[PATCH v4 06/27] userfaultfd: wp: add helper for writeprotect check

From: Peter Xu
Date: Fri Apr 26 2019 - 00:53:01 EST


From: Shaohua Li <shli@xxxxxx>

add helper for writeprotect check. Will use it later.

Cc: Andrea Arcangeli <aarcange@xxxxxxxxxx>
Cc: Pavel Emelyanov <xemul@xxxxxxxxxxxxx>
Cc: Rik van Riel <riel@xxxxxxxxxx>
Cc: Kirill A. Shutemov <kirill@xxxxxxxxxxxxx>
Cc: Mel Gorman <mgorman@xxxxxxx>
Cc: Hugh Dickins <hughd@xxxxxxxxxx>
Cc: Johannes Weiner <hannes@xxxxxxxxxxx>
Signed-off-by: Shaohua Li <shli@xxxxxx>
Signed-off-by: Andrea Arcangeli <aarcange@xxxxxxxxxx>
Reviewed-by: Jerome Glisse <jglisse@xxxxxxxxxx>
Reviewed-by: Mike Rapoport <rppt@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Peter Xu <peterx@xxxxxxxxxx>
---
include/linux/userfaultfd_k.h | 10 ++++++++++
1 file changed, 10 insertions(+)

diff --git a/include/linux/userfaultfd_k.h b/include/linux/userfaultfd_k.h
index 37c9eba75c98..38f748e7186e 100644
--- a/include/linux/userfaultfd_k.h
+++ b/include/linux/userfaultfd_k.h
@@ -50,6 +50,11 @@ static inline bool userfaultfd_missing(struct vm_area_struct *vma)
return vma->vm_flags & VM_UFFD_MISSING;
}

+static inline bool userfaultfd_wp(struct vm_area_struct *vma)
+{
+ return vma->vm_flags & VM_UFFD_WP;
+}
+
static inline bool userfaultfd_armed(struct vm_area_struct *vma)
{
return vma->vm_flags & (VM_UFFD_MISSING | VM_UFFD_WP);
@@ -94,6 +99,11 @@ static inline bool userfaultfd_missing(struct vm_area_struct *vma)
return false;
}

+static inline bool userfaultfd_wp(struct vm_area_struct *vma)
+{
+ return false;
+}
+
static inline bool userfaultfd_armed(struct vm_area_struct *vma)
{
return false;
--
2.17.1