Xen: consolidate and simplify struct xenbus_driver instantiation

The 'name', 'owner', and 'mod_name' members are redundant with the
identically named fields in the 'driver' sub-structure. Rather than
switching each instance to specify these fields explicitly, introduce
a macro to simplify this.

Eliminate further redundancy by allowing the drvname argument to
DEFINE_XENBUS_DRIVER() to be blank (in which case the first entry from
the ID table will be used for .driver.name).

Also eliminate the questionable xenbus_register_{back,front}end()
wrappers - their sole remaining purpose was the checking of the
'owner' field, proper setting of which shouldn't be an issue anymore
when the macro gets used.

v2: Restore DRV_NAME for the driver name in xen-pciback.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: Florian Tobias Schandinat <FlorianSchandinat@gmx.de>
Cc: Ian Campbell <ian.campbell@citrix.com>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>

2 files changed, 6 insertions, 12 deletions

diff --git a/drivers/net/xen-netback/xenbus.c b/drivers/net/xen-netback/xenbus.c
index 1ce729d6af75..410018c4c528 100644
--- a/drivers/net/xen-netback/xenbus.c
+++ b/drivers/net/xen-netback/xenbus.c
@@ -474,17 +474,14 @@ static const struct xenbus_device_id netback_ids[] = {
 };
 
 
-static struct xenbus_driver netback = {
-        .name = "vif",
-        .owner = THIS_MODULE,
-        .ids = netback_ids,
+static DEFINE_XENBUS_DRIVER(netback, ,
         .probe = netback_probe,
         .remove = netback_remove,
         .uevent = netback_uevent,
         .otherend_changed = frontend_changed,
-};
+);
 
 int xenvif_xenbus_init(void)
 {
-        return xenbus_register_backend(&netback);
+        return xenbus_register_backend(&netback_driver);
 }
diff --git a/drivers/net/xen-netfront.c b/drivers/net/xen-netfront.c
index 226faab23603..81ff5a749279 100644
--- a/drivers/net/xen-netfront.c
+++ b/drivers/net/xen-netfront.c
@@ -1910,7 +1910,7 @@ static void xennet_sysfs_delif(struct net_device *netdev)
 
 #endif /* CONFIG_SYSFS */
 
-static struct xenbus_device_id netfront_ids[] = {
+static const struct xenbus_device_id netfront_ids[] = {
         { "vif" },
         { "" }
 };
@@ -1937,15 +1937,12 @@ static int __devexit xennet_remove(struct xenbus_device *dev)
         return 0;
 }
 
-static struct xenbus_driver netfront_driver = {
-        .name = "vif",
-        .owner = THIS_MODULE,
-        .ids = netfront_ids,
+static DEFINE_XENBUS_DRIVER(netfront, ,
         .probe = netfront_probe,
         .remove = __devexit_p(xennet_remove),
         .resume = netfront_resume,
         .otherend_changed = netback_changed,
-};
+);
 
 static int __init netif_init(void)
 {