xref: /linux/arch/um/kernel/maccess.c (revision b83deaa741558babf4b8d51d34f6637ccfff1b26)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) 2013 Richard Weinberger <richrd@nod.at>
4  */
5 
6 #include <linux/uaccess.h>
7 #include <linux/kernel.h>
8 #include <os.h>
9 
10 bool copy_from_kernel_nofault_allowed(const void *src, size_t size)
11 {
12 	void *psrc = (void *)rounddown((unsigned long)src, PAGE_SIZE);
13 
14 	if ((unsigned long)src < PAGE_SIZE || size <= 0)
15 		return false;
16 	if (os_mincore(psrc, size + src - psrc) <= 0)
17 		return false;
18 	return true;
19 }
20