iommu/amd: Rearrange attach device code

attach_device() is just holding lock and calling do_attach(). There is
not need to have another function. Just move do_attach() code to
attach_device(). Similarly move do_detach() code to detach_device().

Signed-off-by: Vasant Hegde <vasant.hegde@amd.com>
Reviewed-by: Joerg Roedel <jroedel@suse.de>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/20241030063556.6104-9-vasant.hegde@amd.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>

Author: hegdevasant

drivers/iommu/amd/iommu.c

@@ -2081,80 +2081,42 @@ static void pdom_detach_iommu(struct amd_iommu *iommu,
 	spin_unlock_irqrestore(&pdom->lock, flags);
 }
 
-static int do_attach(struct iommu_dev_data *dev_data,
-		     struct protection_domain *domain)
+/*
+ * If a device is not yet associated with a domain, this function makes the
+ * device visible in the domain
+ */
+static int attach_device(struct device *dev,
+			 struct protection_domain *domain)
 {
+	struct iommu_dev_data *dev_data = dev_iommu_priv_get(dev);
 	struct amd_iommu *iommu = get_amd_iommu_from_dev_data(dev_data);
 	int ret = 0;
 
+	spin_lock(&dev_data->lock);
+
+	if (dev_data->domain != NULL) {
+		ret = -EBUSY;
+		goto out;
+	}
+
 	/* Update data structures */
 	dev_data->domain = domain;
 	list_add(&dev_data->list, &domain->dev_list);
 
 	/* Do reference counting */
 	ret = pdom_attach_iommu(iommu, domain);
 	if (ret)
-		return ret;
+		goto out;
 
 	/* Setup GCR3 table */
 	if (pdom_is_sva_capable(domain)) {
 		ret = init_gcr3_table(dev_data, domain);
 		if (ret) {
 			pdom_detach_iommu(iommu, domain);
-			return ret;
+			goto out;
 		}
 	}
 
-	return ret;
-}
-
-static void do_detach(struct iommu_dev_data *dev_data)
-{
-	struct protection_domain *domain = dev_data->domain;
-	struct amd_iommu *iommu = get_amd_iommu_from_dev_data(dev_data);
-	unsigned long flags;
-
-	/* Clear DTE and flush the entry */
-	dev_update_dte(dev_data, false);
-
-	/* Flush IOTLB and wait for the flushes to finish */
-	spin_lock_irqsave(&domain->lock, flags);
-	amd_iommu_domain_flush_all(domain);
-	spin_unlock_irqrestore(&domain->lock, flags);
-
-	/* Clear GCR3 table */
-	if (pdom_is_sva_capable(domain))
-		destroy_gcr3_table(dev_data, domain);
-
-	/* Update data structures */
-	dev_data->domain = NULL;
-	list_del(&dev_data->list);
-
-	/* decrease reference counters - needs to happen after the flushes */
-	pdom_detach_iommu(iommu, domain);
-}
-
-/*
- * If a device is not yet associated with a domain, this function makes the
- * device visible in the domain
- */
-static int attach_device(struct device *dev,
-			 struct protection_domain *domain)
-{
-	struct iommu_dev_data *dev_data;
-	int ret = 0;
-
-	dev_data = dev_iommu_priv_get(dev);
-
-	spin_lock(&dev_data->lock);
-
-	if (dev_data->domain != NULL) {
-		ret = -EBUSY;
-		goto out;
-	}
-
-	ret = do_attach(dev_data, domain);
-
 out:
 	spin_unlock(&dev_data->lock);
 
@@ -2168,7 +2130,9 @@ static void detach_device(struct device *dev)
 {
 	struct iommu_dev_data *dev_data = dev_iommu_priv_get(dev);
 	struct amd_iommu *iommu = get_amd_iommu_from_dev_data(dev_data);
+	struct protection_domain *domain = dev_data->domain;
 	bool ppr = dev_data->ppr;
+	unsigned long flags;
 
 	spin_lock(&dev_data->lock);
 
@@ -2188,7 +2152,24 @@ static void detach_device(struct device *dev)
 		dev_data->ppr = false;
 	}
 
-	do_detach(dev_data);
+	/* Clear DTE and flush the entry */
+	dev_update_dte(dev_data, false);
+
+	/* Flush IOTLB and wait for the flushes to finish */
+	spin_lock_irqsave(&domain->lock, flags);
+	amd_iommu_domain_flush_all(domain);
+	spin_unlock_irqrestore(&domain->lock, flags);
+
+	/* Clear GCR3 table */
+	if (pdom_is_sva_capable(domain))
+		destroy_gcr3_table(dev_data, domain);
+
+	/* Update data structures */
+	dev_data->domain = NULL;
+	list_del(&dev_data->list);
+
+	/* decrease reference counters - needs to happen after the flushes */
+	pdom_detach_iommu(iommu, domain);
 
 out:
 	spin_unlock(&dev_data->lock);