diff options
| author | Peter Xu <peterx@redhat.com> | 2022-05-13 05:22:56 +0200 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2022-05-13 16:20:11 +0200 |
| commit | b1f9e876862d8f7176299ec4fb2108bc1045cbc8 (patch) | |
| tree | 9a2de240e607dd786011ec3a2108962d4f444782 /fs/userfaultfd.c | |
| parent | mm/pagemap: recognize uffd-wp bit for shmem/hugetlbfs (diff) | |
| download | linux-b1f9e876862d8f7176299ec4fb2108bc1045cbc8.tar.xz linux-b1f9e876862d8f7176299ec4fb2108bc1045cbc8.zip | |
mm/uffd: enable write protection for shmem & hugetlbfs
We've had all the necessary changes ready for both shmem and hugetlbfs.
Turn on all the shmem/hugetlbfs switches for userfaultfd-wp.
We can expand UFFD_API_RANGE_IOCTLS_BASIC with _UFFDIO_WRITEPROTECT too
because all existing types now support write protection mode.
Since vma_can_userfault() will be used elsewhere, move into userfaultfd_k.h.
Link: https://lkml.kernel.org/r/20220405014926.15101-1-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
Cc: Alistair Popple <apopple@nvidia.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: "Kirill A . Shutemov" <kirill@shutemov.name>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Nadav Amit <nadav.amit@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'fs/userfaultfd.c')
| -rw-r--r-- | fs/userfaultfd.c | 21 |
1 files changed, 3 insertions, 18 deletions
diff --git a/fs/userfaultfd.c b/fs/userfaultfd.c index 78b68e0f9774..e943370107d0 100644 --- a/fs/userfaultfd.c +++ b/fs/userfaultfd.c @@ -1258,24 +1258,6 @@ static __always_inline int validate_range(struct mm_struct *mm, return 0; } -static inline bool vma_can_userfault(struct vm_area_struct *vma, - unsigned long vm_flags) -{ - /* FIXME: add WP support to hugetlbfs and shmem */ - if (vm_flags & VM_UFFD_WP) { - if (is_vm_hugetlb_page(vma) || vma_is_shmem(vma)) - return false; - } - - if (vm_flags & VM_UFFD_MINOR) { - if (!(is_vm_hugetlb_page(vma) || vma_is_shmem(vma))) - return false; - } - - return vma_is_anonymous(vma) || is_vm_hugetlb_page(vma) || - vma_is_shmem(vma); -} - static int userfaultfd_register(struct userfaultfd_ctx *ctx, unsigned long arg) { @@ -1957,6 +1939,9 @@ static int userfaultfd_api(struct userfaultfd_ctx *ctx, #ifndef CONFIG_HAVE_ARCH_USERFAULTFD_WP uffdio_api.features &= ~UFFD_FEATURE_PAGEFAULT_FLAG_WP; #endif +#ifndef CONFIG_PTE_MARKER_UFFD_WP + uffdio_api.features &= ~UFFD_FEATURE_WP_HUGETLBFS_SHMEM; +#endif uffdio_api.ioctls = UFFD_API_IOCTLS; ret = -EFAULT; if (copy_to_user(buf, &uffdio_api, sizeof(uffdio_api))) |