From f6c8dbe6e50c6e5121d7b6644718207daa008221 Mon Sep 17 00:00:00 2001 From: Peter Hurley Date: Sat, 15 Jun 2013 07:28:28 -0400 Subject: n_tty: Encapsulate minimum_to_wake within N_TTY minimum_to_wake is unique to N_TTY processing, and belongs in per-ldisc data. Add the ldisc method, ldisc_ops::fasync(), to notify line disciplines when signal-driven I/O is enabled or disabled. When enabled for N_TTY (by fcntl(F_SETFL, O_ASYNC)), blocking reader/polls will be woken for any readable input. When disabled, blocking reader/polls are not woken until the read buffer is full. Canonical mode (L_ICANON(tty), n_tty_data::icanon) is not affected by the minimum_to_wake setting. Signed-off-by: Peter Hurley Signed-off-by: Greg Kroah-Hartman --- drivers/tty/tty_io.c | 17 +++++++++-------- 1 file changed, 9 insertions(+), 8 deletions(-) (limited to 'drivers/tty/tty_io.c') diff --git a/drivers/tty/tty_io.c b/drivers/tty/tty_io.c index 6464029e4860..bd88007fa6ea 100644 --- a/drivers/tty/tty_io.c +++ b/drivers/tty/tty_io.c @@ -2138,6 +2138,7 @@ static unsigned int tty_poll(struct file *filp, poll_table *wait) static int __tty_fasync(int fd, struct file *filp, int on) { struct tty_struct *tty = file_tty(filp); + struct tty_ldisc *ldisc; unsigned long flags; int retval = 0; @@ -2148,11 +2149,17 @@ static int __tty_fasync(int fd, struct file *filp, int on) if (retval <= 0) goto out; + ldisc = tty_ldisc_ref(tty); + if (ldisc) { + if (ldisc->ops->fasync) + ldisc->ops->fasync(tty, on); + tty_ldisc_deref(ldisc); + } + if (on) { enum pid_type type; struct pid *pid; - if (!waitqueue_active(&tty->read_wait)) - tty->minimum_to_wake = 1; + spin_lock_irqsave(&tty->ctrl_lock, flags); if (tty->pgrp) { pid = tty->pgrp; @@ -2165,13 +2172,7 @@ static int __tty_fasync(int fd, struct file *filp, int on) spin_unlock_irqrestore(&tty->ctrl_lock, flags); retval = __f_setown(filp, pid, type, 0); put_pid(pid); - if (retval) - goto out; - } else { - if (!tty->fasync && !waitqueue_active(&tty->read_wait)) - tty->minimum_to_wake = N_TTY_BUF_SIZE; } - retval = 0; out: return retval; } -- cgit v1.2.3 From 64e377dcd7d75c241d614458e9619d3445de44ef Mon Sep 17 00:00:00 2001 From: Peter Hurley Date: Sat, 15 Jun 2013 09:01:00 -0400 Subject: tty: Reset itty for other pty Commit 19ffd68f816878aed456d5e87697f43bd9e3bd2b ('pty: Remove redundant itty reset') introduced a regression whereby the other pty's linkage is not cleared on teardown. This triggers a false positive diagnostic in testing. Properly reset the itty linkage. Signed-off-by: Peter Hurley Cc: stable # 3.10 Signed-off-by: Greg Kroah-Hartman --- drivers/tty/tty_io.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'drivers/tty/tty_io.c') diff --git a/drivers/tty/tty_io.c b/drivers/tty/tty_io.c index bd88007fa6ea..366af832794b 100644 --- a/drivers/tty/tty_io.c +++ b/drivers/tty/tty_io.c @@ -1618,6 +1618,8 @@ static void release_tty(struct tty_struct *tty, int idx) tty_free_termios(tty); tty_driver_remove_tty(tty->driver, tty); tty->port->itty = NULL; + if (tty->link) + tty->link->port->itty = NULL; cancel_work_sync(&tty->port->buf.work); if (tty->link) -- cgit v1.2.3