[PATCH v9 5/6] blockdev: use state.bitmap in block-dirty-bitmap-add action

[Vladimir Sementsov-Ogievskiy]

Other bitmap related actions use the .bitmap pointer in .abort action,
let's do same here:

1. It helps further refactoring, as bitmap-add is the only bitmap
   action that uses state.action in .abort

2. It must be safe: transaction actions rely on the fact that on
   .abort() the state is the same as at the end of .prepare(), so that
   in .abort() we could precisely rollback the changes done by
   .prepare().
   The only way to remove the bitmap during transaction should be
   block-dirty-bitmap-remove action, but it postpones actual removal to
   .commit(), so we are OK on any rollback path. (Note also that
   bitmap-remove is the only bitmap action that has .commit() phase,
   except for simple g_free the state on .clean())

3. Again, other bitmap actions behave this way: keep the bitmap pointer
   during the transaction.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
---
 blockdev.c | 12 ++++--------
 1 file changed, 4 insertions(+), 8 deletions(-)

diff --git a/blockdev.c b/blockdev.c
index 6bcf80b18b..10003bdc52 100644
--- a/blockdev.c
+++ b/blockdev.c
@@ -1998,7 +1998,8 @@ static void block_dirty_bitmap_add_action(BlkActionState 
*common,
                                &local_err);
 
     if (!local_err) {
-        state->prepared = true;
+        state->bitmap = block_dirty_bitmap_lookup(action->node, action->name,
+                                                  NULL, &error_abort);
     } else {
         error_propagate(errp, local_err);
     }
@@ -2006,15 +2007,10 @@ static void 
block_dirty_bitmap_add_action(BlkActionState *common,
 
 static void block_dirty_bitmap_add_abort(void *opaque)
 {
-    BlockDirtyBitmapAdd *action;
     BlockDirtyBitmapState *state = opaque;
 
-    action = state->common.action->u.block_dirty_bitmap_add.data;
-    /* Should not be able to fail: IF the bitmap was added via .prepare(),
-     * then the node reference and bitmap name must have been valid.
-     */
-    if (state->prepared) {
-        qmp_block_dirty_bitmap_remove(action->node, action->name, 
&error_abort);
+    if (state->bitmap) {
+        bdrv_release_dirty_bitmap(state->bitmap);
     }
 }
 
-- 
2.34.1