Adding upstream version 6.6.15.upstream/6.6.15

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1719 insertions, 0 deletions

diff --git a/fs/ubifs/dir.c b/fs/ubifs/dir.c
new file mode 100644
index 0000000000..be45972ff9
--- /dev/null
+++ b/fs/ubifs/dir.c
@@ -0,0 +1,1719 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/* * This file is part of UBIFS.
+ *
+ * Copyright (C) 2006-2008 Nokia Corporation.
+ * Copyright (C) 2006, 2007 University of Szeged, Hungary
+ *
+ * Authors: Artem Bityutskiy (Битюцкий Артём)
+ *          Adrian Hunter
+ *          Zoltan Sogor
+ */
+
+/*
+ * This file implements directory operations.
+ *
+ * All FS operations in this file allocate budget before writing anything to the
+ * media. If they fail to allocate it, the error is returned. The only
+ * exceptions are 'ubifs_unlink()' and 'ubifs_rmdir()' which keep working even
+ * if they unable to allocate the budget, because deletion %-ENOSPC failure is
+ * not what users are usually ready to get. UBIFS budgeting subsystem has some
+ * space reserved for these purposes.
+ *
+ * All operations in this file write all inodes which they change straight
+ * away, instead of marking them dirty. For example, 'ubifs_link()' changes
+ * @i_size of the parent inode and writes the parent inode together with the
+ * target inode. This was done to simplify file-system recovery which would
+ * otherwise be very difficult to do. The only exception is rename which marks
+ * the re-named inode dirty (because its @i_ctime is updated) but does not
+ * write it, but just marks it as dirty.
+ */
+
+#include "ubifs.h"
+
+/**
+ * inherit_flags - inherit flags of the parent inode.
+ * @dir: parent inode
+ * @mode: new inode mode flags
+ *
+ * This is a helper function for 'ubifs_new_inode()' which inherits flag of the
+ * parent directory inode @dir. UBIFS inodes inherit the following flags:
+ * o %UBIFS_COMPR_FL, which is useful to switch compression on/of on
+ *   sub-directory basis;
+ * o %UBIFS_SYNC_FL - useful for the same reasons;
+ * o %UBIFS_DIRSYNC_FL - similar, but relevant only to directories.
+ *
+ * This function returns the inherited flags.
+ */
+static int inherit_flags(const struct inode *dir, umode_t mode)
+{
+	int flags;
+	const struct ubifs_inode *ui = ubifs_inode(dir);
+
+	if (!S_ISDIR(dir->i_mode))
+		/*
+		 * The parent is not a directory, which means that an extended
+		 * attribute inode is being created. No flags.
+		 */
+		return 0;
+
+	flags = ui->flags & (UBIFS_COMPR_FL | UBIFS_SYNC_FL | UBIFS_DIRSYNC_FL);
+	if (!S_ISDIR(mode))
+		/* The "DIRSYNC" flag only applies to directories */
+		flags &= ~UBIFS_DIRSYNC_FL;
+	return flags;
+}
+
+/**
+ * ubifs_new_inode - allocate new UBIFS inode object.
+ * @c: UBIFS file-system description object
+ * @dir: parent directory inode
+ * @mode: inode mode flags
+ * @is_xattr: whether the inode is xattr inode
+ *
+ * This function finds an unused inode number, allocates new inode and
+ * initializes it. Returns new inode in case of success and an error code in
+ * case of failure.
+ */
+struct inode *ubifs_new_inode(struct ubifs_info *c, struct inode *dir,
+			      umode_t mode, bool is_xattr)
+{
+	int err;
+	struct inode *inode;
+	struct ubifs_inode *ui;
+	bool encrypted = false;
+
+	inode = new_inode(c->vfs_sb);
+	ui = ubifs_inode(inode);
+	if (!inode)
+		return ERR_PTR(-ENOMEM);
+
+	/*
+	 * Set 'S_NOCMTIME' to prevent VFS form updating [mc]time of inodes and
+	 * marking them dirty in file write path (see 'file_update_time()').
+	 * UBIFS has to fully control "clean <-> dirty" transitions of inodes
+	 * to make budgeting work.
+	 */
+	inode->i_flags |= S_NOCMTIME;
+
+	inode_init_owner(&nop_mnt_idmap, inode, dir, mode);
+	inode->i_mtime = inode->i_atime = inode_set_ctime_current(inode);
+	inode->i_mapping->nrpages = 0;
+
+	if (!is_xattr) {
+		err = fscrypt_prepare_new_inode(dir, inode, &encrypted);
+		if (err) {
+			ubifs_err(c, "fscrypt_prepare_new_inode failed: %i", err);
+			goto out_iput;
+		}
+	}
+
+	switch (mode & S_IFMT) {
+	case S_IFREG:
+		inode->i_mapping->a_ops = &ubifs_file_address_operations;
+		inode->i_op = &ubifs_file_inode_operations;
+		inode->i_fop = &ubifs_file_operations;
+		break;
+	case S_IFDIR:
+		inode->i_op  = &ubifs_dir_inode_operations;
+		inode->i_fop = &ubifs_dir_operations;
+		inode->i_size = ui->ui_size = UBIFS_INO_NODE_SZ;
+		break;
+	case S_IFLNK:
+		inode->i_op = &ubifs_symlink_inode_operations;
+		break;
+	case S_IFSOCK:
+	case S_IFIFO:
+	case S_IFBLK:
+	case S_IFCHR:
+		inode->i_op  = &ubifs_file_inode_operations;
+		break;
+	default:
+		BUG();
+	}
+
+	ui->flags = inherit_flags(dir, mode);
+	ubifs_set_inode_flags(inode);
+	if (S_ISREG(mode))
+		ui->compr_type = c->default_compr;
+	else
+		ui->compr_type = UBIFS_COMPR_NONE;
+	ui->synced_i_size = 0;
+
+	spin_lock(&c->cnt_lock);
+	/* Inode number overflow is currently not supported */
+	if (c->highest_inum >= INUM_WARN_WATERMARK) {
+		if (c->highest_inum >= INUM_WATERMARK) {
+			spin_unlock(&c->cnt_lock);
+			ubifs_err(c, "out of inode numbers");
+			err = -EINVAL;
+			goto out_iput;
+		}
+		ubifs_warn(c, "running out of inode numbers (current %lu, max %u)",
+			   (unsigned long)c->highest_inum, INUM_WATERMARK);
+	}
+
+	inode->i_ino = ++c->highest_inum;
+	/*
+	 * The creation sequence number remains with this inode for its
+	 * lifetime. All nodes for this inode have a greater sequence number,
+	 * and so it is possible to distinguish obsolete nodes belonging to a
+	 * previous incarnation of the same inode number - for example, for the
+	 * purpose of rebuilding the index.
+	 */
+	ui->creat_sqnum = ++c->max_sqnum;
+	spin_unlock(&c->cnt_lock);
+
+	if (encrypted) {
+		err = fscrypt_set_context(inode, NULL);
+		if (err) {
+			ubifs_err(c, "fscrypt_set_context failed: %i", err);
+			goto out_iput;
+		}
+	}
+
+	return inode;
+
+out_iput:
+	make_bad_inode(inode);
+	iput(inode);
+	return ERR_PTR(err);
+}
+
+static int dbg_check_name(const struct ubifs_info *c,
+			  const struct ubifs_dent_node *dent,
+			  const struct fscrypt_name *nm)
+{
+	if (!dbg_is_chk_gen(c))
+		return 0;
+	if (le16_to_cpu(dent->nlen) != fname_len(nm))
+		return -EINVAL;
+	if (memcmp(dent->name, fname_name(nm), fname_len(nm)))
+		return -EINVAL;
+	return 0;
+}
+
+static struct dentry *ubifs_lookup(struct inode *dir, struct dentry *dentry,
+				   unsigned int flags)
+{
+	int err;
+	union ubifs_key key;
+	struct inode *inode = NULL;
+	struct ubifs_dent_node *dent = NULL;
+	struct ubifs_info *c = dir->i_sb->s_fs_info;
+	struct fscrypt_name nm;
+
+	dbg_gen("'%pd' in dir ino %lu", dentry, dir->i_ino);
+
+	err = fscrypt_prepare_lookup(dir, dentry, &nm);
+	generic_set_encrypted_ci_d_ops(dentry);
+	if (err == -ENOENT)
+		return d_splice_alias(NULL, dentry);
+	if (err)
+		return ERR_PTR(err);
+
+	if (fname_len(&nm) > UBIFS_MAX_NLEN) {
+		inode = ERR_PTR(-ENAMETOOLONG);
+		goto done;
+	}
+
+	dent = kmalloc(UBIFS_MAX_DENT_NODE_SZ, GFP_NOFS);
+	if (!dent) {
+		inode = ERR_PTR(-ENOMEM);
+		goto done;
+	}
+
+	if (fname_name(&nm) == NULL) {
+		if (nm.hash & ~UBIFS_S_KEY_HASH_MASK)
+			goto done; /* ENOENT */
+		dent_key_init_hash(c, &key, dir->i_ino, nm.hash);
+		err = ubifs_tnc_lookup_dh(c, &key, dent, nm.minor_hash);
+	} else {
+		dent_key_init(c, &key, dir->i_ino, &nm);
+		err = ubifs_tnc_lookup_nm(c, &key, dent, &nm);
+	}
+
+	if (err) {
+		if (err == -ENOENT)
+			dbg_gen("not found");
+		else
+			inode = ERR_PTR(err);
+		goto done;
+	}
+
+	if (dbg_check_name(c, dent, &nm)) {
+		inode = ERR_PTR(-EINVAL);
+		goto done;
+	}
+
+	inode = ubifs_iget(dir->i_sb, le64_to_cpu(dent->inum));
+	if (IS_ERR(inode)) {
+		/*
+		 * This should not happen. Probably the file-system needs
+		 * checking.
+		 */
+		err = PTR_ERR(inode);
+		ubifs_err(c, "dead directory entry '%pd', error %d",
+			  dentry, err);
+		ubifs_ro_mode(c, err);
+		goto done;
+	}
+
+	if (IS_ENCRYPTED(dir) &&
+	    (S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode)) &&
+	    !fscrypt_has_permitted_context(dir, inode)) {
+		ubifs_warn(c, "Inconsistent encryption contexts: %lu/%lu",
+			   dir->i_ino, inode->i_ino);
+		iput(inode);
+		inode = ERR_PTR(-EPERM);
+	}
+
+done:
+	kfree(dent);
+	fscrypt_free_filename(&nm);
+	return d_splice_alias(inode, dentry);
+}
+
+static int ubifs_prepare_create(struct inode *dir, struct dentry *dentry,
+				struct fscrypt_name *nm)
+{
+	if (fscrypt_is_nokey_name(dentry))
+		return -ENOKEY;
+
+	return fscrypt_setup_filename(dir, &dentry->d_name, 0, nm);
+}
+
+static int ubifs_create(struct mnt_idmap *idmap, struct inode *dir,
+			struct dentry *dentry, umode_t mode, bool excl)
+{
+	struct inode *inode;
+	struct ubifs_info *c = dir->i_sb->s_fs_info;
+	struct ubifs_budget_req req = { .new_ino = 1, .new_dent = 1,
+					.dirtied_ino = 1 };
+	struct ubifs_inode *dir_ui = ubifs_inode(dir);
+	struct fscrypt_name nm;
+	int err, sz_change;
+
+	/*
+	 * Budget request settings: new inode, new direntry, changing the
+	 * parent directory inode.
+	 */
+
+	dbg_gen("dent '%pd', mode %#hx in dir ino %lu",
+		dentry, mode, dir->i_ino);
+
+	err = ubifs_budget_space(c, &req);
+	if (err)
+		return err;
+
+	err = ubifs_prepare_create(dir, dentry, &nm);
+	if (err)
+		goto out_budg;
+
+	sz_change = CALC_DENT_SIZE(fname_len(&nm));
+
+	inode = ubifs_new_inode(c, dir, mode, false);
+	if (IS_ERR(inode)) {
+		err = PTR_ERR(inode);
+		goto out_fname;
+	}
+
+	err = ubifs_init_security(dir, inode, &dentry->d_name);
+	if (err)
+		goto out_inode;
+
+	mutex_lock(&dir_ui->ui_mutex);
+	dir->i_size += sz_change;
+	dir_ui->ui_size = dir->i_size;
+	dir->i_mtime = inode_set_ctime_to_ts(dir, inode_get_ctime(inode));
+	err = ubifs_jnl_update(c, dir, &nm, inode, 0, 0);
+	if (err)
+		goto out_cancel;
+	mutex_unlock(&dir_ui->ui_mutex);
+
+	ubifs_release_budget(c, &req);
+	fscrypt_free_filename(&nm);
+	insert_inode_hash(inode);
+	d_instantiate(dentry, inode);
+	return 0;
+
+out_cancel:
+	dir->i_size -= sz_change;
+	dir_ui->ui_size = dir->i_size;
+	mutex_unlock(&dir_ui->ui_mutex);
+out_inode:
+	make_bad_inode(inode);
+	iput(inode);
+out_fname:
+	fscrypt_free_filename(&nm);
+out_budg:
+	ubifs_release_budget(c, &req);
+	ubifs_err(c, "cannot create regular file, error %d", err);
+	return err;
+}
+
+static struct inode *create_whiteout(struct inode *dir, struct dentry *dentry)
+{
+	int err;
+	umode_t mode = S_IFCHR | WHITEOUT_MODE;
+	struct inode *inode;
+	struct ubifs_info *c = dir->i_sb->s_fs_info;
+
+	/*
+	 * Create an inode('nlink = 1') for whiteout without updating journal,
+	 * let ubifs_jnl_rename() store it on flash to complete rename whiteout
+	 * atomically.
+	 */
+
+	dbg_gen("dent '%pd', mode %#hx in dir ino %lu",
+		dentry, mode, dir->i_ino);
+
+	inode = ubifs_new_inode(c, dir, mode, false);
+	if (IS_ERR(inode)) {
+		err = PTR_ERR(inode);
+		goto out_free;
+	}
+
+	init_special_inode(inode, inode->i_mode, WHITEOUT_DEV);
+	ubifs_assert(c, inode->i_op == &ubifs_file_inode_operations);
+
+	err = ubifs_init_security(dir, inode, &dentry->d_name);
+	if (err)
+		goto out_inode;
+
+	/* The dir size is updated by do_rename. */
+	insert_inode_hash(inode);
+
+	return inode;
+
+out_inode:
+	make_bad_inode(inode);
+	iput(inode);
+out_free:
+	ubifs_err(c, "cannot create whiteout file, error %d", err);
+	return ERR_PTR(err);
+}
+
+/**
+ * lock_2_inodes - a wrapper for locking two UBIFS inodes.
+ * @inode1: first inode
+ * @inode2: second inode
+ *
+ * We do not implement any tricks to guarantee strict lock ordering, because
+ * VFS has already done it for us on the @i_mutex. So this is just a simple
+ * wrapper function.
+ */
+static void lock_2_inodes(struct inode *inode1, struct inode *inode2)
+{
+	mutex_lock_nested(&ubifs_inode(inode1)->ui_mutex, WB_MUTEX_1);
+	mutex_lock_nested(&ubifs_inode(inode2)->ui_mutex, WB_MUTEX_2);
+}
+
+/**
+ * unlock_2_inodes - a wrapper for unlocking two UBIFS inodes.
+ * @inode1: first inode
+ * @inode2: second inode
+ */
+static void unlock_2_inodes(struct inode *inode1, struct inode *inode2)
+{
+	mutex_unlock(&ubifs_inode(inode2)->ui_mutex);
+	mutex_unlock(&ubifs_inode(inode1)->ui_mutex);
+}
+
+static int ubifs_tmpfile(struct mnt_idmap *idmap, struct inode *dir,
+			 struct file *file, umode_t mode)
+{
+	struct dentry *dentry = file->f_path.dentry;
+	struct inode *inode;
+	struct ubifs_info *c = dir->i_sb->s_fs_info;
+	struct ubifs_budget_req req = { .new_ino = 1, .new_dent = 1,
+					.dirtied_ino = 1};
+	struct ubifs_budget_req ino_req = { .dirtied_ino = 1 };
+	struct ubifs_inode *ui;
+	int err, instantiated = 0;
+	struct fscrypt_name nm;
+
+	/*
+	 * Budget request settings: new inode, new direntry, changing the
+	 * parent directory inode.
+	 * Allocate budget separately for new dirtied inode, the budget will
+	 * be released via writeback.
+	 */
+
+	dbg_gen("dent '%pd', mode %#hx in dir ino %lu",
+		dentry, mode, dir->i_ino);
+
+	err = fscrypt_setup_filename(dir, &dentry->d_name, 0, &nm);
+	if (err)
+		return err;
+
+	err = ubifs_budget_space(c, &req);
+	if (err) {
+		fscrypt_free_filename(&nm);
+		return err;
+	}
+
+	err = ubifs_budget_space(c, &ino_req);
+	if (err) {
+		ubifs_release_budget(c, &req);
+		fscrypt_free_filename(&nm);
+		return err;
+	}
+
+	inode = ubifs_new_inode(c, dir, mode, false);
+	if (IS_ERR(inode)) {
+		err = PTR_ERR(inode);
+		goto out_budg;
+	}
+	ui = ubifs_inode(inode);
+
+	err = ubifs_init_security(dir, inode, &dentry->d_name);
+	if (err)
+		goto out_inode;
+
+	mutex_lock(&ui->ui_mutex);
+	insert_inode_hash(inode);
+	d_tmpfile(file, inode);
+	ubifs_assert(c, ui->dirty);
+
+	instantiated = 1;
+	mutex_unlock(&ui->ui_mutex);
+
+	lock_2_inodes(dir, inode);
+	err = ubifs_jnl_update(c, dir, &nm, inode, 1, 0);
+	if (err)
+		goto out_cancel;
+	unlock_2_inodes(dir, inode);
+
+	ubifs_release_budget(c, &req);
+	fscrypt_free_filename(&nm);
+
+	return finish_open_simple(file, 0);
+
+out_cancel:
+	unlock_2_inodes(dir, inode);
+out_inode:
+	make_bad_inode(inode);
+	if (!instantiated)
+		iput(inode);
+out_budg:
+	ubifs_release_budget(c, &req);
+	if (!instantiated)
+		ubifs_release_budget(c, &ino_req);
+	fscrypt_free_filename(&nm);
+	ubifs_err(c, "cannot create temporary file, error %d", err);
+	return err;
+}
+
+/**
+ * vfs_dent_type - get VFS directory entry type.
+ * @type: UBIFS directory entry type
+ *
+ * This function converts UBIFS directory entry type into VFS directory entry
+ * type.
+ */
+static unsigned int vfs_dent_type(uint8_t type)
+{
+	switch (type) {
+	case UBIFS_ITYPE_REG:
+		return DT_REG;
+	case UBIFS_ITYPE_DIR:
+		return DT_DIR;
+	case UBIFS_ITYPE_LNK:
+		return DT_LNK;
+	case UBIFS_ITYPE_BLK:
+		return DT_BLK;
+	case UBIFS_ITYPE_CHR:
+		return DT_CHR;
+	case UBIFS_ITYPE_FIFO:
+		return DT_FIFO;
+	case UBIFS_ITYPE_SOCK:
+		return DT_SOCK;
+	default:
+		BUG();
+	}
+	return 0;
+}
+
+/*
+ * The classical Unix view for directory is that it is a linear array of
+ * (name, inode number) entries. Linux/VFS assumes this model as well.
+ * Particularly, 'readdir()' call wants us to return a directory entry offset
+ * which later may be used to continue 'readdir()'ing the directory or to
+ * 'seek()' to that specific direntry. Obviously UBIFS does not really fit this
+ * model because directory entries are identified by keys, which may collide.
+ *
+ * UBIFS uses directory entry hash value for directory offsets, so
+ * 'seekdir()'/'telldir()' may not always work because of possible key
+ * collisions. But UBIFS guarantees that consecutive 'readdir()' calls work
+ * properly by means of saving full directory entry name in the private field
+ * of the file description object.
+ *
+ * This means that UBIFS cannot support NFS which requires full
+ * 'seekdir()'/'telldir()' support.
+ */
+static int ubifs_readdir(struct file *file, struct dir_context *ctx)
+{
+	int fstr_real_len = 0, err = 0;
+	struct fscrypt_name nm;
+	struct fscrypt_str fstr = {0};
+	union ubifs_key key;
+	struct ubifs_dent_node *dent;
+	struct inode *dir = file_inode(file);
+	struct ubifs_info *c = dir->i_sb->s_fs_info;
+	bool encrypted = IS_ENCRYPTED(dir);
+
+	dbg_gen("dir ino %lu, f_pos %#llx", dir->i_ino, ctx->pos);
+
+	if (ctx->pos > UBIFS_S_KEY_HASH_MASK || ctx->pos == 2)
+		/*
+		 * The directory was seek'ed to a senseless position or there
+		 * are no more entries.
+		 */
+		return 0;
+
+	if (encrypted) {
+		err = fscrypt_prepare_readdir(dir);
+		if (err)
+			return err;
+
+		err = fscrypt_fname_alloc_buffer(UBIFS_MAX_NLEN, &fstr);
+		if (err)
+			return err;
+
+		fstr_real_len = fstr.len;
+	}
+
+	if (file->f_version == 0) {
+		/*
+		 * The file was seek'ed, which means that @file->private_data
+		 * is now invalid. This may also be just the first
+		 * 'ubifs_readdir()' invocation, in which case
+		 * @file->private_data is NULL, and the below code is
+		 * basically a no-op.
+		 */
+		kfree(file->private_data);
+		file->private_data = NULL;
+	}
+
+	/*
+	 * 'generic_file_llseek()' unconditionally sets @file->f_version to
+	 * zero, and we use this for detecting whether the file was seek'ed.
+	 */
+	file->f_version = 1;
+
+	/* File positions 0 and 1 correspond to "." and ".." */
+	if (ctx->pos < 2) {
+		ubifs_assert(c, !file->private_data);
+		if (!dir_emit_dots(file, ctx)) {
+			if (encrypted)
+				fscrypt_fname_free_buffer(&fstr);
+			return 0;
+		}
+
+		/* Find the first entry in TNC and save it */
+		lowest_dent_key(c, &key, dir->i_ino);
+		fname_len(&nm) = 0;
+		dent = ubifs_tnc_next_ent(c, &key, &nm);
+		if (IS_ERR(dent)) {
+			err = PTR_ERR(dent);
+			goto out;
+		}
+
+		ctx->pos = key_hash_flash(c, &dent->key);
+		file->private_data = dent;
+	}
+
+	dent = file->private_data;
+	if (!dent) {
+		/*
+		 * The directory was seek'ed to and is now readdir'ed.
+		 * Find the entry corresponding to @ctx->pos or the closest one.
+		 */
+		dent_key_init_hash(c, &key, dir->i_ino, ctx->pos);
+		fname_len(&nm) = 0;
+		dent = ubifs_tnc_next_ent(c, &key, &nm);
+		if (IS_ERR(dent)) {
+			err = PTR_ERR(dent);
+			goto out;
+		}
+		ctx->pos = key_hash_flash(c, &dent->key);
+		file->private_data = dent;
+	}
+
+	while (1) {
+		dbg_gen("ino %llu, new f_pos %#x",
+			(unsigned long long)le64_to_cpu(dent->inum),
+			key_hash_flash(c, &dent->key));
+		ubifs_assert(c, le64_to_cpu(dent->ch.sqnum) >
+			     ubifs_inode(dir)->creat_sqnum);
+
+		fname_len(&nm) = le16_to_cpu(dent->nlen);
+		fname_name(&nm) = dent->name;
+
+		if (encrypted) {
+			fstr.len = fstr_real_len;
+
+			err = fscrypt_fname_disk_to_usr(dir, key_hash_flash(c,
+							&dent->key),
+							le32_to_cpu(dent->cookie),
+							&nm.disk_name, &fstr);
+			if (err)
+				goto out;
+		} else {
+			fstr.len = fname_len(&nm);
+			fstr.name = fname_name(&nm);
+		}
+
+		if (!dir_emit(ctx, fstr.name, fstr.len,
+			       le64_to_cpu(dent->inum),
+			       vfs_dent_type(dent->type))) {
+			if (encrypted)
+				fscrypt_fname_free_buffer(&fstr);
+			return 0;
+		}
+
+		/* Switch to the next entry */
+		key_read(c, &dent->key, &key);
+		dent = ubifs_tnc_next_ent(c, &key, &nm);
+		if (IS_ERR(dent)) {
+			err = PTR_ERR(dent);
+			goto out;
+		}
+
+		kfree(file->private_data);
+		ctx->pos = key_hash_flash(c, &dent->key);
+		file->private_data = dent;
+		cond_resched();
+	}
+
+out:
+	kfree(file->private_data);
+	file->private_data = NULL;
+
+	if (encrypted)
+		fscrypt_fname_free_buffer(&fstr);
+
+	if (err != -ENOENT)
+		ubifs_err(c, "cannot find next direntry, error %d", err);
+	else
+		/*
+		 * -ENOENT is a non-fatal error in this context, the TNC uses
+		 * it to indicate that the cursor moved past the current directory
+		 * and readdir() has to stop.
+		 */
+		err = 0;
+
+
+	/* 2 is a special value indicating that there are no more direntries */
+	ctx->pos = 2;
+	return err;
+}
+
+/* Free saved readdir() state when the directory is closed */
+static int ubifs_dir_release(struct inode *dir, struct file *file)
+{
+	kfree(file->private_data);
+	file->private_data = NULL;
+	return 0;
+}
+
+static int ubifs_link(struct dentry *old_dentry, struct inode *dir,
+		      struct dentry *dentry)
+{
+	struct ubifs_info *c = dir->i_sb->s_fs_info;
+	struct inode *inode = d_inode(old_dentry);
+	struct ubifs_inode *ui = ubifs_inode(inode);
+	struct ubifs_inode *dir_ui = ubifs_inode(dir);
+	int err, sz_change = CALC_DENT_SIZE(dentry->d_name.len);
+	struct ubifs_budget_req req = { .new_dent = 1, .dirtied_ino = 2,
+				.dirtied_ino_d = ALIGN(ui->data_len, 8) };
+	struct fscrypt_name nm;
+
+	/*
+	 * Budget request settings: new direntry, changing the target inode,
+	 * changing the parent inode.
+	 */
+
+	dbg_gen("dent '%pd' to ino %lu (nlink %d) in dir ino %lu",
+		dentry, inode->i_ino,
+		inode->i_nlink, dir->i_ino);
+	ubifs_assert(c, inode_is_locked(dir));
+	ubifs_assert(c, inode_is_locked(inode));
+
+	err = fscrypt_prepare_link(old_dentry, dir, dentry);
+	if (err)
+		return err;
+
+	err = fscrypt_setup_filename(dir, &dentry->d_name, 0, &nm);
+	if (err)
+		return err;
+
+	err = dbg_check_synced_i_size(c, inode);
+	if (err)
+		goto out_fname;
+
+	err = ubifs_budget_space(c, &req);
+	if (err)
+		goto out_fname;
+
+	lock_2_inodes(dir, inode);
+
+	/* Handle O_TMPFILE corner case, it is allowed to link a O_TMPFILE. */
+	if (inode->i_nlink == 0)
+		ubifs_delete_orphan(c, inode->i_ino);
+
+	inc_nlink(inode);
+	ihold(inode);
+	inode_set_ctime_current(inode);
+	dir->i_size += sz_change;
+	dir_ui->ui_size = dir->i_size;
+	dir->i_mtime = inode_set_ctime_to_ts(dir, inode_get_ctime(inode));
+	err = ubifs_jnl_update(c, dir, &nm, inode, 0, 0);
+	if (err)
+		goto out_cancel;
+	unlock_2_inodes(dir, inode);
+
+	ubifs_release_budget(c, &req);
+	d_instantiate(dentry, inode);
+	fscrypt_free_filename(&nm);
+	return 0;
+
+out_cancel:
+	dir->i_size -= sz_change;
+	dir_ui->ui_size = dir->i_size;
+	drop_nlink(inode);
+	if (inode->i_nlink == 0)
+		ubifs_add_orphan(c, inode->i_ino);
+	unlock_2_inodes(dir, inode);
+	ubifs_release_budget(c, &req);
+	iput(inode);
+out_fname:
+	fscrypt_free_filename(&nm);
+	return err;
+}
+
+static int ubifs_unlink(struct inode *dir, struct dentry *dentry)
+{
+	struct ubifs_info *c = dir->i_sb->s_fs_info;
+	struct inode *inode = d_inode(dentry);
+	struct ubifs_inode *dir_ui = ubifs_inode(dir);
+	int err, sz_change, budgeted = 1;
+	struct ubifs_budget_req req = { .mod_dent = 1, .dirtied_ino = 2 };
+	unsigned int saved_nlink = inode->i_nlink;
+	struct fscrypt_name nm;
+
+	/*
+	 * Budget request settings: deletion direntry, deletion inode (+1 for
+	 * @dirtied_ino), changing the parent directory inode. If budgeting
+	 * fails, go ahead anyway because we have extra space reserved for
+	 * deletions.
+	 */
+
+	dbg_gen("dent '%pd' from ino %lu (nlink %d) in dir ino %lu",
+		dentry, inode->i_ino,
+		inode->i_nlink, dir->i_ino);
+
+	err = fscrypt_setup_filename(dir, &dentry->d_name, 1, &nm);
+	if (err)
+		return err;
+
+	err = ubifs_purge_xattrs(inode);
+	if (err)
+		return err;
+
+	sz_change = CALC_DENT_SIZE(fname_len(&nm));
+
+	ubifs_assert(c, inode_is_locked(dir));
+	ubifs_assert(c, inode_is_locked(inode));
+	err = dbg_check_synced_i_size(c, inode);
+	if (err)
+		goto out_fname;
+
+	err = ubifs_budget_space(c, &req);
+	if (err) {
+		if (err != -ENOSPC)
+			goto out_fname;
+		budgeted = 0;
+	}
+
+	lock_2_inodes(dir, inode);
+	inode_set_ctime_current(inode);
+	drop_nlink(inode);
+	dir->i_size -= sz_change;
+	dir_ui->ui_size = dir->i_size;
+	dir->i_mtime = inode_set_ctime_to_ts(dir, inode_get_ctime(inode));
+	err = ubifs_jnl_update(c, dir, &nm, inode, 1, 0);
+	if (err)
+		goto out_cancel;
+	unlock_2_inodes(dir, inode);
+
+	if (budgeted)
+		ubifs_release_budget(c, &req);
+	else {
+		/* We've deleted something - clean the "no space" flags */
+		c->bi.nospace = c->bi.nospace_rp = 0;
+		smp_wmb();
+	}
+	fscrypt_free_filename(&nm);
+	return 0;
+
+out_cancel:
+	dir->i_size += sz_change;
+	dir_ui->ui_size = dir->i_size;
+	set_nlink(inode, saved_nlink);
+	unlock_2_inodes(dir, inode);
+	if (budgeted)
+		ubifs_release_budget(c, &req);
+out_fname:
+	fscrypt_free_filename(&nm);
+	return err;
+}
+
+/**
+ * ubifs_check_dir_empty - check if a directory is empty or not.
+ * @dir: VFS inode object of the directory to check
+ *
+ * This function checks if directory @dir is empty. Returns zero if the
+ * directory is empty, %-ENOTEMPTY if it is not, and other negative error codes
+ * in case of errors.
+ */
+int ubifs_check_dir_empty(struct inode *dir)
+{
+	struct ubifs_info *c = dir->i_sb->s_fs_info;
+	struct fscrypt_name nm = { 0 };
+	struct ubifs_dent_node *dent;
+	union ubifs_key key;
+	int err;
+
+	lowest_dent_key(c, &key, dir->i_ino);
+	dent = ubifs_tnc_next_ent(c, &key, &nm);
+	if (IS_ERR(dent)) {
+		err = PTR_ERR(dent);
+		if (err == -ENOENT)
+			err = 0;
+	} else {
+		kfree(dent);
+		err = -ENOTEMPTY;
+	}
+	return err;
+}
+
+static int ubifs_rmdir(struct inode *dir, struct dentry *dentry)
+{
+	struct ubifs_info *c = dir->i_sb->s_fs_info;
+	struct inode *inode = d_inode(dentry);
+	int err, sz_change, budgeted = 1;
+	struct ubifs_inode *dir_ui = ubifs_inode(dir);
+	struct ubifs_budget_req req = { .mod_dent = 1, .dirtied_ino = 2 };
+	struct fscrypt_name nm;
+
+	/*
+	 * Budget request settings: deletion direntry, deletion inode and
+	 * changing the parent inode. If budgeting fails, go ahead anyway
+	 * because we have extra space reserved for deletions.
+	 */
+
+	dbg_gen("directory '%pd', ino %lu in dir ino %lu", dentry,
+		inode->i_ino, dir->i_ino);
+	ubifs_assert(c, inode_is_locked(dir));
+	ubifs_assert(c, inode_is_locked(inode));
+	err = ubifs_check_dir_empty(d_inode(dentry));
+	if (err)
+		return err;
+
+	err = fscrypt_setup_filename(dir, &dentry->d_name, 1, &nm);
+	if (err)
+		return err;
+
+	err = ubifs_purge_xattrs(inode);
+	if (err)
+		return err;
+
+	sz_change = CALC_DENT_SIZE(fname_len(&nm));
+
+	err = ubifs_budget_space(c, &req);
+	if (err) {
+		if (err != -ENOSPC)
+			goto out_fname;
+		budgeted = 0;
+	}
+
+	lock_2_inodes(dir, inode);
+	inode_set_ctime_current(inode);
+	clear_nlink(inode);
+	drop_nlink(dir);
+	dir->i_size -= sz_change;
+	dir_ui->ui_size = dir->i_size;
+	dir->i_mtime = inode_set_ctime_to_ts(dir, inode_get_ctime(inode));
+	err = ubifs_jnl_update(c, dir, &nm, inode, 1, 0);
+	if (err)
+		goto out_cancel;
+	unlock_2_inodes(dir, inode);
+
+	if (budgeted)
+		ubifs_release_budget(c, &req);
+	else {
+		/* We've deleted something - clean the "no space" flags */
+		c->bi.nospace = c->bi.nospace_rp = 0;
+		smp_wmb();
+	}
+	fscrypt_free_filename(&nm);
+	return 0;
+
+out_cancel:
+	dir->i_size += sz_change;
+	dir_ui->ui_size = dir->i_size;
+	inc_nlink(dir);
+	set_nlink(inode, 2);
+	unlock_2_inodes(dir, inode);
+	if (budgeted)
+		ubifs_release_budget(c, &req);
+out_fname:
+	fscrypt_free_filename(&nm);
+	return err;
+}
+
+static int ubifs_mkdir(struct mnt_idmap *idmap, struct inode *dir,
+		       struct dentry *dentry, umode_t mode)
+{
+	struct inode *inode;
+	struct ubifs_inode *dir_ui = ubifs_inode(dir);
+	struct ubifs_info *c = dir->i_sb->s_fs_info;
+	int err, sz_change;
+	struct ubifs_budget_req req = { .new_ino = 1, .new_dent = 1,
+					.dirtied_ino = 1};
+	struct fscrypt_name nm;
+
+	/*
+	 * Budget request settings: new inode, new direntry and changing parent
+	 * directory inode.
+	 */
+
+	dbg_gen("dent '%pd', mode %#hx in dir ino %lu",
+		dentry, mode, dir->i_ino);
+
+	err = ubifs_budget_space(c, &req);
+	if (err)
+		return err;
+
+	err = ubifs_prepare_create(dir, dentry, &nm);
+	if (err)
+		goto out_budg;
+
+	sz_change = CALC_DENT_SIZE(fname_len(&nm));
+
+	inode = ubifs_new_inode(c, dir, S_IFDIR | mode, false);
+	if (IS_ERR(inode)) {
+		err = PTR_ERR(inode);
+		goto out_fname;
+	}
+
+	err = ubifs_init_security(dir, inode, &dentry->d_name);
+	if (err)
+		goto out_inode;
+
+	mutex_lock(&dir_ui->ui_mutex);
+	insert_inode_hash(inode);
+	inc_nlink(inode);
+	inc_nlink(dir);
+	dir->i_size += sz_change;
+	dir_ui->ui_size = dir->i_size;
+	dir->i_mtime = inode_set_ctime_to_ts(dir, inode_get_ctime(inode));
+	err = ubifs_jnl_update(c, dir, &nm, inode, 0, 0);
+	if (err) {
+		ubifs_err(c, "cannot create directory, error %d", err);
+		goto out_cancel;
+	}
+	mutex_unlock(&dir_ui->ui_mutex);
+
+	ubifs_release_budget(c, &req);
+	d_instantiate(dentry, inode);
+	fscrypt_free_filename(&nm);
+	return 0;
+
+out_cancel:
+	dir->i_size -= sz_change;
+	dir_ui->ui_size = dir->i_size;
+	drop_nlink(dir);
+	mutex_unlock(&dir_ui->ui_mutex);
+out_inode:
+	make_bad_inode(inode);
+	iput(inode);
+out_fname:
+	fscrypt_free_filename(&nm);
+out_budg:
+	ubifs_release_budget(c, &req);
+	return err;
+}
+
+static int ubifs_mknod(struct mnt_idmap *idmap, struct inode *dir,
+		       struct dentry *dentry, umode_t mode, dev_t rdev)
+{
+	struct inode *inode;
+	struct ubifs_inode *ui;
+	struct ubifs_inode *dir_ui = ubifs_inode(dir);
+	struct ubifs_info *c = dir->i_sb->s_fs_info;
+	union ubifs_dev_desc *dev = NULL;
+	int sz_change;
+	int err, devlen = 0;
+	struct ubifs_budget_req req = { .new_ino = 1, .new_dent = 1,
+					.dirtied_ino = 1 };
+	struct fscrypt_name nm;
+
+	/*
+	 * Budget request settings: new inode, new direntry and changing parent
+	 * directory inode.
+	 */
+
+	dbg_gen("dent '%pd' in dir ino %lu", dentry, dir->i_ino);
+
+	if (S_ISBLK(mode) || S_ISCHR(mode)) {
+		dev = kmalloc(sizeof(union ubifs_dev_desc), GFP_NOFS);
+		if (!dev)
+			return -ENOMEM;
+		devlen = ubifs_encode_dev(dev, rdev);
+	}
+
+	req.new_ino_d = ALIGN(devlen, 8);
+	err = ubifs_budget_space(c, &req);
+	if (err) {
+		kfree(dev);
+		return err;
+	}
+
+	err = ubifs_prepare_create(dir, dentry, &nm);
+	if (err) {
+		kfree(dev);
+		goto out_budg;
+	}
+
+	sz_change = CALC_DENT_SIZE(fname_len(&nm));
+
+	inode = ubifs_new_inode(c, dir, mode, false);
+	if (IS_ERR(inode)) {
+		kfree(dev);
+		err = PTR_ERR(inode);
+		goto out_fname;
+	}
+
+	init_special_inode(inode, inode->i_mode, rdev);
+	inode->i_size = ubifs_inode(inode)->ui_size = devlen;
+	ui = ubifs_inode(inode);
+	ui->data = dev;
+	ui->data_len = devlen;
+
+	err = ubifs_init_security(dir, inode, &dentry->d_name);
+	if (err)
+		goto out_inode;
+
+	mutex_lock(&dir_ui->ui_mutex);
+	dir->i_size += sz_change;
+	dir_ui->ui_size = dir->i_size;
+	dir->i_mtime = inode_set_ctime_to_ts(dir, inode_get_ctime(inode));
+	err = ubifs_jnl_update(c, dir, &nm, inode, 0, 0);
+	if (err)
+		goto out_cancel;
+	mutex_unlock(&dir_ui->ui_mutex);
+
+	ubifs_release_budget(c, &req);
+	insert_inode_hash(inode);
+	d_instantiate(dentry, inode);
+	fscrypt_free_filename(&nm);
+	return 0;
+
+out_cancel:
+	dir->i_size -= sz_change;
+	dir_ui->ui_size = dir->i_size;
+	mutex_unlock(&dir_ui->ui_mutex);
+out_inode:
+	make_bad_inode(inode);
+	iput(inode);
+out_fname:
+	fscrypt_free_filename(&nm);
+out_budg:
+	ubifs_release_budget(c, &req);
+	return err;
+}
+
+static int ubifs_symlink(struct mnt_idmap *idmap, struct inode *dir,
+			 struct dentry *dentry, const char *symname)
+{
+	struct inode *inode;
+	struct ubifs_inode *ui;
+	struct ubifs_inode *dir_ui = ubifs_inode(dir);
+	struct ubifs_info *c = dir->i_sb->s_fs_info;
+	int err, sz_change, len = strlen(symname);
+	struct fscrypt_str disk_link;
+	struct ubifs_budget_req req = { .new_ino = 1, .new_dent = 1,
+					.dirtied_ino = 1 };
+	struct fscrypt_name nm;
+
+	dbg_gen("dent '%pd', target '%s' in dir ino %lu", dentry,
+		symname, dir->i_ino);
+
+	err = fscrypt_prepare_symlink(dir, symname, len, UBIFS_MAX_INO_DATA,
+				      &disk_link);
+	if (err)
+		return err;
+
+	/*
+	 * Budget request settings: new inode, new direntry and changing parent
+	 * directory inode.
+	 */
+	req.new_ino_d = ALIGN(disk_link.len - 1, 8);
+	err = ubifs_budget_space(c, &req);
+	if (err)
+		return err;
+
+	err = ubifs_prepare_create(dir, dentry, &nm);
+	if (err)
+		goto out_budg;
+
+	sz_change = CALC_DENT_SIZE(fname_len(&nm));
+
+	inode = ubifs_new_inode(c, dir, S_IFLNK | S_IRWXUGO, false);
+	if (IS_ERR(inode)) {
+		err = PTR_ERR(inode);
+		goto out_fname;
+	}
+
+	ui = ubifs_inode(inode);
+	ui->data = kmalloc(disk_link.len, GFP_NOFS);
+	if (!ui->data) {
+		err = -ENOMEM;
+		goto out_inode;
+	}
+
+	if (IS_ENCRYPTED(inode)) {
+		disk_link.name = ui->data; /* encrypt directly into ui->data */
+		err = fscrypt_encrypt_symlink(inode, symname, len, &disk_link);
+		if (err)
+			goto out_inode;
+	} else {
+		memcpy(ui->data, disk_link.name, disk_link.len);
+		inode->i_link = ui->data;
+	}
+
+	/*
+	 * The terminating zero byte is not written to the flash media and it
+	 * is put just to make later in-memory string processing simpler. Thus,
+	 * data length is @disk_link.len - 1, not @disk_link.len.
+	 */
+	ui->data_len = disk_link.len - 1;
+	inode->i_size = ubifs_inode(inode)->ui_size = disk_link.len - 1;
+
+	err = ubifs_init_security(dir, inode, &dentry->d_name);
+	if (err)
+		goto out_inode;
+
+	mutex_lock(&dir_ui->ui_mutex);
+	dir->i_size += sz_change;
+	dir_ui->ui_size = dir->i_size;
+	dir->i_mtime = inode_set_ctime_to_ts(dir, inode_get_ctime(inode));
+	err = ubifs_jnl_update(c, dir, &nm, inode, 0, 0);
+	if (err)
+		goto out_cancel;
+	mutex_unlock(&dir_ui->ui_mutex);
+
+	insert_inode_hash(inode);
+	d_instantiate(dentry, inode);
+	err = 0;
+	goto out_fname;
+
+out_cancel:
+	dir->i_size -= sz_change;
+	dir_ui->ui_size = dir->i_size;
+	mutex_unlock(&dir_ui->ui_mutex);
+out_inode:
+	/* Free inode->i_link before inode is marked as bad. */
+	fscrypt_free_inode(inode);
+	make_bad_inode(inode);
+	iput(inode);
+out_fname:
+	fscrypt_free_filename(&nm);
+out_budg:
+	ubifs_release_budget(c, &req);
+	return err;
+}
+
+/**
+ * lock_4_inodes - a wrapper for locking three UBIFS inodes.
+ * @inode1: first inode
+ * @inode2: second inode
+ * @inode3: third inode
+ * @inode4: fourth inode
+ *
+ * This function is used for 'ubifs_rename()' and @inode1 may be the same as
+ * @inode2 whereas @inode3 and @inode4 may be %NULL.
+ *
+ * We do not implement any tricks to guarantee strict lock ordering, because
+ * VFS has already done it for us on the @i_mutex. So this is just a simple
+ * wrapper function.
+ */
+static void lock_4_inodes(struct inode *inode1, struct inode *inode2,
+			  struct inode *inode3, struct inode *inode4)
+{
+	mutex_lock_nested(&ubifs_inode(inode1)->ui_mutex, WB_MUTEX_1);
+	if (inode2 != inode1)
+		mutex_lock_nested(&ubifs_inode(inode2)->ui_mutex, WB_MUTEX_2);
+	if (inode3)
+		mutex_lock_nested(&ubifs_inode(inode3)->ui_mutex, WB_MUTEX_3);
+	if (inode4)
+		mutex_lock_nested(&ubifs_inode(inode4)->ui_mutex, WB_MUTEX_4);
+}
+
+/**
+ * unlock_4_inodes - a wrapper for unlocking three UBIFS inodes for rename.
+ * @inode1: first inode
+ * @inode2: second inode
+ * @inode3: third inode
+ * @inode4: fourth inode
+ */
+static void unlock_4_inodes(struct inode *inode1, struct inode *inode2,
+			    struct inode *inode3, struct inode *inode4)
+{
+	if (inode4)
+		mutex_unlock(&ubifs_inode(inode4)->ui_mutex);
+	if (inode3)
+		mutex_unlock(&ubifs_inode(inode3)->ui_mutex);
+	if (inode1 != inode2)
+		mutex_unlock(&ubifs_inode(inode2)->ui_mutex);
+	mutex_unlock(&ubifs_inode(inode1)->ui_mutex);
+}
+
+static int do_rename(struct inode *old_dir, struct dentry *old_dentry,
+		     struct inode *new_dir, struct dentry *new_dentry,
+		     unsigned int flags)
+{
+	struct ubifs_info *c = old_dir->i_sb->s_fs_info;
+	struct inode *old_inode = d_inode(old_dentry);
+	struct inode *new_inode = d_inode(new_dentry);
+	struct inode *whiteout = NULL;
+	struct ubifs_inode *old_inode_ui = ubifs_inode(old_inode);
+	struct ubifs_inode *whiteout_ui = NULL;
+	int err, release, sync = 0, move = (new_dir != old_dir);
+	int is_dir = S_ISDIR(old_inode->i_mode);
+	int unlink = !!new_inode, new_sz, old_sz;
+	struct ubifs_budget_req req = { .new_dent = 1, .mod_dent = 1,
+					.dirtied_ino = 3 };
+	struct ubifs_budget_req ino_req = { .dirtied_ino = 1,
+			.dirtied_ino_d = ALIGN(old_inode_ui->data_len, 8) };
+	struct ubifs_budget_req wht_req;
+	unsigned int saved_nlink;
+	struct fscrypt_name old_nm, new_nm;
+
+	/*
+	 * Budget request settings:
+	 *   req: deletion direntry, new direntry, removing the old inode,
+	 *   and changing old and new parent directory inodes.
+	 *
+	 *   wht_req: new whiteout inode for RENAME_WHITEOUT.
+	 *
+	 *   ino_req: marks the target inode as dirty and does not write it.
+	 */
+
+	dbg_gen("dent '%pd' ino %lu in dir ino %lu to dent '%pd' in dir ino %lu flags 0x%x",
+		old_dentry, old_inode->i_ino, old_dir->i_ino,
+		new_dentry, new_dir->i_ino, flags);
+
+	if (unlink) {
+		ubifs_assert(c, inode_is_locked(new_inode));
+
+		/* Budget for old inode's data when its nlink > 1. */
+		req.dirtied_ino_d = ALIGN(ubifs_inode(new_inode)->data_len, 8);
+		err = ubifs_purge_xattrs(new_inode);
+		if (err)
+			return err;
+	}
+
+	if (unlink && is_dir) {
+		err = ubifs_check_dir_empty(new_inode);
+		if (err)
+			return err;
+	}
+
+	err = fscrypt_setup_filename(old_dir, &old_dentry->d_name, 0, &old_nm);
+	if (err)
+		return err;
+
+	err = fscrypt_setup_filename(new_dir, &new_dentry->d_name, 0, &new_nm);
+	if (err) {
+		fscrypt_free_filename(&old_nm);
+		return err;
+	}
+
+	new_sz = CALC_DENT_SIZE(fname_len(&new_nm));
+	old_sz = CALC_DENT_SIZE(fname_len(&old_nm));
+
+	err = ubifs_budget_space(c, &req);
+	if (err) {
+		fscrypt_free_filename(&old_nm);
+		fscrypt_free_filename(&new_nm);
+		return err;
+	}
+	err = ubifs_budget_space(c, &ino_req);
+	if (err) {
+		fscrypt_free_filename(&old_nm);
+		fscrypt_free_filename(&new_nm);
+		ubifs_release_budget(c, &req);
+		return err;
+	}
+
+	if (flags & RENAME_WHITEOUT) {
+		union ubifs_dev_desc *dev = NULL;
+
+		dev = kmalloc(sizeof(union ubifs_dev_desc), GFP_NOFS);
+		if (!dev) {
+			err = -ENOMEM;
+			goto out_release;
+		}
+
+		/*
+		 * The whiteout inode without dentry is pinned in memory,
+		 * umount won't happen during rename process because we
+		 * got parent dentry.
+		 */
+		whiteout = create_whiteout(old_dir, old_dentry);
+		if (IS_ERR(whiteout)) {
+			err = PTR_ERR(whiteout);
+			kfree(dev);
+			goto out_release;
+		}
+
+		whiteout_ui = ubifs_inode(whiteout);
+		whiteout_ui->data = dev;
+		whiteout_ui->data_len = ubifs_encode_dev(dev, MKDEV(0, 0));
+		ubifs_assert(c, !whiteout_ui->dirty);
+
+		memset(&wht_req, 0, sizeof(struct ubifs_budget_req));
+		wht_req.new_ino = 1;
+		wht_req.new_ino_d = ALIGN(whiteout_ui->data_len, 8);
+		/*
+		 * To avoid deadlock between space budget (holds ui_mutex and
+		 * waits wb work) and writeback work(waits ui_mutex), do space
+		 * budget before ubifs inodes locked.
+		 */
+		err = ubifs_budget_space(c, &wht_req);
+		if (err) {
+			/*
+			 * Whiteout inode can not be written on flash by
+			 * ubifs_jnl_write_inode(), because it's neither
+			 * dirty nor zero-nlink.
+			 */
+			iput(whiteout);
+			goto out_release;
+		}
+
+		/* Add the old_dentry size to the old_dir size. */
+		old_sz -= CALC_DENT_SIZE(fname_len(&old_nm));
+	}
+
+	lock_4_inodes(old_dir, new_dir, new_inode, whiteout);
+
+	/*
+	 * Like most other Unix systems, set the @i_ctime for inodes on a
+	 * rename.
+	 */
+	simple_rename_timestamp(old_dir, old_dentry, new_dir, new_dentry);
+
+	/* We must adjust parent link count when renaming directories */
+	if (is_dir) {
+		if (move) {
+			/*
+			 * @old_dir loses a link because we are moving
+			 * @old_inode to a different directory.
+			 */
+			drop_nlink(old_dir);
+			/*
+			 * @new_dir only gains a link if we are not also
+			 * overwriting an existing directory.
+			 */
+			if (!unlink)
+				inc_nlink(new_dir);
+		} else {
+			/*
+			 * @old_inode is not moving to a different directory,
+			 * but @old_dir still loses a link if we are
+			 * overwriting an existing directory.
+			 */
+			if (unlink)
+				drop_nlink(old_dir);
+		}
+	}
+
+	old_dir->i_size -= old_sz;
+	ubifs_inode(old_dir)->ui_size = old_dir->i_size;
+
+	/*
+	 * And finally, if we unlinked a direntry which happened to have the
+	 * same name as the moved direntry, we have to decrement @i_nlink of
+	 * the unlinked inode.
+	 */
+	if (unlink) {
+		/*
+		 * Directories cannot have hard-links, so if this is a
+		 * directory, just clear @i_nlink.
+		 */
+		saved_nlink = new_inode->i_nlink;
+		if (is_dir)
+			clear_nlink(new_inode);
+		else
+			drop_nlink(new_inode);
+	} else {
+		new_dir->i_size += new_sz;
+		ubifs_inode(new_dir)->ui_size = new_dir->i_size;
+	}
+
+	/*
+	 * Do not ask 'ubifs_jnl_rename()' to flush write-buffer if @old_inode
+	 * is dirty, because this will be done later on at the end of
+	 * 'ubifs_rename()'.
+	 */
+	if (IS_SYNC(old_inode)) {
+		sync = IS_DIRSYNC(old_dir) || IS_DIRSYNC(new_dir);
+		if (unlink && IS_SYNC(new_inode))
+			sync = 1;
+		/*
+		 * S_SYNC flag of whiteout inherits from the old_dir, and we
+		 * have already checked the old dir inode. So there is no need
+		 * to check whiteout.
+		 */
+	}
+
+	err = ubifs_jnl_rename(c, old_dir, old_inode, &old_nm, new_dir,
+			       new_inode, &new_nm, whiteout, sync);
+	if (err)
+		goto out_cancel;
+
+	unlock_4_inodes(old_dir, new_dir, new_inode, whiteout);
+	ubifs_release_budget(c, &req);
+
+	if (whiteout) {
+		ubifs_release_budget(c, &wht_req);
+		iput(whiteout);
+	}
+
+	mutex_lock(&old_inode_ui->ui_mutex);
+	release = old_inode_ui->dirty;
+	mark_inode_dirty_sync(old_inode);
+	mutex_unlock(&old_inode_ui->ui_mutex);
+
+	if (release)
+		ubifs_release_budget(c, &ino_req);
+	if (IS_SYNC(old_inode))
+		/*
+		 * Rename finished here. Although old inode cannot be updated
+		 * on flash, old ctime is not a big problem, don't return err
+		 * code to userspace.
+		 */
+		old_inode->i_sb->s_op->write_inode(old_inode, NULL);
+
+	fscrypt_free_filename(&old_nm);
+	fscrypt_free_filename(&new_nm);
+	return 0;
+
+out_cancel:
+	if (unlink) {
+		set_nlink(new_inode, saved_nlink);
+	} else {
+		new_dir->i_size -= new_sz;
+		ubifs_inode(new_dir)->ui_size = new_dir->i_size;
+	}
+	old_dir->i_size += old_sz;
+	ubifs_inode(old_dir)->ui_size = old_dir->i_size;
+	if (is_dir) {
+		if (move) {
+			inc_nlink(old_dir);
+			if (!unlink)
+				drop_nlink(new_dir);
+		} else {
+			if (unlink)
+				inc_nlink(old_dir);
+		}
+	}
+	unlock_4_inodes(old_dir, new_dir, new_inode, whiteout);
+	if (whiteout) {
+		ubifs_release_budget(c, &wht_req);
+		iput(whiteout);
+	}
+out_release:
+	ubifs_release_budget(c, &ino_req);
+	ubifs_release_budget(c, &req);
+	fscrypt_free_filename(&old_nm);
+	fscrypt_free_filename(&new_nm);
+	return err;
+}
+
+static int ubifs_xrename(struct inode *old_dir, struct dentry *old_dentry,
+			struct inode *new_dir, struct dentry *new_dentry)
+{
+	struct ubifs_info *c = old_dir->i_sb->s_fs_info;
+	struct ubifs_budget_req req = { .new_dent = 1, .mod_dent = 1,
+				.dirtied_ino = 2 };
+	int sync = IS_DIRSYNC(old_dir) || IS_DIRSYNC(new_dir);
+	struct inode *fst_inode = d_inode(old_dentry);
+	struct inode *snd_inode = d_inode(new_dentry);
+	int err;
+	struct fscrypt_name fst_nm, snd_nm;
+
+	ubifs_assert(c, fst_inode && snd_inode);
+
+	/*
+	 * Budget request settings: changing two direntries, changing the two
+	 * parent directory inodes.
+	 */
+
+	dbg_gen("dent '%pd' ino %lu in dir ino %lu exchange dent '%pd' ino %lu in dir ino %lu",
+		old_dentry, fst_inode->i_ino, old_dir->i_ino,
+		new_dentry, snd_inode->i_ino, new_dir->i_ino);
+
+	err = fscrypt_setup_filename(old_dir, &old_dentry->d_name, 0, &fst_nm);
+	if (err)
+		return err;
+
+	err = fscrypt_setup_filename(new_dir, &new_dentry->d_name, 0, &snd_nm);
+	if (err) {
+		fscrypt_free_filename(&fst_nm);
+		return err;
+	}
+
+	err = ubifs_budget_space(c, &req);
+	if (err)
+		goto out;
+
+	lock_4_inodes(old_dir, new_dir, NULL, NULL);
+
+	simple_rename_timestamp(old_dir, old_dentry, new_dir, new_dentry);
+
+	if (old_dir != new_dir) {
+		if (S_ISDIR(fst_inode->i_mode) && !S_ISDIR(snd_inode->i_mode)) {
+			inc_nlink(new_dir);
+			drop_nlink(old_dir);
+		}
+		else if (!S_ISDIR(fst_inode->i_mode) && S_ISDIR(snd_inode->i_mode)) {
+			drop_nlink(new_dir);
+			inc_nlink(old_dir);
+		}
+	}
+
+	err = ubifs_jnl_xrename(c, old_dir, fst_inode, &fst_nm, new_dir,
+				snd_inode, &snd_nm, sync);
+
+	unlock_4_inodes(old_dir, new_dir, NULL, NULL);
+	ubifs_release_budget(c, &req);
+
+out:
+	fscrypt_free_filename(&fst_nm);
+	fscrypt_free_filename(&snd_nm);
+	return err;
+}
+
+static int ubifs_rename(struct mnt_idmap *idmap,
+			struct inode *old_dir, struct dentry *old_dentry,
+			struct inode *new_dir, struct dentry *new_dentry,
+			unsigned int flags)
+{
+	int err;
+	struct ubifs_info *c = old_dir->i_sb->s_fs_info;
+
+	if (flags & ~(RENAME_NOREPLACE | RENAME_WHITEOUT | RENAME_EXCHANGE))
+		return -EINVAL;
+
+	ubifs_assert(c, inode_is_locked(old_dir));
+	ubifs_assert(c, inode_is_locked(new_dir));
+
+	err = fscrypt_prepare_rename(old_dir, old_dentry, new_dir, new_dentry,
+				     flags);
+	if (err)
+		return err;
+
+	if (flags & RENAME_EXCHANGE)
+		return ubifs_xrename(old_dir, old_dentry, new_dir, new_dentry);
+
+	return do_rename(old_dir, old_dentry, new_dir, new_dentry, flags);
+}
+
+int ubifs_getattr(struct mnt_idmap *idmap, const struct path *path,
+		  struct kstat *stat, u32 request_mask, unsigned int flags)
+{
+	loff_t size;
+	struct inode *inode = d_inode(path->dentry);
+	struct ubifs_inode *ui = ubifs_inode(inode);
+
+	mutex_lock(&ui->ui_mutex);
+
+	if (ui->flags & UBIFS_APPEND_FL)
+		stat->attributes |= STATX_ATTR_APPEND;
+	if (ui->flags & UBIFS_COMPR_FL)
+		stat->attributes |= STATX_ATTR_COMPRESSED;
+	if (ui->flags & UBIFS_CRYPT_FL)
+		stat->attributes |= STATX_ATTR_ENCRYPTED;
+	if (ui->flags & UBIFS_IMMUTABLE_FL)
+		stat->attributes |= STATX_ATTR_IMMUTABLE;
+
+	stat->attributes_mask |= (STATX_ATTR_APPEND |
+				STATX_ATTR_COMPRESSED |
+				STATX_ATTR_ENCRYPTED |
+				STATX_ATTR_IMMUTABLE);
+
+	generic_fillattr(&nop_mnt_idmap, request_mask, inode, stat);
+	stat->blksize = UBIFS_BLOCK_SIZE;
+	stat->size = ui->ui_size;
+
+	/*
+	 * Unfortunately, the 'stat()' system call was designed for block
+	 * device based file systems, and it is not appropriate for UBIFS,
+	 * because UBIFS does not have notion of "block". For example, it is
+	 * difficult to tell how many block a directory takes - it actually
+	 * takes less than 300 bytes, but we have to round it to block size,
+	 * which introduces large mistake. This makes utilities like 'du' to
+	 * report completely senseless numbers. This is the reason why UBIFS
+	 * goes the same way as JFFS2 - it reports zero blocks for everything
+	 * but regular files, which makes more sense than reporting completely
+	 * wrong sizes.
+	 */
+	if (S_ISREG(inode->i_mode)) {
+		size = ui->xattr_size;
+		size += stat->size;
+		size = ALIGN(size, UBIFS_BLOCK_SIZE);
+		/*
+		 * Note, user-space expects 512-byte blocks count irrespectively
+		 * of what was reported in @stat->size.
+		 */
+		stat->blocks = size >> 9;
+	} else
+		stat->blocks = 0;
+	mutex_unlock(&ui->ui_mutex);
+	return 0;
+}
+
+const struct inode_operations ubifs_dir_inode_operations = {
+	.lookup      = ubifs_lookup,
+	.create      = ubifs_create,
+	.link        = ubifs_link,
+	.symlink     = ubifs_symlink,
+	.unlink      = ubifs_unlink,
+	.mkdir       = ubifs_mkdir,
+	.rmdir       = ubifs_rmdir,
+	.mknod       = ubifs_mknod,
+	.rename      = ubifs_rename,
+	.setattr     = ubifs_setattr,
+	.getattr     = ubifs_getattr,
+	.listxattr   = ubifs_listxattr,
+	.update_time = ubifs_update_time,
+	.tmpfile     = ubifs_tmpfile,
+	.fileattr_get = ubifs_fileattr_get,
+	.fileattr_set = ubifs_fileattr_set,
+};
+
+const struct file_operations ubifs_dir_operations = {
+	.llseek         = generic_file_llseek,
+	.release        = ubifs_dir_release,
+	.read           = generic_read_dir,
+	.iterate_shared = ubifs_readdir,
+	.fsync          = ubifs_fsync,
+	.unlocked_ioctl = ubifs_ioctl,
+#ifdef CONFIG_COMPAT
+	.compat_ioctl   = ubifs_compat_ioctl,
+#endif
+};