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1965aae3 PA |
1 | #ifndef _ASM_X86_UACCESS_H |
2 | #define _ASM_X86_UACCESS_H | |
ca233862 GC |
3 | /* |
4 | * User space memory access functions | |
5 | */ | |
6 | #include <linux/errno.h> | |
7 | #include <linux/compiler.h> | |
8 | #include <linux/thread_info.h> | |
ca233862 GC |
9 | #include <linux/string.h> |
10 | #include <asm/asm.h> | |
11 | #include <asm/page.h> | |
63bcff2a | 12 | #include <asm/smap.h> |
ca233862 GC |
13 | |
14 | #define VERIFY_READ 0 | |
15 | #define VERIFY_WRITE 1 | |
16 | ||
17 | /* | |
18 | * The fs value determines whether argument validity checking should be | |
19 | * performed or not. If get_fs() == USER_DS, checking is performed, with | |
20 | * get_fs() == KERNEL_DS, checking is bypassed. | |
21 | * | |
22 | * For historical reasons, these macros are grossly misnamed. | |
23 | */ | |
24 | ||
25 | #define MAKE_MM_SEG(s) ((mm_segment_t) { (s) }) | |
26 | ||
27 | #define KERNEL_DS MAKE_MM_SEG(-1UL) | |
9063c61f | 28 | #define USER_DS MAKE_MM_SEG(TASK_SIZE_MAX) |
ca233862 GC |
29 | |
30 | #define get_ds() (KERNEL_DS) | |
31 | #define get_fs() (current_thread_info()->addr_limit) | |
32 | #define set_fs(x) (current_thread_info()->addr_limit = (x)) | |
33 | ||
34 | #define segment_eq(a, b) ((a).seg == (b).seg) | |
35 | ||
4ae73f2d | 36 | #define user_addr_max() (current_thread_info()->addr_limit.seg) |
bc6ca7b3 AS |
37 | #define __addr_ok(addr) \ |
38 | ((unsigned long __force)(addr) < user_addr_max()) | |
002ca169 | 39 | |
ca233862 GC |
40 | /* |
41 | * Test whether a block of memory is a valid user space address. | |
42 | * Returns 0 if the range is valid, nonzero otherwise. | |
43 | * | |
44 | * This is equivalent to the following test: | |
26afb7c6 | 45 | * (u33)addr + (u33)size > (u33)current->addr_limit.seg (u65 for x86_64) |
ca233862 GC |
46 | * |
47 | * This needs 33-bit (65-bit for x86_64) arithmetic. We have a carry... | |
48 | */ | |
49 | ||
bc6ca7b3 | 50 | #define __range_not_ok(addr, size, limit) \ |
ca233862 GC |
51 | ({ \ |
52 | unsigned long flag, roksum; \ | |
53 | __chk_user_ptr(addr); \ | |
54 | asm("add %3,%1 ; sbb %0,%0 ; cmp %1,%4 ; sbb $0,%0" \ | |
55 | : "=&r" (flag), "=r" (roksum) \ | |
56 | : "1" (addr), "g" ((long)(size)), \ | |
bc6ca7b3 | 57 | "rm" (limit)); \ |
ca233862 GC |
58 | flag; \ |
59 | }) | |
60 | ||
61 | /** | |
62 | * access_ok: - Checks if a user space pointer is valid | |
63 | * @type: Type of access: %VERIFY_READ or %VERIFY_WRITE. Note that | |
64 | * %VERIFY_WRITE is a superset of %VERIFY_READ - if it is safe | |
65 | * to write to a block, it is always safe to read from it. | |
66 | * @addr: User space pointer to start of block to check | |
67 | * @size: Size of block to check | |
68 | * | |
69 | * Context: User context only. This function may sleep. | |
70 | * | |
71 | * Checks if a pointer to a block of memory in user space is valid. | |
72 | * | |
73 | * Returns true (nonzero) if the memory block may be valid, false (zero) | |
74 | * if it is definitely invalid. | |
75 | * | |
76 | * Note that, depending on architecture, this function probably just | |
77 | * checks that the pointer is in the user space range - after calling | |
78 | * this function, memory access functions may still return -EFAULT. | |
79 | */ | |
bc6ca7b3 AS |
80 | #define access_ok(type, addr, size) \ |
81 | (likely(__range_not_ok(addr, size, user_addr_max()) == 0)) | |
ca233862 GC |
82 | |
83 | /* | |
70627654 PA |
84 | * The exception table consists of pairs of addresses relative to the |
85 | * exception table enty itself: the first is the address of an | |
86 | * instruction that is allowed to fault, and the second is the address | |
87 | * at which the program should continue. No registers are modified, | |
88 | * so it is entirely up to the continuation code to figure out what to | |
89 | * do. | |
ca233862 GC |
90 | * |
91 | * All the routines below use bits of fixup code that are out of line | |
92 | * with the main instruction path. This means when everything is well, | |
93 | * we don't even have to jump over them. Further, they do not intrude | |
94 | * on our cache or tlb entries. | |
95 | */ | |
96 | ||
97 | struct exception_table_entry { | |
70627654 | 98 | int insn, fixup; |
ca233862 | 99 | }; |
70627654 PA |
100 | /* This is not the generic standard exception_table_entry format */ |
101 | #define ARCH_HAS_SORT_EXTABLE | |
102 | #define ARCH_HAS_SEARCH_EXTABLE | |
ca233862 GC |
103 | |
104 | extern int fixup_exception(struct pt_regs *regs); | |
70627654 | 105 | extern int early_fixup_exception(unsigned long *ip); |
ca233862 GC |
106 | |
107 | /* | |
108 | * These are the main single-value transfer routines. They automatically | |
109 | * use the right size if we just have the right pointer type. | |
110 | * | |
111 | * This gets kind of ugly. We want to return _two_ values in "get_user()" | |
112 | * and yet we don't want to do any pointers, because that is too much | |
113 | * of a performance impact. Thus we have a few rather ugly macros here, | |
114 | * and hide all the ugliness from the user. | |
115 | * | |
116 | * The "__xxx" versions of the user access functions are versions that | |
117 | * do not verify the address space, that must have been done previously | |
118 | * with a separate "access_ok()" call (this is used when we do multiple | |
119 | * accesses to the same area of user memory). | |
120 | */ | |
121 | ||
122 | extern int __get_user_1(void); | |
123 | extern int __get_user_2(void); | |
124 | extern int __get_user_4(void); | |
125 | extern int __get_user_8(void); | |
126 | extern int __get_user_bad(void); | |
127 | ||
128 | #define __get_user_x(size, ret, x, ptr) \ | |
129 | asm volatile("call __get_user_" #size \ | |
4d5d7838 | 130 | : "=a" (ret), "=d" (x) \ |
ca233862 GC |
131 | : "0" (ptr)) \ |
132 | ||
865e5b76 GC |
133 | /* Careful: we have to cast the result to the type of the pointer |
134 | * for sign reasons */ | |
135 | ||
136 | /** | |
137 | * get_user: - Get a simple variable from user space. | |
138 | * @x: Variable to store result. | |
139 | * @ptr: Source address, in user space. | |
140 | * | |
141 | * Context: User context only. This function may sleep. | |
142 | * | |
143 | * This macro copies a single simple variable from user space to kernel | |
144 | * space. It supports simple types like char and int, but not larger | |
145 | * data types like structures or arrays. | |
146 | * | |
147 | * @ptr must have pointer-to-simple-variable type, and the result of | |
148 | * dereferencing @ptr must be assignable to @x without a cast. | |
149 | * | |
150 | * Returns zero on success, or -EFAULT on error. | |
151 | * On error, the variable @x is set to zero. | |
152 | */ | |
153 | #ifdef CONFIG_X86_32 | |
154 | #define __get_user_8(__ret_gu, __val_gu, ptr) \ | |
155 | __get_user_x(X, __ret_gu, __val_gu, ptr) | |
156 | #else | |
157 | #define __get_user_8(__ret_gu, __val_gu, ptr) \ | |
158 | __get_user_x(8, __ret_gu, __val_gu, ptr) | |
159 | #endif | |
160 | ||
161 | #define get_user(x, ptr) \ | |
162 | ({ \ | |
163 | int __ret_gu; \ | |
164 | unsigned long __val_gu; \ | |
165 | __chk_user_ptr(ptr); \ | |
3ee1afa3 | 166 | might_fault(); \ |
865e5b76 GC |
167 | switch (sizeof(*(ptr))) { \ |
168 | case 1: \ | |
169 | __get_user_x(1, __ret_gu, __val_gu, ptr); \ | |
170 | break; \ | |
171 | case 2: \ | |
172 | __get_user_x(2, __ret_gu, __val_gu, ptr); \ | |
173 | break; \ | |
174 | case 4: \ | |
175 | __get_user_x(4, __ret_gu, __val_gu, ptr); \ | |
176 | break; \ | |
177 | case 8: \ | |
178 | __get_user_8(__ret_gu, __val_gu, ptr); \ | |
179 | break; \ | |
180 | default: \ | |
181 | __get_user_x(X, __ret_gu, __val_gu, ptr); \ | |
182 | break; \ | |
183 | } \ | |
184 | (x) = (__typeof__(*(ptr)))__val_gu; \ | |
185 | __ret_gu; \ | |
186 | }) | |
187 | ||
e30a44fd GC |
188 | #define __put_user_x(size, x, ptr, __ret_pu) \ |
189 | asm volatile("call __put_user_" #size : "=a" (__ret_pu) \ | |
4d5d7838 | 190 | : "0" ((typeof(*(ptr)))(x)), "c" (ptr) : "ebx") |
e30a44fd GC |
191 | |
192 | ||
193 | ||
dc70ddf4 | 194 | #ifdef CONFIG_X86_32 |
18114f61 | 195 | #define __put_user_asm_u64(x, addr, err, errret) \ |
63bcff2a PA |
196 | asm volatile(ASM_STAC "\n" \ |
197 | "1: movl %%eax,0(%2)\n" \ | |
dc70ddf4 | 198 | "2: movl %%edx,4(%2)\n" \ |
63bcff2a | 199 | "3: " ASM_CLAC "\n" \ |
dc70ddf4 GC |
200 | ".section .fixup,\"ax\"\n" \ |
201 | "4: movl %3,%0\n" \ | |
202 | " jmp 3b\n" \ | |
203 | ".previous\n" \ | |
204 | _ASM_EXTABLE(1b, 4b) \ | |
205 | _ASM_EXTABLE(2b, 4b) \ | |
206 | : "=r" (err) \ | |
18114f61 | 207 | : "A" (x), "r" (addr), "i" (errret), "0" (err)) |
e30a44fd | 208 | |
fe40c0af | 209 | #define __put_user_asm_ex_u64(x, addr) \ |
63bcff2a PA |
210 | asm volatile(ASM_STAC "\n" \ |
211 | "1: movl %%eax,0(%1)\n" \ | |
fe40c0af | 212 | "2: movl %%edx,4(%1)\n" \ |
63bcff2a | 213 | "3: " ASM_CLAC "\n" \ |
535c0c34 PA |
214 | _ASM_EXTABLE_EX(1b, 2b) \ |
215 | _ASM_EXTABLE_EX(2b, 3b) \ | |
fe40c0af HS |
216 | : : "A" (x), "r" (addr)) |
217 | ||
e30a44fd GC |
218 | #define __put_user_x8(x, ptr, __ret_pu) \ |
219 | asm volatile("call __put_user_8" : "=a" (__ret_pu) \ | |
220 | : "A" ((typeof(*(ptr)))(x)), "c" (ptr) : "ebx") | |
dc70ddf4 | 221 | #else |
18114f61 | 222 | #define __put_user_asm_u64(x, ptr, retval, errret) \ |
ebe119cd | 223 | __put_user_asm(x, ptr, retval, "q", "", "er", errret) |
fe40c0af | 224 | #define __put_user_asm_ex_u64(x, addr) \ |
ebe119cd | 225 | __put_user_asm_ex(x, addr, "q", "", "er") |
e30a44fd | 226 | #define __put_user_x8(x, ptr, __ret_pu) __put_user_x(8, x, ptr, __ret_pu) |
dc70ddf4 GC |
227 | #endif |
228 | ||
e30a44fd GC |
229 | extern void __put_user_bad(void); |
230 | ||
231 | /* | |
232 | * Strange magic calling convention: pointer in %ecx, | |
233 | * value in %eax(:%edx), return value in %eax. clobbers %rbx | |
234 | */ | |
235 | extern void __put_user_1(void); | |
236 | extern void __put_user_2(void); | |
237 | extern void __put_user_4(void); | |
238 | extern void __put_user_8(void); | |
239 | ||
dc70ddf4 GC |
240 | #ifdef CONFIG_X86_WP_WORKS_OK |
241 | ||
e30a44fd GC |
242 | /** |
243 | * put_user: - Write a simple value into user space. | |
244 | * @x: Value to copy to user space. | |
245 | * @ptr: Destination address, in user space. | |
246 | * | |
247 | * Context: User context only. This function may sleep. | |
248 | * | |
249 | * This macro copies a single simple value from kernel space to user | |
250 | * space. It supports simple types like char and int, but not larger | |
251 | * data types like structures or arrays. | |
252 | * | |
253 | * @ptr must have pointer-to-simple-variable type, and @x must be assignable | |
254 | * to the result of dereferencing @ptr. | |
255 | * | |
256 | * Returns zero on success, or -EFAULT on error. | |
257 | */ | |
258 | #define put_user(x, ptr) \ | |
259 | ({ \ | |
260 | int __ret_pu; \ | |
261 | __typeof__(*(ptr)) __pu_val; \ | |
262 | __chk_user_ptr(ptr); \ | |
3ee1afa3 | 263 | might_fault(); \ |
e30a44fd GC |
264 | __pu_val = x; \ |
265 | switch (sizeof(*(ptr))) { \ | |
266 | case 1: \ | |
267 | __put_user_x(1, __pu_val, ptr, __ret_pu); \ | |
268 | break; \ | |
269 | case 2: \ | |
270 | __put_user_x(2, __pu_val, ptr, __ret_pu); \ | |
271 | break; \ | |
272 | case 4: \ | |
273 | __put_user_x(4, __pu_val, ptr, __ret_pu); \ | |
274 | break; \ | |
275 | case 8: \ | |
276 | __put_user_x8(__pu_val, ptr, __ret_pu); \ | |
277 | break; \ | |
278 | default: \ | |
279 | __put_user_x(X, __pu_val, ptr, __ret_pu); \ | |
280 | break; \ | |
281 | } \ | |
282 | __ret_pu; \ | |
283 | }) | |
284 | ||
dc70ddf4 GC |
285 | #define __put_user_size(x, ptr, size, retval, errret) \ |
286 | do { \ | |
287 | retval = 0; \ | |
288 | __chk_user_ptr(ptr); \ | |
289 | switch (size) { \ | |
290 | case 1: \ | |
291 | __put_user_asm(x, ptr, retval, "b", "b", "iq", errret); \ | |
292 | break; \ | |
293 | case 2: \ | |
294 | __put_user_asm(x, ptr, retval, "w", "w", "ir", errret); \ | |
295 | break; \ | |
296 | case 4: \ | |
4d5d7838 | 297 | __put_user_asm(x, ptr, retval, "l", "k", "ir", errret); \ |
dc70ddf4 GC |
298 | break; \ |
299 | case 8: \ | |
18114f61 HS |
300 | __put_user_asm_u64((__typeof__(*ptr))(x), ptr, retval, \ |
301 | errret); \ | |
dc70ddf4 GC |
302 | break; \ |
303 | default: \ | |
304 | __put_user_bad(); \ | |
305 | } \ | |
306 | } while (0) | |
307 | ||
fe40c0af HS |
308 | #define __put_user_size_ex(x, ptr, size) \ |
309 | do { \ | |
310 | __chk_user_ptr(ptr); \ | |
311 | switch (size) { \ | |
312 | case 1: \ | |
313 | __put_user_asm_ex(x, ptr, "b", "b", "iq"); \ | |
314 | break; \ | |
315 | case 2: \ | |
316 | __put_user_asm_ex(x, ptr, "w", "w", "ir"); \ | |
317 | break; \ | |
318 | case 4: \ | |
319 | __put_user_asm_ex(x, ptr, "l", "k", "ir"); \ | |
320 | break; \ | |
321 | case 8: \ | |
322 | __put_user_asm_ex_u64((__typeof__(*ptr))(x), ptr); \ | |
323 | break; \ | |
324 | default: \ | |
325 | __put_user_bad(); \ | |
326 | } \ | |
327 | } while (0) | |
328 | ||
dc70ddf4 GC |
329 | #else |
330 | ||
331 | #define __put_user_size(x, ptr, size, retval, errret) \ | |
332 | do { \ | |
333 | __typeof__(*(ptr))__pus_tmp = x; \ | |
334 | retval = 0; \ | |
335 | \ | |
336 | if (unlikely(__copy_to_user_ll(ptr, &__pus_tmp, size) != 0)) \ | |
337 | retval = errret; \ | |
338 | } while (0) | |
339 | ||
e30a44fd GC |
340 | #define put_user(x, ptr) \ |
341 | ({ \ | |
342 | int __ret_pu; \ | |
343 | __typeof__(*(ptr))__pus_tmp = x; \ | |
344 | __ret_pu = 0; \ | |
345 | if (unlikely(__copy_to_user_ll(ptr, &__pus_tmp, \ | |
346 | sizeof(*(ptr))) != 0)) \ | |
347 | __ret_pu = -EFAULT; \ | |
348 | __ret_pu; \ | |
349 | }) | |
dc70ddf4 GC |
350 | #endif |
351 | ||
3f168221 GC |
352 | #ifdef CONFIG_X86_32 |
353 | #define __get_user_asm_u64(x, ptr, retval, errret) (x) = __get_user_bad() | |
fe40c0af | 354 | #define __get_user_asm_ex_u64(x, ptr) (x) = __get_user_bad() |
3f168221 GC |
355 | #else |
356 | #define __get_user_asm_u64(x, ptr, retval, errret) \ | |
357 | __get_user_asm(x, ptr, retval, "q", "", "=r", errret) | |
fe40c0af HS |
358 | #define __get_user_asm_ex_u64(x, ptr) \ |
359 | __get_user_asm_ex(x, ptr, "q", "", "=r") | |
3f168221 GC |
360 | #endif |
361 | ||
362 | #define __get_user_size(x, ptr, size, retval, errret) \ | |
363 | do { \ | |
364 | retval = 0; \ | |
365 | __chk_user_ptr(ptr); \ | |
366 | switch (size) { \ | |
367 | case 1: \ | |
368 | __get_user_asm(x, ptr, retval, "b", "b", "=q", errret); \ | |
369 | break; \ | |
370 | case 2: \ | |
371 | __get_user_asm(x, ptr, retval, "w", "w", "=r", errret); \ | |
372 | break; \ | |
373 | case 4: \ | |
374 | __get_user_asm(x, ptr, retval, "l", "k", "=r", errret); \ | |
375 | break; \ | |
376 | case 8: \ | |
377 | __get_user_asm_u64(x, ptr, retval, errret); \ | |
378 | break; \ | |
379 | default: \ | |
380 | (x) = __get_user_bad(); \ | |
381 | } \ | |
382 | } while (0) | |
383 | ||
384 | #define __get_user_asm(x, addr, err, itype, rtype, ltype, errret) \ | |
63bcff2a PA |
385 | asm volatile(ASM_STAC "\n" \ |
386 | "1: mov"itype" %2,%"rtype"1\n" \ | |
387 | "2: " ASM_CLAC "\n" \ | |
3f168221 GC |
388 | ".section .fixup,\"ax\"\n" \ |
389 | "3: mov %3,%0\n" \ | |
390 | " xor"itype" %"rtype"1,%"rtype"1\n" \ | |
391 | " jmp 2b\n" \ | |
392 | ".previous\n" \ | |
393 | _ASM_EXTABLE(1b, 3b) \ | |
394 | : "=r" (err), ltype(x) \ | |
395 | : "m" (__m(addr)), "i" (errret), "0" (err)) | |
396 | ||
fe40c0af HS |
397 | #define __get_user_size_ex(x, ptr, size) \ |
398 | do { \ | |
399 | __chk_user_ptr(ptr); \ | |
400 | switch (size) { \ | |
401 | case 1: \ | |
402 | __get_user_asm_ex(x, ptr, "b", "b", "=q"); \ | |
403 | break; \ | |
404 | case 2: \ | |
405 | __get_user_asm_ex(x, ptr, "w", "w", "=r"); \ | |
406 | break; \ | |
407 | case 4: \ | |
408 | __get_user_asm_ex(x, ptr, "l", "k", "=r"); \ | |
409 | break; \ | |
410 | case 8: \ | |
411 | __get_user_asm_ex_u64(x, ptr); \ | |
412 | break; \ | |
413 | default: \ | |
414 | (x) = __get_user_bad(); \ | |
415 | } \ | |
416 | } while (0) | |
417 | ||
418 | #define __get_user_asm_ex(x, addr, itype, rtype, ltype) \ | |
5e88353d PA |
419 | asm volatile("1: mov"itype" %1,%"rtype"0\n" \ |
420 | "2:\n" \ | |
535c0c34 | 421 | _ASM_EXTABLE_EX(1b, 2b) \ |
fe40c0af HS |
422 | : ltype(x) : "m" (__m(addr))) |
423 | ||
dc70ddf4 GC |
424 | #define __put_user_nocheck(x, ptr, size) \ |
425 | ({ \ | |
16855f87 | 426 | int __pu_err; \ |
dc70ddf4 GC |
427 | __put_user_size((x), (ptr), (size), __pu_err, -EFAULT); \ |
428 | __pu_err; \ | |
429 | }) | |
430 | ||
3f168221 GC |
431 | #define __get_user_nocheck(x, ptr, size) \ |
432 | ({ \ | |
16855f87 | 433 | int __gu_err; \ |
3f168221 GC |
434 | unsigned long __gu_val; \ |
435 | __get_user_size(__gu_val, (ptr), (size), __gu_err, -EFAULT); \ | |
436 | (x) = (__force __typeof__(*(ptr)))__gu_val; \ | |
437 | __gu_err; \ | |
438 | }) | |
dc70ddf4 GC |
439 | |
440 | /* FIXME: this hack is definitely wrong -AK */ | |
441 | struct __large_struct { unsigned long buf[100]; }; | |
442 | #define __m(x) (*(struct __large_struct __user *)(x)) | |
443 | ||
444 | /* | |
445 | * Tell gcc we read from memory instead of writing: this is because | |
446 | * we do not write to any memory gcc knows about, so there are no | |
447 | * aliasing issues. | |
448 | */ | |
449 | #define __put_user_asm(x, addr, err, itype, rtype, ltype, errret) \ | |
63bcff2a PA |
450 | asm volatile(ASM_STAC "\n" \ |
451 | "1: mov"itype" %"rtype"1,%2\n" \ | |
452 | "2: " ASM_CLAC "\n" \ | |
dc70ddf4 GC |
453 | ".section .fixup,\"ax\"\n" \ |
454 | "3: mov %3,%0\n" \ | |
455 | " jmp 2b\n" \ | |
456 | ".previous\n" \ | |
457 | _ASM_EXTABLE(1b, 3b) \ | |
458 | : "=r"(err) \ | |
459 | : ltype(x), "m" (__m(addr)), "i" (errret), "0" (err)) | |
fe40c0af HS |
460 | |
461 | #define __put_user_asm_ex(x, addr, itype, rtype, ltype) \ | |
5e88353d PA |
462 | asm volatile("1: mov"itype" %"rtype"0,%1\n" \ |
463 | "2:\n" \ | |
535c0c34 | 464 | _ASM_EXTABLE_EX(1b, 2b) \ |
fe40c0af HS |
465 | : : ltype(x), "m" (__m(addr))) |
466 | ||
467 | /* | |
468 | * uaccess_try and catch | |
469 | */ | |
470 | #define uaccess_try do { \ | |
fe40c0af | 471 | current_thread_info()->uaccess_err = 0; \ |
5e88353d | 472 | stac(); \ |
fe40c0af HS |
473 | barrier(); |
474 | ||
475 | #define uaccess_catch(err) \ | |
5e88353d | 476 | clac(); \ |
4fc34901 | 477 | (err) |= (current_thread_info()->uaccess_err ? -EFAULT : 0); \ |
fe40c0af HS |
478 | } while (0) |
479 | ||
8cb834e9 GC |
480 | /** |
481 | * __get_user: - Get a simple variable from user space, with less checking. | |
482 | * @x: Variable to store result. | |
483 | * @ptr: Source address, in user space. | |
484 | * | |
485 | * Context: User context only. This function may sleep. | |
486 | * | |
487 | * This macro copies a single simple variable from user space to kernel | |
488 | * space. It supports simple types like char and int, but not larger | |
489 | * data types like structures or arrays. | |
490 | * | |
491 | * @ptr must have pointer-to-simple-variable type, and the result of | |
492 | * dereferencing @ptr must be assignable to @x without a cast. | |
493 | * | |
494 | * Caller must check the pointer with access_ok() before calling this | |
495 | * function. | |
496 | * | |
497 | * Returns zero on success, or -EFAULT on error. | |
498 | * On error, the variable @x is set to zero. | |
499 | */ | |
500 | ||
501 | #define __get_user(x, ptr) \ | |
502 | __get_user_nocheck((x), (ptr), sizeof(*(ptr))) | |
fe40c0af | 503 | |
8cb834e9 GC |
504 | /** |
505 | * __put_user: - Write a simple value into user space, with less checking. | |
506 | * @x: Value to copy to user space. | |
507 | * @ptr: Destination address, in user space. | |
508 | * | |
509 | * Context: User context only. This function may sleep. | |
510 | * | |
511 | * This macro copies a single simple value from kernel space to user | |
512 | * space. It supports simple types like char and int, but not larger | |
513 | * data types like structures or arrays. | |
514 | * | |
515 | * @ptr must have pointer-to-simple-variable type, and @x must be assignable | |
516 | * to the result of dereferencing @ptr. | |
517 | * | |
518 | * Caller must check the pointer with access_ok() before calling this | |
519 | * function. | |
520 | * | |
521 | * Returns zero on success, or -EFAULT on error. | |
522 | */ | |
523 | ||
524 | #define __put_user(x, ptr) \ | |
525 | __put_user_nocheck((__typeof__(*(ptr)))(x), (ptr), sizeof(*(ptr))) | |
dc70ddf4 | 526 | |
8cb834e9 GC |
527 | #define __get_user_unaligned __get_user |
528 | #define __put_user_unaligned __put_user | |
865e5b76 | 529 | |
fe40c0af HS |
530 | /* |
531 | * {get|put}_user_try and catch | |
532 | * | |
533 | * get_user_try { | |
534 | * get_user_ex(...); | |
535 | * } get_user_catch(err) | |
536 | */ | |
537 | #define get_user_try uaccess_try | |
538 | #define get_user_catch(err) uaccess_catch(err) | |
fe40c0af HS |
539 | |
540 | #define get_user_ex(x, ptr) do { \ | |
541 | unsigned long __gue_val; \ | |
542 | __get_user_size_ex((__gue_val), (ptr), (sizeof(*(ptr)))); \ | |
543 | (x) = (__force __typeof__(*(ptr)))__gue_val; \ | |
544 | } while (0) | |
545 | ||
019a1369 HS |
546 | #ifdef CONFIG_X86_WP_WORKS_OK |
547 | ||
548 | #define put_user_try uaccess_try | |
549 | #define put_user_catch(err) uaccess_catch(err) | |
550 | ||
fe40c0af HS |
551 | #define put_user_ex(x, ptr) \ |
552 | __put_user_size_ex((__typeof__(*(ptr)))(x), (ptr), sizeof(*(ptr))) | |
553 | ||
019a1369 HS |
554 | #else /* !CONFIG_X86_WP_WORKS_OK */ |
555 | ||
556 | #define put_user_try do { \ | |
557 | int __uaccess_err = 0; | |
558 | ||
559 | #define put_user_catch(err) \ | |
560 | (err) |= __uaccess_err; \ | |
561 | } while (0) | |
562 | ||
563 | #define put_user_ex(x, ptr) do { \ | |
564 | __uaccess_err |= __put_user(x, ptr); \ | |
565 | } while (0) | |
566 | ||
567 | #endif /* CONFIG_X86_WP_WORKS_OK */ | |
568 | ||
1ac2e6ca RR |
569 | extern unsigned long |
570 | copy_from_user_nmi(void *to, const void __user *from, unsigned long n); | |
92ae03f2 LT |
571 | extern __must_check long |
572 | strncpy_from_user(char *dst, const char __user *src, long count); | |
1ac2e6ca | 573 | |
5723aa99 LT |
574 | extern __must_check long strlen_user(const char __user *str); |
575 | extern __must_check long strnlen_user(const char __user *str, long n); | |
576 | ||
a052858f PA |
577 | unsigned long __must_check clear_user(void __user *mem, unsigned long len); |
578 | unsigned long __must_check __clear_user(void __user *mem, unsigned long len); | |
579 | ||
8bc7de0c GC |
580 | /* |
581 | * movsl can be slow when source and dest are not both 8-byte aligned | |
582 | */ | |
583 | #ifdef CONFIG_X86_INTEL_USERCOPY | |
584 | extern struct movsl_mask { | |
585 | int mask; | |
586 | } ____cacheline_aligned_in_smp movsl_mask; | |
587 | #endif | |
588 | ||
22cac167 GC |
589 | #define ARCH_HAS_NOCACHE_UACCESS 1 |
590 | ||
96a388de | 591 | #ifdef CONFIG_X86_32 |
a1ce3928 | 592 | # include <asm/uaccess_32.h> |
96a388de | 593 | #else |
a1ce3928 | 594 | # include <asm/uaccess_64.h> |
96a388de | 595 | #endif |
ca233862 | 596 | |
1965aae3 | 597 | #endif /* _ASM_X86_UACCESS_H */ |
8174c430 | 598 |