From patchwork Fri Apr 15 03:27:57 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Fam Zheng X-Patchwork-Id: 8844581 Return-Path: X-Original-To: patchwork-qemu-devel@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork1.web.kernel.org (Postfix) with ESMTP id C0F969F3A0 for ; Fri, 15 Apr 2016 03:32:38 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 070E220373 for ; Fri, 15 Apr 2016 03:32:38 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 57815202F0 for ; Fri, 15 Apr 2016 03:32:37 +0000 (UTC) Received: from localhost ([::1]:52841 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aquUm-0003ja-K2 for patchwork-qemu-devel@patchwork.kernel.org; Thu, 14 Apr 2016 23:32:36 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:54082) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aquQr-0004RJ-Of for qemu-devel@nongnu.org; Thu, 14 Apr 2016 23:28:34 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1aquQq-00034t-Pd for qemu-devel@nongnu.org; Thu, 14 Apr 2016 23:28:33 -0400 Received: from mx1.redhat.com ([209.132.183.28]:55362) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aquQo-00033q-PB; Thu, 14 Apr 2016 23:28:30 -0400 Received: from int-mx11.intmail.prod.int.phx2.redhat.com (int-mx11.intmail.prod.int.phx2.redhat.com [10.5.11.24]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 6E1338AE72; Fri, 15 Apr 2016 03:28:30 +0000 (UTC) Received: from lemon.nay.redhat.com (dhcp-14-170.nay.redhat.com [10.66.14.170]) by int-mx11.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id u3F3S2RQ008188; Thu, 14 Apr 2016 23:28:27 -0400 From: Fam Zheng To: qemu-devel@nongnu.org Date: Fri, 15 Apr 2016 11:27:57 +0800 Message-Id: <1460690887-32751-8-git-send-email-famz@redhat.com> In-Reply-To: <1460690887-32751-1-git-send-email-famz@redhat.com> References: <1460690887-32751-1-git-send-email-famz@redhat.com> X-Scanned-By: MIMEDefang 2.68 on 10.5.11.24 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 209.132.183.28 Subject: [Qemu-devel] [PATCH for-2.7 v2 07/17] rbd: Implement image locking X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Kevin Wolf , qemu-block@nongnu.org, Jeff Cody , Markus Armbruster , Max Reitz , den@openvz.org, pbonzini@redhat.com, John Snow Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" X-Spam-Status: No, score=-6.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP librbd has the locking API that can be used to implement .bdrv_lockf. Signed-off-by: Fam Zheng --- block/rbd.c | 25 +++++++++++++++++++++++++ 1 file changed, 25 insertions(+) diff --git a/block/rbd.c b/block/rbd.c index 5bc5b32..a495083 100644 --- a/block/rbd.c +++ b/block/rbd.c @@ -810,6 +810,30 @@ static int qemu_rbd_truncate(BlockDriverState *bs, int64_t offset) return 0; } +static int qemu_rbd_lockf(BlockDriverState *bs, BdrvLockfCmd cmd) +{ + int ret; + BDRVRBDState *s = bs->opaque; + + /* XXX: RBD locks are not released automatically when program exits, which + * means if QEMU dies it cannot open the image next time until manually + * unlocked. */ + switch (cmd) { + case BDRV_LOCKF_RWLOCK: + ret = rbd_lock_exclusive(s->image, NULL); + break; + case BDRV_LOCKF_ROLOCK: + ret = rbd_lock_shared(s->image, NULL, NULL); + break; + case BDRV_LOCKF_UNLOCK: + ret = rbd_unlock(s->image, NULL); + break; + default: + abort(); + } + return ret; +} + static int qemu_rbd_snap_create(BlockDriverState *bs, QEMUSnapshotInfo *sn_info) { @@ -998,6 +1022,7 @@ static BlockDriver bdrv_rbd = { .bdrv_aio_discard = qemu_rbd_aio_discard, #endif + .bdrv_lockf = qemu_rbd_lockf, .bdrv_snapshot_create = qemu_rbd_snap_create, .bdrv_snapshot_delete = qemu_rbd_snap_remove, .bdrv_snapshot_list = qemu_rbd_snap_list,