On 5/6/20 4:25 AM, Vladimir Sementsov-Ogievskiy wrote:
> raw_co_block_status() in block/file-posix.c never returns 0, so
> unallocated_blocks_are_zero is useless. Drop it.
As in 4/8, you are correct that it had no impact on block_status, but it
did affect qemu-img convert. So again, removing the clients first makes
this easier to justify as a cleanup patch.
That said...
>
> Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
> ---
> block/file-posix.c | 3 ---
> 1 file changed, 3 deletions(-)
>
> diff --git a/block/file-posix.c b/block/file-posix.c
> index 05e094be29..5c01735108 100644
> --- a/block/file-posix.c
> +++ b/block/file-posix.c
> @@ -2878,9 +2878,6 @@ static int coroutine_fn raw_co_pwrite_zeroes(
>
> static int raw_get_info(BlockDriverState *bs, BlockDriverInfo *bdi)
> {
> - BDRVRawState *s = bs->opaque;
> -
> - bdi->unallocated_blocks_are_zero = s->discard_zeroes;
> return 0;
> }
the function now does nothing. Hmm - why does bdrv_get_info() return
-ENOTSUP if the driver does not implement this function? Wouldn't it be
better if the block layer could allow us to omit .bdrv_get_info and do
the same thing, without us having to write a dummy function that does
nothing but return 0? As separate patches, of course, as it would
require changing several existing bdrv_get_info() callers to behave
sanely when getting an all-0 success return where they now deal with an
-ENOTSUP return.
So in the meantime, yes, we need this placeholder.
Reviewed-by: Eric Blake <eblake@redhat.com>
--
Eric Blake, Principal Software Engineer
Red Hat, Inc. +1-919-301-3226
Virtualization: qemu.org | libvirt.org