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#ifndef _LINUX_ALIGN_H
#define _LINUX_ALIGN_H
#define __ALIGN_KERNEL(x, a) __ALIGN_KERNEL_MASK(x, (typeof(x))(a) - 1)
#define __ALIGN_KERNEL_MASK(x, mask) \
(((x) + (mask)) & ~(mask))
#ifdef __KERNEL__
#include <linux/types.h>
#define ALIGN(x, a) __ALIGN_KERNEL(x, a)
#define __ALIGN_MASK(x, mask) __ALIGN_KERNEL_MASK(x, mask)
#define PTR_ALIGN(p, a) ((typeof(p)) ALIGN((unsigned long) (p), a))
#define ALIGN_FLOOR(x, a) __ALIGN_FLOOR_MASK(x, (typeof(x)) (a) - 1)
#define __ALIGN_FLOOR_MASK(x, mask) ((x) & ~(mask))
#define PTR_ALIGN_FLOOR(p, a) \
((typeof(p)) ALIGN_FLOOR((unsigned long) (p), a))
#define IS_ALIGNED(x, a) (((x) & ((typeof(x)) (a) - 1)) == 0)
/*
* Align pointer on natural object alignment.
*/
#define object_align(obj) PTR_ALIGN(obj, __alignof__(*(obj)))
#define object_align_floor(obj) PTR_ALIGN_FLOOR(obj, __alignof__(*(obj)))
#define MAYBE_BUILD_BUG_ON(condition) \
do { \
if (__builtin_constant_p(condition)) \
BUILD_BUG_ON(condition); \
} while (0)
/**
* offset_align - Calculate the offset needed to align an object on its natural
* alignment towards higher addresses.
* @align_drift: object offset from an "alignment"-aligned address.
* @alignment: natural object alignment. Must be non-zero, power of 2.
*
* Returns the offset that must be added to align towards higher
* addresses.
*/
#define offset_align(align_drift, alignment) \
({ \
MAYBE_BUILD_BUG_ON((alignment) == 0 \
|| ((alignment) & ((alignment) - 1))); \
(((alignment) - (align_drift)) & ((alignment) - 1)); \
})
/**
* offset_align_floor - Calculate the offset needed to align an object
* on its natural alignment towards lower addresses.
* @align_drift: object offset from an "alignment"-aligned address.
* @alignment: natural object alignment. Must be non-zero, power of 2.
*
* Returns the offset that must be substracted to align towards lower addresses.
*/
#define offset_align_floor(align_drift, alignment) \
({ \
MAYBE_BUILD_BUG_ON((alignment) == 0 \
|| ((alignment) & ((alignment) - 1))); \
(((align_drift) - (alignment)) & ((alignment) - 1); \
})
#endif /* __KERNEL__ */
#endif
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