static inline unsigned long move_vma(struct vm_area_struct * vma,
unsigned long addr, unsigned long old_len, unsigned long new_len)
{
struct vm_area_struct * new_vma;
new_vma = kmem_cache_alloc(vm_area_cachep, SLAB_KERNEL);
if (new_vma) {
unsigned long new_addr = get_unmapped_area(addr, new_len);
if (new_addr && !move_page_tables(current->mm, new_addr, addr, old_len)) {
*new_vma = *vma;
new_vma->vm_start = new_addr;
new_vma->vm_end = new_addr+new_len;
new_vma->vm_offset = vma->vm_offset + (addr - vma->vm_start);
if (new_vma->vm_file)
new_vma->vm_file->f_count++;
if (new_vma->vm_ops && new_vma->vm_ops->open)
new_vma->vm_ops->open(new_vma);
insert_vm_struct(current->mm, new_vma);
merge_segments(current->mm, new_vma->vm_start, new_vma->vm_end);
do_munmap(addr, old_len);
current->mm->total_vm += new_len >> PAGE_SHIFT;
if (new_vma->vm_flags & VM_LOCKED) {
current->mm->locked_vm += new_len >> PAGE_SHIFT;
make_pages_present(new_vma->vm_start,
new_vma->vm_end);
}
return new_addr;
}
static inline unsigned long move_vma(struct vm_area_struct * vma,
unsigned long addr, unsigned long old_len, unsigned long new_len,
unsigned long new_addr)
{
struct mm_struct * mm = vma->vm_mm;
struct vm_area_struct * new_vma, * next, * prev;
int allocated_vma;
new_vma = NULL;
next = find_vma_prev(mm, new_addr, &prev);
if (next) {
if (prev && prev->vm_end == new_addr &&
can_vma_merge(prev, vma->vm_flags) && !vma->vm_file && !(vma->vm_flags & VM_SHARED)) {
spin_lock(&mm->page_table_lock);
prev->vm_end = new_addr + new_len;
spin_unlock(&mm->page_table_lock);
new_vma = prev;
if (next != prev->vm_next)
BUG();
if (prev->vm_end == next->vm_start && can_vma_merge(next, prev->vm_flags)) {
spin_lock(&mm->page_table_lock);
prev->vm_end = next->vm_end;
__vma_unlink(mm, next, prev);
spin_unlock(&mm->page_table_lock);
mm->map_count--;
kmem_cache_free(vm_area_cachep, next);
}
} else if (next->vm_start == new_addr + new_len &&
can_vma_merge(next, vma->vm_flags) && !vma->vm_file && !(vma->vm_flags & VM_SHARED)) {
spin_lock(&mm->page_table_lock);
next->vm_start = new_addr;
spin_unlock(&mm->page_table_lock);
new_vma = next;
}
} else {
prev = find_vma(mm, new_addr-1);
if (prev && prev->vm_end == new_addr &&
can_vma_merge(prev, vma->vm_flags) && !vma->vm_file && !(vma->vm_flags & VM_SHARED)) {
spin_lock(&mm->page_table_lock);
prev->vm_end = new_addr + new_len;
spin_unlock(&mm->page_table_lock);
new_vma = prev;
}
}
allocated_vma = 0;
if (!new_vma) {
new_vma = kmem_cache_alloc(vm_area_cachep, SLAB_KERNEL);
if (!new_vma)
goto out;
allocated_vma = 1;
}
if (!move_page_tables(current->mm, new_addr, addr, old_len)) {
unsigned long vm_locked = vma->vm_flags & VM_LOCKED;
if (allocated_vma) {
*new_vma = *vma;
new_vma->vm_start = new_addr;
new_vma->vm_end = new_addr+new_len;
new_vma->vm_pgoff += (addr-vma->vm_start) >> PAGE_SHIFT;
new_vma->vm_raend = 0;
if (new_vma->vm_file)
get_file(new_vma->vm_file);
if (new_vma->vm_ops && new_vma->vm_ops->open)
new_vma->vm_ops->open(new_vma);
insert_vm_struct(current->mm, new_vma);
}
/* XXX: possible errors masked, mapping might remain */
do_munmap(current->mm, addr, old_len);
current->mm->total_vm += new_len >> PAGE_SHIFT;
if (vm_locked) {
current->mm->locked_vm += new_len >> PAGE_SHIFT;
if (new_len > old_len)
make_pages_present(new_addr + old_len,
new_addr + new_len);
}
return new_addr;
}