From 4d510f3da4c216d4c2695395f67aec38e2aa6cc7 Mon Sep 17 00:00:00 2001 From: "Matthew Wilcox (Oracle)" Date: Wed, 11 Jan 2023 14:28:54 +0000 Subject: [PATCH] mm: add folio_add_new_anon_rmap() In contrast to other rmap functions, page_add_new_anon_rmap() is always called with a freshly allocated page. That means it can't be called with a tail page. Turn page_add_new_anon_rmap() into folio_add_new_anon_rmap() and add a page_add_new_anon_rmap() wrapper. Callers can be converted individually. [akpm@linux-foundation.org: fix NOMMU build. page_add_new_anon_rmap() requires CONFIG_MMU] [willy@infradead.org: folio-compat.c needs rmap.h] Link: https://lkml.kernel.org/r/20230111142915.1001531-9-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) Signed-off-by: Andrew Morton --- include/linux/rmap.h | 2 ++ mm/folio-compat.c | 11 +++++++++++ mm/rmap.c | 37 ++++++++++++++++++------------------- 3 files changed, 31 insertions(+), 19 deletions(-) diff --git a/include/linux/rmap.h b/include/linux/rmap.h index bd3504d..aa682a2 100644 --- a/include/linux/rmap.h +++ b/include/linux/rmap.h @@ -194,6 +194,8 @@ void page_add_anon_rmap(struct page *, struct vm_area_struct *, unsigned long address, rmap_t flags); void page_add_new_anon_rmap(struct page *, struct vm_area_struct *, unsigned long address); +void folio_add_new_anon_rmap(struct folio *, struct vm_area_struct *, + unsigned long address); void page_add_file_rmap(struct page *, struct vm_area_struct *, bool compound); void page_remove_rmap(struct page *, struct vm_area_struct *, diff --git a/mm/folio-compat.c b/mm/folio-compat.c index 69ed257..18c48b5 100644 --- a/mm/folio-compat.c +++ b/mm/folio-compat.c @@ -6,6 +6,7 @@ #include #include +#include #include #include "internal.h" @@ -123,3 +124,13 @@ void putback_lru_page(struct page *page) { folio_putback_lru(page_folio(page)); } + +#ifdef CONFIG_MMU +void page_add_new_anon_rmap(struct page *page, struct vm_area_struct *vma, + unsigned long address) +{ + VM_BUG_ON_PAGE(PageTail(page), page); + + return folio_add_new_anon_rmap((struct folio *)page, vma, address); +} +#endif diff --git a/mm/rmap.c b/mm/rmap.c index 430c066..513e23e 100644 --- a/mm/rmap.c +++ b/mm/rmap.c @@ -1264,41 +1264,40 @@ void page_add_anon_rmap(struct page *page, struct vm_area_struct *vma, } /** - * page_add_new_anon_rmap - add mapping to a new anonymous page - * @page: the page to add the mapping to + * folio_add_new_anon_rmap - Add mapping to a new anonymous folio. + * @folio: The folio to add the mapping to. * @vma: the vm area in which the mapping is added * @address: the user virtual address mapped * - * If it's a compound page, it is accounted as a compound page. As the page - * is new, it's assume to get mapped exclusively by a single process. - * - * Same as page_add_anon_rmap but must only be called on *new* pages. + * Like page_add_anon_rmap() but must only be called on *new* folios. * This means the inc-and-test can be bypassed. - * Page does not have to be locked. + * The folio does not have to be locked. + * + * If the folio is large, it is accounted as a THP. As the folio + * is new, it's assumed to be mapped exclusively by a single process. */ -void page_add_new_anon_rmap(struct page *page, - struct vm_area_struct *vma, unsigned long address) +void folio_add_new_anon_rmap(struct folio *folio, struct vm_area_struct *vma, + unsigned long address) { int nr; VM_BUG_ON_VMA(address < vma->vm_start || address >= vma->vm_end, vma); - __SetPageSwapBacked(page); + __folio_set_swapbacked(folio); - if (likely(!PageCompound(page))) { + if (likely(!folio_test_pmd_mappable(folio))) { /* increment count (starts at -1) */ - atomic_set(&page->_mapcount, 0); + atomic_set(&folio->_mapcount, 0); nr = 1; } else { - VM_BUG_ON_PAGE(!PageTransHuge(page), page); /* increment count (starts at -1) */ - atomic_set(compound_mapcount_ptr(page), 0); - atomic_set(subpages_mapcount_ptr(page), COMPOUND_MAPPED); - nr = thp_nr_pages(page); - __mod_lruvec_page_state(page, NR_ANON_THPS, nr); + atomic_set(&folio->_entire_mapcount, 0); + atomic_set(&folio->_nr_pages_mapped, COMPOUND_MAPPED); + nr = folio_nr_pages(folio); + __lruvec_stat_mod_folio(folio, NR_ANON_THPS, nr); } - __mod_lruvec_page_state(page, NR_ANON_MAPPED, nr); - __page_set_anon_rmap(page, vma, address, 1); + __lruvec_stat_mod_folio(folio, NR_ANON_MAPPED, nr); + __page_set_anon_rmap(&folio->page, vma, address, 1); } /** -- 2.7.4