[PATCH 3/8] asm-generic: add nommu implementations of __{get,put}_kernel_nofault

From: Christoph Hellwig
Date: Mon Sep 07 2020 - 01:59:39 EST


Add native implementations of __{get,put}_kernel_nofault using
{get,put}_unaligned, just like the {get,put}_user implementations.

Signed-off-by: Christoph Hellwig <hch@xxxxxx>
---
include/asm-generic/uaccess.h | 16 ++++++++++++++++
1 file changed, 16 insertions(+)

diff --git a/include/asm-generic/uaccess.h b/include/asm-generic/uaccess.h
index 6de5f524e9e631..b367f339be1a90 100644
--- a/include/asm-generic/uaccess.h
+++ b/include/asm-generic/uaccess.h
@@ -61,6 +61,22 @@ static inline int __put_user_fn(size_t size, void __user *to, void *from)
}
#define __put_user_fn(sz, u, k) __put_user_fn(sz, u, k)

+#define __get_kernel_nofault(dst, src, type, err_label) \
+do { \
+ *((type *)dst) = get_unaligned((type *)(src)); \
+ if (0) /* make sure the label looks used to the compiler */ \
+ goto err_label; \
+} while (0)
+
+#define __put_kernel_nofault(dst, src, type, err_label) \
+do { \
+ put_unaligned(*((type *)src), (type *)(dst)); \
+ if (0) /* make sure the label looks used to the compiler */ \
+ goto err_label; \
+} while (0)
+
+#define HAVE_GET_KERNEL_NOFAULT 1
+
static inline __must_check unsigned long
raw_copy_from_user(void *to, const void __user * from, unsigned long n)
{
--
2.28.0