From 5c041f5d1f23d3a172dd0db3215634c484b4acd6 Mon Sep 17 00:00:00 2001 From: Peter Xu Date: Thu, 12 May 2022 20:22:52 -0700 Subject: mm: teach core mm about pte markers This patch still does not use pte marker in any way, however it teaches the core mm about the pte marker idea. For example, handle_pte_marker() is introduced that will parse and handle all the pte marker faults. Many of the places are more about commenting it up - so that we know there's the possibility of pte marker showing up, and why we don't need special code for the cases. [peterx@redhat.com: userfaultfd.c needs swapops.h] Link: https://lkml.kernel.org/r/YmRlVj3cdizYJsr0@xz-m1.local Link: https://lkml.kernel.org/r/20220405014833.14015-1-peterx@redhat.com Signed-off-by: Peter Xu Cc: Alistair Popple Cc: Andrea Arcangeli Cc: Axel Rasmussen Cc: David Hildenbrand Cc: Hugh Dickins Cc: Jerome Glisse Cc: "Kirill A . Shutemov" Cc: Matthew Wilcox Cc: Mike Kravetz Cc: Mike Rapoport Cc: Nadav Amit Signed-off-by: Andrew Morton --- mm/mincore.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'mm/mincore.c') diff --git a/mm/mincore.c b/mm/mincore.c index f4f627325e12..fa200c14185f 100644 --- a/mm/mincore.c +++ b/mm/mincore.c @@ -122,7 +122,8 @@ static int mincore_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end, for (; addr != end; ptep++, addr += PAGE_SIZE) { pte_t pte = *ptep; - if (pte_none(pte)) + /* We need to do cache lookup too for pte markers */ + if (pte_none_mostly(pte)) __mincore_unmapped_range(addr, addr + PAGE_SIZE, vma, vec); else if (pte_present(pte)) -- cgit v1.2.3-58-ga151