summaryrefslogtreecommitdiffstats
path: root/arch/arc/include/asm/uaccess.h
blob: 41faf17cd28d2ced7461f4e6860d2456fb49f8ae (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
/*
 * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * vineetg: June 2010
 *    -__clear_user( ) called multiple times during elf load was byte loop
 *    converted to do as much word clear as possible.
 *
 * vineetg: Dec 2009
 *    -Hand crafted constant propagation for "constant" copy sizes
 *    -stock kernel shrunk by 33K at -O3
 *
 * vineetg: Sept 2009
 *    -Added option to (UN)inline copy_(to|from)_user to reduce code sz
 *    -kernel shrunk by 200K even at -O3 (gcc 4.2.1)
 *    -Enabled when doing -Os
 *
 * Amit Bhor, Sameer Dhavale: Codito Technologies 2004
 */

#ifndef _ASM_ARC_UACCESS_H
#define _ASM_ARC_UACCESS_H

#include <linux/sched.h>
#include <asm/errno.h>
#include <linux/string.h>	/* for generic string functions */


#define __kernel_ok		(segment_eq(get_fs(), KERNEL_DS))

/*
 * Algorithmically, for __user_ok() we want do:
 * 	(start < TASK_SIZE) && (start+len < TASK_SIZE)
 * where TASK_SIZE could either be retrieved from thread_info->addr_limit or
 * emitted directly in code.
 *
 * This can however be rewritten as follows:
 *	(len <= TASK_SIZE) && (start+len < TASK_SIZE)
 *
 * Because it essentially checks if buffer end is within limit and @len is
 * non-ngeative, which implies that buffer start will be within limit too.
 *
 * The reason for rewriting being, for majority of cases, @len is generally
 * compile time constant, causing first sub-expression to be compile time
 * subsumed.
 *
 * The second part would generate weird large LIMMs e.g. (0x6000_0000 - 0x10),
 * so we check for TASK_SIZE using get_fs() since the addr_limit load from mem
 * would already have been done at this call site for __kernel_ok()
 *
 */
#define __user_ok(addr, sz)	(((sz) <= TASK_SIZE) && \
				 ((addr) <= (get_fs() - (sz))))
#define __access_ok(addr, sz)	(unlikely(__kernel_ok) || \
				 likely(__user_ok((addr), (sz))))

/*********** Single byte/hword/word copies ******************/

#define __get_user_fn(sz, u, k)					\
({								\
	long __ret = 0;	/* success by default */	\
	switch (sz) {						\
	case 1: __arc_get_user_one(*(k), u, "ldb", __ret); break;	\
	case 2: __arc_get_user_one(*(k), u, "ldw", __ret); break;	\
	case 4: __arc_get_user_one(*(k), u, "ld", __ret);  break;	\
	case 8: __arc_get_user_one_64(*(k), u, __ret);     break;	\
	}							\
	__ret;							\
})

/*
 * Returns 0 on success, -EFAULT if not.
 * @ret already contains 0 - given that errors will be less likely
 * (hence +r asm constraint below).
 * In case of error, fixup code will make it -EFAULT
 */
#define __arc_get_user_one(dst, src, op, ret)	\
	__asm__ __volatile__(                   \
	"1:	"op"    %1,[%2]\n"		\
	"2:	;nop\n"				\
	"	.section .fixup, \"ax\"\n"	\
	"	.align 4\n"			\
	"3:	# return -EFAULT\n"		\
	"	mov %0, %3\n"			\
	"	# zero out dst ptr\n"		\
	"	mov %1,  0\n"			\
	"	j   2b\n"			\
	"	.previous\n"			\
	"	.section __ex_table, \"a\"\n"	\
	"	.align 4\n"			\
	"	.word 1b,3b\n"			\
	"	.previous\n"			\
						\
	: "+r" (ret), "=r" (dst)		\
	: "r" (src), "ir" (-EFAULT))

#define __arc_get_user_one_64(dst, src, ret)	\
	__asm__ __volatile__(                   \
	"1:	ld   %1,[%2]\n"			\
	"4:	ld  %R1,[%2, 4]\n"		\
	"2:	;nop\n"				\
	"	.section .fixup, \"ax\"\n"	\
	"	.align 4\n"			\
	"3:	# return -EFAULT\n"		\
	"	mov %0, %3\n"			\
	"	# zero out dst ptr\n"		\
	"	mov %1,  0\n"			\
	"	mov %R1, 0\n"			\
	"	j   2b\n"			\
	"	.previous\n"			\
	"	.section __ex_table, \"a\"\n"	\
	"	.align 4\n"			\
	"	.word 1b,3b\n"			\
	"	.word 4b,3b\n"			\
	"	.previous\n"			\
						\
	: "+r" (ret), "=r" (dst)		\
	: "r" (src), "ir" (-EFAULT))

#define __put_user_fn(sz, u, k)					\
({								\
	long __ret = 0;	/* success by default */	\
	switch (sz) {						\
	case 1: __arc_put_user_one(*(k), u, "stb", __ret); break;	\
	case 2: __arc_put_user_one(*(k), u, "stw", __ret); break;	\
	case 4: __arc_put_user_one(*(k), u, "st", __ret);  break;	\
	case 8: __arc_put_user_one_64(*(k), u, __ret);     break;	\
	}							\
	__ret;							\
})

#define __arc_put_user_one(src, dst, op, ret)	\
	__asm__ __volatile__(                   \
	"1:	"op"    %1,[%2]\n"		\
	"2:	;nop\n"				\
	"	.section .fixup, \"ax\"\n"	\
	"	.align 4\n"			\
	"3:	mov %0, %3\n"			\
	"	j   2b\n"			\
	"	.previous\n"			\
	"	.section __ex_table, \"a\"\n"	\
	"	.align 4\n"			\
	"	.word 1b,3b\n"			\
	"	.previous\n"			\
						\
	: "+r" (ret)				\
	: "r" (src), "r" (dst), "ir" (-EFAULT))

#define __arc_put_user_one_64(src, dst, ret)	\
	__asm__ __volatile__(                   \
	"1:	st   %1,[%2]\n"			\
	"4:	st  %R1,[%2, 4]\n"		\
	"2:	;nop\n"				\
	"	.section .fixup, \"ax\"\n"	\
	"	.align 4\n"			\
	"3:	mov %0, %3\n"			\
	"	j   2b\n"			\
	"	.previous\n"			\
	"	.section __ex_table, \"a\"\n"	\
	"	.align 4\n"			\
	"	.word 1b,3b\n"			\
	"	.word 4b,3b\n"			\
	"	.previous\n"			\
						\
	: "+r" (ret)				\
	: "r" (src), "r" (dst), "ir" (-EFAULT))


static inline unsigned long
__arc_copy_from_user(void *to, const void __user *from, unsigned long n)
{
	long res = 0;
	char val;
	unsigned long tmp1, tmp2, tmp3, tmp4;
	unsigned long orig_n = n;

	if (n == 0)
		return 0;

	/* unaligned */
	if (((unsigned long)to & 0x3) || ((unsigned long)from & 0x3)) {

		unsigned char tmp;

		__asm__ __volatile__ (
		"	mov.f   lp_count, %0		\n"
		"	lpnz 2f				\n"
		"1:	ldb.ab  %1, [%3, 1]		\n"
		"	stb.ab  %1, [%2, 1]		\n"
		"	sub     %0,%0,1			\n"
		"2:	;nop				\n"
		"	.section .fixup, \"ax\"		\n"
		"	.align 4			\n"
		"3:	j   2b				\n"
		"	.previous			\n"
		"	.section __ex_table, \"a\"	\n"
		"	.align 4			\n"
		"	.word   1b, 3b			\n"
		"	.previous			\n"

		: "+r" (n),
		/*
		 * Note as an '&' earlyclobber operand to make sure the
		 * temporary register inside the loop is not the same as
		 *  FROM or TO.
		*/
		  "=&r" (tmp), "+r" (to), "+r" (from)
		:
		: "lp_count", "lp_start", "lp_end", "memory");

		return n;
	}

	/*
	 * Hand-crafted constant propagation to reduce code sz of the
	 * laddered copy 16x,8,4,2,1
	 */
	if (__builtin_constant_p(orig_n)) {
		res = orig_n;

		if (orig_n / 16) {
			orig_n = orig_n % 16;

			__asm__ __volatile__(
			"	lsr   lp_count, %7,4		\n"
			"	lp    3f			\n"
			"1:	ld.ab   %3, [%2, 4]		\n"
			"11:	ld.ab   %4, [%2, 4]		\n"
			"12:	ld.ab   %5, [%2, 4]		\n"
			"13:	ld.ab   %6, [%2, 4]		\n"
			"	st.ab   %3, [%1, 4]		\n"
			"	st.ab   %4, [%1, 4]		\n"
			"	st.ab   %5, [%1, 4]		\n"
			"	st.ab   %6, [%1, 4]		\n"
			"	sub     %0,%0,16		\n"
			"3:	;nop				\n"
			"	.section .fixup, \"ax\"		\n"
			"	.align 4			\n"
			"4:	j   3b				\n"
			"	.previous			\n"
			"	.section __ex_table, \"a\"	\n"
			"	.align 4			\n"
			"	.word   1b, 4b			\n"
			"	.word   11b,4b			\n"
			"	.word   12b,4b			\n"
			"	.word   13b,4b			\n"
			"	.previous			\n"
			: "+r" (res), "+r"(to), "+r"(from),
			  "=r"(tmp1), "=r"(tmp2), "=r"(tmp3), "=r"(tmp4)
			: "ir"(n)
			: "lp_count", "memory");
		}
		if (orig_n / 8) {
			orig_n = orig_n % 8;

			__asm__ __volatile__(
			"14:	ld.ab   %3, [%2,4]		\n"
			"15:	ld.ab   %4, [%2,4]		\n"
			"	st.ab   %3, [%1,4]		\n"
			"	st.ab   %4, [%1,4]		\n"
			"	sub     %0,%0,8			\n"
			"31:	;nop				\n"
			"	.section .fixup, \"ax\"		\n"
			"	.align 4			\n"
			"4:	j   31b				\n"
			"	.previous			\n"
			"	.section __ex_table, \"a\"	\n"
			"	.align 4			\n"
			"	.word   14b,4b			\n"
			"	.word   15b,4b			\n"
			"	.previous			\n"
			: "+r" (res), "+r"(to), "+r"(from),
			  "=r"(tmp1), "=r"(tmp2)
			:
			: "memory");
		}
		if (orig_n / 4) {
			orig_n = orig_n % 4;

			__asm__ __volatile__(
			"16:	ld.ab   %3, [%2,4]		\n"
			"	st.ab   %3, [%1,4]		\n"
			"	sub     %0,%0,4			\n"
			"32:	;nop				\n"
			"	.section .fixup, \"ax\"		\n"
			"	.align 4			\n"
			"4:	j   32b				\n"
			"	.previous			\n"
			"	.section __ex_table, \"a\"	\n"
			"	.align 4			\n"
			"	.word   16b,4b			\n"
			"	.previous			\n"
			: "+r" (res), "+r"(to), "+r"(from), "=r"(tmp1)
			:
			: "memory");
		}
		if (orig_n / 2) {
			orig_n = orig_n % 2;

			__asm__ __volatile__(
			"17:	ldw.ab   %3, [%2,2]		\n"
			"	stw.ab   %3, [%1,2]		\n"
			"	sub      %0,%0,2		\n"
			"33:	;nop				\n"
			"	.section .fixup, \"ax\"		\n"
			"	.align 4			\n"
			"4:	j   33b				\n"
			"	.previous			\n"
			"	.section __ex_table, \"a\"	\n"
			"	.align 4			\n"
			"	.word   17b,4b			\n"
			"	.previous			\n"
			: "+r" (res), "+r"(to), "+r"(from), "=r"(tmp1)
			:
			: "memory");
		}
		if (orig_n & 1) {
			__asm__ __volatile__(
			"18:	ldb.ab   %3, [%2,2]		\n"
			"	stb.ab   %3, [%1,2]		\n"
			"	sub      %0,%0,1		\n"
			"34:	; nop				\n"
			"	.section .fixup, \"ax\"		\n"
			"	.align 4			\n"
			"4:	j   34b				\n"
			"	.previous			\n"
			"	.section __ex_table, \"a\"	\n"
			"	.align 4			\n"
			"	.word   18b,4b			\n"
			"	.previous			\n"
			: "+r" (res), "+r"(to), "+r"(from), "=r"(tmp1)
			:
			: "memory");
		}
	} else {  /* n is NOT constant, so laddered copy of 16x,8,4,2,1  */

		__asm__ __volatile__(
		"	mov %0,%3			\n"
		"	lsr.f   lp_count, %3,4		\n"  /* 16x bytes */
		"	lpnz    3f			\n"
		"1:	ld.ab   %5, [%2, 4]		\n"
		"11:	ld.ab   %6, [%2, 4]		\n"
		"12:	ld.ab   %7, [%2, 4]		\n"
		"13:	ld.ab   %8, [%2, 4]		\n"
		"	st.ab   %5, [%1, 4]		\n"
		"	st.ab   %6, [%1, 4]		\n"
		"	st.ab   %7, [%1, 4]		\n"
		"	st.ab   %8, [%1, 4]		\n"
		"	sub     %0,%0,16		\n"
		"3:	and.f   %3,%3,0xf		\n"  /* stragglers */
		"	bz      34f			\n"
		"	bbit0   %3,3,31f		\n"  /* 8 bytes left */
		"14:	ld.ab   %5, [%2,4]		\n"
		"15:	ld.ab   %6, [%2,4]		\n"
		"	st.ab   %5, [%1,4]		\n"
		"	st.ab   %6, [%1,4]		\n"
		"	sub.f   %0,%0,8			\n"
		"31:	bbit0   %3,2,32f		\n"  /* 4 bytes left */
		"16:	ld.ab   %5, [%2,4]		\n"
		"	st.ab   %5, [%1,4]		\n"
		"	sub.f   %0,%0,4			\n"
		"32:	bbit0   %3,1,33f		\n"  /* 2 bytes left */
		"17:	ldw.ab  %5, [%2,2]		\n"
		"	stw.ab  %5, [%1,2]		\n"
		"	sub.f   %0,%0,2			\n"
		"33:	bbit0   %3,0,34f		\n"
		"18:	ldb.ab  %5, [%2,1]		\n"  /* 1 byte left */
		"	stb.ab  %5, [%1,1]		\n"
		"	sub.f   %0,%0,1			\n"
		"34:	;nop				\n"
		"	.section .fixup, \"ax\"		\n"
		"	.align 4			\n"
		"4:	j   34b				\n"
		"	.previous			\n"
		"	.section __ex_table, \"a\"	\n"
		"	.align 4			\n"
		"	.word   1b, 4b			\n"
		"	.word   11b,4b			\n"
		"	.word   12b,4b			\n"
		"	.word   13b,4b			\n"
		"	.word   14b,4b			\n"
		"	.word   15b,4b			\n"
		"	.word   16b,4b			\n"
		"	.word   17b,4b			\n"
		"	.word   18b,4b			\n"
		"	.previous			\n"
		: "=r" (res), "+r"(to), "+r"(from), "+r"(n), "=r"(val),
		  "=r"(tmp1), "=r"(tmp2), "=r"(tmp3), "=r"(tmp4)
		:
		: "lp_count", "memory");
	}

	return res;
}

extern unsigned long slowpath_copy_to_user(void __user *to, const void *from,
					   unsigned long n);

static inline unsigned long
__arc_copy_to_user(void __user *to, const void *from, unsigned long n)
{
	long res = 0;
	char val;
	unsigned long tmp1, tmp2, tmp3, tmp4;
	unsigned long orig_n = n;

	if (n == 0)
		return 0;

	/* unaligned */
	if (((unsigned long)to & 0x3) || ((unsigned long)from & 0x3)) {

		unsigned char tmp;

		__asm__ __volatile__(
		"	mov.f   lp_count, %0		\n"
		"	lpnz 3f				\n"
		"	ldb.ab  %1, [%3, 1]		\n"
		"1:	stb.ab  %1, [%2, 1]		\n"
		"	sub     %0, %0, 1		\n"
		"3:	;nop				\n"
		"	.section .fixup, \"ax\"		\n"
		"	.align 4			\n"
		"4:	j   3b				\n"
		"	.previous			\n"
		"	.section __ex_table, \"a\"	\n"
		"	.align 4			\n"
		"	.word   1b, 4b			\n"
		"	.previous			\n"

		: "+r" (n),
		/* Note as an '&' earlyclobber operand to make sure the
		 * temporary register inside the loop is not the same as
		 * FROM or TO.
		 */
		  "=&r" (tmp), "+r" (to), "+r" (from)
		:
		: "lp_count", "lp_start", "lp_end", "memory");

		return n;
	}

	if (__builtin_constant_p(orig_n)) {
		res = orig_n;

		if (orig_n / 16) {
			orig_n = orig_n % 16;

			__asm__ __volatile__(
			"	lsr lp_count, %7,4		\n"
			"	lp  3f				\n"
			"	ld.ab %3, [%2, 4]		\n"
			"	ld.ab %4, [%2, 4]		\n"
			"	ld.ab %5, [%2, 4]		\n"
			"	ld.ab %6, [%2, 4]		\n"
			"1:	st.ab %3, [%1, 4]		\n"
			"11:	st.ab %4, [%1, 4]		\n"
			"12:	st.ab %5, [%1, 4]		\n"
			"13:	st.ab %6, [%1, 4]		\n"
			"	sub   %0, %0, 16		\n"
			"3:;nop					\n"
			"	.section .fixup, \"ax\"		\n"
			"	.align 4			\n"
			"4:	j   3b				\n"
			"	.previous			\n"
			"	.section __ex_table, \"a\"	\n"
			"	.align 4			\n"
			"	.word   1b, 4b			\n"
			"	.word   11b,4b			\n"
			"	.word   12b,4b			\n"
			"	.word   13b,4b			\n"
			"	.previous			\n"
			: "+r" (res), "+r"(to), "+r"(from),
			  "=r"(tmp1), "=r"(tmp2), "=r"(tmp3), "=r"(tmp4)
			: "ir"(n)
			: "lp_count", "memory");
		}
		if (orig_n / 8) {
			orig_n = orig_n % 8;

			__asm__ __volatile__(
			"	ld.ab   %3, [%2,4]		\n"
			"	ld.ab   %4, [%2,4]		\n"
			"14:	st.ab   %3, [%1,4]		\n"
			"15:	st.ab   %4, [%1,4]		\n"
			"	sub     %0, %0, 8		\n"
			"31:;nop				\n"
			"	.section .fixup, \"ax\"		\n"
			"	.align 4			\n"
			"4:	j   31b				\n"
			"	.previous			\n"
			"	.section __ex_table, \"a\"	\n"
			"	.align 4			\n"
			"	.word   14b,4b			\n"
			"	.word   15b,4b			\n"
			"	.previous			\n"
			: "+r" (res), "+r"(to), "+r"(from),
			  "=r"(tmp1), "=r"(tmp2)
			:
			: "memory");
		}
		if (orig_n / 4) {
			orig_n = orig_n % 4;

			__asm__ __volatile__(
			"	ld.ab   %3, [%2,4]		\n"
			"16:	st.ab   %3, [%1,4]		\n"
			"	sub     %0, %0, 4		\n"
			"32:;nop				\n"
			"	.section .fixup, \"ax\"		\n"
			"	.align 4			\n"
			"4:	j   32b				\n"
			"	.previous			\n"
			"	.section __ex_table, \"a\"	\n"
			"	.align 4			\n"
			"	.word   16b,4b			\n"
			"	.previous			\n"
			: "+r" (res), "+r"(to), "+r"(from), "=r"(tmp1)
			:
			: "memory");
		}
		if (orig_n / 2) {
			orig_n = orig_n % 2;

			__asm__ __volatile__(
			"	ldw.ab    %3, [%2,2]		\n"
			"17:	stw.ab    %3, [%1,2]		\n"
			"	sub       %0, %0, 2		\n"
			"33:;nop				\n"
			"	.section .fixup, \"ax\"		\n"
			"	.align 4			\n"
			"4:	j   33b				\n"
			"	.previous			\n"
			"	.section __ex_table, \"a\"	\n"
			"	.align 4			\n"
			"	.word   17b,4b			\n"
			"	.previous			\n"
			: "+r" (res), "+r"(to), "+r"(from), "=r"(tmp1)
			:
			: "memory");
		}
		if (orig_n & 1) {
			__asm__ __volatile__(
			"	ldb.ab  %3, [%2,1]		\n"
			"18:	stb.ab  %3, [%1,1]		\n"
			"	sub     %0, %0, 1		\n"
			"34:	;nop				\n"
			"	.section .fixup, \"ax\"		\n"
			"	.align 4			\n"
			"4:	j   34b				\n"
			"	.previous			\n"
			"	.section __ex_table, \"a\"	\n"
			"	.align 4			\n"
			"	.word   18b,4b			\n"
			"	.previous			\n"
			: "+r" (res), "+r"(to), "+r"(from), "=r"(tmp1)
			:
			: "memory");
		}
	} else {  /* n is NOT constant, so laddered copy of 16x,8,4,2,1  */

		__asm__ __volatile__(
		"	mov   %0,%3			\n"
		"	lsr.f lp_count, %3,4		\n"  /* 16x bytes */
		"	lpnz  3f			\n"
		"	ld.ab %5, [%2, 4]		\n"
		"	ld.ab %6, [%2, 4]		\n"
		"	ld.ab %7, [%2, 4]		\n"
		"	ld.ab %8, [%2, 4]		\n"
		"1:	st.ab %5, [%1, 4]		\n"
		"11:	st.ab %6, [%1, 4]		\n"
		"12:	st.ab %7, [%1, 4]		\n"
		"13:	st.ab %8, [%1, 4]		\n"
		"	sub   %0, %0, 16		\n"
		"3:	and.f %3,%3,0xf			\n" /* stragglers */
		"	bz 34f				\n"
		"	bbit0   %3,3,31f		\n" /* 8 bytes left */
		"	ld.ab   %5, [%2,4]		\n"
		"	ld.ab   %6, [%2,4]		\n"
		"14:	st.ab   %5, [%1,4]		\n"
		"15:	st.ab   %6, [%1,4]		\n"
		"	sub.f   %0, %0, 8		\n"
		"31:	bbit0   %3,2,32f		\n"  /* 4 bytes left */
		"	ld.ab   %5, [%2,4]		\n"
		"16:	st.ab   %5, [%1,4]		\n"
		"	sub.f   %0, %0, 4		\n"
		"32:	bbit0 %3,1,33f			\n"  /* 2 bytes left */
		"	ldw.ab    %5, [%2,2]		\n"
		"17:	stw.ab    %5, [%1,2]		\n"
		"	sub.f %0, %0, 2			\n"
		"33:	bbit0 %3,0,34f			\n"
		"	ldb.ab    %5, [%2,1]		\n"  /* 1 byte left */
		"18:	stb.ab  %5, [%1,1]		\n"
		"	sub.f %0, %0, 1			\n"
		"34:	;nop				\n"
		"	.section .fixup, \"ax\"		\n"
		"	.align 4			\n"
		"4:	j   34b				\n"
		"	.previous			\n"
		"	.section __ex_table, \"a\"	\n"
		"	.align 4			\n"
		"	.word   1b, 4b			\n"
		"	.word   11b,4b			\n"
		"	.word   12b,4b			\n"
		"	.word   13b,4b			\n"
		"	.word   14b,4b			\n"
		"	.word   15b,4b			\n"
		"	.word   16b,4b			\n"
		"	.word   17b,4b			\n"
		"	.word   18b,4b			\n"
		"	.previous			\n"
		: "=r" (res), "+r"(to), "+r"(from), "+r"(n), "=r"(val),
		  "=r"(tmp1), "=r"(tmp2), "=r"(tmp3), "=r"(tmp4)
		:
		: "lp_count", "memory");
	}

	return res;
}

static inline unsigned long __arc_clear_user(void __user *to, unsigned long n)
{
	long res = n;
	unsigned char *d_char = to;

	__asm__ __volatile__(
	"	bbit0   %0, 0, 1f		\n"
	"75:	stb.ab  %2, [%0,1]		\n"
	"	sub %1, %1, 1			\n"
	"1:	bbit0   %0, 1, 2f		\n"
	"76:	stw.ab  %2, [%0,2]		\n"
	"	sub %1, %1, 2			\n"
	"2:	asr.f   lp_count, %1, 2		\n"
	"	lpnz    3f			\n"
	"77:	st.ab   %2, [%0,4]		\n"
	"	sub %1, %1, 4			\n"
	"3:	bbit0   %1, 1, 4f		\n"
	"78:	stw.ab  %2, [%0,2]		\n"
	"	sub %1, %1, 2			\n"
	"4:	bbit0   %1, 0, 5f		\n"
	"79:	stb.ab  %2, [%0,1]		\n"
	"	sub %1, %1, 1			\n"
	"5:					\n"
	"	.section .fixup, \"ax\"		\n"
	"	.align 4			\n"
	"3:	j   5b				\n"
	"	.previous			\n"
	"	.section __ex_table, \"a\"	\n"
	"	.align 4			\n"
	"	.word   75b, 3b			\n"
	"	.word   76b, 3b			\n"
	"	.word   77b, 3b			\n"
	"	.word   78b, 3b			\n"
	"	.word   79b, 3b			\n"
	"	.previous			\n"
	: "+r"(d_char), "+r"(res)
	: "i"(0)
	: "lp_count", "lp_start", "lp_end", "memory");

	return res;
}

static inline long
__arc_strncpy_from_user(char *dst, const char __user *src, long count)
{
	long res = 0;
	char val;

	if (count == 0)
		return 0;

	__asm__ __volatile__(
	"	lp	3f			\n"
	"1:	ldb.ab  %3, [%2, 1]		\n"
	"	breq.d	%3, 0, 3f               \n"
	"	stb.ab  %3, [%1, 1]		\n"
	"	add	%0, %0, 1	# Num of NON NULL bytes copied	\n"
	"3:								\n"
	"	.section .fixup, \"ax\"		\n"
	"	.align 4			\n"
	"4:	mov %0, %4		# sets @res as -EFAULT	\n"
	"	j   3b				\n"
	"	.previous			\n"
	"	.section __ex_table, \"a\"	\n"
	"	.align 4			\n"
	"	.word   1b, 4b			\n"
	"	.previous			\n"
	: "+r"(res), "+r"(dst), "+r"(src), "=r"(val)
	: "g"(-EFAULT), "l"(count)
	: "memory");

	return res;
}

static inline long __arc_strnlen_user(const char __user *s, long n)
{
	long res, tmp1, cnt;
	char val;

	__asm__ __volatile__(
	"	mov %2, %1			\n"
	"1:	ldb.ab  %3, [%0, 1]		\n"
	"	breq.d  %3, 0, 2f		\n"
	"	sub.f   %2, %2, 1		\n"
	"	bnz 1b				\n"
	"	sub %2, %2, 1			\n"
	"2:	sub %0, %1, %2			\n"
	"3:	;nop				\n"
	"	.section .fixup, \"ax\"		\n"
	"	.align 4			\n"
	"4:	mov %0, 0			\n"
	"	j   3b				\n"
	"	.previous			\n"
	"	.section __ex_table, \"a\"	\n"
	"	.align 4			\n"
	"	.word 1b, 4b			\n"
	"	.previous			\n"
	: "=r"(res), "=r"(tmp1), "=r"(cnt), "=r"(val)
	: "0"(s), "1"(n)
	: "memory");

	return res;
}

#ifndef CONFIG_CC_OPTIMIZE_FOR_SIZE
#define __copy_from_user(t, f, n)	__arc_copy_from_user(t, f, n)
#define __copy_to_user(t, f, n)		__arc_copy_to_user(t, f, n)
#define __clear_user(d, n)		__arc_clear_user(d, n)
#define __strncpy_from_user(d, s, n)	__arc_strncpy_from_user(d, s, n)
#define __strnlen_user(s, n)		__arc_strnlen_user(s, n)
#else
extern long arc_copy_from_user_noinline(void *to, const void __user * from,
		unsigned long n);
extern long arc_copy_to_user_noinline(void __user *to, const void *from,
		unsigned long n);
extern unsigned long arc_clear_user_noinline(void __user *to,
		unsigned long n);
extern long arc_strncpy_from_user_noinline (char *dst, const char __user *src,
		long count);
extern long arc_strnlen_user_noinline(const char __user *src, long n);

#define __copy_from_user(t, f, n)	arc_copy_from_user_noinline(t, f, n)
#define __copy_to_user(t, f, n)		arc_copy_to_user_noinline(t, f, n)
#define __clear_user(d, n)		arc_clear_user_noinline(d, n)
#define __strncpy_from_user(d, s, n)	arc_strncpy_from_user_noinline(d, s, n)
#define __strnlen_user(s, n)		arc_strnlen_user_noinline(s, n)

#endif

#include <asm-generic/uaccess.h>

extern int fixup_exception(struct pt_regs *regs);

#endif
OpenPOWER on IntegriCloud