opnsense-src/sys/compat/linuxkpi/common/include/linux/math.h
Lutz Bichler 872c817d52 linuxkpi: Correct DIV_ROUND_DOWN_ULL
This fixes a black screen issue with the i915 DRM driver from Linux v6.8

Fixes: c4e0746e7d ("LinuxKPI: Add helper macros IS_ALIGNED and DIV_ROUND_DOWN_ULL.")
Pull request: https://github.com/freebsd/freebsd-src/pull/1612

(cherry picked from commit ef037a028af7cc331e36ca6c8e2eb5612cdb1130)
2025-03-18 09:27:37 -04:00

76 lines
2.9 KiB
C

/*-
* SPDX-License-Identifier: BSD-2-Clause
*
* Copyright (c) 2013-2015 Mellanox Technologies, Ltd.
* Copyright (c) 2014-2015 François Tigeot
* Copyright (c) 2016 Matt Macy <mmacy@FreeBSD.org>
* Copyright (c) 2019 Johannes Lundberg <johalun@FreeBSD.org>
* Copyright (c) 2023 Serenity Cyber Security, LLC.
*
* 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 AUTHOR 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 AUTHOR 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 _LINUXKPI_LINUX_MATH_H_
#define _LINUXKPI_LINUX_MATH_H_
#include <linux/types.h>
/*
* This looks more complex than it should be. But we need to
* get the type for the ~ right in round_down (it needs to be
* as wide as the result!), and we want to evaluate the macro
* arguments just once each.
*/
#define __round_mask(x, y) ((__typeof__(x))((y)-1))
#define round_up(x, y) ((((x)-1) | __round_mask(x, y))+1)
#define round_down(x, y) ((x) & ~__round_mask(x, y))
#define DIV_ROUND_UP(x, n) howmany(x, n)
#define DIV_ROUND_UP_ULL(x, n) DIV_ROUND_UP((unsigned long long)(x), (n))
#define DIV_ROUND_DOWN_ULL(x, n) ((unsigned long long)(x) / (n))
#define DIV_ROUND_CLOSEST(x, divisor) (((x) + ((divisor) / 2)) / (divisor))
#define DIV_ROUND_CLOSEST_ULL(x, divisor) ({ \
__typeof(divisor) __d = (divisor); \
unsigned long long __ret = (x) + (__d) / 2; \
__ret /= __d; \
__ret; \
})
#if defined(LINUXKPI_VERSION) && LINUXKPI_VERSION >= 60600
#define abs_diff(x, y) ({ \
__typeof(x) _x = (x); \
__typeof(y) _y = (y); \
_x > _y ? _x - _y : _y - _x; \
})
#endif
static inline uintmax_t
mult_frac(uintmax_t x, uintmax_t multiplier, uintmax_t divisor)
{
uintmax_t q = (x / divisor);
uintmax_t r = (x % divisor);
return ((q * multiplier) + ((r * multiplier) / divisor));
}
#endif /* _LINUXKPI_LINUX_MATH_H_ */