[PATCH v2 01/10] m68k: use for_each_sg()

[PATCH v2 01/10] m68k: use for_each_sg()

[Akinobu Mita]

This replaces the plain loop over the sglist array with for_each_sg()
macro which consists of sg_next() function calls.  Since m68k doesn't
select ARCH_HAS_SG_CHAIN, it is not necessary to use for_each_sg() in
order to loop over each sg element.  But this can help find problems
with drivers that do not properly initialize their sg tables when
CONFIG_DEBUG_SG is enabled.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: linux-m68k@lists.linux-m68k.org
Cc: linux-arch@vger.kernel.org
---
* Changes from v1
- Update commit log

 arch/m68k/kernel/dma.c | 19 ++++++++++++-------
 1 file changed, 12 insertions(+), 7 deletions(-)

diff --git a/arch/m68k/kernel/dma.c b/arch/m68k/kernel/dma.c
index e546a55..564665f 100644
--- a/arch/m68k/kernel/dma.c
+++ b/arch/m68k/kernel/dma.c
@@ -120,13 +120,16 @@ void dma_sync_single_for_device(struct device *dev, dma_addr_t handle,
 }
 EXPORT_SYMBOL(dma_sync_single_for_device);
 
-void dma_sync_sg_for_device(struct device *dev, struct scatterlist *sg, int nents,
-			    enum dma_data_direction dir)
+void dma_sync_sg_for_device(struct device *dev, struct scatterlist *sglist,
+			    int nents, enum dma_data_direction dir)
 {
 	int i;
+	struct scatterlist *sg;
 
-	for (i = 0; i < nents; sg++, i++)
-		dma_sync_single_for_device(dev, sg->dma_address, sg->length, dir);
+	for_each_sg(sglist, sg, nents, i) {
+		dma_sync_single_for_device(dev, sg->dma_address, sg->length,
+					   dir);
+	}
 }
 EXPORT_SYMBOL(dma_sync_sg_for_device);
 
@@ -151,14 +154,16 @@ dma_addr_t dma_map_page(struct device *dev, struct page *page,
 }
 EXPORT_SYMBOL(dma_map_page);
 
-int dma_map_sg(struct device *dev, struct scatterlist *sg, int nents,
+int dma_map_sg(struct device *dev, struct scatterlist *sglist, int nents,
 	       enum dma_data_direction dir)
 {
 	int i;
+	struct scatterlist *sg;
 
-	for (i = 0; i < nents; sg++, i++) {
+	for_each_sg(sglist, sg, nents, i) {
 		sg->dma_address = sg_phys(sg);
-		dma_sync_single_for_device(dev, sg->dma_address, sg->length, dir);
+		dma_sync_single_for_device(dev, sg->dma_address, sg->length,
+					   dir);
 	}
 	return nents;
 }
-- 
1.9.1

[PATCH v2 02/10] arc: use for_each_sg()

[Akinobu Mita]

This replaces the plain loop over the sglist array with for_each_sg()
macro which consists of sg_next() function calls.  Since arc doesn't
select ARCH_HAS_SG_CHAIN, it is not necessary to use for_each_sg() in
order to loop over each sg element.  But this can help find problems
with drivers that do not properly initialize their sg tables when
CONFIG_DEBUG_SG is enabled.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Acked-by: Vineet Gupta <vgupta@synopsys.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: linux-arch@vger.kernel.org
---
* Changes from v1
- Update commit log

 arch/arc/include/asm/dma-mapping.h | 12 +++++++-----
 1 file changed, 7 insertions(+), 5 deletions(-)

diff --git a/arch/arc/include/asm/dma-mapping.h b/arch/arc/include/asm/dma-mapping.h
index 45b8e0c..f787894 100644
--- a/arch/arc/include/asm/dma-mapping.h
+++ b/arch/arc/include/asm/dma-mapping.h
@@ -178,22 +178,24 @@ dma_sync_single_range_for_device(struct device *dev, dma_addr_t dma_handle,
 }
 
 static inline void
-dma_sync_sg_for_cpu(struct device *dev, struct scatterlist *sg, int nelems,
+dma_sync_sg_for_cpu(struct device *dev, struct scatterlist *sglist, int nelems,
 		    enum dma_data_direction dir)
 {
 	int i;
+	struct scatterlist *sg;
 
-	for (i = 0; i < nelems; i++, sg++)
+	for_each_sg(sglist, sg, nelems, i)
 		_dma_cache_sync((unsigned int)sg_virt(sg), sg->length, dir);
 }
 
 static inline void
-dma_sync_sg_for_device(struct device *dev, struct scatterlist *sg, int nelems,
-		       enum dma_data_direction dir)
+dma_sync_sg_for_device(struct device *dev, struct scatterlist *sglist,
+		       int nelems, enum dma_data_direction dir)
 {
 	int i;
+	struct scatterlist *sg;
 
-	for (i = 0; i < nelems; i++, sg++)
+	for_each_sg(sglist, sg, nelems, i)
 		_dma_cache_sync((unsigned int)sg_virt(sg), sg->length, dir);
 }
 
-- 
1.9.1

[PATCH v2 03/10] metag: use for_each_sg()

[Akinobu Mita]

This replaces the plain loop over the sglist array with for_each_sg()
macro which consists of sg_next() function calls.  Since metag doesn't
select ARCH_HAS_SG_CHAIN, it is not necessary to use for_each_sg() in
order to loop over each sg element.  But this can help find problems
with drivers that do not properly initialize their sg tables when
CONFIG_DEBUG_SG is enabled.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: linux-metag@vger.kernel.org
Cc: linux-arch@vger.kernel.org
---
* Changes from v1
- Update commit log

 arch/metag/include/asm/dma-mapping.h | 14 +++++++++-----
 1 file changed, 9 insertions(+), 5 deletions(-)

diff --git a/arch/metag/include/asm/dma-mapping.h b/arch/metag/include/asm/dma-mapping.h
index 14b23ef..eb5cdec 100644
--- a/arch/metag/include/asm/dma-mapping.h
+++ b/arch/metag/include/asm/dma-mapping.h
@@ -134,20 +134,24 @@ dma_sync_single_range_for_device(struct device *dev, dma_addr_t dma_handle,
 }
 
 static inline void
-dma_sync_sg_for_cpu(struct device *dev, struct scatterlist *sg, int nelems,
+dma_sync_sg_for_cpu(struct device *dev, struct scatterlist *sglist, int nelems,
 		    enum dma_data_direction direction)
 {
 	int i;
-	for (i = 0; i < nelems; i++, sg++)
+	struct scatterlist *sg;
+
+	for_each_sg(sglist, sg, nelems, i)
 		dma_sync_for_cpu(sg_virt(sg), sg->length, direction);
 }
 
 static inline void
-dma_sync_sg_for_device(struct device *dev, struct scatterlist *sg, int nelems,
-		       enum dma_data_direction direction)
+dma_sync_sg_for_device(struct device *dev, struct scatterlist *sglist,
+		       int nelems, enum dma_data_direction direction)
 {
 	int i;
-	for (i = 0; i < nelems; i++, sg++)
+	struct scatterlist *sg;
+
+	for_each_sg(sglist, sg, nelems, i)
 		dma_sync_for_device(sg_virt(sg), sg->length, direction);
 }
 
-- 
1.9.1

[PATCH v2 04/10] xtensa: use for_each_sg()

[Akinobu Mita]

This replaces the plain loop over the sglist array with for_each_sg()
macro which consists of sg_next() function calls.  Since xtensa doesn't
select ARCH_HAS_SG_CHAIN, it is not necessary to use for_each_sg() in
order to loop over each sg element.  But this can help find problems
with drivers that do not properly initialize their sg tables when
CONFIG_DEBUG_SG is enabled.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: linux-xtensa@linux-xtensa.org
Cc: linux-arch@vger.kernel.org
---
* Changes from v1
- Update commit log

 arch/xtensa/include/asm/dma-mapping.h | 19 ++++++++++++-------
 1 file changed, 12 insertions(+), 7 deletions(-)

diff --git a/arch/xtensa/include/asm/dma-mapping.h b/arch/xtensa/include/asm/dma-mapping.h
index 172a02a..54d2b22 100644
--- a/arch/xtensa/include/asm/dma-mapping.h
+++ b/arch/xtensa/include/asm/dma-mapping.h
@@ -52,14 +52,15 @@ dma_unmap_single(struct device *dev, dma_addr_t dma_addr, size_t size,
 }
 
 static inline int
-dma_map_sg(struct device *dev, struct scatterlist *sg, int nents,
+dma_map_sg(struct device *dev, struct scatterlist *sglist, int nents,
 	   enum dma_data_direction direction)
 {
 	int i;
+	struct scatterlist *sg;
 
 	BUG_ON(direction == DMA_NONE);
 
-	for (i = 0; i < nents; i++, sg++ ) {
+	for_each_sg(sglist, sg, nents, i) {
 		BUG_ON(!sg_page(sg));
 
 		sg->dma_address = sg_phys(sg);
@@ -124,20 +125,24 @@ dma_sync_single_range_for_device(struct device *dev, dma_addr_t dma_handle,
 	consistent_sync((void *)bus_to_virt(dma_handle)+offset,size,direction);
 }
 static inline void
-dma_sync_sg_for_cpu(struct device *dev, struct scatterlist *sg, int nelems,
+dma_sync_sg_for_cpu(struct device *dev, struct scatterlist *sglist, int nelems,
 		 enum dma_data_direction dir)
 {
 	int i;
-	for (i = 0; i < nelems; i++, sg++)
+	struct scatterlist *sg;
+
+	for_each_sg(sglist, sg, nelems, i)
 		consistent_sync(sg_virt(sg), sg->length, dir);
 }
 
 static inline void
-dma_sync_sg_for_device(struct device *dev, struct scatterlist *sg, int nelems,
-		 enum dma_data_direction dir)
+dma_sync_sg_for_device(struct device *dev, struct scatterlist *sglist,
+		       int nelems, enum dma_data_direction dir)
 {
 	int i;
-	for (i = 0; i < nelems; i++, sg++)
+	struct scatterlist *sg;
+
+	for_each_sg(sglist, sg, nelems, i)
 		consistent_sync(sg_virt(sg), sg->length, dir);
 }
 static inline int
-- 
1.9.1

[PATCH v2 05/10] mips: use for_each_sg()

[Akinobu Mita]

This replaces the plain loop over the sglist array with for_each_sg()
macro which consists of sg_next() function calls.  Since mips doesn't
select ARCH_HAS_SG_CHAIN, it is not necessary to use for_each_sg() in
order to loop over each sg element.  But this can help find problems
with drivers that do not properly initialize their sg tables when
CONFIG_DEBUG_SG is enabled.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: linux-arch@vger.kernel.org
---
* Changes from v1
- Update commit log

 arch/mips/mm/dma-default.c | 30 ++++++++++++++++++++----------
 1 file changed, 20 insertions(+), 10 deletions(-)

diff --git a/arch/mips/mm/dma-default.c b/arch/mips/mm/dma-default.c
index 609d124..eeaf024 100644
--- a/arch/mips/mm/dma-default.c
+++ b/arch/mips/mm/dma-default.c
@@ -262,12 +262,13 @@ static void mips_dma_unmap_page(struct device *dev, dma_addr_t dma_addr,
 	plat_unmap_dma_mem(dev, dma_addr, size, direction);
 }
 
-static int mips_dma_map_sg(struct device *dev, struct scatterlist *sg,
+static int mips_dma_map_sg(struct device *dev, struct scatterlist *sglist,
 	int nents, enum dma_data_direction direction, struct dma_attrs *attrs)
 {
 	int i;
+	struct scatterlist *sg;
 
-	for (i = 0; i < nents; i++, sg++) {
+	for_each_sg(sglist, sg, nents, i) {
 		if (!plat_device_is_coherent(dev))
 			__dma_sync(sg_page(sg), sg->offset, sg->length,
 				   direction);
@@ -291,13 +292,14 @@ static dma_addr_t mips_dma_map_page(struct device *dev, struct page *page,
 	return plat_map_dma_mem_page(dev, page) + offset;
 }
 
-static void mips_dma_unmap_sg(struct device *dev, struct scatterlist *sg,
+static void mips_dma_unmap_sg(struct device *dev, struct scatterlist *sglist,
 	int nhwentries, enum dma_data_direction direction,
 	struct dma_attrs *attrs)
 {
 	int i;
+	struct scatterlist *sg;
 
-	for (i = 0; i < nhwentries; i++, sg++) {
+	for_each_sg(sglist, sg, nhwentries, i) {
 		if (!plat_device_is_coherent(dev) &&
 		    direction != DMA_TO_DEVICE)
 			__dma_sync(sg_page(sg), sg->offset, sg->length,
@@ -324,26 +326,34 @@ static void mips_dma_sync_single_for_device(struct device *dev,
 }
 
 static void mips_dma_sync_sg_for_cpu(struct device *dev,
-	struct scatterlist *sg, int nelems, enum dma_data_direction direction)
+	struct scatterlist *sglist, int nelems,
+	enum dma_data_direction direction)
 {
 	int i;
+	struct scatterlist *sg;
 
-	if (cpu_needs_post_dma_flush(dev))
-		for (i = 0; i < nelems; i++, sg++)
+	if (cpu_needs_post_dma_flush(dev)) {
+		for_each_sg(sglist, sg, nelems, i) {
 			__dma_sync(sg_page(sg), sg->offset, sg->length,
 				   direction);
+		}
+	}
 	plat_post_dma_flush(dev);
 }
 
 static void mips_dma_sync_sg_for_device(struct device *dev,
-	struct scatterlist *sg, int nelems, enum dma_data_direction direction)
+	struct scatterlist *sglist, int nelems,
+	enum dma_data_direction direction)
 {
 	int i;
+	struct scatterlist *sg;
 
-	if (!plat_device_is_coherent(dev))
-		for (i = 0; i < nelems; i++, sg++)
+	if (!plat_device_is_coherent(dev)) {
+		for_each_sg(sglist, sg, nelems, i) {
 			__dma_sync(sg_page(sg), sg->offset, sg->length,
 				   direction);
+		}
+	}
 }
 
 int mips_dma_mapping_error(struct device *dev, dma_addr_t dma_addr)
-- 
1.9.1

[PATCH v2 06/10] frv: use for_each_sg()

[Akinobu Mita]

This replaces the plain loop over the sglist array with for_each_sg()
macro which consists of sg_next() function calls.  Since frv doesn't
select ARCH_HAS_SG_CHAIN, it is not necessary to use for_each_sg() in
order to loop over each sg element.  But this can help find problems
with drivers that do not properly initialize their sg tables when
CONFIG_DEBUG_SG is enabled.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: David Howells <dhowells@redhat.com>
Cc: linux-arch@vger.kernel.org
---
* New patch from v2

 arch/frv/mb93090-mb00/pci-dma-nommu.c | 10 ++++++----
 arch/frv/mb93090-mb00/pci-dma.c       |  7 ++++---
 2 files changed, 10 insertions(+), 7 deletions(-)

diff --git a/arch/frv/mb93090-mb00/pci-dma-nommu.c b/arch/frv/mb93090-mb00/pci-dma-nommu.c
index b99c2a7..8eeea0d 100644
--- a/arch/frv/mb93090-mb00/pci-dma-nommu.c
+++ b/arch/frv/mb93090-mb00/pci-dma-nommu.c
@@ -119,14 +119,16 @@ dma_addr_t dma_map_single(struct device *dev, void *ptr, size_t size,
 
 EXPORT_SYMBOL(dma_map_single);
 
-int dma_map_sg(struct device *dev, struct scatterlist *sg, int nents,
+int dma_map_sg(struct device *dev, struct scatterlist *sglist, int nents,
 	       enum dma_data_direction direction)
 {
 	int i;
+	struct scatterlist *sg;
 
-	for (i=0; i<nents; i++)
-		frv_cache_wback_inv(sg_dma_address(&sg[i]),
-				    sg_dma_address(&sg[i]) + sg_dma_len(&sg[i]));
+	for_each_sg(sglist, sg, nents, i) {
+		frv_cache_wback_inv(sg_dma_address(sg),
+				    sg_dma_address(sg) + sg_dma_len(sg));
+	}
 
 	BUG_ON(direction == DMA_NONE);
 
diff --git a/arch/frv/mb93090-mb00/pci-dma.c b/arch/frv/mb93090-mb00/pci-dma.c
index 8247897..4d1f01d 100644
--- a/arch/frv/mb93090-mb00/pci-dma.c
+++ b/arch/frv/mb93090-mb00/pci-dma.c
@@ -50,19 +50,20 @@ dma_addr_t dma_map_single(struct device *dev, void *ptr, size_t size,
 
 EXPORT_SYMBOL(dma_map_single);
 
-int dma_map_sg(struct device *dev, struct scatterlist *sg, int nents,
+int dma_map_sg(struct device *dev, struct scatterlist *sglist, int nents,
 	       enum dma_data_direction direction)
 {
 	unsigned long dampr2;
 	void *vaddr;
 	int i;
+	struct scatterlist *sg;
 
 	BUG_ON(direction == DMA_NONE);
 
 	dampr2 = __get_DAMPR(2);
 
-	for (i = 0; i < nents; i++) {
-		vaddr = kmap_atomic_primary(sg_page(&sg[i]));
+	for_each_sg(sglist, sg, nents, i) {
+		vaddr = kmap_atomic_primary(sg_page(sg));
 
 		frv_dcache_writeback((unsigned long) vaddr,
 				     (unsigned long) vaddr + PAGE_SIZE);
-- 
1.9.1

[PATCH v2 07/10] avr32: use for_each_sg()

[Akinobu Mita]

This replaces the plain loop over the sglist array with for_each_sg()
macro which consists of sg_next() function calls.  Since avr32 doesn't
select ARCH_HAS_SG_CHAIN, it is not necessary to use for_each_sg() in
order to loop over each sg element.  But this can help find problems
with drivers that do not properly initialize their sg tables when
CONFIG_DEBUG_SG is enabled.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Haavard Skinnemoen <hskinnemoen@gmail.com>
Cc: Hans-Christian Egtvedt <egtvedt@samfundet.no>
Cc: linux-arch@vger.kernel.org
---
* New patch from v2

 arch/avr32/include/asm/dma-mapping.h | 19 ++++++++++---------
 1 file changed, 10 insertions(+), 9 deletions(-)

diff --git a/arch/avr32/include/asm/dma-mapping.h b/arch/avr32/include/asm/dma-mapping.h
index b3d18f9..ae7ac92 100644
--- a/arch/avr32/include/asm/dma-mapping.h
+++ b/arch/avr32/include/asm/dma-mapping.h
@@ -209,17 +209,18 @@ dma_unmap_page(struct device *dev, dma_addr_t dma_address, size_t size,
  * the same here.
  */
 static inline int
-dma_map_sg(struct device *dev, struct scatterlist *sg, int nents,
+dma_map_sg(struct device *dev, struct scatterlist *sglist, int nents,
 	   enum dma_data_direction direction)
 {
 	int i;
+	struct scatterlist *sg;
 
-	for (i = 0; i < nents; i++) {
+	for_each_sg(sglist, sg, nents, i) {
 		char *virt;
 
-		sg[i].dma_address = page_to_bus(sg_page(&sg[i])) + sg[i].offset;
-		virt = sg_virt(&sg[i]);
-		dma_cache_sync(dev, virt, sg[i].length, direction);
+		sg->dma_address = page_to_bus(sg_page(sg)) + sg->offset;
+		virt = sg_virt(sg);
+		dma_cache_sync(dev, virt, sg->length, direction);
 	}
 
 	return nents;
@@ -321,14 +322,14 @@ dma_sync_sg_for_cpu(struct device *dev, struct scatterlist *sg,
 }
 
 static inline void
-dma_sync_sg_for_device(struct device *dev, struct scatterlist *sg,
+dma_sync_sg_for_device(struct device *dev, struct scatterlist *sglist,
 		       int nents, enum dma_data_direction direction)
 {
 	int i;
+	struct scatterlist *sg;
 
-	for (i = 0; i < nents; i++) {
-		dma_cache_sync(dev, sg_virt(&sg[i]), sg[i].length, direction);
-	}
+	for_each_sg(sglist, sg, nents, i)
+		dma_cache_sync(dev, sg_virt(sg), sg->length, direction);
 }
 
 /* Now for the API extensions over the pci_ one */
-- 
1.9.1

Re: [PATCH v2 07/10] avr32: use for_each_sg()

[Hans-Christian Egtvedt]

Around Fri 01 May 2015 22:56:40 +0900 or thereabout, Akinobu Mita wrote:
> This replaces the plain loop over the sglist array with for_each_sg()
> macro which consists of sg_next() function calls.  Since avr32 doesn't
> select ARCH_HAS_SG_CHAIN, it is not necessary to use for_each_sg() in
> order to loop over each sg element.  But this can help find problems
> with drivers that do not properly initialize their sg tables when
> CONFIG_DEBUG_SG is enabled.

Nice

> Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
> Cc: Haavard Skinnemoen <hskinnemoen@gmail.com>
> Cc: Hans-Christian Egtvedt <egtvedt@samfundet.no>
> Cc: linux-arch@vger.kernel.org

Acked-by: Hans-Christian Egtvedt <egtvedt@samfundet.no>

> ---
> * New patch from v2
> 
>  arch/avr32/include/asm/dma-mapping.h | 19 ++++++++++---------
>  1 file changed, 10 insertions(+), 9 deletions(-)
> 
> diff --git a/arch/avr32/include/asm/dma-mapping.h b/arch/avr32/include/asm/dma-mapping.h
> index b3d18f9..ae7ac92 100644
> --- a/arch/avr32/include/asm/dma-mapping.h
> +++ b/arch/avr32/include/asm/dma-mapping.h
> @@ -209,17 +209,18 @@ dma_unmap_page(struct device *dev, dma_addr_t dma_address, size_t size,
>   * the same here.
>   */
>  static inline int
> -dma_map_sg(struct device *dev, struct scatterlist *sg, int nents,
> +dma_map_sg(struct device *dev, struct scatterlist *sglist, int nents,
>  	   enum dma_data_direction direction)
>  {
>  	int i;
> +	struct scatterlist *sg;
>  
> -	for (i = 0; i < nents; i++) {
> +	for_each_sg(sglist, sg, nents, i) {
>  		char *virt;
>  
> -		sg[i].dma_address = page_to_bus(sg_page(&sg[i])) + sg[i].offset;
> -		virt = sg_virt(&sg[i]);
> -		dma_cache_sync(dev, virt, sg[i].length, direction);
> +		sg->dma_address = page_to_bus(sg_page(sg)) + sg->offset;
> +		virt = sg_virt(sg);
> +		dma_cache_sync(dev, virt, sg->length, direction);
>  	}
>  
>  	return nents;
> @@ -321,14 +322,14 @@ dma_sync_sg_for_cpu(struct device *dev, struct scatterlist *sg,
>  }
>  
>  static inline void
> -dma_sync_sg_for_device(struct device *dev, struct scatterlist *sg,
> +dma_sync_sg_for_device(struct device *dev, struct scatterlist *sglist,
>  		       int nents, enum dma_data_direction direction)
>  {
>  	int i;
> +	struct scatterlist *sg;
>  
> -	for (i = 0; i < nents; i++) {
> -		dma_cache_sync(dev, sg_virt(&sg[i]), sg[i].length, direction);
> -	}
> +	for_each_sg(sglist, sg, nents, i)
> +		dma_cache_sync(dev, sg_virt(sg), sg->length, direction);
>  }
>  
>  /* Now for the API extensions over the pci_ one */
-- 
mvh
Hans-Christian Egtvedt

[PATCH v2 08/10] powerpc: use for_each_sg()

[Akinobu Mita]

This replaces the plain loop over the sglist array with for_each_sg()
macro which consists of sg_next() function calls.  Since powerpc does
select ARCH_HAS_SG_CHAIN, it is necessary to use for_each_sg() in
order to loop over each sg element.  This also help find problems with
drivers that do not properly initialize their sg tables when
CONFIG_DEBUG_SG is enabled.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: linuxppc-dev@lists.ozlabs.org
Cc: linux-arch@vger.kernel.org
---
* New patch from v2

 arch/powerpc/kernel/vio.c | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/arch/powerpc/kernel/vio.c b/arch/powerpc/kernel/vio.c
index 5bfdab9..b7a6844 100644
--- a/arch/powerpc/kernel/vio.c
+++ b/arch/powerpc/kernel/vio.c
@@ -557,11 +557,11 @@ static int vio_dma_iommu_map_sg(struct device *dev, struct scatterlist *sglist,
 	struct vio_dev *viodev = to_vio_dev(dev);
 	struct iommu_table *tbl;
 	struct scatterlist *sgl;
-	int ret, count = 0;
+	int ret, count;
 	size_t alloc_size = 0;
 
 	tbl = get_iommu_table_base(dev);
-	for (sgl = sglist; count < nelems; count++, sgl++)
+	for_each_sg(sglist, sgl, nelems, count)
 		alloc_size += roundup(sgl->length, IOMMU_PAGE_SIZE(tbl));
 
 	if (vio_cmo_alloc(viodev, alloc_size)) {
@@ -577,7 +577,7 @@ static int vio_dma_iommu_map_sg(struct device *dev, struct scatterlist *sglist,
 		return ret;
 	}
 
-	for (sgl = sglist, count = 0; count < ret; count++, sgl++)
+	for_each_sg(sglist, sgl, ret, count)
 		alloc_size -= roundup(sgl->dma_length, IOMMU_PAGE_SIZE(tbl));
 	if (alloc_size)
 		vio_cmo_dealloc(viodev, alloc_size);
@@ -594,10 +594,10 @@ static void vio_dma_iommu_unmap_sg(struct device *dev,
 	struct iommu_table *tbl;
 	struct scatterlist *sgl;
 	size_t alloc_size = 0;
-	int count = 0;
+	int count;
 
 	tbl = get_iommu_table_base(dev);
-	for (sgl = sglist; count < nelems; count++, sgl++)
+	for_each_sg(sglist, sgl, nelems, count)
 		alloc_size += roundup(sgl->dma_length, IOMMU_PAGE_SIZE(tbl));
 
 	dma_iommu_ops.unmap_sg(dev, sglist, nelems, direction, attrs);
-- 
1.9.1

[PATCH v2 09/10] sparc: use for_each_sg()

[Akinobu Mita]

This replaces the plain loop over the sglist array with for_each_sg()
macro which consists of sg_next() function calls.  Since sparc does
select ARCH_HAS_SG_CHAIN, it is necessary to use for_each_sg() in
order to loop over each sg element.  This also help find problems with
drivers that do not properly initialize their sg tables when
CONFIG_DEBUG_SG is enabled.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: sparclinux@vger.kernel.org
Cc: linux-arch@vger.kernel.org
---
* New patch from v2

 arch/sparc/kernel/ldc.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/arch/sparc/kernel/ldc.c b/arch/sparc/kernel/ldc.c
index 7d3ca30..1ae5eb1 100644
--- a/arch/sparc/kernel/ldc.c
+++ b/arch/sparc/kernel/ldc.c
@@ -2086,6 +2086,7 @@ int ldc_map_sg(struct ldc_channel *lp,
 	struct cookie_state state;
 	struct ldc_iommu *iommu;
 	int err;
+	struct scatterlist *s;
 
 	if (map_perm & ~LDC_MAP_ALL)
 		return -EINVAL;
@@ -2112,9 +2113,10 @@ int ldc_map_sg(struct ldc_channel *lp,
 	state.pte_idx = (base - iommu->page_table);
 	state.nc = 0;
 
-	for (i = 0; i < num_sg; i++)
-		fill_cookies(&state, page_to_pfn(sg_page(&sg[i])) << PAGE_SHIFT,
-			     sg[i].offset, sg[i].length);
+	for_each_sg(sg, s, num_sg, i) {
+		fill_cookies(&state, page_to_pfn(sg_page(s)) << PAGE_SHIFT,
+			     s->offset, s->length);
+	}
 
 	return state.nc;
 }
-- 
1.9.1

[PATCH v2 10/10] parisc: use for_each_sg()

[Akinobu Mita]

This replaces the plain loop over the sglist array with for_each_sg()
macro which consists of sg_next() function calls.  Since parisc doesn't
select ARCH_HAS_SG_CHAIN, it is not necessary to use for_each_sg() in
order to loop over each sg element.  But this can help find problems
with drivers that do not properly initialize their sg tables when
CONFIG_DEBUG_SG is enabled.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: Helge Deller <deller@gmx.de>
Cc: linux-parisc@vger.kernel.org
Cc: linux-arch@vger.kernel.org
---
* New patch from v2

 arch/parisc/kernel/pci-dma.c | 27 ++++++++++++++++-----------
 1 file changed, 16 insertions(+), 11 deletions(-)

diff --git a/arch/parisc/kernel/pci-dma.c b/arch/parisc/kernel/pci-dma.c
index ff834fd..b9402c9 100644
--- a/arch/parisc/kernel/pci-dma.c
+++ b/arch/parisc/kernel/pci-dma.c
@@ -478,14 +478,16 @@ static void pa11_dma_unmap_single(struct device *dev, dma_addr_t dma_handle, siz
 static int pa11_dma_map_sg(struct device *dev, struct scatterlist *sglist, int nents, enum dma_data_direction direction)
 {
 	int i;
+	struct scatterlist *sg;
 
 	BUG_ON(direction == DMA_NONE);
 
-	for (i = 0; i < nents; i++, sglist++ ) {
-		unsigned long vaddr = (unsigned long)sg_virt(sglist);
-		sg_dma_address(sglist) = (dma_addr_t) virt_to_phys(vaddr);
-		sg_dma_len(sglist) = sglist->length;
-		flush_kernel_dcache_range(vaddr, sglist->length);
+	for_each_sg(sglist, sg, nents, i) {
+		unsigned long vaddr = (unsigned long)sg_virt(sg);
+
+		sg_dma_address(sg) = (dma_addr_t) virt_to_phys(vaddr);
+		sg_dma_len(sg) = sg->length;
+		flush_kernel_dcache_range(vaddr, sg->length);
 	}
 	return nents;
 }
@@ -493,6 +495,7 @@ static int pa11_dma_map_sg(struct device *dev, struct scatterlist *sglist, int n
 static void pa11_dma_unmap_sg(struct device *dev, struct scatterlist *sglist, int nents, enum dma_data_direction direction)
 {
 	int i;
+	struct scatterlist *sg;
 
 	BUG_ON(direction == DMA_NONE);
 
@@ -501,8 +504,8 @@ static void pa11_dma_unmap_sg(struct device *dev, struct scatterlist *sglist, in
 
 	/* once we do combining we'll need to use phys_to_virt(sg_dma_address(sglist)) */
 
-	for (i = 0; i < nents; i++, sglist++ )
-		flush_kernel_vmap_range(sg_virt(sglist), sglist->length);
+	for_each_sg(sglist, sg, nents, i)
+		flush_kernel_vmap_range(sg_virt(sg), sg->length);
 	return;
 }
 
@@ -523,21 +526,23 @@ static void pa11_dma_sync_single_for_device(struct device *dev, dma_addr_t dma_h
 static void pa11_dma_sync_sg_for_cpu(struct device *dev, struct scatterlist *sglist, int nents, enum dma_data_direction direction)
 {
 	int i;
+	struct scatterlist *sg;
 
 	/* once we do combining we'll need to use phys_to_virt(sg_dma_address(sglist)) */
 
-	for (i = 0; i < nents; i++, sglist++ )
-		flush_kernel_vmap_range(sg_virt(sglist), sglist->length);
+	for_each_sg(sglist, sg, nents, i)
+		flush_kernel_vmap_range(sg_virt(sg), sg->length);
 }
 
 static void pa11_dma_sync_sg_for_device(struct device *dev, struct scatterlist *sglist, int nents, enum dma_data_direction direction)
 {
 	int i;
+	struct scatterlist *sg;
 
 	/* once we do combining we'll need to use phys_to_virt(sg_dma_address(sglist)) */
 
-	for (i = 0; i < nents; i++, sglist++ )
-		flush_kernel_vmap_range(sg_virt(sglist), sglist->length);
+	for_each_sg(sglist, sg, nents, i)
+		flush_kernel_vmap_range(sg_virt(sg), sg->length);
 }
 
 struct hppa_dma_ops pcxl_dma_ops = {
-- 
1.9.1

Re: [PATCH v2 01/10] m68k: use for_each_sg()

[Geert Uytterhoeven]

On Fri, May 1, 2015 at 3:56 PM, Akinobu Mita <akinobu.mita@gmail.com> wrote:
> This replaces the plain loop over the sglist array with for_each_sg()
> macro which consists of sg_next() function calls.  Since m68k doesn't
> select ARCH_HAS_SG_CHAIN, it is not necessary to use for_each_sg() in
> order to loop over each sg element.  But this can help find problems
> with drivers that do not properly initialize their sg tables when
> CONFIG_DEBUG_SG is enabled.
>
> Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
> Cc: Geert Uytterhoeven <geert@linux-m68k.org>
> Cc: linux-m68k@lists.linux-m68k.org
> Cc: linux-arch@vger.kernel.org
> ---
> * Changes from v1
> - Update commit log

Thanks, applied, and queued for v4.2.

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds