Re: [RFC PATCH v1 2/4] Add migration functions for VFIO devices

Kirti Wankhede
2018-10-17T21:03:43Z

On 10/17/2018 2:30 PM, Cornelia Huck wrote:
> On Tue, 16 Oct 2018 23:42:36 +0530
> Kirti Wankhede <kwankhede@nvidia.com> wrote:
>
>> - Migration function are implemented for VFIO_DEVICE_TYPE_PCI device.
>> - Added SaveVMHandlers and implemented all basic functions required for live
>> migration.
>> - Added VM state change handler to know running or stopped state of VM.
>> - Added migration state change notifier to get notification on migration state
>> change. This state is translated to VFIO device state and conveyed to vendor
>> driver.
>>
>> Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
>> Reviewed-by: Neo Jia <cjia@nvidia.com>
>> ---
>> hw/vfio/Makefile.objs | 2 +-
>> hw/vfio/migration.c | 716 ++++++++++++++++++++++++++++++++++++++++++
>> include/hw/vfio/vfio-common.h | 23 ++
>> 3 files changed, 740 insertions(+), 1 deletion(-)
>> create mode 100644 hw/vfio/migration.c
>>
>> diff --git a/hw/vfio/Makefile.objs b/hw/vfio/Makefile.objs
>> index a2e7a0a7cf02..6206ad47e90e 100644
>> --- a/hw/vfio/Makefile.objs
>> +++ b/hw/vfio/Makefile.objs
>> @@ -1,6 +1,6 @@
>> ifeq ($(CONFIG_LINUX), y)
>> obj-$(CONFIG_SOFTMMU) += common.o
>> -obj-$(CONFIG_PCI) += pci.o pci-quirks.o display.o
>> +obj-$(CONFIG_PCI) += pci.o pci-quirks.o display.o migration.o
>
> I don't think you want to make this explicitly pci-specific, but build
> in a proper split of common infrastructure and pci handling from the
> beginning.
>

Yes, I'll split it in next version.

Thanks,
Kirti

>> obj-$(CONFIG_VFIO_CCW) += ccw.o
>> obj-$(CONFIG_SOFTMMU) += platform.o
>> obj-$(CONFIG_VFIO_XGMAC) += calxeda-xgmac.o
>> diff --git a/hw/vfio/migration.c b/hw/vfio/migration.c
>> new file mode 100644
>> index 000000000000..8a4f515226e0
>> --- /dev/null
>> +++ b/hw/vfio/migration.c
>
> (...)
>
>> +static int vfio_save_device_config_state(QEMUFile *f, void *opaque)
>> +{
>> + VFIODevice *vbasedev = opaque;
>> +
>> + qemu_put_be64(f, VFIO_MIG_FLAG_DEV_CONFIG_STATE);
>> +
>> + if (vbasedev->type == VFIO_DEVICE_TYPE_PCI) {
>> + VFIOPCIDevice *vdev = container_of(vbasedev, VFIOPCIDevice, vbasedev);
>> + PCIDevice *pdev = &vdev->pdev;
>> + uint32_t msi_flags, msi_addr_lo, msi_addr_hi = 0, msi_data;
>> + bool msi_64bit;
>> + int i;
>> +
>> + for (i = 0; i < PCI_ROM_SLOT; i++) {
>> + uint32_t bar;
>> +
>> + bar = pci_default_read_config(pdev, PCI_BASE_ADDRESS_0 + i * 4, 4);
>> + qemu_put_be32(f, bar);
>> + }
>> +
>> + msi_flags = pci_default_read_config(pdev,
>> + pdev->msi_cap + PCI_MSI_FLAGS, 2);
>> + msi_64bit = (msi_flags & PCI_MSI_FLAGS_64BIT);
>> +
>> + msi_addr_lo = pci_default_read_config(pdev,
>> + pdev->msi_cap + PCI_MSI_ADDRESS_LO, 4);
>> + qemu_put_be32(f, msi_addr_lo);
>> +
>> + if (msi_64bit) {
>> + msi_addr_hi = pci_default_read_config(pdev,
>> + pdev->msi_cap + PCI_MSI_ADDRESS_HI,
>> + 4);
>> + }
>> + qemu_put_be32(f, msi_addr_hi);
>> +
>> + msi_data = pci_default_read_config(pdev,
>> + pdev->msi_cap + (msi_64bit ? PCI_MSI_DATA_64 : PCI_MSI_DATA_32),
>> + 2);
>> + qemu_put_be32(f, msi_data);
>> + }
>
> This is an example of a function that should go into a pci-specific
> file. Especially as config space is not a universal concept.
>
>> + qemu_put_be64(f, VFIO_MIG_FLAG_END_OF_STATE);
>> +
>> + return qemu_file_get_error(f);
>> +}