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