iommu: Do iommu_group_create_direct_mappings() before attach

The iommu_probe_device() path calls iommu_create_device_direct_mappings()
after attaching the device.

IOMMU_RESV_DIRECT maps need to be continually in place, so if a hotplugged
device has new ranges the should have been mapped into the default domain
before it is attached.

Move the iommu_create_device_direct_mappings() call up.
Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Tested-by: Heiko Stuebner <heiko@sntech.de>
Tested-by: Niklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/10-v5-1b99ae392328+44574-iommu_err_unwind_jgg@nvidia.comSigned-off-by: Joerg Roedel <jroedel@suse.de>

drivers/iommu/iommu.c

@@ -423,6 +423,8 @@ int iommu_probe_device(struct device *dev)
 
 	mutex_lock(&group->mutex);
 
+	iommu_create_device_direct_mappings(group, dev);
+
 	if (group->domain) {
 		ret = __iommu_device_set_domain(group, dev, group->domain, 0);
 	} else if (!group->default_domain) {
@@ -434,9 +436,11 @@ int iommu_probe_device(struct device *dev)
 		 */
 		iommu_alloc_default_domain(group, dev);
 		group->domain = NULL;
-		if (group->default_domain)
+		if (group->default_domain) {
+			iommu_create_device_direct_mappings(group, dev);
 			ret = __iommu_group_set_domain(group,
 						       group->default_domain);
+		}
 
 		/*
 		 * We assume that the iommu driver starts up the device in
@@ -447,8 +451,6 @@ int iommu_probe_device(struct device *dev)
 	if (ret)
 		goto err_unlock;
 
-	iommu_create_device_direct_mappings(group, dev);
-
 	mutex_unlock(&group->mutex);
 	iommu_group_put(group);