[patch RFC 28/38] iommm/amd: Store irq domain in struct device

[Thomas Gleixner <tglx@xxxxxxxxxxxxx>]

As the next step to make X86 utilize the direct MSI irq domain operations
store the irq domain pointer in the device struct when a device is probed.

It only overrides the irqdomain of devices which are handled by a regular
PCI/MSI irq domain which protects PCI devices behind special busses like
VMD which have their own irq domain.

No functional change.

It just avoids the redirection through arch_*_msi_irqs() and allows the
PCI/MSI core to directly invoke the irq domain alloc/free functions instead
of having to look up the irq domain for every single MSI interupt.

Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Joerg Roedel <joro@xxxxxxxxxx>
Cc: iommu@xxxxxxxxxxxxxxxxxxxxxxxxxx
---
 drivers/iommu/amd/iommu.c |   17 ++++++++++++++++-
 1 file changed, 16 insertions(+), 1 deletion(-)

--- a/drivers/iommu/amd/iommu.c
+++ b/drivers/iommu/amd/iommu.c
@@ -729,7 +729,21 @@ static void iommu_poll_ga_log(struct amd
                }
        }
 }
-#endif /* CONFIG_IRQ_REMAP */
+
+static void
+amd_iommu_set_pci_msi_domain(struct device *dev, struct amd_iommu *iommu)
+{
+       if (!irq_remapping_enabled || !dev_is_pci(dev) ||
+           pci_dev_has_special_msi_domain(to_pci_dev(dev)))
+               return;
+
+       dev_set_msi_domain(dev, iommu->msi_domain);
+}
+
+#else /* CONFIG_IRQ_REMAP */
+static inline void
+amd_iommu_set_pci_msi_domain(struct device *dev, struct amd_iommu *iommu) { }
+#endif /* !CONFIG_IRQ_REMAP */
 
 #define AMD_IOMMU_INT_MASK     \
        (MMIO_STATUS_EVT_INT_MASK | \
@@ -2157,6 +2171,7 @@ static struct iommu_device *amd_iommu_pr
                iommu_dev = ERR_PTR(ret);
                iommu_ignore_device(dev);
        } else {
+               amd_iommu_set_pci_msi_domain(dev, iommu);
                iommu_dev = &iommu->iommu;
        }