-int kvm_get_user_page_io(struct task_struct *tsk, struct mm_struct *mm,
- unsigned long addr, bool write_fault,
- struct page **pagep)
-{
- int npages;
- int locked = 1;
- int flags = FOLL_TOUCH | FOLL_HWPOISON |
- (pagep ? FOLL_GET : 0) |
- (write_fault ? FOLL_WRITE : 0);
-
- /*
- * If retrying the fault, we get here *not* having allowed the filemap
- * to wait on the page lock. We should now allow waiting on the IO with
- * the mmap semaphore released.
- */
- down_read(&mm->mmap_sem);
- npages = __get_user_pages(tsk, mm, addr, 1, flags, pagep, NULL,
- &locked);
- if (!locked) {
- VM_BUG_ON(npages);
-
- if (!pagep)
- return 0;
-
- /*
- * The previous call has now waited on the IO. Now we can
- * retry and complete. Pass TRIED to ensure we do not re
- * schedule async IO (see e.g. filemap_fault).
- */
- down_read(&mm->mmap_sem);
- npages = __get_user_pages(tsk, mm, addr, 1, flags | FOLL_TRIED,
- pagep, NULL, NULL);
- }
- up_read(&mm->mmap_sem);
- return npages;
-}
-