userfaultfd: use vma_is_anonymous

Cleanup the vma->vm_ops usage.

Side note: it would be more robust if vma_is_anonymous() would also
check that vm_flags hasn't VM_PFNMAP set.

Link: http://lkml.kernel.org/r/20161216144821.5183-5-aarcange@redhat.com
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Cc: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Cc: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: Michael Rapoport <RAPOPORT@il.ibm.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/fs/userfaultfd.c b/fs/userfaultfd.c
index 71e917387ec386866c19d5a31db9bef0b8100b9c..7e8f0d60718d882c696c87359a368205de19f16b 100644 (file)
--- a/fs/userfaultfd.c
+++ b/fs/userfaultfd.c
@@ -830,7 +830,7 @@ static int userfaultfd_register(struct userfaultfd_ctx *ctx,
 
                /* check not compatible vmas */
                ret = -EINVAL;
-               if (cur->vm_ops)
+               if (!vma_is_anonymous(cur))
                        goto out_unlock;
 
                /*
@@ -855,7 +855,7 @@ static int userfaultfd_register(struct userfaultfd_ctx *ctx,
        do {
                cond_resched();
 
-               BUG_ON(vma->vm_ops);
+               BUG_ON(!vma_is_anonymous(vma));
                BUG_ON(vma->vm_userfaultfd_ctx.ctx &&
                       vma->vm_userfaultfd_ctx.ctx != ctx);
 
@@ -981,7 +981,7 @@ static int userfaultfd_unregister(struct userfaultfd_ctx *ctx,
                 * provides for more strict behavior to notice
                 * unregistration errors.
                 */
-               if (cur->vm_ops)
+               if (!vma_is_anonymous(cur))
                        goto out_unlock;
 
                found = true;
@@ -995,7 +995,7 @@ static int userfaultfd_unregister(struct userfaultfd_ctx *ctx,
        do {
                cond_resched();
 
-               BUG_ON(vma->vm_ops);
+               BUG_ON(!vma_is_anonymous(vma));
 
                /*
                 * Nothing to do: this vma is already registered into this

diff --git a/mm/userfaultfd.c b/mm/userfaultfd.c
index af817e5060fbfbda2be8ba35024c1ad460055b20..9c2ed70ac78de0bc2189ccbb25c509f141e885a7 100644 (file)
--- a/mm/userfaultfd.c
+++ b/mm/userfaultfd.c
@@ -197,7 +197,7 @@ retry:
         * FIXME: only allow copying on anonymous vmas, tmpfs should
         * be added.
         */
-       if (dst_vma->vm_ops)
+       if (!vma_is_anonymous(dst_vma))
                goto out_unlock;
 
        /*