[patch RFC 04/38] x86/irq: Add allocation type for parent domain retrieval

[Thomas Gleixner <tglx@xxxxxxxxxxxxx>]

irq_remapping_ir_irq_domain() is used to retrieve the remapping parent
domain for an allocation type. irq_remapping_irq_domain() is for retrieving
the actual device domain for allocating interrupts for a device.

The two functions are similar and can be unified by using explicit modes
for parent irq domain retrieval.

Add X86_IRQ_ALLOC_TYPE_IOAPIC/HPET_GET_PARENT and use it in the iommu
implementations. Drop the parent domain retrieval for PCI_MSI/X as that is
unused.

Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Joerg Roedel <joro@xxxxxxxxxx>
Cc: x86@xxxxxxxxxx
Cc: linux-hyperv@xxxxxxxxxxxxxxx
Cc: iommu@xxxxxxxxxxxxxxxxxxxxxxxxxx
Cc: Haiyang Zhang <haiyangz@xxxxxxxxxxxxx>
Cc: Jon Derrick <jonathan.derrick@xxxxxxxxx>
Cc: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx>
---
 arch/x86/include/asm/hw_irq.h       |    2 ++
 arch/x86/kernel/apic/io_apic.c      |    2 +-
 arch/x86/kernel/apic/msi.c          |    2 +-
 drivers/iommu/amd/iommu.c           |    8 ++++++++
 drivers/iommu/hyperv-iommu.c        |    2 +-
 drivers/iommu/intel/irq_remapping.c |    8 ++------
 6 files changed, 15 insertions(+), 9 deletions(-)

--- a/arch/x86/include/asm/hw_irq.h
+++ b/arch/x86/include/asm/hw_irq.h
@@ -40,6 +40,8 @@ enum irq_alloc_type {
        X86_IRQ_ALLOC_TYPE_PCI_MSIX,
        X86_IRQ_ALLOC_TYPE_DMAR,
        X86_IRQ_ALLOC_TYPE_UV,
+       X86_IRQ_ALLOC_TYPE_IOAPIC_GET_PARENT,
+       X86_IRQ_ALLOC_TYPE_HPET_GET_PARENT,
 };
 
 struct irq_alloc_info {
--- a/arch/x86/kernel/apic/io_apic.c
+++ b/arch/x86/kernel/apic/io_apic.c
@@ -2296,7 +2296,7 @@ static int mp_irqdomain_create(int ioapi
                return 0;
 
        init_irq_alloc_info(&info, NULL);
-       info.type = X86_IRQ_ALLOC_TYPE_IOAPIC;
+       info.type = X86_IRQ_ALLOC_TYPE_IOAPIC_GET_PARENT;
        info.ioapic_id = mpc_ioapic_id(ioapic);
        parent = irq_remapping_get_ir_irq_domain(&info);
        if (!parent)
--- a/arch/x86/kernel/apic/msi.c
+++ b/arch/x86/kernel/apic/msi.c
@@ -476,7 +476,7 @@ struct irq_domain *hpet_create_irq_domai
        domain_info->data = (void *)(long)hpet_id;
 
        init_irq_alloc_info(&info, NULL);
-       info.type = X86_IRQ_ALLOC_TYPE_HPET;
+       info.type = X86_IRQ_ALLOC_TYPE_HPET_GET_PARENT;
        info.hpet_id = hpet_id;
        parent = irq_remapping_get_ir_irq_domain(&info);
        if (parent == NULL)
--- a/drivers/iommu/amd/iommu.c
+++ b/drivers/iommu/amd/iommu.c
@@ -3534,6 +3534,14 @@ static struct irq_domain *get_ir_irq_dom
        if (!info)
                return NULL;
 
+       switch (info->type) {
+       case X86_IRQ_ALLOC_TYPE_IOAPIC_GET_PARENT:
+       case X86_IRQ_ALLOC_TYPE_HPET_GET_PARENT:
+               break;
+       default:
+               return NULL;
+       }
+
        devid = get_devid(info);
        if (devid >= 0) {
                iommu = amd_iommu_rlookup_table[devid];
--- a/drivers/iommu/hyperv-iommu.c
+++ b/drivers/iommu/hyperv-iommu.c
@@ -184,7 +184,7 @@ static int __init hyperv_enable_irq_rema
 
 static struct irq_domain *hyperv_get_ir_irq_domain(struct irq_alloc_info *info)
 {
-       if (info->type == X86_IRQ_ALLOC_TYPE_IOAPIC)
+       if (info->type == X86_IRQ_ALLOC_TYPE_IOAPIC_GET_PARENT)
                return ioapic_ir_domain;
        else
                return NULL;
--- a/drivers/iommu/intel/irq_remapping.c
+++ b/drivers/iommu/intel/irq_remapping.c
@@ -1109,16 +1109,12 @@ static struct irq_domain *intel_get_ir_i
                return NULL;
 
        switch (info->type) {
-       case X86_IRQ_ALLOC_TYPE_IOAPIC:
+       case X86_IRQ_ALLOC_TYPE_IOAPIC_GET_PARENT:
                iommu = map_ioapic_to_ir(info->ioapic_id);
                break;
-       case X86_IRQ_ALLOC_TYPE_HPET:
+       case X86_IRQ_ALLOC_TYPE_HPET_GET_PARENT:
                iommu = map_hpet_to_ir(info->hpet_id);
                break;
-       case X86_IRQ_ALLOC_TYPE_PCI_MSI:
-       case X86_IRQ_ALLOC_TYPE_PCI_MSIX:
-               iommu = map_dev_to_ir(info->msi_dev);
-               break;
        default:
                BUG_ON(1);
                break;