Unverified Commit f289a348 authored by Christoph Hellwig's avatar Christoph Hellwig Committed by Palmer Dabbelt
Browse files

riscv: refactor __get_user and __put_user 



Add new __get_user_nocheck and __put_user_nocheck that switch on the size
and call the actual inline assembly helpers, and move the uaccess enable
/ disable into the actual __get_user and __put_user.  This prepares for
natively implementing __get_kernel_nofault and __put_kernel_nofault.

Also don't bother with the deprecated register keyword for the error
return.

Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Signed-off-by: default avatarPalmer Dabbelt <palmerdabbelt@google.com>
parent 11129e8e

arch/riscv/include/asm/uaccess.h

+52 −42
Original line number Diff line number Diff line
@@ -107,7 +107,6 @@ static inline int __access_ok(unsigned long addr, unsigned long size) 
do {								\

	uintptr_t __tmp;					\

	__typeof__(x) __x;					\

	__enable_user_access();					\

	__asm__ __volatile__ (					\

		"1:\n"						\

		"	" insn " %1, %3\n"			\
@@ -125,7 +124,6 @@ do { \ 
		"	.previous"				\

		: "+r" (err), "=&r" (__x), "=r" (__tmp)		\

		: "m" (*(ptr)), "i" (-EFAULT));			\

	__disable_user_access();				\

	(x) = __x;						\

} while (0)
@@ -138,7 +136,6 @@ do { \ 
	u32 __user *__ptr = (u32 __user *)(ptr);		\

	u32 __lo, __hi;						\

	uintptr_t __tmp;					\

	__enable_user_access();					\

	__asm__ __volatile__ (					\

		"1:\n"						\

		"	lw %1, %4\n"				\
@@ -162,12 +159,30 @@ do { \ 
			"=r" (__tmp)				\

		: "m" (__ptr[__LSW]), "m" (__ptr[__MSW]),	\

			"i" (-EFAULT));				\

	__disable_user_access();				\

	(x) = (__typeof__(x))((__typeof__((x)-(x)))(		\

		(((u64)__hi << 32) | __lo)));			\

} while (0)

#endif /* CONFIG_64BIT */



#define __get_user_nocheck(x, __gu_ptr, __gu_err)		\

do {								\

	switch (sizeof(*__gu_ptr)) {				\

	case 1:							\

		__get_user_asm("lb", (x), __gu_ptr, __gu_err);	\

		break;						\

	case 2:							\

		__get_user_asm("lh", (x), __gu_ptr, __gu_err);	\

		break;						\

	case 4:							\

		__get_user_asm("lw", (x), __gu_ptr, __gu_err);	\

		break;						\

	case 8:							\

		__get_user_8((x), __gu_ptr, __gu_err);	\

		break;						\

	default:						\

		BUILD_BUG();					\

	}							\

} while (0)



/**

 * __get_user: - Get a simple variable from user space, with less checking.
@@ -191,25 +206,15 @@ do { \ 
 */

#define __get_user(x, ptr)					\

({								\

	register long __gu_err = 0;				\

	const __typeof__(*(ptr)) __user *__gu_ptr = (ptr);	\

	long __gu_err = 0;					\

								\

	__chk_user_ptr(__gu_ptr);				\

	switch (sizeof(*__gu_ptr)) {				\

	case 1:							\

		__get_user_asm("lb", (x), __gu_ptr, __gu_err);	\

		break;						\

	case 2:							\

		__get_user_asm("lh", (x), __gu_ptr, __gu_err);	\

		break;						\

	case 4:							\

		__get_user_asm("lw", (x), __gu_ptr, __gu_err);	\

		break;						\

	case 8:							\

		__get_user_8((x), __gu_ptr, __gu_err);	\

		break;						\

	default:						\

		BUILD_BUG();					\

	}							\

								\

	__enable_user_access();					\

	__get_user_nocheck(x, __gu_ptr, __gu_err);		\

	__disable_user_access();				\

								\

	__gu_err;						\

})
@@ -243,7 +248,6 @@ do { \ 
do {								\

	uintptr_t __tmp;					\

	__typeof__(*(ptr)) __x = x;				\

	__enable_user_access();					\

	__asm__ __volatile__ (					\

		"1:\n"						\

		"	" insn " %z3, %2\n"			\
@@ -260,7 +264,6 @@ do { \ 
		"	.previous"				\

		: "+r" (err), "=r" (__tmp), "=m" (*(ptr))	\

		: "rJ" (__x), "i" (-EFAULT));			\

	__disable_user_access();				\

} while (0)



#ifdef CONFIG_64BIT
@@ -272,7 +275,6 @@ do { \ 
	u32 __user *__ptr = (u32 __user *)(ptr);		\

	u64 __x = (__typeof__((x)-(x)))(x);			\

	uintptr_t __tmp;					\

	__enable_user_access();					\

	__asm__ __volatile__ (					\

		"1:\n"						\

		"	sw %z4, %2\n"				\
@@ -294,10 +296,28 @@ do { \ 
			"=m" (__ptr[__LSW]),			\

			"=m" (__ptr[__MSW])			\

		: "rJ" (__x), "rJ" (__x >> 32), "i" (-EFAULT));	\

	__disable_user_access();				\

} while (0)

#endif /* CONFIG_64BIT */



#define __put_user_nocheck(x, __gu_ptr, __pu_err)					\

do {								\

	switch (sizeof(*__gu_ptr)) {				\

	case 1:							\

		__put_user_asm("sb", (x), __gu_ptr, __pu_err);	\

		break;						\

	case 2:							\

		__put_user_asm("sh", (x), __gu_ptr, __pu_err);	\

		break;						\

	case 4:							\

		__put_user_asm("sw", (x), __gu_ptr, __pu_err);	\

		break;						\

	case 8:							\

		__put_user_8((x), __gu_ptr, __pu_err);	\

		break;						\

	default:						\

		BUILD_BUG();					\

	}							\

} while (0)



/**

 * __put_user: - Write a simple value into user space, with less checking.
@@ -320,25 +340,15 @@ do { \ 
 */

#define __put_user(x, ptr)					\

({								\

	register long __pu_err = 0;				\

	__typeof__(*(ptr)) __user *__gu_ptr = (ptr);		\

	long __pu_err = 0;					\

								\

	__chk_user_ptr(__gu_ptr);				\

	switch (sizeof(*__gu_ptr)) {				\

	case 1:							\

		__put_user_asm("sb", (x), __gu_ptr, __pu_err);	\

		break;						\

	case 2:							\

		__put_user_asm("sh", (x), __gu_ptr, __pu_err);	\

		break;						\

	case 4:							\

		__put_user_asm("sw", (x), __gu_ptr, __pu_err);	\

		break;						\

	case 8:							\

		__put_user_8((x), __gu_ptr, __pu_err);	\

		break;						\

	default:						\

		BUILD_BUG();					\

	}							\

								\

	__enable_user_access();					\

	__put_user_nocheck(x, __gu_ptr, __pu_err);		\

	__disable_user_access();				\

								\

	__pu_err;						\

})

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