drivers/net/hyperv/netvsc.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/kernel.h>
  23 #include <linux/sched.h>
  24 #include <linux/wait.h>
  25 #include <linux/mm.h>
  26 #include <linux/delay.h>
  27 #include <linux/io.h>
  28 #include <linux/slab.h>
  29 #include <linux/netdevice.h>
  30 #include <linux/if_ether.h>
  31 #include <asm/sync_bitops.h>
  32
  33 #include "hyperv_net.h"
  34
  35
  36 static struct netvsc_device *alloc_net_device(struct hv_device *device)
  37 {
  38         struct netvsc_device *net_device;
  39         struct net_device *ndev = hv_get_drvdata(device);
  40         int i;
  41
  42         net_device = kzalloc(sizeof(struct netvsc_device), GFP_KERNEL);
  43         if (!net_device)
  44                 return NULL;
  45
  46         net_device->cb_buffer = kzalloc(NETVSC_PACKET_SIZE, GFP_KERNEL);
  47         if (!net_device->cb_buffer) {
  48                 kfree(net_device);
  49                 return NULL;
  50         }
  51
  52         init_waitqueue_head(&net_device->wait_drain);
  53         net_device->start_remove = false;
  54         net_device->destroy = false;
  55         net_device->dev = device;
  56         net_device->ndev = ndev;
  57         net_device->max_pkt = RNDIS_MAX_PKT_DEFAULT;
  58         net_device->pkt_align = RNDIS_PKT_ALIGN_DEFAULT;
  59
  60         for (i = 0; i < num_online_cpus(); i++)
  61                 spin_lock_init(&net_device->msd[i].lock);
  62
  63         hv_set_drvdata(device, net_device);
  64         return net_device;
  65 }
  66
  67 static void free_netvsc_device(struct netvsc_device *nvdev)
  68 {
  69         kfree(nvdev->cb_buffer);
  70         kfree(nvdev);
  71 }
  72
  73 static struct netvsc_device *get_outbound_net_device(struct hv_device *device)
  74 {
  75         struct netvsc_device *net_device;
  76
  77         net_device = hv_get_drvdata(device);
  78         if (net_device && net_device->destroy)
  79                 net_device = NULL;
  80
  81         return net_device;
  82 }
  83
  84 static struct netvsc_device *get_inbound_net_device(struct hv_device *device)
  85 {
  86         struct netvsc_device *net_device;
  87
  88         net_device = hv_get_drvdata(device);
  89
  90         if (!net_device)
  91                 goto get_in_err;
  92
  93         if (net_device->destroy &&
  94                 atomic_read(&net_device->num_outstanding_sends) == 0)
  95                 net_device = NULL;
  96
  97 get_in_err:
  98         return net_device;
  99 }
 100
 101
 102 static int netvsc_destroy_buf(struct netvsc_device *net_device)
 103 {
 104         struct nvsp_message *revoke_packet;
 105         int ret = 0;
 106         struct net_device *ndev = net_device->ndev;
 107
 108         /*
 109          * If we got a section count, it means we received a
 110          * SendReceiveBufferComplete msg (ie sent
 111          * NvspMessage1TypeSendReceiveBuffer msg) therefore, we need
 112          * to send a revoke msg here
 113          */
 114         if (net_device->recv_section_cnt) {
 115                 /* Send the revoke receive buffer */
 116                 revoke_packet = &net_device->revoke_packet;
 117                 memset(revoke_packet, 0, sizeof(struct nvsp_message));
 118
 119                 revoke_packet->hdr.msg_type =
 120                         NVSP_MSG1_TYPE_REVOKE_RECV_BUF;
 121                 revoke_packet->msg.v1_msg.
 122                 revoke_recv_buf.id = NETVSC_RECEIVE_BUFFER_ID;
 123
 124                 ret = vmbus_sendpacket(net_device->dev->channel,
 125                                        revoke_packet,
 126                                        sizeof(struct nvsp_message),
 127                                        (unsigned long)revoke_packet,
 128                                        VM_PKT_DATA_INBAND, 0);
 129                 /*
 130                  * If we failed here, we might as well return and
 131                  * have a leak rather than continue and a bugchk
 132                  */
 133                 if (ret != 0) {
 134                         netdev_err(ndev, "unable to send "
 135                                 "revoke receive buffer to netvsp\n");
 136                         return ret;
 137                 }
 138         }
 139
 140         /* Teardown the gpadl on the vsp end */
 141         if (net_device->recv_buf_gpadl_handle) {
 142                 ret = vmbus_teardown_gpadl(net_device->dev->channel,
 143                            net_device->recv_buf_gpadl_handle);
 144
 145                 /* If we failed here, we might as well return and have a leak
 146                  * rather than continue and a bugchk
 147                  */
 148                 if (ret != 0) {
 149                         netdev_err(ndev,
 150                                    "unable to teardown receive buffer's gpadl\n");
 151                         return ret;
 152                 }
 153                 net_device->recv_buf_gpadl_handle = 0;
 154         }
 155
 156         if (net_device->recv_buf) {
 157                 /* Free up the receive buffer */
 158                 vfree(net_device->recv_buf);
 159                 net_device->recv_buf = NULL;
 160         }
 161
 162         if (net_device->recv_section) {
 163                 net_device->recv_section_cnt = 0;
 164                 kfree(net_device->recv_section);
 165                 net_device->recv_section = NULL;
 166         }
 167
 168         /* Deal with the send buffer we may have setup.
 169          * If we got a  send section size, it means we received a
 170          * NVSP_MSG1_TYPE_SEND_SEND_BUF_COMPLETE msg (ie sent
 171          * NVSP_MSG1_TYPE_SEND_SEND_BUF msg) therefore, we need
 172          * to send a revoke msg here
 173          */
 174         if (net_device->send_section_size) {
 175                 /* Send the revoke receive buffer */
 176                 revoke_packet = &net_device->revoke_packet;
 177                 memset(revoke_packet, 0, sizeof(struct nvsp_message));
 178
 179                 revoke_packet->hdr.msg_type =
 180                         NVSP_MSG1_TYPE_REVOKE_SEND_BUF;
 181                 revoke_packet->msg.v1_msg.revoke_send_buf.id =
 182                         NETVSC_SEND_BUFFER_ID;
 183
 184                 ret = vmbus_sendpacket(net_device->dev->channel,
 185                                        revoke_packet,
 186                                        sizeof(struct nvsp_message),
 187                                        (unsigned long)revoke_packet,
 188                                        VM_PKT_DATA_INBAND, 0);
 189                 /* If we failed here, we might as well return and
 190                  * have a leak rather than continue and a bugchk
 191                  */
 192                 if (ret != 0) {
 193                         netdev_err(ndev, "unable to send "
 194                                    "revoke send buffer to netvsp\n");
 195                         return ret;
 196                 }
 197         }
 198         /* Teardown the gpadl on the vsp end */
 199         if (net_device->send_buf_gpadl_handle) {
 200                 ret = vmbus_teardown_gpadl(net_device->dev->channel,
 201                                            net_device->send_buf_gpadl_handle);
 202
 203                 /* If we failed here, we might as well return and have a leak
 204                  * rather than continue and a bugchk
 205                  */
 206                 if (ret != 0) {
 207                         netdev_err(ndev,
 208                                    "unable to teardown send buffer's gpadl\n");
 209                         return ret;
 210                 }
 211                 net_device->send_buf_gpadl_handle = 0;
 212         }
 213         if (net_device->send_buf) {
 214                 /* Free up the send buffer */
 215                 vfree(net_device->send_buf);
 216                 net_device->send_buf = NULL;
 217         }
 218         kfree(net_device->send_section_map);
 219
 220         return ret;
 221 }
 222
 223 static int netvsc_init_buf(struct hv_device *device)
 224 {
 225         int ret = 0;
 226         unsigned long t;
 227         struct netvsc_device *net_device;
 228         struct nvsp_message *init_packet;
 229         struct net_device *ndev;
 230
 231         net_device = get_outbound_net_device(device);
 232         if (!net_device)
 233                 return -ENODEV;
 234         ndev = net_device->ndev;
 235
 236         net_device->recv_buf = vzalloc(net_device->recv_buf_size);
 237         if (!net_device->recv_buf) {
 238                 netdev_err(ndev, "unable to allocate receive "
 239                         "buffer of size %d\n", net_device->recv_buf_size);
 240                 ret = -ENOMEM;
 241                 goto cleanup;
 242         }
 243
 244         /*
 245          * Establish the gpadl handle for this buffer on this
 246          * channel.  Note: This call uses the vmbus connection rather
 247          * than the channel to establish the gpadl handle.
 248          */
 249         ret = vmbus_establish_gpadl(device->channel, net_device->recv_buf,
 250                                     net_device->recv_buf_size,
 251                                     &net_device->recv_buf_gpadl_handle);
 252         if (ret != 0) {
 253                 netdev_err(ndev,
 254                         "unable to establish receive buffer's gpadl\n");
 255                 goto cleanup;
 256         }
 257
 258
 259         /* Notify the NetVsp of the gpadl handle */
 260         init_packet = &net_device->channel_init_pkt;
 261
 262         memset(init_packet, 0, sizeof(struct nvsp_message));
 263
 264         init_packet->hdr.msg_type = NVSP_MSG1_TYPE_SEND_RECV_BUF;
 265         init_packet->msg.v1_msg.send_recv_buf.
 266                 gpadl_handle = net_device->recv_buf_gpadl_handle;
 267         init_packet->msg.v1_msg.
 268                 send_recv_buf.id = NETVSC_RECEIVE_BUFFER_ID;
 269
 270         /* Send the gpadl notification request */
 271         ret = vmbus_sendpacket(device->channel, init_packet,
 272                                sizeof(struct nvsp_message),
 273                                (unsigned long)init_packet,
 274                                VM_PKT_DATA_INBAND,
 275                                VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
 276         if (ret != 0) {
 277                 netdev_err(ndev,
 278                         "unable to send receive buffer's gpadl to netvsp\n");
 279                 goto cleanup;
 280         }
 281
 282         t = wait_for_completion_timeout(&net_device->channel_init_wait, 5*HZ);
 283         BUG_ON(t == 0);
 284
 285
 286         /* Check the response */
 287         if (init_packet->msg.v1_msg.
 288             send_recv_buf_complete.status != NVSP_STAT_SUCCESS) {
 289                 netdev_err(ndev, "Unable to complete receive buffer "
 290                            "initialization with NetVsp - status %d\n",
 291                            init_packet->msg.v1_msg.
 292                            send_recv_buf_complete.status);
 293                 ret = -EINVAL;
 294                 goto cleanup;
 295         }
 296
 297         /* Parse the response */
 298
 299         net_device->recv_section_cnt = init_packet->msg.
 300                 v1_msg.send_recv_buf_complete.num_sections;
 301
 302         net_device->recv_section = kmemdup(
 303                 init_packet->msg.v1_msg.send_recv_buf_complete.sections,
 304                 net_device->recv_section_cnt *
 305                 sizeof(struct nvsp_1_receive_buffer_section),
 306                 GFP_KERNEL);
 307         if (net_device->recv_section == NULL) {
 308                 ret = -EINVAL;
 309                 goto cleanup;
 310         }
 311
 312         /*
 313          * For 1st release, there should only be 1 section that represents the
 314          * entire receive buffer
 315          */
 316         if (net_device->recv_section_cnt != 1 ||
 317             net_device->recv_section->offset != 0) {
 318                 ret = -EINVAL;
 319                 goto cleanup;
 320         }
 321
 322         /* Now setup the send buffer.
 323          */
 324         net_device->send_buf = vzalloc(net_device->send_buf_size);
 325         if (!net_device->send_buf) {
 326                 netdev_err(ndev, "unable to allocate send "
 327                            "buffer of size %d\n", net_device->send_buf_size);
 328                 ret = -ENOMEM;
 329                 goto cleanup;
 330         }
 331
 332         /* Establish the gpadl handle for this buffer on this
 333          * channel.  Note: This call uses the vmbus connection rather
 334          * than the channel to establish the gpadl handle.
 335          */
 336         ret = vmbus_establish_gpadl(device->channel, net_device->send_buf,
 337                                     net_device->send_buf_size,
 338                                     &net_device->send_buf_gpadl_handle);
 339         if (ret != 0) {
 340                 netdev_err(ndev,
 341                            "unable to establish send buffer's gpadl\n");
 342                 goto cleanup;
 343         }
 344
 345         /* Notify the NetVsp of the gpadl handle */
 346         init_packet = &net_device->channel_init_pkt;
 347         memset(init_packet, 0, sizeof(struct nvsp_message));
 348         init_packet->hdr.msg_type = NVSP_MSG1_TYPE_SEND_SEND_BUF;
 349         init_packet->msg.v1_msg.send_send_buf.gpadl_handle =
 350                 net_device->send_buf_gpadl_handle;
 351         init_packet->msg.v1_msg.send_send_buf.id = NETVSC_SEND_BUFFER_ID;
 352
 353         /* Send the gpadl notification request */
 354         ret = vmbus_sendpacket(device->channel, init_packet,
 355                                sizeof(struct nvsp_message),
 356                                (unsigned long)init_packet,
 357                                VM_PKT_DATA_INBAND,
 358                                VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
 359         if (ret != 0) {
 360                 netdev_err(ndev,
 361                            "unable to send send buffer's gpadl to netvsp\n");
 362                 goto cleanup;
 363         }
 364
 365         t = wait_for_completion_timeout(&net_device->channel_init_wait, 5*HZ);
 366         BUG_ON(t == 0);
 367
 368         /* Check the response */
 369         if (init_packet->msg.v1_msg.
 370             send_send_buf_complete.status != NVSP_STAT_SUCCESS) {
 371                 netdev_err(ndev, "Unable to complete send buffer "
 372                            "initialization with NetVsp - status %d\n",
 373                            init_packet->msg.v1_msg.
 374                            send_send_buf_complete.status);
 375                 ret = -EINVAL;
 376                 goto cleanup;
 377         }
 378
 379         /* Parse the response */
 380         net_device->send_section_size = init_packet->msg.
 381                                 v1_msg.send_send_buf_complete.section_size;
 382
 383         /* Section count is simply the size divided by the section size.
 384          */
 385         net_device->send_section_cnt =
 386                 net_device->send_buf_size/net_device->send_section_size;
 387
 388         dev_info(&device->device, "Send section size: %d, Section count:%d\n",
 389                  net_device->send_section_size, net_device->send_section_cnt);
 390
 391         /* Setup state for managing the send buffer. */
 392         net_device->map_words = DIV_ROUND_UP(net_device->send_section_cnt,
 393                                              BITS_PER_LONG);
 394
 395         net_device->send_section_map =
 396                 kzalloc(net_device->map_words * sizeof(ulong), GFP_KERNEL);
 397         if (net_device->send_section_map == NULL) {
 398                 ret = -ENOMEM;
 399                 goto cleanup;
 400         }
 401
 402         goto exit;
 403
 404 cleanup:
 405         netvsc_destroy_buf(net_device);
 406
 407 exit:
 408         return ret;
 409 }
 410
 411
 412 /* Negotiate NVSP protocol version */
 413 static int negotiate_nvsp_ver(struct hv_device *device,
 414                               struct netvsc_device *net_device,
 415                               struct nvsp_message *init_packet,
 416                               u32 nvsp_ver)
 417 {
 418         int ret;
 419         unsigned long t;
 420
 421         memset(init_packet, 0, sizeof(struct nvsp_message));
 422         init_packet->hdr.msg_type = NVSP_MSG_TYPE_INIT;
 423         init_packet->msg.init_msg.init.min_protocol_ver = nvsp_ver;
 424         init_packet->msg.init_msg.init.max_protocol_ver = nvsp_ver;
 425
 426         /* Send the init request */
 427         ret = vmbus_sendpacket(device->channel, init_packet,
 428                                sizeof(struct nvsp_message),
 429                                (unsigned long)init_packet,
 430                                VM_PKT_DATA_INBAND,
 431                                VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
 432
 433         if (ret != 0)
 434                 return ret;
 435
 436         t = wait_for_completion_timeout(&net_device->channel_init_wait, 5*HZ);
 437
 438         if (t == 0)
 439                 return -ETIMEDOUT;
 440
 441         if (init_packet->msg.init_msg.init_complete.status !=
 442             NVSP_STAT_SUCCESS)
 443                 return -EINVAL;
 444
 445         if (nvsp_ver == NVSP_PROTOCOL_VERSION_1)
 446                 return 0;
 447
 448         /* NVSPv2 only: Send NDIS config */
 449         memset(init_packet, 0, sizeof(struct nvsp_message));
 450         init_packet->hdr.msg_type = NVSP_MSG2_TYPE_SEND_NDIS_CONFIG;
 451         init_packet->msg.v2_msg.send_ndis_config.mtu = net_device->ndev->mtu +
 452                                                        ETH_HLEN;
 453         init_packet->msg.v2_msg.send_ndis_config.capability.ieee8021q = 1;
 454
 455         ret = vmbus_sendpacket(device->channel, init_packet,
 456                                 sizeof(struct nvsp_message),
 457                                 (unsigned long)init_packet,
 458                                 VM_PKT_DATA_INBAND, 0);
 459
 460         return ret;
 461 }
 462
 463 static int netvsc_connect_vsp(struct hv_device *device)
 464 {
 465         int ret;
 466         struct netvsc_device *net_device;
 467         struct nvsp_message *init_packet;
 468         int ndis_version;
 469         struct net_device *ndev;
 470         u32 ver_list[] = { NVSP_PROTOCOL_VERSION_1, NVSP_PROTOCOL_VERSION_2,
 471                 NVSP_PROTOCOL_VERSION_4, NVSP_PROTOCOL_VERSION_5 };
 472         int i, num_ver = 4; /* number of different NVSP versions */
 473
 474         net_device = get_outbound_net_device(device);
 475         if (!net_device)
 476                 return -ENODEV;
 477         ndev = net_device->ndev;
 478
 479         init_packet = &net_device->channel_init_pkt;
 480
 481         /* Negotiate the latest NVSP protocol supported */
 482         for (i = num_ver - 1; i >= 0; i--)
 483                 if (negotiate_nvsp_ver(device, net_device, init_packet,
 484                                        ver_list[i])  == 0) {
 485                         net_device->nvsp_version = ver_list[i];
 486                         break;
 487                 }
 488
 489         if (i < 0) {
 490                 ret = -EPROTO;
 491                 goto cleanup;
 492         }
 493
 494         pr_debug("Negotiated NVSP version:%x\n", net_device->nvsp_version);
 495
 496         /* Send the ndis version */
 497         memset(init_packet, 0, sizeof(struct nvsp_message));
 498
 499         if (net_device->nvsp_version <= NVSP_PROTOCOL_VERSION_4)
 500                 ndis_version = 0x00060001;
 501         else
 502                 ndis_version = 0x0006001e;
 503
 504         init_packet->hdr.msg_type = NVSP_MSG1_TYPE_SEND_NDIS_VER;
 505         init_packet->msg.v1_msg.
 506                 send_ndis_ver.ndis_major_ver =
 507                                 (ndis_version & 0xFFFF0000) >> 16;
 508         init_packet->msg.v1_msg.
 509                 send_ndis_ver.ndis_minor_ver =
 510                                 ndis_version & 0xFFFF;
 511
 512         /* Send the init request */
 513         ret = vmbus_sendpacket(device->channel, init_packet,
 514                                 sizeof(struct nvsp_message),
 515                                 (unsigned long)init_packet,
 516                                 VM_PKT_DATA_INBAND, 0);
 517         if (ret != 0)
 518                 goto cleanup;
 519
 520         /* Post the big receive buffer to NetVSP */
 521         if (net_device->nvsp_version <= NVSP_PROTOCOL_VERSION_2)
 522                 net_device->recv_buf_size = NETVSC_RECEIVE_BUFFER_SIZE_LEGACY;
 523         else
 524                 net_device->recv_buf_size = NETVSC_RECEIVE_BUFFER_SIZE;
 525         net_device->send_buf_size = NETVSC_SEND_BUFFER_SIZE;
 526
 527         ret = netvsc_init_buf(device);
 528
 529 cleanup:
 530         return ret;
 531 }
 532
 533 static void netvsc_disconnect_vsp(struct netvsc_device *net_device)
 534 {
 535         netvsc_destroy_buf(net_device);
 536 }
 537
 538 /*
 539  * netvsc_device_remove - Callback when the root bus device is removed
 540  */
 541 int netvsc_device_remove(struct hv_device *device)
 542 {
 543         struct netvsc_device *net_device;
 544         unsigned long flags;
 545
 546         net_device = hv_get_drvdata(device);
 547
 548         netvsc_disconnect_vsp(net_device);
 549
 550         /*
 551          * Since we have already drained, we don't need to busy wait
 552          * as was done in final_release_stor_device()
 553          * Note that we cannot set the ext pointer to NULL until
 554          * we have drained - to drain the outgoing packets, we need to
 555          * allow incoming packets.
 556          */
 557
 558         spin_lock_irqsave(&device->channel->inbound_lock, flags);
 559         hv_set_drvdata(device, NULL);
 560         spin_unlock_irqrestore(&device->channel->inbound_lock, flags);
 561
 562         /*
 563          * At this point, no one should be accessing net_device
 564          * except in here
 565          */
 566         dev_notice(&device->device, "net device safe to remove\n");
 567
 568         /* Now, we can close the channel safely */
 569         vmbus_close(device->channel);
 570
 571         /* Release all resources */
 572         vfree(net_device->sub_cb_buf);
 573         free_netvsc_device(net_device);
 574         return 0;
 575 }
 576
 577
 578 #define RING_AVAIL_PERCENT_HIWATER 20
 579 #define RING_AVAIL_PERCENT_LOWATER 10
 580
 581 /*
 582  * Get the percentage of available bytes to write in the ring.
 583  * The return value is in range from 0 to 100.
 584  */
 585 static inline u32 hv_ringbuf_avail_percent(
 586                 struct hv_ring_buffer_info *ring_info)
 587 {
 588         u32 avail_read, avail_write;
 589
 590         hv_get_ringbuffer_availbytes(ring_info, &avail_read, &avail_write);
 591
 592         return avail_write * 100 / ring_info->ring_datasize;
 593 }
 594
 595 static inline void netvsc_free_send_slot(struct netvsc_device *net_device,
 596                                          u32 index)
 597 {
 598         sync_change_bit(index, net_device->send_section_map);
 599 }
 600
 601 static void netvsc_send_completion(struct netvsc_device *net_device,
 602                                    struct hv_device *device,
 603                                    struct vmpacket_descriptor *packet)
 604 {
 605         struct nvsp_message *nvsp_packet;
 606         struct hv_netvsc_packet *nvsc_packet;
 607         struct net_device *ndev;
 608         u32 send_index;
 609
 610         ndev = net_device->ndev;
 611
 612         nvsp_packet = (struct nvsp_message *)((unsigned long)packet +
 613                         (packet->offset8 << 3));
 614
 615         if ((nvsp_packet->hdr.msg_type == NVSP_MSG_TYPE_INIT_COMPLETE) ||
 616             (nvsp_packet->hdr.msg_type ==
 617              NVSP_MSG1_TYPE_SEND_RECV_BUF_COMPLETE) ||
 618             (nvsp_packet->hdr.msg_type ==
 619              NVSP_MSG1_TYPE_SEND_SEND_BUF_COMPLETE) ||
 620             (nvsp_packet->hdr.msg_type ==
 621              NVSP_MSG5_TYPE_SUBCHANNEL)) {
 622                 /* Copy the response back */
 623                 memcpy(&net_device->channel_init_pkt, nvsp_packet,
 624                        sizeof(struct nvsp_message));
 625                 complete(&net_device->channel_init_wait);
 626         } else if (nvsp_packet->hdr.msg_type ==
 627                    NVSP_MSG1_TYPE_SEND_RNDIS_PKT_COMPLETE) {
 628                 int num_outstanding_sends;
 629                 u16 q_idx = 0;
 630                 struct vmbus_channel *channel = device->channel;
 631                 int queue_sends;
 632
 633                 /* Get the send context */
 634                 nvsc_packet = (struct hv_netvsc_packet *)(unsigned long)
 635                         packet->trans_id;
 636
 637                 /* Notify the layer above us */
 638                 if (nvsc_packet) {
 639                         send_index = nvsc_packet->send_buf_index;
 640                         if (send_index != NETVSC_INVALID_INDEX)
 641                                 netvsc_free_send_slot(net_device, send_index);
 642                         q_idx = nvsc_packet->q_idx;
 643                         channel = nvsc_packet->channel;
 644                         nvsc_packet->send_completion(nvsc_packet->
 645                                                      send_completion_ctx);
 646                 }
 647
 648                 num_outstanding_sends =
 649                         atomic_dec_return(&net_device->num_outstanding_sends);
 650                 queue_sends = atomic_dec_return(&net_device->
 651                                                 queue_sends[q_idx]);
 652
 653                 if (net_device->destroy && num_outstanding_sends == 0)
 654                         wake_up(&net_device->wait_drain);
 655
 656                 if (netif_tx_queue_stopped(netdev_get_tx_queue(ndev, q_idx)) &&
 657                     !net_device->start_remove &&
 658                     (hv_ringbuf_avail_percent(&channel->outbound) >
 659                      RING_AVAIL_PERCENT_HIWATER || queue_sends < 1))
 660                                 netif_tx_wake_queue(netdev_get_tx_queue(
 661                                                     ndev, q_idx));
 662         } else {
 663                 netdev_err(ndev, "Unknown send completion packet type- "
 664                            "%d received!!\n", nvsp_packet->hdr.msg_type);
 665         }
 666
 667 }
 668
 669 static u32 netvsc_get_next_send_section(struct netvsc_device *net_device)
 670 {
 671         unsigned long index;
 672         u32 max_words = net_device->map_words;
 673         unsigned long *map_addr = (unsigned long *)net_device->send_section_map;
 674         u32 section_cnt = net_device->send_section_cnt;
 675         int ret_val = NETVSC_INVALID_INDEX;
 676         int i;
 677         int prev_val;
 678
 679         for (i = 0; i < max_words; i++) {
 680                 if (!~(map_addr[i]))
 681                         continue;
 682                 index = ffz(map_addr[i]);
 683                 prev_val = sync_test_and_set_bit(index, &map_addr[i]);
 684                 if (prev_val)
 685                         continue;
 686                 if ((index + (i * BITS_PER_LONG)) >= section_cnt)
 687                         break;
 688                 ret_val = (index + (i * BITS_PER_LONG));
 689                 break;
 690         }
 691         return ret_val;
 692 }
 693
 694 static u32 netvsc_copy_to_send_buf(struct netvsc_device *net_device,
 695                                    unsigned int section_index,
 696                                    u32 pend_size,
 697                                    struct hv_netvsc_packet *packet)
 698 {
 699         char *start = net_device->send_buf;
 700         char *dest = start + (section_index * net_device->send_section_size)
 701                      + pend_size;
 702         int i;
 703         u32 msg_size = 0;
 704         u32 padding = 0;
 705         u32 remain = packet->total_data_buflen % net_device->pkt_align;
 706         u32 page_count = packet->cp_partial ? packet->rmsg_pgcnt :
 707                 packet->page_buf_cnt;
 708
 709         /* Add padding */
 710         if (packet->is_data_pkt && packet->xmit_more && remain &&
 711             !packet->cp_partial) {
 712                 padding = net_device->pkt_align - remain;
 713                 packet->rndis_msg->msg_len += padding;
 714                 packet->total_data_buflen += padding;
 715         }
 716
 717         for (i = 0; i < page_count; i++) {
 718                 char *src = phys_to_virt(packet->page_buf[i].pfn << PAGE_SHIFT);
 719                 u32 offset = packet->page_buf[i].offset;
 720                 u32 len = packet->page_buf[i].len;
 721
 722                 memcpy(dest, (src + offset), len);
 723                 msg_size += len;
 724                 dest += len;
 725         }
 726
 727         if (padding) {
 728                 memset(dest, 0, padding);
 729                 msg_size += padding;
 730         }
 731
 732         return msg_size;
 733 }
 734
 735 static inline int netvsc_send_pkt(
 736         struct hv_netvsc_packet *packet,
 737         struct netvsc_device *net_device)
 738 {
 739         struct nvsp_message nvmsg;
 740         struct vmbus_channel *out_channel = packet->channel;
 741         u16 q_idx = packet->q_idx;
 742         struct net_device *ndev = net_device->ndev;
 743         u64 req_id;
 744         int ret;
 745         struct hv_page_buffer *pgbuf;
 746
 747         nvmsg.hdr.msg_type = NVSP_MSG1_TYPE_SEND_RNDIS_PKT;
 748         if (packet->is_data_pkt) {
 749                 /* 0 is RMC_DATA; */
 750                 nvmsg.msg.v1_msg.send_rndis_pkt.channel_type = 0;
 751         } else {
 752                 /* 1 is RMC_CONTROL; */
 753                 nvmsg.msg.v1_msg.send_rndis_pkt.channel_type = 1;
 754         }
 755
 756         nvmsg.msg.v1_msg.send_rndis_pkt.send_buf_section_index =
 757                 packet->send_buf_index;
 758         if (packet->send_buf_index == NETVSC_INVALID_INDEX)
 759                 nvmsg.msg.v1_msg.send_rndis_pkt.send_buf_section_size = 0;
 760         else
 761                 nvmsg.msg.v1_msg.send_rndis_pkt.send_buf_section_size =
 762                         packet->total_data_buflen;
 763
 764         if (packet->send_completion)
 765                 req_id = (ulong)packet;
 766         else
 767                 req_id = 0;
 768
 769         if (out_channel->rescind)
 770                 return -ENODEV;
 771
 772         if (packet->page_buf_cnt) {
 773                 pgbuf = packet->cp_partial ? packet->page_buf +
 774                         packet->rmsg_pgcnt : packet->page_buf;
 775                 ret = vmbus_sendpacket_pagebuffer(out_channel,
 776                                                   pgbuf,
 777                                                   packet->page_buf_cnt,
 778                                                   &nvmsg,
 779                                                   sizeof(struct nvsp_message),
 780                                                   req_id);
 781         } else {
 782                 ret = vmbus_sendpacket(
 783                                 out_channel, &nvmsg,
 784                                 sizeof(struct nvsp_message),
 785                                 req_id,
 786                                 VM_PKT_DATA_INBAND,
 787                                 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
 788         }
 789
 790         if (ret == 0) {
 791                 atomic_inc(&net_device->num_outstanding_sends);
 792                 atomic_inc(&net_device->queue_sends[q_idx]);
 793
 794                 if (hv_ringbuf_avail_percent(&out_channel->outbound) <
 795                         RING_AVAIL_PERCENT_LOWATER) {
 796                         netif_tx_stop_queue(netdev_get_tx_queue(
 797                                             ndev, q_idx));
 798
 799                         if (atomic_read(&net_device->
 800                                 queue_sends[q_idx]) < 1)
 801                                 netif_tx_wake_queue(netdev_get_tx_queue(
 802                                                     ndev, q_idx));
 803                 }
 804         } else if (ret == -EAGAIN) {
 805                 netif_tx_stop_queue(netdev_get_tx_queue(
 806                                     ndev, q_idx));
 807                 if (atomic_read(&net_device->queue_sends[q_idx]) < 1) {
 808                         netif_tx_wake_queue(netdev_get_tx_queue(
 809                                             ndev, q_idx));
 810                         ret = -ENOSPC;
 811                 }
 812         } else {
 813                 netdev_err(ndev, "Unable to send packet %p ret %d\n",
 814                            packet, ret);
 815         }
 816
 817         return ret;
 818 }
 819
 820 int netvsc_send(struct hv_device *device,
 821                 struct hv_netvsc_packet *packet)
 822 {
 823         struct netvsc_device *net_device;
 824         int ret = 0, m_ret = 0;
 825         struct vmbus_channel *out_channel;
 826         u16 q_idx = packet->q_idx;
 827         u32 pktlen = packet->total_data_buflen, msd_len = 0;
 828         unsigned int section_index = NETVSC_INVALID_INDEX;
 829         unsigned long flag;
 830         struct multi_send_data *msdp;
 831         struct hv_netvsc_packet *msd_send = NULL, *cur_send = NULL;
 832         bool try_batch;
 833
 834         net_device = get_outbound_net_device(device);
 835         if (!net_device)
 836                 return -ENODEV;
 837
 838         out_channel = net_device->chn_table[q_idx];
 839         if (!out_channel) {
 840                 out_channel = device->channel;
 841                 q_idx = 0;
 842                 packet->q_idx = 0;
 843         }
 844         packet->channel = out_channel;
 845         packet->send_buf_index = NETVSC_INVALID_INDEX;
 846         packet->cp_partial = false;
 847
 848         msdp = &net_device->msd[q_idx];
 849
 850         /* batch packets in send buffer if possible */
 851         spin_lock_irqsave(&msdp->lock, flag);
 852         if (msdp->pkt)
 853                 msd_len = msdp->pkt->total_data_buflen;
 854
 855         try_batch = packet->is_data_pkt && msd_len > 0 && msdp->count <
 856                     net_device->max_pkt;
 857
 858         if (try_batch && msd_len + pktlen + net_device->pkt_align <
 859             net_device->send_section_size) {
 860                 section_index = msdp->pkt->send_buf_index;
 861
 862         } else if (try_batch && msd_len + packet->rmsg_size <
 863                    net_device->send_section_size) {
 864                 section_index = msdp->pkt->send_buf_index;
 865                 packet->cp_partial = true;
 866
 867         } else if (packet->is_data_pkt && pktlen + net_device->pkt_align <
 868                    net_device->send_section_size) {
 869                 section_index = netvsc_get_next_send_section(net_device);
 870                 if (section_index != NETVSC_INVALID_INDEX) {
 871                                 msd_send = msdp->pkt;
 872                                 msdp->pkt = NULL;
 873                                 msdp->count = 0;
 874                                 msd_len = 0;
 875                 }
 876         }
 877
 878         if (section_index != NETVSC_INVALID_INDEX) {
 879                 netvsc_copy_to_send_buf(net_device,
 880                                         section_index, msd_len,
 881                                         packet);
 882
 883                 packet->send_buf_index = section_index;
 884
 885                 if (packet->cp_partial) {
 886                         packet->page_buf_cnt -= packet->rmsg_pgcnt;
 887                         packet->total_data_buflen = msd_len + packet->rmsg_size;
 888                 } else {
 889                         packet->page_buf_cnt = 0;
 890                         packet->total_data_buflen += msd_len;
 891                 }
 892
 893                 if (msdp->pkt)
 894                         netvsc_xmit_completion(msdp->pkt);
 895
 896                 if (packet->xmit_more && !packet->cp_partial) {
 897                         msdp->pkt = packet;
 898                         msdp->count++;
 899                 } else {
 900                         cur_send = packet;
 901                         msdp->pkt = NULL;
 902                         msdp->count = 0;
 903                 }
 904         } else {
 905                 msd_send = msdp->pkt;
 906                 msdp->pkt = NULL;
 907                 msdp->count = 0;
 908                 cur_send = packet;
 909         }
 910
 911         spin_unlock_irqrestore(&msdp->lock, flag);
 912
 913         if (msd_send) {
 914                 m_ret = netvsc_send_pkt(msd_send, net_device);
 915
 916                 if (m_ret != 0) {
 917                         netvsc_free_send_slot(net_device,
 918                                               msd_send->send_buf_index);
 919                         netvsc_xmit_completion(msd_send);
 920                 }
 921         }
 922
 923         if (cur_send)
 924                 ret = netvsc_send_pkt(cur_send, net_device);
 925
 926         if (ret != 0 && section_index != NETVSC_INVALID_INDEX)
 927                 netvsc_free_send_slot(net_device, section_index);
 928
 929         return ret;
 930 }
 931
 932 static void netvsc_send_recv_completion(struct hv_device *device,
 933                                         struct vmbus_channel *channel,
 934                                         struct netvsc_device *net_device,
 935                                         u64 transaction_id, u32 status)
 936 {
 937         struct nvsp_message recvcompMessage;
 938         int retries = 0;
 939         int ret;
 940         struct net_device *ndev;
 941
 942         ndev = net_device->ndev;
 943
 944         recvcompMessage.hdr.msg_type =
 945                                 NVSP_MSG1_TYPE_SEND_RNDIS_PKT_COMPLETE;
 946
 947         recvcompMessage.msg.v1_msg.send_rndis_pkt_complete.status = status;
 948
 949 retry_send_cmplt:
 950         /* Send the completion */
 951         ret = vmbus_sendpacket(channel, &recvcompMessage,
 952                                sizeof(struct nvsp_message), transaction_id,
 953                                VM_PKT_COMP, 0);
 954         if (ret == 0) {
 955                 /* success */
 956                 /* no-op */
 957         } else if (ret == -EAGAIN) {
 958                 /* no more room...wait a bit and attempt to retry 3 times */
 959                 retries++;
 960                 netdev_err(ndev, "unable to send receive completion pkt"
 961                         " (tid %llx)...retrying %d\n", transaction_id, retries);
 962
 963                 if (retries < 4) {
 964                         udelay(100);
 965                         goto retry_send_cmplt;
 966                 } else {
 967                         netdev_err(ndev, "unable to send receive "
 968                                 "completion pkt (tid %llx)...give up retrying\n",
 969                                 transaction_id);
 970                 }
 971         } else {
 972                 netdev_err(ndev, "unable to send receive "
 973                         "completion pkt - %llx\n", transaction_id);
 974         }
 975 }
 976
 977 static void netvsc_receive(struct netvsc_device *net_device,
 978                         struct vmbus_channel *channel,
 979                         struct hv_device *device,
 980                         struct vmpacket_descriptor *packet)
 981 {
 982         struct vmtransfer_page_packet_header *vmxferpage_packet;
 983         struct nvsp_message *nvsp_packet;
 984         struct hv_netvsc_packet nv_pkt;
 985         struct hv_netvsc_packet *netvsc_packet = &nv_pkt;
 986         u32 status = NVSP_STAT_SUCCESS;
 987         int i;
 988         int count = 0;
 989         struct net_device *ndev;
 990
 991         ndev = net_device->ndev;
 992
 993         /*
 994          * All inbound packets other than send completion should be xfer page
 995          * packet
 996          */
 997         if (packet->type != VM_PKT_DATA_USING_XFER_PAGES) {
 998                 netdev_err(ndev, "Unknown packet type received - %d\n",
 999                            packet->type);
1000                 return;
1001         }
1002
1003         nvsp_packet = (struct nvsp_message *)((unsigned long)packet +
1004                         (packet->offset8 << 3));
1005
1006         /* Make sure this is a valid nvsp packet */
1007         if (nvsp_packet->hdr.msg_type !=
1008             NVSP_MSG1_TYPE_SEND_RNDIS_PKT) {
1009                 netdev_err(ndev, "Unknown nvsp packet type received-"
1010                         " %d\n", nvsp_packet->hdr.msg_type);
1011                 return;
1012         }
1013
1014         vmxferpage_packet = (struct vmtransfer_page_packet_header *)packet;
1015
1016         if (vmxferpage_packet->xfer_pageset_id != NETVSC_RECEIVE_BUFFER_ID) {
1017                 netdev_err(ndev, "Invalid xfer page set id - "
1018                            "expecting %x got %x\n", NETVSC_RECEIVE_BUFFER_ID,
1019                            vmxferpage_packet->xfer_pageset_id);
1020                 return;
1021         }
1022
1023         count = vmxferpage_packet->range_cnt;
1024         netvsc_packet->channel = channel;
1025
1026         /* Each range represents 1 RNDIS pkt that contains 1 ethernet frame */
1027         for (i = 0; i < count; i++) {
1028                 /* Initialize the netvsc packet */
1029                 netvsc_packet->status = NVSP_STAT_SUCCESS;
1030                 netvsc_packet->data = (void *)((unsigned long)net_device->
1031                         recv_buf + vmxferpage_packet->ranges[i].byte_offset);
1032                 netvsc_packet->total_data_buflen =
1033                                         vmxferpage_packet->ranges[i].byte_count;
1034
1035                 /* Pass it to the upper layer */
1036                 rndis_filter_receive(device, netvsc_packet);
1037
1038                 if (netvsc_packet->status != NVSP_STAT_SUCCESS)
1039                         status = NVSP_STAT_FAIL;
1040         }
1041
1042         netvsc_send_recv_completion(device, channel, net_device,
1043                                     vmxferpage_packet->d.trans_id, status);
1044 }
1045
1046
1047 static void netvsc_send_table(struct hv_device *hdev,
1048                               struct vmpacket_descriptor *vmpkt)
1049 {
1050         struct netvsc_device *nvscdev;
1051         struct net_device *ndev;
1052         struct nvsp_message *nvmsg;
1053         int i;
1054         u32 count, *tab;
1055
1056         nvscdev = get_outbound_net_device(hdev);
1057         if (!nvscdev)
1058                 return;
1059         ndev = nvscdev->ndev;
1060
1061         nvmsg = (struct nvsp_message *)((unsigned long)vmpkt +
1062                                         (vmpkt->offset8 << 3));
1063
1064         if (nvmsg->hdr.msg_type != NVSP_MSG5_TYPE_SEND_INDIRECTION_TABLE)
1065                 return;
1066
1067         count = nvmsg->msg.v5_msg.send_table.count;
1068         if (count != VRSS_SEND_TAB_SIZE) {
1069                 netdev_err(ndev, "Received wrong send-table size:%u\n", count);
1070                 return;
1071         }
1072
1073         tab = (u32 *)((unsigned long)&nvmsg->msg.v5_msg.send_table +
1074                       nvmsg->msg.v5_msg.send_table.offset);
1075
1076         for (i = 0; i < count; i++)
1077                 nvscdev->send_table[i] = tab[i];
1078 }
1079
1080 void netvsc_channel_cb(void *context)
1081 {
1082         int ret;
1083         struct vmbus_channel *channel = (struct vmbus_channel *)context;
1084         struct hv_device *device;
1085         struct netvsc_device *net_device;
1086         u32 bytes_recvd;
1087         u64 request_id;
1088         struct vmpacket_descriptor *desc;
1089         unsigned char *buffer;
1090         int bufferlen = NETVSC_PACKET_SIZE;
1091         struct net_device *ndev;
1092
1093         if (channel->primary_channel != NULL)
1094                 device = channel->primary_channel->device_obj;
1095         else
1096                 device = channel->device_obj;
1097
1098         net_device = get_inbound_net_device(device);
1099         if (!net_device)
1100                 return;
1101         ndev = net_device->ndev;
1102         buffer = get_per_channel_state(channel);
1103
1104         do {
1105                 ret = vmbus_recvpacket_raw(channel, buffer, bufferlen,
1106                                            &bytes_recvd, &request_id);
1107                 if (ret == 0) {
1108                         if (bytes_recvd > 0) {
1109                                 desc = (struct vmpacket_descriptor *)buffer;
1110                                 switch (desc->type) {
1111                                 case VM_PKT_COMP:
1112                                         netvsc_send_completion(net_device,
1113                                                                 device, desc);
1114                                         break;
1115
1116                                 case VM_PKT_DATA_USING_XFER_PAGES:
1117                                         netvsc_receive(net_device, channel,
1118                                                        device, desc);
1119                                         break;
1120
1121                                 case VM_PKT_DATA_INBAND:
1122                                         netvsc_send_table(device, desc);
1123                                         break;
1124
1125                                 default:
1126                                         netdev_err(ndev,
1127                                                    "unhandled packet type %d, "
1128                                                    "tid %llx len %d\n",
1129                                                    desc->type, request_id,
1130                                                    bytes_recvd);
1131                                         break;
1132                                 }
1133
1134                         } else {
1135                                 /*
1136                                  * We are done for this pass.
1137                                  */
1138                                 break;
1139                         }
1140
1141                 } else if (ret == -ENOBUFS) {
1142                         if (bufferlen > NETVSC_PACKET_SIZE)
1143                                 kfree(buffer);
1144                         /* Handle large packet */
1145                         buffer = kmalloc(bytes_recvd, GFP_ATOMIC);
1146                         if (buffer == NULL) {
1147                                 /* Try again next time around */
1148                                 netdev_err(ndev,
1149                                            "unable to allocate buffer of size "
1150                                            "(%d)!!\n", bytes_recvd);
1151                                 break;
1152                         }
1153
1154                         bufferlen = bytes_recvd;
1155                 }
1156         } while (1);
1157
1158         if (bufferlen > NETVSC_PACKET_SIZE)
1159                 kfree(buffer);
1160         return;
1161 }
1162
1163 /*
1164  * netvsc_device_add - Callback when the device belonging to this
1165  * driver is added
1166  */
1167 int netvsc_device_add(struct hv_device *device, void *additional_info)
1168 {
1169         int ret = 0;
1170         int ring_size =
1171         ((struct netvsc_device_info *)additional_info)->ring_size;
1172         struct netvsc_device *net_device;
1173         struct net_device *ndev;
1174
1175         net_device = alloc_net_device(device);
1176         if (!net_device)
1177                 return -ENOMEM;
1178
1179         net_device->ring_size = ring_size;
1180
1181         /*
1182          * Coming into this function, struct net_device * is
1183          * registered as the driver private data.
1184          * In alloc_net_device(), we register struct netvsc_device *
1185          * as the driver private data and stash away struct net_device *
1186          * in struct netvsc_device *.
1187          */
1188         ndev = net_device->ndev;
1189
1190         /* Add netvsc_device context to netvsc_device */
1191         net_device->nd_ctx = netdev_priv(ndev);
1192
1193         /* Initialize the NetVSC channel extension */
1194         init_completion(&net_device->channel_init_wait);
1195
1196         set_per_channel_state(device->channel, net_device->cb_buffer);
1197
1198         /* Open the channel */
1199         ret = vmbus_open(device->channel, ring_size * PAGE_SIZE,
1200                          ring_size * PAGE_SIZE, NULL, 0,
1201                          netvsc_channel_cb, device->channel);
1202
1203         if (ret != 0) {
1204                 netdev_err(ndev, "unable to open channel: %d\n", ret);
1205                 goto cleanup;
1206         }
1207
1208         /* Channel is opened */
1209         pr_info("hv_netvsc channel opened successfully\n");
1210
1211         net_device->chn_table[0] = device->channel;
1212
1213         /* Connect with the NetVsp */
1214         ret = netvsc_connect_vsp(device);
1215         if (ret != 0) {
1216                 netdev_err(ndev,
1217                         "unable to connect to NetVSP - %d\n", ret);
1218                 goto close;
1219         }
1220
1221         return ret;
1222
1223 close:
1224         /* Now, we can close the channel safely */
1225         vmbus_close(device->channel);
1226
1227 cleanup:
1228         free_netvsc_device(net_device);
1229
1230         return ret;
1231 }