userfaultfd: non-cooperative: add event for exit() notification
Allow userfaultfd monitor track termination of the processes that have
memory backed by the uffd.
[rppt@linux.vnet.ibm.com: add comment]
Link: http://lkml.kernel.org/r/20170202135448.GB19804@rapoport-lnxLink: http://lkml.kernel.org/r/1485542673-24387-4-git-send-email-rppt@linux.vnet.ibm.com
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Acked-by: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Pavel Emelyanov <xemul@virtuozzo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/include/linux/userfaultfd_k.h b/include/linux/userfaultfd_k.h
index a40be5d..0468548 100644
--- a/include/linux/userfaultfd_k.h
+++ b/include/linux/userfaultfd_k.h
@@ -72,6 +72,8 @@ extern int userfaultfd_unmap_prep(struct vm_area_struct *vma,
extern void userfaultfd_unmap_complete(struct mm_struct *mm,
struct list_head *uf);
+extern void userfaultfd_exit(struct mm_struct *mm);
+
#else /* CONFIG_USERFAULTFD */
/* mm helpers */
@@ -136,6 +138,11 @@ static inline void userfaultfd_unmap_complete(struct mm_struct *mm,
struct list_head *uf)
{
}
+
+static inline void userfaultfd_exit(struct mm_struct *mm)
+{
+}
+
#endif /* CONFIG_USERFAULTFD */
#endif /* _LINUX_USERFAULTFD_K_H */