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

[Alexander Graf <agraf@suse.de>]

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