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 #include <linux/dmi.h>
  30 #include <linux/pci.h>
  31
  32 #include "hyperv.h"
  33 #include "hv_kvp.h"
  34
  35 static u8 *shut_txf_buf;
  36 static u8 *time_txf_buf;
  37 static u8 *hbeat_txf_buf;
  38
  39 static void shutdown_onchannelcallback(void *context)
  40 {
  41         struct vmbus_channel *channel = context;
  42         u32 recvlen;
  43         u64 requestid;
  44         u8  execute_shutdown = false;
  45
  46         struct shutdown_msg_data *shutdown_msg;
  47
  48         struct icmsg_hdr *icmsghdrp;
  49         struct icmsg_negotiate *negop = NULL;
  50
  51         vmbus_recvpacket(channel, shut_txf_buf,
  52                          PAGE_SIZE, &recvlen, &requestid);
  53
  54         if (recvlen > 0) {
  55                 icmsghdrp = (struct icmsg_hdr *)&shut_txf_buf[
  56                         sizeof(struct vmbuspipe_hdr)];
  57
  58                 if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) {
  59                         prep_negotiate_resp(icmsghdrp, negop, shut_txf_buf);
  60                 } else {
  61                         shutdown_msg =
  62                                 (struct shutdown_msg_data *)&shut_txf_buf[
  63                                         sizeof(struct vmbuspipe_hdr) +
  64                                         sizeof(struct icmsg_hdr)];
  65
  66                         switch (shutdown_msg->flags) {
  67                         case 0:
  68                         case 1:
  69                                 icmsghdrp->status = HV_S_OK;
  70                                 execute_shutdown = true;
  71
  72                                 pr_info("Shutdown request received -"
  73                                             " graceful shutdown initiated\n");
  74                                 break;
  75                         default:
  76                                 icmsghdrp->status = HV_E_FAIL;
  77                                 execute_shutdown = false;
  78
  79                                 pr_info("Shutdown request received -"
  80                                             " Invalid request\n");
  81                                 break;
  82                         }
  83                 }
  84
  85                 icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION
  86                         | ICMSGHDRFLAG_RESPONSE;
  87
  88                 vmbus_sendpacket(channel, shut_txf_buf,
  89                                        recvlen, requestid,
  90                                        VM_PKT_DATA_INBAND, 0);
  91         }
  92
  93         if (execute_shutdown == true)
  94                 orderly_poweroff(false);
  95 }
  96
  97 /*
  98  * Set guest time to host UTC time.
  99  */
 100 static inline void do_adj_guesttime(u64 hosttime)
 101 {
 102         s64 host_tns;
 103         struct timespec host_ts;
 104
 105         host_tns = (hosttime - WLTIMEDELTA) * 100;
 106         host_ts = ns_to_timespec(host_tns);
 107
 108         do_settimeofday(&host_ts);
 109 }
 110
 111 /*
 112  * Synchronize time with host after reboot, restore, etc.
 113  *
 114  * ICTIMESYNCFLAG_SYNC flag bit indicates reboot, restore events of the VM.
 115  * After reboot the flag ICTIMESYNCFLAG_SYNC is included in the first time
 116  * message after the timesync channel is opened. Since the hv_utils module is
 117  * loaded after hv_vmbus, the first message is usually missed. The other
 118  * thing is, systime is automatically set to emulated hardware clock which may
 119  * not be UTC time or in the same time zone. So, to override these effects, we
 120  * use the first 50 time samples for initial system time setting.
 121  */
 122 static inline void adj_guesttime(u64 hosttime, u8 flags)
 123 {
 124         static s32 scnt = 50;
 125
 126         if ((flags & ICTIMESYNCFLAG_SYNC) != 0) {
 127                 do_adj_guesttime(hosttime);
 128                 return;
 129         }
 130
 131         if ((flags & ICTIMESYNCFLAG_SAMPLE) != 0 && scnt > 0) {
 132                 scnt--;
 133                 do_adj_guesttime(hosttime);
 134         }
 135 }
 136
 137 /*
 138  * Time Sync Channel message handler.
 139  */
 140 static void timesync_onchannelcallback(void *context)
 141 {
 142         struct vmbus_channel *channel = context;
 143         u32 recvlen;
 144         u64 requestid;
 145         struct icmsg_hdr *icmsghdrp;
 146         struct ictimesync_data *timedatap;
 147
 148         vmbus_recvpacket(channel, time_txf_buf,
 149                          PAGE_SIZE, &recvlen, &requestid);
 150
 151         if (recvlen > 0) {
 152                 icmsghdrp = (struct icmsg_hdr *)&time_txf_buf[
 153                                 sizeof(struct vmbuspipe_hdr)];
 154
 155                 if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) {
 156                         prep_negotiate_resp(icmsghdrp, NULL, time_txf_buf);
 157                 } else {
 158                         timedatap = (struct ictimesync_data *)&time_txf_buf[
 159                                 sizeof(struct vmbuspipe_hdr) +
 160                                 sizeof(struct icmsg_hdr)];
 161                         adj_guesttime(timedatap->parenttime, timedatap->flags);
 162                 }
 163
 164                 icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION
 165                         | ICMSGHDRFLAG_RESPONSE;
 166
 167                 vmbus_sendpacket(channel, time_txf_buf,
 168                                 recvlen, requestid,
 169                                 VM_PKT_DATA_INBAND, 0);
 170         }
 171 }
 172
 173 /*
 174  * Heartbeat functionality.
 175  * Every two seconds, Hyper-V send us a heartbeat request message.
 176  * we respond to this message, and Hyper-V knows we are alive.
 177  */
 178 static void heartbeat_onchannelcallback(void *context)
 179 {
 180         struct vmbus_channel *channel = context;
 181         u32 recvlen;
 182         u64 requestid;
 183         struct icmsg_hdr *icmsghdrp;
 184         struct heartbeat_msg_data *heartbeat_msg;
 185
 186         vmbus_recvpacket(channel, hbeat_txf_buf,
 187                          PAGE_SIZE, &recvlen, &requestid);
 188
 189         if (recvlen > 0) {
 190                 icmsghdrp = (struct icmsg_hdr *)&hbeat_txf_buf[
 191                                 sizeof(struct vmbuspipe_hdr)];
 192
 193                 if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) {
 194                         prep_negotiate_resp(icmsghdrp, NULL, hbeat_txf_buf);
 195                 } else {
 196                         heartbeat_msg =
 197                                 (struct heartbeat_msg_data *)&hbeat_txf_buf[
 198                                         sizeof(struct vmbuspipe_hdr) +
 199                                         sizeof(struct icmsg_hdr)];
 200
 201                         heartbeat_msg->seq_num += 1;
 202                 }
 203
 204                 icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION
 205                         | ICMSGHDRFLAG_RESPONSE;
 206
 207                 vmbus_sendpacket(channel, hbeat_txf_buf,
 208                                        recvlen, requestid,
 209                                        VM_PKT_DATA_INBAND, 0);
 210         }
 211 }
 212
 213 static const struct pci_device_id __initconst
 214 hv_utils_pci_table[] __maybe_unused = {
 215         { PCI_DEVICE(0x1414, 0x5353) }, /* Hyper-V emulated VGA controller */
 216         { 0 }
 217 };
 218 MODULE_DEVICE_TABLE(pci, hv_utils_pci_table);
 219
 220
 221 static const struct dmi_system_id __initconst
 222 hv_utils_dmi_table[] __maybe_unused  = {
 223         {
 224                 .ident = "Hyper-V",
 225                 .matches = {
 226                         DMI_MATCH(DMI_SYS_VENDOR, "Microsoft Corporation"),
 227                         DMI_MATCH(DMI_PRODUCT_NAME, "Virtual Machine"),
 228                         DMI_MATCH(DMI_BOARD_NAME, "Virtual Machine"),
 229                 },
 230         },
 231         { },
 232 };
 233 MODULE_DEVICE_TABLE(dmi, hv_utils_dmi_table);
 234
 235
 236 static int __init init_hyperv_utils(void)
 237 {
 238         pr_info("Registering HyperV Utility Driver\n");
 239
 240         if (hv_kvp_init())
 241                 return -ENODEV;
 242
 243
 244         if (!dmi_check_system(hv_utils_dmi_table))
 245                 return -ENODEV;
 246
 247         shut_txf_buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
 248         time_txf_buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
 249         hbeat_txf_buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
 250
 251         if (!shut_txf_buf || !time_txf_buf || !hbeat_txf_buf) {
 252                 pr_info("Unable to allocate memory for receive buffer\n");
 253                 kfree(shut_txf_buf);
 254                 kfree(time_txf_buf);
 255                 kfree(hbeat_txf_buf);
 256                 return -ENOMEM;
 257         }
 258
 259         hv_cb_utils[HV_SHUTDOWN_MSG].callback = &shutdown_onchannelcallback;
 260
 261         hv_cb_utils[HV_TIMESYNC_MSG].callback = &timesync_onchannelcallback;
 262
 263         hv_cb_utils[HV_HEARTBEAT_MSG].callback = &heartbeat_onchannelcallback;
 264
 265         hv_cb_utils[HV_KVP_MSG].callback = &hv_kvp_onchannelcallback;
 266
 267         return 0;
 268 }
 269
 270 static void exit_hyperv_utils(void)
 271 {
 272         pr_info("De-Registered HyperV Utility Driver\n");
 273
 274         if (hv_cb_utils[HV_SHUTDOWN_MSG].channel != NULL)
 275                 hv_cb_utils[HV_SHUTDOWN_MSG].channel->onchannel_callback =
 276                         &chn_cb_negotiate;
 277         hv_cb_utils[HV_SHUTDOWN_MSG].callback = NULL;
 278
 279         if (hv_cb_utils[HV_TIMESYNC_MSG].channel != NULL)
 280                 hv_cb_utils[HV_TIMESYNC_MSG].channel->onchannel_callback =
 281                         &chn_cb_negotiate;
 282         hv_cb_utils[HV_TIMESYNC_MSG].callback = NULL;
 283
 284         if (hv_cb_utils[HV_HEARTBEAT_MSG].channel != NULL)
 285                 hv_cb_utils[HV_HEARTBEAT_MSG].channel->onchannel_callback =
 286                         &chn_cb_negotiate;
 287         hv_cb_utils[HV_HEARTBEAT_MSG].callback = NULL;
 288
 289         if (hv_cb_utils[HV_KVP_MSG].channel != NULL)
 290                 hv_cb_utils[HV_KVP_MSG].channel->onchannel_callback =
 291                         &chn_cb_negotiate;
 292         hv_cb_utils[HV_KVP_MSG].callback = NULL;
 293
 294         hv_kvp_deinit();
 295
 296         kfree(shut_txf_buf);
 297         kfree(time_txf_buf);
 298         kfree(hbeat_txf_buf);
 299 }
 300
 301 module_init(init_hyperv_utils);
 302 module_exit(exit_hyperv_utils);
 303
 304 MODULE_DESCRIPTION("Hyper-V Utilities");
 305 MODULE_VERSION(HV_DRV_VERSION);
 306 MODULE_LICENSE("GPL");