Re: [RFC PATCH 13/16] kvm tools: keep track of registered memory banks in struct kvm

[Sasha Levin <levinsasha928@gmail.com>]

On 11/12/2012 06:57 AM, Will Deacon wrote:
> When registering memory banks for a guest, it is useful to keep the
> range information around for translating between guest and host address
> spaces.
> 
> This patch adds a list of kvm_mem_bank structures to struct kvm, which
> is updated when a new bank is registered.
> 
> Signed-off-by: Will Deacon <will.deacon@arm.com>
> ---
>  tools/kvm/include/kvm/kvm.h |    8 ++++++++
>  tools/kvm/kvm.c             |   23 ++++++++++++++++++++++-
>  2 files changed, 30 insertions(+), 1 deletions(-)
> 
> diff --git a/tools/kvm/include/kvm/kvm.h b/tools/kvm/include/kvm/kvm.h
> index cf959ea..96dd81b 100644
> --- a/tools/kvm/include/kvm/kvm.h
> +++ b/tools/kvm/include/kvm/kvm.h
> @@ -35,6 +35,13 @@ struct kvm_ext {
>  	int code;
>  };
>  
> +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.

>  struct kvm {
>  	struct kvm_arch		arch;
>  	struct kvm_config	cfg;
> @@ -49,6 +56,7 @@ struct kvm {
>  	u64			ram_size;
>  	void			*ram_start;
>  	u64			ram_pagesize;
> +	struct list_head	mem_banks;

These memory banks actually look like a perfect example to use our augmented interval rb-tree,
can we switch them to use it, or is it a list on purpose?


Thanks,
Sasha