Am 03.02.2014 um 22:51 hat Benoît Canet geschrieben:
> From: Benoît Canet <ben...@irqsave.net>
>
> Signed-off-by: Benoit Canet <ben...@irqsave.net>
> Reviewed-by: Max Reitz <mre...@redhat.com>
> ---
> block/quorum.c | 51 +++++++++++++++++++++++++++++++++++++++++++++++++++
> 1 file changed, 51 insertions(+)
>
> diff --git a/block/quorum.c b/block/quorum.c
> index cef4424..677a96d 100644
> --- a/block/quorum.c
> +++ b/block/quorum.c
> @@ -619,6 +619,56 @@ static void quorum_invalidate_cache(BlockDriverState *bs)
> }
> }
>
> +static int64_t coroutine_fn quorum_co_get_block_status(BlockDriverState *bs,
> + int64_t sector_num,
> + int nb_sectors,
> + int *pnum)
> +{
> + BDRVQuorumState *s = bs->opaque;
> + QuorumVoteVersion *winner = NULL;
> + QuorumVotes result_votes, num_votes;
> + QuorumVoteValue result_value, num_value;
> + int i, num;
> + int64_t result = 0;
> +
> + QLIST_INIT(&result_votes.vote_list);
> + QLIST_INIT(&num_votes.vote_list);
> + result_votes.compare = quorum_64bits_compare;
> + num_votes.compare = quorum_64bits_compare;
> +
> + for (i = 0; i < s->total; i++) {
> + result = bdrv_get_block_status(s->bs[i], sector_num, nb_sectors,
> &num);
> + /* skip failed requests */
> + if (result < 0) {
> + continue;
> + }
> + result_value.l = result & BDRV_BLOCK_DATA;
> + num_value.l = num;
> + quorum_count_vote(&result_votes, &result_value, i);
> + quorum_count_vote(&num_votes, &num_value, i);
> + }
This doesn't work. bdrv_get_block_status() doesn't guarantee that it
returns all consecutive blocks with the same status. You need to call it
in a loop here, or change bdrv_get_block_status() so that it loops
itself.
> + winner = quorum_get_vote_winner(&result_votes);
> + if (winner->vote_count < s->threshold) {
> + result = -EIO;
> + goto free_exit;
> + }
> + result = winner->value.l;
> +
> + winner = quorum_get_vote_winner(&num_votes);
> + if (winner->vote_count < s->threshold) {
> + result = -EIO;
> + goto free_exit;
> + }
> + *pnum = winner->value.l;
You can take the status from one group of devices and the number of
blocks that share this state from another group?!
> +
> +free_exit:
> + quorum_free_vote_list(&result_votes);
> + quorum_free_vote_list(&num_votes);
> +
> + return result;
> +}
> +
> static BlockDriver bdrv_quorum = {
> .format_name = "quorum",
> .protocol_name = "quorum",
> @@ -630,6 +680,7 @@ static BlockDriver bdrv_quorum = {
> .bdrv_aio_readv = quorum_aio_readv,
> .bdrv_aio_writev = quorum_aio_writev,
> .bdrv_invalidate_cache = quorum_invalidate_cache,
> + .bdrv_co_get_block_status = quorum_co_get_block_status,
> };
>
> static void bdrv_quorum_init(void)
Kevin
