Re: [RESEND PATCH v5 07/11] KVM: arm64: Define kvm_tlb_flush_vmid_range()

[Gavin Shan <gshan@redhat.com>]

On 6/22/23 03:49, Raghavendra Rao Ananta wrote:
> Implement the helper kvm_tlb_flush_vmid_range() that acts
> as a wrapper for range-based TLB invalidations. For the
> given VMID, use the range-based TLBI instructions to do
> the job or fallback to invalidating all the TLB entries.
> 
> Signed-off-by: Raghavendra Rao Ananta <rananta@google.com>
> ---
>   arch/arm64/include/asm/kvm_pgtable.h | 10 ++++++++++
>   arch/arm64/kvm/hyp/pgtable.c         | 20 ++++++++++++++++++++
>   2 files changed, 30 insertions(+)
> 

It may be reasonable to fold this to PATCH[08/11] since kvm_tlb_flush_vmid_range() is
only called by ARM64's kvm_arch_flush_remote_tlbs_range(), which is added by PATCH[08/11].
In either way, the changes look good to me:

Reviewed-by: Gavin Shan <gshan@redhat.com>

> diff --git a/arch/arm64/include/asm/kvm_pgtable.h b/arch/arm64/include/asm/kvm_pgtable.h
> index 4cd6762bda805..1b12295a83595 100644
> --- a/arch/arm64/include/asm/kvm_pgtable.h
> +++ b/arch/arm64/include/asm/kvm_pgtable.h
> @@ -682,4 +682,14 @@ enum kvm_pgtable_prot kvm_pgtable_stage2_pte_prot(kvm_pte_t pte);
>    *	   kvm_pgtable_prot format.
>    */
>   enum kvm_pgtable_prot kvm_pgtable_hyp_pte_prot(kvm_pte_t pte);
> +
> +/**
> + * kvm_tlb_flush_vmid_range() - Invalidate/flush a range of TLB entries
> + *
> + * @mmu:	Stage-2 KVM MMU struct
> + * @addr:	The base Intermediate physical address from which to invalidate
> + * @size:	Size of the range from the base to invalidate
> + */
> +void kvm_tlb_flush_vmid_range(struct kvm_s2_mmu *mmu,
> +				phys_addr_t addr, size_t size);
>   #endif	/* __ARM64_KVM_PGTABLE_H__ */
> diff --git a/arch/arm64/kvm/hyp/pgtable.c b/arch/arm64/kvm/hyp/pgtable.c
> index 3d61bd3e591d2..df8ac14d9d3d4 100644
> --- a/arch/arm64/kvm/hyp/pgtable.c
> +++ b/arch/arm64/kvm/hyp/pgtable.c
> @@ -631,6 +631,26 @@ static bool stage2_has_fwb(struct kvm_pgtable *pgt)
>   	return !(pgt->flags & KVM_PGTABLE_S2_NOFWB);
>   }
>   
> +void kvm_tlb_flush_vmid_range(struct kvm_s2_mmu *mmu,
> +				phys_addr_t addr, size_t size)
> +{
> +	unsigned long pages, inval_pages;
> +
> +	if (!system_supports_tlb_range()) {
> +		kvm_call_hyp(__kvm_tlb_flush_vmid, mmu);
> +		return;
> +	}
> +
> +	pages = size >> PAGE_SHIFT;
> +	while (pages > 0) {
> +		inval_pages = min(pages, MAX_TLBI_RANGE_PAGES);
> +		kvm_call_hyp(__kvm_tlb_flush_vmid_range, mmu, addr, inval_pages);
> +
> +		addr += inval_pages << PAGE_SHIFT;
> +		pages -= inval_pages;
> +	}
> +}
> +
>   #define KVM_S2_MEMATTR(pgt, attr) PAGE_S2_MEMATTR(attr, stage2_has_fwb(pgt))
>   
>   static int stage2_set_prot_attr(struct kvm_pgtable *pgt, enum kvm_pgtable_prot prot,

Thanks,
Gavin