[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 */

/* 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);
}

/* 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;			\
})

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

#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)	\
	__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;
}

#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 */


#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
0dcb409d MS	194	/* Return: number of not copied bytes, i.e. 0 if OK or non-zero if fail. */
	195	static inline unsigned long __must_check __clear_user(void __user *to,
	196	unsigned long n)
	197	{
	198	/* normal memset with two words to __ex_table */
	199	__asm__ __volatile__ ( \
	200	"1: sb r0, %2, r0;" \
	201	" addik %0, %0, -1;" \
	202	" bneid %0, 1b;" \
	203	" addik %2, %2, 1;" \
	204	"2: " \
	205	__EX_TABLE_SECTION \
	206	".word 1b,2b;" \
	207	".previous;" \
	208	: "=r"(n) \
	209	: "0"(n), "r"(to)
	210	);
	211	return n;
	212	}
	213
	214	static inline unsigned long __must_check clear_user(void __user *to,
	215	unsigned long n)
	216	{
	217	might_sleep();
	218	if (unlikely(!access_ok(VERIFY_WRITE, to, n)))
	219	return n;
	220	return __clear_user(to, n);
	221	}
	222
	223	/* put_user and get_user macros */
	224
	225	extern long __user_bad(void);
0d6de953	226
8b651aa4 MS	227	#define __get_user_asm(insn, __gu_ptr, __gu_val, __gu_err) \
	228	({ \
	229	__asm__ __volatile__ ( \
	230	"1:" insn " %1, %2, r0;" \
	231	" addk %0, r0, r0;" \
	232	"2: " \
	233	__FIXUP_SECTION \
	234	"3: brid 2b; " \
	235	" addik %0, r0, %3;" \
	236	".previous;" \
	237	__EX_TABLE_SECTION \
	238	".word 1b,3b;" \
	239	".previous;" \
	240	: "=&r"(__gu_err), "=r"(__gu_val) \
	241	: "r"(__gu_ptr), "i"(-EFAULT) \
	242	); \
0d6de953 MS	243	})
	244
	245	#define __get_user(x, ptr) \
	246	({ \
	247	unsigned long __gu_val; \
	248	/unsigned long __gu_ptr = (unsigned long)(ptr);/ \
	249	long __gu_err; \
	250	switch (sizeof(*(ptr))) { \
	251	case 1: \
	252	__get_user_asm("lbu", (ptr), __gu_val, __gu_err); \
	253	break; \
	254	case 2: \
	255	__get_user_asm("lhu", (ptr), __gu_val, __gu_err); \
	256	break; \
	257	case 4: \
	258	__get_user_asm("lw", (ptr), __gu_val, __gu_err); \
	259	break; \
	260	default: \
0dcb409d	261	/* __gu_val = 0; __gu_err = -EINVAL;*/ __gu_err = __user_bad();\
0d6de953 MS	262	} \
	263	x = (__typeof__(*(ptr))) __gu_val; \
	264	__gu_err; \
	265	})
	266
0dcb409d MS	267	/**
	268	* get_user: - Get a simple variable from user space.
	269	* @x: Variable to store result.
	270	* @ptr: Source address, in user space.
	271	*
	272	* Context: User context only. This function may sleep.
	273	*
	274	* This macro copies a single simple variable from user space to kernel
	275	* space. It supports simple types like char and int, but not larger
	276	* data types like structures or arrays.
	277	*
	278	* @ptr must have pointer-to-simple-variable type, and the result of
	279	* dereferencing @ptr must be assignable to @x without a cast.
	280	*
	281	* Returns zero on success, or -EFAULT on error.
	282	* On error, the variable @x is set to zero.
	283	*/
	284
8b651aa4 MS	285	#define get_user(x, ptr) \
	286	({ \
	287	access_ok(VERIFY_READ, (ptr), sizeof(*(ptr))) \
	288	? __get_user((x), (ptr)) : -EFAULT; \
	289	})
	290
0dcb409d MS	291	/**
	292	* put_user: - Write a simple value into user space.
	293	* @x: Value to copy to user space.
	294	* @ptr: Destination address, in user space.
	295	*
	296	* Context: User context only. This function may sleep.
	297	*
	298	* This macro copies a single simple value from kernel space to user
	299	* space. It supports simple types like char and int, but not larger
	300	* data types like structures or arrays.
	301	*
	302	* @ptr must have pointer-to-simple-variable type, and @x must be assignable
	303	* to the result of dereferencing @ptr.
	304	*
	305	* Returns zero on success, or -EFAULT on error.
	306	*/
	307
8b651aa4	308	#define __put_user_asm(insn, __gu_ptr, __gu_val, __gu_err) \
c77a9c4b MS	309	({ \
	310	__asm__ __volatile__ ( \
	311	"1:" insn " %1, %2, r0;" \
	312	" addk %0, r0, r0;" \
	313	"2: " \
	314	__FIXUP_SECTION \
8b651aa4	315	"3: brid 2b;" \
c77a9c4b MS	316	" addik %0, r0, %3;" \
	317	".previous;" \
	318	__EX_TABLE_SECTION \
	319	".word 1b,3b;" \
	320	".previous;" \
8b651aa4 MS	321	: "=&r"(__gu_err) \
8b651aa4 MS	322	: "r"(__gu_val), "r"(__gu_ptr), "i"(-EFAULT) \
c77a9c4b	323	); \
0d6de953 MS	324	})
0d6de953 MS	325
8b651aa4 MS	326	#define __put_user_asm_8(__gu_ptr, __gu_val, __gu_err) \
	327	({ \
	328	__asm__ __volatile__ (" lwi %0, %1, 0;" \
	329	"1: swi %0, %2, 0;" \
	330	" lwi %0, %1, 4;" \
	331	"2: swi %0, %2, 4;" \
	332	" addk %0, r0, r0;" \
	333	"3: " \
	334	__FIXUP_SECTION \
	335	"4: brid 3b;" \
	336	" addik %0, r0, %3;" \
	337	".previous;" \
	338	__EX_TABLE_SECTION \
	339	".word 1b,4b,2b,4b;" \
	340	".previous;" \
	341	: "=&r"(__gu_err) \
	342	: "r"(&__gu_val), "r"(__gu_ptr), "i"(-EFAULT) \
	343	); \
	344	})
c77a9c4b	345
0d6de953 MS	346	#define __put_user(x, ptr) \
0d6de953 MS	347	({ \
7bcb63b2	348	__typeof__(*(ptr)) volatile __gu_val = (x); \
0d6de953 MS	349	long __gu_err = 0; \
	350	switch (sizeof(__gu_val)) { \
	351	case 1: \
	352	__put_user_asm("sb", (ptr), __gu_val, __gu_err); \
	353	break; \
	354	case 2: \
	355	__put_user_asm("sh", (ptr), __gu_val, __gu_err); \
	356	break; \
	357	case 4: \
	358	__put_user_asm("sw", (ptr), __gu_val, __gu_err); \
	359	break; \
	360	case 8: \
	361	__put_user_asm_8((ptr), __gu_val, __gu_err); \
	362	break; \
	363	default: \
0dcb409d	364	/__gu_err = -EINVAL;/ __gu_err = __user_bad(); \
0d6de953 MS	365	} \
	366	__gu_err; \
	367	})
	368
8b651aa4 MS	369	#define put_user(x, ptr) \
	370	({ \
	371	access_ok(VERIFY_WRITE, (ptr), sizeof(*(ptr))) \
	372	? __put_user((x), (ptr)) : -EFAULT; \
0d6de953 MS	373	})
0d6de953 MS	374
cc5a428b MS	375	extern unsigned long __copy_tofrom_user(void __user *to,
	376	const void __user *from, unsigned long size);
	377
95dfbbe4 JW	378	#define __copy_from_user(to, from, n) copy_from_user((to), (from), (n))
	379	#define __copy_from_user_inatomic(to, from, n) \
	380	copy_from_user((to), (from), (n))
0d6de953	381
cc5a428b MS	382	#define __copy_to_user(to, from, n) \
	383	__copy_tofrom_user((void __user *)(to), \
	384	(__force const void __user *)(from), (n))
0d6de953 MS	385	#define __copy_to_user_inatomic(to, from, n) copy_to_user((to), (from), (n))
0d6de953 MS	386
cc5a428b MS	387	static inline long copy_to_user(void __user *to,
	388	const void *from, unsigned long n)
	389	{
	390	might_sleep();
	391	if (access_ok(VERIFY_WRITE, to, n))
	392	return __copy_to_user(to, from, n);
	393	else
	394	return n;
	395	}
	396
0d6de953 MS	397	#define copy_from_user(to, from, n) \
	398	(access_ok(VERIFY_READ, (from), (n)) ? \
	399	__copy_tofrom_user((__force void __user *)(to), \
	400	(void __user *)(from), (n)) \
	401	: -EFAULT)
	402
0d6de953 MS	403	extern int __strncpy_user(char to, const char __user from, int len);
	404	extern int __strnlen_user(const char __user *sstr, int len);
	405
	406	#define strncpy_from_user(to, from, len) \
	407	(access_ok(VERIFY_READ, from, 1) ? \
	408	__strncpy_user(to, from, len) : -EFAULT)
	409	#define strnlen_user(str, len) \
	410	(access_ok(VERIFY_READ, str, 1) ? __strnlen_user(str, len) : 0)
2660663f	411
0d6de953	412	#endif /* CONFIG_MMU */
2660663f	413
95dfbbe4	414
2660663f MS	415	#endif /* __ASSEMBLY__ */
	416	#endif /* __KERNEL__ */
	417
	418	#endif /* _ASM_MICROBLAZE_UACCESS_H */