18c2ecf20Sopenharmony_ci// SPDX-License-Identifier: GPL-2.0-only
28c2ecf20Sopenharmony_ci/*
38c2ecf20Sopenharmony_ci * Copyright (C) 2013 Richard Weinberger <richrd@nod.at>
48c2ecf20Sopenharmony_ci */
58c2ecf20Sopenharmony_ci
68c2ecf20Sopenharmony_ci#include <linux/uaccess.h>
78c2ecf20Sopenharmony_ci#include <linux/kernel.h>
88c2ecf20Sopenharmony_ci#include <os.h>
98c2ecf20Sopenharmony_ci
108c2ecf20Sopenharmony_cibool copy_from_kernel_nofault_allowed(const void *src, size_t size)
118c2ecf20Sopenharmony_ci{
128c2ecf20Sopenharmony_ci	void *psrc = (void *)rounddown((unsigned long)src, PAGE_SIZE);
138c2ecf20Sopenharmony_ci
148c2ecf20Sopenharmony_ci	if ((unsigned long)src < PAGE_SIZE || size <= 0)
158c2ecf20Sopenharmony_ci		return false;
168c2ecf20Sopenharmony_ci	if (os_mincore(psrc, size + src - psrc) <= 0)
178c2ecf20Sopenharmony_ci		return false;
188c2ecf20Sopenharmony_ci	return true;
198c2ecf20Sopenharmony_ci}
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