[linux-2.6-block.git] / arch / nios2 / include / asm / uaccess.h

/*
 * User space memory access functions for Nios II
 *
 * Copyright (C) 2010-2011, Tobias Klauser <tklauser@distanz.ch>
 * Copyright (C) 2009, Wind River Systems Inc
 *   Implemented by fredrik.markstrom@gmail.com and ivarholmqvist@gmail.com
 *
 * This file is subject to the terms and conditions of the GNU General Public
 * License.  See the file "COPYING" in the main directory of this archive
 * for more details.
 */

#ifndef _ASM_NIOS2_UACCESS_H
#define _ASM_NIOS2_UACCESS_H

#include <linux/string.h>

#include <asm/page.h>

#include <asm/extable.h>
#include <asm-generic/access_ok.h>

# define __EX_TABLE_SECTION	".section __ex_table,\"a\"\n"

/*
 * Zero Userspace
 */

static inline unsigned long __must_check __clear_user(void __user *to,
						      unsigned long n)
{
	__asm__ __volatile__ (
		"1:     stb     zero, 0(%1)\n"
		"       addi    %0, %0, -1\n"
		"       addi    %1, %1, 1\n"
		"       bne     %0, zero, 1b\n"
		"2:\n"
		__EX_TABLE_SECTION
		".word  1b, 2b\n"
		".previous\n"
		: "=r" (n), "=r" (to)
		: "0" (n), "1" (to)
	);

	return n;
}

static inline unsigned long __must_check clear_user(void __user *to,
						    unsigned long n)
{
	if (!access_ok(to, n))
		return n;
	return __clear_user(to, n);
}

extern unsigned long
raw_copy_from_user(void *to, const void __user *from, unsigned long n);
extern unsigned long
raw_copy_to_user(void __user *to, const void *from, unsigned long n);
#define INLINE_COPY_FROM_USER
#define INLINE_COPY_TO_USER

extern long strncpy_from_user(char *__to, const char __user *__from,
			      long __len);
extern __must_check long strnlen_user(const char __user *s, long n);

/* Optimized macros */
#define __get_user_asm(val, insn, addr, err)				\
{									\
	unsigned long __gu_val;						\
	__asm__ __volatile__(						\
	"       movi    %0, %3\n"					\
	"1:   " insn " %1, 0(%2)\n"					\
	"       movi     %0, 0\n"					\
	"2:\n"								\
	"       .section __ex_table,\"a\"\n"				\
	"       .word 1b, 2b\n"						\
	"       .previous"						\
	: "=&r" (err), "=r" (__gu_val)					\
	: "r" (addr), "i" (-EFAULT));					\
	val = (__force __typeof__(*(addr)))__gu_val;			\
}

extern void __get_user_unknown(void);

#define __get_user_8(val, ptr, err) do {				\
	u64 __val = 0;							\
	err = 0;							\
	if (raw_copy_from_user(&(__val), ptr, sizeof(val))) {		\
		err = -EFAULT;						\
	} else {							\
		val = (typeof(val))(typeof((val) - (val)))__val;	\
	}								\
	} while (0)

#define __get_user_common(val, size, ptr, err)				\
do {									\
	switch (size) {							\
	case 1:								\
		__get_user_asm(val, "ldbu", ptr, err);			\
		break;							\
	case 2:								\
		__get_user_asm(val, "ldhu", ptr, err);			\
		break;							\
	case 4:								\
		__get_user_asm(val, "ldw", ptr, err);			\
		break;							\
	case 8:								\
		__get_user_8(val, ptr, err);				\
		break;							\
	default:							\
		__get_user_unknown();					\
		break;							\
	}								\
} while (0)

#define __get_user(x, ptr)						\
	({								\
	long __gu_err = -EFAULT;					\
	const __typeof__(*(ptr)) __user *__gu_ptr = (ptr);		\
	__get_user_common(x, sizeof(*(ptr)), __gu_ptr, __gu_err);	\
	__gu_err;							\
	})

#define get_user(x, ptr)						\
({									\
	long __gu_err = -EFAULT;					\
	const __typeof__(*(ptr)) __user *__gu_ptr = (ptr);		\
	if (access_ok( __gu_ptr, sizeof(*__gu_ptr)))	\
		__get_user_common(x, sizeof(*__gu_ptr),			\
			__gu_ptr, __gu_err);				\
	__gu_err;							\
})

#define __put_user_asm(val, insn, ptr, err)				\
{									\
	__asm__ __volatile__(						\
	"       movi    %0, %3\n"					\
	"1:   " insn " %1, 0(%2)\n"					\
	"       movi     %0, 0\n"					\
	"2:\n"								\
	"       .section __ex_table,\"a\"\n"				\
	"       .word 1b, 2b\n"						\
	"       .previous\n"						\
	: "=&r" (err)							\
	: "r" (val), "r" (ptr), "i" (-EFAULT));				\
}

#define __put_user_common(__pu_val, __pu_ptr)				\
({									\
	long __pu_err = -EFAULT;					\
	switch (sizeof(*__pu_ptr)) {					\
	case 1:								\
		__put_user_asm(__pu_val, "stb", __pu_ptr, __pu_err);	\
		break;							\
	case 2:								\
		__put_user_asm(__pu_val, "sth", __pu_ptr, __pu_err);	\
		break;							\
	case 4:								\
		__put_user_asm(__pu_val, "stw", __pu_ptr, __pu_err);	\
		break;							\
	default:							\
		/* XXX: This looks wrong... */				\
		__pu_err = 0;						\
		if (__copy_to_user(__pu_ptr, &(__pu_val),		\
			sizeof(*__pu_ptr)))				\
			__pu_err = -EFAULT;				\
		break;							\
	}								\
	__pu_err;							\
})

#define __put_user(x, ptr)						\
({									\
	__auto_type __pu_ptr = (ptr);					\
	typeof(*__pu_ptr) __pu_val = (typeof(*__pu_ptr))(x);		\
	__put_user_common(__pu_val, __pu_ptr);				\
})

#define put_user(x, ptr)						\
({									\
	__auto_type __pu_ptr = (ptr);					\
	typeof(*__pu_ptr) __pu_val = (typeof(*__pu_ptr))(x);		\
	access_ok(__pu_ptr, sizeof(*__pu_ptr)) ?			\
		__put_user_common(__pu_val, __pu_ptr) :			\
		-EFAULT;						\
})

#endif /* _ASM_NIOS2_UACCESS_H */
Commit	Line	Data
5ccc6af5 LFT	1	/*
	2	* User space memory access functions for Nios II
	3	*
	4	* Copyright (C) 2010-2011, Tobias Klauser <tklauser@distanz.ch>
	5	* Copyright (C) 2009, Wind River Systems Inc
	6	* Implemented by fredrik.markstrom@gmail.com and ivarholmqvist@gmail.com
	7	*
	8	* This file is subject to the terms and conditions of the GNU General Public
	9	* License. See the file "COPYING" in the main directory of this archive
	10	* for more details.
	11	*/
	12
	13	#ifndef _ASM_NIOS2_UACCESS_H
	14	#define _ASM_NIOS2_UACCESS_H
	15
5ccc6af5 LFT	16	#include <linux/string.h>
	17
	18	#include <asm/page.h>
	19
981db65b	20	#include <asm/extable.h>
12700c17	21	#include <asm-generic/access_ok.h>
5ccc6af5 LFT	22
	23	# define __EX_TABLE_SECTION ".section __ex_table,\"a\"\n"
	24
	25	/*
	26	* Zero Userspace
	27	*/
	28
	29	static inline unsigned long __must_check __clear_user(void __user *to,
	30	unsigned long n)
	31	{
	32	__asm__ __volatile__ (
	33	"1: stb zero, 0(%1)\n"
	34	" addi %0, %0, -1\n"
	35	" addi %1, %1, 1\n"
	36	" bne %0, zero, 1b\n"
	37	"2:\n"
	38	__EX_TABLE_SECTION
	39	".word 1b, 2b\n"
	40	".previous\n"
	41	: "=r" (n), "=r" (to)
	42	: "0" (n), "1" (to)
	43	);
	44
	45	return n;
	46	}
	47
	48	static inline unsigned long __must_check clear_user(void __user *to,
	49	unsigned long n)
	50	{
96d4f267	51	if (!access_ok(to, n))
5ccc6af5 LFT	52	return n;
	53	return __clear_user(to, n);
	54	}
	55
de51d6cc AV	56	extern unsigned long
	57	raw_copy_from_user(void to, const void __user from, unsigned long n);
	58	extern unsigned long
	59	raw_copy_to_user(void __user to, const void from, unsigned long n);
	60	#define INLINE_COPY_FROM_USER
	61	#define INLINE_COPY_TO_USER
5ccc6af5 LFT	62
5ccc6af5 LFT	63	extern long strncpy_from_user(char __to, const char __user __from,
7f1e6141	64	long __len);
7f1e6141	65	extern __must_check long strnlen_user(const char __user *s, long n);
5ccc6af5	66
5ccc6af5 LFT	67	/* Optimized macros */
	68	#define __get_user_asm(val, insn, addr, err) \
	69	{ \
a97b693c	70	unsigned long __gu_val; \
5ccc6af5 LFT	71	__asm__ __volatile__( \
	72	" movi %0, %3\n" \
	73	"1: " insn " %1, 0(%2)\n" \
	74	" movi %0, 0\n" \
	75	"2:\n" \
	76	" .section __ex_table,\"a\"\n" \
	77	" .word 1b, 2b\n" \
	78	" .previous" \
a97b693c	79	: "=&r" (err), "=r" (__gu_val) \
5ccc6af5	80	: "r" (addr), "i" (-EFAULT)); \
a97b693c	81	val = (__force __typeof__(*(addr)))__gu_val; \
5ccc6af5 LFT	82	}
5ccc6af5 LFT	83
a97b693c AB	84	extern void __get_user_unknown(void);
	85
	86	#define __get_user_8(val, ptr, err) do { \
	87	u64 __val = 0; \
5ccc6af5	88	err = 0; \
a97b693c	89	if (raw_copy_from_user(&(__val), ptr, sizeof(val))) { \
5ccc6af5	90	err = -EFAULT; \
a97b693c AB	91	} else { \
a97b693c AB	92	val = (typeof(val))(typeof((val) - (val)))__val; \
5ccc6af5 LFT	93	} \
	94	} while (0)
	95
	96	#define __get_user_common(val, size, ptr, err) \
	97	do { \
	98	switch (size) { \
	99	case 1: \
	100	__get_user_asm(val, "ldbu", ptr, err); \
	101	break; \
	102	case 2: \
	103	__get_user_asm(val, "ldhu", ptr, err); \
	104	break; \
	105	case 4: \
	106	__get_user_asm(val, "ldw", ptr, err); \
	107	break; \
a97b693c AB	108	case 8: \
	109	__get_user_8(val, ptr, err); \
	110	break; \
5ccc6af5	111	default: \
a97b693c	112	__get_user_unknown(); \
5ccc6af5 LFT	113	break; \
	114	} \
	115	} while (0)
	116
	117	#define __get_user(x, ptr) \
	118	({ \
	119	long __gu_err = -EFAULT; \
	120	const __typeof__((ptr)) __user __gu_ptr = (ptr); \
a97b693c	121	__get_user_common(x, sizeof(*(ptr)), __gu_ptr, __gu_err); \
5ccc6af5 LFT	122	__gu_err; \
	123	})
	124
	125	#define get_user(x, ptr) \
	126	({ \
	127	long __gu_err = -EFAULT; \
	128	const __typeof__((ptr)) __user __gu_ptr = (ptr); \
96d4f267	129	if (access_ok( __gu_ptr, sizeof(*__gu_ptr))) \
a97b693c	130	__get_user_common(x, sizeof(*__gu_ptr), \
5ccc6af5	131	__gu_ptr, __gu_err); \
5ccc6af5 LFT	132	__gu_err; \
	133	})
	134
	135	#define __put_user_asm(val, insn, ptr, err) \
	136	{ \
	137	__asm__ __volatile__( \
	138	" movi %0, %3\n" \
	139	"1: " insn " %1, 0(%2)\n" \
	140	" movi %0, 0\n" \
	141	"2:\n" \
	142	" .section __ex_table,\"a\"\n" \
	143	" .word 1b, 2b\n" \
	144	" .previous\n" \
	145	: "=&r" (err) \
	146	: "r" (val), "r" (ptr), "i" (-EFAULT)); \
	147	}
	148
90997c12	149	#define __put_user_common(__pu_val, __pu_ptr) \
5ccc6af5 LFT	150	({ \
5ccc6af5 LFT	151	long __pu_err = -EFAULT; \
90997c12 AB	152	switch (sizeof(*__pu_ptr)) { \
	153	case 1: \
	154	__put_user_asm(__pu_val, "stb", __pu_ptr, __pu_err); \
	155	break; \
	156	case 2: \
	157	__put_user_asm(__pu_val, "sth", __pu_ptr, __pu_err); \
	158	break; \
	159	case 4: \
	160	__put_user_asm(__pu_val, "stw", __pu_ptr, __pu_err); \
	161	break; \
	162	default: \
	163	/* XXX: This looks wrong... */ \
	164	__pu_err = 0; \
	165	if (__copy_to_user(__pu_ptr, &(__pu_val), \
	166	sizeof(*__pu_ptr))) \
	167	__pu_err = -EFAULT; \
	168	break; \
5ccc6af5 LFT	169	} \
	170	__pu_err; \
	171	})
	172
90997c12 AB	173	#define __put_user(x, ptr) \
	174	({ \
	175	__auto_type __pu_ptr = (ptr); \
	176	typeof(__pu_ptr) __pu_val = (typeof(__pu_ptr))(x); \
	177	__put_user_common(__pu_val, __pu_ptr); \
	178	})
	179
	180	#define put_user(x, ptr) \
	181	({ \
	182	__auto_type __pu_ptr = (ptr); \
	183	typeof(__pu_ptr) __pu_val = (typeof(__pu_ptr))(x); \
	184	access_ok(__pu_ptr, sizeof(*__pu_ptr)) ? \
	185	__put_user_common(__pu_val, __pu_ptr) : \
	186	-EFAULT; \
	187	})
5ccc6af5 LFT	188
5ccc6af5 LFT	189	#endif /* _ASM_NIOS2_UACCESS_H */