rgw, cls_rgw: clean up olh artifacts when dropping last version

This is still missing one piece, however, it works like this:
1. bucket index log reflects last version was removed (already did that)
2. olh entry is marked as 'pending removal'
 - any new versions coming in now to the olh entry will clear pending
   state
3. rgw conditionally removes olh object (still missing condition check)
 - condition checks should verify olh tag & version, and no pending
   modifications
4. if (2) is successful, rgw sends 'clear olh' request to bucket index
5. bucket index, if still 'pending removal' clears olh and plain entry

Signed-off-by: Yehuda Sadeh <yehuda@redhat.com>

1 files changed, 17 insertions, 0 deletions

diff --git a/src/cls/rgw/cls_rgw_client.cc b/src/cls/rgw/cls_rgw_client.cc
index e78d77a192b..ab8b9a2981e 100644
--- a/src/cls/rgw/cls_rgw_client.cc
+++ b/src/cls/rgw/cls_rgw_client.cc
@@ -258,6 +258,23 @@ void cls_rgw_trim_olh_log(librados::ObjectWriteOperation& op, string& oid, const
   op.exec("rgw", "bucket_trim_olh_log", in);
 }
 
+int cls_rgw_clear_olh(IoCtx& io_ctx, string& oid, const cls_rgw_obj_key& olh, const string& olh_tag)
+{
+  bufferlist in, out;
+  struct rgw_cls_bucket_clear_olh_op call;
+  call.key = olh;
+  call.olh_tag = olh_tag;
+  ::encode(call, in);
+  librados::ObjectWriteOperation op;
+  int op_ret;
+  op.exec("rgw", "bucket_clear_olh", in, &out, &op_ret);
+  int r = io_ctx.operate(oid, &op);
+  if (r < 0) {
+    return r;
+  }
+  return op_ret;
+}
+
 int cls_rgw_bucket_check_index_op(IoCtx& io_ctx, string& oid,
 				  rgw_bucket_dir_header *existing_header,
 				  rgw_bucket_dir_header *calculated_header)