From 72981e0e7b609c741d7764cc920c8fec00920bd5 Mon Sep 17 00:00:00 2001 From: Andrea Arcangeli Date: Mon, 6 Apr 2020 20:05:41 -0700 Subject: userfaultfd: wp: add UFFDIO_COPY_MODE_WP This allows UFFDIO_COPY to map pages write-protected. [peterx@redhat.com: switch to VM_WARN_ON_ONCE in mfill_atomic_pte; add brackets around "dst_vma->vm_flags & VM_WRITE"; fix wordings in comments and commit messages] Signed-off-by: Andrea Arcangeli Signed-off-by: Peter Xu Signed-off-by: Andrew Morton Reviewed-by: Jerome Glisse Reviewed-by: Mike Rapoport Cc: Bobby Powers Cc: Brian Geffon Cc: David Hildenbrand Cc: Denis Plotnikov Cc: "Dr . David Alan Gilbert" Cc: Hugh Dickins Cc: Johannes Weiner Cc: "Kirill A . Shutemov" Cc: Martin Cracauer Cc: Marty McFadden Cc: Maya Gokhale Cc: Mel Gorman Cc: Mike Kravetz Cc: Pavel Emelyanov Cc: Rik van Riel Cc: Shaohua Li Link: http://lkml.kernel.org/r/20200220163112.11409-6-peterx@redhat.com Signed-off-by: Linus Torvalds --- include/linux/userfaultfd_k.h | 2 +- include/uapi/linux/userfaultfd.h | 11 ++++++----- 2 files changed, 7 insertions(+), 6 deletions(-) (limited to 'include') diff --git a/include/linux/userfaultfd_k.h b/include/linux/userfaultfd_k.h index 7b91b76aac58..dcd33172b728 100644 --- a/include/linux/userfaultfd_k.h +++ b/include/linux/userfaultfd_k.h @@ -36,7 +36,7 @@ extern vm_fault_t handle_userfault(struct vm_fault *vmf, unsigned long reason); extern ssize_t mcopy_atomic(struct mm_struct *dst_mm, unsigned long dst_start, unsigned long src_start, unsigned long len, - bool *mmap_changing); + bool *mmap_changing, __u64 mode); extern ssize_t mfill_zeropage(struct mm_struct *dst_mm, unsigned long dst_start, unsigned long len, diff --git a/include/uapi/linux/userfaultfd.h b/include/uapi/linux/userfaultfd.h index 48f1a7c2f1f0..340f23bc251d 100644 --- a/include/uapi/linux/userfaultfd.h +++ b/include/uapi/linux/userfaultfd.h @@ -203,13 +203,14 @@ struct uffdio_copy { __u64 dst; __u64 src; __u64 len; +#define UFFDIO_COPY_MODE_DONTWAKE ((__u64)1<<0) /* - * There will be a wrprotection flag later that allows to map - * pages wrprotected on the fly. And such a flag will be - * available if the wrprotection ioctl are implemented for the - * range according to the uffdio_register.ioctls. + * UFFDIO_COPY_MODE_WP will map the page write protected on + * the fly. UFFDIO_COPY_MODE_WP is available only if the + * write protected ioctl is implemented for the range + * according to the uffdio_register.ioctls. */ -#define UFFDIO_COPY_MODE_DONTWAKE ((__u64)1<<0) +#define UFFDIO_COPY_MODE_WP ((__u64)1<<1) __u64 mode; /* -- cgit v1.2.3