From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alex Elder Subject: [PATCH 0/2] libceph: osd_client should not take bio reference Date: Wed, 30 Jan 2013 14:47:32 -0600 Message-ID: <510986E4.7050901@inktank.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: Received: from mail-ia0-f173.google.com ([209.85.210.173]:36505 "EHLO mail-ia0-f173.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751515Ab3A3Ur3 (ORCPT ); Wed, 30 Jan 2013 15:47:29 -0500 Received: by mail-ia0-f173.google.com with SMTP id l29so2962545iag.18 for ; Wed, 30 Jan 2013 12:47:29 -0800 (PST) Sender: ceph-devel-owner@vger.kernel.org List-ID: To: "ceph-devel@vger.kernel.org" Currently when the osd client gets a request that involves a bio list, it assumes the initiator (the rbd client) has taken an extra reference to the first bio on that list. When the request is done, the initiator calls ceph_osdc_release_request() and at that time the osd client drops that presumed reference. The second patch in this series simply gets rid of that extra reference entirely, because it's not needed. Doing this creates an incompatibility between differing versions of both rbd and the osd client (libceph). So The first patch adds a simple compatibility check capability so it's possible to avoid that causing any problems. -Alex [PATCH 1/2] libceph: add a compatibility check interface [PATCH 2/2] rbd: don't take extra bio reference for osd client