Re: [PATCH v9 1/4] arm: add ARMv7 HYP API to flush VM TLBs, change generic TLB flush to support arch flush

Alexander Graf
2014-07-25T06:12:12Z

On 25.07.14 02:56, Mario Smarduch wrote:
> Patch adds HYP interface for global VM TLB invalidation without address
> parameter. Generic VM TLB flush calls ARMv7 arch defined TLB flush function.
>
> Signed-off-by: Mario Smarduch <m.smarduch@samsung.com>
> ---
> arch/arm/include/asm/kvm_asm.h | 1 +
> arch/arm/include/asm/kvm_host.h | 1 +
> arch/arm/kvm/Kconfig | 1 +
> arch/arm/kvm/interrupts.S | 12 ++++++++++++
> arch/arm/kvm/mmu.c | 17 +++++++++++++++++
> virt/kvm/Kconfig | 3 +++
> virt/kvm/kvm_main.c | 4 ++++
> 7 files changed, 39 insertions(+)
>
> diff --git a/arch/arm/include/asm/kvm_asm.h b/arch/arm/include/asm/kvm_asm.h
> index 53b3c4a..21bc519 100644
> --- a/arch/arm/include/asm/kvm_asm.h
> +++ b/arch/arm/include/asm/kvm_asm.h
> @@ -78,6 +78,7 @@ extern char __kvm_hyp_code_end[];
>
> extern void __kvm_flush_vm_context(void);
> extern void __kvm_tlb_flush_vmid_ipa(struct kvm *kvm, phys_addr_t ipa);
> +extern void __kvm_tlb_flush_vmid(struct kvm *kvm);
>
> extern int __kvm_vcpu_run(struct kvm_vcpu *vcpu);
> #endif
> diff --git a/arch/arm/include/asm/kvm_host.h b/arch/arm/include/asm/kvm_host.h
> index 193ceaf..042206f 100644
> --- a/arch/arm/include/asm/kvm_host.h
> +++ b/arch/arm/include/asm/kvm_host.h
> @@ -230,5 +230,6 @@ int kvm_perf_teardown(void);
>
> u64 kvm_arm_timer_get_reg(struct kvm_vcpu *, u64 regid);
> int kvm_arm_timer_set_reg(struct kvm_vcpu *, u64 regid, u64 value);
> +void kvm_arch_flush_remote_tlbs(struct kvm *);
>
> #endif /* __ARM_KVM_HOST_H__ */
> diff --git a/arch/arm/kvm/Kconfig b/arch/arm/kvm/Kconfig
> index 466bd29..44d3b6f 100644
> --- a/arch/arm/kvm/Kconfig
> +++ b/arch/arm/kvm/Kconfig
> @@ -22,6 +22,7 @@ config KVM
> select ANON_INODES
> select HAVE_KVM_CPU_RELAX_INTERCEPT
> select KVM_MMIO
> + select HAVE_KVM_ARCH_TLB_FLUSH_ALL
> select KVM_ARM_HOST
> depends on ARM_VIRT_EXT && ARM_LPAE
> ---help---
> diff --git a/arch/arm/kvm/interrupts.S b/arch/arm/kvm/interrupts.S
> index 0d68d40..1258d46 100644
> --- a/arch/arm/kvm/interrupts.S
> +++ b/arch/arm/kvm/interrupts.S
> @@ -66,6 +66,18 @@ ENTRY(__kvm_tlb_flush_vmid_ipa)
> bx lr
> ENDPROC(__kvm_tlb_flush_vmid_ipa)
>
> +/**
> + * void __kvm_tlb_flush_vmid(struct kvm *kvm) - Flush per-VMID TLBs
> + *
> + * Reuses __kvm_tlb_flush_vmid_ipa() for ARMv7, without passing address
> + * parameter
> + */
> +
> +ENTRY(__kvm_tlb_flush_vmid)
> + b __kvm_tlb_flush_vmid_ipa
> +ENDPROC(__kvm_tlb_flush_vmid)
> +
> +
> /********************************************************************
> * Flush TLBs and instruction caches of all CPUs inside the inner-shareable
> * domain, for all VMIDs
> diff --git a/arch/arm/kvm/mmu.c b/arch/arm/kvm/mmu.c
> index 2ac9588..35254c6 100644
> --- a/arch/arm/kvm/mmu.c
> +++ b/arch/arm/kvm/mmu.c
> @@ -56,6 +56,23 @@ static void kvm_tlb_flush_vmid_ipa(struct kvm *kvm, phys_addr_t ipa)
> kvm_call_hyp(__kvm_tlb_flush_vmid_ipa, kvm, ipa);
> }
>
> +#ifdef CONFIG_ARM

Why the ifdef? We're in ARM code here, no?

> +/**
> + * kvm_arch_flush_remote_tlbs() - flush all VM TLB entries
> + * @kvm: pointer to kvm structure.
> + *
> + * Interface to HYP function to flush all VM TLB entries without address
> + * parameter. In HYP mode reuses __kvm_tlb_flush_vmid_ipa() function used by
> + * kvm_tlb_flush_vmid_ipa().
> + */
> +void kvm_arch_flush_remote_tlbs(struct kvm *kvm)
> +{
> + if (kvm)
> + kvm_call_hyp(__kvm_tlb_flush_vmid, kvm);

I don't see why we should ever call this function with kvm==NULL.

Alex