[PATCH RFC 052/111] staging: etnaviv: fix etnaviv_iommu_map_gem() return paths

[Lucas Stach]

From: Russell King <rmk+kernel at arm.linux.org.uk>

If etnaviv_iommu_map() fails, we returned an error, but we didn't clean
up the allocated drm_mm node.  Simplify the return path and add the
necessary failure clean up.

Signed-off-by: Russell King <rmk+kernel at arm.linux.org.uk>
---
 drivers/staging/etnaviv/etnaviv_mmu.c | 28 +++++++++++++++++-----------
 1 file changed, 17 insertions(+), 11 deletions(-)

diff --git a/drivers/staging/etnaviv/etnaviv_mmu.c b/drivers/staging/etnaviv/etnaviv_mmu.c
index 4fbba26a3f37..89c5713f52bc 100644
--- a/drivers/staging/etnaviv/etnaviv_mmu.c
+++ b/drivers/staging/etnaviv/etnaviv_mmu.c
@@ -95,8 +95,7 @@ int etnaviv_iommu_map_gem(struct etnaviv_iommu *mmu,
 	struct etnaviv_gem_object *etnaviv_obj)
 {
 	struct sg_table *sgt = etnaviv_obj->sgt;
-	uint32_t offset;
-	struct drm_mm_node *node = NULL;
+	struct drm_mm_node *node;
 	int ret;
 
 	/* v1 MMU can optimize single entry (contiguous) scatterlists */
@@ -138,18 +137,25 @@ int etnaviv_iommu_map_gem(struct etnaviv_iommu *mmu,
 		break;
 	}
 
-	if (!ret) {
-		mmu->last_iova = node->start + etnaviv_obj->base.size;
-		offset = node->start;
-		etnaviv_obj->iova = offset;
-		etnaviv_obj->gpu_vram_node = node;
+	if (ret < 0) {
+		kfree(node);
+		return ret;
+	}
+
+	mmu->last_iova = node->start + etnaviv_obj->base.size;
+	etnaviv_obj->iova = node->start;
+	etnaviv_obj->gpu_vram_node = node;
+	ret = etnaviv_iommu_map(mmu, node->start, sgt, etnaviv_obj->base.size,
+				IOMMU_READ | IOMMU_WRITE);
 
-		ret = etnaviv_iommu_map(mmu, offset, sgt,
-					etnaviv_obj->base.size,
-					IOMMU_READ | IOMMU_WRITE);
-	} else
+	if (ret < 0) {
+		drm_mm_remove_node(node);
 		kfree(node);
 
+		etnaviv_obj->iova = 0;
+		etnaviv_obj->gpu_vram_node = NULL;
+	}
+
 	return ret;
 }
 
-- 
2.1.4