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         if (len < 0) {
 106                 ndev->stats.rx_errors++;
 107                 ndev->stats.rx_length_errors++;
 108                 goto enqueue_again;
 109         }
 110
 111         skb_put(skb, len);
 112         skb->protocol = eth_type_trans(skb, ndev);
 113         skb->ip_summed = CHECKSUM_NONE;
 114
 115         if (netif_rx(skb) == NET_RX_DROP) {
 116                 ndev->stats.rx_errors++;
 117                 ndev->stats.rx_dropped++;
 118         } else {
 119                 ndev->stats.rx_packets++;
 120                 ndev->stats.rx_bytes += len;
 121         }
 122
 123         skb = netdev_alloc_skb(ndev, ndev->mtu + ETH_HLEN);
 124         if (!skb) {
 125                 ndev->stats.rx_errors++;
 126                 ndev->stats.rx_frame_errors++;
 127                 return;
 128         }
 129
 130 enqueue_again:
 131         rc = ntb_transport_rx_enqueue(qp, skb, skb->data, ndev->mtu + ETH_HLEN);
 132         if (rc) {
 133                 dev_kfree_skb(skb);
 134                 ndev->stats.rx_errors++;
 135                 ndev->stats.rx_fifo_errors++;
 136         }
 137 }
 138
 139 static void ntb_netdev_tx_handler(struct ntb_transport_qp *qp, void *qp_data,
 140                                   void *data, int len)
 141 {
 142         struct net_device *ndev = qp_data;
 143         struct sk_buff *skb;
 144
 145         skb = data;
 146         if (!skb || !ndev)
 147                 return;
 148
 149         if (len > 0) {
 150                 ndev->stats.tx_packets++;
 151                 ndev->stats.tx_bytes += skb->len;
 152         } else {
 153                 ndev->stats.tx_errors++;
 154                 ndev->stats.tx_aborted_errors++;
 155         }
 156
 157         dev_kfree_skb(skb);
 158 }
 159
 160 static netdev_tx_t ntb_netdev_start_xmit(struct sk_buff *skb,
 161                                          struct net_device *ndev)
 162 {
 163         struct ntb_netdev *dev = netdev_priv(ndev);
 164         int rc;
 165
 166         rc = ntb_transport_tx_enqueue(dev->qp, skb, skb->data, skb->len);
 167         if (rc)
 168                 goto err;
 169
 170         return NETDEV_TX_OK;
 171
 172 err:
 173         ndev->stats.tx_dropped++;
 174         ndev->stats.tx_errors++;
 175         return NETDEV_TX_BUSY;
 176 }
 177
 178 static int ntb_netdev_open(struct net_device *ndev)
 179 {
 180         struct ntb_netdev *dev = netdev_priv(ndev);
 181         struct sk_buff *skb;
 182         int rc, i, len;
 183
 184         /* Add some empty rx bufs */
 185         for (i = 0; i < NTB_RXQ_SIZE; i++) {
 186                 skb = netdev_alloc_skb(ndev, ndev->mtu + ETH_HLEN);
 187                 if (!skb) {
 188                         rc = -ENOMEM;
 189                         goto err;
 190                 }
 191
 192                 rc = ntb_transport_rx_enqueue(dev->qp, skb, skb->data,
 193                                               ndev->mtu + ETH_HLEN);
 194                 if (rc) {
 195                         dev_kfree_skb(skb);
 196                         goto err;
 197                 }
 198         }
 199
 200         netif_carrier_off(ndev);
 201         ntb_transport_link_up(dev->qp);
 202
 203         return 0;
 204
 205 err:
 206         while ((skb = ntb_transport_rx_remove(dev->qp, &len)))
 207                 dev_kfree_skb(skb);
 208         return rc;
 209 }
 210
 211 static int ntb_netdev_close(struct net_device *ndev)
 212 {
 213         struct ntb_netdev *dev = netdev_priv(ndev);
 214         struct sk_buff *skb;
 215         int len;
 216
 217         ntb_transport_link_down(dev->qp);
 218
 219         while ((skb = ntb_transport_rx_remove(dev->qp, &len)))
 220                 dev_kfree_skb(skb);
 221
 222         return 0;
 223 }
 224
 225 static int ntb_netdev_change_mtu(struct net_device *ndev, int new_mtu)
 226 {
 227         struct ntb_netdev *dev = netdev_priv(ndev);
 228         struct sk_buff *skb;
 229         int len, rc;
 230
 231         if (new_mtu > ntb_transport_max_size(dev->qp) - ETH_HLEN)
 232                 return -EINVAL;
 233
 234         if (!netif_running(ndev)) {
 235                 ndev->mtu = new_mtu;
 236                 return 0;
 237         }
 238
 239         /* Bring down the link and dispose of posted rx entries */
 240         ntb_transport_link_down(dev->qp);
 241
 242         if (ndev->mtu < new_mtu) {
 243                 int i;
 244
 245                 for (i = 0; (skb = ntb_transport_rx_remove(dev->qp, &len)); i++)
 246                         dev_kfree_skb(skb);
 247
 248                 for (; i; i--) {
 249                         skb = netdev_alloc_skb(ndev, new_mtu + ETH_HLEN);
 250                         if (!skb) {
 251                                 rc = -ENOMEM;
 252                                 goto err;
 253                         }
 254
 255                         rc = ntb_transport_rx_enqueue(dev->qp, skb, skb->data,
 256                                                       new_mtu + ETH_HLEN);
 257                         if (rc) {
 258                                 dev_kfree_skb(skb);
 259                                 goto err;
 260                         }
 261                 }
 262         }
 263
 264         ndev->mtu = new_mtu;
 265
 266         ntb_transport_link_up(dev->qp);
 267
 268         return 0;
 269
 270 err:
 271         ntb_transport_link_down(dev->qp);
 272
 273         while ((skb = ntb_transport_rx_remove(dev->qp, &len)))
 274                 dev_kfree_skb(skb);
 275
 276         netdev_err(ndev, "Error changing MTU, device inoperable\n");
 277         return rc;
 278 }
 279
 280 static const struct net_device_ops ntb_netdev_ops = {
 281         .ndo_open = ntb_netdev_open,
 282         .ndo_stop = ntb_netdev_close,
 283         .ndo_start_xmit = ntb_netdev_start_xmit,
 284         .ndo_change_mtu = ntb_netdev_change_mtu,
 285         .ndo_set_mac_address = eth_mac_addr,
 286 };
 287
 288 static void ntb_get_drvinfo(struct net_device *ndev,
 289                             struct ethtool_drvinfo *info)
 290 {
 291         struct ntb_netdev *dev = netdev_priv(ndev);
 292
 293         strlcpy(info->driver, KBUILD_MODNAME, sizeof(info->driver));
 294         strlcpy(info->version, NTB_NETDEV_VER, sizeof(info->version));
 295         strlcpy(info->bus_info, pci_name(dev->pdev), sizeof(info->bus_info));
 296 }
 297
 298 static int ntb_get_settings(struct net_device *dev, struct ethtool_cmd *cmd)
 299 {
 300         cmd->supported = SUPPORTED_Backplane;
 301         cmd->advertising = ADVERTISED_Backplane;
 302         ethtool_cmd_speed_set(cmd, SPEED_UNKNOWN);
 303         cmd->duplex = DUPLEX_FULL;
 304         cmd->port = PORT_OTHER;
 305         cmd->phy_address = 0;
 306         cmd->transceiver = XCVR_DUMMY1;
 307         cmd->autoneg = AUTONEG_ENABLE;
 308         cmd->maxtxpkt = 0;
 309         cmd->maxrxpkt = 0;
 310
 311         return 0;
 312 }
 313
 314 static const struct ethtool_ops ntb_ethtool_ops = {
 315         .get_drvinfo = ntb_get_drvinfo,
 316         .get_link = ethtool_op_get_link,
 317         .get_settings = ntb_get_settings,
 318 };
 319
 320 static const struct ntb_queue_handlers ntb_netdev_handlers = {
 321         .tx_handler = ntb_netdev_tx_handler,
 322         .rx_handler = ntb_netdev_rx_handler,
 323         .event_handler = ntb_netdev_event_handler,
 324 };
 325
 326 static int ntb_netdev_probe(struct device *client_dev)
 327 {
 328         struct ntb_dev *ntb;
 329         struct net_device *ndev;
 330         struct pci_dev *pdev;
 331         struct ntb_netdev *dev;
 332         int rc;
 333
 334         ntb = dev_ntb(client_dev->parent);
 335         pdev = ntb->pdev;
 336         if (!pdev)
 337                 return -ENODEV;
 338
 339         ndev = alloc_etherdev(sizeof(*dev));
 340         if (!ndev)
 341                 return -ENOMEM;
 342
 343         dev = netdev_priv(ndev);
 344         dev->ndev = ndev;
 345         dev->pdev = pdev;
 346         ndev->features = NETIF_F_HIGHDMA;
 347
 348         ndev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
 349
 350         ndev->hw_features = ndev->features;
 351         ndev->watchdog_timeo = msecs_to_jiffies(NTB_TX_TIMEOUT_MS);
 352
 353         random_ether_addr(ndev->perm_addr);
 354         memcpy(ndev->dev_addr, ndev->perm_addr, ndev->addr_len);
 355
 356         ndev->netdev_ops = &ntb_netdev_ops;
 357         ndev->ethtool_ops = &ntb_ethtool_ops;
 358
 359         dev->qp = ntb_transport_create_queue(ndev, client_dev,
 360                                              &ntb_netdev_handlers);
 361         if (!dev->qp) {
 362                 rc = -EIO;
 363                 goto err;
 364         }
 365
 366         ndev->mtu = ntb_transport_max_size(dev->qp) - ETH_HLEN;
 367
 368         rc = register_netdev(ndev);
 369         if (rc)
 370                 goto err1;
 371
 372         list_add(&dev->list, &dev_list);
 373         dev_info(&pdev->dev, "%s created\n", ndev->name);
 374         return 0;
 375
 376 err1:
 377         ntb_transport_free_queue(dev->qp);
 378 err:
 379         free_netdev(ndev);
 380         return rc;
 381 }
 382
 383 static void ntb_netdev_remove(struct device *client_dev)
 384 {
 385         struct ntb_dev *ntb;
 386         struct net_device *ndev;
 387         struct pci_dev *pdev;
 388         struct ntb_netdev *dev;
 389         bool found = false;
 390
 391         ntb = dev_ntb(client_dev->parent);
 392         pdev = ntb->pdev;
 393
 394         list_for_each_entry(dev, &dev_list, list) {
 395                 if (dev->pdev == pdev) {
 396                         found = true;
 397                         break;
 398                 }
 399         }
 400         if (!found)
 401                 return;
 402
 403         list_del(&dev->list);
 404
 405         ndev = dev->ndev;
 406
 407         unregister_netdev(ndev);
 408         ntb_transport_free_queue(dev->qp);
 409         free_netdev(ndev);
 410 }
 411
 412 static struct ntb_transport_client ntb_netdev_client = {
 413         .driver.name = KBUILD_MODNAME,
 414         .driver.owner = THIS_MODULE,
 415         .probe = ntb_netdev_probe,
 416         .remove = ntb_netdev_remove,
 417 };
 418
 419 static int __init ntb_netdev_init_module(void)
 420 {
 421         int rc;
 422
 423         rc = ntb_transport_register_client_dev(KBUILD_MODNAME);
 424         if (rc)
 425                 return rc;
 426         return ntb_transport_register_client(&ntb_netdev_client);
 427 }
 428 module_init(ntb_netdev_init_module);
 429
 430 static void __exit ntb_netdev_exit_module(void)
 431 {
 432         ntb_transport_unregister_client(&ntb_netdev_client);
 433         ntb_transport_unregister_client_dev(KBUILD_MODNAME);
 434 }
 435 module_exit(ntb_netdev_exit_module);