fedora core 6 1.2949 + vserver 2.2.0

[linux-2.6.git] / arch / um / include / um_uaccess.h

diff --git a/arch/um/include/um_uaccess.h b/arch/um/include/um_uaccess.h
index 41afa3a..5126a99 100644 (file)
--- a/arch/um/include/um_uaccess.h
+++ b/arch/um/include/um_uaccess.h
@@ -6,55 +6,118 @@
 #ifndef __ARCH_UM_UACCESS_H
 #define __ARCH_UM_UACCESS_H
 
-#include "linux/config.h"
 #include "choose-mode.h"
 
 #ifdef CONFIG_MODE_TT
-#include "../kernel/tt/include/uaccess.h"
+#include "uaccess-tt.h"
 #endif
 
 #ifdef CONFIG_MODE_SKAS
-#include "../kernel/skas/include/uaccess.h"
+#include "uaccess-skas.h"
 #endif
 
-#define access_ok(type, addr, size) \
-       CHOOSE_MODE_PROC(access_ok_tt, access_ok_skas, type, addr, size)
+#include "asm/fixmap.h"
 
-static inline int verify_area(int type, const void * addr, unsigned long size)
-{
-       return(CHOOSE_MODE_PROC(verify_area_tt, verify_area_skas, type, addr,
-                               size));
-}
+#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)))
 
-static inline int copy_from_user(void *to, const void *from, int n)
+#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) || \
+         CHOOSE_MODE_PROC(access_ok_tt, access_ok_skas, type, addr, size)))
+
+static inline int copy_from_user(void *to, const void __user *from, int n)
 {
        return(CHOOSE_MODE_PROC(copy_from_user_tt, copy_from_user_skas, to,
                                from, n));
 }
 
-static inline int copy_to_user(void *to, const void *from, int n)
+static inline int copy_to_user(void __user *to, const void *from, int n)
 {
        return(CHOOSE_MODE_PROC(copy_to_user_tt, copy_to_user_skas, to, 
                                from, n));
 }
 
-static inline int strncpy_from_user(char *dst, const char *src, int count)
+/*
+ * 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.
+ */
+
+static inline int strncpy_from_user(char *dst, const char __user *src, int count)
 {
        return(CHOOSE_MODE_PROC(strncpy_from_user_tt, strncpy_from_user_skas,
                                dst, src, 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.
+ */
 static inline int __clear_user(void *mem, int len)
 {
        return(CHOOSE_MODE_PROC(__clear_user_tt, __clear_user_skas, mem, len));
 }
 
-static inline int clear_user(void *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.
+ */
+static inline int clear_user(void __user *mem, int len)
 {
        return(CHOOSE_MODE_PROC(clear_user_tt, clear_user_skas, mem, len));
 }
 
-static inline int strnlen_user(const void *str, 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.
+ */
+static inline int strnlen_user(const void __user *str, long len)
 {
        return(CHOOSE_MODE_PROC(strnlen_user_tt, strnlen_user_skas, str, len));
 }