virtio-mem: Add parent resource for all added "System RAM"
Let's add a parent resource, named after the virtio device (inspired by
drivers/dax/kmem.c). This allows user space to identify which memory
belongs to which virtio-mem device.
With this change and two virtio-mem devices:
:/# cat /proc/iomem
00000000-
00000fff : Reserved
00001000-
0009fbff : System RAM
[...]
140000000-
333ffffff : virtio0
140000000-
147ffffff : System RAM
148000000-
14fffffff : System RAM
150000000-
157ffffff : System RAM
[...]
334000000-
3033ffffff : virtio1
338000000-
33fffffff : System RAM
340000000-
347ffffff : System RAM
348000000-
34fffffff : System RAM
[...]
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20200507140139.17083-12-david@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com>