diff options
author | Thomas Gleixner <tglx@linutronix.de> | 2007-10-11 05:20:03 -0400 |
---|---|---|
committer | Thomas Gleixner <tglx@linutronix.de> | 2007-10-11 05:20:03 -0400 |
commit | 96a388de5dc53a8b234b3fd41f3ae2cedc9ffd42 (patch) | |
tree | d947a467aa2da3140279617bc4b9b101640d7bf4 /include/asm-x86/uaccess_32.h | |
parent | 27bd0c955648646abf2a353a8371d28c37bcd982 (diff) |
i386/x86_64: move headers to include/asm-x86
Move the headers to include/asm-x86 and fixup the
header install make rules
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'include/asm-x86/uaccess_32.h')
-rw-r--r-- | include/asm-x86/uaccess_32.h | 590 |
1 files changed, 590 insertions, 0 deletions
diff --git a/include/asm-x86/uaccess_32.h b/include/asm-x86/uaccess_32.h new file mode 100644 index 000000000000..d2a4f7be9c2c --- /dev/null +++ b/include/asm-x86/uaccess_32.h | |||
@@ -0,0 +1,590 @@ | |||
1 | #ifndef __i386_UACCESS_H | ||
2 | #define __i386_UACCESS_H | ||
3 | |||
4 | /* | ||
5 | * User space memory access functions | ||
6 | */ | ||
7 | #include <linux/errno.h> | ||
8 | #include <linux/thread_info.h> | ||
9 | #include <linux/prefetch.h> | ||
10 | #include <linux/string.h> | ||
11 | #include <asm/page.h> | ||
12 | |||
13 | #define VERIFY_READ 0 | ||
14 | #define VERIFY_WRITE 1 | ||
15 | |||
16 | /* | ||
17 | * The fs value determines whether argument validity checking should be | ||
18 | * performed or not. If get_fs() == USER_DS, checking is performed, with | ||
19 | * get_fs() == KERNEL_DS, checking is bypassed. | ||
20 | * | ||
21 | * For historical reasons, these macros are grossly misnamed. | ||
22 | */ | ||
23 | |||
24 | #define MAKE_MM_SEG(s) ((mm_segment_t) { (s) }) | ||
25 | |||
26 | |||
27 | #define KERNEL_DS MAKE_MM_SEG(0xFFFFFFFFUL) | ||
28 | #define USER_DS MAKE_MM_SEG(PAGE_OFFSET) | ||
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 | |||
36 | /* | ||
37 | * movsl can be slow when source and dest are not both 8-byte aligned | ||
38 | */ | ||
39 | #ifdef CONFIG_X86_INTEL_USERCOPY | ||
40 | extern struct movsl_mask { | ||
41 | int mask; | ||
42 | } ____cacheline_aligned_in_smp movsl_mask; | ||
43 | #endif | ||
44 | |||
45 | #define __addr_ok(addr) ((unsigned long __force)(addr) < (current_thread_info()->addr_limit.seg)) | ||
46 | |||
47 | /* | ||
48 | * Test whether a block of memory is a valid user space address. | ||
49 | * Returns 0 if the range is valid, nonzero otherwise. | ||
50 | * | ||
51 | * This is equivalent to the following test: | ||
52 | * (u33)addr + (u33)size >= (u33)current->addr_limit.seg | ||
53 | * | ||
54 | * This needs 33-bit arithmetic. We have a carry... | ||
55 | */ | ||
56 | #define __range_ok(addr,size) ({ \ | ||
57 | unsigned long flag,roksum; \ | ||
58 | __chk_user_ptr(addr); \ | ||
59 | asm("addl %3,%1 ; sbbl %0,%0; cmpl %1,%4; sbbl $0,%0" \ | ||
60 | :"=&r" (flag), "=r" (roksum) \ | ||
61 | :"1" (addr),"g" ((int)(size)),"rm" (current_thread_info()->addr_limit.seg)); \ | ||
62 | flag; }) | ||
63 | |||
64 | /** | ||
65 | * access_ok: - Checks if a user space pointer is valid | ||
66 | * @type: Type of access: %VERIFY_READ or %VERIFY_WRITE. Note that | ||
67 | * %VERIFY_WRITE is a superset of %VERIFY_READ - if it is safe | ||
68 | * to write to a block, it is always safe to read from it. | ||
69 | * @addr: User space pointer to start of block to check | ||
70 | * @size: Size of block to check | ||
71 | * | ||
72 | * Context: User context only. This function may sleep. | ||
73 | * | ||
74 | * Checks if a pointer to a block of memory in user space is valid. | ||
75 | * | ||
76 | * Returns true (nonzero) if the memory block may be valid, false (zero) | ||
77 | * if it is definitely invalid. | ||
78 | * | ||
79 | * Note that, depending on architecture, this function probably just | ||
80 | * checks that the pointer is in the user space range - after calling | ||
81 | * this function, memory access functions may still return -EFAULT. | ||
82 | */ | ||
83 | #define access_ok(type,addr,size) (likely(__range_ok(addr,size) == 0)) | ||
84 | |||
85 | /* | ||
86 | * The exception table consists of pairs of addresses: the first is the | ||
87 | * address of an instruction that is allowed to fault, and the second is | ||
88 | * the address at which the program should continue. No registers are | ||
89 | * modified, so it is entirely up to the continuation code to figure out | ||
90 | * what to do. | ||
91 | * | ||
92 | * All the routines below use bits of fixup code that are out of line | ||
93 | * with the main instruction path. This means when everything is well, | ||
94 | * we don't even have to jump over them. Further, they do not intrude | ||
95 | * on our cache or tlb entries. | ||
96 | */ | ||
97 | |||
98 | struct exception_table_entry | ||
99 | { | ||
100 | unsigned long insn, fixup; | ||
101 | }; | ||
102 | |||
103 | extern int fixup_exception(struct pt_regs *regs); | ||
104 | |||
105 | /* | ||
106 | * These are the main single-value transfer routines. They automatically | ||
107 | * use the right size if we just have the right pointer type. | ||
108 | * | ||
109 | * This gets kind of ugly. We want to return _two_ values in "get_user()" | ||
110 | * and yet we don't want to do any pointers, because that is too much | ||
111 | * of a performance impact. Thus we have a few rather ugly macros here, | ||
112 | * and hide all the ugliness from the user. | ||
113 | * | ||
114 | * The "__xxx" versions of the user access functions are versions that | ||
115 | * do not verify the address space, that must have been done previously | ||
116 | * with a separate "access_ok()" call (this is used when we do multiple | ||
117 | * accesses to the same area of user memory). | ||
118 | */ | ||
119 | |||
120 | extern void __get_user_1(void); | ||
121 | extern void __get_user_2(void); | ||
122 | extern void __get_user_4(void); | ||
123 | |||
124 | #define __get_user_x(size,ret,x,ptr) \ | ||
125 | __asm__ __volatile__("call __get_user_" #size \ | ||
126 | :"=a" (ret),"=d" (x) \ | ||
127 | :"0" (ptr)) | ||
128 | |||
129 | |||
130 | /* Careful: we have to cast the result to the type of the pointer for sign reasons */ | ||
131 | /** | ||
132 | * get_user: - Get a simple variable from user space. | ||
133 | * @x: Variable to store result. | ||
134 | * @ptr: Source address, in user space. | ||
135 | * | ||
136 | * Context: User context only. This function may sleep. | ||
137 | * | ||
138 | * This macro copies a single simple variable from user space to kernel | ||
139 | * space. It supports simple types like char and int, but not larger | ||
140 | * data types like structures or arrays. | ||
141 | * | ||
142 | * @ptr must have pointer-to-simple-variable type, and the result of | ||
143 | * dereferencing @ptr must be assignable to @x without a cast. | ||
144 | * | ||
145 | * Returns zero on success, or -EFAULT on error. | ||
146 | * On error, the variable @x is set to zero. | ||
147 | */ | ||
148 | #define get_user(x,ptr) \ | ||
149 | ({ int __ret_gu; \ | ||
150 | unsigned long __val_gu; \ | ||
151 | __chk_user_ptr(ptr); \ | ||
152 | switch(sizeof (*(ptr))) { \ | ||
153 | case 1: __get_user_x(1,__ret_gu,__val_gu,ptr); break; \ | ||
154 | case 2: __get_user_x(2,__ret_gu,__val_gu,ptr); break; \ | ||
155 | case 4: __get_user_x(4,__ret_gu,__val_gu,ptr); break; \ | ||
156 | default: __get_user_x(X,__ret_gu,__val_gu,ptr); break; \ | ||
157 | } \ | ||
158 | (x) = (__typeof__(*(ptr)))__val_gu; \ | ||
159 | __ret_gu; \ | ||
160 | }) | ||
161 | |||
162 | extern void __put_user_bad(void); | ||
163 | |||
164 | /* | ||
165 | * Strange magic calling convention: pointer in %ecx, | ||
166 | * value in %eax(:%edx), return value in %eax, no clobbers. | ||
167 | */ | ||
168 | extern void __put_user_1(void); | ||
169 | extern void __put_user_2(void); | ||
170 | extern void __put_user_4(void); | ||
171 | extern void __put_user_8(void); | ||
172 | |||
173 | #define __put_user_1(x, ptr) __asm__ __volatile__("call __put_user_1":"=a" (__ret_pu):"0" ((typeof(*(ptr)))(x)), "c" (ptr)) | ||
174 | #define __put_user_2(x, ptr) __asm__ __volatile__("call __put_user_2":"=a" (__ret_pu):"0" ((typeof(*(ptr)))(x)), "c" (ptr)) | ||
175 | #define __put_user_4(x, ptr) __asm__ __volatile__("call __put_user_4":"=a" (__ret_pu):"0" ((typeof(*(ptr)))(x)), "c" (ptr)) | ||
176 | #define __put_user_8(x, ptr) __asm__ __volatile__("call __put_user_8":"=a" (__ret_pu):"A" ((typeof(*(ptr)))(x)), "c" (ptr)) | ||
177 | #define __put_user_X(x, ptr) __asm__ __volatile__("call __put_user_X":"=a" (__ret_pu):"c" (ptr)) | ||
178 | |||
179 | /** | ||
180 | * put_user: - Write a simple value into user space. | ||
181 | * @x: Value to copy to user space. | ||
182 | * @ptr: Destination address, in user space. | ||
183 | * | ||
184 | * Context: User context only. This function may sleep. | ||
185 | * | ||
186 | * This macro copies a single simple value from kernel space to user | ||
187 | * space. It supports simple types like char and int, but not larger | ||
188 | * data types like structures or arrays. | ||
189 | * | ||
190 | * @ptr must have pointer-to-simple-variable type, and @x must be assignable | ||
191 | * to the result of dereferencing @ptr. | ||
192 | * | ||
193 | * Returns zero on success, or -EFAULT on error. | ||
194 | */ | ||
195 | #ifdef CONFIG_X86_WP_WORKS_OK | ||
196 | |||
197 | #define put_user(x,ptr) \ | ||
198 | ({ int __ret_pu; \ | ||
199 | __typeof__(*(ptr)) __pu_val; \ | ||
200 | __chk_user_ptr(ptr); \ | ||
201 | __pu_val = x; \ | ||
202 | switch(sizeof(*(ptr))) { \ | ||
203 | case 1: __put_user_1(__pu_val, ptr); break; \ | ||
204 | case 2: __put_user_2(__pu_val, ptr); break; \ | ||
205 | case 4: __put_user_4(__pu_val, ptr); break; \ | ||
206 | case 8: __put_user_8(__pu_val, ptr); break; \ | ||
207 | default:__put_user_X(__pu_val, ptr); break; \ | ||
208 | } \ | ||
209 | __ret_pu; \ | ||
210 | }) | ||
211 | |||
212 | #else | ||
213 | #define put_user(x,ptr) \ | ||
214 | ({ \ | ||
215 | int __ret_pu; \ | ||
216 | __typeof__(*(ptr)) __pus_tmp = x; \ | ||
217 | __ret_pu=0; \ | ||
218 | if(unlikely(__copy_to_user_ll(ptr, &__pus_tmp, \ | ||
219 | sizeof(*(ptr))) != 0)) \ | ||
220 | __ret_pu=-EFAULT; \ | ||
221 | __ret_pu; \ | ||
222 | }) | ||
223 | |||
224 | |||
225 | #endif | ||
226 | |||
227 | /** | ||
228 | * __get_user: - Get a simple variable from user space, with less checking. | ||
229 | * @x: Variable to store result. | ||
230 | * @ptr: Source address, in user space. | ||
231 | * | ||
232 | * Context: User context only. This function may sleep. | ||
233 | * | ||
234 | * This macro copies a single simple variable from user space to kernel | ||
235 | * space. It supports simple types like char and int, but not larger | ||
236 | * data types like structures or arrays. | ||
237 | * | ||
238 | * @ptr must have pointer-to-simple-variable type, and the result of | ||
239 | * dereferencing @ptr must be assignable to @x without a cast. | ||
240 | * | ||
241 | * Caller must check the pointer with access_ok() before calling this | ||
242 | * function. | ||
243 | * | ||
244 | * Returns zero on success, or -EFAULT on error. | ||
245 | * On error, the variable @x is set to zero. | ||
246 | */ | ||
247 | #define __get_user(x,ptr) \ | ||
248 | __get_user_nocheck((x),(ptr),sizeof(*(ptr))) | ||
249 | |||
250 | |||
251 | /** | ||
252 | * __put_user: - Write a simple value into user space, with less checking. | ||
253 | * @x: Value to copy to user space. | ||
254 | * @ptr: Destination address, in user space. | ||
255 | * | ||
256 | * Context: User context only. This function may sleep. | ||
257 | * | ||
258 | * This macro copies a single simple value from kernel space to user | ||
259 | * space. It supports simple types like char and int, but not larger | ||
260 | * data types like structures or arrays. | ||
261 | * | ||
262 | * @ptr must have pointer-to-simple-variable type, and @x must be assignable | ||
263 | * to the result of dereferencing @ptr. | ||
264 | * | ||
265 | * Caller must check the pointer with access_ok() before calling this | ||
266 | * function. | ||
267 | * | ||
268 | * Returns zero on success, or -EFAULT on error. | ||
269 | */ | ||
270 | #define __put_user(x,ptr) \ | ||
271 | __put_user_nocheck((__typeof__(*(ptr)))(x),(ptr),sizeof(*(ptr))) | ||
272 | |||
273 | #define __put_user_nocheck(x,ptr,size) \ | ||
274 | ({ \ | ||
275 | long __pu_err; \ | ||
276 | __put_user_size((x),(ptr),(size),__pu_err,-EFAULT); \ | ||
277 | __pu_err; \ | ||
278 | }) | ||
279 | |||
280 | |||
281 | #define __put_user_u64(x, addr, err) \ | ||
282 | __asm__ __volatile__( \ | ||
283 | "1: movl %%eax,0(%2)\n" \ | ||
284 | "2: movl %%edx,4(%2)\n" \ | ||
285 | "3:\n" \ | ||
286 | ".section .fixup,\"ax\"\n" \ | ||
287 | "4: movl %3,%0\n" \ | ||
288 | " jmp 3b\n" \ | ||
289 | ".previous\n" \ | ||
290 | ".section __ex_table,\"a\"\n" \ | ||
291 | " .align 4\n" \ | ||
292 | " .long 1b,4b\n" \ | ||
293 | " .long 2b,4b\n" \ | ||
294 | ".previous" \ | ||
295 | : "=r"(err) \ | ||
296 | : "A" (x), "r" (addr), "i"(-EFAULT), "0"(err)) | ||
297 | |||
298 | #ifdef CONFIG_X86_WP_WORKS_OK | ||
299 | |||
300 | #define __put_user_size(x,ptr,size,retval,errret) \ | ||
301 | do { \ | ||
302 | retval = 0; \ | ||
303 | __chk_user_ptr(ptr); \ | ||
304 | switch (size) { \ | ||
305 | case 1: __put_user_asm(x,ptr,retval,"b","b","iq",errret);break; \ | ||
306 | case 2: __put_user_asm(x,ptr,retval,"w","w","ir",errret);break; \ | ||
307 | case 4: __put_user_asm(x,ptr,retval,"l","","ir",errret); break; \ | ||
308 | case 8: __put_user_u64((__typeof__(*ptr))(x),ptr,retval); break;\ | ||
309 | default: __put_user_bad(); \ | ||
310 | } \ | ||
311 | } while (0) | ||
312 | |||
313 | #else | ||
314 | |||
315 | #define __put_user_size(x,ptr,size,retval,errret) \ | ||
316 | do { \ | ||
317 | __typeof__(*(ptr)) __pus_tmp = x; \ | ||
318 | retval = 0; \ | ||
319 | \ | ||
320 | if(unlikely(__copy_to_user_ll(ptr, &__pus_tmp, size) != 0)) \ | ||
321 | retval = errret; \ | ||
322 | } while (0) | ||
323 | |||
324 | #endif | ||
325 | struct __large_struct { unsigned long buf[100]; }; | ||
326 | #define __m(x) (*(struct __large_struct __user *)(x)) | ||
327 | |||
328 | /* | ||
329 | * Tell gcc we read from memory instead of writing: this is because | ||
330 | * we do not write to any memory gcc knows about, so there are no | ||
331 | * aliasing issues. | ||
332 | */ | ||
333 | #define __put_user_asm(x, addr, err, itype, rtype, ltype, errret) \ | ||
334 | __asm__ __volatile__( \ | ||
335 | "1: mov"itype" %"rtype"1,%2\n" \ | ||
336 | "2:\n" \ | ||
337 | ".section .fixup,\"ax\"\n" \ | ||
338 | "3: movl %3,%0\n" \ | ||
339 | " jmp 2b\n" \ | ||
340 | ".previous\n" \ | ||
341 | ".section __ex_table,\"a\"\n" \ | ||
342 | " .align 4\n" \ | ||
343 | " .long 1b,3b\n" \ | ||
344 | ".previous" \ | ||
345 | : "=r"(err) \ | ||
346 | : ltype (x), "m"(__m(addr)), "i"(errret), "0"(err)) | ||
347 | |||
348 | |||
349 | #define __get_user_nocheck(x,ptr,size) \ | ||
350 | ({ \ | ||
351 | long __gu_err; \ | ||
352 | unsigned long __gu_val; \ | ||
353 | __get_user_size(__gu_val,(ptr),(size),__gu_err,-EFAULT);\ | ||
354 | (x) = (__typeof__(*(ptr)))__gu_val; \ | ||
355 | __gu_err; \ | ||
356 | }) | ||
357 | |||
358 | extern long __get_user_bad(void); | ||
359 | |||
360 | #define __get_user_size(x,ptr,size,retval,errret) \ | ||
361 | do { \ | ||
362 | retval = 0; \ | ||
363 | __chk_user_ptr(ptr); \ | ||
364 | switch (size) { \ | ||
365 | case 1: __get_user_asm(x,ptr,retval,"b","b","=q",errret);break; \ | ||
366 | case 2: __get_user_asm(x,ptr,retval,"w","w","=r",errret);break; \ | ||
367 | case 4: __get_user_asm(x,ptr,retval,"l","","=r",errret);break; \ | ||
368 | default: (x) = __get_user_bad(); \ | ||
369 | } \ | ||
370 | } while (0) | ||
371 | |||
372 | #define __get_user_asm(x, addr, err, itype, rtype, ltype, errret) \ | ||
373 | __asm__ __volatile__( \ | ||
374 | "1: mov"itype" %2,%"rtype"1\n" \ | ||
375 | "2:\n" \ | ||
376 | ".section .fixup,\"ax\"\n" \ | ||
377 | "3: movl %3,%0\n" \ | ||
378 | " xor"itype" %"rtype"1,%"rtype"1\n" \ | ||
379 | " jmp 2b\n" \ | ||
380 | ".previous\n" \ | ||
381 | ".section __ex_table,\"a\"\n" \ | ||
382 | " .align 4\n" \ | ||
383 | " .long 1b,3b\n" \ | ||
384 | ".previous" \ | ||
385 | : "=r"(err), ltype (x) \ | ||
386 | : "m"(__m(addr)), "i"(errret), "0"(err)) | ||
387 | |||
388 | |||
389 | unsigned long __must_check __copy_to_user_ll(void __user *to, | ||
390 | const void *from, unsigned long n); | ||
391 | unsigned long __must_check __copy_from_user_ll(void *to, | ||
392 | const void __user *from, unsigned long n); | ||
393 | unsigned long __must_check __copy_from_user_ll_nozero(void *to, | ||
394 | const void __user *from, unsigned long n); | ||
395 | unsigned long __must_check __copy_from_user_ll_nocache(void *to, | ||
396 | const void __user *from, unsigned long n); | ||
397 | unsigned long __must_check __copy_from_user_ll_nocache_nozero(void *to, | ||
398 | const void __user *from, unsigned long n); | ||
399 | |||
400 | /** | ||
401 | * __copy_to_user_inatomic: - Copy a block of data into user space, with less checking. | ||
402 | * @to: Destination address, in user space. | ||
403 | * @from: Source address, in kernel space. | ||
404 | * @n: Number of bytes to copy. | ||
405 | * | ||
406 | * Context: User context only. | ||
407 | * | ||
408 | * Copy data from kernel space to user space. Caller must check | ||
409 | * the specified block with access_ok() before calling this function. | ||
410 | * The caller should also make sure he pins the user space address | ||
411 | * so that the we don't result in page fault and sleep. | ||
412 | * | ||
413 | * Here we special-case 1, 2 and 4-byte copy_*_user invocations. On a fault | ||
414 | * we return the initial request size (1, 2 or 4), as copy_*_user should do. | ||
415 | * If a store crosses a page boundary and gets a fault, the x86 will not write | ||
416 | * anything, so this is accurate. | ||
417 | */ | ||
418 | |||
419 | static __always_inline unsigned long __must_check | ||
420 | __copy_to_user_inatomic(void __user *to, const void *from, unsigned long n) | ||
421 | { | ||
422 | if (__builtin_constant_p(n)) { | ||
423 | unsigned long ret; | ||
424 | |||
425 | switch (n) { | ||
426 | case 1: | ||
427 | __put_user_size(*(u8 *)from, (u8 __user *)to, 1, ret, 1); | ||
428 | return ret; | ||
429 | case 2: | ||
430 | __put_user_size(*(u16 *)from, (u16 __user *)to, 2, ret, 2); | ||
431 | return ret; | ||
432 | case 4: | ||
433 | __put_user_size(*(u32 *)from, (u32 __user *)to, 4, ret, 4); | ||
434 | return ret; | ||
435 | } | ||
436 | } | ||
437 | return __copy_to_user_ll(to, from, n); | ||
438 | } | ||
439 | |||
440 | /** | ||
441 | * __copy_to_user: - Copy a block of data into user space, with less checking. | ||
442 | * @to: Destination address, in user space. | ||
443 | * @from: Source address, in kernel space. | ||
444 | * @n: Number of bytes to copy. | ||
445 | * | ||
446 | * Context: User context only. This function may sleep. | ||
447 | * | ||
448 | * Copy data from kernel space to user space. Caller must check | ||
449 | * the specified block with access_ok() before calling this function. | ||
450 | * | ||
451 | * Returns number of bytes that could not be copied. | ||
452 | * On success, this will be zero. | ||
453 | */ | ||
454 | static __always_inline unsigned long __must_check | ||
455 | __copy_to_user(void __user *to, const void *from, unsigned long n) | ||
456 | { | ||
457 | might_sleep(); | ||
458 | return __copy_to_user_inatomic(to, from, n); | ||
459 | } | ||
460 | |||
461 | static __always_inline unsigned long | ||
462 | __copy_from_user_inatomic(void *to, const void __user *from, unsigned long n) | ||
463 | { | ||
464 | /* Avoid zeroing the tail if the copy fails.. | ||
465 | * If 'n' is constant and 1, 2, or 4, we do still zero on a failure, | ||
466 | * but as the zeroing behaviour is only significant when n is not | ||
467 | * constant, that shouldn't be a problem. | ||
468 | */ | ||
469 | if (__builtin_constant_p(n)) { | ||
470 | unsigned long ret; | ||
471 | |||
472 | switch (n) { | ||
473 | case 1: | ||
474 | __get_user_size(*(u8 *)to, from, 1, ret, 1); | ||
475 | return ret; | ||
476 | case 2: | ||
477 | __get_user_size(*(u16 *)to, from, 2, ret, 2); | ||
478 | return ret; | ||
479 | case 4: | ||
480 | __get_user_size(*(u32 *)to, from, 4, ret, 4); | ||
481 | return ret; | ||
482 | } | ||
483 | } | ||
484 | return __copy_from_user_ll_nozero(to, from, n); | ||
485 | } | ||
486 | |||
487 | /** | ||
488 | * __copy_from_user: - Copy a block of data from user space, with less checking. | ||
489 | * @to: Destination address, in kernel space. | ||
490 | * @from: Source address, in user space. | ||
491 | * @n: Number of bytes to copy. | ||
492 | * | ||
493 | * Context: User context only. This function may sleep. | ||
494 | * | ||
495 | * Copy data from user space to kernel space. Caller must check | ||
496 | * the specified block with access_ok() before calling this function. | ||
497 | * | ||
498 | * Returns number of bytes that could not be copied. | ||
499 | * On success, this will be zero. | ||
500 | * | ||
501 | * If some data could not be copied, this function will pad the copied | ||
502 | * data to the requested size using zero bytes. | ||
503 | * | ||
504 | * An alternate version - __copy_from_user_inatomic() - may be called from | ||
505 | * atomic context and will fail rather than sleep. In this case the | ||
506 | * uncopied bytes will *NOT* be padded with zeros. See fs/filemap.h | ||
507 | * for explanation of why this is needed. | ||
508 | */ | ||
509 | static __always_inline unsigned long | ||
510 | __copy_from_user(void *to, const void __user *from, unsigned long n) | ||
511 | { | ||
512 | might_sleep(); | ||
513 | if (__builtin_constant_p(n)) { | ||
514 | unsigned long ret; | ||
515 | |||
516 | switch (n) { | ||
517 | case 1: | ||
518 | __get_user_size(*(u8 *)to, from, 1, ret, 1); | ||
519 | return ret; | ||
520 | case 2: | ||
521 | __get_user_size(*(u16 *)to, from, 2, ret, 2); | ||
522 | return ret; | ||
523 | case 4: | ||
524 | __get_user_size(*(u32 *)to, from, 4, ret, 4); | ||
525 | return ret; | ||
526 | } | ||
527 | } | ||
528 | return __copy_from_user_ll(to, from, n); | ||
529 | } | ||
530 | |||
531 | #define ARCH_HAS_NOCACHE_UACCESS | ||
532 | |||
533 | static __always_inline unsigned long __copy_from_user_nocache(void *to, | ||
534 | const void __user *from, unsigned long n) | ||
535 | { | ||
536 | might_sleep(); | ||
537 | if (__builtin_constant_p(n)) { | ||
538 | unsigned long ret; | ||
539 | |||
540 | switch (n) { | ||
541 | case 1: | ||
542 | __get_user_size(*(u8 *)to, from, 1, ret, 1); | ||
543 | return ret; | ||
544 | case 2: | ||
545 | __get_user_size(*(u16 *)to, from, 2, ret, 2); | ||
546 | return ret; | ||
547 | case 4: | ||
548 | __get_user_size(*(u32 *)to, from, 4, ret, 4); | ||
549 | return ret; | ||
550 | } | ||
551 | } | ||
552 | return __copy_from_user_ll_nocache(to, from, n); | ||
553 | } | ||
554 | |||
555 | static __always_inline unsigned long | ||
556 | __copy_from_user_inatomic_nocache(void *to, const void __user *from, unsigned long n) | ||
557 | { | ||
558 | return __copy_from_user_ll_nocache_nozero(to, from, n); | ||
559 | } | ||
560 | |||
561 | unsigned long __must_check copy_to_user(void __user *to, | ||
562 | const void *from, unsigned long n); | ||
563 | unsigned long __must_check copy_from_user(void *to, | ||
564 | const void __user *from, unsigned long n); | ||
565 | long __must_check strncpy_from_user(char *dst, const char __user *src, | ||
566 | long count); | ||
567 | long __must_check __strncpy_from_user(char *dst, | ||
568 | const char __user *src, long count); | ||
569 | |||
570 | /** | ||
571 | * strlen_user: - Get the size of a string in user space. | ||
572 | * @str: The string to measure. | ||
573 | * | ||
574 | * Context: User context only. This function may sleep. | ||
575 | * | ||
576 | * Get the size of a NUL-terminated string in user space. | ||
577 | * | ||
578 | * Returns the size of the string INCLUDING the terminating NUL. | ||
579 | * On exception, returns 0. | ||
580 | * | ||
581 | * If there is a limit on the length of a valid string, you may wish to | ||
582 | * consider using strnlen_user() instead. | ||
583 | */ | ||
584 | #define strlen_user(str) strnlen_user(str, LONG_MAX) | ||
585 | |||
586 | long strnlen_user(const char __user *str, long n); | ||
587 | unsigned long __must_check clear_user(void __user *mem, unsigned long len); | ||
588 | unsigned long __must_check __clear_user(void __user *mem, unsigned long len); | ||
589 | |||
590 | #endif /* __i386_UACCESS_H */ | ||