[PATCH v6 00/46] dma-mapping: Use unsigned long for dma_attrs

[PATCH v6 00/46] dma-mapping: Use unsigned long for dma_attrs

[Krzysztof Kozlowski]

Hi,

The fifth version of this patchset was merged by Andrew Morton
few days ago.  It was rebased on v4.7-rc5 so it missed some ongoing
changes.

This is just rebase on next-20160713.


For easier testing the patchset is available here:
repo:   https://github.com/krzk/linux
branch: for-next/dma-attrs-const-v6


Changes since v5
================
1. New patches:
   1/46:  [media] mtk-vcodec: Remove unused dma_attrs
   44/46: remoteproc: qcom: Use unsigned long for dma_attrs
2. 19/46: rebased on next, some more changes inside
3. Added accumulated acks: Marek Szyprowski, Richard Kuo,
   Konrad Rzeszutek Wilk, Daniel Vetter and Joerg Roedel.


Changes since v4
================
1. Collect some acks. Still need more.
2. Minor fixes pointed by Robin Murphy.
3. Applied changes from Bart Van Assche's comment.
4. More tests and builds (using https://www.kernel.org/pub/tools/crosstool/).


Changes since v3
================
1. Collect some acks.
2. Drop wrong patch 1/45 ("powerpc: dma-mapping: Don't hard-code
   the value of DMA_ATTR_WEAK_ORDERING").
3. Minor fix pointed out by Michael Ellerman.


Changes since v2
================
1. Follow Christoph Hellwig's comments (don't use BIT add
   documentation, remove dma_get_attr).


Rationale
=========
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.


Best regards,
Krzysztof


Krzysztof Kozlowski (46):
  [media] mtk-vcodec: Remove unused dma_attrs
  dma-mapping: Use unsigned long for dma_attrs
  alpha: dma-mapping: Use unsigned long for dma_attrs
  arc: dma-mapping: Use unsigned long for dma_attrs
  ARM: dma-mapping: Use unsigned long for dma_attrs
  arm64: dma-mapping: Use unsigned long for dma_attrs
  avr32: dma-mapping: Use unsigned long for dma_attrs
  blackfin: dma-mapping: Use unsigned long for dma_attrs
  c6x: dma-mapping: Use unsigned long for dma_attrs
  cris: dma-mapping: Use unsigned long for dma_attrs
  frv: dma-mapping: Use unsigned long for dma_attrs
  drm/exynos: dma-mapping: Use unsigned long for dma_attrs
  drm/mediatek: dma-mapping: Use unsigned long for dma_attrs
  drm/msm: dma-mapping: Use unsigned long for dma_attrs
  drm/nouveau: dma-mapping: Use unsigned long for dma_attrs
  drm/rockship: dma-mapping: Use unsigned long for dma_attrs
  infiniband: dma-mapping: Use unsigned long for dma_attrs
  iommu: dma-mapping: Use unsigned long for dma_attrs
  [media] dma-mapping: Use unsigned long for dma_attrs
  xen: dma-mapping: Use unsigned long for dma_attrs
  swiotlb: dma-mapping: Use unsigned long for dma_attrs
  powerpc: dma-mapping: Use unsigned long for dma_attrs
  video: dma-mapping: Use unsigned long for dma_attrs
  x86: dma-mapping: Use unsigned long for dma_attrs
  iommu: intel: dma-mapping: Use unsigned long for dma_attrs
  h8300: dma-mapping: Use unsigned long for dma_attrs
  hexagon: dma-mapping: Use unsigned long for dma_attrs
  ia64: dma-mapping: Use unsigned long for dma_attrs
  m68k: dma-mapping: Use unsigned long for dma_attrs
  metag: dma-mapping: Use unsigned long for dma_attrs
  microblaze: dma-mapping: Use unsigned long for dma_attrs
  mips: dma-mapping: Use unsigned long for dma_attrs
  mn10300: dma-mapping: Use unsigned long for dma_attrs
  nios2: dma-mapping: Use unsigned long for dma_attrs
  openrisc: dma-mapping: Use unsigned long for dma_attrs
  parisc: dma-mapping: Use unsigned long for dma_attrs
  misc: mic: dma-mapping: Use unsigned long for dma_attrs
  s390: dma-mapping: Use unsigned long for dma_attrs
  sh: dma-mapping: Use unsigned long for dma_attrs
  sparc: dma-mapping: Use unsigned long for dma_attrs
  tile: dma-mapping: Use unsigned long for dma_attrs
  unicore32: dma-mapping: Use unsigned long for dma_attrs
  xtensa: dma-mapping: Use unsigned long for dma_attrs
  remoteproc: qcom: Use unsigned long for dma_attrs
  dma-mapping: Remove dma_get_attr
  dma-mapping: Document the DMA attributes next to the declaration

 Documentation/DMA-API.txt                          |  33 +++---
 Documentation/DMA-attributes.txt                   |   2 +-
 arch/alpha/include/asm/dma-mapping.h               |   2 -
 arch/alpha/kernel/pci-noop.c                       |   2 +-
 arch/alpha/kernel/pci_iommu.c                      |  12 +-
 arch/arc/mm/dma.c                                  |  12 +-
 arch/arm/common/dmabounce.c                        |   4 +-
 arch/arm/include/asm/dma-mapping.h                 |  13 +--
 arch/arm/include/asm/xen/page-coherent.h           |  16 +--
 arch/arm/mm/dma-mapping.c                          | 117 +++++++++----------
 arch/arm/xen/mm.c                                  |   8 +-
 arch/arm64/mm/dma-mapping.c                        |  66 +++++------
 arch/avr32/mm/dma-coherent.c                       |  12 +-
 arch/blackfin/kernel/dma-mapping.c                 |   8 +-
 arch/c6x/include/asm/dma-mapping.h                 |   4 +-
 arch/c6x/kernel/dma.c                              |   9 +-
 arch/c6x/mm/dma-coherent.c                         |   4 +-
 arch/cris/arch-v32/drivers/pci/dma.c               |   9 +-
 arch/frv/mb93090-mb00/pci-dma-nommu.c              |   8 +-
 arch/frv/mb93090-mb00/pci-dma.c                    |   9 +-
 arch/h8300/kernel/dma.c                            |   8 +-
 arch/hexagon/include/asm/dma-mapping.h             |   1 -
 arch/hexagon/kernel/dma.c                          |   8 +-
 arch/ia64/hp/common/sba_iommu.c                    |  22 ++--
 arch/ia64/include/asm/machvec.h                    |   1 -
 arch/ia64/kernel/pci-swiotlb.c                     |   4 +-
 arch/ia64/sn/pci/pci_dma.c                         |  22 ++--
 arch/m68k/kernel/dma.c                             |  12 +-
 arch/metag/kernel/dma.c                            |  16 +--
 arch/microblaze/include/asm/dma-mapping.h          |   1 -
 arch/microblaze/kernel/dma.c                       |  12 +-
 arch/mips/cavium-octeon/dma-octeon.c               |   8 +-
 arch/mips/loongson64/common/dma-swiotlb.c          |  10 +-
 arch/mips/mm/dma-default.c                         |  20 ++--
 arch/mips/netlogic/common/nlm-dma.c                |   4 +-
 arch/mn10300/mm/dma-alloc.c                        |   8 +-
 arch/nios2/mm/dma-mapping.c                        |  12 +-
 arch/openrisc/kernel/dma.c                         |  21 ++--
 arch/parisc/kernel/pci-dma.c                       |  18 +--
 arch/powerpc/include/asm/dma-mapping.h             |   7 +-
 arch/powerpc/include/asm/iommu.h                   |  10 +-
 arch/powerpc/kernel/dma-iommu.c                    |  12 +-
 arch/powerpc/kernel/dma.c                          |  18 +--
 arch/powerpc/kernel/ibmebus.c                      |  12 +-
 arch/powerpc/kernel/iommu.c                        |  12 +-
 arch/powerpc/kernel/vio.c                          |  12 +-
 arch/powerpc/platforms/cell/iommu.c                |  28 ++---
 arch/powerpc/platforms/pasemi/iommu.c              |   2 +-
 arch/powerpc/platforms/powernv/npu-dma.c           |   8 +-
 arch/powerpc/platforms/powernv/pci-ioda.c          |   4 +-
 arch/powerpc/platforms/powernv/pci.c               |   2 +-
 arch/powerpc/platforms/powernv/pci.h               |   2 +-
 arch/powerpc/platforms/ps3/system-bus.c            |  18 +--
 arch/powerpc/platforms/pseries/iommu.c             |   6 +-
 arch/powerpc/sysdev/dart_iommu.c                   |   2 +-
 arch/s390/include/asm/dma-mapping.h                |   1 -
 arch/s390/pci/pci_dma.c                            |  23 ++--
 arch/sh/include/asm/dma-mapping.h                  |   4 +-
 arch/sh/kernel/dma-nommu.c                         |   4 +-
 arch/sh/mm/consistent.c                            |   4 +-
 arch/sparc/kernel/iommu.c                          |  12 +-
 arch/sparc/kernel/ioport.c                         |  24 ++--
 arch/sparc/kernel/pci_sun4v.c                      |  12 +-
 arch/tile/kernel/pci-dma.c                         |  28 ++---
 arch/unicore32/mm/dma-swiotlb.c                    |   4 +-
 arch/x86/include/asm/dma-mapping.h                 |   5 +-
 arch/x86/include/asm/swiotlb.h                     |   4 +-
 arch/x86/include/asm/xen/page-coherent.h           |   9 +-
 arch/x86/kernel/amd_gart_64.c                      |  20 ++--
 arch/x86/kernel/pci-calgary_64.c                   |  14 +--
 arch/x86/kernel/pci-dma.c                          |   4 +-
 arch/x86/kernel/pci-nommu.c                        |   4 +-
 arch/x86/kernel/pci-swiotlb.c                      |   4 +-
 arch/x86/pci/sta2x11-fixup.c                       |   2 +-
 arch/x86/pci/vmd.c                                 |  16 +--
 arch/xtensa/kernel/pci-dma.c                       |  12 +-
 drivers/gpu/drm/exynos/exynos_drm_fbdev.c          |   2 +-
 drivers/gpu/drm/exynos/exynos_drm_g2d.c            |  12 +-
 drivers/gpu/drm/exynos/exynos_drm_gem.c            |  20 ++--
 drivers/gpu/drm/exynos/exynos_drm_gem.h            |   2 +-
 drivers/gpu/drm/mediatek/mtk_drm_gem.c             |  13 +--
 drivers/gpu/drm/mediatek/mtk_drm_gem.h             |   2 +-
 drivers/gpu/drm/msm/msm_drv.c                      |  13 +--
 .../gpu/drm/nouveau/nvkm/subdev/instmem/gk20a.c    |  13 +--
 drivers/gpu/drm/rockchip/rockchip_drm_gem.c        |  17 ++-
 drivers/gpu/drm/rockchip/rockchip_drm_gem.h        |   2 +-
 drivers/infiniband/core/umem.c                     |   7 +-
 drivers/iommu/amd_iommu.c                          |  12 +-
 drivers/iommu/dma-iommu.c                          |   8 +-
 drivers/iommu/intel-iommu.c                        |  12 +-
 .../media/platform/mtk-vcodec/mtk_vcodec_enc_drv.c |   4 -
 drivers/media/platform/sti/bdisp/bdisp-hw.c        |  26 ++---
 drivers/media/v4l2-core/videobuf2-dma-contig.c     |  28 ++---
 drivers/media/v4l2-core/videobuf2-dma-sg.c         |  21 +---
 drivers/media/v4l2-core/videobuf2-vmalloc.c        |   2 +-
 drivers/misc/mic/host/mic_boot.c                   |  20 ++--
 drivers/parisc/ccio-dma.c                          |  16 +--
 drivers/parisc/sba_iommu.c                         |  16 +--
 drivers/remoteproc/qcom_q6v5_pil.c                 |   7 +-
 drivers/video/fbdev/omap2/omapfb/omapfb-main.c     |  12 +-
 drivers/video/fbdev/omap2/omapfb/omapfb.h          |   3 +-
 drivers/xen/swiotlb-xen.c                          |  14 +--
 include/linux/dma-attrs.h                          |  71 ------------
 include/linux/dma-iommu.h                          |   6 +-
 include/linux/dma-mapping.h                        | 128 ++++++++++++++-------
 include/linux/swiotlb.h                            |  10 +-
 include/media/videobuf2-core.h                     |   6 +-
 include/media/videobuf2-dma-contig.h               |   2 -
 include/rdma/ib_verbs.h                            |   8 +-
 include/xen/swiotlb-xen.h                          |  12 +-
 lib/dma-noop.c                                     |   9 +-
 lib/swiotlb.c                                      |  13 ++-
 112 files changed, 694 insertions(+), 798 deletions(-)
 delete mode 100644 include/linux/dma-attrs.h

-- 
1.9.1

[PATCH v6 04/46] arc: dma-mapping: Use unsigned long for dma_attrs

[Krzysztof Kozlowski]

Split out subsystem specific changes for easier reviews. This will be
squashed with main commit.

Signed-off-by: Krzysztof Kozlowski <k.kozlowski at samsung.com>
[for arc]
Acked-by: Vineet Gupta <vgupta at synopsys.com>
---
 arch/arc/mm/dma.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/arch/arc/mm/dma.c b/arch/arc/mm/dma.c
index 73d7e4c75b7d..3d1f467d1792 100644
--- a/arch/arc/mm/dma.c
+++ b/arch/arc/mm/dma.c
@@ -22,7 +22,7 @@
 
 
 static void *arc_dma_alloc(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)
 {
 	unsigned long order = get_order(size);
 	struct page *page;
@@ -90,7 +90,7 @@ static void *arc_dma_alloc(struct device *dev, size_t size,
 }
 
 static void arc_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)
 {
 	struct page *page = virt_to_page(dma_handle);
 	int is_non_coh = 1;
@@ -129,7 +129,7 @@ static void _dma_cache_sync(phys_addr_t paddr, size_t size,
 
 static dma_addr_t arc_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)
 {
 	phys_addr_t paddr = page_to_phys(page) + offset;
 	_dma_cache_sync(paddr, size, dir);
@@ -137,7 +137,7 @@ static dma_addr_t arc_dma_map_page(struct device *dev, struct page *page,
 }
 
 static int arc_dma_map_sg(struct device *dev, struct scatterlist *sg,
-	   int nents, enum dma_data_direction dir, struct dma_attrs *attrs)
+	   int nents, enum dma_data_direction dir, unsigned long attrs)
 {
 	struct scatterlist *s;
 	int i;
-- 
1.9.1

[PATCH v6 45/46] dma-mapping: Remove dma_get_attr

[Krzysztof Kozlowski]

After switching DMA attributes to unsigned long it is easier to just
compare the bits.

Signed-off-by: Krzysztof Kozlowski <k.kozlowski at samsung.com>
[for avr32]
Acked-by: Hans-Christian Noren Egtvedt <egtvedt at samfundet.no>
[for arc]
Acked-by: Vineet Gupta <vgupta at synopsys.com>
[for arm64 and dma-iommu]
Acked-by: Robin Murphy <robin.murphy at arm.com>
---
 Documentation/DMA-API.txt                      |  4 +--
 arch/arc/mm/dma.c                              |  4 +--
 arch/arm/mm/dma-mapping.c                      | 36 ++++++++++++--------------
 arch/arm/xen/mm.c                              |  4 +--
 arch/arm64/mm/dma-mapping.c                    | 10 +++----
 arch/avr32/mm/dma-coherent.c                   |  4 +--
 arch/ia64/sn/pci/pci_dma.c                     | 10 ++-----
 arch/metag/kernel/dma.c                        |  2 +-
 arch/mips/mm/dma-default.c                     |  6 ++---
 arch/openrisc/kernel/dma.c                     |  4 +--
 arch/parisc/kernel/pci-dma.c                   |  2 +-
 arch/powerpc/platforms/cell/iommu.c            | 12 ++++-----
 drivers/gpu/drm/rockchip/rockchip_drm_gem.c    |  2 +-
 drivers/iommu/dma-iommu.c                      |  2 +-
 drivers/media/v4l2-core/videobuf2-dma-contig.c |  2 +-
 include/linux/dma-mapping.h                    | 10 -------
 16 files changed, 47 insertions(+), 67 deletions(-)

diff --git a/Documentation/DMA-API.txt b/Documentation/DMA-API.txt
index 24f9688bb98a..1d26eeb6b5f6 100644
--- a/Documentation/DMA-API.txt
+++ b/Documentation/DMA-API.txt
@@ -422,9 +422,7 @@ void whizco_dma_map_sg_attrs(struct device *dev, dma_addr_t dma_addr,
 			     unsigned long attrs)
 {
 	....
-	int foo =  dma_get_attr(DMA_ATTR_FOO, attrs);
-	....
-	if (foo)
+	if (attrs & DMA_ATTR_FOO)
 		/* twizzle the frobnozzle */
 	....
 
diff --git a/arch/arc/mm/dma.c b/arch/arc/mm/dma.c
index 3d1f467d1792..74bbe68dce9d 100644
--- a/arch/arc/mm/dma.c
+++ b/arch/arc/mm/dma.c
@@ -46,7 +46,7 @@ static void *arc_dma_alloc(struct device *dev, size_t size,
 	 *   (vs. always going to memory - thus are faster)
 	 */
 	if ((is_isa_arcv2() && ioc_exists) ||
-	    dma_get_attr(DMA_ATTR_NON_CONSISTENT, attrs))
+	    (attrs & DMA_ATTR_NON_CONSISTENT))
 		need_coh = 0;
 
 	/*
@@ -95,7 +95,7 @@ static void arc_dma_free(struct device *dev, size_t size, void *vaddr,
 	struct page *page = virt_to_page(dma_handle);
 	int is_non_coh = 1;
 
-	is_non_coh = dma_get_attr(DMA_ATTR_NON_CONSISTENT, attrs) ||
+	is_non_coh = (attrs & DMA_ATTR_NON_CONSISTENT) ||
 			(is_isa_arcv2() && ioc_exists);
 
 	if (PageHighMem(page) || !is_non_coh)
diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c
index ebb3fde99043..43e03b5293d0 100644
--- a/arch/arm/mm/dma-mapping.c
+++ b/arch/arm/mm/dma-mapping.c
@@ -126,7 +126,7 @@ static dma_addr_t arm_dma_map_page(struct device *dev, struct page *page,
 	     unsigned long offset, size_t size, enum dma_data_direction dir,
 	     unsigned long attrs)
 {
-	if (!dma_get_attr(DMA_ATTR_SKIP_CPU_SYNC, attrs))
+	if ((attrs & DMA_ATTR_SKIP_CPU_SYNC) == 0)
 		__dma_page_cpu_to_dev(page, offset, size, dir);
 	return pfn_to_dma(dev, page_to_pfn(page)) + offset;
 }
@@ -155,7 +155,7 @@ static dma_addr_t arm_coherent_dma_map_page(struct device *dev, struct page *pag
 static void arm_dma_unmap_page(struct device *dev, dma_addr_t handle,
 		size_t size, enum dma_data_direction dir, unsigned long attrs)
 {
-	if (!dma_get_attr(DMA_ATTR_SKIP_CPU_SYNC, attrs))
+	if ((attrs & DMA_ATTR_SKIP_CPU_SYNC) == 0)
 		__dma_page_dev_to_cpu(pfn_to_page(dma_to_pfn(dev, handle)),
 				      handle & ~PAGE_MASK, size, dir);
 }
@@ -622,9 +622,9 @@ static void __free_from_contiguous(struct device *dev, struct page *page,
 
 static inline pgprot_t __get_dma_pgprot(unsigned long attrs, pgprot_t prot)
 {
-	prot = dma_get_attr(DMA_ATTR_WRITE_COMBINE, attrs) ?
-			    pgprot_writecombine(prot) :
-			    pgprot_dmacoherent(prot);
+	prot = (attrs & DMA_ATTR_WRITE_COMBINE) ?
+			pgprot_writecombine(prot) :
+			pgprot_dmacoherent(prot);
 	return prot;
 }
 
@@ -744,7 +744,7 @@ static void *__dma_alloc(struct device *dev, size_t size, dma_addr_t *handle,
 		.gfp = gfp,
 		.prot = prot,
 		.caller = caller,
-		.want_vaddr = !dma_get_attr(DMA_ATTR_NO_KERNEL_MAPPING, attrs),
+		.want_vaddr = ((attrs & DMA_ATTR_NO_KERNEL_MAPPING) == 0),
 	};
 
 #ifdef CONFIG_DMA_API_DEBUG
@@ -887,7 +887,7 @@ static void __arm_dma_free(struct device *dev, size_t size, void *cpu_addr,
 		.size = PAGE_ALIGN(size),
 		.cpu_addr = cpu_addr,
 		.page = page,
-		.want_vaddr = !dma_get_attr(DMA_ATTR_NO_KERNEL_MAPPING, attrs),
+		.want_vaddr = ((attrs & DMA_ATTR_NO_KERNEL_MAPPING) == 0),
 	};
 
 	buf = arm_dma_buffer_find(cpu_addr);
@@ -1267,7 +1267,7 @@ static struct page **__iommu_alloc_buffer(struct device *dev, size_t size,
 	if (!pages)
 		return NULL;
 
-	if (dma_get_attr(DMA_ATTR_FORCE_CONTIGUOUS, attrs))
+	if (attrs & DMA_ATTR_FORCE_CONTIGUOUS)
 	{
 		unsigned long order = get_order(size);
 		struct page *page;
@@ -1285,7 +1285,7 @@ static struct page **__iommu_alloc_buffer(struct device *dev, size_t size,
 	}
 
 	/* Go straight to 4K chunks if caller says it's OK. */
-	if (dma_get_attr(DMA_ATTR_ALLOC_SINGLE_PAGES, attrs))
+	if (attrs & DMA_ATTR_ALLOC_SINGLE_PAGES)
 		order_idx = ARRAY_SIZE(iommu_order_array) - 1;
 
 	/*
@@ -1346,7 +1346,7 @@ static int __iommu_free_buffer(struct device *dev, struct page **pages,
 	int count = size >> PAGE_SHIFT;
 	int i;
 
-	if (dma_get_attr(DMA_ATTR_FORCE_CONTIGUOUS, attrs)) {
+	if (attrs & DMA_ATTR_FORCE_CONTIGUOUS) {
 		dma_release_from_contiguous(dev, pages[0], count);
 	} else {
 		for (i = 0; i < count; i++)
@@ -1445,7 +1445,7 @@ static struct page **__iommu_get_pages(void *cpu_addr, unsigned long attrs)
 	if (__in_atomic_pool(cpu_addr, PAGE_SIZE))
 		return __atomic_get_pages(cpu_addr);
 
-	if (dma_get_attr(DMA_ATTR_NO_KERNEL_MAPPING, attrs))
+	if (attrs & DMA_ATTR_NO_KERNEL_MAPPING)
 		return cpu_addr;
 
 	area = find_vm_area(cpu_addr);
@@ -1512,7 +1512,7 @@ static void *arm_iommu_alloc_attrs(struct device *dev, size_t size,
 	if (*handle == DMA_ERROR_CODE)
 		goto err_buffer;
 
-	if (dma_get_attr(DMA_ATTR_NO_KERNEL_MAPPING, attrs))
+	if (attrs & DMA_ATTR_NO_KERNEL_MAPPING)
 		return pages;
 
 	addr = __iommu_alloc_remap(pages, size, gfp, prot,
@@ -1583,7 +1583,7 @@ void arm_iommu_free_attrs(struct device *dev, size_t size, void *cpu_addr,
 		return;
 	}
 
-	if (!dma_get_attr(DMA_ATTR_NO_KERNEL_MAPPING, attrs)) {
+	if ((attrs & DMA_ATTR_NO_KERNEL_MAPPING) == 0) {
 		dma_common_free_remap(cpu_addr, size,
 			VM_ARM_DMA_CONSISTENT | VM_USERMAP);
 	}
@@ -1653,8 +1653,7 @@ static int __map_sg_chunk(struct device *dev, struct scatterlist *sg,
 		phys_addr_t phys = page_to_phys(sg_page(s));
 		unsigned int len = PAGE_ALIGN(s->offset + s->length);
 
-		if (!is_coherent &&
-			!dma_get_attr(DMA_ATTR_SKIP_CPU_SYNC, attrs))
+		if (!is_coherent && (attrs & DMA_ATTR_SKIP_CPU_SYNC) == 0)
 			__dma_page_cpu_to_dev(sg_page(s), s->offset, s->length, dir);
 
 		prot = __dma_direction_to_prot(dir);
@@ -1767,8 +1766,7 @@ static void __iommu_unmap_sg(struct device *dev, struct scatterlist *sg,
 		if (sg_dma_len(s))
 			__iommu_remove_mapping(dev, sg_dma_address(s),
 					       sg_dma_len(s));
-		if (!is_coherent &&
-		    !dma_get_attr(DMA_ATTR_SKIP_CPU_SYNC, attrs))
+		if (!is_coherent && (attrs & DMA_ATTR_SKIP_CPU_SYNC) == 0)
 			__dma_page_dev_to_cpu(sg_page(s), s->offset,
 					      s->length, dir);
 	}
@@ -1892,7 +1890,7 @@ static dma_addr_t arm_iommu_map_page(struct device *dev, struct page *page,
 	     unsigned long offset, size_t size, enum dma_data_direction dir,
 	     unsigned long attrs)
 {
-	if (!dma_get_attr(DMA_ATTR_SKIP_CPU_SYNC, attrs))
+	if ((attrs & DMA_ATTR_SKIP_CPU_SYNC) == 0)
 		__dma_page_cpu_to_dev(page, offset, size, dir);
 
 	return arm_coherent_iommu_map_page(dev, page, offset, size, dir, attrs);
@@ -1943,7 +1941,7 @@ static void arm_iommu_unmap_page(struct device *dev, dma_addr_t handle,
 	if (!iova)
 		return;
 
-	if (!dma_get_attr(DMA_ATTR_SKIP_CPU_SYNC, attrs))
+	if ((attrs & DMA_ATTR_SKIP_CPU_SYNC) == 0)
 		__dma_page_dev_to_cpu(page, offset, size, dir);
 
 	iommu_unmap(mapping->domain, iova, len);
diff --git a/arch/arm/xen/mm.c b/arch/arm/xen/mm.c
index fc67ed236a10..d062f08f5020 100644
--- a/arch/arm/xen/mm.c
+++ b/arch/arm/xen/mm.c
@@ -102,7 +102,7 @@ void __xen_dma_map_page(struct device *hwdev, struct page *page,
 {
 	if (is_device_dma_coherent(hwdev))
 		return;
-	if (dma_get_attr(DMA_ATTR_SKIP_CPU_SYNC, attrs))
+	if (attrs & DMA_ATTR_SKIP_CPU_SYNC)
 		return;
 
 	__xen_dma_page_cpu_to_dev(hwdev, dev_addr, size, dir);
@@ -115,7 +115,7 @@ void __xen_dma_unmap_page(struct device *hwdev, dma_addr_t handle,
 {
 	if (is_device_dma_coherent(hwdev))
 		return;
-	if (dma_get_attr(DMA_ATTR_SKIP_CPU_SYNC, attrs))
+	if (attrs & DMA_ATTR_SKIP_CPU_SYNC)
 		return;
 
 	__xen_dma_page_dev_to_cpu(hwdev, handle, size, dir);
diff --git a/arch/arm64/mm/dma-mapping.c b/arch/arm64/mm/dma-mapping.c
index a284fd0d0b00..c4284c432ae8 100644
--- a/arch/arm64/mm/dma-mapping.c
+++ b/arch/arm64/mm/dma-mapping.c
@@ -35,7 +35,7 @@ static int swiotlb __read_mostly;
 static pgprot_t __get_dma_pgprot(unsigned long attrs, pgprot_t prot,
 				 bool coherent)
 {
-	if (!coherent || dma_get_attr(DMA_ATTR_WRITE_COMBINE, attrs))
+	if (!coherent || (attrs & DMA_ATTR_WRITE_COMBINE))
 		return pgprot_writecombine(prot);
 	return prot;
 }
@@ -714,7 +714,7 @@ static dma_addr_t __iommu_map_page(struct device *dev, struct page *page,
 	dma_addr_t dev_addr = iommu_dma_map_page(dev, page, offset, size, prot);
 
 	if (!iommu_dma_mapping_error(dev, dev_addr) &&
-	    !dma_get_attr(DMA_ATTR_SKIP_CPU_SYNC, attrs))
+	    (attrs & DMA_ATTR_SKIP_CPU_SYNC) == 0)
 		__iommu_sync_single_for_device(dev, dev_addr, size, dir);
 
 	return dev_addr;
@@ -724,7 +724,7 @@ static void __iommu_unmap_page(struct device *dev, dma_addr_t dev_addr,
 			       size_t size, enum dma_data_direction dir,
 			       unsigned long attrs)
 {
-	if (!dma_get_attr(DMA_ATTR_SKIP_CPU_SYNC, attrs))
+	if ((attrs & DMA_ATTR_SKIP_CPU_SYNC) == 0)
 		__iommu_sync_single_for_cpu(dev, dev_addr, size, dir);
 
 	iommu_dma_unmap_page(dev, dev_addr, size, dir, attrs);
@@ -764,7 +764,7 @@ static int __iommu_map_sg_attrs(struct device *dev, struct scatterlist *sgl,
 {
 	bool coherent = is_device_dma_coherent(dev);
 
-	if (!dma_get_attr(DMA_ATTR_SKIP_CPU_SYNC, attrs))
+	if ((attrs & DMA_ATTR_SKIP_CPU_SYNC) == 0)
 		__iommu_sync_sg_for_device(dev, sgl, nelems, dir);
 
 	return iommu_dma_map_sg(dev, sgl, nelems,
@@ -776,7 +776,7 @@ static void __iommu_unmap_sg_attrs(struct device *dev,
 				   enum dma_data_direction dir,
 				   unsigned long attrs)
 {
-	if (!dma_get_attr(DMA_ATTR_SKIP_CPU_SYNC, attrs))
+	if ((attrs & DMA_ATTR_SKIP_CPU_SYNC) == 0)
 		__iommu_sync_sg_for_cpu(dev, sgl, nelems, dir);
 
 	iommu_dma_unmap_sg(dev, sgl, nelems, dir, attrs);
diff --git a/arch/avr32/mm/dma-coherent.c b/arch/avr32/mm/dma-coherent.c
index fc51f4421933..58610d0df7ed 100644
--- a/arch/avr32/mm/dma-coherent.c
+++ b/arch/avr32/mm/dma-coherent.c
@@ -109,7 +109,7 @@ static void *avr32_dma_alloc(struct device *dev, size_t size,
 		return NULL;
 	phys = page_to_phys(page);
 
-	if (dma_get_attr(DMA_ATTR_WRITE_COMBINE, attrs)) {
+	if (attrs & DMA_ATTR_WRITE_COMBINE) {
 		/* Now, map the page into P3 with write-combining turned on */
 		*handle = phys;
 		return __ioremap(phys, size, _PAGE_BUFFER);
@@ -123,7 +123,7 @@ static void avr32_dma_free(struct device *dev, size_t size,
 {
 	struct page *page;
 
-	if (dma_get_attr(DMA_ATTR_WRITE_COMBINE, attrs)) {
+	if (attrs & DMA_ATTR_WRITE_COMBINE) {
 		iounmap(cpu_addr);
 
 		page = phys_to_page(handle);
diff --git a/arch/ia64/sn/pci/pci_dma.c b/arch/ia64/sn/pci/pci_dma.c
index 6b78fc953c4b..74c934a997bb 100644
--- a/arch/ia64/sn/pci/pci_dma.c
+++ b/arch/ia64/sn/pci/pci_dma.c
@@ -183,14 +183,11 @@ static dma_addr_t sn_dma_map_page(struct device *dev, struct page *page,
 	unsigned long phys_addr;
 	struct pci_dev *pdev = to_pci_dev(dev);
 	struct sn_pcibus_provider *provider = SN_PCIDEV_BUSPROVIDER(pdev);
-	int dmabarr;
-
-	dmabarr = dma_get_attr(DMA_ATTR_WRITE_BARRIER, attrs);
 
 	BUG_ON(!dev_is_pci(dev));
 
 	phys_addr = __pa(cpu_addr);
-	if (dmabarr)
+	if (attrs & DMA_ATTR_WRITE_BARRIER)
 		dma_addr = provider->dma_map_consistent(pdev, phys_addr,
 							size, SN_DMA_ADDR_PHYS);
 	else
@@ -280,9 +277,6 @@ static int sn_dma_map_sg(struct device *dev, struct scatterlist *sgl,
 	struct pci_dev *pdev = to_pci_dev(dev);
 	struct sn_pcibus_provider *provider = SN_PCIDEV_BUSPROVIDER(pdev);
 	int i;
-	int dmabarr;
-
-	dmabarr = dma_get_attr(DMA_ATTR_WRITE_BARRIER, attrs);
 
 	BUG_ON(!dev_is_pci(dev));
 
@@ -292,7 +286,7 @@ static int sn_dma_map_sg(struct device *dev, struct scatterlist *sgl,
 	for_each_sg(sgl, sg, nhwentries, i) {
 		dma_addr_t dma_addr;
 		phys_addr = SG_ENT_PHYS_ADDRESS(sg);
-		if (dmabarr)
+		if (attrs & DMA_ATTR_WRITE_BARRIER)
 			dma_addr = provider->dma_map_consistent(pdev,
 								phys_addr,
 								sg->length,
diff --git a/arch/metag/kernel/dma.c b/arch/metag/kernel/dma.c
index d68f498e82a1..0db31e24c541 100644
--- a/arch/metag/kernel/dma.c
+++ b/arch/metag/kernel/dma.c
@@ -337,7 +337,7 @@ static int metag_dma_mmap(struct device *dev, struct vm_area_struct *vma,
 	struct metag_vm_region *c;
 	int ret = -ENXIO;
 
-	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);
diff --git a/arch/mips/mm/dma-default.c b/arch/mips/mm/dma-default.c
index 0ed9000dc1ff..b2eadd6fa9a1 100644
--- a/arch/mips/mm/dma-default.c
+++ b/arch/mips/mm/dma-default.c
@@ -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);
@@ -182,7 +182,7 @@ static void mips_dma_free_coherent(struct device *dev, size_t size, void *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;
 	}
@@ -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);
diff --git a/arch/openrisc/kernel/dma.c b/arch/openrisc/kernel/dma.c
index 50eb1f26c540..140c99140649 100644
--- a/arch/openrisc/kernel/dma.c
+++ b/arch/openrisc/kernel/dma.c
@@ -100,7 +100,7 @@ or1k_dma_alloc(struct device *dev, size_t size,
 
 	va = (unsigned long)page;
 
-	if (!dma_get_attr(DMA_ATTR_NON_CONSISTENT, attrs)) {
+	if ((attrs & DMA_ATTR_NON_CONSISTENT) == 0) {
 		/*
 		 * We need to iterate through the pages, clearing the dcache for
 		 * them and setting the cache-inhibit bit.
@@ -124,7 +124,7 @@ or1k_dma_free(struct device *dev, size_t size, void *vaddr,
 		.mm = &init_mm
 	};
 
-	if (!dma_get_attr(DMA_ATTR_NON_CONSISTENT, attrs)) {
+	if ((attrs & DMA_ATTR_NON_CONSISTENT) == 0) {
 		/* walk_page_range shouldn't be able to fail here */
 		WARN_ON(walk_page_range(va, va + size, &walk));
 	}
diff --git a/arch/parisc/kernel/pci-dma.c b/arch/parisc/kernel/pci-dma.c
index 845fdd52e4c5..02d9ed0f3949 100644
--- a/arch/parisc/kernel/pci-dma.c
+++ b/arch/parisc/kernel/pci-dma.c
@@ -581,7 +581,7 @@ static void *pcx_dma_alloc(struct device *dev, size_t size,
 {
 	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));
diff --git a/arch/powerpc/platforms/cell/iommu.c b/arch/powerpc/platforms/cell/iommu.c
index 9a195f1893af..f7d1a4953ea0 100644
--- a/arch/powerpc/platforms/cell/iommu.c
+++ b/arch/powerpc/platforms/cell/iommu.c
@@ -193,7 +193,7 @@ static int tce_build_cell(struct iommu_table *tbl, long index, long npages,
 	base_pte = CBE_IOPTE_PP_W | CBE_IOPTE_PP_R | CBE_IOPTE_M |
 		CBE_IOPTE_SO_RW | (window->ioid & CBE_IOPTE_IOID_Mask);
 #endif
-	if (unlikely(dma_get_attr(DMA_ATTR_WEAK_ORDERING, attrs)))
+	if (unlikely(attrs & DMA_ATTR_WEAK_ORDERING))
 		base_pte &= ~CBE_IOPTE_SO_RW;
 
 	io_pte = (unsigned long *)tbl->it_base + (index - tbl->it_offset);
@@ -600,7 +600,7 @@ static dma_addr_t dma_fixed_map_page(struct device *dev, struct page *page,
 				     enum dma_data_direction direction,
 				     unsigned long attrs)
 {
-	if (iommu_fixed_is_weak == dma_get_attr(DMA_ATTR_WEAK_ORDERING, attrs))
+	if (iommu_fixed_is_weak == (attrs & DMA_ATTR_WEAK_ORDERING))
 		return dma_direct_ops.map_page(dev, page, offset, size,
 					       direction, attrs);
 	else
@@ -613,7 +613,7 @@ static void dma_fixed_unmap_page(struct device *dev, dma_addr_t dma_addr,
 				 size_t size, enum dma_data_direction direction,
 				 unsigned long attrs)
 {
-	if (iommu_fixed_is_weak == dma_get_attr(DMA_ATTR_WEAK_ORDERING, attrs))
+	if (iommu_fixed_is_weak == (attrs & DMA_ATTR_WEAK_ORDERING))
 		dma_direct_ops.unmap_page(dev, dma_addr, size, direction,
 					  attrs);
 	else
@@ -625,7 +625,7 @@ static int dma_fixed_map_sg(struct device *dev, struct scatterlist *sg,
 			   int nents, enum dma_data_direction direction,
 			   unsigned long attrs)
 {
-	if (iommu_fixed_is_weak == dma_get_attr(DMA_ATTR_WEAK_ORDERING, attrs))
+	if (iommu_fixed_is_weak == (attrs & DMA_ATTR_WEAK_ORDERING))
 		return dma_direct_ops.map_sg(dev, sg, nents, direction, attrs);
 	else
 		return ppc_iommu_map_sg(dev, cell_get_iommu_table(dev), sg,
@@ -637,7 +637,7 @@ static void dma_fixed_unmap_sg(struct device *dev, struct scatterlist *sg,
 			       int nents, enum dma_data_direction direction,
 			       unsigned long attrs)
 {
-	if (iommu_fixed_is_weak == dma_get_attr(DMA_ATTR_WEAK_ORDERING, attrs))
+	if (iommu_fixed_is_weak == (attrs & DMA_ATTR_WEAK_ORDERING))
 		dma_direct_ops.unmap_sg(dev, sg, nents, direction, attrs);
 	else
 		ppc_iommu_unmap_sg(cell_get_iommu_table(dev), sg, nents,
@@ -1162,7 +1162,7 @@ static int __init setup_iommu_fixed(char *str)
 	pciep = of_find_node_by_type(NULL, "pcie-endpoint");
 
 	if (strcmp(str, "weak") == 0 || (pciep && strcmp(str, "strong") != 0))
-		iommu_fixed_is_weak = 1;
+		iommu_fixed_is_weak = DMA_ATTR_WEAK_ORDERING;
 
 	of_node_put(pciep);
 
diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_gem.c b/drivers/gpu/drm/rockchip/rockchip_drm_gem.c
index 28b2a828c650..b70f9423379c 100644
--- a/drivers/gpu/drm/rockchip/rockchip_drm_gem.c
+++ b/drivers/gpu/drm/rockchip/rockchip_drm_gem.c
@@ -273,7 +273,7 @@ void *rockchip_gem_prime_vmap(struct drm_gem_object *obj)
 {
 	struct rockchip_gem_object *rk_obj = to_rockchip_obj(obj);
 
-	if (dma_get_attr(DMA_ATTR_NO_KERNEL_MAPPING, rk_obj->dma_attrs))
+	if (rk_obj->dma_attrs & DMA_ATTR_NO_KERNEL_MAPPING)
 		return NULL;
 
 	return rk_obj->kvaddr;
diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c
index 6c1bda504fb1..08a1e2f3690f 100644
--- a/drivers/iommu/dma-iommu.c
+++ b/drivers/iommu/dma-iommu.c
@@ -306,7 +306,7 @@ struct page **iommu_dma_alloc(struct device *dev, size_t size, gfp_t gfp,
 	} else {
 		size = ALIGN(size, min_size);
 	}
-	if (dma_get_attr(DMA_ATTR_ALLOC_SINGLE_PAGES, attrs))
+	if (attrs & DMA_ATTR_ALLOC_SINGLE_PAGES)
 		alloc_sizes = min_size;
 
 	count = PAGE_ALIGN(size) >> PAGE_SHIFT;
diff --git a/drivers/media/v4l2-core/videobuf2-dma-contig.c b/drivers/media/v4l2-core/videobuf2-dma-contig.c
index 1ec4434a86bb..b09b2c9b6b63 100644
--- a/drivers/media/v4l2-core/videobuf2-dma-contig.c
+++ b/drivers/media/v4l2-core/videobuf2-dma-contig.c
@@ -155,7 +155,7 @@ static void *vb2_dc_alloc(struct device *dev, unsigned long attrs,
 		return ERR_PTR(-ENOMEM);
 	}
 
-	if (!dma_get_attr(DMA_ATTR_NO_KERNEL_MAPPING, buf->attrs))
+	if ((buf->attrs & DMA_ATTR_NO_KERNEL_MAPPING) == 0)
 		buf->vaddr = buf->cookie;
 
 	/* Prevent the device from being released while the buffer is used */
diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h
index 1fd9860487b1..d8fb67783cb7 100644
--- a/include/linux/dma-mapping.h
+++ b/include/linux/dma-mapping.h
@@ -101,16 +101,6 @@ static inline int is_device_dma_capable(struct device *dev)
 	return dev->dma_mask != NULL && *dev->dma_mask != DMA_MASK_NONE;
 }
 
-/**
- * dma_get_attr - check for a specific attribute
- * @attr: attribute to look for
- * @attrs: attributes to check within
- */
-static inline bool dma_get_attr(unsigned long attr, unsigned long attrs)
-{
-	return !!(attr & attrs);
-}
-
 #ifdef CONFIG_HAVE_GENERIC_DMA_COHERENT
 /*
  * These three functions are only for dma allocator.
-- 
1.9.1