The trivial direct mapping implementation already does a virtual to physical translation which isn't strictly a noop, and will soon learn to do non-direct but linear physical to dma translations through the device offset and a few small tricks. Rename it to a better fitting name.
Signed-off-by: Christoph Hellwig <h...@lst.de> --- MAINTAINERS | 2 +- arch/arm/Kconfig | 2 +- arch/arm/include/asm/dma-mapping.h | 2 +- arch/arm/mm/dma-mapping-nommu.c | 8 ++++---- arch/m32r/Kconfig | 2 +- arch/riscv/Kconfig | 2 +- arch/s390/Kconfig | 2 +- include/asm-generic/dma-mapping.h | 2 +- include/linux/dma-mapping.h | 2 +- lib/Kconfig | 2 +- lib/Makefile | 2 +- lib/{dma-noop.c => dma-direct.c} | 35 +++++++++++++++-------------------- 12 files changed, 29 insertions(+), 34 deletions(-) rename lib/{dma-noop.c => dma-direct.c} (53%) diff --git a/MAINTAINERS b/MAINTAINERS index a8b35d9f41b2..b4005fe06e4c 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -4336,7 +4336,7 @@ T: git git://git.infradead.org/users/hch/dma-mapping.git W: http://git.infradead.org/users/hch/dma-mapping.git S: Supported F: lib/dma-debug.c -F: lib/dma-noop.c +F: lib/dma-direct.c F: lib/dma-virt.c F: drivers/base/dma-mapping.c F: drivers/base/dma-coherent.c diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index 00d889a37965..430a0aa710d6 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -25,7 +25,7 @@ config ARM select CLONE_BACKWARDS select CPU_PM if (SUSPEND || CPU_IDLE) select DCACHE_WORD_ACCESS if HAVE_EFFICIENT_UNALIGNED_ACCESS - select DMA_NOOP_OPS if !MMU + select DMA_DIRECT_OPS if !MMU select EDAC_SUPPORT select EDAC_ATOMIC_SCRUB select GENERIC_ALLOCATOR diff --git a/arch/arm/include/asm/dma-mapping.h b/arch/arm/include/asm/dma-mapping.h index e5d9020c9ee1..8436f6ade57d 100644 --- a/arch/arm/include/asm/dma-mapping.h +++ b/arch/arm/include/asm/dma-mapping.h @@ -18,7 +18,7 @@ extern const struct dma_map_ops arm_coherent_dma_ops; static inline const struct dma_map_ops *get_arch_dma_ops(struct bus_type *bus) { - return IS_ENABLED(CONFIG_MMU) ? &arm_dma_ops : &dma_noop_ops; + return IS_ENABLED(CONFIG_MMU) ? &arm_dma_ops : &dma_direct_ops; } #ifdef __arch_page_to_dma diff --git a/arch/arm/mm/dma-mapping-nommu.c b/arch/arm/mm/dma-mapping-nommu.c index 1cced700e45a..49e9831dc0f1 100644 --- a/arch/arm/mm/dma-mapping-nommu.c +++ b/arch/arm/mm/dma-mapping-nommu.c @@ -22,7 +22,7 @@ #include "dma.h" /* - * dma_noop_ops is used if + * dma_direct_ops is used if * - MMU/MPU is off * - cpu is v7m w/o cache support * - device is coherent @@ -39,7 +39,7 @@ static void *arm_nommu_dma_alloc(struct device *dev, size_t size, unsigned long attrs) { - const struct dma_map_ops *ops = &dma_noop_ops; + const struct dma_map_ops *ops = &dma_direct_ops; void *ret; /* @@ -70,7 +70,7 @@ static void arm_nommu_dma_free(struct device *dev, size_t size, void *cpu_addr, dma_addr_t dma_addr, unsigned long attrs) { - const struct dma_map_ops *ops = &dma_noop_ops; + const struct dma_map_ops *ops = &dma_direct_ops; if (attrs & DMA_ATTR_NON_CONSISTENT) { ops->free(dev, size, cpu_addr, dma_addr, attrs); @@ -214,7 +214,7 @@ EXPORT_SYMBOL(arm_nommu_dma_ops); static const struct dma_map_ops *arm_nommu_get_dma_map_ops(bool coherent) { - return coherent ? &dma_noop_ops : &arm_nommu_dma_ops; + return coherent ? &dma_direct_ops : &arm_nommu_dma_ops; } void arch_setup_dma_ops(struct device *dev, u64 dma_base, u64 size, diff --git a/arch/m32r/Kconfig b/arch/m32r/Kconfig index 498398d915c1..dd84ee194579 100644 --- a/arch/m32r/Kconfig +++ b/arch/m32r/Kconfig @@ -19,7 +19,7 @@ config M32R select MODULES_USE_ELF_RELA select HAVE_DEBUG_STACKOVERFLOW select CPU_NO_EFFICIENT_FFS - select DMA_NOOP_OPS + select DMA_DIRECT_OPS select ARCH_NO_COHERENT_DMA_MMAP if !MMU config SBUS diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig index 2c6adf12713a..865e14f50c14 100644 --- a/arch/riscv/Kconfig +++ b/arch/riscv/Kconfig @@ -83,7 +83,7 @@ config PGTABLE_LEVELS config HAVE_KPROBES def_bool n -config DMA_NOOP_OPS +config DMA_DIRECT_OPS def_bool y menu "Platform type" diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig index 829c67986db7..9376637229c9 100644 --- a/arch/s390/Kconfig +++ b/arch/s390/Kconfig @@ -140,7 +140,7 @@ config S390 select HAVE_DEBUG_KMEMLEAK select HAVE_DMA_API_DEBUG select HAVE_DMA_CONTIGUOUS - select DMA_NOOP_OPS + select DMA_DIRECT_OPS select HAVE_DYNAMIC_FTRACE select HAVE_DYNAMIC_FTRACE_WITH_REGS select HAVE_EFFICIENT_UNALIGNED_ACCESS diff --git a/include/asm-generic/dma-mapping.h b/include/asm-generic/dma-mapping.h index 164031531d85..880a292d792f 100644 --- a/include/asm-generic/dma-mapping.h +++ b/include/asm-generic/dma-mapping.h @@ -4,7 +4,7 @@ static inline const struct dma_map_ops *get_arch_dma_ops(struct bus_type *bus) { - return &dma_noop_ops; + return &dma_direct_ops; } #endif /* _ASM_GENERIC_DMA_MAPPING_H */ diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h index 72568bf4fc12..ff3528de5322 100644 --- a/include/linux/dma-mapping.h +++ b/include/linux/dma-mapping.h @@ -143,7 +143,7 @@ struct dma_map_ops { bool is_phys; }; -extern const struct dma_map_ops dma_noop_ops; +extern const struct dma_map_ops dma_direct_ops; extern const struct dma_map_ops dma_virt_ops; #define DMA_BIT_MASK(n) (((n) == 64) ? ~0ULL : ((1ULL<<(n))-1)) diff --git a/lib/Kconfig b/lib/Kconfig index c5e84fbcb30b..9d3d649c9dc9 100644 --- a/lib/Kconfig +++ b/lib/Kconfig @@ -409,7 +409,7 @@ config HAS_DMA depends on !NO_DMA default y -config DMA_NOOP_OPS +config DMA_DIRECT_OPS bool depends on HAS_DMA && (!64BIT || ARCH_DMA_ADDR_T_64BIT) default n diff --git a/lib/Makefile b/lib/Makefile index d11c48ec8ffd..749851abe85a 100644 --- a/lib/Makefile +++ b/lib/Makefile @@ -28,7 +28,7 @@ lib-y := ctype.o string.o vsprintf.o cmdline.o \ lib-$(CONFIG_MMU) += ioremap.o lib-$(CONFIG_SMP) += cpumask.o -lib-$(CONFIG_DMA_NOOP_OPS) += dma-noop.o +lib-$(CONFIG_DMA_DIRECT_OPS) += dma-direct.o lib-$(CONFIG_DMA_VIRT_OPS) += dma-virt.o lib-y += kobject.o klist.o diff --git a/lib/dma-noop.c b/lib/dma-direct.c similarity index 53% rename from lib/dma-noop.c rename to lib/dma-direct.c index c3728a0551f5..439db40854b7 100644 --- a/lib/dma-noop.c +++ b/lib/dma-direct.c @@ -10,9 +10,8 @@ #include <linux/scatterlist.h> #include <linux/pfn.h> -static void *dma_noop_alloc(struct device *dev, size_t size, - dma_addr_t *dma_handle, gfp_t gfp, - unsigned long attrs) +static void *dma_direct_alloc(struct device *dev, size_t size, + dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs) { void *ret; @@ -23,24 +22,21 @@ static void *dma_noop_alloc(struct device *dev, size_t size, return ret; } -static void dma_noop_free(struct device *dev, size_t size, - void *cpu_addr, dma_addr_t dma_addr, - unsigned long attrs) +static void dma_direct_free(struct device *dev, size_t size, void *cpu_addr, + dma_addr_t dma_addr, unsigned long attrs) { free_pages((unsigned long)cpu_addr, get_order(size)); } -static dma_addr_t dma_noop_map_page(struct device *dev, struct page *page, - unsigned long offset, size_t size, - enum dma_data_direction dir, - unsigned long attrs) +static dma_addr_t dma_direct_map_page(struct device *dev, struct page *page, + unsigned long offset, size_t size, enum dma_data_direction dir, + unsigned long attrs) { return page_to_phys(page) + offset - PFN_PHYS(dev->dma_pfn_offset); } -static int dma_noop_map_sg(struct device *dev, struct scatterlist *sgl, int nents, - enum dma_data_direction dir, - unsigned long attrs) +static int dma_direct_map_sg(struct device *dev, struct scatterlist *sgl, + int nents, enum dma_data_direction dir, unsigned long attrs) { int i; struct scatterlist *sg; @@ -58,12 +54,11 @@ static int dma_noop_map_sg(struct device *dev, struct scatterlist *sgl, int nent return nents; } -const struct dma_map_ops dma_noop_ops = { - .alloc = dma_noop_alloc, - .free = dma_noop_free, - .map_page = dma_noop_map_page, - .map_sg = dma_noop_map_sg, +const struct dma_map_ops dma_direct_ops = { + .alloc = dma_direct_alloc, + .free = dma_direct_free, + .map_page = dma_direct_map_page, + .map_sg = dma_direct_map_sg, .is_phys = true, }; - -EXPORT_SYMBOL(dma_noop_ops); +EXPORT_SYMBOL(dma_direct_ops); -- 2.14.2