1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Based on arch/arm/mm/copypage.c 4 * 5 * Copyright (C) 2002 Deep Blue Solutions Ltd, All Rights Reserved. 6 * Copyright (C) 2012 ARM Ltd. 7 */ 8 9 #include <linux/bitops.h> 10 #include <linux/mm.h> 11 12 #include <asm/page.h> 13 #include <asm/cacheflush.h> 14 #include <asm/cpufeature.h> 15 #include <asm/mte.h> 16 17 void copy_highpage(struct page *to, struct page *from) 18 { 19 void *kto = page_address(to); 20 void *kfrom = page_address(from); 21 struct folio *src = page_folio(from); 22 struct folio *dst = page_folio(to); 23 unsigned int i, nr_pages; 24 25 copy_page(kto, kfrom); 26 27 if (kasan_hw_tags_enabled()) 28 page_kasan_tag_reset(to); 29 30 if (!system_supports_mte()) 31 return; 32 33 if (folio_test_hugetlb(src) && 34 folio_test_hugetlb_mte_tagged(src)) { 35 if (!folio_try_hugetlb_mte_tagging(dst)) 36 return; 37 38 /* 39 * Populate tags for all subpages. 40 * 41 * Don't assume the first page is head page since 42 * huge page copy may start from any subpage. 43 */ 44 nr_pages = folio_nr_pages(src); 45 for (i = 0; i < nr_pages; i++) { 46 kfrom = page_address(folio_page(src, i)); 47 kto = page_address(folio_page(dst, i)); 48 mte_copy_page_tags(kto, kfrom); 49 } 50 folio_set_hugetlb_mte_tagged(dst); 51 } else if (page_mte_tagged(from)) { 52 /* It's a new page, shouldn't have been tagged yet */ 53 WARN_ON_ONCE(!try_page_mte_tagging(to)); 54 55 mte_copy_page_tags(kto, kfrom); 56 set_page_mte_tagged(to); 57 } 58 } 59 EXPORT_SYMBOL(copy_highpage); 60 61 void copy_user_highpage(struct page *to, struct page *from, 62 unsigned long vaddr, struct vm_area_struct *vma) 63 { 64 copy_highpage(to, from); 65 flush_dcache_page(to); 66 } 67 EXPORT_SYMBOL_GPL(copy_user_highpage); 68