blkdev_aio_read(): switch to generic_file_read_iter(), get rid of iov_shorten()

	struct file *file = iocb->ki_filp;

	struct file *file = iocb->ki_filp;

	struct inode *bd_inode = file->f_mapping->host;

	struct inode *bd_inode = file->f_mapping->host;

	loff_t size = i_size_read(bd_inode);

	loff_t size = i_size_read(bd_inode);

	size_t count = iocb->ki_nbytes;

	struct iov_iter to;

	iov_iter_init(&to, READ, iov, nr_segs, count);

	if (pos >= size)

	if (pos >= size)

		return 0;

		return 0;

	size -= pos;

	size -= pos;

	if (size < iocb->ki_nbytes)

	iov_iter_truncate(&to, size);

		nr_segs = iov_shorten((struct iovec *)iov, nr_segs, size);

	return generic_file_read_iter(iocb, &to);

	return generic_file_aio_read(iocb, iov, nr_segs, pos);

}

}

/*

/*