Re: [Qemu-devel] [PATCH V9 10/11] quorum: Add quorum_co_flush().

[Max Reitz <mreitz@redhat.com>]

On 2013-10-02 14:39, Benoît Canet wrote:
> Makes a vote to select error if any.
Voting on the error code seems a little over the top to me. ;)

I mean, the idea's nice, but then you'd have to do the same for reads 
and writes, I think. Just doing this for flushes seems a little incoherent.

Max

> Signed-off-by: Benoit Canet <benoit@irqsave.net>
> ---
>   block/quorum.c | 34 ++++++++++++++++++++++++++++++++++
>   1 file changed, 34 insertions(+)
>
> diff --git a/block/quorum.c b/block/quorum.c
> index 084d030..0a28ab1 100644
> --- a/block/quorum.c
> +++ b/block/quorum.c
> @@ -641,12 +641,46 @@ free_exit:
>       return result;
>   }
>   
> +static coroutine_fn int quorum_co_flush(BlockDriverState *bs)
> +{
> +    BDRVQuorumState *s = bs->opaque;
> +    QuorumVoteVersion *winner = NULL;
> +    QuorumVotes error_votes;
> +    QuorumVoteValue result_value;
> +    int i;
> +    int result = 0;
> +    bool error = false;
> +
> +    QLIST_INIT(&error_votes.vote_list);
> +    error_votes.compare = quorum_64bits_compare;
> +
> +    for (i = 0; i < s->total; i++) {
> +        result = bdrv_co_flush(&s->bs[i]);
> +        if (result) {
> +            error = true;
> +            result_value.l = result;
> +            quorum_count_vote(&error_votes, &result_value, i);
> +        }
> +    }
> +
> +    if (error) {
> +        winner = quorum_get_vote_winner(&error_votes);
> +        result = winner->value.l;
> +    }
> +
> +    quorum_free_vote_list(&error_votes);
> +
> +    return result;
> +}
> +
>   static BlockDriver bdrv_quorum = {
>       .format_name        = "quorum",
>       .protocol_name      = "quorum",
>   
>       .instance_size      = sizeof(BDRVQuorumState),
>   
> +    .bdrv_co_flush_to_disk = quorum_co_flush,
> +
>       .bdrv_getlength     = quorum_getlength,
>   
>       .bdrv_aio_readv     = quorum_aio_readv,