8:13 p.m.
On 12/05/2017 09:18 AM, Ján Tomko wrote:
On Mon, Dec 04, 2017 at 08:38:52PM -0500, John Ferlan wrote:
> In order to be able to reuse some code for both controller def
> validation and command line building, create a convenience helper
> that will perform the "skip" avoidance checks. It will also set
> some flags to allow the caller to specifically skip (or fail)
> depending on the result of the flag (as opposed to building up
> some ever growing list of variables).
>
> Signed-off-by: John Ferlan <jferlan(a)redhat.com>
> ---
> src/qemu/qemu_command.c | 61 +++++------------------------------
> src/qemu/qemu_domain.c | 84
> ++++++++++++++++++++++++++++++++++++++++++++++++-
> src/qemu/qemu_domain.h | 12 +++++++
> 3 files changed, 102 insertions(+), 55 deletions(-)
>
[...]
> diff --git a/src/qemu/qemu_domain.c b/src/qemu/qemu_domain.c
> index 569bbd29e..d4c7674c0 100644
> --- a/src/qemu/qemu_domain.c
> +++ b/src/qemu/qemu_domain.c
> @@ -3884,10 +3884,92 @@ qemuDomainDeviceDefValidateDisk(const
> virDomainDiskDef *disk)
> }
>
>
> +/**
> + * qemuDomainDeviceDefSkipController:
> + * @controller: Controller to check
> + * @def: Domain definition
> + * @flags: qemuDomainDeviceSkipFlags to set if specific condition found
> + *
> + * Returns true if this controller can be skipped for command line
> generation
> + * or device validation
We should not skip validation for implicit devices. Some of the checks
added later are for implicit devices (PCI root, SATA controller).
It would be enough to split out the logic of figuring out whether the
controller is implicit out of command line generation.
Obviously the "goal" was to avoid the same checks in Validation that
we're avoiding in command line building; however, if there are things
that need to be checked in Validation before what gets checked here,
then I could see that being "extra".
What I was trying to avoid was duplication of specific checks prior to
Validation that were being avoided anyways for command line building. As
in - we don't build that on the command line, so why bother checking
during validation.
> + */
> +bool
> +qemuDomainDeviceDefSkipController(const virDomainControllerDef
> *controller,
> + const virDomainDef *def,
> + unsigned int *flags)
> +{
> + /* skip USB controllers with type none.*/
> + if (controller->type == VIR_DOMAIN_CONTROLLER_TYPE_USB &&
> + controller->model == VIR_DOMAIN_CONTROLLER_MODEL_USB_NONE) {
> + *flags |= QEMU_DOMAIN_DEVICE_SKIP_USB_CONTROLLER_FLAG;
> + return true;
> + }
Simply returning true here (no USB controller is implicit) should
suffice. The caller can figure out whether USB_NONE is present
by going through the controllers array again (via virDomainDefHasUSB).
> +
> + /* skip pcie-root */
> + if (controller->type == VIR_DOMAIN_CONTROLLER_TYPE_PCI &&
> + controller->model == VIR_DOMAIN_CONTROLLER_MODEL_PCIE_ROOT)
> + return true;
> +
> + /* Skip pci-root, except for pSeries guests (which actually
> + * support more than one PCI Host Bridge per guest) */
> + if (!qemuDomainIsPSeries(def) &&
> + controller->type == VIR_DOMAIN_CONTROLLER_TYPE_PCI &&
> + controller->model == VIR_DOMAIN_CONTROLLER_MODEL_PCI_ROOT)
> + return true;
> +
> + /* first SATA controller on Q35 machines is implicit */
> + if (controller->type == VIR_DOMAIN_CONTROLLER_TYPE_SATA &&
> + controller->idx == 0 && qemuDomainIsQ35(def))
> + return true;
> +
> + /* first IDE controller is implicit on various machines */
> + if (controller->type == VIR_DOMAIN_CONTROLLER_TYPE_IDE &&
> + controller->idx == 0 && qemuDomainHasBuiltinIDE(def))
> + return true;
This one is the initial reason I figured it would be better to have a
Skip helper as opposed to "copying" the same check in the ValidateIDE
code that we'd have in the command line building code.
Then the subsequent ones made the ValidateUSB *so much* easier.
> +
> + if (controller->type == VIR_DOMAIN_CONTROLLER_TYPE_USB &&
> + controller->model == -1 &&
> + !qemuDomainIsQ35(def) &&
> + !qemuDomainIsVirt(def)) {
> +
> + /* An appropriate default USB controller model should already
> + * have been selected in qemuDomainDeviceDefPostParse(); if
> + * we still have no model by now, we have to fall back to the
> + * legacy USB controller.
> + *
> + * Note that we *don't* want to end up with the legacy USB
> + * controller for q35 and virt machines, so we go ahead and
> + * fail in qemuBuildControllerDevStr(); on the other hand,
> + * for s390 machines we want to ignore any USB controller
> + * (see 548ba43028 for the full story), so we skip
> + * qemuBuildControllerDevStr() but we don't ultimately end
> + * up adding the legacy USB controller */
> + if (*flags & QEMU_DOMAIN_DEVICE_SKIP_USB_LEGACY_FLAG) {
> + virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
> + _("Multiple legacy USB controllers are "
> + "not supported"));
A function returning bool where both options are valid should not be
setting errors.
Yeah - I figured this may cause a few eyebrows to raise.
For this error, validate can go through all the controllers. Command
line generator should not care and we can get rid of the remaining two
flags as their only purpose is to save us multiple passes through
the controllers field.
> + *flags |= QEMU_DOMAIN_DEVICE_SKIP_USB_LEGACY_FAIL_FLAG;
> + }
> + *flags |= QEMU_DOMAIN_DEVICE_SKIP_USB_LEGACY_FLAG;
> + return true;
> + }
> +
> + return false;
> +}
> +
> +
> static int
> qemuDomainDeviceDefValidateController(const virDomainControllerDef
> *controller,
> - const virDomainDef *def
> ATTRIBUTE_UNUSED)
> + const virDomainDef *def)
> {
> + unsigned int flags = 0;
> +
> + if (qemuDomainDeviceDefSkipController(controller, def, &flags))
> + return 0;
> +
> + if (flags & QEMU_DOMAIN_DEVICE_SKIP_USB_LEGACY_FAIL_FLAG)
> + return -1;
To possibly set this flag, SkipController must be called with non-zero
flags, so this would be dead code.
I'd rather go through def->controllers again to look for another legacy
controller, just for the purpose of validation.
OK - I'll try to figure out some sort of happy medium. It obviously
could affect subsequent patches in the series.
John
Jan
> +
> switch ((virDomainControllerType) controller->type) {
> case VIR_DOMAIN_CONTROLLER_TYPE_IDE:
> case VIR_DOMAIN_CONTROLLER_TYPE_FDC:
> diff --git a/src/qemu/qemu_domain.h b/src/qemu/qemu_domain.h
> index c33af3671..5c9c55d38 100644
> --- a/src/qemu/qemu_domain.h
> +++ b/src/qemu/qemu_domain.h
> @@ -999,4 +999,16 @@ qemuDomainPrepareDiskSource(virConnectPtr conn,
> qemuDomainObjPrivatePtr priv,
> virQEMUDriverConfigPtr cfg);
>
> +typedef enum {
> + QEMU_DOMAIN_DEVICE_SKIP_USB_CONTROLLER_FLAG = (1 << 0),
> + QEMU_DOMAIN_DEVICE_SKIP_USB_LEGACY_FLAG = (1 << 1),
> + QEMU_DOMAIN_DEVICE_SKIP_USB_LEGACY_FAIL_FLAG = (1 << 2),
> +} qemuDomainDeviceSkipFlags;
> +
> +bool
> +qemuDomainDeviceDefSkipController(const virDomainControllerDef
> *controller,
> + const virDomainDef *def,
> + unsigned int *flags);
> +
> +
> #endif /* __QEMU_DOMAIN_H__ */
> --
> 2.13.6
>
> --
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