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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (c) 2010, Microsoft Corporation.
4 *
5 * Authors:
6 * Haiyang Zhang <haiyangz@microsoft.com>
7 * Hank Janssen <hjanssen@microsoft.com>
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 <clocksource/hyperv_timer.h>
21#include <asm/mshyperv.h>
22
23#include "hyperv_vmbus.h"
24
25#define SD_MAJOR 3
26#define SD_MINOR 0
27#define SD_MINOR_1 1
28#define SD_MINOR_2 2
29#define SD_VERSION_3_1 (SD_MAJOR << 16 | SD_MINOR_1)
30#define SD_VERSION_3_2 (SD_MAJOR << 16 | SD_MINOR_2)
31#define SD_VERSION (SD_MAJOR << 16 | SD_MINOR)
32
33#define SD_MAJOR_1 1
34#define SD_VERSION_1 (SD_MAJOR_1 << 16 | SD_MINOR)
35
36#define TS_MAJOR 4
37#define TS_MINOR 0
38#define TS_VERSION (TS_MAJOR << 16 | TS_MINOR)
39
40#define TS_MAJOR_1 1
41#define TS_VERSION_1 (TS_MAJOR_1 << 16 | TS_MINOR)
42
43#define TS_MAJOR_3 3
44#define TS_VERSION_3 (TS_MAJOR_3 << 16 | TS_MINOR)
45
46#define HB_MAJOR 3
47#define HB_MINOR 0
48#define HB_VERSION (HB_MAJOR << 16 | HB_MINOR)
49
50#define HB_MAJOR_1 1
51#define HB_VERSION_1 (HB_MAJOR_1 << 16 | HB_MINOR)
52
53static int sd_srv_version;
54static int ts_srv_version;
55static int hb_srv_version;
56
57#define SD_VER_COUNT 4
58static const int sd_versions[] = {
59 SD_VERSION_3_2,
60 SD_VERSION_3_1,
61 SD_VERSION,
62 SD_VERSION_1
63};
64
65#define TS_VER_COUNT 3
66static const int ts_versions[] = {
67 TS_VERSION,
68 TS_VERSION_3,
69 TS_VERSION_1
70};
71
72#define HB_VER_COUNT 2
73static const int hb_versions[] = {
74 HB_VERSION,
75 HB_VERSION_1
76};
77
78#define FW_VER_COUNT 2
79static const int fw_versions[] = {
80 UTIL_FW_VERSION,
81 UTIL_WS2K8_FW_VERSION
82};
83
84/*
85 * Send the "hibernate" udev event in a thread context.
86 */
87struct hibernate_work_context {
88 struct work_struct work;
89 struct hv_device *dev;
90};
91
92static struct hibernate_work_context hibernate_context;
93static bool hibernation_supported;
94
95static void send_hibernate_uevent(struct work_struct *work)
96{
97 char *uevent_env[2] = { "EVENT=hibernate", NULL };
98 struct hibernate_work_context *ctx;
99
100 ctx = container_of(work, struct hibernate_work_context, work);
101
102 kobject_uevent_env(&ctx->dev->device.kobj, KOBJ_CHANGE, uevent_env);
103
104 pr_info("Sent hibernation uevent\n");
105}
106
107static int hv_shutdown_init(struct hv_util_service *srv)
108{
109 struct vmbus_channel *channel = srv->channel;
110
111 INIT_WORK(&hibernate_context.work, send_hibernate_uevent);
112 hibernate_context.dev = channel->device_obj;
113
114 hibernation_supported = hv_is_hibernation_supported();
115
116 return 0;
117}
118
119static void shutdown_onchannelcallback(void *context);
120static struct hv_util_service util_shutdown = {
121 .util_cb = shutdown_onchannelcallback,
122 .util_init = hv_shutdown_init,
123};
124
125static int hv_timesync_init(struct hv_util_service *srv);
126static int hv_timesync_pre_suspend(void);
127static void hv_timesync_deinit(void);
128
129static void timesync_onchannelcallback(void *context);
130static struct hv_util_service util_timesynch = {
131 .util_cb = timesync_onchannelcallback,
132 .util_init = hv_timesync_init,
133 .util_pre_suspend = hv_timesync_pre_suspend,
134 .util_deinit = hv_timesync_deinit,
135};
136
137static void heartbeat_onchannelcallback(void *context);
138static struct hv_util_service util_heartbeat = {
139 .util_cb = heartbeat_onchannelcallback,
140};
141
142static struct hv_util_service util_kvp = {
143 .util_cb = hv_kvp_onchannelcallback,
144 .util_init = hv_kvp_init,
145 .util_pre_suspend = hv_kvp_pre_suspend,
146 .util_pre_resume = hv_kvp_pre_resume,
147 .util_deinit = hv_kvp_deinit,
148};
149
150static struct hv_util_service util_vss = {
151 .util_cb = hv_vss_onchannelcallback,
152 .util_init = hv_vss_init,
153 .util_pre_suspend = hv_vss_pre_suspend,
154 .util_pre_resume = hv_vss_pre_resume,
155 .util_deinit = hv_vss_deinit,
156};
157
158static struct hv_util_service util_fcopy = {
159 .util_cb = hv_fcopy_onchannelcallback,
160 .util_init = hv_fcopy_init,
161 .util_pre_suspend = hv_fcopy_pre_suspend,
162 .util_pre_resume = hv_fcopy_pre_resume,
163 .util_deinit = hv_fcopy_deinit,
164};
165
166static void perform_shutdown(struct work_struct *dummy)
167{
168 orderly_poweroff(true);
169}
170
171static void perform_restart(struct work_struct *dummy)
172{
173 orderly_reboot();
174}
175
176/*
177 * Perform the shutdown operation in a thread context.
178 */
179static DECLARE_WORK(shutdown_work, perform_shutdown);
180
181/*
182 * Perform the restart operation in a thread context.
183 */
184static DECLARE_WORK(restart_work, perform_restart);
185
186static void shutdown_onchannelcallback(void *context)
187{
188 struct vmbus_channel *channel = context;
189 struct work_struct *work = NULL;
190 u32 recvlen;
191 u64 requestid;
192 u8 *shut_txf_buf = util_shutdown.recv_buffer;
193
194 struct shutdown_msg_data *shutdown_msg;
195
196 struct icmsg_hdr *icmsghdrp;
197
198 vmbus_recvpacket(channel, shut_txf_buf,
199 HV_HYP_PAGE_SIZE, &recvlen, &requestid);
200
201 if (recvlen > 0) {
202 icmsghdrp = (struct icmsg_hdr *)&shut_txf_buf[
203 sizeof(struct vmbuspipe_hdr)];
204
205 if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) {
206 if (vmbus_prep_negotiate_resp(icmsghdrp, shut_txf_buf,
207 fw_versions, FW_VER_COUNT,
208 sd_versions, SD_VER_COUNT,
209 NULL, &sd_srv_version)) {
210 pr_info("Shutdown IC version %d.%d\n",
211 sd_srv_version >> 16,
212 sd_srv_version & 0xFFFF);
213 }
214 } else {
215 shutdown_msg =
216 (struct shutdown_msg_data *)&shut_txf_buf[
217 sizeof(struct vmbuspipe_hdr) +
218 sizeof(struct icmsg_hdr)];
219
220 /*
221 * shutdown_msg->flags can be 0(shut down), 2(reboot),
222 * or 4(hibernate). It may bitwise-OR 1, which means
223 * performing the request by force. Linux always tries
224 * to perform the request by force.
225 */
226 switch (shutdown_msg->flags) {
227 case 0:
228 case 1:
229 icmsghdrp->status = HV_S_OK;
230 work = &shutdown_work;
231 pr_info("Shutdown request received -"
232 " graceful shutdown initiated\n");
233 break;
234 case 2:
235 case 3:
236 icmsghdrp->status = HV_S_OK;
237 work = &restart_work;
238 pr_info("Restart request received -"
239 " graceful restart initiated\n");
240 break;
241 case 4:
242 case 5:
243 pr_info("Hibernation request received\n");
244 icmsghdrp->status = hibernation_supported ?
245 HV_S_OK : HV_E_FAIL;
246 if (hibernation_supported)
247 work = &hibernate_context.work;
248 break;
249 default:
250 icmsghdrp->status = HV_E_FAIL;
251 pr_info("Shutdown request received -"
252 " Invalid request\n");
253 break;
254 }
255 }
256
257 icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION
258 | ICMSGHDRFLAG_RESPONSE;
259
260 vmbus_sendpacket(channel, shut_txf_buf,
261 recvlen, requestid,
262 VM_PKT_DATA_INBAND, 0);
263 }
264
265 if (work)
266 schedule_work(work);
267}
268
269/*
270 * Set the host time in a process context.
271 */
272static struct work_struct adj_time_work;
273
274/*
275 * The last time sample, received from the host. PTP device responds to
276 * requests by using this data and the current partition-wide time reference
277 * count.
278 */
279static struct {
280 u64 host_time;
281 u64 ref_time;
282 spinlock_t lock;
283} host_ts;
284
285static inline u64 reftime_to_ns(u64 reftime)
286{
287 return (reftime - WLTIMEDELTA) * 100;
288}
289
290/*
291 * Hard coded threshold for host timesync delay: 600 seconds
292 */
293static const u64 HOST_TIMESYNC_DELAY_THRESH = 600 * (u64)NSEC_PER_SEC;
294
295static int hv_get_adj_host_time(struct timespec64 *ts)
296{
297 u64 newtime, reftime, timediff_adj;
298 unsigned long flags;
299 int ret = 0;
300
301 spin_lock_irqsave(&host_ts.lock, flags);
302 reftime = hv_read_reference_counter();
303
304 /*
305 * We need to let the caller know that last update from host
306 * is older than the max allowable threshold. clock_gettime()
307 * and PTP ioctl do not have a documented error that we could
308 * return for this specific case. Use ESTALE to report this.
309 */
310 timediff_adj = reftime - host_ts.ref_time;
311 if (timediff_adj * 100 > HOST_TIMESYNC_DELAY_THRESH) {
312 pr_warn_once("TIMESYNC IC: Stale time stamp, %llu nsecs old\n",
313 (timediff_adj * 100));
314 ret = -ESTALE;
315 }
316
317 newtime = host_ts.host_time + timediff_adj;
318 *ts = ns_to_timespec64(reftime_to_ns(newtime));
319 spin_unlock_irqrestore(&host_ts.lock, flags);
320
321 return ret;
322}
323
324static void hv_set_host_time(struct work_struct *work)
325{
326
327 struct timespec64 ts;
328
329 if (!hv_get_adj_host_time(&ts))
330 do_settimeofday64(&ts);
331}
332
333/*
334 * Synchronize time with host after reboot, restore, etc.
335 *
336 * ICTIMESYNCFLAG_SYNC flag bit indicates reboot, restore events of the VM.
337 * After reboot the flag ICTIMESYNCFLAG_SYNC is included in the first time
338 * message after the timesync channel is opened. Since the hv_utils module is
339 * loaded after hv_vmbus, the first message is usually missed. This bit is
340 * considered a hard request to discipline the clock.
341 *
342 * ICTIMESYNCFLAG_SAMPLE bit indicates a time sample from host. This is
343 * typically used as a hint to the guest. The guest is under no obligation
344 * to discipline the clock.
345 */
346static inline void adj_guesttime(u64 hosttime, u64 reftime, u8 adj_flags)
347{
348 unsigned long flags;
349 u64 cur_reftime;
350
351 /*
352 * Save the adjusted time sample from the host and the snapshot
353 * of the current system time.
354 */
355 spin_lock_irqsave(&host_ts.lock, flags);
356
357 cur_reftime = hv_read_reference_counter();
358 host_ts.host_time = hosttime;
359 host_ts.ref_time = cur_reftime;
360
361 /*
362 * TimeSync v4 messages contain reference time (guest's Hyper-V
363 * clocksource read when the time sample was generated), we can
364 * improve the precision by adding the delta between now and the
365 * time of generation. For older protocols we set
366 * reftime == cur_reftime on call.
367 */
368 host_ts.host_time += (cur_reftime - reftime);
369
370 spin_unlock_irqrestore(&host_ts.lock, flags);
371
372 /* Schedule work to do do_settimeofday64() */
373 if (adj_flags & ICTIMESYNCFLAG_SYNC)
374 schedule_work(&adj_time_work);
375}
376
377/*
378 * Time Sync Channel message handler.
379 */
380static void timesync_onchannelcallback(void *context)
381{
382 struct vmbus_channel *channel = context;
383 u32 recvlen;
384 u64 requestid;
385 struct icmsg_hdr *icmsghdrp;
386 struct ictimesync_data *timedatap;
387 struct ictimesync_ref_data *refdata;
388 u8 *time_txf_buf = util_timesynch.recv_buffer;
389
390 /*
391 * Drain the ring buffer and use the last packet to update
392 * host_ts
393 */
394 while (1) {
395 int ret = vmbus_recvpacket(channel, time_txf_buf,
396 HV_HYP_PAGE_SIZE, &recvlen,
397 &requestid);
398 if (ret) {
399 pr_warn_once("TimeSync IC pkt recv failed (Err: %d)\n",
400 ret);
401 break;
402 }
403
404 if (!recvlen)
405 break;
406
407 icmsghdrp = (struct icmsg_hdr *)&time_txf_buf[
408 sizeof(struct vmbuspipe_hdr)];
409
410 if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) {
411 if (vmbus_prep_negotiate_resp(icmsghdrp, time_txf_buf,
412 fw_versions, FW_VER_COUNT,
413 ts_versions, TS_VER_COUNT,
414 NULL, &ts_srv_version)) {
415 pr_info("TimeSync IC version %d.%d\n",
416 ts_srv_version >> 16,
417 ts_srv_version & 0xFFFF);
418 }
419 } else {
420 if (ts_srv_version > TS_VERSION_3) {
421 refdata = (struct ictimesync_ref_data *)
422 &time_txf_buf[
423 sizeof(struct vmbuspipe_hdr) +
424 sizeof(struct icmsg_hdr)];
425
426 adj_guesttime(refdata->parenttime,
427 refdata->vmreferencetime,
428 refdata->flags);
429 } else {
430 timedatap = (struct ictimesync_data *)
431 &time_txf_buf[
432 sizeof(struct vmbuspipe_hdr) +
433 sizeof(struct icmsg_hdr)];
434 adj_guesttime(timedatap->parenttime,
435 hv_read_reference_counter(),
436 timedatap->flags);
437 }
438 }
439
440 icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION
441 | ICMSGHDRFLAG_RESPONSE;
442
443 vmbus_sendpacket(channel, time_txf_buf,
444 recvlen, requestid,
445 VM_PKT_DATA_INBAND, 0);
446 }
447}
448
449/*
450 * Heartbeat functionality.
451 * Every two seconds, Hyper-V send us a heartbeat request message.
452 * we respond to this message, and Hyper-V knows we are alive.
453 */
454static void heartbeat_onchannelcallback(void *context)
455{
456 struct vmbus_channel *channel = context;
457 u32 recvlen;
458 u64 requestid;
459 struct icmsg_hdr *icmsghdrp;
460 struct heartbeat_msg_data *heartbeat_msg;
461 u8 *hbeat_txf_buf = util_heartbeat.recv_buffer;
462
463 while (1) {
464
465 vmbus_recvpacket(channel, hbeat_txf_buf,
466 HV_HYP_PAGE_SIZE, &recvlen, &requestid);
467
468 if (!recvlen)
469 break;
470
471 icmsghdrp = (struct icmsg_hdr *)&hbeat_txf_buf[
472 sizeof(struct vmbuspipe_hdr)];
473
474 if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) {
475 if (vmbus_prep_negotiate_resp(icmsghdrp,
476 hbeat_txf_buf,
477 fw_versions, FW_VER_COUNT,
478 hb_versions, HB_VER_COUNT,
479 NULL, &hb_srv_version)) {
480
481 pr_info("Heartbeat IC version %d.%d\n",
482 hb_srv_version >> 16,
483 hb_srv_version & 0xFFFF);
484 }
485 } else {
486 heartbeat_msg =
487 (struct heartbeat_msg_data *)&hbeat_txf_buf[
488 sizeof(struct vmbuspipe_hdr) +
489 sizeof(struct icmsg_hdr)];
490
491 heartbeat_msg->seq_num += 1;
492 }
493
494 icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION
495 | ICMSGHDRFLAG_RESPONSE;
496
497 vmbus_sendpacket(channel, hbeat_txf_buf,
498 recvlen, requestid,
499 VM_PKT_DATA_INBAND, 0);
500 }
501}
502
503static int util_probe(struct hv_device *dev,
504 const struct hv_vmbus_device_id *dev_id)
505{
506 struct hv_util_service *srv =
507 (struct hv_util_service *)dev_id->driver_data;
508 int ret;
509
510 srv->recv_buffer = kmalloc(HV_HYP_PAGE_SIZE * 4, GFP_KERNEL);
511 if (!srv->recv_buffer)
512 return -ENOMEM;
513 srv->channel = dev->channel;
514 if (srv->util_init) {
515 ret = srv->util_init(srv);
516 if (ret) {
517 ret = -ENODEV;
518 goto error1;
519 }
520 }
521
522 /*
523 * The set of services managed by the util driver are not performance
524 * critical and do not need batched reading. Furthermore, some services
525 * such as KVP can only handle one message from the host at a time.
526 * Turn off batched reading for all util drivers before we open the
527 * channel.
528 */
529 set_channel_read_mode(dev->channel, HV_CALL_DIRECT);
530
531 hv_set_drvdata(dev, srv);
532
533 ret = vmbus_open(dev->channel, 4 * HV_HYP_PAGE_SIZE,
534 4 * HV_HYP_PAGE_SIZE, NULL, 0, srv->util_cb,
535 dev->channel);
536 if (ret)
537 goto error;
538
539 return 0;
540
541error:
542 if (srv->util_deinit)
543 srv->util_deinit();
544error1:
545 kfree(srv->recv_buffer);
546 return ret;
547}
548
549static int util_remove(struct hv_device *dev)
550{
551 struct hv_util_service *srv = hv_get_drvdata(dev);
552
553 if (srv->util_deinit)
554 srv->util_deinit();
555 vmbus_close(dev->channel);
556 kfree(srv->recv_buffer);
557
558 return 0;
559}
560
561/*
562 * When we're in util_suspend(), all the userspace processes have been frozen
563 * (refer to hibernate() -> freeze_processes()). The userspace is thawed only
564 * after the whole resume procedure, including util_resume(), finishes.
565 */
566static int util_suspend(struct hv_device *dev)
567{
568 struct hv_util_service *srv = hv_get_drvdata(dev);
569 int ret = 0;
570
571 if (srv->util_pre_suspend) {
572 ret = srv->util_pre_suspend();
573 if (ret)
574 return ret;
575 }
576
577 vmbus_close(dev->channel);
578
579 return 0;
580}
581
582static int util_resume(struct hv_device *dev)
583{
584 struct hv_util_service *srv = hv_get_drvdata(dev);
585 int ret = 0;
586
587 if (srv->util_pre_resume) {
588 ret = srv->util_pre_resume();
589 if (ret)
590 return ret;
591 }
592
593 ret = vmbus_open(dev->channel, 4 * HV_HYP_PAGE_SIZE,
594 4 * HV_HYP_PAGE_SIZE, NULL, 0, srv->util_cb,
595 dev->channel);
596 return ret;
597}
598
599static const struct hv_vmbus_device_id id_table[] = {
600 /* Shutdown guid */
601 { HV_SHUTDOWN_GUID,
602 .driver_data = (unsigned long)&util_shutdown
603 },
604 /* Time synch guid */
605 { HV_TS_GUID,
606 .driver_data = (unsigned long)&util_timesynch
607 },
608 /* Heartbeat guid */
609 { HV_HEART_BEAT_GUID,
610 .driver_data = (unsigned long)&util_heartbeat
611 },
612 /* KVP guid */
613 { HV_KVP_GUID,
614 .driver_data = (unsigned long)&util_kvp
615 },
616 /* VSS GUID */
617 { HV_VSS_GUID,
618 .driver_data = (unsigned long)&util_vss
619 },
620 /* File copy GUID */
621 { HV_FCOPY_GUID,
622 .driver_data = (unsigned long)&util_fcopy
623 },
624 { },
625};
626
627MODULE_DEVICE_TABLE(vmbus, id_table);
628
629/* The one and only one */
630static struct hv_driver util_drv = {
631 .name = "hv_utils",
632 .id_table = id_table,
633 .probe = util_probe,
634 .remove = util_remove,
635 .suspend = util_suspend,
636 .resume = util_resume,
637 .driver = {
638 .probe_type = PROBE_PREFER_ASYNCHRONOUS,
639 },
640};
641
642static int hv_ptp_enable(struct ptp_clock_info *info,
643 struct ptp_clock_request *request, int on)
644{
645 return -EOPNOTSUPP;
646}
647
648static int hv_ptp_settime(struct ptp_clock_info *p, const struct timespec64 *ts)
649{
650 return -EOPNOTSUPP;
651}
652
653static int hv_ptp_adjfreq(struct ptp_clock_info *ptp, s32 delta)
654{
655 return -EOPNOTSUPP;
656}
657static int hv_ptp_adjtime(struct ptp_clock_info *ptp, s64 delta)
658{
659 return -EOPNOTSUPP;
660}
661
662static int hv_ptp_gettime(struct ptp_clock_info *info, struct timespec64 *ts)
663{
664 return hv_get_adj_host_time(ts);
665}
666
667static struct ptp_clock_info ptp_hyperv_info = {
668 .name = "hyperv",
669 .enable = hv_ptp_enable,
670 .adjtime = hv_ptp_adjtime,
671 .adjfreq = hv_ptp_adjfreq,
672 .gettime64 = hv_ptp_gettime,
673 .settime64 = hv_ptp_settime,
674 .owner = THIS_MODULE,
675};
676
677static struct ptp_clock *hv_ptp_clock;
678
679static int hv_timesync_init(struct hv_util_service *srv)
680{
681 /* TimeSync requires Hyper-V clocksource. */
682 if (!hv_read_reference_counter)
683 return -ENODEV;
684
685 spin_lock_init(&host_ts.lock);
686
687 INIT_WORK(&adj_time_work, hv_set_host_time);
688
689 /*
690 * ptp_clock_register() returns NULL when CONFIG_PTP_1588_CLOCK is
691 * disabled but the driver is still useful without the PTP device
692 * as it still handles the ICTIMESYNCFLAG_SYNC case.
693 */
694 hv_ptp_clock = ptp_clock_register(&ptp_hyperv_info, NULL);
695 if (IS_ERR_OR_NULL(hv_ptp_clock)) {
696 pr_err("cannot register PTP clock: %ld\n",
697 PTR_ERR(hv_ptp_clock));
698 hv_ptp_clock = NULL;
699 }
700
701 return 0;
702}
703
704static void hv_timesync_cancel_work(void)
705{
706 cancel_work_sync(&adj_time_work);
707}
708
709static int hv_timesync_pre_suspend(void)
710{
711 hv_timesync_cancel_work();
712 return 0;
713}
714
715static void hv_timesync_deinit(void)
716{
717 if (hv_ptp_clock)
718 ptp_clock_unregister(hv_ptp_clock);
719
720 hv_timesync_cancel_work();
721}
722
723static int __init init_hyperv_utils(void)
724{
725 pr_info("Registering HyperV Utility Driver\n");
726
727 return vmbus_driver_register(&util_drv);
728}
729
730static void exit_hyperv_utils(void)
731{
732 pr_info("De-Registered HyperV Utility Driver\n");
733
734 vmbus_driver_unregister(&util_drv);
735}
736
737module_init(init_hyperv_utils);
738module_exit(exit_hyperv_utils);
739
740MODULE_DESCRIPTION("Hyper-V Utilities");
741MODULE_LICENSE("GPL");
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
31#include "hyperv_vmbus.h"
32
33#define SD_MAJOR 3
34#define SD_MINOR 0
35#define SD_VERSION (SD_MAJOR << 16 | SD_MINOR)
36
37#define SD_MAJOR_1 1
38#define SD_VERSION_1 (SD_MAJOR_1 << 16 | SD_MINOR)
39
40#define TS_MAJOR 4
41#define TS_MINOR 0
42#define TS_VERSION (TS_MAJOR << 16 | TS_MINOR)
43
44#define TS_MAJOR_1 1
45#define TS_VERSION_1 (TS_MAJOR_1 << 16 | TS_MINOR)
46
47#define TS_MAJOR_3 3
48#define TS_VERSION_3 (TS_MAJOR_3 << 16 | TS_MINOR)
49
50#define HB_MAJOR 3
51#define HB_MINOR 0
52#define HB_VERSION (HB_MAJOR << 16 | HB_MINOR)
53
54#define HB_MAJOR_1 1
55#define HB_VERSION_1 (HB_MAJOR_1 << 16 | HB_MINOR)
56
57static int sd_srv_version;
58static int ts_srv_version;
59static int hb_srv_version;
60static int util_fw_version;
61
62static void shutdown_onchannelcallback(void *context);
63static struct hv_util_service util_shutdown = {
64 .util_cb = shutdown_onchannelcallback,
65};
66
67static int hv_timesync_init(struct hv_util_service *srv);
68static void hv_timesync_deinit(void);
69
70static void timesync_onchannelcallback(void *context);
71static struct hv_util_service util_timesynch = {
72 .util_cb = timesync_onchannelcallback,
73 .util_init = hv_timesync_init,
74 .util_deinit = hv_timesync_deinit,
75};
76
77static void heartbeat_onchannelcallback(void *context);
78static struct hv_util_service util_heartbeat = {
79 .util_cb = heartbeat_onchannelcallback,
80};
81
82static struct hv_util_service util_kvp = {
83 .util_cb = hv_kvp_onchannelcallback,
84 .util_init = hv_kvp_init,
85 .util_deinit = hv_kvp_deinit,
86};
87
88static struct hv_util_service util_vss = {
89 .util_cb = hv_vss_onchannelcallback,
90 .util_init = hv_vss_init,
91 .util_deinit = hv_vss_deinit,
92};
93
94static struct hv_util_service util_fcopy = {
95 .util_cb = hv_fcopy_onchannelcallback,
96 .util_init = hv_fcopy_init,
97 .util_deinit = hv_fcopy_deinit,
98};
99
100static void perform_shutdown(struct work_struct *dummy)
101{
102 orderly_poweroff(true);
103}
104
105/*
106 * Perform the shutdown operation in a thread context.
107 */
108static DECLARE_WORK(shutdown_work, perform_shutdown);
109
110static void shutdown_onchannelcallback(void *context)
111{
112 struct vmbus_channel *channel = context;
113 u32 recvlen;
114 u64 requestid;
115 bool execute_shutdown = false;
116 u8 *shut_txf_buf = util_shutdown.recv_buffer;
117
118 struct shutdown_msg_data *shutdown_msg;
119
120 struct icmsg_hdr *icmsghdrp;
121 struct icmsg_negotiate *negop = NULL;
122
123 vmbus_recvpacket(channel, shut_txf_buf,
124 PAGE_SIZE, &recvlen, &requestid);
125
126 if (recvlen > 0) {
127 icmsghdrp = (struct icmsg_hdr *)&shut_txf_buf[
128 sizeof(struct vmbuspipe_hdr)];
129
130 if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) {
131 vmbus_prep_negotiate_resp(icmsghdrp, negop,
132 shut_txf_buf, util_fw_version,
133 sd_srv_version);
134 } else {
135 shutdown_msg =
136 (struct shutdown_msg_data *)&shut_txf_buf[
137 sizeof(struct vmbuspipe_hdr) +
138 sizeof(struct icmsg_hdr)];
139
140 switch (shutdown_msg->flags) {
141 case 0:
142 case 1:
143 icmsghdrp->status = HV_S_OK;
144 execute_shutdown = true;
145
146 pr_info("Shutdown request received -"
147 " graceful shutdown initiated\n");
148 break;
149 default:
150 icmsghdrp->status = HV_E_FAIL;
151 execute_shutdown = false;
152
153 pr_info("Shutdown request received -"
154 " Invalid request\n");
155 break;
156 }
157 }
158
159 icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION
160 | ICMSGHDRFLAG_RESPONSE;
161
162 vmbus_sendpacket(channel, shut_txf_buf,
163 recvlen, requestid,
164 VM_PKT_DATA_INBAND, 0);
165 }
166
167 if (execute_shutdown == true)
168 schedule_work(&shutdown_work);
169}
170
171/*
172 * Set the host time in a process context.
173 */
174
175struct adj_time_work {
176 struct work_struct work;
177 u64 host_time;
178 u64 ref_time;
179 u8 flags;
180};
181
182static void hv_set_host_time(struct work_struct *work)
183{
184 struct adj_time_work *wrk;
185 s64 host_tns;
186 u64 newtime;
187 struct timespec host_ts;
188
189 wrk = container_of(work, struct adj_time_work, work);
190
191 newtime = wrk->host_time;
192 if (ts_srv_version > TS_VERSION_3) {
193 /*
194 * Some latency has been introduced since Hyper-V generated
195 * its time sample. Take that latency into account before
196 * using TSC reference time sample from Hyper-V.
197 *
198 * This sample is given by TimeSync v4 and above hosts.
199 */
200 u64 current_tick;
201
202 rdmsrl(HV_X64_MSR_TIME_REF_COUNT, current_tick);
203 newtime += (current_tick - wrk->ref_time);
204 }
205 host_tns = (newtime - WLTIMEDELTA) * 100;
206 host_ts = ns_to_timespec(host_tns);
207
208 do_settimeofday(&host_ts);
209}
210
211/*
212 * Synchronize time with host after reboot, restore, etc.
213 *
214 * ICTIMESYNCFLAG_SYNC flag bit indicates reboot, restore events of the VM.
215 * After reboot the flag ICTIMESYNCFLAG_SYNC is included in the first time
216 * message after the timesync channel is opened. Since the hv_utils module is
217 * loaded after hv_vmbus, the first message is usually missed. This bit is
218 * considered a hard request to discipline the clock.
219 *
220 * ICTIMESYNCFLAG_SAMPLE bit indicates a time sample from host. This is
221 * typically used as a hint to the guest. The guest is under no obligation
222 * to discipline the clock.
223 */
224static struct adj_time_work wrk;
225static inline void adj_guesttime(u64 hosttime, u64 reftime, u8 flags)
226{
227
228 /*
229 * This check is safe since we are executing in the
230 * interrupt context and time synch messages arre always
231 * delivered on the same CPU.
232 */
233 if (work_pending(&wrk.work))
234 return;
235
236 wrk.host_time = hosttime;
237 wrk.ref_time = reftime;
238 wrk.flags = flags;
239 if ((flags & (ICTIMESYNCFLAG_SYNC | ICTIMESYNCFLAG_SAMPLE)) != 0) {
240 schedule_work(&wrk.work);
241 }
242}
243
244/*
245 * Time Sync Channel message handler.
246 */
247static void timesync_onchannelcallback(void *context)
248{
249 struct vmbus_channel *channel = context;
250 u32 recvlen;
251 u64 requestid;
252 struct icmsg_hdr *icmsghdrp;
253 struct ictimesync_data *timedatap;
254 struct ictimesync_ref_data *refdata;
255 u8 *time_txf_buf = util_timesynch.recv_buffer;
256 struct icmsg_negotiate *negop = NULL;
257
258 vmbus_recvpacket(channel, time_txf_buf,
259 PAGE_SIZE, &recvlen, &requestid);
260
261 if (recvlen > 0) {
262 icmsghdrp = (struct icmsg_hdr *)&time_txf_buf[
263 sizeof(struct vmbuspipe_hdr)];
264
265 if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) {
266 vmbus_prep_negotiate_resp(icmsghdrp, negop,
267 time_txf_buf,
268 util_fw_version,
269 ts_srv_version);
270 pr_info("Using TimeSync version %d.%d\n",
271 ts_srv_version >> 16, ts_srv_version & 0xFFFF);
272 } else {
273 if (ts_srv_version > TS_VERSION_3) {
274 refdata = (struct ictimesync_ref_data *)
275 &time_txf_buf[
276 sizeof(struct vmbuspipe_hdr) +
277 sizeof(struct icmsg_hdr)];
278
279 adj_guesttime(refdata->parenttime,
280 refdata->vmreferencetime,
281 refdata->flags);
282 } else {
283 timedatap = (struct ictimesync_data *)
284 &time_txf_buf[
285 sizeof(struct vmbuspipe_hdr) +
286 sizeof(struct icmsg_hdr)];
287 adj_guesttime(timedatap->parenttime,
288 0,
289 timedatap->flags);
290 }
291 }
292
293 icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION
294 | ICMSGHDRFLAG_RESPONSE;
295
296 vmbus_sendpacket(channel, time_txf_buf,
297 recvlen, requestid,
298 VM_PKT_DATA_INBAND, 0);
299 }
300}
301
302/*
303 * Heartbeat functionality.
304 * Every two seconds, Hyper-V send us a heartbeat request message.
305 * we respond to this message, and Hyper-V knows we are alive.
306 */
307static void heartbeat_onchannelcallback(void *context)
308{
309 struct vmbus_channel *channel = context;
310 u32 recvlen;
311 u64 requestid;
312 struct icmsg_hdr *icmsghdrp;
313 struct heartbeat_msg_data *heartbeat_msg;
314 u8 *hbeat_txf_buf = util_heartbeat.recv_buffer;
315 struct icmsg_negotiate *negop = NULL;
316
317 while (1) {
318
319 vmbus_recvpacket(channel, hbeat_txf_buf,
320 PAGE_SIZE, &recvlen, &requestid);
321
322 if (!recvlen)
323 break;
324
325 icmsghdrp = (struct icmsg_hdr *)&hbeat_txf_buf[
326 sizeof(struct vmbuspipe_hdr)];
327
328 if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) {
329 vmbus_prep_negotiate_resp(icmsghdrp, negop,
330 hbeat_txf_buf, util_fw_version,
331 hb_srv_version);
332 } else {
333 heartbeat_msg =
334 (struct heartbeat_msg_data *)&hbeat_txf_buf[
335 sizeof(struct vmbuspipe_hdr) +
336 sizeof(struct icmsg_hdr)];
337
338 heartbeat_msg->seq_num += 1;
339 }
340
341 icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION
342 | ICMSGHDRFLAG_RESPONSE;
343
344 vmbus_sendpacket(channel, hbeat_txf_buf,
345 recvlen, requestid,
346 VM_PKT_DATA_INBAND, 0);
347 }
348}
349
350static int util_probe(struct hv_device *dev,
351 const struct hv_vmbus_device_id *dev_id)
352{
353 struct hv_util_service *srv =
354 (struct hv_util_service *)dev_id->driver_data;
355 int ret;
356
357 srv->recv_buffer = kmalloc(PAGE_SIZE * 4, GFP_KERNEL);
358 if (!srv->recv_buffer)
359 return -ENOMEM;
360 srv->channel = dev->channel;
361 if (srv->util_init) {
362 ret = srv->util_init(srv);
363 if (ret) {
364 ret = -ENODEV;
365 goto error1;
366 }
367 }
368
369 /*
370 * The set of services managed by the util driver are not performance
371 * critical and do not need batched reading. Furthermore, some services
372 * such as KVP can only handle one message from the host at a time.
373 * Turn off batched reading for all util drivers before we open the
374 * channel.
375 */
376
377 set_channel_read_state(dev->channel, false);
378
379 hv_set_drvdata(dev, srv);
380
381 /*
382 * Based on the host; initialize the framework and
383 * service version numbers we will negotiate.
384 */
385 switch (vmbus_proto_version) {
386 case (VERSION_WS2008):
387 util_fw_version = UTIL_WS2K8_FW_VERSION;
388 sd_srv_version = SD_VERSION_1;
389 ts_srv_version = TS_VERSION_1;
390 hb_srv_version = HB_VERSION_1;
391 break;
392 case VERSION_WIN7:
393 case VERSION_WIN8:
394 case VERSION_WIN8_1:
395 util_fw_version = UTIL_FW_VERSION;
396 sd_srv_version = SD_VERSION;
397 ts_srv_version = TS_VERSION_3;
398 hb_srv_version = HB_VERSION;
399 break;
400 case VERSION_WIN10:
401 default:
402 util_fw_version = UTIL_FW_VERSION;
403 sd_srv_version = SD_VERSION;
404 ts_srv_version = TS_VERSION;
405 hb_srv_version = HB_VERSION;
406 }
407
408 ret = vmbus_open(dev->channel, 4 * PAGE_SIZE, 4 * PAGE_SIZE, NULL, 0,
409 srv->util_cb, dev->channel);
410 if (ret)
411 goto error;
412
413 return 0;
414
415error:
416 if (srv->util_deinit)
417 srv->util_deinit();
418error1:
419 kfree(srv->recv_buffer);
420 return ret;
421}
422
423static int util_remove(struct hv_device *dev)
424{
425 struct hv_util_service *srv = hv_get_drvdata(dev);
426
427 if (srv->util_deinit)
428 srv->util_deinit();
429 vmbus_close(dev->channel);
430 kfree(srv->recv_buffer);
431
432 return 0;
433}
434
435static const struct hv_vmbus_device_id id_table[] = {
436 /* Shutdown guid */
437 { HV_SHUTDOWN_GUID,
438 .driver_data = (unsigned long)&util_shutdown
439 },
440 /* Time synch guid */
441 { HV_TS_GUID,
442 .driver_data = (unsigned long)&util_timesynch
443 },
444 /* Heartbeat guid */
445 { HV_HEART_BEAT_GUID,
446 .driver_data = (unsigned long)&util_heartbeat
447 },
448 /* KVP guid */
449 { HV_KVP_GUID,
450 .driver_data = (unsigned long)&util_kvp
451 },
452 /* VSS GUID */
453 { HV_VSS_GUID,
454 .driver_data = (unsigned long)&util_vss
455 },
456 /* File copy GUID */
457 { HV_FCOPY_GUID,
458 .driver_data = (unsigned long)&util_fcopy
459 },
460 { },
461};
462
463MODULE_DEVICE_TABLE(vmbus, id_table);
464
465/* The one and only one */
466static struct hv_driver util_drv = {
467 .name = "hv_util",
468 .id_table = id_table,
469 .probe = util_probe,
470 .remove = util_remove,
471};
472
473static int hv_timesync_init(struct hv_util_service *srv)
474{
475 INIT_WORK(&wrk.work, hv_set_host_time);
476 return 0;
477}
478
479static void hv_timesync_deinit(void)
480{
481 cancel_work_sync(&wrk.work);
482}
483
484static int __init init_hyperv_utils(void)
485{
486 pr_info("Registering HyperV Utility Driver\n");
487
488 return vmbus_driver_register(&util_drv);
489}
490
491static void exit_hyperv_utils(void)
492{
493 pr_info("De-Registered HyperV Utility Driver\n");
494
495 vmbus_driver_unregister(&util_drv);
496}
497
498module_init(init_hyperv_utils);
499module_exit(exit_hyperv_utils);
500
501MODULE_DESCRIPTION("Hyper-V Utilities");
502MODULE_LICENSE("GPL");