Merge branch 'next' into for-linus

Prepare first round of input updates for 3.20.

1 files changed, 89 insertions, 31 deletions

diff --git a/drivers/tty/pty.c b/drivers/tty/pty.c
index 9bbdb1de12e..a9d256d6e90 100644
--- a/drivers/tty/pty.c
+++ b/drivers/tty/pty.c
@@ -24,6 +24,7 @@
 #include <linux/devpts_fs.h>
 #include <linux/slab.h>
 #include <linux/mutex.h>
+#include <linux/poll.h>
 
 
 #ifdef CONFIG_UNIX98_PTYS
@@ -46,10 +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);
@@ -63,9 +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);
 	}
 }
 
@@ -177,21 +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;
 }
@@ -206,15 +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;
@@ -223,16 +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);
 	}
 }
 
@@ -261,6 +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);
 }
@@ -277,7 +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 */
@@ -285,17 +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);
@@ -313,6 +328,42 @@ done:
 }
 
 /**
+ *	pty_start - start() handler
+ *	pty_stop  - stop() handler
+ *	@tty: tty being flow-controlled
+ *
+ *	Propagates the TIOCPKT status to the master pty.
+ *
+ *	NB: only the master pty can be in packet mode so only the slave
+ *	    needs start()/stop() handlers
+ */
+static void pty_start(struct tty_struct *tty)
+{
+	unsigned long 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);
+	}
+}
+
+static void pty_stop(struct tty_struct *tty)
+{
+	unsigned long 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);
+	}
+}
+
+/**
  *	pty_common_install		-	set up the pty pair
  *	@driver: the pty driver
  *	@tty: the tty being instantiated
@@ -331,6 +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])
@@ -343,6 +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 .. */
@@ -367,8 +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;
@@ -380,6 +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)
@@ -452,7 +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,
@@ -471,6 +526,8 @@ static const struct tty_operations slave_pty_ops_bsd = {
 	.set_termios = pty_set_termios,
 	.cleanup = pty_cleanup,
 	.resize = pty_resize,
+	.start = pty_start,
+	.stop = pty_stop,
 	.remove = pty_remove
 };
 
@@ -627,7 +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,
@@ -646,6 +702,8 @@ static const struct tty_operations pty_unix98_ops = {
 	.chars_in_buffer = pty_chars_in_buffer,
 	.unthrottle = pty_unthrottle,
 	.set_termios = pty_set_termios,
+	.start = pty_start,
+	.stop = pty_stop,
 	.shutdown = pty_unix98_shutdown,
 	.cleanup = pty_cleanup,
 };