Re: [Qemu-devel] [RFC 3/6] kvm: add kvm_get_max_vm_phys_shift

[Auger Eric <eric.auger@redhat.com>]

Hi David,

On 06/21/2018 02:37 AM, David Gibson wrote:
> On Wed, Jun 20, 2018 at 03:07:30PM +0200, Eric Auger wrote:
>> Add the kvm_get_max_vm_phys_shift() helper that returns the
>> log of the maximum IPA size supported by KVM. This capability
>> needs to be known to create the VM with a correct IPA max size
>> (kvm_type passed along KVM_CREATE_VM ioctl.
>>
>> Signed-off-by: Eric Auger <eric.auger@redhat.com>
>> ---
>>  accel/kvm/kvm-all.c    | 7 +++++++
>>  accel/stubs/kvm-stub.c | 5 +++++
>>  include/sysemu/kvm.h   | 1 +
>>  3 files changed, 13 insertions(+)
>>
>> diff --git a/accel/kvm/kvm-all.c b/accel/kvm/kvm-all.c
>> index 0590986..137c38e 100644
>> --- a/accel/kvm/kvm-all.c
>> +++ b/accel/kvm/kvm-all.c
>> @@ -280,6 +280,13 @@ static int kvm_set_user_memory_region(KVMMemoryListener *kml, KVMSlot *slot)
>>      return ret;
>>  }
>>  
>> +int kvm_get_max_vm_phys_shift(MachineState *ms)
>> +{
>> +    KVMState *s = KVM_STATE(ms->accelerator);
>> +
>> +    return kvm_ioctl(s, KVM_ARM_GET_MAX_VM_PHYS_SHIFT, 0);
> 
> From the ioctl() name, I'm assuming this is an ARM specific call.
> 
> In which case, shouldn't it be in target/arm.kvm.c, not kvm-all.c ?
Yes definitively.

Thanks

Eric
> 
>> +}
>> +
>>  int kvm_destroy_vcpu(CPUState *cpu)
>>  {
>>      KVMState *s = kvm_state;
>> diff --git a/accel/stubs/kvm-stub.c b/accel/stubs/kvm-stub.c
>> index 02d5170..7575ba7 100644
>> --- a/accel/stubs/kvm-stub.c
>> +++ b/accel/stubs/kvm-stub.c
>> @@ -161,6 +161,11 @@ bool kvm_has_free_slot(MachineState *ms)
>>      return false;
>>  }
>>  
>> +int kvm_get_max_vm_phys_shift(MachineState *ms)
>> +{
>> +    return 0;
>> +}
>> +
>>  void kvm_init_cpu_signals(CPUState *cpu)
>>  {
>>      abort();
>> diff --git a/include/sysemu/kvm.h b/include/sysemu/kvm.h
>> index 0b64b8e..240e3d9 100644
>> --- a/include/sysemu/kvm.h
>> +++ b/include/sysemu/kvm.h
>> @@ -206,6 +206,7 @@ extern KVMState *kvm_state;
>>  /* external API */
>>  
>>  bool kvm_has_free_slot(MachineState *ms);
>> +int kvm_get_max_vm_phys_shift(MachineState *ms);
>>  bool kvm_has_sync_mmu(void);
>>  int kvm_has_vcpu_events(void);
>>  int kvm_has_robust_singlestep(void);
>