From 887b22c628c615811be3b877e02c9c1fe9d85d6d Mon Sep 17 00:00:00 2001 From: "Matthew Wilcox (Oracle)" Date: Thu, 15 Oct 2020 20:05:23 -0700 Subject: [PATCH] mm/filemap: fix page cache removal for arbitrary sized THPs Patch series "Remove assumptions of THP size". There are a number of places in the VM which assume that a THP is a PMD in size. That's true today, and remains true after this patch series, but this is a prerequisite for switching to arbitrary-sized THPs. thp_nr_pages() still returns either HPAGE_PMD_NR or 1, but will be changed later. This patch (of 11): page_cache_free_page() assumes THPs are PMD_SIZE; fix that assumption. Signed-off-by: Matthew Wilcox (Oracle) Signed-off-by: Andrew Morton Acked-by: Kirill A. Shutemov Cc: Huang Ying Link: https://lkml.kernel.org/r/20200908195539.25896-1-willy@infradead.org Link: https://lkml.kernel.org/r/20200908195539.25896-2-willy@infradead.org Signed-off-by: Linus Torvalds --- mm/filemap.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/mm/filemap.c b/mm/filemap.c index 3b76d79fd0cf..2937b57329be 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -249,7 +249,7 @@ static void page_cache_free_page(struct address_space *mapping, freepage(page); if (PageTransHuge(page) && !PageHuge(page)) { - page_ref_sub(page, HPAGE_PMD_NR); + page_ref_sub(page, thp_nr_pages(page)); VM_BUG_ON_PAGE(page_count(page) <= 0, page); } else { put_page(page);