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(vi->dev, MAX_PACKET_LEN + NET_IP_ALIGN); 286 if (unlikely(!skb)) { 287 oom = true; 288 break; 289 } 290 291 skb_reserve(skb, NET_IP_ALIGN); 292 skb_put(skb, MAX_PACKET_LEN); 293 294 hdr = skb_vnet_hdr(skb); 295 sg_set_buf(sg, &hdr->hdr, sizeof(hdr->hdr)); 296 297 if (vi->big_packets) { 298 for (i = 0; i < MAX_SKB_FRAGS; i++) { 299 skb_frag_t *f = &skb_shinfo(skb)->frags[i]; 300 f->page = get_a_page(vi, gfp); 301 if (!f->page) 302 break; 303 304 f->page_offset = 0; 305 f->size = PAGE_SIZE; 306 307 skb->data_len += PAGE_SIZE; 308 skb->len += PAGE_SIZE; 309 310 skb_shinfo(skb)->nr_frags++; 311 } 312 } 313 314 num = skb_to_sgvec(skb, sg+1, 0, skb->len) + 1; 315 skb_queue_head(&vi->recv, skb); 316 317 err = vi->rvq->vq_ops->add_buf(vi->rvq, sg, 0, num, skb); 318 if (err < 0) { 319 skb_unlink(skb, &vi->recv); 320 trim_pages(vi, skb); 321 kfree_skb(skb); 322 break; 323 } 324 vi->num++; 325 } while (err >= num); 326 if (unlikely(vi->num > vi->max)) 327 vi->max = vi->num; 328 vi->rvq->vq_ops->kick(vi->rvq); 329 return !oom; 330 } 331 332 /* Returns false if we couldn't fill entirely (OOM). */ 333 static bool try_fill_recv(struct virtnet_info *vi, gfp_t gfp) 334 { 335 struct sk_buff *skb; 336 struct scatterlist sg[1]; 337 int err; 338 bool oom = false; 339 340 if (!vi->mergeable_rx_bufs) 341 return try_fill_recv_maxbufs(vi, gfp); 342 343 do { 344 skb_frag_t *f; 345 346 skb = netdev_alloc_skb(vi->dev, GOOD_COPY_LEN + NET_IP_ALIGN); 347 if (unlikely(!skb)) { 348 oom = true; 349 break; 350 } 351 352 skb_reserve(skb, NET_IP_ALIGN); 353 354 f = &skb_shinfo(skb)->frags[0]; 355 f->page = get_a_page(vi, gfp); 356 if (!f->page) { 357 oom = true; 358 kfree_skb(skb); 359 break; 360 } 361 362 f->page_offset = 0; 363 f->size = PAGE_SIZE; 364 365 skb_shinfo(skb)->nr_frags++; 366 367 sg_init_one(sg, page_address(f->page), PAGE_SIZE); 368 skb_queue_head(&vi->recv, skb); 369 370 err = vi->rvq->vq_ops->add_buf(vi->rvq, sg, 0, 1, skb); 371 if (err < 0) { 372 skb_unlink(skb, &vi->recv); 373 kfree_skb(skb); 374 break; 375 } 376 vi->num++; 377 } while (err > 0); 378 if (unlikely(vi->num > vi->max)) 379 vi->max = vi->num; 380 vi->rvq->vq_ops->kick(vi->rvq); 381 return !oom; 382 } 383 384 static void skb_recv_done(struct virtqueue *rvq) 385 { 386 struct virtnet_info *vi = rvq->vdev->priv; 387 /* Schedule NAPI, Suppress further interrupts if successful. */ 388 if (napi_schedule_prep(&vi->napi)) { 389 rvq->vq_ops->disable_cb(rvq); 390 __napi_schedule(&vi->napi); 391 } 392 } 393 394 static void refill_work(struct work_struct *work) 395 { 396 struct virtnet_info *vi; 397 bool still_empty; 398 399 vi = container_of(work, struct virtnet_info, refill.work); 400 napi_disable(&vi->napi); 401 try_fill_recv(vi, GFP_KERNEL); 402 still_empty = (vi->num == 0); 403 napi_enable(&vi->napi); 404 405 /* In theory, this can happen: if we don't get any buffers in 406 * we will *never* try to fill again. */ 407 if (still_empty) 408 schedule_delayed_work(&vi->refill, HZ/2); 409 } 410 411 static int virtnet_poll(struct napi_struct *napi, int budget) 412 { 413 struct virtnet_info *vi = container_of(napi, struct virtnet_info, napi); 414 struct sk_buff *skb = NULL; 415 unsigned int len, received = 0; 416 417 again: 418 while (received < budget && 419 (skb = vi->rvq->vq_ops->get_buf(vi->rvq, &len)) != NULL) { 420 __skb_unlink(skb, &vi->recv); 421 receive_skb(vi->dev, skb, len); 422 vi->num--; 423 received++; 424 } 425 426 if (vi->num < vi->max / 2) { 427 if (!try_fill_recv(vi, GFP_ATOMIC)) 428 schedule_delayed_work(&vi->refill, 0); 429 } 430 431 /* Out of packets? */ 432 if (received < budget) { 433 napi_complete(napi); 434 if (unlikely(!vi->rvq->vq_ops->enable_cb(vi->rvq)) 435 && napi_schedule_prep(napi)) { 436 vi->rvq->vq_ops->disable_cb(vi->rvq); 437 __napi_schedule(napi); 438 goto again; 439 } 440 } 441 442 return received; 443 } 444 445 static unsigned int free_old_xmit_skbs(struct virtnet_info *vi) 446 { 447 struct sk_buff *skb; 448 unsigned int len, tot_sgs = 0; 449 450 while ((skb = vi->svq->vq_ops->get_buf(vi->svq, &len)) != NULL) { 451 pr_debug("Sent skb %p\n", skb); 452 __skb_unlink(skb, &vi->send); 453 vi->dev->stats.tx_bytes += skb->len; 454 vi->dev->stats.tx_packets++; 455 tot_sgs += skb_vnet_hdr(skb)->num_sg; 456 dev_kfree_skb_any(skb); 457 } 458 return tot_sgs; 459 } 460 461 static int xmit_skb(struct virtnet_info *vi, struct sk_buff *skb) 462 { 463 struct scatterlist sg[2+MAX_SKB_FRAGS]; 464 struct skb_vnet_hdr *hdr = skb_vnet_hdr(skb); 465 const unsigned char *dest = ((struct ethhdr *)skb->data)->h_dest; 466 467 sg_init_table(sg, 2+MAX_SKB_FRAGS); 468 469 pr_debug("%s: xmit %p %pM\n", vi->dev->name, skb, dest); 470 471 if (skb->ip_summed == CHECKSUM_PARTIAL) { 472 hdr->hdr.flags = VIRTIO_NET_HDR_F_NEEDS_CSUM; 473 hdr->hdr.csum_start = skb->csum_start - skb_headroom(skb); 474 hdr->hdr.csum_offset = skb->csum_offset; 475 } else { 476 hdr->hdr.flags = 0; 477 hdr->hdr.csum_offset = hdr->hdr.csum_start = 0; 478 } 479 480 if (skb_is_gso(skb)) { 481 hdr->hdr.hdr_len = skb_headlen(skb); 482 hdr->hdr.gso_size = skb_shinfo(skb)->gso_size; 483 if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV4) 484 hdr->hdr.gso_type = VIRTIO_NET_HDR_GSO_TCPV4; 485 else if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV6) 486 hdr->hdr.gso_type = VIRTIO_NET_HDR_GSO_TCPV6; 487 else if (skb_shinfo(skb)->gso_type & SKB_GSO_UDP) 488 hdr->hdr.gso_type = VIRTIO_NET_HDR_GSO_UDP; 489 else 490 BUG(); 491 if (skb_shinfo(skb)->gso_type & SKB_GSO_TCP_ECN) 492 hdr->hdr.gso_type |= VIRTIO_NET_HDR_GSO_ECN; 493 } else { 494 hdr->hdr.gso_type = VIRTIO_NET_HDR_GSO_NONE; 495 hdr->hdr.gso_size = hdr->hdr.hdr_len = 0; 496 } 497 498 hdr->mhdr.num_buffers = 0; 499 500 /* Encode metadata header at front. */ 501 if (vi->mergeable_rx_bufs) 502 sg_set_buf(sg, &hdr->mhdr, sizeof(hdr->mhdr)); 503 else 504 sg_set_buf(sg, &hdr->hdr, sizeof(hdr->hdr)); 505 506 hdr->num_sg = skb_to_sgvec(skb, sg+1, 0, skb->len) + 1; 507 return vi->svq->vq_ops->add_buf(vi->svq, sg, hdr->num_sg, 0, skb); 508 } 509 510 static netdev_tx_t start_xmit(struct sk_buff *skb, struct net_device *dev) 511 { 512 struct virtnet_info *vi = netdev_priv(dev); 513 int capacity; 514 515 again: 516 /* Free up any pending old buffers before queueing new ones. */ 517 free_old_xmit_skbs(vi); 518 519 /* Try to transmit */ 520 capacity = xmit_skb(vi, skb); 521 522 /* This can happen with OOM and indirect buffers. */ 523 if (unlikely(capacity < 0)) { 524 netif_stop_queue(dev); 525 dev_warn(&dev->dev, "Unexpected full queue\n"); 526 if (unlikely(!vi->svq->vq_ops->enable_cb(vi->svq))) { 527 vi->svq->vq_ops->disable_cb(vi->svq); 528 netif_start_queue(dev); 529 goto again; 530 } 531 return NETDEV_TX_BUSY; 532 } 533 vi->svq->vq_ops->kick(vi->svq); 534 535 /* 536 * Put new one in send queue. You'd expect we'd need this before 537 * xmit_skb calls add_buf(), since the callback can be triggered 538 * immediately after that. But since the callback just triggers 539 * another call back here, normal network xmit locking prevents the 540 * race. 541 */ 542 __skb_queue_head(&vi->send, skb); 543 544 /* Don't wait up for transmitted skbs to be freed. */ 545 skb_orphan(skb); 546 nf_reset(skb); 547 548 /* Apparently nice girls don't return TX_BUSY; stop the queue 549 * before it gets out of hand. Naturally, this wastes entries. */ 550 if (capacity < 2+MAX_SKB_FRAGS) { 551 netif_stop_queue(dev); 552 if (unlikely(!vi->svq->vq_ops->enable_cb(vi->svq))) { 553 /* More just got used, free them then recheck. */ 554 capacity += free_old_xmit_skbs(vi); 555 if (capacity >= 2+MAX_SKB_FRAGS) { 556 netif_start_queue(dev); 557 vi->svq->vq_ops->disable_cb(vi->svq); 558 } 559 } 560 } 561 562 return NETDEV_TX_OK; 563 } 564 565 static int virtnet_set_mac_address(struct net_device *dev, void *p) 566 { 567 struct virtnet_info *vi = netdev_priv(dev); 568 struct virtio_device *vdev = vi->vdev; 569 int ret; 570 571 ret = eth_mac_addr(dev, p); 572 if (ret) 573 return ret; 574 575 if (virtio_has_feature(vdev, VIRTIO_NET_F_MAC)) 576 vdev->config->set(vdev, offsetof(struct virtio_net_config, mac), 577 dev->dev_addr, dev->addr_len); 578 579 return 0; 580 } 581 582 #ifdef CONFIG_NET_POLL_CONTROLLER 583 static void virtnet_netpoll(struct net_device *dev) 584 { 585 struct virtnet_info *vi = netdev_priv(dev); 586 587 napi_schedule(&vi->napi); 588 } 589 #endif 590 591 static int virtnet_open(struct net_device *dev) 592 { 593 struct virtnet_info *vi = netdev_priv(dev); 594 595 napi_enable(&vi->napi); 596 597 /* If all buffers were filled by other side before we napi_enabled, we 598 * won't get another interrupt, so process any outstanding packets 599 * now. virtnet_poll wants re-enable the queue, so we disable here. 600 * We synchronize against interrupts via NAPI_STATE_SCHED */ 601 if (napi_schedule_prep(&vi->napi)) { 602 vi->rvq->vq_ops->disable_cb(vi->rvq); 603 __napi_schedule(&vi->napi); 604 } 605 return 0; 606 } 607 608 /* 609 * Send command via the control virtqueue and check status. Commands 610 * supported by the hypervisor, as indicated by feature bits, should 611 * never fail unless improperly formated. 612 */ 613 static bool virtnet_send_command(struct virtnet_info *vi, u8 class, u8 cmd, 614 struct scatterlist *data, int out, int in) 615 { 616 struct scatterlist *s, sg[VIRTNET_SEND_COMMAND_SG_MAX + 2]; 617 struct virtio_net_ctrl_hdr ctrl; 618 virtio_net_ctrl_ack status = ~0; 619 unsigned int tmp; 620 int i; 621 622 /* Caller should know better */ 623 BUG_ON(!virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ) || 624 (out + in > VIRTNET_SEND_COMMAND_SG_MAX)); 625 626 out++; /* Add header */ 627 in++; /* Add return status */ 628 629 ctrl.class = class; 630 ctrl.cmd = cmd; 631 632 sg_init_table(sg, out + in); 633 634 sg_set_buf(&sg[0], &ctrl, sizeof(ctrl)); 635 for_each_sg(data, s, out + in - 2, i) 636 sg_set_buf(&sg[i + 1], sg_virt(s), s->length); 637 sg_set_buf(&sg[out + in - 1], &status, sizeof(status)); 638 639 BUG_ON(vi->cvq->vq_ops->add_buf(vi->cvq, sg, out, in, vi) < 0); 640 641 vi->cvq->vq_ops->kick(vi->cvq); 642 643 /* 644 * Spin for a response, the kick causes an ioport write, trapping 645 * into the hypervisor, so the request should be handled immediately. 646 */ 647 while (!vi->cvq->vq_ops->get_buf(vi->cvq, &tmp)) 648 cpu_relax(); 649 650 return status == VIRTIO_NET_OK; 651 } 652 653 static int virtnet_close(struct net_device *dev) 654 { 655 struct virtnet_info *vi = netdev_priv(dev); 656 657 napi_disable(&vi->napi); 658 659 return 0; 660 } 661 662 static int virtnet_set_tx_csum(struct net_device *dev, u32 data) 663 { 664 struct virtnet_info *vi = netdev_priv(dev); 665 struct virtio_device *vdev = vi->vdev; 666 667 if (data && !virtio_has_feature(vdev, VIRTIO_NET_F_CSUM)) 668 return -ENOSYS; 669 670 return ethtool_op_set_tx_hw_csum(dev, data); 671 } 672 673 static void virtnet_set_rx_mode(struct net_device *dev) 674 { 675 struct virtnet_info *vi = netdev_priv(dev); 676 struct scatterlist sg[2]; 677 u8 promisc, allmulti; 678 struct virtio_net_ctrl_mac *mac_data; 679 struct dev_addr_list *addr; 680 struct netdev_hw_addr *ha; 681 void *buf; 682 int i; 683 684 /* We can't dynamicaly set ndo_set_rx_mode, so return gracefully */ 685 if (!virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_RX)) 686 return; 687 688 promisc = ((dev->flags & IFF_PROMISC) != 0); 689 allmulti = ((dev->flags & IFF_ALLMULTI) != 0); 690 691 sg_init_one(sg, &promisc, sizeof(promisc)); 692 693 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_RX, 694 VIRTIO_NET_CTRL_RX_PROMISC, 695 sg, 1, 0)) 696 dev_warn(&dev->dev, "Failed to %sable promisc mode.\n", 697 promisc ? "en" : "dis"); 698 699 sg_init_one(sg, &allmulti, sizeof(allmulti)); 700 701 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_RX, 702 VIRTIO_NET_CTRL_RX_ALLMULTI, 703 sg, 1, 0)) 704 dev_warn(&dev->dev, "Failed to %sable allmulti mode.\n", 705 allmulti ? "en" : "dis"); 706 707 /* MAC filter - use one buffer for both lists */ 708 mac_data = buf = kzalloc(((dev->uc.count + dev->mc_count) * ETH_ALEN) + 709 (2 * sizeof(mac_data->entries)), GFP_ATOMIC); 710 if (!buf) { 711 dev_warn(&dev->dev, "No memory for MAC address buffer\n"); 712 return; 713 } 714 715 sg_init_table(sg, 2); 716 717 /* Store the unicast list and count in the front of the buffer */ 718 mac_data->entries = dev->uc.count; 719 i = 0; 720 list_for_each_entry(ha, &dev->uc.list, list) 721 memcpy(&mac_data->macs[i++][0], ha->addr, ETH_ALEN); 722 723 sg_set_buf(&sg[0], mac_data, 724 sizeof(mac_data->entries) + (dev->uc.count * ETH_ALEN)); 725 726 /* multicast list and count fill the end */ 727 mac_data = (void *)&mac_data->macs[dev->uc.count][0]; 728 729 mac_data->entries = dev->mc_count; 730 addr = dev->mc_list; 731 for (i = 0; i < dev->mc_count; i++, addr = addr->next) 732 memcpy(&mac_data->macs[i][0], addr->da_addr, ETH_ALEN); 733 734 sg_set_buf(&sg[1], mac_data, 735 sizeof(mac_data->entries) + (dev->mc_count * ETH_ALEN)); 736 737 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_MAC, 738 VIRTIO_NET_CTRL_MAC_TABLE_SET, 739 sg, 2, 0)) 740 dev_warn(&dev->dev, "Failed to set MAC fitler table.\n"); 741 742 kfree(buf); 743 } 744 745 static void virtnet_vlan_rx_add_vid(struct net_device *dev, u16 vid) 746 { 747 struct virtnet_info *vi = netdev_priv(dev); 748 struct scatterlist sg; 749 750 sg_init_one(&sg, &vid, sizeof(vid)); 751 752 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_VLAN, 753 VIRTIO_NET_CTRL_VLAN_ADD, &sg, 1, 0)) 754 dev_warn(&dev->dev, "Failed to add VLAN ID %d.\n", vid); 755 } 756 757 static void virtnet_vlan_rx_kill_vid(struct net_device *dev, u16 vid) 758 { 759 struct virtnet_info *vi = netdev_priv(dev); 760 struct scatterlist sg; 761 762 sg_init_one(&sg, &vid, sizeof(vid)); 763 764 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_VLAN, 765 VIRTIO_NET_CTRL_VLAN_DEL, &sg, 1, 0)) 766 dev_warn(&dev->dev, "Failed to kill VLAN ID %d.\n", vid); 767 } 768 769 static const struct ethtool_ops virtnet_ethtool_ops = { 770 .set_tx_csum = virtnet_set_tx_csum, 771 .set_sg = ethtool_op_set_sg, 772 .set_tso = ethtool_op_set_tso, 773 .set_ufo = ethtool_op_set_ufo, 774 .get_link = ethtool_op_get_link, 775 }; 776 777 #define MIN_MTU 68 778 #define MAX_MTU 65535 779 780 static int virtnet_change_mtu(struct net_device *dev, int new_mtu) 781 { 782 if (new_mtu < MIN_MTU || new_mtu > MAX_MTU) 783 return -EINVAL; 784 dev->mtu = new_mtu; 785 return 0; 786 } 787 788 static const struct net_device_ops virtnet_netdev = { 789 .ndo_open = virtnet_open, 790 .ndo_stop = virtnet_close, 791 .ndo_start_xmit = start_xmit, 792 .ndo_validate_addr = eth_validate_addr, 793 .ndo_set_mac_address = virtnet_set_mac_address, 794 .ndo_set_rx_mode = virtnet_set_rx_mode, 795 .ndo_change_mtu = virtnet_change_mtu, 796 .ndo_vlan_rx_add_vid = virtnet_vlan_rx_add_vid, 797 .ndo_vlan_rx_kill_vid = virtnet_vlan_rx_kill_vid, 798 #ifdef CONFIG_NET_POLL_CONTROLLER 799 .ndo_poll_controller = virtnet_netpoll, 800 #endif 801 }; 802 803 static void virtnet_update_status(struct virtnet_info *vi) 804 { 805 u16 v; 806 807 if (!virtio_has_feature(vi->vdev, VIRTIO_NET_F_STATUS)) 808 return; 809 810 vi->vdev->config->get(vi->vdev, 811 offsetof(struct virtio_net_config, status), 812 &v, sizeof(v)); 813 814 /* Ignore unknown (future) status bits */ 815 v &= VIRTIO_NET_S_LINK_UP; 816 817 if (vi->status == v) 818 return; 819 820 vi->status = v; 821 822 if (vi->status & VIRTIO_NET_S_LINK_UP) { 823 netif_carrier_on(vi->dev); 824 netif_wake_queue(vi->dev); 825 } else { 826 netif_carrier_off(vi->dev); 827 netif_stop_queue(vi->dev); 828 } 829 } 830 831 static void virtnet_config_changed(struct virtio_device *vdev) 832 { 833 struct virtnet_info *vi = vdev->priv; 834 835 virtnet_update_status(vi); 836 } 837 838 static int virtnet_probe(struct virtio_device *vdev) 839 { 840 int err; 841 struct net_device *dev; 842 struct virtnet_info *vi; 843 struct virtqueue *vqs[3]; 844 vq_callback_t *callbacks[] = { skb_recv_done, skb_xmit_done, NULL}; 845 const char *names[] = { "input", "output", "control" }; 846 int nvqs; 847 848 /* Allocate ourselves a network device with room for our info */ 849 dev = alloc_etherdev(sizeof(struct virtnet_info)); 850 if (!dev) 851 return -ENOMEM; 852 853 /* Set up network device as normal. */ 854 dev->netdev_ops = &virtnet_netdev; 855 dev->features = NETIF_F_HIGHDMA; 856 SET_ETHTOOL_OPS(dev, &virtnet_ethtool_ops); 857 SET_NETDEV_DEV(dev, &vdev->dev); 858 859 /* Do we support "hardware" checksums? */ 860 if (csum && virtio_has_feature(vdev, VIRTIO_NET_F_CSUM)) { 861 /* This opens up the world of extra features. */ 862 dev->features |= NETIF_F_HW_CSUM|NETIF_F_SG|NETIF_F_FRAGLIST; 863 if (gso && virtio_has_feature(vdev, VIRTIO_NET_F_GSO)) { 864 dev->features |= NETIF_F_TSO | NETIF_F_UFO 865 | NETIF_F_TSO_ECN | NETIF_F_TSO6; 866 } 867 /* Individual feature bits: what can host handle? */ 868 if (gso && virtio_has_feature(vdev, VIRTIO_NET_F_HOST_TSO4)) 869 dev->features |= NETIF_F_TSO; 870 if (gso && virtio_has_feature(vdev, VIRTIO_NET_F_HOST_TSO6)) 871 dev->features |= NETIF_F_TSO6; 872 if (gso && virtio_has_feature(vdev, VIRTIO_NET_F_HOST_ECN)) 873 dev->features |= NETIF_F_TSO_ECN; 874 if (gso && virtio_has_feature(vdev, VIRTIO_NET_F_HOST_UFO)) 875 dev->features |= NETIF_F_UFO; 876 } 877 878 /* Configuration may specify what MAC to use. Otherwise random. */ 879 if (virtio_has_feature(vdev, VIRTIO_NET_F_MAC)) { 880 vdev->config->get(vdev, 881 offsetof(struct virtio_net_config, mac), 882 dev->dev_addr, dev->addr_len); 883 } else 884 random_ether_addr(dev->dev_addr); 885 886 /* Set up our device-specific information */ 887 vi = netdev_priv(dev); 888 netif_napi_add(dev, &vi->napi, virtnet_poll, napi_weight); 889 vi->dev = dev; 890 vi->vdev = vdev; 891 vdev->priv = vi; 892 vi->pages = NULL; 893 INIT_DELAYED_WORK(&vi->refill, refill_work); 894 895 /* If we can receive ANY GSO packets, we must allocate large ones. */ 896 if (virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_TSO4) 897 || virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_TSO6) 898 || virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_ECN)) 899 vi->big_packets = true; 900 901 if (virtio_has_feature(vdev, VIRTIO_NET_F_MRG_RXBUF)) 902 vi->mergeable_rx_bufs = true; 903 904 /* We expect two virtqueues, receive then send, 905 * and optionally control. */ 906 nvqs = virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ) ? 3 : 2; 907 908 err = vdev->config->find_vqs(vdev, nvqs, vqs, callbacks, names); 909 if (err) 910 goto free; 911 912 vi->rvq = vqs[0]; 913 vi->svq = vqs[1]; 914 915 if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ)) { 916 vi->cvq = vqs[2]; 917 918 if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VLAN)) 919 dev->features |= NETIF_F_HW_VLAN_FILTER; 920 } 921 922 /* Initialize our empty receive and send queues. */ 923 skb_queue_head_init(&vi->recv); 924 skb_queue_head_init(&vi->send); 925 926 err = register_netdev(dev); 927 if (err) { 928 pr_debug("virtio_net: registering device failed\n"); 929 goto free_vqs; 930 } 931 932 /* Last of all, set up some receive buffers. */ 933 try_fill_recv(vi, GFP_KERNEL); 934 935 /* If we didn't even get one input buffer, we're useless. */ 936 if (vi->num == 0) { 937 err = -ENOMEM; 938 goto unregister; 939 } 940 941 vi->status = VIRTIO_NET_S_LINK_UP; 942 virtnet_update_status(vi); 943 netif_carrier_on(dev); 944 945 pr_debug("virtnet: registered device %s\n", dev->name); 946 return 0; 947 948 unregister: 949 unregister_netdev(dev); 950 cancel_delayed_work_sync(&vi->refill); 951 free_vqs: 952 vdev->config->del_vqs(vdev); 953 free: 954 free_netdev(dev); 955 return err; 956 } 957 958 static void __devexit virtnet_remove(struct virtio_device *vdev) 959 { 960 struct virtnet_info *vi = vdev->priv; 961 struct sk_buff *skb; 962 963 /* Stop all the virtqueues. */ 964 vdev->config->reset(vdev); 965 966 /* Free our skbs in send and recv queues, if any. */ 967 while ((skb = __skb_dequeue(&vi->recv)) != NULL) { 968 kfree_skb(skb); 969 vi->num--; 970 } 971 __skb_queue_purge(&vi->send); 972 973 BUG_ON(vi->num != 0); 974 975 unregister_netdev(vi->dev); 976 cancel_delayed_work_sync(&vi->refill); 977 978 vdev->config->del_vqs(vi->vdev); 979 980 while (vi->pages) 981 __free_pages(get_a_page(vi, GFP_KERNEL), 0); 982 983 free_netdev(vi->dev); 984 } 985 986 static struct virtio_device_id id_table[] = { 987 { VIRTIO_ID_NET, VIRTIO_DEV_ANY_ID }, 988 { 0 }, 989 }; 990 991 static unsigned int features[] = { 992 VIRTIO_NET_F_CSUM, VIRTIO_NET_F_GUEST_CSUM, 993 VIRTIO_NET_F_GSO, VIRTIO_NET_F_MAC, 994 VIRTIO_NET_F_HOST_TSO4, VIRTIO_NET_F_HOST_UFO, VIRTIO_NET_F_HOST_TSO6, 995 VIRTIO_NET_F_HOST_ECN, VIRTIO_NET_F_GUEST_TSO4, VIRTIO_NET_F_GUEST_TSO6, 996 VIRTIO_NET_F_GUEST_ECN, VIRTIO_NET_F_GUEST_UFO, 997 VIRTIO_NET_F_MRG_RXBUF, VIRTIO_NET_F_STATUS, VIRTIO_NET_F_CTRL_VQ, 998 VIRTIO_NET_F_CTRL_RX, VIRTIO_NET_F_CTRL_VLAN, 999 }; 1000 1001 static struct virtio_driver virtio_net_driver = { 1002 .feature_table = features, 1003 .feature_table_size = ARRAY_SIZE(features), 1004 .driver.name = KBUILD_MODNAME, 1005 .driver.owner = THIS_MODULE, 1006 .id_table = id_table, 1007 .probe = virtnet_probe, 1008 .remove = __devexit_p(virtnet_remove), 1009 .config_changed = virtnet_config_changed, 1010 }; 1011 1012 static int __init init(void) 1013 { 1014 return register_virtio_driver(&virtio_net_driver); 1015 } 1016 1017 static void __exit fini(void) 1018 { 1019 unregister_virtio_driver(&virtio_net_driver); 1020 } 1021 module_init(init); 1022 module_exit(fini); 1023 1024 MODULE_DEVICE_TABLE(virtio, id_table); 1025 MODULE_DESCRIPTION("Virtio network driver"); 1026 MODULE_LICENSE("GPL"); 1027