325 lines
		
	
	
		
			9.5 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			325 lines
		
	
	
		
			9.5 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * Copyright (C) 2004-2006 Atmel Corporation
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|  *
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|  * This program is free software; you can redistribute it and/or modify
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|  * it under the terms of the GNU General Public License version 2 as
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|  * published by the Free Software Foundation.
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|  */
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| #ifndef __ASM_AVR32_UACCESS_H
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| #define __ASM_AVR32_UACCESS_H
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| 
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| #include <linux/errno.h>
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| #include <linux/sched.h>
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| 
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| #define VERIFY_READ	0
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| #define VERIFY_WRITE	1
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| 
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| typedef struct {
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| 	unsigned int is_user_space;
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| } mm_segment_t;
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| 
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| /*
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|  * The fs value determines whether argument validity checking should be
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|  * performed or not.  If get_fs() == USER_DS, checking is performed, with
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|  * get_fs() == KERNEL_DS, checking is bypassed.
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|  *
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|  * For historical reasons (Data Segment Register?), these macros are misnamed.
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|  */
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| #define MAKE_MM_SEG(s)	((mm_segment_t) { (s) })
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| #define segment_eq(a,b)	((a).is_user_space == (b).is_user_space)
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| 
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| #define USER_ADDR_LIMIT 0x80000000
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| 
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| #define KERNEL_DS	MAKE_MM_SEG(0)
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| #define USER_DS		MAKE_MM_SEG(1)
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| 
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| #define get_ds()	(KERNEL_DS)
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| 
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| static inline mm_segment_t get_fs(void)
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| {
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| 	return MAKE_MM_SEG(test_thread_flag(TIF_USERSPACE));
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| }
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| 
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| static inline void set_fs(mm_segment_t s)
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| {
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| 	if (s.is_user_space)
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| 		set_thread_flag(TIF_USERSPACE);
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| 	else
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| 		clear_thread_flag(TIF_USERSPACE);
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| }
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| 
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| /*
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|  * Test whether a block of memory is a valid user space address.
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|  * Returns 0 if the range is valid, nonzero otherwise.
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|  *
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|  * We do the following checks:
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|  *   1. Is the access from kernel space?
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|  *   2. Does (addr + size) set the carry bit?
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|  *   3. Is (addr + size) a negative number (i.e. >= 0x80000000)?
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|  *
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|  * If yes on the first check, access is granted.
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|  * If no on any of the others, access is denied.
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|  */
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| #define __range_ok(addr, size)						\
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| 	(test_thread_flag(TIF_USERSPACE)				\
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| 	 && (((unsigned long)(addr) >= 0x80000000)			\
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| 	     || ((unsigned long)(size) > 0x80000000)			\
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| 	     || (((unsigned long)(addr) + (unsigned long)(size)) > 0x80000000)))
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| 
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| #define access_ok(type, addr, size) (likely(__range_ok(addr, size) == 0))
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| 
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| /* Generic arbitrary sized copy. Return the number of bytes NOT copied */
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| extern __kernel_size_t __copy_user(void *to, const void *from,
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| 				   __kernel_size_t n);
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| 
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| extern __kernel_size_t copy_to_user(void __user *to, const void *from,
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| 				    __kernel_size_t n);
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| extern __kernel_size_t copy_from_user(void *to, const void __user *from,
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| 				      __kernel_size_t n);
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| 
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| static inline __kernel_size_t __copy_to_user(void __user *to, const void *from,
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| 					     __kernel_size_t n)
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| {
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| 	return __copy_user((void __force *)to, from, n);
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| }
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| static inline __kernel_size_t __copy_from_user(void *to,
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| 					       const void __user *from,
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| 					       __kernel_size_t n)
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| {
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| 	return __copy_user(to, (const void __force *)from, n);
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| }
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| 
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| #define __copy_to_user_inatomic __copy_to_user
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| #define __copy_from_user_inatomic __copy_from_user
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| 
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| /*
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|  * put_user: - Write a simple value into user space.
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|  * @x:   Value to copy to user space.
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|  * @ptr: Destination address, in user space.
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|  *
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|  * Context: User context only.  This function may sleep.
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|  *
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|  * This macro copies a single simple value from kernel space to user
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|  * space.  It supports simple types like char and int, but not larger
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|  * data types like structures or arrays.
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|  *
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|  * @ptr must have pointer-to-simple-variable type, and @x must be assignable
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|  * to the result of dereferencing @ptr.
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|  *
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|  * Returns zero on success, or -EFAULT on error.
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|  */
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| #define put_user(x,ptr)	\
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| 	__put_user_check((x),(ptr),sizeof(*(ptr)))
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| 
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| /*
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|  * get_user: - Get a simple variable from user space.
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|  * @x:   Variable to store result.
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|  * @ptr: Source address, in user space.
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|  *
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|  * Context: User context only.  This function may sleep.
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|  *
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|  * This macro copies a single simple variable from user space to kernel
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|  * space.  It supports simple types like char and int, but not larger
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|  * data types like structures or arrays.
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|  *
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|  * @ptr must have pointer-to-simple-variable type, and the result of
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|  * dereferencing @ptr must be assignable to @x without a cast.
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|  *
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|  * Returns zero on success, or -EFAULT on error.
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|  * On error, the variable @x is set to zero.
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|  */
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| #define get_user(x,ptr) \
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| 	__get_user_check((x),(ptr),sizeof(*(ptr)))
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| 
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| /*
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|  * __put_user: - Write a simple value into user space, with less checking.
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|  * @x:   Value to copy to user space.
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|  * @ptr: Destination address, in user space.
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|  *
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|  * Context: User context only.  This function may sleep.
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|  *
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|  * This macro copies a single simple value from kernel space to user
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|  * space.  It supports simple types like char and int, but not larger
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|  * data types like structures or arrays.
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|  *
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|  * @ptr must have pointer-to-simple-variable type, and @x must be assignable
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|  * to the result of dereferencing @ptr.
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|  *
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|  * Caller must check the pointer with access_ok() before calling this
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|  * function.
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|  *
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|  * Returns zero on success, or -EFAULT on error.
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|  */
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| #define __put_user(x,ptr) \
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| 	__put_user_nocheck((x),(ptr),sizeof(*(ptr)))
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| 
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| /*
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|  * __get_user: - Get a simple variable from user space, with less checking.
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|  * @x:   Variable to store result.
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|  * @ptr: Source address, in user space.
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|  *
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|  * Context: User context only.  This function may sleep.
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|  *
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|  * This macro copies a single simple variable from user space to kernel
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|  * space.  It supports simple types like char and int, but not larger
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|  * data types like structures or arrays.
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|  *
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|  * @ptr must have pointer-to-simple-variable type, and the result of
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|  * dereferencing @ptr must be assignable to @x without a cast.
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|  *
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|  * Caller must check the pointer with access_ok() before calling this
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|  * function.
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|  *
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|  * Returns zero on success, or -EFAULT on error.
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|  * On error, the variable @x is set to zero.
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|  */
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| #define __get_user(x,ptr) \
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| 	__get_user_nocheck((x),(ptr),sizeof(*(ptr)))
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| 
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| extern int __get_user_bad(void);
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| extern int __put_user_bad(void);
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| 
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| #define __get_user_nocheck(x, ptr, size)				\
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| ({									\
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| 	unsigned long __gu_val = 0;					\
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| 	int __gu_err = 0;						\
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| 									\
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| 	switch (size) {							\
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| 	case 1: __get_user_asm("ub", __gu_val, ptr, __gu_err); break;	\
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| 	case 2: __get_user_asm("uh", __gu_val, ptr, __gu_err); break;	\
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| 	case 4: __get_user_asm("w", __gu_val, ptr, __gu_err); break;	\
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| 	default: __gu_err = __get_user_bad(); break;			\
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| 	}								\
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| 									\
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| 	x = (typeof(*(ptr)))__gu_val;					\
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| 	__gu_err;							\
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| })
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| 
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| #define __get_user_check(x, ptr, size)					\
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| ({									\
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| 	unsigned long __gu_val = 0;					\
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| 	const typeof(*(ptr)) __user * __gu_addr = (ptr);		\
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| 	int __gu_err = 0;						\
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| 									\
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| 	if (access_ok(VERIFY_READ, __gu_addr, size)) {			\
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| 		switch (size) {						\
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| 		case 1:							\
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| 			__get_user_asm("ub", __gu_val, __gu_addr,	\
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| 				       __gu_err);			\
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| 			break;						\
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| 		case 2:							\
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| 			__get_user_asm("uh", __gu_val, __gu_addr,	\
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| 				       __gu_err);			\
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| 			break;						\
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| 		case 4:							\
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| 			__get_user_asm("w", __gu_val, __gu_addr,	\
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| 				       __gu_err);			\
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| 			break;						\
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| 		default:						\
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| 			__gu_err = __get_user_bad();			\
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| 			break;						\
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| 		}							\
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| 	} else {							\
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| 		__gu_err = -EFAULT;					\
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| 	}								\
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| 	x = (typeof(*(ptr)))__gu_val;					\
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| 	__gu_err;							\
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| })
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| 
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| #define __get_user_asm(suffix, __gu_val, ptr, __gu_err)			\
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| 	asm volatile(							\
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| 		"1:	ld." suffix "	%1, %3			\n"	\
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| 		"2:						\n"	\
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| 		"	.subsection 1				\n"	\
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| 		"3:	mov	%0, %4				\n"	\
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| 		"	rjmp	2b				\n"	\
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| 		"	.subsection 0				\n"	\
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| 		"	.section __ex_table, \"a\"		\n"	\
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| 		"	.long	1b, 3b				\n"	\
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| 		"	.previous				\n"	\
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| 		: "=r"(__gu_err), "=r"(__gu_val)			\
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| 		: "0"(__gu_err), "m"(*(ptr)), "i"(-EFAULT))
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| 
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| #define __put_user_nocheck(x, ptr, size)				\
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| ({									\
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| 	typeof(*(ptr)) __pu_val;					\
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| 	int __pu_err = 0;						\
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| 									\
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| 	__pu_val = (x);							\
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| 	switch (size) {							\
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| 	case 1: __put_user_asm("b", ptr, __pu_val, __pu_err); break;	\
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| 	case 2: __put_user_asm("h", ptr, __pu_val, __pu_err); break;	\
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| 	case 4: __put_user_asm("w", ptr, __pu_val, __pu_err); break;	\
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| 	case 8: __put_user_asm("d", ptr, __pu_val, __pu_err); break;	\
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| 	default: __pu_err = __put_user_bad(); break;			\
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| 	}								\
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| 	__pu_err;							\
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| })
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| 
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| #define __put_user_check(x, ptr, size)					\
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| ({									\
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| 	typeof(*(ptr)) __pu_val;					\
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| 	typeof(*(ptr)) __user *__pu_addr = (ptr);			\
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| 	int __pu_err = 0;						\
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| 									\
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| 	__pu_val = (x);							\
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| 	if (access_ok(VERIFY_WRITE, __pu_addr, size)) {			\
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| 		switch (size) {						\
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| 		case 1:							\
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| 			__put_user_asm("b", __pu_addr, __pu_val,	\
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| 				       __pu_err);			\
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| 			break;						\
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| 		case 2:							\
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| 			__put_user_asm("h", __pu_addr, __pu_val,	\
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| 				       __pu_err);			\
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| 			break;						\
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| 		case 4:							\
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| 			__put_user_asm("w", __pu_addr, __pu_val,	\
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| 				       __pu_err);			\
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| 			break;						\
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| 		case 8:							\
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| 			__put_user_asm("d", __pu_addr, __pu_val,		\
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| 				       __pu_err);			\
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| 			break;						\
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| 		default:						\
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| 			__pu_err = __put_user_bad();			\
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| 			break;						\
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| 		}							\
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| 	} else {							\
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| 		__pu_err = -EFAULT;					\
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| 	}								\
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| 	__pu_err;							\
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| })
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| 
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| #define __put_user_asm(suffix, ptr, __pu_val, __gu_err)			\
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| 	asm volatile(							\
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| 		"1:	st." suffix "	%1, %3			\n"	\
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| 		"2:						\n"	\
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| 		"	.subsection 1				\n"	\
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| 		"3:	mov	%0, %4				\n"	\
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| 		"	rjmp	2b				\n"	\
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| 		"	.subsection 0				\n"	\
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| 		"	.section __ex_table, \"a\"		\n"	\
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| 		"	.long	1b, 3b				\n"	\
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| 		"	.previous				\n"	\
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| 		: "=r"(__gu_err), "=m"(*(ptr))				\
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| 		: "0"(__gu_err), "r"(__pu_val), "i"(-EFAULT))
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| 
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| extern __kernel_size_t clear_user(void __user *addr, __kernel_size_t size);
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| extern __kernel_size_t __clear_user(void __user *addr, __kernel_size_t size);
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| 
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| extern long strncpy_from_user(char *dst, const char __user *src, long count);
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| extern long __strncpy_from_user(char *dst, const char __user *src, long count);
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| 
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| extern long strnlen_user(const char __user *__s, long __n);
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| extern long __strnlen_user(const char __user *__s, long __n);
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| 
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| #define strlen_user(s) strnlen_user(s, ~0UL >> 1)
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| 
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| struct exception_table_entry
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| {
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| 	unsigned long insn, fixup;
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| };
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| 
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| #endif /* __ASM_AVR32_UACCESS_H */
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