1 files changed, 57 insertions, 32 deletions

diff --git a/fs/fat/namei_vfat.c b/fs/fat/namei_vfat.c
index 88ccb2ee3537..9c04053a8f1c 100644
--- a/fs/fat/namei_vfat.c
+++ b/fs/fat/namei_vfat.c
@@ -889,16 +889,55 @@ out:
 	return err;
 }
 
+static int vfat_get_dotdot_de(struct inode *inode, struct buffer_head **bh,
+			      struct msdos_dir_entry **de)
+{
+	if (S_ISDIR(inode->i_mode)) {
+		if (fat_get_dotdot_entry(inode, bh, de))
+			return -EIO;
+	}
+	return 0;
+}
+
+static int vfat_sync_ipos(struct inode *dir, struct inode *inode)
+{
+	if (IS_DIRSYNC(dir))
+		return fat_sync_inode(inode);
+	mark_inode_dirty(inode);
+	return 0;
+}
+
+static int vfat_update_dotdot_de(struct inode *dir, struct inode *inode,
+				 struct buffer_head *dotdot_bh,
+				 struct msdos_dir_entry *dotdot_de)
+{
+	fat_set_start(dotdot_de, MSDOS_I(dir)->i_logstart);
+	mark_buffer_dirty_inode(dotdot_bh, inode);
+	if (IS_DIRSYNC(dir))
+		return sync_dirty_buffer(dotdot_bh);
+	return 0;
+}
+
+static void vfat_update_dir_metadata(struct inode *dir, struct timespec64 *ts)
+{
+	inode_inc_iversion(dir);
+	fat_truncate_time(dir, ts, S_CTIME | S_MTIME);
+	if (IS_DIRSYNC(dir))
+		(void)fat_sync_inode(dir);
+	else
+		mark_inode_dirty(dir);
+}
+
 static int vfat_rename(struct inode *old_dir, struct dentry *old_dentry,
 		       struct inode *new_dir, struct dentry *new_dentry)
 {
 	struct buffer_head *dotdot_bh;
-	struct msdos_dir_entry *dotdot_de;
+	struct msdos_dir_entry *dotdot_de = NULL;
 	struct inode *old_inode, *new_inode;
 	struct fat_slot_info old_sinfo, sinfo;
 	struct timespec64 ts;
 	loff_t new_i_pos;
-	int err, is_dir, update_dotdot, corrupt = 0;
+	int err, is_dir, corrupt = 0;
 	struct super_block *sb = old_dir->i_sb;
 
 	old_sinfo.bh = sinfo.bh = dotdot_bh = NULL;
@@ -909,15 +948,13 @@ static int vfat_rename(struct inode *old_dir, struct dentry *old_dentry,
 	if (err)
 		goto out;
 
-	is_dir = S_ISDIR(old_inode->i_mode);
-	update_dotdot = (is_dir && old_dir != new_dir);
-	if (update_dotdot) {
-		if (fat_get_dotdot_entry(old_inode, &dotdot_bh, &dotdot_de)) {
-			err = -EIO;
+	if (old_dir != new_dir) {
+		err = vfat_get_dotdot_de(old_inode, &dotdot_bh, &dotdot_de);
+		if (err)
 			goto out;
-		}
 	}
 
+	is_dir = S_ISDIR(old_inode->i_mode);
 	ts = current_time(old_dir);
 	if (new_inode) {
 		if (is_dir) {
@@ -938,21 +975,15 @@ static int vfat_rename(struct inode *old_dir, struct dentry *old_dentry,
 
 	fat_detach(old_inode);
 	fat_attach(old_inode, new_i_pos);
-	if (IS_DIRSYNC(new_dir)) {
-		err = fat_sync_inode(old_inode);
-		if (err)
-			goto error_inode;
-	} else
-		mark_inode_dirty(old_inode);
+	err = vfat_sync_ipos(new_dir, old_inode);
+	if (err)
+		goto error_inode;
 
-	if (update_dotdot) {
-		fat_set_start(dotdot_de, MSDOS_I(new_dir)->i_logstart);
-		mark_buffer_dirty_inode(dotdot_bh, old_inode);
-		if (IS_DIRSYNC(new_dir)) {
-			err = sync_dirty_buffer(dotdot_bh);
-			if (err)
-				goto error_dotdot;
-		}
+	if (dotdot_de) {
+		err = vfat_update_dotdot_de(new_dir, old_inode, dotdot_bh,
+					    dotdot_de);
+		if (err)
+			goto error_dotdot;
 		drop_nlink(old_dir);
 		if (!new_inode)
  			inc_nlink(new_dir);
@@ -962,12 +993,7 @@ static int vfat_rename(struct inode *old_dir, struct dentry *old_dentry,
 	old_sinfo.bh = NULL;
 	if (err)
 		goto error_dotdot;
-	inode_inc_iversion(old_dir);
-	fat_truncate_time(old_dir, &ts, S_CTIME|S_MTIME);
-	if (IS_DIRSYNC(old_dir))
-		(void)fat_sync_inode(old_dir);
-	else
-		mark_inode_dirty(old_dir);
+	vfat_update_dir_metadata(old_dir, &ts);
 
 	if (new_inode) {
 		drop_nlink(new_inode);
@@ -987,10 +1013,9 @@ error_dotdot:
 	/* data cluster is shared, serious corruption */
 	corrupt = 1;
 
-	if (update_dotdot) {
-		fat_set_start(dotdot_de, MSDOS_I(old_dir)->i_logstart);
-		mark_buffer_dirty_inode(dotdot_bh, old_inode);
-		corrupt |= sync_dirty_buffer(dotdot_bh);
+	if (dotdot_de) {
+		corrupt |= vfat_update_dotdot_de(old_dir, old_inode, dotdot_bh,
+						 dotdot_de);
 	}
 error_inode:
 	fat_detach(old_inode);