drivers/staging/hv/netvsc_drv.c

   1 /*
   2  * Copyright (c) 2009, Microsoft Corporation.
   3  *
   4  * This program is free software; you can redistribute it and/or modify it
   5  * under the terms and conditions of the GNU General Public License,
   6  * version 2, as published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope it will be useful, but WITHOUT
   9  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  10  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  11  * more details.
  12  *
  13  * You should have received a copy of the GNU General Public License along with
  14  * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
  15  * Place - Suite 330, Boston, MA 02111-1307 USA.
  16  *
  17  * Authors:
  18  *   Haiyang Zhang <haiyangz@microsoft.com>
  19  *   Hank Janssen  <hjanssen@microsoft.com>
  20  */
  21 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  22
  23 #include <linux/init.h>
  24 #include <linux/module.h>
  25 #include <linux/highmem.h>
  26 #include <linux/device.h>
  27 #include <linux/io.h>
  28 #include <linux/delay.h>
  29 #include <linux/netdevice.h>
  30 #include <linux/inetdevice.h>
  31 #include <linux/etherdevice.h>
  32 #include <linux/skbuff.h>
  33 #include <linux/in.h>
  34 #include <linux/slab.h>
  35 #include <linux/dmi.h>
  36 #include <linux/pci.h>
  37 #include <net/arp.h>
  38 #include <net/route.h>
  39 #include <net/sock.h>
  40 #include <net/pkt_sched.h>
  41
  42 #include "hyperv.h"
  43 #include "hyperv_net.h"
  44
  45 struct net_device_context {
  46         /* point back to our device context */
  47         struct hv_device *device_ctx;
  48         unsigned long avail;
  49         struct work_struct work;
  50 };
  51
  52
  53 #define PACKET_PAGES_LOWATER  8
  54 /* Need this many pages to handle worst case fragmented packet */
  55 #define PACKET_PAGES_HIWATER  (MAX_SKB_FRAGS + 2)
  56
  57 static int ring_size = 128;
  58 module_param(ring_size, int, S_IRUGO);
  59 MODULE_PARM_DESC(ring_size, "Ring buffer size (# of pages)");
  60
  61 /* no-op so the netdev core doesn't return -EINVAL when modifying the the
  62  * multicast address list in SIOCADDMULTI. hv is setup to get all multicast
  63  * when it calls RndisFilterOnOpen() */
  64 static void netvsc_set_multicast_list(struct net_device *net)
  65 {
  66 }
  67
  68 static int netvsc_open(struct net_device *net)
  69 {
  70         struct net_device_context *net_device_ctx = netdev_priv(net);
  71         struct hv_device *device_obj = net_device_ctx->device_ctx;
  72         int ret = 0;
  73
  74         if (netif_carrier_ok(net)) {
  75                 /* Open up the device */
  76                 ret = rndis_filter_open(device_obj);
  77                 if (ret != 0) {
  78                         netdev_err(net, "unable to open device (ret %d).\n",
  79                                    ret);
  80                         return ret;
  81                 }
  82
  83                 netif_start_queue(net);
  84         } else {
  85                 netdev_err(net, "unable to open device...link is down.\n");
  86         }
  87
  88         return ret;
  89 }
  90
  91 static int netvsc_close(struct net_device *net)
  92 {
  93         struct net_device_context *net_device_ctx = netdev_priv(net);
  94         struct hv_device *device_obj = net_device_ctx->device_ctx;
  95         int ret;
  96
  97         netif_stop_queue(net);
  98
  99         ret = rndis_filter_close(device_obj);
 100         if (ret != 0)
 101                 netdev_err(net, "unable to close device (ret %d).\n", ret);
 102
 103         return ret;
 104 }
 105
 106 static void netvsc_xmit_completion(void *context)
 107 {
 108         struct hv_netvsc_packet *packet = (struct hv_netvsc_packet *)context;
 109         struct sk_buff *skb = (struct sk_buff *)
 110                 (unsigned long)packet->completion.send.send_completion_tid;
 111
 112         kfree(packet);
 113
 114         if (skb) {
 115                 struct net_device *net = skb->dev;
 116                 struct net_device_context *net_device_ctx = netdev_priv(net);
 117                 unsigned int num_pages = skb_shinfo(skb)->nr_frags + 2;
 118
 119                 dev_kfree_skb_any(skb);
 120
 121                 net_device_ctx->avail += num_pages;
 122                 if (net_device_ctx->avail >= PACKET_PAGES_HIWATER)
 123                         netif_wake_queue(net);
 124         }
 125 }
 126
 127 static int netvsc_start_xmit(struct sk_buff *skb, struct net_device *net)
 128 {
 129         struct net_device_context *net_device_ctx = netdev_priv(net);
 130         struct netvsc_driver *net_drv_obj =
 131                 drv_to_netvscdrv(net_device_ctx->device_ctx->device.driver);
 132         struct hv_netvsc_packet *packet;
 133         int ret;
 134         unsigned int i, num_pages;
 135
 136         /* Add 1 for skb->data and additional one for RNDIS */
 137         num_pages = skb_shinfo(skb)->nr_frags + 1 + 1;
 138         if (num_pages > net_device_ctx->avail)
 139                 return NETDEV_TX_BUSY;
 140
 141         /* Allocate a netvsc packet based on # of frags. */
 142         packet = kzalloc(sizeof(struct hv_netvsc_packet) +
 143                          (num_pages * sizeof(struct hv_page_buffer)) +
 144                          net_drv_obj->req_ext_size, GFP_ATOMIC);
 145         if (!packet) {
 146                 /* out of memory, silently drop packet */
 147                 netdev_err(net, "unable to allocate hv_netvsc_packet\n");
 148
 149                 dev_kfree_skb(skb);
 150                 net->stats.tx_dropped++;
 151                 return NETDEV_TX_OK;
 152         }
 153
 154         packet->extension = (void *)(unsigned long)packet +
 155                                 sizeof(struct hv_netvsc_packet) +
 156                                     (num_pages * sizeof(struct hv_page_buffer));
 157
 158         /* Setup the rndis header */
 159         packet->page_buf_cnt = num_pages;
 160
 161         /* TODO: Flush all write buffers/ memory fence ??? */
 162         /* wmb(); */
 163
 164         /* Initialize it from the skb */
 165         packet->total_data_buflen       = skb->len;
 166
 167         /* Start filling in the page buffers starting after RNDIS buffer. */
 168         packet->page_buf[1].pfn = virt_to_phys(skb->data) >> PAGE_SHIFT;
 169         packet->page_buf[1].offset
 170                 = (unsigned long)skb->data & (PAGE_SIZE - 1);
 171         packet->page_buf[1].len = skb_headlen(skb);
 172
 173         /* Additional fragments are after SKB data */
 174         for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
 175                 skb_frag_t *f = &skb_shinfo(skb)->frags[i];
 176
 177                 packet->page_buf[i+2].pfn = page_to_pfn(f->page);
 178                 packet->page_buf[i+2].offset = f->page_offset;
 179                 packet->page_buf[i+2].len = f->size;
 180         }
 181
 182         /* Set the completion routine */
 183         packet->completion.send.send_completion = netvsc_xmit_completion;
 184         packet->completion.send.send_completion_ctx = packet;
 185         packet->completion.send.send_completion_tid = (unsigned long)skb;
 186
 187         ret = net_drv_obj->send(net_device_ctx->device_ctx,
 188                                   packet);
 189         if (ret == 0) {
 190                 net->stats.tx_bytes += skb->len;
 191                 net->stats.tx_packets++;
 192
 193                 net_device_ctx->avail -= num_pages;
 194                 if (net_device_ctx->avail < PACKET_PAGES_LOWATER)
 195                         netif_stop_queue(net);
 196         } else {
 197                 /* we are shutting down or bus overloaded, just drop packet */
 198                 net->stats.tx_dropped++;
 199                 netvsc_xmit_completion(packet);
 200         }
 201
 202         return NETDEV_TX_OK;
 203 }
 204
 205 /*
 206  * netvsc_linkstatus_callback - Link up/down notification
 207  */
 208 void netvsc_linkstatus_callback(struct hv_device *device_obj,
 209                                        unsigned int status)
 210 {
 211         struct net_device *net = dev_get_drvdata(&device_obj->device);
 212         struct net_device_context *ndev_ctx;
 213
 214         if (!net) {
 215                 netdev_err(net, "got link status but net device "
 216                                 "not initialized yet\n");
 217                 return;
 218         }
 219
 220         if (status == 1) {
 221                 netif_carrier_on(net);
 222                 netif_wake_queue(net);
 223                 netif_notify_peers(net);
 224                 ndev_ctx = netdev_priv(net);
 225                 schedule_work(&ndev_ctx->work);
 226         } else {
 227                 netif_carrier_off(net);
 228                 netif_stop_queue(net);
 229         }
 230 }
 231
 232 /*
 233  * netvsc_recv_callback -  Callback when we receive a packet from the
 234  * "wire" on the specified device.
 235  */
 236 static int netvsc_recv_callback(struct hv_device *device_obj,
 237                                 struct hv_netvsc_packet *packet)
 238 {
 239         struct net_device *net = dev_get_drvdata(&device_obj->device);
 240         struct sk_buff *skb;
 241         void *data;
 242         int i;
 243         unsigned long flags;
 244
 245         if (!net) {
 246                 netdev_err(net, "got receive callback but net device"
 247                         " not initialized yet\n");
 248                 return 0;
 249         }
 250
 251         /* Allocate a skb - TODO direct I/O to pages? */
 252         skb = netdev_alloc_skb_ip_align(net, packet->total_data_buflen);
 253         if (unlikely(!skb)) {
 254                 ++net->stats.rx_dropped;
 255                 return 0;
 256         }
 257
 258         /* for kmap_atomic */
 259         local_irq_save(flags);
 260
 261         /*
 262          * Copy to skb. This copy is needed here since the memory pointed by
 263          * hv_netvsc_packet cannot be deallocated
 264          */
 265         for (i = 0; i < packet->page_buf_cnt; i++) {
 266                 data = kmap_atomic(pfn_to_page(packet->page_buf[i].pfn),
 267                                                KM_IRQ1);
 268                 data = (void *)(unsigned long)data +
 269                                 packet->page_buf[i].offset;
 270
 271                 memcpy(skb_put(skb, packet->page_buf[i].len), data,
 272                        packet->page_buf[i].len);
 273
 274                 kunmap_atomic((void *)((unsigned long)data -
 275                                        packet->page_buf[i].offset), KM_IRQ1);
 276         }
 277
 278         local_irq_restore(flags);
 279
 280         skb->protocol = eth_type_trans(skb, net);
 281         skb->ip_summed = CHECKSUM_NONE;
 282
 283         net->stats.rx_packets++;
 284         net->stats.rx_bytes += skb->len;
 285
 286         /*
 287          * Pass the skb back up. Network stack will deallocate the skb when it
 288          * is done.
 289          * TODO - use NAPI?
 290          */
 291         netif_rx(skb);
 292
 293         return 0;
 294 }
 295
 296 static void netvsc_get_drvinfo(struct net_device *net,
 297                                struct ethtool_drvinfo *info)
 298 {
 299         strcpy(info->driver, "hv_netvsc");
 300         strcpy(info->version, HV_DRV_VERSION);
 301         strcpy(info->fw_version, "N/A");
 302 }
 303
 304 static const struct ethtool_ops ethtool_ops = {
 305         .get_drvinfo    = netvsc_get_drvinfo,
 306         .get_link       = ethtool_op_get_link,
 307 };
 308
 309 static const struct net_device_ops device_ops = {
 310         .ndo_open =                     netvsc_open,
 311         .ndo_stop =                     netvsc_close,
 312         .ndo_start_xmit =               netvsc_start_xmit,
 313         .ndo_set_multicast_list =       netvsc_set_multicast_list,
 314         .ndo_change_mtu =               eth_change_mtu,
 315         .ndo_validate_addr =            eth_validate_addr,
 316         .ndo_set_mac_address =          eth_mac_addr,
 317 };
 318
 319 /*
 320  * Send GARP packet to network peers after migrations.
 321  * After Quick Migration, the network is not immediately operational in the
 322  * current context when receiving RNDIS_STATUS_MEDIA_CONNECT event. So, add
 323  * another netif_notify_peers() into a scheduled work, otherwise GARP packet
 324  * will not be sent after quick migration, and cause network disconnection.
 325  */
 326 static void netvsc_send_garp(struct work_struct *w)
 327 {
 328         struct net_device_context *ndev_ctx;
 329         struct net_device *net;
 330
 331         msleep(20);
 332         ndev_ctx = container_of(w, struct net_device_context, work);
 333         net = dev_get_drvdata(&ndev_ctx->device_ctx->device);
 334         netif_notify_peers(net);
 335 }
 336
 337
 338 static int netvsc_probe(struct hv_device *dev)
 339 {
 340         struct net_device *net = NULL;
 341         struct net_device_context *net_device_ctx;
 342         struct netvsc_device_info device_info;
 343         int ret;
 344
 345         net = alloc_etherdev(sizeof(struct net_device_context));
 346         if (!net)
 347                 return -1;
 348
 349         /* Set initial state */
 350         netif_carrier_off(net);
 351
 352         net_device_ctx = netdev_priv(net);
 353         net_device_ctx->device_ctx = dev;
 354         net_device_ctx->avail = ring_size;
 355         dev_set_drvdata(&dev->device, net);
 356         INIT_WORK(&net_device_ctx->work, netvsc_send_garp);
 357
 358         /* Notify the netvsc driver of the new device */
 359         ret = rndis_filte_device_add(dev, &device_info);
 360         if (ret != 0) {
 361                 free_netdev(net);
 362                 dev_set_drvdata(&dev->device, NULL);
 363
 364                 netdev_err(net, "unable to add netvsc device (ret %d)\n", ret);
 365                 return ret;
 366         }
 367
 368         /*
 369          * If carrier is still off ie we did not get a link status callback,
 370          * update it if necessary
 371          */
 372         /*
 373          * FIXME: We should use a atomic or test/set instead to avoid getting
 374          * out of sync with the device's link status
 375          */
 376         if (!netif_carrier_ok(net))
 377                 if (!device_info.link_state)
 378                         netif_carrier_on(net);
 379
 380         memcpy(net->dev_addr, device_info.mac_adr, ETH_ALEN);
 381
 382         net->netdev_ops = &device_ops;
 383
 384         /* TODO: Add GSO and Checksum offload */
 385         net->hw_features = NETIF_F_SG;
 386         net->features = NETIF_F_SG;
 387
 388         SET_ETHTOOL_OPS(net, &ethtool_ops);
 389         SET_NETDEV_DEV(net, &dev->device);
 390
 391         ret = register_netdev(net);
 392         if (ret != 0) {
 393                 /* Remove the device and release the resource */
 394                 rndis_filter_device_remove(dev);
 395                 free_netdev(net);
 396         }
 397
 398         return ret;
 399 }
 400
 401 static int netvsc_remove(struct hv_device *dev)
 402 {
 403         struct net_device *net = dev_get_drvdata(&dev->device);
 404         int ret;
 405
 406         if (net == NULL) {
 407                 dev_err(&dev->device, "No net device to remove\n");
 408                 return 0;
 409         }
 410
 411         /* Stop outbound asap */
 412         netif_stop_queue(net);
 413         /* netif_carrier_off(net); */
 414
 415         unregister_netdev(net);
 416
 417         /*
 418          * Call to the vsc driver to let it know that the device is being
 419          * removed
 420          */
 421         ret = rndis_filter_device_remove(dev);
 422         if (ret != 0) {
 423                 /* TODO: */
 424                 netdev_err(net, "unable to remove vsc device (ret %d)\n", ret);
 425         }
 426
 427         free_netdev(net);
 428         return ret;
 429 }
 430
 431 /* The one and only one */
 432 static struct  netvsc_driver netvsc_drv = {
 433         .base.probe = netvsc_probe,
 434         .base.remove = netvsc_remove,
 435 };
 436
 437 static void netvsc_drv_exit(void)
 438 {
 439         vmbus_child_driver_unregister(&netvsc_drv.base.driver);
 440 }
 441
 442 static int netvsc_drv_init(int (*drv_init)(struct hv_driver *drv))
 443 {
 444         struct netvsc_driver *net_drv_obj = &netvsc_drv;
 445         struct hv_driver *drv = &netvsc_drv.base;
 446         int ret;
 447
 448         net_drv_obj->ring_buf_size = ring_size * PAGE_SIZE;
 449         net_drv_obj->recv_cb = netvsc_recv_callback;
 450         net_drv_obj->link_status_change = netvsc_linkstatus_callback;
 451
 452         /* Callback to client driver to complete the initialization */
 453         drv_init(&net_drv_obj->base);
 454
 455         drv->driver.name = net_drv_obj->base.name;
 456
 457         /* The driver belongs to vmbus */
 458         ret = vmbus_child_driver_register(&drv->driver);
 459
 460         return ret;
 461 }
 462
 463 static const struct dmi_system_id __initconst
 464 hv_netvsc_dmi_table[] __maybe_unused  = {
 465         {
 466                 .ident = "Hyper-V",
 467                 .matches = {
 468                         DMI_MATCH(DMI_SYS_VENDOR, "Microsoft Corporation"),
 469                         DMI_MATCH(DMI_PRODUCT_NAME, "Virtual Machine"),
 470                         DMI_MATCH(DMI_BOARD_NAME, "Virtual Machine"),
 471                 },
 472         },
 473         { },
 474 };
 475 MODULE_DEVICE_TABLE(dmi, hv_netvsc_dmi_table);
 476
 477 static int __init netvsc_init(void)
 478 {
 479         pr_info("initializing....");
 480
 481         if (!dmi_check_system(hv_netvsc_dmi_table))
 482                 return -ENODEV;
 483
 484         return netvsc_drv_init(netvsc_initialize);
 485 }
 486
 487 static void __exit netvsc_exit(void)
 488 {
 489         netvsc_drv_exit();
 490 }
 491
 492 static const struct pci_device_id __initconst
 493 hv_netvsc_pci_table[] __maybe_unused = {
 494         { PCI_DEVICE(0x1414, 0x5353) }, /* VGA compatible controller */
 495         { 0 }
 496 };
 497 MODULE_DEVICE_TABLE(pci, hv_netvsc_pci_table);
 498
 499 MODULE_LICENSE("GPL");
 500 MODULE_VERSION(HV_DRV_VERSION);
 501 MODULE_DESCRIPTION("Microsoft Hyper-V network driver");
 502
 503 module_init(netvsc_init);
 504 module_exit(netvsc_exit);