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 static void shutdown_onchannelcallback(void *context);
  32 static struct hv_util_service util_shutdown = {
  33         .util_cb = shutdown_onchannelcallback,
  34 };
  35
  36 static void timesync_onchannelcallback(void *context);
  37 static struct hv_util_service util_timesynch = {
  38         .util_cb = timesync_onchannelcallback,
  39 };
  40
  41 static void heartbeat_onchannelcallback(void *context);
  42 static struct hv_util_service util_heartbeat = {
  43         .util_cb = heartbeat_onchannelcallback,
  44 };
  45
  46 static struct hv_util_service util_kvp = {
  47         .util_cb = hv_kvp_onchannelcallback,
  48         .util_init = hv_kvp_init,
  49         .util_deinit = hv_kvp_deinit,
  50 };
  51
  52 static void shutdown_onchannelcallback(void *context)
  53 {
  54         struct vmbus_channel *channel = context;
  55         u32 recvlen;
  56         u64 requestid;
  57         u8  execute_shutdown = false;
  58         u8  *shut_txf_buf = util_shutdown.recv_buffer;
  59
  60         struct shutdown_msg_data *shutdown_msg;
  61
  62         struct icmsg_hdr *icmsghdrp;
  63         struct icmsg_negotiate *negop = NULL;
  64
  65         vmbus_recvpacket(channel, shut_txf_buf,
  66                          PAGE_SIZE, &recvlen, &requestid);
  67
  68         if (recvlen > 0) {
  69                 icmsghdrp = (struct icmsg_hdr *)&shut_txf_buf[
  70                         sizeof(struct vmbuspipe_hdr)];
  71
  72                 if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) {
  73                         vmbus_prep_negotiate_resp(icmsghdrp, negop, shut_txf_buf);
  74                 } else {
  75                         shutdown_msg =
  76                                 (struct shutdown_msg_data *)&shut_txf_buf[
  77                                         sizeof(struct vmbuspipe_hdr) +
  78                                         sizeof(struct icmsg_hdr)];
  79
  80                         switch (shutdown_msg->flags) {
  81                         case 0:
  82                         case 1:
  83                                 icmsghdrp->status = HV_S_OK;
  84                                 execute_shutdown = true;
  85
  86                                 pr_info("Shutdown request received -"
  87                                             " graceful shutdown initiated\n");
  88                                 break;
  89                         default:
  90                                 icmsghdrp->status = HV_E_FAIL;
  91                                 execute_shutdown = false;
  92
  93                                 pr_info("Shutdown request received -"
  94                                             " Invalid request\n");
  95                                 break;
  96                         }
  97                 }
  98
  99                 icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION
 100                         | ICMSGHDRFLAG_RESPONSE;
 101
 102                 vmbus_sendpacket(channel, shut_txf_buf,
 103                                        recvlen, requestid,
 104                                        VM_PKT_DATA_INBAND, 0);
 105         }
 106
 107         if (execute_shutdown == true)
 108                 orderly_poweroff(true);
 109 }
 110
 111 /*
 112  * Set guest time to host UTC time.
 113  */
 114 static inline void do_adj_guesttime(u64 hosttime)
 115 {
 116         s64 host_tns;
 117         struct timespec host_ts;
 118
 119         host_tns = (hosttime - WLTIMEDELTA) * 100;
 120         host_ts = ns_to_timespec(host_tns);
 121
 122         do_settimeofday(&host_ts);
 123 }
 124
 125 /*
 126  * Set the host time in a process context.
 127  */
 128
 129 struct adj_time_work {
 130         struct work_struct work;
 131         u64     host_time;
 132 };
 133
 134 static void hv_set_host_time(struct work_struct *work)
 135 {
 136         struct adj_time_work    *wrk;
 137
 138         wrk = container_of(work, struct adj_time_work, work);
 139         do_adj_guesttime(wrk->host_time);
 140         kfree(wrk);
 141 }
 142
 143 /*
 144  * Synchronize time with host after reboot, restore, etc.
 145  *
 146  * ICTIMESYNCFLAG_SYNC flag bit indicates reboot, restore events of the VM.
 147  * After reboot the flag ICTIMESYNCFLAG_SYNC is included in the first time
 148  * message after the timesync channel is opened. Since the hv_utils module is
 149  * loaded after hv_vmbus, the first message is usually missed. The other
 150  * thing is, systime is automatically set to emulated hardware clock which may
 151  * not be UTC time or in the same time zone. So, to override these effects, we
 152  * use the first 50 time samples for initial system time setting.
 153  */
 154 static inline void adj_guesttime(u64 hosttime, u8 flags)
 155 {
 156         struct adj_time_work    *wrk;
 157         static s32 scnt = 50;
 158
 159         wrk = kmalloc(sizeof(struct adj_time_work), GFP_ATOMIC);
 160         if (wrk == NULL)
 161                 return;
 162
 163         wrk->host_time = hosttime;
 164         if ((flags & ICTIMESYNCFLAG_SYNC) != 0) {
 165                 INIT_WORK(&wrk->work, hv_set_host_time);
 166                 schedule_work(&wrk->work);
 167                 return;
 168         }
 169
 170         if ((flags & ICTIMESYNCFLAG_SAMPLE) != 0 && scnt > 0) {
 171                 scnt--;
 172                 INIT_WORK(&wrk->work, hv_set_host_time);
 173                 schedule_work(&wrk->work);
 174         } else
 175                 kfree(wrk);
 176 }
 177
 178 /*
 179  * Time Sync Channel message handler.
 180  */
 181 static void timesync_onchannelcallback(void *context)
 182 {
 183         struct vmbus_channel *channel = context;
 184         u32 recvlen;
 185         u64 requestid;
 186         struct icmsg_hdr *icmsghdrp;
 187         struct ictimesync_data *timedatap;
 188         u8 *time_txf_buf = util_timesynch.recv_buffer;
 189
 190         vmbus_recvpacket(channel, time_txf_buf,
 191                          PAGE_SIZE, &recvlen, &requestid);
 192
 193         if (recvlen > 0) {
 194                 icmsghdrp = (struct icmsg_hdr *)&time_txf_buf[
 195                                 sizeof(struct vmbuspipe_hdr)];
 196
 197                 if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) {
 198                         vmbus_prep_negotiate_resp(icmsghdrp, NULL, time_txf_buf);
 199                 } else {
 200                         timedatap = (struct ictimesync_data *)&time_txf_buf[
 201                                 sizeof(struct vmbuspipe_hdr) +
 202                                 sizeof(struct icmsg_hdr)];
 203                         adj_guesttime(timedatap->parenttime, timedatap->flags);
 204                 }
 205
 206                 icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION
 207                         | ICMSGHDRFLAG_RESPONSE;
 208
 209                 vmbus_sendpacket(channel, time_txf_buf,
 210                                 recvlen, requestid,
 211                                 VM_PKT_DATA_INBAND, 0);
 212         }
 213 }
 214
 215 /*
 216  * Heartbeat functionality.
 217  * Every two seconds, Hyper-V send us a heartbeat request message.
 218  * we respond to this message, and Hyper-V knows we are alive.
 219  */
 220 static void heartbeat_onchannelcallback(void *context)
 221 {
 222         struct vmbus_channel *channel = context;
 223         u32 recvlen;
 224         u64 requestid;
 225         struct icmsg_hdr *icmsghdrp;
 226         struct heartbeat_msg_data *heartbeat_msg;
 227         u8 *hbeat_txf_buf = util_heartbeat.recv_buffer;
 228
 229         vmbus_recvpacket(channel, hbeat_txf_buf,
 230                          PAGE_SIZE, &recvlen, &requestid);
 231
 232         if (recvlen > 0) {
 233                 icmsghdrp = (struct icmsg_hdr *)&hbeat_txf_buf[
 234                                 sizeof(struct vmbuspipe_hdr)];
 235
 236                 if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) {
 237                         vmbus_prep_negotiate_resp(icmsghdrp, NULL, hbeat_txf_buf);
 238                 } else {
 239                         heartbeat_msg =
 240                                 (struct heartbeat_msg_data *)&hbeat_txf_buf[
 241                                         sizeof(struct vmbuspipe_hdr) +
 242                                         sizeof(struct icmsg_hdr)];
 243
 244                         heartbeat_msg->seq_num += 1;
 245                 }
 246
 247                 icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION
 248                         | ICMSGHDRFLAG_RESPONSE;
 249
 250                 vmbus_sendpacket(channel, hbeat_txf_buf,
 251                                        recvlen, requestid,
 252                                        VM_PKT_DATA_INBAND, 0);
 253         }
 254 }
 255
 256 static int util_probe(struct hv_device *dev,
 257                         const struct hv_vmbus_device_id *dev_id)
 258 {
 259         struct hv_util_service *srv =
 260                 (struct hv_util_service *)dev_id->driver_data;
 261         int ret;
 262
 263         srv->recv_buffer = kmalloc(PAGE_SIZE, GFP_KERNEL);
 264         if (!srv->recv_buffer)
 265                 return -ENOMEM;
 266         if (srv->util_init) {
 267                 ret = srv->util_init(srv);
 268                 if (ret) {
 269                         ret = -ENODEV;
 270                         goto error1;
 271                 }
 272         }
 273
 274         ret = vmbus_open(dev->channel, 2 * PAGE_SIZE, 2 * PAGE_SIZE, NULL, 0,
 275                         srv->util_cb, dev->channel);
 276         if (ret)
 277                 goto error;
 278
 279         hv_set_drvdata(dev, srv);
 280         return 0;
 281
 282 error:
 283         if (srv->util_deinit)
 284                 srv->util_deinit();
 285 error1:
 286         kfree(srv->recv_buffer);
 287         return ret;
 288 }
 289
 290 static int util_remove(struct hv_device *dev)
 291 {
 292         struct hv_util_service *srv = hv_get_drvdata(dev);
 293
 294         vmbus_close(dev->channel);
 295         if (srv->util_deinit)
 296                 srv->util_deinit();
 297         kfree(srv->recv_buffer);
 298
 299         return 0;
 300 }
 301
 302 static const struct hv_vmbus_device_id id_table[] = {
 303         /* Shutdown guid */
 304         { VMBUS_DEVICE(0x31, 0x60, 0x0B, 0X0E, 0x13, 0x52, 0x34, 0x49,
 305                        0x81, 0x8B, 0x38, 0XD9, 0x0C, 0xED, 0x39, 0xDB)
 306           .driver_data = (unsigned long)&util_shutdown },
 307         /* Time synch guid */
 308         { VMBUS_DEVICE(0x30, 0xe6, 0x27, 0x95, 0xae, 0xd0, 0x7b, 0x49,
 309                        0xad, 0xce, 0xe8, 0x0a, 0xb0, 0x17, 0x5c, 0xaf)
 310           .driver_data = (unsigned long)&util_timesynch },
 311         /* Heartbeat guid */
 312         { VMBUS_DEVICE(0x39, 0x4f, 0x16, 0x57, 0x15, 0x91, 0x78, 0x4e,
 313                        0xab, 0x55, 0x38, 0x2f, 0x3b, 0xd5, 0x42, 0x2d)
 314           .driver_data = (unsigned long)&util_heartbeat },
 315         /* KVP guid */
 316         { VMBUS_DEVICE(0xe7, 0xf4, 0xa0, 0xa9, 0x45, 0x5a, 0x96, 0x4d,
 317                        0xb8, 0x27, 0x8a, 0x84, 0x1e, 0x8c, 0x3,  0xe6)
 318           .driver_data = (unsigned long)&util_kvp },
 319         { },
 320 };
 321
 322 MODULE_DEVICE_TABLE(vmbus, id_table);
 323
 324 /* The one and only one */
 325 static  struct hv_driver util_drv = {
 326         .name = "hv_util",
 327         .id_table = id_table,
 328         .probe =  util_probe,
 329         .remove =  util_remove,
 330 };
 331
 332 static int __init init_hyperv_utils(void)
 333 {
 334         pr_info("Registering HyperV Utility Driver\n");
 335
 336         return vmbus_driver_register(&util_drv);
 337 }
 338
 339 static void exit_hyperv_utils(void)
 340 {
 341         pr_info("De-Registered HyperV Utility Driver\n");
 342
 343         vmbus_driver_unregister(&util_drv);
 344 }
 345
 346 module_init(init_hyperv_utils);
 347 module_exit(exit_hyperv_utils);
 348
 349 MODULE_DESCRIPTION("Hyper-V Utilities");
 350 MODULE_VERSION(HV_DRV_VERSION);
 351 MODULE_LICENSE("GPL");