[PATCH 3/3] tools/virtio: use {READ,WRITE}_ONCE() in uaccess.h
From: Mark Rutland <mark.rutland@arm.com>
Date: 2016-11-24 10:25:45
Also in:
kvm, lkml
Subsystem:
the rest, virtio core · Maintainers:
Linus Torvalds, "Michael S. Tsirkin", Jason Wang
As a step towards killing off ACCESS_ONCE, use {READ,WRITE}_ONCE() for the
virtio tools uaccess primitives, pulling these in from <linux/compiler.h>.
With this done, we can kill off the now-unused ACCESS_ONCE() definition.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: linux-kernel@vger.kernel.org
Cc: virtualization@lists.linux-foundation.org
---
tools/virtio/linux/uaccess.h | 9 +++++----
1 file changed, 5 insertions(+), 4 deletions(-)
diff --git a/tools/virtio/linux/uaccess.h b/tools/virtio/linux/uaccess.h
index 0a578fe..fa05d01 100644
--- a/tools/virtio/linux/uaccess.h
+++ b/tools/virtio/linux/uaccess.h@@ -1,8 +1,9 @@ #ifndef UACCESS_H #define UACCESS_H -extern void *__user_addr_min, *__user_addr_max; -#define ACCESS_ONCE(x) (*(volatile typeof(x) *)&(x)) +#include <linux/compiler.h> + +extern void *__user_addr_min, *__user_addr_max; static inline void __chk_user_ptr(const volatile void *p, size_t size) {
@@ -13,7 +14,7 @@ static inline void __chk_user_ptr(const volatile void *p, size_t size) ({ \ typeof(ptr) __pu_ptr = (ptr); \ __chk_user_ptr(__pu_ptr, sizeof(*__pu_ptr)); \ - ACCESS_ONCE(*(__pu_ptr)) = x; \ + WRITE_ONCE(*(__pu_ptr), x); \ 0; \ })
@@ -21,7 +22,7 @@ static inline void __chk_user_ptr(const volatile void *p, size_t size) ({ \ typeof(ptr) __pu_ptr = (ptr); \ __chk_user_ptr(__pu_ptr, sizeof(*__pu_ptr)); \ - x = ACCESS_ONCE(*(__pu_ptr)); \ + x = READ_ONCE(*(__pu_ptr)); \ 0; \ })
--
2.7.4