[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 - 1) > (memory_start + memory_size - 1)));
}

#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,\"ax\"\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, %1, r0;"	\
			"	addik	%0, %0, -1;"	\
			"	bneid	%0, 1b;"	\
			"	addik	%1, %1, 1;"	\
			"2:			"	\
			__EX_TABLE_SECTION		\
			".word	1b,2b;"			\
			".previous;"			\
		: "=r"(n), "=r"(to)			\
		: "0"(n), "1"(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);
}

/* 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)			\
	);							\
})

/**
 * 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)						\
	__get_user_check((x), (ptr), sizeof(*(ptr)))

#define __get_user_check(x, ptr, size)					\
({									\
	unsigned long __gu_val = 0;					\
	const typeof(*(ptr)) __user *__gu_addr = (ptr);			\
	int __gu_err = 0;						\
									\
	if (access_ok(VERIFY_READ, __gu_addr, size)) {			\
		switch (size) {						\
		case 1:							\
			__get_user_asm("lbu", __gu_addr, __gu_val,	\
				       __gu_err);			\
			break;						\
		case 2:							\
			__get_user_asm("lhu", __gu_addr, __gu_val,	\
				       __gu_err);			\
			break;						\
		case 4:							\
			__get_user_asm("lw", __gu_addr, __gu_val,	\
				       __gu_err);			\
			break;						\
		default:						\
			__gu_err = __user_bad();			\
			break;						\
		}							\
	} else {							\
		__gu_err = -EFAULT;					\
	}								\
	x = (typeof(*(ptr)))__gu_val;					\
	__gu_err;							\
})

#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;							\
})


#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)	\
		);						\
})

/**
 * 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(x, ptr)						\
	__put_user_check((x), (ptr), sizeof(*(ptr)))

#define __put_user_check(x, ptr, size)					\
({									\
	typeof(*(ptr)) volatile __pu_val = x;					\
	typeof(*(ptr)) __user *__pu_addr = (ptr);			\
	int __pu_err = 0;						\
									\
	if (access_ok(VERIFY_WRITE, __pu_addr, size)) {			\
		switch (size) {						\
		case 1:							\
			__put_user_asm("sb", __pu_addr, __pu_val,	\
				       __pu_err);			\
			break;						\
		case 2:							\
			__put_user_asm("sh", __pu_addr, __pu_val,	\
				       __pu_err);			\
			break;						\
		case 4:							\
			__put_user_asm("sw", __pu_addr, __pu_val,	\
				       __pu_err);			\
			break;						\
		case 8:							\
			__put_user_asm_8(__pu_addr, __pu_val, __pu_err);\
			break;						\
		default:						\
			__pu_err = __user_bad();			\
			break;						\
		}							\
	} else {							\
		__pu_err = -EFAULT;					\
	}								\
	__pu_err;							\
})

#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;							\
})


/* copy_to_from_user */
#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);
	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);
	return n;
}

/*
 * Copy a null terminated string from userspace.
 */
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);
}

/*
 * Return the size of a string (including the ending 0)
 *
 * Return 0 on exception, a value greater than N if too long
 */
extern int __strnlen_user(const char __user *sstr, int len);

static inline long strnlen_user(const char __user *src, long n)
{
	if (!access_ok(VERIFY_READ, src, 1))
		return 0;
	return __strnlen_user(src, n);
}

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

#endif /* _ASM_MICROBLAZE_UACCESS_H */
Commit	Line	Data
	1	/*
	2	* Copyright (C) 2008-2009 Michal Simek <monstr@monstr.eu>
	3	* Copyright (C) 2008-2009 PetaLogix
	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>
	25	#include <linux/string.h>
	26
	27	#define VERIFY_READ 0
	28	#define VERIFY_WRITE 1
	29
	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
	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	};
	73
	74	/* Returns 0 if exception not found and fixup otherwise. */
	75	extern unsigned long search_exception_table(unsigned long);
	76
	77	#ifndef CONFIG_MMU
	78
	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 - 1) > (memory_start + memory_size - 1)));
	84	}
	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)
	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,\"ax\"\n"
	112	#endif
	113
	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, %1, r0;" \
	124	" addik %0, %0, -1;" \
	125	" bneid %0, 1b;" \
	126	" addik %1, %1, 1;" \
	127	"2: " \
	128	__EX_TABLE_SECTION \
	129	".word 1b,2b;" \
	130	".previous;" \
	131	: "=r"(n), "=r"(to) \
	132	: "0"(n), "1"(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
	147	/* put_user and get_user macros */
	148	extern long __user_bad(void);
	149
	150	#define __get_user_asm(insn, __gu_ptr, __gu_val, __gu_err) \
	151	({ \
	152	__asm__ __volatile__ ( \
	153	"1:" insn " %1, %2, r0;" \
	154	" addk %0, r0, r0;" \
	155	"2: " \
	156	__FIXUP_SECTION \
	157	"3: brid 2b;" \
	158	" addik %0, r0, %3;" \
	159	".previous;" \
	160	__EX_TABLE_SECTION \
	161	".word 1b,3b;" \
	162	".previous;" \
	163	: "=&r"(__gu_err), "=r"(__gu_val) \
	164	: "r"(__gu_ptr), "i"(-EFAULT) \
	165	); \
	166	})
	167
	168	/**
	169	* get_user: - Get a simple variable from user space.
	170	* @x: Variable to store result.
	171	* @ptr: Source address, in user space.
	172	*
	173	* Context: User context only. This function may sleep.
	174	*
	175	* This macro copies a single simple variable from user space to kernel
	176	* space. It supports simple types like char and int, but not larger
	177	* data types like structures or arrays.
	178	*
	179	* @ptr must have pointer-to-simple-variable type, and the result of
	180	* dereferencing @ptr must be assignable to @x without a cast.
	181	*
	182	* Returns zero on success, or -EFAULT on error.
	183	* On error, the variable @x is set to zero.
	184	*/
	185	#define get_user(x, ptr) \
	186	__get_user_check((x), (ptr), sizeof(*(ptr)))
	187
	188	#define __get_user_check(x, ptr, size) \
	189	({ \
	190	unsigned long __gu_val = 0; \
	191	const typeof((ptr)) __user __gu_addr = (ptr); \
	192	int __gu_err = 0; \
	193	\
	194	if (access_ok(VERIFY_READ, __gu_addr, size)) { \
	195	switch (size) { \
	196	case 1: \
	197	__get_user_asm("lbu", __gu_addr, __gu_val, \
	198	__gu_err); \
	199	break; \
	200	case 2: \
	201	__get_user_asm("lhu", __gu_addr, __gu_val, \
	202	__gu_err); \
	203	break; \
	204	case 4: \
	205	__get_user_asm("lw", __gu_addr, __gu_val, \
	206	__gu_err); \
	207	break; \
	208	default: \
	209	__gu_err = __user_bad(); \
	210	break; \
	211	} \
	212	} else { \
	213	__gu_err = -EFAULT; \
	214	} \
	215	x = (typeof(*(ptr)))__gu_val; \
	216	__gu_err; \
	217	})
	218
	219	#define __get_user(x, ptr) \
	220	({ \
	221	unsigned long __gu_val; \
	222	/unsigned long __gu_ptr = (unsigned long)(ptr);/ \
	223	long __gu_err; \
	224	switch (sizeof(*(ptr))) { \
	225	case 1: \
	226	__get_user_asm("lbu", (ptr), __gu_val, __gu_err); \
	227	break; \
	228	case 2: \
	229	__get_user_asm("lhu", (ptr), __gu_val, __gu_err); \
	230	break; \
	231	case 4: \
	232	__get_user_asm("lw", (ptr), __gu_val, __gu_err); \
	233	break; \
	234	default: \
	235	/* __gu_val = 0; __gu_err = -EINVAL;*/ __gu_err = __user_bad();\
	236	} \
	237	x = (__typeof__(*(ptr))) __gu_val; \
	238	__gu_err; \
	239	})
	240
	241
	242	#define __put_user_asm(insn, __gu_ptr, __gu_val, __gu_err) \
	243	({ \
	244	__asm__ __volatile__ ( \
	245	"1:" insn " %1, %2, r0;" \
	246	" addk %0, r0, r0;" \
	247	"2: " \
	248	__FIXUP_SECTION \
	249	"3: brid 2b;" \
	250	" addik %0, r0, %3;" \
	251	".previous;" \
	252	__EX_TABLE_SECTION \
	253	".word 1b,3b;" \
	254	".previous;" \
	255	: "=&r"(__gu_err) \
	256	: "r"(__gu_val), "r"(__gu_ptr), "i"(-EFAULT) \
	257	); \
	258	})
	259
	260	#define __put_user_asm_8(__gu_ptr, __gu_val, __gu_err) \
	261	({ \
	262	__asm__ __volatile__ (" lwi %0, %1, 0;" \
	263	"1: swi %0, %2, 0;" \
	264	" lwi %0, %1, 4;" \
	265	"2: swi %0, %2, 4;" \
	266	" addk %0, r0, r0;" \
	267	"3: " \
	268	__FIXUP_SECTION \
	269	"4: brid 3b;" \
	270	" addik %0, r0, %3;" \
	271	".previous;" \
	272	__EX_TABLE_SECTION \
	273	".word 1b,4b,2b,4b;" \
	274	".previous;" \
	275	: "=&r"(__gu_err) \
	276	: "r"(&__gu_val), "r"(__gu_ptr), "i"(-EFAULT) \
	277	); \
	278	})
	279
	280	/**
	281	* put_user: - Write a simple value into user space.
	282	* @x: Value to copy to user space.
	283	* @ptr: Destination address, in user space.
	284	*
	285	* Context: User context only. This function may sleep.
	286	*
	287	* This macro copies a single simple value from kernel space to user
	288	* space. It supports simple types like char and int, but not larger
	289	* data types like structures or arrays.
	290	*
	291	* @ptr must have pointer-to-simple-variable type, and @x must be assignable
	292	* to the result of dereferencing @ptr.
	293	*
	294	* Returns zero on success, or -EFAULT on error.
	295	*/
	296	#define put_user(x, ptr) \
	297	__put_user_check((x), (ptr), sizeof(*(ptr)))
	298
	299	#define __put_user_check(x, ptr, size) \
	300	({ \
	301	typeof(*(ptr)) volatile __pu_val = x; \
	302	typeof((ptr)) __user __pu_addr = (ptr); \
	303	int __pu_err = 0; \
	304	\
	305	if (access_ok(VERIFY_WRITE, __pu_addr, size)) { \
	306	switch (size) { \
	307	case 1: \
	308	__put_user_asm("sb", __pu_addr, __pu_val, \
	309	__pu_err); \
	310	break; \
	311	case 2: \
	312	__put_user_asm("sh", __pu_addr, __pu_val, \
	313	__pu_err); \
	314	break; \
	315	case 4: \
	316	__put_user_asm("sw", __pu_addr, __pu_val, \
	317	__pu_err); \
	318	break; \
	319	case 8: \
	320	__put_user_asm_8(__pu_addr, __pu_val, __pu_err);\
	321	break; \
	322	default: \
	323	__pu_err = __user_bad(); \
	324	break; \
	325	} \
	326	} else { \
	327	__pu_err = -EFAULT; \
	328	} \
	329	__pu_err; \
	330	})
	331
	332	#define __put_user(x, ptr) \
	333	({ \
	334	__typeof__(*(ptr)) volatile __gu_val = (x); \
	335	long __gu_err = 0; \
	336	switch (sizeof(__gu_val)) { \
	337	case 1: \
	338	__put_user_asm("sb", (ptr), __gu_val, __gu_err); \
	339	break; \
	340	case 2: \
	341	__put_user_asm("sh", (ptr), __gu_val, __gu_err); \
	342	break; \
	343	case 4: \
	344	__put_user_asm("sw", (ptr), __gu_val, __gu_err); \
	345	break; \
	346	case 8: \
	347	__put_user_asm_8((ptr), __gu_val, __gu_err); \
	348	break; \
	349	default: \
	350	/__gu_err = -EINVAL;/ __gu_err = __user_bad(); \
	351	} \
	352	__gu_err; \
	353	})
	354
	355
	356	/* copy_to_from_user */
	357	#define __copy_from_user(to, from, n) \
	358	__copy_tofrom_user((__force void __user *)(to), \
	359	(void __user *)(from), (n))
	360	#define __copy_from_user_inatomic(to, from, n) \
	361	__copy_from_user((to), (from), (n))
	362
	363	static inline long copy_from_user(void *to,
	364	const void __user *from, unsigned long n)
	365	{
	366	might_sleep();
	367	if (access_ok(VERIFY_READ, from, n))
	368	return __copy_from_user(to, from, n);
	369	return n;
	370	}
	371
	372	#define __copy_to_user(to, from, n) \
	373	__copy_tofrom_user((void __user *)(to), \
	374	(__force const void __user *)(from), (n))
	375	#define __copy_to_user_inatomic(to, from, n) __copy_to_user((to), (from), (n))
	376
	377	static inline long copy_to_user(void __user *to,
	378	const void *from, unsigned long n)
	379	{
	380	might_sleep();
	381	if (access_ok(VERIFY_WRITE, to, n))
	382	return __copy_to_user(to, from, n);
	383	return n;
	384	}
	385
	386	/*
	387	* Copy a null terminated string from userspace.
	388	*/
	389	extern int __strncpy_user(char to, const char __user from, int len);
	390
	391	#define __strncpy_from_user __strncpy_user
	392
	393	static inline long
	394	strncpy_from_user(char dst, const char __user src, long count)
	395	{
	396	if (!access_ok(VERIFY_READ, src, 1))
	397	return -EFAULT;
	398	return __strncpy_from_user(dst, src, count);
	399	}
	400
	401	/*
	402	* Return the size of a string (including the ending 0)
	403	*
	404	* Return 0 on exception, a value greater than N if too long
	405	*/
	406	extern int __strnlen_user(const char __user *sstr, int len);
	407
	408	static inline long strnlen_user(const char __user *src, long n)
	409	{
	410	if (!access_ok(VERIFY_READ, src, 1))
	411	return 0;
	412	return __strnlen_user(src, n);
	413	}
	414
	415	#endif /* __ASSEMBLY__ */
	416	#endif /* __KERNEL__ */
	417
	418	#endif /* _ASM_MICROBLAZE_UACCESS_H */