drivers/staging/hv/hv_utils.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 #include <linux/kernel.h>
  22 #include <linux/init.h>
  23 #include <linux/module.h>
  24 #include <linux/slab.h>
  25 #include <linux/sysctl.h>
  26 #include <linux/reboot.h>
  27
  28 #include "logging.h"
  29 #include "osd.h"
  30 #include "vmbus.h"
  31 #include "vmbus_packet_format.h"
  32 #include "vmbus_channel_interface.h"
  33 #include "version_info.h"
  34 #include "channel.h"
  35 #include "vmbus_private.h"
  36 #include "vmbus_api.h"
  37 #include "utils.h"
  38
  39
  40 static void shutdown_onchannelcallback(void *context)
  41 {
  42         struct vmbus_channel *channel = context;
  43         u8 *buf;
  44         u32 buflen, recvlen;
  45         u64 requestid;
  46         u8  execute_shutdown = false;
  47
  48         struct shutdown_msg_data *shutdown_msg;
  49
  50         struct icmsg_hdr *icmsghdrp;
  51         struct icmsg_negotiate *negop = NULL;
  52
  53         DPRINT_ENTER(VMBUS);
  54
  55         buflen = PAGE_SIZE;
  56         buf = kmalloc(buflen, GFP_ATOMIC);
  57
  58         VmbusChannelRecvPacket(channel, buf, buflen, &recvlen, &requestid);
  59
  60         if (recvlen > 0) {
  61                 DPRINT_DBG(VMBUS, "shutdown packet: len=%d, requestid=%lld",
  62                            recvlen, requestid);
  63
  64                 icmsghdrp = (struct icmsg_hdr *)&buf[
  65                         sizeof(struct vmbuspipe_hdr)];
  66
  67                 if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) {
  68                         prep_negotiate_resp(icmsghdrp, negop, buf);
  69                 } else {
  70                         shutdown_msg = (struct shutdown_msg_data *)&buf[
  71                                 sizeof(struct vmbuspipe_hdr) +
  72                                 sizeof(struct icmsg_hdr)];
  73
  74                         switch (shutdown_msg->flags) {
  75                         case 0:
  76                         case 1:
  77                                 icmsghdrp->status = HV_S_OK;
  78                                 execute_shutdown = true;
  79
  80                                 DPRINT_INFO(VMBUS, "Shutdown request received -"
  81                                             " gracefull shutdown initiated");
  82                                 break;
  83                         default:
  84                                 icmsghdrp->status = HV_E_FAIL;
  85                                 execute_shutdown = false;
  86
  87                                 DPRINT_INFO(VMBUS, "Shutdown request received -"
  88                                             " Invalid request");
  89                                 break;
  90                         };
  91                 }
  92
  93                 icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION
  94                         | ICMSGHDRFLAG_RESPONSE;
  95
  96                 VmbusChannelSendPacket(channel, buf,
  97                                        recvlen, requestid,
  98                                        VmbusPacketTypeDataInBand, 0);
  99         }
 100
 101         kfree(buf);
 102
 103         DPRINT_EXIT(VMBUS);
 104
 105         if (execute_shutdown == true)
 106                 orderly_poweroff(false);
 107 }
 108
 109 /*
 110  * Set guest time to host UTC time.
 111  */
 112 static inline void do_adj_guesttime(u64 hosttime)
 113 {
 114         s64 host_tns;
 115         struct timespec host_ts;
 116
 117         host_tns = (hosttime - WLTIMEDELTA) * 100;
 118         host_ts = ns_to_timespec(host_tns);
 119
 120         do_settimeofday(&host_ts);
 121 }
 122
 123 /*
 124  * Synchronize time with host after reboot, restore, etc.
 125  *
 126  * ICTIMESYNCFLAG_SYNC flag bit indicates reboot, restore events of the VM.
 127  * After reboot the flag ICTIMESYNCFLAG_SYNC is included in the first time
 128  * message after the timesync channel is opened. Since the hv_utils module is
 129  * loaded after hv_vmbus, the first message is usually missed. The other
 130  * thing is, systime is automatically set to emulated hardware clock which may
 131  * not be UTC time or in the same time zone. So, to override these effects, we
 132  * use the first 50 time samples for initial system time setting.
 133  */
 134 static inline void adj_guesttime(u64 hosttime, u8 flags)
 135 {
 136         static s32 scnt = 50;
 137
 138         if ((flags & ICTIMESYNCFLAG_SYNC) != 0) {
 139                 do_adj_guesttime(hosttime);
 140                 return;
 141         }
 142
 143         if ((flags & ICTIMESYNCFLAG_SAMPLE) != 0 && scnt > 0) {
 144                 scnt--;
 145                 do_adj_guesttime(hosttime);
 146         }
 147 }
 148
 149 /*
 150  * Time Sync Channel message handler.
 151  */
 152 static void timesync_onchannelcallback(void *context)
 153 {
 154         struct vmbus_channel *channel = context;
 155         u8 *buf;
 156         u32 buflen, recvlen;
 157         u64 requestid;
 158         struct icmsg_hdr *icmsghdrp;
 159         struct ictimesync_data *timedatap;
 160
 161         DPRINT_ENTER(VMBUS);
 162
 163         buflen = PAGE_SIZE;
 164         buf = kmalloc(buflen, GFP_ATOMIC);
 165
 166         VmbusChannelRecvPacket(channel, buf, buflen, &recvlen, &requestid);
 167
 168         if (recvlen > 0) {
 169                 DPRINT_DBG(VMBUS, "timesync packet: recvlen=%d, requestid=%lld",
 170                         recvlen, requestid);
 171
 172                 icmsghdrp = (struct icmsg_hdr *)&buf[
 173                                 sizeof(struct vmbuspipe_hdr)];
 174
 175                 if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) {
 176                         prep_negotiate_resp(icmsghdrp, NULL, buf);
 177                 } else {
 178                         timedatap = (struct ictimesync_data *)&buf[
 179                                 sizeof(struct vmbuspipe_hdr) +
 180                                 sizeof(struct icmsg_hdr)];
 181                         adj_guesttime(timedatap->parenttime, timedatap->flags);
 182                 }
 183
 184                 icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION
 185                         | ICMSGHDRFLAG_RESPONSE;
 186
 187                 VmbusChannelSendPacket(channel, buf,
 188                                 recvlen, requestid,
 189                                 VmbusPacketTypeDataInBand, 0);
 190         }
 191
 192         kfree(buf);
 193
 194         DPRINT_EXIT(VMBUS);
 195 }
 196
 197 /*
 198  * Heartbeat functionality.
 199  * Every two seconds, Hyper-V send us a heartbeat request message.
 200  * we respond to this message, and Hyper-V knows we are alive.
 201  */
 202 static void heartbeat_onchannelcallback(void *context)
 203 {
 204         struct vmbus_channel *channel = context;
 205         u8 *buf;
 206         u32 buflen, recvlen;
 207         u64 requestid;
 208         struct icmsg_hdr *icmsghdrp;
 209         struct heartbeat_msg_data *heartbeat_msg;
 210
 211         DPRINT_ENTER(VMBUS);
 212
 213         buflen = PAGE_SIZE;
 214         buf = kmalloc(buflen, GFP_ATOMIC);
 215
 216         VmbusChannelRecvPacket(channel, buf, buflen, &recvlen, &requestid);
 217
 218         if (recvlen > 0) {
 219                 DPRINT_DBG(VMBUS, "heartbeat packet: len=%d, requestid=%lld",
 220                            recvlen, requestid);
 221
 222                 icmsghdrp = (struct icmsg_hdr *)&buf[
 223                         sizeof(struct vmbuspipe_hdr)];
 224
 225                 icmsghdrp = (struct icmsg_hdr *)&buf[
 226                                 sizeof(struct vmbuspipe_hdr)];
 227
 228                 if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) {
 229                         prep_negotiate_resp(icmsghdrp, NULL, buf);
 230                 } else {
 231                         heartbeat_msg = (struct heartbeat_msg_data *)&buf[
 232                                 sizeof(struct vmbuspipe_hdr) +
 233                                 sizeof(struct icmsg_hdr)];
 234
 235                         DPRINT_DBG(VMBUS, "heartbeat seq = %lld",
 236                                    heartbeat_msg->seq_num);
 237
 238                         heartbeat_msg->seq_num += 1;
 239                 }
 240
 241                 icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION
 242                         | ICMSGHDRFLAG_RESPONSE;
 243
 244                 VmbusChannelSendPacket(channel, buf,
 245                                        recvlen, requestid,
 246                                        VmbusPacketTypeDataInBand, 0);
 247         }
 248
 249         kfree(buf);
 250
 251         DPRINT_EXIT(VMBUS);
 252 }
 253
 254 static int __init init_hyperv_utils(void)
 255 {
 256         printk(KERN_INFO "Registering HyperV Utility Driver\n");
 257
 258         hv_cb_utils[HV_SHUTDOWN_MSG].channel->OnChannelCallback =
 259                 &shutdown_onchannelcallback;
 260         hv_cb_utils[HV_SHUTDOWN_MSG].callback = &shutdown_onchannelcallback;
 261
 262         hv_cb_utils[HV_TIMESYNC_MSG].channel->OnChannelCallback =
 263                 &timesync_onchannelcallback;
 264         hv_cb_utils[HV_TIMESYNC_MSG].callback = &timesync_onchannelcallback;
 265
 266         hv_cb_utils[HV_HEARTBEAT_MSG].channel->OnChannelCallback =
 267                 &heartbeat_onchannelcallback;
 268         hv_cb_utils[HV_HEARTBEAT_MSG].callback = &heartbeat_onchannelcallback;
 269
 270         return 0;
 271 }
 272
 273 static void exit_hyperv_utils(void)
 274 {
 275         printk(KERN_INFO "De-Registered HyperV Utility Driver\n");
 276
 277         hv_cb_utils[HV_SHUTDOWN_MSG].channel->OnChannelCallback =
 278                 &chn_cb_negotiate;
 279         hv_cb_utils[HV_SHUTDOWN_MSG].callback = &chn_cb_negotiate;
 280
 281         hv_cb_utils[HV_TIMESYNC_MSG].channel->OnChannelCallback =
 282                 &chn_cb_negotiate;
 283         hv_cb_utils[HV_TIMESYNC_MSG].callback = &chn_cb_negotiate;
 284
 285         hv_cb_utils[HV_HEARTBEAT_MSG].channel->OnChannelCallback =
 286                 &chn_cb_negotiate;
 287         hv_cb_utils[HV_HEARTBEAT_MSG].callback = &chn_cb_negotiate;
 288 }
 289
 290 module_init(init_hyperv_utils);
 291 module_exit(exit_hyperv_utils);
 292
 293 MODULE_DESCRIPTION("Hyper-V Utilities");
 294 MODULE_VERSION(HV_DRV_VERSION);
 295 MODULE_LICENSE("GPL");