Function bitmap_region_alloc

components/drivers/pci/endpoint/mem.c:90–205

}

static rt_ubase_t bitmap_region_alloc(struct rt_pci_ep_mem *mem, rt_size_t size)
{
    rt_size_t bit, next_bit, end_bit, max_bits;

    size /= mem->page_size;
    max_bits = mem->bits - size;

    rt_bitmap_for_each_clear_bit(mem->map, bit, max_bits)
    {
        end_bit = bit + size;

        for (next_bit = bit + 1; next_bit < end_bit; ++next_bit)
        {
            if (rt_bitmap_test_bit(mem->map, next_bit))
            {
                bit = next_bit;
                goto _next;
            }
        }

        if (next_bit == end_bit)
        {
            while (next_bit --> bit)
            {
                rt_bitmap_set_bit(mem->map, next_bit);
            }

            return mem->cpu_addr + bit * mem->page_size;
        }
    _next:
    }

    return ~0ULL;
}

static void bitmap_region_free(struct rt_pci_ep_mem *mem,
        rt_ubase_t cpu_addr, rt_size_t size)
{
    rt_size_t bit = (cpu_addr - mem->cpu_addr) / mem->page_size, end_bit;

    size /= mem->page_size;
    end_bit = bit + size;

    for (; bit < end_bit; ++bit)
    {
        rt_bitmap_clear_bit(mem->map, bit);
    }
}

void *rt_pci_ep_mem_alloc(struct rt_pci_ep *ep,
        rt_ubase_t *out_cpu_addr, rt_size_t size)
{
    void *vaddr = RT_NULL;

    if (!ep || !out_cpu_addr)
    {
        return vaddr;
    }