[deliverable/linux.git] / arch / x86 / include / asm / uaccess_64.h

#ifndef _ASM_X86_UACCESS_64_H
#define _ASM_X86_UACCESS_64_H

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

/*
 * Copy To/From Userspace
 */

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

static __always_inline __must_check unsigned long
copy_user_generic(void *to, const void *from, unsigned len)
{
	unsigned ret;

	/*
	 * If CPU has ERMS feature, use copy_user_enhanced_fast_string.
	 * Otherwise, if CPU has rep_good feature, use copy_user_generic_string.
	 * Otherwise, use copy_user_generic_unrolled.
	 */
	alternative_call_2(copy_user_generic_unrolled,
			 copy_user_generic_string,
			 X86_FEATURE_REP_GOOD,
			 copy_user_enhanced_fast_string,
			 X86_FEATURE_ERMS,
			 ASM_OUTPUT2("=a" (ret), "=D" (to), "=S" (from),
				     "=d" (len)),
			 "1" (to), "2" (from), "3" (len)
			 : "memory", "rcx", "r8", "r9", "r10", "r11");
	return ret;
}

__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_nocheck(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:
		__uaccess_begin();
		__get_user_asm(*(u8 *)dst, (u8 __user *)src,
			      ret, "b", "b", "=q", 1);
		__uaccess_end();
		return ret;
	case 2:
		__uaccess_begin();
		__get_user_asm(*(u16 *)dst, (u16 __user *)src,
			      ret, "w", "w", "=r", 2);
		__uaccess_end();
		return ret;
	case 4:
		__uaccess_begin();
		__get_user_asm(*(u32 *)dst, (u32 __user *)src,
			      ret, "l", "k", "=r", 4);
		__uaccess_end();
		return ret;
	case 8:
		__uaccess_begin();
		__get_user_asm(*(u64 *)dst, (u64 __user *)src,
			      ret, "q", "", "=r", 8);
		__uaccess_end();
		return ret;
	case 10:
		__uaccess_begin();
		__get_user_asm(*(u64 *)dst, (u64 __user *)src,
			       ret, "q", "", "=r", 10);
		if (likely(!ret))
			__get_user_asm(*(u16 *)(8 + (char *)dst),
				       (u16 __user *)(8 + (char __user *)src),
				       ret, "w", "w", "=r", 2);
		__uaccess_end();
		return ret;
	case 16:
		__uaccess_begin();
		__get_user_asm(*(u64 *)dst, (u64 __user *)src,
			       ret, "q", "", "=r", 16);
		if (likely(!ret))
			__get_user_asm(*(u64 *)(8 + (char *)dst),
				       (u64 __user *)(8 + (char __user *)src),
				       ret, "q", "", "=r", 8);
		__uaccess_end();
		return ret;
	default:
		return copy_user_generic(dst, (__force void *)src, size);
	}
}

static __always_inline __must_check
int __copy_from_user(void *dst, const void __user *src, unsigned size)
{
	might_fault();
	return __copy_from_user_nocheck(dst, src, size);
}

static __always_inline __must_check
int __copy_to_user_nocheck(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:
		__uaccess_begin();
		__put_user_asm(*(u8 *)src, (u8 __user *)dst,
			      ret, "b", "b", "iq", 1);
		__uaccess_end();
		return ret;
	case 2:
		__uaccess_begin();
		__put_user_asm(*(u16 *)src, (u16 __user *)dst,
			      ret, "w", "w", "ir", 2);
		__uaccess_end();
		return ret;
	case 4:
		__uaccess_begin();
		__put_user_asm(*(u32 *)src, (u32 __user *)dst,
			      ret, "l", "k", "ir", 4);
		__uaccess_end();
		return ret;
	case 8:
		__uaccess_begin();
		__put_user_asm(*(u64 *)src, (u64 __user *)dst,
			      ret, "q", "", "er", 8);
		__uaccess_end();
		return ret;
	case 10:
		__uaccess_begin();
		__put_user_asm(*(u64 *)src, (u64 __user *)dst,
			       ret, "q", "", "er", 10);
		if (likely(!ret)) {
			asm("":::"memory");
			__put_user_asm(4[(u16 *)src], 4 + (u16 __user *)dst,
				       ret, "w", "w", "ir", 2);
		}
		__uaccess_end();
		return ret;
	case 16:
		__uaccess_begin();
		__put_user_asm(*(u64 *)src, (u64 __user *)dst,
			       ret, "q", "", "er", 16);
		if (likely(!ret)) {
			asm("":::"memory");
			__put_user_asm(1[(u64 *)src], 1 + (u64 __user *)dst,
				       ret, "q", "", "er", 8);
		}
		__uaccess_end();
		return ret;
	default:
		return copy_user_generic((__force void *)dst, src, size);
	}
}

static __always_inline __must_check
int __copy_to_user(void __user *dst, const void *src, unsigned size)
{
	might_fault();
	return __copy_to_user_nocheck(dst, src, size);
}

static __always_inline __must_check
int __copy_in_user(void __user *dst, const void __user *src, unsigned size)
{
	int ret = 0;

	might_fault();
	if (!__builtin_constant_p(size))
		return copy_user_generic((__force void *)dst,
					 (__force void *)src, size);
	switch (size) {
	case 1: {
		u8 tmp;
		__uaccess_begin();
		__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);
		__uaccess_end();
		return ret;
	}
	case 2: {
		u16 tmp;
		__uaccess_begin();
		__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);
		__uaccess_end();
		return ret;
	}

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

static __must_check __always_inline int
__copy_from_user_inatomic(void *dst, const void __user *src, unsigned size)
{
	return __copy_from_user_nocheck(dst, src, size);
}

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

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_fault();
	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);
}

unsigned long
copy_user_handle_tail(char *to, char *from, unsigned len);

#endif /* _ASM_X86_UACCESS_64_H */
Commit	Line	Data
1965aae3 PA	1	#ifndef _ASM_X86_UACCESS_64_H
1965aae3 PA	2	#define _ASM_X86_UACCESS_64_H
1da177e4 LT	3
	4	/*
	5	* User space memory access functions
	6	*/
1da177e4 LT	7	#include <linux/compiler.h>
1da177e4 LT	8	#include <linux/errno.h>
16dbc6c9	9	#include <linux/lockdep.h>
1b1d9258	10	#include <asm/alternative.h>
cd4d09ec	11	#include <asm/cpufeatures.h>
1da177e4 LT	12	#include <asm/page.h>
1da177e4 LT	13
1da177e4 LT	14	/*
	15	* Copy To/From Userspace
	16	*/
	17
	18	/* Handles exceptions in both to and from, but doesn't do access_ok */
95912008	19	__must_check unsigned long
954e482b FY	20	copy_user_enhanced_fast_string(void to, const void from, unsigned len);
954e482b FY	21	__must_check unsigned long
1b1d9258 JB	22	copy_user_generic_string(void to, const void from, unsigned len);
	23	__must_check unsigned long
	24	copy_user_generic_unrolled(void to, const void from, unsigned len);
	25
	26	static __always_inline __must_check unsigned long
	27	copy_user_generic(void to, const void from, unsigned len)
	28	{
	29	unsigned ret;
	30
954e482b FY	31	/*
	32	* If CPU has ERMS feature, use copy_user_enhanced_fast_string.
	33	* Otherwise, if CPU has rep_good feature, use copy_user_generic_string.
	34	* Otherwise, use copy_user_generic_unrolled.
	35	*/
	36	alternative_call_2(copy_user_generic_unrolled,
1b1d9258 JB	37	copy_user_generic_string,
1b1d9258 JB	38	X86_FEATURE_REP_GOOD,
954e482b FY	39	copy_user_enhanced_fast_string,
954e482b FY	40	X86_FEATURE_ERMS,
1b1d9258 JB	41	ASM_OUTPUT2("=a" (ret), "=D" (to), "=S" (from),
	42	"=d" (len)),
	43	"1" (to), "2" (from), "3" (len)
	44	: "memory", "rcx", "r8", "r9", "r10", "r11");
	45	return ret;
	46	}
95912008	47
95912008	48	__must_check unsigned long
95912008 AK	49	copy_in_user(void __user to, const void __user from, unsigned len);
	50
	51	static __always_inline __must_check
ff47ab4f	52	int __copy_from_user_nocheck(void dst, const void __user src, unsigned size)
b896313e	53	{
383d079b	54	int ret = 0;
c10d38dd	55
1da177e4	56	if (!__builtin_constant_p(size))
b896313e JP	57	return copy_user_generic(dst, (__force void *)src, size);
b896313e JP	58	switch (size) {
11f1a4b9 LT	59	case 1:
	60	__uaccess_begin();
	61	__get_user_asm((u8 )dst, (u8 __user *)src,
b896313e	62	ret, "b", "b", "=q", 1);
11f1a4b9	63	__uaccess_end();
1da177e4	64	return ret;
11f1a4b9 LT	65	case 2:
	66	__uaccess_begin();
	67	__get_user_asm((u16 )dst, (u16 __user *)src,
b896313e	68	ret, "w", "w", "=r", 2);
11f1a4b9	69	__uaccess_end();
1da177e4	70	return ret;
11f1a4b9 LT	71	case 4:
	72	__uaccess_begin();
	73	__get_user_asm((u32 )dst, (u32 __user *)src,
b896313e	74	ret, "l", "k", "=r", 4);
11f1a4b9	75	__uaccess_end();
b896313e	76	return ret;
11f1a4b9 LT	77	case 8:
	78	__uaccess_begin();
	79	__get_user_asm((u64 )dst, (u64 __user *)src,
b896313e	80	ret, "q", "", "=r", 8);
11f1a4b9	81	__uaccess_end();
1da177e4	82	return ret;
1da177e4	83	case 10:
11f1a4b9	84	__uaccess_begin();
b896313e	85	__get_user_asm((u64 )dst, (u64 __user *)src,
20a4a236	86	ret, "q", "", "=r", 10);
11f1a4b9 LT	87	if (likely(!ret))
	88	__get_user_asm((u16 )(8 + (char *)dst),
	89	(u16 __user )(8 + (char __user )src),
	90	ret, "w", "w", "=r", 2);
	91	__uaccess_end();
b896313e	92	return ret;
1da177e4	93	case 16:
11f1a4b9	94	__uaccess_begin();
b896313e JP	95	__get_user_asm((u64 )dst, (u64 __user *)src,
b896313e JP	96	ret, "q", "", "=r", 16);
11f1a4b9 LT	97	if (likely(!ret))
	98	__get_user_asm((u64 )(8 + (char *)dst),
	99	(u64 __user )(8 + (char __user )src),
	100	ret, "q", "", "=r", 8);
	101	__uaccess_end();
b896313e	102	return ret;
1da177e4	103	default:
b896313e	104	return copy_user_generic(dst, (__force void *)src, size);
1da177e4	105	}
b896313e	106	}
1da177e4	107
95912008	108	static __always_inline __must_check
ff47ab4f AK	109	int __copy_from_user(void dst, const void __user src, unsigned size)
	110	{
	111	might_fault();
	112	return __copy_from_user_nocheck(dst, src, size);
	113	}
	114
	115	static __always_inline __must_check
	116	int __copy_to_user_nocheck(void __user dst, const void src, unsigned size)
b896313e	117	{
383d079b	118	int ret = 0;
c10d38dd	119
1da177e4	120	if (!__builtin_constant_p(size))
b896313e JP	121	return copy_user_generic((__force void *)dst, src, size);
b896313e JP	122	switch (size) {
11f1a4b9 LT	123	case 1:
	124	__uaccess_begin();
	125	__put_user_asm((u8 )src, (u8 __user *)dst,
b896313e	126	ret, "b", "b", "iq", 1);
11f1a4b9	127	__uaccess_end();
1da177e4	128	return ret;
11f1a4b9 LT	129	case 2:
	130	__uaccess_begin();
	131	__put_user_asm((u16 )src, (u16 __user *)dst,
b896313e	132	ret, "w", "w", "ir", 2);
11f1a4b9	133	__uaccess_end();
1da177e4	134	return ret;
11f1a4b9 LT	135	case 4:
	136	__uaccess_begin();
	137	__put_user_asm((u32 )src, (u32 __user *)dst,
b896313e	138	ret, "l", "k", "ir", 4);
11f1a4b9	139	__uaccess_end();
b896313e	140	return ret;
11f1a4b9 LT	141	case 8:
	142	__uaccess_begin();
	143	__put_user_asm((u64 )src, (u64 __user *)dst,
155b7352	144	ret, "q", "", "er", 8);
11f1a4b9	145	__uaccess_end();
1da177e4	146	return ret;
1da177e4	147	case 10:
11f1a4b9	148	__uaccess_begin();
b896313e	149	__put_user_asm((u64 )src, (u64 __user *)dst,
155b7352	150	ret, "q", "", "er", 10);
11f1a4b9 LT	151	if (likely(!ret)) {
	152	asm("":::"memory");
	153	__put_user_asm(4[(u16 )src], 4 + (u16 __user )dst,
	154	ret, "w", "w", "ir", 2);
	155	}
	156	__uaccess_end();
b896313e	157	return ret;
1da177e4	158	case 16:
11f1a4b9	159	__uaccess_begin();
b896313e	160	__put_user_asm((u64 )src, (u64 __user *)dst,
155b7352	161	ret, "q", "", "er", 16);
11f1a4b9 LT	162	if (likely(!ret)) {
	163	asm("":::"memory");
	164	__put_user_asm(1[(u64 )src], 1 + (u64 __user )dst,
	165	ret, "q", "", "er", 8);
	166	}
	167	__uaccess_end();
b896313e	168	return ret;
1da177e4	169	default:
b896313e	170	return copy_user_generic((__force void *)dst, src, size);
1da177e4	171	}
b896313e	172	}
1da177e4	173
ff47ab4f AK	174	static __always_inline __must_check
	175	int __copy_to_user(void __user dst, const void src, unsigned size)
	176	{
	177	might_fault();
	178	return __copy_to_user_nocheck(dst, src, size);
	179	}
	180
95912008 AK	181	static __always_inline __must_check
95912008 AK	182	int __copy_in_user(void __user dst, const void __user src, unsigned size)
b896313e	183	{
383d079b	184	int ret = 0;
c10d38dd	185
3ee1afa3	186	might_fault();
1da177e4	187	if (!__builtin_constant_p(size))
b896313e JP	188	return copy_user_generic((__force void *)dst,
	189	(__force void *)src, size);
	190	switch (size) {
	191	case 1: {
1da177e4	192	u8 tmp;
11f1a4b9	193	__uaccess_begin();
b896313e JP	194	__get_user_asm(tmp, (u8 __user *)src,
b896313e JP	195	ret, "b", "b", "=q", 1);
1da177e4	196	if (likely(!ret))
b896313e JP	197	__put_user_asm(tmp, (u8 __user *)dst,
b896313e JP	198	ret, "b", "b", "iq", 1);
11f1a4b9	199	__uaccess_end();
1da177e4 LT	200	return ret;
1da177e4 LT	201	}
b896313e	202	case 2: {
1da177e4	203	u16 tmp;
11f1a4b9	204	__uaccess_begin();
b896313e JP	205	__get_user_asm(tmp, (u16 __user *)src,
b896313e JP	206	ret, "w", "w", "=r", 2);
1da177e4	207	if (likely(!ret))
b896313e JP	208	__put_user_asm(tmp, (u16 __user *)dst,
b896313e JP	209	ret, "w", "w", "ir", 2);
11f1a4b9	210	__uaccess_end();
1da177e4 LT	211	return ret;
	212	}
	213
b896313e	214	case 4: {
1da177e4	215	u32 tmp;
11f1a4b9	216	__uaccess_begin();
b896313e JP	217	__get_user_asm(tmp, (u32 __user *)src,
b896313e JP	218	ret, "l", "k", "=r", 4);
1da177e4	219	if (likely(!ret))
b896313e JP	220	__put_user_asm(tmp, (u32 __user *)dst,
b896313e JP	221	ret, "l", "k", "ir", 4);
11f1a4b9	222	__uaccess_end();
1da177e4 LT	223	return ret;
1da177e4 LT	224	}
b896313e	225	case 8: {
1da177e4	226	u64 tmp;
11f1a4b9	227	__uaccess_begin();
b896313e JP	228	__get_user_asm(tmp, (u64 __user *)src,
b896313e JP	229	ret, "q", "", "=r", 8);
1da177e4	230	if (likely(!ret))
b896313e	231	__put_user_asm(tmp, (u64 __user *)dst,
155b7352	232	ret, "q", "", "er", 8);
11f1a4b9	233	__uaccess_end();
1da177e4 LT	234	return ret;
	235	}
	236	default:
b896313e JP	237	return copy_user_generic((__force void *)dst,
b896313e JP	238	(__force void *)src, size);
1da177e4	239	}
b896313e	240	}
1da177e4	241
14722485 JB	242	static __must_check __always_inline int
	243	__copy_from_user_inatomic(void dst, const void __user src, unsigned size)
	244	{
df90ca96	245	return __copy_from_user_nocheck(dst, src, size);
14722485	246	}
b885808e AK	247
	248	static __must_check __always_inline int
	249	__copy_to_user_inatomic(void __user dst, const void src, unsigned size)
	250	{
df90ca96	251	return __copy_to_user_nocheck(dst, src, size);
b885808e	252	}
1da177e4	253
b896313e JP	254	extern long __copy_user_nocache(void dst, const void __user src,
b896313e JP	255	unsigned size, int zerorest);
0812a579	256
f1800536 IM	257	static inline int
f1800536 IM	258	__copy_from_user_nocache(void dst, const void __user src, unsigned size)
0812a579	259	{
016be2e5	260	might_fault();
f1800536	261	return __copy_user_nocache(dst, src, size, 1);
0812a579 AK	262	}
0812a579 AK	263
f1800536 IM	264	static inline int
	265	__copy_from_user_inatomic_nocache(void dst, const void __user src,
	266	unsigned size)
0812a579	267	{
f1800536	268	return __copy_user_nocache(dst, src, size, 0);
0812a579 AK	269	}
0812a579 AK	270
1129585a	271	unsigned long
cae2a173	272	copy_user_handle_tail(char to, char from, unsigned len);
1129585a	273
1965aae3	274	#endif /* _ASM_X86_UACCESS_64_H */