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