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, int 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 #ifdef CONFIG_UBIFS_FS_DEBUG
175 static int dbg_check_name(struct ubifs_dent_node *dent, struct qstr *nm)
177 if (!(ubifs_chk_flags & UBIFS_CHK_GEN))
179 if (le16_to_cpu(dent->nlen) != nm->len)
181 if (memcmp(dent->name, nm->name, nm->len))
188 #define dbg_check_name(dent, nm) 0
192 static struct dentry *ubifs_lookup(struct inode *dir, struct dentry *dentry,
193 struct nameidata *nd)
197 struct inode *inode = NULL;
198 struct ubifs_dent_node *dent;
199 struct ubifs_info *c = dir->i_sb->s_fs_info;
201 dbg_gen("'%.*s' in dir ino %lu",
202 dentry->d_name.len, dentry->d_name.name, dir->i_ino);
204 if (dentry->d_name.len > UBIFS_MAX_NLEN)
205 return ERR_PTR(-ENAMETOOLONG);
207 dent = kmalloc(UBIFS_MAX_DENT_NODE_SZ, GFP_NOFS);
209 return ERR_PTR(-ENOMEM);
211 dent_key_init(c, &key, dir->i_ino, &dentry->d_name);
213 err = ubifs_tnc_lookup_nm(c, &key, dent, &dentry->d_name);
215 if (err == -ENOENT) {
216 dbg_gen("not found");
222 if (dbg_check_name(dent, &dentry->d_name)) {
227 inode = ubifs_iget(dir->i_sb, le64_to_cpu(dent->inum));
230 * This should not happen. Probably the file-system needs
233 err = PTR_ERR(inode);
234 ubifs_err("dead directory entry '%.*s', error %d",
235 dentry->d_name.len, dentry->d_name.name, err);
236 ubifs_ro_mode(c, err);
243 * Note, d_splice_alias() would be required instead if we supported
246 d_add(dentry, inode);
254 static int ubifs_create(struct inode *dir, struct dentry *dentry, int mode,
255 struct nameidata *nd)
258 struct ubifs_info *c = dir->i_sb->s_fs_info;
259 int err, sz_change = CALC_DENT_SIZE(dentry->d_name.len);
260 struct ubifs_budget_req req = { .new_ino = 1, .new_dent = 1,
262 struct ubifs_inode *dir_ui = ubifs_inode(dir);
265 * Budget request settings: new inode, new direntry, changing the
266 * parent directory inode.
269 dbg_gen("dent '%.*s', mode %#x in dir ino %lu",
270 dentry->d_name.len, dentry->d_name.name, mode, dir->i_ino);
272 err = ubifs_budget_space(c, &req);
276 inode = ubifs_new_inode(c, dir, mode);
278 err = PTR_ERR(inode);
282 mutex_lock(&dir_ui->ui_mutex);
283 dir->i_size += sz_change;
284 dir_ui->ui_size = dir->i_size;
285 dir->i_mtime = dir->i_ctime = inode->i_ctime;
286 err = ubifs_jnl_update(c, dir, &dentry->d_name, inode, 0, 0);
289 mutex_unlock(&dir_ui->ui_mutex);
291 ubifs_release_budget(c, &req);
292 insert_inode_hash(inode);
293 d_instantiate(dentry, inode);
297 dir->i_size -= sz_change;
298 dir_ui->ui_size = dir->i_size;
299 mutex_unlock(&dir_ui->ui_mutex);
300 make_bad_inode(inode);
303 ubifs_release_budget(c, &req);
304 ubifs_err("cannot create regular file, error %d", err);
309 * vfs_dent_type - get VFS directory entry type.
310 * @type: UBIFS directory entry type
312 * This function converts UBIFS directory entry type into VFS directory entry
315 static unsigned int vfs_dent_type(uint8_t type)
318 case UBIFS_ITYPE_REG:
320 case UBIFS_ITYPE_DIR:
322 case UBIFS_ITYPE_LNK:
324 case UBIFS_ITYPE_BLK:
326 case UBIFS_ITYPE_CHR:
328 case UBIFS_ITYPE_FIFO:
330 case UBIFS_ITYPE_SOCK:
339 * The classical Unix view for directory is that it is a linear array of
340 * (name, inode number) entries. Linux/VFS assumes this model as well.
341 * Particularly, 'readdir()' call wants us to return a directory entry offset
342 * which later may be used to continue 'readdir()'ing the directory or to
343 * 'seek()' to that specific direntry. Obviously UBIFS does not really fit this
344 * model because directory entries are identified by keys, which may collide.
346 * UBIFS uses directory entry hash value for directory offsets, so
347 * 'seekdir()'/'telldir()' may not always work because of possible key
348 * collisions. But UBIFS guarantees that consecutive 'readdir()' calls work
349 * properly by means of saving full directory entry name in the private field
350 * of the file description object.
352 * This means that UBIFS cannot support NFS which requires full
353 * 'seekdir()'/'telldir()' support.
355 static int ubifs_readdir(struct file *file, void *dirent, filldir_t filldir)
360 struct ubifs_dent_node *dent;
361 struct inode *dir = file->f_path.dentry->d_inode;
362 struct ubifs_info *c = dir->i_sb->s_fs_info;
364 dbg_gen("dir ino %lu, f_pos %#llx", dir->i_ino, file->f_pos);
366 if (file->f_pos > UBIFS_S_KEY_HASH_MASK || file->f_pos == 2)
368 * The directory was seek'ed to a senseless position or there
369 * are no more entries.
373 /* File positions 0 and 1 correspond to "." and ".." */
374 if (file->f_pos == 0) {
375 ubifs_assert(!file->private_data);
376 over = filldir(dirent, ".", 1, 0, dir->i_ino, DT_DIR);
382 if (file->f_pos == 1) {
383 ubifs_assert(!file->private_data);
384 over = filldir(dirent, "..", 2, 1,
385 parent_ino(file->f_path.dentry), DT_DIR);
389 /* Find the first entry in TNC and save it */
390 lowest_dent_key(c, &key, dir->i_ino);
392 dent = ubifs_tnc_next_ent(c, &key, &nm);
398 file->f_pos = key_hash_flash(c, &dent->key);
399 file->private_data = dent;
402 dent = file->private_data;
405 * The directory was seek'ed to and is now readdir'ed.
406 * Find the entry corresponding to @file->f_pos or the
409 dent_key_init_hash(c, &key, dir->i_ino, file->f_pos);
411 dent = ubifs_tnc_next_ent(c, &key, &nm);
416 file->f_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 over = filldir(dirent, dent->name, nm.len, file->f_pos,
429 le64_to_cpu(dent->inum),
430 vfs_dent_type(dent->type));
434 /* Switch to the next entry */
435 key_read(c, &dent->key, &key);
436 nm.name = dent->name;
437 dent = ubifs_tnc_next_ent(c, &key, &nm);
443 kfree(file->private_data);
444 file->f_pos = key_hash_flash(c, &dent->key);
445 file->private_data = dent;
450 if (err != -ENOENT) {
451 ubifs_err("cannot find next direntry, error %d", err);
455 kfree(file->private_data);
456 file->private_data = NULL;
461 /* If a directory is seeked, we have to free saved readdir() state */
462 static loff_t ubifs_dir_llseek(struct file *file, loff_t offset, int origin)
464 kfree(file->private_data);
465 file->private_data = NULL;
466 return generic_file_llseek(file, offset, origin);
469 /* Free saved readdir() state when the directory is closed */
470 static int ubifs_dir_release(struct inode *dir, struct file *file)
472 kfree(file->private_data);
473 file->private_data = NULL;
478 * lock_2_inodes - a wrapper for locking two UBIFS inodes.
479 * @inode1: first inode
480 * @inode2: second inode
482 * We do not implement any tricks to guarantee strict lock ordering, because
483 * VFS has already done it for us on the @i_mutex. So this is just a simple
486 static void lock_2_inodes(struct inode *inode1, struct inode *inode2)
488 mutex_lock_nested(&ubifs_inode(inode1)->ui_mutex, WB_MUTEX_1);
489 mutex_lock_nested(&ubifs_inode(inode2)->ui_mutex, WB_MUTEX_2);
493 * unlock_2_inodes - a wrapper for unlocking two UBIFS inodes.
494 * @inode1: first inode
495 * @inode2: second inode
497 static void unlock_2_inodes(struct inode *inode1, struct inode *inode2)
499 mutex_unlock(&ubifs_inode(inode2)->ui_mutex);
500 mutex_unlock(&ubifs_inode(inode1)->ui_mutex);
503 static int ubifs_link(struct dentry *old_dentry, struct inode *dir,
504 struct dentry *dentry)
506 struct ubifs_info *c = dir->i_sb->s_fs_info;
507 struct inode *inode = old_dentry->d_inode;
508 struct ubifs_inode *ui = ubifs_inode(inode);
509 struct ubifs_inode *dir_ui = ubifs_inode(dir);
510 int err, sz_change = CALC_DENT_SIZE(dentry->d_name.len);
511 struct ubifs_budget_req req = { .new_dent = 1, .dirtied_ino = 2,
512 .dirtied_ino_d = ALIGN(ui->data_len, 8) };
515 * Budget request settings: new direntry, changing the target inode,
516 * changing the parent inode.
519 dbg_gen("dent '%.*s' to ino %lu (nlink %d) in dir ino %lu",
520 dentry->d_name.len, dentry->d_name.name, inode->i_ino,
521 inode->i_nlink, dir->i_ino);
522 ubifs_assert(mutex_is_locked(&dir->i_mutex));
523 ubifs_assert(mutex_is_locked(&inode->i_mutex));
525 err = dbg_check_synced_i_size(inode);
529 err = ubifs_budget_space(c, &req);
533 lock_2_inodes(dir, inode);
536 inode->i_ctime = ubifs_current_time(inode);
537 dir->i_size += sz_change;
538 dir_ui->ui_size = dir->i_size;
539 dir->i_mtime = dir->i_ctime = inode->i_ctime;
540 err = ubifs_jnl_update(c, dir, &dentry->d_name, inode, 0, 0);
543 unlock_2_inodes(dir, inode);
545 ubifs_release_budget(c, &req);
546 d_instantiate(dentry, inode);
550 dir->i_size -= sz_change;
551 dir_ui->ui_size = dir->i_size;
553 unlock_2_inodes(dir, inode);
554 ubifs_release_budget(c, &req);
559 static int ubifs_unlink(struct inode *dir, struct dentry *dentry)
561 struct ubifs_info *c = dir->i_sb->s_fs_info;
562 struct inode *inode = dentry->d_inode;
563 struct ubifs_inode *dir_ui = ubifs_inode(dir);
564 int sz_change = CALC_DENT_SIZE(dentry->d_name.len);
565 int err, budgeted = 1;
566 struct ubifs_budget_req req = { .mod_dent = 1, .dirtied_ino = 2 };
569 * Budget request settings: deletion direntry, deletion inode (+1 for
570 * @dirtied_ino), changing the parent directory inode. If budgeting
571 * fails, go ahead anyway because we have extra space reserved for
575 dbg_gen("dent '%.*s' from ino %lu (nlink %d) in dir ino %lu",
576 dentry->d_name.len, dentry->d_name.name, inode->i_ino,
577 inode->i_nlink, dir->i_ino);
578 ubifs_assert(mutex_is_locked(&dir->i_mutex));
579 ubifs_assert(mutex_is_locked(&inode->i_mutex));
580 err = dbg_check_synced_i_size(inode);
584 err = ubifs_budget_space(c, &req);
591 lock_2_inodes(dir, inode);
592 inode->i_ctime = ubifs_current_time(dir);
594 dir->i_size -= sz_change;
595 dir_ui->ui_size = dir->i_size;
596 dir->i_mtime = dir->i_ctime = inode->i_ctime;
597 err = ubifs_jnl_update(c, dir, &dentry->d_name, inode, 1, 0);
600 unlock_2_inodes(dir, inode);
603 ubifs_release_budget(c, &req);
605 /* We've deleted something - clean the "no space" flags */
606 c->nospace = c->nospace_rp = 0;
612 dir->i_size += sz_change;
613 dir_ui->ui_size = dir->i_size;
615 unlock_2_inodes(dir, inode);
617 ubifs_release_budget(c, &req);
622 * check_dir_empty - check if a directory is empty or not.
623 * @c: UBIFS file-system description object
624 * @dir: VFS inode object of the directory to check
626 * This function checks if directory @dir is empty. Returns zero if the
627 * directory is empty, %-ENOTEMPTY if it is not, and other negative error codes
628 * in case of of errors.
630 static int check_dir_empty(struct ubifs_info *c, struct inode *dir)
632 struct qstr nm = { .name = NULL };
633 struct ubifs_dent_node *dent;
637 lowest_dent_key(c, &key, dir->i_ino);
638 dent = ubifs_tnc_next_ent(c, &key, &nm);
650 static int ubifs_rmdir(struct inode *dir, struct dentry *dentry)
652 struct ubifs_info *c = dir->i_sb->s_fs_info;
653 struct inode *inode = dentry->d_inode;
654 int sz_change = CALC_DENT_SIZE(dentry->d_name.len);
655 int err, budgeted = 1;
656 struct ubifs_inode *dir_ui = ubifs_inode(dir);
657 struct ubifs_budget_req req = { .mod_dent = 1, .dirtied_ino = 2 };
660 * Budget request settings: deletion direntry, deletion inode and
661 * changing the parent inode. If budgeting fails, go ahead anyway
662 * because we have extra space reserved for deletions.
665 dbg_gen("directory '%.*s', ino %lu in dir ino %lu", dentry->d_name.len,
666 dentry->d_name.name, inode->i_ino, dir->i_ino);
667 ubifs_assert(mutex_is_locked(&dir->i_mutex));
668 ubifs_assert(mutex_is_locked(&inode->i_mutex));
669 err = check_dir_empty(c, dentry->d_inode);
673 err = ubifs_budget_space(c, &req);
680 lock_2_inodes(dir, inode);
681 inode->i_ctime = ubifs_current_time(dir);
684 dir->i_size -= sz_change;
685 dir_ui->ui_size = dir->i_size;
686 dir->i_mtime = dir->i_ctime = inode->i_ctime;
687 err = ubifs_jnl_update(c, dir, &dentry->d_name, inode, 1, 0);
690 unlock_2_inodes(dir, inode);
693 ubifs_release_budget(c, &req);
695 /* We've deleted something - clean the "no space" flags */
696 c->nospace = c->nospace_rp = 0;
702 dir->i_size += sz_change;
703 dir_ui->ui_size = dir->i_size;
707 unlock_2_inodes(dir, inode);
709 ubifs_release_budget(c, &req);
713 static int ubifs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
716 struct ubifs_inode *dir_ui = ubifs_inode(dir);
717 struct ubifs_info *c = dir->i_sb->s_fs_info;
718 int err, sz_change = CALC_DENT_SIZE(dentry->d_name.len);
719 struct ubifs_budget_req req = { .new_ino = 1, .new_dent = 1 };
722 * Budget request settings: new inode, new direntry and changing parent
726 dbg_gen("dent '%.*s', mode %#x in dir ino %lu",
727 dentry->d_name.len, dentry->d_name.name, mode, dir->i_ino);
729 err = ubifs_budget_space(c, &req);
733 inode = ubifs_new_inode(c, dir, S_IFDIR | mode);
735 err = PTR_ERR(inode);
739 mutex_lock(&dir_ui->ui_mutex);
740 insert_inode_hash(inode);
743 dir->i_size += sz_change;
744 dir_ui->ui_size = dir->i_size;
745 dir->i_mtime = dir->i_ctime = inode->i_ctime;
746 err = ubifs_jnl_update(c, dir, &dentry->d_name, inode, 0, 0);
748 ubifs_err("cannot create directory, error %d", err);
751 mutex_unlock(&dir_ui->ui_mutex);
753 ubifs_release_budget(c, &req);
754 d_instantiate(dentry, inode);
758 dir->i_size -= sz_change;
759 dir_ui->ui_size = dir->i_size;
761 mutex_unlock(&dir_ui->ui_mutex);
762 make_bad_inode(inode);
765 ubifs_release_budget(c, &req);
769 static int ubifs_mknod(struct inode *dir, struct dentry *dentry,
770 int mode, dev_t rdev)
773 struct ubifs_inode *ui;
774 struct ubifs_inode *dir_ui = ubifs_inode(dir);
775 struct ubifs_info *c = dir->i_sb->s_fs_info;
776 union ubifs_dev_desc *dev = NULL;
777 int sz_change = CALC_DENT_SIZE(dentry->d_name.len);
779 struct ubifs_budget_req req = { .new_ino = 1, .new_dent = 1,
780 .new_ino_d = ALIGN(devlen, 8),
784 * Budget request settings: new inode, new direntry and changing parent
788 dbg_gen("dent '%.*s' in dir ino %lu",
789 dentry->d_name.len, dentry->d_name.name, dir->i_ino);
791 if (!new_valid_dev(rdev))
794 if (S_ISBLK(mode) || S_ISCHR(mode)) {
795 dev = kmalloc(sizeof(union ubifs_dev_desc), GFP_NOFS);
798 devlen = ubifs_encode_dev(dev, rdev);
801 err = ubifs_budget_space(c, &req);
807 inode = ubifs_new_inode(c, dir, mode);
810 err = PTR_ERR(inode);
814 init_special_inode(inode, inode->i_mode, rdev);
815 inode->i_size = ubifs_inode(inode)->ui_size = devlen;
816 ui = ubifs_inode(inode);
818 ui->data_len = devlen;
820 mutex_lock(&dir_ui->ui_mutex);
821 dir->i_size += sz_change;
822 dir_ui->ui_size = dir->i_size;
823 dir->i_mtime = dir->i_ctime = inode->i_ctime;
824 err = ubifs_jnl_update(c, dir, &dentry->d_name, inode, 0, 0);
827 mutex_unlock(&dir_ui->ui_mutex);
829 ubifs_release_budget(c, &req);
830 insert_inode_hash(inode);
831 d_instantiate(dentry, inode);
835 dir->i_size -= sz_change;
836 dir_ui->ui_size = dir->i_size;
837 mutex_unlock(&dir_ui->ui_mutex);
838 make_bad_inode(inode);
841 ubifs_release_budget(c, &req);
845 static int ubifs_symlink(struct inode *dir, struct dentry *dentry,
849 struct ubifs_inode *ui;
850 struct ubifs_inode *dir_ui = ubifs_inode(dir);
851 struct ubifs_info *c = dir->i_sb->s_fs_info;
852 int err, len = strlen(symname);
853 int sz_change = CALC_DENT_SIZE(dentry->d_name.len);
854 struct ubifs_budget_req req = { .new_ino = 1, .new_dent = 1,
855 .new_ino_d = ALIGN(len, 8),
859 * Budget request settings: new inode, new direntry and changing parent
863 dbg_gen("dent '%.*s', target '%s' in dir ino %lu", dentry->d_name.len,
864 dentry->d_name.name, symname, dir->i_ino);
866 if (len > UBIFS_MAX_INO_DATA)
867 return -ENAMETOOLONG;
869 err = ubifs_budget_space(c, &req);
873 inode = ubifs_new_inode(c, dir, S_IFLNK | S_IRWXUGO);
875 err = PTR_ERR(inode);
879 ui = ubifs_inode(inode);
880 ui->data = kmalloc(len + 1, GFP_NOFS);
886 memcpy(ui->data, symname, len);
887 ((char *)ui->data)[len] = '\0';
889 * The terminating zero byte is not written to the flash media and it
890 * is put just to make later in-memory string processing simpler. Thus,
891 * data length is @len, not @len + %1.
894 inode->i_size = ubifs_inode(inode)->ui_size = len;
896 mutex_lock(&dir_ui->ui_mutex);
897 dir->i_size += sz_change;
898 dir_ui->ui_size = dir->i_size;
899 dir->i_mtime = dir->i_ctime = inode->i_ctime;
900 err = ubifs_jnl_update(c, dir, &dentry->d_name, inode, 0, 0);
903 mutex_unlock(&dir_ui->ui_mutex);
905 ubifs_release_budget(c, &req);
906 insert_inode_hash(inode);
907 d_instantiate(dentry, inode);
911 dir->i_size -= sz_change;
912 dir_ui->ui_size = dir->i_size;
913 mutex_unlock(&dir_ui->ui_mutex);
915 make_bad_inode(inode);
918 ubifs_release_budget(c, &req);
923 * lock_3_inodes - a wrapper for locking three UBIFS inodes.
924 * @inode1: first inode
925 * @inode2: second inode
926 * @inode3: third inode
928 * This function is used for 'ubifs_rename()' and @inode1 may be the same as
929 * @inode2 whereas @inode3 may be %NULL.
931 * We do not implement any tricks to guarantee strict lock ordering, because
932 * VFS has already done it for us on the @i_mutex. So this is just a simple
935 static void lock_3_inodes(struct inode *inode1, struct inode *inode2,
936 struct inode *inode3)
938 mutex_lock_nested(&ubifs_inode(inode1)->ui_mutex, WB_MUTEX_1);
939 if (inode2 != inode1)
940 mutex_lock_nested(&ubifs_inode(inode2)->ui_mutex, WB_MUTEX_2);
942 mutex_lock_nested(&ubifs_inode(inode3)->ui_mutex, WB_MUTEX_3);
946 * unlock_3_inodes - a wrapper for unlocking three UBIFS inodes for rename.
947 * @inode1: first inode
948 * @inode2: second inode
949 * @inode3: third inode
951 static void unlock_3_inodes(struct inode *inode1, struct inode *inode2,
952 struct inode *inode3)
955 mutex_unlock(&ubifs_inode(inode3)->ui_mutex);
956 if (inode1 != inode2)
957 mutex_unlock(&ubifs_inode(inode2)->ui_mutex);
958 mutex_unlock(&ubifs_inode(inode1)->ui_mutex);
961 static int ubifs_rename(struct inode *old_dir, struct dentry *old_dentry,
962 struct inode *new_dir, struct dentry *new_dentry)
964 struct ubifs_info *c = old_dir->i_sb->s_fs_info;
965 struct inode *old_inode = old_dentry->d_inode;
966 struct inode *new_inode = new_dentry->d_inode;
967 struct ubifs_inode *old_inode_ui = ubifs_inode(old_inode);
968 int err, release, sync = 0, move = (new_dir != old_dir);
969 int is_dir = S_ISDIR(old_inode->i_mode);
970 int unlink = !!new_inode;
971 int new_sz = CALC_DENT_SIZE(new_dentry->d_name.len);
972 int old_sz = CALC_DENT_SIZE(old_dentry->d_name.len);
973 struct ubifs_budget_req req = { .new_dent = 1, .mod_dent = 1,
975 struct ubifs_budget_req ino_req = { .dirtied_ino = 1,
976 .dirtied_ino_d = ALIGN(old_inode_ui->data_len, 8) };
977 struct timespec time;
980 * Budget request settings: deletion direntry, new direntry, removing
981 * the old inode, and changing old and new parent directory inodes.
983 * However, this operation also marks the target inode as dirty and
984 * does not write it, so we allocate budget for the target inode
988 dbg_gen("dent '%.*s' ino %lu in dir ino %lu to dent '%.*s' in "
989 "dir ino %lu", old_dentry->d_name.len, old_dentry->d_name.name,
990 old_inode->i_ino, old_dir->i_ino, new_dentry->d_name.len,
991 new_dentry->d_name.name, new_dir->i_ino);
992 ubifs_assert(mutex_is_locked(&old_dir->i_mutex));
993 ubifs_assert(mutex_is_locked(&new_dir->i_mutex));
995 ubifs_assert(mutex_is_locked(&new_inode->i_mutex));
998 if (unlink && is_dir) {
999 err = check_dir_empty(c, new_inode);
1004 err = ubifs_budget_space(c, &req);
1007 err = ubifs_budget_space(c, &ino_req);
1009 ubifs_release_budget(c, &req);
1013 lock_3_inodes(old_dir, new_dir, new_inode);
1016 * Like most other Unix systems, set the @i_ctime for inodes on a
1019 time = ubifs_current_time(old_dir);
1020 old_inode->i_ctime = time;
1022 /* We must adjust parent link count when renaming directories */
1026 * @old_dir loses a link because we are moving
1027 * @old_inode to a different directory.
1029 drop_nlink(old_dir);
1031 * @new_dir only gains a link if we are not also
1032 * overwriting an existing directory.
1038 * @old_inode is not moving to a different directory,
1039 * but @old_dir still loses a link if we are
1040 * overwriting an existing directory.
1043 drop_nlink(old_dir);
1047 old_dir->i_size -= old_sz;
1048 ubifs_inode(old_dir)->ui_size = old_dir->i_size;
1049 old_dir->i_mtime = old_dir->i_ctime = time;
1050 new_dir->i_mtime = new_dir->i_ctime = time;
1053 * And finally, if we unlinked a direntry which happened to have the
1054 * same name as the moved direntry, we have to decrement @i_nlink of
1055 * the unlinked inode and change its ctime.
1059 * Directories cannot have hard-links, so if this is a
1060 * directory, decrement its @i_nlink twice because an empty
1061 * directory has @i_nlink 2.
1064 drop_nlink(new_inode);
1065 new_inode->i_ctime = time;
1066 drop_nlink(new_inode);
1068 new_dir->i_size += new_sz;
1069 ubifs_inode(new_dir)->ui_size = new_dir->i_size;
1073 * Do not ask 'ubifs_jnl_rename()' to flush write-buffer if @old_inode
1074 * is dirty, because this will be done later on at the end of
1077 if (IS_SYNC(old_inode)) {
1078 sync = IS_DIRSYNC(old_dir) || IS_DIRSYNC(new_dir);
1079 if (unlink && IS_SYNC(new_inode))
1082 err = ubifs_jnl_rename(c, old_dir, old_dentry, new_dir, new_dentry,
1087 unlock_3_inodes(old_dir, new_dir, new_inode);
1088 ubifs_release_budget(c, &req);
1090 mutex_lock(&old_inode_ui->ui_mutex);
1091 release = old_inode_ui->dirty;
1092 mark_inode_dirty_sync(old_inode);
1093 mutex_unlock(&old_inode_ui->ui_mutex);
1096 ubifs_release_budget(c, &ino_req);
1097 if (IS_SYNC(old_inode))
1098 err = old_inode->i_sb->s_op->write_inode(old_inode, NULL);
1104 inc_nlink(new_inode);
1105 inc_nlink(new_inode);
1107 new_dir->i_size -= new_sz;
1108 ubifs_inode(new_dir)->ui_size = new_dir->i_size;
1110 old_dir->i_size += old_sz;
1111 ubifs_inode(old_dir)->ui_size = old_dir->i_size;
1116 drop_nlink(new_dir);
1122 unlock_3_inodes(old_dir, new_dir, new_inode);
1123 ubifs_release_budget(c, &ino_req);
1124 ubifs_release_budget(c, &req);
1128 int ubifs_getattr(struct vfsmount *mnt, struct dentry *dentry,
1132 struct inode *inode = dentry->d_inode;
1133 struct ubifs_inode *ui = ubifs_inode(inode);
1135 mutex_lock(&ui->ui_mutex);
1136 stat->dev = inode->i_sb->s_dev;
1137 stat->ino = inode->i_ino;
1138 stat->mode = inode->i_mode;
1139 stat->nlink = inode->i_nlink;
1140 stat->uid = inode->i_uid;
1141 stat->gid = inode->i_gid;
1142 stat->rdev = inode->i_rdev;
1143 stat->atime = inode->i_atime;
1144 stat->mtime = inode->i_mtime;
1145 stat->ctime = inode->i_ctime;
1146 stat->blksize = UBIFS_BLOCK_SIZE;
1147 stat->size = ui->ui_size;
1150 * Unfortunately, the 'stat()' system call was designed for block
1151 * device based file systems, and it is not appropriate for UBIFS,
1152 * because UBIFS does not have notion of "block". For example, it is
1153 * difficult to tell how many block a directory takes - it actually
1154 * takes less than 300 bytes, but we have to round it to block size,
1155 * which introduces large mistake. This makes utilities like 'du' to
1156 * report completely senseless numbers. This is the reason why UBIFS
1157 * goes the same way as JFFS2 - it reports zero blocks for everything
1158 * but regular files, which makes more sense than reporting completely
1161 if (S_ISREG(inode->i_mode)) {
1162 size = ui->xattr_size;
1164 size = ALIGN(size, UBIFS_BLOCK_SIZE);
1166 * Note, user-space expects 512-byte blocks count irrespectively
1167 * of what was reported in @stat->size.
1169 stat->blocks = size >> 9;
1172 mutex_unlock(&ui->ui_mutex);
1176 const struct inode_operations ubifs_dir_inode_operations = {
1177 .lookup = ubifs_lookup,
1178 .create = ubifs_create,
1180 .symlink = ubifs_symlink,
1181 .unlink = ubifs_unlink,
1182 .mkdir = ubifs_mkdir,
1183 .rmdir = ubifs_rmdir,
1184 .mknod = ubifs_mknod,
1185 .rename = ubifs_rename,
1186 .setattr = ubifs_setattr,
1187 .getattr = ubifs_getattr,
1188 #ifdef CONFIG_UBIFS_FS_XATTR
1189 .setxattr = ubifs_setxattr,
1190 .getxattr = ubifs_getxattr,
1191 .listxattr = ubifs_listxattr,
1192 .removexattr = ubifs_removexattr,
1196 const struct file_operations ubifs_dir_operations = {
1197 .llseek = ubifs_dir_llseek,
1198 .release = ubifs_dir_release,
1199 .read = generic_read_dir,
1200 .readdir = ubifs_readdir,
1201 .fsync = ubifs_fsync,
1202 .unlocked_ioctl = ubifs_ioctl,
1203 #ifdef CONFIG_COMPAT
1204 .compat_ioctl = ubifs_compat_ioctl,