Re: [PATCH v3 03/20] intel_iommu: Implement get_viommu_cap() callback

[Eric Auger]

Hi,

On 7/8/25 1:05 PM, Zhenzhong Duan wrote:
> Implement get_viommu_cap() callback and expose stage-1 capability for now.
>
> VFIO uses it to create nested parent domain which is further used to create
> nested domain in vIOMMU. All these will be implemented in following patches.
>
> Suggested-by: Yi Liu 
> Signed-off-by: Zhenzhong Duan 
> ---
>  hw/i386/intel_iommu.c | 12 
>  1 file changed, 12 insertions(+)
>
> diff --git a/hw/i386/intel_iommu.c b/hw/i386/intel_iommu.c
> index f0b1f90eff..702973da5c 100644
> --- a/hw/i386/intel_iommu.c
> +++ b/hw/i386/intel_iommu.c
> @@ -24,6 +24,7 @@
>  #include "qemu/main-loop.h"
>  #include "qapi/error.h"
>  #include "hw/sysbus.h"
> +#include "hw/iommu.h"
>  #include "intel_iommu_internal.h"
>  #include "hw/pci/pci.h"
>  #include "hw/pci/pci_bus.h"
> @@ -4412,6 +4413,16 @@ static void vtd_dev_unset_iommu_device(PCIBus *bus, 
> void *opaque, int devfn)
>  vtd_iommu_unlock(s);
>  }
>  
> +static uint64_t vtd_get_viommu_cap(void *opaque)
> +{
> +IntelIOMMUState *s = opaque;
> +uint64_t caps;
> +
> +caps = s->flts ? VIOMMU_CAP_STAGE1 : 0;
with CAP_HW_NESTED
Reviewed-by: Eric Auger 
Eric
> +
> +return caps;
> +}
> +
>  /* Unmap the whole range in the notifier's scope. */
>  static void vtd_address_space_unmap(VTDAddressSpace *as, IOMMUNotifier *n)
>  {
> @@ -4734,6 +4745,7 @@ static PCIIOMMUOps vtd_iommu_ops = {
>  .get_address_space = vtd_host_dma_iommu,
>  .set_iommu_device = vtd_dev_set_iommu_device,
>  .unset_iommu_device = vtd_dev_unset_iommu_device,
> +.get_viommu_cap = vtd_get_viommu_cap,
>  };
>  
>  static bool vtd_decide_config(IntelIOMMUState *s, Error **errp)

[PATCH v3 03/20] intel_iommu: Implement get_viommu_cap() callback

[Zhenzhong Duan]

Implement get_viommu_cap() callback and expose stage-1 capability for now.

VFIO uses it to create nested parent domain which is further used to create
nested domain in vIOMMU. All these will be implemented in following patches.

Suggested-by: Yi Liu 
Signed-off-by: Zhenzhong Duan 
---
 hw/i386/intel_iommu.c | 12 
 1 file changed, 12 insertions(+)

diff --git a/hw/i386/intel_iommu.c b/hw/i386/intel_iommu.c
index f0b1f90eff..702973da5c 100644
--- a/hw/i386/intel_iommu.c
+++ b/hw/i386/intel_iommu.c
@@ -24,6 +24,7 @@
 #include "qemu/main-loop.h"
 #include "qapi/error.h"
 #include "hw/sysbus.h"
+#include "hw/iommu.h"
 #include "intel_iommu_internal.h"
 #include "hw/pci/pci.h"
 #include "hw/pci/pci_bus.h"
@@ -4412,6 +4413,16 @@ static void vtd_dev_unset_iommu_device(PCIBus *bus, void 
*opaque, int devfn)
 vtd_iommu_unlock(s);
 }
 
+static uint64_t vtd_get_viommu_cap(void *opaque)
+{
+IntelIOMMUState *s = opaque;
+uint64_t caps;
+
+caps = s->flts ? VIOMMU_CAP_STAGE1 : 0;
+
+return caps;
+}
+
 /* Unmap the whole range in the notifier's scope. */
 static void vtd_address_space_unmap(VTDAddressSpace *as, IOMMUNotifier *n)
 {
@@ -4734,6 +4745,7 @@ static PCIIOMMUOps vtd_iommu_ops = {
 .get_address_space = vtd_host_dma_iommu,
 .set_iommu_device = vtd_dev_set_iommu_device,
 .unset_iommu_device = vtd_dev_unset_iommu_device,
+.get_viommu_cap = vtd_get_viommu_cap,
 };
 
 static bool vtd_decide_config(IntelIOMMUState *s, Error **errp)
-- 
2.47.1