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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dledford/rdma
[deliverable/linux.git] / arch / mips / include / 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
44 extern 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 * eva_kernel_access() - determine whether kernel memory access on an EVA system
83 *
84 * Determines whether memory accesses should be performed to kernel memory
85 * on a system using Extended Virtual Addressing (EVA).
86 *
87 * Return: true if a kernel memory access on an EVA system, else false.
88 */
89 static inline bool eva_kernel_access(void)
90 {
91 if (!config_enabled(CONFIG_EVA))
92 return false;
93
94 return segment_eq(get_fs(), get_ds());
95 }
96
97 /*
98 * Is a address valid? This does a straightforward calculation rather
99 * than tests.
100 *
101 * Address valid if:
102 * - "addr" doesn't have any high-bits set
103 * - AND "size" doesn't have any high-bits set
104 * - AND "addr+size" doesn't have any high-bits set
105 * - OR we are in kernel mode.
106 *
107 * __ua_size() is a trick to avoid runtime checking of positive constant
108 * sizes; for those we already know at compile time that the size is ok.
109 */
110 #define __ua_size(size) \
111 ((__builtin_constant_p(size) && (signed long) (size) > 0) ? 0 : (size))
112
113 /*
114 * access_ok: - Checks if a user space pointer is valid
115 * @type: Type of access: %VERIFY_READ or %VERIFY_WRITE. Note that
116 * %VERIFY_WRITE is a superset of %VERIFY_READ - if it is safe
117 * to write to a block, it is always safe to read from it.
118 * @addr: User space pointer to start of block to check
119 * @size: Size of block to check
120 *
121 * Context: User context only. This function may sleep if pagefaults are
122 * enabled.
123 *
124 * Checks if a pointer to a block of memory in user space is valid.
125 *
126 * Returns true (nonzero) if the memory block may be valid, false (zero)
127 * if it is definitely invalid.
128 *
129 * Note that, depending on architecture, this function probably just
130 * checks that the pointer is in the user space range - after calling
131 * this function, memory access functions may still return -EFAULT.
132 */
133
134 #define __access_mask get_fs().seg
135
136 #define __access_ok(addr, size, mask) \
137 ({ \
138 unsigned long __addr = (unsigned long) (addr); \
139 unsigned long __size = size; \
140 unsigned long __mask = mask; \
141 unsigned long __ok; \
142 \
143 __chk_user_ptr(addr); \
144 __ok = (signed long)(__mask & (__addr | (__addr + __size) | \
145 __ua_size(__size))); \
146 __ok == 0; \
147 })
148
149 #define access_ok(type, addr, size) \
150 likely(__access_ok((addr), (size), __access_mask))
151
152 /*
153 * put_user: - Write a simple value into user space.
154 * @x: Value to copy to user space.
155 * @ptr: Destination address, in user space.
156 *
157 * Context: User context only. This function may sleep if pagefaults are
158 * enabled.
159 *
160 * This macro copies a single simple value from kernel space to user
161 * space. It supports simple types like char and int, but not larger
162 * data types like structures or arrays.
163 *
164 * @ptr must have pointer-to-simple-variable type, and @x must be assignable
165 * to the result of dereferencing @ptr.
166 *
167 * Returns zero on success, or -EFAULT on error.
168 */
169 #define put_user(x,ptr) \
170 __put_user_check((x), (ptr), sizeof(*(ptr)))
171
172 /*
173 * get_user: - Get a simple variable from user space.
174 * @x: Variable to store result.
175 * @ptr: Source address, in user space.
176 *
177 * Context: User context only. This function may sleep if pagefaults are
178 * enabled.
179 *
180 * This macro copies a single simple variable from user space to kernel
181 * space. It supports simple types like char and int, but not larger
182 * data types like structures or arrays.
183 *
184 * @ptr must have pointer-to-simple-variable type, and the result of
185 * dereferencing @ptr must be assignable to @x without a cast.
186 *
187 * Returns zero on success, or -EFAULT on error.
188 * On error, the variable @x is set to zero.
189 */
190 #define get_user(x,ptr) \
191 __get_user_check((x), (ptr), sizeof(*(ptr)))
192
193 /*
194 * __put_user: - Write a simple value into user space, with less checking.
195 * @x: Value to copy to user space.
196 * @ptr: Destination address, in user space.
197 *
198 * Context: User context only. This function may sleep if pagefaults are
199 * enabled.
200 *
201 * This macro copies a single simple value from kernel space to user
202 * space. It supports simple types like char and int, but not larger
203 * data types like structures or arrays.
204 *
205 * @ptr must have pointer-to-simple-variable type, and @x must be assignable
206 * to the result of dereferencing @ptr.
207 *
208 * Caller must check the pointer with access_ok() before calling this
209 * function.
210 *
211 * Returns zero on success, or -EFAULT on error.
212 */
213 #define __put_user(x,ptr) \
214 __put_user_nocheck((x), (ptr), sizeof(*(ptr)))
215
216 /*
217 * __get_user: - Get a simple variable from user space, with less checking.
218 * @x: Variable to store result.
219 * @ptr: Source address, in user space.
220 *
221 * Context: User context only. This function may sleep if pagefaults are
222 * enabled.
223 *
224 * This macro copies a single simple variable from user space to kernel
225 * space. It supports simple types like char and int, but not larger
226 * data types like structures or arrays.
227 *
228 * @ptr must have pointer-to-simple-variable type, and the result of
229 * dereferencing @ptr must be assignable to @x without a cast.
230 *
231 * Caller must check the pointer with access_ok() before calling this
232 * function.
233 *
234 * Returns zero on success, or -EFAULT on error.
235 * On error, the variable @x is set to zero.
236 */
237 #define __get_user(x,ptr) \
238 __get_user_nocheck((x), (ptr), sizeof(*(ptr)))
239
240 struct __large_struct { unsigned long buf[100]; };
241 #define __m(x) (*(struct __large_struct __user *)(x))
242
243 /*
244 * Yuck. We need two variants, one for 64bit operation and one
245 * for 32 bit mode and old iron.
246 */
247 #ifndef CONFIG_EVA
248 #define __get_kernel_common(val, size, ptr) __get_user_common(val, size, ptr)
249 #else
250 /*
251 * Kernel specific functions for EVA. We need to use normal load instructions
252 * to read data from kernel when operating in EVA mode. We use these macros to
253 * avoid redefining __get_user_asm for EVA.
254 */
255 #undef _loadd
256 #undef _loadw
257 #undef _loadh
258 #undef _loadb
259 #ifdef CONFIG_32BIT
260 #define _loadd _loadw
261 #else
262 #define _loadd(reg, addr) "ld " reg ", " addr
263 #endif
264 #define _loadw(reg, addr) "lw " reg ", " addr
265 #define _loadh(reg, addr) "lh " reg ", " addr
266 #define _loadb(reg, addr) "lb " reg ", " addr
267
268 #define __get_kernel_common(val, size, ptr) \
269 do { \
270 switch (size) { \
271 case 1: __get_data_asm(val, _loadb, ptr); break; \
272 case 2: __get_data_asm(val, _loadh, ptr); break; \
273 case 4: __get_data_asm(val, _loadw, ptr); break; \
274 case 8: __GET_DW(val, _loadd, ptr); break; \
275 default: __get_user_unknown(); break; \
276 } \
277 } while (0)
278 #endif
279
280 #ifdef CONFIG_32BIT
281 #define __GET_DW(val, insn, ptr) __get_data_asm_ll32(val, insn, ptr)
282 #endif
283 #ifdef CONFIG_64BIT
284 #define __GET_DW(val, insn, ptr) __get_data_asm(val, insn, ptr)
285 #endif
286
287 extern void __get_user_unknown(void);
288
289 #define __get_user_common(val, size, ptr) \
290 do { \
291 switch (size) { \
292 case 1: __get_data_asm(val, user_lb, ptr); break; \
293 case 2: __get_data_asm(val, user_lh, ptr); break; \
294 case 4: __get_data_asm(val, user_lw, ptr); break; \
295 case 8: __GET_DW(val, user_ld, ptr); break; \
296 default: __get_user_unknown(); break; \
297 } \
298 } while (0)
299
300 #define __get_user_nocheck(x, ptr, size) \
301 ({ \
302 int __gu_err; \
303 \
304 if (eva_kernel_access()) { \
305 __get_kernel_common((x), size, ptr); \
306 } else { \
307 __chk_user_ptr(ptr); \
308 __get_user_common((x), size, ptr); \
309 } \
310 __gu_err; \
311 })
312
313 #define __get_user_check(x, ptr, size) \
314 ({ \
315 int __gu_err = -EFAULT; \
316 const __typeof__(*(ptr)) __user * __gu_ptr = (ptr); \
317 \
318 might_fault(); \
319 if (likely(access_ok(VERIFY_READ, __gu_ptr, size))) { \
320 if (eva_kernel_access()) \
321 __get_kernel_common((x), size, __gu_ptr); \
322 else \
323 __get_user_common((x), size, __gu_ptr); \
324 } else \
325 (x) = 0; \
326 \
327 __gu_err; \
328 })
329
330 #define __get_data_asm(val, insn, addr) \
331 { \
332 long __gu_tmp; \
333 \
334 __asm__ __volatile__( \
335 "1: "insn("%1", "%3")" \n" \
336 "2: \n" \
337 " .insn \n" \
338 " .section .fixup,\"ax\" \n" \
339 "3: li %0, %4 \n" \
340 " move %1, $0 \n" \
341 " j 2b \n" \
342 " .previous \n" \
343 " .section __ex_table,\"a\" \n" \
344 " "__UA_ADDR "\t1b, 3b \n" \
345 " .previous \n" \
346 : "=r" (__gu_err), "=r" (__gu_tmp) \
347 : "0" (0), "o" (__m(addr)), "i" (-EFAULT)); \
348 \
349 (val) = (__typeof__(*(addr))) __gu_tmp; \
350 }
351
352 /*
353 * Get a long long 64 using 32 bit registers.
354 */
355 #define __get_data_asm_ll32(val, insn, addr) \
356 { \
357 union { \
358 unsigned long long l; \
359 __typeof__(*(addr)) t; \
360 } __gu_tmp; \
361 \
362 __asm__ __volatile__( \
363 "1: " insn("%1", "(%3)")" \n" \
364 "2: " insn("%D1", "4(%3)")" \n" \
365 "3: \n" \
366 " .insn \n" \
367 " .section .fixup,\"ax\" \n" \
368 "4: li %0, %4 \n" \
369 " move %1, $0 \n" \
370 " move %D1, $0 \n" \
371 " j 3b \n" \
372 " .previous \n" \
373 " .section __ex_table,\"a\" \n" \
374 " " __UA_ADDR " 1b, 4b \n" \
375 " " __UA_ADDR " 2b, 4b \n" \
376 " .previous \n" \
377 : "=r" (__gu_err), "=&r" (__gu_tmp.l) \
378 : "0" (0), "r" (addr), "i" (-EFAULT)); \
379 \
380 (val) = __gu_tmp.t; \
381 }
382
383 #ifndef CONFIG_EVA
384 #define __put_kernel_common(ptr, size) __put_user_common(ptr, size)
385 #else
386 /*
387 * Kernel specific functions for EVA. We need to use normal load instructions
388 * to read data from kernel when operating in EVA mode. We use these macros to
389 * avoid redefining __get_data_asm for EVA.
390 */
391 #undef _stored
392 #undef _storew
393 #undef _storeh
394 #undef _storeb
395 #ifdef CONFIG_32BIT
396 #define _stored _storew
397 #else
398 #define _stored(reg, addr) "ld " reg ", " addr
399 #endif
400
401 #define _storew(reg, addr) "sw " reg ", " addr
402 #define _storeh(reg, addr) "sh " reg ", " addr
403 #define _storeb(reg, addr) "sb " reg ", " addr
404
405 #define __put_kernel_common(ptr, size) \
406 do { \
407 switch (size) { \
408 case 1: __put_data_asm(_storeb, ptr); break; \
409 case 2: __put_data_asm(_storeh, ptr); break; \
410 case 4: __put_data_asm(_storew, ptr); break; \
411 case 8: __PUT_DW(_stored, ptr); break; \
412 default: __put_user_unknown(); break; \
413 } \
414 } while(0)
415 #endif
416
417 /*
418 * Yuck. We need two variants, one for 64bit operation and one
419 * for 32 bit mode and old iron.
420 */
421 #ifdef CONFIG_32BIT
422 #define __PUT_DW(insn, ptr) __put_data_asm_ll32(insn, ptr)
423 #endif
424 #ifdef CONFIG_64BIT
425 #define __PUT_DW(insn, ptr) __put_data_asm(insn, ptr)
426 #endif
427
428 #define __put_user_common(ptr, size) \
429 do { \
430 switch (size) { \
431 case 1: __put_data_asm(user_sb, ptr); break; \
432 case 2: __put_data_asm(user_sh, ptr); break; \
433 case 4: __put_data_asm(user_sw, ptr); break; \
434 case 8: __PUT_DW(user_sd, ptr); break; \
435 default: __put_user_unknown(); break; \
436 } \
437 } while (0)
438
439 #define __put_user_nocheck(x, ptr, size) \
440 ({ \
441 __typeof__(*(ptr)) __pu_val; \
442 int __pu_err = 0; \
443 \
444 __pu_val = (x); \
445 if (eva_kernel_access()) { \
446 __put_kernel_common(ptr, size); \
447 } else { \
448 __chk_user_ptr(ptr); \
449 __put_user_common(ptr, size); \
450 } \
451 __pu_err; \
452 })
453
454 #define __put_user_check(x, ptr, size) \
455 ({ \
456 __typeof__(*(ptr)) __user *__pu_addr = (ptr); \
457 __typeof__(*(ptr)) __pu_val = (x); \
458 int __pu_err = -EFAULT; \
459 \
460 might_fault(); \
461 if (likely(access_ok(VERIFY_WRITE, __pu_addr, size))) { \
462 if (eva_kernel_access()) \
463 __put_kernel_common(__pu_addr, size); \
464 else \
465 __put_user_common(__pu_addr, size); \
466 } \
467 \
468 __pu_err; \
469 })
470
471 #define __put_data_asm(insn, ptr) \
472 { \
473 __asm__ __volatile__( \
474 "1: "insn("%z2", "%3")" # __put_data_asm \n" \
475 "2: \n" \
476 " .insn \n" \
477 " .section .fixup,\"ax\" \n" \
478 "3: li %0, %4 \n" \
479 " j 2b \n" \
480 " .previous \n" \
481 " .section __ex_table,\"a\" \n" \
482 " " __UA_ADDR " 1b, 3b \n" \
483 " .previous \n" \
484 : "=r" (__pu_err) \
485 : "0" (0), "Jr" (__pu_val), "o" (__m(ptr)), \
486 "i" (-EFAULT)); \
487 }
488
489 #define __put_data_asm_ll32(insn, ptr) \
490 { \
491 __asm__ __volatile__( \
492 "1: "insn("%2", "(%3)")" # __put_data_asm_ll32 \n" \
493 "2: "insn("%D2", "4(%3)")" \n" \
494 "3: \n" \
495 " .insn \n" \
496 " .section .fixup,\"ax\" \n" \
497 "4: li %0, %4 \n" \
498 " j 3b \n" \
499 " .previous \n" \
500 " .section __ex_table,\"a\" \n" \
501 " " __UA_ADDR " 1b, 4b \n" \
502 " " __UA_ADDR " 2b, 4b \n" \
503 " .previous" \
504 : "=r" (__pu_err) \
505 : "0" (0), "r" (__pu_val), "r" (ptr), \
506 "i" (-EFAULT)); \
507 }
508
509 extern void __put_user_unknown(void);
510
511 /*
512 * ul{b,h,w} are macros and there are no equivalent macros for EVA.
513 * EVA unaligned access is handled in the ADE exception handler.
514 */
515 #ifndef CONFIG_EVA
516 /*
517 * put_user_unaligned: - Write a simple value into user space.
518 * @x: Value to copy to user space.
519 * @ptr: Destination address, in user space.
520 *
521 * Context: User context only. This function may sleep if pagefaults are
522 * enabled.
523 *
524 * This macro copies a single simple value from kernel space to user
525 * space. It supports simple types like char and int, but not larger
526 * data types like structures or arrays.
527 *
528 * @ptr must have pointer-to-simple-variable type, and @x must be assignable
529 * to the result of dereferencing @ptr.
530 *
531 * Returns zero on success, or -EFAULT on error.
532 */
533 #define put_user_unaligned(x,ptr) \
534 __put_user_unaligned_check((x),(ptr),sizeof(*(ptr)))
535
536 /*
537 * get_user_unaligned: - Get a simple variable from user space.
538 * @x: Variable to store result.
539 * @ptr: Source address, in user space.
540 *
541 * Context: User context only. This function may sleep if pagefaults are
542 * enabled.
543 *
544 * This macro copies a single simple variable from user space to kernel
545 * space. It supports simple types like char and int, but not larger
546 * data types like structures or arrays.
547 *
548 * @ptr must have pointer-to-simple-variable type, and the result of
549 * dereferencing @ptr must be assignable to @x without a cast.
550 *
551 * Returns zero on success, or -EFAULT on error.
552 * On error, the variable @x is set to zero.
553 */
554 #define get_user_unaligned(x,ptr) \
555 __get_user_unaligned_check((x),(ptr),sizeof(*(ptr)))
556
557 /*
558 * __put_user_unaligned: - Write a simple value into user space, with less checking.
559 * @x: Value to copy to user space.
560 * @ptr: Destination address, in user space.
561 *
562 * Context: User context only. This function may sleep if pagefaults are
563 * enabled.
564 *
565 * This macro copies a single simple value from kernel space to user
566 * space. It supports simple types like char and int, but not larger
567 * data types like structures or arrays.
568 *
569 * @ptr must have pointer-to-simple-variable type, and @x must be assignable
570 * to the result of dereferencing @ptr.
571 *
572 * Caller must check the pointer with access_ok() before calling this
573 * function.
574 *
575 * Returns zero on success, or -EFAULT on error.
576 */
577 #define __put_user_unaligned(x,ptr) \
578 __put_user_unaligned_nocheck((x),(ptr),sizeof(*(ptr)))
579
580 /*
581 * __get_user_unaligned: - Get a simple variable from user space, with less checking.
582 * @x: Variable to store result.
583 * @ptr: Source address, in user space.
584 *
585 * Context: User context only. This function may sleep if pagefaults are
586 * enabled.
587 *
588 * This macro copies a single simple variable from user space to kernel
589 * space. It supports simple types like char and int, but not larger
590 * data types like structures or arrays.
591 *
592 * @ptr must have pointer-to-simple-variable type, and the result of
593 * dereferencing @ptr must be assignable to @x without a cast.
594 *
595 * Caller must check the pointer with access_ok() before calling this
596 * function.
597 *
598 * Returns zero on success, or -EFAULT on error.
599 * On error, the variable @x is set to zero.
600 */
601 #define __get_user_unaligned(x,ptr) \
602 __get_user_unaligned_nocheck((x),(ptr),sizeof(*(ptr)))
603
604 /*
605 * Yuck. We need two variants, one for 64bit operation and one
606 * for 32 bit mode and old iron.
607 */
608 #ifdef CONFIG_32BIT
609 #define __GET_USER_UNALIGNED_DW(val, ptr) \
610 __get_user_unaligned_asm_ll32(val, ptr)
611 #endif
612 #ifdef CONFIG_64BIT
613 #define __GET_USER_UNALIGNED_DW(val, ptr) \
614 __get_user_unaligned_asm(val, "uld", ptr)
615 #endif
616
617 extern void __get_user_unaligned_unknown(void);
618
619 #define __get_user_unaligned_common(val, size, ptr) \
620 do { \
621 switch (size) { \
622 case 1: __get_data_asm(val, "lb", ptr); break; \
623 case 2: __get_data_unaligned_asm(val, "ulh", ptr); break; \
624 case 4: __get_data_unaligned_asm(val, "ulw", ptr); break; \
625 case 8: __GET_USER_UNALIGNED_DW(val, ptr); break; \
626 default: __get_user_unaligned_unknown(); break; \
627 } \
628 } while (0)
629
630 #define __get_user_unaligned_nocheck(x,ptr,size) \
631 ({ \
632 int __gu_err; \
633 \
634 __get_user_unaligned_common((x), size, ptr); \
635 __gu_err; \
636 })
637
638 #define __get_user_unaligned_check(x,ptr,size) \
639 ({ \
640 int __gu_err = -EFAULT; \
641 const __typeof__(*(ptr)) __user * __gu_ptr = (ptr); \
642 \
643 if (likely(access_ok(VERIFY_READ, __gu_ptr, size))) \
644 __get_user_unaligned_common((x), size, __gu_ptr); \
645 \
646 __gu_err; \
647 })
648
649 #define __get_data_unaligned_asm(val, insn, addr) \
650 { \
651 long __gu_tmp; \
652 \
653 __asm__ __volatile__( \
654 "1: " insn " %1, %3 \n" \
655 "2: \n" \
656 " .insn \n" \
657 " .section .fixup,\"ax\" \n" \
658 "3: li %0, %4 \n" \
659 " move %1, $0 \n" \
660 " j 2b \n" \
661 " .previous \n" \
662 " .section __ex_table,\"a\" \n" \
663 " "__UA_ADDR "\t1b, 3b \n" \
664 " "__UA_ADDR "\t1b + 4, 3b \n" \
665 " .previous \n" \
666 : "=r" (__gu_err), "=r" (__gu_tmp) \
667 : "0" (0), "o" (__m(addr)), "i" (-EFAULT)); \
668 \
669 (val) = (__typeof__(*(addr))) __gu_tmp; \
670 }
671
672 /*
673 * Get a long long 64 using 32 bit registers.
674 */
675 #define __get_user_unaligned_asm_ll32(val, addr) \
676 { \
677 unsigned long long __gu_tmp; \
678 \
679 __asm__ __volatile__( \
680 "1: ulw %1, (%3) \n" \
681 "2: ulw %D1, 4(%3) \n" \
682 " move %0, $0 \n" \
683 "3: \n" \
684 " .insn \n" \
685 " .section .fixup,\"ax\" \n" \
686 "4: li %0, %4 \n" \
687 " move %1, $0 \n" \
688 " move %D1, $0 \n" \
689 " j 3b \n" \
690 " .previous \n" \
691 " .section __ex_table,\"a\" \n" \
692 " " __UA_ADDR " 1b, 4b \n" \
693 " " __UA_ADDR " 1b + 4, 4b \n" \
694 " " __UA_ADDR " 2b, 4b \n" \
695 " " __UA_ADDR " 2b + 4, 4b \n" \
696 " .previous \n" \
697 : "=r" (__gu_err), "=&r" (__gu_tmp) \
698 : "0" (0), "r" (addr), "i" (-EFAULT)); \
699 (val) = (__typeof__(*(addr))) __gu_tmp; \
700 }
701
702 /*
703 * Yuck. We need two variants, one for 64bit operation and one
704 * for 32 bit mode and old iron.
705 */
706 #ifdef CONFIG_32BIT
707 #define __PUT_USER_UNALIGNED_DW(ptr) __put_user_unaligned_asm_ll32(ptr)
708 #endif
709 #ifdef CONFIG_64BIT
710 #define __PUT_USER_UNALIGNED_DW(ptr) __put_user_unaligned_asm("usd", ptr)
711 #endif
712
713 #define __put_user_unaligned_common(ptr, size) \
714 do { \
715 switch (size) { \
716 case 1: __put_data_asm("sb", ptr); break; \
717 case 2: __put_user_unaligned_asm("ush", ptr); break; \
718 case 4: __put_user_unaligned_asm("usw", ptr); break; \
719 case 8: __PUT_USER_UNALIGNED_DW(ptr); break; \
720 default: __put_user_unaligned_unknown(); break; \
721 } while (0)
722
723 #define __put_user_unaligned_nocheck(x,ptr,size) \
724 ({ \
725 __typeof__(*(ptr)) __pu_val; \
726 int __pu_err = 0; \
727 \
728 __pu_val = (x); \
729 __put_user_unaligned_common(ptr, size); \
730 __pu_err; \
731 })
732
733 #define __put_user_unaligned_check(x,ptr,size) \
734 ({ \
735 __typeof__(*(ptr)) __user *__pu_addr = (ptr); \
736 __typeof__(*(ptr)) __pu_val = (x); \
737 int __pu_err = -EFAULT; \
738 \
739 if (likely(access_ok(VERIFY_WRITE, __pu_addr, size))) \
740 __put_user_unaligned_common(__pu_addr, size); \
741 \
742 __pu_err; \
743 })
744
745 #define __put_user_unaligned_asm(insn, ptr) \
746 { \
747 __asm__ __volatile__( \
748 "1: " insn " %z2, %3 # __put_user_unaligned_asm\n" \
749 "2: \n" \
750 " .insn \n" \
751 " .section .fixup,\"ax\" \n" \
752 "3: li %0, %4 \n" \
753 " j 2b \n" \
754 " .previous \n" \
755 " .section __ex_table,\"a\" \n" \
756 " " __UA_ADDR " 1b, 3b \n" \
757 " .previous \n" \
758 : "=r" (__pu_err) \
759 : "0" (0), "Jr" (__pu_val), "o" (__m(ptr)), \
760 "i" (-EFAULT)); \
761 }
762
763 #define __put_user_unaligned_asm_ll32(ptr) \
764 { \
765 __asm__ __volatile__( \
766 "1: sw %2, (%3) # __put_user_unaligned_asm_ll32 \n" \
767 "2: sw %D2, 4(%3) \n" \
768 "3: \n" \
769 " .insn \n" \
770 " .section .fixup,\"ax\" \n" \
771 "4: li %0, %4 \n" \
772 " j 3b \n" \
773 " .previous \n" \
774 " .section __ex_table,\"a\" \n" \
775 " " __UA_ADDR " 1b, 4b \n" \
776 " " __UA_ADDR " 1b + 4, 4b \n" \
777 " " __UA_ADDR " 2b, 4b \n" \
778 " " __UA_ADDR " 2b + 4, 4b \n" \
779 " .previous" \
780 : "=r" (__pu_err) \
781 : "0" (0), "r" (__pu_val), "r" (ptr), \
782 "i" (-EFAULT)); \
783 }
784
785 extern void __put_user_unaligned_unknown(void);
786 #endif
787
788 /*
789 * We're generating jump to subroutines which will be outside the range of
790 * jump instructions
791 */
792 #ifdef MODULE
793 #define __MODULE_JAL(destination) \
794 ".set\tnoat\n\t" \
795 __UA_LA "\t$1, " #destination "\n\t" \
796 "jalr\t$1\n\t" \
797 ".set\tat\n\t"
798 #else
799 #define __MODULE_JAL(destination) \
800 "jal\t" #destination "\n\t"
801 #endif
802
803 #if defined(CONFIG_CPU_DADDI_WORKAROUNDS) || (defined(CONFIG_EVA) && \
804 defined(CONFIG_CPU_HAS_PREFETCH))
805 #define DADDI_SCRATCH "$3"
806 #else
807 #define DADDI_SCRATCH "$0"
808 #endif
809
810 extern size_t __copy_user(void *__to, const void *__from, size_t __n);
811
812 #ifndef CONFIG_EVA
813 #define __invoke_copy_to_user(to, from, n) \
814 ({ \
815 register void __user *__cu_to_r __asm__("$4"); \
816 register const void *__cu_from_r __asm__("$5"); \
817 register long __cu_len_r __asm__("$6"); \
818 \
819 __cu_to_r = (to); \
820 __cu_from_r = (from); \
821 __cu_len_r = (n); \
822 __asm__ __volatile__( \
823 __MODULE_JAL(__copy_user) \
824 : "+r" (__cu_to_r), "+r" (__cu_from_r), "+r" (__cu_len_r) \
825 : \
826 : "$8", "$9", "$10", "$11", "$12", "$14", "$15", "$24", "$31", \
827 DADDI_SCRATCH, "memory"); \
828 __cu_len_r; \
829 })
830
831 #define __invoke_copy_to_kernel(to, from, n) \
832 __invoke_copy_to_user(to, from, n)
833
834 #endif
835
836 /*
837 * __copy_to_user: - Copy a block of data into user space, with less checking.
838 * @to: Destination address, in user space.
839 * @from: Source address, in kernel space.
840 * @n: Number of bytes to copy.
841 *
842 * Context: User context only. This function may sleep if pagefaults are
843 * enabled.
844 *
845 * Copy data from kernel space to user space. Caller must check
846 * the specified block with access_ok() before calling this function.
847 *
848 * Returns number of bytes that could not be copied.
849 * On success, this will be zero.
850 */
851 #define __copy_to_user(to, from, n) \
852 ({ \
853 void __user *__cu_to; \
854 const void *__cu_from; \
855 long __cu_len; \
856 \
857 __cu_to = (to); \
858 __cu_from = (from); \
859 __cu_len = (n); \
860 might_fault(); \
861 if (eva_kernel_access()) \
862 __cu_len = __invoke_copy_to_kernel(__cu_to, __cu_from, \
863 __cu_len); \
864 else \
865 __cu_len = __invoke_copy_to_user(__cu_to, __cu_from, \
866 __cu_len); \
867 __cu_len; \
868 })
869
870 extern size_t __copy_user_inatomic(void *__to, const void *__from, size_t __n);
871
872 #define __copy_to_user_inatomic(to, from, n) \
873 ({ \
874 void __user *__cu_to; \
875 const void *__cu_from; \
876 long __cu_len; \
877 \
878 __cu_to = (to); \
879 __cu_from = (from); \
880 __cu_len = (n); \
881 if (eva_kernel_access()) \
882 __cu_len = __invoke_copy_to_kernel(__cu_to, __cu_from, \
883 __cu_len); \
884 else \
885 __cu_len = __invoke_copy_to_user(__cu_to, __cu_from, \
886 __cu_len); \
887 __cu_len; \
888 })
889
890 #define __copy_from_user_inatomic(to, from, n) \
891 ({ \
892 void *__cu_to; \
893 const void __user *__cu_from; \
894 long __cu_len; \
895 \
896 __cu_to = (to); \
897 __cu_from = (from); \
898 __cu_len = (n); \
899 if (eva_kernel_access()) \
900 __cu_len = __invoke_copy_from_kernel_inatomic(__cu_to, \
901 __cu_from,\
902 __cu_len);\
903 else \
904 __cu_len = __invoke_copy_from_user_inatomic(__cu_to, \
905 __cu_from, \
906 __cu_len); \
907 __cu_len; \
908 })
909
910 /*
911 * copy_to_user: - Copy a block of data into user space.
912 * @to: Destination address, in user space.
913 * @from: Source address, in kernel space.
914 * @n: Number of bytes to copy.
915 *
916 * Context: User context only. This function may sleep if pagefaults are
917 * enabled.
918 *
919 * Copy data from kernel space to user space.
920 *
921 * Returns number of bytes that could not be copied.
922 * On success, this will be zero.
923 */
924 #define copy_to_user(to, from, n) \
925 ({ \
926 void __user *__cu_to; \
927 const void *__cu_from; \
928 long __cu_len; \
929 \
930 __cu_to = (to); \
931 __cu_from = (from); \
932 __cu_len = (n); \
933 if (eva_kernel_access()) { \
934 __cu_len = __invoke_copy_to_kernel(__cu_to, \
935 __cu_from, \
936 __cu_len); \
937 } else { \
938 if (access_ok(VERIFY_WRITE, __cu_to, __cu_len)) { \
939 might_fault(); \
940 __cu_len = __invoke_copy_to_user(__cu_to, \
941 __cu_from, \
942 __cu_len); \
943 } \
944 } \
945 __cu_len; \
946 })
947
948 #ifndef CONFIG_EVA
949
950 #define __invoke_copy_from_user(to, from, n) \
951 ({ \
952 register void *__cu_to_r __asm__("$4"); \
953 register const void __user *__cu_from_r __asm__("$5"); \
954 register long __cu_len_r __asm__("$6"); \
955 \
956 __cu_to_r = (to); \
957 __cu_from_r = (from); \
958 __cu_len_r = (n); \
959 __asm__ __volatile__( \
960 ".set\tnoreorder\n\t" \
961 __MODULE_JAL(__copy_user) \
962 ".set\tnoat\n\t" \
963 __UA_ADDU "\t$1, %1, %2\n\t" \
964 ".set\tat\n\t" \
965 ".set\treorder" \
966 : "+r" (__cu_to_r), "+r" (__cu_from_r), "+r" (__cu_len_r) \
967 : \
968 : "$8", "$9", "$10", "$11", "$12", "$14", "$15", "$24", "$31", \
969 DADDI_SCRATCH, "memory"); \
970 __cu_len_r; \
971 })
972
973 #define __invoke_copy_from_kernel(to, from, n) \
974 __invoke_copy_from_user(to, from, n)
975
976 /* For userland <-> userland operations */
977 #define ___invoke_copy_in_user(to, from, n) \
978 __invoke_copy_from_user(to, from, n)
979
980 /* For kernel <-> kernel operations */
981 #define ___invoke_copy_in_kernel(to, from, n) \
982 __invoke_copy_from_user(to, from, n)
983
984 #define __invoke_copy_from_user_inatomic(to, from, n) \
985 ({ \
986 register void *__cu_to_r __asm__("$4"); \
987 register const void __user *__cu_from_r __asm__("$5"); \
988 register long __cu_len_r __asm__("$6"); \
989 \
990 __cu_to_r = (to); \
991 __cu_from_r = (from); \
992 __cu_len_r = (n); \
993 __asm__ __volatile__( \
994 ".set\tnoreorder\n\t" \
995 __MODULE_JAL(__copy_user_inatomic) \
996 ".set\tnoat\n\t" \
997 __UA_ADDU "\t$1, %1, %2\n\t" \
998 ".set\tat\n\t" \
999 ".set\treorder" \
1000 : "+r" (__cu_to_r), "+r" (__cu_from_r), "+r" (__cu_len_r) \
1001 : \
1002 : "$8", "$9", "$10", "$11", "$12", "$14", "$15", "$24", "$31", \
1003 DADDI_SCRATCH, "memory"); \
1004 __cu_len_r; \
1005 })
1006
1007 #define __invoke_copy_from_kernel_inatomic(to, from, n) \
1008 __invoke_copy_from_user_inatomic(to, from, n) \
1009
1010 #else
1011
1012 /* EVA specific functions */
1013
1014 extern size_t __copy_user_inatomic_eva(void *__to, const void *__from,
1015 size_t __n);
1016 extern size_t __copy_from_user_eva(void *__to, const void *__from,
1017 size_t __n);
1018 extern size_t __copy_to_user_eva(void *__to, const void *__from,
1019 size_t __n);
1020 extern size_t __copy_in_user_eva(void *__to, const void *__from, size_t __n);
1021
1022 #define __invoke_copy_from_user_eva_generic(to, from, n, func_ptr) \
1023 ({ \
1024 register void *__cu_to_r __asm__("$4"); \
1025 register const void __user *__cu_from_r __asm__("$5"); \
1026 register long __cu_len_r __asm__("$6"); \
1027 \
1028 __cu_to_r = (to); \
1029 __cu_from_r = (from); \
1030 __cu_len_r = (n); \
1031 __asm__ __volatile__( \
1032 ".set\tnoreorder\n\t" \
1033 __MODULE_JAL(func_ptr) \
1034 ".set\tnoat\n\t" \
1035 __UA_ADDU "\t$1, %1, %2\n\t" \
1036 ".set\tat\n\t" \
1037 ".set\treorder" \
1038 : "+r" (__cu_to_r), "+r" (__cu_from_r), "+r" (__cu_len_r) \
1039 : \
1040 : "$8", "$9", "$10", "$11", "$12", "$14", "$15", "$24", "$31", \
1041 DADDI_SCRATCH, "memory"); \
1042 __cu_len_r; \
1043 })
1044
1045 #define __invoke_copy_to_user_eva_generic(to, from, n, func_ptr) \
1046 ({ \
1047 register void *__cu_to_r __asm__("$4"); \
1048 register const void __user *__cu_from_r __asm__("$5"); \
1049 register long __cu_len_r __asm__("$6"); \
1050 \
1051 __cu_to_r = (to); \
1052 __cu_from_r = (from); \
1053 __cu_len_r = (n); \
1054 __asm__ __volatile__( \
1055 __MODULE_JAL(func_ptr) \
1056 : "+r" (__cu_to_r), "+r" (__cu_from_r), "+r" (__cu_len_r) \
1057 : \
1058 : "$8", "$9", "$10", "$11", "$12", "$14", "$15", "$24", "$31", \
1059 DADDI_SCRATCH, "memory"); \
1060 __cu_len_r; \
1061 })
1062
1063 /*
1064 * Source or destination address is in userland. We need to go through
1065 * the TLB
1066 */
1067 #define __invoke_copy_from_user(to, from, n) \
1068 __invoke_copy_from_user_eva_generic(to, from, n, __copy_from_user_eva)
1069
1070 #define __invoke_copy_from_user_inatomic(to, from, n) \
1071 __invoke_copy_from_user_eva_generic(to, from, n, \
1072 __copy_user_inatomic_eva)
1073
1074 #define __invoke_copy_to_user(to, from, n) \
1075 __invoke_copy_to_user_eva_generic(to, from, n, __copy_to_user_eva)
1076
1077 #define ___invoke_copy_in_user(to, from, n) \
1078 __invoke_copy_from_user_eva_generic(to, from, n, __copy_in_user_eva)
1079
1080 /*
1081 * Source or destination address in the kernel. We are not going through
1082 * the TLB
1083 */
1084 #define __invoke_copy_from_kernel(to, from, n) \
1085 __invoke_copy_from_user_eva_generic(to, from, n, __copy_user)
1086
1087 #define __invoke_copy_from_kernel_inatomic(to, from, n) \
1088 __invoke_copy_from_user_eva_generic(to, from, n, __copy_user_inatomic)
1089
1090 #define __invoke_copy_to_kernel(to, from, n) \
1091 __invoke_copy_to_user_eva_generic(to, from, n, __copy_user)
1092
1093 #define ___invoke_copy_in_kernel(to, from, n) \
1094 __invoke_copy_from_user_eva_generic(to, from, n, __copy_user)
1095
1096 #endif /* CONFIG_EVA */
1097
1098 /*
1099 * __copy_from_user: - Copy a block of data from user space, with less checking.
1100 * @to: Destination address, in kernel space.
1101 * @from: Source address, in user space.
1102 * @n: Number of bytes to copy.
1103 *
1104 * Context: User context only. This function may sleep if pagefaults are
1105 * enabled.
1106 *
1107 * Copy data from user space to kernel space. Caller must check
1108 * the specified block with access_ok() before calling this function.
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 (eva_kernel_access()) { \
1126 __cu_len = __invoke_copy_from_kernel(__cu_to, \
1127 __cu_from, \
1128 __cu_len); \
1129 } else { \
1130 might_fault(); \
1131 __cu_len = __invoke_copy_from_user(__cu_to, __cu_from, \
1132 __cu_len); \
1133 } \
1134 __cu_len; \
1135 })
1136
1137 /*
1138 * copy_from_user: - Copy a block of data from user space.
1139 * @to: Destination address, in kernel space.
1140 * @from: Source address, in user space.
1141 * @n: Number of bytes to copy.
1142 *
1143 * Context: User context only. This function may sleep if pagefaults are
1144 * enabled.
1145 *
1146 * Copy data from user space to kernel space.
1147 *
1148 * Returns number of bytes that could not be copied.
1149 * On success, this will be zero.
1150 *
1151 * If some data could not be copied, this function will pad the copied
1152 * data to the requested size using zero bytes.
1153 */
1154 #define copy_from_user(to, from, n) \
1155 ({ \
1156 void *__cu_to; \
1157 const void __user *__cu_from; \
1158 long __cu_len; \
1159 \
1160 __cu_to = (to); \
1161 __cu_from = (from); \
1162 __cu_len = (n); \
1163 if (eva_kernel_access()) { \
1164 __cu_len = __invoke_copy_from_kernel(__cu_to, \
1165 __cu_from, \
1166 __cu_len); \
1167 } else { \
1168 if (access_ok(VERIFY_READ, __cu_from, __cu_len)) { \
1169 might_fault(); \
1170 __cu_len = __invoke_copy_from_user(__cu_to, \
1171 __cu_from, \
1172 __cu_len); \
1173 } \
1174 } \
1175 __cu_len; \
1176 })
1177
1178 #define __copy_in_user(to, from, n) \
1179 ({ \
1180 void __user *__cu_to; \
1181 const void __user *__cu_from; \
1182 long __cu_len; \
1183 \
1184 __cu_to = (to); \
1185 __cu_from = (from); \
1186 __cu_len = (n); \
1187 if (eva_kernel_access()) { \
1188 __cu_len = ___invoke_copy_in_kernel(__cu_to, __cu_from, \
1189 __cu_len); \
1190 } else { \
1191 might_fault(); \
1192 __cu_len = ___invoke_copy_in_user(__cu_to, __cu_from, \
1193 __cu_len); \
1194 } \
1195 __cu_len; \
1196 })
1197
1198 #define copy_in_user(to, from, n) \
1199 ({ \
1200 void __user *__cu_to; \
1201 const void __user *__cu_from; \
1202 long __cu_len; \
1203 \
1204 __cu_to = (to); \
1205 __cu_from = (from); \
1206 __cu_len = (n); \
1207 if (eva_kernel_access()) { \
1208 __cu_len = ___invoke_copy_in_kernel(__cu_to,__cu_from, \
1209 __cu_len); \
1210 } else { \
1211 if (likely(access_ok(VERIFY_READ, __cu_from, __cu_len) &&\
1212 access_ok(VERIFY_WRITE, __cu_to, __cu_len))) {\
1213 might_fault(); \
1214 __cu_len = ___invoke_copy_in_user(__cu_to, \
1215 __cu_from, \
1216 __cu_len); \
1217 } \
1218 } \
1219 __cu_len; \
1220 })
1221
1222 /*
1223 * __clear_user: - Zero a block of memory in user space, with less checking.
1224 * @to: Destination address, in user space.
1225 * @n: Number of bytes to zero.
1226 *
1227 * Zero a block of memory in user space. Caller must check
1228 * the specified block with access_ok() before calling this function.
1229 *
1230 * Returns number of bytes that could not be cleared.
1231 * On success, this will be zero.
1232 */
1233 static inline __kernel_size_t
1234 __clear_user(void __user *addr, __kernel_size_t size)
1235 {
1236 __kernel_size_t res;
1237
1238 if (eva_kernel_access()) {
1239 __asm__ __volatile__(
1240 "move\t$4, %1\n\t"
1241 "move\t$5, $0\n\t"
1242 "move\t$6, %2\n\t"
1243 __MODULE_JAL(__bzero_kernel)
1244 "move\t%0, $6"
1245 : "=r" (res)
1246 : "r" (addr), "r" (size)
1247 : "$4", "$5", "$6", __UA_t0, __UA_t1, "$31");
1248 } else {
1249 might_fault();
1250 __asm__ __volatile__(
1251 "move\t$4, %1\n\t"
1252 "move\t$5, $0\n\t"
1253 "move\t$6, %2\n\t"
1254 __MODULE_JAL(__bzero)
1255 "move\t%0, $6"
1256 : "=r" (res)
1257 : "r" (addr), "r" (size)
1258 : "$4", "$5", "$6", __UA_t0, __UA_t1, "$31");
1259 }
1260
1261 return res;
1262 }
1263
1264 #define clear_user(addr,n) \
1265 ({ \
1266 void __user * __cl_addr = (addr); \
1267 unsigned long __cl_size = (n); \
1268 if (__cl_size && access_ok(VERIFY_WRITE, \
1269 __cl_addr, __cl_size)) \
1270 __cl_size = __clear_user(__cl_addr, __cl_size); \
1271 __cl_size; \
1272 })
1273
1274 /*
1275 * __strncpy_from_user: - Copy a NUL terminated string from userspace, with less checking.
1276 * @dst: Destination address, in kernel space. This buffer must be at
1277 * least @count bytes long.
1278 * @src: Source address, in user space.
1279 * @count: Maximum number of bytes to copy, including the trailing NUL.
1280 *
1281 * Copies a NUL-terminated string from userspace to kernel space.
1282 * Caller must check the specified block with access_ok() before calling
1283 * this function.
1284 *
1285 * On success, returns the length of the string (not including the trailing
1286 * NUL).
1287 *
1288 * If access to userspace fails, returns -EFAULT (some data may have been
1289 * copied).
1290 *
1291 * If @count is smaller than the length of the string, copies @count bytes
1292 * and returns @count.
1293 */
1294 static inline long
1295 __strncpy_from_user(char *__to, const char __user *__from, long __len)
1296 {
1297 long res;
1298
1299 if (eva_kernel_access()) {
1300 __asm__ __volatile__(
1301 "move\t$4, %1\n\t"
1302 "move\t$5, %2\n\t"
1303 "move\t$6, %3\n\t"
1304 __MODULE_JAL(__strncpy_from_kernel_nocheck_asm)
1305 "move\t%0, $2"
1306 : "=r" (res)
1307 : "r" (__to), "r" (__from), "r" (__len)
1308 : "$2", "$3", "$4", "$5", "$6", __UA_t0, "$31", "memory");
1309 } else {
1310 might_fault();
1311 __asm__ __volatile__(
1312 "move\t$4, %1\n\t"
1313 "move\t$5, %2\n\t"
1314 "move\t$6, %3\n\t"
1315 __MODULE_JAL(__strncpy_from_user_nocheck_asm)
1316 "move\t%0, $2"
1317 : "=r" (res)
1318 : "r" (__to), "r" (__from), "r" (__len)
1319 : "$2", "$3", "$4", "$5", "$6", __UA_t0, "$31", "memory");
1320 }
1321
1322 return res;
1323 }
1324
1325 /*
1326 * strncpy_from_user: - Copy a NUL terminated string from userspace.
1327 * @dst: Destination address, in kernel space. This buffer must be at
1328 * least @count bytes long.
1329 * @src: Source address, in user space.
1330 * @count: Maximum number of bytes to copy, including the trailing NUL.
1331 *
1332 * Copies a NUL-terminated string from userspace to kernel space.
1333 *
1334 * On success, returns the length of the string (not including the trailing
1335 * NUL).
1336 *
1337 * If access to userspace fails, returns -EFAULT (some data may have been
1338 * copied).
1339 *
1340 * If @count is smaller than the length of the string, copies @count bytes
1341 * and returns @count.
1342 */
1343 static inline long
1344 strncpy_from_user(char *__to, const char __user *__from, long __len)
1345 {
1346 long res;
1347
1348 if (eva_kernel_access()) {
1349 __asm__ __volatile__(
1350 "move\t$4, %1\n\t"
1351 "move\t$5, %2\n\t"
1352 "move\t$6, %3\n\t"
1353 __MODULE_JAL(__strncpy_from_kernel_asm)
1354 "move\t%0, $2"
1355 : "=r" (res)
1356 : "r" (__to), "r" (__from), "r" (__len)
1357 : "$2", "$3", "$4", "$5", "$6", __UA_t0, "$31", "memory");
1358 } else {
1359 might_fault();
1360 __asm__ __volatile__(
1361 "move\t$4, %1\n\t"
1362 "move\t$5, %2\n\t"
1363 "move\t$6, %3\n\t"
1364 __MODULE_JAL(__strncpy_from_user_asm)
1365 "move\t%0, $2"
1366 : "=r" (res)
1367 : "r" (__to), "r" (__from), "r" (__len)
1368 : "$2", "$3", "$4", "$5", "$6", __UA_t0, "$31", "memory");
1369 }
1370
1371 return res;
1372 }
1373
1374 /*
1375 * strlen_user: - Get the size of a string in user space.
1376 * @str: The string to measure.
1377 *
1378 * Context: User context only. This function may sleep if pagefaults are
1379 * enabled.
1380 *
1381 * Get the size of a NUL-terminated string in user space.
1382 *
1383 * Returns the size of the string INCLUDING the terminating NUL.
1384 * On exception, returns 0.
1385 *
1386 * If there is a limit on the length of a valid string, you may wish to
1387 * consider using strnlen_user() instead.
1388 */
1389 static inline long strlen_user(const char __user *s)
1390 {
1391 long res;
1392
1393 if (eva_kernel_access()) {
1394 __asm__ __volatile__(
1395 "move\t$4, %1\n\t"
1396 __MODULE_JAL(__strlen_kernel_asm)
1397 "move\t%0, $2"
1398 : "=r" (res)
1399 : "r" (s)
1400 : "$2", "$4", __UA_t0, "$31");
1401 } else {
1402 might_fault();
1403 __asm__ __volatile__(
1404 "move\t$4, %1\n\t"
1405 __MODULE_JAL(__strlen_user_asm)
1406 "move\t%0, $2"
1407 : "=r" (res)
1408 : "r" (s)
1409 : "$2", "$4", __UA_t0, "$31");
1410 }
1411
1412 return res;
1413 }
1414
1415 /* Returns: 0 if bad, string length+1 (memory size) of string if ok */
1416 static inline long __strnlen_user(const char __user *s, long n)
1417 {
1418 long res;
1419
1420 if (eva_kernel_access()) {
1421 __asm__ __volatile__(
1422 "move\t$4, %1\n\t"
1423 "move\t$5, %2\n\t"
1424 __MODULE_JAL(__strnlen_kernel_nocheck_asm)
1425 "move\t%0, $2"
1426 : "=r" (res)
1427 : "r" (s), "r" (n)
1428 : "$2", "$4", "$5", __UA_t0, "$31");
1429 } else {
1430 might_fault();
1431 __asm__ __volatile__(
1432 "move\t$4, %1\n\t"
1433 "move\t$5, %2\n\t"
1434 __MODULE_JAL(__strnlen_user_nocheck_asm)
1435 "move\t%0, $2"
1436 : "=r" (res)
1437 : "r" (s), "r" (n)
1438 : "$2", "$4", "$5", __UA_t0, "$31");
1439 }
1440
1441 return res;
1442 }
1443
1444 /*
1445 * strnlen_user: - Get the size of a string in user space.
1446 * @str: The string to measure.
1447 *
1448 * Context: User context only. This function may sleep if pagefaults are
1449 * enabled.
1450 *
1451 * Get the size of a NUL-terminated string in user space.
1452 *
1453 * Returns the size of the string INCLUDING the terminating NUL.
1454 * On exception, returns 0.
1455 * If the string is too long, returns a value greater than @n.
1456 */
1457 static inline long strnlen_user(const char __user *s, long n)
1458 {
1459 long res;
1460
1461 might_fault();
1462 if (eva_kernel_access()) {
1463 __asm__ __volatile__(
1464 "move\t$4, %1\n\t"
1465 "move\t$5, %2\n\t"
1466 __MODULE_JAL(__strnlen_kernel_asm)
1467 "move\t%0, $2"
1468 : "=r" (res)
1469 : "r" (s), "r" (n)
1470 : "$2", "$4", "$5", __UA_t0, "$31");
1471 } else {
1472 __asm__ __volatile__(
1473 "move\t$4, %1\n\t"
1474 "move\t$5, %2\n\t"
1475 __MODULE_JAL(__strnlen_user_asm)
1476 "move\t%0, $2"
1477 : "=r" (res)
1478 : "r" (s), "r" (n)
1479 : "$2", "$4", "$5", __UA_t0, "$31");
1480 }
1481
1482 return res;
1483 }
1484
1485 struct exception_table_entry
1486 {
1487 unsigned long insn;
1488 unsigned long nextinsn;
1489 };
1490
1491 extern int fixup_exception(struct pt_regs *regs);
1492
1493 #endif /* _ASM_UACCESS_H */
Linux kernel - Deliverables
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