From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alex Elder Subject: [PATCH 2/2] rbd: a little more cleanup of rbd_rq_fn() Date: Thu, 08 Nov 2012 08:11:53 -0600 Message-ID: <509BBDA9.7090403@inktank.com> References: <509BBD50.3010102@inktank.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: 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) In-Reply-To: <509BBD50.3010102@inktank.com> Sender: ceph-devel-owner@vger.kernel.org List-ID: To: "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) -- 1.7.9.5