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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/*
20 * The fs value determines whether argument validity checking should be
21 * performed or not. If get_fs() == USER_DS, checking is performed, with
22 * get_fs() == KERNEL_DS, checking is bypassed.
23 *
24 * For historical reasons, these macros are grossly misnamed.
25 */
26#ifdef CONFIG_32BIT
27
28#ifdef CONFIG_KVM_GUEST
29#define __UA_LIMIT 0x40000000UL
30#else
31#define __UA_LIMIT 0x80000000UL
32#endif
33
34#define __UA_ADDR ".word"
35#define __UA_LA "la"
36#define __UA_ADDU "addu"
37#define __UA_t0 "$8"
38#define __UA_t1 "$9"
39
40#endif /* CONFIG_32BIT */
41
42#ifdef CONFIG_64BIT
43
44extern u64 __ua_limit;
45
46#define __UA_LIMIT __ua_limit
47
48#define __UA_ADDR ".dword"
49#define __UA_LA "dla"
50#define __UA_ADDU "daddu"
51#define __UA_t0 "$12"
52#define __UA_t1 "$13"
53
54#endif /* CONFIG_64BIT */
55
56/*
57 * USER_DS is a bitmask that has the bits set that may not be set in a valid
58 * userspace address. Note that we limit 32-bit userspace to 0x7fff8000 but
59 * the arithmetic we're doing only works if the limit is a power of two, so
60 * we use 0x80000000 here on 32-bit kernels. If a process passes an invalid
61 * address in this range it's the process's problem, not ours :-)
62 */
63
64#ifdef CONFIG_KVM_GUEST
65#define KERNEL_DS ((mm_segment_t) { 0x80000000UL })
66#define USER_DS ((mm_segment_t) { 0xC0000000UL })
67#else
68#define KERNEL_DS ((mm_segment_t) { 0UL })
69#define USER_DS ((mm_segment_t) { __UA_LIMIT })
70#endif
71
72#define get_fs() (current_thread_info()->addr_limit)
73#define set_fs(x) (current_thread_info()->addr_limit = (x))
74
75#define segment_eq(a, b) ((a).seg == (b).seg)
76
77/*
78 * eva_kernel_access() - determine whether kernel memory access on an EVA system
79 *
80 * Determines whether memory accesses should be performed to kernel memory
81 * on a system using Extended Virtual Addressing (EVA).
82 *
83 * Return: true if a kernel memory access on an EVA system, else false.
84 */
85static inline bool eva_kernel_access(void)
86{
87 if (!IS_ENABLED(CONFIG_EVA))
88 return false;
89
90 return uaccess_kernel();
91}
92
93/*
94 * Is a address valid? This does a straightforward calculation rather
95 * than tests.
96 *
97 * Address valid if:
98 * - "addr" doesn't have any high-bits set
99 * - AND "size" doesn't have any high-bits set
100 * - AND "addr+size" doesn't have any high-bits set
101 * - OR we are in kernel mode.
102 *
103 * __ua_size() is a trick to avoid runtime checking of positive constant
104 * sizes; for those we already know at compile time that the size is ok.
105 */
106#define __ua_size(size) \
107 ((__builtin_constant_p(size) && (signed long) (size) > 0) ? 0 : (size))
108
109/*
110 * access_ok: - Checks if a user space pointer is valid
111 * @addr: User space pointer to start of block to check
112 * @size: Size of block to check
113 *
114 * Context: User context only. This function may sleep if pagefaults are
115 * enabled.
116 *
117 * Checks if a pointer to a block of memory in user space is valid.
118 *
119 * Returns true (nonzero) if the memory block may be valid, false (zero)
120 * if it is definitely invalid.
121 *
122 * Note that, depending on architecture, this function probably just
123 * checks that the pointer is in the user space range - after calling
124 * this function, memory access functions may still return -EFAULT.
125 */
126
127static inline int __access_ok(const void __user *p, unsigned long size)
128{
129 unsigned long addr = (unsigned long)p;
130 return (get_fs().seg & (addr | (addr + size) | __ua_size(size))) == 0;
131}
132
133#define access_ok(addr, size) \
134 likely(__access_ok((addr), (size)))
135
136/*
137 * put_user: - Write a simple value into user space.
138 * @x: Value to copy to user space.
139 * @ptr: Destination address, in user space.
140 *
141 * Context: User context only. This function may sleep if pagefaults are
142 * enabled.
143 *
144 * This macro copies a single simple value from kernel space to user
145 * space. It supports simple types like char and int, but not larger
146 * data types like structures or arrays.
147 *
148 * @ptr must have pointer-to-simple-variable type, and @x must be assignable
149 * to the result of dereferencing @ptr.
150 *
151 * Returns zero on success, or -EFAULT on error.
152 */
153#define put_user(x,ptr) \
154 __put_user_check((x), (ptr), sizeof(*(ptr)))
155
156/*
157 * get_user: - Get a simple variable from user space.
158 * @x: Variable to store result.
159 * @ptr: Source address, in user space.
160 *
161 * Context: User context only. This function may sleep if pagefaults are
162 * enabled.
163 *
164 * This macro copies a single simple variable from user space to kernel
165 * space. It supports simple types like char and int, but not larger
166 * data types like structures or arrays.
167 *
168 * @ptr must have pointer-to-simple-variable type, and the result of
169 * dereferencing @ptr must be assignable to @x without a cast.
170 *
171 * Returns zero on success, or -EFAULT on error.
172 * On error, the variable @x is set to zero.
173 */
174#define get_user(x,ptr) \
175 __get_user_check((x), (ptr), sizeof(*(ptr)))
176
177/*
178 * __put_user: - Write a simple value into user space, with less checking.
179 * @x: Value to copy to user space.
180 * @ptr: Destination address, in user space.
181 *
182 * Context: User context only. This function may sleep if pagefaults are
183 * enabled.
184 *
185 * This macro copies a single simple value from kernel space to user
186 * space. It supports simple types like char and int, but not larger
187 * data types like structures or arrays.
188 *
189 * @ptr must have pointer-to-simple-variable type, and @x must be assignable
190 * to the result of dereferencing @ptr.
191 *
192 * Caller must check the pointer with access_ok() before calling this
193 * function.
194 *
195 * Returns zero on success, or -EFAULT on error.
196 */
197#define __put_user(x,ptr) \
198 __put_user_nocheck((x), (ptr), sizeof(*(ptr)))
199
200/*
201 * __get_user: - Get a simple variable from user space, with less checking.
202 * @x: Variable to store result.
203 * @ptr: Source address, in user space.
204 *
205 * Context: User context only. This function may sleep if pagefaults are
206 * enabled.
207 *
208 * This macro copies a single simple variable from user space to kernel
209 * space. It supports simple types like char and int, but not larger
210 * data types like structures or arrays.
211 *
212 * @ptr must have pointer-to-simple-variable type, and the result of
213 * dereferencing @ptr must be assignable to @x without a cast.
214 *
215 * Caller must check the pointer with access_ok() before calling this
216 * function.
217 *
218 * Returns zero on success, or -EFAULT on error.
219 * On error, the variable @x is set to zero.
220 */
221#define __get_user(x,ptr) \
222 __get_user_nocheck((x), (ptr), sizeof(*(ptr)))
223
224struct __large_struct { unsigned long buf[100]; };
225#define __m(x) (*(struct __large_struct __user *)(x))
226
227/*
228 * Yuck. We need two variants, one for 64bit operation and one
229 * for 32 bit mode and old iron.
230 */
231#ifndef CONFIG_EVA
232#define __get_kernel_common(val, size, ptr) __get_user_common(val, size, ptr)
233#else
234/*
235 * Kernel specific functions for EVA. We need to use normal load instructions
236 * to read data from kernel when operating in EVA mode. We use these macros to
237 * avoid redefining __get_user_asm for EVA.
238 */
239#undef _loadd
240#undef _loadw
241#undef _loadh
242#undef _loadb
243#ifdef CONFIG_32BIT
244#define _loadd _loadw
245#else
246#define _loadd(reg, addr) "ld " reg ", " addr
247#endif
248#define _loadw(reg, addr) "lw " reg ", " addr
249#define _loadh(reg, addr) "lh " reg ", " addr
250#define _loadb(reg, addr) "lb " reg ", " addr
251
252#define __get_kernel_common(val, size, ptr) \
253do { \
254 switch (size) { \
255 case 1: __get_data_asm(val, _loadb, ptr); break; \
256 case 2: __get_data_asm(val, _loadh, ptr); break; \
257 case 4: __get_data_asm(val, _loadw, ptr); break; \
258 case 8: __GET_DW(val, _loadd, ptr); break; \
259 default: __get_user_unknown(); break; \
260 } \
261} while (0)
262#endif
263
264#ifdef CONFIG_32BIT
265#define __GET_DW(val, insn, ptr) __get_data_asm_ll32(val, insn, ptr)
266#endif
267#ifdef CONFIG_64BIT
268#define __GET_DW(val, insn, ptr) __get_data_asm(val, insn, ptr)
269#endif
270
271extern void __get_user_unknown(void);
272
273#define __get_user_common(val, size, ptr) \
274do { \
275 switch (size) { \
276 case 1: __get_data_asm(val, user_lb, ptr); break; \
277 case 2: __get_data_asm(val, user_lh, ptr); break; \
278 case 4: __get_data_asm(val, user_lw, ptr); break; \
279 case 8: __GET_DW(val, user_ld, ptr); break; \
280 default: __get_user_unknown(); break; \
281 } \
282} while (0)
283
284#define __get_user_nocheck(x, ptr, size) \
285({ \
286 int __gu_err; \
287 \
288 if (eva_kernel_access()) { \
289 __get_kernel_common((x), size, ptr); \
290 } else { \
291 __chk_user_ptr(ptr); \
292 __get_user_common((x), size, ptr); \
293 } \
294 __gu_err; \
295})
296
297#define __get_user_check(x, ptr, size) \
298({ \
299 int __gu_err = -EFAULT; \
300 const __typeof__(*(ptr)) __user * __gu_ptr = (ptr); \
301 \
302 might_fault(); \
303 if (likely(access_ok( __gu_ptr, size))) { \
304 if (eva_kernel_access()) \
305 __get_kernel_common((x), size, __gu_ptr); \
306 else \
307 __get_user_common((x), size, __gu_ptr); \
308 } else \
309 (x) = 0; \
310 \
311 __gu_err; \
312})
313
314#define __get_data_asm(val, insn, addr) \
315{ \
316 long __gu_tmp; \
317 \
318 __asm__ __volatile__( \
319 "1: "insn("%1", "%3")" \n" \
320 "2: \n" \
321 " .insn \n" \
322 " .section .fixup,\"ax\" \n" \
323 "3: li %0, %4 \n" \
324 " move %1, $0 \n" \
325 " j 2b \n" \
326 " .previous \n" \
327 " .section __ex_table,\"a\" \n" \
328 " "__UA_ADDR "\t1b, 3b \n" \
329 " .previous \n" \
330 : "=r" (__gu_err), "=r" (__gu_tmp) \
331 : "0" (0), "o" (__m(addr)), "i" (-EFAULT)); \
332 \
333 (val) = (__typeof__(*(addr))) __gu_tmp; \
334}
335
336/*
337 * Get a long long 64 using 32 bit registers.
338 */
339#define __get_data_asm_ll32(val, insn, addr) \
340{ \
341 union { \
342 unsigned long long l; \
343 __typeof__(*(addr)) t; \
344 } __gu_tmp; \
345 \
346 __asm__ __volatile__( \
347 "1: " insn("%1", "(%3)")" \n" \
348 "2: " insn("%D1", "4(%3)")" \n" \
349 "3: \n" \
350 " .insn \n" \
351 " .section .fixup,\"ax\" \n" \
352 "4: li %0, %4 \n" \
353 " move %1, $0 \n" \
354 " move %D1, $0 \n" \
355 " j 3b \n" \
356 " .previous \n" \
357 " .section __ex_table,\"a\" \n" \
358 " " __UA_ADDR " 1b, 4b \n" \
359 " " __UA_ADDR " 2b, 4b \n" \
360 " .previous \n" \
361 : "=r" (__gu_err), "=&r" (__gu_tmp.l) \
362 : "0" (0), "r" (addr), "i" (-EFAULT)); \
363 \
364 (val) = __gu_tmp.t; \
365}
366
367#ifndef CONFIG_EVA
368#define __put_kernel_common(ptr, size) __put_user_common(ptr, size)
369#else
370/*
371 * Kernel specific functions for EVA. We need to use normal load instructions
372 * to read data from kernel when operating in EVA mode. We use these macros to
373 * avoid redefining __get_data_asm for EVA.
374 */
375#undef _stored
376#undef _storew
377#undef _storeh
378#undef _storeb
379#ifdef CONFIG_32BIT
380#define _stored _storew
381#else
382#define _stored(reg, addr) "ld " reg ", " addr
383#endif
384
385#define _storew(reg, addr) "sw " reg ", " addr
386#define _storeh(reg, addr) "sh " reg ", " addr
387#define _storeb(reg, addr) "sb " reg ", " addr
388
389#define __put_kernel_common(ptr, size) \
390do { \
391 switch (size) { \
392 case 1: __put_data_asm(_storeb, ptr); break; \
393 case 2: __put_data_asm(_storeh, ptr); break; \
394 case 4: __put_data_asm(_storew, ptr); break; \
395 case 8: __PUT_DW(_stored, ptr); break; \
396 default: __put_user_unknown(); break; \
397 } \
398} while(0)
399#endif
400
401/*
402 * Yuck. We need two variants, one for 64bit operation and one
403 * for 32 bit mode and old iron.
404 */
405#ifdef CONFIG_32BIT
406#define __PUT_DW(insn, ptr) __put_data_asm_ll32(insn, ptr)
407#endif
408#ifdef CONFIG_64BIT
409#define __PUT_DW(insn, ptr) __put_data_asm(insn, ptr)
410#endif
411
412#define __put_user_common(ptr, size) \
413do { \
414 switch (size) { \
415 case 1: __put_data_asm(user_sb, ptr); break; \
416 case 2: __put_data_asm(user_sh, ptr); break; \
417 case 4: __put_data_asm(user_sw, ptr); break; \
418 case 8: __PUT_DW(user_sd, ptr); break; \
419 default: __put_user_unknown(); break; \
420 } \
421} while (0)
422
423#define __put_user_nocheck(x, ptr, size) \
424({ \
425 __typeof__(*(ptr)) __pu_val; \
426 int __pu_err = 0; \
427 \
428 __pu_val = (x); \
429 if (eva_kernel_access()) { \
430 __put_kernel_common(ptr, size); \
431 } else { \
432 __chk_user_ptr(ptr); \
433 __put_user_common(ptr, size); \
434 } \
435 __pu_err; \
436})
437
438#define __put_user_check(x, ptr, size) \
439({ \
440 __typeof__(*(ptr)) __user *__pu_addr = (ptr); \
441 __typeof__(*(ptr)) __pu_val = (x); \
442 int __pu_err = -EFAULT; \
443 \
444 might_fault(); \
445 if (likely(access_ok( __pu_addr, size))) { \
446 if (eva_kernel_access()) \
447 __put_kernel_common(__pu_addr, size); \
448 else \
449 __put_user_common(__pu_addr, size); \
450 } \
451 \
452 __pu_err; \
453})
454
455#define __put_data_asm(insn, ptr) \
456{ \
457 __asm__ __volatile__( \
458 "1: "insn("%z2", "%3")" # __put_data_asm \n" \
459 "2: \n" \
460 " .insn \n" \
461 " .section .fixup,\"ax\" \n" \
462 "3: li %0, %4 \n" \
463 " j 2b \n" \
464 " .previous \n" \
465 " .section __ex_table,\"a\" \n" \
466 " " __UA_ADDR " 1b, 3b \n" \
467 " .previous \n" \
468 : "=r" (__pu_err) \
469 : "0" (0), "Jr" (__pu_val), "o" (__m(ptr)), \
470 "i" (-EFAULT)); \
471}
472
473#define __put_data_asm_ll32(insn, ptr) \
474{ \
475 __asm__ __volatile__( \
476 "1: "insn("%2", "(%3)")" # __put_data_asm_ll32 \n" \
477 "2: "insn("%D2", "4(%3)")" \n" \
478 "3: \n" \
479 " .insn \n" \
480 " .section .fixup,\"ax\" \n" \
481 "4: li %0, %4 \n" \
482 " j 3b \n" \
483 " .previous \n" \
484 " .section __ex_table,\"a\" \n" \
485 " " __UA_ADDR " 1b, 4b \n" \
486 " " __UA_ADDR " 2b, 4b \n" \
487 " .previous" \
488 : "=r" (__pu_err) \
489 : "0" (0), "r" (__pu_val), "r" (ptr), \
490 "i" (-EFAULT)); \
491}
492
493extern void __put_user_unknown(void);
494
495/*
496 * We're generating jump to subroutines which will be outside the range of
497 * jump instructions
498 */
499#ifdef MODULE
500#define __MODULE_JAL(destination) \
501 ".set\tnoat\n\t" \
502 __UA_LA "\t$1, " #destination "\n\t" \
503 "jalr\t$1\n\t" \
504 ".set\tat\n\t"
505#else
506#define __MODULE_JAL(destination) \
507 "jal\t" #destination "\n\t"
508#endif
509
510#if defined(CONFIG_CPU_DADDI_WORKAROUNDS) || (defined(CONFIG_EVA) && \
511 defined(CONFIG_CPU_HAS_PREFETCH))
512#define DADDI_SCRATCH "$3"
513#else
514#define DADDI_SCRATCH "$0"
515#endif
516
517extern size_t __copy_user(void *__to, const void *__from, size_t __n);
518
519#define __invoke_copy_from(func, to, from, n) \
520({ \
521 register void *__cu_to_r __asm__("$4"); \
522 register const void __user *__cu_from_r __asm__("$5"); \
523 register long __cu_len_r __asm__("$6"); \
524 \
525 __cu_to_r = (to); \
526 __cu_from_r = (from); \
527 __cu_len_r = (n); \
528 __asm__ __volatile__( \
529 ".set\tnoreorder\n\t" \
530 __MODULE_JAL(func) \
531 ".set\tnoat\n\t" \
532 __UA_ADDU "\t$1, %1, %2\n\t" \
533 ".set\tat\n\t" \
534 ".set\treorder" \
535 : "+r" (__cu_to_r), "+r" (__cu_from_r), "+r" (__cu_len_r) \
536 : \
537 : "$8", "$9", "$10", "$11", "$12", "$14", "$15", "$24", "$31", \
538 DADDI_SCRATCH, "memory"); \
539 __cu_len_r; \
540})
541
542#define __invoke_copy_to(func, to, from, n) \
543({ \
544 register void __user *__cu_to_r __asm__("$4"); \
545 register const void *__cu_from_r __asm__("$5"); \
546 register long __cu_len_r __asm__("$6"); \
547 \
548 __cu_to_r = (to); \
549 __cu_from_r = (from); \
550 __cu_len_r = (n); \
551 __asm__ __volatile__( \
552 __MODULE_JAL(func) \
553 : "+r" (__cu_to_r), "+r" (__cu_from_r), "+r" (__cu_len_r) \
554 : \
555 : "$8", "$9", "$10", "$11", "$12", "$14", "$15", "$24", "$31", \
556 DADDI_SCRATCH, "memory"); \
557 __cu_len_r; \
558})
559
560#define __invoke_copy_from_kernel(to, from, n) \
561 __invoke_copy_from(__copy_user, to, from, n)
562
563#define __invoke_copy_to_kernel(to, from, n) \
564 __invoke_copy_to(__copy_user, to, from, n)
565
566#define ___invoke_copy_in_kernel(to, from, n) \
567 __invoke_copy_from(__copy_user, to, from, n)
568
569#ifndef CONFIG_EVA
570#define __invoke_copy_from_user(to, from, n) \
571 __invoke_copy_from(__copy_user, to, from, n)
572
573#define __invoke_copy_to_user(to, from, n) \
574 __invoke_copy_to(__copy_user, to, from, n)
575
576#define ___invoke_copy_in_user(to, from, n) \
577 __invoke_copy_from(__copy_user, to, from, n)
578
579#else
580
581/* EVA specific functions */
582
583extern size_t __copy_from_user_eva(void *__to, const void *__from,
584 size_t __n);
585extern size_t __copy_to_user_eva(void *__to, const void *__from,
586 size_t __n);
587extern size_t __copy_in_user_eva(void *__to, const void *__from, size_t __n);
588
589/*
590 * Source or destination address is in userland. We need to go through
591 * the TLB
592 */
593#define __invoke_copy_from_user(to, from, n) \
594 __invoke_copy_from(__copy_from_user_eva, to, from, n)
595
596#define __invoke_copy_to_user(to, from, n) \
597 __invoke_copy_to(__copy_to_user_eva, to, from, n)
598
599#define ___invoke_copy_in_user(to, from, n) \
600 __invoke_copy_from(__copy_in_user_eva, to, from, n)
601
602#endif /* CONFIG_EVA */
603
604static inline unsigned long
605raw_copy_to_user(void __user *to, const void *from, unsigned long n)
606{
607 if (eva_kernel_access())
608 return __invoke_copy_to_kernel(to, from, n);
609 else
610 return __invoke_copy_to_user(to, from, n);
611}
612
613static inline unsigned long
614raw_copy_from_user(void *to, const void __user *from, unsigned long n)
615{
616 if (eva_kernel_access())
617 return __invoke_copy_from_kernel(to, from, n);
618 else
619 return __invoke_copy_from_user(to, from, n);
620}
621
622#define INLINE_COPY_FROM_USER
623#define INLINE_COPY_TO_USER
624
625static inline unsigned long
626raw_copy_in_user(void __user*to, const void __user *from, unsigned long n)
627{
628 if (eva_kernel_access())
629 return ___invoke_copy_in_kernel(to, from, n);
630 else
631 return ___invoke_copy_in_user(to, from, n);
632}
633
634extern __kernel_size_t __bzero_kernel(void __user *addr, __kernel_size_t size);
635extern __kernel_size_t __bzero(void __user *addr, __kernel_size_t size);
636
637/*
638 * __clear_user: - Zero a block of memory in user space, with less checking.
639 * @to: Destination address, in user space.
640 * @n: Number of bytes to zero.
641 *
642 * Zero a block of memory in user space. Caller must check
643 * the specified block with access_ok() before calling this function.
644 *
645 * Returns number of bytes that could not be cleared.
646 * On success, this will be zero.
647 */
648static inline __kernel_size_t
649__clear_user(void __user *addr, __kernel_size_t size)
650{
651 __kernel_size_t res;
652
653#ifdef CONFIG_CPU_MICROMIPS
654/* micromips memset / bzero also clobbers t7 & t8 */
655#define bzero_clobbers "$4", "$5", "$6", __UA_t0, __UA_t1, "$15", "$24", "$31"
656#else
657#define bzero_clobbers "$4", "$5", "$6", __UA_t0, __UA_t1, "$31"
658#endif /* CONFIG_CPU_MICROMIPS */
659
660 if (eva_kernel_access()) {
661 __asm__ __volatile__(
662 "move\t$4, %1\n\t"
663 "move\t$5, $0\n\t"
664 "move\t$6, %2\n\t"
665 __MODULE_JAL(__bzero_kernel)
666 "move\t%0, $6"
667 : "=r" (res)
668 : "r" (addr), "r" (size)
669 : bzero_clobbers);
670 } else {
671 might_fault();
672 __asm__ __volatile__(
673 "move\t$4, %1\n\t"
674 "move\t$5, $0\n\t"
675 "move\t$6, %2\n\t"
676 __MODULE_JAL(__bzero)
677 "move\t%0, $6"
678 : "=r" (res)
679 : "r" (addr), "r" (size)
680 : bzero_clobbers);
681 }
682
683 return res;
684}
685
686#define clear_user(addr,n) \
687({ \
688 void __user * __cl_addr = (addr); \
689 unsigned long __cl_size = (n); \
690 if (__cl_size && access_ok(__cl_addr, __cl_size)) \
691 __cl_size = __clear_user(__cl_addr, __cl_size); \
692 __cl_size; \
693})
694
695extern long __strncpy_from_kernel_asm(char *__to, const char __user *__from, long __len);
696extern long __strncpy_from_user_asm(char *__to, const char __user *__from, long __len);
697
698/*
699 * strncpy_from_user: - Copy a NUL terminated string from userspace.
700 * @dst: Destination address, in kernel space. This buffer must be at
701 * least @count bytes long.
702 * @src: Source address, in user space.
703 * @count: Maximum number of bytes to copy, including the trailing NUL.
704 *
705 * Copies a NUL-terminated string from userspace to kernel space.
706 *
707 * On success, returns the length of the string (not including the trailing
708 * NUL).
709 *
710 * If access to userspace fails, returns -EFAULT (some data may have been
711 * copied).
712 *
713 * If @count is smaller than the length of the string, copies @count bytes
714 * and returns @count.
715 */
716static inline long
717strncpy_from_user(char *__to, const char __user *__from, long __len)
718{
719 long res;
720
721 if (eva_kernel_access()) {
722 __asm__ __volatile__(
723 "move\t$4, %1\n\t"
724 "move\t$5, %2\n\t"
725 "move\t$6, %3\n\t"
726 __MODULE_JAL(__strncpy_from_kernel_asm)
727 "move\t%0, $2"
728 : "=r" (res)
729 : "r" (__to), "r" (__from), "r" (__len)
730 : "$2", "$3", "$4", "$5", "$6", __UA_t0, "$31", "memory");
731 } else {
732 might_fault();
733 __asm__ __volatile__(
734 "move\t$4, %1\n\t"
735 "move\t$5, %2\n\t"
736 "move\t$6, %3\n\t"
737 __MODULE_JAL(__strncpy_from_user_asm)
738 "move\t%0, $2"
739 : "=r" (res)
740 : "r" (__to), "r" (__from), "r" (__len)
741 : "$2", "$3", "$4", "$5", "$6", __UA_t0, "$31", "memory");
742 }
743
744 return res;
745}
746
747extern long __strnlen_kernel_asm(const char __user *s, long n);
748extern long __strnlen_user_asm(const char __user *s, long n);
749
750/*
751 * strnlen_user: - Get the size of a string in user space.
752 * @str: The string to measure.
753 *
754 * Context: User context only. This function may sleep if pagefaults are
755 * enabled.
756 *
757 * Get the size of a NUL-terminated string in user space.
758 *
759 * Returns the size of the string INCLUDING the terminating NUL.
760 * On exception, returns 0.
761 * If the string is too long, returns a value greater than @n.
762 */
763static inline long strnlen_user(const char __user *s, long n)
764{
765 long res;
766
767 might_fault();
768 if (eva_kernel_access()) {
769 __asm__ __volatile__(
770 "move\t$4, %1\n\t"
771 "move\t$5, %2\n\t"
772 __MODULE_JAL(__strnlen_kernel_asm)
773 "move\t%0, $2"
774 : "=r" (res)
775 : "r" (s), "r" (n)
776 : "$2", "$4", "$5", __UA_t0, "$31");
777 } else {
778 __asm__ __volatile__(
779 "move\t$4, %1\n\t"
780 "move\t$5, %2\n\t"
781 __MODULE_JAL(__strnlen_user_asm)
782 "move\t%0, $2"
783 : "=r" (res)
784 : "r" (s), "r" (n)
785 : "$2", "$4", "$5", __UA_t0, "$31");
786 }
787
788 return res;
789}
790
791#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/errno.h>
16#include <linux/thread_info.h>
17#include <asm/asm-eva.h>
18
19/*
20 * The fs value determines whether argument validity checking should be
21 * performed or not. If get_fs() == USER_DS, checking is performed, with
22 * get_fs() == KERNEL_DS, checking is bypassed.
23 *
24 * For historical reasons, these macros are grossly misnamed.
25 */
26#ifdef CONFIG_32BIT
27
28#ifdef CONFIG_KVM_GUEST
29#define __UA_LIMIT 0x40000000UL
30#else
31#define __UA_LIMIT 0x80000000UL
32#endif
33
34#define __UA_ADDR ".word"
35#define __UA_LA "la"
36#define __UA_ADDU "addu"
37#define __UA_t0 "$8"
38#define __UA_t1 "$9"
39
40#endif /* CONFIG_32BIT */
41
42#ifdef CONFIG_64BIT
43
44extern u64 __ua_limit;
45
46#define __UA_LIMIT __ua_limit
47
48#define __UA_ADDR ".dword"
49#define __UA_LA "dla"
50#define __UA_ADDU "daddu"
51#define __UA_t0 "$12"
52#define __UA_t1 "$13"
53
54#endif /* CONFIG_64BIT */
55
56/*
57 * USER_DS is a bitmask that has the bits set that may not be set in a valid
58 * userspace address. Note that we limit 32-bit userspace to 0x7fff8000 but
59 * the arithmetic we're doing only works if the limit is a power of two, so
60 * we use 0x80000000 here on 32-bit kernels. If a process passes an invalid
61 * address in this range it's the process's problem, not ours :-)
62 */
63
64#ifdef CONFIG_KVM_GUEST
65#define KERNEL_DS ((mm_segment_t) { 0x80000000UL })
66#define USER_DS ((mm_segment_t) { 0xC0000000UL })
67#else
68#define KERNEL_DS ((mm_segment_t) { 0UL })
69#define USER_DS ((mm_segment_t) { __UA_LIMIT })
70#endif
71
72#define VERIFY_READ 0
73#define VERIFY_WRITE 1
74
75#define get_ds() (KERNEL_DS)
76#define get_fs() (current_thread_info()->addr_limit)
77#define set_fs(x) (current_thread_info()->addr_limit = (x))
78
79#define segment_eq(a, b) ((a).seg == (b).seg)
80
81
82/*
83 * Is a address valid? This does a straighforward calculation rather
84 * than tests.
85 *
86 * Address valid if:
87 * - "addr" doesn't have any high-bits set
88 * - AND "size" doesn't have any high-bits set
89 * - AND "addr+size" doesn't have any high-bits set
90 * - OR we are in kernel mode.
91 *
92 * __ua_size() is a trick to avoid runtime checking of positive constant
93 * sizes; for those we already know at compile time that the size is ok.
94 */
95#define __ua_size(size) \
96 ((__builtin_constant_p(size) && (signed long) (size) > 0) ? 0 : (size))
97
98/*
99 * access_ok: - Checks if a user space pointer is valid
100 * @type: Type of access: %VERIFY_READ or %VERIFY_WRITE. Note that
101 * %VERIFY_WRITE is a superset of %VERIFY_READ - if it is safe
102 * to write to a block, it is always safe to read from it.
103 * @addr: User space pointer to start of block to check
104 * @size: Size of block to check
105 *
106 * Context: User context only. This function may sleep.
107 *
108 * Checks if a pointer to a block of memory in user space is valid.
109 *
110 * Returns true (nonzero) if the memory block may be valid, false (zero)
111 * if it is definitely invalid.
112 *
113 * Note that, depending on architecture, this function probably just
114 * checks that the pointer is in the user space range - after calling
115 * this function, memory access functions may still return -EFAULT.
116 */
117
118#define __access_mask get_fs().seg
119
120#define __access_ok(addr, size, mask) \
121({ \
122 unsigned long __addr = (unsigned long) (addr); \
123 unsigned long __size = size; \
124 unsigned long __mask = mask; \
125 unsigned long __ok; \
126 \
127 __chk_user_ptr(addr); \
128 __ok = (signed long)(__mask & (__addr | (__addr + __size) | \
129 __ua_size(__size))); \
130 __ok == 0; \
131})
132
133#define access_ok(type, addr, size) \
134 likely(__access_ok((addr), (size), __access_mask))
135
136/*
137 * put_user: - Write a simple value into user space.
138 * @x: Value to copy to user space.
139 * @ptr: Destination address, in user space.
140 *
141 * Context: User context only. This function may sleep.
142 *
143 * This macro copies a single simple value from kernel space to user
144 * space. It supports simple types like char and int, but not larger
145 * data types like structures or arrays.
146 *
147 * @ptr must have pointer-to-simple-variable type, and @x must be assignable
148 * to the result of dereferencing @ptr.
149 *
150 * Returns zero on success, or -EFAULT on error.
151 */
152#define put_user(x,ptr) \
153 __put_user_check((x), (ptr), sizeof(*(ptr)))
154
155/*
156 * get_user: - Get a simple variable from user space.
157 * @x: Variable to store result.
158 * @ptr: Source address, in user space.
159 *
160 * Context: User context only. This function may sleep.
161 *
162 * This macro copies a single simple variable from user space to kernel
163 * space. It supports simple types like char and int, but not larger
164 * data types like structures or arrays.
165 *
166 * @ptr must have pointer-to-simple-variable type, and the result of
167 * dereferencing @ptr must be assignable to @x without a cast.
168 *
169 * Returns zero on success, or -EFAULT on error.
170 * On error, the variable @x is set to zero.
171 */
172#define get_user(x,ptr) \
173 __get_user_check((x), (ptr), sizeof(*(ptr)))
174
175/*
176 * __put_user: - Write a simple value into user space, with less checking.
177 * @x: Value to copy to user space.
178 * @ptr: Destination address, in user space.
179 *
180 * Context: User context only. This function may sleep.
181 *
182 * This macro copies a single simple value from kernel space to user
183 * space. It supports simple types like char and int, but not larger
184 * data types like structures or arrays.
185 *
186 * @ptr must have pointer-to-simple-variable type, and @x must be assignable
187 * to the result of dereferencing @ptr.
188 *
189 * Caller must check the pointer with access_ok() before calling this
190 * function.
191 *
192 * Returns zero on success, or -EFAULT on error.
193 */
194#define __put_user(x,ptr) \
195 __put_user_nocheck((x), (ptr), sizeof(*(ptr)))
196
197/*
198 * __get_user: - Get a simple variable from user space, with less checking.
199 * @x: Variable to store result.
200 * @ptr: Source address, in user space.
201 *
202 * Context: User context only. This function may sleep.
203 *
204 * This macro copies a single simple variable from user space to kernel
205 * space. It supports simple types like char and int, but not larger
206 * data types like structures or arrays.
207 *
208 * @ptr must have pointer-to-simple-variable type, and the result of
209 * dereferencing @ptr must be assignable to @x without a cast.
210 *
211 * Caller must check the pointer with access_ok() before calling this
212 * function.
213 *
214 * Returns zero on success, or -EFAULT on error.
215 * On error, the variable @x is set to zero.
216 */
217#define __get_user(x,ptr) \
218 __get_user_nocheck((x), (ptr), sizeof(*(ptr)))
219
220struct __large_struct { unsigned long buf[100]; };
221#define __m(x) (*(struct __large_struct __user *)(x))
222
223/*
224 * Yuck. We need two variants, one for 64bit operation and one
225 * for 32 bit mode and old iron.
226 */
227#ifndef CONFIG_EVA
228#define __get_kernel_common(val, size, ptr) __get_user_common(val, size, ptr)
229#else
230/*
231 * Kernel specific functions for EVA. We need to use normal load instructions
232 * to read data from kernel when operating in EVA mode. We use these macros to
233 * avoid redefining __get_user_asm for EVA.
234 */
235#undef _loadd
236#undef _loadw
237#undef _loadh
238#undef _loadb
239#ifdef CONFIG_32BIT
240#define _loadd _loadw
241#else
242#define _loadd(reg, addr) "ld " reg ", " addr
243#endif
244#define _loadw(reg, addr) "lw " reg ", " addr
245#define _loadh(reg, addr) "lh " reg ", " addr
246#define _loadb(reg, addr) "lb " reg ", " addr
247
248#define __get_kernel_common(val, size, ptr) \
249do { \
250 switch (size) { \
251 case 1: __get_data_asm(val, _loadb, ptr); break; \
252 case 2: __get_data_asm(val, _loadh, ptr); break; \
253 case 4: __get_data_asm(val, _loadw, ptr); break; \
254 case 8: __GET_DW(val, _loadd, ptr); break; \
255 default: __get_user_unknown(); break; \
256 } \
257} while (0)
258#endif
259
260#ifdef CONFIG_32BIT
261#define __GET_DW(val, insn, ptr) __get_data_asm_ll32(val, insn, ptr)
262#endif
263#ifdef CONFIG_64BIT
264#define __GET_DW(val, insn, ptr) __get_data_asm(val, insn, ptr)
265#endif
266
267extern void __get_user_unknown(void);
268
269#define __get_user_common(val, size, ptr) \
270do { \
271 switch (size) { \
272 case 1: __get_data_asm(val, user_lb, ptr); break; \
273 case 2: __get_data_asm(val, user_lh, ptr); break; \
274 case 4: __get_data_asm(val, user_lw, ptr); break; \
275 case 8: __GET_DW(val, user_ld, ptr); break; \
276 default: __get_user_unknown(); break; \
277 } \
278} while (0)
279
280#define __get_user_nocheck(x, ptr, size) \
281({ \
282 int __gu_err; \
283 \
284 if (segment_eq(get_fs(), get_ds())) { \
285 __get_kernel_common((x), size, ptr); \
286 } else { \
287 __chk_user_ptr(ptr); \
288 __get_user_common((x), size, ptr); \
289 } \
290 __gu_err; \
291})
292
293#define __get_user_check(x, ptr, size) \
294({ \
295 int __gu_err = -EFAULT; \
296 const __typeof__(*(ptr)) __user * __gu_ptr = (ptr); \
297 \
298 might_fault(); \
299 if (likely(access_ok(VERIFY_READ, __gu_ptr, size))) { \
300 if (segment_eq(get_fs(), get_ds())) \
301 __get_kernel_common((x), size, __gu_ptr); \
302 else \
303 __get_user_common((x), size, __gu_ptr); \
304 } \
305 \
306 __gu_err; \
307})
308
309#define __get_data_asm(val, insn, addr) \
310{ \
311 long __gu_tmp; \
312 \
313 __asm__ __volatile__( \
314 "1: "insn("%1", "%3")" \n" \
315 "2: \n" \
316 " .insn \n" \
317 " .section .fixup,\"ax\" \n" \
318 "3: li %0, %4 \n" \
319 " j 2b \n" \
320 " .previous \n" \
321 " .section __ex_table,\"a\" \n" \
322 " "__UA_ADDR "\t1b, 3b \n" \
323 " .previous \n" \
324 : "=r" (__gu_err), "=r" (__gu_tmp) \
325 : "0" (0), "o" (__m(addr)), "i" (-EFAULT)); \
326 \
327 (val) = (__typeof__(*(addr))) __gu_tmp; \
328}
329
330/*
331 * Get a long long 64 using 32 bit registers.
332 */
333#define __get_data_asm_ll32(val, insn, addr) \
334{ \
335 union { \
336 unsigned long long l; \
337 __typeof__(*(addr)) t; \
338 } __gu_tmp; \
339 \
340 __asm__ __volatile__( \
341 "1: " insn("%1", "(%3)")" \n" \
342 "2: " insn("%D1", "4(%3)")" \n" \
343 "3: \n" \
344 " .insn \n" \
345 " .section .fixup,\"ax\" \n" \
346 "4: li %0, %4 \n" \
347 " move %1, $0 \n" \
348 " move %D1, $0 \n" \
349 " j 3b \n" \
350 " .previous \n" \
351 " .section __ex_table,\"a\" \n" \
352 " " __UA_ADDR " 1b, 4b \n" \
353 " " __UA_ADDR " 2b, 4b \n" \
354 " .previous \n" \
355 : "=r" (__gu_err), "=&r" (__gu_tmp.l) \
356 : "0" (0), "r" (addr), "i" (-EFAULT)); \
357 \
358 (val) = __gu_tmp.t; \
359}
360
361#ifndef CONFIG_EVA
362#define __put_kernel_common(ptr, size) __put_user_common(ptr, size)
363#else
364/*
365 * Kernel specific functions for EVA. We need to use normal load instructions
366 * to read data from kernel when operating in EVA mode. We use these macros to
367 * avoid redefining __get_data_asm for EVA.
368 */
369#undef _stored
370#undef _storew
371#undef _storeh
372#undef _storeb
373#ifdef CONFIG_32BIT
374#define _stored _storew
375#else
376#define _stored(reg, addr) "ld " reg ", " addr
377#endif
378
379#define _storew(reg, addr) "sw " reg ", " addr
380#define _storeh(reg, addr) "sh " reg ", " addr
381#define _storeb(reg, addr) "sb " reg ", " addr
382
383#define __put_kernel_common(ptr, size) \
384do { \
385 switch (size) { \
386 case 1: __put_data_asm(_storeb, ptr); break; \
387 case 2: __put_data_asm(_storeh, ptr); break; \
388 case 4: __put_data_asm(_storew, ptr); break; \
389 case 8: __PUT_DW(_stored, ptr); break; \
390 default: __put_user_unknown(); break; \
391 } \
392} while(0)
393#endif
394
395/*
396 * Yuck. We need two variants, one for 64bit operation and one
397 * for 32 bit mode and old iron.
398 */
399#ifdef CONFIG_32BIT
400#define __PUT_DW(insn, ptr) __put_data_asm_ll32(insn, ptr)
401#endif
402#ifdef CONFIG_64BIT
403#define __PUT_DW(insn, ptr) __put_data_asm(insn, ptr)
404#endif
405
406#define __put_user_common(ptr, size) \
407do { \
408 switch (size) { \
409 case 1: __put_data_asm(user_sb, ptr); break; \
410 case 2: __put_data_asm(user_sh, ptr); break; \
411 case 4: __put_data_asm(user_sw, ptr); break; \
412 case 8: __PUT_DW(user_sd, ptr); break; \
413 default: __put_user_unknown(); break; \
414 } \
415} while (0)
416
417#define __put_user_nocheck(x, ptr, size) \
418({ \
419 __typeof__(*(ptr)) __pu_val; \
420 int __pu_err = 0; \
421 \
422 __pu_val = (x); \
423 if (segment_eq(get_fs(), get_ds())) { \
424 __put_kernel_common(ptr, size); \
425 } else { \
426 __chk_user_ptr(ptr); \
427 __put_user_common(ptr, size); \
428 } \
429 __pu_err; \
430})
431
432#define __put_user_check(x, ptr, size) \
433({ \
434 __typeof__(*(ptr)) __user *__pu_addr = (ptr); \
435 __typeof__(*(ptr)) __pu_val = (x); \
436 int __pu_err = -EFAULT; \
437 \
438 might_fault(); \
439 if (likely(access_ok(VERIFY_WRITE, __pu_addr, size))) { \
440 if (segment_eq(get_fs(), get_ds())) \
441 __put_kernel_common(__pu_addr, size); \
442 else \
443 __put_user_common(__pu_addr, size); \
444 } \
445 \
446 __pu_err; \
447})
448
449#define __put_data_asm(insn, ptr) \
450{ \
451 __asm__ __volatile__( \
452 "1: "insn("%z2", "%3")" # __put_data_asm \n" \
453 "2: \n" \
454 " .insn \n" \
455 " .section .fixup,\"ax\" \n" \
456 "3: li %0, %4 \n" \
457 " j 2b \n" \
458 " .previous \n" \
459 " .section __ex_table,\"a\" \n" \
460 " " __UA_ADDR " 1b, 3b \n" \
461 " .previous \n" \
462 : "=r" (__pu_err) \
463 : "0" (0), "Jr" (__pu_val), "o" (__m(ptr)), \
464 "i" (-EFAULT)); \
465}
466
467#define __put_data_asm_ll32(insn, ptr) \
468{ \
469 __asm__ __volatile__( \
470 "1: "insn("%2", "(%3)")" # __put_data_asm_ll32 \n" \
471 "2: "insn("%D2", "4(%3)")" \n" \
472 "3: \n" \
473 " .insn \n" \
474 " .section .fixup,\"ax\" \n" \
475 "4: li %0, %4 \n" \
476 " j 3b \n" \
477 " .previous \n" \
478 " .section __ex_table,\"a\" \n" \
479 " " __UA_ADDR " 1b, 4b \n" \
480 " " __UA_ADDR " 2b, 4b \n" \
481 " .previous" \
482 : "=r" (__pu_err) \
483 : "0" (0), "r" (__pu_val), "r" (ptr), \
484 "i" (-EFAULT)); \
485}
486
487extern void __put_user_unknown(void);
488
489/*
490 * ul{b,h,w} are macros and there are no equivalent macros for EVA.
491 * EVA unaligned access is handled in the ADE exception handler.
492 */
493#ifndef CONFIG_EVA
494/*
495 * put_user_unaligned: - Write a simple value into user space.
496 * @x: Value to copy to user space.
497 * @ptr: Destination address, in user space.
498 *
499 * Context: User context only. This function may sleep.
500 *
501 * This macro copies a single simple value from kernel space to user
502 * space. It supports simple types like char and int, but not larger
503 * data types like structures or arrays.
504 *
505 * @ptr must have pointer-to-simple-variable type, and @x must be assignable
506 * to the result of dereferencing @ptr.
507 *
508 * Returns zero on success, or -EFAULT on error.
509 */
510#define put_user_unaligned(x,ptr) \
511 __put_user_unaligned_check((x),(ptr),sizeof(*(ptr)))
512
513/*
514 * get_user_unaligned: - Get a simple variable from user space.
515 * @x: Variable to store result.
516 * @ptr: Source address, in user space.
517 *
518 * Context: User context only. This function may sleep.
519 *
520 * This macro copies a single simple variable from user space to kernel
521 * space. It supports simple types like char and int, but not larger
522 * data types like structures or arrays.
523 *
524 * @ptr must have pointer-to-simple-variable type, and the result of
525 * dereferencing @ptr must be assignable to @x without a cast.
526 *
527 * Returns zero on success, or -EFAULT on error.
528 * On error, the variable @x is set to zero.
529 */
530#define get_user_unaligned(x,ptr) \
531 __get_user_unaligned_check((x),(ptr),sizeof(*(ptr)))
532
533/*
534 * __put_user_unaligned: - Write a simple value into user space, with less checking.
535 * @x: Value to copy to user space.
536 * @ptr: Destination address, in user space.
537 *
538 * Context: User context only. This function may sleep.
539 *
540 * This macro copies a single simple value from kernel space to user
541 * space. It supports simple types like char and int, but not larger
542 * data types like structures or arrays.
543 *
544 * @ptr must have pointer-to-simple-variable type, and @x must be assignable
545 * to the result of dereferencing @ptr.
546 *
547 * Caller must check the pointer with access_ok() before calling this
548 * function.
549 *
550 * Returns zero on success, or -EFAULT on error.
551 */
552#define __put_user_unaligned(x,ptr) \
553 __put_user_unaligned_nocheck((x),(ptr),sizeof(*(ptr)))
554
555/*
556 * __get_user_unaligned: - Get a simple variable from user space, with less checking.
557 * @x: Variable to store result.
558 * @ptr: Source address, in user space.
559 *
560 * Context: User context only. This function may sleep.
561 *
562 * This macro copies a single simple variable from user space to kernel
563 * space. It supports simple types like char and int, but not larger
564 * data types like structures or arrays.
565 *
566 * @ptr must have pointer-to-simple-variable type, and the result of
567 * dereferencing @ptr must be assignable to @x without a cast.
568 *
569 * Caller must check the pointer with access_ok() before calling this
570 * function.
571 *
572 * Returns zero on success, or -EFAULT on error.
573 * On error, the variable @x is set to zero.
574 */
575#define __get_user_unaligned(x,ptr) \
576 __get_user__unalignednocheck((x),(ptr),sizeof(*(ptr)))
577
578/*
579 * Yuck. We need two variants, one for 64bit operation and one
580 * for 32 bit mode and old iron.
581 */
582#ifdef CONFIG_32BIT
583#define __GET_USER_UNALIGNED_DW(val, ptr) \
584 __get_user_unaligned_asm_ll32(val, ptr)
585#endif
586#ifdef CONFIG_64BIT
587#define __GET_USER_UNALIGNED_DW(val, ptr) \
588 __get_user_unaligned_asm(val, "uld", ptr)
589#endif
590
591extern void __get_user_unaligned_unknown(void);
592
593#define __get_user_unaligned_common(val, size, ptr) \
594do { \
595 switch (size) { \
596 case 1: __get_data_asm(val, "lb", ptr); break; \
597 case 2: __get_user_unaligned_asm(val, "ulh", ptr); break; \
598 case 4: __get_user_unaligned_asm(val, "ulw", ptr); break; \
599 case 8: __GET_USER_UNALIGNED_DW(val, ptr); break; \
600 default: __get_user_unaligned_unknown(); break; \
601 } \
602} while (0)
603
604#define __get_user_unaligned_nocheck(x,ptr,size) \
605({ \
606 int __gu_err; \
607 \
608 __get_user_unaligned_common((x), size, ptr); \
609 __gu_err; \
610})
611
612#define __get_user_unaligned_check(x,ptr,size) \
613({ \
614 int __gu_err = -EFAULT; \
615 const __typeof__(*(ptr)) __user * __gu_ptr = (ptr); \
616 \
617 if (likely(access_ok(VERIFY_READ, __gu_ptr, size))) \
618 __get_user_unaligned_common((x), size, __gu_ptr); \
619 \
620 __gu_err; \
621})
622
623#define __get_data_unaligned_asm(val, insn, addr) \
624{ \
625 long __gu_tmp; \
626 \
627 __asm__ __volatile__( \
628 "1: " insn " %1, %3 \n" \
629 "2: \n" \
630 " .insn \n" \
631 " .section .fixup,\"ax\" \n" \
632 "3: li %0, %4 \n" \
633 " j 2b \n" \
634 " .previous \n" \
635 " .section __ex_table,\"a\" \n" \
636 " "__UA_ADDR "\t1b, 3b \n" \
637 " "__UA_ADDR "\t1b + 4, 3b \n" \
638 " .previous \n" \
639 : "=r" (__gu_err), "=r" (__gu_tmp) \
640 : "0" (0), "o" (__m(addr)), "i" (-EFAULT)); \
641 \
642 (val) = (__typeof__(*(addr))) __gu_tmp; \
643}
644
645/*
646 * Get a long long 64 using 32 bit registers.
647 */
648#define __get_user_unaligned_asm_ll32(val, addr) \
649{ \
650 unsigned long long __gu_tmp; \
651 \
652 __asm__ __volatile__( \
653 "1: ulw %1, (%3) \n" \
654 "2: ulw %D1, 4(%3) \n" \
655 " move %0, $0 \n" \
656 "3: \n" \
657 " .insn \n" \
658 " .section .fixup,\"ax\" \n" \
659 "4: li %0, %4 \n" \
660 " move %1, $0 \n" \
661 " move %D1, $0 \n" \
662 " j 3b \n" \
663 " .previous \n" \
664 " .section __ex_table,\"a\" \n" \
665 " " __UA_ADDR " 1b, 4b \n" \
666 " " __UA_ADDR " 1b + 4, 4b \n" \
667 " " __UA_ADDR " 2b, 4b \n" \
668 " " __UA_ADDR " 2b + 4, 4b \n" \
669 " .previous \n" \
670 : "=r" (__gu_err), "=&r" (__gu_tmp) \
671 : "0" (0), "r" (addr), "i" (-EFAULT)); \
672 (val) = (__typeof__(*(addr))) __gu_tmp; \
673}
674
675/*
676 * Yuck. We need two variants, one for 64bit operation and one
677 * for 32 bit mode and old iron.
678 */
679#ifdef CONFIG_32BIT
680#define __PUT_USER_UNALIGNED_DW(ptr) __put_user_unaligned_asm_ll32(ptr)
681#endif
682#ifdef CONFIG_64BIT
683#define __PUT_USER_UNALIGNED_DW(ptr) __put_user_unaligned_asm("usd", ptr)
684#endif
685
686#define __put_user_unaligned_common(ptr, size) \
687do { \
688 switch (size) { \
689 case 1: __put_data_asm("sb", ptr); break; \
690 case 2: __put_user_unaligned_asm("ush", ptr); break; \
691 case 4: __put_user_unaligned_asm("usw", ptr); break; \
692 case 8: __PUT_USER_UNALIGNED_DW(ptr); break; \
693 default: __put_user_unaligned_unknown(); break; \
694} while (0)
695
696#define __put_user_unaligned_nocheck(x,ptr,size) \
697({ \
698 __typeof__(*(ptr)) __pu_val; \
699 int __pu_err = 0; \
700 \
701 __pu_val = (x); \
702 __put_user_unaligned_common(ptr, size); \
703 __pu_err; \
704})
705
706#define __put_user_unaligned_check(x,ptr,size) \
707({ \
708 __typeof__(*(ptr)) __user *__pu_addr = (ptr); \
709 __typeof__(*(ptr)) __pu_val = (x); \
710 int __pu_err = -EFAULT; \
711 \
712 if (likely(access_ok(VERIFY_WRITE, __pu_addr, size))) \
713 __put_user_unaligned_common(__pu_addr, size); \
714 \
715 __pu_err; \
716})
717
718#define __put_user_unaligned_asm(insn, ptr) \
719{ \
720 __asm__ __volatile__( \
721 "1: " insn " %z2, %3 # __put_user_unaligned_asm\n" \
722 "2: \n" \
723 " .insn \n" \
724 " .section .fixup,\"ax\" \n" \
725 "3: li %0, %4 \n" \
726 " j 2b \n" \
727 " .previous \n" \
728 " .section __ex_table,\"a\" \n" \
729 " " __UA_ADDR " 1b, 3b \n" \
730 " .previous \n" \
731 : "=r" (__pu_err) \
732 : "0" (0), "Jr" (__pu_val), "o" (__m(ptr)), \
733 "i" (-EFAULT)); \
734}
735
736#define __put_user_unaligned_asm_ll32(ptr) \
737{ \
738 __asm__ __volatile__( \
739 "1: sw %2, (%3) # __put_user_unaligned_asm_ll32 \n" \
740 "2: sw %D2, 4(%3) \n" \
741 "3: \n" \
742 " .insn \n" \
743 " .section .fixup,\"ax\" \n" \
744 "4: li %0, %4 \n" \
745 " j 3b \n" \
746 " .previous \n" \
747 " .section __ex_table,\"a\" \n" \
748 " " __UA_ADDR " 1b, 4b \n" \
749 " " __UA_ADDR " 1b + 4, 4b \n" \
750 " " __UA_ADDR " 2b, 4b \n" \
751 " " __UA_ADDR " 2b + 4, 4b \n" \
752 " .previous" \
753 : "=r" (__pu_err) \
754 : "0" (0), "r" (__pu_val), "r" (ptr), \
755 "i" (-EFAULT)); \
756}
757
758extern void __put_user_unaligned_unknown(void);
759#endif
760
761/*
762 * We're generating jump to subroutines which will be outside the range of
763 * jump instructions
764 */
765#ifdef MODULE
766#define __MODULE_JAL(destination) \
767 ".set\tnoat\n\t" \
768 __UA_LA "\t$1, " #destination "\n\t" \
769 "jalr\t$1\n\t" \
770 ".set\tat\n\t"
771#else
772#define __MODULE_JAL(destination) \
773 "jal\t" #destination "\n\t"
774#endif
775
776#ifndef CONFIG_CPU_DADDI_WORKAROUNDS
777#define DADDI_SCRATCH "$0"
778#else
779#define DADDI_SCRATCH "$3"
780#endif
781
782extern size_t __copy_user(void *__to, const void *__from, size_t __n);
783
784#ifndef CONFIG_EVA
785#define __invoke_copy_to_user(to, from, n) \
786({ \
787 register void __user *__cu_to_r __asm__("$4"); \
788 register const void *__cu_from_r __asm__("$5"); \
789 register long __cu_len_r __asm__("$6"); \
790 \
791 __cu_to_r = (to); \
792 __cu_from_r = (from); \
793 __cu_len_r = (n); \
794 __asm__ __volatile__( \
795 __MODULE_JAL(__copy_user) \
796 : "+r" (__cu_to_r), "+r" (__cu_from_r), "+r" (__cu_len_r) \
797 : \
798 : "$8", "$9", "$10", "$11", "$12", "$14", "$15", "$24", "$31", \
799 DADDI_SCRATCH, "memory"); \
800 __cu_len_r; \
801})
802
803#define __invoke_copy_to_kernel(to, from, n) \
804 __invoke_copy_to_user(to, from, n)
805
806#endif
807
808/*
809 * __copy_to_user: - Copy a block of data into user space, with less checking.
810 * @to: Destination address, in user space.
811 * @from: Source address, in kernel space.
812 * @n: Number of bytes to copy.
813 *
814 * Context: User context only. This function may sleep.
815 *
816 * Copy data from kernel space to user space. Caller must check
817 * the specified block with access_ok() before calling this function.
818 *
819 * Returns number of bytes that could not be copied.
820 * On success, this will be zero.
821 */
822#define __copy_to_user(to, from, n) \
823({ \
824 void __user *__cu_to; \
825 const void *__cu_from; \
826 long __cu_len; \
827 \
828 __cu_to = (to); \
829 __cu_from = (from); \
830 __cu_len = (n); \
831 might_fault(); \
832 if (segment_eq(get_fs(), get_ds())) \
833 __cu_len = __invoke_copy_to_kernel(__cu_to, __cu_from, \
834 __cu_len); \
835 else \
836 __cu_len = __invoke_copy_to_user(__cu_to, __cu_from, \
837 __cu_len); \
838 __cu_len; \
839})
840
841extern size_t __copy_user_inatomic(void *__to, const void *__from, size_t __n);
842
843#define __copy_to_user_inatomic(to, from, n) \
844({ \
845 void __user *__cu_to; \
846 const void *__cu_from; \
847 long __cu_len; \
848 \
849 __cu_to = (to); \
850 __cu_from = (from); \
851 __cu_len = (n); \
852 if (segment_eq(get_fs(), get_ds())) \
853 __cu_len = __invoke_copy_to_kernel(__cu_to, __cu_from, \
854 __cu_len); \
855 else \
856 __cu_len = __invoke_copy_to_user(__cu_to, __cu_from, \
857 __cu_len); \
858 __cu_len; \
859})
860
861#define __copy_from_user_inatomic(to, from, n) \
862({ \
863 void *__cu_to; \
864 const void __user *__cu_from; \
865 long __cu_len; \
866 \
867 __cu_to = (to); \
868 __cu_from = (from); \
869 __cu_len = (n); \
870 if (segment_eq(get_fs(), get_ds())) \
871 __cu_len = __invoke_copy_from_kernel_inatomic(__cu_to, \
872 __cu_from,\
873 __cu_len);\
874 else \
875 __cu_len = __invoke_copy_from_user_inatomic(__cu_to, \
876 __cu_from, \
877 __cu_len); \
878 __cu_len; \
879})
880
881/*
882 * copy_to_user: - Copy a block of data into user space.
883 * @to: Destination address, in user space.
884 * @from: Source address, in kernel space.
885 * @n: Number of bytes to copy.
886 *
887 * Context: User context only. This function may sleep.
888 *
889 * Copy data from kernel space to user space.
890 *
891 * Returns number of bytes that could not be copied.
892 * On success, this will be zero.
893 */
894#define copy_to_user(to, from, n) \
895({ \
896 void __user *__cu_to; \
897 const void *__cu_from; \
898 long __cu_len; \
899 \
900 __cu_to = (to); \
901 __cu_from = (from); \
902 __cu_len = (n); \
903 if (segment_eq(get_fs(), get_ds())) { \
904 __cu_len = __invoke_copy_to_kernel(__cu_to, \
905 __cu_from, \
906 __cu_len); \
907 } else { \
908 if (access_ok(VERIFY_WRITE, __cu_to, __cu_len)) { \
909 might_fault(); \
910 __cu_len = __invoke_copy_to_user(__cu_to, \
911 __cu_from, \
912 __cu_len); \
913 } \
914 } \
915 __cu_len; \
916})
917
918#ifndef CONFIG_EVA
919
920#define __invoke_copy_from_user(to, from, n) \
921({ \
922 register void *__cu_to_r __asm__("$4"); \
923 register const void __user *__cu_from_r __asm__("$5"); \
924 register long __cu_len_r __asm__("$6"); \
925 \
926 __cu_to_r = (to); \
927 __cu_from_r = (from); \
928 __cu_len_r = (n); \
929 __asm__ __volatile__( \
930 ".set\tnoreorder\n\t" \
931 __MODULE_JAL(__copy_user) \
932 ".set\tnoat\n\t" \
933 __UA_ADDU "\t$1, %1, %2\n\t" \
934 ".set\tat\n\t" \
935 ".set\treorder" \
936 : "+r" (__cu_to_r), "+r" (__cu_from_r), "+r" (__cu_len_r) \
937 : \
938 : "$8", "$9", "$10", "$11", "$12", "$14", "$15", "$24", "$31", \
939 DADDI_SCRATCH, "memory"); \
940 __cu_len_r; \
941})
942
943#define __invoke_copy_from_kernel(to, from, n) \
944 __invoke_copy_from_user(to, from, n)
945
946/* For userland <-> userland operations */
947#define ___invoke_copy_in_user(to, from, n) \
948 __invoke_copy_from_user(to, from, n)
949
950/* For kernel <-> kernel operations */
951#define ___invoke_copy_in_kernel(to, from, n) \
952 __invoke_copy_from_user(to, from, n)
953
954#define __invoke_copy_from_user_inatomic(to, from, n) \
955({ \
956 register void *__cu_to_r __asm__("$4"); \
957 register const void __user *__cu_from_r __asm__("$5"); \
958 register long __cu_len_r __asm__("$6"); \
959 \
960 __cu_to_r = (to); \
961 __cu_from_r = (from); \
962 __cu_len_r = (n); \
963 __asm__ __volatile__( \
964 ".set\tnoreorder\n\t" \
965 __MODULE_JAL(__copy_user_inatomic) \
966 ".set\tnoat\n\t" \
967 __UA_ADDU "\t$1, %1, %2\n\t" \
968 ".set\tat\n\t" \
969 ".set\treorder" \
970 : "+r" (__cu_to_r), "+r" (__cu_from_r), "+r" (__cu_len_r) \
971 : \
972 : "$8", "$9", "$10", "$11", "$12", "$14", "$15", "$24", "$31", \
973 DADDI_SCRATCH, "memory"); \
974 __cu_len_r; \
975})
976
977#define __invoke_copy_from_kernel_inatomic(to, from, n) \
978 __invoke_copy_from_user_inatomic(to, from, n) \
979
980#else
981
982/* EVA specific functions */
983
984extern size_t __copy_user_inatomic_eva(void *__to, const void *__from,
985 size_t __n);
986extern size_t __copy_from_user_eva(void *__to, const void *__from,
987 size_t __n);
988extern size_t __copy_to_user_eva(void *__to, const void *__from,
989 size_t __n);
990extern size_t __copy_in_user_eva(void *__to, const void *__from, size_t __n);
991
992#define __invoke_copy_from_user_eva_generic(to, from, n, func_ptr) \
993({ \
994 register void *__cu_to_r __asm__("$4"); \
995 register const void __user *__cu_from_r __asm__("$5"); \
996 register long __cu_len_r __asm__("$6"); \
997 \
998 __cu_to_r = (to); \
999 __cu_from_r = (from); \
1000 __cu_len_r = (n); \
1001 __asm__ __volatile__( \
1002 ".set\tnoreorder\n\t" \
1003 __MODULE_JAL(func_ptr) \
1004 ".set\tnoat\n\t" \
1005 __UA_ADDU "\t$1, %1, %2\n\t" \
1006 ".set\tat\n\t" \
1007 ".set\treorder" \
1008 : "+r" (__cu_to_r), "+r" (__cu_from_r), "+r" (__cu_len_r) \
1009 : \
1010 : "$8", "$9", "$10", "$11", "$12", "$14", "$15", "$24", "$31", \
1011 DADDI_SCRATCH, "memory"); \
1012 __cu_len_r; \
1013})
1014
1015#define __invoke_copy_to_user_eva_generic(to, from, n, func_ptr) \
1016({ \
1017 register void *__cu_to_r __asm__("$4"); \
1018 register const void __user *__cu_from_r __asm__("$5"); \
1019 register long __cu_len_r __asm__("$6"); \
1020 \
1021 __cu_to_r = (to); \
1022 __cu_from_r = (from); \
1023 __cu_len_r = (n); \
1024 __asm__ __volatile__( \
1025 __MODULE_JAL(func_ptr) \
1026 : "+r" (__cu_to_r), "+r" (__cu_from_r), "+r" (__cu_len_r) \
1027 : \
1028 : "$8", "$9", "$10", "$11", "$12", "$14", "$15", "$24", "$31", \
1029 DADDI_SCRATCH, "memory"); \
1030 __cu_len_r; \
1031})
1032
1033/*
1034 * Source or destination address is in userland. We need to go through
1035 * the TLB
1036 */
1037#define __invoke_copy_from_user(to, from, n) \
1038 __invoke_copy_from_user_eva_generic(to, from, n, __copy_from_user_eva)
1039
1040#define __invoke_copy_from_user_inatomic(to, from, n) \
1041 __invoke_copy_from_user_eva_generic(to, from, n, \
1042 __copy_user_inatomic_eva)
1043
1044#define __invoke_copy_to_user(to, from, n) \
1045 __invoke_copy_to_user_eva_generic(to, from, n, __copy_to_user_eva)
1046
1047#define ___invoke_copy_in_user(to, from, n) \
1048 __invoke_copy_from_user_eva_generic(to, from, n, __copy_in_user_eva)
1049
1050/*
1051 * Source or destination address in the kernel. We are not going through
1052 * the TLB
1053 */
1054#define __invoke_copy_from_kernel(to, from, n) \
1055 __invoke_copy_from_user_eva_generic(to, from, n, __copy_user)
1056
1057#define __invoke_copy_from_kernel_inatomic(to, from, n) \
1058 __invoke_copy_from_user_eva_generic(to, from, n, __copy_user_inatomic)
1059
1060#define __invoke_copy_to_kernel(to, from, n) \
1061 __invoke_copy_to_user_eva_generic(to, from, n, __copy_user)
1062
1063#define ___invoke_copy_in_kernel(to, from, n) \
1064 __invoke_copy_from_user_eva_generic(to, from, n, __copy_user)
1065
1066#endif /* CONFIG_EVA */
1067
1068/*
1069 * __copy_from_user: - Copy a block of data from user space, with less checking.
1070 * @to: Destination address, in kernel space.
1071 * @from: Source address, in user space.
1072 * @n: Number of bytes to copy.
1073 *
1074 * Context: User context only. This function may sleep.
1075 *
1076 * Copy data from user space to kernel space. Caller must check
1077 * the specified block with access_ok() before calling this function.
1078 *
1079 * Returns number of bytes that could not be copied.
1080 * On success, this will be zero.
1081 *
1082 * If some data could not be copied, this function will pad the copied
1083 * data to the requested size using zero bytes.
1084 */
1085#define __copy_from_user(to, from, n) \
1086({ \
1087 void *__cu_to; \
1088 const void __user *__cu_from; \
1089 long __cu_len; \
1090 \
1091 __cu_to = (to); \
1092 __cu_from = (from); \
1093 __cu_len = (n); \
1094 might_fault(); \
1095 __cu_len = __invoke_copy_from_user(__cu_to, __cu_from, \
1096 __cu_len); \
1097 __cu_len; \
1098})
1099
1100/*
1101 * copy_from_user: - Copy a block of data from user space.
1102 * @to: Destination address, in kernel space.
1103 * @from: Source address, in user space.
1104 * @n: Number of bytes to copy.
1105 *
1106 * Context: User context only. This function may sleep.
1107 *
1108 * Copy data from user space to kernel space.
1109 *
1110 * Returns number of bytes that could not be copied.
1111 * On success, this will be zero.
1112 *
1113 * If some data could not be copied, this function will pad the copied
1114 * data to the requested size using zero bytes.
1115 */
1116#define copy_from_user(to, from, n) \
1117({ \
1118 void *__cu_to; \
1119 const void __user *__cu_from; \
1120 long __cu_len; \
1121 \
1122 __cu_to = (to); \
1123 __cu_from = (from); \
1124 __cu_len = (n); \
1125 if (segment_eq(get_fs(), get_ds())) { \
1126 __cu_len = __invoke_copy_from_kernel(__cu_to, \
1127 __cu_from, \
1128 __cu_len); \
1129 } else { \
1130 if (access_ok(VERIFY_READ, __cu_from, __cu_len)) { \
1131 might_fault(); \
1132 __cu_len = __invoke_copy_from_user(__cu_to, \
1133 __cu_from, \
1134 __cu_len); \
1135 } \
1136 } \
1137 __cu_len; \
1138})
1139
1140#define __copy_in_user(to, from, n) \
1141({ \
1142 void __user *__cu_to; \
1143 const void __user *__cu_from; \
1144 long __cu_len; \
1145 \
1146 __cu_to = (to); \
1147 __cu_from = (from); \
1148 __cu_len = (n); \
1149 if (segment_eq(get_fs(), get_ds())) { \
1150 __cu_len = ___invoke_copy_in_kernel(__cu_to, __cu_from, \
1151 __cu_len); \
1152 } else { \
1153 might_fault(); \
1154 __cu_len = ___invoke_copy_in_user(__cu_to, __cu_from, \
1155 __cu_len); \
1156 } \
1157 __cu_len; \
1158})
1159
1160#define copy_in_user(to, from, n) \
1161({ \
1162 void __user *__cu_to; \
1163 const void __user *__cu_from; \
1164 long __cu_len; \
1165 \
1166 __cu_to = (to); \
1167 __cu_from = (from); \
1168 __cu_len = (n); \
1169 if (segment_eq(get_fs(), get_ds())) { \
1170 __cu_len = ___invoke_copy_in_kernel(__cu_to,__cu_from, \
1171 __cu_len); \
1172 } else { \
1173 if (likely(access_ok(VERIFY_READ, __cu_from, __cu_len) &&\
1174 access_ok(VERIFY_WRITE, __cu_to, __cu_len))) {\
1175 might_fault(); \
1176 __cu_len = ___invoke_copy_in_user(__cu_to, \
1177 __cu_from, \
1178 __cu_len); \
1179 } \
1180 } \
1181 __cu_len; \
1182})
1183
1184/*
1185 * __clear_user: - Zero a block of memory in user space, with less checking.
1186 * @to: Destination address, in user space.
1187 * @n: Number of bytes to zero.
1188 *
1189 * Zero a block of memory in user space. Caller must check
1190 * the specified block with access_ok() before calling this function.
1191 *
1192 * Returns number of bytes that could not be cleared.
1193 * On success, this will be zero.
1194 */
1195static inline __kernel_size_t
1196__clear_user(void __user *addr, __kernel_size_t size)
1197{
1198 __kernel_size_t res;
1199
1200 might_fault();
1201 __asm__ __volatile__(
1202 "move\t$4, %1\n\t"
1203 "move\t$5, $0\n\t"
1204 "move\t$6, %2\n\t"
1205 __MODULE_JAL(__bzero)
1206 "move\t%0, $6"
1207 : "=r" (res)
1208 : "r" (addr), "r" (size)
1209 : "$4", "$5", "$6", __UA_t0, __UA_t1, "$31");
1210
1211 return res;
1212}
1213
1214#define clear_user(addr,n) \
1215({ \
1216 void __user * __cl_addr = (addr); \
1217 unsigned long __cl_size = (n); \
1218 if (__cl_size && access_ok(VERIFY_WRITE, \
1219 __cl_addr, __cl_size)) \
1220 __cl_size = __clear_user(__cl_addr, __cl_size); \
1221 __cl_size; \
1222})
1223
1224/*
1225 * __strncpy_from_user: - Copy a NUL terminated string from userspace, with less checking.
1226 * @dst: Destination address, in kernel space. This buffer must be at
1227 * least @count bytes long.
1228 * @src: Source address, in user space.
1229 * @count: Maximum number of bytes to copy, including the trailing NUL.
1230 *
1231 * Copies a NUL-terminated string from userspace to kernel space.
1232 * Caller must check the specified block with access_ok() before calling
1233 * this function.
1234 *
1235 * On success, returns the length of the string (not including the trailing
1236 * NUL).
1237 *
1238 * If access to userspace fails, returns -EFAULT (some data may have been
1239 * copied).
1240 *
1241 * If @count is smaller than the length of the string, copies @count bytes
1242 * and returns @count.
1243 */
1244static inline long
1245__strncpy_from_user(char *__to, const char __user *__from, long __len)
1246{
1247 long res;
1248
1249 if (segment_eq(get_fs(), get_ds())) {
1250 __asm__ __volatile__(
1251 "move\t$4, %1\n\t"
1252 "move\t$5, %2\n\t"
1253 "move\t$6, %3\n\t"
1254 __MODULE_JAL(__strncpy_from_kernel_nocheck_asm)
1255 "move\t%0, $2"
1256 : "=r" (res)
1257 : "r" (__to), "r" (__from), "r" (__len)
1258 : "$2", "$3", "$4", "$5", "$6", __UA_t0, "$31", "memory");
1259 } else {
1260 might_fault();
1261 __asm__ __volatile__(
1262 "move\t$4, %1\n\t"
1263 "move\t$5, %2\n\t"
1264 "move\t$6, %3\n\t"
1265 __MODULE_JAL(__strncpy_from_user_nocheck_asm)
1266 "move\t%0, $2"
1267 : "=r" (res)
1268 : "r" (__to), "r" (__from), "r" (__len)
1269 : "$2", "$3", "$4", "$5", "$6", __UA_t0, "$31", "memory");
1270 }
1271
1272 return res;
1273}
1274
1275/*
1276 * strncpy_from_user: - Copy a NUL terminated string from userspace.
1277 * @dst: Destination address, in kernel space. This buffer must be at
1278 * least @count bytes long.
1279 * @src: Source address, in user space.
1280 * @count: Maximum number of bytes to copy, including the trailing NUL.
1281 *
1282 * Copies a NUL-terminated string from userspace to kernel space.
1283 *
1284 * On success, returns the length of the string (not including the trailing
1285 * NUL).
1286 *
1287 * If access to userspace fails, returns -EFAULT (some data may have been
1288 * copied).
1289 *
1290 * If @count is smaller than the length of the string, copies @count bytes
1291 * and returns @count.
1292 */
1293static inline long
1294strncpy_from_user(char *__to, const char __user *__from, long __len)
1295{
1296 long res;
1297
1298 if (segment_eq(get_fs(), get_ds())) {
1299 __asm__ __volatile__(
1300 "move\t$4, %1\n\t"
1301 "move\t$5, %2\n\t"
1302 "move\t$6, %3\n\t"
1303 __MODULE_JAL(__strncpy_from_kernel_asm)
1304 "move\t%0, $2"
1305 : "=r" (res)
1306 : "r" (__to), "r" (__from), "r" (__len)
1307 : "$2", "$3", "$4", "$5", "$6", __UA_t0, "$31", "memory");
1308 } else {
1309 might_fault();
1310 __asm__ __volatile__(
1311 "move\t$4, %1\n\t"
1312 "move\t$5, %2\n\t"
1313 "move\t$6, %3\n\t"
1314 __MODULE_JAL(__strncpy_from_user_asm)
1315 "move\t%0, $2"
1316 : "=r" (res)
1317 : "r" (__to), "r" (__from), "r" (__len)
1318 : "$2", "$3", "$4", "$5", "$6", __UA_t0, "$31", "memory");
1319 }
1320
1321 return res;
1322}
1323
1324/* Returns: 0 if bad, string length+1 (memory size) of string if ok */
1325static inline long __strlen_user(const char __user *s)
1326{
1327 long res;
1328
1329 if (segment_eq(get_fs(), get_ds())) {
1330 __asm__ __volatile__(
1331 "move\t$4, %1\n\t"
1332 __MODULE_JAL(__strlen_kernel_nocheck_asm)
1333 "move\t%0, $2"
1334 : "=r" (res)
1335 : "r" (s)
1336 : "$2", "$4", __UA_t0, "$31");
1337 } else {
1338 might_fault();
1339 __asm__ __volatile__(
1340 "move\t$4, %1\n\t"
1341 __MODULE_JAL(__strlen_user_nocheck_asm)
1342 "move\t%0, $2"
1343 : "=r" (res)
1344 : "r" (s)
1345 : "$2", "$4", __UA_t0, "$31");
1346 }
1347
1348 return res;
1349}
1350
1351/*
1352 * strlen_user: - Get the size of a string in user space.
1353 * @str: The string to measure.
1354 *
1355 * Context: User context only. This function may sleep.
1356 *
1357 * Get the size of a NUL-terminated string in user space.
1358 *
1359 * Returns the size of the string INCLUDING the terminating NUL.
1360 * On exception, returns 0.
1361 *
1362 * If there is a limit on the length of a valid string, you may wish to
1363 * consider using strnlen_user() instead.
1364 */
1365static inline long strlen_user(const char __user *s)
1366{
1367 long res;
1368
1369 if (segment_eq(get_fs(), get_ds())) {
1370 __asm__ __volatile__(
1371 "move\t$4, %1\n\t"
1372 __MODULE_JAL(__strlen_kernel_asm)
1373 "move\t%0, $2"
1374 : "=r" (res)
1375 : "r" (s)
1376 : "$2", "$4", __UA_t0, "$31");
1377 } else {
1378 might_fault();
1379 __asm__ __volatile__(
1380 "move\t$4, %1\n\t"
1381 __MODULE_JAL(__strlen_kernel_asm)
1382 "move\t%0, $2"
1383 : "=r" (res)
1384 : "r" (s)
1385 : "$2", "$4", __UA_t0, "$31");
1386 }
1387
1388 return res;
1389}
1390
1391/* Returns: 0 if bad, string length+1 (memory size) of string if ok */
1392static inline long __strnlen_user(const char __user *s, long n)
1393{
1394 long res;
1395
1396 if (segment_eq(get_fs(), get_ds())) {
1397 __asm__ __volatile__(
1398 "move\t$4, %1\n\t"
1399 "move\t$5, %2\n\t"
1400 __MODULE_JAL(__strnlen_kernel_nocheck_asm)
1401 "move\t%0, $2"
1402 : "=r" (res)
1403 : "r" (s), "r" (n)
1404 : "$2", "$4", "$5", __UA_t0, "$31");
1405 } else {
1406 might_fault();
1407 __asm__ __volatile__(
1408 "move\t$4, %1\n\t"
1409 "move\t$5, %2\n\t"
1410 __MODULE_JAL(__strnlen_user_nocheck_asm)
1411 "move\t%0, $2"
1412 : "=r" (res)
1413 : "r" (s), "r" (n)
1414 : "$2", "$4", "$5", __UA_t0, "$31");
1415 }
1416
1417 return res;
1418}
1419
1420/*
1421 * strlen_user: - Get the size of a string in user space.
1422 * @str: The string to measure.
1423 *
1424 * Context: User context only. This function may sleep.
1425 *
1426 * Get the size of a NUL-terminated string in user space.
1427 *
1428 * Returns the size of the string INCLUDING the terminating NUL.
1429 * On exception, returns 0.
1430 *
1431 * If there is a limit on the length of a valid string, you may wish to
1432 * consider using strnlen_user() instead.
1433 */
1434static inline long strnlen_user(const char __user *s, long n)
1435{
1436 long res;
1437
1438 might_fault();
1439 if (segment_eq(get_fs(), get_ds())) {
1440 __asm__ __volatile__(
1441 "move\t$4, %1\n\t"
1442 "move\t$5, %2\n\t"
1443 __MODULE_JAL(__strnlen_kernel_asm)
1444 "move\t%0, $2"
1445 : "=r" (res)
1446 : "r" (s), "r" (n)
1447 : "$2", "$4", "$5", __UA_t0, "$31");
1448 } else {
1449 __asm__ __volatile__(
1450 "move\t$4, %1\n\t"
1451 "move\t$5, %2\n\t"
1452 __MODULE_JAL(__strnlen_user_asm)
1453 "move\t%0, $2"
1454 : "=r" (res)
1455 : "r" (s), "r" (n)
1456 : "$2", "$4", "$5", __UA_t0, "$31");
1457 }
1458
1459 return res;
1460}
1461
1462struct exception_table_entry
1463{
1464 unsigned long insn;
1465 unsigned long nextinsn;
1466};
1467
1468extern int fixup_exception(struct pt_regs *regs);
1469
1470#endif /* _ASM_UACCESS_H */