1 files changed, 109 insertions, 41 deletions

diff --git a/drivers/char/tty_io.c b/drivers/char/tty_io.c
index 389da364e6b6..75d2a46e106f 100644
--- a/drivers/char/tty_io.c
+++ b/drivers/char/tty_io.c
@@ -141,8 +141,6 @@ static DECLARE_MUTEX(allocated_ptys_lock);
 static int ptmx_open(struct inode *, struct file *);
 #endif
 
-extern void disable_early_printk(void);
-
 static void initialize_tty_struct(struct tty_struct *tty);
 
 static ssize_t tty_read(struct file *, char __user *, size_t, loff_t *);
@@ -153,10 +151,16 @@ static int tty_open(struct inode *, struct file *);
 static int tty_release(struct inode *, struct file *);
 int tty_ioctl(struct inode * inode, struct file * file,
 	      unsigned int cmd, unsigned long arg);
+#ifdef CONFIG_COMPAT
+static long tty_compat_ioctl(struct file * file, unsigned int cmd,
+				unsigned long arg);
+#else
+#define tty_compat_ioctl NULL
+#endif
 static int tty_fasync(int fd, struct file * filp, int on);
 static void release_tty(struct tty_struct *tty, int idx);
-static struct pid *__proc_set_tty(struct task_struct *tsk,
-				struct tty_struct *tty);
+static void __proc_set_tty(struct task_struct *tsk, struct tty_struct *tty);
+static void proc_set_tty(struct task_struct *tsk, struct tty_struct *tty);
 
 /**
  *	alloc_tty_struct	-	allocate a tty object
@@ -365,6 +369,29 @@ static void tty_buffer_free(struct tty_struct *tty, struct tty_buffer *b)
 }
 
 /**
+ *	tty_buffer_flush		-	flush full tty buffers
+ *	@tty: tty to flush
+ *
+ *	flush all the buffers containing receive data
+ *
+ *	Locking: none
+ */
+
+static void tty_buffer_flush(struct tty_struct *tty)
+{
+	struct tty_buffer *thead;
+	unsigned long flags;
+
+	spin_lock_irqsave(&tty->buf.lock, flags);
+	while((thead = tty->buf.head) != NULL) {
+		tty->buf.head = thead->next;
+		tty_buffer_free(tty, thead);
+	}
+	tty->buf.tail = NULL;
+	spin_unlock_irqrestore(&tty->buf.lock, flags);
+}
+
+/**
  *	tty_buffer_find		-	find a free tty buffer
  *	@tty: tty owning the buffer
  *	@size: characters wanted
@@ -936,13 +963,6 @@ restart:
 		return -EINVAL;
 
 	/*
-	 *	No more input please, we are switching. The new ldisc
-	 *	will update this value in the ldisc open function
-	 */
-
-	tty->receive_room = 0;
-
-	/*
 	 *	Problem: What do we do if this blocks ?
 	 */
 
@@ -953,6 +973,13 @@ restart:
 		return 0;
 	}
 
+	/*
+	 *	No more input please, we are switching. The new ldisc
+	 *	will update this value in the ldisc open function
+	 */
+
+	tty->receive_room = 0;
+
 	o_ldisc = tty->ldisc;
 	o_tty = tty->link;
 
@@ -1145,8 +1172,8 @@ static unsigned int hung_up_tty_poll(struct file * filp, poll_table * wait)
 	return POLLIN | POLLOUT | POLLERR | POLLHUP | POLLRDNORM | POLLWRNORM;
 }
 
-static int hung_up_tty_ioctl(struct inode * inode, struct file * file,
-			     unsigned int cmd, unsigned long arg)
+static long hung_up_tty_ioctl(struct file * file,
+			      unsigned int cmd, unsigned long arg)
 {
 	return cmd == TIOCSPGRP ? -ENOTTY : -EIO;
 }
@@ -1157,6 +1184,7 @@ static const struct file_operations tty_fops = {
 	.write		= tty_write,
 	.poll		= tty_poll,
 	.ioctl		= tty_ioctl,
+	.compat_ioctl	= tty_compat_ioctl,
 	.open		= tty_open,
 	.release	= tty_release,
 	.fasync		= tty_fasync,
@@ -1169,6 +1197,7 @@ static const struct file_operations ptmx_fops = {
 	.write		= tty_write,
 	.poll		= tty_poll,
 	.ioctl		= tty_ioctl,
+	.compat_ioctl	= tty_compat_ioctl,
 	.open		= ptmx_open,
 	.release	= tty_release,
 	.fasync		= tty_fasync,
@@ -1181,6 +1210,7 @@ static const struct file_operations console_fops = {
 	.write		= redirected_tty_write,
 	.poll		= tty_poll,
 	.ioctl		= tty_ioctl,
+	.compat_ioctl	= tty_compat_ioctl,
 	.open		= tty_open,
 	.release	= tty_release,
 	.fasync		= tty_fasync,
@@ -1191,7 +1221,8 @@ static const struct file_operations hung_up_tty_fops = {
 	.read		= hung_up_tty_read,
 	.write		= hung_up_tty_write,
 	.poll		= hung_up_tty_poll,
-	.ioctl		= hung_up_tty_ioctl,
+	.unlocked_ioctl = hung_up_tty_ioctl,
+	.compat_ioctl	= hung_up_tty_ioctl,
 	.release	= tty_release,
 };
 
@@ -1240,6 +1271,7 @@ void tty_ldisc_flush(struct tty_struct *tty)
 			ld->flush_buffer(tty);
 		tty_ldisc_deref(ld);
 	}
+	tty_buffer_flush(tty);
 }
 
 EXPORT_SYMBOL_GPL(tty_ldisc_flush);
@@ -1534,10 +1566,9 @@ void disassociate_ctty(int on_exit)
 	}
 
 	spin_lock_irq(&current->sighand->siglock);
-	tty_pgrp = current->signal->tty_old_pgrp;
+	put_pid(current->signal->tty_old_pgrp);
 	current->signal->tty_old_pgrp = NULL;
 	spin_unlock_irq(&current->sighand->siglock);
-	put_pid(tty_pgrp);
 
 	mutex_lock(&tty_mutex);
 	/* It is possible that do_tty_hangup has free'd this tty */
@@ -1562,13 +1593,25 @@ void disassociate_ctty(int on_exit)
 	unlock_kernel();
 }
 
+/**
+ *
+ *	no_tty	- Ensure the current process does not have a controlling tty
+ */
+void no_tty(void)
+{
+	struct task_struct *tsk = current;
+	if (tsk->signal->leader)
+		disassociate_ctty(0);
+	proc_clear_tty(tsk);
+}
+
 
 /**
- *	stop_tty	-	propogate flow control
+ *	stop_tty	-	propagate flow control
  *	@tty: tty to stop
  *
  *	Perform flow control to the driver. For PTY/TTY pairs we
- *	must also propogate the TIOCKPKT status. May be called
+ *	must also propagate the TIOCKPKT status. May be called
  *	on an already stopped device and will not re-call the driver
  *	method.
  *
@@ -1598,11 +1641,11 @@ void stop_tty(struct tty_struct *tty)
 EXPORT_SYMBOL(stop_tty);
 
 /**
- *	start_tty	-	propogate flow control
+ *	start_tty	-	propagate flow control
  *	@tty: tty to start
  *
  *	Start a tty that has been stopped if at all possible. Perform
- *	any neccessary wakeups and propogate the TIOCPKT status. If this
+ *	any neccessary wakeups and propagate the TIOCPKT status. If this
  *	is the tty was previous stopped and is being started then the
  *	driver start method is invoked and the line discipline woken.
  *
@@ -2508,7 +2551,6 @@ static int tty_open(struct inode * inode, struct file * filp)
 	int index;
 	dev_t device = inode->i_rdev;
 	unsigned short saved_flags = filp->f_flags;
-	struct pid *old_pgrp;
 
 	nonseekable_open(inode, filp);
 	
@@ -2602,17 +2644,15 @@ got_driver:
 		goto retry_open;
 	}
 
-	old_pgrp = NULL;
 	mutex_lock(&tty_mutex);
 	spin_lock_irq(&current->sighand->siglock);
 	if (!noctty &&
 	    current->signal->leader &&
 	    !current->signal->tty &&
 	    tty->session == NULL)
-		old_pgrp = __proc_set_tty(current, tty);
+		__proc_set_tty(current, tty);
 	spin_unlock_irq(&current->sighand->siglock);
 	mutex_unlock(&tty_mutex);
-	put_pid(old_pgrp);
 	return 0;
 }
 
@@ -3287,9 +3327,7 @@ int tty_ioctl(struct inode * inode, struct file * file,
 		case TIOCNOTTY:
 			if (current->signal->tty != tty)
 				return -ENOTTY;
-			if (current->signal->leader)
-				disassociate_ctty(0);
-			proc_clear_tty(current);
+			no_tty();
 			return 0;
 		case TIOCSCTTY:
 			return tiocsctty(tty, arg);
@@ -3336,6 +3374,15 @@ int tty_ioctl(struct inode * inode, struct file * file,
 		case TIOCMBIC:
 		case TIOCMBIS:
 			return tty_tiocmset(tty, file, cmd, p);
+		case TCFLSH:
+			switch (arg) {
+			case TCIFLUSH:
+			case TCIOFLUSH:
+				/* flush tty buffer and allow ldisc to process ioctl */
+				tty_buffer_flush(tty);
+				break;
+			}
+			break;
 	}
 	if (tty->driver->ioctl) {
 		retval = (tty->driver->ioctl)(tty, file, cmd, arg);
@@ -3353,6 +3400,32 @@ int tty_ioctl(struct inode * inode, struct file * file,
 	return retval;
 }
 
+#ifdef CONFIG_COMPAT
+static long tty_compat_ioctl(struct file * file, unsigned int cmd,
+				unsigned long arg)
+{
+	struct inode *inode = file->f_dentry->d_inode;
+	struct tty_struct *tty = file->private_data;
+	struct tty_ldisc *ld;
+	int retval = -ENOIOCTLCMD;
+
+	if (tty_paranoia_check(tty, inode, "tty_ioctl"))
+		return -EINVAL;
+
+	if (tty->driver->compat_ioctl) {
+		retval = (tty->driver->compat_ioctl)(tty, file, cmd, arg);
+		if (retval != -ENOIOCTLCMD)
+			return retval;
+	}
+
+	ld = tty_ldisc_ref_wait(tty);
+	if (ld->compat_ioctl)
+		retval = ld->compat_ioctl(tty, file, cmd, arg);
+	tty_ldisc_deref(ld);
+
+	return retval;
+}
+#endif
 
 /*
  * This implements the "Secure Attention Key" ---  the idea is to
@@ -3685,6 +3758,7 @@ void tty_set_operations(struct tty_driver *driver,
 	driver->write_room = op->write_room;
 	driver->chars_in_buffer = op->chars_in_buffer;
 	driver->ioctl = op->ioctl;
+	driver->compat_ioctl = op->compat_ioctl;
 	driver->set_termios = op->set_termios;
 	driver->throttle = op->throttle;
 	driver->unthrottle = op->unthrottle;
@@ -3766,7 +3840,9 @@ int tty_register_driver(struct tty_driver *driver)
 	if (!driver->put_char)
 		driver->put_char = tty_default_put_char;
 	
+	mutex_lock(&tty_mutex);
 	list_add(&driver->tty_drivers, &tty_drivers);
+	mutex_unlock(&tty_mutex);
 	
 	if ( !(driver->flags & TTY_DRIVER_DYNAMIC_DEV) ) {
 		for(i = 0; i < driver->num; i++)
@@ -3792,8 +3868,9 @@ int tty_unregister_driver(struct tty_driver *driver)
 
 	unregister_chrdev_region(MKDEV(driver->major, driver->minor_start),
 				driver->num);
-
+	mutex_lock(&tty_mutex);
 	list_del(&driver->tty_drivers);
+	mutex_unlock(&tty_mutex);
 
 	/*
 	 * Free the termios and termios_locked structures because
@@ -3838,9 +3915,8 @@ void proc_clear_tty(struct task_struct *p)
 }
 EXPORT_SYMBOL(proc_clear_tty);
 
-static struct pid *__proc_set_tty(struct task_struct *tsk, struct tty_struct *tty)
+static void __proc_set_tty(struct task_struct *tsk, struct tty_struct *tty)
 {
-	struct pid *old_pgrp;
 	if (tty) {
 		/* We should not have a session or pgrp to here but.... */
 		put_pid(tty->session);
@@ -3848,21 +3924,16 @@ static struct pid *__proc_set_tty(struct task_struct *tsk, struct tty_struct *tt
 		tty->session = get_pid(task_session(tsk));
 		tty->pgrp = get_pid(task_pgrp(tsk));
 	}
-	old_pgrp = tsk->signal->tty_old_pgrp;
+	put_pid(tsk->signal->tty_old_pgrp);
 	tsk->signal->tty = tty;
 	tsk->signal->tty_old_pgrp = NULL;
-	return old_pgrp;
 }
 
-void proc_set_tty(struct task_struct *tsk, struct tty_struct *tty)
+static void proc_set_tty(struct task_struct *tsk, struct tty_struct *tty)
 {
-	struct pid *old_pgrp;
-
 	spin_lock_irq(&tsk->sighand->siglock);
-	old_pgrp = __proc_set_tty(tsk, tty);
+	__proc_set_tty(tsk, tty);
 	spin_unlock_irq(&tsk->sighand->siglock);
-
-	put_pid(old_pgrp);
 }
 
 struct tty_struct *get_current_tty(void)
@@ -3897,9 +3968,6 @@ void __init console_init(void)
 	 * set up the console device so that later boot sequences can 
 	 * inform about problems etc..
 	 */
-#ifdef CONFIG_EARLY_PRINTK
-	disable_early_printk();
-#endif
 	call = __con_initcall_start;
 	while (call < __con_initcall_end) {
 		(*call)();