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Diffstat (limited to 'drivers/net/ntb_netdev.c')
-rw-r--r--drivers/net/ntb_netdev.c503
1 files changed, 503 insertions, 0 deletions
diff --git a/drivers/net/ntb_netdev.c b/drivers/net/ntb_netdev.c
new file mode 100644
index 0000000000..536bd6564f
--- /dev/null
+++ b/drivers/net/ntb_netdev.c
@@ -0,0 +1,503 @@
+/*
+ * 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.
+ * Copyright (C) 2015 EMC 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.
+ * Copyright (C) 2015 EMC 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.
+ *
+ * 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>
+#include <linux/ntb_transport.h>
+
+#define NTB_NETDEV_VER "0.7"
+
+MODULE_DESCRIPTION(KBUILD_MODNAME);
+MODULE_VERSION(NTB_NETDEV_VER);
+MODULE_LICENSE("Dual BSD/GPL");
+MODULE_AUTHOR("Intel Corporation");
+
+/* Time in usecs for tx resource reaper */
+static unsigned int tx_time = 1;
+
+/* Number of descriptors to free before resuming tx */
+static unsigned int tx_start = 10;
+
+/* Number of descriptors still available before stop upper layer tx */
+static unsigned int tx_stop = 5;
+
+struct ntb_netdev {
+ struct pci_dev *pdev;
+ struct net_device *ndev;
+ struct ntb_transport_qp *qp;
+ struct timer_list tx_timer;
+};
+
+#define NTB_TX_TIMEOUT_MS 1000
+#define NTB_RXQ_SIZE 100
+
+static void ntb_netdev_event_handler(void *data, int link_is_up)
+{
+ struct net_device *ndev = data;
+ struct ntb_netdev *dev = netdev_priv(ndev);
+
+ netdev_dbg(ndev, "Event %x, Link %x\n", link_is_up,
+ ntb_transport_link_query(dev->qp));
+
+ if (link_is_up) {
+ if (ntb_transport_link_query(dev->qp))
+ 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);
+
+ if (len < 0) {
+ ndev->stats.rx_errors++;
+ ndev->stats.rx_length_errors++;
+ goto enqueue_again;
+ }
+
+ 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;
+ }
+
+enqueue_again:
+ rc = ntb_transport_rx_enqueue(qp, skb, skb->data, ndev->mtu + ETH_HLEN);
+ if (rc) {
+ dev_kfree_skb_any(skb);
+ ndev->stats.rx_errors++;
+ ndev->stats.rx_fifo_errors++;
+ }
+}
+
+static int __ntb_netdev_maybe_stop_tx(struct net_device *netdev,
+ struct ntb_transport_qp *qp, int size)
+{
+ struct ntb_netdev *dev = netdev_priv(netdev);
+
+ netif_stop_queue(netdev);
+ /* Make sure to see the latest value of ntb_transport_tx_free_entry()
+ * since the queue was last started.
+ */
+ smp_mb();
+
+ if (likely(ntb_transport_tx_free_entry(qp) < size)) {
+ mod_timer(&dev->tx_timer, jiffies + usecs_to_jiffies(tx_time));
+ return -EBUSY;
+ }
+
+ netif_start_queue(netdev);
+ return 0;
+}
+
+static int ntb_netdev_maybe_stop_tx(struct net_device *ndev,
+ struct ntb_transport_qp *qp, int size)
+{
+ if (netif_queue_stopped(ndev) ||
+ (ntb_transport_tx_free_entry(qp) >= size))
+ return 0;
+
+ return __ntb_netdev_maybe_stop_tx(ndev, qp, size);
+}
+
+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;
+ struct ntb_netdev *dev = netdev_priv(ndev);
+
+ 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_any(skb);
+
+ if (ntb_transport_tx_free_entry(dev->qp) >= tx_start) {
+ /* Make sure anybody stopping the queue after this sees the new
+ * value of ntb_transport_tx_free_entry()
+ */
+ smp_mb();
+ 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;
+
+ ntb_netdev_maybe_stop_tx(ndev, dev->qp, tx_stop);
+
+ rc = ntb_transport_tx_enqueue(dev->qp, skb, skb->data, skb->len);
+ if (rc)
+ goto err;
+
+ /* check for next submit */
+ ntb_netdev_maybe_stop_tx(ndev, dev->qp, tx_stop);
+
+ return NETDEV_TX_OK;
+
+err:
+ ndev->stats.tx_dropped++;
+ ndev->stats.tx_errors++;
+ return NETDEV_TX_BUSY;
+}
+
+static void ntb_netdev_tx_timer(struct timer_list *t)
+{
+ struct ntb_netdev *dev = from_timer(dev, t, tx_timer);
+ struct net_device *ndev = dev->ndev;
+
+ if (ntb_transport_tx_free_entry(dev->qp) < tx_stop) {
+ mod_timer(&dev->tx_timer, jiffies + usecs_to_jiffies(tx_time));
+ } else {
+ /* Make sure anybody stopping the queue after this sees the new
+ * value of ntb_transport_tx_free_entry()
+ */
+ smp_mb();
+ if (netif_queue_stopped(ndev))
+ netif_wake_queue(ndev);
+ }
+}
+
+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) {
+ dev_kfree_skb(skb);
+ goto err;
+ }
+ }
+
+ timer_setup(&dev->tx_timer, ntb_netdev_tx_timer, 0);
+
+ netif_carrier_off(ndev);
+ ntb_transport_link_up(dev->qp);
+ netif_start_queue(ndev);
+
+ 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);
+
+ del_timer_sync(&dev->tx_timer);
+
+ 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 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_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);
+
+ strscpy(info->driver, KBUILD_MODNAME, sizeof(info->driver));
+ strscpy(info->version, NTB_NETDEV_VER, sizeof(info->version));
+ strscpy(info->bus_info, pci_name(dev->pdev), sizeof(info->bus_info));
+}
+
+static int ntb_get_link_ksettings(struct net_device *dev,
+ struct ethtool_link_ksettings *cmd)
+{
+ ethtool_link_ksettings_zero_link_mode(cmd, supported);
+ ethtool_link_ksettings_add_link_mode(cmd, supported, Backplane);
+ ethtool_link_ksettings_zero_link_mode(cmd, advertising);
+ ethtool_link_ksettings_add_link_mode(cmd, advertising, Backplane);
+
+ cmd->base.speed = SPEED_UNKNOWN;
+ cmd->base.duplex = DUPLEX_FULL;
+ cmd->base.port = PORT_OTHER;
+ cmd->base.phy_address = 0;
+ cmd->base.autoneg = AUTONEG_ENABLE;
+
+ return 0;
+}
+
+static const struct ethtool_ops ntb_ethtool_ops = {
+ .get_drvinfo = ntb_get_drvinfo,
+ .get_link = ethtool_op_get_link,
+ .get_link_ksettings = ntb_get_link_ksettings,
+};
+
+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 ntb_netdev_probe(struct device *client_dev)
+{
+ struct ntb_dev *ntb;
+ struct net_device *ndev;
+ struct pci_dev *pdev;
+ struct ntb_netdev *dev;
+ int rc;
+
+ ntb = dev_ntb(client_dev->parent);
+ pdev = ntb->pdev;
+ if (!pdev)
+ return -ENODEV;
+
+ ndev = alloc_etherdev(sizeof(*dev));
+ if (!ndev)
+ return -ENOMEM;
+
+ SET_NETDEV_DEV(ndev, client_dev);
+
+ dev = netdev_priv(ndev);
+ dev->ndev = ndev;
+ dev->pdev = 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);
+
+ eth_random_addr(ndev->perm_addr);
+ dev_addr_set(ndev, ndev->perm_addr);
+
+ ndev->netdev_ops = &ntb_netdev_ops;
+ ndev->ethtool_ops = &ntb_ethtool_ops;
+
+ ndev->min_mtu = 0;
+ ndev->max_mtu = ETH_MAX_MTU;
+
+ dev->qp = ntb_transport_create_queue(ndev, client_dev,
+ &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;
+
+ dev_set_drvdata(client_dev, ndev);
+ dev_info(&pdev->dev, "%s created\n", ndev->name);
+ return 0;
+
+err1:
+ ntb_transport_free_queue(dev->qp);
+err:
+ free_netdev(ndev);
+ return rc;
+}
+
+static void ntb_netdev_remove(struct device *client_dev)
+{
+ struct net_device *ndev = dev_get_drvdata(client_dev);
+ struct ntb_netdev *dev = netdev_priv(ndev);
+
+ unregister_netdev(ndev);
+ ntb_transport_free_queue(dev->qp);
+ free_netdev(ndev);
+}
+
+static struct ntb_transport_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)
+{
+ int rc;
+
+ rc = ntb_transport_register_client_dev(KBUILD_MODNAME);
+ if (rc)
+ return rc;
+
+ rc = ntb_transport_register_client(&ntb_netdev_client);
+ if (rc) {
+ ntb_transport_unregister_client_dev(KBUILD_MODNAME);
+ return rc;
+ }
+
+ return 0;
+}
+late_initcall(ntb_netdev_init_module);
+
+static void __exit ntb_netdev_exit_module(void)
+{
+ ntb_transport_unregister_client(&ntb_netdev_client);
+ ntb_transport_unregister_client_dev(KBUILD_MODNAME);
+}
+module_exit(ntb_netdev_exit_module);