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b2441318 | 1 | /* SPDX-License-Identifier: GPL-2.0 */ |
2df5e8bc SR |
2 | #ifndef _ARCH_POWERPC_UACCESS_H |
3 | #define _ARCH_POWERPC_UACCESS_H | |
4 | ||
24bfa6a9 | 5 | #include <asm/ppc_asm.h> |
2df5e8bc | 6 | #include <asm/processor.h> |
6bfd93c3 | 7 | #include <asm/page.h> |
527b5bae | 8 | #include <asm/extable.h> |
de78a9c4 | 9 | #include <asm/kup.h> |
2df5e8bc | 10 | |
2df5e8bc SR |
11 | /* |
12 | * The fs value determines whether argument validity checking should be | |
13 | * performed or not. If get_fs() == USER_DS, checking is performed, with | |
14 | * get_fs() == KERNEL_DS, checking is bypassed. | |
15 | * | |
16 | * For historical reasons, these macros are grossly misnamed. | |
17 | * | |
18 | * The fs/ds values are now the highest legal address in the "segment". | |
19 | * This simplifies the checking in the routines below. | |
20 | */ | |
21 | ||
22 | #define MAKE_MM_SEG(s) ((mm_segment_t) { (s) }) | |
23 | ||
5015b494 | 24 | #define KERNEL_DS MAKE_MM_SEG(~0UL) |
2df5e8bc | 25 | #ifdef __powerpc64__ |
5015b494 SR |
26 | /* We use TASK_SIZE_USER64 as TASK_SIZE is not constant */ |
27 | #define USER_DS MAKE_MM_SEG(TASK_SIZE_USER64 - 1) | |
2df5e8bc | 28 | #else |
2df5e8bc SR |
29 | #define USER_DS MAKE_MM_SEG(TASK_SIZE - 1) |
30 | #endif | |
31 | ||
ba0635fc | 32 | #define get_fs() (current->thread.addr_limit) |
3e378680 ME |
33 | |
34 | static inline void set_fs(mm_segment_t fs) | |
35 | { | |
36 | current->thread.addr_limit = fs; | |
37 | /* On user-mode return check addr_limit (fs) is correct */ | |
38 | set_thread_flag(TIF_FSCHECK); | |
39 | } | |
2df5e8bc SR |
40 | |
41 | #define segment_eq(a, b) ((a).seg == (b).seg) | |
42 | ||
1629372c PM |
43 | #define user_addr_max() (get_fs().seg) |
44 | ||
2df5e8bc SR |
45 | #ifdef __powerpc64__ |
46 | /* | |
5015b494 SR |
47 | * This check is sufficient because there is a large enough |
48 | * gap between user addresses and the kernel addresses | |
2df5e8bc SR |
49 | */ |
50 | #define __access_ok(addr, size, segment) \ | |
5015b494 | 51 | (((addr) <= (segment).seg) && ((size) <= (segment).seg)) |
2df5e8bc SR |
52 | |
53 | #else | |
54 | ||
ef85dffd MM |
55 | static inline int __access_ok(unsigned long addr, unsigned long size, |
56 | mm_segment_t seg) | |
57 | { | |
58 | if (addr > seg.seg) | |
59 | return 0; | |
60 | return (size == 0 || size - 1 <= seg.seg - addr); | |
61 | } | |
2df5e8bc SR |
62 | |
63 | #endif | |
64 | ||
96d4f267 | 65 | #define access_ok(addr, size) \ |
4caf4ebf | 66 | (__chk_user_ptr(addr), \ |
2df5e8bc SR |
67 | __access_ok((__force unsigned long)(addr), (size), get_fs())) |
68 | ||
2df5e8bc SR |
69 | /* |
70 | * These are the main single-value transfer routines. They automatically | |
71 | * use the right size if we just have the right pointer type. | |
72 | * | |
73 | * This gets kind of ugly. We want to return _two_ values in "get_user()" | |
74 | * and yet we don't want to do any pointers, because that is too much | |
75 | * of a performance impact. Thus we have a few rather ugly macros here, | |
76 | * and hide all the ugliness from the user. | |
77 | * | |
78 | * The "__xxx" versions of the user access functions are versions that | |
79 | * do not verify the address space, that must have been done previously | |
80 | * with a separate "access_ok()" call (this is used when we do multiple | |
81 | * accesses to the same area of user memory). | |
82 | * | |
83 | * As we use the same address space for kernel and user data on the | |
84 | * PowerPC, we can just do these as direct assignments. (Of course, the | |
85 | * exception handling means that it's no longer "just"...) | |
86 | * | |
2df5e8bc SR |
87 | */ |
88 | #define get_user(x, ptr) \ | |
89 | __get_user_check((x), (ptr), sizeof(*(ptr))) | |
90 | #define put_user(x, ptr) \ | |
91 | __put_user_check((__typeof__(*(ptr)))(x), (ptr), sizeof(*(ptr))) | |
92 | ||
93 | #define __get_user(x, ptr) \ | |
5cd62333 | 94 | __get_user_nocheck((x), (ptr), sizeof(*(ptr)), true) |
2df5e8bc | 95 | #define __put_user(x, ptr) \ |
5cd62333 CL |
96 | __put_user_nocheck((__typeof__(*(ptr)))(x), (ptr), sizeof(*(ptr)), true) |
97 | ||
98 | #define __get_user_allowed(x, ptr) \ | |
99 | __get_user_nocheck((x), (ptr), sizeof(*(ptr)), false) | |
100 | #define __put_user_allowed(x, ptr) \ | |
101 | __put_user_nocheck((__typeof__(*(ptr)))(x), (ptr), sizeof(*(ptr)), false) | |
e68c825b | 102 | |
e68c825b BH |
103 | #define __get_user_inatomic(x, ptr) \ |
104 | __get_user_nosleep((x), (ptr), sizeof(*(ptr))) | |
105 | #define __put_user_inatomic(x, ptr) \ | |
106 | __put_user_nosleep((__typeof__(*(ptr)))(x), (ptr), sizeof(*(ptr))) | |
107 | ||
2df5e8bc SR |
108 | extern long __put_user_bad(void); |
109 | ||
2df5e8bc SR |
110 | /* |
111 | * We don't tell gcc that we are accessing memory, but this is OK | |
112 | * because we do not write to any memory gcc knows about, so there | |
113 | * are no aliasing issues. | |
114 | */ | |
115 | #define __put_user_asm(x, addr, err, op) \ | |
116 | __asm__ __volatile__( \ | |
117 | "1: " op " %1,0(%2) # put_user\n" \ | |
118 | "2:\n" \ | |
119 | ".section .fixup,\"ax\"\n" \ | |
120 | "3: li %0,%3\n" \ | |
121 | " b 2b\n" \ | |
122 | ".previous\n" \ | |
24bfa6a9 | 123 | EX_TABLE(1b, 3b) \ |
2df5e8bc | 124 | : "=r" (err) \ |
551c3c04 | 125 | : "r" (x), "b" (addr), "i" (-EFAULT), "0" (err)) |
2df5e8bc | 126 | |
5015b494 SR |
127 | #ifdef __powerpc64__ |
128 | #define __put_user_asm2(x, ptr, retval) \ | |
129 | __put_user_asm(x, ptr, retval, "std") | |
130 | #else /* __powerpc64__ */ | |
2df5e8bc SR |
131 | #define __put_user_asm2(x, addr, err) \ |
132 | __asm__ __volatile__( \ | |
133 | "1: stw %1,0(%2)\n" \ | |
134 | "2: stw %1+1,4(%2)\n" \ | |
135 | "3:\n" \ | |
136 | ".section .fixup,\"ax\"\n" \ | |
137 | "4: li %0,%3\n" \ | |
138 | " b 3b\n" \ | |
139 | ".previous\n" \ | |
24bfa6a9 NP |
140 | EX_TABLE(1b, 4b) \ |
141 | EX_TABLE(2b, 4b) \ | |
2df5e8bc | 142 | : "=r" (err) \ |
551c3c04 | 143 | : "r" (x), "b" (addr), "i" (-EFAULT), "0" (err)) |
2df5e8bc SR |
144 | #endif /* __powerpc64__ */ |
145 | ||
5cd62333 | 146 | #define __put_user_size_allowed(x, ptr, size, retval) \ |
2df5e8bc SR |
147 | do { \ |
148 | retval = 0; \ | |
149 | switch (size) { \ | |
150 | case 1: __put_user_asm(x, ptr, retval, "stb"); break; \ | |
151 | case 2: __put_user_asm(x, ptr, retval, "sth"); break; \ | |
152 | case 4: __put_user_asm(x, ptr, retval, "stw"); break; \ | |
153 | case 8: __put_user_asm2(x, ptr, retval); break; \ | |
154 | default: __put_user_bad(); \ | |
155 | } \ | |
5cd62333 CL |
156 | } while (0) |
157 | ||
158 | #define __put_user_size(x, ptr, size, retval) \ | |
159 | do { \ | |
160 | allow_write_to_user(ptr, size); \ | |
161 | __put_user_size_allowed(x, ptr, size, retval); \ | |
de78a9c4 | 162 | prevent_write_to_user(ptr, size); \ |
2df5e8bc SR |
163 | } while (0) |
164 | ||
5cd62333 | 165 | #define __put_user_nocheck(x, ptr, size, do_allow) \ |
2df5e8bc SR |
166 | ({ \ |
167 | long __pu_err; \ | |
6bfd93c3 | 168 | __typeof__(*(ptr)) __user *__pu_addr = (ptr); \ |
d02f6b7d NP |
169 | __typeof__(*(ptr)) __pu_val = (x); \ |
170 | __typeof__(size) __pu_size = (size); \ | |
171 | \ | |
6bfd93c3 | 172 | if (!is_kernel_addr((unsigned long)__pu_addr)) \ |
1af1717d | 173 | might_fault(); \ |
d02f6b7d | 174 | __chk_user_ptr(__pu_addr); \ |
5cd62333 | 175 | if (do_allow) \ |
d02f6b7d | 176 | __put_user_size(__pu_val, __pu_addr, __pu_size, __pu_err); \ |
5cd62333 | 177 | else \ |
d02f6b7d NP |
178 | __put_user_size_allowed(__pu_val, __pu_addr, __pu_size, __pu_err); \ |
179 | \ | |
2df5e8bc SR |
180 | __pu_err; \ |
181 | }) | |
182 | ||
183 | #define __put_user_check(x, ptr, size) \ | |
184 | ({ \ | |
185 | long __pu_err = -EFAULT; \ | |
186 | __typeof__(*(ptr)) __user *__pu_addr = (ptr); \ | |
d02f6b7d NP |
187 | __typeof__(*(ptr)) __pu_val = (x); \ |
188 | __typeof__(size) __pu_size = (size); \ | |
189 | \ | |
1af1717d | 190 | might_fault(); \ |
d02f6b7d NP |
191 | if (access_ok(__pu_addr, __pu_size)) \ |
192 | __put_user_size(__pu_val, __pu_addr, __pu_size, __pu_err); \ | |
193 | \ | |
2df5e8bc SR |
194 | __pu_err; \ |
195 | }) | |
196 | ||
e68c825b BH |
197 | #define __put_user_nosleep(x, ptr, size) \ |
198 | ({ \ | |
199 | long __pu_err; \ | |
200 | __typeof__(*(ptr)) __user *__pu_addr = (ptr); \ | |
d02f6b7d NP |
201 | __typeof__(*(ptr)) __pu_val = (x); \ |
202 | __typeof__(size) __pu_size = (size); \ | |
203 | \ | |
204 | __chk_user_ptr(__pu_addr); \ | |
205 | __put_user_size(__pu_val, __pu_addr, __pu_size, __pu_err); \ | |
206 | \ | |
e68c825b BH |
207 | __pu_err; \ |
208 | }) | |
209 | ||
210 | ||
2df5e8bc SR |
211 | extern long __get_user_bad(void); |
212 | ||
5080332c MN |
213 | /* |
214 | * This does an atomic 128 byte aligned load from userspace. | |
215 | * Upto caller to do enable_kernel_vmx() before calling! | |
216 | */ | |
217 | #define __get_user_atomic_128_aligned(kaddr, uaddr, err) \ | |
218 | __asm__ __volatile__( \ | |
219 | "1: lvx 0,0,%1 # get user\n" \ | |
220 | " stvx 0,0,%2 # put kernel\n" \ | |
221 | "2:\n" \ | |
222 | ".section .fixup,\"ax\"\n" \ | |
223 | "3: li %0,%3\n" \ | |
224 | " b 2b\n" \ | |
225 | ".previous\n" \ | |
226 | EX_TABLE(1b, 3b) \ | |
227 | : "=r" (err) \ | |
228 | : "b" (uaddr), "b" (kaddr), "i" (-EFAULT), "0" (err)) | |
229 | ||
2df5e8bc SR |
230 | #define __get_user_asm(x, addr, err, op) \ |
231 | __asm__ __volatile__( \ | |
5015b494 | 232 | "1: "op" %1,0(%2) # get_user\n" \ |
2df5e8bc SR |
233 | "2:\n" \ |
234 | ".section .fixup,\"ax\"\n" \ | |
235 | "3: li %0,%3\n" \ | |
236 | " li %1,0\n" \ | |
237 | " b 2b\n" \ | |
238 | ".previous\n" \ | |
24bfa6a9 | 239 | EX_TABLE(1b, 3b) \ |
2df5e8bc | 240 | : "=r" (err), "=r" (x) \ |
551c3c04 | 241 | : "b" (addr), "i" (-EFAULT), "0" (err)) |
2df5e8bc | 242 | |
5015b494 SR |
243 | #ifdef __powerpc64__ |
244 | #define __get_user_asm2(x, addr, err) \ | |
245 | __get_user_asm(x, addr, err, "ld") | |
246 | #else /* __powerpc64__ */ | |
247 | #define __get_user_asm2(x, addr, err) \ | |
2df5e8bc SR |
248 | __asm__ __volatile__( \ |
249 | "1: lwz %1,0(%2)\n" \ | |
250 | "2: lwz %1+1,4(%2)\n" \ | |
251 | "3:\n" \ | |
252 | ".section .fixup,\"ax\"\n" \ | |
253 | "4: li %0,%3\n" \ | |
254 | " li %1,0\n" \ | |
255 | " li %1+1,0\n" \ | |
256 | " b 3b\n" \ | |
257 | ".previous\n" \ | |
24bfa6a9 NP |
258 | EX_TABLE(1b, 4b) \ |
259 | EX_TABLE(2b, 4b) \ | |
2df5e8bc | 260 | : "=r" (err), "=&r" (x) \ |
551c3c04 | 261 | : "b" (addr), "i" (-EFAULT), "0" (err)) |
2df5e8bc SR |
262 | #endif /* __powerpc64__ */ |
263 | ||
5cd62333 | 264 | #define __get_user_size_allowed(x, ptr, size, retval) \ |
2df5e8bc SR |
265 | do { \ |
266 | retval = 0; \ | |
267 | __chk_user_ptr(ptr); \ | |
5015b494 SR |
268 | if (size > sizeof(x)) \ |
269 | (x) = __get_user_bad(); \ | |
2df5e8bc SR |
270 | switch (size) { \ |
271 | case 1: __get_user_asm(x, ptr, retval, "lbz"); break; \ | |
272 | case 2: __get_user_asm(x, ptr, retval, "lhz"); break; \ | |
273 | case 4: __get_user_asm(x, ptr, retval, "lwz"); break; \ | |
274 | case 8: __get_user_asm2(x, ptr, retval); break; \ | |
275 | default: (x) = __get_user_bad(); \ | |
276 | } \ | |
5cd62333 CL |
277 | } while (0) |
278 | ||
279 | #define __get_user_size(x, ptr, size, retval) \ | |
280 | do { \ | |
281 | allow_read_from_user(ptr, size); \ | |
282 | __get_user_size_allowed(x, ptr, size, retval); \ | |
de78a9c4 | 283 | prevent_read_from_user(ptr, size); \ |
2df5e8bc SR |
284 | } while (0) |
285 | ||
f7a6947c ME |
286 | /* |
287 | * This is a type: either unsigned long, if the argument fits into | |
288 | * that type, or otherwise unsigned long long. | |
289 | */ | |
290 | #define __long_type(x) \ | |
291 | __typeof__(__builtin_choose_expr(sizeof(x) > sizeof(0UL), 0ULL, 0UL)) | |
292 | ||
5cd62333 | 293 | #define __get_user_nocheck(x, ptr, size, do_allow) \ |
2df5e8bc SR |
294 | ({ \ |
295 | long __gu_err; \ | |
f7a6947c | 296 | __long_type(*(ptr)) __gu_val; \ |
e00d93ac | 297 | __typeof__(*(ptr)) __user *__gu_addr = (ptr); \ |
d02f6b7d NP |
298 | __typeof__(size) __gu_size = (size); \ |
299 | \ | |
300 | __chk_user_ptr(__gu_addr); \ | |
6bfd93c3 | 301 | if (!is_kernel_addr((unsigned long)__gu_addr)) \ |
1af1717d | 302 | might_fault(); \ |
ddf35cf3 | 303 | barrier_nospec(); \ |
5cd62333 | 304 | if (do_allow) \ |
d02f6b7d | 305 | __get_user_size(__gu_val, __gu_addr, __gu_size, __gu_err); \ |
5cd62333 | 306 | else \ |
d02f6b7d | 307 | __get_user_size_allowed(__gu_val, __gu_addr, __gu_size, __gu_err); \ |
2df5e8bc | 308 | (x) = (__typeof__(*(ptr)))__gu_val; \ |
d02f6b7d | 309 | \ |
2df5e8bc SR |
310 | __gu_err; \ |
311 | }) | |
312 | ||
2df5e8bc SR |
313 | #define __get_user_check(x, ptr, size) \ |
314 | ({ \ | |
315 | long __gu_err = -EFAULT; \ | |
f7a6947c | 316 | __long_type(*(ptr)) __gu_val = 0; \ |
e00d93ac | 317 | __typeof__(*(ptr)) __user *__gu_addr = (ptr); \ |
d02f6b7d NP |
318 | __typeof__(size) __gu_size = (size); \ |
319 | \ | |
1af1717d | 320 | might_fault(); \ |
d02f6b7d | 321 | if (access_ok(__gu_addr, __gu_size)) { \ |
ddf35cf3 | 322 | barrier_nospec(); \ |
d02f6b7d | 323 | __get_user_size(__gu_val, __gu_addr, __gu_size, __gu_err); \ |
ddf35cf3 | 324 | } \ |
505e4283 | 325 | (x) = (__force __typeof__(*(ptr)))__gu_val; \ |
d02f6b7d | 326 | \ |
2df5e8bc SR |
327 | __gu_err; \ |
328 | }) | |
329 | ||
e68c825b BH |
330 | #define __get_user_nosleep(x, ptr, size) \ |
331 | ({ \ | |
332 | long __gu_err; \ | |
f7a6947c | 333 | __long_type(*(ptr)) __gu_val; \ |
e00d93ac | 334 | __typeof__(*(ptr)) __user *__gu_addr = (ptr); \ |
d02f6b7d NP |
335 | __typeof__(size) __gu_size = (size); \ |
336 | \ | |
337 | __chk_user_ptr(__gu_addr); \ | |
ddf35cf3 | 338 | barrier_nospec(); \ |
d02f6b7d | 339 | __get_user_size(__gu_val, __gu_addr, __gu_size, __gu_err); \ |
505e4283 | 340 | (x) = (__force __typeof__(*(ptr)))__gu_val; \ |
d02f6b7d | 341 | \ |
e68c825b BH |
342 | __gu_err; \ |
343 | }) | |
344 | ||
345 | ||
2df5e8bc SR |
346 | /* more complex routines */ |
347 | ||
348 | extern unsigned long __copy_tofrom_user(void __user *to, | |
349 | const void __user *from, unsigned long size); | |
350 | ||
d6bd8194 | 351 | #ifdef __powerpc64__ |
3448890c AV |
352 | static inline unsigned long |
353 | raw_copy_in_user(void __user *to, const void __user *from, unsigned long n) | |
354 | { | |
de78a9c4 CL |
355 | unsigned long ret; |
356 | ||
6fbcdd59 | 357 | barrier_nospec(); |
1d8f739b | 358 | allow_read_write_user(to, from, n); |
de78a9c4 | 359 | ret = __copy_tofrom_user(to, from, n); |
1d8f739b | 360 | prevent_read_write_user(to, from, n); |
de78a9c4 | 361 | return ret; |
3448890c | 362 | } |
48fe4871 SR |
363 | #endif /* __powerpc64__ */ |
364 | ||
3448890c | 365 | static inline unsigned long raw_copy_from_user(void *to, |
5015b494 | 366 | const void __user *from, unsigned long n) |
2df5e8bc | 367 | { |
de78a9c4 | 368 | unsigned long ret; |
2df5e8bc | 369 | if (__builtin_constant_p(n) && (n <= 8)) { |
de78a9c4 | 370 | ret = 1; |
2df5e8bc SR |
371 | |
372 | switch (n) { | |
373 | case 1: | |
ddf35cf3 | 374 | barrier_nospec(); |
2df5e8bc SR |
375 | __get_user_size(*(u8 *)to, from, 1, ret); |
376 | break; | |
377 | case 2: | |
ddf35cf3 | 378 | barrier_nospec(); |
2df5e8bc SR |
379 | __get_user_size(*(u16 *)to, from, 2, ret); |
380 | break; | |
381 | case 4: | |
ddf35cf3 | 382 | barrier_nospec(); |
2df5e8bc SR |
383 | __get_user_size(*(u32 *)to, from, 4, ret); |
384 | break; | |
385 | case 8: | |
ddf35cf3 | 386 | barrier_nospec(); |
2df5e8bc SR |
387 | __get_user_size(*(u64 *)to, from, 8, ret); |
388 | break; | |
389 | } | |
48fe4871 SR |
390 | if (ret == 0) |
391 | return 0; | |
2df5e8bc | 392 | } |
1d3c1324 | 393 | |
ddf35cf3 | 394 | barrier_nospec(); |
de78a9c4 CL |
395 | allow_read_from_user(from, n); |
396 | ret = __copy_tofrom_user((__force void __user *)to, from, n); | |
397 | prevent_read_from_user(from, n); | |
398 | return ret; | |
2df5e8bc SR |
399 | } |
400 | ||
5cd62333 CL |
401 | static inline unsigned long |
402 | raw_copy_to_user_allowed(void __user *to, const void *from, unsigned long n) | |
2df5e8bc SR |
403 | { |
404 | if (__builtin_constant_p(n) && (n <= 8)) { | |
5cd62333 | 405 | unsigned long ret = 1; |
2df5e8bc SR |
406 | |
407 | switch (n) { | |
408 | case 1: | |
5cd62333 | 409 | __put_user_size_allowed(*(u8 *)from, (u8 __user *)to, 1, ret); |
2df5e8bc SR |
410 | break; |
411 | case 2: | |
5cd62333 | 412 | __put_user_size_allowed(*(u16 *)from, (u16 __user *)to, 2, ret); |
2df5e8bc SR |
413 | break; |
414 | case 4: | |
5cd62333 | 415 | __put_user_size_allowed(*(u32 *)from, (u32 __user *)to, 4, ret); |
2df5e8bc SR |
416 | break; |
417 | case 8: | |
5cd62333 | 418 | __put_user_size_allowed(*(u64 *)from, (u64 __user *)to, 8, ret); |
2df5e8bc SR |
419 | break; |
420 | } | |
48fe4871 SR |
421 | if (ret == 0) |
422 | return 0; | |
2df5e8bc | 423 | } |
81409e9e | 424 | |
5cd62333 CL |
425 | return __copy_tofrom_user(to, (__force const void __user *)from, n); |
426 | } | |
427 | ||
428 | static inline unsigned long | |
429 | raw_copy_to_user(void __user *to, const void *from, unsigned long n) | |
430 | { | |
431 | unsigned long ret; | |
432 | ||
de78a9c4 | 433 | allow_write_to_user(to, n); |
5cd62333 | 434 | ret = raw_copy_to_user_allowed(to, from, n); |
de78a9c4 CL |
435 | prevent_write_to_user(to, n); |
436 | return ret; | |
2df5e8bc SR |
437 | } |
438 | ||
42ac26d2 SS |
439 | static __always_inline unsigned long __must_check |
440 | copy_to_user_mcsafe(void __user *to, const void *from, unsigned long n) | |
441 | { | |
442 | if (likely(check_copy_size(from, n, true))) { | |
443 | if (access_ok(to, n)) { | |
444 | allow_write_to_user(to, n); | |
445 | n = memcpy_mcsafe((void *)to, from, n); | |
446 | prevent_write_to_user(to, n); | |
447 | } | |
448 | } | |
449 | ||
450 | return n; | |
451 | } | |
452 | ||
61e3acd8 | 453 | unsigned long __arch_clear_user(void __user *addr, unsigned long size); |
2df5e8bc SR |
454 | |
455 | static inline unsigned long clear_user(void __user *addr, unsigned long size) | |
456 | { | |
de78a9c4 | 457 | unsigned long ret = size; |
1af1717d | 458 | might_fault(); |
de78a9c4 CL |
459 | if (likely(access_ok(addr, size))) { |
460 | allow_write_to_user(addr, size); | |
61e3acd8 | 461 | ret = __arch_clear_user(addr, size); |
de78a9c4 CL |
462 | prevent_write_to_user(addr, size); |
463 | } | |
464 | return ret; | |
2df5e8bc SR |
465 | } |
466 | ||
61e3acd8 AD |
467 | static inline unsigned long __clear_user(void __user *addr, unsigned long size) |
468 | { | |
469 | return clear_user(addr, size); | |
470 | } | |
471 | ||
1629372c | 472 | extern long strncpy_from_user(char *dst, const char __user *src, long count); |
1629372c | 473 | extern __must_check long strnlen_user(const char __user *str, long n); |
2df5e8bc | 474 | |
6c44741d OH |
475 | extern long __copy_from_user_flushcache(void *dst, const void __user *src, |
476 | unsigned size); | |
477 | extern void memcpy_page_flushcache(char *to, struct page *page, size_t offset, | |
478 | size_t len); | |
479 | ||
5cd62333 CL |
480 | static __must_check inline bool user_access_begin(const void __user *ptr, size_t len) |
481 | { | |
482 | if (unlikely(!access_ok(ptr, len))) | |
483 | return false; | |
484 | allow_read_write_user((void __user *)ptr, ptr, len); | |
485 | return true; | |
486 | } | |
487 | #define user_access_begin user_access_begin | |
488 | #define user_access_end prevent_current_access_user | |
3d7dfd63 CL |
489 | #define user_access_save prevent_user_access_return |
490 | #define user_access_restore restore_user_access | |
5cd62333 CL |
491 | |
492 | #define unsafe_op_wrap(op, err) do { if (unlikely(op)) goto err; } while (0) | |
493 | #define unsafe_get_user(x, p, e) unsafe_op_wrap(__get_user_allowed(x, p), e) | |
494 | #define unsafe_put_user(x, p, e) unsafe_op_wrap(__put_user_allowed(x, p), e) | |
495 | #define unsafe_copy_to_user(d, s, l, e) \ | |
496 | unsafe_op_wrap(raw_copy_to_user_allowed(d, s, l), e) | |
497 | ||
2df5e8bc | 498 | #endif /* _ARCH_POWERPC_UACCESS_H */ |