[dpdk-dev] [PATCH v3 4/4] virtio: check if kernel driver is manipulating the virtio device

[Huawei Xie <huawei.xie@intel.com>]

v3 changes:
 change log message to tell user that the virtio device is skipped
due to it is managed by kernel driver, instead of asking user to
unbind it from kernel driver.

v2 changes:
 change LOG level from ERR to INFO

virtio PMD could use IO port to configure the virtio device without
using uio driver(vfio-noniommu mode should work as well).

There are two issues with previous implementation:
1) virtio PMD will take over each virtio device blindly even if some
are not intended for DPDK.
2) driver conflict between virtio PMD and virtio-net kernel driver.

This patch checks if there is any kernel driver manipulating the virtio
device before virtio PMD uses IO port to configure the device.

Fixes: da978dfdc43b ("virtio: use port IO to get PCI resource")

Signed-off-by: Huawei Xie <huawei.xie@intel.com>
---
 drivers/net/virtio/virtio_ethdev.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/net/virtio/virtio_ethdev.c b/drivers/net/virtio/virtio_ethdev.c
index e815acd..ea1874a 100644
--- a/drivers/net/virtio/virtio_ethdev.c
+++ b/drivers/net/virtio/virtio_ethdev.c
@@ -1138,6 +1138,11 @@ static int virtio_resource_init_by_ioports(struct rte_pci_device *pci_dev)
 	int found = 0;
 	size_t linesz;
 
+	if (pci_dev->kdrv != RTE_KDRV_NONE) {
+		PMD_INIT_LOG(INFO, "skip kernel managed virtio device.");
+		return -1;
+	}
+
 	snprintf(pci_id, sizeof(pci_id), PCI_PRI_FMT,
 		 pci_dev->addr.domain,
 		 pci_dev->addr.bus,
-- 
1.8.1.4