ext4: use i_size_read in ext4_unaligned_aio()

We haven't taken i_mutex yet, so we need to use i_size_read().
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
Cc: stable@vger.kernel.org

fs/ext4/file.c

@@ -82,7 +82,7 @@ ext4_unaligned_aio(struct inode *inode, const struct iovec *iov,
 	size_t count = iov_length(iov, nr_segs);
 	loff_t final_size = pos + count;
 
-	if (pos >= inode->i_size)
+	if (pos >= i_size_read(inode))
 		return 0;
 
 	if ((pos & blockmask) || (final_size & blockmask))