qcow2: Make size_to_clusters() return uint64_t

Sadly, some images may have more clusters than what can be represented
using a plain int. We should be prepared for that case (in
qcow2_check_refcounts() we actually were trying to catch that case, but
since size_to_clusters() truncated the returned value, that check never
did anything useful).

Cc: qemu-stable <qemu-stable@nongnu.org>
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

1 files changed, 3 insertions, 3 deletions

diff --git a/block/qcow2.h b/block/qcow2.h
index 61f1b57..d700bf1 100644
--- a/block/qcow2.h
+++ b/block/qcow2.h
@@ -415,7 +415,7 @@ static inline int64_t offset_into_cluster(BDRVQcow2State *s, int64_t offset)
     return offset & (s->cluster_size - 1);
 }
 
-static inline int size_to_clusters(BDRVQcow2State *s, int64_t size)
+static inline uint64_t size_to_clusters(BDRVQcow2State *s, uint64_t size)
 {
     return (size + (s->cluster_size - 1)) >> s->cluster_bits;
 }
@@ -509,8 +509,8 @@ int qcow2_update_cluster_refcount(BlockDriverState *bs, int64_t cluster_index,
                                   enum qcow2_discard_type type);
 
 int64_t qcow2_alloc_clusters(BlockDriverState *bs, uint64_t size);
-int qcow2_alloc_clusters_at(BlockDriverState *bs, uint64_t offset,
-    int nb_clusters);
+int64_t qcow2_alloc_clusters_at(BlockDriverState *bs, uint64_t offset,
+                                int64_t nb_clusters);
 int64_t qcow2_alloc_bytes(BlockDriverState *bs, int size);
 void qcow2_free_clusters(BlockDriverState *bs,
                           int64_t offset, int64_t size,