virtio: virtio: implement packed queues from virtio 1.1

Type: feature

Change-Id: I12703371541298efa029903d6762b1cd1f7322ca
Signed-off-by: Mohsin Kazmi <sykazmi@cisco.com>

1 files changed, 20 insertions, 5 deletions

diff --git a/src/vnet/devices/virtio/virtio_pci_modern.c b/src/vnet/devices/virtio/virtio_pci_modern.c
index 1934f98003d..8e090ffed3a 100644
--- a/src/vnet/devices/virtio/virtio_pci_modern.c
+++ b/src/vnet/devices/virtio/virtio_pci_modern.c
@@ -268,24 +268,39 @@ static u8
 virtio_pci_modern_setup_queue (vlib_main_t * vm, virtio_if_t * vif,
 			       u16 queue_id, void *p)
 {
-  vring_t vr;
+  u64 desc, avail, used;
   u16 queue_size = 0;
 
   virtio_pci_modern_set_queue_select (vif, queue_id);
   queue_size = virtio_pci_modern_get_queue_size (vm, vif, queue_id);
-  vring_init (&vr, queue_size, p, VIRTIO_PCI_VRING_ALIGN);
 
-  u64 desc = vlib_physmem_get_pa (vm, vr.desc);
+  if (vif->is_packed)
+    {
+      virtio_vring_t *vring = (virtio_vring_t *) p;
+
+      desc = vlib_physmem_get_pa (vm, vring->packed_desc);
+      avail = vlib_physmem_get_pa (vm, vring->driver_event);
+      used = vlib_physmem_get_pa (vm, vring->device_event);
+    }
+  else
+    {
+      vring_t vr;
+
+      vring_init (&vr, queue_size, p, VIRTIO_PCI_VRING_ALIGN);
+
+      desc = vlib_physmem_get_pa (vm, vr.desc);
+      avail = vlib_physmem_get_pa (vm, vr.avail);
+      used = vlib_physmem_get_pa (vm, vr.used);
+    }
+
   virtio_pci_modern_set_queue_desc (vif, desc);
   if (desc != virtio_pci_modern_get_queue_desc (vif))
     return 1;
 
-  u64 avail = vlib_physmem_get_pa (vm, vr.avail);
   virtio_pci_modern_set_queue_driver (vif, avail);
   if (avail != virtio_pci_modern_get_queue_driver (vif))
     return 1;
 
-  u64 used = vlib_physmem_get_pa (vm, vr.used);
   virtio_pci_modern_set_queue_device (vif, used);
   if (used != virtio_pci_modern_get_queue_device (vif))
     return 1;