// mm_destroy - free mm and mm internal fields
void
mm_destroy(struct mm_struct *mm) {
if (mm->mmap_tree != NULL) {
rb_tree_destroy(mm->mmap_tree);
}
while (!list_empty(&(mm->mmap_list))) {
list_entry_t *le = list_next(&(mm->mmap_list));
list_del(le);
vma_destroy(le2vma(le, list_link));
}
kfree(mm);
}
// mm_destroy - free mm and mm internal fields
void
mm_destroy(struct mm_struct *mm) {
assert(mm_count(mm) == 0);
if (mm->mmap_tree != NULL) {
rb_tree_destroy(mm->mmap_tree);
}
list_entry_t *list = &(mm->mmap_list), *le;
while ((le = list_next(list)) != list) {
list_del(le);
vma_destroy(le2vma(le, list_link));
}
kfree(mm);
}
int
mm_unmap(struct mm_struct *mm, uintptr_t addr, size_t len) {
uintptr_t start = ROUNDDOWN(addr, PGSIZE), end = ROUNDUP(addr + len, PGSIZE);
if (!USER_ACCESS(start, end)) {
return -E_INVAL;
}
assert(mm != NULL);
struct vma_struct *vma;
if ((vma = find_vma(mm, start)) == NULL || end <= vma->vm_start) {
return 0;
}
if (vma->vm_start < start && end < vma->vm_end) {
struct vma_struct *nvma;
if ((nvma = vma_create(vma->vm_start, start, vma->vm_flags)) == NULL) {
return -E_NO_MEM;
}
vma_resize(vma, end, vma->vm_end);
insert_vma_struct(mm, nvma);
unmap_range(mm->pgdir, start, end);
return 0;
}
list_entry_t free_list, *le;
list_init(&free_list);
while (vma->vm_start < end) {
le = list_next(&(vma->list_link));
remove_vma_struct(mm, vma);
list_add(&free_list, &(vma->list_link));
if (le == &(mm->mmap_list)) {
break;
}
vma = le2vma(le, list_link);
}
le = list_next(&free_list);
while (le != &free_list) {
vma = le2vma(le, list_link);
le = list_next(le);
uintptr_t un_start, un_end;
if (vma->vm_start < start) {
un_start = start, un_end = vma->vm_end;
vma_resize(vma, vma->vm_start, un_start);
insert_vma_struct(mm, vma);
}
else {
un_start = vma->vm_start, un_end = vma->vm_end;
if (end < un_end) {
un_end = end;
vma_resize(vma, un_end, vma->vm_end);
insert_vma_struct(mm, vma);
}
else {
vma_destroy(vma);
}
}
unmap_range(mm->pgdir, un_start, un_end);
}
return 0;
}
static int dreg_remove (dreg_entry *r)
{
vma_t *vma;
vma = vma_search (DREG_BEGIN (r));
if (vma == NULL) /* no such region in database */
return -1;
while (vma != &vma_list && vma->start <= DREG_END (r))
{
remove_entry (vma, r);
if (vma->list == NULL)
{
vma_t *next = vma->next;
vma_remove (vma);
vma->prev->next = vma->next;
vma->next->prev = vma->prev;
vma_destroy (vma);
vma = next;
}
else
{
int merged;
do {
merged = 0;
if (vma->start == vma->prev->end + 1 &&
compare_lists (vma, vma->prev))
{
vma_t *t = vma;
vma = vma->prev;
vma->end = t->end;
vma->next = t->next;
vma->next->prev = vma;
vma_remove (t);
vma_destroy (t);
merged = 1;
}
if (vma->end + 1 == vma->next->start &&
compare_lists (vma, vma->next))
{
vma_t *t = vma->next;
vma->end = t->end;
vma->next = t->next;
vma->next->prev = vma;
vma_remove (t);
vma_destroy (t);
merged = 1;
}
} while (merged);
vma = vma->next;
}
}
return 0;
}
