Commit | Line | Data |
---|---|---|
1965aae3 PA |
1 | #ifndef _ASM_X86_UACCESS_64_H |
2 | #define _ASM_X86_UACCESS_64_H | |
1da177e4 LT |
3 | |
4 | /* | |
5 | * User space memory access functions | |
6 | */ | |
1da177e4 LT |
7 | #include <linux/compiler.h> |
8 | #include <linux/errno.h> | |
16dbc6c9 | 9 | #include <linux/lockdep.h> |
1b1d9258 | 10 | #include <asm/alternative.h> |
cd4d09ec | 11 | #include <asm/cpufeatures.h> |
1da177e4 LT |
12 | #include <asm/page.h> |
13 | ||
1da177e4 LT |
14 | /* |
15 | * Copy To/From Userspace | |
16 | */ | |
17 | ||
18 | /* Handles exceptions in both to and from, but doesn't do access_ok */ | |
95912008 | 19 | __must_check unsigned long |
954e482b FY |
20 | copy_user_enhanced_fast_string(void *to, const void *from, unsigned len); |
21 | __must_check unsigned long | |
1b1d9258 JB |
22 | copy_user_generic_string(void *to, const void *from, unsigned len); |
23 | __must_check unsigned long | |
24 | copy_user_generic_unrolled(void *to, const void *from, unsigned len); | |
25 | ||
26 | static __always_inline __must_check unsigned long | |
27 | copy_user_generic(void *to, const void *from, unsigned len) | |
28 | { | |
29 | unsigned ret; | |
30 | ||
954e482b FY |
31 | /* |
32 | * If CPU has ERMS feature, use copy_user_enhanced_fast_string. | |
33 | * Otherwise, if CPU has rep_good feature, use copy_user_generic_string. | |
34 | * Otherwise, use copy_user_generic_unrolled. | |
35 | */ | |
36 | alternative_call_2(copy_user_generic_unrolled, | |
1b1d9258 JB |
37 | copy_user_generic_string, |
38 | X86_FEATURE_REP_GOOD, | |
954e482b FY |
39 | copy_user_enhanced_fast_string, |
40 | X86_FEATURE_ERMS, | |
1b1d9258 JB |
41 | ASM_OUTPUT2("=a" (ret), "=D" (to), "=S" (from), |
42 | "=d" (len)), | |
43 | "1" (to), "2" (from), "3" (len) | |
44 | : "memory", "rcx", "r8", "r9", "r10", "r11"); | |
45 | return ret; | |
46 | } | |
95912008 | 47 | |
95912008 | 48 | __must_check unsigned long |
95912008 AK |
49 | copy_in_user(void __user *to, const void __user *from, unsigned len); |
50 | ||
51 | static __always_inline __must_check | |
ff47ab4f | 52 | int __copy_from_user_nocheck(void *dst, const void __user *src, unsigned size) |
b896313e | 53 | { |
383d079b | 54 | int ret = 0; |
c10d38dd | 55 | |
1da177e4 | 56 | if (!__builtin_constant_p(size)) |
b896313e JP |
57 | return copy_user_generic(dst, (__force void *)src, size); |
58 | switch (size) { | |
11f1a4b9 LT |
59 | case 1: |
60 | __uaccess_begin(); | |
61 | __get_user_asm(*(u8 *)dst, (u8 __user *)src, | |
b896313e | 62 | ret, "b", "b", "=q", 1); |
11f1a4b9 | 63 | __uaccess_end(); |
1da177e4 | 64 | return ret; |
11f1a4b9 LT |
65 | case 2: |
66 | __uaccess_begin(); | |
67 | __get_user_asm(*(u16 *)dst, (u16 __user *)src, | |
b896313e | 68 | ret, "w", "w", "=r", 2); |
11f1a4b9 | 69 | __uaccess_end(); |
1da177e4 | 70 | return ret; |
11f1a4b9 LT |
71 | case 4: |
72 | __uaccess_begin(); | |
73 | __get_user_asm(*(u32 *)dst, (u32 __user *)src, | |
b896313e | 74 | ret, "l", "k", "=r", 4); |
11f1a4b9 | 75 | __uaccess_end(); |
b896313e | 76 | return ret; |
11f1a4b9 LT |
77 | case 8: |
78 | __uaccess_begin(); | |
79 | __get_user_asm(*(u64 *)dst, (u64 __user *)src, | |
b896313e | 80 | ret, "q", "", "=r", 8); |
11f1a4b9 | 81 | __uaccess_end(); |
1da177e4 | 82 | return ret; |
1da177e4 | 83 | case 10: |
11f1a4b9 | 84 | __uaccess_begin(); |
b896313e | 85 | __get_user_asm(*(u64 *)dst, (u64 __user *)src, |
20a4a236 | 86 | ret, "q", "", "=r", 10); |
11f1a4b9 LT |
87 | if (likely(!ret)) |
88 | __get_user_asm(*(u16 *)(8 + (char *)dst), | |
89 | (u16 __user *)(8 + (char __user *)src), | |
90 | ret, "w", "w", "=r", 2); | |
91 | __uaccess_end(); | |
b896313e | 92 | return ret; |
1da177e4 | 93 | case 16: |
11f1a4b9 | 94 | __uaccess_begin(); |
b896313e JP |
95 | __get_user_asm(*(u64 *)dst, (u64 __user *)src, |
96 | ret, "q", "", "=r", 16); | |
11f1a4b9 LT |
97 | if (likely(!ret)) |
98 | __get_user_asm(*(u64 *)(8 + (char *)dst), | |
99 | (u64 __user *)(8 + (char __user *)src), | |
100 | ret, "q", "", "=r", 8); | |
101 | __uaccess_end(); | |
b896313e | 102 | return ret; |
1da177e4 | 103 | default: |
b896313e | 104 | return copy_user_generic(dst, (__force void *)src, size); |
1da177e4 | 105 | } |
b896313e | 106 | } |
1da177e4 | 107 | |
95912008 | 108 | static __always_inline __must_check |
ff47ab4f AK |
109 | int __copy_from_user(void *dst, const void __user *src, unsigned size) |
110 | { | |
111 | might_fault(); | |
112 | return __copy_from_user_nocheck(dst, src, size); | |
113 | } | |
114 | ||
115 | static __always_inline __must_check | |
116 | int __copy_to_user_nocheck(void __user *dst, const void *src, unsigned size) | |
b896313e | 117 | { |
383d079b | 118 | int ret = 0; |
c10d38dd | 119 | |
1da177e4 | 120 | if (!__builtin_constant_p(size)) |
b896313e JP |
121 | return copy_user_generic((__force void *)dst, src, size); |
122 | switch (size) { | |
11f1a4b9 LT |
123 | case 1: |
124 | __uaccess_begin(); | |
125 | __put_user_asm(*(u8 *)src, (u8 __user *)dst, | |
b896313e | 126 | ret, "b", "b", "iq", 1); |
11f1a4b9 | 127 | __uaccess_end(); |
1da177e4 | 128 | return ret; |
11f1a4b9 LT |
129 | case 2: |
130 | __uaccess_begin(); | |
131 | __put_user_asm(*(u16 *)src, (u16 __user *)dst, | |
b896313e | 132 | ret, "w", "w", "ir", 2); |
11f1a4b9 | 133 | __uaccess_end(); |
1da177e4 | 134 | return ret; |
11f1a4b9 LT |
135 | case 4: |
136 | __uaccess_begin(); | |
137 | __put_user_asm(*(u32 *)src, (u32 __user *)dst, | |
b896313e | 138 | ret, "l", "k", "ir", 4); |
11f1a4b9 | 139 | __uaccess_end(); |
b896313e | 140 | return ret; |
11f1a4b9 LT |
141 | case 8: |
142 | __uaccess_begin(); | |
143 | __put_user_asm(*(u64 *)src, (u64 __user *)dst, | |
155b7352 | 144 | ret, "q", "", "er", 8); |
11f1a4b9 | 145 | __uaccess_end(); |
1da177e4 | 146 | return ret; |
1da177e4 | 147 | case 10: |
11f1a4b9 | 148 | __uaccess_begin(); |
b896313e | 149 | __put_user_asm(*(u64 *)src, (u64 __user *)dst, |
155b7352 | 150 | ret, "q", "", "er", 10); |
11f1a4b9 LT |
151 | if (likely(!ret)) { |
152 | asm("":::"memory"); | |
153 | __put_user_asm(4[(u16 *)src], 4 + (u16 __user *)dst, | |
154 | ret, "w", "w", "ir", 2); | |
155 | } | |
156 | __uaccess_end(); | |
b896313e | 157 | return ret; |
1da177e4 | 158 | case 16: |
11f1a4b9 | 159 | __uaccess_begin(); |
b896313e | 160 | __put_user_asm(*(u64 *)src, (u64 __user *)dst, |
155b7352 | 161 | ret, "q", "", "er", 16); |
11f1a4b9 LT |
162 | if (likely(!ret)) { |
163 | asm("":::"memory"); | |
164 | __put_user_asm(1[(u64 *)src], 1 + (u64 __user *)dst, | |
165 | ret, "q", "", "er", 8); | |
166 | } | |
167 | __uaccess_end(); | |
b896313e | 168 | return ret; |
1da177e4 | 169 | default: |
b896313e | 170 | return copy_user_generic((__force void *)dst, src, size); |
1da177e4 | 171 | } |
b896313e | 172 | } |
1da177e4 | 173 | |
ff47ab4f AK |
174 | static __always_inline __must_check |
175 | int __copy_to_user(void __user *dst, const void *src, unsigned size) | |
176 | { | |
177 | might_fault(); | |
178 | return __copy_to_user_nocheck(dst, src, size); | |
179 | } | |
180 | ||
95912008 AK |
181 | static __always_inline __must_check |
182 | int __copy_in_user(void __user *dst, const void __user *src, unsigned size) | |
b896313e | 183 | { |
383d079b | 184 | int ret = 0; |
c10d38dd | 185 | |
3ee1afa3 | 186 | might_fault(); |
1da177e4 | 187 | if (!__builtin_constant_p(size)) |
b896313e JP |
188 | return copy_user_generic((__force void *)dst, |
189 | (__force void *)src, size); | |
190 | switch (size) { | |
191 | case 1: { | |
1da177e4 | 192 | u8 tmp; |
11f1a4b9 | 193 | __uaccess_begin(); |
b896313e JP |
194 | __get_user_asm(tmp, (u8 __user *)src, |
195 | ret, "b", "b", "=q", 1); | |
1da177e4 | 196 | if (likely(!ret)) |
b896313e JP |
197 | __put_user_asm(tmp, (u8 __user *)dst, |
198 | ret, "b", "b", "iq", 1); | |
11f1a4b9 | 199 | __uaccess_end(); |
1da177e4 LT |
200 | return ret; |
201 | } | |
b896313e | 202 | case 2: { |
1da177e4 | 203 | u16 tmp; |
11f1a4b9 | 204 | __uaccess_begin(); |
b896313e JP |
205 | __get_user_asm(tmp, (u16 __user *)src, |
206 | ret, "w", "w", "=r", 2); | |
1da177e4 | 207 | if (likely(!ret)) |
b896313e JP |
208 | __put_user_asm(tmp, (u16 __user *)dst, |
209 | ret, "w", "w", "ir", 2); | |
11f1a4b9 | 210 | __uaccess_end(); |
1da177e4 LT |
211 | return ret; |
212 | } | |
213 | ||
b896313e | 214 | case 4: { |
1da177e4 | 215 | u32 tmp; |
11f1a4b9 | 216 | __uaccess_begin(); |
b896313e JP |
217 | __get_user_asm(tmp, (u32 __user *)src, |
218 | ret, "l", "k", "=r", 4); | |
1da177e4 | 219 | if (likely(!ret)) |
b896313e JP |
220 | __put_user_asm(tmp, (u32 __user *)dst, |
221 | ret, "l", "k", "ir", 4); | |
11f1a4b9 | 222 | __uaccess_end(); |
1da177e4 LT |
223 | return ret; |
224 | } | |
b896313e | 225 | case 8: { |
1da177e4 | 226 | u64 tmp; |
11f1a4b9 | 227 | __uaccess_begin(); |
b896313e JP |
228 | __get_user_asm(tmp, (u64 __user *)src, |
229 | ret, "q", "", "=r", 8); | |
1da177e4 | 230 | if (likely(!ret)) |
b896313e | 231 | __put_user_asm(tmp, (u64 __user *)dst, |
155b7352 | 232 | ret, "q", "", "er", 8); |
11f1a4b9 | 233 | __uaccess_end(); |
1da177e4 LT |
234 | return ret; |
235 | } | |
236 | default: | |
b896313e JP |
237 | return copy_user_generic((__force void *)dst, |
238 | (__force void *)src, size); | |
1da177e4 | 239 | } |
b896313e | 240 | } |
1da177e4 | 241 | |
14722485 JB |
242 | static __must_check __always_inline int |
243 | __copy_from_user_inatomic(void *dst, const void __user *src, unsigned size) | |
244 | { | |
df90ca96 | 245 | return __copy_from_user_nocheck(dst, src, size); |
14722485 | 246 | } |
b885808e AK |
247 | |
248 | static __must_check __always_inline int | |
249 | __copy_to_user_inatomic(void __user *dst, const void *src, unsigned size) | |
250 | { | |
df90ca96 | 251 | return __copy_to_user_nocheck(dst, src, size); |
b885808e | 252 | } |
1da177e4 | 253 | |
b896313e JP |
254 | extern long __copy_user_nocache(void *dst, const void __user *src, |
255 | unsigned size, int zerorest); | |
0812a579 | 256 | |
f1800536 IM |
257 | static inline int |
258 | __copy_from_user_nocache(void *dst, const void __user *src, unsigned size) | |
0812a579 | 259 | { |
016be2e5 | 260 | might_fault(); |
f1800536 | 261 | return __copy_user_nocache(dst, src, size, 1); |
0812a579 AK |
262 | } |
263 | ||
f1800536 IM |
264 | static inline int |
265 | __copy_from_user_inatomic_nocache(void *dst, const void __user *src, | |
266 | unsigned size) | |
0812a579 | 267 | { |
f1800536 | 268 | return __copy_user_nocache(dst, src, size, 0); |
0812a579 AK |
269 | } |
270 | ||
1129585a | 271 | unsigned long |
cae2a173 | 272 | copy_user_handle_tail(char *to, char *from, unsigned len); |
1129585a | 273 | |
1965aae3 | 274 | #endif /* _ASM_X86_UACCESS_64_H */ |