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1// SPDX-License-Identifier: GPL-2.0-only2/*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 ": " fmt10 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	325#define SD_MINOR	026#define SD_MINOR_1	127#define SD_MINOR_2	228#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	133#define SD_VERSION_1	(SD_MAJOR_1 << 16 | SD_MINOR)34 35#define TS_MAJOR	436#define TS_MINOR	037#define TS_VERSION	(TS_MAJOR << 16 | TS_MINOR)38 39#define TS_MAJOR_1	140#define TS_VERSION_1	(TS_MAJOR_1 << 16 | TS_MINOR)41 42#define TS_MAJOR_3	343#define TS_VERSION_3	(TS_MAJOR_3 << 16 | TS_MINOR)44 45#define HB_MAJOR	346#define HB_MINOR	047#define HB_VERSION	(HB_MAJOR << 16 | HB_MINOR)48 49#define HB_MAJOR_1	150#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 457static const int sd_versions[] = {58	SD_VERSION_3_2,59	SD_VERSION_3_1,60	SD_VERSION,61	SD_VERSION_162};63 64#define TS_VER_COUNT 365static const int ts_versions[] = {66	TS_VERSION,67	TS_VERSION_3,68	TS_VERSION_169};70 71#define HB_VER_COUNT 272static const int hb_versions[] = {73	HB_VERSION,74	HB_VERSION_175};76 77#define FW_VER_COUNT 278static const int fw_versions[] = {79	UTIL_FW_VERSION,80	UTIL_WS2K8_FW_VERSION81};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 means229		 * performing the request by force. Linux always tries230		 * 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_TRANSACTION265		| 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 to282 * requests by using this data and the current partition-wide time reference283 * 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 seconds303 */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 host317	 * is older than the max allowable threshold. clock_gettime()318	 * and PTP ioctl do not have a documented error that we could319	 * 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 time372 * message after the timesync channel is opened. Since the hv_utils module is373 * loaded after hv_vmbus, the first message is usually missed. This bit is374 * considered a hard request to discipline the clock.375 *376 * ICTIMESYNCFLAG_SAMPLE bit indicates a time sample from host. This is377 * typically used as a hint to the guest. The guest is under no obligation378 * 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 snapshot387	 * 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-V397	 * clocksource read when the time sample was generated), we can398	 * improve the precision by adding the delta between now and the399	 * time of generation. For older protocols we set400	 * 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 update427	 * host_ts428	 */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_TRANSACTION495			| 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 not552			 * included in the check as the host may not fill it up entirely553			 */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_TRANSACTION569			| 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 performance601	 * critical and do not need batched reading. Furthermore, some services602	 * 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 the604	 * 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 frozen638 * (refer to hibernate() -> freeze_processes()). The userspace is thawed only639 * 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_shutdown678	},679	/* Time synch guid */680	{ HV_TS_GUID,681	  .driver_data = (unsigned long)&util_timesynch682	},683	/* Heartbeat guid */684	{ HV_HEART_BEAT_GUID,685	  .driver_data = (unsigned long)&util_heartbeat686	},687	/* KVP guid */688	{ HV_KVP_GUID,689	  .driver_data = (unsigned long)&util_kvp690	},691	/* VSS GUID */692	{ HV_VSS_GUID,693	  .driver_data = (unsigned long)&util_vss694	},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 is758	 * disabled but the driver is still useful without the PTP device759	 * 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