| Message ID | 574b670e016379e8b4230b52d9b46c1d97d9486b.1572125022.git.berto@igalia.com |
|---|---|
| State | New |
| Headers | show |
| Series | Add subcluster allocation to qcow2 | expand |
27.10.2019 0:25, Alberto Garcia wrote: > We are going to need it in other places. > > Signed-off-by: Alberto Garcia <berto@igalia.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> > --- > block/qcow2-cluster.c | 34 +++++++++++++++++++--------------- > 1 file changed, 19 insertions(+), 15 deletions(-) > > diff --git a/block/qcow2-cluster.c b/block/qcow2-cluster.c > index 6c1dcdc781..aa1010a515 100644 > --- a/block/qcow2-cluster.c > +++ b/block/qcow2-cluster.c > @@ -1068,6 +1068,24 @@ static void calculate_l2_meta(BlockDriverState *bs, uint64_t host_offset, > QLIST_INSERT_HEAD(&s->cluster_allocs, *m, next_in_flight); > } > > +/* Returns true if writing to a cluster requires COW */ > +static bool cluster_needs_cow(BlockDriverState *bs, uint64_t l2_entry) > +{ > + switch (qcow2_get_cluster_type(bs, l2_entry)) { > + case QCOW2_CLUSTER_NORMAL: > + if (l2_entry & QCOW_OFLAG_COPIED) { > + return false; > + } > + case QCOW2_CLUSTER_UNALLOCATED: > + case QCOW2_CLUSTER_COMPRESSED: > + case QCOW2_CLUSTER_ZERO_PLAIN: > + case QCOW2_CLUSTER_ZERO_ALLOC: > + return true; > + default: > + abort(); > + } > +} Not sure how much is it better than just return !(qcow2_get_cluster_type(bs, l2_entry) == QCOW2_CLUSTER_NORMAL && (l2_entry & QCOW_OFLAG_COPIED)); > + > /* > * Returns the number of contiguous clusters that can be used for an allocating > * write, but require COW to be performed (this includes yet unallocated space, > @@ -1080,25 +1098,11 @@ static int count_cow_clusters(BlockDriverState *bs, int nb_clusters, > > for (i = 0; i < nb_clusters; i++) { > uint64_t l2_entry = be64_to_cpu(l2_slice[l2_index + i]); > - QCow2ClusterType cluster_type = qcow2_get_cluster_type(bs, l2_entry); > - > - switch(cluster_type) { > - case QCOW2_CLUSTER_NORMAL: > - if (l2_entry & QCOW_OFLAG_COPIED) { > - goto out; > - } > + if (!cluster_needs_cow(bs, l2_entry)) { > break; > - case QCOW2_CLUSTER_UNALLOCATED: > - case QCOW2_CLUSTER_COMPRESSED: > - case QCOW2_CLUSTER_ZERO_PLAIN: > - case QCOW2_CLUSTER_ZERO_ALLOC: > - break; > - default: > - abort(); > } > } > > -out: > assert(i <= nb_clusters); > return i; > } >
diff --git a/block/qcow2-cluster.c b/block/qcow2-cluster.c index 6c1dcdc781..aa1010a515 100644 --- a/block/qcow2-cluster.c +++ b/block/qcow2-cluster.c @@ -1068,6 +1068,24 @@ static void calculate_l2_meta(BlockDriverState *bs, uint64_t host_offset, QLIST_INSERT_HEAD(&s->cluster_allocs, *m, next_in_flight); } +/* Returns true if writing to a cluster requires COW */ +static bool cluster_needs_cow(BlockDriverState *bs, uint64_t l2_entry) +{ + switch (qcow2_get_cluster_type(bs, l2_entry)) { + case QCOW2_CLUSTER_NORMAL: + if (l2_entry & QCOW_OFLAG_COPIED) { + return false; + } + case QCOW2_CLUSTER_UNALLOCATED: + case QCOW2_CLUSTER_COMPRESSED: + case QCOW2_CLUSTER_ZERO_PLAIN: + case QCOW2_CLUSTER_ZERO_ALLOC: + return true; + default: + abort(); + } +} + /* * Returns the number of contiguous clusters that can be used for an allocating * write, but require COW to be performed (this includes yet unallocated space, @@ -1080,25 +1098,11 @@ static int count_cow_clusters(BlockDriverState *bs, int nb_clusters, for (i = 0; i < nb_clusters; i++) { uint64_t l2_entry = be64_to_cpu(l2_slice[l2_index + i]); - QCow2ClusterType cluster_type = qcow2_get_cluster_type(bs, l2_entry); - - switch(cluster_type) { - case QCOW2_CLUSTER_NORMAL: - if (l2_entry & QCOW_OFLAG_COPIED) { - goto out; - } + if (!cluster_needs_cow(bs, l2_entry)) { break; - case QCOW2_CLUSTER_UNALLOCATED: - case QCOW2_CLUSTER_COMPRESSED: - case QCOW2_CLUSTER_ZERO_PLAIN: - case QCOW2_CLUSTER_ZERO_ALLOC: - break; - default: - abort(); } } -out: assert(i <= nb_clusters); return i; }
We are going to need it in other places. Signed-off-by: Alberto Garcia <berto@igalia.com> --- block/qcow2-cluster.c | 34 +++++++++++++++++++--------------- 1 file changed, 19 insertions(+), 15 deletions(-)