net/vdev_netvsc: add automatic probing

Using DPDK in Hyper-V VM systems requires vdev_netvsc driver to pair
the NetVSC netdev device with the same MAC address PCI device by
fail-safe PMD.

Add vdev_netvsc custom scan in vdev bus to allow automatic probing in
Hyper-V VM systems unless it was already specified by command line.

Add "ignore" parameter to disable this auto-detection.

Signed-off-by: Matan Azrad <matan@mellanox.com>

diff --git a/doc/guides/nics/vdev_netvsc.rst b/doc/guides/nics/vdev_netvsc.rst
index 3c26990..55d130a 100644 (file)
--- a/doc/guides/nics/vdev_netvsc.rst
+++ b/doc/guides/nics/vdev_netvsc.rst
@@ -71,8 +71,8 @@ Build options
 Run-time parameters
 -------------------
 
-To invoke this driver, applications have to explicitly provide the
-``--vdev=net_vdev_netvsc`` EAL option.
+This driver is invoked automatically in Hyper-V VM systems unless the user
+invoked it by command line using ``--vdev=net_vdev_netvsc`` EAL option.
 
 The following device parameters are supported:
 
@@ -91,5 +91,10 @@ The following device parameters are supported:
   If nonzero, forces the use of specified interfaces even if not detected as
   NetVSC or detected as routed NETVSC.
 
+- ``ignore`` [int]
+
+  If nonzero, ignores the driver runnig (actually used to disable the
+  auto-detection in Hyper-V VM).
+
 Not specifying either ``iface`` or ``mac`` makes this driver attach itself to
 all unrouted NetVSC interfaces found on the system.

diff --git a/drivers/net/vdev_netvsc/vdev_netvsc.c b/drivers/net/vdev_netvsc/vdev_netvsc.c
index 2d03033..a8a1a7f 100644 (file)
--- a/drivers/net/vdev_netvsc/vdev_netvsc.c
+++ b/drivers/net/vdev_netvsc/vdev_netvsc.c
@@ -30,13 +30,16 @@
 #include <rte_errno.h>
 #include <rte_ethdev.h>
 #include <rte_ether.h>
+#include <rte_hypervisor.h>
 #include <rte_kvargs.h>
 #include <rte_log.h>
 
 #define VDEV_NETVSC_DRIVER net_vdev_netvsc
+#define VDEV_NETVSC_DRIVER_NAME RTE_STR(VDEV_NETVSC_DRIVER)
 #define VDEV_NETVSC_ARG_IFACE "iface"
 #define VDEV_NETVSC_ARG_MAC "mac"
 #define VDEV_NETVSC_ARG_FORCE "force"
+#define VDEV_NETVSC_ARG_IGNORE "ignore"
 #define VDEV_NETVSC_PROBE_MS 1000
 
 #define NETVSC_CLASS_ID "{f8615163-df3e-46c5-913f-f2d2f965ed0e}"
@@ -45,7 +48,7 @@
 #define DRV_LOG(level, ...) \
        rte_log(RTE_LOG_ ## level, \
                vdev_netvsc_logtype, \
-               RTE_FMT(RTE_STR(VDEV_NETVSC_DRIVER) ": " \
+               RTE_FMT(VDEV_NETVSC_DRIVER_NAME ": " \
                        RTE_FMT_HEAD(__VA_ARGS__,) "\n", \
                RTE_FMT_TAIL(__VA_ARGS__,)))
 
@@ -601,6 +604,7 @@ vdev_netvsc_vdev_probe(struct rte_vdev_device *dev)
                VDEV_NETVSC_ARG_IFACE,
                VDEV_NETVSC_ARG_MAC,
                VDEV_NETVSC_ARG_FORCE,
+               VDEV_NETVSC_ARG_IGNORE,
                NULL,
        };
        const char *name = rte_vdev_device_name(dev);
@@ -610,6 +614,7 @@ vdev_netvsc_vdev_probe(struct rte_vdev_device *dev)
        unsigned int specified = 0;
        unsigned int matched = 0;
        int force = 0;
+       int ignore = 0;
        unsigned int i;
        int ret;
 
@@ -623,10 +628,17 @@ vdev_netvsc_vdev_probe(struct rte_vdev_device *dev)
 
                if (!strcmp(pair->key, VDEV_NETVSC_ARG_FORCE))
                        force = !!atoi(pair->value);
+               else if (!strcmp(pair->key, VDEV_NETVSC_ARG_IGNORE))
+                       ignore = !!atoi(pair->value);
                else if (!strcmp(pair->key, VDEV_NETVSC_ARG_IFACE) ||
                         !strcmp(pair->key, VDEV_NETVSC_ARG_MAC))
                        ++specified;
        }
+       if (ignore) {
+               if (kvargs)
+                       rte_kvargs_free(kvargs);
+               return 0;
+       }
        rte_eal_alarm_cancel(vdev_netvsc_alarm, NULL);
        /* Gather interfaces. */
        ret = vdev_netvsc_foreach_iface(vdev_netvsc_netvsc_probe, name, kvargs,
@@ -690,7 +702,8 @@ RTE_PMD_REGISTER_ALIAS(VDEV_NETVSC_DRIVER, eth_vdev_netvsc);
 RTE_PMD_REGISTER_PARAM_STRING(net_vdev_netvsc,
                              VDEV_NETVSC_ARG_IFACE "=<string> "
                              VDEV_NETVSC_ARG_MAC "=<string> "
-                             VDEV_NETVSC_ARG_FORCE "=<int>");
+                             VDEV_NETVSC_ARG_FORCE "=<int> "
+                             VDEV_NETVSC_ARG_IGNORE "=<int>");
 
 /** Initialize driver log type. */
 RTE_INIT(vdev_netvsc_init_log)
@@ -699,3 +712,41 @@ RTE_INIT(vdev_netvsc_init_log)
        if (vdev_netvsc_logtype >= 0)
                rte_log_set_level(vdev_netvsc_logtype, RTE_LOG_NOTICE);
 }
+
+/** Compare function for vdev find device operation. */
+static int
+vdev_netvsc_cmp_rte_device(const struct rte_device *dev1,
+                          __rte_unused const void *_dev2)
+{
+       return strcmp(dev1->devargs->name, VDEV_NETVSC_DRIVER_NAME);
+}
+
+/**
+ * A callback called by vdev bus scan function to ensure this driver probing
+ * automatically in Hyper-V VM system unless it already exists in the
+ * devargs list.
+ */
+static void
+vdev_netvsc_scan_callback(__rte_unused void *arg)
+{
+       struct rte_vdev_device *dev;
+       struct rte_devargs *devargs;
+       struct rte_bus *vbus = rte_bus_find_by_name("vdev");
+
+       TAILQ_FOREACH(devargs, &devargs_list, next)
+               if (!strcmp(devargs->name, VDEV_NETVSC_DRIVER_NAME))
+                       return;
+       dev = (struct rte_vdev_device *)vbus->find_device(NULL,
+               vdev_netvsc_cmp_rte_device, VDEV_NETVSC_DRIVER_NAME);
+       if (dev)
+               return;
+       if (rte_eal_devargs_add(RTE_DEVTYPE_VIRTUAL, VDEV_NETVSC_DRIVER_NAME))
+               DRV_LOG(ERR, "unable to add netvsc devargs.");
+}
+
+/** Initialize the custom scan. */
+RTE_INIT(vdev_netvsc_custom_scan_add)
+{
+       if (rte_hypervisor_get() == RTE_HYPERVISOR_HYPERV)
+               rte_vdev_add_custom_scan(vdev_netvsc_scan_callback, NULL);
+}