xref: /linux/arch/x86/include/asm/string_64.h (revision e7d759f31ca295d589f7420719c311870bb3166f)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _ASM_X86_STRING_64_H
3 #define _ASM_X86_STRING_64_H
4 
5 #ifdef __KERNEL__
6 #include <linux/jump_label.h>
7 
8 /* Written 2002 by Andi Kleen */
9 
10 /* Even with __builtin_ the compiler may decide to use the out of line
11    function. */
12 
13 #if defined(__SANITIZE_MEMORY__) && defined(__NO_FORTIFY)
14 #include <linux/kmsan_string.h>
15 #endif
16 
17 #define __HAVE_ARCH_MEMCPY 1
18 extern void *memcpy(void *to, const void *from, size_t len);
19 extern void *__memcpy(void *to, const void *from, size_t len);
20 
21 #define __HAVE_ARCH_MEMSET
22 void *memset(void *s, int c, size_t n);
23 void *__memset(void *s, int c, size_t n);
24 
25 /*
26  * KMSAN needs to instrument as much code as possible. Use C versions of
27  * memsetXX() from lib/string.c under KMSAN.
28  */
29 #if !defined(CONFIG_KMSAN)
30 #define __HAVE_ARCH_MEMSET16
31 static inline void *memset16(uint16_t *s, uint16_t v, size_t n)
32 {
33 	long d0, d1;
34 	asm volatile("rep\n\t"
35 		     "stosw"
36 		     : "=&c" (d0), "=&D" (d1)
37 		     : "a" (v), "1" (s), "0" (n)
38 		     : "memory");
39 	return s;
40 }
41 
42 #define __HAVE_ARCH_MEMSET32
43 static inline void *memset32(uint32_t *s, uint32_t v, size_t n)
44 {
45 	long d0, d1;
46 	asm volatile("rep\n\t"
47 		     "stosl"
48 		     : "=&c" (d0), "=&D" (d1)
49 		     : "a" (v), "1" (s), "0" (n)
50 		     : "memory");
51 	return s;
52 }
53 
54 #define __HAVE_ARCH_MEMSET64
55 static inline void *memset64(uint64_t *s, uint64_t v, size_t n)
56 {
57 	long d0, d1;
58 	asm volatile("rep\n\t"
59 		     "stosq"
60 		     : "=&c" (d0), "=&D" (d1)
61 		     : "a" (v), "1" (s), "0" (n)
62 		     : "memory");
63 	return s;
64 }
65 #endif
66 
67 #define __HAVE_ARCH_MEMMOVE
68 void *memmove(void *dest, const void *src, size_t count);
69 void *__memmove(void *dest, const void *src, size_t count);
70 
71 int memcmp(const void *cs, const void *ct, size_t count);
72 size_t strlen(const char *s);
73 char *strcpy(char *dest, const char *src);
74 char *strcat(char *dest, const char *src);
75 int strcmp(const char *cs, const char *ct);
76 
77 #ifdef CONFIG_ARCH_HAS_UACCESS_FLUSHCACHE
78 #define __HAVE_ARCH_MEMCPY_FLUSHCACHE 1
79 void __memcpy_flushcache(void *dst, const void *src, size_t cnt);
80 static __always_inline void memcpy_flushcache(void *dst, const void *src, size_t cnt)
81 {
82 	if (__builtin_constant_p(cnt)) {
83 		switch (cnt) {
84 			case 4:
85 				asm ("movntil %1, %0" : "=m"(*(u32 *)dst) : "r"(*(u32 *)src));
86 				return;
87 			case 8:
88 				asm ("movntiq %1, %0" : "=m"(*(u64 *)dst) : "r"(*(u64 *)src));
89 				return;
90 			case 16:
91 				asm ("movntiq %1, %0" : "=m"(*(u64 *)dst) : "r"(*(u64 *)src));
92 				asm ("movntiq %1, %0" : "=m"(*(u64 *)(dst + 8)) : "r"(*(u64 *)(src + 8)));
93 				return;
94 		}
95 	}
96 	__memcpy_flushcache(dst, src, cnt);
97 }
98 #endif
99 
100 #endif /* __KERNEL__ */
101 
102 #endif /* _ASM_X86_STRING_64_H */
103