1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* A network driver using virtio. 3 * 4 * Copyright 2007 Rusty Russell <rusty@rustcorp.com.au> IBM Corporation 5 */ 6 //#define DEBUG 7 #include <linux/netdevice.h> 8 #include <linux/etherdevice.h> 9 #include <linux/ethtool.h> 10 #include <linux/module.h> 11 #include <linux/virtio.h> 12 #include <linux/virtio_net.h> 13 #include <linux/bpf.h> 14 #include <linux/bpf_trace.h> 15 #include <linux/scatterlist.h> 16 #include <linux/if_vlan.h> 17 #include <linux/slab.h> 18 #include <linux/cpu.h> 19 #include <linux/average.h> 20 #include <linux/filter.h> 21 #include <linux/kernel.h> 22 #include <net/route.h> 23 #include <net/xdp.h> 24 #include <net/net_failover.h> 25 26 static int napi_weight = NAPI_POLL_WEIGHT; 27 module_param(napi_weight, int, 0444); 28 29 static bool csum = true, gso = true, napi_tx = true; 30 module_param(csum, bool, 0444); 31 module_param(gso, bool, 0444); 32 module_param(napi_tx, bool, 0644); 33 34 /* FIXME: MTU in config. */ 35 #define GOOD_PACKET_LEN (ETH_HLEN + VLAN_HLEN + ETH_DATA_LEN) 36 #define GOOD_COPY_LEN 128 37 38 #define VIRTNET_RX_PAD (NET_IP_ALIGN + NET_SKB_PAD) 39 40 /* Amount of XDP headroom to prepend to packets for use by xdp_adjust_head */ 41 #define VIRTIO_XDP_HEADROOM 256 42 43 /* Separating two types of XDP xmit */ 44 #define VIRTIO_XDP_TX BIT(0) 45 #define VIRTIO_XDP_REDIR BIT(1) 46 47 #define VIRTIO_XDP_FLAG BIT(0) 48 49 /* RX packet size EWMA. The average packet size is used to determine the packet 50 * buffer size when refilling RX rings. As the entire RX ring may be refilled 51 * at once, the weight is chosen so that the EWMA will be insensitive to short- 52 * term, transient changes in packet size. 53 */ 54 DECLARE_EWMA(pkt_len, 0, 64) 55 56 #define VIRTNET_DRIVER_VERSION "1.0.0" 57 58 static const unsigned long guest_offloads[] = { 59 VIRTIO_NET_F_GUEST_TSO4, 60 VIRTIO_NET_F_GUEST_TSO6, 61 VIRTIO_NET_F_GUEST_ECN, 62 VIRTIO_NET_F_GUEST_UFO, 63 VIRTIO_NET_F_GUEST_CSUM 64 }; 65 66 #define GUEST_OFFLOAD_GRO_HW_MASK ((1ULL << VIRTIO_NET_F_GUEST_TSO4) | \ 67 (1ULL << VIRTIO_NET_F_GUEST_TSO6) | \ 68 (1ULL << VIRTIO_NET_F_GUEST_ECN) | \ 69 (1ULL << VIRTIO_NET_F_GUEST_UFO)) 70 71 struct virtnet_stat_desc { 72 char desc[ETH_GSTRING_LEN]; 73 size_t offset; 74 }; 75 76 struct virtnet_sq_stats { 77 struct u64_stats_sync syncp; 78 u64 packets; 79 u64 bytes; 80 u64 xdp_tx; 81 u64 xdp_tx_drops; 82 u64 kicks; 83 u64 tx_timeouts; 84 }; 85 86 struct virtnet_rq_stats { 87 struct u64_stats_sync syncp; 88 u64 packets; 89 u64 bytes; 90 u64 drops; 91 u64 xdp_packets; 92 u64 xdp_tx; 93 u64 xdp_redirects; 94 u64 xdp_drops; 95 u64 kicks; 96 }; 97 98 #define VIRTNET_SQ_STAT(m) offsetof(struct virtnet_sq_stats, m) 99 #define VIRTNET_RQ_STAT(m) offsetof(struct virtnet_rq_stats, m) 100 101 static const struct virtnet_stat_desc virtnet_sq_stats_desc[] = { 102 { "packets", VIRTNET_SQ_STAT(packets) }, 103 { "bytes", VIRTNET_SQ_STAT(bytes) }, 104 { "xdp_tx", VIRTNET_SQ_STAT(xdp_tx) }, 105 { "xdp_tx_drops", VIRTNET_SQ_STAT(xdp_tx_drops) }, 106 { "kicks", VIRTNET_SQ_STAT(kicks) }, 107 { "tx_timeouts", VIRTNET_SQ_STAT(tx_timeouts) }, 108 }; 109 110 static const struct virtnet_stat_desc virtnet_rq_stats_desc[] = { 111 { "packets", VIRTNET_RQ_STAT(packets) }, 112 { "bytes", VIRTNET_RQ_STAT(bytes) }, 113 { "drops", VIRTNET_RQ_STAT(drops) }, 114 { "xdp_packets", VIRTNET_RQ_STAT(xdp_packets) }, 115 { "xdp_tx", VIRTNET_RQ_STAT(xdp_tx) }, 116 { "xdp_redirects", VIRTNET_RQ_STAT(xdp_redirects) }, 117 { "xdp_drops", VIRTNET_RQ_STAT(xdp_drops) }, 118 { "kicks", VIRTNET_RQ_STAT(kicks) }, 119 }; 120 121 #define VIRTNET_SQ_STATS_LEN ARRAY_SIZE(virtnet_sq_stats_desc) 122 #define VIRTNET_RQ_STATS_LEN ARRAY_SIZE(virtnet_rq_stats_desc) 123 124 /* Internal representation of a send virtqueue */ 125 struct send_queue { 126 /* Virtqueue associated with this send _queue */ 127 struct virtqueue *vq; 128 129 /* TX: fragments + linear part + virtio header */ 130 struct scatterlist sg[MAX_SKB_FRAGS + 2]; 131 132 /* Name of the send queue: output.$index */ 133 char name[40]; 134 135 struct virtnet_sq_stats stats; 136 137 struct napi_struct napi; 138 139 /* Record whether sq is in reset state. */ 140 bool reset; 141 }; 142 143 /* Internal representation of a receive virtqueue */ 144 struct receive_queue { 145 /* Virtqueue associated with this receive_queue */ 146 struct virtqueue *vq; 147 148 struct napi_struct napi; 149 150 struct bpf_prog __rcu *xdp_prog; 151 152 struct virtnet_rq_stats stats; 153 154 /* Chain pages by the private ptr. */ 155 struct page *pages; 156 157 /* Average packet length for mergeable receive buffers. */ 158 struct ewma_pkt_len mrg_avg_pkt_len; 159 160 /* Page frag for packet buffer allocation. */ 161 struct page_frag alloc_frag; 162 163 /* RX: fragments + linear part + virtio header */ 164 struct scatterlist sg[MAX_SKB_FRAGS + 2]; 165 166 /* Min single buffer size for mergeable buffers case. */ 167 unsigned int min_buf_len; 168 169 /* Name of this receive queue: input.$index */ 170 char name[40]; 171 172 struct xdp_rxq_info xdp_rxq; 173 }; 174 175 /* This structure can contain rss message with maximum settings for indirection table and keysize 176 * Note, that default structure that describes RSS configuration virtio_net_rss_config 177 * contains same info but can't handle table values. 178 * In any case, structure would be passed to virtio hw through sg_buf split by parts 179 * because table sizes may be differ according to the device configuration. 180 */ 181 #define VIRTIO_NET_RSS_MAX_KEY_SIZE 40 182 #define VIRTIO_NET_RSS_MAX_TABLE_LEN 128 183 struct virtio_net_ctrl_rss { 184 u32 hash_types; 185 u16 indirection_table_mask; 186 u16 unclassified_queue; 187 u16 indirection_table[VIRTIO_NET_RSS_MAX_TABLE_LEN]; 188 u16 max_tx_vq; 189 u8 hash_key_length; 190 u8 key[VIRTIO_NET_RSS_MAX_KEY_SIZE]; 191 }; 192 193 /* Control VQ buffers: protected by the rtnl lock */ 194 struct control_buf { 195 struct virtio_net_ctrl_hdr hdr; 196 virtio_net_ctrl_ack status; 197 struct virtio_net_ctrl_mq mq; 198 u8 promisc; 199 u8 allmulti; 200 __virtio16 vid; 201 __virtio64 offloads; 202 struct virtio_net_ctrl_rss rss; 203 }; 204 205 struct virtnet_info { 206 struct virtio_device *vdev; 207 struct virtqueue *cvq; 208 struct net_device *dev; 209 struct send_queue *sq; 210 struct receive_queue *rq; 211 unsigned int status; 212 213 /* Max # of queue pairs supported by the device */ 214 u16 max_queue_pairs; 215 216 /* # of queue pairs currently used by the driver */ 217 u16 curr_queue_pairs; 218 219 /* # of XDP queue pairs currently used by the driver */ 220 u16 xdp_queue_pairs; 221 222 /* xdp_queue_pairs may be 0, when xdp is already loaded. So add this. */ 223 bool xdp_enabled; 224 225 /* I like... big packets and I cannot lie! */ 226 bool big_packets; 227 228 /* number of sg entries allocated for big packets */ 229 unsigned int big_packets_num_skbfrags; 230 231 /* Host will merge rx buffers for big packets (shake it! shake it!) */ 232 bool mergeable_rx_bufs; 233 234 /* Host supports rss and/or hash report */ 235 bool has_rss; 236 bool has_rss_hash_report; 237 u8 rss_key_size; 238 u16 rss_indir_table_size; 239 u32 rss_hash_types_supported; 240 u32 rss_hash_types_saved; 241 242 /* Has control virtqueue */ 243 bool has_cvq; 244 245 /* Host can handle any s/g split between our header and packet data */ 246 bool any_header_sg; 247 248 /* Packet virtio header size */ 249 u8 hdr_len; 250 251 /* Work struct for delayed refilling if we run low on memory. */ 252 struct delayed_work refill; 253 254 /* Is delayed refill enabled? */ 255 bool refill_enabled; 256 257 /* The lock to synchronize the access to refill_enabled */ 258 spinlock_t refill_lock; 259 260 /* Work struct for config space updates */ 261 struct work_struct config_work; 262 263 /* Does the affinity hint is set for virtqueues? */ 264 bool affinity_hint_set; 265 266 /* CPU hotplug instances for online & dead */ 267 struct hlist_node node; 268 struct hlist_node node_dead; 269 270 struct control_buf *ctrl; 271 272 /* Ethtool settings */ 273 u8 duplex; 274 u32 speed; 275 276 /* Interrupt coalescing settings */ 277 u32 tx_usecs; 278 u32 rx_usecs; 279 u32 tx_max_packets; 280 u32 rx_max_packets; 281 282 unsigned long guest_offloads; 283 unsigned long guest_offloads_capable; 284 285 /* failover when STANDBY feature enabled */ 286 struct failover *failover; 287 }; 288 289 struct padded_vnet_hdr { 290 struct virtio_net_hdr_v1_hash hdr; 291 /* 292 * hdr is in a separate sg buffer, and data sg buffer shares same page 293 * with this header sg. This padding makes next sg 16 byte aligned 294 * after the header. 295 */ 296 char padding[12]; 297 }; 298 299 static void virtnet_rq_free_unused_buf(struct virtqueue *vq, void *buf); 300 static void virtnet_sq_free_unused_buf(struct virtqueue *vq, void *buf); 301 302 static bool is_xdp_frame(void *ptr) 303 { 304 return (unsigned long)ptr & VIRTIO_XDP_FLAG; 305 } 306 307 static void *xdp_to_ptr(struct xdp_frame *ptr) 308 { 309 return (void *)((unsigned long)ptr | VIRTIO_XDP_FLAG); 310 } 311 312 static struct xdp_frame *ptr_to_xdp(void *ptr) 313 { 314 return (struct xdp_frame *)((unsigned long)ptr & ~VIRTIO_XDP_FLAG); 315 } 316 317 /* Converting between virtqueue no. and kernel tx/rx queue no. 318 * 0:rx0 1:tx0 2:rx1 3:tx1 ... 2N:rxN 2N+1:txN 2N+2:cvq 319 */ 320 static int vq2txq(struct virtqueue *vq) 321 { 322 return (vq->index - 1) / 2; 323 } 324 325 static int txq2vq(int txq) 326 { 327 return txq * 2 + 1; 328 } 329 330 static int vq2rxq(struct virtqueue *vq) 331 { 332 return vq->index / 2; 333 } 334 335 static int rxq2vq(int rxq) 336 { 337 return rxq * 2; 338 } 339 340 static inline struct virtio_net_hdr_mrg_rxbuf *skb_vnet_hdr(struct sk_buff *skb) 341 { 342 return (struct virtio_net_hdr_mrg_rxbuf *)skb->cb; 343 } 344 345 /* 346 * private is used to chain pages for big packets, put the whole 347 * most recent used list in the beginning for reuse 348 */ 349 static void give_pages(struct receive_queue *rq, struct page *page) 350 { 351 struct page *end; 352 353 /* Find end of list, sew whole thing into vi->rq.pages. */ 354 for (end = page; end->private; end = (struct page *)end->private); 355 end->private = (unsigned long)rq->pages; 356 rq->pages = page; 357 } 358 359 static struct page *get_a_page(struct receive_queue *rq, gfp_t gfp_mask) 360 { 361 struct page *p = rq->pages; 362 363 if (p) { 364 rq->pages = (struct page *)p->private; 365 /* clear private here, it is used to chain pages */ 366 p->private = 0; 367 } else 368 p = alloc_page(gfp_mask); 369 return p; 370 } 371 372 static void enable_delayed_refill(struct virtnet_info *vi) 373 { 374 spin_lock_bh(&vi->refill_lock); 375 vi->refill_enabled = true; 376 spin_unlock_bh(&vi->refill_lock); 377 } 378 379 static void disable_delayed_refill(struct virtnet_info *vi) 380 { 381 spin_lock_bh(&vi->refill_lock); 382 vi->refill_enabled = false; 383 spin_unlock_bh(&vi->refill_lock); 384 } 385 386 static void virtqueue_napi_schedule(struct napi_struct *napi, 387 struct virtqueue *vq) 388 { 389 if (napi_schedule_prep(napi)) { 390 virtqueue_disable_cb(vq); 391 __napi_schedule(napi); 392 } 393 } 394 395 static void virtqueue_napi_complete(struct napi_struct *napi, 396 struct virtqueue *vq, int processed) 397 { 398 int opaque; 399 400 opaque = virtqueue_enable_cb_prepare(vq); 401 if (napi_complete_done(napi, processed)) { 402 if (unlikely(virtqueue_poll(vq, opaque))) 403 virtqueue_napi_schedule(napi, vq); 404 } else { 405 virtqueue_disable_cb(vq); 406 } 407 } 408 409 static void skb_xmit_done(struct virtqueue *vq) 410 { 411 struct virtnet_info *vi = vq->vdev->priv; 412 struct napi_struct *napi = &vi->sq[vq2txq(vq)].napi; 413 414 /* Suppress further interrupts. */ 415 virtqueue_disable_cb(vq); 416 417 if (napi->weight) 418 virtqueue_napi_schedule(napi, vq); 419 else 420 /* We were probably waiting for more output buffers. */ 421 netif_wake_subqueue(vi->dev, vq2txq(vq)); 422 } 423 424 #define MRG_CTX_HEADER_SHIFT 22 425 static void *mergeable_len_to_ctx(unsigned int truesize, 426 unsigned int headroom) 427 { 428 return (void *)(unsigned long)((headroom << MRG_CTX_HEADER_SHIFT) | truesize); 429 } 430 431 static unsigned int mergeable_ctx_to_headroom(void *mrg_ctx) 432 { 433 return (unsigned long)mrg_ctx >> MRG_CTX_HEADER_SHIFT; 434 } 435 436 static unsigned int mergeable_ctx_to_truesize(void *mrg_ctx) 437 { 438 return (unsigned long)mrg_ctx & ((1 << MRG_CTX_HEADER_SHIFT) - 1); 439 } 440 441 /* Called from bottom half context */ 442 static struct sk_buff *page_to_skb(struct virtnet_info *vi, 443 struct receive_queue *rq, 444 struct page *page, unsigned int offset, 445 unsigned int len, unsigned int truesize, 446 bool hdr_valid, unsigned int metasize, 447 unsigned int headroom) 448 { 449 struct sk_buff *skb; 450 struct virtio_net_hdr_mrg_rxbuf *hdr; 451 unsigned int copy, hdr_len, hdr_padded_len; 452 struct page *page_to_free = NULL; 453 int tailroom, shinfo_size; 454 char *p, *hdr_p, *buf; 455 456 p = page_address(page) + offset; 457 hdr_p = p; 458 459 hdr_len = vi->hdr_len; 460 if (vi->mergeable_rx_bufs) 461 hdr_padded_len = hdr_len; 462 else 463 hdr_padded_len = sizeof(struct padded_vnet_hdr); 464 465 /* If headroom is not 0, there is an offset between the beginning of the 466 * data and the allocated space, otherwise the data and the allocated 467 * space are aligned. 468 * 469 * Buffers with headroom use PAGE_SIZE as alloc size, see 470 * add_recvbuf_mergeable() + get_mergeable_buf_len() 471 */ 472 truesize = headroom ? PAGE_SIZE : truesize; 473 tailroom = truesize - headroom; 474 buf = p - headroom; 475 476 len -= hdr_len; 477 offset += hdr_padded_len; 478 p += hdr_padded_len; 479 tailroom -= hdr_padded_len + len; 480 481 shinfo_size = SKB_DATA_ALIGN(sizeof(struct skb_shared_info)); 482 483 /* copy small packet so we can reuse these pages */ 484 if (!NET_IP_ALIGN && len > GOOD_COPY_LEN && tailroom >= shinfo_size) { 485 skb = build_skb(buf, truesize); 486 if (unlikely(!skb)) 487 return NULL; 488 489 skb_reserve(skb, p - buf); 490 skb_put(skb, len); 491 492 page = (struct page *)page->private; 493 if (page) 494 give_pages(rq, page); 495 goto ok; 496 } 497 498 /* copy small packet so we can reuse these pages for small data */ 499 skb = napi_alloc_skb(&rq->napi, GOOD_COPY_LEN); 500 if (unlikely(!skb)) 501 return NULL; 502 503 /* Copy all frame if it fits skb->head, otherwise 504 * we let virtio_net_hdr_to_skb() and GRO pull headers as needed. 505 */ 506 if (len <= skb_tailroom(skb)) 507 copy = len; 508 else 509 copy = ETH_HLEN + metasize; 510 skb_put_data(skb, p, copy); 511 512 len -= copy; 513 offset += copy; 514 515 if (vi->mergeable_rx_bufs) { 516 if (len) 517 skb_add_rx_frag(skb, 0, page, offset, len, truesize); 518 else 519 page_to_free = page; 520 goto ok; 521 } 522 523 /* 524 * Verify that we can indeed put this data into a skb. 525 * This is here to handle cases when the device erroneously 526 * tries to receive more than is possible. This is usually 527 * the case of a broken device. 528 */ 529 if (unlikely(len > MAX_SKB_FRAGS * PAGE_SIZE)) { 530 net_dbg_ratelimited("%s: too much data\n", skb->dev->name); 531 dev_kfree_skb(skb); 532 return NULL; 533 } 534 BUG_ON(offset >= PAGE_SIZE); 535 while (len) { 536 unsigned int frag_size = min((unsigned)PAGE_SIZE - offset, len); 537 skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags, page, offset, 538 frag_size, truesize); 539 len -= frag_size; 540 page = (struct page *)page->private; 541 offset = 0; 542 } 543 544 if (page) 545 give_pages(rq, page); 546 547 ok: 548 /* hdr_valid means no XDP, so we can copy the vnet header */ 549 if (hdr_valid) { 550 hdr = skb_vnet_hdr(skb); 551 memcpy(hdr, hdr_p, hdr_len); 552 } 553 if (page_to_free) 554 put_page(page_to_free); 555 556 if (metasize) { 557 __skb_pull(skb, metasize); 558 skb_metadata_set(skb, metasize); 559 } 560 561 return skb; 562 } 563 564 static int __virtnet_xdp_xmit_one(struct virtnet_info *vi, 565 struct send_queue *sq, 566 struct xdp_frame *xdpf) 567 { 568 struct virtio_net_hdr_mrg_rxbuf *hdr; 569 int err; 570 571 if (unlikely(xdpf->headroom < vi->hdr_len)) 572 return -EOVERFLOW; 573 574 /* Make room for virtqueue hdr (also change xdpf->headroom?) */ 575 xdpf->data -= vi->hdr_len; 576 /* Zero header and leave csum up to XDP layers */ 577 hdr = xdpf->data; 578 memset(hdr, 0, vi->hdr_len); 579 xdpf->len += vi->hdr_len; 580 581 sg_init_one(sq->sg, xdpf->data, xdpf->len); 582 583 err = virtqueue_add_outbuf(sq->vq, sq->sg, 1, xdp_to_ptr(xdpf), 584 GFP_ATOMIC); 585 if (unlikely(err)) 586 return -ENOSPC; /* Caller handle free/refcnt */ 587 588 return 0; 589 } 590 591 /* when vi->curr_queue_pairs > nr_cpu_ids, the txq/sq is only used for xdp tx on 592 * the current cpu, so it does not need to be locked. 593 * 594 * Here we use marco instead of inline functions because we have to deal with 595 * three issues at the same time: 1. the choice of sq. 2. judge and execute the 596 * lock/unlock of txq 3. make sparse happy. It is difficult for two inline 597 * functions to perfectly solve these three problems at the same time. 598 */ 599 #define virtnet_xdp_get_sq(vi) ({ \ 600 int cpu = smp_processor_id(); \ 601 struct netdev_queue *txq; \ 602 typeof(vi) v = (vi); \ 603 unsigned int qp; \ 604 \ 605 if (v->curr_queue_pairs > nr_cpu_ids) { \ 606 qp = v->curr_queue_pairs - v->xdp_queue_pairs; \ 607 qp += cpu; \ 608 txq = netdev_get_tx_queue(v->dev, qp); \ 609 __netif_tx_acquire(txq); \ 610 } else { \ 611 qp = cpu % v->curr_queue_pairs; \ 612 txq = netdev_get_tx_queue(v->dev, qp); \ 613 __netif_tx_lock(txq, cpu); \ 614 } \ 615 v->sq + qp; \ 616 }) 617 618 #define virtnet_xdp_put_sq(vi, q) { \ 619 struct netdev_queue *txq; \ 620 typeof(vi) v = (vi); \ 621 \ 622 txq = netdev_get_tx_queue(v->dev, (q) - v->sq); \ 623 if (v->curr_queue_pairs > nr_cpu_ids) \ 624 __netif_tx_release(txq); \ 625 else \ 626 __netif_tx_unlock(txq); \ 627 } 628 629 static int virtnet_xdp_xmit(struct net_device *dev, 630 int n, struct xdp_frame **frames, u32 flags) 631 { 632 struct virtnet_info *vi = netdev_priv(dev); 633 struct receive_queue *rq = vi->rq; 634 struct bpf_prog *xdp_prog; 635 struct send_queue *sq; 636 unsigned int len; 637 int packets = 0; 638 int bytes = 0; 639 int nxmit = 0; 640 int kicks = 0; 641 void *ptr; 642 int ret; 643 int i; 644 645 /* Only allow ndo_xdp_xmit if XDP is loaded on dev, as this 646 * indicate XDP resources have been successfully allocated. 647 */ 648 xdp_prog = rcu_access_pointer(rq->xdp_prog); 649 if (!xdp_prog) 650 return -ENXIO; 651 652 sq = virtnet_xdp_get_sq(vi); 653 654 if (unlikely(flags & ~XDP_XMIT_FLAGS_MASK)) { 655 ret = -EINVAL; 656 goto out; 657 } 658 659 /* Free up any pending old buffers before queueing new ones. */ 660 while ((ptr = virtqueue_get_buf(sq->vq, &len)) != NULL) { 661 if (likely(is_xdp_frame(ptr))) { 662 struct xdp_frame *frame = ptr_to_xdp(ptr); 663 664 bytes += frame->len; 665 xdp_return_frame(frame); 666 } else { 667 struct sk_buff *skb = ptr; 668 669 bytes += skb->len; 670 napi_consume_skb(skb, false); 671 } 672 packets++; 673 } 674 675 for (i = 0; i < n; i++) { 676 struct xdp_frame *xdpf = frames[i]; 677 678 if (__virtnet_xdp_xmit_one(vi, sq, xdpf)) 679 break; 680 nxmit++; 681 } 682 ret = nxmit; 683 684 if (flags & XDP_XMIT_FLUSH) { 685 if (virtqueue_kick_prepare(sq->vq) && virtqueue_notify(sq->vq)) 686 kicks = 1; 687 } 688 out: 689 u64_stats_update_begin(&sq->stats.syncp); 690 sq->stats.bytes += bytes; 691 sq->stats.packets += packets; 692 sq->stats.xdp_tx += n; 693 sq->stats.xdp_tx_drops += n - nxmit; 694 sq->stats.kicks += kicks; 695 u64_stats_update_end(&sq->stats.syncp); 696 697 virtnet_xdp_put_sq(vi, sq); 698 return ret; 699 } 700 701 static unsigned int virtnet_get_headroom(struct virtnet_info *vi) 702 { 703 return vi->xdp_enabled ? VIRTIO_XDP_HEADROOM : 0; 704 } 705 706 /* We copy the packet for XDP in the following cases: 707 * 708 * 1) Packet is scattered across multiple rx buffers. 709 * 2) Headroom space is insufficient. 710 * 711 * This is inefficient but it's a temporary condition that 712 * we hit right after XDP is enabled and until queue is refilled 713 * with large buffers with sufficient headroom - so it should affect 714 * at most queue size packets. 715 * Afterwards, the conditions to enable 716 * XDP should preclude the underlying device from sending packets 717 * across multiple buffers (num_buf > 1), and we make sure buffers 718 * have enough headroom. 719 */ 720 static struct page *xdp_linearize_page(struct receive_queue *rq, 721 u16 *num_buf, 722 struct page *p, 723 int offset, 724 int page_off, 725 unsigned int *len) 726 { 727 struct page *page = alloc_page(GFP_ATOMIC); 728 729 if (!page) 730 return NULL; 731 732 memcpy(page_address(page) + page_off, page_address(p) + offset, *len); 733 page_off += *len; 734 735 while (--*num_buf) { 736 int tailroom = SKB_DATA_ALIGN(sizeof(struct skb_shared_info)); 737 unsigned int buflen; 738 void *buf; 739 int off; 740 741 buf = virtqueue_get_buf(rq->vq, &buflen); 742 if (unlikely(!buf)) 743 goto err_buf; 744 745 p = virt_to_head_page(buf); 746 off = buf - page_address(p); 747 748 /* guard against a misconfigured or uncooperative backend that 749 * is sending packet larger than the MTU. 750 */ 751 if ((page_off + buflen + tailroom) > PAGE_SIZE) { 752 put_page(p); 753 goto err_buf; 754 } 755 756 memcpy(page_address(page) + page_off, 757 page_address(p) + off, buflen); 758 page_off += buflen; 759 put_page(p); 760 } 761 762 /* Headroom does not contribute to packet length */ 763 *len = page_off - VIRTIO_XDP_HEADROOM; 764 return page; 765 err_buf: 766 __free_pages(page, 0); 767 return NULL; 768 } 769 770 static struct sk_buff *receive_small(struct net_device *dev, 771 struct virtnet_info *vi, 772 struct receive_queue *rq, 773 void *buf, void *ctx, 774 unsigned int len, 775 unsigned int *xdp_xmit, 776 struct virtnet_rq_stats *stats) 777 { 778 struct sk_buff *skb; 779 struct bpf_prog *xdp_prog; 780 unsigned int xdp_headroom = (unsigned long)ctx; 781 unsigned int header_offset = VIRTNET_RX_PAD + xdp_headroom; 782 unsigned int headroom = vi->hdr_len + header_offset; 783 unsigned int buflen = SKB_DATA_ALIGN(GOOD_PACKET_LEN + headroom) + 784 SKB_DATA_ALIGN(sizeof(struct skb_shared_info)); 785 struct page *page = virt_to_head_page(buf); 786 unsigned int delta = 0; 787 struct page *xdp_page; 788 int err; 789 unsigned int metasize = 0; 790 791 len -= vi->hdr_len; 792 stats->bytes += len; 793 794 if (unlikely(len > GOOD_PACKET_LEN)) { 795 pr_debug("%s: rx error: len %u exceeds max size %d\n", 796 dev->name, len, GOOD_PACKET_LEN); 797 dev->stats.rx_length_errors++; 798 goto err; 799 } 800 801 if (likely(!vi->xdp_enabled)) { 802 xdp_prog = NULL; 803 goto skip_xdp; 804 } 805 806 rcu_read_lock(); 807 xdp_prog = rcu_dereference(rq->xdp_prog); 808 if (xdp_prog) { 809 struct virtio_net_hdr_mrg_rxbuf *hdr = buf + header_offset; 810 struct xdp_frame *xdpf; 811 struct xdp_buff xdp; 812 void *orig_data; 813 u32 act; 814 815 if (unlikely(hdr->hdr.gso_type)) 816 goto err_xdp; 817 818 if (unlikely(xdp_headroom < virtnet_get_headroom(vi))) { 819 int offset = buf - page_address(page) + header_offset; 820 unsigned int tlen = len + vi->hdr_len; 821 u16 num_buf = 1; 822 823 xdp_headroom = virtnet_get_headroom(vi); 824 header_offset = VIRTNET_RX_PAD + xdp_headroom; 825 headroom = vi->hdr_len + header_offset; 826 buflen = SKB_DATA_ALIGN(GOOD_PACKET_LEN + headroom) + 827 SKB_DATA_ALIGN(sizeof(struct skb_shared_info)); 828 xdp_page = xdp_linearize_page(rq, &num_buf, page, 829 offset, header_offset, 830 &tlen); 831 if (!xdp_page) 832 goto err_xdp; 833 834 buf = page_address(xdp_page); 835 put_page(page); 836 page = xdp_page; 837 } 838 839 xdp_init_buff(&xdp, buflen, &rq->xdp_rxq); 840 xdp_prepare_buff(&xdp, buf + VIRTNET_RX_PAD + vi->hdr_len, 841 xdp_headroom, len, true); 842 orig_data = xdp.data; 843 act = bpf_prog_run_xdp(xdp_prog, &xdp); 844 stats->xdp_packets++; 845 846 switch (act) { 847 case XDP_PASS: 848 /* Recalculate length in case bpf program changed it */ 849 delta = orig_data - xdp.data; 850 len = xdp.data_end - xdp.data; 851 metasize = xdp.data - xdp.data_meta; 852 break; 853 case XDP_TX: 854 stats->xdp_tx++; 855 xdpf = xdp_convert_buff_to_frame(&xdp); 856 if (unlikely(!xdpf)) 857 goto err_xdp; 858 err = virtnet_xdp_xmit(dev, 1, &xdpf, 0); 859 if (unlikely(!err)) { 860 xdp_return_frame_rx_napi(xdpf); 861 } else if (unlikely(err < 0)) { 862 trace_xdp_exception(vi->dev, xdp_prog, act); 863 goto err_xdp; 864 } 865 *xdp_xmit |= VIRTIO_XDP_TX; 866 rcu_read_unlock(); 867 goto xdp_xmit; 868 case XDP_REDIRECT: 869 stats->xdp_redirects++; 870 err = xdp_do_redirect(dev, &xdp, xdp_prog); 871 if (err) 872 goto err_xdp; 873 *xdp_xmit |= VIRTIO_XDP_REDIR; 874 rcu_read_unlock(); 875 goto xdp_xmit; 876 default: 877 bpf_warn_invalid_xdp_action(vi->dev, xdp_prog, act); 878 fallthrough; 879 case XDP_ABORTED: 880 trace_xdp_exception(vi->dev, xdp_prog, act); 881 goto err_xdp; 882 case XDP_DROP: 883 goto err_xdp; 884 } 885 } 886 rcu_read_unlock(); 887 888 skip_xdp: 889 skb = build_skb(buf, buflen); 890 if (!skb) 891 goto err; 892 skb_reserve(skb, headroom - delta); 893 skb_put(skb, len); 894 if (!xdp_prog) { 895 buf += header_offset; 896 memcpy(skb_vnet_hdr(skb), buf, vi->hdr_len); 897 } /* keep zeroed vnet hdr since XDP is loaded */ 898 899 if (metasize) 900 skb_metadata_set(skb, metasize); 901 902 return skb; 903 904 err_xdp: 905 rcu_read_unlock(); 906 stats->xdp_drops++; 907 err: 908 stats->drops++; 909 put_page(page); 910 xdp_xmit: 911 return NULL; 912 } 913 914 static struct sk_buff *receive_big(struct net_device *dev, 915 struct virtnet_info *vi, 916 struct receive_queue *rq, 917 void *buf, 918 unsigned int len, 919 struct virtnet_rq_stats *stats) 920 { 921 struct page *page = buf; 922 struct sk_buff *skb = 923 page_to_skb(vi, rq, page, 0, len, PAGE_SIZE, true, 0, 0); 924 925 stats->bytes += len - vi->hdr_len; 926 if (unlikely(!skb)) 927 goto err; 928 929 return skb; 930 931 err: 932 stats->drops++; 933 give_pages(rq, page); 934 return NULL; 935 } 936 937 static struct sk_buff *receive_mergeable(struct net_device *dev, 938 struct virtnet_info *vi, 939 struct receive_queue *rq, 940 void *buf, 941 void *ctx, 942 unsigned int len, 943 unsigned int *xdp_xmit, 944 struct virtnet_rq_stats *stats) 945 { 946 struct virtio_net_hdr_mrg_rxbuf *hdr = buf; 947 u16 num_buf = virtio16_to_cpu(vi->vdev, hdr->num_buffers); 948 struct page *page = virt_to_head_page(buf); 949 int offset = buf - page_address(page); 950 struct sk_buff *head_skb, *curr_skb; 951 struct bpf_prog *xdp_prog; 952 unsigned int truesize = mergeable_ctx_to_truesize(ctx); 953 unsigned int headroom = mergeable_ctx_to_headroom(ctx); 954 unsigned int metasize = 0; 955 unsigned int frame_sz; 956 int err; 957 958 head_skb = NULL; 959 stats->bytes += len - vi->hdr_len; 960 961 if (unlikely(len > truesize)) { 962 pr_debug("%s: rx error: len %u exceeds truesize %lu\n", 963 dev->name, len, (unsigned long)ctx); 964 dev->stats.rx_length_errors++; 965 goto err_skb; 966 } 967 968 if (likely(!vi->xdp_enabled)) { 969 xdp_prog = NULL; 970 goto skip_xdp; 971 } 972 973 rcu_read_lock(); 974 xdp_prog = rcu_dereference(rq->xdp_prog); 975 if (xdp_prog) { 976 struct xdp_frame *xdpf; 977 struct page *xdp_page; 978 struct xdp_buff xdp; 979 void *data; 980 u32 act; 981 982 /* Transient failure which in theory could occur if 983 * in-flight packets from before XDP was enabled reach 984 * the receive path after XDP is loaded. 985 */ 986 if (unlikely(hdr->hdr.gso_type)) 987 goto err_xdp; 988 989 /* Buffers with headroom use PAGE_SIZE as alloc size, 990 * see add_recvbuf_mergeable() + get_mergeable_buf_len() 991 */ 992 frame_sz = headroom ? PAGE_SIZE : truesize; 993 994 /* This happens when rx buffer size is underestimated 995 * or headroom is not enough because of the buffer 996 * was refilled before XDP is set. This should only 997 * happen for the first several packets, so we don't 998 * care much about its performance. 999 */ 1000 if (unlikely(num_buf > 1 || 1001 headroom < virtnet_get_headroom(vi))) { 1002 /* linearize data for XDP */ 1003 xdp_page = xdp_linearize_page(rq, &num_buf, 1004 page, offset, 1005 VIRTIO_XDP_HEADROOM, 1006 &len); 1007 frame_sz = PAGE_SIZE; 1008 1009 if (!xdp_page) 1010 goto err_xdp; 1011 offset = VIRTIO_XDP_HEADROOM; 1012 } else { 1013 xdp_page = page; 1014 } 1015 1016 /* Allow consuming headroom but reserve enough space to push 1017 * the descriptor on if we get an XDP_TX return code. 1018 */ 1019 data = page_address(xdp_page) + offset; 1020 xdp_init_buff(&xdp, frame_sz - vi->hdr_len, &rq->xdp_rxq); 1021 xdp_prepare_buff(&xdp, data - VIRTIO_XDP_HEADROOM + vi->hdr_len, 1022 VIRTIO_XDP_HEADROOM, len - vi->hdr_len, true); 1023 1024 act = bpf_prog_run_xdp(xdp_prog, &xdp); 1025 stats->xdp_packets++; 1026 1027 switch (act) { 1028 case XDP_PASS: 1029 metasize = xdp.data - xdp.data_meta; 1030 1031 /* recalculate offset to account for any header 1032 * adjustments and minus the metasize to copy the 1033 * metadata in page_to_skb(). Note other cases do not 1034 * build an skb and avoid using offset 1035 */ 1036 offset = xdp.data - page_address(xdp_page) - 1037 vi->hdr_len - metasize; 1038 1039 /* recalculate len if xdp.data, xdp.data_end or 1040 * xdp.data_meta were adjusted 1041 */ 1042 len = xdp.data_end - xdp.data + vi->hdr_len + metasize; 1043 1044 /* recalculate headroom if xdp.data or xdp_data_meta 1045 * were adjusted, note that offset should always point 1046 * to the start of the reserved bytes for virtio_net 1047 * header which are followed by xdp.data, that means 1048 * that offset is equal to the headroom (when buf is 1049 * starting at the beginning of the page, otherwise 1050 * there is a base offset inside the page) but it's used 1051 * with a different starting point (buf start) than 1052 * xdp.data (buf start + vnet hdr size). If xdp.data or 1053 * data_meta were adjusted by the xdp prog then the 1054 * headroom size has changed and so has the offset, we 1055 * can use data_hard_start, which points at buf start + 1056 * vnet hdr size, to calculate the new headroom and use 1057 * it later to compute buf start in page_to_skb() 1058 */ 1059 headroom = xdp.data - xdp.data_hard_start - metasize; 1060 1061 /* We can only create skb based on xdp_page. */ 1062 if (unlikely(xdp_page != page)) { 1063 rcu_read_unlock(); 1064 put_page(page); 1065 head_skb = page_to_skb(vi, rq, xdp_page, offset, 1066 len, PAGE_SIZE, false, 1067 metasize, 1068 headroom); 1069 return head_skb; 1070 } 1071 break; 1072 case XDP_TX: 1073 stats->xdp_tx++; 1074 xdpf = xdp_convert_buff_to_frame(&xdp); 1075 if (unlikely(!xdpf)) { 1076 if (unlikely(xdp_page != page)) 1077 put_page(xdp_page); 1078 goto err_xdp; 1079 } 1080 err = virtnet_xdp_xmit(dev, 1, &xdpf, 0); 1081 if (unlikely(!err)) { 1082 xdp_return_frame_rx_napi(xdpf); 1083 } else if (unlikely(err < 0)) { 1084 trace_xdp_exception(vi->dev, xdp_prog, act); 1085 if (unlikely(xdp_page != page)) 1086 put_page(xdp_page); 1087 goto err_xdp; 1088 } 1089 *xdp_xmit |= VIRTIO_XDP_TX; 1090 if (unlikely(xdp_page != page)) 1091 put_page(page); 1092 rcu_read_unlock(); 1093 goto xdp_xmit; 1094 case XDP_REDIRECT: 1095 stats->xdp_redirects++; 1096 err = xdp_do_redirect(dev, &xdp, xdp_prog); 1097 if (err) { 1098 if (unlikely(xdp_page != page)) 1099 put_page(xdp_page); 1100 goto err_xdp; 1101 } 1102 *xdp_xmit |= VIRTIO_XDP_REDIR; 1103 if (unlikely(xdp_page != page)) 1104 put_page(page); 1105 rcu_read_unlock(); 1106 goto xdp_xmit; 1107 default: 1108 bpf_warn_invalid_xdp_action(vi->dev, xdp_prog, act); 1109 fallthrough; 1110 case XDP_ABORTED: 1111 trace_xdp_exception(vi->dev, xdp_prog, act); 1112 fallthrough; 1113 case XDP_DROP: 1114 if (unlikely(xdp_page != page)) 1115 __free_pages(xdp_page, 0); 1116 goto err_xdp; 1117 } 1118 } 1119 rcu_read_unlock(); 1120 1121 skip_xdp: 1122 head_skb = page_to_skb(vi, rq, page, offset, len, truesize, !xdp_prog, 1123 metasize, headroom); 1124 curr_skb = head_skb; 1125 1126 if (unlikely(!curr_skb)) 1127 goto err_skb; 1128 while (--num_buf) { 1129 int num_skb_frags; 1130 1131 buf = virtqueue_get_buf_ctx(rq->vq, &len, &ctx); 1132 if (unlikely(!buf)) { 1133 pr_debug("%s: rx error: %d buffers out of %d missing\n", 1134 dev->name, num_buf, 1135 virtio16_to_cpu(vi->vdev, 1136 hdr->num_buffers)); 1137 dev->stats.rx_length_errors++; 1138 goto err_buf; 1139 } 1140 1141 stats->bytes += len; 1142 page = virt_to_head_page(buf); 1143 1144 truesize = mergeable_ctx_to_truesize(ctx); 1145 if (unlikely(len > truesize)) { 1146 pr_debug("%s: rx error: len %u exceeds truesize %lu\n", 1147 dev->name, len, (unsigned long)ctx); 1148 dev->stats.rx_length_errors++; 1149 goto err_skb; 1150 } 1151 1152 num_skb_frags = skb_shinfo(curr_skb)->nr_frags; 1153 if (unlikely(num_skb_frags == MAX_SKB_FRAGS)) { 1154 struct sk_buff *nskb = alloc_skb(0, GFP_ATOMIC); 1155 1156 if (unlikely(!nskb)) 1157 goto err_skb; 1158 if (curr_skb == head_skb) 1159 skb_shinfo(curr_skb)->frag_list = nskb; 1160 else 1161 curr_skb->next = nskb; 1162 curr_skb = nskb; 1163 head_skb->truesize += nskb->truesize; 1164 num_skb_frags = 0; 1165 } 1166 if (curr_skb != head_skb) { 1167 head_skb->data_len += len; 1168 head_skb->len += len; 1169 head_skb->truesize += truesize; 1170 } 1171 offset = buf - page_address(page); 1172 if (skb_can_coalesce(curr_skb, num_skb_frags, page, offset)) { 1173 put_page(page); 1174 skb_coalesce_rx_frag(curr_skb, num_skb_frags - 1, 1175 len, truesize); 1176 } else { 1177 skb_add_rx_frag(curr_skb, num_skb_frags, page, 1178 offset, len, truesize); 1179 } 1180 } 1181 1182 ewma_pkt_len_add(&rq->mrg_avg_pkt_len, head_skb->len); 1183 return head_skb; 1184 1185 err_xdp: 1186 rcu_read_unlock(); 1187 stats->xdp_drops++; 1188 err_skb: 1189 put_page(page); 1190 while (num_buf-- > 1) { 1191 buf = virtqueue_get_buf(rq->vq, &len); 1192 if (unlikely(!buf)) { 1193 pr_debug("%s: rx error: %d buffers missing\n", 1194 dev->name, num_buf); 1195 dev->stats.rx_length_errors++; 1196 break; 1197 } 1198 stats->bytes += len; 1199 page = virt_to_head_page(buf); 1200 put_page(page); 1201 } 1202 err_buf: 1203 stats->drops++; 1204 dev_kfree_skb(head_skb); 1205 xdp_xmit: 1206 return NULL; 1207 } 1208 1209 static void virtio_skb_set_hash(const struct virtio_net_hdr_v1_hash *hdr_hash, 1210 struct sk_buff *skb) 1211 { 1212 enum pkt_hash_types rss_hash_type; 1213 1214 if (!hdr_hash || !skb) 1215 return; 1216 1217 switch (__le16_to_cpu(hdr_hash->hash_report)) { 1218 case VIRTIO_NET_HASH_REPORT_TCPv4: 1219 case VIRTIO_NET_HASH_REPORT_UDPv4: 1220 case VIRTIO_NET_HASH_REPORT_TCPv6: 1221 case VIRTIO_NET_HASH_REPORT_UDPv6: 1222 case VIRTIO_NET_HASH_REPORT_TCPv6_EX: 1223 case VIRTIO_NET_HASH_REPORT_UDPv6_EX: 1224 rss_hash_type = PKT_HASH_TYPE_L4; 1225 break; 1226 case VIRTIO_NET_HASH_REPORT_IPv4: 1227 case VIRTIO_NET_HASH_REPORT_IPv6: 1228 case VIRTIO_NET_HASH_REPORT_IPv6_EX: 1229 rss_hash_type = PKT_HASH_TYPE_L3; 1230 break; 1231 case VIRTIO_NET_HASH_REPORT_NONE: 1232 default: 1233 rss_hash_type = PKT_HASH_TYPE_NONE; 1234 } 1235 skb_set_hash(skb, __le32_to_cpu(hdr_hash->hash_value), rss_hash_type); 1236 } 1237 1238 static void receive_buf(struct virtnet_info *vi, struct receive_queue *rq, 1239 void *buf, unsigned int len, void **ctx, 1240 unsigned int *xdp_xmit, 1241 struct virtnet_rq_stats *stats) 1242 { 1243 struct net_device *dev = vi->dev; 1244 struct sk_buff *skb; 1245 struct virtio_net_hdr_mrg_rxbuf *hdr; 1246 1247 if (unlikely(len < vi->hdr_len + ETH_HLEN)) { 1248 pr_debug("%s: short packet %i\n", dev->name, len); 1249 dev->stats.rx_length_errors++; 1250 if (vi->mergeable_rx_bufs) { 1251 put_page(virt_to_head_page(buf)); 1252 } else if (vi->big_packets) { 1253 give_pages(rq, buf); 1254 } else { 1255 put_page(virt_to_head_page(buf)); 1256 } 1257 return; 1258 } 1259 1260 if (vi->mergeable_rx_bufs) 1261 skb = receive_mergeable(dev, vi, rq, buf, ctx, len, xdp_xmit, 1262 stats); 1263 else if (vi->big_packets) 1264 skb = receive_big(dev, vi, rq, buf, len, stats); 1265 else 1266 skb = receive_small(dev, vi, rq, buf, ctx, len, xdp_xmit, stats); 1267 1268 if (unlikely(!skb)) 1269 return; 1270 1271 hdr = skb_vnet_hdr(skb); 1272 if (dev->features & NETIF_F_RXHASH && vi->has_rss_hash_report) 1273 virtio_skb_set_hash((const struct virtio_net_hdr_v1_hash *)hdr, skb); 1274 1275 if (hdr->hdr.flags & VIRTIO_NET_HDR_F_DATA_VALID) 1276 skb->ip_summed = CHECKSUM_UNNECESSARY; 1277 1278 if (virtio_net_hdr_to_skb(skb, &hdr->hdr, 1279 virtio_is_little_endian(vi->vdev))) { 1280 net_warn_ratelimited("%s: bad gso: type: %u, size: %u\n", 1281 dev->name, hdr->hdr.gso_type, 1282 hdr->hdr.gso_size); 1283 goto frame_err; 1284 } 1285 1286 skb_record_rx_queue(skb, vq2rxq(rq->vq)); 1287 skb->protocol = eth_type_trans(skb, dev); 1288 pr_debug("Receiving skb proto 0x%04x len %i type %i\n", 1289 ntohs(skb->protocol), skb->len, skb->pkt_type); 1290 1291 napi_gro_receive(&rq->napi, skb); 1292 return; 1293 1294 frame_err: 1295 dev->stats.rx_frame_errors++; 1296 dev_kfree_skb(skb); 1297 } 1298 1299 /* Unlike mergeable buffers, all buffers are allocated to the 1300 * same size, except for the headroom. For this reason we do 1301 * not need to use mergeable_len_to_ctx here - it is enough 1302 * to store the headroom as the context ignoring the truesize. 1303 */ 1304 static int add_recvbuf_small(struct virtnet_info *vi, struct receive_queue *rq, 1305 gfp_t gfp) 1306 { 1307 struct page_frag *alloc_frag = &rq->alloc_frag; 1308 char *buf; 1309 unsigned int xdp_headroom = virtnet_get_headroom(vi); 1310 void *ctx = (void *)(unsigned long)xdp_headroom; 1311 int len = vi->hdr_len + VIRTNET_RX_PAD + GOOD_PACKET_LEN + xdp_headroom; 1312 int err; 1313 1314 len = SKB_DATA_ALIGN(len) + 1315 SKB_DATA_ALIGN(sizeof(struct skb_shared_info)); 1316 if (unlikely(!skb_page_frag_refill(len, alloc_frag, gfp))) 1317 return -ENOMEM; 1318 1319 buf = (char *)page_address(alloc_frag->page) + alloc_frag->offset; 1320 get_page(alloc_frag->page); 1321 alloc_frag->offset += len; 1322 sg_init_one(rq->sg, buf + VIRTNET_RX_PAD + xdp_headroom, 1323 vi->hdr_len + GOOD_PACKET_LEN); 1324 err = virtqueue_add_inbuf_ctx(rq->vq, rq->sg, 1, buf, ctx, gfp); 1325 if (err < 0) 1326 put_page(virt_to_head_page(buf)); 1327 return err; 1328 } 1329 1330 static int add_recvbuf_big(struct virtnet_info *vi, struct receive_queue *rq, 1331 gfp_t gfp) 1332 { 1333 struct page *first, *list = NULL; 1334 char *p; 1335 int i, err, offset; 1336 1337 sg_init_table(rq->sg, vi->big_packets_num_skbfrags + 2); 1338 1339 /* page in rq->sg[vi->big_packets_num_skbfrags + 1] is list tail */ 1340 for (i = vi->big_packets_num_skbfrags + 1; i > 1; --i) { 1341 first = get_a_page(rq, gfp); 1342 if (!first) { 1343 if (list) 1344 give_pages(rq, list); 1345 return -ENOMEM; 1346 } 1347 sg_set_buf(&rq->sg[i], page_address(first), PAGE_SIZE); 1348 1349 /* chain new page in list head to match sg */ 1350 first->private = (unsigned long)list; 1351 list = first; 1352 } 1353 1354 first = get_a_page(rq, gfp); 1355 if (!first) { 1356 give_pages(rq, list); 1357 return -ENOMEM; 1358 } 1359 p = page_address(first); 1360 1361 /* rq->sg[0], rq->sg[1] share the same page */ 1362 /* a separated rq->sg[0] for header - required in case !any_header_sg */ 1363 sg_set_buf(&rq->sg[0], p, vi->hdr_len); 1364 1365 /* rq->sg[1] for data packet, from offset */ 1366 offset = sizeof(struct padded_vnet_hdr); 1367 sg_set_buf(&rq->sg[1], p + offset, PAGE_SIZE - offset); 1368 1369 /* chain first in list head */ 1370 first->private = (unsigned long)list; 1371 err = virtqueue_add_inbuf(rq->vq, rq->sg, vi->big_packets_num_skbfrags + 2, 1372 first, gfp); 1373 if (err < 0) 1374 give_pages(rq, first); 1375 1376 return err; 1377 } 1378 1379 static unsigned int get_mergeable_buf_len(struct receive_queue *rq, 1380 struct ewma_pkt_len *avg_pkt_len, 1381 unsigned int room) 1382 { 1383 struct virtnet_info *vi = rq->vq->vdev->priv; 1384 const size_t hdr_len = vi->hdr_len; 1385 unsigned int len; 1386 1387 if (room) 1388 return PAGE_SIZE - room; 1389 1390 len = hdr_len + clamp_t(unsigned int, ewma_pkt_len_read(avg_pkt_len), 1391 rq->min_buf_len, PAGE_SIZE - hdr_len); 1392 1393 return ALIGN(len, L1_CACHE_BYTES); 1394 } 1395 1396 static int add_recvbuf_mergeable(struct virtnet_info *vi, 1397 struct receive_queue *rq, gfp_t gfp) 1398 { 1399 struct page_frag *alloc_frag = &rq->alloc_frag; 1400 unsigned int headroom = virtnet_get_headroom(vi); 1401 unsigned int tailroom = headroom ? sizeof(struct skb_shared_info) : 0; 1402 unsigned int room = SKB_DATA_ALIGN(headroom + tailroom); 1403 char *buf; 1404 void *ctx; 1405 int err; 1406 unsigned int len, hole; 1407 1408 /* Extra tailroom is needed to satisfy XDP's assumption. This 1409 * means rx frags coalescing won't work, but consider we've 1410 * disabled GSO for XDP, it won't be a big issue. 1411 */ 1412 len = get_mergeable_buf_len(rq, &rq->mrg_avg_pkt_len, room); 1413 if (unlikely(!skb_page_frag_refill(len + room, alloc_frag, gfp))) 1414 return -ENOMEM; 1415 1416 buf = (char *)page_address(alloc_frag->page) + alloc_frag->offset; 1417 buf += headroom; /* advance address leaving hole at front of pkt */ 1418 get_page(alloc_frag->page); 1419 alloc_frag->offset += len + room; 1420 hole = alloc_frag->size - alloc_frag->offset; 1421 if (hole < len + room) { 1422 /* To avoid internal fragmentation, if there is very likely not 1423 * enough space for another buffer, add the remaining space to 1424 * the current buffer. 1425 */ 1426 len += hole; 1427 alloc_frag->offset += hole; 1428 } 1429 1430 sg_init_one(rq->sg, buf, len); 1431 ctx = mergeable_len_to_ctx(len, headroom); 1432 err = virtqueue_add_inbuf_ctx(rq->vq, rq->sg, 1, buf, ctx, gfp); 1433 if (err < 0) 1434 put_page(virt_to_head_page(buf)); 1435 1436 return err; 1437 } 1438 1439 /* 1440 * Returns false if we couldn't fill entirely (OOM). 1441 * 1442 * Normally run in the receive path, but can also be run from ndo_open 1443 * before we're receiving packets, or from refill_work which is 1444 * careful to disable receiving (using napi_disable). 1445 */ 1446 static bool try_fill_recv(struct virtnet_info *vi, struct receive_queue *rq, 1447 gfp_t gfp) 1448 { 1449 int err; 1450 bool oom; 1451 1452 do { 1453 if (vi->mergeable_rx_bufs) 1454 err = add_recvbuf_mergeable(vi, rq, gfp); 1455 else if (vi->big_packets) 1456 err = add_recvbuf_big(vi, rq, gfp); 1457 else 1458 err = add_recvbuf_small(vi, rq, gfp); 1459 1460 oom = err == -ENOMEM; 1461 if (err) 1462 break; 1463 } while (rq->vq->num_free); 1464 if (virtqueue_kick_prepare(rq->vq) && virtqueue_notify(rq->vq)) { 1465 unsigned long flags; 1466 1467 flags = u64_stats_update_begin_irqsave(&rq->stats.syncp); 1468 rq->stats.kicks++; 1469 u64_stats_update_end_irqrestore(&rq->stats.syncp, flags); 1470 } 1471 1472 return !oom; 1473 } 1474 1475 static void skb_recv_done(struct virtqueue *rvq) 1476 { 1477 struct virtnet_info *vi = rvq->vdev->priv; 1478 struct receive_queue *rq = &vi->rq[vq2rxq(rvq)]; 1479 1480 virtqueue_napi_schedule(&rq->napi, rvq); 1481 } 1482 1483 static void virtnet_napi_enable(struct virtqueue *vq, struct napi_struct *napi) 1484 { 1485 napi_enable(napi); 1486 1487 /* If all buffers were filled by other side before we napi_enabled, we 1488 * won't get another interrupt, so process any outstanding packets now. 1489 * Call local_bh_enable after to trigger softIRQ processing. 1490 */ 1491 local_bh_disable(); 1492 virtqueue_napi_schedule(napi, vq); 1493 local_bh_enable(); 1494 } 1495 1496 static void virtnet_napi_tx_enable(struct virtnet_info *vi, 1497 struct virtqueue *vq, 1498 struct napi_struct *napi) 1499 { 1500 if (!napi->weight) 1501 return; 1502 1503 /* Tx napi touches cachelines on the cpu handling tx interrupts. Only 1504 * enable the feature if this is likely affine with the transmit path. 1505 */ 1506 if (!vi->affinity_hint_set) { 1507 napi->weight = 0; 1508 return; 1509 } 1510 1511 return virtnet_napi_enable(vq, napi); 1512 } 1513 1514 static void virtnet_napi_tx_disable(struct napi_struct *napi) 1515 { 1516 if (napi->weight) 1517 napi_disable(napi); 1518 } 1519 1520 static void refill_work(struct work_struct *work) 1521 { 1522 struct virtnet_info *vi = 1523 container_of(work, struct virtnet_info, refill.work); 1524 bool still_empty; 1525 int i; 1526 1527 for (i = 0; i < vi->curr_queue_pairs; i++) { 1528 struct receive_queue *rq = &vi->rq[i]; 1529 1530 napi_disable(&rq->napi); 1531 still_empty = !try_fill_recv(vi, rq, GFP_KERNEL); 1532 virtnet_napi_enable(rq->vq, &rq->napi); 1533 1534 /* In theory, this can happen: if we don't get any buffers in 1535 * we will *never* try to fill again. 1536 */ 1537 if (still_empty) 1538 schedule_delayed_work(&vi->refill, HZ/2); 1539 } 1540 } 1541 1542 static int virtnet_receive(struct receive_queue *rq, int budget, 1543 unsigned int *xdp_xmit) 1544 { 1545 struct virtnet_info *vi = rq->vq->vdev->priv; 1546 struct virtnet_rq_stats stats = {}; 1547 unsigned int len; 1548 void *buf; 1549 int i; 1550 1551 if (!vi->big_packets || vi->mergeable_rx_bufs) { 1552 void *ctx; 1553 1554 while (stats.packets < budget && 1555 (buf = virtqueue_get_buf_ctx(rq->vq, &len, &ctx))) { 1556 receive_buf(vi, rq, buf, len, ctx, xdp_xmit, &stats); 1557 stats.packets++; 1558 } 1559 } else { 1560 while (stats.packets < budget && 1561 (buf = virtqueue_get_buf(rq->vq, &len)) != NULL) { 1562 receive_buf(vi, rq, buf, len, NULL, xdp_xmit, &stats); 1563 stats.packets++; 1564 } 1565 } 1566 1567 if (rq->vq->num_free > min((unsigned int)budget, virtqueue_get_vring_size(rq->vq)) / 2) { 1568 if (!try_fill_recv(vi, rq, GFP_ATOMIC)) { 1569 spin_lock(&vi->refill_lock); 1570 if (vi->refill_enabled) 1571 schedule_delayed_work(&vi->refill, 0); 1572 spin_unlock(&vi->refill_lock); 1573 } 1574 } 1575 1576 u64_stats_update_begin(&rq->stats.syncp); 1577 for (i = 0; i < VIRTNET_RQ_STATS_LEN; i++) { 1578 size_t offset = virtnet_rq_stats_desc[i].offset; 1579 u64 *item; 1580 1581 item = (u64 *)((u8 *)&rq->stats + offset); 1582 *item += *(u64 *)((u8 *)&stats + offset); 1583 } 1584 u64_stats_update_end(&rq->stats.syncp); 1585 1586 return stats.packets; 1587 } 1588 1589 static void free_old_xmit_skbs(struct send_queue *sq, bool in_napi) 1590 { 1591 unsigned int len; 1592 unsigned int packets = 0; 1593 unsigned int bytes = 0; 1594 void *ptr; 1595 1596 while ((ptr = virtqueue_get_buf(sq->vq, &len)) != NULL) { 1597 if (likely(!is_xdp_frame(ptr))) { 1598 struct sk_buff *skb = ptr; 1599 1600 pr_debug("Sent skb %p\n", skb); 1601 1602 bytes += skb->len; 1603 napi_consume_skb(skb, in_napi); 1604 } else { 1605 struct xdp_frame *frame = ptr_to_xdp(ptr); 1606 1607 bytes += frame->len; 1608 xdp_return_frame(frame); 1609 } 1610 packets++; 1611 } 1612 1613 /* Avoid overhead when no packets have been processed 1614 * happens when called speculatively from start_xmit. 1615 */ 1616 if (!packets) 1617 return; 1618 1619 u64_stats_update_begin(&sq->stats.syncp); 1620 sq->stats.bytes += bytes; 1621 sq->stats.packets += packets; 1622 u64_stats_update_end(&sq->stats.syncp); 1623 } 1624 1625 static bool is_xdp_raw_buffer_queue(struct virtnet_info *vi, int q) 1626 { 1627 if (q < (vi->curr_queue_pairs - vi->xdp_queue_pairs)) 1628 return false; 1629 else if (q < vi->curr_queue_pairs) 1630 return true; 1631 else 1632 return false; 1633 } 1634 1635 static void virtnet_poll_cleantx(struct receive_queue *rq) 1636 { 1637 struct virtnet_info *vi = rq->vq->vdev->priv; 1638 unsigned int index = vq2rxq(rq->vq); 1639 struct send_queue *sq = &vi->sq[index]; 1640 struct netdev_queue *txq = netdev_get_tx_queue(vi->dev, index); 1641 1642 if (!sq->napi.weight || is_xdp_raw_buffer_queue(vi, index)) 1643 return; 1644 1645 if (__netif_tx_trylock(txq)) { 1646 if (sq->reset) { 1647 __netif_tx_unlock(txq); 1648 return; 1649 } 1650 1651 do { 1652 virtqueue_disable_cb(sq->vq); 1653 free_old_xmit_skbs(sq, true); 1654 } while (unlikely(!virtqueue_enable_cb_delayed(sq->vq))); 1655 1656 if (sq->vq->num_free >= 2 + MAX_SKB_FRAGS) 1657 netif_tx_wake_queue(txq); 1658 1659 __netif_tx_unlock(txq); 1660 } 1661 } 1662 1663 static int virtnet_poll(struct napi_struct *napi, int budget) 1664 { 1665 struct receive_queue *rq = 1666 container_of(napi, struct receive_queue, napi); 1667 struct virtnet_info *vi = rq->vq->vdev->priv; 1668 struct send_queue *sq; 1669 unsigned int received; 1670 unsigned int xdp_xmit = 0; 1671 1672 virtnet_poll_cleantx(rq); 1673 1674 received = virtnet_receive(rq, budget, &xdp_xmit); 1675 1676 /* Out of packets? */ 1677 if (received < budget) 1678 virtqueue_napi_complete(napi, rq->vq, received); 1679 1680 if (xdp_xmit & VIRTIO_XDP_REDIR) 1681 xdp_do_flush(); 1682 1683 if (xdp_xmit & VIRTIO_XDP_TX) { 1684 sq = virtnet_xdp_get_sq(vi); 1685 if (virtqueue_kick_prepare(sq->vq) && virtqueue_notify(sq->vq)) { 1686 u64_stats_update_begin(&sq->stats.syncp); 1687 sq->stats.kicks++; 1688 u64_stats_update_end(&sq->stats.syncp); 1689 } 1690 virtnet_xdp_put_sq(vi, sq); 1691 } 1692 1693 return received; 1694 } 1695 1696 static int virtnet_open(struct net_device *dev) 1697 { 1698 struct virtnet_info *vi = netdev_priv(dev); 1699 int i, err; 1700 1701 enable_delayed_refill(vi); 1702 1703 for (i = 0; i < vi->max_queue_pairs; i++) { 1704 if (i < vi->curr_queue_pairs) 1705 /* Make sure we have some buffers: if oom use wq. */ 1706 if (!try_fill_recv(vi, &vi->rq[i], GFP_KERNEL)) 1707 schedule_delayed_work(&vi->refill, 0); 1708 1709 err = xdp_rxq_info_reg(&vi->rq[i].xdp_rxq, dev, i, vi->rq[i].napi.napi_id); 1710 if (err < 0) 1711 return err; 1712 1713 err = xdp_rxq_info_reg_mem_model(&vi->rq[i].xdp_rxq, 1714 MEM_TYPE_PAGE_SHARED, NULL); 1715 if (err < 0) { 1716 xdp_rxq_info_unreg(&vi->rq[i].xdp_rxq); 1717 return err; 1718 } 1719 1720 virtnet_napi_enable(vi->rq[i].vq, &vi->rq[i].napi); 1721 virtnet_napi_tx_enable(vi, vi->sq[i].vq, &vi->sq[i].napi); 1722 } 1723 1724 return 0; 1725 } 1726 1727 static int virtnet_poll_tx(struct napi_struct *napi, int budget) 1728 { 1729 struct send_queue *sq = container_of(napi, struct send_queue, napi); 1730 struct virtnet_info *vi = sq->vq->vdev->priv; 1731 unsigned int index = vq2txq(sq->vq); 1732 struct netdev_queue *txq; 1733 int opaque; 1734 bool done; 1735 1736 if (unlikely(is_xdp_raw_buffer_queue(vi, index))) { 1737 /* We don't need to enable cb for XDP */ 1738 napi_complete_done(napi, 0); 1739 return 0; 1740 } 1741 1742 txq = netdev_get_tx_queue(vi->dev, index); 1743 __netif_tx_lock(txq, raw_smp_processor_id()); 1744 virtqueue_disable_cb(sq->vq); 1745 free_old_xmit_skbs(sq, true); 1746 1747 if (sq->vq->num_free >= 2 + MAX_SKB_FRAGS) 1748 netif_tx_wake_queue(txq); 1749 1750 opaque = virtqueue_enable_cb_prepare(sq->vq); 1751 1752 done = napi_complete_done(napi, 0); 1753 1754 if (!done) 1755 virtqueue_disable_cb(sq->vq); 1756 1757 __netif_tx_unlock(txq); 1758 1759 if (done) { 1760 if (unlikely(virtqueue_poll(sq->vq, opaque))) { 1761 if (napi_schedule_prep(napi)) { 1762 __netif_tx_lock(txq, raw_smp_processor_id()); 1763 virtqueue_disable_cb(sq->vq); 1764 __netif_tx_unlock(txq); 1765 __napi_schedule(napi); 1766 } 1767 } 1768 } 1769 1770 return 0; 1771 } 1772 1773 static int xmit_skb(struct send_queue *sq, struct sk_buff *skb) 1774 { 1775 struct virtio_net_hdr_mrg_rxbuf *hdr; 1776 const unsigned char *dest = ((struct ethhdr *)skb->data)->h_dest; 1777 struct virtnet_info *vi = sq->vq->vdev->priv; 1778 int num_sg; 1779 unsigned hdr_len = vi->hdr_len; 1780 bool can_push; 1781 1782 pr_debug("%s: xmit %p %pM\n", vi->dev->name, skb, dest); 1783 1784 can_push = vi->any_header_sg && 1785 !((unsigned long)skb->data & (__alignof__(*hdr) - 1)) && 1786 !skb_header_cloned(skb) && skb_headroom(skb) >= hdr_len; 1787 /* Even if we can, don't push here yet as this would skew 1788 * csum_start offset below. */ 1789 if (can_push) 1790 hdr = (struct virtio_net_hdr_mrg_rxbuf *)(skb->data - hdr_len); 1791 else 1792 hdr = skb_vnet_hdr(skb); 1793 1794 if (virtio_net_hdr_from_skb(skb, &hdr->hdr, 1795 virtio_is_little_endian(vi->vdev), false, 1796 0)) 1797 return -EPROTO; 1798 1799 if (vi->mergeable_rx_bufs) 1800 hdr->num_buffers = 0; 1801 1802 sg_init_table(sq->sg, skb_shinfo(skb)->nr_frags + (can_push ? 1 : 2)); 1803 if (can_push) { 1804 __skb_push(skb, hdr_len); 1805 num_sg = skb_to_sgvec(skb, sq->sg, 0, skb->len); 1806 if (unlikely(num_sg < 0)) 1807 return num_sg; 1808 /* Pull header back to avoid skew in tx bytes calculations. */ 1809 __skb_pull(skb, hdr_len); 1810 } else { 1811 sg_set_buf(sq->sg, hdr, hdr_len); 1812 num_sg = skb_to_sgvec(skb, sq->sg + 1, 0, skb->len); 1813 if (unlikely(num_sg < 0)) 1814 return num_sg; 1815 num_sg++; 1816 } 1817 return virtqueue_add_outbuf(sq->vq, sq->sg, num_sg, skb, GFP_ATOMIC); 1818 } 1819 1820 static netdev_tx_t start_xmit(struct sk_buff *skb, struct net_device *dev) 1821 { 1822 struct virtnet_info *vi = netdev_priv(dev); 1823 int qnum = skb_get_queue_mapping(skb); 1824 struct send_queue *sq = &vi->sq[qnum]; 1825 int err; 1826 struct netdev_queue *txq = netdev_get_tx_queue(dev, qnum); 1827 bool kick = !netdev_xmit_more(); 1828 bool use_napi = sq->napi.weight; 1829 1830 /* Free up any pending old buffers before queueing new ones. */ 1831 do { 1832 if (use_napi) 1833 virtqueue_disable_cb(sq->vq); 1834 1835 free_old_xmit_skbs(sq, false); 1836 1837 } while (use_napi && kick && 1838 unlikely(!virtqueue_enable_cb_delayed(sq->vq))); 1839 1840 /* timestamp packet in software */ 1841 skb_tx_timestamp(skb); 1842 1843 /* Try to transmit */ 1844 err = xmit_skb(sq, skb); 1845 1846 /* This should not happen! */ 1847 if (unlikely(err)) { 1848 dev->stats.tx_fifo_errors++; 1849 if (net_ratelimit()) 1850 dev_warn(&dev->dev, 1851 "Unexpected TXQ (%d) queue failure: %d\n", 1852 qnum, err); 1853 dev->stats.tx_dropped++; 1854 dev_kfree_skb_any(skb); 1855 return NETDEV_TX_OK; 1856 } 1857 1858 /* Don't wait up for transmitted skbs to be freed. */ 1859 if (!use_napi) { 1860 skb_orphan(skb); 1861 nf_reset_ct(skb); 1862 } 1863 1864 /* If running out of space, stop queue to avoid getting packets that we 1865 * are then unable to transmit. 1866 * An alternative would be to force queuing layer to requeue the skb by 1867 * returning NETDEV_TX_BUSY. However, NETDEV_TX_BUSY should not be 1868 * returned in a normal path of operation: it means that driver is not 1869 * maintaining the TX queue stop/start state properly, and causes 1870 * the stack to do a non-trivial amount of useless work. 1871 * Since most packets only take 1 or 2 ring slots, stopping the queue 1872 * early means 16 slots are typically wasted. 1873 */ 1874 if (sq->vq->num_free < 2+MAX_SKB_FRAGS) { 1875 netif_stop_subqueue(dev, qnum); 1876 if (!use_napi && 1877 unlikely(!virtqueue_enable_cb_delayed(sq->vq))) { 1878 /* More just got used, free them then recheck. */ 1879 free_old_xmit_skbs(sq, false); 1880 if (sq->vq->num_free >= 2+MAX_SKB_FRAGS) { 1881 netif_start_subqueue(dev, qnum); 1882 virtqueue_disable_cb(sq->vq); 1883 } 1884 } 1885 } 1886 1887 if (kick || netif_xmit_stopped(txq)) { 1888 if (virtqueue_kick_prepare(sq->vq) && virtqueue_notify(sq->vq)) { 1889 u64_stats_update_begin(&sq->stats.syncp); 1890 sq->stats.kicks++; 1891 u64_stats_update_end(&sq->stats.syncp); 1892 } 1893 } 1894 1895 return NETDEV_TX_OK; 1896 } 1897 1898 static int virtnet_rx_resize(struct virtnet_info *vi, 1899 struct receive_queue *rq, u32 ring_num) 1900 { 1901 bool running = netif_running(vi->dev); 1902 int err, qindex; 1903 1904 qindex = rq - vi->rq; 1905 1906 if (running) 1907 napi_disable(&rq->napi); 1908 1909 err = virtqueue_resize(rq->vq, ring_num, virtnet_rq_free_unused_buf); 1910 if (err) 1911 netdev_err(vi->dev, "resize rx fail: rx queue index: %d err: %d\n", qindex, err); 1912 1913 if (!try_fill_recv(vi, rq, GFP_KERNEL)) 1914 schedule_delayed_work(&vi->refill, 0); 1915 1916 if (running) 1917 virtnet_napi_enable(rq->vq, &rq->napi); 1918 return err; 1919 } 1920 1921 static int virtnet_tx_resize(struct virtnet_info *vi, 1922 struct send_queue *sq, u32 ring_num) 1923 { 1924 bool running = netif_running(vi->dev); 1925 struct netdev_queue *txq; 1926 int err, qindex; 1927 1928 qindex = sq - vi->sq; 1929 1930 if (running) 1931 virtnet_napi_tx_disable(&sq->napi); 1932 1933 txq = netdev_get_tx_queue(vi->dev, qindex); 1934 1935 /* 1. wait all ximt complete 1936 * 2. fix the race of netif_stop_subqueue() vs netif_start_subqueue() 1937 */ 1938 __netif_tx_lock_bh(txq); 1939 1940 /* Prevent rx poll from accessing sq. */ 1941 sq->reset = true; 1942 1943 /* Prevent the upper layer from trying to send packets. */ 1944 netif_stop_subqueue(vi->dev, qindex); 1945 1946 __netif_tx_unlock_bh(txq); 1947 1948 err = virtqueue_resize(sq->vq, ring_num, virtnet_sq_free_unused_buf); 1949 if (err) 1950 netdev_err(vi->dev, "resize tx fail: tx queue index: %d err: %d\n", qindex, err); 1951 1952 __netif_tx_lock_bh(txq); 1953 sq->reset = false; 1954 netif_tx_wake_queue(txq); 1955 __netif_tx_unlock_bh(txq); 1956 1957 if (running) 1958 virtnet_napi_tx_enable(vi, sq->vq, &sq->napi); 1959 return err; 1960 } 1961 1962 /* 1963 * Send command via the control virtqueue and check status. Commands 1964 * supported by the hypervisor, as indicated by feature bits, should 1965 * never fail unless improperly formatted. 1966 */ 1967 static bool virtnet_send_command(struct virtnet_info *vi, u8 class, u8 cmd, 1968 struct scatterlist *out) 1969 { 1970 struct scatterlist *sgs[4], hdr, stat; 1971 unsigned out_num = 0, tmp; 1972 int ret; 1973 1974 /* Caller should know better */ 1975 BUG_ON(!virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ)); 1976 1977 vi->ctrl->status = ~0; 1978 vi->ctrl->hdr.class = class; 1979 vi->ctrl->hdr.cmd = cmd; 1980 /* Add header */ 1981 sg_init_one(&hdr, &vi->ctrl->hdr, sizeof(vi->ctrl->hdr)); 1982 sgs[out_num++] = &hdr; 1983 1984 if (out) 1985 sgs[out_num++] = out; 1986 1987 /* Add return status. */ 1988 sg_init_one(&stat, &vi->ctrl->status, sizeof(vi->ctrl->status)); 1989 sgs[out_num] = &stat; 1990 1991 BUG_ON(out_num + 1 > ARRAY_SIZE(sgs)); 1992 ret = virtqueue_add_sgs(vi->cvq, sgs, out_num, 1, vi, GFP_ATOMIC); 1993 if (ret < 0) { 1994 dev_warn(&vi->vdev->dev, 1995 "Failed to add sgs for command vq: %d\n.", ret); 1996 return false; 1997 } 1998 1999 if (unlikely(!virtqueue_kick(vi->cvq))) 2000 return vi->ctrl->status == VIRTIO_NET_OK; 2001 2002 /* Spin for a response, the kick causes an ioport write, trapping 2003 * into the hypervisor, so the request should be handled immediately. 2004 */ 2005 while (!virtqueue_get_buf(vi->cvq, &tmp) && 2006 !virtqueue_is_broken(vi->cvq)) 2007 cpu_relax(); 2008 2009 return vi->ctrl->status == VIRTIO_NET_OK; 2010 } 2011 2012 static int virtnet_set_mac_address(struct net_device *dev, void *p) 2013 { 2014 struct virtnet_info *vi = netdev_priv(dev); 2015 struct virtio_device *vdev = vi->vdev; 2016 int ret; 2017 struct sockaddr *addr; 2018 struct scatterlist sg; 2019 2020 if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_STANDBY)) 2021 return -EOPNOTSUPP; 2022 2023 addr = kmemdup(p, sizeof(*addr), GFP_KERNEL); 2024 if (!addr) 2025 return -ENOMEM; 2026 2027 ret = eth_prepare_mac_addr_change(dev, addr); 2028 if (ret) 2029 goto out; 2030 2031 if (virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_MAC_ADDR)) { 2032 sg_init_one(&sg, addr->sa_data, dev->addr_len); 2033 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_MAC, 2034 VIRTIO_NET_CTRL_MAC_ADDR_SET, &sg)) { 2035 dev_warn(&vdev->dev, 2036 "Failed to set mac address by vq command.\n"); 2037 ret = -EINVAL; 2038 goto out; 2039 } 2040 } else if (virtio_has_feature(vdev, VIRTIO_NET_F_MAC) && 2041 !virtio_has_feature(vdev, VIRTIO_F_VERSION_1)) { 2042 unsigned int i; 2043 2044 /* Naturally, this has an atomicity problem. */ 2045 for (i = 0; i < dev->addr_len; i++) 2046 virtio_cwrite8(vdev, 2047 offsetof(struct virtio_net_config, mac) + 2048 i, addr->sa_data[i]); 2049 } 2050 2051 eth_commit_mac_addr_change(dev, p); 2052 ret = 0; 2053 2054 out: 2055 kfree(addr); 2056 return ret; 2057 } 2058 2059 static void virtnet_stats(struct net_device *dev, 2060 struct rtnl_link_stats64 *tot) 2061 { 2062 struct virtnet_info *vi = netdev_priv(dev); 2063 unsigned int start; 2064 int i; 2065 2066 for (i = 0; i < vi->max_queue_pairs; i++) { 2067 u64 tpackets, tbytes, terrors, rpackets, rbytes, rdrops; 2068 struct receive_queue *rq = &vi->rq[i]; 2069 struct send_queue *sq = &vi->sq[i]; 2070 2071 do { 2072 start = u64_stats_fetch_begin_irq(&sq->stats.syncp); 2073 tpackets = sq->stats.packets; 2074 tbytes = sq->stats.bytes; 2075 terrors = sq->stats.tx_timeouts; 2076 } while (u64_stats_fetch_retry_irq(&sq->stats.syncp, start)); 2077 2078 do { 2079 start = u64_stats_fetch_begin_irq(&rq->stats.syncp); 2080 rpackets = rq->stats.packets; 2081 rbytes = rq->stats.bytes; 2082 rdrops = rq->stats.drops; 2083 } while (u64_stats_fetch_retry_irq(&rq->stats.syncp, start)); 2084 2085 tot->rx_packets += rpackets; 2086 tot->tx_packets += tpackets; 2087 tot->rx_bytes += rbytes; 2088 tot->tx_bytes += tbytes; 2089 tot->rx_dropped += rdrops; 2090 tot->tx_errors += terrors; 2091 } 2092 2093 tot->tx_dropped = dev->stats.tx_dropped; 2094 tot->tx_fifo_errors = dev->stats.tx_fifo_errors; 2095 tot->rx_length_errors = dev->stats.rx_length_errors; 2096 tot->rx_frame_errors = dev->stats.rx_frame_errors; 2097 } 2098 2099 static void virtnet_ack_link_announce(struct virtnet_info *vi) 2100 { 2101 rtnl_lock(); 2102 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_ANNOUNCE, 2103 VIRTIO_NET_CTRL_ANNOUNCE_ACK, NULL)) 2104 dev_warn(&vi->dev->dev, "Failed to ack link announce.\n"); 2105 rtnl_unlock(); 2106 } 2107 2108 static int _virtnet_set_queues(struct virtnet_info *vi, u16 queue_pairs) 2109 { 2110 struct scatterlist sg; 2111 struct net_device *dev = vi->dev; 2112 2113 if (!vi->has_cvq || !virtio_has_feature(vi->vdev, VIRTIO_NET_F_MQ)) 2114 return 0; 2115 2116 vi->ctrl->mq.virtqueue_pairs = cpu_to_virtio16(vi->vdev, queue_pairs); 2117 sg_init_one(&sg, &vi->ctrl->mq, sizeof(vi->ctrl->mq)); 2118 2119 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_MQ, 2120 VIRTIO_NET_CTRL_MQ_VQ_PAIRS_SET, &sg)) { 2121 dev_warn(&dev->dev, "Fail to set num of queue pairs to %d\n", 2122 queue_pairs); 2123 return -EINVAL; 2124 } else { 2125 vi->curr_queue_pairs = queue_pairs; 2126 /* virtnet_open() will refill when device is going to up. */ 2127 if (dev->flags & IFF_UP) 2128 schedule_delayed_work(&vi->refill, 0); 2129 } 2130 2131 return 0; 2132 } 2133 2134 static int virtnet_set_queues(struct virtnet_info *vi, u16 queue_pairs) 2135 { 2136 int err; 2137 2138 rtnl_lock(); 2139 err = _virtnet_set_queues(vi, queue_pairs); 2140 rtnl_unlock(); 2141 return err; 2142 } 2143 2144 static int virtnet_close(struct net_device *dev) 2145 { 2146 struct virtnet_info *vi = netdev_priv(dev); 2147 int i; 2148 2149 /* Make sure NAPI doesn't schedule refill work */ 2150 disable_delayed_refill(vi); 2151 /* Make sure refill_work doesn't re-enable napi! */ 2152 cancel_delayed_work_sync(&vi->refill); 2153 2154 for (i = 0; i < vi->max_queue_pairs; i++) { 2155 xdp_rxq_info_unreg(&vi->rq[i].xdp_rxq); 2156 napi_disable(&vi->rq[i].napi); 2157 virtnet_napi_tx_disable(&vi->sq[i].napi); 2158 } 2159 2160 return 0; 2161 } 2162 2163 static void virtnet_set_rx_mode(struct net_device *dev) 2164 { 2165 struct virtnet_info *vi = netdev_priv(dev); 2166 struct scatterlist sg[2]; 2167 struct virtio_net_ctrl_mac *mac_data; 2168 struct netdev_hw_addr *ha; 2169 int uc_count; 2170 int mc_count; 2171 void *buf; 2172 int i; 2173 2174 /* We can't dynamically set ndo_set_rx_mode, so return gracefully */ 2175 if (!virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_RX)) 2176 return; 2177 2178 vi->ctrl->promisc = ((dev->flags & IFF_PROMISC) != 0); 2179 vi->ctrl->allmulti = ((dev->flags & IFF_ALLMULTI) != 0); 2180 2181 sg_init_one(sg, &vi->ctrl->promisc, sizeof(vi->ctrl->promisc)); 2182 2183 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_RX, 2184 VIRTIO_NET_CTRL_RX_PROMISC, sg)) 2185 dev_warn(&dev->dev, "Failed to %sable promisc mode.\n", 2186 vi->ctrl->promisc ? "en" : "dis"); 2187 2188 sg_init_one(sg, &vi->ctrl->allmulti, sizeof(vi->ctrl->allmulti)); 2189 2190 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_RX, 2191 VIRTIO_NET_CTRL_RX_ALLMULTI, sg)) 2192 dev_warn(&dev->dev, "Failed to %sable allmulti mode.\n", 2193 vi->ctrl->allmulti ? "en" : "dis"); 2194 2195 uc_count = netdev_uc_count(dev); 2196 mc_count = netdev_mc_count(dev); 2197 /* MAC filter - use one buffer for both lists */ 2198 buf = kzalloc(((uc_count + mc_count) * ETH_ALEN) + 2199 (2 * sizeof(mac_data->entries)), GFP_ATOMIC); 2200 mac_data = buf; 2201 if (!buf) 2202 return; 2203 2204 sg_init_table(sg, 2); 2205 2206 /* Store the unicast list and count in the front of the buffer */ 2207 mac_data->entries = cpu_to_virtio32(vi->vdev, uc_count); 2208 i = 0; 2209 netdev_for_each_uc_addr(ha, dev) 2210 memcpy(&mac_data->macs[i++][0], ha->addr, ETH_ALEN); 2211 2212 sg_set_buf(&sg[0], mac_data, 2213 sizeof(mac_data->entries) + (uc_count * ETH_ALEN)); 2214 2215 /* multicast list and count fill the end */ 2216 mac_data = (void *)&mac_data->macs[uc_count][0]; 2217 2218 mac_data->entries = cpu_to_virtio32(vi->vdev, mc_count); 2219 i = 0; 2220 netdev_for_each_mc_addr(ha, dev) 2221 memcpy(&mac_data->macs[i++][0], ha->addr, ETH_ALEN); 2222 2223 sg_set_buf(&sg[1], mac_data, 2224 sizeof(mac_data->entries) + (mc_count * ETH_ALEN)); 2225 2226 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_MAC, 2227 VIRTIO_NET_CTRL_MAC_TABLE_SET, sg)) 2228 dev_warn(&dev->dev, "Failed to set MAC filter table.\n"); 2229 2230 kfree(buf); 2231 } 2232 2233 static int virtnet_vlan_rx_add_vid(struct net_device *dev, 2234 __be16 proto, u16 vid) 2235 { 2236 struct virtnet_info *vi = netdev_priv(dev); 2237 struct scatterlist sg; 2238 2239 vi->ctrl->vid = cpu_to_virtio16(vi->vdev, vid); 2240 sg_init_one(&sg, &vi->ctrl->vid, sizeof(vi->ctrl->vid)); 2241 2242 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_VLAN, 2243 VIRTIO_NET_CTRL_VLAN_ADD, &sg)) 2244 dev_warn(&dev->dev, "Failed to add VLAN ID %d.\n", vid); 2245 return 0; 2246 } 2247 2248 static int virtnet_vlan_rx_kill_vid(struct net_device *dev, 2249 __be16 proto, u16 vid) 2250 { 2251 struct virtnet_info *vi = netdev_priv(dev); 2252 struct scatterlist sg; 2253 2254 vi->ctrl->vid = cpu_to_virtio16(vi->vdev, vid); 2255 sg_init_one(&sg, &vi->ctrl->vid, sizeof(vi->ctrl->vid)); 2256 2257 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_VLAN, 2258 VIRTIO_NET_CTRL_VLAN_DEL, &sg)) 2259 dev_warn(&dev->dev, "Failed to kill VLAN ID %d.\n", vid); 2260 return 0; 2261 } 2262 2263 static void virtnet_clean_affinity(struct virtnet_info *vi) 2264 { 2265 int i; 2266 2267 if (vi->affinity_hint_set) { 2268 for (i = 0; i < vi->max_queue_pairs; i++) { 2269 virtqueue_set_affinity(vi->rq[i].vq, NULL); 2270 virtqueue_set_affinity(vi->sq[i].vq, NULL); 2271 } 2272 2273 vi->affinity_hint_set = false; 2274 } 2275 } 2276 2277 static void virtnet_set_affinity(struct virtnet_info *vi) 2278 { 2279 cpumask_var_t mask; 2280 int stragglers; 2281 int group_size; 2282 int i, j, cpu; 2283 int num_cpu; 2284 int stride; 2285 2286 if (!zalloc_cpumask_var(&mask, GFP_KERNEL)) { 2287 virtnet_clean_affinity(vi); 2288 return; 2289 } 2290 2291 num_cpu = num_online_cpus(); 2292 stride = max_t(int, num_cpu / vi->curr_queue_pairs, 1); 2293 stragglers = num_cpu >= vi->curr_queue_pairs ? 2294 num_cpu % vi->curr_queue_pairs : 2295 0; 2296 cpu = cpumask_first(cpu_online_mask); 2297 2298 for (i = 0; i < vi->curr_queue_pairs; i++) { 2299 group_size = stride + (i < stragglers ? 1 : 0); 2300 2301 for (j = 0; j < group_size; j++) { 2302 cpumask_set_cpu(cpu, mask); 2303 cpu = cpumask_next_wrap(cpu, cpu_online_mask, 2304 nr_cpu_ids, false); 2305 } 2306 virtqueue_set_affinity(vi->rq[i].vq, mask); 2307 virtqueue_set_affinity(vi->sq[i].vq, mask); 2308 __netif_set_xps_queue(vi->dev, cpumask_bits(mask), i, XPS_CPUS); 2309 cpumask_clear(mask); 2310 } 2311 2312 vi->affinity_hint_set = true; 2313 free_cpumask_var(mask); 2314 } 2315 2316 static int virtnet_cpu_online(unsigned int cpu, struct hlist_node *node) 2317 { 2318 struct virtnet_info *vi = hlist_entry_safe(node, struct virtnet_info, 2319 node); 2320 virtnet_set_affinity(vi); 2321 return 0; 2322 } 2323 2324 static int virtnet_cpu_dead(unsigned int cpu, struct hlist_node *node) 2325 { 2326 struct virtnet_info *vi = hlist_entry_safe(node, struct virtnet_info, 2327 node_dead); 2328 virtnet_set_affinity(vi); 2329 return 0; 2330 } 2331 2332 static int virtnet_cpu_down_prep(unsigned int cpu, struct hlist_node *node) 2333 { 2334 struct virtnet_info *vi = hlist_entry_safe(node, struct virtnet_info, 2335 node); 2336 2337 virtnet_clean_affinity(vi); 2338 return 0; 2339 } 2340 2341 static enum cpuhp_state virtionet_online; 2342 2343 static int virtnet_cpu_notif_add(struct virtnet_info *vi) 2344 { 2345 int ret; 2346 2347 ret = cpuhp_state_add_instance_nocalls(virtionet_online, &vi->node); 2348 if (ret) 2349 return ret; 2350 ret = cpuhp_state_add_instance_nocalls(CPUHP_VIRT_NET_DEAD, 2351 &vi->node_dead); 2352 if (!ret) 2353 return ret; 2354 cpuhp_state_remove_instance_nocalls(virtionet_online, &vi->node); 2355 return ret; 2356 } 2357 2358 static void virtnet_cpu_notif_remove(struct virtnet_info *vi) 2359 { 2360 cpuhp_state_remove_instance_nocalls(virtionet_online, &vi->node); 2361 cpuhp_state_remove_instance_nocalls(CPUHP_VIRT_NET_DEAD, 2362 &vi->node_dead); 2363 } 2364 2365 static void virtnet_get_ringparam(struct net_device *dev, 2366 struct ethtool_ringparam *ring, 2367 struct kernel_ethtool_ringparam *kernel_ring, 2368 struct netlink_ext_ack *extack) 2369 { 2370 struct virtnet_info *vi = netdev_priv(dev); 2371 2372 ring->rx_max_pending = vi->rq[0].vq->num_max; 2373 ring->tx_max_pending = vi->sq[0].vq->num_max; 2374 ring->rx_pending = virtqueue_get_vring_size(vi->rq[0].vq); 2375 ring->tx_pending = virtqueue_get_vring_size(vi->sq[0].vq); 2376 } 2377 2378 static int virtnet_set_ringparam(struct net_device *dev, 2379 struct ethtool_ringparam *ring, 2380 struct kernel_ethtool_ringparam *kernel_ring, 2381 struct netlink_ext_ack *extack) 2382 { 2383 struct virtnet_info *vi = netdev_priv(dev); 2384 u32 rx_pending, tx_pending; 2385 struct receive_queue *rq; 2386 struct send_queue *sq; 2387 int i, err; 2388 2389 if (ring->rx_mini_pending || ring->rx_jumbo_pending) 2390 return -EINVAL; 2391 2392 rx_pending = virtqueue_get_vring_size(vi->rq[0].vq); 2393 tx_pending = virtqueue_get_vring_size(vi->sq[0].vq); 2394 2395 if (ring->rx_pending == rx_pending && 2396 ring->tx_pending == tx_pending) 2397 return 0; 2398 2399 if (ring->rx_pending > vi->rq[0].vq->num_max) 2400 return -EINVAL; 2401 2402 if (ring->tx_pending > vi->sq[0].vq->num_max) 2403 return -EINVAL; 2404 2405 for (i = 0; i < vi->max_queue_pairs; i++) { 2406 rq = vi->rq + i; 2407 sq = vi->sq + i; 2408 2409 if (ring->tx_pending != tx_pending) { 2410 err = virtnet_tx_resize(vi, sq, ring->tx_pending); 2411 if (err) 2412 return err; 2413 } 2414 2415 if (ring->rx_pending != rx_pending) { 2416 err = virtnet_rx_resize(vi, rq, ring->rx_pending); 2417 if (err) 2418 return err; 2419 } 2420 } 2421 2422 return 0; 2423 } 2424 2425 static bool virtnet_commit_rss_command(struct virtnet_info *vi) 2426 { 2427 struct net_device *dev = vi->dev; 2428 struct scatterlist sgs[4]; 2429 unsigned int sg_buf_size; 2430 2431 /* prepare sgs */ 2432 sg_init_table(sgs, 4); 2433 2434 sg_buf_size = offsetof(struct virtio_net_ctrl_rss, indirection_table); 2435 sg_set_buf(&sgs[0], &vi->ctrl->rss, sg_buf_size); 2436 2437 sg_buf_size = sizeof(uint16_t) * (vi->ctrl->rss.indirection_table_mask + 1); 2438 sg_set_buf(&sgs[1], vi->ctrl->rss.indirection_table, sg_buf_size); 2439 2440 sg_buf_size = offsetof(struct virtio_net_ctrl_rss, key) 2441 - offsetof(struct virtio_net_ctrl_rss, max_tx_vq); 2442 sg_set_buf(&sgs[2], &vi->ctrl->rss.max_tx_vq, sg_buf_size); 2443 2444 sg_buf_size = vi->rss_key_size; 2445 sg_set_buf(&sgs[3], vi->ctrl->rss.key, sg_buf_size); 2446 2447 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_MQ, 2448 vi->has_rss ? VIRTIO_NET_CTRL_MQ_RSS_CONFIG 2449 : VIRTIO_NET_CTRL_MQ_HASH_CONFIG, sgs)) { 2450 dev_warn(&dev->dev, "VIRTIONET issue with committing RSS sgs\n"); 2451 return false; 2452 } 2453 return true; 2454 } 2455 2456 static void virtnet_init_default_rss(struct virtnet_info *vi) 2457 { 2458 u32 indir_val = 0; 2459 int i = 0; 2460 2461 vi->ctrl->rss.hash_types = vi->rss_hash_types_supported; 2462 vi->rss_hash_types_saved = vi->rss_hash_types_supported; 2463 vi->ctrl->rss.indirection_table_mask = vi->rss_indir_table_size 2464 ? vi->rss_indir_table_size - 1 : 0; 2465 vi->ctrl->rss.unclassified_queue = 0; 2466 2467 for (; i < vi->rss_indir_table_size; ++i) { 2468 indir_val = ethtool_rxfh_indir_default(i, vi->curr_queue_pairs); 2469 vi->ctrl->rss.indirection_table[i] = indir_val; 2470 } 2471 2472 vi->ctrl->rss.max_tx_vq = vi->curr_queue_pairs; 2473 vi->ctrl->rss.hash_key_length = vi->rss_key_size; 2474 2475 netdev_rss_key_fill(vi->ctrl->rss.key, vi->rss_key_size); 2476 } 2477 2478 static void virtnet_get_hashflow(const struct virtnet_info *vi, struct ethtool_rxnfc *info) 2479 { 2480 info->data = 0; 2481 switch (info->flow_type) { 2482 case TCP_V4_FLOW: 2483 if (vi->rss_hash_types_saved & VIRTIO_NET_RSS_HASH_TYPE_TCPv4) { 2484 info->data = RXH_IP_SRC | RXH_IP_DST | 2485 RXH_L4_B_0_1 | RXH_L4_B_2_3; 2486 } else if (vi->rss_hash_types_saved & VIRTIO_NET_RSS_HASH_TYPE_IPv4) { 2487 info->data = RXH_IP_SRC | RXH_IP_DST; 2488 } 2489 break; 2490 case TCP_V6_FLOW: 2491 if (vi->rss_hash_types_saved & VIRTIO_NET_RSS_HASH_TYPE_TCPv6) { 2492 info->data = RXH_IP_SRC | RXH_IP_DST | 2493 RXH_L4_B_0_1 | RXH_L4_B_2_3; 2494 } else if (vi->rss_hash_types_saved & VIRTIO_NET_RSS_HASH_TYPE_IPv6) { 2495 info->data = RXH_IP_SRC | RXH_IP_DST; 2496 } 2497 break; 2498 case UDP_V4_FLOW: 2499 if (vi->rss_hash_types_saved & VIRTIO_NET_RSS_HASH_TYPE_UDPv4) { 2500 info->data = RXH_IP_SRC | RXH_IP_DST | 2501 RXH_L4_B_0_1 | RXH_L4_B_2_3; 2502 } else if (vi->rss_hash_types_saved & VIRTIO_NET_RSS_HASH_TYPE_IPv4) { 2503 info->data = RXH_IP_SRC | RXH_IP_DST; 2504 } 2505 break; 2506 case UDP_V6_FLOW: 2507 if (vi->rss_hash_types_saved & VIRTIO_NET_RSS_HASH_TYPE_UDPv6) { 2508 info->data = RXH_IP_SRC | RXH_IP_DST | 2509 RXH_L4_B_0_1 | RXH_L4_B_2_3; 2510 } else if (vi->rss_hash_types_saved & VIRTIO_NET_RSS_HASH_TYPE_IPv6) { 2511 info->data = RXH_IP_SRC | RXH_IP_DST; 2512 } 2513 break; 2514 case IPV4_FLOW: 2515 if (vi->rss_hash_types_saved & VIRTIO_NET_RSS_HASH_TYPE_IPv4) 2516 info->data = RXH_IP_SRC | RXH_IP_DST; 2517 2518 break; 2519 case IPV6_FLOW: 2520 if (vi->rss_hash_types_saved & VIRTIO_NET_RSS_HASH_TYPE_IPv6) 2521 info->data = RXH_IP_SRC | RXH_IP_DST; 2522 2523 break; 2524 default: 2525 info->data = 0; 2526 break; 2527 } 2528 } 2529 2530 static bool virtnet_set_hashflow(struct virtnet_info *vi, struct ethtool_rxnfc *info) 2531 { 2532 u32 new_hashtypes = vi->rss_hash_types_saved; 2533 bool is_disable = info->data & RXH_DISCARD; 2534 bool is_l4 = info->data == (RXH_IP_SRC | RXH_IP_DST | RXH_L4_B_0_1 | RXH_L4_B_2_3); 2535 2536 /* supports only 'sd', 'sdfn' and 'r' */ 2537 if (!((info->data == (RXH_IP_SRC | RXH_IP_DST)) | is_l4 | is_disable)) 2538 return false; 2539 2540 switch (info->flow_type) { 2541 case TCP_V4_FLOW: 2542 new_hashtypes &= ~(VIRTIO_NET_RSS_HASH_TYPE_IPv4 | VIRTIO_NET_RSS_HASH_TYPE_TCPv4); 2543 if (!is_disable) 2544 new_hashtypes |= VIRTIO_NET_RSS_HASH_TYPE_IPv4 2545 | (is_l4 ? VIRTIO_NET_RSS_HASH_TYPE_TCPv4 : 0); 2546 break; 2547 case UDP_V4_FLOW: 2548 new_hashtypes &= ~(VIRTIO_NET_RSS_HASH_TYPE_IPv4 | VIRTIO_NET_RSS_HASH_TYPE_UDPv4); 2549 if (!is_disable) 2550 new_hashtypes |= VIRTIO_NET_RSS_HASH_TYPE_IPv4 2551 | (is_l4 ? VIRTIO_NET_RSS_HASH_TYPE_UDPv4 : 0); 2552 break; 2553 case IPV4_FLOW: 2554 new_hashtypes &= ~VIRTIO_NET_RSS_HASH_TYPE_IPv4; 2555 if (!is_disable) 2556 new_hashtypes = VIRTIO_NET_RSS_HASH_TYPE_IPv4; 2557 break; 2558 case TCP_V6_FLOW: 2559 new_hashtypes &= ~(VIRTIO_NET_RSS_HASH_TYPE_IPv6 | VIRTIO_NET_RSS_HASH_TYPE_TCPv6); 2560 if (!is_disable) 2561 new_hashtypes |= VIRTIO_NET_RSS_HASH_TYPE_IPv6 2562 | (is_l4 ? VIRTIO_NET_RSS_HASH_TYPE_TCPv6 : 0); 2563 break; 2564 case UDP_V6_FLOW: 2565 new_hashtypes &= ~(VIRTIO_NET_RSS_HASH_TYPE_IPv6 | VIRTIO_NET_RSS_HASH_TYPE_UDPv6); 2566 if (!is_disable) 2567 new_hashtypes |= VIRTIO_NET_RSS_HASH_TYPE_IPv6 2568 | (is_l4 ? VIRTIO_NET_RSS_HASH_TYPE_UDPv6 : 0); 2569 break; 2570 case IPV6_FLOW: 2571 new_hashtypes &= ~VIRTIO_NET_RSS_HASH_TYPE_IPv6; 2572 if (!is_disable) 2573 new_hashtypes = VIRTIO_NET_RSS_HASH_TYPE_IPv6; 2574 break; 2575 default: 2576 /* unsupported flow */ 2577 return false; 2578 } 2579 2580 /* if unsupported hashtype was set */ 2581 if (new_hashtypes != (new_hashtypes & vi->rss_hash_types_supported)) 2582 return false; 2583 2584 if (new_hashtypes != vi->rss_hash_types_saved) { 2585 vi->rss_hash_types_saved = new_hashtypes; 2586 vi->ctrl->rss.hash_types = vi->rss_hash_types_saved; 2587 if (vi->dev->features & NETIF_F_RXHASH) 2588 return virtnet_commit_rss_command(vi); 2589 } 2590 2591 return true; 2592 } 2593 2594 static void virtnet_get_drvinfo(struct net_device *dev, 2595 struct ethtool_drvinfo *info) 2596 { 2597 struct virtnet_info *vi = netdev_priv(dev); 2598 struct virtio_device *vdev = vi->vdev; 2599 2600 strscpy(info->driver, KBUILD_MODNAME, sizeof(info->driver)); 2601 strscpy(info->version, VIRTNET_DRIVER_VERSION, sizeof(info->version)); 2602 strscpy(info->bus_info, virtio_bus_name(vdev), sizeof(info->bus_info)); 2603 2604 } 2605 2606 /* TODO: Eliminate OOO packets during switching */ 2607 static int virtnet_set_channels(struct net_device *dev, 2608 struct ethtool_channels *channels) 2609 { 2610 struct virtnet_info *vi = netdev_priv(dev); 2611 u16 queue_pairs = channels->combined_count; 2612 int err; 2613 2614 /* We don't support separate rx/tx channels. 2615 * We don't allow setting 'other' channels. 2616 */ 2617 if (channels->rx_count || channels->tx_count || channels->other_count) 2618 return -EINVAL; 2619 2620 if (queue_pairs > vi->max_queue_pairs || queue_pairs == 0) 2621 return -EINVAL; 2622 2623 /* For now we don't support modifying channels while XDP is loaded 2624 * also when XDP is loaded all RX queues have XDP programs so we only 2625 * need to check a single RX queue. 2626 */ 2627 if (vi->rq[0].xdp_prog) 2628 return -EINVAL; 2629 2630 cpus_read_lock(); 2631 err = _virtnet_set_queues(vi, queue_pairs); 2632 if (err) { 2633 cpus_read_unlock(); 2634 goto err; 2635 } 2636 virtnet_set_affinity(vi); 2637 cpus_read_unlock(); 2638 2639 netif_set_real_num_tx_queues(dev, queue_pairs); 2640 netif_set_real_num_rx_queues(dev, queue_pairs); 2641 err: 2642 return err; 2643 } 2644 2645 static void virtnet_get_strings(struct net_device *dev, u32 stringset, u8 *data) 2646 { 2647 struct virtnet_info *vi = netdev_priv(dev); 2648 unsigned int i, j; 2649 u8 *p = data; 2650 2651 switch (stringset) { 2652 case ETH_SS_STATS: 2653 for (i = 0; i < vi->curr_queue_pairs; i++) { 2654 for (j = 0; j < VIRTNET_RQ_STATS_LEN; j++) 2655 ethtool_sprintf(&p, "rx_queue_%u_%s", i, 2656 virtnet_rq_stats_desc[j].desc); 2657 } 2658 2659 for (i = 0; i < vi->curr_queue_pairs; i++) { 2660 for (j = 0; j < VIRTNET_SQ_STATS_LEN; j++) 2661 ethtool_sprintf(&p, "tx_queue_%u_%s", i, 2662 virtnet_sq_stats_desc[j].desc); 2663 } 2664 break; 2665 } 2666 } 2667 2668 static int virtnet_get_sset_count(struct net_device *dev, int sset) 2669 { 2670 struct virtnet_info *vi = netdev_priv(dev); 2671 2672 switch (sset) { 2673 case ETH_SS_STATS: 2674 return vi->curr_queue_pairs * (VIRTNET_RQ_STATS_LEN + 2675 VIRTNET_SQ_STATS_LEN); 2676 default: 2677 return -EOPNOTSUPP; 2678 } 2679 } 2680 2681 static void virtnet_get_ethtool_stats(struct net_device *dev, 2682 struct ethtool_stats *stats, u64 *data) 2683 { 2684 struct virtnet_info *vi = netdev_priv(dev); 2685 unsigned int idx = 0, start, i, j; 2686 const u8 *stats_base; 2687 size_t offset; 2688 2689 for (i = 0; i < vi->curr_queue_pairs; i++) { 2690 struct receive_queue *rq = &vi->rq[i]; 2691 2692 stats_base = (u8 *)&rq->stats; 2693 do { 2694 start = u64_stats_fetch_begin_irq(&rq->stats.syncp); 2695 for (j = 0; j < VIRTNET_RQ_STATS_LEN; j++) { 2696 offset = virtnet_rq_stats_desc[j].offset; 2697 data[idx + j] = *(u64 *)(stats_base + offset); 2698 } 2699 } while (u64_stats_fetch_retry_irq(&rq->stats.syncp, start)); 2700 idx += VIRTNET_RQ_STATS_LEN; 2701 } 2702 2703 for (i = 0; i < vi->curr_queue_pairs; i++) { 2704 struct send_queue *sq = &vi->sq[i]; 2705 2706 stats_base = (u8 *)&sq->stats; 2707 do { 2708 start = u64_stats_fetch_begin_irq(&sq->stats.syncp); 2709 for (j = 0; j < VIRTNET_SQ_STATS_LEN; j++) { 2710 offset = virtnet_sq_stats_desc[j].offset; 2711 data[idx + j] = *(u64 *)(stats_base + offset); 2712 } 2713 } while (u64_stats_fetch_retry_irq(&sq->stats.syncp, start)); 2714 idx += VIRTNET_SQ_STATS_LEN; 2715 } 2716 } 2717 2718 static void virtnet_get_channels(struct net_device *dev, 2719 struct ethtool_channels *channels) 2720 { 2721 struct virtnet_info *vi = netdev_priv(dev); 2722 2723 channels->combined_count = vi->curr_queue_pairs; 2724 channels->max_combined = vi->max_queue_pairs; 2725 channels->max_other = 0; 2726 channels->rx_count = 0; 2727 channels->tx_count = 0; 2728 channels->other_count = 0; 2729 } 2730 2731 static int virtnet_set_link_ksettings(struct net_device *dev, 2732 const struct ethtool_link_ksettings *cmd) 2733 { 2734 struct virtnet_info *vi = netdev_priv(dev); 2735 2736 return ethtool_virtdev_set_link_ksettings(dev, cmd, 2737 &vi->speed, &vi->duplex); 2738 } 2739 2740 static int virtnet_get_link_ksettings(struct net_device *dev, 2741 struct ethtool_link_ksettings *cmd) 2742 { 2743 struct virtnet_info *vi = netdev_priv(dev); 2744 2745 cmd->base.speed = vi->speed; 2746 cmd->base.duplex = vi->duplex; 2747 cmd->base.port = PORT_OTHER; 2748 2749 return 0; 2750 } 2751 2752 static int virtnet_send_notf_coal_cmds(struct virtnet_info *vi, 2753 struct ethtool_coalesce *ec) 2754 { 2755 struct scatterlist sgs_tx, sgs_rx; 2756 struct virtio_net_ctrl_coal_tx coal_tx; 2757 struct virtio_net_ctrl_coal_rx coal_rx; 2758 2759 coal_tx.tx_usecs = cpu_to_le32(ec->tx_coalesce_usecs); 2760 coal_tx.tx_max_packets = cpu_to_le32(ec->tx_max_coalesced_frames); 2761 sg_init_one(&sgs_tx, &coal_tx, sizeof(coal_tx)); 2762 2763 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_NOTF_COAL, 2764 VIRTIO_NET_CTRL_NOTF_COAL_TX_SET, 2765 &sgs_tx)) 2766 return -EINVAL; 2767 2768 /* Save parameters */ 2769 vi->tx_usecs = ec->tx_coalesce_usecs; 2770 vi->tx_max_packets = ec->tx_max_coalesced_frames; 2771 2772 coal_rx.rx_usecs = cpu_to_le32(ec->rx_coalesce_usecs); 2773 coal_rx.rx_max_packets = cpu_to_le32(ec->rx_max_coalesced_frames); 2774 sg_init_one(&sgs_rx, &coal_rx, sizeof(coal_rx)); 2775 2776 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_NOTF_COAL, 2777 VIRTIO_NET_CTRL_NOTF_COAL_RX_SET, 2778 &sgs_rx)) 2779 return -EINVAL; 2780 2781 /* Save parameters */ 2782 vi->rx_usecs = ec->rx_coalesce_usecs; 2783 vi->rx_max_packets = ec->rx_max_coalesced_frames; 2784 2785 return 0; 2786 } 2787 2788 static int virtnet_coal_params_supported(struct ethtool_coalesce *ec) 2789 { 2790 /* usecs coalescing is supported only if VIRTIO_NET_F_NOTF_COAL 2791 * feature is negotiated. 2792 */ 2793 if (ec->rx_coalesce_usecs || ec->tx_coalesce_usecs) 2794 return -EOPNOTSUPP; 2795 2796 if (ec->tx_max_coalesced_frames > 1 || 2797 ec->rx_max_coalesced_frames != 1) 2798 return -EINVAL; 2799 2800 return 0; 2801 } 2802 2803 static int virtnet_set_coalesce(struct net_device *dev, 2804 struct ethtool_coalesce *ec, 2805 struct kernel_ethtool_coalesce *kernel_coal, 2806 struct netlink_ext_ack *extack) 2807 { 2808 struct virtnet_info *vi = netdev_priv(dev); 2809 int ret, i, napi_weight; 2810 bool update_napi = false; 2811 2812 /* Can't change NAPI weight if the link is up */ 2813 napi_weight = ec->tx_max_coalesced_frames ? NAPI_POLL_WEIGHT : 0; 2814 if (napi_weight ^ vi->sq[0].napi.weight) { 2815 if (dev->flags & IFF_UP) 2816 return -EBUSY; 2817 else 2818 update_napi = true; 2819 } 2820 2821 if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_NOTF_COAL)) 2822 ret = virtnet_send_notf_coal_cmds(vi, ec); 2823 else 2824 ret = virtnet_coal_params_supported(ec); 2825 2826 if (ret) 2827 return ret; 2828 2829 if (update_napi) { 2830 for (i = 0; i < vi->max_queue_pairs; i++) 2831 vi->sq[i].napi.weight = napi_weight; 2832 } 2833 2834 return ret; 2835 } 2836 2837 static int virtnet_get_coalesce(struct net_device *dev, 2838 struct ethtool_coalesce *ec, 2839 struct kernel_ethtool_coalesce *kernel_coal, 2840 struct netlink_ext_ack *extack) 2841 { 2842 struct virtnet_info *vi = netdev_priv(dev); 2843 2844 if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_NOTF_COAL)) { 2845 ec->rx_coalesce_usecs = vi->rx_usecs; 2846 ec->tx_coalesce_usecs = vi->tx_usecs; 2847 ec->tx_max_coalesced_frames = vi->tx_max_packets; 2848 ec->rx_max_coalesced_frames = vi->rx_max_packets; 2849 } else { 2850 ec->rx_max_coalesced_frames = 1; 2851 2852 if (vi->sq[0].napi.weight) 2853 ec->tx_max_coalesced_frames = 1; 2854 } 2855 2856 return 0; 2857 } 2858 2859 static void virtnet_init_settings(struct net_device *dev) 2860 { 2861 struct virtnet_info *vi = netdev_priv(dev); 2862 2863 vi->speed = SPEED_UNKNOWN; 2864 vi->duplex = DUPLEX_UNKNOWN; 2865 } 2866 2867 static void virtnet_update_settings(struct virtnet_info *vi) 2868 { 2869 u32 speed; 2870 u8 duplex; 2871 2872 if (!virtio_has_feature(vi->vdev, VIRTIO_NET_F_SPEED_DUPLEX)) 2873 return; 2874 2875 virtio_cread_le(vi->vdev, struct virtio_net_config, speed, &speed); 2876 2877 if (ethtool_validate_speed(speed)) 2878 vi->speed = speed; 2879 2880 virtio_cread_le(vi->vdev, struct virtio_net_config, duplex, &duplex); 2881 2882 if (ethtool_validate_duplex(duplex)) 2883 vi->duplex = duplex; 2884 } 2885 2886 static u32 virtnet_get_rxfh_key_size(struct net_device *dev) 2887 { 2888 return ((struct virtnet_info *)netdev_priv(dev))->rss_key_size; 2889 } 2890 2891 static u32 virtnet_get_rxfh_indir_size(struct net_device *dev) 2892 { 2893 return ((struct virtnet_info *)netdev_priv(dev))->rss_indir_table_size; 2894 } 2895 2896 static int virtnet_get_rxfh(struct net_device *dev, u32 *indir, u8 *key, u8 *hfunc) 2897 { 2898 struct virtnet_info *vi = netdev_priv(dev); 2899 int i; 2900 2901 if (indir) { 2902 for (i = 0; i < vi->rss_indir_table_size; ++i) 2903 indir[i] = vi->ctrl->rss.indirection_table[i]; 2904 } 2905 2906 if (key) 2907 memcpy(key, vi->ctrl->rss.key, vi->rss_key_size); 2908 2909 if (hfunc) 2910 *hfunc = ETH_RSS_HASH_TOP; 2911 2912 return 0; 2913 } 2914 2915 static int virtnet_set_rxfh(struct net_device *dev, const u32 *indir, const u8 *key, const u8 hfunc) 2916 { 2917 struct virtnet_info *vi = netdev_priv(dev); 2918 int i; 2919 2920 if (hfunc != ETH_RSS_HASH_NO_CHANGE && hfunc != ETH_RSS_HASH_TOP) 2921 return -EOPNOTSUPP; 2922 2923 if (indir) { 2924 for (i = 0; i < vi->rss_indir_table_size; ++i) 2925 vi->ctrl->rss.indirection_table[i] = indir[i]; 2926 } 2927 if (key) 2928 memcpy(vi->ctrl->rss.key, key, vi->rss_key_size); 2929 2930 virtnet_commit_rss_command(vi); 2931 2932 return 0; 2933 } 2934 2935 static int virtnet_get_rxnfc(struct net_device *dev, struct ethtool_rxnfc *info, u32 *rule_locs) 2936 { 2937 struct virtnet_info *vi = netdev_priv(dev); 2938 int rc = 0; 2939 2940 switch (info->cmd) { 2941 case ETHTOOL_GRXRINGS: 2942 info->data = vi->curr_queue_pairs; 2943 break; 2944 case ETHTOOL_GRXFH: 2945 virtnet_get_hashflow(vi, info); 2946 break; 2947 default: 2948 rc = -EOPNOTSUPP; 2949 } 2950 2951 return rc; 2952 } 2953 2954 static int virtnet_set_rxnfc(struct net_device *dev, struct ethtool_rxnfc *info) 2955 { 2956 struct virtnet_info *vi = netdev_priv(dev); 2957 int rc = 0; 2958 2959 switch (info->cmd) { 2960 case ETHTOOL_SRXFH: 2961 if (!virtnet_set_hashflow(vi, info)) 2962 rc = -EINVAL; 2963 2964 break; 2965 default: 2966 rc = -EOPNOTSUPP; 2967 } 2968 2969 return rc; 2970 } 2971 2972 static const struct ethtool_ops virtnet_ethtool_ops = { 2973 .supported_coalesce_params = ETHTOOL_COALESCE_MAX_FRAMES | 2974 ETHTOOL_COALESCE_USECS, 2975 .get_drvinfo = virtnet_get_drvinfo, 2976 .get_link = ethtool_op_get_link, 2977 .get_ringparam = virtnet_get_ringparam, 2978 .set_ringparam = virtnet_set_ringparam, 2979 .get_strings = virtnet_get_strings, 2980 .get_sset_count = virtnet_get_sset_count, 2981 .get_ethtool_stats = virtnet_get_ethtool_stats, 2982 .set_channels = virtnet_set_channels, 2983 .get_channels = virtnet_get_channels, 2984 .get_ts_info = ethtool_op_get_ts_info, 2985 .get_link_ksettings = virtnet_get_link_ksettings, 2986 .set_link_ksettings = virtnet_set_link_ksettings, 2987 .set_coalesce = virtnet_set_coalesce, 2988 .get_coalesce = virtnet_get_coalesce, 2989 .get_rxfh_key_size = virtnet_get_rxfh_key_size, 2990 .get_rxfh_indir_size = virtnet_get_rxfh_indir_size, 2991 .get_rxfh = virtnet_get_rxfh, 2992 .set_rxfh = virtnet_set_rxfh, 2993 .get_rxnfc = virtnet_get_rxnfc, 2994 .set_rxnfc = virtnet_set_rxnfc, 2995 }; 2996 2997 static void virtnet_freeze_down(struct virtio_device *vdev) 2998 { 2999 struct virtnet_info *vi = vdev->priv; 3000 3001 /* Make sure no work handler is accessing the device */ 3002 flush_work(&vi->config_work); 3003 3004 netif_tx_lock_bh(vi->dev); 3005 netif_device_detach(vi->dev); 3006 netif_tx_unlock_bh(vi->dev); 3007 if (netif_running(vi->dev)) 3008 virtnet_close(vi->dev); 3009 } 3010 3011 static int init_vqs(struct virtnet_info *vi); 3012 3013 static int virtnet_restore_up(struct virtio_device *vdev) 3014 { 3015 struct virtnet_info *vi = vdev->priv; 3016 int err; 3017 3018 err = init_vqs(vi); 3019 if (err) 3020 return err; 3021 3022 virtio_device_ready(vdev); 3023 3024 enable_delayed_refill(vi); 3025 3026 if (netif_running(vi->dev)) { 3027 err = virtnet_open(vi->dev); 3028 if (err) 3029 return err; 3030 } 3031 3032 netif_tx_lock_bh(vi->dev); 3033 netif_device_attach(vi->dev); 3034 netif_tx_unlock_bh(vi->dev); 3035 return err; 3036 } 3037 3038 static int virtnet_set_guest_offloads(struct virtnet_info *vi, u64 offloads) 3039 { 3040 struct scatterlist sg; 3041 vi->ctrl->offloads = cpu_to_virtio64(vi->vdev, offloads); 3042 3043 sg_init_one(&sg, &vi->ctrl->offloads, sizeof(vi->ctrl->offloads)); 3044 3045 if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_GUEST_OFFLOADS, 3046 VIRTIO_NET_CTRL_GUEST_OFFLOADS_SET, &sg)) { 3047 dev_warn(&vi->dev->dev, "Fail to set guest offload.\n"); 3048 return -EINVAL; 3049 } 3050 3051 return 0; 3052 } 3053 3054 static int virtnet_clear_guest_offloads(struct virtnet_info *vi) 3055 { 3056 u64 offloads = 0; 3057 3058 if (!vi->guest_offloads) 3059 return 0; 3060 3061 return virtnet_set_guest_offloads(vi, offloads); 3062 } 3063 3064 static int virtnet_restore_guest_offloads(struct virtnet_info *vi) 3065 { 3066 u64 offloads = vi->guest_offloads; 3067 3068 if (!vi->guest_offloads) 3069 return 0; 3070 3071 return virtnet_set_guest_offloads(vi, offloads); 3072 } 3073 3074 static int virtnet_xdp_set(struct net_device *dev, struct bpf_prog *prog, 3075 struct netlink_ext_ack *extack) 3076 { 3077 unsigned long int max_sz = PAGE_SIZE - sizeof(struct padded_vnet_hdr); 3078 struct virtnet_info *vi = netdev_priv(dev); 3079 struct bpf_prog *old_prog; 3080 u16 xdp_qp = 0, curr_qp; 3081 int i, err; 3082 3083 if (!virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_GUEST_OFFLOADS) 3084 && (virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_TSO4) || 3085 virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_TSO6) || 3086 virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_ECN) || 3087 virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_UFO) || 3088 virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_CSUM))) { 3089 NL_SET_ERR_MSG_MOD(extack, "Can't set XDP while host is implementing GRO_HW/CSUM, disable GRO_HW/CSUM first"); 3090 return -EOPNOTSUPP; 3091 } 3092 3093 if (vi->mergeable_rx_bufs && !vi->any_header_sg) { 3094 NL_SET_ERR_MSG_MOD(extack, "XDP expects header/data in single page, any_header_sg required"); 3095 return -EINVAL; 3096 } 3097 3098 if (dev->mtu > max_sz) { 3099 NL_SET_ERR_MSG_MOD(extack, "MTU too large to enable XDP"); 3100 netdev_warn(dev, "XDP requires MTU less than %lu\n", max_sz); 3101 return -EINVAL; 3102 } 3103 3104 curr_qp = vi->curr_queue_pairs - vi->xdp_queue_pairs; 3105 if (prog) 3106 xdp_qp = nr_cpu_ids; 3107 3108 /* XDP requires extra queues for XDP_TX */ 3109 if (curr_qp + xdp_qp > vi->max_queue_pairs) { 3110 netdev_warn_once(dev, "XDP request %i queues but max is %i. XDP_TX and XDP_REDIRECT will operate in a slower locked tx mode.\n", 3111 curr_qp + xdp_qp, vi->max_queue_pairs); 3112 xdp_qp = 0; 3113 } 3114 3115 old_prog = rtnl_dereference(vi->rq[0].xdp_prog); 3116 if (!prog && !old_prog) 3117 return 0; 3118 3119 if (prog) 3120 bpf_prog_add(prog, vi->max_queue_pairs - 1); 3121 3122 /* Make sure NAPI is not using any XDP TX queues for RX. */ 3123 if (netif_running(dev)) { 3124 for (i = 0; i < vi->max_queue_pairs; i++) { 3125 napi_disable(&vi->rq[i].napi); 3126 virtnet_napi_tx_disable(&vi->sq[i].napi); 3127 } 3128 } 3129 3130 if (!prog) { 3131 for (i = 0; i < vi->max_queue_pairs; i++) { 3132 rcu_assign_pointer(vi->rq[i].xdp_prog, prog); 3133 if (i == 0) 3134 virtnet_restore_guest_offloads(vi); 3135 } 3136 synchronize_net(); 3137 } 3138 3139 err = _virtnet_set_queues(vi, curr_qp + xdp_qp); 3140 if (err) 3141 goto err; 3142 netif_set_real_num_rx_queues(dev, curr_qp + xdp_qp); 3143 vi->xdp_queue_pairs = xdp_qp; 3144 3145 if (prog) { 3146 vi->xdp_enabled = true; 3147 for (i = 0; i < vi->max_queue_pairs; i++) { 3148 rcu_assign_pointer(vi->rq[i].xdp_prog, prog); 3149 if (i == 0 && !old_prog) 3150 virtnet_clear_guest_offloads(vi); 3151 } 3152 } else { 3153 vi->xdp_enabled = false; 3154 } 3155 3156 for (i = 0; i < vi->max_queue_pairs; i++) { 3157 if (old_prog) 3158 bpf_prog_put(old_prog); 3159 if (netif_running(dev)) { 3160 virtnet_napi_enable(vi->rq[i].vq, &vi->rq[i].napi); 3161 virtnet_napi_tx_enable(vi, vi->sq[i].vq, 3162 &vi->sq[i].napi); 3163 } 3164 } 3165 3166 return 0; 3167 3168 err: 3169 if (!prog) { 3170 virtnet_clear_guest_offloads(vi); 3171 for (i = 0; i < vi->max_queue_pairs; i++) 3172 rcu_assign_pointer(vi->rq[i].xdp_prog, old_prog); 3173 } 3174 3175 if (netif_running(dev)) { 3176 for (i = 0; i < vi->max_queue_pairs; i++) { 3177 virtnet_napi_enable(vi->rq[i].vq, &vi->rq[i].napi); 3178 virtnet_napi_tx_enable(vi, vi->sq[i].vq, 3179 &vi->sq[i].napi); 3180 } 3181 } 3182 if (prog) 3183 bpf_prog_sub(prog, vi->max_queue_pairs - 1); 3184 return err; 3185 } 3186 3187 static int virtnet_xdp(struct net_device *dev, struct netdev_bpf *xdp) 3188 { 3189 switch (xdp->command) { 3190 case XDP_SETUP_PROG: 3191 return virtnet_xdp_set(dev, xdp->prog, xdp->extack); 3192 default: 3193 return -EINVAL; 3194 } 3195 } 3196 3197 static int virtnet_get_phys_port_name(struct net_device *dev, char *buf, 3198 size_t len) 3199 { 3200 struct virtnet_info *vi = netdev_priv(dev); 3201 int ret; 3202 3203 if (!virtio_has_feature(vi->vdev, VIRTIO_NET_F_STANDBY)) 3204 return -EOPNOTSUPP; 3205 3206 ret = snprintf(buf, len, "sby"); 3207 if (ret >= len) 3208 return -EOPNOTSUPP; 3209 3210 return 0; 3211 } 3212 3213 static int virtnet_set_features(struct net_device *dev, 3214 netdev_features_t features) 3215 { 3216 struct virtnet_info *vi = netdev_priv(dev); 3217 u64 offloads; 3218 int err; 3219 3220 if ((dev->features ^ features) & NETIF_F_GRO_HW) { 3221 if (vi->xdp_enabled) 3222 return -EBUSY; 3223 3224 if (features & NETIF_F_GRO_HW) 3225 offloads = vi->guest_offloads_capable; 3226 else 3227 offloads = vi->guest_offloads_capable & 3228 ~GUEST_OFFLOAD_GRO_HW_MASK; 3229 3230 err = virtnet_set_guest_offloads(vi, offloads); 3231 if (err) 3232 return err; 3233 vi->guest_offloads = offloads; 3234 } 3235 3236 if ((dev->features ^ features) & NETIF_F_RXHASH) { 3237 if (features & NETIF_F_RXHASH) 3238 vi->ctrl->rss.hash_types = vi->rss_hash_types_saved; 3239 else 3240 vi->ctrl->rss.hash_types = VIRTIO_NET_HASH_REPORT_NONE; 3241 3242 if (!virtnet_commit_rss_command(vi)) 3243 return -EINVAL; 3244 } 3245 3246 return 0; 3247 } 3248 3249 static void virtnet_tx_timeout(struct net_device *dev, unsigned int txqueue) 3250 { 3251 struct virtnet_info *priv = netdev_priv(dev); 3252 struct send_queue *sq = &priv->sq[txqueue]; 3253 struct netdev_queue *txq = netdev_get_tx_queue(dev, txqueue); 3254 3255 u64_stats_update_begin(&sq->stats.syncp); 3256 sq->stats.tx_timeouts++; 3257 u64_stats_update_end(&sq->stats.syncp); 3258 3259 netdev_err(dev, "TX timeout on queue: %u, sq: %s, vq: 0x%x, name: %s, %u usecs ago\n", 3260 txqueue, sq->name, sq->vq->index, sq->vq->name, 3261 jiffies_to_usecs(jiffies - READ_ONCE(txq->trans_start))); 3262 } 3263 3264 static const struct net_device_ops virtnet_netdev = { 3265 .ndo_open = virtnet_open, 3266 .ndo_stop = virtnet_close, 3267 .ndo_start_xmit = start_xmit, 3268 .ndo_validate_addr = eth_validate_addr, 3269 .ndo_set_mac_address = virtnet_set_mac_address, 3270 .ndo_set_rx_mode = virtnet_set_rx_mode, 3271 .ndo_get_stats64 = virtnet_stats, 3272 .ndo_vlan_rx_add_vid = virtnet_vlan_rx_add_vid, 3273 .ndo_vlan_rx_kill_vid = virtnet_vlan_rx_kill_vid, 3274 .ndo_bpf = virtnet_xdp, 3275 .ndo_xdp_xmit = virtnet_xdp_xmit, 3276 .ndo_features_check = passthru_features_check, 3277 .ndo_get_phys_port_name = virtnet_get_phys_port_name, 3278 .ndo_set_features = virtnet_set_features, 3279 .ndo_tx_timeout = virtnet_tx_timeout, 3280 }; 3281 3282 static void virtnet_config_changed_work(struct work_struct *work) 3283 { 3284 struct virtnet_info *vi = 3285 container_of(work, struct virtnet_info, config_work); 3286 u16 v; 3287 3288 if (virtio_cread_feature(vi->vdev, VIRTIO_NET_F_STATUS, 3289 struct virtio_net_config, status, &v) < 0) 3290 return; 3291 3292 if (v & VIRTIO_NET_S_ANNOUNCE) { 3293 netdev_notify_peers(vi->dev); 3294 virtnet_ack_link_announce(vi); 3295 } 3296 3297 /* Ignore unknown (future) status bits */ 3298 v &= VIRTIO_NET_S_LINK_UP; 3299 3300 if (vi->status == v) 3301 return; 3302 3303 vi->status = v; 3304 3305 if (vi->status & VIRTIO_NET_S_LINK_UP) { 3306 virtnet_update_settings(vi); 3307 netif_carrier_on(vi->dev); 3308 netif_tx_wake_all_queues(vi->dev); 3309 } else { 3310 netif_carrier_off(vi->dev); 3311 netif_tx_stop_all_queues(vi->dev); 3312 } 3313 } 3314 3315 static void virtnet_config_changed(struct virtio_device *vdev) 3316 { 3317 struct virtnet_info *vi = vdev->priv; 3318 3319 schedule_work(&vi->config_work); 3320 } 3321 3322 static void virtnet_free_queues(struct virtnet_info *vi) 3323 { 3324 int i; 3325 3326 for (i = 0; i < vi->max_queue_pairs; i++) { 3327 __netif_napi_del(&vi->rq[i].napi); 3328 __netif_napi_del(&vi->sq[i].napi); 3329 } 3330 3331 /* We called __netif_napi_del(), 3332 * we need to respect an RCU grace period before freeing vi->rq 3333 */ 3334 synchronize_net(); 3335 3336 kfree(vi->rq); 3337 kfree(vi->sq); 3338 kfree(vi->ctrl); 3339 } 3340 3341 static void _free_receive_bufs(struct virtnet_info *vi) 3342 { 3343 struct bpf_prog *old_prog; 3344 int i; 3345 3346 for (i = 0; i < vi->max_queue_pairs; i++) { 3347 while (vi->rq[i].pages) 3348 __free_pages(get_a_page(&vi->rq[i], GFP_KERNEL), 0); 3349 3350 old_prog = rtnl_dereference(vi->rq[i].xdp_prog); 3351 RCU_INIT_POINTER(vi->rq[i].xdp_prog, NULL); 3352 if (old_prog) 3353 bpf_prog_put(old_prog); 3354 } 3355 } 3356 3357 static void free_receive_bufs(struct virtnet_info *vi) 3358 { 3359 rtnl_lock(); 3360 _free_receive_bufs(vi); 3361 rtnl_unlock(); 3362 } 3363 3364 static void free_receive_page_frags(struct virtnet_info *vi) 3365 { 3366 int i; 3367 for (i = 0; i < vi->max_queue_pairs; i++) 3368 if (vi->rq[i].alloc_frag.page) 3369 put_page(vi->rq[i].alloc_frag.page); 3370 } 3371 3372 static void virtnet_sq_free_unused_buf(struct virtqueue *vq, void *buf) 3373 { 3374 if (!is_xdp_frame(buf)) 3375 dev_kfree_skb(buf); 3376 else 3377 xdp_return_frame(ptr_to_xdp(buf)); 3378 } 3379 3380 static void virtnet_rq_free_unused_buf(struct virtqueue *vq, void *buf) 3381 { 3382 struct virtnet_info *vi = vq->vdev->priv; 3383 int i = vq2rxq(vq); 3384 3385 if (vi->mergeable_rx_bufs) 3386 put_page(virt_to_head_page(buf)); 3387 else if (vi->big_packets) 3388 give_pages(&vi->rq[i], buf); 3389 else 3390 put_page(virt_to_head_page(buf)); 3391 } 3392 3393 static void free_unused_bufs(struct virtnet_info *vi) 3394 { 3395 void *buf; 3396 int i; 3397 3398 for (i = 0; i < vi->max_queue_pairs; i++) { 3399 struct virtqueue *vq = vi->sq[i].vq; 3400 while ((buf = virtqueue_detach_unused_buf(vq)) != NULL) 3401 virtnet_sq_free_unused_buf(vq, buf); 3402 } 3403 3404 for (i = 0; i < vi->max_queue_pairs; i++) { 3405 struct virtqueue *vq = vi->rq[i].vq; 3406 while ((buf = virtqueue_detach_unused_buf(vq)) != NULL) 3407 virtnet_rq_free_unused_buf(vq, buf); 3408 } 3409 } 3410 3411 static void virtnet_del_vqs(struct virtnet_info *vi) 3412 { 3413 struct virtio_device *vdev = vi->vdev; 3414 3415 virtnet_clean_affinity(vi); 3416 3417 vdev->config->del_vqs(vdev); 3418 3419 virtnet_free_queues(vi); 3420 } 3421 3422 /* How large should a single buffer be so a queue full of these can fit at 3423 * least one full packet? 3424 * Logic below assumes the mergeable buffer header is used. 3425 */ 3426 static unsigned int mergeable_min_buf_len(struct virtnet_info *vi, struct virtqueue *vq) 3427 { 3428 const unsigned int hdr_len = vi->hdr_len; 3429 unsigned int rq_size = virtqueue_get_vring_size(vq); 3430 unsigned int packet_len = vi->big_packets ? IP_MAX_MTU : vi->dev->max_mtu; 3431 unsigned int buf_len = hdr_len + ETH_HLEN + VLAN_HLEN + packet_len; 3432 unsigned int min_buf_len = DIV_ROUND_UP(buf_len, rq_size); 3433 3434 return max(max(min_buf_len, hdr_len) - hdr_len, 3435 (unsigned int)GOOD_PACKET_LEN); 3436 } 3437 3438 static int virtnet_find_vqs(struct virtnet_info *vi) 3439 { 3440 vq_callback_t **callbacks; 3441 struct virtqueue **vqs; 3442 int ret = -ENOMEM; 3443 int i, total_vqs; 3444 const char **names; 3445 bool *ctx; 3446 3447 /* We expect 1 RX virtqueue followed by 1 TX virtqueue, followed by 3448 * possible N-1 RX/TX queue pairs used in multiqueue mode, followed by 3449 * possible control vq. 3450 */ 3451 total_vqs = vi->max_queue_pairs * 2 + 3452 virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ); 3453 3454 /* Allocate space for find_vqs parameters */ 3455 vqs = kcalloc(total_vqs, sizeof(*vqs), GFP_KERNEL); 3456 if (!vqs) 3457 goto err_vq; 3458 callbacks = kmalloc_array(total_vqs, sizeof(*callbacks), GFP_KERNEL); 3459 if (!callbacks) 3460 goto err_callback; 3461 names = kmalloc_array(total_vqs, sizeof(*names), GFP_KERNEL); 3462 if (!names) 3463 goto err_names; 3464 if (!vi->big_packets || vi->mergeable_rx_bufs) { 3465 ctx = kcalloc(total_vqs, sizeof(*ctx), GFP_KERNEL); 3466 if (!ctx) 3467 goto err_ctx; 3468 } else { 3469 ctx = NULL; 3470 } 3471 3472 /* Parameters for control virtqueue, if any */ 3473 if (vi->has_cvq) { 3474 callbacks[total_vqs - 1] = NULL; 3475 names[total_vqs - 1] = "control"; 3476 } 3477 3478 /* Allocate/initialize parameters for send/receive virtqueues */ 3479 for (i = 0; i < vi->max_queue_pairs; i++) { 3480 callbacks[rxq2vq(i)] = skb_recv_done; 3481 callbacks[txq2vq(i)] = skb_xmit_done; 3482 sprintf(vi->rq[i].name, "input.%d", i); 3483 sprintf(vi->sq[i].name, "output.%d", i); 3484 names[rxq2vq(i)] = vi->rq[i].name; 3485 names[txq2vq(i)] = vi->sq[i].name; 3486 if (ctx) 3487 ctx[rxq2vq(i)] = true; 3488 } 3489 3490 ret = virtio_find_vqs_ctx(vi->vdev, total_vqs, vqs, callbacks, 3491 names, ctx, NULL); 3492 if (ret) 3493 goto err_find; 3494 3495 if (vi->has_cvq) { 3496 vi->cvq = vqs[total_vqs - 1]; 3497 if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VLAN)) 3498 vi->dev->features |= NETIF_F_HW_VLAN_CTAG_FILTER; 3499 } 3500 3501 for (i = 0; i < vi->max_queue_pairs; i++) { 3502 vi->rq[i].vq = vqs[rxq2vq(i)]; 3503 vi->rq[i].min_buf_len = mergeable_min_buf_len(vi, vi->rq[i].vq); 3504 vi->sq[i].vq = vqs[txq2vq(i)]; 3505 } 3506 3507 /* run here: ret == 0. */ 3508 3509 3510 err_find: 3511 kfree(ctx); 3512 err_ctx: 3513 kfree(names); 3514 err_names: 3515 kfree(callbacks); 3516 err_callback: 3517 kfree(vqs); 3518 err_vq: 3519 return ret; 3520 } 3521 3522 static int virtnet_alloc_queues(struct virtnet_info *vi) 3523 { 3524 int i; 3525 3526 if (vi->has_cvq) { 3527 vi->ctrl = kzalloc(sizeof(*vi->ctrl), GFP_KERNEL); 3528 if (!vi->ctrl) 3529 goto err_ctrl; 3530 } else { 3531 vi->ctrl = NULL; 3532 } 3533 vi->sq = kcalloc(vi->max_queue_pairs, sizeof(*vi->sq), GFP_KERNEL); 3534 if (!vi->sq) 3535 goto err_sq; 3536 vi->rq = kcalloc(vi->max_queue_pairs, sizeof(*vi->rq), GFP_KERNEL); 3537 if (!vi->rq) 3538 goto err_rq; 3539 3540 INIT_DELAYED_WORK(&vi->refill, refill_work); 3541 for (i = 0; i < vi->max_queue_pairs; i++) { 3542 vi->rq[i].pages = NULL; 3543 netif_napi_add_weight(vi->dev, &vi->rq[i].napi, virtnet_poll, 3544 napi_weight); 3545 netif_napi_add_tx_weight(vi->dev, &vi->sq[i].napi, 3546 virtnet_poll_tx, 3547 napi_tx ? napi_weight : 0); 3548 3549 sg_init_table(vi->rq[i].sg, ARRAY_SIZE(vi->rq[i].sg)); 3550 ewma_pkt_len_init(&vi->rq[i].mrg_avg_pkt_len); 3551 sg_init_table(vi->sq[i].sg, ARRAY_SIZE(vi->sq[i].sg)); 3552 3553 u64_stats_init(&vi->rq[i].stats.syncp); 3554 u64_stats_init(&vi->sq[i].stats.syncp); 3555 } 3556 3557 return 0; 3558 3559 err_rq: 3560 kfree(vi->sq); 3561 err_sq: 3562 kfree(vi->ctrl); 3563 err_ctrl: 3564 return -ENOMEM; 3565 } 3566 3567 static int init_vqs(struct virtnet_info *vi) 3568 { 3569 int ret; 3570 3571 /* Allocate send & receive queues */ 3572 ret = virtnet_alloc_queues(vi); 3573 if (ret) 3574 goto err; 3575 3576 ret = virtnet_find_vqs(vi); 3577 if (ret) 3578 goto err_free; 3579 3580 cpus_read_lock(); 3581 virtnet_set_affinity(vi); 3582 cpus_read_unlock(); 3583 3584 return 0; 3585 3586 err_free: 3587 virtnet_free_queues(vi); 3588 err: 3589 return ret; 3590 } 3591 3592 #ifdef CONFIG_SYSFS 3593 static ssize_t mergeable_rx_buffer_size_show(struct netdev_rx_queue *queue, 3594 char *buf) 3595 { 3596 struct virtnet_info *vi = netdev_priv(queue->dev); 3597 unsigned int queue_index = get_netdev_rx_queue_index(queue); 3598 unsigned int headroom = virtnet_get_headroom(vi); 3599 unsigned int tailroom = headroom ? sizeof(struct skb_shared_info) : 0; 3600 struct ewma_pkt_len *avg; 3601 3602 BUG_ON(queue_index >= vi->max_queue_pairs); 3603 avg = &vi->rq[queue_index].mrg_avg_pkt_len; 3604 return sprintf(buf, "%u\n", 3605 get_mergeable_buf_len(&vi->rq[queue_index], avg, 3606 SKB_DATA_ALIGN(headroom + tailroom))); 3607 } 3608 3609 static struct rx_queue_attribute mergeable_rx_buffer_size_attribute = 3610 __ATTR_RO(mergeable_rx_buffer_size); 3611 3612 static struct attribute *virtio_net_mrg_rx_attrs[] = { 3613 &mergeable_rx_buffer_size_attribute.attr, 3614 NULL 3615 }; 3616 3617 static const struct attribute_group virtio_net_mrg_rx_group = { 3618 .name = "virtio_net", 3619 .attrs = virtio_net_mrg_rx_attrs 3620 }; 3621 #endif 3622 3623 static bool virtnet_fail_on_feature(struct virtio_device *vdev, 3624 unsigned int fbit, 3625 const char *fname, const char *dname) 3626 { 3627 if (!virtio_has_feature(vdev, fbit)) 3628 return false; 3629 3630 dev_err(&vdev->dev, "device advertises feature %s but not %s", 3631 fname, dname); 3632 3633 return true; 3634 } 3635 3636 #define VIRTNET_FAIL_ON(vdev, fbit, dbit) \ 3637 virtnet_fail_on_feature(vdev, fbit, #fbit, dbit) 3638 3639 static bool virtnet_validate_features(struct virtio_device *vdev) 3640 { 3641 if (!virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_VQ) && 3642 (VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_CTRL_RX, 3643 "VIRTIO_NET_F_CTRL_VQ") || 3644 VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_CTRL_VLAN, 3645 "VIRTIO_NET_F_CTRL_VQ") || 3646 VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_GUEST_ANNOUNCE, 3647 "VIRTIO_NET_F_CTRL_VQ") || 3648 VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_MQ, "VIRTIO_NET_F_CTRL_VQ") || 3649 VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_CTRL_MAC_ADDR, 3650 "VIRTIO_NET_F_CTRL_VQ") || 3651 VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_RSS, 3652 "VIRTIO_NET_F_CTRL_VQ") || 3653 VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_HASH_REPORT, 3654 "VIRTIO_NET_F_CTRL_VQ") || 3655 VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_NOTF_COAL, 3656 "VIRTIO_NET_F_CTRL_VQ"))) { 3657 return false; 3658 } 3659 3660 return true; 3661 } 3662 3663 #define MIN_MTU ETH_MIN_MTU 3664 #define MAX_MTU ETH_MAX_MTU 3665 3666 static int virtnet_validate(struct virtio_device *vdev) 3667 { 3668 if (!vdev->config->get) { 3669 dev_err(&vdev->dev, "%s failure: config access disabled\n", 3670 __func__); 3671 return -EINVAL; 3672 } 3673 3674 if (!virtnet_validate_features(vdev)) 3675 return -EINVAL; 3676 3677 if (virtio_has_feature(vdev, VIRTIO_NET_F_MTU)) { 3678 int mtu = virtio_cread16(vdev, 3679 offsetof(struct virtio_net_config, 3680 mtu)); 3681 if (mtu < MIN_MTU) 3682 __virtio_clear_bit(vdev, VIRTIO_NET_F_MTU); 3683 } 3684 3685 return 0; 3686 } 3687 3688 static bool virtnet_check_guest_gso(const struct virtnet_info *vi) 3689 { 3690 return virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_TSO4) || 3691 virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_TSO6) || 3692 virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_ECN) || 3693 virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_UFO); 3694 } 3695 3696 static void virtnet_set_big_packets(struct virtnet_info *vi, const int mtu) 3697 { 3698 bool guest_gso = virtnet_check_guest_gso(vi); 3699 3700 /* If device can receive ANY guest GSO packets, regardless of mtu, 3701 * allocate packets of maximum size, otherwise limit it to only 3702 * mtu size worth only. 3703 */ 3704 if (mtu > ETH_DATA_LEN || guest_gso) { 3705 vi->big_packets = true; 3706 vi->big_packets_num_skbfrags = guest_gso ? MAX_SKB_FRAGS : DIV_ROUND_UP(mtu, PAGE_SIZE); 3707 } 3708 } 3709 3710 static int virtnet_probe(struct virtio_device *vdev) 3711 { 3712 int i, err = -ENOMEM; 3713 struct net_device *dev; 3714 struct virtnet_info *vi; 3715 u16 max_queue_pairs; 3716 int mtu = 0; 3717 3718 /* Find if host supports multiqueue/rss virtio_net device */ 3719 max_queue_pairs = 1; 3720 if (virtio_has_feature(vdev, VIRTIO_NET_F_MQ) || virtio_has_feature(vdev, VIRTIO_NET_F_RSS)) 3721 max_queue_pairs = 3722 virtio_cread16(vdev, offsetof(struct virtio_net_config, max_virtqueue_pairs)); 3723 3724 /* We need at least 2 queue's */ 3725 if (max_queue_pairs < VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MIN || 3726 max_queue_pairs > VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MAX || 3727 !virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_VQ)) 3728 max_queue_pairs = 1; 3729 3730 /* Allocate ourselves a network device with room for our info */ 3731 dev = alloc_etherdev_mq(sizeof(struct virtnet_info), max_queue_pairs); 3732 if (!dev) 3733 return -ENOMEM; 3734 3735 /* Set up network device as normal. */ 3736 dev->priv_flags |= IFF_UNICAST_FLT | IFF_LIVE_ADDR_CHANGE | 3737 IFF_TX_SKB_NO_LINEAR; 3738 dev->netdev_ops = &virtnet_netdev; 3739 dev->features = NETIF_F_HIGHDMA; 3740 3741 dev->ethtool_ops = &virtnet_ethtool_ops; 3742 SET_NETDEV_DEV(dev, &vdev->dev); 3743 3744 /* Do we support "hardware" checksums? */ 3745 if (virtio_has_feature(vdev, VIRTIO_NET_F_CSUM)) { 3746 /* This opens up the world of extra features. */ 3747 dev->hw_features |= NETIF_F_HW_CSUM | NETIF_F_SG; 3748 if (csum) 3749 dev->features |= NETIF_F_HW_CSUM | NETIF_F_SG; 3750 3751 if (virtio_has_feature(vdev, VIRTIO_NET_F_GSO)) { 3752 dev->hw_features |= NETIF_F_TSO 3753 | NETIF_F_TSO_ECN | NETIF_F_TSO6; 3754 } 3755 /* Individual feature bits: what can host handle? */ 3756 if (virtio_has_feature(vdev, VIRTIO_NET_F_HOST_TSO4)) 3757 dev->hw_features |= NETIF_F_TSO; 3758 if (virtio_has_feature(vdev, VIRTIO_NET_F_HOST_TSO6)) 3759 dev->hw_features |= NETIF_F_TSO6; 3760 if (virtio_has_feature(vdev, VIRTIO_NET_F_HOST_ECN)) 3761 dev->hw_features |= NETIF_F_TSO_ECN; 3762 3763 dev->features |= NETIF_F_GSO_ROBUST; 3764 3765 if (gso) 3766 dev->features |= dev->hw_features & NETIF_F_ALL_TSO; 3767 /* (!csum && gso) case will be fixed by register_netdev() */ 3768 } 3769 if (virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_CSUM)) 3770 dev->features |= NETIF_F_RXCSUM; 3771 if (virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_TSO4) || 3772 virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_TSO6)) 3773 dev->features |= NETIF_F_GRO_HW; 3774 if (virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_GUEST_OFFLOADS)) 3775 dev->hw_features |= NETIF_F_GRO_HW; 3776 3777 dev->vlan_features = dev->features; 3778 3779 /* MTU range: 68 - 65535 */ 3780 dev->min_mtu = MIN_MTU; 3781 dev->max_mtu = MAX_MTU; 3782 3783 /* Configuration may specify what MAC to use. Otherwise random. */ 3784 if (virtio_has_feature(vdev, VIRTIO_NET_F_MAC)) { 3785 u8 addr[ETH_ALEN]; 3786 3787 virtio_cread_bytes(vdev, 3788 offsetof(struct virtio_net_config, mac), 3789 addr, ETH_ALEN); 3790 eth_hw_addr_set(dev, addr); 3791 } else { 3792 eth_hw_addr_random(dev); 3793 } 3794 3795 /* Set up our device-specific information */ 3796 vi = netdev_priv(dev); 3797 vi->dev = dev; 3798 vi->vdev = vdev; 3799 vdev->priv = vi; 3800 3801 INIT_WORK(&vi->config_work, virtnet_config_changed_work); 3802 spin_lock_init(&vi->refill_lock); 3803 3804 if (virtio_has_feature(vdev, VIRTIO_NET_F_MRG_RXBUF)) 3805 vi->mergeable_rx_bufs = true; 3806 3807 if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_NOTF_COAL)) { 3808 vi->rx_usecs = 0; 3809 vi->tx_usecs = 0; 3810 vi->tx_max_packets = 0; 3811 vi->rx_max_packets = 0; 3812 } 3813 3814 if (virtio_has_feature(vdev, VIRTIO_NET_F_HASH_REPORT)) 3815 vi->has_rss_hash_report = true; 3816 3817 if (virtio_has_feature(vdev, VIRTIO_NET_F_RSS)) 3818 vi->has_rss = true; 3819 3820 if (vi->has_rss || vi->has_rss_hash_report) { 3821 vi->rss_indir_table_size = 3822 virtio_cread16(vdev, offsetof(struct virtio_net_config, 3823 rss_max_indirection_table_length)); 3824 vi->rss_key_size = 3825 virtio_cread8(vdev, offsetof(struct virtio_net_config, rss_max_key_size)); 3826 3827 vi->rss_hash_types_supported = 3828 virtio_cread32(vdev, offsetof(struct virtio_net_config, supported_hash_types)); 3829 vi->rss_hash_types_supported &= 3830 ~(VIRTIO_NET_RSS_HASH_TYPE_IP_EX | 3831 VIRTIO_NET_RSS_HASH_TYPE_TCP_EX | 3832 VIRTIO_NET_RSS_HASH_TYPE_UDP_EX); 3833 3834 dev->hw_features |= NETIF_F_RXHASH; 3835 } 3836 3837 if (vi->has_rss_hash_report) 3838 vi->hdr_len = sizeof(struct virtio_net_hdr_v1_hash); 3839 else if (virtio_has_feature(vdev, VIRTIO_NET_F_MRG_RXBUF) || 3840 virtio_has_feature(vdev, VIRTIO_F_VERSION_1)) 3841 vi->hdr_len = sizeof(struct virtio_net_hdr_mrg_rxbuf); 3842 else 3843 vi->hdr_len = sizeof(struct virtio_net_hdr); 3844 3845 if (virtio_has_feature(vdev, VIRTIO_F_ANY_LAYOUT) || 3846 virtio_has_feature(vdev, VIRTIO_F_VERSION_1)) 3847 vi->any_header_sg = true; 3848 3849 if (virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_VQ)) 3850 vi->has_cvq = true; 3851 3852 if (virtio_has_feature(vdev, VIRTIO_NET_F_MTU)) { 3853 mtu = virtio_cread16(vdev, 3854 offsetof(struct virtio_net_config, 3855 mtu)); 3856 if (mtu < dev->min_mtu) { 3857 /* Should never trigger: MTU was previously validated 3858 * in virtnet_validate. 3859 */ 3860 dev_err(&vdev->dev, 3861 "device MTU appears to have changed it is now %d < %d", 3862 mtu, dev->min_mtu); 3863 err = -EINVAL; 3864 goto free; 3865 } 3866 3867 dev->mtu = mtu; 3868 dev->max_mtu = mtu; 3869 } 3870 3871 virtnet_set_big_packets(vi, mtu); 3872 3873 if (vi->any_header_sg) 3874 dev->needed_headroom = vi->hdr_len; 3875 3876 /* Enable multiqueue by default */ 3877 if (num_online_cpus() >= max_queue_pairs) 3878 vi->curr_queue_pairs = max_queue_pairs; 3879 else 3880 vi->curr_queue_pairs = num_online_cpus(); 3881 vi->max_queue_pairs = max_queue_pairs; 3882 3883 /* Allocate/initialize the rx/tx queues, and invoke find_vqs */ 3884 err = init_vqs(vi); 3885 if (err) 3886 goto free; 3887 3888 #ifdef CONFIG_SYSFS 3889 if (vi->mergeable_rx_bufs) 3890 dev->sysfs_rx_queue_group = &virtio_net_mrg_rx_group; 3891 #endif 3892 netif_set_real_num_tx_queues(dev, vi->curr_queue_pairs); 3893 netif_set_real_num_rx_queues(dev, vi->curr_queue_pairs); 3894 3895 virtnet_init_settings(dev); 3896 3897 if (virtio_has_feature(vdev, VIRTIO_NET_F_STANDBY)) { 3898 vi->failover = net_failover_create(vi->dev); 3899 if (IS_ERR(vi->failover)) { 3900 err = PTR_ERR(vi->failover); 3901 goto free_vqs; 3902 } 3903 } 3904 3905 if (vi->has_rss || vi->has_rss_hash_report) 3906 virtnet_init_default_rss(vi); 3907 3908 /* serialize netdev register + virtio_device_ready() with ndo_open() */ 3909 rtnl_lock(); 3910 3911 err = register_netdevice(dev); 3912 if (err) { 3913 pr_debug("virtio_net: registering device failed\n"); 3914 rtnl_unlock(); 3915 goto free_failover; 3916 } 3917 3918 virtio_device_ready(vdev); 3919 3920 rtnl_unlock(); 3921 3922 err = virtnet_cpu_notif_add(vi); 3923 if (err) { 3924 pr_debug("virtio_net: registering cpu notifier failed\n"); 3925 goto free_unregister_netdev; 3926 } 3927 3928 virtnet_set_queues(vi, vi->curr_queue_pairs); 3929 3930 /* Assume link up if device can't report link status, 3931 otherwise get link status from config. */ 3932 netif_carrier_off(dev); 3933 if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_STATUS)) { 3934 schedule_work(&vi->config_work); 3935 } else { 3936 vi->status = VIRTIO_NET_S_LINK_UP; 3937 virtnet_update_settings(vi); 3938 netif_carrier_on(dev); 3939 } 3940 3941 for (i = 0; i < ARRAY_SIZE(guest_offloads); i++) 3942 if (virtio_has_feature(vi->vdev, guest_offloads[i])) 3943 set_bit(guest_offloads[i], &vi->guest_offloads); 3944 vi->guest_offloads_capable = vi->guest_offloads; 3945 3946 pr_debug("virtnet: registered device %s with %d RX and TX vq's\n", 3947 dev->name, max_queue_pairs); 3948 3949 return 0; 3950 3951 free_unregister_netdev: 3952 virtio_reset_device(vdev); 3953 3954 unregister_netdev(dev); 3955 free_failover: 3956 net_failover_destroy(vi->failover); 3957 free_vqs: 3958 cancel_delayed_work_sync(&vi->refill); 3959 free_receive_page_frags(vi); 3960 virtnet_del_vqs(vi); 3961 free: 3962 free_netdev(dev); 3963 return err; 3964 } 3965 3966 static void remove_vq_common(struct virtnet_info *vi) 3967 { 3968 virtio_reset_device(vi->vdev); 3969 3970 /* Free unused buffers in both send and recv, if any. */ 3971 free_unused_bufs(vi); 3972 3973 free_receive_bufs(vi); 3974 3975 free_receive_page_frags(vi); 3976 3977 virtnet_del_vqs(vi); 3978 } 3979 3980 static void virtnet_remove(struct virtio_device *vdev) 3981 { 3982 struct virtnet_info *vi = vdev->priv; 3983 3984 virtnet_cpu_notif_remove(vi); 3985 3986 /* Make sure no work handler is accessing the device. */ 3987 flush_work(&vi->config_work); 3988 3989 unregister_netdev(vi->dev); 3990 3991 net_failover_destroy(vi->failover); 3992 3993 remove_vq_common(vi); 3994 3995 free_netdev(vi->dev); 3996 } 3997 3998 static __maybe_unused int virtnet_freeze(struct virtio_device *vdev) 3999 { 4000 struct virtnet_info *vi = vdev->priv; 4001 4002 virtnet_cpu_notif_remove(vi); 4003 virtnet_freeze_down(vdev); 4004 remove_vq_common(vi); 4005 4006 return 0; 4007 } 4008 4009 static __maybe_unused int virtnet_restore(struct virtio_device *vdev) 4010 { 4011 struct virtnet_info *vi = vdev->priv; 4012 int err; 4013 4014 err = virtnet_restore_up(vdev); 4015 if (err) 4016 return err; 4017 virtnet_set_queues(vi, vi->curr_queue_pairs); 4018 4019 err = virtnet_cpu_notif_add(vi); 4020 if (err) { 4021 virtnet_freeze_down(vdev); 4022 remove_vq_common(vi); 4023 return err; 4024 } 4025 4026 return 0; 4027 } 4028 4029 static struct virtio_device_id id_table[] = { 4030 { VIRTIO_ID_NET, VIRTIO_DEV_ANY_ID }, 4031 { 0 }, 4032 }; 4033 4034 #define VIRTNET_FEATURES \ 4035 VIRTIO_NET_F_CSUM, VIRTIO_NET_F_GUEST_CSUM, \ 4036 VIRTIO_NET_F_MAC, \ 4037 VIRTIO_NET_F_HOST_TSO4, VIRTIO_NET_F_HOST_UFO, VIRTIO_NET_F_HOST_TSO6, \ 4038 VIRTIO_NET_F_HOST_ECN, VIRTIO_NET_F_GUEST_TSO4, VIRTIO_NET_F_GUEST_TSO6, \ 4039 VIRTIO_NET_F_GUEST_ECN, VIRTIO_NET_F_GUEST_UFO, \ 4040 VIRTIO_NET_F_MRG_RXBUF, VIRTIO_NET_F_STATUS, VIRTIO_NET_F_CTRL_VQ, \ 4041 VIRTIO_NET_F_CTRL_RX, VIRTIO_NET_F_CTRL_VLAN, \ 4042 VIRTIO_NET_F_GUEST_ANNOUNCE, VIRTIO_NET_F_MQ, \ 4043 VIRTIO_NET_F_CTRL_MAC_ADDR, \ 4044 VIRTIO_NET_F_MTU, VIRTIO_NET_F_CTRL_GUEST_OFFLOADS, \ 4045 VIRTIO_NET_F_SPEED_DUPLEX, VIRTIO_NET_F_STANDBY, \ 4046 VIRTIO_NET_F_RSS, VIRTIO_NET_F_HASH_REPORT, VIRTIO_NET_F_NOTF_COAL 4047 4048 static unsigned int features[] = { 4049 VIRTNET_FEATURES, 4050 }; 4051 4052 static unsigned int features_legacy[] = { 4053 VIRTNET_FEATURES, 4054 VIRTIO_NET_F_GSO, 4055 VIRTIO_F_ANY_LAYOUT, 4056 }; 4057 4058 static struct virtio_driver virtio_net_driver = { 4059 .feature_table = features, 4060 .feature_table_size = ARRAY_SIZE(features), 4061 .feature_table_legacy = features_legacy, 4062 .feature_table_size_legacy = ARRAY_SIZE(features_legacy), 4063 .driver.name = KBUILD_MODNAME, 4064 .driver.owner = THIS_MODULE, 4065 .id_table = id_table, 4066 .validate = virtnet_validate, 4067 .probe = virtnet_probe, 4068 .remove = virtnet_remove, 4069 .config_changed = virtnet_config_changed, 4070 #ifdef CONFIG_PM_SLEEP 4071 .freeze = virtnet_freeze, 4072 .restore = virtnet_restore, 4073 #endif 4074 }; 4075 4076 static __init int virtio_net_driver_init(void) 4077 { 4078 int ret; 4079 4080 ret = cpuhp_setup_state_multi(CPUHP_AP_ONLINE_DYN, "virtio/net:online", 4081 virtnet_cpu_online, 4082 virtnet_cpu_down_prep); 4083 if (ret < 0) 4084 goto out; 4085 virtionet_online = ret; 4086 ret = cpuhp_setup_state_multi(CPUHP_VIRT_NET_DEAD, "virtio/net:dead", 4087 NULL, virtnet_cpu_dead); 4088 if (ret) 4089 goto err_dead; 4090 ret = register_virtio_driver(&virtio_net_driver); 4091 if (ret) 4092 goto err_virtio; 4093 return 0; 4094 err_virtio: 4095 cpuhp_remove_multi_state(CPUHP_VIRT_NET_DEAD); 4096 err_dead: 4097 cpuhp_remove_multi_state(virtionet_online); 4098 out: 4099 return ret; 4100 } 4101 module_init(virtio_net_driver_init); 4102 4103 static __exit void virtio_net_driver_exit(void) 4104 { 4105 unregister_virtio_driver(&virtio_net_driver); 4106 cpuhp_remove_multi_state(CPUHP_VIRT_NET_DEAD); 4107 cpuhp_remove_multi_state(virtionet_online); 4108 } 4109 module_exit(virtio_net_driver_exit); 4110 4111 MODULE_DEVICE_TABLE(virtio, id_table); 4112 MODULE_DESCRIPTION("Virtio network driver"); 4113 MODULE_LICENSE("GPL"); 4114