[linux-2.6-block.git] / arch / arc / include / asm / uaccess.h

/*
 * 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:	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" (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:	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" (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
Commit	Line	Data
43697cb0 VG	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/sched.h>
	28	#include <asm/errno.h>
	29	#include <linux/string.h> /* for generic string functions */
	30
	31
	32	#define __kernel_ok (segment_eq(get_fs(), KERNEL_DS))
	33
	34	/*
2547476a	35	* Algorithmically, for __user_ok() we want do:
43697cb0 VG	36	* (start < TASK_SIZE) && (start+len < TASK_SIZE)
	37	* where TASK_SIZE could either be retrieved from thread_info->addr_limit or
	38	* emitted directly in code.
	39	*
	40	* This can however be rewritten as follows:
	41	* (len <= TASK_SIZE) && (start+len < TASK_SIZE)
	42	*
	43	* Because it essentially checks if buffer end is within limit and @len is
	44	* non-ngeative, which implies that buffer start will be within limit too.
	45	*
0752adfd	46	* The reason for rewriting being, for majority of cases, @len is generally
43697cb0 VG	47	* compile time constant, causing first sub-expression to be compile time
	48	* subsumed.
	49	*
	50	* The second part would generate weird large LIMMs e.g. (0x6000_0000 - 0x10),
	51	* so we check for TASK_SIZE using get_fs() since the addr_limit load from mem
	52	* would already have been done at this call site for __kernel_ok()
	53	*
	54	*/
	55	#define __user_ok(addr, sz) (((sz) <= TASK_SIZE) && \
0752adfd	56	((addr) <= (get_fs() - (sz))))
43697cb0 VG	57	#define __access_ok(addr, sz) (unlikely(__kernel_ok) \|\| \
	58	likely(__user_ok((addr), (sz))))
	59
0a5eae45 VG	60	/********* Single byte/hword/word copies ****************/
	61
	62	#define __get_user_fn(sz, u, k) \
	63	({ \
	64	long __ret = 0; /* success by default */ \
	65	switch (sz) { \
	66	case 1: __arc_get_user_one(*(k), u, "ldb", __ret); break; \
	67	case 2: __arc_get_user_one(*(k), u, "ldw", __ret); break; \
	68	case 4: __arc_get_user_one(*(k), u, "ld", __ret); break; \
	69	case 8: __arc_get_user_one_64(*(k), u, __ret); break; \
	70	} \
	71	__ret; \
	72	})
	73
	74	/*
	75	* Returns 0 on success, -EFAULT if not.
	76	* @ret already contains 0 - given that errors will be less likely
	77	* (hence +r asm constraint below).
	78	* In case of error, fixup code will make it -EFAULT
	79	*/
	80	#define __arc_get_user_one(dst, src, op, ret) \
	81	__asm__ __volatile__( \
	82	"1: "op" %1,[%2]\n" \
	83	"2: ;nop\n" \
	84	" .section .fixup, \"ax\"\n" \
	85	" .align 4\n" \
	86	"3: mov %0, %3\n" \
	87	" j 2b\n" \
	88	" .previous\n" \
	89	" .section __ex_table, \"a\"\n" \
	90	" .align 4\n" \
	91	" .word 1b,3b\n" \
	92	" .previous\n" \
	93	\
	94	: "+r" (ret), "=r" (dst) \
	95	: "r" (src), "ir" (-EFAULT))
	96
	97	#define __arc_get_user_one_64(dst, src, ret) \
	98	__asm__ __volatile__( \
	99	"1: ld %1,[%2]\n" \
	100	"4: ld %R1,[%2, 4]\n" \
	101	"2: ;nop\n" \
	102	" .section .fixup, \"ax\"\n" \
	103	" .align 4\n" \
	104	"3: mov %0, %3\n" \
	105	" j 2b\n" \
	106	" .previous\n" \
	107	" .section __ex_table, \"a\"\n" \
	108	" .align 4\n" \
	109	" .word 1b,3b\n" \
	110	" .word 4b,3b\n" \
	111	" .previous\n" \
	112	\
	113	: "+r" (ret), "=r" (dst) \
	114	: "r" (src), "ir" (-EFAULT))
	115
	116	#define __put_user_fn(sz, u, k) \
	117	({ \
	118	long __ret = 0; /* success by default */ \
	119	switch (sz) { \
	120	case 1: __arc_put_user_one(*(k), u, "stb", __ret); break; \
	121	case 2: __arc_put_user_one(*(k), u, "stw", __ret); break; \
	122	case 4: __arc_put_user_one(*(k), u, "st", __ret); break; \
	123	case 8: __arc_put_user_one_64(*(k), u, __ret); break; \
124	} \
125	__ret; \
126	})
127
128	#define __arc_put_user_one(src, dst, op, ret) \
129	__asm__ __volatile__( \
130	"1: "op" %1,[%2]\n" \
131	"2: ;nop\n" \
132	" .section .fixup, \"ax\"\n" \
133	" .align 4\n" \
134	"3: mov %0, %3\n" \
135	" j 2b\n" \
136	" .previous\n" \
137	" .section __ex_table, \"a\"\n" \
138	" .align 4\n" \
139	" .word 1b,3b\n" \
140	" .previous\n" \
141	\
142	: "+r" (ret) \
143	: "r" (src), "r" (dst), "ir" (-EFAULT))
144
145	#define __arc_put_user_one_64(src, dst, ret) \
146	__asm__ __volatile__( \
147	"1: st %1,[%2]\n" \
148	"4: st %R1,[%2, 4]\n" \
149	"2: ;nop\n" \
150	" .section .fixup, \"ax\"\n" \
151	" .align 4\n" \
152	"3: mov %0, %3\n" \
153	" j 2b\n" \
154	" .previous\n" \
155	" .section __ex_table, \"a\"\n" \
156	" .align 4\n" \
157	" .word 1b,3b\n" \
158	" .word 4b,3b\n" \
159	" .previous\n" \
160	\
161	: "+r" (ret) \
162	: "r" (src), "r" (dst), "ir" (-EFAULT))
163
164
43697cb0 VG	165	static inline unsigned long
	166	__arc_copy_from_user(void to, const void __user from, unsigned long n)
	167	{
	168	long res = 0;
	169	char val;
	170	unsigned long tmp1, tmp2, tmp3, tmp4;
	171	unsigned long orig_n = n;
	172
	173	if (n == 0)
	174	return 0;
	175
	176	/* unaligned */
	177	if (((unsigned long)to & 0x3) \|\| ((unsigned long)from & 0x3)) {
	178
	179	unsigned char tmp;
	180
	181	__asm__ __volatile__ (
	182	" mov.f lp_count, %0 \n"
	183	" lpnz 2f \n"
	184	"1: ldb.ab %1, [%3, 1] \n"
	185	" stb.ab %1, [%2, 1] \n"
	186	" sub %0,%0,1 \n"
	187	"2: ;nop \n"
	188	" .section .fixup, \"ax\" \n"
	189	" .align 4 \n"
	190	"3: j 2b \n"
	191	" .previous \n"
	192	" .section __ex_table, \"a\" \n"
	193	" .align 4 \n"
	194	" .word 1b, 3b \n"
	195	" .previous \n"
	196
	197	: "+r" (n),
	198	/*
	199	* Note as an '&' earlyclobber operand to make sure the
	200	* temporary register inside the loop is not the same as
	201	* FROM or TO.
	202	*/
	203	"=&r" (tmp), "+r" (to), "+r" (from)
	204	:
	205	: "lp_count", "lp_start", "lp_end", "memory");
	206
	207	return n;
	208	}
	209
	210	/*
	211	* Hand-crafted constant propagation to reduce code sz of the
	212	* laddered copy 16x,8,4,2,1
	213	*/
	214	if (__builtin_constant_p(orig_n)) {
	215	res = orig_n;
	216
	217	if (orig_n / 16) {
	218	orig_n = orig_n % 16;
	219
	220	__asm__ __volatile__(
	221	" lsr lp_count, %7,4 \n"
	222	" lp 3f \n"
	223	"1: ld.ab %3, [%2, 4] \n"
	224	"11: ld.ab %4, [%2, 4] \n"
	225	"12: ld.ab %5, [%2, 4] \n"
	226	"13: ld.ab %6, [%2, 4] \n"
	227	" st.ab %3, [%1, 4] \n"
	228	" st.ab %4, [%1, 4] \n"
229	" st.ab %5, [%1, 4] \n"
230	" st.ab %6, [%1, 4] \n"
231	" sub %0,%0,16 \n"
232	"3: ;nop \n"
233	" .section .fixup, \"ax\" \n"
234	" .align 4 \n"
235	"4: j 3b \n"
236	" .previous \n"
237	" .section __ex_table, \"a\" \n"
238	" .align 4 \n"
239	" .word 1b, 4b \n"
240	" .word 11b,4b \n"
241	" .word 12b,4b \n"
242	" .word 13b,4b \n"
243	" .previous \n"
244	: "+r" (res), "+r"(to), "+r"(from),
245	"=r"(tmp1), "=r"(tmp2), "=r"(tmp3), "=r"(tmp4)
246	: "ir"(n)
247	: "lp_count", "memory");
248	}
249	if (orig_n / 8) {
250	orig_n = orig_n % 8;
251
252	__asm__ __volatile__(
253	"14: ld.ab %3, [%2,4] \n"
254	"15: ld.ab %4, [%2,4] \n"
255	" st.ab %3, [%1,4] \n"
256	" st.ab %4, [%1,4] \n"
257	" sub %0,%0,8 \n"
258	"31: ;nop \n"
259	" .section .fixup, \"ax\" \n"
260	" .align 4 \n"
261	"4: j 31b \n"
262	" .previous \n"
263	" .section __ex_table, \"a\" \n"
264	" .align 4 \n"
265	" .word 14b,4b \n"
266	" .word 15b,4b \n"
267	" .previous \n"
268	: "+r" (res), "+r"(to), "+r"(from),
269	"=r"(tmp1), "=r"(tmp2)
270	:
271	: "memory");
272	}
273	if (orig_n / 4) {
274	orig_n = orig_n % 4;
275
276	__asm__ __volatile__(
277	"16: ld.ab %3, [%2,4] \n"
278	" st.ab %3, [%1,4] \n"
279	" sub %0,%0,4 \n"
280	"32: ;nop \n"
281	" .section .fixup, \"ax\" \n"
282	" .align 4 \n"
283	"4: j 32b \n"
284	" .previous \n"
285	" .section __ex_table, \"a\" \n"
286	" .align 4 \n"
287	" .word 16b,4b \n"
288	" .previous \n"
289	: "+r" (res), "+r"(to), "+r"(from), "=r"(tmp1)
290	:
291	: "memory");
292	}
293	if (orig_n / 2) {
294	orig_n = orig_n % 2;
295
296	__asm__ __volatile__(
297	"17: ldw.ab %3, [%2,2] \n"
298	" stw.ab %3, [%1,2] \n"
299	" sub %0,%0,2 \n"
300	"33: ;nop \n"
301	" .section .fixup, \"ax\" \n"
302	" .align 4 \n"
303	"4: j 33b \n"
304	" .previous \n"
305	" .section __ex_table, \"a\" \n"
306	" .align 4 \n"
307	" .word 17b,4b \n"
308	" .previous \n"
309	: "+r" (res), "+r"(to), "+r"(from), "=r"(tmp1)
310	:
311	: "memory");
312	}
313	if (orig_n & 1) {
314	__asm__ __volatile__(
315	"18: ldb.ab %3, [%2,2] \n"
316	" stb.ab %3, [%1,2] \n"
317	" sub %0,%0,1 \n"
318	"34: ; nop \n"
319	" .section .fixup, \"ax\" \n"
320	" .align 4 \n"
321	"4: j 34b \n"
322	" .previous \n"
323	" .section __ex_table, \"a\" \n"
324	" .align 4 \n"
325	" .word 18b,4b \n"
326	" .previous \n"
327	: "+r" (res), "+r"(to), "+r"(from), "=r"(tmp1)
328	:
329	: "memory");
330	}
331	} else { /* n is NOT constant, so laddered copy of 16x,8,4,2,1 */
332
333	__asm__ __volatile__(
334	" mov %0,%3 \n"
335	" lsr.f lp_count, %3,4 \n" /* 16x bytes */
336	" lpnz 3f \n"
337	"1: ld.ab %5, [%2, 4] \n"
338	"11: ld.ab %6, [%2, 4] \n"
339	"12: ld.ab %7, [%2, 4] \n"
340	"13: ld.ab %8, [%2, 4] \n"
341	" st.ab %5, [%1, 4] \n"
342	" st.ab %6, [%1, 4] \n"
343	" st.ab %7, [%1, 4] \n"
344	" st.ab %8, [%1, 4] \n"
345	" sub %0,%0,16 \n"
346	"3: and.f %3,%3,0xf \n" /* stragglers */
347	" bz 34f \n"
348	" bbit0 %3,3,31f \n" /* 8 bytes left */
349	"14: ld.ab %5, [%2,4] \n"
350	"15: ld.ab %6, [%2,4] \n"
351	" st.ab %5, [%1,4] \n"
352	" st.ab %6, [%1,4] \n"
353	" sub.f %0,%0,8 \n"
354	"31: bbit0 %3,2,32f \n" /* 4 bytes left */
355	"16: ld.ab %5, [%2,4] \n"
356	" st.ab %5, [%1,4] \n"
357	" sub.f %0,%0,4 \n"
358	"32: bbit0 %3,1,33f \n" /* 2 bytes left */
359	"17: ldw.ab %5, [%2,2] \n"
360	" stw.ab %5, [%1,2] \n"
361	" sub.f %0,%0,2 \n"
362	"33: bbit0 %3,0,34f \n"
363	"18: ldb.ab %5, [%2,1] \n" /* 1 byte left */
364	" stb.ab %5, [%1,1] \n"
365	" sub.f %0,%0,1 \n"
366	"34: ;nop \n"
367	" .section .fixup, \"ax\" \n"
368	" .align 4 \n"
369	"4: j 34b \n"
370	" .previous \n"
371	" .section __ex_table, \"a\" \n"
372	" .align 4 \n"
373	" .word 1b, 4b \n"
374	" .word 11b,4b \n"
375	" .word 12b,4b \n"
376	" .word 13b,4b \n"
377	" .word 14b,4b \n"
378	" .word 15b,4b \n"
379	" .word 16b,4b \n"
380	" .word 17b,4b \n"
381	" .word 18b,4b \n"
382	" .previous \n"
383	: "=r" (res), "+r"(to), "+r"(from), "+r"(n), "=r"(val),
384	"=r"(tmp1), "=r"(tmp2), "=r"(tmp3), "=r"(tmp4)
385	:
386	: "lp_count", "memory");
387	}
388
389	return res;
390	}
391
392	extern unsigned long slowpath_copy_to_user(void __user to, const void from,
393	unsigned long n);
394
395	static inline unsigned long
396	__arc_copy_to_user(void __user to, const void from, unsigned long n)
397	{
398	long res = 0;
399	char val;
400	unsigned long tmp1, tmp2, tmp3, tmp4;
401	unsigned long orig_n = n;
402
403	if (n == 0)
404	return 0;
405
406	/* unaligned */
407	if (((unsigned long)to & 0x3) \|\| ((unsigned long)from & 0x3)) {
408
409	unsigned char tmp;
410
411	__asm__ __volatile__(
412	" mov.f lp_count, %0 \n"
413	" lpnz 3f \n"
414	" ldb.ab %1, [%3, 1] \n"
415	"1: stb.ab %1, [%2, 1] \n"
416	" sub %0, %0, 1 \n"
417	"3: ;nop \n"
418	" .section .fixup, \"ax\" \n"
419	" .align 4 \n"
420	"4: j 3b \n"
421	" .previous \n"
422	" .section __ex_table, \"a\" \n"
423	" .align 4 \n"
424	" .word 1b, 4b \n"
425	" .previous \n"
426
427	: "+r" (n),
428	/* Note as an '&' earlyclobber operand to make sure the
429	* temporary register inside the loop is not the same as
430	* FROM or TO.
431	*/
432	"=&r" (tmp), "+r" (to), "+r" (from)
433	:
434	: "lp_count", "lp_start", "lp_end", "memory");
435
436	return n;
437	}
438
439	if (__builtin_constant_p(orig_n)) {
440	res = orig_n;
441
442	if (orig_n / 16) {
443	orig_n = orig_n % 16;
444
445	__asm__ __volatile__(
446	" lsr lp_count, %7,4 \n"
447	" lp 3f \n"
448	" ld.ab %3, [%2, 4] \n"
449	" ld.ab %4, [%2, 4] \n"
450	" ld.ab %5, [%2, 4] \n"
451	" ld.ab %6, [%2, 4] \n"
452	"1: st.ab %3, [%1, 4] \n"
453	"11: st.ab %4, [%1, 4] \n"
454	"12: st.ab %5, [%1, 4] \n"
455	"13: st.ab %6, [%1, 4] \n"
456	" sub %0, %0, 16 \n"
457	"3:;nop \n"
458	" .section .fixup, \"ax\" \n"
459	" .align 4 \n"
460	"4: j 3b \n"
461	" .previous \n"
462	" .section __ex_table, \"a\" \n"
463	" .align 4 \n"
464	" .word 1b, 4b \n"
465	" .word 11b,4b \n"
466	" .word 12b,4b \n"
467	" .word 13b,4b \n"
468	" .previous \n"
469	: "+r" (res), "+r"(to), "+r"(from),
470	"=r"(tmp1), "=r"(tmp2), "=r"(tmp3), "=r"(tmp4)
471	: "ir"(n)
472	: "lp_count", "memory");
473	}
474	if (orig_n / 8) {
475	orig_n = orig_n % 8;
476
477	__asm__ __volatile__(
478	" ld.ab %3, [%2,4] \n"
479	" ld.ab %4, [%2,4] \n"
480	"14: st.ab %3, [%1,4] \n"
481	"15: st.ab %4, [%1,4] \n"
482	" sub %0, %0, 8 \n"
483	"31:;nop \n"
484	" .section .fixup, \"ax\" \n"
485	" .align 4 \n"
486	"4: j 31b \n"
487	" .previous \n"
488	" .section __ex_table, \"a\" \n"
489	" .align 4 \n"
490	" .word 14b,4b \n"
491	" .word 15b,4b \n"
492	" .previous \n"
493	: "+r" (res), "+r"(to), "+r"(from),
494	"=r"(tmp1), "=r"(tmp2)
495	:
496	: "memory");
497	}
498	if (orig_n / 4) {
499	orig_n = orig_n % 4;
500
501	__asm__ __volatile__(
502	" ld.ab %3, [%2,4] \n"
503	"16: st.ab %3, [%1,4] \n"
504	" sub %0, %0, 4 \n"
505	"32:;nop \n"
506	" .section .fixup, \"ax\" \n"
507	" .align 4 \n"
508	"4: j 32b \n"
509	" .previous \n"
510	" .section __ex_table, \"a\" \n"
511	" .align 4 \n"
512	" .word 16b,4b \n"
513	" .previous \n"
514	: "+r" (res), "+r"(to), "+r"(from), "=r"(tmp1)
515	:
516	: "memory");
517	}
518	if (orig_n / 2) {
519	orig_n = orig_n % 2;
520
521	__asm__ __volatile__(
522	" ldw.ab %3, [%2,2] \n"
523	"17: stw.ab %3, [%1,2] \n"
524	" sub %0, %0, 2 \n"
525	"33:;nop \n"
526	" .section .fixup, \"ax\" \n"
527	" .align 4 \n"
528	"4: j 33b \n"
529	" .previous \n"
530	" .section __ex_table, \"a\" \n"
531	" .align 4 \n"
532	" .word 17b,4b \n"
533	" .previous \n"
534	: "+r" (res), "+r"(to), "+r"(from), "=r"(tmp1)
535	:
536	: "memory");
537	}
538	if (orig_n & 1) {
539	__asm__ __volatile__(
540	" ldb.ab %3, [%2,1] \n"
541	"18: stb.ab %3, [%1,1] \n"
542	" sub %0, %0, 1 \n"
543	"34: ;nop \n"
544	" .section .fixup, \"ax\" \n"
545	" .align 4 \n"
546	"4: j 34b \n"
547	" .previous \n"
548	" .section __ex_table, \"a\" \n"
549	" .align 4 \n"
550	" .word 18b,4b \n"
551	" .previous \n"
552	: "+r" (res), "+r"(to), "+r"(from), "=r"(tmp1)
553	:
554	: "memory");
555	}
556	} else { /* n is NOT constant, so laddered copy of 16x,8,4,2,1 */
557
558	__asm__ __volatile__(
559	" mov %0,%3 \n"
560	" lsr.f lp_count, %3,4 \n" /* 16x bytes */
561	" lpnz 3f \n"
562	" ld.ab %5, [%2, 4] \n"
563	" ld.ab %6, [%2, 4] \n"
564	" ld.ab %7, [%2, 4] \n"
565	" ld.ab %8, [%2, 4] \n"
566	"1: st.ab %5, [%1, 4] \n"
567	"11: st.ab %6, [%1, 4] \n"
568	"12: st.ab %7, [%1, 4] \n"
569	"13: st.ab %8, [%1, 4] \n"
570	" sub %0, %0, 16 \n"
571	"3: and.f %3,%3,0xf \n" /* stragglers */
572	" bz 34f \n"
573	" bbit0 %3,3,31f \n" /* 8 bytes left */
574	" ld.ab %5, [%2,4] \n"
575	" ld.ab %6, [%2,4] \n"
576	"14: st.ab %5, [%1,4] \n"
577	"15: st.ab %6, [%1,4] \n"
578	" sub.f %0, %0, 8 \n"
579	"31: bbit0 %3,2,32f \n" /* 4 bytes left */
580	" ld.ab %5, [%2,4] \n"
581	"16: st.ab %5, [%1,4] \n"
582	" sub.f %0, %0, 4 \n"
583	"32: bbit0 %3,1,33f \n" /* 2 bytes left */
584	" ldw.ab %5, [%2,2] \n"
585	"17: stw.ab %5, [%1,2] \n"
586	" sub.f %0, %0, 2 \n"
587	"33: bbit0 %3,0,34f \n"
588	" ldb.ab %5, [%2,1] \n" /* 1 byte left */
589	"18: stb.ab %5, [%1,1] \n"
590	" sub.f %0, %0, 1 \n"
591	"34: ;nop \n"
592	" .section .fixup, \"ax\" \n"
593	" .align 4 \n"
594	"4: j 34b \n"
595	" .previous \n"
596	" .section __ex_table, \"a\" \n"
597	" .align 4 \n"
598	" .word 1b, 4b \n"
599	" .word 11b,4b \n"
600	" .word 12b,4b \n"
601	" .word 13b,4b \n"
602	" .word 14b,4b \n"
603	" .word 15b,4b \n"
604	" .word 16b,4b \n"
605	" .word 17b,4b \n"
606	" .word 18b,4b \n"
607	" .previous \n"
608	: "=r" (res), "+r"(to), "+r"(from), "+r"(n), "=r"(val),
609	"=r"(tmp1), "=r"(tmp2), "=r"(tmp3), "=r"(tmp4)
610	:
611	: "lp_count", "memory");
612	}
613
614	return res;
615	}
616
617	static inline unsigned long __arc_clear_user(void __user *to, unsigned long n)
618	{
619	long res = n;
620	unsigned char *d_char = to;
621
622	__asm__ __volatile__(
623	" bbit0 %0, 0, 1f \n"
624	"75: stb.ab %2, [%0,1] \n"
625	" sub %1, %1, 1 \n"
626	"1: bbit0 %0, 1, 2f \n"
627	"76: stw.ab %2, [%0,2] \n"
628	" sub %1, %1, 2 \n"
629	"2: asr.f lp_count, %1, 2 \n"
630	" lpnz 3f \n"
631	"77: st.ab %2, [%0,4] \n"
632	" sub %1, %1, 4 \n"
633	"3: bbit0 %1, 1, 4f \n"
634	"78: stw.ab %2, [%0,2] \n"
635	" sub %1, %1, 2 \n"
636	"4: bbit0 %1, 0, 5f \n"
637	"79: stb.ab %2, [%0,1] \n"
638	" sub %1, %1, 1 \n"
639	"5: \n"
640	" .section .fixup, \"ax\" \n"
641	" .align 4 \n"
642	"3: j 5b \n"
643	" .previous \n"
644	" .section __ex_table, \"a\" \n"
645	" .align 4 \n"
646	" .word 75b, 3b \n"
647	" .word 76b, 3b \n"
648	" .word 77b, 3b \n"
649	" .word 78b, 3b \n"
650	" .word 79b, 3b \n"
651	" .previous \n"
652	: "+r"(d_char), "+r"(res)
653	: "i"(0)
654	: "lp_count", "lp_start", "lp_end", "memory");
655
656	return res;
657	}
658
659	static inline long
660	__arc_strncpy_from_user(char dst, const char __user src, long count)
661	{
8922bc30	662	long res = 0;
43697cb0	663	char val;
43697cb0 VG	664
	665	if (count == 0)
	666	return 0;
	667
	668	__asm__ __volatile__(
8922bc30	669	" lp 3f \n"
43697cb0	670	"1: ldb.ab %3, [%2, 1] \n"
8922bc30	671	" breq.d %3, 0, 3f \n"
43697cb0	672	" stb.ab %3, [%1, 1] \n"
8922bc30 VG	673	" add %0, %0, 1 # Num of NON NULL bytes copied \n"
8922bc30 VG	674	"3: \n"
43697cb0 VG	675	" .section .fixup, \"ax\" \n"
43697cb0 VG	676	" .align 4 \n"
8922bc30	677	"4: mov %0, %4 # sets @res as -EFAULT \n"
43697cb0 VG	678	" j 3b \n"
	679	" .previous \n"
	680	" .section __ex_table, \"a\" \n"
	681	" .align 4 \n"
	682	" .word 1b, 4b \n"
	683	" .previous \n"
8922bc30 VG	684	: "+r"(res), "+r"(dst), "+r"(src), "=r"(val)
8922bc30 VG	685	: "g"(-EFAULT), "l"(count)
43697cb0 VG	686	: "memory");
	687
	688	return res;
	689	}
	690
	691	static inline long __arc_strnlen_user(const char __user *s, long n)
	692	{
	693	long res, tmp1, cnt;
	694	char val;
	695
	696	__asm__ __volatile__(
	697	" mov %2, %1 \n"
	698	"1: ldb.ab %3, [%0, 1] \n"
	699	" breq.d %3, 0, 2f \n"
	700	" sub.f %2, %2, 1 \n"
	701	" bnz 1b \n"
	702	" sub %2, %2, 1 \n"
	703	"2: sub %0, %1, %2 \n"
	704	"3: ;nop \n"
	705	" .section .fixup, \"ax\" \n"
	706	" .align 4 \n"
	707	"4: mov %0, 0 \n"
	708	" j 3b \n"
	709	" .previous \n"
	710	" .section __ex_table, \"a\" \n"
	711	" .align 4 \n"
	712	" .word 1b, 4b \n"
	713	" .previous \n"
	714	: "=r"(res), "=r"(tmp1), "=r"(cnt), "=r"(val)
	715	: "0"(s), "1"(n)
	716	: "memory");
	717
	718	return res;
	719	}
	720
	721	#ifndef CONFIG_CC_OPTIMIZE_FOR_SIZE
	722	#define __copy_from_user(t, f, n) __arc_copy_from_user(t, f, n)
	723	#define __copy_to_user(t, f, n) __arc_copy_to_user(t, f, n)
	724	#define __clear_user(d, n) __arc_clear_user(d, n)
	725	#define __strncpy_from_user(d, s, n) __arc_strncpy_from_user(d, s, n)
	726	#define __strnlen_user(s, n) __arc_strnlen_user(s, n)
	727	#else
	728	extern long arc_copy_from_user_noinline(void to, const void __user from,
	729	unsigned long n);
	730	extern long arc_copy_to_user_noinline(void __user to, const void from,
	731	unsigned long n);
	732	extern unsigned long arc_clear_user_noinline(void __user *to,
	733	unsigned long n);
	734	extern long arc_strncpy_from_user_noinline (char dst, const char __user src,
	735	long count);
	736	extern long arc_strnlen_user_noinline(const char __user *src, long n);
	737
	738	#define __copy_from_user(t, f, n) arc_copy_from_user_noinline(t, f, n)
	739	#define __copy_to_user(t, f, n) arc_copy_to_user_noinline(t, f, n)
	740	#define __clear_user(d, n) arc_clear_user_noinline(d, n)
	741	#define __strncpy_from_user(d, s, n) arc_strncpy_from_user_noinline(d, s, n)
	742	#define __strnlen_user(s, n) arc_strnlen_user_noinline(s, n)
	743
	744	#endif
	745
	746	#include <asm-generic/uaccess.h>
	747
	748	extern int fixup_exception(struct pt_regs *regs);
	749
750	#endif