[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;
};

#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

#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)))

#define __clear_user(addr, n)	(memset((void *)(addr), 0, (n)), 0)

/* stejne s MMU */
static inline unsigned long clear_user(void *addr, unsigned long size)
{
	if (access_ok(VERIFY_WRITE, addr, size))
		size = __clear_user(addr, size);
	return size;
}

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

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

#else /* CONFIG_MMU */

/*
 * All the __XXX versions macros/functions below do not perform
 * access checking. It is assumed that the necessary checks have been
 * already performed before the finction (macro) is called.
 */

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

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

#define __get_user_asm(insn, __gu_ptr, __gu_val, __gu_err)		\
({									\
	__asm__ __volatile__ (						\
			"1:"	insn	" %1, %2, r0;			\
				addk	%0, r0, r0;			\
			2:						\
			.section .fixup,\"ax\";				\
			3:	brid	2b;				\
				addik	%0, r0, %3;			\
			.previous;					\
			.section __ex_table,\"a\";			\
			.word	1b,3b;					\
			.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;							\
})

#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:					\
		.section .fixup,\"ax\";			\
		4:	brid	3b;			\
			addik	%0, r0, %3;		\
		.previous;				\
		.section __ex_table,\"a\";		\
		.word	1b,4b,2b,4b;			\
		.previous;"				\
	: "=&r"(__gu_err)				\
	: "r"(&__gu_val),				\
	"r"(__gu_ptr), "i"(-EFAULT)			\
	);						\
})

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

/* 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);
}

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

#define copy_to_user(to, from, n)					\
	(access_ok(VERIFY_WRITE, (to), (n)) ?				\
		__copy_tofrom_user((void __user *)(to),			\
			(__force const void __user *)(from), (n))	\
		: -EFAULT)

#define __copy_to_user(to, from, n)	copy_to_user((to), (from), (n))
#define __copy_to_user_inatomic(to, from, n)	copy_to_user((to), (from), (n))

#define copy_from_user(to, from, n)					\
	(access_ok(VERIFY_READ, (from), (n)) ?				\
		__copy_tofrom_user((__force void __user *)(to),		\
			(void __user *)(from), (n))			\
		: -EFAULT)

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

#define strncpy_from_user(to, from, len)	\
		(access_ok(VERIFY_READ, from, 1) ?	\
			__strncpy_user(to, from, len) : -EFAULT)
#define strnlen_user(str, len)	\
		(access_ok(VERIFY_READ, str, 1) ? __strnlen_user(str, len) : 0)

#endif /* CONFIG_MMU */

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

#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
0d6de953 MS	74	#ifndef CONFIG_MMU
0d6de953 MS	75
60a729f7 MS	76	/* Check against bounds of physical memory */
	77	static inline int ___range_ok(unsigned long addr, unsigned long size)
	78	{
	79	return ((addr < memory_start) \|\|
	80	((addr + size) > memory_end));
	81	}
2660663f MS	82
	83	#define __range_ok(addr, size) \
	84	___range_ok((unsigned long)(addr), (unsigned long)(size))
	85
	86	#define access_ok(type, addr, size) (__range_ok((addr), (size)) == 0)
40b1156d MS	87
	88	#else
	89
	90	/*
	91	* Address is valid if:
	92	* - "addr", "addr + size" and "size" are all below the limit
	93	*/
	94	#define access_ok(type, addr, size) \
	95	(get_fs().seg > (((unsigned long)(addr)) \| \
	96	(size) \| ((unsigned long)(addr) + (size))))
	97
	98	/* \|\| printk("access_ok failed for %s at 0x%08lx (size %d), seg 0x%08x\n",
	99	type?"WRITE":"READ",addr,size,get_fs().seg)) */
	100
	101	#endif
	102
	103	#ifdef CONFIG_MMU
	104	# define __FIXUP_SECTION ".section .fixup,\"ax\"\n"
	105	# define __EX_TABLE_SECTION ".section __ex_table,\"a\"\n"
	106	#else
	107	# define __FIXUP_SECTION ".section .discard,\"ax\"\n"
	108	# define __EX_TABLE_SECTION ".section .discard,\"a\"\n"
	109	#endif
	110
	111	#ifndef CONFIG_MMU
2660663f	112
838d2406 AB	113	/* Undefined function to trigger linker error */
	114	extern int bad_user_access_length(void);
	115
2660663f	116	/* FIXME this is function for optimalization -> memcpy */
0d6de953 MS	117	#define __get_user(var, ptr) \
	118	({ \
	119	int __gu_err = 0; \
	120	switch (sizeof(*(ptr))) { \
	121	case 1: \
	122	case 2: \
	123	case 4: \
	124	(var) = *(ptr); \
	125	break; \
	126	case 8: \
	127	memcpy((void *) &(var), (ptr), 8); \
	128	break; \
	129	default: \
	130	(var) = 0; \
	131	__gu_err = __get_user_bad(); \
	132	break; \
	133	} \
	134	__gu_err; \
	135	})
2660663f MS	136
	137	#define __get_user_bad() (bad_user_access_length(), (-EFAULT))
	138
0d6de953	139	/* FIXME is not there defined __pu_val */
2660663f	140	#define __put_user(var, ptr) \
0d6de953 MS	141	({ \
	142	int __pu_err = 0; \
	143	switch (sizeof(*(ptr))) { \
	144	case 1: \
	145	case 2: \
	146	case 4: \
	147	*(ptr) = (var); \
	148	break; \
	149	case 8: { \
	150	typeof(*(ptr)) __pu_val = (var); \
	151	memcpy(ptr, &__pu_val, sizeof(__pu_val)); \
	152	} \
	153	break; \
	154	default: \
	155	__pu_err = __put_user_bad(); \
	156	break; \
	157	} \
	158	__pu_err; \
	159	})
2660663f MS	160
	161	#define __put_user_bad() (bad_user_access_length(), (-EFAULT))
	162
0d6de953 MS	163	#define put_user(x, ptr) __put_user((x), (ptr))
0d6de953 MS	164	#define get_user(x, ptr) __get_user((x), (ptr))
2660663f	165
0d6de953 MS	166	#define copy_to_user(to, from, n) (memcpy((to), (from), (n)), 0)
0d6de953 MS	167	#define copy_from_user(to, from, n) (memcpy((to), (from), (n)), 0)
2660663f	168
0d6de953 MS	169	#define __copy_to_user(to, from, n) (copy_to_user((to), (from), (n)))
	170	#define __copy_from_user(to, from, n) (copy_from_user((to), (from), (n)))
	171	#define __copy_to_user_inatomic(to, from, n) \
	172	(__copy_to_user((to), (from), (n)))
	173	#define __copy_from_user_inatomic(to, from, n) \
	174	(__copy_from_user((to), (from), (n)))
2660663f	175
40b1156d MS	176	#define __clear_user(addr, n) (memset((void *)(addr), 0, (n)), 0)
	177
	178	/* stejne s MMU */
2660663f MS	179	static inline unsigned long clear_user(void *addr, unsigned long size)
	180	{
	181	if (access_ok(VERIFY_WRITE, addr, size))
	182	size = __clear_user(addr, size);
	183	return size;
	184	}
	185
0d6de953	186	/* Returns 0 if exception not found and fixup otherwise. */
2660663f MS	187	extern unsigned long search_exception_table(unsigned long);
2660663f MS	188
0d6de953 MS	189	extern long strncpy_from_user(char dst, const char src, long count);
	190	extern long strnlen_user(const char *src, long count);
	191
	192	#else /* CONFIG_MMU */
	193
0d6de953 MS	194	/*
	195	* All the __XXX versions macros/functions below do not perform
	196	* access checking. It is assumed that the necessary checks have been
	197	* already performed before the finction (macro) is called.
	198	*/
	199
	200	#define get_user(x, ptr) \
	201	({ \
	202	access_ok(VERIFY_READ, (ptr), sizeof(*(ptr))) \
	203	? __get_user((x), (ptr)) : -EFAULT; \
	204	})
	205
	206	#define put_user(x, ptr) \
	207	({ \
	208	access_ok(VERIFY_WRITE, (ptr), sizeof(*(ptr))) \
	209	? __put_user((x), (ptr)) : -EFAULT; \
	210	})
	211
	212	#define __get_user(x, ptr) \
	213	({ \
	214	unsigned long __gu_val; \
	215	/unsigned long __gu_ptr = (unsigned long)(ptr);/ \
	216	long __gu_err; \
	217	switch (sizeof(*(ptr))) { \
	218	case 1: \
	219	__get_user_asm("lbu", (ptr), __gu_val, __gu_err); \
	220	break; \
	221	case 2: \
	222	__get_user_asm("lhu", (ptr), __gu_val, __gu_err); \
	223	break; \
	224	case 4: \
	225	__get_user_asm("lw", (ptr), __gu_val, __gu_err); \
	226	break; \
	227	default: \
	228	__gu_val = 0; __gu_err = -EINVAL; \
	229	} \
	230	x = (__typeof__(*(ptr))) __gu_val; \
	231	__gu_err; \
	232	})
	233
	234	#define __get_user_asm(insn, __gu_ptr, __gu_val, __gu_err) \
	235	({ \
	236	__asm__ __volatile__ ( \
	237	"1:" insn " %1, %2, r0; \
	238	addk %0, r0, r0; \
	239	2: \
	240	.section .fixup,\"ax\"; \
	241	3: brid 2b; \
	242	addik %0, r0, %3; \
	243	.previous; \
	244	.section __ex_table,\"a\"; \
	245	.word 1b,3b; \
	246	.previous;" \
	247	: "=r"(__gu_err), "=r"(__gu_val) \
	248	: "r"(__gu_ptr), "i"(-EFAULT) \
	249	); \
	250	})
	251
	252	#define __put_user(x, ptr) \
	253	({ \
7bcb63b2	254	__typeof__(*(ptr)) volatile __gu_val = (x); \
0d6de953 MS	255	long __gu_err = 0; \
	256	switch (sizeof(__gu_val)) { \
	257	case 1: \
	258	__put_user_asm("sb", (ptr), __gu_val, __gu_err); \
	259	break; \
	260	case 2: \
	261	__put_user_asm("sh", (ptr), __gu_val, __gu_err); \
	262	break; \
	263	case 4: \
	264	__put_user_asm("sw", (ptr), __gu_val, __gu_err); \
	265	break; \
	266	case 8: \
	267	__put_user_asm_8((ptr), __gu_val, __gu_err); \
	268	break; \
	269	default: \
	270	__gu_err = -EINVAL; \
	271	} \
	272	__gu_err; \
	273	})
	274
	275	#define __put_user_asm_8(__gu_ptr, __gu_val, __gu_err) \
	276	({ \
	277	__asm__ __volatile__ (" lwi %0, %1, 0; \
	278	1: swi %0, %2, 0; \
	279	lwi %0, %1, 4; \
	280	2: swi %0, %2, 4; \
	281	addk %0,r0,r0; \
	282	3: \
	283	.section .fixup,\"ax\"; \
	284	4: brid 3b; \
	285	addik %0, r0, %3; \
	286	.previous; \
	287	.section __ex_table,\"a\"; \
	288	.word 1b,4b,2b,4b; \
	289	.previous;" \
	290	: "=&r"(__gu_err) \
	291	: "r"(&__gu_val), \
	292	"r"(__gu_ptr), "i"(-EFAULT) \
	293	); \
	294	})
	295
	296	#define __put_user_asm(insn, __gu_ptr, __gu_val, __gu_err) \
	297	({ \
	298	__asm__ __volatile__ ( \
	299	"1:" insn " %1, %2, r0; \
	300	addk %0, r0, r0; \
	301	2: \
	302	.section .fixup,\"ax\"; \
	303	3: brid 2b; \
	304	addik %0, r0, %3; \
	305	.previous; \
	306	.section __ex_table,\"a\"; \
	307	.word 1b,3b; \
	308	.previous;" \
	309	: "=r"(__gu_err) \
	310	: "r"(__gu_val), "r"(__gu_ptr), "i"(-EFAULT) \
	311	); \
	312	})
	313
40b1156d MS	314	/* Return: number of not copied bytes, i.e. 0 if OK or non-zero if fail. */
	315	static inline unsigned long __must_check __clear_user(void __user *to,
	316	unsigned long n)
0d6de953	317	{
40b1156d MS	318	/* normal memset with two words to __ex_table */
	319	__asm__ __volatile__ ( \
	320	"1: sb r0, %2, r0;" \
	321	" addik %0, %0, -1;" \
	322	" bneid %0, 1b;" \
	323	" addik %2, %2, 1;" \
	324	"2: " \
	325	__EX_TABLE_SECTION \
	326	".word 1b,2b;" \
	327	".previous;" \
	328	: "=r"(n) \
	329	: "0"(n), "r"(to)
	330	);
	331	return n;
	332	}
	333
	334	static inline unsigned long __must_check clear_user(void __user *to,
	335	unsigned long n)
	336	{
	337	might_sleep();
	338	if (unlikely(!access_ok(VERIFY_WRITE, to, n)))
	339	return n;
	340
	341	return __clear_user(to, n);
0d6de953 MS	342	}
0d6de953 MS	343
95dfbbe4 JW	344	#define __copy_from_user(to, from, n) copy_from_user((to), (from), (n))
	345	#define __copy_from_user_inatomic(to, from, n) \
	346	copy_from_user((to), (from), (n))
0d6de953 MS	347
	348	#define copy_to_user(to, from, n) \
	349	(access_ok(VERIFY_WRITE, (to), (n)) ? \
	350	__copy_tofrom_user((void __user *)(to), \
	351	(__force const void __user *)(from), (n)) \
	352	: -EFAULT)
	353
	354	#define __copy_to_user(to, from, n) copy_to_user((to), (from), (n))
	355	#define __copy_to_user_inatomic(to, from, n) copy_to_user((to), (from), (n))
	356
	357	#define copy_from_user(to, from, n) \
	358	(access_ok(VERIFY_READ, (from), (n)) ? \
	359	__copy_tofrom_user((__force void __user *)(to), \
	360	(void __user *)(from), (n)) \
	361	: -EFAULT)
	362
0d6de953 MS	363	extern int __strncpy_user(char to, const char __user from, int len);
	364	extern int __strnlen_user(const char __user *sstr, int len);
	365
	366	#define strncpy_from_user(to, from, len) \
	367	(access_ok(VERIFY_READ, from, 1) ? \
	368	__strncpy_user(to, from, len) : -EFAULT)
	369	#define strnlen_user(str, len) \
	370	(access_ok(VERIFY_READ, str, 1) ? __strnlen_user(str, len) : 0)
2660663f	371
0d6de953	372	#endif /* CONFIG_MMU */
2660663f	373
95dfbbe4 JW	374	extern unsigned long __copy_tofrom_user(void __user *to,
	375	const void __user *from, unsigned long size);
	376
2660663f MS	377	#endif /* __ASSEMBLY__ */
	378	#endif /* __KERNEL__ */
	379
	380	#endif /* _ASM_MICROBLAZE_UACCESS_H */