Re: [Qemu-devel] [PATCH v8 20/21] vvfat: Switch to .bdrv_co_block_status()

[Kevin Wolf]

Am 13.02.2018 um 21:27 hat Eric Blake geschrieben:
> We are gradually moving away from sector-based interfaces, towards
> byte-based.  Update the vvfat driver accordingly.  Note that we
> can rely on the block driver having already clamped limits to our
> block size, and simplify accordingly.
> 
> Signed-off-by: Eric Blake <address@hidden>
> Reviewed-by: Vladimir Sementsov-Ogievskiy <address@hidden>
> Reviewed-by: Fam Zheng <address@hidden>
> 
> ---
> v5-v7: no change
> v4: rebase to interface tweak
> v3: no change
> v2: rebase to earlier changes, simplify
> ---
>  block/vvfat.c | 16 +++++++---------
>  1 file changed, 7 insertions(+), 9 deletions(-)
> 
> diff --git a/block/vvfat.c b/block/vvfat.c
> index 7e06ebacf61..4a17a49e128 100644
> --- a/block/vvfat.c
> +++ b/block/vvfat.c
> @@ -3088,15 +3088,13 @@ vvfat_co_pwritev(BlockDriverState *bs, uint64_t 
> offset, uint64_t bytes,
>      return ret;
>  }
> 
> -static int64_t coroutine_fn vvfat_co_get_block_status(BlockDriverState *bs,
> -        int64_t sector_num, int nb_sectors, int *n, BlockDriverState **file)
> +static int coroutine_fn vvfat_co_block_status(BlockDriverState *bs,
> +                                              bool want_zero, int64_t offset,
> +                                              int64_t bytes, int64_t *n,
> +                                              int64_t *map,
> +                                              BlockDriverState **file)
>  {
> -    *n = bs->total_sectors - sector_num;
> -    if (*n > nb_sectors) {
> -        *n = nb_sectors;
> -    } else if (*n < 0) {
> -        return 0;
> -    }
> +    *n = bytes;
>      return BDRV_BLOCK_DATA;
>  }

Preexisting, but this is inconsistent with other protocol drivers as far
as OFFSET_VALID is concerned (as I hinted in another mail, I like it
better this way, but it's still inconsistent).

Do we actually need any callback here or could the solution be to simply
remove it like with nvme?

Kevin