void
as_activate(void)
{
struct addrspace *as;
as = proc_getas();
if (as == NULL) {
/*
* Kernel thread without an address space; leave the
* prior address space in place.
*/
return;
}
/*
* Write this.
*/
int i, spl;
spl = splhigh();
for (i=0; i<NUM_TLB; i++) {
tlb_write(TLBHI_INVALID(i), TLBLO_INVALID(), i);
}
splx(spl);
}
/*
* tlb_invalidate: marks a given tlb entry as invalid.
*
* Synchronization: assumes we hold coremap_spinlock. Does not block.
*/
static
void
tlb_invalidate(int tlbix)
{
uint32_t elo, ehi;
paddr_t pa;
unsigned cmix;
KASSERT(spinlock_do_i_hold(&coremap_spinlock));
tlb_read(&ehi, &elo, tlbix);
if (elo & TLBLO_VALID) {
pa = elo & TLBLO_PPAGE;
cmix = PADDR_TO_COREMAP(pa);
KASSERT(cmix < num_coremap_entries);
KASSERT(coremap[cmix].cm_tlbix == tlbix);
KASSERT(coremap[cmix].cm_cpunum == curcpu->c_number);
coremap[cmix].cm_tlbix = -1;
coremap[cmix].cm_cpunum = 0;
DEBUG(DB_TLB, "... pa 0x%05lx --> tlb --\n",
(unsigned long) COREMAP_TO_PADDR(cmix));
}
tlb_write(TLBHI_INVALID(tlbix), TLBLO_INVALID(), tlbix);
DEBUG(DB_TLB, "... pa ------- <-- tlb %d\n", tlbix);
}
void
as_activate(struct addrspace *as)
{
/*
* Write this.
*/
//dumbvm implementation to get kernel compiling initially:
int i, spl;
//to check if address space is different from old one
static struct addrspace *old_as = NULL;
(void)as;
spl = splhigh();
#if OPT_A3
if (old_as != as) {
for (i=0; i<NUM_TLB; i++) {
TLB_Write(TLBHI_INVALID(i), TLBLO_INVALID(), i);
}
vmstats_inc(3);
}
#else
for (i=0; i<NUM_TLB; i++) {
TLB_Write(TLBHI_INVALID(i), TLBLO_INVALID(), i);
}
#endif
//make the one passed in as old
old_as = as;
splx(spl);
//end dumbvm implementation. add/fix later
(void)as; // suppress warning until code gets written
}
void
tlb_invalidate(int slot)
{
int spl = splhigh();
u_int32_t elo,ehi;
TLB_Read(&ehi,&elo,slot);
if (elo & TLBLO_VALID) TLB_Write(TLBHI_INVALID(slot),TLBLO_INVALID(),slot);
splx(spl);
}
void
vm_tlbshootdown_all(void)
{
//panic("dumbvm tried to do tlb shootdown?!\n");
int i;
for (i=0; i<NUM_TLB; i++) {
tlb_write(TLBHI_INVALID(i), TLBLO_INVALID(), i);
}
}
void vm_flushtlb(void) {
int i;
//int spl = splhigh(); // lock TLB while we mess with it
spinlock_acquire(&tlb_lock);
for (i=0; i<NUM_TLB;i++) {
tlb_write(TLBHI_INVALID(i),TLBLO_INVALID(),i); // invalidate all TLB entries
}
spinlock_release(&tlb_lock);
//splx(spl);
}
void
vm_tlbflush(vaddr_t target)
{
int spl;
int index;
spl = splhigh();
index = tlb_probe(target & PAGE_FRAME, 0);
if (index >=0)
tlb_write(TLBHI_INVALID(index), TLBLO_INVALID(), index);
splx(spl);
}
void
vm_tlbflush_all(void)
{
int i, spl;
spl = splhigh();
for (i=0; i<NUM_TLB; i++) {
tlb_write(TLBHI_INVALID(i), TLBLO_INVALID(), i);
}
splx(spl);
}
void freePage(struct page* page) {
if(page->pt_state == PT_STATE_MAPPED) {
coremap_freeuserpages(page->pt_pagebase * PAGE_SIZE);
int spl = splhigh();
int tlbpos = tlb_probe(page->pt_pagebase * PAGE_SIZE, 0);
if (tlbpos >= 0) {
tlb_write(TLBHI_INVALID(tlbpos), TLBLO_INVALID(), tlbpos);
}
splx(spl);
} else if(page->pt_state == PT_STATE_MAPPED) {
swapfree(page);
}
}
void vm_tlbshootdown_all(void)
{
int i, spl;
/* Disable interrupts on this CPU while frobbing the TLB. */
spl = splhigh();
for (i=0; i<NUM_TLB; i++) {
tlb_write(TLBHI_INVALID(i), TLBLO_INVALID(), i);
}
splx(spl);
}
/*Shoot down a TLB entry based on given virtual address*/
void
tlb_shootdown_page_table_entry(vaddr_t va) {
int i;
uint32_t ehi, elo;
KASSERT((va & PAGE_FRAME ) == va); //assert that va is a valid virtual address
spinlock_acquire(&stealmem_lock);
for(i=0; i < NUM_TLB; i++) {
tlb_read(&ehi, &elo, i);
if (ehi == va) {
tlb_write(TLBHI_INVALID(i), TLBLO_INVALID(), i);
break;
}
}
spinlock_release(&stealmem_lock);
}
/* TLB shootdown handling called from interprocessor_interrupt */
void vm_tlbshootdown_all(void)
{
int spl;
/* Disable interrupts on this CPU while frobbing the TLB. */
bool lock = get_coremap_spinlock();
spl = splhigh();
/* Shoot down all the TLB entries. */
for (int i = 0; i < NUM_TLB; i++) {
tlb_write(TLBHI_INVALID(i), TLBLO_INVALID(), i);
}
splx(spl);
release_coremap_spinlock(lock);
return;
}
void vm_tlbshootdown(const struct tlbshootdown *ts)
{
int i, spl;
/* Disable interrupts on this CPU while frobbing the TLB. */
spl = splhigh();
uint32_t ehi, elo;
for (i=0; i<NUM_TLB; i++) {
tlb_read(&ehi, &elo, i);
if (ehi == ts->ts_vaddr)
{
tlb_write(TLBHI_INVALID(i), TLBLO_INVALID(), i);
break ;
}
}
splx(spl);
}
static void swaponepagein(int idx, struct addrspace* as) {
(void) as;
// 3. clear their tlb entries if present TODO
cm_setEntryDirtyState(COREMAP(idx),true);
struct page* pg = findPageFromCoreMap(COREMAP(idx), idx);
int spl = splhigh();
int tlbpos = tlb_probe(pg->pt_pagebase * PAGE_SIZE, 0);
if (tlbpos >= 0) {
tlb_write(TLBHI_INVALID(tlbpos), TLBLO_INVALID(), tlbpos);
} else {
//kprintf("was not on tlb\n");
}
splx(spl);
int swapPageindex = getOneSwapPage();
kprintf("Swap in :\tswap= %x,\tpage=%x \n",swapPageindex,pg->pt_virtbase);
//kprintf("Swap in page Vaddr = %x\n", pg->pt_virtbase);
struct iovec iov;
struct uio kuio;
iov.iov_kbase = (void*) PADDR_TO_KVADDR(cm_getEntryPaddr(idx));
iov.iov_len = PAGE_SIZE; // length of the memory space
kuio.uio_iov = &iov;
kuio.uio_iovcnt = 1;
kuio.uio_resid = PAGE_SIZE; // amount to write to the file
kuio.uio_space = NULL;
kuio.uio_offset = swap_map[swapPageindex].se_paddr * PAGE_SIZE;
kuio.uio_segflg = UIO_SYSSPACE;
kuio.uio_rw = UIO_WRITE;
//kprintf("before write \n");
// 4. write them to disk
spinlock_release(&coremap_lock);
int result = VOP_WRITE(swap_vnode, &kuio);
spinlock_acquire(&coremap_lock);
if (result) {
// release lock on the vnode
panic("WRITE FAILED!\n");
return;
}
cm_setEntryDirtyState(COREMAP(idx),false);
//kprintf("write complete\n");
pg->pt_state = PT_STATE_SWAPPED;
pg->pt_pagebase = swap_map[swapPageindex].se_paddr;
}
void vm_tlbshootdown(const struct tlbshootdown *ts)
{
//(void)ts;
int tlb_entry, spl;
/* Disable interrupts on this CPU while frobbing the TLB. */
bool lock = get_coremap_spinlock();
spl = splhigh();
// Probe TLB so see if particular VA is present.
tlb_entry = tlb_probe(VA_TO_VPF(ts->ts_vaddr), 0);
if(tlb_entry < 0) {
// No entry found, so shoot down succeeded
splx(spl);
return;
}
// Invalidate the particular TLB entry
tlb_write(TLBHI_INVALID(tlb_entry), TLBLO_INVALID(), tlb_entry);
splx(spl);
release_coremap_spinlock(lock);
}
void *
sys_sbrk(intptr_t amount, int *err){
vaddr_t retval = curproc->p_addrspace->heap_end;
if (amount < 0 && amount <= -4096*1024*256) {
*err = EINVAL;
return (void *)-1;
}
if (curproc->p_addrspace->heap_end + amount < curproc->p_addrspace->heap_start) {
*err = EINVAL;
return (void *)-1;
}
if (curproc->p_addrspace->heap_start + amount >= USERSTACK - 1024 * PAGE_SIZE) {
*err = ENOMEM;
return (void *)-1;
}
/* Align in multiples of 4 */
if (amount % 4 != 0) {
*err = EINVAL;
return (void *)-1;
}
int num_pages = (amount < 0) ? (amount * -1)/PAGE_SIZE : amount/PAGE_SIZE;
if (amount % PAGE_SIZE != 0)
num_pages++;
struct page_table *proc_pg_table = curproc->p_addrspace->page_table_entry;
struct page_table *prev_proc_pg_table;
struct page_table *free_proc_pg_table;
if(amount < 0) {
for (int i = 1; i <= num_pages; i++) {
// Page Table removal loop through the page table and remove entries correspondingly.
proc_pg_table = curproc->p_addrspace->page_table_entry;
prev_proc_pg_table = proc_pg_table;
while(proc_pg_table != NULL) {
if (proc_pg_table->vpn < USERSTACK - 1024 * PAGE_SIZE &&
proc_pg_table->vpn >= (curproc->p_addrspace->heap_end + amount)) {
prev_proc_pg_table->next = proc_pg_table->next;
free_proc_pg_table = proc_pg_table;
kfree((void *)PADDR_TO_KVADDR(free_proc_pg_table->ppn));
kfree(free_proc_pg_table);
break;
}
prev_proc_pg_table = proc_pg_table;
proc_pg_table = proc_pg_table->next;
}
}
// TLB cleanup code
int spl;
spl = splhigh();
for (int i=0; i < NUM_TLB; i++) {
tlb_write(TLBHI_INVALID(i), TLBLO_INVALID(), i);
}
splx(spl);
}
curproc->p_addrspace->heap_end += amount;
if (amount < 0)
as_activate();
return (void *)retval;
}