/* * virnodesuspend.c: Support for suspending a node (host machine) * * Copyright (C) 2011 Srivatsa S. Bhat * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * This library is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this library; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA * */ #include #include "virnodesuspend.h" #include "command.h" #include "threads.h" #include "datatypes.h" #include "memory.h" #include "logging.h" #include "virterror_internal.h" #define VIR_FROM_THIS VIR_FROM_NONE #define virNodeSuspendError(code, ...) \ virReportErrorHelper(VIR_FROM_NONE, code, __FILE__, \ __FUNCTION__, __LINE__, __VA_ARGS__) #define SUSPEND_DELAY 10 /* in seconds */ /* Give sufficient time for performing the suspend operation on the host */ #define MIN_TIME_REQ_FOR_SUSPEND 60 /* in seconds */ /* * Bitmask to hold the Power Management features supported by the host, * such as Suspend-to-RAM, Suspend-to-Disk, Hybrid-Suspend etc. */ static unsigned int hostPMFeatures; virMutex virNodeSuspendMutex; static bool aboutToSuspend; static void virNodeSuspendLock(void) { virMutexLock(&virNodeSuspendMutex); } static void virNodeSuspendUnlock(void) { virMutexUnlock(&virNodeSuspendMutex); } /** * virNodeSuspendInit: * * Get the system-wide sleep states supported by the host, such as * Suspend-to-RAM, Suspend-to-Disk, or Hybrid-Suspend, so that a request * to suspend/hibernate the host can be handled appropriately based on * this information. * * Returns 0 if successful, and -1 in case of error. */ int virNodeSuspendInit(void) { if (virMutexInit(&virNodeSuspendMutex) < 0) return -1; /* Get the power management capabilities supported by the host */ hostPMFeatures = 0; if (virGetPMCapabilities(&hostPMFeatures) < 0) { if (geteuid() == 0) VIR_ERROR(_("Failed to get host power management features")); } return 0; } /** * virNodeSuspendSetNodeWakeup: * @alarmTime: time in seconds from now, at which the RTC alarm has to be set. * * Set up the RTC alarm to the specified time. * Return 0 on success, -1 on failure. */ static int virNodeSuspendSetNodeWakeup(unsigned long long alarmTime) { virCommandPtr setAlarmCmd; int ret = -1; if (alarmTime <= MIN_TIME_REQ_FOR_SUSPEND) { virNodeSuspendError(VIR_ERR_INVALID_ARG, "%s", _("Suspend duration is too short")); return -1; } setAlarmCmd = virCommandNewArgList("rtcwake", "-m", "no", "-s", NULL); virCommandAddArgFormat(setAlarmCmd, "%lld", alarmTime); if (virCommandRun(setAlarmCmd, NULL) < 0) goto cleanup; ret = 0; cleanup: virCommandFree(setAlarmCmd); return ret; } /** * virNodeSuspend: * @cmdString: pointer to the command string this thread has to execute. * * Actually perform the suspend operation by invoking the command. * Give a short delay before executing the command so as to give a chance * to virNodeSuspendForDuration() to return the status to the caller. * If we don't give this delay, that function will not be able to return * the status, since the suspend operation would have begun and hence no * data can be sent through the connection to the caller. However, with * this delay added, the status return is best-effort only. */ static void virNodeSuspend(void *cmdString) { virCommandPtr suspendCmd = virCommandNew((char *)cmdString); VIR_FREE(cmdString); /* * Delay for sometime so that the function nodeSuspendForDuration() * can return the status to the caller. */ sleep(SUSPEND_DELAY); if (virCommandRun(suspendCmd, NULL) < 0) VIR_WARN("Failed to suspend the host"); virCommandFree(suspendCmd); /* * Now that we have resumed from suspend or the suspend failed, * reset 'aboutToSuspend' flag. */ virNodeSuspendLock(); aboutToSuspend = false; virNodeSuspendUnlock(); } /** * nodeSuspendForDuration: * @conn: pointer to the hypervisor connection * @target: the state to which the host must be suspended to - * VIR_NODE_SUSPEND_TARGET_MEM (Suspend-to-RAM), * VIR_NODE_SUSPEND_TARGET_DISK (Suspend-to-Disk), * VIR_NODE_SUSPEND_TARGET_HYBRID (Hybrid-Suspend) * @duration: the time duration in seconds, for which the host must be * suspended * @flags: any flag values that might need to be passed; currently unused. * * Suspend the node (host machine) for the given duration of time in the * specified state (such as Mem, Disk or Hybrid-Suspend). Attempt to resume * the node after the time duration is complete. * * First, an RTC alarm is set appropriately to wake up the node from its * sleep state. Then the actual node suspend operation is carried out * asynchronously in another thread, after a short time delay so as to * give enough time for this function to return status to its caller * through the connection. However this returning of status is best-effort * only, and should generally happen due to the short delay but might be * missed if the machine suspends first. * * Returns 0 in case the node is going to be suspended after a short delay, * -1 if suspending the node is not supported, or if a previous suspend * operation is still in progress. */ int nodeSuspendForDuration(virConnectPtr conn ATTRIBUTE_UNUSED, unsigned int target, unsigned long long duration, unsigned int flags) { static virThread thread; char *cmdString = NULL; virCheckFlags(0, -1); /* * Ensure that we are the only ones trying to suspend. * Fail if somebody has already initiated a suspend. */ virNodeSuspendLock(); if (aboutToSuspend) { /* A suspend operation is already in progress */ virNodeSuspendUnlock(); return -1; } else { aboutToSuspend = true; } virNodeSuspendUnlock(); /* Check if the host supports the requested suspend target */ switch (target) { case VIR_NODE_SUSPEND_TARGET_MEM: if (hostPMFeatures & (1 << VIR_NODE_SUSPEND_TARGET_MEM)) { cmdString = strdup("pm-suspend"); if (cmdString == NULL) { virReportOOMError(); goto cleanup; } break; } virNodeSuspendError(VIR_ERR_ARGUMENT_UNSUPPORTED, "%s", _("Suspend-to-RAM")); goto cleanup; case VIR_NODE_SUSPEND_TARGET_DISK: if (hostPMFeatures & (1 << VIR_NODE_SUSPEND_TARGET_DISK)) { cmdString = strdup("pm-hibernate"); if (cmdString == NULL) { virReportOOMError(); goto cleanup; } break; } virNodeSuspendError(VIR_ERR_ARGUMENT_UNSUPPORTED, "%s", _("Suspend-to-Disk")); goto cleanup; case VIR_NODE_SUSPEND_TARGET_HYBRID: if (hostPMFeatures & (1 << VIR_NODE_SUSPEND_TARGET_HYBRID)) { cmdString = strdup("pm-suspend-hybrid"); if (cmdString == NULL) { virReportOOMError(); goto cleanup; } break; } virNodeSuspendError(VIR_ERR_ARGUMENT_UNSUPPORTED, "%s", _("Hybrid-Suspend")); goto cleanup; default: virNodeSuspendError(VIR_ERR_INVALID_ARG, "%s", _("Invalid suspend target")); goto cleanup; } /* Just set the RTC alarm. Don't suspend yet. */ if (virNodeSuspendSetNodeWakeup(duration) < 0) goto cleanup; if (virThreadCreate(&thread, false, virNodeSuspend, (void *)cmdString) < 0) { virNodeSuspendError(VIR_ERR_INTERNAL_ERROR, "%s", _("Failed to create thread to suspend the host\n")); goto cleanup; } return 0; cleanup: VIR_FREE(cmdString); return -1; }