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 still_empty = !try_fill_recv(vi, GFP_KERNEL); 399 napi_enable(&vi->napi); 400 401 /* In theory, this can happen: if we don't get any buffers in 402 * we will *never* try to fill again. */ 403 if (still_empty) 404 schedule_delayed_work(&vi->refill, HZ/2); 405 } 406 407 static int virtnet_poll(struct napi_struct *napi, int budget) 408 { 409 struct virtnet_info *vi = container_of(napi, struct virtnet_info, napi); 410 struct sk_buff *skb = NULL; 411 unsigned int len, received = 0; 412 413 again: 414 while (received < budget && 415 (skb = vi->rvq->vq_ops->get_buf(vi->rvq, &len)) != NULL) { 416 __skb_unlink(skb, &vi->recv); 417 receive_skb(vi->dev, skb, len); 418 vi->num--; 419 received++; 420 } 421 422 if (vi->num < vi->max / 2) { 423 if (!try_fill_recv(vi, GFP_ATOMIC)) 424 schedule_delayed_work(&vi->refill, 0); 425 } 426 427 /* Out of packets? */ 428 if (received < budget) { 429 napi_complete(napi); 430 if (unlikely(!vi->rvq->vq_ops->enable_cb(vi->rvq)) && 431 napi_schedule_prep(napi)) { 432 vi->rvq->vq_ops->disable_cb(vi->rvq); 433 __napi_schedule(napi); 434 goto again; 435 } 436 } 437 438 return received; 439 } 440 441 static unsigned int free_old_xmit_skbs(struct virtnet_info *vi) 442 { 443 struct sk_buff *skb; 444 unsigned int len, tot_sgs = 0; 445 446 while ((skb = vi->svq->vq_ops->get_buf(vi->svq, &len)) != NULL) { 447 pr_debug("Sent skb %p\n", skb); 448 __skb_unlink(skb, &vi->send); 449 vi->dev->stats.tx_bytes += skb->len; 450 vi->dev->stats.tx_packets++; 451 tot_sgs += skb_vnet_hdr(skb)->num_sg; 452 dev_kfree_skb_any(skb); 453 } 454 return tot_sgs; 455 } 456 457 static int xmit_skb(struct virtnet_info *vi, struct sk_buff *skb) 458 { 459 struct scatterlist sg[2+MAX_SKB_FRAGS]; 460 struct skb_vnet_hdr *hdr = skb_vnet_hdr(skb); 461 const unsigned char *dest = ((struct ethhdr *)skb->data)->h_dest; 462 463 sg_init_table(sg, 2+MAX_SKB_FRAGS); 464 465 pr_debug("%s: xmit %p %pM\n", vi->dev->name, skb, dest); 466 467 if (skb->ip_summed == CHECKSUM_PARTIAL) { 468 hdr->hdr.flags = VIRTIO_NET_HDR_F_NEEDS_CSUM; 469 hdr->hdr.csum_start = skb->csum_start - skb_headroom(skb); 470 hdr->hdr.csum_offset = skb->csum_offset; 471 } else { 472 hdr->hdr.flags = 0; 473 hdr->hdr.csum_offset = hdr->hdr.csum_start = 0; 474 } 475 476 if (skb_is_gso(skb)) { 477 hdr->hdr.hdr_len = skb_headlen(skb); 478 hdr->hdr.gso_size = skb_shinfo(skb)->gso_size; 479 if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV4) 480 hdr->hdr.gso_type = VIRTIO_NET_HDR_GSO_TCPV4; 481 else if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV6) 482 hdr->hdr.gso_type = VIRTIO_NET_HDR_GSO_TCPV6; 483 else if (skb_shinfo(skb)->gso_type & SKB_GSO_UDP) 484 hdr->hdr.gso_type = VIRTIO_NET_HDR_GSO_UDP; 485 else 486 BUG(); 487 if (skb_shinfo(skb)->gso_type & SKB_GSO_TCP_ECN) 488 hdr->hdr.gso_type |= VIRTIO_NET_HDR_GSO_ECN; 489 } else { 490 hdr->hdr.gso_type = VIRTIO_NET_HDR_GSO_NONE; 491 hdr->hdr.gso_size = hdr->hdr.hdr_len = 0; 492 } 493 494 hdr->mhdr.num_buffers = 0; 495 496 /* Encode metadata header at front. */ 497 if (vi->mergeable_rx_bufs) 498 sg_set_buf(sg, &hdr->mhdr, sizeof(hdr->mhdr)); 499 else 500 sg_set_buf(sg, &hdr->hdr, sizeof(hdr->hdr)); 501 502 hdr->num_sg = skb_to_sgvec(skb, sg+1, 0, skb->len) + 1; 503 return vi->svq->vq_ops->add_buf(vi->svq, sg, hdr->num_sg, 0, skb); 504 } 505 506 static netdev_tx_t start_xmit(struct sk_buff *skb, struct net_device *dev) 507 { 508 struct virtnet_info *vi = netdev_priv(dev); 509 int capacity; 510 511 again: 512 /* Free up any pending old buffers before queueing new ones. */ 513 free_old_xmit_skbs(vi); 514 515 /* Try to transmit */ 516 capacity = xmit_skb(vi, skb); 517 518 /* This can happen with OOM and indirect buffers. */ 519 if (unlikely(capacity < 0)) { 520 netif_stop_queue(dev); 521 dev_warn(&dev->dev, "Unexpected full queue\n"); 522 if (unlikely(!vi->svq->vq_ops->enable_cb(vi->svq))) { 523 vi->svq->vq_ops->disable_cb(vi->svq); 524 netif_start_queue(dev); 525 goto again; 526 } 527 return NETDEV_TX_BUSY; 528 } 529 vi->svq->vq_ops->kick(vi->svq); 530 531 /* 532 * Put new one in send queue. You'd expect we'd need this before 533 * xmit_skb calls add_buf(), since the callback can be triggered 534 * immediately after that. But since the callback just triggers 535 * another call back here, normal network xmit locking prevents the 536 * race. 537 */ 538 __skb_queue_head(&vi->send, skb); 539 540 /* Don't wait up for transmitted skbs to be freed. */ 541 skb_orphan(skb); 542 nf_reset(skb); 543 544 /* Apparently nice girls don't return TX_BUSY; stop the queue 545 * before it gets out of hand. Naturally, this wastes entries. */ 546 if (capacity < 2+MAX_SKB_FRAGS) { 547 netif_stop_queue(dev); 548 if (unlikely(!vi->svq->vq_ops->enable_cb(vi->svq))) { 549 /* More just got used, free them then recheck. */ 550 capacity += free_old_xmit_skbs(vi); 551 if (capacity >= 2+MAX_SKB_FRAGS) { 552 netif_start_queue(dev); 553 vi->svq->vq_ops->disable_cb(vi->svq); 554 } 555 } 556 } 557 558 return NETDEV_TX_OK; 559 } 560 561 static int virtnet_set_mac_address(struct net_device *dev, void *p) 562 { 563 struct virtnet_info *vi = netdev_priv(dev); 564 struct virtio_device *vdev = vi->vdev; 565 int ret; 566 567 ret = eth_mac_addr(dev, p); 568 if (ret) 569 return ret; 570 571 if (virtio_has_feature(vdev, VIRTIO_NET_F_MAC)) 572 vdev->config->set(vdev, offsetof(struct virtio_net_config, mac), 573 dev->dev_addr, dev->addr_len); 574 575 return 0; 576 } 577 578 #ifdef CONFIG_NET_POLL_CONTROLLER 579 static void virtnet_netpoll(struct net_device *dev) 580 { 581 struct virtnet_info *vi = netdev_priv(dev); 582 583 napi_schedule(&vi->napi); 584 } 585 #endif 586 587 static int virtnet_open(struct net_device *dev) 588 { 589 struct virtnet_info *vi = netdev_priv(dev); 590 591 napi_enable(&vi->napi); 592 593 /* If all buffers were filled by other side before we napi_enabled, we 594 * won't get another interrupt, so process any outstanding packets 595 * now. virtnet_poll wants re-enable the queue, so we disable here. 596 * We synchronize against interrupts via NAPI_STATE_SCHED */ 597 if (napi_schedule_prep(&vi->napi)) { 598 vi->rvq->vq_ops->disable_cb(vi->rvq); 599 __napi_schedule(&vi->napi); 600 } 601 return 0; 602 } 603 604 /* 605 * Send command via the control virtqueue and check status. Commands 606 * supported by the hypervisor, as indicated by feature bits, should 607 * never fail unless improperly formated. 608 */ 609 static bool virtnet_send_command(struct virtnet_info *vi, u8 class, u8 cmd, 610 struct scatterlist *data, int out, int in) 611 { 612 struct scatterlist *s, sg[VIRTNET_SEND_COMMAND_SG_MAX + 2]; 613 struct virtio_net_ctrl_hdr ctrl; 614 virtio_net_ctrl_ack status = ~0; 615 unsigned int tmp; 616 int i; 617 618 /* Caller should know better */ 619 BUG_ON(!virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ) || 620 (out + in > VIRTNET_SEND_COMMAND_SG_MAX)); 621 622 out++; /* Add header */ 623 in++; /* Add return status */ 624 625 ctrl.class = class; 626 ctrl.cmd = cmd; 627 628 sg_init_table(sg, out + in); 629 630 sg_set_buf(&sg[0], &ctrl, sizeof(ctrl)); 631 for_each_sg(data, s, out + in - 2, i) 632 sg_set_buf(&sg[i + 1], sg_virt(s), s->length); 633 sg_set_buf(&sg[out + in - 1], &status, sizeof(status)); 634 635 BUG_ON(vi->cvq->vq_ops->add_buf(vi->cvq, sg, out, in, vi) < 0); 636 637 vi->cvq->vq_ops->kick(vi->cvq); 638 639 /* 640 * Spin for a response, the kick causes an ioport write, trapping 641 * into the hypervisor, so the request should be handled immediately. 642 */ 643 while (!vi->cvq->vq_ops->get_buf(vi->cvq, &tmp)) 644 cpu_relax(); 645 646 return status == VIRTIO_NET_OK; 647 } 648 649 static int virtnet_close(struct net_device *dev) 650 { 651 struct virtnet_info *vi = netdev_priv(dev); 652 653 napi_disable(&vi->napi); 654 655 return 0; 656 } 657 658 static int virtnet_set_tx_csum(struct net_device *dev, u32 data) 659 { 660 struct virtnet_info *vi = netdev_priv(dev); 661 struct virtio_device *vdev = vi->vdev; 662 663 if (data && !virtio_has_feature(vdev, VIRTIO_NET_F_CSUM)) 664 return -ENOSYS; 665 666 return ethtool_op_set_tx_hw_csum(dev, data); 667 } 668 669 static void virtnet_set_rx_mode(struct net_device *dev) 670 { 671 struct virtnet_info *vi = netdev_priv(dev); 672 struct scatterlist sg[2]; 673 u8 promisc, allmulti; 674 struct virtio_net_ctrl_mac *mac_data; 675 struct dev_addr_list *addr; 676 struct netdev_hw_addr *ha; 677 void *buf; 678 int i; 679 680 /* We can't dynamicaly set ndo_set_rx_mode, so return gracefully */ 681 if (!virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_RX)) 682 return; 683 684 promisc = ((dev->flags & IFF_PROMISC) != 0); 685 allmulti = ((dev->flags & IFF_ALLMULTI) != 0); 686 687 sg_init_one(sg, &promisc, sizeof(promisc)); 688 689 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_RX, 690 VIRTIO_NET_CTRL_RX_PROMISC, 691 sg, 1, 0)) 692 dev_warn(&dev->dev, "Failed to %sable promisc mode.\n", 693 promisc ? "en" : "dis"); 694 695 sg_init_one(sg, &allmulti, sizeof(allmulti)); 696 697 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_RX, 698 VIRTIO_NET_CTRL_RX_ALLMULTI, 699 sg, 1, 0)) 700 dev_warn(&dev->dev, "Failed to %sable allmulti mode.\n", 701 allmulti ? "en" : "dis"); 702 703 /* MAC filter - use one buffer for both lists */ 704 mac_data = buf = kzalloc(((dev->uc.count + dev->mc_count) * ETH_ALEN) + 705 (2 * sizeof(mac_data->entries)), GFP_ATOMIC); 706 if (!buf) { 707 dev_warn(&dev->dev, "No memory for MAC address buffer\n"); 708 return; 709 } 710 711 sg_init_table(sg, 2); 712 713 /* Store the unicast list and count in the front of the buffer */ 714 mac_data->entries = dev->uc.count; 715 i = 0; 716 list_for_each_entry(ha, &dev->uc.list, list) 717 memcpy(&mac_data->macs[i++][0], ha->addr, ETH_ALEN); 718 719 sg_set_buf(&sg[0], mac_data, 720 sizeof(mac_data->entries) + (dev->uc.count * ETH_ALEN)); 721 722 /* multicast list and count fill the end */ 723 mac_data = (void *)&mac_data->macs[dev->uc.count][0]; 724 725 mac_data->entries = dev->mc_count; 726 addr = dev->mc_list; 727 for (i = 0; i < dev->mc_count; i++, addr = addr->next) 728 memcpy(&mac_data->macs[i][0], addr->da_addr, ETH_ALEN); 729 730 sg_set_buf(&sg[1], mac_data, 731 sizeof(mac_data->entries) + (dev->mc_count * ETH_ALEN)); 732 733 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_MAC, 734 VIRTIO_NET_CTRL_MAC_TABLE_SET, 735 sg, 2, 0)) 736 dev_warn(&dev->dev, "Failed to set MAC fitler table.\n"); 737 738 kfree(buf); 739 } 740 741 static void virtnet_vlan_rx_add_vid(struct net_device *dev, u16 vid) 742 { 743 struct virtnet_info *vi = netdev_priv(dev); 744 struct scatterlist sg; 745 746 sg_init_one(&sg, &vid, sizeof(vid)); 747 748 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_VLAN, 749 VIRTIO_NET_CTRL_VLAN_ADD, &sg, 1, 0)) 750 dev_warn(&dev->dev, "Failed to add VLAN ID %d.\n", vid); 751 } 752 753 static void virtnet_vlan_rx_kill_vid(struct net_device *dev, u16 vid) 754 { 755 struct virtnet_info *vi = netdev_priv(dev); 756 struct scatterlist sg; 757 758 sg_init_one(&sg, &vid, sizeof(vid)); 759 760 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_VLAN, 761 VIRTIO_NET_CTRL_VLAN_DEL, &sg, 1, 0)) 762 dev_warn(&dev->dev, "Failed to kill VLAN ID %d.\n", vid); 763 } 764 765 static const struct ethtool_ops virtnet_ethtool_ops = { 766 .set_tx_csum = virtnet_set_tx_csum, 767 .set_sg = ethtool_op_set_sg, 768 .set_tso = ethtool_op_set_tso, 769 .set_ufo = ethtool_op_set_ufo, 770 .get_link = ethtool_op_get_link, 771 }; 772 773 #define MIN_MTU 68 774 #define MAX_MTU 65535 775 776 static int virtnet_change_mtu(struct net_device *dev, int new_mtu) 777 { 778 if (new_mtu < MIN_MTU || new_mtu > MAX_MTU) 779 return -EINVAL; 780 dev->mtu = new_mtu; 781 return 0; 782 } 783 784 static const struct net_device_ops virtnet_netdev = { 785 .ndo_open = virtnet_open, 786 .ndo_stop = virtnet_close, 787 .ndo_start_xmit = start_xmit, 788 .ndo_validate_addr = eth_validate_addr, 789 .ndo_set_mac_address = virtnet_set_mac_address, 790 .ndo_set_rx_mode = virtnet_set_rx_mode, 791 .ndo_change_mtu = virtnet_change_mtu, 792 .ndo_vlan_rx_add_vid = virtnet_vlan_rx_add_vid, 793 .ndo_vlan_rx_kill_vid = virtnet_vlan_rx_kill_vid, 794 #ifdef CONFIG_NET_POLL_CONTROLLER 795 .ndo_poll_controller = virtnet_netpoll, 796 #endif 797 }; 798 799 static void virtnet_update_status(struct virtnet_info *vi) 800 { 801 u16 v; 802 803 if (!virtio_has_feature(vi->vdev, VIRTIO_NET_F_STATUS)) 804 return; 805 806 vi->vdev->config->get(vi->vdev, 807 offsetof(struct virtio_net_config, status), 808 &v, sizeof(v)); 809 810 /* Ignore unknown (future) status bits */ 811 v &= VIRTIO_NET_S_LINK_UP; 812 813 if (vi->status == v) 814 return; 815 816 vi->status = v; 817 818 if (vi->status & VIRTIO_NET_S_LINK_UP) { 819 netif_carrier_on(vi->dev); 820 netif_wake_queue(vi->dev); 821 } else { 822 netif_carrier_off(vi->dev); 823 netif_stop_queue(vi->dev); 824 } 825 } 826 827 static void virtnet_config_changed(struct virtio_device *vdev) 828 { 829 struct virtnet_info *vi = vdev->priv; 830 831 virtnet_update_status(vi); 832 } 833 834 static int virtnet_probe(struct virtio_device *vdev) 835 { 836 int err; 837 struct net_device *dev; 838 struct virtnet_info *vi; 839 struct virtqueue *vqs[3]; 840 vq_callback_t *callbacks[] = { skb_recv_done, skb_xmit_done, NULL}; 841 const char *names[] = { "input", "output", "control" }; 842 int nvqs; 843 844 /* Allocate ourselves a network device with room for our info */ 845 dev = alloc_etherdev(sizeof(struct virtnet_info)); 846 if (!dev) 847 return -ENOMEM; 848 849 /* Set up network device as normal. */ 850 dev->netdev_ops = &virtnet_netdev; 851 dev->features = NETIF_F_HIGHDMA; 852 SET_ETHTOOL_OPS(dev, &virtnet_ethtool_ops); 853 SET_NETDEV_DEV(dev, &vdev->dev); 854 855 /* Do we support "hardware" checksums? */ 856 if (csum && virtio_has_feature(vdev, VIRTIO_NET_F_CSUM)) { 857 /* This opens up the world of extra features. */ 858 dev->features |= NETIF_F_HW_CSUM|NETIF_F_SG|NETIF_F_FRAGLIST; 859 if (gso && virtio_has_feature(vdev, VIRTIO_NET_F_GSO)) { 860 dev->features |= NETIF_F_TSO | NETIF_F_UFO 861 | NETIF_F_TSO_ECN | NETIF_F_TSO6; 862 } 863 /* Individual feature bits: what can host handle? */ 864 if (gso && virtio_has_feature(vdev, VIRTIO_NET_F_HOST_TSO4)) 865 dev->features |= NETIF_F_TSO; 866 if (gso && virtio_has_feature(vdev, VIRTIO_NET_F_HOST_TSO6)) 867 dev->features |= NETIF_F_TSO6; 868 if (gso && virtio_has_feature(vdev, VIRTIO_NET_F_HOST_ECN)) 869 dev->features |= NETIF_F_TSO_ECN; 870 if (gso && virtio_has_feature(vdev, VIRTIO_NET_F_HOST_UFO)) 871 dev->features |= NETIF_F_UFO; 872 } 873 874 /* Configuration may specify what MAC to use. Otherwise random. */ 875 if (virtio_has_feature(vdev, VIRTIO_NET_F_MAC)) { 876 vdev->config->get(vdev, 877 offsetof(struct virtio_net_config, mac), 878 dev->dev_addr, dev->addr_len); 879 } else 880 random_ether_addr(dev->dev_addr); 881 882 /* Set up our device-specific information */ 883 vi = netdev_priv(dev); 884 netif_napi_add(dev, &vi->napi, virtnet_poll, napi_weight); 885 vi->dev = dev; 886 vi->vdev = vdev; 887 vdev->priv = vi; 888 vi->pages = NULL; 889 INIT_DELAYED_WORK(&vi->refill, refill_work); 890 891 /* If we can receive ANY GSO packets, we must allocate large ones. */ 892 if (virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_TSO4) || 893 virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_TSO6) || 894 virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_ECN)) 895 vi->big_packets = true; 896 897 if (virtio_has_feature(vdev, VIRTIO_NET_F_MRG_RXBUF)) 898 vi->mergeable_rx_bufs = true; 899 900 /* We expect two virtqueues, receive then send, 901 * and optionally control. */ 902 nvqs = virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ) ? 3 : 2; 903 904 err = vdev->config->find_vqs(vdev, nvqs, vqs, callbacks, names); 905 if (err) 906 goto free; 907 908 vi->rvq = vqs[0]; 909 vi->svq = vqs[1]; 910 911 if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ)) { 912 vi->cvq = vqs[2]; 913 914 if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VLAN)) 915 dev->features |= NETIF_F_HW_VLAN_FILTER; 916 } 917 918 /* Initialize our empty receive and send queues. */ 919 skb_queue_head_init(&vi->recv); 920 skb_queue_head_init(&vi->send); 921 922 err = register_netdev(dev); 923 if (err) { 924 pr_debug("virtio_net: registering device failed\n"); 925 goto free_vqs; 926 } 927 928 /* Last of all, set up some receive buffers. */ 929 try_fill_recv(vi, GFP_KERNEL); 930 931 /* If we didn't even get one input buffer, we're useless. */ 932 if (vi->num == 0) { 933 err = -ENOMEM; 934 goto unregister; 935 } 936 937 vi->status = VIRTIO_NET_S_LINK_UP; 938 virtnet_update_status(vi); 939 netif_carrier_on(dev); 940 941 pr_debug("virtnet: registered device %s\n", dev->name); 942 return 0; 943 944 unregister: 945 unregister_netdev(dev); 946 cancel_delayed_work_sync(&vi->refill); 947 free_vqs: 948 vdev->config->del_vqs(vdev); 949 free: 950 free_netdev(dev); 951 return err; 952 } 953 954 static void __devexit virtnet_remove(struct virtio_device *vdev) 955 { 956 struct virtnet_info *vi = vdev->priv; 957 struct sk_buff *skb; 958 959 /* Stop all the virtqueues. */ 960 vdev->config->reset(vdev); 961 962 /* Free our skbs in send and recv queues, if any. */ 963 while ((skb = __skb_dequeue(&vi->recv)) != NULL) { 964 kfree_skb(skb); 965 vi->num--; 966 } 967 __skb_queue_purge(&vi->send); 968 969 BUG_ON(vi->num != 0); 970 971 unregister_netdev(vi->dev); 972 cancel_delayed_work_sync(&vi->refill); 973 974 vdev->config->del_vqs(vi->vdev); 975 976 while (vi->pages) 977 __free_pages(get_a_page(vi, GFP_KERNEL), 0); 978 979 free_netdev(vi->dev); 980 } 981 982 static struct virtio_device_id id_table[] = { 983 { VIRTIO_ID_NET, VIRTIO_DEV_ANY_ID }, 984 { 0 }, 985 }; 986 987 static unsigned int features[] = { 988 VIRTIO_NET_F_CSUM, VIRTIO_NET_F_GUEST_CSUM, 989 VIRTIO_NET_F_GSO, VIRTIO_NET_F_MAC, 990 VIRTIO_NET_F_HOST_TSO4, VIRTIO_NET_F_HOST_UFO, VIRTIO_NET_F_HOST_TSO6, 991 VIRTIO_NET_F_HOST_ECN, VIRTIO_NET_F_GUEST_TSO4, VIRTIO_NET_F_GUEST_TSO6, 992 VIRTIO_NET_F_GUEST_ECN, VIRTIO_NET_F_GUEST_UFO, 993 VIRTIO_NET_F_MRG_RXBUF, VIRTIO_NET_F_STATUS, VIRTIO_NET_F_CTRL_VQ, 994 VIRTIO_NET_F_CTRL_RX, VIRTIO_NET_F_CTRL_VLAN, 995 }; 996 997 static struct virtio_driver virtio_net_driver = { 998 .feature_table = features, 999 .feature_table_size = ARRAY_SIZE(features), 1000 .driver.name = KBUILD_MODNAME, 1001 .driver.owner = THIS_MODULE, 1002 .id_table = id_table, 1003 .probe = virtnet_probe, 1004 .remove = __devexit_p(virtnet_remove), 1005 .config_changed = virtnet_config_changed, 1006 }; 1007 1008 static int __init init(void) 1009 { 1010 return register_virtio_driver(&virtio_net_driver); 1011 } 1012 1013 static void __exit fini(void) 1014 { 1015 unregister_virtio_driver(&virtio_net_driver); 1016 } 1017 module_init(init); 1018 module_exit(fini); 1019 1020 MODULE_DEVICE_TABLE(virtio, id_table); 1021 MODULE_DESCRIPTION("Virtio network driver"); 1022 MODULE_LICENSE("GPL"); 1023