From mboxrd@z Thu Jan 1 00:00:00 1970 From: Josh Durgin Subject: Re: [PATCH 6/7] rbd: return obj version in __rbd_refresh_header() Date: Mon, 30 Jul 2012 14:32:44 -0700 Message-ID: <5016FD7C.2040306@inktank.com> References: <50119421.1090702@inktank.com> <501195D6.4000609@inktank.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from mail-pb0-f46.google.com ([209.85.160.46]:41468 "EHLO mail-pb0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754526Ab2G3Vcr (ORCPT ); Mon, 30 Jul 2012 17:32:47 -0400 Received: by pbbrp8 with SMTP id rp8so10459595pbb.19 for ; Mon, 30 Jul 2012 14:32:46 -0700 (PDT) In-Reply-To: <501195D6.4000609@inktank.com> Sender: ceph-devel-owner@vger.kernel.org List-ID: To: Alex Elder Cc: ceph-devel@vger.kernel.org On 07/26/2012 12:09 PM, Alex Elder wrote: > Add a new parameter to __rbd_refresh_header() through which the > version of the header object is passed back to the caller. In most > cases this isn't needed. The main motivation is to normalize > (almost) all calls to __rbd_refresh_header() so they are all > wrapped immediately by mutex_lock()/mutex_unlock(). > > Signed-off-by: Alex Elder Reviewed-by: Josh Durgin > --- > drivers/block/rbd.c | 25 +++++++++++-------------- > 1 file changed, 11 insertions(+), 14 deletions(-) > > diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c > index 3daf8fb..31be4ca 100644 > --- a/drivers/block/rbd.c > +++ b/drivers/block/rbd.c > @@ -240,7 +240,7 @@ static void rbd_put_dev(struct rbd_device *rbd_dev) > put_device(&rbd_dev->dev); > } > > -static int __rbd_refresh_header(struct rbd_device *rbd_dev); > +static int __rbd_refresh_header(struct rbd_device *rbd_dev, u64 *hver); > > static int rbd_open(struct block_device *bdev, fmode_t mode) > { > @@ -1223,8 +1223,7 @@ static void rbd_watch_cb(u64 ver, u64 notify_id, > u8 opcode, void *data) > dout("rbd_watch_cb %s notify_id=%lld opcode=%d\n", > rbd_dev->header_name, notify_id, (int) opcode); > mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING); > - rc = __rbd_refresh_header(rbd_dev); > - hver = rbd_dev->header.obj_version; > + rc = __rbd_refresh_header(rbd_dev, &hver); > mutex_unlock(&ctl_mutex); > if (rc) > pr_warning(RBD_DRV_NAME "%d got notification but failed to " > @@ -1702,7 +1701,7 @@ static void __rbd_remove_all_snaps(struct > rbd_device *rbd_dev) > /* > * only read the first part of the ondisk header, without the snaps info > */ > -static int __rbd_refresh_header(struct rbd_device *rbd_dev) > +static int __rbd_refresh_header(struct rbd_device *rbd_dev, u64 *hver) > { > int ret; > struct rbd_image_header h; > @@ -1727,6 +1726,8 @@ static int __rbd_refresh_header(struct rbd_device > *rbd_dev) > /* osd requests may still refer to snapc */ > ceph_put_snap_context(rbd_dev->header.snapc); > > + if (hver) > + *hver = h.obj_version; > rbd_dev->header.obj_version = h.obj_version; > rbd_dev->header.image_size = h.image_size; > rbd_dev->header.total_snaps = h.total_snaps; > @@ -1896,17 +1897,13 @@ static ssize_t rbd_image_refresh(struct device *dev, > size_t size) > { > struct rbd_device *rbd_dev = dev_to_rbd_dev(dev); > - int rc; > - int ret = size; > + int ret; > > mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING); > - > - rc = __rbd_refresh_header(rbd_dev); > - if (rc < 0) > - ret = rc; > - > + ret = __rbd_refresh_header(rbd_dev, NULL); > mutex_unlock(&ctl_mutex); > - return ret; > + > + return ret < 0 ? ret : size; > } > > static DEVICE_ATTR(size, S_IRUGO, rbd_size_show, NULL); > @@ -2195,7 +2192,7 @@ static int rbd_init_watch_dev(struct rbd_device > *rbd_dev) > ret = rbd_req_sync_watch(rbd_dev); > if (ret == -ERANGE) { > mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING); > - rc = __rbd_refresh_header(rbd_dev); > + rc = __rbd_refresh_header(rbd_dev, NULL); > mutex_unlock(&ctl_mutex); > if (rc < 0) > return rc; > @@ -2645,7 +2642,7 @@ static ssize_t rbd_snap_add(struct device *dev, > if (ret < 0) > goto err_unlock; > > - ret = __rbd_refresh_header(rbd_dev); > + ret = __rbd_refresh_header(rbd_dev, NULL); > if (ret < 0) > goto err_unlock; >