// SPDX-License-Identifier: GPL-2.0-only /* * Copyright (c) 2010, Microsoft Corporation. * * 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 <clocksource/hyperv_timer.h> #include <asm/mshyperv.h> #include "hyperv_vmbus.h" #define SD_MAJOR 3 #define SD_MINOR 0 #define SD_MINOR_1 1 #define SD_MINOR_2 2 #define SD_VERSION_3_1 (SD_MAJOR << 16 | SD_MINOR_1) #define SD_VERSION_3_2 (SD_MAJOR << 16 | SD_MINOR_2) #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 4 static const int sd_versions[] = { SD_VERSION_3_2, SD_VERSION_3_1, 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 }; /* * Send the "hibernate" udev event in a thread context. */ struct hibernate_work_context { struct work_struct work; struct hv_device *dev; }; static struct hibernate_work_context hibernate_context; static bool hibernation_supported; static void send_hibernate_uevent(struct work_struct *work) { char *uevent_env[2] = { "EVENT=hibernate", NULL }; struct hibernate_work_context *ctx; ctx = container_of(work, struct hibernate_work_context, work); kobject_uevent_env(&ctx->dev->device.kobj, KOBJ_CHANGE, uevent_env); pr_info("Sent hibernation uevent\n"); } static int hv_shutdown_init(struct hv_util_service *srv) { struct vmbus_channel *channel = srv->channel; INIT_WORK(&hibernate_context.work, send_hibernate_uevent); hibernate_context.dev = channel->device_obj; hibernation_supported = hv_is_hibernation_supported(); return 0; } static void shutdown_onchannelcallback(void *context); static struct hv_util_service util_shutdown = { .util_cb = shutdown_onchannelcallback, .util_init = hv_shutdown_init, }; static int hv_timesync_init(struct hv_util_service *srv); static int hv_timesync_pre_suspend(void); 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_pre_suspend = hv_timesync_pre_suspend, .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_pre_suspend = hv_kvp_pre_suspend, .util_pre_resume = hv_kvp_pre_resume, .util_deinit = hv_kvp_deinit, }; static struct hv_util_service util_vss = { .util_cb = hv_vss_onchannelcallback, .util_init = hv_vss_init, .util_pre_suspend = hv_vss_pre_suspend, .util_pre_resume = hv_vss_pre_resume, .util_deinit = hv_vss_deinit, }; static struct hv_util_service util_fcopy = { .util_cb = hv_fcopy_onchannelcallback, .util_init = hv_fcopy_init, .util_pre_suspend = hv_fcopy_pre_suspend, .util_pre_resume = hv_fcopy_pre_resume, .util_deinit = hv_fcopy_deinit, }; static void perform_shutdown(struct work_struct *dummy) { orderly_poweroff(true); } static void perform_restart(struct work_struct *dummy) { orderly_reboot(); } /* * Perform the shutdown operation in a thread context. */ static DECLARE_WORK(shutdown_work, perform_shutdown); /* * Perform the restart operation in a thread context. */ static DECLARE_WORK(restart_work, perform_restart); static void shutdown_onchannelcallback(void *context) { struct vmbus_channel *channel = context; struct work_struct *work = NULL; u32 recvlen; u64 requestid; u8 *shut_txf_buf = util_shutdown.recv_buffer; struct shutdown_msg_data *shutdown_msg; struct icmsg_hdr *icmsghdrp; vmbus_recvpacket(channel, shut_txf_buf, HV_HYP_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)]; /* * shutdown_msg->flags can be 0(shut down), 2(reboot), * or 4(hibernate). It may bitwise-OR 1, which means * performing the request by force. Linux always tries * to perform the request by force. */ switch (shutdown_msg->flags) { case 0: case 1: icmsghdrp->status = HV_S_OK; work = &shutdown_work; pr_info("Shutdown request received -" " graceful shutdown initiated\n"); break; case 2: case 3: icmsghdrp->status = HV_S_OK; work = &restart_work; pr_info("Restart request received -" " graceful restart initiated\n"); break; case 4: case 5: pr_info("Hibernation request received\n"); icmsghdrp->status = hibernation_supported ? HV_S_OK : HV_E_FAIL; if (hibernation_supported) work = &hibernate_context.work; break; default: icmsghdrp->status = HV_E_FAIL; 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 (work) schedule_work(work); } /* * Set the host time in a process context. */ static struct work_struct adj_time_work; /* * 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; spinlock_t lock; } host_ts; static inline u64 reftime_to_ns(u64 reftime) { return (reftime - WLTIMEDELTA) * 100; } /* * Hard coded threshold for host timesync delay: 600 seconds */ static const u64 HOST_TIMESYNC_DELAY_THRESH = 600 * (u64)NSEC_PER_SEC; static int hv_get_adj_host_time(struct timespec64 *ts) { u64 newtime, reftime, timediff_adj; unsigned long flags; int ret = 0; spin_lock_irqsave(&host_ts.lock, flags); reftime = hv_read_reference_counter(); /* * We need to let the caller know that last update from host * is older than the max allowable threshold. clock_gettime() * and PTP ioctl do not have a documented error that we could * return for this specific case. Use ESTALE to report this. */ timediff_adj = reftime - host_ts.ref_time; if (timediff_adj * 100 > HOST_TIMESYNC_DELAY_THRESH) { pr_warn_once("TIMESYNC IC: Stale time stamp, %llu nsecs old\n", (timediff_adj * 100)); ret = -ESTALE; } newtime = host_ts.host_time + timediff_adj; *ts = ns_to_timespec64(reftime_to_ns(newtime)); spin_unlock_irqrestore(&host_ts.lock, flags); return ret; } static void hv_set_host_time(struct work_struct *work) { struct timespec64 ts; if (!hv_get_adj_host_time(&ts)) do_settimeofday64(&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 inline void adj_guesttime(u64 hosttime, u64 reftime, u8 adj_flags) { unsigned long flags; u64 cur_reftime; /* * Save the adjusted time sample from the host and the snapshot * of the current system time. */ spin_lock_irqsave(&host_ts.lock, flags); cur_reftime = hv_read_reference_counter(); host_ts.host_time = hosttime; host_ts.ref_time = cur_reftime; /* * 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. For older protocols we set * reftime == cur_reftime on call. */ host_ts.host_time += (cur_reftime - reftime); spin_unlock_irqrestore(&host_ts.lock, flags); /* Schedule work to do do_settimeofday64() */ if (adj_flags & ICTIMESYNCFLAG_SYNC) schedule_work(&adj_time_work); } /* * 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; /* * Drain the ring buffer and use the last packet to update * host_ts */ while (1) { int ret = vmbus_recvpacket(channel, time_txf_buf, HV_HYP_PAGE_SIZE, &recvlen, &requestid); if (ret) { pr_warn_once("TimeSync IC pkt recv failed (Err: %d)\n", ret); break; } if (!recvlen) break; 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, hv_read_reference_counter(), 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, HV_HYP_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(HV_HYP_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 * HV_HYP_PAGE_SIZE, 4 * HV_HYP_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; } /* * When we're in util_suspend(), all the userspace processes have been frozen * (refer to hibernate() -> freeze_processes()). The userspace is thawed only * after the whole resume procedure, including util_resume(), finishes. */ static int util_suspend(struct hv_device *dev) { struct hv_util_service *srv = hv_get_drvdata(dev); int ret = 0; if (srv->util_pre_suspend) { ret = srv->util_pre_suspend(); if (ret) return ret; } vmbus_close(dev->channel); return 0; } static int util_resume(struct hv_device *dev) { struct hv_util_service *srv = hv_get_drvdata(dev); int ret = 0; if (srv->util_pre_resume) { ret = srv->util_pre_resume(); if (ret) return ret; } ret = vmbus_open(dev->channel, 4 * HV_HYP_PAGE_SIZE, 4 * HV_HYP_PAGE_SIZE, NULL, 0, srv->util_cb, dev->channel); return ret; } 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_utils", .id_table = id_table, .probe = util_probe, .remove = util_remove, .suspend = util_suspend, .resume = util_resume, .driver = { .probe_type = PROBE_PREFER_ASYNCHRONOUS, }, }; 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) { return hv_get_adj_host_time(ts); } 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, .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 (!hv_read_reference_counter) return -ENODEV; spin_lock_init(&host_ts.lock); INIT_WORK(&adj_time_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_cancel_work(void) { cancel_work_sync(&adj_time_work); } static int hv_timesync_pre_suspend(void) { hv_timesync_cancel_work(); return 0; } static void hv_timesync_deinit(void) { if (hv_ptp_clock) ptp_clock_unregister(hv_ptp_clock); hv_timesync_cancel_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");