xref: /linux/drivers/hv/hv_util.c (revision bb5b94f5bbe75470912b70fb08880fc5273aa62d)
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 
53 static int sd_srv_version;
54 static int ts_srv_version;
55 static int hb_srv_version;
56 
57 #define SD_VER_COUNT 4
58 static 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
66 static const int ts_versions[] = {
67 	TS_VERSION,
68 	TS_VERSION_3,
69 	TS_VERSION_1
70 };
71 
72 #define HB_VER_COUNT 2
73 static const int hb_versions[] = {
74 	HB_VERSION,
75 	HB_VERSION_1
76 };
77 
78 #define FW_VER_COUNT 2
79 static 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  */
87 struct hibernate_work_context {
88 	struct work_struct work;
89 	struct hv_device *dev;
90 };
91 
92 static struct hibernate_work_context hibernate_context;
93 static bool hibernation_supported;
94 
95 static 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 
107 static 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 
119 static void shutdown_onchannelcallback(void *context);
120 static struct hv_util_service util_shutdown = {
121 	.util_cb = shutdown_onchannelcallback,
122 	.util_init = hv_shutdown_init,
123 };
124 
125 static int hv_timesync_init(struct hv_util_service *srv);
126 static int hv_timesync_pre_suspend(void);
127 static void hv_timesync_deinit(void);
128 
129 static void timesync_onchannelcallback(void *context);
130 static 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 
137 static void heartbeat_onchannelcallback(void *context);
138 static struct hv_util_service util_heartbeat = {
139 	.util_cb = heartbeat_onchannelcallback,
140 };
141 
142 static 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 
150 static 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 
158 static 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 
166 static void perform_shutdown(struct work_struct *dummy)
167 {
168 	orderly_poweroff(true);
169 }
170 
171 static void perform_restart(struct work_struct *dummy)
172 {
173 	orderly_reboot();
174 }
175 
176 /*
177  * Perform the shutdown operation in a thread context.
178  */
179 static DECLARE_WORK(shutdown_work, perform_shutdown);
180 
181 /*
182  * Perform the restart operation in a thread context.
183  */
184 static DECLARE_WORK(restart_work, perform_restart);
185 
186 static 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 	if (vmbus_recvpacket(channel, shut_txf_buf, HV_HYP_PAGE_SIZE, &recvlen, &requestid)) {
199 		pr_err_ratelimited("Shutdown request received. Could not read into shut txf buf\n");
200 		return;
201 	}
202 
203 	if (!recvlen)
204 		return;
205 
206 	/* Ensure recvlen is big enough to read header data */
207 	if (recvlen < ICMSG_HDR) {
208 		pr_err_ratelimited("Shutdown request received. Packet length too small: %d\n",
209 				   recvlen);
210 		return;
211 	}
212 
213 	icmsghdrp = (struct icmsg_hdr *)&shut_txf_buf[sizeof(struct vmbuspipe_hdr)];
214 
215 	if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) {
216 		if (vmbus_prep_negotiate_resp(icmsghdrp,
217 				shut_txf_buf, recvlen,
218 				fw_versions, FW_VER_COUNT,
219 				sd_versions, SD_VER_COUNT,
220 				NULL, &sd_srv_version)) {
221 			pr_info("Shutdown IC version %d.%d\n",
222 				sd_srv_version >> 16,
223 				sd_srv_version & 0xFFFF);
224 		}
225 	} else if (icmsghdrp->icmsgtype == ICMSGTYPE_SHUTDOWN) {
226 		/* Ensure recvlen is big enough to contain shutdown_msg_data struct */
227 		if (recvlen < ICMSG_HDR + sizeof(struct shutdown_msg_data)) {
228 			pr_err_ratelimited("Invalid shutdown msg data. Packet length too small: %u\n",
229 					   recvlen);
230 			return;
231 		}
232 
233 		shutdown_msg = (struct shutdown_msg_data *)&shut_txf_buf[ICMSG_HDR];
234 
235 		/*
236 		 * shutdown_msg->flags can be 0(shut down), 2(reboot),
237 		 * or 4(hibernate). It may bitwise-OR 1, which means
238 		 * performing the request by force. Linux always tries
239 		 * to perform the request by force.
240 		 */
241 		switch (shutdown_msg->flags) {
242 		case 0:
243 		case 1:
244 			icmsghdrp->status = HV_S_OK;
245 			work = &shutdown_work;
246 			pr_info("Shutdown request received - graceful shutdown initiated\n");
247 			break;
248 		case 2:
249 		case 3:
250 			icmsghdrp->status = HV_S_OK;
251 			work = &restart_work;
252 			pr_info("Restart request received - graceful restart initiated\n");
253 			break;
254 		case 4:
255 		case 5:
256 			pr_info("Hibernation request received\n");
257 			icmsghdrp->status = hibernation_supported ?
258 				HV_S_OK : HV_E_FAIL;
259 			if (hibernation_supported)
260 				work = &hibernate_context.work;
261 			break;
262 		default:
263 			icmsghdrp->status = HV_E_FAIL;
264 			pr_info("Shutdown request received - Invalid request\n");
265 			break;
266 		}
267 	} else {
268 		icmsghdrp->status = HV_E_FAIL;
269 		pr_err_ratelimited("Shutdown request received. Invalid msg type: %d\n",
270 				   icmsghdrp->icmsgtype);
271 	}
272 
273 	icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION
274 		| ICMSGHDRFLAG_RESPONSE;
275 
276 	vmbus_sendpacket(channel, shut_txf_buf,
277 			 recvlen, requestid,
278 			 VM_PKT_DATA_INBAND, 0);
279 
280 	if (work)
281 		schedule_work(work);
282 }
283 
284 /*
285  * Set the host time in a process context.
286  */
287 static struct work_struct adj_time_work;
288 
289 /*
290  * The last time sample, received from the host. PTP device responds to
291  * requests by using this data and the current partition-wide time reference
292  * count.
293  */
294 static struct {
295 	u64				host_time;
296 	u64				ref_time;
297 	spinlock_t			lock;
298 } host_ts;
299 
300 static inline u64 reftime_to_ns(u64 reftime)
301 {
302 	return (reftime - WLTIMEDELTA) * 100;
303 }
304 
305 /*
306  * Hard coded threshold for host timesync delay: 600 seconds
307  */
308 static const u64 HOST_TIMESYNC_DELAY_THRESH = 600 * (u64)NSEC_PER_SEC;
309 
310 static int hv_get_adj_host_time(struct timespec64 *ts)
311 {
312 	u64 newtime, reftime, timediff_adj;
313 	unsigned long flags;
314 	int ret = 0;
315 
316 	spin_lock_irqsave(&host_ts.lock, flags);
317 	reftime = hv_read_reference_counter();
318 
319 	/*
320 	 * We need to let the caller know that last update from host
321 	 * is older than the max allowable threshold. clock_gettime()
322 	 * and PTP ioctl do not have a documented error that we could
323 	 * return for this specific case. Use ESTALE to report this.
324 	 */
325 	timediff_adj = reftime - host_ts.ref_time;
326 	if (timediff_adj * 100 > HOST_TIMESYNC_DELAY_THRESH) {
327 		pr_warn_once("TIMESYNC IC: Stale time stamp, %llu nsecs old\n",
328 			     (timediff_adj * 100));
329 		ret = -ESTALE;
330 	}
331 
332 	newtime = host_ts.host_time + timediff_adj;
333 	*ts = ns_to_timespec64(reftime_to_ns(newtime));
334 	spin_unlock_irqrestore(&host_ts.lock, flags);
335 
336 	return ret;
337 }
338 
339 static void hv_set_host_time(struct work_struct *work)
340 {
341 
342 	struct timespec64 ts;
343 
344 	if (!hv_get_adj_host_time(&ts))
345 		do_settimeofday64(&ts);
346 }
347 
348 /*
349  * Synchronize time with host after reboot, restore, etc.
350  *
351  * ICTIMESYNCFLAG_SYNC flag bit indicates reboot, restore events of the VM.
352  * After reboot the flag ICTIMESYNCFLAG_SYNC is included in the first time
353  * message after the timesync channel is opened. Since the hv_utils module is
354  * loaded after hv_vmbus, the first message is usually missed. This bit is
355  * considered a hard request to discipline the clock.
356  *
357  * ICTIMESYNCFLAG_SAMPLE bit indicates a time sample from host. This is
358  * typically used as a hint to the guest. The guest is under no obligation
359  * to discipline the clock.
360  */
361 static inline void adj_guesttime(u64 hosttime, u64 reftime, u8 adj_flags)
362 {
363 	unsigned long flags;
364 	u64 cur_reftime;
365 
366 	/*
367 	 * Save the adjusted time sample from the host and the snapshot
368 	 * of the current system time.
369 	 */
370 	spin_lock_irqsave(&host_ts.lock, flags);
371 
372 	cur_reftime = hv_read_reference_counter();
373 	host_ts.host_time = hosttime;
374 	host_ts.ref_time = cur_reftime;
375 
376 	/*
377 	 * TimeSync v4 messages contain reference time (guest's Hyper-V
378 	 * clocksource read when the time sample was generated), we can
379 	 * improve the precision by adding the delta between now and the
380 	 * time of generation. For older protocols we set
381 	 * reftime == cur_reftime on call.
382 	 */
383 	host_ts.host_time += (cur_reftime - reftime);
384 
385 	spin_unlock_irqrestore(&host_ts.lock, flags);
386 
387 	/* Schedule work to do do_settimeofday64() */
388 	if (adj_flags & ICTIMESYNCFLAG_SYNC)
389 		schedule_work(&adj_time_work);
390 }
391 
392 /*
393  * Time Sync Channel message handler.
394  */
395 static void timesync_onchannelcallback(void *context)
396 {
397 	struct vmbus_channel *channel = context;
398 	u32 recvlen;
399 	u64 requestid;
400 	struct icmsg_hdr *icmsghdrp;
401 	struct ictimesync_data *timedatap;
402 	struct ictimesync_ref_data *refdata;
403 	u8 *time_txf_buf = util_timesynch.recv_buffer;
404 
405 	/*
406 	 * Drain the ring buffer and use the last packet to update
407 	 * host_ts
408 	 */
409 	while (1) {
410 		int ret = vmbus_recvpacket(channel, time_txf_buf,
411 					   HV_HYP_PAGE_SIZE, &recvlen,
412 					   &requestid);
413 		if (ret) {
414 			pr_err_ratelimited("TimeSync IC pkt recv failed (Err: %d)\n",
415 					   ret);
416 			break;
417 		}
418 
419 		if (!recvlen)
420 			break;
421 
422 		/* Ensure recvlen is big enough to read header data */
423 		if (recvlen < ICMSG_HDR) {
424 			pr_err_ratelimited("Timesync request received. Packet length too small: %d\n",
425 					   recvlen);
426 			break;
427 		}
428 
429 		icmsghdrp = (struct icmsg_hdr *)&time_txf_buf[
430 				sizeof(struct vmbuspipe_hdr)];
431 
432 		if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) {
433 			if (vmbus_prep_negotiate_resp(icmsghdrp,
434 						time_txf_buf, recvlen,
435 						fw_versions, FW_VER_COUNT,
436 						ts_versions, TS_VER_COUNT,
437 						NULL, &ts_srv_version)) {
438 				pr_info("TimeSync IC version %d.%d\n",
439 					ts_srv_version >> 16,
440 					ts_srv_version & 0xFFFF);
441 			}
442 		} else if (icmsghdrp->icmsgtype == ICMSGTYPE_TIMESYNC) {
443 			if (ts_srv_version > TS_VERSION_3) {
444 				/* Ensure recvlen is big enough to read ictimesync_ref_data */
445 				if (recvlen < ICMSG_HDR + sizeof(struct ictimesync_ref_data)) {
446 					pr_err_ratelimited("Invalid ictimesync ref data. Length too small: %u\n",
447 							   recvlen);
448 					break;
449 				}
450 				refdata = (struct ictimesync_ref_data *)&time_txf_buf[ICMSG_HDR];
451 
452 				adj_guesttime(refdata->parenttime,
453 						refdata->vmreferencetime,
454 						refdata->flags);
455 			} else {
456 				/* Ensure recvlen is big enough to read ictimesync_data */
457 				if (recvlen < ICMSG_HDR + sizeof(struct ictimesync_data)) {
458 					pr_err_ratelimited("Invalid ictimesync data. Length too small: %u\n",
459 							   recvlen);
460 					break;
461 				}
462 				timedatap = (struct ictimesync_data *)&time_txf_buf[ICMSG_HDR];
463 
464 				adj_guesttime(timedatap->parenttime,
465 					      hv_read_reference_counter(),
466 					      timedatap->flags);
467 			}
468 		} else {
469 			icmsghdrp->status = HV_E_FAIL;
470 			pr_err_ratelimited("Timesync request received. Invalid msg type: %d\n",
471 					   icmsghdrp->icmsgtype);
472 		}
473 
474 		icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION
475 			| ICMSGHDRFLAG_RESPONSE;
476 
477 		vmbus_sendpacket(channel, time_txf_buf,
478 				 recvlen, requestid,
479 				 VM_PKT_DATA_INBAND, 0);
480 	}
481 }
482 
483 /*
484  * Heartbeat functionality.
485  * Every two seconds, Hyper-V send us a heartbeat request message.
486  * we respond to this message, and Hyper-V knows we are alive.
487  */
488 static void heartbeat_onchannelcallback(void *context)
489 {
490 	struct vmbus_channel *channel = context;
491 	u32 recvlen;
492 	u64 requestid;
493 	struct icmsg_hdr *icmsghdrp;
494 	struct heartbeat_msg_data *heartbeat_msg;
495 	u8 *hbeat_txf_buf = util_heartbeat.recv_buffer;
496 
497 	while (1) {
498 
499 		if (vmbus_recvpacket(channel, hbeat_txf_buf, HV_HYP_PAGE_SIZE,
500 				     &recvlen, &requestid)) {
501 			pr_err_ratelimited("Heartbeat request received. Could not read into hbeat txf buf\n");
502 			return;
503 		}
504 
505 		if (!recvlen)
506 			break;
507 
508 		/* Ensure recvlen is big enough to read header data */
509 		if (recvlen < ICMSG_HDR) {
510 			pr_err_ratelimited("Heartbeat request received. Packet length too small: %d\n",
511 					   recvlen);
512 			break;
513 		}
514 
515 		icmsghdrp = (struct icmsg_hdr *)&hbeat_txf_buf[
516 				sizeof(struct vmbuspipe_hdr)];
517 
518 		if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) {
519 			if (vmbus_prep_negotiate_resp(icmsghdrp,
520 					hbeat_txf_buf, recvlen,
521 					fw_versions, FW_VER_COUNT,
522 					hb_versions, HB_VER_COUNT,
523 					NULL, &hb_srv_version)) {
524 
525 				pr_info("Heartbeat IC version %d.%d\n",
526 					hb_srv_version >> 16,
527 					hb_srv_version & 0xFFFF);
528 			}
529 		} else if (icmsghdrp->icmsgtype == ICMSGTYPE_HEARTBEAT) {
530 			/*
531 			 * Ensure recvlen is big enough to read seq_num. Reserved area is not
532 			 * included in the check as the host may not fill it up entirely
533 			 */
534 			if (recvlen < ICMSG_HDR + sizeof(u64)) {
535 				pr_err_ratelimited("Invalid heartbeat msg data. Length too small: %u\n",
536 						   recvlen);
537 				break;
538 			}
539 			heartbeat_msg = (struct heartbeat_msg_data *)&hbeat_txf_buf[ICMSG_HDR];
540 
541 			heartbeat_msg->seq_num += 1;
542 		} else {
543 			icmsghdrp->status = HV_E_FAIL;
544 			pr_err_ratelimited("Heartbeat request received. Invalid msg type: %d\n",
545 					   icmsghdrp->icmsgtype);
546 		}
547 
548 		icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION
549 			| ICMSGHDRFLAG_RESPONSE;
550 
551 		vmbus_sendpacket(channel, hbeat_txf_buf,
552 				 recvlen, requestid,
553 				 VM_PKT_DATA_INBAND, 0);
554 	}
555 }
556 
557 #define HV_UTIL_RING_SEND_SIZE VMBUS_RING_SIZE(3 * HV_HYP_PAGE_SIZE)
558 #define HV_UTIL_RING_RECV_SIZE VMBUS_RING_SIZE(3 * HV_HYP_PAGE_SIZE)
559 
560 static int util_probe(struct hv_device *dev,
561 			const struct hv_vmbus_device_id *dev_id)
562 {
563 	struct hv_util_service *srv =
564 		(struct hv_util_service *)dev_id->driver_data;
565 	int ret;
566 
567 	srv->recv_buffer = kmalloc(HV_HYP_PAGE_SIZE * 4, GFP_KERNEL);
568 	if (!srv->recv_buffer)
569 		return -ENOMEM;
570 	srv->channel = dev->channel;
571 	if (srv->util_init) {
572 		ret = srv->util_init(srv);
573 		if (ret) {
574 			ret = -ENODEV;
575 			goto error1;
576 		}
577 	}
578 
579 	/*
580 	 * The set of services managed by the util driver are not performance
581 	 * critical and do not need batched reading. Furthermore, some services
582 	 * such as KVP can only handle one message from the host at a time.
583 	 * Turn off batched reading for all util drivers before we open the
584 	 * channel.
585 	 */
586 	set_channel_read_mode(dev->channel, HV_CALL_DIRECT);
587 
588 	hv_set_drvdata(dev, srv);
589 
590 	ret = vmbus_open(dev->channel, HV_UTIL_RING_SEND_SIZE,
591 			 HV_UTIL_RING_RECV_SIZE, NULL, 0, srv->util_cb,
592 			 dev->channel);
593 	if (ret)
594 		goto error;
595 
596 	return 0;
597 
598 error:
599 	if (srv->util_deinit)
600 		srv->util_deinit();
601 error1:
602 	kfree(srv->recv_buffer);
603 	return ret;
604 }
605 
606 static int util_remove(struct hv_device *dev)
607 {
608 	struct hv_util_service *srv = hv_get_drvdata(dev);
609 
610 	if (srv->util_deinit)
611 		srv->util_deinit();
612 	vmbus_close(dev->channel);
613 	kfree(srv->recv_buffer);
614 
615 	return 0;
616 }
617 
618 /*
619  * When we're in util_suspend(), all the userspace processes have been frozen
620  * (refer to hibernate() -> freeze_processes()). The userspace is thawed only
621  * after the whole resume procedure, including util_resume(), finishes.
622  */
623 static int util_suspend(struct hv_device *dev)
624 {
625 	struct hv_util_service *srv = hv_get_drvdata(dev);
626 	int ret = 0;
627 
628 	if (srv->util_pre_suspend) {
629 		ret = srv->util_pre_suspend();
630 		if (ret)
631 			return ret;
632 	}
633 
634 	vmbus_close(dev->channel);
635 
636 	return 0;
637 }
638 
639 static int util_resume(struct hv_device *dev)
640 {
641 	struct hv_util_service *srv = hv_get_drvdata(dev);
642 	int ret = 0;
643 
644 	if (srv->util_pre_resume) {
645 		ret = srv->util_pre_resume();
646 		if (ret)
647 			return ret;
648 	}
649 
650 	ret = vmbus_open(dev->channel, HV_UTIL_RING_SEND_SIZE,
651 			 HV_UTIL_RING_RECV_SIZE, NULL, 0, srv->util_cb,
652 			 dev->channel);
653 	return ret;
654 }
655 
656 static const struct hv_vmbus_device_id id_table[] = {
657 	/* Shutdown guid */
658 	{ HV_SHUTDOWN_GUID,
659 	  .driver_data = (unsigned long)&util_shutdown
660 	},
661 	/* Time synch guid */
662 	{ HV_TS_GUID,
663 	  .driver_data = (unsigned long)&util_timesynch
664 	},
665 	/* Heartbeat guid */
666 	{ HV_HEART_BEAT_GUID,
667 	  .driver_data = (unsigned long)&util_heartbeat
668 	},
669 	/* KVP guid */
670 	{ HV_KVP_GUID,
671 	  .driver_data = (unsigned long)&util_kvp
672 	},
673 	/* VSS GUID */
674 	{ HV_VSS_GUID,
675 	  .driver_data = (unsigned long)&util_vss
676 	},
677 	/* File copy GUID */
678 	{ HV_FCOPY_GUID,
679 	  .driver_data = (unsigned long)&util_fcopy
680 	},
681 	{ },
682 };
683 
684 MODULE_DEVICE_TABLE(vmbus, id_table);
685 
686 /* The one and only one */
687 static  struct hv_driver util_drv = {
688 	.name = "hv_utils",
689 	.id_table = id_table,
690 	.probe =  util_probe,
691 	.remove =  util_remove,
692 	.suspend = util_suspend,
693 	.resume =  util_resume,
694 	.driver = {
695 		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
696 	},
697 };
698 
699 static int hv_ptp_enable(struct ptp_clock_info *info,
700 			 struct ptp_clock_request *request, int on)
701 {
702 	return -EOPNOTSUPP;
703 }
704 
705 static int hv_ptp_settime(struct ptp_clock_info *p, const struct timespec64 *ts)
706 {
707 	return -EOPNOTSUPP;
708 }
709 
710 static int hv_ptp_adjfreq(struct ptp_clock_info *ptp, s32 delta)
711 {
712 	return -EOPNOTSUPP;
713 }
714 static int hv_ptp_adjtime(struct ptp_clock_info *ptp, s64 delta)
715 {
716 	return -EOPNOTSUPP;
717 }
718 
719 static int hv_ptp_gettime(struct ptp_clock_info *info, struct timespec64 *ts)
720 {
721 	return hv_get_adj_host_time(ts);
722 }
723 
724 static struct ptp_clock_info ptp_hyperv_info = {
725 	.name		= "hyperv",
726 	.enable         = hv_ptp_enable,
727 	.adjtime        = hv_ptp_adjtime,
728 	.adjfreq        = hv_ptp_adjfreq,
729 	.gettime64      = hv_ptp_gettime,
730 	.settime64      = hv_ptp_settime,
731 	.owner		= THIS_MODULE,
732 };
733 
734 static struct ptp_clock *hv_ptp_clock;
735 
736 static int hv_timesync_init(struct hv_util_service *srv)
737 {
738 	/* TimeSync requires Hyper-V clocksource. */
739 	if (!hv_read_reference_counter)
740 		return -ENODEV;
741 
742 	spin_lock_init(&host_ts.lock);
743 
744 	INIT_WORK(&adj_time_work, hv_set_host_time);
745 
746 	/*
747 	 * ptp_clock_register() returns NULL when CONFIG_PTP_1588_CLOCK is
748 	 * disabled but the driver is still useful without the PTP device
749 	 * as it still handles the ICTIMESYNCFLAG_SYNC case.
750 	 */
751 	hv_ptp_clock = ptp_clock_register(&ptp_hyperv_info, NULL);
752 	if (IS_ERR_OR_NULL(hv_ptp_clock)) {
753 		pr_err("cannot register PTP clock: %d\n",
754 		       PTR_ERR_OR_ZERO(hv_ptp_clock));
755 		hv_ptp_clock = NULL;
756 	}
757 
758 	return 0;
759 }
760 
761 static void hv_timesync_cancel_work(void)
762 {
763 	cancel_work_sync(&adj_time_work);
764 }
765 
766 static int hv_timesync_pre_suspend(void)
767 {
768 	hv_timesync_cancel_work();
769 	return 0;
770 }
771 
772 static void hv_timesync_deinit(void)
773 {
774 	if (hv_ptp_clock)
775 		ptp_clock_unregister(hv_ptp_clock);
776 
777 	hv_timesync_cancel_work();
778 }
779 
780 static int __init init_hyperv_utils(void)
781 {
782 	pr_info("Registering HyperV Utility Driver\n");
783 
784 	return vmbus_driver_register(&util_drv);
785 }
786 
787 static void exit_hyperv_utils(void)
788 {
789 	pr_info("De-Registered HyperV Utility Driver\n");
790 
791 	vmbus_driver_unregister(&util_drv);
792 }
793 
794 module_init(init_hyperv_utils);
795 module_exit(exit_hyperv_utils);
796 
797 MODULE_DESCRIPTION("Hyper-V Utilities");
798 MODULE_LICENSE("GPL");
799