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#include "hyperv_vmbus.h"
32
33#define SD_MAJOR	3
34#define SD_MINOR	0
35#define SD_VERSION	(SD_MAJOR << 16 | SD_MINOR)
36
37#define SD_WS2008_MAJOR		1
38#define SD_WS2008_VERSION	(SD_WS2008_MAJOR << 16 | SD_MINOR)
39
40#define TS_MAJOR	3
41#define TS_MINOR	0
42#define TS_VERSION	(TS_MAJOR << 16 | TS_MINOR)
43
44#define TS_WS2008_MAJOR		1
45#define TS_WS2008_VERSION	(TS_WS2008_MAJOR << 16 | TS_MINOR)
46
47#define HB_MAJOR	3
48#define HB_MINOR 0
49#define HB_VERSION	(HB_MAJOR << 16 | HB_MINOR)
50
51#define HB_WS2008_MAJOR	1
52#define HB_WS2008_VERSION	(HB_WS2008_MAJOR << 16 | HB_MINOR)
53
54static int sd_srv_version;
55static int ts_srv_version;
56static int hb_srv_version;
57static int util_fw_version;
58
59static void shutdown_onchannelcallback(void *context);
60static struct hv_util_service util_shutdown = {
61	.util_cb = shutdown_onchannelcallback,
62};
63
64static void timesync_onchannelcallback(void *context);
65static struct hv_util_service util_timesynch = {
66	.util_cb = timesync_onchannelcallback,
67};
68
69static void heartbeat_onchannelcallback(void *context);
70static struct hv_util_service util_heartbeat = {
71	.util_cb = heartbeat_onchannelcallback,
72};
73
74static struct hv_util_service util_kvp = {
75	.util_cb = hv_kvp_onchannelcallback,
76	.util_init = hv_kvp_init,
77	.util_deinit = hv_kvp_deinit,
78};
79
80static struct hv_util_service util_vss = {
81	.util_cb = hv_vss_onchannelcallback,
82	.util_init = hv_vss_init,
83	.util_deinit = hv_vss_deinit,
84};
85
86static struct hv_util_service util_fcopy = {
87	.util_cb = hv_fcopy_onchannelcallback,
88	.util_init = hv_fcopy_init,
89	.util_deinit = hv_fcopy_deinit,
90};
91
92static void perform_shutdown(struct work_struct *dummy)
93{
94	orderly_poweroff(true);
95}
96
97/*
98 * Perform the shutdown operation in a thread context.
99 */
100static DECLARE_WORK(shutdown_work, perform_shutdown);
101
102static void shutdown_onchannelcallback(void *context)
103{
104	struct vmbus_channel *channel = context;
105	u32 recvlen;
106	u64 requestid;
107	bool execute_shutdown = false;
108	u8  *shut_txf_buf = util_shutdown.recv_buffer;
109
110	struct shutdown_msg_data *shutdown_msg;
111
112	struct icmsg_hdr *icmsghdrp;
113	struct icmsg_negotiate *negop = NULL;
114
115	vmbus_recvpacket(channel, shut_txf_buf,
116			 PAGE_SIZE, &recvlen, &requestid);
117
118	if (recvlen > 0) {
119		icmsghdrp = (struct icmsg_hdr *)&shut_txf_buf[
120			sizeof(struct vmbuspipe_hdr)];
121
122		if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) {
123			vmbus_prep_negotiate_resp(icmsghdrp, negop,
124					shut_txf_buf, util_fw_version,
125					sd_srv_version);
126		} else {
127			shutdown_msg =
128				(struct shutdown_msg_data *)&shut_txf_buf[
129					sizeof(struct vmbuspipe_hdr) +
130					sizeof(struct icmsg_hdr)];
131
132			switch (shutdown_msg->flags) {
133			case 0:
134			case 1:
135				icmsghdrp->status = HV_S_OK;
136				execute_shutdown = true;
137
138				pr_info("Shutdown request received -"
139					    " graceful shutdown initiated\n");
140				break;
141			default:
142				icmsghdrp->status = HV_E_FAIL;
143				execute_shutdown = false;
144
145				pr_info("Shutdown request received -"
146					    " Invalid request\n");
147				break;
148			}
149		}
150
151		icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION
152			| ICMSGHDRFLAG_RESPONSE;
153
154		vmbus_sendpacket(channel, shut_txf_buf,
155				       recvlen, requestid,
156				       VM_PKT_DATA_INBAND, 0);
157	}
158
159	if (execute_shutdown == true)
160		schedule_work(&shutdown_work);
161}
162
163/*
164 * Set guest time to host UTC time.
165 */
166static inline void do_adj_guesttime(u64 hosttime)
167{
168	s64 host_tns;
169	struct timespec host_ts;
170
171	host_tns = (hosttime - WLTIMEDELTA) * 100;
172	host_ts = ns_to_timespec(host_tns);
173
174	do_settimeofday(&host_ts);
175}
176
177/*
178 * Set the host time in a process context.
179 */
180
181struct adj_time_work {
182	struct work_struct work;
183	u64	host_time;
184};
185
186static void hv_set_host_time(struct work_struct *work)
187{
188	struct adj_time_work	*wrk;
189
190	wrk = container_of(work, struct adj_time_work, work);
191	do_adj_guesttime(wrk->host_time);
192	kfree(wrk);
193}
194
195/*
196 * Synchronize time with host after reboot, restore, etc.
197 *
198 * ICTIMESYNCFLAG_SYNC flag bit indicates reboot, restore events of the VM.
199 * After reboot the flag ICTIMESYNCFLAG_SYNC is included in the first time
200 * message after the timesync channel is opened. Since the hv_utils module is
201 * loaded after hv_vmbus, the first message is usually missed. The other
202 * thing is, systime is automatically set to emulated hardware clock which may
203 * not be UTC time or in the same time zone. So, to override these effects, we
204 * use the first 50 time samples for initial system time setting.
205 */
206static inline void adj_guesttime(u64 hosttime, u8 flags)
207{
208	struct adj_time_work    *wrk;
209	static s32 scnt = 50;
210
211	wrk = kmalloc(sizeof(struct adj_time_work), GFP_ATOMIC);
212	if (wrk == NULL)
213		return;
214
215	wrk->host_time = hosttime;
216	if ((flags & ICTIMESYNCFLAG_SYNC) != 0) {
217		INIT_WORK(&wrk->work, hv_set_host_time);
218		schedule_work(&wrk->work);
219		return;
220	}
221
222	if ((flags & ICTIMESYNCFLAG_SAMPLE) != 0 && scnt > 0) {
223		scnt--;
224		INIT_WORK(&wrk->work, hv_set_host_time);
225		schedule_work(&wrk->work);
226	} else
227		kfree(wrk);
228}
229
230/*
231 * Time Sync Channel message handler.
232 */
233static void timesync_onchannelcallback(void *context)
234{
235	struct vmbus_channel *channel = context;
236	u32 recvlen;
237	u64 requestid;
238	struct icmsg_hdr *icmsghdrp;
239	struct ictimesync_data *timedatap;
240	u8 *time_txf_buf = util_timesynch.recv_buffer;
241	struct icmsg_negotiate *negop = NULL;
242
243	vmbus_recvpacket(channel, time_txf_buf,
244			 PAGE_SIZE, &recvlen, &requestid);
245
246	if (recvlen > 0) {
247		icmsghdrp = (struct icmsg_hdr *)&time_txf_buf[
248				sizeof(struct vmbuspipe_hdr)];
249
250		if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) {
251			vmbus_prep_negotiate_resp(icmsghdrp, negop,
252						time_txf_buf,
253						util_fw_version,
254						ts_srv_version);
255		} else {
256			timedatap = (struct ictimesync_data *)&time_txf_buf[
257				sizeof(struct vmbuspipe_hdr) +
258				sizeof(struct icmsg_hdr)];
259			adj_guesttime(timedatap->parenttime, timedatap->flags);
260		}
261
262		icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION
263			| ICMSGHDRFLAG_RESPONSE;
264
265		vmbus_sendpacket(channel, time_txf_buf,
266				recvlen, requestid,
267				VM_PKT_DATA_INBAND, 0);
268	}
269}
270
271/*
272 * Heartbeat functionality.
273 * Every two seconds, Hyper-V send us a heartbeat request message.
274 * we respond to this message, and Hyper-V knows we are alive.
275 */
276static void heartbeat_onchannelcallback(void *context)
277{
278	struct vmbus_channel *channel = context;
279	u32 recvlen;
280	u64 requestid;
281	struct icmsg_hdr *icmsghdrp;
282	struct heartbeat_msg_data *heartbeat_msg;
283	u8 *hbeat_txf_buf = util_heartbeat.recv_buffer;
284	struct icmsg_negotiate *negop = NULL;
285
286	vmbus_recvpacket(channel, hbeat_txf_buf,
287			 PAGE_SIZE, &recvlen, &requestid);
288
289	if (recvlen > 0) {
290		icmsghdrp = (struct icmsg_hdr *)&hbeat_txf_buf[
291				sizeof(struct vmbuspipe_hdr)];
292
293		if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) {
294			vmbus_prep_negotiate_resp(icmsghdrp, negop,
295				hbeat_txf_buf, util_fw_version,
296				hb_srv_version);
297		} else {
298			heartbeat_msg =
299				(struct heartbeat_msg_data *)&hbeat_txf_buf[
300					sizeof(struct vmbuspipe_hdr) +
301					sizeof(struct icmsg_hdr)];
302
303			heartbeat_msg->seq_num += 1;
304		}
305
306		icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION
307			| ICMSGHDRFLAG_RESPONSE;
308
309		vmbus_sendpacket(channel, hbeat_txf_buf,
310				       recvlen, requestid,
311				       VM_PKT_DATA_INBAND, 0);
312	}
313}
314
315static int util_probe(struct hv_device *dev,
316			const struct hv_vmbus_device_id *dev_id)
317{
318	struct hv_util_service *srv =
319		(struct hv_util_service *)dev_id->driver_data;
320	int ret;
321
322	srv->recv_buffer = kmalloc(PAGE_SIZE * 4, GFP_KERNEL);
323	if (!srv->recv_buffer)
324		return -ENOMEM;
325	if (srv->util_init) {
326		ret = srv->util_init(srv);
327		if (ret) {
328			ret = -ENODEV;
329			goto error1;
330		}
331	}
332
333	/*
334	 * The set of services managed by the util driver are not performance
335	 * critical and do not need batched reading. Furthermore, some services
336	 * such as KVP can only handle one message from the host at a time.
337	 * Turn off batched reading for all util drivers before we open the
338	 * channel.
339	 */
340
341	set_channel_read_state(dev->channel, false);
342
343	hv_set_drvdata(dev, srv);
344
345	/*
346	 * Based on the host; initialize the framework and
347	 * service version numbers we will negotiate.
348	 */
349	switch (vmbus_proto_version) {
350	case (VERSION_WS2008):
351		util_fw_version = UTIL_WS2K8_FW_VERSION;
352		sd_srv_version = SD_WS2008_VERSION;
353		ts_srv_version = TS_WS2008_VERSION;
354		hb_srv_version = HB_WS2008_VERSION;
355		break;
356
357	default:
358		util_fw_version = UTIL_FW_VERSION;
359		sd_srv_version = SD_VERSION;
360		ts_srv_version = TS_VERSION;
361		hb_srv_version = HB_VERSION;
362	}
363
364	ret = vmbus_open(dev->channel, 4 * PAGE_SIZE, 4 * PAGE_SIZE, NULL, 0,
365			srv->util_cb, dev->channel);
366	if (ret)
367		goto error;
368
369	return 0;
370
371error:
372	if (srv->util_deinit)
373		srv->util_deinit();
374error1:
375	kfree(srv->recv_buffer);
376	return ret;
377}
378
379static int util_remove(struct hv_device *dev)
380{
381	struct hv_util_service *srv = hv_get_drvdata(dev);
382
383	if (srv->util_deinit)
384		srv->util_deinit();
385	vmbus_close(dev->channel);
386	kfree(srv->recv_buffer);
387
388	return 0;
389}
390
391static const struct hv_vmbus_device_id id_table[] = {
392	/* Shutdown guid */
393	{ HV_SHUTDOWN_GUID,
394	  .driver_data = (unsigned long)&util_shutdown
395	},
396	/* Time synch guid */
397	{ HV_TS_GUID,
398	  .driver_data = (unsigned long)&util_timesynch
399	},
400	/* Heartbeat guid */
401	{ HV_HEART_BEAT_GUID,
402	  .driver_data = (unsigned long)&util_heartbeat
403	},
404	/* KVP guid */
405	{ HV_KVP_GUID,
406	  .driver_data = (unsigned long)&util_kvp
407	},
408	/* VSS GUID */
409	{ HV_VSS_GUID,
410	  .driver_data = (unsigned long)&util_vss
411	},
412	/* File copy GUID */
413	{ HV_FCOPY_GUID,
414	  .driver_data = (unsigned long)&util_fcopy
415	},
416	{ },
417};
418
419MODULE_DEVICE_TABLE(vmbus, id_table);
420
421/* The one and only one */
422static  struct hv_driver util_drv = {
423	.name = "hv_util",
424	.id_table = id_table,
425	.probe =  util_probe,
426	.remove =  util_remove,
427};
428
429static int __init init_hyperv_utils(void)
430{
431	pr_info("Registering HyperV Utility Driver\n");
432
433	return vmbus_driver_register(&util_drv);
434}
435
436static void exit_hyperv_utils(void)
437{
438	pr_info("De-Registered HyperV Utility Driver\n");
439
440	vmbus_driver_unregister(&util_drv);
441}
442
443module_init(init_hyperv_utils);
444module_exit(exit_hyperv_utils);
445
446MODULE_DESCRIPTION("Hyper-V Utilities");
447MODULE_LICENSE("GPL");
448