/* * 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 list_head list; 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 LIST_HEAD(dev_list); 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(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(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 + msecs_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); 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_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); random_ether_addr(ndev->perm_addr); memcpy(ndev->dev_addr, ndev->perm_addr, ndev->addr_len); 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; list_add(&dev->list, &dev_list); 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 ntb_dev *ntb; struct net_device *ndev; struct pci_dev *pdev; struct ntb_netdev *dev; bool found = false; ntb = dev_ntb(client_dev->parent); pdev = ntb->pdev; list_for_each_entry(dev, &dev_list, list) { if (dev->pdev == pdev) { found = true; break; } } if (!found) return; list_del(&dev->list); ndev = dev->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; return ntb_transport_register_client(&ntb_netdev_client); } module_init(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);