Hi Ayan,
On 02/08/2024 13:14, Ayan Kumar Halder wrote:
> This is in continuation to commit
> f661a20aa880: "Extract MMU-specific MM code".
>
> update_identity_mapping() is defined for MMU specific logic.
> It is invoked from smpboot.c. Thus, we add an empty stub to avoid
> if-defery.
>
> Signed-off-by: Ayan Kumar Halder <ayan.kumar.halder@amd.com>
> ---
> xen/arch/arm/include/asm/arm64/mm.h | 6 ++++++
> 1 file changed, 6 insertions(+)
>
> diff --git a/xen/arch/arm/include/asm/arm64/mm.h b/xen/arch/arm/include/asm/arm64/mm.h
> index e0bd23a6ed..f595205fa3 100644
> --- a/xen/arch/arm/include/asm/arm64/mm.h
> +++ b/xen/arch/arm/include/asm/arm64/mm.h
> @@ -14,6 +14,7 @@ static inline bool arch_mfns_in_directmap(unsigned long mfn, unsigned long nr)
>
> void arch_setup_page_tables(void);
>
> +#ifdef CONFIG_MMU
> /*
> * Enable/disable the identity mapping in the live page-tables (i.e.
> * the one pointed by TTBR_EL2).
> @@ -22,6 +23,11 @@ void arch_setup_page_tables(void);
> * supported.
> */
> void update_identity_mapping(bool enable);
> +#else /* CONFIG_MMU */
> +static inline void update_identity_mapping(bool enable)
> +{
> +}
> +#endif /* CONFIG_MMU */
The name of the function reads a bit odd in the context of the MPU. How
about providing a new helper called update_boot_mapping()? For MPU, it
would still be empty (assuming this is the right approach) whereas for
the MMU it would call update_identity_mapping().
Cheers,
--
Julien Grall