[libvirt] [PATCH 2/3] qemu: Process the hostdev "rawio" setting

[Michal Privoznik]

On 10.09.2014 01:40, John Ferlan wrote:
> Mimic the "Disk" processing for 'rawio', but for a scsi_host hostdev
> lun device.
>
> Signed-off-by: John Ferlan <jferlan at redhat.com>
> ---
>   src/qemu/qemu_domain.c  | 21 +++++++++++++++++++++
>   src/qemu/qemu_domain.h  |  4 ++++
>   src/qemu/qemu_driver.c  |  1 +
>   src/qemu/qemu_process.c | 20 +++++++++++++++++++-
>   4 files changed, 45 insertions(+), 1 deletion(-)
>
> diff --git a/src/qemu/qemu_domain.c b/src/qemu/qemu_domain.c
> index 306ff10..166fadb 100644
> --- a/src/qemu/qemu_domain.c
> +++ b/src/qemu/qemu_domain.c
> @@ -1715,6 +1715,10 @@ void qemuDomainObjCheckTaint(virQEMUDriverPtr driver,
>       for (i = 0; i < obj->def->ndisks; i++)
>           qemuDomainObjCheckDiskTaint(driver, obj, obj->def->disks[i], logFD);
>
> +    for (i = 0; i < obj->def->nhostdevs; i++)
> +        qemuDomainObjCheckHostdevTaint(driver, obj, obj->def->hostdevs[i],
> +                                       logFD);
> +
>       for (i = 0; i < obj->def->nnets; i++)
>           qemuDomainObjCheckNetTaint(driver, obj, obj->def->nets[i], logFD);
>
> @@ -1741,6 +1745,23 @@ void qemuDomainObjCheckDiskTaint(virQEMUDriverPtr driver,
>   }
>
>
> +void qemuDomainObjCheckHostdevTaint(virQEMUDriverPtr driver,
> +                                    virDomainObjPtr obj,
> +                                    virDomainHostdevDefPtr hostdev,
> +                                    int logFD)
> +{
> +    virQEMUDriverConfigPtr cfg = virQEMUDriverGetConfig(driver);

This @cfg is not used anywhere in the function. Well, technically is - 
it's unref'd but besides that, it isn't. Is it a leftover from previous 
code of yours that you were testing?

> +    virDomainHostdevSubsysSCSIPtr scsisrc = &hostdev->source.subsys.u.scsi;
> +
> +    if (hostdev->source.subsys.type == VIR_DOMAIN_HOSTDEV_SUBSYS_TYPE_SCSI &&
> +        scsisrc->rawio == 1)

If you follow my advice from 1/3 then this would be 
s/1/VIR_TRISTATE_BOOL_YES/

> +            qemuDomainObjTaint(driver, obj, VIR_DOMAIN_TAINT_HIGH_PRIVILEGES,
> +                               logFD);
> +
> +    virObjectUnref(cfg);
> +}
> +
> +
>   void qemuDomainObjCheckNetTaint(virQEMUDriverPtr driver,
>                                   virDomainObjPtr obj,
>                                   virDomainNetDefPtr net,
> diff --git a/src/qemu/qemu_domain.h b/src/qemu/qemu_domain.h
> index f353d90..7aebb0f 100644
> --- a/src/qemu/qemu_domain.h
> +++ b/src/qemu/qemu_domain.h
> @@ -286,6 +286,10 @@ void qemuDomainObjCheckDiskTaint(virQEMUDriverPtr driver,
>                                    virDomainObjPtr obj,
>                                    virDomainDiskDefPtr disk,
>                                    int logFD);
> +void qemuDomainObjCheckHostdevTaint(virQEMUDriverPtr driver,
> +                                    virDomainObjPtr obj,
> +                                    virDomainHostdevDefPtr disk,
> +                                    int logFD);
>   void qemuDomainObjCheckNetTaint(virQEMUDriverPtr driver,
>                                   virDomainObjPtr obj,
>                                   virDomainNetDefPtr net,
> diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c
> index d724eeb..78ecb3e 100644
> --- a/src/qemu/qemu_driver.c
> +++ b/src/qemu/qemu_driver.c
> @@ -6548,6 +6548,7 @@ qemuDomainAttachDeviceLive(virDomainObjPtr vm,
>           break;
>
>       case VIR_DOMAIN_DEVICE_HOSTDEV:
> +        qemuDomainObjCheckHostdevTaint(driver, vm, dev->data.hostdev, -1);
>           ret = qemuDomainAttachHostDevice(dom->conn, driver, vm,
>                                            dev->data.hostdev);
>           if (!ret)
> diff --git a/src/qemu/qemu_process.c b/src/qemu/qemu_process.c
> index b1d8a32..3544716 100644
> --- a/src/qemu/qemu_process.c
> +++ b/src/qemu/qemu_process.c
> @@ -3756,6 +3756,7 @@ int qemuProcessStart(virConnectPtr conn,
>       struct qemuProcessHookData hookData;
>       unsigned long cur_balloon;
>       size_t i;
> +    bool rawio_set = false;
>       char *nodeset = NULL;
>       virBitmapPtr nodemask = NULL;
>       unsigned int stop_flags;
> @@ -4122,13 +4123,15 @@ int qemuProcessStart(virConnectPtr conn,
>           virDomainDeviceDef dev;
>           virDomainDiskDefPtr disk = vm->def->disks[i];
>
> -        if (vm->def->disks[i]->rawio == 1)
> +        if (vm->def->disks[i]->rawio == 1) {
>   #ifdef CAP_SYS_RAWIO
>               virCommandAllowCap(cmd, CAP_SYS_RAWIO);
>   #else
>               virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
>                              _("Raw I/O is not supported on this platform"));
>   #endif
> +            rawio_set = true;
> +        }

Interesting. So if rawio is requested we shout an error but don't fail 
actually. I think we are missing 'goto cleanup' here.

>
>           dev.type = VIR_DOMAIN_DEVICE_DISK;
>           dev.data.disk = disk;
> @@ -4139,6 +4142,21 @@ int qemuProcessStart(virConnectPtr conn,
>               goto cleanup;
>       }
>
> +    /* If rawio not already set, check hostdevs as well */
> +    if (!rawio_set) {
> +        for (i = 0; i < vm->def->nhostdevs; i++) {
> +            virDomainHostdevSubsysSCSIPtr scsisrc =
> +                &vm->def->hostdevs[i]->source.subsys.u.scsi;
> +            if (scsisrc->rawio == 1)
> +#ifdef CAP_SYS_RAWIO
> +                virCommandAllowCap(cmd, CAP_SYS_RAWIO);
> +#else
> +                virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
> +                               _("Raw I/O is not supported on this platform"));
> +#endif

And here too then.

> +        }
> +    }
> +
>       virCommandSetPreExecHook(cmd, qemuProcessHook, &hookData);
>       virCommandSetMaxProcesses(cmd, cfg->maxProcesses);
>       virCommandSetMaxFiles(cmd, cfg->maxFiles);
>

Michal