1 files changed, 56 insertions, 16 deletions

diff --git a/arch/arm64/mm/copypage.c b/arch/arm64/mm/copypage.c
index 9aecbace4128..cd5912ba617b 100644
--- a/arch/arm64/mm/copypage.c
+++ b/arch/arm64/mm/copypage.c
@@ -1,34 +1,74 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /*
  * Based on arch/arm/mm/copypage.c
  *
  * Copyright (C) 2002 Deep Blue Solutions Ltd, All Rights Reserved.
  * Copyright (C) 2012 ARM Ltd.
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
+#include <linux/bitops.h>
 #include <linux/mm.h>
 
 #include <asm/page.h>
 #include <asm/cacheflush.h>
+#include <asm/cpufeature.h>
+#include <asm/mte.h>
 
-void __cpu_copy_user_page(void *kto, const void *kfrom, unsigned long vaddr)
+void copy_highpage(struct page *to, struct page *from)
 {
+	void *kto = page_address(to);
+	void *kfrom = page_address(from);
+	struct folio *src = page_folio(from);
+	struct folio *dst = page_folio(to);
+	unsigned int i, nr_pages;
+
 	copy_page(kto, kfrom);
-	__flush_dcache_area(kto, PAGE_SIZE);
+
+	if (kasan_hw_tags_enabled())
+		page_kasan_tag_reset(to);
+
+	if (!system_supports_mte())
+		return;
+
+	if (folio_test_hugetlb(src)) {
+		if (!folio_test_hugetlb_mte_tagged(src) ||
+		    from != folio_page(src, 0))
+			return;
+
+		folio_try_hugetlb_mte_tagging(dst);
+
+		/*
+		 * Populate tags for all subpages.
+		 *
+		 * Don't assume the first page is head page since
+		 * huge page copy may start from any subpage.
+		 */
+		nr_pages = folio_nr_pages(src);
+		for (i = 0; i < nr_pages; i++) {
+			kfrom = page_address(folio_page(src, i));
+			kto = page_address(folio_page(dst, i));
+			mte_copy_page_tags(kto, kfrom);
+		}
+		folio_set_hugetlb_mte_tagged(dst);
+	} else if (page_mte_tagged(from)) {
+		/*
+		 * Most of the time it's a new page that shouldn't have been
+		 * tagged yet. However, folio migration can end up reusing the
+		 * same page without untagging it. Ignore the warning if the
+		 * page is already tagged.
+		 */
+		try_page_mte_tagging(to);
+
+		mte_copy_page_tags(kto, kfrom);
+		set_page_mte_tagged(to);
+	}
 }
+EXPORT_SYMBOL(copy_highpage);
 
-void __cpu_clear_user_page(void *kaddr, unsigned long vaddr)
+void copy_user_highpage(struct page *to, struct page *from,
+			unsigned long vaddr, struct vm_area_struct *vma)
 {
-	clear_page(kaddr);
+	copy_highpage(to, from);
+	flush_dcache_page(to);
 }
+EXPORT_SYMBOL_GPL(copy_user_highpage);