Message ID | 1391464280-25627-10-git-send-email-benoit.canet@irqsave.net |
---|---|
State | New |
Headers | show |
Am 03.02.2014 um 22:51 hat Benoît Canet geschrieben: > From: Benoît Canet <benoit@irqsave.net> > > Signed-off-by: Benoit Canet <benoit@irqsave.net> > Reviewed-by: Max Reitz <mreitz@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
Le Tuesday 04 Feb 2014 à 16:49:22 (+0100), Kevin Wolf a écrit : > Am 03.02.2014 um 22:51 hat Benoît Canet geschrieben: > > From: Benoît Canet <benoit@irqsave.net> > > > > Signed-off-by: Benoit Canet <benoit@irqsave.net> > > Reviewed-by: Max Reitz <mreitz@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. I don't see what can be done with the results generated by the loop. Does quorum really need this function ? Best regards Benoît > > > + 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
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); + } + + 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; + +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)