[PATCH 2/2] vfio/type1: Add iommu_unmap error check when vfio_unmap_unpin

[Suravee Suthikulpanit <suravee.suthikulpanit@xxxxxxx>]

Besides zero check the number of unmapped page, also check
and handle iommu_unmap errors.

Cc: Alex Williamson <alex.williamson@xxxxxxxxxx>
Cc: Joerg Roedel <joro@xxxxxxxxxx>
Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@xxxxxxx>
---
 drivers/vfio/vfio_iommu_type1.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
index e30e29a..c580518 100644
--- a/drivers/vfio/vfio_iommu_type1.c
+++ b/drivers/vfio/vfio_iommu_type1.c
@@ -677,7 +677,8 @@ static long vfio_unmap_unpin(struct vfio_iommu *iommu, struct vfio_dma *dma,
 	}
 
 	while (iova < end) {
-		size_t unmapped, len;
+		ssize_t unmapped;
+		size_t len;
 		phys_addr_t phys, next;
 
 		phys = iommu_iova_to_phys(domain->domain, iova);
@@ -699,7 +700,7 @@ static long vfio_unmap_unpin(struct vfio_iommu *iommu, struct vfio_dma *dma,
 		}
 
 		unmapped = iommu_unmap(domain->domain, iova, len);
-		if (WARN_ON(!unmapped))
+		if (WARN_ON(unmapped <= 0))
 			break;
 
 		unlocked += vfio_unpin_pages_remote(dma, iova,
-- 
1.8.3.1