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