1 // SPDX-License-Identifier: GPL-2.0-only
2 /* * This file is part of UBIFS.
4 * Copyright (C) 2006-2008 Nokia Corporation.
5 * Copyright (C) 2006, 2007 University of Szeged, Hungary
7 * Authors: Artem Bityutskiy (Битюцкий Артём)
13 * This file implements directory operations.
15 * All FS operations in this file allocate budget before writing anything to the
16 * media. If they fail to allocate it, the error is returned. The only
17 * exceptions are 'ubifs_unlink()' and 'ubifs_rmdir()' which keep working even
18 * if they unable to allocate the budget, because deletion %-ENOSPC failure is
19 * not what users are usually ready to get. UBIFS budgeting subsystem has some
20 * space reserved for these purposes.
22 * All operations in this file write all inodes which they change straight
23 * away, instead of marking them dirty. For example, 'ubifs_link()' changes
24 * @i_size of the parent inode and writes the parent inode together with the
25 * target inode. This was done to simplify file-system recovery which would
26 * otherwise be very difficult to do. The only exception is rename which marks
27 * the re-named inode dirty (because its @i_ctime is updated) but does not
28 * write it, but just marks it as dirty.
34 * inherit_flags - inherit flags of the parent inode.
36 * @mode: new inode mode flags
38 * This is a helper function for 'ubifs_new_inode()' which inherits flag of the
39 * parent directory inode @dir. UBIFS inodes inherit the following flags:
40 * o %UBIFS_COMPR_FL, which is useful to switch compression on/of on
41 * sub-directory basis;
42 * o %UBIFS_SYNC_FL - useful for the same reasons;
43 * o %UBIFS_DIRSYNC_FL - similar, but relevant only to directories.
45 * This function returns the inherited flags.
47 static int inherit_flags(const struct inode *dir, umode_t mode)
50 const struct ubifs_inode *ui = ubifs_inode(dir);
52 if (!S_ISDIR(dir->i_mode))
54 * The parent is not a directory, which means that an extended
55 * attribute inode is being created. No flags.
59 flags = ui->flags & (UBIFS_COMPR_FL | UBIFS_SYNC_FL | UBIFS_DIRSYNC_FL);
61 /* The "DIRSYNC" flag only applies to directories */
62 flags &= ~UBIFS_DIRSYNC_FL;
67 * ubifs_new_inode - allocate new UBIFS inode object.
68 * @c: UBIFS file-system description object
69 * @dir: parent directory inode
70 * @mode: inode mode flags
72 * This function finds an unused inode number, allocates new inode and
73 * initializes it. Returns new inode in case of success and an error code in
76 struct inode *ubifs_new_inode(struct ubifs_info *c, struct inode *dir,
81 struct ubifs_inode *ui;
82 bool encrypted = false;
84 inode = new_inode(c->vfs_sb);
85 ui = ubifs_inode(inode);
87 return ERR_PTR(-ENOMEM);
90 * Set 'S_NOCMTIME' to prevent VFS form updating [mc]time of inodes and
91 * marking them dirty in file write path (see 'file_update_time()').
92 * UBIFS has to fully control "clean <-> dirty" transitions of inodes
93 * to make budgeting work.
95 inode->i_flags |= S_NOCMTIME;
97 inode_init_owner(inode, dir, mode);
98 inode->i_mtime = inode->i_atime = inode->i_ctime =
100 inode->i_mapping->nrpages = 0;
102 err = fscrypt_prepare_new_inode(dir, inode, &encrypted);
104 ubifs_err(c, "fscrypt_prepare_new_inode failed: %i", err);
108 switch (mode & S_IFMT) {
110 inode->i_mapping->a_ops = &ubifs_file_address_operations;
111 inode->i_op = &ubifs_file_inode_operations;
112 inode->i_fop = &ubifs_file_operations;
115 inode->i_op = &ubifs_dir_inode_operations;
116 inode->i_fop = &ubifs_dir_operations;
117 inode->i_size = ui->ui_size = UBIFS_INO_NODE_SZ;
120 inode->i_op = &ubifs_symlink_inode_operations;
126 inode->i_op = &ubifs_file_inode_operations;
132 ui->flags = inherit_flags(dir, mode);
133 ubifs_set_inode_flags(inode);
135 ui->compr_type = c->default_compr;
137 ui->compr_type = UBIFS_COMPR_NONE;
138 ui->synced_i_size = 0;
140 spin_lock(&c->cnt_lock);
141 /* Inode number overflow is currently not supported */
142 if (c->highest_inum >= INUM_WARN_WATERMARK) {
143 if (c->highest_inum >= INUM_WATERMARK) {
144 spin_unlock(&c->cnt_lock);
145 ubifs_err(c, "out of inode numbers");
149 ubifs_warn(c, "running out of inode numbers (current %lu, max %u)",
150 (unsigned long)c->highest_inum, INUM_WATERMARK);
153 inode->i_ino = ++c->highest_inum;
155 * The creation sequence number remains with this inode for its
156 * lifetime. All nodes for this inode have a greater sequence number,
157 * and so it is possible to distinguish obsolete nodes belonging to a
158 * previous incarnation of the same inode number - for example, for the
159 * purpose of rebuilding the index.
161 ui->creat_sqnum = ++c->max_sqnum;
162 spin_unlock(&c->cnt_lock);
165 err = fscrypt_set_context(inode, NULL);
167 ubifs_err(c, "fscrypt_set_context failed: %i", err);
175 make_bad_inode(inode);
180 static int dbg_check_name(const struct ubifs_info *c,
181 const struct ubifs_dent_node *dent,
182 const struct fscrypt_name *nm)
184 if (!dbg_is_chk_gen(c))
186 if (le16_to_cpu(dent->nlen) != fname_len(nm))
188 if (memcmp(dent->name, fname_name(nm), fname_len(nm)))
193 static struct dentry *ubifs_lookup(struct inode *dir, struct dentry *dentry,
198 struct inode *inode = NULL;
199 struct ubifs_dent_node *dent = NULL;
200 struct ubifs_info *c = dir->i_sb->s_fs_info;
201 struct fscrypt_name nm;
203 dbg_gen("'%pd' in dir ino %lu", dentry, dir->i_ino);
205 err = fscrypt_prepare_lookup(dir, dentry, &nm);
206 generic_set_encrypted_ci_d_ops(dentry);
208 return d_splice_alias(NULL, dentry);
212 if (fname_len(&nm) > UBIFS_MAX_NLEN) {
213 inode = ERR_PTR(-ENAMETOOLONG);
217 dent = kmalloc(UBIFS_MAX_DENT_NODE_SZ, GFP_NOFS);
219 inode = ERR_PTR(-ENOMEM);
223 if (fname_name(&nm) == NULL) {
224 if (nm.hash & ~UBIFS_S_KEY_HASH_MASK)
225 goto done; /* ENOENT */
226 dent_key_init_hash(c, &key, dir->i_ino, nm.hash);
227 err = ubifs_tnc_lookup_dh(c, &key, dent, nm.minor_hash);
229 dent_key_init(c, &key, dir->i_ino, &nm);
230 err = ubifs_tnc_lookup_nm(c, &key, dent, &nm);
235 dbg_gen("not found");
237 inode = ERR_PTR(err);
241 if (dbg_check_name(c, dent, &nm)) {
242 inode = ERR_PTR(-EINVAL);
246 inode = ubifs_iget(dir->i_sb, le64_to_cpu(dent->inum));
249 * This should not happen. Probably the file-system needs
252 err = PTR_ERR(inode);
253 ubifs_err(c, "dead directory entry '%pd', error %d",
255 ubifs_ro_mode(c, err);
259 if (IS_ENCRYPTED(dir) &&
260 (S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode)) &&
261 !fscrypt_has_permitted_context(dir, inode)) {
262 ubifs_warn(c, "Inconsistent encryption contexts: %lu/%lu",
263 dir->i_ino, inode->i_ino);
265 inode = ERR_PTR(-EPERM);
270 fscrypt_free_filename(&nm);
271 return d_splice_alias(inode, dentry);
274 static int ubifs_prepare_create(struct inode *dir, struct dentry *dentry,
275 struct fscrypt_name *nm)
277 if (fscrypt_is_nokey_name(dentry))
280 return fscrypt_setup_filename(dir, &dentry->d_name, 0, nm);
283 static int ubifs_create(struct inode *dir, struct dentry *dentry, umode_t mode,
287 struct ubifs_info *c = dir->i_sb->s_fs_info;
288 struct ubifs_budget_req req = { .new_ino = 1, .new_dent = 1,
290 struct ubifs_inode *dir_ui = ubifs_inode(dir);
291 struct fscrypt_name nm;
295 * Budget request settings: new inode, new direntry, changing the
296 * parent directory inode.
299 dbg_gen("dent '%pd', mode %#hx in dir ino %lu",
300 dentry, mode, dir->i_ino);
302 err = ubifs_budget_space(c, &req);
306 err = ubifs_prepare_create(dir, dentry, &nm);
310 sz_change = CALC_DENT_SIZE(fname_len(&nm));
312 inode = ubifs_new_inode(c, dir, mode);
314 err = PTR_ERR(inode);
318 err = ubifs_init_security(dir, inode, &dentry->d_name);
322 mutex_lock(&dir_ui->ui_mutex);
323 dir->i_size += sz_change;
324 dir_ui->ui_size = dir->i_size;
325 dir->i_mtime = dir->i_ctime = inode->i_ctime;
326 err = ubifs_jnl_update(c, dir, &nm, inode, 0, 0);
329 mutex_unlock(&dir_ui->ui_mutex);
331 ubifs_release_budget(c, &req);
332 fscrypt_free_filename(&nm);
333 insert_inode_hash(inode);
334 d_instantiate(dentry, inode);
338 dir->i_size -= sz_change;
339 dir_ui->ui_size = dir->i_size;
340 mutex_unlock(&dir_ui->ui_mutex);
342 make_bad_inode(inode);
345 fscrypt_free_filename(&nm);
347 ubifs_release_budget(c, &req);
348 ubifs_err(c, "cannot create regular file, error %d", err);
352 static int do_tmpfile(struct inode *dir, struct dentry *dentry,
353 umode_t mode, struct inode **whiteout)
356 struct ubifs_info *c = dir->i_sb->s_fs_info;
357 struct ubifs_budget_req req = { .new_ino = 1, .new_dent = 1};
358 struct ubifs_budget_req ino_req = { .dirtied_ino = 1 };
359 struct ubifs_inode *ui, *dir_ui = ubifs_inode(dir);
360 int err, instantiated = 0;
361 struct fscrypt_name nm;
364 * Budget request settings: new dirty inode, new direntry,
365 * budget for dirtied inode will be released via writeback.
368 dbg_gen("dent '%pd', mode %#hx in dir ino %lu",
369 dentry, mode, dir->i_ino);
371 err = fscrypt_setup_filename(dir, &dentry->d_name, 0, &nm);
375 err = ubifs_budget_space(c, &req);
377 fscrypt_free_filename(&nm);
381 err = ubifs_budget_space(c, &ino_req);
383 ubifs_release_budget(c, &req);
384 fscrypt_free_filename(&nm);
388 inode = ubifs_new_inode(c, dir, mode);
390 err = PTR_ERR(inode);
393 ui = ubifs_inode(inode);
396 init_special_inode(inode, inode->i_mode, WHITEOUT_DEV);
397 ubifs_assert(c, inode->i_op == &ubifs_file_inode_operations);
400 err = ubifs_init_security(dir, inode, &dentry->d_name);
404 mutex_lock(&ui->ui_mutex);
405 insert_inode_hash(inode);
408 mark_inode_dirty(inode);
412 d_tmpfile(dentry, inode);
414 ubifs_assert(c, ui->dirty);
417 mutex_unlock(&ui->ui_mutex);
419 mutex_lock(&dir_ui->ui_mutex);
420 err = ubifs_jnl_update(c, dir, &nm, inode, 1, 0);
423 mutex_unlock(&dir_ui->ui_mutex);
425 ubifs_release_budget(c, &req);
430 mutex_unlock(&dir_ui->ui_mutex);
432 make_bad_inode(inode);
436 ubifs_release_budget(c, &req);
438 ubifs_release_budget(c, &ino_req);
439 fscrypt_free_filename(&nm);
440 ubifs_err(c, "cannot create temporary file, error %d", err);
444 static int ubifs_tmpfile(struct inode *dir, struct dentry *dentry,
447 return do_tmpfile(dir, dentry, mode, NULL);
451 * vfs_dent_type - get VFS directory entry type.
452 * @type: UBIFS directory entry type
454 * This function converts UBIFS directory entry type into VFS directory entry
457 static unsigned int vfs_dent_type(uint8_t type)
460 case UBIFS_ITYPE_REG:
462 case UBIFS_ITYPE_DIR:
464 case UBIFS_ITYPE_LNK:
466 case UBIFS_ITYPE_BLK:
468 case UBIFS_ITYPE_CHR:
470 case UBIFS_ITYPE_FIFO:
472 case UBIFS_ITYPE_SOCK:
481 * The classical Unix view for directory is that it is a linear array of
482 * (name, inode number) entries. Linux/VFS assumes this model as well.
483 * Particularly, 'readdir()' call wants us to return a directory entry offset
484 * which later may be used to continue 'readdir()'ing the directory or to
485 * 'seek()' to that specific direntry. Obviously UBIFS does not really fit this
486 * model because directory entries are identified by keys, which may collide.
488 * UBIFS uses directory entry hash value for directory offsets, so
489 * 'seekdir()'/'telldir()' may not always work because of possible key
490 * collisions. But UBIFS guarantees that consecutive 'readdir()' calls work
491 * properly by means of saving full directory entry name in the private field
492 * of the file description object.
494 * This means that UBIFS cannot support NFS which requires full
495 * 'seekdir()'/'telldir()' support.
497 static int ubifs_readdir(struct file *file, struct dir_context *ctx)
499 int fstr_real_len = 0, err = 0;
500 struct fscrypt_name nm;
501 struct fscrypt_str fstr = {0};
503 struct ubifs_dent_node *dent;
504 struct inode *dir = file_inode(file);
505 struct ubifs_info *c = dir->i_sb->s_fs_info;
506 bool encrypted = IS_ENCRYPTED(dir);
508 dbg_gen("dir ino %lu, f_pos %#llx", dir->i_ino, ctx->pos);
510 if (ctx->pos > UBIFS_S_KEY_HASH_MASK || ctx->pos == 2)
512 * The directory was seek'ed to a senseless position or there
513 * are no more entries.
518 err = fscrypt_prepare_readdir(dir);
522 err = fscrypt_fname_alloc_buffer(UBIFS_MAX_NLEN, &fstr);
526 fstr_real_len = fstr.len;
529 if (file->f_version == 0) {
531 * The file was seek'ed, which means that @file->private_data
532 * is now invalid. This may also be just the first
533 * 'ubifs_readdir()' invocation, in which case
534 * @file->private_data is NULL, and the below code is
537 kfree(file->private_data);
538 file->private_data = NULL;
542 * 'generic_file_llseek()' unconditionally sets @file->f_version to
543 * zero, and we use this for detecting whether the file was seek'ed.
547 /* File positions 0 and 1 correspond to "." and ".." */
549 ubifs_assert(c, !file->private_data);
550 if (!dir_emit_dots(file, ctx)) {
552 fscrypt_fname_free_buffer(&fstr);
556 /* Find the first entry in TNC and save it */
557 lowest_dent_key(c, &key, dir->i_ino);
559 dent = ubifs_tnc_next_ent(c, &key, &nm);
565 ctx->pos = key_hash_flash(c, &dent->key);
566 file->private_data = dent;
569 dent = file->private_data;
572 * The directory was seek'ed to and is now readdir'ed.
573 * Find the entry corresponding to @ctx->pos or the closest one.
575 dent_key_init_hash(c, &key, dir->i_ino, ctx->pos);
577 dent = ubifs_tnc_next_ent(c, &key, &nm);
582 ctx->pos = key_hash_flash(c, &dent->key);
583 file->private_data = dent;
587 dbg_gen("ino %llu, new f_pos %#x",
588 (unsigned long long)le64_to_cpu(dent->inum),
589 key_hash_flash(c, &dent->key));
590 ubifs_assert(c, le64_to_cpu(dent->ch.sqnum) >
591 ubifs_inode(dir)->creat_sqnum);
593 fname_len(&nm) = le16_to_cpu(dent->nlen);
594 fname_name(&nm) = dent->name;
597 fstr.len = fstr_real_len;
599 err = fscrypt_fname_disk_to_usr(dir, key_hash_flash(c,
601 le32_to_cpu(dent->cookie),
602 &nm.disk_name, &fstr);
606 fstr.len = fname_len(&nm);
607 fstr.name = fname_name(&nm);
610 if (!dir_emit(ctx, fstr.name, fstr.len,
611 le64_to_cpu(dent->inum),
612 vfs_dent_type(dent->type))) {
614 fscrypt_fname_free_buffer(&fstr);
618 /* Switch to the next entry */
619 key_read(c, &dent->key, &key);
620 dent = ubifs_tnc_next_ent(c, &key, &nm);
626 kfree(file->private_data);
627 ctx->pos = key_hash_flash(c, &dent->key);
628 file->private_data = dent;
633 kfree(file->private_data);
634 file->private_data = NULL;
637 fscrypt_fname_free_buffer(&fstr);
640 ubifs_err(c, "cannot find next direntry, error %d", err);
643 * -ENOENT is a non-fatal error in this context, the TNC uses
644 * it to indicate that the cursor moved past the current directory
645 * and readdir() has to stop.
650 /* 2 is a special value indicating that there are no more direntries */
655 /* Free saved readdir() state when the directory is closed */
656 static int ubifs_dir_release(struct inode *dir, struct file *file)
658 kfree(file->private_data);
659 file->private_data = NULL;
664 * lock_2_inodes - a wrapper for locking two UBIFS inodes.
665 * @inode1: first inode
666 * @inode2: second inode
668 * We do not implement any tricks to guarantee strict lock ordering, because
669 * VFS has already done it for us on the @i_mutex. So this is just a simple
672 static void lock_2_inodes(struct inode *inode1, struct inode *inode2)
674 mutex_lock_nested(&ubifs_inode(inode1)->ui_mutex, WB_MUTEX_1);
675 mutex_lock_nested(&ubifs_inode(inode2)->ui_mutex, WB_MUTEX_2);
679 * unlock_2_inodes - a wrapper for unlocking two UBIFS inodes.
680 * @inode1: first inode
681 * @inode2: second inode
683 static void unlock_2_inodes(struct inode *inode1, struct inode *inode2)
685 mutex_unlock(&ubifs_inode(inode2)->ui_mutex);
686 mutex_unlock(&ubifs_inode(inode1)->ui_mutex);
689 static int ubifs_link(struct dentry *old_dentry, struct inode *dir,
690 struct dentry *dentry)
692 struct ubifs_info *c = dir->i_sb->s_fs_info;
693 struct inode *inode = d_inode(old_dentry);
694 struct ubifs_inode *ui = ubifs_inode(inode);
695 struct ubifs_inode *dir_ui = ubifs_inode(dir);
696 int err, sz_change = CALC_DENT_SIZE(dentry->d_name.len);
697 struct ubifs_budget_req req = { .new_dent = 1, .dirtied_ino = 2,
698 .dirtied_ino_d = ALIGN(ui->data_len, 8) };
699 struct fscrypt_name nm;
702 * Budget request settings: new direntry, changing the target inode,
703 * changing the parent inode.
706 dbg_gen("dent '%pd' to ino %lu (nlink %d) in dir ino %lu",
707 dentry, inode->i_ino,
708 inode->i_nlink, dir->i_ino);
709 ubifs_assert(c, inode_is_locked(dir));
710 ubifs_assert(c, inode_is_locked(inode));
712 err = fscrypt_prepare_link(old_dentry, dir, dentry);
716 err = fscrypt_setup_filename(dir, &dentry->d_name, 0, &nm);
720 err = dbg_check_synced_i_size(c, inode);
724 err = ubifs_budget_space(c, &req);
728 lock_2_inodes(dir, inode);
730 /* Handle O_TMPFILE corner case, it is allowed to link a O_TMPFILE. */
731 if (inode->i_nlink == 0)
732 ubifs_delete_orphan(c, inode->i_ino);
736 inode->i_ctime = current_time(inode);
737 dir->i_size += sz_change;
738 dir_ui->ui_size = dir->i_size;
739 dir->i_mtime = dir->i_ctime = inode->i_ctime;
740 err = ubifs_jnl_update(c, dir, &nm, inode, 0, 0);
743 unlock_2_inodes(dir, inode);
745 ubifs_release_budget(c, &req);
746 d_instantiate(dentry, inode);
747 fscrypt_free_filename(&nm);
751 dir->i_size -= sz_change;
752 dir_ui->ui_size = dir->i_size;
754 if (inode->i_nlink == 0)
755 ubifs_add_orphan(c, inode->i_ino);
756 unlock_2_inodes(dir, inode);
757 ubifs_release_budget(c, &req);
760 fscrypt_free_filename(&nm);
764 static int ubifs_unlink(struct inode *dir, struct dentry *dentry)
766 struct ubifs_info *c = dir->i_sb->s_fs_info;
767 struct inode *inode = d_inode(dentry);
768 struct ubifs_inode *dir_ui = ubifs_inode(dir);
769 int err, sz_change, budgeted = 1;
770 struct ubifs_budget_req req = { .mod_dent = 1, .dirtied_ino = 2 };
771 unsigned int saved_nlink = inode->i_nlink;
772 struct fscrypt_name nm;
775 * Budget request settings: deletion direntry, deletion inode (+1 for
776 * @dirtied_ino), changing the parent directory inode. If budgeting
777 * fails, go ahead anyway because we have extra space reserved for
781 dbg_gen("dent '%pd' from ino %lu (nlink %d) in dir ino %lu",
782 dentry, inode->i_ino,
783 inode->i_nlink, dir->i_ino);
785 err = fscrypt_setup_filename(dir, &dentry->d_name, 1, &nm);
789 err = ubifs_purge_xattrs(inode);
793 sz_change = CALC_DENT_SIZE(fname_len(&nm));
795 ubifs_assert(c, inode_is_locked(dir));
796 ubifs_assert(c, inode_is_locked(inode));
797 err = dbg_check_synced_i_size(c, inode);
801 err = ubifs_budget_space(c, &req);
808 lock_2_inodes(dir, inode);
809 inode->i_ctime = current_time(dir);
811 dir->i_size -= sz_change;
812 dir_ui->ui_size = dir->i_size;
813 dir->i_mtime = dir->i_ctime = inode->i_ctime;
814 err = ubifs_jnl_update(c, dir, &nm, inode, 1, 0);
817 unlock_2_inodes(dir, inode);
820 ubifs_release_budget(c, &req);
822 /* We've deleted something - clean the "no space" flags */
823 c->bi.nospace = c->bi.nospace_rp = 0;
826 fscrypt_free_filename(&nm);
830 dir->i_size += sz_change;
831 dir_ui->ui_size = dir->i_size;
832 set_nlink(inode, saved_nlink);
833 unlock_2_inodes(dir, inode);
835 ubifs_release_budget(c, &req);
837 fscrypt_free_filename(&nm);
842 * check_dir_empty - check if a directory is empty or not.
843 * @dir: VFS inode object of the directory to check
845 * This function checks if directory @dir is empty. Returns zero if the
846 * directory is empty, %-ENOTEMPTY if it is not, and other negative error codes
849 int ubifs_check_dir_empty(struct inode *dir)
851 struct ubifs_info *c = dir->i_sb->s_fs_info;
852 struct fscrypt_name nm = { 0 };
853 struct ubifs_dent_node *dent;
857 lowest_dent_key(c, &key, dir->i_ino);
858 dent = ubifs_tnc_next_ent(c, &key, &nm);
870 static int ubifs_rmdir(struct inode *dir, struct dentry *dentry)
872 struct ubifs_info *c = dir->i_sb->s_fs_info;
873 struct inode *inode = d_inode(dentry);
874 int err, sz_change, budgeted = 1;
875 struct ubifs_inode *dir_ui = ubifs_inode(dir);
876 struct ubifs_budget_req req = { .mod_dent = 1, .dirtied_ino = 2 };
877 struct fscrypt_name nm;
880 * Budget request settings: deletion direntry, deletion inode and
881 * changing the parent inode. If budgeting fails, go ahead anyway
882 * because we have extra space reserved for deletions.
885 dbg_gen("directory '%pd', ino %lu in dir ino %lu", dentry,
886 inode->i_ino, dir->i_ino);
887 ubifs_assert(c, inode_is_locked(dir));
888 ubifs_assert(c, inode_is_locked(inode));
889 err = ubifs_check_dir_empty(d_inode(dentry));
893 err = fscrypt_setup_filename(dir, &dentry->d_name, 1, &nm);
897 err = ubifs_purge_xattrs(inode);
901 sz_change = CALC_DENT_SIZE(fname_len(&nm));
903 err = ubifs_budget_space(c, &req);
910 lock_2_inodes(dir, inode);
911 inode->i_ctime = current_time(dir);
914 dir->i_size -= sz_change;
915 dir_ui->ui_size = dir->i_size;
916 dir->i_mtime = dir->i_ctime = inode->i_ctime;
917 err = ubifs_jnl_update(c, dir, &nm, inode, 1, 0);
920 unlock_2_inodes(dir, inode);
923 ubifs_release_budget(c, &req);
925 /* We've deleted something - clean the "no space" flags */
926 c->bi.nospace = c->bi.nospace_rp = 0;
929 fscrypt_free_filename(&nm);
933 dir->i_size += sz_change;
934 dir_ui->ui_size = dir->i_size;
937 unlock_2_inodes(dir, inode);
939 ubifs_release_budget(c, &req);
941 fscrypt_free_filename(&nm);
945 static int ubifs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
948 struct ubifs_inode *dir_ui = ubifs_inode(dir);
949 struct ubifs_info *c = dir->i_sb->s_fs_info;
951 struct ubifs_budget_req req = { .new_ino = 1, .new_dent = 1 };
952 struct fscrypt_name nm;
955 * Budget request settings: new inode, new direntry and changing parent
959 dbg_gen("dent '%pd', mode %#hx in dir ino %lu",
960 dentry, mode, dir->i_ino);
962 err = ubifs_budget_space(c, &req);
966 err = ubifs_prepare_create(dir, dentry, &nm);
970 sz_change = CALC_DENT_SIZE(fname_len(&nm));
972 inode = ubifs_new_inode(c, dir, S_IFDIR | mode);
974 err = PTR_ERR(inode);
978 err = ubifs_init_security(dir, inode, &dentry->d_name);
982 mutex_lock(&dir_ui->ui_mutex);
983 insert_inode_hash(inode);
986 dir->i_size += sz_change;
987 dir_ui->ui_size = dir->i_size;
988 dir->i_mtime = dir->i_ctime = inode->i_ctime;
989 err = ubifs_jnl_update(c, dir, &nm, inode, 0, 0);
991 ubifs_err(c, "cannot create directory, error %d", err);
994 mutex_unlock(&dir_ui->ui_mutex);
996 ubifs_release_budget(c, &req);
997 d_instantiate(dentry, inode);
998 fscrypt_free_filename(&nm);
1002 dir->i_size -= sz_change;
1003 dir_ui->ui_size = dir->i_size;
1005 mutex_unlock(&dir_ui->ui_mutex);
1007 make_bad_inode(inode);
1010 fscrypt_free_filename(&nm);
1012 ubifs_release_budget(c, &req);
1016 static int ubifs_mknod(struct inode *dir, struct dentry *dentry,
1017 umode_t mode, dev_t rdev)
1019 struct inode *inode;
1020 struct ubifs_inode *ui;
1021 struct ubifs_inode *dir_ui = ubifs_inode(dir);
1022 struct ubifs_info *c = dir->i_sb->s_fs_info;
1023 union ubifs_dev_desc *dev = NULL;
1025 int err, devlen = 0;
1026 struct ubifs_budget_req req = { .new_ino = 1, .new_dent = 1,
1028 struct fscrypt_name nm;
1031 * Budget request settings: new inode, new direntry and changing parent
1035 dbg_gen("dent '%pd' in dir ino %lu", dentry, dir->i_ino);
1037 if (S_ISBLK(mode) || S_ISCHR(mode)) {
1038 dev = kmalloc(sizeof(union ubifs_dev_desc), GFP_NOFS);
1041 devlen = ubifs_encode_dev(dev, rdev);
1044 req.new_ino_d = ALIGN(devlen, 8);
1045 err = ubifs_budget_space(c, &req);
1051 err = ubifs_prepare_create(dir, dentry, &nm);
1057 sz_change = CALC_DENT_SIZE(fname_len(&nm));
1059 inode = ubifs_new_inode(c, dir, mode);
1060 if (IS_ERR(inode)) {
1062 err = PTR_ERR(inode);
1066 init_special_inode(inode, inode->i_mode, rdev);
1067 inode->i_size = ubifs_inode(inode)->ui_size = devlen;
1068 ui = ubifs_inode(inode);
1070 ui->data_len = devlen;
1072 err = ubifs_init_security(dir, inode, &dentry->d_name);
1076 mutex_lock(&dir_ui->ui_mutex);
1077 dir->i_size += sz_change;
1078 dir_ui->ui_size = dir->i_size;
1079 dir->i_mtime = dir->i_ctime = inode->i_ctime;
1080 err = ubifs_jnl_update(c, dir, &nm, inode, 0, 0);
1083 mutex_unlock(&dir_ui->ui_mutex);
1085 ubifs_release_budget(c, &req);
1086 insert_inode_hash(inode);
1087 d_instantiate(dentry, inode);
1088 fscrypt_free_filename(&nm);
1092 dir->i_size -= sz_change;
1093 dir_ui->ui_size = dir->i_size;
1094 mutex_unlock(&dir_ui->ui_mutex);
1096 make_bad_inode(inode);
1099 fscrypt_free_filename(&nm);
1101 ubifs_release_budget(c, &req);
1105 static int ubifs_symlink(struct inode *dir, struct dentry *dentry,
1106 const char *symname)
1108 struct inode *inode;
1109 struct ubifs_inode *ui;
1110 struct ubifs_inode *dir_ui = ubifs_inode(dir);
1111 struct ubifs_info *c = dir->i_sb->s_fs_info;
1112 int err, sz_change, len = strlen(symname);
1113 struct fscrypt_str disk_link;
1114 struct ubifs_budget_req req = { .new_ino = 1, .new_dent = 1,
1115 .new_ino_d = ALIGN(len, 8),
1117 struct fscrypt_name nm;
1119 dbg_gen("dent '%pd', target '%s' in dir ino %lu", dentry,
1120 symname, dir->i_ino);
1122 err = fscrypt_prepare_symlink(dir, symname, len, UBIFS_MAX_INO_DATA,
1128 * Budget request settings: new inode, new direntry and changing parent
1131 err = ubifs_budget_space(c, &req);
1135 err = ubifs_prepare_create(dir, dentry, &nm);
1139 sz_change = CALC_DENT_SIZE(fname_len(&nm));
1141 inode = ubifs_new_inode(c, dir, S_IFLNK | S_IRWXUGO);
1142 if (IS_ERR(inode)) {
1143 err = PTR_ERR(inode);
1147 ui = ubifs_inode(inode);
1148 ui->data = kmalloc(disk_link.len, GFP_NOFS);
1154 if (IS_ENCRYPTED(inode)) {
1155 disk_link.name = ui->data; /* encrypt directly into ui->data */
1156 err = fscrypt_encrypt_symlink(inode, symname, len, &disk_link);
1160 memcpy(ui->data, disk_link.name, disk_link.len);
1161 inode->i_link = ui->data;
1165 * The terminating zero byte is not written to the flash media and it
1166 * is put just to make later in-memory string processing simpler. Thus,
1167 * data length is @disk_link.len - 1, not @disk_link.len.
1169 ui->data_len = disk_link.len - 1;
1170 inode->i_size = ubifs_inode(inode)->ui_size = disk_link.len - 1;
1172 err = ubifs_init_security(dir, inode, &dentry->d_name);
1176 mutex_lock(&dir_ui->ui_mutex);
1177 dir->i_size += sz_change;
1178 dir_ui->ui_size = dir->i_size;
1179 dir->i_mtime = dir->i_ctime = inode->i_ctime;
1180 err = ubifs_jnl_update(c, dir, &nm, inode, 0, 0);
1183 mutex_unlock(&dir_ui->ui_mutex);
1185 insert_inode_hash(inode);
1186 d_instantiate(dentry, inode);
1191 dir->i_size -= sz_change;
1192 dir_ui->ui_size = dir->i_size;
1193 mutex_unlock(&dir_ui->ui_mutex);
1195 make_bad_inode(inode);
1198 fscrypt_free_filename(&nm);
1200 ubifs_release_budget(c, &req);
1205 * lock_4_inodes - a wrapper for locking three UBIFS inodes.
1206 * @inode1: first inode
1207 * @inode2: second inode
1208 * @inode3: third inode
1209 * @inode4: fouth inode
1211 * This function is used for 'ubifs_rename()' and @inode1 may be the same as
1212 * @inode2 whereas @inode3 and @inode4 may be %NULL.
1214 * We do not implement any tricks to guarantee strict lock ordering, because
1215 * VFS has already done it for us on the @i_mutex. So this is just a simple
1218 static void lock_4_inodes(struct inode *inode1, struct inode *inode2,
1219 struct inode *inode3, struct inode *inode4)
1221 mutex_lock_nested(&ubifs_inode(inode1)->ui_mutex, WB_MUTEX_1);
1222 if (inode2 != inode1)
1223 mutex_lock_nested(&ubifs_inode(inode2)->ui_mutex, WB_MUTEX_2);
1225 mutex_lock_nested(&ubifs_inode(inode3)->ui_mutex, WB_MUTEX_3);
1227 mutex_lock_nested(&ubifs_inode(inode4)->ui_mutex, WB_MUTEX_4);
1231 * unlock_4_inodes - a wrapper for unlocking three UBIFS inodes for rename.
1232 * @inode1: first inode
1233 * @inode2: second inode
1234 * @inode3: third inode
1235 * @inode4: fouth inode
1237 static void unlock_4_inodes(struct inode *inode1, struct inode *inode2,
1238 struct inode *inode3, struct inode *inode4)
1241 mutex_unlock(&ubifs_inode(inode4)->ui_mutex);
1243 mutex_unlock(&ubifs_inode(inode3)->ui_mutex);
1244 if (inode1 != inode2)
1245 mutex_unlock(&ubifs_inode(inode2)->ui_mutex);
1246 mutex_unlock(&ubifs_inode(inode1)->ui_mutex);
1249 static int do_rename(struct inode *old_dir, struct dentry *old_dentry,
1250 struct inode *new_dir, struct dentry *new_dentry,
1253 struct ubifs_info *c = old_dir->i_sb->s_fs_info;
1254 struct inode *old_inode = d_inode(old_dentry);
1255 struct inode *new_inode = d_inode(new_dentry);
1256 struct inode *whiteout = NULL;
1257 struct ubifs_inode *old_inode_ui = ubifs_inode(old_inode);
1258 struct ubifs_inode *whiteout_ui = NULL;
1259 int err, release, sync = 0, move = (new_dir != old_dir);
1260 int is_dir = S_ISDIR(old_inode->i_mode);
1261 int unlink = !!new_inode, new_sz, old_sz;
1262 struct ubifs_budget_req req = { .new_dent = 1, .mod_dent = 1,
1264 struct ubifs_budget_req ino_req = { .dirtied_ino = 1,
1265 .dirtied_ino_d = ALIGN(old_inode_ui->data_len, 8) };
1266 struct timespec64 time;
1267 unsigned int saved_nlink;
1268 struct fscrypt_name old_nm, new_nm;
1271 * Budget request settings: deletion direntry, new direntry, removing
1272 * the old inode, and changing old and new parent directory inodes.
1274 * However, this operation also marks the target inode as dirty and
1275 * does not write it, so we allocate budget for the target inode
1279 dbg_gen("dent '%pd' ino %lu in dir ino %lu to dent '%pd' in dir ino %lu flags 0x%x",
1280 old_dentry, old_inode->i_ino, old_dir->i_ino,
1281 new_dentry, new_dir->i_ino, flags);
1284 ubifs_assert(c, inode_is_locked(new_inode));
1286 err = ubifs_purge_xattrs(new_inode);
1291 if (unlink && is_dir) {
1292 err = ubifs_check_dir_empty(new_inode);
1297 err = fscrypt_setup_filename(old_dir, &old_dentry->d_name, 0, &old_nm);
1301 err = fscrypt_setup_filename(new_dir, &new_dentry->d_name, 0, &new_nm);
1303 fscrypt_free_filename(&old_nm);
1307 new_sz = CALC_DENT_SIZE(fname_len(&new_nm));
1308 old_sz = CALC_DENT_SIZE(fname_len(&old_nm));
1310 err = ubifs_budget_space(c, &req);
1312 fscrypt_free_filename(&old_nm);
1313 fscrypt_free_filename(&new_nm);
1316 err = ubifs_budget_space(c, &ino_req);
1318 fscrypt_free_filename(&old_nm);
1319 fscrypt_free_filename(&new_nm);
1320 ubifs_release_budget(c, &req);
1324 if (flags & RENAME_WHITEOUT) {
1325 union ubifs_dev_desc *dev = NULL;
1327 dev = kmalloc(sizeof(union ubifs_dev_desc), GFP_NOFS);
1333 err = do_tmpfile(old_dir, old_dentry, S_IFCHR | WHITEOUT_MODE, &whiteout);
1339 whiteout->i_state |= I_LINKABLE;
1340 whiteout_ui = ubifs_inode(whiteout);
1341 whiteout_ui->data = dev;
1342 whiteout_ui->data_len = ubifs_encode_dev(dev, MKDEV(0, 0));
1343 ubifs_assert(c, !whiteout_ui->dirty);
1346 lock_4_inodes(old_dir, new_dir, new_inode, whiteout);
1349 * Like most other Unix systems, set the @i_ctime for inodes on a
1352 time = current_time(old_dir);
1353 old_inode->i_ctime = time;
1355 /* We must adjust parent link count when renaming directories */
1359 * @old_dir loses a link because we are moving
1360 * @old_inode to a different directory.
1362 drop_nlink(old_dir);
1364 * @new_dir only gains a link if we are not also
1365 * overwriting an existing directory.
1371 * @old_inode is not moving to a different directory,
1372 * but @old_dir still loses a link if we are
1373 * overwriting an existing directory.
1376 drop_nlink(old_dir);
1380 old_dir->i_size -= old_sz;
1381 ubifs_inode(old_dir)->ui_size = old_dir->i_size;
1382 old_dir->i_mtime = old_dir->i_ctime = time;
1383 new_dir->i_mtime = new_dir->i_ctime = time;
1386 * And finally, if we unlinked a direntry which happened to have the
1387 * same name as the moved direntry, we have to decrement @i_nlink of
1388 * the unlinked inode and change its ctime.
1392 * Directories cannot have hard-links, so if this is a
1393 * directory, just clear @i_nlink.
1395 saved_nlink = new_inode->i_nlink;
1397 clear_nlink(new_inode);
1399 drop_nlink(new_inode);
1400 new_inode->i_ctime = time;
1402 new_dir->i_size += new_sz;
1403 ubifs_inode(new_dir)->ui_size = new_dir->i_size;
1407 * Do not ask 'ubifs_jnl_rename()' to flush write-buffer if @old_inode
1408 * is dirty, because this will be done later on at the end of
1411 if (IS_SYNC(old_inode)) {
1412 sync = IS_DIRSYNC(old_dir) || IS_DIRSYNC(new_dir);
1413 if (unlink && IS_SYNC(new_inode))
1418 struct ubifs_budget_req wht_req = { .dirtied_ino = 1,
1420 ALIGN(ubifs_inode(whiteout)->data_len, 8) };
1422 err = ubifs_budget_space(c, &wht_req);
1424 kfree(whiteout_ui->data);
1425 whiteout_ui->data_len = 0;
1430 inc_nlink(whiteout);
1431 mark_inode_dirty(whiteout);
1432 whiteout->i_state &= ~I_LINKABLE;
1436 err = ubifs_jnl_rename(c, old_dir, old_inode, &old_nm, new_dir,
1437 new_inode, &new_nm, whiteout, sync);
1441 unlock_4_inodes(old_dir, new_dir, new_inode, whiteout);
1442 ubifs_release_budget(c, &req);
1444 mutex_lock(&old_inode_ui->ui_mutex);
1445 release = old_inode_ui->dirty;
1446 mark_inode_dirty_sync(old_inode);
1447 mutex_unlock(&old_inode_ui->ui_mutex);
1450 ubifs_release_budget(c, &ino_req);
1451 if (IS_SYNC(old_inode))
1452 err = old_inode->i_sb->s_op->write_inode(old_inode, NULL);
1454 fscrypt_free_filename(&old_nm);
1455 fscrypt_free_filename(&new_nm);
1460 set_nlink(new_inode, saved_nlink);
1462 new_dir->i_size -= new_sz;
1463 ubifs_inode(new_dir)->ui_size = new_dir->i_size;
1465 old_dir->i_size += old_sz;
1466 ubifs_inode(old_dir)->ui_size = old_dir->i_size;
1471 drop_nlink(new_dir);
1478 drop_nlink(whiteout);
1481 unlock_4_inodes(old_dir, new_dir, new_inode, whiteout);
1483 ubifs_release_budget(c, &ino_req);
1484 ubifs_release_budget(c, &req);
1485 fscrypt_free_filename(&old_nm);
1486 fscrypt_free_filename(&new_nm);
1490 static int ubifs_xrename(struct inode *old_dir, struct dentry *old_dentry,
1491 struct inode *new_dir, struct dentry *new_dentry)
1493 struct ubifs_info *c = old_dir->i_sb->s_fs_info;
1494 struct ubifs_budget_req req = { .new_dent = 1, .mod_dent = 1,
1496 int sync = IS_DIRSYNC(old_dir) || IS_DIRSYNC(new_dir);
1497 struct inode *fst_inode = d_inode(old_dentry);
1498 struct inode *snd_inode = d_inode(new_dentry);
1499 struct timespec64 time;
1501 struct fscrypt_name fst_nm, snd_nm;
1503 ubifs_assert(c, fst_inode && snd_inode);
1505 err = fscrypt_setup_filename(old_dir, &old_dentry->d_name, 0, &fst_nm);
1509 err = fscrypt_setup_filename(new_dir, &new_dentry->d_name, 0, &snd_nm);
1511 fscrypt_free_filename(&fst_nm);
1515 lock_4_inodes(old_dir, new_dir, NULL, NULL);
1517 time = current_time(old_dir);
1518 fst_inode->i_ctime = time;
1519 snd_inode->i_ctime = time;
1520 old_dir->i_mtime = old_dir->i_ctime = time;
1521 new_dir->i_mtime = new_dir->i_ctime = time;
1523 if (old_dir != new_dir) {
1524 if (S_ISDIR(fst_inode->i_mode) && !S_ISDIR(snd_inode->i_mode)) {
1526 drop_nlink(old_dir);
1528 else if (!S_ISDIR(fst_inode->i_mode) && S_ISDIR(snd_inode->i_mode)) {
1529 drop_nlink(new_dir);
1534 err = ubifs_jnl_xrename(c, old_dir, fst_inode, &fst_nm, new_dir,
1535 snd_inode, &snd_nm, sync);
1537 unlock_4_inodes(old_dir, new_dir, NULL, NULL);
1538 ubifs_release_budget(c, &req);
1540 fscrypt_free_filename(&fst_nm);
1541 fscrypt_free_filename(&snd_nm);
1545 static int ubifs_rename(struct inode *old_dir, struct dentry *old_dentry,
1546 struct inode *new_dir, struct dentry *new_dentry,
1550 struct ubifs_info *c = old_dir->i_sb->s_fs_info;
1552 if (flags & ~(RENAME_NOREPLACE | RENAME_WHITEOUT | RENAME_EXCHANGE))
1555 ubifs_assert(c, inode_is_locked(old_dir));
1556 ubifs_assert(c, inode_is_locked(new_dir));
1558 err = fscrypt_prepare_rename(old_dir, old_dentry, new_dir, new_dentry,
1563 if (flags & RENAME_EXCHANGE)
1564 return ubifs_xrename(old_dir, old_dentry, new_dir, new_dentry);
1566 return do_rename(old_dir, old_dentry, new_dir, new_dentry, flags);
1569 int ubifs_getattr(const struct path *path, struct kstat *stat,
1570 u32 request_mask, unsigned int flags)
1573 struct inode *inode = d_inode(path->dentry);
1574 struct ubifs_inode *ui = ubifs_inode(inode);
1576 mutex_lock(&ui->ui_mutex);
1578 if (ui->flags & UBIFS_APPEND_FL)
1579 stat->attributes |= STATX_ATTR_APPEND;
1580 if (ui->flags & UBIFS_COMPR_FL)
1581 stat->attributes |= STATX_ATTR_COMPRESSED;
1582 if (ui->flags & UBIFS_CRYPT_FL)
1583 stat->attributes |= STATX_ATTR_ENCRYPTED;
1584 if (ui->flags & UBIFS_IMMUTABLE_FL)
1585 stat->attributes |= STATX_ATTR_IMMUTABLE;
1587 stat->attributes_mask |= (STATX_ATTR_APPEND |
1588 STATX_ATTR_COMPRESSED |
1589 STATX_ATTR_ENCRYPTED |
1590 STATX_ATTR_IMMUTABLE);
1592 generic_fillattr(inode, stat);
1593 stat->blksize = UBIFS_BLOCK_SIZE;
1594 stat->size = ui->ui_size;
1597 * Unfortunately, the 'stat()' system call was designed for block
1598 * device based file systems, and it is not appropriate for UBIFS,
1599 * because UBIFS does not have notion of "block". For example, it is
1600 * difficult to tell how many block a directory takes - it actually
1601 * takes less than 300 bytes, but we have to round it to block size,
1602 * which introduces large mistake. This makes utilities like 'du' to
1603 * report completely senseless numbers. This is the reason why UBIFS
1604 * goes the same way as JFFS2 - it reports zero blocks for everything
1605 * but regular files, which makes more sense than reporting completely
1608 if (S_ISREG(inode->i_mode)) {
1609 size = ui->xattr_size;
1611 size = ALIGN(size, UBIFS_BLOCK_SIZE);
1613 * Note, user-space expects 512-byte blocks count irrespectively
1614 * of what was reported in @stat->size.
1616 stat->blocks = size >> 9;
1619 mutex_unlock(&ui->ui_mutex);
1623 const struct inode_operations ubifs_dir_inode_operations = {
1624 .lookup = ubifs_lookup,
1625 .create = ubifs_create,
1627 .symlink = ubifs_symlink,
1628 .unlink = ubifs_unlink,
1629 .mkdir = ubifs_mkdir,
1630 .rmdir = ubifs_rmdir,
1631 .mknod = ubifs_mknod,
1632 .rename = ubifs_rename,
1633 .setattr = ubifs_setattr,
1634 .getattr = ubifs_getattr,
1635 .listxattr = ubifs_listxattr,
1636 .update_time = ubifs_update_time,
1637 .tmpfile = ubifs_tmpfile,
1640 const struct file_operations ubifs_dir_operations = {
1641 .llseek = generic_file_llseek,
1642 .release = ubifs_dir_release,
1643 .read = generic_read_dir,
1644 .iterate_shared = ubifs_readdir,
1645 .fsync = ubifs_fsync,
1646 .unlocked_ioctl = ubifs_ioctl,
1647 #ifdef CONFIG_COMPAT
1648 .compat_ioctl = ubifs_compat_ioctl,