iommu/amd: Consolidate irq domain getter

The irq domain request mode is now indicated in irq_alloc_info::type.

Consolidate the two getter functions into one.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Joerg Roedel <jroedel@suse.de>
Link: https://lore.kernel.org/r/20200826112331.634777249@linutronix.de

drivers/iommu/amd/iommu.c

@@ -3519,77 +3519,54 @@ static void irte_ga_clear_allocated(struct irq_remap_table *table, int index)
 
 static int get_devid(struct irq_alloc_info *info)
 {
-	int devid = -1;
-
 	switch (info->type) {
 	case X86_IRQ_ALLOC_TYPE_IOAPIC:
-		devid     = get_ioapic_devid(info->ioapic_id);
-		break;
+	case X86_IRQ_ALLOC_TYPE_IOAPIC_GET_PARENT:
+		return get_ioapic_devid(info->ioapic_id);
 	case X86_IRQ_ALLOC_TYPE_HPET:
-		devid     = get_hpet_devid(info->hpet_id);
-		break;
+	case X86_IRQ_ALLOC_TYPE_HPET_GET_PARENT:
+		return get_hpet_devid(info->hpet_id);
 	case X86_IRQ_ALLOC_TYPE_PCI_MSI:
 	case X86_IRQ_ALLOC_TYPE_PCI_MSIX:
-		devid = get_device_id(&info->msi_dev->dev);
-		break;
+		return get_device_id(&info->msi_dev->dev);
 	default:
-		BUG_ON(1);
-		break;
+		WARN_ON_ONCE(1);
+		return -1;
 	}
-
-	return devid;
 }
 
-static struct irq_domain *get_ir_irq_domain(struct irq_alloc_info *info)
+static struct irq_domain *get_irq_domain_for_devid(struct irq_alloc_info *info,
+						   int devid)
 {
-	struct amd_iommu *iommu;
-	int devid;
+	struct amd_iommu *iommu = amd_iommu_rlookup_table[devid];
 
-	if (!info)
+	if (!iommu)
 		return NULL;
 
 	switch (info->type) {
 	case X86_IRQ_ALLOC_TYPE_IOAPIC_GET_PARENT:
 	case X86_IRQ_ALLOC_TYPE_HPET_GET_PARENT:
-		break;
+		return iommu->ir_domain;
+	case X86_IRQ_ALLOC_TYPE_PCI_MSI:
+	case X86_IRQ_ALLOC_TYPE_PCI_MSIX:
+		return iommu->msi_domain;
 	default:
+		WARN_ON_ONCE(1);
 		return NULL;
 	}
-
-	devid = get_devid(info);
-	if (devid >= 0) {
-		iommu = amd_iommu_rlookup_table[devid];
-		if (iommu)
-			return iommu->ir_domain;
-	}
-
-	return NULL;
 }
 
 static struct irq_domain *get_irq_domain(struct irq_alloc_info *info)
 {
-	struct amd_iommu *iommu;
 	int devid;
 
 	if (!info)
 		return NULL;
 
-	switch (info->type) {
-	case X86_IRQ_ALLOC_TYPE_PCI_MSI:
-	case X86_IRQ_ALLOC_TYPE_PCI_MSIX:
-		devid = get_device_id(&info->msi_dev->dev);
-		if (devid < 0)
-			return NULL;
-
-		iommu = amd_iommu_rlookup_table[devid];
-		if (iommu)
-			return iommu->msi_domain;
-		break;
-	default:
-		break;
-	}
-
-	return NULL;
+	devid = get_devid(info);
+	if (devid < 0)
+		return NULL;
+	return get_irq_domain_for_devid(info, devid);
 }
 
 struct irq_remap_ops amd_iommu_irq_ops = {
@@ -3598,7 +3575,7 @@ struct irq_remap_ops amd_iommu_irq_ops = {
 	.disable		= amd_iommu_disable,
 	.reenable		= amd_iommu_reenable,
 	.enable_faulting	= amd_iommu_enable_faulting,
-	.get_ir_irq_domain	= get_ir_irq_domain,
+	.get_ir_irq_domain	= get_irq_domain,
 	.get_irq_domain		= get_irq_domain,
 };