[mirror_ubuntu-artful-kernel.git] / include / asm-x86_64 / uaccess.h

#ifndef __X86_64_UACCESS_H
#define __X86_64_UACCESS_H

/*
 * User space memory access functions
 */
#include <linux/compiler.h>
#include <linux/errno.h>
#include <linux/prefetch.h>
#include <asm/page.h>

#define VERIFY_READ 0
#define VERIFY_WRITE 1

/*
 * 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.
 */

#define MAKE_MM_SEG(s)	((mm_segment_t) { (s) })

#define KERNEL_DS	MAKE_MM_SEG(0xFFFFFFFFFFFFFFFFUL)
#define USER_DS		MAKE_MM_SEG(PAGE_OFFSET)

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

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

#define __addr_ok(addr) (!((unsigned long)(addr) & (current_thread_info()->addr_limit.seg)))

/*
 * Uhhuh, this needs 65-bit arithmetic. We have a carry..
 */
#define __range_not_ok(addr,size) ({ \
	unsigned long flag,roksum; \
	__chk_user_ptr(addr); \
	asm("# range_ok\n\r" \
		"addq %3,%1 ; sbbq %0,%0 ; cmpq %1,%4 ; sbbq $0,%0"  \
		:"=&r" (flag), "=r" (roksum) \
		:"1" (addr),"g" ((long)(size)),"g" (current_thread_info()->addr_limit.seg)); \
	flag; })

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

/*
 * 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;
};

#define ARCH_HAS_SEARCH_EXTABLE

/*
 * These are the main single-value transfer routines.  They automatically
 * use the right size if we just have the right pointer type.
 *
 * This gets kind of ugly. We want to return _two_ values in "get_user()"
 * and yet we don't want to do any pointers, because that is too much
 * of a performance impact. Thus we have a few rather ugly macros here,
 * and hide all the ugliness from the user.
 *
 * The "__xxx" versions of the user access functions are versions that
 * do not verify the address space, that must have been done previously
 * with a separate "access_ok()" call (this is used when we do multiple
 * accesses to the same area of user memory).
 */

#define __get_user_x(size,ret,x,ptr) \
	asm volatile("call __get_user_" #size \
		:"=a" (ret),"=d" (x) \
		:"c" (ptr) \
		:"r8")

/* Careful: we have to cast the result to the type of the pointer for sign reasons */
#define get_user(x,ptr)							\
({	unsigned long __val_gu;						\
	int __ret_gu; 							\
	__chk_user_ptr(ptr);						\
	switch(sizeof (*(ptr))) {					\
	case 1:  __get_user_x(1,__ret_gu,__val_gu,ptr); break;		\
	case 2:  __get_user_x(2,__ret_gu,__val_gu,ptr); break;		\
	case 4:  __get_user_x(4,__ret_gu,__val_gu,ptr); break;		\
	case 8:  __get_user_x(8,__ret_gu,__val_gu,ptr); break;		\
	default: __get_user_bad(); break;				\
	}								\
	(x) = (typeof(*(ptr)))__val_gu;				\
	__ret_gu;							\
})

extern void __put_user_1(void);
extern void __put_user_2(void);
extern void __put_user_4(void);
extern void __put_user_8(void);
extern void __put_user_bad(void);

#define __put_user_x(size,ret,x,ptr)					\
	asm volatile("call __put_user_" #size			\
		:"=a" (ret)						\
		:"c" (ptr),"d" (x)					\
		:"r8")

#define put_user(x,ptr)							\
  __put_user_check((__typeof__(*(ptr)))(x),(ptr),sizeof(*(ptr)))

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

#define __get_user_unaligned __get_user
#define __put_user_unaligned __put_user

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


#define __put_user_check(x,ptr,size)			\
({							\
	int __pu_err;					\
	typeof(*(ptr)) __user *__pu_addr = (ptr);	\
	switch (size) { 				\
	case 1: __put_user_x(1,__pu_err,x,__pu_addr); break;	\
	case 2: __put_user_x(2,__pu_err,x,__pu_addr); break;	\
	case 4: __put_user_x(4,__pu_err,x,__pu_addr); break;	\
	case 8: __put_user_x(8,__pu_err,x,__pu_addr); break;	\
	default: __put_user_bad();			\
	}						\
	__pu_err;					\
})

#define __put_user_size(x,ptr,size,retval)				\
do {									\
	retval = 0;							\
	__chk_user_ptr(ptr);						\
	switch (size) {							\
	  case 1: __put_user_asm(x,ptr,retval,"b","b","iq",-EFAULT); break;\
	  case 2: __put_user_asm(x,ptr,retval,"w","w","ir",-EFAULT); break;\
	  case 4: __put_user_asm(x,ptr,retval,"l","k","ir",-EFAULT); break;\
	  case 8: __put_user_asm(x,ptr,retval,"q","","Zr",-EFAULT); break;\
	  default: __put_user_bad();					\
	}								\
} while (0)

/* FIXME: this hack is definitely wrong -AK */
struct __large_struct { unsigned long buf[100]; };
#define __m(x) (*(struct __large_struct __user *)(x))

/*
 * Tell gcc we read from memory instead of writing: this is because
 * we do not write to any memory gcc knows about, so there are no
 * aliasing issues.
 */
#define __put_user_asm(x, addr, err, itype, rtype, ltype, errno)	\
	asm volatile(					\
		"1:	mov"itype" %"rtype"1,%2\n"		\
		"2:\n"						\
		".section .fixup,\"ax\"\n"			\
		"3:	mov %3,%0\n"				\
		"	jmp 2b\n"				\
		".previous\n"					\
		".section __ex_table,\"a\"\n"			\
		"	.align 8\n"				\
		"	.quad 1b,3b\n"				\
		".previous"					\
		: "=r"(err)					\
		: ltype (x), "m"(__m(addr)), "i"(errno), "0"(err))


#define __get_user_nocheck(x,ptr,size)				\
({								\
	int __gu_err;						\
	unsigned long __gu_val;					\
	__get_user_size(__gu_val,(ptr),(size),__gu_err);	\
	(x) = (typeof(*(ptr)))__gu_val;			\
	__gu_err;						\
})

extern int __get_user_1(void);
extern int __get_user_2(void);
extern int __get_user_4(void);
extern int __get_user_8(void);
extern int __get_user_bad(void);

#define __get_user_size(x,ptr,size,retval)				\
do {									\
	retval = 0;							\
	__chk_user_ptr(ptr);						\
	switch (size) {							\
	  case 1: __get_user_asm(x,ptr,retval,"b","b","=q",-EFAULT); break;\
	  case 2: __get_user_asm(x,ptr,retval,"w","w","=r",-EFAULT); break;\
	  case 4: __get_user_asm(x,ptr,retval,"l","k","=r",-EFAULT); break;\
	  case 8: __get_user_asm(x,ptr,retval,"q","","=r",-EFAULT); break;\
	  default: (x) = __get_user_bad();				\
	}								\
} while (0)

#define __get_user_asm(x, addr, err, itype, rtype, ltype, errno)	\
	asm volatile(					\
		"1:	mov"itype" %2,%"rtype"1\n"		\
		"2:\n"						\
		".section .fixup,\"ax\"\n"			\
		"3:	mov %3,%0\n"				\
		"	xor"itype" %"rtype"1,%"rtype"1\n"	\
		"	jmp 2b\n"				\
		".previous\n"					\
		".section __ex_table,\"a\"\n"			\
		"	.align 8\n"				\
		"	.quad 1b,3b\n"				\
		".previous"					\
		: "=r"(err), ltype (x)				\
		: "m"(__m(addr)), "i"(errno), "0"(err))

/*
 * Copy To/From Userspace
 */

/* Handles exceptions in both to and from, but doesn't do access_ok */
__must_check unsigned long
copy_user_generic(void *to, const void *from, unsigned len);

__must_check unsigned long
copy_to_user(void __user *to, const void *from, unsigned len);
__must_check unsigned long
copy_from_user(void *to, const void __user *from, unsigned len);
__must_check unsigned long
copy_in_user(void __user *to, const void __user *from, unsigned len);

static __always_inline __must_check
int __copy_from_user(void *dst, const void __user *src, unsigned size)
{ 
	int ret = 0;
	if (!__builtin_constant_p(size))
		return copy_user_generic(dst,(__force void *)src,size);
	switch (size) { 
	case 1:__get_user_asm(*(u8*)dst,(u8 __user *)src,ret,"b","b","=q",1); 
		return ret;
	case 2:__get_user_asm(*(u16*)dst,(u16 __user *)src,ret,"w","w","=r",2);
		return ret;
	case 4:__get_user_asm(*(u32*)dst,(u32 __user *)src,ret,"l","k","=r",4);
		return ret;
	case 8:__get_user_asm(*(u64*)dst,(u64 __user *)src,ret,"q","","=r",8);
		return ret; 
	case 10:
	       	__get_user_asm(*(u64*)dst,(u64 __user *)src,ret,"q","","=r",16);
		if (unlikely(ret)) return ret;
		__get_user_asm(*(u16*)(8+(char*)dst),(u16 __user *)(8+(char __user *)src),ret,"w","w","=r",2);
		return ret; 
	case 16:
		__get_user_asm(*(u64*)dst,(u64 __user *)src,ret,"q","","=r",16);
		if (unlikely(ret)) return ret;
		__get_user_asm(*(u64*)(8+(char*)dst),(u64 __user *)(8+(char __user *)src),ret,"q","","=r",8);
		return ret; 
	default:
		return copy_user_generic(dst,(__force void *)src,size); 
	}
}	

static __always_inline __must_check
int __copy_to_user(void __user *dst, const void *src, unsigned size)
{ 
	int ret = 0;
	if (!__builtin_constant_p(size))
		return copy_user_generic((__force void *)dst,src,size);
	switch (size) { 
	case 1:__put_user_asm(*(u8*)src,(u8 __user *)dst,ret,"b","b","iq",1); 
		return ret;
	case 2:__put_user_asm(*(u16*)src,(u16 __user *)dst,ret,"w","w","ir",2);
		return ret;
	case 4:__put_user_asm(*(u32*)src,(u32 __user *)dst,ret,"l","k","ir",4);
		return ret;
	case 8:__put_user_asm(*(u64*)src,(u64 __user *)dst,ret,"q","","ir",8);
		return ret; 
	case 10:
		__put_user_asm(*(u64*)src,(u64 __user *)dst,ret,"q","","ir",10);
		if (unlikely(ret)) return ret;
		asm("":::"memory");
		__put_user_asm(4[(u16*)src],4+(u16 __user *)dst,ret,"w","w","ir",2);
		return ret; 
	case 16:
		__put_user_asm(*(u64*)src,(u64 __user *)dst,ret,"q","","ir",16);
		if (unlikely(ret)) return ret;
		asm("":::"memory");
		__put_user_asm(1[(u64*)src],1+(u64 __user *)dst,ret,"q","","ir",8);
		return ret; 
	default:
		return copy_user_generic((__force void *)dst,src,size); 
	}
}	

static __always_inline __must_check
int __copy_in_user(void __user *dst, const void __user *src, unsigned size)
{ 
	int ret = 0;
	if (!__builtin_constant_p(size))
		return copy_user_generic((__force void *)dst,(__force void *)src,size);
	switch (size) { 
	case 1: { 
		u8 tmp;
		__get_user_asm(tmp,(u8 __user *)src,ret,"b","b","=q",1); 
		if (likely(!ret))
			__put_user_asm(tmp,(u8 __user *)dst,ret,"b","b","iq",1); 
		return ret;
	}
	case 2: { 
		u16 tmp;
		__get_user_asm(tmp,(u16 __user *)src,ret,"w","w","=r",2); 
		if (likely(!ret))
			__put_user_asm(tmp,(u16 __user *)dst,ret,"w","w","ir",2); 
		return ret;
	}

	case 4: { 
		u32 tmp;
		__get_user_asm(tmp,(u32 __user *)src,ret,"l","k","=r",4); 
		if (likely(!ret))
			__put_user_asm(tmp,(u32 __user *)dst,ret,"l","k","ir",4); 
		return ret;
	}
	case 8: { 
		u64 tmp;
		__get_user_asm(tmp,(u64 __user *)src,ret,"q","","=r",8); 
		if (likely(!ret))
			__put_user_asm(tmp,(u64 __user *)dst,ret,"q","","ir",8); 
		return ret;
	}
	default:
		return copy_user_generic((__force void *)dst,(__force void *)src,size); 
	}
}	

__must_check long 
strncpy_from_user(char *dst, const char __user *src, long count);
__must_check long 
__strncpy_from_user(char *dst, const char __user *src, long count);
__must_check long strnlen_user(const char __user *str, long n);
__must_check long __strnlen_user(const char __user *str, long n);
__must_check long strlen_user(const char __user *str);
__must_check unsigned long clear_user(void __user *mem, unsigned long len);
__must_check unsigned long __clear_user(void __user *mem, unsigned long len);

__must_check long __copy_from_user_inatomic(void *dst, const void __user *src, unsigned size);

static __must_check __always_inline int
__copy_to_user_inatomic(void __user *dst, const void *src, unsigned size)
{
	return copy_user_generic((__force void *)dst, src, size);
}

#define ARCH_HAS_NOCACHE_UACCESS 1
extern long __copy_user_nocache(void *dst, const void __user *src, unsigned size, int zerorest);

static inline int __copy_from_user_nocache(void *dst, const void __user *src, unsigned size)
{
	might_sleep();
	return __copy_user_nocache(dst, src, size, 1);
}

static inline int __copy_from_user_inatomic_nocache(void *dst, const void __user *src, unsigned size)
{
	return __copy_user_nocache(dst, src, size, 0);
}

#endif /* __X86_64_UACCESS_H */
Commit	Line	Data
1da177e4 LT	1	#ifndef __X86_64_UACCESS_H
	2	#define __X86_64_UACCESS_H
	3
	4	/*
	5	* User space memory access functions
	6	*/
1da177e4 LT	7	#include <linux/compiler.h>
1da177e4 LT	8	#include <linux/errno.h>
1da177e4 LT	9	#include <linux/prefetch.h>
	10	#include <asm/page.h>
	11
	12	#define VERIFY_READ 0
	13	#define VERIFY_WRITE 1
	14
	15	/*
	16	* The fs value determines whether argument validity checking should be
	17	* performed or not. If get_fs() == USER_DS, checking is performed, with
	18	* get_fs() == KERNEL_DS, checking is bypassed.
	19	*
	20	* For historical reasons, these macros are grossly misnamed.
	21	*/
	22
	23	#define MAKE_MM_SEG(s) ((mm_segment_t) { (s) })
	24
	25	#define KERNEL_DS MAKE_MM_SEG(0xFFFFFFFFFFFFFFFFUL)
	26	#define USER_DS MAKE_MM_SEG(PAGE_OFFSET)
	27
	28	#define get_ds() (KERNEL_DS)
	29	#define get_fs() (current_thread_info()->addr_limit)
	30	#define set_fs(x) (current_thread_info()->addr_limit = (x))
	31
	32	#define segment_eq(a,b) ((a).seg == (b).seg)
	33
	34	#define __addr_ok(addr) (!((unsigned long)(addr) & (current_thread_info()->addr_limit.seg)))
	35
	36	/*
	37	* Uhhuh, this needs 65-bit arithmetic. We have a carry..
	38	*/
	39	#define __range_not_ok(addr,size) ({ \
16cf5b39	40	unsigned long flag,roksum; \
1da177e4 LT	41	__chk_user_ptr(addr); \
	42	asm("# range_ok\n\r" \
	43	"addq %3,%1 ; sbbq %0,%0 ; cmpq %1,%4 ; sbbq $0,%0" \
16cf5b39	44	:"=&r" (flag), "=r" (roksum) \
1da177e4 LT	45	:"1" (addr),"g" ((long)(size)),"g" (current_thread_info()->addr_limit.seg)); \
	46	flag; })
	47
	48	#define access_ok(type, addr, size) (__range_not_ok(addr,size) == 0)
	49
1da177e4 LT	50	/*
	51	* The exception table consists of pairs of addresses: the first is the
	52	* address of an instruction that is allowed to fault, and the second is
	53	* the address at which the program should continue. No registers are
	54	* modified, so it is entirely up to the continuation code to figure out
	55	* what to do.
	56	*
	57	* All the routines below use bits of fixup code that are out of line
	58	* with the main instruction path. This means when everything is well,
	59	* we don't even have to jump over them. Further, they do not intrude
	60	* on our cache or tlb entries.
	61	*/
	62
	63	struct exception_table_entry
	64	{
	65	unsigned long insn, fixup;
	66	};
	67
	68	#define ARCH_HAS_SEARCH_EXTABLE
	69
	70	/*
	71	* These are the main single-value transfer routines. They automatically
	72	* use the right size if we just have the right pointer type.
	73	*
	74	* This gets kind of ugly. We want to return _two_ values in "get_user()"
	75	* and yet we don't want to do any pointers, because that is too much
	76	* of a performance impact. Thus we have a few rather ugly macros here,
	77	* and hide all the ugliness from the user.
	78	*
	79	* The "__xxx" versions of the user access functions are versions that
	80	* do not verify the address space, that must have been done previously
	81	* with a separate "access_ok()" call (this is used when we do multiple
	82	* accesses to the same area of user memory).
	83	*/
	84
	85	#define __get_user_x(size,ret,x,ptr) \
383d079b	86	asm volatile("call __get_user_" #size \
1da177e4 LT	87	:"=a" (ret),"=d" (x) \
	88	:"c" (ptr) \
	89	:"r8")
	90
	91	/* Careful: we have to cast the result to the type of the pointer for sign reasons */
	92	#define get_user(x,ptr) \
	93	({ unsigned long __val_gu; \
	94	int __ret_gu; \
	95	__chk_user_ptr(ptr); \
	96	switch(sizeof (*(ptr))) { \
	97	case 1: __get_user_x(1,__ret_gu,__val_gu,ptr); break; \
	98	case 2: __get_user_x(2,__ret_gu,__val_gu,ptr); break; \
	99	case 4: __get_user_x(4,__ret_gu,__val_gu,ptr); break; \
	100	case 8: __get_user_x(8,__ret_gu,__val_gu,ptr); break; \
	101	default: __get_user_bad(); break; \
	102	} \
383d079b	103	(x) = (typeof(*(ptr)))__val_gu; \
1da177e4 LT	104	__ret_gu; \
	105	})
	106
	107	extern void __put_user_1(void);
	108	extern void __put_user_2(void);
	109	extern void __put_user_4(void);
	110	extern void __put_user_8(void);
	111	extern void __put_user_bad(void);
	112
	113	#define __put_user_x(size,ret,x,ptr) \
383d079b	114	asm volatile("call __put_user_" #size \
1da177e4 LT	115	:"=a" (ret) \
	116	:"c" (ptr),"d" (x) \
	117	:"r8")
	118
	119	#define put_user(x,ptr) \
	120	__put_user_check((__typeof__((ptr)))(x),(ptr),sizeof((ptr)))
	121
	122	#define __get_user(x,ptr) \
	123	__get_user_nocheck((x),(ptr),sizeof(*(ptr)))
	124	#define __put_user(x,ptr) \
	125	__put_user_nocheck((__typeof__((ptr)))(x),(ptr),sizeof((ptr)))
	126
	127	#define __get_user_unaligned __get_user
	128	#define __put_user_unaligned __put_user
	129
	130	#define __put_user_nocheck(x,ptr,size) \
	131	({ \
	132	int __pu_err; \
	133	__put_user_size((x),(ptr),(size),__pu_err); \
	134	__pu_err; \
	135	})
	136
	137
	138	#define __put_user_check(x,ptr,size) \
	139	({ \
	140	int __pu_err; \
383d079b	141	typeof((ptr)) __user __pu_addr = (ptr); \
1da177e4 LT	142	switch (size) { \
	143	case 1: __put_user_x(1,__pu_err,x,__pu_addr); break; \
	144	case 2: __put_user_x(2,__pu_err,x,__pu_addr); break; \
	145	case 4: __put_user_x(4,__pu_err,x,__pu_addr); break; \
	146	case 8: __put_user_x(8,__pu_err,x,__pu_addr); break; \
	147	default: __put_user_bad(); \
	148	} \
	149	__pu_err; \
	150	})
	151
	152	#define __put_user_size(x,ptr,size,retval) \
	153	do { \
	154	retval = 0; \
	155	__chk_user_ptr(ptr); \
	156	switch (size) { \
	157	case 1: __put_user_asm(x,ptr,retval,"b","b","iq",-EFAULT); break;\
	158	case 2: __put_user_asm(x,ptr,retval,"w","w","ir",-EFAULT); break;\
	159	case 4: __put_user_asm(x,ptr,retval,"l","k","ir",-EFAULT); break;\
5ad0d383	160	case 8: __put_user_asm(x,ptr,retval,"q","","Zr",-EFAULT); break;\
1da177e4 LT	161	default: __put_user_bad(); \
	162	} \
	163	} while (0)
	164
	165	/* FIXME: this hack is definitely wrong -AK */
	166	struct __large_struct { unsigned long buf[100]; };
	167	#define __m(x) ((struct __large_struct __user )(x))
	168
	169	/*
	170	* Tell gcc we read from memory instead of writing: this is because
	171	* we do not write to any memory gcc knows about, so there are no
	172	* aliasing issues.
	173	*/
	174	#define __put_user_asm(x, addr, err, itype, rtype, ltype, errno) \
383d079b	175	asm volatile( \
1da177e4 LT	176	"1: mov"itype" %"rtype"1,%2\n" \
	177	"2:\n" \
	178	".section .fixup,\"ax\"\n" \
	179	"3: mov %3,%0\n" \
	180	" jmp 2b\n" \
	181	".previous\n" \
	182	".section __ex_table,\"a\"\n" \
	183	" .align 8\n" \
	184	" .quad 1b,3b\n" \
	185	".previous" \
	186	: "=r"(err) \
	187	: ltype (x), "m"(__m(addr)), "i"(errno), "0"(err))
	188
	189
	190	#define __get_user_nocheck(x,ptr,size) \
	191	({ \
	192	int __gu_err; \
	193	unsigned long __gu_val; \
	194	__get_user_size(__gu_val,(ptr),(size),__gu_err); \
383d079b	195	(x) = (typeof(*(ptr)))__gu_val; \
1da177e4 LT	196	__gu_err; \
	197	})
	198
	199	extern int __get_user_1(void);
	200	extern int __get_user_2(void);
	201	extern int __get_user_4(void);
	202	extern int __get_user_8(void);
	203	extern int __get_user_bad(void);
	204
	205	#define __get_user_size(x,ptr,size,retval) \
	206	do { \
	207	retval = 0; \
	208	__chk_user_ptr(ptr); \
	209	switch (size) { \
	210	case 1: __get_user_asm(x,ptr,retval,"b","b","=q",-EFAULT); break;\
	211	case 2: __get_user_asm(x,ptr,retval,"w","w","=r",-EFAULT); break;\
	212	case 4: __get_user_asm(x,ptr,retval,"l","k","=r",-EFAULT); break;\
	213	case 8: __get_user_asm(x,ptr,retval,"q","","=r",-EFAULT); break;\
	214	default: (x) = __get_user_bad(); \
	215	} \
	216	} while (0)
	217
	218	#define __get_user_asm(x, addr, err, itype, rtype, ltype, errno) \
383d079b	219	asm volatile( \
1da177e4 LT	220	"1: mov"itype" %2,%"rtype"1\n" \
	221	"2:\n" \
	222	".section .fixup,\"ax\"\n" \
	223	"3: mov %3,%0\n" \
	224	" xor"itype" %"rtype"1,%"rtype"1\n" \
	225	" jmp 2b\n" \
	226	".previous\n" \
	227	".section __ex_table,\"a\"\n" \
	228	" .align 8\n" \
	229	" .quad 1b,3b\n" \
	230	".previous" \
	231	: "=r"(err), ltype (x) \
	232	: "m"(__m(addr)), "i"(errno), "0"(err))
	233
	234	/*
	235	* Copy To/From Userspace
	236	*/
	237
	238	/* Handles exceptions in both to and from, but doesn't do access_ok */
95912008 AK	239	__must_check unsigned long
	240	copy_user_generic(void to, const void from, unsigned len);
	241
	242	__must_check unsigned long
	243	copy_to_user(void __user to, const void from, unsigned len);
	244	__must_check unsigned long
	245	copy_from_user(void to, const void __user from, unsigned len);
	246	__must_check unsigned long
	247	copy_in_user(void __user to, const void __user from, unsigned len);
	248
	249	static __always_inline __must_check
	250	int __copy_from_user(void dst, const void __user src, unsigned size)
1da177e4	251	{
383d079b	252	int ret = 0;
1da177e4 LT	253	if (!__builtin_constant_p(size))
	254	return copy_user_generic(dst,(__force void *)src,size);
	255	switch (size) {
	256	case 1:__get_user_asm((u8)dst,(u8 __user *)src,ret,"b","b","=q",1);
	257	return ret;
	258	case 2:__get_user_asm((u16)dst,(u16 __user *)src,ret,"w","w","=r",2);
	259	return ret;
	260	case 4:__get_user_asm((u32)dst,(u32 __user *)src,ret,"l","k","=r",4);
	261	return ret;
	262	case 8:__get_user_asm((u64)dst,(u64 __user *)src,ret,"q","","=r",8);
	263	return ret;
	264	case 10:
	265	__get_user_asm((u64)dst,(u64 __user *)src,ret,"q","","=r",16);
	266	if (unlikely(ret)) return ret;
	267	__get_user_asm((u16)(8+(char)dst),(u16 __user )(8+(char __user *)src),ret,"w","w","=r",2);
	268	return ret;
	269	case 16:
	270	__get_user_asm((u64)dst,(u64 __user *)src,ret,"q","","=r",16);
	271	if (unlikely(ret)) return ret;
	272	__get_user_asm((u64)(8+(char)dst),(u64 __user )(8+(char __user *)src),ret,"q","","=r",8);
	273	return ret;
	274	default:
	275	return copy_user_generic(dst,(__force void *)src,size);
	276	}
	277	}
	278
95912008 AK	279	static __always_inline __must_check
95912008 AK	280	int __copy_to_user(void __user dst, const void src, unsigned size)
1da177e4	281	{
383d079b	282	int ret = 0;
1da177e4 LT	283	if (!__builtin_constant_p(size))
	284	return copy_user_generic((__force void *)dst,src,size);
	285	switch (size) {
	286	case 1:__put_user_asm((u8)src,(u8 __user *)dst,ret,"b","b","iq",1);
	287	return ret;
	288	case 2:__put_user_asm((u16)src,(u16 __user *)dst,ret,"w","w","ir",2);
	289	return ret;
	290	case 4:__put_user_asm((u32)src,(u32 __user *)dst,ret,"l","k","ir",4);
	291	return ret;
	292	case 8:__put_user_asm((u64)src,(u64 __user *)dst,ret,"q","","ir",8);
	293	return ret;
	294	case 10:
	295	__put_user_asm((u64)src,(u64 __user *)dst,ret,"q","","ir",10);
	296	if (unlikely(ret)) return ret;
	297	asm("":::"memory");
	298	__put_user_asm(4[(u16)src],4+(u16 __user )dst,ret,"w","w","ir",2);
	299	return ret;
	300	case 16:
	301	__put_user_asm((u64)src,(u64 __user *)dst,ret,"q","","ir",16);
	302	if (unlikely(ret)) return ret;
	303	asm("":::"memory");
	304	__put_user_asm(1[(u64)src],1+(u64 __user )dst,ret,"q","","ir",8);
	305	return ret;
	306	default:
	307	return copy_user_generic((__force void *)dst,src,size);
	308	}
	309	}
	310
95912008 AK	311	static __always_inline __must_check
95912008 AK	312	int __copy_in_user(void __user dst, const void __user src, unsigned size)
1da177e4	313	{
383d079b	314	int ret = 0;
1da177e4 LT	315	if (!__builtin_constant_p(size))
	316	return copy_user_generic((__force void )dst,(__force void )src,size);
	317	switch (size) {
	318	case 1: {
	319	u8 tmp;
	320	__get_user_asm(tmp,(u8 __user *)src,ret,"b","b","=q",1);
	321	if (likely(!ret))
	322	__put_user_asm(tmp,(u8 __user *)dst,ret,"b","b","iq",1);
	323	return ret;
	324	}
	325	case 2: {
	326	u16 tmp;
	327	__get_user_asm(tmp,(u16 __user *)src,ret,"w","w","=r",2);
	328	if (likely(!ret))
	329	__put_user_asm(tmp,(u16 __user *)dst,ret,"w","w","ir",2);
	330	return ret;
	331	}
	332
	333	case 4: {
	334	u32 tmp;
	335	__get_user_asm(tmp,(u32 __user *)src,ret,"l","k","=r",4);
	336	if (likely(!ret))
	337	__put_user_asm(tmp,(u32 __user *)dst,ret,"l","k","ir",4);
	338	return ret;
	339	}
	340	case 8: {
	341	u64 tmp;
	342	__get_user_asm(tmp,(u64 __user *)src,ret,"q","","=r",8);
	343	if (likely(!ret))
	344	__put_user_asm(tmp,(u64 __user *)dst,ret,"q","","ir",8);
	345	return ret;
	346	}
	347	default:
	348	return copy_user_generic((__force void )dst,(__force void )src,size);
	349	}
	350	}
	351
95912008 AK	352	__must_check long
	353	strncpy_from_user(char dst, const char __user src, long count);
	354	__must_check long
	355	__strncpy_from_user(char dst, const char __user src, long count);
	356	__must_check long strnlen_user(const char __user *str, long n);
	357	__must_check long __strnlen_user(const char __user *str, long n);
	358	__must_check long strlen_user(const char __user *str);
	359	__must_check unsigned long clear_user(void __user *mem, unsigned long len);
	360	__must_check unsigned long __clear_user(void __user *mem, unsigned long len);
	361
	362	__must_check long __copy_from_user_inatomic(void dst, const void __user src, unsigned size);
b885808e AK	363
	364	static __must_check __always_inline int
	365	__copy_to_user_inatomic(void __user dst, const void src, unsigned size)
	366	{
	367	return copy_user_generic((__force void *)dst, src, size);
	368	}
1da177e4	369
0812a579 AK	370	#define ARCH_HAS_NOCACHE_UACCESS 1
	371	extern long __copy_user_nocache(void dst, const void __user src, unsigned size, int zerorest);
	372
	373	static inline int __copy_from_user_nocache(void dst, const void __user src, unsigned size)
	374	{
	375	might_sleep();
ecb7524c	376	return __copy_user_nocache(dst, src, size, 1);
0812a579 AK	377	}
	378
	379	static inline int __copy_from_user_inatomic_nocache(void dst, const void __user src, unsigned size)
	380	{
ecb7524c	381	return __copy_user_nocache(dst, src, size, 0);
0812a579 AK	382	}
0812a579 AK	383
1da177e4	384	#endif /* __X86_64_UACCESS_H */