i_ctime = time;
1060 new_dir->i_size += new_sz;
1061 ubifs_inode(new_dir)->ui_size = new_dir->i_size;
1065 * Do not ask 'ubifs_jnl_rename()' to flush write-buffer if @old_inode
1066 * is dirty, because this will be done later on at the end of
1069 if (IS_SYNC(old_inode)) {
1070 sync = IS_DIRSYNC(old_dir) || IS_DIRSYNC(new_dir);
1071 if (unlink && IS_SYNC(new_inode))
1074 err = ubifs_jnl_rename(c, old_dir, old_dentry, new_dir, new_dentry,
1079 unlock_3_inodes(old_dir, new_dir, new_inode);
1080 ubifs_release_budget(c, &req);
1082 mutex_lock(&old_inode_ui->ui_mutex);
1083 release = old_inode_ui->dirty;
1084 mark_inode_dirty_sync(old_inode);
1085 mutex_unlock(&old_inode_ui->ui_mutex);
1088 ubifs_release_budget(c, &ino_req);
1089 if (IS_SYNC(old_inode))
1090 err = old_inode->i_sb->s_op->write_inode(old_inode, NULL);
1095 set_nlink(new_inode, saved_nlink);
1097 new_dir->i_size -= new_sz;
1098 ubifs_inode(new_dir)->ui_size = new_dir->i_size;
1100 old_dir->i_size += old_sz;
1101 ubifs_inode(old_dir)->ui_size = old_dir->i_size;
1106 drop_nlink(new_dir);
1112 unlock_3_inodes(old_dir, new_dir, new_inode);
1113 ubifs_release_budget(c, &ino_req);
1114 ubifs_release_budget(c, &req);
1118 int ubifs_getattr(struct vfsmount *mnt, struct dentry *dentry,
1122 struct inode *inode = dentry->d_inode;
1123 struct ubifs_inode *ui = ubifs_inode(inode);
1125 mutex_lock(&ui->ui_mutex);
1126 generic_fillattr(inode, stat);
1127 stat->blksize = UBIFS_BLOCK_SIZE;
1128 stat->size = ui->ui_size;
1131 * Unfortunately, the 'stat()' system call was designed for block
1132 * device based file systems, and it is not appropriate for UBIFS,
1133 * because UBIFS does not have notion of "block". For example, it is
1134 * difficult to tell how many block a directory takes - it actually
1135 * takes less than 300 bytes, but we have to round it to block size,
1136 * which introduces large mistake. This makes utilities like 'du' to
1137 * report completely senseless numbers. This is the reason why UBIFS
1138 * goes the same way as JFFS2 - it reports zero blocks for everything
1139 * but regular files, which makes more sense than reporting completely
1142 if (S_ISREG(inode->i_mode)) {
1143 size = ui->xattr_size;
1145 size = ALIGN(size, UBIFS_BLOCK_SIZE);
1147 * Note, user-space expects 512-byte blocks count irrespectively
1148 * of what was reported in @stat->size.
1150 stat->blocks = size >> 9;
1153 mutex_unlock(&ui->ui_mutex);
1157 const struct inode_operations ubifs_dir_inode_operations = {
1158 .lookup = ubifs_lookup,
1159 .create = ubifs_create,
1161 .symlink = ubifs_symlink,
1162 .unlink = ubifs_unlink,
1163 .mkdir = ubifs_mkdir,
1164 .rmdir = ubifs_rmdir,
1165 .mknod = ubifs_mknod,
1166 .rename = ubifs_rename,
1167 .setattr = ubifs_setattr,
1168 .getattr = ubifs_getattr,
1169 .setxattr = ubifs_setxattr,
1170 .getxattr = ubifs_getxattr,
1171 .listxattr = ubifs_listxattr,
1172 .removexattr = ubifs_removexattr,
1175 const struct file_operations ubifs_dir_operations = {
1176 .llseek = generic_file_llseek,
1177 .release = ubifs_dir_release,
1178 .read = generic_read_dir,
1179 .iterate = ubifs_readdir,
1180 .fsync = ubifs_fsync,
1181 .unlocked_ioctl = ubifs_ioctl,
1182 #ifdef CONFIG_COMPAT
1183 .compat_ioctl = ubifs_compat_ioctl,