Re: [PATCH v6 2/9] vfio/{iommufd,container}: Remove caps::aw_bits

[Eric Auger]

On 7/22/24 23:13, Joao Martins wrote:
> Remove caps::aw_bits which requires the bcontainer::iova_ranges being
> initialized after device is actually attached. Instead defer that to
> .get_cap() and call vfio_device_get_aw_bits() directly.
>
> This is in preparation for HostIOMMUDevice::realize() being called early
> during attach_device().
>
> Suggested-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
> Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
> Reviewed-by: Cédric Le Goater <clg@redhat.com
Reviewed-by: Eric Auger <eric.auger@redhat.com>

Eric
> ---
>  include/sysemu/host_iommu_device.h | 3 ---
>  backends/iommufd.c                 | 3 ++-
>  hw/vfio/container.c                | 5 +----
>  hw/vfio/iommufd.c                  | 1 -
>  4 files changed, 3 insertions(+), 9 deletions(-)
>
> diff --git a/include/sysemu/host_iommu_device.h 
> b/include/sysemu/host_iommu_device.h
> index c1bf74ae2c7a..d1c10ff7c239 100644
> --- a/include/sysemu/host_iommu_device.h
> +++ b/include/sysemu/host_iommu_device.h
> @@ -19,12 +19,9 @@
>   * struct HostIOMMUDeviceCaps - Define host IOMMU device capabilities.
>   *
>   * @type: host platform IOMMU type.
> - *
> - * @aw_bits: host IOMMU address width. 0xff if no limitation.
>   */
>  typedef struct HostIOMMUDeviceCaps {
>      uint32_t type;
> -    uint8_t aw_bits;
>  } HostIOMMUDeviceCaps;
>  
>  #define TYPE_HOST_IOMMU_DEVICE "host-iommu-device"
> diff --git a/backends/iommufd.c b/backends/iommufd.c
> index 60a3d14bfab4..06b135111f30 100644
> --- a/backends/iommufd.c
> +++ b/backends/iommufd.c
> @@ -18,6 +18,7 @@
>  #include "qemu/error-report.h"
>  #include "monitor/monitor.h"
>  #include "trace.h"
> +#include "hw/vfio/vfio-common.h"
>  #include <sys/ioctl.h>
>  #include <linux/iommufd.h>
>  
> @@ -269,7 +270,7 @@ static int hiod_iommufd_get_cap(HostIOMMUDevice *hiod, 
> int cap, Error **errp)
>      case HOST_IOMMU_DEVICE_CAP_IOMMU_TYPE:
>          return caps->type;
>      case HOST_IOMMU_DEVICE_CAP_AW_BITS:
> -        return caps->aw_bits;
> +        return vfio_device_get_aw_bits(hiod->agent);
>      default:
>          error_setg(errp, "%s: unsupported capability %x", hiod->name, cap);
>          return -EINVAL;
> diff --git a/hw/vfio/container.c b/hw/vfio/container.c
> index ce9a858e5621..10cb4b4320ac 100644
> --- a/hw/vfio/container.c
> +++ b/hw/vfio/container.c
> @@ -1141,7 +1141,6 @@ static bool hiod_legacy_vfio_realize(HostIOMMUDevice 
> *hiod, void *opaque,
>      VFIODevice *vdev = opaque;
>  
>      hiod->name = g_strdup(vdev->name);
> -    hiod->caps.aw_bits = vfio_device_get_aw_bits(vdev);
>      hiod->agent = opaque;
>  
>      return true;
> @@ -1150,11 +1149,9 @@ static bool hiod_legacy_vfio_realize(HostIOMMUDevice 
> *hiod, void *opaque,
>  static int hiod_legacy_vfio_get_cap(HostIOMMUDevice *hiod, int cap,
>                                      Error **errp)
>  {
> -    HostIOMMUDeviceCaps *caps = &hiod->caps;
> -
>      switch (cap) {
>      case HOST_IOMMU_DEVICE_CAP_AW_BITS:
> -        return caps->aw_bits;
> +        return vfio_device_get_aw_bits(hiod->agent);
>      default:
>          error_setg(errp, "%s: unsupported capability %x", hiod->name, cap);
>          return -EINVAL;
> diff --git a/hw/vfio/iommufd.c b/hw/vfio/iommufd.c
> index 172553b1f7f8..5bb623879abe 100644
> --- a/hw/vfio/iommufd.c
> +++ b/hw/vfio/iommufd.c
> @@ -724,7 +724,6 @@ static bool hiod_iommufd_vfio_realize(HostIOMMUDevice 
> *hiod, void *opaque,
>  
>      hiod->name = g_strdup(vdev->name);
>      caps->type = type;
> -    caps->aw_bits = vfio_device_get_aw_bits(vdev);
>  
>      return true;
>  }