-
-static struct page *syscall_nopage(struct vm_area_struct *vma,
- unsigned long adr, int *type)
-{
- struct page *p = virt_to_page(adr - vma->vm_start + syscall_page);
- get_page(p);
- return p;
-}
-
-/* Prevent VMA merging */
-static void syscall_vma_close(struct vm_area_struct *vma)
-{
-}
-
-static struct vm_operations_struct syscall_vm_ops = {
- .close = syscall_vma_close,
- .nopage = syscall_nopage,
-};
-
-/* Defined in vsyscall-sysenter.S */
-extern void SYSENTER_RETURN;
-
-/* Setup a VMA at program startup for the vsyscall page */
-int arch_setup_additional_pages(struct linux_binprm *bprm, int exstack,
- unsigned long start_code, unsigned long interp_map_address)
-{
- struct vm_area_struct *vma;
- struct mm_struct *mm = current->mm;
- unsigned long addr;
- int ret;
-
- down_write(&mm->mmap_sem);
- addr = get_unmapped_area_prot(NULL, 0, PAGE_SIZE, 0, 0, 1);
- if (IS_ERR_VALUE(addr)) {
- ret = addr;
- goto up_fail;
- }
-
- vma = kmem_cache_zalloc(vm_area_cachep, SLAB_KERNEL);
- if (!vma) {
- ret = -ENOMEM;
- goto up_fail;
- }
-
- vma->vm_start = addr;
- vma->vm_end = addr + PAGE_SIZE;
- /* MAYWRITE to allow gdb to COW and set breakpoints */
- vma->vm_flags = VM_READ|VM_EXEC|VM_MAYREAD|VM_MAYEXEC|VM_MAYWRITE;
- vma->vm_flags |= mm->def_flags;
- vma->vm_page_prot = protection_map[vma->vm_flags & 7];
- vma->vm_ops = &syscall_vm_ops;
- vma->vm_mm = mm;
-
- ret = insert_vm_struct(mm, vma);
- if (unlikely(ret)) {
- kmem_cache_free(vm_area_cachep, vma);
- goto up_fail;
- }
-
- current->mm->context.vdso = (void *)addr;
- current_thread_info()->sysenter_return =
- (void *)VDSO_SYM(&SYSENTER_RETURN);
- vx_vmpages_inc(mm);
-up_fail:
- up_write(&mm->mmap_sem);
- return ret;
-}
-
-const char *arch_vma_name(struct vm_area_struct *vma)
-{
- if (vma->vm_mm && vma->vm_start == (long)vma->vm_mm->context.vdso)
- return "[vdso]";
- return NULL;
-}
-
-struct vm_area_struct *get_gate_vma(struct task_struct *tsk)
-{
- return NULL;
-}
-
-int in_gate_area(struct task_struct *task, unsigned long addr)
-{
- return 0;
-}
-
-int in_gate_area_no_task(unsigned long addr)
-{
- return 0;
-}