[dpdk-dev] [PATCH 2/2] virtio: support IOMMU platform

[Jason Wang <jasowang@redhat.com>]

Virtio pmd doesn't support VFIO in the past since devices bypass IOMMU
completely. But recently, the work of making virtio device work with
IOMMU is near to complete. So this patch make pmd support IOMMU by:

- Allow VFIO mapping by setting RTE_PCI_DRV_NEED_MAPPING flag
- Negotiate feature VIRTIO_F_IOMMU_PLATFORM

Signed-off-by: Jason Wang <jasowang@redhat.com>
---
 drivers/net/virtio/virtio_ethdev.c | 2 +-
 drivers/net/virtio/virtio_ethdev.h | 3 ++-
 drivers/net/virtio/virtio_pci.h    | 3 ++-
 3 files changed, 5 insertions(+), 3 deletions(-)

diff --git a/drivers/net/virtio/virtio_ethdev.c b/drivers/net/virtio/virtio_ethdev.c
index f48e037..0d6d4d2 100644
--- a/drivers/net/virtio/virtio_ethdev.c
+++ b/drivers/net/virtio/virtio_ethdev.c
@@ -1307,7 +1307,7 @@ static struct eth_driver rte_virtio_pmd = {
 	.pci_drv = {
 		.name = "rte_virtio_pmd",
 		.id_table = pci_id_virtio_map,
-		.drv_flags = RTE_PCI_DRV_DETACHABLE,
+		.drv_flags = RTE_PCI_DRV_DETACHABLE | RTE_PCI_DRV_NEED_MAPPING,
 	},
 	.eth_dev_init = eth_virtio_dev_init,
 	.eth_dev_uninit = eth_virtio_dev_uninit,
diff --git a/drivers/net/virtio/virtio_ethdev.h b/drivers/net/virtio/virtio_ethdev.h
index 2ecec6e..04a06e2 100644
--- a/drivers/net/virtio/virtio_ethdev.h
+++ b/drivers/net/virtio/virtio_ethdev.h
@@ -63,7 +63,8 @@
 	 1u << VIRTIO_NET_F_CTRL_RX	  |	\
 	 1u << VIRTIO_NET_F_CTRL_VLAN	  |	\
 	 1u << VIRTIO_NET_F_MRG_RXBUF	  |	\
-	 1ULL << VIRTIO_F_VERSION_1)
+	 1ULL << VIRTIO_F_VERSION_1       |	\
+	 1ULL << VIRTIO_F_IOMMU_PLATFORM )
 
 /*
  * CQ function prototype
diff --git a/drivers/net/virtio/virtio_pci.h b/drivers/net/virtio/virtio_pci.h
index d3bdfa0..dd74c0f 100644
--- a/drivers/net/virtio/virtio_pci.h
+++ b/drivers/net/virtio/virtio_pci.h
@@ -139,6 +139,7 @@ struct virtnet_ctl;
 #define VIRTIO_RING_F_INDIRECT_DESC	28
 
 #define VIRTIO_F_VERSION_1		32
+#define VIRTIO_F_IOMMU_PLATFORM	33
 
 /*
  * Some VirtIO feature bits (currently bits 28 through 31) are
@@ -146,7 +147,7 @@ struct virtnet_ctl;
  * rest are per-device feature bits.
  */
 #define VIRTIO_TRANSPORT_F_START 28
-#define VIRTIO_TRANSPORT_F_END   32
+#define VIRTIO_TRANSPORT_F_END   34
 
 /* The Guest publishes the used index for which it expects an interrupt
  * at the end of the avail ring. Host should ignore the avail->flags field. */
-- 
2.7.4