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/parisc/kernel/pci-dma.c

@@ -414,7 +414,7 @@ pcxl_dma_init(void)
 __initcall(pcxl_dma_init);
 
 static void *pa11_dma_alloc(struct device *dev, size_t size,
-		dma_addr_t *dma_handle, gfp_t flag, struct dma_attrs *attrs)
+		dma_addr_t *dma_handle, gfp_t flag, unsigned long attrs)
 {
 	unsigned long vaddr;
 	unsigned long paddr;
@@ -441,7 +441,7 @@ static void *pa11_dma_alloc(struct device *dev, size_t size,
 }
 
 static void pa11_dma_free(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)
 {
 	int order;
 
@@ -454,7 +454,7 @@ static void pa11_dma_free(struct device *dev, size_t size, void *vaddr,
 
 static dma_addr_t pa11_dma_map_page(struct device *dev, struct page *page,
 		unsigned long offset, size_t size,
-		enum dma_data_direction direction, struct dma_attrs *attrs)
+		enum dma_data_direction direction, unsigned long attrs)
 {
 	void *addr = page_address(page) + offset;
 	BUG_ON(direction == DMA_NONE);
@@ -465,7 +465,7 @@ static dma_addr_t pa11_dma_map_page(struct device *dev, struct page *page,
 
 static void pa11_dma_unmap_page(struct device *dev, dma_addr_t dma_handle,
 		size_t size, enum dma_data_direction direction,
-		struct dma_attrs *attrs)
+		unsigned long attrs)
 {
 	BUG_ON(direction == DMA_NONE);
 
@@ -484,7 +484,7 @@ static void pa11_dma_unmap_page(struct device *dev, dma_addr_t dma_handle,
 
 static int pa11_dma_map_sg(struct device *dev, struct scatterlist *sglist,
 		int nents, enum dma_data_direction direction,
-		struct dma_attrs *attrs)
+		unsigned long attrs)
 {
 	int i;
 	struct scatterlist *sg;
@@ -503,7 +503,7 @@ static int pa11_dma_map_sg(struct device *dev, struct scatterlist *sglist,
 
 static void pa11_dma_unmap_sg(struct device *dev, struct scatterlist *sglist,
 		int nents, enum dma_data_direction direction,
-		struct dma_attrs *attrs)
+		unsigned long attrs)
 {
 	int i;
 	struct scatterlist *sg;
@@ -577,11 +577,11 @@ struct dma_map_ops pcxl_dma_ops = {
 };
 
 static void *pcx_dma_alloc(struct device *dev, size_t size,
-		dma_addr_t *dma_handle, gfp_t flag, struct dma_attrs *attrs)
+		dma_addr_t *dma_handle, gfp_t flag, unsigned long attrs)
 {
 	void *addr;
 
-	if (!dma_get_attr(DMA_ATTR_NON_CONSISTENT, attrs))
+	if ((attrs & DMA_ATTR_NON_CONSISTENT) == 0)
 		return NULL;
 
 	addr = (void *)__get_free_pages(flag, get_order(size));
@@ -592,7 +592,7 @@ static void *pcx_dma_alloc(struct device *dev, size_t size,
 }
 
 static void pcx_dma_free(struct device *dev, size_t size, void *vaddr,
-		dma_addr_t iova, struct dma_attrs *attrs)
+		dma_addr_t iova, unsigned long attrs)
 {
 	free_pages((unsigned long)vaddr, get_order(size));
 	return;