fsnotify: Use mnt_id when restoring mount mark

When there is a bind mount present on same mountpoint
where mark is laying the device of both mountpoints
is the same so we might end up getting wrong mountpoint.
Instead we should used mount id which is unique among
all mounpoints.

Note it's a fast fix, I need to review fsnotify code
more and make sure all corner cases are covered.

https://bugzilla.openvz.org/show_bug.cgi?id=2974

Reported-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Acked-by: Andrew Vagin <avagin@parallels.com>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
mm: mark VM_IO and VM_PFNMAP VMA-s as unsupported

vmsplice doesn't work for such VMA-s.

This flags is set in a kernel function remap_pfn_range()
(remap kernel memory to userspace), which is widely used by device
drivers to provide direct access to a device memory.

Reported-by: J F <jgmb45@gmail.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Acked-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>