diff options
author | Krzysztof Kozlowski | 2016-08-03 22:46:00 +0200 |
---|---|---|
committer | Linus Torvalds | 2016-08-04 14:50:07 +0200 |
commit | 00085f1efa387a8ce100e3734920f7639c80caa3 (patch) | |
tree | 41ff3d6e6884918b4fc4f1ae96a284098167c5b0 /include/linux/dma-attrs.h | |
parent | media: mtk-vcodec: remove unused dma_attrs (diff) | |
download | kernel-qcow2-linux-00085f1efa387a8ce100e3734920f7639c80caa3.tar.gz kernel-qcow2-linux-00085f1efa387a8ce100e3734920f7639c80caa3.tar.xz kernel-qcow2-linux-00085f1efa387a8ce100e3734920f7639c80caa3.zip |
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>
Diffstat (limited to 'include/linux/dma-attrs.h')
-rw-r--r-- | include/linux/dma-attrs.h | 71 |
1 files changed, 0 insertions, 71 deletions
diff --git a/include/linux/dma-attrs.h b/include/linux/dma-attrs.h deleted file mode 100644 index 5246239a4953..000000000000 --- a/include/linux/dma-attrs.h +++ /dev/null @@ -1,71 +0,0 @@ -#ifndef _DMA_ATTR_H -#define _DMA_ATTR_H - -#include <linux/bitmap.h> -#include <linux/bitops.h> -#include <linux/bug.h> - -/** - * an enum dma_attr represents an attribute associated with a DMA - * mapping. The semantics of each attribute should be defined in - * Documentation/DMA-attributes.txt. - */ -enum dma_attr { - DMA_ATTR_WRITE_BARRIER, - DMA_ATTR_WEAK_ORDERING, - DMA_ATTR_WRITE_COMBINE, - DMA_ATTR_NON_CONSISTENT, - DMA_ATTR_NO_KERNEL_MAPPING, - DMA_ATTR_SKIP_CPU_SYNC, - DMA_ATTR_FORCE_CONTIGUOUS, - DMA_ATTR_ALLOC_SINGLE_PAGES, - DMA_ATTR_MAX, -}; - -#define __DMA_ATTRS_LONGS BITS_TO_LONGS(DMA_ATTR_MAX) - -/** - * struct dma_attrs - an opaque container for DMA attributes - * @flags - bitmask representing a collection of enum dma_attr - */ -struct dma_attrs { - unsigned long flags[__DMA_ATTRS_LONGS]; -}; - -#define DEFINE_DMA_ATTRS(x) \ - struct dma_attrs x = { \ - .flags = { [0 ... __DMA_ATTRS_LONGS-1] = 0 }, \ - } - -static inline void init_dma_attrs(struct dma_attrs *attrs) -{ - bitmap_zero(attrs->flags, __DMA_ATTRS_LONGS); -} - -/** - * dma_set_attr - set a specific attribute - * @attr: attribute to set - * @attrs: struct dma_attrs (may be NULL) - */ -static inline void dma_set_attr(enum dma_attr attr, struct dma_attrs *attrs) -{ - if (attrs == NULL) - return; - BUG_ON(attr >= DMA_ATTR_MAX); - __set_bit(attr, attrs->flags); -} - -/** - * dma_get_attr - check for a specific attribute - * @attr: attribute to set - * @attrs: struct dma_attrs (may be NULL) - */ -static inline int dma_get_attr(enum dma_attr attr, struct dma_attrs *attrs) -{ - if (attrs == NULL) - return 0; - BUG_ON(attr >= DMA_ATTR_MAX); - return test_bit(attr, attrs->flags); -} - -#endif /* _DMA_ATTR_H */ |