[Qemu-devel] [PATCH 22/24] block/dirty-bitmap: add bdrv_remove_persistent_dirty_bitmap

[Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>]

Interface for removing persistent bitmap from its storage.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
---
 block/dirty-bitmap.c         | 19 +++++++++++++++++++
 include/block/block_int.h    |  3 +++
 include/block/dirty-bitmap.h |  3 +++
 3 files changed, 25 insertions(+)

diff --git a/block/dirty-bitmap.c b/block/dirty-bitmap.c
index 775181c9ab..7147a44bb7 100644
--- a/block/dirty-bitmap.c
+++ b/block/dirty-bitmap.c
@@ -328,12 +328,31 @@ void bdrv_release_dirty_bitmap(BlockDriverState *bs, BdrvDirtyBitmap *bitmap)
 /**
  * Release all named dirty bitmaps attached to a BDS (for use in bdrv_close()).
  * There must not be any frozen bitmaps attached.
+ * This function does not remove persistent bitmaps from the storage.
  */
 void bdrv_release_named_dirty_bitmaps(BlockDriverState *bs)
 {
     bdrv_do_release_matching_dirty_bitmap(bs, NULL, true);
 }
 
+/**
+ * Remove persistent dirty bitmap from the storage if it exists.
+ * Absence of bitmap is not an error, because we have the following scenario:
+ * BdrvDirtyBitmap can have .persistent = true but not yet saved and have no
+ * stored version. For such bitmap bdrv_remove_persistent_dirty_bitmap() should
+ * not fail.
+ * This function doesn't release corresponding BdrvDirtyBitmap.
+ */
+void bdrv_remove_persistent_dirty_bitmap(BlockDriverState *bs,
+                                         const char *name,
+                                         Error **errp)
+{
+    if (bs->drv && bs->drv->bdrv_remove_persistent_dirty_bitmap)
+    {
+        bs->drv->bdrv_remove_persistent_dirty_bitmap(bs, name, errp);
+    }
+}
+
 void bdrv_disable_dirty_bitmap(BdrvDirtyBitmap *bitmap)
 {
     assert(!bdrv_dirty_bitmap_frozen(bitmap));
diff --git a/include/block/block_int.h b/include/block/block_int.h
index a09c6e90c9..f6835cd6d2 100644
--- a/include/block/block_int.h
+++ b/include/block/block_int.h
@@ -326,6 +326,9 @@ struct BlockDriver {
                                                 Error **errp);
     bool (*bdrv_can_store_new_dirty_bitmap)(BlockDriverState *bs, const char *name,
                                             uint32_t granularity, Error **errp);
+    void (*bdrv_remove_persistent_dirty_bitmap)(BlockDriverState *bs,
+                                                const char *name,
+                                                Error **errp);
 
     QLIST_ENTRY(BlockDriver) list;
 };
diff --git a/include/block/dirty-bitmap.h b/include/block/dirty-bitmap.h
index b022b34964..ce126109e0 100644
--- a/include/block/dirty-bitmap.h
+++ b/include/block/dirty-bitmap.h
@@ -25,6 +25,9 @@ BdrvDirtyBitmap *bdrv_find_dirty_bitmap(BlockDriverState *bs,
 void bdrv_dirty_bitmap_make_anon(BdrvDirtyBitmap *bitmap);
 void bdrv_release_dirty_bitmap(BlockDriverState *bs, BdrvDirtyBitmap *bitmap);
 void bdrv_release_named_dirty_bitmaps(BlockDriverState *bs);
+void bdrv_remove_persistent_dirty_bitmap(BlockDriverState *bs,
+                                         const char *name,
+                                         Error **errp);
 void bdrv_disable_dirty_bitmap(BdrvDirtyBitmap *bitmap);
 void bdrv_enable_dirty_bitmap(BdrvDirtyBitmap *bitmap);
 BlockDirtyInfoList *bdrv_query_dirty_bitmaps(BlockDriverState *bs);
-- 
2.11.0