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