[deliverable/linux.git] / include / linux / dma-attrs.h

#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_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 */
Commit	Line	Data
74bc7cee AK	1	#ifndef _DMA_ATTR_H
	2	#define _DMA_ATTR_H
	3
	4	#include <linux/bitmap.h>
	5	#include <linux/bitops.h>
	6	#include <linux/bug.h>
	7
	8	/**
	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.
	12	*/
	13	enum dma_attr {
	14	DMA_ATTR_WRITE_BARRIER,
1ed6af73	15	DMA_ATTR_WEAK_ORDERING,
8a413432	16	DMA_ATTR_WRITE_COMBINE,
64d70fe5	17	DMA_ATTR_NON_CONSISTENT,
d5724f17	18	DMA_ATTR_NO_KERNEL_MAPPING,
bdf5e487	19	DMA_ATTR_SKIP_CPU_SYNC,
4b9347dc	20	DMA_ATTR_FORCE_CONTIGUOUS,
74bc7cee AK	21	DMA_ATTR_MAX,
	22	};
	23
	24	#define __DMA_ATTRS_LONGS BITS_TO_LONGS(DMA_ATTR_MAX)
	25
	26	/**
	27	* struct dma_attrs - an opaque container for DMA attributes
	28	* @flags - bitmask representing a collection of enum dma_attr
	29	*/
	30	struct dma_attrs {
	31	unsigned long flags[__DMA_ATTRS_LONGS];
	32	};
	33
	34	#define DEFINE_DMA_ATTRS(x) \
	35	struct dma_attrs x = { \
	36	.flags = { [0 ... __DMA_ATTRS_LONGS-1] = 0 }, \
	37	}
	38
	39	static inline void init_dma_attrs(struct dma_attrs *attrs)
	40	{
	41	bitmap_zero(attrs->flags, __DMA_ATTRS_LONGS);
	42	}
	43
74bc7cee AK	44	/**
	45	* dma_set_attr - set a specific attribute
	46	* @attr: attribute to set
	47	* @attrs: struct dma_attrs (may be NULL)
	48	*/
	49	static inline void dma_set_attr(enum dma_attr attr, struct dma_attrs *attrs)
	50	{
	51	if (attrs == NULL)
	52	return;
	53	BUG_ON(attr >= DMA_ATTR_MAX);
	54	__set_bit(attr, attrs->flags);
	55	}
	56
	57	/**
	58	* dma_get_attr - check for a specific attribute
	59	* @attr: attribute to set
	60	* @attrs: struct dma_attrs (may be NULL)
	61	*/
	62	static inline int dma_get_attr(enum dma_attr attr, struct dma_attrs *attrs)
	63	{
	64	if (attrs == NULL)
	65	return 0;
	66	BUG_ON(attr >= DMA_ATTR_MAX);
	67	return test_bit(attr, attrs->flags);
	68	}
74bc7cee	69
74bc7cee	70	#endif /* _DMA_ATTR_H */