Am 25.05.2016 um 00:25 hat Eric Blake geschrieben:
> Rename to bdrv_pwrite_zeroes() to let the compiler ensure we
> cater to the updated semantics. Do the same for
> bdrv_aio_write_zeroes() and bdrv_co_write_zeroes(). For now,
> we still require sector alignment in the callers, via assertions.
>
> Signed-off-by: Eric Blake <ebl...@redhat.com>
> --- a/block/io.c
> +++ b/block/io.c
> @@ -603,18 +603,21 @@ int bdrv_write(BlockDriverState *bs, int64_t sector_num,
> return bdrv_rw_co(bs, sector_num, (uint8_t *)buf, nb_sectors, true, 0);
> }
>
> -int bdrv_write_zeroes(BlockDriverState *bs, int64_t sector_num,
> - int nb_sectors, BdrvRequestFlags flags)
> +int bdrv_pwrite_zeroes(BlockDriverState *bs, int64_t offset,
> + int count, BdrvRequestFlags flags)
> {
> - return bdrv_rw_co(bs, sector_num, NULL, nb_sectors, true,
> + assert(offset % BDRV_SECTOR_SIZE == 0);
> + assert(count % BDRV_SECTOR_SIZE == 0);
> + return bdrv_rw_co(bs, offset >> BDRV_SECTOR_BITS, NULL,
> + count >> BDRV_SECTOR_BITS, true,
> BDRV_REQ_ZERO_WRITE | flags);
> }
Should we go directly to bdrv_prwv_co() here so that we don't need to
assert BDRV_SECTOR_SIZE alignment in a byte-based function?
> -BlockAIOCB *bdrv_aio_write_zeroes(BlockDriverState *bs,
> - int64_t sector_num, int nb_sectors, BdrvRequestFlags flags,
> +BlockAIOCB *bdrv_aio_pwrite_zeroes(BlockDriverState *bs,
> + int64_t offset, int count, BdrvRequestFlags flags,
> BlockCompletionFunc *cb, void *opaque)
> {
> - trace_bdrv_aio_write_zeroes(bs, sector_num, nb_sectors, flags, opaque);
> + trace_bdrv_aio_pwrite_zeroes(bs, offset, count, flags, opaque);
> + assert(offset % BDRV_SECTOR_SIZE == 0);
> + assert(count % BDRV_SECTOR_SIZE == 0);
>
> - return bdrv_co_aio_rw_vector(bs, sector_num, NULL, nb_sectors,
> + return bdrv_co_aio_rw_vector(bs, offset >> BDRV_SECTOR_BITS, NULL,
> + count >> BDRV_SECTOR_BITS,
> BDRV_REQ_ZERO_WRITE | flags,
> cb, opaque, true);
> }
Here the same would be nice, but we don't have a byte-based AIO
interface yet, so I'd agree with leaving the assertion here.
Kevin
