Re: [PATCH 09/22] vfio/container.c: use QOM casts where appropriate

["Cédric Le Goater" <clg@redhat.com>]

On 7/15/25 11:25, Mark Cave-Ayland wrote:
> Use QOM casts to convert between VFIOUserContainer and VFIOContainerBase instead
> of accessing bcontainer directly.
> 
> Signed-off-by: Mark Cave-Ayland <mark.caveayland@nutanix.com>


Reviewed-by: Cédric Le Goater <clg@redhat.com>

Thanks,

C.


> ---
>   hw/vfio-user/container.c | 26 +++++++++++---------------
>   1 file changed, 11 insertions(+), 15 deletions(-)
> 
> diff --git a/hw/vfio-user/container.c b/hw/vfio-user/container.c
> index d318e6a339..025db93ff3 100644
> --- a/hw/vfio-user/container.c
> +++ b/hw/vfio-user/container.c
> @@ -24,16 +24,14 @@
>    */
>   static void vfio_user_listener_begin(VFIOContainerBase *bcontainer)
>   {
> -    VFIOUserContainer *container = container_of(bcontainer, VFIOUserContainer,
> -                                                 bcontainer);
> +    VFIOUserContainer *container = VFIO_IOMMU_USER(bcontainer);
>   
>       container->proxy->async_ops = true;
>   }
>   
>   static void vfio_user_listener_commit(VFIOContainerBase *bcontainer)
>   {
> -    VFIOUserContainer *container = container_of(bcontainer, VFIOUserContainer,
> -                                            bcontainer);
> +    VFIOUserContainer *container = VFIO_IOMMU_USER(bcontainer);
>   
>       /* wait here for any async requests sent during the transaction */
>       container->proxy->async_ops = false;
> @@ -44,8 +42,8 @@ static int vfio_user_dma_unmap(const VFIOContainerBase *bcontainer,
>                                  hwaddr iova, ram_addr_t size,
>                                  IOMMUTLBEntry *iotlb, bool unmap_all)
>   {
> -    VFIOUserContainer *container = container_of(bcontainer, VFIOUserContainer,
> -                                            bcontainer);
> +    VFIOUserContainer *container = VFIO_IOMMU_USER(bcontainer);
> +
>       Error *local_err = NULL;
>       int ret = 0;
>   
> @@ -88,8 +86,8 @@ static int vfio_user_dma_map(const VFIOContainerBase *bcontainer, hwaddr iova,
>                                ram_addr_t size, void *vaddr, bool readonly,
>                                MemoryRegion *mrp)
>   {
> -    VFIOUserContainer *container = container_of(bcontainer, VFIOUserContainer,
> -                                                bcontainer);
> +    VFIOUserContainer *container = VFIO_IOMMU_USER(bcontainer);
> +
>       int fd = memory_region_get_fd(mrp);
>       Error *local_err = NULL;
>       int ret;
> @@ -177,8 +175,7 @@ static int vfio_user_query_dirty_bitmap(const VFIOContainerBase *bcontainer,
>   
>   static bool vfio_user_setup(VFIOContainerBase *bcontainer, Error **errp)
>   {
> -    VFIOUserContainer *container = container_of(bcontainer, VFIOUserContainer,
> -                                                bcontainer);
> +    VFIOUserContainer *container = VFIO_IOMMU_USER(bcontainer);
>   
>       assert(container->proxy->dma_pgsizes != 0);
>       bcontainer->pgsizes = container->proxy->dma_pgsizes;
> @@ -222,7 +219,7 @@ vfio_user_container_connect(AddressSpace *as, VFIODevice *vbasedev,
>           goto put_space_exit;
>       }
>   
> -    bcontainer = &container->bcontainer;
> +    bcontainer = VFIO_IOMMU(container);
>   
>       ret = ram_block_uncoordinated_discard_disable(true);
>       if (ret) {
> @@ -267,7 +264,7 @@ put_space_exit:
>   
>   static void vfio_user_container_disconnect(VFIOUserContainer *container)
>   {
> -    VFIOContainerBase *bcontainer = &container->bcontainer;
> +    VFIOContainerBase *bcontainer = VFIO_IOMMU(container);
>       VFIOIOMMUClass *vioc = VFIO_IOMMU_GET_CLASS(bcontainer);
>       VFIOAddressSpace *space = bcontainer->space;
>   
> @@ -295,7 +292,7 @@ static bool vfio_user_device_get(VFIOUserContainer *container,
>   
>       vbasedev->fd = -1;
>   
> -    vfio_device_prepare(vbasedev, &container->bcontainer, &info);
> +    vfio_device_prepare(vbasedev, VFIO_IOMMU(container), &info);
>   
>       return true;
>   }
> @@ -319,8 +316,7 @@ static bool vfio_user_device_attach(const char *name, VFIODevice *vbasedev,
>   
>   static void vfio_user_device_detach(VFIODevice *vbasedev)
>   {
> -    VFIOUserContainer *container = container_of(vbasedev->bcontainer,
> -                                                VFIOUserContainer, bcontainer);
> +    VFIOUserContainer *container = VFIO_IOMMU_USER(vbasedev->bcontainer);
>   
>       vfio_device_unprepare(vbasedev);
>