iommu/vt-d: Introduce helper function iova_size() to improve code readability

Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>

1 files changed, 5 insertions, 0 deletions

diff --git a/include/linux/iova.h b/include/linux/iova.h
index 3277f4711349..19e81d5ccb6d 100644
--- a/include/linux/iova.h
+++ b/include/linux/iova.h
@@ -34,6 +34,11 @@ struct iova_domain {
         unsigned long   dma_32bit_pfn;
 };
 
+static inline unsigned long iova_size(struct iova *iova)
+{
+        return iova->pfn_hi - iova->pfn_lo + 1;
+}
+
 struct iova *alloc_iova_mem(void);
 void free_iova_mem(struct iova *iova);
 void free_iova(struct iova_domain *iovad, unsigned long pfn);