On Thu, May 27, 2021 at 10:46:59AM +0900, Naohiro Aota wrote:
In btrfs_get_dev_zone_info(), we have "u32 sb_zone" and calculate "sector_t sector" by shifting it. But, this "sector" is calculated in 32bit, leading it to be 0 for the 2nd superblock copy.
Since zone number is u32, shifting it to sector (sector_t) or physical address (u64) can easily trigger a missing cast bug like this.
This commit introduces helpers to convert zone number to sector/LBA, so we won't fall into the same pitfall again.
Fixes: 12659251ca5d ("btrfs: implement log-structured superblock for ZONED mode") Cc: stable@vger.kernel.org # 5.11+ Reported-by: Dmitry Fomichev Dmitry.Fomichev@wdc.com Signed-off-by: Naohiro Aota naohiro.aota@wdc.com
fs/btrfs/zoned.c | 23 ++++++++++++++++++----- 1 file changed, 18 insertions(+), 5 deletions(-)
diff --git a/fs/btrfs/zoned.c b/fs/btrfs/zoned.c index 5feb76bdfc06..a7f77f0a5a86 100644 --- a/fs/btrfs/zoned.c +++ b/fs/btrfs/zoned.c @@ -153,6 +153,19 @@ static inline u32 sb_zone_number(int shift, int mirror) return (u32)zone; } +static inline sector_t zone_start_sector(u32 zone_number, struct block_device *bdev) +{
- sector_t zone_sectors = bdev_zone_sectors(bdev);
- return (sector_t)zone_number << ilog2(zone_sectors);
+}
+static inline u64 zone_start_physical(u32 zone_number,
struct btrfs_zoned_device_info *zone_info)+{
- return (u64)zone_number << zone_info->zone_size_shift;
+}
I just noticed an indentation fix missed the patch. I will resend revised version.