Re: [PATCH 3/5] tools/libs/foreignmemory: Fix PAGE_SIZE redefinition error

[Julien Grall <julien@xxxxxxx>]

Hi Costin,

On 27/04/2021 13:05, Costin Lupu wrote:
>   tools/libs/foreignmemory/private.h | 6 ++++--
>   1 file changed, 4 insertions(+), 2 deletions(-)
>
> diff --git a/tools/libs/foreignmemory/private.h 
> b/tools/libs/foreignmemory/private.h
> index 1ee3626dd2..f3c1ba2867 100644
> --- a/tools/libs/foreignmemory/private.h
> +++ b/tools/libs/foreignmemory/private.h
> @@ -10,11 +10,13 @@
>   #include <xen/xen.h>
>   #include <xen/sys/privcmd.h>
>   
> -#ifndef PAGE_SHIFT /* Mini-os, Yukk */
> +#ifndef PAGE_SHIFT
>   #define PAGE_SHIFT           12
>   #endif
> -#ifndef __MINIOS__ /* Yukk */
> +#ifndef PAGE_SIZE
>   #define PAGE_SIZE            (1UL << PAGE_SHIFT)
> +#endif
> +#ifndef PAGE_MASK
>   #define PAGE_MASK            (~(PAGE_SIZE-1))
>   #endif
Looking at the usage, I believe PAGE_* are referring to the page 
granularity of Xen rather than the page granularity of the control 
domain itself.
So it would be incorrect to use the domain's page granularity here and 
would break dom0 using 64KB page granularity on Arm.
Instead, we should replace PAGE_* with XC_PAGE_*. If some of them are 
still referring to the control domain granularity, then we should use 
getpageshift() (Or equivalent) because the userspace shouldn't rely on a 
specific page granularity.
Cheers,

--
Julien Grall