From 8569c9140bd41089f9b6be8837ca421102714a90 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Sun, 17 Aug 2008 13:48:37 -0400 Subject: x86, um: take arch/um/include/* out of the way We can't just plop asm/* into it - userland helpers are built with it in search path and seeing asm/* show up there suddenly would be a bad idea. Signed-off-by: Al Viro Signed-off-by: H. Peter Anvin --- arch/um/include/shared/um_uaccess.h | 97 +++++++++++++++++++++++++++++++++++++ 1 file changed, 97 insertions(+) create mode 100644 arch/um/include/shared/um_uaccess.h (limited to 'arch/um/include/shared/um_uaccess.h') diff --git a/arch/um/include/shared/um_uaccess.h b/arch/um/include/shared/um_uaccess.h new file mode 100644 index 000000000000..45c04999d670 --- /dev/null +++ b/arch/um/include/shared/um_uaccess.h @@ -0,0 +1,97 @@ +/* + * Copyright (C) 2002 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com) + * Licensed under the GPL + */ + +#ifndef __ARCH_UM_UACCESS_H +#define __ARCH_UM_UACCESS_H + +#include +#include +#include "sysdep/archsetjmp.h" + +#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); + +extern int __do_copy_to_user(void *to, const void *from, int n, + void **fault_addr, jmp_buf **fault_catcher); + +/* + * 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); + +#endif -- cgit v1.2.3