dma-mapping: use unsigned long for dma_attrs

The dma-mapping core and the implementations do not change the DMA
attributes passed by pointer.  Thus the pointer can point to const data.
However the attributes do not have to be a bitfield.  Instead unsigned
long will do fine:

1. This is just simpler.  Both in terms of reading the code and setting
   attributes.  Instead of initializing local attributes on the stack
   and passing pointer to it to dma_set_attr(), just set the bits.

2. It brings safeness and checking for const correctness because the
   attributes are passed by value.

Semantic patches for this change (at least most of them):

    virtual patch
    virtual context

    @r@
    identifier f, attrs;

    @@
    f(...,
    - struct dma_attrs *attrs
    + unsigned long attrs
    , ...)
    {
    ...
    }

    @@
    identifier r.f;
    @@
    f(...,
    - NULL
    + 0
     )

and

    // Options: --all-includes
    virtual patch
    virtual context

    @r@
    identifier f, attrs;
    type t;

    @@
    t f(..., struct dma_attrs *attrs);

    @@
    identifier r.f;
    @@
    f(...,
    - NULL
    + 0
     )

Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Krzysztof Kozlowski <[email protected]>
Acked-by: Vineet Gupta <[email protected]>
Acked-by: Robin Murphy <[email protected]>
Acked-by: Hans-Christian Noren Egtvedt <[email protected]>
Acked-by: Mark Salter <[email protected]> [c6x]
Acked-by: Jesper Nilsson <[email protected]> [cris]
Acked-by: Daniel Vetter <[email protected]> [drm]
Reviewed-by: Bart Van Assche <[email protected]>
Acked-by: Joerg Roedel <[email protected]> [iommu]
Acked-by: Fabien Dessenne <[email protected]> [bdisp]
Reviewed-by: Marek Szyprowski <[email protected]> [vb2-core]
Acked-by: David Vrabel <[email protected]> [xen]
Acked-by: Konrad Rzeszutek Wilk <[email protected]> [xen swiotlb]
Acked-by: Joerg Roedel <[email protected]> [iommu]
Acked-by: Richard Kuo <[email protected]> [hexagon]
Acked-by: Geert Uytterhoeven <[email protected]> [m68k]
Acked-by: Gerald Schaefer <[email protected]> [s390]
Acked-by: Bjorn Andersson <[email protected]>
Acked-by: Hans-Christian Noren Egtvedt <[email protected]> [avr32]
Acked-by: Vineet Gupta <[email protected]> [arc]
Acked-by: Robin Murphy <[email protected]> [arm64 and dma-iommu]
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

arch/mips/cavium-octeon/dma-octeon.c

@@ -125,7 +125,7 @@ static phys_addr_t octeon_small_dma_to_phys(struct device *dev,
 
 static dma_addr_t octeon_dma_map_page(struct device *dev, struct page *page,
 	unsigned long offset, size_t size, enum dma_data_direction direction,
-	struct dma_attrs *attrs)
+	unsigned long attrs)
 {
 	dma_addr_t daddr = swiotlb_map_page(dev, page, offset, size,
 					    direction, attrs);
@@ -135,7 +135,7 @@ static dma_addr_t octeon_dma_map_page(struct device *dev, struct page *page,
 }
 
 static int octeon_dma_map_sg(struct device *dev, struct scatterlist *sg,
-	int nents, enum dma_data_direction direction, struct dma_attrs *attrs)
+	int nents, enum dma_data_direction direction, unsigned long attrs)
 {
 	int r = swiotlb_map_sg_attrs(dev, sg, nents, direction, attrs);
 	mb();
@@ -157,7 +157,7 @@ static void octeon_dma_sync_sg_for_device(struct device *dev,
 }
 
 static void *octeon_dma_alloc_coherent(struct device *dev, size_t size,
-	dma_addr_t *dma_handle, gfp_t gfp, struct dma_attrs *attrs)
+	dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs)
 {
 	void *ret;
 
@@ -189,7 +189,7 @@ static void *octeon_dma_alloc_coherent(struct device *dev, size_t size,
 }
 
 static void octeon_dma_free_coherent(struct device *dev, size_t size,
-	void *vaddr, dma_addr_t dma_handle, struct dma_attrs *attrs)
+	void *vaddr, dma_addr_t dma_handle, unsigned long attrs)
 {
 	swiotlb_free_coherent(dev, size, vaddr, dma_handle);
 }

arch/mips/loongson64/common/dma-swiotlb.c

@@ -10,7 +10,7 @@
 #include <dma-coherence.h>
 
 static void *loongson_dma_alloc_coherent(struct device *dev, size_t size,
-		dma_addr_t *dma_handle, gfp_t gfp, struct dma_attrs *attrs)
+		dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs)
 {
 	void *ret;
 
@@ -41,7 +41,7 @@ static void *loongson_dma_alloc_coherent(struct device *dev, size_t size,
 }
 
 static void loongson_dma_free_coherent(struct device *dev, size_t size,
-		void *vaddr, dma_addr_t dma_handle, struct dma_attrs *attrs)
+		void *vaddr, dma_addr_t dma_handle, unsigned long attrs)
 {
 	swiotlb_free_coherent(dev, size, vaddr, dma_handle);
 }
@@ -49,7 +49,7 @@ static void loongson_dma_free_coherent(struct device *dev, size_t size,
 static dma_addr_t loongson_dma_map_page(struct device *dev, struct page *page,
 				unsigned long offset, size_t size,
 				enum dma_data_direction dir,
-				struct dma_attrs *attrs)
+				unsigned long attrs)
 {
 	dma_addr_t daddr = swiotlb_map_page(dev, page, offset, size,
 					dir, attrs);
@@ -59,9 +59,9 @@ static dma_addr_t loongson_dma_map_page(struct device *dev, struct page *page,
 
 static int loongson_dma_map_sg(struct device *dev, struct scatterlist *sg,
 				int nents, enum dma_data_direction dir,
-				struct dma_attrs *attrs)
+				unsigned long attrs)
 {
-	int r = swiotlb_map_sg_attrs(dev, sg, nents, dir, NULL);
+	int r = swiotlb_map_sg_attrs(dev, sg, nents, dir, 0);
 	mb();
 
 	return r;

arch/mips/mm/dma-default.c

@@ -131,7 +131,7 @@ static void *mips_dma_alloc_noncoherent(struct device *dev, size_t size,
 }
 
 static void *mips_dma_alloc_coherent(struct device *dev, size_t size,
-	dma_addr_t * dma_handle, gfp_t gfp, struct dma_attrs *attrs)
+	dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs)
 {
 	void *ret;
 	struct page *page = NULL;
@@ -141,7 +141,7 @@ static void *mips_dma_alloc_coherent(struct device *dev, size_t size,
 	 * XXX: seems like the coherent and non-coherent implementations could
 	 * be consolidated.
 	 */
-	if (dma_get_attr(DMA_ATTR_NON_CONSISTENT, attrs))
+	if (attrs & DMA_ATTR_NON_CONSISTENT)
 		return mips_dma_alloc_noncoherent(dev, size, dma_handle, gfp);
 
 	gfp = massage_gfp_flags(dev, gfp);
@@ -176,13 +176,13 @@ static void mips_dma_free_noncoherent(struct device *dev, size_t size,
 }
 
 static void mips_dma_free_coherent(struct device *dev, size_t size, void *vaddr,
-	dma_addr_t dma_handle, struct dma_attrs *attrs)
+	dma_addr_t dma_handle, unsigned long attrs)
 {
 	unsigned long addr = (unsigned long) vaddr;
 	unsigned int count = PAGE_ALIGN(size) >> PAGE_SHIFT;
 	struct page *page = NULL;
 
-	if (dma_get_attr(DMA_ATTR_NON_CONSISTENT, attrs)) {
+	if (attrs & DMA_ATTR_NON_CONSISTENT) {
 		mips_dma_free_noncoherent(dev, size, vaddr, dma_handle);
 		return;
 	}
@@ -200,7 +200,7 @@ static void mips_dma_free_coherent(struct device *dev, size_t size, void *vaddr,
 
 static int mips_dma_mmap(struct device *dev, struct vm_area_struct *vma,
 	void *cpu_addr, dma_addr_t dma_addr, size_t size,
-	struct dma_attrs *attrs)
+	unsigned long attrs)
 {
 	unsigned long user_count = (vma->vm_end - vma->vm_start) >> PAGE_SHIFT;
 	unsigned long count = PAGE_ALIGN(size) >> PAGE_SHIFT;
@@ -214,7 +214,7 @@ static int mips_dma_mmap(struct device *dev, struct vm_area_struct *vma,
 
 	pfn = page_to_pfn(virt_to_page((void *)addr));
 
-	if (dma_get_attr(DMA_ATTR_WRITE_COMBINE, attrs))
+	if (attrs & DMA_ATTR_WRITE_COMBINE)
 		vma->vm_page_prot = pgprot_writecombine(vma->vm_page_prot);
 	else
 		vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
@@ -291,7 +291,7 @@ static inline void __dma_sync(struct page *page,
 }
 
 static void mips_dma_unmap_page(struct device *dev, dma_addr_t dma_addr,
-	size_t size, enum dma_data_direction direction, struct dma_attrs *attrs)
+	size_t size, enum dma_data_direction direction, unsigned long attrs)
 {
 	if (cpu_needs_post_dma_flush(dev))
 		__dma_sync(dma_addr_to_page(dev, dma_addr),
@@ -301,7 +301,7 @@ static void mips_dma_unmap_page(struct device *dev, dma_addr_t dma_addr,
 }
 
 static int mips_dma_map_sg(struct device *dev, struct scatterlist *sglist,
-	int nents, enum dma_data_direction direction, struct dma_attrs *attrs)
+	int nents, enum dma_data_direction direction, unsigned long attrs)
 {
 	int i;
 	struct scatterlist *sg;
@@ -322,7 +322,7 @@ static int mips_dma_map_sg(struct device *dev, struct scatterlist *sglist,
 
 static dma_addr_t mips_dma_map_page(struct device *dev, struct page *page,
 	unsigned long offset, size_t size, enum dma_data_direction direction,
-	struct dma_attrs *attrs)
+	unsigned long attrs)
 {
 	if (!plat_device_is_coherent(dev))
 		__dma_sync(page, offset, size, direction);
@@ -332,7 +332,7 @@ static dma_addr_t mips_dma_map_page(struct device *dev, struct page *page,
 
 static void mips_dma_unmap_sg(struct device *dev, struct scatterlist *sglist,
 	int nhwentries, enum dma_data_direction direction,
-	struct dma_attrs *attrs)
+	unsigned long attrs)
 {
 	int i;
 	struct scatterlist *sg;

arch/mips/netlogic/common/nlm-dma.c

@@ -45,7 +45,7 @@
 static char *nlm_swiotlb;
 
 static void *nlm_dma_alloc_coherent(struct device *dev, size_t size,
-	dma_addr_t *dma_handle, gfp_t gfp, struct dma_attrs *attrs)
+	dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs)
 {
 	/* ignore region specifiers */
 	gfp &= ~(__GFP_DMA | __GFP_DMA32 | __GFP_HIGHMEM);
@@ -62,7 +62,7 @@ static void *nlm_dma_alloc_coherent(struct device *dev, size_t size,
 }
 
 static void nlm_dma_free_coherent(struct device *dev, size_t size,
-	void *vaddr, dma_addr_t dma_handle, struct dma_attrs *attrs)
+	void *vaddr, dma_addr_t dma_handle, unsigned long attrs)
 {
 	swiotlb_free_coherent(dev, size, vaddr, dma_handle);
 }