[PATCH 24/34] dma-direct: rename dma_noop to dma_direct

Christoph Hellwig
2018-01-12T08:42:22Z

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 <hch@lst.de>
Reviewed-by: Vladimir Murzin <vladimir.murzin@arm.com>
---
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} (52%)

diff --git a/MAINTAINERS b/MAINTAINERS
index 234e642e7149..2d54e636d625 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -4334,7 +4334,7 @@ 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 6db5fc26d154..4d8042521e89 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);
@@ -213,7 +213,7 @@ 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 d67742dad904..b626028a3e47 100644
--- a/include/linux/dma-mapping.h
+++ b/include/linux/dma-mapping.h
@@ -136,7 +136,7 @@ struct dma_map_ops {
int 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 52%
rename from lib/dma-noop.c
rename to lib/dma-direct.c
index a10185b0c2d4..0ec3262a3148 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;
@@ -58,11 +54,10 @@ 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,
};
-
-EXPORT_SYMBOL(dma_noop_ops);
+EXPORT_SYMBOL(dma_direct_ops);
--
2.14.2