xref: /openbmc/linux/drivers/hv/hv_util.c (revision 96ec2939)
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 
52 static int sd_srv_version;
53 static int ts_srv_version;
54 static int hb_srv_version;
55 
56 #define SD_VER_COUNT 4
57 static 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
65 static const int ts_versions[] = {
66 	TS_VERSION,
67 	TS_VERSION_3,
68 	TS_VERSION_1
69 };
70 
71 #define HB_VER_COUNT 2
72 static const int hb_versions[] = {
73 	HB_VERSION,
74 	HB_VERSION_1
75 };
76 
77 #define FW_VER_COUNT 2
78 static 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  */
86 struct hibernate_work_context {
87 	struct work_struct work;
88 	struct hv_device *dev;
89 };
90 
91 static struct hibernate_work_context hibernate_context;
92 static bool hibernation_supported;
93 
send_hibernate_uevent(struct work_struct * work)94 static 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 
hv_shutdown_init(struct hv_util_service * srv)106 static 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 
118 static void shutdown_onchannelcallback(void *context);
119 static struct hv_util_service util_shutdown = {
120 	.util_cb = shutdown_onchannelcallback,
121 	.util_init = hv_shutdown_init,
122 };
123 
124 static int hv_timesync_init(struct hv_util_service *srv);
125 static int hv_timesync_pre_suspend(void);
126 static void hv_timesync_deinit(void);
127 
128 static void timesync_onchannelcallback(void *context);
129 static 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 
136 static void heartbeat_onchannelcallback(void *context);
137 static struct hv_util_service util_heartbeat = {
138 	.util_cb = heartbeat_onchannelcallback,
139 };
140 
141 static 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 
149 static 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 
157 static struct hv_util_service util_fcopy = {
158 	.util_cb = hv_fcopy_onchannelcallback,
159 	.util_init = hv_fcopy_init,
160 	.util_pre_suspend = hv_fcopy_pre_suspend,
161 	.util_pre_resume = hv_fcopy_pre_resume,
162 	.util_deinit = hv_fcopy_deinit,
163 };
164 
perform_shutdown(struct work_struct * dummy)165 static void perform_shutdown(struct work_struct *dummy)
166 {
167 	orderly_poweroff(true);
168 }
169 
perform_restart(struct work_struct * dummy)170 static void perform_restart(struct work_struct *dummy)
171 {
172 	orderly_reboot();
173 }
174 
175 /*
176  * Perform the shutdown operation in a thread context.
177  */
178 static DECLARE_WORK(shutdown_work, perform_shutdown);
179 
180 /*
181  * Perform the restart operation in a thread context.
182  */
183 static DECLARE_WORK(restart_work, perform_restart);
184 
shutdown_onchannelcallback(void * context)185 static void shutdown_onchannelcallback(void *context)
186 {
187 	struct vmbus_channel *channel = context;
188 	struct work_struct *work = NULL;
189 	u32 recvlen;
190 	u64 requestid;
191 	u8  *shut_txf_buf = util_shutdown.recv_buffer;
192 
193 	struct shutdown_msg_data *shutdown_msg;
194 
195 	struct icmsg_hdr *icmsghdrp;
196 
197 	if (vmbus_recvpacket(channel, shut_txf_buf, HV_HYP_PAGE_SIZE, &recvlen, &requestid)) {
198 		pr_err_ratelimited("Shutdown request received. Could not read into shut txf buf\n");
199 		return;
200 	}
201 
202 	if (!recvlen)
203 		return;
204 
205 	/* Ensure recvlen is big enough to read header data */
206 	if (recvlen < ICMSG_HDR) {
207 		pr_err_ratelimited("Shutdown request received. Packet length too small: %d\n",
208 				   recvlen);
209 		return;
210 	}
211 
212 	icmsghdrp = (struct icmsg_hdr *)&shut_txf_buf[sizeof(struct vmbuspipe_hdr)];
213 
214 	if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) {
215 		if (vmbus_prep_negotiate_resp(icmsghdrp,
216 				shut_txf_buf, recvlen,
217 				fw_versions, FW_VER_COUNT,
218 				sd_versions, SD_VER_COUNT,
219 				NULL, &sd_srv_version)) {
220 			pr_info("Shutdown IC version %d.%d\n",
221 				sd_srv_version >> 16,
222 				sd_srv_version & 0xFFFF);
223 		}
224 	} else if (icmsghdrp->icmsgtype == ICMSGTYPE_SHUTDOWN) {
225 		/* Ensure recvlen is big enough to contain shutdown_msg_data struct */
226 		if (recvlen < ICMSG_HDR + sizeof(struct shutdown_msg_data)) {
227 			pr_err_ratelimited("Invalid shutdown msg data. Packet length too small: %u\n",
228 					   recvlen);
229 			return;
230 		}
231 
232 		shutdown_msg = (struct shutdown_msg_data *)&shut_txf_buf[ICMSG_HDR];
233 
234 		/*
235 		 * shutdown_msg->flags can be 0(shut down), 2(reboot),
236 		 * or 4(hibernate). It may bitwise-OR 1, which means
237 		 * performing the request by force. Linux always tries
238 		 * to perform the request by force.
239 		 */
240 		switch (shutdown_msg->flags) {
241 		case 0:
242 		case 1:
243 			icmsghdrp->status = HV_S_OK;
244 			work = &shutdown_work;
245 			pr_info("Shutdown request received - graceful shutdown initiated\n");
246 			break;
247 		case 2:
248 		case 3:
249 			icmsghdrp->status = HV_S_OK;
250 			work = &restart_work;
251 			pr_info("Restart request received - graceful restart initiated\n");
252 			break;
253 		case 4:
254 		case 5:
255 			pr_info("Hibernation request received\n");
256 			icmsghdrp->status = hibernation_supported ?
257 				HV_S_OK : HV_E_FAIL;
258 			if (hibernation_supported)
259 				work = &hibernate_context.work;
260 			break;
261 		default:
262 			icmsghdrp->status = HV_E_FAIL;
263 			pr_info("Shutdown request received - Invalid request\n");
264 			break;
265 		}
266 	} else {
267 		icmsghdrp->status = HV_E_FAIL;
268 		pr_err_ratelimited("Shutdown request received. Invalid msg type: %d\n",
269 				   icmsghdrp->icmsgtype);
270 	}
271 
272 	icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION
273 		| ICMSGHDRFLAG_RESPONSE;
274 
275 	vmbus_sendpacket(channel, shut_txf_buf,
276 			 recvlen, requestid,
277 			 VM_PKT_DATA_INBAND, 0);
278 
279 	if (work)
280 		schedule_work(work);
281 }
282 
283 /*
284  * Set the host time in a process context.
285  */
286 static struct work_struct adj_time_work;
287 
288 /*
289  * The last time sample, received from the host. PTP device responds to
290  * requests by using this data and the current partition-wide time reference
291  * count.
292  */
293 static struct {
294 	u64				host_time;
295 	u64				ref_time;
296 	spinlock_t			lock;
297 } host_ts;
298 
reftime_to_ns(u64 reftime)299 static inline u64 reftime_to_ns(u64 reftime)
300 {
301 	return (reftime - WLTIMEDELTA) * 100;
302 }
303 
304 /*
305  * Hard coded threshold for host timesync delay: 600 seconds
306  */
307 static const u64 HOST_TIMESYNC_DELAY_THRESH = 600 * (u64)NSEC_PER_SEC;
308 
hv_get_adj_host_time(struct timespec64 * ts)309 static int hv_get_adj_host_time(struct timespec64 *ts)
310 {
311 	u64 newtime, reftime, timediff_adj;
312 	unsigned long flags;
313 	int ret = 0;
314 
315 	spin_lock_irqsave(&host_ts.lock, flags);
316 	reftime = hv_read_reference_counter();
317 
318 	/*
319 	 * We need to let the caller know that last update from host
320 	 * is older than the max allowable threshold. clock_gettime()
321 	 * and PTP ioctl do not have a documented error that we could
322 	 * return for this specific case. Use ESTALE to report this.
323 	 */
324 	timediff_adj = reftime - host_ts.ref_time;
325 	if (timediff_adj * 100 > HOST_TIMESYNC_DELAY_THRESH) {
326 		pr_warn_once("TIMESYNC IC: Stale time stamp, %llu nsecs old\n",
327 			     (timediff_adj * 100));
328 		ret = -ESTALE;
329 	}
330 
331 	newtime = host_ts.host_time + timediff_adj;
332 	*ts = ns_to_timespec64(reftime_to_ns(newtime));
333 	spin_unlock_irqrestore(&host_ts.lock, flags);
334 
335 	return ret;
336 }
337 
hv_set_host_time(struct work_struct * work)338 static void hv_set_host_time(struct work_struct *work)
339 {
340 
341 	struct timespec64 ts;
342 
343 	if (!hv_get_adj_host_time(&ts))
344 		do_settimeofday64(&ts);
345 }
346 
347 /*
348  * Synchronize time with host after reboot, restore, etc.
349  *
350  * ICTIMESYNCFLAG_SYNC flag bit indicates reboot, restore events of the VM.
351  * After reboot the flag ICTIMESYNCFLAG_SYNC is included in the first time
352  * message after the timesync channel is opened. Since the hv_utils module is
353  * loaded after hv_vmbus, the first message is usually missed. This bit is
354  * considered a hard request to discipline the clock.
355  *
356  * ICTIMESYNCFLAG_SAMPLE bit indicates a time sample from host. This is
357  * typically used as a hint to the guest. The guest is under no obligation
358  * to discipline the clock.
359  */
adj_guesttime(u64 hosttime,u64 reftime,u8 adj_flags)360 static inline void adj_guesttime(u64 hosttime, u64 reftime, u8 adj_flags)
361 {
362 	unsigned long flags;
363 	u64 cur_reftime;
364 
365 	/*
366 	 * Save the adjusted time sample from the host and the snapshot
367 	 * of the current system time.
368 	 */
369 	spin_lock_irqsave(&host_ts.lock, flags);
370 
371 	cur_reftime = hv_read_reference_counter();
372 	host_ts.host_time = hosttime;
373 	host_ts.ref_time = cur_reftime;
374 
375 	/*
376 	 * TimeSync v4 messages contain reference time (guest's Hyper-V
377 	 * clocksource read when the time sample was generated), we can
378 	 * improve the precision by adding the delta between now and the
379 	 * time of generation. For older protocols we set
380 	 * reftime == cur_reftime on call.
381 	 */
382 	host_ts.host_time += (cur_reftime - reftime);
383 
384 	spin_unlock_irqrestore(&host_ts.lock, flags);
385 
386 	/* Schedule work to do do_settimeofday64() */
387 	if (adj_flags & ICTIMESYNCFLAG_SYNC)
388 		schedule_work(&adj_time_work);
389 }
390 
391 /*
392  * Time Sync Channel message handler.
393  */
timesync_onchannelcallback(void * context)394 static void timesync_onchannelcallback(void *context)
395 {
396 	struct vmbus_channel *channel = context;
397 	u32 recvlen;
398 	u64 requestid;
399 	struct icmsg_hdr *icmsghdrp;
400 	struct ictimesync_data *timedatap;
401 	struct ictimesync_ref_data *refdata;
402 	u8 *time_txf_buf = util_timesynch.recv_buffer;
403 
404 	/*
405 	 * Drain the ring buffer and use the last packet to update
406 	 * host_ts
407 	 */
408 	while (1) {
409 		int ret = vmbus_recvpacket(channel, time_txf_buf,
410 					   HV_HYP_PAGE_SIZE, &recvlen,
411 					   &requestid);
412 		if (ret) {
413 			pr_err_ratelimited("TimeSync IC pkt recv failed (Err: %d)\n",
414 					   ret);
415 			break;
416 		}
417 
418 		if (!recvlen)
419 			break;
420 
421 		/* Ensure recvlen is big enough to read header data */
422 		if (recvlen < ICMSG_HDR) {
423 			pr_err_ratelimited("Timesync request received. Packet length too small: %d\n",
424 					   recvlen);
425 			break;
426 		}
427 
428 		icmsghdrp = (struct icmsg_hdr *)&time_txf_buf[
429 				sizeof(struct vmbuspipe_hdr)];
430 
431 		if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) {
432 			if (vmbus_prep_negotiate_resp(icmsghdrp,
433 						time_txf_buf, recvlen,
434 						fw_versions, FW_VER_COUNT,
435 						ts_versions, TS_VER_COUNT,
436 						NULL, &ts_srv_version)) {
437 				pr_info("TimeSync IC version %d.%d\n",
438 					ts_srv_version >> 16,
439 					ts_srv_version & 0xFFFF);
440 			}
441 		} else if (icmsghdrp->icmsgtype == ICMSGTYPE_TIMESYNC) {
442 			if (ts_srv_version > TS_VERSION_3) {
443 				/* Ensure recvlen is big enough to read ictimesync_ref_data */
444 				if (recvlen < ICMSG_HDR + sizeof(struct ictimesync_ref_data)) {
445 					pr_err_ratelimited("Invalid ictimesync ref data. Length too small: %u\n",
446 							   recvlen);
447 					break;
448 				}
449 				refdata = (struct ictimesync_ref_data *)&time_txf_buf[ICMSG_HDR];
450 
451 				adj_guesttime(refdata->parenttime,
452 						refdata->vmreferencetime,
453 						refdata->flags);
454 			} else {
455 				/* Ensure recvlen is big enough to read ictimesync_data */
456 				if (recvlen < ICMSG_HDR + sizeof(struct ictimesync_data)) {
457 					pr_err_ratelimited("Invalid ictimesync data. Length too small: %u\n",
458 							   recvlen);
459 					break;
460 				}
461 				timedatap = (struct ictimesync_data *)&time_txf_buf[ICMSG_HDR];
462 
463 				adj_guesttime(timedatap->parenttime,
464 					      hv_read_reference_counter(),
465 					      timedatap->flags);
466 			}
467 		} else {
468 			icmsghdrp->status = HV_E_FAIL;
469 			pr_err_ratelimited("Timesync request received. Invalid msg type: %d\n",
470 					   icmsghdrp->icmsgtype);
471 		}
472 
473 		icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION
474 			| ICMSGHDRFLAG_RESPONSE;
475 
476 		vmbus_sendpacket(channel, time_txf_buf,
477 				 recvlen, requestid,
478 				 VM_PKT_DATA_INBAND, 0);
479 	}
480 }
481 
482 /*
483  * Heartbeat functionality.
484  * Every two seconds, Hyper-V send us a heartbeat request message.
485  * we respond to this message, and Hyper-V knows we are alive.
486  */
heartbeat_onchannelcallback(void * context)487 static void heartbeat_onchannelcallback(void *context)
488 {
489 	struct vmbus_channel *channel = context;
490 	u32 recvlen;
491 	u64 requestid;
492 	struct icmsg_hdr *icmsghdrp;
493 	struct heartbeat_msg_data *heartbeat_msg;
494 	u8 *hbeat_txf_buf = util_heartbeat.recv_buffer;
495 
496 	while (1) {
497 
498 		if (vmbus_recvpacket(channel, hbeat_txf_buf, HV_HYP_PAGE_SIZE,
499 				     &recvlen, &requestid)) {
500 			pr_err_ratelimited("Heartbeat request received. Could not read into hbeat txf buf\n");
501 			return;
502 		}
503 
504 		if (!recvlen)
505 			break;
506 
507 		/* Ensure recvlen is big enough to read header data */
508 		if (recvlen < ICMSG_HDR) {
509 			pr_err_ratelimited("Heartbeat request received. Packet length too small: %d\n",
510 					   recvlen);
511 			break;
512 		}
513 
514 		icmsghdrp = (struct icmsg_hdr *)&hbeat_txf_buf[
515 				sizeof(struct vmbuspipe_hdr)];
516 
517 		if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) {
518 			if (vmbus_prep_negotiate_resp(icmsghdrp,
519 					hbeat_txf_buf, recvlen,
520 					fw_versions, FW_VER_COUNT,
521 					hb_versions, HB_VER_COUNT,
522 					NULL, &hb_srv_version)) {
523 
524 				pr_info("Heartbeat IC version %d.%d\n",
525 					hb_srv_version >> 16,
526 					hb_srv_version & 0xFFFF);
527 			}
528 		} else if (icmsghdrp->icmsgtype == ICMSGTYPE_HEARTBEAT) {
529 			/*
530 			 * Ensure recvlen is big enough to read seq_num. Reserved area is not
531 			 * included in the check as the host may not fill it up entirely
532 			 */
533 			if (recvlen < ICMSG_HDR + sizeof(u64)) {
534 				pr_err_ratelimited("Invalid heartbeat msg data. Length too small: %u\n",
535 						   recvlen);
536 				break;
537 			}
538 			heartbeat_msg = (struct heartbeat_msg_data *)&hbeat_txf_buf[ICMSG_HDR];
539 
540 			heartbeat_msg->seq_num += 1;
541 		} else {
542 			icmsghdrp->status = HV_E_FAIL;
543 			pr_err_ratelimited("Heartbeat request received. Invalid msg type: %d\n",
544 					   icmsghdrp->icmsgtype);
545 		}
546 
547 		icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION
548 			| ICMSGHDRFLAG_RESPONSE;
549 
550 		vmbus_sendpacket(channel, hbeat_txf_buf,
551 				 recvlen, requestid,
552 				 VM_PKT_DATA_INBAND, 0);
553 	}
554 }
555 
556 #define HV_UTIL_RING_SEND_SIZE VMBUS_RING_SIZE(3 * HV_HYP_PAGE_SIZE)
557 #define HV_UTIL_RING_RECV_SIZE VMBUS_RING_SIZE(3 * HV_HYP_PAGE_SIZE)
558 
util_probe(struct hv_device * dev,const struct hv_vmbus_device_id * dev_id)559 static int util_probe(struct hv_device *dev,
560 			const struct hv_vmbus_device_id *dev_id)
561 {
562 	struct hv_util_service *srv =
563 		(struct hv_util_service *)dev_id->driver_data;
564 	int ret;
565 
566 	srv->recv_buffer = kmalloc(HV_HYP_PAGE_SIZE * 4, GFP_KERNEL);
567 	if (!srv->recv_buffer)
568 		return -ENOMEM;
569 	srv->channel = dev->channel;
570 	if (srv->util_init) {
571 		ret = srv->util_init(srv);
572 		if (ret) {
573 			ret = -ENODEV;
574 			goto error1;
575 		}
576 	}
577 
578 	/*
579 	 * The set of services managed by the util driver are not performance
580 	 * critical and do not need batched reading. Furthermore, some services
581 	 * such as KVP can only handle one message from the host at a time.
582 	 * Turn off batched reading for all util drivers before we open the
583 	 * channel.
584 	 */
585 	set_channel_read_mode(dev->channel, HV_CALL_DIRECT);
586 
587 	hv_set_drvdata(dev, srv);
588 
589 	ret = vmbus_open(dev->channel, HV_UTIL_RING_SEND_SIZE,
590 			 HV_UTIL_RING_RECV_SIZE, NULL, 0, srv->util_cb,
591 			 dev->channel);
592 	if (ret)
593 		goto error;
594 
595 	return 0;
596 
597 error:
598 	if (srv->util_deinit)
599 		srv->util_deinit();
600 error1:
601 	kfree(srv->recv_buffer);
602 	return ret;
603 }
604 
util_remove(struct hv_device * dev)605 static void util_remove(struct hv_device *dev)
606 {
607 	struct hv_util_service *srv = hv_get_drvdata(dev);
608 
609 	if (srv->util_deinit)
610 		srv->util_deinit();
611 	vmbus_close(dev->channel);
612 	kfree(srv->recv_buffer);
613 }
614 
615 /*
616  * When we're in util_suspend(), all the userspace processes have been frozen
617  * (refer to hibernate() -> freeze_processes()). The userspace is thawed only
618  * after the whole resume procedure, including util_resume(), finishes.
619  */
util_suspend(struct hv_device * dev)620 static int util_suspend(struct hv_device *dev)
621 {
622 	struct hv_util_service *srv = hv_get_drvdata(dev);
623 	int ret = 0;
624 
625 	if (srv->util_pre_suspend) {
626 		ret = srv->util_pre_suspend();
627 		if (ret)
628 			return ret;
629 	}
630 
631 	vmbus_close(dev->channel);
632 
633 	return 0;
634 }
635 
util_resume(struct hv_device * dev)636 static int util_resume(struct hv_device *dev)
637 {
638 	struct hv_util_service *srv = hv_get_drvdata(dev);
639 	int ret = 0;
640 
641 	if (srv->util_pre_resume) {
642 		ret = srv->util_pre_resume();
643 		if (ret)
644 			return ret;
645 	}
646 
647 	ret = vmbus_open(dev->channel, HV_UTIL_RING_SEND_SIZE,
648 			 HV_UTIL_RING_RECV_SIZE, NULL, 0, srv->util_cb,
649 			 dev->channel);
650 	return ret;
651 }
652 
653 static const struct hv_vmbus_device_id id_table[] = {
654 	/* Shutdown guid */
655 	{ HV_SHUTDOWN_GUID,
656 	  .driver_data = (unsigned long)&util_shutdown
657 	},
658 	/* Time synch guid */
659 	{ HV_TS_GUID,
660 	  .driver_data = (unsigned long)&util_timesynch
661 	},
662 	/* Heartbeat guid */
663 	{ HV_HEART_BEAT_GUID,
664 	  .driver_data = (unsigned long)&util_heartbeat
665 	},
666 	/* KVP guid */
667 	{ HV_KVP_GUID,
668 	  .driver_data = (unsigned long)&util_kvp
669 	},
670 	/* VSS GUID */
671 	{ HV_VSS_GUID,
672 	  .driver_data = (unsigned long)&util_vss
673 	},
674 	/* File copy GUID */
675 	{ HV_FCOPY_GUID,
676 	  .driver_data = (unsigned long)&util_fcopy
677 	},
678 	{ },
679 };
680 
681 MODULE_DEVICE_TABLE(vmbus, id_table);
682 
683 /* The one and only one */
684 static  struct hv_driver util_drv = {
685 	.name = "hv_utils",
686 	.id_table = id_table,
687 	.probe =  util_probe,
688 	.remove =  util_remove,
689 	.suspend = util_suspend,
690 	.resume =  util_resume,
691 	.driver = {
692 		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
693 	},
694 };
695 
hv_ptp_enable(struct ptp_clock_info * info,struct ptp_clock_request * request,int on)696 static int hv_ptp_enable(struct ptp_clock_info *info,
697 			 struct ptp_clock_request *request, int on)
698 {
699 	return -EOPNOTSUPP;
700 }
701 
hv_ptp_settime(struct ptp_clock_info * p,const struct timespec64 * ts)702 static int hv_ptp_settime(struct ptp_clock_info *p, const struct timespec64 *ts)
703 {
704 	return -EOPNOTSUPP;
705 }
706 
hv_ptp_adjfine(struct ptp_clock_info * ptp,long delta)707 static int hv_ptp_adjfine(struct ptp_clock_info *ptp, long delta)
708 {
709 	return -EOPNOTSUPP;
710 }
hv_ptp_adjtime(struct ptp_clock_info * ptp,s64 delta)711 static int hv_ptp_adjtime(struct ptp_clock_info *ptp, s64 delta)
712 {
713 	return -EOPNOTSUPP;
714 }
715 
hv_ptp_gettime(struct ptp_clock_info * info,struct timespec64 * ts)716 static int hv_ptp_gettime(struct ptp_clock_info *info, struct timespec64 *ts)
717 {
718 	return hv_get_adj_host_time(ts);
719 }
720 
721 static struct ptp_clock_info ptp_hyperv_info = {
722 	.name		= "hyperv",
723 	.enable         = hv_ptp_enable,
724 	.adjtime        = hv_ptp_adjtime,
725 	.adjfine        = hv_ptp_adjfine,
726 	.gettime64      = hv_ptp_gettime,
727 	.settime64      = hv_ptp_settime,
728 	.owner		= THIS_MODULE,
729 };
730 
731 static struct ptp_clock *hv_ptp_clock;
732 
hv_timesync_init(struct hv_util_service * srv)733 static int hv_timesync_init(struct hv_util_service *srv)
734 {
735 	spin_lock_init(&host_ts.lock);
736 
737 	INIT_WORK(&adj_time_work, hv_set_host_time);
738 
739 	/*
740 	 * ptp_clock_register() returns NULL when CONFIG_PTP_1588_CLOCK is
741 	 * disabled but the driver is still useful without the PTP device
742 	 * as it still handles the ICTIMESYNCFLAG_SYNC case.
743 	 */
744 	hv_ptp_clock = ptp_clock_register(&ptp_hyperv_info, NULL);
745 	if (IS_ERR_OR_NULL(hv_ptp_clock)) {
746 		pr_err("cannot register PTP clock: %d\n",
747 		       PTR_ERR_OR_ZERO(hv_ptp_clock));
748 		hv_ptp_clock = NULL;
749 	}
750 
751 	return 0;
752 }
753 
hv_timesync_cancel_work(void)754 static void hv_timesync_cancel_work(void)
755 {
756 	cancel_work_sync(&adj_time_work);
757 }
758 
hv_timesync_pre_suspend(void)759 static int hv_timesync_pre_suspend(void)
760 {
761 	hv_timesync_cancel_work();
762 	return 0;
763 }
764 
hv_timesync_deinit(void)765 static void hv_timesync_deinit(void)
766 {
767 	if (hv_ptp_clock)
768 		ptp_clock_unregister(hv_ptp_clock);
769 
770 	hv_timesync_cancel_work();
771 }
772 
init_hyperv_utils(void)773 static int __init init_hyperv_utils(void)
774 {
775 	pr_info("Registering HyperV Utility Driver\n");
776 
777 	return vmbus_driver_register(&util_drv);
778 }
779 
exit_hyperv_utils(void)780 static void exit_hyperv_utils(void)
781 {
782 	pr_info("De-Registered HyperV Utility Driver\n");
783 
784 	vmbus_driver_unregister(&util_drv);
785 }
786 
787 module_init(init_hyperv_utils);
788 module_exit(exit_hyperv_utils);
789 
790 MODULE_DESCRIPTION("Hyper-V Utilities");
791 MODULE_LICENSE("GPL");
792