#include <klibc/string.h>
#include <lunaix/mm/pmm.h>
#include <lunaix/mm/vmm.h>
#include <lunaix/spike.h>
#include <lunaix/syslog.h>

#include <sys/cpu.h>
#include <sys/mm/mm_defs.h>

LOG_MODULE("VM")

void
vmm_init()
{
    // XXX: something here?
}

pte_t 
vmm_alloc_page(pte_t* ptep, pte_t pte)
{
    ptr_t pa = pmm_alloc_page(PP_FGPERSIST);
    if (!pa) {
        return null_pte;
    }

    pte = pte_setpaddr(pte, pa);
    pte = pte_mkloaded(pte);
    set_pte(ptep, pte);

    mount_page(PG_MOUNT_1, pa);
    memset((void*)PG_MOUNT_1, 0, LFT_SIZE);
    unmount_page(PG_MOUNT_1);

    cpu_flush_page((ptr_t)ptep);

    return pte;
}

int
vmm_set_mapping(ptr_t mnt, ptr_t va, ptr_t pa, pte_attr_t prot)
{
    assert(!va_offset(va));

    pte_t* ptep = mkptep_va(mnt, va);
    pte_t  pte  = mkpte(pa, prot);

    set_pte(ptep, pte);

    return 1;
}

ptr_t
vmm_del_mapping(ptr_t mnt, ptr_t va)
{
    assert(!va_offset(va));

    pte_t* ptep = mkptep_va(mnt, va);

    pte_t old = *ptep;

    set_pte(ptep, null_pte);

    return pte_paddr(old);
}

pte_t
vmm_tryptep(pte_t* ptep, size_t lvl_size)
{
    ptr_t va = ptep_va(ptep, lvl_size);
    pte_t* _ptep = mkl0tep(ptep);
    pte_t pte;

    if (pte_isnull(pte = *_ptep) || _ptep == ptep) 
        return pte;

#if LnT_ENABLED(1)
    _ptep = getl1tep(_ptep, va);
    if (_ptep == ptep || pte_isnull(pte = *_ptep)) 
        return pte;
#endif
#if LnT_ENABLED(2)
    _ptep = getl2tep(_ptep, va);
    if (_ptep == ptep || pte_isnull(pte = *_ptep)) 
        return pte;
#endif
#if LnT_ENABLED(3)
    _ptep = getl3tep(_ptep, va);
    if (_ptep == ptep || pte_isnull(pte = *_ptep)) 
        return pte;
#endif
    _ptep = getlftep(_ptep, va);
    return *_ptep;
}

ptr_t
vmm_v2pat(ptr_t mnt, ptr_t va)
{
    ptr_t  va_off = va_offset(va);
    pte_t* ptep   = mkptep_va(mnt, va);

    return pte_paddr(pte_at(ptep)) + va_off;
}

ptr_t
vms_mount(ptr_t mnt, ptr_t vms_root)
{
    assert(vms_root);

    pte_t* ptep = mkl0tep_va(VMS_SELF, mnt);
    set_pte(ptep, mkpte(vms_root, KERNEL_DATA));
    cpu_flush_page(mnt);
    return mnt;
}

ptr_t
vms_unmount(ptr_t mnt)
{
    pte_t* ptep = mkl0tep_va(VMS_SELF, mnt);
    set_pte(ptep, null_pte);
    cpu_flush_page(mnt);
    return mnt;
}


void
ptep_alloc_hierarchy(pte_t* ptep, ptr_t va, pte_attr_t prot)
{
    pte_t* _ptep;
    
    _ptep = mkl0tep(ptep);
    if (_ptep == ptep) {
        return;
    }

    _ptep = mkl1t(_ptep, va, prot);
    if (_ptep == ptep) {
        return;
    }

    _ptep = mkl2t(_ptep, va, prot);
    if (_ptep == ptep) {
        return;
    }

    _ptep = mkl3t(_ptep, va, prot);
    if (_ptep == ptep) {
        return;
    }

    _ptep = mklft(_ptep, va, prot);
    assert(_ptep == ptep);
}