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