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         /* Currently, only link status event is supported */
  82         if (status)
  83                 netif_carrier_on(ndev);
  84         else
  85                 netif_carrier_off(ndev);
  86 }
  87
  88 static void ntb_netdev_rx_handler(struct ntb_transport_qp *qp, void *qp_data,
  89                                   void *data, int len)
  90 {
  91         struct net_device *ndev = qp_data;
  92         struct sk_buff *skb;
  93         int rc;
  94
  95         skb = data;
  96         if (!skb)
  97                 return;
  98
  99         netdev_dbg(ndev, "%s: %d byte payload received\n", __func__, len);
 100
 101         skb_put(skb, len);
 102         skb->protocol = eth_type_trans(skb, ndev);
 103         skb->ip_summed = CHECKSUM_NONE;
 104
 105         if (netif_rx(skb) == NET_RX_DROP) {
 106                 ndev->stats.rx_errors++;
 107                 ndev->stats.rx_dropped++;
 108         } else {
 109                 ndev->stats.rx_packets++;
 110                 ndev->stats.rx_bytes += len;
 111         }
 112
 113         skb = netdev_alloc_skb(ndev, ndev->mtu + ETH_HLEN);
 114         if (!skb) {
 115                 ndev->stats.rx_errors++;
 116                 ndev->stats.rx_frame_errors++;
 117                 return;
 118         }
 119
 120         rc = ntb_transport_rx_enqueue(qp, skb, skb->data, ndev->mtu + ETH_HLEN);
 121         if (rc) {
 122                 dev_kfree_skb(skb);
 123                 ndev->stats.rx_errors++;
 124                 ndev->stats.rx_fifo_errors++;
 125         }
 126 }
 127
 128 static void ntb_netdev_tx_handler(struct ntb_transport_qp *qp, void *qp_data,
 129                                   void *data, int len)
 130 {
 131         struct net_device *ndev = qp_data;
 132         struct sk_buff *skb;
 133
 134         skb = data;
 135         if (!skb || !ndev)
 136                 return;
 137
 138         if (len > 0) {
 139                 ndev->stats.tx_packets++;
 140                 ndev->stats.tx_bytes += skb->len;
 141         } else {
 142                 ndev->stats.tx_errors++;
 143                 ndev->stats.tx_aborted_errors++;
 144         }
 145
 146         dev_kfree_skb(skb);
 147 }
 148
 149 static netdev_tx_t ntb_netdev_start_xmit(struct sk_buff *skb,
 150                                          struct net_device *ndev)
 151 {
 152         struct ntb_netdev *dev = netdev_priv(ndev);
 153         int rc;
 154
 155         netdev_dbg(ndev, "%s: skb len %d\n", __func__, skb->len);
 156
 157         rc = ntb_transport_tx_enqueue(dev->qp, skb, skb->data, skb->len);
 158         if (rc)
 159                 goto err;
 160
 161         return NETDEV_TX_OK;
 162
 163 err:
 164         ndev->stats.tx_dropped++;
 165         ndev->stats.tx_errors++;
 166         return NETDEV_TX_BUSY;
 167 }
 168
 169 static int ntb_netdev_open(struct net_device *ndev)
 170 {
 171         struct ntb_netdev *dev = netdev_priv(ndev);
 172         struct sk_buff *skb;
 173         int rc, i, len;
 174
 175         /* Add some empty rx bufs */
 176         for (i = 0; i < NTB_RXQ_SIZE; i++) {
 177                 skb = netdev_alloc_skb(ndev, ndev->mtu + ETH_HLEN);
 178                 if (!skb) {
 179                         rc = -ENOMEM;
 180                         goto err;
 181                 }
 182
 183                 rc = ntb_transport_rx_enqueue(dev->qp, skb, skb->data,
 184                                               ndev->mtu + ETH_HLEN);
 185                 if (rc == -EINVAL)
 186                         goto err;
 187         }
 188
 189         netif_carrier_off(ndev);
 190         ntb_transport_link_up(dev->qp);
 191
 192         return 0;
 193
 194 err:
 195         while ((skb = ntb_transport_rx_remove(dev->qp, &len)))
 196                 dev_kfree_skb(skb);
 197         return rc;
 198 }
 199
 200 static int ntb_netdev_close(struct net_device *ndev)
 201 {
 202         struct ntb_netdev *dev = netdev_priv(ndev);
 203         struct sk_buff *skb;
 204         int len;
 205
 206         ntb_transport_link_down(dev->qp);
 207
 208         while ((skb = ntb_transport_rx_remove(dev->qp, &len)))
 209                 dev_kfree_skb(skb);
 210
 211         return 0;
 212 }
 213
 214 static int ntb_netdev_change_mtu(struct net_device *ndev, int new_mtu)
 215 {
 216         struct ntb_netdev *dev = netdev_priv(ndev);
 217         struct sk_buff *skb;
 218         int len, rc;
 219
 220         if (new_mtu > ntb_transport_max_size(dev->qp) - ETH_HLEN)
 221                 return -EINVAL;
 222
 223         if (!netif_running(ndev)) {
 224                 ndev->mtu = new_mtu;
 225                 return 0;
 226         }
 227
 228         /* Bring down the link and dispose of posted rx entries */
 229         ntb_transport_link_down(dev->qp);
 230
 231         if (ndev->mtu < new_mtu) {
 232                 int i;
 233
 234                 for (i = 0; (skb = ntb_transport_rx_remove(dev->qp, &len)); i++)
 235                         dev_kfree_skb(skb);
 236
 237                 for (; i; i--) {
 238                         skb = netdev_alloc_skb(ndev, new_mtu + ETH_HLEN);
 239                         if (!skb) {
 240                                 rc = -ENOMEM;
 241                                 goto err;
 242                         }
 243
 244                         rc = ntb_transport_rx_enqueue(dev->qp, skb, skb->data,
 245                                                       new_mtu + ETH_HLEN);
 246                         if (rc) {
 247                                 dev_kfree_skb(skb);
 248                                 goto err;
 249                         }
 250                 }
 251         }
 252
 253         ndev->mtu = new_mtu;
 254
 255         ntb_transport_link_up(dev->qp);
 256
 257         return 0;
 258
 259 err:
 260         ntb_transport_link_down(dev->qp);
 261
 262         while ((skb = ntb_transport_rx_remove(dev->qp, &len)))
 263                 dev_kfree_skb(skb);
 264
 265         netdev_err(ndev, "Error changing MTU, device inoperable\n");
 266         return rc;
 267 }
 268
 269 static const struct net_device_ops ntb_netdev_ops = {
 270         .ndo_open = ntb_netdev_open,
 271         .ndo_stop = ntb_netdev_close,
 272         .ndo_start_xmit = ntb_netdev_start_xmit,
 273         .ndo_change_mtu = ntb_netdev_change_mtu,
 274         .ndo_set_mac_address = eth_mac_addr,
 275 };
 276
 277 static void ntb_get_drvinfo(struct net_device *ndev,
 278                             struct ethtool_drvinfo *info)
 279 {
 280         struct ntb_netdev *dev = netdev_priv(ndev);
 281
 282         strlcpy(info->driver, KBUILD_MODNAME, sizeof(info->driver));
 283         strlcpy(info->version, NTB_NETDEV_VER, sizeof(info->version));
 284         strlcpy(info->bus_info, pci_name(dev->pdev), sizeof(info->bus_info));
 285 }
 286
 287 static int ntb_get_settings(struct net_device *dev, struct ethtool_cmd *cmd)
 288 {
 289         cmd->supported = SUPPORTED_Backplane;
 290         cmd->advertising = ADVERTISED_Backplane;
 291         cmd->speed = SPEED_UNKNOWN;
 292         ethtool_cmd_speed_set(cmd, SPEED_UNKNOWN);
 293         cmd->duplex = DUPLEX_FULL;
 294         cmd->port = PORT_OTHER;
 295         cmd->phy_address = 0;
 296         cmd->transceiver = XCVR_DUMMY1;
 297         cmd->autoneg = AUTONEG_ENABLE;
 298         cmd->maxtxpkt = 0;
 299         cmd->maxrxpkt = 0;
 300
 301         return 0;
 302 }
 303
 304 static const struct ethtool_ops ntb_ethtool_ops = {
 305         .get_drvinfo = ntb_get_drvinfo,
 306         .get_link = ethtool_op_get_link,
 307         .get_settings = ntb_get_settings,
 308 };
 309
 310 static const struct ntb_queue_handlers ntb_netdev_handlers = {
 311         .tx_handler = ntb_netdev_tx_handler,
 312         .rx_handler = ntb_netdev_rx_handler,
 313         .event_handler = ntb_netdev_event_handler,
 314 };
 315
 316 static int ntb_netdev_probe(struct pci_dev *pdev)
 317 {
 318         struct net_device *ndev;
 319         struct ntb_netdev *dev;
 320         int rc;
 321
 322         ndev = alloc_etherdev(sizeof(struct ntb_netdev));
 323         if (!ndev)
 324                 return -ENOMEM;
 325
 326         dev = netdev_priv(ndev);
 327         dev->ndev = ndev;
 328         dev->pdev = pdev;
 329         BUG_ON(!dev->pdev);
 330         ndev->features = NETIF_F_HIGHDMA;
 331
 332         ndev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
 333
 334         ndev->hw_features = ndev->features;
 335         ndev->watchdog_timeo = msecs_to_jiffies(NTB_TX_TIMEOUT_MS);
 336
 337         random_ether_addr(ndev->perm_addr);
 338         memcpy(ndev->dev_addr, ndev->perm_addr, ndev->addr_len);
 339
 340         ndev->netdev_ops = &ntb_netdev_ops;
 341         SET_ETHTOOL_OPS(ndev, &ntb_ethtool_ops);
 342
 343         dev->qp = ntb_transport_create_queue(ndev, pdev, &ntb_netdev_handlers);
 344         if (!dev->qp) {
 345                 rc = -EIO;
 346                 goto err;
 347         }
 348
 349         ndev->mtu = ntb_transport_max_size(dev->qp) - ETH_HLEN;
 350
 351         rc = register_netdev(ndev);
 352         if (rc)
 353                 goto err1;
 354
 355         list_add(&dev->list, &dev_list);
 356         dev_info(&pdev->dev, "%s created\n", ndev->name);
 357         return 0;
 358
 359 err1:
 360         ntb_transport_free_queue(dev->qp);
 361 err:
 362         free_netdev(ndev);
 363         return rc;
 364 }
 365
 366 static void ntb_netdev_remove(struct pci_dev *pdev)
 367 {
 368         struct net_device *ndev;
 369         struct ntb_netdev *dev;
 370
 371         list_for_each_entry(dev, &dev_list, list) {
 372                 if (dev->pdev == pdev)
 373                         break;
 374         }
 375         if (dev == NULL)
 376                 return;
 377
 378         ndev = dev->ndev;
 379
 380         unregister_netdev(ndev);
 381         ntb_transport_free_queue(dev->qp);
 382         free_netdev(ndev);
 383 }
 384
 385 static struct ntb_client ntb_netdev_client = {
 386         .driver.name = KBUILD_MODNAME,
 387         .driver.owner = THIS_MODULE,
 388         .probe = ntb_netdev_probe,
 389         .remove = ntb_netdev_remove,
 390 };
 391
 392 static int __init ntb_netdev_init_module(void)
 393 {
 394         int rc;
 395
 396         rc = ntb_register_client_dev(KBUILD_MODNAME);
 397         if (rc)
 398                 return rc;
 399         return ntb_register_client(&ntb_netdev_client);
 400 }
 401 module_init(ntb_netdev_init_module);
 402
 403 static void __exit ntb_netdev_exit_module(void)
 404 {
 405         ntb_unregister_client(&ntb_netdev_client);
 406         ntb_unregister_client_dev(KBUILD_MODNAME);
 407 }
 408 module_exit(ntb_netdev_exit_module);