From cd30d3bc78d9acbd505d0d6a4cff3b87e40a8187 Mon Sep 17 00:00:00 2001
From: Naohiro Aota <Naohiro.Aota@wdc.com>
Date: Wed, 21 Dec 2022 16:47:45 +0000
Subject: [PATCH] btrfs: zoned: fix uninitialized variable warning in
btrfs_get_dev_zones
Fix an uninitialized warning we get with -Wmaybe-uninitialized where it
thought zno may have been uninitialized, in both cases it depends on
zinfo->zone_cache but we know the value won't change between checks.
Reported-by: Josef Bacik <josef@toxicpanda.com>
Link: https://lore.kernel.org/linux-btrfs/af6c527cbd8bdc782e50bd33996ee83acc3a16fb.1671221596.git.josef@toxicpanda.com/
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
---
fs/btrfs/zoned.c | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)
diff --git a/fs/btrfs/zoned.c b/fs/btrfs/zoned.c
index 379d678e3894e..d46701a77b172 100644
--- a/fs/btrfs/zoned.c
+++ b/fs/btrfs/zoned.c
@@ -220,7 +220,6 @@ static int btrfs_get_dev_zones(struct btrfs_device *device, u64 pos,
struct blk_zone *zones, unsigned int *nr_zones)
{
struct btrfs_zoned_device_info *zinfo = device->zone_info;
- u32 zno;
int ret;
if (!*nr_zones)
@@ -235,6 +234,7 @@ static int btrfs_get_dev_zones(struct btrfs_device *device, u64 pos,
/* Check cache */
if (zinfo->zone_cache) {
unsigned int i;
+ u32 zno;
ASSERT(IS_ALIGNED(pos, zinfo->zone_size));
zno = pos >> zinfo->zone_size_shift;
@@ -274,9 +274,12 @@ static int btrfs_get_dev_zones(struct btrfs_device *device, u64 pos,
return -EIO;
/* Populate cache */
- if (zinfo->zone_cache)
+ if (zinfo->zone_cache) {
+ u32 zno = pos >> zinfo->zone_size_shift;
+
memcpy(zinfo->zone_cache + zno, zones,
sizeof(*zinfo->zone_cache) * *nr_zones);
+ }
return 0;
}