1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3 * Copyright (C) 2002 Jeff Dike (jdike@karaya.com)
4 * Copyright (C) 2015 Richard Weinberger (richard@nod.at)
5 */
6
7 #ifndef __UM_UACCESS_H
8 #define __UM_UACCESS_H
9
10 #include <asm/elf.h>
11 #include <linux/unaligned.h>
12
13 #define __under_task_size(addr, size) \
14 (((unsigned long) (addr) < TASK_SIZE) && \
15 (((unsigned long) (addr) + (size)) < TASK_SIZE))
16
17 #define __access_ok_vsyscall(addr, size) \
18 (((unsigned long) (addr) >= FIXADDR_USER_START) && \
19 ((unsigned long) (addr) + (size) <= FIXADDR_USER_END) && \
20 ((unsigned long) (addr) + (size) >= (unsigned long)(addr)))
21
22 #define __addr_range_nowrap(addr, size) \
23 ((unsigned long) (addr) <= ((unsigned long) (addr) + (size)))
24
25 extern unsigned long raw_copy_from_user(void *to, const void __user *from, unsigned long n);
26 extern unsigned long raw_copy_to_user(void __user *to, const void *from, unsigned long n);
27 extern unsigned long __clear_user(void __user *mem, unsigned long len);
28 static inline int __access_ok(const void __user *ptr, unsigned long size);
29
30 /* Teach asm-generic/uaccess.h that we have C functions for these. */
31 #define __access_ok __access_ok
32 #define __clear_user __clear_user
33
34 #define INLINE_COPY_FROM_USER
35 #define INLINE_COPY_TO_USER
36
37 #include <asm-generic/uaccess.h>
38
__access_ok(const void __user * ptr,unsigned long size)39 static inline int __access_ok(const void __user *ptr, unsigned long size)
40 {
41 unsigned long addr = (unsigned long)ptr;
42 return __addr_range_nowrap(addr, size) &&
43 (__under_task_size(addr, size) ||
44 __access_ok_vsyscall(addr, size));
45 }
46
47 /* no pagefaults for kernel addresses in um */
48 #define __get_kernel_nofault(dst, src, type, err_label) \
49 do { \
50 *((type *)dst) = get_unaligned((type *)(src)); \
51 if (0) /* make sure the label looks used to the compiler */ \
52 goto err_label; \
53 } while (0)
54
55 #define __put_kernel_nofault(dst, src, type, err_label) \
56 do { \
57 put_unaligned(*((type *)src), (type *)(dst)); \
58 if (0) /* make sure the label looks used to the compiler */ \
59 goto err_label; \
60 } while (0)
61
62 #endif
63