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 int max_num_vrss_chns = 8;
  50
  51 static const u32 default_msg = NETIF_MSG_DRV | NETIF_MSG_PROBE |
  52                                 NETIF_MSG_LINK | NETIF_MSG_IFUP |
  53                                 NETIF_MSG_IFDOWN | NETIF_MSG_RX_ERR |
  54                                 NETIF_MSG_TX_ERR;
  55
  56 static int debug = -1;
  57 module_param(debug, int, S_IRUGO);
  58 MODULE_PARM_DESC(debug, "Debug level (0=none,...,16=all)");
  59
  60 static void do_set_multicast(struct work_struct *w)
  61 {
  62         struct net_device_context *ndevctx =
  63                 container_of(w, struct net_device_context, work);
  64         struct netvsc_device *nvdev;
  65         struct rndis_device *rdev;
  66
  67         nvdev = hv_get_drvdata(ndevctx->device_ctx);
  68         if (nvdev == NULL || nvdev->ndev == NULL)
  69                 return;
  70
  71         rdev = nvdev->extension;
  72         if (rdev == NULL)
  73                 return;
  74
  75         if (nvdev->ndev->flags & IFF_PROMISC)
  76                 rndis_filter_set_packet_filter(rdev,
  77                         NDIS_PACKET_TYPE_PROMISCUOUS);
  78         else
  79                 rndis_filter_set_packet_filter(rdev,
  80                         NDIS_PACKET_TYPE_BROADCAST |
  81                         NDIS_PACKET_TYPE_ALL_MULTICAST |
  82                         NDIS_PACKET_TYPE_DIRECTED);
  83 }
  84
  85 static void netvsc_set_multicast_list(struct net_device *net)
  86 {
  87         struct net_device_context *net_device_ctx = netdev_priv(net);
  88
  89         schedule_work(&net_device_ctx->work);
  90 }
  91
  92 static int netvsc_open(struct net_device *net)
  93 {
  94         struct net_device_context *net_device_ctx = netdev_priv(net);
  95         struct hv_device *device_obj = net_device_ctx->device_ctx;
  96         struct netvsc_device *nvdev;
  97         struct rndis_device *rdev;
  98         int ret = 0;
  99
 100         netif_carrier_off(net);
 101
 102         /* Open up the device */
 103         ret = rndis_filter_open(device_obj);
 104         if (ret != 0) {
 105                 netdev_err(net, "unable to open device (ret %d).\n", ret);
 106                 return ret;
 107         }
 108
 109         netif_tx_wake_all_queues(net);
 110
 111         nvdev = hv_get_drvdata(device_obj);
 112         rdev = nvdev->extension;
 113         if (!rdev->link_state)
 114                 netif_carrier_on(net);
 115
 116         return ret;
 117 }
 118
 119 static int netvsc_close(struct net_device *net)
 120 {
 121         struct net_device_context *net_device_ctx = netdev_priv(net);
 122         struct hv_device *device_obj = net_device_ctx->device_ctx;
 123         struct netvsc_device *nvdev = hv_get_drvdata(device_obj);
 124         int ret;
 125         u32 aread, awrite, i, msec = 10, retry = 0, retry_max = 20;
 126         struct vmbus_channel *chn;
 127
 128         netif_tx_disable(net);
 129
 130         /* Make sure netvsc_set_multicast_list doesn't re-enable filter! */
 131         cancel_work_sync(&net_device_ctx->work);
 132         ret = rndis_filter_close(device_obj);
 133         if (ret != 0) {
 134                 netdev_err(net, "unable to close device (ret %d).\n", ret);
 135                 return ret;
 136         }
 137
 138         /* Ensure pending bytes in ring are read */
 139         while (true) {
 140                 aread = 0;
 141                 for (i = 0; i < nvdev->num_chn; i++) {
 142                         chn = nvdev->chn_table[i];
 143                         if (!chn)
 144                                 continue;
 145
 146                         hv_get_ringbuffer_availbytes(&chn->inbound, &aread,
 147                                                      &awrite);
 148
 149                         if (aread)
 150                                 break;
 151
 152                         hv_get_ringbuffer_availbytes(&chn->outbound, &aread,
 153                                                      &awrite);
 154
 155                         if (aread)
 156                                 break;
 157                 }
 158
 159                 retry++;
 160                 if (retry > retry_max || aread == 0)
 161                         break;
 162
 163                 msleep(msec);
 164
 165                 if (msec < 1000)
 166                         msec *= 2;
 167         }
 168
 169         if (aread) {
 170                 netdev_err(net, "Ring buffer not empty after closing rndis\n");
 171                 ret = -ETIMEDOUT;
 172         }
 173
 174         return ret;
 175 }
 176
 177 static void *init_ppi_data(struct rndis_message *msg, u32 ppi_size,
 178                                 int pkt_type)
 179 {
 180         struct rndis_packet *rndis_pkt;
 181         struct rndis_per_packet_info *ppi;
 182
 183         rndis_pkt = &msg->msg.pkt;
 184         rndis_pkt->data_offset += ppi_size;
 185
 186         ppi = (struct rndis_per_packet_info *)((void *)rndis_pkt +
 187                 rndis_pkt->per_pkt_info_offset + rndis_pkt->per_pkt_info_len);
 188
 189         ppi->size = ppi_size;
 190         ppi->type = pkt_type;
 191         ppi->ppi_offset = sizeof(struct rndis_per_packet_info);
 192
 193         rndis_pkt->per_pkt_info_len += ppi_size;
 194
 195         return ppi;
 196 }
 197
 198 union sub_key {
 199         u64 k;
 200         struct {
 201                 u8 pad[3];
 202                 u8 kb;
 203                 u32 ka;
 204         };
 205 };
 206
 207 /* Toeplitz hash function
 208  * data: network byte order
 209  * return: host byte order
 210  */
 211 static u32 comp_hash(u8 *key, int klen, void *data, int dlen)
 212 {
 213         union sub_key subk;
 214         int k_next = 4;
 215         u8 dt;
 216         int i, j;
 217         u32 ret = 0;
 218
 219         subk.k = 0;
 220         subk.ka = ntohl(*(u32 *)key);
 221
 222         for (i = 0; i < dlen; i++) {
 223                 subk.kb = key[k_next];
 224                 k_next = (k_next + 1) % klen;
 225                 dt = ((u8 *)data)[i];
 226                 for (j = 0; j < 8; j++) {
 227                         if (dt & 0x80)
 228                                 ret ^= subk.ka;
 229                         dt <<= 1;
 230                         subk.k <<= 1;
 231                 }
 232         }
 233
 234         return ret;
 235 }
 236
 237 static bool netvsc_set_hash(u32 *hash, struct sk_buff *skb)
 238 {
 239         struct flow_keys flow;
 240         int data_len;
 241
 242         if (!skb_flow_dissect_flow_keys(skb, &flow, 0) ||
 243             !(flow.basic.n_proto == htons(ETH_P_IP) ||
 244               flow.basic.n_proto == htons(ETH_P_IPV6)))
 245                 return false;
 246
 247         if (flow.basic.ip_proto == IPPROTO_TCP)
 248                 data_len = 12;
 249         else
 250                 data_len = 8;
 251
 252         *hash = comp_hash(netvsc_hash_key, HASH_KEYLEN, &flow, data_len);
 253
 254         return true;
 255 }
 256
 257 static u16 netvsc_select_queue(struct net_device *ndev, struct sk_buff *skb,
 258                         void *accel_priv, select_queue_fallback_t fallback)
 259 {
 260         struct net_device_context *net_device_ctx = netdev_priv(ndev);
 261         struct hv_device *hdev =  net_device_ctx->device_ctx;
 262         struct netvsc_device *nvsc_dev = hv_get_drvdata(hdev);
 263         u32 hash;
 264         u16 q_idx = 0;
 265
 266         if (nvsc_dev == NULL || ndev->real_num_tx_queues <= 1)
 267                 return 0;
 268
 269         if (netvsc_set_hash(&hash, skb)) {
 270                 q_idx = nvsc_dev->send_table[hash % VRSS_SEND_TAB_SIZE] %
 271                         ndev->real_num_tx_queues;
 272                 skb_set_hash(skb, hash, PKT_HASH_TYPE_L3);
 273         }
 274
 275         return q_idx;
 276 }
 277
 278 void netvsc_xmit_completion(void *context)
 279 {
 280         struct hv_netvsc_packet *packet = (struct hv_netvsc_packet *)context;
 281         struct sk_buff *skb = (struct sk_buff *)
 282                 (unsigned long)packet->send_completion_tid;
 283
 284         if (skb)
 285                 dev_kfree_skb_any(skb);
 286 }
 287
 288 static u32 fill_pg_buf(struct page *page, u32 offset, u32 len,
 289                         struct hv_page_buffer *pb)
 290 {
 291         int j = 0;
 292
 293         /* Deal with compund pages by ignoring unused part
 294          * of the page.
 295          */
 296         page += (offset >> PAGE_SHIFT);
 297         offset &= ~PAGE_MASK;
 298
 299         while (len > 0) {
 300                 unsigned long bytes;
 301
 302                 bytes = PAGE_SIZE - offset;
 303                 if (bytes > len)
 304                         bytes = len;
 305                 pb[j].pfn = page_to_pfn(page);
 306                 pb[j].offset = offset;
 307                 pb[j].len = bytes;
 308
 309                 offset += bytes;
 310                 len -= bytes;
 311
 312                 if (offset == PAGE_SIZE && len) {
 313                         page++;
 314                         offset = 0;
 315                         j++;
 316                 }
 317         }
 318
 319         return j + 1;
 320 }
 321
 322 static u32 init_page_array(void *hdr, u32 len, struct sk_buff *skb,
 323                            struct hv_netvsc_packet *packet)
 324 {
 325         struct hv_page_buffer *pb = packet->page_buf;
 326         u32 slots_used = 0;
 327         char *data = skb->data;
 328         int frags = skb_shinfo(skb)->nr_frags;
 329         int i;
 330
 331         /* The packet is laid out thus:
 332          * 1. hdr: RNDIS header and PPI
 333          * 2. skb linear data
 334          * 3. skb fragment data
 335          */
 336         if (hdr != NULL)
 337                 slots_used += fill_pg_buf(virt_to_page(hdr),
 338                                         offset_in_page(hdr),
 339                                         len, &pb[slots_used]);
 340
 341         packet->rmsg_size = len;
 342         packet->rmsg_pgcnt = slots_used;
 343
 344         slots_used += fill_pg_buf(virt_to_page(data),
 345                                 offset_in_page(data),
 346                                 skb_headlen(skb), &pb[slots_used]);
 347
 348         for (i = 0; i < frags; i++) {
 349                 skb_frag_t *frag = skb_shinfo(skb)->frags + i;
 350
 351                 slots_used += fill_pg_buf(skb_frag_page(frag),
 352                                         frag->page_offset,
 353                                         skb_frag_size(frag), &pb[slots_used]);
 354         }
 355         return slots_used;
 356 }
 357
 358 static int count_skb_frag_slots(struct sk_buff *skb)
 359 {
 360         int i, frags = skb_shinfo(skb)->nr_frags;
 361         int pages = 0;
 362
 363         for (i = 0; i < frags; i++) {
 364                 skb_frag_t *frag = skb_shinfo(skb)->frags + i;
 365                 unsigned long size = skb_frag_size(frag);
 366                 unsigned long offset = frag->page_offset;
 367
 368                 /* Skip unused frames from start of page */
 369                 offset &= ~PAGE_MASK;
 370                 pages += PFN_UP(offset + size);
 371         }
 372         return pages;
 373 }
 374
 375 static int netvsc_get_slots(struct sk_buff *skb)
 376 {
 377         char *data = skb->data;
 378         unsigned int offset = offset_in_page(data);
 379         unsigned int len = skb_headlen(skb);
 380         int slots;
 381         int frag_slots;
 382
 383         slots = DIV_ROUND_UP(offset + len, PAGE_SIZE);
 384         frag_slots = count_skb_frag_slots(skb);
 385         return slots + frag_slots;
 386 }
 387
 388 static u32 get_net_transport_info(struct sk_buff *skb, u32 *trans_off)
 389 {
 390         u32 ret_val = TRANSPORT_INFO_NOT_IP;
 391
 392         if ((eth_hdr(skb)->h_proto != htons(ETH_P_IP)) &&
 393                 (eth_hdr(skb)->h_proto != htons(ETH_P_IPV6))) {
 394                 goto not_ip;
 395         }
 396
 397         *trans_off = skb_transport_offset(skb);
 398
 399         if ((eth_hdr(skb)->h_proto == htons(ETH_P_IP))) {
 400                 struct iphdr *iphdr = ip_hdr(skb);
 401
 402                 if (iphdr->protocol == IPPROTO_TCP)
 403                         ret_val = TRANSPORT_INFO_IPV4_TCP;
 404                 else if (iphdr->protocol == IPPROTO_UDP)
 405                         ret_val = TRANSPORT_INFO_IPV4_UDP;
 406         } else {
 407                 if (ipv6_hdr(skb)->nexthdr == IPPROTO_TCP)
 408                         ret_val = TRANSPORT_INFO_IPV6_TCP;
 409                 else if (ipv6_hdr(skb)->nexthdr == IPPROTO_UDP)
 410                         ret_val = TRANSPORT_INFO_IPV6_UDP;
 411         }
 412
 413 not_ip:
 414         return ret_val;
 415 }
 416
 417 static int netvsc_start_xmit(struct sk_buff *skb, struct net_device *net)
 418 {
 419         struct net_device_context *net_device_ctx = netdev_priv(net);
 420         struct hv_netvsc_packet *packet = NULL;
 421         int ret;
 422         unsigned int num_data_pgs;
 423         struct rndis_message *rndis_msg;
 424         struct rndis_packet *rndis_pkt;
 425         u32 rndis_msg_size;
 426         bool isvlan;
 427         bool linear = false;
 428         struct rndis_per_packet_info *ppi;
 429         struct ndis_tcp_ip_checksum_info *csum_info;
 430         struct ndis_tcp_lso_info *lso_info;
 431         int  hdr_offset;
 432         u32 net_trans_info;
 433         u32 hash;
 434         u32 skb_length;
 435         u32 pkt_sz;
 436         struct hv_page_buffer page_buf[MAX_PAGE_BUFFER_COUNT];
 437         struct netvsc_stats *tx_stats = this_cpu_ptr(net_device_ctx->tx_stats);
 438
 439         /* We will atmost need two pages to describe the rndis
 440          * header. We can only transmit MAX_PAGE_BUFFER_COUNT number
 441          * of pages in a single packet. If skb is scattered around
 442          * more pages we try linearizing it.
 443          */
 444
 445 check_size:
 446         skb_length = skb->len;
 447         num_data_pgs = netvsc_get_slots(skb) + 2;
 448         if (num_data_pgs > MAX_PAGE_BUFFER_COUNT && linear) {
 449                 net_alert_ratelimited("packet too big: %u pages (%u bytes)\n",
 450                                       num_data_pgs, skb->len);
 451                 ret = -EFAULT;
 452                 goto drop;
 453         } else if (num_data_pgs > MAX_PAGE_BUFFER_COUNT) {
 454                 if (skb_linearize(skb)) {
 455                         net_alert_ratelimited("failed to linearize skb\n");
 456                         ret = -ENOMEM;
 457                         goto drop;
 458                 }
 459                 linear = true;
 460                 goto check_size;
 461         }
 462
 463         pkt_sz = sizeof(struct hv_netvsc_packet) + RNDIS_AND_PPI_SIZE;
 464
 465         ret = skb_cow_head(skb, pkt_sz);
 466         if (ret) {
 467                 netdev_err(net, "unable to alloc hv_netvsc_packet\n");
 468                 ret = -ENOMEM;
 469                 goto drop;
 470         }
 471         /* Use the headroom for building up the packet */
 472         packet = (struct hv_netvsc_packet *)skb->head;
 473
 474         packet->status = 0;
 475         packet->xmit_more = skb->xmit_more;
 476
 477         packet->vlan_tci = skb->vlan_tci;
 478         packet->page_buf = page_buf;
 479
 480         packet->q_idx = skb_get_queue_mapping(skb);
 481
 482         packet->is_data_pkt = true;
 483         packet->total_data_buflen = skb->len;
 484
 485         packet->rndis_msg = (struct rndis_message *)((unsigned long)packet +
 486                                 sizeof(struct hv_netvsc_packet));
 487
 488         memset(packet->rndis_msg, 0, RNDIS_AND_PPI_SIZE);
 489
 490         /* Set the completion routine */
 491         packet->send_completion = netvsc_xmit_completion;
 492         packet->send_completion_ctx = packet;
 493         packet->send_completion_tid = (unsigned long)skb;
 494
 495         isvlan = packet->vlan_tci & VLAN_TAG_PRESENT;
 496
 497         /* Add the rndis header */
 498         rndis_msg = packet->rndis_msg;
 499         rndis_msg->ndis_msg_type = RNDIS_MSG_PACKET;
 500         rndis_msg->msg_len = packet->total_data_buflen;
 501         rndis_pkt = &rndis_msg->msg.pkt;
 502         rndis_pkt->data_offset = sizeof(struct rndis_packet);
 503         rndis_pkt->data_len = packet->total_data_buflen;
 504         rndis_pkt->per_pkt_info_offset = sizeof(struct rndis_packet);
 505
 506         rndis_msg_size = RNDIS_MESSAGE_SIZE(struct rndis_packet);
 507
 508         hash = skb_get_hash_raw(skb);
 509         if (hash != 0 && net->real_num_tx_queues > 1) {
 510                 rndis_msg_size += NDIS_HASH_PPI_SIZE;
 511                 ppi = init_ppi_data(rndis_msg, NDIS_HASH_PPI_SIZE,
 512                                     NBL_HASH_VALUE);
 513                 *(u32 *)((void *)ppi + ppi->ppi_offset) = hash;
 514         }
 515
 516         if (isvlan) {
 517                 struct ndis_pkt_8021q_info *vlan;
 518
 519                 rndis_msg_size += NDIS_VLAN_PPI_SIZE;
 520                 ppi = init_ppi_data(rndis_msg, NDIS_VLAN_PPI_SIZE,
 521                                         IEEE_8021Q_INFO);
 522                 vlan = (struct ndis_pkt_8021q_info *)((void *)ppi +
 523                                                 ppi->ppi_offset);
 524                 vlan->vlanid = packet->vlan_tci & VLAN_VID_MASK;
 525                 vlan->pri = (packet->vlan_tci & VLAN_PRIO_MASK) >>
 526                                 VLAN_PRIO_SHIFT;
 527         }
 528
 529         net_trans_info = get_net_transport_info(skb, &hdr_offset);
 530         if (net_trans_info == TRANSPORT_INFO_NOT_IP)
 531                 goto do_send;
 532
 533         /*
 534          * Setup the sendside checksum offload only if this is not a
 535          * GSO packet.
 536          */
 537         if (skb_is_gso(skb))
 538                 goto do_lso;
 539
 540         if ((skb->ip_summed == CHECKSUM_NONE) ||
 541             (skb->ip_summed == CHECKSUM_UNNECESSARY))
 542                 goto do_send;
 543
 544         rndis_msg_size += NDIS_CSUM_PPI_SIZE;
 545         ppi = init_ppi_data(rndis_msg, NDIS_CSUM_PPI_SIZE,
 546                             TCPIP_CHKSUM_PKTINFO);
 547
 548         csum_info = (struct ndis_tcp_ip_checksum_info *)((void *)ppi +
 549                         ppi->ppi_offset);
 550
 551         if (net_trans_info & (INFO_IPV4 << 16))
 552                 csum_info->transmit.is_ipv4 = 1;
 553         else
 554                 csum_info->transmit.is_ipv6 = 1;
 555
 556         if (net_trans_info & INFO_TCP) {
 557                 csum_info->transmit.tcp_checksum = 1;
 558                 csum_info->transmit.tcp_header_offset = hdr_offset;
 559         } else if (net_trans_info & INFO_UDP) {
 560                 /* UDP checksum offload is not supported on ws2008r2.
 561                  * Furthermore, on ws2012 and ws2012r2, there are some
 562                  * issues with udp checksum offload from Linux guests.
 563                  * (these are host issues).
 564                  * For now compute the checksum here.
 565                  */
 566                 struct udphdr *uh;
 567                 u16 udp_len;
 568
 569                 ret = skb_cow_head(skb, 0);
 570                 if (ret)
 571                         goto drop;
 572
 573                 uh = udp_hdr(skb);
 574                 udp_len = ntohs(uh->len);
 575                 uh->check = 0;
 576                 uh->check = csum_tcpudp_magic(ip_hdr(skb)->saddr,
 577                                               ip_hdr(skb)->daddr,
 578                                               udp_len, IPPROTO_UDP,
 579                                               csum_partial(uh, udp_len, 0));
 580                 if (uh->check == 0)
 581                         uh->check = CSUM_MANGLED_0;
 582
 583                 csum_info->transmit.udp_checksum = 0;
 584         }
 585         goto do_send;
 586
 587 do_lso:
 588         rndis_msg_size += NDIS_LSO_PPI_SIZE;
 589         ppi = init_ppi_data(rndis_msg, NDIS_LSO_PPI_SIZE,
 590                             TCP_LARGESEND_PKTINFO);
 591
 592         lso_info = (struct ndis_tcp_lso_info *)((void *)ppi +
 593                         ppi->ppi_offset);
 594
 595         lso_info->lso_v2_transmit.type = NDIS_TCP_LARGE_SEND_OFFLOAD_V2_TYPE;
 596         if (net_trans_info & (INFO_IPV4 << 16)) {
 597                 lso_info->lso_v2_transmit.ip_version =
 598                         NDIS_TCP_LARGE_SEND_OFFLOAD_IPV4;
 599                 ip_hdr(skb)->tot_len = 0;
 600                 ip_hdr(skb)->check = 0;
 601                 tcp_hdr(skb)->check =
 602                 ~csum_tcpudp_magic(ip_hdr(skb)->saddr,
 603                                    ip_hdr(skb)->daddr, 0, IPPROTO_TCP, 0);
 604         } else {
 605                 lso_info->lso_v2_transmit.ip_version =
 606                         NDIS_TCP_LARGE_SEND_OFFLOAD_IPV6;
 607                 ipv6_hdr(skb)->payload_len = 0;
 608                 tcp_hdr(skb)->check =
 609                 ~csum_ipv6_magic(&ipv6_hdr(skb)->saddr,
 610                                 &ipv6_hdr(skb)->daddr, 0, IPPROTO_TCP, 0);
 611         }
 612         lso_info->lso_v2_transmit.tcp_header_offset = hdr_offset;
 613         lso_info->lso_v2_transmit.mss = skb_shinfo(skb)->gso_size;
 614
 615 do_send:
 616         /* Start filling in the page buffers with the rndis hdr */
 617         rndis_msg->msg_len += rndis_msg_size;
 618         packet->total_data_buflen = rndis_msg->msg_len;
 619         packet->page_buf_cnt = init_page_array(rndis_msg, rndis_msg_size,
 620                                                skb, packet);
 621
 622         ret = netvsc_send(net_device_ctx->device_ctx, packet);
 623
 624 drop:
 625         if (ret == 0) {
 626                 u64_stats_update_begin(&tx_stats->syncp);
 627                 tx_stats->packets++;
 628                 tx_stats->bytes += skb_length;
 629                 u64_stats_update_end(&tx_stats->syncp);
 630         } else {
 631                 if (ret != -EAGAIN) {
 632                         dev_kfree_skb_any(skb);
 633                         net->stats.tx_dropped++;
 634                 }
 635         }
 636
 637         return (ret == -EAGAIN) ? NETDEV_TX_BUSY : NETDEV_TX_OK;
 638 }
 639
 640 /*
 641  * netvsc_linkstatus_callback - Link up/down notification
 642  */
 643 void netvsc_linkstatus_callback(struct hv_device *device_obj,
 644                                 struct rndis_message *resp)
 645 {
 646         struct rndis_indicate_status *indicate = &resp->msg.indicate_status;
 647         struct net_device *net;
 648         struct net_device_context *ndev_ctx;
 649         struct netvsc_device *net_device;
 650         struct rndis_device *rdev;
 651
 652         net_device = hv_get_drvdata(device_obj);
 653         rdev = net_device->extension;
 654
 655         switch (indicate->status) {
 656         case RNDIS_STATUS_MEDIA_CONNECT:
 657                 rdev->link_state = false;
 658                 break;
 659         case RNDIS_STATUS_MEDIA_DISCONNECT:
 660                 rdev->link_state = true;
 661                 break;
 662         case RNDIS_STATUS_NETWORK_CHANGE:
 663                 rdev->link_change = true;
 664                 break;
 665         default:
 666                 return;
 667         }
 668
 669         net = net_device->ndev;
 670
 671         if (!net || net->reg_state != NETREG_REGISTERED)
 672                 return;
 673
 674         ndev_ctx = netdev_priv(net);
 675         if (!rdev->link_state) {
 676                 schedule_delayed_work(&ndev_ctx->dwork, 0);
 677                 schedule_delayed_work(&ndev_ctx->dwork, msecs_to_jiffies(20));
 678         } else {
 679                 schedule_delayed_work(&ndev_ctx->dwork, 0);
 680         }
 681 }
 682
 683 /*
 684  * netvsc_recv_callback -  Callback when we receive a packet from the
 685  * "wire" on the specified device.
 686  */
 687 int netvsc_recv_callback(struct hv_device *device_obj,
 688                                 struct hv_netvsc_packet *packet,
 689                                 struct ndis_tcp_ip_checksum_info *csum_info)
 690 {
 691         struct net_device *net;
 692         struct net_device_context *net_device_ctx;
 693         struct sk_buff *skb;
 694         struct netvsc_stats *rx_stats;
 695
 696         net = ((struct netvsc_device *)hv_get_drvdata(device_obj))->ndev;
 697         if (!net || net->reg_state != NETREG_REGISTERED) {
 698                 packet->status = NVSP_STAT_FAIL;
 699                 return 0;
 700         }
 701         net_device_ctx = netdev_priv(net);
 702         rx_stats = this_cpu_ptr(net_device_ctx->rx_stats);
 703
 704         /* Allocate a skb - TODO direct I/O to pages? */
 705         skb = netdev_alloc_skb_ip_align(net, packet->total_data_buflen);
 706         if (unlikely(!skb)) {
 707                 ++net->stats.rx_dropped;
 708                 packet->status = NVSP_STAT_FAIL;
 709                 return 0;
 710         }
 711
 712         /*
 713          * Copy to skb. This copy is needed here since the memory pointed by
 714          * hv_netvsc_packet cannot be deallocated
 715          */
 716         memcpy(skb_put(skb, packet->total_data_buflen), packet->data,
 717                 packet->total_data_buflen);
 718
 719         skb->protocol = eth_type_trans(skb, net);
 720         if (csum_info) {
 721                 /* We only look at the IP checksum here.
 722                  * Should we be dropping the packet if checksum
 723                  * failed? How do we deal with other checksums - TCP/UDP?
 724                  */
 725                 if (csum_info->receive.ip_checksum_succeeded)
 726                         skb->ip_summed = CHECKSUM_UNNECESSARY;
 727                 else
 728                         skb->ip_summed = CHECKSUM_NONE;
 729         }
 730
 731         if (packet->vlan_tci & VLAN_TAG_PRESENT)
 732                 __vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q),
 733                                        packet->vlan_tci);
 734
 735         skb_record_rx_queue(skb, packet->channel->
 736                             offermsg.offer.sub_channel_index);
 737
 738         u64_stats_update_begin(&rx_stats->syncp);
 739         rx_stats->packets++;
 740         rx_stats->bytes += packet->total_data_buflen;
 741         u64_stats_update_end(&rx_stats->syncp);
 742
 743         /*
 744          * Pass the skb back up. Network stack will deallocate the skb when it
 745          * is done.
 746          * TODO - use NAPI?
 747          */
 748         netif_rx(skb);
 749
 750         return 0;
 751 }
 752
 753 static void netvsc_get_drvinfo(struct net_device *net,
 754                                struct ethtool_drvinfo *info)
 755 {
 756         strlcpy(info->driver, KBUILD_MODNAME, sizeof(info->driver));
 757         strlcpy(info->fw_version, "N/A", sizeof(info->fw_version));
 758 }
 759
 760 static void netvsc_get_channels(struct net_device *net,
 761                                 struct ethtool_channels *channel)
 762 {
 763         struct net_device_context *net_device_ctx = netdev_priv(net);
 764         struct hv_device *dev = net_device_ctx->device_ctx;
 765         struct netvsc_device *nvdev = hv_get_drvdata(dev);
 766
 767         if (nvdev) {
 768                 channel->max_combined   = nvdev->max_chn;
 769                 channel->combined_count = nvdev->num_chn;
 770         }
 771 }
 772
 773 static int netvsc_set_channels(struct net_device *net,
 774                                struct ethtool_channels *channels)
 775 {
 776         struct net_device_context *net_device_ctx = netdev_priv(net);
 777         struct hv_device *dev = net_device_ctx->device_ctx;
 778         struct netvsc_device *nvdev = hv_get_drvdata(dev);
 779         struct netvsc_device_info device_info;
 780         u32 num_chn;
 781         u32 max_chn;
 782         int ret = 0;
 783         bool recovering = false;
 784
 785         if (!nvdev || nvdev->destroy)
 786                 return -ENODEV;
 787
 788         num_chn = nvdev->num_chn;
 789         max_chn = min_t(u32, nvdev->max_chn, num_online_cpus());
 790
 791         if (nvdev->nvsp_version < NVSP_PROTOCOL_VERSION_5) {
 792                 pr_info("vRSS unsupported before NVSP Version 5\n");
 793                 return -EINVAL;
 794         }
 795
 796         /* We do not support rx, tx, or other */
 797         if (!channels ||
 798             channels->rx_count ||
 799             channels->tx_count ||
 800             channels->other_count ||
 801             (channels->combined_count < 1))
 802                 return -EINVAL;
 803
 804         if (channels->combined_count > max_chn) {
 805                 pr_info("combined channels too high, using %d\n", max_chn);
 806                 channels->combined_count = max_chn;
 807         }
 808
 809         ret = netvsc_close(net);
 810         if (ret)
 811                 goto out;
 812
 813  do_set:
 814         nvdev->start_remove = true;
 815         rndis_filter_device_remove(dev);
 816
 817         nvdev->num_chn = channels->combined_count;
 818
 819         net_device_ctx->device_ctx = dev;
 820         hv_set_drvdata(dev, net);
 821
 822         memset(&device_info, 0, sizeof(device_info));
 823         device_info.num_chn = nvdev->num_chn; /* passed to RNDIS */
 824         device_info.ring_size = ring_size;
 825         device_info.max_num_vrss_chns = max_num_vrss_chns;
 826
 827         ret = rndis_filter_device_add(dev, &device_info);
 828         if (ret) {
 829                 if (recovering) {
 830                         netdev_err(net, "unable to add netvsc device (ret %d)\n", ret);
 831                         return ret;
 832                 }
 833                 goto recover;
 834         }
 835
 836         nvdev = hv_get_drvdata(dev);
 837
 838         ret = netif_set_real_num_tx_queues(net, nvdev->num_chn);
 839         if (ret) {
 840                 if (recovering) {
 841                         netdev_err(net, "could not set tx queue count (ret %d)\n", ret);
 842                         return ret;
 843                 }
 844                 goto recover;
 845         }
 846
 847         ret = netif_set_real_num_rx_queues(net, nvdev->num_chn);
 848         if (ret) {
 849                 if (recovering) {
 850                         netdev_err(net, "could not set rx queue count (ret %d)\n", ret);
 851                         return ret;
 852                 }
 853                 goto recover;
 854         }
 855
 856  out:
 857         netvsc_open(net);
 858
 859         return ret;
 860
 861  recover:
 862         /* If the above failed, we attempt to recover through the same
 863          * process but with the original number of channels.
 864          */
 865         netdev_err(net, "could not set channels, recovering\n");
 866         recovering = true;
 867         channels->combined_count = num_chn;
 868         goto do_set;
 869 }
 870
 871 static int netvsc_change_mtu(struct net_device *ndev, int mtu)
 872 {
 873         struct net_device_context *ndevctx = netdev_priv(ndev);
 874         struct hv_device *hdev =  ndevctx->device_ctx;
 875         struct netvsc_device *nvdev = hv_get_drvdata(hdev);
 876         struct netvsc_device_info device_info;
 877         int limit = ETH_DATA_LEN;
 878         int ret = 0;
 879
 880         if (nvdev == NULL || nvdev->destroy)
 881                 return -ENODEV;
 882
 883         if (nvdev->nvsp_version >= NVSP_PROTOCOL_VERSION_2)
 884                 limit = NETVSC_MTU - ETH_HLEN;
 885
 886         if (mtu < NETVSC_MTU_MIN || mtu > limit)
 887                 return -EINVAL;
 888
 889         ret = netvsc_close(ndev);
 890         if (ret)
 891                 goto out;
 892
 893         nvdev->start_remove = true;
 894         rndis_filter_device_remove(hdev);
 895
 896         ndev->mtu = mtu;
 897
 898         ndevctx->device_ctx = hdev;
 899         hv_set_drvdata(hdev, ndev);
 900
 901         memset(&device_info, 0, sizeof(device_info));
 902         device_info.ring_size = ring_size;
 903         device_info.num_chn = nvdev->num_chn;
 904         device_info.max_num_vrss_chns = max_num_vrss_chns;
 905         rndis_filter_device_add(hdev, &device_info);
 906
 907 out:
 908         netvsc_open(ndev);
 909
 910         return ret;
 911 }
 912
 913 static struct rtnl_link_stats64 *netvsc_get_stats64(struct net_device *net,
 914                                                     struct rtnl_link_stats64 *t)
 915 {
 916         struct net_device_context *ndev_ctx = netdev_priv(net);
 917         int cpu;
 918
 919         for_each_possible_cpu(cpu) {
 920                 struct netvsc_stats *tx_stats = per_cpu_ptr(ndev_ctx->tx_stats,
 921                                                             cpu);
 922                 struct netvsc_stats *rx_stats = per_cpu_ptr(ndev_ctx->rx_stats,
 923                                                             cpu);
 924                 u64 tx_packets, tx_bytes, rx_packets, rx_bytes;
 925                 unsigned int start;
 926
 927                 do {
 928                         start = u64_stats_fetch_begin_irq(&tx_stats->syncp);
 929                         tx_packets = tx_stats->packets;
 930                         tx_bytes = tx_stats->bytes;
 931                 } while (u64_stats_fetch_retry_irq(&tx_stats->syncp, start));
 932
 933                 do {
 934                         start = u64_stats_fetch_begin_irq(&rx_stats->syncp);
 935                         rx_packets = rx_stats->packets;
 936                         rx_bytes = rx_stats->bytes;
 937                 } while (u64_stats_fetch_retry_irq(&rx_stats->syncp, start));
 938
 939                 t->tx_bytes     += tx_bytes;
 940                 t->tx_packets   += tx_packets;
 941                 t->rx_bytes     += rx_bytes;
 942                 t->rx_packets   += rx_packets;
 943         }
 944
 945         t->tx_dropped   = net->stats.tx_dropped;
 946         t->tx_errors    = net->stats.tx_dropped;
 947
 948         t->rx_dropped   = net->stats.rx_dropped;
 949         t->rx_errors    = net->stats.rx_errors;
 950
 951         return t;
 952 }
 953
 954 static int netvsc_set_mac_addr(struct net_device *ndev, void *p)
 955 {
 956         struct net_device_context *ndevctx = netdev_priv(ndev);
 957         struct hv_device *hdev =  ndevctx->device_ctx;
 958         struct sockaddr *addr = p;
 959         char save_adr[ETH_ALEN];
 960         unsigned char save_aatype;
 961         int err;
 962
 963         memcpy(save_adr, ndev->dev_addr, ETH_ALEN);
 964         save_aatype = ndev->addr_assign_type;
 965
 966         err = eth_mac_addr(ndev, p);
 967         if (err != 0)
 968                 return err;
 969
 970         err = rndis_filter_set_device_mac(hdev, addr->sa_data);
 971         if (err != 0) {
 972                 /* roll back to saved MAC */
 973                 memcpy(ndev->dev_addr, save_adr, ETH_ALEN);
 974                 ndev->addr_assign_type = save_aatype;
 975         }
 976
 977         return err;
 978 }
 979
 980 #ifdef CONFIG_NET_POLL_CONTROLLER
 981 static void netvsc_poll_controller(struct net_device *net)
 982 {
 983         /* As netvsc_start_xmit() works synchronous we don't have to
 984          * trigger anything here.
 985          */
 986 }
 987 #endif
 988
 989 static const struct ethtool_ops ethtool_ops = {
 990         .get_drvinfo    = netvsc_get_drvinfo,
 991         .get_link       = ethtool_op_get_link,
 992         .get_channels   = netvsc_get_channels,
 993         .set_channels   = netvsc_set_channels,
 994 };
 995
 996 static const struct net_device_ops device_ops = {
 997         .ndo_open =                     netvsc_open,
 998         .ndo_stop =                     netvsc_close,
 999         .ndo_start_xmit =               netvsc_start_xmit,
1000         .ndo_set_rx_mode =              netvsc_set_multicast_list,
1001         .ndo_change_mtu =               netvsc_change_mtu,
1002         .ndo_validate_addr =            eth_validate_addr,
1003         .ndo_set_mac_address =          netvsc_set_mac_addr,
1004         .ndo_select_queue =             netvsc_select_queue,
1005         .ndo_get_stats64 =              netvsc_get_stats64,
1006 #ifdef CONFIG_NET_POLL_CONTROLLER
1007         .ndo_poll_controller =          netvsc_poll_controller,
1008 #endif
1009 };
1010
1011 /*
1012  * Send GARP packet to network peers after migrations.
1013  * After Quick Migration, the network is not immediately operational in the
1014  * current context when receiving RNDIS_STATUS_MEDIA_CONNECT event. So, add
1015  * another netif_notify_peers() into a delayed work, otherwise GARP packet
1016  * will not be sent after quick migration, and cause network disconnection.
1017  * Also, we update the carrier status here.
1018  */
1019 static void netvsc_link_change(struct work_struct *w)
1020 {
1021         struct net_device_context *ndev_ctx;
1022         struct net_device *net;
1023         struct netvsc_device *net_device;
1024         struct rndis_device *rdev;
1025         bool notify, refresh = false;
1026         char *argv[] = { "/etc/init.d/network", "restart", NULL };
1027         char *envp[] = { "HOME=/", "PATH=/sbin:/usr/sbin:/bin:/usr/bin", NULL };
1028
1029         rtnl_lock();
1030
1031         ndev_ctx = container_of(w, struct net_device_context, dwork.work);
1032         net_device = hv_get_drvdata(ndev_ctx->device_ctx);
1033         rdev = net_device->extension;
1034         net = net_device->ndev;
1035
1036         if (rdev->link_state) {
1037                 netif_carrier_off(net);
1038                 notify = false;
1039         } else {
1040                 netif_carrier_on(net);
1041                 notify = true;
1042                 if (rdev->link_change) {
1043                         rdev->link_change = false;
1044                         refresh = true;
1045                 }
1046         }
1047
1048         rtnl_unlock();
1049
1050         if (refresh)
1051                 call_usermodehelper(argv[0], argv, envp, UMH_WAIT_EXEC);
1052
1053         if (notify)
1054                 netdev_notify_peers(net);
1055 }
1056
1057 static void netvsc_free_netdev(struct net_device *netdev)
1058 {
1059         struct net_device_context *net_device_ctx = netdev_priv(netdev);
1060
1061         free_percpu(net_device_ctx->tx_stats);
1062         free_percpu(net_device_ctx->rx_stats);
1063         free_netdev(netdev);
1064 }
1065
1066 static int netvsc_probe(struct hv_device *dev,
1067                         const struct hv_vmbus_device_id *dev_id)
1068 {
1069         struct net_device *net = NULL;
1070         struct net_device_context *net_device_ctx;
1071         struct netvsc_device_info device_info;
1072         struct netvsc_device *nvdev;
1073         int ret;
1074         u32 max_needed_headroom;
1075
1076         net = alloc_etherdev_mq(sizeof(struct net_device_context),
1077                                 num_online_cpus());
1078         if (!net)
1079                 return -ENOMEM;
1080
1081         max_needed_headroom = sizeof(struct hv_netvsc_packet) +
1082                               RNDIS_AND_PPI_SIZE;
1083
1084         netif_carrier_off(net);
1085
1086         net_device_ctx = netdev_priv(net);
1087         net_device_ctx->device_ctx = dev;
1088         net_device_ctx->msg_enable = netif_msg_init(debug, default_msg);
1089         if (netif_msg_probe(net_device_ctx))
1090                 netdev_dbg(net, "netvsc msg_enable: %d\n",
1091                            net_device_ctx->msg_enable);
1092
1093         net_device_ctx->tx_stats = netdev_alloc_pcpu_stats(struct netvsc_stats);
1094         if (!net_device_ctx->tx_stats) {
1095                 free_netdev(net);
1096                 return -ENOMEM;
1097         }
1098         net_device_ctx->rx_stats = netdev_alloc_pcpu_stats(struct netvsc_stats);
1099         if (!net_device_ctx->rx_stats) {
1100                 free_percpu(net_device_ctx->tx_stats);
1101                 free_netdev(net);
1102                 return -ENOMEM;
1103         }
1104
1105         hv_set_drvdata(dev, net);
1106         INIT_DELAYED_WORK(&net_device_ctx->dwork, netvsc_link_change);
1107         INIT_WORK(&net_device_ctx->work, do_set_multicast);
1108
1109         net->netdev_ops = &device_ops;
1110
1111         net->hw_features = NETIF_F_RXCSUM | NETIF_F_SG | NETIF_F_IP_CSUM |
1112                                 NETIF_F_TSO;
1113         net->features = NETIF_F_HW_VLAN_CTAG_TX | NETIF_F_SG | NETIF_F_RXCSUM |
1114                         NETIF_F_IP_CSUM | NETIF_F_TSO;
1115
1116         net->ethtool_ops = &ethtool_ops;
1117         SET_NETDEV_DEV(net, &dev->device);
1118
1119         /*
1120          * Request additional head room in the skb.
1121          * We will use this space to build the rndis
1122          * heaser and other state we need to maintain.
1123          */
1124         net->needed_headroom = max_needed_headroom;
1125
1126         /* Notify the netvsc driver of the new device */
1127         memset(&device_info, 0, sizeof(device_info));
1128         device_info.ring_size = ring_size;
1129         device_info.max_num_vrss_chns = max_num_vrss_chns;
1130         ret = rndis_filter_device_add(dev, &device_info);
1131         if (ret != 0) {
1132                 netdev_err(net, "unable to add netvsc device (ret %d)\n", ret);
1133                 netvsc_free_netdev(net);
1134                 hv_set_drvdata(dev, NULL);
1135                 return ret;
1136         }
1137         memcpy(net->dev_addr, device_info.mac_adr, ETH_ALEN);
1138
1139         nvdev = hv_get_drvdata(dev);
1140         netif_set_real_num_tx_queues(net, nvdev->num_chn);
1141         netif_set_real_num_rx_queues(net, nvdev->num_chn);
1142
1143         ret = register_netdev(net);
1144         if (ret != 0) {
1145                 pr_err("Unable to register netdev.\n");
1146                 rndis_filter_device_remove(dev);
1147                 netvsc_free_netdev(net);
1148         } else {
1149                 schedule_delayed_work(&net_device_ctx->dwork, 0);
1150         }
1151
1152         return ret;
1153 }
1154
1155 static int netvsc_remove(struct hv_device *dev)
1156 {
1157         struct net_device *net;
1158         struct net_device_context *ndev_ctx;
1159         struct netvsc_device *net_device;
1160
1161         net_device = hv_get_drvdata(dev);
1162         net = net_device->ndev;
1163
1164         if (net == NULL) {
1165                 dev_err(&dev->device, "No net device to remove\n");
1166                 return 0;
1167         }
1168
1169         net_device->start_remove = true;
1170
1171         ndev_ctx = netdev_priv(net);
1172         cancel_delayed_work_sync(&ndev_ctx->dwork);
1173         cancel_work_sync(&ndev_ctx->work);
1174
1175         /* Stop outbound asap */
1176         netif_tx_disable(net);
1177
1178         unregister_netdev(net);
1179
1180         /*
1181          * Call to the vsc driver to let it know that the device is being
1182          * removed
1183          */
1184         rndis_filter_device_remove(dev);
1185
1186         netvsc_free_netdev(net);
1187         return 0;
1188 }
1189
1190 static const struct hv_vmbus_device_id id_table[] = {
1191         /* Network guid */
1192         { HV_NIC_GUID, },
1193         { },
1194 };
1195
1196 MODULE_DEVICE_TABLE(vmbus, id_table);
1197
1198 /* The one and only one */
1199 static struct  hv_driver netvsc_drv = {
1200         .name = KBUILD_MODNAME,
1201         .id_table = id_table,
1202         .probe = netvsc_probe,
1203         .remove = netvsc_remove,
1204 };
1205
1206 static void __exit netvsc_drv_exit(void)
1207 {
1208         vmbus_driver_unregister(&netvsc_drv);
1209 }
1210
1211 static int __init netvsc_drv_init(void)
1212 {
1213         if (ring_size < RING_SIZE_MIN) {
1214                 ring_size = RING_SIZE_MIN;
1215                 pr_info("Increased ring_size to %d (min allowed)\n",
1216                         ring_size);
1217         }
1218         return vmbus_driver_register(&netvsc_drv);
1219 }
1220
1221 MODULE_LICENSE("GPL");
1222 MODULE_DESCRIPTION("Microsoft Hyper-V network driver");
1223
1224 module_init(netvsc_drv_init);
1225 module_exit(netvsc_drv_exit);