+typedef enum QCow2MetadataOverlap {
+ QCOW2_OL_MAIN_HEADER_BITNR = 0,
+ QCOW2_OL_ACTIVE_L1_BITNR = 1,
+ QCOW2_OL_ACTIVE_L2_BITNR = 2,
+ QCOW2_OL_REFCOUNT_TABLE_BITNR = 3,
+ QCOW2_OL_REFCOUNT_BLOCK_BITNR = 4,
+ QCOW2_OL_SNAPSHOT_TABLE_BITNR = 5,
+ QCOW2_OL_INACTIVE_L1_BITNR = 6,
+ QCOW2_OL_INACTIVE_L2_BITNR = 7,
+
+ QCOW2_OL_MAX_BITNR = 8,
+
+ QCOW2_OL_NONE = 0,
+ QCOW2_OL_MAIN_HEADER = (1 << QCOW2_OL_MAIN_HEADER_BITNR),
+ QCOW2_OL_ACTIVE_L1 = (1 << QCOW2_OL_ACTIVE_L1_BITNR),
+ QCOW2_OL_ACTIVE_L2 = (1 << QCOW2_OL_ACTIVE_L2_BITNR),
+ QCOW2_OL_REFCOUNT_TABLE = (1 << QCOW2_OL_REFCOUNT_TABLE_BITNR),
+ QCOW2_OL_REFCOUNT_BLOCK = (1 << QCOW2_OL_REFCOUNT_BLOCK_BITNR),
+ QCOW2_OL_SNAPSHOT_TABLE = (1 << QCOW2_OL_SNAPSHOT_TABLE_BITNR),
+ QCOW2_OL_INACTIVE_L1 = (1 << QCOW2_OL_INACTIVE_L1_BITNR),
+ /* NOTE: Checking overlaps with inactive L2 tables will result in bdrv
+ * reads. */
+ QCOW2_OL_INACTIVE_L2 = (1 << QCOW2_OL_INACTIVE_L2_BITNR),
+} QCow2MetadataOverlap;
+
+/* Perform all overlap checks which can be done in constant time */
+#define QCOW2_OL_CONSTANT \
+ (QCOW2_OL_MAIN_HEADER | QCOW2_OL_ACTIVE_L1 | QCOW2_OL_REFCOUNT_TABLE | \
+ QCOW2_OL_SNAPSHOT_TABLE)
+
+/* Perform all overlap checks which don't require disk access */
+#define QCOW2_OL_CACHED \
+ (QCOW2_OL_CONSTANT | QCOW2_OL_ACTIVE_L2 | QCOW2_OL_REFCOUNT_BLOCK | \
+ QCOW2_OL_INACTIVE_L1)
+
+/* Perform all overlap checks */
+#define QCOW2_OL_ALL \
+ (QCOW2_OL_CACHED | QCOW2_OL_INACTIVE_L2)
+