On Thu, May 16, 2019 at 10:47:57AM +0200, Johannes Thumshirn wrote:
> Currently btrfs is only supporting CRC32C as checksumming algorithm. As
> this is about to change provide a function to validate the checksum type in
> the superblock against all possible algorithms.
>
> This makes adding new algorithms easier as there are fewer places to adjust
> when adding new algorithms.
>
> Signed-off-by: Johannes Thumshirn <jthumshirn@xxxxxxx>
> Reviewed-by: Nikolay Borisov <nborisov@xxxxxxxx>
> ---
> fs/btrfs/disk-io.c | 24 +++++++++++++++++-------
> 1 file changed, 17 insertions(+), 7 deletions(-)
>
> diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
> index 663efce22d98..ab13282d91d2 100644
> --- a/fs/btrfs/disk-io.c
> +++ b/fs/btrfs/disk-io.c
> @@ -356,6 +356,16 @@ static int verify_parent_transid(struct extent_io_tree *io_tree,
> return ret;
> }
>
> +static bool btrfs_supported_super_csum(struct btrfs_super_block *sb)
> +{
> + switch (btrfs_super_csum_type(sb)) {
> + case BTRFS_CSUM_TYPE_CRC32:
> + return true;
> + default:
> + return false;
> + }
> +}
> +
> /*
> * Return 0 if the superblock checksum type matches the checksum value of that
> * algorithm. Pass the raw disk superblock data.
> @@ -368,6 +378,12 @@ static int btrfs_check_super_csum(struct btrfs_fs_info *fs_info,
> u16 csum_type = btrfs_super_csum_type(disk_sb);
> int ret = 0;
>
> + if (!btrfs_supported_super_csum(disk_sb)) {
> + btrfs_err(fs_info, "unsupported checksum algorithm %u",
> + csum_type);
> + ret = 1;
This can be direct 'return 1;', otherwise ok.
Reviewed-by: David Sterba <dsterba@xxxxxxxx>
