From patchwork Thu Nov 8 14:11:53 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alex Elder X-Patchwork-Id: 1716111 Return-Path: X-Original-To: patchwork-ceph-devel@patchwork.kernel.org Delivered-To: patchwork-process-083081@patchwork2.kernel.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by patchwork2.kernel.org (Postfix) with ESMTP id 3A4ECDF280 for ; Thu, 8 Nov 2012 14:11:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755959Ab2KHOLy (ORCPT ); Thu, 8 Nov 2012 09:11:54 -0500 Received: from mail-ie0-f174.google.com ([209.85.223.174]:57441 "EHLO mail-ie0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755644Ab2KHOLx (ORCPT ); Thu, 8 Nov 2012 09:11:53 -0500 Received: by mail-ie0-f174.google.com with SMTP id k13so4184469iea.19 for ; Thu, 08 Nov 2012 06:11:53 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20120113; h=message-id:date:from:user-agent:mime-version:to:subject:references :in-reply-to:content-type:content-transfer-encoding :x-gm-message-state; bh=fWyNB3DcbrmYk6uwpkvQm15GuMv/VPRMfXTR7EPLEMM=; b=jqnZuEKx1UYSGPW+pmBTxDZ9AF96+Fc+BLqpgVEXmFiAl1fbQzXl25NNV+VyWQdkWa n9x11FQsZhByKrjCkKzpBdCiUs0fVYP7u8IaxbC4ON/4W1/rmnzGHn8LTpvyVKHxrAvd 1Mj2wCKVItwIj7zGpmPUjfR2Cynv1O7SVUzgz8nCof2RyuIuN1atxGC6xOE9/dZfeaoa 7j3y964p/GQnFomLgXbYAIYPxFc7iZSf3aVe+cobY5Mf2MuF7aRMHHgcJ5FFH0rPgUYj FNygJi1o6uq7uEmNR5E3vcts/XG8aBmqk6O7cWlPb4/wm6VYtHS9faP6rJBzVrQY0m5U eokQ== Received: by 10.42.37.17 with SMTP id w17mr7095611icd.32.1352383913269; Thu, 08 Nov 2012 06:11:53 -0800 (PST) Received: from [172.22.22.4] (c-71-195-31-37.hsd1.mn.comcast.net. [71.195.31.37]) by mx.google.com with ESMTPS id pq3sm4460101igc.8.2012.11.08.06.11.51 (version=SSLv3 cipher=OTHER); Thu, 08 Nov 2012 06:11:52 -0800 (PST) Message-ID: <509BBDA9.7090403@inktank.com> Date: Thu, 08 Nov 2012 08:11:53 -0600 From: Alex Elder User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:16.0) Gecko/20121028 Thunderbird/16.0.2 MIME-Version: 1.0 To: "ceph-devel@vger.kernel.org" Subject: [PATCH 2/2] rbd: a little more cleanup of rbd_rq_fn() References: <509BBD50.3010102@inktank.com> In-Reply-To: <509BBD50.3010102@inktank.com> X-Gm-Message-State: ALoCoQlHb39zsI5xhN28ASyF5GGxcM35SftaZ6xPD+Ofe8WqB/4fSrJjRGU6+VOX3qs+Xo3/10RG Sender: ceph-devel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: ceph-devel@vger.kernel.org Now that a big hunk in the middle of rbd_rq_fn() has been moved into its own routine we can simplify it a little more. Signed-off-by: Alex Elder --- drivers/block/rbd.c | 50 +++++++++++++++++++++++--------------------------- 1 file changed, 23 insertions(+), 27 deletions(-) diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c index 6aed59b..fb727c0 100644 --- a/drivers/block/rbd.c +++ b/drivers/block/rbd.c @@ -1649,53 +1649,49 @@ static int rbd_dev_do_request(struct request *rq, static void rbd_rq_fn(struct request_queue *q) { struct rbd_device *rbd_dev = q->queuedata; + bool read_only = rbd_dev->mapping.read_only; struct request *rq; while ((rq = blk_fetch_request(q))) { - struct bio *bio; - bool do_write; - unsigned int size; - u64 ofs; - struct ceph_snap_context *snapc; + struct ceph_snap_context *snapc = NULL; int result; dout("fetched request\n"); - /* filter out block requests we don't understand */ + /* Filter out block requests we don't understand */ + if ((rq->cmd_type != REQ_TYPE_FS)) { __blk_end_request_all(rq, 0); continue; } + spin_unlock_irq(q->queue_lock); - /* deduce our operation (read, write) */ - do_write = (rq_data_dir(rq) == WRITE); - if (do_write && rbd_dev->mapping.read_only) { - __blk_end_request_all(rq, -EROFS); - continue; - } + /* Stop writes to a read-only device */ - spin_unlock_irq(q->queue_lock); + result = -EROFS; + if (read_only && rq_data_dir(rq) == WRITE) + goto out_end_request; + + /* Grab a reference to the snapshot context */ down_read(&rbd_dev->header_rwsem); + if (rbd_dev->exists) { + snapc = ceph_get_snap_context(rbd_dev->header.snapc); + rbd_assert(snapc != NULL); + } + up_read(&rbd_dev->header_rwsem); - if (!rbd_dev->exists) { + if (!snapc) { rbd_assert(rbd_dev->spec->snap_id != CEPH_NOSNAP); - up_read(&rbd_dev->header_rwsem); dout("request for non-existent snapshot"); - spin_lock_irq(q->queue_lock); - __blk_end_request_all(rq, -ENXIO); - continue; + result = -ENXIO; + goto out_end_request; } - snapc = ceph_get_snap_context(rbd_dev->header.snapc); - - up_read(&rbd_dev->header_rwsem); - - size = blk_rq_bytes(rq); - ofs = blk_rq_pos(rq) * SECTOR_SIZE; - bio = rq->bio; - - result = rbd_dev_do_request(rq, rbd_dev, snapc, ofs, size, bio); + result = rbd_dev_do_request(rq, rbd_dev, snapc, + blk_rq_pos(rq) * SECTOR_SIZE, + blk_rq_bytes(rq), rq->bio); +out_end_request: ceph_put_snap_context(snapc); spin_lock_irq(q->queue_lock); if (result < 0)