Merge tag 'iommu-updates-v4.12' of git://git.kernel.org/pub/scm/linux/kernel/git...

[platform/kernel/linux-rpi.git] / arch / arm / mm / dma-mapping.c

diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c
index 475811f..c742dfd 100644 (file)
--- a/arch/arm/mm/dma-mapping.c
+++ b/arch/arm/mm/dma-mapping.c
@@ -2408,12 +2408,28 @@ void arch_setup_dma_ops(struct device *dev, u64 dma_base, u64 size,
        const struct dma_map_ops *dma_ops;
 
        dev->archdata.dma_coherent = coherent;
+
+       /*
+        * Don't override the dma_ops if they have already been set. Ideally
+        * this should be the only location where dma_ops are set, remove this
+        * check when all other callers of set_dma_ops will have disappeared.
+        */
+       if (dev->dma_ops)
+               return;
+
        if (arm_setup_iommu_dma_ops(dev, dma_base, size, iommu))
                dma_ops = arm_get_iommu_dma_map_ops(coherent);
        else
                dma_ops = arm_get_dma_map_ops(coherent);
 
        set_dma_ops(dev, dma_ops);
+
+#ifdef CONFIG_XEN
+       if (xen_initial_domain()) {
+               dev->archdata.dev_dma_ops = dev->dma_ops;
+               dev->dma_ops = xen_dma_ops;
+       }
+#endif
 }
 
 void arch_teardown_dma_ops(struct device *dev)