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

[Lucas Stach]

From: Russell King <rmk+ker...@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