Check if user is already logged in for DAV auth, instead of logging in and creating new sessions for every request

lib/connector/sabre/auth.php

@@ -31,6 +31,10 @@ class OC_Connector_Sabre_Auth extends Sabre_DAV_Auth_Backend_AbstractBasic {
 	 * @return bool
 	 */
 	protected function validateUserPass($username, $password){
+		if (OC_User::isLoggedIn()) {
+			OC_Util::setupFS($username);
+			return true;
+		} else {
 			OC_Util::setUpFS();//login hooks may need early access to the filesystem
 			if(OC_User::login($username,$password)){
 				OC_Util::setUpFS($username);
@@ -40,4 +44,5 @@ class OC_Connector_Sabre_Auth extends Sabre_DAV_Auth_Backend_AbstractBasic {
 				return false;
 			}
 		}
+	}
 }