drm/i915: Fix i915_dma_map_single positive error code

i915_dma_map_single relies on dma_mapping_error, which returns positive
error codes. Found by static checker.

Introduced by commit 678d96fbb3b5995a2fdff2bca5e1ab4a40b7e968
("drm/i915: Track GEN6 page table usage").

v2: Return negative error code and renamed commit title. (Dan)
v3: Missing reported-by tag (Daniel)

Reported-by: Dan Carpenter <[email protected]>
Cc: Dan Carpenter <[email protected]>
Cc: Mika Kuoppala <[email protected]>
Cc: Daniel Vetter <[email protected]>
Signed-off-by: Michel Thierry <[email protected]>
Reviewed-by: Mika Kuoppala <[email protected]>
Signed-off-by: Daniel Vetter <[email protected]>

diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.c b/drivers/gpu/drm/i915/i915_gem_gtt.c
index 9903bb0097a6f12183cd5d5f9a73087c70d52db0..9c155d1f852f4c6127964ced8669f1582870d0ef 100644 (file)
--- a/drivers/gpu/drm/i915/i915_gem_gtt.c
+++ b/drivers/gpu/drm/i915/i915_gem_gtt.c
@@ -311,7 +311,10 @@ static inline int i915_dma_map_page_single(struct page *page,
        struct device *device = &dev->pdev->dev;
 
        *daddr = dma_map_page(device, page, 0, 4096, PCI_DMA_BIDIRECTIONAL);
-       return dma_mapping_error(device, *daddr);
+       if (dma_mapping_error(device, *daddr))
+               return -ENOMEM;
+
+       return 0;
 }
 
 static void unmap_and_free_pt(struct i915_page_table_entry *pt,