io.c

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#include <kernel/cpu/io.h>
#include <kernel/sync/lock.h>
 
#include <kernel/log/log.h>
 
#include <errno.h>
#include <stdbool.h>
#include <stddef.h>
#include <sys/bitmap.h>
#include <sys/list.h>
 
static BITMAP_CREATE(ports, IO_PORT_MAX + 1);
static lock_t lock = LOCK_CREATE();
 
uint64_t io_reserve(port_t* out, port_t minBase, port_t maxBase, uint64_t alignment, uint64_t length, const char* owner)
{
    (void)owner;
 
    if (out == NULL || length == 0 || minBase > maxBase)
    {
        errno = EINVAL;
        return ERR;
    }
    LOCK_SCOPE(&lock);
 
    if (maxBase + length < maxBase || maxBase + length > ports.length)
    {
        errno = EOVERFLOW;
        return ERR;
    }
 
    uint64_t base = bitmap_find_clear_region_and_set(&ports, minBase, maxBase + length, length, alignment);
    if (base == ports.length)
    {
        errno = ENOSPC;
        return ERR;
    }
 
    *out = (port_t)base;
    return 0;
}
 
void io_release(port_t base, uint64_t length)
{
    if (length == 0 || base + length < base || base + length > ports.length)
    {
        return;
    }
    LOCK_SCOPE(&lock);
 
    bitmap_clear_range(&ports, base, base + length);
}