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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 * 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
23#define __UA_ADDR ".word"
24#define __UA_LA "la"
25#define __UA_ADDU "addu"
26#define __UA_t0 "$8"
27#define __UA_t1 "$9"
28
29#endif /* CONFIG_32BIT */
30
31#ifdef CONFIG_64BIT
32
33extern u64 __ua_limit;
34
35#define __UA_LIMIT __ua_limit
36
37#define __UA_ADDR ".dword"
38#define __UA_LA "dla"
39#define __UA_ADDU "daddu"
40#define __UA_t0 "$12"
41#define __UA_t1 "$13"
42
43#endif /* CONFIG_64BIT */
44
45/*
46 * Is a address valid? This does a straightforward calculation rather
47 * than tests.
48 *
49 * Address valid if:
50 * - "addr" doesn't have any high-bits set
51 * - AND "size" doesn't have any high-bits set
52 * - AND "addr+size" doesn't have any high-bits set
53 * - OR we are in kernel mode.
54 *
55 * __ua_size() is a trick to avoid runtime checking of positive constant
56 * sizes; for those we already know at compile time that the size is ok.
57 */
58#define __ua_size(size) \
59 ((__builtin_constant_p(size) && (signed long) (size) > 0) ? 0 : (size))
60
61/*
62 * access_ok: - Checks if a user space pointer is valid
63 * @addr: User space pointer to start of block to check
64 * @size: Size of block to check
65 *
66 * Context: User context only. This function may sleep if pagefaults are
67 * enabled.
68 *
69 * Checks if a pointer to a block of memory in user space is valid.
70 *
71 * Returns true (nonzero) if the memory block may be valid, false (zero)
72 * if it is definitely invalid.
73 *
74 * Note that, depending on architecture, this function probably just
75 * checks that the pointer is in the user space range - after calling
76 * this function, memory access functions may still return -EFAULT.
77 */
78
79static inline int __access_ok(const void __user *p, unsigned long size)
80{
81 unsigned long addr = (unsigned long)p;
82 unsigned long end = addr + size - !!size;
83
84 return (__UA_LIMIT & (addr | end | __ua_size(size))) == 0;
85}
86
87#define access_ok(addr, size) \
88 likely(__access_ok((addr), (size)))
89
90/*
91 * put_user: - Write a simple value into user space.
92 * @x: Value to copy to user space.
93 * @ptr: Destination address, in user space.
94 *
95 * Context: User context only. This function may sleep if pagefaults are
96 * enabled.
97 *
98 * This macro copies a single simple value from kernel space to user
99 * space. It supports simple types like char and int, but not larger
100 * data types like structures or arrays.
101 *
102 * @ptr must have pointer-to-simple-variable type, and @x must be assignable
103 * to the result of dereferencing @ptr.
104 *
105 * Returns zero on success, or -EFAULT on error.
106 */
107#define put_user(x, ptr) \
108({ \
109 __typeof__(*(ptr)) __user *__p = (ptr); \
110 \
111 might_fault(); \
112 access_ok(__p, sizeof(*__p)) ? __put_user((x), __p) : -EFAULT; \
113})
114
115/*
116 * get_user: - Get a simple variable from user space.
117 * @x: Variable to store result.
118 * @ptr: Source address, in user space.
119 *
120 * Context: User context only. This function may sleep if pagefaults are
121 * enabled.
122 *
123 * This macro copies a single simple variable from user space to kernel
124 * space. It supports simple types like char and int, but not larger
125 * data types like structures or arrays.
126 *
127 * @ptr must have pointer-to-simple-variable type, and the result of
128 * dereferencing @ptr must be assignable to @x without a cast.
129 *
130 * Returns zero on success, or -EFAULT on error.
131 * On error, the variable @x is set to zero.
132 */
133#define get_user(x, ptr) \
134({ \
135 const __typeof__(*(ptr)) __user *__p = (ptr); \
136 \
137 might_fault(); \
138 access_ok(__p, sizeof(*__p)) ? __get_user((x), __p) : \
139 ((x) = 0, -EFAULT); \
140})
141
142/*
143 * __put_user: - Write a simple value into user space, with less checking.
144 * @x: Value to copy to user space.
145 * @ptr: Destination address, in user space.
146 *
147 * Context: User context only. This function may sleep if pagefaults are
148 * enabled.
149 *
150 * This macro copies a single simple value from kernel space to user
151 * space. It supports simple types like char and int, but not larger
152 * data types like structures or arrays.
153 *
154 * @ptr must have pointer-to-simple-variable type, and @x must be assignable
155 * to the result of dereferencing @ptr.
156 *
157 * Caller must check the pointer with access_ok() before calling this
158 * function.
159 *
160 * Returns zero on success, or -EFAULT on error.
161 */
162#define __put_user(x, ptr) \
163({ \
164 __typeof__(*(ptr)) __user *__pu_ptr = (ptr); \
165 __typeof__(*(ptr)) __pu_val = (x); \
166 int __pu_err = 0; \
167 \
168 __chk_user_ptr(__pu_ptr); \
169 switch (sizeof(*__pu_ptr)) { \
170 case 1: \
171 __put_data_asm(user_sb, __pu_ptr); \
172 break; \
173 case 2: \
174 __put_data_asm(user_sh, __pu_ptr); \
175 break; \
176 case 4: \
177 __put_data_asm(user_sw, __pu_ptr); \
178 break; \
179 case 8: \
180 __PUT_DW(user_sd, __pu_ptr); \
181 break; \
182 default: \
183 BUILD_BUG(); \
184 } \
185 \
186 __pu_err; \
187})
188
189/*
190 * __get_user: - Get a simple variable from user space, with less checking.
191 * @x: Variable to store result.
192 * @ptr: Source address, in user space.
193 *
194 * Context: User context only. This function may sleep if pagefaults are
195 * enabled.
196 *
197 * This macro copies a single simple variable from user space to kernel
198 * space. It supports simple types like char and int, but not larger
199 * data types like structures or arrays.
200 *
201 * @ptr must have pointer-to-simple-variable type, and the result of
202 * dereferencing @ptr must be assignable to @x without a cast.
203 *
204 * Caller must check the pointer with access_ok() before calling this
205 * function.
206 *
207 * Returns zero on success, or -EFAULT on error.
208 * On error, the variable @x is set to zero.
209 */
210#define __get_user(x, ptr) \
211({ \
212 const __typeof__(*(ptr)) __user *__gu_ptr = (ptr); \
213 int __gu_err = 0; \
214 \
215 __chk_user_ptr(__gu_ptr); \
216 switch (sizeof(*__gu_ptr)) { \
217 case 1: \
218 __get_data_asm((x), user_lb, __gu_ptr); \
219 break; \
220 case 2: \
221 __get_data_asm((x), user_lh, __gu_ptr); \
222 break; \
223 case 4: \
224 __get_data_asm((x), user_lw, __gu_ptr); \
225 break; \
226 case 8: \
227 __GET_DW((x), user_ld, __gu_ptr); \
228 break; \
229 default: \
230 BUILD_BUG(); \
231 } \
232 \
233 __gu_err; \
234})
235
236struct __large_struct { unsigned long buf[100]; };
237#define __m(x) (*(struct __large_struct __user *)(x))
238
239#ifdef CONFIG_32BIT
240#define __GET_DW(val, insn, ptr) __get_data_asm_ll32(val, insn, ptr)
241#endif
242#ifdef CONFIG_64BIT
243#define __GET_DW(val, insn, ptr) __get_data_asm(val, insn, ptr)
244#endif
245
246#define __get_data_asm(val, insn, addr) \
247{ \
248 long __gu_tmp; \
249 \
250 __asm__ __volatile__( \
251 "1: "insn("%1", "%3")" \n" \
252 "2: \n" \
253 " .insn \n" \
254 " .section .fixup,\"ax\" \n" \
255 "3: li %0, %4 \n" \
256 " move %1, $0 \n" \
257 " j 2b \n" \
258 " .previous \n" \
259 " .section __ex_table,\"a\" \n" \
260 " "__UA_ADDR "\t1b, 3b \n" \
261 " .previous \n" \
262 : "=r" (__gu_err), "=r" (__gu_tmp) \
263 : "0" (0), "o" (__m(addr)), "i" (-EFAULT)); \
264 \
265 (val) = (__typeof__(*(addr))) __gu_tmp; \
266}
267
268/*
269 * Get a long long 64 using 32 bit registers.
270 */
271#define __get_data_asm_ll32(val, insn, addr) \
272{ \
273 union { \
274 unsigned long long l; \
275 __typeof__(*(addr)) t; \
276 } __gu_tmp; \
277 \
278 __asm__ __volatile__( \
279 "1: " insn("%1", "(%3)")" \n" \
280 "2: " insn("%D1", "4(%3)")" \n" \
281 "3: \n" \
282 " .insn \n" \
283 " .section .fixup,\"ax\" \n" \
284 "4: li %0, %4 \n" \
285 " move %1, $0 \n" \
286 " move %D1, $0 \n" \
287 " j 3b \n" \
288 " .previous \n" \
289 " .section __ex_table,\"a\" \n" \
290 " " __UA_ADDR " 1b, 4b \n" \
291 " " __UA_ADDR " 2b, 4b \n" \
292 " .previous \n" \
293 : "=r" (__gu_err), "=&r" (__gu_tmp.l) \
294 : "0" (0), "r" (addr), "i" (-EFAULT)); \
295 \
296 (val) = __gu_tmp.t; \
297}
298
299#define HAVE_GET_KERNEL_NOFAULT
300
301#define __get_kernel_nofault(dst, src, type, err_label) \
302do { \
303 int __gu_err; \
304 \
305 switch (sizeof(type)) { \
306 case 1: \
307 __get_data_asm(*(type *)(dst), kernel_lb, \
308 (__force type *)(src)); \
309 break; \
310 case 2: \
311 __get_data_asm(*(type *)(dst), kernel_lh, \
312 (__force type *)(src)); \
313 break; \
314 case 4: \
315 __get_data_asm(*(type *)(dst), kernel_lw, \
316 (__force type *)(src)); \
317 break; \
318 case 8: \
319 __GET_DW(*(type *)(dst), kernel_ld, \
320 (__force type *)(src)); \
321 break; \
322 default: \
323 BUILD_BUG(); \
324 break; \
325 } \
326 if (unlikely(__gu_err)) \
327 goto err_label; \
328} while (0)
329
330/*
331 * Yuck. We need two variants, one for 64bit operation and one
332 * for 32 bit mode and old iron.
333 */
334#ifdef CONFIG_32BIT
335#define __PUT_DW(insn, ptr) __put_data_asm_ll32(insn, ptr)
336#endif
337#ifdef CONFIG_64BIT
338#define __PUT_DW(insn, ptr) __put_data_asm(insn, ptr)
339#endif
340
341#define __put_data_asm(insn, ptr) \
342{ \
343 __asm__ __volatile__( \
344 "1: "insn("%z2", "%3")" # __put_data_asm \n" \
345 "2: \n" \
346 " .insn \n" \
347 " .section .fixup,\"ax\" \n" \
348 "3: li %0, %4 \n" \
349 " j 2b \n" \
350 " .previous \n" \
351 " .section __ex_table,\"a\" \n" \
352 " " __UA_ADDR " 1b, 3b \n" \
353 " .previous \n" \
354 : "=r" (__pu_err) \
355 : "0" (0), "Jr" (__pu_val), "o" (__m(ptr)), \
356 "i" (-EFAULT)); \
357}
358
359#define __put_data_asm_ll32(insn, ptr) \
360{ \
361 __asm__ __volatile__( \
362 "1: "insn("%2", "(%3)")" # __put_data_asm_ll32 \n" \
363 "2: "insn("%D2", "4(%3)")" \n" \
364 "3: \n" \
365 " .insn \n" \
366 " .section .fixup,\"ax\" \n" \
367 "4: li %0, %4 \n" \
368 " j 3b \n" \
369 " .previous \n" \
370 " .section __ex_table,\"a\" \n" \
371 " " __UA_ADDR " 1b, 4b \n" \
372 " " __UA_ADDR " 2b, 4b \n" \
373 " .previous" \
374 : "=r" (__pu_err) \
375 : "0" (0), "r" (__pu_val), "r" (ptr), \
376 "i" (-EFAULT)); \
377}
378
379#define __put_kernel_nofault(dst, src, type, err_label) \
380do { \
381 type __pu_val; \
382 int __pu_err = 0; \
383 \
384 __pu_val = *(__force type *)(src); \
385 switch (sizeof(type)) { \
386 case 1: \
387 __put_data_asm(kernel_sb, (type *)(dst)); \
388 break; \
389 case 2: \
390 __put_data_asm(kernel_sh, (type *)(dst)); \
391 break; \
392 case 4: \
393 __put_data_asm(kernel_sw, (type *)(dst)) \
394 break; \
395 case 8: \
396 __PUT_DW(kernel_sd, (type *)(dst)); \
397 break; \
398 default: \
399 BUILD_BUG(); \
400 break; \
401 } \
402 if (unlikely(__pu_err)) \
403 goto err_label; \
404} while (0)
405
406
407/*
408 * We're generating jump to subroutines which will be outside the range of
409 * jump instructions
410 */
411#ifdef MODULE
412#define __MODULE_JAL(destination) \
413 ".set\tnoat\n\t" \
414 __UA_LA "\t$1, " #destination "\n\t" \
415 "jalr\t$1\n\t" \
416 ".set\tat\n\t"
417#else
418#define __MODULE_JAL(destination) \
419 "jal\t" #destination "\n\t"
420#endif
421
422#if defined(CONFIG_CPU_DADDI_WORKAROUNDS) || (defined(CONFIG_EVA) && \
423 defined(CONFIG_CPU_HAS_PREFETCH))
424#define DADDI_SCRATCH "$3"
425#else
426#define DADDI_SCRATCH "$0"
427#endif
428
429extern size_t __raw_copy_from_user(void *__to, const void *__from, size_t __n);
430extern size_t __raw_copy_to_user(void *__to, const void *__from, size_t __n);
431extern size_t __raw_copy_in_user(void *__to, const void *__from, size_t __n);
432
433static inline unsigned long
434raw_copy_from_user(void *to, const void __user *from, unsigned long n)
435{
436 register void *__cu_to_r __asm__("$4");
437 register const void __user *__cu_from_r __asm__("$5");
438 register long __cu_len_r __asm__("$6");
439
440 __cu_to_r = to;
441 __cu_from_r = from;
442 __cu_len_r = n;
443
444 __asm__ __volatile__(
445 ".set\tnoreorder\n\t"
446 __MODULE_JAL(__raw_copy_from_user)
447 ".set\tnoat\n\t"
448 __UA_ADDU "\t$1, %1, %2\n\t"
449 ".set\tat\n\t"
450 ".set\treorder"
451 : "+r" (__cu_to_r), "+r" (__cu_from_r), "+r" (__cu_len_r)
452 :
453 : "$8", "$9", "$10", "$11", "$12", "$14", "$15", "$24", "$31",
454 DADDI_SCRATCH, "memory");
455
456 return __cu_len_r;
457}
458
459static inline unsigned long
460raw_copy_to_user(void __user *to, const void *from, unsigned long n)
461{
462 register void __user *__cu_to_r __asm__("$4");
463 register const void *__cu_from_r __asm__("$5");
464 register long __cu_len_r __asm__("$6");
465
466 __cu_to_r = (to);
467 __cu_from_r = (from);
468 __cu_len_r = (n);
469
470 __asm__ __volatile__(
471 __MODULE_JAL(__raw_copy_to_user)
472 : "+r" (__cu_to_r), "+r" (__cu_from_r), "+r" (__cu_len_r)
473 :
474 : "$8", "$9", "$10", "$11", "$12", "$14", "$15", "$24", "$31",
475 DADDI_SCRATCH, "memory");
476
477 return __cu_len_r;
478}
479
480#define INLINE_COPY_FROM_USER
481#define INLINE_COPY_TO_USER
482
483static inline unsigned long
484raw_copy_in_user(void __user *to, const void __user *from, unsigned long n)
485{
486 register void __user *__cu_to_r __asm__("$4");
487 register const void __user *__cu_from_r __asm__("$5");
488 register long __cu_len_r __asm__("$6");
489
490 __cu_to_r = to;
491 __cu_from_r = from;
492 __cu_len_r = n;
493
494 __asm__ __volatile__(
495 ".set\tnoreorder\n\t"
496 __MODULE_JAL(__raw_copy_in_user)
497 ".set\tnoat\n\t"
498 __UA_ADDU "\t$1, %1, %2\n\t"
499 ".set\tat\n\t"
500 ".set\treorder"
501 : "+r" (__cu_to_r), "+r" (__cu_from_r), "+r" (__cu_len_r)
502 :
503 : "$8", "$9", "$10", "$11", "$12", "$14", "$15", "$24", "$31",
504 DADDI_SCRATCH, "memory");
505 return __cu_len_r;
506}
507
508extern __kernel_size_t __bzero(void __user *addr, __kernel_size_t size);
509
510/*
511 * __clear_user: - Zero a block of memory in user space, with less checking.
512 * @to: Destination address, in user space.
513 * @n: Number of bytes to zero.
514 *
515 * Zero a block of memory in user space. Caller must check
516 * the specified block with access_ok() before calling this function.
517 *
518 * Returns number of bytes that could not be cleared.
519 * On success, this will be zero.
520 */
521static inline __kernel_size_t
522__clear_user(void __user *addr, __kernel_size_t size)
523{
524 __kernel_size_t res;
525
526#ifdef CONFIG_CPU_MICROMIPS
527/* micromips memset / bzero also clobbers t7 & t8 */
528#define bzero_clobbers "$4", "$5", "$6", __UA_t0, __UA_t1, "$15", "$24", "$31"
529#else
530#define bzero_clobbers "$4", "$5", "$6", __UA_t0, __UA_t1, "$31"
531#endif /* CONFIG_CPU_MICROMIPS */
532
533 might_fault();
534 __asm__ __volatile__(
535 "move\t$4, %1\n\t"
536 "move\t$5, $0\n\t"
537 "move\t$6, %2\n\t"
538 __MODULE_JAL(__bzero)
539 "move\t%0, $6"
540 : "=r" (res)
541 : "r" (addr), "r" (size)
542 : bzero_clobbers);
543
544 return res;
545}
546
547#define clear_user(addr,n) \
548({ \
549 void __user * __cl_addr = (addr); \
550 unsigned long __cl_size = (n); \
551 if (__cl_size && access_ok(__cl_addr, __cl_size)) \
552 __cl_size = __clear_user(__cl_addr, __cl_size); \
553 __cl_size; \
554})
555
556extern long __strncpy_from_user_asm(char *__to, const char __user *__from, long __len);
557
558/*
559 * strncpy_from_user: - Copy a NUL terminated string from userspace.
560 * @dst: Destination address, in kernel space. This buffer must be at
561 * least @count bytes long.
562 * @src: Source address, in user space.
563 * @count: Maximum number of bytes to copy, including the trailing NUL.
564 *
565 * Copies a NUL-terminated string from userspace to kernel space.
566 *
567 * On success, returns the length of the string (not including the trailing
568 * NUL).
569 *
570 * If access to userspace fails, returns -EFAULT (some data may have been
571 * copied).
572 *
573 * If @count is smaller than the length of the string, copies @count bytes
574 * and returns @count.
575 */
576static inline long
577strncpy_from_user(char *__to, const char __user *__from, long __len)
578{
579 long res;
580
581 if (!access_ok(__from, __len))
582 return -EFAULT;
583
584 might_fault();
585 __asm__ __volatile__(
586 "move\t$4, %1\n\t"
587 "move\t$5, %2\n\t"
588 "move\t$6, %3\n\t"
589 __MODULE_JAL(__strncpy_from_user_asm)
590 "move\t%0, $2"
591 : "=r" (res)
592 : "r" (__to), "r" (__from), "r" (__len)
593 : "$2", "$3", "$4", "$5", "$6", __UA_t0, "$31", "memory");
594
595 return res;
596}
597
598extern long __strnlen_user_asm(const char __user *s, long n);
599
600/*
601 * strnlen_user: - Get the size of a string in user space.
602 * @str: The string to measure.
603 *
604 * Context: User context only. This function may sleep if pagefaults are
605 * enabled.
606 *
607 * Get the size of a NUL-terminated string in user space.
608 *
609 * Returns the size of the string INCLUDING the terminating NUL.
610 * On exception, returns 0.
611 * If the string is too long, returns a value greater than @n.
612 */
613static inline long strnlen_user(const char __user *s, long n)
614{
615 long res;
616
617 if (!access_ok(s, 1))
618 return 0;
619
620 might_fault();
621 __asm__ __volatile__(
622 "move\t$4, %1\n\t"
623 "move\t$5, %2\n\t"
624 __MODULE_JAL(__strnlen_user_asm)
625 "move\t%0, $2"
626 : "=r" (res)
627 : "r" (s), "r" (n)
628 : "$2", "$4", "$5", __UA_t0, "$31");
629
630 return res;
631}
632
633#endif /* _ASM_UACCESS_H */