[PATCH v3 25/27] mm/pagemap: Recognize uffd-wp bit for shmem/hugetlbfs
From: Peter Xu <peterx@redhat.com>
Date: 2021-05-27 20:24:33
Also in:
lkml
Subsystem:
filesystems (vfs and infrastructure), memory mapping, proc filesystem, the rest · Maintainers:
Alexander Viro, Christian Brauner, Andrew Morton, Liam R. Howlett, Lorenzo Stoakes, Linus Torvalds
This requires the pagemap code to be able to recognize the newly introduced swap special pte for uffd-wp, meanwhile the general case for hugetlb that we recently start to support. It should make pagemap uffd-wp support complete. Signed-off-by: Peter Xu <peterx@redhat.com> --- fs/proc/task_mmu.c | 7 +++++++ 1 file changed, 7 insertions(+)
diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c
index 9c5af77b5290..988e29fa1f00 100644
--- a/fs/proc/task_mmu.c
+++ b/fs/proc/task_mmu.c@@ -1389,6 +1389,8 @@ static pagemap_entry_t pte_to_pagemap_entry(struct pagemapread *pm, flags |= PM_SWAP; if (is_pfn_swap_entry(entry)) page = pfn_swap_entry_to_page(entry); + } else if (pte_swp_uffd_wp_special(pte)) { + flags |= PM_UFFD_WP; } if (page && !PageAnon(page))
@@ -1522,10 +1524,15 @@ static int pagemap_hugetlb_range(pte_t *ptep, unsigned long hmask, if (page_mapcount(page) == 1) flags |= PM_MMAP_EXCLUSIVE; + if (huge_pte_uffd_wp(pte)) + flags |= PM_UFFD_WP; + flags |= PM_PRESENT; if (pm->show_pfn) frame = pte_pfn(pte) + ((addr & ~hmask) >> PAGE_SHIFT); + } else if (pte_swp_uffd_wp_special(pte)) { + flags |= PM_UFFD_WP; } for (; addr != end; addr += PAGE_SIZE) {
--
2.31.1