1 files changed, 29 insertions, 5 deletions
diff --git a/block/qcow2.h b/block/qcow2.h
index 5217bea8a2..a019831838 100644
--- a/block/qcow2.h
+++ b/block/qcow2.h
@@ -51,6 +51,9 @@
 
 #define L2_CACHE_SIZE 16
 
+/* Must be at least 4 to cover all cases of refcount table growth */
+#define REFCOUNT_CACHE_SIZE 4
+
 typedef struct QCowHeader {
     uint32_t magic;
     uint32_t version;
@@ -78,6 +81,9 @@ typedef struct QCowSnapshot {
     uint64_t vm_clock_nsec;
 } QCowSnapshot;
 
+struct Qcow2Cache;
+typedef struct Qcow2Cache Qcow2Cache;
+
 typedef struct BDRVQcowState {
     int cluster_bits;
     int cluster_size;
@@ -91,9 +97,10 @@ typedef struct BDRVQcowState {
     uint64_t cluster_offset_mask;
     uint64_t l1_table_offset;
     uint64_t *l1_table;
-    uint64_t *l2_cache;
-    uint64_t l2_cache_offsets[L2_CACHE_SIZE];
-    uint32_t l2_cache_counts[L2_CACHE_SIZE];
+
+    Qcow2Cache* l2_table_cache;
+    Qcow2Cache* refcount_block_cache;
+
     uint8_t *cluster_cache;
     uint8_t *cluster_data;
     uint64_t cluster_cache_offset;
@@ -102,8 +109,6 @@ typedef struct BDRVQcowState {
     uint64_t *refcount_table;
     uint64_t refcount_table_offset;
     uint32_t refcount_table_size;
-    uint64_t refcount_block_cache_offset;
-    uint16_t *refcount_block_cache;
     int64_t free_cluster_index;
     int64_t free_byte_offset;
 
@@ -204,6 +209,8 @@ uint64_t qcow2_alloc_compressed_cluster_offset(BlockDriverState *bs,
                                          int compressed_size);
 
 int qcow2_alloc_cluster_link_l2(BlockDriverState *bs, QCowL2Meta *m);
+int qcow2_discard_clusters(BlockDriverState *bs, uint64_t offset,
+    int nb_sectors);
 
 /* qcow2-snapshot.c functions */
 int qcow2_snapshot_create(BlockDriverState *bs, QEMUSnapshotInfo *sn_info);
@@ -215,4 +222,21 @@ int qcow2_snapshot_load_tmp(BlockDriverState *bs, const char *snapshot_name);
 void qcow2_free_snapshots(BlockDriverState *bs);
 int qcow2_read_snapshots(BlockDriverState *bs);
 
+/* qcow2-cache.c functions */
+Qcow2Cache *qcow2_cache_create(BlockDriverState *bs, int num_tables,
+    bool writethrough);
+int qcow2_cache_destroy(BlockDriverState* bs, Qcow2Cache *c);
+
+void qcow2_cache_entry_mark_dirty(Qcow2Cache *c, void *table);
+int qcow2_cache_flush(BlockDriverState *bs, Qcow2Cache *c);
+int qcow2_cache_set_dependency(BlockDriverState *bs, Qcow2Cache *c,
+    Qcow2Cache *dependency);
+void qcow2_cache_depends_on_flush(Qcow2Cache *c);
+
+int qcow2_cache_get(BlockDriverState *bs, Qcow2Cache *c, uint64_t offset,
+    void **table);
+int qcow2_cache_get_empty(BlockDriverState *bs, Qcow2Cache *c, uint64_t offset,
+    void **table);
+int qcow2_cache_put(BlockDriverState *bs, Qcow2Cache *c, void **table);
+
 #endif