sys/dev/hyperv/vmbus/hv_channel.c

   1 /*-
   2  * Copyright (c) 2009-2012 Microsoft Corp.
   3  * Copyright (c) 2012 NetApp Inc.
   4  * Copyright (c) 2012 Citrix Inc.
   5  * All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice unmodified, this list of conditions, and the following
  12  *    disclaimer.
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in the
  15  *    documentation and/or other materials provided with the distribution.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  18  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  19  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  20  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  21  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  22  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  23  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  24  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  26  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  27  */
  28
  29 #include <sys/cdefs.h>
  30 __FBSDID("$FreeBSD$");
  31
  32 #include <sys/param.h>
  33 #include <sys/malloc.h>
  34 #include <sys/systm.h>
  35 #include <sys/mbuf.h>
  36 #include <sys/lock.h>
  37 #include <sys/mutex.h>
  38 #include <machine/bus.h>
  39 #include <vm/vm.h>
  40 #include <vm/vm_param.h>
  41 #include <vm/pmap.h>
  42
  43 #include "hv_vmbus_priv.h"
  44
  45 static int      vmbus_channel_create_gpadl_header(
  46                         /* must be phys and virt contiguous*/
  47                         void*                           contig_buffer,
  48                         /* page-size multiple */
  49                         uint32_t                        size,
  50                         hv_vmbus_channel_msg_info**     msg_info,
  51                         uint32_t*                       message_count);
  52
  53 static void     vmbus_channel_set_event(hv_vmbus_channel* channel);
  54 static void     VmbusProcessChannelEvent(void* channel, int pending);
  55
  56 /**
  57  *  @brief Trigger an event notification on the specified channel
  58  */
  59 static void
  60 vmbus_channel_set_event(hv_vmbus_channel *channel)
  61 {
  62         hv_vmbus_monitor_page *monitor_page;
  63
  64         if (channel->offer_msg.monitor_allocated) {
  65                 /* Each uint32_t represents 32 channels */
  66                 synch_set_bit((channel->offer_msg.child_rel_id & 31),
  67                         ((uint32_t *)hv_vmbus_g_connection.send_interrupt_page
  68                                 + ((channel->offer_msg.child_rel_id >> 5))));
  69
  70                 monitor_page = (hv_vmbus_monitor_page *)
  71                         hv_vmbus_g_connection.monitor_page_2;
  72
  73                 synch_set_bit(channel->monitor_bit,
  74                         (uint32_t *)&monitor_page->
  75                                 trigger_group[channel->monitor_group].u.pending);
  76         } else {
  77                 hv_vmbus_set_event(channel);
  78         }
  79
  80 }
  81
  82 /**
  83  * @brief Open the specified channel
  84  */
  85 int
  86 hv_vmbus_channel_open(
  87         hv_vmbus_channel*               new_channel,
  88         uint32_t                        send_ring_buffer_size,
  89         uint32_t                        recv_ring_buffer_size,
  90         void*                           user_data,
  91         uint32_t                        user_data_len,
  92         hv_vmbus_pfn_channel_callback   pfn_on_channel_callback,
  93         void*                           context)
  94 {
  95
  96         int ret = 0;
  97         void *in, *out;
  98         hv_vmbus_channel_open_channel*  open_msg;
  99         hv_vmbus_channel_msg_info*      open_info;
 100
 101         mtx_lock(&new_channel->sc_lock);
 102         if (new_channel->state == HV_CHANNEL_OPEN_STATE) {
 103             new_channel->state = HV_CHANNEL_OPENING_STATE;
 104         } else {
 105             mtx_unlock(&new_channel->sc_lock);
 106             if(bootverbose)
 107                 printf("VMBUS: Trying to open channel <%p> which in "
 108                     "%d state.\n", new_channel, new_channel->state);
 109             return (EINVAL);
 110         }
 111         mtx_unlock(&new_channel->sc_lock);
 112
 113         new_channel->on_channel_callback = pfn_on_channel_callback;
 114         new_channel->channel_callback_context = context;
 115
 116         new_channel->rxq = hv_vmbus_g_context.hv_event_queue[new_channel->target_cpu];
 117         TASK_INIT(&new_channel->channel_task, 0, VmbusProcessChannelEvent, new_channel);
 118
 119         /* Allocate the ring buffer */
 120         out = contigmalloc((send_ring_buffer_size + recv_ring_buffer_size),
 121             M_DEVBUF, M_ZERO, 0UL, BUS_SPACE_MAXADDR, PAGE_SIZE, 0);
 122         KASSERT(out != NULL,
 123             ("Error VMBUS: contigmalloc failed to allocate Ring Buffer!"));
 124         if (out == NULL)
 125                 return (ENOMEM);
 126
 127         in = ((uint8_t *) out + send_ring_buffer_size);
 128
 129         new_channel->ring_buffer_pages = out;
 130         new_channel->ring_buffer_page_count = (send_ring_buffer_size +
 131             recv_ring_buffer_size) >> PAGE_SHIFT;
 132         new_channel->ring_buffer_size = send_ring_buffer_size +
 133             recv_ring_buffer_size;
 134
 135         hv_vmbus_ring_buffer_init(
 136                 &new_channel->outbound,
 137                 out,
 138                 send_ring_buffer_size);
 139
 140         hv_vmbus_ring_buffer_init(
 141                 &new_channel->inbound,
 142                 in,
 143                 recv_ring_buffer_size);
 144
 145         /**
 146          * Establish the gpadl for the ring buffer
 147          */
 148         new_channel->ring_buffer_gpadl_handle = 0;
 149
 150         ret = hv_vmbus_channel_establish_gpadl(new_channel,
 151                 new_channel->outbound.ring_buffer,
 152                 send_ring_buffer_size + recv_ring_buffer_size,
 153                 &new_channel->ring_buffer_gpadl_handle);
 154
 155         /**
 156          * Create and init the channel open message
 157          */
 158         open_info = (hv_vmbus_channel_msg_info*) malloc(
 159                 sizeof(hv_vmbus_channel_msg_info) +
 160                         sizeof(hv_vmbus_channel_open_channel),
 161                 M_DEVBUF,
 162                 M_NOWAIT);
 163         KASSERT(open_info != NULL,
 164             ("Error VMBUS: malloc failed to allocate Open Channel message!"));
 165
 166         if (open_info == NULL)
 167                 return (ENOMEM);
 168
 169         sema_init(&open_info->wait_sema, 0, "Open Info Sema");
 170
 171         open_msg = (hv_vmbus_channel_open_channel*) open_info->msg;
 172         open_msg->header.message_type = HV_CHANNEL_MESSAGE_OPEN_CHANNEL;
 173         open_msg->open_id = new_channel->offer_msg.child_rel_id;
 174         open_msg->child_rel_id = new_channel->offer_msg.child_rel_id;
 175         open_msg->ring_buffer_gpadl_handle =
 176                 new_channel->ring_buffer_gpadl_handle;
 177         open_msg->downstream_ring_buffer_page_offset = send_ring_buffer_size
 178                 >> PAGE_SHIFT;
 179         open_msg->target_vcpu = new_channel->target_vcpu;
 180
 181         if (user_data_len)
 182                 memcpy(open_msg->user_data, user_data, user_data_len);
 183
 184         mtx_lock_spin(&hv_vmbus_g_connection.channel_msg_lock);
 185         TAILQ_INSERT_TAIL(
 186                 &hv_vmbus_g_connection.channel_msg_anchor,
 187                 open_info,
 188                 msg_list_entry);
 189         mtx_unlock_spin(&hv_vmbus_g_connection.channel_msg_lock);
 190
 191         ret = hv_vmbus_post_message(
 192                 open_msg, sizeof(hv_vmbus_channel_open_channel));
 193
 194         if (ret != 0)
 195             goto cleanup;
 196
 197         ret = sema_timedwait(&open_info->wait_sema, 500); /* KYS 5 seconds */
 198
 199         if (ret) {
 200             if(bootverbose)
 201                 printf("VMBUS: channel <%p> open timeout.\n", new_channel);
 202             goto cleanup;
 203         }
 204
 205         if (open_info->response.open_result.status == 0) {
 206             new_channel->state = HV_CHANNEL_OPENED_STATE;
 207             if(bootverbose)
 208                 printf("VMBUS: channel <%p> open success.\n", new_channel);
 209         } else {
 210             if(bootverbose)
 211                 printf("Error VMBUS: channel <%p> open failed - %d!\n",
 212                         new_channel, open_info->response.open_result.status);
 213         }
 214
 215         cleanup:
 216         mtx_lock_spin(&hv_vmbus_g_connection.channel_msg_lock);
 217         TAILQ_REMOVE(
 218                 &hv_vmbus_g_connection.channel_msg_anchor,
 219                 open_info,
 220                 msg_list_entry);
 221         mtx_unlock_spin(&hv_vmbus_g_connection.channel_msg_lock);
 222         sema_destroy(&open_info->wait_sema);
 223         free(open_info, M_DEVBUF);
 224
 225         return (ret);
 226 }
 227
 228 /**
 229  * @brief Create a gpadl for the specified buffer
 230  */
 231 static int
 232 vmbus_channel_create_gpadl_header(
 233         void*                           contig_buffer,
 234         uint32_t                        size,   /* page-size multiple */
 235         hv_vmbus_channel_msg_info**     msg_info,
 236         uint32_t*                       message_count)
 237 {
 238         int                             i;
 239         int                             page_count;
 240         unsigned long long              pfn;
 241         uint32_t                        msg_size;
 242         hv_vmbus_channel_gpadl_header*  gpa_header;
 243         hv_vmbus_channel_gpadl_body*    gpadl_body;
 244         hv_vmbus_channel_msg_info*      msg_header;
 245         hv_vmbus_channel_msg_info*      msg_body;
 246
 247         int pfnSum, pfnCount, pfnLeft, pfnCurr, pfnSize;
 248
 249         page_count = size >> PAGE_SHIFT;
 250         pfn = hv_get_phys_addr(contig_buffer) >> PAGE_SHIFT;
 251
 252         /*do we need a gpadl body msg */
 253         pfnSize = HV_MAX_SIZE_CHANNEL_MESSAGE
 254             - sizeof(hv_vmbus_channel_gpadl_header)
 255             - sizeof(hv_gpa_range);
 256         pfnCount = pfnSize / sizeof(uint64_t);
 257
 258         if (page_count > pfnCount) { /* if(we need a gpadl body)        */
 259             /* fill in the header               */
 260             msg_size = sizeof(hv_vmbus_channel_msg_info)
 261                 + sizeof(hv_vmbus_channel_gpadl_header)
 262                 + sizeof(hv_gpa_range)
 263                 + pfnCount * sizeof(uint64_t);
 264             msg_header = malloc(msg_size, M_DEVBUF, M_NOWAIT | M_ZERO);
 265             KASSERT(
 266                 msg_header != NULL,
 267                 ("Error VMBUS: malloc failed to allocate Gpadl Message!"));
 268             if (msg_header == NULL)
 269                 return (ENOMEM);
 270
 271             TAILQ_INIT(&msg_header->sub_msg_list_anchor);
 272             msg_header->message_size = msg_size;
 273
 274             gpa_header = (hv_vmbus_channel_gpadl_header*) msg_header->msg;
 275             gpa_header->range_count = 1;
 276             gpa_header->range_buf_len = sizeof(hv_gpa_range)
 277                 + page_count * sizeof(uint64_t);
 278             gpa_header->range[0].byte_offset = 0;
 279             gpa_header->range[0].byte_count = size;
 280             for (i = 0; i < pfnCount; i++) {
 281                 gpa_header->range[0].pfn_array[i] = pfn + i;
 282             }
 283             *msg_info = msg_header;
 284             *message_count = 1;
 285
 286             pfnSum = pfnCount;
 287             pfnLeft = page_count - pfnCount;
 288
 289             /*
 290              *  figure out how many pfns we can fit
 291              */
 292             pfnSize = HV_MAX_SIZE_CHANNEL_MESSAGE
 293                 - sizeof(hv_vmbus_channel_gpadl_body);
 294             pfnCount = pfnSize / sizeof(uint64_t);
 295
 296             /*
 297              * fill in the body
 298              */
 299             while (pfnLeft) {
 300                 if (pfnLeft > pfnCount) {
 301                     pfnCurr = pfnCount;
 302                 } else {
 303                     pfnCurr = pfnLeft;
 304                 }
 305
 306                 msg_size = sizeof(hv_vmbus_channel_msg_info) +
 307                     sizeof(hv_vmbus_channel_gpadl_body) +
 308                     pfnCurr * sizeof(uint64_t);
 309                 msg_body = malloc(msg_size, M_DEVBUF, M_NOWAIT | M_ZERO);
 310                 KASSERT(
 311                     msg_body != NULL,
 312                     ("Error VMBUS: malloc failed to allocate Gpadl msg_body!"));
 313                 if (msg_body == NULL)
 314                     return (ENOMEM);
 315
 316                 msg_body->message_size = msg_size;
 317                 (*message_count)++;
 318                 gpadl_body =
 319                     (hv_vmbus_channel_gpadl_body*) msg_body->msg;
 320                 /*
 321                  * gpadl_body->gpadl = kbuffer;
 322                  */
 323                 for (i = 0; i < pfnCurr; i++) {
 324                     gpadl_body->pfn[i] = pfn + pfnSum + i;
 325                 }
 326
 327                 TAILQ_INSERT_TAIL(
 328                     &msg_header->sub_msg_list_anchor,
 329                     msg_body,
 330                     msg_list_entry);
 331                 pfnSum += pfnCurr;
 332                 pfnLeft -= pfnCurr;
 333             }
 334         } else { /* else everything fits in a header */
 335
 336             msg_size = sizeof(hv_vmbus_channel_msg_info) +
 337                 sizeof(hv_vmbus_channel_gpadl_header) +
 338                 sizeof(hv_gpa_range) +
 339                 page_count * sizeof(uint64_t);
 340             msg_header = malloc(msg_size, M_DEVBUF, M_NOWAIT | M_ZERO);
 341             KASSERT(
 342                 msg_header != NULL,
 343                 ("Error VMBUS: malloc failed to allocate Gpadl Message!"));
 344             if (msg_header == NULL)
 345                 return (ENOMEM);
 346
 347             msg_header->message_size = msg_size;
 348
 349             gpa_header = (hv_vmbus_channel_gpadl_header*) msg_header->msg;
 350             gpa_header->range_count = 1;
 351             gpa_header->range_buf_len = sizeof(hv_gpa_range) +
 352                 page_count * sizeof(uint64_t);
 353             gpa_header->range[0].byte_offset = 0;
 354             gpa_header->range[0].byte_count = size;
 355             for (i = 0; i < page_count; i++) {
 356                 gpa_header->range[0].pfn_array[i] = pfn + i;
 357             }
 358
 359             *msg_info = msg_header;
 360             *message_count = 1;
 361         }
 362
 363         return (0);
 364 }
 365
 366 /**
 367  * @brief Establish a GPADL for the specified buffer
 368  */
 369 int
 370 hv_vmbus_channel_establish_gpadl(
 371         hv_vmbus_channel*       channel,
 372         void*                   contig_buffer,
 373         uint32_t                size, /* page-size multiple */
 374         uint32_t*               gpadl_handle)
 375
 376 {
 377         int ret = 0;
 378         hv_vmbus_channel_gpadl_header*  gpadl_msg;
 379         hv_vmbus_channel_gpadl_body*    gpadl_body;
 380         hv_vmbus_channel_msg_info*      msg_info;
 381         hv_vmbus_channel_msg_info*      sub_msg_info;
 382         uint32_t                        msg_count;
 383         hv_vmbus_channel_msg_info*      curr;
 384         uint32_t                        next_gpadl_handle;
 385
 386         next_gpadl_handle = hv_vmbus_g_connection.next_gpadl_handle;
 387         atomic_add_int((int*) &hv_vmbus_g_connection.next_gpadl_handle, 1);
 388
 389         ret = vmbus_channel_create_gpadl_header(
 390                 contig_buffer, size, &msg_info, &msg_count);
 391
 392         if(ret != 0) { /* if(allocation failed) return immediately */
 393             /* reverse atomic_add_int above */
 394             atomic_subtract_int((int*)
 395                     &hv_vmbus_g_connection.next_gpadl_handle, 1);
 396             return ret;
 397         }
 398
 399         sema_init(&msg_info->wait_sema, 0, "Open Info Sema");
 400         gpadl_msg = (hv_vmbus_channel_gpadl_header*) msg_info->msg;
 401         gpadl_msg->header.message_type = HV_CHANNEL_MESSAGEL_GPADL_HEADER;
 402         gpadl_msg->child_rel_id = channel->offer_msg.child_rel_id;
 403         gpadl_msg->gpadl = next_gpadl_handle;
 404
 405         mtx_lock_spin(&hv_vmbus_g_connection.channel_msg_lock);
 406         TAILQ_INSERT_TAIL(
 407                 &hv_vmbus_g_connection.channel_msg_anchor,
 408                 msg_info,
 409                 msg_list_entry);
 410
 411         mtx_unlock_spin(&hv_vmbus_g_connection.channel_msg_lock);
 412
 413         ret = hv_vmbus_post_message(
 414                 gpadl_msg,
 415                 msg_info->message_size -
 416                     (uint32_t) sizeof(hv_vmbus_channel_msg_info));
 417
 418         if (ret != 0)
 419             goto cleanup;
 420
 421         if (msg_count > 1) {
 422             TAILQ_FOREACH(curr,
 423                     &msg_info->sub_msg_list_anchor, msg_list_entry) {
 424                 sub_msg_info = curr;
 425                 gpadl_body =
 426                     (hv_vmbus_channel_gpadl_body*) sub_msg_info->msg;
 427
 428                 gpadl_body->header.message_type =
 429                     HV_CHANNEL_MESSAGE_GPADL_BODY;
 430                 gpadl_body->gpadl = next_gpadl_handle;
 431
 432                 ret = hv_vmbus_post_message(
 433                         gpadl_body,
 434                         sub_msg_info->message_size
 435                             - (uint32_t) sizeof(hv_vmbus_channel_msg_info));
 436                  /* if (the post message failed) give up and clean up */
 437                 if(ret != 0)
 438                     goto cleanup;
 439             }
 440         }
 441
 442         ret = sema_timedwait(&msg_info->wait_sema, 500); /* KYS 5 seconds*/
 443         if (ret != 0)
 444             goto cleanup;
 445
 446         *gpadl_handle = gpadl_msg->gpadl;
 447
 448 cleanup:
 449
 450         mtx_lock_spin(&hv_vmbus_g_connection.channel_msg_lock);
 451         TAILQ_REMOVE(&hv_vmbus_g_connection.channel_msg_anchor,
 452                 msg_info, msg_list_entry);
 453         mtx_unlock_spin(&hv_vmbus_g_connection.channel_msg_lock);
 454
 455         sema_destroy(&msg_info->wait_sema);
 456         free(msg_info, M_DEVBUF);
 457
 458         return (ret);
 459 }
 460
 461 /**
 462  * @brief Teardown the specified GPADL handle
 463  */
 464 int
 465 hv_vmbus_channel_teardown_gpdal(
 466         hv_vmbus_channel*       channel,
 467         uint32_t                gpadl_handle)
 468 {
 469         int                                     ret = 0;
 470         hv_vmbus_channel_gpadl_teardown*        msg;
 471         hv_vmbus_channel_msg_info*              info;
 472
 473         info = (hv_vmbus_channel_msg_info *)
 474                 malloc( sizeof(hv_vmbus_channel_msg_info) +
 475                         sizeof(hv_vmbus_channel_gpadl_teardown),
 476                                 M_DEVBUF, M_NOWAIT);
 477         KASSERT(info != NULL,
 478             ("Error VMBUS: malloc failed to allocate Gpadl Teardown Msg!"));
 479         if (info == NULL) {
 480             ret = ENOMEM;
 481             goto cleanup;
 482         }
 483
 484         sema_init(&info->wait_sema, 0, "Open Info Sema");
 485
 486         msg = (hv_vmbus_channel_gpadl_teardown*) info->msg;
 487
 488         msg->header.message_type = HV_CHANNEL_MESSAGE_GPADL_TEARDOWN;
 489         msg->child_rel_id = channel->offer_msg.child_rel_id;
 490         msg->gpadl = gpadl_handle;
 491
 492         mtx_lock_spin(&hv_vmbus_g_connection.channel_msg_lock);
 493         TAILQ_INSERT_TAIL(&hv_vmbus_g_connection.channel_msg_anchor,
 494                         info, msg_list_entry);
 495         mtx_unlock_spin(&hv_vmbus_g_connection.channel_msg_lock);
 496
 497         ret = hv_vmbus_post_message(msg,
 498                         sizeof(hv_vmbus_channel_gpadl_teardown));
 499         if (ret != 0)
 500             goto cleanup;
 501
 502         ret = sema_timedwait(&info->wait_sema, 500); /* KYS 5 seconds */
 503
 504 cleanup:
 505         /*
 506          * Received a torndown response
 507          */
 508         mtx_lock_spin(&hv_vmbus_g_connection.channel_msg_lock);
 509         TAILQ_REMOVE(&hv_vmbus_g_connection.channel_msg_anchor,
 510                         info, msg_list_entry);
 511         mtx_unlock_spin(&hv_vmbus_g_connection.channel_msg_lock);
 512         sema_destroy(&info->wait_sema);
 513         free(info, M_DEVBUF);
 514
 515         return (ret);
 516 }
 517
 518 static void
 519 hv_vmbus_channel_close_internal(hv_vmbus_channel *channel)
 520 {
 521         int ret = 0;
 522         struct taskqueue *rxq = channel->rxq;
 523         hv_vmbus_channel_close_channel* msg;
 524         hv_vmbus_channel_msg_info* info;
 525
 526         channel->state = HV_CHANNEL_OPEN_STATE;
 527         channel->sc_creation_callback = NULL;
 528
 529         /*
 530          * set rxq to NULL to avoid more requests be scheduled
 531          */
 532         channel->rxq = NULL;
 533         taskqueue_drain(rxq, &channel->channel_task);
 534         /*
 535          * Grab the lock to prevent race condition when a packet received
 536          * and unloading driver is in the process.
 537          */
 538         mtx_lock(&channel->inbound_lock);
 539         channel->on_channel_callback = NULL;
 540         mtx_unlock(&channel->inbound_lock);
 541
 542         /**
 543          * Send a closing message
 544          */
 545         info = (hv_vmbus_channel_msg_info *)
 546                 malloc( sizeof(hv_vmbus_channel_msg_info) +
 547                         sizeof(hv_vmbus_channel_close_channel),
 548                                 M_DEVBUF, M_NOWAIT);
 549         KASSERT(info != NULL, ("VMBUS: malloc failed hv_vmbus_channel_close!"));
 550         if(info == NULL)
 551             return;
 552
 553         msg = (hv_vmbus_channel_close_channel*) info->msg;
 554         msg->header.message_type = HV_CHANNEL_MESSAGE_CLOSE_CHANNEL;
 555         msg->child_rel_id = channel->offer_msg.child_rel_id;
 556
 557         ret = hv_vmbus_post_message(
 558                 msg, sizeof(hv_vmbus_channel_close_channel));
 559
 560         /* Tear down the gpadl for the channel's ring buffer */
 561         if (channel->ring_buffer_gpadl_handle) {
 562                 hv_vmbus_channel_teardown_gpdal(channel,
 563                         channel->ring_buffer_gpadl_handle);
 564         }
 565
 566         /* TODO: Send a msg to release the childRelId */
 567
 568         /* cleanup the ring buffers for this channel */
 569         hv_ring_buffer_cleanup(&channel->outbound);
 570         hv_ring_buffer_cleanup(&channel->inbound);
 571
 572         contigfree(channel->ring_buffer_pages, channel->ring_buffer_size,
 573             M_DEVBUF);
 574
 575         free(info, M_DEVBUF);
 576 }
 577
 578 /**
 579  * @brief Close the specified channel
 580  */
 581 void
 582 hv_vmbus_channel_close(hv_vmbus_channel *channel)
 583 {
 584         hv_vmbus_channel*       sub_channel;
 585
 586         if (channel->primary_channel != NULL) {
 587                 /*
 588                  * We only close multi-channels when the primary is
 589                  * closed.
 590                  */
 591                 return;
 592         }
 593
 594         /*
 595          * Close all multi-channels first.
 596          */
 597         TAILQ_FOREACH(sub_channel, &channel->sc_list_anchor,
 598             sc_list_entry) {
 599                 if (sub_channel->state != HV_CHANNEL_OPENED_STATE)
 600                         continue;
 601                 hv_vmbus_channel_close_internal(sub_channel);
 602         }
 603         /*
 604          * Then close the primary channel.
 605          */
 606         hv_vmbus_channel_close_internal(channel);
 607 }
 608
 609 /**
 610  * @brief Send the specified buffer on the given channel
 611  */
 612 int
 613 hv_vmbus_channel_send_packet(
 614         hv_vmbus_channel*       channel,
 615         void*                   buffer,
 616         uint32_t                buffer_len,
 617         uint64_t                request_id,
 618         hv_vmbus_packet_type    type,
 619         uint32_t                flags)
 620 {
 621         int                     ret = 0;
 622         hv_vm_packet_descriptor desc;
 623         uint32_t                packet_len;
 624         uint64_t                aligned_data;
 625         uint32_t                packet_len_aligned;
 626         boolean_t               need_sig;
 627         hv_vmbus_sg_buffer_list buffer_list[3];
 628
 629         packet_len = sizeof(hv_vm_packet_descriptor) + buffer_len;
 630         packet_len_aligned = HV_ALIGN_UP(packet_len, sizeof(uint64_t));
 631         aligned_data = 0;
 632
 633         /* Setup the descriptor */
 634         desc.type = type;   /* HV_VMBUS_PACKET_TYPE_DATA_IN_BAND;             */
 635         desc.flags = flags; /* HV_VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED */
 636                             /* in 8-bytes granularity */
 637         desc.data_offset8 = sizeof(hv_vm_packet_descriptor) >> 3;
 638         desc.length8 = (uint16_t) (packet_len_aligned >> 3);
 639         desc.transaction_id = request_id;
 640
 641         buffer_list[0].data = &desc;
 642         buffer_list[0].length = sizeof(hv_vm_packet_descriptor);
 643
 644         buffer_list[1].data = buffer;
 645         buffer_list[1].length = buffer_len;
 646
 647         buffer_list[2].data = &aligned_data;
 648         buffer_list[2].length = packet_len_aligned - packet_len;
 649
 650         ret = hv_ring_buffer_write(&channel->outbound, buffer_list, 3,
 651             &need_sig);
 652
 653         /* TODO: We should determine if this is optional */
 654         if (ret == 0 && need_sig) {
 655                 vmbus_channel_set_event(channel);
 656         }
 657
 658         return (ret);
 659 }
 660
 661 /**
 662  * @brief Send a range of single-page buffer packets using
 663  * a GPADL Direct packet type
 664  */
 665 int
 666 hv_vmbus_channel_send_packet_pagebuffer(
 667         hv_vmbus_channel*       channel,
 668         hv_vmbus_page_buffer    page_buffers[],
 669         uint32_t                page_count,
 670         void*                   buffer,
 671         uint32_t                buffer_len,
 672         uint64_t                request_id)
 673 {
 674
 675         int                                     ret = 0;
 676         boolean_t                               need_sig;
 677         uint32_t                                packet_len;
 678         uint32_t                                page_buflen;
 679         uint32_t                                packetLen_aligned;
 680         hv_vmbus_sg_buffer_list                 buffer_list[4];
 681         hv_vmbus_channel_packet_page_buffer     desc;
 682         uint32_t                                descSize;
 683         uint64_t                                alignedData = 0;
 684
 685         if (page_count > HV_MAX_PAGE_BUFFER_COUNT)
 686                 return (EINVAL);
 687
 688         /*
 689          * Adjust the size down since hv_vmbus_channel_packet_page_buffer
 690          *  is the largest size we support
 691          */
 692         descSize = __offsetof(hv_vmbus_channel_packet_page_buffer, range);
 693         page_buflen = sizeof(hv_vmbus_page_buffer) * page_count;
 694         packet_len = descSize + page_buflen + buffer_len;
 695         packetLen_aligned = HV_ALIGN_UP(packet_len, sizeof(uint64_t));
 696
 697         /* Setup the descriptor */
 698         desc.type = HV_VMBUS_PACKET_TYPE_DATA_USING_GPA_DIRECT;
 699         desc.flags = HV_VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED;
 700         /* in 8-bytes granularity */
 701         desc.data_offset8 = (descSize + page_buflen) >> 3;
 702         desc.length8 = (uint16_t) (packetLen_aligned >> 3);
 703         desc.transaction_id = request_id;
 704         desc.range_count = page_count;
 705
 706         buffer_list[0].data = &desc;
 707         buffer_list[0].length = descSize;
 708
 709         buffer_list[1].data = page_buffers;
 710         buffer_list[1].length = page_buflen;
 711
 712         buffer_list[2].data = buffer;
 713         buffer_list[2].length = buffer_len;
 714
 715         buffer_list[3].data = &alignedData;
 716         buffer_list[3].length = packetLen_aligned - packet_len;
 717
 718         ret = hv_ring_buffer_write(&channel->outbound, buffer_list, 4,
 719             &need_sig);
 720
 721         /* TODO: We should determine if this is optional */
 722         if (ret == 0 && need_sig) {
 723                 vmbus_channel_set_event(channel);
 724         }
 725
 726         return (ret);
 727 }
 728
 729 /**
 730  * @brief Send a multi-page buffer packet using a GPADL Direct packet type
 731  */
 732 int
 733 hv_vmbus_channel_send_packet_multipagebuffer(
 734         hv_vmbus_channel*               channel,
 735         hv_vmbus_multipage_buffer*      multi_page_buffer,
 736         void*                           buffer,
 737         uint32_t                        buffer_len,
 738         uint64_t                        request_id)
 739 {
 740
 741         int                     ret = 0;
 742         uint32_t                desc_size;
 743         boolean_t               need_sig;
 744         uint32_t                packet_len;
 745         uint32_t                packet_len_aligned;
 746         uint32_t                pfn_count;
 747         uint64_t                aligned_data = 0;
 748         hv_vmbus_sg_buffer_list buffer_list[3];
 749         hv_vmbus_channel_packet_multipage_buffer desc;
 750
 751         pfn_count =
 752             HV_NUM_PAGES_SPANNED(
 753                     multi_page_buffer->offset,
 754                     multi_page_buffer->length);
 755
 756         if ((pfn_count == 0) || (pfn_count > HV_MAX_MULTIPAGE_BUFFER_COUNT))
 757             return (EINVAL);
 758         /*
 759          * Adjust the size down since hv_vmbus_channel_packet_multipage_buffer
 760          * is the largest size we support
 761          */
 762         desc_size =
 763             sizeof(hv_vmbus_channel_packet_multipage_buffer) -
 764                     ((HV_MAX_MULTIPAGE_BUFFER_COUNT - pfn_count) *
 765                         sizeof(uint64_t));
 766         packet_len = desc_size + buffer_len;
 767         packet_len_aligned = HV_ALIGN_UP(packet_len, sizeof(uint64_t));
 768
 769         /*
 770          * Setup the descriptor
 771          */
 772         desc.type = HV_VMBUS_PACKET_TYPE_DATA_USING_GPA_DIRECT;
 773         desc.flags = HV_VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED;
 774         desc.data_offset8 = desc_size >> 3; /* in 8-bytes granularity */
 775         desc.length8 = (uint16_t) (packet_len_aligned >> 3);
 776         desc.transaction_id = request_id;
 777         desc.range_count = 1;
 778
 779         desc.range.length = multi_page_buffer->length;
 780         desc.range.offset = multi_page_buffer->offset;
 781
 782         memcpy(desc.range.pfn_array, multi_page_buffer->pfn_array,
 783                 pfn_count * sizeof(uint64_t));
 784
 785         buffer_list[0].data = &desc;
 786         buffer_list[0].length = desc_size;
 787
 788         buffer_list[1].data = buffer;
 789         buffer_list[1].length = buffer_len;
 790
 791         buffer_list[2].data = &aligned_data;
 792         buffer_list[2].length = packet_len_aligned - packet_len;
 793
 794         ret = hv_ring_buffer_write(&channel->outbound, buffer_list, 3,
 795             &need_sig);
 796
 797         /* TODO: We should determine if this is optional */
 798         if (ret == 0 && need_sig) {
 799             vmbus_channel_set_event(channel);
 800         }
 801
 802         return (ret);
 803 }
 804
 805 /**
 806  * @brief Retrieve the user packet on the specified channel
 807  */
 808 int
 809 hv_vmbus_channel_recv_packet(
 810         hv_vmbus_channel*       channel,
 811         void*                   Buffer,
 812         uint32_t                buffer_len,
 813         uint32_t*               buffer_actual_len,
 814         uint64_t*               request_id)
 815 {
 816         int                     ret;
 817         uint32_t                user_len;
 818         uint32_t                packet_len;
 819         hv_vm_packet_descriptor desc;
 820
 821         *buffer_actual_len = 0;
 822         *request_id = 0;
 823
 824         ret = hv_ring_buffer_peek(&channel->inbound, &desc,
 825                 sizeof(hv_vm_packet_descriptor));
 826         if (ret != 0)
 827                 return (0);
 828
 829         packet_len = desc.length8 << 3;
 830         user_len = packet_len - (desc.data_offset8 << 3);
 831
 832         *buffer_actual_len = user_len;
 833
 834         if (user_len > buffer_len)
 835                 return (EINVAL);
 836
 837         *request_id = desc.transaction_id;
 838
 839         /* Copy over the packet to the user buffer */
 840         ret = hv_ring_buffer_read(&channel->inbound, Buffer, user_len,
 841                 (desc.data_offset8 << 3));
 842
 843         return (0);
 844 }
 845
 846 /**
 847  * @brief Retrieve the raw packet on the specified channel
 848  */
 849 int
 850 hv_vmbus_channel_recv_packet_raw(
 851         hv_vmbus_channel*       channel,
 852         void*                   buffer,
 853         uint32_t                buffer_len,
 854         uint32_t*               buffer_actual_len,
 855         uint64_t*               request_id)
 856 {
 857         int             ret;
 858         uint32_t        packetLen;
 859         uint32_t        userLen;
 860         hv_vm_packet_descriptor desc;
 861
 862         *buffer_actual_len = 0;
 863         *request_id = 0;
 864
 865         ret = hv_ring_buffer_peek(
 866                 &channel->inbound, &desc,
 867                 sizeof(hv_vm_packet_descriptor));
 868
 869         if (ret != 0)
 870             return (0);
 871
 872         packetLen = desc.length8 << 3;
 873         userLen = packetLen - (desc.data_offset8 << 3);
 874
 875         *buffer_actual_len = packetLen;
 876
 877         if (packetLen > buffer_len)
 878             return (ENOBUFS);
 879
 880         *request_id = desc.transaction_id;
 881
 882         /* Copy over the entire packet to the user buffer */
 883         ret = hv_ring_buffer_read(&channel->inbound, buffer, packetLen, 0);
 884
 885         return (0);
 886 }
 887
 888
 889 /**
 890  * Process a channel event notification
 891  */
 892 static void
 893 VmbusProcessChannelEvent(void* context, int pending)
 894 {
 895         void* arg;
 896         uint32_t bytes_to_read;
 897         hv_vmbus_channel* channel = (hv_vmbus_channel*)context;
 898         boolean_t is_batched_reading;
 899
 900         /**
 901          * Find the channel based on this relid and invokes
 902          * the channel callback to process the event
 903          */
 904
 905         if (channel == NULL) {
 906                 return;
 907         }
 908         /**
 909          * To deal with the race condition where we might
 910          * receive a packet while the relevant driver is
 911          * being unloaded, dispatch the callback while
 912          * holding the channel lock. The unloading driver
 913          * will acquire the same channel lock to set the
 914          * callback to NULL. This closes the window.
 915          */
 916
 917         /*
 918          * Disable the lock due to newly added WITNESS check in r277723.
 919          * Will seek other way to avoid race condition.
 920          * -- whu
 921          */
 922         // mtx_lock(&channel->inbound_lock);
 923         if (channel->on_channel_callback != NULL) {
 924                 arg = channel->channel_callback_context;
 925                 is_batched_reading = channel->batched_reading;
 926                 /*
 927                  * Optimize host to guest signaling by ensuring:
 928                  * 1. While reading the channel, we disable interrupts from
 929                  *    host.
 930                  * 2. Ensure that we process all posted messages from the host
 931                  *    before returning from this callback.
 932                  * 3. Once we return, enable signaling from the host. Once this
 933                  *    state is set we check to see if additional packets are
 934                  *    available to read. In this case we repeat the process.
 935                  */
 936                 do {
 937                         if (is_batched_reading)
 938                                 hv_ring_buffer_read_begin(&channel->inbound);
 939
 940                         channel->on_channel_callback(arg);
 941
 942                         if (is_batched_reading)
 943                                 bytes_to_read =
 944                                     hv_ring_buffer_read_end(&channel->inbound);
 945                         else
 946                                 bytes_to_read = 0;
 947                 } while (is_batched_reading && (bytes_to_read != 0));
 948         }
 949         // mtx_unlock(&channel->inbound_lock);
 950 }