[dpdk-dev] [PATCH v12] net/tap: new TUN/TAP device PMD

Keith Wiles keith.wiles at intel.com
Mon Dec 12 15:38:38 CET 2016


The PMD allows for DPDK and the host to communicate using a raw
device interface on the host and in the DPDK application. The device
created is a Tap device with a L2 packet header.

v12- Fixup minor changes for driver_name and version number
v11- Add the tap.rst to the nic/index.rst file
v10- Change the string name used to allow for multiple devices.
v9 - Fix up the docs to use correct syntax
v8 - Fix issue with tap_tx_queue_setup() not return zero on success.
v7 - Reword the comment in common_base and fix the data->name issue
v6 - fixed the checkpatch issues
v5 - merge in changes from list review see related emails
     fixed many minor edits
v4 - merge with latest driver changes
v3 - fix includes by removing ifdef for other type besides Linux
     Fix the copyright notice in the Makefile
v2 - merge all of the patches into one patch
     Fix a typo on naming the tap device
     Update the maintainers list

Signed-off-by: Keith Wiles <keith.wiles at intel.com>
---
 MAINTAINERS                             |   5 +
 config/common_base                      |   9 +
 config/common_linuxapp                  |   1 +
 doc/guides/nics/index.rst               |   1 +
 doc/guides/nics/tap.rst                 | 136 ++++++
 drivers/net/Makefile                    |   1 +
 drivers/net/tap/Makefile                |  57 +++
 drivers/net/tap/rte_eth_tap.c           | 765 ++++++++++++++++++++++++++++++++
 drivers/net/tap/rte_pmd_tap_version.map |   4 +
 mk/rte.app.mk                           |   1 +
 10 files changed, 980 insertions(+)
 create mode 100644 doc/guides/nics/tap.rst
 create mode 100644 drivers/net/tap/Makefile
 create mode 100644 drivers/net/tap/rte_eth_tap.c
 create mode 100644 drivers/net/tap/rte_pmd_tap_version.map

diff --git a/MAINTAINERS b/MAINTAINERS
index 26d9590..842fb6d 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -398,6 +398,11 @@ F: doc/guides/nics/pcap_ring.rst
 F: app/test/test_pmd_ring.c
 F: app/test/test_pmd_ring_perf.c
 
+Tap PMD
+M: Keith Wiles <keith.wiles at intel.com>
+F: drivers/net/tap
+F: doc/guides/nics/tap.rst
+
 Null Networking PMD
 M: Tetsuya Mukawa <mtetsuyah at gmail.com>
 F: drivers/net/null/
diff --git a/config/common_base b/config/common_base
index 652a839..eb51cdb 100644
--- a/config/common_base
+++ b/config/common_base
@@ -590,3 +590,12 @@ CONFIG_RTE_APP_TEST_RESOURCE_TAR=n
 CONFIG_RTE_TEST_PMD=y
 CONFIG_RTE_TEST_PMD_RECORD_CORE_CYCLES=n
 CONFIG_RTE_TEST_PMD_RECORD_BURST_STATS=n
+
+#
+# Compile the TAP PMD
+#
+# The TAP PMD is currently only built for Linux and the
+# option is enabled by default in common_linuxapp file,
+# set to 'n' in the common_base file.
+#
+CONFIG_RTE_LIBRTE_PMD_TAP=n
diff --git a/config/common_linuxapp b/config/common_linuxapp
index 2483dfa..782b503 100644
--- a/config/common_linuxapp
+++ b/config/common_linuxapp
@@ -44,3 +44,4 @@ CONFIG_RTE_LIBRTE_PMD_VHOST=y
 CONFIG_RTE_LIBRTE_PMD_AF_PACKET=y
 CONFIG_RTE_LIBRTE_POWER=y
 CONFIG_RTE_VIRTIO_USER=y
+CONFIG_RTE_LIBRTE_PMD_TAP=y
diff --git a/doc/guides/nics/index.rst b/doc/guides/nics/index.rst
index 92d56a5..af92529 100644
--- a/doc/guides/nics/index.rst
+++ b/doc/guides/nics/index.rst
@@ -51,6 +51,7 @@ Network Interface Controller Drivers
     nfp
     qede
     szedata2
+    tap
     thunderx
     virtio
     vhost
diff --git a/doc/guides/nics/tap.rst b/doc/guides/nics/tap.rst
new file mode 100644
index 0000000..622b9e7
--- /dev/null
+++ b/doc/guides/nics/tap.rst
@@ -0,0 +1,136 @@
+..  BSD LICENSE
+    Copyright(c) 2016 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.
+
+Tun/Tap Poll Mode Driver
+========================
+
+The ``rte_eth_tap.c`` PMD creates a device using TUN/TAP interfaces on the
+local host. The PMD allows for DPDK and the host to communicate using a raw
+device interface on the host and in the DPDK application.
+
+The device created is a TAP device, which sends/receives packet in a raw
+format with a L2 header. The usage for a TAP PMD is for connectivity to the
+local host using a TAP interface. When the TAP PMD is initialized it will
+create a number of tap devices in the host accessed via ``ifconfig -a`` or
+``ip`` command. The commands can be used to assign and query the virtual like
+device.
+
+These TAP interfaces can be used with Wireshark or tcpdump or Pktgen-DPDK
+along with being able to be used as a network connection to the DPDK
+application. The method enable one or more interfaces is to use the
+``--vdev=net_tap`` option on the DPDK application command line. Each
+``--vdev=net_tap`` option give will create an interface named dtap0, dtap1,
+and so on.
+
+The interfaced name can be changed by adding the ``iface=foo0``, for example::
+
+   --vdev=net_tap,iface=foo0 --vdev=net_tap,iface=foo1, ...
+
+Also the speed of the interface can be changed from 10G to whatever number
+needed, but the interface does not enforce that speed, for example::
+
+   --vdev=net_tap,iface=foo0,speed=25000
+
+After the DPDK application is started you can send and receive packets on the
+interface using the standard rx_burst/tx_burst APIs in DPDK. From the host
+point of view you can use any host tool like tcpdump, Wireshark, ping, Pktgen
+and others to communicate with the DPDK application. The DPDK application may
+not understand network protocols like IPv4/6, UDP or TCP unless the
+application has been written to understand these protocols.
+
+If you need the interface as a real network interface meaning running and has
+a valid IP address then you can do this with the following commands::
+
+   sudo ip link set dtap0 up; sudo ip addr add 192.168.0.250/24 dev dtap0
+   sudo ip link set dtap1 up; sudo ip addr add 192.168.1.250/24 dev dtap1
+
+Please change the IP addresses as you see fit.
+
+If routing is enabled on the host you can also communicate with the DPDK App
+over the internet via a standard socket layer application as long as you
+account for the protocol handing in the application.
+
+If you have a Network Stack in your DPDK application or something like it you
+can utilize that stack to handle the network protocols. Plus you would be able
+to address the interface using an IP address assigned to the internal
+interface.
+
+Example
+-------
+
+The following is a simple example of using the TUN/TAP PMD with the Pktgen
+packet generator. It requires that the ``socat`` utility is installed on the
+test system.
+
+Build DPDK, then pull down Pktgen and build pktgen using the DPDK SDK/Target
+used to build the dpdk you pulled down.
+
+Run pktgen from the pktgen directory in a terminal with a commandline like the
+following::
+
+    sudo ./app/app/x86_64-native-linuxapp-gcc/app/pktgen -l 1-5 -n 4        \
+     --proc-type auto --log-level 8 --socket-mem 512,512 --file-prefix pg   \
+     --vdev=net_tap --vdev=net_tap -b 05:00.0 -b 05:00.1                    \
+     -b 04:00.0 -b 04:00.1 -b 04:00.2 -b 04:00.3                            \
+     -b 81:00.0 -b 81:00.1 -b 81:00.2 -b 81:00.3                            \
+     -b 82:00.0 -b 83:00.0 -- -T -P -m [2:3].0 -m [4:5].1                   \
+     -f themes/black-yellow.theme
+
+.. Note:
+
+   Change the ``-b`` options to blacklist all of your physical ports. The
+   following command line is all one line.
+
+   Also, ``-f themes/black-yellow.theme`` is optional if the default colors
+   work on your system configuration. See the Pktgen docs for more
+   information.
+
+Verify with ``ifconfig -a`` command in a different xterm window, should have a
+``dtap0`` and ``dtap1`` interfaces created.
+
+Next set the links for the two interfaces to up via the commands below::
+
+    sudo ip link set dtap0 up; sudo ip addr add 192.168.0.250/24 dev dtap0
+    sudo ip link set dtap1 up; sudo ip addr add 192.168.1.250/24 dev dtap1
+
+Then use socat to create a loopback for the two interfaces::
+
+    sudo socat interface:dtap0 interface:dtap1
+
+Then on the Pktgen command line interface you can start sending packets using
+the commands ``start 0`` and ``start 1`` or you can start both at the same
+time with ``start all``. The command ``str`` is an alias for ``start all`` and
+``stp`` is an alias for ``stop all``.
+
+While running you should see the 64 byte counters increasing to verify the
+traffic is being looped back. You can use ``set all size XXX`` to change the
+size of the packets after you stop the traffic. Use the pktgen ``help``
+command to see a list of all commands. You can also use the ``-f`` option to
+load commands at startup.
diff --git a/drivers/net/Makefile b/drivers/net/Makefile
index bc93230..e366a85 100644
--- a/drivers/net/Makefile
+++ b/drivers/net/Makefile
@@ -51,6 +51,7 @@ DIRS-$(CONFIG_RTE_LIBRTE_PMD_PCAP) += pcap
 DIRS-$(CONFIG_RTE_LIBRTE_QEDE_PMD) += qede
 DIRS-$(CONFIG_RTE_LIBRTE_PMD_RING) += ring
 DIRS-$(CONFIG_RTE_LIBRTE_PMD_SZEDATA2) += szedata2
+DIRS-$(CONFIG_RTE_LIBRTE_PMD_TAP) += tap
 DIRS-$(CONFIG_RTE_LIBRTE_THUNDERX_NICVF_PMD) += thunderx
 DIRS-$(CONFIG_RTE_LIBRTE_VIRTIO_PMD) += virtio
 DIRS-$(CONFIG_RTE_LIBRTE_VMXNET3_PMD) += vmxnet3
diff --git a/drivers/net/tap/Makefile b/drivers/net/tap/Makefile
new file mode 100644
index 0000000..e18f30c
--- /dev/null
+++ b/drivers/net/tap/Makefile
@@ -0,0 +1,57 @@
+#   BSD LICENSE
+#
+#   Copyright(c) 2016 Intel Corporation. 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.
+
+include $(RTE_SDK)/mk/rte.vars.mk
+
+#
+# library name
+#
+LIB = librte_pmd_tap.a
+
+EXPORT_MAP := rte_pmd_tap_version.map
+
+LIBABIVER := 1
+
+CFLAGS += -O3
+CFLAGS += $(WERROR_FLAGS)
+
+#
+# all source are stored in SRCS-y
+#
+SRCS-$(CONFIG_RTE_LIBRTE_PMD_TAP) += rte_eth_tap.c
+
+# this lib depends upon:
+DEPDIRS-$(CONFIG_RTE_LIBRTE_PMD_TAP) += lib/librte_eal
+DEPDIRS-$(CONFIG_RTE_LIBRTE_PMD_TAP) += lib/librte_mbuf
+DEPDIRS-$(CONFIG_RTE_LIBRTE_PMD_TAP) += lib/librte_mempool
+DEPDIRS-$(CONFIG_RTE_LIBRTE_PMD_TAP) += lib/librte_ether
+DEPDIRS-$(CONFIG_RTE_LIBRTE_PMD_TAP) += lib/librte_kvargs
+
+include $(RTE_SDK)/mk/rte.lib.mk
diff --git a/drivers/net/tap/rte_eth_tap.c b/drivers/net/tap/rte_eth_tap.c
new file mode 100644
index 0000000..976f2d9
--- /dev/null
+++ b/drivers/net/tap/rte_eth_tap.c
@@ -0,0 +1,765 @@
+/*-
+ *   BSD LICENSE
+ *
+ *   Copyright(c) 2016 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.
+ */
+
+#include <rte_mbuf.h>
+#include <rte_ethdev.h>
+#include <rte_malloc.h>
+#include <rte_vdev.h>
+#include <rte_kvargs.h>
+
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/socket.h>
+#include <sys/ioctl.h>
+#include <sys/mman.h>
+#include <unistd.h>
+#include <poll.h>
+#include <arpa/inet.h>
+#include <linux/if.h>
+#include <linux/if_tun.h>
+#include <linux/if_ether.h>
+#include <fcntl.h>
+
+/* Linux based path to the TUN device */
+#define TUN_TAP_DEV_PATH        "/dev/net/tun"
+#define DEFAULT_TAP_NAME        "dtap"
+
+#define ETH_TAP_IFACE_ARG       "iface"
+#define ETH_TAP_SPEED_ARG       "speed"
+
+#define RTE_PMD_TAP_MAX_QUEUES	16
+
+static struct rte_vdev_driver pmd_tap_drv;
+
+static const char *valid_arguments[] = {
+	ETH_TAP_IFACE_ARG,
+	ETH_TAP_SPEED_ARG,
+	NULL
+};
+
+static int tap_unit;
+
+static struct rte_eth_link pmd_link = {
+	.link_speed = ETH_SPEED_NUM_10G,
+	.link_duplex = ETH_LINK_FULL_DUPLEX,
+	.link_status = ETH_LINK_DOWN,
+	.link_autoneg = ETH_LINK_SPEED_AUTONEG
+};
+
+struct pkt_stats {
+	uint64_t opackets;		/* Number of output packets */
+	uint64_t ipackets;		/* Number of input packets */
+	uint64_t obytes;		/* Number of bytes on output */
+	uint64_t ibytes;		/* Number of bytes on input */
+	uint64_t errs;			/* Number of error packets */
+};
+
+struct rx_queue {
+	struct rte_mempool *mp;		/* Mempool for RX packets */
+	uint16_t in_port;		/* Port ID */
+	int fd;
+
+	struct pkt_stats stats;		/* Stats for this RX queue */
+};
+
+struct tx_queue {
+	int fd;
+	struct pkt_stats stats;		/* Stats for this TX queue */
+};
+
+struct pmd_internals {
+	char name[RTE_ETH_NAME_MAX_LEN];	/* Internal Tap device name */
+	uint16_t nb_queues;		/* Number of queues supported */
+	struct ether_addr eth_addr;	/* Mac address of the device port */
+
+	int if_index;			/* IF_INDEX for the port */
+	int fds[RTE_PMD_TAP_MAX_QUEUES]; /* List of all file descriptors */
+
+	struct rx_queue rxq[RTE_PMD_TAP_MAX_QUEUES];	/* List of RX queues */
+	struct tx_queue txq[RTE_PMD_TAP_MAX_QUEUES];	/* List of TX queues */
+};
+
+/* Tun/Tap allocation routine
+ *
+ * name is the number of the interface to use, unless NULL to take the host
+ * supplied name.
+ */
+static int
+tun_alloc(char *name)
+{
+	struct ifreq ifr;
+	unsigned int features;
+	int fd;
+
+	memset(&ifr, 0, sizeof(struct ifreq));
+
+	ifr.ifr_flags = IFF_TAP | IFF_NO_PI;
+	if (name && name[0])
+		strncpy(ifr.ifr_name, name, IFNAMSIZ);
+
+	fd = open(TUN_TAP_DEV_PATH, O_RDWR);
+	if (fd < 0) {
+		RTE_LOG(ERR, PMD, "Unable to create TAP interface");
+		goto error;
+	}
+
+	/* Grab the TUN features to verify we can work */
+	if (ioctl(fd, TUNGETFEATURES, &features) < 0) {
+		RTE_LOG(ERR, PMD, "Unable to get TUN/TAP features\n");
+		goto error;
+	}
+	RTE_LOG(DEBUG, PMD, "TUN/TAP Features %08x\n", features);
+
+	if (!(features & IFF_MULTI_QUEUE) && (RTE_PMD_TAP_MAX_QUEUES > 1)) {
+		RTE_LOG(DEBUG, PMD, "TUN/TAP device only one queue\n");
+		goto error;
+	} else if ((features & IFF_ONE_QUEUE) &&
+			(RTE_PMD_TAP_MAX_QUEUES == 1)) {
+		ifr.ifr_flags |= IFF_ONE_QUEUE;
+		RTE_LOG(DEBUG, PMD, "Single queue only support\n");
+	} else {
+		ifr.ifr_flags |= IFF_MULTI_QUEUE;
+		RTE_LOG(DEBUG, PMD, "Multi-queue support for %d queues\n",
+			RTE_PMD_TAP_MAX_QUEUES);
+	}
+
+	/* Set the TUN/TAP configuration and get the name if needed */
+	if (ioctl(fd, TUNSETIFF, (void *)&ifr) < 0) {
+		RTE_LOG(ERR, PMD, "Unable to set TUNSETIFF for %s\n",
+			ifr.ifr_name);
+		perror("TUNSETIFF");
+		goto error;
+	}
+
+	/* Always set the file descriptor to non-blocking */
+	if (fcntl(fd, F_SETFL, O_NONBLOCK) < 0) {
+		RTE_LOG(ERR, PMD, "Unable to set to nonblocking\n");
+		perror("F_SETFL, NONBLOCK");
+		goto error;
+	}
+
+	/* If the name is different that new name as default */
+	if (name && strcmp(name, ifr.ifr_name))
+		snprintf(name, RTE_ETH_NAME_MAX_LEN - 1, "%s", ifr.ifr_name);
+
+	return fd;
+
+error:
+	if (fd > 0)
+		close(fd);
+	return -1;
+}
+
+/* Callback to handle the rx burst of packets to the correct interface and
+ * file descriptor(s) in a multi-queue setup.
+ */
+static uint16_t
+pmd_rx_burst(void *queue, struct rte_mbuf **bufs, uint16_t nb_pkts)
+{
+	int len;
+	struct rte_mbuf *mbuf;
+	struct rx_queue *rxq = queue;
+	uint16_t num_rx;
+	unsigned long num_rx_bytes = 0;
+
+	for (num_rx = 0; num_rx < nb_pkts; ) {
+		/* allocate the next mbuf */
+		mbuf = rte_pktmbuf_alloc(rxq->mp);
+		if (unlikely(!mbuf)) {
+			RTE_LOG(WARNING, PMD, "Unable to allocate mbuf\n");
+			break;
+		}
+
+		len = read(rxq->fd, rte_pktmbuf_mtod(mbuf, char *),
+			   rte_pktmbuf_tailroom(mbuf));
+		if (len <= 0) {
+			rte_pktmbuf_free(mbuf);
+			break;
+		}
+
+		mbuf->data_len = len;
+		mbuf->pkt_len = len;
+		mbuf->port = rxq->in_port;
+
+		/* account for the receive frame */
+		bufs[num_rx++] = mbuf;
+		num_rx_bytes += mbuf->pkt_len;
+	}
+	rxq->stats.ipackets += num_rx;
+	rxq->stats.ibytes += num_rx_bytes;
+
+	return num_rx;
+}
+
+/* Callback to handle sending packets from the tap interface
+ */
+static uint16_t
+pmd_tx_burst(void *queue, struct rte_mbuf **bufs, uint16_t nb_pkts)
+{
+	struct rte_mbuf *mbuf;
+	struct tx_queue *txq = queue;
+	struct pollfd pfd;
+	uint16_t num_tx = 0;
+	unsigned long num_tx_bytes = 0;
+	int i, n;
+
+	if (unlikely(nb_pkts == 0))
+		return 0;
+
+	pfd.events = POLLOUT;
+	pfd.fd = txq->fd;
+	for (i = 0; i < nb_pkts; i++) {
+		n = poll(&pfd, 1, 0);
+
+		if (n <= 0)
+			break;
+
+		if (pfd.revents & POLLOUT) {
+			/* copy the tx frame data */
+			mbuf = bufs[num_tx];
+			n = write(pfd.fd, rte_pktmbuf_mtod(mbuf, void*),
+				  rte_pktmbuf_pkt_len(mbuf));
+			if (n <= 0)
+				break;
+
+			num_tx++;
+			num_tx_bytes += mbuf->pkt_len;
+			rte_pktmbuf_free(mbuf);
+		}
+	}
+
+	txq->stats.opackets += num_tx;
+	txq->stats.errs += nb_pkts - num_tx;
+	txq->stats.obytes += num_tx_bytes;
+
+	return num_tx;
+}
+
+static int
+tap_dev_start(struct rte_eth_dev *dev)
+{
+	/* Force the Link up */
+	dev->data->dev_link.link_status = ETH_LINK_UP;
+
+	return 0;
+}
+
+/* This function gets called when the current port gets stopped.
+ */
+static void
+tap_dev_stop(struct rte_eth_dev *dev)
+{
+	int i;
+	struct pmd_internals *internals = dev->data->dev_private;
+
+	for (i = 0; i < internals->nb_queues; i++)
+		if (internals->fds[i] != -1)
+			close(internals->fds[i]);
+
+	dev->data->dev_link.link_status = ETH_LINK_DOWN;
+}
+
+static int
+tap_dev_configure(struct rte_eth_dev *dev __rte_unused)
+{
+	return 0;
+}
+
+static void
+tap_dev_info(struct rte_eth_dev *dev, struct rte_eth_dev_info *dev_info)
+{
+	struct pmd_internals *internals = dev->data->dev_private;
+
+	dev_info->if_index = internals->if_index;
+	dev_info->max_mac_addrs = 1;
+	dev_info->max_rx_pktlen = (uint32_t)ETHER_MAX_VLAN_FRAME_LEN;
+	dev_info->max_rx_queues = internals->nb_queues;
+	dev_info->max_tx_queues = internals->nb_queues;
+	dev_info->min_rx_bufsize = 0;
+	dev_info->pci_dev = NULL;
+}
+
+static void
+tap_stats_get(struct rte_eth_dev *dev, struct rte_eth_stats *tap_stats)
+{
+	unsigned int i, imax;
+	unsigned long rx_total = 0, tx_total = 0, tx_err_total = 0;
+	unsigned long rx_bytes_total = 0, tx_bytes_total = 0;
+	const struct pmd_internals *pmd = dev->data->dev_private;
+
+	imax = (pmd->nb_queues < RTE_ETHDEV_QUEUE_STAT_CNTRS) ?
+		pmd->nb_queues : RTE_ETHDEV_QUEUE_STAT_CNTRS;
+
+	for (i = 0; i < imax; i++) {
+		tap_stats->q_ipackets[i] = pmd->rxq[i].stats.ipackets;
+		tap_stats->q_ibytes[i] = pmd->rxq[i].stats.ibytes;
+		rx_total += tap_stats->q_ipackets[i];
+		rx_bytes_total += tap_stats->q_ibytes[i];
+	}
+
+	for (i = 0; i < imax; i++) {
+		tap_stats->q_opackets[i] = pmd->txq[i].stats.opackets;
+		tap_stats->q_errors[i] = pmd->txq[i].stats.errs;
+		tap_stats->q_obytes[i] = pmd->txq[i].stats.obytes;
+		tx_total += tap_stats->q_opackets[i];
+		tx_err_total += tap_stats->q_errors[i];
+		tx_bytes_total += tap_stats->q_obytes[i];
+	}
+
+	tap_stats->ipackets = rx_total;
+	tap_stats->ibytes = rx_bytes_total;
+	tap_stats->opackets = tx_total;
+	tap_stats->oerrors = tx_err_total;
+	tap_stats->obytes = tx_bytes_total;
+}
+
+static void
+tap_stats_reset(struct rte_eth_dev *dev)
+{
+	int i;
+	struct pmd_internals *pmd = dev->data->dev_private;
+
+	for (i = 0; i < pmd->nb_queues; i++) {
+		pmd->rxq[i].stats.ipackets = 0;
+		pmd->rxq[i].stats.ibytes = 0;
+	}
+
+	for (i = 0; i < pmd->nb_queues; i++) {
+		pmd->txq[i].stats.opackets = 0;
+		pmd->txq[i].stats.errs = 0;
+		pmd->txq[i].stats.obytes = 0;
+	}
+}
+
+static void
+tap_dev_close(struct rte_eth_dev *dev __rte_unused)
+{
+}
+
+static void
+tap_rx_queue_release(void *queue)
+{
+	struct rx_queue *rxq = queue;
+
+	if (rxq && (rxq->fd > 0)) {
+		close(rxq->fd);
+		rxq->fd = -1;
+	}
+}
+
+static void
+tap_tx_queue_release(void *queue)
+{
+	struct tx_queue *txq = queue;
+
+	if (txq && (txq->fd > 0)) {
+		close(txq->fd);
+		txq->fd = -1;
+	}
+}
+
+static int
+tap_link_update(struct rte_eth_dev *dev __rte_unused,
+		int wait_to_complete __rte_unused)
+{
+	return 0;
+}
+
+static int
+tap_setup_queue(struct rte_eth_dev *dev,
+		struct pmd_internals *internals,
+		uint16_t qid)
+{
+	struct rx_queue *rx = &internals->rxq[qid];
+	struct tx_queue *tx = &internals->txq[qid];
+	int fd;
+
+	fd = rx->fd;
+	if (fd < 0) {
+		fd = tx->fd;
+		if (fd < 0) {
+			RTE_LOG(INFO, PMD, "Add queue to TAP %s for qid %d\n",
+				dev->data->name, qid);
+			fd = tun_alloc(dev->data->name);
+			if (fd < 0) {
+				RTE_LOG(ERR, PMD, "tun_alloc(%s) failed\n",
+					dev->data->name);
+				return -1;
+			}
+		}
+	}
+	dev->data->rx_queues[qid] = rx;
+	dev->data->tx_queues[qid] = tx;
+
+	rx->fd = fd;
+	tx->fd = fd;
+
+	return fd;
+}
+
+static int
+tap_rx_queue_setup(struct rte_eth_dev *dev,
+		   uint16_t rx_queue_id,
+		   uint16_t nb_rx_desc __rte_unused,
+		   unsigned int socket_id __rte_unused,
+		   const struct rte_eth_rxconf *rx_conf __rte_unused,
+		   struct rte_mempool *mp)
+{
+	struct pmd_internals *internals = dev->data->dev_private;
+	uint16_t buf_size;
+	int fd;
+
+	if ((rx_queue_id >= internals->nb_queues) || !mp) {
+		RTE_LOG(ERR, PMD, "nb_queues %d mp %p\n",
+			internals->nb_queues, mp);
+		return -1;
+	}
+
+	internals->rxq[rx_queue_id].mp = mp;
+	internals->rxq[rx_queue_id].in_port = dev->data->port_id;
+
+	/* Now get the space available for data in the mbuf */
+	buf_size = (uint16_t)(rte_pktmbuf_data_room_size(mp) -
+				RTE_PKTMBUF_HEADROOM);
+
+	if (buf_size < ETH_FRAME_LEN) {
+		RTE_LOG(ERR, PMD,
+			"%s: %d bytes will not fit in mbuf (%d bytes)\n",
+			dev->data->name, ETH_FRAME_LEN, buf_size);
+		return -ENOMEM;
+	}
+
+	fd = tap_setup_queue(dev, internals, rx_queue_id);
+	if (fd == -1)
+		return -1;
+
+	internals->fds[rx_queue_id] = fd;
+	RTE_LOG(INFO, PMD, "RX TAP device name %s, qid %d on fd %d\n",
+		dev->data->name, rx_queue_id, internals->rxq[rx_queue_id].fd);
+
+	return 0;
+}
+
+static int
+tap_tx_queue_setup(struct rte_eth_dev *dev,
+		   uint16_t tx_queue_id,
+		   uint16_t nb_tx_desc __rte_unused,
+		   unsigned int socket_id __rte_unused,
+		   const struct rte_eth_txconf *tx_conf __rte_unused)
+{
+	struct pmd_internals *internals = dev->data->dev_private;
+	int ret;
+
+	if (tx_queue_id >= internals->nb_queues)
+		return -1;
+
+	ret = tap_setup_queue(dev, internals, tx_queue_id);
+	if (ret == -1)
+		return -1;
+
+	RTE_LOG(INFO, PMD, "TX TAP device name %s, qid %d on fd %d\n",
+		dev->data->name, tx_queue_id, internals->txq[tx_queue_id].fd);
+
+	return 0;
+}
+
+static const struct eth_dev_ops ops = {
+	.dev_start              = tap_dev_start,
+	.dev_stop               = tap_dev_stop,
+	.dev_close              = tap_dev_close,
+	.dev_configure          = tap_dev_configure,
+	.dev_infos_get          = tap_dev_info,
+	.rx_queue_setup         = tap_rx_queue_setup,
+	.tx_queue_setup         = tap_tx_queue_setup,
+	.rx_queue_release       = tap_rx_queue_release,
+	.tx_queue_release       = tap_tx_queue_release,
+	.link_update            = tap_link_update,
+	.stats_get              = tap_stats_get,
+	.stats_reset            = tap_stats_reset,
+};
+
+static int
+pmd_mac_address(int fd, struct rte_eth_dev *dev, struct ether_addr *addr)
+{
+	struct ifreq ifr;
+
+	if ((fd <= 0) || !dev || !addr)
+		return -1;
+
+	memset(&ifr, 0, sizeof(ifr));
+
+	if (ioctl(fd, SIOCGIFHWADDR, &ifr) == -1) {
+		RTE_LOG(ERR, PMD, "ioctl failed (SIOCGIFHWADDR) (%s)\n",
+			ifr.ifr_name);
+		return -1;
+	}
+
+	/* Set the host based MAC address to this special MAC format */
+	ifr.ifr_hwaddr.sa_data[0] = 'T';
+	ifr.ifr_hwaddr.sa_data[1] = 'a';
+	ifr.ifr_hwaddr.sa_data[2] = 'p';
+	ifr.ifr_hwaddr.sa_data[3] = '-';
+	ifr.ifr_hwaddr.sa_data[4] = dev->data->port_id;
+	ifr.ifr_hwaddr.sa_data[5] = dev->data->numa_node;
+	if (ioctl(fd, SIOCSIFHWADDR, &ifr) == -1) {
+		RTE_LOG(ERR, PMD, "%s: ioctl failed (SIOCSIFHWADDR) (%s)\n",
+			dev->data->name, ifr.ifr_name);
+		return -1;
+	}
+
+	/* Set the local application MAC address, needs to be different then
+	 * the host based MAC address.
+	 */
+	ifr.ifr_hwaddr.sa_data[0] = 'd';
+	ifr.ifr_hwaddr.sa_data[1] = 'n';
+	ifr.ifr_hwaddr.sa_data[2] = 'e';
+	ifr.ifr_hwaddr.sa_data[3] = 't';
+	ifr.ifr_hwaddr.sa_data[4] = dev->data->port_id;
+	ifr.ifr_hwaddr.sa_data[5] = dev->data->numa_node;
+	rte_memcpy(addr, ifr.ifr_hwaddr.sa_data, ETH_ALEN);
+
+	return 0;
+}
+
+static int
+eth_dev_tap_create(const char *name, char *tap_name)
+{
+	int numa_node = rte_socket_id();
+	struct rte_eth_dev *dev = NULL;
+	struct pmd_internals *pmd = NULL;
+	struct rte_eth_dev_data *data = NULL;
+	int i, fd = -1;
+
+	RTE_LOG(INFO, PMD,
+		"%s: Create TAP Ethernet device with %d queues on numa %u\n",
+		 name, RTE_PMD_TAP_MAX_QUEUES, rte_socket_id());
+
+	data = rte_zmalloc_socket(tap_name, sizeof(*data), 0, numa_node);
+	if (!data) {
+		RTE_LOG(INFO, PMD, "Failed to allocate data\n");
+		goto error_exit;
+	}
+
+	pmd = rte_zmalloc_socket(tap_name, sizeof(*pmd), 0, numa_node);
+	if (!pmd) {
+		RTE_LOG(INFO, PMD, "Unable to allocate internal struct\n");
+		goto error_exit;
+	}
+
+	/* Use the name and not the tap_name */
+	dev = rte_eth_dev_allocate(tap_name);
+	if (!dev) {
+		RTE_LOG(INFO, PMD, "Unable to allocate device struct\n");
+		goto error_exit;
+	}
+
+	snprintf(pmd->name, sizeof(pmd->name), "%s", tap_name);
+
+	pmd->nb_queues = RTE_PMD_TAP_MAX_QUEUES;
+
+	/* Setup some default values */
+	data->dev_private = pmd;
+	data->port_id = dev->data->port_id;
+	data->dev_flags = RTE_ETH_DEV_DETACHABLE;
+	data->kdrv = RTE_KDRV_NONE;
+	data->drv_name = pmd_tap_drv.driver.name;
+	data->numa_node = numa_node;
+
+	data->dev_link = pmd_link;
+	data->mac_addrs = &pmd->eth_addr;
+	data->nb_rx_queues = pmd->nb_queues;
+	data->nb_tx_queues = pmd->nb_queues;
+
+	dev->data = data;
+	dev->dev_ops = &ops;
+	dev->driver = NULL;
+	dev->rx_pkt_burst = pmd_rx_burst;
+	dev->tx_pkt_burst = pmd_tx_burst;
+	snprintf(dev->data->name, sizeof(dev->data->name), "%s", name);
+
+	/* Create the first Tap device */
+	fd = tun_alloc(tap_name);
+	if (fd < 0) {
+		RTE_LOG(INFO, PMD, "tun_alloc() failed\n");
+		goto error_exit;
+	}
+
+	/* Presetup the fds to -1 as being not working */
+	for (i = 0; i < RTE_PMD_TAP_MAX_QUEUES; i++) {
+		pmd->fds[i] = -1;
+		pmd->rxq[i].fd = -1;
+		pmd->txq[i].fd = -1;
+	}
+
+	/* Take the TUN/TAP fd and place in the first location */
+	pmd->rxq[0].fd = fd;
+	pmd->txq[0].fd = fd;
+	pmd->fds[0] = fd;
+
+	if (pmd_mac_address(fd, dev, &pmd->eth_addr) < 0) {
+		RTE_LOG(INFO, PMD, "Unable to get MAC address\n");
+		goto error_exit;
+	}
+
+	return 0;
+
+error_exit:
+	RTE_PMD_DEBUG_TRACE("Unable to initialize %s\n", name);
+
+	rte_free(data);
+	rte_free(pmd);
+
+	rte_eth_dev_release_port(dev);
+
+	return -EINVAL;
+}
+
+static int
+set_interface_name(const char *key __rte_unused,
+		   const char *value,
+		   void *extra_args)
+{
+	char *name = (char *)extra_args;
+
+	if (value)
+		snprintf(name, RTE_ETH_NAME_MAX_LEN - 1, "%s", value);
+	else
+		snprintf(name, RTE_ETH_NAME_MAX_LEN - 1, "%s%d",
+			 DEFAULT_TAP_NAME, (tap_unit - 1));
+
+	return 0;
+}
+
+static int
+set_interface_speed(const char *key __rte_unused,
+		    const char *value,
+		    void *extra_args)
+{
+	*(int *)extra_args = (value) ? atoi(value) : ETH_SPEED_NUM_10G;
+
+	return 0;
+}
+
+/* Open a TAP interface device.
+ */
+static int
+rte_pmd_tap_probe(const char *name, const char *params)
+{
+	int ret;
+	struct rte_kvargs *kvlist = NULL;
+	int speed;
+	char tap_name[RTE_ETH_NAME_MAX_LEN];
+
+	speed = ETH_SPEED_NUM_10G;
+	snprintf(tap_name, sizeof(tap_name), "%s%d",
+		 DEFAULT_TAP_NAME, tap_unit++);
+
+	RTE_LOG(INFO, PMD, "Initializing pmd_tap for %s as %s\n",
+		name, tap_name);
+
+	if (params && (params[0] != '\0')) {
+		RTE_LOG(INFO, PMD, "paramaters (%s)\n", params);
+
+		kvlist = rte_kvargs_parse(params, valid_arguments);
+		if (kvlist) {
+			if (rte_kvargs_count(kvlist, ETH_TAP_SPEED_ARG) == 1) {
+				ret = rte_kvargs_process(kvlist,
+							 ETH_TAP_SPEED_ARG,
+							 &set_interface_speed,
+							 &speed);
+				if (ret == -1)
+					goto leave;
+			}
+
+			if (rte_kvargs_count(kvlist, ETH_TAP_IFACE_ARG) == 1) {
+				ret = rte_kvargs_process(kvlist,
+							 ETH_TAP_IFACE_ARG,
+							 &set_interface_name,
+							 tap_name);
+				if (ret == -1)
+					goto leave;
+			}
+		}
+	}
+	pmd_link.link_speed = speed;
+
+	ret = eth_dev_tap_create(name, tap_name);
+
+leave:
+	if (ret == -1) {
+		RTE_LOG(INFO, PMD, "Failed to create pmd for %s as %s\n",
+			name, tap_name);
+		tap_unit--;		/* Restore the unit number */
+	}
+	rte_kvargs_free(kvlist);
+
+	return ret;
+}
+
+/* detach a TAP device.
+ */
+static int
+rte_pmd_tap_remove(const char *name)
+{
+	struct rte_eth_dev *eth_dev = NULL;
+	struct pmd_internals *internals;
+	int i;
+
+	RTE_LOG(INFO, PMD, "Closing TUN/TAP Ethernet device on numa %u\n",
+		rte_socket_id());
+
+	/* find the ethdev entry */
+	eth_dev = rte_eth_dev_allocated(name);
+	if (!eth_dev)
+		return 0;
+
+	internals = eth_dev->data->dev_private;
+	for (i = 0; i < internals->nb_queues; i++)
+		if (internals->fds[i] != -1)
+			close(internals->fds[i]);
+
+	rte_free(eth_dev->data->dev_private);
+	rte_free(eth_dev->data);
+
+	rte_eth_dev_release_port(eth_dev);
+
+	return 0;
+}
+
+static struct rte_vdev_driver pmd_tap_drv = {
+	.probe = rte_pmd_tap_probe,
+	.remove = rte_pmd_tap_remove,
+};
+RTE_PMD_REGISTER_VDEV(net_tap, pmd_tap_drv);
+RTE_PMD_REGISTER_ALIAS(net_tap, eth_tap);
+RTE_PMD_REGISTER_PARAM_STRING(net_tap, "iface=<string>,speed=N");
diff --git a/drivers/net/tap/rte_pmd_tap_version.map b/drivers/net/tap/rte_pmd_tap_version.map
new file mode 100644
index 0000000..31eca32
--- /dev/null
+++ b/drivers/net/tap/rte_pmd_tap_version.map
@@ -0,0 +1,4 @@
+DPDK_17.02 {
+
+	local: *;
+};
diff --git a/mk/rte.app.mk b/mk/rte.app.mk
index f75f0e2..02c32ae 100644
--- a/mk/rte.app.mk
+++ b/mk/rte.app.mk
@@ -124,6 +124,7 @@ _LDLIBS-$(CONFIG_RTE_LIBRTE_PMD_PCAP)       += -lrte_pmd_pcap -lpcap
 _LDLIBS-$(CONFIG_RTE_LIBRTE_QEDE_PMD)       += -lrte_pmd_qede
 _LDLIBS-$(CONFIG_RTE_LIBRTE_PMD_RING)       += -lrte_pmd_ring
 _LDLIBS-$(CONFIG_RTE_LIBRTE_PMD_SZEDATA2)   += -lrte_pmd_szedata2 -lsze2
+_LDLIBS-$(CONFIG_RTE_LIBRTE_PMD_TAP)        += -lrte_pmd_tap
 _LDLIBS-$(CONFIG_RTE_LIBRTE_THUNDERX_NICVF_PMD) += -lrte_pmd_thunderx_nicvf -lm
 _LDLIBS-$(CONFIG_RTE_LIBRTE_VIRTIO_PMD)     += -lrte_pmd_virtio
 ifeq ($(CONFIG_RTE_LIBRTE_VHOST),y)
-- 
2.8.0.GIT



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