[mirror_ubuntu-focal-kernel.git] / arch / x86 / include / asm / string_64.h

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _ASM_X86_STRING_64_H
#define _ASM_X86_STRING_64_H

#ifdef __KERNEL__
#include <linux/jump_label.h>

/* Written 2002 by Andi Kleen */

/* Only used for special circumstances. Stolen from i386/string.h */
static __always_inline void *__inline_memcpy(void *to, const void *from, size_t n)
{
	unsigned long d0, d1, d2;
	asm volatile("rep ; movsl\n\t"
		     "testb $2,%b4\n\t"
		     "je 1f\n\t"
		     "movsw\n"
		     "1:\ttestb $1,%b4\n\t"
		     "je 2f\n\t"
		     "movsb\n"
		     "2:"
		     : "=&c" (d0), "=&D" (d1), "=&S" (d2)
		     : "0" (n / 4), "q" (n), "1" ((long)to), "2" ((long)from)
		     : "memory");
	return to;
}

/* Even with __builtin_ the compiler may decide to use the out of line
   function. */

#define __HAVE_ARCH_MEMCPY 1
extern void *memcpy(void *to, const void *from, size_t len);
extern void *__memcpy(void *to, const void *from, size_t len);

#ifndef CONFIG_FORTIFY_SOURCE
#ifndef CONFIG_KMEMCHECK
#if (__GNUC__ == 4 && __GNUC_MINOR__ < 3) || __GNUC__ < 4
#define memcpy(dst, src, len)					\
({								\
	size_t __len = (len);					\
	void *__ret;						\
	if (__builtin_constant_p(len) && __len >= 64)		\
		__ret = __memcpy((dst), (src), __len);		\
	else							\
		__ret = __builtin_memcpy((dst), (src), __len);	\
	__ret;							\
})
#endif
#else
/*
 * kmemcheck becomes very happy if we use the REP instructions unconditionally,
 * because it means that we know both memory operands in advance.
 */
#define memcpy(dst, src, len) __inline_memcpy((dst), (src), (len))
#endif
#endif /* !CONFIG_FORTIFY_SOURCE */

#define __HAVE_ARCH_MEMSET
void *memset(void *s, int c, size_t n);
void *__memset(void *s, int c, size_t n);

#define __HAVE_ARCH_MEMSET16
static inline void *memset16(uint16_t *s, uint16_t v, size_t n)
{
	long d0, d1;
	asm volatile("rep\n\t"
		     "stosw"
		     : "=&c" (d0), "=&D" (d1)
		     : "a" (v), "1" (s), "0" (n)
		     : "memory");
	return s;
}

#define __HAVE_ARCH_MEMSET32
static inline void *memset32(uint32_t *s, uint32_t v, size_t n)
{
	long d0, d1;
	asm volatile("rep\n\t"
		     "stosl"
		     : "=&c" (d0), "=&D" (d1)
		     : "a" (v), "1" (s), "0" (n)
		     : "memory");
	return s;
}

#define __HAVE_ARCH_MEMSET64
static inline void *memset64(uint64_t *s, uint64_t v, size_t n)
{
	long d0, d1;
	asm volatile("rep\n\t"
		     "stosq"
		     : "=&c" (d0), "=&D" (d1)
		     : "a" (v), "1" (s), "0" (n)
		     : "memory");
	return s;
}

#define __HAVE_ARCH_MEMMOVE
void *memmove(void *dest, const void *src, size_t count);
void *__memmove(void *dest, const void *src, size_t count);

int memcmp(const void *cs, const void *ct, size_t count);
size_t strlen(const char *s);
char *strcpy(char *dest, const char *src);
char *strcat(char *dest, const char *src);
int strcmp(const char *cs, const char *ct);

#if defined(CONFIG_KASAN) && !defined(__SANITIZE_ADDRESS__)

/*
 * For files that not instrumented (e.g. mm/slub.c) we
 * should use not instrumented version of mem* functions.
 */

#undef memcpy
#define memcpy(dst, src, len) __memcpy(dst, src, len)
#define memmove(dst, src, len) __memmove(dst, src, len)
#define memset(s, c, n) __memset(s, c, n)

#ifndef __NO_FORTIFY
#define __NO_FORTIFY /* FORTIFY_SOURCE uses __builtin_memcpy, etc. */
#endif

#endif

#define __HAVE_ARCH_MEMCPY_MCSAFE 1
__must_check int memcpy_mcsafe_unrolled(void *dst, const void *src, size_t cnt);
DECLARE_STATIC_KEY_FALSE(mcsafe_key);

/**
 * memcpy_mcsafe - copy memory with indication if a machine check happened
 *
 * @dst:	destination address
 * @src:	source address
 * @cnt:	number of bytes to copy
 *
 * Low level memory copy function that catches machine checks
 * We only call into the "safe" function on systems that can
 * actually do machine check recovery. Everyone else can just
 * use memcpy().
 *
 * Return 0 for success, -EFAULT for fail
 */
static __always_inline __must_check int
memcpy_mcsafe(void *dst, const void *src, size_t cnt)
{
#ifdef CONFIG_X86_MCE
	if (static_branch_unlikely(&mcsafe_key))
		return memcpy_mcsafe_unrolled(dst, src, cnt);
	else
#endif
		memcpy(dst, src, cnt);
	return 0;
}

#ifdef CONFIG_ARCH_HAS_UACCESS_FLUSHCACHE
#define __HAVE_ARCH_MEMCPY_FLUSHCACHE 1
void memcpy_flushcache(void *dst, const void *src, size_t cnt);
#endif

#endif /* __KERNEL__ */

#endif /* _ASM_X86_STRING_64_H */
Commit	Line	Data
b2441318	1	/* SPDX-License-Identifier: GPL-2.0 */
1965aae3 PA	2	#ifndef _ASM_X86_STRING_64_H
1965aae3 PA	3	#define _ASM_X86_STRING_64_H
1da177e4 LT	4
1da177e4 LT	5	#ifdef __KERNEL__
3637efb0	6	#include <linux/jump_label.h>
1da177e4	7
953b2f1e	8	/* Written 2002 by Andi Kleen */
1da177e4	9
953b2f1e JP	10	/* Only used for special circumstances. Stolen from i386/string.h */
953b2f1e JP	11	static __always_inline void __inline_memcpy(void to, const void *from, size_t n)
1da177e4	12	{
953b2f1e JP	13	unsigned long d0, d1, d2;
	14	asm volatile("rep ; movsl\n\t"
	15	"testb $2,%b4\n\t"
	16	"je 1f\n\t"
	17	"movsw\n"
	18	"1:\ttestb $1,%b4\n\t"
	19	"je 2f\n\t"
	20	"movsb\n"
	21	"2:"
	22	: "=&c" (d0), "=&D" (d1), "=&S" (d2)
	23	: "0" (n / 4), "q" (n), "1" ((long)to), "2" ((long)from)
	24	: "memory");
	25	return to;
1da177e4 LT	26	}
	27
	28	/* Even with __builtin_ the compiler may decide to use the out of line
	29	function. */
	30
	31	#define __HAVE_ARCH_MEMCPY 1
a75ca545	32	extern void memcpy(void to, const void *from, size_t len);
393f203f AR	33	extern void __memcpy(void to, const void *from, size_t len);
393f203f AR	34
6974f0c4	35	#ifndef CONFIG_FORTIFY_SOURCE
f8561296	36	#ifndef CONFIG_KMEMCHECK
a75ca545	37	#if (__GNUC__ == 4 && __GNUC_MINOR__ < 3) \|\| __GNUC__ < 4
953b2f1e JP	38	#define memcpy(dst, src, len) \
	39	({ \
	40	size_t __len = (len); \
	41	void *__ret; \
	42	if (__builtin_constant_p(len) && __len >= 64) \
	43	__ret = __memcpy((dst), (src), __len); \
	44	else \
	45	__ret = __builtin_memcpy((dst), (src), __len); \
	46	__ret; \
	47	})
aac57f81	48	#endif
f8561296 VN	49	#else
	50	/*
	51	* kmemcheck becomes very happy if we use the REP instructions unconditionally,
	52	* because it means that we know both memory operands in advance.
	53	*/
	54	#define memcpy(dst, src, len) __inline_memcpy((dst), (src), (len))
	55	#endif
6974f0c4	56	#endif /* !CONFIG_FORTIFY_SOURCE */
1da177e4 LT	57
1da177e4 LT	58	#define __HAVE_ARCH_MEMSET
6edfba1b	59	void memset(void s, int c, size_t n);
393f203f	60	void __memset(void s, int c, size_t n);
1da177e4	61
4c512485 MW	62	#define __HAVE_ARCH_MEMSET16
	63	static inline void memset16(uint16_t s, uint16_t v, size_t n)
	64	{
	65	long d0, d1;
	66	asm volatile("rep\n\t"
	67	"stosw"
	68	: "=&c" (d0), "=&D" (d1)
	69	: "a" (v), "1" (s), "0" (n)
	70	: "memory");
	71	return s;
	72	}
	73
	74	#define __HAVE_ARCH_MEMSET32
	75	static inline void memset32(uint32_t s, uint32_t v, size_t n)
	76	{
	77	long d0, d1;
	78	asm volatile("rep\n\t"
	79	"stosl"
	80	: "=&c" (d0), "=&D" (d1)
	81	: "a" (v), "1" (s), "0" (n)
	82	: "memory");
	83	return s;
	84	}
	85
	86	#define __HAVE_ARCH_MEMSET64
	87	static inline void memset64(uint64_t s, uint64_t v, size_t n)
	88	{
	89	long d0, d1;
	90	asm volatile("rep\n\t"
	91	"stosq"
	92	: "=&c" (d0), "=&D" (d1)
	93	: "a" (v), "1" (s), "0" (n)
	94	: "memory");
	95	return s;
	96	}
	97
1da177e4	98	#define __HAVE_ARCH_MEMMOVE
953b2f1e	99	void memmove(void dest, const void *src, size_t count);
393f203f	100	void __memmove(void dest, const void *src, size_t count);
1da177e4	101
953b2f1e JP	102	int memcmp(const void cs, const void ct, size_t count);
	103	size_t strlen(const char *s);
	104	char strcpy(char dest, const char *src);
	105	char strcat(char dest, const char *src);
	106	int strcmp(const char cs, const char ct);
1da177e4	107
393f203f AR	108	#if defined(CONFIG_KASAN) && !defined(__SANITIZE_ADDRESS__)
	109
	110	/*
	111	* For files that not instrumented (e.g. mm/slub.c) we
	112	* should use not instrumented version of mem* functions.
	113	*/
	114
	115	#undef memcpy
	116	#define memcpy(dst, src, len) __memcpy(dst, src, len)
	117	#define memmove(dst, src, len) __memmove(dst, src, len)
	118	#define memset(s, c, n) __memset(s, c, n)
6974f0c4 DM	119
	120	#ifndef __NO_FORTIFY
	121	#define __NO_FORTIFY /* FORTIFY_SOURCE uses __builtin_memcpy, etc. */
	122	#endif
	123
393f203f AR	124	#endif
393f203f AR	125
6abccd1b	126	#define __HAVE_ARCH_MEMCPY_MCSAFE 1
9a6fb28a	127	__must_check int memcpy_mcsafe_unrolled(void dst, const void src, size_t cnt);
3637efb0 TL	128	DECLARE_STATIC_KEY_FALSE(mcsafe_key);
3637efb0 TL	129
92b0729c TL	130	/**
	131	* memcpy_mcsafe - copy memory with indication if a machine check happened
	132	*
	133	* @dst: destination address
	134	* @src: source address
	135	* @cnt: number of bytes to copy
	136	*
	137	* Low level memory copy function that catches machine checks
9a6fb28a TL	138	* We only call into the "safe" function on systems that can
	139	* actually do machine check recovery. Everyone else can just
	140	* use memcpy().
92b0729c	141	*
cbf8b5a2	142	* Return 0 for success, -EFAULT for fail
92b0729c	143	*/
9a6fb28a TL	144	static __always_inline __must_check int
	145	memcpy_mcsafe(void dst, const void src, size_t cnt)
	146	{
	147	#ifdef CONFIG_X86_MCE
	148	if (static_branch_unlikely(&mcsafe_key))
	149	return memcpy_mcsafe_unrolled(dst, src, cnt);
	150	else
	151	#endif
	152	memcpy(dst, src, cnt);
	153	return 0;
	154	}
92b0729c	155
0aed55af DW	156	#ifdef CONFIG_ARCH_HAS_UACCESS_FLUSHCACHE
	157	#define __HAVE_ARCH_MEMCPY_FLUSHCACHE 1
	158	void memcpy_flushcache(void dst, const void src, size_t cnt);
	159	#endif
	160
1da177e4 LT	161	#endif /* __KERNEL__ */
1da177e4 LT	162
1965aae3	163	#endif /* _ASM_X86_STRING_64_H */