mirror_ubuntu-kernels/include/linux/util_macros.h

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2024-07-02 00:48:40 +03:00
/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _LINUX_HELPER_MACROS_H_
#define _LINUX_HELPER_MACROS_H_
#include <linux/math.h>
#define __find_closest(x, a, as, op) \
({ \
typeof(as) __fc_i, __fc_as = (as) - 1; \
typeof(x) __fc_x = (x); \
typeof(*a) const *__fc_a = (a); \
for (__fc_i = 0; __fc_i < __fc_as; __fc_i++) { \
if (__fc_x op DIV_ROUND_CLOSEST(__fc_a[__fc_i] + \
__fc_a[__fc_i + 1], 2)) \
break; \
} \
(__fc_i); \
})
/**
* find_closest - locate the closest element in a sorted array
* @x: The reference value.
* @a: The array in which to look for the closest element. Must be sorted
* in ascending order.
* @as: Size of 'a'.
*
* Returns the index of the element closest to 'x'.
*/
#define find_closest(x, a, as) __find_closest(x, a, as, <=)
/**
* find_closest_descending - locate the closest element in a sorted array
* @x: The reference value.
* @a: The array in which to look for the closest element. Must be sorted
* in descending order.
* @as: Size of 'a'.
*
* Similar to find_closest() but 'a' is expected to be sorted in descending
* order.
*/
#define find_closest_descending(x, a, as) __find_closest(x, a, as, >=)
/**
* is_insidevar - check if the @ptr points inside the @var memory range.
* @ptr: the pointer to a memory address.
* @var: the variable which address and size identify the memory range.
*
* Evaluates to true if the address in @ptr lies within the memory
* range allocated to @var.
*/
#define is_insidevar(ptr, var) \
((uintptr_t)(ptr) >= (uintptr_t)(var) && \
(uintptr_t)(ptr) < (uintptr_t)(var) + sizeof(var))
#endif