Re: [Qemu-devel] [PATCH v6 07/18] kvm: add kvm_arm_get_max_vm_phys_shift
Hi Peter, On 2/14/19 6:15 PM, Peter Maydell wrote: > On Tue, 5 Feb 2019 at 17:33, 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 >> >> --- >> v4 -> v5: >> - return 40 if the host does not support the capability >> >> 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 | 10 ++ >> target/arm/kvm_arm.h | 13 + >> 2 files changed, 23 insertions(+) >> >> diff --git a/target/arm/kvm.c b/target/arm/kvm.c >> index e00ccf9c98..fc1dd3ec6a 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 +163,15 @@ 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); >> +int ret; >> + >> +ret = kvm_check_extension(s, KVM_CAP_ARM_VM_IPA_SIZE); > > Why not name the function the same as the extension name? > >> +return ret > 0 ? ret : 40; >> +} >> + >> 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..0728bbfa6b 100644 >> --- a/target/arm/kvm_arm.h >> +++ b/target/arm/kvm_arm.h >> @@ -207,6 +207,14 @@ 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 > > This is the number of bits in the IPA address space, > right (ie 40 for a 40-bit IPA, and so on) ? If so, then > I think "Return number of bits in the IPA address space" > might be clearer. It actually returns the MAX number of bits in the IPA address space supported by the host kernel. What about naming this function "kvm_arm_get_max_vm_ipa_size". Thanks Eric > >> + * >> + * @ms: Machine state handle >> + */ >> +int kvm_arm_get_max_vm_phys_shift(MachineState *ms); > > thanks > -- PMM >
Re: [Qemu-devel] [PATCH v6 07/18] kvm: add kvm_arm_get_max_vm_phys_shift
On Tue, 5 Feb 2019 at 17:33, 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 > > --- > v4 -> v5: > - return 40 if the host does not support the capability > > 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 | 10 ++ > target/arm/kvm_arm.h | 13 + > 2 files changed, 23 insertions(+) > > diff --git a/target/arm/kvm.c b/target/arm/kvm.c > index e00ccf9c98..fc1dd3ec6a 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 +163,15 @@ 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); > +int ret; > + > +ret = kvm_check_extension(s, KVM_CAP_ARM_VM_IPA_SIZE); Why not name the function the same as the extension name? > +return ret > 0 ? ret : 40; > +} > + > 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..0728bbfa6b 100644 > --- a/target/arm/kvm_arm.h > +++ b/target/arm/kvm_arm.h > @@ -207,6 +207,14 @@ 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 This is the number of bits in the IPA address space, right (ie 40 for a 40-bit IPA, and so on) ? If so, then I think "Return number of bits in the IPA address space" might be clearer. > + * > + * @ms: Machine state handle > + */ > +int kvm_arm_get_max_vm_phys_shift(MachineState *ms); thanks -- PMM
[Qemu-devel] [PATCH v6 07/18] kvm: add kvm_arm_get_max_vm_phys_shift
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 --- v4 -> v5: - return 40 if the host does not support the capability 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 | 10 ++ target/arm/kvm_arm.h | 13 + 2 files changed, 23 insertions(+) diff --git a/target/arm/kvm.c b/target/arm/kvm.c index e00ccf9c98..fc1dd3ec6a 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 +163,15 @@ 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); +int ret; + +ret = kvm_check_extension(s, KVM_CAP_ARM_VM_IPA_SIZE); +return ret > 0 ? ret : 40; +} + 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..0728bbfa6b 100644 --- a/target/arm/kvm_arm.h +++ b/target/arm/kvm_arm.h @@ -207,6 +207,14 @@ 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 + */ +int kvm_arm_get_max_vm_phys_shift(MachineState *ms); + /** * kvm_arm_sync_mpstate_to_kvm * @cpu: ARMCPU @@ -239,6 +247,11 @@ 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; -- 2.20.1