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