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 <net/arp.h>
  33 #include <net/route.h>
  34 #include <net/sock.h>
  35 #include <net/pkt_sched.h>
  36 #include "osd.h"
  37 #include "logging.h"
  38 #include "vmbus.h"
  39 #include "NetVscApi.h"
  40
  41 MODULE_LICENSE("GPL");
  42
  43 struct net_device_context {
  44         /* point back to our device context */
  45         struct device_context *device_ctx;
  46         struct net_device_stats stats;
  47 };
  48
  49 struct netvsc_driver_context {
  50         /* !! These must be the first 2 fields !! */
  51         /* Which is a bug FIXME! */
  52         struct driver_context drv_ctx;
  53         struct netvsc_driver drv_obj;
  54 };
  55
  56 static int netvsc_ringbuffer_size = NETVSC_DEVICE_RING_BUFFER_SIZE;
  57
  58 /* The one and only one */
  59 static struct netvsc_driver_context g_netvsc_drv;
  60
  61 static struct net_device_stats *netvsc_get_stats(struct net_device *net)
  62 {
  63         struct net_device_context *net_device_ctx = netdev_priv(net);
  64
  65         return &net_device_ctx->stats;
  66 }
  67
  68 static void netvsc_set_multicast_list(struct net_device *net)
  69 {
  70 }
  71
  72 static int netvsc_open(struct net_device *net)
  73 {
  74         struct net_device_context *net_device_ctx = netdev_priv(net);
  75         struct driver_context *driver_ctx =
  76             driver_to_driver_context(net_device_ctx->device_ctx->device.driver);
  77         struct netvsc_driver_context *net_drv_ctx =
  78                 (struct netvsc_driver_context *)driver_ctx;
  79         struct netvsc_driver *net_drv_obj = &net_drv_ctx->drv_obj;
  80         struct hv_device *device_obj = &net_device_ctx->device_ctx->device_obj;
  81         int ret = 0;
  82
  83         DPRINT_ENTER(NETVSC_DRV);
  84
  85         if (netif_carrier_ok(net)) {
  86                 memset(&net_device_ctx->stats, 0,
  87                        sizeof(struct net_device_stats));
  88
  89                 /* Open up the device */
  90                 ret = net_drv_obj->OnOpen(device_obj);
  91                 if (ret != 0) {
  92                         DPRINT_ERR(NETVSC_DRV,
  93                                    "unable to open device (ret %d).", ret);
  94                         return ret;
  95                 }
  96
  97                 netif_start_queue(net);
  98         } else {
  99                 DPRINT_ERR(NETVSC_DRV, "unable to open device...link is down.");
 100         }
 101
 102         DPRINT_EXIT(NETVSC_DRV);
 103         return ret;
 104 }
 105
 106 static int netvsc_close(struct net_device *net)
 107 {
 108         struct net_device_context *net_device_ctx = netdev_priv(net);
 109         struct driver_context *driver_ctx =
 110             driver_to_driver_context(net_device_ctx->device_ctx->device.driver);
 111         struct netvsc_driver_context *net_drv_ctx =
 112                 (struct netvsc_driver_context *)driver_ctx;
 113         struct netvsc_driver *net_drv_obj = &net_drv_ctx->drv_obj;
 114         struct hv_device *device_obj = &net_device_ctx->device_ctx->device_obj;
 115         int ret;
 116
 117         DPRINT_ENTER(NETVSC_DRV);
 118
 119         netif_stop_queue(net);
 120
 121         ret = net_drv_obj->OnClose(device_obj);
 122         if (ret != 0)
 123                 DPRINT_ERR(NETVSC_DRV, "unable to close device (ret %d).", ret);
 124
 125         DPRINT_EXIT(NETVSC_DRV);
 126
 127         return ret;
 128 }
 129
 130 static void netvsc_xmit_completion(void *context)
 131 {
 132         struct hv_netvsc_packet *packet = (struct hv_netvsc_packet *)context;
 133         struct sk_buff *skb = (struct sk_buff *)
 134                 (unsigned long)packet->Completion.Send.SendCompletionTid;
 135         struct net_device *net;
 136
 137         DPRINT_ENTER(NETVSC_DRV);
 138
 139         kfree(packet);
 140
 141         if (skb) {
 142                 net = skb->dev;
 143                 dev_kfree_skb_any(skb);
 144
 145                 if (netif_queue_stopped(net)) {
 146                         DPRINT_INFO(NETVSC_DRV, "net device (%p) waking up...",
 147                                     net);
 148
 149                         netif_wake_queue(net);
 150                 }
 151         }
 152
 153         DPRINT_EXIT(NETVSC_DRV);
 154 }
 155
 156 static int netvsc_start_xmit(struct sk_buff *skb, struct net_device *net)
 157 {
 158         struct net_device_context *net_device_ctx = netdev_priv(net);
 159         struct driver_context *driver_ctx =
 160             driver_to_driver_context(net_device_ctx->device_ctx->device.driver);
 161         struct netvsc_driver_context *net_drv_ctx =
 162                 (struct netvsc_driver_context *)driver_ctx;
 163         struct netvsc_driver *net_drv_obj = &net_drv_ctx->drv_obj;
 164         struct hv_netvsc_packet *packet;
 165         int i;
 166         int ret;
 167         int num_frags;
 168         int retries = 0;
 169
 170         DPRINT_ENTER(NETVSC_DRV);
 171
 172         /* Support only 1 chain of frags */
 173         ASSERT(skb_shinfo(skb)->frag_list == NULL);
 174         ASSERT(skb->dev == net);
 175
 176         DPRINT_DBG(NETVSC_DRV, "xmit packet - len %d data_len %d",
 177                    skb->len, skb->data_len);
 178
 179         /* Add 1 for skb->data and any additional ones requested */
 180         num_frags = skb_shinfo(skb)->nr_frags + 1 +
 181                     net_drv_obj->AdditionalRequestPageBufferCount;
 182
 183         /* Allocate a netvsc packet based on # of frags. */
 184         packet = kzalloc(sizeof(struct hv_netvsc_packet) +
 185                          (num_frags * sizeof(struct hv_page_buffer)) +
 186                          net_drv_obj->RequestExtSize, GFP_ATOMIC);
 187         if (!packet) {
 188                 DPRINT_ERR(NETVSC_DRV, "unable to allocate hv_netvsc_packet");
 189                 return -1;
 190         }
 191
 192         packet->Extension = (void *)(unsigned long)packet +
 193                                 sizeof(struct hv_netvsc_packet) +
 194                                     (num_frags * sizeof(struct hv_page_buffer));
 195
 196         /* Setup the rndis header */
 197         packet->PageBufferCount = num_frags;
 198
 199         /* TODO: Flush all write buffers/ memory fence ??? */
 200         /* wmb(); */
 201
 202         /* Initialize it from the skb */
 203         ASSERT(skb->data);
 204         packet->TotalDataBufferLength   = skb->len;
 205
 206         /*
 207          * Start filling in the page buffers starting at
 208          * AdditionalRequestPageBufferCount offset
 209          */
 210         packet->PageBuffers[net_drv_obj->AdditionalRequestPageBufferCount].Pfn = virt_to_phys(skb->data) >> PAGE_SHIFT;
 211         packet->PageBuffers[net_drv_obj->AdditionalRequestPageBufferCount].Offset = (unsigned long)skb->data & (PAGE_SIZE - 1);
 212         packet->PageBuffers[net_drv_obj->AdditionalRequestPageBufferCount].Length = skb->len - skb->data_len;
 213
 214         ASSERT((skb->len - skb->data_len) <= PAGE_SIZE);
 215
 216         for (i = net_drv_obj->AdditionalRequestPageBufferCount + 1;
 217              i < num_frags; i++) {
 218                 packet->PageBuffers[i].Pfn =
 219                         page_to_pfn(skb_shinfo(skb)->frags[i-(net_drv_obj->AdditionalRequestPageBufferCount+1)].page);
 220                 packet->PageBuffers[i].Offset =
 221                         skb_shinfo(skb)->frags[i-(net_drv_obj->AdditionalRequestPageBufferCount+1)].page_offset;
 222                 packet->PageBuffers[i].Length =
 223                         skb_shinfo(skb)->frags[i-(net_drv_obj->AdditionalRequestPageBufferCount+1)].size;
 224         }
 225
 226         /* Set the completion routine */
 227         packet->Completion.Send.OnSendCompletion = netvsc_xmit_completion;
 228         packet->Completion.Send.SendCompletionContext = packet;
 229         packet->Completion.Send.SendCompletionTid = (unsigned long)skb;
 230
 231 retry_send:
 232         ret = net_drv_obj->OnSend(&net_device_ctx->device_ctx->device_obj,
 233                                   packet);
 234
 235         if (ret == 0) {
 236                 ret = NETDEV_TX_OK;
 237                 net_device_ctx->stats.tx_bytes += skb->len;
 238                 net_device_ctx->stats.tx_packets++;
 239         } else {
 240                 retries++;
 241                 if (retries < 4) {
 242                         DPRINT_ERR(NETVSC_DRV, "unable to send..."
 243                                         "retrying %d...", retries);
 244                         udelay(100);
 245                         goto retry_send;
 246                 }
 247
 248                 /* no more room or we are shutting down */
 249                 DPRINT_ERR(NETVSC_DRV, "unable to send (%d)..."
 250                            "marking net device (%p) busy", ret, net);
 251                 DPRINT_INFO(NETVSC_DRV, "net device (%p) stopping", net);
 252
 253                 ret = NETDEV_TX_BUSY;
 254                 net_device_ctx->stats.tx_dropped++;
 255
 256                 netif_stop_queue(net);
 257
 258                 /*
 259                  * Null it since the caller will free it instead of the
 260                  * completion routine
 261                  */
 262                 packet->Completion.Send.SendCompletionTid = 0;
 263
 264                 /*
 265                  * Release the resources since we will not get any send
 266                  * completion
 267                  */
 268                 netvsc_xmit_completion((void *)packet);
 269         }
 270
 271         DPRINT_DBG(NETVSC_DRV, "# of xmits %lu total size %lu",
 272                    net_device_ctx->stats.tx_packets,
 273                    net_device_ctx->stats.tx_bytes);
 274
 275         DPRINT_EXIT(NETVSC_DRV);
 276         return ret;
 277 }
 278
 279 /**
 280  * netvsc_linkstatus_callback - Link up/down notification
 281  */
 282 static void netvsc_linkstatus_callback(struct hv_device *device_obj,
 283                                        unsigned int status)
 284 {
 285         struct device_context *device_ctx = to_device_context(device_obj);
 286         struct net_device *net = dev_get_drvdata(&device_ctx->device);
 287
 288         DPRINT_ENTER(NETVSC_DRV);
 289
 290         if (!net) {
 291                 DPRINT_ERR(NETVSC_DRV, "got link status but net device "
 292                                 "not initialized yet");
 293                 return;
 294         }
 295
 296         if (status == 1) {
 297                 netif_carrier_on(net);
 298                 netif_wake_queue(net);
 299         } else {
 300                 netif_carrier_off(net);
 301                 netif_stop_queue(net);
 302         }
 303         DPRINT_EXIT(NETVSC_DRV);
 304 }
 305
 306 /**
 307  * netvsc_recv_callback -  Callback when we receive a packet from the "wire" on the specified device.
 308  */
 309 static int netvsc_recv_callback(struct hv_device *device_obj,
 310                                 struct hv_netvsc_packet *packet)
 311 {
 312         struct device_context *device_ctx = to_device_context(device_obj);
 313         struct net_device *net = dev_get_drvdata(&device_ctx->device);
 314         struct net_device_context *net_device_ctx;
 315         struct sk_buff *skb;
 316         void *data;
 317         int ret;
 318         int i;
 319         unsigned long flags;
 320
 321         DPRINT_ENTER(NETVSC_DRV);
 322
 323         if (!net) {
 324                 DPRINT_ERR(NETVSC_DRV, "got receive callback but net device "
 325                                 "not initialized yet");
 326                 return 0;
 327         }
 328
 329         net_device_ctx = netdev_priv(net);
 330
 331         /* Allocate a skb - TODO preallocate this */
 332         /* Pad 2-bytes to align IP header to 16 bytes */
 333         skb = dev_alloc_skb(packet->TotalDataBufferLength + 2);
 334         ASSERT(skb);
 335         skb_reserve(skb, 2);
 336         skb->dev = net;
 337
 338         /* for kmap_atomic */
 339         local_irq_save(flags);
 340
 341         /*
 342          * Copy to skb. This copy is needed here since the memory pointed by
 343          * hv_netvsc_packet cannot be deallocated
 344          */
 345         for (i = 0; i < packet->PageBufferCount; i++) {
 346                 data = kmap_atomic(pfn_to_page(packet->PageBuffers[i].Pfn),
 347                                                KM_IRQ1);
 348                 data = (void *)(unsigned long)data +
 349                                 packet->PageBuffers[i].Offset;
 350
 351                 memcpy(skb_put(skb, packet->PageBuffers[i].Length), data,
 352                        packet->PageBuffers[i].Length);
 353
 354                 kunmap_atomic((void *)((unsigned long)data -
 355                                        packet->PageBuffers[i].Offset), KM_IRQ1);
 356         }
 357
 358         local_irq_restore(flags);
 359
 360         skb->protocol = eth_type_trans(skb, net);
 361
 362         skb->ip_summed = CHECKSUM_NONE;
 363
 364         /*
 365          * Pass the skb back up. Network stack will deallocate the skb when it
 366          * is done
 367          */
 368         ret = netif_rx(skb);
 369
 370         switch (ret) {
 371         case NET_RX_DROP:
 372                 net_device_ctx->stats.rx_dropped++;
 373                 break;
 374         default:
 375                 net_device_ctx->stats.rx_packets++;
 376                 net_device_ctx->stats.rx_bytes += skb->len;
 377                 break;
 378
 379         }
 380         DPRINT_DBG(NETVSC_DRV, "# of recvs %lu total size %lu",
 381                    net_device_ctx->stats.rx_packets,
 382                    net_device_ctx->stats.rx_bytes);
 383
 384         DPRINT_EXIT(NETVSC_DRV);
 385
 386         return 0;
 387 }
 388
 389 static const struct net_device_ops device_ops = {
 390         .ndo_open =                     netvsc_open,
 391         .ndo_stop =                     netvsc_close,
 392         .ndo_start_xmit =               netvsc_start_xmit,
 393         .ndo_get_stats =                netvsc_get_stats,
 394         .ndo_set_multicast_list =       netvsc_set_multicast_list,
 395 };
 396
 397 static int netvsc_probe(struct device *device)
 398 {
 399         struct driver_context *driver_ctx =
 400                 driver_to_driver_context(device->driver);
 401         struct netvsc_driver_context *net_drv_ctx =
 402                 (struct netvsc_driver_context *)driver_ctx;
 403         struct netvsc_driver *net_drv_obj = &net_drv_ctx->drv_obj;
 404         struct device_context *device_ctx = device_to_device_context(device);
 405         struct hv_device *device_obj = &device_ctx->device_obj;
 406         struct net_device *net = NULL;
 407         struct net_device_context *net_device_ctx;
 408         struct netvsc_device_info device_info;
 409         int ret;
 410
 411         DPRINT_ENTER(NETVSC_DRV);
 412
 413         if (!net_drv_obj->Base.OnDeviceAdd)
 414                 return -1;
 415
 416         net = alloc_netdev(sizeof(struct net_device_context), "seth%d",
 417                            ether_setup);
 418         if (!net)
 419                 return -1;
 420
 421         /* Set initial state */
 422         netif_carrier_off(net);
 423         netif_stop_queue(net);
 424
 425         net_device_ctx = netdev_priv(net);
 426         net_device_ctx->device_ctx = device_ctx;
 427         dev_set_drvdata(device, net);
 428
 429         /* Notify the netvsc driver of the new device */
 430         ret = net_drv_obj->Base.OnDeviceAdd(device_obj, &device_info);
 431         if (ret != 0) {
 432                 free_netdev(net);
 433                 dev_set_drvdata(device, NULL);
 434
 435                 DPRINT_ERR(NETVSC_DRV, "unable to add netvsc device (ret %d)",
 436                            ret);
 437                 return ret;
 438         }
 439
 440         /*
 441          * If carrier is still off ie we did not get a link status callback,
 442          * update it if necessary
 443          */
 444         /*
 445          * FIXME: We should use a atomic or test/set instead to avoid getting
 446          * out of sync with the device's link status
 447          */
 448         if (!netif_carrier_ok(net))
 449                 if (!device_info.LinkState)
 450                         netif_carrier_on(net);
 451
 452         memcpy(net->dev_addr, device_info.MacAddr, ETH_ALEN);
 453
 454         net->netdev_ops = &device_ops;
 455
 456         SET_NETDEV_DEV(net, device);
 457
 458         ret = register_netdev(net);
 459         if (ret != 0) {
 460                 /* Remove the device and release the resource */
 461                 net_drv_obj->Base.OnDeviceRemove(device_obj);
 462                 free_netdev(net);
 463         }
 464
 465         DPRINT_EXIT(NETVSC_DRV);
 466         return ret;
 467 }
 468
 469 static int netvsc_remove(struct device *device)
 470 {
 471         struct driver_context *driver_ctx =
 472                 driver_to_driver_context(device->driver);
 473         struct netvsc_driver_context *net_drv_ctx =
 474                 (struct netvsc_driver_context *)driver_ctx;
 475         struct netvsc_driver *net_drv_obj = &net_drv_ctx->drv_obj;
 476         struct device_context *device_ctx = device_to_device_context(device);
 477         struct net_device *net = dev_get_drvdata(&device_ctx->device);
 478         struct hv_device *device_obj = &device_ctx->device_obj;
 479         int ret;
 480
 481         DPRINT_ENTER(NETVSC_DRV);
 482
 483         if (net == NULL) {
 484                 DPRINT_INFO(NETVSC, "no net device to remove");
 485                 DPRINT_EXIT(NETVSC_DRV);
 486                 return 0;
 487         }
 488
 489         if (!net_drv_obj->Base.OnDeviceRemove) {
 490                 DPRINT_EXIT(NETVSC_DRV);
 491                 return -1;
 492         }
 493
 494         /* Stop outbound asap */
 495         netif_stop_queue(net);
 496         /* netif_carrier_off(net); */
 497
 498         unregister_netdev(net);
 499
 500         /*
 501          * Call to the vsc driver to let it know that the device is being
 502          * removed
 503          */
 504         ret = net_drv_obj->Base.OnDeviceRemove(device_obj);
 505         if (ret != 0) {
 506                 /* TODO: */
 507                 DPRINT_ERR(NETVSC, "unable to remove vsc device (ret %d)", ret);
 508         }
 509
 510         free_netdev(net);
 511         DPRINT_EXIT(NETVSC_DRV);
 512         return ret;
 513 }
 514
 515 static int netvsc_drv_exit_cb(struct device *dev, void *data)
 516 {
 517         struct device **curr = (struct device **)data;
 518
 519         *curr = dev;
 520         /* stop iterating */
 521         return 1;
 522 }
 523
 524 static void netvsc_drv_exit(void)
 525 {
 526         struct netvsc_driver *netvsc_drv_obj = &g_netvsc_drv.drv_obj;
 527         struct driver_context *drv_ctx = &g_netvsc_drv.drv_ctx;
 528         struct device *current_dev;
 529         int ret;
 530
 531         DPRINT_ENTER(NETVSC_DRV);
 532
 533         while (1) {
 534                 current_dev = NULL;
 535
 536                 /* Get the device */
 537                 ret = driver_for_each_device(&drv_ctx->driver, NULL,
 538                                              &current_dev, netvsc_drv_exit_cb);
 539                 if (ret)
 540                         DPRINT_WARN(NETVSC_DRV,
 541                                     "driver_for_each_device returned %d", ret);
 542
 543                 if (current_dev == NULL)
 544                         break;
 545
 546                 /* Initiate removal from the top-down */
 547                 DPRINT_INFO(NETVSC_DRV, "unregistering device (%p)...",
 548                             current_dev);
 549
 550                 device_unregister(current_dev);
 551         }
 552
 553         if (netvsc_drv_obj->Base.OnCleanup)
 554                 netvsc_drv_obj->Base.OnCleanup(&netvsc_drv_obj->Base);
 555
 556         vmbus_child_driver_unregister(drv_ctx);
 557
 558         DPRINT_EXIT(NETVSC_DRV);
 559
 560         return;
 561 }
 562
 563 static int netvsc_drv_init(int (*drv_init)(struct hv_driver *drv))
 564 {
 565         struct netvsc_driver *net_drv_obj = &g_netvsc_drv.drv_obj;
 566         struct driver_context *drv_ctx = &g_netvsc_drv.drv_ctx;
 567         int ret;
 568
 569         DPRINT_ENTER(NETVSC_DRV);
 570
 571         vmbus_get_interface(&net_drv_obj->Base.VmbusChannelInterface);
 572
 573         net_drv_obj->RingBufferSize = netvsc_ringbuffer_size;
 574         net_drv_obj->OnReceiveCallback = netvsc_recv_callback;
 575         net_drv_obj->OnLinkStatusChanged = netvsc_linkstatus_callback;
 576
 577         /* Callback to client driver to complete the initialization */
 578         drv_init(&net_drv_obj->Base);
 579
 580         drv_ctx->driver.name = net_drv_obj->Base.name;
 581         memcpy(&drv_ctx->class_id, &net_drv_obj->Base.deviceType,
 582                sizeof(struct hv_guid));
 583
 584         drv_ctx->probe = netvsc_probe;
 585         drv_ctx->remove = netvsc_remove;
 586
 587         /* The driver belongs to vmbus */
 588         ret = vmbus_child_driver_register(drv_ctx);
 589
 590         DPRINT_EXIT(NETVSC_DRV);
 591
 592         return ret;
 593 }
 594
 595 static int __init netvsc_init(void)
 596 {
 597         int ret;
 598
 599         DPRINT_ENTER(NETVSC_DRV);
 600         DPRINT_INFO(NETVSC_DRV, "Netvsc initializing....");
 601
 602         ret = netvsc_drv_init(NetVscInitialize);
 603
 604         DPRINT_EXIT(NETVSC_DRV);
 605
 606         return ret;
 607 }
 608
 609 static void __exit netvsc_exit(void)
 610 {
 611         DPRINT_ENTER(NETVSC_DRV);
 612         netvsc_drv_exit();
 613         DPRINT_EXIT(NETVSC_DRV);
 614 }
 615
 616 module_param(netvsc_ringbuffer_size, int, S_IRUGO);
 617
 618 module_init(netvsc_init);
 619 module_exit(netvsc_exit);