From: Casey Bodley <cbodley@redhat.com>
Date: Mon, 22 Aug 2022 19:57:39 +0000 (-0400)
Subject: cls/rgw: restore backward-compatible encoding of cls_rgw_bucket_instance_entry
X-Git-Tag: v18.0.0~168^2
X-Git-Url: http://git.apps.os.sepia.ceph.com/?a=commitdiff_plain;h=c1bb5feef75314576af6a427b73ec223ad1fd5e3;p=ceph-ci.git

cls/rgw: restore backward-compatible encoding of cls_rgw_bucket_instance_entry

the encoding of `cls_rgw_bucket_instance_entry` changed in
bd0b0e5d984c83504f88fa155a7dfc6f6571aa49 such that pacific/quincy
OSDs cannot read the version written by reef OSDs

two fields (bucket_instance_id and num_shards) were removed in the v2
encoder, but the v1 decoder still expects them to be present

since we haven't released reef yet, we can fix this with a v3 that adds
the fields back

Fixes: https://tracker.ceph.com/issues/57232

Signed-off-by: Casey Bodley <cbodley@redhat.com>
---

diff --git a/src/cls/rgw/cls_rgw_types.h b/src/cls/rgw/cls_rgw_types.h
index 186c25dbb5e..fdf4b9427a9 100644
--- a/src/cls/rgw/cls_rgw_types.h
+++ b/src/cls/rgw/cls_rgw_types.h
@@ -806,17 +806,23 @@ struct cls_rgw_bucket_instance_entry {
   cls_rgw_reshard_status reshard_status{RESHARD_STATUS::NOT_RESHARDING};
 
   void encode(ceph::buffer::list& bl) const {
-    ENCODE_START(2, 1, bl);
+    ENCODE_START(3, 1, bl);
     encode((uint8_t)reshard_status, bl);
+    { // fields removed in v2 but added back as empty in v3
+      std::string bucket_instance_id;
+      encode(bucket_instance_id, bl);
+      int32_t num_shards{-1};
+      encode(num_shards, bl);
+    }
     ENCODE_FINISH(bl);
   }
 
   void decode(ceph::buffer::list::const_iterator& bl) {
-    DECODE_START(2, bl);
+    DECODE_START(3, bl);
     uint8_t s;
     decode(s, bl);
     reshard_status = (cls_rgw_reshard_status)s;
-    if (struct_v < 2) { // fields removed from v2
+    if (struct_v != 2) { // fields removed from v2, added back in v3
       std::string bucket_instance_id;
       decode(bucket_instance_id, bl);
       int32_t num_shards{-1};