xref: /linux/drivers/hv/hv_util.c (revision c4ee0af3fa0dc65f690fc908f02b8355f9576ea0)
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 
31 
32 #define SD_MAJOR	3
33 #define SD_MINOR	0
34 #define SD_VERSION	(SD_MAJOR << 16 | SD_MINOR)
35 
36 #define SD_WS2008_MAJOR		1
37 #define SD_WS2008_VERSION	(SD_WS2008_MAJOR << 16 | SD_MINOR)
38 
39 #define TS_MAJOR	3
40 #define TS_MINOR	0
41 #define TS_VERSION	(TS_MAJOR << 16 | TS_MINOR)
42 
43 #define TS_WS2008_MAJOR		1
44 #define TS_WS2008_VERSION	(TS_WS2008_MAJOR << 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_WS2008_MAJOR	1
51 #define HB_WS2008_VERSION	(HB_WS2008_MAJOR << 16 | HB_MINOR)
52 
53 static int sd_srv_version;
54 static int ts_srv_version;
55 static int hb_srv_version;
56 static int util_fw_version;
57 
58 static void shutdown_onchannelcallback(void *context);
59 static struct hv_util_service util_shutdown = {
60 	.util_cb = shutdown_onchannelcallback,
61 };
62 
63 static void timesync_onchannelcallback(void *context);
64 static struct hv_util_service util_timesynch = {
65 	.util_cb = timesync_onchannelcallback,
66 };
67 
68 static void heartbeat_onchannelcallback(void *context);
69 static struct hv_util_service util_heartbeat = {
70 	.util_cb = heartbeat_onchannelcallback,
71 };
72 
73 static struct hv_util_service util_kvp = {
74 	.util_cb = hv_kvp_onchannelcallback,
75 	.util_init = hv_kvp_init,
76 	.util_deinit = hv_kvp_deinit,
77 };
78 
79 static struct hv_util_service util_vss = {
80 	.util_cb = hv_vss_onchannelcallback,
81 	.util_init = hv_vss_init,
82 	.util_deinit = hv_vss_deinit,
83 };
84 
85 static void perform_shutdown(struct work_struct *dummy)
86 {
87 	orderly_poweroff(true);
88 }
89 
90 /*
91  * Perform the shutdown operation in a thread context.
92  */
93 static DECLARE_WORK(shutdown_work, perform_shutdown);
94 
95 static void shutdown_onchannelcallback(void *context)
96 {
97 	struct vmbus_channel *channel = context;
98 	u32 recvlen;
99 	u64 requestid;
100 	bool execute_shutdown = false;
101 	u8  *shut_txf_buf = util_shutdown.recv_buffer;
102 
103 	struct shutdown_msg_data *shutdown_msg;
104 
105 	struct icmsg_hdr *icmsghdrp;
106 	struct icmsg_negotiate *negop = NULL;
107 
108 	vmbus_recvpacket(channel, shut_txf_buf,
109 			 PAGE_SIZE, &recvlen, &requestid);
110 
111 	if (recvlen > 0) {
112 		icmsghdrp = (struct icmsg_hdr *)&shut_txf_buf[
113 			sizeof(struct vmbuspipe_hdr)];
114 
115 		if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) {
116 			vmbus_prep_negotiate_resp(icmsghdrp, negop,
117 					shut_txf_buf, util_fw_version,
118 					sd_srv_version);
119 		} else {
120 			shutdown_msg =
121 				(struct shutdown_msg_data *)&shut_txf_buf[
122 					sizeof(struct vmbuspipe_hdr) +
123 					sizeof(struct icmsg_hdr)];
124 
125 			switch (shutdown_msg->flags) {
126 			case 0:
127 			case 1:
128 				icmsghdrp->status = HV_S_OK;
129 				execute_shutdown = true;
130 
131 				pr_info("Shutdown request received -"
132 					    " graceful shutdown initiated\n");
133 				break;
134 			default:
135 				icmsghdrp->status = HV_E_FAIL;
136 				execute_shutdown = false;
137 
138 				pr_info("Shutdown request received -"
139 					    " Invalid request\n");
140 				break;
141 			}
142 		}
143 
144 		icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION
145 			| ICMSGHDRFLAG_RESPONSE;
146 
147 		vmbus_sendpacket(channel, shut_txf_buf,
148 				       recvlen, requestid,
149 				       VM_PKT_DATA_INBAND, 0);
150 	}
151 
152 	if (execute_shutdown == true)
153 		schedule_work(&shutdown_work);
154 }
155 
156 /*
157  * Set guest time to host UTC time.
158  */
159 static inline void do_adj_guesttime(u64 hosttime)
160 {
161 	s64 host_tns;
162 	struct timespec host_ts;
163 
164 	host_tns = (hosttime - WLTIMEDELTA) * 100;
165 	host_ts = ns_to_timespec(host_tns);
166 
167 	do_settimeofday(&host_ts);
168 }
169 
170 /*
171  * Set the host time in a process context.
172  */
173 
174 struct adj_time_work {
175 	struct work_struct work;
176 	u64	host_time;
177 };
178 
179 static void hv_set_host_time(struct work_struct *work)
180 {
181 	struct adj_time_work	*wrk;
182 
183 	wrk = container_of(work, struct adj_time_work, work);
184 	do_adj_guesttime(wrk->host_time);
185 	kfree(wrk);
186 }
187 
188 /*
189  * Synchronize time with host after reboot, restore, etc.
190  *
191  * ICTIMESYNCFLAG_SYNC flag bit indicates reboot, restore events of the VM.
192  * After reboot the flag ICTIMESYNCFLAG_SYNC is included in the first time
193  * message after the timesync channel is opened. Since the hv_utils module is
194  * loaded after hv_vmbus, the first message is usually missed. The other
195  * thing is, systime is automatically set to emulated hardware clock which may
196  * not be UTC time or in the same time zone. So, to override these effects, we
197  * use the first 50 time samples for initial system time setting.
198  */
199 static inline void adj_guesttime(u64 hosttime, u8 flags)
200 {
201 	struct adj_time_work    *wrk;
202 	static s32 scnt = 50;
203 
204 	wrk = kmalloc(sizeof(struct adj_time_work), GFP_ATOMIC);
205 	if (wrk == NULL)
206 		return;
207 
208 	wrk->host_time = hosttime;
209 	if ((flags & ICTIMESYNCFLAG_SYNC) != 0) {
210 		INIT_WORK(&wrk->work, hv_set_host_time);
211 		schedule_work(&wrk->work);
212 		return;
213 	}
214 
215 	if ((flags & ICTIMESYNCFLAG_SAMPLE) != 0 && scnt > 0) {
216 		scnt--;
217 		INIT_WORK(&wrk->work, hv_set_host_time);
218 		schedule_work(&wrk->work);
219 	} else
220 		kfree(wrk);
221 }
222 
223 /*
224  * Time Sync Channel message handler.
225  */
226 static void timesync_onchannelcallback(void *context)
227 {
228 	struct vmbus_channel *channel = context;
229 	u32 recvlen;
230 	u64 requestid;
231 	struct icmsg_hdr *icmsghdrp;
232 	struct ictimesync_data *timedatap;
233 	u8 *time_txf_buf = util_timesynch.recv_buffer;
234 	struct icmsg_negotiate *negop = NULL;
235 
236 	vmbus_recvpacket(channel, time_txf_buf,
237 			 PAGE_SIZE, &recvlen, &requestid);
238 
239 	if (recvlen > 0) {
240 		icmsghdrp = (struct icmsg_hdr *)&time_txf_buf[
241 				sizeof(struct vmbuspipe_hdr)];
242 
243 		if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) {
244 			vmbus_prep_negotiate_resp(icmsghdrp, negop,
245 						time_txf_buf,
246 						util_fw_version,
247 						ts_srv_version);
248 		} else {
249 			timedatap = (struct ictimesync_data *)&time_txf_buf[
250 				sizeof(struct vmbuspipe_hdr) +
251 				sizeof(struct icmsg_hdr)];
252 			adj_guesttime(timedatap->parenttime, timedatap->flags);
253 		}
254 
255 		icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION
256 			| ICMSGHDRFLAG_RESPONSE;
257 
258 		vmbus_sendpacket(channel, time_txf_buf,
259 				recvlen, requestid,
260 				VM_PKT_DATA_INBAND, 0);
261 	}
262 }
263 
264 /*
265  * Heartbeat functionality.
266  * Every two seconds, Hyper-V send us a heartbeat request message.
267  * we respond to this message, and Hyper-V knows we are alive.
268  */
269 static void heartbeat_onchannelcallback(void *context)
270 {
271 	struct vmbus_channel *channel = context;
272 	u32 recvlen;
273 	u64 requestid;
274 	struct icmsg_hdr *icmsghdrp;
275 	struct heartbeat_msg_data *heartbeat_msg;
276 	u8 *hbeat_txf_buf = util_heartbeat.recv_buffer;
277 	struct icmsg_negotiate *negop = NULL;
278 
279 	vmbus_recvpacket(channel, hbeat_txf_buf,
280 			 PAGE_SIZE, &recvlen, &requestid);
281 
282 	if (recvlen > 0) {
283 		icmsghdrp = (struct icmsg_hdr *)&hbeat_txf_buf[
284 				sizeof(struct vmbuspipe_hdr)];
285 
286 		if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) {
287 			vmbus_prep_negotiate_resp(icmsghdrp, negop,
288 				hbeat_txf_buf, util_fw_version,
289 				hb_srv_version);
290 		} else {
291 			heartbeat_msg =
292 				(struct heartbeat_msg_data *)&hbeat_txf_buf[
293 					sizeof(struct vmbuspipe_hdr) +
294 					sizeof(struct icmsg_hdr)];
295 
296 			heartbeat_msg->seq_num += 1;
297 		}
298 
299 		icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION
300 			| ICMSGHDRFLAG_RESPONSE;
301 
302 		vmbus_sendpacket(channel, hbeat_txf_buf,
303 				       recvlen, requestid,
304 				       VM_PKT_DATA_INBAND, 0);
305 	}
306 }
307 
308 static int util_probe(struct hv_device *dev,
309 			const struct hv_vmbus_device_id *dev_id)
310 {
311 	struct hv_util_service *srv =
312 		(struct hv_util_service *)dev_id->driver_data;
313 	int ret;
314 
315 	srv->recv_buffer = kmalloc(PAGE_SIZE * 2, GFP_KERNEL);
316 	if (!srv->recv_buffer)
317 		return -ENOMEM;
318 	if (srv->util_init) {
319 		ret = srv->util_init(srv);
320 		if (ret) {
321 			ret = -ENODEV;
322 			goto error1;
323 		}
324 	}
325 
326 	/*
327 	 * The set of services managed by the util driver are not performance
328 	 * critical and do not need batched reading. Furthermore, some services
329 	 * such as KVP can only handle one message from the host at a time.
330 	 * Turn off batched reading for all util drivers before we open the
331 	 * channel.
332 	 */
333 
334 	set_channel_read_state(dev->channel, false);
335 
336 	ret = vmbus_open(dev->channel, 4 * PAGE_SIZE, 4 * PAGE_SIZE, NULL, 0,
337 			srv->util_cb, dev->channel);
338 	if (ret)
339 		goto error;
340 
341 	hv_set_drvdata(dev, srv);
342 	/*
343 	 * Based on the host; initialize the framework and
344 	 * service version numbers we will negotiate.
345 	 */
346 	switch (vmbus_proto_version) {
347 	case (VERSION_WS2008):
348 		util_fw_version = UTIL_WS2K8_FW_VERSION;
349 		sd_srv_version = SD_WS2008_VERSION;
350 		ts_srv_version = TS_WS2008_VERSION;
351 		hb_srv_version = HB_WS2008_VERSION;
352 		break;
353 
354 	default:
355 		util_fw_version = UTIL_FW_VERSION;
356 		sd_srv_version = SD_VERSION;
357 		ts_srv_version = TS_VERSION;
358 		hb_srv_version = HB_VERSION;
359 	}
360 
361 	return 0;
362 
363 error:
364 	if (srv->util_deinit)
365 		srv->util_deinit();
366 error1:
367 	kfree(srv->recv_buffer);
368 	return ret;
369 }
370 
371 static int util_remove(struct hv_device *dev)
372 {
373 	struct hv_util_service *srv = hv_get_drvdata(dev);
374 
375 	vmbus_close(dev->channel);
376 	if (srv->util_deinit)
377 		srv->util_deinit();
378 	kfree(srv->recv_buffer);
379 
380 	return 0;
381 }
382 
383 static const struct hv_vmbus_device_id id_table[] = {
384 	/* Shutdown guid */
385 	{ HV_SHUTDOWN_GUID,
386 	  .driver_data = (unsigned long)&util_shutdown
387 	},
388 	/* Time synch guid */
389 	{ HV_TS_GUID,
390 	  .driver_data = (unsigned long)&util_timesynch
391 	},
392 	/* Heartbeat guid */
393 	{ HV_HEART_BEAT_GUID,
394 	  .driver_data = (unsigned long)&util_heartbeat
395 	},
396 	/* KVP guid */
397 	{ HV_KVP_GUID,
398 	  .driver_data = (unsigned long)&util_kvp
399 	},
400 	/* VSS GUID */
401 	{ HV_VSS_GUID,
402 	  .driver_data = (unsigned long)&util_vss
403 	},
404 	{ },
405 };
406 
407 MODULE_DEVICE_TABLE(vmbus, id_table);
408 
409 /* The one and only one */
410 static  struct hv_driver util_drv = {
411 	.name = "hv_util",
412 	.id_table = id_table,
413 	.probe =  util_probe,
414 	.remove =  util_remove,
415 };
416 
417 static int __init init_hyperv_utils(void)
418 {
419 	pr_info("Registering HyperV Utility Driver\n");
420 
421 	return vmbus_driver_register(&util_drv);
422 }
423 
424 static void exit_hyperv_utils(void)
425 {
426 	pr_info("De-Registered HyperV Utility Driver\n");
427 
428 	vmbus_driver_unregister(&util_drv);
429 }
430 
431 module_init(init_hyperv_utils);
432 module_exit(exit_hyperv_utils);
433 
434 MODULE_DESCRIPTION("Hyper-V Utilities");
435 MODULE_LICENSE("GPL");
436