diff options
Diffstat (limited to 'drivers/tty/pty.c')
-rw-r--r-- | drivers/tty/pty.c | 87 |
1 files changed, 52 insertions, 35 deletions
diff --git a/drivers/tty/pty.c b/drivers/tty/pty.c index 7c4447a5c0f4..a9d256d6e909 100644 --- a/drivers/tty/pty.c +++ b/drivers/tty/pty.c @@ -47,10 +47,13 @@ static void pty_close(struct tty_struct *tty, struct file *filp) set_bit(TTY_IO_ERROR, &tty->flags); wake_up_interruptible(&tty->read_wait); wake_up_interruptible(&tty->write_wait); + spin_lock_irq(&tty->ctrl_lock); tty->packet = 0; + spin_unlock_irq(&tty->ctrl_lock); /* Review - krefs on tty_link ?? */ if (!tty->link) return; + tty_flush_to_ldisc(tty->link); set_bit(TTY_OTHER_CLOSED, &tty->link->flags); wake_up_interruptible(&tty->link->read_wait); wake_up_interruptible(&tty->link->write_wait); @@ -64,9 +67,7 @@ static void pty_close(struct tty_struct *tty, struct file *filp) mutex_unlock(&devpts_mutex); } #endif - tty_unlock(tty); tty_vhangup(tty->link); - tty_lock(tty); } } @@ -178,21 +179,21 @@ static int pty_get_lock(struct tty_struct *tty, int __user *arg) /* Set the packet mode on a pty */ static int pty_set_pktmode(struct tty_struct *tty, int __user *arg) { - unsigned long flags; int pktmode; if (get_user(pktmode, arg)) return -EFAULT; - spin_lock_irqsave(&tty->ctrl_lock, flags); + spin_lock_irq(&tty->ctrl_lock); if (pktmode) { if (!tty->packet) { - tty->packet = 1; tty->link->ctrl_status = 0; + smp_mb(); + tty->packet = 1; } } else tty->packet = 0; - spin_unlock_irqrestore(&tty->ctrl_lock, flags); + spin_unlock_irq(&tty->ctrl_lock); return 0; } @@ -207,15 +208,12 @@ static int pty_get_pktmode(struct tty_struct *tty, int __user *arg) /* Send a signal to the slave */ static int pty_signal(struct tty_struct *tty, int sig) { - unsigned long flags; struct pid *pgrp; if (tty->link) { - spin_lock_irqsave(&tty->link->ctrl_lock, flags); - pgrp = get_pid(tty->link->pgrp); - spin_unlock_irqrestore(&tty->link->ctrl_lock, flags); - - kill_pgrp(pgrp, sig, 1); + pgrp = tty_get_pgrp(tty->link); + if (pgrp) + kill_pgrp(pgrp, sig, 1); put_pid(pgrp); } return 0; @@ -224,16 +222,15 @@ 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; - unsigned long flags; if (!to) return; /* tty_buffer_flush(to); FIXME */ if (to->packet) { - spin_lock_irqsave(&tty->ctrl_lock, flags); + spin_lock_irq(&tty->ctrl_lock); tty->ctrl_status |= TIOCPKT_FLUSHWRITE; wake_up_interruptible(&to->read_wait); - spin_unlock_irqrestore(&tty->ctrl_lock, flags); + spin_unlock_irq(&tty->ctrl_lock); } } @@ -262,6 +259,32 @@ out: static void pty_set_termios(struct tty_struct *tty, struct ktermios *old_termios) { + /* See if packet mode change of state. */ + if (tty->link && tty->link->packet) { + int extproc = (old_termios->c_lflag & EXTPROC) | + (tty->termios.c_lflag & EXTPROC); + int old_flow = ((old_termios->c_iflag & IXON) && + (old_termios->c_cc[VSTOP] == '\023') && + (old_termios->c_cc[VSTART] == '\021')); + int new_flow = (I_IXON(tty) && + STOP_CHAR(tty) == '\023' && + START_CHAR(tty) == '\021'); + if ((old_flow != new_flow) || extproc) { + spin_lock_irq(&tty->ctrl_lock); + if (old_flow != new_flow) { + tty->ctrl_status &= ~(TIOCPKT_DOSTOP | TIOCPKT_NOSTOP); + if (new_flow) + tty->ctrl_status |= TIOCPKT_DOSTOP; + else + tty->ctrl_status |= TIOCPKT_NOSTOP; + } + if (extproc) + tty->ctrl_status |= TIOCPKT_IOCTL; + spin_unlock_irq(&tty->ctrl_lock); + wake_up_interruptible(&tty->link->read_wait); + } + } + tty->termios.c_cflag &= ~(CSIZE | PARENB); tty->termios.c_cflag |= (CS8 | CREAD); } @@ -278,7 +301,6 @@ static void pty_set_termios(struct tty_struct *tty, static int pty_resize(struct tty_struct *tty, struct winsize *ws) { struct pid *pgrp, *rpgrp; - unsigned long flags; struct tty_struct *pty = tty->link; /* For a PTY we need to lock the tty side */ @@ -286,17 +308,9 @@ static int pty_resize(struct tty_struct *tty, struct winsize *ws) if (!memcmp(ws, &tty->winsize, sizeof(*ws))) goto done; - /* Get the PID values and reference them so we can - avoid holding the tty ctrl lock while sending signals. - We need to lock these individually however. */ - - spin_lock_irqsave(&tty->ctrl_lock, flags); - pgrp = get_pid(tty->pgrp); - spin_unlock_irqrestore(&tty->ctrl_lock, flags); - - spin_lock_irqsave(&pty->ctrl_lock, flags); - rpgrp = get_pid(pty->pgrp); - spin_unlock_irqrestore(&pty->ctrl_lock, flags); + /* Signal the foreground process group of both ptys */ + pgrp = tty_get_pgrp(tty); + rpgrp = tty_get_pgrp(pty); if (pgrp) kill_pgrp(pgrp, SIGWINCH, 1); @@ -327,26 +341,26 @@ static void pty_start(struct tty_struct *tty) { unsigned long flags; - spin_lock_irqsave(&tty->ctrl_lock, flags); if (tty->link && tty->link->packet) { + spin_lock_irqsave(&tty->ctrl_lock, flags); tty->ctrl_status &= ~TIOCPKT_STOP; tty->ctrl_status |= TIOCPKT_START; + spin_unlock_irqrestore(&tty->ctrl_lock, flags); wake_up_interruptible_poll(&tty->link->read_wait, POLLIN); } - spin_unlock_irqrestore(&tty->ctrl_lock, flags); } static void pty_stop(struct tty_struct *tty) { unsigned long flags; - spin_lock_irqsave(&tty->ctrl_lock, flags); if (tty->link && tty->link->packet) { + spin_lock_irqsave(&tty->ctrl_lock, flags); tty->ctrl_status &= ~TIOCPKT_START; tty->ctrl_status |= TIOCPKT_STOP; + spin_unlock_irqrestore(&tty->ctrl_lock, flags); wake_up_interruptible_poll(&tty->link->read_wait, POLLIN); } - spin_unlock_irqrestore(&tty->ctrl_lock, flags); } /** @@ -368,6 +382,10 @@ static int pty_common_install(struct tty_driver *driver, struct tty_struct *tty, int idx = tty->index; int retval = -ENOMEM; + /* Opening the slave first has always returned -EIO */ + if (driver->subtype != PTY_TYPE_MASTER) + return -EIO; + ports[0] = kmalloc(sizeof **ports, GFP_KERNEL); ports[1] = kmalloc(sizeof **ports, GFP_KERNEL); if (!ports[0] || !ports[1]) @@ -380,6 +398,8 @@ static int pty_common_install(struct tty_driver *driver, struct tty_struct *tty, if (!o_tty) goto err_put_module; + tty_set_lock_subclass(o_tty); + if (legacy) { /* We always use new tty termios data so we can do this the easy way .. */ @@ -404,8 +424,6 @@ static int pty_common_install(struct tty_driver *driver, struct tty_struct *tty, * Everything allocated ... set up the o_tty structure. */ tty_driver_kref_get(driver->other); - if (driver->subtype == PTY_TYPE_MASTER) - o_tty->count++; /* Establish the links in both directions */ tty->link = o_tty; o_tty->link = tty; @@ -417,6 +435,7 @@ static int pty_common_install(struct tty_driver *driver, struct tty_struct *tty, tty_driver_kref_get(driver); tty->count++; + o_tty->count++; return 0; err_free_termios: if (legacy) @@ -489,7 +508,6 @@ static const struct tty_operations master_pty_ops_bsd = { .flush_buffer = pty_flush_buffer, .chars_in_buffer = pty_chars_in_buffer, .unthrottle = pty_unthrottle, - .set_termios = pty_set_termios, .ioctl = pty_bsd_ioctl, .cleanup = pty_cleanup, .resize = pty_resize, @@ -666,7 +684,6 @@ static const struct tty_operations ptm_unix98_ops = { .flush_buffer = pty_flush_buffer, .chars_in_buffer = pty_chars_in_buffer, .unthrottle = pty_unthrottle, - .set_termios = pty_set_termios, .ioctl = pty_unix98_ioctl, .resize = pty_resize, .shutdown = pty_unix98_shutdown, |