aboutsummaryrefslogtreecommitdiff
path: root/block/qcow2.c
diff options
context:
space:
mode:
authorAlberto Garcia <berto@igalia.com>2020-07-10 18:12:51 +0200
committerMax Reitz <mreitz@redhat.com>2020-08-25 08:33:20 +0200
commitd0346b5591825bab4d4b35aefb0ab0d7650e3641 (patch)
treed4c0f80f2702fdc2544526fcb3b9474eb338a525 /block/qcow2.c
parenta3c7d9162513c2bea742f4278a58e401c6f37d0c (diff)
downloadqemu-d0346b5591825bab4d4b35aefb0ab0d7650e3641.zip
qemu-d0346b5591825bab4d4b35aefb0ab0d7650e3641.tar.gz
qemu-d0346b5591825bab4d4b35aefb0ab0d7650e3641.tar.bz2
qcow2: Add subcluster-related fields to BDRVQcow2State
This patch adds the following new fields to BDRVQcow2State: - subclusters_per_cluster: Number of subclusters in a cluster - subcluster_size: The size of each subcluster, in bytes - subcluster_bits: No. of bits so 1 << subcluster_bits = subcluster_size Images without subclusters are treated as if they had exactly one subcluster per cluster (i.e. subcluster_size = cluster_size). Signed-off-by: Alberto Garcia <berto@igalia.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Message-Id: <55bfeac86b092fa2c9d182a95cbeb479ff7eca4f.1594396418.git.berto@igalia.com> Signed-off-by: Max Reitz <mreitz@redhat.com>
Diffstat (limited to 'block/qcow2.c')
-rw-r--r--block/qcow2.c5
1 files changed, 5 insertions, 0 deletions
diff --git a/block/qcow2.c b/block/qcow2.c
index 6738daa..fb4584d 100644
--- a/block/qcow2.c
+++ b/block/qcow2.c
@@ -1444,6 +1444,11 @@ static int coroutine_fn qcow2_do_open(BlockDriverState *bs, QDict *options,
}
}
+ s->subclusters_per_cluster =
+ has_subclusters(s) ? QCOW_EXTL2_SUBCLUSTERS_PER_CLUSTER : 1;
+ s->subcluster_size = s->cluster_size / s->subclusters_per_cluster;
+ s->subcluster_bits = ctz32(s->subcluster_size);
+
/* Check support for various header values */
if (header.refcount_order > 6) {
error_setg(errp, "Reference count entry width too large; may not "