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

[Raghavendra Rao Ananta]

Hi Gavin,

On Wed, Jul 5, 2023 at 5:04 PM Gavin Shan <gshan@xxxxxxxxxx> wrote:
>
> On 7/6/23 04:28, Raghavendra Rao Ananta wrote:
> > On Tue, Jul 4, 2023 at 5:31 PM Gavin Shan <gshan@xxxxxxxxxx> wrote:
> >> 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@xxxxxxxxxx>
> >>> ---
> >>>    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:
> >>
> > Ah, the patches 10 and 11 also call kvm_tlb_flush_vmid_range(), so
> > probably it's better to keep the definition isolated?
> >
>
> Thanks for your explanation. It's fine to have two separate patches in this
> case. I still need to spend some time to look at PATCH[11/11] whose subject
> includes typo (intructions -> instructions)
>
I'm planning to send v6 soon, but I'm happy to wait if you have any
other comments on v5 patch-11.
Appreciate your help with the reviews.

Thank you.
Raghavendra
> Thanks,
> Gavin
>
> >> Reviewed-by: Gavin Shan <gshan@xxxxxxxxxx>
> >>
> >>> 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,
>