[PATCH 3/8] KVM: arm/arm64: Refactor vgic_register_redist_iodevs

[Christoffer Dall]

Split out the function to register all the redistributor iodevs into a
function that handles a single redistributor at a time in preparation
for being able to call this per VCPU as these get created.

Signed-off-by: Christoffer Dall <cdall at linaro.org>
---
 virt/kvm/arm/vgic/vgic-mmio-v3.c | 108 ++++++++++++++++++++++++---------------
 virt/kvm/arm/vgic/vgic-v3.c      |   2 +-
 virt/kvm/arm/vgic/vgic.h         |   2 +-
 3 files changed, 68 insertions(+), 44 deletions(-)

diff --git a/virt/kvm/arm/vgic/vgic-mmio-v3.c b/virt/kvm/arm/vgic/vgic-mmio-v3.c
index 6afb3b4..1828ac7 100644
--- a/virt/kvm/arm/vgic/vgic-mmio-v3.c
+++ b/virt/kvm/arm/vgic/vgic-mmio-v3.c
@@ -556,61 +556,85 @@ unsigned int vgic_v3_init_dist_iodev(struct vgic_io_device *dev)
 	return SZ_64K;
 }
 
-int vgic_register_redist_iodevs(struct kvm *kvm, gpa_t redist_base_address)
+/**
+ * vgic_register_redist_iodev - register a single redist iodev
+ * @vcpu:    The VCPU to which the redistributor belongs
+ *
+ * Register a KVM iodev for this VCPU's redistributor using the address
+ * provided.
+ *
+ * Return 0 on success, -ERRNO otherwise.
+ */
+static int vgic_register_redist_iodev(struct kvm_vcpu *vcpu)
+{
+	struct kvm *kvm = vcpu->kvm;
+	struct vgic_dist *vgic = &kvm->arch.vgic;
+	struct vgic_io_device *rd_dev = &vcpu->arch.vgic_cpu.rd_iodev;
+	struct vgic_io_device *sgi_dev = &vcpu->arch.vgic_cpu.sgi_iodev;
+	gpa_t rd_base, sgi_base;
+	int ret;
+
+	rd_base = vgic->vgic_redist_base + vcpu->vcpu_id * SZ_64K * 2;
+	sgi_base = rd_base + SZ_64K;
+
+	kvm_iodevice_init(&rd_dev->dev, &kvm_io_gic_ops);
+	rd_dev->base_addr = rd_base;
+	rd_dev->iodev_type = IODEV_REDIST;
+	rd_dev->regions = vgic_v3_rdbase_registers;
+	rd_dev->nr_regions = ARRAY_SIZE(vgic_v3_rdbase_registers);
+	rd_dev->redist_vcpu = vcpu;
+
+	mutex_lock(&kvm->slots_lock);
+	ret = kvm_io_bus_register_dev(kvm, KVM_MMIO_BUS, rd_base,
+				      SZ_64K, &rd_dev->dev);
+	mutex_unlock(&kvm->slots_lock);
+
+	if (ret)
+		return ret;
+
+	kvm_iodevice_init(&sgi_dev->dev, &kvm_io_gic_ops);
+	sgi_dev->base_addr = sgi_base;
+	sgi_dev->iodev_type = IODEV_REDIST;
+	sgi_dev->regions = vgic_v3_sgibase_registers;
+	sgi_dev->nr_regions = ARRAY_SIZE(vgic_v3_sgibase_registers);
+	sgi_dev->redist_vcpu = vcpu;
+
+	mutex_lock(&kvm->slots_lock);
+	ret = kvm_io_bus_register_dev(kvm, KVM_MMIO_BUS, sgi_base,
+				      SZ_64K, &sgi_dev->dev);
+	mutex_unlock(&kvm->slots_lock);
+	if (ret)
+		kvm_io_bus_unregister_dev(kvm, KVM_MMIO_BUS,
+					  &rd_dev->dev);
+
+	return ret;
+}
+
+static void vgic_unregister_redist_iodev(struct kvm_vcpu *vcpu)
+{
+	struct vgic_io_device *rd_dev = &vcpu->arch.vgic_cpu.rd_iodev;
+	struct vgic_io_device *sgi_dev = &vcpu->arch.vgic_cpu.sgi_iodev;
+
+	kvm_io_bus_unregister_dev(vcpu->kvm, KVM_MMIO_BUS, &rd_dev->dev);
+	kvm_io_bus_unregister_dev(vcpu->kvm, KVM_MMIO_BUS, &sgi_dev->dev);
+}
+
+int vgic_register_redist_iodevs(struct kvm *kvm)
 {
 	struct kvm_vcpu *vcpu;
 	int c, ret = 0;
 
 	kvm_for_each_vcpu(c, vcpu, kvm) {
-		gpa_t rd_base = redist_base_address + c * SZ_64K * 2;
-		gpa_t sgi_base = rd_base + SZ_64K;
-		struct vgic_io_device *rd_dev = &vcpu->arch.vgic_cpu.rd_iodev;
-		struct vgic_io_device *sgi_dev = &vcpu->arch.vgic_cpu.sgi_iodev;
-
-		kvm_iodevice_init(&rd_dev->dev, &kvm_io_gic_ops);
-		rd_dev->base_addr = rd_base;
-		rd_dev->iodev_type = IODEV_REDIST;
-		rd_dev->regions = vgic_v3_rdbase_registers;
-		rd_dev->nr_regions = ARRAY_SIZE(vgic_v3_rdbase_registers);
-		rd_dev->redist_vcpu = vcpu;
-
-		mutex_lock(&kvm->slots_lock);
-		ret = kvm_io_bus_register_dev(kvm, KVM_MMIO_BUS, rd_base,
-					      SZ_64K, &rd_dev->dev);
-		mutex_unlock(&kvm->slots_lock);
-
+		ret = vgic_register_redist_iodev(vcpu);
 		if (ret)
 			break;
-
-		kvm_iodevice_init(&sgi_dev->dev, &kvm_io_gic_ops);
-		sgi_dev->base_addr = sgi_base;
-		sgi_dev->iodev_type = IODEV_REDIST;
-		sgi_dev->regions = vgic_v3_sgibase_registers;
-		sgi_dev->nr_regions = ARRAY_SIZE(vgic_v3_sgibase_registers);
-		sgi_dev->redist_vcpu = vcpu;
-
-		mutex_lock(&kvm->slots_lock);
-		ret = kvm_io_bus_register_dev(kvm, KVM_MMIO_BUS, sgi_base,
-					      SZ_64K, &sgi_dev->dev);
-		mutex_unlock(&kvm->slots_lock);
-		if (ret) {
-			kvm_io_bus_unregister_dev(kvm, KVM_MMIO_BUS,
-						  &rd_dev->dev);
-			break;
-		}
 	}
 
 	if (ret) {
 		/* The current c failed, so we start with the previous one. */
 		for (c--; c >= 0; c--) {
-			struct vgic_cpu *vgic_cpu;
-
 			vcpu = kvm_get_vcpu(kvm, c);
-			vgic_cpu = &vcpu->arch.vgic_cpu;
-			kvm_io_bus_unregister_dev(kvm, KVM_MMIO_BUS,
-						  &vgic_cpu->rd_iodev.dev);
-			kvm_io_bus_unregister_dev(kvm, KVM_MMIO_BUS,
-						  &vgic_cpu->sgi_iodev.dev);
+			vgic_unregister_redist_iodev(vcpu);
 		}
 	}
 
diff --git a/virt/kvm/arm/vgic/vgic-v3.c b/virt/kvm/arm/vgic/vgic-v3.c
index 54dee72..12e52a0 100644
--- a/virt/kvm/arm/vgic/vgic-v3.c
+++ b/virt/kvm/arm/vgic/vgic-v3.c
@@ -386,7 +386,7 @@ int vgic_v3_map_resources(struct kvm *kvm)
 		goto out;
 	}
 
-	ret = vgic_register_redist_iodevs(kvm, dist->vgic_redist_base);
+	ret = vgic_register_redist_iodevs(kvm);
 	if (ret) {
 		kvm_err("Unable to register VGICv3 redist MMIO regions\n");
 		goto out;
diff --git a/virt/kvm/arm/vgic/vgic.h b/virt/kvm/arm/vgic/vgic.h
index 8259f0a..a2aeaa8 100644
--- a/virt/kvm/arm/vgic/vgic.h
+++ b/virt/kvm/arm/vgic/vgic.h
@@ -174,7 +174,7 @@ int vgic_v3_probe(const struct gic_kvm_info *info);
 int vgic_v3_map_resources(struct kvm *kvm);
 int vgic_v3_lpi_sync_pending_status(struct kvm *kvm, struct vgic_irq *irq);
 int vgic_v3_save_pending_tables(struct kvm *kvm);
-int vgic_register_redist_iodevs(struct kvm *kvm, gpa_t dist_base_address);
+int vgic_register_redist_iodevs(struct kvm *kvm);
 
 void vgic_v3_load(struct kvm_vcpu *vcpu);
 void vgic_v3_put(struct kvm_vcpu *vcpu);
-- 
2.9.0