[pve-devel] [PATCH qemu v5 05/32] PVE backup: backup-access api: indicate situation where a bitmap was recreated

[Fiona Ebner]

The backup-access api keeps track of what bitmap names got used for
which devices and thus knows when a bitmap went missing. Propagate
this information to the QMP user with a new 'missing-recreated'
variant for the taken bitmap action.

Signed-off-by: Fiona Ebner <f.ebner at proxmox.com>
---

New in v5.

 pve-backup.c         | 6 +++++-
 qapi/block-core.json | 9 ++++++++-
 2 files changed, 13 insertions(+), 2 deletions(-)

diff --git a/pve-backup.c b/pve-backup.c
index bcbb9eeb5b..d616449e5d 100644
--- a/pve-backup.c
+++ b/pve-backup.c
@@ -1036,7 +1036,11 @@ BackupAccessInfoList *coroutine_fn qmp_backup_access_setup(
                     goto err;
                 }
                 bdrv_set_dirty_bitmap(bitmap, 0, di->size);
-                action = PBS_BITMAP_ACTION_NEW;
+                if (same_bitmap_name) {
+                    action = PBS_BITMAP_ACTION_MISSING_RECREATED;
+                } else {
+                    action = PBS_BITMAP_ACTION_NEW;
+                }
             } else {
                 /* track clean chunks as reused */
                 dirty = MIN(bdrv_get_dirty_count(bitmap), di->size);
diff --git a/qapi/block-core.json b/qapi/block-core.json
index 63a5be0f3f..fa6166ab79 100644
--- a/qapi/block-core.json
+++ b/qapi/block-core.json
@@ -1067,9 +1067,16 @@
 #           base snapshot did not match the base given for the current job or
 #           the crypt mode has changed.
 #
+# @missing-recreated: A bitmap for incremental backup was expected to be
+#     present, but was missing and thus got recreated. For example, this can
+#     happen if the drive was re-attached or if the bitmap was deleted for some
+#     other reason. PBS does not currently keep track of this; the backup-access
+#     mechanism does.
+#
 ##
 { 'enum': 'PBSBitmapAction',
-  'data': ['not-used', 'not-used-removed', 'new', 'used', 'invalid'] }
+  'data': ['not-used', 'not-used-removed', 'new', 'used', 'invalid',
+           'missing-recreated'] }
 
 ##
 # @PBSBitmapInfo:
-- 
2.39.5