From 906d278d75e364f2bb85dc1e1ff6265ea46e7e43 Mon Sep 17 00:00:00 2001 From: William Kucharski Date: Fri, 18 Oct 2019 20:20:33 -0700 Subject: [PATCH] mm/vmscan.c: support removing arbitrary sized pages from mapping __remove_mapping() assumes that pages can only be either base pages or HPAGE_PMD_SIZE. Ask the page what size it is. Link: http://lkml.kernel.org/r/20191017164223.2762148-4-songliubraving@fb.com Fixes: 99cb0dbd47a1 ("mm,thp: add read-only THP support for (non-shmem) FS") Signed-off-by: William Kucharski Signed-off-by: Matthew Wilcox (Oracle) Signed-off-by: Song Liu Acked-by: Yang Shi Cc: "Kirill A. Shutemov" Cc: Oleg Nesterov Cc: Srikar Dronamraju Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/vmscan.c | 5 +---- 1 file changed, 1 insertion(+), 4 deletions(-) diff --git a/mm/vmscan.c b/mm/vmscan.c index 024b7e9..ee4eecc 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -933,10 +933,7 @@ static int __remove_mapping(struct address_space *mapping, struct page *page, * Note that if SetPageDirty is always performed via set_page_dirty, * and thus under the i_pages lock, then this ordering is not required. */ - if (unlikely(PageTransHuge(page)) && PageSwapCache(page)) - refcount = 1 + HPAGE_PMD_NR; - else - refcount = 2; + refcount = 1 + compound_nr(page); if (!page_ref_freeze(page, refcount)) goto cannot_free; /* note: atomic_cmpxchg in page_ref_freeze provides the smp_rmb */ -- 2.7.4