Re: [Qemu-devel] [PATCH v4 18/29] hostmem: add file-based HostMemoryBackend

[Paolo Bonzini]

Il 10/06/2014 10:30, Hu Tao ha scritto:
> On Tue, Jun 10, 2014 at 01:09:32AM -0400, Paolo Bonzini wrote:
> > > > > +#define TYPE_MEMORY_BACKEND_FILE "memory-backend-file"
> > > > how about naming it after what it really is? "memory-backend-hugepage"
> > > > Later we could split it into generic superclass mmap-ed
> > > > "memory-backend-file" and have TPH specific code moved into this backend.
> > >
> > > OK.
> >
> > Actually I don't think there's anything hugepage-specific in this backend
> > (except perhaps passing a path instead of a filename).  It could be used
> > with a tmpfs backing storage like /dev/shm.
>
> What's the point compared to memory-backend-ram?

That you can use shared memory, for example together with vhost-user.

> Igor suggested memory-backend-file be compiled only for Linux. Does this mean
> memory-backend-file shuold be compiled also for systems supporting tmpfs
> or like?

Yes, I think it should be compiled on all POSIX systems.  But it can be 
done later.

Paolo