[iommufd,v2,7/9] iommu/x86: Replace IOMMU_CAP_INTR_REMAP with IRQ_DOMAIN_FLAG_ISOLATED_MSI

Commit Message

Jason Gunthorpe Dec. 12, 2022, 6:46 p.m. UTC

On x86 platforms when the HW can support interrupt remapping the iommu
driver creates an irq_domain for the IR hardware and creates a child MSI
irq_domain.

When the global irq_remapping_enabled is set, the IR MSI domain is
assigned to the PCI devices (by intel_irq_remap_add_device(), or
amd_iommu_set_pci_msi_domain()) making those devices have the isolated MSI
property.

Due to how interrupt domains work, setting IRQ_DOMAIN_FLAG_ISOLATED_MSI on
the parent IR domain will cause all struct devices attached to it to
return true from msi_device_has_isolated_msi(). This replaces the
IOMMU_CAP_INTR_REMAP flag as all places using IOMMU_CAP_INTR_REMAP also
call msi_device_has_isolated_msi()

Set the flag and delete the cap.

Signed-off-by: Jason Gunthorpe <[e-mail]>
---
 drivers/iommu/amd/iommu.c           | 5 ++---
 drivers/iommu/intel/iommu.c         | 2 --
 drivers/iommu/intel/irq_remapping.c | 3 ++-
 3 files changed, 4 insertions(+), 6 deletions(-)

Patch

diff --git a/drivers/iommu/amd/iommu.c b/drivers/iommu/amd/iommu.c
index 8d37d9087fab28..3c2840cf275a60 100644
--- a/drivers/iommu/amd/iommu.c
+++ b/drivers/iommu/amd/iommu.c
@@ -2272,8 +2272,6 @@  static bool amd_iommu_capable(struct device *dev, enum iommu_cap cap)
 	switch (cap) {
 	case IOMMU_CAP_CACHE_COHERENCY:
 		return true;
-	case IOMMU_CAP_INTR_REMAP:
-		return (irq_remapping_enabled == 1);
 	case IOMMU_CAP_NOEXEC:
 		return false;
 	case IOMMU_CAP_PRE_BOOT_PROTECTION:
@@ -3672,7 +3670,8 @@  int amd_iommu_create_irq_domain(struct amd_iommu *iommu)
 	}
 
 	irq_domain_update_bus_token(iommu->ir_domain,  DOMAIN_BUS_AMDVI);
-	iommu->ir_domain->flags |= IRQ_DOMAIN_FLAG_MSI_PARENT;
+	iommu->ir_domain->flags |= IRQ_DOMAIN_FLAG_MSI_PARENT |
+				   IRQ_DOMAIN_FLAG_ISOLATED_MSI;
 
 	if (amd_iommu_np_cache)
 		iommu->ir_domain->msi_parent_ops = &virt_amdvi_msi_parent_ops;
diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c
index ebe44a07c4b00e..8037a599ade0d6 100644
--- a/drivers/iommu/intel/iommu.c
+++ b/drivers/iommu/intel/iommu.c
@@ -4453,8 +4453,6 @@  static bool intel_iommu_capable(struct device *dev, enum iommu_cap cap)
 	switch (cap) {
 	case IOMMU_CAP_CACHE_COHERENCY:
 		return true;
-	case IOMMU_CAP_INTR_REMAP:
-		return irq_remapping_enabled == 1;
 	case IOMMU_CAP_PRE_BOOT_PROTECTION:
 		return dmar_platform_optin();
 	case IOMMU_CAP_ENFORCE_CACHE_COHERENCY:
diff --git a/drivers/iommu/intel/irq_remapping.c b/drivers/iommu/intel/irq_remapping.c
index a723f53ba472f9..95d218c5077947 100644
--- a/drivers/iommu/intel/irq_remapping.c
+++ b/drivers/iommu/intel/irq_remapping.c
@@ -576,7 +576,8 @@  static int intel_setup_irq_remapping(struct intel_iommu *iommu)
 	}
 
 	irq_domain_update_bus_token(iommu->ir_domain,  DOMAIN_BUS_DMAR);
-	iommu->ir_domain->flags |= IRQ_DOMAIN_FLAG_MSI_PARENT;
+	iommu->ir_domain->flags |= IRQ_DOMAIN_FLAG_MSI_PARENT |
+				   IRQ_DOMAIN_FLAG_ISOLATED_MSI;
 
 	if (cap_caching_mode(iommu->cap))
 		iommu->ir_domain->msi_parent_ops = &virt_dmar_msi_parent_ops;