linux/drivers/hv/hv_util.c
Stephen Hemminger b71e328297 vmbus: add direct isr callback mode
Change the simple boolean batched_reading into a tri-value.
For future NAPI support in netvsc driver, the callback needs to
occur directly in interrupt handler.

Batched mode is also changed to disable host interrupts immediately
in interrupt routine (to avoid unnecessary host signals), and the
tasklet is rescheduled if more data is detected.

Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-02-14 10:20:35 -08:00

636 lines
15 KiB
C

/*
* 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>
#include <linux/clockchips.h>
#include <linux/ptp_clock_kernel.h>
#include <asm/mshyperv.h>
#include "hyperv_vmbus.h"
#define SD_MAJOR 3
#define SD_MINOR 0
#define SD_VERSION (SD_MAJOR << 16 | SD_MINOR)
#define SD_MAJOR_1 1
#define SD_VERSION_1 (SD_MAJOR_1 << 16 | SD_MINOR)
#define TS_MAJOR 4
#define TS_MINOR 0
#define TS_VERSION (TS_MAJOR << 16 | TS_MINOR)
#define TS_MAJOR_1 1
#define TS_VERSION_1 (TS_MAJOR_1 << 16 | TS_MINOR)
#define TS_MAJOR_3 3
#define TS_VERSION_3 (TS_MAJOR_3 << 16 | TS_MINOR)
#define HB_MAJOR 3
#define HB_MINOR 0
#define HB_VERSION (HB_MAJOR << 16 | HB_MINOR)
#define HB_MAJOR_1 1
#define HB_VERSION_1 (HB_MAJOR_1 << 16 | HB_MINOR)
static int sd_srv_version;
static int ts_srv_version;
static int hb_srv_version;
#define SD_VER_COUNT 2
static const int sd_versions[] = {
SD_VERSION,
SD_VERSION_1
};
#define TS_VER_COUNT 3
static const int ts_versions[] = {
TS_VERSION,
TS_VERSION_3,
TS_VERSION_1
};
#define HB_VER_COUNT 2
static const int hb_versions[] = {
HB_VERSION,
HB_VERSION_1
};
#define FW_VER_COUNT 2
static const int fw_versions[] = {
UTIL_FW_VERSION,
UTIL_WS2K8_FW_VERSION
};
static void shutdown_onchannelcallback(void *context);
static struct hv_util_service util_shutdown = {
.util_cb = shutdown_onchannelcallback,
};
static int hv_timesync_init(struct hv_util_service *srv);
static void hv_timesync_deinit(void);
static void timesync_onchannelcallback(void *context);
static struct hv_util_service util_timesynch = {
.util_cb = timesync_onchannelcallback,
.util_init = hv_timesync_init,
.util_deinit = hv_timesync_deinit,
};
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 struct hv_util_service util_vss = {
.util_cb = hv_vss_onchannelcallback,
.util_init = hv_vss_init,
.util_deinit = hv_vss_deinit,
};
static struct hv_util_service util_fcopy = {
.util_cb = hv_fcopy_onchannelcallback,
.util_init = hv_fcopy_init,
.util_deinit = hv_fcopy_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;
bool execute_shutdown = false;
u8 *shut_txf_buf = util_shutdown.recv_buffer;
struct shutdown_msg_data *shutdown_msg;
struct icmsg_hdr *icmsghdrp;
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) {
if (vmbus_prep_negotiate_resp(icmsghdrp, shut_txf_buf,
fw_versions, FW_VER_COUNT,
sd_versions, SD_VER_COUNT,
NULL, &sd_srv_version)) {
pr_info("Shutdown IC version %d.%d\n",
sd_srv_version >> 16,
sd_srv_version & 0xFFFF);
}
} 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 the host time in a process context.
*/
struct adj_time_work {
struct work_struct work;
u64 host_time;
u64 ref_time;
u8 flags;
};
static void hv_set_host_time(struct work_struct *work)
{
struct adj_time_work *wrk;
struct timespec64 host_ts;
u64 reftime, newtime;
wrk = container_of(work, struct adj_time_work, work);
reftime = hyperv_cs->read(hyperv_cs);
newtime = wrk->host_time + (reftime - wrk->ref_time);
host_ts = ns_to_timespec64((newtime - WLTIMEDELTA) * 100);
do_settimeofday64(&host_ts);
}
/*
* 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. This bit is
* considered a hard request to discipline the clock.
*
* ICTIMESYNCFLAG_SAMPLE bit indicates a time sample from host. This is
* typically used as a hint to the guest. The guest is under no obligation
* to discipline the clock.
*/
static struct adj_time_work wrk;
/*
* The last time sample, received from the host. PTP device responds to
* requests by using this data and the current partition-wide time reference
* count.
*/
static struct {
u64 host_time;
u64 ref_time;
struct system_time_snapshot snap;
spinlock_t lock;
} host_ts;
static inline void adj_guesttime(u64 hosttime, u64 reftime, u8 adj_flags)
{
unsigned long flags;
u64 cur_reftime;
/*
* This check is safe since we are executing in the
* interrupt context and time synch messages are always
* delivered on the same CPU.
*/
if (adj_flags & ICTIMESYNCFLAG_SYNC) {
/* Queue a job to do do_settimeofday64() */
if (work_pending(&wrk.work))
return;
wrk.host_time = hosttime;
wrk.ref_time = reftime;
wrk.flags = adj_flags;
schedule_work(&wrk.work);
} else {
/*
* Save the adjusted time sample from the host and the snapshot
* of the current system time for PTP device.
*/
spin_lock_irqsave(&host_ts.lock, flags);
cur_reftime = hyperv_cs->read(hyperv_cs);
host_ts.host_time = hosttime;
host_ts.ref_time = cur_reftime;
ktime_get_snapshot(&host_ts.snap);
/*
* TimeSync v4 messages contain reference time (guest's Hyper-V
* clocksource read when the time sample was generated), we can
* improve the precision by adding the delta between now and the
* time of generation.
*/
if (ts_srv_version > TS_VERSION_3)
host_ts.host_time += (cur_reftime - reftime);
spin_unlock_irqrestore(&host_ts.lock, flags);
}
}
/*
* 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;
struct ictimesync_ref_data *refdata;
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) {
if (vmbus_prep_negotiate_resp(icmsghdrp, time_txf_buf,
fw_versions, FW_VER_COUNT,
ts_versions, TS_VER_COUNT,
NULL, &ts_srv_version)) {
pr_info("TimeSync IC version %d.%d\n",
ts_srv_version >> 16,
ts_srv_version & 0xFFFF);
}
} else {
if (ts_srv_version > TS_VERSION_3) {
refdata = (struct ictimesync_ref_data *)
&time_txf_buf[
sizeof(struct vmbuspipe_hdr) +
sizeof(struct icmsg_hdr)];
adj_guesttime(refdata->parenttime,
refdata->vmreferencetime,
refdata->flags);
} else {
timedatap = (struct ictimesync_data *)
&time_txf_buf[
sizeof(struct vmbuspipe_hdr) +
sizeof(struct icmsg_hdr)];
adj_guesttime(timedatap->parenttime,
0,
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;
while (1) {
vmbus_recvpacket(channel, hbeat_txf_buf,
PAGE_SIZE, &recvlen, &requestid);
if (!recvlen)
break;
icmsghdrp = (struct icmsg_hdr *)&hbeat_txf_buf[
sizeof(struct vmbuspipe_hdr)];
if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) {
if (vmbus_prep_negotiate_resp(icmsghdrp,
hbeat_txf_buf,
fw_versions, FW_VER_COUNT,
hb_versions, HB_VER_COUNT,
NULL, &hb_srv_version)) {
pr_info("Heartbeat IC version %d.%d\n",
hb_srv_version >> 16,
hb_srv_version & 0xFFFF);
}
} 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 * 4, GFP_KERNEL);
if (!srv->recv_buffer)
return -ENOMEM;
srv->channel = dev->channel;
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_mode(dev->channel, HV_CALL_DIRECT);
hv_set_drvdata(dev, srv);
ret = vmbus_open(dev->channel, 4 * PAGE_SIZE, 4 * PAGE_SIZE, NULL, 0,
srv->util_cb, dev->channel);
if (ret)
goto error;
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);
if (srv->util_deinit)
srv->util_deinit();
vmbus_close(dev->channel);
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
},
/* VSS GUID */
{ HV_VSS_GUID,
.driver_data = (unsigned long)&util_vss
},
/* File copy GUID */
{ HV_FCOPY_GUID,
.driver_data = (unsigned long)&util_fcopy
},
{ },
};
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 hv_ptp_enable(struct ptp_clock_info *info,
struct ptp_clock_request *request, int on)
{
return -EOPNOTSUPP;
}
static int hv_ptp_settime(struct ptp_clock_info *p, const struct timespec64 *ts)
{
return -EOPNOTSUPP;
}
static int hv_ptp_adjfreq(struct ptp_clock_info *ptp, s32 delta)
{
return -EOPNOTSUPP;
}
static int hv_ptp_adjtime(struct ptp_clock_info *ptp, s64 delta)
{
return -EOPNOTSUPP;
}
static int hv_ptp_gettime(struct ptp_clock_info *info, struct timespec64 *ts)
{
unsigned long flags;
u64 newtime, reftime;
spin_lock_irqsave(&host_ts.lock, flags);
reftime = hyperv_cs->read(hyperv_cs);
newtime = host_ts.host_time + (reftime - host_ts.ref_time);
*ts = ns_to_timespec64((newtime - WLTIMEDELTA) * 100);
spin_unlock_irqrestore(&host_ts.lock, flags);
return 0;
}
static int hv_ptp_get_syncdevicetime(ktime_t *device,
struct system_counterval_t *system,
void *ctx)
{
system->cs = hyperv_cs;
system->cycles = host_ts.ref_time;
*device = ns_to_ktime((host_ts.host_time - WLTIMEDELTA) * 100);
return 0;
}
static int hv_ptp_getcrosststamp(struct ptp_clock_info *ptp,
struct system_device_crosststamp *xtstamp)
{
unsigned long flags;
int ret;
spin_lock_irqsave(&host_ts.lock, flags);
/*
* host_ts contains the last time sample from the host and the snapshot
* of system time. We don't need to calculate the time delta between
* the reception and now as get_device_system_crosststamp() does the
* required interpolation.
*/
ret = get_device_system_crosststamp(hv_ptp_get_syncdevicetime,
NULL, &host_ts.snap, xtstamp);
spin_unlock_irqrestore(&host_ts.lock, flags);
return ret;
}
static struct ptp_clock_info ptp_hyperv_info = {
.name = "hyperv",
.enable = hv_ptp_enable,
.adjtime = hv_ptp_adjtime,
.adjfreq = hv_ptp_adjfreq,
.gettime64 = hv_ptp_gettime,
.getcrosststamp = hv_ptp_getcrosststamp,
.settime64 = hv_ptp_settime,
.owner = THIS_MODULE,
};
static struct ptp_clock *hv_ptp_clock;
static int hv_timesync_init(struct hv_util_service *srv)
{
/* TimeSync requires Hyper-V clocksource. */
if (!hyperv_cs)
return -ENODEV;
INIT_WORK(&wrk.work, hv_set_host_time);
/*
* ptp_clock_register() returns NULL when CONFIG_PTP_1588_CLOCK is
* disabled but the driver is still useful without the PTP device
* as it still handles the ICTIMESYNCFLAG_SYNC case.
*/
hv_ptp_clock = ptp_clock_register(&ptp_hyperv_info, NULL);
if (IS_ERR_OR_NULL(hv_ptp_clock)) {
pr_err("cannot register PTP clock: %ld\n",
PTR_ERR(hv_ptp_clock));
hv_ptp_clock = NULL;
}
return 0;
}
static void hv_timesync_deinit(void)
{
if (hv_ptp_clock)
ptp_clock_unregister(hv_ptp_clock);
cancel_work_sync(&wrk.work);
}
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_LICENSE("GPL");