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;
545 ubifs_err(c, "cannot find next direntry, error %d", err);
548 * -ENOENT is a non-fatal error in this context, the TNC uses
549 * it to indicate that the cursor moved past the current directory
550 * and readdir() has to stop.
555 /* 2 is a special value indicating that there are no more direntries */
560 /* Free saved readdir() state when the directory is closed */
561 static int ubifs_dir_release(struct inode *dir, struct file *file)
563 kfree(file->private_data);
564 file->private_data = NULL;
569 * lock_2_inodes - a wrapper for locking two UBIFS inodes.
570 * @inode1: first inode
571 * @inode2: second inode
573 * We do not implement any tricks to guarantee strict lock ordering, because
574 * VFS has already done it for us on the @i_mutex. So this is just a simple
577 static void lock_2_inodes(struct inode *inode1, struct inode *inode2)
579 mutex_lock_nested(&ubifs_inode(inode1)->ui_mutex, WB_MUTEX_1);
580 mutex_lock_nested(&ubifs_inode(inode2)->ui_mutex, WB_MUTEX_2);
584 * unlock_2_inodes - a wrapper for unlocking two UBIFS inodes.
585 * @inode1: first inode
586 * @inode2: second inode
588 static void unlock_2_inodes(struct inode *inode1, struct inode *inode2)
590 mutex_unlock(&ubifs_inode(inode2)->ui_mutex);
591 mutex_unlock(&ubifs_inode(inode1)->ui_mutex);
594 static int ubifs_link(struct dentry *old_dentry, struct inode *dir,
595 struct dentry *dentry)
597 struct ubifs_info *c = dir->i_sb->s_fs_info;
598 struct inode *inode = d_inode(old_dentry);
599 struct ubifs_inode *ui = ubifs_inode(inode);
600 struct ubifs_inode *dir_ui = ubifs_inode(dir);
601 int err, sz_change = CALC_DENT_SIZE(dentry->d_name.len);
602 struct ubifs_budget_req req = { .new_dent = 1, .dirtied_ino = 2,
603 .dirtied_ino_d = ALIGN(ui->data_len, 8) };
606 * Budget request settings: new direntry, changing the target inode,
607 * changing the parent inode.
610 dbg_gen("dent '%pd' to ino %lu (nlink %d) in dir ino %lu",
611 dentry, inode->i_ino,
612 inode->i_nlink, dir->i_ino);
613 ubifs_assert(inode_is_locked(dir));
614 ubifs_assert(inode_is_locked(inode));
616 err = dbg_check_synced_i_size(c, inode);
620 err = ubifs_budget_space(c, &req);
624 lock_2_inodes(dir, inode);
626 /* Handle O_TMPFILE corner case, it is allowed to link a O_TMPFILE. */
627 if (inode->i_nlink == 0)
628 ubifs_delete_orphan(c, inode->i_ino);
632 inode->i_ctime = ubifs_current_time(inode);
633 dir->i_size += sz_change;
634 dir_ui->ui_size = dir->i_size;
635 dir->i_mtime = dir->i_ctime = inode->i_ctime;
636 err = ubifs_jnl_update(c, dir, &dentry->d_name, inode, 0, 0);
639 unlock_2_inodes(dir, inode);
641 ubifs_release_budget(c, &req);
642 d_instantiate(dentry, inode);
646 dir->i_size -= sz_change;
647 dir_ui->ui_size = dir->i_size;
649 if (inode->i_nlink == 0)
650 ubifs_add_orphan(c, inode->i_ino);
651 unlock_2_inodes(dir, inode);
652 ubifs_release_budget(c, &req);
657 static int ubifs_unlink(struct inode *dir, struct dentry *dentry)
659 struct ubifs_info *c = dir->i_sb->s_fs_info;
660 struct inode *inode = d_inode(dentry);
661 struct ubifs_inode *dir_ui = ubifs_inode(dir);
662 int sz_change = CALC_DENT_SIZE(dentry->d_name.len);
663 int err, budgeted = 1;
664 struct ubifs_budget_req req = { .mod_dent = 1, .dirtied_ino = 2 };
665 unsigned int saved_nlink = inode->i_nlink;
668 * Budget request settings: deletion direntry, deletion inode (+1 for
669 * @dirtied_ino), changing the parent directory inode. If budgeting
670 * fails, go ahead anyway because we have extra space reserved for
674 dbg_gen("dent '%pd' from ino %lu (nlink %d) in dir ino %lu",
675 dentry, inode->i_ino,
676 inode->i_nlink, dir->i_ino);
677 ubifs_assert(inode_is_locked(dir));
678 ubifs_assert(inode_is_locked(inode));
679 err = dbg_check_synced_i_size(c, inode);
683 err = ubifs_budget_space(c, &req);
690 lock_2_inodes(dir, inode);
691 inode->i_ctime = ubifs_current_time(dir);
693 dir->i_size -= sz_change;
694 dir_ui->ui_size = dir->i_size;
695 dir->i_mtime = dir->i_ctime = inode->i_ctime;
696 err = ubifs_jnl_update(c, dir, &dentry->d_name, inode, 1, 0);
699 unlock_2_inodes(dir, inode);
702 ubifs_release_budget(c, &req);
704 /* We've deleted something - clean the "no space" flags */
705 c->bi.nospace = c->bi.nospace_rp = 0;
711 dir->i_size += sz_change;
712 dir_ui->ui_size = dir->i_size;
713 set_nlink(inode, saved_nlink);
714 unlock_2_inodes(dir, inode);
716 ubifs_release_budget(c, &req);
721 * check_dir_empty - check if a directory is empty or not.
722 * @c: UBIFS file-system description object
723 * @dir: VFS inode object of the directory to check
725 * This function checks if directory @dir is empty. Returns zero if the
726 * directory is empty, %-ENOTEMPTY if it is not, and other negative error codes
727 * in case of of errors.
729 static int check_dir_empty(struct ubifs_info *c, struct inode *dir)
731 struct qstr nm = { .name = NULL };
732 struct ubifs_dent_node *dent;
736 lowest_dent_key(c, &key, dir->i_ino);
737 dent = ubifs_tnc_next_ent(c, &key, &nm);
749 static int ubifs_rmdir(struct inode *dir, struct dentry *dentry)
751 struct ubifs_info *c = dir->i_sb->s_fs_info;
752 struct inode *inode = d_inode(dentry);
753 int sz_change = CALC_DENT_SIZE(dentry->d_name.len);
754 int err, budgeted = 1;
755 struct ubifs_inode *dir_ui = ubifs_inode(dir);
756 struct ubifs_budget_req req = { .mod_dent = 1, .dirtied_ino = 2 };
759 * Budget request settings: deletion direntry, deletion inode and
760 * changing the parent inode. If budgeting fails, go ahead anyway
761 * because we have extra space reserved for deletions.
764 dbg_gen("directory '%pd', ino %lu in dir ino %lu", dentry,
765 inode->i_ino, dir->i_ino);
766 ubifs_assert(inode_is_locked(dir));
767 ubifs_assert(inode_is_locked(inode));
768 err = check_dir_empty(c, d_inode(dentry));
772 err = ubifs_budget_space(c, &req);
779 lock_2_inodes(dir, inode);
780 inode->i_ctime = ubifs_current_time(dir);
783 dir->i_size -= sz_change;
784 dir_ui->ui_size = dir->i_size;
785 dir->i_mtime = dir->i_ctime = inode->i_ctime;
786 err = ubifs_jnl_update(c, dir, &dentry->d_name, inode, 1, 0);
789 unlock_2_inodes(dir, inode);
792 ubifs_release_budget(c, &req);
794 /* We've deleted something - clean the "no space" flags */
795 c->bi.nospace = c->bi.nospace_rp = 0;
801 dir->i_size += sz_change;
802 dir_ui->ui_size = dir->i_size;
805 unlock_2_inodes(dir, inode);
807 ubifs_release_budget(c, &req);
811 static int ubifs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
814 struct ubifs_inode *dir_ui = ubifs_inode(dir);
815 struct ubifs_info *c = dir->i_sb->s_fs_info;
816 int err, sz_change = CALC_DENT_SIZE(dentry->d_name.len);
817 struct ubifs_budget_req req = { .new_ino = 1, .new_dent = 1 };
820 * Budget request settings: new inode, new direntry and changing parent
824 dbg_gen("dent '%pd', mode %#hx in dir ino %lu",
825 dentry, mode, dir->i_ino);
827 err = ubifs_budget_space(c, &req);
831 inode = ubifs_new_inode(c, dir, S_IFDIR | mode);
833 err = PTR_ERR(inode);
837 err = ubifs_init_security(dir, inode, &dentry->d_name);
841 mutex_lock(&dir_ui->ui_mutex);
842 insert_inode_hash(inode);
845 dir->i_size += sz_change;
846 dir_ui->ui_size = dir->i_size;
847 dir->i_mtime = dir->i_ctime = inode->i_ctime;
848 err = ubifs_jnl_update(c, dir, &dentry->d_name, inode, 0, 0);
850 ubifs_err(c, "cannot create directory, error %d", err);
853 mutex_unlock(&dir_ui->ui_mutex);
855 ubifs_release_budget(c, &req);
856 d_instantiate(dentry, inode);
860 dir->i_size -= sz_change;
861 dir_ui->ui_size = dir->i_size;
863 mutex_unlock(&dir_ui->ui_mutex);
865 make_bad_inode(inode);
868 ubifs_release_budget(c, &req);
872 static int ubifs_mknod(struct inode *dir, struct dentry *dentry,
873 umode_t mode, dev_t rdev)
876 struct ubifs_inode *ui;
877 struct ubifs_inode *dir_ui = ubifs_inode(dir);
878 struct ubifs_info *c = dir->i_sb->s_fs_info;
879 union ubifs_dev_desc *dev = NULL;
880 int sz_change = CALC_DENT_SIZE(dentry->d_name.len);
882 struct ubifs_budget_req req = { .new_ino = 1, .new_dent = 1,
883 .new_ino_d = ALIGN(devlen, 8),
887 * Budget request settings: new inode, new direntry and changing parent
891 dbg_gen("dent '%pd' in dir ino %lu", dentry, dir->i_ino);
893 if (S_ISBLK(mode) || S_ISCHR(mode)) {
894 dev = kmalloc(sizeof(union ubifs_dev_desc), GFP_NOFS);
897 devlen = ubifs_encode_dev(dev, rdev);
900 err = ubifs_budget_space(c, &req);
906 inode = ubifs_new_inode(c, dir, mode);
909 err = PTR_ERR(inode);
913 init_special_inode(inode, inode->i_mode, rdev);
914 inode->i_size = ubifs_inode(inode)->ui_size = devlen;
915 ui = ubifs_inode(inode);
917 ui->data_len = devlen;
919 err = ubifs_init_security(dir, inode, &dentry->d_name);
923 mutex_lock(&dir_ui->ui_mutex);
924 dir->i_size += sz_change;
925 dir_ui->ui_size = dir->i_size;
926 dir->i_mtime = dir->i_ctime = inode->i_ctime;
927 err = ubifs_jnl_update(c, dir, &dentry->d_name, inode, 0, 0);
930 mutex_unlock(&dir_ui->ui_mutex);
932 ubifs_release_budget(c, &req);
933 insert_inode_hash(inode);
934 d_instantiate(dentry, inode);
938 dir->i_size -= sz_change;
939 dir_ui->ui_size = dir->i_size;
940 mutex_unlock(&dir_ui->ui_mutex);
942 make_bad_inode(inode);
945 ubifs_release_budget(c, &req);
949 static int ubifs_symlink(struct inode *dir, struct dentry *dentry,
953 struct ubifs_inode *ui;
954 struct ubifs_inode *dir_ui = ubifs_inode(dir);
955 struct ubifs_info *c = dir->i_sb->s_fs_info;
956 int err, len = strlen(symname);
957 int sz_change = CALC_DENT_SIZE(dentry->d_name.len);
958 struct ubifs_budget_req req = { .new_ino = 1, .new_dent = 1,
959 .new_ino_d = ALIGN(len, 8),
963 * Budget request settings: new inode, new direntry and changing parent
967 dbg_gen("dent '%pd', target '%s' in dir ino %lu", dentry,
968 symname, dir->i_ino);
970 if (len > UBIFS_MAX_INO_DATA)
971 return -ENAMETOOLONG;
973 err = ubifs_budget_space(c, &req);
977 inode = ubifs_new_inode(c, dir, S_IFLNK | S_IRWXUGO);
979 err = PTR_ERR(inode);
983 ui = ubifs_inode(inode);
984 ui->data = kmalloc(len + 1, GFP_NOFS);
990 memcpy(ui->data, symname, len);
991 ((char *)ui->data)[len] = '\0';
992 inode->i_link = ui->data;
994 * The terminating zero byte is not written to the flash media and it
995 * is put just to make later in-memory string processing simpler. Thus,
996 * data length is @len, not @len + %1.
999 inode->i_size = ubifs_inode(inode)->ui_size = len;
1001 err = ubifs_init_security(dir, inode, &dentry->d_name);
1005 mutex_lock(&dir_ui->ui_mutex);
1006 dir->i_size += sz_change;
1007 dir_ui->ui_size = dir->i_size;
1008 dir->i_mtime = dir->i_ctime = inode->i_ctime;
1009 err = ubifs_jnl_update(c, dir, &dentry->d_name, inode, 0, 0);
1012 mutex_unlock(&dir_ui->ui_mutex);
1014 ubifs_release_budget(c, &req);
1015 insert_inode_hash(inode);
1016 d_instantiate(dentry, inode);
1020 dir->i_size -= sz_change;
1021 dir_ui->ui_size = dir->i_size;
1022 mutex_unlock(&dir_ui->ui_mutex);
1024 make_bad_inode(inode);
1027 ubifs_release_budget(c, &req);
1032 * lock_4_inodes - a wrapper for locking three UBIFS inodes.
1033 * @inode1: first inode
1034 * @inode2: second inode
1035 * @inode3: third inode
1036 * @inode4: fouth inode
1038 * This function is used for 'ubifs_rename()' and @inode1 may be the same as
1039 * @inode2 whereas @inode3 and @inode4 may be %NULL.
1041 * We do not implement any tricks to guarantee strict lock ordering, because
1042 * VFS has already done it for us on the @i_mutex. So this is just a simple
1045 static void lock_4_inodes(struct inode *inode1, struct inode *inode2,
1046 struct inode *inode3, struct inode *inode4)
1048 mutex_lock_nested(&ubifs_inode(inode1)->ui_mutex, WB_MUTEX_1);
1049 if (inode2 != inode1)
1050 mutex_lock_nested(&ubifs_inode(inode2)->ui_mutex, WB_MUTEX_2);
1052 mutex_lock_nested(&ubifs_inode(inode3)->ui_mutex, WB_MUTEX_3);
1054 mutex_lock_nested(&ubifs_inode(inode4)->ui_mutex, WB_MUTEX_4);
1058 * unlock_4_inodes - a wrapper for unlocking three UBIFS inodes for rename.
1059 * @inode1: first inode
1060 * @inode2: second inode
1061 * @inode3: third inode
1062 * @inode4: fouth inode
1064 static void unlock_4_inodes(struct inode *inode1, struct inode *inode2,
1065 struct inode *inode3, struct inode *inode4)
1068 mutex_unlock(&ubifs_inode(inode4)->ui_mutex);
1070 mutex_unlock(&ubifs_inode(inode3)->ui_mutex);
1071 if (inode1 != inode2)
1072 mutex_unlock(&ubifs_inode(inode2)->ui_mutex);
1073 mutex_unlock(&ubifs_inode(inode1)->ui_mutex);
1076 static int do_rename(struct inode *old_dir, struct dentry *old_dentry,
1077 struct inode *new_dir, struct dentry *new_dentry,
1080 struct ubifs_info *c = old_dir->i_sb->s_fs_info;
1081 struct inode *old_inode = d_inode(old_dentry);
1082 struct inode *new_inode = d_inode(new_dentry);
1083 struct inode *whiteout = NULL;
1084 struct ubifs_inode *old_inode_ui = ubifs_inode(old_inode);
1085 struct ubifs_inode *whiteout_ui = NULL;
1086 int err, release, sync = 0, move = (new_dir != old_dir);
1087 int is_dir = S_ISDIR(old_inode->i_mode);
1088 int unlink = !!new_inode;
1089 int new_sz = CALC_DENT_SIZE(new_dentry->d_name.len);
1090 int old_sz = CALC_DENT_SIZE(old_dentry->d_name.len);
1091 struct ubifs_budget_req req = { .new_dent = 1, .mod_dent = 1,
1093 struct ubifs_budget_req ino_req = { .dirtied_ino = 1,
1094 .dirtied_ino_d = ALIGN(old_inode_ui->data_len, 8) };
1095 struct timespec time;
1096 unsigned int uninitialized_var(saved_nlink);
1099 * Budget request settings: deletion direntry, new direntry, removing
1100 * the old inode, and changing old and new parent directory inodes.
1102 * However, this operation also marks the target inode as dirty and
1103 * does not write it, so we allocate budget for the target inode
1107 dbg_gen("dent '%pd' ino %lu in dir ino %lu to dent '%pd' in dir ino %lu flags 0x%x",
1108 old_dentry, old_inode->i_ino, old_dir->i_ino,
1109 new_dentry, new_dir->i_ino, flags);
1112 ubifs_assert(inode_is_locked(new_inode));
1114 if (unlink && is_dir) {
1115 err = check_dir_empty(c, new_inode);
1120 err = ubifs_budget_space(c, &req);
1123 err = ubifs_budget_space(c, &ino_req);
1125 ubifs_release_budget(c, &req);
1129 if (flags & RENAME_WHITEOUT) {
1130 union ubifs_dev_desc *dev = NULL;
1132 dev = kmalloc(sizeof(union ubifs_dev_desc), GFP_NOFS);
1134 ubifs_release_budget(c, &req);
1135 ubifs_release_budget(c, &ino_req);
1139 err = do_tmpfile(old_dir, old_dentry, S_IFCHR | WHITEOUT_MODE, &whiteout);
1141 ubifs_release_budget(c, &req);
1142 ubifs_release_budget(c, &ino_req);
1147 spin_lock(&whiteout->i_lock);
1148 whiteout->i_state |= I_LINKABLE;
1149 spin_unlock(&whiteout->i_lock);
1151 whiteout_ui = ubifs_inode(whiteout);
1152 whiteout_ui->data = dev;
1153 whiteout_ui->data_len = ubifs_encode_dev(dev, MKDEV(0, 0));
1154 ubifs_assert(!whiteout_ui->dirty);
1157 lock_4_inodes(old_dir, new_dir, new_inode, whiteout);
1160 * Like most other Unix systems, set the @i_ctime for inodes on a
1163 time = ubifs_current_time(old_dir);
1164 old_inode->i_ctime = time;
1166 /* We must adjust parent link count when renaming directories */
1170 * @old_dir loses a link because we are moving
1171 * @old_inode to a different directory.
1173 drop_nlink(old_dir);
1175 * @new_dir only gains a link if we are not also
1176 * overwriting an existing directory.
1182 * @old_inode is not moving to a different directory,
1183 * but @old_dir still loses a link if we are
1184 * overwriting an existing directory.
1187 drop_nlink(old_dir);
1191 old_dir->i_size -= old_sz;
1192 ubifs_inode(old_dir)->ui_size = old_dir->i_size;
1193 old_dir->i_mtime = old_dir->i_ctime = time;
1194 new_dir->i_mtime = new_dir->i_ctime = time;
1197 * And finally, if we unlinked a direntry which happened to have the
1198 * same name as the moved direntry, we have to decrement @i_nlink of
1199 * the unlinked inode and change its ctime.
1203 * Directories cannot have hard-links, so if this is a
1204 * directory, just clear @i_nlink.
1206 saved_nlink = new_inode->i_nlink;
1208 clear_nlink(new_inode);
1210 drop_nlink(new_inode);
1211 new_inode->i_ctime = time;
1213 new_dir->i_size += new_sz;
1214 ubifs_inode(new_dir)->ui_size = new_dir->i_size;
1218 * Do not ask 'ubifs_jnl_rename()' to flush write-buffer if @old_inode
1219 * is dirty, because this will be done later on at the end of
1222 if (IS_SYNC(old_inode)) {
1223 sync = IS_DIRSYNC(old_dir) || IS_DIRSYNC(new_dir);
1224 if (unlink && IS_SYNC(new_inode))
1229 struct ubifs_budget_req wht_req = { .dirtied_ino = 1,
1231 ALIGN(ubifs_inode(whiteout)->data_len, 8) };
1233 err = ubifs_budget_space(c, &wht_req);
1235 ubifs_release_budget(c, &req);
1236 ubifs_release_budget(c, &ino_req);
1237 kfree(whiteout_ui->data);
1238 whiteout_ui->data_len = 0;
1243 inc_nlink(whiteout);
1244 mark_inode_dirty(whiteout);
1246 spin_lock(&whiteout->i_lock);
1247 whiteout->i_state &= ~I_LINKABLE;
1248 spin_unlock(&whiteout->i_lock);
1253 err = ubifs_jnl_rename(c, old_dir, old_dentry, new_dir, new_dentry, whiteout,
1258 unlock_4_inodes(old_dir, new_dir, new_inode, whiteout);
1259 ubifs_release_budget(c, &req);
1261 mutex_lock(&old_inode_ui->ui_mutex);
1262 release = old_inode_ui->dirty;
1263 mark_inode_dirty_sync(old_inode);
1264 mutex_unlock(&old_inode_ui->ui_mutex);
1267 ubifs_release_budget(c, &ino_req);
1268 if (IS_SYNC(old_inode))
1269 err = old_inode->i_sb->s_op->write_inode(old_inode, NULL);
1274 set_nlink(new_inode, saved_nlink);
1276 new_dir->i_size -= new_sz;
1277 ubifs_inode(new_dir)->ui_size = new_dir->i_size;
1279 old_dir->i_size += old_sz;
1280 ubifs_inode(old_dir)->ui_size = old_dir->i_size;
1285 drop_nlink(new_dir);
1292 drop_nlink(whiteout);
1295 unlock_4_inodes(old_dir, new_dir, new_inode, whiteout);
1296 ubifs_release_budget(c, &ino_req);
1297 ubifs_release_budget(c, &req);
1301 static int ubifs_xrename(struct inode *old_dir, struct dentry *old_dentry,
1302 struct inode *new_dir, struct dentry *new_dentry)
1304 struct ubifs_info *c = old_dir->i_sb->s_fs_info;
1305 struct ubifs_budget_req req = { .new_dent = 1, .mod_dent = 1,
1307 int sync = IS_DIRSYNC(old_dir) || IS_DIRSYNC(new_dir);
1308 struct inode *fst_inode = d_inode(old_dentry);
1309 struct inode *snd_inode = d_inode(new_dentry);
1310 struct timespec time;
1313 ubifs_assert(fst_inode && snd_inode);
1315 lock_4_inodes(old_dir, new_dir, NULL, NULL);
1317 time = ubifs_current_time(old_dir);
1318 fst_inode->i_ctime = time;
1319 snd_inode->i_ctime = time;
1320 old_dir->i_mtime = old_dir->i_ctime = time;
1321 new_dir->i_mtime = new_dir->i_ctime = time;
1323 if (old_dir != new_dir) {
1324 if (S_ISDIR(fst_inode->i_mode) && !S_ISDIR(snd_inode->i_mode)) {
1326 drop_nlink(old_dir);
1328 else if (!S_ISDIR(fst_inode->i_mode) && S_ISDIR(snd_inode->i_mode)) {
1329 drop_nlink(new_dir);
1334 err = ubifs_jnl_xrename(c, old_dir, old_dentry, new_dir, new_dentry,
1337 unlock_4_inodes(old_dir, new_dir, NULL, NULL);
1338 ubifs_release_budget(c, &req);
1343 static int ubifs_rename(struct inode *old_dir, struct dentry *old_dentry,
1344 struct inode *new_dir, struct dentry *new_dentry,
1347 if (flags & ~(RENAME_NOREPLACE | RENAME_WHITEOUT | RENAME_EXCHANGE))
1350 ubifs_assert(inode_is_locked(old_dir));
1351 ubifs_assert(inode_is_locked(new_dir));
1353 if (flags & RENAME_EXCHANGE)
1354 return ubifs_xrename(old_dir, old_dentry, new_dir, new_dentry);
1356 return do_rename(old_dir, old_dentry, new_dir, new_dentry, flags);
1359 int ubifs_getattr(struct vfsmount *mnt, struct dentry *dentry,
1363 struct inode *inode = d_inode(dentry);
1364 struct ubifs_inode *ui = ubifs_inode(inode);
1366 mutex_lock(&ui->ui_mutex);
1367 generic_fillattr(inode, stat);
1368 stat->blksize = UBIFS_BLOCK_SIZE;
1369 stat->size = ui->ui_size;
1372 * Unfortunately, the 'stat()' system call was designed for block
1373 * device based file systems, and it is not appropriate for UBIFS,
1374 * because UBIFS does not have notion of "block". For example, it is
1375 * difficult to tell how many block a directory takes - it actually
1376 * takes less than 300 bytes, but we have to round it to block size,
1377 * which introduces large mistake. This makes utilities like 'du' to
1378 * report completely senseless numbers. This is the reason why UBIFS
1379 * goes the same way as JFFS2 - it reports zero blocks for everything
1380 * but regular files, which makes more sense than reporting completely
1383 if (S_ISREG(inode->i_mode)) {
1384 size = ui->xattr_size;
1386 size = ALIGN(size, UBIFS_BLOCK_SIZE);
1388 * Note, user-space expects 512-byte blocks count irrespectively
1389 * of what was reported in @stat->size.
1391 stat->blocks = size >> 9;
1394 mutex_unlock(&ui->ui_mutex);
1398 const struct inode_operations ubifs_dir_inode_operations = {
1399 .lookup = ubifs_lookup,
1400 .create = ubifs_create,
1402 .symlink = ubifs_symlink,
1403 .unlink = ubifs_unlink,
1404 .mkdir = ubifs_mkdir,
1405 .rmdir = ubifs_rmdir,
1406 .mknod = ubifs_mknod,
1407 .rename = ubifs_rename,
1408 .setattr = ubifs_setattr,
1409 .getattr = ubifs_getattr,
1410 .listxattr = ubifs_listxattr,
1411 #ifdef CONFIG_UBIFS_ATIME_SUPPORT
1412 .update_time = ubifs_update_time,
1414 .tmpfile = ubifs_tmpfile,
1417 const struct file_operations ubifs_dir_operations = {
1418 .llseek = generic_file_llseek,
1419 .release = ubifs_dir_release,
1420 .read = generic_read_dir,
1421 .iterate_shared = ubifs_readdir,
1422 .fsync = ubifs_fsync,
1423 .unlocked_ioctl = ubifs_ioctl,
1424 #ifdef CONFIG_COMPAT
1425 .compat_ioctl = ubifs_compat_ioctl,