iommu/vt-d: Make prq draining code generic

Currently draining page requests and responses for a pasid is part of SVA
implementation. This is because the driver only supports attaching an SVA
domain to a device pasid. As we are about to support attaching other types
of domains to a device pasid, the prq draining code becomes generic.

Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Link: https://lore.kernel.org/r/20230802212427.1497170-6-jacob.jun.pan@linux.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 ecb7e44..574021c 100644 (file)
--- a/drivers/iommu/intel/iommu.c
+++ b/drivers/iommu/intel/iommu.c
@@ -4727,21 +4727,29 @@ static void intel_iommu_remove_dev_pasid(struct device *dev, ioasid_t pasid)
        struct intel_iommu *iommu = device_to_iommu(dev, NULL, NULL);
        struct iommu_domain *domain;
 
-       /* Domain type specific cleanup: */
        domain = iommu_get_domain_for_dev_pasid(dev, pasid, 0);
-       if (domain) {
-               switch (domain->type) {
-               case IOMMU_DOMAIN_SVA:
-                       intel_svm_remove_dev_pasid(dev, pasid);
-                       break;
-               default:
-                       /* should never reach here */
-                       WARN_ON(1);
-                       break;
-               }
+       if (WARN_ON_ONCE(!domain))
+               goto out_tear_down;
+
+       /*
+        * The SVA implementation needs to handle its own stuffs like the mm
+        * notification. Before consolidating that code into iommu core, let
+        * the intel sva code handle it.
+        */
+       if (domain->type == IOMMU_DOMAIN_SVA) {
+               intel_svm_remove_dev_pasid(dev, pasid);
+               goto out_tear_down;
        }
 
+       /*
+        * Should never reach here until we add support for attaching
+        * non-SVA domain to a pasid.
+        */
+       WARN_ON(1);
+
+out_tear_down:
        intel_pasid_tear_down_entry(iommu, dev, pasid, false);
+       intel_drain_pasid_prq(dev, pasid);
 }
 
 const struct iommu_ops intel_iommu_ops = {

diff --git a/drivers/iommu/intel/iommu.h b/drivers/iommu/intel/iommu.h
index 1c5e1d8..6d94a29 100644 (file)
--- a/drivers/iommu/intel/iommu.h
+++ b/drivers/iommu/intel/iommu.h
@@ -844,6 +844,7 @@ int intel_svm_page_response(struct device *dev, struct iommu_fault_event *evt,
                            struct iommu_page_response *msg);
 struct iommu_domain *intel_svm_domain_alloc(void);
 void intel_svm_remove_dev_pasid(struct device *dev, ioasid_t pasid);
+void intel_drain_pasid_prq(struct device *dev, u32 pasid);
 
 struct intel_svm_dev {
        struct list_head list;
@@ -862,6 +863,7 @@ struct intel_svm {
 };
 #else
 static inline void intel_svm_check(struct intel_iommu *iommu) {}
+static inline void intel_drain_pasid_prq(struct device *dev, u32 pasid) {}
 static inline struct iommu_domain *intel_svm_domain_alloc(void)
 {
        return NULL;

diff --git a/drivers/iommu/intel/svm.c b/drivers/iommu/intel/svm.c
index 2a82864..9fbae9a 100644 (file)
--- a/drivers/iommu/intel/svm.c
+++ b/drivers/iommu/intel/svm.c
@@ -26,8 +26,6 @@
 #include "trace.h"
 
 static irqreturn_t prq_event_thread(int irq, void *d);
-static void intel_svm_drain_prq(struct device *dev, u32 pasid);
-#define to_intel_svm_dev(handle) container_of(handle, struct intel_svm_dev, sva)
 
 static DEFINE_XARRAY_ALLOC(pasid_private_array);
 static int pasid_private_add(ioasid_t pasid, void *priv)
@@ -382,17 +380,6 @@ void intel_svm_remove_dev_pasid(struct device *dev, u32 pasid)
 
        if (sdev) {
                list_del_rcu(&sdev->list);
-               /*
-                * Flush the PASID cache and IOTLB for this device.
-                * Note that we do depend on the hardware *not* using
-                * the PASID any more. Just as we depend on other
-                * devices never using PASIDs that they have no right
-                * to use. We have a *shared* PASID table, because it's
-                * large and has to be physically contiguous. So it's
-                * hard to be as defensive as we might like.
-                */
-               intel_pasid_tear_down_entry(iommu, dev, svm->pasid, false);
-               intel_svm_drain_prq(dev, svm->pasid);
                kfree_rcu(sdev, rcu);
 
                if (list_empty(&svm->devs)) {
@@ -449,7 +436,7 @@ static bool is_canonical_address(u64 addr)
 }
 
 /**
- * intel_svm_drain_prq - Drain page requests and responses for a pasid
+ * intel_drain_pasid_prq - Drain page requests and responses for a pasid
  * @dev: target device
  * @pasid: pasid for draining
  *
@@ -463,7 +450,7 @@ static bool is_canonical_address(u64 addr)
  * described in VT-d spec CH7.10 to drain all page requests and page
  * responses pending in the hardware.
  */
-static void intel_svm_drain_prq(struct device *dev, u32 pasid)
+void intel_drain_pasid_prq(struct device *dev, u32 pasid)
 {
        struct device_domain_info *info;
        struct dmar_domain *domain;