[v3,2/2] intel_iommu: allow migration

IOMMU needs to be migrated before all the PCI devices (in case there are
devices that will request for address translation). So marking it with a
priority higher than the default (which PCI devices and other belong).
Migration framework handled the rest.

Signed-off-by: Peter Xu <peterx@redhat.com>
---
 hw/i386/intel_iommu.c       | 22 +++++++++++++++++++++-
 include/migration/vmstate.h |  1 +
 2 files changed, 22 insertions(+), 1 deletion(-)

On 2017年01月06日 12:06, Peter Xu wrote:
> IOMMU needs to be migrated before all the PCI devices (in case there are
> devices that will request for address translation). So marking it with a
> priority higher than the default (which PCI devices and other belong).
> Migration framework handled the rest.
>
> Signed-off-by: Peter Xu <peterx@redhat.com>
> ---
>   hw/i386/intel_iommu.c       | 22 +++++++++++++++++++++-
>   include/migration/vmstate.h |  1 +
>   2 files changed, 22 insertions(+), 1 deletion(-)
>
> diff --git a/hw/i386/intel_iommu.c b/hw/i386/intel_iommu.c
> index 5f3e351..119217b 100644
> --- a/hw/i386/intel_iommu.c
> +++ b/hw/i386/intel_iommu.c
> @@ -1996,7 +1996,27 @@ static void vtd_iommu_notify_flag_changed(MemoryRegion *iommu,
>   
>   static const VMStateDescription vtd_vmstate = {
>       .name = "iommu-intel",
> -    .unmigratable = 1,
> +    .version_id = 1,
> +    .minimum_version_id = 1,
> +    .priority = MIG_PRI_IOMMU,
> +    .fields = (VMStateField[]) {
> +        VMSTATE_UINT64(root, IntelIOMMUState),
> +        VMSTATE_UINT64(intr_root, IntelIOMMUState),
> +        VMSTATE_UINT64(iq, IntelIOMMUState),
> +        VMSTATE_UINT32(intr_size, IntelIOMMUState),
> +        VMSTATE_UINT16(iq_head, IntelIOMMUState),
> +        VMSTATE_UINT16(iq_tail, IntelIOMMUState),
> +        VMSTATE_UINT16(iq_size, IntelIOMMUState),
> +        VMSTATE_UINT16(next_frcd_reg, IntelIOMMUState),
> +        VMSTATE_UINT8_ARRAY(csr, IntelIOMMUState, DMAR_REG_SIZE),

Do we need migrate wmask, w1cmask, womask too?

> +        VMSTATE_UINT8(iq_last_desc_type, IntelIOMMUState),
> +        VMSTATE_BOOL(root_extended, IntelIOMMUState),
> +        VMSTATE_BOOL(dmar_enabled, IntelIOMMUState),
> +        VMSTATE_BOOL(qi_enabled, IntelIOMMUState),
> +        VMSTATE_BOOL(intr_enabled, IntelIOMMUState),
> +        VMSTATE_BOOL(intr_eime, IntelIOMMUState),
> +        VMSTATE_END_OF_LIST()
> +    }
>   };
>   
>   static const MemoryRegionOps vtd_mem_ops = {
> diff --git a/include/migration/vmstate.h b/include/migration/vmstate.h
> index 1a22887..2125829 100644
> --- a/include/migration/vmstate.h
> +++ b/include/migration/vmstate.h
> @@ -188,6 +188,7 @@ enum VMStateFlags {
>   
>   typedef enum {
>       MIG_PRI_DEFAULT = 0,
> +    MIG_PRI_IOMMU,              /* Must happen before PCI devices */
>       MIG_PRI_MAX,
>   } MigrationPriority;
>   

I think we should reset iotlb and context cache in post_load() too.

Thanks

On Fri, Jan 06, 2017 at 03:05:47PM +0800, Jason Wang wrote:
> 
> 
> On 2017年01月06日 12:06, Peter Xu wrote:
> >IOMMU needs to be migrated before all the PCI devices (in case there are
> >devices that will request for address translation). So marking it with a
> >priority higher than the default (which PCI devices and other belong).
> >Migration framework handled the rest.
> >
> >Signed-off-by: Peter Xu <peterx@redhat.com>
> >---
> >  hw/i386/intel_iommu.c       | 22 +++++++++++++++++++++-
> >  include/migration/vmstate.h |  1 +
> >  2 files changed, 22 insertions(+), 1 deletion(-)
> >
> >diff --git a/hw/i386/intel_iommu.c b/hw/i386/intel_iommu.c
> >index 5f3e351..119217b 100644
> >--- a/hw/i386/intel_iommu.c
> >+++ b/hw/i386/intel_iommu.c
> >@@ -1996,7 +1996,27 @@ static void vtd_iommu_notify_flag_changed(MemoryRegion *iommu,
> >  static const VMStateDescription vtd_vmstate = {
> >      .name = "iommu-intel",
> >-    .unmigratable = 1,
> >+    .version_id = 1,
> >+    .minimum_version_id = 1,
> >+    .priority = MIG_PRI_IOMMU,
> >+    .fields = (VMStateField[]) {
> >+        VMSTATE_UINT64(root, IntelIOMMUState),
> >+        VMSTATE_UINT64(intr_root, IntelIOMMUState),
> >+        VMSTATE_UINT64(iq, IntelIOMMUState),
> >+        VMSTATE_UINT32(intr_size, IntelIOMMUState),
> >+        VMSTATE_UINT16(iq_head, IntelIOMMUState),
> >+        VMSTATE_UINT16(iq_tail, IntelIOMMUState),
> >+        VMSTATE_UINT16(iq_size, IntelIOMMUState),
> >+        VMSTATE_UINT16(next_frcd_reg, IntelIOMMUState),
> >+        VMSTATE_UINT8_ARRAY(csr, IntelIOMMUState, DMAR_REG_SIZE),
> 
> Do we need migrate wmask, w1cmask, womask too?

Should not. Although we are using arrays here, they should be only
configured during vtd_define_*() and should be constant values for the
whole lifecycle of the device (which is mostly decided by the spec).

Thanks,

-- peterx