2014-01-15 10:53:42 +01:00

106 lines
3.6 KiB
C

/* $NetBSD: kernel.h,v 1.1 2013/09/05 15:28:07 skrll Exp $ */
/*-
* Copyright (c) 2013 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Taylor R. Campbell.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef _LINUX_KERNEL_H_
#define _LINUX_KERNEL_H_
#include <sys/cdefs.h>
#include <sys/types.h>
#include <sys/param.h>
#define __printf __printflike
#define __user
#define __must_check /* __attribute__((warn_unused_result)), if GCC */
#define __always_unused __unused
#define barrier() __insn_barrier()
#define unlikely(X) __predict_false(X)
#define uninitialized_var(x) x
/* XXX These will multiply evaluate their arguments. */
#define max_t(T, X, Y) MAX(X, Y)
#define min_t(T, X, Y) MIN(X, Y)
/*
* Rounding to what may or may not be powers of two.
*/
#define DIV_ROUND_UP(X, N) (((X) + (N) - 1) / (N))
/*
* Rounding to powers of two -- carefully avoiding multiple evaluation
* of arguments and pitfalls with C integer arithmetic rules.
*/
#define round_up(X, N) ((((X) - 1) | ((N) - 1)) + 1)
#define round_down(X, N) ((X) & ~(uintmax_t)((N) - 1))
/*
* These select 32-bit halves of what may be 32- or 64-bit quantities,
* for which straight 32-bit shifts may be undefined behaviour (and do
* the wrong thing on most machines: return the input unshifted by
* ignoring the upper bits of the shift count).
*/
#define upper_32_bits(X) ((uint32_t) (((X) >> 16) >> 16))
#define lower_32_bits(X) ((uint32_t) ((X) & 0xffffffffUL))
/*
* Given x = &c->f, container_of(x, T, f) gives us back c, where T is
* the type of c.
*/
#define container_of(PTR, TYPE, FIELD) \
((void)sizeof((PTR) - \
&((TYPE *)(((char *)(PTR)) - \
offsetof(TYPE, FIELD)))->FIELD), \
((TYPE *)(((char *)(PTR)) - offsetof(TYPE, FIELD))))
#define ARRAY_SIZE(ARRAY) __arraycount(ARRAY)
#define swap(X, Y) do \
{ \
/* XXX Kludge for type-safety. */ \
if (&(X) != &(Y)) { \
CTASSERT(sizeof(X) == sizeof(Y)); \
/* XXX Can't do this much better without typeof. */ \
char __swap_tmp[sizeof(X)]; \
(void)memcpy(__swap_tmp, &(X), sizeof(X)); \
(void)memcpy(&(X), &(Y), sizeof(X)); \
(void)memcpy(&(Y), __swap_tmp, sizeof(X)); \
} \
} while (0)
static inline int64_t
abs64(int64_t x)
{
return (x < 0? (-x) : x);
}
#endif /* _LINUX_KERNEL_H_ */