[mirror_ubuntu-artful-kernel.git] / arch / x86 / include / asm / uaccess.h

#ifndef _ASM_X86_UACCESS_H
#define _ASM_X86_UACCESS_H
/*
 * User space memory access functions
 */
#include <linux/errno.h>
#include <linux/compiler.h>
#include <linux/thread_info.h>
#include <linux/string.h>
#include <asm/asm.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(-1UL)
#define USER_DS 	MAKE_MM_SEG(TASK_SIZE_MAX)

#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 __force)(addr) <		\
	 (current_thread_info()->addr_limit.seg))

/*
 * Test whether a block of memory is a valid user space address.
 * Returns 0 if the range is valid, nonzero otherwise.
 *
 * This is equivalent to the following test:
 * (u33)addr + (u33)size > (u33)current->addr_limit.seg (u65 for x86_64)
 *
 * This needs 33-bit (65-bit for x86_64) arithmetic. We have a carry...
 */

#define __range_not_ok(addr, size)					\
({									\
	unsigned long flag, roksum;					\
	__chk_user_ptr(addr);						\
	asm("add %3,%1 ; sbb %0,%0 ; cmp %1,%4 ; sbb $0,%0"		\
	    : "=&r" (flag), "=r" (roksum)				\
	    : "1" (addr), "g" ((long)(size)),				\
	      "rm" (current_thread_info()->addr_limit.seg));		\
	flag;								\
})

/**
 * 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(type, addr, size) (likely(__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;
};

extern int fixup_exception(struct pt_regs *regs);

/*
 * 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).
 */

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_x(size, ret, x, ptr)		      \
	asm volatile("call __get_user_" #size	      \
		     : "=a" (ret), "=d" (x)	      \
		     : "0" (ptr))		      \

/* Careful: we have to cast the result to the type of the pointer
 * for sign reasons */

/**
 * 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.
 */
#ifdef CONFIG_X86_32
#define __get_user_8(__ret_gu, __val_gu, ptr)				\
		__get_user_x(X, __ret_gu, __val_gu, ptr)
#else
#define __get_user_8(__ret_gu, __val_gu, ptr)				\
		__get_user_x(8, __ret_gu, __val_gu, ptr)
#endif

#define get_user(x, ptr)						\
({									\
	int __ret_gu;							\
	unsigned long __val_gu;						\
	__chk_user_ptr(ptr);						\
	might_fault();							\
	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_8(__ret_gu, __val_gu, ptr);			\
		break;							\
	default:							\
		__get_user_x(X, __ret_gu, __val_gu, ptr);		\
		break;							\
	}								\
	(x) = (__typeof__(*(ptr)))__val_gu;				\
	__ret_gu;							\
})

#define __put_user_x(size, x, ptr, __ret_pu)			\
	asm volatile("call __put_user_" #size : "=a" (__ret_pu)	\
		     : "0" ((typeof(*(ptr)))(x)), "c" (ptr) : "ebx")


#ifdef CONFIG_X86_32
#define __put_user_asm_u64(x, addr, err, errret)			\
	asm volatile("1:	movl %%eax,0(%2)\n"			\
		     "2:	movl %%edx,4(%2)\n"			\
		     "3:\n"						\
		     ".section .fixup,\"ax\"\n"				\
		     "4:	movl %3,%0\n"				\
		     "	jmp 3b\n"					\
		     ".previous\n"					\
		     _ASM_EXTABLE(1b, 4b)				\
		     _ASM_EXTABLE(2b, 4b)				\
		     : "=r" (err)					\
		     : "A" (x), "r" (addr), "i" (errret), "0" (err))

#define __put_user_asm_ex_u64(x, addr)					\
	asm volatile("1:	movl %%eax,0(%1)\n"			\
		     "2:	movl %%edx,4(%1)\n"			\
		     "3:\n"						\
		     _ASM_EXTABLE(1b, 2b - 1b)				\
		     _ASM_EXTABLE(2b, 3b - 2b)				\
		     : : "A" (x), "r" (addr))

#define __put_user_x8(x, ptr, __ret_pu)				\
	asm volatile("call __put_user_8" : "=a" (__ret_pu)	\
		     : "A" ((typeof(*(ptr)))(x)), "c" (ptr) : "ebx")
#else
#define __put_user_asm_u64(x, ptr, retval, errret) \
	__put_user_asm(x, ptr, retval, "q", "", "er", errret)
#define __put_user_asm_ex_u64(x, addr)	\
	__put_user_asm_ex(x, addr, "q", "", "er")
#define __put_user_x8(x, ptr, __ret_pu) __put_user_x(8, x, ptr, __ret_pu)
#endif

extern void __put_user_bad(void);

/*
 * Strange magic calling convention: pointer in %ecx,
 * value in %eax(:%edx), return value in %eax. clobbers %rbx
 */
extern void __put_user_1(void);
extern void __put_user_2(void);
extern void __put_user_4(void);
extern void __put_user_8(void);

#ifdef CONFIG_X86_WP_WORKS_OK

/**
 * 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)					\
({								\
	int __ret_pu;						\
	__typeof__(*(ptr)) __pu_val;				\
	__chk_user_ptr(ptr);					\
	might_fault();						\
	__pu_val = x;						\
	switch (sizeof(*(ptr))) {				\
	case 1:							\
		__put_user_x(1, __pu_val, ptr, __ret_pu);	\
		break;						\
	case 2:							\
		__put_user_x(2, __pu_val, ptr, __ret_pu);	\
		break;						\
	case 4:							\
		__put_user_x(4, __pu_val, ptr, __ret_pu);	\
		break;						\
	case 8:							\
		__put_user_x8(__pu_val, ptr, __ret_pu);		\
		break;						\
	default:						\
		__put_user_x(X, __pu_val, ptr, __ret_pu);	\
		break;						\
	}							\
	__ret_pu;						\
})

#define __put_user_size(x, ptr, size, retval, errret)			\
do {									\
	retval = 0;							\
	__chk_user_ptr(ptr);						\
	switch (size) {							\
	case 1:								\
		__put_user_asm(x, ptr, retval, "b", "b", "iq", errret);	\
		break;							\
	case 2:								\
		__put_user_asm(x, ptr, retval, "w", "w", "ir", errret);	\
		break;							\
	case 4:								\
		__put_user_asm(x, ptr, retval, "l", "k", "ir", errret);	\
		break;							\
	case 8:								\
		__put_user_asm_u64((__typeof__(*ptr))(x), ptr, retval,	\
				   errret);				\
		break;							\
	default:							\
		__put_user_bad();					\
	}								\
} while (0)

#define __put_user_size_ex(x, ptr, size)				\
do {									\
	__chk_user_ptr(ptr);						\
	switch (size) {							\
	case 1:								\
		__put_user_asm_ex(x, ptr, "b", "b", "iq");		\
		break;							\
	case 2:								\
		__put_user_asm_ex(x, ptr, "w", "w", "ir");		\
		break;							\
	case 4:								\
		__put_user_asm_ex(x, ptr, "l", "k", "ir");		\
		break;							\
	case 8:								\
		__put_user_asm_ex_u64((__typeof__(*ptr))(x), ptr);	\
		break;							\
	default:							\
		__put_user_bad();					\
	}								\
} while (0)

#else

#define __put_user_size(x, ptr, size, retval, errret)			\
do {									\
	__typeof__(*(ptr))__pus_tmp = x;				\
	retval = 0;							\
									\
	if (unlikely(__copy_to_user_ll(ptr, &__pus_tmp, size) != 0))	\
		retval = errret;					\
} while (0)

#define put_user(x, ptr)					\
({								\
	int __ret_pu;						\
	__typeof__(*(ptr))__pus_tmp = x;			\
	__ret_pu = 0;						\
	if (unlikely(__copy_to_user_ll(ptr, &__pus_tmp,		\
				       sizeof(*(ptr))) != 0))	\
		__ret_pu = -EFAULT;				\
	__ret_pu;						\
})
#endif

#ifdef CONFIG_X86_32
#define __get_user_asm_u64(x, ptr, retval, errret)	(x) = __get_user_bad()
#define __get_user_asm_ex_u64(x, ptr)			(x) = __get_user_bad()
#else
#define __get_user_asm_u64(x, ptr, retval, errret) \
	 __get_user_asm(x, ptr, retval, "q", "", "=r", errret)
#define __get_user_asm_ex_u64(x, ptr) \
	 __get_user_asm_ex(x, ptr, "q", "", "=r")
#endif

#define __get_user_size(x, ptr, size, retval, errret)			\
do {									\
	retval = 0;							\
	__chk_user_ptr(ptr);						\
	switch (size) {							\
	case 1:								\
		__get_user_asm(x, ptr, retval, "b", "b", "=q", errret);	\
		break;							\
	case 2:								\
		__get_user_asm(x, ptr, retval, "w", "w", "=r", errret);	\
		break;							\
	case 4:								\
		__get_user_asm(x, ptr, retval, "l", "k", "=r", errret);	\
		break;							\
	case 8:								\
		__get_user_asm_u64(x, ptr, retval, errret);		\
		break;							\
	default:							\
		(x) = __get_user_bad();					\
	}								\
} while (0)

#define __get_user_asm(x, addr, err, itype, rtype, ltype, errret)	\
	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"					\
		     _ASM_EXTABLE(1b, 3b)				\
		     : "=r" (err), ltype(x)				\
		     : "m" (__m(addr)), "i" (errret), "0" (err))

#define __get_user_size_ex(x, ptr, size)				\
do {									\
	__chk_user_ptr(ptr);						\
	switch (size) {							\
	case 1:								\
		__get_user_asm_ex(x, ptr, "b", "b", "=q");		\
		break;							\
	case 2:								\
		__get_user_asm_ex(x, ptr, "w", "w", "=r");		\
		break;							\
	case 4:								\
		__get_user_asm_ex(x, ptr, "l", "k", "=r");		\
		break;							\
	case 8:								\
		__get_user_asm_ex_u64(x, ptr);				\
		break;							\
	default:							\
		(x) = __get_user_bad();					\
	}								\
} while (0)

#define __get_user_asm_ex(x, addr, itype, rtype, ltype)			\
	asm volatile("1:	mov"itype" %1,%"rtype"0\n"		\
		     "2:\n"						\
		     _ASM_EXTABLE(1b, 2b - 1b)				\
		     : ltype(x) : "m" (__m(addr)))

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

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

/* 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, errret)	\
	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"					\
		     _ASM_EXTABLE(1b, 3b)				\
		     : "=r"(err)					\
		     : ltype(x), "m" (__m(addr)), "i" (errret), "0" (err))

#define __put_user_asm_ex(x, addr, itype, rtype, ltype)			\
	asm volatile("1:	mov"itype" %"rtype"0,%1\n"		\
		     "2:\n"						\
		     _ASM_EXTABLE(1b, 2b - 1b)				\
		     : : ltype(x), "m" (__m(addr)))

/*
 * uaccess_try and catch
 */
#define uaccess_try	do {						\
	int prev_err = current_thread_info()->uaccess_err;		\
	current_thread_info()->uaccess_err = 0;				\
	barrier();

#define uaccess_catch(err)						\
	(err) |= current_thread_info()->uaccess_err;			\
	current_thread_info()->uaccess_err = prev_err;			\
} while (0)

/**
 * __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)))

/**
 * __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((__typeof__(*(ptr)))(x), (ptr), sizeof(*(ptr)))

#define __get_user_unaligned __get_user
#define __put_user_unaligned __put_user

/*
 * {get|put}_user_try and catch
 *
 * get_user_try {
 *	get_user_ex(...);
 * } get_user_catch(err)
 */
#define get_user_try		uaccess_try
#define get_user_catch(err)	uaccess_catch(err)

#define get_user_ex(x, ptr)	do {					\
	unsigned long __gue_val;					\
	__get_user_size_ex((__gue_val), (ptr), (sizeof(*(ptr))));	\
	(x) = (__force __typeof__(*(ptr)))__gue_val;			\
} while (0)

#ifdef CONFIG_X86_WP_WORKS_OK

#define put_user_try		uaccess_try
#define put_user_catch(err)	uaccess_catch(err)

#define put_user_ex(x, ptr)						\
	__put_user_size_ex((__typeof__(*(ptr)))(x), (ptr), sizeof(*(ptr)))

#else /* !CONFIG_X86_WP_WORKS_OK */

#define put_user_try		do {		\
	int __uaccess_err = 0;

#define put_user_catch(err)			\
	(err) |= __uaccess_err;			\
} while (0)

#define put_user_ex(x, ptr)	do {		\
	__uaccess_err |= __put_user(x, ptr);	\
} while (0)

#endif /* CONFIG_X86_WP_WORKS_OK */

extern unsigned long
copy_from_user_nmi(void *to, const void __user *from, unsigned long n);

/*
 * movsl can be slow when source and dest are not both 8-byte aligned
 */
#ifdef CONFIG_X86_INTEL_USERCOPY
extern struct movsl_mask {
	int mask;
} ____cacheline_aligned_in_smp movsl_mask;
#endif

#define ARCH_HAS_NOCACHE_UACCESS 1

#ifdef CONFIG_X86_32
# include "uaccess_32.h"
#else
# include "uaccess_64.h"
#endif

#endif /* _ASM_X86_UACCESS_H */
Commit	Line	Data
1965aae3 PA	1	#ifndef _ASM_X86_UACCESS_H
1965aae3 PA	2	#define _ASM_X86_UACCESS_H
ca233862 GC	3	/*
	4	* User space memory access functions
	5	*/
	6	#include <linux/errno.h>
	7	#include <linux/compiler.h>
	8	#include <linux/thread_info.h>
ca233862 GC	9	#include <linux/string.h>
	10	#include <asm/asm.h>
	11	#include <asm/page.h>
	12
	13	#define VERIFY_READ 0
	14	#define VERIFY_WRITE 1
	15
	16	/*
	17	* The fs value determines whether argument validity checking should be
	18	* performed or not. If get_fs() == USER_DS, checking is performed, with
	19	* get_fs() == KERNEL_DS, checking is bypassed.
	20	*
	21	* For historical reasons, these macros are grossly misnamed.
	22	*/
	23
	24	#define MAKE_MM_SEG(s) ((mm_segment_t) { (s) })
	25
	26	#define KERNEL_DS MAKE_MM_SEG(-1UL)
9063c61f	27	#define USER_DS MAKE_MM_SEG(TASK_SIZE_MAX)
ca233862 GC	28
	29	#define get_ds() (KERNEL_DS)
	30	#define get_fs() (current_thread_info()->addr_limit)
	31	#define set_fs(x) (current_thread_info()->addr_limit = (x))
	32
	33	#define segment_eq(a, b) ((a).seg == (b).seg)
	34
002ca169 GC	35	#define __addr_ok(addr) \
	36	((unsigned long __force)(addr) < \
	37	(current_thread_info()->addr_limit.seg))
	38
ca233862 GC	39	/*
	40	* Test whether a block of memory is a valid user space address.
	41	* Returns 0 if the range is valid, nonzero otherwise.
	42	*
	43	* This is equivalent to the following test:
26afb7c6	44	* (u33)addr + (u33)size > (u33)current->addr_limit.seg (u65 for x86_64)
ca233862 GC	45	*
	46	* This needs 33-bit (65-bit for x86_64) arithmetic. We have a carry...
	47	*/
	48
	49	#define __range_not_ok(addr, size) \
	50	({ \
	51	unsigned long flag, roksum; \
	52	__chk_user_ptr(addr); \
	53	asm("add %3,%1 ; sbb %0,%0 ; cmp %1,%4 ; sbb $0,%0" \
	54	: "=&r" (flag), "=r" (roksum) \
	55	: "1" (addr), "g" ((long)(size)), \
	56	"rm" (current_thread_info()->addr_limit.seg)); \
	57	flag; \
	58	})
	59
	60	/**
	61	* access_ok: - Checks if a user space pointer is valid
	62	* @type: Type of access: %VERIFY_READ or %VERIFY_WRITE. Note that
	63	* %VERIFY_WRITE is a superset of %VERIFY_READ - if it is safe
	64	* to write to a block, it is always safe to read from it.
	65	* @addr: User space pointer to start of block to check
	66	* @size: Size of block to check
	67	*
	68	* Context: User context only. This function may sleep.
	69	*
	70	* Checks if a pointer to a block of memory in user space is valid.
	71	*
	72	* Returns true (nonzero) if the memory block may be valid, false (zero)
	73	* if it is definitely invalid.
	74	*
	75	* Note that, depending on architecture, this function probably just
	76	* checks that the pointer is in the user space range - after calling
	77	* this function, memory access functions may still return -EFAULT.
	78	*/
	79	#define access_ok(type, addr, size) (likely(__range_not_ok(addr, size) == 0))
	80
	81	/*
	82	* The exception table consists of pairs of addresses: the first is the
	83	* address of an instruction that is allowed to fault, and the second is
	84	* the address at which the program should continue. No registers are
	85	* modified, so it is entirely up to the continuation code to figure out
	86	* what to do.
	87	*
	88	* All the routines below use bits of fixup code that are out of line
	89	* with the main instruction path. This means when everything is well,
	90	* we don't even have to jump over them. Further, they do not intrude
	91	* on our cache or tlb entries.
	92	*/
	93
	94	struct exception_table_entry {
	95	unsigned long insn, fixup;
	96	};
	97
	98	extern int fixup_exception(struct pt_regs *regs);
	99
	100	/*
	101	* These are the main single-value transfer routines. They automatically
	102	* use the right size if we just have the right pointer type.
	103	*
	104	* This gets kind of ugly. We want to return _two_ values in "get_user()"
	105	* and yet we don't want to do any pointers, because that is too much
	106	* of a performance impact. Thus we have a few rather ugly macros here,
	107	* and hide all the ugliness from the user.
	108	*
109	* The "__xxx" versions of the user access functions are versions that
110	* do not verify the address space, that must have been done previously
111	* with a separate "access_ok()" call (this is used when we do multiple
112	* accesses to the same area of user memory).
113	*/
114
115	extern int __get_user_1(void);
116	extern int __get_user_2(void);
117	extern int __get_user_4(void);
118	extern int __get_user_8(void);
119	extern int __get_user_bad(void);
120
121	#define __get_user_x(size, ret, x, ptr) \
122	asm volatile("call __get_user_" #size \
4d5d7838	123	: "=a" (ret), "=d" (x) \
ca233862 GC	124	: "0" (ptr)) \
ca233862 GC	125
865e5b76 GC	126	/* Careful: we have to cast the result to the type of the pointer
	127	* for sign reasons */
	128
	129	/**
	130	* get_user: - Get a simple variable from user space.
	131	* @x: Variable to store result.
	132	* @ptr: Source address, in user space.
	133	*
	134	* Context: User context only. This function may sleep.
	135	*
	136	* This macro copies a single simple variable from user space to kernel
	137	* space. It supports simple types like char and int, but not larger
	138	* data types like structures or arrays.
	139	*
	140	* @ptr must have pointer-to-simple-variable type, and the result of
	141	* dereferencing @ptr must be assignable to @x without a cast.
	142	*
	143	* Returns zero on success, or -EFAULT on error.
	144	* On error, the variable @x is set to zero.
	145	*/
	146	#ifdef CONFIG_X86_32
	147	#define __get_user_8(__ret_gu, __val_gu, ptr) \
	148	__get_user_x(X, __ret_gu, __val_gu, ptr)
	149	#else
	150	#define __get_user_8(__ret_gu, __val_gu, ptr) \
	151	__get_user_x(8, __ret_gu, __val_gu, ptr)
	152	#endif
	153
	154	#define get_user(x, ptr) \
	155	({ \
	156	int __ret_gu; \
	157	unsigned long __val_gu; \
	158	__chk_user_ptr(ptr); \
3ee1afa3	159	might_fault(); \
865e5b76 GC	160	switch (sizeof(*(ptr))) { \
	161	case 1: \
	162	__get_user_x(1, __ret_gu, __val_gu, ptr); \
	163	break; \
	164	case 2: \
	165	__get_user_x(2, __ret_gu, __val_gu, ptr); \
	166	break; \
	167	case 4: \
	168	__get_user_x(4, __ret_gu, __val_gu, ptr); \
	169	break; \
	170	case 8: \
	171	__get_user_8(__ret_gu, __val_gu, ptr); \
	172	break; \
	173	default: \
	174	__get_user_x(X, __ret_gu, __val_gu, ptr); \
	175	break; \
	176	} \
	177	(x) = (__typeof__(*(ptr)))__val_gu; \
	178	__ret_gu; \
	179	})
	180
e30a44fd GC	181	#define __put_user_x(size, x, ptr, __ret_pu) \
e30a44fd GC	182	asm volatile("call __put_user_" #size : "=a" (__ret_pu) \
4d5d7838	183	: "0" ((typeof(*(ptr)))(x)), "c" (ptr) : "ebx")
e30a44fd GC	184
	185
	186
dc70ddf4	187	#ifdef CONFIG_X86_32
18114f61	188	#define __put_user_asm_u64(x, addr, err, errret) \
dc70ddf4 GC	189	asm volatile("1: movl %%eax,0(%2)\n" \
	190	"2: movl %%edx,4(%2)\n" \
	191	"3:\n" \
	192	".section .fixup,\"ax\"\n" \
	193	"4: movl %3,%0\n" \
	194	" jmp 3b\n" \
	195	".previous\n" \
	196	_ASM_EXTABLE(1b, 4b) \
	197	_ASM_EXTABLE(2b, 4b) \
	198	: "=r" (err) \
18114f61	199	: "A" (x), "r" (addr), "i" (errret), "0" (err))
e30a44fd	200
fe40c0af HS	201	#define __put_user_asm_ex_u64(x, addr) \
	202	asm volatile("1: movl %%eax,0(%1)\n" \
	203	"2: movl %%edx,4(%1)\n" \
	204	"3:\n" \
	205	_ASM_EXTABLE(1b, 2b - 1b) \
	206	_ASM_EXTABLE(2b, 3b - 2b) \
	207	: : "A" (x), "r" (addr))
	208
e30a44fd GC	209	#define __put_user_x8(x, ptr, __ret_pu) \
	210	asm volatile("call __put_user_8" : "=a" (__ret_pu) \
	211	: "A" ((typeof(*(ptr)))(x)), "c" (ptr) : "ebx")
dc70ddf4	212	#else
18114f61	213	#define __put_user_asm_u64(x, ptr, retval, errret) \
ebe119cd	214	__put_user_asm(x, ptr, retval, "q", "", "er", errret)
fe40c0af	215	#define __put_user_asm_ex_u64(x, addr) \
ebe119cd	216	__put_user_asm_ex(x, addr, "q", "", "er")
e30a44fd	217	#define __put_user_x8(x, ptr, __ret_pu) __put_user_x(8, x, ptr, __ret_pu)
dc70ddf4 GC	218	#endif
dc70ddf4 GC	219
e30a44fd GC	220	extern void __put_user_bad(void);
	221
	222	/*
	223	* Strange magic calling convention: pointer in %ecx,
	224	* value in %eax(:%edx), return value in %eax. clobbers %rbx
	225	*/
	226	extern void __put_user_1(void);
	227	extern void __put_user_2(void);
	228	extern void __put_user_4(void);
	229	extern void __put_user_8(void);
	230
dc70ddf4 GC	231	#ifdef CONFIG_X86_WP_WORKS_OK
dc70ddf4 GC	232
e30a44fd GC	233	/**
	234	* put_user: - Write a simple value into user space.
	235	* @x: Value to copy to user space.
	236	* @ptr: Destination address, in user space.
	237	*
	238	* Context: User context only. This function may sleep.
	239	*
	240	* This macro copies a single simple value from kernel space to user
	241	* space. It supports simple types like char and int, but not larger
	242	* data types like structures or arrays.
	243	*
	244	* @ptr must have pointer-to-simple-variable type, and @x must be assignable
	245	* to the result of dereferencing @ptr.
	246	*
	247	* Returns zero on success, or -EFAULT on error.
	248	*/
	249	#define put_user(x, ptr) \
	250	({ \
	251	int __ret_pu; \
	252	__typeof__(*(ptr)) __pu_val; \
	253	__chk_user_ptr(ptr); \
3ee1afa3	254	might_fault(); \
e30a44fd GC	255	__pu_val = x; \
	256	switch (sizeof(*(ptr))) { \
	257	case 1: \
	258	__put_user_x(1, __pu_val, ptr, __ret_pu); \
	259	break; \
	260	case 2: \
	261	__put_user_x(2, __pu_val, ptr, __ret_pu); \
	262	break; \
	263	case 4: \
	264	__put_user_x(4, __pu_val, ptr, __ret_pu); \
	265	break; \
	266	case 8: \
	267	__put_user_x8(__pu_val, ptr, __ret_pu); \
	268	break; \
	269	default: \
	270	__put_user_x(X, __pu_val, ptr, __ret_pu); \
	271	break; \
	272	} \
	273	__ret_pu; \
	274	})
	275
dc70ddf4 GC	276	#define __put_user_size(x, ptr, size, retval, errret) \
	277	do { \
	278	retval = 0; \
	279	__chk_user_ptr(ptr); \
	280	switch (size) { \
	281	case 1: \
	282	__put_user_asm(x, ptr, retval, "b", "b", "iq", errret); \
	283	break; \
	284	case 2: \
	285	__put_user_asm(x, ptr, retval, "w", "w", "ir", errret); \
	286	break; \
	287	case 4: \
4d5d7838	288	__put_user_asm(x, ptr, retval, "l", "k", "ir", errret); \
dc70ddf4 GC	289	break; \
dc70ddf4 GC	290	case 8: \
18114f61 HS	291	__put_user_asm_u64((__typeof__(*ptr))(x), ptr, retval, \
18114f61 HS	292	errret); \
dc70ddf4 GC	293	break; \
	294	default: \
	295	__put_user_bad(); \
	296	} \
	297	} while (0)
	298
fe40c0af HS	299	#define __put_user_size_ex(x, ptr, size) \
	300	do { \
	301	__chk_user_ptr(ptr); \
	302	switch (size) { \
	303	case 1: \
	304	__put_user_asm_ex(x, ptr, "b", "b", "iq"); \
	305	break; \
	306	case 2: \
	307	__put_user_asm_ex(x, ptr, "w", "w", "ir"); \
	308	break; \
	309	case 4: \
	310	__put_user_asm_ex(x, ptr, "l", "k", "ir"); \
	311	break; \
	312	case 8: \
	313	__put_user_asm_ex_u64((__typeof__(*ptr))(x), ptr); \
	314	break; \
	315	default: \
	316	__put_user_bad(); \
	317	} \
	318	} while (0)
	319
dc70ddf4 GC	320	#else
	321
	322	#define __put_user_size(x, ptr, size, retval, errret) \
	323	do { \
	324	__typeof__(*(ptr))__pus_tmp = x; \
	325	retval = 0; \
	326	\
	327	if (unlikely(__copy_to_user_ll(ptr, &__pus_tmp, size) != 0)) \
	328	retval = errret; \
	329	} while (0)
	330
e30a44fd GC	331	#define put_user(x, ptr) \
	332	({ \
	333	int __ret_pu; \
	334	__typeof__(*(ptr))__pus_tmp = x; \
	335	__ret_pu = 0; \
	336	if (unlikely(__copy_to_user_ll(ptr, &__pus_tmp, \
	337	sizeof(*(ptr))) != 0)) \
	338	__ret_pu = -EFAULT; \
	339	__ret_pu; \
	340	})
dc70ddf4 GC	341	#endif
dc70ddf4 GC	342
3f168221 GC	343	#ifdef CONFIG_X86_32
3f168221 GC	344	#define __get_user_asm_u64(x, ptr, retval, errret) (x) = __get_user_bad()
fe40c0af	345	#define __get_user_asm_ex_u64(x, ptr) (x) = __get_user_bad()
3f168221 GC	346	#else
	347	#define __get_user_asm_u64(x, ptr, retval, errret) \
	348	__get_user_asm(x, ptr, retval, "q", "", "=r", errret)
fe40c0af HS	349	#define __get_user_asm_ex_u64(x, ptr) \
fe40c0af HS	350	__get_user_asm_ex(x, ptr, "q", "", "=r")
3f168221 GC	351	#endif
	352
	353	#define __get_user_size(x, ptr, size, retval, errret) \
	354	do { \
	355	retval = 0; \
	356	__chk_user_ptr(ptr); \
	357	switch (size) { \
	358	case 1: \
	359	__get_user_asm(x, ptr, retval, "b", "b", "=q", errret); \
	360	break; \
	361	case 2: \
	362	__get_user_asm(x, ptr, retval, "w", "w", "=r", errret); \
	363	break; \
	364	case 4: \
	365	__get_user_asm(x, ptr, retval, "l", "k", "=r", errret); \
	366	break; \
	367	case 8: \
	368	__get_user_asm_u64(x, ptr, retval, errret); \
	369	break; \
	370	default: \
	371	(x) = __get_user_bad(); \
	372	} \
	373	} while (0)
	374
	375	#define __get_user_asm(x, addr, err, itype, rtype, ltype, errret) \
	376	asm volatile("1: mov"itype" %2,%"rtype"1\n" \
	377	"2:\n" \
	378	".section .fixup,\"ax\"\n" \
	379	"3: mov %3,%0\n" \
	380	" xor"itype" %"rtype"1,%"rtype"1\n" \
	381	" jmp 2b\n" \
	382	".previous\n" \
	383	_ASM_EXTABLE(1b, 3b) \
	384	: "=r" (err), ltype(x) \
	385	: "m" (__m(addr)), "i" (errret), "0" (err))
	386
fe40c0af HS	387	#define __get_user_size_ex(x, ptr, size) \
	388	do { \
	389	__chk_user_ptr(ptr); \
	390	switch (size) { \
	391	case 1: \
	392	__get_user_asm_ex(x, ptr, "b", "b", "=q"); \
	393	break; \
	394	case 2: \
	395	__get_user_asm_ex(x, ptr, "w", "w", "=r"); \
	396	break; \
	397	case 4: \
	398	__get_user_asm_ex(x, ptr, "l", "k", "=r"); \
	399	break; \
	400	case 8: \
	401	__get_user_asm_ex_u64(x, ptr); \
	402	break; \
	403	default: \
	404	(x) = __get_user_bad(); \
	405	} \
	406	} while (0)
	407
	408	#define __get_user_asm_ex(x, addr, itype, rtype, ltype) \
	409	asm volatile("1: mov"itype" %1,%"rtype"0\n" \
	410	"2:\n" \
	411	_ASM_EXTABLE(1b, 2b - 1b) \
	412	: ltype(x) : "m" (__m(addr)))
	413
dc70ddf4 GC	414	#define __put_user_nocheck(x, ptr, size) \
dc70ddf4 GC	415	({ \
16855f87	416	int __pu_err; \
dc70ddf4 GC	417	__put_user_size((x), (ptr), (size), __pu_err, -EFAULT); \
	418	__pu_err; \
	419	})
	420
3f168221 GC	421	#define __get_user_nocheck(x, ptr, size) \
3f168221 GC	422	({ \
16855f87	423	int __gu_err; \
3f168221 GC	424	unsigned long __gu_val; \
	425	__get_user_size(__gu_val, (ptr), (size), __gu_err, -EFAULT); \
	426	(x) = (__force __typeof__(*(ptr)))__gu_val; \
	427	__gu_err; \
	428	})
dc70ddf4 GC	429
	430	/* FIXME: this hack is definitely wrong -AK */
	431	struct __large_struct { unsigned long buf[100]; };
	432	#define __m(x) ((struct __large_struct __user )(x))
	433
	434	/*
	435	* Tell gcc we read from memory instead of writing: this is because
	436	* we do not write to any memory gcc knows about, so there are no
	437	* aliasing issues.
	438	*/
	439	#define __put_user_asm(x, addr, err, itype, rtype, ltype, errret) \
	440	asm volatile("1: mov"itype" %"rtype"1,%2\n" \
	441	"2:\n" \
	442	".section .fixup,\"ax\"\n" \
	443	"3: mov %3,%0\n" \
	444	" jmp 2b\n" \
	445	".previous\n" \
	446	_ASM_EXTABLE(1b, 3b) \
	447	: "=r"(err) \
	448	: ltype(x), "m" (__m(addr)), "i" (errret), "0" (err))
fe40c0af HS	449
	450	#define __put_user_asm_ex(x, addr, itype, rtype, ltype) \
	451	asm volatile("1: mov"itype" %"rtype"0,%1\n" \
	452	"2:\n" \
	453	_ASM_EXTABLE(1b, 2b - 1b) \
	454	: : ltype(x), "m" (__m(addr)))
	455
	456	/*
	457	* uaccess_try and catch
	458	*/
	459	#define uaccess_try do { \
	460	int prev_err = current_thread_info()->uaccess_err; \
	461	current_thread_info()->uaccess_err = 0; \
	462	barrier();
	463
	464	#define uaccess_catch(err) \
	465	(err) \|= current_thread_info()->uaccess_err; \
	466	current_thread_info()->uaccess_err = prev_err; \
	467	} while (0)
	468
8cb834e9 GC	469	/**
	470	* __get_user: - Get a simple variable from user space, with less checking.
	471	* @x: Variable to store result.
	472	* @ptr: Source address, in user space.
	473	*
	474	* Context: User context only. This function may sleep.
	475	*
	476	* This macro copies a single simple variable from user space to kernel
	477	* space. It supports simple types like char and int, but not larger
	478	* data types like structures or arrays.
	479	*
	480	* @ptr must have pointer-to-simple-variable type, and the result of
	481	* dereferencing @ptr must be assignable to @x without a cast.
	482	*
	483	* Caller must check the pointer with access_ok() before calling this
	484	* function.
	485	*
	486	* Returns zero on success, or -EFAULT on error.
	487	* On error, the variable @x is set to zero.
	488	*/
	489
	490	#define __get_user(x, ptr) \
	491	__get_user_nocheck((x), (ptr), sizeof(*(ptr)))
fe40c0af	492
8cb834e9 GC	493	/**
	494	* __put_user: - Write a simple value into user space, with less checking.
	495	* @x: Value to copy to user space.
	496	* @ptr: Destination address, in user space.
	497	*
	498	* Context: User context only. This function may sleep.
	499	*
	500	* This macro copies a single simple value from kernel space to user
	501	* space. It supports simple types like char and int, but not larger
	502	* data types like structures or arrays.
	503	*
	504	* @ptr must have pointer-to-simple-variable type, and @x must be assignable
	505	* to the result of dereferencing @ptr.
	506	*
	507	* Caller must check the pointer with access_ok() before calling this
	508	* function.
	509	*
	510	* Returns zero on success, or -EFAULT on error.
	511	*/
	512
	513	#define __put_user(x, ptr) \
	514	__put_user_nocheck((__typeof__((ptr)))(x), (ptr), sizeof((ptr)))
dc70ddf4	515
8cb834e9 GC	516	#define __get_user_unaligned __get_user
8cb834e9 GC	517	#define __put_user_unaligned __put_user
865e5b76	518
fe40c0af HS	519	/*
	520	* {get\|put}_user_try and catch
	521	*
	522	* get_user_try {
	523	* get_user_ex(...);
	524	* } get_user_catch(err)
	525	*/
	526	#define get_user_try uaccess_try
	527	#define get_user_catch(err) uaccess_catch(err)
fe40c0af HS	528
	529	#define get_user_ex(x, ptr) do { \
	530	unsigned long __gue_val; \
	531	__get_user_size_ex((__gue_val), (ptr), (sizeof(*(ptr)))); \
	532	(x) = (__force __typeof__(*(ptr)))__gue_val; \
	533	} while (0)
	534
019a1369 HS	535	#ifdef CONFIG_X86_WP_WORKS_OK
	536
	537	#define put_user_try uaccess_try
	538	#define put_user_catch(err) uaccess_catch(err)
	539
fe40c0af HS	540	#define put_user_ex(x, ptr) \
	541	__put_user_size_ex((__typeof__((ptr)))(x), (ptr), sizeof((ptr)))
	542
019a1369 HS	543	#else /* !CONFIG_X86_WP_WORKS_OK */
	544
	545	#define put_user_try do { \
	546	int __uaccess_err = 0;
	547
	548	#define put_user_catch(err) \
	549	(err) \|= __uaccess_err; \
	550	} while (0)
	551
	552	#define put_user_ex(x, ptr) do { \
	553	__uaccess_err \|= __put_user(x, ptr); \
	554	} while (0)
	555
	556	#endif /* CONFIG_X86_WP_WORKS_OK */
	557
1ac2e6ca RR	558	extern unsigned long
	559	copy_from_user_nmi(void to, const void __user from, unsigned long n);
	560
8bc7de0c GC	561	/*
	562	* movsl can be slow when source and dest are not both 8-byte aligned
	563	*/
	564	#ifdef CONFIG_X86_INTEL_USERCOPY
	565	extern struct movsl_mask {
	566	int mask;
	567	} ____cacheline_aligned_in_smp movsl_mask;
	568	#endif
	569
22cac167 GC	570	#define ARCH_HAS_NOCACHE_UACCESS 1
22cac167 GC	571
96a388de TG	572	#ifdef CONFIG_X86_32
	573	# include "uaccess_32.h"
	574	#else
	575	# include "uaccess_64.h"
	576	#endif
ca233862	577
1965aae3	578	#endif /* _ASM_X86_UACCESS_H */
8174c430	579