On Fri, 2 Aug 2019 17:05:59 +0200
Jens Freimann <address@hidden> wrote:
> As usual block all vfio-pci devices from being migrated, but make an
> exception for failover primary devices. This is achieved by setting
> unmigratable to 0 but also add a migration blocker for all vfio-pci
> devices except failover primary devices. These will be unplugged before
> migration happens by the migration handler of the corresponding
> virtio-net standby device.
>
> Signed-off-by: Jens Freimann <address@hidden>
> ---
> hw/vfio/pci.c | 24 +++++++++++++++++++++++-
> hw/vfio/pci.h | 1 +
> 2 files changed, 24 insertions(+), 1 deletion(-)
>
> diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c
> index d6ae9bd4ac..398d26669b 100644
> --- a/hw/vfio/pci.c
> +++ b/hw/vfio/pci.c
> @@ -35,6 +35,9 @@
> #include "pci.h"
> #include "trace.h"
> #include "qapi/error.h"
> +#include "migration/blocker.h"
> +#include "qemu/option.h"
> +#include "qemu/option_int.h"
>
> #define TYPE_VFIO_PCI "vfio-pci"
> #define PCI_VFIO(obj) OBJECT_CHECK(VFIOPCIDevice, obj, TYPE_VFIO_PCI)
> @@ -2693,6 +2696,12 @@ static void vfio_unregister_req_notifier(VFIOPCIDevice
*vdev)
> vdev->req_enabled = false;
> }
>
> +static int has_standby_arg(void *opaque, const char *name,
> + const char *value, Error **errp)
> +{
> + return strcmp(name, "standby") == 0;
> +}
> +
> static void vfio_realize(PCIDevice *pdev, Error **errp)
> {
> VFIOPCIDevice *vdev = PCI_VFIO(pdev);
> @@ -2706,6 +2715,19 @@ static void vfio_realize(PCIDevice *pdev, Error **errp)
> int i, ret;
> bool is_mdev;
>
> + if (qemu_opt_foreach(pdev->qdev.opts, has_standby_arg,
> + (void *) pdev->qdev.opts, &err) == 0) {
> + error_setg(&vdev->migration_blocker,
> + "VFIO device doesn't support migration");
> + ret = migrate_add_blocker(vdev->migration_blocker, &err);
> + if (err) {
> + error_propagate(errp, err);
> + error_free(vdev->migration_blocker);
> + }
> + } else {
> + pdev->qdev.allow_unplug_during_migration = true;
I think you add this only in the next patch?
> + }
> +
> if (!vdev->vbasedev.sysfsdev) {
> if (!(~vdev->host.domain || ~vdev->host.bus ||
> ~vdev->host.slot || ~vdev->host.function)) {
> @@ -3148,7 +3170,7 @@ static Property vfio_pci_dev_properties[] = {
>
> static const VMStateDescription vfio_pci_vmstate = {
> .name = "vfio-pci",
> - .unmigratable = 1,
> + .unmigratable = 0,
> };
>
> static void vfio_pci_dev_class_init(ObjectClass *klass, void *data)
> diff --git a/hw/vfio/pci.h b/hw/vfio/pci.h
> index 27d58fc55b..0f6f8cb395 100644
> --- a/hw/vfio/pci.h
> +++ b/hw/vfio/pci.h
> @@ -169,6 +169,7 @@ typedef struct VFIOPCIDevice {
> bool no_vfio_ioeventfd;
> bool enable_ramfb;
> VFIODisplay *dpy;
> + Error *migration_blocker;
> } VFIOPCIDevice;
>
> uint32_t vfio_pci_read_config(PCIDevice *pdev, uint32_t addr, int len);
This patch interacts with support for vfio migration (last posted in
<address@hidden>, I've not seen
a later version yet.)
With that, we'd have three cases to consider:
1) device is a failover primary
2) device has a migration region
3) none of the above
Can 1) and 2) happen simultaneously? If yes, what should take
precedence?