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 = NULL;
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, &nm);
225 return d_splice_alias(NULL, dentry);
229 if (fname_len(&nm) > UBIFS_MAX_NLEN) {
230 inode = ERR_PTR(-ENAMETOOLONG);
234 dent = kmalloc(UBIFS_MAX_DENT_NODE_SZ, GFP_NOFS);
236 inode = ERR_PTR(-ENOMEM);
241 ubifs_assert(c, fname_len(&nm) == 0);
242 ubifs_assert(c, fname_name(&nm) == NULL);
243 if (nm.hash & ~UBIFS_S_KEY_HASH_MASK)
244 goto done; /* ENOENT */
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);
254 dbg_gen("not found");
256 inode = ERR_PTR(err);
260 if (dbg_check_name(c, dent, &nm)) {
261 inode = ERR_PTR(-EINVAL);
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);
284 inode = ERR_PTR(-EPERM);
289 fscrypt_free_filename(&nm);
290 return d_splice_alias(inode, dentry);
293 static int ubifs_prepare_create(struct inode *dir, struct dentry *dentry,
294 struct fscrypt_name *nm)
296 if (fscrypt_is_nokey_name(dentry))
299 return fscrypt_setup_filename(dir, &dentry->d_name, 0, nm);
302 static int ubifs_create(struct inode *dir, struct dentry *dentry, umode_t mode,
306 struct ubifs_info *c = dir->i_sb->s_fs_info;
307 struct ubifs_budget_req req = { .new_ino = 1, .new_dent = 1,
309 struct ubifs_inode *dir_ui = ubifs_inode(dir);
310 struct fscrypt_name nm;
314 * Budget request settings: new inode, new direntry, changing the
315 * parent directory inode.
318 dbg_gen("dent '%pd', mode %#hx in dir ino %lu",
319 dentry, mode, dir->i_ino);
321 err = ubifs_budget_space(c, &req);
325 err = ubifs_prepare_create(dir, dentry, &nm);
329 sz_change = CALC_DENT_SIZE(fname_len(&nm));
331 inode = ubifs_new_inode(c, dir, mode);
333 err = PTR_ERR(inode);
337 err = ubifs_init_security(dir, inode, &dentry->d_name);
341 mutex_lock(&dir_ui->ui_mutex);
342 dir->i_size += sz_change;
343 dir_ui->ui_size = dir->i_size;
344 dir->i_mtime = dir->i_ctime = inode->i_ctime;
345 err = ubifs_jnl_update(c, dir, &nm, inode, 0, 0);
348 mutex_unlock(&dir_ui->ui_mutex);
350 ubifs_release_budget(c, &req);
351 fscrypt_free_filename(&nm);
352 insert_inode_hash(inode);
353 d_instantiate(dentry, inode);
357 dir->i_size -= sz_change;
358 dir_ui->ui_size = dir->i_size;
359 mutex_unlock(&dir_ui->ui_mutex);
361 make_bad_inode(inode);
364 fscrypt_free_filename(&nm);
366 ubifs_release_budget(c, &req);
367 ubifs_err(c, "cannot create regular file, error %d", err);
371 static int do_tmpfile(struct inode *dir, struct dentry *dentry,
372 umode_t mode, struct inode **whiteout)
375 struct ubifs_info *c = dir->i_sb->s_fs_info;
376 struct ubifs_budget_req req = { .new_ino = 1, .new_dent = 1};
377 struct ubifs_budget_req ino_req = { .dirtied_ino = 1 };
378 struct ubifs_inode *ui, *dir_ui = ubifs_inode(dir);
379 int err, instantiated = 0;
380 struct fscrypt_name nm;
383 * Budget request settings: new dirty inode, new direntry,
384 * budget for dirtied inode will be released via writeback.
387 dbg_gen("dent '%pd', mode %#hx in dir ino %lu",
388 dentry, mode, dir->i_ino);
390 err = fscrypt_setup_filename(dir, &dentry->d_name, 0, &nm);
394 err = ubifs_budget_space(c, &req);
396 fscrypt_free_filename(&nm);
400 err = ubifs_budget_space(c, &ino_req);
402 ubifs_release_budget(c, &req);
403 fscrypt_free_filename(&nm);
407 inode = ubifs_new_inode(c, dir, mode);
409 err = PTR_ERR(inode);
412 ui = ubifs_inode(inode);
415 init_special_inode(inode, inode->i_mode, WHITEOUT_DEV);
416 ubifs_assert(c, inode->i_op == &ubifs_file_inode_operations);
419 err = ubifs_init_security(dir, inode, &dentry->d_name);
423 mutex_lock(&ui->ui_mutex);
424 insert_inode_hash(inode);
427 mark_inode_dirty(inode);
431 d_tmpfile(dentry, inode);
433 ubifs_assert(c, ui->dirty);
436 mutex_unlock(&ui->ui_mutex);
438 mutex_lock(&dir_ui->ui_mutex);
439 err = ubifs_jnl_update(c, dir, &nm, inode, 1, 0);
442 mutex_unlock(&dir_ui->ui_mutex);
444 ubifs_release_budget(c, &req);
449 mutex_unlock(&dir_ui->ui_mutex);
451 make_bad_inode(inode);
455 ubifs_release_budget(c, &req);
457 ubifs_release_budget(c, &ino_req);
458 fscrypt_free_filename(&nm);
459 ubifs_err(c, "cannot create temporary file, error %d", err);
463 static int ubifs_tmpfile(struct inode *dir, struct dentry *dentry,
466 return do_tmpfile(dir, dentry, mode, NULL);
470 * vfs_dent_type - get VFS directory entry type.
471 * @type: UBIFS directory entry type
473 * This function converts UBIFS directory entry type into VFS directory entry
476 static unsigned int vfs_dent_type(uint8_t type)
479 case UBIFS_ITYPE_REG:
481 case UBIFS_ITYPE_DIR:
483 case UBIFS_ITYPE_LNK:
485 case UBIFS_ITYPE_BLK:
487 case UBIFS_ITYPE_CHR:
489 case UBIFS_ITYPE_FIFO:
491 case UBIFS_ITYPE_SOCK:
500 * The classical Unix view for directory is that it is a linear array of
501 * (name, inode number) entries. Linux/VFS assumes this model as well.
502 * Particularly, 'readdir()' call wants us to return a directory entry offset
503 * which later may be used to continue 'readdir()'ing the directory or to
504 * 'seek()' to that specific direntry. Obviously UBIFS does not really fit this
505 * model because directory entries are identified by keys, which may collide.
507 * UBIFS uses directory entry hash value for directory offsets, so
508 * 'seekdir()'/'telldir()' may not always work because of possible key
509 * collisions. But UBIFS guarantees that consecutive 'readdir()' calls work
510 * properly by means of saving full directory entry name in the private field
511 * of the file description object.
513 * This means that UBIFS cannot support NFS which requires full
514 * 'seekdir()'/'telldir()' support.
516 static int ubifs_readdir(struct file *file, struct dir_context *ctx)
518 int fstr_real_len = 0, err = 0;
519 struct fscrypt_name nm;
520 struct fscrypt_str fstr = {0};
522 struct ubifs_dent_node *dent;
523 struct inode *dir = file_inode(file);
524 struct ubifs_info *c = dir->i_sb->s_fs_info;
525 bool encrypted = ubifs_crypt_is_encrypted(dir);
527 dbg_gen("dir ino %lu, f_pos %#llx", dir->i_ino, ctx->pos);
529 if (ctx->pos > UBIFS_S_KEY_HASH_MASK || ctx->pos == 2)
531 * The directory was seek'ed to a senseless position or there
532 * are no more entries.
537 err = fscrypt_get_encryption_info(dir);
538 if (err && err != -ENOKEY)
541 err = fscrypt_fname_alloc_buffer(dir, UBIFS_MAX_NLEN, &fstr);
545 fstr_real_len = fstr.len;
548 if (file->f_version == 0) {
550 * The file was seek'ed, which means that @file->private_data
551 * is now invalid. This may also be just the first
552 * 'ubifs_readdir()' invocation, in which case
553 * @file->private_data is NULL, and the below code is
556 kfree(file->private_data);
557 file->private_data = NULL;
561 * 'generic_file_llseek()' unconditionally sets @file->f_version to
562 * zero, and we use this for detecting whether the file was seek'ed.
566 /* File positions 0 and 1 correspond to "." and ".." */
568 ubifs_assert(c, !file->private_data);
569 if (!dir_emit_dots(file, ctx)) {
571 fscrypt_fname_free_buffer(&fstr);
575 /* Find the first entry in TNC and save it */
576 lowest_dent_key(c, &key, dir->i_ino);
578 dent = ubifs_tnc_next_ent(c, &key, &nm);
584 ctx->pos = key_hash_flash(c, &dent->key);
585 file->private_data = dent;
588 dent = file->private_data;
591 * The directory was seek'ed to and is now readdir'ed.
592 * Find the entry corresponding to @ctx->pos or the closest one.
594 dent_key_init_hash(c, &key, dir->i_ino, ctx->pos);
596 dent = ubifs_tnc_next_ent(c, &key, &nm);
601 ctx->pos = key_hash_flash(c, &dent->key);
602 file->private_data = dent;
606 dbg_gen("ino %llu, new f_pos %#x",
607 (unsigned long long)le64_to_cpu(dent->inum),
608 key_hash_flash(c, &dent->key));
609 ubifs_assert(c, le64_to_cpu(dent->ch.sqnum) >
610 ubifs_inode(dir)->creat_sqnum);
612 fname_len(&nm) = le16_to_cpu(dent->nlen);
613 fname_name(&nm) = dent->name;
616 fstr.len = fstr_real_len;
618 err = fscrypt_fname_disk_to_usr(dir, key_hash_flash(c,
620 le32_to_cpu(dent->cookie),
621 &nm.disk_name, &fstr);
625 fstr.len = fname_len(&nm);
626 fstr.name = fname_name(&nm);
629 if (!dir_emit(ctx, fstr.name, fstr.len,
630 le64_to_cpu(dent->inum),
631 vfs_dent_type(dent->type))) {
633 fscrypt_fname_free_buffer(&fstr);
637 /* Switch to the next entry */
638 key_read(c, &dent->key, &key);
639 dent = ubifs_tnc_next_ent(c, &key, &nm);
645 kfree(file->private_data);
646 ctx->pos = key_hash_flash(c, &dent->key);
647 file->private_data = dent;
652 kfree(file->private_data);
653 file->private_data = NULL;
656 fscrypt_fname_free_buffer(&fstr);
659 ubifs_err(c, "cannot find next direntry, error %d", err);
662 * -ENOENT is a non-fatal error in this context, the TNC uses
663 * it to indicate that the cursor moved past the current directory
664 * and readdir() has to stop.
669 /* 2 is a special value indicating that there are no more direntries */
674 /* Free saved readdir() state when the directory is closed */
675 static int ubifs_dir_release(struct inode *dir, struct file *file)
677 kfree(file->private_data);
678 file->private_data = NULL;
683 * lock_2_inodes - a wrapper for locking two UBIFS inodes.
684 * @inode1: first inode
685 * @inode2: second inode
687 * We do not implement any tricks to guarantee strict lock ordering, because
688 * VFS has already done it for us on the @i_mutex. So this is just a simple
691 static void lock_2_inodes(struct inode *inode1, struct inode *inode2)
693 mutex_lock_nested(&ubifs_inode(inode1)->ui_mutex, WB_MUTEX_1);
694 mutex_lock_nested(&ubifs_inode(inode2)->ui_mutex, WB_MUTEX_2);
698 * unlock_2_inodes - a wrapper for unlocking two UBIFS inodes.
699 * @inode1: first inode
700 * @inode2: second inode
702 static void unlock_2_inodes(struct inode *inode1, struct inode *inode2)
704 mutex_unlock(&ubifs_inode(inode2)->ui_mutex);
705 mutex_unlock(&ubifs_inode(inode1)->ui_mutex);
708 static int ubifs_link(struct dentry *old_dentry, struct inode *dir,
709 struct dentry *dentry)
711 struct ubifs_info *c = dir->i_sb->s_fs_info;
712 struct inode *inode = d_inode(old_dentry);
713 struct ubifs_inode *ui = ubifs_inode(inode);
714 struct ubifs_inode *dir_ui = ubifs_inode(dir);
715 int err, sz_change = CALC_DENT_SIZE(dentry->d_name.len);
716 struct ubifs_budget_req req = { .new_dent = 1, .dirtied_ino = 2,
717 .dirtied_ino_d = ALIGN(ui->data_len, 8) };
718 struct fscrypt_name nm;
721 * Budget request settings: new direntry, changing the target inode,
722 * changing the parent inode.
725 dbg_gen("dent '%pd' to ino %lu (nlink %d) in dir ino %lu",
726 dentry, inode->i_ino,
727 inode->i_nlink, dir->i_ino);
728 ubifs_assert(c, inode_is_locked(dir));
729 ubifs_assert(c, inode_is_locked(inode));
731 err = fscrypt_prepare_link(old_dentry, dir, dentry);
735 err = fscrypt_setup_filename(dir, &dentry->d_name, 0, &nm);
739 err = dbg_check_synced_i_size(c, inode);
743 err = ubifs_budget_space(c, &req);
747 lock_2_inodes(dir, inode);
749 /* Handle O_TMPFILE corner case, it is allowed to link a O_TMPFILE. */
750 if (inode->i_nlink == 0)
751 ubifs_delete_orphan(c, inode->i_ino);
755 inode->i_ctime = current_time(inode);
756 dir->i_size += sz_change;
757 dir_ui->ui_size = dir->i_size;
758 dir->i_mtime = dir->i_ctime = inode->i_ctime;
759 err = ubifs_jnl_update(c, dir, &nm, inode, 0, 0);
762 unlock_2_inodes(dir, inode);
764 ubifs_release_budget(c, &req);
765 d_instantiate(dentry, inode);
766 fscrypt_free_filename(&nm);
770 dir->i_size -= sz_change;
771 dir_ui->ui_size = dir->i_size;
773 if (inode->i_nlink == 0)
774 ubifs_add_orphan(c, inode->i_ino);
775 unlock_2_inodes(dir, inode);
776 ubifs_release_budget(c, &req);
779 fscrypt_free_filename(&nm);
783 static int ubifs_unlink(struct inode *dir, struct dentry *dentry)
785 struct ubifs_info *c = dir->i_sb->s_fs_info;
786 struct inode *inode = d_inode(dentry);
787 struct ubifs_inode *dir_ui = ubifs_inode(dir);
788 int err, sz_change, budgeted = 1;
789 struct ubifs_budget_req req = { .mod_dent = 1, .dirtied_ino = 2 };
790 unsigned int saved_nlink = inode->i_nlink;
791 struct fscrypt_name nm;
794 * Budget request settings: deletion direntry, deletion inode (+1 for
795 * @dirtied_ino), changing the parent directory inode. If budgeting
796 * fails, go ahead anyway because we have extra space reserved for
800 dbg_gen("dent '%pd' from ino %lu (nlink %d) in dir ino %lu",
801 dentry, inode->i_ino,
802 inode->i_nlink, dir->i_ino);
804 if (ubifs_crypt_is_encrypted(dir)) {
805 err = fscrypt_get_encryption_info(dir);
806 if (err && err != -ENOKEY)
810 err = fscrypt_setup_filename(dir, &dentry->d_name, 1, &nm);
814 sz_change = CALC_DENT_SIZE(fname_len(&nm));
816 ubifs_assert(c, inode_is_locked(dir));
817 ubifs_assert(c, inode_is_locked(inode));
818 err = dbg_check_synced_i_size(c, inode);
822 err = ubifs_budget_space(c, &req);
829 lock_2_inodes(dir, inode);
830 inode->i_ctime = current_time(dir);
832 dir->i_size -= sz_change;
833 dir_ui->ui_size = dir->i_size;
834 dir->i_mtime = dir->i_ctime = inode->i_ctime;
835 err = ubifs_jnl_update(c, dir, &nm, inode, 1, 0);
838 unlock_2_inodes(dir, inode);
841 ubifs_release_budget(c, &req);
843 /* We've deleted something - clean the "no space" flags */
844 c->bi.nospace = c->bi.nospace_rp = 0;
847 fscrypt_free_filename(&nm);
851 dir->i_size += sz_change;
852 dir_ui->ui_size = dir->i_size;
853 set_nlink(inode, saved_nlink);
854 unlock_2_inodes(dir, inode);
856 ubifs_release_budget(c, &req);
858 fscrypt_free_filename(&nm);
863 * check_dir_empty - check if a directory is empty or not.
864 * @dir: VFS inode object of the directory to check
866 * This function checks if directory @dir is empty. Returns zero if the
867 * directory is empty, %-ENOTEMPTY if it is not, and other negative error codes
868 * in case of of errors.
870 int ubifs_check_dir_empty(struct inode *dir)
872 struct ubifs_info *c = dir->i_sb->s_fs_info;
873 struct fscrypt_name nm = { 0 };
874 struct ubifs_dent_node *dent;
878 lowest_dent_key(c, &key, dir->i_ino);
879 dent = ubifs_tnc_next_ent(c, &key, &nm);
891 static int ubifs_rmdir(struct inode *dir, struct dentry *dentry)
893 struct ubifs_info *c = dir->i_sb->s_fs_info;
894 struct inode *inode = d_inode(dentry);
895 int err, sz_change, budgeted = 1;
896 struct ubifs_inode *dir_ui = ubifs_inode(dir);
897 struct ubifs_budget_req req = { .mod_dent = 1, .dirtied_ino = 2 };
898 struct fscrypt_name nm;
901 * Budget request settings: deletion direntry, deletion inode and
902 * changing the parent inode. If budgeting fails, go ahead anyway
903 * because we have extra space reserved for deletions.
906 dbg_gen("directory '%pd', ino %lu in dir ino %lu", dentry,
907 inode->i_ino, dir->i_ino);
908 ubifs_assert(c, inode_is_locked(dir));
909 ubifs_assert(c, inode_is_locked(inode));
910 err = ubifs_check_dir_empty(d_inode(dentry));
914 if (ubifs_crypt_is_encrypted(dir)) {
915 err = fscrypt_get_encryption_info(dir);
916 if (err && err != -ENOKEY)
920 err = fscrypt_setup_filename(dir, &dentry->d_name, 1, &nm);
924 sz_change = CALC_DENT_SIZE(fname_len(&nm));
926 err = ubifs_budget_space(c, &req);
933 lock_2_inodes(dir, inode);
934 inode->i_ctime = current_time(dir);
937 dir->i_size -= sz_change;
938 dir_ui->ui_size = dir->i_size;
939 dir->i_mtime = dir->i_ctime = inode->i_ctime;
940 err = ubifs_jnl_update(c, dir, &nm, inode, 1, 0);
943 unlock_2_inodes(dir, inode);
946 ubifs_release_budget(c, &req);
948 /* We've deleted something - clean the "no space" flags */
949 c->bi.nospace = c->bi.nospace_rp = 0;
952 fscrypt_free_filename(&nm);
956 dir->i_size += sz_change;
957 dir_ui->ui_size = dir->i_size;
960 unlock_2_inodes(dir, inode);
962 ubifs_release_budget(c, &req);
964 fscrypt_free_filename(&nm);
968 static int ubifs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
971 struct ubifs_inode *dir_ui = ubifs_inode(dir);
972 struct ubifs_info *c = dir->i_sb->s_fs_info;
974 struct ubifs_budget_req req = { .new_ino = 1, .new_dent = 1 };
975 struct fscrypt_name nm;
978 * Budget request settings: new inode, new direntry and changing parent
982 dbg_gen("dent '%pd', mode %#hx in dir ino %lu",
983 dentry, mode, dir->i_ino);
985 err = ubifs_budget_space(c, &req);
989 err = ubifs_prepare_create(dir, dentry, &nm);
993 sz_change = CALC_DENT_SIZE(fname_len(&nm));
995 inode = ubifs_new_inode(c, dir, S_IFDIR | mode);
997 err = PTR_ERR(inode);
1001 err = ubifs_init_security(dir, inode, &dentry->d_name);
1005 mutex_lock(&dir_ui->ui_mutex);
1006 insert_inode_hash(inode);
1009 dir->i_size += sz_change;
1010 dir_ui->ui_size = dir->i_size;
1011 dir->i_mtime = dir->i_ctime = inode->i_ctime;
1012 err = ubifs_jnl_update(c, dir, &nm, inode, 0, 0);
1014 ubifs_err(c, "cannot create directory, error %d", err);
1017 mutex_unlock(&dir_ui->ui_mutex);
1019 ubifs_release_budget(c, &req);
1020 d_instantiate(dentry, inode);
1021 fscrypt_free_filename(&nm);
1025 dir->i_size -= sz_change;
1026 dir_ui->ui_size = dir->i_size;
1028 mutex_unlock(&dir_ui->ui_mutex);
1030 make_bad_inode(inode);
1033 fscrypt_free_filename(&nm);
1035 ubifs_release_budget(c, &req);
1039 static int ubifs_mknod(struct inode *dir, struct dentry *dentry,
1040 umode_t mode, dev_t rdev)
1042 struct inode *inode;
1043 struct ubifs_inode *ui;
1044 struct ubifs_inode *dir_ui = ubifs_inode(dir);
1045 struct ubifs_info *c = dir->i_sb->s_fs_info;
1046 union ubifs_dev_desc *dev = NULL;
1048 int err, devlen = 0;
1049 struct ubifs_budget_req req = { .new_ino = 1, .new_dent = 1,
1051 struct fscrypt_name nm;
1054 * Budget request settings: new inode, new direntry and changing parent
1058 dbg_gen("dent '%pd' in dir ino %lu", dentry, dir->i_ino);
1060 if (S_ISBLK(mode) || S_ISCHR(mode)) {
1061 dev = kmalloc(sizeof(union ubifs_dev_desc), GFP_NOFS);
1064 devlen = ubifs_encode_dev(dev, rdev);
1067 req.new_ino_d = ALIGN(devlen, 8);
1068 err = ubifs_budget_space(c, &req);
1074 err = ubifs_prepare_create(dir, dentry, &nm);
1080 sz_change = CALC_DENT_SIZE(fname_len(&nm));
1082 inode = ubifs_new_inode(c, dir, mode);
1083 if (IS_ERR(inode)) {
1085 err = PTR_ERR(inode);
1089 init_special_inode(inode, inode->i_mode, rdev);
1090 inode->i_size = ubifs_inode(inode)->ui_size = devlen;
1091 ui = ubifs_inode(inode);
1093 ui->data_len = devlen;
1095 err = ubifs_init_security(dir, inode, &dentry->d_name);
1099 mutex_lock(&dir_ui->ui_mutex);
1100 dir->i_size += sz_change;
1101 dir_ui->ui_size = dir->i_size;
1102 dir->i_mtime = dir->i_ctime = inode->i_ctime;
1103 err = ubifs_jnl_update(c, dir, &nm, inode, 0, 0);
1106 mutex_unlock(&dir_ui->ui_mutex);
1108 ubifs_release_budget(c, &req);
1109 insert_inode_hash(inode);
1110 d_instantiate(dentry, inode);
1111 fscrypt_free_filename(&nm);
1115 dir->i_size -= sz_change;
1116 dir_ui->ui_size = dir->i_size;
1117 mutex_unlock(&dir_ui->ui_mutex);
1119 make_bad_inode(inode);
1122 fscrypt_free_filename(&nm);
1124 ubifs_release_budget(c, &req);
1128 static int ubifs_symlink(struct inode *dir, struct dentry *dentry,
1129 const char *symname)
1131 struct inode *inode;
1132 struct ubifs_inode *ui;
1133 struct ubifs_inode *dir_ui = ubifs_inode(dir);
1134 struct ubifs_info *c = dir->i_sb->s_fs_info;
1135 int err, sz_change, len = strlen(symname);
1136 struct fscrypt_str disk_link;
1137 struct ubifs_budget_req req = { .new_ino = 1, .new_dent = 1,
1138 .new_ino_d = ALIGN(len, 8),
1140 struct fscrypt_name nm;
1142 dbg_gen("dent '%pd', target '%s' in dir ino %lu", dentry,
1143 symname, dir->i_ino);
1145 err = fscrypt_prepare_symlink(dir, symname, len, UBIFS_MAX_INO_DATA,
1151 * Budget request settings: new inode, new direntry and changing parent
1154 err = ubifs_budget_space(c, &req);
1158 err = ubifs_prepare_create(dir, dentry, &nm);
1162 sz_change = CALC_DENT_SIZE(fname_len(&nm));
1164 inode = ubifs_new_inode(c, dir, S_IFLNK | S_IRWXUGO);
1165 if (IS_ERR(inode)) {
1166 err = PTR_ERR(inode);
1170 ui = ubifs_inode(inode);
1171 ui->data = kmalloc(disk_link.len, GFP_NOFS);
1177 if (IS_ENCRYPTED(inode)) {
1178 disk_link.name = ui->data; /* encrypt directly into ui->data */
1179 err = fscrypt_encrypt_symlink(inode, symname, len, &disk_link);
1183 memcpy(ui->data, disk_link.name, disk_link.len);
1184 inode->i_link = ui->data;
1188 * The terminating zero byte is not written to the flash media and it
1189 * is put just to make later in-memory string processing simpler. Thus,
1190 * data length is @disk_link.len - 1, not @disk_link.len.
1192 ui->data_len = disk_link.len - 1;
1193 inode->i_size = ubifs_inode(inode)->ui_size = disk_link.len - 1;
1195 err = ubifs_init_security(dir, inode, &dentry->d_name);
1199 mutex_lock(&dir_ui->ui_mutex);
1200 dir->i_size += sz_change;
1201 dir_ui->ui_size = dir->i_size;
1202 dir->i_mtime = dir->i_ctime = inode->i_ctime;
1203 err = ubifs_jnl_update(c, dir, &nm, inode, 0, 0);
1206 mutex_unlock(&dir_ui->ui_mutex);
1208 insert_inode_hash(inode);
1209 d_instantiate(dentry, inode);
1214 dir->i_size -= sz_change;
1215 dir_ui->ui_size = dir->i_size;
1216 mutex_unlock(&dir_ui->ui_mutex);
1218 make_bad_inode(inode);
1221 fscrypt_free_filename(&nm);
1223 ubifs_release_budget(c, &req);
1228 * lock_4_inodes - a wrapper for locking three UBIFS inodes.
1229 * @inode1: first inode
1230 * @inode2: second inode
1231 * @inode3: third inode
1232 * @inode4: fouth inode
1234 * This function is used for 'ubifs_rename()' and @inode1 may be the same as
1235 * @inode2 whereas @inode3 and @inode4 may be %NULL.
1237 * We do not implement any tricks to guarantee strict lock ordering, because
1238 * VFS has already done it for us on the @i_mutex. So this is just a simple
1241 static void lock_4_inodes(struct inode *inode1, struct inode *inode2,
1242 struct inode *inode3, struct inode *inode4)
1244 mutex_lock_nested(&ubifs_inode(inode1)->ui_mutex, WB_MUTEX_1);
1245 if (inode2 != inode1)
1246 mutex_lock_nested(&ubifs_inode(inode2)->ui_mutex, WB_MUTEX_2);
1248 mutex_lock_nested(&ubifs_inode(inode3)->ui_mutex, WB_MUTEX_3);
1250 mutex_lock_nested(&ubifs_inode(inode4)->ui_mutex, WB_MUTEX_4);
1254 * unlock_4_inodes - a wrapper for unlocking three UBIFS inodes for rename.
1255 * @inode1: first inode
1256 * @inode2: second inode
1257 * @inode3: third inode
1258 * @inode4: fouth inode
1260 static void unlock_4_inodes(struct inode *inode1, struct inode *inode2,
1261 struct inode *inode3, struct inode *inode4)
1264 mutex_unlock(&ubifs_inode(inode4)->ui_mutex);
1266 mutex_unlock(&ubifs_inode(inode3)->ui_mutex);
1267 if (inode1 != inode2)
1268 mutex_unlock(&ubifs_inode(inode2)->ui_mutex);
1269 mutex_unlock(&ubifs_inode(inode1)->ui_mutex);
1272 static int do_rename(struct inode *old_dir, struct dentry *old_dentry,
1273 struct inode *new_dir, struct dentry *new_dentry,
1276 struct ubifs_info *c = old_dir->i_sb->s_fs_info;
1277 struct inode *old_inode = d_inode(old_dentry);
1278 struct inode *new_inode = d_inode(new_dentry);
1279 struct inode *whiteout = NULL;
1280 struct ubifs_inode *old_inode_ui = ubifs_inode(old_inode);
1281 struct ubifs_inode *whiteout_ui = NULL;
1282 int err, release, sync = 0, move = (new_dir != old_dir);
1283 int is_dir = S_ISDIR(old_inode->i_mode);
1284 int unlink = !!new_inode, new_sz, old_sz;
1285 struct ubifs_budget_req req = { .new_dent = 1, .mod_dent = 1,
1287 struct ubifs_budget_req ino_req = { .dirtied_ino = 1,
1288 .dirtied_ino_d = ALIGN(old_inode_ui->data_len, 8) };
1289 struct timespec64 time;
1290 unsigned int uninitialized_var(saved_nlink);
1291 struct fscrypt_name old_nm, new_nm;
1294 * Budget request settings: deletion direntry, new direntry, removing
1295 * the old inode, and changing old and new parent directory inodes.
1297 * However, this operation also marks the target inode as dirty and
1298 * does not write it, so we allocate budget for the target inode
1302 dbg_gen("dent '%pd' ino %lu in dir ino %lu to dent '%pd' in dir ino %lu flags 0x%x",
1303 old_dentry, old_inode->i_ino, old_dir->i_ino,
1304 new_dentry, new_dir->i_ino, flags);
1307 ubifs_assert(c, inode_is_locked(new_inode));
1309 if (unlink && is_dir) {
1310 err = ubifs_check_dir_empty(new_inode);
1315 err = fscrypt_setup_filename(old_dir, &old_dentry->d_name, 0, &old_nm);
1319 err = fscrypt_setup_filename(new_dir, &new_dentry->d_name, 0, &new_nm);
1321 fscrypt_free_filename(&old_nm);
1325 new_sz = CALC_DENT_SIZE(fname_len(&new_nm));
1326 old_sz = CALC_DENT_SIZE(fname_len(&old_nm));
1328 err = ubifs_budget_space(c, &req);
1330 fscrypt_free_filename(&old_nm);
1331 fscrypt_free_filename(&new_nm);
1334 err = ubifs_budget_space(c, &ino_req);
1336 fscrypt_free_filename(&old_nm);
1337 fscrypt_free_filename(&new_nm);
1338 ubifs_release_budget(c, &req);
1342 if (flags & RENAME_WHITEOUT) {
1343 union ubifs_dev_desc *dev = NULL;
1345 dev = kmalloc(sizeof(union ubifs_dev_desc), GFP_NOFS);
1351 err = do_tmpfile(old_dir, old_dentry, S_IFCHR | WHITEOUT_MODE, &whiteout);
1357 spin_lock(&whiteout->i_lock);
1358 whiteout->i_state |= I_LINKABLE;
1359 spin_unlock(&whiteout->i_lock);
1361 whiteout_ui = ubifs_inode(whiteout);
1362 whiteout_ui->data = dev;
1363 whiteout_ui->data_len = ubifs_encode_dev(dev, MKDEV(0, 0));
1364 ubifs_assert(c, !whiteout_ui->dirty);
1367 lock_4_inodes(old_dir, new_dir, new_inode, whiteout);
1370 * Like most other Unix systems, set the @i_ctime for inodes on a
1373 time = current_time(old_dir);
1374 old_inode->i_ctime = time;
1376 /* We must adjust parent link count when renaming directories */
1380 * @old_dir loses a link because we are moving
1381 * @old_inode to a different directory.
1383 drop_nlink(old_dir);
1385 * @new_dir only gains a link if we are not also
1386 * overwriting an existing directory.
1392 * @old_inode is not moving to a different directory,
1393 * but @old_dir still loses a link if we are
1394 * overwriting an existing directory.
1397 drop_nlink(old_dir);
1401 old_dir->i_size -= old_sz;
1402 ubifs_inode(old_dir)->ui_size = old_dir->i_size;
1403 old_dir->i_mtime = old_dir->i_ctime = time;
1404 new_dir->i_mtime = new_dir->i_ctime = time;
1407 * And finally, if we unlinked a direntry which happened to have the
1408 * same name as the moved direntry, we have to decrement @i_nlink of
1409 * the unlinked inode and change its ctime.
1413 * Directories cannot have hard-links, so if this is a
1414 * directory, just clear @i_nlink.
1416 saved_nlink = new_inode->i_nlink;
1418 clear_nlink(new_inode);
1420 drop_nlink(new_inode);
1421 new_inode->i_ctime = time;
1423 new_dir->i_size += new_sz;
1424 ubifs_inode(new_dir)->ui_size = new_dir->i_size;
1428 * Do not ask 'ubifs_jnl_rename()' to flush write-buffer if @old_inode
1429 * is dirty, because this will be done later on at the end of
1432 if (IS_SYNC(old_inode)) {
1433 sync = IS_DIRSYNC(old_dir) || IS_DIRSYNC(new_dir);
1434 if (unlink && IS_SYNC(new_inode))
1439 struct ubifs_budget_req wht_req = { .dirtied_ino = 1,
1441 ALIGN(ubifs_inode(whiteout)->data_len, 8) };
1443 err = ubifs_budget_space(c, &wht_req);
1445 kfree(whiteout_ui->data);
1446 whiteout_ui->data_len = 0;
1451 inc_nlink(whiteout);
1452 mark_inode_dirty(whiteout);
1454 spin_lock(&whiteout->i_lock);
1455 whiteout->i_state &= ~I_LINKABLE;
1456 spin_unlock(&whiteout->i_lock);
1461 err = ubifs_jnl_rename(c, old_dir, old_inode, &old_nm, new_dir,
1462 new_inode, &new_nm, whiteout, sync);
1466 unlock_4_inodes(old_dir, new_dir, new_inode, whiteout);
1467 ubifs_release_budget(c, &req);
1469 mutex_lock(&old_inode_ui->ui_mutex);
1470 release = old_inode_ui->dirty;
1471 mark_inode_dirty_sync(old_inode);
1472 mutex_unlock(&old_inode_ui->ui_mutex);
1475 ubifs_release_budget(c, &ino_req);
1476 if (IS_SYNC(old_inode))
1477 err = old_inode->i_sb->s_op->write_inode(old_inode, NULL);
1479 fscrypt_free_filename(&old_nm);
1480 fscrypt_free_filename(&new_nm);
1485 set_nlink(new_inode, saved_nlink);
1487 new_dir->i_size -= new_sz;
1488 ubifs_inode(new_dir)->ui_size = new_dir->i_size;
1490 old_dir->i_size += old_sz;
1491 ubifs_inode(old_dir)->ui_size = old_dir->i_size;
1496 drop_nlink(new_dir);
1503 drop_nlink(whiteout);
1506 unlock_4_inodes(old_dir, new_dir, new_inode, whiteout);
1508 ubifs_release_budget(c, &ino_req);
1509 ubifs_release_budget(c, &req);
1510 fscrypt_free_filename(&old_nm);
1511 fscrypt_free_filename(&new_nm);
1515 static int ubifs_xrename(struct inode *old_dir, struct dentry *old_dentry,
1516 struct inode *new_dir, struct dentry *new_dentry)
1518 struct ubifs_info *c = old_dir->i_sb->s_fs_info;
1519 struct ubifs_budget_req req = { .new_dent = 1, .mod_dent = 1,
1521 int sync = IS_DIRSYNC(old_dir) || IS_DIRSYNC(new_dir);
1522 struct inode *fst_inode = d_inode(old_dentry);
1523 struct inode *snd_inode = d_inode(new_dentry);
1524 struct timespec64 time;
1526 struct fscrypt_name fst_nm, snd_nm;
1528 ubifs_assert(c, fst_inode && snd_inode);
1530 err = fscrypt_setup_filename(old_dir, &old_dentry->d_name, 0, &fst_nm);
1534 err = fscrypt_setup_filename(new_dir, &new_dentry->d_name, 0, &snd_nm);
1536 fscrypt_free_filename(&fst_nm);
1540 lock_4_inodes(old_dir, new_dir, NULL, NULL);
1542 time = current_time(old_dir);
1543 fst_inode->i_ctime = time;
1544 snd_inode->i_ctime = time;
1545 old_dir->i_mtime = old_dir->i_ctime = time;
1546 new_dir->i_mtime = new_dir->i_ctime = time;
1548 if (old_dir != new_dir) {
1549 if (S_ISDIR(fst_inode->i_mode) && !S_ISDIR(snd_inode->i_mode)) {
1551 drop_nlink(old_dir);
1553 else if (!S_ISDIR(fst_inode->i_mode) && S_ISDIR(snd_inode->i_mode)) {
1554 drop_nlink(new_dir);
1559 err = ubifs_jnl_xrename(c, old_dir, fst_inode, &fst_nm, new_dir,
1560 snd_inode, &snd_nm, sync);
1562 unlock_4_inodes(old_dir, new_dir, NULL, NULL);
1563 ubifs_release_budget(c, &req);
1565 fscrypt_free_filename(&fst_nm);
1566 fscrypt_free_filename(&snd_nm);
1570 static int ubifs_rename(struct inode *old_dir, struct dentry *old_dentry,
1571 struct inode *new_dir, struct dentry *new_dentry,
1575 struct ubifs_info *c = old_dir->i_sb->s_fs_info;
1577 if (flags & ~(RENAME_NOREPLACE | RENAME_WHITEOUT | RENAME_EXCHANGE))
1580 ubifs_assert(c, inode_is_locked(old_dir));
1581 ubifs_assert(c, inode_is_locked(new_dir));
1583 err = fscrypt_prepare_rename(old_dir, old_dentry, new_dir, new_dentry,
1588 if (flags & RENAME_EXCHANGE)
1589 return ubifs_xrename(old_dir, old_dentry, new_dir, new_dentry);
1591 return do_rename(old_dir, old_dentry, new_dir, new_dentry, flags);
1594 int ubifs_getattr(const struct path *path, struct kstat *stat,
1595 u32 request_mask, unsigned int flags)
1598 struct inode *inode = d_inode(path->dentry);
1599 struct ubifs_inode *ui = ubifs_inode(inode);
1601 mutex_lock(&ui->ui_mutex);
1603 if (ui->flags & UBIFS_APPEND_FL)
1604 stat->attributes |= STATX_ATTR_APPEND;
1605 if (ui->flags & UBIFS_COMPR_FL)
1606 stat->attributes |= STATX_ATTR_COMPRESSED;
1607 if (ui->flags & UBIFS_CRYPT_FL)
1608 stat->attributes |= STATX_ATTR_ENCRYPTED;
1609 if (ui->flags & UBIFS_IMMUTABLE_FL)
1610 stat->attributes |= STATX_ATTR_IMMUTABLE;
1612 stat->attributes_mask |= (STATX_ATTR_APPEND |
1613 STATX_ATTR_COMPRESSED |
1614 STATX_ATTR_ENCRYPTED |
1615 STATX_ATTR_IMMUTABLE);
1617 generic_fillattr(inode, stat);
1618 stat->blksize = UBIFS_BLOCK_SIZE;
1619 stat->size = ui->ui_size;
1622 * Unfortunately, the 'stat()' system call was designed for block
1623 * device based file systems, and it is not appropriate for UBIFS,
1624 * because UBIFS does not have notion of "block". For example, it is
1625 * difficult to tell how many block a directory takes - it actually
1626 * takes less than 300 bytes, but we have to round it to block size,
1627 * which introduces large mistake. This makes utilities like 'du' to
1628 * report completely senseless numbers. This is the reason why UBIFS
1629 * goes the same way as JFFS2 - it reports zero blocks for everything
1630 * but regular files, which makes more sense than reporting completely
1633 if (S_ISREG(inode->i_mode)) {
1634 size = ui->xattr_size;
1636 size = ALIGN(size, UBIFS_BLOCK_SIZE);
1638 * Note, user-space expects 512-byte blocks count irrespectively
1639 * of what was reported in @stat->size.
1641 stat->blocks = size >> 9;
1644 mutex_unlock(&ui->ui_mutex);
1648 static int ubifs_dir_open(struct inode *dir, struct file *file)
1650 if (ubifs_crypt_is_encrypted(dir))
1651 return fscrypt_get_encryption_info(dir) ? -EACCES : 0;
1656 const struct inode_operations ubifs_dir_inode_operations = {
1657 .lookup = ubifs_lookup,
1658 .create = ubifs_create,
1660 .symlink = ubifs_symlink,
1661 .unlink = ubifs_unlink,
1662 .mkdir = ubifs_mkdir,
1663 .rmdir = ubifs_rmdir,
1664 .mknod = ubifs_mknod,
1665 .rename = ubifs_rename,
1666 .setattr = ubifs_setattr,
1667 .getattr = ubifs_getattr,
1668 #ifdef CONFIG_UBIFS_FS_XATTR
1669 .listxattr = ubifs_listxattr,
1671 #ifdef CONFIG_UBIFS_ATIME_SUPPORT
1672 .update_time = ubifs_update_time,
1674 .tmpfile = ubifs_tmpfile,
1677 const struct file_operations ubifs_dir_operations = {
1678 .llseek = generic_file_llseek,
1679 .release = ubifs_dir_release,
1680 .read = generic_read_dir,
1681 .iterate_shared = ubifs_readdir,
1682 .fsync = ubifs_fsync,
1683 .unlocked_ioctl = ubifs_ioctl,
1684 .open = ubifs_dir_open,
1685 #ifdef CONFIG_COMPAT
1686 .compat_ioctl = ubifs_compat_ioctl,