1/*
2 * Copyright (c) 2010, Microsoft Corporation.
3 *
4 * This program is free software; you can redistribute it and/or modify it
5 * under the terms and conditions of the GNU General Public License,
6 * version 2, as published by the Free Software Foundation.
7 *
8 * This program is distributed in the hope it will be useful, but WITHOUT
9 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
10 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
11 * more details.
12 *
13 * You should have received a copy of the GNU General Public License along with
14 * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
15 * Place - Suite 330, Boston, MA 02111-1307 USA.
16 *
17 * Authors:
18 * Haiyang Zhang <haiyangz@microsoft.com>
19 * Hank Janssen <hjanssen@microsoft.com>
20 */
21#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
22
23#include <linux/kernel.h>
24#include <linux/init.h>
25#include <linux/module.h>
26#include <linux/slab.h>
27#include <linux/sysctl.h>
28#include <linux/reboot.h>
29#include <linux/hyperv.h>
30#include <linux/clockchips.h>
31#include <linux/ptp_clock_kernel.h>
32#include <asm/mshyperv.h>
33
34#include "hyperv_vmbus.h"
35
36#define SD_MAJOR 3
37#define SD_MINOR 0
38#define SD_VERSION (SD_MAJOR << 16 | SD_MINOR)
39
40#define SD_MAJOR_1 1
41#define SD_VERSION_1 (SD_MAJOR_1 << 16 | SD_MINOR)
42
43#define TS_MAJOR 4
44#define TS_MINOR 0
45#define TS_VERSION (TS_MAJOR << 16 | TS_MINOR)
46
47#define TS_MAJOR_1 1
48#define TS_VERSION_1 (TS_MAJOR_1 << 16 | TS_MINOR)
49
50#define TS_MAJOR_3 3
51#define TS_VERSION_3 (TS_MAJOR_3 << 16 | TS_MINOR)
52
53#define HB_MAJOR 3
54#define HB_MINOR 0
55#define HB_VERSION (HB_MAJOR << 16 | HB_MINOR)
56
57#define HB_MAJOR_1 1
58#define HB_VERSION_1 (HB_MAJOR_1 << 16 | HB_MINOR)
59
60static int sd_srv_version;
61static int ts_srv_version;
62static int hb_srv_version;
63
64#define SD_VER_COUNT 2
65static const int sd_versions[] = {
66 SD_VERSION,
67 SD_VERSION_1
68};
69
70#define TS_VER_COUNT 3
71static const int ts_versions[] = {
72 TS_VERSION,
73 TS_VERSION_3,
74 TS_VERSION_1
75};
76
77#define HB_VER_COUNT 2
78static const int hb_versions[] = {
79 HB_VERSION,
80 HB_VERSION_1
81};
82
83#define FW_VER_COUNT 2
84static const int fw_versions[] = {
85 UTIL_FW_VERSION,
86 UTIL_WS2K8_FW_VERSION
87};
88
89static void shutdown_onchannelcallback(void *context);
90static struct hv_util_service util_shutdown = {
91 .util_cb = shutdown_onchannelcallback,
92};
93
94static int hv_timesync_init(struct hv_util_service *srv);
95static void hv_timesync_deinit(void);
96
97static void timesync_onchannelcallback(void *context);
98static struct hv_util_service util_timesynch = {
99 .util_cb = timesync_onchannelcallback,
100 .util_init = hv_timesync_init,
101 .util_deinit = hv_timesync_deinit,
102};
103
104static void heartbeat_onchannelcallback(void *context);
105static struct hv_util_service util_heartbeat = {
106 .util_cb = heartbeat_onchannelcallback,
107};
108
109static struct hv_util_service util_kvp = {
110 .util_cb = hv_kvp_onchannelcallback,
111 .util_init = hv_kvp_init,
112 .util_deinit = hv_kvp_deinit,
113};
114
115static struct hv_util_service util_vss = {
116 .util_cb = hv_vss_onchannelcallback,
117 .util_init = hv_vss_init,
118 .util_deinit = hv_vss_deinit,
119};
120
121static struct hv_util_service util_fcopy = {
122 .util_cb = hv_fcopy_onchannelcallback,
123 .util_init = hv_fcopy_init,
124 .util_deinit = hv_fcopy_deinit,
125};
126
127static void perform_shutdown(struct work_struct *dummy)
128{
129 orderly_poweroff(true);
130}
131
132/*
133 * Perform the shutdown operation in a thread context.
134 */
135static DECLARE_WORK(shutdown_work, perform_shutdown);
136
137static void shutdown_onchannelcallback(void *context)
138{
139 struct vmbus_channel *channel = context;
140 u32 recvlen;
141 u64 requestid;
142 bool execute_shutdown = false;
143 u8 *shut_txf_buf = util_shutdown.recv_buffer;
144
145 struct shutdown_msg_data *shutdown_msg;
146
147 struct icmsg_hdr *icmsghdrp;
148
149 vmbus_recvpacket(channel, shut_txf_buf,
150 PAGE_SIZE, &recvlen, &requestid);
151
152 if (recvlen > 0) {
153 icmsghdrp = (struct icmsg_hdr *)&shut_txf_buf[
154 sizeof(struct vmbuspipe_hdr)];
155
156 if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) {
157 if (vmbus_prep_negotiate_resp(icmsghdrp, shut_txf_buf,
158 fw_versions, FW_VER_COUNT,
159 sd_versions, SD_VER_COUNT,
160 NULL, &sd_srv_version)) {
161 pr_info("Shutdown IC version %d.%d\n",
162 sd_srv_version >> 16,
163 sd_srv_version & 0xFFFF);
164 }
165 } else {
166 shutdown_msg =
167 (struct shutdown_msg_data *)&shut_txf_buf[
168 sizeof(struct vmbuspipe_hdr) +
169 sizeof(struct icmsg_hdr)];
170
171 switch (shutdown_msg->flags) {
172 case 0:
173 case 1:
174 icmsghdrp->status = HV_S_OK;
175 execute_shutdown = true;
176
177 pr_info("Shutdown request received -"
178 " graceful shutdown initiated\n");
179 break;
180 default:
181 icmsghdrp->status = HV_E_FAIL;
182 execute_shutdown = false;
183
184 pr_info("Shutdown request received -"
185 " Invalid request\n");
186 break;
187 }
188 }
189
190 icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION
191 | ICMSGHDRFLAG_RESPONSE;
192
193 vmbus_sendpacket(channel, shut_txf_buf,
194 recvlen, requestid,
195 VM_PKT_DATA_INBAND, 0);
196 }
197
198 if (execute_shutdown == true)
199 schedule_work(&shutdown_work);
200}
201
202/*
203 * Set the host time in a process context.
204 */
205static struct work_struct adj_time_work;
206
207/*
208 * The last time sample, received from the host. PTP device responds to
209 * requests by using this data and the current partition-wide time reference
210 * count.
211 */
212static struct {
213 u64 host_time;
214 u64 ref_time;
215 spinlock_t lock;
216} host_ts;
217
218static struct timespec64 hv_get_adj_host_time(void)
219{
220 struct timespec64 ts;
221 u64 newtime, reftime;
222 unsigned long flags;
223
224 spin_lock_irqsave(&host_ts.lock, flags);
225 reftime = hyperv_cs->read(hyperv_cs);
226 newtime = host_ts.host_time + (reftime - host_ts.ref_time);
227 ts = ns_to_timespec64((newtime - WLTIMEDELTA) * 100);
228 spin_unlock_irqrestore(&host_ts.lock, flags);
229
230 return ts;
231}
232
233static void hv_set_host_time(struct work_struct *work)
234{
235 struct timespec64 ts = hv_get_adj_host_time();
236
237 do_settimeofday64(&ts);
238}
239
240/*
241 * Synchronize time with host after reboot, restore, etc.
242 *
243 * ICTIMESYNCFLAG_SYNC flag bit indicates reboot, restore events of the VM.
244 * After reboot the flag ICTIMESYNCFLAG_SYNC is included in the first time
245 * message after the timesync channel is opened. Since the hv_utils module is
246 * loaded after hv_vmbus, the first message is usually missed. This bit is
247 * considered a hard request to discipline the clock.
248 *
249 * ICTIMESYNCFLAG_SAMPLE bit indicates a time sample from host. This is
250 * typically used as a hint to the guest. The guest is under no obligation
251 * to discipline the clock.
252 */
253static inline void adj_guesttime(u64 hosttime, u64 reftime, u8 adj_flags)
254{
255 unsigned long flags;
256 u64 cur_reftime;
257
258 /*
259 * Save the adjusted time sample from the host and the snapshot
260 * of the current system time.
261 */
262 spin_lock_irqsave(&host_ts.lock, flags);
263
264 cur_reftime = hyperv_cs->read(hyperv_cs);
265 host_ts.host_time = hosttime;
266 host_ts.ref_time = cur_reftime;
267
268 /*
269 * TimeSync v4 messages contain reference time (guest's Hyper-V
270 * clocksource read when the time sample was generated), we can
271 * improve the precision by adding the delta between now and the
272 * time of generation. For older protocols we set
273 * reftime == cur_reftime on call.
274 */
275 host_ts.host_time += (cur_reftime - reftime);
276
277 spin_unlock_irqrestore(&host_ts.lock, flags);
278
279 /* Schedule work to do do_settimeofday64() */
280 if (adj_flags & ICTIMESYNCFLAG_SYNC)
281 schedule_work(&adj_time_work);
282}
283
284/*
285 * Time Sync Channel message handler.
286 */
287static void timesync_onchannelcallback(void *context)
288{
289 struct vmbus_channel *channel = context;
290 u32 recvlen;
291 u64 requestid;
292 struct icmsg_hdr *icmsghdrp;
293 struct ictimesync_data *timedatap;
294 struct ictimesync_ref_data *refdata;
295 u8 *time_txf_buf = util_timesynch.recv_buffer;
296
297 vmbus_recvpacket(channel, time_txf_buf,
298 PAGE_SIZE, &recvlen, &requestid);
299
300 if (recvlen > 0) {
301 icmsghdrp = (struct icmsg_hdr *)&time_txf_buf[
302 sizeof(struct vmbuspipe_hdr)];
303
304 if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) {
305 if (vmbus_prep_negotiate_resp(icmsghdrp, time_txf_buf,
306 fw_versions, FW_VER_COUNT,
307 ts_versions, TS_VER_COUNT,
308 NULL, &ts_srv_version)) {
309 pr_info("TimeSync IC version %d.%d\n",
310 ts_srv_version >> 16,
311 ts_srv_version & 0xFFFF);
312 }
313 } else {
314 if (ts_srv_version > TS_VERSION_3) {
315 refdata = (struct ictimesync_ref_data *)
316 &time_txf_buf[
317 sizeof(struct vmbuspipe_hdr) +
318 sizeof(struct icmsg_hdr)];
319
320 adj_guesttime(refdata->parenttime,
321 refdata->vmreferencetime,
322 refdata->flags);
323 } else {
324 timedatap = (struct ictimesync_data *)
325 &time_txf_buf[
326 sizeof(struct vmbuspipe_hdr) +
327 sizeof(struct icmsg_hdr)];
328 adj_guesttime(timedatap->parenttime,
329 hyperv_cs->read(hyperv_cs),
330 timedatap->flags);
331 }
332 }
333
334 icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION
335 | ICMSGHDRFLAG_RESPONSE;
336
337 vmbus_sendpacket(channel, time_txf_buf,
338 recvlen, requestid,
339 VM_PKT_DATA_INBAND, 0);
340 }
341}
342
343/*
344 * Heartbeat functionality.
345 * Every two seconds, Hyper-V send us a heartbeat request message.
346 * we respond to this message, and Hyper-V knows we are alive.
347 */
348static void heartbeat_onchannelcallback(void *context)
349{
350 struct vmbus_channel *channel = context;
351 u32 recvlen;
352 u64 requestid;
353 struct icmsg_hdr *icmsghdrp;
354 struct heartbeat_msg_data *heartbeat_msg;
355 u8 *hbeat_txf_buf = util_heartbeat.recv_buffer;
356
357 while (1) {
358
359 vmbus_recvpacket(channel, hbeat_txf_buf,
360 PAGE_SIZE, &recvlen, &requestid);
361
362 if (!recvlen)
363 break;
364
365 icmsghdrp = (struct icmsg_hdr *)&hbeat_txf_buf[
366 sizeof(struct vmbuspipe_hdr)];
367
368 if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) {
369 if (vmbus_prep_negotiate_resp(icmsghdrp,
370 hbeat_txf_buf,
371 fw_versions, FW_VER_COUNT,
372 hb_versions, HB_VER_COUNT,
373 NULL, &hb_srv_version)) {
374
375 pr_info("Heartbeat IC version %d.%d\n",
376 hb_srv_version >> 16,
377 hb_srv_version & 0xFFFF);
378 }
379 } else {
380 heartbeat_msg =
381 (struct heartbeat_msg_data *)&hbeat_txf_buf[
382 sizeof(struct vmbuspipe_hdr) +
383 sizeof(struct icmsg_hdr)];
384
385 heartbeat_msg->seq_num += 1;
386 }
387
388 icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION
389 | ICMSGHDRFLAG_RESPONSE;
390
391 vmbus_sendpacket(channel, hbeat_txf_buf,
392 recvlen, requestid,
393 VM_PKT_DATA_INBAND, 0);
394 }
395}
396
397static int util_probe(struct hv_device *dev,
398 const struct hv_vmbus_device_id *dev_id)
399{
400 struct hv_util_service *srv =
401 (struct hv_util_service *)dev_id->driver_data;
402 int ret;
403
404 srv->recv_buffer = kmalloc(PAGE_SIZE * 4, GFP_KERNEL);
405 if (!srv->recv_buffer)
406 return -ENOMEM;
407 srv->channel = dev->channel;
408 if (srv->util_init) {
409 ret = srv->util_init(srv);
410 if (ret) {
411 ret = -ENODEV;
412 goto error1;
413 }
414 }
415
416 /*
417 * The set of services managed by the util driver are not performance
418 * critical and do not need batched reading. Furthermore, some services
419 * such as KVP can only handle one message from the host at a time.
420 * Turn off batched reading for all util drivers before we open the
421 * channel.
422 */
423 set_channel_read_mode(dev->channel, HV_CALL_DIRECT);
424
425 hv_set_drvdata(dev, srv);
426
427 ret = vmbus_open(dev->channel, 4 * PAGE_SIZE, 4 * PAGE_SIZE, NULL, 0,
428 srv->util_cb, dev->channel);
429 if (ret)
430 goto error;
431
432 return 0;
433
434error:
435 if (srv->util_deinit)
436 srv->util_deinit();
437error1:
438 kfree(srv->recv_buffer);
439 return ret;
440}
441
442static int util_remove(struct hv_device *dev)
443{
444 struct hv_util_service *srv = hv_get_drvdata(dev);
445
446 if (srv->util_deinit)
447 srv->util_deinit();
448 vmbus_close(dev->channel);
449 kfree(srv->recv_buffer);
450
451 return 0;
452}
453
454static const struct hv_vmbus_device_id id_table[] = {
455 /* Shutdown guid */
456 { HV_SHUTDOWN_GUID,
457 .driver_data = (unsigned long)&util_shutdown
458 },
459 /* Time synch guid */
460 { HV_TS_GUID,
461 .driver_data = (unsigned long)&util_timesynch
462 },
463 /* Heartbeat guid */
464 { HV_HEART_BEAT_GUID,
465 .driver_data = (unsigned long)&util_heartbeat
466 },
467 /* KVP guid */
468 { HV_KVP_GUID,
469 .driver_data = (unsigned long)&util_kvp
470 },
471 /* VSS GUID */
472 { HV_VSS_GUID,
473 .driver_data = (unsigned long)&util_vss
474 },
475 /* File copy GUID */
476 { HV_FCOPY_GUID,
477 .driver_data = (unsigned long)&util_fcopy
478 },
479 { },
480};
481
482MODULE_DEVICE_TABLE(vmbus, id_table);
483
484/* The one and only one */
485static struct hv_driver util_drv = {
486 .name = "hv_utils",
487 .id_table = id_table,
488 .probe = util_probe,
489 .remove = util_remove,
490 .driver = {
491 .probe_type = PROBE_PREFER_ASYNCHRONOUS,
492 },
493};
494
495static int hv_ptp_enable(struct ptp_clock_info *info,
496 struct ptp_clock_request *request, int on)
497{
498 return -EOPNOTSUPP;
499}
500
501static int hv_ptp_settime(struct ptp_clock_info *p, const struct timespec64 *ts)
502{
503 return -EOPNOTSUPP;
504}
505
506static int hv_ptp_adjfreq(struct ptp_clock_info *ptp, s32 delta)
507{
508 return -EOPNOTSUPP;
509}
510static int hv_ptp_adjtime(struct ptp_clock_info *ptp, s64 delta)
511{
512 return -EOPNOTSUPP;
513}
514
515static int hv_ptp_gettime(struct ptp_clock_info *info, struct timespec64 *ts)
516{
517 *ts = hv_get_adj_host_time();
518
519 return 0;
520}
521
522static struct ptp_clock_info ptp_hyperv_info = {
523 .name = "hyperv",
524 .enable = hv_ptp_enable,
525 .adjtime = hv_ptp_adjtime,
526 .adjfreq = hv_ptp_adjfreq,
527 .gettime64 = hv_ptp_gettime,
528 .settime64 = hv_ptp_settime,
529 .owner = THIS_MODULE,
530};
531
532static struct ptp_clock *hv_ptp_clock;
533
534static int hv_timesync_init(struct hv_util_service *srv)
535{
536 /* TimeSync requires Hyper-V clocksource. */
537 if (!hyperv_cs)
538 return -ENODEV;
539
540 spin_lock_init(&host_ts.lock);
541
542 INIT_WORK(&adj_time_work, hv_set_host_time);
543
544 /*
545 * ptp_clock_register() returns NULL when CONFIG_PTP_1588_CLOCK is
546 * disabled but the driver is still useful without the PTP device
547 * as it still handles the ICTIMESYNCFLAG_SYNC case.
548 */
549 hv_ptp_clock = ptp_clock_register(&ptp_hyperv_info, NULL);
550 if (IS_ERR_OR_NULL(hv_ptp_clock)) {
551 pr_err("cannot register PTP clock: %ld\n",
552 PTR_ERR(hv_ptp_clock));
553 hv_ptp_clock = NULL;
554 }
555
556 return 0;
557}
558
559static void hv_timesync_deinit(void)
560{
561 if (hv_ptp_clock)
562 ptp_clock_unregister(hv_ptp_clock);
563 cancel_work_sync(&adj_time_work);
564}
565
566static int __init init_hyperv_utils(void)
567{
568 pr_info("Registering HyperV Utility Driver\n");
569
570 return vmbus_driver_register(&util_drv);
571}
572
573static void exit_hyperv_utils(void)
574{
575 pr_info("De-Registered HyperV Utility Driver\n");
576
577 vmbus_driver_unregister(&util_drv);
578}
579
580module_init(init_hyperv_utils);
581module_exit(exit_hyperv_utils);
582
583MODULE_DESCRIPTION("Hyper-V Utilities");
584MODULE_LICENSE("GPL");
585