1 // SPDX-License-Identifier: GPL-2.0-only
3 * Based on arch/arm/mm/copypage.c
5 * Copyright (C) 2002 Deep Blue Solutions Ltd, All Rights Reserved.
6 * Copyright (C) 2012 ARM Ltd.
9 #include <linux/bitops.h>
13 #include <asm/cacheflush.h>
14 #include <asm/cpufeature.h>
17 void copy_highpage(struct page *to, struct page *from)
19 void *kto = page_address(to);
20 void *kfrom = page_address(from);
22 copy_page(kto, kfrom);
24 page_kasan_tag_reset(to);
26 if (system_supports_mte() && test_bit(PG_mte_tagged, &from->flags)) {
27 set_bit(PG_mte_tagged, &to->flags);
29 * We need smp_wmb() in between setting the flags and clearing the
30 * tags because if another thread reads page->flags and builds a
31 * tagged address out of it, there is an actual dependency to the
32 * memory access, but on the current thread we do not guarantee that
33 * the new page->flags are visible before the tags were updated.
36 mte_copy_page_tags(kto, kfrom);
39 EXPORT_SYMBOL(copy_highpage);
41 void copy_user_highpage(struct page *to, struct page *from,
42 unsigned long vaddr, struct vm_area_struct *vma)
44 copy_highpage(to, from);
45 flush_dcache_page(to);
47 EXPORT_SYMBOL_GPL(copy_user_highpage);