Re: [PATCH v4 09/11] qemu: validate: Allow <transient/> disks

From: Masayoshi Mizuma <m.mizuma(a)jp.fujitsu.com&gt; Extract the validation of transient disk option. We support transient disks in qemu under the following conditions: - -blockdev is used - the disk source is a local file - the disk type is 'disk' - the disk is not readonly Signed-off-by: Masayoshi Mizuma <m.mizuma(a)jp.fujitsu.com&gt; Signed-off-by: Peter Krempa <pkrempa(a)redhat.com&gt; --- docs/formatdomain.rst | 5 ++-- src/qemu/qemu_validate.c | 56 +++++++++++++++++++++++++++++++++++----- 2 files changed, 53 insertions(+), 8 deletions(-) diff --git a/docs/formatdomain.rst b/docs/formatdomain.rst index 888db5ea29..cc1467c0e6 100644 --- a/docs/formatdomain.rst +++ b/docs/formatdomain.rst @@ -2974,8 +2974,9 @@ paravirtualized driver is specified via the ``disk`` element. ``transient`` If present, this indicates that changes to the device contents should be reverted automatically when the guest exits. With some hypervisors, marking a - disk transient prevents the domain from participating in migration or - snapshots. Only suppported in vmx hypervisor. :since:`Since 0.9.5` + disk transient prevents the domain from participating in migration, + snapshots, or blockjobs. Only suppported in vmx hypervisor + (:since:`Since 0.9.5`) and ``qemu`` hypervisor (:since:`Since 6.9.0`). ``serial`` If present, this specify serial number of virtual hard drive. For example, it may look like ``<serial>WD-WMAP9A966149</serial>``. Not supported for diff --git a/src/qemu/qemu_validate.c b/src/qemu/qemu_validate.c index 3ed4039cdf..3196814aca 100644 --- a/src/qemu/qemu_validate.c +++ b/src/qemu/qemu_validate.c @@ -2186,12 +2186,6 @@ qemuValidateDomainDeviceDefDiskFrontend(const virDomainDiskDef *disk, } } - if (disk->transient) { - virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s", - _("transient disks not supported yet")); - return -1; - } - if (disk->iomode == VIR_DOMAIN_DISK_IO_NATIVE && disk->cachemode != VIR_DOMAIN_DISK_CACHE_DIRECTSYNC && disk->cachemode != VIR_DOMAIN_DISK_CACHE_DISABLE) { @@ -2340,6 +2334,53 @@ qemuValidateDomainDeviceDefDiskBlkdeviotune(const virDomainDiskDef *disk, } +static int +qemuValidateDomainDeviceDefDiskTransient(const virDomainDiskDef *disk, + virQEMUCapsPtr qemuCaps) + +{ + virStorageType actualType = virStorageSourceGetActualType(disk->src); + + if (!disk->transient) + return 0; + + if (virStorageSourceIsEmpty(disk->src)) { + virReportError(VIR_ERR_CONFIG_UNSUPPORTED, + _("transient disk '%s' must not be empty"), disk->dst); + return -1; + } + + if (disk->src->readonly) { + virReportError(VIR_ERR_CONFIG_UNSUPPORTED, + _("transient disk '%s' must not be read-only"), disk->dst); + return -1; + } + + if (actualType != VIR_STORAGE_TYPE_FILE) { + virReportError(VIR_ERR_CONFIG_UNSUPPORTED, + _("transient disk supported only with 'file' type (%s)"), + disk->dst); + return -1; + } + + if (disk->device != VIR_DOMAIN_DISK_DEVICE_DISK) { + virReportError(VIR_ERR_CONFIG_UNSUPPORTED, + _("transient disk supported only with 'disk' device (%s)"), + disk->dst); + return -1; + } + + if (qemuCaps && !virQEMUCapsGet(qemuCaps, QEMU_CAPS_BLOCKDEV)) { + virReportError(VIR_ERR_CONFIG_UNSUPPORTED, + _("transient disk not supported by this qemu binary (%s)"), + disk->dst); + return -1; + } + + return 0; +} + + int qemuValidateDomainDeviceDefDisk(const virDomainDiskDef *disk, const virDomainDef *def, @@ -2357,6 +2398,9 @@ qemuValidateDomainDeviceDefDisk(const virDomainDiskDef *disk, if (qemuValidateDomainDeviceDefDiskBlkdeviotune(disk, def, qemuCaps) < 0) return -1; + if (qemuValidateDomainDeviceDefDiskTransient(disk, qemuCaps) < 0) + return -1; + if (disk->src->shared && !disk->src->readonly && !qemuBlockStorageSourceSupportsConcurrentAccess(disk->src)) { virReportError(VIR_ERR_CONFIG_UNSUPPORTED, --