Pileus Git - ~andy/linux/blob - drivers/staging/hv/netvsc_drv.c

   1 /*
   2  *
   3  * Copyright (c) 2009, Microsoft Corporation.
   4  *
   5  * This program is free software; you can redistribute it and/or modify it
   6  * under the terms and conditions of the GNU General Public License,
   7  * version 2, as published by the Free Software Foundation.
   8  *
   9  * This program is distributed in the hope it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  12  * more details.
  13  *
  14  * You should have received a copy of the GNU General Public License along with
  15  * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
  16  * Place - Suite 330, Boston, MA 02111-1307 USA.
  17  *
  18  * Authors:
  19  *   Hank Janssen  <hjanssen@microsoft.com>
  20  *
  21  */
  22
  23
  24 #include <linux/init.h>
  25 #include <linux/module.h>
  26 #include <linux/highmem.h>
  27 #include <linux/device.h>
  28 #if defined(KERNEL_2_6_5) || defined(KERNEL_2_6_9)
  29 #include <asm/io.h>
  30 #else
  31 #include <linux/io.h>
  32 #endif
  33 #include <linux/delay.h>
  34 #include <linux/netdevice.h>
  35 #include <linux/inetdevice.h>
  36 #include <linux/etherdevice.h>
  37 #include <linux/skbuff.h>
  38 #include <linux/in.h>
  39 #include <net/arp.h>
  40 #include <net/route.h>
  41 #include <net/sock.h>
  42 #include <net/pkt_sched.h>
  43
  44 #include "logging.h"
  45 #include "vmbus.h"
  46
  47 #include "NetVscApi.h"
  48
  49 MODULE_LICENSE("GPL");
  50
  51 //
  52 // Static decl
  53 //
  54 static int netvsc_probe(struct device *device);
  55 static int netvsc_remove(struct device *device);
  56 static int netvsc_open(struct net_device *net);
  57 static void netvsc_xmit_completion(void *context);
  58 static int netvsc_start_xmit (struct sk_buff *skb, struct net_device *net);
  59 static int netvsc_recv_callback(DEVICE_OBJECT *device_obj, NETVSC_PACKET* Packet);
  60 static int netvsc_close(struct net_device *net);
  61 static struct net_device_stats *netvsc_get_stats(struct net_device *net);
  62 static void netvsc_linkstatus_callback(DEVICE_OBJECT *device_obj, unsigned int status);
  63
  64 //
  65 // Data types
  66 //
  67 struct net_device_context {
  68         struct device_context   *device_ctx; // point back to our device context
  69         struct net_device_stats stats;
  70 };
  71
  72 struct netvsc_driver_context {
  73         // !! These must be the first 2 fields !!
  74         struct driver_context   drv_ctx;
  75         NETVSC_DRIVER_OBJECT    drv_obj;
  76 };
  77
  78 //
  79 // Globals
  80 //
  81
  82 static int netvsc_ringbuffer_size = NETVSC_DEVICE_RING_BUFFER_SIZE;
  83
  84 // The one and only one
  85 static struct netvsc_driver_context g_netvsc_drv;
  86
  87 //
  88 // Routines
  89 //
  90
  91 /*++
  92
  93 Name:   netvsc_drv_init()
  94
  95 Desc:   NetVsc driver initialization
  96
  97 --*/
  98 int netvsc_drv_init(PFN_DRIVERINITIALIZE pfn_drv_init)
  99 {
 100         int ret=0;
 101         NETVSC_DRIVER_OBJECT *net_drv_obj=&g_netvsc_drv.drv_obj;
 102         struct driver_context *drv_ctx=&g_netvsc_drv.drv_ctx;
 103
 104         DPRINT_ENTER(NETVSC_DRV);
 105
 106         vmbus_get_interface(&net_drv_obj->Base.VmbusChannelInterface);
 107
 108         net_drv_obj->RingBufferSize = netvsc_ringbuffer_size;
 109         net_drv_obj->OnReceiveCallback = netvsc_recv_callback;
 110         net_drv_obj->OnLinkStatusChanged = netvsc_linkstatus_callback;
 111
 112         // Callback to client driver to complete the initialization
 113         pfn_drv_init(&net_drv_obj->Base);
 114
 115         drv_ctx->driver.name = net_drv_obj->Base.name;
 116         memcpy(&drv_ctx->class_id, &net_drv_obj->Base.deviceType, sizeof(GUID));
 117
 118 #if defined(KERNEL_2_6_5) || defined(KERNEL_2_6_9)
 119         drv_ctx->driver.probe = netvsc_probe;
 120         drv_ctx->driver.remove = netvsc_remove;
 121 #else
 122         drv_ctx->probe = netvsc_probe;
 123         drv_ctx->remove = netvsc_remove;
 124 #endif
 125
 126         // The driver belongs to vmbus
 127         vmbus_child_driver_register(drv_ctx);
 128
 129         DPRINT_EXIT(NETVSC_DRV);
 130
 131         return ret;
 132 }
 133
 134 /*++
 135
 136 Name:   netvsc_get_stats()
 137
 138 Desc:   Get the network stats
 139
 140 --*/
 141 static struct net_device_stats *netvsc_get_stats(struct net_device *net)
 142 {
 143         struct net_device_context *net_device_ctx = netdev_priv(net);
 144
 145         return &net_device_ctx->stats;
 146 }
 147
 148 /*++
 149
 150 Name:   netvsc_set_multicast_list()
 151
 152 Desc:   Set the multicast list
 153
 154 Remark: No-op here
 155 --*/
 156 static void netvsc_set_multicast_list(UNUSED_VAR(struct net_device *net))
 157 {
 158 }
 159
 160
 161 /*++
 162
 163 Name:   netvsc_probe()
 164
 165 Desc:   Add the specified new device to this driver
 166
 167 --*/
 168 static int netvsc_probe(struct device *device)
 169 {
 170         int ret=0;
 171
 172         struct driver_context *driver_ctx = driver_to_driver_context(device->driver);
 173         struct netvsc_driver_context *net_drv_ctx = (struct netvsc_driver_context*)driver_ctx;
 174         NETVSC_DRIVER_OBJECT *net_drv_obj = &net_drv_ctx->drv_obj;
 175
 176         struct device_context *device_ctx = device_to_device_context(device);
 177         DEVICE_OBJECT *device_obj = &device_ctx->device_obj;
 178
 179         struct net_device *net = NULL;
 180         struct net_device_context *net_device_ctx;
 181         NETVSC_DEVICE_INFO device_info;
 182
 183         DPRINT_ENTER(NETVSC_DRV);
 184
 185         if (!net_drv_obj->Base.OnDeviceAdd)
 186         {
 187                 return -1;
 188         }
 189
 190         net = alloc_netdev(sizeof(struct net_device_context), "seth%d", ether_setup);
 191         //net = alloc_etherdev(sizeof(struct net_device_context));
 192         if (!net)
 193         {
 194                 return -1;
 195         }
 196
 197         // Set initial state
 198         netif_carrier_off(net);
 199         netif_stop_queue(net);
 200
 201         net_device_ctx = netdev_priv(net);
 202         net_device_ctx->device_ctx = device_ctx;
 203         device->driver_data = net;
 204
 205         // Notify the netvsc driver of the new device
 206         ret = net_drv_obj->Base.OnDeviceAdd(device_obj, (void*)&device_info);
 207         if (ret != 0)
 208         {
 209                 free_netdev(net);
 210                 device->driver_data = NULL;
 211
 212                 DPRINT_ERR(NETVSC_DRV, "unable to add netvsc device (ret %d)", ret);
 213                 return ret;
 214         }
 215
 216         // If carrier is still off ie we did not get a link status callback, update it if necessary
 217         // FIXME: We should use a atomic or test/set instead to avoid getting out of sync with the device's link status
 218         if (!netif_carrier_ok(net))
 219         {
 220                 if (!device_info.LinkState)
 221                 {
 222                         netif_carrier_on(net);
 223                 }
 224         }
 225
 226         memcpy(net->dev_addr, device_info.MacAddr, ETH_ALEN);
 227
 228         net->open                               = netvsc_open;
 229         net->hard_start_xmit    = netvsc_start_xmit;
 230         net->stop                               = netvsc_close;
 231         net->get_stats                  = netvsc_get_stats;
 232         net->set_multicast_list = netvsc_set_multicast_list;
 233
 234 #if !defined(KERNEL_2_6_27)
 235         SET_MODULE_OWNER(net);
 236 #endif
 237         SET_NETDEV_DEV(net, device);
 238
 239         ret = register_netdev(net);
 240         if (ret != 0)
 241         {
 242                 // Remove the device and release the resource
 243                 net_drv_obj->Base.OnDeviceRemove(device_obj);
 244                 free_netdev(net);
 245         }
 246
 247         DPRINT_EXIT(NETVSC_DRV);
 248
 249         return ret;
 250 }
 251
 252 static int netvsc_remove(struct device *device)
 253 {
 254         int ret=0;
 255         struct driver_context *driver_ctx = driver_to_driver_context(device->driver);
 256         struct netvsc_driver_context *net_drv_ctx = (struct netvsc_driver_context*)driver_ctx;
 257         NETVSC_DRIVER_OBJECT *net_drv_obj = &net_drv_ctx->drv_obj;
 258
 259         struct device_context *device_ctx = device_to_device_context(device);
 260         struct net_device *net = (struct net_device *)device_ctx->device.driver_data;
 261         DEVICE_OBJECT *device_obj = &device_ctx->device_obj;
 262
 263         DPRINT_ENTER(NETVSC_DRV);
 264
 265         if (net == NULL)
 266         {
 267                 DPRINT_INFO(NETVSC, "no net device to remove");
 268                 DPRINT_EXIT(NETVSC_DRV);
 269                 return 0;
 270         }
 271
 272         if (!net_drv_obj->Base.OnDeviceRemove)
 273         {
 274                 DPRINT_EXIT(NETVSC_DRV);
 275                 return -1;
 276         }
 277
 278         // Stop outbound asap
 279         netif_stop_queue(net);
 280         //netif_carrier_off(net);
 281
 282         unregister_netdev(net);
 283
 284         // Call to the vsc driver to let it know that the device is being removed
 285         ret = net_drv_obj->Base.OnDeviceRemove(device_obj);
 286         if (ret != 0)
 287         {
 288                 // TODO:
 289                 DPRINT_ERR(NETVSC, "unable to remove vsc device (ret %d)", ret);
 290         }
 291
 292         free_netdev(net);
 293
 294         DPRINT_EXIT(NETVSC_DRV);
 295
 296         return ret;
 297 }
 298
 299 /*++
 300
 301 Name:   netvsc_open()
 302
 303 Desc:   Open the specified interface device
 304
 305 --*/
 306 static int netvsc_open(struct net_device *net)
 307 {
 308         int ret=0;
 309         struct net_device_context *net_device_ctx = netdev_priv(net);
 310         struct driver_context *driver_ctx = driver_to_driver_context(net_device_ctx->device_ctx->device.driver);
 311         struct netvsc_driver_context *net_drv_ctx = (struct netvsc_driver_context*)driver_ctx;
 312         NETVSC_DRIVER_OBJECT *net_drv_obj = &net_drv_ctx->drv_obj;
 313
 314         DEVICE_OBJECT *device_obj = &net_device_ctx->device_ctx->device_obj;
 315
 316         DPRINT_ENTER(NETVSC_DRV);
 317
 318         if (netif_carrier_ok(net))
 319         {
 320                 memset(&net_device_ctx->stats, 0 , sizeof(struct net_device_stats));
 321
 322                 // Open up the device
 323                 ret = net_drv_obj->OnOpen(device_obj);
 324                 if (ret != 0)
 325                 {
 326                         DPRINT_ERR(NETVSC_DRV, "unable to open device (ret %d).", ret);
 327                         return ret;
 328                 }
 329
 330                 netif_start_queue(net);
 331         }
 332         else
 333         {
 334                 DPRINT_ERR(NETVSC_DRV, "unable to open device...link is down.");
 335         }
 336
 337         DPRINT_EXIT(NETVSC_DRV);
 338         return ret;
 339 }
 340
 341 /*++
 342
 343 Name:   netvsc_close()
 344
 345 Desc:   Close the specified interface device
 346
 347 --*/
 348 static int netvsc_close(struct net_device *net)
 349 {
 350         int ret=0;
 351         struct net_device_context *net_device_ctx = netdev_priv(net);
 352         struct driver_context *driver_ctx = driver_to_driver_context(net_device_ctx->device_ctx->device.driver);
 353         struct netvsc_driver_context *net_drv_ctx = (struct netvsc_driver_context*)driver_ctx;
 354         NETVSC_DRIVER_OBJECT *net_drv_obj = &net_drv_ctx->drv_obj;
 355
 356         DEVICE_OBJECT *device_obj = &net_device_ctx->device_ctx->device_obj;
 357
 358         DPRINT_ENTER(NETVSC_DRV);
 359
 360         netif_stop_queue(net);
 361
 362         ret = net_drv_obj->OnClose(device_obj);
 363         if (ret != 0)
 364         {
 365                 DPRINT_ERR(NETVSC_DRV, "unable to close device (ret %d).", ret);
 366         }
 367
 368         DPRINT_EXIT(NETVSC_DRV);
 369
 370         return ret;
 371 }
 372
 373
 374 /*++
 375
 376 Name:   netvsc_xmit_completion()
 377
 378 Desc:   Send completion processing
 379
 380 --*/
 381 static void netvsc_xmit_completion(void *context)
 382 {
 383         NETVSC_PACKET *packet = (NETVSC_PACKET *)context;
 384         struct sk_buff *skb = (struct sk_buff *)(ULONG_PTR)packet->Completion.Send.SendCompletionTid;
 385         struct net_device* net;
 386
 387         DPRINT_ENTER(NETVSC_DRV);
 388
 389         kfree(packet);
 390
 391         if (skb)
 392         {
 393                 net = skb->dev;
 394
 395                 dev_kfree_skb_any(skb);
 396
 397                 if (netif_queue_stopped(net))
 398                 {
 399                         DPRINT_INFO(NETVSC_DRV, "net device (%p) waking up...", net);
 400
 401                         netif_wake_queue(net);
 402                 }
 403         }
 404
 405         DPRINT_EXIT(NETVSC_DRV);
 406 }
 407
 408 /*++
 409
 410 Name:   netvsc_start_xmit()
 411
 412 Desc:   Start a send
 413
 414 --*/
 415 static int netvsc_start_xmit (struct sk_buff *skb, struct net_device *net)
 416 {
 417         int ret=0;
 418         struct net_device_context *net_device_ctx = netdev_priv(net);
 419         struct driver_context *driver_ctx = driver_to_driver_context(net_device_ctx->device_ctx->device.driver);
 420         struct netvsc_driver_context *net_drv_ctx = (struct netvsc_driver_context*)driver_ctx;
 421         NETVSC_DRIVER_OBJECT *net_drv_obj = &net_drv_ctx->drv_obj;
 422
 423         int i=0;
 424         NETVSC_PACKET* packet;
 425         int num_frags;
 426         int retries=0;
 427
 428         DPRINT_ENTER(NETVSC_DRV);
 429
 430         // Support only 1 chain of frags
 431         ASSERT(skb_shinfo(skb)->frag_list == NULL);
 432         ASSERT(skb->dev == net);
 433
 434         DPRINT_DBG(NETVSC_DRV, "xmit packet - len %d data_len %d", skb->len, skb->data_len);
 435
 436         // Add 1 for skb->data and any additional ones requested
 437         num_frags = skb_shinfo(skb)->nr_frags + 1 + net_drv_obj->AdditionalRequestPageBufferCount;
 438
 439         // Allocate a netvsc packet based on # of frags.
 440         packet = kzalloc(sizeof(NETVSC_PACKET) + (num_frags * sizeof(PAGE_BUFFER)) + net_drv_obj->RequestExtSize, GFP_ATOMIC);
 441         if (!packet)
 442         {
 443                 DPRINT_ERR(NETVSC_DRV, "unable to allocate NETVSC_PACKET");
 444                 return -1;
 445         }
 446
 447         packet->Extension = (void*)(unsigned long)packet + sizeof(NETVSC_PACKET) + (num_frags * sizeof(PAGE_BUFFER)) ;
 448
 449         // Setup the rndis header
 450         packet->PageBufferCount = num_frags;
 451
 452         // TODO: Flush all write buffers/ memory fence ???
 453         //wmb();
 454
 455         // Initialize it from the skb
 456         ASSERT(skb->data);
 457         packet->TotalDataBufferLength   = skb->len;
 458
 459         // Start filling in the page buffers starting at AdditionalRequestPageBufferCount offset
 460         packet->PageBuffers[net_drv_obj->AdditionalRequestPageBufferCount].Pfn          = virt_to_phys(skb->data) >> PAGE_SHIFT;
 461         packet->PageBuffers[net_drv_obj->AdditionalRequestPageBufferCount].Offset       = (unsigned long)skb->data & (PAGE_SIZE -1);
 462         packet->PageBuffers[net_drv_obj->AdditionalRequestPageBufferCount].Length       = skb->len - skb->data_len;
 463
 464         ASSERT((skb->len - skb->data_len) <= PAGE_SIZE);
 465
 466         for (i=net_drv_obj->AdditionalRequestPageBufferCount+1; i<num_frags; i++)
 467         {
 468                 packet->PageBuffers[i].Pfn              = page_to_pfn(skb_shinfo(skb)->frags[i-(net_drv_obj->AdditionalRequestPageBufferCount+1)].page);
 469                 packet->PageBuffers[i].Offset   = skb_shinfo(skb)->frags[i-(net_drv_obj->AdditionalRequestPageBufferCount+1)].page_offset;
 470                 packet->PageBuffers[i].Length   = skb_shinfo(skb)->frags[i-(net_drv_obj->AdditionalRequestPageBufferCount+1)].size;
 471         }
 472
 473         // Set the completion routine
 474         packet->Completion.Send.OnSendCompletion = netvsc_xmit_completion;
 475         packet->Completion.Send.SendCompletionContext = packet;
 476         packet->Completion.Send.SendCompletionTid = (ULONG_PTR)skb;
 477
 478 retry_send:
 479         ret = net_drv_obj->OnSend(&net_device_ctx->device_ctx->device_obj, packet);
 480
 481         if (ret == 0)
 482         {
 483 #ifdef KERNEL_2_6_5
 484 #define NETDEV_TX_OK    0
 485 #define NETDEV_TX_BUSY  0
 486 #endif
 487                 ret = NETDEV_TX_OK;
 488                 net_device_ctx->stats.tx_bytes += skb->len;
 489                 net_device_ctx->stats.tx_packets++;
 490         }
 491         else
 492         {
 493                 retries++;
 494                 if (retries < 4)
 495                 {
 496                         DPRINT_ERR(NETVSC_DRV, "unable to send...retrying %d...", retries);
 497                         udelay(100);
 498                         goto retry_send;
 499                 }
 500
 501                 // no more room or we are shutting down
 502                 DPRINT_ERR(NETVSC_DRV, "unable to send (%d)...marking net device (%p) busy", ret, net);
 503                 DPRINT_INFO(NETVSC_DRV, "net device (%p) stopping", net);
 504
 505                 ret = NETDEV_TX_BUSY;
 506                 net_device_ctx->stats.tx_dropped++;
 507
 508                 netif_stop_queue(net);
 509
 510                 // Null it since the caller will free it instead of the completion routine
 511                 packet->Completion.Send.SendCompletionTid = 0;
 512
 513                 // Release the resources since we will not get any send completion
 514                 netvsc_xmit_completion((void*)packet);
 515         }
 516
 517         DPRINT_DBG(NETVSC_DRV, "# of xmits %lu total size %lu", net_device_ctx->stats.tx_packets, net_device_ctx->stats.tx_bytes);
 518
 519         DPRINT_EXIT(NETVSC_DRV);
 520         return ret;
 521 }
 522
 523
 524 /*++
 525
 526 Name:   netvsc_linkstatus_callback()
 527
 528 Desc:   Link up/down notification
 529
 530 --*/
 531 static void netvsc_linkstatus_callback(DEVICE_OBJECT *device_obj, unsigned int status)
 532 {
 533         struct device_context* device_ctx = to_device_context(device_obj);
 534         struct net_device* net = (struct net_device *)device_ctx->device.driver_data;
 535
 536         DPRINT_ENTER(NETVSC_DRV);
 537
 538         if (!net)
 539         {
 540                 DPRINT_ERR(NETVSC_DRV, "got link status but net device not initialized yet");
 541                 return;
 542         }
 543
 544         if (status == 1)
 545         {
 546                 netif_carrier_on(net);
 547                 netif_wake_queue(net);
 548         }
 549         else
 550         {
 551                 netif_carrier_off(net);
 552                 netif_stop_queue(net);
 553         }
 554         DPRINT_EXIT(NETVSC_DRV);
 555 }
 556
 557
 558 /*++
 559
 560 Name:   netvsc_recv_callback()
 561
 562 Desc:   Callback when we receive a packet from the "wire" on the specify device
 563
 564 --*/
 565 static int netvsc_recv_callback(DEVICE_OBJECT *device_obj, NETVSC_PACKET* packet)
 566 {
 567         int ret=0;
 568         struct device_context *device_ctx = to_device_context(device_obj);
 569         struct net_device *net = (struct net_device *)device_ctx->device.driver_data;
 570         struct net_device_context *net_device_ctx;
 571
 572         struct sk_buff *skb;
 573         void *data;
 574         int i=0;
 575         unsigned long flags;
 576
 577         DPRINT_ENTER(NETVSC_DRV);
 578
 579         if (!net)
 580         {
 581                 DPRINT_ERR(NETVSC_DRV, "got receive callback but net device not initialized yet");
 582                 return 0;
 583         }
 584
 585         net_device_ctx = netdev_priv(net);
 586
 587         // Allocate a skb - TODO preallocate this
 588         //skb = alloc_skb(packet->TotalDataBufferLength, GFP_ATOMIC);
 589         skb = dev_alloc_skb(packet->TotalDataBufferLength + 2); // Pad 2-bytes to align IP header to 16 bytes
 590         ASSERT(skb);
 591         skb_reserve(skb, 2);
 592         skb->dev = net;
 593
 594         // for kmap_atomic
 595         local_irq_save(flags);
 596
 597         // Copy to skb. This copy is needed here since the memory pointed by NETVSC_PACKET
 598         // cannot be deallocated
 599         for (i=0; i<packet->PageBufferCount; i++)
 600         {
 601             data = kmap_atomic(pfn_to_page(packet->PageBuffers[i].Pfn), KM_IRQ1);
 602             data = (void*)(unsigned long)data + packet->PageBuffers[i].Offset;
 603
 604             memcpy(skb_put(skb, packet->PageBuffers[i].Length), data, packet->PageBuffers[i].Length);
 605
 606             kunmap_atomic((void*)((unsigned long)data - packet->PageBuffers[i].Offset), KM_IRQ1);
 607         }
 608
 609         local_irq_restore(flags);
 610
 611         skb->protocol = eth_type_trans(skb, net);
 612
 613         skb->ip_summed = CHECKSUM_NONE;
 614
 615         // Pass the skb back up. Network stack will deallocate the skb when it is done
 616         ret = netif_rx(skb);
 617
 618         switch (ret)
 619         {
 620         case NET_RX_DROP:
 621                 net_device_ctx->stats.rx_dropped++;
 622                 break;
 623         default:
 624                 net_device_ctx->stats.rx_packets++;
 625                 net_device_ctx->stats.rx_bytes += skb->len;
 626                 break;
 627
 628         }
 629         DPRINT_DBG(NETVSC_DRV, "# of recvs %lu total size %lu", net_device_ctx->stats.rx_packets, net_device_ctx->stats.rx_bytes);
 630
 631         DPRINT_EXIT(NETVSC_DRV);
 632
 633         return 0;
 634 }
 635
 636 static int netvsc_drv_exit_cb(struct device *dev, void *data)
 637 {
 638         struct device **curr = (struct device **)data;
 639         *curr = dev;
 640         return 1; // stop iterating
 641 }
 642
 643 /*++
 644
 645 Name:   netvsc_drv_exit()
 646
 647 Desc:
 648
 649 --*/
 650 void netvsc_drv_exit(void)
 651 {
 652         NETVSC_DRIVER_OBJECT *netvsc_drv_obj=&g_netvsc_drv.drv_obj;
 653         struct driver_context *drv_ctx=&g_netvsc_drv.drv_ctx;
 654
 655         struct device *current_dev=NULL;
 656 #if defined(KERNEL_2_6_5) || defined(KERNEL_2_6_9)
 657 #define driver_for_each_device(drv, start, data, fn) \
 658         struct list_head *ptr, *n; \
 659         list_for_each_safe(ptr, n, &((drv)->devices)) {\
 660                 struct device *curr_dev;\
 661                 curr_dev = list_entry(ptr, struct device, driver_list);\
 662                 fn(curr_dev, data);\
 663         }
 664 #endif
 665
 666         DPRINT_ENTER(NETVSC_DRV);
 667
 668         while (1)
 669         {
 670                 current_dev = NULL;
 671
 672                 // Get the device
 673                 driver_for_each_device(&drv_ctx->driver, NULL, (void*)&current_dev, netvsc_drv_exit_cb);
 674
 675                 if (current_dev == NULL)
 676                         break;
 677
 678                 // Initiate removal from the top-down
 679                 DPRINT_INFO(NETVSC_DRV, "unregistering device (%p)...", current_dev);
 680
 681                 device_unregister(current_dev);
 682         }
 683
 684         if (netvsc_drv_obj->Base.OnCleanup)
 685                 netvsc_drv_obj->Base.OnCleanup(&netvsc_drv_obj->Base);
 686
 687         vmbus_child_driver_unregister(drv_ctx);
 688
 689         DPRINT_EXIT(NETVSC_DRV);
 690
 691         return;
 692 }
 693
 694 static int __init netvsc_init(void)
 695 {
 696         int ret;
 697
 698         DPRINT_ENTER(NETVSC_DRV);
 699         DPRINT_INFO(NETVSC_DRV, "Netvsc initializing....");
 700
 701         ret = netvsc_drv_init(NetVscInitialize);
 702
 703         DPRINT_EXIT(NETVSC_DRV);
 704
 705         return ret;
 706 }
 707
 708 static void __exit netvsc_exit(void)
 709 {
 710         DPRINT_ENTER(NETVSC_DRV);
 711
 712         netvsc_drv_exit();
 713
 714         DPRINT_EXIT(NETVSC_DRV);
 715 }
 716
 717 module_param(netvsc_ringbuffer_size, int, S_IRUGO);
 718
 719 module_init(netvsc_init);
 720 module_exit(netvsc_exit);