drivers/staging/hv/channel.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, write to the Free Software Foundation, Inc., 59 Temple
  15  * Place - Suite 330, Boston, MA 02111-1307 USA.
  16  *
  17  * Authors:
  18  *   Haiyang Zhang <haiyangz@microsoft.com>
  19  *   Hank Janssen  <hjanssen@microsoft.com>
  20  */
  21 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  22
  23 #include <linux/kernel.h>
  24 #include <linux/sched.h>
  25 #include <linux/wait.h>
  26 #include <linux/mm.h>
  27 #include <linux/slab.h>
  28 #include <linux/module.h>
  29 #include "hv_api.h"
  30 #include "logging.h"
  31 #include "vmbus_private.h"
  32
  33 #define NUM_PAGES_SPANNED(addr, len) \
  34 ((PAGE_ALIGN(addr + len) >> PAGE_SHIFT) - (addr >> PAGE_SHIFT))
  35
  36 /* Internal routines */
  37 static int create_gpadl_header(
  38         void *kbuffer,  /* must be phys and virt contiguous */
  39         u32 size,       /* page-size multiple */
  40         struct vmbus_channel_msginfo **msginfo,
  41         u32 *messagecount);
  42 static void dump_vmbus_channel(struct vmbus_channel *channel);
  43 static void vmbus_setevent(struct vmbus_channel *channel);
  44
  45
  46 #if 0
  47 static void DumpMonitorPage(struct hv_monitor_page *MonitorPage)
  48 {
  49         int i = 0;
  50         int j = 0;
  51
  52         DPRINT_DBG(VMBUS, "monitorPage - %p, trigger state - %d",
  53                    MonitorPage, MonitorPage->trigger_state);
  54
  55         for (i = 0; i < 4; i++)
  56                 DPRINT_DBG(VMBUS, "trigger group (%d) - %llx", i,
  57                            MonitorPage->trigger_group[i].as_uint64);
  58
  59         for (i = 0; i < 4; i++) {
  60                 for (j = 0; j < 32; j++) {
  61                         DPRINT_DBG(VMBUS, "latency (%d)(%d) - %llx", i, j,
  62                                    MonitorPage->latency[i][j]);
  63                 }
  64         }
  65         for (i = 0; i < 4; i++) {
  66                 for (j = 0; j < 32; j++) {
  67                         DPRINT_DBG(VMBUS, "param-conn id (%d)(%d) - %d", i, j,
  68                                MonitorPage->parameter[i][j].connectionid.asu32);
  69                         DPRINT_DBG(VMBUS, "param-flag (%d)(%d) - %d", i, j,
  70                                 MonitorPage->parameter[i][j].flag_number);
  71                 }
  72         }
  73 }
  74 #endif
  75
  76 /*
  77  * vmbus_setevent- Trigger an event notification on the specified
  78  * channel.
  79  */
  80 static void vmbus_setevent(struct vmbus_channel *channel)
  81 {
  82         struct hv_monitor_page *monitorpage;
  83
  84         if (channel->offermsg.monitor_allocated) {
  85                 /* Each u32 represents 32 channels */
  86                 sync_set_bit(channel->offermsg.child_relid & 31,
  87                         (unsigned long *) vmbus_connection.send_int_page +
  88                         (channel->offermsg.child_relid >> 5));
  89
  90                 monitorpage = vmbus_connection.monitor_pages;
  91                 monitorpage++; /* Get the child to parent monitor page */
  92
  93                 sync_set_bit(channel->monitor_bit,
  94                         (unsigned long *)&monitorpage->trigger_group
  95                                         [channel->monitor_grp].pending);
  96
  97         } else {
  98                 vmbus_set_event(channel->offermsg.child_relid);
  99         }
 100 }
 101
 102 #if 0
 103 static void VmbusChannelClearEvent(struct vmbus_channel *channel)
 104 {
 105         struct hv_monitor_page *monitorPage;
 106
 107         if (Channel->offermsg.monitor_allocated) {
 108                 /* Each u32 represents 32 channels */
 109                 sync_clear_bit(Channel->offermsg.child_relid & 31,
 110                           (unsigned long *)vmbus_connection.send_int_page +
 111                           (Channel->offermsg.child_relid >> 5));
 112
 113                 monitorPage = (struct hv_monitor_page *)
 114                         vmbus_connection.monitor_pages;
 115                 monitorPage++; /* Get the child to parent monitor page */
 116
 117                 sync_clear_bit(Channel->monitor_bit,
 118                           (unsigned long *)&monitorPage->trigger_group
 119                                         [Channel->monitor_grp].Pending);
 120         }
 121 }
 122
 123 #endif
 124 /*
 125  * vmbus_get_debug_info -Retrieve various channel debug info
 126  */
 127 void vmbus_get_debug_info(struct vmbus_channel *channel,
 128                               struct vmbus_channel_debug_info *debuginfo)
 129 {
 130         struct hv_monitor_page *monitorpage;
 131         u8 monitor_group = (u8)channel->offermsg.monitorid / 32;
 132         u8 monitor_offset = (u8)channel->offermsg.monitorid % 32;
 133         /* u32 monitorBit       = 1 << monitorOffset; */
 134
 135         debuginfo->relid = channel->offermsg.child_relid;
 136         debuginfo->state = channel->state;
 137         memcpy(&debuginfo->interfacetype,
 138                &channel->offermsg.offer.if_type, sizeof(struct hv_guid));
 139         memcpy(&debuginfo->interface_instance,
 140                &channel->offermsg.offer.if_instance,
 141                sizeof(struct hv_guid));
 142
 143         monitorpage = (struct hv_monitor_page *)vmbus_connection.monitor_pages;
 144
 145         debuginfo->monitorid = channel->offermsg.monitorid;
 146
 147         debuginfo->servermonitor_pending =
 148                         monitorpage->trigger_group[monitor_group].pending;
 149         debuginfo->servermonitor_latency =
 150                         monitorpage->latency[monitor_group][monitor_offset];
 151         debuginfo->servermonitor_connectionid =
 152                         monitorpage->parameter[monitor_group]
 153                                         [monitor_offset].connectionid.u.id;
 154
 155         monitorpage++;
 156
 157         debuginfo->clientmonitor_pending =
 158                         monitorpage->trigger_group[monitor_group].pending;
 159         debuginfo->clientmonitor_latency =
 160                         monitorpage->latency[monitor_group][monitor_offset];
 161         debuginfo->clientmonitor_connectionid =
 162                         monitorpage->parameter[monitor_group]
 163                                         [monitor_offset].connectionid.u.id;
 164
 165         ringbuffer_get_debuginfo(&channel->inbound, &debuginfo->inbound);
 166         ringbuffer_get_debuginfo(&channel->outbound, &debuginfo->outbound);
 167 }
 168
 169 /*
 170  * vmbus_open - Open the specified channel.
 171  */
 172 int vmbus_open(struct vmbus_channel *newchannel, u32 send_ringbuffer_size,
 173                      u32 recv_ringbuffer_size, void *userdata, u32 userdatalen,
 174                      void (*onchannelcallback)(void *context), void *context)
 175 {
 176         struct vmbus_channel_open_channel *openMsg;
 177         struct vmbus_channel_msginfo *openInfo = NULL;
 178         void *in, *out;
 179         unsigned long flags;
 180         int ret, err = 0;
 181
 182         /* Aligned to page size */
 183         /* ASSERT(!(SendRingBufferSize & (PAGE_SIZE - 1))); */
 184         /* ASSERT(!(RecvRingBufferSize & (PAGE_SIZE - 1))); */
 185
 186         newchannel->onchannel_callback = onchannelcallback;
 187         newchannel->channel_callback_context = context;
 188
 189         /* Allocate the ring buffer */
 190         out = (void *)__get_free_pages(GFP_KERNEL|__GFP_ZERO,
 191                 get_order(send_ringbuffer_size + recv_ringbuffer_size));
 192
 193         if (!out)
 194                 return -ENOMEM;
 195
 196         /* ASSERT(((unsigned long)out & (PAGE_SIZE-1)) == 0); */
 197
 198         in = (void *)((unsigned long)out + send_ringbuffer_size);
 199
 200         newchannel->ringbuffer_pages = out;
 201         newchannel->ringbuffer_pagecount = (send_ringbuffer_size +
 202                                            recv_ringbuffer_size) >> PAGE_SHIFT;
 203
 204         ret = hv_ringbuffer_init(
 205                 &newchannel->outbound, out, send_ringbuffer_size);
 206
 207         if (ret != 0) {
 208                 err = ret;
 209                 goto errorout;
 210         }
 211
 212         ret = hv_ringbuffer_init(
 213                 &newchannel->inbound, in, recv_ringbuffer_size);
 214         if (ret != 0) {
 215                 err = ret;
 216                 goto errorout;
 217         }
 218
 219
 220         /* Establish the gpadl for the ring buffer */
 221         newchannel->ringbuffer_gpadlhandle = 0;
 222
 223         ret = vmbus_establish_gpadl(newchannel,
 224                                          newchannel->outbound.ring_buffer,
 225                                          send_ringbuffer_size +
 226                                          recv_ringbuffer_size,
 227                                          &newchannel->ringbuffer_gpadlhandle);
 228
 229         if (ret != 0) {
 230                 err = ret;
 231                 goto errorout;
 232         }
 233
 234         /* Create and init the channel open message */
 235         openInfo = kmalloc(sizeof(*openInfo) +
 236                            sizeof(struct vmbus_channel_open_channel),
 237                            GFP_KERNEL);
 238         if (!openInfo) {
 239                 err = -ENOMEM;
 240                 goto errorout;
 241         }
 242
 243         init_waitqueue_head(&openInfo->waitevent);
 244
 245         openMsg = (struct vmbus_channel_open_channel *)openInfo->msg;
 246         openMsg->header.msgtype = CHANNELMSG_OPENCHANNEL;
 247         openMsg->openid = newchannel->offermsg.child_relid; /* FIXME */
 248         openMsg->child_relid = newchannel->offermsg.child_relid;
 249         openMsg->ringbuffer_gpadlhandle = newchannel->ringbuffer_gpadlhandle;
 250         openMsg->downstream_ringbuffer_pageoffset = send_ringbuffer_size >>
 251                                                   PAGE_SHIFT;
 252         openMsg->server_contextarea_gpadlhandle = 0; /* TODO */
 253
 254         if (userdatalen > MAX_USER_DEFINED_BYTES) {
 255                 err = -EINVAL;
 256                 goto errorout;
 257         }
 258
 259         if (userdatalen)
 260                 memcpy(openMsg->userdata, userdata, userdatalen);
 261
 262         spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
 263         list_add_tail(&openInfo->msglistentry,
 264                       &vmbus_connection.chn_msg_list);
 265         spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
 266
 267         ret = vmbus_post_msg(openMsg,
 268                                sizeof(struct vmbus_channel_open_channel));
 269
 270         if (ret != 0)
 271                 goto Cleanup;
 272
 273         openInfo->wait_condition = 0;
 274         wait_event_timeout(openInfo->waitevent,
 275                         openInfo->wait_condition,
 276                         msecs_to_jiffies(1000));
 277         if (openInfo->wait_condition == 0) {
 278                 err = -ETIMEDOUT;
 279                 goto errorout;
 280         }
 281
 282
 283         if (openInfo->response.open_result.status)
 284                 err = openInfo->response.open_result.status;
 285
 286 Cleanup:
 287         spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
 288         list_del(&openInfo->msglistentry);
 289         spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
 290
 291         kfree(openInfo);
 292         return err;
 293
 294 errorout:
 295         hv_ringbuffer_cleanup(&newchannel->outbound);
 296         hv_ringbuffer_cleanup(&newchannel->inbound);
 297         free_pages((unsigned long)out,
 298                 get_order(send_ringbuffer_size + recv_ringbuffer_size));
 299         kfree(openInfo);
 300         return err;
 301 }
 302 EXPORT_SYMBOL_GPL(vmbus_open);
 303
 304 /*
 305  * dump_gpadl_body - Dump the gpadl body message to the console for
 306  * debugging purposes.
 307  */
 308 static void dump_gpadl_body(struct vmbus_channel_gpadl_body *gpadl, u32 len)
 309 {
 310         int i;
 311         int pfncount;
 312
 313         pfncount = (len - sizeof(struct vmbus_channel_gpadl_body)) /
 314                    sizeof(u64);
 315
 316         DPRINT_DBG(VMBUS, "gpadl body - len %d pfn count %d", len, pfncount);
 317
 318         for (i = 0; i < pfncount; i++)
 319                 DPRINT_DBG(VMBUS, "gpadl body  - %d) pfn %llu",
 320                            i, gpadl->pfn[i]);
 321 }
 322
 323 /*
 324  * dump_gpadl_header - Dump the gpadl header message to the console for
 325  * debugging purposes.
 326  */
 327 static void dump_gpadl_header(struct vmbus_channel_gpadl_header *gpadl)
 328 {
 329         int i, j;
 330         int pagecount;
 331
 332         DPRINT_DBG(VMBUS,
 333                    "gpadl header - relid %d, range count %d, range buflen %d",
 334                    gpadl->child_relid, gpadl->rangecount, gpadl->range_buflen);
 335         for (i = 0; i < gpadl->rangecount; i++) {
 336                 pagecount = gpadl->range[i].byte_count >> PAGE_SHIFT;
 337                 pagecount = (pagecount > 26) ? 26 : pagecount;
 338
 339                 DPRINT_DBG(VMBUS, "gpadl range %d - len %d offset %d "
 340                            "page count %d", i, gpadl->range[i].byte_count,
 341                            gpadl->range[i].byte_offset, pagecount);
 342
 343                 for (j = 0; j < pagecount; j++)
 344                         DPRINT_DBG(VMBUS, "%d) pfn %llu", j,
 345                                    gpadl->range[i].pfn_array[j]);
 346         }
 347 }
 348
 349 /*
 350  * create_gpadl_header - Creates a gpadl for the specified buffer
 351  */
 352 static int create_gpadl_header(void *kbuffer, u32 size,
 353                                          struct vmbus_channel_msginfo **msginfo,
 354                                          u32 *messagecount)
 355 {
 356         int i;
 357         int pagecount;
 358         unsigned long long pfn;
 359         struct vmbus_channel_gpadl_header *gpadl_header;
 360         struct vmbus_channel_gpadl_body *gpadl_body;
 361         struct vmbus_channel_msginfo *msgheader;
 362         struct vmbus_channel_msginfo *msgbody = NULL;
 363         u32 msgsize;
 364
 365         int pfnsum, pfncount, pfnleft, pfncurr, pfnsize;
 366
 367         /* ASSERT((kbuffer & (PAGE_SIZE-1)) == 0); */
 368         /* ASSERT((Size & (PAGE_SIZE-1)) == 0); */
 369
 370         pagecount = size >> PAGE_SHIFT;
 371         pfn = virt_to_phys(kbuffer) >> PAGE_SHIFT;
 372
 373         /* do we need a gpadl body msg */
 374         pfnsize = MAX_SIZE_CHANNEL_MESSAGE -
 375                   sizeof(struct vmbus_channel_gpadl_header) -
 376                   sizeof(struct gpa_range);
 377         pfncount = pfnsize / sizeof(u64);
 378
 379         if (pagecount > pfncount) {
 380                 /* we need a gpadl body */
 381                 /* fill in the header */
 382                 msgsize = sizeof(struct vmbus_channel_msginfo) +
 383                           sizeof(struct vmbus_channel_gpadl_header) +
 384                           sizeof(struct gpa_range) + pfncount * sizeof(u64);
 385                 msgheader =  kzalloc(msgsize, GFP_KERNEL);
 386                 if (!msgheader)
 387                         goto nomem;
 388
 389                 INIT_LIST_HEAD(&msgheader->submsglist);
 390                 msgheader->msgsize = msgsize;
 391
 392                 gpadl_header = (struct vmbus_channel_gpadl_header *)
 393                         msgheader->msg;
 394                 gpadl_header->rangecount = 1;
 395                 gpadl_header->range_buflen = sizeof(struct gpa_range) +
 396                                          pagecount * sizeof(u64);
 397                 gpadl_header->range[0].byte_offset = 0;
 398                 gpadl_header->range[0].byte_count = size;
 399                 for (i = 0; i < pfncount; i++)
 400                         gpadl_header->range[0].pfn_array[i] = pfn+i;
 401                 *msginfo = msgheader;
 402                 *messagecount = 1;
 403
 404                 pfnsum = pfncount;
 405                 pfnleft = pagecount - pfncount;
 406
 407                 /* how many pfns can we fit */
 408                 pfnsize = MAX_SIZE_CHANNEL_MESSAGE -
 409                           sizeof(struct vmbus_channel_gpadl_body);
 410                 pfncount = pfnsize / sizeof(u64);
 411
 412                 /* fill in the body */
 413                 while (pfnleft) {
 414                         if (pfnleft > pfncount)
 415                                 pfncurr = pfncount;
 416                         else
 417                                 pfncurr = pfnleft;
 418
 419                         msgsize = sizeof(struct vmbus_channel_msginfo) +
 420                                   sizeof(struct vmbus_channel_gpadl_body) +
 421                                   pfncurr * sizeof(u64);
 422                         msgbody = kzalloc(msgsize, GFP_KERNEL);
 423                         /* FIXME: we probably need to more if this fails */
 424                         if (!msgbody)
 425                                 goto nomem;
 426                         msgbody->msgsize = msgsize;
 427                         (*messagecount)++;
 428                         gpadl_body =
 429                                 (struct vmbus_channel_gpadl_body *)msgbody->msg;
 430
 431                         /*
 432                          * FIXME:
 433                          * Gpadl is u32 and we are using a pointer which could
 434                          * be 64-bit
 435                          */
 436                         /* gpadl_body->Gpadl = kbuffer; */
 437                         for (i = 0; i < pfncurr; i++)
 438                                 gpadl_body->pfn[i] = pfn + pfnsum + i;
 439
 440                         /* add to msg header */
 441                         list_add_tail(&msgbody->msglistentry,
 442                                       &msgheader->submsglist);
 443                         pfnsum += pfncurr;
 444                         pfnleft -= pfncurr;
 445                 }
 446         } else {
 447                 /* everything fits in a header */
 448                 msgsize = sizeof(struct vmbus_channel_msginfo) +
 449                           sizeof(struct vmbus_channel_gpadl_header) +
 450                           sizeof(struct gpa_range) + pagecount * sizeof(u64);
 451                 msgheader = kzalloc(msgsize, GFP_KERNEL);
 452                 if (msgheader == NULL)
 453                         goto nomem;
 454                 msgheader->msgsize = msgsize;
 455
 456                 gpadl_header = (struct vmbus_channel_gpadl_header *)
 457                         msgheader->msg;
 458                 gpadl_header->rangecount = 1;
 459                 gpadl_header->range_buflen = sizeof(struct gpa_range) +
 460                                          pagecount * sizeof(u64);
 461                 gpadl_header->range[0].byte_offset = 0;
 462                 gpadl_header->range[0].byte_count = size;
 463                 for (i = 0; i < pagecount; i++)
 464                         gpadl_header->range[0].pfn_array[i] = pfn+i;
 465
 466                 *msginfo = msgheader;
 467                 *messagecount = 1;
 468         }
 469
 470         return 0;
 471 nomem:
 472         kfree(msgheader);
 473         kfree(msgbody);
 474         return -ENOMEM;
 475 }
 476
 477 /*
 478  * vmbus_establish_gpadl - Estabish a GPADL for the specified buffer
 479  *
 480  * @channel: a channel
 481  * @kbuffer: from kmalloc
 482  * @size: page-size multiple
 483  * @gpadl_handle: some funky thing
 484  */
 485 int vmbus_establish_gpadl(struct vmbus_channel *channel, void *kbuffer,
 486                                u32 size, u32 *gpadl_handle)
 487 {
 488         struct vmbus_channel_gpadl_header *gpadlmsg;
 489         struct vmbus_channel_gpadl_body *gpadl_body;
 490         /* struct vmbus_channel_gpadl_created *gpadlCreated; */
 491         struct vmbus_channel_msginfo *msginfo = NULL;
 492         struct vmbus_channel_msginfo *submsginfo;
 493         u32 msgcount;
 494         struct list_head *curr;
 495         u32 next_gpadl_handle;
 496         unsigned long flags;
 497         int ret = 0;
 498
 499         next_gpadl_handle = atomic_read(&vmbus_connection.next_gpadl_handle);
 500         atomic_inc(&vmbus_connection.next_gpadl_handle);
 501
 502         ret = create_gpadl_header(kbuffer, size, &msginfo, &msgcount);
 503         if (ret)
 504                 return ret;
 505
 506         init_waitqueue_head(&msginfo->waitevent);
 507
 508         gpadlmsg = (struct vmbus_channel_gpadl_header *)msginfo->msg;
 509         gpadlmsg->header.msgtype = CHANNELMSG_GPADL_HEADER;
 510         gpadlmsg->child_relid = channel->offermsg.child_relid;
 511         gpadlmsg->gpadl = next_gpadl_handle;
 512
 513         dump_gpadl_header(gpadlmsg);
 514
 515         spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
 516         list_add_tail(&msginfo->msglistentry,
 517                       &vmbus_connection.chn_msg_list);
 518
 519         spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
 520
 521         msginfo->wait_condition = 0;
 522         ret = vmbus_post_msg(gpadlmsg, msginfo->msgsize -
 523                                sizeof(*msginfo));
 524         if (ret != 0)
 525                 goto Cleanup;
 526
 527         if (msgcount > 1) {
 528                 list_for_each(curr, &msginfo->submsglist) {
 529
 530                         /* FIXME: should this use list_entry() instead ? */
 531                         submsginfo = (struct vmbus_channel_msginfo *)curr;
 532                         gpadl_body =
 533                              (struct vmbus_channel_gpadl_body *)submsginfo->msg;
 534
 535                         gpadl_body->header.msgtype =
 536                                 CHANNELMSG_GPADL_BODY;
 537                         gpadl_body->gpadl = next_gpadl_handle;
 538
 539                         dump_gpadl_body(gpadl_body, submsginfo->msgsize -
 540                                       sizeof(*submsginfo));
 541                         ret = vmbus_post_msg(gpadl_body,
 542                                                submsginfo->msgsize -
 543                                                sizeof(*submsginfo));
 544                         if (ret != 0)
 545                                 goto Cleanup;
 546
 547                 }
 548         }
 549         wait_event_timeout(msginfo->waitevent,
 550                                 msginfo->wait_condition,
 551                                 msecs_to_jiffies(1000));
 552         BUG_ON(msginfo->wait_condition == 0);
 553
 554
 555         /* At this point, we received the gpadl created msg */
 556         *gpadl_handle = gpadlmsg->gpadl;
 557
 558 Cleanup:
 559         spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
 560         list_del(&msginfo->msglistentry);
 561         spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
 562
 563         kfree(msginfo);
 564         return ret;
 565 }
 566 EXPORT_SYMBOL_GPL(vmbus_establish_gpadl);
 567
 568 /*
 569  * vmbus_teardown_gpadl -Teardown the specified GPADL handle
 570  */
 571 int vmbus_teardown_gpadl(struct vmbus_channel *channel, u32 gpadl_handle)
 572 {
 573         struct vmbus_channel_gpadl_teardown *msg;
 574         struct vmbus_channel_msginfo *info;
 575         unsigned long flags;
 576         int ret;
 577
 578         /* ASSERT(gpadl_handle != 0); */
 579
 580         info = kmalloc(sizeof(*info) +
 581                        sizeof(struct vmbus_channel_gpadl_teardown), GFP_KERNEL);
 582         if (!info)
 583                 return -ENOMEM;
 584
 585         init_waitqueue_head(&info->waitevent);
 586
 587         msg = (struct vmbus_channel_gpadl_teardown *)info->msg;
 588
 589         msg->header.msgtype = CHANNELMSG_GPADL_TEARDOWN;
 590         msg->child_relid = channel->offermsg.child_relid;
 591         msg->gpadl = gpadl_handle;
 592
 593         spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
 594         list_add_tail(&info->msglistentry,
 595                       &vmbus_connection.chn_msg_list);
 596         spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
 597         info->wait_condition = 0;
 598         ret = vmbus_post_msg(msg,
 599                                sizeof(struct vmbus_channel_gpadl_teardown));
 600
 601         BUG_ON(ret != 0);
 602         wait_event_timeout(info->waitevent,
 603                         info->wait_condition, msecs_to_jiffies(1000));
 604         BUG_ON(info->wait_condition == 0);
 605
 606         /* Received a torndown response */
 607         spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
 608         list_del(&info->msglistentry);
 609         spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
 610
 611         kfree(info);
 612         return ret;
 613 }
 614 EXPORT_SYMBOL_GPL(vmbus_teardown_gpadl);
 615
 616 /*
 617  * vmbus_close - Close the specified channel
 618  */
 619 void vmbus_close(struct vmbus_channel *channel)
 620 {
 621         struct vmbus_channel_close_channel *msg;
 622         struct vmbus_channel_msginfo *info;
 623         unsigned long flags;
 624         int ret;
 625
 626         /* Stop callback and cancel the timer asap */
 627         channel->onchannel_callback = NULL;
 628         del_timer_sync(&channel->poll_timer);
 629
 630         /* Send a closing message */
 631         info = kmalloc(sizeof(*info) +
 632                        sizeof(struct vmbus_channel_close_channel), GFP_KERNEL);
 633         /* FIXME: can't do anything other than return here because the
 634          *        function is void */
 635         if (!info)
 636                 return;
 637
 638
 639         msg = (struct vmbus_channel_close_channel *)info->msg;
 640         msg->header.msgtype = CHANNELMSG_CLOSECHANNEL;
 641         msg->child_relid = channel->offermsg.child_relid;
 642
 643         ret = vmbus_post_msg(msg, sizeof(struct vmbus_channel_close_channel));
 644
 645         BUG_ON(ret != 0);
 646         /* Tear down the gpadl for the channel's ring buffer */
 647         if (channel->ringbuffer_gpadlhandle)
 648                 vmbus_teardown_gpadl(channel,
 649                                           channel->ringbuffer_gpadlhandle);
 650
 651         /* TODO: Send a msg to release the childRelId */
 652
 653         /* Cleanup the ring buffers for this channel */
 654         hv_ringbuffer_cleanup(&channel->outbound);
 655         hv_ringbuffer_cleanup(&channel->inbound);
 656
 657         free_pages((unsigned long)channel->ringbuffer_pages,
 658                 get_order(channel->ringbuffer_pagecount * PAGE_SIZE));
 659
 660         kfree(info);
 661
 662         /*
 663          * If we are closing the channel during an error path in
 664          * opening the channel, don't free the channel since the
 665          * caller will free the channel
 666          */
 667
 668         if (channel->state == CHANNEL_OPEN_STATE) {
 669                 spin_lock_irqsave(&vmbus_connection.channel_lock, flags);
 670                 list_del(&channel->listentry);
 671                 spin_unlock_irqrestore(&vmbus_connection.channel_lock, flags);
 672
 673                 free_channel(channel);
 674         }
 675 }
 676 EXPORT_SYMBOL_GPL(vmbus_close);
 677
 678 /**
 679  * vmbus_sendpacket() - Send the specified buffer on the given channel
 680  * @channel: Pointer to vmbus_channel structure.
 681  * @buffer: Pointer to the buffer you want to receive the data into.
 682  * @bufferlen: Maximum size of what the the buffer will hold
 683  * @requestid: Identifier of the request
 684  * @type: Type of packet that is being send e.g. negotiate, time
 685  * packet etc.
 686  *
 687  * Sends data in @buffer directly to hyper-v via the vmbus
 688  * This will send the data unparsed to hyper-v.
 689  *
 690  * Mainly used by Hyper-V drivers.
 691  */
 692 int vmbus_sendpacket(struct vmbus_channel *channel, const void *buffer,
 693                            u32 bufferlen, u64 requestid,
 694                            enum vmbus_packet_type type, u32 flags)
 695 {
 696         struct vmpacket_descriptor desc;
 697         u32 packetlen = sizeof(struct vmpacket_descriptor) + bufferlen;
 698         u32 packetlen_aligned = ALIGN(packetlen, sizeof(u64));
 699         struct scatterlist bufferlist[3];
 700         u64 aligned_data = 0;
 701         int ret;
 702
 703         dump_vmbus_channel(channel);
 704
 705         /* ASSERT((packetLenAligned - packetLen) < sizeof(u64)); */
 706
 707         /* Setup the descriptor */
 708         desc.type = type; /* VmbusPacketTypeDataInBand; */
 709         desc.flags = flags; /* VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED; */
 710         /* in 8-bytes granularity */
 711         desc.offset8 = sizeof(struct vmpacket_descriptor) >> 3;
 712         desc.len8 = (u16)(packetlen_aligned >> 3);
 713         desc.trans_id = requestid;
 714
 715         sg_init_table(bufferlist, 3);
 716         sg_set_buf(&bufferlist[0], &desc, sizeof(struct vmpacket_descriptor));
 717         sg_set_buf(&bufferlist[1], buffer, bufferlen);
 718         sg_set_buf(&bufferlist[2], &aligned_data,
 719                    packetlen_aligned - packetlen);
 720
 721         ret = hv_ringbuffer_write(&channel->outbound, bufferlist, 3);
 722
 723         /* TODO: We should determine if this is optional */
 724         if (ret == 0 && !get_ringbuffer_interrupt_mask(&channel->outbound))
 725                 vmbus_setevent(channel);
 726
 727         return ret;
 728 }
 729 EXPORT_SYMBOL(vmbus_sendpacket);
 730
 731 /*
 732  * vmbus_sendpacket_pagebuffer - Send a range of single-page buffer
 733  * packets using a GPADL Direct packet type.
 734  */
 735 int vmbus_sendpacket_pagebuffer(struct vmbus_channel *channel,
 736                                      struct hv_page_buffer pagebuffers[],
 737                                      u32 pagecount, void *buffer, u32 bufferlen,
 738                                      u64 requestid)
 739 {
 740         int ret;
 741         int i;
 742         struct vmbus_channel_packet_page_buffer desc;
 743         u32 descsize;
 744         u32 packetlen;
 745         u32 packetlen_aligned;
 746         struct scatterlist bufferlist[3];
 747         u64 aligned_data = 0;
 748
 749         if (pagecount > MAX_PAGE_BUFFER_COUNT)
 750                 return -EINVAL;
 751
 752         dump_vmbus_channel(channel);
 753
 754         /*
 755          * Adjust the size down since vmbus_channel_packet_page_buffer is the
 756          * largest size we support
 757          */
 758         descsize = sizeof(struct vmbus_channel_packet_page_buffer) -
 759                           ((MAX_PAGE_BUFFER_COUNT - pagecount) *
 760                           sizeof(struct hv_page_buffer));
 761         packetlen = descsize + bufferlen;
 762         packetlen_aligned = ALIGN(packetlen, sizeof(u64));
 763
 764         /* ASSERT((packetLenAligned - packetLen) < sizeof(u64)); */
 765
 766         /* Setup the descriptor */
 767         desc.type = VM_PKT_DATA_USING_GPA_DIRECT;
 768         desc.flags = VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED;
 769         desc.dataoffset8 = descsize >> 3; /* in 8-bytes grandularity */
 770         desc.length8 = (u16)(packetlen_aligned >> 3);
 771         desc.transactionid = requestid;
 772         desc.rangecount = pagecount;
 773
 774         for (i = 0; i < pagecount; i++) {
 775                 desc.range[i].len = pagebuffers[i].len;
 776                 desc.range[i].offset = pagebuffers[i].offset;
 777                 desc.range[i].pfn        = pagebuffers[i].pfn;
 778         }
 779
 780         sg_init_table(bufferlist, 3);
 781         sg_set_buf(&bufferlist[0], &desc, descsize);
 782         sg_set_buf(&bufferlist[1], buffer, bufferlen);
 783         sg_set_buf(&bufferlist[2], &aligned_data,
 784                 packetlen_aligned - packetlen);
 785
 786         ret = hv_ringbuffer_write(&channel->outbound, bufferlist, 3);
 787
 788         /* TODO: We should determine if this is optional */
 789         if (ret == 0 && !get_ringbuffer_interrupt_mask(&channel->outbound))
 790                 vmbus_setevent(channel);
 791
 792         return ret;
 793 }
 794 EXPORT_SYMBOL_GPL(vmbus_sendpacket_pagebuffer);
 795
 796 /*
 797  * vmbus_sendpacket_multipagebuffer - Send a multi-page buffer packet
 798  * using a GPADL Direct packet type.
 799  */
 800 int vmbus_sendpacket_multipagebuffer(struct vmbus_channel *channel,
 801                                 struct hv_multipage_buffer *multi_pagebuffer,
 802                                 void *buffer, u32 bufferlen, u64 requestid)
 803 {
 804         int ret;
 805         struct vmbus_channel_packet_multipage_buffer desc;
 806         u32 descsize;
 807         u32 packetlen;
 808         u32 packetlen_aligned;
 809         struct scatterlist bufferlist[3];
 810         u64 aligned_data = 0;
 811         u32 pfncount = NUM_PAGES_SPANNED(multi_pagebuffer->offset,
 812                                          multi_pagebuffer->len);
 813
 814         dump_vmbus_channel(channel);
 815
 816         if ((pfncount < 0) || (pfncount > MAX_MULTIPAGE_BUFFER_COUNT))
 817                 return -EINVAL;
 818
 819         /*
 820          * Adjust the size down since vmbus_channel_packet_multipage_buffer is
 821          * the largest size we support
 822          */
 823         descsize = sizeof(struct vmbus_channel_packet_multipage_buffer) -
 824                           ((MAX_MULTIPAGE_BUFFER_COUNT - pfncount) *
 825                           sizeof(u64));
 826         packetlen = descsize + bufferlen;
 827         packetlen_aligned = ALIGN(packetlen, sizeof(u64));
 828
 829         /* ASSERT((packetLenAligned - packetLen) < sizeof(u64)); */
 830
 831         /* Setup the descriptor */
 832         desc.type = VM_PKT_DATA_USING_GPA_DIRECT;
 833         desc.flags = VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED;
 834         desc.dataoffset8 = descsize >> 3; /* in 8-bytes grandularity */
 835         desc.length8 = (u16)(packetlen_aligned >> 3);
 836         desc.transactionid = requestid;
 837         desc.rangecount = 1;
 838
 839         desc.range.len = multi_pagebuffer->len;
 840         desc.range.offset = multi_pagebuffer->offset;
 841
 842         memcpy(desc.range.pfn_array, multi_pagebuffer->pfn_array,
 843                pfncount * sizeof(u64));
 844
 845         sg_init_table(bufferlist, 3);
 846         sg_set_buf(&bufferlist[0], &desc, descsize);
 847         sg_set_buf(&bufferlist[1], buffer, bufferlen);
 848         sg_set_buf(&bufferlist[2], &aligned_data,
 849                 packetlen_aligned - packetlen);
 850
 851         ret = hv_ringbuffer_write(&channel->outbound, bufferlist, 3);
 852
 853         /* TODO: We should determine if this is optional */
 854         if (ret == 0 && !get_ringbuffer_interrupt_mask(&channel->outbound))
 855                 vmbus_setevent(channel);
 856
 857         return ret;
 858 }
 859 EXPORT_SYMBOL_GPL(vmbus_sendpacket_multipagebuffer);
 860
 861 /**
 862  * vmbus_recvpacket() - Retrieve the user packet on the specified channel
 863  * @channel: Pointer to vmbus_channel structure.
 864  * @buffer: Pointer to the buffer you want to receive the data into.
 865  * @bufferlen: Maximum size of what the the buffer will hold
 866  * @buffer_actual_len: The actual size of the data after it was received
 867  * @requestid: Identifier of the request
 868  *
 869  * Receives directly from the hyper-v vmbus and puts the data it received
 870  * into Buffer. This will receive the data unparsed from hyper-v.
 871  *
 872  * Mainly used by Hyper-V drivers.
 873  */
 874 int vmbus_recvpacket(struct vmbus_channel *channel, void *buffer,
 875                         u32 bufferlen, u32 *buffer_actual_len, u64 *requestid)
 876 {
 877         struct vmpacket_descriptor desc;
 878         u32 packetlen;
 879         u32 userlen;
 880         int ret;
 881         unsigned long flags;
 882
 883         *buffer_actual_len = 0;
 884         *requestid = 0;
 885
 886         spin_lock_irqsave(&channel->inbound_lock, flags);
 887
 888         ret = hv_ringbuffer_peek(&channel->inbound, &desc,
 889                              sizeof(struct vmpacket_descriptor));
 890         if (ret != 0) {
 891                 spin_unlock_irqrestore(&channel->inbound_lock, flags);
 892                 return 0;
 893         }
 894
 895         /* VmbusChannelClearEvent(Channel); */
 896
 897         packetlen = desc.len8 << 3;
 898         userlen = packetlen - (desc.offset8 << 3);
 899         /* ASSERT(userLen > 0); */
 900
 901         *buffer_actual_len = userlen;
 902
 903         if (userlen > bufferlen) {
 904                 spin_unlock_irqrestore(&channel->inbound_lock, flags);
 905
 906                 pr_err("Buffer too small - got %d needs %d\n",
 907                            bufferlen, userlen);
 908                 return -1;
 909         }
 910
 911         *requestid = desc.trans_id;
 912
 913         /* Copy over the packet to the user buffer */
 914         ret = hv_ringbuffer_read(&channel->inbound, buffer, userlen,
 915                              (desc.offset8 << 3));
 916
 917         spin_unlock_irqrestore(&channel->inbound_lock, flags);
 918
 919         return 0;
 920 }
 921 EXPORT_SYMBOL(vmbus_recvpacket);
 922
 923 /*
 924  * vmbus_recvpacket_raw - Retrieve the raw packet on the specified channel
 925  */
 926 int vmbus_recvpacket_raw(struct vmbus_channel *channel, void *buffer,
 927                               u32 bufferlen, u32 *buffer_actual_len,
 928                               u64 *requestid)
 929 {
 930         struct vmpacket_descriptor desc;
 931         u32 packetlen;
 932         u32 userlen;
 933         int ret;
 934         unsigned long flags;
 935
 936         *buffer_actual_len = 0;
 937         *requestid = 0;
 938
 939         spin_lock_irqsave(&channel->inbound_lock, flags);
 940
 941         ret = hv_ringbuffer_peek(&channel->inbound, &desc,
 942                              sizeof(struct vmpacket_descriptor));
 943         if (ret != 0) {
 944                 spin_unlock_irqrestore(&channel->inbound_lock, flags);
 945                 return 0;
 946         }
 947
 948         /* VmbusChannelClearEvent(Channel); */
 949
 950         packetlen = desc.len8 << 3;
 951         userlen = packetlen - (desc.offset8 << 3);
 952
 953         *buffer_actual_len = packetlen;
 954
 955         if (packetlen > bufferlen) {
 956                 spin_unlock_irqrestore(&channel->inbound_lock, flags);
 957
 958                 pr_err("Buffer too small - needed %d bytes but "
 959                         "got space for only %d bytes\n",
 960                         packetlen, bufferlen);
 961                 return -2;
 962         }
 963
 964         *requestid = desc.trans_id;
 965
 966         /* Copy over the entire packet to the user buffer */
 967         ret = hv_ringbuffer_read(&channel->inbound, buffer, packetlen, 0);
 968
 969         spin_unlock_irqrestore(&channel->inbound_lock, flags);
 970         return 0;
 971 }
 972 EXPORT_SYMBOL_GPL(vmbus_recvpacket_raw);
 973
 974 /*
 975  * vmbus_onchannel_event - Channel event callback
 976  */
 977 void vmbus_onchannel_event(struct vmbus_channel *channel)
 978 {
 979         dump_vmbus_channel(channel);
 980         /* ASSERT(Channel->OnChannelCallback); */
 981
 982         channel->onchannel_callback(channel->channel_callback_context);
 983
 984         mod_timer(&channel->poll_timer, jiffies + usecs_to_jiffies(100));
 985 }
 986
 987 /*
 988  * vmbus_ontimer - Timer event callback
 989  */
 990 void vmbus_ontimer(unsigned long data)
 991 {
 992         struct vmbus_channel *channel = (struct vmbus_channel *)data;
 993
 994         if (channel->onchannel_callback)
 995                 channel->onchannel_callback(channel->channel_callback_context);
 996 }
 997
 998 /*
 999  * dump_vmbus_channel- Dump vmbus channel info to the console
1000  */
1001 static void dump_vmbus_channel(struct vmbus_channel *channel)
1002 {
1003         DPRINT_DBG(VMBUS, "Channel (%d)", channel->offermsg.child_relid);
1004         dump_ring_info(&channel->outbound, "Outbound ");
1005         dump_ring_info(&channel->inbound, "Inbound ");
1006 }