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authorMarc Zyngier <marc.zyngier@arm.com>2014-07-08 12:09:07 +0100
committerChristoffer Dall <christoffer.dall@linaro.org>2014-10-03 20:57:07 +0200
commit9e59676711104dcafee9747b61022d81514260ed (patch)
treeeb0dc5e1adb8752ca02f04e28927b56e956edc89
parent9d4d6eba152e879d1b7e55e814a9c036d3e943a3 (diff)
downloadlinux-linaro-stable-9e59676711104dcafee9747b61022d81514260ed.tar.gz
arm/arm64: KVM: vgic: make number of irqs a configurable attribute
In order to make the number of interrupts configurable, use the new fancy device management API to add KVM_DEV_ARM_VGIC_GRP_NR_IRQS as a VGIC configurable attribute. Userspace can now specify the exact size of the GIC (by increments of 32 interrupts). Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> (cherry picked from commit a98f26f183801685ef57333de4bafd4bbc692c7c) Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
-rw-r--r--Documentation/virtual/kvm/devices/arm-vgic.txt10
-rw-r--r--arch/arm/include/uapi/asm/kvm.h1
-rw-r--r--arch/arm64/include/uapi/asm/kvm.h1
-rw-r--r--virt/kvm/arm/vgic.c37
4 files changed, 49 insertions, 0 deletions
diff --git a/Documentation/virtual/kvm/devices/arm-vgic.txt b/Documentation/virtual/kvm/devices/arm-vgic.txt
index 7f4e91b1316b..df8b0c7540b6 100644
--- a/Documentation/virtual/kvm/devices/arm-vgic.txt
+++ b/Documentation/virtual/kvm/devices/arm-vgic.txt
@@ -71,3 +71,13 @@ Groups:
Errors:
-ENODEV: Getting or setting this register is not yet supported
-EBUSY: One or more VCPUs are running
+
+ KVM_DEV_ARM_VGIC_GRP_NR_IRQS
+ Attributes:
+ A value describing the number of interrupts (SGI, PPI and SPI) for
+ this GIC instance, ranging from 64 to 1024, in increments of 32.
+
+ Errors:
+ -EINVAL: Value set is out of the expected range
+ -EBUSY: Value has already be set, or GIC has already been initialized
+ with default values.
diff --git a/arch/arm/include/uapi/asm/kvm.h b/arch/arm/include/uapi/asm/kvm.h
index 51257fda254b..09ee408c1a67 100644
--- a/arch/arm/include/uapi/asm/kvm.h
+++ b/arch/arm/include/uapi/asm/kvm.h
@@ -174,6 +174,7 @@ struct kvm_arch_memory_slot {
#define KVM_DEV_ARM_VGIC_CPUID_MASK (0xffULL << KVM_DEV_ARM_VGIC_CPUID_SHIFT)
#define KVM_DEV_ARM_VGIC_OFFSET_SHIFT 0
#define KVM_DEV_ARM_VGIC_OFFSET_MASK (0xffffffffULL << KVM_DEV_ARM_VGIC_OFFSET_SHIFT)
+#define KVM_DEV_ARM_VGIC_GRP_NR_IRQS 3
/* KVM_IRQ_LINE irq field index values */
#define KVM_ARM_IRQ_TYPE_SHIFT 24
diff --git a/arch/arm64/include/uapi/asm/kvm.h b/arch/arm64/include/uapi/asm/kvm.h
index f4ec5a674d05..8e38878c87c6 100644
--- a/arch/arm64/include/uapi/asm/kvm.h
+++ b/arch/arm64/include/uapi/asm/kvm.h
@@ -160,6 +160,7 @@ struct kvm_arch_memory_slot {
#define KVM_DEV_ARM_VGIC_CPUID_MASK (0xffULL << KVM_DEV_ARM_VGIC_CPUID_SHIFT)
#define KVM_DEV_ARM_VGIC_OFFSET_SHIFT 0
#define KVM_DEV_ARM_VGIC_OFFSET_MASK (0xffffffffULL << KVM_DEV_ARM_VGIC_OFFSET_SHIFT)
+#define KVM_DEV_ARM_VGIC_GRP_NR_IRQS 3
/* KVM_IRQ_LINE irq field index values */
#define KVM_ARM_IRQ_TYPE_SHIFT 24
diff --git a/virt/kvm/arm/vgic.c b/virt/kvm/arm/vgic.c
index dd94dbc3f7f5..a9255385a868 100644
--- a/virt/kvm/arm/vgic.c
+++ b/virt/kvm/arm/vgic.c
@@ -2253,6 +2253,36 @@ static int vgic_set_attr(struct kvm_device *dev, struct kvm_device_attr *attr)
return vgic_attr_regs_access(dev, attr, &reg, true);
}
+ case KVM_DEV_ARM_VGIC_GRP_NR_IRQS: {
+ u32 __user *uaddr = (u32 __user *)(long)attr->addr;
+ u32 val;
+ int ret = 0;
+
+ if (get_user(val, uaddr))
+ return -EFAULT;
+
+ /*
+ * We require:
+ * - at least 32 SPIs on top of the 16 SGIs and 16 PPIs
+ * - at most 1024 interrupts
+ * - a multiple of 32 interrupts
+ */
+ if (val < (VGIC_NR_PRIVATE_IRQS + 32) ||
+ val > VGIC_MAX_IRQS ||
+ (val & 31))
+ return -EINVAL;
+
+ mutex_lock(&dev->kvm->lock);
+
+ if (vgic_initialized(dev->kvm) || dev->kvm->arch.vgic.nr_irqs)
+ ret = -EBUSY;
+ else
+ dev->kvm->arch.vgic.nr_irqs = val;
+
+ mutex_unlock(&dev->kvm->lock);
+
+ return ret;
+ }
}
@@ -2289,6 +2319,11 @@ static int vgic_get_attr(struct kvm_device *dev, struct kvm_device_attr *attr)
r = put_user(reg, uaddr);
break;
}
+ case KVM_DEV_ARM_VGIC_GRP_NR_IRQS: {
+ u32 __user *uaddr = (u32 __user *)(long)attr->addr;
+ r = put_user(dev->kvm->arch.vgic.nr_irqs, uaddr);
+ break;
+ }
}
@@ -2325,6 +2360,8 @@ static int vgic_has_attr(struct kvm_device *dev, struct kvm_device_attr *attr)
case KVM_DEV_ARM_VGIC_GRP_CPU_REGS:
offset = attr->attr & KVM_DEV_ARM_VGIC_OFFSET_MASK;
return vgic_has_attr_regs(vgic_cpu_ranges, offset);
+ case KVM_DEV_ARM_VGIC_GRP_NR_IRQS:
+ return 0;
}
return -ENXIO;
}