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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 <linux/string.h>
18#include <asm/asm-eva.h>
19#include <asm/extable.h>
20
21/*
22 * The fs value determines whether argument validity checking should be
23 * performed or not. If get_fs() == USER_DS, checking is performed, with
24 * get_fs() == KERNEL_DS, checking is bypassed.
25 *
26 * For historical reasons, these macros are grossly misnamed.
27 */
28#ifdef CONFIG_32BIT
29
30#ifdef CONFIG_KVM_GUEST
31#define __UA_LIMIT 0x40000000UL
32#else
33#define __UA_LIMIT 0x80000000UL
34#endif
35
36#define __UA_ADDR ".word"
37#define __UA_LA "la"
38#define __UA_ADDU "addu"
39#define __UA_t0 "$8"
40#define __UA_t1 "$9"
41
42#endif /* CONFIG_32BIT */
43
44#ifdef CONFIG_64BIT
45
46extern u64 __ua_limit;
47
48#define __UA_LIMIT __ua_limit
49
50#define __UA_ADDR ".dword"
51#define __UA_LA "dla"
52#define __UA_ADDU "daddu"
53#define __UA_t0 "$12"
54#define __UA_t1 "$13"
55
56#endif /* CONFIG_64BIT */
57
58/*
59 * USER_DS is a bitmask that has the bits set that may not be set in a valid
60 * userspace address. Note that we limit 32-bit userspace to 0x7fff8000 but
61 * the arithmetic we're doing only works if the limit is a power of two, so
62 * we use 0x80000000 here on 32-bit kernels. If a process passes an invalid
63 * address in this range it's the process's problem, not ours :-)
64 */
65
66#ifdef CONFIG_KVM_GUEST
67#define KERNEL_DS ((mm_segment_t) { 0x80000000UL })
68#define USER_DS ((mm_segment_t) { 0xC0000000UL })
69#else
70#define KERNEL_DS ((mm_segment_t) { 0UL })
71#define USER_DS ((mm_segment_t) { __UA_LIMIT })
72#endif
73
74#define VERIFY_READ 0
75#define VERIFY_WRITE 1
76
77#define get_ds() (KERNEL_DS)
78#define get_fs() (current_thread_info()->addr_limit)
79#define set_fs(x) (current_thread_info()->addr_limit = (x))
80
81#define segment_eq(a, b) ((a).seg == (b).seg)
82
83/*
84 * eva_kernel_access() - determine whether kernel memory access on an EVA system
85 *
86 * Determines whether memory accesses should be performed to kernel memory
87 * on a system using Extended Virtual Addressing (EVA).
88 *
89 * Return: true if a kernel memory access on an EVA system, else false.
90 */
91static inline bool eva_kernel_access(void)
92{
93 if (!IS_ENABLED(CONFIG_EVA))
94 return false;
95
96 return segment_eq(get_fs(), get_ds());
97}
98
99/*
100 * Is a address valid? This does a straightforward calculation rather
101 * than tests.
102 *
103 * Address valid if:
104 * - "addr" doesn't have any high-bits set
105 * - AND "size" doesn't have any high-bits set
106 * - AND "addr+size" doesn't have any high-bits set
107 * - OR we are in kernel mode.
108 *
109 * __ua_size() is a trick to avoid runtime checking of positive constant
110 * sizes; for those we already know at compile time that the size is ok.
111 */
112#define __ua_size(size) \
113 ((__builtin_constant_p(size) && (signed long) (size) > 0) ? 0 : (size))
114
115/*
116 * access_ok: - Checks if a user space pointer is valid
117 * @type: Type of access: %VERIFY_READ or %VERIFY_WRITE. Note that
118 * %VERIFY_WRITE is a superset of %VERIFY_READ - if it is safe
119 * to write to a block, it is always safe to read from it.
120 * @addr: User space pointer to start of block to check
121 * @size: Size of block to check
122 *
123 * Context: User context only. This function may sleep if pagefaults are
124 * enabled.
125 *
126 * Checks if a pointer to a block of memory in user space is valid.
127 *
128 * Returns true (nonzero) if the memory block may be valid, false (zero)
129 * if it is definitely invalid.
130 *
131 * Note that, depending on architecture, this function probably just
132 * checks that the pointer is in the user space range - after calling
133 * this function, memory access functions may still return -EFAULT.
134 */
135
136#define __access_mask get_fs().seg
137
138#define __access_ok(addr, size, mask) \
139({ \
140 unsigned long __addr = (unsigned long) (addr); \
141 unsigned long __size = size; \
142 unsigned long __mask = mask; \
143 unsigned long __ok; \
144 \
145 __chk_user_ptr(addr); \
146 __ok = (signed long)(__mask & (__addr | (__addr + __size) | \
147 __ua_size(__size))); \
148 __ok == 0; \
149})
150
151#define access_ok(type, addr, size) \
152 likely(__access_ok((addr), (size), __access_mask))
153
154/*
155 * put_user: - Write a simple value into user space.
156 * @x: Value to copy to user space.
157 * @ptr: Destination address, in user space.
158 *
159 * Context: User context only. This function may sleep if pagefaults are
160 * enabled.
161 *
162 * This macro copies a single simple value from kernel space to user
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 @x must be assignable
167 * to the result of dereferencing @ptr.
168 *
169 * Returns zero on success, or -EFAULT on error.
170 */
171#define put_user(x,ptr) \
172 __put_user_check((x), (ptr), sizeof(*(ptr)))
173
174/*
175 * get_user: - Get a simple variable from user space.
176 * @x: Variable to store result.
177 * @ptr: Source address, in user space.
178 *
179 * Context: User context only. This function may sleep if pagefaults are
180 * enabled.
181 *
182 * This macro copies a single simple variable from user space to kernel
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 the result of
187 * dereferencing @ptr must be assignable to @x without a cast.
188 *
189 * Returns zero on success, or -EFAULT on error.
190 * On error, the variable @x is set to zero.
191 */
192#define get_user(x,ptr) \
193 __get_user_check((x), (ptr), sizeof(*(ptr)))
194
195/*
196 * __put_user: - Write a simple value into user space, with less checking.
197 * @x: Value to copy to user space.
198 * @ptr: Destination address, in user space.
199 *
200 * Context: User context only. This function may sleep if pagefaults are
201 * enabled.
202 *
203 * This macro copies a single simple value from kernel space to user
204 * space. It supports simple types like char and int, but not larger
205 * data types like structures or arrays.
206 *
207 * @ptr must have pointer-to-simple-variable type, and @x must be assignable
208 * to the result of dereferencing @ptr.
209 *
210 * Caller must check the pointer with access_ok() before calling this
211 * function.
212 *
213 * Returns zero on success, or -EFAULT on error.
214 */
215#define __put_user(x,ptr) \
216 __put_user_nocheck((x), (ptr), sizeof(*(ptr)))
217
218/*
219 * __get_user: - Get a simple variable from user space, with less checking.
220 * @x: Variable to store result.
221 * @ptr: Source address, in user space.
222 *
223 * Context: User context only. This function may sleep if pagefaults are
224 * enabled.
225 *
226 * This macro copies a single simple variable from user space to kernel
227 * space. It supports simple types like char and int, but not larger
228 * data types like structures or arrays.
229 *
230 * @ptr must have pointer-to-simple-variable type, and the result of
231 * dereferencing @ptr must be assignable to @x without a cast.
232 *
233 * Caller must check the pointer with access_ok() before calling this
234 * function.
235 *
236 * Returns zero on success, or -EFAULT on error.
237 * On error, the variable @x is set to zero.
238 */
239#define __get_user(x,ptr) \
240 __get_user_nocheck((x), (ptr), sizeof(*(ptr)))
241
242struct __large_struct { unsigned long buf[100]; };
243#define __m(x) (*(struct __large_struct __user *)(x))
244
245/*
246 * Yuck. We need two variants, one for 64bit operation and one
247 * for 32 bit mode and old iron.
248 */
249#ifndef CONFIG_EVA
250#define __get_kernel_common(val, size, ptr) __get_user_common(val, size, ptr)
251#else
252/*
253 * Kernel specific functions for EVA. We need to use normal load instructions
254 * to read data from kernel when operating in EVA mode. We use these macros to
255 * avoid redefining __get_user_asm for EVA.
256 */
257#undef _loadd
258#undef _loadw
259#undef _loadh
260#undef _loadb
261#ifdef CONFIG_32BIT
262#define _loadd _loadw
263#else
264#define _loadd(reg, addr) "ld " reg ", " addr
265#endif
266#define _loadw(reg, addr) "lw " reg ", " addr
267#define _loadh(reg, addr) "lh " reg ", " addr
268#define _loadb(reg, addr) "lb " reg ", " addr
269
270#define __get_kernel_common(val, size, ptr) \
271do { \
272 switch (size) { \
273 case 1: __get_data_asm(val, _loadb, ptr); break; \
274 case 2: __get_data_asm(val, _loadh, ptr); break; \
275 case 4: __get_data_asm(val, _loadw, ptr); break; \
276 case 8: __GET_DW(val, _loadd, ptr); break; \
277 default: __get_user_unknown(); break; \
278 } \
279} while (0)
280#endif
281
282#ifdef CONFIG_32BIT
283#define __GET_DW(val, insn, ptr) __get_data_asm_ll32(val, insn, ptr)
284#endif
285#ifdef CONFIG_64BIT
286#define __GET_DW(val, insn, ptr) __get_data_asm(val, insn, ptr)
287#endif
288
289extern void __get_user_unknown(void);
290
291#define __get_user_common(val, size, ptr) \
292do { \
293 switch (size) { \
294 case 1: __get_data_asm(val, user_lb, ptr); break; \
295 case 2: __get_data_asm(val, user_lh, ptr); break; \
296 case 4: __get_data_asm(val, user_lw, ptr); break; \
297 case 8: __GET_DW(val, user_ld, ptr); break; \
298 default: __get_user_unknown(); break; \
299 } \
300} while (0)
301
302#define __get_user_nocheck(x, ptr, size) \
303({ \
304 int __gu_err; \
305 \
306 if (eva_kernel_access()) { \
307 __get_kernel_common((x), size, ptr); \
308 } else { \
309 __chk_user_ptr(ptr); \
310 __get_user_common((x), size, ptr); \
311 } \
312 __gu_err; \
313})
314
315#define __get_user_check(x, ptr, size) \
316({ \
317 int __gu_err = -EFAULT; \
318 const __typeof__(*(ptr)) __user * __gu_ptr = (ptr); \
319 \
320 might_fault(); \
321 if (likely(access_ok(VERIFY_READ, __gu_ptr, size))) { \
322 if (eva_kernel_access()) \
323 __get_kernel_common((x), size, __gu_ptr); \
324 else \
325 __get_user_common((x), size, __gu_ptr); \
326 } else \
327 (x) = 0; \
328 \
329 __gu_err; \
330})
331
332#define __get_data_asm(val, insn, addr) \
333{ \
334 long __gu_tmp; \
335 \
336 __asm__ __volatile__( \
337 "1: "insn("%1", "%3")" \n" \
338 "2: \n" \
339 " .insn \n" \
340 " .section .fixup,\"ax\" \n" \
341 "3: li %0, %4 \n" \
342 " move %1, $0 \n" \
343 " j 2b \n" \
344 " .previous \n" \
345 " .section __ex_table,\"a\" \n" \
346 " "__UA_ADDR "\t1b, 3b \n" \
347 " .previous \n" \
348 : "=r" (__gu_err), "=r" (__gu_tmp) \
349 : "0" (0), "o" (__m(addr)), "i" (-EFAULT)); \
350 \
351 (val) = (__typeof__(*(addr))) __gu_tmp; \
352}
353
354/*
355 * Get a long long 64 using 32 bit registers.
356 */
357#define __get_data_asm_ll32(val, insn, addr) \
358{ \
359 union { \
360 unsigned long long l; \
361 __typeof__(*(addr)) t; \
362 } __gu_tmp; \
363 \
364 __asm__ __volatile__( \
365 "1: " insn("%1", "(%3)")" \n" \
366 "2: " insn("%D1", "4(%3)")" \n" \
367 "3: \n" \
368 " .insn \n" \
369 " .section .fixup,\"ax\" \n" \
370 "4: li %0, %4 \n" \
371 " move %1, $0 \n" \
372 " move %D1, $0 \n" \
373 " j 3b \n" \
374 " .previous \n" \
375 " .section __ex_table,\"a\" \n" \
376 " " __UA_ADDR " 1b, 4b \n" \
377 " " __UA_ADDR " 2b, 4b \n" \
378 " .previous \n" \
379 : "=r" (__gu_err), "=&r" (__gu_tmp.l) \
380 : "0" (0), "r" (addr), "i" (-EFAULT)); \
381 \
382 (val) = __gu_tmp.t; \
383}
384
385#ifndef CONFIG_EVA
386#define __put_kernel_common(ptr, size) __put_user_common(ptr, size)
387#else
388/*
389 * Kernel specific functions for EVA. We need to use normal load instructions
390 * to read data from kernel when operating in EVA mode. We use these macros to
391 * avoid redefining __get_data_asm for EVA.
392 */
393#undef _stored
394#undef _storew
395#undef _storeh
396#undef _storeb
397#ifdef CONFIG_32BIT
398#define _stored _storew
399#else
400#define _stored(reg, addr) "ld " reg ", " addr
401#endif
402
403#define _storew(reg, addr) "sw " reg ", " addr
404#define _storeh(reg, addr) "sh " reg ", " addr
405#define _storeb(reg, addr) "sb " reg ", " addr
406
407#define __put_kernel_common(ptr, size) \
408do { \
409 switch (size) { \
410 case 1: __put_data_asm(_storeb, ptr); break; \
411 case 2: __put_data_asm(_storeh, ptr); break; \
412 case 4: __put_data_asm(_storew, ptr); break; \
413 case 8: __PUT_DW(_stored, ptr); break; \
414 default: __put_user_unknown(); break; \
415 } \
416} while(0)
417#endif
418
419/*
420 * Yuck. We need two variants, one for 64bit operation and one
421 * for 32 bit mode and old iron.
422 */
423#ifdef CONFIG_32BIT
424#define __PUT_DW(insn, ptr) __put_data_asm_ll32(insn, ptr)
425#endif
426#ifdef CONFIG_64BIT
427#define __PUT_DW(insn, ptr) __put_data_asm(insn, ptr)
428#endif
429
430#define __put_user_common(ptr, size) \
431do { \
432 switch (size) { \
433 case 1: __put_data_asm(user_sb, ptr); break; \
434 case 2: __put_data_asm(user_sh, ptr); break; \
435 case 4: __put_data_asm(user_sw, ptr); break; \
436 case 8: __PUT_DW(user_sd, ptr); break; \
437 default: __put_user_unknown(); break; \
438 } \
439} while (0)
440
441#define __put_user_nocheck(x, ptr, size) \
442({ \
443 __typeof__(*(ptr)) __pu_val; \
444 int __pu_err = 0; \
445 \
446 __pu_val = (x); \
447 if (eva_kernel_access()) { \
448 __put_kernel_common(ptr, size); \
449 } else { \
450 __chk_user_ptr(ptr); \
451 __put_user_common(ptr, size); \
452 } \
453 __pu_err; \
454})
455
456#define __put_user_check(x, ptr, size) \
457({ \
458 __typeof__(*(ptr)) __user *__pu_addr = (ptr); \
459 __typeof__(*(ptr)) __pu_val = (x); \
460 int __pu_err = -EFAULT; \
461 \
462 might_fault(); \
463 if (likely(access_ok(VERIFY_WRITE, __pu_addr, size))) { \
464 if (eva_kernel_access()) \
465 __put_kernel_common(__pu_addr, size); \
466 else \
467 __put_user_common(__pu_addr, size); \
468 } \
469 \
470 __pu_err; \
471})
472
473#define __put_data_asm(insn, ptr) \
474{ \
475 __asm__ __volatile__( \
476 "1: "insn("%z2", "%3")" # __put_data_asm \n" \
477 "2: \n" \
478 " .insn \n" \
479 " .section .fixup,\"ax\" \n" \
480 "3: li %0, %4 \n" \
481 " j 2b \n" \
482 " .previous \n" \
483 " .section __ex_table,\"a\" \n" \
484 " " __UA_ADDR " 1b, 3b \n" \
485 " .previous \n" \
486 : "=r" (__pu_err) \
487 : "0" (0), "Jr" (__pu_val), "o" (__m(ptr)), \
488 "i" (-EFAULT)); \
489}
490
491#define __put_data_asm_ll32(insn, ptr) \
492{ \
493 __asm__ __volatile__( \
494 "1: "insn("%2", "(%3)")" # __put_data_asm_ll32 \n" \
495 "2: "insn("%D2", "4(%3)")" \n" \
496 "3: \n" \
497 " .insn \n" \
498 " .section .fixup,\"ax\" \n" \
499 "4: li %0, %4 \n" \
500 " j 3b \n" \
501 " .previous \n" \
502 " .section __ex_table,\"a\" \n" \
503 " " __UA_ADDR " 1b, 4b \n" \
504 " " __UA_ADDR " 2b, 4b \n" \
505 " .previous" \
506 : "=r" (__pu_err) \
507 : "0" (0), "r" (__pu_val), "r" (ptr), \
508 "i" (-EFAULT)); \
509}
510
511extern void __put_user_unknown(void);
512
513/*
514 * ul{b,h,w} are macros and there are no equivalent macros for EVA.
515 * EVA unaligned access is handled in the ADE exception handler.
516 */
517#ifndef CONFIG_EVA
518/*
519 * put_user_unaligned: - Write a simple value into user space.
520 * @x: Value to copy to user space.
521 * @ptr: Destination address, in user space.
522 *
523 * Context: User context only. This function may sleep if pagefaults are
524 * enabled.
525 *
526 * This macro copies a single simple value from kernel space to user
527 * space. It supports simple types like char and int, but not larger
528 * data types like structures or arrays.
529 *
530 * @ptr must have pointer-to-simple-variable type, and @x must be assignable
531 * to the result of dereferencing @ptr.
532 *
533 * Returns zero on success, or -EFAULT on error.
534 */
535#define put_user_unaligned(x,ptr) \
536 __put_user_unaligned_check((x),(ptr),sizeof(*(ptr)))
537
538/*
539 * get_user_unaligned: - Get a simple variable from user space.
540 * @x: Variable to store result.
541 * @ptr: Source address, in user space.
542 *
543 * Context: User context only. This function may sleep if pagefaults are
544 * enabled.
545 *
546 * This macro copies a single simple variable from user space to kernel
547 * space. It supports simple types like char and int, but not larger
548 * data types like structures or arrays.
549 *
550 * @ptr must have pointer-to-simple-variable type, and the result of
551 * dereferencing @ptr must be assignable to @x without a cast.
552 *
553 * Returns zero on success, or -EFAULT on error.
554 * On error, the variable @x is set to zero.
555 */
556#define get_user_unaligned(x,ptr) \
557 __get_user_unaligned_check((x),(ptr),sizeof(*(ptr)))
558
559/*
560 * __put_user_unaligned: - Write a simple value into user space, with less checking.
561 * @x: Value to copy to user space.
562 * @ptr: Destination address, in user space.
563 *
564 * Context: User context only. This function may sleep if pagefaults are
565 * enabled.
566 *
567 * This macro copies a single simple value from kernel space to user
568 * space. It supports simple types like char and int, but not larger
569 * data types like structures or arrays.
570 *
571 * @ptr must have pointer-to-simple-variable type, and @x must be assignable
572 * to the result of dereferencing @ptr.
573 *
574 * Caller must check the pointer with access_ok() before calling this
575 * function.
576 *
577 * Returns zero on success, or -EFAULT on error.
578 */
579#define __put_user_unaligned(x,ptr) \
580 __put_user_unaligned_nocheck((x),(ptr),sizeof(*(ptr)))
581
582/*
583 * __get_user_unaligned: - Get a simple variable from user space, with less checking.
584 * @x: Variable to store result.
585 * @ptr: Source address, in user space.
586 *
587 * Context: User context only. This function may sleep if pagefaults are
588 * enabled.
589 *
590 * This macro copies a single simple variable from user space to kernel
591 * space. It supports simple types like char and int, but not larger
592 * data types like structures or arrays.
593 *
594 * @ptr must have pointer-to-simple-variable type, and the result of
595 * dereferencing @ptr must be assignable to @x without a cast.
596 *
597 * Caller must check the pointer with access_ok() before calling this
598 * function.
599 *
600 * Returns zero on success, or -EFAULT on error.
601 * On error, the variable @x is set to zero.
602 */
603#define __get_user_unaligned(x,ptr) \
604 __get_user_unaligned_nocheck((x),(ptr),sizeof(*(ptr)))
605
606/*
607 * Yuck. We need two variants, one for 64bit operation and one
608 * for 32 bit mode and old iron.
609 */
610#ifdef CONFIG_32BIT
611#define __GET_USER_UNALIGNED_DW(val, ptr) \
612 __get_user_unaligned_asm_ll32(val, ptr)
613#endif
614#ifdef CONFIG_64BIT
615#define __GET_USER_UNALIGNED_DW(val, ptr) \
616 __get_user_unaligned_asm(val, "uld", ptr)
617#endif
618
619extern void __get_user_unaligned_unknown(void);
620
621#define __get_user_unaligned_common(val, size, ptr) \
622do { \
623 switch (size) { \
624 case 1: __get_data_asm(val, "lb", ptr); break; \
625 case 2: __get_data_unaligned_asm(val, "ulh", ptr); break; \
626 case 4: __get_data_unaligned_asm(val, "ulw", ptr); break; \
627 case 8: __GET_USER_UNALIGNED_DW(val, ptr); break; \
628 default: __get_user_unaligned_unknown(); break; \
629 } \
630} while (0)
631
632#define __get_user_unaligned_nocheck(x,ptr,size) \
633({ \
634 int __gu_err; \
635 \
636 __get_user_unaligned_common((x), size, ptr); \
637 __gu_err; \
638})
639
640#define __get_user_unaligned_check(x,ptr,size) \
641({ \
642 int __gu_err = -EFAULT; \
643 const __typeof__(*(ptr)) __user * __gu_ptr = (ptr); \
644 \
645 if (likely(access_ok(VERIFY_READ, __gu_ptr, size))) \
646 __get_user_unaligned_common((x), size, __gu_ptr); \
647 \
648 __gu_err; \
649})
650
651#define __get_data_unaligned_asm(val, insn, addr) \
652{ \
653 long __gu_tmp; \
654 \
655 __asm__ __volatile__( \
656 "1: " insn " %1, %3 \n" \
657 "2: \n" \
658 " .insn \n" \
659 " .section .fixup,\"ax\" \n" \
660 "3: li %0, %4 \n" \
661 " move %1, $0 \n" \
662 " j 2b \n" \
663 " .previous \n" \
664 " .section __ex_table,\"a\" \n" \
665 " "__UA_ADDR "\t1b, 3b \n" \
666 " "__UA_ADDR "\t1b + 4, 3b \n" \
667 " .previous \n" \
668 : "=r" (__gu_err), "=r" (__gu_tmp) \
669 : "0" (0), "o" (__m(addr)), "i" (-EFAULT)); \
670 \
671 (val) = (__typeof__(*(addr))) __gu_tmp; \
672}
673
674/*
675 * Get a long long 64 using 32 bit registers.
676 */
677#define __get_user_unaligned_asm_ll32(val, addr) \
678{ \
679 unsigned long long __gu_tmp; \
680 \
681 __asm__ __volatile__( \
682 "1: ulw %1, (%3) \n" \
683 "2: ulw %D1, 4(%3) \n" \
684 " move %0, $0 \n" \
685 "3: \n" \
686 " .insn \n" \
687 " .section .fixup,\"ax\" \n" \
688 "4: li %0, %4 \n" \
689 " move %1, $0 \n" \
690 " move %D1, $0 \n" \
691 " j 3b \n" \
692 " .previous \n" \
693 " .section __ex_table,\"a\" \n" \
694 " " __UA_ADDR " 1b, 4b \n" \
695 " " __UA_ADDR " 1b + 4, 4b \n" \
696 " " __UA_ADDR " 2b, 4b \n" \
697 " " __UA_ADDR " 2b + 4, 4b \n" \
698 " .previous \n" \
699 : "=r" (__gu_err), "=&r" (__gu_tmp) \
700 : "0" (0), "r" (addr), "i" (-EFAULT)); \
701 (val) = (__typeof__(*(addr))) __gu_tmp; \
702}
703
704/*
705 * Yuck. We need two variants, one for 64bit operation and one
706 * for 32 bit mode and old iron.
707 */
708#ifdef CONFIG_32BIT
709#define __PUT_USER_UNALIGNED_DW(ptr) __put_user_unaligned_asm_ll32(ptr)
710#endif
711#ifdef CONFIG_64BIT
712#define __PUT_USER_UNALIGNED_DW(ptr) __put_user_unaligned_asm("usd", ptr)
713#endif
714
715#define __put_user_unaligned_common(ptr, size) \
716do { \
717 switch (size) { \
718 case 1: __put_data_asm("sb", ptr); break; \
719 case 2: __put_user_unaligned_asm("ush", ptr); break; \
720 case 4: __put_user_unaligned_asm("usw", ptr); break; \
721 case 8: __PUT_USER_UNALIGNED_DW(ptr); break; \
722 default: __put_user_unaligned_unknown(); break; \
723} while (0)
724
725#define __put_user_unaligned_nocheck(x,ptr,size) \
726({ \
727 __typeof__(*(ptr)) __pu_val; \
728 int __pu_err = 0; \
729 \
730 __pu_val = (x); \
731 __put_user_unaligned_common(ptr, size); \
732 __pu_err; \
733})
734
735#define __put_user_unaligned_check(x,ptr,size) \
736({ \
737 __typeof__(*(ptr)) __user *__pu_addr = (ptr); \
738 __typeof__(*(ptr)) __pu_val = (x); \
739 int __pu_err = -EFAULT; \
740 \
741 if (likely(access_ok(VERIFY_WRITE, __pu_addr, size))) \
742 __put_user_unaligned_common(__pu_addr, size); \
743 \
744 __pu_err; \
745})
746
747#define __put_user_unaligned_asm(insn, ptr) \
748{ \
749 __asm__ __volatile__( \
750 "1: " insn " %z2, %3 # __put_user_unaligned_asm\n" \
751 "2: \n" \
752 " .insn \n" \
753 " .section .fixup,\"ax\" \n" \
754 "3: li %0, %4 \n" \
755 " j 2b \n" \
756 " .previous \n" \
757 " .section __ex_table,\"a\" \n" \
758 " " __UA_ADDR " 1b, 3b \n" \
759 " .previous \n" \
760 : "=r" (__pu_err) \
761 : "0" (0), "Jr" (__pu_val), "o" (__m(ptr)), \
762 "i" (-EFAULT)); \
763}
764
765#define __put_user_unaligned_asm_ll32(ptr) \
766{ \
767 __asm__ __volatile__( \
768 "1: sw %2, (%3) # __put_user_unaligned_asm_ll32 \n" \
769 "2: sw %D2, 4(%3) \n" \
770 "3: \n" \
771 " .insn \n" \
772 " .section .fixup,\"ax\" \n" \
773 "4: li %0, %4 \n" \
774 " j 3b \n" \
775 " .previous \n" \
776 " .section __ex_table,\"a\" \n" \
777 " " __UA_ADDR " 1b, 4b \n" \
778 " " __UA_ADDR " 1b + 4, 4b \n" \
779 " " __UA_ADDR " 2b, 4b \n" \
780 " " __UA_ADDR " 2b + 4, 4b \n" \
781 " .previous" \
782 : "=r" (__pu_err) \
783 : "0" (0), "r" (__pu_val), "r" (ptr), \
784 "i" (-EFAULT)); \
785}
786
787extern void __put_user_unaligned_unknown(void);
788#endif
789
790/*
791 * We're generating jump to subroutines which will be outside the range of
792 * jump instructions
793 */
794#ifdef MODULE
795#define __MODULE_JAL(destination) \
796 ".set\tnoat\n\t" \
797 __UA_LA "\t$1, " #destination "\n\t" \
798 "jalr\t$1\n\t" \
799 ".set\tat\n\t"
800#else
801#define __MODULE_JAL(destination) \
802 "jal\t" #destination "\n\t"
803#endif
804
805#if defined(CONFIG_CPU_DADDI_WORKAROUNDS) || (defined(CONFIG_EVA) && \
806 defined(CONFIG_CPU_HAS_PREFETCH))
807#define DADDI_SCRATCH "$3"
808#else
809#define DADDI_SCRATCH "$0"
810#endif
811
812extern size_t __copy_user(void *__to, const void *__from, size_t __n);
813
814#ifndef CONFIG_EVA
815#define __invoke_copy_to_user(to, from, n) \
816({ \
817 register void __user *__cu_to_r __asm__("$4"); \
818 register const void *__cu_from_r __asm__("$5"); \
819 register long __cu_len_r __asm__("$6"); \
820 \
821 __cu_to_r = (to); \
822 __cu_from_r = (from); \
823 __cu_len_r = (n); \
824 __asm__ __volatile__( \
825 __MODULE_JAL(__copy_user) \
826 : "+r" (__cu_to_r), "+r" (__cu_from_r), "+r" (__cu_len_r) \
827 : \
828 : "$8", "$9", "$10", "$11", "$12", "$14", "$15", "$24", "$31", \
829 DADDI_SCRATCH, "memory"); \
830 __cu_len_r; \
831})
832
833#define __invoke_copy_to_kernel(to, from, n) \
834 __invoke_copy_to_user(to, from, n)
835
836#endif
837
838/*
839 * __copy_to_user: - Copy a block of data into user space, with less checking.
840 * @to: Destination address, in user space.
841 * @from: Source address, in kernel space.
842 * @n: Number of bytes to copy.
843 *
844 * Context: User context only. This function may sleep if pagefaults are
845 * enabled.
846 *
847 * Copy data from kernel space to user space. Caller must check
848 * the specified block with access_ok() before calling this function.
849 *
850 * Returns number of bytes that could not be copied.
851 * On success, this will be zero.
852 */
853#define __copy_to_user(to, from, n) \
854({ \
855 void __user *__cu_to; \
856 const void *__cu_from; \
857 long __cu_len; \
858 \
859 __cu_to = (to); \
860 __cu_from = (from); \
861 __cu_len = (n); \
862 \
863 check_object_size(__cu_from, __cu_len, true); \
864 might_fault(); \
865 \
866 if (eva_kernel_access()) \
867 __cu_len = __invoke_copy_to_kernel(__cu_to, __cu_from, \
868 __cu_len); \
869 else \
870 __cu_len = __invoke_copy_to_user(__cu_to, __cu_from, \
871 __cu_len); \
872 __cu_len; \
873})
874
875extern size_t __copy_user_inatomic(void *__to, const void *__from, size_t __n);
876
877#define __copy_to_user_inatomic(to, from, n) \
878({ \
879 void __user *__cu_to; \
880 const void *__cu_from; \
881 long __cu_len; \
882 \
883 __cu_to = (to); \
884 __cu_from = (from); \
885 __cu_len = (n); \
886 \
887 check_object_size(__cu_from, __cu_len, true); \
888 \
889 if (eva_kernel_access()) \
890 __cu_len = __invoke_copy_to_kernel(__cu_to, __cu_from, \
891 __cu_len); \
892 else \
893 __cu_len = __invoke_copy_to_user(__cu_to, __cu_from, \
894 __cu_len); \
895 __cu_len; \
896})
897
898#define __copy_from_user_inatomic(to, from, n) \
899({ \
900 void *__cu_to; \
901 const void __user *__cu_from; \
902 long __cu_len; \
903 \
904 __cu_to = (to); \
905 __cu_from = (from); \
906 __cu_len = (n); \
907 \
908 check_object_size(__cu_to, __cu_len, false); \
909 \
910 if (eva_kernel_access()) \
911 __cu_len = __invoke_copy_from_kernel_inatomic(__cu_to, \
912 __cu_from,\
913 __cu_len);\
914 else \
915 __cu_len = __invoke_copy_from_user_inatomic(__cu_to, \
916 __cu_from, \
917 __cu_len); \
918 __cu_len; \
919})
920
921/*
922 * copy_to_user: - Copy a block of data into user space.
923 * @to: Destination address, in user space.
924 * @from: Source address, in kernel space.
925 * @n: Number of bytes to copy.
926 *
927 * Context: User context only. This function may sleep if pagefaults are
928 * enabled.
929 *
930 * Copy data from kernel space to user space.
931 *
932 * Returns number of bytes that could not be copied.
933 * On success, this will be zero.
934 */
935#define copy_to_user(to, from, n) \
936({ \
937 void __user *__cu_to; \
938 const void *__cu_from; \
939 long __cu_len; \
940 \
941 __cu_to = (to); \
942 __cu_from = (from); \
943 __cu_len = (n); \
944 \
945 check_object_size(__cu_from, __cu_len, true); \
946 \
947 if (eva_kernel_access()) { \
948 __cu_len = __invoke_copy_to_kernel(__cu_to, \
949 __cu_from, \
950 __cu_len); \
951 } else { \
952 if (access_ok(VERIFY_WRITE, __cu_to, __cu_len)) { \
953 might_fault(); \
954 __cu_len = __invoke_copy_to_user(__cu_to, \
955 __cu_from, \
956 __cu_len); \
957 } \
958 } \
959 __cu_len; \
960})
961
962#ifndef CONFIG_EVA
963
964#define __invoke_copy_from_user(to, from, n) \
965({ \
966 register void *__cu_to_r __asm__("$4"); \
967 register const void __user *__cu_from_r __asm__("$5"); \
968 register long __cu_len_r __asm__("$6"); \
969 \
970 __cu_to_r = (to); \
971 __cu_from_r = (from); \
972 __cu_len_r = (n); \
973 __asm__ __volatile__( \
974 ".set\tnoreorder\n\t" \
975 __MODULE_JAL(__copy_user) \
976 ".set\tnoat\n\t" \
977 __UA_ADDU "\t$1, %1, %2\n\t" \
978 ".set\tat\n\t" \
979 ".set\treorder" \
980 : "+r" (__cu_to_r), "+r" (__cu_from_r), "+r" (__cu_len_r) \
981 : \
982 : "$8", "$9", "$10", "$11", "$12", "$14", "$15", "$24", "$31", \
983 DADDI_SCRATCH, "memory"); \
984 __cu_len_r; \
985})
986
987#define __invoke_copy_from_kernel(to, from, n) \
988 __invoke_copy_from_user(to, from, n)
989
990/* For userland <-> userland operations */
991#define ___invoke_copy_in_user(to, from, n) \
992 __invoke_copy_from_user(to, from, n)
993
994/* For kernel <-> kernel operations */
995#define ___invoke_copy_in_kernel(to, from, n) \
996 __invoke_copy_from_user(to, from, n)
997
998#define __invoke_copy_from_user_inatomic(to, from, n) \
999({ \
1000 register void *__cu_to_r __asm__("$4"); \
1001 register const void __user *__cu_from_r __asm__("$5"); \
1002 register long __cu_len_r __asm__("$6"); \
1003 \
1004 __cu_to_r = (to); \
1005 __cu_from_r = (from); \
1006 __cu_len_r = (n); \
1007 __asm__ __volatile__( \
1008 ".set\tnoreorder\n\t" \
1009 __MODULE_JAL(__copy_user_inatomic) \
1010 ".set\tnoat\n\t" \
1011 __UA_ADDU "\t$1, %1, %2\n\t" \
1012 ".set\tat\n\t" \
1013 ".set\treorder" \
1014 : "+r" (__cu_to_r), "+r" (__cu_from_r), "+r" (__cu_len_r) \
1015 : \
1016 : "$8", "$9", "$10", "$11", "$12", "$14", "$15", "$24", "$31", \
1017 DADDI_SCRATCH, "memory"); \
1018 __cu_len_r; \
1019})
1020
1021#define __invoke_copy_from_kernel_inatomic(to, from, n) \
1022 __invoke_copy_from_user_inatomic(to, from, n) \
1023
1024#else
1025
1026/* EVA specific functions */
1027
1028extern size_t __copy_user_inatomic_eva(void *__to, const void *__from,
1029 size_t __n);
1030extern size_t __copy_from_user_eva(void *__to, const void *__from,
1031 size_t __n);
1032extern size_t __copy_to_user_eva(void *__to, const void *__from,
1033 size_t __n);
1034extern size_t __copy_in_user_eva(void *__to, const void *__from, size_t __n);
1035
1036#define __invoke_copy_from_user_eva_generic(to, from, n, func_ptr) \
1037({ \
1038 register void *__cu_to_r __asm__("$4"); \
1039 register const void __user *__cu_from_r __asm__("$5"); \
1040 register long __cu_len_r __asm__("$6"); \
1041 \
1042 __cu_to_r = (to); \
1043 __cu_from_r = (from); \
1044 __cu_len_r = (n); \
1045 __asm__ __volatile__( \
1046 ".set\tnoreorder\n\t" \
1047 __MODULE_JAL(func_ptr) \
1048 ".set\tnoat\n\t" \
1049 __UA_ADDU "\t$1, %1, %2\n\t" \
1050 ".set\tat\n\t" \
1051 ".set\treorder" \
1052 : "+r" (__cu_to_r), "+r" (__cu_from_r), "+r" (__cu_len_r) \
1053 : \
1054 : "$8", "$9", "$10", "$11", "$12", "$14", "$15", "$24", "$31", \
1055 DADDI_SCRATCH, "memory"); \
1056 __cu_len_r; \
1057})
1058
1059#define __invoke_copy_to_user_eva_generic(to, from, n, func_ptr) \
1060({ \
1061 register void *__cu_to_r __asm__("$4"); \
1062 register const void __user *__cu_from_r __asm__("$5"); \
1063 register long __cu_len_r __asm__("$6"); \
1064 \
1065 __cu_to_r = (to); \
1066 __cu_from_r = (from); \
1067 __cu_len_r = (n); \
1068 __asm__ __volatile__( \
1069 __MODULE_JAL(func_ptr) \
1070 : "+r" (__cu_to_r), "+r" (__cu_from_r), "+r" (__cu_len_r) \
1071 : \
1072 : "$8", "$9", "$10", "$11", "$12", "$14", "$15", "$24", "$31", \
1073 DADDI_SCRATCH, "memory"); \
1074 __cu_len_r; \
1075})
1076
1077/*
1078 * Source or destination address is in userland. We need to go through
1079 * the TLB
1080 */
1081#define __invoke_copy_from_user(to, from, n) \
1082 __invoke_copy_from_user_eva_generic(to, from, n, __copy_from_user_eva)
1083
1084#define __invoke_copy_from_user_inatomic(to, from, n) \
1085 __invoke_copy_from_user_eva_generic(to, from, n, \
1086 __copy_user_inatomic_eva)
1087
1088#define __invoke_copy_to_user(to, from, n) \
1089 __invoke_copy_to_user_eva_generic(to, from, n, __copy_to_user_eva)
1090
1091#define ___invoke_copy_in_user(to, from, n) \
1092 __invoke_copy_from_user_eva_generic(to, from, n, __copy_in_user_eva)
1093
1094/*
1095 * Source or destination address in the kernel. We are not going through
1096 * the TLB
1097 */
1098#define __invoke_copy_from_kernel(to, from, n) \
1099 __invoke_copy_from_user_eva_generic(to, from, n, __copy_user)
1100
1101#define __invoke_copy_from_kernel_inatomic(to, from, n) \
1102 __invoke_copy_from_user_eva_generic(to, from, n, __copy_user_inatomic)
1103
1104#define __invoke_copy_to_kernel(to, from, n) \
1105 __invoke_copy_to_user_eva_generic(to, from, n, __copy_user)
1106
1107#define ___invoke_copy_in_kernel(to, from, n) \
1108 __invoke_copy_from_user_eva_generic(to, from, n, __copy_user)
1109
1110#endif /* CONFIG_EVA */
1111
1112/*
1113 * __copy_from_user: - Copy a block of data from user space, with less checking.
1114 * @to: Destination address, in kernel space.
1115 * @from: Source address, in user space.
1116 * @n: Number of bytes to copy.
1117 *
1118 * Context: User context only. This function may sleep if pagefaults are
1119 * enabled.
1120 *
1121 * Copy data from user space to kernel space. Caller must check
1122 * the specified block with access_ok() before calling this function.
1123 *
1124 * Returns number of bytes that could not be copied.
1125 * On success, this will be zero.
1126 *
1127 * If some data could not be copied, this function will pad the copied
1128 * data to the requested size using zero bytes.
1129 */
1130#define __copy_from_user(to, from, n) \
1131({ \
1132 void *__cu_to; \
1133 const void __user *__cu_from; \
1134 long __cu_len; \
1135 \
1136 __cu_to = (to); \
1137 __cu_from = (from); \
1138 __cu_len = (n); \
1139 \
1140 check_object_size(__cu_to, __cu_len, false); \
1141 \
1142 if (eva_kernel_access()) { \
1143 __cu_len = __invoke_copy_from_kernel(__cu_to, \
1144 __cu_from, \
1145 __cu_len); \
1146 } else { \
1147 might_fault(); \
1148 __cu_len = __invoke_copy_from_user(__cu_to, __cu_from, \
1149 __cu_len); \
1150 } \
1151 __cu_len; \
1152})
1153
1154/*
1155 * copy_from_user: - Copy a block of data from user space.
1156 * @to: Destination address, in kernel space.
1157 * @from: Source address, in user space.
1158 * @n: Number of bytes to copy.
1159 *
1160 * Context: User context only. This function may sleep if pagefaults are
1161 * enabled.
1162 *
1163 * Copy data from user space to kernel space.
1164 *
1165 * Returns number of bytes that could not be copied.
1166 * On success, this will be zero.
1167 *
1168 * If some data could not be copied, this function will pad the copied
1169 * data to the requested size using zero bytes.
1170 */
1171#define copy_from_user(to, from, n) \
1172({ \
1173 void *__cu_to; \
1174 const void __user *__cu_from; \
1175 long __cu_len; \
1176 \
1177 __cu_to = (to); \
1178 __cu_from = (from); \
1179 __cu_len = (n); \
1180 \
1181 check_object_size(__cu_to, __cu_len, false); \
1182 \
1183 if (eva_kernel_access()) { \
1184 __cu_len = __invoke_copy_from_kernel(__cu_to, \
1185 __cu_from, \
1186 __cu_len); \
1187 } else { \
1188 if (access_ok(VERIFY_READ, __cu_from, __cu_len)) { \
1189 might_fault(); \
1190 __cu_len = __invoke_copy_from_user(__cu_to, \
1191 __cu_from, \
1192 __cu_len); \
1193 } else { \
1194 memset(__cu_to, 0, __cu_len); \
1195 } \
1196 } \
1197 __cu_len; \
1198})
1199
1200#define __copy_in_user(to, from, n) \
1201({ \
1202 void __user *__cu_to; \
1203 const void __user *__cu_from; \
1204 long __cu_len; \
1205 \
1206 __cu_to = (to); \
1207 __cu_from = (from); \
1208 __cu_len = (n); \
1209 if (eva_kernel_access()) { \
1210 __cu_len = ___invoke_copy_in_kernel(__cu_to, __cu_from, \
1211 __cu_len); \
1212 } else { \
1213 might_fault(); \
1214 __cu_len = ___invoke_copy_in_user(__cu_to, __cu_from, \
1215 __cu_len); \
1216 } \
1217 __cu_len; \
1218})
1219
1220#define copy_in_user(to, from, n) \
1221({ \
1222 void __user *__cu_to; \
1223 const void __user *__cu_from; \
1224 long __cu_len; \
1225 \
1226 __cu_to = (to); \
1227 __cu_from = (from); \
1228 __cu_len = (n); \
1229 if (eva_kernel_access()) { \
1230 __cu_len = ___invoke_copy_in_kernel(__cu_to,__cu_from, \
1231 __cu_len); \
1232 } else { \
1233 if (likely(access_ok(VERIFY_READ, __cu_from, __cu_len) &&\
1234 access_ok(VERIFY_WRITE, __cu_to, __cu_len))) {\
1235 might_fault(); \
1236 __cu_len = ___invoke_copy_in_user(__cu_to, \
1237 __cu_from, \
1238 __cu_len); \
1239 } \
1240 } \
1241 __cu_len; \
1242})
1243
1244/*
1245 * __clear_user: - Zero a block of memory in user space, with less checking.
1246 * @to: Destination address, in user space.
1247 * @n: Number of bytes to zero.
1248 *
1249 * Zero a block of memory in user space. Caller must check
1250 * the specified block with access_ok() before calling this function.
1251 *
1252 * Returns number of bytes that could not be cleared.
1253 * On success, this will be zero.
1254 */
1255static inline __kernel_size_t
1256__clear_user(void __user *addr, __kernel_size_t size)
1257{
1258 __kernel_size_t res;
1259
1260 if (eva_kernel_access()) {
1261 __asm__ __volatile__(
1262 "move\t$4, %1\n\t"
1263 "move\t$5, $0\n\t"
1264 "move\t$6, %2\n\t"
1265 __MODULE_JAL(__bzero_kernel)
1266 "move\t%0, $6"
1267 : "=r" (res)
1268 : "r" (addr), "r" (size)
1269 : "$4", "$5", "$6", __UA_t0, __UA_t1, "$31");
1270 } else {
1271 might_fault();
1272 __asm__ __volatile__(
1273 "move\t$4, %1\n\t"
1274 "move\t$5, $0\n\t"
1275 "move\t$6, %2\n\t"
1276 __MODULE_JAL(__bzero)
1277 "move\t%0, $6"
1278 : "=r" (res)
1279 : "r" (addr), "r" (size)
1280 : "$4", "$5", "$6", __UA_t0, __UA_t1, "$31");
1281 }
1282
1283 return res;
1284}
1285
1286#define clear_user(addr,n) \
1287({ \
1288 void __user * __cl_addr = (addr); \
1289 unsigned long __cl_size = (n); \
1290 if (__cl_size && access_ok(VERIFY_WRITE, \
1291 __cl_addr, __cl_size)) \
1292 __cl_size = __clear_user(__cl_addr, __cl_size); \
1293 __cl_size; \
1294})
1295
1296/*
1297 * __strncpy_from_user: - Copy a NUL terminated string from userspace, with less checking.
1298 * @dst: Destination address, in kernel space. This buffer must be at
1299 * least @count bytes long.
1300 * @src: Source address, in user space.
1301 * @count: Maximum number of bytes to copy, including the trailing NUL.
1302 *
1303 * Copies a NUL-terminated string from userspace to kernel space.
1304 * Caller must check the specified block with access_ok() before calling
1305 * this function.
1306 *
1307 * On success, returns the length of the string (not including the trailing
1308 * NUL).
1309 *
1310 * If access to userspace fails, returns -EFAULT (some data may have been
1311 * copied).
1312 *
1313 * If @count is smaller than the length of the string, copies @count bytes
1314 * and returns @count.
1315 */
1316static inline long
1317__strncpy_from_user(char *__to, const char __user *__from, long __len)
1318{
1319 long res;
1320
1321 if (eva_kernel_access()) {
1322 __asm__ __volatile__(
1323 "move\t$4, %1\n\t"
1324 "move\t$5, %2\n\t"
1325 "move\t$6, %3\n\t"
1326 __MODULE_JAL(__strncpy_from_kernel_nocheck_asm)
1327 "move\t%0, $2"
1328 : "=r" (res)
1329 : "r" (__to), "r" (__from), "r" (__len)
1330 : "$2", "$3", "$4", "$5", "$6", __UA_t0, "$31", "memory");
1331 } else {
1332 might_fault();
1333 __asm__ __volatile__(
1334 "move\t$4, %1\n\t"
1335 "move\t$5, %2\n\t"
1336 "move\t$6, %3\n\t"
1337 __MODULE_JAL(__strncpy_from_user_nocheck_asm)
1338 "move\t%0, $2"
1339 : "=r" (res)
1340 : "r" (__to), "r" (__from), "r" (__len)
1341 : "$2", "$3", "$4", "$5", "$6", __UA_t0, "$31", "memory");
1342 }
1343
1344 return res;
1345}
1346
1347/*
1348 * strncpy_from_user: - Copy a NUL terminated string from userspace.
1349 * @dst: Destination address, in kernel space. This buffer must be at
1350 * least @count bytes long.
1351 * @src: Source address, in user space.
1352 * @count: Maximum number of bytes to copy, including the trailing NUL.
1353 *
1354 * Copies a NUL-terminated string from userspace to kernel space.
1355 *
1356 * On success, returns the length of the string (not including the trailing
1357 * NUL).
1358 *
1359 * If access to userspace fails, returns -EFAULT (some data may have been
1360 * copied).
1361 *
1362 * If @count is smaller than the length of the string, copies @count bytes
1363 * and returns @count.
1364 */
1365static inline long
1366strncpy_from_user(char *__to, const char __user *__from, long __len)
1367{
1368 long res;
1369
1370 if (eva_kernel_access()) {
1371 __asm__ __volatile__(
1372 "move\t$4, %1\n\t"
1373 "move\t$5, %2\n\t"
1374 "move\t$6, %3\n\t"
1375 __MODULE_JAL(__strncpy_from_kernel_asm)
1376 "move\t%0, $2"
1377 : "=r" (res)
1378 : "r" (__to), "r" (__from), "r" (__len)
1379 : "$2", "$3", "$4", "$5", "$6", __UA_t0, "$31", "memory");
1380 } else {
1381 might_fault();
1382 __asm__ __volatile__(
1383 "move\t$4, %1\n\t"
1384 "move\t$5, %2\n\t"
1385 "move\t$6, %3\n\t"
1386 __MODULE_JAL(__strncpy_from_user_asm)
1387 "move\t%0, $2"
1388 : "=r" (res)
1389 : "r" (__to), "r" (__from), "r" (__len)
1390 : "$2", "$3", "$4", "$5", "$6", __UA_t0, "$31", "memory");
1391 }
1392
1393 return res;
1394}
1395
1396/*
1397 * strlen_user: - Get the size of a string in user space.
1398 * @str: The string to measure.
1399 *
1400 * Context: User context only. This function may sleep if pagefaults are
1401 * enabled.
1402 *
1403 * Get the size of a NUL-terminated string in user space.
1404 *
1405 * Returns the size of the string INCLUDING the terminating NUL.
1406 * On exception, returns 0.
1407 *
1408 * If there is a limit on the length of a valid string, you may wish to
1409 * consider using strnlen_user() instead.
1410 */
1411static inline long strlen_user(const char __user *s)
1412{
1413 long res;
1414
1415 if (eva_kernel_access()) {
1416 __asm__ __volatile__(
1417 "move\t$4, %1\n\t"
1418 __MODULE_JAL(__strlen_kernel_asm)
1419 "move\t%0, $2"
1420 : "=r" (res)
1421 : "r" (s)
1422 : "$2", "$4", __UA_t0, "$31");
1423 } else {
1424 might_fault();
1425 __asm__ __volatile__(
1426 "move\t$4, %1\n\t"
1427 __MODULE_JAL(__strlen_user_asm)
1428 "move\t%0, $2"
1429 : "=r" (res)
1430 : "r" (s)
1431 : "$2", "$4", __UA_t0, "$31");
1432 }
1433
1434 return res;
1435}
1436
1437/* Returns: 0 if bad, string length+1 (memory size) of string if ok */
1438static inline long __strnlen_user(const char __user *s, long n)
1439{
1440 long res;
1441
1442 if (eva_kernel_access()) {
1443 __asm__ __volatile__(
1444 "move\t$4, %1\n\t"
1445 "move\t$5, %2\n\t"
1446 __MODULE_JAL(__strnlen_kernel_nocheck_asm)
1447 "move\t%0, $2"
1448 : "=r" (res)
1449 : "r" (s), "r" (n)
1450 : "$2", "$4", "$5", __UA_t0, "$31");
1451 } else {
1452 might_fault();
1453 __asm__ __volatile__(
1454 "move\t$4, %1\n\t"
1455 "move\t$5, %2\n\t"
1456 __MODULE_JAL(__strnlen_user_nocheck_asm)
1457 "move\t%0, $2"
1458 : "=r" (res)
1459 : "r" (s), "r" (n)
1460 : "$2", "$4", "$5", __UA_t0, "$31");
1461 }
1462
1463 return res;
1464}
1465
1466/*
1467 * strnlen_user: - Get the size of a string in user space.
1468 * @str: The string to measure.
1469 *
1470 * Context: User context only. This function may sleep if pagefaults are
1471 * enabled.
1472 *
1473 * Get the size of a NUL-terminated string in user space.
1474 *
1475 * Returns the size of the string INCLUDING the terminating NUL.
1476 * On exception, returns 0.
1477 * If the string is too long, returns a value greater than @n.
1478 */
1479static inline long strnlen_user(const char __user *s, long n)
1480{
1481 long res;
1482
1483 might_fault();
1484 if (eva_kernel_access()) {
1485 __asm__ __volatile__(
1486 "move\t$4, %1\n\t"
1487 "move\t$5, %2\n\t"
1488 __MODULE_JAL(__strnlen_kernel_asm)
1489 "move\t%0, $2"
1490 : "=r" (res)
1491 : "r" (s), "r" (n)
1492 : "$2", "$4", "$5", __UA_t0, "$31");
1493 } else {
1494 __asm__ __volatile__(
1495 "move\t$4, %1\n\t"
1496 "move\t$5, %2\n\t"
1497 __MODULE_JAL(__strnlen_user_asm)
1498 "move\t%0, $2"
1499 : "=r" (res)
1500 : "r" (s), "r" (n)
1501 : "$2", "$4", "$5", __UA_t0, "$31");
1502 }
1503
1504 return res;
1505}
1506
1507#endif /* _ASM_UACCESS_H */