Re: [PATCH v2 32/39] xen/riscv: add minimal stuff to asm/page.h to build full Xen

[Oleksii <oleksii.kurochko@xxxxxxxxx>]

On Thu, 2023-12-14 at 16:57 +0100, Jan Beulich wrote:
> On 24.11.2023 11:30, Oleksii Kurochko wrote:
> > Signed-off-by: Oleksii Kurochko <oleksii.kurochko@xxxxxxxxx>
> 
> Acked-by: Jan Beulich <jbeulich@xxxxxxxx>
> 
> I wonder though ...
> 
> > --- a/xen/arch/riscv/include/asm/page.h
> > +++ b/xen/arch/riscv/include/asm/page.h
> > @@ -6,6 +6,7 @@
> >  #ifndef __ASSEMBLY__
> >  
> >  #include <xen/const.h>
> > +#include <xen/bug.h>
> >  #include <xen/types.h>
> >  
> >  #include <asm/mm.h>
> > @@ -32,6 +33,9 @@
> >  #define PTE_LEAF_DEFAULT            (PTE_VALID | PTE_READABLE |
> > PTE_WRITABLE)
> >  #define PTE_TABLE                   (PTE_VALID)
> >  
> > +/* TODO */
> > +#define PAGE_HYPERVISOR 0
> 
> ... whether this couldn't be defined properly right away.
It can be introduced now but it requires some additional defines to be
introduced in the same time:

#define _PAGE_W_BIT     2
#define _PAGE_XN_BIT    3
#define _PAGE_RO_BIT    1
#define _PAGE_XN        (1U << _PAGE_XN_BIT)
#define _PAGE_RO        (1U << _PAGE_RO_BIT)
#define _PAGE_W         (1U << _PAGE_W_BIT)

...
/*
 * _PAGE_DEVICE and _PAGE_NORMAL are convenience defines. They are not
 * meant to be used outside of this header.
 */
// #define _PAGE_DEVICE    _PAGE_XN
#define _PAGE_NORMAL    _PAGE_PRESENT

#define PAGE_HYPERVISOR_RW      (_PAGE_NORMAL | _PAGE_RO | _PAGE_XN |
_PAGE_W)

#define PAGE_HYPERVISOR         PAGE_HYPERVISOR_RW

And _PAGE_PRESENT in pgtbl-bits.h:

#define _PAGE_PRESENT   (1 << 0)

I prefer to introduce all this things when it will be really used.

~ Oleksii