Re: [RFC v3 3/8] block: pass size to bdrv_unregister_buf()

[Hanna Reitz <hreitz@redhat.com>]

On 08.07.22 06:17, Stefan Hajnoczi wrote:
> The only implementor of bdrv_register_buf() is block/nvme.c, where the
> size is not needed when unregistering a buffer. This is because
> util/vfio-helpers.c can look up mappings by address.
>
> Future block drivers that implement bdrv_register_buf() may not be able
> to do their job given only the buffer address. Add a size argument to
> bdrv_unregister_buf().
>
> Also document the assumptions about
> bdrv_register_buf()/bdrv_unregister_buf() calls. The same <host, size>
> values that were given to bdrv_register_buf() must be given to
> bdrv_unregister_buf().
>
> gcc 11.2.1 emits a spurious warning that img_bench()'s buf_size local
> variable might be uninitialized, so it's necessary to silence the
> compiler.
>
> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
> ---
>   include/block/block-global-state.h          | 5 ++++-
>   include/block/block_int-common.h            | 2 +-
>   include/sysemu/block-backend-global-state.h | 2 +-
>   block/block-backend.c                       | 4 ++--
>   block/io.c                                  | 6 +++---
>   block/nvme.c                                | 2 +-
>   qemu-img.c                                  | 4 ++--
>   7 files changed, 14 insertions(+), 11 deletions(-)

Reviewed-by: Hanna Reitz <hreitz@redhat.com>