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1/*
2 * This file is subject to the terms and conditions of the GNU General Public
3 * License. See the file "COPYING" in the main directory of this archive
4 * for more details.
5 *
6 * Copyright (C) 1996, 1997, 1998, 1999, 2000, 03, 04 by Ralf Baechle
7 * Copyright (C) 1999, 2000 Silicon Graphics, Inc.
8 * Copyright (C) 2007 Maciej W. Rozycki
9 * Copyright (C) 2014, Imagination Technologies Ltd.
10 */
11#ifndef _ASM_UACCESS_H
12#define _ASM_UACCESS_H
13
14#include <linux/kernel.h>
15#include <linux/string.h>
16#include <asm/asm-eva.h>
17#include <asm/extable.h>
18
19#ifdef CONFIG_32BIT
20
21#define __UA_LIMIT 0x80000000UL
22#define TASK_SIZE_MAX KSEG0
23
24#define __UA_ADDR ".word"
25#define __UA_LA "la"
26#define __UA_ADDU "addu"
27#define __UA_t0 "$8"
28#define __UA_t1 "$9"
29
30#endif /* CONFIG_32BIT */
31
32#ifdef CONFIG_64BIT
33
34extern u64 __ua_limit;
35
36#define __UA_LIMIT __ua_limit
37#define TASK_SIZE_MAX XKSSEG
38
39#define __UA_ADDR ".dword"
40#define __UA_LA "dla"
41#define __UA_ADDU "daddu"
42#define __UA_t0 "$12"
43#define __UA_t1 "$13"
44
45#endif /* CONFIG_64BIT */
46
47#include <asm-generic/access_ok.h>
48
49/*
50 * put_user: - Write a simple value into user space.
51 * @x: Value to copy to user space.
52 * @ptr: Destination address, in user space.
53 *
54 * Context: User context only. This function may sleep if pagefaults are
55 * enabled.
56 *
57 * This macro copies a single simple value from kernel space to user
58 * space. It supports simple types like char and int, but not larger
59 * data types like structures or arrays.
60 *
61 * @ptr must have pointer-to-simple-variable type, and @x must be assignable
62 * to the result of dereferencing @ptr.
63 *
64 * Returns zero on success, or -EFAULT on error.
65 */
66#define put_user(x, ptr) \
67({ \
68 __typeof__(*(ptr)) __user *__p = (ptr); \
69 \
70 might_fault(); \
71 access_ok(__p, sizeof(*__p)) ? __put_user((x), __p) : -EFAULT; \
72})
73
74/*
75 * get_user: - Get a simple variable from user space.
76 * @x: Variable to store result.
77 * @ptr: Source address, in user space.
78 *
79 * Context: User context only. This function may sleep if pagefaults are
80 * enabled.
81 *
82 * This macro copies a single simple variable from user space to kernel
83 * space. It supports simple types like char and int, but not larger
84 * data types like structures or arrays.
85 *
86 * @ptr must have pointer-to-simple-variable type, and the result of
87 * dereferencing @ptr must be assignable to @x without a cast.
88 *
89 * Returns zero on success, or -EFAULT on error.
90 * On error, the variable @x is set to zero.
91 */
92#define get_user(x, ptr) \
93({ \
94 const __typeof__(*(ptr)) __user *__p = (ptr); \
95 \
96 might_fault(); \
97 access_ok(__p, sizeof(*__p)) ? __get_user((x), __p) : \
98 ((x) = 0, -EFAULT); \
99})
100
101/*
102 * __put_user: - Write a simple value into user space, with less checking.
103 * @x: Value to copy to user space.
104 * @ptr: Destination address, in user space.
105 *
106 * Context: User context only. This function may sleep if pagefaults are
107 * enabled.
108 *
109 * This macro copies a single simple value from kernel space to user
110 * space. It supports simple types like char and int, but not larger
111 * data types like structures or arrays.
112 *
113 * @ptr must have pointer-to-simple-variable type, and @x must be assignable
114 * to the result of dereferencing @ptr.
115 *
116 * Caller must check the pointer with access_ok() before calling this
117 * function.
118 *
119 * Returns zero on success, or -EFAULT on error.
120 */
121#define __put_user(x, ptr) \
122({ \
123 __typeof__(*(ptr)) __user *__pu_ptr = (ptr); \
124 __typeof__(*(ptr)) __pu_val = (x); \
125 int __pu_err = 0; \
126 \
127 __chk_user_ptr(__pu_ptr); \
128 switch (sizeof(*__pu_ptr)) { \
129 case 1: \
130 __put_data_asm(user_sb, __pu_ptr); \
131 break; \
132 case 2: \
133 __put_data_asm(user_sh, __pu_ptr); \
134 break; \
135 case 4: \
136 __put_data_asm(user_sw, __pu_ptr); \
137 break; \
138 case 8: \
139 __PUT_DW(user_sd, __pu_ptr); \
140 break; \
141 default: \
142 BUILD_BUG(); \
143 } \
144 \
145 __pu_err; \
146})
147
148/*
149 * __get_user: - Get a simple variable from user space, with less checking.
150 * @x: Variable to store result.
151 * @ptr: Source address, in user space.
152 *
153 * Context: User context only. This function may sleep if pagefaults are
154 * enabled.
155 *
156 * This macro copies a single simple variable from user space to kernel
157 * space. It supports simple types like char and int, but not larger
158 * data types like structures or arrays.
159 *
160 * @ptr must have pointer-to-simple-variable type, and the result of
161 * dereferencing @ptr must be assignable to @x without a cast.
162 *
163 * Caller must check the pointer with access_ok() before calling this
164 * function.
165 *
166 * Returns zero on success, or -EFAULT on error.
167 * On error, the variable @x is set to zero.
168 */
169#define __get_user(x, ptr) \
170({ \
171 const __typeof__(*(ptr)) __user *__gu_ptr = (ptr); \
172 int __gu_err = 0; \
173 \
174 __chk_user_ptr(__gu_ptr); \
175 switch (sizeof(*__gu_ptr)) { \
176 case 1: \
177 __get_data_asm((x), user_lb, __gu_ptr); \
178 break; \
179 case 2: \
180 __get_data_asm((x), user_lh, __gu_ptr); \
181 break; \
182 case 4: \
183 __get_data_asm((x), user_lw, __gu_ptr); \
184 break; \
185 case 8: \
186 __GET_DW((x), user_ld, __gu_ptr); \
187 break; \
188 default: \
189 BUILD_BUG(); \
190 } \
191 \
192 __gu_err; \
193})
194
195struct __large_struct { unsigned long buf[100]; };
196#define __m(x) (*(struct __large_struct __user *)(x))
197
198#ifdef CONFIG_32BIT
199#define __GET_DW(val, insn, ptr) __get_data_asm_ll32(val, insn, ptr)
200#endif
201#ifdef CONFIG_64BIT
202#define __GET_DW(val, insn, ptr) __get_data_asm(val, insn, ptr)
203#endif
204
205#define __get_data_asm(val, insn, addr) \
206{ \
207 long __gu_tmp; \
208 \
209 __asm__ __volatile__( \
210 "1: "insn("%1", "%3")" \n" \
211 "2: \n" \
212 " .insn \n" \
213 " .section .fixup,\"ax\" \n" \
214 "3: li %0, %4 \n" \
215 " move %1, $0 \n" \
216 " j 2b \n" \
217 " .previous \n" \
218 " .section __ex_table,\"a\" \n" \
219 " "__UA_ADDR "\t1b, 3b \n" \
220 " .previous \n" \
221 : "=r" (__gu_err), "=r" (__gu_tmp) \
222 : "0" (0), "o" (__m(addr)), "i" (-EFAULT)); \
223 \
224 (val) = (__typeof__(*(addr))) __gu_tmp; \
225}
226
227/*
228 * Get a long long 64 using 32 bit registers.
229 */
230#define __get_data_asm_ll32(val, insn, addr) \
231{ \
232 union { \
233 unsigned long long l; \
234 __typeof__(*(addr)) t; \
235 } __gu_tmp; \
236 \
237 __asm__ __volatile__( \
238 "1: " insn("%1", "(%3)")" \n" \
239 "2: " insn("%D1", "4(%3)")" \n" \
240 "3: \n" \
241 " .insn \n" \
242 " .section .fixup,\"ax\" \n" \
243 "4: li %0, %4 \n" \
244 " move %1, $0 \n" \
245 " move %D1, $0 \n" \
246 " j 3b \n" \
247 " .previous \n" \
248 " .section __ex_table,\"a\" \n" \
249 " " __UA_ADDR " 1b, 4b \n" \
250 " " __UA_ADDR " 2b, 4b \n" \
251 " .previous \n" \
252 : "=r" (__gu_err), "=&r" (__gu_tmp.l) \
253 : "0" (0), "r" (addr), "i" (-EFAULT)); \
254 \
255 (val) = __gu_tmp.t; \
256}
257
258#define __get_kernel_nofault(dst, src, type, err_label) \
259do { \
260 int __gu_err; \
261 \
262 switch (sizeof(type)) { \
263 case 1: \
264 __get_data_asm(*(type *)(dst), kernel_lb, \
265 (__force type *)(src)); \
266 break; \
267 case 2: \
268 __get_data_asm(*(type *)(dst), kernel_lh, \
269 (__force type *)(src)); \
270 break; \
271 case 4: \
272 __get_data_asm(*(type *)(dst), kernel_lw, \
273 (__force type *)(src)); \
274 break; \
275 case 8: \
276 __GET_DW(*(type *)(dst), kernel_ld, \
277 (__force type *)(src)); \
278 break; \
279 default: \
280 BUILD_BUG(); \
281 break; \
282 } \
283 if (unlikely(__gu_err)) \
284 goto err_label; \
285} while (0)
286
287/*
288 * Yuck. We need two variants, one for 64bit operation and one
289 * for 32 bit mode and old iron.
290 */
291#ifdef CONFIG_32BIT
292#define __PUT_DW(insn, ptr) __put_data_asm_ll32(insn, ptr)
293#endif
294#ifdef CONFIG_64BIT
295#define __PUT_DW(insn, ptr) __put_data_asm(insn, ptr)
296#endif
297
298#define __put_data_asm(insn, ptr) \
299{ \
300 __asm__ __volatile__( \
301 "1: "insn("%z2", "%3")" # __put_data_asm \n" \
302 "2: \n" \
303 " .insn \n" \
304 " .section .fixup,\"ax\" \n" \
305 "3: li %0, %4 \n" \
306 " j 2b \n" \
307 " .previous \n" \
308 " .section __ex_table,\"a\" \n" \
309 " " __UA_ADDR " 1b, 3b \n" \
310 " .previous \n" \
311 : "=r" (__pu_err) \
312 : "0" (0), "Jr" (__pu_val), "o" (__m(ptr)), \
313 "i" (-EFAULT)); \
314}
315
316#define __put_data_asm_ll32(insn, ptr) \
317{ \
318 __asm__ __volatile__( \
319 "1: "insn("%2", "(%3)")" # __put_data_asm_ll32 \n" \
320 "2: "insn("%D2", "4(%3)")" \n" \
321 "3: \n" \
322 " .insn \n" \
323 " .section .fixup,\"ax\" \n" \
324 "4: li %0, %4 \n" \
325 " j 3b \n" \
326 " .previous \n" \
327 " .section __ex_table,\"a\" \n" \
328 " " __UA_ADDR " 1b, 4b \n" \
329 " " __UA_ADDR " 2b, 4b \n" \
330 " .previous" \
331 : "=r" (__pu_err) \
332 : "0" (0), "r" (__pu_val), "r" (ptr), \
333 "i" (-EFAULT)); \
334}
335
336#define __put_kernel_nofault(dst, src, type, err_label) \
337do { \
338 type __pu_val; \
339 int __pu_err = 0; \
340 \
341 __pu_val = *(__force type *)(src); \
342 switch (sizeof(type)) { \
343 case 1: \
344 __put_data_asm(kernel_sb, (type *)(dst)); \
345 break; \
346 case 2: \
347 __put_data_asm(kernel_sh, (type *)(dst)); \
348 break; \
349 case 4: \
350 __put_data_asm(kernel_sw, (type *)(dst)) \
351 break; \
352 case 8: \
353 __PUT_DW(kernel_sd, (type *)(dst)); \
354 break; \
355 default: \
356 BUILD_BUG(); \
357 break; \
358 } \
359 if (unlikely(__pu_err)) \
360 goto err_label; \
361} while (0)
362
363
364/*
365 * We're generating jump to subroutines which will be outside the range of
366 * jump instructions
367 */
368#ifdef MODULE
369#define __MODULE_JAL(destination) \
370 ".set\tnoat\n\t" \
371 __UA_LA "\t$1, " #destination "\n\t" \
372 "jalr\t$1\n\t" \
373 ".set\tat\n\t"
374#else
375#define __MODULE_JAL(destination) \
376 "jal\t" #destination "\n\t"
377#endif
378
379#if defined(CONFIG_CPU_DADDI_WORKAROUNDS) || (defined(CONFIG_EVA) && \
380 defined(CONFIG_CPU_HAS_PREFETCH))
381#define DADDI_SCRATCH "$3"
382#else
383#define DADDI_SCRATCH "$0"
384#endif
385
386extern size_t __raw_copy_from_user(void *__to, const void *__from, size_t __n);
387extern size_t __raw_copy_to_user(void *__to, const void *__from, size_t __n);
388
389static inline unsigned long
390raw_copy_from_user(void *to, const void __user *from, unsigned long n)
391{
392 register void *__cu_to_r __asm__("$4");
393 register const void __user *__cu_from_r __asm__("$5");
394 register long __cu_len_r __asm__("$6");
395
396 __cu_to_r = to;
397 __cu_from_r = from;
398 __cu_len_r = n;
399
400 __asm__ __volatile__(
401 ".set\tnoreorder\n\t"
402 __MODULE_JAL(__raw_copy_from_user)
403 ".set\tnoat\n\t"
404 __UA_ADDU "\t$1, %1, %2\n\t"
405 ".set\tat\n\t"
406 ".set\treorder"
407 : "+r" (__cu_to_r), "+r" (__cu_from_r), "+r" (__cu_len_r)
408 :
409 : "$8", "$9", "$10", "$11", "$12", "$14", "$15", "$24", "$31",
410 DADDI_SCRATCH, "memory");
411
412 return __cu_len_r;
413}
414
415static inline unsigned long
416raw_copy_to_user(void __user *to, const void *from, unsigned long n)
417{
418 register void __user *__cu_to_r __asm__("$4");
419 register const void *__cu_from_r __asm__("$5");
420 register long __cu_len_r __asm__("$6");
421
422 __cu_to_r = (to);
423 __cu_from_r = (from);
424 __cu_len_r = (n);
425
426 __asm__ __volatile__(
427 __MODULE_JAL(__raw_copy_to_user)
428 : "+r" (__cu_to_r), "+r" (__cu_from_r), "+r" (__cu_len_r)
429 :
430 : "$8", "$9", "$10", "$11", "$12", "$14", "$15", "$24", "$31",
431 DADDI_SCRATCH, "memory");
432
433 return __cu_len_r;
434}
435
436#define INLINE_COPY_FROM_USER
437#define INLINE_COPY_TO_USER
438
439extern __kernel_size_t __bzero(void __user *addr, __kernel_size_t size);
440
441/*
442 * __clear_user: - Zero a block of memory in user space, with less checking.
443 * @to: Destination address, in user space.
444 * @n: Number of bytes to zero.
445 *
446 * Zero a block of memory in user space. Caller must check
447 * the specified block with access_ok() before calling this function.
448 *
449 * Returns number of bytes that could not be cleared.
450 * On success, this will be zero.
451 */
452static inline __kernel_size_t
453__clear_user(void __user *addr, __kernel_size_t size)
454{
455 __kernel_size_t res;
456
457#ifdef CONFIG_CPU_MICROMIPS
458/* micromips memset / bzero also clobbers t7 & t8 */
459#define bzero_clobbers "$4", "$5", "$6", __UA_t0, __UA_t1, "$15", "$24", "$31"
460#else
461#define bzero_clobbers "$4", "$5", "$6", __UA_t0, __UA_t1, "$31"
462#endif /* CONFIG_CPU_MICROMIPS */
463
464 might_fault();
465 __asm__ __volatile__(
466 "move\t$4, %1\n\t"
467 "move\t$5, $0\n\t"
468 "move\t$6, %2\n\t"
469 __MODULE_JAL(__bzero)
470 "move\t%0, $6"
471 : "=r" (res)
472 : "r" (addr), "r" (size)
473 : bzero_clobbers);
474
475 return res;
476}
477
478#define clear_user(addr,n) \
479({ \
480 void __user * __cl_addr = (addr); \
481 unsigned long __cl_size = (n); \
482 if (__cl_size && access_ok(__cl_addr, __cl_size)) \
483 __cl_size = __clear_user(__cl_addr, __cl_size); \
484 __cl_size; \
485})
486
487extern long __strncpy_from_user_asm(char *__to, const char __user *__from, long __len);
488
489/*
490 * strncpy_from_user: - Copy a NUL terminated string from userspace.
491 * @dst: Destination address, in kernel space. This buffer must be at
492 * least @count bytes long.
493 * @src: Source address, in user space.
494 * @count: Maximum number of bytes to copy, including the trailing NUL.
495 *
496 * Copies a NUL-terminated string from userspace to kernel space.
497 *
498 * On success, returns the length of the string (not including the trailing
499 * NUL).
500 *
501 * If access to userspace fails, returns -EFAULT (some data may have been
502 * copied).
503 *
504 * If @count is smaller than the length of the string, copies @count bytes
505 * and returns @count.
506 */
507static inline long
508strncpy_from_user(char *__to, const char __user *__from, long __len)
509{
510 long res;
511
512 if (!access_ok(__from, __len))
513 return -EFAULT;
514
515 might_fault();
516 __asm__ __volatile__(
517 "move\t$4, %1\n\t"
518 "move\t$5, %2\n\t"
519 "move\t$6, %3\n\t"
520 __MODULE_JAL(__strncpy_from_user_asm)
521 "move\t%0, $2"
522 : "=r" (res)
523 : "r" (__to), "r" (__from), "r" (__len)
524 : "$2", "$3", "$4", "$5", "$6", __UA_t0, "$31", "memory");
525
526 return res;
527}
528
529extern long __strnlen_user_asm(const char __user *s, long n);
530
531/*
532 * strnlen_user: - Get the size of a string in user space.
533 * @str: The string to measure.
534 *
535 * Context: User context only. This function may sleep if pagefaults are
536 * enabled.
537 *
538 * Get the size of a NUL-terminated string in user space.
539 *
540 * Returns the size of the string INCLUDING the terminating NUL.
541 * On exception, returns 0.
542 * If the string is too long, returns a value greater than @n.
543 */
544static inline long strnlen_user(const char __user *s, long n)
545{
546 long res;
547
548 if (!access_ok(s, 1))
549 return 0;
550
551 might_fault();
552 __asm__ __volatile__(
553 "move\t$4, %1\n\t"
554 "move\t$5, %2\n\t"
555 __MODULE_JAL(__strnlen_user_asm)
556 "move\t%0, $2"
557 : "=r" (res)
558 : "r" (s), "r" (n)
559 : "$2", "$4", "$5", __UA_t0, "$31");
560
561 return res;
562}
563
564#endif /* _ASM_UACCESS_H */
1/*
2 * This file is subject to the terms and conditions of the GNU General Public
3 * License. See the file "COPYING" in the main directory of this archive
4 * for more details.
5 *
6 * Copyright (C) 1996, 1997, 1998, 1999, 2000, 03, 04 by Ralf Baechle
7 * Copyright (C) 1999, 2000 Silicon Graphics, Inc.
8 * Copyright (C) 2007 Maciej W. Rozycki
9 */
10#ifndef _ASM_UACCESS_H
11#define _ASM_UACCESS_H
12
13#include <linux/kernel.h>
14#include <linux/errno.h>
15#include <linux/thread_info.h>
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#ifdef CONFIG_32BIT
25
26#define __UA_LIMIT 0x80000000UL
27
28#define __UA_ADDR ".word"
29#define __UA_LA "la"
30#define __UA_ADDU "addu"
31#define __UA_t0 "$8"
32#define __UA_t1 "$9"
33
34#endif /* CONFIG_32BIT */
35
36#ifdef CONFIG_64BIT
37
38extern u64 __ua_limit;
39
40#define __UA_LIMIT __ua_limit
41
42#define __UA_ADDR ".dword"
43#define __UA_LA "dla"
44#define __UA_ADDU "daddu"
45#define __UA_t0 "$12"
46#define __UA_t1 "$13"
47
48#endif /* CONFIG_64BIT */
49
50/*
51 * USER_DS is a bitmask that has the bits set that may not be set in a valid
52 * userspace address. Note that we limit 32-bit userspace to 0x7fff8000 but
53 * the arithmetic we're doing only works if the limit is a power of two, so
54 * we use 0x80000000 here on 32-bit kernels. If a process passes an invalid
55 * address in this range it's the process's problem, not ours :-)
56 */
57
58#define KERNEL_DS ((mm_segment_t) { 0UL })
59#define USER_DS ((mm_segment_t) { __UA_LIMIT })
60
61#define VERIFY_READ 0
62#define VERIFY_WRITE 1
63
64#define get_ds() (KERNEL_DS)
65#define get_fs() (current_thread_info()->addr_limit)
66#define set_fs(x) (current_thread_info()->addr_limit = (x))
67
68#define segment_eq(a, b) ((a).seg == (b).seg)
69
70
71/*
72 * Is a address valid? This does a straighforward calculation rather
73 * than tests.
74 *
75 * Address valid if:
76 * - "addr" doesn't have any high-bits set
77 * - AND "size" doesn't have any high-bits set
78 * - AND "addr+size" doesn't have any high-bits set
79 * - OR we are in kernel mode.
80 *
81 * __ua_size() is a trick to avoid runtime checking of positive constant
82 * sizes; for those we already know at compile time that the size is ok.
83 */
84#define __ua_size(size) \
85 ((__builtin_constant_p(size) && (signed long) (size) > 0) ? 0 : (size))
86
87/*
88 * access_ok: - Checks if a user space pointer is valid
89 * @type: Type of access: %VERIFY_READ or %VERIFY_WRITE. Note that
90 * %VERIFY_WRITE is a superset of %VERIFY_READ - if it is safe
91 * to write to a block, it is always safe to read from it.
92 * @addr: User space pointer to start of block to check
93 * @size: Size of block to check
94 *
95 * Context: User context only. This function may sleep.
96 *
97 * Checks if a pointer to a block of memory in user space is valid.
98 *
99 * Returns true (nonzero) if the memory block may be valid, false (zero)
100 * if it is definitely invalid.
101 *
102 * Note that, depending on architecture, this function probably just
103 * checks that the pointer is in the user space range - after calling
104 * this function, memory access functions may still return -EFAULT.
105 */
106
107#define __access_mask get_fs().seg
108
109#define __access_ok(addr, size, mask) \
110({ \
111 unsigned long __addr = (unsigned long) (addr); \
112 unsigned long __size = size; \
113 unsigned long __mask = mask; \
114 unsigned long __ok; \
115 \
116 __chk_user_ptr(addr); \
117 __ok = (signed long)(__mask & (__addr | (__addr + __size) | \
118 __ua_size(__size))); \
119 __ok == 0; \
120})
121
122#define access_ok(type, addr, size) \
123 likely(__access_ok((addr), (size), __access_mask))
124
125/*
126 * put_user: - Write a simple value into user space.
127 * @x: Value to copy to user space.
128 * @ptr: Destination address, in user space.
129 *
130 * Context: User context only. This function may sleep.
131 *
132 * This macro copies a single simple value from kernel space to user
133 * space. It supports simple types like char and int, but not larger
134 * data types like structures or arrays.
135 *
136 * @ptr must have pointer-to-simple-variable type, and @x must be assignable
137 * to the result of dereferencing @ptr.
138 *
139 * Returns zero on success, or -EFAULT on error.
140 */
141#define put_user(x,ptr) \
142 __put_user_check((x), (ptr), sizeof(*(ptr)))
143
144/*
145 * get_user: - Get a simple variable from user space.
146 * @x: Variable to store result.
147 * @ptr: Source address, in user space.
148 *
149 * Context: User context only. This function may sleep.
150 *
151 * This macro copies a single simple variable from user space to kernel
152 * space. It supports simple types like char and int, but not larger
153 * data types like structures or arrays.
154 *
155 * @ptr must have pointer-to-simple-variable type, and the result of
156 * dereferencing @ptr must be assignable to @x without a cast.
157 *
158 * Returns zero on success, or -EFAULT on error.
159 * On error, the variable @x is set to zero.
160 */
161#define get_user(x,ptr) \
162 __get_user_check((x), (ptr), sizeof(*(ptr)))
163
164/*
165 * __put_user: - Write a simple value into user space, with less checking.
166 * @x: Value to copy to user space.
167 * @ptr: Destination address, in user space.
168 *
169 * Context: User context only. This function may sleep.
170 *
171 * This macro copies a single simple value from kernel space to user
172 * space. It supports simple types like char and int, but not larger
173 * data types like structures or arrays.
174 *
175 * @ptr must have pointer-to-simple-variable type, and @x must be assignable
176 * to the result of dereferencing @ptr.
177 *
178 * Caller must check the pointer with access_ok() before calling this
179 * function.
180 *
181 * Returns zero on success, or -EFAULT on error.
182 */
183#define __put_user(x,ptr) \
184 __put_user_nocheck((x), (ptr), sizeof(*(ptr)))
185
186/*
187 * __get_user: - Get a simple variable from user space, with less checking.
188 * @x: Variable to store result.
189 * @ptr: Source address, in user space.
190 *
191 * Context: User context only. This function may sleep.
192 *
193 * This macro copies a single simple variable from user space to kernel
194 * space. It supports simple types like char and int, but not larger
195 * data types like structures or arrays.
196 *
197 * @ptr must have pointer-to-simple-variable type, and the result of
198 * dereferencing @ptr must be assignable to @x without a cast.
199 *
200 * Caller must check the pointer with access_ok() before calling this
201 * function.
202 *
203 * Returns zero on success, or -EFAULT on error.
204 * On error, the variable @x is set to zero.
205 */
206#define __get_user(x,ptr) \
207 __get_user_nocheck((x), (ptr), sizeof(*(ptr)))
208
209struct __large_struct { unsigned long buf[100]; };
210#define __m(x) (*(struct __large_struct __user *)(x))
211
212/*
213 * Yuck. We need two variants, one for 64bit operation and one
214 * for 32 bit mode and old iron.
215 */
216#ifdef CONFIG_32BIT
217#define __GET_USER_DW(val, ptr) __get_user_asm_ll32(val, ptr)
218#endif
219#ifdef CONFIG_64BIT
220#define __GET_USER_DW(val, ptr) __get_user_asm(val, "ld", ptr)
221#endif
222
223extern void __get_user_unknown(void);
224
225#define __get_user_common(val, size, ptr) \
226do { \
227 switch (size) { \
228 case 1: __get_user_asm(val, "lb", ptr); break; \
229 case 2: __get_user_asm(val, "lh", ptr); break; \
230 case 4: __get_user_asm(val, "lw", ptr); break; \
231 case 8: __GET_USER_DW(val, ptr); break; \
232 default: __get_user_unknown(); break; \
233 } \
234} while (0)
235
236#define __get_user_nocheck(x, ptr, size) \
237({ \
238 int __gu_err; \
239 \
240 __chk_user_ptr(ptr); \
241 __get_user_common((x), size, ptr); \
242 __gu_err; \
243})
244
245#define __get_user_check(x, ptr, size) \
246({ \
247 int __gu_err = -EFAULT; \
248 const __typeof__(*(ptr)) __user * __gu_ptr = (ptr); \
249 \
250 might_fault(); \
251 if (likely(access_ok(VERIFY_READ, __gu_ptr, size))) \
252 __get_user_common((x), size, __gu_ptr); \
253 \
254 __gu_err; \
255})
256
257#define __get_user_asm(val, insn, addr) \
258{ \
259 long __gu_tmp; \
260 \
261 __asm__ __volatile__( \
262 "1: " insn " %1, %3 \n" \
263 "2: \n" \
264 " .section .fixup,\"ax\" \n" \
265 "3: li %0, %4 \n" \
266 " j 2b \n" \
267 " .previous \n" \
268 " .section __ex_table,\"a\" \n" \
269 " "__UA_ADDR "\t1b, 3b \n" \
270 " .previous \n" \
271 : "=r" (__gu_err), "=r" (__gu_tmp) \
272 : "0" (0), "o" (__m(addr)), "i" (-EFAULT)); \
273 \
274 (val) = (__typeof__(*(addr))) __gu_tmp; \
275}
276
277/*
278 * Get a long long 64 using 32 bit registers.
279 */
280#define __get_user_asm_ll32(val, addr) \
281{ \
282 union { \
283 unsigned long long l; \
284 __typeof__(*(addr)) t; \
285 } __gu_tmp; \
286 \
287 __asm__ __volatile__( \
288 "1: lw %1, (%3) \n" \
289 "2: lw %D1, 4(%3) \n" \
290 "3: .section .fixup,\"ax\" \n" \
291 "4: li %0, %4 \n" \
292 " move %1, $0 \n" \
293 " move %D1, $0 \n" \
294 " j 3b \n" \
295 " .previous \n" \
296 " .section __ex_table,\"a\" \n" \
297 " " __UA_ADDR " 1b, 4b \n" \
298 " " __UA_ADDR " 2b, 4b \n" \
299 " .previous \n" \
300 : "=r" (__gu_err), "=&r" (__gu_tmp.l) \
301 : "0" (0), "r" (addr), "i" (-EFAULT)); \
302 \
303 (val) = __gu_tmp.t; \
304}
305
306/*
307 * Yuck. We need two variants, one for 64bit operation and one
308 * for 32 bit mode and old iron.
309 */
310#ifdef CONFIG_32BIT
311#define __PUT_USER_DW(ptr) __put_user_asm_ll32(ptr)
312#endif
313#ifdef CONFIG_64BIT
314#define __PUT_USER_DW(ptr) __put_user_asm("sd", ptr)
315#endif
316
317#define __put_user_nocheck(x, ptr, size) \
318({ \
319 __typeof__(*(ptr)) __pu_val; \
320 int __pu_err = 0; \
321 \
322 __chk_user_ptr(ptr); \
323 __pu_val = (x); \
324 switch (size) { \
325 case 1: __put_user_asm("sb", ptr); break; \
326 case 2: __put_user_asm("sh", ptr); break; \
327 case 4: __put_user_asm("sw", ptr); break; \
328 case 8: __PUT_USER_DW(ptr); break; \
329 default: __put_user_unknown(); break; \
330 } \
331 __pu_err; \
332})
333
334#define __put_user_check(x, ptr, size) \
335({ \
336 __typeof__(*(ptr)) __user *__pu_addr = (ptr); \
337 __typeof__(*(ptr)) __pu_val = (x); \
338 int __pu_err = -EFAULT; \
339 \
340 might_fault(); \
341 if (likely(access_ok(VERIFY_WRITE, __pu_addr, size))) { \
342 switch (size) { \
343 case 1: __put_user_asm("sb", __pu_addr); break; \
344 case 2: __put_user_asm("sh", __pu_addr); break; \
345 case 4: __put_user_asm("sw", __pu_addr); break; \
346 case 8: __PUT_USER_DW(__pu_addr); break; \
347 default: __put_user_unknown(); break; \
348 } \
349 } \
350 __pu_err; \
351})
352
353#define __put_user_asm(insn, ptr) \
354{ \
355 __asm__ __volatile__( \
356 "1: " insn " %z2, %3 # __put_user_asm\n" \
357 "2: \n" \
358 " .section .fixup,\"ax\" \n" \
359 "3: li %0, %4 \n" \
360 " j 2b \n" \
361 " .previous \n" \
362 " .section __ex_table,\"a\" \n" \
363 " " __UA_ADDR " 1b, 3b \n" \
364 " .previous \n" \
365 : "=r" (__pu_err) \
366 : "0" (0), "Jr" (__pu_val), "o" (__m(ptr)), \
367 "i" (-EFAULT)); \
368}
369
370#define __put_user_asm_ll32(ptr) \
371{ \
372 __asm__ __volatile__( \
373 "1: sw %2, (%3) # __put_user_asm_ll32 \n" \
374 "2: sw %D2, 4(%3) \n" \
375 "3: \n" \
376 " .section .fixup,\"ax\" \n" \
377 "4: li %0, %4 \n" \
378 " j 3b \n" \
379 " .previous \n" \
380 " .section __ex_table,\"a\" \n" \
381 " " __UA_ADDR " 1b, 4b \n" \
382 " " __UA_ADDR " 2b, 4b \n" \
383 " .previous" \
384 : "=r" (__pu_err) \
385 : "0" (0), "r" (__pu_val), "r" (ptr), \
386 "i" (-EFAULT)); \
387}
388
389extern void __put_user_unknown(void);
390
391/*
392 * put_user_unaligned: - Write a simple value into user space.
393 * @x: Value to copy to user space.
394 * @ptr: Destination address, in user space.
395 *
396 * Context: User context only. This function may sleep.
397 *
398 * This macro copies a single simple value from kernel space to user
399 * space. It supports simple types like char and int, but not larger
400 * data types like structures or arrays.
401 *
402 * @ptr must have pointer-to-simple-variable type, and @x must be assignable
403 * to the result of dereferencing @ptr.
404 *
405 * Returns zero on success, or -EFAULT on error.
406 */
407#define put_user_unaligned(x,ptr) \
408 __put_user_unaligned_check((x),(ptr),sizeof(*(ptr)))
409
410/*
411 * get_user_unaligned: - Get a simple variable from user space.
412 * @x: Variable to store result.
413 * @ptr: Source address, in user space.
414 *
415 * Context: User context only. This function may sleep.
416 *
417 * This macro copies a single simple variable from user space to kernel
418 * space. It supports simple types like char and int, but not larger
419 * data types like structures or arrays.
420 *
421 * @ptr must have pointer-to-simple-variable type, and the result of
422 * dereferencing @ptr must be assignable to @x without a cast.
423 *
424 * Returns zero on success, or -EFAULT on error.
425 * On error, the variable @x is set to zero.
426 */
427#define get_user_unaligned(x,ptr) \
428 __get_user_unaligned_check((x),(ptr),sizeof(*(ptr)))
429
430/*
431 * __put_user_unaligned: - Write a simple value into user space, with less checking.
432 * @x: Value to copy to user space.
433 * @ptr: Destination address, in user space.
434 *
435 * Context: User context only. This function may sleep.
436 *
437 * This macro copies a single simple value from kernel space to user
438 * space. It supports simple types like char and int, but not larger
439 * data types like structures or arrays.
440 *
441 * @ptr must have pointer-to-simple-variable type, and @x must be assignable
442 * to the result of dereferencing @ptr.
443 *
444 * Caller must check the pointer with access_ok() before calling this
445 * function.
446 *
447 * Returns zero on success, or -EFAULT on error.
448 */
449#define __put_user_unaligned(x,ptr) \
450 __put_user_unaligned_nocheck((x),(ptr),sizeof(*(ptr)))
451
452/*
453 * __get_user_unaligned: - Get a simple variable from user space, with less checking.
454 * @x: Variable to store result.
455 * @ptr: Source address, in user space.
456 *
457 * Context: User context only. This function may sleep.
458 *
459 * This macro copies a single simple variable from user space to kernel
460 * space. It supports simple types like char and int, but not larger
461 * data types like structures or arrays.
462 *
463 * @ptr must have pointer-to-simple-variable type, and the result of
464 * dereferencing @ptr must be assignable to @x without a cast.
465 *
466 * Caller must check the pointer with access_ok() before calling this
467 * function.
468 *
469 * Returns zero on success, or -EFAULT on error.
470 * On error, the variable @x is set to zero.
471 */
472#define __get_user_unaligned(x,ptr) \
473 __get_user__unalignednocheck((x),(ptr),sizeof(*(ptr)))
474
475/*
476 * Yuck. We need two variants, one for 64bit operation and one
477 * for 32 bit mode and old iron.
478 */
479#ifdef CONFIG_32BIT
480#define __GET_USER_UNALIGNED_DW(val, ptr) \
481 __get_user_unaligned_asm_ll32(val, ptr)
482#endif
483#ifdef CONFIG_64BIT
484#define __GET_USER_UNALIGNED_DW(val, ptr) \
485 __get_user_unaligned_asm(val, "uld", ptr)
486#endif
487
488extern void __get_user_unaligned_unknown(void);
489
490#define __get_user_unaligned_common(val, size, ptr) \
491do { \
492 switch (size) { \
493 case 1: __get_user_asm(val, "lb", ptr); break; \
494 case 2: __get_user_unaligned_asm(val, "ulh", ptr); break; \
495 case 4: __get_user_unaligned_asm(val, "ulw", ptr); break; \
496 case 8: __GET_USER_UNALIGNED_DW(val, ptr); break; \
497 default: __get_user_unaligned_unknown(); break; \
498 } \
499} while (0)
500
501#define __get_user_unaligned_nocheck(x,ptr,size) \
502({ \
503 int __gu_err; \
504 \
505 __get_user_unaligned_common((x), size, ptr); \
506 __gu_err; \
507})
508
509#define __get_user_unaligned_check(x,ptr,size) \
510({ \
511 int __gu_err = -EFAULT; \
512 const __typeof__(*(ptr)) __user * __gu_ptr = (ptr); \
513 \
514 if (likely(access_ok(VERIFY_READ, __gu_ptr, size))) \
515 __get_user_unaligned_common((x), size, __gu_ptr); \
516 \
517 __gu_err; \
518})
519
520#define __get_user_unaligned_asm(val, insn, addr) \
521{ \
522 long __gu_tmp; \
523 \
524 __asm__ __volatile__( \
525 "1: " insn " %1, %3 \n" \
526 "2: \n" \
527 " .section .fixup,\"ax\" \n" \
528 "3: li %0, %4 \n" \
529 " j 2b \n" \
530 " .previous \n" \
531 " .section __ex_table,\"a\" \n" \
532 " "__UA_ADDR "\t1b, 3b \n" \
533 " "__UA_ADDR "\t1b + 4, 3b \n" \
534 " .previous \n" \
535 : "=r" (__gu_err), "=r" (__gu_tmp) \
536 : "0" (0), "o" (__m(addr)), "i" (-EFAULT)); \
537 \
538 (val) = (__typeof__(*(addr))) __gu_tmp; \
539}
540
541/*
542 * Get a long long 64 using 32 bit registers.
543 */
544#define __get_user_unaligned_asm_ll32(val, addr) \
545{ \
546 unsigned long long __gu_tmp; \
547 \
548 __asm__ __volatile__( \
549 "1: ulw %1, (%3) \n" \
550 "2: ulw %D1, 4(%3) \n" \
551 " move %0, $0 \n" \
552 "3: .section .fixup,\"ax\" \n" \
553 "4: li %0, %4 \n" \
554 " move %1, $0 \n" \
555 " move %D1, $0 \n" \
556 " j 3b \n" \
557 " .previous \n" \
558 " .section __ex_table,\"a\" \n" \
559 " " __UA_ADDR " 1b, 4b \n" \
560 " " __UA_ADDR " 1b + 4, 4b \n" \
561 " " __UA_ADDR " 2b, 4b \n" \
562 " " __UA_ADDR " 2b + 4, 4b \n" \
563 " .previous \n" \
564 : "=r" (__gu_err), "=&r" (__gu_tmp) \
565 : "0" (0), "r" (addr), "i" (-EFAULT)); \
566 (val) = (__typeof__(*(addr))) __gu_tmp; \
567}
568
569/*
570 * Yuck. We need two variants, one for 64bit operation and one
571 * for 32 bit mode and old iron.
572 */
573#ifdef CONFIG_32BIT
574#define __PUT_USER_UNALIGNED_DW(ptr) __put_user_unaligned_asm_ll32(ptr)
575#endif
576#ifdef CONFIG_64BIT
577#define __PUT_USER_UNALIGNED_DW(ptr) __put_user_unaligned_asm("usd", ptr)
578#endif
579
580#define __put_user_unaligned_nocheck(x,ptr,size) \
581({ \
582 __typeof__(*(ptr)) __pu_val; \
583 int __pu_err = 0; \
584 \
585 __pu_val = (x); \
586 switch (size) { \
587 case 1: __put_user_asm("sb", ptr); break; \
588 case 2: __put_user_unaligned_asm("ush", ptr); break; \
589 case 4: __put_user_unaligned_asm("usw", ptr); break; \
590 case 8: __PUT_USER_UNALIGNED_DW(ptr); break; \
591 default: __put_user_unaligned_unknown(); break; \
592 } \
593 __pu_err; \
594})
595
596#define __put_user_unaligned_check(x,ptr,size) \
597({ \
598 __typeof__(*(ptr)) __user *__pu_addr = (ptr); \
599 __typeof__(*(ptr)) __pu_val = (x); \
600 int __pu_err = -EFAULT; \
601 \
602 if (likely(access_ok(VERIFY_WRITE, __pu_addr, size))) { \
603 switch (size) { \
604 case 1: __put_user_asm("sb", __pu_addr); break; \
605 case 2: __put_user_unaligned_asm("ush", __pu_addr); break; \
606 case 4: __put_user_unaligned_asm("usw", __pu_addr); break; \
607 case 8: __PUT_USER_UNALGINED_DW(__pu_addr); break; \
608 default: __put_user_unaligned_unknown(); break; \
609 } \
610 } \
611 __pu_err; \
612})
613
614#define __put_user_unaligned_asm(insn, ptr) \
615{ \
616 __asm__ __volatile__( \
617 "1: " insn " %z2, %3 # __put_user_unaligned_asm\n" \
618 "2: \n" \
619 " .section .fixup,\"ax\" \n" \
620 "3: li %0, %4 \n" \
621 " j 2b \n" \
622 " .previous \n" \
623 " .section __ex_table,\"a\" \n" \
624 " " __UA_ADDR " 1b, 3b \n" \
625 " .previous \n" \
626 : "=r" (__pu_err) \
627 : "0" (0), "Jr" (__pu_val), "o" (__m(ptr)), \
628 "i" (-EFAULT)); \
629}
630
631#define __put_user_unaligned_asm_ll32(ptr) \
632{ \
633 __asm__ __volatile__( \
634 "1: sw %2, (%3) # __put_user_unaligned_asm_ll32 \n" \
635 "2: sw %D2, 4(%3) \n" \
636 "3: \n" \
637 " .section .fixup,\"ax\" \n" \
638 "4: li %0, %4 \n" \
639 " j 3b \n" \
640 " .previous \n" \
641 " .section __ex_table,\"a\" \n" \
642 " " __UA_ADDR " 1b, 4b \n" \
643 " " __UA_ADDR " 1b + 4, 4b \n" \
644 " " __UA_ADDR " 2b, 4b \n" \
645 " " __UA_ADDR " 2b + 4, 4b \n" \
646 " .previous" \
647 : "=r" (__pu_err) \
648 : "0" (0), "r" (__pu_val), "r" (ptr), \
649 "i" (-EFAULT)); \
650}
651
652extern void __put_user_unaligned_unknown(void);
653
654/*
655 * We're generating jump to subroutines which will be outside the range of
656 * jump instructions
657 */
658#ifdef MODULE
659#define __MODULE_JAL(destination) \
660 ".set\tnoat\n\t" \
661 __UA_LA "\t$1, " #destination "\n\t" \
662 "jalr\t$1\n\t" \
663 ".set\tat\n\t"
664#else
665#define __MODULE_JAL(destination) \
666 "jal\t" #destination "\n\t"
667#endif
668
669#ifndef CONFIG_CPU_DADDI_WORKAROUNDS
670#define DADDI_SCRATCH "$0"
671#else
672#define DADDI_SCRATCH "$3"
673#endif
674
675extern size_t __copy_user(void *__to, const void *__from, size_t __n);
676
677#define __invoke_copy_to_user(to, from, n) \
678({ \
679 register void __user *__cu_to_r __asm__("$4"); \
680 register const void *__cu_from_r __asm__("$5"); \
681 register long __cu_len_r __asm__("$6"); \
682 \
683 __cu_to_r = (to); \
684 __cu_from_r = (from); \
685 __cu_len_r = (n); \
686 __asm__ __volatile__( \
687 __MODULE_JAL(__copy_user) \
688 : "+r" (__cu_to_r), "+r" (__cu_from_r), "+r" (__cu_len_r) \
689 : \
690 : "$8", "$9", "$10", "$11", "$12", "$15", "$24", "$31", \
691 DADDI_SCRATCH, "memory"); \
692 __cu_len_r; \
693})
694
695/*
696 * __copy_to_user: - Copy a block of data into user space, with less checking.
697 * @to: Destination address, in user space.
698 * @from: Source address, in kernel space.
699 * @n: Number of bytes to copy.
700 *
701 * Context: User context only. This function may sleep.
702 *
703 * Copy data from kernel space to user space. Caller must check
704 * the specified block with access_ok() before calling this function.
705 *
706 * Returns number of bytes that could not be copied.
707 * On success, this will be zero.
708 */
709#define __copy_to_user(to, from, n) \
710({ \
711 void __user *__cu_to; \
712 const void *__cu_from; \
713 long __cu_len; \
714 \
715 __cu_to = (to); \
716 __cu_from = (from); \
717 __cu_len = (n); \
718 might_fault(); \
719 __cu_len = __invoke_copy_to_user(__cu_to, __cu_from, __cu_len); \
720 __cu_len; \
721})
722
723extern size_t __copy_user_inatomic(void *__to, const void *__from, size_t __n);
724
725#define __copy_to_user_inatomic(to, from, n) \
726({ \
727 void __user *__cu_to; \
728 const void *__cu_from; \
729 long __cu_len; \
730 \
731 __cu_to = (to); \
732 __cu_from = (from); \
733 __cu_len = (n); \
734 __cu_len = __invoke_copy_to_user(__cu_to, __cu_from, __cu_len); \
735 __cu_len; \
736})
737
738#define __copy_from_user_inatomic(to, from, n) \
739({ \
740 void *__cu_to; \
741 const void __user *__cu_from; \
742 long __cu_len; \
743 \
744 __cu_to = (to); \
745 __cu_from = (from); \
746 __cu_len = (n); \
747 __cu_len = __invoke_copy_from_user_inatomic(__cu_to, __cu_from, \
748 __cu_len); \
749 __cu_len; \
750})
751
752/*
753 * copy_to_user: - Copy a block of data into user space.
754 * @to: Destination address, in user space.
755 * @from: Source address, in kernel space.
756 * @n: Number of bytes to copy.
757 *
758 * Context: User context only. This function may sleep.
759 *
760 * Copy data from kernel space to user space.
761 *
762 * Returns number of bytes that could not be copied.
763 * On success, this will be zero.
764 */
765#define copy_to_user(to, from, n) \
766({ \
767 void __user *__cu_to; \
768 const void *__cu_from; \
769 long __cu_len; \
770 \
771 __cu_to = (to); \
772 __cu_from = (from); \
773 __cu_len = (n); \
774 if (access_ok(VERIFY_WRITE, __cu_to, __cu_len)) { \
775 might_fault(); \
776 __cu_len = __invoke_copy_to_user(__cu_to, __cu_from, \
777 __cu_len); \
778 } \
779 __cu_len; \
780})
781
782#define __invoke_copy_from_user(to, from, n) \
783({ \
784 register void *__cu_to_r __asm__("$4"); \
785 register const void __user *__cu_from_r __asm__("$5"); \
786 register long __cu_len_r __asm__("$6"); \
787 \
788 __cu_to_r = (to); \
789 __cu_from_r = (from); \
790 __cu_len_r = (n); \
791 __asm__ __volatile__( \
792 ".set\tnoreorder\n\t" \
793 __MODULE_JAL(__copy_user) \
794 ".set\tnoat\n\t" \
795 __UA_ADDU "\t$1, %1, %2\n\t" \
796 ".set\tat\n\t" \
797 ".set\treorder" \
798 : "+r" (__cu_to_r), "+r" (__cu_from_r), "+r" (__cu_len_r) \
799 : \
800 : "$8", "$9", "$10", "$11", "$12", "$15", "$24", "$31", \
801 DADDI_SCRATCH, "memory"); \
802 __cu_len_r; \
803})
804
805#define __invoke_copy_from_user_inatomic(to, from, n) \
806({ \
807 register void *__cu_to_r __asm__("$4"); \
808 register const void __user *__cu_from_r __asm__("$5"); \
809 register long __cu_len_r __asm__("$6"); \
810 \
811 __cu_to_r = (to); \
812 __cu_from_r = (from); \
813 __cu_len_r = (n); \
814 __asm__ __volatile__( \
815 ".set\tnoreorder\n\t" \
816 __MODULE_JAL(__copy_user_inatomic) \
817 ".set\tnoat\n\t" \
818 __UA_ADDU "\t$1, %1, %2\n\t" \
819 ".set\tat\n\t" \
820 ".set\treorder" \
821 : "+r" (__cu_to_r), "+r" (__cu_from_r), "+r" (__cu_len_r) \
822 : \
823 : "$8", "$9", "$10", "$11", "$12", "$15", "$24", "$31", \
824 DADDI_SCRATCH, "memory"); \
825 __cu_len_r; \
826})
827
828/*
829 * __copy_from_user: - Copy a block of data from user space, with less checking.
830 * @to: Destination address, in kernel space.
831 * @from: Source address, in user space.
832 * @n: Number of bytes to copy.
833 *
834 * Context: User context only. This function may sleep.
835 *
836 * Copy data from user space to kernel space. Caller must check
837 * the specified block with access_ok() before calling this function.
838 *
839 * Returns number of bytes that could not be copied.
840 * On success, this will be zero.
841 *
842 * If some data could not be copied, this function will pad the copied
843 * data to the requested size using zero bytes.
844 */
845#define __copy_from_user(to, from, n) \
846({ \
847 void *__cu_to; \
848 const void __user *__cu_from; \
849 long __cu_len; \
850 \
851 __cu_to = (to); \
852 __cu_from = (from); \
853 __cu_len = (n); \
854 might_fault(); \
855 __cu_len = __invoke_copy_from_user(__cu_to, __cu_from, \
856 __cu_len); \
857 __cu_len; \
858})
859
860/*
861 * copy_from_user: - Copy a block of data from user space.
862 * @to: Destination address, in kernel space.
863 * @from: Source address, in user space.
864 * @n: Number of bytes to copy.
865 *
866 * Context: User context only. This function may sleep.
867 *
868 * Copy data from user space to kernel space.
869 *
870 * Returns number of bytes that could not be copied.
871 * On success, this will be zero.
872 *
873 * If some data could not be copied, this function will pad the copied
874 * data to the requested size using zero bytes.
875 */
876#define copy_from_user(to, from, n) \
877({ \
878 void *__cu_to; \
879 const void __user *__cu_from; \
880 long __cu_len; \
881 \
882 __cu_to = (to); \
883 __cu_from = (from); \
884 __cu_len = (n); \
885 if (access_ok(VERIFY_READ, __cu_from, __cu_len)) { \
886 might_fault(); \
887 __cu_len = __invoke_copy_from_user(__cu_to, __cu_from, \
888 __cu_len); \
889 } \
890 __cu_len; \
891})
892
893#define __copy_in_user(to, from, n) \
894({ \
895 void __user *__cu_to; \
896 const void __user *__cu_from; \
897 long __cu_len; \
898 \
899 __cu_to = (to); \
900 __cu_from = (from); \
901 __cu_len = (n); \
902 might_fault(); \
903 __cu_len = __invoke_copy_from_user(__cu_to, __cu_from, \
904 __cu_len); \
905 __cu_len; \
906})
907
908#define copy_in_user(to, from, n) \
909({ \
910 void __user *__cu_to; \
911 const void __user *__cu_from; \
912 long __cu_len; \
913 \
914 __cu_to = (to); \
915 __cu_from = (from); \
916 __cu_len = (n); \
917 if (likely(access_ok(VERIFY_READ, __cu_from, __cu_len) && \
918 access_ok(VERIFY_WRITE, __cu_to, __cu_len))) { \
919 might_fault(); \
920 __cu_len = __invoke_copy_from_user(__cu_to, __cu_from, \
921 __cu_len); \
922 } \
923 __cu_len; \
924})
925
926/*
927 * __clear_user: - Zero a block of memory in user space, with less checking.
928 * @to: Destination address, in user space.
929 * @n: Number of bytes to zero.
930 *
931 * Zero a block of memory in user space. Caller must check
932 * the specified block with access_ok() before calling this function.
933 *
934 * Returns number of bytes that could not be cleared.
935 * On success, this will be zero.
936 */
937static inline __kernel_size_t
938__clear_user(void __user *addr, __kernel_size_t size)
939{
940 __kernel_size_t res;
941
942 might_fault();
943 __asm__ __volatile__(
944 "move\t$4, %1\n\t"
945 "move\t$5, $0\n\t"
946 "move\t$6, %2\n\t"
947 __MODULE_JAL(__bzero)
948 "move\t%0, $6"
949 : "=r" (res)
950 : "r" (addr), "r" (size)
951 : "$4", "$5", "$6", __UA_t0, __UA_t1, "$31");
952
953 return res;
954}
955
956#define clear_user(addr,n) \
957({ \
958 void __user * __cl_addr = (addr); \
959 unsigned long __cl_size = (n); \
960 if (__cl_size && access_ok(VERIFY_WRITE, \
961 __cl_addr, __cl_size)) \
962 __cl_size = __clear_user(__cl_addr, __cl_size); \
963 __cl_size; \
964})
965
966/*
967 * __strncpy_from_user: - Copy a NUL terminated string from userspace, with less checking.
968 * @dst: Destination address, in kernel space. This buffer must be at
969 * least @count bytes long.
970 * @src: Source address, in user space.
971 * @count: Maximum number of bytes to copy, including the trailing NUL.
972 *
973 * Copies a NUL-terminated string from userspace to kernel space.
974 * Caller must check the specified block with access_ok() before calling
975 * this function.
976 *
977 * On success, returns the length of the string (not including the trailing
978 * NUL).
979 *
980 * If access to userspace fails, returns -EFAULT (some data may have been
981 * copied).
982 *
983 * If @count is smaller than the length of the string, copies @count bytes
984 * and returns @count.
985 */
986static inline long
987__strncpy_from_user(char *__to, const char __user *__from, long __len)
988{
989 long res;
990
991 might_fault();
992 __asm__ __volatile__(
993 "move\t$4, %1\n\t"
994 "move\t$5, %2\n\t"
995 "move\t$6, %3\n\t"
996 __MODULE_JAL(__strncpy_from_user_nocheck_asm)
997 "move\t%0, $2"
998 : "=r" (res)
999 : "r" (__to), "r" (__from), "r" (__len)
1000 : "$2", "$3", "$4", "$5", "$6", __UA_t0, "$31", "memory");
1001
1002 return res;
1003}
1004
1005/*
1006 * strncpy_from_user: - Copy a NUL terminated string from userspace.
1007 * @dst: Destination address, in kernel space. This buffer must be at
1008 * least @count bytes long.
1009 * @src: Source address, in user space.
1010 * @count: Maximum number of bytes to copy, including the trailing NUL.
1011 *
1012 * Copies a NUL-terminated string from userspace to kernel space.
1013 *
1014 * On success, returns the length of the string (not including the trailing
1015 * NUL).
1016 *
1017 * If access to userspace fails, returns -EFAULT (some data may have been
1018 * copied).
1019 *
1020 * If @count is smaller than the length of the string, copies @count bytes
1021 * and returns @count.
1022 */
1023static inline long
1024strncpy_from_user(char *__to, const char __user *__from, long __len)
1025{
1026 long res;
1027
1028 might_fault();
1029 __asm__ __volatile__(
1030 "move\t$4, %1\n\t"
1031 "move\t$5, %2\n\t"
1032 "move\t$6, %3\n\t"
1033 __MODULE_JAL(__strncpy_from_user_asm)
1034 "move\t%0, $2"
1035 : "=r" (res)
1036 : "r" (__to), "r" (__from), "r" (__len)
1037 : "$2", "$3", "$4", "$5", "$6", __UA_t0, "$31", "memory");
1038
1039 return res;
1040}
1041
1042/* Returns: 0 if bad, string length+1 (memory size) of string if ok */
1043static inline long __strlen_user(const char __user *s)
1044{
1045 long res;
1046
1047 might_fault();
1048 __asm__ __volatile__(
1049 "move\t$4, %1\n\t"
1050 __MODULE_JAL(__strlen_user_nocheck_asm)
1051 "move\t%0, $2"
1052 : "=r" (res)
1053 : "r" (s)
1054 : "$2", "$4", __UA_t0, "$31");
1055
1056 return res;
1057}
1058
1059/*
1060 * strlen_user: - Get the size of a string in user space.
1061 * @str: The string to measure.
1062 *
1063 * Context: User context only. This function may sleep.
1064 *
1065 * Get the size of a NUL-terminated string in user space.
1066 *
1067 * Returns the size of the string INCLUDING the terminating NUL.
1068 * On exception, returns 0.
1069 *
1070 * If there is a limit on the length of a valid string, you may wish to
1071 * consider using strnlen_user() instead.
1072 */
1073static inline long strlen_user(const char __user *s)
1074{
1075 long res;
1076
1077 might_fault();
1078 __asm__ __volatile__(
1079 "move\t$4, %1\n\t"
1080 __MODULE_JAL(__strlen_user_asm)
1081 "move\t%0, $2"
1082 : "=r" (res)
1083 : "r" (s)
1084 : "$2", "$4", __UA_t0, "$31");
1085
1086 return res;
1087}
1088
1089/* Returns: 0 if bad, string length+1 (memory size) of string if ok */
1090static inline long __strnlen_user(const char __user *s, long n)
1091{
1092 long res;
1093
1094 might_fault();
1095 __asm__ __volatile__(
1096 "move\t$4, %1\n\t"
1097 "move\t$5, %2\n\t"
1098 __MODULE_JAL(__strnlen_user_nocheck_asm)
1099 "move\t%0, $2"
1100 : "=r" (res)
1101 : "r" (s), "r" (n)
1102 : "$2", "$4", "$5", __UA_t0, "$31");
1103
1104 return res;
1105}
1106
1107/*
1108 * strlen_user: - Get the size of a string in user space.
1109 * @str: The string to measure.
1110 *
1111 * Context: User context only. This function may sleep.
1112 *
1113 * Get the size of a NUL-terminated string in user space.
1114 *
1115 * Returns the size of the string INCLUDING the terminating NUL.
1116 * On exception, returns 0.
1117 *
1118 * If there is a limit on the length of a valid string, you may wish to
1119 * consider using strnlen_user() instead.
1120 */
1121static inline long strnlen_user(const char __user *s, long n)
1122{
1123 long res;
1124
1125 might_fault();
1126 __asm__ __volatile__(
1127 "move\t$4, %1\n\t"
1128 "move\t$5, %2\n\t"
1129 __MODULE_JAL(__strnlen_user_asm)
1130 "move\t%0, $2"
1131 : "=r" (res)
1132 : "r" (s), "r" (n)
1133 : "$2", "$4", "$5", __UA_t0, "$31");
1134
1135 return res;
1136}
1137
1138struct exception_table_entry
1139{
1140 unsigned long insn;
1141 unsigned long nextinsn;
1142};
1143
1144extern int fixup_exception(struct pt_regs *regs);
1145
1146#endif /* _ASM_UACCESS_H */