Re: [PATCH v3 1/5] efi: Add efi_init_ops variable

[Daniel Kiper <daniel.kiper@oracle.com>]

On Wed, Mar 26, 2014 at 12:56:23PM +0000, Matt Fleming wrote:
> On Tue, 25 Mar, at 09:57:52PM, Daniel Kiper wrote:
> > Add efi_init_ops variable which allows us to replace
> > EFI init functions on Xen with its specific stuff.
> >
> > This patch is based on Jan Beulich and Tang Liang work.
> >
> > Signed-off-by: Daniel Kiper <daniel.kiper@oracle.com>
> > Signed-off-by: Tang Liang <liang.tang@oracle.com>
> > ---
> >  arch/ia64/kernel/efi.c      |   30 +++++++++++++++++++++---------
> >  arch/x86/platform/efi/efi.c |   18 +++++++++++++-----
> >  drivers/firmware/efi/efi.c  |   26 ++++++++++++++++++++++++++
> >  include/linux/efi.h         |    8 ++++++++
> >  4 files changed, 68 insertions(+), 14 deletions(-)
>
> [...]
>
> > @@ -1118,6 +1118,14 @@ u64 efi_mem_attributes(unsigned long phys_addr)
> >  	return 0;
> >  }
> >
> > +struct efi_init_ops efi_init_ops = {
> > +	.efi_init = efi_init_generic,
> > +	.efi_reserve_boot_services = efi_reserve_boot_services_generic,
> > +	.efi_enter_virtual_mode = efi_enter_virtual_mode_generic,
> > +	.efi_mem_type = efi_mem_type_generic,
> > +	.efi_mem_attributes = efi_mem_attributes_generic
> > +};
>
> Please don't create another struct of EFI function pointers.
>
> After this we'll have 3 global efi structures defintions and 4 global
> efi objects on x86,
>
>   - struct efi_early [in the boot stub]
>   - struct efi ['efi_phys' before/'efi' after SetVirtualAddressMap()]
>   - struct efi_init_ops [for the benefit of xen]

What do you suggest? Should we fill all EFI related structures
in xen_efi_probe() (called from xen_start_kernel()) and later
they should be parsed by generic/x86 EFI initialization code?
I suppose that many variables will have NULL (or something relevant)
in Xen dom0 and it will require some changes in EFI initialization code.

> I have a big problem with exposing .efi_reserve_boot_services as an API.

Why? efi_reserve_boot_services() is public right now.

Daniel