Re: [PATCH v3 05/14] nbd: Add types for extended headers

[Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>]

On 15.05.23 22:53, Eric Blake wrote:
> Add the constants and structs necessary for later patches to start
> implementing the NBD_OPT_EXTENDED_HEADERS extension in both the client
> and server, matching recent commit e6f3b94a934] in the upstream nbd
> project.  This patch does not change any existing behavior, but merely
> sets the stage.
> 
> This patch does not change the status quo that neither the client nor
> server use a packed-struct representation for the request header.
> 
> Signed-off-by: Eric Blake <eblake@redhat.com>


Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>

> ---
>   docs/interop/nbd.txt |  1 +
>   include/block/nbd.h  | 74 ++++++++++++++++++++++++++++++++------------
>   nbd/common.c         | 10 +++++-
>   3 files changed, 65 insertions(+), 20 deletions(-)
> 
> diff --git a/docs/interop/nbd.txt b/docs/interop/nbd.txt
> index f5ca25174a6..abaf4c28a96 100644
> --- a/docs/interop/nbd.txt
> +++ b/docs/interop/nbd.txt
> @@ -69,3 +69,4 @@ NBD_CMD_BLOCK_STATUS for "qemu:dirty-bitmap:", NBD_CMD_CACHE
>   NBD_CMD_FLAG_FAST_ZERO
>   * 5.2: NBD_CMD_BLOCK_STATUS for "qemu:allocation-depth"
>   * 7.1: NBD_FLAG_CAN_MULTI_CONN for shareable writable exports
> +* 8.1: NBD_OPT_EXTENDED_HEADERS
> diff --git a/include/block/nbd.h b/include/block/nbd.h
> index 50626ab2744..d753fb8006f 100644
> --- a/include/block/nbd.h
> +++ b/include/block/nbd.h
> @@ -87,13 +87,24 @@ typedef struct NBDStructuredReplyChunk {
>       uint32_t length; /* length of payload */
>   } QEMU_PACKED NBDStructuredReplyChunk;
> 

[..]

> -/* Extent chunk for NBD_REPLY_TYPE_BLOCK_STATUS */
> +/* Extent array for NBD_REPLY_TYPE_BLOCK_STATUS */

Why? NBDExtent is one extent, not extent array.

>   typedef struct NBDExtent {
>       uint32_t length;
>       uint32_t flags; /* NBD_STATE_* */
>   } QEMU_PACKED NBDExtent;
> 
> +/* Header of NBD_REPLY_TYPE_BLOCK_STATUS_EXT */



-- 
Best regards,
Vladimir