On Thu, Sep 24, 2020 at 01:43:56PM +0200, Peter Krempa wrote:
> From: Masayoshi Mizuma <m.mizuma@xxxxxxxxxxxxxx>
>
> 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@xxxxxxxxxxxxxx>
> Signed-off-by: Peter Krempa <pkrempa@xxxxxxxxxx>
> ---
> 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,
> --
Tested-by: Masayoshi Mizuma <m.mizuma@xxxxxxxxxxxxxx>
Thanks a lot!
Masa
