[PATCH v2 3/3] iommu/vt-d: Fix ineffective devTLB invalidation for subdevices

[Liu Yi L]

iommu_flush_dev_iotlb() is called to invalidate caches on device. It only
loops the devices which are full-attached to the domain. For sub-devices,
this is ineffective. This results in invalid caching entries left on the
device. Fix it by adding loop for subdevices as well. Also, the domain->
has_iotlb_device needs to be updated when attaching to subdevices.

Fixes: 67b8e02b5e761 ("iommu/vt-d: Aux-domain specific domain attach/detach")
Signed-off-by: Liu Yi L <yi.l....@intel.com>
---
 drivers/iommu/intel/iommu.c | 63 +++++++++++++++++++++++++++----------
 1 file changed, 47 insertions(+), 16 deletions(-)

diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c
index acfe0a5b955e..e97c5ac1d7fc 100644
--- a/drivers/iommu/intel/iommu.c
+++ b/drivers/iommu/intel/iommu.c
@@ -726,6 +726,8 @@ static int domain_update_device_node(struct dmar_domain 
*domain)
        return nid;
 }
 
+static void domain_update_iotlb(struct dmar_domain *domain);
+
 /* Some capabilities may be different across iommus */
 static void domain_update_iommu_cap(struct dmar_domain *domain)
 {
@@ -739,6 +741,8 @@ static void domain_update_iommu_cap(struct dmar_domain 
*domain)
         */
        if (domain->nid == NUMA_NO_NODE)
                domain->nid = domain_update_device_node(domain);
+
+       domain_update_iotlb(domain);
 }
 
 struct context_entry *iommu_context_addr(struct intel_iommu *iommu, u8 bus,
@@ -1459,6 +1463,18 @@ iommu_support_dev_iotlb (struct dmar_domain *domain, 
struct intel_iommu *iommu,
        return NULL;
 }
 
+static bool dev_iotlb_enabled(struct device_domain_info *info)
+{
+       struct pci_dev *pdev;
+
+       if (!info->dev || !dev_is_pci(info->dev))
+               return false;
+
+       pdev = to_pci_dev(info->dev);
+
+       return !!pdev->ats_enabled;
+}
+
 static void domain_update_iotlb(struct dmar_domain *domain)
 {
        struct device_domain_info *info;
@@ -1466,17 +1482,20 @@ static void domain_update_iotlb(struct dmar_domain 
*domain)
 
        assert_spin_locked(&device_domain_lock);
 
-       list_for_each_entry(info, &domain->devices, link) {
-               struct pci_dev *pdev;
-
-               if (!info->dev || !dev_is_pci(info->dev))
-                       continue;
-
-               pdev = to_pci_dev(info->dev);
-               if (pdev->ats_enabled) {
+       list_for_each_entry(info, &domain->devices, link)
+               if (dev_iotlb_enabled(info)) {
                        has_iotlb_device = true;
                        break;
                }
+
+       if (!has_iotlb_device) {
+               struct subdev_domain_info *sinfo;
+
+               list_for_each_entry(sinfo, &domain->subdevices, link_domain)
+                       if (dev_iotlb_enabled(get_domain_info(sinfo->pdev))) {
+                               has_iotlb_device = true;
+                               break;
+                       }
        }
 
        domain->has_iotlb_device = has_iotlb_device;
@@ -1557,25 +1576,37 @@ static void iommu_disable_dev_iotlb(struct 
device_domain_info *info)
 #endif
 }
 
+static void __iommu_flush_dev_iotlb(struct device_domain_info *info,
+                                   u64 addr, unsigned int mask)
+{
+       u16 sid, qdep;
+
+       if (!info || !info->ats_enabled)
+               return;
+
+       sid = info->bus << 8 | info->devfn;
+       qdep = info->ats_qdep;
+       qi_flush_dev_iotlb(info->iommu, sid, info->pfsid,
+                          qdep, addr, mask);
+}
+
 static void iommu_flush_dev_iotlb(struct dmar_domain *domain,
                                  u64 addr, unsigned mask)
 {
-       u16 sid, qdep;
        unsigned long flags;
        struct device_domain_info *info;
+       struct subdev_domain_info *sinfo;
 
        if (!domain->has_iotlb_device)
                return;
 
        spin_lock_irqsave(&device_domain_lock, flags);
-       list_for_each_entry(info, &domain->devices, link) {
-               if (!info->ats_enabled)
-                       continue;
+       list_for_each_entry(info, &domain->devices, link)
+               __iommu_flush_dev_iotlb(info, addr, mask);
 
-               sid = info->bus << 8 | info->devfn;
-               qdep = info->ats_qdep;
-               qi_flush_dev_iotlb(info->iommu, sid, info->pfsid,
-                               qdep, addr, mask);
+       list_for_each_entry(sinfo, &domain->subdevices, link_domain) {
+               __iommu_flush_dev_iotlb(get_domain_info(sinfo->pdev),
+                                       addr, mask);
        }
        spin_unlock_irqrestore(&device_domain_lock, flags);
 }
-- 
2.25.1