Re: [RFC 1/4] memory: add memory_region_init_io_with_dev interface

[Jason Wang]

On 2020/9/9 上午12:41, Li Qiang wrote:
> Currently the MR is not explicitly connecting with its device instead of
> a opaque. In most situation this opaque is the deivce but it is not an
> enforcement. This patch adds a DeviceState member of to MemoryRegion
> we will use it in later patch.


I don't have a deep investigation. But I wonder whether we could make 
sure of owner instead of adding a new field here.

Thanks


> Signed-off-by: Li Qiang <liq3ea@163.com>
> ---
>   include/exec/memory.h |  9 +++++++++
>   softmmu/memory.c      | 15 +++++++++++++++
>   2 files changed, 24 insertions(+)
>
> diff --git a/include/exec/memory.h b/include/exec/memory.h
> index 0cfe987ab4..620fb12d9b 100644
> --- a/include/exec/memory.h
> +++ b/include/exec/memory.h
> @@ -404,6 +404,7 @@ struct MemoryRegion {
>       const char *name;
>       unsigned ioeventfd_nb;
>       MemoryRegionIoeventfd *ioeventfds;
> +    DeviceState *dev;
>   };
>   
>   struct IOMMUMemoryRegion {
> @@ -794,6 +795,14 @@ void memory_region_init_io(MemoryRegion *mr,
>                              const char *name,
>                              uint64_t size);
>   
> +void memory_region_init_io_with_dev(MemoryRegion *mr,
> +                           struct Object *owner,
> +                           const MemoryRegionOps *ops,
> +                           void *opaque,
> +                           const char *name,
> +                           uint64_t size,
> +                           DeviceState *dev);
> +
>   /**
>    * memory_region_init_ram_nomigrate:  Initialize RAM memory region.  Accesses
>    *                                    into the region will modify memory
> diff --git a/softmmu/memory.c b/softmmu/memory.c
> index 70b93104e8..2628c9d2d9 100644
> --- a/softmmu/memory.c
> +++ b/softmmu/memory.c
> @@ -1490,6 +1490,21 @@ void memory_region_init_io(MemoryRegion *mr,
>       mr->terminates = true;
>   }
>   
> +void memory_region_init_io_with_dev(MemoryRegion *mr,
> +                           Object *owner,
> +                           const MemoryRegionOps *ops,
> +                           void *opaque,
> +                           const char *name,
> +                           uint64_t size,
> +                           DeviceState *dev)
> +{
> +    memory_region_init(mr, owner, name, size);
> +    mr->ops = ops ? ops : &unassigned_mem_ops;
> +    mr->opaque = opaque;
> +    mr->terminates = true;
> +    mr->dev = dev;
> +}
> +
>   void memory_region_init_ram_nomigrate(MemoryRegion *mr,
>                                         Object *owner,
>                                         const char *name,