Re: [PATCH v6 04/13] block: pass size to bdrv_unregister_buf()

[Stefano Garzarella <sgarzare@redhat.com>]

On Thu, Oct 06, 2022 at 05:34:58PM -0400, 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: Stefano Garzarella <sgarzare@redhat.com>