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

Thomas Gleixner
2020-08-21T02:20:26Z

[-- Attachment #1: x86-irq--Add-allocation-flag-for-domain-retrieval.patch --]
[-- Type: text/plain, Size: 3607 bytes --]

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@linutronix.de>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: x86@kernel.org
Cc: linux-hyperv@vger.kernel.org
Cc: iommu@lists.linux-foundation.org
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Jon Derrick <jonathan.derrick@intel.com>
Cc: Lu Baolu <baolu.lu@linux.intel.com>
---
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;