iommu/vt-d: Allocate domain info for real DMA sub-devices

Sub-devices of a real DMA device might exist on a separate segment than
the real DMA device and its IOMMU. These devices should still have a
valid device_domain_info, but the current dma alias model won't
allocate info for the subdevice.

This patch adds a segment member to struct device_domain_info and uses
the sub-device's BDF so that these sub-devices won't alias to other
devices.

Fixes: 2b0140c69637e ("iommu/vt-d: Use pci_real_dma_dev() for mapping")
Cc: stable@vger.kernel.org # v5.6+
Signed-off-by: Jon Derrick <jonathan.derrick@intel.com>
Acked-by: Lu Baolu <baolu.lu@linux.intel.com>
Link: https://lore.kernel.org/r/20200527165617.297470-3-jonathan.derrick@intel.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>

diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c
index 1ff45b2..6d39b9b 100644 (file)
--- a/drivers/iommu/intel-iommu.c
+++ b/drivers/iommu/intel-iommu.c
@@ -2463,7 +2463,7 @@ dmar_search_domain_by_dev_info(int segment, int bus, int devfn)
        struct device_domain_info *info;
 
        list_for_each_entry(info, &device_domain_list, global)
-               if (info->iommu->segment == segment && info->bus == bus &&
+               if (info->segment == segment && info->bus == bus &&
                    info->devfn == devfn)
                        return info;
 
@@ -2520,8 +2520,18 @@ static struct dmar_domain *dmar_insert_one_dev_info(struct intel_iommu *iommu,
        if (!info)
                return NULL;
 
-       info->bus = bus;
-       info->devfn = devfn;
+       if (!dev_is_real_dma_subdevice(dev)) {
+               info->bus = bus;
+               info->devfn = devfn;
+               info->segment = iommu->segment;
+       } else {
+               struct pci_dev *pdev = to_pci_dev(dev);
+
+               info->bus = pdev->bus->number;
+               info->devfn = pdev->devfn;
+               info->segment = pci_domain_nr(pdev->bus);
+       }
+
        info->ats_supported = info->pasid_supported = info->pri_supported = 0;
        info->ats_enabled = info->pasid_enabled = info->pri_enabled = 0;
        info->ats_qdep = 0;
@@ -2561,7 +2571,8 @@ static struct dmar_domain *dmar_insert_one_dev_info(struct intel_iommu *iommu,
 
        if (!found) {
                struct device_domain_info *info2;
-               info2 = dmar_search_domain_by_dev_info(iommu->segment, bus, devfn);
+               info2 = dmar_search_domain_by_dev_info(info->segment, info->bus,
+                                                      info->devfn);
                if (info2) {
                        found      = info2->domain;
                        info2->dev = dev;

diff --git a/include/linux/intel-iommu.h b/include/linux/intel-iommu.h
index 21633ce..4100bd2 100644 (file)
--- a/include/linux/intel-iommu.h
+++ b/include/linux/intel-iommu.h
@@ -609,6 +609,7 @@ struct device_domain_info {
        struct list_head auxiliary_domains; /* auxiliary domains
                                             * attached to this device
                                             */
+       u32 segment;            /* PCI segment number */
        u8 bus;                 /* PCI bus number */
        u8 devfn;               /* PCI devfn number */
        u16 pfsid;              /* SRIOV physical function source ID */