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

/*
 * Copyright (C) 2008-2009 Michal Simek <monstr@monstr.eu>
 * Copyright (C) 2008-2009 PetaLogix
 * Copyright (C) 2006 Atmark Techno, Inc.
 *
 * 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_MICROBLAZE_UACCESS_H
#define _ASM_MICROBLAZE_UACCESS_H

#ifdef __KERNEL__
#ifndef __ASSEMBLY__

#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/sched.h> /* RLIMIT_FSIZE */
#include <linux/mm.h>

#include <asm/mmu.h>
#include <asm/page.h>
#include <asm/pgtable.h>
#include <linux/string.h>

#define VERIFY_READ	0
#define VERIFY_WRITE	1

/*
 * On Microblaze the fs value is actually the top of the corresponding
 * address space.
 *
 * The fs value determines whether argument validity checking should be
 * performed or not. If get_fs() == USER_DS, checking is performed, with
 * get_fs() == KERNEL_DS, checking is bypassed.
 *
 * For historical reasons, these macros are grossly misnamed.
 *
 * For non-MMU arch like Microblaze, KERNEL_DS and USER_DS is equal.
 */
# define MAKE_MM_SEG(s)       ((mm_segment_t) { (s) })

#  ifndef CONFIG_MMU
#  define KERNEL_DS	MAKE_MM_SEG(0)
#  define USER_DS	KERNEL_DS
#  else
#  define KERNEL_DS	MAKE_MM_SEG(0xFFFFFFFF)
#  define USER_DS	MAKE_MM_SEG(TASK_SIZE - 1)
#  endif

# define get_ds()	(KERNEL_DS)
# define get_fs()	(current_thread_info()->addr_limit)
# define set_fs(val)	(current_thread_info()->addr_limit = (val))

# define segment_eq(a, b)	((a).seg == (b).seg)

/*
 * The exception table consists of pairs of addresses: the first is the
 * address of an instruction that is allowed to fault, and the second is
 * the address at which the program should continue. No registers are
 * modified, so it is entirely up to the continuation code to figure out
 * what to do.
 *
 * All the routines below use bits of fixup code that are out of line
 * with the main instruction path. This means when everything is well,
 * we don't even have to jump over them. Further, they do not intrude
 * on our cache or tlb entries.
 */
struct exception_table_entry {
	unsigned long insn, fixup;
};

/* Returns 0 if exception not found and fixup otherwise.  */
extern unsigned long search_exception_table(unsigned long);

#ifndef CONFIG_MMU

/* Check against bounds of physical memory */
static inline int ___range_ok(unsigned long addr, unsigned long size)
{
	return ((addr < memory_start) ||
		((addr + size) > memory_end));
}

#define __range_ok(addr, size) \
		___range_ok((unsigned long)(addr), (unsigned long)(size))

#define access_ok(type, addr, size) (__range_ok((addr), (size)) == 0)

#else

/*
 * Address is valid if:
 *  - "addr", "addr + size" and "size" are all below the limit
 */
#define access_ok(type, addr, size) \
	(get_fs().seg > (((unsigned long)(addr)) | \
		(size) | ((unsigned long)(addr) + (size))))

/* || printk("access_ok failed for %s at 0x%08lx (size %d), seg 0x%08x\n",
 type?"WRITE":"READ",addr,size,get_fs().seg)) */

#endif

#ifdef CONFIG_MMU
# define __FIXUP_SECTION	".section .fixup,\"ax\"\n"
# define __EX_TABLE_SECTION	".section __ex_table,\"a\"\n"
#else
# define __FIXUP_SECTION	".section .discard,\"ax\"\n"
# define __EX_TABLE_SECTION	".section .discard,\"a\"\n"
#endif

extern unsigned long __copy_tofrom_user(void __user *to,
		const void __user *from, unsigned long size);

/* Return: number of not copied bytes, i.e. 0 if OK or non-zero if fail. */
static inline unsigned long __must_check __clear_user(void __user *to,
							unsigned long n)
{
	/* normal memset with two words to __ex_table */
	__asm__ __volatile__ (				\
			"1:	sb	r0, %2, r0;"	\
			"	addik	%0, %0, -1;"	\
			"	bneid	%0, 1b;"	\
			"	addik	%2, %2, 1;"	\
			"2:			"	\
			__EX_TABLE_SECTION		\
			".word	1b,2b;"			\
			".previous;"			\
		: "=r"(n)				\
		: "0"(n), "r"(to)
	);
	return n;
}

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

	return __clear_user(to, n);
}

#ifndef CONFIG_MMU

/* Undefined function to trigger linker error */
extern int bad_user_access_length(void);

/* FIXME this is function for optimalization -> memcpy */
#define __get_user(var, ptr)				\
({							\
	int __gu_err = 0;				\
	switch (sizeof(*(ptr))) {			\
	case 1:						\
	case 2:						\
	case 4:						\
		(var) = *(ptr);				\
		break;					\
	case 8:						\
		memcpy((void *) &(var), (ptr), 8);	\
		break;					\
	default:					\
		(var) = 0;				\
		__gu_err = __get_user_bad();		\
		break;					\
	}						\
	__gu_err;					\
})

#define __get_user_bad()	(bad_user_access_length(), (-EFAULT))

/* FIXME is not there defined __pu_val */
#define __put_user(var, ptr)					\
({								\
	int __pu_err = 0;					\
	switch (sizeof(*(ptr))) {				\
	case 1:							\
	case 2:							\
	case 4:							\
		*(ptr) = (var);					\
		break;						\
	case 8: {						\
		typeof(*(ptr)) __pu_val = (var);		\
		memcpy(ptr, &__pu_val, sizeof(__pu_val));	\
		}						\
		break;						\
	default:						\
		__pu_err = __put_user_bad();			\
		break;						\
	}							\
	__pu_err;						\
})

#define __put_user_bad()	(bad_user_access_length(), (-EFAULT))

#define put_user(x, ptr)	__put_user((x), (ptr))
#define get_user(x, ptr)	__get_user((x), (ptr))

#define copy_to_user(to, from, n)	(memcpy((to), (from), (n)), 0)
#define copy_from_user(to, from, n)	(memcpy((to), (from), (n)), 0)

#define __copy_to_user(to, from, n)	(copy_to_user((to), (from), (n)))
#define __copy_from_user(to, from, n)	(copy_from_user((to), (from), (n)))
#define __copy_to_user_inatomic(to, from, n) \
			(__copy_to_user((to), (from), (n)))
#define __copy_from_user_inatomic(to, from, n) \
			(__copy_from_user((to), (from), (n)))

extern long strncpy_from_user(char *dst, const char *src, long count);
extern long strnlen_user(const char *src, long count);

#else /* CONFIG_MMU */

/* put_user and get_user macros */

extern long __user_bad(void);

#define __get_user_asm(insn, __gu_ptr, __gu_val, __gu_err)	\
({								\
	__asm__ __volatile__ (					\
			"1:"	insn	" %1, %2, r0;"		\
			"	addk	%0, r0, r0;"		\
			"2:			"		\
			__FIXUP_SECTION				\
			"3:	brid	2b;	"		\
			"	addik	%0, r0, %3;"		\
			".previous;"				\
			__EX_TABLE_SECTION			\
			".word	1b,3b;"				\
			".previous;"				\
		: "=&r"(__gu_err), "=r"(__gu_val)		\
		: "r"(__gu_ptr), "i"(-EFAULT)			\
	);							\
})

#define __get_user(x, ptr)						\
({									\
	unsigned long __gu_val;						\
	/*unsigned long __gu_ptr = (unsigned long)(ptr);*/		\
	long __gu_err;							\
	switch (sizeof(*(ptr))) {					\
	case 1:								\
		__get_user_asm("lbu", (ptr), __gu_val, __gu_err);	\
		break;							\
	case 2:								\
		__get_user_asm("lhu", (ptr), __gu_val, __gu_err);	\
		break;							\
	case 4:								\
		__get_user_asm("lw", (ptr), __gu_val, __gu_err);	\
		break;							\
	default:							\
		/* __gu_val = 0; __gu_err = -EINVAL;*/ __gu_err = __user_bad();\
	}								\
	x = (__typeof__(*(ptr))) __gu_val;				\
	__gu_err;							\
})

/**
 * get_user: - Get a simple variable from user space.
 * @x:   Variable to store result.
 * @ptr: Source address, in user space.
 *
 * Context: User context only.  This function may sleep.
 *
 * This macro copies a single simple variable from user space to kernel
 * space.  It supports simple types like char and int, but not larger
 * data types like structures or arrays.
 *
 * @ptr must have pointer-to-simple-variable type, and the result of
 * dereferencing @ptr must be assignable to @x without a cast.
 *
 * Returns zero on success, or -EFAULT on error.
 * On error, the variable @x is set to zero.
 */

#define get_user(x, ptr)						\
({									\
	access_ok(VERIFY_READ, (ptr), sizeof(*(ptr)))			\
		? __get_user((x), (ptr)) : -EFAULT;			\
})

/**
 * put_user: - Write a simple value into user space.
 * @x:   Value to copy to user space.
 * @ptr: Destination address, in user space.
 *
 * Context: User context only.  This function may sleep.
 *
 * This macro copies a single simple value from kernel space to user
 * space.  It supports simple types like char and int, but not larger
 * data types like structures or arrays.
 *
 * @ptr must have pointer-to-simple-variable type, and @x must be assignable
 * to the result of dereferencing @ptr.
 *
 * Returns zero on success, or -EFAULT on error.
 */

#define __put_user_asm(insn, __gu_ptr, __gu_val, __gu_err)	\
({								\
	__asm__ __volatile__ (					\
			"1:"	insn	" %1, %2, r0;"		\
			"	addk	%0, r0, r0;"		\
			"2:			"		\
			__FIXUP_SECTION				\
			"3:	brid	2b;"			\
			"	addik	%0, r0, %3;"		\
			".previous;"				\
			__EX_TABLE_SECTION			\
			".word	1b,3b;"				\
			".previous;"				\
		: "=&r"(__gu_err)				\
		: "r"(__gu_val), "r"(__gu_ptr), "i"(-EFAULT)	\
	);							\
})

#define __put_user_asm_8(__gu_ptr, __gu_val, __gu_err)		\
({								\
	__asm__ __volatile__ ("	lwi	%0, %1, 0;"		\
			"1:	swi	%0, %2, 0;"		\
			"	lwi	%0, %1, 4;"		\
			"2:	swi	%0, %2, 4;"		\
			"	addk	%0, r0, r0;"		\
			"3:				"	\
			__FIXUP_SECTION				\
			"4:	brid	3b;"			\
			"	addik	%0, r0, %3;"		\
			".previous;"				\
			__EX_TABLE_SECTION			\
			".word	1b,4b,2b,4b;"			\
			".previous;"				\
		: "=&r"(__gu_err)				\
		: "r"(&__gu_val), "r"(__gu_ptr), "i"(-EFAULT)	\
		);						\
})

#define __put_user(x, ptr)						\
({									\
	__typeof__(*(ptr)) volatile __gu_val = (x);			\
	long __gu_err = 0;						\
	switch (sizeof(__gu_val)) {					\
	case 1:								\
		__put_user_asm("sb", (ptr), __gu_val, __gu_err);	\
		break;							\
	case 2: 							\
		__put_user_asm("sh", (ptr), __gu_val, __gu_err);	\
		break;							\
	case 4:								\
		__put_user_asm("sw", (ptr), __gu_val, __gu_err);	\
		break;							\
	case 8:								\
		__put_user_asm_8((ptr), __gu_val, __gu_err);		\
		break;							\
	default:							\
		/*__gu_err = -EINVAL;*/	__gu_err = __user_bad();	\
	}								\
	__gu_err;							\
})

#define put_user(x, ptr)						\
({									\
	access_ok(VERIFY_WRITE, (ptr), sizeof(*(ptr)))			\
		? __put_user((x), (ptr)) : -EFAULT;			\
})

#define __copy_from_user(to, from, n)	\
	__copy_tofrom_user((__force void __user *)(to), \
				(void __user *)(from), (n))
#define __copy_from_user_inatomic(to, from, n) \
		copy_from_user((to), (from), (n))

static inline long copy_from_user(void *to,
		const void __user *from, unsigned long n)
{
	might_sleep();
	if (access_ok(VERIFY_READ, from, n))
		return __copy_from_user(to, from, n);
	else
		return n;
}

#define __copy_to_user(to, from, n)	\
		__copy_tofrom_user((void __user *)(to), \
			(__force const void __user *)(from), (n))
#define __copy_to_user_inatomic(to, from, n)	copy_to_user((to), (from), (n))

static inline long copy_to_user(void __user *to,
		const void *from, unsigned long n)
{
	might_sleep();
	if (access_ok(VERIFY_WRITE, to, n))
		return __copy_to_user(to, from, n);
	else
		return n;
}

extern int __strncpy_user(char *to, const char __user *from, int len);

#define __strncpy_from_user	__strncpy_user

static inline long
strncpy_from_user(char *dst, const char __user *src, long count)
{
	if (!access_ok(VERIFY_READ, src, 1))
		return -EFAULT;
	return __strncpy_from_user(dst, src, count);
}

extern int __strnlen_user(const char __user *sstr, int len);

#define strnlen_user(str, len)	\
		(access_ok(VERIFY_READ, str, 1) ? __strnlen_user(str, len) : 0)

#endif /* CONFIG_MMU */

#endif  /* __ASSEMBLY__ */
#endif /* __KERNEL__ */

#endif /* _ASM_MICROBLAZE_UACCESS_H */
Commit	Line	Data
2660663f	1	/*
0d6de953 MS	2	* Copyright (C) 2008-2009 Michal Simek <monstr@monstr.eu>
0d6de953 MS	3	* Copyright (C) 2008-2009 PetaLogix
2660663f MS	4	* Copyright (C) 2006 Atmark Techno, Inc.
	5	*
	6	* This file is subject to the terms and conditions of the GNU General Public
	7	* License. See the file "COPYING" in the main directory of this archive
	8	* for more details.
	9	*/
	10
	11	#ifndef _ASM_MICROBLAZE_UACCESS_H
	12	#define _ASM_MICROBLAZE_UACCESS_H
	13
	14	#ifdef __KERNEL__
	15	#ifndef __ASSEMBLY__
	16
	17	#include <linux/kernel.h>
	18	#include <linux/errno.h>
	19	#include <linux/sched.h> /* RLIMIT_FSIZE */
	20	#include <linux/mm.h>
	21
	22	#include <asm/mmu.h>
	23	#include <asm/page.h>
	24	#include <asm/pgtable.h>
2660663f MS	25	#include <linux/string.h>
	26
	27	#define VERIFY_READ 0
	28	#define VERIFY_WRITE 1
	29
40db0834 MS	30	/*
	31	* On Microblaze the fs value is actually the top of the corresponding
	32	* address space.
	33	*
	34	* The fs value determines whether argument validity checking should be
	35	* performed or not. If get_fs() == USER_DS, checking is performed, with
	36	* get_fs() == KERNEL_DS, checking is bypassed.
	37	*
	38	* For historical reasons, these macros are grossly misnamed.
	39	*
	40	* For non-MMU arch like Microblaze, KERNEL_DS and USER_DS is equal.
	41	*/
	42	# define MAKE_MM_SEG(s) ((mm_segment_t) { (s) })
	43
	44	# ifndef CONFIG_MMU
	45	# define KERNEL_DS MAKE_MM_SEG(0)
	46	# define USER_DS KERNEL_DS
	47	# else
	48	# define KERNEL_DS MAKE_MM_SEG(0xFFFFFFFF)
	49	# define USER_DS MAKE_MM_SEG(TASK_SIZE - 1)
	50	# endif
	51
	52	# define get_ds() (KERNEL_DS)
	53	# define get_fs() (current_thread_info()->addr_limit)
	54	# define set_fs(val) (current_thread_info()->addr_limit = (val))
	55
	56	# define segment_eq(a, b) ((a).seg == (b).seg)
	57
357bc3c9 MS	58	/*
	59	* The exception table consists of pairs of addresses: the first is the
	60	* address of an instruction that is allowed to fault, and the second is
	61	* the address at which the program should continue. No registers are
	62	* modified, so it is entirely up to the continuation code to figure out
	63	* what to do.
	64	*
	65	* All the routines below use bits of fixup code that are out of line
	66	* with the main instruction path. This means when everything is well,
	67	* we don't even have to jump over them. Further, they do not intrude
	68	* on our cache or tlb entries.
	69	*/
	70	struct exception_table_entry {
	71	unsigned long insn, fixup;
	72	};
40db0834	73
527bdb52 MS	74	/* Returns 0 if exception not found and fixup otherwise. */
	75	extern unsigned long search_exception_table(unsigned long);
	76
0d6de953 MS	77	#ifndef CONFIG_MMU
0d6de953 MS	78
60a729f7 MS	79	/* Check against bounds of physical memory */
	80	static inline int ___range_ok(unsigned long addr, unsigned long size)
	81	{
	82	return ((addr < memory_start) \|\|
	83	((addr + size) > memory_end));
	84	}
2660663f MS	85
	86	#define __range_ok(addr, size) \
	87	___range_ok((unsigned long)(addr), (unsigned long)(size))
	88
	89	#define access_ok(type, addr, size) (__range_ok((addr), (size)) == 0)
40b1156d MS	90
	91	#else
	92
	93	/*
	94	* Address is valid if:
	95	* - "addr", "addr + size" and "size" are all below the limit
	96	*/
	97	#define access_ok(type, addr, size) \
	98	(get_fs().seg > (((unsigned long)(addr)) \| \
	99	(size) \| ((unsigned long)(addr) + (size))))
	100
	101	/* \|\| printk("access_ok failed for %s at 0x%08lx (size %d), seg 0x%08x\n",
	102	type?"WRITE":"READ",addr,size,get_fs().seg)) */
	103
	104	#endif
	105
	106	#ifdef CONFIG_MMU
	107	# define __FIXUP_SECTION ".section .fixup,\"ax\"\n"
	108	# define __EX_TABLE_SECTION ".section __ex_table,\"a\"\n"
	109	#else
	110	# define __FIXUP_SECTION ".section .discard,\"ax\"\n"
	111	# define __EX_TABLE_SECTION ".section .discard,\"a\"\n"
	112	#endif
	113
527bdb52 MS	114	extern unsigned long __copy_tofrom_user(void __user *to,
	115	const void __user *from, unsigned long size);
	116
	117	/* Return: number of not copied bytes, i.e. 0 if OK or non-zero if fail. */
	118	static inline unsigned long __must_check __clear_user(void __user *to,
	119	unsigned long n)
	120	{
	121	/* normal memset with two words to __ex_table */
	122	__asm__ __volatile__ ( \
	123	"1: sb r0, %2, r0;" \
	124	" addik %0, %0, -1;" \
	125	" bneid %0, 1b;" \
	126	" addik %2, %2, 1;" \
	127	"2: " \
	128	__EX_TABLE_SECTION \
	129	".word 1b,2b;" \
	130	".previous;" \
	131	: "=r"(n) \
	132	: "0"(n), "r"(to)
	133	);
	134	return n;
	135	}
	136
	137	static inline unsigned long __must_check clear_user(void __user *to,
	138	unsigned long n)
	139	{
	140	might_sleep();
	141	if (unlikely(!access_ok(VERIFY_WRITE, to, n)))
	142	return n;
	143
	144	return __clear_user(to, n);
	145	}
	146
40b1156d	147	#ifndef CONFIG_MMU
2660663f	148
838d2406 AB	149	/* Undefined function to trigger linker error */
	150	extern int bad_user_access_length(void);
	151
2660663f	152	/* FIXME this is function for optimalization -> memcpy */
0d6de953 MS	153	#define __get_user(var, ptr) \
	154	({ \
	155	int __gu_err = 0; \
	156	switch (sizeof(*(ptr))) { \
	157	case 1: \
	158	case 2: \
	159	case 4: \
	160	(var) = *(ptr); \
	161	break; \
	162	case 8: \
	163	memcpy((void *) &(var), (ptr), 8); \
	164	break; \
	165	default: \
	166	(var) = 0; \
	167	__gu_err = __get_user_bad(); \
	168	break; \
	169	} \
	170	__gu_err; \
	171	})
2660663f MS	172
	173	#define __get_user_bad() (bad_user_access_length(), (-EFAULT))
	174
0d6de953	175	/* FIXME is not there defined __pu_val */
2660663f	176	#define __put_user(var, ptr) \
0d6de953 MS	177	({ \
	178	int __pu_err = 0; \
	179	switch (sizeof(*(ptr))) { \
	180	case 1: \
	181	case 2: \
	182	case 4: \
	183	*(ptr) = (var); \
	184	break; \
	185	case 8: { \
	186	typeof(*(ptr)) __pu_val = (var); \
	187	memcpy(ptr, &__pu_val, sizeof(__pu_val)); \
	188	} \
	189	break; \
	190	default: \
	191	__pu_err = __put_user_bad(); \
	192	break; \
	193	} \
	194	__pu_err; \
	195	})
2660663f MS	196
	197	#define __put_user_bad() (bad_user_access_length(), (-EFAULT))
	198
0d6de953 MS	199	#define put_user(x, ptr) __put_user((x), (ptr))
0d6de953 MS	200	#define get_user(x, ptr) __get_user((x), (ptr))
2660663f	201
0d6de953 MS	202	#define copy_to_user(to, from, n) (memcpy((to), (from), (n)), 0)
0d6de953 MS	203	#define copy_from_user(to, from, n) (memcpy((to), (from), (n)), 0)
2660663f	204
0d6de953 MS	205	#define __copy_to_user(to, from, n) (copy_to_user((to), (from), (n)))
	206	#define __copy_from_user(to, from, n) (copy_from_user((to), (from), (n)))
	207	#define __copy_to_user_inatomic(to, from, n) \
	208	(__copy_to_user((to), (from), (n)))
	209	#define __copy_from_user_inatomic(to, from, n) \
	210	(__copy_from_user((to), (from), (n)))
2660663f	211
0d6de953 MS	212	extern long strncpy_from_user(char dst, const char src, long count);
	213	extern long strnlen_user(const char *src, long count);
	214
	215	#else /* CONFIG_MMU */
	216
0dcb409d MS	217	/* put_user and get_user macros */
	218
	219	extern long __user_bad(void);
0d6de953	220
8b651aa4 MS	221	#define __get_user_asm(insn, __gu_ptr, __gu_val, __gu_err) \
	222	({ \
	223	__asm__ __volatile__ ( \
	224	"1:" insn " %1, %2, r0;" \
	225	" addk %0, r0, r0;" \
	226	"2: " \
	227	__FIXUP_SECTION \
	228	"3: brid 2b; " \
	229	" addik %0, r0, %3;" \
	230	".previous;" \
	231	__EX_TABLE_SECTION \
	232	".word 1b,3b;" \
	233	".previous;" \
	234	: "=&r"(__gu_err), "=r"(__gu_val) \
	235	: "r"(__gu_ptr), "i"(-EFAULT) \
	236	); \
0d6de953 MS	237	})
	238
	239	#define __get_user(x, ptr) \
	240	({ \
	241	unsigned long __gu_val; \
	242	/unsigned long __gu_ptr = (unsigned long)(ptr);/ \
	243	long __gu_err; \
	244	switch (sizeof(*(ptr))) { \
	245	case 1: \
	246	__get_user_asm("lbu", (ptr), __gu_val, __gu_err); \
	247	break; \
	248	case 2: \
	249	__get_user_asm("lhu", (ptr), __gu_val, __gu_err); \
	250	break; \
	251	case 4: \
	252	__get_user_asm("lw", (ptr), __gu_val, __gu_err); \
	253	break; \
	254	default: \
0dcb409d	255	/* __gu_val = 0; __gu_err = -EINVAL;*/ __gu_err = __user_bad();\
0d6de953 MS	256	} \
	257	x = (__typeof__(*(ptr))) __gu_val; \
	258	__gu_err; \
	259	})
	260
0dcb409d MS	261	/**
	262	* get_user: - Get a simple variable from user space.
	263	* @x: Variable to store result.
	264	* @ptr: Source address, in user space.
	265	*
	266	* Context: User context only. This function may sleep.
	267	*
	268	* This macro copies a single simple variable from user space to kernel
	269	* space. It supports simple types like char and int, but not larger
	270	* data types like structures or arrays.
	271	*
	272	* @ptr must have pointer-to-simple-variable type, and the result of
	273	* dereferencing @ptr must be assignable to @x without a cast.
	274	*
	275	* Returns zero on success, or -EFAULT on error.
	276	* On error, the variable @x is set to zero.
	277	*/
	278
8b651aa4 MS	279	#define get_user(x, ptr) \
	280	({ \
	281	access_ok(VERIFY_READ, (ptr), sizeof(*(ptr))) \
	282	? __get_user((x), (ptr)) : -EFAULT; \
	283	})
	284
0dcb409d MS	285	/**
	286	* put_user: - Write a simple value into user space.
	287	* @x: Value to copy to user space.
	288	* @ptr: Destination address, in user space.
	289	*
	290	* Context: User context only. This function may sleep.
	291	*
	292	* This macro copies a single simple value from kernel space to user
	293	* space. It supports simple types like char and int, but not larger
	294	* data types like structures or arrays.
	295	*
	296	* @ptr must have pointer-to-simple-variable type, and @x must be assignable
	297	* to the result of dereferencing @ptr.
	298	*
	299	* Returns zero on success, or -EFAULT on error.
	300	*/
	301
8b651aa4	302	#define __put_user_asm(insn, __gu_ptr, __gu_val, __gu_err) \
c77a9c4b MS	303	({ \
	304	__asm__ __volatile__ ( \
	305	"1:" insn " %1, %2, r0;" \
	306	" addk %0, r0, r0;" \
	307	"2: " \
	308	__FIXUP_SECTION \
8b651aa4	309	"3: brid 2b;" \
c77a9c4b MS	310	" addik %0, r0, %3;" \
	311	".previous;" \
	312	__EX_TABLE_SECTION \
	313	".word 1b,3b;" \
	314	".previous;" \
8b651aa4 MS	315	: "=&r"(__gu_err) \
8b651aa4 MS	316	: "r"(__gu_val), "r"(__gu_ptr), "i"(-EFAULT) \
c77a9c4b	317	); \
0d6de953 MS	318	})
0d6de953 MS	319
8b651aa4 MS	320	#define __put_user_asm_8(__gu_ptr, __gu_val, __gu_err) \
	321	({ \
	322	__asm__ __volatile__ (" lwi %0, %1, 0;" \
	323	"1: swi %0, %2, 0;" \
	324	" lwi %0, %1, 4;" \
	325	"2: swi %0, %2, 4;" \
	326	" addk %0, r0, r0;" \
	327	"3: " \
	328	__FIXUP_SECTION \
	329	"4: brid 3b;" \
	330	" addik %0, r0, %3;" \
	331	".previous;" \
	332	__EX_TABLE_SECTION \
	333	".word 1b,4b,2b,4b;" \
	334	".previous;" \
	335	: "=&r"(__gu_err) \
	336	: "r"(&__gu_val), "r"(__gu_ptr), "i"(-EFAULT) \
	337	); \
	338	})
c77a9c4b	339
0d6de953 MS	340	#define __put_user(x, ptr) \
0d6de953 MS	341	({ \
7bcb63b2	342	__typeof__(*(ptr)) volatile __gu_val = (x); \
0d6de953 MS	343	long __gu_err = 0; \
	344	switch (sizeof(__gu_val)) { \
	345	case 1: \
	346	__put_user_asm("sb", (ptr), __gu_val, __gu_err); \
	347	break; \
	348	case 2: \
	349	__put_user_asm("sh", (ptr), __gu_val, __gu_err); \
	350	break; \
	351	case 4: \
	352	__put_user_asm("sw", (ptr), __gu_val, __gu_err); \
	353	break; \
	354	case 8: \
	355	__put_user_asm_8((ptr), __gu_val, __gu_err); \
	356	break; \
	357	default: \
0dcb409d	358	/__gu_err = -EINVAL;/ __gu_err = __user_bad(); \
0d6de953 MS	359	} \
	360	__gu_err; \
	361	})
	362
8b651aa4 MS	363	#define put_user(x, ptr) \
	364	({ \
	365	access_ok(VERIFY_WRITE, (ptr), sizeof(*(ptr))) \
	366	? __put_user((x), (ptr)) : -EFAULT; \
0d6de953 MS	367	})
0d6de953 MS	368
4270690b MS	369	#define __copy_from_user(to, from, n) \
	370	__copy_tofrom_user((__force void __user *)(to), \
	371	(void __user *)(from), (n))
95dfbbe4 JW	372	#define __copy_from_user_inatomic(to, from, n) \
95dfbbe4 JW	373	copy_from_user((to), (from), (n))
0d6de953	374
4270690b MS	375	static inline long copy_from_user(void *to,
	376	const void __user *from, unsigned long n)
	377	{
	378	might_sleep();
	379	if (access_ok(VERIFY_READ, from, n))
	380	return __copy_from_user(to, from, n);
	381	else
	382	return n;
	383	}
	384
cc5a428b	385	#define __copy_to_user(to, from, n) \
4270690b	386	__copy_tofrom_user((void __user *)(to), \
cc5a428b	387	(__force const void __user *)(from), (n))
0d6de953 MS	388	#define __copy_to_user_inatomic(to, from, n) copy_to_user((to), (from), (n))
0d6de953 MS	389
cc5a428b MS	390	static inline long copy_to_user(void __user *to,
	391	const void *from, unsigned long n)
	392	{
	393	might_sleep();
	394	if (access_ok(VERIFY_WRITE, to, n))
	395	return __copy_to_user(to, from, n);
	396	else
	397	return n;
	398	}
	399
0d6de953	400	extern int __strncpy_user(char to, const char __user from, int len);
40e11e33 MS	401
	402	#define __strncpy_from_user __strncpy_user
	403
	404	static inline long
	405	strncpy_from_user(char dst, const char __user src, long count)
	406	{
	407	if (!access_ok(VERIFY_READ, src, 1))
	408	return -EFAULT;
	409	return __strncpy_from_user(dst, src, count);
	410	}
	411
0d6de953 MS	412	extern int __strnlen_user(const char __user *sstr, int len);
0d6de953 MS	413
0d6de953 MS	414	#define strnlen_user(str, len) \
0d6de953 MS	415	(access_ok(VERIFY_READ, str, 1) ? __strnlen_user(str, len) : 0)
2660663f	416
0d6de953	417	#endif /* CONFIG_MMU */
2660663f	418
2660663f MS	419	#endif /* __ASSEMBLY__ */
	420	#endif /* __KERNEL__ */
	421
	422	#endif /* _ASM_MICROBLAZE_UACCESS_H */