On Tue, 9 Apr 2019 05:22:41 -0700 Christoph Hellwig <hch@xxxxxxxxxxxxx> wrote: > > +++ b/arch/s390/include/asm/dma-mapping.h > > @@ -0,0 +1,13 @@ > > +/* SPDX-License-Identifier: GPL-2.0 */ > > +#ifndef _ASM_S390_DMA_MAPPING_H > > +#define _ASM_S390_DMA_MAPPING_H > > + > > +#include <linux/dma-contiguous.h> > > + > > +static inline const struct dma_map_ops *get_arch_dma_ops(struct bus_type *bus) > > +{ > > + return NULL; > > +} > > + > > +#endif /* _ASM_S390_DMA_MAPPING_H */ > > + > > Congratulations! You ust create an entirely pointless duplicate of > include/asm-generic/dma-mapping.h. > Right! Thanks for spotting. There was a stage in development when my arch/s390/include/asm/dma-mapping.h looked quite different, but I did end up with an entirely pointless duplicate indeed. I will fix it for v1. Regards, Halil