[libvirt] [PATCH 2/7] prevent hot unplugging multi function PCI device

[shu ming]

Hi
    I applied these pacches to libvirt tree

8077d64f964705c1034555abeea38773532b762f

And built a qemu-kvm from the upstream qemu-kvm tree version 0.14.  I 
tested these new binaries on my Redhat Enterprise Linux 6.1 GA.

Now I can have multiple function devices after I changed the VM XML 
config file manually, please see the 'lspci' output below.  Also, I can 
hotplug one device, but it seems that unplugging it failed.
-------------------------------------------------------------------------------------
[root at kvm-rhel-6 qemu]# virsh qemu-monitor-command
kvm-rhel-6.1-multifunction-1 --hmp 'device_add
lsi,id=scsi10,bus=pci.0,addr=0x7.0x00'

VM: **In the VM, 'lspci" can see one line added:

VM: **00:07.0 SCSI storage controller: LSI logic / Symbios Logic 5sc895a

[root at kvm-rhel-6 qemu]# virsh qemu-monitor-command
kvm-rhel-6.1-multifunction-1 --hmp 'device_del
lsi,id=scsi10,bus=pci.0,addr=0x7.0x00'
Device 'lsi,id=scsi10,bus=pci.0,addr=0x7.0x00' not found


---------------------------------------------------------------------------------------------------------------
#lspci
  00:00.0 Host bridge: Intel Corporation 440FX - 82441FX PMC [Natoma] (rev
  02)
  00:01.0 ISA bridge: Intel Corporation 82371SB PIIX3 ISA [Natoma/Triton II]
  00:01.1 IDE interface: Intel Coporation 82371SB PIIX3 IDE [Natoma/Triton
  II]
  00:01.2 USB Controller: Intel Corporation 82371SB PIIX3 USB Natoma/Triton
  II]
  00:01.3 Bridge: Intel Corporation 82371AB/EB/MB PIIX4 ACPI (rev 03)
  00:02.0 VGA compatible controller: Cirrus Logic GD 5446
  00:03.0 Ethernet controller: Red Hat, Inc Virtio network device   ---> 
function 0
  00:03.1 Ethernet controller: Red Hat, Inc Virtio network device
  00:03.2 Ethernet controller: Red Hat, Inc Virtio network device
  00:03.3 Ethernet controller: Red Hat, Inc Virtio network device
  00:03.4 Ethernet controller: Red Hat, Inc Virtio network device
  00:03.5 Ethernet controller: Red Hat, Inc Virtio network device
  00:03.6 Ethernet controller: Red Hat, Inc Virtio network device
  00:03.7 Ethernet controller: Red Hat, Inc Virtio network device  ---> 
function 7
  00:04.0 Audio device: Intel Corporation 82801FB/FBM/FR/FW/FRW
(ICH6 Family)
  High
  00:05.0 SCSI storage controller: Red Hat, Inc Virtio bloc device
  00:06.0 RAM memory: Red Hat, Inc Virtio memory balloon



Daniel P. Berrange:
> On Fri, May 27, 2011 at 06:20:10PM +0800, Wen Congyang wrote:
>> We do not support to hot unplug multi function PCI device now. If the device is
>> one function of multi function PCI device, we shoul not allow to hot unplugg
>> it.
>> ---
>>   src/qemu/qemu_hotplug.c |   52 +++++++++++++++++++++++++++++++++++++++++++++++
>>   1 files changed, 52 insertions(+), 0 deletions(-)
>>
>> diff --git a/src/qemu/qemu_hotplug.c b/src/qemu/qemu_hotplug.c
>> index 3cf7d35..e98c677 100644
>> --- a/src/qemu/qemu_hotplug.c
>> +++ b/src/qemu/qemu_hotplug.c
>> @@ -1100,6 +1100,30 @@ static inline int qemuFindDisk(virDomainDefPtr def, const char *dst)
>>       return -1;
>>   }
>>
>> +static int qemuComparePCIDevice(virDomainDefPtr def ATTRIBUTE_UNUSED,
>> +                                virDomainDeviceInfoPtr dev1,
>> +                                void *opaque)
>> +{
>> +    virDomainDeviceInfoPtr dev2 = opaque;
>> +
>> +    if (dev1->type !=  VIR_DOMAIN_DEVICE_ADDRESS_TYPE_PCI ||
>> +        dev2->type != VIR_DOMAIN_DEVICE_ADDRESS_TYPE_PCI)
>> +        return 0;
>> +
>> +    if (dev1->addr.pci.slot == dev2->addr.pci.slot&&
>> +        dev1->addr.pci.function != dev2->addr.pci.function)
>> +        return -1;
>> +    return 0;
>> +}
>> +
>> +static bool qemuIsMultiFunctionDevice(virDomainDefPtr def,
>> +                                      virDomainDeviceInfoPtr dev)
>> +{
>> +    if (virDomainDeviceInfoIterate(def, qemuComparePCIDevice, dev)<  0)
>> +        return true;
>> +    return false;
>> +}
>> +
>>
>>   int qemuDomainDetachPciDiskDevice(struct qemud_driver *driver,
>>                                     virDomainObjPtr vm,
>> @@ -1121,6 +1145,13 @@ int qemuDomainDetachPciDiskDevice(struct qemud_driver *driver,
>>
>>       detach = vm->def->disks[i];
>>
>> +    if (qemuIsMultiFunctionDevice(vm->def,&detach->info)) {
>> +        qemuReportError(VIR_ERR_OPERATION_FAILED,
>> +                        _("cannot hot unplug multifunction PCI device: %s"),
>> +                        dev->data.disk->dst);
>> +        goto cleanup;
>> +    }
>> +
>>       if (qemuCgroupControllerActive(driver, VIR_CGROUP_CONTROLLER_DEVICES)) {
>>           if (virCgroupForDomain(driver->cgroup, vm->def->name,&cgroup, 0) != 0) {
>>               qemuReportError(VIR_ERR_INTERNAL_ERROR,
>> @@ -1351,6 +1382,13 @@ int qemuDomainDetachPciControllerDevice(struct qemud_driver *driver,
>>           goto cleanup;
>>       }
>>
>> +    if (qemuIsMultiFunctionDevice(vm->def,&detach->info)) {
>> +        qemuReportError(VIR_ERR_OPERATION_FAILED,
>> +                        _("cannot hot unplug multifunction PCI device: %s"),
>> +                        dev->data.disk->dst);
>> +        goto cleanup;
>> +    }
>> +
>>       if (qemuDomainControllerIsBusy(vm, detach)) {
>>           qemuReportError(VIR_ERR_OPERATION_FAILED, "%s",
>>                           _("device cannot be detached: device is busy"));
>> @@ -1438,6 +1476,13 @@ int qemuDomainDetachNetDevice(struct qemud_driver *driver,
>>           goto cleanup;
>>       }
>>
>> +    if (qemuIsMultiFunctionDevice(vm->def,&detach->info)) {
>> +        qemuReportError(VIR_ERR_OPERATION_FAILED,
>> +                        _("cannot hot unplug multifunction PCI device :%s"),
>> +                        dev->data.disk->dst);
>> +        goto cleanup;
>> +    }
>> +
>>       if ((vlan = qemuDomainNetVLAN(detach))<  0) {
>>           qemuReportError(VIR_ERR_OPERATION_FAILED,
>>                           "%s", _("unable to determine original VLAN"));
>> @@ -1567,6 +1612,13 @@ int qemuDomainDetachHostPciDevice(struct qemud_driver *driver,
>>           return -1;
>>       }
>>
>> +    if (qemuIsMultiFunctionDevice(vm->def,&detach->info)) {
>> +        qemuReportError(VIR_ERR_OPERATION_FAILED,
>> +                        _("cannot hot unplug multifunction PCI device: %s"),
>> +                        dev->data.disk->dst);
>> +        return -1;
>> +    }
>> +
>>       if (!virDomainDeviceAddressIsValid(&detach->info,
>>                                          VIR_DOMAIN_DEVICE_ADDRESS_TYPE_PCI)) {
>>           qemuReportError(VIR_ERR_OPERATION_FAILED,
> ACK
>
> Daniel