Re: [PATCH v3 08/19] backends/iommufd: Introduce helper function iommufd_backend_get_device_info()

[Cédric Le Goater]

On 4/29/24 08:50, Zhenzhong Duan wrote:
> Introduce a helper function iommufd_backend_get_device_info() to get
> host IOMMU related information through iommufd uAPI.
>
> Signed-off-by: Yi Liu <yi.l.liu@intel.com>
> Signed-off-by: Yi Sun <yi.y.sun@linux.intel.com>
> Signed-off-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
> ---
>   include/sysemu/iommufd.h |  4 ++++
>   backends/iommufd.c       | 24 +++++++++++++++++++++++-
>   2 files changed, 27 insertions(+), 1 deletion(-)
>
> diff --git a/include/sysemu/iommufd.h b/include/sysemu/iommufd.h
> index 6a9fb0007a..e9593637a3 100644
> --- a/include/sysemu/iommufd.h
> +++ b/include/sysemu/iommufd.h
> @@ -17,6 +17,7 @@
>   #include "qom/object.h"
>   #include "exec/hwaddr.h"
>   #include "exec/cpu-common.h"
> +#include <linux/iommufd.h>
>   #include "sysemu/host_iommu_device.h"
>   
>   #define TYPE_IOMMUFD_BACKEND "iommufd"
> @@ -47,6 +48,9 @@ int iommufd_backend_map_dma(IOMMUFDBackend *be, uint32_t 
> ioas_id, hwaddr iova,
>                               ram_addr_t size, void *vaddr, bool readonly);
>   int iommufd_backend_unmap_dma(IOMMUFDBackend *be, uint32_t ioas_id,
>                                 hwaddr iova, ram_addr_t size);
> +int iommufd_backend_get_device_info(IOMMUFDBackend *be, uint32_t devid,
> +                                    enum iommu_hw_info_type *type,
> +                                    void *data, uint32_t len, Error **errp);
>   
>   #define TYPE_HOST_IOMMU_DEVICE_IOMMUFD TYPE_HOST_IOMMU_DEVICE "-iommufd"
>   OBJECT_DECLARE_TYPE(HostIOMMUDeviceIOMMUFD, HostIOMMUDeviceIOMMUFDClass,
> diff --git a/backends/iommufd.c b/backends/iommufd.c
> index 19e46194a2..d61209788a 100644
> --- a/backends/iommufd.c
> +++ b/backends/iommufd.c
> @@ -19,7 +19,6 @@
>   #include "monitor/monitor.h"
>   #include "trace.h"
>   #include <sys/ioctl.h>
> -#include <linux/iommufd.h>
>   
>   static void iommufd_backend_init(Object *obj)
>   {
> @@ -211,6 +210,29 @@ int iommufd_backend_unmap_dma(IOMMUFDBackend *be, uint32_t 
> ioas_id,
>       return ret;
>   }
>   
> +int iommufd_backend_get_device_info(IOMMUFDBackend *be, uint32_t devid,
> +                                    enum iommu_hw_info_type *type,
> +                                    void *data, uint32_t len, Error **errp)

When taking an 'Error **' argument, routines preferably return a bool.

Thanks,

C.



 
> +{
> +    struct iommu_hw_info info = {
> +        .size = sizeof(info),
> +        .dev_id = devid,
> +        .data_len = len,
> +        .data_uptr = (uintptr_t)data,
> +    };
> +    int ret;
> +
> +    ret = ioctl(be->fd, IOMMU_GET_HW_INFO, &info);
> +    if (ret) {
> +        error_setg_errno(errp, errno, "Failed to get hardware info");
> +    } else {
> +        g_assert(type);
> +        *type = info.out_data_type;
> +    }
> +
> +    return ret;
> +}
> +
>   static const TypeInfo types[] = {
>       {
>           .name = TYPE_IOMMUFD_BACKEND,