--- /dev/null
+.. BSD LICENSE
+ Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
+ All rights reserved.
+
+ Redistribution and use in source and binary forms, with or without
+ modification, are permitted provided that the following conditions
+ are met:
+
+ * Redistributions of source code must retain the above copyright
+ notice, this list of conditions and the following disclaimer.
+ * Redistributions in binary form must reproduce the above copyright
+ notice, this list of conditions and the following disclaimer in
+ the documentation and/or other materials provided with the
+ distribution.
+ * Neither the name of Intel Corporation nor the names of its
+ contributors may be used to endorse or promote products derived
+ from this software without specific prior written permission.
+
+ THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+Poll Mode Driver for Paravirtual VMXNET3 NIC
+============================================
+
+The VMXNET3 adapter is the next generation of a paravirtualized NIC, introduced by VMware* ESXi.
+It is designed for performance and is not related to VMXNET or VMXENET2.
+It offers all the features available in VMXNET2, and adds several new features such as,
+multi-queue support (also known as Receive Side Scaling, RSS),
+IPv6 offloads, and MSI/MSI-X interrupt delivery.
+Because operating system vendors do not provide built-in drivers for this card,
+VMware Tools must be installed to have a driver for the VMXNET3 network adapter available.
+One can use the same device in a DPDK application with VMXNET3 PMD introduced in DPDK API.
+
+Currently, the driver provides basic support for using the device in a DPDK application running on a guest OS.
+Optimization is needed on the backend, that is, the VMware* ESXi vmkernel switch, to achieve optimal performance end-to-end.
+
+In this chapter, two setups with the use of the VMXNET3 PMD are demonstrated:
+
+#. Vmxnet3 with a native NIC connected to a vSwitch
+
+#. Vmxnet3 chaining VMs connected to a vSwitch
+
+VMXNET3 Implementation in the DPDK
+----------------------------------
+
+For details on the VMXNET3 device, refer to the VMXNET3 driver's vmxnet3 directory and support manual from VMware*.
+
+For performance details, refer to the following link from VMware:
+
+`http://www.vmware.com/pdf/vsp_4_vmxnet3_perf.pdf <http://www.vmware.com/pdf/vsp_4_vmxnet3_perf.pdf>`_
+
+As a PMD, the VMXNET3 driver provides the packet reception and transmission callbacks, vmxnet3_recv_pkts and vmxnet3_xmit_pkts.
+It does not support scattered packet reception as part of vmxnet3_recv_pkts and vmxnet3_xmit_pkts.
+Also, it does not support scattered packet reception as part of the device operations supported.
+
+The VMXNET3 PMD handles all the packet buffer memory allocation and resides in guest address space
+and it is solely responsible to free that memory when not needed.
+The packet buffers and features to be supported are made available to hypervisor via VMXNET3 PCI configuration space BARs.
+During RX/TX, the packet buffers are exchanged by their GPAs,
+and the hypervisor loads the buffers with packets in the RX case and sends packets to vSwitch in the TX case.
+
+The VMXNET3 PMD is compiled with vmxnet3 device headers.
+The interface is similar to that of the other PMDs available in the DPDK API.
+The driver pre-allocates the packet buffers and loads the command ring descriptors in advance.
+The hypervisor fills those packet buffers on packet arrival and write completion ring descriptors,
+which are eventually pulled by the PMD.
+After reception, the DPDK application frees the descriptors and loads new packet buffers for the coming packets.
+The interrupts are disabled and there is no notification required.
+This keeps performance up on the RX side, even though the device provides a notification feature.
+
+In the transmit routine, the DPDK application fills packet buffer pointers in the descriptors of the command ring
+and notifies the hypervisor.
+In response the hypervisor takes packets and passes them to the vSwitch. It writes into the completion descriptors ring.
+The rings are read by the PMD in the next transmit routine call and the buffers and descriptors are freed from memory.
+
+Features and Limitations of VMXNET3 PMD
+---------------------------------------
+
+In release 1.6.0, the VMXNET3 PMD provides the basic functionality of packet reception and transmission.
+There are several options available for filtering packets at VMXNET3 device level including:
+
+#. MAC Address based filtering:
+
+ * Unicast, Broadcast, All Multicast modes - SUPPORTED BY DEFAULT
+
+ * Multicast with Multicast Filter table - NOT SUPPORTED
+
+ * Promiscuous mode - SUPPORTED
+
+ * RSS based load balancing between queues - SUPPORTED
+
+#. VLAN filtering:
+
+ * VLAN tag based filtering without load balancing - SUPPORTED
+
+.. note::
+
+
+ * Release 1.6.0 does not support separate headers and body receive cmd_ring and hence,
+ multiple segment buffers are not supported.
+ Only cmd_ring_0 is used for packet buffers, one for each descriptor.
+
+ * Receive and transmit of scattered packets is not supported.
+
+ * Multicast with Multicast Filter table is not supported.
+
+Prerequisites
+-------------
+
+The following prerequisites apply:
+
+* Before starting a VM, a VMXNET3 interface to a VM through VMware vSphere Client must be assigned.
+ This is shown in the figure below.
+
+.. _figure_vmxnet3_int:
+
+.. figure:: img/vmxnet3_int.*
+
+ Assigning a VMXNET3 interface to a VM using VMware vSphere Client
+
+.. note::
+
+ Depending on the Virtual Machine type, the VMware vSphere Client shows Ethernet adaptors while adding an Ethernet device.
+ Ensure that the VM type used offers a VMXNET3 device. Refer to the VMware documentation for a listed of VMs.
+
+.. note::
+
+ Follow the *DPDK Getting Started Guide* to setup the basic DPDK environment.
+
+.. note::
+
+ Follow the *DPDK Sample Application's User Guide*, L2 Forwarding/L3 Forwarding and
+ TestPMD for instructions on how to run a DPDK application using an assigned VMXNET3 device.
+
+VMXNET3 with a Native NIC Connected to a vSwitch
+------------------------------------------------
+
+This section describes an example setup for Phy-vSwitch-VM-Phy communication.
+
+.. _figure_vswitch_vm:
+
+.. figure:: img/vswitch_vm.*
+
+ VMXNET3 with a Native NIC Connected to a vSwitch
+
+.. note::
+
+ Other instructions on preparing to use DPDK such as, hugepage enabling, uio port binding are not listed here.
+ Please refer to *DPDK Getting Started Guide and DPDK Sample Application's User Guide* for detailed instructions.
+
+The packet reception and transmission flow path is::
+
+ Packet generator -> 82576
+ -> VMware ESXi vSwitch
+ -> VMXNET3 device
+ -> Guest VM VMXNET3 port 0 rx burst
+ -> Guest VM 82599 VF port 0 tx burst
+ -> 82599 VF
+ -> Packet generator
+
+VMXNET3 Chaining VMs Connected to a vSwitch
+-------------------------------------------
+
+The following figure shows an example VM-to-VM communication over a Phy-VM-vSwitch-VM-Phy communication channel.
+
+.. _figure_vm_vm_comms:
+
+.. figure:: img/vm_vm_comms.*
+
+ VMXNET3 Chaining VMs Connected to a vSwitch
+
+.. note::
+
+ When using the L2 Forwarding or L3 Forwarding applications,
+ a destination MAC address needs to be written in packets to hit the other VM's VMXNET3 interface.
+
+In this example, the packet flow path is::
+
+ Packet generator -> 82599 VF
+ -> Guest VM 82599 port 0 rx burst
+ -> Guest VM VMXNET3 port 1 tx burst
+ -> VMXNET3 device
+ -> VMware ESXi vSwitch
+ -> VMXNET3 device
+ -> Guest VM VMXNET3 port 0 rx burst
+ -> Guest VM 82599 VF port 1 tx burst
+ -> 82599 VF
+ -> Packet generator
Code Review / deb_dpdk.git / blobdiff