From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:38784) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1fVghT-0005QF-JR for qemu-devel@nongnu.org; Wed, 20 Jun 2018 13:15:22 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1fVghP-0003rB-Bk for qemu-devel@nongnu.org; Wed, 20 Jun 2018 13:15:19 -0400 Date: Wed, 20 Jun 2018 18:15:05 +0100 From: "Dr. David Alan Gilbert" Message-ID: <20180620171504.GR2549@work-vm> References: <1529500053-21704-1-git-send-email-eric.auger@redhat.com> <1529500053-21704-6-git-send-email-eric.auger@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1529500053-21704-6-git-send-email-eric.auger@redhat.com> Subject: Re: [Qemu-devel] [RFC 5/6] hw/arm/virt: support kvm_type property List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Eric Auger Cc: eric.auger.pro@gmail.com, qemu-devel@nongnu.org, qemu-arm@nongnu.org, peter.maydell@linaro.org, agraf@suse.de, david@gibson.dropbear.id.au, drjones@redhat.com, wei@redhat.com, suzuki.poulose@arm.com * Eric Auger (eric.auger@redhat.com) wrote: > The kvm-type property currently is used to pass > a user parameter to KVM_CREATE_VM. This matches > the way KVM/ARM expects to pass the max_vm_phys_shift > parameter. > > This patch adds the support or the kvm-type property in > machvirt and also implements the machine class kvm_type() > callback so that it either returns the kvm-type value > provided by the user or returns the max_vm_phys_shift > exposed by KVM. > > for instance, the usespace can use the following option to > instantiate a 42b IPA guest: -machine kvm-type=42 Without saying if this is better or worse, it is different from x86, where we have the number of physical address bits as a -cpu parameter rather than a machine parameter, e.g. qemu-system-x86_64 -M pc,accel=kvm -cpu SandyBridge,phys-bits=36 or qemu-system-x86_64 -M pc,accel=kvm -cpu SandyBridge,host-phys-bits=true our machine types can override the default value though. One other complication (that I don't know if it applies to ARM) is that TCG only supports phys-bits=40, so we refuse a TCG run with an explicitly set phys-bits!=40. Dave > Signed-off-by: Eric Auger > --- > hw/arm/virt.c | 44 ++++++++++++++++++++++++++++++++++++++++++++ > include/hw/arm/virt.h | 1 + > 2 files changed, 45 insertions(+) > > diff --git a/hw/arm/virt.c b/hw/arm/virt.c > index dd92ab9..1700556 100644 > --- a/hw/arm/virt.c > +++ b/hw/arm/virt.c > @@ -1585,6 +1585,21 @@ static void virt_set_iommu(Object *obj, const char *value, Error **errp) > } > } > > +static char *virt_get_kvm_type(Object *obj, Error **errp) > +{ > + VirtMachineState *vms = VIRT_MACHINE(obj); > + > + return g_strdup(vms->kvm_type); > +} > + > +static void virt_set_kvm_type(Object *obj, const char *value, Error **errp) > +{ > + VirtMachineState *vms = VIRT_MACHINE(obj); > + > + g_free(vms->kvm_type); > + vms->kvm_type = g_strdup(value); > +} > + > static CpuInstanceProperties > virt_cpu_index_to_props(MachineState *ms, unsigned cpu_index) > { > @@ -1646,6 +1661,31 @@ static HotplugHandler *virt_machine_get_hotplug_handler(MachineState *machine, > return NULL; > } > > +static int virt_kvm_type(MachineState *ms, const char *type_str) > +{ > + int max_vm_phys_shift, ret = 0; > + uint64_t type; > + > + if (!type_str) { > + max_vm_phys_shift = kvm_get_max_vm_phys_shift(ms); > + if (max_vm_phys_shift < 0) { > + goto out; > + } > + } else { > + type = g_ascii_strtoll(type_str, NULL, 0); > + type &= 0xFF; > + max_vm_phys_shift = (int)type; > + if (max_vm_phys_shift < 40 || max_vm_phys_shift > 52) { > + warn_report("valid kvm-type type values are within [40, 52]:" > + " option is ignored and VM is created with 40b IPA"); > + goto out; > + } > + } > + ret = max_vm_phys_shift; > +out: > + return ret; > +} > + > static void virt_machine_class_init(ObjectClass *oc, void *data) > { > MachineClass *mc = MACHINE_CLASS(oc); > @@ -1668,6 +1708,7 @@ static void virt_machine_class_init(ObjectClass *oc, void *data) > mc->cpu_index_to_instance_props = virt_cpu_index_to_props; > mc->default_cpu_type = ARM_CPU_TYPE_NAME("cortex-a15"); > mc->get_default_cpu_node_id = virt_get_default_cpu_node_id; > + mc->kvm_type = virt_kvm_type; > assert(!mc->get_hotplug_handler); > mc->get_hotplug_handler = virt_machine_get_hotplug_handler; > hc->plug = virt_machine_device_plug_cb; > @@ -1756,6 +1797,9 @@ static void virt_3_0_instance_init(Object *obj) > "Valid values are none and smmuv3", > NULL); > > + object_property_add_str(obj, "kvm-type", > + virt_get_kvm_type, virt_set_kvm_type, NULL); > + > vms->memmap = a15memmap; > vms->irqmap = a15irqmap; > } > diff --git a/include/hw/arm/virt.h b/include/hw/arm/virt.h > index 4ac7ef6..2674ce7 100644 > --- a/include/hw/arm/virt.h > +++ b/include/hw/arm/virt.h > @@ -118,6 +118,7 @@ typedef struct { > uint32_t msi_phandle; > uint32_t iommu_phandle; > int psci_conduit; > + char *kvm_type; > } VirtMachineState; > > #define TYPE_VIRT_MACHINE MACHINE_TYPE_NAME("virt") > -- > 2.5.5 > -- Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK