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Date: Wed, 26 Feb 2014 13:31:19 +0100
From: Igor Mammedov <imammedo@redhat.com>
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Subject: Re: [Qemu-devel] [PATCH v18 13/14] memory backend: fill memory
 backend ram fields
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To: Paolo Bonzini <pbonzini@redhat.com>
Cc: Hu Tao <hutao@cn.fujitsu.com>, lersek@redhat.com, qemu-devel@nongnu.org, Wanlong Gao <gaowanlong@cn.fujitsu.com>

On Wed, 26 Feb 2014 11:33:30 +0100
Paolo Bonzini <pbonzini@redhat.com> wrote:

> Il 26/02/2014 10:10, Igor Mammedov ha scritto:
> > if we assume that NUMA policies apply to every hostmem derived backend,
> > then we could realize() approach used by DEVICE. i.e.
> > set NUMA policies in hostmem.c:hostmemory_backend_memory_init()
> >
> > Add parent_complete field to ram-backend class and store there parent's
> > complete pointer. Then we can do:
> >
> > ram_backend_memory_init(UserCreatable *uc, Error **errp) {
> >     memory_region_init_ram();
> >     ...
> >     MEMORY_BACKEND_RAM_CLASS(uc)->parent_complete(uc, errp);
> >     ...
> > }
> >
> 
> The problem is that some backends might not be handled the same way. 
> For example, not all backends might produce a single void*/size_t pair 
> for the entire region.  Think of a "composite" backend that produces a 
> large memory region from two smaller ones.

I'd prefer to keep backends simple, with 1:1 mapping to memory regions.
Is there a need in composite one or something similar?

> 
> Paolo