Function _do_prefetch

components/mm/mm_aspace.c:245–278

allocate memory page for mapping range */

/* allocate memory page for mapping range */
static int _do_prefetch(rt_aspace_t aspace, rt_varea_t varea, void *start,
                        rt_size_t size)
{
    int err = RT_EOK;

    /* it's ensured by caller that start & size ara page-aligned */
    char *end = (char *)start + size;
    char *vaddr = start;
    rt_size_t off = varea->offset + ((vaddr - (char *)varea->start) >> ARCH_PAGE_SHIFT);

    while (vaddr != end)
    {
        /* TODO try to map with huge TLB, when flag & HUGEPAGE */
        struct rt_aspace_fault_msg msg;
        _do_page_fault(&msg, off, vaddr, varea->mem_obj, varea);

        if (rt_varea_map_with_msg(varea, &msg))
        {
            err = -RT_ENOMEM;
            break;
        }
        /**
         * It's hard to identify the mapping pattern on a customized handler
         * So we terminate the prefetch process on that case
         */
        if (msg.response.status == MM_FAULT_STATUS_OK_MAPPED)
            break;

        vaddr += msg.response.size;
        off += msg.response.size >> ARCH_PAGE_SHIFT;
    }

    return err;
}

static rt_err_t _expand_varea(rt_varea_t varea, void *new_va, rt_size_t size)
{