Initial commit

arch/um/include/asm/uaccess.h

@@ -0,0 +1,178 @@
+/* 
+ * Copyright (C) 2002 Jeff Dike (jdike@karaya.com)
+ * Licensed under the GPL
+ */
+
+#ifndef __UM_UACCESS_H
+#define __UM_UACCESS_H
+
+/* thread_info has a mm_segment_t in it, so put the definition up here */
+typedef struct {
+	unsigned long seg;
+} mm_segment_t;
+
+#include <linux/thread_info.h>
+#include <linux/errno.h>
+#include <asm/processor.h>
+#include <asm/elf.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(0xFFFFFFFF)
+#define USER_DS		MAKE_MM_SEG(TASK_SIZE)
+
+#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 __under_task_size(addr, size) \
+	(((unsigned long) (addr) < TASK_SIZE) && \
+	 (((unsigned long) (addr) + (size)) < TASK_SIZE))
+
+#define __access_ok_vsyscall(type, addr, size) \
+	 ((type == VERIFY_READ) && \
+	  ((unsigned long) (addr) >= FIXADDR_USER_START) && \
+	  ((unsigned long) (addr) + (size) <= FIXADDR_USER_END) && \
+	  ((unsigned long) (addr) + (size) >= (unsigned long)(addr)))
+
+#define __addr_range_nowrap(addr, size) \
+	((unsigned long) (addr) <= ((unsigned long) (addr) + (size)))
+
+#define access_ok(type, addr, size) \
+	(__addr_range_nowrap(addr, size) && \
+	 (__under_task_size(addr, size) || \
+	  __access_ok_vsyscall(type, addr, size) || \
+	  segment_eq(get_fs(), KERNEL_DS)))
+
+extern int copy_from_user(void *to, const void __user *from, int n);
+extern int copy_to_user(void __user *to, const void *from, int n);
+
+/*
+ * strncpy_from_user: - Copy a NUL terminated string from userspace.
+ * @dst:   Destination address, in kernel space.  This buffer must be at
+ *         least @count bytes long.
+ * @src:   Source address, in user space.
+ * @count: Maximum number of bytes to copy, including the trailing NUL.
+ *
+ * Copies a NUL-terminated string from userspace to kernel space.
+ *
+ * On success, returns the length of the string (not including the trailing
+ * NUL).
+ *
+ * If access to userspace fails, returns -EFAULT (some data may have been
+ * copied).
+ *
+ * If @count is smaller than the length of the string, copies @count bytes
+ * and returns @count.
+ */
+
+extern int strncpy_from_user(char *dst, const char __user *src, int count);
+
+/*
+ * __clear_user: - Zero a block of memory in user space, with less checking.
+ * @to:   Destination address, in user space.
+ * @n:    Number of bytes to zero.
+ *
+ * Zero a block of memory in user space.  Caller must check
+ * the specified block with access_ok() before calling this function.
+ *
+ * Returns number of bytes that could not be cleared.
+ * On success, this will be zero.
+ */
+extern int __clear_user(void __user *mem, int len);
+
+/*
+ * clear_user: - Zero a block of memory in user space.
+ * @to:   Destination address, in user space.
+ * @n:    Number of bytes to zero.
+ *
+ * Zero a block of memory in user space.
+ *
+ * Returns number of bytes that could not be cleared.
+ * On success, this will be zero.
+ */
+extern int clear_user(void __user *mem, int len);
+
+/*
+ * strlen_user: - Get the size of a string in user space.
+ * @str: The string to measure.
+ * @n:   The maximum valid length
+ *
+ * Get the size of a NUL-terminated string in user space.
+ *
+ * Returns the size of the string INCLUDING the terminating NUL.
+ * On exception, returns 0.
+ * If the string is too long, returns a value greater than @n.
+ */
+extern int strnlen_user(const void __user *str, int len);
+
+#define __copy_from_user(to, from, n) copy_from_user(to, from, n)
+
+#define __copy_to_user(to, from, n) copy_to_user(to, from, n)
+
+#define __copy_to_user_inatomic __copy_to_user
+#define __copy_from_user_inatomic __copy_from_user
+
+#define __get_user(x, ptr) \
+({ \
+	const __typeof__(*(ptr)) __user *__private_ptr = (ptr);	\
+	__typeof__(x) __private_val;			\
+	int __private_ret = -EFAULT;			\
+	(x) = (__typeof__(*(__private_ptr)))0;				\
+	if (__copy_from_user((__force void *)&__private_val, (__private_ptr),\
+			     sizeof(*(__private_ptr))) == 0) {		\
+		(x) = (__typeof__(*(__private_ptr))) __private_val;	\
+		__private_ret = 0;					\
+	}								\
+	__private_ret;							\
+}) 
+
+#define get_user(x, ptr) \
+({ \
+        const __typeof__((*(ptr))) __user *private_ptr = (ptr); \
+        (access_ok(VERIFY_READ, private_ptr, sizeof(*private_ptr)) ? \
+	 __get_user(x, private_ptr) : ((x) = (__typeof__(*ptr))0, -EFAULT)); \
+})
+
+#define __put_user(x, ptr) \
+({ \
+        __typeof__(*(ptr)) __user *__private_ptr = ptr; \
+        __typeof__(*(__private_ptr)) __private_val; \
+        int __private_ret = -EFAULT; \
+        __private_val = (__typeof__(*(__private_ptr))) (x); \
+        if (__copy_to_user((__private_ptr), &__private_val, \
+			   sizeof(*(__private_ptr))) == 0) { \
+		__private_ret = 0; \
+	} \
+        __private_ret; \
+})
+
+#define put_user(x, ptr) \
+({ \
+        __typeof__(*(ptr)) __user *private_ptr = (ptr); \
+        (access_ok(VERIFY_WRITE, private_ptr, sizeof(*private_ptr)) ? \
+	 __put_user(x, private_ptr) : -EFAULT); \
+})
+
+#define strlen_user(str) strnlen_user(str, ~0U >> 1)
+
+struct exception_table_entry
+{
+        unsigned long insn;
+	unsigned long fixup;
+};
+
+#endif