intel-iommu: Add iommu_should_identity_map() function
We do this twice, and it's about to get more complicated. This makes the
code slightly clearer about what it's doing, too.
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
diff --git a/drivers/pci/intel-iommu.c b/drivers/pci/intel-iommu.c
index 73a5c71..ae5ccdf 100644
--- a/drivers/pci/intel-iommu.c
+++ b/drivers/pci/intel-iommu.c
@@ -2442,6 +2442,11 @@
return pdev->dev.archdata.iommu == DUMMY_DEVICE_DOMAIN_INFO;
}
+static int iommu_should_identity_map(struct pci_dev *pdev)
+{
+ return pdev->dma_mask > DMA_BIT_MASK(32);
+}
+
/* Check if the pdev needs to go through non-identity map and unmap process.*/
static int iommu_no_mapping(struct pci_dev *pdev)
{
@@ -2455,7 +2460,7 @@
found = identity_mapping(pdev);
if (found) {
- if (pdev->dma_mask > DMA_BIT_MASK(32))
+ if (iommu_should_identity_map(pdev))
return 1;
else {
/*
@@ -2472,7 +2477,7 @@
* In case of a detached 64 bit DMA device from vm, the device
* is put into si_domain for identity mapping.
*/
- if (pdev->dma_mask > DMA_BIT_MASK(32)) {
+ if (iommu_should_identity_map(pdev)) {
int ret;
ret = domain_add_dev_info(si_domain, pdev);
if (ret)