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- /*
- * Copyright (C) 2004-2006 Atmel Corporation
- *
- * 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 __ASM_AVR32_UACCESS_H
- #define __ASM_AVR32_UACCESS_H
- #include <linux/errno.h>
- #include <linux/sched.h>
- #define VERIFY_READ 0
- #define VERIFY_WRITE 1
- typedef struct {
- unsigned int is_user_space;
- } mm_segment_t;
- /*
- * 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 (Data Segment Register?), these macros are misnamed.
- */
- #define MAKE_MM_SEG(s) ((mm_segment_t) { (s) })
- #define segment_eq(a,b) ((a).is_user_space == (b).is_user_space)
- #define USER_ADDR_LIMIT 0x80000000
- #define KERNEL_DS MAKE_MM_SEG(0)
- #define USER_DS MAKE_MM_SEG(1)
- #define get_ds() (KERNEL_DS)
- static inline mm_segment_t get_fs(void)
- {
- return MAKE_MM_SEG(test_thread_flag(TIF_USERSPACE));
- }
- static inline void set_fs(mm_segment_t s)
- {
- if (s.is_user_space)
- set_thread_flag(TIF_USERSPACE);
- else
- clear_thread_flag(TIF_USERSPACE);
- }
- /*
- * Test whether a block of memory is a valid user space address.
- * Returns 0 if the range is valid, nonzero otherwise.
- *
- * We do the following checks:
- * 1. Is the access from kernel space?
- * 2. Does (addr + size) set the carry bit?
- * 3. Is (addr + size) a negative number (i.e. >= 0x80000000)?
- *
- * If yes on the first check, access is granted.
- * If no on any of the others, access is denied.
- */
- #define __range_ok(addr, size) \
- (test_thread_flag(TIF_USERSPACE) \
- && (((unsigned long)(addr) >= 0x80000000) \
- || ((unsigned long)(size) > 0x80000000) \
- || (((unsigned long)(addr) + (unsigned long)(size)) > 0x80000000)))
- #define access_ok(type, addr, size) (likely(__range_ok(addr, size) == 0))
- /* Generic arbitrary sized copy. Return the number of bytes NOT copied */
- extern __kernel_size_t __copy_user(void *to, const void *from,
- __kernel_size_t n);
- extern __kernel_size_t copy_to_user(void __user *to, const void *from,
- __kernel_size_t n);
- extern __kernel_size_t copy_from_user(void *to, const void __user *from,
- __kernel_size_t n);
- static inline __kernel_size_t __copy_to_user(void __user *to, const void *from,
- __kernel_size_t n)
- {
- return __copy_user((void __force *)to, from, n);
- }
- static inline __kernel_size_t __copy_from_user(void *to,
- const void __user *from,
- __kernel_size_t n)
- {
- return __copy_user(to, (const void __force *)from, n);
- }
- #define __copy_to_user_inatomic __copy_to_user
- #define __copy_from_user_inatomic __copy_from_user
- /*
- * put_user: - Write a simple value into user space.
- * @x: Value to copy to user space.
- * @ptr: Destination address, in user space.
- *
- * Context: User context only. This function may sleep.
- *
- * This macro copies a single simple value from kernel space to user
- * space. It supports simple types like char and int, but not larger
- * data types like structures or arrays.
- *
- * @ptr must have pointer-to-simple-variable type, and @x must be assignable
- * to the result of dereferencing @ptr.
- *
- * Returns zero on success, or -EFAULT on error.
- */
- #define put_user(x,ptr) \
- __put_user_check((x),(ptr),sizeof(*(ptr)))
- /*
- * get_user: - Get a simple variable from user space.
- * @x: Variable to store result.
- * @ptr: Source address, in user space.
- *
- * Context: User context only. This function may sleep.
- *
- * This macro copies a single simple variable from user space to kernel
- * space. It supports simple types like char and int, but not larger
- * data types like structures or arrays.
- *
- * @ptr must have pointer-to-simple-variable type, and the result of
- * dereferencing @ptr must be assignable to @x without a cast.
- *
- * Returns zero on success, or -EFAULT on error.
- * On error, the variable @x is set to zero.
- */
- #define get_user(x,ptr) \
- __get_user_check((x),(ptr),sizeof(*(ptr)))
- /*
- * __put_user: - Write a simple value into user space, with less checking.
- * @x: Value to copy to user space.
- * @ptr: Destination address, in user space.
- *
- * Context: User context only. This function may sleep.
- *
- * This macro copies a single simple value from kernel space to user
- * space. It supports simple types like char and int, but not larger
- * data types like structures or arrays.
- *
- * @ptr must have pointer-to-simple-variable type, and @x must be assignable
- * to the result of dereferencing @ptr.
- *
- * Caller must check the pointer with access_ok() before calling this
- * function.
- *
- * Returns zero on success, or -EFAULT on error.
- */
- #define __put_user(x,ptr) \
- __put_user_nocheck((x),(ptr),sizeof(*(ptr)))
- /*
- * __get_user: - Get a simple variable from user space, with less checking.
- * @x: Variable to store result.
- * @ptr: Source address, in user space.
- *
- * Context: User context only. This function may sleep.
- *
- * This macro copies a single simple variable from user space to kernel
- * space. It supports simple types like char and int, but not larger
- * data types like structures or arrays.
- *
- * @ptr must have pointer-to-simple-variable type, and the result of
- * dereferencing @ptr must be assignable to @x without a cast.
- *
- * Caller must check the pointer with access_ok() before calling this
- * function.
- *
- * Returns zero on success, or -EFAULT on error.
- * On error, the variable @x is set to zero.
- */
- #define __get_user(x,ptr) \
- __get_user_nocheck((x),(ptr),sizeof(*(ptr)))
- extern int __get_user_bad(void);
- extern int __put_user_bad(void);
- #define __get_user_nocheck(x, ptr, size) \
- ({ \
- unsigned long __gu_val = 0; \
- int __gu_err = 0; \
- \
- switch (size) { \
- case 1: __get_user_asm("ub", __gu_val, ptr, __gu_err); break; \
- case 2: __get_user_asm("uh", __gu_val, ptr, __gu_err); break; \
- case 4: __get_user_asm("w", __gu_val, ptr, __gu_err); break; \
- default: __gu_err = __get_user_bad(); break; \
- } \
- \
- x = (typeof(*(ptr)))__gu_val; \
- __gu_err; \
- })
- #define __get_user_check(x, ptr, size) \
- ({ \
- unsigned long __gu_val = 0; \
- const typeof(*(ptr)) __user * __gu_addr = (ptr); \
- int __gu_err = 0; \
- \
- if (access_ok(VERIFY_READ, __gu_addr, size)) { \
- switch (size) { \
- case 1: \
- __get_user_asm("ub", __gu_val, __gu_addr, \
- __gu_err); \
- break; \
- case 2: \
- __get_user_asm("uh", __gu_val, __gu_addr, \
- __gu_err); \
- break; \
- case 4: \
- __get_user_asm("w", __gu_val, __gu_addr, \
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