.. _Hyper-V: https://docs.microsoft.com/en-us/windows-hardware/drivers/network/overview-of-hyper-v
+Implementation details
+----------------------
+
+Each instance of this driver effectively needs to drive two devices: the
+NetVSC interface proper and its SR-IOV VF (referred to as "physical" from
+this point on) counterpart sharing the same MAC address.
+
+Physical devices are part of the host system and cannot be maintained during
+VM migration. From a VM standpoint they appear as hot-plug devices that come
+and go without prior notice.
+
+When the physical device is present, egress and most of the ingress traffic
+flows through it; only multicasts and other hypervisor control still flow
+through NetVSC. Otherwise, NetVSC acts as a fallback for all traffic.
+
+To avoid unnecessary code duplication and ensure maximum performance,
+handling of physical devices is left to their original PMDs; this virtual
+device driver (also known as *vdev*) manages other PMDs as summarized by the
+following block diagram::
+
+ .------------------.
+ | DPDK application |
+ `--------+---------'
+ |
+ .------+------.
+ | DPDK ethdev |
+ `------+------' Control
+ | |
+ .------------+------------. v .--------------------.
+ | failsafe PMD +---------+ vdev_netvsc driver |
+ `--+-------------------+--' `--------------------'
+ | |
+ | .........|.........
+ | : | :
+ .----+----. : .----+----. :
+ | tap PMD | : | any PMD | :
+ `----+----' : `----+----' : <-- Hot-pluggable
+ | : | :
+ .------+-------. : .-----+-----. :
+ | NetVSC-based | : | SR-IOV VF | :
+ | netdevice | : | device | :
+ `--------------' : `-----------' :
+ :.................:
+
+
+This driver implementation may be temporary and should be improved or removed
+either when hot-plug will be fully supported in EAL and bus drivers or when
+a new NetVSC driver will be integrated.
+
Build options
-------------
- ``CONFIG_RTE_LIBRTE_VDEV_NETVSC_PMD`` (default ``y``)
Toggle compilation of this driver.
+
+Run-time parameters
+-------------------
+
+To invoke this driver, applications have to explicitly provide the
+``--vdev=net_vdev_netvsc`` EAL option.
+
+The following device parameters are supported:
+
+- ``iface`` [string]
+
+ Provide a specific NetVSC interface (netdevice) name to attach this driver
+ to. Can be provided multiple times for additional instances.
+
+- ``mac`` [string]
+
+ Same as ``iface`` except a suitable NetVSC interface is located using its
+ MAC address.
+
+Not specifying either ``iface`` or ``mac`` makes this driver attach itself to
+all NetVSC interfaces found on the system.
git.droids-corp.org / dpdk.git / blobdiff