[PATCH 2/6] iova: Add a per-domain count of reserved nodes

[John Garry]

To help learn if the domain has regular IOVA nodes, add a count of
reserved nodes, calculated at init time.

Signed-off-by: John Garry <john.garry@xxxxxxxxxx>
---
 drivers/iommu/iova.c | 2 ++
 include/linux/iova.h | 1 +
 2 files changed, 3 insertions(+)

diff --git a/drivers/iommu/iova.c b/drivers/iommu/iova.c
index e62e9e30b30c..cecc74fb8663 100644
--- a/drivers/iommu/iova.c
+++ b/drivers/iommu/iova.c
@@ -717,6 +717,8 @@ reserve_iova(struct iova_domain *iovad,
 	 * or need to insert remaining non overlap addr range
 	 */
 	iova = __insert_new_range(iovad, pfn_lo, pfn_hi);
+	if (iova)
+		iovad->reserved_node_count++;
 finish:
 
 	spin_unlock_irqrestore(&iovad->iova_rbtree_lock, flags);
diff --git a/include/linux/iova.h b/include/linux/iova.h
index c834c01c0a5b..fd3217a605b2 100644
--- a/include/linux/iova.h
+++ b/include/linux/iova.h
@@ -95,6 +95,7 @@ struct iova_domain {
 						   flush-queues */
 	atomic_t fq_timer_on;			/* 1 when timer is active, 0
 						   when not */
+	int reserved_node_count;
 };
 
 static inline unsigned long iova_size(struct iova *iova)
-- 
2.26.2