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, see <http://www.gnu.org/licenses/>. 17 */ 18 //#define DEBUG 19 #include <linux/netdevice.h> 20 #include <linux/etherdevice.h> 21 #include <linux/ethtool.h> 22 #include <linux/module.h> 23 #include <linux/virtio.h> 24 #include <linux/virtio_net.h> 25 #include <linux/scatterlist.h> 26 #include <linux/if_vlan.h> 27 #include <linux/slab.h> 28 #include <linux/cpu.h> 29 #include <linux/average.h> 30 #include <net/busy_poll.h> 31 32 static int napi_weight = NAPI_POLL_WEIGHT; 33 module_param(napi_weight, int, 0444); 34 35 static bool csum = true, gso = true; 36 module_param(csum, bool, 0444); 37 module_param(gso, bool, 0444); 38 39 /* FIXME: MTU in config. */ 40 #define GOOD_PACKET_LEN (ETH_HLEN + VLAN_HLEN + ETH_DATA_LEN) 41 #define GOOD_COPY_LEN 128 42 43 /* RX packet size EWMA. The average packet size is used to determine the packet 44 * buffer size when refilling RX rings. As the entire RX ring may be refilled 45 * at once, the weight is chosen so that the EWMA will be insensitive to short- 46 * term, transient changes in packet size. 47 */ 48 DECLARE_EWMA(pkt_len, 1, 64) 49 50 /* Minimum alignment for mergeable packet buffers. */ 51 #define MERGEABLE_BUFFER_ALIGN max(L1_CACHE_BYTES, 256) 52 53 #define VIRTNET_DRIVER_VERSION "1.0.0" 54 55 struct virtnet_stats { 56 struct u64_stats_sync tx_syncp; 57 struct u64_stats_sync rx_syncp; 58 u64 tx_bytes; 59 u64 tx_packets; 60 61 u64 rx_bytes; 62 u64 rx_packets; 63 }; 64 65 /* Internal representation of a send virtqueue */ 66 struct send_queue { 67 /* Virtqueue associated with this send _queue */ 68 struct virtqueue *vq; 69 70 /* TX: fragments + linear part + virtio header */ 71 struct scatterlist sg[MAX_SKB_FRAGS + 2]; 72 73 /* Name of the send queue: output.$index */ 74 char name[40]; 75 }; 76 77 /* Internal representation of a receive virtqueue */ 78 struct receive_queue { 79 /* Virtqueue associated with this receive_queue */ 80 struct virtqueue *vq; 81 82 struct napi_struct napi; 83 84 /* Chain pages by the private ptr. */ 85 struct page *pages; 86 87 /* Average packet length for mergeable receive buffers. */ 88 struct ewma_pkt_len mrg_avg_pkt_len; 89 90 /* Page frag for packet buffer allocation. */ 91 struct page_frag alloc_frag; 92 93 /* RX: fragments + linear part + virtio header */ 94 struct scatterlist sg[MAX_SKB_FRAGS + 2]; 95 96 /* Name of this receive queue: input.$index */ 97 char name[40]; 98 }; 99 100 struct virtnet_info { 101 struct virtio_device *vdev; 102 struct virtqueue *cvq; 103 struct net_device *dev; 104 struct send_queue *sq; 105 struct receive_queue *rq; 106 unsigned int status; 107 108 /* Max # of queue pairs supported by the device */ 109 u16 max_queue_pairs; 110 111 /* # of queue pairs currently used by the driver */ 112 u16 curr_queue_pairs; 113 114 /* I like... big packets and I cannot lie! */ 115 bool big_packets; 116 117 /* Host will merge rx buffers for big packets (shake it! shake it!) */ 118 bool mergeable_rx_bufs; 119 120 /* Has control virtqueue */ 121 bool has_cvq; 122 123 /* Host can handle any s/g split between our header and packet data */ 124 bool any_header_sg; 125 126 /* Packet virtio header size */ 127 u8 hdr_len; 128 129 /* Active statistics */ 130 struct virtnet_stats __percpu *stats; 131 132 /* Work struct for refilling if we run low on memory. */ 133 struct delayed_work refill; 134 135 /* Work struct for config space updates */ 136 struct work_struct config_work; 137 138 /* Does the affinity hint is set for virtqueues? */ 139 bool affinity_hint_set; 140 141 /* CPU hotplug instances for online & dead */ 142 struct hlist_node node; 143 struct hlist_node node_dead; 144 145 /* Control VQ buffers: protected by the rtnl lock */ 146 struct virtio_net_ctrl_hdr ctrl_hdr; 147 virtio_net_ctrl_ack ctrl_status; 148 struct virtio_net_ctrl_mq ctrl_mq; 149 u8 ctrl_promisc; 150 u8 ctrl_allmulti; 151 u16 ctrl_vid; 152 153 /* Ethtool settings */ 154 u8 duplex; 155 u32 speed; 156 }; 157 158 struct padded_vnet_hdr { 159 struct virtio_net_hdr_mrg_rxbuf hdr; 160 /* 161 * hdr is in a separate sg buffer, and data sg buffer shares same page 162 * with this header sg. This padding makes next sg 16 byte aligned 163 * after the header. 164 */ 165 char padding[4]; 166 }; 167 168 /* Converting between virtqueue no. and kernel tx/rx queue no. 169 * 0:rx0 1:tx0 2:rx1 3:tx1 ... 2N:rxN 2N+1:txN 2N+2:cvq 170 */ 171 static int vq2txq(struct virtqueue *vq) 172 { 173 return (vq->index - 1) / 2; 174 } 175 176 static int txq2vq(int txq) 177 { 178 return txq * 2 + 1; 179 } 180 181 static int vq2rxq(struct virtqueue *vq) 182 { 183 return vq->index / 2; 184 } 185 186 static int rxq2vq(int rxq) 187 { 188 return rxq * 2; 189 } 190 191 static inline struct virtio_net_hdr_mrg_rxbuf *skb_vnet_hdr(struct sk_buff *skb) 192 { 193 return (struct virtio_net_hdr_mrg_rxbuf *)skb->cb; 194 } 195 196 /* 197 * private is used to chain pages for big packets, put the whole 198 * most recent used list in the beginning for reuse 199 */ 200 static void give_pages(struct receive_queue *rq, struct page *page) 201 { 202 struct page *end; 203 204 /* Find end of list, sew whole thing into vi->rq.pages. */ 205 for (end = page; end->private; end = (struct page *)end->private); 206 end->private = (unsigned long)rq->pages; 207 rq->pages = page; 208 } 209 210 static struct page *get_a_page(struct receive_queue *rq, gfp_t gfp_mask) 211 { 212 struct page *p = rq->pages; 213 214 if (p) { 215 rq->pages = (struct page *)p->private; 216 /* clear private here, it is used to chain pages */ 217 p->private = 0; 218 } else 219 p = alloc_page(gfp_mask); 220 return p; 221 } 222 223 static void skb_xmit_done(struct virtqueue *vq) 224 { 225 struct virtnet_info *vi = vq->vdev->priv; 226 227 /* Suppress further interrupts. */ 228 virtqueue_disable_cb(vq); 229 230 /* We were probably waiting for more output buffers. */ 231 netif_wake_subqueue(vi->dev, vq2txq(vq)); 232 } 233 234 static unsigned int mergeable_ctx_to_buf_truesize(unsigned long mrg_ctx) 235 { 236 unsigned int truesize = mrg_ctx & (MERGEABLE_BUFFER_ALIGN - 1); 237 return (truesize + 1) * MERGEABLE_BUFFER_ALIGN; 238 } 239 240 static void *mergeable_ctx_to_buf_address(unsigned long mrg_ctx) 241 { 242 return (void *)(mrg_ctx & -MERGEABLE_BUFFER_ALIGN); 243 244 } 245 246 static unsigned long mergeable_buf_to_ctx(void *buf, unsigned int truesize) 247 { 248 unsigned int size = truesize / MERGEABLE_BUFFER_ALIGN; 249 return (unsigned long)buf | (size - 1); 250 } 251 252 /* Called from bottom half context */ 253 static struct sk_buff *page_to_skb(struct virtnet_info *vi, 254 struct receive_queue *rq, 255 struct page *page, unsigned int offset, 256 unsigned int len, unsigned int truesize) 257 { 258 struct sk_buff *skb; 259 struct virtio_net_hdr_mrg_rxbuf *hdr; 260 unsigned int copy, hdr_len, hdr_padded_len; 261 char *p; 262 263 p = page_address(page) + offset; 264 265 /* copy small packet so we can reuse these pages for small data */ 266 skb = napi_alloc_skb(&rq->napi, GOOD_COPY_LEN); 267 if (unlikely(!skb)) 268 return NULL; 269 270 hdr = skb_vnet_hdr(skb); 271 272 hdr_len = vi->hdr_len; 273 if (vi->mergeable_rx_bufs) 274 hdr_padded_len = sizeof *hdr; 275 else 276 hdr_padded_len = sizeof(struct padded_vnet_hdr); 277 278 memcpy(hdr, p, hdr_len); 279 280 len -= hdr_len; 281 offset += hdr_padded_len; 282 p += hdr_padded_len; 283 284 copy = len; 285 if (copy > skb_tailroom(skb)) 286 copy = skb_tailroom(skb); 287 memcpy(skb_put(skb, copy), p, copy); 288 289 len -= copy; 290 offset += copy; 291 292 if (vi->mergeable_rx_bufs) { 293 if (len) 294 skb_add_rx_frag(skb, 0, page, offset, len, truesize); 295 else 296 put_page(page); 297 return skb; 298 } 299 300 /* 301 * Verify that we can indeed put this data into a skb. 302 * This is here to handle cases when the device erroneously 303 * tries to receive more than is possible. This is usually 304 * the case of a broken device. 305 */ 306 if (unlikely(len > MAX_SKB_FRAGS * PAGE_SIZE)) { 307 net_dbg_ratelimited("%s: too much data\n", skb->dev->name); 308 dev_kfree_skb(skb); 309 return NULL; 310 } 311 BUG_ON(offset >= PAGE_SIZE); 312 while (len) { 313 unsigned int frag_size = min((unsigned)PAGE_SIZE - offset, len); 314 skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags, page, offset, 315 frag_size, truesize); 316 len -= frag_size; 317 page = (struct page *)page->private; 318 offset = 0; 319 } 320 321 if (page) 322 give_pages(rq, page); 323 324 return skb; 325 } 326 327 static struct sk_buff *receive_small(struct virtnet_info *vi, void *buf, unsigned int len) 328 { 329 struct sk_buff * skb = buf; 330 331 len -= vi->hdr_len; 332 skb_trim(skb, len); 333 334 return skb; 335 } 336 337 static struct sk_buff *receive_big(struct net_device *dev, 338 struct virtnet_info *vi, 339 struct receive_queue *rq, 340 void *buf, 341 unsigned int len) 342 { 343 struct page *page = buf; 344 struct sk_buff *skb = page_to_skb(vi, rq, page, 0, len, PAGE_SIZE); 345 346 if (unlikely(!skb)) 347 goto err; 348 349 return skb; 350 351 err: 352 dev->stats.rx_dropped++; 353 give_pages(rq, page); 354 return NULL; 355 } 356 357 static struct sk_buff *receive_mergeable(struct net_device *dev, 358 struct virtnet_info *vi, 359 struct receive_queue *rq, 360 unsigned long ctx, 361 unsigned int len) 362 { 363 void *buf = mergeable_ctx_to_buf_address(ctx); 364 struct virtio_net_hdr_mrg_rxbuf *hdr = buf; 365 u16 num_buf = virtio16_to_cpu(vi->vdev, hdr->num_buffers); 366 struct page *page = virt_to_head_page(buf); 367 int offset = buf - page_address(page); 368 unsigned int truesize = max(len, mergeable_ctx_to_buf_truesize(ctx)); 369 370 struct sk_buff *head_skb = page_to_skb(vi, rq, page, offset, len, 371 truesize); 372 struct sk_buff *curr_skb = head_skb; 373 374 if (unlikely(!curr_skb)) 375 goto err_skb; 376 while (--num_buf) { 377 int num_skb_frags; 378 379 ctx = (unsigned long)virtqueue_get_buf(rq->vq, &len); 380 if (unlikely(!ctx)) { 381 pr_debug("%s: rx error: %d buffers out of %d missing\n", 382 dev->name, num_buf, 383 virtio16_to_cpu(vi->vdev, 384 hdr->num_buffers)); 385 dev->stats.rx_length_errors++; 386 goto err_buf; 387 } 388 389 buf = mergeable_ctx_to_buf_address(ctx); 390 page = virt_to_head_page(buf); 391 392 num_skb_frags = skb_shinfo(curr_skb)->nr_frags; 393 if (unlikely(num_skb_frags == MAX_SKB_FRAGS)) { 394 struct sk_buff *nskb = alloc_skb(0, GFP_ATOMIC); 395 396 if (unlikely(!nskb)) 397 goto err_skb; 398 if (curr_skb == head_skb) 399 skb_shinfo(curr_skb)->frag_list = nskb; 400 else 401 curr_skb->next = nskb; 402 curr_skb = nskb; 403 head_skb->truesize += nskb->truesize; 404 num_skb_frags = 0; 405 } 406 truesize = max(len, mergeable_ctx_to_buf_truesize(ctx)); 407 if (curr_skb != head_skb) { 408 head_skb->data_len += len; 409 head_skb->len += len; 410 head_skb->truesize += truesize; 411 } 412 offset = buf - page_address(page); 413 if (skb_can_coalesce(curr_skb, num_skb_frags, page, offset)) { 414 put_page(page); 415 skb_coalesce_rx_frag(curr_skb, num_skb_frags - 1, 416 len, truesize); 417 } else { 418 skb_add_rx_frag(curr_skb, num_skb_frags, page, 419 offset, len, truesize); 420 } 421 } 422 423 ewma_pkt_len_add(&rq->mrg_avg_pkt_len, head_skb->len); 424 return head_skb; 425 426 err_skb: 427 put_page(page); 428 while (--num_buf) { 429 ctx = (unsigned long)virtqueue_get_buf(rq->vq, &len); 430 if (unlikely(!ctx)) { 431 pr_debug("%s: rx error: %d buffers missing\n", 432 dev->name, num_buf); 433 dev->stats.rx_length_errors++; 434 break; 435 } 436 page = virt_to_head_page(mergeable_ctx_to_buf_address(ctx)); 437 put_page(page); 438 } 439 err_buf: 440 dev->stats.rx_dropped++; 441 dev_kfree_skb(head_skb); 442 return NULL; 443 } 444 445 static void receive_buf(struct virtnet_info *vi, struct receive_queue *rq, 446 void *buf, unsigned int len) 447 { 448 struct net_device *dev = vi->dev; 449 struct virtnet_stats *stats = this_cpu_ptr(vi->stats); 450 struct sk_buff *skb; 451 struct virtio_net_hdr_mrg_rxbuf *hdr; 452 453 if (unlikely(len < vi->hdr_len + ETH_HLEN)) { 454 pr_debug("%s: short packet %i\n", dev->name, len); 455 dev->stats.rx_length_errors++; 456 if (vi->mergeable_rx_bufs) { 457 unsigned long ctx = (unsigned long)buf; 458 void *base = mergeable_ctx_to_buf_address(ctx); 459 put_page(virt_to_head_page(base)); 460 } else if (vi->big_packets) { 461 give_pages(rq, buf); 462 } else { 463 dev_kfree_skb(buf); 464 } 465 return; 466 } 467 468 if (vi->mergeable_rx_bufs) 469 skb = receive_mergeable(dev, vi, rq, (unsigned long)buf, len); 470 else if (vi->big_packets) 471 skb = receive_big(dev, vi, rq, buf, len); 472 else 473 skb = receive_small(vi, buf, len); 474 475 if (unlikely(!skb)) 476 return; 477 478 hdr = skb_vnet_hdr(skb); 479 480 u64_stats_update_begin(&stats->rx_syncp); 481 stats->rx_bytes += skb->len; 482 stats->rx_packets++; 483 u64_stats_update_end(&stats->rx_syncp); 484 485 if (hdr->hdr.flags & VIRTIO_NET_HDR_F_DATA_VALID) 486 skb->ip_summed = CHECKSUM_UNNECESSARY; 487 488 if (virtio_net_hdr_to_skb(skb, &hdr->hdr, 489 virtio_is_little_endian(vi->vdev))) { 490 net_warn_ratelimited("%s: bad gso: type: %u, size: %u\n", 491 dev->name, hdr->hdr.gso_type, 492 hdr->hdr.gso_size); 493 goto frame_err; 494 } 495 496 skb->protocol = eth_type_trans(skb, dev); 497 pr_debug("Receiving skb proto 0x%04x len %i type %i\n", 498 ntohs(skb->protocol), skb->len, skb->pkt_type); 499 500 napi_gro_receive(&rq->napi, skb); 501 return; 502 503 frame_err: 504 dev->stats.rx_frame_errors++; 505 dev_kfree_skb(skb); 506 } 507 508 static int add_recvbuf_small(struct virtnet_info *vi, struct receive_queue *rq, 509 gfp_t gfp) 510 { 511 struct sk_buff *skb; 512 struct virtio_net_hdr_mrg_rxbuf *hdr; 513 int err; 514 515 skb = __netdev_alloc_skb_ip_align(vi->dev, GOOD_PACKET_LEN, gfp); 516 if (unlikely(!skb)) 517 return -ENOMEM; 518 519 skb_put(skb, GOOD_PACKET_LEN); 520 521 hdr = skb_vnet_hdr(skb); 522 sg_init_table(rq->sg, 2); 523 sg_set_buf(rq->sg, hdr, vi->hdr_len); 524 skb_to_sgvec(skb, rq->sg + 1, 0, skb->len); 525 526 err = virtqueue_add_inbuf(rq->vq, rq->sg, 2, skb, gfp); 527 if (err < 0) 528 dev_kfree_skb(skb); 529 530 return err; 531 } 532 533 static int add_recvbuf_big(struct virtnet_info *vi, struct receive_queue *rq, 534 gfp_t gfp) 535 { 536 struct page *first, *list = NULL; 537 char *p; 538 int i, err, offset; 539 540 sg_init_table(rq->sg, MAX_SKB_FRAGS + 2); 541 542 /* page in rq->sg[MAX_SKB_FRAGS + 1] is list tail */ 543 for (i = MAX_SKB_FRAGS + 1; i > 1; --i) { 544 first = get_a_page(rq, gfp); 545 if (!first) { 546 if (list) 547 give_pages(rq, list); 548 return -ENOMEM; 549 } 550 sg_set_buf(&rq->sg[i], page_address(first), PAGE_SIZE); 551 552 /* chain new page in list head to match sg */ 553 first->private = (unsigned long)list; 554 list = first; 555 } 556 557 first = get_a_page(rq, gfp); 558 if (!first) { 559 give_pages(rq, list); 560 return -ENOMEM; 561 } 562 p = page_address(first); 563 564 /* rq->sg[0], rq->sg[1] share the same page */ 565 /* a separated rq->sg[0] for header - required in case !any_header_sg */ 566 sg_set_buf(&rq->sg[0], p, vi->hdr_len); 567 568 /* rq->sg[1] for data packet, from offset */ 569 offset = sizeof(struct padded_vnet_hdr); 570 sg_set_buf(&rq->sg[1], p + offset, PAGE_SIZE - offset); 571 572 /* chain first in list head */ 573 first->private = (unsigned long)list; 574 err = virtqueue_add_inbuf(rq->vq, rq->sg, MAX_SKB_FRAGS + 2, 575 first, gfp); 576 if (err < 0) 577 give_pages(rq, first); 578 579 return err; 580 } 581 582 static unsigned int get_mergeable_buf_len(struct ewma_pkt_len *avg_pkt_len) 583 { 584 const size_t hdr_len = sizeof(struct virtio_net_hdr_mrg_rxbuf); 585 unsigned int len; 586 587 len = hdr_len + clamp_t(unsigned int, ewma_pkt_len_read(avg_pkt_len), 588 GOOD_PACKET_LEN, PAGE_SIZE - hdr_len); 589 return ALIGN(len, MERGEABLE_BUFFER_ALIGN); 590 } 591 592 static int add_recvbuf_mergeable(struct receive_queue *rq, gfp_t gfp) 593 { 594 struct page_frag *alloc_frag = &rq->alloc_frag; 595 char *buf; 596 unsigned long ctx; 597 int err; 598 unsigned int len, hole; 599 600 len = get_mergeable_buf_len(&rq->mrg_avg_pkt_len); 601 if (unlikely(!skb_page_frag_refill(len, alloc_frag, gfp))) 602 return -ENOMEM; 603 604 buf = (char *)page_address(alloc_frag->page) + alloc_frag->offset; 605 ctx = mergeable_buf_to_ctx(buf, len); 606 get_page(alloc_frag->page); 607 alloc_frag->offset += len; 608 hole = alloc_frag->size - alloc_frag->offset; 609 if (hole < len) { 610 /* To avoid internal fragmentation, if there is very likely not 611 * enough space for another buffer, add the remaining space to 612 * the current buffer. This extra space is not included in 613 * the truesize stored in ctx. 614 */ 615 len += hole; 616 alloc_frag->offset += hole; 617 } 618 619 sg_init_one(rq->sg, buf, len); 620 err = virtqueue_add_inbuf(rq->vq, rq->sg, 1, (void *)ctx, gfp); 621 if (err < 0) 622 put_page(virt_to_head_page(buf)); 623 624 return err; 625 } 626 627 /* 628 * Returns false if we couldn't fill entirely (OOM). 629 * 630 * Normally run in the receive path, but can also be run from ndo_open 631 * before we're receiving packets, or from refill_work which is 632 * careful to disable receiving (using napi_disable). 633 */ 634 static bool try_fill_recv(struct virtnet_info *vi, struct receive_queue *rq, 635 gfp_t gfp) 636 { 637 int err; 638 bool oom; 639 640 gfp |= __GFP_COLD; 641 do { 642 if (vi->mergeable_rx_bufs) 643 err = add_recvbuf_mergeable(rq, gfp); 644 else if (vi->big_packets) 645 err = add_recvbuf_big(vi, rq, gfp); 646 else 647 err = add_recvbuf_small(vi, rq, gfp); 648 649 oom = err == -ENOMEM; 650 if (err) 651 break; 652 } while (rq->vq->num_free); 653 virtqueue_kick(rq->vq); 654 return !oom; 655 } 656 657 static void skb_recv_done(struct virtqueue *rvq) 658 { 659 struct virtnet_info *vi = rvq->vdev->priv; 660 struct receive_queue *rq = &vi->rq[vq2rxq(rvq)]; 661 662 /* Schedule NAPI, Suppress further interrupts if successful. */ 663 if (napi_schedule_prep(&rq->napi)) { 664 virtqueue_disable_cb(rvq); 665 __napi_schedule(&rq->napi); 666 } 667 } 668 669 static void virtnet_napi_enable(struct receive_queue *rq) 670 { 671 napi_enable(&rq->napi); 672 673 /* If all buffers were filled by other side before we napi_enabled, we 674 * won't get another interrupt, so process any outstanding packets 675 * now. virtnet_poll wants re-enable the queue, so we disable here. 676 * We synchronize against interrupts via NAPI_STATE_SCHED */ 677 if (napi_schedule_prep(&rq->napi)) { 678 virtqueue_disable_cb(rq->vq); 679 local_bh_disable(); 680 __napi_schedule(&rq->napi); 681 local_bh_enable(); 682 } 683 } 684 685 static void refill_work(struct work_struct *work) 686 { 687 struct virtnet_info *vi = 688 container_of(work, struct virtnet_info, refill.work); 689 bool still_empty; 690 int i; 691 692 for (i = 0; i < vi->curr_queue_pairs; i++) { 693 struct receive_queue *rq = &vi->rq[i]; 694 695 napi_disable(&rq->napi); 696 still_empty = !try_fill_recv(vi, rq, GFP_KERNEL); 697 virtnet_napi_enable(rq); 698 699 /* In theory, this can happen: if we don't get any buffers in 700 * we will *never* try to fill again. 701 */ 702 if (still_empty) 703 schedule_delayed_work(&vi->refill, HZ/2); 704 } 705 } 706 707 static int virtnet_receive(struct receive_queue *rq, int budget) 708 { 709 struct virtnet_info *vi = rq->vq->vdev->priv; 710 unsigned int len, received = 0; 711 void *buf; 712 713 while (received < budget && 714 (buf = virtqueue_get_buf(rq->vq, &len)) != NULL) { 715 receive_buf(vi, rq, buf, len); 716 received++; 717 } 718 719 if (rq->vq->num_free > virtqueue_get_vring_size(rq->vq) / 2) { 720 if (!try_fill_recv(vi, rq, GFP_ATOMIC)) 721 schedule_delayed_work(&vi->refill, 0); 722 } 723 724 return received; 725 } 726 727 static int virtnet_poll(struct napi_struct *napi, int budget) 728 { 729 struct receive_queue *rq = 730 container_of(napi, struct receive_queue, napi); 731 unsigned int r, received; 732 733 received = virtnet_receive(rq, budget); 734 735 /* Out of packets? */ 736 if (received < budget) { 737 r = virtqueue_enable_cb_prepare(rq->vq); 738 napi_complete_done(napi, received); 739 if (unlikely(virtqueue_poll(rq->vq, r)) && 740 napi_schedule_prep(napi)) { 741 virtqueue_disable_cb(rq->vq); 742 __napi_schedule(napi); 743 } 744 } 745 746 return received; 747 } 748 749 #ifdef CONFIG_NET_RX_BUSY_POLL 750 /* must be called with local_bh_disable()d */ 751 static int virtnet_busy_poll(struct napi_struct *napi) 752 { 753 struct receive_queue *rq = 754 container_of(napi, struct receive_queue, napi); 755 struct virtnet_info *vi = rq->vq->vdev->priv; 756 int r, received = 0, budget = 4; 757 758 if (!(vi->status & VIRTIO_NET_S_LINK_UP)) 759 return LL_FLUSH_FAILED; 760 761 if (!napi_schedule_prep(napi)) 762 return LL_FLUSH_BUSY; 763 764 virtqueue_disable_cb(rq->vq); 765 766 again: 767 received += virtnet_receive(rq, budget); 768 769 r = virtqueue_enable_cb_prepare(rq->vq); 770 clear_bit(NAPI_STATE_SCHED, &napi->state); 771 if (unlikely(virtqueue_poll(rq->vq, r)) && 772 napi_schedule_prep(napi)) { 773 virtqueue_disable_cb(rq->vq); 774 if (received < budget) { 775 budget -= received; 776 goto again; 777 } else { 778 __napi_schedule(napi); 779 } 780 } 781 782 return received; 783 } 784 #endif /* CONFIG_NET_RX_BUSY_POLL */ 785 786 static int virtnet_open(struct net_device *dev) 787 { 788 struct virtnet_info *vi = netdev_priv(dev); 789 int i; 790 791 for (i = 0; i < vi->max_queue_pairs; i++) { 792 if (i < vi->curr_queue_pairs) 793 /* Make sure we have some buffers: if oom use wq. */ 794 if (!try_fill_recv(vi, &vi->rq[i], GFP_KERNEL)) 795 schedule_delayed_work(&vi->refill, 0); 796 virtnet_napi_enable(&vi->rq[i]); 797 } 798 799 return 0; 800 } 801 802 static void free_old_xmit_skbs(struct send_queue *sq) 803 { 804 struct sk_buff *skb; 805 unsigned int len; 806 struct virtnet_info *vi = sq->vq->vdev->priv; 807 struct virtnet_stats *stats = this_cpu_ptr(vi->stats); 808 809 while ((skb = virtqueue_get_buf(sq->vq, &len)) != NULL) { 810 pr_debug("Sent skb %p\n", skb); 811 812 u64_stats_update_begin(&stats->tx_syncp); 813 stats->tx_bytes += skb->len; 814 stats->tx_packets++; 815 u64_stats_update_end(&stats->tx_syncp); 816 817 dev_kfree_skb_any(skb); 818 } 819 } 820 821 static int xmit_skb(struct send_queue *sq, struct sk_buff *skb) 822 { 823 struct virtio_net_hdr_mrg_rxbuf *hdr; 824 const unsigned char *dest = ((struct ethhdr *)skb->data)->h_dest; 825 struct virtnet_info *vi = sq->vq->vdev->priv; 826 unsigned num_sg; 827 unsigned hdr_len = vi->hdr_len; 828 bool can_push; 829 830 pr_debug("%s: xmit %p %pM\n", vi->dev->name, skb, dest); 831 832 can_push = vi->any_header_sg && 833 !((unsigned long)skb->data & (__alignof__(*hdr) - 1)) && 834 !skb_header_cloned(skb) && skb_headroom(skb) >= hdr_len; 835 /* Even if we can, don't push here yet as this would skew 836 * csum_start offset below. */ 837 if (can_push) 838 hdr = (struct virtio_net_hdr_mrg_rxbuf *)(skb->data - hdr_len); 839 else 840 hdr = skb_vnet_hdr(skb); 841 842 if (virtio_net_hdr_from_skb(skb, &hdr->hdr, 843 virtio_is_little_endian(vi->vdev))) 844 BUG(); 845 846 if (vi->mergeable_rx_bufs) 847 hdr->num_buffers = 0; 848 849 sg_init_table(sq->sg, skb_shinfo(skb)->nr_frags + (can_push ? 1 : 2)); 850 if (can_push) { 851 __skb_push(skb, hdr_len); 852 num_sg = skb_to_sgvec(skb, sq->sg, 0, skb->len); 853 /* Pull header back to avoid skew in tx bytes calculations. */ 854 __skb_pull(skb, hdr_len); 855 } else { 856 sg_set_buf(sq->sg, hdr, hdr_len); 857 num_sg = skb_to_sgvec(skb, sq->sg + 1, 0, skb->len) + 1; 858 } 859 return virtqueue_add_outbuf(sq->vq, sq->sg, num_sg, skb, GFP_ATOMIC); 860 } 861 862 static netdev_tx_t start_xmit(struct sk_buff *skb, struct net_device *dev) 863 { 864 struct virtnet_info *vi = netdev_priv(dev); 865 int qnum = skb_get_queue_mapping(skb); 866 struct send_queue *sq = &vi->sq[qnum]; 867 int err; 868 struct netdev_queue *txq = netdev_get_tx_queue(dev, qnum); 869 bool kick = !skb->xmit_more; 870 871 /* Free up any pending old buffers before queueing new ones. */ 872 free_old_xmit_skbs(sq); 873 874 /* timestamp packet in software */ 875 skb_tx_timestamp(skb); 876 877 /* Try to transmit */ 878 err = xmit_skb(sq, skb); 879 880 /* This should not happen! */ 881 if (unlikely(err)) { 882 dev->stats.tx_fifo_errors++; 883 if (net_ratelimit()) 884 dev_warn(&dev->dev, 885 "Unexpected TXQ (%d) queue failure: %d\n", qnum, err); 886 dev->stats.tx_dropped++; 887 dev_kfree_skb_any(skb); 888 return NETDEV_TX_OK; 889 } 890 891 /* Don't wait up for transmitted skbs to be freed. */ 892 skb_orphan(skb); 893 nf_reset(skb); 894 895 /* If running out of space, stop queue to avoid getting packets that we 896 * are then unable to transmit. 897 * An alternative would be to force queuing layer to requeue the skb by 898 * returning NETDEV_TX_BUSY. However, NETDEV_TX_BUSY should not be 899 * returned in a normal path of operation: it means that driver is not 900 * maintaining the TX queue stop/start state properly, and causes 901 * the stack to do a non-trivial amount of useless work. 902 * Since most packets only take 1 or 2 ring slots, stopping the queue 903 * early means 16 slots are typically wasted. 904 */ 905 if (sq->vq->num_free < 2+MAX_SKB_FRAGS) { 906 netif_stop_subqueue(dev, qnum); 907 if (unlikely(!virtqueue_enable_cb_delayed(sq->vq))) { 908 /* More just got used, free them then recheck. */ 909 free_old_xmit_skbs(sq); 910 if (sq->vq->num_free >= 2+MAX_SKB_FRAGS) { 911 netif_start_subqueue(dev, qnum); 912 virtqueue_disable_cb(sq->vq); 913 } 914 } 915 } 916 917 if (kick || netif_xmit_stopped(txq)) 918 virtqueue_kick(sq->vq); 919 920 return NETDEV_TX_OK; 921 } 922 923 /* 924 * Send command via the control virtqueue and check status. Commands 925 * supported by the hypervisor, as indicated by feature bits, should 926 * never fail unless improperly formatted. 927 */ 928 static bool virtnet_send_command(struct virtnet_info *vi, u8 class, u8 cmd, 929 struct scatterlist *out) 930 { 931 struct scatterlist *sgs[4], hdr, stat; 932 unsigned out_num = 0, tmp; 933 934 /* Caller should know better */ 935 BUG_ON(!virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ)); 936 937 vi->ctrl_status = ~0; 938 vi->ctrl_hdr.class = class; 939 vi->ctrl_hdr.cmd = cmd; 940 /* Add header */ 941 sg_init_one(&hdr, &vi->ctrl_hdr, sizeof(vi->ctrl_hdr)); 942 sgs[out_num++] = &hdr; 943 944 if (out) 945 sgs[out_num++] = out; 946 947 /* Add return status. */ 948 sg_init_one(&stat, &vi->ctrl_status, sizeof(vi->ctrl_status)); 949 sgs[out_num] = &stat; 950 951 BUG_ON(out_num + 1 > ARRAY_SIZE(sgs)); 952 virtqueue_add_sgs(vi->cvq, sgs, out_num, 1, vi, GFP_ATOMIC); 953 954 if (unlikely(!virtqueue_kick(vi->cvq))) 955 return vi->ctrl_status == VIRTIO_NET_OK; 956 957 /* Spin for a response, the kick causes an ioport write, trapping 958 * into the hypervisor, so the request should be handled immediately. 959 */ 960 while (!virtqueue_get_buf(vi->cvq, &tmp) && 961 !virtqueue_is_broken(vi->cvq)) 962 cpu_relax(); 963 964 return vi->ctrl_status == VIRTIO_NET_OK; 965 } 966 967 static int virtnet_set_mac_address(struct net_device *dev, void *p) 968 { 969 struct virtnet_info *vi = netdev_priv(dev); 970 struct virtio_device *vdev = vi->vdev; 971 int ret; 972 struct sockaddr *addr = p; 973 struct scatterlist sg; 974 975 ret = eth_prepare_mac_addr_change(dev, p); 976 if (ret) 977 return ret; 978 979 if (virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_MAC_ADDR)) { 980 sg_init_one(&sg, addr->sa_data, dev->addr_len); 981 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_MAC, 982 VIRTIO_NET_CTRL_MAC_ADDR_SET, &sg)) { 983 dev_warn(&vdev->dev, 984 "Failed to set mac address by vq command.\n"); 985 return -EINVAL; 986 } 987 } else if (virtio_has_feature(vdev, VIRTIO_NET_F_MAC) && 988 !virtio_has_feature(vdev, VIRTIO_F_VERSION_1)) { 989 unsigned int i; 990 991 /* Naturally, this has an atomicity problem. */ 992 for (i = 0; i < dev->addr_len; i++) 993 virtio_cwrite8(vdev, 994 offsetof(struct virtio_net_config, mac) + 995 i, addr->sa_data[i]); 996 } 997 998 eth_commit_mac_addr_change(dev, p); 999 1000 return 0; 1001 } 1002 1003 static struct rtnl_link_stats64 *virtnet_stats(struct net_device *dev, 1004 struct rtnl_link_stats64 *tot) 1005 { 1006 struct virtnet_info *vi = netdev_priv(dev); 1007 int cpu; 1008 unsigned int start; 1009 1010 for_each_possible_cpu(cpu) { 1011 struct virtnet_stats *stats = per_cpu_ptr(vi->stats, cpu); 1012 u64 tpackets, tbytes, rpackets, rbytes; 1013 1014 do { 1015 start = u64_stats_fetch_begin_irq(&stats->tx_syncp); 1016 tpackets = stats->tx_packets; 1017 tbytes = stats->tx_bytes; 1018 } while (u64_stats_fetch_retry_irq(&stats->tx_syncp, start)); 1019 1020 do { 1021 start = u64_stats_fetch_begin_irq(&stats->rx_syncp); 1022 rpackets = stats->rx_packets; 1023 rbytes = stats->rx_bytes; 1024 } while (u64_stats_fetch_retry_irq(&stats->rx_syncp, start)); 1025 1026 tot->rx_packets += rpackets; 1027 tot->tx_packets += tpackets; 1028 tot->rx_bytes += rbytes; 1029 tot->tx_bytes += tbytes; 1030 } 1031 1032 tot->tx_dropped = dev->stats.tx_dropped; 1033 tot->tx_fifo_errors = dev->stats.tx_fifo_errors; 1034 tot->rx_dropped = dev->stats.rx_dropped; 1035 tot->rx_length_errors = dev->stats.rx_length_errors; 1036 tot->rx_frame_errors = dev->stats.rx_frame_errors; 1037 1038 return tot; 1039 } 1040 1041 #ifdef CONFIG_NET_POLL_CONTROLLER 1042 static void virtnet_netpoll(struct net_device *dev) 1043 { 1044 struct virtnet_info *vi = netdev_priv(dev); 1045 int i; 1046 1047 for (i = 0; i < vi->curr_queue_pairs; i++) 1048 napi_schedule(&vi->rq[i].napi); 1049 } 1050 #endif 1051 1052 static void virtnet_ack_link_announce(struct virtnet_info *vi) 1053 { 1054 rtnl_lock(); 1055 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_ANNOUNCE, 1056 VIRTIO_NET_CTRL_ANNOUNCE_ACK, NULL)) 1057 dev_warn(&vi->dev->dev, "Failed to ack link announce.\n"); 1058 rtnl_unlock(); 1059 } 1060 1061 static int virtnet_set_queues(struct virtnet_info *vi, u16 queue_pairs) 1062 { 1063 struct scatterlist sg; 1064 struct net_device *dev = vi->dev; 1065 1066 if (!vi->has_cvq || !virtio_has_feature(vi->vdev, VIRTIO_NET_F_MQ)) 1067 return 0; 1068 1069 vi->ctrl_mq.virtqueue_pairs = cpu_to_virtio16(vi->vdev, queue_pairs); 1070 sg_init_one(&sg, &vi->ctrl_mq, sizeof(vi->ctrl_mq)); 1071 1072 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_MQ, 1073 VIRTIO_NET_CTRL_MQ_VQ_PAIRS_SET, &sg)) { 1074 dev_warn(&dev->dev, "Fail to set num of queue pairs to %d\n", 1075 queue_pairs); 1076 return -EINVAL; 1077 } else { 1078 vi->curr_queue_pairs = queue_pairs; 1079 /* virtnet_open() will refill when device is going to up. */ 1080 if (dev->flags & IFF_UP) 1081 schedule_delayed_work(&vi->refill, 0); 1082 } 1083 1084 return 0; 1085 } 1086 1087 static int virtnet_close(struct net_device *dev) 1088 { 1089 struct virtnet_info *vi = netdev_priv(dev); 1090 int i; 1091 1092 /* Make sure refill_work doesn't re-enable napi! */ 1093 cancel_delayed_work_sync(&vi->refill); 1094 1095 for (i = 0; i < vi->max_queue_pairs; i++) 1096 napi_disable(&vi->rq[i].napi); 1097 1098 return 0; 1099 } 1100 1101 static void virtnet_set_rx_mode(struct net_device *dev) 1102 { 1103 struct virtnet_info *vi = netdev_priv(dev); 1104 struct scatterlist sg[2]; 1105 struct virtio_net_ctrl_mac *mac_data; 1106 struct netdev_hw_addr *ha; 1107 int uc_count; 1108 int mc_count; 1109 void *buf; 1110 int i; 1111 1112 /* We can't dynamically set ndo_set_rx_mode, so return gracefully */ 1113 if (!virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_RX)) 1114 return; 1115 1116 vi->ctrl_promisc = ((dev->flags & IFF_PROMISC) != 0); 1117 vi->ctrl_allmulti = ((dev->flags & IFF_ALLMULTI) != 0); 1118 1119 sg_init_one(sg, &vi->ctrl_promisc, sizeof(vi->ctrl_promisc)); 1120 1121 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_RX, 1122 VIRTIO_NET_CTRL_RX_PROMISC, sg)) 1123 dev_warn(&dev->dev, "Failed to %sable promisc mode.\n", 1124 vi->ctrl_promisc ? "en" : "dis"); 1125 1126 sg_init_one(sg, &vi->ctrl_allmulti, sizeof(vi->ctrl_allmulti)); 1127 1128 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_RX, 1129 VIRTIO_NET_CTRL_RX_ALLMULTI, sg)) 1130 dev_warn(&dev->dev, "Failed to %sable allmulti mode.\n", 1131 vi->ctrl_allmulti ? "en" : "dis"); 1132 1133 uc_count = netdev_uc_count(dev); 1134 mc_count = netdev_mc_count(dev); 1135 /* MAC filter - use one buffer for both lists */ 1136 buf = kzalloc(((uc_count + mc_count) * ETH_ALEN) + 1137 (2 * sizeof(mac_data->entries)), GFP_ATOMIC); 1138 mac_data = buf; 1139 if (!buf) 1140 return; 1141 1142 sg_init_table(sg, 2); 1143 1144 /* Store the unicast list and count in the front of the buffer */ 1145 mac_data->entries = cpu_to_virtio32(vi->vdev, uc_count); 1146 i = 0; 1147 netdev_for_each_uc_addr(ha, dev) 1148 memcpy(&mac_data->macs[i++][0], ha->addr, ETH_ALEN); 1149 1150 sg_set_buf(&sg[0], mac_data, 1151 sizeof(mac_data->entries) + (uc_count * ETH_ALEN)); 1152 1153 /* multicast list and count fill the end */ 1154 mac_data = (void *)&mac_data->macs[uc_count][0]; 1155 1156 mac_data->entries = cpu_to_virtio32(vi->vdev, mc_count); 1157 i = 0; 1158 netdev_for_each_mc_addr(ha, dev) 1159 memcpy(&mac_data->macs[i++][0], ha->addr, ETH_ALEN); 1160 1161 sg_set_buf(&sg[1], mac_data, 1162 sizeof(mac_data->entries) + (mc_count * ETH_ALEN)); 1163 1164 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_MAC, 1165 VIRTIO_NET_CTRL_MAC_TABLE_SET, sg)) 1166 dev_warn(&dev->dev, "Failed to set MAC filter table.\n"); 1167 1168 kfree(buf); 1169 } 1170 1171 static int virtnet_vlan_rx_add_vid(struct net_device *dev, 1172 __be16 proto, u16 vid) 1173 { 1174 struct virtnet_info *vi = netdev_priv(dev); 1175 struct scatterlist sg; 1176 1177 vi->ctrl_vid = vid; 1178 sg_init_one(&sg, &vi->ctrl_vid, sizeof(vi->ctrl_vid)); 1179 1180 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_VLAN, 1181 VIRTIO_NET_CTRL_VLAN_ADD, &sg)) 1182 dev_warn(&dev->dev, "Failed to add VLAN ID %d.\n", vid); 1183 return 0; 1184 } 1185 1186 static int virtnet_vlan_rx_kill_vid(struct net_device *dev, 1187 __be16 proto, u16 vid) 1188 { 1189 struct virtnet_info *vi = netdev_priv(dev); 1190 struct scatterlist sg; 1191 1192 vi->ctrl_vid = vid; 1193 sg_init_one(&sg, &vi->ctrl_vid, sizeof(vi->ctrl_vid)); 1194 1195 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_VLAN, 1196 VIRTIO_NET_CTRL_VLAN_DEL, &sg)) 1197 dev_warn(&dev->dev, "Failed to kill VLAN ID %d.\n", vid); 1198 return 0; 1199 } 1200 1201 static void virtnet_clean_affinity(struct virtnet_info *vi, long hcpu) 1202 { 1203 int i; 1204 1205 if (vi->affinity_hint_set) { 1206 for (i = 0; i < vi->max_queue_pairs; i++) { 1207 virtqueue_set_affinity(vi->rq[i].vq, -1); 1208 virtqueue_set_affinity(vi->sq[i].vq, -1); 1209 } 1210 1211 vi->affinity_hint_set = false; 1212 } 1213 } 1214 1215 static void virtnet_set_affinity(struct virtnet_info *vi) 1216 { 1217 int i; 1218 int cpu; 1219 1220 /* In multiqueue mode, when the number of cpu is equal to the number of 1221 * queue pairs, we let the queue pairs to be private to one cpu by 1222 * setting the affinity hint to eliminate the contention. 1223 */ 1224 if (vi->curr_queue_pairs == 1 || 1225 vi->max_queue_pairs != num_online_cpus()) { 1226 virtnet_clean_affinity(vi, -1); 1227 return; 1228 } 1229 1230 i = 0; 1231 for_each_online_cpu(cpu) { 1232 virtqueue_set_affinity(vi->rq[i].vq, cpu); 1233 virtqueue_set_affinity(vi->sq[i].vq, cpu); 1234 netif_set_xps_queue(vi->dev, cpumask_of(cpu), i); 1235 i++; 1236 } 1237 1238 vi->affinity_hint_set = true; 1239 } 1240 1241 static int virtnet_cpu_online(unsigned int cpu, struct hlist_node *node) 1242 { 1243 struct virtnet_info *vi = hlist_entry_safe(node, struct virtnet_info, 1244 node); 1245 virtnet_set_affinity(vi); 1246 return 0; 1247 } 1248 1249 static int virtnet_cpu_dead(unsigned int cpu, struct hlist_node *node) 1250 { 1251 struct virtnet_info *vi = hlist_entry_safe(node, struct virtnet_info, 1252 node_dead); 1253 virtnet_set_affinity(vi); 1254 return 0; 1255 } 1256 1257 static int virtnet_cpu_down_prep(unsigned int cpu, struct hlist_node *node) 1258 { 1259 struct virtnet_info *vi = hlist_entry_safe(node, struct virtnet_info, 1260 node); 1261 1262 virtnet_clean_affinity(vi, cpu); 1263 return 0; 1264 } 1265 1266 static enum cpuhp_state virtionet_online; 1267 1268 static int virtnet_cpu_notif_add(struct virtnet_info *vi) 1269 { 1270 int ret; 1271 1272 ret = cpuhp_state_add_instance_nocalls(virtionet_online, &vi->node); 1273 if (ret) 1274 return ret; 1275 ret = cpuhp_state_add_instance_nocalls(CPUHP_VIRT_NET_DEAD, 1276 &vi->node_dead); 1277 if (!ret) 1278 return ret; 1279 cpuhp_state_remove_instance_nocalls(virtionet_online, &vi->node); 1280 return ret; 1281 } 1282 1283 static void virtnet_cpu_notif_remove(struct virtnet_info *vi) 1284 { 1285 cpuhp_state_remove_instance_nocalls(virtionet_online, &vi->node); 1286 cpuhp_state_remove_instance_nocalls(CPUHP_VIRT_NET_DEAD, 1287 &vi->node_dead); 1288 } 1289 1290 static void virtnet_get_ringparam(struct net_device *dev, 1291 struct ethtool_ringparam *ring) 1292 { 1293 struct virtnet_info *vi = netdev_priv(dev); 1294 1295 ring->rx_max_pending = virtqueue_get_vring_size(vi->rq[0].vq); 1296 ring->tx_max_pending = virtqueue_get_vring_size(vi->sq[0].vq); 1297 ring->rx_pending = ring->rx_max_pending; 1298 ring->tx_pending = ring->tx_max_pending; 1299 } 1300 1301 1302 static void virtnet_get_drvinfo(struct net_device *dev, 1303 struct ethtool_drvinfo *info) 1304 { 1305 struct virtnet_info *vi = netdev_priv(dev); 1306 struct virtio_device *vdev = vi->vdev; 1307 1308 strlcpy(info->driver, KBUILD_MODNAME, sizeof(info->driver)); 1309 strlcpy(info->version, VIRTNET_DRIVER_VERSION, sizeof(info->version)); 1310 strlcpy(info->bus_info, virtio_bus_name(vdev), sizeof(info->bus_info)); 1311 1312 } 1313 1314 /* TODO: Eliminate OOO packets during switching */ 1315 static int virtnet_set_channels(struct net_device *dev, 1316 struct ethtool_channels *channels) 1317 { 1318 struct virtnet_info *vi = netdev_priv(dev); 1319 u16 queue_pairs = channels->combined_count; 1320 int err; 1321 1322 /* We don't support separate rx/tx channels. 1323 * We don't allow setting 'other' channels. 1324 */ 1325 if (channels->rx_count || channels->tx_count || channels->other_count) 1326 return -EINVAL; 1327 1328 if (queue_pairs > vi->max_queue_pairs || queue_pairs == 0) 1329 return -EINVAL; 1330 1331 get_online_cpus(); 1332 err = virtnet_set_queues(vi, queue_pairs); 1333 if (!err) { 1334 netif_set_real_num_tx_queues(dev, queue_pairs); 1335 netif_set_real_num_rx_queues(dev, queue_pairs); 1336 1337 virtnet_set_affinity(vi); 1338 } 1339 put_online_cpus(); 1340 1341 return err; 1342 } 1343 1344 static void virtnet_get_channels(struct net_device *dev, 1345 struct ethtool_channels *channels) 1346 { 1347 struct virtnet_info *vi = netdev_priv(dev); 1348 1349 channels->combined_count = vi->curr_queue_pairs; 1350 channels->max_combined = vi->max_queue_pairs; 1351 channels->max_other = 0; 1352 channels->rx_count = 0; 1353 channels->tx_count = 0; 1354 channels->other_count = 0; 1355 } 1356 1357 /* Check if the user is trying to change anything besides speed/duplex */ 1358 static bool virtnet_validate_ethtool_cmd(const struct ethtool_cmd *cmd) 1359 { 1360 struct ethtool_cmd diff1 = *cmd; 1361 struct ethtool_cmd diff2 = {}; 1362 1363 /* cmd is always set so we need to clear it, validate the port type 1364 * and also without autonegotiation we can ignore advertising 1365 */ 1366 ethtool_cmd_speed_set(&diff1, 0); 1367 diff2.port = PORT_OTHER; 1368 diff1.advertising = 0; 1369 diff1.duplex = 0; 1370 diff1.cmd = 0; 1371 1372 return !memcmp(&diff1, &diff2, sizeof(diff1)); 1373 } 1374 1375 static int virtnet_set_settings(struct net_device *dev, struct ethtool_cmd *cmd) 1376 { 1377 struct virtnet_info *vi = netdev_priv(dev); 1378 u32 speed; 1379 1380 speed = ethtool_cmd_speed(cmd); 1381 /* don't allow custom speed and duplex */ 1382 if (!ethtool_validate_speed(speed) || 1383 !ethtool_validate_duplex(cmd->duplex) || 1384 !virtnet_validate_ethtool_cmd(cmd)) 1385 return -EINVAL; 1386 vi->speed = speed; 1387 vi->duplex = cmd->duplex; 1388 1389 return 0; 1390 } 1391 1392 static int virtnet_get_settings(struct net_device *dev, struct ethtool_cmd *cmd) 1393 { 1394 struct virtnet_info *vi = netdev_priv(dev); 1395 1396 ethtool_cmd_speed_set(cmd, vi->speed); 1397 cmd->duplex = vi->duplex; 1398 cmd->port = PORT_OTHER; 1399 1400 return 0; 1401 } 1402 1403 static void virtnet_init_settings(struct net_device *dev) 1404 { 1405 struct virtnet_info *vi = netdev_priv(dev); 1406 1407 vi->speed = SPEED_UNKNOWN; 1408 vi->duplex = DUPLEX_UNKNOWN; 1409 } 1410 1411 static const struct ethtool_ops virtnet_ethtool_ops = { 1412 .get_drvinfo = virtnet_get_drvinfo, 1413 .get_link = ethtool_op_get_link, 1414 .get_ringparam = virtnet_get_ringparam, 1415 .set_channels = virtnet_set_channels, 1416 .get_channels = virtnet_get_channels, 1417 .get_ts_info = ethtool_op_get_ts_info, 1418 .get_settings = virtnet_get_settings, 1419 .set_settings = virtnet_set_settings, 1420 }; 1421 1422 #define MIN_MTU 68 1423 #define MAX_MTU 65535 1424 1425 static int virtnet_change_mtu(struct net_device *dev, int new_mtu) 1426 { 1427 if (new_mtu < MIN_MTU || new_mtu > MAX_MTU) 1428 return -EINVAL; 1429 dev->mtu = new_mtu; 1430 return 0; 1431 } 1432 1433 static const struct net_device_ops virtnet_netdev = { 1434 .ndo_open = virtnet_open, 1435 .ndo_stop = virtnet_close, 1436 .ndo_start_xmit = start_xmit, 1437 .ndo_validate_addr = eth_validate_addr, 1438 .ndo_set_mac_address = virtnet_set_mac_address, 1439 .ndo_set_rx_mode = virtnet_set_rx_mode, 1440 .ndo_change_mtu = virtnet_change_mtu, 1441 .ndo_get_stats64 = virtnet_stats, 1442 .ndo_vlan_rx_add_vid = virtnet_vlan_rx_add_vid, 1443 .ndo_vlan_rx_kill_vid = virtnet_vlan_rx_kill_vid, 1444 #ifdef CONFIG_NET_POLL_CONTROLLER 1445 .ndo_poll_controller = virtnet_netpoll, 1446 #endif 1447 #ifdef CONFIG_NET_RX_BUSY_POLL 1448 .ndo_busy_poll = virtnet_busy_poll, 1449 #endif 1450 }; 1451 1452 static void virtnet_config_changed_work(struct work_struct *work) 1453 { 1454 struct virtnet_info *vi = 1455 container_of(work, struct virtnet_info, config_work); 1456 u16 v; 1457 1458 if (virtio_cread_feature(vi->vdev, VIRTIO_NET_F_STATUS, 1459 struct virtio_net_config, status, &v) < 0) 1460 return; 1461 1462 if (v & VIRTIO_NET_S_ANNOUNCE) { 1463 netdev_notify_peers(vi->dev); 1464 virtnet_ack_link_announce(vi); 1465 } 1466 1467 /* Ignore unknown (future) status bits */ 1468 v &= VIRTIO_NET_S_LINK_UP; 1469 1470 if (vi->status == v) 1471 return; 1472 1473 vi->status = v; 1474 1475 if (vi->status & VIRTIO_NET_S_LINK_UP) { 1476 netif_carrier_on(vi->dev); 1477 netif_tx_wake_all_queues(vi->dev); 1478 } else { 1479 netif_carrier_off(vi->dev); 1480 netif_tx_stop_all_queues(vi->dev); 1481 } 1482 } 1483 1484 static void virtnet_config_changed(struct virtio_device *vdev) 1485 { 1486 struct virtnet_info *vi = vdev->priv; 1487 1488 schedule_work(&vi->config_work); 1489 } 1490 1491 static void virtnet_free_queues(struct virtnet_info *vi) 1492 { 1493 int i; 1494 1495 for (i = 0; i < vi->max_queue_pairs; i++) { 1496 napi_hash_del(&vi->rq[i].napi); 1497 netif_napi_del(&vi->rq[i].napi); 1498 } 1499 1500 kfree(vi->rq); 1501 kfree(vi->sq); 1502 } 1503 1504 static void free_receive_bufs(struct virtnet_info *vi) 1505 { 1506 int i; 1507 1508 for (i = 0; i < vi->max_queue_pairs; i++) { 1509 while (vi->rq[i].pages) 1510 __free_pages(get_a_page(&vi->rq[i], GFP_KERNEL), 0); 1511 } 1512 } 1513 1514 static void free_receive_page_frags(struct virtnet_info *vi) 1515 { 1516 int i; 1517 for (i = 0; i < vi->max_queue_pairs; i++) 1518 if (vi->rq[i].alloc_frag.page) 1519 put_page(vi->rq[i].alloc_frag.page); 1520 } 1521 1522 static void free_unused_bufs(struct virtnet_info *vi) 1523 { 1524 void *buf; 1525 int i; 1526 1527 for (i = 0; i < vi->max_queue_pairs; i++) { 1528 struct virtqueue *vq = vi->sq[i].vq; 1529 while ((buf = virtqueue_detach_unused_buf(vq)) != NULL) 1530 dev_kfree_skb(buf); 1531 } 1532 1533 for (i = 0; i < vi->max_queue_pairs; i++) { 1534 struct virtqueue *vq = vi->rq[i].vq; 1535 1536 while ((buf = virtqueue_detach_unused_buf(vq)) != NULL) { 1537 if (vi->mergeable_rx_bufs) { 1538 unsigned long ctx = (unsigned long)buf; 1539 void *base = mergeable_ctx_to_buf_address(ctx); 1540 put_page(virt_to_head_page(base)); 1541 } else if (vi->big_packets) { 1542 give_pages(&vi->rq[i], buf); 1543 } else { 1544 dev_kfree_skb(buf); 1545 } 1546 } 1547 } 1548 } 1549 1550 static void virtnet_del_vqs(struct virtnet_info *vi) 1551 { 1552 struct virtio_device *vdev = vi->vdev; 1553 1554 virtnet_clean_affinity(vi, -1); 1555 1556 vdev->config->del_vqs(vdev); 1557 1558 virtnet_free_queues(vi); 1559 } 1560 1561 static int virtnet_find_vqs(struct virtnet_info *vi) 1562 { 1563 vq_callback_t **callbacks; 1564 struct virtqueue **vqs; 1565 int ret = -ENOMEM; 1566 int i, total_vqs; 1567 const char **names; 1568 1569 /* We expect 1 RX virtqueue followed by 1 TX virtqueue, followed by 1570 * possible N-1 RX/TX queue pairs used in multiqueue mode, followed by 1571 * possible control vq. 1572 */ 1573 total_vqs = vi->max_queue_pairs * 2 + 1574 virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ); 1575 1576 /* Allocate space for find_vqs parameters */ 1577 vqs = kzalloc(total_vqs * sizeof(*vqs), GFP_KERNEL); 1578 if (!vqs) 1579 goto err_vq; 1580 callbacks = kmalloc(total_vqs * sizeof(*callbacks), GFP_KERNEL); 1581 if (!callbacks) 1582 goto err_callback; 1583 names = kmalloc(total_vqs * sizeof(*names), GFP_KERNEL); 1584 if (!names) 1585 goto err_names; 1586 1587 /* Parameters for control virtqueue, if any */ 1588 if (vi->has_cvq) { 1589 callbacks[total_vqs - 1] = NULL; 1590 names[total_vqs - 1] = "control"; 1591 } 1592 1593 /* Allocate/initialize parameters for send/receive virtqueues */ 1594 for (i = 0; i < vi->max_queue_pairs; i++) { 1595 callbacks[rxq2vq(i)] = skb_recv_done; 1596 callbacks[txq2vq(i)] = skb_xmit_done; 1597 sprintf(vi->rq[i].name, "input.%d", i); 1598 sprintf(vi->sq[i].name, "output.%d", i); 1599 names[rxq2vq(i)] = vi->rq[i].name; 1600 names[txq2vq(i)] = vi->sq[i].name; 1601 } 1602 1603 ret = vi->vdev->config->find_vqs(vi->vdev, total_vqs, vqs, callbacks, 1604 names); 1605 if (ret) 1606 goto err_find; 1607 1608 if (vi->has_cvq) { 1609 vi->cvq = vqs[total_vqs - 1]; 1610 if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VLAN)) 1611 vi->dev->features |= NETIF_F_HW_VLAN_CTAG_FILTER; 1612 } 1613 1614 for (i = 0; i < vi->max_queue_pairs; i++) { 1615 vi->rq[i].vq = vqs[rxq2vq(i)]; 1616 vi->sq[i].vq = vqs[txq2vq(i)]; 1617 } 1618 1619 kfree(names); 1620 kfree(callbacks); 1621 kfree(vqs); 1622 1623 return 0; 1624 1625 err_find: 1626 kfree(names); 1627 err_names: 1628 kfree(callbacks); 1629 err_callback: 1630 kfree(vqs); 1631 err_vq: 1632 return ret; 1633 } 1634 1635 static int virtnet_alloc_queues(struct virtnet_info *vi) 1636 { 1637 int i; 1638 1639 vi->sq = kzalloc(sizeof(*vi->sq) * vi->max_queue_pairs, GFP_KERNEL); 1640 if (!vi->sq) 1641 goto err_sq; 1642 vi->rq = kzalloc(sizeof(*vi->rq) * vi->max_queue_pairs, GFP_KERNEL); 1643 if (!vi->rq) 1644 goto err_rq; 1645 1646 INIT_DELAYED_WORK(&vi->refill, refill_work); 1647 for (i = 0; i < vi->max_queue_pairs; i++) { 1648 vi->rq[i].pages = NULL; 1649 netif_napi_add(vi->dev, &vi->rq[i].napi, virtnet_poll, 1650 napi_weight); 1651 1652 sg_init_table(vi->rq[i].sg, ARRAY_SIZE(vi->rq[i].sg)); 1653 ewma_pkt_len_init(&vi->rq[i].mrg_avg_pkt_len); 1654 sg_init_table(vi->sq[i].sg, ARRAY_SIZE(vi->sq[i].sg)); 1655 } 1656 1657 return 0; 1658 1659 err_rq: 1660 kfree(vi->sq); 1661 err_sq: 1662 return -ENOMEM; 1663 } 1664 1665 static int init_vqs(struct virtnet_info *vi) 1666 { 1667 int ret; 1668 1669 /* Allocate send & receive queues */ 1670 ret = virtnet_alloc_queues(vi); 1671 if (ret) 1672 goto err; 1673 1674 ret = virtnet_find_vqs(vi); 1675 if (ret) 1676 goto err_free; 1677 1678 get_online_cpus(); 1679 virtnet_set_affinity(vi); 1680 put_online_cpus(); 1681 1682 return 0; 1683 1684 err_free: 1685 virtnet_free_queues(vi); 1686 err: 1687 return ret; 1688 } 1689 1690 #ifdef CONFIG_SYSFS 1691 static ssize_t mergeable_rx_buffer_size_show(struct netdev_rx_queue *queue, 1692 struct rx_queue_attribute *attribute, char *buf) 1693 { 1694 struct virtnet_info *vi = netdev_priv(queue->dev); 1695 unsigned int queue_index = get_netdev_rx_queue_index(queue); 1696 struct ewma_pkt_len *avg; 1697 1698 BUG_ON(queue_index >= vi->max_queue_pairs); 1699 avg = &vi->rq[queue_index].mrg_avg_pkt_len; 1700 return sprintf(buf, "%u\n", get_mergeable_buf_len(avg)); 1701 } 1702 1703 static struct rx_queue_attribute mergeable_rx_buffer_size_attribute = 1704 __ATTR_RO(mergeable_rx_buffer_size); 1705 1706 static struct attribute *virtio_net_mrg_rx_attrs[] = { 1707 &mergeable_rx_buffer_size_attribute.attr, 1708 NULL 1709 }; 1710 1711 static const struct attribute_group virtio_net_mrg_rx_group = { 1712 .name = "virtio_net", 1713 .attrs = virtio_net_mrg_rx_attrs 1714 }; 1715 #endif 1716 1717 static bool virtnet_fail_on_feature(struct virtio_device *vdev, 1718 unsigned int fbit, 1719 const char *fname, const char *dname) 1720 { 1721 if (!virtio_has_feature(vdev, fbit)) 1722 return false; 1723 1724 dev_err(&vdev->dev, "device advertises feature %s but not %s", 1725 fname, dname); 1726 1727 return true; 1728 } 1729 1730 #define VIRTNET_FAIL_ON(vdev, fbit, dbit) \ 1731 virtnet_fail_on_feature(vdev, fbit, #fbit, dbit) 1732 1733 static bool virtnet_validate_features(struct virtio_device *vdev) 1734 { 1735 if (!virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_VQ) && 1736 (VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_CTRL_RX, 1737 "VIRTIO_NET_F_CTRL_VQ") || 1738 VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_CTRL_VLAN, 1739 "VIRTIO_NET_F_CTRL_VQ") || 1740 VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_GUEST_ANNOUNCE, 1741 "VIRTIO_NET_F_CTRL_VQ") || 1742 VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_MQ, "VIRTIO_NET_F_CTRL_VQ") || 1743 VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_CTRL_MAC_ADDR, 1744 "VIRTIO_NET_F_CTRL_VQ"))) { 1745 return false; 1746 } 1747 1748 return true; 1749 } 1750 1751 static int virtnet_probe(struct virtio_device *vdev) 1752 { 1753 int i, err; 1754 struct net_device *dev; 1755 struct virtnet_info *vi; 1756 u16 max_queue_pairs; 1757 int mtu; 1758 1759 if (!vdev->config->get) { 1760 dev_err(&vdev->dev, "%s failure: config access disabled\n", 1761 __func__); 1762 return -EINVAL; 1763 } 1764 1765 if (!virtnet_validate_features(vdev)) 1766 return -EINVAL; 1767 1768 /* Find if host supports multiqueue virtio_net device */ 1769 err = virtio_cread_feature(vdev, VIRTIO_NET_F_MQ, 1770 struct virtio_net_config, 1771 max_virtqueue_pairs, &max_queue_pairs); 1772 1773 /* We need at least 2 queue's */ 1774 if (err || max_queue_pairs < VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MIN || 1775 max_queue_pairs > VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MAX || 1776 !virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_VQ)) 1777 max_queue_pairs = 1; 1778 1779 /* Allocate ourselves a network device with room for our info */ 1780 dev = alloc_etherdev_mq(sizeof(struct virtnet_info), max_queue_pairs); 1781 if (!dev) 1782 return -ENOMEM; 1783 1784 /* Set up network device as normal. */ 1785 dev->priv_flags |= IFF_UNICAST_FLT | IFF_LIVE_ADDR_CHANGE; 1786 dev->netdev_ops = &virtnet_netdev; 1787 dev->features = NETIF_F_HIGHDMA; 1788 1789 dev->ethtool_ops = &virtnet_ethtool_ops; 1790 SET_NETDEV_DEV(dev, &vdev->dev); 1791 1792 /* Do we support "hardware" checksums? */ 1793 if (virtio_has_feature(vdev, VIRTIO_NET_F_CSUM)) { 1794 /* This opens up the world of extra features. */ 1795 dev->hw_features |= NETIF_F_HW_CSUM | NETIF_F_SG; 1796 if (csum) 1797 dev->features |= NETIF_F_HW_CSUM | NETIF_F_SG; 1798 1799 if (virtio_has_feature(vdev, VIRTIO_NET_F_GSO)) { 1800 dev->hw_features |= NETIF_F_TSO | NETIF_F_UFO 1801 | NETIF_F_TSO_ECN | NETIF_F_TSO6; 1802 } 1803 /* Individual feature bits: what can host handle? */ 1804 if (virtio_has_feature(vdev, VIRTIO_NET_F_HOST_TSO4)) 1805 dev->hw_features |= NETIF_F_TSO; 1806 if (virtio_has_feature(vdev, VIRTIO_NET_F_HOST_TSO6)) 1807 dev->hw_features |= NETIF_F_TSO6; 1808 if (virtio_has_feature(vdev, VIRTIO_NET_F_HOST_ECN)) 1809 dev->hw_features |= NETIF_F_TSO_ECN; 1810 if (virtio_has_feature(vdev, VIRTIO_NET_F_HOST_UFO)) 1811 dev->hw_features |= NETIF_F_UFO; 1812 1813 dev->features |= NETIF_F_GSO_ROBUST; 1814 1815 if (gso) 1816 dev->features |= dev->hw_features & (NETIF_F_ALL_TSO|NETIF_F_UFO); 1817 /* (!csum && gso) case will be fixed by register_netdev() */ 1818 } 1819 if (virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_CSUM)) 1820 dev->features |= NETIF_F_RXCSUM; 1821 1822 dev->vlan_features = dev->features; 1823 1824 /* Configuration may specify what MAC to use. Otherwise random. */ 1825 if (virtio_has_feature(vdev, VIRTIO_NET_F_MAC)) 1826 virtio_cread_bytes(vdev, 1827 offsetof(struct virtio_net_config, mac), 1828 dev->dev_addr, dev->addr_len); 1829 else 1830 eth_hw_addr_random(dev); 1831 1832 /* Set up our device-specific information */ 1833 vi = netdev_priv(dev); 1834 vi->dev = dev; 1835 vi->vdev = vdev; 1836 vdev->priv = vi; 1837 vi->stats = alloc_percpu(struct virtnet_stats); 1838 err = -ENOMEM; 1839 if (vi->stats == NULL) 1840 goto free; 1841 1842 for_each_possible_cpu(i) { 1843 struct virtnet_stats *virtnet_stats; 1844 virtnet_stats = per_cpu_ptr(vi->stats, i); 1845 u64_stats_init(&virtnet_stats->tx_syncp); 1846 u64_stats_init(&virtnet_stats->rx_syncp); 1847 } 1848 1849 INIT_WORK(&vi->config_work, virtnet_config_changed_work); 1850 1851 /* If we can receive ANY GSO packets, we must allocate large ones. */ 1852 if (virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_TSO4) || 1853 virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_TSO6) || 1854 virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_ECN) || 1855 virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_UFO)) 1856 vi->big_packets = true; 1857 1858 if (virtio_has_feature(vdev, VIRTIO_NET_F_MRG_RXBUF)) 1859 vi->mergeable_rx_bufs = true; 1860 1861 if (virtio_has_feature(vdev, VIRTIO_NET_F_MRG_RXBUF) || 1862 virtio_has_feature(vdev, VIRTIO_F_VERSION_1)) 1863 vi->hdr_len = sizeof(struct virtio_net_hdr_mrg_rxbuf); 1864 else 1865 vi->hdr_len = sizeof(struct virtio_net_hdr); 1866 1867 if (virtio_has_feature(vdev, VIRTIO_F_ANY_LAYOUT) || 1868 virtio_has_feature(vdev, VIRTIO_F_VERSION_1)) 1869 vi->any_header_sg = true; 1870 1871 if (virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_VQ)) 1872 vi->has_cvq = true; 1873 1874 if (virtio_has_feature(vdev, VIRTIO_NET_F_MTU)) { 1875 mtu = virtio_cread16(vdev, 1876 offsetof(struct virtio_net_config, 1877 mtu)); 1878 if (virtnet_change_mtu(dev, mtu)) 1879 __virtio_clear_bit(vdev, VIRTIO_NET_F_MTU); 1880 } 1881 1882 if (vi->any_header_sg) 1883 dev->needed_headroom = vi->hdr_len; 1884 1885 /* Use single tx/rx queue pair as default */ 1886 vi->curr_queue_pairs = 1; 1887 vi->max_queue_pairs = max_queue_pairs; 1888 1889 /* Allocate/initialize the rx/tx queues, and invoke find_vqs */ 1890 err = init_vqs(vi); 1891 if (err) 1892 goto free_stats; 1893 1894 #ifdef CONFIG_SYSFS 1895 if (vi->mergeable_rx_bufs) 1896 dev->sysfs_rx_queue_group = &virtio_net_mrg_rx_group; 1897 #endif 1898 netif_set_real_num_tx_queues(dev, vi->curr_queue_pairs); 1899 netif_set_real_num_rx_queues(dev, vi->curr_queue_pairs); 1900 1901 virtnet_init_settings(dev); 1902 1903 err = register_netdev(dev); 1904 if (err) { 1905 pr_debug("virtio_net: registering device failed\n"); 1906 goto free_vqs; 1907 } 1908 1909 virtio_device_ready(vdev); 1910 1911 err = virtnet_cpu_notif_add(vi); 1912 if (err) { 1913 pr_debug("virtio_net: registering cpu notifier failed\n"); 1914 goto free_unregister_netdev; 1915 } 1916 1917 /* Assume link up if device can't report link status, 1918 otherwise get link status from config. */ 1919 if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_STATUS)) { 1920 netif_carrier_off(dev); 1921 schedule_work(&vi->config_work); 1922 } else { 1923 vi->status = VIRTIO_NET_S_LINK_UP; 1924 netif_carrier_on(dev); 1925 } 1926 1927 pr_debug("virtnet: registered device %s with %d RX and TX vq's\n", 1928 dev->name, max_queue_pairs); 1929 1930 return 0; 1931 1932 free_unregister_netdev: 1933 vi->vdev->config->reset(vdev); 1934 1935 unregister_netdev(dev); 1936 free_vqs: 1937 cancel_delayed_work_sync(&vi->refill); 1938 free_receive_page_frags(vi); 1939 virtnet_del_vqs(vi); 1940 free_stats: 1941 free_percpu(vi->stats); 1942 free: 1943 free_netdev(dev); 1944 return err; 1945 } 1946 1947 static void remove_vq_common(struct virtnet_info *vi) 1948 { 1949 vi->vdev->config->reset(vi->vdev); 1950 1951 /* Free unused buffers in both send and recv, if any. */ 1952 free_unused_bufs(vi); 1953 1954 free_receive_bufs(vi); 1955 1956 free_receive_page_frags(vi); 1957 1958 virtnet_del_vqs(vi); 1959 } 1960 1961 static void virtnet_remove(struct virtio_device *vdev) 1962 { 1963 struct virtnet_info *vi = vdev->priv; 1964 1965 virtnet_cpu_notif_remove(vi); 1966 1967 /* Make sure no work handler is accessing the device. */ 1968 flush_work(&vi->config_work); 1969 1970 unregister_netdev(vi->dev); 1971 1972 remove_vq_common(vi); 1973 1974 free_percpu(vi->stats); 1975 free_netdev(vi->dev); 1976 } 1977 1978 #ifdef CONFIG_PM_SLEEP 1979 static int virtnet_freeze(struct virtio_device *vdev) 1980 { 1981 struct virtnet_info *vi = vdev->priv; 1982 int i; 1983 1984 virtnet_cpu_notif_remove(vi); 1985 1986 /* Make sure no work handler is accessing the device */ 1987 flush_work(&vi->config_work); 1988 1989 netif_device_detach(vi->dev); 1990 cancel_delayed_work_sync(&vi->refill); 1991 1992 if (netif_running(vi->dev)) { 1993 for (i = 0; i < vi->max_queue_pairs; i++) 1994 napi_disable(&vi->rq[i].napi); 1995 } 1996 1997 remove_vq_common(vi); 1998 1999 return 0; 2000 } 2001 2002 static int virtnet_restore(struct virtio_device *vdev) 2003 { 2004 struct virtnet_info *vi = vdev->priv; 2005 int err, i; 2006 2007 err = init_vqs(vi); 2008 if (err) 2009 return err; 2010 2011 virtio_device_ready(vdev); 2012 2013 if (netif_running(vi->dev)) { 2014 for (i = 0; i < vi->curr_queue_pairs; i++) 2015 if (!try_fill_recv(vi, &vi->rq[i], GFP_KERNEL)) 2016 schedule_delayed_work(&vi->refill, 0); 2017 2018 for (i = 0; i < vi->max_queue_pairs; i++) 2019 virtnet_napi_enable(&vi->rq[i]); 2020 } 2021 2022 netif_device_attach(vi->dev); 2023 2024 rtnl_lock(); 2025 virtnet_set_queues(vi, vi->curr_queue_pairs); 2026 rtnl_unlock(); 2027 2028 err = virtnet_cpu_notif_add(vi); 2029 if (err) 2030 return err; 2031 2032 return 0; 2033 } 2034 #endif 2035 2036 static struct virtio_device_id id_table[] = { 2037 { VIRTIO_ID_NET, VIRTIO_DEV_ANY_ID }, 2038 { 0 }, 2039 }; 2040 2041 static unsigned int features[] = { 2042 VIRTIO_NET_F_CSUM, VIRTIO_NET_F_GUEST_CSUM, 2043 VIRTIO_NET_F_GSO, VIRTIO_NET_F_MAC, 2044 VIRTIO_NET_F_HOST_TSO4, VIRTIO_NET_F_HOST_UFO, VIRTIO_NET_F_HOST_TSO6, 2045 VIRTIO_NET_F_HOST_ECN, VIRTIO_NET_F_GUEST_TSO4, VIRTIO_NET_F_GUEST_TSO6, 2046 VIRTIO_NET_F_GUEST_ECN, VIRTIO_NET_F_GUEST_UFO, 2047 VIRTIO_NET_F_MRG_RXBUF, VIRTIO_NET_F_STATUS, VIRTIO_NET_F_CTRL_VQ, 2048 VIRTIO_NET_F_CTRL_RX, VIRTIO_NET_F_CTRL_VLAN, 2049 VIRTIO_NET_F_GUEST_ANNOUNCE, VIRTIO_NET_F_MQ, 2050 VIRTIO_NET_F_CTRL_MAC_ADDR, 2051 VIRTIO_F_ANY_LAYOUT, 2052 VIRTIO_NET_F_MTU, 2053 }; 2054 2055 static struct virtio_driver virtio_net_driver = { 2056 .feature_table = features, 2057 .feature_table_size = ARRAY_SIZE(features), 2058 .driver.name = KBUILD_MODNAME, 2059 .driver.owner = THIS_MODULE, 2060 .id_table = id_table, 2061 .probe = virtnet_probe, 2062 .remove = virtnet_remove, 2063 .config_changed = virtnet_config_changed, 2064 #ifdef CONFIG_PM_SLEEP 2065 .freeze = virtnet_freeze, 2066 .restore = virtnet_restore, 2067 #endif 2068 }; 2069 2070 static __init int virtio_net_driver_init(void) 2071 { 2072 int ret; 2073 2074 ret = cpuhp_setup_state_multi(CPUHP_AP_ONLINE_DYN, "AP_VIRT_NET_ONLINE", 2075 virtnet_cpu_online, 2076 virtnet_cpu_down_prep); 2077 if (ret < 0) 2078 goto out; 2079 virtionet_online = ret; 2080 ret = cpuhp_setup_state_multi(CPUHP_VIRT_NET_DEAD, "VIRT_NET_DEAD", 2081 NULL, virtnet_cpu_dead); 2082 if (ret) 2083 goto err_dead; 2084 2085 ret = register_virtio_driver(&virtio_net_driver); 2086 if (ret) 2087 goto err_virtio; 2088 return 0; 2089 err_virtio: 2090 cpuhp_remove_multi_state(CPUHP_VIRT_NET_DEAD); 2091 err_dead: 2092 cpuhp_remove_multi_state(virtionet_online); 2093 out: 2094 return ret; 2095 } 2096 module_init(virtio_net_driver_init); 2097 2098 static __exit void virtio_net_driver_exit(void) 2099 { 2100 cpuhp_remove_multi_state(CPUHP_VIRT_NET_DEAD); 2101 cpuhp_remove_multi_state(virtionet_online); 2102 unregister_virtio_driver(&virtio_net_driver); 2103 } 2104 module_exit(virtio_net_driver_exit); 2105 2106 MODULE_DEVICE_TABLE(virtio, id_table); 2107 MODULE_DESCRIPTION("Virtio network driver"); 2108 MODULE_LICENSE("GPL"); 2109