drivers/net/ntb_netdev.c

   1 /*
   2  * This file is provided under a dual BSD/GPLv2 license.  When using or
   3  *   redistributing this file, you may do so under either license.
   4  *
   5  *   GPL LICENSE SUMMARY
   6  *
   7  *   Copyright(c) 2012 Intel Corporation. All rights reserved.
   8  *   Copyright (C) 2015 EMC Corporation. All Rights Reserved.
   9  *
  10  *   This program is free software; you can redistribute it and/or modify
  11  *   it under the terms of version 2 of the GNU General Public License as
  12  *   published by the Free Software Foundation.
  13  *
  14  *   BSD LICENSE
  15  *
  16  *   Copyright(c) 2012 Intel Corporation. All rights reserved.
  17  *   Copyright (C) 2015 EMC Corporation. All Rights Reserved.
  18  *
  19  *   Redistribution and use in source and binary forms, with or without
  20  *   modification, are permitted provided that the following conditions
  21  *   are met:
  22  *
  23  *     * Redistributions of source code must retain the above copyright
  24  *       notice, this list of conditions and the following disclaimer.
  25  *     * Redistributions in binary form must reproduce the above copy
  26  *       notice, this list of conditions and the following disclaimer in
  27  *       the documentation and/or other materials provided with the
  28  *       distribution.
  29  *     * Neither the name of Intel Corporation nor the names of its
  30  *       contributors may be used to endorse or promote products derived
  31  *       from this software without specific prior written permission.
  32  *
  33  *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  34  *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  35  *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  36  *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  37  *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  38  *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  39  *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  40  *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  41  *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  42  *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  43  *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  44  *
  45  * PCIe NTB Network Linux driver
  46  *
  47  * Contact Information:
  48  * Jon Mason <jon.mason@intel.com>
  49  */
  50 #include <linux/etherdevice.h>
  51 #include <linux/ethtool.h>
  52 #include <linux/module.h>
  53 #include <linux/pci.h>
  54 #include <linux/ntb.h>
  55 #include <linux/ntb_transport.h>
  56
  57 #define NTB_NETDEV_VER  "0.7"
  58
  59 MODULE_DESCRIPTION(KBUILD_MODNAME);
  60 MODULE_VERSION(NTB_NETDEV_VER);
  61 MODULE_LICENSE("Dual BSD/GPL");
  62 MODULE_AUTHOR("Intel Corporation");
  63
  64 struct ntb_netdev {
  65         struct list_head list;
  66         struct pci_dev *pdev;
  67         struct net_device *ndev;
  68         struct ntb_transport_qp *qp;
  69 };
  70
  71 #define NTB_TX_TIMEOUT_MS       1000
  72 #define NTB_RXQ_SIZE            100
  73
  74 static LIST_HEAD(dev_list);
  75
  76 static void ntb_netdev_event_handler(void *data, int link_is_up)
  77 {
  78         struct net_device *ndev = data;
  79         struct ntb_netdev *dev = netdev_priv(ndev);
  80
  81         netdev_dbg(ndev, "Event %x, Link %x\n", link_is_up,
  82                    ntb_transport_link_query(dev->qp));
  83
  84         if (link_is_up) {
  85                 if (ntb_transport_link_query(dev->qp))
  86                         netif_carrier_on(ndev);
  87         } else {
  88                 netif_carrier_off(ndev);
  89         }
  90 }
  91
  92 static void ntb_netdev_rx_handler(struct ntb_transport_qp *qp, void *qp_data,
  93                                   void *data, int len)
  94 {
  95         struct net_device *ndev = qp_data;
  96         struct sk_buff *skb;
  97         int rc;
  98
  99         skb = data;
 100         if (!skb)
 101                 return;
 102
 103         netdev_dbg(ndev, "%s: %d byte payload received\n", __func__, len);
 104
 105         skb_put(skb, len);
 106         skb->protocol = eth_type_trans(skb, ndev);
 107         skb->ip_summed = CHECKSUM_NONE;
 108
 109         if (netif_rx(skb) == NET_RX_DROP) {
 110                 ndev->stats.rx_errors++;
 111                 ndev->stats.rx_dropped++;
 112         } else {
 113                 ndev->stats.rx_packets++;
 114                 ndev->stats.rx_bytes += len;
 115         }
 116
 117         skb = netdev_alloc_skb(ndev, ndev->mtu + ETH_HLEN);
 118         if (!skb) {
 119                 ndev->stats.rx_errors++;
 120                 ndev->stats.rx_frame_errors++;
 121                 return;
 122         }
 123
 124         rc = ntb_transport_rx_enqueue(qp, skb, skb->data, ndev->mtu + ETH_HLEN);
 125         if (rc) {
 126                 dev_kfree_skb(skb);
 127                 ndev->stats.rx_errors++;
 128                 ndev->stats.rx_fifo_errors++;
 129         }
 130 }
 131
 132 static void ntb_netdev_tx_handler(struct ntb_transport_qp *qp, void *qp_data,
 133                                   void *data, int len)
 134 {
 135         struct net_device *ndev = qp_data;
 136         struct sk_buff *skb;
 137
 138         skb = data;
 139         if (!skb || !ndev)
 140                 return;
 141
 142         if (len > 0) {
 143                 ndev->stats.tx_packets++;
 144                 ndev->stats.tx_bytes += skb->len;
 145         } else {
 146                 ndev->stats.tx_errors++;
 147                 ndev->stats.tx_aborted_errors++;
 148         }
 149
 150         dev_kfree_skb(skb);
 151 }
 152
 153 static netdev_tx_t ntb_netdev_start_xmit(struct sk_buff *skb,
 154                                          struct net_device *ndev)
 155 {
 156         struct ntb_netdev *dev = netdev_priv(ndev);
 157         int rc;
 158
 159         rc = ntb_transport_tx_enqueue(dev->qp, skb, skb->data, skb->len);
 160         if (rc)
 161                 goto err;
 162
 163         return NETDEV_TX_OK;
 164
 165 err:
 166         ndev->stats.tx_dropped++;
 167         ndev->stats.tx_errors++;
 168         return NETDEV_TX_BUSY;
 169 }
 170
 171 static int ntb_netdev_open(struct net_device *ndev)
 172 {
 173         struct ntb_netdev *dev = netdev_priv(ndev);
 174         struct sk_buff *skb;
 175         int rc, i, len;
 176
 177         /* Add some empty rx bufs */
 178         for (i = 0; i < NTB_RXQ_SIZE; i++) {
 179                 skb = netdev_alloc_skb(ndev, ndev->mtu + ETH_HLEN);
 180                 if (!skb) {
 181                         rc = -ENOMEM;
 182                         goto err;
 183                 }
 184
 185                 rc = ntb_transport_rx_enqueue(dev->qp, skb, skb->data,
 186                                               ndev->mtu + ETH_HLEN);
 187                 if (rc == -EINVAL) {
 188                         dev_kfree_skb(skb);
 189                         goto err;
 190                 }
 191         }
 192
 193         netif_carrier_off(ndev);
 194         ntb_transport_link_up(dev->qp);
 195
 196         return 0;
 197
 198 err:
 199         while ((skb = ntb_transport_rx_remove(dev->qp, &len)))
 200                 dev_kfree_skb(skb);
 201         return rc;
 202 }
 203
 204 static int ntb_netdev_close(struct net_device *ndev)
 205 {
 206         struct ntb_netdev *dev = netdev_priv(ndev);
 207         struct sk_buff *skb;
 208         int len;
 209
 210         ntb_transport_link_down(dev->qp);
 211
 212         while ((skb = ntb_transport_rx_remove(dev->qp, &len)))
 213                 dev_kfree_skb(skb);
 214
 215         return 0;
 216 }
 217
 218 static int ntb_netdev_change_mtu(struct net_device *ndev, int new_mtu)
 219 {
 220         struct ntb_netdev *dev = netdev_priv(ndev);
 221         struct sk_buff *skb;
 222         int len, rc;
 223
 224         if (new_mtu > ntb_transport_max_size(dev->qp) - ETH_HLEN)
 225                 return -EINVAL;
 226
 227         if (!netif_running(ndev)) {
 228                 ndev->mtu = new_mtu;
 229                 return 0;
 230         }
 231
 232         /* Bring down the link and dispose of posted rx entries */
 233         ntb_transport_link_down(dev->qp);
 234
 235         if (ndev->mtu < new_mtu) {
 236                 int i;
 237
 238                 for (i = 0; (skb = ntb_transport_rx_remove(dev->qp, &len)); i++)
 239                         dev_kfree_skb(skb);
 240
 241                 for (; i; i--) {
 242                         skb = netdev_alloc_skb(ndev, new_mtu + ETH_HLEN);
 243                         if (!skb) {
 244                                 rc = -ENOMEM;
 245                                 goto err;
 246                         }
 247
 248                         rc = ntb_transport_rx_enqueue(dev->qp, skb, skb->data,
 249                                                       new_mtu + ETH_HLEN);
 250                         if (rc) {
 251                                 dev_kfree_skb(skb);
 252                                 goto err;
 253                         }
 254                 }
 255         }
 256
 257         ndev->mtu = new_mtu;
 258
 259         ntb_transport_link_up(dev->qp);
 260
 261         return 0;
 262
 263 err:
 264         ntb_transport_link_down(dev->qp);
 265
 266         while ((skb = ntb_transport_rx_remove(dev->qp, &len)))
 267                 dev_kfree_skb(skb);
 268
 269         netdev_err(ndev, "Error changing MTU, device inoperable\n");
 270         return rc;
 271 }
 272
 273 static const struct net_device_ops ntb_netdev_ops = {
 274         .ndo_open = ntb_netdev_open,
 275         .ndo_stop = ntb_netdev_close,
 276         .ndo_start_xmit = ntb_netdev_start_xmit,
 277         .ndo_change_mtu = ntb_netdev_change_mtu,
 278         .ndo_set_mac_address = eth_mac_addr,
 279 };
 280
 281 static void ntb_get_drvinfo(struct net_device *ndev,
 282                             struct ethtool_drvinfo *info)
 283 {
 284         struct ntb_netdev *dev = netdev_priv(ndev);
 285
 286         strlcpy(info->driver, KBUILD_MODNAME, sizeof(info->driver));
 287         strlcpy(info->version, NTB_NETDEV_VER, sizeof(info->version));
 288         strlcpy(info->bus_info, pci_name(dev->pdev), sizeof(info->bus_info));
 289 }
 290
 291 static int ntb_get_settings(struct net_device *dev, struct ethtool_cmd *cmd)
 292 {
 293         cmd->supported = SUPPORTED_Backplane;
 294         cmd->advertising = ADVERTISED_Backplane;
 295         ethtool_cmd_speed_set(cmd, SPEED_UNKNOWN);
 296         cmd->duplex = DUPLEX_FULL;
 297         cmd->port = PORT_OTHER;
 298         cmd->phy_address = 0;
 299         cmd->transceiver = XCVR_DUMMY1;
 300         cmd->autoneg = AUTONEG_ENABLE;
 301         cmd->maxtxpkt = 0;
 302         cmd->maxrxpkt = 0;
 303
 304         return 0;
 305 }
 306
 307 static const struct ethtool_ops ntb_ethtool_ops = {
 308         .get_drvinfo = ntb_get_drvinfo,
 309         .get_link = ethtool_op_get_link,
 310         .get_settings = ntb_get_settings,
 311 };
 312
 313 static const struct ntb_queue_handlers ntb_netdev_handlers = {
 314         .tx_handler = ntb_netdev_tx_handler,
 315         .rx_handler = ntb_netdev_rx_handler,
 316         .event_handler = ntb_netdev_event_handler,
 317 };
 318
 319 static int ntb_netdev_probe(struct device *client_dev)
 320 {
 321         struct ntb_dev *ntb;
 322         struct net_device *ndev;
 323         struct pci_dev *pdev;
 324         struct ntb_netdev *dev;
 325         int rc;
 326
 327         ntb = dev_ntb(client_dev->parent);
 328         pdev = ntb->pdev;
 329         if (!pdev)
 330                 return -ENODEV;
 331
 332         ndev = alloc_etherdev(sizeof(*dev));
 333         if (!ndev)
 334                 return -ENOMEM;
 335
 336         dev = netdev_priv(ndev);
 337         dev->ndev = ndev;
 338         dev->pdev = pdev;
 339         ndev->features = NETIF_F_HIGHDMA;
 340
 341         ndev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
 342
 343         ndev->hw_features = ndev->features;
 344         ndev->watchdog_timeo = msecs_to_jiffies(NTB_TX_TIMEOUT_MS);
 345
 346         random_ether_addr(ndev->perm_addr);
 347         memcpy(ndev->dev_addr, ndev->perm_addr, ndev->addr_len);
 348
 349         ndev->netdev_ops = &ntb_netdev_ops;
 350         ndev->ethtool_ops = &ntb_ethtool_ops;
 351
 352         dev->qp = ntb_transport_create_queue(ndev, client_dev,
 353                                              &ntb_netdev_handlers);
 354         if (!dev->qp) {
 355                 rc = -EIO;
 356                 goto err;
 357         }
 358
 359         ndev->mtu = ntb_transport_max_size(dev->qp) - ETH_HLEN;
 360
 361         rc = register_netdev(ndev);
 362         if (rc)
 363                 goto err1;
 364
 365         list_add(&dev->list, &dev_list);
 366         dev_info(&pdev->dev, "%s created\n", ndev->name);
 367         return 0;
 368
 369 err1:
 370         ntb_transport_free_queue(dev->qp);
 371 err:
 372         free_netdev(ndev);
 373         return rc;
 374 }
 375
 376 static void ntb_netdev_remove(struct device *client_dev)
 377 {
 378         struct ntb_dev *ntb;
 379         struct net_device *ndev;
 380         struct pci_dev *pdev;
 381         struct ntb_netdev *dev;
 382         bool found = false;
 383
 384         ntb = dev_ntb(client_dev->parent);
 385         pdev = ntb->pdev;
 386
 387         list_for_each_entry(dev, &dev_list, list) {
 388                 if (dev->pdev == pdev) {
 389                         found = true;
 390                         break;
 391                 }
 392         }
 393         if (!found)
 394                 return;
 395
 396         list_del(&dev->list);
 397
 398         ndev = dev->ndev;
 399
 400         unregister_netdev(ndev);
 401         ntb_transport_free_queue(dev->qp);
 402         free_netdev(ndev);
 403 }
 404
 405 static struct ntb_transport_client ntb_netdev_client = {
 406         .driver.name = KBUILD_MODNAME,
 407         .driver.owner = THIS_MODULE,
 408         .probe = ntb_netdev_probe,
 409         .remove = ntb_netdev_remove,
 410 };
 411
 412 static int __init ntb_netdev_init_module(void)
 413 {
 414         int rc;
 415
 416         rc = ntb_transport_register_client_dev(KBUILD_MODNAME);
 417         if (rc)
 418                 return rc;
 419         return ntb_transport_register_client(&ntb_netdev_client);
 420 }
 421 module_init(ntb_netdev_init_module);
 422
 423 static void __exit ntb_netdev_exit_module(void)
 424 {
 425         ntb_transport_unregister_client(&ntb_netdev_client);
 426         ntb_transport_unregister_client_dev(KBUILD_MODNAME);
 427 }
 428 module_exit(ntb_netdev_exit_module);