[PATCH rc v7 3/6] iommu: Fix pasid attach in pci_dev_reset_iommu_prepare/done()

[Nicolin Chen]

Now the helpers handle per-gdev resets. So use the per-device API properly
to attach/detach PASIDs. Also add max_pasids check as other callers.

Fixes: c279e83953d9 ("iommu: Introduce pci_dev_reset_iommu_prepare/done()")
Cc: stable@xxxxxxxxxxxxxxx
Reported-by: Shuai Xue <xueshuai@xxxxxxxxxxxxxxxxx>
Closes: https://lore.kernel.org/all/ad858513-09fc-455e-bbc5-fe38a225cc78@xxxxxxxxxxxxxxxxx/
Reviewed-by: Shuai Xue <xueshuai@xxxxxxxxxxxxxxxxx>
Reviewed-by: Jason Gunthorpe <jgg@xxxxxxxxxx>
Reviewed-by: Kevin Tian <kevin.tian@xxxxxxxxx>
Signed-off-by: Nicolin Chen <nicolinc@xxxxxxxxxx>
---
 drivers/iommu/iommu.c | 25 ++++++++++++++++++-------
 1 file changed, 18 insertions(+), 7 deletions(-)

diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
index d5d9102b9d750..e9ffa562b614f 100644
--- a/drivers/iommu/iommu.c
+++ b/drivers/iommu/iommu.c
@@ -4026,9 +4026,14 @@ int pci_dev_reset_iommu_prepare(struct pci_dev *pdev)
 	 * The pasid_array is mostly fenced by group->mutex, except one reader
 	 * in iommu_attach_handle_get(), so it's safe to read without xa_lock.
 	 */
-	xa_for_each_start(&group->pasid_array, pasid, entry, 1)
-		iommu_remove_dev_pasid(&pdev->dev, pasid,
-				       pasid_array_entry_to_domain(entry));
+	if (pdev->dev.iommu->max_pasids > 0) {
+		xa_for_each_start(&group->pasid_array, pasid, entry, 1) {
+			struct iommu_domain *pasid_dom =
+				pasid_array_entry_to_domain(entry);
+
+			iommu_remove_dev_pasid(&pdev->dev, pasid, pasid_dom);
+		}
+	}
 
 	group->recovery_cnt++;
 	return ret;
@@ -4090,10 +4095,16 @@ void pci_dev_reset_iommu_done(struct pci_dev *pdev)
 	 * The pasid_array is mostly fenced by group->mutex, except one reader
 	 * in iommu_attach_handle_get(), so it's safe to read without xa_lock.
 	 */
-	xa_for_each_start(&group->pasid_array, pasid, entry, 1)
-		WARN_ON(__iommu_set_group_pasid(
-			pasid_array_entry_to_domain(entry), group, pasid,
-			group->blocking_domain));
+	if (pdev->dev.iommu->max_pasids > 0) {
+		xa_for_each_start(&group->pasid_array, pasid, entry, 1) {
+			struct iommu_domain *pasid_dom =
+				pasid_array_entry_to_domain(entry);
+
+			WARN_ON(pasid_dom->ops->set_dev_pasid(
+				pasid_dom, &pdev->dev, pasid,
+				group->blocking_domain));
+		}
+	}
 
 	if (!WARN_ON(group->recovery_cnt == 0))
 		group->recovery_cnt--;
-- 
2.43.0