> From: Cornelia Huck [mailto:cornelia.huck@xxxxxxxxxx] > On Fri, 18 May 2007 09:30:09 -0700, > "Williams, Dan J" <dan.j.williams@xxxxxxxxx> wrote: > > > When CONFIG_DMA_ENGINE=n async_tx_find_channel takes the form: > > ... async_tx_find_channel( ... ) > > { > > return NULL; > > } > > > > So in the S390 case the entire asynchronous path will be compiled away. > > Unfortunately, do_async_xor() (and others) is not ifdef'ed and contains > dma_map_page(), which led to the compile failure... The approach I have taken is to add the missing definitions to include/asm-s390/dma-mapping.h [ a non-outlook-mangled version of the patch is pushed out in my rebased git tree ]. I was not able to fully compile-test this change as the three s390-cross-toolchains I tried each died early in the kernel build process. The most common error was: "s390-unknown-linux-gnu-ld: unrecognised emulation mode: elf64_s390" --- s390: add dma mapping api stub definitions for async_tx From: Dan Williams <dan.j.williams@xxxxxxxxx> The asynchronous path in async_tx is meant to be compiled away on platforms like s390 with CONFIG_DMA_ENGINE=n. However, it is difficult to compile something away if it does not compile in the first place. This patch adds the missing dma api definitions as BUG() stubs. Cc: Cornelia Huck <cornelia.huck@xxxxxxxxxx> Signed-off-by: Dan Williams <dan.j.williams@xxxxxxxxx> --- include/asm-s390/dma-mapping.h | 78 ++++++++++++++++++++++++++++++++++++++++ 1 files changed, 78 insertions(+), 0 deletions(-) diff --git a/include/asm-s390/dma-mapping.h b/include/asm-s390/dma-mapping.h index 3f8c12f..33a3c82 100644 --- a/include/asm-s390/dma-mapping.h +++ b/include/asm-s390/dma-mapping.h @@ -4,9 +4,87 @@ * S390 version * * This file exists so that #include <dma-mapping.h> doesn't break anything. + * It also includes stub definitions of the API so common code like async_tx + * can compile. */ #ifndef _ASM_DMA_MAPPING_H #define _ASM_DMA_MAPPING_H +#include <linux/mm.h> +#include <asm/scatterlist.h> + +static inline dma_addr_t +dma_map_single(struct device *dev, void *cpu_addr, size_t size, + enum dma_data_direction dir) +{ + BUG(); + return 0; +} + +static inline dma_addr_t +dma_map_page(struct device *dev, struct page *page, + unsigned long offset, size_t size, + enum dma_data_direction dir) +{ + BUG(); + return 0; +} + +static inline void +dma_unmap_single(struct device *dev, dma_addr_t handle, size_t size, + enum dma_data_direction dir) +{ + BUG(); +} + +static inline void +dma_unmap_page(struct device *dev, dma_addr_t handle, size_t size, + enum dma_data_direction dir) +{ + BUG(); +} + +static inline int +dma_map_sg(struct device *dev, struct scatterlist *sg, int nents, + enum dma_data_direction dir) +{ + BUG(); + return 0; +} + +static inline void +dma_unmap_sg(struct device *dev, struct scatterlist *sg, int nents, + enum dma_data_direction dir) +{ + BUG(); +} + +static inline void +dma_sync_single_for_cpu(struct device *dev, dma_addr_t handle, size_t size, + enum dma_data_direction dir) +{ + BUG(); +} + +static inline void +dma_sync_single_for_device(struct device *dev, dma_addr_t handle, size_t size, + enum dma_data_direction dir) +{ + BUG(); +} + +static inline void +dma_sync_sg_for_cpu(struct device *dev, struct scatterlist *sg, int nents, + enum dma_data_direction dir) +{ + BUG(); +} + +static inline void +dma_sync_sg_for_device(struct device *dev, struct scatterlist *sg, int nents, + enum dma_data_direction dir) +{ + BUG(); +} #endif /* _ASM_DMA_MAPPING_H */ - To unsubscribe from this list: send the line "unsubscribe linux-s390" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
