iommu/vt-d: Set intel_iommu_gfx_mapped correctly

BugLink: https://bugs.launchpad.net/bugs/1836666

[ Upstream commit cf1ec453 ]

The intel_iommu_gfx_mapped flag is exported by the Intel
IOMMU driver to indicate whether an IOMMU is used for the
graphic device. In a virtualized IOMMU environment (e.g.
QEMU), an include-all IOMMU is used for graphic device.
This flag is found to be clear even the IOMMU is used.

Cc: Ashok Raj <ashok.raj@intel.com>
Cc: Jacob Pan <jacob.jun.pan@linux.intel.com>
Cc: Kevin Tian <kevin.tian@intel.com>
Reported-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Fixes: c0771df8 ("intel-iommu: Export a flag indicating that the IOMMU is used for iGFX.")
Suggested-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>
Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>

drivers/iommu/intel-iommu.c

@@ -3983,9 +3983,7 @@ static void __init init_no_remapping_devices(void)
 
 		/* This IOMMU has *only* gfx devices. Either bypass it or
 		   set the gfx_mapped flag, as appropriate */
-		if (dmar_map_gfx) {
-			intel_iommu_gfx_mapped = 1;
-		} else {
+		if (!dmar_map_gfx) {
 			drhd->ignored = 1;
 			for_each_active_dev_scope(drhd->devices,
 						  drhd->devices_cnt, i, dev)
@@ -4710,6 +4708,9 @@ int __init intel_iommu_init(void)
 		goto out_free_reserved_range;
 	}
 
+	if (dmar_map_gfx)
+		intel_iommu_gfx_mapped = 1;
+
 	init_no_remapping_devices();
 
 	ret = init_dmars();