drivers/net/hyperv/netvsc_drv.c

   1 /*
   2  * Copyright (c) 2009, Microsoft Corporation.
   3  *
   4  * This program is free software; you can redistribute it and/or modify it
   5  * under the terms and conditions of the GNU General Public License,
   6  * version 2, as published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope it will be useful, but WITHOUT
   9  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  10  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  11  * more details.
  12  *
  13  * You should have received a copy of the GNU General Public License along with
  14  * this program; if not, see <http://www.gnu.org/licenses/>.
  15  *
  16  * Authors:
  17  *   Haiyang Zhang <haiyangz@microsoft.com>
  18  *   Hank Janssen  <hjanssen@microsoft.com>
  19  */
  20 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  21
  22 #include <linux/init.h>
  23 #include <linux/atomic.h>
  24 #include <linux/module.h>
  25 #include <linux/highmem.h>
  26 #include <linux/device.h>
  27 #include <linux/io.h>
  28 #include <linux/delay.h>
  29 #include <linux/netdevice.h>
  30 #include <linux/inetdevice.h>
  31 #include <linux/etherdevice.h>
  32 #include <linux/skbuff.h>
  33 #include <linux/if_vlan.h>
  34 #include <linux/in.h>
  35 #include <linux/slab.h>
  36 #include <net/arp.h>
  37 #include <net/route.h>
  38 #include <net/sock.h>
  39 #include <net/pkt_sched.h>
  40
  41 #include "hyperv_net.h"
  42
  43 struct net_device_context {
  44         /* point back to our device context */
  45         struct hv_device *device_ctx;
  46         struct delayed_work dwork;
  47         struct work_struct work;
  48 };
  49
  50 #define RING_SIZE_MIN 64
  51 static int ring_size = 128;
  52 module_param(ring_size, int, S_IRUGO);
  53 MODULE_PARM_DESC(ring_size, "Ring buffer size (# of pages)");
  54
  55 static void do_set_multicast(struct work_struct *w)
  56 {
  57         struct net_device_context *ndevctx =
  58                 container_of(w, struct net_device_context, work);
  59         struct netvsc_device *nvdev;
  60         struct rndis_device *rdev;
  61
  62         nvdev = hv_get_drvdata(ndevctx->device_ctx);
  63         if (nvdev == NULL || nvdev->ndev == NULL)
  64                 return;
  65
  66         rdev = nvdev->extension;
  67         if (rdev == NULL)
  68                 return;
  69
  70         if (nvdev->ndev->flags & IFF_PROMISC)
  71                 rndis_filter_set_packet_filter(rdev,
  72                         NDIS_PACKET_TYPE_PROMISCUOUS);
  73         else
  74                 rndis_filter_set_packet_filter(rdev,
  75                         NDIS_PACKET_TYPE_BROADCAST |
  76                         NDIS_PACKET_TYPE_ALL_MULTICAST |
  77                         NDIS_PACKET_TYPE_DIRECTED);
  78 }
  79
  80 static void netvsc_set_multicast_list(struct net_device *net)
  81 {
  82         struct net_device_context *net_device_ctx = netdev_priv(net);
  83
  84         schedule_work(&net_device_ctx->work);
  85 }
  86
  87 static int netvsc_open(struct net_device *net)
  88 {
  89         struct net_device_context *net_device_ctx = netdev_priv(net);
  90         struct hv_device *device_obj = net_device_ctx->device_ctx;
  91         struct netvsc_device *nvdev;
  92         struct rndis_device *rdev;
  93         int ret = 0;
  94
  95         netif_carrier_off(net);
  96
  97         /* Open up the device */
  98         ret = rndis_filter_open(device_obj);
  99         if (ret != 0) {
 100                 netdev_err(net, "unable to open device (ret %d).\n", ret);
 101                 return ret;
 102         }
 103
 104         netif_tx_start_all_queues(net);
 105
 106         nvdev = hv_get_drvdata(device_obj);
 107         rdev = nvdev->extension;
 108         if (!rdev->link_state)
 109                 netif_carrier_on(net);
 110
 111         return ret;
 112 }
 113
 114 static int netvsc_close(struct net_device *net)
 115 {
 116         struct net_device_context *net_device_ctx = netdev_priv(net);
 117         struct hv_device *device_obj = net_device_ctx->device_ctx;
 118         int ret;
 119
 120         netif_tx_disable(net);
 121
 122         /* Make sure netvsc_set_multicast_list doesn't re-enable filter! */
 123         cancel_work_sync(&net_device_ctx->work);
 124         ret = rndis_filter_close(device_obj);
 125         if (ret != 0)
 126                 netdev_err(net, "unable to close device (ret %d).\n", ret);
 127
 128         return ret;
 129 }
 130
 131 static void *init_ppi_data(struct rndis_message *msg, u32 ppi_size,
 132                                 int pkt_type)
 133 {
 134         struct rndis_packet *rndis_pkt;
 135         struct rndis_per_packet_info *ppi;
 136
 137         rndis_pkt = &msg->msg.pkt;
 138         rndis_pkt->data_offset += ppi_size;
 139
 140         ppi = (struct rndis_per_packet_info *)((void *)rndis_pkt +
 141                 rndis_pkt->per_pkt_info_offset + rndis_pkt->per_pkt_info_len);
 142
 143         ppi->size = ppi_size;
 144         ppi->type = pkt_type;
 145         ppi->ppi_offset = sizeof(struct rndis_per_packet_info);
 146
 147         rndis_pkt->per_pkt_info_len += ppi_size;
 148
 149         return ppi;
 150 }
 151
 152 union sub_key {
 153         u64 k;
 154         struct {
 155                 u8 pad[3];
 156                 u8 kb;
 157                 u32 ka;
 158         };
 159 };
 160
 161 /* Toeplitz hash function
 162  * data: network byte order
 163  * return: host byte order
 164  */
 165 static u32 comp_hash(u8 *key, int klen, void *data, int dlen)
 166 {
 167         union sub_key subk;
 168         int k_next = 4;
 169         u8 dt;
 170         int i, j;
 171         u32 ret = 0;
 172
 173         subk.k = 0;
 174         subk.ka = ntohl(*(u32 *)key);
 175
 176         for (i = 0; i < dlen; i++) {
 177                 subk.kb = key[k_next];
 178                 k_next = (k_next + 1) % klen;
 179                 dt = ((u8 *)data)[i];
 180                 for (j = 0; j < 8; j++) {
 181                         if (dt & 0x80)
 182                                 ret ^= subk.ka;
 183                         dt <<= 1;
 184                         subk.k <<= 1;
 185                 }
 186         }
 187
 188         return ret;
 189 }
 190
 191 static bool netvsc_set_hash(u32 *hash, struct sk_buff *skb)
 192 {
 193         struct flow_keys flow;
 194         int data_len;
 195
 196         if (!skb_flow_dissect(skb, &flow) ||
 197             !(flow.n_proto == htons(ETH_P_IP) ||
 198               flow.n_proto == htons(ETH_P_IPV6)))
 199                 return false;
 200
 201         if (flow.ip_proto == IPPROTO_TCP)
 202                 data_len = 12;
 203         else
 204                 data_len = 8;
 205
 206         *hash = comp_hash(netvsc_hash_key, HASH_KEYLEN, &flow, data_len);
 207
 208         return true;
 209 }
 210
 211 static u16 netvsc_select_queue(struct net_device *ndev, struct sk_buff *skb,
 212                         void *accel_priv, select_queue_fallback_t fallback)
 213 {
 214         struct net_device_context *net_device_ctx = netdev_priv(ndev);
 215         struct hv_device *hdev =  net_device_ctx->device_ctx;
 216         struct netvsc_device *nvsc_dev = hv_get_drvdata(hdev);
 217         u32 hash;
 218         u16 q_idx = 0;
 219
 220         if (nvsc_dev == NULL || ndev->real_num_tx_queues <= 1)
 221                 return 0;
 222
 223         if (netvsc_set_hash(&hash, skb)) {
 224                 q_idx = nvsc_dev->send_table[hash % VRSS_SEND_TAB_SIZE] %
 225                         ndev->real_num_tx_queues;
 226                 skb_set_hash(skb, hash, PKT_HASH_TYPE_L3);
 227         }
 228
 229         return q_idx;
 230 }
 231
 232 void netvsc_xmit_completion(void *context)
 233 {
 234         struct hv_netvsc_packet *packet = (struct hv_netvsc_packet *)context;
 235         struct sk_buff *skb = (struct sk_buff *)
 236                 (unsigned long)packet->send_completion_tid;
 237
 238         if (!packet->part_of_skb)
 239                 kfree(packet);
 240
 241         if (skb)
 242                 dev_kfree_skb_any(skb);
 243 }
 244
 245 static u32 fill_pg_buf(struct page *page, u32 offset, u32 len,
 246                         struct hv_page_buffer *pb)
 247 {
 248         int j = 0;
 249
 250         /* Deal with compund pages by ignoring unused part
 251          * of the page.
 252          */
 253         page += (offset >> PAGE_SHIFT);
 254         offset &= ~PAGE_MASK;
 255
 256         while (len > 0) {
 257                 unsigned long bytes;
 258
 259                 bytes = PAGE_SIZE - offset;
 260                 if (bytes > len)
 261                         bytes = len;
 262                 pb[j].pfn = page_to_pfn(page);
 263                 pb[j].offset = offset;
 264                 pb[j].len = bytes;
 265
 266                 offset += bytes;
 267                 len -= bytes;
 268
 269                 if (offset == PAGE_SIZE && len) {
 270                         page++;
 271                         offset = 0;
 272                         j++;
 273                 }
 274         }
 275
 276         return j + 1;
 277 }
 278
 279 static u32 init_page_array(void *hdr, u32 len, struct sk_buff *skb,
 280                            struct hv_netvsc_packet *packet)
 281 {
 282         struct hv_page_buffer *pb = packet->page_buf;
 283         u32 slots_used = 0;
 284         char *data = skb->data;
 285         int frags = skb_shinfo(skb)->nr_frags;
 286         int i;
 287
 288         /* The packet is laid out thus:
 289          * 1. hdr: RNDIS header and PPI
 290          * 2. skb linear data
 291          * 3. skb fragment data
 292          */
 293         if (hdr != NULL)
 294                 slots_used += fill_pg_buf(virt_to_page(hdr),
 295                                         offset_in_page(hdr),
 296                                         len, &pb[slots_used]);
 297
 298         packet->rmsg_size = len;
 299         packet->rmsg_pgcnt = slots_used;
 300
 301         slots_used += fill_pg_buf(virt_to_page(data),
 302                                 offset_in_page(data),
 303                                 skb_headlen(skb), &pb[slots_used]);
 304
 305         for (i = 0; i < frags; i++) {
 306                 skb_frag_t *frag = skb_shinfo(skb)->frags + i;
 307
 308                 slots_used += fill_pg_buf(skb_frag_page(frag),
 309                                         frag->page_offset,
 310                                         skb_frag_size(frag), &pb[slots_used]);
 311         }
 312         return slots_used;
 313 }
 314
 315 static int count_skb_frag_slots(struct sk_buff *skb)
 316 {
 317         int i, frags = skb_shinfo(skb)->nr_frags;
 318         int pages = 0;
 319
 320         for (i = 0; i < frags; i++) {
 321                 skb_frag_t *frag = skb_shinfo(skb)->frags + i;
 322                 unsigned long size = skb_frag_size(frag);
 323                 unsigned long offset = frag->page_offset;
 324
 325                 /* Skip unused frames from start of page */
 326                 offset &= ~PAGE_MASK;
 327                 pages += PFN_UP(offset + size);
 328         }
 329         return pages;
 330 }
 331
 332 static int netvsc_get_slots(struct sk_buff *skb)
 333 {
 334         char *data = skb->data;
 335         unsigned int offset = offset_in_page(data);
 336         unsigned int len = skb_headlen(skb);
 337         int slots;
 338         int frag_slots;
 339
 340         slots = DIV_ROUND_UP(offset + len, PAGE_SIZE);
 341         frag_slots = count_skb_frag_slots(skb);
 342         return slots + frag_slots;
 343 }
 344
 345 static u32 get_net_transport_info(struct sk_buff *skb, u32 *trans_off)
 346 {
 347         u32 ret_val = TRANSPORT_INFO_NOT_IP;
 348
 349         if ((eth_hdr(skb)->h_proto != htons(ETH_P_IP)) &&
 350                 (eth_hdr(skb)->h_proto != htons(ETH_P_IPV6))) {
 351                 goto not_ip;
 352         }
 353
 354         *trans_off = skb_transport_offset(skb);
 355
 356         if ((eth_hdr(skb)->h_proto == htons(ETH_P_IP))) {
 357                 struct iphdr *iphdr = ip_hdr(skb);
 358
 359                 if (iphdr->protocol == IPPROTO_TCP)
 360                         ret_val = TRANSPORT_INFO_IPV4_TCP;
 361                 else if (iphdr->protocol == IPPROTO_UDP)
 362                         ret_val = TRANSPORT_INFO_IPV4_UDP;
 363         } else {
 364                 if (ipv6_hdr(skb)->nexthdr == IPPROTO_TCP)
 365                         ret_val = TRANSPORT_INFO_IPV6_TCP;
 366                 else if (ipv6_hdr(skb)->nexthdr == IPPROTO_UDP)
 367                         ret_val = TRANSPORT_INFO_IPV6_UDP;
 368         }
 369
 370 not_ip:
 371         return ret_val;
 372 }
 373
 374 static int netvsc_start_xmit(struct sk_buff *skb, struct net_device *net)
 375 {
 376         struct net_device_context *net_device_ctx = netdev_priv(net);
 377         struct hv_netvsc_packet *packet = NULL;
 378         int ret;
 379         unsigned int num_data_pgs;
 380         struct rndis_message *rndis_msg;
 381         struct rndis_packet *rndis_pkt;
 382         u32 rndis_msg_size;
 383         bool isvlan;
 384         bool linear = false;
 385         struct rndis_per_packet_info *ppi;
 386         struct ndis_tcp_ip_checksum_info *csum_info;
 387         struct ndis_tcp_lso_info *lso_info;
 388         int  hdr_offset;
 389         u32 net_trans_info;
 390         u32 hash;
 391         u32 skb_length;
 392         u32 head_room;
 393         u32 pkt_sz;
 394         struct hv_page_buffer page_buf[MAX_PAGE_BUFFER_COUNT];
 395
 396
 397         /* We will atmost need two pages to describe the rndis
 398          * header. We can only transmit MAX_PAGE_BUFFER_COUNT number
 399          * of pages in a single packet. If skb is scattered around
 400          * more pages we try linearizing it.
 401          */
 402
 403 check_size:
 404         skb_length = skb->len;
 405         head_room = skb_headroom(skb);
 406         num_data_pgs = netvsc_get_slots(skb) + 2;
 407         if (num_data_pgs > MAX_PAGE_BUFFER_COUNT && linear) {
 408                 net_alert_ratelimited("packet too big: %u pages (%u bytes)\n",
 409                                       num_data_pgs, skb->len);
 410                 ret = -EFAULT;
 411                 goto drop;
 412         } else if (num_data_pgs > MAX_PAGE_BUFFER_COUNT) {
 413                 if (skb_linearize(skb)) {
 414                         net_alert_ratelimited("failed to linearize skb\n");
 415                         ret = -ENOMEM;
 416                         goto drop;
 417                 }
 418                 linear = true;
 419                 goto check_size;
 420         }
 421
 422         pkt_sz = sizeof(struct hv_netvsc_packet) + RNDIS_AND_PPI_SIZE;
 423
 424         if (head_room < pkt_sz) {
 425                 packet = kmalloc(pkt_sz, GFP_ATOMIC);
 426                 if (!packet) {
 427                         /* out of memory, drop packet */
 428                         netdev_err(net, "unable to alloc hv_netvsc_packet\n");
 429                         ret = -ENOMEM;
 430                         goto drop;
 431                 }
 432                 packet->part_of_skb = false;
 433         } else {
 434                 /* Use the headroom for building up the packet */
 435                 packet = (struct hv_netvsc_packet *)skb->head;
 436                 packet->part_of_skb = true;
 437         }
 438
 439         packet->status = 0;
 440         packet->xmit_more = skb->xmit_more;
 441
 442         packet->vlan_tci = skb->vlan_tci;
 443         packet->page_buf = page_buf;
 444
 445         packet->q_idx = skb_get_queue_mapping(skb);
 446
 447         packet->is_data_pkt = true;
 448         packet->total_data_buflen = skb->len;
 449
 450         packet->rndis_msg = (struct rndis_message *)((unsigned long)packet +
 451                                 sizeof(struct hv_netvsc_packet));
 452
 453         memset(packet->rndis_msg, 0, RNDIS_AND_PPI_SIZE);
 454
 455         /* Set the completion routine */
 456         packet->send_completion = netvsc_xmit_completion;
 457         packet->send_completion_ctx = packet;
 458         packet->send_completion_tid = (unsigned long)skb;
 459
 460         isvlan = packet->vlan_tci & VLAN_TAG_PRESENT;
 461
 462         /* Add the rndis header */
 463         rndis_msg = packet->rndis_msg;
 464         rndis_msg->ndis_msg_type = RNDIS_MSG_PACKET;
 465         rndis_msg->msg_len = packet->total_data_buflen;
 466         rndis_pkt = &rndis_msg->msg.pkt;
 467         rndis_pkt->data_offset = sizeof(struct rndis_packet);
 468         rndis_pkt->data_len = packet->total_data_buflen;
 469         rndis_pkt->per_pkt_info_offset = sizeof(struct rndis_packet);
 470
 471         rndis_msg_size = RNDIS_MESSAGE_SIZE(struct rndis_packet);
 472
 473         hash = skb_get_hash_raw(skb);
 474         if (hash != 0 && net->real_num_tx_queues > 1) {
 475                 rndis_msg_size += NDIS_HASH_PPI_SIZE;
 476                 ppi = init_ppi_data(rndis_msg, NDIS_HASH_PPI_SIZE,
 477                                     NBL_HASH_VALUE);
 478                 *(u32 *)((void *)ppi + ppi->ppi_offset) = hash;
 479         }
 480
 481         if (isvlan) {
 482                 struct ndis_pkt_8021q_info *vlan;
 483
 484                 rndis_msg_size += NDIS_VLAN_PPI_SIZE;
 485                 ppi = init_ppi_data(rndis_msg, NDIS_VLAN_PPI_SIZE,
 486                                         IEEE_8021Q_INFO);
 487                 vlan = (struct ndis_pkt_8021q_info *)((void *)ppi +
 488                                                 ppi->ppi_offset);
 489                 vlan->vlanid = packet->vlan_tci & VLAN_VID_MASK;
 490                 vlan->pri = (packet->vlan_tci & VLAN_PRIO_MASK) >>
 491                                 VLAN_PRIO_SHIFT;
 492         }
 493
 494         net_trans_info = get_net_transport_info(skb, &hdr_offset);
 495         if (net_trans_info == TRANSPORT_INFO_NOT_IP)
 496                 goto do_send;
 497
 498         /*
 499          * Setup the sendside checksum offload only if this is not a
 500          * GSO packet.
 501          */
 502         if (skb_is_gso(skb))
 503                 goto do_lso;
 504
 505         if ((skb->ip_summed == CHECKSUM_NONE) ||
 506             (skb->ip_summed == CHECKSUM_UNNECESSARY))
 507                 goto do_send;
 508
 509         rndis_msg_size += NDIS_CSUM_PPI_SIZE;
 510         ppi = init_ppi_data(rndis_msg, NDIS_CSUM_PPI_SIZE,
 511                             TCPIP_CHKSUM_PKTINFO);
 512
 513         csum_info = (struct ndis_tcp_ip_checksum_info *)((void *)ppi +
 514                         ppi->ppi_offset);
 515
 516         if (net_trans_info & (INFO_IPV4 << 16))
 517                 csum_info->transmit.is_ipv4 = 1;
 518         else
 519                 csum_info->transmit.is_ipv6 = 1;
 520
 521         if (net_trans_info & INFO_TCP) {
 522                 csum_info->transmit.tcp_checksum = 1;
 523                 csum_info->transmit.tcp_header_offset = hdr_offset;
 524         } else if (net_trans_info & INFO_UDP) {
 525                 /* UDP checksum offload is not supported on ws2008r2.
 526                  * Furthermore, on ws2012 and ws2012r2, there are some
 527                  * issues with udp checksum offload from Linux guests.
 528                  * (these are host issues).
 529                  * For now compute the checksum here.
 530                  */
 531                 struct udphdr *uh;
 532                 u16 udp_len;
 533
 534                 ret = skb_cow_head(skb, 0);
 535                 if (ret)
 536                         goto drop;
 537
 538                 uh = udp_hdr(skb);
 539                 udp_len = ntohs(uh->len);
 540                 uh->check = 0;
 541                 uh->check = csum_tcpudp_magic(ip_hdr(skb)->saddr,
 542                                               ip_hdr(skb)->daddr,
 543                                               udp_len, IPPROTO_UDP,
 544                                               csum_partial(uh, udp_len, 0));
 545                 if (uh->check == 0)
 546                         uh->check = CSUM_MANGLED_0;
 547
 548                 csum_info->transmit.udp_checksum = 0;
 549         }
 550         goto do_send;
 551
 552 do_lso:
 553         rndis_msg_size += NDIS_LSO_PPI_SIZE;
 554         ppi = init_ppi_data(rndis_msg, NDIS_LSO_PPI_SIZE,
 555                             TCP_LARGESEND_PKTINFO);
 556
 557         lso_info = (struct ndis_tcp_lso_info *)((void *)ppi +
 558                         ppi->ppi_offset);
 559
 560         lso_info->lso_v2_transmit.type = NDIS_TCP_LARGE_SEND_OFFLOAD_V2_TYPE;
 561         if (net_trans_info & (INFO_IPV4 << 16)) {
 562                 lso_info->lso_v2_transmit.ip_version =
 563                         NDIS_TCP_LARGE_SEND_OFFLOAD_IPV4;
 564                 ip_hdr(skb)->tot_len = 0;
 565                 ip_hdr(skb)->check = 0;
 566                 tcp_hdr(skb)->check =
 567                 ~csum_tcpudp_magic(ip_hdr(skb)->saddr,
 568                                    ip_hdr(skb)->daddr, 0, IPPROTO_TCP, 0);
 569         } else {
 570                 lso_info->lso_v2_transmit.ip_version =
 571                         NDIS_TCP_LARGE_SEND_OFFLOAD_IPV6;
 572                 ipv6_hdr(skb)->payload_len = 0;
 573                 tcp_hdr(skb)->check =
 574                 ~csum_ipv6_magic(&ipv6_hdr(skb)->saddr,
 575                                 &ipv6_hdr(skb)->daddr, 0, IPPROTO_TCP, 0);
 576         }
 577         lso_info->lso_v2_transmit.tcp_header_offset = hdr_offset;
 578         lso_info->lso_v2_transmit.mss = skb_shinfo(skb)->gso_size;
 579
 580 do_send:
 581         /* Start filling in the page buffers with the rndis hdr */
 582         rndis_msg->msg_len += rndis_msg_size;
 583         packet->total_data_buflen = rndis_msg->msg_len;
 584         packet->page_buf_cnt = init_page_array(rndis_msg, rndis_msg_size,
 585                                                skb, packet);
 586
 587         ret = netvsc_send(net_device_ctx->device_ctx, packet);
 588
 589 drop:
 590         if (ret == 0) {
 591                 net->stats.tx_bytes += skb_length;
 592                 net->stats.tx_packets++;
 593         } else {
 594                 if (packet && !packet->part_of_skb)
 595                         kfree(packet);
 596                 if (ret != -EAGAIN) {
 597                         dev_kfree_skb_any(skb);
 598                         net->stats.tx_dropped++;
 599                 }
 600         }
 601
 602         return (ret == -EAGAIN) ? NETDEV_TX_BUSY : NETDEV_TX_OK;
 603 }
 604
 605 /*
 606  * netvsc_linkstatus_callback - Link up/down notification
 607  */
 608 void netvsc_linkstatus_callback(struct hv_device *device_obj,
 609                                 struct rndis_message *resp)
 610 {
 611         struct rndis_indicate_status *indicate = &resp->msg.indicate_status;
 612         struct net_device *net;
 613         struct net_device_context *ndev_ctx;
 614         struct netvsc_device *net_device;
 615         struct rndis_device *rdev;
 616
 617         net_device = hv_get_drvdata(device_obj);
 618         rdev = net_device->extension;
 619
 620         switch (indicate->status) {
 621         case RNDIS_STATUS_MEDIA_CONNECT:
 622                 rdev->link_state = false;
 623                 break;
 624         case RNDIS_STATUS_MEDIA_DISCONNECT:
 625                 rdev->link_state = true;
 626                 break;
 627         case RNDIS_STATUS_NETWORK_CHANGE:
 628                 rdev->link_change = true;
 629                 break;
 630         default:
 631                 return;
 632         }
 633
 634         net = net_device->ndev;
 635
 636         if (!net || net->reg_state != NETREG_REGISTERED)
 637                 return;
 638
 639         ndev_ctx = netdev_priv(net);
 640         if (!rdev->link_state) {
 641                 schedule_delayed_work(&ndev_ctx->dwork, 0);
 642                 schedule_delayed_work(&ndev_ctx->dwork, msecs_to_jiffies(20));
 643         } else {
 644                 schedule_delayed_work(&ndev_ctx->dwork, 0);
 645         }
 646 }
 647
 648 /*
 649  * netvsc_recv_callback -  Callback when we receive a packet from the
 650  * "wire" on the specified device.
 651  */
 652 int netvsc_recv_callback(struct hv_device *device_obj,
 653                                 struct hv_netvsc_packet *packet,
 654                                 struct ndis_tcp_ip_checksum_info *csum_info)
 655 {
 656         struct net_device *net;
 657         struct sk_buff *skb;
 658
 659         net = ((struct netvsc_device *)hv_get_drvdata(device_obj))->ndev;
 660         if (!net || net->reg_state != NETREG_REGISTERED) {
 661                 packet->status = NVSP_STAT_FAIL;
 662                 return 0;
 663         }
 664
 665         /* Allocate a skb - TODO direct I/O to pages? */
 666         skb = netdev_alloc_skb_ip_align(net, packet->total_data_buflen);
 667         if (unlikely(!skb)) {
 668                 ++net->stats.rx_dropped;
 669                 packet->status = NVSP_STAT_FAIL;
 670                 return 0;
 671         }
 672
 673         /*
 674          * Copy to skb. This copy is needed here since the memory pointed by
 675          * hv_netvsc_packet cannot be deallocated
 676          */
 677         memcpy(skb_put(skb, packet->total_data_buflen), packet->data,
 678                 packet->total_data_buflen);
 679
 680         skb->protocol = eth_type_trans(skb, net);
 681         if (csum_info) {
 682                 /* We only look at the IP checksum here.
 683                  * Should we be dropping the packet if checksum
 684                  * failed? How do we deal with other checksums - TCP/UDP?
 685                  */
 686                 if (csum_info->receive.ip_checksum_succeeded)
 687                         skb->ip_summed = CHECKSUM_UNNECESSARY;
 688                 else
 689                         skb->ip_summed = CHECKSUM_NONE;
 690         }
 691
 692         if (packet->vlan_tci & VLAN_TAG_PRESENT)
 693                 __vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q),
 694                                        packet->vlan_tci);
 695
 696         skb_record_rx_queue(skb, packet->channel->
 697                             offermsg.offer.sub_channel_index);
 698
 699         net->stats.rx_packets++;
 700         net->stats.rx_bytes += packet->total_data_buflen;
 701
 702         /*
 703          * Pass the skb back up. Network stack will deallocate the skb when it
 704          * is done.
 705          * TODO - use NAPI?
 706          */
 707         netif_rx(skb);
 708
 709         return 0;
 710 }
 711
 712 static void netvsc_get_drvinfo(struct net_device *net,
 713                                struct ethtool_drvinfo *info)
 714 {
 715         strlcpy(info->driver, KBUILD_MODNAME, sizeof(info->driver));
 716         strlcpy(info->fw_version, "N/A", sizeof(info->fw_version));
 717 }
 718
 719 static void netvsc_get_channels(struct net_device *net,
 720                                 struct ethtool_channels *channel)
 721 {
 722         struct net_device_context *net_device_ctx = netdev_priv(net);
 723         struct hv_device *dev = net_device_ctx->device_ctx;
 724         struct netvsc_device *nvdev = hv_get_drvdata(dev);
 725
 726         if (nvdev) {
 727                 channel->max_combined   = nvdev->max_chn;
 728                 channel->combined_count = nvdev->num_chn;
 729         }
 730 }
 731
 732 static int netvsc_change_mtu(struct net_device *ndev, int mtu)
 733 {
 734         struct net_device_context *ndevctx = netdev_priv(ndev);
 735         struct hv_device *hdev =  ndevctx->device_ctx;
 736         struct netvsc_device *nvdev = hv_get_drvdata(hdev);
 737         struct netvsc_device_info device_info;
 738         int limit = ETH_DATA_LEN;
 739
 740         if (nvdev == NULL || nvdev->destroy)
 741                 return -ENODEV;
 742
 743         if (nvdev->nvsp_version >= NVSP_PROTOCOL_VERSION_2)
 744                 limit = NETVSC_MTU - ETH_HLEN;
 745
 746         /* Hyper-V hosts don't support MTU < ETH_DATA_LEN (1500) */
 747         if (mtu < ETH_DATA_LEN || mtu > limit)
 748                 return -EINVAL;
 749
 750         nvdev->start_remove = true;
 751         cancel_work_sync(&ndevctx->work);
 752         netif_tx_disable(ndev);
 753         rndis_filter_device_remove(hdev);
 754
 755         ndev->mtu = mtu;
 756
 757         ndevctx->device_ctx = hdev;
 758         hv_set_drvdata(hdev, ndev);
 759         device_info.ring_size = ring_size;
 760         rndis_filter_device_add(hdev, &device_info);
 761         netif_tx_wake_all_queues(ndev);
 762
 763         return 0;
 764 }
 765
 766
 767 static int netvsc_set_mac_addr(struct net_device *ndev, void *p)
 768 {
 769         struct net_device_context *ndevctx = netdev_priv(ndev);
 770         struct hv_device *hdev =  ndevctx->device_ctx;
 771         struct sockaddr *addr = p;
 772         char save_adr[ETH_ALEN];
 773         unsigned char save_aatype;
 774         int err;
 775
 776         memcpy(save_adr, ndev->dev_addr, ETH_ALEN);
 777         save_aatype = ndev->addr_assign_type;
 778
 779         err = eth_mac_addr(ndev, p);
 780         if (err != 0)
 781                 return err;
 782
 783         err = rndis_filter_set_device_mac(hdev, addr->sa_data);
 784         if (err != 0) {
 785                 /* roll back to saved MAC */
 786                 memcpy(ndev->dev_addr, save_adr, ETH_ALEN);
 787                 ndev->addr_assign_type = save_aatype;
 788         }
 789
 790         return err;
 791 }
 792
 793 #ifdef CONFIG_NET_POLL_CONTROLLER
 794 static void netvsc_poll_controller(struct net_device *net)
 795 {
 796         /* As netvsc_start_xmit() works synchronous we don't have to
 797          * trigger anything here.
 798          */
 799 }
 800 #endif
 801
 802 static const struct ethtool_ops ethtool_ops = {
 803         .get_drvinfo    = netvsc_get_drvinfo,
 804         .get_link       = ethtool_op_get_link,
 805         .get_channels   = netvsc_get_channels,
 806 };
 807
 808 static const struct net_device_ops device_ops = {
 809         .ndo_open =                     netvsc_open,
 810         .ndo_stop =                     netvsc_close,
 811         .ndo_start_xmit =               netvsc_start_xmit,
 812         .ndo_set_rx_mode =              netvsc_set_multicast_list,
 813         .ndo_change_mtu =               netvsc_change_mtu,
 814         .ndo_validate_addr =            eth_validate_addr,
 815         .ndo_set_mac_address =          netvsc_set_mac_addr,
 816         .ndo_select_queue =             netvsc_select_queue,
 817 #ifdef CONFIG_NET_POLL_CONTROLLER
 818         .ndo_poll_controller =          netvsc_poll_controller,
 819 #endif
 820 };
 821
 822 /*
 823  * Send GARP packet to network peers after migrations.
 824  * After Quick Migration, the network is not immediately operational in the
 825  * current context when receiving RNDIS_STATUS_MEDIA_CONNECT event. So, add
 826  * another netif_notify_peers() into a delayed work, otherwise GARP packet
 827  * will not be sent after quick migration, and cause network disconnection.
 828  * Also, we update the carrier status here.
 829  */
 830 static void netvsc_link_change(struct work_struct *w)
 831 {
 832         struct net_device_context *ndev_ctx;
 833         struct net_device *net;
 834         struct netvsc_device *net_device;
 835         struct rndis_device *rdev;
 836         bool notify, refresh = false;
 837         char *argv[] = { "/etc/init.d/network", "restart", NULL };
 838         char *envp[] = { "HOME=/", "PATH=/sbin:/usr/sbin:/bin:/usr/bin", NULL };
 839
 840         rtnl_lock();
 841
 842         ndev_ctx = container_of(w, struct net_device_context, dwork.work);
 843         net_device = hv_get_drvdata(ndev_ctx->device_ctx);
 844         rdev = net_device->extension;
 845         net = net_device->ndev;
 846
 847         if (rdev->link_state) {
 848                 netif_carrier_off(net);
 849                 notify = false;
 850         } else {
 851                 netif_carrier_on(net);
 852                 notify = true;
 853                 if (rdev->link_change) {
 854                         rdev->link_change = false;
 855                         refresh = true;
 856                 }
 857         }
 858
 859         rtnl_unlock();
 860
 861         if (refresh)
 862                 call_usermodehelper(argv[0], argv, envp, UMH_WAIT_EXEC);
 863
 864         if (notify)
 865                 netdev_notify_peers(net);
 866 }
 867
 868
 869 static int netvsc_probe(struct hv_device *dev,
 870                         const struct hv_vmbus_device_id *dev_id)
 871 {
 872         struct net_device *net = NULL;
 873         struct net_device_context *net_device_ctx;
 874         struct netvsc_device_info device_info;
 875         struct netvsc_device *nvdev;
 876         int ret;
 877         u32 max_needed_headroom;
 878
 879         net = alloc_etherdev_mq(sizeof(struct net_device_context),
 880                                 num_online_cpus());
 881         if (!net)
 882                 return -ENOMEM;
 883
 884         max_needed_headroom = sizeof(struct hv_netvsc_packet) +
 885                               RNDIS_AND_PPI_SIZE;
 886
 887         netif_carrier_off(net);
 888
 889         net_device_ctx = netdev_priv(net);
 890         net_device_ctx->device_ctx = dev;
 891         hv_set_drvdata(dev, net);
 892         INIT_DELAYED_WORK(&net_device_ctx->dwork, netvsc_link_change);
 893         INIT_WORK(&net_device_ctx->work, do_set_multicast);
 894
 895         net->netdev_ops = &device_ops;
 896
 897         net->hw_features = NETIF_F_RXCSUM | NETIF_F_SG | NETIF_F_IP_CSUM |
 898                                 NETIF_F_TSO;
 899         net->features = NETIF_F_HW_VLAN_CTAG_TX | NETIF_F_SG | NETIF_F_RXCSUM |
 900                         NETIF_F_IP_CSUM | NETIF_F_TSO;
 901
 902         net->ethtool_ops = &ethtool_ops;
 903         SET_NETDEV_DEV(net, &dev->device);
 904
 905         /*
 906          * Request additional head room in the skb.
 907          * We will use this space to build the rndis
 908          * heaser and other state we need to maintain.
 909          */
 910         net->needed_headroom = max_needed_headroom;
 911
 912         /* Notify the netvsc driver of the new device */
 913         device_info.ring_size = ring_size;
 914         ret = rndis_filter_device_add(dev, &device_info);
 915         if (ret != 0) {
 916                 netdev_err(net, "unable to add netvsc device (ret %d)\n", ret);
 917                 free_netdev(net);
 918                 hv_set_drvdata(dev, NULL);
 919                 return ret;
 920         }
 921         memcpy(net->dev_addr, device_info.mac_adr, ETH_ALEN);
 922
 923         nvdev = hv_get_drvdata(dev);
 924         netif_set_real_num_tx_queues(net, nvdev->num_chn);
 925         netif_set_real_num_rx_queues(net, nvdev->num_chn);
 926
 927         ret = register_netdev(net);
 928         if (ret != 0) {
 929                 pr_err("Unable to register netdev.\n");
 930                 rndis_filter_device_remove(dev);
 931                 free_netdev(net);
 932         } else {
 933                 schedule_delayed_work(&net_device_ctx->dwork, 0);
 934         }
 935
 936         return ret;
 937 }
 938
 939 static int netvsc_remove(struct hv_device *dev)
 940 {
 941         struct net_device *net;
 942         struct net_device_context *ndev_ctx;
 943         struct netvsc_device *net_device;
 944
 945         net_device = hv_get_drvdata(dev);
 946         net = net_device->ndev;
 947
 948         if (net == NULL) {
 949                 dev_err(&dev->device, "No net device to remove\n");
 950                 return 0;
 951         }
 952
 953         net_device->start_remove = true;
 954
 955         ndev_ctx = netdev_priv(net);
 956         cancel_delayed_work_sync(&ndev_ctx->dwork);
 957         cancel_work_sync(&ndev_ctx->work);
 958
 959         /* Stop outbound asap */
 960         netif_tx_disable(net);
 961
 962         unregister_netdev(net);
 963
 964         /*
 965          * Call to the vsc driver to let it know that the device is being
 966          * removed
 967          */
 968         rndis_filter_device_remove(dev);
 969
 970         free_netdev(net);
 971         return 0;
 972 }
 973
 974 static const struct hv_vmbus_device_id id_table[] = {
 975         /* Network guid */
 976         { HV_NIC_GUID, },
 977         { },
 978 };
 979
 980 MODULE_DEVICE_TABLE(vmbus, id_table);
 981
 982 /* The one and only one */
 983 static struct  hv_driver netvsc_drv = {
 984         .name = KBUILD_MODNAME,
 985         .id_table = id_table,
 986         .probe = netvsc_probe,
 987         .remove = netvsc_remove,
 988 };
 989
 990 static void __exit netvsc_drv_exit(void)
 991 {
 992         vmbus_driver_unregister(&netvsc_drv);
 993 }
 994
 995 static int __init netvsc_drv_init(void)
 996 {
 997         if (ring_size < RING_SIZE_MIN) {
 998                 ring_size = RING_SIZE_MIN;
 999                 pr_info("Increased ring_size to %d (min allowed)\n",
1000                         ring_size);
1001         }
1002         return vmbus_driver_register(&netvsc_drv);
1003 }
1004
1005 MODULE_LICENSE("GPL");
1006 MODULE_DESCRIPTION("Microsoft Hyper-V network driver");
1007
1008 module_init(netvsc_drv_init);
1009 module_exit(netvsc_drv_exit);