Merge branch 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...
[platform/kernel/linux-rpi.git] / drivers / hv / hv_util.c
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
54 static int sd_srv_version;
55 static int ts_srv_version;
56 static int hb_srv_version;
57 static int util_fw_version;
58
59 static void shutdown_onchannelcallback(void *context);
60 static struct hv_util_service util_shutdown = {
61         .util_cb = shutdown_onchannelcallback,
62 };
63
64 static void timesync_onchannelcallback(void *context);
65 static struct hv_util_service util_timesynch = {
66         .util_cb = timesync_onchannelcallback,
67 };
68
69 static void heartbeat_onchannelcallback(void *context);
70 static struct hv_util_service util_heartbeat = {
71         .util_cb = heartbeat_onchannelcallback,
72 };
73
74 static 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
80 static 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
86 static 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
92 static 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  */
100 static DECLARE_WORK(shutdown_work, perform_shutdown);
101
102 static 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  */
166 static 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
181 struct adj_time_work {
182         struct work_struct work;
183         u64     host_time;
184 };
185
186 static 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  */
206 static 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  */
233 static 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  */
276 static 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
315 static 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
371 error:
372         if (srv->util_deinit)
373                 srv->util_deinit();
374 error1:
375         kfree(srv->recv_buffer);
376         return ret;
377 }
378
379 static 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
391 static 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
419 MODULE_DEVICE_TABLE(vmbus, id_table);
420
421 /* The one and only one */
422 static  struct hv_driver util_drv = {
423         .name = "hv_util",
424         .id_table = id_table,
425         .probe =  util_probe,
426         .remove =  util_remove,
427 };
428
429 static 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
436 static void exit_hyperv_utils(void)
437 {
438         pr_info("De-Registered HyperV Utility Driver\n");
439
440         vmbus_driver_unregister(&util_drv);
441 }
442
443 module_init(init_hyperv_utils);
444 module_exit(exit_hyperv_utils);
445
446 MODULE_DESCRIPTION("Hyper-V Utilities");
447 MODULE_LICENSE("GPL");