KVM: arm/arm64: Replace the single rdist region by a list

At the moment KVM supports a single rdist region. We want to
support several separate rdist regions so let's introduce a list
of them. This patch currently only cares about a single
entry in this list as the functionality to register several redist
regions is not yet there. So this only translates the existing code
into something functionally similar using that new data struct.

The redistributor region handle is stored in the vgic_cpu structure
to allow later computation of the TYPER last bit.

Signed-off-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Christoffer Dall <christoffer.dall@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

1 files changed, 30 insertions, 8 deletions

diff --git a/virt/kvm/arm/vgic/vgic-mmio-v3.c b/virt/kvm/arm/vgic/vgic-mmio-v3.c
index 671fe81f8e1d..d1aab183a1cc 100644
--- a/virt/kvm/arm/vgic/vgic-mmio-v3.c
+++ b/virt/kvm/arm/vgic/vgic-mmio-v3.c
@@ -580,8 +580,10 @@ int vgic_register_redist_iodev(struct kvm_vcpu *vcpu)
 {
 	struct kvm *kvm = vcpu->kvm;
 	struct vgic_dist *vgic = &kvm->arch.vgic;
+	struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu;
 	struct vgic_io_device *rd_dev = &vcpu->arch.vgic_cpu.rd_iodev;
 	struct vgic_io_device *sgi_dev = &vcpu->arch.vgic_cpu.sgi_iodev;
+	struct vgic_redist_region *rdreg;
 	gpa_t rd_base, sgi_base;
 	int ret;
 
@@ -591,13 +593,17 @@ int vgic_register_redist_iodev(struct kvm_vcpu *vcpu)
 	 * function for all VCPUs when the base address is set.  Just return
 	 * without doing any work for now.
 	 */
-	if (IS_VGIC_ADDR_UNDEF(vgic->vgic_redist_base))
+	rdreg = list_first_entry(&vgic->rd_regions,
+				 struct vgic_redist_region, list);
+	if (!rdreg)
 		return 0;
 
 	if (!vgic_v3_check_base(kvm))
 		return -EINVAL;
 
-	rd_base = vgic->vgic_redist_base + vgic->vgic_redist_free_offset;
+	vgic_cpu->rdreg = rdreg;
+
+	rd_base = rdreg->base + rdreg->free_index * KVM_VGIC_V3_REDIST_SIZE;
 	sgi_base = rd_base + SZ_64K;
 
 	kvm_iodevice_init(&rd_dev->dev, &kvm_io_gic_ops);
@@ -631,7 +637,7 @@ int vgic_register_redist_iodev(struct kvm_vcpu *vcpu)
 		goto out;
 	}
 
-	vgic->vgic_redist_free_offset += 2 * SZ_64K;
+	rdreg->free_index++;
 out:
 	mutex_unlock(&kvm->slots_lock);
 	return ret;
@@ -673,19 +679,31 @@ static int vgic_register_all_redist_iodevs(struct kvm *kvm)
 int vgic_v3_set_redist_base(struct kvm *kvm, u64 addr)
 {
 	struct vgic_dist *vgic = &kvm->arch.vgic;
+	struct vgic_redist_region *rdreg;
 	int ret;
 
 	/* vgic_check_ioaddr makes sure we don't do this twice */
-	ret = vgic_check_ioaddr(kvm, &vgic->vgic_redist_base, addr, SZ_64K);
+	if (!list_empty(&vgic->rd_regions))
+		return -EINVAL;
+
+	rdreg = kzalloc(sizeof(*rdreg), GFP_KERNEL);
+	if (!rdreg)
+		return -ENOMEM;
+
+	rdreg->base = VGIC_ADDR_UNDEF;
+
+	ret = vgic_check_ioaddr(kvm, &rdreg->base, addr, SZ_64K);
 	if (ret)
-		return ret;
+		goto out;
 
-	vgic->vgic_redist_base = addr;
+	rdreg->base = addr;
 	if (!vgic_v3_check_base(kvm)) {
-		vgic->vgic_redist_base = VGIC_ADDR_UNDEF;
-		return -EINVAL;
+		ret = -EINVAL;
+		goto out;
 	}
 
+	list_add(&rdreg->list, &vgic->rd_regions);
+
 	/*
 	 * Register iodevs for each existing VCPU.  Adding more VCPUs
 	 * afterwards will register the iodevs when needed.
@@ -695,6 +713,10 @@ int vgic_v3_set_redist_base(struct kvm *kvm, u64 addr)
 		return ret;
 
 	return 0;
+
+out:
+	kfree(rdreg);
+	return ret;
 }
 
 int vgic_v3_has_attr_regs(struct kvm_device *dev, struct kvm_device_attr *attr)