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 #include <linux/init.h>
  22 #include <linux/module.h>
  23 #include <linux/highmem.h>
  24 #include <linux/device.h>
  25 #include <linux/io.h>
  26 #include <linux/delay.h>
  27 #include <linux/netdevice.h>
  28 #include <linux/inetdevice.h>
  29 #include <linux/etherdevice.h>
  30 #include <linux/skbuff.h>
  31 #include <linux/in.h>
  32 #include <linux/slab.h>
  33 #include <linux/dmi.h>
  34 #include <linux/pci.h>
  35 #include <net/arp.h>
  36 #include <net/route.h>
  37 #include <net/sock.h>
  38 #include <net/pkt_sched.h>
  39 #include "osd.h"
  40 #include "logging.h"
  41 #include "version_info.h"
  42 #include "vmbus.h"
  43 #include "netvsc_api.h"
  44
  45 struct net_device_context {
  46         /* point back to our device context */
  47         struct vm_device *device_ctx;
  48         unsigned long avail;
  49 };
  50
  51 struct netvsc_driver_context {
  52         /* !! These must be the first 2 fields !! */
  53         /* Which is a bug FIXME! */
  54         struct driver_context drv_ctx;
  55         struct netvsc_driver drv_obj;
  56 };
  57
  58 #define PACKET_PAGES_LOWATER  8
  59 /* Need this many pages to handle worst case fragmented packet */
  60 #define PACKET_PAGES_HIWATER  (MAX_SKB_FRAGS + 2)
  61
  62 static int ring_size = 128;
  63 module_param(ring_size, int, S_IRUGO);
  64 MODULE_PARM_DESC(ring_size, "Ring buffer size (# of pages)");
  65
  66 /* The one and only one */
  67 static struct netvsc_driver_context g_netvsc_drv;
  68
  69 /* no-op so the netdev core doesn't return -EINVAL when modifying the the
  70  * multicast address list in SIOCADDMULTI. hv is setup to get all multicast
  71  * when it calls RndisFilterOnOpen() */
  72 static void netvsc_set_multicast_list(struct net_device *net)
  73 {
  74 }
  75
  76 static int netvsc_open(struct net_device *net)
  77 {
  78         struct net_device_context *net_device_ctx = netdev_priv(net);
  79         struct hv_device *device_obj = &net_device_ctx->device_ctx->device_obj;
  80         int ret = 0;
  81
  82         if (netif_carrier_ok(net)) {
  83                 /* Open up the device */
  84                 ret = rndis_filter_open(device_obj);
  85                 if (ret != 0) {
  86                         DPRINT_ERR(NETVSC_DRV,
  87                                    "unable to open device (ret %d).", ret);
  88                         return ret;
  89                 }
  90
  91                 netif_start_queue(net);
  92         } else {
  93                 DPRINT_ERR(NETVSC_DRV, "unable to open device...link is down.");
  94         }
  95
  96         return ret;
  97 }
  98
  99 static int netvsc_close(struct net_device *net)
 100 {
 101         struct net_device_context *net_device_ctx = netdev_priv(net);
 102         struct hv_device *device_obj = &net_device_ctx->device_ctx->device_obj;
 103         int ret;
 104
 105         netif_stop_queue(net);
 106
 107         ret = rndis_filter_close(device_obj);
 108         if (ret != 0)
 109                 DPRINT_ERR(NETVSC_DRV, "unable to close device (ret %d).", ret);
 110
 111         return ret;
 112 }
 113
 114 static void netvsc_xmit_completion(void *context)
 115 {
 116         struct hv_netvsc_packet *packet = (struct hv_netvsc_packet *)context;
 117         struct sk_buff *skb = (struct sk_buff *)
 118                 (unsigned long)packet->completion.send.send_completion_tid;
 119
 120         kfree(packet);
 121
 122         if (skb) {
 123                 struct net_device *net = skb->dev;
 124                 struct net_device_context *net_device_ctx = netdev_priv(net);
 125                 unsigned int num_pages = skb_shinfo(skb)->nr_frags + 2;
 126
 127                 dev_kfree_skb_any(skb);
 128
 129                 if ((net_device_ctx->avail += num_pages) >= PACKET_PAGES_HIWATER)
 130                         netif_wake_queue(net);
 131         }
 132 }
 133
 134 static int netvsc_start_xmit(struct sk_buff *skb, struct net_device *net)
 135 {
 136         struct net_device_context *net_device_ctx = netdev_priv(net);
 137         struct driver_context *driver_ctx =
 138             driver_to_driver_context(net_device_ctx->device_ctx->device.driver);
 139         struct netvsc_driver_context *net_drv_ctx =
 140                 (struct netvsc_driver_context *)driver_ctx;
 141         struct netvsc_driver *net_drv_obj = &net_drv_ctx->drv_obj;
 142         struct hv_netvsc_packet *packet;
 143         int ret;
 144         unsigned int i, num_pages;
 145
 146         DPRINT_DBG(NETVSC_DRV, "xmit packet - len %d data_len %d",
 147                    skb->len, skb->data_len);
 148
 149         /* Add 1 for skb->data and additional one for RNDIS */
 150         num_pages = skb_shinfo(skb)->nr_frags + 1 + 1;
 151         if (num_pages > net_device_ctx->avail)
 152                 return NETDEV_TX_BUSY;
 153
 154         /* Allocate a netvsc packet based on # of frags. */
 155         packet = kzalloc(sizeof(struct hv_netvsc_packet) +
 156                          (num_pages * sizeof(struct hv_page_buffer)) +
 157                          net_drv_obj->req_ext_size, GFP_ATOMIC);
 158         if (!packet) {
 159                 /* out of memory, silently drop packet */
 160                 DPRINT_ERR(NETVSC_DRV, "unable to allocate hv_netvsc_packet");
 161
 162                 dev_kfree_skb(skb);
 163                 net->stats.tx_dropped++;
 164                 return NETDEV_TX_OK;
 165         }
 166
 167         packet->extension = (void *)(unsigned long)packet +
 168                                 sizeof(struct hv_netvsc_packet) +
 169                                     (num_pages * sizeof(struct hv_page_buffer));
 170
 171         /* Setup the rndis header */
 172         packet->page_buf_cnt = num_pages;
 173
 174         /* TODO: Flush all write buffers/ memory fence ??? */
 175         /* wmb(); */
 176
 177         /* Initialize it from the skb */
 178         packet->total_data_buflen       = skb->len;
 179
 180         /* Start filling in the page buffers starting after RNDIS buffer. */
 181         packet->page_buf[1].Pfn = virt_to_phys(skb->data) >> PAGE_SHIFT;
 182         packet->page_buf[1].Offset
 183                 = (unsigned long)skb->data & (PAGE_SIZE - 1);
 184         packet->page_buf[1].Length = skb_headlen(skb);
 185
 186         /* Additional fragments are after SKB data */
 187         for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
 188                 skb_frag_t *f = &skb_shinfo(skb)->frags[i];
 189
 190                 packet->page_buf[i+2].Pfn = page_to_pfn(f->page);
 191                 packet->page_buf[i+2].Offset = f->page_offset;
 192                 packet->page_buf[i+2].Length = f->size;
 193         }
 194
 195         /* Set the completion routine */
 196         packet->completion.send.send_completion = netvsc_xmit_completion;
 197         packet->completion.send.send_completion_ctx = packet;
 198         packet->completion.send.send_completion_tid = (unsigned long)skb;
 199
 200         ret = net_drv_obj->send(&net_device_ctx->device_ctx->device_obj,
 201                                   packet);
 202         if (ret == 0) {
 203                 net->stats.tx_bytes += skb->len;
 204                 net->stats.tx_packets++;
 205
 206                 DPRINT_DBG(NETVSC_DRV, "# of xmits %lu total size %lu",
 207                            net->stats.tx_packets,
 208                            net->stats.tx_bytes);
 209
 210                 if ((net_device_ctx->avail -= num_pages) < PACKET_PAGES_LOWATER)
 211                         netif_stop_queue(net);
 212         } else {
 213                 /* we are shutting down or bus overloaded, just drop packet */
 214                 net->stats.tx_dropped++;
 215                 netvsc_xmit_completion(packet);
 216         }
 217
 218         return NETDEV_TX_OK;
 219 }
 220
 221 /*
 222  * netvsc_linkstatus_callback - Link up/down notification
 223  */
 224 static void netvsc_linkstatus_callback(struct hv_device *device_obj,
 225                                        unsigned int status)
 226 {
 227         struct vm_device *device_ctx = to_vm_device(device_obj);
 228         struct net_device *net = dev_get_drvdata(&device_ctx->device);
 229
 230         if (!net) {
 231                 DPRINT_ERR(NETVSC_DRV, "got link status but net device "
 232                                 "not initialized yet");
 233                 return;
 234         }
 235
 236         if (status == 1) {
 237                 netif_carrier_on(net);
 238                 netif_wake_queue(net);
 239                 netif_notify_peers(net);
 240         } else {
 241                 netif_carrier_off(net);
 242                 netif_stop_queue(net);
 243         }
 244 }
 245
 246 /*
 247  * netvsc_recv_callback -  Callback when we receive a packet from the
 248  * "wire" on the specified device.
 249  */
 250 static int netvsc_recv_callback(struct hv_device *device_obj,
 251                                 struct hv_netvsc_packet *packet)
 252 {
 253         struct vm_device *device_ctx = to_vm_device(device_obj);
 254         struct net_device *net = dev_get_drvdata(&device_ctx->device);
 255         struct sk_buff *skb;
 256         void *data;
 257         int i;
 258         unsigned long flags;
 259
 260         if (!net) {
 261                 DPRINT_ERR(NETVSC_DRV, "got receive callback but net device "
 262                                 "not initialized yet");
 263                 return 0;
 264         }
 265
 266         /* Allocate a skb - TODO direct I/O to pages? */
 267         skb = netdev_alloc_skb_ip_align(net, packet->total_data_buflen);
 268         if (unlikely(!skb)) {
 269                 ++net->stats.rx_dropped;
 270                 return 0;
 271         }
 272
 273         /* for kmap_atomic */
 274         local_irq_save(flags);
 275
 276         /*
 277          * Copy to skb. This copy is needed here since the memory pointed by
 278          * hv_netvsc_packet cannot be deallocated
 279          */
 280         for (i = 0; i < packet->page_buf_cnt; i++) {
 281                 data = kmap_atomic(pfn_to_page(packet->page_buf[i].Pfn),
 282                                                KM_IRQ1);
 283                 data = (void *)(unsigned long)data +
 284                                 packet->page_buf[i].Offset;
 285
 286                 memcpy(skb_put(skb, packet->page_buf[i].Length), data,
 287                        packet->page_buf[i].Length);
 288
 289                 kunmap_atomic((void *)((unsigned long)data -
 290                                        packet->page_buf[i].Offset), KM_IRQ1);
 291         }
 292
 293         local_irq_restore(flags);
 294
 295         skb->protocol = eth_type_trans(skb, net);
 296         skb->ip_summed = CHECKSUM_NONE;
 297
 298         net->stats.rx_packets++;
 299         net->stats.rx_bytes += skb->len;
 300
 301         /*
 302          * Pass the skb back up. Network stack will deallocate the skb when it
 303          * is done.
 304          * TODO - use NAPI?
 305          */
 306         netif_rx(skb);
 307
 308         DPRINT_DBG(NETVSC_DRV, "# of recvs %lu total size %lu",
 309                    net->stats.rx_packets, net->stats.rx_bytes);
 310
 311         return 0;
 312 }
 313
 314 static void netvsc_get_drvinfo(struct net_device *net,
 315                                struct ethtool_drvinfo *info)
 316 {
 317         strcpy(info->driver, "hv_netvsc");
 318         strcpy(info->version, HV_DRV_VERSION);
 319         strcpy(info->fw_version, "N/A");
 320 }
 321
 322 static const struct ethtool_ops ethtool_ops = {
 323         .get_drvinfo    = netvsc_get_drvinfo,
 324         .get_sg         = ethtool_op_get_sg,
 325         .set_sg         = ethtool_op_set_sg,
 326         .get_link       = ethtool_op_get_link,
 327 };
 328
 329 static const struct net_device_ops device_ops = {
 330         .ndo_open =                     netvsc_open,
 331         .ndo_stop =                     netvsc_close,
 332         .ndo_start_xmit =               netvsc_start_xmit,
 333         .ndo_set_multicast_list =       netvsc_set_multicast_list,
 334         .ndo_change_mtu =               eth_change_mtu,
 335         .ndo_validate_addr =            eth_validate_addr,
 336         .ndo_set_mac_address =          eth_mac_addr,
 337 };
 338
 339 static int netvsc_probe(struct device *device)
 340 {
 341         struct driver_context *driver_ctx =
 342                 driver_to_driver_context(device->driver);
 343         struct netvsc_driver_context *net_drv_ctx =
 344                 (struct netvsc_driver_context *)driver_ctx;
 345         struct netvsc_driver *net_drv_obj = &net_drv_ctx->drv_obj;
 346         struct vm_device *device_ctx = device_to_vm_device(device);
 347         struct hv_device *device_obj = &device_ctx->device_obj;
 348         struct net_device *net = NULL;
 349         struct net_device_context *net_device_ctx;
 350         struct netvsc_device_info device_info;
 351         int ret;
 352
 353         if (!net_drv_obj->base.OnDeviceAdd)
 354                 return -1;
 355
 356         net = alloc_etherdev(sizeof(struct net_device_context));
 357         if (!net)
 358                 return -1;
 359
 360         /* Set initial state */
 361         netif_carrier_off(net);
 362
 363         net_device_ctx = netdev_priv(net);
 364         net_device_ctx->device_ctx = device_ctx;
 365         net_device_ctx->avail = ring_size;
 366         dev_set_drvdata(device, net);
 367
 368         /* Notify the netvsc driver of the new device */
 369         ret = net_drv_obj->base.OnDeviceAdd(device_obj, &device_info);
 370         if (ret != 0) {
 371                 free_netdev(net);
 372                 dev_set_drvdata(device, NULL);
 373
 374                 DPRINT_ERR(NETVSC_DRV, "unable to add netvsc device (ret %d)",
 375                            ret);
 376                 return ret;
 377         }
 378
 379         /*
 380          * If carrier is still off ie we did not get a link status callback,
 381          * update it if necessary
 382          */
 383         /*
 384          * FIXME: We should use a atomic or test/set instead to avoid getting
 385          * out of sync with the device's link status
 386          */
 387         if (!netif_carrier_ok(net))
 388                 if (!device_info.link_state)
 389                         netif_carrier_on(net);
 390
 391         memcpy(net->dev_addr, device_info.mac_adr, ETH_ALEN);
 392
 393         net->netdev_ops = &device_ops;
 394
 395         /* TODO: Add GSO and Checksum offload */
 396         net->features = NETIF_F_SG;
 397
 398         SET_ETHTOOL_OPS(net, &ethtool_ops);
 399         SET_NETDEV_DEV(net, device);
 400
 401         ret = register_netdev(net);
 402         if (ret != 0) {
 403                 /* Remove the device and release the resource */
 404                 net_drv_obj->base.OnDeviceRemove(device_obj);
 405                 free_netdev(net);
 406         }
 407
 408         return ret;
 409 }
 410
 411 static int netvsc_remove(struct device *device)
 412 {
 413         struct driver_context *driver_ctx =
 414                 driver_to_driver_context(device->driver);
 415         struct netvsc_driver_context *net_drv_ctx =
 416                 (struct netvsc_driver_context *)driver_ctx;
 417         struct netvsc_driver *net_drv_obj = &net_drv_ctx->drv_obj;
 418         struct vm_device *device_ctx = device_to_vm_device(device);
 419         struct net_device *net = dev_get_drvdata(&device_ctx->device);
 420         struct hv_device *device_obj = &device_ctx->device_obj;
 421         int ret;
 422
 423         if (net == NULL) {
 424                 DPRINT_INFO(NETVSC, "no net device to remove");
 425                 return 0;
 426         }
 427
 428         if (!net_drv_obj->base.OnDeviceRemove)
 429                 return -1;
 430
 431         /* Stop outbound asap */
 432         netif_stop_queue(net);
 433         /* netif_carrier_off(net); */
 434
 435         unregister_netdev(net);
 436
 437         /*
 438          * Call to the vsc driver to let it know that the device is being
 439          * removed
 440          */
 441         ret = net_drv_obj->base.OnDeviceRemove(device_obj);
 442         if (ret != 0) {
 443                 /* TODO: */
 444                 DPRINT_ERR(NETVSC, "unable to remove vsc device (ret %d)", ret);
 445         }
 446
 447         free_netdev(net);
 448         return ret;
 449 }
 450
 451 static int netvsc_drv_exit_cb(struct device *dev, void *data)
 452 {
 453         struct device **curr = (struct device **)data;
 454
 455         *curr = dev;
 456         /* stop iterating */
 457         return 1;
 458 }
 459
 460 static void netvsc_drv_exit(void)
 461 {
 462         struct netvsc_driver *netvsc_drv_obj = &g_netvsc_drv.drv_obj;
 463         struct driver_context *drv_ctx = &g_netvsc_drv.drv_ctx;
 464         struct device *current_dev;
 465         int ret;
 466
 467         while (1) {
 468                 current_dev = NULL;
 469
 470                 /* Get the device */
 471                 ret = driver_for_each_device(&drv_ctx->driver, NULL,
 472                                              &current_dev, netvsc_drv_exit_cb);
 473                 if (ret)
 474                         DPRINT_WARN(NETVSC_DRV,
 475                                     "driver_for_each_device returned %d", ret);
 476
 477                 if (current_dev == NULL)
 478                         break;
 479
 480                 /* Initiate removal from the top-down */
 481                 DPRINT_INFO(NETVSC_DRV, "unregistering device (%p)...",
 482                             current_dev);
 483
 484                 device_unregister(current_dev);
 485         }
 486
 487         if (netvsc_drv_obj->base.OnCleanup)
 488                 netvsc_drv_obj->base.OnCleanup(&netvsc_drv_obj->base);
 489
 490         vmbus_child_driver_unregister(drv_ctx);
 491
 492         return;
 493 }
 494
 495 static int netvsc_drv_init(int (*drv_init)(struct hv_driver *drv))
 496 {
 497         struct netvsc_driver *net_drv_obj = &g_netvsc_drv.drv_obj;
 498         struct driver_context *drv_ctx = &g_netvsc_drv.drv_ctx;
 499         int ret;
 500
 501         net_drv_obj->ring_buf_size = ring_size * PAGE_SIZE;
 502         net_drv_obj->recv_cb = netvsc_recv_callback;
 503         net_drv_obj->link_status_change = netvsc_linkstatus_callback;
 504
 505         /* Callback to client driver to complete the initialization */
 506         drv_init(&net_drv_obj->base);
 507
 508         drv_ctx->driver.name = net_drv_obj->base.name;
 509         memcpy(&drv_ctx->class_id, &net_drv_obj->base.deviceType,
 510                sizeof(struct hv_guid));
 511
 512         drv_ctx->probe = netvsc_probe;
 513         drv_ctx->remove = netvsc_remove;
 514
 515         /* The driver belongs to vmbus */
 516         ret = vmbus_child_driver_register(drv_ctx);
 517
 518         return ret;
 519 }
 520
 521 static const struct dmi_system_id __initconst
 522 hv_netvsc_dmi_table[] __maybe_unused  = {
 523         {
 524                 .ident = "Hyper-V",
 525                 .matches = {
 526                         DMI_MATCH(DMI_SYS_VENDOR, "Microsoft Corporation"),
 527                         DMI_MATCH(DMI_PRODUCT_NAME, "Virtual Machine"),
 528                         DMI_MATCH(DMI_BOARD_NAME, "Virtual Machine"),
 529                 },
 530         },
 531         { },
 532 };
 533 MODULE_DEVICE_TABLE(dmi, hv_netvsc_dmi_table);
 534
 535 static int __init netvsc_init(void)
 536 {
 537         DPRINT_INFO(NETVSC_DRV, "Netvsc initializing....");
 538
 539         if (!dmi_check_system(hv_netvsc_dmi_table))
 540                 return -ENODEV;
 541
 542         return netvsc_drv_init(netvsc_initialize);
 543 }
 544
 545 static void __exit netvsc_exit(void)
 546 {
 547         netvsc_drv_exit();
 548 }
 549
 550 static const struct pci_device_id __initconst
 551 hv_netvsc_pci_table[] __maybe_unused = {
 552         { PCI_DEVICE(0x1414, 0x5353) }, /* VGA compatible controller */
 553         { 0 }
 554 };
 555 MODULE_DEVICE_TABLE(pci, hv_netvsc_pci_table);
 556
 557 MODULE_LICENSE("GPL");
 558 MODULE_VERSION(HV_DRV_VERSION);
 559 MODULE_DESCRIPTION("Microsoft Hyper-V network driver");
 560
 561 module_init(netvsc_init);
 562 module_exit(netvsc_exit);