void X86Memory::releaseAll(X86Process *p)
{
/* Map page tables. */
mapRemote(p, 0x0);
/* Mark all our physical pages free. */
for (Size i = 0; i < 1024; i++)
{
/* May we release these physical pages? */
if ((remPageDir[i] & PAGE_PRESENT) && !(remPageDir[i] & PAGE_PINNED))
{
/* Repoint page table. */
remPageTab = PAGETABADDR_FROM(i * PAGESIZE * 1024,
PAGETABFROM_REMOTE);
/* Scan page table. */
for (Size j = 0; j < 1024; j++)
{
if (remPageTab[j] & PAGE_PRESENT && !(remPageTab[j] & PAGE_PINNED))
{
memory->releasePhysical(remPageTab[j]);
}
}
}
}
}
Address X86Memory::lookupVirtual(X86Process *p, Address vaddr)
{
Address ret = ZERO;
/* Map remote page tables. */
mapRemote(p, vaddr);
/* Lookup the address, if mapped. */
if (remPageDir[DIRENTRY(vaddr)] & PAGE_PRESENT &&
remPageTab[TABENTRY(vaddr)] & PAGE_PRESENT)
{
ret = remPageTab[TABENTRY(vaddr)];
}
return ret;
}
bool X86Memory::access(X86Process *p, Address vaddr, Size sz, ulong prot)
{
Size bytes = 0;
Address vfrom = vaddr;
/* Map remote pages. */
mapRemote(p, vaddr);
/* Verify protection bits. */
while (bytes < sz &&
remPageDir[DIRENTRY(vaddr)] & prot &&
remPageTab[TABENTRY(vaddr)] & prot)
{
vaddr += PAGESIZE;
bytes += ((vfrom & PAGEMASK) + PAGESIZE) - vfrom;
vfrom = vaddr & PAGEMASK;
remPageTab = PAGETABADDR_FROM(vaddr, PAGETABFROM_REMOTE);
}
/* Do we have a match? */
return (bytes >= sz);
}
Address X86Memory::mapVirtual(X86Process *p, Address paddr,
Address vaddr, ulong prot)
{
/* Map remote pages. */
mapRemote(p, vaddr);
/* Virtual address specified? */
if (vaddr == ZERO)
{
vaddr = findFree(PAGETABFROM_REMOTE, remPageDir);
}
/* Repoint to the correct (remote) page table. */
remPageTab = PAGETABADDR_FROM(vaddr, PAGETABFROM_REMOTE);
/* Does the remote process have the page table in memory? */
if (!(remPageDir[DIRENTRY(vaddr)] & PAGE_PRESENT))
{
/* Nope, allocate a page table first. */
Address newPageTab = memory->allocatePhysical(PAGESIZE);
newPageTab |= PAGE_PRESENT | PAGE_RW | prot;
/* Map the new page table into remote memory. */
remPageDir[DIRENTRY(vaddr)] = newPageTab;
/* Update caches. */
tlb_flush(remPageTab);
/* Zero the new page. */
memset(remPageTab, 0, PAGESIZE);
}
/* Map physical address to remote virtual address. */
remPageTab[TABENTRY(vaddr)] = (paddr & PAGEMASK) | prot;
tlb_flush(vaddr);
/* Success. */
return (Address) vaddr;
}
