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