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@xxxxxxxxxxxxxxx # 5.11+
> Reported-by: Dmitry Fomichev <Dmitry.Fomichev@xxxxxxx>
> Signed-off-by: Naohiro Aota <naohiro.aota@xxxxxxx>
> ---
> 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.
