void Multiboot_FreeModules(const int ModuleCount, tBootModule *Modules)
{
for( int i = 0; i < ModuleCount; i ++ )
{
Uint ofs = Modules[i].PBase % PAGE_SIZE;
Uint nPages = (Modules[i].Size+ofs+PAGE_SIZE-1) / PAGE_SIZE;
MM_UnmapHWPages(Modules[i].Base, nPages);
MM_UnmapHWPages(Modules[i].ArgString, 2);
// TODO: handle previous freeing of this page
for( int pg = 0; pg < nPages; pg ++ )
MM_DerefPhys( Modules[i].PBase + pg*PAGE_SIZE );
}
free(Modules);
}
/**
* \brief Clone a page from an entry
* \param Ent Pointer to the entry in the PML4/PDP/PD/PT
* \param NextLevel Pointer to contents of the entry
* \param Addr Dest address
* \note Used in COW
*/
void MM_int_ClonePageEnt( Uint64 *Ent, void *NextLevel, tVAddr Addr, int bTable )
{
tPAddr curpage = *Ent & PADDR_MASK;
int bCopied = 0;
if( MM_GetRefCount( curpage ) <= 0 ) {
Log_KernelPanic("MMVirt", "Page %P still marked COW, but unreferenced", curpage);
}
if( MM_GetRefCount( curpage ) == 1 )
{
*Ent &= ~PF_COW;
*Ent |= PF_PRESENT|PF_WRITE;
#if TRACE_COW
Log_Debug("MMVirt", "COW ent at %p (%p) only %P", Ent, NextLevel, curpage);
#endif
}
else
{
void *tmp;
tPAddr paddr;
if( !(paddr = MM_AllocPhys()) ) {
Threads_SegFault(Addr);
return ;
}
ASSERT(paddr != curpage);
tmp = MM_MapTemp(paddr);
memcpy( tmp, NextLevel, 0x1000 );
MM_FreeTemp( tmp );
#if TRACE_COW
Log_Debug("MMVirt", "COW ent at %p (%p) from %P to %P", Ent, NextLevel, curpage, paddr);
#endif
MM_DerefPhys( curpage );
*Ent &= PF_USER;
*Ent |= paddr|PF_PRESENT|PF_WRITE;
bCopied = 1;
}
INVLPG( (tVAddr)NextLevel );
// Mark COW on contents if it's a PDPT, Dir or Table
if(bTable)
{
Uint64 *dp = NextLevel;
int i;
for( i = 0; i < 512; i ++ )
{
if( !(dp[i] & PF_PRESENT) )
continue;
if( bCopied )
MM_RefPhys( dp[i] & PADDR_MASK );
if( dp[i] & PF_WRITE ) {
dp[i] &= ~PF_WRITE;
dp[i] |= PF_COW;
}
}
}
}
