Re: [Qemu-devel] [PATCH qemu v10 11/14] spapr_pci_vfio: Enable multiple groups per container

[Thomas Huth <thuth@redhat.com>]

On Mon,  6 Jul 2015 12:11:07 +1000
Alexey Kardashevskiy <aik@ozlabs.ru> wrote:

> This enables multiple IOMMU groups in one VFIO container which means
> that multiple devices from different groups can share the same IOMMU
> table (or tables if DDW).
> 
> This removes a group id from vfio_container_ioctl(). The kernel support
> is required for this; if the host kernel does not have the support,
> it will allow only one group per container. The PHB's "iommuid" property
> is ignored. The ioctl is called for every container attached to
> the address space. At the moment there is just one container anyway.
> 
> If there is no container attached to the address space,
> vfio_container_do_ioctl() returns -1.
> 
> This removes casts to sPAPRPHBVFIOState as none of sPAPRPHBVFIOState
> members is accessed here.
> 
> Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
> Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
> ---
>  hw/ppc/spapr_pci_vfio.c | 17 ++++++-----------
>  hw/vfio/common.c        | 20 ++++++--------------
>  include/hw/vfio/vfio.h  |  2 +-
>  3 files changed, 13 insertions(+), 26 deletions(-)
...
> diff --git a/hw/vfio/common.c b/hw/vfio/common.c
> index b1045da..89ef37b 100644
> --- a/hw/vfio/common.c
> +++ b/hw/vfio/common.c
> @@ -918,34 +918,26 @@ void vfio_put_base_device(VFIODevice *vbasedev)
>      close(vbasedev->fd);
>  }
>  
> -static int vfio_container_do_ioctl(AddressSpace *as, int32_t groupid,
> +static int vfio_container_do_ioctl(AddressSpace *as,
>                                     int req, void *param)
>  {
> -    VFIOGroup *group;
>      VFIOContainer *container;
>      int ret = -1;
> +    VFIOAddressSpace *space = vfio_get_address_space(as);
>  
> -    group = vfio_get_group(groupid, as);
> -    if (!group) {
> -        error_report("vfio: group %d not registered", groupid);
> -        return ret;
> -    }
> -
> -    container = group->container;
> -    if (group->container) {
> +    QLIST_FOREACH(container, &space->containers, next) {
>          ret = ioctl(container->fd, req, param);
>          if (ret < 0) {
>              error_report("vfio: failed to ioctl %d to container: ret=%d, %s",
>                           _IOC_NR(req) - VFIO_BASE, ret, strerror(errno));
> +            return -errno;
>          }
>      }
>  
> -    vfio_put_group(group);
> -
>      return ret;
>  }
>  
> -int vfio_container_ioctl(AddressSpace *as, int32_t groupid,
> +int vfio_container_ioctl(AddressSpace *as,
>                           int req, void *param)

You could easily fit that into one line now.

>  {
>      /* We allow only certain ioctls to the container */
> @@ -960,5 +952,5 @@ int vfio_container_ioctl(AddressSpace *as, int32_t groupid,
>          return -1;
>      }
>  
> -    return vfio_container_do_ioctl(as, groupid, req, param);
> +    return vfio_container_do_ioctl(as, req, param);
>  }
> diff --git a/include/hw/vfio/vfio.h b/include/hw/vfio/vfio.h
> index 0b26cd8..76b5744 100644
> --- a/include/hw/vfio/vfio.h
> +++ b/include/hw/vfio/vfio.h
> @@ -3,7 +3,7 @@
>  
>  #include "qemu/typedefs.h"
>  
> -extern int vfio_container_ioctl(AddressSpace *as, int32_t groupid,
> +extern int vfio_container_ioctl(AddressSpace *as,
>                                  int req, void *param);

Dito.

Apart from the two cosmetic nits, patch looks fine to me:

Reviewed-by: Thomas Huth <thuth@redhat.com>