static int vgic_its_cmd_handle_mapi()

in kvm/vgic/vgic-its.c [1047:1107]

• 51 lines of code
• 14 McCabe index (conditional complexity)

static int vgic_its_cmd_handle_mapi(struct kvm *kvm, struct vgic_its *its,
				    u64 *its_cmd)
{
	u32 device_id = its_cmd_get_deviceid(its_cmd);
	u32 event_id = its_cmd_get_id(its_cmd);
	u32 coll_id = its_cmd_get_collection(its_cmd);
	struct its_ite *ite;
	struct kvm_vcpu *vcpu = NULL;
	struct its_device *device;
	struct its_collection *collection, *new_coll = NULL;
	struct vgic_irq *irq;
	int lpi_nr;

	device = find_its_device(its, device_id);
	if (!device)
		return E_ITS_MAPTI_UNMAPPED_DEVICE;

	if (event_id >= BIT_ULL(device->num_eventid_bits))
		return E_ITS_MAPTI_ID_OOR;

	if (its_cmd_get_command(its_cmd) == GITS_CMD_MAPTI)
		lpi_nr = its_cmd_get_physical_id(its_cmd);
	else
		lpi_nr = event_id;
	if (lpi_nr < GIC_LPI_OFFSET ||
	    lpi_nr >= max_lpis_propbaser(kvm->arch.vgic.propbaser))
		return E_ITS_MAPTI_PHYSICALID_OOR;

	/* If there is an existing mapping, behavior is UNPREDICTABLE. */
	if (find_ite(its, device_id, event_id))
		return 0;

	collection = find_collection(its, coll_id);
	if (!collection) {
		int ret = vgic_its_alloc_collection(its, &collection, coll_id);
		if (ret)
			return ret;
		new_coll = collection;
	}

	ite = vgic_its_alloc_ite(device, collection, event_id);
	if (IS_ERR(ite)) {
		if (new_coll)
			vgic_its_free_collection(its, coll_id);
		return PTR_ERR(ite);
	}

	if (its_is_collection_mapped(collection))
		vcpu = kvm_get_vcpu(kvm, collection->target_addr);

	irq = vgic_add_lpi(kvm, lpi_nr, vcpu);
	if (IS_ERR(irq)) {
		if (new_coll)
			vgic_its_free_collection(its, coll_id);
		its_free_ite(kvm, ite);
		return PTR_ERR(irq);
	}
	ite->irq = irq;

	return 0;
}