xiuos/Ubiquitous/XiZi_AIoT/softkernel/include/bitmap64.h

68 lines
1.7 KiB
C

/*
* Copyright (c) 2020 AIIT XUOS Lab
* XiUOS is licensed under Mulan PSL v2.
* You can use this software according to the terms and conditions of the Mulan PSL v2.
* You may obtain a copy of Mulan PSL v2 at:
* http://license.coscl.org.cn/MulanPSL2
* THIS SOFTWARE IS PROVIDED ON AN "AS IS" BASIS, WITHOUT WARRANTIES OF ANY KIND,
* EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO NON-INFRINGEMENT,
* MERCHANTABILITY OR FIT FOR A PARTICULAR PURPOSE.
* See the Mulan PSL v2 for more details.
*/
/**
* @file bitmap64.h
* @brief 64 bit bitmap support
* @version 3.0
* @author AIIT XUOS Lab
* @date 2023.08.25
*/
/*************************************************
File name: bitmap64.h
Description: 64 bit bitmap support
Others:
History:
1. Date: 2024-05-18
Author: AIIT XUOS Lab
Modification:
1. first version
*************************************************/
#pragma once
#include <stddef.h>
#include <stdint.h>
#include "assert.h"
struct bitmap64 {
uint64_t map;
};
static inline void bitmap64_init(struct bitmap64* bitmap)
{
bitmap->map = 0;
}
static inline int bitmap64_alloc(struct bitmap64* bitmap)
{
int free_bit = -1;
// free bit is the first 0 bit, from [1, 64]
free_bit = __builtin_ffsl(~(uint64_t)(bitmap->map));
// handle if bitmap is full (no using 64th bit here)
if (free_bit == 0) {
return -1;
}
assert(free_bit < 64 && free_bit >= 1);
// alloc and return
bitmap->map |= (1 << (free_bit - 1));
return free_bit - 1;
}
static inline void bitmap64_free(struct bitmap64* bitmap, int idx)
{
// usages of bitmap64 must be correct
assert((bitmap->map & (1 << idx)) != 0);
// free bit
bitmap->map &= ~(uint64_t)(1 << idx);
}