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