dma-direct: rename dma_noop to dma_direct

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>

diff --git a/MAINTAINERS b/MAINTAINERS
index 234e642e71498ea05d2da42e3cbb4b0baf19d712..2d54e636d6258efff7e0938ef77c9723d1aa6e60 100644 (file)
--- 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 00d889a379657eb93fdafb39bde8a97d4f0639f8..430a0aa710d6c0cdf4aa4ce6abf246fc9bf7eb32 100644 (file)
--- 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 e5d9020c9ee18db7d07d5cc0c57f4e10c959d764..8436f6ade57dd145a717c11aa5207854a68c25a0 100644 (file)
--- 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 6db5fc26d154c6febf6d61c0bdf66aae9c563f9e..4d8042521e8940aa00f8f9f0e410f455fb4776b0 100644 (file)
--- 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 498398d915c1d46b6d3c83429bd8bc25c7255b67..dd84ee194579f8110751043ffe2e65120b6a53a4 100644 (file)
--- 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 2c6adf12713ad1ca5ab0b207add5c02457fb1545..865e14f50c144718a523b9ce0342f5675f4c9db8 100644 (file)
--- 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 829c67986db7742f3d95a69ed35600fc41e75c55..9376637229c94bef154ee5d538665ce76d11bce9 100644 (file)
--- 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 164031531d85479bf86f920b974a3c4733bd4821..880a292d792fbab4f576a57d7dc31f082e28332b 100644 (file)
--- 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 46542ad9d709286efd4b12ea3ff18a47bb9deac7..34fe8463d10ea3be5df5fb27d80c51d663b94136 100644 (file)
--- 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 c5e84fbcb30b7562656dcbbc050bcc0ec4cb7a90..9d3d649c9dc90f7b56d8692b1bf1d2b8fc9b5153 100644 (file)
--- 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 d11c48ec8ffdbd32db32cf9258c8bb45e92e440b..749851abe85abb85cf23166fd13985f66a23f808 100644 (file)
--- 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-direct.c b/lib/dma-direct.c
new file mode 100644 (file)
index 0000000..0ec3262
--- /dev/null
+++ b/lib/dma-direct.c
@@ -0,0 +1,63 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ *     lib/dma-noop.c
+ *
+ * DMA operations that map to physical addresses without flushing memory.
+ */
+#include <linux/export.h>
+#include <linux/mm.h>
+#include <linux/dma-mapping.h>
+#include <linux/scatterlist.h>
+#include <linux/pfn.h>
+
+static void *dma_direct_alloc(struct device *dev, size_t size,
+               dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs)
+{
+       void *ret;
+
+       ret = (void *)__get_free_pages(gfp, get_order(size));
+       if (ret)
+               *dma_handle = virt_to_phys(ret) - PFN_PHYS(dev->dma_pfn_offset);
+
+       return ret;
+}
+
+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_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_direct_map_sg(struct device *dev, struct scatterlist *sgl,
+               int nents, enum dma_data_direction dir, unsigned long attrs)
+{
+       int i;
+       struct scatterlist *sg;
+
+       for_each_sg(sgl, sg, nents, i) {
+               dma_addr_t offset = PFN_PHYS(dev->dma_pfn_offset);
+               void *va;
+
+               BUG_ON(!sg_page(sg));
+               va = sg_virt(sg);
+               sg_dma_address(sg) = (dma_addr_t)virt_to_phys(va) - offset;
+               sg_dma_len(sg) = sg->length;
+       }
+
+       return nents;
+}
+
+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_direct_ops);

diff --git a/lib/dma-noop.c b/lib/dma-noop.c
deleted file mode 100644 (file)
index a10185b..0000000
--- a/lib/dma-noop.c
+++ /dev/null
@@ -1,68 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-/*
- *     lib/dma-noop.c
- *
- * DMA operations that map to physical addresses without flushing memory.
- */
-#include <linux/export.h>
-#include <linux/mm.h>
-#include <linux/dma-mapping.h>
-#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)
-{
-       void *ret;
-
-       ret = (void *)__get_free_pages(gfp, get_order(size));
-       if (ret)
-               *dma_handle = virt_to_phys(ret) - PFN_PHYS(dev->dma_pfn_offset);
-
-       return ret;
-}
-
-static void dma_noop_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)
-{
-       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)
-{
-       int i;
-       struct scatterlist *sg;
-
-       for_each_sg(sgl, sg, nents, i) {
-               dma_addr_t offset = PFN_PHYS(dev->dma_pfn_offset);
-               void *va;
-
-               BUG_ON(!sg_page(sg));
-               va = sg_virt(sg);
-               sg_dma_address(sg) = (dma_addr_t)virt_to_phys(va) - offset;
-               sg_dma_len(sg) = sg->length;
-       }
-
-       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,
-};
-
-EXPORT_SYMBOL(dma_noop_ops);