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;
112 switch (mode & S_IFMT) {
114 inode->i_mapping->a_ops = &ubifs_file_address_operations;
115 inode->i_op = &ubifs_file_inode_operations;
116 inode->i_fop = &ubifs_file_operations;
119 inode->i_op = &ubifs_dir_inode_operations;
120 inode->i_fop = &ubifs_dir_operations;
121 inode->i_size = ui->ui_size = UBIFS_INO_NODE_SZ;
124 inode->i_op = &ubifs_symlink_inode_operations;
130 inode->i_op = &ubifs_file_inode_operations;
136 ui->flags = inherit_flags(dir, mode);
137 ubifs_set_inode_flags(inode);
139 ui->compr_type = c->default_compr;
141 ui->compr_type = UBIFS_COMPR_NONE;
142 ui->synced_i_size = 0;
144 spin_lock(&c->cnt_lock);
145 /* Inode number overflow is currently not supported */
146 if (c->highest_inum >= INUM_WARN_WATERMARK) {
147 if (c->highest_inum >= INUM_WATERMARK) {
148 spin_unlock(&c->cnt_lock);
149 ubifs_err("out of inode numbers");
150 make_bad_inode(inode);
152 return ERR_PTR(-EINVAL);
154 ubifs_warn("running out of inode numbers (current %lu, max %d)",
155 (unsigned long)c->highest_inum, INUM_WATERMARK);
158 inode->i_ino = ++c->highest_inum;
160 * The creation sequence number remains with this inode for its
161 * lifetime. All nodes for this inode have a greater sequence number,
162 * and so it is possible to distinguish obsolete nodes belonging to a
163 * previous incarnation of the same inode number - for example, for the
164 * purpose of rebuilding the index.
166 ui->creat_sqnum = ++c->max_sqnum;
167 spin_unlock(&c->cnt_lock);
171 static int dbg_check_name(const struct ubifs_info *c,
172 const struct ubifs_dent_node *dent,
173 const struct qstr *nm)
175 if (!dbg_is_chk_gen(c))
177 if (le16_to_cpu(dent->nlen) != nm->len)
179 if (memcmp(dent->name, nm->name, nm->len))
184 static struct dentry *ubifs_lookup(struct inode *dir, struct dentry *dentry,
189 struct inode *inode = NULL;
190 struct ubifs_dent_node *dent;
191 struct ubifs_info *c = dir->i_sb->s_fs_info;
193 dbg_gen("'%pd' in dir ino %lu", dentry, dir->i_ino);
195 if (dentry->d_name.len > UBIFS_MAX_NLEN)
196 return ERR_PTR(-ENAMETOOLONG);
198 dent = kmalloc(UBIFS_MAX_DENT_NODE_SZ, GFP_NOFS);
200 return ERR_PTR(-ENOMEM);
202 dent_key_init(c, &key, dir->i_ino, &dentry->d_name);
204 err = ubifs_tnc_lookup_nm(c, &key, dent, &dentry->d_name);
206 if (err == -ENOENT) {
207 dbg_gen("not found");
213 if (dbg_check_name(c, dent, &dentry->d_name)) {
218 inode = ubifs_iget(dir->i_sb, le64_to_cpu(dent->inum));
221 * This should not happen. Probably the file-system needs
224 err = PTR_ERR(inode);
225 ubifs_err("dead directory entry '%pd', error %d",
227 ubifs_ro_mode(c, err);
234 * Note, d_splice_alias() would be required instead if we supported
237 d_add(dentry, inode);
245 static int ubifs_create(struct inode *dir, struct dentry *dentry, umode_t mode,
249 struct ubifs_info *c = dir->i_sb->s_fs_info;
250 int err, sz_change = CALC_DENT_SIZE(dentry->d_name.len);
251 struct ubifs_budget_req req = { .new_ino = 1, .new_dent = 1,
253 struct ubifs_inode *dir_ui = ubifs_inode(dir);
256 * Budget request settings: new inode, new direntry, changing the
257 * parent directory inode.
260 dbg_gen("dent '%pd', mode %#hx in dir ino %lu",
261 dentry, mode, dir->i_ino);
263 err = ubifs_budget_space(c, &req);
267 inode = ubifs_new_inode(c, dir, mode);
269 err = PTR_ERR(inode);
273 mutex_lock(&dir_ui->ui_mutex);
274 dir->i_size += sz_change;
275 dir_ui->ui_size = dir->i_size;
276 dir->i_mtime = dir->i_ctime = inode->i_ctime;
277 err = ubifs_jnl_update(c, dir, &dentry->d_name, inode, 0, 0);
280 mutex_unlock(&dir_ui->ui_mutex);
282 ubifs_release_budget(c, &req);
283 insert_inode_hash(inode);
284 d_instantiate(dentry, inode);
288 dir->i_size -= sz_change;
289 dir_ui->ui_size = dir->i_size;
290 mutex_unlock(&dir_ui->ui_mutex);
291 make_bad_inode(inode);
294 ubifs_release_budget(c, &req);
295 ubifs_err("cannot create regular file, error %d", err);
300 * vfs_dent_type - get VFS directory entry type.
301 * @type: UBIFS directory entry type
303 * This function converts UBIFS directory entry type into VFS directory entry
306 static unsigned int vfs_dent_type(uint8_t type)
309 case UBIFS_ITYPE_REG:
311 case UBIFS_ITYPE_DIR:
313 case UBIFS_ITYPE_LNK:
315 case UBIFS_ITYPE_BLK:
317 case UBIFS_ITYPE_CHR:
319 case UBIFS_ITYPE_FIFO:
321 case UBIFS_ITYPE_SOCK:
330 * The classical Unix view for directory is that it is a linear array of
331 * (name, inode number) entries. Linux/VFS assumes this model as well.
332 * Particularly, 'readdir()' call wants us to return a directory entry offset
333 * which later may be used to continue 'readdir()'ing the directory or to
334 * 'seek()' to that specific direntry. Obviously UBIFS does not really fit this
335 * model because directory entries are identified by keys, which may collide.
337 * UBIFS uses directory entry hash value for directory offsets, so
338 * 'seekdir()'/'telldir()' may not always work because of possible key
339 * collisions. But UBIFS guarantees that consecutive 'readdir()' calls work
340 * properly by means of saving full directory entry name in the private field
341 * of the file description object.
343 * This means that UBIFS cannot support NFS which requires full
344 * 'seekdir()'/'telldir()' support.
346 static int ubifs_readdir(struct file *file, struct dir_context *ctx)
351 struct ubifs_dent_node *dent;
352 struct inode *dir = file_inode(file);
353 struct ubifs_info *c = dir->i_sb->s_fs_info;
355 dbg_gen("dir ino %lu, f_pos %#llx", dir->i_ino, ctx->pos);
357 if (ctx->pos > UBIFS_S_KEY_HASH_MASK || ctx->pos == 2)
359 * The directory was seek'ed to a senseless position or there
360 * are no more entries.
364 if (file->f_version == 0) {
366 * The file was seek'ed, which means that @file->private_data
367 * is now invalid. This may also be just the first
368 * 'ubifs_readdir()' invocation, in which case
369 * @file->private_data is NULL, and the below code is
372 kfree(file->private_data);
373 file->private_data = NULL;
377 * 'generic_file_llseek()' unconditionally sets @file->f_version to
378 * zero, and we use this for detecting whether the file was seek'ed.
382 /* File positions 0 and 1 correspond to "." and ".." */
384 ubifs_assert(!file->private_data);
385 if (!dir_emit_dots(file, ctx))
388 /* Find the first entry in TNC and save it */
389 lowest_dent_key(c, &key, dir->i_ino);
391 dent = ubifs_tnc_next_ent(c, &key, &nm);
397 ctx->pos = key_hash_flash(c, &dent->key);
398 file->private_data = dent;
401 dent = file->private_data;
404 * The directory was seek'ed to and is now readdir'ed.
405 * Find the entry corresponding to @ctx->pos or the closest one.
407 dent_key_init_hash(c, &key, dir->i_ino, ctx->pos);
409 dent = ubifs_tnc_next_ent(c, &key, &nm);
414 ctx->pos = key_hash_flash(c, &dent->key);
415 file->private_data = dent;
419 dbg_gen("feed '%s', ino %llu, new f_pos %#x",
420 dent->name, (unsigned long long)le64_to_cpu(dent->inum),
421 key_hash_flash(c, &dent->key));
422 ubifs_assert(le64_to_cpu(dent->ch.sqnum) >
423 ubifs_inode(dir)->creat_sqnum);
425 nm.len = le16_to_cpu(dent->nlen);
426 if (!dir_emit(ctx, dent->name, nm.len,
427 le64_to_cpu(dent->inum),
428 vfs_dent_type(dent->type)))
431 /* Switch to the next entry */
432 key_read(c, &dent->key, &key);
433 nm.name = dent->name;
434 dent = ubifs_tnc_next_ent(c, &key, &nm);
440 kfree(file->private_data);
441 ctx->pos = key_hash_flash(c, &dent->key);
442 file->private_data = dent;
447 if (err != -ENOENT) {
448 ubifs_err("cannot find next direntry, error %d", err);
452 kfree(file->private_data);
453 file->private_data = NULL;
454 /* 2 is a special value indicating that there are no more direntries */
459 /* Free saved readdir() state when the directory is closed */
460 static int ubifs_dir_release(struct inode *dir, struct file *file)
462 kfree(file->private_data);
463 file->private_data = NULL;
468 * lock_2_inodes - a wrapper for locking two UBIFS inodes.
469 * @inode1: first inode
470 * @inode2: second inode
472 * We do not implement any tricks to guarantee strict lock ordering, because
473 * VFS has already done it for us on the @i_mutex. So this is just a simple
476 static void lock_2_inodes(struct inode *inode1, struct inode *inode2)
478 mutex_lock_nested(&ubifs_inode(inode1)->ui_mutex, WB_MUTEX_1);
479 mutex_lock_nested(&ubifs_inode(inode2)->ui_mutex, WB_MUTEX_2);
483 * unlock_2_inodes - a wrapper for unlocking two UBIFS inodes.
484 * @inode1: first inode
485 * @inode2: second inode
487 static void unlock_2_inodes(struct inode *inode1, struct inode *inode2)
489 mutex_unlock(&ubifs_inode(inode2)->ui_mutex);
490 mutex_unlock(&ubifs_inode(inode1)->ui_mutex);
493 static int ubifs_link(struct dentry *old_dentry, struct inode *dir,
494 struct dentry *dentry)
496 struct ubifs_info *c = dir->i_sb->s_fs_info;
497 struct inode *inode = old_dentry->d_inode;
498 struct ubifs_inode *ui = ubifs_inode(inode);
499 struct ubifs_inode *dir_ui = ubifs_inode(dir);
500 int err, sz_change = CALC_DENT_SIZE(dentry->d_name.len);
501 struct ubifs_budget_req req = { .new_dent = 1, .dirtied_ino = 2,
502 .dirtied_ino_d = ALIGN(ui->data_len, 8) };
505 * Budget request settings: new direntry, changing the target inode,
506 * changing the parent inode.
509 dbg_gen("dent '%pd' to ino %lu (nlink %d) in dir ino %lu",
510 dentry, inode->i_ino,
511 inode->i_nlink, dir->i_ino);
512 ubifs_assert(mutex_is_locked(&dir->i_mutex));
513 ubifs_assert(mutex_is_locked(&inode->i_mutex));
515 err = dbg_check_synced_i_size(c, inode);
519 err = ubifs_budget_space(c, &req);
523 lock_2_inodes(dir, inode);
526 inode->i_ctime = ubifs_current_time(inode);
527 dir->i_size += sz_change;
528 dir_ui->ui_size = dir->i_size;
529 dir->i_mtime = dir->i_ctime = inode->i_ctime;
530 err = ubifs_jnl_update(c, dir, &dentry->d_name, inode, 0, 0);
533 unlock_2_inodes(dir, inode);
535 ubifs_release_budget(c, &req);
536 d_instantiate(dentry, inode);
540 dir->i_size -= sz_change;
541 dir_ui->ui_size = dir->i_size;
543 unlock_2_inodes(dir, inode);
544 ubifs_release_budget(c, &req);
549 static int ubifs_unlink(struct inode *dir, struct dentry *dentry)
551 struct ubifs_info *c = dir->i_sb->s_fs_info;
552 struct inode *inode = dentry->d_inode;
553 struct ubifs_inode *dir_ui = ubifs_inode(dir);
554 int sz_change = CALC_DENT_SIZE(dentry->d_name.len);
555 int err, budgeted = 1;
556 struct ubifs_budget_req req = { .mod_dent = 1, .dirtied_ino = 2 };
557 unsigned int saved_nlink = inode->i_nlink;
560 * Budget request settings: deletion direntry, deletion inode (+1 for
561 * @dirtied_ino), changing the parent directory inode. If budgeting
562 * fails, go ahead anyway because we have extra space reserved for
566 dbg_gen("dent '%pd' from ino %lu (nlink %d) in dir ino %lu",
567 dentry, inode->i_ino,
568 inode->i_nlink, dir->i_ino);
569 ubifs_assert(mutex_is_locked(&dir->i_mutex));
570 ubifs_assert(mutex_is_locked(&inode->i_mutex));
571 err = dbg_check_synced_i_size(c, inode);
575 err = ubifs_budget_space(c, &req);
582 lock_2_inodes(dir, inode);
583 inode->i_ctime = ubifs_current_time(dir);
585 dir->i_size -= sz_change;
586 dir_ui->ui_size = dir->i_size;
587 dir->i_mtime = dir->i_ctime = inode->i_ctime;
588 err = ubifs_jnl_update(c, dir, &dentry->d_name, inode, 1, 0);
591 unlock_2_inodes(dir, inode);
594 ubifs_release_budget(c, &req);
596 /* We've deleted something - clean the "no space" flags */
597 c->bi.nospace = c->bi.nospace_rp = 0;
603 dir->i_size += sz_change;
604 dir_ui->ui_size = dir->i_size;
605 set_nlink(inode, saved_nlink);
606 unlock_2_inodes(dir, inode);
608 ubifs_release_budget(c, &req);
613 * check_dir_empty - check if a directory is empty or not.
614 * @c: UBIFS file-system description object
615 * @dir: VFS inode object of the directory to check
617 * This function checks if directory @dir is empty. Returns zero if the
618 * directory is empty, %-ENOTEMPTY if it is not, and other negative error codes
619 * in case of of errors.
621 static int check_dir_empty(struct ubifs_info *c, struct inode *dir)
623 struct qstr nm = { .name = NULL };
624 struct ubifs_dent_node *dent;
628 lowest_dent_key(c, &key, dir->i_ino);
629 dent = ubifs_tnc_next_ent(c, &key, &nm);
641 static int ubifs_rmdir(struct inode *dir, struct dentry *dentry)
643 struct ubifs_info *c = dir->i_sb->s_fs_info;
644 struct inode *inode = dentry->d_inode;
645 int sz_change = CALC_DENT_SIZE(dentry->d_name.len);
646 int err, budgeted = 1;
647 struct ubifs_inode *dir_ui = ubifs_inode(dir);
648 struct ubifs_budget_req req = { .mod_dent = 1, .dirtied_ino = 2 };
651 * Budget request settings: deletion direntry, deletion inode and
652 * changing the parent inode. If budgeting fails, go ahead anyway
653 * because we have extra space reserved for deletions.
656 dbg_gen("directory '%pd', ino %lu in dir ino %lu", dentry,
657 inode->i_ino, dir->i_ino);
658 ubifs_assert(mutex_is_locked(&dir->i_mutex));
659 ubifs_assert(mutex_is_locked(&inode->i_mutex));
660 err = check_dir_empty(c, dentry->d_inode);
664 err = ubifs_budget_space(c, &req);
671 lock_2_inodes(dir, inode);
672 inode->i_ctime = ubifs_current_time(dir);
675 dir->i_size -= sz_change;
676 dir_ui->ui_size = dir->i_size;
677 dir->i_mtime = dir->i_ctime = inode->i_ctime;
678 err = ubifs_jnl_update(c, dir, &dentry->d_name, inode, 1, 0);
681 unlock_2_inodes(dir, inode);
684 ubifs_release_budget(c, &req);
686 /* We've deleted something - clean the "no space" flags */
687 c->bi.nospace = c->bi.nospace_rp = 0;
693 dir->i_size += sz_change;
694 dir_ui->ui_size = dir->i_size;
697 unlock_2_inodes(dir, inode);
699 ubifs_release_budget(c, &req);
703 static int ubifs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
706 struct ubifs_inode *dir_ui = ubifs_inode(dir);
707 struct ubifs_info *c = dir->i_sb->s_fs_info;
708 int err, sz_change = CALC_DENT_SIZE(dentry->d_name.len);
709 struct ubifs_budget_req req = { .new_ino = 1, .new_dent = 1 };
712 * Budget request settings: new inode, new direntry and changing parent
716 dbg_gen("dent '%pd', mode %#hx in dir ino %lu",
717 dentry, mode, dir->i_ino);
719 err = ubifs_budget_space(c, &req);
723 inode = ubifs_new_inode(c, dir, S_IFDIR | mode);
725 err = PTR_ERR(inode);
729 mutex_lock(&dir_ui->ui_mutex);
730 insert_inode_hash(inode);
733 dir->i_size += sz_change;
734 dir_ui->ui_size = dir->i_size;
735 dir->i_mtime = dir->i_ctime = inode->i_ctime;
736 err = ubifs_jnl_update(c, dir, &dentry->d_name, inode, 0, 0);
738 ubifs_err("cannot create directory, error %d", err);
741 mutex_unlock(&dir_ui->ui_mutex);
743 ubifs_release_budget(c, &req);
744 d_instantiate(dentry, inode);
748 dir->i_size -= sz_change;
749 dir_ui->ui_size = dir->i_size;
751 mutex_unlock(&dir_ui->ui_mutex);
752 make_bad_inode(inode);
755 ubifs_release_budget(c, &req);
759 static int ubifs_mknod(struct inode *dir, struct dentry *dentry,
760 umode_t mode, dev_t rdev)
763 struct ubifs_inode *ui;
764 struct ubifs_inode *dir_ui = ubifs_inode(dir);
765 struct ubifs_info *c = dir->i_sb->s_fs_info;
766 union ubifs_dev_desc *dev = NULL;
767 int sz_change = CALC_DENT_SIZE(dentry->d_name.len);
769 struct ubifs_budget_req req = { .new_ino = 1, .new_dent = 1,
770 .new_ino_d = ALIGN(devlen, 8),
774 * Budget request settings: new inode, new direntry and changing parent
778 dbg_gen("dent '%pd' in dir ino %lu", dentry, dir->i_ino);
780 if (!new_valid_dev(rdev))
783 if (S_ISBLK(mode) || S_ISCHR(mode)) {
784 dev = kmalloc(sizeof(union ubifs_dev_desc), GFP_NOFS);
787 devlen = ubifs_encode_dev(dev, rdev);
790 err = ubifs_budget_space(c, &req);
796 inode = ubifs_new_inode(c, dir, mode);
799 err = PTR_ERR(inode);
803 init_special_inode(inode, inode->i_mode, rdev);
804 inode->i_size = ubifs_inode(inode)->ui_size = devlen;
805 ui = ubifs_inode(inode);
807 ui->data_len = devlen;
809 mutex_lock(&dir_ui->ui_mutex);
810 dir->i_size += sz_change;
811 dir_ui->ui_size = dir->i_size;
812 dir->i_mtime = dir->i_ctime = inode->i_ctime;
813 err = ubifs_jnl_update(c, dir, &dentry->d_name, inode, 0, 0);
816 mutex_unlock(&dir_ui->ui_mutex);
818 ubifs_release_budget(c, &req);
819 insert_inode_hash(inode);
820 d_instantiate(dentry, inode);
824 dir->i_size -= sz_change;
825 dir_ui->ui_size = dir->i_size;
826 mutex_unlock(&dir_ui->ui_mutex);
827 make_bad_inode(inode);
830 ubifs_release_budget(c, &req);
834 static int ubifs_symlink(struct inode *dir, struct dentry *dentry,
838 struct ubifs_inode *ui;
839 struct ubifs_inode *dir_ui = ubifs_inode(dir);
840 struct ubifs_info *c = dir->i_sb->s_fs_info;
841 int err, len = strlen(symname);
842 int sz_change = CALC_DENT_SIZE(dentry->d_name.len);
843 struct ubifs_budget_req req = { .new_ino = 1, .new_dent = 1,
844 .new_ino_d = ALIGN(len, 8),
848 * Budget request settings: new inode, new direntry and changing parent
852 dbg_gen("dent '%pd', target '%s' in dir ino %lu", dentry,
853 symname, dir->i_ino);
855 if (len > UBIFS_MAX_INO_DATA)
856 return -ENAMETOOLONG;
858 err = ubifs_budget_space(c, &req);
862 inode = ubifs_new_inode(c, dir, S_IFLNK | S_IRWXUGO);
864 err = PTR_ERR(inode);
868 ui = ubifs_inode(inode);
869 ui->data = kmalloc(len + 1, GFP_NOFS);
875 memcpy(ui->data, symname, len);
876 ((char *)ui->data)[len] = '\0';
878 * The terminating zero byte is not written to the flash media and it
879 * is put just to make later in-memory string processing simpler. Thus,
880 * data length is @len, not @len + %1.
883 inode->i_size = ubifs_inode(inode)->ui_size = len;
885 mutex_lock(&dir_ui->ui_mutex);
886 dir->i_size += sz_change;
887 dir_ui->ui_size = dir->i_size;
888 dir->i_mtime = dir->i_ctime = inode->i_ctime;
889 err = ubifs_jnl_update(c, dir, &dentry->d_name, inode, 0, 0);
892 mutex_unlock(&dir_ui->ui_mutex);
894 ubifs_release_budget(c, &req);
895 insert_inode_hash(inode);
896 d_instantiate(dentry, inode);
900 dir->i_size -= sz_change;
901 dir_ui->ui_size = dir->i_size;
902 mutex_unlock(&dir_ui->ui_mutex);
904 make_bad_inode(inode);
907 ubifs_release_budget(c, &req);
912 * lock_3_inodes - a wrapper for locking three UBIFS inodes.
913 * @inode1: first inode
914 * @inode2: second inode
915 * @inode3: third inode
917 * This function is used for 'ubifs_rename()' and @inode1 may be the same as
918 * @inode2 whereas @inode3 may be %NULL.
920 * We do not implement any tricks to guarantee strict lock ordering, because
921 * VFS has already done it for us on the @i_mutex. So this is just a simple
924 static void lock_3_inodes(struct inode *inode1, struct inode *inode2,
925 struct inode *inode3)
927 mutex_lock_nested(&ubifs_inode(inode1)->ui_mutex, WB_MUTEX_1);
928 if (inode2 != inode1)
929 mutex_lock_nested(&ubifs_inode(inode2)->ui_mutex, WB_MUTEX_2);
931 mutex_lock_nested(&ubifs_inode(inode3)->ui_mutex, WB_MUTEX_3);
935 * unlock_3_inodes - a wrapper for unlocking three UBIFS inodes for rename.
936 * @inode1: first inode
937 * @inode2: second inode
938 * @inode3: third inode
940 static void unlock_3_inodes(struct inode *inode1, struct inode *inode2,
941 struct inode *inode3)
944 mutex_unlock(&ubifs_inode(inode3)->ui_mutex);
945 if (inode1 != inode2)
946 mutex_unlock(&ubifs_inode(inode2)->ui_mutex);
947 mutex_unlock(&ubifs_inode(inode1)->ui_mutex);
950 static int ubifs_rename(struct inode *old_dir, struct dentry *old_dentry,
951 struct inode *new_dir, struct dentry *new_dentry)
953 struct ubifs_info *c = old_dir->i_sb->s_fs_info;
954 struct inode *old_inode = old_dentry->d_inode;
955 struct inode *new_inode = new_dentry->d_inode;
956 struct ubifs_inode *old_inode_ui = ubifs_inode(old_inode);
957 int err, release, sync = 0, move = (new_dir != old_dir);
958 int is_dir = S_ISDIR(old_inode->i_mode);
959 int unlink = !!new_inode;
960 int new_sz = CALC_DENT_SIZE(new_dentry->d_name.len);
961 int old_sz = CALC_DENT_SIZE(old_dentry->d_name.len);
962 struct ubifs_budget_req req = { .new_dent = 1, .mod_dent = 1,
964 struct ubifs_budget_req ino_req = { .dirtied_ino = 1,
965 .dirtied_ino_d = ALIGN(old_inode_ui->data_len, 8) };
966 struct timespec time;
967 unsigned int uninitialized_var(saved_nlink);
970 * Budget request settings: deletion direntry, new direntry, removing
971 * the old inode, and changing old and new parent directory inodes.
973 * However, this operation also marks the target inode as dirty and
974 * does not write it, so we allocate budget for the target inode
978 dbg_gen("dent '%pd' ino %lu in dir ino %lu to dent '%pd' in dir ino %lu",
979 old_dentry, old_inode->i_ino, old_dir->i_ino,
980 new_dentry, new_dir->i_ino);
981 ubifs_assert(mutex_is_locked(&old_dir->i_mutex));
982 ubifs_assert(mutex_is_locked(&new_dir->i_mutex));
984 ubifs_assert(mutex_is_locked(&new_inode->i_mutex));
987 if (unlink && is_dir) {
988 err = check_dir_empty(c, new_inode);
993 err = ubifs_budget_space(c, &req);
996 err = ubifs_budget_space(c, &ino_req);
998 ubifs_release_budget(c, &req);
1002 lock_3_inodes(old_dir, new_dir, new_inode);
1005 * Like most other Unix systems, set the @i_ctime for inodes on a
1008 time = ubifs_current_time(old_dir);
1009 old_inode->i_ctime = time;
1011 /* We must adjust parent link count when renaming directories */
1015 * @old_dir loses a link because we are moving
1016 * @old_inode to a different directory.
1018 drop_nlink(old_dir);
1020 * @new_dir only gains a link if we are not also
1021 * overwriting an existing directory.
1027 * @old_inode is not moving to a different directory,
1028 * but @old_dir still loses a link if we are
1029 * overwriting an existing directory.
1032 drop_nlink(old_dir);
1036 old_dir->i_size -= old_sz;
1037 ubifs_inode(old_dir)->ui_size = old_dir->i_size;
1038 old_dir->i_mtime = old_dir->i_ctime = time;
1039 new_dir->i_mtime = new_dir->i_ctime = time;
1042 * And finally, if we unlinked a direntry which happened to have the
1043 * same name as the moved direntry, we have to decrement @i_nlink of
1044 * the unlinked inode and change its ctime.
1048 * Directories cannot have hard-links, so if this is a
1049 * directory, just clear @i_nlink.
1051 saved_nlink = new_inode->i_nlink;
1053 clear_nlink(new_inode);
1055 drop_nlink(new_inode);
1056 new_inode->i_ctime = time;
1058 new_dir->i_size += new_sz;
1059 ubifs_inode(new_dir)->ui_size = new_dir->i_size;
1063 * Do not ask 'ubifs_jnl_rename()' to flush write-buffer if @old_inode
1064 * is dirty, because this will be done later on at the end of
1067 if (IS_SYNC(old_inode)) {
1068 sync = IS_DIRSYNC(old_dir) || IS_DIRSYNC(new_dir);
1069 if (unlink && IS_SYNC(new_inode))
1072 err = ubifs_jnl_rename(c, old_dir, old_dentry, new_dir, new_dentry,
1077 unlock_3_inodes(old_dir, new_dir, new_inode);
1078 ubifs_release_budget(c, &req);
1080 mutex_lock(&old_inode_ui->ui_mutex);
1081 release = old_inode_ui->dirty;
1082 mark_inode_dirty_sync(old_inode);
1083 mutex_unlock(&old_inode_ui->ui_mutex);
1086 ubifs_release_budget(c, &ino_req);
1087 if (IS_SYNC(old_inode))
1088 err = old_inode->i_sb->s_op->write_inode(old_inode, NULL);
1093 set_nlink(new_inode, saved_nlink);
1095 new_dir->i_size -= new_sz;
1096 ubifs_inode(new_dir)->ui_size = new_dir->i_size;
1098 old_dir->i_size += old_sz;
1099 ubifs_inode(old_dir)->ui_size = old_dir->i_size;
1104 drop_nlink(new_dir);
1110 unlock_3_inodes(old_dir, new_dir, new_inode);
1111 ubifs_release_budget(c, &ino_req);
1112 ubifs_release_budget(c, &req);
1116 int ubifs_getattr(struct vfsmount *mnt, struct dentry *dentry,
1120 struct inode *inode = dentry->d_inode;
1121 struct ubifs_inode *ui = ubifs_inode(inode);
1123 mutex_lock(&ui->ui_mutex);
1124 generic_fillattr(inode, stat);
1125 stat->blksize = UBIFS_BLOCK_SIZE;
1126 stat->size = ui->ui_size;
1129 * Unfortunately, the 'stat()' system call was designed for block
1130 * device based file systems, and it is not appropriate for UBIFS,
1131 * because UBIFS does not have notion of "block". For example, it is
1132 * difficult to tell how many block a directory takes - it actually
1133 * takes less than 300 bytes, but we have to round it to block size,
1134 * which introduces large mistake. This makes utilities like 'du' to
1135 * report completely senseless numbers. This is the reason why UBIFS
1136 * goes the same way as JFFS2 - it reports zero blocks for everything
1137 * but regular files, which makes more sense than reporting completely
1140 if (S_ISREG(inode->i_mode)) {
1141 size = ui->xattr_size;
1143 size = ALIGN(size, UBIFS_BLOCK_SIZE);
1145 * Note, user-space expects 512-byte blocks count irrespectively
1146 * of what was reported in @stat->size.
1148 stat->blocks = size >> 9;
1151 mutex_unlock(&ui->ui_mutex);
1155 const struct inode_operations ubifs_dir_inode_operations = {
1156 .lookup = ubifs_lookup,
1157 .create = ubifs_create,
1159 .symlink = ubifs_symlink,
1160 .unlink = ubifs_unlink,
1161 .mkdir = ubifs_mkdir,
1162 .rmdir = ubifs_rmdir,
1163 .mknod = ubifs_mknod,
1164 .rename = ubifs_rename,
1165 .setattr = ubifs_setattr,
1166 .getattr = ubifs_getattr,
1167 .setxattr = ubifs_setxattr,
1168 .getxattr = ubifs_getxattr,
1169 .listxattr = ubifs_listxattr,
1170 .removexattr = ubifs_removexattr,
1173 const struct file_operations ubifs_dir_operations = {
1174 .llseek = generic_file_llseek,
1175 .release = ubifs_dir_release,
1176 .read = generic_read_dir,
1177 .iterate = ubifs_readdir,
1178 .fsync = ubifs_fsync,
1179 .unlocked_ioctl = ubifs_ioctl,
1180 #ifdef CONFIG_COMPAT
1181 .compat_ioctl = ubifs_compat_ioctl,