[PATCH] dma-mapping: no need to pass a bus_type into get_arch_dma_ops()

[PATCH] dma-mapping: no need to pass a bus_type into get_arch_dma_ops()

[Greg Kroah-Hartman]

The get_arch_dma_ops() arch-specific function never does anything with
the struct bus_type that is passed into it, so remove it entirely as it
is not needed.

Cc: Richard Henderson <richard.henderson@linaro.org>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Helge Deller <deller@gmx.de>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: x86@kernel.org
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Robin Murphy <robin.murphy@arm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: linux-alpha@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-ia64@vger.kernel.org
Cc: linux-mips@vger.kernel.org
Cc: linux-parisc@vger.kernel.org
Cc: sparclinux@vger.kernel.org
Cc: iommu@lists.linux.dev
Cc: linux-arch@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
Note: Unless someone objects, I would like to take this through the
driver-core tree, as further bus_type cleanups depend on it, and it's
stand-alone from everyone else's tree at the moment from what I can
determine.

 arch/alpha/include/asm/dma-mapping.h  | 2 +-
 arch/ia64/include/asm/dma-mapping.h   | 2 +-
 arch/mips/include/asm/dma-mapping.h   | 2 +-
 arch/parisc/include/asm/dma-mapping.h | 2 +-
 arch/sparc/include/asm/dma-mapping.h  | 2 +-
 arch/x86/include/asm/dma-mapping.h    | 2 +-
 include/asm-generic/dma-mapping.h     | 2 +-
 include/linux/dma-map-ops.h           | 2 +-
 8 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/arch/alpha/include/asm/dma-mapping.h b/arch/alpha/include/asm/dma-mapping.h
index 0ee6a5c99b16..6ce7e2041685 100644
--- a/arch/alpha/include/asm/dma-mapping.h
+++ b/arch/alpha/include/asm/dma-mapping.h
@@ -4,7 +4,7 @@
 
 extern const struct dma_map_ops alpha_pci_ops;
 
-static inline const struct dma_map_ops *get_arch_dma_ops(struct bus_type *bus)
+static inline const struct dma_map_ops *get_arch_dma_ops(void)
 {
 #ifdef CONFIG_ALPHA_JENSEN
 	return NULL;
diff --git a/arch/ia64/include/asm/dma-mapping.h b/arch/ia64/include/asm/dma-mapping.h
index a5d9d788eede..af6fa8e1597c 100644
--- a/arch/ia64/include/asm/dma-mapping.h
+++ b/arch/ia64/include/asm/dma-mapping.h
@@ -8,7 +8,7 @@
  */
 extern const struct dma_map_ops *dma_ops;
 
-static inline const struct dma_map_ops *get_arch_dma_ops(struct bus_type *bus)
+static inline const struct dma_map_ops *get_arch_dma_ops(void)
 {
 	return dma_ops;
 }
diff --git a/arch/mips/include/asm/dma-mapping.h b/arch/mips/include/asm/dma-mapping.h
index 34de7b17b41b..0fee561ac796 100644
--- a/arch/mips/include/asm/dma-mapping.h
+++ b/arch/mips/include/asm/dma-mapping.h
@@ -6,7 +6,7 @@
 
 extern const struct dma_map_ops jazz_dma_ops;
 
-static inline const struct dma_map_ops *get_arch_dma_ops(struct bus_type *bus)
+static inline const struct dma_map_ops *get_arch_dma_ops(void)
 {
 #if defined(CONFIG_MACH_JAZZ)
 	return &jazz_dma_ops;
diff --git a/arch/parisc/include/asm/dma-mapping.h b/arch/parisc/include/asm/dma-mapping.h
index d5bd94247371..635665004fe6 100644
--- a/arch/parisc/include/asm/dma-mapping.h
+++ b/arch/parisc/include/asm/dma-mapping.h
@@ -21,7 +21,7 @@
 
 extern const struct dma_map_ops *hppa_dma_ops;
 
-static inline const struct dma_map_ops *get_arch_dma_ops(struct bus_type *bus)
+static inline const struct dma_map_ops *get_arch_dma_ops(void)
 {
 	return hppa_dma_ops;
 }
diff --git a/arch/sparc/include/asm/dma-mapping.h b/arch/sparc/include/asm/dma-mapping.h
index 2f051343612e..55c12fc2ba63 100644
--- a/arch/sparc/include/asm/dma-mapping.h
+++ b/arch/sparc/include/asm/dma-mapping.h
@@ -4,7 +4,7 @@
 
 extern const struct dma_map_ops *dma_ops;
 
-static inline const struct dma_map_ops *get_arch_dma_ops(struct bus_type *bus)
+static inline const struct dma_map_ops *get_arch_dma_ops(void)
 {
 	/* sparc32 uses per-device dma_ops */
 	return IS_ENABLED(CONFIG_SPARC64) ? dma_ops : NULL;
diff --git a/arch/x86/include/asm/dma-mapping.h b/arch/x86/include/asm/dma-mapping.h
index 1c66708e3062..d1dac96ee30b 100644
--- a/arch/x86/include/asm/dma-mapping.h
+++ b/arch/x86/include/asm/dma-mapping.h
@@ -4,7 +4,7 @@
 
 extern const struct dma_map_ops *dma_ops;
 
-static inline const struct dma_map_ops *get_arch_dma_ops(struct bus_type *bus)
+static inline const struct dma_map_ops *get_arch_dma_ops(void)
 {
 	return dma_ops;
 }
diff --git a/include/asm-generic/dma-mapping.h b/include/asm-generic/dma-mapping.h
index c13f46109e88..46a0016efd81 100644
--- a/include/asm-generic/dma-mapping.h
+++ b/include/asm-generic/dma-mapping.h
@@ -2,7 +2,7 @@
 #ifndef _ASM_GENERIC_DMA_MAPPING_H
 #define _ASM_GENERIC_DMA_MAPPING_H
 
-static inline const struct dma_map_ops *get_arch_dma_ops(struct bus_type *bus)
+static inline const struct dma_map_ops *get_arch_dma_ops(void)
 {
 	return NULL;
 }
diff --git a/include/linux/dma-map-ops.h b/include/linux/dma-map-ops.h
index d678afeb8a13..41bf4bdb117a 100644
--- a/include/linux/dma-map-ops.h
+++ b/include/linux/dma-map-ops.h
@@ -90,7 +90,7 @@ static inline const struct dma_map_ops *get_dma_ops(struct device *dev)
 {
 	if (dev->dma_ops)
 		return dev->dma_ops;
-	return get_arch_dma_ops(dev->bus);
+	return get_arch_dma_ops();
 }
 
 static inline void set_dma_ops(struct device *dev,
-- 
2.39.1

Re: [PATCH] dma-mapping: no need to pass a bus_type into get_arch_dma_ops()

[Christoph Hellwig]

On Tue, Feb 14, 2023 at 03:01:21PM +0100, Greg Kroah-Hartman wrote:
> The get_arch_dma_ops() arch-specific function never does anything with
> the struct bus_type that is passed into it, so remove it entirely as it
> is not needed.

Yes.  (and eventually get_arch_dma_ops should go away entirely, but that's
a separate story).

> Note: Unless someone objects, I would like to take this through the
> driver-core tree, as further bus_type cleanups depend on it, and it's
> stand-alone from everyone else's tree at the moment from what I can
> determine.

Please do!

Acked-by: Christoph Hellwig <hch@lst.de>

Re: [PATCH] dma-mapping: no need to pass a bus_type into get_arch_dma_ops()

[Arnd Bergmann]

On Tue, Feb 14, 2023, at 15:01, Greg Kroah-Hartman wrote:
> The get_arch_dma_ops() arch-specific function never does anything with
> the struct bus_type that is passed into it, so remove it entirely as it
> is not needed.
> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> ---
> Note: Unless someone objects, I would like to take this through the
> driver-core tree, as further bus_type cleanups depend on it, and it's
> stand-alone from everyone else's tree at the moment from what I can
> determine.

Nice find!

Reviewed-by: Arnd Bergmann <arnd@arndb.de>

It looks like the bus was last required in 2020 before commit
255a69a94b8c ("sparc32: use per-device dma_ops").

    Arnd