The patch titled
Subject: userfaultfd: wp: userfaultfd_pte/huge_pmd_wp() helpers
has been added to the -mm tree. Its filename is
userfaultfd-wp-userfaultfd_pte-huge_pmd_wp-helpers.patch
This patch should soon appear at
http://ozlabs.org/~akpm/mmots/broken-out/userfaultfd-wp-userfaultfd_pte-huge_pmd_wp-helpers.patch
and later at
http://ozlabs.org/~akpm/mmotm/broken-out/userfaultfd-wp-userfaultfd_pte-huge_pmd_wp-helpers.patch
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------------------------------------------------------
From: Andrea Arcangeli <aarcange@xxxxxxxxxx>
Subject: userfaultfd: wp: userfaultfd_pte/huge_pmd_wp() helpers
Implement helpers methods to invoke userfaultfd wp faults more
selectively: not only when a wp fault triggers on a vma with vma->vm_flags
VM_UFFD_WP set, but only if the _PAGE_UFFD_WP bit is set in the pagetable
too.
Link: http://lkml.kernel.org/r/20200220163112.11409-5-peterx@xxxxxxxxxx
Signed-off-by: Andrea Arcangeli <aarcange@xxxxxxxxxx>
Signed-off-by: Peter Xu <peterx@xxxxxxxxxx>
Reviewed-by: Jerome Glisse <jglisse@xxxxxxxxxx>
Reviewed-by: Mike Rapoport <rppt@xxxxxxxxxxxxxxxxxx>
Cc: Bobby Powers <bobbypowers@xxxxxxxxx>
Cc: Brian Geffon <bgeffon@xxxxxxxxxx>
Cc: David Hildenbrand <david@xxxxxxxxxx>
Cc: Denis Plotnikov <dplotnikov@xxxxxxxxxxxxx>
Cc: "Dr . David Alan Gilbert" <dgilbert@xxxxxxxxxx>
Cc: Hugh Dickins <hughd@xxxxxxxxxx>
Cc: Johannes Weiner <hannes@xxxxxxxxxxx>
Cc: "Kirill A . Shutemov" <kirill@xxxxxxxxxxxxx>
Cc: Martin Cracauer <cracauer@xxxxxxxx>
Cc: Marty McFadden <mcfadden8@xxxxxxxx>
Cc: Maya Gokhale <gokhale2@xxxxxxxx>
Cc: Mel Gorman <mgorman@xxxxxxx>
Cc: Mike Kravetz <mike.kravetz@xxxxxxxxxx>
Cc: Pavel Emelyanov <xemul@xxxxxxxxxxxxx>
Cc: Pavel Emelyanov <xemul@xxxxxxxxxxxxx>
Cc: Rik van Riel <riel@xxxxxxxxxx>
Cc: Shaohua Li <shli@xxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
include/linux/userfaultfd_k.h | 27 +++++++++++++++++++++++++++
1 file changed, 27 insertions(+)
--- a/include/linux/userfaultfd_k.h~userfaultfd-wp-userfaultfd_pte-huge_pmd_wp-helpers
+++ a/include/linux/userfaultfd_k.h
@@ -14,6 +14,8 @@
#include <linux/userfaultfd.h> /* linux/include/uapi/linux/userfaultfd.h */
#include <linux/fcntl.h>
+#include <linux/mm.h>
+#include <asm-generic/pgtable_uffd.h>
/*
* CAREFUL: Check include/uapi/asm-generic/fcntl.h when defining
@@ -57,6 +59,18 @@ static inline bool userfaultfd_wp(struct
return vma->vm_flags & VM_UFFD_WP;
}
+static inline bool userfaultfd_pte_wp(struct vm_area_struct *vma,
+ pte_t pte)
+{
+ return userfaultfd_wp(vma) && pte_uffd_wp(pte);
+}
+
+static inline bool userfaultfd_huge_pmd_wp(struct vm_area_struct *vma,
+ pmd_t pmd)
+{
+ return userfaultfd_wp(vma) && pmd_uffd_wp(pmd);
+}
+
static inline bool userfaultfd_armed(struct vm_area_struct *vma)
{
return vma->vm_flags & (VM_UFFD_MISSING | VM_UFFD_WP);
@@ -106,6 +120,19 @@ static inline bool userfaultfd_wp(struct
return false;
}
+static inline bool userfaultfd_pte_wp(struct vm_area_struct *vma,
+ pte_t pte)
+{
+ return false;
+}
+
+static inline bool userfaultfd_huge_pmd_wp(struct vm_area_struct *vma,
+ pmd_t pmd)
+{
+ return false;
+}
+
+
static inline bool userfaultfd_armed(struct vm_area_struct *vma)
{
return false;
_
Patches currently in -mm which might be from aarcange@xxxxxxxxxx are
userfaultfd-wp-hook-userfault-handler-to-write-protection-fault.patch
userfaultfd-wp-add-wp-pagetable-tracking-to-x86.patch
userfaultfd-wp-userfaultfd_pte-huge_pmd_wp-helpers.patch
userfaultfd-wp-add-uffdio_copy_mode_wp.patch
userfaultfd-wp-add-the-writeprotect-api-to-userfaultfd-ioctl.patch
