From 5b6c961ef29eee896df8603c5070a630b761b17f Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Markus=20Gro=C3=9F?= Date: Thu, 2 Jun 2011 20:24:30 +0800 Subject: [PATCH] libxl: adds managed save and restore support Based on the equivalent qemu driver code * src/libxl/libxl_driver.c: refactor the Start save and restore routines of the driver and adds the new entry points for managed saves handling --- src/libxl/libxl_driver.c | 363 ++++++++++++++++++++++++++++++--------- 1 file changed, 281 insertions(+), 82 deletions(-) diff --git a/src/libxl/libxl_driver.c b/src/libxl/libxl_driver.c index 61c3494bc4..9bcc3b9f51 100644 --- a/src/libxl/libxl_driver.c +++ b/src/libxl/libxl_driver.c @@ -66,7 +66,6 @@ static int libxlVmStart(libxlDriverPrivatePtr driver, virDomainObjPtr vm, bool start_paused, int restore_fd); - /* Function definitions */ static void libxlDriverLock(libxlDriverPrivatePtr driver) @@ -219,6 +218,87 @@ libxlDoNodeGetInfo(libxlDriverPrivatePtr driver, virNodeInfoPtr info) return 0; } +static char * +libxlDomainManagedSavePath(libxlDriverPrivatePtr driver, virDomainObjPtr vm) { + char *ret; + + if (virAsprintf(&ret, "%s/%s.save", driver->saveDir, vm->def->name) < 0) { + virReportOOMError(); + return NULL; + } + + return ret; +} + +/* This internal function expects the driver lock to already be held on + * entry. */ +static int ATTRIBUTE_NONNULL(3) ATTRIBUTE_NONNULL(4) +libxlSaveImageOpen(libxlDriverPrivatePtr driver, const char *from, + virDomainDefPtr *ret_def, libxlSavefileHeaderPtr ret_hdr) +{ + int fd; + virDomainDefPtr def = NULL; + libxlSavefileHeader hdr; + char *xml = NULL; + + if ((fd = virFileOpenAs(from, O_RDONLY, 0, getuid(), getgid(), 0)) < 0) { + libxlError(VIR_ERR_OPERATION_FAILED, + "%s", _("cannot read domain image")); + goto error; + } + + if (saferead(fd, &hdr, sizeof(hdr)) != sizeof(hdr)) { + libxlError(VIR_ERR_OPERATION_FAILED, + "%s", _("failed to read libxl header")); + goto error; + } + + if (memcmp(hdr.magic, LIBXL_SAVE_MAGIC, sizeof(hdr.magic))) { + libxlError(VIR_ERR_INVALID_ARG, "%s", _("image magic is incorrect")); + goto error; + } + + if (hdr.version > LIBXL_SAVE_VERSION) { + libxlError(VIR_ERR_OPERATION_FAILED, + _("image version is not supported (%d > %d)"), + hdr.version, LIBXL_SAVE_VERSION); + goto error; + } + + if (hdr.xmlLen <= 0) { + libxlError(VIR_ERR_OPERATION_FAILED, + _("invalid XML length: %d"), hdr.xmlLen); + goto error; + } + + if (VIR_ALLOC_N(xml, hdr.xmlLen) < 0) { + virReportOOMError(); + goto error; + } + + if (saferead(fd, xml, hdr.xmlLen) != hdr.xmlLen) { + libxlError(VIR_ERR_OPERATION_FAILED, "%s", _("failed to read XML")); + goto error; + } + + if (!(def = virDomainDefParseString(driver->caps, xml, + VIR_DOMAIN_XML_INACTIVE))) + goto error; + + VIR_FREE(xml); + + *ret_def = def; + *ret_hdr = hdr; + + return fd; + +error: + VIR_FREE(xml); + virDomainDefFree(def); + VIR_FORCE_CLOSE(fd); + return -1; +} + /* * Cleanup function for domain that has reached shutoff state. * @@ -546,17 +626,53 @@ libxlVmStart(libxlDriverPrivatePtr driver, virDomainObjPtr vm, bool start_paused, int restore_fd) { libxl_domain_config d_config; - virDomainDefPtr def = vm->def; + virDomainDefPtr def = NULL; virDomainEventPtr event = NULL; + libxlSavefileHeader hdr; int ret; uint32_t domid = 0; char *dom_xml = NULL; + char *managed_save = NULL; pid_t child_console_pid = -1; libxlDomainObjPrivatePtr priv = vm->privateData; + /* If there is a managed saved state restore it instead of starting + * from scratch. The old state is removed once the restoring succeeded. */ + if (restore_fd < 0) { + managed_save = libxlDomainManagedSavePath(driver, vm); + if (managed_save == NULL) + goto error; + + if (virFileExists(managed_save)) { + + restore_fd = libxlSaveImageOpen(driver, managed_save, &def, &hdr); + if (restore_fd < 0) + goto error; + + if (STRNEQ(vm->def->name, def->name) || + memcmp(vm->def->uuid, def->uuid, VIR_UUID_BUFLEN)) { + char vm_uuidstr[VIR_UUID_STRING_BUFLEN]; + char def_uuidstr[VIR_UUID_STRING_BUFLEN]; + virUUIDFormat(vm->def->uuid, vm_uuidstr); + virUUIDFormat(def->uuid, def_uuidstr); + libxlError(VIR_ERR_OPERATION_FAILED, + _("cannot restore domain '%s' uuid %s from a file" + " which belongs to domain '%s' uuid %s"), + vm->def->name, vm_uuidstr, def->name, def_uuidstr); + goto error; + } + + virDomainObjAssignDef(vm, def, true); + def = NULL; + + if (unlink(managed_save) < 0) + VIR_WARN("Failed to remove the managed state %s", managed_save); + } + } + memset(&d_config, 0, sizeof(d_config)); - if (libxlBuildDomainConfig(driver, def, &d_config) < 0 ) + if (libxlBuildDomainConfig(driver, vm->def, &d_config) < 0 ) return -1; if (libxlFreeMem(priv, &d_config) < 0) { @@ -586,8 +702,8 @@ libxlVmStart(libxlDriverPrivatePtr driver, virDomainObjPtr vm, goto error; } - def->id = domid; - if ((dom_xml = virDomainDefFormat(def, 0)) == NULL) + vm->def->id = domid; + if ((dom_xml = virDomainDefFormat(vm->def, 0)) == NULL) goto error; if (libxl_userdata_store(&priv->ctx, domid, "libvirt-xml", @@ -627,11 +743,14 @@ libxlVmStart(libxlDriverPrivatePtr driver, virDomainObjPtr vm, error: if (domid > 0) { libxl_domain_destroy(&priv->ctx, domid, 0); - def->id = -1; + vm->def->id = -1; virDomainObjSetState(vm, VIR_DOMAIN_SHUTOFF, VIR_DOMAIN_SHUTOFF_FAILED); } libxl_domain_config_destroy(&d_config); VIR_FREE(dom_xml); + VIR_FREE(managed_save); + virDomainDefFree(def); + VIR_FORCE_CLOSE(restore_fd); return -1; } @@ -1692,12 +1811,13 @@ libxlDomainGetState(virDomainPtr dom, return ret; } +/* This internal function expects the driver lock to already be held on + * entry and the vm must be active. */ static int -libxlDomainSave(virDomainPtr dom, const char *to) +libxlDoDomainSave(libxlDriverPrivatePtr driver, virDomainObjPtr vm, + const char *to) { - libxlDriverPrivatePtr driver = dom->conn->privateData; - virDomainObjPtr vm; - libxlDomainObjPrivatePtr priv; + libxlDomainObjPrivatePtr priv = vm->privateData; libxlSavefileHeader hdr; virDomainEventPtr event = NULL; char *xml = NULL; @@ -1705,28 +1825,10 @@ libxlDomainSave(virDomainPtr dom, const char *to) int fd; int ret = -1; - libxlDriverLock(driver); - vm = virDomainFindByUUID(&driver->domains, dom->uuid); - - if (!vm) { - char uuidstr[VIR_UUID_STRING_BUFLEN]; - virUUIDFormat(dom->uuid, uuidstr); - libxlError(VIR_ERR_NO_DOMAIN, - _("No domain with matching uuid '%s'"), uuidstr); - goto cleanup; - } - - if (!virDomainObjIsActive(vm)) { - libxlError(VIR_ERR_OPERATION_INVALID, "%s", _("Domain is not running")); - goto cleanup; - } - - priv = vm->privateData; - if (virDomainObjGetState(vm, NULL) == VIR_DOMAIN_PAUSED) { libxlError(VIR_ERR_OPERATION_INVALID, _("Domain '%d' has to be running because libxenlight will" - " suspend it"), dom->id); + " suspend it"), vm->def->id); goto cleanup; } @@ -1758,10 +1860,10 @@ libxlDomainSave(virDomainPtr dom, const char *to) goto cleanup; } - if (libxl_domain_suspend(&priv->ctx, NULL, dom->id, fd) != 0) { + if (libxl_domain_suspend(&priv->ctx, NULL, vm->def->id, fd) != 0) { libxlError(VIR_ERR_INTERNAL_ERROR, _("Failed to save domain '%d' with libxenlight"), - dom->id); + vm->def->id); goto cleanup; } @@ -1770,7 +1872,7 @@ libxlDomainSave(virDomainPtr dom, const char *to) if (libxlVmReap(driver, vm, 1, VIR_DOMAIN_SHUTOFF_SAVED) != 0) { libxlError(VIR_ERR_INTERNAL_ERROR, - _("Failed to destroy domain '%d'"), dom->id); + _("Failed to destroy domain '%d'"), vm->def->id); goto cleanup; } @@ -1785,10 +1887,39 @@ cleanup: VIR_FREE(xml); if (VIR_CLOSE(fd) < 0) virReportSystemError(errno, "%s", _("cannot close file")); - if (vm) - virDomainObjUnlock(vm); if (event) libxlDomainEventQueue(driver, event); + return ret; +} + +static int +libxlDomainSave(virDomainPtr dom, const char *to) +{ + libxlDriverPrivatePtr driver = dom->conn->privateData; + virDomainObjPtr vm; + int ret = -1; + + libxlDriverLock(driver); + vm = virDomainFindByUUID(&driver->domains, dom->uuid); + + if (!vm) { + char uuidstr[VIR_UUID_STRING_BUFLEN]; + virUUIDFormat(dom->uuid, uuidstr); + libxlError(VIR_ERR_NO_DOMAIN, + _("No domain with matching uuid '%s'"), uuidstr); + goto cleanup; + } + + if (!virDomainObjIsActive(vm)) { + libxlError(VIR_ERR_OPERATION_INVALID, "%s", _("Domain is not running")); + goto cleanup; + } + + ret = libxlDoDomainSave(driver, vm, to); + +cleanup: + if (vm) + virDomainObjUnlock(vm); libxlDriverUnlock(driver); return ret; } @@ -1797,57 +1928,16 @@ static int libxlDomainRestore(virConnectPtr conn, const char *from) { libxlDriverPrivatePtr driver = conn->privateData; - virDomainDefPtr def = NULL; virDomainObjPtr vm = NULL; + virDomainDefPtr def = NULL; libxlSavefileHeader hdr; - char *xml = NULL; - int fd; + int fd = -1; int ret = -1; libxlDriverLock(driver); - if ((fd = virFileOpenAs(from, O_RDONLY, 0, getuid(), getgid(), 0)) < 0) { - libxlError(VIR_ERR_OPERATION_FAILED, - "%s", _("cannot read domain image")); - goto cleanup; - } - - if (saferead(fd, &hdr, sizeof(hdr)) != sizeof(hdr)) { - libxlError(VIR_ERR_OPERATION_FAILED, - "%s", _("failed to read libxl header")); - goto cleanup; - } - - if (memcmp(hdr.magic, LIBXL_SAVE_MAGIC, sizeof(hdr.magic))) { - libxlError(VIR_ERR_INVALID_ARG, "%s", _("image magic is incorrect")); - goto cleanup; - } - - if (hdr.version > LIBXL_SAVE_VERSION) { - libxlError(VIR_ERR_OPERATION_FAILED, - _("image version is not supported (%d > %d)"), - hdr.version, LIBXL_SAVE_VERSION); - goto cleanup; - } - - if (hdr.xmlLen <= 0) { - libxlError(VIR_ERR_OPERATION_FAILED, - _("invalid XML length: %d"), hdr.xmlLen); - goto cleanup; - } - - if (VIR_ALLOC_N(xml, hdr.xmlLen) < 0) { - virReportOOMError(); - goto cleanup; - } - - if (saferead(fd, xml, hdr.xmlLen) != hdr.xmlLen) { - libxlError(VIR_ERR_OPERATION_FAILED, "%s", _("failed to read XML")); - goto cleanup; - } - - if (!(def = virDomainDefParseString(driver->caps, xml, - VIR_DOMAIN_XML_INACTIVE))) + fd = libxlSaveImageOpen(driver, from, &def, &hdr); + if (fd < 0) goto cleanup; if (virDomainObjIsDuplicate(&driver->domains, def, 1) < 0) @@ -1865,10 +1955,7 @@ libxlDomainRestore(virConnectPtr conn, const char *from) } cleanup: - VIR_FREE(xml); virDomainDefFree(def); - if (VIR_CLOSE(fd) < 0) - virReportSystemError(errno, "%s", _("cannot close file")); if (vm) virDomainObjUnlock(vm); libxlDriverUnlock(driver); @@ -1969,6 +2056,115 @@ cleanup: return ret; } +static int +libxlDomainManagedSave(virDomainPtr dom, unsigned int flags) +{ + libxlDriverPrivatePtr driver = dom->conn->privateData; + virDomainObjPtr vm = NULL; + char *name = NULL; + int ret = -1; + + virCheckFlags(0, -1); + + libxlDriverLock(driver); + vm = virDomainFindByUUID(&driver->domains, dom->uuid); + if (!vm) { + char uuidstr[VIR_UUID_STRING_BUFLEN]; + virUUIDFormat(dom->uuid, uuidstr); + libxlError(VIR_ERR_NO_DOMAIN, + _("No domain with matching uuid '%s'"), uuidstr); + goto cleanup; + } + + if (!virDomainObjIsActive(vm)) { + libxlError(VIR_ERR_OPERATION_INVALID, "%s", _("Domain is not running")); + goto cleanup; + } + + name = libxlDomainManagedSavePath(driver, vm); + if (name == NULL) + goto cleanup; + + VIR_INFO("Saving state to %s", name); + + ret = libxlDoDomainSave(driver, vm, name); + +cleanup: + if (vm) + virDomainObjUnlock(vm); + libxlDriverUnlock(driver); + VIR_FREE(name); + return ret; +} + +static int +libxlDomainHasManagedSaveImage(virDomainPtr dom, unsigned int flags) +{ + libxlDriverPrivatePtr driver = dom->conn->privateData; + virDomainObjPtr vm = NULL; + int ret = -1; + char *name = NULL; + + virCheckFlags(0, -1); + + libxlDriverLock(driver); + vm = virDomainFindByUUID(&driver->domains, dom->uuid); + if (!vm) { + char uuidstr[VIR_UUID_STRING_BUFLEN]; + virUUIDFormat(dom->uuid, uuidstr); + libxlError(VIR_ERR_NO_DOMAIN, + _("No domain with matching uuid '%s'"), uuidstr); + goto cleanup; + } + + name = libxlDomainManagedSavePath(driver, vm); + if (name == NULL) + goto cleanup; + + ret = virFileExists(name); + +cleanup: + VIR_FREE(name); + if (vm) + virDomainObjUnlock(vm); + libxlDriverUnlock(driver); + return ret; +} + +static int +libxlDomainManagedSaveRemove(virDomainPtr dom, unsigned int flags) +{ + libxlDriverPrivatePtr driver = dom->conn->privateData; + virDomainObjPtr vm = NULL; + int ret = -1; + char *name = NULL; + + virCheckFlags(0, -1); + + libxlDriverLock(driver); + vm = virDomainFindByUUID(&driver->domains, dom->uuid); + if (!vm) { + char uuidstr[VIR_UUID_STRING_BUFLEN]; + virUUIDFormat(dom->uuid, uuidstr); + libxlError(VIR_ERR_NO_DOMAIN, + _("No domain with matching uuid '%s'"), uuidstr); + goto cleanup; + } + + name = libxlDomainManagedSavePath(driver, vm); + if (name == NULL) + goto cleanup; + + ret = unlink(name); + +cleanup: + VIR_FREE(name); + if (vm) + virDomainObjUnlock(vm); + libxlDriverUnlock(driver); + return ret; +} + static int libxlDomainSetVcpusFlags(virDomainPtr dom, unsigned int nvcpus, unsigned int flags) @@ -3634,6 +3830,9 @@ static virDriver libxlDriver = { .nodeGetFreeMemory = libxlNodeGetFreeMemory, /* 0.9.0 */ .domainEventRegister = libxlDomainEventRegister, /* 0.9.0 */ .domainEventDeregister = libxlDomainEventDeregister, /* 0.9.0 */ + .domainManagedSave = libxlDomainManagedSave, /* 0.9.3 */ + .domainHasManagedSaveImage = libxlDomainHasManagedSaveImage, /* 0.9.3 */ + .domainManagedSaveRemove = libxlDomainManagedSaveRemove, /* 0.9.3 */ .domainIsActive = libxlDomainIsActive, /* 0.9.0 */ .domainIsPersistent = libxlDomainIsPersistent, /* 0.9.0 */ .domainIsUpdated = libxlDomainIsUpdated, /* 0.9.0 */