/*
* Copyright (c) 2010, Microsoft Corporation.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2, as published by the Free Software Foundation.
*
* This program is distributed in the hope it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*
* You should have received a copy of the GNU General Public License along with
* this program; if not, write to the Free Software Foundation, Inc., 59 Temple
* Place - Suite 330, Boston, MA 02111-1307 USA.
*
* Authors:
* Haiyang Zhang <haiyangz@microsoft.com>
* Hank Janssen <hjanssen@microsoft.com>
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/sysctl.h>
#include <linux/reboot.h>
#include <linux/hyperv.h>
static void shutdown_onchannelcallback(void *context);
static struct hv_util_service util_shutdown = {
.util_cb = shutdown_onchannelcallback,
};
static void timesync_onchannelcallback(void *context);
static struct hv_util_service util_timesynch = {
.util_cb = timesync_onchannelcallback,
};
static void heartbeat_onchannelcallback(void *context);
static struct hv_util_service util_heartbeat = {
.util_cb = heartbeat_onchannelcallback,
};
static struct hv_util_service util_kvp = {
.util_cb = hv_kvp_onchannelcallback,
.util_init = hv_kvp_init,
.util_deinit = hv_kvp_deinit,
};
static void perform_shutdown(struct work_struct *dummy)
{
orderly_poweroff(true);
}
/*
* Perform the shutdown operation in a thread context.
*/
static DECLARE_WORK(shutdown_work, perform_shutdown);
static void shutdown_onchannelcallback(void *context)
{
struct vmbus_channel *channel = context;
u32 recvlen;
u64 requestid;
u8 execute_shutdown = false;
u8 *shut_txf_buf = util_shutdown.recv_buffer;
struct shutdown_msg_data *shutdown_msg;
struct icmsg_hdr *icmsghdrp;
struct icmsg_negotiate *negop = NULL;
vmbus_recvpacket(channel, shut_txf_buf,
PAGE_SIZE, &recvlen, &requestid);
if (recvlen > 0) {
icmsghdrp = (struct icmsg_hdr *)&shut_txf_buf[
sizeof(struct vmbuspipe_hdr)];
if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) {
vmbus_prep_negotiate_resp(icmsghdrp, negop,
shut_txf_buf, MAX_SRV_VER, MAX_SRV_VER);
} else {
shutdown_msg =
(struct shutdown_msg_data *)&shut_txf_buf[
sizeof(struct vmbuspipe_hdr) +
sizeof(struct icmsg_hdr)];
switch (shutdown_msg->flags) {
case 0:
case 1:
icmsghdrp->status = HV_S_OK;
execute_shutdown = true;
pr_info("Shutdown request received -"
" graceful shutdown initiated\n");
break;
default:
icmsghdrp->status = HV_E_FAIL;
execute_shutdown = false;
pr_info("Shutdown request received -"
" Invalid request\n");
break;
}
}
icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION
| ICMSGHDRFLAG_RESPONSE;
vmbus_sendpacket(channel, shut_txf_buf,
recvlen, requestid,
VM_PKT_DATA_INBAND, 0);
}
if (execute_shutdown == true)
schedule_work(&shutdown_work);
}
/*
* Set guest time to host UTC time.
*/
static inline void do_adj_guesttime(u64 hosttime)
{
s64 host_tns;
struct timespec host_ts;
host_tns = (hosttime - WLTIMEDELTA) * 100;
host_ts = ns_to_timespec(host_tns);
do_settimeofday(&host_ts);
}
/*
* Set the host time in a process context.
*/
struct adj_time_work {
struct work_struct work;
u64 host_time;
};
static void hv_set_host_time(struct work_struct *work)
{
struct adj_time_work *wrk;
wrk = container_of(work, struct adj_time_work, work);
do_adj_guesttime(wrk->host_time);
kfree(wrk);
}
/*
* Synchronize time with host after reboot, restore, etc.
*
* ICTIMESYNCFLAG_SYNC flag bit indicates reboot, restore events of the VM.
* After reboot the flag ICTIMESYNCFLAG_SYNC is included in the first time
* message after the timesync channel is opened. Since the hv_utils module is
* loaded after hv_vmbus, the first message is usually missed. The other
* thing is, systime is automatically set to emulated hardware clock which may
* not be UTC time or in the same time zone. So, to override these effects, we
* use the first 50 time samples for initial system time setting.
*/
static inline void adj_guesttime(u64 hosttime, u8 flags)
{
struct adj_time_work *wrk;
static s32 scnt = 50;
wrk = kmalloc(sizeof(struct adj_time_work), GFP_ATOMIC);
if (wrk == NULL)
return;
wrk->host_time = hosttime;
if ((flags & ICTIMESYNCFLAG_SYNC) != 0) {
INIT_WORK(&wrk->work, hv_set_host_time);
schedule_work(&wrk->work);
return;
}
if ((flags & ICTIMESYNCFLAG_SAMPLE) != 0 && scnt > 0) {
scnt--;
INIT_WORK(&wrk->work, hv_set_host_time);
schedule_work(&wrk->work);
} else
kfree(wrk);
}
/*
* Time Sync Channel message handler.
*/
static void timesync_onchannelcallback(void *context)
{
struct vmbus_channel *channel = context;
u32 recvlen;
u64 requestid;
struct icmsg_hdr *icmsghdrp;
struct ictimesync_data *timedatap;
u8 *time_txf_buf = util_timesynch.recv_buffer;
vmbus_recvpacket(channel, time_txf_buf,
PAGE_SIZE, &recvlen, &requestid);
if (recvlen > 0) {
icmsghdrp = (struct icmsg_hdr *)&time_txf_buf[
sizeof(struct vmbuspipe_hdr)];
if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) {
vmbus_prep_negotiate_resp(icmsghdrp, NULL, time_txf_buf,
MAX_SRV_VER, MAX_SRV_VER);
} else {
timedatap = (struct ictimesync_data *)&time_txf_buf[
sizeof(struct vmbuspipe_hdr) +
sizeof(struct icmsg_hdr)];
adj_guesttime(timedatap->parenttime, timedatap->flags);
}
icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION
| ICMSGHDRFLAG_RESPONSE;
vmbus_sendpacket(channel, time_txf_buf,
recvlen, requestid,
VM_PKT_DATA_INBAND, 0);
}
}
/*
* Heartbeat functionality.
* Every two seconds, Hyper-V send us a heartbeat request message.
* we respond to this message, and Hyper-V knows we are alive.
*/
static void heartbeat_onchannelcallback(void *context)
{
struct vmbus_channel *channel = context;
u32 recvlen;
u64 requestid;
struct icmsg_hdr *icmsghdrp;
struct heartbeat_msg_data *heartbeat_msg;
u8 *hbeat_txf_buf = util_heartbeat.recv_buffer;
vmbus_recvpacket(channel, hbeat_txf_buf,
PAGE_SIZE, &recvlen, &requestid);
if (recvlen > 0) {
icmsghdrp = (struct icmsg_hdr *)&hbeat_txf_buf[
sizeof(struct vmbuspipe_hdr)];
if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) {
vmbus_prep_negotiate_resp(icmsghdrp, NULL,
hbeat_txf_buf, MAX_SRV_VER, MAX_SRV_VER);
} else {
heartbeat_msg =
(struct heartbeat_msg_data *)&hbeat_txf_buf[
sizeof(struct vmbuspipe_hdr) +
sizeof(struct icmsg_hdr)];
heartbeat_msg->seq_num += 1;
}
icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION
| ICMSGHDRFLAG_RESPONSE;
vmbus_sendpacket(channel, hbeat_txf_buf,
recvlen, requestid,
VM_PKT_DATA_INBAND, 0);
}
}
static int util_probe(struct hv_device *dev,
const struct hv_vmbus_device_id *dev_id)
{
struct hv_util_service *srv =
(struct hv_util_service *)dev_id->driver_data;
int ret;
srv->recv_buffer = kmalloc(PAGE_SIZE * 2, GFP_KERNEL);
if (!srv->recv_buffer)
return -ENOMEM;
if (srv->util_init) {
ret = srv->util_init(srv);
if (ret) {
ret = -ENODEV;
goto error1;
}
}
/*
* The set of services managed by the util driver are not performance
* critical and do not need batched reading. Furthermore, some services
* such as KVP can only handle one message from the host at a time.
* Turn off batched reading for all util drivers before we open the
* channel.
*/
set_channel_read_state(dev->channel, false);
ret = vmbus_open(dev->channel, 4 * PAGE_SIZE, 4 * PAGE_SIZE, NULL, 0,
srv->util_cb, dev->channel);
if (ret)
goto error;
hv_set_drvdata(dev, srv);
return 0;
error:
if (srv->util_deinit)
srv->util_deinit();
error1:
kfree(srv->recv_buffer);
return ret;
}
static int util_remove(struct hv_device *dev)
{
struct hv_util_service *srv = hv_get_drvdata(dev);
vmbus_close(dev->channel);
if (srv->util_deinit)
srv->util_deinit();
kfree(srv->recv_buffer);
return 0;
}
static const struct hv_vmbus_device_id id_table[] = {
/* Shutdown guid */
{ HV_SHUTDOWN_GUID,
.driver_data = (unsigned long)&util_shutdown
},
/* Time synch guid */
{ HV_TS_GUID,
.driver_data = (unsigned long)&util_timesynch
},
/* Heartbeat guid */
{ HV_HEART_BEAT_GUID,
.driver_data = (unsigned long)&util_heartbeat
},
/* KVP guid */
{ HV_KVP_GUID,
.driver_data = (unsigned long)&util_kvp
},
{ },
};
MODULE_DEVICE_TABLE(vmbus, id_table);
/* The one and only one */
static struct hv_driver util_drv = {
.name = "hv_util",
.id_table = id_table,
.probe = util_probe,
.remove = util_remove,
};
static int __init init_hyperv_utils(void)
{
pr_info("Registering HyperV Utility Driver\n");
return vmbus_driver_register(&util_drv);
}
static void exit_hyperv_utils(void)
{
pr_info("De-Registered HyperV Utility Driver\n");
vmbus_driver_unregister(&util_drv);
}
module_init(init_hyperv_utils);
module_exit(exit_hyperv_utils);
MODULE_DESCRIPTION("Hyper-V Utilities");
MODULE_VERSION(HV_DRV_VERSION);
MODULE_LICENSE("GPL");
