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/1468399300-5399-2-git-send-email-k.kozlowski@samsung.com
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Acked-by: Vineet Gupta <vgupta@synopsys.com>
Acked-by: Robin Murphy <robin.murphy@arm.com>
Acked-by: Hans-Christian Noren Egtvedt <egtvedt@samfundet.no>
Acked-by: Mark Salter <msalter@redhat.com> [c6x]
Acked-by: Jesper Nilsson <jesper.nilsson@axis.com> [cris]
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch> [drm]
Reviewed-by: Bart Van Assche <bart.vanassche@sandisk.com>
Acked-by: Joerg Roedel <jroedel@suse.de> [iommu]
Acked-by: Fabien Dessenne <fabien.dessenne@st.com> [bdisp]
Reviewed-by: Marek Szyprowski <m.szyprowski@samsung.com> [vb2-core]
Acked-by: David Vrabel <david.vrabel@citrix.com> [xen]
Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> [xen swiotlb]
Acked-by: Joerg Roedel <jroedel@suse.de> [iommu]
Acked-by: Richard Kuo <rkuo@codeaurora.org> [hexagon]
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> [m68k]
Acked-by: Gerald Schaefer <gerald.schaefer@de.ibm.com> [s390]
Acked-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Acked-by: Hans-Christian Noren Egtvedt <egtvedt@samfundet.no> [avr32]
Acked-by: Vineet Gupta <vgupta@synopsys.com> [arc]
Acked-by: Robin Murphy <robin.murphy@arm.com> [arm64 and dma-iommu]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

4 files changed, 8 insertions, 8 deletions

diff --git a/arch/powerpc/platforms/powernv/npu-dma.c b/arch/powerpc/platforms/powernv/npu-dma.c
index 4383a5ff82ba..00e1a0195c78 100644
--- a/arch/powerpc/platforms/powernv/npu-dma.c
+++ b/arch/powerpc/platforms/powernv/npu-dma.c
@@ -73,7 +73,7 @@ EXPORT_SYMBOL(pnv_pci_get_npu_dev);
 
 static void *dma_npu_alloc(struct device *dev, size_t size,
 			   dma_addr_t *dma_handle, gfp_t flag,
-			   struct dma_attrs *attrs)
+			   unsigned long attrs)
 {
 	NPU_DMA_OP_UNSUPPORTED();
 	return NULL;
@@ -81,7 +81,7 @@ static void *dma_npu_alloc(struct device *dev, size_t size,
 
 static void dma_npu_free(struct device *dev, size_t size,
 			 void *vaddr, dma_addr_t dma_handle,
-			 struct dma_attrs *attrs)
+			 unsigned long attrs)
 {
 	NPU_DMA_OP_UNSUPPORTED();
 }
@@ -89,7 +89,7 @@ static void dma_npu_free(struct device *dev, size_t size,
 static dma_addr_t dma_npu_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)
 {
 	NPU_DMA_OP_UNSUPPORTED();
 	return 0;
@@ -97,7 +97,7 @@ static dma_addr_t dma_npu_map_page(struct device *dev, struct page *page,
 
 static int dma_npu_map_sg(struct device *dev, struct scatterlist *sglist,
 			  int nelems, enum dma_data_direction direction,
-			  struct dma_attrs *attrs)
+			  unsigned long attrs)
 {
 	NPU_DMA_OP_UNSUPPORTED();
 	return 0;
diff --git a/arch/powerpc/platforms/powernv/pci-ioda.c b/arch/powerpc/platforms/powernv/pci-ioda.c
index 891fc4a453df..6b9528307f62 100644
--- a/arch/powerpc/platforms/powernv/pci-ioda.c
+++ b/arch/powerpc/platforms/powernv/pci-ioda.c
@@ -1806,7 +1806,7 @@ static void pnv_pci_p7ioc_tce_invalidate(struct iommu_table *tbl,
 static int pnv_ioda1_tce_build(struct iommu_table *tbl, long index,
 		long npages, unsigned long uaddr,
 		enum dma_data_direction direction,
-		struct dma_attrs *attrs)
+		unsigned long attrs)
 {
 	int ret = pnv_tce_build(tbl, index, npages, uaddr, direction,
 			attrs);
@@ -1950,7 +1950,7 @@ static void pnv_pci_ioda2_tce_invalidate(struct iommu_table *tbl,
 static int pnv_ioda2_tce_build(struct iommu_table *tbl, long index,
 		long npages, unsigned long uaddr,
 		enum dma_data_direction direction,
-		struct dma_attrs *attrs)
+		unsigned long attrs)
 {
 	int ret = pnv_tce_build(tbl, index, npages, uaddr, direction,
 			attrs);
diff --git a/arch/powerpc/platforms/powernv/pci.c b/arch/powerpc/platforms/powernv/pci.c
index 6701dd5ded20..a21d831c1114 100644
--- a/arch/powerpc/platforms/powernv/pci.c
+++ b/arch/powerpc/platforms/powernv/pci.c
@@ -704,7 +704,7 @@ static __be64 *pnv_tce(struct iommu_table *tbl, long idx)
 
 int pnv_tce_build(struct iommu_table *tbl, long index, long npages,
 		unsigned long uaddr, enum dma_data_direction direction,
-		struct dma_attrs *attrs)
+		unsigned long attrs)
 {
 	u64 proto_tce = iommu_direction_to_tce_perm(direction);
 	u64 rpn = __pa(uaddr) >> tbl->it_page_shift;
diff --git a/arch/powerpc/platforms/powernv/pci.h b/arch/powerpc/platforms/powernv/pci.h
index d088d4f06116..e64df7894d6e 100644
--- a/arch/powerpc/platforms/powernv/pci.h
+++ b/arch/powerpc/platforms/powernv/pci.h
@@ -181,7 +181,7 @@ struct pnv_phb {
 extern struct pci_ops pnv_pci_ops;
 extern int pnv_tce_build(struct iommu_table *tbl, long index, long npages,
 		unsigned long uaddr, enum dma_data_direction direction,
-		struct dma_attrs *attrs);
+		unsigned long attrs);
 extern void pnv_tce_free(struct iommu_table *tbl, long index, long npages);
 extern int pnv_tce_xchg(struct iommu_table *tbl, long index,
 		unsigned long *hpa, enum dma_data_direction *direction);