Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net

[firefly-linux-kernel-4.4.55.git] / drivers / tty / pty.c

diff --git a/drivers/tty/pty.c b/drivers/tty/pty.c
index a9d256d6e909c1aecfc854732694d608256aeb15..e72ee629cead1b0af93c54b96395cbfc98b69975 100644 (file)
--- a/drivers/tty/pty.c
+++ b/drivers/tty/pty.c
@@ -87,19 +87,6 @@ static void pty_unthrottle(struct tty_struct *tty)
        set_bit(TTY_THROTTLED, &tty->flags);
 }
 
-/**
- *     pty_space       -       report space left for writing
- *     @to: tty we are writing into
- *
- *     Limit the buffer space used by ptys to 8k.
- */
-
-static int pty_space(struct tty_struct *to)
-{
-       int n = tty_buffer_space_avail(to->port);
-       return min(n, 8192);
-}
-
 /**
  *     pty_write               -       write to a pty
  *     @tty: the tty we write from
@@ -141,7 +128,7 @@ static int pty_write_room(struct tty_struct *tty)
 {
        if (tty->stopped)
                return 0;
-       return pty_space(tty->link);
+       return tty_buffer_space_avail(tty->link->port);
 }
 
 /**
@@ -210,6 +197,9 @@ static int pty_signal(struct tty_struct *tty, int sig)
 {
        struct pid *pgrp;
 
+       if (sig != SIGINT && sig != SIGQUIT && sig != SIGTSTP)
+               return -EINVAL;
+
        if (tty->link) {
                pgrp = tty_get_pgrp(tty->link);
                if (pgrp)
@@ -222,10 +212,16 @@ static int pty_signal(struct tty_struct *tty, int sig)
 static void pty_flush_buffer(struct tty_struct *tty)
 {
        struct tty_struct *to = tty->link;
+       struct tty_ldisc *ld;
 
        if (!to)
                return;
-       /* tty_buffer_flush(to); FIXME */
+
+       ld = tty_ldisc_ref(to);
+       tty_buffer_flush(to, ld);
+       if (ld)
+               tty_ldisc_deref(ld);
+
        if (to->packet) {
                spin_lock_irq(&tty->ctrl_lock);
                tty->ctrl_status |= TIOCPKT_FLUSHWRITE;
@@ -399,6 +395,7 @@ static int pty_common_install(struct tty_driver *driver, struct tty_struct *tty,
                goto err_put_module;
 
        tty_set_lock_subclass(o_tty);
+       lockdep_set_subclass(&o_tty->termios_rwsem, TTY_LOCK_SLAVE);
 
        if (legacy) {
                /* We always use new tty termios data so we can do this
@@ -429,10 +426,14 @@ static int pty_common_install(struct tty_driver *driver, struct tty_struct *tty,
        o_tty->link = tty;
        tty_port_init(ports[0]);
        tty_port_init(ports[1]);
+       tty_buffer_set_limit(ports[0], 8192);
+       tty_buffer_set_limit(ports[1], 8192);
        o_tty->port = ports[0];
        tty->port = ports[1];
        o_tty->port->itty = o_tty;
 
+       tty_buffer_set_lock_subclass(o_tty->port);
+
        tty_driver_kref_get(driver);
        tty->count++;
        o_tty->count++;