iommu: Remove the remove_dev_pasid op

The iommu drivers that supports PASID have supported attaching pasid to the
blocked_domain, hence remove the remove_dev_pasid op from the iommu_ops.

Reviewed-by: Jason Gunthorpe <[email protected]>
Reviewed-by: Kevin Tian <[email protected]>
Reviewed-by: Vasant Hegde <[email protected]>
Reviewed-by: Lu Baolu <[email protected]>
Signed-off-by: Yi Liu <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Joerg Roedel <[email protected]>

Author: yiliu1765

drivers/iommu/iommu.c

@@ -3317,17 +3317,9 @@ static void iommu_remove_dev_pasid(struct device *dev, ioasid_t pasid,
 {
 	const struct iommu_ops *ops = dev_iommu_ops(dev);
 	struct iommu_domain *blocked_domain = ops->blocked_domain;
-	int ret = 1;
 
-	if (blocked_domain && blocked_domain->ops->set_dev_pasid) {
-		ret = blocked_domain->ops->set_dev_pasid(blocked_domain,
-							 dev, pasid, domain);
-	} else {
-		ops->remove_dev_pasid(dev, pasid, domain);
-		ret = 0;
-	}
-
-	WARN_ON(ret);
+	WARN_ON(blocked_domain->ops->set_dev_pasid(blocked_domain,
+						   dev, pasid, domain));
 }
 
 static int __iommu_set_group_pasid(struct iommu_domain *domain,
@@ -3390,9 +3382,8 @@ int iommu_attach_device_pasid(struct iommu_domain *domain,
 	ops = dev_iommu_ops(dev);
 
 	if (!domain->ops->set_dev_pasid ||
-	    (!ops->remove_dev_pasid &&
-	     (!ops->blocked_domain ||
-	      !ops->blocked_domain->ops->set_dev_pasid)))
+	    !ops->blocked_domain ||
+	    !ops->blocked_domain->ops->set_dev_pasid)
 		return -EOPNOTSUPP;
 
 	if (ops != domain->owner || pasid == IOMMU_NO_PASID)

include/linux/iommu.h

@@ -587,9 +587,6 @@ iommu_copy_struct_from_full_user_array(void *kdst, size_t kdst_entry_size,
  *		- IOMMU_DOMAIN_DMA: must use a dma domain
  *		- 0: use the default setting
  * @default_domain_ops: the default ops for domains
- * @remove_dev_pasid: Remove any translation configurations of a specific
- *                    pasid, so that any DMA transactions with this pasid
- *                    will be blocked by the hardware.
  * @viommu_alloc: Allocate an iommufd_viommu on a physical IOMMU instance behind
  *                the @dev, as the set of virtualization resources shared/passed
  *                to user space IOMMU instance. And associate it with a nesting
@@ -647,8 +644,6 @@ struct iommu_ops {
 			      struct iommu_page_response *msg);
 
 	int (*def_domain_type)(struct device *dev);
-	void (*remove_dev_pasid)(struct device *dev, ioasid_t pasid,
-				 struct iommu_domain *domain);
 
 	struct iommufd_viommu *(*viommu_alloc)(
 		struct device *dev, struct iommu_domain *parent_domain,