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/kernel.h>
  34 #include <sys/malloc.h>
  35 #include <sys/systm.h>
  36 #include <sys/mbuf.h>
  37 #include <sys/lock.h>
  38 #include <sys/mutex.h>
  39 #include <machine/bus.h>
  40 #include <vm/vm.h>
  41 #include <vm/vm_param.h>
  42 #include <vm/pmap.h>
  43
  44 #include "hv_vmbus_priv.h"
  45
  46 static int      vmbus_channel_create_gpadl_header(
  47                         /* must be phys and virt contiguous*/
  48                         void*                           contig_buffer,
  49                         /* page-size multiple */
  50                         uint32_t                        size,
  51                         hv_vmbus_channel_msg_info**     msg_info,
  52                         uint32_t*                       message_count);
  53
  54 static void     vmbus_channel_set_event(hv_vmbus_channel* channel);
  55 static void     VmbusProcessChannelEvent(void* channel, int pending);
  56
  57 /**
  58  *  @brief Trigger an event notification on the specified channel
  59  */
  60 static void
  61 vmbus_channel_set_event(hv_vmbus_channel *channel)
  62 {
  63         hv_vmbus_monitor_page *monitor_page;
  64
  65         if (channel->offer_msg.monitor_allocated) {
  66                 /* Each uint32_t represents 32 channels */
  67                 synch_set_bit((channel->offer_msg.child_rel_id & 31),
  68                         ((uint32_t *)hv_vmbus_g_connection.send_interrupt_page
  69                                 + ((channel->offer_msg.child_rel_id >> 5))));
  70
  71                 monitor_page = (hv_vmbus_monitor_page *)
  72                         hv_vmbus_g_connection.monitor_page_2;
  73
  74                 synch_set_bit(channel->monitor_bit,
  75                         (uint32_t *)&monitor_page->
  76                                 trigger_group[channel->monitor_group].u.pending);
  77         } else {
  78                 hv_vmbus_set_event(channel);
  79         }
  80
  81 }
  82
  83 /**
  84  * @brief Open the specified channel
  85  */
  86 int
  87 hv_vmbus_channel_open(
  88         hv_vmbus_channel*               new_channel,
  89         uint32_t                        send_ring_buffer_size,
  90         uint32_t                        recv_ring_buffer_size,
  91         void*                           user_data,
  92         uint32_t                        user_data_len,
  93         hv_vmbus_pfn_channel_callback   pfn_on_channel_callback,
  94         void*                           context)
  95 {
  96
  97         int ret = 0;
  98         void *in, *out;
  99         hv_vmbus_channel_open_channel*  open_msg;
 100         hv_vmbus_channel_msg_info*      open_info;
 101
 102         mtx_lock(&new_channel->sc_lock);
 103         if (new_channel->state == HV_CHANNEL_OPEN_STATE) {
 104             new_channel->state = HV_CHANNEL_OPENING_STATE;
 105         } else {
 106             mtx_unlock(&new_channel->sc_lock);
 107             if(bootverbose)
 108                 printf("VMBUS: Trying to open channel <%p> which in "
 109                     "%d state.\n", new_channel, new_channel->state);
 110             return (EINVAL);
 111         }
 112         mtx_unlock(&new_channel->sc_lock);
 113
 114         new_channel->on_channel_callback = pfn_on_channel_callback;
 115         new_channel->channel_callback_context = context;
 116
 117         new_channel->rxq = hv_vmbus_g_context.hv_event_queue[new_channel->target_cpu];
 118         TASK_INIT(&new_channel->channel_task, 0, VmbusProcessChannelEvent, new_channel);
 119
 120         /* Allocate the ring buffer */
 121         out = contigmalloc((send_ring_buffer_size + recv_ring_buffer_size),
 122             M_DEVBUF, M_ZERO, 0UL, BUS_SPACE_MAXADDR, PAGE_SIZE, 0);
 123         KASSERT(out != NULL,
 124             ("Error VMBUS: contigmalloc failed to allocate Ring Buffer!"));
 125         if (out == NULL)
 126                 return (ENOMEM);
 127
 128         in = ((uint8_t *) out + send_ring_buffer_size);
 129
 130         new_channel->ring_buffer_pages = out;
 131         new_channel->ring_buffer_page_count = (send_ring_buffer_size +
 132             recv_ring_buffer_size) >> PAGE_SHIFT;
 133         new_channel->ring_buffer_size = send_ring_buffer_size +
 134             recv_ring_buffer_size;
 135
 136         hv_vmbus_ring_buffer_init(
 137                 &new_channel->outbound,
 138                 out,
 139                 send_ring_buffer_size);
 140
 141         hv_vmbus_ring_buffer_init(
 142                 &new_channel->inbound,
 143                 in,
 144                 recv_ring_buffer_size);
 145
 146         /**
 147          * Establish the gpadl for the ring buffer
 148          */
 149         new_channel->ring_buffer_gpadl_handle = 0;
 150
 151         ret = hv_vmbus_channel_establish_gpadl(new_channel,
 152                 new_channel->outbound.ring_buffer,
 153                 send_ring_buffer_size + recv_ring_buffer_size,
 154                 &new_channel->ring_buffer_gpadl_handle);
 155
 156         /**
 157          * Create and init the channel open message
 158          */
 159         open_info = (hv_vmbus_channel_msg_info*) malloc(
 160                 sizeof(hv_vmbus_channel_msg_info) +
 161                         sizeof(hv_vmbus_channel_open_channel),
 162                 M_DEVBUF,
 163                 M_NOWAIT);
 164         KASSERT(open_info != NULL,
 165             ("Error VMBUS: malloc failed to allocate Open Channel message!"));
 166
 167         if (open_info == NULL)
 168                 return (ENOMEM);
 169
 170         sema_init(&open_info->wait_sema, 0, "Open Info Sema");
 171
 172         open_msg = (hv_vmbus_channel_open_channel*) open_info->msg;
 173         open_msg->header.message_type = HV_CHANNEL_MESSAGE_OPEN_CHANNEL;
 174         open_msg->open_id = new_channel->offer_msg.child_rel_id;
 175         open_msg->child_rel_id = new_channel->offer_msg.child_rel_id;
 176         open_msg->ring_buffer_gpadl_handle =
 177                 new_channel->ring_buffer_gpadl_handle;
 178         open_msg->downstream_ring_buffer_page_offset = send_ring_buffer_size
 179                 >> PAGE_SHIFT;
 180         open_msg->target_vcpu = new_channel->target_vcpu;
 181
 182         if (user_data_len)
 183                 memcpy(open_msg->user_data, user_data, user_data_len);
 184
 185         mtx_lock_spin(&hv_vmbus_g_connection.channel_msg_lock);
 186         TAILQ_INSERT_TAIL(
 187                 &hv_vmbus_g_connection.channel_msg_anchor,
 188                 open_info,
 189                 msg_list_entry);
 190         mtx_unlock_spin(&hv_vmbus_g_connection.channel_msg_lock);
 191
 192         ret = hv_vmbus_post_message(
 193                 open_msg, sizeof(hv_vmbus_channel_open_channel));
 194
 195         if (ret != 0)
 196             goto cleanup;
 197
 198         ret = sema_timedwait(&open_info->wait_sema, 5 * hz); /* KYS 5 seconds */
 199
 200         if (ret) {
 201             if(bootverbose)
 202                 printf("VMBUS: channel <%p> open timeout.\n", new_channel);
 203             goto cleanup;
 204         }
 205
 206         if (open_info->response.open_result.status == 0) {
 207             new_channel->state = HV_CHANNEL_OPENED_STATE;
 208             if(bootverbose)
 209                 printf("VMBUS: channel <%p> open success.\n", new_channel);
 210         } else {
 211             if(bootverbose)
 212                 printf("Error VMBUS: channel <%p> open failed - %d!\n",
 213                         new_channel, open_info->response.open_result.status);
 214         }
 215
 216         cleanup:
 217         mtx_lock_spin(&hv_vmbus_g_connection.channel_msg_lock);
 218         TAILQ_REMOVE(
 219                 &hv_vmbus_g_connection.channel_msg_anchor,
 220                 open_info,
 221                 msg_list_entry);
 222         mtx_unlock_spin(&hv_vmbus_g_connection.channel_msg_lock);
 223         sema_destroy(&open_info->wait_sema);
 224         free(open_info, M_DEVBUF);
 225
 226         return (ret);
 227 }
 228
 229 /**
 230  * @brief Create a gpadl for the specified buffer
 231  */
 232 static int
 233 vmbus_channel_create_gpadl_header(
 234         void*                           contig_buffer,
 235         uint32_t                        size,   /* page-size multiple */
 236         hv_vmbus_channel_msg_info**     msg_info,
 237         uint32_t*                       message_count)
 238 {
 239         int                             i;
 240         int                             page_count;
 241         unsigned long long              pfn;
 242         uint32_t                        msg_size;
 243         hv_vmbus_channel_gpadl_header*  gpa_header;
 244         hv_vmbus_channel_gpadl_body*    gpadl_body;
 245         hv_vmbus_channel_msg_info*      msg_header;
 246         hv_vmbus_channel_msg_info*      msg_body;
 247
 248         int pfnSum, pfnCount, pfnLeft, pfnCurr, pfnSize;
 249
 250         page_count = size >> PAGE_SHIFT;
 251         pfn = hv_get_phys_addr(contig_buffer) >> PAGE_SHIFT;
 252
 253         /*do we need a gpadl body msg */
 254         pfnSize = HV_MAX_SIZE_CHANNEL_MESSAGE
 255             - sizeof(hv_vmbus_channel_gpadl_header)
 256             - sizeof(hv_gpa_range);
 257         pfnCount = pfnSize / sizeof(uint64_t);
 258
 259         if (page_count > pfnCount) { /* if(we need a gpadl body)        */
 260             /* fill in the header               */
 261             msg_size = sizeof(hv_vmbus_channel_msg_info)
 262                 + sizeof(hv_vmbus_channel_gpadl_header)
 263                 + sizeof(hv_gpa_range)
 264                 + pfnCount * sizeof(uint64_t);
 265             msg_header = malloc(msg_size, M_DEVBUF, M_NOWAIT | M_ZERO);
 266             KASSERT(
 267                 msg_header != NULL,
 268                 ("Error VMBUS: malloc failed to allocate Gpadl Message!"));
 269             if (msg_header == NULL)
 270                 return (ENOMEM);
 271
 272             TAILQ_INIT(&msg_header->sub_msg_list_anchor);
 273             msg_header->message_size = msg_size;
 274
 275             gpa_header = (hv_vmbus_channel_gpadl_header*) msg_header->msg;
 276             gpa_header->range_count = 1;
 277             gpa_header->range_buf_len = sizeof(hv_gpa_range)
 278                 + page_count * sizeof(uint64_t);
 279             gpa_header->range[0].byte_offset = 0;
 280             gpa_header->range[0].byte_count = size;
 281             for (i = 0; i < pfnCount; i++) {
 282                 gpa_header->range[0].pfn_array[i] = pfn + i;
 283             }
 284             *msg_info = msg_header;
 285             *message_count = 1;
 286
 287             pfnSum = pfnCount;
 288             pfnLeft = page_count - pfnCount;
 289
 290             /*
 291              *  figure out how many pfns we can fit
 292              */
 293             pfnSize = HV_MAX_SIZE_CHANNEL_MESSAGE
 294                 - sizeof(hv_vmbus_channel_gpadl_body);
 295             pfnCount = pfnSize / sizeof(uint64_t);
 296
 297             /*
 298              * fill in the body
 299              */
 300             while (pfnLeft) {
 301                 if (pfnLeft > pfnCount) {
 302                     pfnCurr = pfnCount;
 303                 } else {
 304                     pfnCurr = pfnLeft;
 305                 }
 306
 307                 msg_size = sizeof(hv_vmbus_channel_msg_info) +
 308                     sizeof(hv_vmbus_channel_gpadl_body) +
 309                     pfnCurr * sizeof(uint64_t);
 310                 msg_body = malloc(msg_size, M_DEVBUF, M_NOWAIT | M_ZERO);
 311                 KASSERT(
 312                     msg_body != NULL,
 313                     ("Error VMBUS: malloc failed to allocate Gpadl msg_body!"));
 314                 if (msg_body == NULL)
 315                     return (ENOMEM);
 316
 317                 msg_body->message_size = msg_size;
 318                 (*message_count)++;
 319                 gpadl_body =
 320                     (hv_vmbus_channel_gpadl_body*) msg_body->msg;
 321                 /*
 322                  * gpadl_body->gpadl = kbuffer;
 323                  */
 324                 for (i = 0; i < pfnCurr; i++) {
 325                     gpadl_body->pfn[i] = pfn + pfnSum + i;
 326                 }
 327
 328                 TAILQ_INSERT_TAIL(
 329                     &msg_header->sub_msg_list_anchor,
 330                     msg_body,
 331                     msg_list_entry);
 332                 pfnSum += pfnCurr;
 333                 pfnLeft -= pfnCurr;
 334             }
 335         } else { /* else everything fits in a header */
 336
 337             msg_size = sizeof(hv_vmbus_channel_msg_info) +
 338                 sizeof(hv_vmbus_channel_gpadl_header) +
 339                 sizeof(hv_gpa_range) +
 340                 page_count * sizeof(uint64_t);
 341             msg_header = malloc(msg_size, M_DEVBUF, M_NOWAIT | M_ZERO);
 342             KASSERT(
 343                 msg_header != NULL,
 344                 ("Error VMBUS: malloc failed to allocate Gpadl Message!"));
 345             if (msg_header == NULL)
 346                 return (ENOMEM);
 347
 348             msg_header->message_size = msg_size;
 349
 350             gpa_header = (hv_vmbus_channel_gpadl_header*) msg_header->msg;
 351             gpa_header->range_count = 1;
 352             gpa_header->range_buf_len = sizeof(hv_gpa_range) +
 353                 page_count * sizeof(uint64_t);
 354             gpa_header->range[0].byte_offset = 0;
 355             gpa_header->range[0].byte_count = size;
 356             for (i = 0; i < page_count; i++) {
 357                 gpa_header->range[0].pfn_array[i] = pfn + i;
 358             }
 359
 360             *msg_info = msg_header;
 361             *message_count = 1;
 362         }
 363
 364         return (0);
 365 }
 366
 367 /**
 368  * @brief Establish a GPADL for the specified buffer
 369  */
 370 int
 371 hv_vmbus_channel_establish_gpadl(
 372         hv_vmbus_channel*       channel,
 373         void*                   contig_buffer,
 374         uint32_t                size, /* page-size multiple */
 375         uint32_t*               gpadl_handle)
 376
 377 {
 378         int ret = 0;
 379         hv_vmbus_channel_gpadl_header*  gpadl_msg;
 380         hv_vmbus_channel_gpadl_body*    gpadl_body;
 381         hv_vmbus_channel_msg_info*      msg_info;
 382         hv_vmbus_channel_msg_info*      sub_msg_info;
 383         uint32_t                        msg_count;
 384         hv_vmbus_channel_msg_info*      curr;
 385         uint32_t                        next_gpadl_handle;
 386
 387         next_gpadl_handle = atomic_fetchadd_int(
 388             &hv_vmbus_g_connection.next_gpadl_handle, 1);
 389
 390         ret = vmbus_channel_create_gpadl_header(
 391                 contig_buffer, size, &msg_info, &msg_count);
 392
 393         if(ret != 0) {
 394                 /*
 395                  * XXX
 396                  * We can _not_ even revert the above incremental,
 397                  * if multiple GPADL establishments are running
 398                  * parallelly, decrement the global next_gpadl_handle
 399                  * is calling for _big_ trouble.  A better solution
 400                  * is to have a 0-based GPADL id bitmap ...
 401                  */
 402                 return ret;
 403         }
 404
 405         sema_init(&msg_info->wait_sema, 0, "Open Info Sema");
 406         gpadl_msg = (hv_vmbus_channel_gpadl_header*) msg_info->msg;
 407         gpadl_msg->header.message_type = HV_CHANNEL_MESSAGEL_GPADL_HEADER;
 408         gpadl_msg->child_rel_id = channel->offer_msg.child_rel_id;
 409         gpadl_msg->gpadl = next_gpadl_handle;
 410
 411         mtx_lock_spin(&hv_vmbus_g_connection.channel_msg_lock);
 412         TAILQ_INSERT_TAIL(
 413                 &hv_vmbus_g_connection.channel_msg_anchor,
 414                 msg_info,
 415                 msg_list_entry);
 416
 417         mtx_unlock_spin(&hv_vmbus_g_connection.channel_msg_lock);
 418
 419         ret = hv_vmbus_post_message(
 420                 gpadl_msg,
 421                 msg_info->message_size -
 422                     (uint32_t) sizeof(hv_vmbus_channel_msg_info));
 423
 424         if (ret != 0)
 425             goto cleanup;
 426
 427         if (msg_count > 1) {
 428             TAILQ_FOREACH(curr,
 429                     &msg_info->sub_msg_list_anchor, msg_list_entry) {
 430                 sub_msg_info = curr;
 431                 gpadl_body =
 432                     (hv_vmbus_channel_gpadl_body*) sub_msg_info->msg;
 433
 434                 gpadl_body->header.message_type =
 435                     HV_CHANNEL_MESSAGE_GPADL_BODY;
 436                 gpadl_body->gpadl = next_gpadl_handle;
 437
 438                 ret = hv_vmbus_post_message(
 439                         gpadl_body,
 440                         sub_msg_info->message_size
 441                             - (uint32_t) sizeof(hv_vmbus_channel_msg_info));
 442                  /* if (the post message failed) give up and clean up */
 443                 if(ret != 0)
 444                     goto cleanup;
 445             }
 446         }
 447
 448         ret = sema_timedwait(&msg_info->wait_sema, 5 * hz); /* KYS 5 seconds*/
 449         if (ret != 0)
 450             goto cleanup;
 451
 452         *gpadl_handle = gpadl_msg->gpadl;
 453
 454 cleanup:
 455
 456         mtx_lock_spin(&hv_vmbus_g_connection.channel_msg_lock);
 457         TAILQ_REMOVE(&hv_vmbus_g_connection.channel_msg_anchor,
 458                 msg_info, msg_list_entry);
 459         mtx_unlock_spin(&hv_vmbus_g_connection.channel_msg_lock);
 460
 461         sema_destroy(&msg_info->wait_sema);
 462         free(msg_info, M_DEVBUF);
 463
 464         return (ret);
 465 }
 466
 467 /**
 468  * @brief Teardown the specified GPADL handle
 469  */
 470 int
 471 hv_vmbus_channel_teardown_gpdal(
 472         hv_vmbus_channel*       channel,
 473         uint32_t                gpadl_handle)
 474 {
 475         int                                     ret = 0;
 476         hv_vmbus_channel_gpadl_teardown*        msg;
 477         hv_vmbus_channel_msg_info*              info;
 478
 479         info = (hv_vmbus_channel_msg_info *)
 480                 malloc( sizeof(hv_vmbus_channel_msg_info) +
 481                         sizeof(hv_vmbus_channel_gpadl_teardown),
 482                                 M_DEVBUF, M_NOWAIT);
 483         KASSERT(info != NULL,
 484             ("Error VMBUS: malloc failed to allocate Gpadl Teardown Msg!"));
 485         if (info == NULL) {
 486             ret = ENOMEM;
 487             goto cleanup;
 488         }
 489
 490         sema_init(&info->wait_sema, 0, "Open Info Sema");
 491
 492         msg = (hv_vmbus_channel_gpadl_teardown*) info->msg;
 493
 494         msg->header.message_type = HV_CHANNEL_MESSAGE_GPADL_TEARDOWN;
 495         msg->child_rel_id = channel->offer_msg.child_rel_id;
 496         msg->gpadl = gpadl_handle;
 497
 498         mtx_lock_spin(&hv_vmbus_g_connection.channel_msg_lock);
 499         TAILQ_INSERT_TAIL(&hv_vmbus_g_connection.channel_msg_anchor,
 500                         info, msg_list_entry);
 501         mtx_unlock_spin(&hv_vmbus_g_connection.channel_msg_lock);
 502
 503         ret = hv_vmbus_post_message(msg,
 504                         sizeof(hv_vmbus_channel_gpadl_teardown));
 505         if (ret != 0)
 506             goto cleanup;
 507
 508         ret = sema_timedwait(&info->wait_sema, 5 * hz); /* KYS 5 seconds */
 509
 510 cleanup:
 511         /*
 512          * Received a torndown response
 513          */
 514         mtx_lock_spin(&hv_vmbus_g_connection.channel_msg_lock);
 515         TAILQ_REMOVE(&hv_vmbus_g_connection.channel_msg_anchor,
 516                         info, msg_list_entry);
 517         mtx_unlock_spin(&hv_vmbus_g_connection.channel_msg_lock);
 518         sema_destroy(&info->wait_sema);
 519         free(info, M_DEVBUF);
 520
 521         return (ret);
 522 }
 523
 524 static void
 525 hv_vmbus_channel_close_internal(hv_vmbus_channel *channel)
 526 {
 527         int ret = 0;
 528         struct taskqueue *rxq = channel->rxq;
 529         hv_vmbus_channel_close_channel* msg;
 530         hv_vmbus_channel_msg_info* info;
 531
 532         channel->state = HV_CHANNEL_OPEN_STATE;
 533         channel->sc_creation_callback = NULL;
 534
 535         /*
 536          * set rxq to NULL to avoid more requests be scheduled
 537          */
 538         channel->rxq = NULL;
 539         taskqueue_drain(rxq, &channel->channel_task);
 540         /*
 541          * Grab the lock to prevent race condition when a packet received
 542          * and unloading driver is in the process.
 543          */
 544         mtx_lock(&channel->inbound_lock);
 545         channel->on_channel_callback = NULL;
 546         mtx_unlock(&channel->inbound_lock);
 547
 548         /**
 549          * Send a closing message
 550          */
 551         info = (hv_vmbus_channel_msg_info *)
 552                 malloc( sizeof(hv_vmbus_channel_msg_info) +
 553                         sizeof(hv_vmbus_channel_close_channel),
 554                                 M_DEVBUF, M_NOWAIT);
 555         KASSERT(info != NULL, ("VMBUS: malloc failed hv_vmbus_channel_close!"));
 556         if(info == NULL)
 557             return;
 558
 559         msg = (hv_vmbus_channel_close_channel*) info->msg;
 560         msg->header.message_type = HV_CHANNEL_MESSAGE_CLOSE_CHANNEL;
 561         msg->child_rel_id = channel->offer_msg.child_rel_id;
 562
 563         ret = hv_vmbus_post_message(
 564                 msg, sizeof(hv_vmbus_channel_close_channel));
 565
 566         /* Tear down the gpadl for the channel's ring buffer */
 567         if (channel->ring_buffer_gpadl_handle) {
 568                 hv_vmbus_channel_teardown_gpdal(channel,
 569                         channel->ring_buffer_gpadl_handle);
 570         }
 571
 572         /* TODO: Send a msg to release the childRelId */
 573
 574         /* cleanup the ring buffers for this channel */
 575         hv_ring_buffer_cleanup(&channel->outbound);
 576         hv_ring_buffer_cleanup(&channel->inbound);
 577
 578         contigfree(channel->ring_buffer_pages, channel->ring_buffer_size,
 579             M_DEVBUF);
 580
 581         free(info, M_DEVBUF);
 582 }
 583
 584 /**
 585  * @brief Close the specified channel
 586  */
 587 void
 588 hv_vmbus_channel_close(hv_vmbus_channel *channel)
 589 {
 590         hv_vmbus_channel*       sub_channel;
 591
 592         if (channel->primary_channel != NULL) {
 593                 /*
 594                  * We only close multi-channels when the primary is
 595                  * closed.
 596                  */
 597                 return;
 598         }
 599
 600         /*
 601          * Close all multi-channels first.
 602          */
 603         TAILQ_FOREACH(sub_channel, &channel->sc_list_anchor,
 604             sc_list_entry) {
 605                 if (sub_channel->state != HV_CHANNEL_OPENED_STATE)
 606                         continue;
 607                 hv_vmbus_channel_close_internal(sub_channel);
 608         }
 609         /*
 610          * Then close the primary channel.
 611          */
 612         hv_vmbus_channel_close_internal(channel);
 613 }
 614
 615 /**
 616  * @brief Send the specified buffer on the given channel
 617  */
 618 int
 619 hv_vmbus_channel_send_packet(
 620         hv_vmbus_channel*       channel,
 621         void*                   buffer,
 622         uint32_t                buffer_len,
 623         uint64_t                request_id,
 624         hv_vmbus_packet_type    type,
 625         uint32_t                flags)
 626 {
 627         int                     ret = 0;
 628         hv_vm_packet_descriptor desc;
 629         uint32_t                packet_len;
 630         uint64_t                aligned_data;
 631         uint32_t                packet_len_aligned;
 632         boolean_t               need_sig;
 633         hv_vmbus_sg_buffer_list buffer_list[3];
 634
 635         packet_len = sizeof(hv_vm_packet_descriptor) + buffer_len;
 636         packet_len_aligned = HV_ALIGN_UP(packet_len, sizeof(uint64_t));
 637         aligned_data = 0;
 638
 639         /* Setup the descriptor */
 640         desc.type = type;   /* HV_VMBUS_PACKET_TYPE_DATA_IN_BAND;             */
 641         desc.flags = flags; /* HV_VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED */
 642                             /* in 8-bytes granularity */
 643         desc.data_offset8 = sizeof(hv_vm_packet_descriptor) >> 3;
 644         desc.length8 = (uint16_t) (packet_len_aligned >> 3);
 645         desc.transaction_id = request_id;
 646
 647         buffer_list[0].data = &desc;
 648         buffer_list[0].length = sizeof(hv_vm_packet_descriptor);
 649
 650         buffer_list[1].data = buffer;
 651         buffer_list[1].length = buffer_len;
 652
 653         buffer_list[2].data = &aligned_data;
 654         buffer_list[2].length = packet_len_aligned - packet_len;
 655
 656         ret = hv_ring_buffer_write(&channel->outbound, buffer_list, 3,
 657             &need_sig);
 658
 659         /* TODO: We should determine if this is optional */
 660         if (ret == 0 && need_sig) {
 661                 vmbus_channel_set_event(channel);
 662         }
 663
 664         return (ret);
 665 }
 666
 667 /**
 668  * @brief Send a range of single-page buffer packets using
 669  * a GPADL Direct packet type
 670  */
 671 int
 672 hv_vmbus_channel_send_packet_pagebuffer(
 673         hv_vmbus_channel*       channel,
 674         hv_vmbus_page_buffer    page_buffers[],
 675         uint32_t                page_count,
 676         void*                   buffer,
 677         uint32_t                buffer_len,
 678         uint64_t                request_id)
 679 {
 680
 681         int                                     ret = 0;
 682         boolean_t                               need_sig;
 683         uint32_t                                packet_len;
 684         uint32_t                                page_buflen;
 685         uint32_t                                packetLen_aligned;
 686         hv_vmbus_sg_buffer_list                 buffer_list[4];
 687         hv_vmbus_channel_packet_page_buffer     desc;
 688         uint32_t                                descSize;
 689         uint64_t                                alignedData = 0;
 690
 691         if (page_count > HV_MAX_PAGE_BUFFER_COUNT)
 692                 return (EINVAL);
 693
 694         /*
 695          * Adjust the size down since hv_vmbus_channel_packet_page_buffer
 696          *  is the largest size we support
 697          */
 698         descSize = __offsetof(hv_vmbus_channel_packet_page_buffer, range);
 699         page_buflen = sizeof(hv_vmbus_page_buffer) * page_count;
 700         packet_len = descSize + page_buflen + buffer_len;
 701         packetLen_aligned = HV_ALIGN_UP(packet_len, sizeof(uint64_t));
 702
 703         /* Setup the descriptor */
 704         desc.type = HV_VMBUS_PACKET_TYPE_DATA_USING_GPA_DIRECT;
 705         desc.flags = HV_VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED;
 706         /* in 8-bytes granularity */
 707         desc.data_offset8 = (descSize + page_buflen) >> 3;
 708         desc.length8 = (uint16_t) (packetLen_aligned >> 3);
 709         desc.transaction_id = request_id;
 710         desc.range_count = page_count;
 711
 712         buffer_list[0].data = &desc;
 713         buffer_list[0].length = descSize;
 714
 715         buffer_list[1].data = page_buffers;
 716         buffer_list[1].length = page_buflen;
 717
 718         buffer_list[2].data = buffer;
 719         buffer_list[2].length = buffer_len;
 720
 721         buffer_list[3].data = &alignedData;
 722         buffer_list[3].length = packetLen_aligned - packet_len;
 723
 724         ret = hv_ring_buffer_write(&channel->outbound, buffer_list, 4,
 725             &need_sig);
 726
 727         /* TODO: We should determine if this is optional */
 728         if (ret == 0 && need_sig) {
 729                 vmbus_channel_set_event(channel);
 730         }
 731
 732         return (ret);
 733 }
 734
 735 /**
 736  * @brief Send a multi-page buffer packet using a GPADL Direct packet type
 737  */
 738 int
 739 hv_vmbus_channel_send_packet_multipagebuffer(
 740         hv_vmbus_channel*               channel,
 741         hv_vmbus_multipage_buffer*      multi_page_buffer,
 742         void*                           buffer,
 743         uint32_t                        buffer_len,
 744         uint64_t                        request_id)
 745 {
 746
 747         int                     ret = 0;
 748         uint32_t                desc_size;
 749         boolean_t               need_sig;
 750         uint32_t                packet_len;
 751         uint32_t                packet_len_aligned;
 752         uint32_t                pfn_count;
 753         uint64_t                aligned_data = 0;
 754         hv_vmbus_sg_buffer_list buffer_list[3];
 755         hv_vmbus_channel_packet_multipage_buffer desc;
 756
 757         pfn_count =
 758             HV_NUM_PAGES_SPANNED(
 759                     multi_page_buffer->offset,
 760                     multi_page_buffer->length);
 761
 762         if ((pfn_count == 0) || (pfn_count > HV_MAX_MULTIPAGE_BUFFER_COUNT))
 763             return (EINVAL);
 764         /*
 765          * Adjust the size down since hv_vmbus_channel_packet_multipage_buffer
 766          * is the largest size we support
 767          */
 768         desc_size =
 769             sizeof(hv_vmbus_channel_packet_multipage_buffer) -
 770                     ((HV_MAX_MULTIPAGE_BUFFER_COUNT - pfn_count) *
 771                         sizeof(uint64_t));
 772         packet_len = desc_size + buffer_len;
 773         packet_len_aligned = HV_ALIGN_UP(packet_len, sizeof(uint64_t));
 774
 775         /*
 776          * Setup the descriptor
 777          */
 778         desc.type = HV_VMBUS_PACKET_TYPE_DATA_USING_GPA_DIRECT;
 779         desc.flags = HV_VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED;
 780         desc.data_offset8 = desc_size >> 3; /* in 8-bytes granularity */
 781         desc.length8 = (uint16_t) (packet_len_aligned >> 3);
 782         desc.transaction_id = request_id;
 783         desc.range_count = 1;
 784
 785         desc.range.length = multi_page_buffer->length;
 786         desc.range.offset = multi_page_buffer->offset;
 787
 788         memcpy(desc.range.pfn_array, multi_page_buffer->pfn_array,
 789                 pfn_count * sizeof(uint64_t));
 790
 791         buffer_list[0].data = &desc;
 792         buffer_list[0].length = desc_size;
 793
 794         buffer_list[1].data = buffer;
 795         buffer_list[1].length = buffer_len;
 796
 797         buffer_list[2].data = &aligned_data;
 798         buffer_list[2].length = packet_len_aligned - packet_len;
 799
 800         ret = hv_ring_buffer_write(&channel->outbound, buffer_list, 3,
 801             &need_sig);
 802
 803         /* TODO: We should determine if this is optional */
 804         if (ret == 0 && need_sig) {
 805             vmbus_channel_set_event(channel);
 806         }
 807
 808         return (ret);
 809 }
 810
 811 /**
 812  * @brief Retrieve the user packet on the specified channel
 813  */
 814 int
 815 hv_vmbus_channel_recv_packet(
 816         hv_vmbus_channel*       channel,
 817         void*                   Buffer,
 818         uint32_t                buffer_len,
 819         uint32_t*               buffer_actual_len,
 820         uint64_t*               request_id)
 821 {
 822         int                     ret;
 823         uint32_t                user_len;
 824         uint32_t                packet_len;
 825         hv_vm_packet_descriptor desc;
 826
 827         *buffer_actual_len = 0;
 828         *request_id = 0;
 829
 830         ret = hv_ring_buffer_peek(&channel->inbound, &desc,
 831                 sizeof(hv_vm_packet_descriptor));
 832         if (ret != 0)
 833                 return (0);
 834
 835         packet_len = desc.length8 << 3;
 836         user_len = packet_len - (desc.data_offset8 << 3);
 837
 838         *buffer_actual_len = user_len;
 839
 840         if (user_len > buffer_len)
 841                 return (EINVAL);
 842
 843         *request_id = desc.transaction_id;
 844
 845         /* Copy over the packet to the user buffer */
 846         ret = hv_ring_buffer_read(&channel->inbound, Buffer, user_len,
 847                 (desc.data_offset8 << 3));
 848
 849         return (0);
 850 }
 851
 852 /**
 853  * @brief Retrieve the raw packet on the specified channel
 854  */
 855 int
 856 hv_vmbus_channel_recv_packet_raw(
 857         hv_vmbus_channel*       channel,
 858         void*                   buffer,
 859         uint32_t                buffer_len,
 860         uint32_t*               buffer_actual_len,
 861         uint64_t*               request_id)
 862 {
 863         int             ret;
 864         uint32_t        packetLen;
 865         uint32_t        userLen;
 866         hv_vm_packet_descriptor desc;
 867
 868         *buffer_actual_len = 0;
 869         *request_id = 0;
 870
 871         ret = hv_ring_buffer_peek(
 872                 &channel->inbound, &desc,
 873                 sizeof(hv_vm_packet_descriptor));
 874
 875         if (ret != 0)
 876             return (0);
 877
 878         packetLen = desc.length8 << 3;
 879         userLen = packetLen - (desc.data_offset8 << 3);
 880
 881         *buffer_actual_len = packetLen;
 882
 883         if (packetLen > buffer_len)
 884             return (ENOBUFS);
 885
 886         *request_id = desc.transaction_id;
 887
 888         /* Copy over the entire packet to the user buffer */
 889         ret = hv_ring_buffer_read(&channel->inbound, buffer, packetLen, 0);
 890
 891         return (0);
 892 }
 893
 894
 895 /**
 896  * Process a channel event notification
 897  */
 898 static void
 899 VmbusProcessChannelEvent(void* context, int pending)
 900 {
 901         void* arg;
 902         uint32_t bytes_to_read;
 903         hv_vmbus_channel* channel = (hv_vmbus_channel*)context;
 904         boolean_t is_batched_reading;
 905
 906         /**
 907          * Find the channel based on this relid and invokes
 908          * the channel callback to process the event
 909          */
 910
 911         if (channel == NULL) {
 912                 return;
 913         }
 914         /**
 915          * To deal with the race condition where we might
 916          * receive a packet while the relevant driver is
 917          * being unloaded, dispatch the callback while
 918          * holding the channel lock. The unloading driver
 919          * will acquire the same channel lock to set the
 920          * callback to NULL. This closes the window.
 921          */
 922
 923         /*
 924          * Disable the lock due to newly added WITNESS check in r277723.
 925          * Will seek other way to avoid race condition.
 926          * -- whu
 927          */
 928         // mtx_lock(&channel->inbound_lock);
 929         if (channel->on_channel_callback != NULL) {
 930                 arg = channel->channel_callback_context;
 931                 is_batched_reading = channel->batched_reading;
 932                 /*
 933                  * Optimize host to guest signaling by ensuring:
 934                  * 1. While reading the channel, we disable interrupts from
 935                  *    host.
 936                  * 2. Ensure that we process all posted messages from the host
 937                  *    before returning from this callback.
 938                  * 3. Once we return, enable signaling from the host. Once this
 939                  *    state is set we check to see if additional packets are
 940                  *    available to read. In this case we repeat the process.
 941                  */
 942                 do {
 943                         if (is_batched_reading)
 944                                 hv_ring_buffer_read_begin(&channel->inbound);
 945
 946                         channel->on_channel_callback(arg);
 947
 948                         if (is_batched_reading)
 949                                 bytes_to_read =
 950                                     hv_ring_buffer_read_end(&channel->inbound);
 951                         else
 952                                 bytes_to_read = 0;
 953                 } while (is_batched_reading && (bytes_to_read != 0));
 954         }
 955         // mtx_unlock(&channel->inbound_lock);
 956 }