fix for spreading ec shards

weed/server/volume_grpc_erasure_coding.go

@@ -143,10 +143,17 @@ func (vs *VolumeServer) VolumeEcShardsCopy(ctx context.Context, req *volume_serv
 
 	glog.V(0).Infof("VolumeEcShardsCopy: %v", req)
 
-	location := vs.store.FindFreeLocation(func(location *storage.DiskLocation) bool {
-		_, found := location.FindEcVolume(needle.VolumeId(req.VolumeId))
-		return found
-	})
+	var location *storage.DiskLocation
+	if req.CopyEcxFile {
+		location = vs.store.FindFreeLocation(func(location *storage.DiskLocation) bool {
+			return location.DiskType == types.HardDriveType
+		})
+	} else {
+		location = vs.store.FindFreeLocation(func(location *storage.DiskLocation) bool {
+			_, found := location.FindEcVolume(needle.VolumeId(req.VolumeId))
+			return found
+		})
+	}
 	if location == nil {
 		return nil, fmt.Errorf("no space left")
 	}