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

Mario Smarduch
2014-07-25T17:37:34Z

On 07/24/2014 11:12 PM, Alexander Graf wrote:
>
> 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?

For the time being to compile ARM64.

>
>> +/**
>> + * 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.

Yes that true, I copied a generic arm/arm64 mmu function. But it's
use here guarantees kvm != NULL.

>
>
> Alex
>

Thanks,
Mario