From: Dan Williams Continuing the work started in 411f0f3edc141a582190d3605cadd1d993abb6df ... This enables code with a dma path, that compiles away, to build without requiring additional code factoring. It also prevents code that calls dma_alloc_coherent and dma_free_coherent from linking whereas previously the code would hit a BUG() at run time. Finally, it allows archs that set !HAS_DMA to delete their asm/dma-mapping.h file. Cc: Cornelia Huck Cc: Martin Schwidefsky Cc: Heiko Carstens Cc: John W. Linville Cc: Kyle McMartin Cc: James Bottomley Cc: Tejun Heo Cc: Jeff Garzik Cc: Cc: Cc: Cc: Signed-off-by: Dan Williams Signed-off-by: Andrew Morton --- arch/arm26/Kconfig | 3 arch/h8300/Kconfig | 3 arch/m32r/Kconfig | 3 drivers/dma/Kconfig | 2 include/asm-arm26/dma-mapping.h | 2 include/asm-generic/dma-mapping-broken.h | 82 +++++++++++++++++---- include/asm-h8300/dma-mapping.h | 1 include/asm-m32r/dma-mapping.h | 6 - include/asm-s390/dma-mapping.h | 12 --- include/linux/dma-mapping.h | 4 + 10 files changed, 84 insertions(+), 34 deletions(-) diff -puN arch/arm26/Kconfig~dma-mapping-prevent-dma-dependent-code-from-linking-on arch/arm26/Kconfig --- a/arch/arm26/Kconfig~dma-mapping-prevent-dma-dependent-code-from-linking-on +++ a/arch/arm26/Kconfig @@ -17,6 +17,9 @@ config MMU bool default y +config NO_DMA + def_bool y + config ARCH_ACORN bool default y diff -puN arch/h8300/Kconfig~dma-mapping-prevent-dma-dependent-code-from-linking-on arch/h8300/Kconfig --- a/arch/h8300/Kconfig~dma-mapping-prevent-dma-dependent-code-from-linking-on +++ a/arch/h8300/Kconfig @@ -68,6 +68,9 @@ config TIME_LOW_RES config NO_IOPORT def_bool y +config NO_DMA + def_bool y + config ISA bool default y diff -puN arch/m32r/Kconfig~dma-mapping-prevent-dma-dependent-code-from-linking-on arch/m32r/Kconfig --- a/arch/m32r/Kconfig~dma-mapping-prevent-dma-dependent-code-from-linking-on +++ a/arch/m32r/Kconfig @@ -31,6 +31,9 @@ config GENERIC_IRQ_PROBE config NO_IOPORT def_bool y +config NO_DMA + def_bool y + source "init/Kconfig" diff -puN drivers/dma/Kconfig~dma-mapping-prevent-dma-dependent-code-from-linking-on drivers/dma/Kconfig --- a/drivers/dma/Kconfig~dma-mapping-prevent-dma-dependent-code-from-linking-on +++ a/drivers/dma/Kconfig @@ -3,7 +3,7 @@ # menu "DMA Engine support" - depends on !S390 + depends on HAS_DMA config DMA_ENGINE bool "Support for DMA engines" diff -puN include/asm-arm26/dma-mapping.h~dma-mapping-prevent-dma-dependent-code-from-linking-on /dev/null --- a/include/asm-arm26/dma-mapping.h +++ /dev/null @@ -1,2 +0,0 @@ -#include - diff -puN include/asm-generic/dma-mapping-broken.h~dma-mapping-prevent-dma-dependent-code-from-linking-on include/asm-generic/dma-mapping-broken.h --- a/include/asm-generic/dma-mapping-broken.h~dma-mapping-prevent-dma-dependent-code-from-linking-on +++ a/include/asm-generic/dma-mapping-broken.h @@ -1,24 +1,82 @@ #ifndef _ASM_GENERIC_DMA_MAPPING_H #define _ASM_GENERIC_DMA_MAPPING_H -/* This is used for archs that do not support DMA */ +/* define the dma api to allow compilation but not linking of + * dma dependent code. Code that depends on the dma-mapping + * API needs to set 'depends on HAS_DMA' in its Kconfig + */ -static inline void * +struct scatterlist; + +extern void * dma_alloc_coherent(struct device *dev, size_t size, dma_addr_t *dma_handle, - gfp_t flag) -{ - BUG(); - return NULL; -} + gfp_t flag); -static inline void +extern void dma_free_coherent(struct device *dev, size_t size, void *cpu_addr, - dma_addr_t dma_handle) -{ - BUG(); -} + dma_addr_t dma_handle); #define dma_alloc_noncoherent(d, s, h, f) dma_alloc_coherent(d, s, h, f) #define dma_free_noncoherent(d, s, v, h) dma_free_coherent(d, s, v, h) +extern dma_addr_t +dma_map_single(struct device *dev, void *ptr, size_t size, + enum dma_data_direction direction); + +extern void +dma_unmap_single(struct device *dev, dma_addr_t dma_addr, size_t size, + enum dma_data_direction direction); + +extern int +dma_map_sg(struct device *dev, struct scatterlist *sg, int nents, + enum dma_data_direction direction); + +extern void +dma_unmap_sg(struct device *dev, struct scatterlist *sg, int nhwentries, + enum dma_data_direction direction); + +extern dma_addr_t +dma_map_page(struct device *dev, struct page *page, unsigned long offset, + size_t size, enum dma_data_direction direction); + +extern void +dma_unmap_page(struct device *dev, dma_addr_t dma_address, size_t size, + enum dma_data_direction direction); + +extern void +dma_sync_single_for_cpu(struct device *dev, dma_addr_t dma_handle, size_t size, + enum dma_data_direction direction); + +extern void +dma_sync_single_range_for_cpu(struct device *dev, dma_addr_t dma_handle, + unsigned long offset, size_t size, + enum dma_data_direction direction); + +extern void +dma_sync_sg_for_cpu(struct device *dev, struct scatterlist *sg, int nelems, + enum dma_data_direction direction); + +#define dma_sync_single_for_device dma_sync_single_for_cpu +#define dma_sync_single_range_for_device dma_sync_single_range_for_cpu +#define dma_sync_sg_for_device dma_sync_sg_for_cpu + +extern int +dma_mapping_error(dma_addr_t dma_addr); + +extern int +dma_supported(struct device *dev, u64 mask); + +extern int +dma_set_mask(struct device *dev, u64 mask); + +extern int +dma_get_cache_alignment(void); + +extern int +dma_is_consistent(struct device *dev, dma_addr_t dma_handle); + +extern void +dma_cache_sync(struct device *dev, void *vaddr, size_t size, + enum dma_data_direction direction); + #endif /* _ASM_GENERIC_DMA_MAPPING_H */ diff -puN include/asm-h8300/dma-mapping.h~dma-mapping-prevent-dma-dependent-code-from-linking-on /dev/null --- a/include/asm-h8300/dma-mapping.h +++ /dev/null @@ -1 +0,0 @@ -#include diff -puN include/asm-m32r/dma-mapping.h~dma-mapping-prevent-dma-dependent-code-from-linking-on /dev/null --- a/include/asm-m32r/dma-mapping.h +++ /dev/null @@ -1,6 +0,0 @@ -#ifndef _ASM_M32R_DMA_MAPPING_H -#define _ASM_M32R_DMA_MAPPING_H - -#include - -#endif /* _ASM_M32R_DMA_MAPPING_H */ diff -puN include/asm-s390/dma-mapping.h~dma-mapping-prevent-dma-dependent-code-from-linking-on /dev/null --- a/include/asm-s390/dma-mapping.h +++ /dev/null @@ -1,12 +0,0 @@ -/* - * include/asm-s390/dma-mapping.h - * - * S390 version - * - * This file exists so that #include doesn't break anything. - */ - -#ifndef _ASM_DMA_MAPPING_H -#define _ASM_DMA_MAPPING_H - -#endif /* _ASM_DMA_MAPPING_H */ diff -puN include/linux/dma-mapping.h~dma-mapping-prevent-dma-dependent-code-from-linking-on include/linux/dma-mapping.h --- a/include/linux/dma-mapping.h~dma-mapping-prevent-dma-dependent-code-from-linking-on +++ a/include/linux/dma-mapping.h @@ -31,7 +31,11 @@ static inline int valid_dma_direction(in (dma_direction == DMA_FROM_DEVICE)); } +#ifdef CONFIG_HAS_DMA #include +#else +#include +#endif /* Backwards compat, remove in 2.7.x */ #define dma_sync_single dma_sync_single_for_cpu _