From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([209.51.188.92]:49691) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1goUpZ-0005rz-Fw for qemu-devel@nongnu.org; Tue, 29 Jan 2019 09:57:53 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1goUgU-0000zd-7q for qemu-devel@nongnu.org; Tue, 29 Jan 2019 09:48:27 -0500 References: <20190123101458.12478-1-eric.auger@redhat.com> <20190123101458.12478-8-eric.auger@redhat.com> From: Jia He Message-ID: <85896c69-2434-ee08-331a-2216704d25e0@gmail.com> Date: Tue, 29 Jan 2019 22:25:31 +0800 MIME-Version: 1.0 In-Reply-To: <20190123101458.12478-8-eric.auger@redhat.com> Content-Type: text/plain; charset=gbk; format=flowed Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH v5 07/18] kvm: add kvm_arm_get_max_vm_phys_shift List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Eric Auger , eric.auger.pro@gmail.com, qemu-devel@nongnu.org, qemu-arm@nongnu.org, peter.maydell@linaro.org, shameerali.kolothum.thodi@huawei.com, imammedo@redhat.com, david@redhat.com Cc: drjones@redhat.com, dgilbert@redhat.com, david@gibson.dropbear.id.au 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 > > --- > 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;