On Sat, 22 Jul 2023 03:22:47 +0100,
Raghavendra Rao Ananta <rananta@xxxxxxxxxx> 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>
> Reviewed-by: Gavin Shan <gshan@xxxxxxxxxx>
> Reviewed-by: Shaoqin Huang <shahuang@xxxxxxxxxx>
> ---
> arch/arm64/include/asm/kvm_pgtable.h | 10 ++++++++++
> arch/arm64/kvm/hyp/pgtable.c | 20 ++++++++++++++++++++
> 2 files changed, 30 insertions(+)
>
> diff --git a/arch/arm64/include/asm/kvm_pgtable.h b/arch/arm64/include/asm/kvm_pgtable.h
> index 8294a9a7e566..5e8b1ff07854 100644
> --- a/arch/arm64/include/asm/kvm_pgtable.h
> +++ b/arch/arm64/include/asm/kvm_pgtable.h
> @@ -754,4 +754,14 @@ 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 aa740a974e02..5d14d5d5819a 100644
> --- a/arch/arm64/kvm/hyp/pgtable.c
> +++ b/arch/arm64/kvm/hyp/pgtable.c
> @@ -670,6 +670,26 @@ 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;
> + }
> +}
> +
This really shouldn't live in pgtable.c. This code gets linked into
the EL2 object. What do you think happens if, for some reason, this
gets called *from EL2*?
Furthermore, this doesn't deal with page tables at all. Why isn't
mmu.c a convenient place for it, as an integral part of
kvm_arch_flush_remote_tlbs_range?
M.
--
Without deviation from the norm, progress is not possible.
