[PATCH v5 2/2] net: Add support for NTB virtual ethernet device

Jon Mason
2012-11-06T00:11:31Z

A virtual ethernet device that uses the NTB transport API to
send/receive data.

Signed-off-by: Jon Mason <jon.mason@intel.com>
Reviewed-by: Nicholas Bellinger <nab@linux-iscsi.org>
---
MAINTAINERS | 1 +
drivers/net/Kconfig | 4 +
drivers/net/Makefile | 1 +
drivers/net/ntb_netdev.c | 415 ++++++++++++++++++++++++++++++++++++++++++++++
4 files changed, 421 insertions(+)
create mode 100644 drivers/net/ntb_netdev.c

diff --git a/MAINTAINERS b/MAINTAINERS
index e0fc24a..5c3059f 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -5148,6 +5148,7 @@ NTB DRIVER
M: Jon Mason <jon.mason@intel.com>
S: Supported
F: drivers/ntb/
+F: drivers/net/ntb_netdev.c
F: include/linux/ntb.h

NTFS FILESYSTEM
diff --git a/drivers/net/Kconfig b/drivers/net/Kconfig
index 6a70184..5db9acb 100644
--- a/drivers/net/Kconfig
+++ b/drivers/net/Kconfig
@@ -189,6 +189,10 @@ config NETPOLL_TRAP
config NET_POLL_CONTROLLER
def_bool NETPOLL

+config NTB_NETDEV
+ tristate "Virtual Ethernet over NTB"
+ depends on NTB
+
config RIONET
tristate "RapidIO Ethernet over messaging driver support"
depends on RAPIDIO
diff --git a/drivers/net/Makefile b/drivers/net/Makefile
index 335db78..ef3d090 100644
--- a/drivers/net/Makefile
+++ b/drivers/net/Makefile
@@ -71,3 +71,4 @@ obj-$(CONFIG_USB_IPHETH) += usb/
obj-$(CONFIG_USB_CDC_PHONET) += usb/

obj-$(CONFIG_HYPERV_NET) += hyperv/
+obj-$(CONFIG_NTB_NETDEV) += ntb_netdev.o
diff --git a/drivers/net/ntb_netdev.c b/drivers/net/ntb_netdev.c
new file mode 100644
index 0000000..c11df8c
--- /dev/null
+++ b/drivers/net/ntb_netdev.c
@@ -0,0 +1,415 @@
+/*
+ * This file is provided under a dual BSD/GPLv2 license. When using or
+ * redistributing this file, you may do so under either license.
+ *
+ * GPL LICENSE SUMMARY
+ *
+ * Copyright(c) 2012 Intel Corporation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ *
+ * BSD LICENSE
+ *
+ * Copyright(c) 2012 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 copy
+ * 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.
+ *
+ * Intel PCIe NTB Network Linux driver
+ *
+ * Contact Information:
+ * Jon Mason <jon.mason@intel.com>
+ */
+#include <linux/etherdevice.h>
+#include <linux/ethtool.h>
+#include <linux/module.h>
+#include <linux/pci.h>
+#include <linux/ntb.h>
+
+#define NTB_NETDEV_VER "0.6"
+
+MODULE_DESCRIPTION(KBUILD_MODNAME);
+MODULE_VERSION(NTB_NETDEV_VER);
+MODULE_LICENSE("Dual BSD/GPL");
+MODULE_AUTHOR("Intel Corporation");
+
+struct ntb_netdev {
+ struct list_head list;
+ struct pci_dev *pdev;
+ struct net_device *ndev;
+ struct ntb_transport_qp *qp;
+};
+
+#define NTB_TX_TIMEOUT_MS 1000
+#define NTB_RXQ_SIZE 100
+
+static LIST_HEAD(dev_list);
+
+static void ntb_netdev_event_handler(void *data, int status)
+{
+ struct net_device *ndev = data;
+ struct ntb_netdev *dev = netdev_priv(ndev);
+
+ netdev_dbg(ndev, "Event %x, Link %x\n", status,
+ ntb_transport_link_query(dev->qp));
+
+ /* Currently, only link status event is supported */
+ if (status)
+ netif_carrier_on(ndev);
+ else
+ netif_carrier_off(ndev);
+}
+
+static void ntb_netdev_rx_handler(struct ntb_transport_qp *qp, void *qp_data,
+ void *data, int len)
+{
+ struct net_device *ndev = qp_data;
+ struct sk_buff *skb;
+ int rc;
+
+ skb = data;
+ if (!skb)
+ return;
+
+ netdev_dbg(ndev, "%s: %d byte payload received\n", __func__, len);
+
+ skb_put(skb, len);
+ skb->protocol = eth_type_trans(skb, ndev);
+ skb->ip_summed = CHECKSUM_NONE;
+
+ if (netif_rx(skb) == NET_RX_DROP) {
+ ndev->stats.rx_errors++;
+ ndev->stats.rx_dropped++;
+ } else {
+ ndev->stats.rx_packets++;
+ ndev->stats.rx_bytes += len;
+ }
+
+ skb = netdev_alloc_skb(ndev, ndev->mtu + ETH_HLEN);
+ if (!skb) {
+ ndev->stats.rx_errors++;
+ ndev->stats.rx_frame_errors++;
+ return;
+ }
+
+ rc = ntb_transport_rx_enqueue(qp, skb, skb->data, ndev->mtu + ETH_HLEN);
+ if (rc) {
+ ndev->stats.rx_errors++;
+ ndev->stats.rx_fifo_errors++;
+ }
+}
+
+static void ntb_netdev_tx_handler(struct ntb_transport_qp *qp, void *qp_data,
+ void *data, int len)
+{
+ struct net_device *ndev = qp_data;
+ struct sk_buff *skb;
+
+ skb = data;
+ if (!skb || !ndev)
+ return;
+
+ if (len > 0) {
+ ndev->stats.tx_packets++;
+ ndev->stats.tx_bytes += skb->len;
+ } else {
+ ndev->stats.tx_errors++;
+ ndev->stats.tx_aborted_errors++;
+ }
+
+ dev_kfree_skb(skb);
+
+ if (netif_queue_stopped(ndev))
+ netif_wake_queue(ndev);
+}
+
+static netdev_tx_t ntb_netdev_start_xmit(struct sk_buff *skb,
+ struct net_device *ndev)
+{
+ struct ntb_netdev *dev = netdev_priv(ndev);
+ int rc;
+
+ netdev_dbg(ndev, "ntb_transport_tx_enqueue\n");
+
+ rc = ntb_transport_tx_enqueue(dev->qp, skb, skb->data, skb->len);
+ if (rc)
+ goto err;
+
+ return NETDEV_TX_OK;
+
+err:
+ ndev->stats.tx_dropped++;
+ ndev->stats.tx_errors++;
+ netif_stop_queue(ndev);
+ return NETDEV_TX_BUSY;
+}
+
+static int ntb_netdev_open(struct net_device *ndev)
+{
+ struct ntb_netdev *dev = netdev_priv(ndev);
+ struct sk_buff *skb;
+ int rc, i, len;
+
+ /* Add some empty rx bufs */
+ for (i = 0; i < NTB_RXQ_SIZE; i++) {
+ skb = netdev_alloc_skb(ndev, ndev->mtu + ETH_HLEN);
+ if (!skb) {
+ rc = -ENOMEM;
+ goto err;
+ }
+
+ rc = ntb_transport_rx_enqueue(dev->qp, skb, skb->data,
+ ndev->mtu + ETH_HLEN);
+ if (rc == -EINVAL)
+ goto err;
+ }
+
+ netif_carrier_off(ndev);
+ ntb_transport_link_up(dev->qp);
+
+ return 0;
+
+err:
+ while ((skb = ntb_transport_rx_remove(dev->qp, &len)))
+ dev_kfree_skb(skb);
+ return rc;
+}
+
+static int ntb_netdev_close(struct net_device *ndev)
+{
+ struct ntb_netdev *dev = netdev_priv(ndev);
+ struct sk_buff *skb;
+ int len;
+
+ ntb_transport_link_down(dev->qp);
+
+ while ((skb = ntb_transport_rx_remove(dev->qp, &len)))
+ dev_kfree_skb(skb);
+
+ return 0;
+}
+
+static int ntb_netdev_change_mtu(struct net_device *ndev, int new_mtu)
+{
+ struct ntb_netdev *dev = netdev_priv(ndev);
+ struct sk_buff *skb;
+ int len, rc;
+
+ if (new_mtu > ntb_transport_max_size(dev->qp) - ETH_HLEN)
+ return -EINVAL;
+
+ if (!netif_running(ndev)) {
+ ndev->mtu = new_mtu;
+ return 0;
+ }
+
+ /* Bring down the link and dispose of posted rx entries */
+ ntb_transport_link_down(dev->qp);
+
+ if (ndev->mtu < new_mtu) {
+ int i;
+
+ for (i = 0; (skb = ntb_transport_rx_remove(dev->qp, &len)); i++)
+ dev_kfree_skb(skb);
+
+ for (; i; i--) {
+ skb = netdev_alloc_skb(ndev, new_mtu + ETH_HLEN);
+ if (!skb) {
+ rc = -ENOMEM;
+ goto err;
+ }
+
+ rc = ntb_transport_rx_enqueue(dev->qp, skb, skb->data,
+ new_mtu + ETH_HLEN);
+ if (rc) {
+ dev_kfree_skb(skb);
+ goto err;
+ }
+ }
+ }
+
+ ndev->mtu = new_mtu;
+
+ ntb_transport_link_up(dev->qp);
+
+ return 0;
+
+err:
+ ntb_transport_link_down(dev->qp);
+
+ while ((skb = ntb_transport_rx_remove(dev->qp, &len)))
+ dev_kfree_skb(skb);
+
+ netdev_err(ndev, "Error changing MTU, device inoperable\n");
+ return rc;
+}
+
+static void ntb_netdev_tx_timeout(struct net_device *ndev)
+{
+ if (netif_running(ndev))
+ netif_wake_queue(ndev);
+}
+
+static const struct net_device_ops ntb_netdev_ops = {
+ .ndo_open = ntb_netdev_open,
+ .ndo_stop = ntb_netdev_close,
+ .ndo_start_xmit = ntb_netdev_start_xmit,
+ .ndo_change_mtu = ntb_netdev_change_mtu,
+ .ndo_tx_timeout = ntb_netdev_tx_timeout,
+ .ndo_set_mac_address = eth_mac_addr,
+};
+
+static void ntb_get_drvinfo(struct net_device *ndev,
+ struct ethtool_drvinfo *info)
+{
+ struct ntb_netdev *dev = netdev_priv(ndev);
+
+ strlcpy(info->driver, KBUILD_MODNAME, sizeof(info->driver));
+ strlcpy(info->version, NTB_NETDEV_VER, sizeof(info->version));
+ strlcpy(info->bus_info, pci_name(dev->pdev), sizeof(info->bus_info));
+}
+
+static int ntb_get_settings(struct net_device *dev, struct ethtool_cmd *cmd)
+{
+ cmd->supported = SUPPORTED_Backplane;
+ cmd->advertising = ADVERTISED_Backplane;
+ cmd->speed = SPEED_UNKNOWN;
+ ethtool_cmd_speed_set(cmd, SPEED_UNKNOWN);
+ cmd->duplex = DUPLEX_FULL;
+ cmd->port = PORT_OTHER;
+ cmd->phy_address = 0;
+ cmd->transceiver = XCVR_DUMMY1;
+ cmd->autoneg = AUTONEG_ENABLE;
+ cmd->maxtxpkt = 0;
+ cmd->maxrxpkt = 0;
+
+ return 0;
+}
+
+static const struct ethtool_ops ntb_ethtool_ops = {
+ .get_drvinfo = ntb_get_drvinfo,
+ .get_link = ethtool_op_get_link,
+ .get_settings = ntb_get_settings,
+};
+
+static const struct ntb_queue_handlers ntb_netdev_handlers = {
+ .tx_handler = ntb_netdev_tx_handler,
+ .rx_handler = ntb_netdev_rx_handler,
+ .event_handler = ntb_netdev_event_handler,
+};
+
+static int __devinit ntb_netdev_probe(struct pci_dev *pdev)
+{
+ struct net_device *ndev;
+ struct ntb_netdev *dev;
+ int rc;
+
+ ndev = alloc_etherdev(sizeof(struct ntb_netdev));
+ if (!ndev)
+ return -ENOMEM;
+
+ dev = netdev_priv(ndev);
+ dev->ndev = ndev;
+ dev->pdev = pdev;
+ BUG_ON(!dev->pdev);
+ ndev->features = NETIF_F_HIGHDMA;
+
+ ndev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
+
+ ndev->hw_features = ndev->features;
+ ndev->watchdog_timeo = msecs_to_jiffies(NTB_TX_TIMEOUT_MS);
+
+ random_ether_addr(ndev->perm_addr);
+ memcpy(ndev->dev_addr, ndev->perm_addr, ndev->addr_len);
+
+ ndev->netdev_ops = &ntb_netdev_ops;
+ SET_ETHTOOL_OPS(ndev, &ntb_ethtool_ops);
+
+ dev->qp = ntb_transport_create_queue(ndev, pdev, &ntb_netdev_handlers);
+ if (!dev->qp) {
+ rc = -EIO;
+ goto err;
+ }
+
+ ndev->mtu = ntb_transport_max_size(dev->qp) - ETH_HLEN;
+
+ rc = register_netdev(ndev);
+ if (rc)
+ goto err1;
+
+ list_add(&dev->list, &dev_list);
+ pr_info("%s: %s created\n", KBUILD_MODNAME, ndev->name);
+ return 0;
+
+err1:
+ ntb_transport_free_queue(dev->qp);
+err:
+ free_netdev(ndev);
+ return rc;
+}
+
+static void __exit ntb_netdev_remove(struct pci_dev *pdev)
+{
+ struct net_device *ndev;
+ struct ntb_netdev *dev;
+
+ list_for_each_entry(dev, &dev_list, list) {
+ if (dev->pdev == pdev)
+ break;
+ }
+ if (dev == NULL)
+ return;
+
+ ndev = dev->ndev;
+
+ unregister_netdev(ndev);
+ ntb_transport_free_queue(dev->qp);
+ free_netdev(ndev);
+}
+
+static struct ntb_client ntb_netdev_client = {
+ .driver.name = KBUILD_MODNAME,
+ .driver.owner = THIS_MODULE,
+ .probe = ntb_netdev_probe,
+ .remove = ntb_netdev_remove,
+};
+
+static int __init ntb_netdev_init_module(void)
+{
+ return ntb_register_client(&ntb_netdev_client);
+}
+
+module_init(ntb_netdev_init_module);
+
+static void __exit ntb_netdev_exit_module(void)
+{
+ ntb_unregister_client(&ntb_netdev_client);
+ pr_info("%s: Driver removed\n", KBUILD_MODNAME);
+}
+
+module_exit(ntb_netdev_exit_module);
--
1.7.9.5