drivers/staging/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
  30 #include "hyperv.h"
  31 #include "hv_kvp.h"
  32
  33 static u8 *shut_txf_buf;
  34 static u8 *time_txf_buf;
  35 static u8 *hbeat_txf_buf;
  36
  37 static void shutdown_onchannelcallback(void *context)
  38 {
  39         struct vmbus_channel *channel = context;
  40         u32 recvlen;
  41         u64 requestid;
  42         u8  execute_shutdown = false;
  43
  44         struct shutdown_msg_data *shutdown_msg;
  45
  46         struct icmsg_hdr *icmsghdrp;
  47         struct icmsg_negotiate *negop = NULL;
  48
  49         vmbus_recvpacket(channel, shut_txf_buf,
  50                          PAGE_SIZE, &recvlen, &requestid);
  51
  52         if (recvlen > 0) {
  53                 icmsghdrp = (struct icmsg_hdr *)&shut_txf_buf[
  54                         sizeof(struct vmbuspipe_hdr)];
  55
  56                 if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) {
  57                         prep_negotiate_resp(icmsghdrp, negop, shut_txf_buf);
  58                 } else {
  59                         shutdown_msg =
  60                                 (struct shutdown_msg_data *)&shut_txf_buf[
  61                                         sizeof(struct vmbuspipe_hdr) +
  62                                         sizeof(struct icmsg_hdr)];
  63
  64                         switch (shutdown_msg->flags) {
  65                         case 0:
  66                         case 1:
  67                                 icmsghdrp->status = HV_S_OK;
  68                                 execute_shutdown = true;
  69
  70                                 pr_info("Shutdown request received -"
  71                                             " graceful shutdown initiated\n");
  72                                 break;
  73                         default:
  74                                 icmsghdrp->status = HV_E_FAIL;
  75                                 execute_shutdown = false;
  76
  77                                 pr_info("Shutdown request received -"
  78                                             " Invalid request\n");
  79                                 break;
  80                         }
  81                 }
  82
  83                 icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION
  84                         | ICMSGHDRFLAG_RESPONSE;
  85
  86                 vmbus_sendpacket(channel, shut_txf_buf,
  87                                        recvlen, requestid,
  88                                        VM_PKT_DATA_INBAND, 0);
  89         }
  90
  91         if (execute_shutdown == true)
  92                 orderly_poweroff(true);
  93 }
  94
  95 /*
  96  * Set guest time to host UTC time.
  97  */
  98 static inline void do_adj_guesttime(u64 hosttime)
  99 {
 100         s64 host_tns;
 101         struct timespec host_ts;
 102
 103         host_tns = (hosttime - WLTIMEDELTA) * 100;
 104         host_ts = ns_to_timespec(host_tns);
 105
 106         do_settimeofday(&host_ts);
 107 }
 108
 109 /*
 110  * Set the host time in a process context.
 111  */
 112
 113 struct adj_time_work {
 114         struct work_struct work;
 115         u64     host_time;
 116 };
 117
 118 static void hv_set_host_time(struct work_struct *work)
 119 {
 120         struct adj_time_work    *wrk;
 121
 122         wrk = container_of(work, struct adj_time_work, work);
 123         do_adj_guesttime(wrk->host_time);
 124         kfree(wrk);
 125 }
 126
 127 /*
 128  * Synchronize time with host after reboot, restore, etc.
 129  *
 130  * ICTIMESYNCFLAG_SYNC flag bit indicates reboot, restore events of the VM.
 131  * After reboot the flag ICTIMESYNCFLAG_SYNC is included in the first time
 132  * message after the timesync channel is opened. Since the hv_utils module is
 133  * loaded after hv_vmbus, the first message is usually missed. The other
 134  * thing is, systime is automatically set to emulated hardware clock which may
 135  * not be UTC time or in the same time zone. So, to override these effects, we
 136  * use the first 50 time samples for initial system time setting.
 137  */
 138 static inline void adj_guesttime(u64 hosttime, u8 flags)
 139 {
 140         struct adj_time_work    *wrk;
 141         static s32 scnt = 50;
 142
 143         wrk = kmalloc(sizeof(struct adj_time_work), GFP_ATOMIC);
 144         if (wrk == NULL)
 145                 return;
 146
 147         wrk->host_time = hosttime;
 148         if ((flags & ICTIMESYNCFLAG_SYNC) != 0) {
 149                 INIT_WORK(&wrk->work, hv_set_host_time);
 150                 schedule_work(&wrk->work);
 151                 return;
 152         }
 153
 154         if ((flags & ICTIMESYNCFLAG_SAMPLE) != 0 && scnt > 0) {
 155                 scnt--;
 156                 INIT_WORK(&wrk->work, hv_set_host_time);
 157                 schedule_work(&wrk->work);
 158         } else
 159                 kfree(wrk);
 160 }
 161
 162 /*
 163  * Time Sync Channel message handler.
 164  */
 165 static void timesync_onchannelcallback(void *context)
 166 {
 167         struct vmbus_channel *channel = context;
 168         u32 recvlen;
 169         u64 requestid;
 170         struct icmsg_hdr *icmsghdrp;
 171         struct ictimesync_data *timedatap;
 172
 173         vmbus_recvpacket(channel, time_txf_buf,
 174                          PAGE_SIZE, &recvlen, &requestid);
 175
 176         if (recvlen > 0) {
 177                 icmsghdrp = (struct icmsg_hdr *)&time_txf_buf[
 178                                 sizeof(struct vmbuspipe_hdr)];
 179
 180                 if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) {
 181                         prep_negotiate_resp(icmsghdrp, NULL, time_txf_buf);
 182                 } else {
 183                         timedatap = (struct ictimesync_data *)&time_txf_buf[
 184                                 sizeof(struct vmbuspipe_hdr) +
 185                                 sizeof(struct icmsg_hdr)];
 186                         adj_guesttime(timedatap->parenttime, timedatap->flags);
 187                 }
 188
 189                 icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION
 190                         | ICMSGHDRFLAG_RESPONSE;
 191
 192                 vmbus_sendpacket(channel, time_txf_buf,
 193                                 recvlen, requestid,
 194                                 VM_PKT_DATA_INBAND, 0);
 195         }
 196 }
 197
 198 /*
 199  * Heartbeat functionality.
 200  * Every two seconds, Hyper-V send us a heartbeat request message.
 201  * we respond to this message, and Hyper-V knows we are alive.
 202  */
 203 static void heartbeat_onchannelcallback(void *context)
 204 {
 205         struct vmbus_channel *channel = context;
 206         u32 recvlen;
 207         u64 requestid;
 208         struct icmsg_hdr *icmsghdrp;
 209         struct heartbeat_msg_data *heartbeat_msg;
 210
 211         vmbus_recvpacket(channel, hbeat_txf_buf,
 212                          PAGE_SIZE, &recvlen, &requestid);
 213
 214         if (recvlen > 0) {
 215                 icmsghdrp = (struct icmsg_hdr *)&hbeat_txf_buf[
 216                                 sizeof(struct vmbuspipe_hdr)];
 217
 218                 if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) {
 219                         prep_negotiate_resp(icmsghdrp, NULL, hbeat_txf_buf);
 220                 } else {
 221                         heartbeat_msg =
 222                                 (struct heartbeat_msg_data *)&hbeat_txf_buf[
 223                                         sizeof(struct vmbuspipe_hdr) +
 224                                         sizeof(struct icmsg_hdr)];
 225
 226                         heartbeat_msg->seq_num += 1;
 227                 }
 228
 229                 icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION
 230                         | ICMSGHDRFLAG_RESPONSE;
 231
 232                 vmbus_sendpacket(channel, hbeat_txf_buf,
 233                                        recvlen, requestid,
 234                                        VM_PKT_DATA_INBAND, 0);
 235         }
 236 }
 237
 238 /*
 239  * The devices managed by the util driver don't need any additional
 240  * setup.
 241  */
 242 static int util_probe(struct hv_device *dev)
 243 {
 244         return 0;
 245 }
 246
 247 static int util_remove(struct hv_device *dev)
 248 {
 249         return 0;
 250 }
 251
 252 static const struct hv_vmbus_device_id id_table[] = {
 253         /* Shutdown guid */
 254         { VMBUS_DEVICE(0x31, 0x60, 0x0B, 0X0E, 0x13, 0x52, 0x34, 0x49,
 255                        0x81, 0x8B, 0x38, 0XD9, 0x0C, 0xED, 0x39, 0xDB) },
 256         /* Time synch guid */
 257         { VMBUS_DEVICE(0x30, 0xe6, 0x27, 0x95, 0xae, 0xd0, 0x7b, 0x49,
 258                        0xad, 0xce, 0xe8, 0x0a, 0xb0, 0x17, 0x5c, 0xaf) },
 259         /* Heartbeat guid */
 260         { VMBUS_DEVICE(0x39, 0x4f, 0x16, 0x57, 0x15, 0x91, 0x78, 0x4e,
 261                        0xab, 0x55, 0x38, 0x2f, 0x3b, 0xd5, 0x42, 0x2d) },
 262         /* KVP guid */
 263         { VMBUS_DEVICE(0xe7, 0xf4, 0xa0, 0xa9, 0x45, 0x5a, 0x96, 0x4d,
 264                        0xb8, 0x27, 0x8a, 0x84, 0x1e, 0x8c, 0x3,  0xe6) },
 265         { },
 266 };
 267
 268 MODULE_DEVICE_TABLE(vmbus, id_table);
 269
 270 /* The one and only one */
 271 static  struct hv_driver util_drv = {
 272         .name = "hv_util",
 273         .id_table = id_table,
 274         .probe =  util_probe,
 275         .remove =  util_remove,
 276 };
 277
 278 static int __init init_hyperv_utils(void)
 279 {
 280         pr_info("Registering HyperV Utility Driver\n");
 281
 282         if (hv_kvp_init())
 283                 return -ENODEV;
 284
 285
 286         shut_txf_buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
 287         time_txf_buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
 288         hbeat_txf_buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
 289
 290         if (!shut_txf_buf || !time_txf_buf || !hbeat_txf_buf) {
 291                 pr_info("Unable to allocate memory for receive buffer\n");
 292                 kfree(shut_txf_buf);
 293                 kfree(time_txf_buf);
 294                 kfree(hbeat_txf_buf);
 295                 return -ENOMEM;
 296         }
 297
 298         hv_cb_utils[HV_SHUTDOWN_MSG].callback = &shutdown_onchannelcallback;
 299
 300         hv_cb_utils[HV_TIMESYNC_MSG].callback = &timesync_onchannelcallback;
 301
 302         hv_cb_utils[HV_HEARTBEAT_MSG].callback = &heartbeat_onchannelcallback;
 303
 304         hv_cb_utils[HV_KVP_MSG].callback = &hv_kvp_onchannelcallback;
 305
 306         return vmbus_driver_register(&util_drv);
 307 }
 308
 309 static void exit_hyperv_utils(void)
 310 {
 311         pr_info("De-Registered HyperV Utility Driver\n");
 312
 313         if (hv_cb_utils[HV_SHUTDOWN_MSG].channel != NULL)
 314                 hv_cb_utils[HV_SHUTDOWN_MSG].channel->onchannel_callback =
 315                         &chn_cb_negotiate;
 316         hv_cb_utils[HV_SHUTDOWN_MSG].callback = NULL;
 317
 318         if (hv_cb_utils[HV_TIMESYNC_MSG].channel != NULL)
 319                 hv_cb_utils[HV_TIMESYNC_MSG].channel->onchannel_callback =
 320                         &chn_cb_negotiate;
 321         hv_cb_utils[HV_TIMESYNC_MSG].callback = NULL;
 322
 323         if (hv_cb_utils[HV_HEARTBEAT_MSG].channel != NULL)
 324                 hv_cb_utils[HV_HEARTBEAT_MSG].channel->onchannel_callback =
 325                         &chn_cb_negotiate;
 326         hv_cb_utils[HV_HEARTBEAT_MSG].callback = NULL;
 327
 328         if (hv_cb_utils[HV_KVP_MSG].channel != NULL)
 329                 hv_cb_utils[HV_KVP_MSG].channel->onchannel_callback =
 330                         &chn_cb_negotiate;
 331         hv_cb_utils[HV_KVP_MSG].callback = NULL;
 332
 333         hv_kvp_deinit();
 334
 335         kfree(shut_txf_buf);
 336         kfree(time_txf_buf);
 337         kfree(hbeat_txf_buf);
 338         vmbus_driver_unregister(&util_drv);
 339 }
 340
 341 module_init(init_hyperv_utils);
 342 module_exit(exit_hyperv_utils);
 343
 344 MODULE_DESCRIPTION("Hyper-V Utilities");
 345 MODULE_VERSION(HV_DRV_VERSION);
 346 MODULE_LICENSE("GPL");