fs/ntfs3: Rework file operations

Rename now works "Add new name and remove old name".
"Remove old name and add new name" may result in bad inode
if we can't add new name and then can't restore (add) old name.

Signed-off-by: Konstantin Komarov <almaz.alexandrovich@paragon-software.com>

1 files changed, 63 insertions, 173 deletions

diff --git a/fs/ntfs3/namei.c b/fs/ntfs3/namei.c
index f79a399bd015..e58415d07132 100644
--- a/fs/ntfs3/namei.c
+++ b/fs/ntfs3/namei.c
@@ -152,12 +152,14 @@ static int ntfs_link(struct dentry *ode, struct inode *dir, struct dentry *de)
 	if (inode != dir)
 		ni_lock(ni);
 
-	dir->i_ctime = dir->i_mtime = inode->i_ctime = current_time(inode);
 	inc_nlink(inode);
 	ihold(inode);
 
 	err = ntfs_link_inode(inode, de);
+
 	if (!err) {
+		dir->i_ctime = dir->i_mtime = inode->i_ctime =
+			current_time(dir);
 		mark_inode_dirty(inode);
 		mark_inode_dirty(dir);
 		d_instantiate(de, inode);
@@ -249,25 +251,26 @@ static int ntfs_rmdir(struct inode *dir, struct dentry *dentry)
 /*
  * ntfs_rename - inode_operations::rename
  */
-static int ntfs_rename(struct user_namespace *mnt_userns, struct inode *old_dir,
-		       struct dentry *old_dentry, struct inode *new_dir,
+static int ntfs_rename(struct user_namespace *mnt_userns, struct inode *dir,
+		       struct dentry *dentry, struct inode *new_dir,
 		       struct dentry *new_dentry, u32 flags)
 {
 	int err;
-	struct super_block *sb = old_dir->i_sb;
+	struct super_block *sb = dir->i_sb;
 	struct ntfs_sb_info *sbi = sb->s_fs_info;
-	struct ntfs_inode *old_dir_ni = ntfs_i(old_dir);
+	struct ntfs_inode *dir_ni = ntfs_i(dir);
 	struct ntfs_inode *new_dir_ni = ntfs_i(new_dir);
-	struct ntfs_inode *old_ni;
-	struct ATTR_FILE_NAME *old_name, *new_name, *fname;
-	u8 name_type;
-	bool is_same;
-	struct inode *old_inode, *new_inode;
-	struct NTFS_DE *old_de, *new_de;
-	struct ATTRIB *attr;
-	struct ATTR_LIST_ENTRY *le;
-	u16 new_de_key_size;
-
+	struct inode *inode = d_inode(dentry);
+	struct ntfs_inode *ni = ntfs_i(inode);
+	struct inode *new_inode = d_inode(new_dentry);
+	struct NTFS_DE *de, *new_de;
+	bool is_same, is_bad;
+	/*
+	 * de		- memory of PATH_MAX bytes:
+	 * [0-1024)	- original name (dentry->d_name)
+	 * [1024-2048)	- paired to original name, usually DOS variant of dentry->d_name
+	 * [2048-3072)	- new name (new_dentry->d_name)
+	 */
 	static_assert(SIZEOF_ATTRIBUTE_FILENAME_MAX + SIZEOF_RESIDENT < 1024);
 	static_assert(SIZEOF_ATTRIBUTE_FILENAME_MAX + sizeof(struct NTFS_DE) <
 		      1024);
@@ -276,24 +279,18 @@ static int ntfs_rename(struct user_namespace *mnt_userns, struct inode *old_dir,
 	if (flags & ~RENAME_NOREPLACE)
 		return -EINVAL;
 
-	old_inode = d_inode(old_dentry);
-	new_inode = d_inode(new_dentry);
-
-	old_ni = ntfs_i(old_inode);
+	is_same = dentry->d_name.len == new_dentry->d_name.len &&
+		  !memcmp(dentry->d_name.name, new_dentry->d_name.name,
+			  dentry->d_name.len);
 
-	is_same = old_dentry->d_name.len == new_dentry->d_name.len &&
-		  !memcmp(old_dentry->d_name.name, new_dentry->d_name.name,
-			  old_dentry->d_name.len);
-
-	if (is_same && old_dir == new_dir) {
+	if (is_same && dir == new_dir) {
 		/* Nothing to do. */
-		err = 0;
-		goto out;
+		return 0;
 	}
 
-	if (ntfs_is_meta_file(sbi, old_inode->i_ino)) {
-		err = -EINVAL;
-		goto out;
+	if (ntfs_is_meta_file(sbi, inode->i_ino)) {
+		/* Should we print an error? */
+		return -EINVAL;
 	}
 
 	if (new_inode) {
@@ -304,168 +301,61 @@ static int ntfs_rename(struct user_namespace *mnt_userns, struct inode *old_dir,
 		ni_unlock(new_dir_ni);
 		dput(new_dentry);
 		if (err)
-			goto out;
+			return err;
 	}
 
 	/* Allocate PATH_MAX bytes. */
-	old_de = __getname();
-	if (!old_de) {
-		err = -ENOMEM;
-		goto out;
-	}
+	de = __getname();
+	if (!de)
+		return -ENOMEM;
 
-	err = fill_name_de(sbi, old_de, &old_dentry->d_name, NULL);
+	/* Translate dentry->d_name into unicode form. */
+	err = fill_name_de(sbi, de, &dentry->d_name, NULL);
 	if (err < 0)
-		goto out1;
-
-	old_name = (struct ATTR_FILE_NAME *)(old_de + 1);
+		goto out;
 
 	if (is_same) {
-		new_de = old_de;
+		/* Reuse 'de'. */
+		new_de = de;
 	} else {
-		new_de = Add2Ptr(old_de, 1024);
+		/* Translate new_dentry->d_name into unicode form. */
+		new_de = Add2Ptr(de, 2048);
 		err = fill_name_de(sbi, new_de, &new_dentry->d_name, NULL);
 		if (err < 0)
-			goto out1;
-	}
-
-	ni_lock_dir(old_dir_ni);
-	ni_lock(old_ni);
-
-	mi_get_ref(&old_dir_ni->mi, &old_name->home);
-
-	/* Get pointer to file_name in MFT. */
-	fname = ni_fname_name(old_ni, (struct cpu_str *)&old_name->name_len,
-			      &old_name->home, &le);
-	if (!fname) {
-		err = -EINVAL;
-		goto out2;
+			goto out;
 	}
 
-	/* Copy fname info from record into new fname. */
-	new_name = (struct ATTR_FILE_NAME *)(new_de + 1);
-	memcpy(&new_name->dup, &fname->dup, sizeof(fname->dup));
-
-	name_type = paired_name(fname->type);
-
-	/* Remove first name from directory. */
-	err = indx_delete_entry(&old_dir_ni->dir, old_dir_ni, old_de + 1,
-				le16_to_cpu(old_de->key_size), sbi);
-	if (err)
-		goto out3;
-
-	/* Remove first name from MFT. */
-	err = ni_remove_attr_le(old_ni, attr_from_name(fname), le);
-	if (err)
-		goto out4;
-
-	le16_add_cpu(&old_ni->mi.mrec->hard_links, -1);
-	old_ni->mi.dirty = true;
-
-	if (name_type != FILE_NAME_POSIX) {
-		/* Get paired name. */
-		fname = ni_fname_type(old_ni, name_type, &le);
-		if (fname) {
-			/* Remove second name from directory. */
-			err = indx_delete_entry(&old_dir_ni->dir, old_dir_ni,
-						fname, fname_full_size(fname),
-						sbi);
-			if (err)
-				goto out5;
-
-			/* Remove second name from MFT. */
-			err = ni_remove_attr_le(old_ni, attr_from_name(fname),
-						le);
-			if (err)
-				goto out6;
-
-			le16_add_cpu(&old_ni->mi.mrec->hard_links, -1);
-			old_ni->mi.dirty = true;
+	ni_lock_dir(dir_ni);
+	ni_lock(ni);
+
+	is_bad = false;
+	err = ni_rename(dir_ni, new_dir_ni, ni, de, new_de, &is_bad);
+	if (is_bad) {
+		/* Restore after failed rename failed too. */
+		make_bad_inode(inode);
+		ntfs_inode_err(inode, "failed to undo rename");
+		ntfs_set_state(sbi, NTFS_DIRTY_ERROR);
+	} else if (!err) {
+		inode->i_ctime = dir->i_ctime = dir->i_mtime =
+			current_time(dir);
+		mark_inode_dirty(inode);
+		mark_inode_dirty(dir);
+		if (dir != new_dir) {
+			new_dir->i_mtime = new_dir->i_ctime = dir->i_ctime;
+			mark_inode_dirty(new_dir);
 		}
-	}
-
-	/* Add new name. */
-	mi_get_ref(&old_ni->mi, &new_de->ref);
-	mi_get_ref(&ntfs_i(new_dir)->mi, &new_name->home);
-
-	new_de_key_size = le16_to_cpu(new_de->key_size);
-
-	/* Insert new name in MFT. */
-	err = ni_insert_resident(old_ni, new_de_key_size, ATTR_NAME, NULL, 0,
-				 &attr, NULL);
-	if (err)
-		goto out7;
-
-	attr->res.flags = RESIDENT_FLAG_INDEXED;
-
-	memcpy(Add2Ptr(attr, SIZEOF_RESIDENT), new_name, new_de_key_size);
-
-	le16_add_cpu(&old_ni->mi.mrec->hard_links, 1);
-	old_ni->mi.dirty = true;
-
-	/* Insert new name in directory. */
-	err = indx_insert_entry(&new_dir_ni->dir, new_dir_ni, new_de, sbi,
-				NULL);
-	if (err)
-		goto out8;
 
-	if (IS_DIRSYNC(new_dir))
-		err = ntfs_sync_inode(old_inode);
-	else
-		mark_inode_dirty(old_inode);
+		if (IS_DIRSYNC(dir))
+			ntfs_sync_inode(dir);
 
-	old_dir->i_ctime = old_dir->i_mtime = current_time(old_dir);
-	if (IS_DIRSYNC(old_dir))
-		(void)ntfs_sync_inode(old_dir);
-	else
-		mark_inode_dirty(old_dir);
-
-	if (old_dir != new_dir) {
-		new_dir->i_mtime = new_dir->i_ctime = old_dir->i_ctime;
-		mark_inode_dirty(new_dir);
-	}
-
-	if (old_inode) {
-		old_inode->i_ctime = old_dir->i_ctime;
-		mark_inode_dirty(old_inode);
+		if (IS_DIRSYNC(new_dir))
+			ntfs_sync_inode(inode);
 	}
 
-	err = 0;
-	/* Normal way* */
-	goto out2;
-
-out8:
-	/* undo
-	 * ni_insert_resident(old_ni, new_de_key_size, ATTR_NAME, NULL, 0,
-	 *			 &attr, NULL);
-	 */
-	mi_remove_attr(&old_ni->mi, attr);
-out7:
-	/* undo
-	 * ni_remove_attr_le(old_ni, attr_from_name(fname), le);
-	 */
-out6:
-	/* undo
-	 * indx_delete_entry(&old_dir_ni->dir, old_dir_ni,
-	 *					fname, fname_full_size(fname),
-	 *					sbi);
-	 */
-out5:
-	/* undo
-	 * ni_remove_attr_le(old_ni, attr_from_name(fname), le);
-	 */
-out4:
-	/* undo:
-	 * indx_delete_entry(&old_dir_ni->dir, old_dir_ni, old_de + 1,
-	 *			old_de->key_size, NULL);
-	 */
-out3:
-out2:
-	ni_unlock(old_ni);
-	ni_unlock(old_dir_ni);
-out1:
-	__putname(old_de);
+	ni_unlock(ni);
+	ni_unlock(dir_ni);
 out:
+	__putname(de);
 	return err;
 }