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

/* SPDX-License-Identifier: GPL-2.0-or-later */
/*
 * OpenRISC Linux
 *
 * Linux architectural port borrowing liberally from similar works of
 * others.  All original copyrights apply as per the original source
 * declaration.
 *
 * OpenRISC implementation:
 * Copyright (C) 2003 Matjaz Breskvar <phoenix@bsemi.com>
 * Copyright (C) 2010-2011 Jonas Bonn <jonas@southpole.se>
 * et al.
 */

#ifndef __ASM_OPENRISC_UACCESS_H
#define __ASM_OPENRISC_UACCESS_H

/*
 * User space memory access functions
 */
#include <linux/prefetch.h>
#include <linux/string.h>
#include <asm/page.h>
#include <asm/extable.h>
#include <asm-generic/access_ok.h>

/*
 * These are the main single-value transfer routines.  They automatically
 * use the right size if we just have the right pointer type.
 *
 * This gets kind of ugly. We want to return _two_ values in "get_user()"
 * and yet we don't want to do any pointers, because that is too much
 * of a performance impact. Thus we have a few rather ugly macros here,
 * and hide all the uglyness from the user.
 *
 * The "__xxx" versions of the user access functions are versions that
 * do not verify the address space, that must have been done previously
 * with a separate "access_ok()" call (this is used when we do multiple
 * accesses to the same area of user memory).
 *
 * As we use the same address space for kernel and user data on the
 * PowerPC, we can just do these as direct assignments.  (Of course, the
 * exception handling means that it's no longer "just"...)
 */
#define get_user(x, ptr) \
	__get_user_check((x), (ptr), sizeof(*(ptr)))
#define put_user(x, ptr) \
	__put_user_check((__typeof__(*(ptr)))(x), (ptr), sizeof(*(ptr)))

#define __get_user(x, ptr) \
	__get_user_nocheck((x), (ptr), sizeof(*(ptr)))
#define __put_user(x, ptr) \
	__put_user_nocheck((__typeof__(*(ptr)))(x), (ptr), sizeof(*(ptr)))

extern long __put_user_bad(void);

#define __put_user_nocheck(x, ptr, size)		\
({							\
	long __pu_err;					\
	__put_user_size((x), (ptr), (size), __pu_err);	\
	__pu_err;					\
})

#define __put_user_check(x, ptr, size)					\
({									\
	long __pu_err = -EFAULT;					\
	__typeof__(*(ptr)) __user *__pu_addr = (ptr);			\
	if (access_ok(__pu_addr, size))			\
		__put_user_size((x), __pu_addr, (size), __pu_err);	\
	__pu_err;							\
})

#define __put_user_size(x, ptr, size, retval)				\
do {									\
	retval = 0;							\
	switch (size) {							\
	case 1: __put_user_asm(x, ptr, retval, "l.sb"); break;		\
	case 2: __put_user_asm(x, ptr, retval, "l.sh"); break;		\
	case 4: __put_user_asm(x, ptr, retval, "l.sw"); break;		\
	case 8: __put_user_asm2(x, ptr, retval); break;			\
	default: __put_user_bad();					\
	}								\
} while (0)

struct __large_struct {
	unsigned long buf[100];
};
#define __m(x) (*(struct __large_struct *)(x))

/*
 * We don't tell gcc that we are accessing memory, but this is OK
 * because we do not write to any memory gcc knows about, so there
 * are no aliasing issues.
 */
#define __put_user_asm(x, addr, err, op)			\
	__asm__ __volatile__(					\
		"1:	"op" 0(%2),%1\n"			\
		"2:\n"						\
		".section .fixup,\"ax\"\n"			\
		"3:	l.addi %0,r0,%3\n"			\
		"	l.j 2b\n"				\
		"	l.nop\n"				\
		".previous\n"					\
		".section __ex_table,\"a\"\n"			\
		"	.align 2\n"				\
		"	.long 1b,3b\n"				\
		".previous"					\
		: "=r"(err)					\
		: "r"(x), "r"(addr), "i"(-EFAULT), "0"(err))

#define __put_user_asm2(x, addr, err)				\
	__asm__ __volatile__(					\
		"1:	l.sw 0(%2),%1\n"			\
		"2:	l.sw 4(%2),%H1\n"			\
		"3:\n"						\
		".section .fixup,\"ax\"\n"			\
		"4:	l.addi %0,r0,%3\n"			\
		"	l.j 3b\n"				\
		"	l.nop\n"				\
		".previous\n"					\
		".section __ex_table,\"a\"\n"			\
		"	.align 2\n"				\
		"	.long 1b,4b\n"				\
		"	.long 2b,4b\n"				\
		".previous"					\
		: "=r"(err)					\
		: "r"(x), "r"(addr), "i"(-EFAULT), "0"(err))

#define __get_user_nocheck(x, ptr, size)			\
({								\
	long __gu_err;						\
	__get_user_size((x), (ptr), (size), __gu_err);		\
	__gu_err;						\
})

#define __get_user_check(x, ptr, size)					\
({									\
	long __gu_err = -EFAULT;					\
	const __typeof__(*(ptr)) __user *__gu_addr = (ptr);		\
	if (access_ok(__gu_addr, size))					\
		__get_user_size((x), __gu_addr, (size), __gu_err);	\
	else								\
		(x) = (__typeof__(*(ptr))) 0;				\
	__gu_err;							\
})

extern long __get_user_bad(void);

#define __get_user_size(x, ptr, size, retval)				\
do {									\
	retval = 0;							\
	switch (size) {							\
	case 1: __get_user_asm(x, ptr, retval, "l.lbz"); break;		\
	case 2: __get_user_asm(x, ptr, retval, "l.lhz"); break;		\
	case 4: __get_user_asm(x, ptr, retval, "l.lwz"); break;		\
	case 8: __get_user_asm2(x, ptr, retval); break;			\
	default: (x) = (__typeof__(*(ptr)))__get_user_bad();		\
	}								\
} while (0)

#define __get_user_asm(x, addr, err, op)		\
{							\
	unsigned long __gu_tmp;				\
	__asm__ __volatile__(				\
		"1:	"op" %1,0(%2)\n"		\
		"2:\n"					\
		".section .fixup,\"ax\"\n"		\
		"3:	l.addi %0,r0,%3\n"		\
		"	l.addi %1,r0,0\n"		\
		"	l.j 2b\n"			\
		"	l.nop\n"			\
		".previous\n"				\
		".section __ex_table,\"a\"\n"		\
		"	.align 2\n"			\
		"	.long 1b,3b\n"			\
		".previous"				\
		: "=r"(err), "=r"(__gu_tmp)		\
		: "r"(addr), "i"(-EFAULT), "0"(err));	\
	(x) = (__typeof__(*(addr)))__gu_tmp;		\
}

#define __get_user_asm2(x, addr, err)			\
{							\
	unsigned long long __gu_tmp;			\
	__asm__ __volatile__(				\
		"1:	l.lwz %1,0(%2)\n"		\
		"2:	l.lwz %H1,4(%2)\n"		\
		"3:\n"					\
		".section .fixup,\"ax\"\n"		\
		"4:	l.addi %0,r0,%3\n"		\
		"	l.addi %1,r0,0\n"		\
		"	l.addi %H1,r0,0\n"		\
		"	l.j 3b\n"			\
		"	l.nop\n"			\
		".previous\n"				\
		".section __ex_table,\"a\"\n"		\
		"	.align 2\n"			\
		"	.long 1b,4b\n"			\
		"	.long 2b,4b\n"			\
		".previous"				\
		: "=r"(err), "=&r"(__gu_tmp)		\
		: "r"(addr), "i"(-EFAULT), "0"(err));	\
	(x) = (__typeof__(*(addr)))(			\
		(__typeof__((x)-(x)))__gu_tmp);		\
}

/* more complex routines */

extern unsigned long __must_check
__copy_tofrom_user(void *to, const void *from, unsigned long size);
static inline unsigned long
raw_copy_from_user(void *to, const void __user *from, unsigned long size)
{
	return __copy_tofrom_user(to, (__force const void *)from, size);
}
static inline unsigned long
raw_copy_to_user(void __user *to, const void *from, unsigned long size)
{
	return __copy_tofrom_user((__force void *)to, from, size);
}
#define INLINE_COPY_FROM_USER
#define INLINE_COPY_TO_USER

extern unsigned long __clear_user(void __user *addr, unsigned long size);

static inline __must_check unsigned long
clear_user(void __user *addr, unsigned long size)
{
	if (likely(access_ok(addr, size)))
		size = __clear_user(addr, size);
	return size;
}

extern long strncpy_from_user(char *dest, const char __user *src, long count);

extern __must_check long strnlen_user(const char __user *str, long n);

#endif /* __ASM_OPENRISC_UACCESS_H */
Commit	Line	Data
2874c5fd	1	/* SPDX-License-Identifier: GPL-2.0-or-later */
61e85e36 JB	2	/*
	3	* OpenRISC Linux
	4	*
	5	* Linux architectural port borrowing liberally from similar works of
	6	* others. All original copyrights apply as per the original source
	7	* declaration.
	8	*
	9	* OpenRISC implementation:
	10	* Copyright (C) 2003 Matjaz Breskvar <phoenix@bsemi.com>
	11	* Copyright (C) 2010-2011 Jonas Bonn <jonas@southpole.se>
	12	* et al.
61e85e36 JB	13	*/
	14
	15	#ifndef __ASM_OPENRISC_UACCESS_H
	16	#define __ASM_OPENRISC_UACCESS_H
	17
	18	/*
	19	* User space memory access functions
	20	*/
61e85e36 JB	21	#include <linux/prefetch.h>
61e85e36 JB	22	#include <linux/string.h>
61e85e36	23	#include <asm/page.h>
6c36a4eb	24	#include <asm/extable.h>
12700c17	25	#include <asm-generic/access_ok.h>
61e85e36	26
61e85e36 JB	27	/*
	28	* These are the main single-value transfer routines. They automatically
	29	* use the right size if we just have the right pointer type.
	30	*
	31	* This gets kind of ugly. We want to return _two_ values in "get_user()"
	32	* and yet we don't want to do any pointers, because that is too much
	33	* of a performance impact. Thus we have a few rather ugly macros here,
	34	* and hide all the uglyness from the user.
	35	*
	36	* The "__xxx" versions of the user access functions are versions that
	37	* do not verify the address space, that must have been done previously
	38	* with a separate "access_ok()" call (this is used when we do multiple
	39	* accesses to the same area of user memory).
	40	*
	41	* As we use the same address space for kernel and user data on the
	42	* PowerPC, we can just do these as direct assignments. (Of course, the
	43	* exception handling means that it's no longer "just"...)
	44	*/
	45	#define get_user(x, ptr) \
	46	__get_user_check((x), (ptr), sizeof(*(ptr)))
	47	#define put_user(x, ptr) \
	48	__put_user_check((__typeof__((ptr)))(x), (ptr), sizeof((ptr)))
	49
	50	#define __get_user(x, ptr) \
	51	__get_user_nocheck((x), (ptr), sizeof(*(ptr)))
	52	#define __put_user(x, ptr) \
	53	__put_user_nocheck((__typeof__((ptr)))(x), (ptr), sizeof((ptr)))
	54
	55	extern long __put_user_bad(void);
	56
	57	#define __put_user_nocheck(x, ptr, size) \
	58	({ \
	59	long __pu_err; \
	60	__put_user_size((x), (ptr), (size), __pu_err); \
	61	__pu_err; \
	62	})
	63
	64	#define __put_user_check(x, ptr, size) \
	65	({ \
	66	long __pu_err = -EFAULT; \
17fcd83c	67	__typeof__((ptr)) __user __pu_addr = (ptr); \
96d4f267	68	if (access_ok(__pu_addr, size)) \
61e85e36 JB	69	__put_user_size((x), __pu_addr, (size), __pu_err); \
	70	__pu_err; \
	71	})
	72
	73	#define __put_user_size(x, ptr, size, retval) \
	74	do { \
	75	retval = 0; \
	76	switch (size) { \
	77	case 1: __put_user_asm(x, ptr, retval, "l.sb"); break; \
	78	case 2: __put_user_asm(x, ptr, retval, "l.sh"); break; \
	79	case 4: __put_user_asm(x, ptr, retval, "l.sw"); break; \
	80	case 8: __put_user_asm2(x, ptr, retval); break; \
	81	default: __put_user_bad(); \
	82	} \
	83	} while (0)
	84
	85	struct __large_struct {
	86	unsigned long buf[100];
	87	};
	88	#define __m(x) ((struct __large_struct )(x))
	89
	90	/*
	91	* We don't tell gcc that we are accessing memory, but this is OK
	92	* because we do not write to any memory gcc knows about, so there
	93	* are no aliasing issues.
	94	*/
	95	#define __put_user_asm(x, addr, err, op) \
	96	__asm__ __volatile__( \
	97	"1: "op" 0(%2),%1\n" \
	98	"2:\n" \
	99	".section .fixup,\"ax\"\n" \
	100	"3: l.addi %0,r0,%3\n" \
	101	" l.j 2b\n" \
	102	" l.nop\n" \
	103	".previous\n" \
	104	".section __ex_table,\"a\"\n" \
	105	" .align 2\n" \
	106	" .long 1b,3b\n" \
	107	".previous" \
	108	: "=r"(err) \
	109	: "r"(x), "r"(addr), "i"(-EFAULT), "0"(err))
	110
	111	#define __put_user_asm2(x, addr, err) \
	112	__asm__ __volatile__( \
	113	"1: l.sw 0(%2),%1\n" \
	114	"2: l.sw 4(%2),%H1\n" \
	115	"3:\n" \
	116	".section .fixup,\"ax\"\n" \
	117	"4: l.addi %0,r0,%3\n" \
	118	" l.j 3b\n" \
	119	" l.nop\n" \
	120	".previous\n" \
	121	".section __ex_table,\"a\"\n" \
	122	" .align 2\n" \
	123	" .long 1b,4b\n" \
	124	" .long 2b,4b\n" \
	125	".previous" \
	126	: "=r"(err) \
	127	: "r"(x), "r"(addr), "i"(-EFAULT), "0"(err))
	128
	129	#define __get_user_nocheck(x, ptr, size) \
	130	({ \
d877322b SH	131	long __gu_err; \
d877322b SH	132	__get_user_size((x), (ptr), (size), __gu_err); \
61e85e36 JB	133	__gu_err; \
	134	})
	135
	136	#define __get_user_check(x, ptr, size) \
	137	({ \
d877322b	138	long __gu_err = -EFAULT; \
17fcd83c	139	const __typeof__((ptr)) __user __gu_addr = (ptr); \
d877322b SH	140	if (access_ok(__gu_addr, size)) \
	141	__get_user_size((x), __gu_addr, (size), __gu_err); \
	142	else \
	143	(x) = (__typeof__(*(ptr))) 0; \
61e85e36 JB	144	__gu_err; \
	145	})
	146
	147	extern long __get_user_bad(void);
	148
	149	#define __get_user_size(x, ptr, size, retval) \
	150	do { \
	151	retval = 0; \
	152	switch (size) { \
	153	case 1: __get_user_asm(x, ptr, retval, "l.lbz"); break; \
	154	case 2: __get_user_asm(x, ptr, retval, "l.lhz"); break; \
	155	case 4: __get_user_asm(x, ptr, retval, "l.lwz"); break; \
154e67cd	156	case 8: __get_user_asm2(x, ptr, retval); break; \
d877322b	157	default: (x) = (__typeof__(*(ptr)))__get_user_bad(); \
61e85e36 JB	158	} \
	159	} while (0)
	160
	161	#define __get_user_asm(x, addr, err, op) \
d877322b SH	162	{ \
d877322b SH	163	unsigned long __gu_tmp; \
61e85e36 JB	164	__asm__ __volatile__( \
	165	"1: "op" %1,0(%2)\n" \
	166	"2:\n" \
	167	".section .fixup,\"ax\"\n" \
	168	"3: l.addi %0,r0,%3\n" \
	169	" l.addi %1,r0,0\n" \
	170	" l.j 2b\n" \
	171	" l.nop\n" \
	172	".previous\n" \
	173	".section __ex_table,\"a\"\n" \
	174	" .align 2\n" \
	175	" .long 1b,3b\n" \
	176	".previous" \
d877322b SH	177	: "=r"(err), "=r"(__gu_tmp) \
	178	: "r"(addr), "i"(-EFAULT), "0"(err)); \
	179	(x) = (__typeof__(*(addr)))__gu_tmp; \
	180	}
61e85e36 JB	181
61e85e36 JB	182	#define __get_user_asm2(x, addr, err) \
d877322b SH	183	{ \
d877322b SH	184	unsigned long long __gu_tmp; \
61e85e36 JB	185	__asm__ __volatile__( \
	186	"1: l.lwz %1,0(%2)\n" \
	187	"2: l.lwz %H1,4(%2)\n" \
	188	"3:\n" \
	189	".section .fixup,\"ax\"\n" \
	190	"4: l.addi %0,r0,%3\n" \
	191	" l.addi %1,r0,0\n" \
	192	" l.addi %H1,r0,0\n" \
	193	" l.j 3b\n" \
	194	" l.nop\n" \
	195	".previous\n" \
	196	".section __ex_table,\"a\"\n" \
	197	" .align 2\n" \
	198	" .long 1b,4b\n" \
	199	" .long 2b,4b\n" \
	200	".previous" \
d877322b SH	201	: "=r"(err), "=&r"(__gu_tmp) \
	202	: "r"(addr), "i"(-EFAULT), "0"(err)); \
	203	(x) = (__typeof__(*(addr)))( \
	204	(__typeof__((x)-(x)))__gu_tmp); \
	205	}
61e85e36 JB	206
	207	/* more complex routines */
	208
	209	extern unsigned long __must_check
	210	__copy_tofrom_user(void to, const void from, unsigned long size);
61e85e36	211	static inline unsigned long
ab89866b	212	raw_copy_from_user(void to, const void __user from, unsigned long size)
61e85e36	213	{
ab89866b	214	return __copy_tofrom_user(to, (__force const void *)from, size);
61e85e36	215	}
61e85e36	216	static inline unsigned long
9e9da641	217	raw_copy_to_user(void __user to, const void from, unsigned long size)
61e85e36	218	{
ab89866b	219	return __copy_tofrom_user((__force void *)to, from, size);
61e85e36	220	}
ab89866b AV	221	#define INLINE_COPY_FROM_USER
ab89866b AV	222	#define INLINE_COPY_TO_USER
61e85e36	223
17fcd83c	224	extern unsigned long __clear_user(void __user *addr, unsigned long size);
61e85e36 JB	225
61e85e36 JB	226	static inline __must_check unsigned long
17fcd83c	227	clear_user(void __user *addr, unsigned long size)
61e85e36	228	{
96d4f267	229	if (likely(access_ok(addr, size)))
acb2505d	230	size = __clear_user(addr, size);
61e85e36 JB	231	return size;
	232	}
	233
603d6637	234	extern long strncpy_from_user(char dest, const char __user src, long count);
61e85e36	235
b48b2c3e	236	extern __must_check long strnlen_user(const char __user *str, long n);
61e85e36 JB	237
61e85e36 JB	238	#endif /* __ASM_OPENRISC_UACCESS_H */