Commit c2b0fb9f authored by Jiri Slaby (SUSE)'s avatar Jiri Slaby (SUSE) Committed by Greg Kroah-Hartman
Browse files

tty: n_tty: invert the condition in copy_from_read_buf() 



Make "no numbers available" a fast quit from the function. And do the
heavy work outside the 'if'. This makes the code more understandable and
conforming to the common kernel coding style.

Signed-off-by: default avatar"Jiri Slaby (SUSE)" <jirislaby@kernel.org>
Reviewed-by: default avatarIlpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20230919085156.1578-5-jirislaby@kernel.org


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 72369f2d

drivers/tty/n_tty.c

+20 −18
Original line number Diff line number Diff line
@@ -1966,25 +1966,27 @@ static bool copy_from_read_buf(const struct tty_struct *tty, u8 **kbp, 
	size_t tail = MASK(ldata->read_tail);



	n = min3(head - ldata->read_tail, N_TTY_BUF_SIZE - tail, *nr);

	if (n) {

	if (!n)

		return false;



	u8 *from = read_buf_addr(ldata, tail);

	memcpy(*kbp, from, n);

	is_eof = n == 1 && *from == EOF_CHAR(tty);

	tty_audit_add_data(tty, from, n);

	zero_buffer(tty, from, n);

	smp_store_release(&ldata->read_tail, ldata->read_tail + n);



	/* Turn single EOF into zero-length read */

	if (L_EXTPROC(tty) && ldata->icanon && is_eof &&

		    (head == ldata->read_tail))

	    head == ldata->read_tail)

		return false;



	*kbp += n;

	*nr -= n;



	/* If we have more to copy, let the caller know */

	return head != ldata->read_tail;

}

	return false;

}



/**

 * canon_copy_from_read_buf	-	copy read data in canonical mode