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, u8 *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 = 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 iphdr *iphdr;
 194         int data_len;
 195         bool ret = false;
 196
 197         if (eth_hdr(skb)->h_proto != htons(ETH_P_IP))
 198                 return false;
 199
 200         iphdr = ip_hdr(skb);
 201
 202         if (iphdr->version == 4) {
 203                 if (iphdr->protocol == IPPROTO_TCP)
 204                         data_len = 12;
 205                 else
 206                         data_len = 8;
 207                 *hash = comp_hash(netvsc_hash_key, HASH_KEYLEN,
 208                                   (u8 *)&iphdr->saddr, data_len);
 209                 ret = true;
 210         }
 211
 212         return ret;
 213 }
 214
 215 static u16 netvsc_select_queue(struct net_device *ndev, struct sk_buff *skb,
 216                         void *accel_priv, select_queue_fallback_t fallback)
 217 {
 218         struct net_device_context *net_device_ctx = netdev_priv(ndev);
 219         struct hv_device *hdev =  net_device_ctx->device_ctx;
 220         struct netvsc_device *nvsc_dev = hv_get_drvdata(hdev);
 221         u32 hash;
 222         u16 q_idx = 0;
 223
 224         if (nvsc_dev == NULL || ndev->real_num_tx_queues <= 1)
 225                 return 0;
 226
 227         if (netvsc_set_hash(&hash, skb)) {
 228                 q_idx = nvsc_dev->send_table[hash % VRSS_SEND_TAB_SIZE] %
 229                         ndev->real_num_tx_queues;
 230                 skb_set_hash(skb, hash, PKT_HASH_TYPE_L3);
 231         }
 232
 233         return q_idx;
 234 }
 235
 236 static void netvsc_xmit_completion(void *context)
 237 {
 238         struct hv_netvsc_packet *packet = (struct hv_netvsc_packet *)context;
 239         struct sk_buff *skb = (struct sk_buff *)
 240                 (unsigned long)packet->send_completion_tid;
 241         u32 index = packet->send_buf_index;
 242
 243         kfree(packet);
 244
 245         if (skb && (index == NETVSC_INVALID_INDEX))
 246                 dev_kfree_skb_any(skb);
 247 }
 248
 249 static u32 fill_pg_buf(struct page *page, u32 offset, u32 len,
 250                         struct hv_page_buffer *pb)
 251 {
 252         int j = 0;
 253
 254         /* Deal with compund pages by ignoring unused part
 255          * of the page.
 256          */
 257         page += (offset >> PAGE_SHIFT);
 258         offset &= ~PAGE_MASK;
 259
 260         while (len > 0) {
 261                 unsigned long bytes;
 262
 263                 bytes = PAGE_SIZE - offset;
 264                 if (bytes > len)
 265                         bytes = len;
 266                 pb[j].pfn = page_to_pfn(page);
 267                 pb[j].offset = offset;
 268                 pb[j].len = bytes;
 269
 270                 offset += bytes;
 271                 len -= bytes;
 272
 273                 if (offset == PAGE_SIZE && len) {
 274                         page++;
 275                         offset = 0;
 276                         j++;
 277                 }
 278         }
 279
 280         return j + 1;
 281 }
 282
 283 static u32 init_page_array(void *hdr, u32 len, struct sk_buff *skb,
 284                            struct hv_page_buffer *pb)
 285 {
 286         u32 slots_used = 0;
 287         char *data = skb->data;
 288         int frags = skb_shinfo(skb)->nr_frags;
 289         int i;
 290
 291         /* The packet is laid out thus:
 292          * 1. hdr
 293          * 2. skb linear data
 294          * 3. skb fragment data
 295          */
 296         if (hdr != NULL)
 297                 slots_used += fill_pg_buf(virt_to_page(hdr),
 298                                         offset_in_page(hdr),
 299                                         len, &pb[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;
 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         struct rndis_per_packet_info *ppi;
 385         struct ndis_tcp_ip_checksum_info *csum_info;
 386         struct ndis_tcp_lso_info *lso_info;
 387         int  hdr_offset;
 388         u32 net_trans_info;
 389         u32 hash;
 390
 391
 392         /* We will atmost need two pages to describe the rndis
 393          * header. We can only transmit MAX_PAGE_BUFFER_COUNT number
 394          * of pages in a single packet.
 395          */
 396         num_data_pgs = netvsc_get_slots(skb) + 2;
 397         if (num_data_pgs > MAX_PAGE_BUFFER_COUNT) {
 398                 netdev_err(net, "Packet too big: %u\n", skb->len);
 399                 dev_kfree_skb(skb);
 400                 net->stats.tx_dropped++;
 401                 return NETDEV_TX_OK;
 402         }
 403
 404         /* Allocate a netvsc packet based on # of frags. */
 405         packet = kzalloc(sizeof(struct hv_netvsc_packet) +
 406                          (num_data_pgs * sizeof(struct hv_page_buffer)) +
 407                          sizeof(struct rndis_message) +
 408                          NDIS_VLAN_PPI_SIZE + NDIS_CSUM_PPI_SIZE +
 409                          NDIS_LSO_PPI_SIZE + NDIS_HASH_PPI_SIZE, GFP_ATOMIC);
 410         if (!packet) {
 411                 /* out of memory, drop packet */
 412                 netdev_err(net, "unable to allocate hv_netvsc_packet\n");
 413
 414                 dev_kfree_skb(skb);
 415                 net->stats.tx_dropped++;
 416                 return NETDEV_TX_OK;
 417         }
 418
 419         packet->vlan_tci = skb->vlan_tci;
 420
 421         packet->q_idx = skb_get_queue_mapping(skb);
 422
 423         packet->is_data_pkt = true;
 424         packet->total_data_buflen = skb->len;
 425
 426         packet->rndis_msg = (struct rndis_message *)((unsigned long)packet +
 427                                 sizeof(struct hv_netvsc_packet) +
 428                                 (num_data_pgs * sizeof(struct hv_page_buffer)));
 429
 430         /* Set the completion routine */
 431         packet->send_completion = netvsc_xmit_completion;
 432         packet->send_completion_ctx = packet;
 433         packet->send_completion_tid = (unsigned long)skb;
 434
 435         isvlan = packet->vlan_tci & VLAN_TAG_PRESENT;
 436
 437         /* Add the rndis header */
 438         rndis_msg = packet->rndis_msg;
 439         rndis_msg->ndis_msg_type = RNDIS_MSG_PACKET;
 440         rndis_msg->msg_len = packet->total_data_buflen;
 441         rndis_pkt = &rndis_msg->msg.pkt;
 442         rndis_pkt->data_offset = sizeof(struct rndis_packet);
 443         rndis_pkt->data_len = packet->total_data_buflen;
 444         rndis_pkt->per_pkt_info_offset = sizeof(struct rndis_packet);
 445
 446         rndis_msg_size = RNDIS_MESSAGE_SIZE(struct rndis_packet);
 447
 448         hash = skb_get_hash_raw(skb);
 449         if (hash != 0 && net->real_num_tx_queues > 1) {
 450                 rndis_msg_size += NDIS_HASH_PPI_SIZE;
 451                 ppi = init_ppi_data(rndis_msg, NDIS_HASH_PPI_SIZE,
 452                                     NBL_HASH_VALUE);
 453                 *(u32 *)((void *)ppi + ppi->ppi_offset) = hash;
 454         }
 455
 456         if (isvlan) {
 457                 struct ndis_pkt_8021q_info *vlan;
 458
 459                 rndis_msg_size += NDIS_VLAN_PPI_SIZE;
 460                 ppi = init_ppi_data(rndis_msg, NDIS_VLAN_PPI_SIZE,
 461                                         IEEE_8021Q_INFO);
 462                 vlan = (struct ndis_pkt_8021q_info *)((void *)ppi +
 463                                                 ppi->ppi_offset);
 464                 vlan->vlanid = packet->vlan_tci & VLAN_VID_MASK;
 465                 vlan->pri = (packet->vlan_tci & VLAN_PRIO_MASK) >>
 466                                 VLAN_PRIO_SHIFT;
 467         }
 468
 469         net_trans_info = get_net_transport_info(skb, &hdr_offset);
 470         if (net_trans_info == TRANSPORT_INFO_NOT_IP)
 471                 goto do_send;
 472
 473         /*
 474          * Setup the sendside checksum offload only if this is not a
 475          * GSO packet.
 476          */
 477         if (skb_is_gso(skb))
 478                 goto do_lso;
 479
 480         if ((skb->ip_summed == CHECKSUM_NONE) ||
 481             (skb->ip_summed == CHECKSUM_UNNECESSARY))
 482                 goto do_send;
 483
 484         rndis_msg_size += NDIS_CSUM_PPI_SIZE;
 485         ppi = init_ppi_data(rndis_msg, NDIS_CSUM_PPI_SIZE,
 486                             TCPIP_CHKSUM_PKTINFO);
 487
 488         csum_info = (struct ndis_tcp_ip_checksum_info *)((void *)ppi +
 489                         ppi->ppi_offset);
 490
 491         if (net_trans_info & (INFO_IPV4 << 16))
 492                 csum_info->transmit.is_ipv4 = 1;
 493         else
 494                 csum_info->transmit.is_ipv6 = 1;
 495
 496         if (net_trans_info & INFO_TCP) {
 497                 csum_info->transmit.tcp_checksum = 1;
 498                 csum_info->transmit.tcp_header_offset = hdr_offset;
 499         } else if (net_trans_info & INFO_UDP) {
 500                 /* UDP checksum offload is not supported on ws2008r2.
 501                  * Furthermore, on ws2012 and ws2012r2, there are some
 502                  * issues with udp checksum offload from Linux guests.
 503                  * (these are host issues).
 504                  * For now compute the checksum here.
 505                  */
 506                 struct udphdr *uh;
 507                 u16 udp_len;
 508
 509                 ret = skb_cow_head(skb, 0);
 510                 if (ret)
 511                         goto drop;
 512
 513                 uh = udp_hdr(skb);
 514                 udp_len = ntohs(uh->len);
 515                 uh->check = 0;
 516                 uh->check = csum_tcpudp_magic(ip_hdr(skb)->saddr,
 517                                               ip_hdr(skb)->daddr,
 518                                               udp_len, IPPROTO_UDP,
 519                                               csum_partial(uh, udp_len, 0));
 520                 if (uh->check == 0)
 521                         uh->check = CSUM_MANGLED_0;
 522
 523                 csum_info->transmit.udp_checksum = 0;
 524         }
 525         goto do_send;
 526
 527 do_lso:
 528         rndis_msg_size += NDIS_LSO_PPI_SIZE;
 529         ppi = init_ppi_data(rndis_msg, NDIS_LSO_PPI_SIZE,
 530                             TCP_LARGESEND_PKTINFO);
 531
 532         lso_info = (struct ndis_tcp_lso_info *)((void *)ppi +
 533                         ppi->ppi_offset);
 534
 535         lso_info->lso_v2_transmit.type = NDIS_TCP_LARGE_SEND_OFFLOAD_V2_TYPE;
 536         if (net_trans_info & (INFO_IPV4 << 16)) {
 537                 lso_info->lso_v2_transmit.ip_version =
 538                         NDIS_TCP_LARGE_SEND_OFFLOAD_IPV4;
 539                 ip_hdr(skb)->tot_len = 0;
 540                 ip_hdr(skb)->check = 0;
 541                 tcp_hdr(skb)->check =
 542                 ~csum_tcpudp_magic(ip_hdr(skb)->saddr,
 543                                    ip_hdr(skb)->daddr, 0, IPPROTO_TCP, 0);
 544         } else {
 545                 lso_info->lso_v2_transmit.ip_version =
 546                         NDIS_TCP_LARGE_SEND_OFFLOAD_IPV6;
 547                 ipv6_hdr(skb)->payload_len = 0;
 548                 tcp_hdr(skb)->check =
 549                 ~csum_ipv6_magic(&ipv6_hdr(skb)->saddr,
 550                                 &ipv6_hdr(skb)->daddr, 0, IPPROTO_TCP, 0);
 551         }
 552         lso_info->lso_v2_transmit.tcp_header_offset = hdr_offset;
 553         lso_info->lso_v2_transmit.mss = skb_shinfo(skb)->gso_size;
 554
 555 do_send:
 556         /* Start filling in the page buffers with the rndis hdr */
 557         rndis_msg->msg_len += rndis_msg_size;
 558         packet->page_buf_cnt = init_page_array(rndis_msg, rndis_msg_size,
 559                                         skb, &packet->page_buf[0]);
 560
 561         ret = netvsc_send(net_device_ctx->device_ctx, packet);
 562
 563 drop:
 564         if (ret == 0) {
 565                 net->stats.tx_bytes += skb->len;
 566                 net->stats.tx_packets++;
 567         } else {
 568                 kfree(packet);
 569                 if (ret != -EAGAIN) {
 570                         dev_kfree_skb_any(skb);
 571                         net->stats.tx_dropped++;
 572                 }
 573         }
 574
 575         return (ret == -EAGAIN) ? NETDEV_TX_BUSY : NETDEV_TX_OK;
 576 }
 577
 578 /*
 579  * netvsc_linkstatus_callback - Link up/down notification
 580  */
 581 void netvsc_linkstatus_callback(struct hv_device *device_obj,
 582                                        unsigned int status)
 583 {
 584         struct net_device *net;
 585         struct net_device_context *ndev_ctx;
 586         struct netvsc_device *net_device;
 587         struct rndis_device *rdev;
 588
 589         net_device = hv_get_drvdata(device_obj);
 590         rdev = net_device->extension;
 591
 592         rdev->link_state = status != 1;
 593
 594         net = net_device->ndev;
 595
 596         if (!net || net->reg_state != NETREG_REGISTERED)
 597                 return;
 598
 599         ndev_ctx = netdev_priv(net);
 600         if (status == 1) {
 601                 schedule_delayed_work(&ndev_ctx->dwork, 0);
 602                 schedule_delayed_work(&ndev_ctx->dwork, msecs_to_jiffies(20));
 603         } else {
 604                 schedule_delayed_work(&ndev_ctx->dwork, 0);
 605         }
 606 }
 607
 608 /*
 609  * netvsc_recv_callback -  Callback when we receive a packet from the
 610  * "wire" on the specified device.
 611  */
 612 int netvsc_recv_callback(struct hv_device *device_obj,
 613                                 struct hv_netvsc_packet *packet,
 614                                 struct ndis_tcp_ip_checksum_info *csum_info)
 615 {
 616         struct net_device *net;
 617         struct sk_buff *skb;
 618
 619         net = ((struct netvsc_device *)hv_get_drvdata(device_obj))->ndev;
 620         if (!net || net->reg_state != NETREG_REGISTERED) {
 621                 packet->status = NVSP_STAT_FAIL;
 622                 return 0;
 623         }
 624
 625         /* Allocate a skb - TODO direct I/O to pages? */
 626         skb = netdev_alloc_skb_ip_align(net, packet->total_data_buflen);
 627         if (unlikely(!skb)) {
 628                 ++net->stats.rx_dropped;
 629                 packet->status = NVSP_STAT_FAIL;
 630                 return 0;
 631         }
 632
 633         /*
 634          * Copy to skb. This copy is needed here since the memory pointed by
 635          * hv_netvsc_packet cannot be deallocated
 636          */
 637         memcpy(skb_put(skb, packet->total_data_buflen), packet->data,
 638                 packet->total_data_buflen);
 639
 640         skb->protocol = eth_type_trans(skb, net);
 641         if (csum_info) {
 642                 /* We only look at the IP checksum here.
 643                  * Should we be dropping the packet if checksum
 644                  * failed? How do we deal with other checksums - TCP/UDP?
 645                  */
 646                 if (csum_info->receive.ip_checksum_succeeded)
 647                         skb->ip_summed = CHECKSUM_UNNECESSARY;
 648                 else
 649                         skb->ip_summed = CHECKSUM_NONE;
 650         }
 651
 652         if (packet->vlan_tci & VLAN_TAG_PRESENT)
 653                 __vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q),
 654                                        packet->vlan_tci);
 655
 656         skb_record_rx_queue(skb, packet->channel->
 657                             offermsg.offer.sub_channel_index);
 658
 659         net->stats.rx_packets++;
 660         net->stats.rx_bytes += packet->total_data_buflen;
 661
 662         /*
 663          * Pass the skb back up. Network stack will deallocate the skb when it
 664          * is done.
 665          * TODO - use NAPI?
 666          */
 667         netif_rx(skb);
 668
 669         return 0;
 670 }
 671
 672 static void netvsc_get_drvinfo(struct net_device *net,
 673                                struct ethtool_drvinfo *info)
 674 {
 675         strlcpy(info->driver, KBUILD_MODNAME, sizeof(info->driver));
 676         strlcpy(info->fw_version, "N/A", sizeof(info->fw_version));
 677 }
 678
 679 static int netvsc_change_mtu(struct net_device *ndev, int mtu)
 680 {
 681         struct net_device_context *ndevctx = netdev_priv(ndev);
 682         struct hv_device *hdev =  ndevctx->device_ctx;
 683         struct netvsc_device *nvdev = hv_get_drvdata(hdev);
 684         struct netvsc_device_info device_info;
 685         int limit = ETH_DATA_LEN;
 686
 687         if (nvdev == NULL || nvdev->destroy)
 688                 return -ENODEV;
 689
 690         if (nvdev->nvsp_version >= NVSP_PROTOCOL_VERSION_2)
 691                 limit = NETVSC_MTU;
 692
 693         if (mtu < 68 || mtu > limit)
 694                 return -EINVAL;
 695
 696         nvdev->start_remove = true;
 697         cancel_work_sync(&ndevctx->work);
 698         netif_tx_disable(ndev);
 699         rndis_filter_device_remove(hdev);
 700
 701         ndev->mtu = mtu;
 702
 703         ndevctx->device_ctx = hdev;
 704         hv_set_drvdata(hdev, ndev);
 705         device_info.ring_size = ring_size;
 706         rndis_filter_device_add(hdev, &device_info);
 707         netif_tx_wake_all_queues(ndev);
 708
 709         return 0;
 710 }
 711
 712
 713 static int netvsc_set_mac_addr(struct net_device *ndev, void *p)
 714 {
 715         struct net_device_context *ndevctx = netdev_priv(ndev);
 716         struct hv_device *hdev =  ndevctx->device_ctx;
 717         struct sockaddr *addr = p;
 718         char save_adr[ETH_ALEN];
 719         unsigned char save_aatype;
 720         int err;
 721
 722         memcpy(save_adr, ndev->dev_addr, ETH_ALEN);
 723         save_aatype = ndev->addr_assign_type;
 724
 725         err = eth_mac_addr(ndev, p);
 726         if (err != 0)
 727                 return err;
 728
 729         err = rndis_filter_set_device_mac(hdev, addr->sa_data);
 730         if (err != 0) {
 731                 /* roll back to saved MAC */
 732                 memcpy(ndev->dev_addr, save_adr, ETH_ALEN);
 733                 ndev->addr_assign_type = save_aatype;
 734         }
 735
 736         return err;
 737 }
 738
 739
 740 static const struct ethtool_ops ethtool_ops = {
 741         .get_drvinfo    = netvsc_get_drvinfo,
 742         .get_link       = ethtool_op_get_link,
 743 };
 744
 745 static const struct net_device_ops device_ops = {
 746         .ndo_open =                     netvsc_open,
 747         .ndo_stop =                     netvsc_close,
 748         .ndo_start_xmit =               netvsc_start_xmit,
 749         .ndo_set_rx_mode =              netvsc_set_multicast_list,
 750         .ndo_change_mtu =               netvsc_change_mtu,
 751         .ndo_validate_addr =            eth_validate_addr,
 752         .ndo_set_mac_address =          netvsc_set_mac_addr,
 753         .ndo_select_queue =             netvsc_select_queue,
 754 };
 755
 756 /*
 757  * Send GARP packet to network peers after migrations.
 758  * After Quick Migration, the network is not immediately operational in the
 759  * current context when receiving RNDIS_STATUS_MEDIA_CONNECT event. So, add
 760  * another netif_notify_peers() into a delayed work, otherwise GARP packet
 761  * will not be sent after quick migration, and cause network disconnection.
 762  * Also, we update the carrier status here.
 763  */
 764 static void netvsc_link_change(struct work_struct *w)
 765 {
 766         struct net_device_context *ndev_ctx;
 767         struct net_device *net;
 768         struct netvsc_device *net_device;
 769         struct rndis_device *rdev;
 770         bool notify;
 771
 772         rtnl_lock();
 773
 774         ndev_ctx = container_of(w, struct net_device_context, dwork.work);
 775         net_device = hv_get_drvdata(ndev_ctx->device_ctx);
 776         rdev = net_device->extension;
 777         net = net_device->ndev;
 778
 779         if (rdev->link_state) {
 780                 netif_carrier_off(net);
 781                 notify = false;
 782         } else {
 783                 netif_carrier_on(net);
 784                 notify = true;
 785         }
 786
 787         rtnl_unlock();
 788
 789         if (notify)
 790                 netdev_notify_peers(net);
 791 }
 792
 793
 794 static int netvsc_probe(struct hv_device *dev,
 795                         const struct hv_vmbus_device_id *dev_id)
 796 {
 797         struct net_device *net = NULL;
 798         struct net_device_context *net_device_ctx;
 799         struct netvsc_device_info device_info;
 800         struct netvsc_device *nvdev;
 801         int ret;
 802
 803         net = alloc_etherdev_mq(sizeof(struct net_device_context),
 804                                 num_online_cpus());
 805         if (!net)
 806                 return -ENOMEM;
 807
 808         netif_carrier_off(net);
 809
 810         net_device_ctx = netdev_priv(net);
 811         net_device_ctx->device_ctx = dev;
 812         hv_set_drvdata(dev, net);
 813         INIT_DELAYED_WORK(&net_device_ctx->dwork, netvsc_link_change);
 814         INIT_WORK(&net_device_ctx->work, do_set_multicast);
 815
 816         net->netdev_ops = &device_ops;
 817
 818         net->hw_features = NETIF_F_RXCSUM | NETIF_F_SG | NETIF_F_IP_CSUM |
 819                                 NETIF_F_TSO;
 820         net->features = NETIF_F_HW_VLAN_CTAG_TX | NETIF_F_SG | NETIF_F_RXCSUM |
 821                         NETIF_F_IP_CSUM | NETIF_F_TSO;
 822
 823         net->ethtool_ops = &ethtool_ops;
 824         SET_NETDEV_DEV(net, &dev->device);
 825
 826         /* Notify the netvsc driver of the new device */
 827         device_info.ring_size = ring_size;
 828         ret = rndis_filter_device_add(dev, &device_info);
 829         if (ret != 0) {
 830                 netdev_err(net, "unable to add netvsc device (ret %d)\n", ret);
 831                 free_netdev(net);
 832                 hv_set_drvdata(dev, NULL);
 833                 return ret;
 834         }
 835         memcpy(net->dev_addr, device_info.mac_adr, ETH_ALEN);
 836
 837         nvdev = hv_get_drvdata(dev);
 838         netif_set_real_num_tx_queues(net, nvdev->num_chn);
 839         netif_set_real_num_rx_queues(net, nvdev->num_chn);
 840
 841         ret = register_netdev(net);
 842         if (ret != 0) {
 843                 pr_err("Unable to register netdev.\n");
 844                 rndis_filter_device_remove(dev);
 845                 free_netdev(net);
 846         } else {
 847                 schedule_delayed_work(&net_device_ctx->dwork, 0);
 848         }
 849
 850         return ret;
 851 }
 852
 853 static int netvsc_remove(struct hv_device *dev)
 854 {
 855         struct net_device *net;
 856         struct net_device_context *ndev_ctx;
 857         struct netvsc_device *net_device;
 858
 859         net_device = hv_get_drvdata(dev);
 860         net = net_device->ndev;
 861
 862         if (net == NULL) {
 863                 dev_err(&dev->device, "No net device to remove\n");
 864                 return 0;
 865         }
 866
 867         net_device->start_remove = true;
 868
 869         ndev_ctx = netdev_priv(net);
 870         cancel_delayed_work_sync(&ndev_ctx->dwork);
 871         cancel_work_sync(&ndev_ctx->work);
 872
 873         /* Stop outbound asap */
 874         netif_tx_disable(net);
 875
 876         unregister_netdev(net);
 877
 878         /*
 879          * Call to the vsc driver to let it know that the device is being
 880          * removed
 881          */
 882         rndis_filter_device_remove(dev);
 883
 884         free_netdev(net);
 885         return 0;
 886 }
 887
 888 static const struct hv_vmbus_device_id id_table[] = {
 889         /* Network guid */
 890         { HV_NIC_GUID, },
 891         { },
 892 };
 893
 894 MODULE_DEVICE_TABLE(vmbus, id_table);
 895
 896 /* The one and only one */
 897 static struct  hv_driver netvsc_drv = {
 898         .name = KBUILD_MODNAME,
 899         .id_table = id_table,
 900         .probe = netvsc_probe,
 901         .remove = netvsc_remove,
 902 };
 903
 904 static void __exit netvsc_drv_exit(void)
 905 {
 906         vmbus_driver_unregister(&netvsc_drv);
 907 }
 908
 909 static int __init netvsc_drv_init(void)
 910 {
 911         if (ring_size < RING_SIZE_MIN) {
 912                 ring_size = RING_SIZE_MIN;
 913                 pr_info("Increased ring_size to %d (min allowed)\n",
 914                         ring_size);
 915         }
 916         return vmbus_driver_register(&netvsc_drv);
 917 }
 918
 919 MODULE_LICENSE("GPL");
 920 MODULE_DESCRIPTION("Microsoft Hyper-V network driver");
 921
 922 module_init(netvsc_drv_init);
 923 module_exit(netvsc_drv_exit);