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-rw-r--r--Documentation/virtual/kvm/devices/arm-vgic.txt52
-rw-r--r--arch/arm/include/uapi/asm/kvm.h6
-rw-r--r--virt/kvm/arm/vgic.c178
3 files changed, 236 insertions, 0 deletions
diff --git a/Documentation/virtual/kvm/devices/arm-vgic.txt b/Documentation/virtual/kvm/devices/arm-vgic.txt
index c9febb2a0c3e..7f4e91b1316b 100644
--- a/Documentation/virtual/kvm/devices/arm-vgic.txt
+++ b/Documentation/virtual/kvm/devices/arm-vgic.txt
@@ -19,3 +19,55 @@ Groups:
KVM_VGIC_V2_ADDR_TYPE_CPU (rw, 64-bit)
Base address in the guest physical address space of the GIC virtual cpu
interface register mappings.
+
+ KVM_DEV_ARM_VGIC_GRP_DIST_REGS
+ Attributes:
+ The attr field of kvm_device_attr encodes two values:
+ bits: | 63 .... 40 | 39 .. 32 | 31 .... 0 |
+ values: | reserved | cpu id | offset |
+
+ All distributor regs are (rw, 32-bit)
+
+ The offset is relative to the "Distributor base address" as defined in the
+ GICv2 specs. Getting or setting such a register has the same effect as
+ reading or writing the register on the actual hardware from the cpu
+ specified with cpu id field. Note that most distributor fields are not
+ banked, but return the same value regardless of the cpu id used to access
+ the register.
+ Limitations:
+ - Priorities are not implemented, and registers are RAZ/WI
+ Errors:
+ -ENODEV: Getting or setting this register is not yet supported
+ -EBUSY: One or more VCPUs are running
+
+ KVM_DEV_ARM_VGIC_GRP_CPU_REGS
+ Attributes:
+ The attr field of kvm_device_attr encodes two values:
+ bits: | 63 .... 40 | 39 .. 32 | 31 .... 0 |
+ values: | reserved | cpu id | offset |
+
+ All CPU interface regs are (rw, 32-bit)
+
+ The offset specifies the offset from the "CPU interface base address" as
+ defined in the GICv2 specs. Getting or setting such a register has the
+ same effect as reading or writing the register on the actual hardware.
+
+ The Active Priorities Registers APRn are implementation defined, so we set a
+ fixed format for our implementation that fits with the model of a "GICv2
+ implementation without the security extensions" which we present to the
+ guest. This interface always exposes four register APR[0-3] describing the
+ maximum possible 128 preemption levels. The semantics of the register
+ indicate if any interrupts in a given preemption level are in the active
+ state by setting the corresponding bit.
+
+ Thus, preemption level X has one or more active interrupts if and only if:
+
+ APRn[X mod 32] == 0b1, where n = X / 32
+
+ Bits for undefined preemption levels are RAZ/WI.
+
+ Limitations:
+ - Priorities are not implemented, and registers are RAZ/WI
+ Errors:
+ -ENODEV: Getting or setting this register is not yet supported
+ -EBUSY: One or more VCPUs are running
diff --git a/arch/arm/include/uapi/asm/kvm.h b/arch/arm/include/uapi/asm/kvm.h
index 76a742769e2b..ef0c8785ba16 100644
--- a/arch/arm/include/uapi/asm/kvm.h
+++ b/arch/arm/include/uapi/asm/kvm.h
@@ -165,6 +165,12 @@ struct kvm_arch_memory_slot {
/* Device Control API: ARM VGIC */
#define KVM_DEV_ARM_VGIC_GRP_ADDR 0
+#define KVM_DEV_ARM_VGIC_GRP_DIST_REGS 1
+#define KVM_DEV_ARM_VGIC_GRP_CPU_REGS 2
+#define KVM_DEV_ARM_VGIC_CPUID_SHIFT 32
+#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)
/* 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 e2596f618281..88599b585362 100644
--- a/virt/kvm/arm/vgic.c
+++ b/virt/kvm/arm/vgic.c
@@ -589,6 +589,20 @@ static bool handle_mmio_sgi_reg(struct kvm_vcpu *vcpu,
return false;
}
+static bool handle_mmio_sgi_clear(struct kvm_vcpu *vcpu,
+ struct kvm_exit_mmio *mmio,
+ phys_addr_t offset)
+{
+ return false;
+}
+
+static bool handle_mmio_sgi_set(struct kvm_vcpu *vcpu,
+ struct kvm_exit_mmio *mmio,
+ phys_addr_t offset)
+{
+ return false;
+}
+
/*
* I would have liked to use the kvm_bus_io_*() API instead, but it
* cannot cope with banked registers (only the VM pointer is passed
@@ -663,6 +677,16 @@ static const struct mmio_range vgic_dist_ranges[] = {
.len = 4,
.handle_mmio = handle_mmio_sgi_reg,
},
+ {
+ .base = GIC_DIST_SGI_PENDING_CLEAR,
+ .len = VGIC_NR_SGIS,
+ .handle_mmio = handle_mmio_sgi_clear,
+ },
+ {
+ .base = GIC_DIST_SGI_PENDING_SET,
+ .len = VGIC_NR_SGIS,
+ .handle_mmio = handle_mmio_sgi_set,
+ },
{}
};
@@ -1557,6 +1581,114 @@ int kvm_vgic_addr(struct kvm *kvm, unsigned long type, u64 *addr, bool write)
return r;
}
+static bool handle_cpu_mmio_misc(struct kvm_vcpu *vcpu,
+ struct kvm_exit_mmio *mmio, phys_addr_t offset)
+{
+ return true;
+}
+
+static const struct mmio_range vgic_cpu_ranges[] = {
+ {
+ .base = GIC_CPU_CTRL,
+ .len = 12,
+ .handle_mmio = handle_cpu_mmio_misc,
+ },
+ {
+ .base = GIC_CPU_ALIAS_BINPOINT,
+ .len = 4,
+ .handle_mmio = handle_cpu_mmio_misc,
+ },
+ {
+ .base = GIC_CPU_ACTIVEPRIO,
+ .len = 16,
+ .handle_mmio = handle_cpu_mmio_misc,
+ },
+ {
+ .base = GIC_CPU_IDENT,
+ .len = 4,
+ .handle_mmio = handle_cpu_mmio_misc,
+ },
+};
+
+static int vgic_attr_regs_access(struct kvm_device *dev,
+ struct kvm_device_attr *attr,
+ u32 *reg, bool is_write)
+{
+ const struct mmio_range *r = NULL, *ranges;
+ phys_addr_t offset;
+ int ret, cpuid, c;
+ struct kvm_vcpu *vcpu, *tmp_vcpu;
+ struct vgic_dist *vgic;
+ struct kvm_exit_mmio mmio;
+
+ offset = attr->attr & KVM_DEV_ARM_VGIC_OFFSET_MASK;
+ cpuid = (attr->attr & KVM_DEV_ARM_VGIC_CPUID_MASK) >>
+ KVM_DEV_ARM_VGIC_CPUID_SHIFT;
+
+ mutex_lock(&dev->kvm->lock);
+
+ if (cpuid >= atomic_read(&dev->kvm->online_vcpus)) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ vcpu = kvm_get_vcpu(dev->kvm, cpuid);
+ vgic = &dev->kvm->arch.vgic;
+
+ mmio.len = 4;
+ mmio.is_write = is_write;
+ if (is_write)
+ mmio_data_write(&mmio, ~0, *reg);
+ switch (attr->group) {
+ case KVM_DEV_ARM_VGIC_GRP_DIST_REGS:
+ mmio.phys_addr = vgic->vgic_dist_base + offset;
+ ranges = vgic_dist_ranges;
+ break;
+ case KVM_DEV_ARM_VGIC_GRP_CPU_REGS:
+ mmio.phys_addr = vgic->vgic_cpu_base + offset;
+ ranges = vgic_cpu_ranges;
+ break;
+ default:
+ BUG();
+ }
+ r = find_matching_range(ranges, &mmio, offset);
+
+ if (unlikely(!r || !r->handle_mmio)) {
+ ret = -ENXIO;
+ goto out;
+ }
+
+
+ spin_lock(&vgic->lock);
+
+ /*
+ * Ensure that no other VCPU is running by checking the vcpu->cpu
+ * field. If no other VPCUs are running we can safely access the VGIC
+ * state, because even if another VPU is run after this point, that
+ * VCPU will not touch the vgic state, because it will block on
+ * getting the vgic->lock in kvm_vgic_sync_hwstate().
+ */
+ kvm_for_each_vcpu(c, tmp_vcpu, dev->kvm) {
+ if (unlikely(tmp_vcpu->cpu != -1)) {
+ ret = -EBUSY;
+ goto out_vgic_unlock;
+ }
+ }
+
+ offset -= r->base;
+ r->handle_mmio(vcpu, &mmio, offset);
+
+ if (!is_write)
+ *reg = mmio_data_read(&mmio, ~0);
+
+ ret = 0;
+out_vgic_unlock:
+ spin_unlock(&vgic->lock);
+out:
+ mutex_unlock(&dev->kvm->lock);
+ return ret;
+}
+
static int vgic_set_attr(struct kvm_device *dev, struct kvm_device_attr *attr)
{
int r;
@@ -1573,6 +1705,18 @@ static int vgic_set_attr(struct kvm_device *dev, struct kvm_device_attr *attr)
r = kvm_vgic_addr(dev->kvm, type, &addr, true);
return (r == -ENODEV) ? -ENXIO : r;
}
+
+ case KVM_DEV_ARM_VGIC_GRP_DIST_REGS:
+ case KVM_DEV_ARM_VGIC_GRP_CPU_REGS: {
+ u32 __user *uaddr = (u32 __user *)(long)attr->addr;
+ u32 reg;
+
+ if (get_user(reg, uaddr))
+ return -EFAULT;
+
+ return vgic_attr_regs_access(dev, attr, &reg, true);
+ }
+
}
return -ENXIO;
@@ -1594,14 +1738,42 @@ static int vgic_get_attr(struct kvm_device *dev, struct kvm_device_attr *attr)
if (copy_to_user(uaddr, &addr, sizeof(addr)))
return -EFAULT;
+ break;
+ }
+
+ case KVM_DEV_ARM_VGIC_GRP_DIST_REGS:
+ case KVM_DEV_ARM_VGIC_GRP_CPU_REGS: {
+ u32 __user *uaddr = (u32 __user *)(long)attr->addr;
+ u32 reg = 0;
+
+ r = vgic_attr_regs_access(dev, attr, &reg, false);
+ if (r)
+ return r;
+ r = put_user(reg, uaddr);
+ break;
}
+
}
return r;
}
+static int vgic_has_attr_regs(const struct mmio_range *ranges,
+ phys_addr_t offset)
+{
+ struct kvm_exit_mmio dev_attr_mmio;
+
+ dev_attr_mmio.len = 4;
+ if (find_matching_range(ranges, &dev_attr_mmio, offset))
+ return 0;
+ else
+ return -ENXIO;
+}
+
static int vgic_has_attr(struct kvm_device *dev, struct kvm_device_attr *attr)
{
+ phys_addr_t offset;
+
switch (attr->group) {
case KVM_DEV_ARM_VGIC_GRP_ADDR:
switch (attr->attr) {
@@ -1610,6 +1782,12 @@ static int vgic_has_attr(struct kvm_device *dev, struct kvm_device_attr *attr)
return 0;
}
break;
+ case KVM_DEV_ARM_VGIC_GRP_DIST_REGS:
+ offset = attr->attr & KVM_DEV_ARM_VGIC_OFFSET_MASK;
+ return vgic_has_attr_regs(vgic_dist_ranges, offset);
+ 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);
}
return -ENXIO;
}