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