xref: /openbmc/linux/arch/arc/include/asm/uaccess.h (revision f1575595)
1 /*
2  * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
3  *
4  * This program is free software; you can redistribute it and/or modify
5  * it under the terms of the GNU General Public License version 2 as
6  * published by the Free Software Foundation.
7  *
8  * vineetg: June 2010
9  *    -__clear_user( ) called multiple times during elf load was byte loop
10  *    converted to do as much word clear as possible.
11  *
12  * vineetg: Dec 2009
13  *    -Hand crafted constant propagation for "constant" copy sizes
14  *    -stock kernel shrunk by 33K at -O3
15  *
16  * vineetg: Sept 2009
17  *    -Added option to (UN)inline copy_(to|from)_user to reduce code sz
18  *    -kernel shrunk by 200K even at -O3 (gcc 4.2.1)
19  *    -Enabled when doing -Os
20  *
21  * Amit Bhor, Sameer Dhavale: Codito Technologies 2004
22  */
23 
24 #ifndef _ASM_ARC_UACCESS_H
25 #define _ASM_ARC_UACCESS_H
26 
27 #include <linux/string.h>	/* for generic string functions */
28 
29 
30 #define __kernel_ok		(uaccess_kernel())
31 
32 /*
33  * Algorithmically, for __user_ok() we want do:
34  * 	(start < TASK_SIZE) && (start+len < TASK_SIZE)
35  * where TASK_SIZE could either be retrieved from thread_info->addr_limit or
36  * emitted directly in code.
37  *
38  * This can however be rewritten as follows:
39  *	(len <= TASK_SIZE) && (start+len < TASK_SIZE)
40  *
41  * Because it essentially checks if buffer end is within limit and @len is
42  * non-ngeative, which implies that buffer start will be within limit too.
43  *
44  * The reason for rewriting being, for majority of cases, @len is generally
45  * compile time constant, causing first sub-expression to be compile time
46  * subsumed.
47  *
48  * The second part would generate weird large LIMMs e.g. (0x6000_0000 - 0x10),
49  * so we check for TASK_SIZE using get_fs() since the addr_limit load from mem
50  * would already have been done at this call site for __kernel_ok()
51  *
52  */
53 #define __user_ok(addr, sz)	(((sz) <= TASK_SIZE) && \
54 				 ((addr) <= (get_fs() - (sz))))
55 #define __access_ok(addr, sz)	(unlikely(__kernel_ok) || \
56 				 likely(__user_ok((addr), (sz))))
57 
58 /*********** Single byte/hword/word copies ******************/
59 
60 #define __get_user_fn(sz, u, k)					\
61 ({								\
62 	long __ret = 0;	/* success by default */	\
63 	switch (sz) {						\
64 	case 1: __arc_get_user_one(*(k), u, "ldb", __ret); break;	\
65 	case 2: __arc_get_user_one(*(k), u, "ldw", __ret); break;	\
66 	case 4: __arc_get_user_one(*(k), u, "ld", __ret);  break;	\
67 	case 8: __arc_get_user_one_64(*(k), u, __ret);     break;	\
68 	}							\
69 	__ret;							\
70 })
71 
72 /*
73  * Returns 0 on success, -EFAULT if not.
74  * @ret already contains 0 - given that errors will be less likely
75  * (hence +r asm constraint below).
76  * In case of error, fixup code will make it -EFAULT
77  */
78 #define __arc_get_user_one(dst, src, op, ret)	\
79 	__asm__ __volatile__(                   \
80 	"1:	"op"    %1,[%2]\n"		\
81 	"2:	;nop\n"				\
82 	"	.section .fixup, \"ax\"\n"	\
83 	"	.align 4\n"			\
84 	"3:	# return -EFAULT\n"		\
85 	"	mov %0, %3\n"			\
86 	"	# zero out dst ptr\n"		\
87 	"	mov %1,  0\n"			\
88 	"	j   2b\n"			\
89 	"	.previous\n"			\
90 	"	.section __ex_table, \"a\"\n"	\
91 	"	.align 4\n"			\
92 	"	.word 1b,3b\n"			\
93 	"	.previous\n"			\
94 						\
95 	: "+r" (ret), "=r" (dst)		\
96 	: "r" (src), "ir" (-EFAULT))
97 
98 #define __arc_get_user_one_64(dst, src, ret)	\
99 	__asm__ __volatile__(                   \
100 	"1:	ld   %1,[%2]\n"			\
101 	"4:	ld  %R1,[%2, 4]\n"		\
102 	"2:	;nop\n"				\
103 	"	.section .fixup, \"ax\"\n"	\
104 	"	.align 4\n"			\
105 	"3:	# return -EFAULT\n"		\
106 	"	mov %0, %3\n"			\
107 	"	# zero out dst ptr\n"		\
108 	"	mov %1,  0\n"			\
109 	"	mov %R1, 0\n"			\
110 	"	j   2b\n"			\
111 	"	.previous\n"			\
112 	"	.section __ex_table, \"a\"\n"	\
113 	"	.align 4\n"			\
114 	"	.word 1b,3b\n"			\
115 	"	.word 4b,3b\n"			\
116 	"	.previous\n"			\
117 						\
118 	: "+r" (ret), "=r" (dst)		\
119 	: "r" (src), "ir" (-EFAULT))
120 
121 #define __put_user_fn(sz, u, k)					\
122 ({								\
123 	long __ret = 0;	/* success by default */	\
124 	switch (sz) {						\
125 	case 1: __arc_put_user_one(*(k), u, "stb", __ret); break;	\
126 	case 2: __arc_put_user_one(*(k), u, "stw", __ret); break;	\
127 	case 4: __arc_put_user_one(*(k), u, "st", __ret);  break;	\
128 	case 8: __arc_put_user_one_64(*(k), u, __ret);     break;	\
129 	}							\
130 	__ret;							\
131 })
132 
133 #define __arc_put_user_one(src, dst, op, ret)	\
134 	__asm__ __volatile__(                   \
135 	"1:	"op"    %1,[%2]\n"		\
136 	"2:	;nop\n"				\
137 	"	.section .fixup, \"ax\"\n"	\
138 	"	.align 4\n"			\
139 	"3:	mov %0, %3\n"			\
140 	"	j   2b\n"			\
141 	"	.previous\n"			\
142 	"	.section __ex_table, \"a\"\n"	\
143 	"	.align 4\n"			\
144 	"	.word 1b,3b\n"			\
145 	"	.previous\n"			\
146 						\
147 	: "+r" (ret)				\
148 	: "r" (src), "r" (dst), "ir" (-EFAULT))
149 
150 #define __arc_put_user_one_64(src, dst, ret)	\
151 	__asm__ __volatile__(                   \
152 	"1:	st   %1,[%2]\n"			\
153 	"4:	st  %R1,[%2, 4]\n"		\
154 	"2:	;nop\n"				\
155 	"	.section .fixup, \"ax\"\n"	\
156 	"	.align 4\n"			\
157 	"3:	mov %0, %3\n"			\
158 	"	j   2b\n"			\
159 	"	.previous\n"			\
160 	"	.section __ex_table, \"a\"\n"	\
161 	"	.align 4\n"			\
162 	"	.word 1b,3b\n"			\
163 	"	.word 4b,3b\n"			\
164 	"	.previous\n"			\
165 						\
166 	: "+r" (ret)				\
167 	: "r" (src), "r" (dst), "ir" (-EFAULT))
168 
169 
170 static inline unsigned long
171 raw_copy_from_user(void *to, const void __user *from, unsigned long n)
172 {
173 	long res = 0;
174 	char val;
175 	unsigned long tmp1, tmp2, tmp3, tmp4;
176 	unsigned long orig_n = n;
177 
178 	if (n == 0)
179 		return 0;
180 
181 	/* unaligned */
182 	if (((unsigned long)to & 0x3) || ((unsigned long)from & 0x3)) {
183 
184 		unsigned char tmp;
185 
186 		__asm__ __volatile__ (
187 		"	mov.f   lp_count, %0		\n"
188 		"	lpnz 2f				\n"
189 		"1:	ldb.ab  %1, [%3, 1]		\n"
190 		"	stb.ab  %1, [%2, 1]		\n"
191 		"	sub     %0,%0,1			\n"
192 		"2:	;nop				\n"
193 		"	.section .fixup, \"ax\"		\n"
194 		"	.align 4			\n"
195 		"3:	j   2b				\n"
196 		"	.previous			\n"
197 		"	.section __ex_table, \"a\"	\n"
198 		"	.align 4			\n"
199 		"	.word   1b, 3b			\n"
200 		"	.previous			\n"
201 
202 		: "+r" (n),
203 		/*
204 		 * Note as an '&' earlyclobber operand to make sure the
205 		 * temporary register inside the loop is not the same as
206 		 *  FROM or TO.
207 		*/
208 		  "=&r" (tmp), "+r" (to), "+r" (from)
209 		:
210 		: "lp_count", "lp_start", "lp_end", "memory");
211 
212 		return n;
213 	}
214 
215 	/*
216 	 * Hand-crafted constant propagation to reduce code sz of the
217 	 * laddered copy 16x,8,4,2,1
218 	 */
219 	if (__builtin_constant_p(orig_n)) {
220 		res = orig_n;
221 
222 		if (orig_n / 16) {
223 			orig_n = orig_n % 16;
224 
225 			__asm__ __volatile__(
226 			"	lsr   lp_count, %7,4		\n"
227 			"	lp    3f			\n"
228 			"1:	ld.ab   %3, [%2, 4]		\n"
229 			"11:	ld.ab   %4, [%2, 4]		\n"
230 			"12:	ld.ab   %5, [%2, 4]		\n"
231 			"13:	ld.ab   %6, [%2, 4]		\n"
232 			"	st.ab   %3, [%1, 4]		\n"
233 			"	st.ab   %4, [%1, 4]		\n"
234 			"	st.ab   %5, [%1, 4]		\n"
235 			"	st.ab   %6, [%1, 4]		\n"
236 			"	sub     %0,%0,16		\n"
237 			"3:	;nop				\n"
238 			"	.section .fixup, \"ax\"		\n"
239 			"	.align 4			\n"
240 			"4:	j   3b				\n"
241 			"	.previous			\n"
242 			"	.section __ex_table, \"a\"	\n"
243 			"	.align 4			\n"
244 			"	.word   1b, 4b			\n"
245 			"	.word   11b,4b			\n"
246 			"	.word   12b,4b			\n"
247 			"	.word   13b,4b			\n"
248 			"	.previous			\n"
249 			: "+r" (res), "+r"(to), "+r"(from),
250 			  "=r"(tmp1), "=r"(tmp2), "=r"(tmp3), "=r"(tmp4)
251 			: "ir"(n)
252 			: "lp_count", "memory");
253 		}
254 		if (orig_n / 8) {
255 			orig_n = orig_n % 8;
256 
257 			__asm__ __volatile__(
258 			"14:	ld.ab   %3, [%2,4]		\n"
259 			"15:	ld.ab   %4, [%2,4]		\n"
260 			"	st.ab   %3, [%1,4]		\n"
261 			"	st.ab   %4, [%1,4]		\n"
262 			"	sub     %0,%0,8			\n"
263 			"31:	;nop				\n"
264 			"	.section .fixup, \"ax\"		\n"
265 			"	.align 4			\n"
266 			"4:	j   31b				\n"
267 			"	.previous			\n"
268 			"	.section __ex_table, \"a\"	\n"
269 			"	.align 4			\n"
270 			"	.word   14b,4b			\n"
271 			"	.word   15b,4b			\n"
272 			"	.previous			\n"
273 			: "+r" (res), "+r"(to), "+r"(from),
274 			  "=r"(tmp1), "=r"(tmp2)
275 			:
276 			: "memory");
277 		}
278 		if (orig_n / 4) {
279 			orig_n = orig_n % 4;
280 
281 			__asm__ __volatile__(
282 			"16:	ld.ab   %3, [%2,4]		\n"
283 			"	st.ab   %3, [%1,4]		\n"
284 			"	sub     %0,%0,4			\n"
285 			"32:	;nop				\n"
286 			"	.section .fixup, \"ax\"		\n"
287 			"	.align 4			\n"
288 			"4:	j   32b				\n"
289 			"	.previous			\n"
290 			"	.section __ex_table, \"a\"	\n"
291 			"	.align 4			\n"
292 			"	.word   16b,4b			\n"
293 			"	.previous			\n"
294 			: "+r" (res), "+r"(to), "+r"(from), "=r"(tmp1)
295 			:
296 			: "memory");
297 		}
298 		if (orig_n / 2) {
299 			orig_n = orig_n % 2;
300 
301 			__asm__ __volatile__(
302 			"17:	ldw.ab   %3, [%2,2]		\n"
303 			"	stw.ab   %3, [%1,2]		\n"
304 			"	sub      %0,%0,2		\n"
305 			"33:	;nop				\n"
306 			"	.section .fixup, \"ax\"		\n"
307 			"	.align 4			\n"
308 			"4:	j   33b				\n"
309 			"	.previous			\n"
310 			"	.section __ex_table, \"a\"	\n"
311 			"	.align 4			\n"
312 			"	.word   17b,4b			\n"
313 			"	.previous			\n"
314 			: "+r" (res), "+r"(to), "+r"(from), "=r"(tmp1)
315 			:
316 			: "memory");
317 		}
318 		if (orig_n & 1) {
319 			__asm__ __volatile__(
320 			"18:	ldb.ab   %3, [%2,2]		\n"
321 			"	stb.ab   %3, [%1,2]		\n"
322 			"	sub      %0,%0,1		\n"
323 			"34:	; nop				\n"
324 			"	.section .fixup, \"ax\"		\n"
325 			"	.align 4			\n"
326 			"4:	j   34b				\n"
327 			"	.previous			\n"
328 			"	.section __ex_table, \"a\"	\n"
329 			"	.align 4			\n"
330 			"	.word   18b,4b			\n"
331 			"	.previous			\n"
332 			: "+r" (res), "+r"(to), "+r"(from), "=r"(tmp1)
333 			:
334 			: "memory");
335 		}
336 	} else {  /* n is NOT constant, so laddered copy of 16x,8,4,2,1  */
337 
338 		__asm__ __volatile__(
339 		"	mov %0,%3			\n"
340 		"	lsr.f   lp_count, %3,4		\n"  /* 16x bytes */
341 		"	lpnz    3f			\n"
342 		"1:	ld.ab   %5, [%2, 4]		\n"
343 		"11:	ld.ab   %6, [%2, 4]		\n"
344 		"12:	ld.ab   %7, [%2, 4]		\n"
345 		"13:	ld.ab   %8, [%2, 4]		\n"
346 		"	st.ab   %5, [%1, 4]		\n"
347 		"	st.ab   %6, [%1, 4]		\n"
348 		"	st.ab   %7, [%1, 4]		\n"
349 		"	st.ab   %8, [%1, 4]		\n"
350 		"	sub     %0,%0,16		\n"
351 		"3:	and.f   %3,%3,0xf		\n"  /* stragglers */
352 		"	bz      34f			\n"
353 		"	bbit0   %3,3,31f		\n"  /* 8 bytes left */
354 		"14:	ld.ab   %5, [%2,4]		\n"
355 		"15:	ld.ab   %6, [%2,4]		\n"
356 		"	st.ab   %5, [%1,4]		\n"
357 		"	st.ab   %6, [%1,4]		\n"
358 		"	sub.f   %0,%0,8			\n"
359 		"31:	bbit0   %3,2,32f		\n"  /* 4 bytes left */
360 		"16:	ld.ab   %5, [%2,4]		\n"
361 		"	st.ab   %5, [%1,4]		\n"
362 		"	sub.f   %0,%0,4			\n"
363 		"32:	bbit0   %3,1,33f		\n"  /* 2 bytes left */
364 		"17:	ldw.ab  %5, [%2,2]		\n"
365 		"	stw.ab  %5, [%1,2]		\n"
366 		"	sub.f   %0,%0,2			\n"
367 		"33:	bbit0   %3,0,34f		\n"
368 		"18:	ldb.ab  %5, [%2,1]		\n"  /* 1 byte left */
369 		"	stb.ab  %5, [%1,1]		\n"
370 		"	sub.f   %0,%0,1			\n"
371 		"34:	;nop				\n"
372 		"	.section .fixup, \"ax\"		\n"
373 		"	.align 4			\n"
374 		"4:	j   34b				\n"
375 		"	.previous			\n"
376 		"	.section __ex_table, \"a\"	\n"
377 		"	.align 4			\n"
378 		"	.word   1b, 4b			\n"
379 		"	.word   11b,4b			\n"
380 		"	.word   12b,4b			\n"
381 		"	.word   13b,4b			\n"
382 		"	.word   14b,4b			\n"
383 		"	.word   15b,4b			\n"
384 		"	.word   16b,4b			\n"
385 		"	.word   17b,4b			\n"
386 		"	.word   18b,4b			\n"
387 		"	.previous			\n"
388 		: "=r" (res), "+r"(to), "+r"(from), "+r"(n), "=r"(val),
389 		  "=r"(tmp1), "=r"(tmp2), "=r"(tmp3), "=r"(tmp4)
390 		:
391 		: "lp_count", "memory");
392 	}
393 
394 	return res;
395 }
396 
397 static inline unsigned long
398 raw_copy_to_user(void __user *to, const void *from, unsigned long n)
399 {
400 	long res = 0;
401 	char val;
402 	unsigned long tmp1, tmp2, tmp3, tmp4;
403 	unsigned long orig_n = n;
404 
405 	if (n == 0)
406 		return 0;
407 
408 	/* unaligned */
409 	if (((unsigned long)to & 0x3) || ((unsigned long)from & 0x3)) {
410 
411 		unsigned char tmp;
412 
413 		__asm__ __volatile__(
414 		"	mov.f   lp_count, %0		\n"
415 		"	lpnz 3f				\n"
416 		"	ldb.ab  %1, [%3, 1]		\n"
417 		"1:	stb.ab  %1, [%2, 1]		\n"
418 		"	sub     %0, %0, 1		\n"
419 		"3:	;nop				\n"
420 		"	.section .fixup, \"ax\"		\n"
421 		"	.align 4			\n"
422 		"4:	j   3b				\n"
423 		"	.previous			\n"
424 		"	.section __ex_table, \"a\"	\n"
425 		"	.align 4			\n"
426 		"	.word   1b, 4b			\n"
427 		"	.previous			\n"
428 
429 		: "+r" (n),
430 		/* Note as an '&' earlyclobber operand to make sure the
431 		 * temporary register inside the loop is not the same as
432 		 * FROM or TO.
433 		 */
434 		  "=&r" (tmp), "+r" (to), "+r" (from)
435 		:
436 		: "lp_count", "lp_start", "lp_end", "memory");
437 
438 		return n;
439 	}
440 
441 	if (__builtin_constant_p(orig_n)) {
442 		res = orig_n;
443 
444 		if (orig_n / 16) {
445 			orig_n = orig_n % 16;
446 
447 			__asm__ __volatile__(
448 			"	lsr lp_count, %7,4		\n"
449 			"	lp  3f				\n"
450 			"	ld.ab %3, [%2, 4]		\n"
451 			"	ld.ab %4, [%2, 4]		\n"
452 			"	ld.ab %5, [%2, 4]		\n"
453 			"	ld.ab %6, [%2, 4]		\n"
454 			"1:	st.ab %3, [%1, 4]		\n"
455 			"11:	st.ab %4, [%1, 4]		\n"
456 			"12:	st.ab %5, [%1, 4]		\n"
457 			"13:	st.ab %6, [%1, 4]		\n"
458 			"	sub   %0, %0, 16		\n"
459 			"3:;nop					\n"
460 			"	.section .fixup, \"ax\"		\n"
461 			"	.align 4			\n"
462 			"4:	j   3b				\n"
463 			"	.previous			\n"
464 			"	.section __ex_table, \"a\"	\n"
465 			"	.align 4			\n"
466 			"	.word   1b, 4b			\n"
467 			"	.word   11b,4b			\n"
468 			"	.word   12b,4b			\n"
469 			"	.word   13b,4b			\n"
470 			"	.previous			\n"
471 			: "+r" (res), "+r"(to), "+r"(from),
472 			  "=r"(tmp1), "=r"(tmp2), "=r"(tmp3), "=r"(tmp4)
473 			: "ir"(n)
474 			: "lp_count", "memory");
475 		}
476 		if (orig_n / 8) {
477 			orig_n = orig_n % 8;
478 
479 			__asm__ __volatile__(
480 			"	ld.ab   %3, [%2,4]		\n"
481 			"	ld.ab   %4, [%2,4]		\n"
482 			"14:	st.ab   %3, [%1,4]		\n"
483 			"15:	st.ab   %4, [%1,4]		\n"
484 			"	sub     %0, %0, 8		\n"
485 			"31:;nop				\n"
486 			"	.section .fixup, \"ax\"		\n"
487 			"	.align 4			\n"
488 			"4:	j   31b				\n"
489 			"	.previous			\n"
490 			"	.section __ex_table, \"a\"	\n"
491 			"	.align 4			\n"
492 			"	.word   14b,4b			\n"
493 			"	.word   15b,4b			\n"
494 			"	.previous			\n"
495 			: "+r" (res), "+r"(to), "+r"(from),
496 			  "=r"(tmp1), "=r"(tmp2)
497 			:
498 			: "memory");
499 		}
500 		if (orig_n / 4) {
501 			orig_n = orig_n % 4;
502 
503 			__asm__ __volatile__(
504 			"	ld.ab   %3, [%2,4]		\n"
505 			"16:	st.ab   %3, [%1,4]		\n"
506 			"	sub     %0, %0, 4		\n"
507 			"32:;nop				\n"
508 			"	.section .fixup, \"ax\"		\n"
509 			"	.align 4			\n"
510 			"4:	j   32b				\n"
511 			"	.previous			\n"
512 			"	.section __ex_table, \"a\"	\n"
513 			"	.align 4			\n"
514 			"	.word   16b,4b			\n"
515 			"	.previous			\n"
516 			: "+r" (res), "+r"(to), "+r"(from), "=r"(tmp1)
517 			:
518 			: "memory");
519 		}
520 		if (orig_n / 2) {
521 			orig_n = orig_n % 2;
522 
523 			__asm__ __volatile__(
524 			"	ldw.ab    %3, [%2,2]		\n"
525 			"17:	stw.ab    %3, [%1,2]		\n"
526 			"	sub       %0, %0, 2		\n"
527 			"33:;nop				\n"
528 			"	.section .fixup, \"ax\"		\n"
529 			"	.align 4			\n"
530 			"4:	j   33b				\n"
531 			"	.previous			\n"
532 			"	.section __ex_table, \"a\"	\n"
533 			"	.align 4			\n"
534 			"	.word   17b,4b			\n"
535 			"	.previous			\n"
536 			: "+r" (res), "+r"(to), "+r"(from), "=r"(tmp1)
537 			:
538 			: "memory");
539 		}
540 		if (orig_n & 1) {
541 			__asm__ __volatile__(
542 			"	ldb.ab  %3, [%2,1]		\n"
543 			"18:	stb.ab  %3, [%1,1]		\n"
544 			"	sub     %0, %0, 1		\n"
545 			"34:	;nop				\n"
546 			"	.section .fixup, \"ax\"		\n"
547 			"	.align 4			\n"
548 			"4:	j   34b				\n"
549 			"	.previous			\n"
550 			"	.section __ex_table, \"a\"	\n"
551 			"	.align 4			\n"
552 			"	.word   18b,4b			\n"
553 			"	.previous			\n"
554 			: "+r" (res), "+r"(to), "+r"(from), "=r"(tmp1)
555 			:
556 			: "memory");
557 		}
558 	} else {  /* n is NOT constant, so laddered copy of 16x,8,4,2,1  */
559 
560 		__asm__ __volatile__(
561 		"	mov   %0,%3			\n"
562 		"	lsr.f lp_count, %3,4		\n"  /* 16x bytes */
563 		"	lpnz  3f			\n"
564 		"	ld.ab %5, [%2, 4]		\n"
565 		"	ld.ab %6, [%2, 4]		\n"
566 		"	ld.ab %7, [%2, 4]		\n"
567 		"	ld.ab %8, [%2, 4]		\n"
568 		"1:	st.ab %5, [%1, 4]		\n"
569 		"11:	st.ab %6, [%1, 4]		\n"
570 		"12:	st.ab %7, [%1, 4]		\n"
571 		"13:	st.ab %8, [%1, 4]		\n"
572 		"	sub   %0, %0, 16		\n"
573 		"3:	and.f %3,%3,0xf			\n" /* stragglers */
574 		"	bz 34f				\n"
575 		"	bbit0   %3,3,31f		\n" /* 8 bytes left */
576 		"	ld.ab   %5, [%2,4]		\n"
577 		"	ld.ab   %6, [%2,4]		\n"
578 		"14:	st.ab   %5, [%1,4]		\n"
579 		"15:	st.ab   %6, [%1,4]		\n"
580 		"	sub.f   %0, %0, 8		\n"
581 		"31:	bbit0   %3,2,32f		\n"  /* 4 bytes left */
582 		"	ld.ab   %5, [%2,4]		\n"
583 		"16:	st.ab   %5, [%1,4]		\n"
584 		"	sub.f   %0, %0, 4		\n"
585 		"32:	bbit0 %3,1,33f			\n"  /* 2 bytes left */
586 		"	ldw.ab    %5, [%2,2]		\n"
587 		"17:	stw.ab    %5, [%1,2]		\n"
588 		"	sub.f %0, %0, 2			\n"
589 		"33:	bbit0 %3,0,34f			\n"
590 		"	ldb.ab    %5, [%2,1]		\n"  /* 1 byte left */
591 		"18:	stb.ab  %5, [%1,1]		\n"
592 		"	sub.f %0, %0, 1			\n"
593 		"34:	;nop				\n"
594 		"	.section .fixup, \"ax\"		\n"
595 		"	.align 4			\n"
596 		"4:	j   34b				\n"
597 		"	.previous			\n"
598 		"	.section __ex_table, \"a\"	\n"
599 		"	.align 4			\n"
600 		"	.word   1b, 4b			\n"
601 		"	.word   11b,4b			\n"
602 		"	.word   12b,4b			\n"
603 		"	.word   13b,4b			\n"
604 		"	.word   14b,4b			\n"
605 		"	.word   15b,4b			\n"
606 		"	.word   16b,4b			\n"
607 		"	.word   17b,4b			\n"
608 		"	.word   18b,4b			\n"
609 		"	.previous			\n"
610 		: "=r" (res), "+r"(to), "+r"(from), "+r"(n), "=r"(val),
611 		  "=r"(tmp1), "=r"(tmp2), "=r"(tmp3), "=r"(tmp4)
612 		:
613 		: "lp_count", "memory");
614 	}
615 
616 	return res;
617 }
618 
619 static inline unsigned long __arc_clear_user(void __user *to, unsigned long n)
620 {
621 	long res = n;
622 	unsigned char *d_char = to;
623 
624 	__asm__ __volatile__(
625 	"	bbit0   %0, 0, 1f		\n"
626 	"75:	stb.ab  %2, [%0,1]		\n"
627 	"	sub %1, %1, 1			\n"
628 	"1:	bbit0   %0, 1, 2f		\n"
629 	"76:	stw.ab  %2, [%0,2]		\n"
630 	"	sub %1, %1, 2			\n"
631 	"2:	asr.f   lp_count, %1, 2		\n"
632 	"	lpnz    3f			\n"
633 	"77:	st.ab   %2, [%0,4]		\n"
634 	"	sub %1, %1, 4			\n"
635 	"3:	bbit0   %1, 1, 4f		\n"
636 	"78:	stw.ab  %2, [%0,2]		\n"
637 	"	sub %1, %1, 2			\n"
638 	"4:	bbit0   %1, 0, 5f		\n"
639 	"79:	stb.ab  %2, [%0,1]		\n"
640 	"	sub %1, %1, 1			\n"
641 	"5:					\n"
642 	"	.section .fixup, \"ax\"		\n"
643 	"	.align 4			\n"
644 	"3:	j   5b				\n"
645 	"	.previous			\n"
646 	"	.section __ex_table, \"a\"	\n"
647 	"	.align 4			\n"
648 	"	.word   75b, 3b			\n"
649 	"	.word   76b, 3b			\n"
650 	"	.word   77b, 3b			\n"
651 	"	.word   78b, 3b			\n"
652 	"	.word   79b, 3b			\n"
653 	"	.previous			\n"
654 	: "+r"(d_char), "+r"(res)
655 	: "i"(0)
656 	: "lp_count", "lp_start", "lp_end", "memory");
657 
658 	return res;
659 }
660 
661 static inline long
662 __arc_strncpy_from_user(char *dst, const char __user *src, long count)
663 {
664 	long res = 0;
665 	char val;
666 
667 	if (count == 0)
668 		return 0;
669 
670 	__asm__ __volatile__(
671 	"	mov	lp_count, %5		\n"
672 	"	lp	3f			\n"
673 	"1:	ldb.ab  %3, [%2, 1]		\n"
674 	"	breq.d	%3, 0, 3f               \n"
675 	"	stb.ab  %3, [%1, 1]		\n"
676 	"	add	%0, %0, 1	# Num of NON NULL bytes copied	\n"
677 	"3:								\n"
678 	"	.section .fixup, \"ax\"		\n"
679 	"	.align 4			\n"
680 	"4:	mov %0, %4		# sets @res as -EFAULT	\n"
681 	"	j   3b				\n"
682 	"	.previous			\n"
683 	"	.section __ex_table, \"a\"	\n"
684 	"	.align 4			\n"
685 	"	.word   1b, 4b			\n"
686 	"	.previous			\n"
687 	: "+r"(res), "+r"(dst), "+r"(src), "=r"(val)
688 	: "g"(-EFAULT), "r"(count)
689 	: "lp_count", "lp_start", "lp_end", "memory");
690 
691 	return res;
692 }
693 
694 static inline long __arc_strnlen_user(const char __user *s, long n)
695 {
696 	long res, tmp1, cnt;
697 	char val;
698 
699 	__asm__ __volatile__(
700 	"	mov %2, %1			\n"
701 	"1:	ldb.ab  %3, [%0, 1]		\n"
702 	"	breq.d  %3, 0, 2f		\n"
703 	"	sub.f   %2, %2, 1		\n"
704 	"	bnz 1b				\n"
705 	"	sub %2, %2, 1			\n"
706 	"2:	sub %0, %1, %2			\n"
707 	"3:	;nop				\n"
708 	"	.section .fixup, \"ax\"		\n"
709 	"	.align 4			\n"
710 	"4:	mov %0, 0			\n"
711 	"	j   3b				\n"
712 	"	.previous			\n"
713 	"	.section __ex_table, \"a\"	\n"
714 	"	.align 4			\n"
715 	"	.word 1b, 4b			\n"
716 	"	.previous			\n"
717 	: "=r"(res), "=r"(tmp1), "=r"(cnt), "=r"(val)
718 	: "0"(s), "1"(n)
719 	: "memory");
720 
721 	return res;
722 }
723 
724 #ifndef CONFIG_CC_OPTIMIZE_FOR_SIZE
725 
726 #define INLINE_COPY_TO_USER
727 #define INLINE_COPY_FROM_USER
728 
729 #define __clear_user(d, n)		__arc_clear_user(d, n)
730 #define __strncpy_from_user(d, s, n)	__arc_strncpy_from_user(d, s, n)
731 #define __strnlen_user(s, n)		__arc_strnlen_user(s, n)
732 #else
733 extern unsigned long arc_clear_user_noinline(void __user *to,
734 		unsigned long n);
735 extern long arc_strncpy_from_user_noinline (char *dst, const char __user *src,
736 		long count);
737 extern long arc_strnlen_user_noinline(const char __user *src, long n);
738 
739 #define __clear_user(d, n)		arc_clear_user_noinline(d, n)
740 #define __strncpy_from_user(d, s, n)	arc_strncpy_from_user_noinline(d, s, n)
741 #define __strnlen_user(s, n)		arc_strnlen_user_noinline(s, n)
742 
743 #endif
744 
745 #include <asm-generic/uaccess.h>
746 
747 #endif
748