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, struct inode *dir,
93 struct ubifs_inode *ui;
94 bool encrypted = false;
96 if (ubifs_crypt_is_encrypted(dir)) {
97 err = fscrypt_get_encryption_info(dir);
99 ubifs_err(c, "fscrypt_get_encryption_info failed: %i", err);
103 if (!fscrypt_has_encryption_key(dir))
104 return ERR_PTR(-EPERM);
109 inode = new_inode(c->vfs_sb);
110 ui = ubifs_inode(inode);
112 return ERR_PTR(-ENOMEM);
115 * Set 'S_NOCMTIME' to prevent VFS form updating [mc]time of inodes and
116 * marking them dirty in file write path (see 'file_update_time()').
117 * UBIFS has to fully control "clean <-> dirty" transitions of inodes
118 * to make budgeting work.
120 inode->i_flags |= S_NOCMTIME;
122 inode_init_owner(inode, dir, mode);
123 inode->i_mtime = inode->i_atime = inode->i_ctime =
125 inode->i_mapping->nrpages = 0;
127 switch (mode & S_IFMT) {
129 inode->i_mapping->a_ops = &ubifs_file_address_operations;
130 inode->i_op = &ubifs_file_inode_operations;
131 inode->i_fop = &ubifs_file_operations;
134 inode->i_op = &ubifs_dir_inode_operations;
135 inode->i_fop = &ubifs_dir_operations;
136 inode->i_size = ui->ui_size = UBIFS_INO_NODE_SZ;
139 inode->i_op = &ubifs_symlink_inode_operations;
145 inode->i_op = &ubifs_file_inode_operations;
152 ui->flags = inherit_flags(dir, mode);
153 ubifs_set_inode_flags(inode);
155 ui->compr_type = c->default_compr;
157 ui->compr_type = UBIFS_COMPR_NONE;
158 ui->synced_i_size = 0;
160 spin_lock(&c->cnt_lock);
161 /* Inode number overflow is currently not supported */
162 if (c->highest_inum >= INUM_WARN_WATERMARK) {
163 if (c->highest_inum >= INUM_WATERMARK) {
164 spin_unlock(&c->cnt_lock);
165 ubifs_err(c, "out of inode numbers");
166 make_bad_inode(inode);
168 return ERR_PTR(-EINVAL);
170 ubifs_warn(c, "running out of inode numbers (current %lu, max %u)",
171 (unsigned long)c->highest_inum, INUM_WATERMARK);
174 inode->i_ino = ++c->highest_inum;
176 * The creation sequence number remains with this inode for its
177 * lifetime. All nodes for this inode have a greater sequence number,
178 * and so it is possible to distinguish obsolete nodes belonging to a
179 * previous incarnation of the same inode number - for example, for the
180 * purpose of rebuilding the index.
182 ui->creat_sqnum = ++c->max_sqnum;
183 spin_unlock(&c->cnt_lock);
186 err = fscrypt_inherit_context(dir, inode, &encrypted, true);
188 ubifs_err(c, "fscrypt_inherit_context failed: %i", err);
189 make_bad_inode(inode);
198 static int dbg_check_name(const struct ubifs_info *c,
199 const struct ubifs_dent_node *dent,
200 const struct fscrypt_name *nm)
202 if (!dbg_is_chk_gen(c))
204 if (le16_to_cpu(dent->nlen) != fname_len(nm))
206 if (memcmp(dent->name, fname_name(nm), fname_len(nm)))
211 static struct dentry *ubifs_lookup(struct inode *dir, struct dentry *dentry,
216 struct inode *inode = NULL;
217 struct ubifs_dent_node *dent;
218 struct ubifs_info *c = dir->i_sb->s_fs_info;
219 struct fscrypt_name nm;
221 dbg_gen("'%pd' in dir ino %lu", dentry, dir->i_ino);
223 err = fscrypt_prepare_lookup(dir, dentry, flags);
227 err = fscrypt_setup_filename(dir, &dentry->d_name, 1, &nm);
231 if (fname_len(&nm) > UBIFS_MAX_NLEN) {
236 dent = kmalloc(UBIFS_MAX_DENT_NODE_SZ, GFP_NOFS);
243 ubifs_assert(fname_len(&nm) == 0);
244 ubifs_assert(fname_name(&nm) == NULL);
245 dent_key_init_hash(c, &key, dir->i_ino, nm.hash);
246 err = ubifs_tnc_lookup_dh(c, &key, dent, nm.minor_hash);
248 dent_key_init(c, &key, dir->i_ino, &nm);
249 err = ubifs_tnc_lookup_nm(c, &key, dent, &nm);
253 if (err == -ENOENT) {
254 dbg_gen("not found");
260 if (dbg_check_name(c, dent, &nm)) {
265 inode = ubifs_iget(dir->i_sb, le64_to_cpu(dent->inum));
268 * This should not happen. Probably the file-system needs
271 err = PTR_ERR(inode);
272 ubifs_err(c, "dead directory entry '%pd', error %d",
274 ubifs_ro_mode(c, err);
278 if (ubifs_crypt_is_encrypted(dir) &&
279 (S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode)) &&
280 !fscrypt_has_permitted_context(dir, inode)) {
281 ubifs_warn(c, "Inconsistent encryption contexts: %lu/%lu",
282 dir->i_ino, inode->i_ino);
289 fscrypt_free_filename(&nm);
291 * Note, d_splice_alias() would be required instead if we supported
294 d_add(dentry, inode);
302 fscrypt_free_filename(&nm);
306 static int ubifs_create(struct inode *dir, struct dentry *dentry, umode_t mode,
310 struct ubifs_info *c = dir->i_sb->s_fs_info;
311 struct ubifs_budget_req req = { .new_ino = 1, .new_dent = 1,
313 struct ubifs_inode *dir_ui = ubifs_inode(dir);
314 struct fscrypt_name nm;
318 * Budget request settings: new inode, new direntry, changing the
319 * parent directory inode.
322 dbg_gen("dent '%pd', mode %#hx in dir ino %lu",
323 dentry, mode, dir->i_ino);
325 err = ubifs_budget_space(c, &req);
329 err = fscrypt_setup_filename(dir, &dentry->d_name, 0, &nm);
333 sz_change = CALC_DENT_SIZE(fname_len(&nm));
335 inode = ubifs_new_inode(c, dir, mode);
337 err = PTR_ERR(inode);
341 err = ubifs_init_security(dir, inode, &dentry->d_name);
345 mutex_lock(&dir_ui->ui_mutex);
346 dir->i_size += sz_change;
347 dir_ui->ui_size = dir->i_size;
348 dir->i_mtime = dir->i_ctime = inode->i_ctime;
349 err = ubifs_jnl_update(c, dir, &nm, inode, 0, 0);
352 mutex_unlock(&dir_ui->ui_mutex);
354 ubifs_release_budget(c, &req);
355 fscrypt_free_filename(&nm);
356 insert_inode_hash(inode);
357 d_instantiate(dentry, inode);
361 dir->i_size -= sz_change;
362 dir_ui->ui_size = dir->i_size;
363 mutex_unlock(&dir_ui->ui_mutex);
365 make_bad_inode(inode);
368 fscrypt_free_filename(&nm);
370 ubifs_release_budget(c, &req);
371 ubifs_err(c, "cannot create regular file, error %d", err);
375 static int do_tmpfile(struct inode *dir, struct dentry *dentry,
376 umode_t mode, struct inode **whiteout)
379 struct ubifs_info *c = dir->i_sb->s_fs_info;
380 struct ubifs_budget_req req = { .new_ino = 1, .new_dent = 1};
381 struct ubifs_budget_req ino_req = { .dirtied_ino = 1 };
382 struct ubifs_inode *ui, *dir_ui = ubifs_inode(dir);
383 int err, instantiated = 0;
384 struct fscrypt_name nm;
387 * Budget request settings: new dirty inode, new direntry,
388 * budget for dirtied inode will be released via writeback.
391 dbg_gen("dent '%pd', mode %#hx in dir ino %lu",
392 dentry, mode, dir->i_ino);
394 err = fscrypt_setup_filename(dir, &dentry->d_name, 0, &nm);
398 err = ubifs_budget_space(c, &req);
400 fscrypt_free_filename(&nm);
404 err = ubifs_budget_space(c, &ino_req);
406 ubifs_release_budget(c, &req);
407 fscrypt_free_filename(&nm);
411 inode = ubifs_new_inode(c, dir, mode);
413 err = PTR_ERR(inode);
416 ui = ubifs_inode(inode);
419 init_special_inode(inode, inode->i_mode, WHITEOUT_DEV);
420 ubifs_assert(inode->i_op == &ubifs_file_inode_operations);
423 err = ubifs_init_security(dir, inode, &dentry->d_name);
427 mutex_lock(&ui->ui_mutex);
428 insert_inode_hash(inode);
431 mark_inode_dirty(inode);
435 d_tmpfile(dentry, inode);
437 ubifs_assert(ui->dirty);
440 mutex_unlock(&ui->ui_mutex);
442 mutex_lock(&dir_ui->ui_mutex);
443 err = ubifs_jnl_update(c, dir, &nm, inode, 1, 0);
446 mutex_unlock(&dir_ui->ui_mutex);
448 ubifs_release_budget(c, &req);
453 mutex_unlock(&dir_ui->ui_mutex);
455 make_bad_inode(inode);
459 ubifs_release_budget(c, &req);
461 ubifs_release_budget(c, &ino_req);
462 fscrypt_free_filename(&nm);
463 ubifs_err(c, "cannot create temporary file, error %d", err);
467 static int ubifs_tmpfile(struct inode *dir, struct dentry *dentry,
470 return do_tmpfile(dir, dentry, mode, NULL);
474 * vfs_dent_type - get VFS directory entry type.
475 * @type: UBIFS directory entry type
477 * This function converts UBIFS directory entry type into VFS directory entry
480 static unsigned int vfs_dent_type(uint8_t type)
483 case UBIFS_ITYPE_REG:
485 case UBIFS_ITYPE_DIR:
487 case UBIFS_ITYPE_LNK:
489 case UBIFS_ITYPE_BLK:
491 case UBIFS_ITYPE_CHR:
493 case UBIFS_ITYPE_FIFO:
495 case UBIFS_ITYPE_SOCK:
504 * The classical Unix view for directory is that it is a linear array of
505 * (name, inode number) entries. Linux/VFS assumes this model as well.
506 * Particularly, 'readdir()' call wants us to return a directory entry offset
507 * which later may be used to continue 'readdir()'ing the directory or to
508 * 'seek()' to that specific direntry. Obviously UBIFS does not really fit this
509 * model because directory entries are identified by keys, which may collide.
511 * UBIFS uses directory entry hash value for directory offsets, so
512 * 'seekdir()'/'telldir()' may not always work because of possible key
513 * collisions. But UBIFS guarantees that consecutive 'readdir()' calls work
514 * properly by means of saving full directory entry name in the private field
515 * of the file description object.
517 * This means that UBIFS cannot support NFS which requires full
518 * 'seekdir()'/'telldir()' support.
520 static int ubifs_readdir(struct file *file, struct dir_context *ctx)
522 int fstr_real_len = 0, err = 0;
523 struct fscrypt_name nm;
524 struct fscrypt_str fstr = {0};
526 struct ubifs_dent_node *dent;
527 struct inode *dir = file_inode(file);
528 struct ubifs_info *c = dir->i_sb->s_fs_info;
529 bool encrypted = ubifs_crypt_is_encrypted(dir);
531 dbg_gen("dir ino %lu, f_pos %#llx", dir->i_ino, ctx->pos);
533 if (ctx->pos > UBIFS_S_KEY_HASH_MASK || ctx->pos == 2)
535 * The directory was seek'ed to a senseless position or there
536 * are no more entries.
541 err = fscrypt_get_encryption_info(dir);
542 if (err && err != -ENOKEY)
545 err = fscrypt_fname_alloc_buffer(dir, UBIFS_MAX_NLEN, &fstr);
549 fstr_real_len = fstr.len;
552 if (file->f_version == 0) {
554 * The file was seek'ed, which means that @file->private_data
555 * is now invalid. This may also be just the first
556 * 'ubifs_readdir()' invocation, in which case
557 * @file->private_data is NULL, and the below code is
560 kfree(file->private_data);
561 file->private_data = NULL;
565 * 'generic_file_llseek()' unconditionally sets @file->f_version to
566 * zero, and we use this for detecting whether the file was seek'ed.
570 /* File positions 0 and 1 correspond to "." and ".." */
572 ubifs_assert(!file->private_data);
573 if (!dir_emit_dots(file, ctx)) {
575 fscrypt_fname_free_buffer(&fstr);
579 /* Find the first entry in TNC and save it */
580 lowest_dent_key(c, &key, dir->i_ino);
582 dent = ubifs_tnc_next_ent(c, &key, &nm);
588 ctx->pos = key_hash_flash(c, &dent->key);
589 file->private_data = dent;
592 dent = file->private_data;
595 * The directory was seek'ed to and is now readdir'ed.
596 * Find the entry corresponding to @ctx->pos or the closest one.
598 dent_key_init_hash(c, &key, dir->i_ino, ctx->pos);
600 dent = ubifs_tnc_next_ent(c, &key, &nm);
605 ctx->pos = key_hash_flash(c, &dent->key);
606 file->private_data = dent;
610 dbg_gen("ino %llu, new f_pos %#x",
611 (unsigned long long)le64_to_cpu(dent->inum),
612 key_hash_flash(c, &dent->key));
613 ubifs_assert(le64_to_cpu(dent->ch.sqnum) >
614 ubifs_inode(dir)->creat_sqnum);
616 fname_len(&nm) = le16_to_cpu(dent->nlen);
617 fname_name(&nm) = dent->name;
620 fstr.len = fstr_real_len;
622 err = fscrypt_fname_disk_to_usr(dir, key_hash_flash(c,
624 le32_to_cpu(dent->cookie),
625 &nm.disk_name, &fstr);
629 fstr.len = fname_len(&nm);
630 fstr.name = fname_name(&nm);
633 if (!dir_emit(ctx, fstr.name, fstr.len,
634 le64_to_cpu(dent->inum),
635 vfs_dent_type(dent->type))) {
637 fscrypt_fname_free_buffer(&fstr);
641 /* Switch to the next entry */
642 key_read(c, &dent->key, &key);
643 dent = ubifs_tnc_next_ent(c, &key, &nm);
649 kfree(file->private_data);
650 ctx->pos = key_hash_flash(c, &dent->key);
651 file->private_data = dent;
656 kfree(file->private_data);
657 file->private_data = NULL;
660 fscrypt_fname_free_buffer(&fstr);
663 ubifs_err(c, "cannot find next direntry, error %d", err);
666 * -ENOENT is a non-fatal error in this context, the TNC uses
667 * it to indicate that the cursor moved past the current directory
668 * and readdir() has to stop.
673 /* 2 is a special value indicating that there are no more direntries */
678 /* Free saved readdir() state when the directory is closed */
679 static int ubifs_dir_release(struct inode *dir, struct file *file)
681 kfree(file->private_data);
682 file->private_data = NULL;
687 * lock_2_inodes - a wrapper for locking two UBIFS inodes.
688 * @inode1: first inode
689 * @inode2: second inode
691 * We do not implement any tricks to guarantee strict lock ordering, because
692 * VFS has already done it for us on the @i_mutex. So this is just a simple
695 static void lock_2_inodes(struct inode *inode1, struct inode *inode2)
697 mutex_lock_nested(&ubifs_inode(inode1)->ui_mutex, WB_MUTEX_1);
698 mutex_lock_nested(&ubifs_inode(inode2)->ui_mutex, WB_MUTEX_2);
702 * unlock_2_inodes - a wrapper for unlocking two UBIFS inodes.
703 * @inode1: first inode
704 * @inode2: second inode
706 static void unlock_2_inodes(struct inode *inode1, struct inode *inode2)
708 mutex_unlock(&ubifs_inode(inode2)->ui_mutex);
709 mutex_unlock(&ubifs_inode(inode1)->ui_mutex);
712 static int ubifs_link(struct dentry *old_dentry, struct inode *dir,
713 struct dentry *dentry)
715 struct ubifs_info *c = dir->i_sb->s_fs_info;
716 struct inode *inode = d_inode(old_dentry);
717 struct ubifs_inode *ui = ubifs_inode(inode);
718 struct ubifs_inode *dir_ui = ubifs_inode(dir);
719 int err, sz_change = CALC_DENT_SIZE(dentry->d_name.len);
720 struct ubifs_budget_req req = { .new_dent = 1, .dirtied_ino = 2,
721 .dirtied_ino_d = ALIGN(ui->data_len, 8) };
722 struct fscrypt_name nm;
725 * Budget request settings: new direntry, changing the target inode,
726 * changing the parent inode.
729 dbg_gen("dent '%pd' to ino %lu (nlink %d) in dir ino %lu",
730 dentry, inode->i_ino,
731 inode->i_nlink, dir->i_ino);
732 ubifs_assert(inode_is_locked(dir));
733 ubifs_assert(inode_is_locked(inode));
735 err = fscrypt_prepare_link(old_dentry, dir, dentry);
739 err = fscrypt_setup_filename(dir, &dentry->d_name, 0, &nm);
743 err = dbg_check_synced_i_size(c, inode);
747 err = ubifs_budget_space(c, &req);
751 lock_2_inodes(dir, inode);
753 /* Handle O_TMPFILE corner case, it is allowed to link a O_TMPFILE. */
754 if (inode->i_nlink == 0)
755 ubifs_delete_orphan(c, inode->i_ino);
759 inode->i_ctime = current_time(inode);
760 dir->i_size += sz_change;
761 dir_ui->ui_size = dir->i_size;
762 dir->i_mtime = dir->i_ctime = inode->i_ctime;
763 err = ubifs_jnl_update(c, dir, &nm, inode, 0, 0);
766 unlock_2_inodes(dir, inode);
768 ubifs_release_budget(c, &req);
769 d_instantiate(dentry, inode);
770 fscrypt_free_filename(&nm);
774 dir->i_size -= sz_change;
775 dir_ui->ui_size = dir->i_size;
777 if (inode->i_nlink == 0)
778 ubifs_add_orphan(c, inode->i_ino);
779 unlock_2_inodes(dir, inode);
780 ubifs_release_budget(c, &req);
783 fscrypt_free_filename(&nm);
787 static int ubifs_unlink(struct inode *dir, struct dentry *dentry)
789 struct ubifs_info *c = dir->i_sb->s_fs_info;
790 struct inode *inode = d_inode(dentry);
791 struct ubifs_inode *dir_ui = ubifs_inode(dir);
792 int err, sz_change, budgeted = 1;
793 struct ubifs_budget_req req = { .mod_dent = 1, .dirtied_ino = 2 };
794 unsigned int saved_nlink = inode->i_nlink;
795 struct fscrypt_name nm;
798 * Budget request settings: deletion direntry, deletion inode (+1 for
799 * @dirtied_ino), changing the parent directory inode. If budgeting
800 * fails, go ahead anyway because we have extra space reserved for
804 dbg_gen("dent '%pd' from ino %lu (nlink %d) in dir ino %lu",
805 dentry, inode->i_ino,
806 inode->i_nlink, dir->i_ino);
808 if (ubifs_crypt_is_encrypted(dir)) {
809 err = fscrypt_get_encryption_info(dir);
810 if (err && err != -ENOKEY)
814 err = fscrypt_setup_filename(dir, &dentry->d_name, 1, &nm);
818 sz_change = CALC_DENT_SIZE(fname_len(&nm));
820 ubifs_assert(inode_is_locked(dir));
821 ubifs_assert(inode_is_locked(inode));
822 err = dbg_check_synced_i_size(c, inode);
826 err = ubifs_budget_space(c, &req);
833 lock_2_inodes(dir, inode);
834 inode->i_ctime = current_time(dir);
836 dir->i_size -= sz_change;
837 dir_ui->ui_size = dir->i_size;
838 dir->i_mtime = dir->i_ctime = inode->i_ctime;
839 err = ubifs_jnl_update(c, dir, &nm, inode, 1, 0);
842 unlock_2_inodes(dir, inode);
845 ubifs_release_budget(c, &req);
847 /* We've deleted something - clean the "no space" flags */
848 c->bi.nospace = c->bi.nospace_rp = 0;
851 fscrypt_free_filename(&nm);
855 dir->i_size += sz_change;
856 dir_ui->ui_size = dir->i_size;
857 set_nlink(inode, saved_nlink);
858 unlock_2_inodes(dir, inode);
860 ubifs_release_budget(c, &req);
862 fscrypt_free_filename(&nm);
867 * check_dir_empty - check if a directory is empty or not.
868 * @dir: VFS inode object of the directory to check
870 * This function checks if directory @dir is empty. Returns zero if the
871 * directory is empty, %-ENOTEMPTY if it is not, and other negative error codes
872 * in case of of errors.
874 int ubifs_check_dir_empty(struct inode *dir)
876 struct ubifs_info *c = dir->i_sb->s_fs_info;
877 struct fscrypt_name nm = { 0 };
878 struct ubifs_dent_node *dent;
882 lowest_dent_key(c, &key, dir->i_ino);
883 dent = ubifs_tnc_next_ent(c, &key, &nm);
895 static int ubifs_rmdir(struct inode *dir, struct dentry *dentry)
897 struct ubifs_info *c = dir->i_sb->s_fs_info;
898 struct inode *inode = d_inode(dentry);
899 int err, sz_change, budgeted = 1;
900 struct ubifs_inode *dir_ui = ubifs_inode(dir);
901 struct ubifs_budget_req req = { .mod_dent = 1, .dirtied_ino = 2 };
902 struct fscrypt_name nm;
905 * Budget request settings: deletion direntry, deletion inode and
906 * changing the parent inode. If budgeting fails, go ahead anyway
907 * because we have extra space reserved for deletions.
910 dbg_gen("directory '%pd', ino %lu in dir ino %lu", dentry,
911 inode->i_ino, dir->i_ino);
912 ubifs_assert(inode_is_locked(dir));
913 ubifs_assert(inode_is_locked(inode));
914 err = ubifs_check_dir_empty(d_inode(dentry));
918 if (ubifs_crypt_is_encrypted(dir)) {
919 err = fscrypt_get_encryption_info(dir);
920 if (err && err != -ENOKEY)
924 err = fscrypt_setup_filename(dir, &dentry->d_name, 1, &nm);
928 sz_change = CALC_DENT_SIZE(fname_len(&nm));
930 err = ubifs_budget_space(c, &req);
937 lock_2_inodes(dir, inode);
938 inode->i_ctime = current_time(dir);
941 dir->i_size -= sz_change;
942 dir_ui->ui_size = dir->i_size;
943 dir->i_mtime = dir->i_ctime = inode->i_ctime;
944 err = ubifs_jnl_update(c, dir, &nm, inode, 1, 0);
947 unlock_2_inodes(dir, inode);
950 ubifs_release_budget(c, &req);
952 /* We've deleted something - clean the "no space" flags */
953 c->bi.nospace = c->bi.nospace_rp = 0;
956 fscrypt_free_filename(&nm);
960 dir->i_size += sz_change;
961 dir_ui->ui_size = dir->i_size;
964 unlock_2_inodes(dir, inode);
966 ubifs_release_budget(c, &req);
968 fscrypt_free_filename(&nm);
972 static int ubifs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
975 struct ubifs_inode *dir_ui = ubifs_inode(dir);
976 struct ubifs_info *c = dir->i_sb->s_fs_info;
978 struct ubifs_budget_req req = { .new_ino = 1, .new_dent = 1 };
979 struct fscrypt_name nm;
982 * Budget request settings: new inode, new direntry and changing parent
986 dbg_gen("dent '%pd', mode %#hx in dir ino %lu",
987 dentry, mode, dir->i_ino);
989 err = ubifs_budget_space(c, &req);
993 err = fscrypt_setup_filename(dir, &dentry->d_name, 0, &nm);
997 sz_change = CALC_DENT_SIZE(fname_len(&nm));
999 inode = ubifs_new_inode(c, dir, S_IFDIR | mode);
1000 if (IS_ERR(inode)) {
1001 err = PTR_ERR(inode);
1005 err = ubifs_init_security(dir, inode, &dentry->d_name);
1009 mutex_lock(&dir_ui->ui_mutex);
1010 insert_inode_hash(inode);
1013 dir->i_size += sz_change;
1014 dir_ui->ui_size = dir->i_size;
1015 dir->i_mtime = dir->i_ctime = inode->i_ctime;
1016 err = ubifs_jnl_update(c, dir, &nm, inode, 0, 0);
1018 ubifs_err(c, "cannot create directory, error %d", err);
1021 mutex_unlock(&dir_ui->ui_mutex);
1023 ubifs_release_budget(c, &req);
1024 d_instantiate(dentry, inode);
1025 fscrypt_free_filename(&nm);
1029 dir->i_size -= sz_change;
1030 dir_ui->ui_size = dir->i_size;
1032 mutex_unlock(&dir_ui->ui_mutex);
1034 make_bad_inode(inode);
1037 fscrypt_free_filename(&nm);
1039 ubifs_release_budget(c, &req);
1043 static int ubifs_mknod(struct inode *dir, struct dentry *dentry,
1044 umode_t mode, dev_t rdev)
1046 struct inode *inode;
1047 struct ubifs_inode *ui;
1048 struct ubifs_inode *dir_ui = ubifs_inode(dir);
1049 struct ubifs_info *c = dir->i_sb->s_fs_info;
1050 union ubifs_dev_desc *dev = NULL;
1052 int err, devlen = 0;
1053 struct ubifs_budget_req req = { .new_ino = 1, .new_dent = 1,
1055 struct fscrypt_name nm;
1058 * Budget request settings: new inode, new direntry and changing parent
1062 dbg_gen("dent '%pd' in dir ino %lu", dentry, dir->i_ino);
1064 if (S_ISBLK(mode) || S_ISCHR(mode)) {
1065 dev = kmalloc(sizeof(union ubifs_dev_desc), GFP_NOFS);
1068 devlen = ubifs_encode_dev(dev, rdev);
1071 req.new_ino_d = ALIGN(devlen, 8);
1072 err = ubifs_budget_space(c, &req);
1078 err = fscrypt_setup_filename(dir, &dentry->d_name, 0, &nm);
1084 sz_change = CALC_DENT_SIZE(fname_len(&nm));
1086 inode = ubifs_new_inode(c, dir, mode);
1087 if (IS_ERR(inode)) {
1089 err = PTR_ERR(inode);
1093 init_special_inode(inode, inode->i_mode, rdev);
1094 inode->i_size = ubifs_inode(inode)->ui_size = devlen;
1095 ui = ubifs_inode(inode);
1097 ui->data_len = devlen;
1099 err = ubifs_init_security(dir, inode, &dentry->d_name);
1103 mutex_lock(&dir_ui->ui_mutex);
1104 dir->i_size += sz_change;
1105 dir_ui->ui_size = dir->i_size;
1106 dir->i_mtime = dir->i_ctime = inode->i_ctime;
1107 err = ubifs_jnl_update(c, dir, &nm, inode, 0, 0);
1110 mutex_unlock(&dir_ui->ui_mutex);
1112 ubifs_release_budget(c, &req);
1113 insert_inode_hash(inode);
1114 d_instantiate(dentry, inode);
1115 fscrypt_free_filename(&nm);
1119 dir->i_size -= sz_change;
1120 dir_ui->ui_size = dir->i_size;
1121 mutex_unlock(&dir_ui->ui_mutex);
1123 make_bad_inode(inode);
1126 fscrypt_free_filename(&nm);
1128 ubifs_release_budget(c, &req);
1132 static int ubifs_symlink(struct inode *dir, struct dentry *dentry,
1133 const char *symname)
1135 struct inode *inode;
1136 struct ubifs_inode *ui;
1137 struct ubifs_inode *dir_ui = ubifs_inode(dir);
1138 struct ubifs_info *c = dir->i_sb->s_fs_info;
1139 int err, len = strlen(symname);
1140 int sz_change = CALC_DENT_SIZE(len);
1141 struct fscrypt_str disk_link = FSTR_INIT((char *)symname, len + 1);
1142 struct fscrypt_symlink_data *sd = NULL;
1143 struct ubifs_budget_req req = { .new_ino = 1, .new_dent = 1,
1144 .new_ino_d = ALIGN(len, 8),
1146 struct fscrypt_name nm;
1148 if (ubifs_crypt_is_encrypted(dir)) {
1149 err = fscrypt_get_encryption_info(dir);
1153 if (!fscrypt_has_encryption_key(dir)) {
1158 disk_link.len = (fscrypt_fname_encrypted_size(dir, len) +
1159 sizeof(struct fscrypt_symlink_data));
1163 * Budget request settings: new inode, new direntry and changing parent
1167 dbg_gen("dent '%pd', target '%s' in dir ino %lu", dentry,
1168 symname, dir->i_ino);
1170 if (disk_link.len > UBIFS_MAX_INO_DATA)
1171 return -ENAMETOOLONG;
1173 err = ubifs_budget_space(c, &req);
1177 err = fscrypt_setup_filename(dir, &dentry->d_name, 0, &nm);
1181 inode = ubifs_new_inode(c, dir, S_IFLNK | S_IRWXUGO);
1182 if (IS_ERR(inode)) {
1183 err = PTR_ERR(inode);
1187 ui = ubifs_inode(inode);
1188 ui->data = kmalloc(disk_link.len, GFP_NOFS);
1194 if (ubifs_crypt_is_encrypted(dir)) {
1195 struct qstr istr = QSTR_INIT(symname, len);
1196 struct fscrypt_str ostr;
1198 sd = kzalloc(disk_link.len, GFP_NOFS);
1204 ostr.name = sd->encrypted_path;
1205 ostr.len = disk_link.len;
1207 err = fscrypt_fname_usr_to_disk(inode, &istr, &ostr);
1213 sd->len = cpu_to_le16(ostr.len);
1214 disk_link.name = (char *)sd;
1216 inode->i_link = ui->data;
1219 memcpy(ui->data, disk_link.name, disk_link.len);
1220 ((char *)ui->data)[disk_link.len - 1] = '\0';
1223 * The terminating zero byte is not written to the flash media and it
1224 * is put just to make later in-memory string processing simpler. Thus,
1225 * data length is @len, not @len + %1.
1227 ui->data_len = disk_link.len - 1;
1228 inode->i_size = ubifs_inode(inode)->ui_size = disk_link.len - 1;
1230 err = ubifs_init_security(dir, inode, &dentry->d_name);
1234 mutex_lock(&dir_ui->ui_mutex);
1235 dir->i_size += sz_change;
1236 dir_ui->ui_size = dir->i_size;
1237 dir->i_mtime = dir->i_ctime = inode->i_ctime;
1238 err = ubifs_jnl_update(c, dir, &nm, inode, 0, 0);
1241 mutex_unlock(&dir_ui->ui_mutex);
1243 ubifs_release_budget(c, &req);
1244 insert_inode_hash(inode);
1245 d_instantiate(dentry, inode);
1246 fscrypt_free_filename(&nm);
1250 dir->i_size -= sz_change;
1251 dir_ui->ui_size = dir->i_size;
1252 mutex_unlock(&dir_ui->ui_mutex);
1254 make_bad_inode(inode);
1257 fscrypt_free_filename(&nm);
1259 ubifs_release_budget(c, &req);
1264 * lock_4_inodes - a wrapper for locking three UBIFS inodes.
1265 * @inode1: first inode
1266 * @inode2: second inode
1267 * @inode3: third inode
1268 * @inode4: fouth inode
1270 * This function is used for 'ubifs_rename()' and @inode1 may be the same as
1271 * @inode2 whereas @inode3 and @inode4 may be %NULL.
1273 * We do not implement any tricks to guarantee strict lock ordering, because
1274 * VFS has already done it for us on the @i_mutex. So this is just a simple
1277 static void lock_4_inodes(struct inode *inode1, struct inode *inode2,
1278 struct inode *inode3, struct inode *inode4)
1280 mutex_lock_nested(&ubifs_inode(inode1)->ui_mutex, WB_MUTEX_1);
1281 if (inode2 != inode1)
1282 mutex_lock_nested(&ubifs_inode(inode2)->ui_mutex, WB_MUTEX_2);
1284 mutex_lock_nested(&ubifs_inode(inode3)->ui_mutex, WB_MUTEX_3);
1286 mutex_lock_nested(&ubifs_inode(inode4)->ui_mutex, WB_MUTEX_4);
1290 * unlock_4_inodes - a wrapper for unlocking three UBIFS inodes for rename.
1291 * @inode1: first inode
1292 * @inode2: second inode
1293 * @inode3: third inode
1294 * @inode4: fouth inode
1296 static void unlock_4_inodes(struct inode *inode1, struct inode *inode2,
1297 struct inode *inode3, struct inode *inode4)
1300 mutex_unlock(&ubifs_inode(inode4)->ui_mutex);
1302 mutex_unlock(&ubifs_inode(inode3)->ui_mutex);
1303 if (inode1 != inode2)
1304 mutex_unlock(&ubifs_inode(inode2)->ui_mutex);
1305 mutex_unlock(&ubifs_inode(inode1)->ui_mutex);
1308 static int do_rename(struct inode *old_dir, struct dentry *old_dentry,
1309 struct inode *new_dir, struct dentry *new_dentry,
1312 struct ubifs_info *c = old_dir->i_sb->s_fs_info;
1313 struct inode *old_inode = d_inode(old_dentry);
1314 struct inode *new_inode = d_inode(new_dentry);
1315 struct inode *whiteout = NULL;
1316 struct ubifs_inode *old_inode_ui = ubifs_inode(old_inode);
1317 struct ubifs_inode *whiteout_ui = NULL;
1318 int err, release, sync = 0, move = (new_dir != old_dir);
1319 int is_dir = S_ISDIR(old_inode->i_mode);
1320 int unlink = !!new_inode, new_sz, old_sz;
1321 struct ubifs_budget_req req = { .new_dent = 1, .mod_dent = 1,
1323 struct ubifs_budget_req ino_req = { .dirtied_ino = 1,
1324 .dirtied_ino_d = ALIGN(old_inode_ui->data_len, 8) };
1325 struct timespec time;
1326 unsigned int uninitialized_var(saved_nlink);
1327 struct fscrypt_name old_nm, new_nm;
1330 * Budget request settings: deletion direntry, new direntry, removing
1331 * the old inode, and changing old and new parent directory inodes.
1333 * However, this operation also marks the target inode as dirty and
1334 * does not write it, so we allocate budget for the target inode
1338 dbg_gen("dent '%pd' ino %lu in dir ino %lu to dent '%pd' in dir ino %lu flags 0x%x",
1339 old_dentry, old_inode->i_ino, old_dir->i_ino,
1340 new_dentry, new_dir->i_ino, flags);
1343 ubifs_assert(inode_is_locked(new_inode));
1345 if (unlink && is_dir) {
1346 err = ubifs_check_dir_empty(new_inode);
1351 err = fscrypt_setup_filename(old_dir, &old_dentry->d_name, 0, &old_nm);
1355 err = fscrypt_setup_filename(new_dir, &new_dentry->d_name, 0, &new_nm);
1357 fscrypt_free_filename(&old_nm);
1361 new_sz = CALC_DENT_SIZE(fname_len(&new_nm));
1362 old_sz = CALC_DENT_SIZE(fname_len(&old_nm));
1364 err = ubifs_budget_space(c, &req);
1366 fscrypt_free_filename(&old_nm);
1367 fscrypt_free_filename(&new_nm);
1370 err = ubifs_budget_space(c, &ino_req);
1372 fscrypt_free_filename(&old_nm);
1373 fscrypt_free_filename(&new_nm);
1374 ubifs_release_budget(c, &req);
1378 if (flags & RENAME_WHITEOUT) {
1379 union ubifs_dev_desc *dev = NULL;
1381 dev = kmalloc(sizeof(union ubifs_dev_desc), GFP_NOFS);
1387 err = do_tmpfile(old_dir, old_dentry, S_IFCHR | WHITEOUT_MODE, &whiteout);
1393 whiteout->i_state |= I_LINKABLE;
1394 whiteout_ui = ubifs_inode(whiteout);
1395 whiteout_ui->data = dev;
1396 whiteout_ui->data_len = ubifs_encode_dev(dev, MKDEV(0, 0));
1397 ubifs_assert(!whiteout_ui->dirty);
1400 lock_4_inodes(old_dir, new_dir, new_inode, whiteout);
1403 * Like most other Unix systems, set the @i_ctime for inodes on a
1406 time = current_time(old_dir);
1407 old_inode->i_ctime = time;
1409 /* We must adjust parent link count when renaming directories */
1413 * @old_dir loses a link because we are moving
1414 * @old_inode to a different directory.
1416 drop_nlink(old_dir);
1418 * @new_dir only gains a link if we are not also
1419 * overwriting an existing directory.
1425 * @old_inode is not moving to a different directory,
1426 * but @old_dir still loses a link if we are
1427 * overwriting an existing directory.
1430 drop_nlink(old_dir);
1434 old_dir->i_size -= old_sz;
1435 ubifs_inode(old_dir)->ui_size = old_dir->i_size;
1436 old_dir->i_mtime = old_dir->i_ctime = time;
1437 new_dir->i_mtime = new_dir->i_ctime = time;
1440 * And finally, if we unlinked a direntry which happened to have the
1441 * same name as the moved direntry, we have to decrement @i_nlink of
1442 * the unlinked inode and change its ctime.
1446 * Directories cannot have hard-links, so if this is a
1447 * directory, just clear @i_nlink.
1449 saved_nlink = new_inode->i_nlink;
1451 clear_nlink(new_inode);
1453 drop_nlink(new_inode);
1454 new_inode->i_ctime = time;
1456 new_dir->i_size += new_sz;
1457 ubifs_inode(new_dir)->ui_size = new_dir->i_size;
1461 * Do not ask 'ubifs_jnl_rename()' to flush write-buffer if @old_inode
1462 * is dirty, because this will be done later on at the end of
1465 if (IS_SYNC(old_inode)) {
1466 sync = IS_DIRSYNC(old_dir) || IS_DIRSYNC(new_dir);
1467 if (unlink && IS_SYNC(new_inode))
1472 struct ubifs_budget_req wht_req = { .dirtied_ino = 1,
1474 ALIGN(ubifs_inode(whiteout)->data_len, 8) };
1476 err = ubifs_budget_space(c, &wht_req);
1478 kfree(whiteout_ui->data);
1479 whiteout_ui->data_len = 0;
1484 inc_nlink(whiteout);
1485 mark_inode_dirty(whiteout);
1486 whiteout->i_state &= ~I_LINKABLE;
1490 err = ubifs_jnl_rename(c, old_dir, old_inode, &old_nm, new_dir,
1491 new_inode, &new_nm, whiteout, sync);
1495 unlock_4_inodes(old_dir, new_dir, new_inode, whiteout);
1496 ubifs_release_budget(c, &req);
1498 mutex_lock(&old_inode_ui->ui_mutex);
1499 release = old_inode_ui->dirty;
1500 mark_inode_dirty_sync(old_inode);
1501 mutex_unlock(&old_inode_ui->ui_mutex);
1504 ubifs_release_budget(c, &ino_req);
1505 if (IS_SYNC(old_inode))
1506 err = old_inode->i_sb->s_op->write_inode(old_inode, NULL);
1508 fscrypt_free_filename(&old_nm);
1509 fscrypt_free_filename(&new_nm);
1514 set_nlink(new_inode, saved_nlink);
1516 new_dir->i_size -= new_sz;
1517 ubifs_inode(new_dir)->ui_size = new_dir->i_size;
1519 old_dir->i_size += old_sz;
1520 ubifs_inode(old_dir)->ui_size = old_dir->i_size;
1525 drop_nlink(new_dir);
1532 drop_nlink(whiteout);
1535 unlock_4_inodes(old_dir, new_dir, new_inode, whiteout);
1537 ubifs_release_budget(c, &ino_req);
1538 ubifs_release_budget(c, &req);
1539 fscrypt_free_filename(&old_nm);
1540 fscrypt_free_filename(&new_nm);
1544 static int ubifs_xrename(struct inode *old_dir, struct dentry *old_dentry,
1545 struct inode *new_dir, struct dentry *new_dentry)
1547 struct ubifs_info *c = old_dir->i_sb->s_fs_info;
1548 struct ubifs_budget_req req = { .new_dent = 1, .mod_dent = 1,
1550 int sync = IS_DIRSYNC(old_dir) || IS_DIRSYNC(new_dir);
1551 struct inode *fst_inode = d_inode(old_dentry);
1552 struct inode *snd_inode = d_inode(new_dentry);
1553 struct timespec time;
1555 struct fscrypt_name fst_nm, snd_nm;
1557 ubifs_assert(fst_inode && snd_inode);
1559 err = fscrypt_setup_filename(old_dir, &old_dentry->d_name, 0, &fst_nm);
1563 err = fscrypt_setup_filename(new_dir, &new_dentry->d_name, 0, &snd_nm);
1565 fscrypt_free_filename(&fst_nm);
1569 lock_4_inodes(old_dir, new_dir, NULL, NULL);
1571 time = current_time(old_dir);
1572 fst_inode->i_ctime = time;
1573 snd_inode->i_ctime = time;
1574 old_dir->i_mtime = old_dir->i_ctime = time;
1575 new_dir->i_mtime = new_dir->i_ctime = time;
1577 if (old_dir != new_dir) {
1578 if (S_ISDIR(fst_inode->i_mode) && !S_ISDIR(snd_inode->i_mode)) {
1580 drop_nlink(old_dir);
1582 else if (!S_ISDIR(fst_inode->i_mode) && S_ISDIR(snd_inode->i_mode)) {
1583 drop_nlink(new_dir);
1588 err = ubifs_jnl_xrename(c, old_dir, fst_inode, &fst_nm, new_dir,
1589 snd_inode, &snd_nm, sync);
1591 unlock_4_inodes(old_dir, new_dir, NULL, NULL);
1592 ubifs_release_budget(c, &req);
1594 fscrypt_free_filename(&fst_nm);
1595 fscrypt_free_filename(&snd_nm);
1599 static int ubifs_rename(struct inode *old_dir, struct dentry *old_dentry,
1600 struct inode *new_dir, struct dentry *new_dentry,
1605 if (flags & ~(RENAME_NOREPLACE | RENAME_WHITEOUT | RENAME_EXCHANGE))
1608 ubifs_assert(inode_is_locked(old_dir));
1609 ubifs_assert(inode_is_locked(new_dir));
1611 err = fscrypt_prepare_rename(old_dir, old_dentry, new_dir, new_dentry,
1616 if (flags & RENAME_EXCHANGE)
1617 return ubifs_xrename(old_dir, old_dentry, new_dir, new_dentry);
1619 return do_rename(old_dir, old_dentry, new_dir, new_dentry, flags);
1622 int ubifs_getattr(const struct path *path, struct kstat *stat,
1623 u32 request_mask, unsigned int flags)
1626 struct inode *inode = d_inode(path->dentry);
1627 struct ubifs_inode *ui = ubifs_inode(inode);
1629 mutex_lock(&ui->ui_mutex);
1631 if (ui->flags & UBIFS_APPEND_FL)
1632 stat->attributes |= STATX_ATTR_APPEND;
1633 if (ui->flags & UBIFS_COMPR_FL)
1634 stat->attributes |= STATX_ATTR_COMPRESSED;
1635 if (ui->flags & UBIFS_CRYPT_FL)
1636 stat->attributes |= STATX_ATTR_ENCRYPTED;
1637 if (ui->flags & UBIFS_IMMUTABLE_FL)
1638 stat->attributes |= STATX_ATTR_IMMUTABLE;
1640 stat->attributes_mask |= (STATX_ATTR_APPEND |
1641 STATX_ATTR_COMPRESSED |
1642 STATX_ATTR_ENCRYPTED |
1643 STATX_ATTR_IMMUTABLE);
1645 generic_fillattr(inode, stat);
1646 stat->blksize = UBIFS_BLOCK_SIZE;
1647 stat->size = ui->ui_size;
1650 * Unfortunately, the 'stat()' system call was designed for block
1651 * device based file systems, and it is not appropriate for UBIFS,
1652 * because UBIFS does not have notion of "block". For example, it is
1653 * difficult to tell how many block a directory takes - it actually
1654 * takes less than 300 bytes, but we have to round it to block size,
1655 * which introduces large mistake. This makes utilities like 'du' to
1656 * report completely senseless numbers. This is the reason why UBIFS
1657 * goes the same way as JFFS2 - it reports zero blocks for everything
1658 * but regular files, which makes more sense than reporting completely
1661 if (S_ISREG(inode->i_mode)) {
1662 size = ui->xattr_size;
1664 size = ALIGN(size, UBIFS_BLOCK_SIZE);
1666 * Note, user-space expects 512-byte blocks count irrespectively
1667 * of what was reported in @stat->size.
1669 stat->blocks = size >> 9;
1672 mutex_unlock(&ui->ui_mutex);
1676 static int ubifs_dir_open(struct inode *dir, struct file *file)
1678 if (ubifs_crypt_is_encrypted(dir))
1679 return fscrypt_get_encryption_info(dir) ? -EACCES : 0;
1684 const struct inode_operations ubifs_dir_inode_operations = {
1685 .lookup = ubifs_lookup,
1686 .create = ubifs_create,
1688 .symlink = ubifs_symlink,
1689 .unlink = ubifs_unlink,
1690 .mkdir = ubifs_mkdir,
1691 .rmdir = ubifs_rmdir,
1692 .mknod = ubifs_mknod,
1693 .rename = ubifs_rename,
1694 .setattr = ubifs_setattr,
1695 .getattr = ubifs_getattr,
1696 .listxattr = ubifs_listxattr,
1697 #ifdef CONFIG_UBIFS_ATIME_SUPPORT
1698 .update_time = ubifs_update_time,
1700 .tmpfile = ubifs_tmpfile,
1703 const struct file_operations ubifs_dir_operations = {
1704 .llseek = generic_file_llseek,
1705 .release = ubifs_dir_release,
1706 .read = generic_read_dir,
1707 .iterate_shared = ubifs_readdir,
1708 .fsync = ubifs_fsync,
1709 .unlocked_ioctl = ubifs_ioctl,
1710 .open = ubifs_dir_open,
1711 #ifdef CONFIG_COMPAT
1712 .compat_ioctl = ubifs_compat_ioctl,