[GitHub/mt8127/android_kernel_alcatel_ttab.git] / arch / score / include / asm / uaccess.h

#ifndef __SCORE_UACCESS_H
#define __SCORE_UACCESS_H

#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/thread_info.h>

#define VERIFY_READ		0
#define VERIFY_WRITE		1

#define get_ds()		(KERNEL_DS)
#define get_fs()		(current_thread_info()->addr_limit)
#define segment_eq(a, b)	((a).seg == (b).seg)

/*
 * Is a address valid? This does a straighforward calculation rather
 * than tests.
 *
 * Address valid if:
 *  - "addr" doesn't have any high-bits set
 *  - AND "size" doesn't have any high-bits set
 *  - AND "addr+size" doesn't have any high-bits set
 *  - OR we are in kernel mode.
 *
 * __ua_size() is a trick to avoid runtime checking of positive constant
 * sizes; for those we already know at compile time that the size is ok.
 */
#define __ua_size(size)							\
	((__builtin_constant_p(size) && (signed long) (size) > 0) ? 0 : (size))

/*
 * access_ok: - Checks if a user space pointer is valid
 * @type: Type of access: %VERIFY_READ or %VERIFY_WRITE.  Note that
 *        %VERIFY_WRITE is a superset of %VERIFY_READ - if it is safe
 *        to write to a block, it is always safe to read from it.
 * @addr: User space pointer to start of block to check
 * @size: Size of block to check
 *
 * Context: User context only.  This function may sleep.
 *
 * Checks if a pointer to a block of memory in user space is valid.
 *
 * Returns true (nonzero) if the memory block may be valid, false (zero)
 * if it is definitely invalid.
 *
 * Note that, depending on architecture, this function probably just
 * checks that the pointer is in the user space range - after calling
 * this function, memory access functions may still return -EFAULT.
 */

#define __access_ok(addr, size)					\
	(((long)((get_fs().seg) &				\
		 ((addr) | ((addr) + (size)) |			\
		  __ua_size(size)))) == 0)

#define access_ok(type, addr, size)				\
	likely(__access_ok((unsigned long)(addr), (size)))

/*
 * 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)))

/*
 * 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)))

/*
 * __put_user: - Write a simple value into user space, with less checking.
 * @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.
 *
 * Caller must check the pointer with access_ok() before calling this
 * function.
 *
 * Returns zero on success, or -EFAULT on error.
 */
#define __put_user(x, ptr) __put_user_nocheck((x), (ptr), sizeof(*(ptr)))

/*
 * __get_user: - Get a simple variable from user space, with less checking.
 * @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.
 *
 * Caller must check the pointer with access_ok() before calling this
 * function.
 *
 * Returns zero on success, or -EFAULT on error.
 * On error, the variable @x is set to zero.
 */
#define __get_user(x, ptr) __get_user_nocheck((x), (ptr), sizeof(*(ptr)))

struct __large_struct { unsigned long buf[100]; };
#define __m(x) (*(struct __large_struct __user *)(x))

/*
 * Yuck.  We need two variants, one for 64bit operation and one
 * for 32 bit mode and old iron.
 */
extern void __get_user_unknown(void);

#define __get_user_common(val, size, ptr)				\
do {									\
	switch (size) {							\
	case 1:								\
		__get_user_asm(val, "lb", ptr);				\
		break;							\
	case 2:								\
		__get_user_asm(val, "lh", ptr);				\
		 break;							\
	case 4:								\
		__get_user_asm(val, "lw", ptr);				\
		 break;							\
	case 8: 							\
		if (__copy_from_user((void *)&val, ptr, 8) == 0)	\
			__gu_err = 0;					\
		else							\
			__gu_err = -EFAULT;				\
		break;							\
	default:							\
		__get_user_unknown();					\
		break;							\
	}								\
} while (0)

#define __get_user_nocheck(x, ptr, size)				\
({									\
	long __gu_err = 0;						\
	__get_user_common((x), size, ptr);				\
	__gu_err;							\
})

#define __get_user_check(x, ptr, size)					\
({									\
	long __gu_err = -EFAULT;					\
	const __typeof__(*(ptr)) __user *__gu_ptr = (ptr);		\
									\
	if (likely(access_ok(VERIFY_READ, __gu_ptr, size)))		\
		__get_user_common((x), size, __gu_ptr);			\
	else								\
		(x) = 0;						\
									\
	__gu_err;							\
})

#define __get_user_asm(val, insn, addr)					\
{									\
	long __gu_tmp;							\
									\
	__asm__ __volatile__(						\
		"1:" insn " %1, %3\n"					\
		"2:\n"							\
		".section .fixup,\"ax\"\n"				\
		"3:li	%0, %4\n"					\
		"li	%1, 0\n"					\
		"j	2b\n"						\
		".previous\n"						\
		".section __ex_table,\"a\"\n"				\
		".word	1b, 3b\n"					\
		".previous\n"						\
		: "=r" (__gu_err), "=r" (__gu_tmp)			\
		: "0" (0), "o" (__m(addr)), "i" (-EFAULT));		\
									\
		(val) = (__typeof__(*(addr))) __gu_tmp;			\
}

/*
 * Yuck.  We need two variants, one for 64bit operation and one
 * for 32 bit mode and old iron.
 */
#define __put_user_nocheck(val, ptr, size)				\
({									\
	__typeof__(*(ptr)) __pu_val;					\
	long __pu_err = 0;						\
									\
	__pu_val = (val);						\
	switch (size) {							\
	case 1:								\
		__put_user_asm("sb", ptr);				\
		break;							\
	case 2:								\
		__put_user_asm("sh", ptr);				\
		break;							\
	case 4:								\
		__put_user_asm("sw", ptr);				\
		break;							\
	case 8: 							\
		if ((__copy_to_user((void *)ptr, &__pu_val, 8)) == 0)	\
			__pu_err = 0;					\
		else							\
			__pu_err = -EFAULT;				\
		break;							\
	default:							\
		 __put_user_unknown();					\
		 break;							\
	}								\
	__pu_err;							\
})


#define __put_user_check(val, ptr, size)				\
({									\
	__typeof__(*(ptr)) __user *__pu_addr = (ptr);			\
	__typeof__(*(ptr)) __pu_val = (val);				\
	long __pu_err = -EFAULT;					\
									\
	if (likely(access_ok(VERIFY_WRITE, __pu_addr, size))) {		\
		switch (size) {						\
		case 1:							\
			__put_user_asm("sb", __pu_addr);		\
			break;						\
		case 2:							\
			__put_user_asm("sh", __pu_addr);		\
			break;						\
		case 4:							\
			__put_user_asm("sw", __pu_addr);		\
			break;						\
		case 8: 						\
			if ((__copy_to_user((void *)__pu_addr, &__pu_val, 8)) == 0)\
				__pu_err = 0;				\
			else						\
				__pu_err = -EFAULT;			\
			break;						\
		default:						\
			__put_user_unknown();				\
			break;						\
		}							\
	}								\
	__pu_err;							\
})

#define __put_user_asm(insn, ptr)					\
	__asm__ __volatile__(						\
		"1:" insn " %2, %3\n"					\
		"2:\n"							\
		".section .fixup,\"ax\"\n"				\
		"3:li %0, %4\n"						\
		"j 2b\n"						\
		".previous\n"						\
		".section __ex_table,\"a\"\n"				\
		".word 1b, 3b\n"					\
		".previous\n"						\
		: "=r" (__pu_err)					\
		: "0" (0), "r" (__pu_val), "o" (__m(ptr)),		\
		  "i" (-EFAULT));

extern void __put_user_unknown(void);
extern int __copy_tofrom_user(void *to, const void *from, unsigned long len);

static inline unsigned long
copy_from_user(void *to, const void *from, unsigned long len)
{
	unsigned long res = len;

	if (likely(access_ok(VERIFY_READ, from, len)))
		res = __copy_tofrom_user(to, from, len);

	if (unlikely(res))
		memset(to + (len - res), 0, res);

	return res;
}

static inline unsigned long
copy_to_user(void *to, const void *from, unsigned long len)
{
	if (likely(access_ok(VERIFY_WRITE, to, len)))
		len = __copy_tofrom_user(to, from, len);

	return len;
}

static inline unsigned long
__copy_from_user(void *to, const void *from, unsigned long len)
{
	unsigned long left = __copy_tofrom_user(to, from, len);
	if (unlikely(left))
		memset(to + (len - left), 0, left);
	return left;
}

#define __copy_to_user(to, from, len)		\
		__copy_tofrom_user((to), (from), (len))

static inline unsigned long
__copy_to_user_inatomic(void *to, const void *from, unsigned long len)
{
	return __copy_to_user(to, from, len);
}

static inline unsigned long
__copy_from_user_inatomic(void *to, const void *from, unsigned long len)
{
	return __copy_tofrom_user(to, from, len);
}

#define __copy_in_user(to, from, len)	__copy_tofrom_user(to, from, len)

static inline unsigned long
copy_in_user(void *to, const void *from, unsigned long len)
{
	if (access_ok(VERIFY_READ, from, len) &&
		      access_ok(VERFITY_WRITE, to, len))
		return __copy_tofrom_user(to, from, len);
}

/*
 * __clear_user: - Zero a block of memory in user space, with less checking.
 * @to:   Destination address, in user space.
 * @n:    Number of bytes to zero.
 *
 * Zero a block of memory in user space.  Caller must check
 * the specified block with access_ok() before calling this function.
 *
 * Returns number of bytes that could not be cleared.
 * On success, this will be zero.
 */
extern unsigned long __clear_user(void __user *src, unsigned long size);

static inline unsigned long clear_user(char *src, unsigned long size)
{
	if (access_ok(VERIFY_WRITE, src, size))
		return __clear_user(src, size);

	return -EFAULT;
}
/*
 * __strncpy_from_user: - Copy a NUL terminated string from userspace, with less checking.
 * @dst:   Destination address, in kernel space.  This buffer must be at
 *         least @count bytes long.
 * @src:   Source address, in user space.
 * @count: Maximum number of bytes to copy, including the trailing NUL.
 *
 * Copies a NUL-terminated string from userspace to kernel space.
 * Caller must check the specified block with access_ok() before calling
 * this function.
 *
 * On success, returns the length of the string (not including the trailing
 * NUL).
 *
 * If access to userspace fails, returns -EFAULT (some data may have been
 * copied).
 *
 * If @count is smaller than the length of the string, copies @count bytes
 * and returns @count.
 */
extern int __strncpy_from_user(char *dst, const char *src, long len);

static inline int strncpy_from_user(char *dst, const char *src, long len)
{
	if (access_ok(VERIFY_READ, src, 1))
		return __strncpy_from_user(dst, src, len);

	return -EFAULT;
}

extern int __strlen_user(const char *src);
static inline long strlen_user(const char __user *src)
{
	return __strlen_user(src);
}

extern int __strnlen_user(const char *str, long len);
static inline long strnlen_user(const char __user *str, long len)
{
	if (!access_ok(VERIFY_READ, str, 0))
		return 0;
	else		
		return __strnlen_user(str, len);
}

struct exception_table_entry {
	unsigned long insn;
	unsigned long fixup;
};

extern int fixup_exception(struct pt_regs *regs);

#endif /* __SCORE_UACCESS_H */
Commit	Line	Data
ffa818b4 CL	1	#ifndef __SCORE_UACCESS_H
	2	#define __SCORE_UACCESS_H
	3
	4	#include <linux/kernel.h>
	5	#include <linux/errno.h>
	6	#include <linux/thread_info.h>
	7
	8	#define VERIFY_READ 0
	9	#define VERIFY_WRITE 1
	10
	11	#define get_ds() (KERNEL_DS)
	12	#define get_fs() (current_thread_info()->addr_limit)
	13	#define segment_eq(a, b) ((a).seg == (b).seg)
	14
6bc9a396	15	/*
ffa818b4 CL	16	* Is a address valid? This does a straighforward calculation rather
	17	* than tests.
	18	*
	19	* Address valid if:
	20	* - "addr" doesn't have any high-bits set
	21	* - AND "size" doesn't have any high-bits set
	22	* - AND "addr+size" doesn't have any high-bits set
	23	* - OR we are in kernel mode.
6bc9a396	24	*
ffa818b4 CL	25	* __ua_size() is a trick to avoid runtime checking of positive constant
ffa818b4 CL	26	* sizes; for those we already know at compile time that the size is ok.
6bc9a396	27	*/
ffa818b4 CL	28	#define __ua_size(size) \
	29	((__builtin_constant_p(size) && (signed long) (size) > 0) ? 0 : (size))
	30
	31	/*
	32	* access_ok: - Checks if a user space pointer is valid
	33	* @type: Type of access: %VERIFY_READ or %VERIFY_WRITE. Note that
	34	* %VERIFY_WRITE is a superset of %VERIFY_READ - if it is safe
	35	* to write to a block, it is always safe to read from it.
	36	* @addr: User space pointer to start of block to check
	37	* @size: Size of block to check
	38	*
	39	* Context: User context only. This function may sleep.
	40	*
	41	* Checks if a pointer to a block of memory in user space is valid.
	42	*
	43	* Returns true (nonzero) if the memory block may be valid, false (zero)
	44	* if it is definitely invalid.
	45	*
	46	* Note that, depending on architecture, this function probably just
	47	* checks that the pointer is in the user space range - after calling
	48	* this function, memory access functions may still return -EFAULT.
	49	*/
	50
	51	#define __access_ok(addr, size) \
	52	(((long)((get_fs().seg) & \
	53	((addr) \| ((addr) + (size)) \| \
	54	__ua_size(size)))) == 0)
	55
	56	#define access_ok(type, addr, size) \
	57	likely(__access_ok((unsigned long)(addr), (size)))
	58
	59	/*
	60	* put_user: - Write a simple value into user space.
	61	* @x: Value to copy to user space.
	62	* @ptr: Destination address, in user space.
	63	*
	64	* Context: User context only. This function may sleep.
	65	*
	66	* This macro copies a single simple value from kernel space to user
	67	* space. It supports simple types like char and int, but not larger
	68	* data types like structures or arrays.
	69	*
	70	* @ptr must have pointer-to-simple-variable type, and @x must be assignable
	71	* to the result of dereferencing @ptr.
	72	*
	73	* Returns zero on success, or -EFAULT on error.
	74	*/
	75	#define put_user(x, ptr) __put_user_check((x), (ptr), sizeof(*(ptr)))
	76
	77	/*
	78	* get_user: - Get a simple variable from user space.
	79	* @x: Variable to store result.
	80	* @ptr: Source address, in user space.
	81	*
	82	* Context: User context only. This function may sleep.
	83	*
	84	* This macro copies a single simple variable from user space to kernel
	85	* space. It supports simple types like char and int, but not larger
	86	* data types like structures or arrays.
	87	*
	88	* @ptr must have pointer-to-simple-variable type, and the result of
	89	* dereferencing @ptr must be assignable to @x without a cast.
	90	*
	91	* Returns zero on success, or -EFAULT on error.
92	* On error, the variable @x is set to zero.
93	*/
94	#define get_user(x, ptr) __get_user_check((x), (ptr), sizeof(*(ptr)))
95
96	/*
97	* __put_user: - Write a simple value into user space, with less checking.
98	* @x: Value to copy to user space.
99	* @ptr: Destination address, in user space.
100	*
101	* Context: User context only. This function may sleep.
102	*
103	* This macro copies a single simple value from kernel space to user
104	* space. It supports simple types like char and int, but not larger
105	* data types like structures or arrays.
106	*
107	* @ptr must have pointer-to-simple-variable type, and @x must be assignable
108	* to the result of dereferencing @ptr.
109	*
110	* Caller must check the pointer with access_ok() before calling this
111	* function.
112	*
113	* Returns zero on success, or -EFAULT on error.
114	*/
115	#define __put_user(x, ptr) __put_user_nocheck((x), (ptr), sizeof(*(ptr)))
116
117	/*
118	* __get_user: - Get a simple variable from user space, with less checking.
119	* @x: Variable to store result.
120	* @ptr: Source address, in user space.
121	*
122	* Context: User context only. This function may sleep.
123	*
124	* This macro copies a single simple variable from user space to kernel
125	* space. It supports simple types like char and int, but not larger
126	* data types like structures or arrays.
127	*
128	* @ptr must have pointer-to-simple-variable type, and the result of
129	* dereferencing @ptr must be assignable to @x without a cast.
130	*
131	* Caller must check the pointer with access_ok() before calling this
132	* function.
133	*
134	* Returns zero on success, or -EFAULT on error.
135	* On error, the variable @x is set to zero.
136	*/
137	#define __get_user(x, ptr) __get_user_nocheck((x), (ptr), sizeof(*(ptr)))
138
139	struct __large_struct { unsigned long buf[100]; };
140	#define __m(x) ((struct __large_struct __user )(x))
141
142	/*
143	* Yuck. We need two variants, one for 64bit operation and one
144	* for 32 bit mode and old iron.
145	*/
146	extern void __get_user_unknown(void);
147
148	#define __get_user_common(val, size, ptr) \
149	do { \
150	switch (size) { \
151	case 1: \
152	__get_user_asm(val, "lb", ptr); \
153	break; \
154	case 2: \
155	__get_user_asm(val, "lh", ptr); \
156	break; \
157	case 4: \
158	__get_user_asm(val, "lw", ptr); \
159	break; \
160	case 8: \
60f0190e	161	if (__copy_from_user((void *)&val, ptr, 8) == 0) \
ffa818b4 CL	162	__gu_err = 0; \
	163	else \
	164	__gu_err = -EFAULT; \
	165	break; \
	166	default: \
	167	__get_user_unknown(); \
	168	break; \
	169	} \
	170	} while (0)
	171
	172	#define __get_user_nocheck(x, ptr, size) \
	173	({ \
	174	long __gu_err = 0; \
	175	__get_user_common((x), size, ptr); \
	176	__gu_err; \
	177	})
	178
	179	#define __get_user_check(x, ptr, size) \
	180	({ \
	181	long __gu_err = -EFAULT; \
	182	const __typeof__((ptr)) __user __gu_ptr = (ptr); \
	183	\
	184	if (likely(access_ok(VERIFY_READ, __gu_ptr, size))) \
	185	__get_user_common((x), size, __gu_ptr); \
60f0190e AV	186	else \
60f0190e AV	187	(x) = 0; \
ffa818b4 CL	188	\
	189	__gu_err; \
	190	})
	191
	192	#define __get_user_asm(val, insn, addr) \
	193	{ \
	194	long __gu_tmp; \
	195	\
	196	__asm__ __volatile__( \
	197	"1:" insn " %1, %3\n" \
	198	"2:\n" \
	199	".section .fixup,\"ax\"\n" \
	200	"3:li %0, %4\n" \
60f0190e	201	"li %1, 0\n" \
ffa818b4 CL	202	"j 2b\n" \
	203	".previous\n" \
	204	".section __ex_table,\"a\"\n" \
	205	".word 1b, 3b\n" \
	206	".previous\n" \
	207	: "=r" (__gu_err), "=r" (__gu_tmp) \
	208	: "0" (0), "o" (__m(addr)), "i" (-EFAULT)); \
	209	\
	210	(val) = (__typeof__(*(addr))) __gu_tmp; \
	211	}
	212
	213	/*
	214	* Yuck. We need two variants, one for 64bit operation and one
	215	* for 32 bit mode and old iron.
	216	*/
	217	#define __put_user_nocheck(val, ptr, size) \
	218	({ \
	219	__typeof__(*(ptr)) __pu_val; \
	220	long __pu_err = 0; \
	221	\
	222	__pu_val = (val); \
	223	switch (size) { \
	224	case 1: \
	225	__put_user_asm("sb", ptr); \
	226	break; \
	227	case 2: \
	228	__put_user_asm("sh", ptr); \
	229	break; \
	230	case 4: \
	231	__put_user_asm("sw", ptr); \
	232	break; \
	233	case 8: \
	234	if ((__copy_to_user((void *)ptr, &__pu_val, 8)) == 0) \
	235	__pu_err = 0; \
	236	else \
	237	__pu_err = -EFAULT; \
	238	break; \
	239	default: \
	240	__put_user_unknown(); \
	241	break; \
	242	} \
	243	__pu_err; \
	244	})
	245
	246
	247	#define __put_user_check(val, ptr, size) \
	248	({ \
	249	__typeof__((ptr)) __user __pu_addr = (ptr); \
	250	__typeof__(*(ptr)) __pu_val = (val); \
	251	long __pu_err = -EFAULT; \
	252	\
	253	if (likely(access_ok(VERIFY_WRITE, __pu_addr, size))) { \
	254	switch (size) { \
	255	case 1: \
	256	__put_user_asm("sb", __pu_addr); \
	257	break; \
	258	case 2: \
	259	__put_user_asm("sh", __pu_addr); \
	260	break; \
	261	case 4: \
	262	__put_user_asm("sw", __pu_addr); \
	263	break; \
	264	case 8: \
	265	if ((__copy_to_user((void *)__pu_addr, &__pu_val, 8)) == 0)\
266	__pu_err = 0; \
267	else \
268	__pu_err = -EFAULT; \
269	break; \
270	default: \
271	__put_user_unknown(); \
272	break; \
273	} \
274	} \
275	__pu_err; \
276	})
277
278	#define __put_user_asm(insn, ptr) \
279	__asm__ __volatile__( \
280	"1:" insn " %2, %3\n" \
281	"2:\n" \
282	".section .fixup,\"ax\"\n" \
283	"3:li %0, %4\n" \
284	"j 2b\n" \
285	".previous\n" \
286	".section __ex_table,\"a\"\n" \
287	".word 1b, 3b\n" \
288	".previous\n" \
289	: "=r" (__pu_err) \
290	: "0" (0), "r" (__pu_val), "o" (__m(ptr)), \
291	"i" (-EFAULT));
292
293	extern void __put_user_unknown(void);
294	extern int __copy_tofrom_user(void to, const void from, unsigned long len);
295
296	static inline unsigned long
297	copy_from_user(void to, const void from, unsigned long len)
298	{
a0c422b8	299	unsigned long res = len;
ffa818b4	300
a0c422b8 AV	301	if (likely(access_ok(VERIFY_READ, from, len)))
a0c422b8 AV	302	res = __copy_tofrom_user(to, from, len);
ffa818b4	303
a0c422b8 AV	304	if (unlikely(res))
	305	memset(to + (len - res), 0, res);
	306
	307	return res;
ffa818b4 CL	308	}
	309
	310	static inline unsigned long
	311	copy_to_user(void to, const void from, unsigned long len)
	312	{
a0c422b8 AV	313	if (likely(access_ok(VERIFY_WRITE, to, len)))
a0c422b8 AV	314	len = __copy_tofrom_user(to, from, len);
ffa818b4	315
ffa818b4 CL	316	return len;
ffa818b4 CL	317	}
6bc9a396	318
a0c422b8 AV	319	static inline unsigned long
	320	__copy_from_user(void to, const void from, unsigned long len)
	321	{
	322	unsigned long left = __copy_tofrom_user(to, from, len);
	323	if (unlikely(left))
	324	memset(to + (len - left), 0, left);
	325	return left;
	326	}
6bc9a396	327
ffa818b4 CL	328	#define __copy_to_user(to, from, len) \
ffa818b4 CL	329	__copy_tofrom_user((to), (from), (len))
6bc9a396	330
ffa818b4 CL	331	static inline unsigned long
	332	__copy_to_user_inatomic(void to, const void from, unsigned long len)
	333	{
	334	return __copy_to_user(to, from, len);
	335	}
6bc9a396	336
ffa818b4 CL	337	static inline unsigned long
	338	__copy_from_user_inatomic(void to, const void from, unsigned long len)
	339	{
a0c422b8	340	return __copy_tofrom_user(to, from, len);
ffa818b4 CL	341	}
ffa818b4 CL	342
a0c422b8	343	#define __copy_in_user(to, from, len) __copy_tofrom_user(to, from, len)
ffa818b4 CL	344
	345	static inline unsigned long
	346	copy_in_user(void to, const void from, unsigned long len)
	347	{
	348	if (access_ok(VERIFY_READ, from, len) &&
	349	access_ok(VERFITY_WRITE, to, len))
a0c422b8	350	return __copy_tofrom_user(to, from, len);
ffa818b4 CL	351	}
	352
	353	/*
	354	* __clear_user: - Zero a block of memory in user space, with less checking.
	355	* @to: Destination address, in user space.
	356	* @n: Number of bytes to zero.
	357	*
	358	* Zero a block of memory in user space. Caller must check
	359	* the specified block with access_ok() before calling this function.
	360	*
	361	* Returns number of bytes that could not be cleared.
	362	* On success, this will be zero.
	363	*/
	364	extern unsigned long __clear_user(void __user *src, unsigned long size);
	365
	366	static inline unsigned long clear_user(char *src, unsigned long size)
	367	{
	368	if (access_ok(VERIFY_WRITE, src, size))
	369	return __clear_user(src, size);
	370
	371	return -EFAULT;
	372	}
	373	/*
	374	* __strncpy_from_user: - Copy a NUL terminated string from userspace, with less checking.
	375	* @dst: Destination address, in kernel space. This buffer must be at
	376	* least @count bytes long.
	377	* @src: Source address, in user space.
	378	* @count: Maximum number of bytes to copy, including the trailing NUL.
	379	*
	380	* Copies a NUL-terminated string from userspace to kernel space.
	381	* Caller must check the specified block with access_ok() before calling
	382	* this function.
	383	*
	384	* On success, returns the length of the string (not including the trailing
	385	* NUL).
	386	*
	387	* If access to userspace fails, returns -EFAULT (some data may have been
	388	* copied).
	389	*
	390	* If @count is smaller than the length of the string, copies @count bytes
	391	* and returns @count.
	392	*/
	393	extern int __strncpy_from_user(char dst, const char src, long len);
	394
	395	static inline int strncpy_from_user(char dst, const char src, long len)
	396	{
	397	if (access_ok(VERIFY_READ, src, 1))
	398	return __strncpy_from_user(dst, src, len);
	399
	400	return -EFAULT;
	401	}
	402
	403	extern int __strlen_user(const char *src);
	404	static inline long strlen_user(const char __user *src)
	405	{
	406	return __strlen_user(src);
	407	}
	408
	409	extern int __strnlen_user(const char *str, long len);
	410	static inline long strnlen_user(const char __user *str, long len)
	411	{
	412	if (!access_ok(VERIFY_READ, str, 0))
	413	return 0;
	414	else
415	return __strnlen_user(str, len);
416	}
417
418	struct exception_table_entry {
419	unsigned long insn;
420	unsigned long fixup;
421	};
422
423	extern int fixup_exception(struct pt_regs *regs);
6bc9a396	424
ffa818b4	425	#endif /* __SCORE_UACCESS_H */
6bc9a396	426