4 #include <linux/bitmap.h>
5 #include <linux/bitops.h>
9 * an enum dma_attr represents an attribute associated with a DMA
10 * mapping. The semantics of each attribute should be defined in
11 * Documentation/DMA-attributes.txt.
14 DMA_ATTR_WRITE_BARRIER,
15 DMA_ATTR_WEAK_ORDERING,
16 DMA_ATTR_WRITE_COMBINE,
17 DMA_ATTR_NON_CONSISTENT,
18 DMA_ATTR_NO_KERNEL_MAPPING,
22 #define __DMA_ATTRS_LONGS BITS_TO_LONGS(DMA_ATTR_MAX)
25 * struct dma_attrs - an opaque container for DMA attributes
26 * @flags - bitmask representing a collection of enum dma_attr
29 unsigned long flags[__DMA_ATTRS_LONGS];
32 #define DEFINE_DMA_ATTRS(x) \
33 struct dma_attrs x = { \
34 .flags = { [0 ... __DMA_ATTRS_LONGS-1] = 0 }, \
37 static inline void init_dma_attrs(struct dma_attrs *attrs)
39 bitmap_zero(attrs->flags, __DMA_ATTRS_LONGS);
42 #ifdef CONFIG_HAVE_DMA_ATTRS
44 * dma_set_attr - set a specific attribute
45 * @attr: attribute to set
46 * @attrs: struct dma_attrs (may be NULL)
48 static inline void dma_set_attr(enum dma_attr attr, struct dma_attrs *attrs)
52 BUG_ON(attr >= DMA_ATTR_MAX);
53 __set_bit(attr, attrs->flags);
57 * dma_get_attr - check for a specific attribute
58 * @attr: attribute to set
59 * @attrs: struct dma_attrs (may be NULL)
61 static inline int dma_get_attr(enum dma_attr attr, struct dma_attrs *attrs)
65 BUG_ON(attr >= DMA_ATTR_MAX);
66 return test_bit(attr, attrs->flags);
68 #else /* !CONFIG_HAVE_DMA_ATTRS */
69 static inline void dma_set_attr(enum dma_attr attr, struct dma_attrs *attrs)
73 static inline int dma_get_attr(enum dma_attr attr, struct dma_attrs *attrs)
77 #endif /* CONFIG_HAVE_DMA_ATTRS */
78 #endif /* _DMA_ATTR_H */