From 55c9fca5f56d3d3242b4c1035479d8311f3b2e2a Mon Sep 17 00:00:00 2001
From: Sidong Yang <realwakka@gmail.com>
Date: Thu, 26 Aug 2021 14:44:36 +0000
Subject: [PATCH] btrfs: reflink: initialize return value to 0 in btrfs_extent_same()
Git-commit: 44bee215f72f13874c0e734a0712c2e3264c0108
Patch-mainline: v5.16-rc1
References: stable-5.14.19

[ Upstream commit 44bee215f72f13874c0e734a0712c2e3264c0108 ]

Fix a warning reported by smatch that ret could be returned without
initialized.  The dedupe operations are supposed to to return 0 for a 0
length range but the caller does not pass olen == 0. To keep this
behaviour and also fix the warning initialize ret to 0.

Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Sidong Yang <realwakka@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 fs/btrfs/reflink.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/btrfs/reflink.c b/fs/btrfs/reflink.c
index 9b0814318e72..c71e49782e86 100644
--- a/fs/btrfs/reflink.c
+++ b/fs/btrfs/reflink.c
@@ -649,7 +649,7 @@ static int btrfs_extent_same_range(struct inode *src, u64 loff, u64 len,
 static int btrfs_extent_same(struct inode *src, u64 loff, u64 olen,
 			     struct inode *dst, u64 dst_loff)
 {
-	int ret;
+	int ret = 0;
 	u64 i, tail_len, chunk_count;
 	struct btrfs_root *root_dst = BTRFS_I(dst)->root;
 
-- 
2.26.2