uaccess_flushcache.c

 1// SPDX-License-Identifier: GPL-2.0-only
 2/*
 3 * Copyright (C) 2017 ARM Ltd.
 4 */
 5
 6#include <linux/uaccess.h>
 7#include <asm/barrier.h>
 8#include <asm/cacheflush.h>
 9
10void memcpy_flushcache(void *dst, const void *src, size_t cnt)
11{
12	/*
13	 * We assume this should not be called with @dst pointing to
14	 * non-cacheable memory, such that we don't need an explicit
15	 * barrier to order the cache maintenance against the memcpy.
16	 */
17	memcpy(dst, src, cnt);
18	dcache_clean_pop((unsigned long)dst, (unsigned long)dst + cnt);
19}
20EXPORT_SYMBOL_GPL(memcpy_flushcache);
21
22unsigned long __copy_user_flushcache(void *to, const void __user *from,
23				     unsigned long n)
24{
25	unsigned long rc;
26
27	rc = raw_copy_from_user(to, from, n);
28
29	/* See above */
30	dcache_clean_pop((unsigned long)to, (unsigned long)to + n - rc);
31	return rc;
32}