Re: [libvirt] [PATCH 12/13] Add support for an explicit IO error event

This introduces a new event type VIR_DOMAIN_EVENT_ID_IO_ERROR This event includes the action that is about to be taken as a result of the watchdog triggering typedef enum { VIR_DOMAIN_EVENT_IO_ERROR_NONE = 0, VIR_DOMAIN_EVENT_IO_ERROR_PAUSE, VIR_DOMAIN_EVENT_IO_ERROR_REPORT, } virDomainEventIOErrorAction;

In addition is has the source path of the disk that had the error and its unique device alias. It does not include the target device name (/dev/sda), since this would preclude triggering IO errors from other file backed devices (eg serial ports connected to a file) Thus there is a new callback definition for this event type typedef void (*virConnectDomainEventIOErrorCallback)(virConnectPtr conn, virDomainPtr dom, const char *srcPath, const char *devAlias, int action, void *opaque);

--- a/include/libvirt/libvirt.h.in +++ b/include/libvirt/libvirt.h.in @@ -1858,6 +1858,17 @@ typedef void (*virConnectDomainEventWatchdogCallback)(virConnectPtr conn, virDomainPtr dom, int action, void *opaque); +typedef enum { + VIR_DOMAIN_EVENT_IO_ERROR_NONE = 0, + VIR_DOMAIN_EVENT_IO_ERROR_PAUSE, + VIR_DOMAIN_EVENT_IO_ERROR_REPORT, +} virDomainEventIOErrorAction;

+typedef void (*virConnectDomainEventIOErrorCallback)(virConnectPtr conn, + virDomainPtr dom, + const char *srcPath, + const char *devAlias, + int action, + void *opaque); /* Use this to cast the event specific callback into the generic one * for use for virDomainEventRegister */ @@ -1869,6 +1880,7 @@ typedef enum { VIR_DOMAIN_EVENT_ID_REBOOT = 1, /* virConnectDomainEventGenericCallback */ VIR_DOMAIN_EVENT_ID_RTC_CHANGE = 2, /* virConnectDomainEventRTCChangeCallback */ VIR_DOMAIN_EVENT_ID_WATCHDOG = 3, /* virConnectDomainEventWatchdogCallback */ + VIR_DOMAIN_EVENT_ID_IO_ERROR = 4, /* virConnectDomainEventIOErrorCallback */ /* * NB: this enum value will increase over time as new events are

diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c index ceba5db..71cca5c 100644 --- a/src/qemu/qemu_driver.c +++ b/src/qemu/qemu_driver.c @@ -747,6 +747,26 @@ findDomainDiskByPath(virDomainObjPtr vm, return NULL; } +static virDomainDiskDefPtr +findDomainDiskByAlias(virDomainObjPtr vm, + const char *alias) +{ + int i; + + for (i = 0; i < vm->def->ndisks; i++) { + virDomainDiskDefPtr disk; + + disk = vm->def->disks[i]; + if (disk->info.alias != NULL && STREQ(disk->info.alias, alias)) + return disk; + } + + qemuReportError(VIR_ERR_INTERNAL_ERROR, + _("no disk found with alias %s"), + alias); + return NULL; +} + static int getVolumeQcowPassphrase(virConnectPtr conn, virDomainDiskDefPtr disk, @@ -928,12 +948,49 @@ qemuHandleDomainWatchdog(qemuMonitorPtr mon ATTRIBUTE_UNUSED, } +static int +qemuHandleDomainIOError(qemuMonitorPtr mon ATTRIBUTE_UNUSED, + virDomainObjPtr vm, + const char *diskAlias, + int action) +{ + struct qemud_driver *driver = qemu_driver; + virDomainEventPtr event; + const char *srcPath; + const char *devAlias; + virDomainDiskDefPtr disk; + + virDomainObjLock(vm); + disk = findDomainDiskByAlias(vm, diskAlias); + + if (disk) { + srcPath = disk->src; + devAlias = disk->info.alias; + } else { + srcPath = ""; + devAlias = ""; + } + + event = virDomainEventIOErrorNewFromObj(vm, srcPath, devAlias, action); + virDomainObjUnlock(vm); + + if (event) { + qemuDriverLock(driver); + qemuDomainEventQueue(driver, event); + qemuDriverUnlock(driver); + } + + return 0; +} + + static qemuMonitorCallbacks monitorCallbacks = { .eofNotify = qemuHandleMonitorEOF, .diskSecretLookup = findVolumeQcowPassphrase, .domainReset = qemuHandleDomainReset, .domainRTCChange = qemuHandleDomainRTCChange, .domainWatchdog = qemuHandleDomainWatchdog, + .domainIOError = qemuHandleDomainIOError, };