palacios/src/devices/lnx_virtio_vnet.c

   1 /*
   2  * This file is part of the Palacios Virtual Machine Monitor developed
   3  * by the V3VEE Project with funding from the United States National
   4  * Science Foundation and the Department of Energy.
   5  *
   6  * The V3VEE Project is a joint project between Northwestern University
   7  * and the University of New Mexico.  You can find out more at
   8  * http://www.v3vee.org
   9  *
  10  * Copyright (c) 2008, Jack Lange <jarusl@cs.northwestern.edu>
  11  * Copyright (c) 2008, Lei Xia <lxia@cs.northwestern.edu>
  12  * Copyright (c) 2008, The V3VEE Project <http://www.v3vee.org>
  13  * All rights reserved.
  14  *
  15  * Author: Jack Lange <jarusl@cs.northwestern.edu>
  16  *             Lei Xia <lxia@cs.northwestern.edu>
  17  *
  18  * This is free software.  You are permitted to use,
  19  * redistribute, and modify it as specified in the file "V3VEE_LICENSE".
  20  */
  21
  22 #include <palacios/vmm.h>
  23 #include <palacios/vmm_dev_mgr.h>
  24 #include <palacios/vm_guest_mem.h>
  25 #include <devices/lnx_virtio_pci.h>
  26 #include <palacios/vmm_vnet.h>
  27 #include <palacios/vmm_sprintf.h>
  28 #include <devices/pci.h>
  29
  30
  31 #ifndef CONFIG_DEBUG_LINUX_VIRTIO_VNET
  32 #undef PrintDebug
  33 #define PrintDebug(fmt, args...)
  34 #endif
  35
  36
  37 #define QUEUE_SIZE 4096
  38 #define CMD_QUEUE_SIZE 128
  39 #define NUM_QUEUES 3
  40
  41 struct vnet_config {
  42     uint32_t num_devs;
  43     uint32_t num_routes;
  44 } __attribute__((packed));
  45
  46
  47 #define CTRL_QUEUE 0
  48 #define XMIT_QUEUE 1
  49 #define RECV_QUEUE 2
  50
  51 struct virtio_vnet_state {
  52     struct v3_vm_info * vm;
  53     struct vnet_config vnet_cfg;
  54     struct virtio_config virtio_cfg;
  55
  56     struct vm_device * pci_bus;
  57     struct pci_device * pci_dev;
  58
  59     struct virtio_queue queue[NUM_QUEUES];
  60
  61     struct virtio_queue * cur_queue;
  62
  63     int io_range_size;
  64     v3_lock_t lock;
  65
  66     ulong_t pkt_sent, pkt_recv, pkt_drop, tx_exit, rx_exit, total_exit;
  67     int ready;
  68 };
  69
  70 #define VNET_GET_ROUTES 10
  71 #define VNET_ADD_ROUTE 11
  72 #define VNET_DEL_ROUTE 12
  73
  74 #define VNET_GET_LINKS 20
  75 #define VNET_ADD_LINK 21
  76 #define VNET_DEL_LINK 22
  77
  78 // structure of the vnet command header
  79 struct vnet_ctrl_hdr {
  80     uint8_t cmd_type;
  81     uint32_t num_cmds;
  82 } __attribute__((packed));
  83
  84
  85 struct vnet_bridge_pkt {
  86     uint32_t link_id;
  87     uint32_t pkt_size;
  88     uint8_t pkt[ETHERNET_PACKET_LEN];
  89 }__attribute__((packed));
  90
  91
  92 static int virtio_reset(struct virtio_vnet_state * vnet_state) {
  93
  94     memset(vnet_state->queue, 0, sizeof(struct virtio_queue) * NUM_QUEUES);
  95
  96     vnet_state->cur_queue = &(vnet_state->queue[0]);
  97
  98     vnet_state->virtio_cfg.status = 0;
  99     vnet_state->virtio_cfg.pci_isr = 0;
 100
 101     vnet_state->queue[0].queue_size = CMD_QUEUE_SIZE;
 102     vnet_state->queue[1].queue_size = QUEUE_SIZE;
 103     vnet_state->queue[2].queue_size = QUEUE_SIZE;
 104
 105     memset(&(vnet_state->vnet_cfg), 0, sizeof(struct vnet_config));
 106     v3_lock_init(&(vnet_state->lock));
 107
 108     return 0;
 109 }
 110
 111
 112
 113 static int get_desc_count(struct virtio_queue * q, int index) {
 114     struct vring_desc * tmp_desc = &(q->desc[index]);
 115     int cnt = 1;
 116
 117     while (tmp_desc->flags & VIRTIO_NEXT_FLAG) {
 118         tmp_desc = &(q->desc[tmp_desc->next]);
 119         cnt++;
 120     }
 121
 122     return cnt;
 123 }
 124
 125
 126
 127
 128 static int handle_cmd_kick(struct guest_info * core, struct virtio_vnet_state * vnet_state) {
 129     struct virtio_queue * q = &(vnet_state->queue[0]);
 130
 131     PrintDebug("VNET Bridge: Handling command  queue\n");
 132
 133     while (q->cur_avail_idx != q->avail->index) {
 134         struct vring_desc * hdr_desc = NULL;
 135         struct vring_desc * buf_desc = NULL;
 136         struct vring_desc * status_desc = NULL;
 137         uint16_t desc_idx = q->avail->ring[q->cur_avail_idx % QUEUE_SIZE];
 138         uint16_t desc_cnt = get_desc_count(q, desc_idx);
 139         struct vnet_ctrl_hdr * hdr = NULL;
 140         int i;
 141         int xfer_len = 0;
 142         uint8_t * status_ptr = NULL;
 143         uint8_t status = 0;
 144
 145
 146         PrintDebug("VNET Bridge: CMD: Descriptor Count=%d, index=%d, desc_idx=%d\n", desc_cnt, q->cur_avail_idx % QUEUE_SIZE, desc_idx);
 147
 148         if (desc_cnt < 3) {
 149             PrintError("VNET Bridge cmd must include at least 3 descriptors (cnt=%d)\n", desc_cnt);
 150             return -1;
 151         }
 152
 153         hdr_desc = &(q->desc[desc_idx]);
 154
 155         if (v3_gpa_to_hva(core, hdr_desc->addr_gpa, (addr_t *)&hdr) == -1) {
 156             PrintError("Could not translate VirtioVNET header address\n");
 157             return -1;
 158         }
 159
 160         desc_idx = hdr_desc->next;
 161
 162         if (hdr->cmd_type == VNET_ADD_ROUTE) {
 163
 164             for (i = 0; i < hdr->num_cmds; i++) {
 165                 uint8_t tmp_status = 0;
 166                 struct v3_vnet_route * route = NULL;
 167
 168                 buf_desc = &(q->desc[desc_idx]);
 169
 170                 if (v3_gpa_to_hva(core, buf_desc->addr_gpa, (addr_t *)&(route)) == -1) {
 171                     PrintError("Could not translate route address\n");
 172                     return -1;
 173                 }
 174
 175                 // add route
 176                 PrintDebug("VNET Bridge: Adding VNET Route\n");
 177
 178                 tmp_status = v3_vnet_add_route(*route);
 179
 180                 PrintDebug("VNET Route Added\n");
 181
 182                 if (tmp_status != 0) {
 183                     PrintError("Error adding VNET ROUTE\n");
 184                     status = tmp_status;
 185                 }
 186
 187                 xfer_len += buf_desc->length;
 188                 desc_idx = buf_desc->next;
 189             }
 190
 191         }
 192
 193
 194
 195         status_desc = &(q->desc[desc_idx]);
 196
 197         if (v3_gpa_to_hva(core, status_desc->addr_gpa, (addr_t *)&status_ptr) == -1) {
 198             PrintError("VirtioVNET Error could not translate status address\n");
 199             return -1;
 200         }
 201
 202         xfer_len += status_desc->length;
 203         *status_ptr = status;
 204
 205         PrintDebug("Transferred %d bytes (xfer_len)\n", xfer_len);
 206         q->used->ring[q->used->index % QUEUE_SIZE].id = q->avail->ring[q->cur_avail_idx % QUEUE_SIZE];
 207         q->used->ring[q->used->index % QUEUE_SIZE].length = xfer_len; // set to total inbound xfer length
 208
 209         q->used->index++;
 210         q->cur_avail_idx++;
 211     }
 212
 213
 214     if (!(q->avail->flags & VIRTIO_NO_IRQ_FLAG)) {
 215         PrintDebug("Raising IRQ %d\n",  vnet_state->pci_dev->config_header.intr_line);
 216         v3_pci_raise_irq(vnet_state->pci_bus, 0, vnet_state->pci_dev);
 217         vnet_state->virtio_cfg.pci_isr = 1;
 218     }
 219
 220
 221     return 0;
 222 }
 223
 224
 225 static int vnet_pkt_input_cb(struct v3_vm_info * vm,  struct v3_vnet_pkt *pkt, void * private_data){
 226     struct virtio_vnet_state * vnet_state = (struct virtio_vnet_state *)private_data;
 227     struct virtio_queue * q = &(vnet_state->queue[RECV_QUEUE]);
 228     int ret_val = -1;
 229     unsigned long flags;
 230     uint16_t sent;
 231
 232     flags = v3_lock_irqsave(vnet_state->lock);
 233
 234     if (q->ring_avail_addr == 0) {
 235         PrintError("Queue is not set\n");
 236         goto exit;
 237     }
 238
 239     if (q->cur_avail_idx != q->avail->index) {
 240         uint16_t pkt_idx = q->avail->ring[q->cur_avail_idx % q->queue_size];
 241         struct vring_desc * pkt_desc = NULL;
 242         struct vnet_bridge_pkt * virtio_pkt = NULL;
 243
 244         pkt_desc = &(q->desc[pkt_idx]);
 245         PrintDebug("VNET Bridge RX: buffer desc len: %d\n", pkt_desc->length);
 246
 247         if (v3_gpa_to_hva(&(vm->cores[0]), pkt_desc->addr_gpa, (addr_t *)&(virtio_pkt)) == -1) {
 248             PrintError("Could not translate buffer address\n");
 249             goto exit;
 250         }
 251
 252         PrintDebug("VNET Bridge: RX: pkt sent to guest pkt size: %d, dst link: %d\n", pkt->size, pkt->dst_id);
 253
 254         // Fill in dst packet buffer
 255         virtio_pkt->link_id = pkt->dst_id;
 256         virtio_pkt->pkt_size = pkt->size;
 257         memcpy(virtio_pkt->pkt, pkt->data, pkt->size);
 258
 259         q->used->ring[q->used->index % q->queue_size].id = q->avail->ring[q->cur_avail_idx % q->queue_size];
 260         q->used->ring[q->used->index % q->queue_size].length = sizeof(struct vnet_bridge_pkt);
 261
 262         q->used->index++;
 263         q->cur_avail_idx++;
 264     } else {
 265         vnet_state->pkt_drop ++;
 266     }
 267
 268     if (!(q->avail->flags & VIRTIO_NO_IRQ_FLAG)) {
 269         v3_pci_raise_irq(vnet_state->pci_bus, 0, vnet_state->pci_dev);
 270         vnet_state->virtio_cfg.pci_isr = 0x1;
 271         PrintDebug("Raising IRQ %d\n",  vnet_state->pci_dev->config_header.intr_line);
 272     }
 273
 274     ret_val = 0;
 275
 276 exit:
 277
 278     v3_unlock_irqrestore(vnet_state->lock, flags);
 279
 280     return ret_val;
 281 }
 282
 283 static int vnet_pkt_input_xcall(void *data){
 284     struct v3_vnet_bridge_xcall_args *args = (struct v3_vnet_bridge_xcall_args *)data;
 285     int i = 0;
 286
 287     for(i = 0; i < args->pkt_num; i++) {
 288         vnet_pkt_input_cb(args->vm, args->vnet_pkts[i], args->private_data);
 289     }
 290
 291     return 0;
 292 }
 293
 294 static int handle_pkt_kick(struct guest_info *core, struct virtio_vnet_state * vnet_state)
 295 {
 296     struct virtio_queue * q = &(vnet_state->queue[XMIT_QUEUE]);
 297     int recvd = 0;
 298
 299     if (q->ring_avail_addr == 0) {
 300         return -1;
 301     }
 302
 303     while (q->cur_avail_idx != q->avail->index) {
 304         uint16_t desc_idx = q->avail->ring[q->cur_avail_idx % q->queue_size];
 305         struct vring_desc * pkt_desc = NULL;
 306         struct vnet_bridge_pkt * virtio_pkt = NULL;
 307
 308         pkt_desc = &(q->desc[desc_idx]);
 309
 310         PrintDebug("VNET Bridge: Handle TX desc buf_len: %d\n", pkt_desc->length);
 311
 312         if (v3_gpa_to_hva(core, pkt_desc->addr_gpa, (addr_t *)&(virtio_pkt)) == -1) {
 313             PrintError("Could not translate buffer address\n");
 314             return -1;
 315         }
 316
 317         //PrintDebug("VNET Bridge: TX: on cpu %d pkt size: %d, dst link: %d\n", cpu, virtio_pkt->pkt_size, virtio_pkt->link_id);
 318
 319         struct v3_vnet_pkt pkt;
 320         pkt.size = virtio_pkt->pkt_size;
 321         pkt.src_type = LINK_EDGE;
 322         pkt.src_id = 0;
 323         memcpy(pkt.header, virtio_pkt->pkt, ETHERNET_HEADER_LEN);
 324         pkt.data = virtio_pkt->pkt;
 325
 326         v3_vnet_send_pkt(&pkt, NULL);
 327
 328         q->used->ring[q->used->index % q->queue_size].id = q->avail->ring[q->cur_avail_idx % q->queue_size];
 329         q->used->ring[q->used->index % q->queue_size].length = pkt_desc->length; // What do we set this to????
 330         q->used->index++;
 331
 332         vnet_state->pkt_sent ++;
 333         recvd ++;
 334
 335         q->cur_avail_idx++;
 336     }
 337
 338     if(recvd == 0){
 339         return 0;
 340     }
 341
 342     if (!(q->avail->flags & VIRTIO_NO_IRQ_FLAG)) {
 343             v3_pci_raise_irq(vnet_state->pci_bus, 0, vnet_state->pci_dev);
 344             vnet_state->virtio_cfg.pci_isr = 0x1;
 345     }
 346
 347     return 0;
 348 }
 349
 350 static void vnet_virtio_poll(struct v3_vm_info * vm, void *private_data){
 351     struct virtio_vnet_state * vnet_state = (struct virtio_vnet_state *)private_data;
 352
 353     if(vm == vnet_state->vm){
 354         handle_pkt_kick(&(vm->cores[0]), vnet_state);
 355     }
 356 }
 357
 358 static int handle_rx_kick(struct guest_info *core, struct virtio_vnet_state * vnet_state)
 359 {
 360     //v3_vnet_enable_bridge();
 361
 362     return 0;
 363 }
 364
 365 static int vnet_virtio_io_write(struct guest_info * core, uint16_t port, void * src, uint_t length, void * private_data) {
 366     struct virtio_vnet_state * vnet_state = (struct virtio_vnet_state *)private_data;
 367     int port_idx = port % vnet_state->io_range_size;
 368
 369     PrintDebug("VNET Bridge: VIRTIO VNET Write for port %d len=%d, value=%x\n",
 370                port, length, *(uint32_t *)src);
 371
 372     vnet_state->total_exit ++;
 373     switch (port_idx) {
 374         case GUEST_FEATURES_PORT:
 375             if (length != 4) {
 376                 PrintError("Illegal write length for guest features\n");
 377                 return -1;
 378             }
 379             vnet_state->virtio_cfg.guest_features = *(uint32_t *)src;
 380
 381             break;
 382         case VRING_PG_NUM_PORT:
 383             if (length == 4) {
 384                 addr_t pfn = *(uint32_t *)src;
 385                 addr_t page_addr = (pfn << VIRTIO_PAGE_SHIFT);
 386
 387                 vnet_state->cur_queue->pfn = pfn;
 388
 389                 vnet_state->cur_queue->ring_desc_addr = page_addr ;
 390                 vnet_state->cur_queue->ring_avail_addr = page_addr + (QUEUE_SIZE * sizeof(struct vring_desc));
 391                 vnet_state->cur_queue->ring_used_addr = ( vnet_state->cur_queue->ring_avail_addr + \
 392                                                  sizeof(struct vring_avail)    + \
 393                                                  (QUEUE_SIZE * sizeof(uint16_t)));
 394
 395                 // round up to next page boundary.
 396                 vnet_state->cur_queue->ring_used_addr = (vnet_state->cur_queue->ring_used_addr + 0xfff) & ~0xfff;
 397
 398                 if (v3_gpa_to_hva(core, vnet_state->cur_queue->ring_desc_addr, (addr_t *)&(vnet_state->cur_queue->desc)) == -1) {
 399                     PrintError("Could not translate ring descriptor address\n");
 400                     return -1;
 401                 }
 402
 403                 if (v3_gpa_to_hva(core, vnet_state->cur_queue->ring_avail_addr, (addr_t *)&(vnet_state->cur_queue->avail)) == -1) {
 404                     PrintError("Could not translate ring available address\n");
 405                     return -1;
 406                 }
 407
 408                 if (v3_gpa_to_hva(core, vnet_state->cur_queue->ring_used_addr, (addr_t *)&(vnet_state->cur_queue->used)) == -1) {
 409                     PrintError("Could not translate ring used address\n");
 410                     return -1;
 411                 }
 412
 413                 PrintDebug("VNET Bridge: RingDesc_addr=%p, Avail_addr=%p, Used_addr=%p\n",
 414                            (void *)(vnet_state->cur_queue->ring_desc_addr),
 415                            (void *)(vnet_state->cur_queue->ring_avail_addr),
 416                            (void *)(vnet_state->cur_queue->ring_used_addr));
 417
 418                 PrintDebug("VNET Bridge: RingDesc=%p, Avail=%p, Used=%p\n",
 419                            vnet_state->cur_queue->desc, vnet_state->cur_queue->avail, vnet_state->cur_queue->used);
 420
 421                 if(vnet_state->queue[RECV_QUEUE].avail != NULL){
 422                     vnet_state->ready = 1;
 423                     vnet_state->queue[RECV_QUEUE].used->flags |= VRING_NO_NOTIFY_FLAG;
 424                 }
 425
 426                 //No notify when there is pkt tx from guest
 427                 //palacios will do the polling
 428                 if(vnet_state->queue[XMIT_QUEUE].used != NULL){
 429                     vnet_state->queue[XMIT_QUEUE].used->flags |= VRING_NO_NOTIFY_FLAG;
 430                 }
 431             } else {
 432                 PrintError("Illegal write length for page frame number\n");
 433                 return -1;
 434             }
 435             break;
 436         case VRING_Q_SEL_PORT:
 437             vnet_state->virtio_cfg.vring_queue_selector = *(uint16_t *)src;
 438
 439             if (vnet_state->virtio_cfg.vring_queue_selector > NUM_QUEUES) {
 440                 PrintError("VNET Bridge device has no qeueues. Selected %d\n",
 441                            vnet_state->virtio_cfg.vring_queue_selector);
 442                 return -1;
 443             }
 444
 445             vnet_state->cur_queue = &(vnet_state->queue[vnet_state->virtio_cfg.vring_queue_selector]);
 446
 447             break;
 448         case VRING_Q_NOTIFY_PORT: {
 449             uint16_t queue_idx = *(uint16_t *)src;
 450
 451             PrintDebug("VNET Bridge: Handling Kick\n");
 452
 453             if (queue_idx == 0) {
 454                 if (handle_cmd_kick(core, vnet_state) == -1) {
 455                     PrintError("Could not handle Virtio VNET Control command\n");
 456                     return -1;
 457                 }
 458             } else if (queue_idx == 1) {
 459                 if (handle_pkt_kick(core, vnet_state) == -1){
 460                     PrintError("Could not handle Virtio VNET TX\n");
 461                     return -1;
 462                 }
 463                 PrintError("Notify on TX\n");
 464             } else if (queue_idx == 2) {
 465                 if (handle_rx_kick(core, vnet_state) == -1){
 466                     PrintError("Could not handle Virtio RX buffer refills Kick\n");
 467                     return -1;
 468                 }
 469                 vnet_state->rx_exit ++;
 470             } else {
 471                 PrintError("VNET Bridge: Kick on invalid queue (%d)\n", queue_idx);
 472                 return -1;
 473             }
 474
 475             break;
 476         }
 477         case VIRTIO_STATUS_PORT:
 478             vnet_state->virtio_cfg.status = *(uint8_t *)src;
 479
 480             if (vnet_state->virtio_cfg.status == 0) {
 481                 PrintDebug("VNET Bridge: Resetting device\n");
 482                 virtio_reset(vnet_state);
 483             }
 484
 485             break;
 486
 487         case VIRTIO_ISR_PORT:
 488             vnet_state->virtio_cfg.pci_isr = *(uint8_t *)src;
 489             break;
 490         default:
 491             return -1;
 492             break;
 493     }
 494
 495     return length;
 496 }
 497
 498
 499 static int vnet_virtio_io_read(struct guest_info * core, uint16_t port, void * dst, uint_t length, void * private_data) {
 500
 501     struct virtio_vnet_state * vnet_state = (struct virtio_vnet_state *)private_data;
 502     int port_idx = port % vnet_state->io_range_size;
 503
 504     switch (port_idx) {
 505         case HOST_FEATURES_PORT:
 506             if (length != 4) {
 507                 PrintError("Illegal read length for host features\n");
 508                 return -1;
 509             }
 510
 511             *(uint32_t *)dst = vnet_state->virtio_cfg.host_features;
 512
 513             break;
 514         case VRING_PG_NUM_PORT:
 515             if (length != 4) {
 516                 PrintError("Illegal read length for page frame number\n");
 517                 return -1;
 518             }
 519
 520             *(uint32_t *)dst = vnet_state->cur_queue->pfn;
 521
 522             break;
 523         case VRING_SIZE_PORT:
 524             if (length != 2) {
 525                 PrintError("Illegal read length for vring size\n");
 526                 return -1;
 527             }
 528
 529             *(uint16_t *)dst = vnet_state->cur_queue->queue_size;
 530
 531             break;
 532
 533         case VIRTIO_STATUS_PORT:
 534             if (length != 1) {
 535                 PrintError("Illegal read length for status\n");
 536                 return -1;
 537             }
 538
 539             *(uint8_t *)dst = vnet_state->virtio_cfg.status;
 540             break;
 541
 542         case VIRTIO_ISR_PORT:
 543             *(uint8_t *)dst = vnet_state->virtio_cfg.pci_isr;
 544             vnet_state->virtio_cfg.pci_isr = 0;
 545             v3_pci_lower_irq(vnet_state->pci_bus, 0, vnet_state->pci_dev);
 546             break;
 547
 548         default:
 549             if ( (port_idx >= sizeof(struct virtio_config)) &&
 550                  (port_idx < (sizeof(struct virtio_config) + sizeof(struct vnet_config))) ) {
 551                 int cfg_offset = port_idx - sizeof(struct virtio_config);
 552                 uint8_t * cfg_ptr = (uint8_t *)&(vnet_state->vnet_cfg);
 553
 554                 memcpy(dst, cfg_ptr + cfg_offset, length);
 555
 556             } else {
 557                 PrintError("Read of Unhandled Virtio Read\n");
 558                 return -1;
 559             }
 560
 561             break;
 562     }
 563
 564     return length;
 565 }
 566
 567
 568
 569 static struct v3_device_ops dev_ops = {
 570     .free = NULL,
 571     .reset = NULL,
 572     .start = NULL,
 573     .stop = NULL,
 574 };
 575
 576 static int dev_init(struct v3_vm_info * vm, v3_cfg_tree_t * cfg) {
 577     struct vm_device * pci_bus = v3_find_dev(vm, v3_cfg_val(cfg, "bus"));
 578     struct virtio_vnet_state * vnet_state = NULL;
 579     struct pci_device * pci_dev = NULL;
 580     char * name = v3_cfg_val(cfg, "name");
 581
 582     PrintDebug("VNET Bridge: Initializing VNET Bridge Control device: %s\n", name);
 583
 584     if (pci_bus == NULL) {
 585         PrintError("VNET Bridge device require a PCI Bus");
 586         return -1;
 587     }
 588
 589     vnet_state  = (struct virtio_vnet_state *)V3_Malloc(sizeof(struct virtio_vnet_state));
 590     memset(vnet_state, 0, sizeof(struct virtio_vnet_state));
 591
 592     vnet_state->vm = vm;
 593
 594     struct vm_device * dev = v3_allocate_device(name, &dev_ops, vnet_state);
 595
 596     if (v3_attach_device(vm, dev) == -1) {
 597         PrintError("Could not attach device %s\n", name);
 598         return -1;
 599     }
 600
 601
 602     // PCI initialization
 603     {
 604         struct v3_pci_bar bars[6];
 605         int num_ports = sizeof(struct virtio_config) + sizeof(struct vnet_config);
 606         int tmp_ports = num_ports;
 607         int i;
 608
 609         // This gets the number of ports, rounded up to a power of 2
 610         vnet_state->io_range_size = 1; // must be a power of 2
 611
 612         while (tmp_ports > 0) {
 613             tmp_ports >>= 1;
 614             vnet_state->io_range_size <<= 1;
 615         }
 616
 617         // this is to account for any low order bits being set in num_ports
 618         // if there are none, then num_ports was already a power of 2 so we shift right to reset it
 619         if ((num_ports & ((vnet_state->io_range_size >> 1) - 1)) == 0) {
 620             vnet_state->io_range_size >>= 1;
 621         }
 622
 623         for (i = 0; i < 6; i++) {
 624             bars[i].type = PCI_BAR_NONE;
 625         }
 626
 627         bars[0].type = PCI_BAR_IO;
 628         bars[0].default_base_port = -1;
 629         bars[0].num_ports = vnet_state->io_range_size;
 630         bars[0].io_read = vnet_virtio_io_read;
 631         bars[0].io_write = vnet_virtio_io_write;
 632         bars[0].private_data = vnet_state;
 633
 634         pci_dev = v3_pci_register_device(pci_bus, PCI_STD_DEVICE,
 635                                          0, 5 /*PCI_AUTO_DEV_NUM*/, 0,
 636                                          "LNX_VIRTIO_VNET", bars,
 637                                          NULL, NULL, NULL, vnet_state);
 638
 639         if (!pci_dev) {
 640             PrintError("Could not register PCI Device\n");
 641             return -1;
 642         }
 643
 644         pci_dev->config_header.vendor_id = VIRTIO_VENDOR_ID;
 645         pci_dev->config_header.subsystem_vendor_id = VIRTIO_SUBVENDOR_ID;
 646         pci_dev->config_header.device_id = VIRTIO_VNET_DEV_ID;
 647         pci_dev->config_header.class = PCI_CLASS_MEMORY;
 648         pci_dev->config_header.subclass = PCI_MEM_SUBCLASS_RAM;
 649         pci_dev->config_header.subsystem_id = VIRTIO_VNET_SUBDEVICE_ID;
 650         pci_dev->config_header.intr_pin = 1;
 651         pci_dev->config_header.max_latency = 1; // ?? (qemu does it...)
 652
 653
 654         vnet_state->pci_dev = pci_dev;
 655         vnet_state->pci_bus = pci_bus;
 656     }
 657
 658     virtio_reset(vnet_state);
 659
 660     struct v3_vnet_bridge_ops brg_ops;
 661     brg_ops.input = vnet_pkt_input_cb;
 662     brg_ops.polling_pkt = vnet_virtio_poll;
 663     brg_ops.xcall_input = vnet_pkt_input_xcall;
 664
 665     V3_Print("Registering Virtio device as vnet bridge\n");
 666     v3_vnet_add_bridge(vm, &brg_ops, (void *)vnet_state);
 667
 668     return 0;
 669 }
 670
 671
 672 device_register("LNX_VIRTIO_VNET", dev_init)