[v5,07/18] kvm: add kvm_arm_get_max_vm_phys_shift
diff mbox series

Message ID 20190123101458.12478-8-eric.auger@redhat.com
State New
Headers show
Series
  • ARM virt: Initial RAM expansion and PCDIMM/NVDIMM support
Related show

Commit Message

Auger Eric Jan. 23, 2019, 10:14 a.m. UTC
Add the kvm_arm_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 specific IPA max size
(kvm_type passed along KVM_CREATE_VM ioctl.

Signed-off-by: Eric Auger <eric.auger@redhat.com>

---
v3 -> v4:
- s/s/ms in kvm_arm_get_max_vm_phys_shift function comment
- check KVM_CAP_ARM_VM_IPA_SIZE extension

v1 -> v2:
- put this in ARM specific code
---
 target/arm/kvm.c     |  8 ++++++++
 target/arm/kvm_arm.h | 16 ++++++++++++++++
 2 files changed, 24 insertions(+)

Comments

Jia He Jan. 29, 2019, 2:25 p.m. UTC | #1
Hi Eric

On 2019/1/23 18:14, Eric Auger wrote:
> Add the kvm_arm_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 specific IPA max size
> (kvm_type passed along KVM_CREATE_VM ioctl.
>
> Signed-off-by: Eric Auger <eric.auger@redhat.com>
>
> ---
> v3 -> v4:
> - s/s/ms in kvm_arm_get_max_vm_phys_shift function comment
> - check KVM_CAP_ARM_VM_IPA_SIZE extension
>
> v1 -> v2:
> - put this in ARM specific code
> ---
>   target/arm/kvm.c     |  8 ++++++++
>   target/arm/kvm_arm.h | 16 ++++++++++++++++
>   2 files changed, 24 insertions(+)
>
> diff --git a/target/arm/kvm.c b/target/arm/kvm.c
> index e00ccf9c98..877c588ef5 100644
> --- a/target/arm/kvm.c
> +++ b/target/arm/kvm.c
> @@ -18,6 +18,7 @@
>   #include "qemu/error-report.h"
>   #include "sysemu/sysemu.h"
>   #include "sysemu/kvm.h"
> +#include "sysemu/kvm_int.h"
>   #include "kvm_arm.h"
>   #include "cpu.h"
>   #include "trace.h"
> @@ -162,6 +163,13 @@ void kvm_arm_set_cpu_features_from_host(ARMCPU *cpu)
>       env->features = arm_host_cpu_features.features;
>   }
>   
> +int kvm_arm_get_max_vm_phys_shift(MachineState *ms)
> +{
> +    KVMState *s = KVM_STATE(ms->accelerator);
> +
> +    return kvm_check_extension(s, KVM_CAP_ARM_VM_IPA_SIZE);

If KVM_CAP_ARM_VM_IPA_SIZE is not supported in host kernel, would it be

better if kvm_arm_get_max_vm_phys_shift returns a default value

(e.g. 40),instead of an errno?

---
Cheers,
Jia He

> +}
> +
>   int kvm_arch_init(MachineState *ms, KVMState *s)
>   {
>       /* For ARM interrupt delivery is always asynchronous,
> diff --git a/target/arm/kvm_arm.h b/target/arm/kvm_arm.h
> index 6393455b1d..5969c41f83 100644
> --- a/target/arm/kvm_arm.h
> +++ b/target/arm/kvm_arm.h
> @@ -207,6 +207,17 @@ bool kvm_arm_get_host_cpu_features(ARMHostCPUFeatures *ahcf);
>    */
>   void kvm_arm_set_cpu_features_from_host(ARMCPU *cpu);
>   
> +/**
> + * kvm_arm_get_max_vm_phys_shift - Returns log2 of the max IPA size
> + * supported by KVM
> + *
> + * @ms: Machine state handle
> + *
> + * Return the max number of IPA bits or a negative value if
> + * the host kernel does not expose this value.
> + */
> +int kvm_arm_get_max_vm_phys_shift(MachineState *ms);
> +
>   /**
>    * kvm_arm_sync_mpstate_to_kvm
>    * @cpu: ARMCPU
> @@ -239,6 +250,11 @@ static inline void kvm_arm_set_cpu_features_from_host(ARMCPU *cpu)
>       cpu->host_cpu_probe_failed = true;
>   }
>   
> +static inline int kvm_arm_get_max_vm_phys_shift(MachineState *ms)
> +{
> +    return -ENOENT;
> +}
> +
>   static inline int kvm_arm_vgic_probe(void)
>   {
>       return 0;
Auger Eric Feb. 1, 2019, 10:30 a.m. UTC | #2
Hi Hia,

On 1/29/19 3:25 PM, Jia He wrote:
> Hi Eric
> 
> On 2019/1/23 18:14, Eric Auger wrote:
>> Add the kvm_arm_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 specific IPA max size
>> (kvm_type passed along KVM_CREATE_VM ioctl.
>>
>> Signed-off-by: Eric Auger <eric.auger@redhat.com>
>>
>> ---
>> v3 -> v4:
>> - s/s/ms in kvm_arm_get_max_vm_phys_shift function comment
>> - check KVM_CAP_ARM_VM_IPA_SIZE extension
>>
>> v1 -> v2:
>> - put this in ARM specific code
>> ---
>>   target/arm/kvm.c     |  8 ++++++++
>>   target/arm/kvm_arm.h | 16 ++++++++++++++++
>>   2 files changed, 24 insertions(+)
>>
>> diff --git a/target/arm/kvm.c b/target/arm/kvm.c
>> index e00ccf9c98..877c588ef5 100644
>> --- a/target/arm/kvm.c
>> +++ b/target/arm/kvm.c
>> @@ -18,6 +18,7 @@
>>   #include "qemu/error-report.h"
>>   #include "sysemu/sysemu.h"
>>   #include "sysemu/kvm.h"
>> +#include "sysemu/kvm_int.h"
>>   #include "kvm_arm.h"
>>   #include "cpu.h"
>>   #include "trace.h"
>> @@ -162,6 +163,13 @@ void kvm_arm_set_cpu_features_from_host(ARMCPU *cpu)
>>       env->features = arm_host_cpu_features.features;
>>   }
>>   +int kvm_arm_get_max_vm_phys_shift(MachineState *ms)
>> +{
>> +    KVMState *s = KVM_STATE(ms->accelerator);
>> +
>> +    return kvm_check_extension(s, KVM_CAP_ARM_VM_IPA_SIZE);
> 
> If KVM_CAP_ARM_VM_IPA_SIZE is not supported in host kernel, would it be
> 
> better if kvm_arm_get_max_vm_phys_shift returns a default value
> 
> (e.g. 40),instead of an errno?
Yes I can change that. At the moment kvm_check_extension() should return
0 if the KVM_CAP_ARM_VM_IPA_SIZE entry is not supported by the kernel.

Thanks

Eric
> 
> ---
> Cheers,
> Jia He
> 
>> +}
>> +
>>   int kvm_arch_init(MachineState *ms, KVMState *s)
>>   {
>>       /* For ARM interrupt delivery is always asynchronous,
>> diff --git a/target/arm/kvm_arm.h b/target/arm/kvm_arm.h
>> index 6393455b1d..5969c41f83 100644
>> --- a/target/arm/kvm_arm.h
>> +++ b/target/arm/kvm_arm.h
>> @@ -207,6 +207,17 @@ bool
>> kvm_arm_get_host_cpu_features(ARMHostCPUFeatures *ahcf);
>>    */
>>   void kvm_arm_set_cpu_features_from_host(ARMCPU *cpu);
>>   +/**
>> + * kvm_arm_get_max_vm_phys_shift - Returns log2 of the max IPA size
>> + * supported by KVM
>> + *
>> + * @ms: Machine state handle
>> + *
>> + * Return the max number of IPA bits or a negative value if
>> + * the host kernel does not expose this value.
>> + */
>> +int kvm_arm_get_max_vm_phys_shift(MachineState *ms);
>> +
>>   /**
>>    * kvm_arm_sync_mpstate_to_kvm
>>    * @cpu: ARMCPU
>> @@ -239,6 +250,11 @@ static inline void
>> kvm_arm_set_cpu_features_from_host(ARMCPU *cpu)
>>       cpu->host_cpu_probe_failed = true;
>>   }
>>   +static inline int kvm_arm_get_max_vm_phys_shift(MachineState *ms)
>> +{
>> +    return -ENOENT;
>> +}
>> +
>>   static inline int kvm_arm_vgic_probe(void)
>>   {
>>       return 0;
>

Patch
diff mbox series

diff --git a/target/arm/kvm.c b/target/arm/kvm.c
index e00ccf9c98..877c588ef5 100644
--- a/target/arm/kvm.c
+++ b/target/arm/kvm.c
@@ -18,6 +18,7 @@ 
 #include "qemu/error-report.h"
 #include "sysemu/sysemu.h"
 #include "sysemu/kvm.h"
+#include "sysemu/kvm_int.h"
 #include "kvm_arm.h"
 #include "cpu.h"
 #include "trace.h"
@@ -162,6 +163,13 @@  void kvm_arm_set_cpu_features_from_host(ARMCPU *cpu)
     env->features = arm_host_cpu_features.features;
 }
 
+int kvm_arm_get_max_vm_phys_shift(MachineState *ms)
+{
+    KVMState *s = KVM_STATE(ms->accelerator);
+
+    return kvm_check_extension(s, KVM_CAP_ARM_VM_IPA_SIZE);
+}
+
 int kvm_arch_init(MachineState *ms, KVMState *s)
 {
     /* For ARM interrupt delivery is always asynchronous,
diff --git a/target/arm/kvm_arm.h b/target/arm/kvm_arm.h
index 6393455b1d..5969c41f83 100644
--- a/target/arm/kvm_arm.h
+++ b/target/arm/kvm_arm.h
@@ -207,6 +207,17 @@  bool kvm_arm_get_host_cpu_features(ARMHostCPUFeatures *ahcf);
  */
 void kvm_arm_set_cpu_features_from_host(ARMCPU *cpu);
 
+/**
+ * kvm_arm_get_max_vm_phys_shift - Returns log2 of the max IPA size
+ * supported by KVM
+ *
+ * @ms: Machine state handle
+ *
+ * Return the max number of IPA bits or a negative value if
+ * the host kernel does not expose this value.
+ */
+int kvm_arm_get_max_vm_phys_shift(MachineState *ms);
+
 /**
  * kvm_arm_sync_mpstate_to_kvm
  * @cpu: ARMCPU
@@ -239,6 +250,11 @@  static inline void kvm_arm_set_cpu_features_from_host(ARMCPU *cpu)
     cpu->host_cpu_probe_failed = true;
 }
 
+static inline int kvm_arm_get_max_vm_phys_shift(MachineState *ms)
+{
+    return -ENOENT;
+}
+
 static inline int kvm_arm_vgic_probe(void)
 {
     return 0;