drivers/hv/hv_util.c

   1 /*
   2  * Copyright (c) 2010, 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/init.h>
  25 #include <linux/module.h>
  26 #include <linux/slab.h>
  27 #include <linux/sysctl.h>
  28 #include <linux/reboot.h>
  29 #include <linux/hyperv.h>
  30 #include <linux/clockchips.h>
  31 #include <linux/ptp_clock_kernel.h>
  32 #include <asm/mshyperv.h>
  33
  34 #include "hyperv_vmbus.h"
  35
  36 #define SD_MAJOR        3
  37 #define SD_MINOR        0
  38 #define SD_VERSION      (SD_MAJOR << 16 | SD_MINOR)
  39
  40 #define SD_MAJOR_1      1
  41 #define SD_VERSION_1    (SD_MAJOR_1 << 16 | SD_MINOR)
  42
  43 #define TS_MAJOR        4
  44 #define TS_MINOR        0
  45 #define TS_VERSION      (TS_MAJOR << 16 | TS_MINOR)
  46
  47 #define TS_MAJOR_1      1
  48 #define TS_VERSION_1    (TS_MAJOR_1 << 16 | TS_MINOR)
  49
  50 #define TS_MAJOR_3      3
  51 #define TS_VERSION_3    (TS_MAJOR_3 << 16 | TS_MINOR)
  52
  53 #define HB_MAJOR        3
  54 #define HB_MINOR        0
  55 #define HB_VERSION      (HB_MAJOR << 16 | HB_MINOR)
  56
  57 #define HB_MAJOR_1      1
  58 #define HB_VERSION_1    (HB_MAJOR_1 << 16 | HB_MINOR)
  59
  60 static int sd_srv_version;
  61 static int ts_srv_version;
  62 static int hb_srv_version;
  63
  64 #define SD_VER_COUNT 2
  65 static const int sd_versions[] = {
  66         SD_VERSION,
  67         SD_VERSION_1
  68 };
  69
  70 #define TS_VER_COUNT 3
  71 static const int ts_versions[] = {
  72         TS_VERSION,
  73         TS_VERSION_3,
  74         TS_VERSION_1
  75 };
  76
  77 #define HB_VER_COUNT 2
  78 static const int hb_versions[] = {
  79         HB_VERSION,
  80         HB_VERSION_1
  81 };
  82
  83 #define FW_VER_COUNT 2
  84 static const int fw_versions[] = {
  85         UTIL_FW_VERSION,
  86         UTIL_WS2K8_FW_VERSION
  87 };
  88
  89 static void shutdown_onchannelcallback(void *context);
  90 static struct hv_util_service util_shutdown = {
  91         .util_cb = shutdown_onchannelcallback,
  92 };
  93
  94 static int hv_timesync_init(struct hv_util_service *srv);
  95 static void hv_timesync_deinit(void);
  96
  97 static void timesync_onchannelcallback(void *context);
  98 static struct hv_util_service util_timesynch = {
  99         .util_cb = timesync_onchannelcallback,
 100         .util_init = hv_timesync_init,
 101         .util_deinit = hv_timesync_deinit,
 102 };
 103
 104 static void heartbeat_onchannelcallback(void *context);
 105 static struct hv_util_service util_heartbeat = {
 106         .util_cb = heartbeat_onchannelcallback,
 107 };
 108
 109 static struct hv_util_service util_kvp = {
 110         .util_cb = hv_kvp_onchannelcallback,
 111         .util_init = hv_kvp_init,
 112         .util_deinit = hv_kvp_deinit,
 113 };
 114
 115 static struct hv_util_service util_vss = {
 116         .util_cb = hv_vss_onchannelcallback,
 117         .util_init = hv_vss_init,
 118         .util_deinit = hv_vss_deinit,
 119 };
 120
 121 static struct hv_util_service util_fcopy = {
 122         .util_cb = hv_fcopy_onchannelcallback,
 123         .util_init = hv_fcopy_init,
 124         .util_deinit = hv_fcopy_deinit,
 125 };
 126
 127 static void perform_shutdown(struct work_struct *dummy)
 128 {
 129         orderly_poweroff(true);
 130 }
 131
 132 /*
 133  * Perform the shutdown operation in a thread context.
 134  */
 135 static DECLARE_WORK(shutdown_work, perform_shutdown);
 136
 137 static void shutdown_onchannelcallback(void *context)
 138 {
 139         struct vmbus_channel *channel = context;
 140         u32 recvlen;
 141         u64 requestid;
 142         bool execute_shutdown = false;
 143         u8  *shut_txf_buf = util_shutdown.recv_buffer;
 144
 145         struct shutdown_msg_data *shutdown_msg;
 146
 147         struct icmsg_hdr *icmsghdrp;
 148
 149         vmbus_recvpacket(channel, shut_txf_buf,
 150                          PAGE_SIZE, &recvlen, &requestid);
 151
 152         if (recvlen > 0) {
 153                 icmsghdrp = (struct icmsg_hdr *)&shut_txf_buf[
 154                         sizeof(struct vmbuspipe_hdr)];
 155
 156                 if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) {
 157                         if (vmbus_prep_negotiate_resp(icmsghdrp, shut_txf_buf,
 158                                         fw_versions, FW_VER_COUNT,
 159                                         sd_versions, SD_VER_COUNT,
 160                                         NULL, &sd_srv_version)) {
 161                                 pr_info("Shutdown IC version %d.%d\n",
 162                                         sd_srv_version >> 16,
 163                                         sd_srv_version & 0xFFFF);
 164                         }
 165                 } else {
 166                         shutdown_msg =
 167                                 (struct shutdown_msg_data *)&shut_txf_buf[
 168                                         sizeof(struct vmbuspipe_hdr) +
 169                                         sizeof(struct icmsg_hdr)];
 170
 171                         switch (shutdown_msg->flags) {
 172                         case 0:
 173                         case 1:
 174                                 icmsghdrp->status = HV_S_OK;
 175                                 execute_shutdown = true;
 176
 177                                 pr_info("Shutdown request received -"
 178                                             " graceful shutdown initiated\n");
 179                                 break;
 180                         default:
 181                                 icmsghdrp->status = HV_E_FAIL;
 182                                 execute_shutdown = false;
 183
 184                                 pr_info("Shutdown request received -"
 185                                             " Invalid request\n");
 186                                 break;
 187                         }
 188                 }
 189
 190                 icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION
 191                         | ICMSGHDRFLAG_RESPONSE;
 192
 193                 vmbus_sendpacket(channel, shut_txf_buf,
 194                                        recvlen, requestid,
 195                                        VM_PKT_DATA_INBAND, 0);
 196         }
 197
 198         if (execute_shutdown == true)
 199                 schedule_work(&shutdown_work);
 200 }
 201
 202 /*
 203  * Set the host time in a process context.
 204  */
 205 static struct work_struct adj_time_work;
 206
 207 /*
 208  * The last time sample, received from the host. PTP device responds to
 209  * requests by using this data and the current partition-wide time reference
 210  * count.
 211  */
 212 static struct {
 213         u64                             host_time;
 214         u64                             ref_time;
 215         spinlock_t                      lock;
 216 } host_ts;
 217
 218 static struct timespec64 hv_get_adj_host_time(void)
 219 {
 220         struct timespec64 ts;
 221         u64 newtime, reftime;
 222         unsigned long flags;
 223
 224         spin_lock_irqsave(&host_ts.lock, flags);
 225         reftime = hyperv_cs->read(hyperv_cs);
 226         newtime = host_ts.host_time + (reftime - host_ts.ref_time);
 227         ts = ns_to_timespec64((newtime - WLTIMEDELTA) * 100);
 228         spin_unlock_irqrestore(&host_ts.lock, flags);
 229
 230         return ts;
 231 }
 232
 233 static void hv_set_host_time(struct work_struct *work)
 234 {
 235         struct timespec64 ts = hv_get_adj_host_time();
 236
 237         do_settimeofday64(&ts);
 238 }
 239
 240 /*
 241  * Synchronize time with host after reboot, restore, etc.
 242  *
 243  * ICTIMESYNCFLAG_SYNC flag bit indicates reboot, restore events of the VM.
 244  * After reboot the flag ICTIMESYNCFLAG_SYNC is included in the first time
 245  * message after the timesync channel is opened. Since the hv_utils module is
 246  * loaded after hv_vmbus, the first message is usually missed. This bit is
 247  * considered a hard request to discipline the clock.
 248  *
 249  * ICTIMESYNCFLAG_SAMPLE bit indicates a time sample from host. This is
 250  * typically used as a hint to the guest. The guest is under no obligation
 251  * to discipline the clock.
 252  */
 253 static inline void adj_guesttime(u64 hosttime, u64 reftime, u8 adj_flags)
 254 {
 255         unsigned long flags;
 256         u64 cur_reftime;
 257
 258         /*
 259          * Save the adjusted time sample from the host and the snapshot
 260          * of the current system time.
 261          */
 262         spin_lock_irqsave(&host_ts.lock, flags);
 263
 264         cur_reftime = hyperv_cs->read(hyperv_cs);
 265         host_ts.host_time = hosttime;
 266         host_ts.ref_time = cur_reftime;
 267
 268         /*
 269          * TimeSync v4 messages contain reference time (guest's Hyper-V
 270          * clocksource read when the time sample was generated), we can
 271          * improve the precision by adding the delta between now and the
 272          * time of generation. For older protocols we set
 273          * reftime == cur_reftime on call.
 274          */
 275         host_ts.host_time += (cur_reftime - reftime);
 276
 277         spin_unlock_irqrestore(&host_ts.lock, flags);
 278
 279         /* Schedule work to do do_settimeofday64() */
 280         if (adj_flags & ICTIMESYNCFLAG_SYNC)
 281                 schedule_work(&adj_time_work);
 282 }
 283
 284 /*
 285  * Time Sync Channel message handler.
 286  */
 287 static void timesync_onchannelcallback(void *context)
 288 {
 289         struct vmbus_channel *channel = context;
 290         u32 recvlen;
 291         u64 requestid;
 292         struct icmsg_hdr *icmsghdrp;
 293         struct ictimesync_data *timedatap;
 294         struct ictimesync_ref_data *refdata;
 295         u8 *time_txf_buf = util_timesynch.recv_buffer;
 296
 297         vmbus_recvpacket(channel, time_txf_buf,
 298                          PAGE_SIZE, &recvlen, &requestid);
 299
 300         if (recvlen > 0) {
 301                 icmsghdrp = (struct icmsg_hdr *)&time_txf_buf[
 302                                 sizeof(struct vmbuspipe_hdr)];
 303
 304                 if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) {
 305                         if (vmbus_prep_negotiate_resp(icmsghdrp, time_txf_buf,
 306                                                 fw_versions, FW_VER_COUNT,
 307                                                 ts_versions, TS_VER_COUNT,
 308                                                 NULL, &ts_srv_version)) {
 309                                 pr_info("TimeSync IC version %d.%d\n",
 310                                         ts_srv_version >> 16,
 311                                         ts_srv_version & 0xFFFF);
 312                         }
 313                 } else {
 314                         if (ts_srv_version > TS_VERSION_3) {
 315                                 refdata = (struct ictimesync_ref_data *)
 316                                         &time_txf_buf[
 317                                         sizeof(struct vmbuspipe_hdr) +
 318                                         sizeof(struct icmsg_hdr)];
 319
 320                                 adj_guesttime(refdata->parenttime,
 321                                                 refdata->vmreferencetime,
 322                                                 refdata->flags);
 323                         } else {
 324                                 timedatap = (struct ictimesync_data *)
 325                                         &time_txf_buf[
 326                                         sizeof(struct vmbuspipe_hdr) +
 327                                         sizeof(struct icmsg_hdr)];
 328                                 adj_guesttime(timedatap->parenttime,
 329                                               hyperv_cs->read(hyperv_cs),
 330                                               timedatap->flags);
 331                         }
 332                 }
 333
 334                 icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION
 335                         | ICMSGHDRFLAG_RESPONSE;
 336
 337                 vmbus_sendpacket(channel, time_txf_buf,
 338                                 recvlen, requestid,
 339                                 VM_PKT_DATA_INBAND, 0);
 340         }
 341 }
 342
 343 /*
 344  * Heartbeat functionality.
 345  * Every two seconds, Hyper-V send us a heartbeat request message.
 346  * we respond to this message, and Hyper-V knows we are alive.
 347  */
 348 static void heartbeat_onchannelcallback(void *context)
 349 {
 350         struct vmbus_channel *channel = context;
 351         u32 recvlen;
 352         u64 requestid;
 353         struct icmsg_hdr *icmsghdrp;
 354         struct heartbeat_msg_data *heartbeat_msg;
 355         u8 *hbeat_txf_buf = util_heartbeat.recv_buffer;
 356
 357         while (1) {
 358
 359                 vmbus_recvpacket(channel, hbeat_txf_buf,
 360                                  PAGE_SIZE, &recvlen, &requestid);
 361
 362                 if (!recvlen)
 363                         break;
 364
 365                 icmsghdrp = (struct icmsg_hdr *)&hbeat_txf_buf[
 366                                 sizeof(struct vmbuspipe_hdr)];
 367
 368                 if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) {
 369                         if (vmbus_prep_negotiate_resp(icmsghdrp,
 370                                         hbeat_txf_buf,
 371                                         fw_versions, FW_VER_COUNT,
 372                                         hb_versions, HB_VER_COUNT,
 373                                         NULL, &hb_srv_version)) {
 374
 375                                 pr_info("Heartbeat IC version %d.%d\n",
 376                                         hb_srv_version >> 16,
 377                                         hb_srv_version & 0xFFFF);
 378                         }
 379                 } else {
 380                         heartbeat_msg =
 381                                 (struct heartbeat_msg_data *)&hbeat_txf_buf[
 382                                         sizeof(struct vmbuspipe_hdr) +
 383                                         sizeof(struct icmsg_hdr)];
 384
 385                         heartbeat_msg->seq_num += 1;
 386                 }
 387
 388                 icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION
 389                         | ICMSGHDRFLAG_RESPONSE;
 390
 391                 vmbus_sendpacket(channel, hbeat_txf_buf,
 392                                        recvlen, requestid,
 393                                        VM_PKT_DATA_INBAND, 0);
 394         }
 395 }
 396
 397 static int util_probe(struct hv_device *dev,
 398                         const struct hv_vmbus_device_id *dev_id)
 399 {
 400         struct hv_util_service *srv =
 401                 (struct hv_util_service *)dev_id->driver_data;
 402         int ret;
 403
 404         srv->recv_buffer = kmalloc(PAGE_SIZE * 4, GFP_KERNEL);
 405         if (!srv->recv_buffer)
 406                 return -ENOMEM;
 407         srv->channel = dev->channel;
 408         if (srv->util_init) {
 409                 ret = srv->util_init(srv);
 410                 if (ret) {
 411                         ret = -ENODEV;
 412                         goto error1;
 413                 }
 414         }
 415
 416         /*
 417          * The set of services managed by the util driver are not performance
 418          * critical and do not need batched reading. Furthermore, some services
 419          * such as KVP can only handle one message from the host at a time.
 420          * Turn off batched reading for all util drivers before we open the
 421          * channel.
 422          */
 423         set_channel_read_mode(dev->channel, HV_CALL_DIRECT);
 424
 425         hv_set_drvdata(dev, srv);
 426
 427         ret = vmbus_open(dev->channel, 4 * PAGE_SIZE, 4 * PAGE_SIZE, NULL, 0,
 428                         srv->util_cb, dev->channel);
 429         if (ret)
 430                 goto error;
 431
 432         return 0;
 433
 434 error:
 435         if (srv->util_deinit)
 436                 srv->util_deinit();
 437 error1:
 438         kfree(srv->recv_buffer);
 439         return ret;
 440 }
 441
 442 static int util_remove(struct hv_device *dev)
 443 {
 444         struct hv_util_service *srv = hv_get_drvdata(dev);
 445
 446         if (srv->util_deinit)
 447                 srv->util_deinit();
 448         vmbus_close(dev->channel);
 449         kfree(srv->recv_buffer);
 450
 451         return 0;
 452 }
 453
 454 static const struct hv_vmbus_device_id id_table[] = {
 455         /* Shutdown guid */
 456         { HV_SHUTDOWN_GUID,
 457           .driver_data = (unsigned long)&util_shutdown
 458         },
 459         /* Time synch guid */
 460         { HV_TS_GUID,
 461           .driver_data = (unsigned long)&util_timesynch
 462         },
 463         /* Heartbeat guid */
 464         { HV_HEART_BEAT_GUID,
 465           .driver_data = (unsigned long)&util_heartbeat
 466         },
 467         /* KVP guid */
 468         { HV_KVP_GUID,
 469           .driver_data = (unsigned long)&util_kvp
 470         },
 471         /* VSS GUID */
 472         { HV_VSS_GUID,
 473           .driver_data = (unsigned long)&util_vss
 474         },
 475         /* File copy GUID */
 476         { HV_FCOPY_GUID,
 477           .driver_data = (unsigned long)&util_fcopy
 478         },
 479         { },
 480 };
 481
 482 MODULE_DEVICE_TABLE(vmbus, id_table);
 483
 484 /* The one and only one */
 485 static  struct hv_driver util_drv = {
 486         .name = "hv_util",
 487         .id_table = id_table,
 488         .probe =  util_probe,
 489         .remove =  util_remove,
 490         .driver = {
 491                 .probe_type = PROBE_PREFER_ASYNCHRONOUS,
 492         },
 493 };
 494
 495 static int hv_ptp_enable(struct ptp_clock_info *info,
 496                          struct ptp_clock_request *request, int on)
 497 {
 498         return -EOPNOTSUPP;
 499 }
 500
 501 static int hv_ptp_settime(struct ptp_clock_info *p, const struct timespec64 *ts)
 502 {
 503         return -EOPNOTSUPP;
 504 }
 505
 506 static int hv_ptp_adjfreq(struct ptp_clock_info *ptp, s32 delta)
 507 {
 508         return -EOPNOTSUPP;
 509 }
 510 static int hv_ptp_adjtime(struct ptp_clock_info *ptp, s64 delta)
 511 {
 512         return -EOPNOTSUPP;
 513 }
 514
 515 static int hv_ptp_gettime(struct ptp_clock_info *info, struct timespec64 *ts)
 516 {
 517         *ts = hv_get_adj_host_time();
 518
 519         return 0;
 520 }
 521
 522 static struct ptp_clock_info ptp_hyperv_info = {
 523         .name           = "hyperv",
 524         .enable         = hv_ptp_enable,
 525         .adjtime        = hv_ptp_adjtime,
 526         .adjfreq        = hv_ptp_adjfreq,
 527         .gettime64      = hv_ptp_gettime,
 528         .settime64      = hv_ptp_settime,
 529         .owner          = THIS_MODULE,
 530 };
 531
 532 static struct ptp_clock *hv_ptp_clock;
 533
 534 static int hv_timesync_init(struct hv_util_service *srv)
 535 {
 536         /* TimeSync requires Hyper-V clocksource. */
 537         if (!hyperv_cs)
 538                 return -ENODEV;
 539
 540         spin_lock_init(&host_ts.lock);
 541
 542         INIT_WORK(&adj_time_work, hv_set_host_time);
 543
 544         /*
 545          * ptp_clock_register() returns NULL when CONFIG_PTP_1588_CLOCK is
 546          * disabled but the driver is still useful without the PTP device
 547          * as it still handles the ICTIMESYNCFLAG_SYNC case.
 548          */
 549         hv_ptp_clock = ptp_clock_register(&ptp_hyperv_info, NULL);
 550         if (IS_ERR_OR_NULL(hv_ptp_clock)) {
 551                 pr_err("cannot register PTP clock: %ld\n",
 552                        PTR_ERR(hv_ptp_clock));
 553                 hv_ptp_clock = NULL;
 554         }
 555
 556         return 0;
 557 }
 558
 559 static void hv_timesync_deinit(void)
 560 {
 561         if (hv_ptp_clock)
 562                 ptp_clock_unregister(hv_ptp_clock);
 563         cancel_work_sync(&adj_time_work);
 564 }
 565
 566 static int __init init_hyperv_utils(void)
 567 {
 568         pr_info("Registering HyperV Utility Driver\n");
 569
 570         return vmbus_driver_register(&util_drv);
 571 }
 572
 573 static void exit_hyperv_utils(void)
 574 {
 575         pr_info("De-Registered HyperV Utility Driver\n");
 576
 577         vmbus_driver_unregister(&util_drv);
 578 }
 579
 580 module_init(init_hyperv_utils);
 581 module_exit(exit_hyperv_utils);
 582
 583 MODULE_DESCRIPTION("Hyper-V Utilities");
 584 MODULE_LICENSE("GPL");