[Qemu-devel] [RFC V3 04/24] qcow2: Make update_cluster_refcount public.

[Benoît Canet]

Also add a flush parameter to make flushing optional.

Signed-off-by: Benoit Canet <address@hidden>
---
 block/qcow2-refcount.c |   25 +++++++++++++++++--------
 block/qcow2.h          |    4 ++++
 2 files changed, 21 insertions(+), 8 deletions(-)

diff --git a/block/qcow2-refcount.c b/block/qcow2-refcount.c
index 5e3f915..faca64c 100644
--- a/block/qcow2-refcount.c
+++ b/block/qcow2-refcount.c
@@ -513,9 +513,10 @@ fail:
  * If the return value is non-negative, it is the new refcount of the cluster.
  * If it is negative, it is -errno and indicates an error.
  */
-static int update_cluster_refcount(BlockDriverState *bs,
-                                   int64_t cluster_index,
-                                   int addend)
+int update_cluster_refcount(BlockDriverState *bs,
+                            int64_t cluster_index,
+                            int addend,
+                            bool flush)
 {
     BDRVQcowState *s = bs->opaque;
     int ret;
@@ -525,7 +526,9 @@ static int update_cluster_refcount(BlockDriverState *bs,
         return ret;
     }
 
-    bdrv_flush(bs->file);
+    if (flush) {
+        bdrv_flush(bs->file);
+    }
 
     return get_refcount(bs, cluster_index);
 }
@@ -644,7 +647,7 @@ int64_t qcow2_alloc_bytes(BlockDriverState *bs, int size)
         if (free_in_cluster == 0)
             s->free_byte_offset = 0;
         if ((offset & (s->cluster_size - 1)) != 0)
-            update_cluster_refcount(bs, offset >> s->cluster_bits, 1);
+            update_cluster_refcount(bs, offset >> s->cluster_bits, 1, true);
     } else {
         offset = qcow2_alloc_clusters(bs, s->cluster_size);
         if (offset < 0) {
@@ -654,7 +657,7 @@ int64_t qcow2_alloc_bytes(BlockDriverState *bs, int size)
         if ((cluster_offset + s->cluster_size) == offset) {
             /* we are lucky: contiguous data */
             offset = s->free_byte_offset;
-            update_cluster_refcount(bs, offset >> s->cluster_bits, 1);
+            update_cluster_refcount(bs, offset >> s->cluster_bits, 1, true);
             s->free_byte_offset += size;
         } else {
             s->free_byte_offset = offset;
@@ -795,7 +798,10 @@ int qcow2_update_snapshot_refcount(BlockDriverState *bs,
                     } else {
                         uint64_t cluster_index = (offset & L2E_OFFSET_MASK) >> 
s->cluster_bits;
                         if (addend != 0) {
-                            refcount = update_cluster_refcount(bs, 
cluster_index, addend);
+                            refcount = update_cluster_refcount(bs,
+                                                               cluster_index,
+                                                               addend,
+                                                               true);
                         } else {
                             refcount = get_refcount(bs, cluster_index);
                         }
@@ -827,7 +833,10 @@ int qcow2_update_snapshot_refcount(BlockDriverState *bs,
 
 
             if (addend != 0) {
-                refcount = update_cluster_refcount(bs, l2_offset >> 
s->cluster_bits, addend);
+                refcount = update_cluster_refcount(bs,
+                                                   l2_offset >> 
s->cluster_bits,
+                                                   addend,
+                                                   true);
             } else {
                 refcount = get_refcount(bs, l2_offset >> s->cluster_bits);
             }
diff --git a/block/qcow2.h b/block/qcow2.h
index 858fef3..ee9aecc 100644
--- a/block/qcow2.h
+++ b/block/qcow2.h
@@ -304,6 +304,10 @@ void qcow2_free_clusters(BlockDriverState *bs,
     int64_t offset, int64_t size);
 void qcow2_free_any_clusters(BlockDriverState *bs,
     uint64_t cluster_offset, int nb_clusters);
+int update_cluster_refcount(BlockDriverState *bs,
+                            int64_t cluster_index,
+                            int addend,
+                            bool flush);
 
 int qcow2_update_snapshot_refcount(BlockDriverState *bs,
     int64_t l1_table_offset, int l1_size, int addend);
-- 
1.7.10.4