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(c, "out of inode numbers");
150 make_bad_inode(inode);
152 return ERR_PTR(-EINVAL);
154 ubifs_warn(c, "running out of inode numbers (current %lu, max %u)",
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(c, "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 err = ubifs_init_security(dir, inode, &dentry->d_name);
277 mutex_lock(&dir_ui->ui_mutex);
278 dir->i_size += sz_change;
279 dir_ui->ui_size = dir->i_size;
280 dir->i_mtime = dir->i_ctime = inode->i_ctime;
281 err = ubifs_jnl_update(c, dir, &dentry->d_name, inode, 0, 0);
284 mutex_unlock(&dir_ui->ui_mutex);
286 ubifs_release_budget(c, &req);
287 insert_inode_hash(inode);
288 d_instantiate(dentry, inode);
292 dir->i_size -= sz_change;
293 dir_ui->ui_size = dir->i_size;
294 mutex_unlock(&dir_ui->ui_mutex);
296 make_bad_inode(inode);
299 ubifs_release_budget(c, &req);
300 ubifs_err(c, "cannot create regular file, error %d", err);
304 static int do_tmpfile(struct inode *dir, struct dentry *dentry,
305 umode_t mode, struct inode **whiteout)
308 struct ubifs_info *c = dir->i_sb->s_fs_info;
309 struct ubifs_budget_req req = { .new_ino = 1, .new_dent = 1};
310 struct ubifs_budget_req ino_req = { .dirtied_ino = 1 };
311 struct ubifs_inode *ui, *dir_ui = ubifs_inode(dir);
312 int err, instantiated = 0;
315 * Budget request settings: new dirty inode, new direntry,
316 * budget for dirtied inode will be released via writeback.
319 dbg_gen("dent '%pd', mode %#hx in dir ino %lu",
320 dentry, mode, dir->i_ino);
322 err = ubifs_budget_space(c, &req);
326 err = ubifs_budget_space(c, &ino_req);
328 ubifs_release_budget(c, &req);
332 inode = ubifs_new_inode(c, dir, mode);
334 err = PTR_ERR(inode);
337 ui = ubifs_inode(inode);
340 init_special_inode(inode, inode->i_mode, WHITEOUT_DEV);
341 ubifs_assert(inode->i_op == &ubifs_file_inode_operations);
344 err = ubifs_init_security(dir, inode, &dentry->d_name);
348 mutex_lock(&ui->ui_mutex);
349 insert_inode_hash(inode);
352 mark_inode_dirty(inode);
356 d_tmpfile(dentry, inode);
358 ubifs_assert(ui->dirty);
361 mutex_unlock(&ui->ui_mutex);
363 mutex_lock(&dir_ui->ui_mutex);
364 err = ubifs_jnl_update(c, dir, &dentry->d_name, inode, 1, 0);
367 mutex_unlock(&dir_ui->ui_mutex);
369 ubifs_release_budget(c, &req);
374 mutex_unlock(&dir_ui->ui_mutex);
376 make_bad_inode(inode);
380 ubifs_release_budget(c, &req);
382 ubifs_release_budget(c, &ino_req);
383 ubifs_err(c, "cannot create temporary file, error %d", err);
387 static int ubifs_tmpfile(struct inode *dir, struct dentry *dentry,
390 return do_tmpfile(dir, dentry, mode, NULL);
394 * vfs_dent_type - get VFS directory entry type.
395 * @type: UBIFS directory entry type
397 * This function converts UBIFS directory entry type into VFS directory entry
400 static unsigned int vfs_dent_type(uint8_t type)
403 case UBIFS_ITYPE_REG:
405 case UBIFS_ITYPE_DIR:
407 case UBIFS_ITYPE_LNK:
409 case UBIFS_ITYPE_BLK:
411 case UBIFS_ITYPE_CHR:
413 case UBIFS_ITYPE_FIFO:
415 case UBIFS_ITYPE_SOCK:
424 * The classical Unix view for directory is that it is a linear array of
425 * (name, inode number) entries. Linux/VFS assumes this model as well.
426 * Particularly, 'readdir()' call wants us to return a directory entry offset
427 * which later may be used to continue 'readdir()'ing the directory or to
428 * 'seek()' to that specific direntry. Obviously UBIFS does not really fit this
429 * model because directory entries are identified by keys, which may collide.
431 * UBIFS uses directory entry hash value for directory offsets, so
432 * 'seekdir()'/'telldir()' may not always work because of possible key
433 * collisions. But UBIFS guarantees that consecutive 'readdir()' calls work
434 * properly by means of saving full directory entry name in the private field
435 * of the file description object.
437 * This means that UBIFS cannot support NFS which requires full
438 * 'seekdir()'/'telldir()' support.
440 static int ubifs_readdir(struct file *file, struct dir_context *ctx)
445 struct ubifs_dent_node *dent;
446 struct inode *dir = file_inode(file);
447 struct ubifs_info *c = dir->i_sb->s_fs_info;
449 dbg_gen("dir ino %lu, f_pos %#llx", dir->i_ino, ctx->pos);
451 if (ctx->pos > UBIFS_S_KEY_HASH_MASK || ctx->pos == 2)
453 * The directory was seek'ed to a senseless position or there
454 * are no more entries.
458 if (file->f_version == 0) {
460 * The file was seek'ed, which means that @file->private_data
461 * is now invalid. This may also be just the first
462 * 'ubifs_readdir()' invocation, in which case
463 * @file->private_data is NULL, and the below code is
466 kfree(file->private_data);
467 file->private_data = NULL;
471 * 'generic_file_llseek()' unconditionally sets @file->f_version to
472 * zero, and we use this for detecting whether the file was seek'ed.
476 /* File positions 0 and 1 correspond to "." and ".." */
478 ubifs_assert(!file->private_data);
479 if (!dir_emit_dots(file, ctx))
482 /* Find the first entry in TNC and save it */
483 lowest_dent_key(c, &key, dir->i_ino);
485 dent = ubifs_tnc_next_ent(c, &key, &nm);
491 ctx->pos = key_hash_flash(c, &dent->key);
492 file->private_data = dent;
495 dent = file->private_data;
498 * The directory was seek'ed to and is now readdir'ed.
499 * Find the entry corresponding to @ctx->pos or the closest one.
501 dent_key_init_hash(c, &key, dir->i_ino, ctx->pos);
503 dent = ubifs_tnc_next_ent(c, &key, &nm);
508 ctx->pos = key_hash_flash(c, &dent->key);
509 file->private_data = dent;
513 dbg_gen("feed '%s', ino %llu, new f_pos %#x",
514 dent->name, (unsigned long long)le64_to_cpu(dent->inum),
515 key_hash_flash(c, &dent->key));
516 ubifs_assert(le64_to_cpu(dent->ch.sqnum) >
517 ubifs_inode(dir)->creat_sqnum);
519 nm.len = le16_to_cpu(dent->nlen);
520 if (!dir_emit(ctx, dent->name, nm.len,
521 le64_to_cpu(dent->inum),
522 vfs_dent_type(dent->type)))
525 /* Switch to the next entry */
526 key_read(c, &dent->key, &key);
527 nm.name = dent->name;
528 dent = ubifs_tnc_next_ent(c, &key, &nm);
534 kfree(file->private_data);
535 ctx->pos = key_hash_flash(c, &dent->key);
536 file->private_data = dent;
541 kfree(file->private_data);
542 file->private_data = NULL;
544 if (err != -ENOENT) {
545 ubifs_err(c, "cannot find next direntry, error %d", err);
549 /* 2 is a special value indicating that there are no more direntries */
554 /* Free saved readdir() state when the directory is closed */
555 static int ubifs_dir_release(struct inode *dir, struct file *file)
557 kfree(file->private_data);
558 file->private_data = NULL;
563 * lock_2_inodes - a wrapper for locking two UBIFS inodes.
564 * @inode1: first inode
565 * @inode2: second inode
567 * We do not implement any tricks to guarantee strict lock ordering, because
568 * VFS has already done it for us on the @i_mutex. So this is just a simple
571 static void lock_2_inodes(struct inode *inode1, struct inode *inode2)
573 mutex_lock_nested(&ubifs_inode(inode1)->ui_mutex, WB_MUTEX_1);
574 mutex_lock_nested(&ubifs_inode(inode2)->ui_mutex, WB_MUTEX_2);
578 * unlock_2_inodes - a wrapper for unlocking two UBIFS inodes.
579 * @inode1: first inode
580 * @inode2: second inode
582 static void unlock_2_inodes(struct inode *inode1, struct inode *inode2)
584 mutex_unlock(&ubifs_inode(inode2)->ui_mutex);
585 mutex_unlock(&ubifs_inode(inode1)->ui_mutex);
588 static int ubifs_link(struct dentry *old_dentry, struct inode *dir,
589 struct dentry *dentry)
591 struct ubifs_info *c = dir->i_sb->s_fs_info;
592 struct inode *inode = d_inode(old_dentry);
593 struct ubifs_inode *ui = ubifs_inode(inode);
594 struct ubifs_inode *dir_ui = ubifs_inode(dir);
595 int err, sz_change = CALC_DENT_SIZE(dentry->d_name.len);
596 struct ubifs_budget_req req = { .new_dent = 1, .dirtied_ino = 2,
597 .dirtied_ino_d = ALIGN(ui->data_len, 8) };
600 * Budget request settings: new direntry, changing the target inode,
601 * changing the parent inode.
604 dbg_gen("dent '%pd' to ino %lu (nlink %d) in dir ino %lu",
605 dentry, inode->i_ino,
606 inode->i_nlink, dir->i_ino);
607 ubifs_assert(inode_is_locked(dir));
608 ubifs_assert(inode_is_locked(inode));
610 err = dbg_check_synced_i_size(c, inode);
614 err = ubifs_budget_space(c, &req);
618 lock_2_inodes(dir, inode);
621 inode->i_ctime = ubifs_current_time(inode);
622 dir->i_size += sz_change;
623 dir_ui->ui_size = dir->i_size;
624 dir->i_mtime = dir->i_ctime = inode->i_ctime;
625 err = ubifs_jnl_update(c, dir, &dentry->d_name, inode, 0, 0);
628 unlock_2_inodes(dir, inode);
630 ubifs_release_budget(c, &req);
631 d_instantiate(dentry, inode);
635 dir->i_size -= sz_change;
636 dir_ui->ui_size = dir->i_size;
638 unlock_2_inodes(dir, inode);
639 ubifs_release_budget(c, &req);
644 static int ubifs_unlink(struct inode *dir, struct dentry *dentry)
646 struct ubifs_info *c = dir->i_sb->s_fs_info;
647 struct inode *inode = d_inode(dentry);
648 struct ubifs_inode *dir_ui = ubifs_inode(dir);
649 int sz_change = CALC_DENT_SIZE(dentry->d_name.len);
650 int err, budgeted = 1;
651 struct ubifs_budget_req req = { .mod_dent = 1, .dirtied_ino = 2 };
652 unsigned int saved_nlink = inode->i_nlink;
655 * Budget request settings: deletion direntry, deletion inode (+1 for
656 * @dirtied_ino), changing the parent directory inode. If budgeting
657 * fails, go ahead anyway because we have extra space reserved for
661 dbg_gen("dent '%pd' from ino %lu (nlink %d) in dir ino %lu",
662 dentry, inode->i_ino,
663 inode->i_nlink, dir->i_ino);
664 ubifs_assert(inode_is_locked(dir));
665 ubifs_assert(inode_is_locked(inode));
666 err = dbg_check_synced_i_size(c, inode);
670 err = ubifs_budget_space(c, &req);
677 lock_2_inodes(dir, inode);
678 inode->i_ctime = ubifs_current_time(dir);
680 dir->i_size -= sz_change;
681 dir_ui->ui_size = dir->i_size;
682 dir->i_mtime = dir->i_ctime = inode->i_ctime;
683 err = ubifs_jnl_update(c, dir, &dentry->d_name, inode, 1, 0);
686 unlock_2_inodes(dir, inode);
689 ubifs_release_budget(c, &req);
691 /* We've deleted something - clean the "no space" flags */
692 c->bi.nospace = c->bi.nospace_rp = 0;
698 dir->i_size += sz_change;
699 dir_ui->ui_size = dir->i_size;
700 set_nlink(inode, saved_nlink);
701 unlock_2_inodes(dir, inode);
703 ubifs_release_budget(c, &req);
708 * check_dir_empty - check if a directory is empty or not.
709 * @c: UBIFS file-system description object
710 * @dir: VFS inode object of the directory to check
712 * This function checks if directory @dir is empty. Returns zero if the
713 * directory is empty, %-ENOTEMPTY if it is not, and other negative error codes
714 * in case of of errors.
716 static int check_dir_empty(struct ubifs_info *c, struct inode *dir)
718 struct qstr nm = { .name = NULL };
719 struct ubifs_dent_node *dent;
723 lowest_dent_key(c, &key, dir->i_ino);
724 dent = ubifs_tnc_next_ent(c, &key, &nm);
736 static int ubifs_rmdir(struct inode *dir, struct dentry *dentry)
738 struct ubifs_info *c = dir->i_sb->s_fs_info;
739 struct inode *inode = d_inode(dentry);
740 int sz_change = CALC_DENT_SIZE(dentry->d_name.len);
741 int err, budgeted = 1;
742 struct ubifs_inode *dir_ui = ubifs_inode(dir);
743 struct ubifs_budget_req req = { .mod_dent = 1, .dirtied_ino = 2 };
746 * Budget request settings: deletion direntry, deletion inode and
747 * changing the parent inode. If budgeting fails, go ahead anyway
748 * because we have extra space reserved for deletions.
751 dbg_gen("directory '%pd', ino %lu in dir ino %lu", dentry,
752 inode->i_ino, dir->i_ino);
753 ubifs_assert(inode_is_locked(dir));
754 ubifs_assert(inode_is_locked(inode));
755 err = check_dir_empty(c, d_inode(dentry));
759 err = ubifs_budget_space(c, &req);
766 lock_2_inodes(dir, inode);
767 inode->i_ctime = ubifs_current_time(dir);
770 dir->i_size -= sz_change;
771 dir_ui->ui_size = dir->i_size;
772 dir->i_mtime = dir->i_ctime = inode->i_ctime;
773 err = ubifs_jnl_update(c, dir, &dentry->d_name, inode, 1, 0);
776 unlock_2_inodes(dir, inode);
779 ubifs_release_budget(c, &req);
781 /* We've deleted something - clean the "no space" flags */
782 c->bi.nospace = c->bi.nospace_rp = 0;
788 dir->i_size += sz_change;
789 dir_ui->ui_size = dir->i_size;
792 unlock_2_inodes(dir, inode);
794 ubifs_release_budget(c, &req);
798 static int ubifs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
801 struct ubifs_inode *dir_ui = ubifs_inode(dir);
802 struct ubifs_info *c = dir->i_sb->s_fs_info;
803 int err, sz_change = CALC_DENT_SIZE(dentry->d_name.len);
804 struct ubifs_budget_req req = { .new_ino = 1, .new_dent = 1 };
807 * Budget request settings: new inode, new direntry and changing parent
811 dbg_gen("dent '%pd', mode %#hx in dir ino %lu",
812 dentry, mode, dir->i_ino);
814 err = ubifs_budget_space(c, &req);
818 inode = ubifs_new_inode(c, dir, S_IFDIR | mode);
820 err = PTR_ERR(inode);
824 err = ubifs_init_security(dir, inode, &dentry->d_name);
828 mutex_lock(&dir_ui->ui_mutex);
829 insert_inode_hash(inode);
832 dir->i_size += sz_change;
833 dir_ui->ui_size = dir->i_size;
834 dir->i_mtime = dir->i_ctime = inode->i_ctime;
835 err = ubifs_jnl_update(c, dir, &dentry->d_name, inode, 0, 0);
837 ubifs_err(c, "cannot create directory, error %d", err);
840 mutex_unlock(&dir_ui->ui_mutex);
842 ubifs_release_budget(c, &req);
843 d_instantiate(dentry, inode);
847 dir->i_size -= sz_change;
848 dir_ui->ui_size = dir->i_size;
850 mutex_unlock(&dir_ui->ui_mutex);
852 make_bad_inode(inode);
855 ubifs_release_budget(c, &req);
859 static int ubifs_mknod(struct inode *dir, struct dentry *dentry,
860 umode_t mode, dev_t rdev)
863 struct ubifs_inode *ui;
864 struct ubifs_inode *dir_ui = ubifs_inode(dir);
865 struct ubifs_info *c = dir->i_sb->s_fs_info;
866 union ubifs_dev_desc *dev = NULL;
867 int sz_change = CALC_DENT_SIZE(dentry->d_name.len);
869 struct ubifs_budget_req req = { .new_ino = 1, .new_dent = 1,
870 .new_ino_d = ALIGN(devlen, 8),
874 * Budget request settings: new inode, new direntry and changing parent
878 dbg_gen("dent '%pd' in dir ino %lu", dentry, dir->i_ino);
880 if (S_ISBLK(mode) || S_ISCHR(mode)) {
881 dev = kmalloc(sizeof(union ubifs_dev_desc), GFP_NOFS);
884 devlen = ubifs_encode_dev(dev, rdev);
887 err = ubifs_budget_space(c, &req);
893 inode = ubifs_new_inode(c, dir, mode);
896 err = PTR_ERR(inode);
900 init_special_inode(inode, inode->i_mode, rdev);
901 inode->i_size = ubifs_inode(inode)->ui_size = devlen;
902 ui = ubifs_inode(inode);
904 ui->data_len = devlen;
906 err = ubifs_init_security(dir, inode, &dentry->d_name);
910 mutex_lock(&dir_ui->ui_mutex);
911 dir->i_size += sz_change;
912 dir_ui->ui_size = dir->i_size;
913 dir->i_mtime = dir->i_ctime = inode->i_ctime;
914 err = ubifs_jnl_update(c, dir, &dentry->d_name, inode, 0, 0);
917 mutex_unlock(&dir_ui->ui_mutex);
919 ubifs_release_budget(c, &req);
920 insert_inode_hash(inode);
921 d_instantiate(dentry, inode);
925 dir->i_size -= sz_change;
926 dir_ui->ui_size = dir->i_size;
927 mutex_unlock(&dir_ui->ui_mutex);
929 make_bad_inode(inode);
932 ubifs_release_budget(c, &req);
936 static int ubifs_symlink(struct inode *dir, struct dentry *dentry,
940 struct ubifs_inode *ui;
941 struct ubifs_inode *dir_ui = ubifs_inode(dir);
942 struct ubifs_info *c = dir->i_sb->s_fs_info;
943 int err, len = strlen(symname);
944 int sz_change = CALC_DENT_SIZE(dentry->d_name.len);
945 struct ubifs_budget_req req = { .new_ino = 1, .new_dent = 1,
946 .new_ino_d = ALIGN(len, 8),
950 * Budget request settings: new inode, new direntry and changing parent
954 dbg_gen("dent '%pd', target '%s' in dir ino %lu", dentry,
955 symname, dir->i_ino);
957 if (len > UBIFS_MAX_INO_DATA)
958 return -ENAMETOOLONG;
960 err = ubifs_budget_space(c, &req);
964 inode = ubifs_new_inode(c, dir, S_IFLNK | S_IRWXUGO);
966 err = PTR_ERR(inode);
970 ui = ubifs_inode(inode);
971 ui->data = kmalloc(len + 1, GFP_NOFS);
977 memcpy(ui->data, symname, len);
978 ((char *)ui->data)[len] = '\0';
979 inode->i_link = ui->data;
981 * The terminating zero byte is not written to the flash media and it
982 * is put just to make later in-memory string processing simpler. Thus,
983 * data length is @len, not @len + %1.
986 inode->i_size = ubifs_inode(inode)->ui_size = len;
988 err = ubifs_init_security(dir, inode, &dentry->d_name);
992 mutex_lock(&dir_ui->ui_mutex);
993 dir->i_size += sz_change;
994 dir_ui->ui_size = dir->i_size;
995 dir->i_mtime = dir->i_ctime = inode->i_ctime;
996 err = ubifs_jnl_update(c, dir, &dentry->d_name, inode, 0, 0);
999 mutex_unlock(&dir_ui->ui_mutex);
1001 ubifs_release_budget(c, &req);
1002 insert_inode_hash(inode);
1003 d_instantiate(dentry, inode);
1007 dir->i_size -= sz_change;
1008 dir_ui->ui_size = dir->i_size;
1009 mutex_unlock(&dir_ui->ui_mutex);
1011 make_bad_inode(inode);
1014 ubifs_release_budget(c, &req);
1019 * lock_4_inodes - a wrapper for locking three UBIFS inodes.
1020 * @inode1: first inode
1021 * @inode2: second inode
1022 * @inode3: third inode
1023 * @inode4: fouth inode
1025 * This function is used for 'ubifs_rename()' and @inode1 may be the same as
1026 * @inode2 whereas @inode3 and @inode4 may be %NULL.
1028 * We do not implement any tricks to guarantee strict lock ordering, because
1029 * VFS has already done it for us on the @i_mutex. So this is just a simple
1032 static void lock_4_inodes(struct inode *inode1, struct inode *inode2,
1033 struct inode *inode3, struct inode *inode4)
1035 mutex_lock_nested(&ubifs_inode(inode1)->ui_mutex, WB_MUTEX_1);
1036 if (inode2 != inode1)
1037 mutex_lock_nested(&ubifs_inode(inode2)->ui_mutex, WB_MUTEX_2);
1039 mutex_lock_nested(&ubifs_inode(inode3)->ui_mutex, WB_MUTEX_3);
1041 mutex_lock_nested(&ubifs_inode(inode4)->ui_mutex, WB_MUTEX_4);
1045 * unlock_4_inodes - a wrapper for unlocking three UBIFS inodes for rename.
1046 * @inode1: first inode
1047 * @inode2: second inode
1048 * @inode3: third inode
1049 * @inode4: fouth inode
1051 static void unlock_4_inodes(struct inode *inode1, struct inode *inode2,
1052 struct inode *inode3, struct inode *inode4)
1055 mutex_unlock(&ubifs_inode(inode4)->ui_mutex);
1057 mutex_unlock(&ubifs_inode(inode3)->ui_mutex);
1058 if (inode1 != inode2)
1059 mutex_unlock(&ubifs_inode(inode2)->ui_mutex);
1060 mutex_unlock(&ubifs_inode(inode1)->ui_mutex);
1063 static int ubifs_rename(struct inode *old_dir, struct dentry *old_dentry,
1064 struct inode *new_dir, struct dentry *new_dentry,
1067 struct ubifs_info *c = old_dir->i_sb->s_fs_info;
1068 struct inode *old_inode = d_inode(old_dentry);
1069 struct inode *new_inode = d_inode(new_dentry);
1070 struct inode *whiteout = NULL;
1071 struct ubifs_inode *old_inode_ui = ubifs_inode(old_inode);
1072 struct ubifs_inode *whiteout_ui = NULL;
1073 int err, release, sync = 0, move = (new_dir != old_dir);
1074 int is_dir = S_ISDIR(old_inode->i_mode);
1075 int unlink = !!new_inode;
1076 int new_sz = CALC_DENT_SIZE(new_dentry->d_name.len);
1077 int old_sz = CALC_DENT_SIZE(old_dentry->d_name.len);
1078 struct ubifs_budget_req req = { .new_dent = 1, .mod_dent = 1,
1080 struct ubifs_budget_req ino_req = { .dirtied_ino = 1,
1081 .dirtied_ino_d = ALIGN(old_inode_ui->data_len, 8) };
1082 struct timespec time;
1083 unsigned int uninitialized_var(saved_nlink);
1085 if (flags & ~RENAME_NOREPLACE)
1089 * Budget request settings: deletion direntry, new direntry, removing
1090 * the old inode, and changing old and new parent directory inodes.
1092 * However, this operation also marks the target inode as dirty and
1093 * does not write it, so we allocate budget for the target inode
1097 dbg_gen("dent '%pd' ino %lu in dir ino %lu to dent '%pd' in dir ino %lu flags 0x%x",
1098 old_dentry, old_inode->i_ino, old_dir->i_ino,
1099 new_dentry, new_dir->i_ino, flags);
1102 ubifs_assert(inode_is_locked(new_inode));
1104 if (unlink && is_dir) {
1105 err = check_dir_empty(c, new_inode);
1110 err = ubifs_budget_space(c, &req);
1113 err = ubifs_budget_space(c, &ino_req);
1115 ubifs_release_budget(c, &req);
1119 if (flags & RENAME_WHITEOUT) {
1120 union ubifs_dev_desc *dev = NULL;
1122 dev = kmalloc(sizeof(union ubifs_dev_desc), GFP_NOFS);
1124 ubifs_release_budget(c, &req);
1125 ubifs_release_budget(c, &ino_req);
1129 err = do_tmpfile(old_dir, old_dentry, S_IFCHR | WHITEOUT_MODE, &whiteout);
1131 ubifs_release_budget(c, &req);
1132 ubifs_release_budget(c, &ino_req);
1137 whiteout->i_state |= I_LINKABLE;
1138 whiteout_ui = ubifs_inode(whiteout);
1139 whiteout_ui->data = dev;
1140 whiteout_ui->data_len = ubifs_encode_dev(dev, MKDEV(0, 0));
1141 ubifs_assert(!whiteout_ui->dirty);
1144 lock_4_inodes(old_dir, new_dir, new_inode, whiteout);
1147 * Like most other Unix systems, set the @i_ctime for inodes on a
1150 time = ubifs_current_time(old_dir);
1151 old_inode->i_ctime = time;
1153 /* We must adjust parent link count when renaming directories */
1157 * @old_dir loses a link because we are moving
1158 * @old_inode to a different directory.
1160 drop_nlink(old_dir);
1162 * @new_dir only gains a link if we are not also
1163 * overwriting an existing directory.
1169 * @old_inode is not moving to a different directory,
1170 * but @old_dir still loses a link if we are
1171 * overwriting an existing directory.
1174 drop_nlink(old_dir);
1178 old_dir->i_size -= old_sz;
1179 ubifs_inode(old_dir)->ui_size = old_dir->i_size;
1180 old_dir->i_mtime = old_dir->i_ctime = time;
1181 new_dir->i_mtime = new_dir->i_ctime = time;
1184 * And finally, if we unlinked a direntry which happened to have the
1185 * same name as the moved direntry, we have to decrement @i_nlink of
1186 * the unlinked inode and change its ctime.
1190 * Directories cannot have hard-links, so if this is a
1191 * directory, just clear @i_nlink.
1193 saved_nlink = new_inode->i_nlink;
1195 clear_nlink(new_inode);
1197 drop_nlink(new_inode);
1198 new_inode->i_ctime = time;
1200 new_dir->i_size += new_sz;
1201 ubifs_inode(new_dir)->ui_size = new_dir->i_size;
1205 * Do not ask 'ubifs_jnl_rename()' to flush write-buffer if @old_inode
1206 * is dirty, because this will be done later on at the end of
1209 if (IS_SYNC(old_inode)) {
1210 sync = IS_DIRSYNC(old_dir) || IS_DIRSYNC(new_dir);
1211 if (unlink && IS_SYNC(new_inode))
1216 struct ubifs_budget_req wht_req = { .dirtied_ino = 1,
1218 ALIGN(ubifs_inode(whiteout)->data_len, 8) };
1220 err = ubifs_budget_space(c, &wht_req);
1222 ubifs_release_budget(c, &req);
1223 ubifs_release_budget(c, &ino_req);
1224 kfree(whiteout_ui->data);
1225 whiteout_ui->data_len = 0;
1230 inc_nlink(whiteout);
1231 mark_inode_dirty(whiteout);
1232 whiteout->i_state &= ~I_LINKABLE;
1236 err = ubifs_jnl_rename(c, old_dir, old_dentry, new_dir, new_dentry, whiteout,
1241 unlock_4_inodes(old_dir, new_dir, new_inode, whiteout);
1242 ubifs_release_budget(c, &req);
1244 mutex_lock(&old_inode_ui->ui_mutex);
1245 release = old_inode_ui->dirty;
1246 mark_inode_dirty_sync(old_inode);
1247 mutex_unlock(&old_inode_ui->ui_mutex);
1250 ubifs_release_budget(c, &ino_req);
1251 if (IS_SYNC(old_inode))
1252 err = old_inode->i_sb->s_op->write_inode(old_inode, NULL);
1257 set_nlink(new_inode, saved_nlink);
1259 new_dir->i_size -= new_sz;
1260 ubifs_inode(new_dir)->ui_size = new_dir->i_size;
1262 old_dir->i_size += old_sz;
1263 ubifs_inode(old_dir)->ui_size = old_dir->i_size;
1268 drop_nlink(new_dir);
1275 drop_nlink(whiteout);
1278 unlock_4_inodes(old_dir, new_dir, new_inode, whiteout);
1279 ubifs_release_budget(c, &ino_req);
1280 ubifs_release_budget(c, &req);
1284 static int ubifs_xrename(struct inode *old_dir, struct dentry *old_dentry,
1285 struct inode *new_dir, struct dentry *new_dentry)
1287 struct ubifs_info *c = old_dir->i_sb->s_fs_info;
1288 struct ubifs_budget_req req = { .new_dent = 1, .mod_dent = 1,
1290 int sync = IS_DIRSYNC(old_dir) || IS_DIRSYNC(new_dir);
1291 struct inode *fst_inode = d_inode(old_dentry);
1292 struct inode *snd_inode = d_inode(new_dentry);
1293 struct timespec time;
1296 ubifs_assert(fst_inode && snd_inode);
1298 lock_4_inodes(old_dir, new_dir, NULL, NULL);
1300 time = ubifs_current_time(old_dir);
1301 fst_inode->i_ctime = time;
1302 snd_inode->i_ctime = time;
1303 old_dir->i_mtime = old_dir->i_ctime = time;
1304 new_dir->i_mtime = new_dir->i_ctime = time;
1306 if (old_dir != new_dir) {
1307 if (S_ISDIR(fst_inode->i_mode) && !S_ISDIR(snd_inode->i_mode)) {
1309 drop_nlink(old_dir);
1311 else if (!S_ISDIR(fst_inode->i_mode) && S_ISDIR(snd_inode->i_mode)) {
1312 drop_nlink(new_dir);
1317 err = ubifs_jnl_xrename(c, old_dir, old_dentry, new_dir, new_dentry,
1320 unlock_4_inodes(old_dir, new_dir, NULL, NULL);
1321 ubifs_release_budget(c, &req);
1326 static int ubifs_rename2(struct inode *old_dir, struct dentry *old_dentry,
1327 struct inode *new_dir, struct dentry *new_dentry,
1330 if (flags & ~(RENAME_NOREPLACE | RENAME_WHITEOUT | RENAME_EXCHANGE))
1333 ubifs_assert(inode_is_locked(old_dir));
1334 ubifs_assert(inode_is_locked(new_dir));
1336 if (flags & RENAME_EXCHANGE)
1337 return ubifs_xrename(old_dir, old_dentry, new_dir, new_dentry);
1339 return ubifs_rename(old_dir, old_dentry, new_dir, new_dentry, flags);
1342 int ubifs_getattr(struct vfsmount *mnt, struct dentry *dentry,
1346 struct inode *inode = d_inode(dentry);
1347 struct ubifs_inode *ui = ubifs_inode(inode);
1349 mutex_lock(&ui->ui_mutex);
1350 generic_fillattr(inode, stat);
1351 stat->blksize = UBIFS_BLOCK_SIZE;
1352 stat->size = ui->ui_size;
1355 * Unfortunately, the 'stat()' system call was designed for block
1356 * device based file systems, and it is not appropriate for UBIFS,
1357 * because UBIFS does not have notion of "block". For example, it is
1358 * difficult to tell how many block a directory takes - it actually
1359 * takes less than 300 bytes, but we have to round it to block size,
1360 * which introduces large mistake. This makes utilities like 'du' to
1361 * report completely senseless numbers. This is the reason why UBIFS
1362 * goes the same way as JFFS2 - it reports zero blocks for everything
1363 * but regular files, which makes more sense than reporting completely
1366 if (S_ISREG(inode->i_mode)) {
1367 size = ui->xattr_size;
1369 size = ALIGN(size, UBIFS_BLOCK_SIZE);
1371 * Note, user-space expects 512-byte blocks count irrespectively
1372 * of what was reported in @stat->size.
1374 stat->blocks = size >> 9;
1377 mutex_unlock(&ui->ui_mutex);
1381 const struct inode_operations ubifs_dir_inode_operations = {
1382 .lookup = ubifs_lookup,
1383 .create = ubifs_create,
1385 .symlink = ubifs_symlink,
1386 .unlink = ubifs_unlink,
1387 .mkdir = ubifs_mkdir,
1388 .rmdir = ubifs_rmdir,
1389 .mknod = ubifs_mknod,
1390 .rename = ubifs_rename2,
1391 .setattr = ubifs_setattr,
1392 .getattr = ubifs_getattr,
1393 .listxattr = ubifs_listxattr,
1394 #ifdef CONFIG_UBIFS_ATIME_SUPPORT
1395 .update_time = ubifs_update_time,
1397 .tmpfile = ubifs_tmpfile,
1400 const struct file_operations ubifs_dir_operations = {
1401 .llseek = generic_file_llseek,
1402 .release = ubifs_dir_release,
1403 .read = generic_read_dir,
1404 .iterate_shared = ubifs_readdir,
1405 .fsync = ubifs_fsync,
1406 .unlocked_ioctl = ubifs_ioctl,
1407 #ifdef CONFIG_COMPAT
1408 .compat_ioctl = ubifs_compat_ioctl,