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);
382 ubifs_release_budget(c, &req);
384 ubifs_release_budget(c, &ino_req);
385 ubifs_err(c, "cannot create temporary file, error %d", err);
389 static int ubifs_tmpfile(struct inode *dir, struct dentry *dentry,
392 return do_tmpfile(dir, dentry, mode, NULL);
396 * vfs_dent_type - get VFS directory entry type.
397 * @type: UBIFS directory entry type
399 * This function converts UBIFS directory entry type into VFS directory entry
402 static unsigned int vfs_dent_type(uint8_t type)
405 case UBIFS_ITYPE_REG:
407 case UBIFS_ITYPE_DIR:
409 case UBIFS_ITYPE_LNK:
411 case UBIFS_ITYPE_BLK:
413 case UBIFS_ITYPE_CHR:
415 case UBIFS_ITYPE_FIFO:
417 case UBIFS_ITYPE_SOCK:
426 * The classical Unix view for directory is that it is a linear array of
427 * (name, inode number) entries. Linux/VFS assumes this model as well.
428 * Particularly, 'readdir()' call wants us to return a directory entry offset
429 * which later may be used to continue 'readdir()'ing the directory or to
430 * 'seek()' to that specific direntry. Obviously UBIFS does not really fit this
431 * model because directory entries are identified by keys, which may collide.
433 * UBIFS uses directory entry hash value for directory offsets, so
434 * 'seekdir()'/'telldir()' may not always work because of possible key
435 * collisions. But UBIFS guarantees that consecutive 'readdir()' calls work
436 * properly by means of saving full directory entry name in the private field
437 * of the file description object.
439 * This means that UBIFS cannot support NFS which requires full
440 * 'seekdir()'/'telldir()' support.
442 static int ubifs_readdir(struct file *file, struct dir_context *ctx)
447 struct ubifs_dent_node *dent;
448 struct inode *dir = file_inode(file);
449 struct ubifs_info *c = dir->i_sb->s_fs_info;
451 dbg_gen("dir ino %lu, f_pos %#llx", dir->i_ino, ctx->pos);
453 if (ctx->pos > UBIFS_S_KEY_HASH_MASK || ctx->pos == 2)
455 * The directory was seek'ed to a senseless position or there
456 * are no more entries.
460 if (file->f_version == 0) {
462 * The file was seek'ed, which means that @file->private_data
463 * is now invalid. This may also be just the first
464 * 'ubifs_readdir()' invocation, in which case
465 * @file->private_data is NULL, and the below code is
468 kfree(file->private_data);
469 file->private_data = NULL;
473 * 'generic_file_llseek()' unconditionally sets @file->f_version to
474 * zero, and we use this for detecting whether the file was seek'ed.
478 /* File positions 0 and 1 correspond to "." and ".." */
480 ubifs_assert(!file->private_data);
481 if (!dir_emit_dots(file, ctx))
484 /* Find the first entry in TNC and save it */
485 lowest_dent_key(c, &key, dir->i_ino);
487 dent = ubifs_tnc_next_ent(c, &key, &nm);
493 ctx->pos = key_hash_flash(c, &dent->key);
494 file->private_data = dent;
497 dent = file->private_data;
500 * The directory was seek'ed to and is now readdir'ed.
501 * Find the entry corresponding to @ctx->pos or the closest one.
503 dent_key_init_hash(c, &key, dir->i_ino, ctx->pos);
505 dent = ubifs_tnc_next_ent(c, &key, &nm);
510 ctx->pos = key_hash_flash(c, &dent->key);
511 file->private_data = dent;
515 dbg_gen("feed '%s', ino %llu, new f_pos %#x",
516 dent->name, (unsigned long long)le64_to_cpu(dent->inum),
517 key_hash_flash(c, &dent->key));
518 ubifs_assert(le64_to_cpu(dent->ch.sqnum) >
519 ubifs_inode(dir)->creat_sqnum);
521 nm.len = le16_to_cpu(dent->nlen);
522 if (!dir_emit(ctx, dent->name, nm.len,
523 le64_to_cpu(dent->inum),
524 vfs_dent_type(dent->type)))
527 /* Switch to the next entry */
528 key_read(c, &dent->key, &key);
529 nm.name = dent->name;
530 dent = ubifs_tnc_next_ent(c, &key, &nm);
536 kfree(file->private_data);
537 ctx->pos = key_hash_flash(c, &dent->key);
538 file->private_data = dent;
543 kfree(file->private_data);
544 file->private_data = NULL;
547 ubifs_err(c, "cannot find next direntry, error %d", err);
550 * -ENOENT is a non-fatal error in this context, the TNC uses
551 * it to indicate that the cursor moved past the current directory
552 * and readdir() has to stop.
557 /* 2 is a special value indicating that there are no more direntries */
562 /* Free saved readdir() state when the directory is closed */
563 static int ubifs_dir_release(struct inode *dir, struct file *file)
565 kfree(file->private_data);
566 file->private_data = NULL;
571 * lock_2_inodes - a wrapper for locking two UBIFS inodes.
572 * @inode1: first inode
573 * @inode2: second inode
575 * We do not implement any tricks to guarantee strict lock ordering, because
576 * VFS has already done it for us on the @i_mutex. So this is just a simple
579 static void lock_2_inodes(struct inode *inode1, struct inode *inode2)
581 mutex_lock_nested(&ubifs_inode(inode1)->ui_mutex, WB_MUTEX_1);
582 mutex_lock_nested(&ubifs_inode(inode2)->ui_mutex, WB_MUTEX_2);
586 * unlock_2_inodes - a wrapper for unlocking two UBIFS inodes.
587 * @inode1: first inode
588 * @inode2: second inode
590 static void unlock_2_inodes(struct inode *inode1, struct inode *inode2)
592 mutex_unlock(&ubifs_inode(inode2)->ui_mutex);
593 mutex_unlock(&ubifs_inode(inode1)->ui_mutex);
596 static int ubifs_link(struct dentry *old_dentry, struct inode *dir,
597 struct dentry *dentry)
599 struct ubifs_info *c = dir->i_sb->s_fs_info;
600 struct inode *inode = d_inode(old_dentry);
601 struct ubifs_inode *ui = ubifs_inode(inode);
602 struct ubifs_inode *dir_ui = ubifs_inode(dir);
603 int err, sz_change = CALC_DENT_SIZE(dentry->d_name.len);
604 struct ubifs_budget_req req = { .new_dent = 1, .dirtied_ino = 2,
605 .dirtied_ino_d = ALIGN(ui->data_len, 8) };
608 * Budget request settings: new direntry, changing the target inode,
609 * changing the parent inode.
612 dbg_gen("dent '%pd' to ino %lu (nlink %d) in dir ino %lu",
613 dentry, inode->i_ino,
614 inode->i_nlink, dir->i_ino);
615 ubifs_assert(inode_is_locked(dir));
616 ubifs_assert(inode_is_locked(inode));
618 err = dbg_check_synced_i_size(c, inode);
622 err = ubifs_budget_space(c, &req);
626 lock_2_inodes(dir, inode);
628 /* Handle O_TMPFILE corner case, it is allowed to link a O_TMPFILE. */
629 if (inode->i_nlink == 0)
630 ubifs_delete_orphan(c, inode->i_ino);
634 inode->i_ctime = ubifs_current_time(inode);
635 dir->i_size += sz_change;
636 dir_ui->ui_size = dir->i_size;
637 dir->i_mtime = dir->i_ctime = inode->i_ctime;
638 err = ubifs_jnl_update(c, dir, &dentry->d_name, inode, 0, 0);
641 unlock_2_inodes(dir, inode);
643 ubifs_release_budget(c, &req);
644 d_instantiate(dentry, inode);
648 dir->i_size -= sz_change;
649 dir_ui->ui_size = dir->i_size;
651 if (inode->i_nlink == 0)
652 ubifs_add_orphan(c, inode->i_ino);
653 unlock_2_inodes(dir, inode);
654 ubifs_release_budget(c, &req);
659 static int ubifs_unlink(struct inode *dir, struct dentry *dentry)
661 struct ubifs_info *c = dir->i_sb->s_fs_info;
662 struct inode *inode = d_inode(dentry);
663 struct ubifs_inode *dir_ui = ubifs_inode(dir);
664 int sz_change = CALC_DENT_SIZE(dentry->d_name.len);
665 int err, budgeted = 1;
666 struct ubifs_budget_req req = { .mod_dent = 1, .dirtied_ino = 2 };
667 unsigned int saved_nlink = inode->i_nlink;
670 * Budget request settings: deletion direntry, deletion inode (+1 for
671 * @dirtied_ino), changing the parent directory inode. If budgeting
672 * fails, go ahead anyway because we have extra space reserved for
676 dbg_gen("dent '%pd' from ino %lu (nlink %d) in dir ino %lu",
677 dentry, inode->i_ino,
678 inode->i_nlink, dir->i_ino);
679 ubifs_assert(inode_is_locked(dir));
680 ubifs_assert(inode_is_locked(inode));
681 err = dbg_check_synced_i_size(c, inode);
685 err = ubifs_budget_space(c, &req);
692 lock_2_inodes(dir, inode);
693 inode->i_ctime = ubifs_current_time(dir);
695 dir->i_size -= sz_change;
696 dir_ui->ui_size = dir->i_size;
697 dir->i_mtime = dir->i_ctime = inode->i_ctime;
698 err = ubifs_jnl_update(c, dir, &dentry->d_name, inode, 1, 0);
701 unlock_2_inodes(dir, inode);
704 ubifs_release_budget(c, &req);
706 /* We've deleted something - clean the "no space" flags */
707 c->bi.nospace = c->bi.nospace_rp = 0;
713 dir->i_size += sz_change;
714 dir_ui->ui_size = dir->i_size;
715 set_nlink(inode, saved_nlink);
716 unlock_2_inodes(dir, inode);
718 ubifs_release_budget(c, &req);
723 * check_dir_empty - check if a directory is empty or not.
724 * @c: UBIFS file-system description object
725 * @dir: VFS inode object of the directory to check
727 * This function checks if directory @dir is empty. Returns zero if the
728 * directory is empty, %-ENOTEMPTY if it is not, and other negative error codes
729 * in case of of errors.
731 static int check_dir_empty(struct ubifs_info *c, struct inode *dir)
733 struct qstr nm = { .name = NULL };
734 struct ubifs_dent_node *dent;
738 lowest_dent_key(c, &key, dir->i_ino);
739 dent = ubifs_tnc_next_ent(c, &key, &nm);
751 static int ubifs_rmdir(struct inode *dir, struct dentry *dentry)
753 struct ubifs_info *c = dir->i_sb->s_fs_info;
754 struct inode *inode = d_inode(dentry);
755 int sz_change = CALC_DENT_SIZE(dentry->d_name.len);
756 int err, budgeted = 1;
757 struct ubifs_inode *dir_ui = ubifs_inode(dir);
758 struct ubifs_budget_req req = { .mod_dent = 1, .dirtied_ino = 2 };
761 * Budget request settings: deletion direntry, deletion inode and
762 * changing the parent inode. If budgeting fails, go ahead anyway
763 * because we have extra space reserved for deletions.
766 dbg_gen("directory '%pd', ino %lu in dir ino %lu", dentry,
767 inode->i_ino, dir->i_ino);
768 ubifs_assert(inode_is_locked(dir));
769 ubifs_assert(inode_is_locked(inode));
770 err = check_dir_empty(c, d_inode(dentry));
774 err = ubifs_budget_space(c, &req);
781 lock_2_inodes(dir, inode);
782 inode->i_ctime = ubifs_current_time(dir);
785 dir->i_size -= sz_change;
786 dir_ui->ui_size = dir->i_size;
787 dir->i_mtime = dir->i_ctime = inode->i_ctime;
788 err = ubifs_jnl_update(c, dir, &dentry->d_name, inode, 1, 0);
791 unlock_2_inodes(dir, inode);
794 ubifs_release_budget(c, &req);
796 /* We've deleted something - clean the "no space" flags */
797 c->bi.nospace = c->bi.nospace_rp = 0;
803 dir->i_size += sz_change;
804 dir_ui->ui_size = dir->i_size;
807 unlock_2_inodes(dir, inode);
809 ubifs_release_budget(c, &req);
813 static int ubifs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
816 struct ubifs_inode *dir_ui = ubifs_inode(dir);
817 struct ubifs_info *c = dir->i_sb->s_fs_info;
818 int err, sz_change = CALC_DENT_SIZE(dentry->d_name.len);
819 struct ubifs_budget_req req = { .new_ino = 1, .new_dent = 1 };
822 * Budget request settings: new inode, new direntry and changing parent
826 dbg_gen("dent '%pd', mode %#hx in dir ino %lu",
827 dentry, mode, dir->i_ino);
829 err = ubifs_budget_space(c, &req);
833 inode = ubifs_new_inode(c, dir, S_IFDIR | mode);
835 err = PTR_ERR(inode);
839 err = ubifs_init_security(dir, inode, &dentry->d_name);
843 mutex_lock(&dir_ui->ui_mutex);
844 insert_inode_hash(inode);
847 dir->i_size += sz_change;
848 dir_ui->ui_size = dir->i_size;
849 dir->i_mtime = dir->i_ctime = inode->i_ctime;
850 err = ubifs_jnl_update(c, dir, &dentry->d_name, inode, 0, 0);
852 ubifs_err(c, "cannot create directory, error %d", err);
855 mutex_unlock(&dir_ui->ui_mutex);
857 ubifs_release_budget(c, &req);
858 d_instantiate(dentry, inode);
862 dir->i_size -= sz_change;
863 dir_ui->ui_size = dir->i_size;
865 mutex_unlock(&dir_ui->ui_mutex);
867 make_bad_inode(inode);
870 ubifs_release_budget(c, &req);
874 static int ubifs_mknod(struct inode *dir, struct dentry *dentry,
875 umode_t mode, dev_t rdev)
878 struct ubifs_inode *ui;
879 struct ubifs_inode *dir_ui = ubifs_inode(dir);
880 struct ubifs_info *c = dir->i_sb->s_fs_info;
881 union ubifs_dev_desc *dev = NULL;
882 int sz_change = CALC_DENT_SIZE(dentry->d_name.len);
884 struct ubifs_budget_req req = { .new_ino = 1, .new_dent = 1,
885 .new_ino_d = ALIGN(devlen, 8),
889 * Budget request settings: new inode, new direntry and changing parent
893 dbg_gen("dent '%pd' in dir ino %lu", dentry, dir->i_ino);
895 if (S_ISBLK(mode) || S_ISCHR(mode)) {
896 dev = kmalloc(sizeof(union ubifs_dev_desc), GFP_NOFS);
899 devlen = ubifs_encode_dev(dev, rdev);
902 err = ubifs_budget_space(c, &req);
908 inode = ubifs_new_inode(c, dir, mode);
911 err = PTR_ERR(inode);
915 init_special_inode(inode, inode->i_mode, rdev);
916 inode->i_size = ubifs_inode(inode)->ui_size = devlen;
917 ui = ubifs_inode(inode);
919 ui->data_len = devlen;
921 err = ubifs_init_security(dir, inode, &dentry->d_name);
925 mutex_lock(&dir_ui->ui_mutex);
926 dir->i_size += sz_change;
927 dir_ui->ui_size = dir->i_size;
928 dir->i_mtime = dir->i_ctime = inode->i_ctime;
929 err = ubifs_jnl_update(c, dir, &dentry->d_name, inode, 0, 0);
932 mutex_unlock(&dir_ui->ui_mutex);
934 ubifs_release_budget(c, &req);
935 insert_inode_hash(inode);
936 d_instantiate(dentry, inode);
940 dir->i_size -= sz_change;
941 dir_ui->ui_size = dir->i_size;
942 mutex_unlock(&dir_ui->ui_mutex);
944 make_bad_inode(inode);
947 ubifs_release_budget(c, &req);
951 static int ubifs_symlink(struct inode *dir, struct dentry *dentry,
955 struct ubifs_inode *ui;
956 struct ubifs_inode *dir_ui = ubifs_inode(dir);
957 struct ubifs_info *c = dir->i_sb->s_fs_info;
958 int err, len = strlen(symname);
959 int sz_change = CALC_DENT_SIZE(dentry->d_name.len);
960 struct ubifs_budget_req req = { .new_ino = 1, .new_dent = 1,
961 .new_ino_d = ALIGN(len, 8),
965 * Budget request settings: new inode, new direntry and changing parent
969 dbg_gen("dent '%pd', target '%s' in dir ino %lu", dentry,
970 symname, dir->i_ino);
972 if (len > UBIFS_MAX_INO_DATA)
973 return -ENAMETOOLONG;
975 err = ubifs_budget_space(c, &req);
979 inode = ubifs_new_inode(c, dir, S_IFLNK | S_IRWXUGO);
981 err = PTR_ERR(inode);
985 ui = ubifs_inode(inode);
986 ui->data = kmalloc(len + 1, GFP_NOFS);
992 memcpy(ui->data, symname, len);
993 ((char *)ui->data)[len] = '\0';
994 inode->i_link = ui->data;
996 * The terminating zero byte is not written to the flash media and it
997 * is put just to make later in-memory string processing simpler. Thus,
998 * data length is @len, not @len + %1.
1001 inode->i_size = ubifs_inode(inode)->ui_size = len;
1003 err = ubifs_init_security(dir, inode, &dentry->d_name);
1007 mutex_lock(&dir_ui->ui_mutex);
1008 dir->i_size += sz_change;
1009 dir_ui->ui_size = dir->i_size;
1010 dir->i_mtime = dir->i_ctime = inode->i_ctime;
1011 err = ubifs_jnl_update(c, dir, &dentry->d_name, inode, 0, 0);
1014 mutex_unlock(&dir_ui->ui_mutex);
1016 ubifs_release_budget(c, &req);
1017 insert_inode_hash(inode);
1018 d_instantiate(dentry, inode);
1022 dir->i_size -= sz_change;
1023 dir_ui->ui_size = dir->i_size;
1024 mutex_unlock(&dir_ui->ui_mutex);
1026 make_bad_inode(inode);
1029 ubifs_release_budget(c, &req);
1034 * lock_4_inodes - a wrapper for locking three UBIFS inodes.
1035 * @inode1: first inode
1036 * @inode2: second inode
1037 * @inode3: third inode
1038 * @inode4: fouth inode
1040 * This function is used for 'ubifs_rename()' and @inode1 may be the same as
1041 * @inode2 whereas @inode3 and @inode4 may be %NULL.
1043 * We do not implement any tricks to guarantee strict lock ordering, because
1044 * VFS has already done it for us on the @i_mutex. So this is just a simple
1047 static void lock_4_inodes(struct inode *inode1, struct inode *inode2,
1048 struct inode *inode3, struct inode *inode4)
1050 mutex_lock_nested(&ubifs_inode(inode1)->ui_mutex, WB_MUTEX_1);
1051 if (inode2 != inode1)
1052 mutex_lock_nested(&ubifs_inode(inode2)->ui_mutex, WB_MUTEX_2);
1054 mutex_lock_nested(&ubifs_inode(inode3)->ui_mutex, WB_MUTEX_3);
1056 mutex_lock_nested(&ubifs_inode(inode4)->ui_mutex, WB_MUTEX_4);
1060 * unlock_4_inodes - a wrapper for unlocking three UBIFS inodes for rename.
1061 * @inode1: first inode
1062 * @inode2: second inode
1063 * @inode3: third inode
1064 * @inode4: fouth inode
1066 static void unlock_4_inodes(struct inode *inode1, struct inode *inode2,
1067 struct inode *inode3, struct inode *inode4)
1070 mutex_unlock(&ubifs_inode(inode4)->ui_mutex);
1072 mutex_unlock(&ubifs_inode(inode3)->ui_mutex);
1073 if (inode1 != inode2)
1074 mutex_unlock(&ubifs_inode(inode2)->ui_mutex);
1075 mutex_unlock(&ubifs_inode(inode1)->ui_mutex);
1078 static int do_rename(struct inode *old_dir, struct dentry *old_dentry,
1079 struct inode *new_dir, struct dentry *new_dentry,
1082 struct ubifs_info *c = old_dir->i_sb->s_fs_info;
1083 struct inode *old_inode = d_inode(old_dentry);
1084 struct inode *new_inode = d_inode(new_dentry);
1085 struct inode *whiteout = NULL;
1086 struct ubifs_inode *old_inode_ui = ubifs_inode(old_inode);
1087 struct ubifs_inode *whiteout_ui = NULL;
1088 int err, release, sync = 0, move = (new_dir != old_dir);
1089 int is_dir = S_ISDIR(old_inode->i_mode);
1090 int unlink = !!new_inode;
1091 int new_sz = CALC_DENT_SIZE(new_dentry->d_name.len);
1092 int old_sz = CALC_DENT_SIZE(old_dentry->d_name.len);
1093 struct ubifs_budget_req req = { .new_dent = 1, .mod_dent = 1,
1095 struct ubifs_budget_req ino_req = { .dirtied_ino = 1,
1096 .dirtied_ino_d = ALIGN(old_inode_ui->data_len, 8) };
1097 struct timespec time;
1098 unsigned int uninitialized_var(saved_nlink);
1101 * Budget request settings: deletion direntry, new direntry, removing
1102 * the old inode, and changing old and new parent directory inodes.
1104 * However, this operation also marks the target inode as dirty and
1105 * does not write it, so we allocate budget for the target inode
1109 dbg_gen("dent '%pd' ino %lu in dir ino %lu to dent '%pd' in dir ino %lu flags 0x%x",
1110 old_dentry, old_inode->i_ino, old_dir->i_ino,
1111 new_dentry, new_dir->i_ino, flags);
1114 ubifs_assert(inode_is_locked(new_inode));
1116 if (unlink && is_dir) {
1117 err = check_dir_empty(c, new_inode);
1122 err = ubifs_budget_space(c, &req);
1125 err = ubifs_budget_space(c, &ino_req);
1127 ubifs_release_budget(c, &req);
1131 if (flags & RENAME_WHITEOUT) {
1132 union ubifs_dev_desc *dev = NULL;
1134 dev = kmalloc(sizeof(union ubifs_dev_desc), GFP_NOFS);
1136 ubifs_release_budget(c, &req);
1137 ubifs_release_budget(c, &ino_req);
1141 err = do_tmpfile(old_dir, old_dentry, S_IFCHR | WHITEOUT_MODE, &whiteout);
1143 ubifs_release_budget(c, &req);
1144 ubifs_release_budget(c, &ino_req);
1149 spin_lock(&whiteout->i_lock);
1150 whiteout->i_state |= I_LINKABLE;
1151 spin_unlock(&whiteout->i_lock);
1153 whiteout_ui = ubifs_inode(whiteout);
1154 whiteout_ui->data = dev;
1155 whiteout_ui->data_len = ubifs_encode_dev(dev, MKDEV(0, 0));
1156 ubifs_assert(!whiteout_ui->dirty);
1159 lock_4_inodes(old_dir, new_dir, new_inode, whiteout);
1162 * Like most other Unix systems, set the @i_ctime for inodes on a
1165 time = ubifs_current_time(old_dir);
1166 old_inode->i_ctime = time;
1168 /* We must adjust parent link count when renaming directories */
1172 * @old_dir loses a link because we are moving
1173 * @old_inode to a different directory.
1175 drop_nlink(old_dir);
1177 * @new_dir only gains a link if we are not also
1178 * overwriting an existing directory.
1184 * @old_inode is not moving to a different directory,
1185 * but @old_dir still loses a link if we are
1186 * overwriting an existing directory.
1189 drop_nlink(old_dir);
1193 old_dir->i_size -= old_sz;
1194 ubifs_inode(old_dir)->ui_size = old_dir->i_size;
1195 old_dir->i_mtime = old_dir->i_ctime = time;
1196 new_dir->i_mtime = new_dir->i_ctime = time;
1199 * And finally, if we unlinked a direntry which happened to have the
1200 * same name as the moved direntry, we have to decrement @i_nlink of
1201 * the unlinked inode and change its ctime.
1205 * Directories cannot have hard-links, so if this is a
1206 * directory, just clear @i_nlink.
1208 saved_nlink = new_inode->i_nlink;
1210 clear_nlink(new_inode);
1212 drop_nlink(new_inode);
1213 new_inode->i_ctime = time;
1215 new_dir->i_size += new_sz;
1216 ubifs_inode(new_dir)->ui_size = new_dir->i_size;
1220 * Do not ask 'ubifs_jnl_rename()' to flush write-buffer if @old_inode
1221 * is dirty, because this will be done later on at the end of
1224 if (IS_SYNC(old_inode)) {
1225 sync = IS_DIRSYNC(old_dir) || IS_DIRSYNC(new_dir);
1226 if (unlink && IS_SYNC(new_inode))
1231 struct ubifs_budget_req wht_req = { .dirtied_ino = 1,
1233 ALIGN(ubifs_inode(whiteout)->data_len, 8) };
1235 err = ubifs_budget_space(c, &wht_req);
1237 ubifs_release_budget(c, &req);
1238 ubifs_release_budget(c, &ino_req);
1239 kfree(whiteout_ui->data);
1240 whiteout_ui->data_len = 0;
1245 inc_nlink(whiteout);
1246 mark_inode_dirty(whiteout);
1248 spin_lock(&whiteout->i_lock);
1249 whiteout->i_state &= ~I_LINKABLE;
1250 spin_unlock(&whiteout->i_lock);
1255 err = ubifs_jnl_rename(c, old_dir, old_dentry, new_dir, new_dentry, whiteout,
1260 unlock_4_inodes(old_dir, new_dir, new_inode, whiteout);
1261 ubifs_release_budget(c, &req);
1263 mutex_lock(&old_inode_ui->ui_mutex);
1264 release = old_inode_ui->dirty;
1265 mark_inode_dirty_sync(old_inode);
1266 mutex_unlock(&old_inode_ui->ui_mutex);
1269 ubifs_release_budget(c, &ino_req);
1270 if (IS_SYNC(old_inode))
1271 err = old_inode->i_sb->s_op->write_inode(old_inode, NULL);
1276 set_nlink(new_inode, saved_nlink);
1278 new_dir->i_size -= new_sz;
1279 ubifs_inode(new_dir)->ui_size = new_dir->i_size;
1281 old_dir->i_size += old_sz;
1282 ubifs_inode(old_dir)->ui_size = old_dir->i_size;
1287 drop_nlink(new_dir);
1294 drop_nlink(whiteout);
1297 unlock_4_inodes(old_dir, new_dir, new_inode, whiteout);
1298 ubifs_release_budget(c, &ino_req);
1299 ubifs_release_budget(c, &req);
1303 static int ubifs_xrename(struct inode *old_dir, struct dentry *old_dentry,
1304 struct inode *new_dir, struct dentry *new_dentry)
1306 struct ubifs_info *c = old_dir->i_sb->s_fs_info;
1307 struct ubifs_budget_req req = { .new_dent = 1, .mod_dent = 1,
1309 int sync = IS_DIRSYNC(old_dir) || IS_DIRSYNC(new_dir);
1310 struct inode *fst_inode = d_inode(old_dentry);
1311 struct inode *snd_inode = d_inode(new_dentry);
1312 struct timespec time;
1315 ubifs_assert(fst_inode && snd_inode);
1317 lock_4_inodes(old_dir, new_dir, NULL, NULL);
1319 time = ubifs_current_time(old_dir);
1320 fst_inode->i_ctime = time;
1321 snd_inode->i_ctime = time;
1322 old_dir->i_mtime = old_dir->i_ctime = time;
1323 new_dir->i_mtime = new_dir->i_ctime = time;
1325 if (old_dir != new_dir) {
1326 if (S_ISDIR(fst_inode->i_mode) && !S_ISDIR(snd_inode->i_mode)) {
1328 drop_nlink(old_dir);
1330 else if (!S_ISDIR(fst_inode->i_mode) && S_ISDIR(snd_inode->i_mode)) {
1331 drop_nlink(new_dir);
1336 err = ubifs_jnl_xrename(c, old_dir, old_dentry, new_dir, new_dentry,
1339 unlock_4_inodes(old_dir, new_dir, NULL, NULL);
1340 ubifs_release_budget(c, &req);
1345 static int ubifs_rename(struct inode *old_dir, struct dentry *old_dentry,
1346 struct inode *new_dir, struct dentry *new_dentry,
1349 if (flags & ~(RENAME_NOREPLACE | RENAME_WHITEOUT | RENAME_EXCHANGE))
1352 ubifs_assert(inode_is_locked(old_dir));
1353 ubifs_assert(inode_is_locked(new_dir));
1355 if (flags & RENAME_EXCHANGE)
1356 return ubifs_xrename(old_dir, old_dentry, new_dir, new_dentry);
1358 return do_rename(old_dir, old_dentry, new_dir, new_dentry, flags);
1361 int ubifs_getattr(struct vfsmount *mnt, struct dentry *dentry,
1365 struct inode *inode = d_inode(dentry);
1366 struct ubifs_inode *ui = ubifs_inode(inode);
1368 mutex_lock(&ui->ui_mutex);
1369 generic_fillattr(inode, stat);
1370 stat->blksize = UBIFS_BLOCK_SIZE;
1371 stat->size = ui->ui_size;
1374 * Unfortunately, the 'stat()' system call was designed for block
1375 * device based file systems, and it is not appropriate for UBIFS,
1376 * because UBIFS does not have notion of "block". For example, it is
1377 * difficult to tell how many block a directory takes - it actually
1378 * takes less than 300 bytes, but we have to round it to block size,
1379 * which introduces large mistake. This makes utilities like 'du' to
1380 * report completely senseless numbers. This is the reason why UBIFS
1381 * goes the same way as JFFS2 - it reports zero blocks for everything
1382 * but regular files, which makes more sense than reporting completely
1385 if (S_ISREG(inode->i_mode)) {
1386 size = ui->xattr_size;
1388 size = ALIGN(size, UBIFS_BLOCK_SIZE);
1390 * Note, user-space expects 512-byte blocks count irrespectively
1391 * of what was reported in @stat->size.
1393 stat->blocks = size >> 9;
1396 mutex_unlock(&ui->ui_mutex);
1400 const struct inode_operations ubifs_dir_inode_operations = {
1401 .lookup = ubifs_lookup,
1402 .create = ubifs_create,
1404 .symlink = ubifs_symlink,
1405 .unlink = ubifs_unlink,
1406 .mkdir = ubifs_mkdir,
1407 .rmdir = ubifs_rmdir,
1408 .mknod = ubifs_mknod,
1409 .rename = ubifs_rename,
1410 .setattr = ubifs_setattr,
1411 .getattr = ubifs_getattr,
1412 .listxattr = ubifs_listxattr,
1413 #ifdef CONFIG_UBIFS_ATIME_SUPPORT
1414 .update_time = ubifs_update_time,
1416 .tmpfile = ubifs_tmpfile,
1419 const struct file_operations ubifs_dir_operations = {
1420 .llseek = generic_file_llseek,
1421 .release = ubifs_dir_release,
1422 .read = generic_read_dir,
1423 .iterate_shared = ubifs_readdir,
1424 .fsync = ubifs_fsync,
1425 .unlocked_ioctl = ubifs_ioctl,
1426 #ifdef CONFIG_COMPAT
1427 .compat_ioctl = ubifs_compat_ioctl,