Re: [PATCH 02/10] arm64: mm: Introduce a C wrapper for by-range TLB invalidation helpers

[Ryan Roberts <ryan.roberts@arm.com>]

On 11/07/2025 17:17, Will Deacon wrote:
> In preparation for reducing our reliance on complex preprocessor macros
> for TLB invalidation routines, introduce a new C wrapper for by-range
> TLB invalidation helpers which can be used instead of the __tlbi() macro
> and can additionally be called from C code.
> 
> Signed-off-by: Will Deacon <will@kernel.org>
> ---
>  arch/arm64/include/asm/tlbflush.h | 20 +++++++++++++++++++-
>  1 file changed, 19 insertions(+), 1 deletion(-)
> 
> diff --git a/arch/arm64/include/asm/tlbflush.h b/arch/arm64/include/asm/tlbflush.h
> index 1c7548ec6cb7..4408aeebf4d5 100644
> --- a/arch/arm64/include/asm/tlbflush.h
> +++ b/arch/arm64/include/asm/tlbflush.h
> @@ -418,6 +418,24 @@ static inline void arch_tlbbatch_flush(struct arch_tlbflush_unmap_batch *batch)
>   *    operations can only span an even number of pages. We save this for last to
>   *    ensure 64KB start alignment is maintained for the LPA2 case.
>   */
> +#define __GEN_TLBI_OP_CASE(op)						\
> +	case op:							\
> +		__tlbi(r ## op, arg);					\
> +		break
> +
> +static __always_inline void __tlbi_range(const enum tlbi_op op, u64 arg)

nit: you called the level version __tlbi_level_op(). Why not call this
__tlbi_range_op() for consistency?

> +{
> +	switch (op) {
> +	__GEN_TLBI_OP_CASE(vae1is);
> +	__GEN_TLBI_OP_CASE(vale1is);
> +	__GEN_TLBI_OP_CASE(vaale1is);
> +	__GEN_TLBI_OP_CASE(ipas2e1is);
> +	default:
> +		BUILD_BUG();
> +	}
> +}
> +#undef __GEN_TLBI_OP_CASE
> +
>  #define __flush_tlb_range_op(op, start, pages, stride,			\
>  				asid, tlb_level, tlbi_user, lpa2)	\
>  do {									\
> @@ -445,7 +463,7 @@ do {									\
>  		if (num >= 0) {						\
>  			addr = __TLBI_VADDR_RANGE(__flush_start >> shift, asid, \
>  						scale, num, tlb_level);	\
> -			__tlbi(r##op, addr);				\
> +			__tlbi_range(op, addr);				\
>  			if (tlbi_user)					\
>  				__tlbi_user(r##op, addr);		\
>  			__flush_start += __TLBI_RANGE_PAGES(num, scale) << PAGE_SHIFT; \