rgw: use bucket_info.bucket_id instead of marker where needed

We used to use these interchangeably, but they actually have diffent meaning.
The marker is the prefix we assign to the objects in this bucket, whereas
the bucket_id is the bucket instance's id. These used to hold the same
value, but with bucket resharding it's not going to be true anymore.

Signed-off-by: Yehuda Sadeh <yehuda@redhat.com>
(cherry picked from commit 94afaf7)
See: http://tracker.ceph.com/issues/17556
See: #11368
Signed-off-by: Robin H. Johnson <robin.johnson@dreamhost.com>

src/rgw/rgw_rados.cc

@@ -5112,14 +5112,23 @@ int RGWRados::init_bucket_index(rgw_bucket& bucket, int num_shards)
     return r;
 
   string dir_oid =  dir_oid_prefix;
-  dir_oid.append(bucket.marker);
+  dir_oid.append(bucket.bucket_id);
 
   map<int, string> bucket_objs;
   get_bucket_index_objects(dir_oid, num_shards, bucket_objs);
 
   return CLSRGWIssueBucketIndexInit(index_ctx, bucket_objs, cct->_conf->rgw_bucket_index_max_aio)();
 }
 
+void RGWRados::create_bucket_id(string *bucket_id)
+{
+  uint64_t iid = instance_id();
+  uint64_t bid = next_bucket_id();
+  char buf[get_zone_params().get_id().size() + 48];
+  snprintf(buf, sizeof(buf), "%s.%llu.%llu", get_zone_params().get_id().c_str(), (long long)iid, (long long)bid);
+  *bucket_id = buf;
+}
+
 /**
  * create a bucket with name bucket and the given list of attrs
  * returns 0 on success, -ERR# otherwise.
@@ -7518,13 +7527,13 @@ int RGWRados::open_bucket_index(rgw_bucket& bucket, librados::IoCtx& index_ctx,
   if (r < 0)
     return r;
 
-  if (bucket.marker.empty()) {
-    ldout(cct, 0) << "ERROR: empty marker for bucket operation" << dendl;
+  if (bucket.bucket_id.empty()) {
+    ldout(cct, 0) << "ERROR: empty bucket id for bucket operation" << dendl;
     return -EIO;
   }
 
   bucket_oid = dir_oid_prefix;
-  bucket_oid.append(bucket.marker);
+  bucket_oid.append(bucket.bucket_id);
 
   return 0;
 }
@@ -7535,13 +7544,13 @@ int RGWRados::open_bucket_index_base(rgw_bucket& bucket, librados::IoCtx& index_
   if (r < 0)
     return r;
 
-  if (bucket.marker.empty()) {
-    ldout(cct, 0) << "ERROR: empty marker for bucket operation" << dendl;
+  if (bucket.bucket_id.empty()) {
+    ldout(cct, 0) << "ERROR: empty bucket_id for bucket operation" << dendl;
     return -EIO;
   }
 
   bucket_oid_base = dir_oid_prefix;
-  bucket_oid_base.append(bucket.marker);
+  bucket_oid_base.append(bucket.bucket_id);
 
   return 0;