1 /* A simple network driver using virtio. 2 * 3 * Copyright 2007 Rusty Russell <rusty@rustcorp.com.au> IBM Corporation 4 * 5 * This program is free software; you can redistribute it and/or modify 6 * it under the terms of the GNU General Public License as published by 7 * the Free Software Foundation; either version 2 of the License, or 8 * (at your option) any later version. 9 * 10 * This program is distributed in the hope that it will be useful, 11 * but WITHOUT ANY WARRANTY; without even the implied warranty of 12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 13 * GNU General Public License for more details. 14 * 15 * You should have received a copy of the GNU General Public License 16 * along with this program; if not, write to the Free Software 17 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 18 */ 19 //#define DEBUG 20 #include <linux/netdevice.h> 21 #include <linux/etherdevice.h> 22 #include <linux/ethtool.h> 23 #include <linux/module.h> 24 #include <linux/virtio.h> 25 #include <linux/virtio_net.h> 26 #include <linux/scatterlist.h> 27 #include <linux/if_vlan.h> 28 29 static int napi_weight = 128; 30 module_param(napi_weight, int, 0444); 31 32 static int csum = 1, gso = 1; 33 module_param(csum, bool, 0444); 34 module_param(gso, bool, 0444); 35 36 /* FIXME: MTU in config. */ 37 #define MAX_PACKET_LEN (ETH_HLEN + VLAN_HLEN + ETH_DATA_LEN) 38 #define GOOD_COPY_LEN 128 39 40 #define VIRTNET_SEND_COMMAND_SG_MAX 2 41 42 struct virtnet_info 43 { 44 struct virtio_device *vdev; 45 struct virtqueue *rvq, *svq, *cvq; 46 struct net_device *dev; 47 struct napi_struct napi; 48 unsigned int status; 49 50 /* The skb we couldn't send because buffers were full. */ 51 struct sk_buff *last_xmit_skb; 52 53 /* If we need to free in a timer, this is it. */ 54 struct timer_list xmit_free_timer; 55 56 /* Number of input buffers, and max we've ever had. */ 57 unsigned int num, max; 58 59 /* For cleaning up after transmission. */ 60 struct tasklet_struct tasklet; 61 bool free_in_tasklet; 62 63 /* I like... big packets and I cannot lie! */ 64 bool big_packets; 65 66 /* Host will merge rx buffers for big packets (shake it! shake it!) */ 67 bool mergeable_rx_bufs; 68 69 /* Receive & send queues. */ 70 struct sk_buff_head recv; 71 struct sk_buff_head send; 72 73 /* Chain pages by the private ptr. */ 74 struct page *pages; 75 }; 76 77 static inline void *skb_vnet_hdr(struct sk_buff *skb) 78 { 79 return (struct virtio_net_hdr *)skb->cb; 80 } 81 82 static void give_a_page(struct virtnet_info *vi, struct page *page) 83 { 84 page->private = (unsigned long)vi->pages; 85 vi->pages = page; 86 } 87 88 static void trim_pages(struct virtnet_info *vi, struct sk_buff *skb) 89 { 90 unsigned int i; 91 92 for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) 93 give_a_page(vi, skb_shinfo(skb)->frags[i].page); 94 skb_shinfo(skb)->nr_frags = 0; 95 skb->data_len = 0; 96 } 97 98 static struct page *get_a_page(struct virtnet_info *vi, gfp_t gfp_mask) 99 { 100 struct page *p = vi->pages; 101 102 if (p) 103 vi->pages = (struct page *)p->private; 104 else 105 p = alloc_page(gfp_mask); 106 return p; 107 } 108 109 static void skb_xmit_done(struct virtqueue *svq) 110 { 111 struct virtnet_info *vi = svq->vdev->priv; 112 113 /* Suppress further interrupts. */ 114 svq->vq_ops->disable_cb(svq); 115 116 /* We were probably waiting for more output buffers. */ 117 netif_wake_queue(vi->dev); 118 119 /* Make sure we re-xmit last_xmit_skb: if there are no more packets 120 * queued, start_xmit won't be called. */ 121 tasklet_schedule(&vi->tasklet); 122 } 123 124 static void receive_skb(struct net_device *dev, struct sk_buff *skb, 125 unsigned len) 126 { 127 struct virtnet_info *vi = netdev_priv(dev); 128 struct virtio_net_hdr *hdr = skb_vnet_hdr(skb); 129 int err; 130 int i; 131 132 if (unlikely(len < sizeof(struct virtio_net_hdr) + ETH_HLEN)) { 133 pr_debug("%s: short packet %i\n", dev->name, len); 134 dev->stats.rx_length_errors++; 135 goto drop; 136 } 137 138 if (vi->mergeable_rx_bufs) { 139 struct virtio_net_hdr_mrg_rxbuf *mhdr = skb_vnet_hdr(skb); 140 unsigned int copy; 141 char *p = page_address(skb_shinfo(skb)->frags[0].page); 142 143 if (len > PAGE_SIZE) 144 len = PAGE_SIZE; 145 len -= sizeof(struct virtio_net_hdr_mrg_rxbuf); 146 147 memcpy(hdr, p, sizeof(*mhdr)); 148 p += sizeof(*mhdr); 149 150 copy = len; 151 if (copy > skb_tailroom(skb)) 152 copy = skb_tailroom(skb); 153 154 memcpy(skb_put(skb, copy), p, copy); 155 156 len -= copy; 157 158 if (!len) { 159 give_a_page(vi, skb_shinfo(skb)->frags[0].page); 160 skb_shinfo(skb)->nr_frags--; 161 } else { 162 skb_shinfo(skb)->frags[0].page_offset += 163 sizeof(*mhdr) + copy; 164 skb_shinfo(skb)->frags[0].size = len; 165 skb->data_len += len; 166 skb->len += len; 167 } 168 169 while (--mhdr->num_buffers) { 170 struct sk_buff *nskb; 171 172 i = skb_shinfo(skb)->nr_frags; 173 if (i >= MAX_SKB_FRAGS) { 174 pr_debug("%s: packet too long %d\n", dev->name, 175 len); 176 dev->stats.rx_length_errors++; 177 goto drop; 178 } 179 180 nskb = vi->rvq->vq_ops->get_buf(vi->rvq, &len); 181 if (!nskb) { 182 pr_debug("%s: rx error: %d buffers missing\n", 183 dev->name, mhdr->num_buffers); 184 dev->stats.rx_length_errors++; 185 goto drop; 186 } 187 188 __skb_unlink(nskb, &vi->recv); 189 vi->num--; 190 191 skb_shinfo(skb)->frags[i] = skb_shinfo(nskb)->frags[0]; 192 skb_shinfo(nskb)->nr_frags = 0; 193 kfree_skb(nskb); 194 195 if (len > PAGE_SIZE) 196 len = PAGE_SIZE; 197 198 skb_shinfo(skb)->frags[i].size = len; 199 skb_shinfo(skb)->nr_frags++; 200 skb->data_len += len; 201 skb->len += len; 202 } 203 } else { 204 len -= sizeof(struct virtio_net_hdr); 205 206 if (len <= MAX_PACKET_LEN) 207 trim_pages(vi, skb); 208 209 err = pskb_trim(skb, len); 210 if (err) { 211 pr_debug("%s: pskb_trim failed %i %d\n", dev->name, 212 len, err); 213 dev->stats.rx_dropped++; 214 goto drop; 215 } 216 } 217 218 skb->truesize += skb->data_len; 219 dev->stats.rx_bytes += skb->len; 220 dev->stats.rx_packets++; 221 222 if (hdr->flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) { 223 pr_debug("Needs csum!\n"); 224 if (!skb_partial_csum_set(skb,hdr->csum_start,hdr->csum_offset)) 225 goto frame_err; 226 } 227 228 skb->protocol = eth_type_trans(skb, dev); 229 pr_debug("Receiving skb proto 0x%04x len %i type %i\n", 230 ntohs(skb->protocol), skb->len, skb->pkt_type); 231 232 if (hdr->gso_type != VIRTIO_NET_HDR_GSO_NONE) { 233 pr_debug("GSO!\n"); 234 switch (hdr->gso_type & ~VIRTIO_NET_HDR_GSO_ECN) { 235 case VIRTIO_NET_HDR_GSO_TCPV4: 236 skb_shinfo(skb)->gso_type = SKB_GSO_TCPV4; 237 break; 238 case VIRTIO_NET_HDR_GSO_UDP: 239 skb_shinfo(skb)->gso_type = SKB_GSO_UDP; 240 break; 241 case VIRTIO_NET_HDR_GSO_TCPV6: 242 skb_shinfo(skb)->gso_type = SKB_GSO_TCPV6; 243 break; 244 default: 245 if (net_ratelimit()) 246 printk(KERN_WARNING "%s: bad gso type %u.\n", 247 dev->name, hdr->gso_type); 248 goto frame_err; 249 } 250 251 if (hdr->gso_type & VIRTIO_NET_HDR_GSO_ECN) 252 skb_shinfo(skb)->gso_type |= SKB_GSO_TCP_ECN; 253 254 skb_shinfo(skb)->gso_size = hdr->gso_size; 255 if (skb_shinfo(skb)->gso_size == 0) { 256 if (net_ratelimit()) 257 printk(KERN_WARNING "%s: zero gso size.\n", 258 dev->name); 259 goto frame_err; 260 } 261 262 /* Header must be checked, and gso_segs computed. */ 263 skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY; 264 skb_shinfo(skb)->gso_segs = 0; 265 } 266 267 netif_receive_skb(skb); 268 return; 269 270 frame_err: 271 dev->stats.rx_frame_errors++; 272 drop: 273 dev_kfree_skb(skb); 274 } 275 276 static void try_fill_recv_maxbufs(struct virtnet_info *vi) 277 { 278 struct sk_buff *skb; 279 struct scatterlist sg[2+MAX_SKB_FRAGS]; 280 int num, err, i; 281 282 sg_init_table(sg, 2+MAX_SKB_FRAGS); 283 for (;;) { 284 struct virtio_net_hdr *hdr; 285 286 skb = netdev_alloc_skb(vi->dev, MAX_PACKET_LEN + NET_IP_ALIGN); 287 if (unlikely(!skb)) 288 break; 289 290 skb_reserve(skb, NET_IP_ALIGN); 291 skb_put(skb, MAX_PACKET_LEN); 292 293 hdr = skb_vnet_hdr(skb); 294 sg_set_buf(sg, hdr, sizeof(*hdr)); 295 296 if (vi->big_packets) { 297 for (i = 0; i < MAX_SKB_FRAGS; i++) { 298 skb_frag_t *f = &skb_shinfo(skb)->frags[i]; 299 f->page = get_a_page(vi, GFP_ATOMIC); 300 if (!f->page) 301 break; 302 303 f->page_offset = 0; 304 f->size = PAGE_SIZE; 305 306 skb->data_len += PAGE_SIZE; 307 skb->len += PAGE_SIZE; 308 309 skb_shinfo(skb)->nr_frags++; 310 } 311 } 312 313 num = skb_to_sgvec(skb, sg+1, 0, skb->len) + 1; 314 skb_queue_head(&vi->recv, skb); 315 316 err = vi->rvq->vq_ops->add_buf(vi->rvq, sg, 0, num, skb); 317 if (err) { 318 skb_unlink(skb, &vi->recv); 319 trim_pages(vi, skb); 320 kfree_skb(skb); 321 break; 322 } 323 vi->num++; 324 } 325 if (unlikely(vi->num > vi->max)) 326 vi->max = vi->num; 327 vi->rvq->vq_ops->kick(vi->rvq); 328 } 329 330 static void try_fill_recv(struct virtnet_info *vi) 331 { 332 struct sk_buff *skb; 333 struct scatterlist sg[1]; 334 int err; 335 336 if (!vi->mergeable_rx_bufs) { 337 try_fill_recv_maxbufs(vi); 338 return; 339 } 340 341 for (;;) { 342 skb_frag_t *f; 343 344 skb = netdev_alloc_skb(vi->dev, GOOD_COPY_LEN + NET_IP_ALIGN); 345 if (unlikely(!skb)) 346 break; 347 348 skb_reserve(skb, NET_IP_ALIGN); 349 350 f = &skb_shinfo(skb)->frags[0]; 351 f->page = get_a_page(vi, GFP_ATOMIC); 352 if (!f->page) { 353 kfree_skb(skb); 354 break; 355 } 356 357 f->page_offset = 0; 358 f->size = PAGE_SIZE; 359 360 skb_shinfo(skb)->nr_frags++; 361 362 sg_init_one(sg, page_address(f->page), PAGE_SIZE); 363 skb_queue_head(&vi->recv, skb); 364 365 err = vi->rvq->vq_ops->add_buf(vi->rvq, sg, 0, 1, skb); 366 if (err) { 367 skb_unlink(skb, &vi->recv); 368 kfree_skb(skb); 369 break; 370 } 371 vi->num++; 372 } 373 if (unlikely(vi->num > vi->max)) 374 vi->max = vi->num; 375 vi->rvq->vq_ops->kick(vi->rvq); 376 } 377 378 static void skb_recv_done(struct virtqueue *rvq) 379 { 380 struct virtnet_info *vi = rvq->vdev->priv; 381 /* Schedule NAPI, Suppress further interrupts if successful. */ 382 if (napi_schedule_prep(&vi->napi)) { 383 rvq->vq_ops->disable_cb(rvq); 384 __napi_schedule(&vi->napi); 385 } 386 } 387 388 static int virtnet_poll(struct napi_struct *napi, int budget) 389 { 390 struct virtnet_info *vi = container_of(napi, struct virtnet_info, napi); 391 struct sk_buff *skb = NULL; 392 unsigned int len, received = 0; 393 394 again: 395 while (received < budget && 396 (skb = vi->rvq->vq_ops->get_buf(vi->rvq, &len)) != NULL) { 397 __skb_unlink(skb, &vi->recv); 398 receive_skb(vi->dev, skb, len); 399 vi->num--; 400 received++; 401 } 402 403 /* FIXME: If we oom and completely run out of inbufs, we need 404 * to start a timer trying to fill more. */ 405 if (vi->num < vi->max / 2) 406 try_fill_recv(vi); 407 408 /* Out of packets? */ 409 if (received < budget) { 410 napi_complete(napi); 411 if (unlikely(!vi->rvq->vq_ops->enable_cb(vi->rvq)) 412 && napi_schedule_prep(napi)) { 413 vi->rvq->vq_ops->disable_cb(vi->rvq); 414 __napi_schedule(napi); 415 goto again; 416 } 417 } 418 419 return received; 420 } 421 422 static void free_old_xmit_skbs(struct virtnet_info *vi) 423 { 424 struct sk_buff *skb; 425 unsigned int len; 426 427 while ((skb = vi->svq->vq_ops->get_buf(vi->svq, &len)) != NULL) { 428 pr_debug("Sent skb %p\n", skb); 429 __skb_unlink(skb, &vi->send); 430 vi->dev->stats.tx_bytes += skb->len; 431 vi->dev->stats.tx_packets++; 432 kfree_skb(skb); 433 } 434 } 435 436 /* If the virtio transport doesn't always notify us when all in-flight packets 437 * are consumed, we fall back to using this function on a timer to free them. */ 438 static void xmit_free(unsigned long data) 439 { 440 struct virtnet_info *vi = (void *)data; 441 442 netif_tx_lock(vi->dev); 443 444 free_old_xmit_skbs(vi); 445 446 if (!skb_queue_empty(&vi->send)) 447 mod_timer(&vi->xmit_free_timer, jiffies + (HZ/10)); 448 449 netif_tx_unlock(vi->dev); 450 } 451 452 static int xmit_skb(struct virtnet_info *vi, struct sk_buff *skb) 453 { 454 int num, err; 455 struct scatterlist sg[2+MAX_SKB_FRAGS]; 456 struct virtio_net_hdr_mrg_rxbuf *mhdr = skb_vnet_hdr(skb); 457 struct virtio_net_hdr *hdr = skb_vnet_hdr(skb); 458 const unsigned char *dest = ((struct ethhdr *)skb->data)->h_dest; 459 460 sg_init_table(sg, 2+MAX_SKB_FRAGS); 461 462 pr_debug("%s: xmit %p %pM\n", vi->dev->name, skb, dest); 463 464 if (skb->ip_summed == CHECKSUM_PARTIAL) { 465 hdr->flags = VIRTIO_NET_HDR_F_NEEDS_CSUM; 466 hdr->csum_start = skb->csum_start - skb_headroom(skb); 467 hdr->csum_offset = skb->csum_offset; 468 } else { 469 hdr->flags = 0; 470 hdr->csum_offset = hdr->csum_start = 0; 471 } 472 473 if (skb_is_gso(skb)) { 474 hdr->hdr_len = skb_headlen(skb); 475 hdr->gso_size = skb_shinfo(skb)->gso_size; 476 if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV4) 477 hdr->gso_type = VIRTIO_NET_HDR_GSO_TCPV4; 478 else if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV6) 479 hdr->gso_type = VIRTIO_NET_HDR_GSO_TCPV6; 480 else if (skb_shinfo(skb)->gso_type & SKB_GSO_UDP) 481 hdr->gso_type = VIRTIO_NET_HDR_GSO_UDP; 482 else 483 BUG(); 484 if (skb_shinfo(skb)->gso_type & SKB_GSO_TCP_ECN) 485 hdr->gso_type |= VIRTIO_NET_HDR_GSO_ECN; 486 } else { 487 hdr->gso_type = VIRTIO_NET_HDR_GSO_NONE; 488 hdr->gso_size = hdr->hdr_len = 0; 489 } 490 491 mhdr->num_buffers = 0; 492 493 /* Encode metadata header at front. */ 494 if (vi->mergeable_rx_bufs) 495 sg_set_buf(sg, mhdr, sizeof(*mhdr)); 496 else 497 sg_set_buf(sg, hdr, sizeof(*hdr)); 498 499 num = skb_to_sgvec(skb, sg+1, 0, skb->len) + 1; 500 501 err = vi->svq->vq_ops->add_buf(vi->svq, sg, num, 0, skb); 502 if (!err && !vi->free_in_tasklet) 503 mod_timer(&vi->xmit_free_timer, jiffies + (HZ/10)); 504 505 return err; 506 } 507 508 static void xmit_tasklet(unsigned long data) 509 { 510 struct virtnet_info *vi = (void *)data; 511 512 netif_tx_lock_bh(vi->dev); 513 if (vi->last_xmit_skb && xmit_skb(vi, vi->last_xmit_skb) == 0) { 514 vi->svq->vq_ops->kick(vi->svq); 515 vi->last_xmit_skb = NULL; 516 } 517 if (vi->free_in_tasklet) 518 free_old_xmit_skbs(vi); 519 netif_tx_unlock_bh(vi->dev); 520 } 521 522 static int start_xmit(struct sk_buff *skb, struct net_device *dev) 523 { 524 struct virtnet_info *vi = netdev_priv(dev); 525 526 again: 527 /* Free up any pending old buffers before queueing new ones. */ 528 free_old_xmit_skbs(vi); 529 530 /* If we has a buffer left over from last time, send it now. */ 531 if (unlikely(vi->last_xmit_skb) && 532 xmit_skb(vi, vi->last_xmit_skb) != 0) 533 goto stop_queue; 534 535 vi->last_xmit_skb = NULL; 536 537 /* Put new one in send queue and do transmit */ 538 if (likely(skb)) { 539 __skb_queue_head(&vi->send, skb); 540 if (xmit_skb(vi, skb) != 0) { 541 vi->last_xmit_skb = skb; 542 skb = NULL; 543 goto stop_queue; 544 } 545 } 546 done: 547 vi->svq->vq_ops->kick(vi->svq); 548 return NETDEV_TX_OK; 549 550 stop_queue: 551 pr_debug("%s: virtio not prepared to send\n", dev->name); 552 netif_stop_queue(dev); 553 554 /* Activate callback for using skbs: if this returns false it 555 * means some were used in the meantime. */ 556 if (unlikely(!vi->svq->vq_ops->enable_cb(vi->svq))) { 557 vi->svq->vq_ops->disable_cb(vi->svq); 558 netif_start_queue(dev); 559 goto again; 560 } 561 if (skb) { 562 /* Drop this skb: we only queue one. */ 563 vi->dev->stats.tx_dropped++; 564 kfree_skb(skb); 565 } 566 goto done; 567 } 568 569 static int virtnet_set_mac_address(struct net_device *dev, void *p) 570 { 571 struct virtnet_info *vi = netdev_priv(dev); 572 struct virtio_device *vdev = vi->vdev; 573 int ret; 574 575 ret = eth_mac_addr(dev, p); 576 if (ret) 577 return ret; 578 579 if (virtio_has_feature(vdev, VIRTIO_NET_F_MAC)) 580 vdev->config->set(vdev, offsetof(struct virtio_net_config, mac), 581 dev->dev_addr, dev->addr_len); 582 583 return 0; 584 } 585 586 #ifdef CONFIG_NET_POLL_CONTROLLER 587 static void virtnet_netpoll(struct net_device *dev) 588 { 589 struct virtnet_info *vi = netdev_priv(dev); 590 591 napi_schedule(&vi->napi); 592 } 593 #endif 594 595 static int virtnet_open(struct net_device *dev) 596 { 597 struct virtnet_info *vi = netdev_priv(dev); 598 599 napi_enable(&vi->napi); 600 601 /* If all buffers were filled by other side before we napi_enabled, we 602 * won't get another interrupt, so process any outstanding packets 603 * now. virtnet_poll wants re-enable the queue, so we disable here. 604 * We synchronize against interrupts via NAPI_STATE_SCHED */ 605 if (napi_schedule_prep(&vi->napi)) { 606 vi->rvq->vq_ops->disable_cb(vi->rvq); 607 __napi_schedule(&vi->napi); 608 } 609 return 0; 610 } 611 612 /* 613 * Send command via the control virtqueue and check status. Commands 614 * supported by the hypervisor, as indicated by feature bits, should 615 * never fail unless improperly formated. 616 */ 617 static bool virtnet_send_command(struct virtnet_info *vi, u8 class, u8 cmd, 618 struct scatterlist *data, int out, int in) 619 { 620 struct scatterlist *s, sg[VIRTNET_SEND_COMMAND_SG_MAX + 2]; 621 struct virtio_net_ctrl_hdr ctrl; 622 virtio_net_ctrl_ack status = ~0; 623 unsigned int tmp; 624 int i; 625 626 /* Caller should know better */ 627 BUG_ON(!virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ) || 628 (out + in > VIRTNET_SEND_COMMAND_SG_MAX)); 629 630 out++; /* Add header */ 631 in++; /* Add return status */ 632 633 ctrl.class = class; 634 ctrl.cmd = cmd; 635 636 sg_init_table(sg, out + in); 637 638 sg_set_buf(&sg[0], &ctrl, sizeof(ctrl)); 639 for_each_sg(data, s, out + in - 2, i) 640 sg_set_buf(&sg[i + 1], sg_virt(s), s->length); 641 sg_set_buf(&sg[out + in - 1], &status, sizeof(status)); 642 643 BUG_ON(vi->cvq->vq_ops->add_buf(vi->cvq, sg, out, in, vi)); 644 645 vi->cvq->vq_ops->kick(vi->cvq); 646 647 /* 648 * Spin for a response, the kick causes an ioport write, trapping 649 * into the hypervisor, so the request should be handled immediately. 650 */ 651 while (!vi->cvq->vq_ops->get_buf(vi->cvq, &tmp)) 652 cpu_relax(); 653 654 return status == VIRTIO_NET_OK; 655 } 656 657 static int virtnet_close(struct net_device *dev) 658 { 659 struct virtnet_info *vi = netdev_priv(dev); 660 661 napi_disable(&vi->napi); 662 663 return 0; 664 } 665 666 static int virtnet_set_tx_csum(struct net_device *dev, u32 data) 667 { 668 struct virtnet_info *vi = netdev_priv(dev); 669 struct virtio_device *vdev = vi->vdev; 670 671 if (data && !virtio_has_feature(vdev, VIRTIO_NET_F_CSUM)) 672 return -ENOSYS; 673 674 return ethtool_op_set_tx_hw_csum(dev, data); 675 } 676 677 static void virtnet_set_rx_mode(struct net_device *dev) 678 { 679 struct virtnet_info *vi = netdev_priv(dev); 680 struct scatterlist sg[2]; 681 u8 promisc, allmulti; 682 struct virtio_net_ctrl_mac *mac_data; 683 struct dev_addr_list *addr; 684 struct netdev_hw_addr *ha; 685 void *buf; 686 int i; 687 688 /* We can't dynamicaly set ndo_set_rx_mode, so return gracefully */ 689 if (!virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_RX)) 690 return; 691 692 promisc = ((dev->flags & IFF_PROMISC) != 0); 693 allmulti = ((dev->flags & IFF_ALLMULTI) != 0); 694 695 sg_init_one(sg, &promisc, sizeof(promisc)); 696 697 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_RX, 698 VIRTIO_NET_CTRL_RX_PROMISC, 699 sg, 1, 0)) 700 dev_warn(&dev->dev, "Failed to %sable promisc mode.\n", 701 promisc ? "en" : "dis"); 702 703 sg_init_one(sg, &allmulti, sizeof(allmulti)); 704 705 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_RX, 706 VIRTIO_NET_CTRL_RX_ALLMULTI, 707 sg, 1, 0)) 708 dev_warn(&dev->dev, "Failed to %sable allmulti mode.\n", 709 allmulti ? "en" : "dis"); 710 711 /* MAC filter - use one buffer for both lists */ 712 mac_data = buf = kzalloc(((dev->uc.count + dev->mc_count) * ETH_ALEN) + 713 (2 * sizeof(mac_data->entries)), GFP_ATOMIC); 714 if (!buf) { 715 dev_warn(&dev->dev, "No memory for MAC address buffer\n"); 716 return; 717 } 718 719 sg_init_table(sg, 2); 720 721 /* Store the unicast list and count in the front of the buffer */ 722 mac_data->entries = dev->uc.count; 723 i = 0; 724 list_for_each_entry(ha, &dev->uc.list, list) 725 memcpy(&mac_data->macs[i++][0], ha->addr, ETH_ALEN); 726 727 sg_set_buf(&sg[0], mac_data, 728 sizeof(mac_data->entries) + (dev->uc.count * ETH_ALEN)); 729 730 /* multicast list and count fill the end */ 731 mac_data = (void *)&mac_data->macs[dev->uc.count][0]; 732 733 mac_data->entries = dev->mc_count; 734 addr = dev->mc_list; 735 for (i = 0; i < dev->mc_count; i++, addr = addr->next) 736 memcpy(&mac_data->macs[i][0], addr->da_addr, ETH_ALEN); 737 738 sg_set_buf(&sg[1], mac_data, 739 sizeof(mac_data->entries) + (dev->mc_count * ETH_ALEN)); 740 741 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_MAC, 742 VIRTIO_NET_CTRL_MAC_TABLE_SET, 743 sg, 2, 0)) 744 dev_warn(&dev->dev, "Failed to set MAC fitler table.\n"); 745 746 kfree(buf); 747 } 748 749 static void virtnet_vlan_rx_add_vid(struct net_device *dev, u16 vid) 750 { 751 struct virtnet_info *vi = netdev_priv(dev); 752 struct scatterlist sg; 753 754 sg_init_one(&sg, &vid, sizeof(vid)); 755 756 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_VLAN, 757 VIRTIO_NET_CTRL_VLAN_ADD, &sg, 1, 0)) 758 dev_warn(&dev->dev, "Failed to add VLAN ID %d.\n", vid); 759 } 760 761 static void virtnet_vlan_rx_kill_vid(struct net_device *dev, u16 vid) 762 { 763 struct virtnet_info *vi = netdev_priv(dev); 764 struct scatterlist sg; 765 766 sg_init_one(&sg, &vid, sizeof(vid)); 767 768 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_VLAN, 769 VIRTIO_NET_CTRL_VLAN_DEL, &sg, 1, 0)) 770 dev_warn(&dev->dev, "Failed to kill VLAN ID %d.\n", vid); 771 } 772 773 static struct ethtool_ops virtnet_ethtool_ops = { 774 .set_tx_csum = virtnet_set_tx_csum, 775 .set_sg = ethtool_op_set_sg, 776 .set_tso = ethtool_op_set_tso, 777 .get_link = ethtool_op_get_link, 778 }; 779 780 #define MIN_MTU 68 781 #define MAX_MTU 65535 782 783 static int virtnet_change_mtu(struct net_device *dev, int new_mtu) 784 { 785 if (new_mtu < MIN_MTU || new_mtu > MAX_MTU) 786 return -EINVAL; 787 dev->mtu = new_mtu; 788 return 0; 789 } 790 791 static const struct net_device_ops virtnet_netdev = { 792 .ndo_open = virtnet_open, 793 .ndo_stop = virtnet_close, 794 .ndo_start_xmit = start_xmit, 795 .ndo_validate_addr = eth_validate_addr, 796 .ndo_set_mac_address = virtnet_set_mac_address, 797 .ndo_set_rx_mode = virtnet_set_rx_mode, 798 .ndo_change_mtu = virtnet_change_mtu, 799 .ndo_vlan_rx_add_vid = virtnet_vlan_rx_add_vid, 800 .ndo_vlan_rx_kill_vid = virtnet_vlan_rx_kill_vid, 801 #ifdef CONFIG_NET_POLL_CONTROLLER 802 .ndo_poll_controller = virtnet_netpoll, 803 #endif 804 }; 805 806 static void virtnet_update_status(struct virtnet_info *vi) 807 { 808 u16 v; 809 810 if (!virtio_has_feature(vi->vdev, VIRTIO_NET_F_STATUS)) 811 return; 812 813 vi->vdev->config->get(vi->vdev, 814 offsetof(struct virtio_net_config, status), 815 &v, sizeof(v)); 816 817 /* Ignore unknown (future) status bits */ 818 v &= VIRTIO_NET_S_LINK_UP; 819 820 if (vi->status == v) 821 return; 822 823 vi->status = v; 824 825 if (vi->status & VIRTIO_NET_S_LINK_UP) { 826 netif_carrier_on(vi->dev); 827 netif_wake_queue(vi->dev); 828 } else { 829 netif_carrier_off(vi->dev); 830 netif_stop_queue(vi->dev); 831 } 832 } 833 834 static void virtnet_config_changed(struct virtio_device *vdev) 835 { 836 struct virtnet_info *vi = vdev->priv; 837 838 virtnet_update_status(vi); 839 } 840 841 static int virtnet_probe(struct virtio_device *vdev) 842 { 843 int err; 844 struct net_device *dev; 845 struct virtnet_info *vi; 846 struct virtqueue *vqs[3]; 847 vq_callback_t *callbacks[] = { skb_recv_done, skb_xmit_done, NULL}; 848 const char *names[] = { "input", "output", "control" }; 849 int nvqs; 850 851 /* Allocate ourselves a network device with room for our info */ 852 dev = alloc_etherdev(sizeof(struct virtnet_info)); 853 if (!dev) 854 return -ENOMEM; 855 856 /* Set up network device as normal. */ 857 dev->netdev_ops = &virtnet_netdev; 858 dev->features = NETIF_F_HIGHDMA; 859 SET_ETHTOOL_OPS(dev, &virtnet_ethtool_ops); 860 SET_NETDEV_DEV(dev, &vdev->dev); 861 862 /* Do we support "hardware" checksums? */ 863 if (csum && virtio_has_feature(vdev, VIRTIO_NET_F_CSUM)) { 864 /* This opens up the world of extra features. */ 865 dev->features |= NETIF_F_HW_CSUM|NETIF_F_SG|NETIF_F_FRAGLIST; 866 if (gso && virtio_has_feature(vdev, VIRTIO_NET_F_GSO)) { 867 dev->features |= NETIF_F_TSO | NETIF_F_UFO 868 | NETIF_F_TSO_ECN | NETIF_F_TSO6; 869 } 870 /* Individual feature bits: what can host handle? */ 871 if (gso && virtio_has_feature(vdev, VIRTIO_NET_F_HOST_TSO4)) 872 dev->features |= NETIF_F_TSO; 873 if (gso && virtio_has_feature(vdev, VIRTIO_NET_F_HOST_TSO6)) 874 dev->features |= NETIF_F_TSO6; 875 if (gso && virtio_has_feature(vdev, VIRTIO_NET_F_HOST_ECN)) 876 dev->features |= NETIF_F_TSO_ECN; 877 if (gso && virtio_has_feature(vdev, VIRTIO_NET_F_HOST_UFO)) 878 dev->features |= NETIF_F_UFO; 879 } 880 881 /* Configuration may specify what MAC to use. Otherwise random. */ 882 if (virtio_has_feature(vdev, VIRTIO_NET_F_MAC)) { 883 vdev->config->get(vdev, 884 offsetof(struct virtio_net_config, mac), 885 dev->dev_addr, dev->addr_len); 886 } else 887 random_ether_addr(dev->dev_addr); 888 889 /* Set up our device-specific information */ 890 vi = netdev_priv(dev); 891 netif_napi_add(dev, &vi->napi, virtnet_poll, napi_weight); 892 vi->dev = dev; 893 vi->vdev = vdev; 894 vdev->priv = vi; 895 vi->pages = NULL; 896 897 /* If they give us a callback when all buffers are done, we don't need 898 * the timer. */ 899 vi->free_in_tasklet = virtio_has_feature(vdev,VIRTIO_F_NOTIFY_ON_EMPTY); 900 901 /* If we can receive ANY GSO packets, we must allocate large ones. */ 902 if (virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_TSO4) 903 || virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_TSO6) 904 || virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_ECN)) 905 vi->big_packets = true; 906 907 if (virtio_has_feature(vdev, VIRTIO_NET_F_MRG_RXBUF)) 908 vi->mergeable_rx_bufs = true; 909 910 /* We expect two virtqueues, receive then send, 911 * and optionally control. */ 912 nvqs = virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ) ? 3 : 2; 913 914 err = vdev->config->find_vqs(vdev, nvqs, vqs, callbacks, names); 915 if (err) 916 goto free; 917 918 vi->rvq = vqs[0]; 919 vi->svq = vqs[1]; 920 921 if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ)) { 922 vi->cvq = vqs[2]; 923 924 if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VLAN)) 925 dev->features |= NETIF_F_HW_VLAN_FILTER; 926 } 927 928 /* Initialize our empty receive and send queues. */ 929 skb_queue_head_init(&vi->recv); 930 skb_queue_head_init(&vi->send); 931 932 tasklet_init(&vi->tasklet, xmit_tasklet, (unsigned long)vi); 933 934 if (!vi->free_in_tasklet) 935 setup_timer(&vi->xmit_free_timer, xmit_free, (unsigned long)vi); 936 937 err = register_netdev(dev); 938 if (err) { 939 pr_debug("virtio_net: registering device failed\n"); 940 goto free_vqs; 941 } 942 943 /* Last of all, set up some receive buffers. */ 944 try_fill_recv(vi); 945 946 /* If we didn't even get one input buffer, we're useless. */ 947 if (vi->num == 0) { 948 err = -ENOMEM; 949 goto unregister; 950 } 951 952 vi->status = VIRTIO_NET_S_LINK_UP; 953 virtnet_update_status(vi); 954 netif_carrier_on(dev); 955 956 pr_debug("virtnet: registered device %s\n", dev->name); 957 return 0; 958 959 unregister: 960 unregister_netdev(dev); 961 free_vqs: 962 vdev->config->del_vqs(vdev); 963 free: 964 free_netdev(dev); 965 return err; 966 } 967 968 static void virtnet_remove(struct virtio_device *vdev) 969 { 970 struct virtnet_info *vi = vdev->priv; 971 struct sk_buff *skb; 972 973 /* Stop all the virtqueues. */ 974 vdev->config->reset(vdev); 975 976 if (!vi->free_in_tasklet) 977 del_timer_sync(&vi->xmit_free_timer); 978 979 /* Free our skbs in send and recv queues, if any. */ 980 while ((skb = __skb_dequeue(&vi->recv)) != NULL) { 981 kfree_skb(skb); 982 vi->num--; 983 } 984 __skb_queue_purge(&vi->send); 985 986 BUG_ON(vi->num != 0); 987 988 unregister_netdev(vi->dev); 989 990 vdev->config->del_vqs(vi->vdev); 991 992 while (vi->pages) 993 __free_pages(get_a_page(vi, GFP_KERNEL), 0); 994 995 free_netdev(vi->dev); 996 } 997 998 static struct virtio_device_id id_table[] = { 999 { VIRTIO_ID_NET, VIRTIO_DEV_ANY_ID }, 1000 { 0 }, 1001 }; 1002 1003 static unsigned int features[] = { 1004 VIRTIO_NET_F_CSUM, VIRTIO_NET_F_GUEST_CSUM, 1005 VIRTIO_NET_F_GSO, VIRTIO_NET_F_MAC, 1006 VIRTIO_NET_F_HOST_TSO4, VIRTIO_NET_F_HOST_UFO, VIRTIO_NET_F_HOST_TSO6, 1007 VIRTIO_NET_F_HOST_ECN, VIRTIO_NET_F_GUEST_TSO4, VIRTIO_NET_F_GUEST_TSO6, 1008 VIRTIO_NET_F_GUEST_ECN, /* We don't yet handle UFO input. */ 1009 VIRTIO_NET_F_MRG_RXBUF, VIRTIO_NET_F_STATUS, VIRTIO_NET_F_CTRL_VQ, 1010 VIRTIO_NET_F_CTRL_RX, VIRTIO_NET_F_CTRL_VLAN, 1011 VIRTIO_F_NOTIFY_ON_EMPTY, 1012 }; 1013 1014 static struct virtio_driver virtio_net = { 1015 .feature_table = features, 1016 .feature_table_size = ARRAY_SIZE(features), 1017 .driver.name = KBUILD_MODNAME, 1018 .driver.owner = THIS_MODULE, 1019 .id_table = id_table, 1020 .probe = virtnet_probe, 1021 .remove = __devexit_p(virtnet_remove), 1022 .config_changed = virtnet_config_changed, 1023 }; 1024 1025 static int __init init(void) 1026 { 1027 return register_virtio_driver(&virtio_net); 1028 } 1029 1030 static void __exit fini(void) 1031 { 1032 unregister_virtio_driver(&virtio_net); 1033 } 1034 module_init(init); 1035 module_exit(fini); 1036 1037 MODULE_DEVICE_TABLE(virtio, id_table); 1038 MODULE_DESCRIPTION("Virtio network driver"); 1039 MODULE_LICENSE("GPL"); 1040