1 files changed, 12 insertions, 15 deletions

diff --git a/fs/exfat/dir.c b/fs/exfat/dir.c
index bc48f3329921..598081d0d059 100644
--- a/fs/exfat/dir.c
+++ b/fs/exfat/dir.c
@@ -218,7 +218,10 @@ static void exfat_free_namebuf(struct exfat_dentry_namebuf *nb)
 	exfat_init_namebuf(nb);
 }
 
-/* skip iterating emit_dots when dir is empty */
+/*
+ * Before calling dir_emit*(), sbi->s_lock should be released
+ * because page fault can occur in dir_emit*().
+ */
 #define ITER_POS_FILLED_DOTS    (2)
 static int exfat_iterate(struct file *file, struct dir_context *ctx)
 {
@@ -233,11 +236,10 @@ static int exfat_iterate(struct file *file, struct dir_context *ctx)
 	int err = 0, fake_offset = 0;
 
 	exfat_init_namebuf(nb);
-	mutex_lock(&EXFAT_SB(sb)->s_lock);
 
 	cpos = ctx->pos;
 	if (!dir_emit_dots(file, ctx))
-		goto unlock;
+		goto out;
 
 	if (ctx->pos == ITER_POS_FILLED_DOTS) {
 		cpos = 0;
@@ -249,16 +251,18 @@ static int exfat_iterate(struct file *file, struct dir_context *ctx)
 	/* name buffer should be allocated before use */
 	err = exfat_alloc_namebuf(nb);
 	if (err)
-		goto unlock;
+		goto out;
 get_new:
+	mutex_lock(&EXFAT_SB(sb)->s_lock);
+
 	if (ei->flags == ALLOC_NO_FAT_CHAIN && cpos >= i_size_read(inode))
 		goto end_of_dir;
 
 	err = exfat_readdir(inode, &cpos, &de);
 	if (err) {
 		/*
-		 * At least we tried to read a sector.  Move cpos to next sector
-		 * position (should be aligned).
+		 * At least we tried to read a sector.
+		 * Move cpos to next sector position (should be aligned).
 		 */
 		if (err == -EIO) {
 			cpos += 1 << (sb->s_blocksize_bits);
@@ -281,16 +285,10 @@ get_new:
 		inum = iunique(sb, EXFAT_ROOT_INO);
 	}
 
-	/*
-	 * Before calling dir_emit(), sb_lock should be released.
-	 * Because page fault can occur in dir_emit() when the size
-	 * of buffer given from user is larger than one page size.
-	 */
 	mutex_unlock(&EXFAT_SB(sb)->s_lock);
 	if (!dir_emit(ctx, nb->lfn, strlen(nb->lfn), inum,
 			(de.attr & ATTR_SUBDIR) ? DT_DIR : DT_REG))
-		goto out_unlocked;
-	mutex_lock(&EXFAT_SB(sb)->s_lock);
+		goto out;
 	ctx->pos = cpos;
 	goto get_new;
 
@@ -298,9 +296,8 @@ end_of_dir:
 	if (!cpos && fake_offset)
 		cpos = ITER_POS_FILLED_DOTS;
 	ctx->pos = cpos;
-unlock:
 	mutex_unlock(&EXFAT_SB(sb)->s_lock);
-out_unlocked:
+out:
 	/*
 	 * To improve performance, free namebuf after unlock sb_lock.
 	 * If namebuf is not allocated, this function do nothing