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-rw-r--r--include/asm-avr32/uaccess.h335
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diff --git a/include/asm-avr32/uaccess.h b/include/asm-avr32/uaccess.h
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+++ b/include/asm-avr32/uaccess.h
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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))
+
+static inline int
+verify_area(int type, const void __user *addr, unsigned long size)
+{
+ return access_ok(type, addr, size) ? 0 : -EFAULT;
+}
+
+/* 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) \
+({ \
+ typeof(*(ptr)) __gu_val = (typeof(*(ptr)) __force)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; \
+ case 8: __get_user_asm("d", __gu_val, ptr, __gu_err); break; \
+ default: __gu_err = __get_user_bad(); break; \
+ } \
+ \
+ x = __gu_val; \
+ __gu_err; \
+})
+
+#define __get_user_check(x, ptr, size) \
+({ \
+ typeof(*(ptr)) __gu_val = (typeof(*(ptr)) __force)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, \
+ __gu_err); \
+ break; \
+ case 8: \
+ __get_user_asm("d", __gu_val, __gu_addr, \
+ __gu_err); \
+ break; \
+ default: \
+ __gu_err = __get_user_bad(); \
+ break; \
+ } \
+ } else { \
+ __gu_err = -EFAULT; \
+ } \
+ x = __gu_val; \
+ __gu_err; \
+})
+
+#define __get_user_asm(suffix, __gu_val, ptr, __gu_err) \
+ asm volatile( \
+ "1: ld." suffix " %1, %3 \n" \
+ "2: \n" \
+ " .section .fixup, \"ax\" \n" \
+ "3: mov %0, %4 \n" \
+ " rjmp 2b \n" \
+ " .previous \n" \
+ " .section __ex_table, \"a\" \n" \
+ " .long 1b, 3b \n" \
+ " .previous \n" \
+ : "=r"(__gu_err), "=r"(__gu_val) \
+ : "0"(__gu_err), "m"(*(ptr)), "i"(-EFAULT))
+
+#define __put_user_nocheck(x, ptr, size) \
+({ \
+ typeof(*(ptr)) __pu_val; \
+ int __pu_err = 0; \
+ \
+ __pu_val = (x); \
+ switch (size) { \
+ case 1: __put_user_asm("b", ptr, __pu_val, __pu_err); break; \
+ case 2: __put_user_asm("h", ptr, __pu_val, __pu_err); break; \
+ case 4: __put_user_asm("w", ptr, __pu_val, __pu_err); break; \
+ case 8: __put_user_asm("d", ptr, __pu_val, __pu_err); break; \
+ default: __pu_err = __put_user_bad(); break; \
+ } \
+ __pu_err; \
+})
+
+#define __put_user_check(x, ptr, size) \
+({ \
+ typeof(*(ptr)) __pu_val; \
+ typeof(*(ptr)) __user *__pu_addr = (ptr); \
+ int __pu_err = 0; \
+ \
+ __pu_val = (x); \
+ if (access_ok(VERIFY_WRITE, __pu_addr, size)) { \
+ switch (size) { \
+ case 1: \
+ __put_user_asm("b", __pu_addr, __pu_val, \
+ __pu_err); \
+ break; \
+ case 2: \
+ __put_user_asm("h", __pu_addr, __pu_val, \
+ __pu_err); \
+ break; \
+ case 4: \
+ __put_user_asm("w", __pu_addr, __pu_val, \
+ __pu_err); \
+ break; \
+ case 8: \
+ __put_user_asm("d", __pu_addr, __pu_val, \
+ __pu_err); \
+ break; \
+ default: \
+ __pu_err = __put_user_bad(); \
+ break; \
+ } \
+ } else { \
+ __pu_err = -EFAULT; \
+ } \
+ __pu_err; \
+})
+
+#define __put_user_asm(suffix, ptr, __pu_val, __gu_err) \
+ asm volatile( \
+ "1: st." suffix " %1, %3 \n" \
+ "2: \n" \
+ " .section .fixup, \"ax\" \n" \
+ "3: mov %0, %4 \n" \
+ " rjmp 2b \n" \
+ " .previous \n" \
+ " .section __ex_table, \"a\" \n" \
+ " .long 1b, 3b \n" \
+ " .previous \n" \
+ : "=r"(__gu_err), "=m"(*(ptr)) \
+ : "0"(__gu_err), "r"(__pu_val), "i"(-EFAULT))
+
+extern __kernel_size_t clear_user(void __user *addr, __kernel_size_t size);
+extern __kernel_size_t __clear_user(void __user *addr, __kernel_size_t size);
+
+extern long strncpy_from_user(char *dst, const char __user *src, long count);
+extern long __strncpy_from_user(char *dst, const char __user *src, long count);
+
+extern long strnlen_user(const char __user *__s, long __n);
+extern long __strnlen_user(const char __user *__s, long __n);
+
+#define strlen_user(s) strnlen_user(s, ~0UL >> 1)
+
+struct exception_table_entry
+{
+ unsigned long insn, fixup;
+};
+
+#endif /* __ASM_AVR32_UACCESS_H */
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