1caab277bSThomas Gleixner // SPDX-License-Identifier: GPL-2.0-only 21d18c47cSCatalin Marinas /* 31d18c47cSCatalin Marinas * Based on arch/arm/mm/copypage.c 41d18c47cSCatalin Marinas * 51d18c47cSCatalin Marinas * Copyright (C) 2002 Deep Blue Solutions Ltd, All Rights Reserved. 61d18c47cSCatalin Marinas * Copyright (C) 2012 ARM Ltd. 71d18c47cSCatalin Marinas */ 81d18c47cSCatalin Marinas 92563776bSVincenzo Frascino #include <linux/bitops.h> 101d18c47cSCatalin Marinas #include <linux/mm.h> 111d18c47cSCatalin Marinas 121d18c47cSCatalin Marinas #include <asm/page.h> 131d18c47cSCatalin Marinas #include <asm/cacheflush.h> 142563776bSVincenzo Frascino #include <asm/cpufeature.h> 152563776bSVincenzo Frascino #include <asm/mte.h> 161d18c47cSCatalin Marinas 172563776bSVincenzo Frascino void copy_highpage(struct page *to, struct page *from) 181d18c47cSCatalin Marinas { 192563776bSVincenzo Frascino struct page *kto = page_address(to); 202563776bSVincenzo Frascino struct page *kfrom = page_address(from); 212563776bSVincenzo Frascino 221d18c47cSCatalin Marinas copy_page(kto, kfrom); 232563776bSVincenzo Frascino 242563776bSVincenzo Frascino if (system_supports_mte() && test_bit(PG_mte_tagged, &from->flags)) { 252563776bSVincenzo Frascino set_bit(PG_mte_tagged, &to->flags); 26*e5b8d921SVincenzo Frascino page_kasan_tag_reset(to); 27*e5b8d921SVincenzo Frascino /* 28*e5b8d921SVincenzo Frascino * We need smp_wmb() in between setting the flags and clearing the 29*e5b8d921SVincenzo Frascino * tags because if another thread reads page->flags and builds a 30*e5b8d921SVincenzo Frascino * tagged address out of it, there is an actual dependency to the 31*e5b8d921SVincenzo Frascino * memory access, but on the current thread we do not guarantee that 32*e5b8d921SVincenzo Frascino * the new page->flags are visible before the tags were updated. 33*e5b8d921SVincenzo Frascino */ 34*e5b8d921SVincenzo Frascino smp_wmb(); 352563776bSVincenzo Frascino mte_copy_page_tags(kto, kfrom); 361d18c47cSCatalin Marinas } 372563776bSVincenzo Frascino } 382563776bSVincenzo Frascino EXPORT_SYMBOL(copy_highpage); 392563776bSVincenzo Frascino 402563776bSVincenzo Frascino void copy_user_highpage(struct page *to, struct page *from, 412563776bSVincenzo Frascino unsigned long vaddr, struct vm_area_struct *vma) 422563776bSVincenzo Frascino { 432563776bSVincenzo Frascino copy_highpage(to, from); 442563776bSVincenzo Frascino flush_dcache_page(to); 452563776bSVincenzo Frascino } 462563776bSVincenzo Frascino EXPORT_SYMBOL_GPL(copy_user_highpage); 47