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.au...@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;
