librbd/object_map: rbd diff between two snapshots lists entire image content

Problem:
rbd diff between two snapshots lists entire image content with `whole-object` switch.

Solution:
While computing resize diff during object map do not mark state as new data
unless diff state is valid.

Fixes: https://tracker.ceph.com/issues/50787
Signed-off-by: Sunny Kumar <sunkumar@redhat.com>

diff --git a/src/librbd/object_map/DiffRequest.cc b/src/librbd/object_map/DiffRequest.cc
index ca341f78c2f28b151731c6699df8f4ecc309ef79..606d48bbf33c4d6eb9343a5b1735af47ee21cc8c 100644 (file)
--- a/src/librbd/object_map/DiffRequest.cc
+++ b/src/librbd/object_map/DiffRequest.cc
@@ -222,7 +222,9 @@ void DiffRequest<I>::handle_load_object_map(int r) {
       uint8_t object_map_state = *it;
       if (object_map_state == OBJECT_NONEXISTENT) {
         *diff_it = DIFF_STATE_HOLE;
-      } else if (diff_from_start || object_map_state != OBJECT_EXISTS_CLEAN) {
+      } else if (diff_from_start ||
+                 (m_object_diff_state_valid &&
+                  object_map_state != OBJECT_EXISTS_CLEAN)) {
         *diff_it = DIFF_STATE_DATA_UPDATED;
       } else {
         *diff_it = DIFF_STATE_DATA;