vringh: kill off ACCESS_ONCE()

Despite living under drivers/ vringh.c is also used as part of the userspace
virtio tools. Before we can kill off the ACCESS_ONCE()definition in the tools,
we must convert vringh.c to use {READ,WRITE}_ONCE().

This patch does so, along with the required include of <linux/compiler.h> for
the relevant definitions. The userspace tools provide their own definitions in
their own <linux/compiler.h>.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: kvm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: netdev@vger.kernel.org
Cc: virtualization@lists.linux-foundation.org
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Jason Wang <jasowang@redhat.com>
This commit is contained in:
Mark Rutland 2016-11-24 10:25:13 +00:00 committed by Michael S. Tsirkin
parent 5da889c795
commit 9d1b972f8a

View File

@ -3,6 +3,7 @@
*
* Since these may be in userspace, we use (inline) accessors.
*/
#include <linux/compiler.h>
#include <linux/module.h>
#include <linux/vringh.h>
#include <linux/virtio_ring.h>
@ -820,13 +821,13 @@ EXPORT_SYMBOL(vringh_need_notify_user);
static inline int getu16_kern(const struct vringh *vrh,
u16 *val, const __virtio16 *p)
{
*val = vringh16_to_cpu(vrh, ACCESS_ONCE(*p));
*val = vringh16_to_cpu(vrh, READ_ONCE(*p));
return 0;
}
static inline int putu16_kern(const struct vringh *vrh, __virtio16 *p, u16 val)
{
ACCESS_ONCE(*p) = cpu_to_vringh16(vrh, val);
WRITE_ONCE(*p, cpu_to_vringh16(vrh, val));
return 0;
}