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author | Matthew Wilcox (Oracle) <willy@infradead.org> | 2023-01-11 14:28:54 +0000 |
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committer | Andrew Morton <akpm@linux-foundation.org> | 2023-02-02 22:32:56 -0800 |
commit | 4d510f3da4c216d4c2695395f67aec38e2aa6cc7 (patch) | |
tree | e726b8fb8ac10a96c739baa733f526fd5c083e5b /mm/rmap.c | |
parent | eb01a2ad7e9cba1b9dd131edc5a26ffbda90a5ed (diff) | |
download | lwn-4d510f3da4c216d4c2695395f67aec38e2aa6cc7.tar.gz lwn-4d510f3da4c216d4c2695395f67aec38e2aa6cc7.zip |
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) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'mm/rmap.c')
-rw-r--r-- | mm/rmap.c | 37 |
1 files changed, 18 insertions, 19 deletions
diff --git a/mm/rmap.c b/mm/rmap.c index 430c066c2295..513e23e5a158 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); } /** |