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 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