From mboxrd@z Thu Jan  1 00:00:00 1970
From: Will Deacon <will.deacon@arm.com>
Subject: Re: [RFC PATCH 13/16] kvm tools: keep track of registered memory
 banks in struct kvm
Date: Tue, 13 Nov 2012 16:21:20 +0000
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Cc: "kvm@vger.kernel.org" <kvm@vger.kernel.org>,
	"penberg@kernel.org" <penberg@kernel.org>,
	Marc Zyngier <Marc.Zyngier@arm.com>,
	"c.dall@virtualopensystems.com" <c.dall@virtualopensystems.com>,
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To: Sasha Levin <levinsasha928@gmail.com>
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On Tue, Nov 13, 2012 at 04:09:05PM +0000, Sasha Levin wrote:
> On 11/13/2012 07:16 AM, Will Deacon wrote:
> > On Tue, Nov 13, 2012 at 04:37:38AM +0000, Sasha Levin wrote:
> >> On 11/12/2012 06:57 AM, Will Deacon wrote:
> >>> +struct kvm_mem_bank {
> >>> +	struct list_head	list;
> >>> +	unsigned long		guest_phys_addr;
> >>> +	void			*host_addr;
> >>> +	unsigned long		size;
> >>> +};
> >>
> >> Can we just reuse struct kvm_userspace_memory_region here? We're also using different
> >> data types for guest_phys_addr and size than whats in kvm_userspace_memory_region - that
> >> can't be good.
> > 
> > I looked briefly at doing that when I wrote the multi-bank stuff, but I hit
> > a couple of issues:
> > 
> > 	- kvmtool itself tends to use void * for host addresses, rather than
> > 	  the __u64 userspace_addr in kvm_userspace_memory_region
> > 
> > 	- kvm_userspace_memory_region is a superset of what we need (not the
> > 	  end of the world I guess)
> > 
> > so you end up casting address types a fair amount. Still, I'll revisit it
> > and see if I can come up with something cleaner.
> 
> That's a good point. We used void* while the kernel side is using u64, which
> looks odd.
> 
> In that case, let's get everything moved to u64 (obviously not in the scope of
> this patch series).

Ok, I'll update the size field to match in this patch series, then we can
tackle the address discrepancy separately.

Cheers,

Will