Commit ee7b5d75 authored by Tong Tiangen's avatar Tong Tiangen Committed by Ma Wupeng
Browse files

arm64: introduce copy_mc_to_kernel() implementation 

hulk inclusion
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I5GB28


CVE: NA

-------------------------------

The copy_mc_to_kernel() helper is memory copy implementation that handles
source exceptions. It can be used in memory copy scenarios that tolerate
hardware memory errors(e.g: pmem_read/dax_copy_to_iter).

Currnently, only x86 and ppc suuport this helper, after arm64 support
machine check safe framework, we introduce copy_mc_to_kernel()
implementation.

Signed-off-by: default avatarTong Tiangen <tongtiangen@huawei.com>
parent b32f46c2

arch/arm64/include/asm/string.h

+5 −0
Original line number Diff line number Diff line
@@ -35,6 +35,10 @@ extern void *memchr(const void *, int, __kernel_size_t); 
extern void *memcpy(void *, const void *, __kernel_size_t);

extern void *__memcpy(void *, const void *, __kernel_size_t);



#define __HAVE_ARCH_MEMCPY_MC

extern unsigned long *memcpy_mcs(void *, const void *, __kernel_size_t);

extern unsigned long *__memcpy_mcs(void *, const void *, __kernel_size_t);



#define __HAVE_ARCH_MEMMOVE

extern void *memmove(void *, const void *, __kernel_size_t);

extern void *__memmove(void *, const void *, __kernel_size_t);
@@ -56,6 +60,7 @@ void memcpy_flushcache(void *dst, const void *src, size_t cnt); 
 */



#define memcpy(dst, src, len) __memcpy(dst, src, len)

#define memcpy_mcs(dst, src, len) __memcpy_mcs(dst, src, len)

#define memmove(dst, src, len) __memmove(dst, src, len)

#define memset(s, c, n) __memset(s, c, n)

arch/arm64/include/asm/uaccess.h

+19 −0
Original line number Diff line number Diff line
@@ -432,4 +432,23 @@ static inline int __copy_from_user_flushcache(void *dst, const void __user *src, 
}

#endif



#ifdef CONFIG_ARCH_HAS_COPY_MC

/**

 * copy_mc_to_kernel - memory copy that handles source exceptions

 *

 * @dst:	destination address

 * @src:	source address

 * @len:	number of bytes to copy

 *

 * Return 0 for success, or number of bytes not copied if there was an

 * exception.

 */

static inline unsigned long __must_check

copy_mc_to_kernel(void *to, const void *from, unsigned long size)

{

	return (unsigned long)memcpy_mcs(to, from, size);

}

#define copy_mc_to_kernel copy_mc_to_kernel

#endif



#endif /* __ASM_UACCESS_H */

arch/arm64/lib/Makefile

+4 −4
Original line number Diff line number Diff line 
# SPDX-License-Identifier: GPL-2.0

lib-y		:= clear_user.o delay.o copy_from_user.o			\

		   copy_to_user.o copy_in_user.o copy_page.o			\

		   clear_page.o csum.o memchr.o memcpy.o memmove.o	\

		   clear_page.o csum.o memchr.o memcpy.o memcpy_mc.o memmove.o	\

		   memset.o memcmp.o strcmp.o strncmp.o strlen.o		\

		   strnlen.o strchr.o strrchr.o tishift.o

arch/arm64/lib/memcpy_mc.S

0 → 100644
+73 −0
Original line number Diff line number Diff line 
/* SPDX-License-Identifier: GPL-2.0-only */

/*

 * Copyright (C) 2013 ARM Ltd.

 * Copyright (C) 2013 Linaro.

 *

 * This code is based on glibc cortex strings work originally authored by Linaro

 * be found @

 *

 * http://bazaar.launchpad.net/~linaro-toolchain-dev/cortex-strings/trunk/

 * files/head:/src/aarch64/

 */



#include <linux/linkage.h>

#include <asm/assembler.h>

#include <asm/cache.h>



/*

 * Copy a buffer from src to dest (alignment handled by the hardware)

 * with machine check safe.

 *

 * Parameters:

 *	x0 - dest

 *	x1 - src

 *	x2 - n

 * Returns:

 *	x0 - bytes not copied

 */

	.macro ldrb1 reg, ptr, val

	CPY_MC(9998f, ldrb  \reg, [\ptr], \val)

	.endm



	.macro strb1 reg, ptr, val

	CPY_MC(9998f, strb \reg, [\ptr], \val)

	.endm



	.macro ldrh1 reg, ptr, val

	CPY_MC(9998f, ldrh  \reg, [\ptr], \val)

	.endm



	.macro strh1 reg, ptr, val

	CPY_MC(9998f, strh \reg, [\ptr], \val)

	.endm



	.macro ldr1 reg, ptr, val

	CPY_MC(9998f, ldr \reg, [\ptr], \val)

	.endm



	.macro str1 reg, ptr, val

	CPY_MC(9998f, str \reg, [\ptr], \val)

	.endm



	.macro ldp1 reg1, reg2, ptr, val

	CPY_MC(9998f, ldp \reg1, \reg2, [\ptr], \val)

	.endm



	.macro stp1 reg1, reg2, ptr, val

	CPY_MC(9998f, stp \reg1, \reg2, [\ptr], \val)

	.endm



end	.req	x5

SYM_FUNC_START_ALIAS(__memcpy_mcs)

SYM_FUNC_START_WEAK_PI(memcpy_mcs)

	add end, x0, x2

#include "copy_template.S"

	mov x0, #0

	ret



9998:	sub x0, end, dst

	ret

SYM_FUNC_END_PI(memcpy_mcs)

EXPORT_SYMBOL(memcpy_mcs)

SYM_FUNC_END_ALIAS(__memcpy_mcs)

EXPORT_SYMBOL(__memcpy_mcs)