tree 7d28526f720ac5460dde965c57d2fea1ed6410b3
parent ce74117a1823431c86f5cb620fa852d21310feac
author Peter Hurley <peter@hurleysoftware.com> 1371302061 -0400
committer Greg Kroah-Hartman <gregkh@linuxfoundation.org> 1374622980 -0700

n_tty: Don't wrap input buffer indices at buffer size

Wrap read_buf indices (read_head, read_tail, canon_head) at
max representable value, instead of at the N_TTY_BUF_SIZE. This step
is necessary to allow lockless reads of these shared variables
(by updating the variables atomically).

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>