/*
* lpage_destroy: deallocates a logical page. Releases any RAM or swap
* pages involved.
*
* Synchronization: Someone might be in the process of evicting the
* page if it's resident, so it might be pinned. So lock and pin
* together.
*
* We assume that lpages are not shared between address spaces and
* address spaces are not shared between threads.
*/
void
lpage_destroy(struct lpage *lp)
{
paddr_t pa;
KASSERT(lp != NULL);
lpage_lock_and_pin(lp);
pa = lp->lp_paddr & PAGE_FRAME;
if (pa != INVALID_PADDR) {
DEBUG(DB_VM, "lpage_destroy: freeing paddr 0x%x\n", pa);
lp->lp_paddr = INVALID_PADDR;
lpage_unlock(lp);
coremap_free(pa, false /* iskern */);
coremap_unpin(pa);
}
else {
lpage_unlock(lp);
}
if (lp->lp_swapaddr != INVALID_SWAPADDR) {
DEBUG(DB_VM, "lpage_destroy: freeing swap addr 0x%llx\n",
lp->lp_swapaddr);
swap_free(lp->lp_swapaddr);
}
spinlock_cleanup(&lp->lp_spinlock);
kfree(lp);
}
void
free_kpages(vaddr_t addr)
{
paddr_t pa = KVADDR_TO_PADDR(addr);
if (pa < start_addr) (void)addr; // dont do anything
// we have no access to these memory
else coremap_free(pa);
}
static
void
coremapthread(void *sm, unsigned long num)
{
struct semaphore *sem = sm;
uint32_t page;
uint32_t oldpage = 0;
uint32_t oldpage2 = 0;
int i;
for (i=0; i<NTRIES; i++) {
page = alloc_kpages(NPAGES);
if (page==0) {
if (sem) {
kprintf("thread %lu: alloc_kpages failed\n",
num);
V(sem);
return;
}
kprintf("alloc_kpages failed; test failed.\n");
return;
}
if (oldpage2) {
coremap_free(KVADDR_TO_PADDR(oldpage2), true /* iskern */);
}
oldpage2 = oldpage;
oldpage = page;
}
if (oldpage2) {
coremap_free(KVADDR_TO_PADDR(oldpage2), true /* iskern */);
}
if (oldpage) {
coremap_free(KVADDR_TO_PADDR(oldpage), true /* iskern */);
}
if (sem) {
V(sem);
}
}
/*
* free_kpages
*
* Free pages allocated with alloc_kpages.
* Synchronization: takes coremap_spinlock. Does not block.
*/
void
free_kpages(vaddr_t addr)
{
coremap_free(KVADDR_TO_PADDR(addr), true /* iskern */);
}
