Re: [PATCH v6 05/14] x86: Secure Launch main header file

[Simon Horman <horms@kernel.org>]

On Thu, May 04, 2023 at 02:50:14PM +0000, Ross Philipson wrote:
> Introduce the main Secure Launch header file used in the early SL stub
> and the early setup code.
> 
> Signed-off-by: Ross Philipson <ross.philipson@oracle.com>
> ---
>  include/linux/slaunch.h | 513 ++++++++++++++++++++++++++++++++++++++++++++++++
>  1 file changed, 513 insertions(+)
>  create mode 100644 include/linux/slaunch.h
> 
> diff --git a/include/linux/slaunch.h b/include/linux/slaunch.h

...

> +/* TXTCR_STS status bits */
> +#define TXT_SENTER_DONE_STS		(1<<0)
> +#define TXT_SEXIT_DONE_STS		(1<<1)

nit: Please consider using BIT()

...

> +/*
> + * External functions avalailable in mainline kernel.
> + */
> +extern void slaunch_setup_txt(void);
> +extern u32 slaunch_get_flags(void);
> +extern struct sl_ap_wake_info *slaunch_get_ap_wake_info(void);
> +extern struct acpi_table_header *slaunch_get_dmar_table(struct acpi_table_header *dmar);
> +extern void __noreturn slaunch_txt_reset(void __iomem *txt,
> +					 const char *msg, u64 error);
> +extern void slaunch_finalize(int do_sexit);

I think that extern should be avoided.
Perhaps these are in a header file that can be included?

> +
> +#endif /* !__ASSEMBLY */
> +
> +#else
> +
> +#define slaunch_setup_txt()		do { } while (0)
> +#define slaunch_get_flags()		0
> +#define slaunch_get_dmar_table(d)	(d)
> +#define slaunch_finalize(d)		do { } while (0)

I think it is usual to use static functions for this purpose.
Usually they end up in header files as static inline functions.

> +
> +#endif /* !IS_ENABLED(CONFIG_SECURE_LAUNCH) */
> +
> +#endif /* _LINUX_SLAUNCH_H */