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

/*
 *  arch/arm/include/asm/uaccess.h
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */
#ifndef _ASMARM_UACCESS_H
#define _ASMARM_UACCESS_H

/*
 * User space memory access functions
 */
#include <linux/string.h>
#include <asm/memory.h>
#include <asm/domain.h>
#include <asm/unified.h>
#include <asm/compiler.h>

#include <asm/extable.h>

/*
 * These two functions allow hooking accesses to userspace to increase
 * system integrity by ensuring that the kernel can not inadvertantly
 * perform such accesses (eg, via list poison values) which could then
 * be exploited for priviledge escalation.
 */
static inline unsigned int uaccess_save_and_enable(void)
{
#ifdef CONFIG_CPU_SW_DOMAIN_PAN
	unsigned int old_domain = get_domain();

	/* Set the current domain access to permit user accesses */
	set_domain((old_domain & ~domain_mask(DOMAIN_USER)) |
		   domain_val(DOMAIN_USER, DOMAIN_CLIENT));

	return old_domain;
#else
	return 0;
#endif
}

static inline void uaccess_restore(unsigned int flags)
{
#ifdef CONFIG_CPU_SW_DOMAIN_PAN
	/* Restore the user access mask */
	set_domain(flags);
#endif
}

/*
 * These two are intentionally not defined anywhere - if the kernel
 * code generates any references to them, that's a bug.
 */
extern int __get_user_bad(void);
extern int __put_user_bad(void);

/*
 * Note that this is actually 0x1,0000,0000
 */
#define KERNEL_DS	0x00000000
#define get_ds()	(KERNEL_DS)

#ifdef CONFIG_MMU

#define USER_DS		TASK_SIZE
#define get_fs()	(current_thread_info()->addr_limit)

static inline void set_fs(mm_segment_t fs)
{
	current_thread_info()->addr_limit = fs;
	modify_domain(DOMAIN_KERNEL, fs ? DOMAIN_CLIENT : DOMAIN_MANAGER);
}

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

/* We use 33-bit arithmetic here... */
#define __range_ok(addr, size) ({ \
	unsigned long flag, roksum; \
	__chk_user_ptr(addr);	\
	__asm__("adds %1, %2, %3; sbcccs %1, %1, %0; movcc %0, #0" \
		: "=&r" (flag), "=&r" (roksum) \
		: "r" (addr), "Ir" (size), "0" (current_thread_info()->addr_limit) \
		: "cc"); \
	flag; })

/*
 * Single-value transfer routines.  They automatically use the right
 * size if we just have the right pointer type.  Note that the functions
 * which read from user space (*get_*) need to take care not to leak
 * kernel data even if the calling code is buggy and fails to check
 * the return value.  This means zeroing out the destination variable
 * or buffer on error.  Normally this is done out of line by the
 * fixup code, but there are a few places where it intrudes on the
 * main code path.  When we only write to user space, there is no
 * problem.
 */
extern int __get_user_1(void *);
extern int __get_user_2(void *);
extern int __get_user_4(void *);
extern int __get_user_32t_8(void *);
extern int __get_user_8(void *);
extern int __get_user_64t_1(void *);
extern int __get_user_64t_2(void *);
extern int __get_user_64t_4(void *);

#define __GUP_CLOBBER_1	"lr", "cc"
#ifdef CONFIG_CPU_USE_DOMAINS
#define __GUP_CLOBBER_2	"ip", "lr", "cc"
#else
#define __GUP_CLOBBER_2 "lr", "cc"
#endif
#define __GUP_CLOBBER_4	"lr", "cc"
#define __GUP_CLOBBER_32t_8 "lr", "cc"
#define __GUP_CLOBBER_8	"lr", "cc"

#define __get_user_x(__r2, __p, __e, __l, __s)				\
	   __asm__ __volatile__ (					\
		__asmeq("%0", "r0") __asmeq("%1", "r2")			\
		__asmeq("%3", "r1")					\
		"bl	__get_user_" #__s				\
		: "=&r" (__e), "=r" (__r2)				\
		: "0" (__p), "r" (__l)					\
		: __GUP_CLOBBER_##__s)

/* narrowing a double-word get into a single 32bit word register: */
#ifdef __ARMEB__
#define __get_user_x_32t(__r2, __p, __e, __l, __s)			\
	__get_user_x(__r2, __p, __e, __l, 32t_8)
#else
#define __get_user_x_32t __get_user_x
#endif

/*
 * storing result into proper least significant word of 64bit target var,
 * different only for big endian case where 64 bit __r2 lsw is r3:
 */
#ifdef __ARMEB__
#define __get_user_x_64t(__r2, __p, __e, __l, __s)		        \
	   __asm__ __volatile__ (					\
		__asmeq("%0", "r0") __asmeq("%1", "r2")			\
		__asmeq("%3", "r1")					\
		"bl	__get_user_64t_" #__s				\
		: "=&r" (__e), "=r" (__r2)				\
		: "0" (__p), "r" (__l)					\
		: __GUP_CLOBBER_##__s)
#else
#define __get_user_x_64t __get_user_x
#endif


#define __get_user_check(x, p)						\
	({								\
		unsigned long __limit = current_thread_info()->addr_limit - 1; \
		register const typeof(*(p)) __user *__p asm("r0") = (p);\
		register typeof(x) __r2 asm("r2");			\
		register unsigned long __l asm("r1") = __limit;		\
		register int __e asm("r0");				\
		unsigned int __ua_flags = uaccess_save_and_enable();	\
		switch (sizeof(*(__p))) {				\
		case 1:							\
			if (sizeof((x)) >= 8)				\
				__get_user_x_64t(__r2, __p, __e, __l, 1); \
			else						\
				__get_user_x(__r2, __p, __e, __l, 1);	\
			break;						\
		case 2:							\
			if (sizeof((x)) >= 8)				\
				__get_user_x_64t(__r2, __p, __e, __l, 2); \
			else						\
				__get_user_x(__r2, __p, __e, __l, 2);	\
			break;						\
		case 4:							\
			if (sizeof((x)) >= 8)				\
				__get_user_x_64t(__r2, __p, __e, __l, 4); \
			else						\
				__get_user_x(__r2, __p, __e, __l, 4);	\
			break;						\
		case 8:							\
			if (sizeof((x)) < 8)				\
				__get_user_x_32t(__r2, __p, __e, __l, 4); \
			else						\
				__get_user_x(__r2, __p, __e, __l, 8);	\
			break;						\
		default: __e = __get_user_bad(); break;			\
		}							\
		uaccess_restore(__ua_flags);				\
		x = (typeof(*(p))) __r2;				\
		__e;							\
	})

#define get_user(x, p)							\
	({								\
		might_fault();						\
		__get_user_check(x, p);					\
	 })

extern int __put_user_1(void *, unsigned int);
extern int __put_user_2(void *, unsigned int);
extern int __put_user_4(void *, unsigned int);
extern int __put_user_8(void *, unsigned long long);

#define __put_user_check(__pu_val, __ptr, __err, __s)			\
	({								\
		unsigned long __limit = current_thread_info()->addr_limit - 1; \
		register typeof(__pu_val) __r2 asm("r2") = __pu_val;	\
		register const void __user *__p asm("r0") = __ptr;	\
		register unsigned long __l asm("r1") = __limit;		\
		register int __e asm("r0");				\
		__asm__ __volatile__ (					\
			__asmeq("%0", "r0") __asmeq("%2", "r2")		\
			__asmeq("%3", "r1")				\
			"bl	__put_user_" #__s			\
			: "=&r" (__e)					\
			: "0" (__p), "r" (__r2), "r" (__l)		\
			: "ip", "lr", "cc");				\
		__err = __e;						\
	})

#else /* CONFIG_MMU */

/*
 * uClinux has only one addr space, so has simplified address limits.
 */
#define USER_DS			KERNEL_DS

#define segment_eq(a, b)		(1)
#define __addr_ok(addr)		((void)(addr), 1)
#define __range_ok(addr, size)	((void)(addr), 0)
#define get_fs()		(KERNEL_DS)

static inline void set_fs(mm_segment_t fs)
{
}

#define get_user(x, p)	__get_user(x, p)
#define __put_user_check __put_user_nocheck

#endif /* CONFIG_MMU */

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

#define user_addr_max() \
	(uaccess_kernel() ? ~0UL : get_fs())

/*
 * The "__xxx" versions of the user access functions do not verify the
 * address space - it must have been done previously with a separate
 * "access_ok()" call.
 *
 * The "xxx_error" versions set the third argument to EFAULT if an
 * error occurs, and leave it unchanged on success.  Note that these
 * versions are void (ie, don't return a value as such).
 */
#define __get_user(x, ptr)						\
({									\
	long __gu_err = 0;						\
	__get_user_err((x), (ptr), __gu_err);				\
	__gu_err;							\
})

#define __get_user_error(x, ptr, err)					\
({									\
	__get_user_err((x), (ptr), err);				\
	(void) 0;							\
})

#define __get_user_err(x, ptr, err)					\
do {									\
	unsigned long __gu_addr = (unsigned long)(ptr);			\
	unsigned long __gu_val;						\
	unsigned int __ua_flags;					\
	__chk_user_ptr(ptr);						\
	might_fault();							\
	__ua_flags = uaccess_save_and_enable();				\
	switch (sizeof(*(ptr))) {					\
	case 1:	__get_user_asm_byte(__gu_val, __gu_addr, err);	break;	\
	case 2:	__get_user_asm_half(__gu_val, __gu_addr, err);	break;	\
	case 4:	__get_user_asm_word(__gu_val, __gu_addr, err);	break;	\
	default: (__gu_val) = __get_user_bad();				\
	}								\
	uaccess_restore(__ua_flags);					\
	(x) = (__typeof__(*(ptr)))__gu_val;				\
} while (0)

#define __get_user_asm(x, addr, err, instr)			\
	__asm__ __volatile__(					\
	"1:	" TUSER(instr) " %1, [%2], #0\n"		\
	"2:\n"							\
	"	.pushsection .text.fixup,\"ax\"\n"		\
	"	.align	2\n"					\
	"3:	mov	%0, %3\n"				\
	"	mov	%1, #0\n"				\
	"	b	2b\n"					\
	"	.popsection\n"					\
	"	.pushsection __ex_table,\"a\"\n"		\
	"	.align	3\n"					\
	"	.long	1b, 3b\n"				\
	"	.popsection"					\
	: "+r" (err), "=&r" (x)					\
	: "r" (addr), "i" (-EFAULT)				\
	: "cc")

#define __get_user_asm_byte(x, addr, err)			\
	__get_user_asm(x, addr, err, ldrb)

#ifndef __ARMEB__
#define __get_user_asm_half(x, __gu_addr, err)			\
({								\
	unsigned long __b1, __b2;				\
	__get_user_asm_byte(__b1, __gu_addr, err);		\
	__get_user_asm_byte(__b2, __gu_addr + 1, err);		\
	(x) = __b1 | (__b2 << 8);				\
})
#else
#define __get_user_asm_half(x, __gu_addr, err)			\
({								\
	unsigned long __b1, __b2;				\
	__get_user_asm_byte(__b1, __gu_addr, err);		\
	__get_user_asm_byte(__b2, __gu_addr + 1, err);		\
	(x) = (__b1 << 8) | __b2;				\
})
#endif

#define __get_user_asm_word(x, addr, err)			\
	__get_user_asm(x, addr, err, ldr)


#define __put_user_switch(x, ptr, __err, __fn)				\
	do {								\
		const __typeof__(*(ptr)) __user *__pu_ptr = (ptr);	\
		__typeof__(*(ptr)) __pu_val = (x);			\
		unsigned int __ua_flags;				\
		might_fault();						\
		__ua_flags = uaccess_save_and_enable();			\
		switch (sizeof(*(ptr))) {				\
		case 1: __fn(__pu_val, __pu_ptr, __err, 1); break;	\
		case 2:	__fn(__pu_val, __pu_ptr, __err, 2); break;	\
		case 4:	__fn(__pu_val, __pu_ptr, __err, 4); break;	\
		case 8:	__fn(__pu_val, __pu_ptr, __err, 8); break;	\
		default: __err = __put_user_bad(); break;		\
		}							\
		uaccess_restore(__ua_flags);				\
	} while (0)

#define put_user(x, ptr)						\
({									\
	int __pu_err = 0;						\
	__put_user_switch((x), (ptr), __pu_err, __put_user_check);	\
	__pu_err;							\
})

#define __put_user(x, ptr)						\
({									\
	long __pu_err = 0;						\
	__put_user_switch((x), (ptr), __pu_err, __put_user_nocheck);	\
	__pu_err;							\
})

#define __put_user_error(x, ptr, err)					\
({									\
	__put_user_switch((x), (ptr), (err), __put_user_nocheck);	\
	(void) 0;							\
})

#define __put_user_nocheck(x, __pu_ptr, __err, __size)			\
	do {								\
		unsigned long __pu_addr = (unsigned long)__pu_ptr;	\
		__put_user_nocheck_##__size(x, __pu_addr, __err);	\
	} while (0)

#define __put_user_nocheck_1 __put_user_asm_byte
#define __put_user_nocheck_2 __put_user_asm_half
#define __put_user_nocheck_4 __put_user_asm_word
#define __put_user_nocheck_8 __put_user_asm_dword

#define __put_user_asm(x, __pu_addr, err, instr)		\
	__asm__ __volatile__(					\
	"1:	" TUSER(instr) " %1, [%2], #0\n"		\
	"2:\n"							\
	"	.pushsection .text.fixup,\"ax\"\n"		\
	"	.align	2\n"					\
	"3:	mov	%0, %3\n"				\
	"	b	2b\n"					\
	"	.popsection\n"					\
	"	.pushsection __ex_table,\"a\"\n"		\
	"	.align	3\n"					\
	"	.long	1b, 3b\n"				\
	"	.popsection"					\
	: "+r" (err)						\
	: "r" (x), "r" (__pu_addr), "i" (-EFAULT)		\
	: "cc")

#define __put_user_asm_byte(x, __pu_addr, err)			\
	__put_user_asm(x, __pu_addr, err, strb)

#ifndef __ARMEB__
#define __put_user_asm_half(x, __pu_addr, err)			\
({								\
	unsigned long __temp = (__force unsigned long)(x);	\
	__put_user_asm_byte(__temp, __pu_addr, err);		\
	__put_user_asm_byte(__temp >> 8, __pu_addr + 1, err);	\
})
#else
#define __put_user_asm_half(x, __pu_addr, err)			\
({								\
	unsigned long __temp = (__force unsigned long)(x);	\
	__put_user_asm_byte(__temp >> 8, __pu_addr, err);	\
	__put_user_asm_byte(__temp, __pu_addr + 1, err);	\
})
#endif

#define __put_user_asm_word(x, __pu_addr, err)			\
	__put_user_asm(x, __pu_addr, err, str)

#ifndef __ARMEB__
#define	__reg_oper0	"%R2"
#define	__reg_oper1	"%Q2"
#else
#define	__reg_oper0	"%Q2"
#define	__reg_oper1	"%R2"
#endif

#define __put_user_asm_dword(x, __pu_addr, err)			\
	__asm__ __volatile__(					\
 ARM(	"1:	" TUSER(str) "	" __reg_oper1 ", [%1], #4\n"	) \
 ARM(	"2:	" TUSER(str) "	" __reg_oper0 ", [%1]\n"	) \
 THUMB(	"1:	" TUSER(str) "	" __reg_oper1 ", [%1]\n"	) \
 THUMB(	"2:	" TUSER(str) "	" __reg_oper0 ", [%1, #4]\n"	) \
	"3:\n"							\
	"	.pushsection .text.fixup,\"ax\"\n"		\
	"	.align	2\n"					\
	"4:	mov	%0, %3\n"				\
	"	b	3b\n"					\
	"	.popsection\n"					\
	"	.pushsection __ex_table,\"a\"\n"		\
	"	.align	3\n"					\
	"	.long	1b, 4b\n"				\
	"	.long	2b, 4b\n"				\
	"	.popsection"					\
	: "+r" (err), "+r" (__pu_addr)				\
	: "r" (x), "i" (-EFAULT)				\
	: "cc")


#ifdef CONFIG_MMU
extern unsigned long __must_check
arm_copy_from_user(void *to, const void __user *from, unsigned long n);

static inline unsigned long __must_check
raw_copy_from_user(void *to, const void __user *from, unsigned long n)
{
	unsigned int __ua_flags;

	__ua_flags = uaccess_save_and_enable();
	n = arm_copy_from_user(to, from, n);
	uaccess_restore(__ua_flags);
	return n;
}

extern unsigned long __must_check
arm_copy_to_user(void __user *to, const void *from, unsigned long n);
extern unsigned long __must_check
__copy_to_user_std(void __user *to, const void *from, unsigned long n);

static inline unsigned long __must_check
raw_copy_to_user(void __user *to, const void *from, unsigned long n)
{
#ifndef CONFIG_UACCESS_WITH_MEMCPY
	unsigned int __ua_flags;
	__ua_flags = uaccess_save_and_enable();
	n = arm_copy_to_user(to, from, n);
	uaccess_restore(__ua_flags);
	return n;
#else
	return arm_copy_to_user(to, from, n);
#endif
}

extern unsigned long __must_check
arm_clear_user(void __user *addr, unsigned long n);
extern unsigned long __must_check
__clear_user_std(void __user *addr, unsigned long n);

static inline unsigned long __must_check
__clear_user(void __user *addr, unsigned long n)
{
	unsigned int __ua_flags = uaccess_save_and_enable();
	n = arm_clear_user(addr, n);
	uaccess_restore(__ua_flags);
	return n;
}

#else
static inline unsigned long
raw_copy_from_user(void *to, const void __user *from, unsigned long n)
{
	memcpy(to, (const void __force *)from, n);
	return 0;
}
static inline unsigned long
raw_copy_to_user(void __user *to, const void *from, unsigned long n)
{
	memcpy((void __force *)to, from, n);
	return 0;
}
#define __clear_user(addr, n)		(memset((void __force *)addr, 0, n), 0)
#endif
#define INLINE_COPY_TO_USER
#define INLINE_COPY_FROM_USER

static inline unsigned long __must_check clear_user(void __user *to, unsigned long n)
{
	if (access_ok(VERIFY_WRITE, to, n))
		n = __clear_user(to, n);
	return n;
}

/* These are from lib/ code, and use __get_user() and friends */
extern long strncpy_from_user(char *dest, const char __user *src, long count);

extern __must_check long strnlen_user(const char __user *str, long n);

#endif /* _ASMARM_UACCESS_H */
Commit	Line	Data
1da177e4	1	/*
4baa9922	2	* arch/arm/include/asm/uaccess.h
1da177e4 LT	3	*
	4	* This program is free software; you can redistribute it and/or modify
	5	* it under the terms of the GNU General Public License version 2 as
	6	* published by the Free Software Foundation.
	7	*/
	8	#ifndef _ASMARM_UACCESS_H
	9	#define _ASMARM_UACCESS_H
	10
	11	/*
	12	* User space memory access functions
	13	*/
87c52578	14	#include <linux/string.h>
1da177e4 LT	15	#include <asm/memory.h>
1da177e4 LT	16	#include <asm/domain.h>
8b592783	17	#include <asm/unified.h>
9f97da78	18	#include <asm/compiler.h>
1da177e4	19
0f9b38cd	20	#include <asm/extable.h>
1da177e4	21
3fba7e23 RK	22	/*
	23	* These two functions allow hooking accesses to userspace to increase
	24	* system integrity by ensuring that the kernel can not inadvertantly
	25	* perform such accesses (eg, via list poison values) which could then
	26	* be exploited for priviledge escalation.
	27	*/
	28	static inline unsigned int uaccess_save_and_enable(void)
	29	{
a5e090ac RK	30	#ifdef CONFIG_CPU_SW_DOMAIN_PAN
	31	unsigned int old_domain = get_domain();
	32
	33	/* Set the current domain access to permit user accesses */
	34	set_domain((old_domain & ~domain_mask(DOMAIN_USER)) \|
	35	domain_val(DOMAIN_USER, DOMAIN_CLIENT));
	36
	37	return old_domain;
	38	#else
3fba7e23	39	return 0;
a5e090ac	40	#endif
3fba7e23 RK	41	}
	42
	43	static inline void uaccess_restore(unsigned int flags)
	44	{
a5e090ac RK	45	#ifdef CONFIG_CPU_SW_DOMAIN_PAN
	46	/* Restore the user access mask */
	47	set_domain(flags);
	48	#endif
3fba7e23 RK	49	}
3fba7e23 RK	50
9641c7cc RK	51	/*
	52	* These two are intentionally not defined anywhere - if the kernel
	53	* code generates any references to them, that's a bug.
	54	*/
	55	extern int __get_user_bad(void);
	56	extern int __put_user_bad(void);
	57
1da177e4 LT	58	/*
	59	* Note that this is actually 0x1,0000,0000
	60	*/
	61	#define KERNEL_DS 0x00000000
1da177e4	62	#define get_ds() (KERNEL_DS)
9641c7cc RK	63
	64	#ifdef CONFIG_MMU
	65
	66	#define USER_DS TASK_SIZE
1da177e4 LT	67	#define get_fs() (current_thread_info()->addr_limit)
1da177e4 LT	68
9641c7cc	69	static inline void set_fs(mm_segment_t fs)
1da177e4 LT	70	{
	71	current_thread_info()->addr_limit = fs;
	72	modify_domain(DOMAIN_KERNEL, fs ? DOMAIN_CLIENT : DOMAIN_MANAGER);
	73	}
	74
295bb01e	75	#define segment_eq(a, b) ((a) == (b))
1da177e4	76
1da177e4	77	/* We use 33-bit arithmetic here... */
295bb01e	78	#define __range_ok(addr, size) ({ \
16cf5b39	79	unsigned long flag, roksum; \
1da177e4 LT	80	__chk_user_ptr(addr); \
1da177e4 LT	81	__asm__("adds %1, %2, %3; sbcccs %1, %1, %0; movcc %0, #0" \
16cf5b39	82	: "=&r" (flag), "=&r" (roksum) \
1da177e4 LT	83	: "r" (addr), "Ir" (size), "0" (current_thread_info()->addr_limit) \
	84	: "cc"); \
	85	flag; })
	86
1da177e4 LT	87	/*
	88	* Single-value transfer routines. They automatically use the right
	89	* size if we just have the right pointer type. Note that the functions
	90	* which read from user space (get_) need to take care not to leak
	91	* kernel data even if the calling code is buggy and fails to check
	92	* the return value. This means zeroing out the destination variable
	93	* or buffer on error. Normally this is done out of line by the
	94	* fixup code, but there are a few places where it intrudes on the
	95	* main code path. When we only write to user space, there is no
	96	* problem.
1da177e4	97	*/
1da177e4 LT	98	extern int __get_user_1(void *);
	99	extern int __get_user_2(void *);
	100	extern int __get_user_4(void *);
d9981380	101	extern int __get_user_32t_8(void *);
e38361d0	102	extern int __get_user_8(void *);
d9981380 VK	103	extern int __get_user_64t_1(void *);
	104	extern int __get_user_64t_2(void *);
	105	extern int __get_user_64t_4(void *);
1da177e4	106
8404663f RK	107	#define __GUP_CLOBBER_1 "lr", "cc"
	108	#ifdef CONFIG_CPU_USE_DOMAINS
	109	#define __GUP_CLOBBER_2 "ip", "lr", "cc"
	110	#else
	111	#define __GUP_CLOBBER_2 "lr", "cc"
	112	#endif
	113	#define __GUP_CLOBBER_4 "lr", "cc"
d9981380	114	#define __GUP_CLOBBER_32t_8 "lr", "cc"
e38361d0	115	#define __GUP_CLOBBER_8 "lr", "cc"
8404663f	116
295bb01e	117	#define __get_user_x(__r2, __p, __e, __l, __s) \
1da177e4 LT	118	__asm__ __volatile__ ( \
1da177e4 LT	119	__asmeq("%0", "r0") __asmeq("%1", "r2") \
8404663f	120	__asmeq("%3", "r1") \
1da177e4 LT	121	"bl __get_user_" #__s \
1da177e4 LT	122	: "=&r" (__e), "=r" (__r2) \
8404663f RK	123	: "0" (__p), "r" (__l) \
8404663f RK	124	: __GUP_CLOBBER_##__s)
1da177e4	125
e38361d0 DT	126	/* narrowing a double-word get into a single 32bit word register: */
e38361d0 DT	127	#ifdef __ARMEB__
295bb01e	128	#define __get_user_x_32t(__r2, __p, __e, __l, __s) \
d9981380	129	__get_user_x(__r2, __p, __e, __l, 32t_8)
e38361d0	130	#else
d9981380	131	#define __get_user_x_32t __get_user_x
e38361d0 DT	132	#endif
e38361d0 DT	133
d9981380 VK	134	/*
	135	* storing result into proper least significant word of 64bit target var,
	136	* different only for big endian case where 64 bit __r2 lsw is r3:
	137	*/
	138	#ifdef __ARMEB__
	139	#define __get_user_x_64t(__r2, __p, __e, __l, __s) \
	140	__asm__ __volatile__ ( \
	141	__asmeq("%0", "r0") __asmeq("%1", "r2") \
	142	__asmeq("%3", "r1") \
	143	"bl __get_user_64t_" #__s \
	144	: "=&r" (__e), "=r" (__r2) \
	145	: "0" (__p), "r" (__l) \
	146	: __GUP_CLOBBER_##__s)
	147	#else
	148	#define __get_user_x_64t __get_user_x
	149	#endif
	150
	151
295bb01e	152	#define __get_user_check(x, p) \
1da177e4	153	({ \
8404663f	154	unsigned long __limit = current_thread_info()->addr_limit - 1; \
c5a69d57	155	register const typeof((p)) __user __p asm("r0") = (p);\
e38361d0	156	register typeof(x) __r2 asm("r2"); \
8404663f	157	register unsigned long __l asm("r1") = __limit; \
1da177e4	158	register int __e asm("r0"); \
3fba7e23	159	unsigned int __ua_flags = uaccess_save_and_enable(); \
1da177e4 LT	160	switch (sizeof(*(__p))) { \
1da177e4 LT	161	case 1: \
d9981380 VK	162	if (sizeof((x)) >= 8) \
	163	__get_user_x_64t(__r2, __p, __e, __l, 1); \
	164	else \
	165	__get_user_x(__r2, __p, __e, __l, 1); \
8404663f	166	break; \
1da177e4	167	case 2: \
d9981380 VK	168	if (sizeof((x)) >= 8) \
	169	__get_user_x_64t(__r2, __p, __e, __l, 2); \
	170	else \
	171	__get_user_x(__r2, __p, __e, __l, 2); \
1da177e4 LT	172	break; \
1da177e4 LT	173	case 4: \
d9981380 VK	174	if (sizeof((x)) >= 8) \
	175	__get_user_x_64t(__r2, __p, __e, __l, 4); \
	176	else \
	177	__get_user_x(__r2, __p, __e, __l, 4); \
1da177e4	178	break; \
e38361d0 DT	179	case 8: \
e38361d0 DT	180	if (sizeof((x)) < 8) \
d9981380	181	__get_user_x_32t(__r2, __p, __e, __l, 4); \
e38361d0 DT	182	else \
	183	__get_user_x(__r2, __p, __e, __l, 8); \
	184	break; \
1da177e4 LT	185	default: __e = __get_user_bad(); break; \
1da177e4 LT	186	} \
3fba7e23	187	uaccess_restore(__ua_flags); \
d2c5b690	188	x = (typeof(*(p))) __r2; \
1da177e4 LT	189	__e; \
	190	})
	191
295bb01e	192	#define get_user(x, p) \
ad72907a WD	193	({ \
ad72907a WD	194	might_fault(); \
295bb01e	195	__get_user_check(x, p); \
ad72907a WD	196	})
ad72907a WD	197
9641c7cc RK	198	extern int __put_user_1(void *, unsigned int);
	199	extern int __put_user_2(void *, unsigned int);
	200	extern int __put_user_4(void *, unsigned int);
	201	extern int __put_user_8(void *, unsigned long long);
	202
9f73bd8b	203	#define __put_user_check(__pu_val, __ptr, __err, __s) \
9641c7cc	204	({ \
8404663f	205	unsigned long __limit = current_thread_info()->addr_limit - 1; \
9f73bd8b RK	206	register typeof(__pu_val) __r2 asm("r2") = __pu_val; \
9f73bd8b RK	207	register const void __user *__p asm("r0") = __ptr; \
8404663f	208	register unsigned long __l asm("r1") = __limit; \
9641c7cc	209	register int __e asm("r0"); \
9f73bd8b RK	210	__asm__ __volatile__ ( \
	211	__asmeq("%0", "r0") __asmeq("%2", "r2") \
	212	__asmeq("%3", "r1") \
	213	"bl __put_user_" #__s \
	214	: "=&r" (__e) \
	215	: "0" (__p), "r" (__r2), "r" (__l) \
	216	: "ip", "lr", "cc"); \
	217	__err = __e; \
9641c7cc RK	218	})
	219
	220	#else /* CONFIG_MMU */
	221
	222	/*
	223	* uClinux has only one addr space, so has simplified address limits.
	224	*/
	225	#define USER_DS KERNEL_DS
	226
295bb01e MT	227	#define segment_eq(a, b) (1)
	228	#define __addr_ok(addr) ((void)(addr), 1)
	229	#define __range_ok(addr, size) ((void)(addr), 0)
9641c7cc RK	230	#define get_fs() (KERNEL_DS)
	231
	232	static inline void set_fs(mm_segment_t fs)
	233	{
	234	}
	235
295bb01e	236	#define get_user(x, p) __get_user(x, p)
9f73bd8b	237	#define __put_user_check __put_user_nocheck
9641c7cc RK	238
	239	#endif /* CONFIG_MMU */
	240
295bb01e	241	#define access_ok(type, addr, size) (__range_ok(addr, size) == 0)
9641c7cc	242
8c56cc8b	243	#define user_addr_max() \
db68ce10	244	(uaccess_kernel() ? ~0UL : get_fs())
8c56cc8b	245
9641c7cc RK	246	/*
	247	* The "__xxx" versions of the user access functions do not verify the
	248	* address space - it must have been done previously with a separate
	249	* "access_ok()" call.
	250	*
	251	* The "xxx_error" versions set the third argument to EFAULT if an
	252	* error occurs, and leave it unchanged on success. Note that these
	253	* versions are void (ie, don't return a value as such).
	254	*/
295bb01e	255	#define __get_user(x, ptr) \
1da177e4 LT	256	({ \
1da177e4 LT	257	long __gu_err = 0; \
295bb01e	258	__get_user_err((x), (ptr), __gu_err); \
1da177e4 LT	259	__gu_err; \
	260	})
	261
295bb01e	262	#define __get_user_error(x, ptr, err) \
1da177e4	263	({ \
295bb01e	264	__get_user_err((x), (ptr), err); \
1da177e4 LT	265	(void) 0; \
	266	})
	267
295bb01e	268	#define __get_user_err(x, ptr, err) \
1da177e4 LT	269	do { \
	270	unsigned long __gu_addr = (unsigned long)(ptr); \
	271	unsigned long __gu_val; \
3fba7e23	272	unsigned int __ua_flags; \
1da177e4	273	__chk_user_ptr(ptr); \
ad72907a	274	might_fault(); \
3fba7e23	275	__ua_flags = uaccess_save_and_enable(); \
1da177e4	276	switch (sizeof(*(ptr))) { \
295bb01e MT	277	case 1: __get_user_asm_byte(__gu_val, __gu_addr, err); break; \
	278	case 2: __get_user_asm_half(__gu_val, __gu_addr, err); break; \
	279	case 4: __get_user_asm_word(__gu_val, __gu_addr, err); break; \
1da177e4 LT	280	default: (__gu_val) = __get_user_bad(); \
1da177e4 LT	281	} \
3fba7e23	282	uaccess_restore(__ua_flags); \
1da177e4 LT	283	(x) = (__typeof__(*(ptr)))__gu_val; \
	284	} while (0)
	285
b64d1f66	286	#define __get_user_asm(x, addr, err, instr) \
1da177e4	287	__asm__ __volatile__( \
b64d1f66	288	"1: " TUSER(instr) " %1, [%2], #0\n" \
1da177e4	289	"2:\n" \
c4a84ae3	290	" .pushsection .text.fixup,\"ax\"\n" \
1da177e4 LT	291	" .align 2\n" \
	292	"3: mov %0, %3\n" \
	293	" mov %1, #0\n" \
	294	" b 2b\n" \
4260415f RK	295	" .popsection\n" \
4260415f RK	296	" .pushsection __ex_table,\"a\"\n" \
1da177e4 LT	297	" .align 3\n" \
1da177e4 LT	298	" .long 1b, 3b\n" \
4260415f	299	" .popsection" \
1da177e4 LT	300	: "+r" (err), "=&r" (x) \
	301	: "r" (addr), "i" (-EFAULT) \
	302	: "cc")
	303
b64d1f66 RK	304	#define __get_user_asm_byte(x, addr, err) \
	305	__get_user_asm(x, addr, err, ldrb)
	306
1da177e4	307	#ifndef __ARMEB__
295bb01e	308	#define __get_user_asm_half(x, __gu_addr, err) \
1da177e4 LT	309	({ \
	310	unsigned long __b1, __b2; \
	311	__get_user_asm_byte(__b1, __gu_addr, err); \
	312	__get_user_asm_byte(__b2, __gu_addr + 1, err); \
	313	(x) = __b1 \| (__b2 << 8); \
	314	})
	315	#else
295bb01e	316	#define __get_user_asm_half(x, __gu_addr, err) \
1da177e4 LT	317	({ \
	318	unsigned long __b1, __b2; \
	319	__get_user_asm_byte(__b1, __gu_addr, err); \
	320	__get_user_asm_byte(__b2, __gu_addr + 1, err); \
	321	(x) = (__b1 << 8) \| __b2; \
	322	})
	323	#endif
	324
295bb01e	325	#define __get_user_asm_word(x, addr, err) \
b64d1f66	326	__get_user_asm(x, addr, err, ldr)
1da177e4	327
9f73bd8b RK	328
	329	#define __put_user_switch(x, ptr, __err, __fn) \
	330	do { \
	331	const __typeof__((ptr)) __user __pu_ptr = (ptr); \
	332	__typeof__(*(ptr)) __pu_val = (x); \
	333	unsigned int __ua_flags; \
	334	might_fault(); \
	335	__ua_flags = uaccess_save_and_enable(); \
	336	switch (sizeof(*(ptr))) { \
	337	case 1: __fn(__pu_val, __pu_ptr, __err, 1); break; \
	338	case 2: __fn(__pu_val, __pu_ptr, __err, 2); break; \
	339	case 4: __fn(__pu_val, __pu_ptr, __err, 4); break; \
	340	case 8: __fn(__pu_val, __pu_ptr, __err, 8); break; \
	341	default: __err = __put_user_bad(); break; \
	342	} \
	343	uaccess_restore(__ua_flags); \
	344	} while (0)
	345
	346	#define put_user(x, ptr) \
	347	({ \
	348	int __pu_err = 0; \
	349	__put_user_switch((x), (ptr), __pu_err, __put_user_check); \
	350	__pu_err; \
	351	})
	352
295bb01e	353	#define __put_user(x, ptr) \
1da177e4 LT	354	({ \
1da177e4 LT	355	long __pu_err = 0; \
9f73bd8b	356	__put_user_switch((x), (ptr), __pu_err, __put_user_nocheck); \
1da177e4 LT	357	__pu_err; \
	358	})
	359
295bb01e	360	#define __put_user_error(x, ptr, err) \
1da177e4	361	({ \
9f73bd8b	362	__put_user_switch((x), (ptr), (err), __put_user_nocheck); \
1da177e4 LT	363	(void) 0; \
	364	})
	365
9f73bd8b RK	366	#define __put_user_nocheck(x, __pu_ptr, __err, __size) \
	367	do { \
	368	unsigned long __pu_addr = (unsigned long)__pu_ptr; \
	369	__put_user_nocheck_##__size(x, __pu_addr, __err); \
	370	} while (0)
	371
	372	#define __put_user_nocheck_1 __put_user_asm_byte
	373	#define __put_user_nocheck_2 __put_user_asm_half
	374	#define __put_user_nocheck_4 __put_user_asm_word
	375	#define __put_user_nocheck_8 __put_user_asm_dword
1da177e4	376
b64d1f66	377	#define __put_user_asm(x, __pu_addr, err, instr) \
1da177e4	378	__asm__ __volatile__( \
b64d1f66	379	"1: " TUSER(instr) " %1, [%2], #0\n" \
1da177e4	380	"2:\n" \
c4a84ae3	381	" .pushsection .text.fixup,\"ax\"\n" \
1da177e4 LT	382	" .align 2\n" \
	383	"3: mov %0, %3\n" \
	384	" b 2b\n" \
4260415f RK	385	" .popsection\n" \
4260415f RK	386	" .pushsection __ex_table,\"a\"\n" \
1da177e4 LT	387	" .align 3\n" \
1da177e4 LT	388	" .long 1b, 3b\n" \
4260415f	389	" .popsection" \
1da177e4 LT	390	: "+r" (err) \
	391	: "r" (x), "r" (__pu_addr), "i" (-EFAULT) \
	392	: "cc")
	393
b64d1f66 RK	394	#define __put_user_asm_byte(x, __pu_addr, err) \
	395	__put_user_asm(x, __pu_addr, err, strb)
	396
1da177e4	397	#ifndef __ARMEB__
295bb01e	398	#define __put_user_asm_half(x, __pu_addr, err) \
1da177e4	399	({ \
e8b94dea	400	unsigned long __temp = (__force unsigned long)(x); \
1da177e4 LT	401	__put_user_asm_byte(__temp, __pu_addr, err); \
	402	__put_user_asm_byte(__temp >> 8, __pu_addr + 1, err); \
	403	})
	404	#else
295bb01e	405	#define __put_user_asm_half(x, __pu_addr, err) \
1da177e4	406	({ \
e8b94dea	407	unsigned long __temp = (__force unsigned long)(x); \
1da177e4 LT	408	__put_user_asm_byte(__temp >> 8, __pu_addr, err); \
	409	__put_user_asm_byte(__temp, __pu_addr + 1, err); \
	410	})
	411	#endif
	412
295bb01e	413	#define __put_user_asm_word(x, __pu_addr, err) \
b64d1f66	414	__put_user_asm(x, __pu_addr, err, str)
1da177e4 LT	415
	416	#ifndef __ARMEB__
	417	#define __reg_oper0 "%R2"
	418	#define __reg_oper1 "%Q2"
	419	#else
	420	#define __reg_oper0 "%Q2"
	421	#define __reg_oper1 "%R2"
	422	#endif
	423
295bb01e	424	#define __put_user_asm_dword(x, __pu_addr, err) \
1da177e4	425	__asm__ __volatile__( \
4e7682d0 CM	426	ARM( "1: " TUSER(str) " " __reg_oper1 ", [%1], #4\n" ) \
	427	ARM( "2: " TUSER(str) " " __reg_oper0 ", [%1]\n" ) \
	428	THUMB( "1: " TUSER(str) " " __reg_oper1 ", [%1]\n" ) \
	429	THUMB( "2: " TUSER(str) " " __reg_oper0 ", [%1, #4]\n" ) \
1da177e4	430	"3:\n" \
c4a84ae3	431	" .pushsection .text.fixup,\"ax\"\n" \
1da177e4 LT	432	" .align 2\n" \
	433	"4: mov %0, %3\n" \
	434	" b 3b\n" \
4260415f RK	435	" .popsection\n" \
4260415f RK	436	" .pushsection __ex_table,\"a\"\n" \
1da177e4 LT	437	" .align 3\n" \
	438	" .long 1b, 4b\n" \
	439	" .long 2b, 4b\n" \
4260415f	440	" .popsection" \
1da177e4 LT	441	: "+r" (err), "+r" (__pu_addr) \
	442	: "r" (x), "i" (-EFAULT) \
	443	: "cc")
	444
02fcb974	445
9641c7cc	446	#ifdef CONFIG_MMU
3fba7e23 RK	447	extern unsigned long __must_check
	448	arm_copy_from_user(void to, const void __user from, unsigned long n);
	449
	450	static inline unsigned long __must_check
4de5b63e	451	raw_copy_from_user(void to, const void __user from, unsigned long n)
3fba7e23	452	{
dfd45b61 KC	453	unsigned int __ua_flags;
dfd45b61 KC	454
dfd45b61	455	__ua_flags = uaccess_save_and_enable();
3fba7e23 RK	456	n = arm_copy_from_user(to, from, n);
	457	uaccess_restore(__ua_flags);
	458	return n;
	459	}
	460
	461	extern unsigned long __must_check
	462	arm_copy_to_user(void __user to, const void from, unsigned long n);
	463	extern unsigned long __must_check
	464	__copy_to_user_std(void __user to, const void from, unsigned long n);
	465
	466	static inline unsigned long __must_check
4de5b63e	467	raw_copy_to_user(void __user to, const void from, unsigned long n)
3fba7e23	468	{
c014953d	469	#ifndef CONFIG_UACCESS_WITH_MEMCPY
dfd45b61	470	unsigned int __ua_flags;
dfd45b61	471	__ua_flags = uaccess_save_and_enable();
3fba7e23 RK	472	n = arm_copy_to_user(to, from, n);
	473	uaccess_restore(__ua_flags);
	474	return n;
c014953d RK	475	#else
	476	return arm_copy_to_user(to, from, n);
	477	#endif
3fba7e23 RK	478	}
	479
	480	extern unsigned long __must_check
	481	arm_clear_user(void __user *addr, unsigned long n);
	482	extern unsigned long __must_check
	483	__clear_user_std(void __user *addr, unsigned long n);
	484
	485	static inline unsigned long __must_check
	486	__clear_user(void __user *addr, unsigned long n)
	487	{
	488	unsigned int __ua_flags = uaccess_save_and_enable();
	489	n = arm_clear_user(addr, n);
	490	uaccess_restore(__ua_flags);
	491	return n;
	492	}
	493
9641c7cc	494	#else
4de5b63e AV	495	static inline unsigned long
4de5b63e AV	496	raw_copy_from_user(void to, const void __user from, unsigned long n)
32b14363	497	{
4de5b63e AV	498	memcpy(to, (const void __force *)from, n);
4de5b63e AV	499	return 0;
32b14363	500	}
4de5b63e AV	501	static inline unsigned long
4de5b63e AV	502	raw_copy_to_user(void __user to, const void from, unsigned long n)
32b14363	503	{
4de5b63e AV	504	memcpy((void __force *)to, from, n);
4de5b63e AV	505	return 0;
1da177e4	506	}
4de5b63e AV	507	#define __clear_user(addr, n) (memset((void __force *)addr, 0, n), 0)
	508	#endif
	509	#define INLINE_COPY_TO_USER
	510	#define INLINE_COPY_FROM_USER
1da177e4	511
99573298	512	static inline unsigned long __must_check clear_user(void __user *to, unsigned long n)
1da177e4 LT	513	{
1da177e4 LT	514	if (access_ok(VERIFY_WRITE, to, n))
02fcb974	515	n = __clear_user(to, n);
1da177e4 LT	516	return n;
	517	}
	518
3fba7e23	519	/* These are from lib/ code, and use __get_user() and friends */
8c56cc8b	520	extern long strncpy_from_user(char dest, const char __user src, long count);
1da177e4	521
8c56cc8b	522	extern __must_check long strnlen_user(const char __user *str, long n);
1da177e4 LT	523
1da177e4 LT	524	#endif /* _ASMARM_UACCESS_H */