commit 4057a2b24a5f5dae826d438217f77332c3a6842e
author Max Reitz <mreitz@redhat.com> Mon Oct 27 11:12:53 2014 +0100
committer Stefan Hajnoczi <stefanha@redhat.com> Mon Nov 03 11:41:49 2014 +0000
tree 197972925d18f6827c9c9cb02579672fc7605619
parent b2f27e4438bb9eb302a0976e5b988bdfd55e65dc

block/qcow2: Implement status CB for amend

The only really time-consuming operation potentially performed by
qcow2_amend_options() is zero cluster expansion when downgrading qcow2
images from compat=1.1 to compat=0.10, so report status of that
operation and that operation only through the status CB.

For this, approximate the progress as the number of L1 entries visited
during the operation.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Benoît Canet <benoit.canet@nodalink.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Benoit Canet <benoit@irqsave.net>
Message-id: 1414404776-4919-5-git-send-email-mreitz@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

block/qcow2.c

diff --git a/block/qcow2.c b/block/qcow2.c
index 0242793..d120494 100644
--- a/block/qcow2.c
+++ b/block/qcow2.c
@@ -2550,7 +2550,8 @@
  * Downgrades an image's version. To achieve this, any incompatible features
  * have to be removed.
  */
-static int qcow2_downgrade(BlockDriverState *bs, int target_version)
+static int qcow2_downgrade(BlockDriverState *bs, int target_version,
+                           BlockDriverAmendStatusCB *status_cb)
 {
     BDRVQcowState *s = bs->opaque;
     int current_version = s->qcow_version;
@@ -2599,7 +2600,7 @@
     /* clearing autoclear features is trivial */
     s->autoclear_features = 0;
 
-    ret = qcow2_expand_zero_clusters(bs);
+    ret = qcow2_expand_zero_clusters(bs, status_cb);
     if (ret < 0) {
         return ret;
     }
@@ -2692,7 +2693,7 @@
                 return ret;
             }
         } else {
-            ret = qcow2_downgrade(bs, new_version);
+            ret = qcow2_downgrade(bs, new_version, status_cb);
             if (ret < 0) {
                 return ret;
             }