Re: [Qemu-devel] [RFC 1/4] Allocate non-RAM MemoryRegion from user pointer

[Paolo Bonzini]

Il 17/04/2014 19:29, Alvise Rigo ha scritto:
> +
> +void memory_region_init_ptr(MemoryRegion *mr,
> +                                Object *owner,
> +                                const char *name,
> +                                uint64_t size,
> +                                void *ptr)
> +{
> +    memory_region_init(mr, owner, name, size);
> +    mr->terminates = true;
> +    mr->destructor = memory_region_destructor_ram_from_ptr;
> +    mr->ram_addr = qemu_ram_alloc_from_ptr(size, ptr, mr);
> +    mr->alloc_from_ptr = true;
>  }

I don't understand.  How is this different from 
memory_region_init_ram_ptr, and why should the IOMMU be bypassed?

Paolo