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>

1 files changed, 3 insertions, 6 deletions

diff --git a/drivers/block/xen-blkback/xenbus.c b/drivers/block/xen-blkback/xenbus.c
index f759ad4584c..edbb69ebdf2 100644
--- a/drivers/block/xen-blkback/xenbus.c
+++ b/drivers/block/xen-blkback/xenbus.c
@@ -787,17 +787,14 @@ static const struct xenbus_device_id xen_blkbk_ids[] = {
 };
 
 
-static struct xenbus_driver xen_blkbk = {
-	.name = "vbd",
-	.owner = THIS_MODULE,
-	.ids = xen_blkbk_ids,
+static DEFINE_XENBUS_DRIVER(xen_blkbk, ,
 	.probe = xen_blkbk_probe,
 	.remove = xen_blkbk_remove,
 	.otherend_changed = frontend_changed
-};
+);
 
 
 int xen_blkif_xenbus_init(void)
 {
-	return xenbus_register_backend(&xen_blkbk);
+	return xenbus_register_backend(&xen_blkbk_driver);
 }