Re: [libvirt] [PATCH 4/4] Add domainSave/Restore to libxl driver

--- src/libxl/libxl_conf.h | 10 +++ src/libxl/libxl_driver.c | 184 +++++++++++++++++++++++++++++++++++++++++++++- 2 files changed, 191 insertions(+), 3 deletions(-) diff --git a/src/libxl/libxl_conf.h b/src/libxl/libxl_conf.h index f2f0d8a..e28615b 100644 --- a/src/libxl/libxl_conf.h +++ b/src/libxl/libxl_conf.h @@ -1,5 +1,6 @@ /*---------------------------------------------------------------------------*/ /* Copyright (c) 2011 SUSE LINUX Products GmbH, Nuernberg, Germany. + * Copyright (C) 2011 Univention GmbH. * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public @@ -17,6 +18,7 @@ * * Authors: * Jim Fehlig <jfehlig(a)novell.com&gt; + * Markus Groß <gross(a)univention.de&gt; */ /*---------------------------------------------------------------------------*/ @@ -85,6 +87,14 @@ struct _libxlDomainObjPrivate { int eventHdl; }; +static const char libxlSavefileMagic[16]= "libvirt-xml\n \0 \r"; +typedef struct _libxlSavefileHeader libxlSavefileHeader; +typedef libxlSavefileHeader *libxlSavefileHeaderPtr; +struct _libxlSavefileHeader { + char magic[16]; /* magic id */ + uint32_t xmlLen; /* length of saved xml */ +};

+ # define libxlError(code, ...) \ virReportErrorHelper(NULL, VIR_FROM_LIBXL, code, __FILE__, \ diff --git a/src/libxl/libxl_driver.c b/src/libxl/libxl_driver.c index 1539385..b02d4b7 100644 --- a/src/libxl/libxl_driver.c +++ b/src/libxl/libxl_driver.c @@ -29,6 +29,7 @@ #include <sys/utsname.h> #include <math.h> #include <libxl.h> +#include <fcntl.h> #include "internal.h" #include "logging.h" @@ -60,7 +61,6 @@ static libxlDriverPrivatePtr libxl_driver = NULL; - /* Function declarations */ static int libxlVmStart(libxlDriverPrivatePtr driver, @@ -1555,6 +1555,184 @@ libxlDomainGetInfo(virDomainPtr dom, virDomainInfoPtr info) } static int +libxlDomainSave(virDomainPtr dom, const char * to) +{ + libxlDriverPrivatePtr driver = dom->conn->privateData; + virDomainObjPtr vm; + libxlDomainObjPrivatePtr priv; + virDomainEventPtr event = NULL; + libxlSavefileHeader hdr; + libxl_domain_suspend_info s_info; + char * xml; + uint32_t xml_len; + 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 (vm->state != VIR_DOMAIN_PAUSED) { + memset(&s_info, 0, sizeof(s_info)); + + if ((fd = virFileOpenAs(to, O_CREAT|O_TRUNC|O_WRONLY, S_IRUSR|S_IWUSR, + getuid(), getgid(), 0)) < 0) { + virReportSystemError(-fd, + _("Failed to create domain save file '%s'"), + to); + goto cleanup; + } + + if ((xml = virDomainDefFormat(vm->def, 0)) == NULL) + goto cleanup; + xml_len = strlen(xml) + 1; + + memset(&hdr, 0, sizeof(hdr)); + memcpy(hdr.magic, libxlSavefileMagic, sizeof(hdr.magic)); + hdr.xmlLen = xml_len; + + if (safewrite(fd, &hdr, sizeof(hdr)) != sizeof(hdr)) { + libxlError(VIR_ERR_OPERATION_FAILED, + _("Failed to write save file header")); + goto cleanup; + } + + if (safewrite(fd, xml, xml_len) != xml_len) { + libxlError(VIR_ERR_OPERATION_FAILED, + _("Failed to write xml description")); + goto cleanup; + } + + if (libxl_domain_suspend(&priv->ctx, &s_info, dom->id, fd) != 0) { + libxlError(VIR_ERR_INTERNAL_ERROR, + _("Failed to save domain '%d' with libxenlight"), + dom->id); + goto cleanup; + } + + event = virDomainEventNewFromObj(vm, VIR_DOMAIN_EVENT_STOPPED, + VIR_DOMAIN_EVENT_STOPPED_SAVED); + + if (libxlVmReap(driver, vm, 1) != 0) { + libxlError(VIR_ERR_INTERNAL_ERROR, + _("Failed to destroy domain '%d'"), dom->id); + goto cleanup; + } + + if (!vm->persistent) { + virDomainRemoveInactive(&driver->domains, vm); + vm = NULL; + } + ret = 0; + } +cleanup: + VIR_FREE(xml); + if (VIR_CLOSE(fd) < 0) + virReportSystemError(errno, "%s", _("cannot close file")); + if (vm) + virDomainObjUnlock(vm); + if (event) + libxlDomainEventQueue(driver, event); + libxlDriverUnlock(driver); + return ret; +} + +static int +libxlDomainRestore(virConnectPtr conn, const char * from) +{ + libxlDriverPrivatePtr driver = conn->privateData; + virDomainDefPtr def = NULL; + virDomainObjPtr vm = NULL; + virDomainEventPtr event = NULL; + libxlSavefileHeader hdr; + char * xml = NULL; + int fd; + 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, libxlSavefileMagic, sizeof(hdr.magic))) { + libxlError(VIR_ERR_INVALID_ARG, "%s", _("image magic is incorrect")); + 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, 0))) + goto cleanup; + + if (virDomainObjIsDuplicate(&driver->domains, def, 1) < 0) + goto cleanup; + + if (!(vm = virDomainAssignDef(driver->caps, &driver->domains, def, false))) + goto cleanup; + + def = NULL; + + ret = libxlVmStart(driver, vm, false);

+ + if (ret == 0) { + event = virDomainEventNewFromObj(vm, VIR_DOMAIN_EVENT_STARTED, + VIR_DOMAIN_EVENT_STARTED_RESTORED); + } else if (ret < 0 && !vm->persistent) { + virDomainRemoveInactive(&driver->domains, vm); + vm = NULL; + } + +cleanup: + VIR_FREE(xml); + virDomainDefFree(def); + if (VIR_CLOSE(fd) < 0) + virReportSystemError(errno, "%s", _("cannot close file")); + if (vm) + virDomainObjUnlock(vm); + if (event) + libxlDomainEventQueue(driver, event); + libxlDriverUnlock(driver); + return ret; +} + +static int libxlDomainSetVcpusFlags(virDomainPtr dom, unsigned int nvcpus, unsigned int flags) { @@ -2658,8 +2836,8 @@ static virDriver libxlDriver = { NULL, /* domainSetBlkioParameters */ NULL, /* domainGetBlkioParameters */ libxlDomainGetInfo, /* domainGetInfo */ - NULL, /* domainSave */ - NULL, /* domainRestore */ + libxlDomainSave, /* domainSave */ + libxlDomainRestore, /* domainRestore */ NULL, /* domainCoreDump */ libxlDomainSetVcpus, /* domainSetVcpus */ libxlDomainSetVcpusFlags, /* domainSetVcpusFlags */