The bug was introduced by 
01f2705daf5a36208e69d7cf95db9c330f843af6.
It misses to convert the first argument, it should be "new_page".
This became a cause of fatfs corruption.
Cc: Nate Diller <nate.diller@gmail.com>
Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 
                                                PAGE_CACHE_SIZE, get_block);
                if (status)
                        goto out_unmap;
-               zero_user_page(page, zerofrom, PAGE_CACHE_SIZE - zerofrom,
+               zero_user_page(new_page, zerofrom, PAGE_CACHE_SIZE - zerofrom,
                                KM_USER0);
                generic_commit_write(NULL, new_page, zerofrom, PAGE_CACHE_SIZE);
                unlock_page(new_page);