drivers/hv/hv_util.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (c) 2010, Microsoft Corporation.
   4  *
   5  * Authors:
   6  *   Haiyang Zhang <[email protected]>
   7  *   Hank Janssen  <[email protected]>
   8  */
   9 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  10
  11 #include <linux/kernel.h>
  12 #include <linux/init.h>
  13 #include <linux/module.h>
  14 #include <linux/slab.h>
  15 #include <linux/sysctl.h>
  16 #include <linux/reboot.h>
  17 #include <linux/hyperv.h>
  18 #include <linux/clockchips.h>
  19 #include <linux/ptp_clock_kernel.h>
  20 #include <asm/mshyperv.h>
  21
  22 #include "hyperv_vmbus.h"
  23
  24 #define SD_MAJOR        3
  25 #define SD_MINOR        0
  26 #define SD_MINOR_1      1
  27 #define SD_MINOR_2      2
  28 #define SD_VERSION_3_1  (SD_MAJOR << 16 | SD_MINOR_1)
  29 #define SD_VERSION_3_2  (SD_MAJOR << 16 | SD_MINOR_2)
  30 #define SD_VERSION      (SD_MAJOR << 16 | SD_MINOR)
  31
  32 #define SD_MAJOR_1      1
  33 #define SD_VERSION_1    (SD_MAJOR_1 << 16 | SD_MINOR)
  34
  35 #define TS_MAJOR        4
  36 #define TS_MINOR        0
  37 #define TS_VERSION      (TS_MAJOR << 16 | TS_MINOR)
  38
  39 #define TS_MAJOR_1      1
  40 #define TS_VERSION_1    (TS_MAJOR_1 << 16 | TS_MINOR)
  41
  42 #define TS_MAJOR_3      3
  43 #define TS_VERSION_3    (TS_MAJOR_3 << 16 | TS_MINOR)
  44
  45 #define HB_MAJOR        3
  46 #define HB_MINOR        0
  47 #define HB_VERSION      (HB_MAJOR << 16 | HB_MINOR)
  48
  49 #define HB_MAJOR_1      1
  50 #define HB_VERSION_1    (HB_MAJOR_1 << 16 | HB_MINOR)
  51
  52 static int sd_srv_version;
  53 static int ts_srv_version;
  54 static int hb_srv_version;
  55
  56 #define SD_VER_COUNT 4
  57 static const int sd_versions[] = {
  58         SD_VERSION_3_2,
  59         SD_VERSION_3_1,
  60         SD_VERSION,
  61         SD_VERSION_1
  62 };
  63
  64 #define TS_VER_COUNT 3
  65 static const int ts_versions[] = {
  66         TS_VERSION,
  67         TS_VERSION_3,
  68         TS_VERSION_1
  69 };
  70
  71 #define HB_VER_COUNT 2
  72 static const int hb_versions[] = {
  73         HB_VERSION,
  74         HB_VERSION_1
  75 };
  76
  77 #define FW_VER_COUNT 2
  78 static const int fw_versions[] = {
  79         UTIL_FW_VERSION,
  80         UTIL_WS2K8_FW_VERSION
  81 };
  82
  83 /*
  84  * Send the "hibernate" udev event in a thread context.
  85  */
  86 struct hibernate_work_context {
  87         struct work_struct work;
  88         struct hv_device *dev;
  89 };
  90
  91 static struct hibernate_work_context hibernate_context;
  92 static bool hibernation_supported;
  93
  94 static void send_hibernate_uevent(struct work_struct *work)
  95 {
  96         char *uevent_env[2] = { "EVENT=hibernate", NULL };
  97         struct hibernate_work_context *ctx;
  98
  99         ctx = container_of(work, struct hibernate_work_context, work);
 100
 101         kobject_uevent_env(&ctx->dev->device.kobj, KOBJ_CHANGE, uevent_env);
 102
 103         pr_info("Sent hibernation uevent\n");
 104 }
 105
 106 static int hv_shutdown_init(struct hv_util_service *srv)
 107 {
 108         struct vmbus_channel *channel = srv->channel;
 109
 110         INIT_WORK(&hibernate_context.work, send_hibernate_uevent);
 111         hibernate_context.dev = channel->device_obj;
 112
 113         hibernation_supported = hv_is_hibernation_supported();
 114
 115         return 0;
 116 }
 117
 118 static void shutdown_onchannelcallback(void *context);
 119 static struct hv_util_service util_shutdown = {
 120         .util_cb = shutdown_onchannelcallback,
 121         .util_init = hv_shutdown_init,
 122 };
 123
 124 static int hv_timesync_init(struct hv_util_service *srv);
 125 static int hv_timesync_pre_suspend(void);
 126 static void hv_timesync_deinit(void);
 127
 128 static void timesync_onchannelcallback(void *context);
 129 static struct hv_util_service util_timesynch = {
 130         .util_cb = timesync_onchannelcallback,
 131         .util_init = hv_timesync_init,
 132         .util_pre_suspend = hv_timesync_pre_suspend,
 133         .util_deinit = hv_timesync_deinit,
 134 };
 135
 136 static void heartbeat_onchannelcallback(void *context);
 137 static struct hv_util_service util_heartbeat = {
 138         .util_cb = heartbeat_onchannelcallback,
 139 };
 140
 141 static struct hv_util_service util_kvp = {
 142         .util_cb = hv_kvp_onchannelcallback,
 143         .util_init = hv_kvp_init,
 144         .util_init_transport = hv_kvp_init_transport,
 145         .util_pre_suspend = hv_kvp_pre_suspend,
 146         .util_pre_resume = hv_kvp_pre_resume,
 147         .util_deinit = hv_kvp_deinit,
 148 };
 149
 150 static struct hv_util_service util_vss = {
 151         .util_cb = hv_vss_onchannelcallback,
 152         .util_init = hv_vss_init,
 153         .util_init_transport = hv_vss_init_transport,
 154         .util_pre_suspend = hv_vss_pre_suspend,
 155         .util_pre_resume = hv_vss_pre_resume,
 156         .util_deinit = hv_vss_deinit,
 157 };
 158
 159 static void perform_shutdown(struct work_struct *dummy)
 160 {
 161         orderly_poweroff(true);
 162 }
 163
 164 static void perform_restart(struct work_struct *dummy)
 165 {
 166         orderly_reboot();
 167 }
 168
 169 /*
 170  * Perform the shutdown operation in a thread context.
 171  */
 172 static DECLARE_WORK(shutdown_work, perform_shutdown);
 173
 174 /*
 175  * Perform the restart operation in a thread context.
 176  */
 177 static DECLARE_WORK(restart_work, perform_restart);
 178
 179 static void shutdown_onchannelcallback(void *context)
 180 {
 181         struct vmbus_channel *channel = context;
 182         struct work_struct *work = NULL;
 183         u32 recvlen;
 184         u64 requestid;
 185         u8  *shut_txf_buf = util_shutdown.recv_buffer;
 186
 187         struct shutdown_msg_data *shutdown_msg;
 188
 189         struct icmsg_hdr *icmsghdrp;
 190
 191         if (vmbus_recvpacket(channel, shut_txf_buf, HV_HYP_PAGE_SIZE, &recvlen, &requestid)) {
 192                 pr_err_ratelimited("Shutdown request received. Could not read into shut txf buf\n");
 193                 return;
 194         }
 195
 196         if (!recvlen)
 197                 return;
 198
 199         /* Ensure recvlen is big enough to read header data */
 200         if (recvlen < ICMSG_HDR) {
 201                 pr_err_ratelimited("Shutdown request received. Packet length too small: %d\n",
 202                                    recvlen);
 203                 return;
 204         }
 205
 206         icmsghdrp = (struct icmsg_hdr *)&shut_txf_buf[sizeof(struct vmbuspipe_hdr)];
 207
 208         if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) {
 209                 if (vmbus_prep_negotiate_resp(icmsghdrp,
 210                                 shut_txf_buf, recvlen,
 211                                 fw_versions, FW_VER_COUNT,
 212                                 sd_versions, SD_VER_COUNT,
 213                                 NULL, &sd_srv_version)) {
 214                         pr_info("Shutdown IC version %d.%d\n",
 215                                 sd_srv_version >> 16,
 216                                 sd_srv_version & 0xFFFF);
 217                 }
 218         } else if (icmsghdrp->icmsgtype == ICMSGTYPE_SHUTDOWN) {
 219                 /* Ensure recvlen is big enough to contain shutdown_msg_data struct */
 220                 if (recvlen < ICMSG_HDR + sizeof(struct shutdown_msg_data)) {
 221                         pr_err_ratelimited("Invalid shutdown msg data. Packet length too small: %u\n",
 222                                            recvlen);
 223                         return;
 224                 }
 225
 226                 shutdown_msg = (struct shutdown_msg_data *)&shut_txf_buf[ICMSG_HDR];
 227
 228                 /*
 229                  * shutdown_msg->flags can be 0(shut down), 2(reboot),
 230                  * or 4(hibernate). It may bitwise-OR 1, which means
 231                  * performing the request by force. Linux always tries
 232                  * to perform the request by force.
 233                  */
 234                 switch (shutdown_msg->flags) {
 235                 case 0:
 236                 case 1:
 237                         icmsghdrp->status = HV_S_OK;
 238                         work = &shutdown_work;
 239                         pr_info("Shutdown request received - graceful shutdown initiated\n");
 240                         break;
 241                 case 2:
 242                 case 3:
 243                         icmsghdrp->status = HV_S_OK;
 244                         work = &restart_work;
 245                         pr_info("Restart request received - graceful restart initiated\n");
 246                         break;
 247                 case 4:
 248                 case 5:
 249                         pr_info("Hibernation request received\n");
 250                         icmsghdrp->status = hibernation_supported ?
 251                                 HV_S_OK : HV_E_FAIL;
 252                         if (hibernation_supported)
 253                                 work = &hibernate_context.work;
 254                         break;
 255                 default:
 256                         icmsghdrp->status = HV_E_FAIL;
 257                         pr_info("Shutdown request received - Invalid request\n");
 258                         break;
 259                 }
 260         } else {
 261                 icmsghdrp->status = HV_E_FAIL;
 262                 pr_err_ratelimited("Shutdown request received. Invalid msg type: %d\n",
 263                                    icmsghdrp->icmsgtype);
 264         }
 265
 266         icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION
 267                 | ICMSGHDRFLAG_RESPONSE;
 268
 269         vmbus_sendpacket(channel, shut_txf_buf,
 270                          recvlen, requestid,
 271                          VM_PKT_DATA_INBAND, 0);
 272
 273         if (work)
 274                 schedule_work(work);
 275 }
 276
 277 /*
 278  * Set the host time in a process context.
 279  */
 280 static struct work_struct adj_time_work;
 281
 282 /*
 283  * The last time sample, received from the host. PTP device responds to
 284  * requests by using this data and the current partition-wide time reference
 285  * count.
 286  */
 287 static struct {
 288         u64                             host_time;
 289         u64                             ref_time;
 290         spinlock_t                      lock;
 291 } host_ts;
 292
 293 static bool timesync_implicit;
 294
 295 module_param(timesync_implicit, bool, 0644);
 296 MODULE_PARM_DESC(timesync_implicit, "If set treat SAMPLE as SYNC when clock is behind");
 297
 298 static inline u64 reftime_to_ns(u64 reftime)
 299 {
 300         return (reftime - WLTIMEDELTA) * 100;
 301 }
 302
 303 /*
 304  * Hard coded threshold for host timesync delay: 600 seconds
 305  */
 306 static const u64 HOST_TIMESYNC_DELAY_THRESH = 600 * (u64)NSEC_PER_SEC;
 307
 308 static int hv_get_adj_host_time(struct timespec64 *ts)
 309 {
 310         u64 newtime, reftime, timediff_adj;
 311         unsigned long flags;
 312         int ret = 0;
 313
 314         spin_lock_irqsave(&host_ts.lock, flags);
 315         reftime = hv_read_reference_counter();
 316
 317         /*
 318          * We need to let the caller know that last update from host
 319          * is older than the max allowable threshold. clock_gettime()
 320          * and PTP ioctl do not have a documented error that we could
 321          * return for this specific case. Use ESTALE to report this.
 322          */
 323         timediff_adj = reftime - host_ts.ref_time;
 324         if (timediff_adj * 100 > HOST_TIMESYNC_DELAY_THRESH) {
 325                 pr_warn_once("TIMESYNC IC: Stale time stamp, %llu nsecs old\n",
 326                              (timediff_adj * 100));
 327                 ret = -ESTALE;
 328         }
 329
 330         newtime = host_ts.host_time + timediff_adj;
 331         *ts = ns_to_timespec64(reftime_to_ns(newtime));
 332         spin_unlock_irqrestore(&host_ts.lock, flags);
 333
 334         return ret;
 335 }
 336
 337 static void hv_set_host_time(struct work_struct *work)
 338 {
 339
 340         struct timespec64 ts;
 341
 342         if (!hv_get_adj_host_time(&ts))
 343                 do_settimeofday64(&ts);
 344 }
 345
 346 /*
 347  * Due to a bug on Hyper-V hosts, the sync flag may not always be sent on resume.
 348  * Force a sync if the guest is behind.
 349  */
 350 static inline bool hv_implicit_sync(u64 host_time)
 351 {
 352         struct timespec64 new_ts;
 353         struct timespec64 threshold_ts;
 354
 355         new_ts = ns_to_timespec64(reftime_to_ns(host_time));
 356         ktime_get_real_ts64(&threshold_ts);
 357
 358         threshold_ts.tv_sec += 5;
 359
 360         /*
 361          * If guest behind the host by 5 or more seconds.
 362          */
 363         if (timespec64_compare(&new_ts, &threshold_ts) >= 0)
 364                 return true;
 365
 366         return false;
 367 }
 368
 369 /*
 370  * Synchronize time with host after reboot, restore, etc.
 371  *
 372  * ICTIMESYNCFLAG_SYNC flag bit indicates reboot, restore events of the VM.
 373  * After reboot the flag ICTIMESYNCFLAG_SYNC is included in the first time
 374  * message after the timesync channel is opened. Since the hv_utils module is
 375  * loaded after hv_vmbus, the first message is usually missed. This bit is
 376  * considered a hard request to discipline the clock.
 377  *
 378  * ICTIMESYNCFLAG_SAMPLE bit indicates a time sample from host. This is
 379  * typically used as a hint to the guest. The guest is under no obligation
 380  * to discipline the clock.
 381  */
 382 static inline void adj_guesttime(u64 hosttime, u64 reftime, u8 adj_flags)
 383 {
 384         unsigned long flags;
 385         u64 cur_reftime;
 386
 387         /*
 388          * Save the adjusted time sample from the host and the snapshot
 389          * of the current system time.
 390          */
 391         spin_lock_irqsave(&host_ts.lock, flags);
 392
 393         cur_reftime = hv_read_reference_counter();
 394         host_ts.host_time = hosttime;
 395         host_ts.ref_time = cur_reftime;
 396
 397         /*
 398          * TimeSync v4 messages contain reference time (guest's Hyper-V
 399          * clocksource read when the time sample was generated), we can
 400          * improve the precision by adding the delta between now and the
 401          * time of generation. For older protocols we set
 402          * reftime == cur_reftime on call.
 403          */
 404         host_ts.host_time += (cur_reftime - reftime);
 405
 406         spin_unlock_irqrestore(&host_ts.lock, flags);
 407
 408         /* Schedule work to do do_settimeofday64() */
 409         if ((adj_flags & ICTIMESYNCFLAG_SYNC) ||
 410             (timesync_implicit && hv_implicit_sync(host_ts.host_time)))
 411                 schedule_work(&adj_time_work);
 412 }
 413
 414 /*
 415  * Time Sync Channel message handler.
 416  */
 417 static void timesync_onchannelcallback(void *context)
 418 {
 419         struct vmbus_channel *channel = context;
 420         u32 recvlen;
 421         u64 requestid;
 422         struct icmsg_hdr *icmsghdrp;
 423         struct ictimesync_data *timedatap;
 424         struct ictimesync_ref_data *refdata;
 425         u8 *time_txf_buf = util_timesynch.recv_buffer;
 426
 427         /*
 428          * Drain the ring buffer and use the last packet to update
 429          * host_ts
 430          */
 431         while (1) {
 432                 int ret = vmbus_recvpacket(channel, time_txf_buf,
 433                                            HV_HYP_PAGE_SIZE, &recvlen,
 434                                            &requestid);
 435                 if (ret) {
 436                         pr_err_ratelimited("TimeSync IC pkt recv failed (Err: %d)\n",
 437                                            ret);
 438                         break;
 439                 }
 440
 441                 if (!recvlen)
 442                         break;
 443
 444                 /* Ensure recvlen is big enough to read header data */
 445                 if (recvlen < ICMSG_HDR) {
 446                         pr_err_ratelimited("Timesync request received. Packet length too small: %d\n",
 447                                            recvlen);
 448                         break;
 449                 }
 450
 451                 icmsghdrp = (struct icmsg_hdr *)&time_txf_buf[
 452                                 sizeof(struct vmbuspipe_hdr)];
 453
 454                 if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) {
 455                         if (vmbus_prep_negotiate_resp(icmsghdrp,
 456                                                 time_txf_buf, recvlen,
 457                                                 fw_versions, FW_VER_COUNT,
 458                                                 ts_versions, TS_VER_COUNT,
 459                                                 NULL, &ts_srv_version)) {
 460                                 pr_info("TimeSync IC version %d.%d\n",
 461                                         ts_srv_version >> 16,
 462                                         ts_srv_version & 0xFFFF);
 463                         }
 464                 } else if (icmsghdrp->icmsgtype == ICMSGTYPE_TIMESYNC) {
 465                         if (ts_srv_version > TS_VERSION_3) {
 466                                 /* Ensure recvlen is big enough to read ictimesync_ref_data */
 467                                 if (recvlen < ICMSG_HDR + sizeof(struct ictimesync_ref_data)) {
 468                                         pr_err_ratelimited("Invalid ictimesync ref data. Length too small: %u\n",
 469                                                            recvlen);
 470                                         break;
 471                                 }
 472                                 refdata = (struct ictimesync_ref_data *)&time_txf_buf[ICMSG_HDR];
 473
 474                                 adj_guesttime(refdata->parenttime,
 475                                                 refdata->vmreferencetime,
 476                                                 refdata->flags);
 477                         } else {
 478                                 /* Ensure recvlen is big enough to read ictimesync_data */
 479                                 if (recvlen < ICMSG_HDR + sizeof(struct ictimesync_data)) {
 480                                         pr_err_ratelimited("Invalid ictimesync data. Length too small: %u\n",
 481                                                            recvlen);
 482                                         break;
 483                                 }
 484                                 timedatap = (struct ictimesync_data *)&time_txf_buf[ICMSG_HDR];
 485
 486                                 adj_guesttime(timedatap->parenttime,
 487                                               hv_read_reference_counter(),
 488                                               timedatap->flags);
 489                         }
 490                 } else {
 491                         icmsghdrp->status = HV_E_FAIL;
 492                         pr_err_ratelimited("Timesync request received. Invalid msg type: %d\n",
 493                                            icmsghdrp->icmsgtype);
 494                 }
 495
 496                 icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION
 497                         | ICMSGHDRFLAG_RESPONSE;
 498
 499                 vmbus_sendpacket(channel, time_txf_buf,
 500                                  recvlen, requestid,
 501                                  VM_PKT_DATA_INBAND, 0);
 502         }
 503 }
 504
 505 /*
 506  * Heartbeat functionality.
 507  * Every two seconds, Hyper-V send us a heartbeat request message.
 508  * we respond to this message, and Hyper-V knows we are alive.
 509  */
 510 static void heartbeat_onchannelcallback(void *context)
 511 {
 512         struct vmbus_channel *channel = context;
 513         u32 recvlen;
 514         u64 requestid;
 515         struct icmsg_hdr *icmsghdrp;
 516         struct heartbeat_msg_data *heartbeat_msg;
 517         u8 *hbeat_txf_buf = util_heartbeat.recv_buffer;
 518
 519         while (1) {
 520
 521                 if (vmbus_recvpacket(channel, hbeat_txf_buf, HV_HYP_PAGE_SIZE,
 522                                      &recvlen, &requestid)) {
 523                         pr_err_ratelimited("Heartbeat request received. Could not read into hbeat txf buf\n");
 524                         return;
 525                 }
 526
 527                 if (!recvlen)
 528                         break;
 529
 530                 /* Ensure recvlen is big enough to read header data */
 531                 if (recvlen < ICMSG_HDR) {
 532                         pr_err_ratelimited("Heartbeat request received. Packet length too small: %d\n",
 533                                            recvlen);
 534                         break;
 535                 }
 536
 537                 icmsghdrp = (struct icmsg_hdr *)&hbeat_txf_buf[
 538                                 sizeof(struct vmbuspipe_hdr)];
 539
 540                 if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) {
 541                         if (vmbus_prep_negotiate_resp(icmsghdrp,
 542                                         hbeat_txf_buf, recvlen,
 543                                         fw_versions, FW_VER_COUNT,
 544                                         hb_versions, HB_VER_COUNT,
 545                                         NULL, &hb_srv_version)) {
 546
 547                                 pr_info("Heartbeat IC version %d.%d\n",
 548                                         hb_srv_version >> 16,
 549                                         hb_srv_version & 0xFFFF);
 550                         }
 551                 } else if (icmsghdrp->icmsgtype == ICMSGTYPE_HEARTBEAT) {
 552                         /*
 553                          * Ensure recvlen is big enough to read seq_num. Reserved area is not
 554                          * included in the check as the host may not fill it up entirely
 555                          */
 556                         if (recvlen < ICMSG_HDR + sizeof(u64)) {
 557                                 pr_err_ratelimited("Invalid heartbeat msg data. Length too small: %u\n",
 558                                                    recvlen);
 559                                 break;
 560                         }
 561                         heartbeat_msg = (struct heartbeat_msg_data *)&hbeat_txf_buf[ICMSG_HDR];
 562
 563                         heartbeat_msg->seq_num += 1;
 564                 } else {
 565                         icmsghdrp->status = HV_E_FAIL;
 566                         pr_err_ratelimited("Heartbeat request received. Invalid msg type: %d\n",
 567                                            icmsghdrp->icmsgtype);
 568                 }
 569
 570                 icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION
 571                         | ICMSGHDRFLAG_RESPONSE;
 572
 573                 vmbus_sendpacket(channel, hbeat_txf_buf,
 574                                  recvlen, requestid,
 575                                  VM_PKT_DATA_INBAND, 0);
 576         }
 577 }
 578
 579 #define HV_UTIL_RING_SEND_SIZE VMBUS_RING_SIZE(3 * HV_HYP_PAGE_SIZE)
 580 #define HV_UTIL_RING_RECV_SIZE VMBUS_RING_SIZE(3 * HV_HYP_PAGE_SIZE)
 581
 582 static int util_probe(struct hv_device *dev,
 583                         const struct hv_vmbus_device_id *dev_id)
 584 {
 585         struct hv_util_service *srv =
 586                 (struct hv_util_service *)dev_id->driver_data;
 587         int ret;
 588
 589         srv->recv_buffer = kmalloc(HV_HYP_PAGE_SIZE * 4, GFP_KERNEL);
 590         if (!srv->recv_buffer)
 591                 return -ENOMEM;
 592         srv->channel = dev->channel;
 593         if (srv->util_init) {
 594                 ret = srv->util_init(srv);
 595                 if (ret)
 596                         goto error1;
 597         }
 598
 599         /*
 600          * The set of services managed by the util driver are not performance
 601          * critical and do not need batched reading. Furthermore, some services
 602          * such as KVP can only handle one message from the host at a time.
 603          * Turn off batched reading for all util drivers before we open the
 604          * channel.
 605          */
 606         set_channel_read_mode(dev->channel, HV_CALL_DIRECT);
 607
 608         hv_set_drvdata(dev, srv);
 609
 610         ret = vmbus_open(dev->channel, HV_UTIL_RING_SEND_SIZE,
 611                          HV_UTIL_RING_RECV_SIZE, NULL, 0, srv->util_cb,
 612                          dev->channel);
 613         if (ret)
 614                 goto error;
 615
 616         if (srv->util_init_transport) {
 617                 ret = srv->util_init_transport();
 618                 if (ret) {
 619                         vmbus_close(dev->channel);
 620                         goto error;
 621                 }
 622         }
 623         return 0;
 624
 625 error:
 626         if (srv->util_deinit)
 627                 srv->util_deinit();
 628 error1:
 629         kfree(srv->recv_buffer);
 630         return ret;
 631 }
 632
 633 static void util_remove(struct hv_device *dev)
 634 {
 635         struct hv_util_service *srv = hv_get_drvdata(dev);
 636
 637         if (srv->util_deinit)
 638                 srv->util_deinit();
 639         vmbus_close(dev->channel);
 640         kfree(srv->recv_buffer);
 641 }
 642
 643 /*
 644  * When we're in util_suspend(), all the userspace processes have been frozen
 645  * (refer to hibernate() -> freeze_processes()). The userspace is thawed only
 646  * after the whole resume procedure, including util_resume(), finishes.
 647  */
 648 static int util_suspend(struct hv_device *dev)
 649 {
 650         struct hv_util_service *srv = hv_get_drvdata(dev);
 651         int ret = 0;
 652
 653         if (srv->util_pre_suspend) {
 654                 ret = srv->util_pre_suspend();
 655                 if (ret)
 656                         return ret;
 657         }
 658
 659         vmbus_close(dev->channel);
 660
 661         return 0;
 662 }
 663
 664 static int util_resume(struct hv_device *dev)
 665 {
 666         struct hv_util_service *srv = hv_get_drvdata(dev);
 667         int ret = 0;
 668
 669         if (srv->util_pre_resume) {
 670                 ret = srv->util_pre_resume();
 671                 if (ret)
 672                         return ret;
 673         }
 674
 675         ret = vmbus_open(dev->channel, HV_UTIL_RING_SEND_SIZE,
 676                          HV_UTIL_RING_RECV_SIZE, NULL, 0, srv->util_cb,
 677                          dev->channel);
 678         return ret;
 679 }
 680
 681 static const struct hv_vmbus_device_id id_table[] = {
 682         /* Shutdown guid */
 683         { HV_SHUTDOWN_GUID,
 684           .driver_data = (unsigned long)&util_shutdown
 685         },
 686         /* Time synch guid */
 687         { HV_TS_GUID,
 688           .driver_data = (unsigned long)&util_timesynch
 689         },
 690         /* Heartbeat guid */
 691         { HV_HEART_BEAT_GUID,
 692           .driver_data = (unsigned long)&util_heartbeat
 693         },
 694         /* KVP guid */
 695         { HV_KVP_GUID,
 696           .driver_data = (unsigned long)&util_kvp
 697         },
 698         /* VSS GUID */
 699         { HV_VSS_GUID,
 700           .driver_data = (unsigned long)&util_vss
 701         },
 702         { },
 703 };
 704
 705 MODULE_DEVICE_TABLE(vmbus, id_table);
 706
 707 /* The one and only one */
 708 static  struct hv_driver util_drv = {
 709         .name = "hv_utils",
 710         .id_table = id_table,
 711         .probe =  util_probe,
 712         .remove =  util_remove,
 713         .suspend = util_suspend,
 714         .resume =  util_resume,
 715         .driver = {
 716                 .probe_type = PROBE_PREFER_ASYNCHRONOUS,
 717         },
 718 };
 719
 720 static int hv_ptp_enable(struct ptp_clock_info *info,
 721                          struct ptp_clock_request *request, int on)
 722 {
 723         return -EOPNOTSUPP;
 724 }
 725
 726 static int hv_ptp_settime(struct ptp_clock_info *p, const struct timespec64 *ts)
 727 {
 728         return -EOPNOTSUPP;
 729 }
 730
 731 static int hv_ptp_adjfine(struct ptp_clock_info *ptp, long delta)
 732 {
 733         return -EOPNOTSUPP;
 734 }
 735 static int hv_ptp_adjtime(struct ptp_clock_info *ptp, s64 delta)
 736 {
 737         return -EOPNOTSUPP;
 738 }
 739
 740 static int hv_ptp_gettime(struct ptp_clock_info *info, struct timespec64 *ts)
 741 {
 742         return hv_get_adj_host_time(ts);
 743 }
 744
 745 static struct ptp_clock_info ptp_hyperv_info = {
 746         .name           = "hyperv",
 747         .enable         = hv_ptp_enable,
 748         .adjtime        = hv_ptp_adjtime,
 749         .adjfine        = hv_ptp_adjfine,
 750         .gettime64      = hv_ptp_gettime,
 751         .settime64      = hv_ptp_settime,
 752         .owner          = THIS_MODULE,
 753 };
 754
 755 static struct ptp_clock *hv_ptp_clock;
 756
 757 static int hv_timesync_init(struct hv_util_service *srv)
 758 {
 759         spin_lock_init(&host_ts.lock);
 760
 761         INIT_WORK(&adj_time_work, hv_set_host_time);
 762
 763         /*
 764          * ptp_clock_register() returns NULL when CONFIG_PTP_1588_CLOCK is
 765          * disabled but the driver is still useful without the PTP device
 766          * as it still handles the ICTIMESYNCFLAG_SYNC case.
 767          */
 768         hv_ptp_clock = ptp_clock_register(&ptp_hyperv_info, NULL);
 769         if (IS_ERR_OR_NULL(hv_ptp_clock)) {
 770                 pr_err("cannot register PTP clock: %d\n",
 771                        PTR_ERR_OR_ZERO(hv_ptp_clock));
 772                 hv_ptp_clock = NULL;
 773         }
 774
 775         return 0;
 776 }
 777
 778 static void hv_timesync_cancel_work(void)
 779 {
 780         cancel_work_sync(&adj_time_work);
 781 }
 782
 783 static int hv_timesync_pre_suspend(void)
 784 {
 785         hv_timesync_cancel_work();
 786         return 0;
 787 }
 788
 789 static void hv_timesync_deinit(void)
 790 {
 791         if (hv_ptp_clock)
 792                 ptp_clock_unregister(hv_ptp_clock);
 793
 794         hv_timesync_cancel_work();
 795 }
 796
 797 static int __init init_hyperv_utils(void)
 798 {
 799         pr_info("Registering HyperV Utility Driver\n");
 800
 801         return vmbus_driver_register(&util_drv);
 802 }
 803
 804 static void exit_hyperv_utils(void)
 805 {
 806         pr_info("De-Registered HyperV Utility Driver\n");
 807
 808         vmbus_driver_unregister(&util_drv);
 809 }
 810
 811 module_init(init_hyperv_utils);
 812 module_exit(exit_hyperv_utils);
 813
 814 MODULE_DESCRIPTION("Hyper-V Utilities");
 815 MODULE_LICENSE("GPL");