iommu/amd: Introduce helper function amd_iommu_update_dte()

Which includes DTE update, clone_aliases, DTE flush and completion-wait
commands to avoid code duplication when reuse to setup DTE for nested
translation.

Also, make amd_iommu_update_dte() non-static to reuse in
in a new nested.c file for nested translation.

Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>

Author: ssuthiku-amd

drivers/iommu/amd/amd_iommu.h

@@ -190,6 +190,10 @@ void amd_iommu_domain_set_pgtable(struct protection_domain *domain,
 struct dev_table_entry *get_dev_table(struct amd_iommu *iommu);
 struct iommu_dev_data *search_dev_data(struct amd_iommu *iommu, u16 devid);
 
+void amd_iommu_update_dte(struct amd_iommu *iommu,
+			  struct iommu_dev_data *dev_data,
+			  struct dev_table_entry *new);
+
 static inline void
 amd_iommu_make_clear_dte(struct iommu_dev_data *dev_data, struct dev_table_entry *new)
 {

drivers/iommu/amd/iommu.c

@@ -76,6 +76,8 @@ static void set_dte_entry(struct amd_iommu *iommu,
 			  struct iommu_dev_data *dev_data,
 			  phys_addr_t top_paddr, unsigned int top_level);
 
+static int device_flush_dte(struct iommu_dev_data *dev_data);
+
 static void amd_iommu_change_top(struct pt_iommu *iommu_table,
 				 phys_addr_t top_paddr, unsigned int top_level);
 
@@ -86,6 +88,10 @@ static bool amd_iommu_enforce_cache_coherency(struct iommu_domain *domain);
 static int amd_iommu_set_dirty_tracking(struct iommu_domain *domain,
 					bool enable);
 
+static void clone_aliases(struct amd_iommu *iommu, struct device *dev);
+
+static int iommu_completion_wait(struct amd_iommu *iommu);
+
 /****************************************************************************
  *
  * Helper functions
@@ -203,6 +209,16 @@ static void update_dte256(struct amd_iommu *iommu, struct iommu_dev_data *dev_da
 	spin_unlock_irqrestore(&dev_data->dte_lock, flags);
 }
 
+void amd_iommu_update_dte(struct amd_iommu *iommu,
+			     struct iommu_dev_data *dev_data,
+			     struct dev_table_entry *new)
+{
+	update_dte256(iommu, dev_data, new);
+	clone_aliases(iommu, dev_data->dev);
+	device_flush_dte(dev_data);
+	iommu_completion_wait(iommu);
+}
+
 static void get_dte256(struct amd_iommu *iommu, struct iommu_dev_data *dev_data,
 		      struct dev_table_entry *dte)
 {
@@ -2127,7 +2143,7 @@ static void set_dte_entry(struct amd_iommu *iommu,
 
 	set_dte_gcr3_table(iommu, dev_data, &new);
 
-	update_dte256(iommu, dev_data, &new);
+	amd_iommu_update_dte(iommu, dev_data, &new);
 
 	/*
 	 * A kdump kernel might be replacing a domain ID that was copied from
@@ -2147,7 +2163,7 @@ static void clear_dte_entry(struct amd_iommu *iommu, struct iommu_dev_data *dev_
 	struct dev_table_entry new = {};
 
 	amd_iommu_make_clear_dte(dev_data, &new);
-	update_dte256(iommu, dev_data, &new);
+	amd_iommu_update_dte(iommu, dev_data, &new);
 }
 
 /* Update and flush DTE for the given device */
@@ -2159,10 +2175,6 @@ static void dev_update_dte(struct iommu_dev_data *dev_data, bool set)
 		set_dte_entry(iommu, dev_data, 0, 0);
 	else
 		clear_dte_entry(iommu, dev_data);
-
-	clone_aliases(iommu, dev_data->dev);
-	device_flush_dte(dev_data);
-	iommu_completion_wait(iommu);
 }
 
 /*