X-Git-Url: http://git.rot13.org/?a=blobdiff_plain;f=drivers%2Fchar%2Ftty_io.c;h=5289254e7ab3f1e0d0fdfbf48e411e07fdc9c31a;hb=7f1f86a0d04e79f8165e6f50d329a520b8cd11e5;hp=50dc49205a231a2c5854a0e9699e39e5db9e6bed;hpb=4549df891a31b9a05b7d183106c09049b79327be;p=powerpc.git

diff --git a/drivers/char/tty_io.c b/drivers/char/tty_io.c
index 50dc49205a..5289254e7a 100644
--- a/drivers/char/tty_io.c
+++ b/drivers/char/tty_io.c
@@ -109,13 +109,15 @@
 #define TTY_PARANOIA_CHECK 1
 #define CHECK_TTY_COUNT 1
 
-struct termios tty_std_termios = {	/* for the benefit of tty drivers  */
+struct ktermios tty_std_termios = {	/* for the benefit of tty drivers  */
 	.c_iflag = ICRNL | IXON,
 	.c_oflag = OPOST | ONLCR,
 	.c_cflag = B38400 | CS8 | CREAD | HUPCL,
 	.c_lflag = ISIG | ICANON | ECHO | ECHOE | ECHOK |
 		   ECHOCTL | ECHOKE | IEXTEN,
-	.c_cc = INIT_C_CC
+	.c_cc = INIT_C_CC,
+	.c_ispeed = 38400,
+	.c_ospeed = 38400
 };
 
 EXPORT_SYMBOL(tty_std_termios);
@@ -126,7 +128,7 @@ EXPORT_SYMBOL(tty_std_termios);
    
 LIST_HEAD(tty_drivers);			/* linked list of tty drivers */
 
-/* Semaphore to protect creating and releasing a tty. This is shared with
+/* Mutex to protect creating and releasing a tty. This is shared with
    vt.c for deeply disgusting hack reasons */
 DEFINE_MUTEX(tty_mutex);
 EXPORT_SYMBOL(tty_mutex);
@@ -152,7 +154,9 @@ static int tty_release(struct inode *, struct file *);
 int tty_ioctl(struct inode * inode, struct file * file,
 	      unsigned int cmd, unsigned long arg);
 static int tty_fasync(int fd, struct file * filp, int on);
-static void release_mem(struct tty_struct *tty, int idx);
+static void release_tty(struct tty_struct *tty, int idx);
+static struct pid *__proc_set_tty(struct task_struct *tsk,
+				struct tty_struct *tty);
 
 /**
  *	alloc_tty_struct	-	allocate a tty object
@@ -250,7 +254,7 @@ static int check_tty_count(struct tty_struct *tty, const char *routine)
 				    "!= #fd's(%d) in %s\n",
 		       tty->name, tty->count, count, routine);
 		return count;
-       }	
+	}
 #endif
 	return 0;
 }
@@ -259,18 +263,6 @@ static int check_tty_count(struct tty_struct *tty, const char *routine)
  * Tty buffer allocation management
  */
 
-
-/**
- *	tty_buffer_free_all		-	free buffers used by a tty
- *	@tty: tty to free from
- *
- *	Remove all the buffers pending on a tty whether queued with data
- *	or in the free ring. Must be called when the tty is no longer in use
- *
- *	Locking: none
- */
-
-
 /**
  *	tty_buffer_free_all		-	free buffers used by a tty
  *	@tty: tty to free from
@@ -614,7 +606,7 @@ EXPORT_SYMBOL_GPL(tty_prepare_flip_string_flags);
  *	they are not on hot paths so a little discipline won't do 
  *	any harm.
  *
- *	Locking: takes termios_sem
+ *	Locking: takes termios_mutex
  */
  
 static void tty_set_termios_ldisc(struct tty_struct *tty, int num)
@@ -915,7 +907,7 @@ static void tty_ldisc_enable(struct tty_struct *tty)
  *	context.
  *
  *	Locking: takes tty_ldisc_lock.
- *		called functions take termios_sem
+ *		 called functions take termios_mutex
  */
  
 static int tty_set_ldisc(struct tty_struct *tty, int ldisc)
@@ -1119,17 +1111,17 @@ int tty_check_change(struct tty_struct * tty)
 {
 	if (current->signal->tty != tty)
 		return 0;
-	if (tty->pgrp <= 0) {
-		printk(KERN_WARNING "tty_check_change: tty->pgrp <= 0!\n");
+	if (!tty->pgrp) {
+		printk(KERN_WARNING "tty_check_change: tty->pgrp == NULL!\n");
 		return 0;
 	}
-	if (process_group(current) == tty->pgrp)
+	if (task_pgrp(current) == tty->pgrp)
 		return 0;
 	if (is_ignored(SIGTTOU))
 		return 0;
-	if (is_orphaned_pgrp(process_group(current)))
+	if (is_current_pgrp_orphaned())
 		return -EIO;
-	(void) kill_pg(process_group(current), SIGTTOU, 1);
+	(void) kill_pgrp(task_pgrp(current), SIGTTOU, 1);
 	return -ERESTARTSYS;
 }
 
@@ -1251,10 +1243,26 @@ void tty_ldisc_flush(struct tty_struct *tty)
 }
 
 EXPORT_SYMBOL_GPL(tty_ldisc_flush);
+
+/**
+ *	tty_reset_termios	-	reset terminal state
+ *	@tty: tty to reset
+ *
+ *	Restore a terminal to the driver default state
+ */
+
+static void tty_reset_termios(struct tty_struct *tty)
+{
+	mutex_lock(&tty->termios_mutex);
+	*tty->termios = tty->driver->init_termios;
+	tty->termios->c_ispeed = tty_termios_input_baud_rate(tty->termios);
+	tty->termios->c_ospeed = tty_termios_baud_rate(tty->termios);
+	mutex_unlock(&tty->termios_mutex);
+}
 	
 /**
  *	do_tty_hangup		-	actual handler for hangup events
- *	@data: tty device
+ *	@work: tty device
  *
  *	This can be called by the "eventd" kernel thread.  That is process
  *	synchronous but doesn't hold any locks, so we need to make sure we
@@ -1267,16 +1275,17 @@ EXPORT_SYMBOL_GPL(tty_ldisc_flush);
  *
  *	Locking:
  *		BKL
- *		redirect lock for undoing redirection
- *		file list lock for manipulating list of ttys
- *		tty_ldisc_lock from called functions
- *		termios_sem resetting termios data
- *		tasklist_lock to walk task list for hangup event
- *
+ *		  redirect lock for undoing redirection
+ *		  file list lock for manipulating list of ttys
+ *		  tty_ldisc_lock from called functions
+ *		  termios_mutex resetting termios data
+ *		  tasklist_lock to walk task list for hangup event
+ *		    ->siglock to protect ->signal/->sighand
  */
-static void do_tty_hangup(void *data)
+static void do_tty_hangup(struct work_struct *work)
 {
-	struct tty_struct *tty = (struct tty_struct *) data;
+	struct tty_struct *tty =
+		container_of(work, struct tty_struct, hangup_work);
 	struct file * cons_filp = NULL;
 	struct file *filp, *f = NULL;
 	struct task_struct *p;
@@ -1338,11 +1347,7 @@ static void do_tty_hangup(void *data)
 	 * N_TTY.
 	 */
 	if (tty->driver->flags & TTY_DRIVER_RESET_TERMIOS)
-	{
-		mutex_lock(&tty->termios_mutex);
-		*tty->termios = tty->driver->init_termios;
-		mutex_unlock(&tty->termios_mutex);
-	}
+		tty_reset_termios(tty);
 	
 	/* Defer ldisc switch */
 	/* tty_deferred_ldisc_switch(N_TTY);
@@ -1351,23 +1356,28 @@ static void do_tty_hangup(void *data)
 	  tty_release is called */
 	
 	read_lock(&tasklist_lock);
-	if (tty->session > 0) {
-		do_each_task_pid(tty->session, PIDTYPE_SID, p) {
+	if (tty->session) {
+		do_each_pid_task(tty->session, PIDTYPE_SID, p) {
+			spin_lock_irq(&p->sighand->siglock);
 			if (p->signal->tty == tty)
 				p->signal->tty = NULL;
-			if (!p->signal->leader)
+			if (!p->signal->leader) {
+				spin_unlock_irq(&p->sighand->siglock);
 				continue;
-			group_send_sig_info(SIGHUP, SEND_SIG_PRIV, p);
-			group_send_sig_info(SIGCONT, SEND_SIG_PRIV, p);
-			if (tty->pgrp > 0)
-				p->signal->tty_old_pgrp = tty->pgrp;
-		} while_each_task_pid(tty->session, PIDTYPE_SID, p);
+			}
+			__group_send_sig_info(SIGHUP, SEND_SIG_PRIV, p);
+			__group_send_sig_info(SIGCONT, SEND_SIG_PRIV, p);
+			put_pid(p->signal->tty_old_pgrp);  /* A noop */
+			if (tty->pgrp)
+				p->signal->tty_old_pgrp = get_pid(tty->pgrp);
+			spin_unlock_irq(&p->sighand->siglock);
+		} while_each_pid_task(tty->session, PIDTYPE_SID, p);
 	}
 	read_unlock(&tasklist_lock);
 
 	tty->flags = 0;
-	tty->session = 0;
-	tty->pgrp = -1;
+	tty->session = NULL;
+	tty->pgrp = NULL;
 	tty->ctrl_status = 0;
 	/*
 	 *	If one of the devices matches a console pointer, we
@@ -1433,7 +1443,7 @@ void tty_vhangup(struct tty_struct * tty)
 
 	printk(KERN_DEBUG "%s vhangup...\n", tty_name(tty, buf));
 #endif
-	do_tty_hangup((void *) tty);
+	do_tty_hangup(&tty->hangup_work);
 }
 EXPORT_SYMBOL(tty_vhangup);
 
@@ -1452,6 +1462,14 @@ int tty_hung_up_p(struct file * filp)
 
 EXPORT_SYMBOL(tty_hung_up_p);
 
+static void session_clear_tty(struct pid *session)
+{
+	struct task_struct *p;
+	do_each_pid_task(session, PIDTYPE_SID, p) {
+		proc_clear_tty(p);
+	} while_each_pid_task(session, PIDTYPE_SID, p);
+}
+
 /**
  *	disassociate_ctty	-	disconnect controlling tty
  *	@on_exit: true if exiting so need to "hang up" the session
@@ -1468,55 +1486,77 @@ EXPORT_SYMBOL(tty_hung_up_p);
  *	The argument on_exit is set to 1 if called when a process is
  *	exiting; it is 0 if called by the ioctl TIOCNOTTY.
  *
- *	Locking: tty_mutex is taken to protect current->signal->tty
+ *	Locking:
  *		BKL is taken for hysterical raisins
- *		Tasklist lock is taken (under tty_mutex) to walk process
- *		lists for the session.
+ *		  tty_mutex is taken to protect tty
+ *		  ->siglock is taken to protect ->signal/->sighand
+ *		  tasklist_lock is taken to walk process list for sessions
+ *		    ->siglock is taken to protect ->signal/->sighand
  */
 
 void disassociate_ctty(int on_exit)
 {
 	struct tty_struct *tty;
-	struct task_struct *p;
-	int tty_pgrp = -1;
+	struct pid *tty_pgrp = NULL;
 
 	lock_kernel();
 
 	mutex_lock(&tty_mutex);
-	tty = current->signal->tty;
+	tty = get_current_tty();
 	if (tty) {
-		tty_pgrp = tty->pgrp;
+		tty_pgrp = get_pid(tty->pgrp);
 		mutex_unlock(&tty_mutex);
+		/* XXX: here we race, there is nothing protecting tty */
 		if (on_exit && tty->driver->type != TTY_DRIVER_TYPE_PTY)
 			tty_vhangup(tty);
-	} else {
-		if (current->signal->tty_old_pgrp) {
-			kill_pg(current->signal->tty_old_pgrp, SIGHUP, on_exit);
-			kill_pg(current->signal->tty_old_pgrp, SIGCONT, on_exit);
+	} else if (on_exit) {
+		struct pid *old_pgrp;
+		spin_lock_irq(&current->sighand->siglock);
+		old_pgrp = current->signal->tty_old_pgrp;
+		current->signal->tty_old_pgrp = NULL;
+		spin_unlock_irq(&current->sighand->siglock);
+		if (old_pgrp) {
+			kill_pgrp(old_pgrp, SIGHUP, on_exit);
+			kill_pgrp(old_pgrp, SIGCONT, on_exit);
+			put_pid(old_pgrp);
 		}
 		mutex_unlock(&tty_mutex);
 		unlock_kernel();	
 		return;
 	}
-	if (tty_pgrp > 0) {
-		kill_pg(tty_pgrp, SIGHUP, on_exit);
+	if (tty_pgrp) {
+		kill_pgrp(tty_pgrp, SIGHUP, on_exit);
 		if (!on_exit)
-			kill_pg(tty_pgrp, SIGCONT, on_exit);
+			kill_pgrp(tty_pgrp, SIGCONT, on_exit);
+		put_pid(tty_pgrp);
 	}
 
-	/* Must lock changes to tty_old_pgrp */
-	mutex_lock(&tty_mutex);
+	spin_lock_irq(&current->sighand->siglock);
+	tty_pgrp = current->signal->tty_old_pgrp;
 	current->signal->tty_old_pgrp = 0;
-	tty->session = 0;
-	tty->pgrp = -1;
+	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 */
+	tty = get_current_tty();
+	if (tty) {
+		put_pid(tty->session);
+		put_pid(tty->pgrp);
+		tty->session = NULL;
+		tty->pgrp = NULL;
+	} else {
+#ifdef TTY_DEBUG_HANGUP
+		printk(KERN_DEBUG "error attempted to write to tty [0x%p]"
+		       " = NULL", tty);
+#endif
+	}
+	mutex_unlock(&tty_mutex);
 
 	/* Now clear signal->tty under the lock */
 	read_lock(&tasklist_lock);
-	do_each_task_pid(current->signal->session, PIDTYPE_SID, p) {
-		p->signal->tty = NULL;
-	} while_each_task_pid(current->signal->session, PIDTYPE_SID, p);
+	session_clear_tty(task_session(current));
 	read_unlock(&tasklist_lock);
-	mutex_unlock(&tty_mutex);
 	unlock_kernel();
 }
 
@@ -1583,7 +1623,6 @@ void start_tty(struct tty_struct *tty)
 
 	/* If we have a running line discipline it may need kicking */
 	tty_wakeup(tty);
-	wake_up_interruptible(&tty->write_wait);
 }
 
 EXPORT_SYMBOL(start_tty);
@@ -1614,7 +1653,7 @@ static ssize_t tty_read(struct file * file, char __user * buf, size_t count,
 	struct tty_ldisc *ld;
 
 	tty = (struct tty_struct *)file->private_data;
-	inode = file->f_dentry->d_inode;
+	inode = file->f_path.dentry->d_inode;
 	if (tty_paranoia_check(tty, inode, "tty_read"))
 		return -EIO;
 	if (!tty || (test_bit(TTY_IO_ERROR, &tty->flags)))
@@ -1717,7 +1756,7 @@ static inline ssize_t do_tty_write(
 		cond_resched();
 	}
 	if (written) {
-		struct inode *inode = file->f_dentry->d_inode;
+		struct inode *inode = file->f_path.dentry->d_inode;
 		inode->i_mtime = current_fs_time(inode->i_sb);
 		ret = written;
 	}
@@ -1748,7 +1787,7 @@ static ssize_t tty_write(struct file * file, const char __user * buf, size_t cou
 			 loff_t *ppos)
 {
 	struct tty_struct * tty;
-	struct inode *inode = file->f_dentry->d_inode;
+	struct inode *inode = file->f_path.dentry->d_inode;
 	ssize_t ret;
 	struct tty_ldisc *ld;
 	
@@ -1855,8 +1894,8 @@ static int init_dev(struct tty_driver *driver, int idx,
 	struct tty_struct **ret_tty)
 {
 	struct tty_struct *tty, *o_tty;
-	struct termios *tp, **tp_loc, *o_tp, **o_tp_loc;
-	struct termios *ltp, **ltp_loc, *o_ltp, **o_ltp_loc;
+	struct ktermios *tp, **tp_loc, *o_tp, **o_tp_loc;
+	struct ktermios *ltp, **ltp_loc, *o_ltp, **o_ltp_loc;
 	int retval = 0;
 
 	/* check whether we're reopening an existing tty */
@@ -1903,7 +1942,7 @@ static int init_dev(struct tty_driver *driver, int idx,
 	}
 
 	if (!*tp_loc) {
-		tp = (struct termios *) kmalloc(sizeof(struct termios),
+		tp = (struct ktermios *) kmalloc(sizeof(struct ktermios),
 						GFP_KERNEL);
 		if (!tp)
 			goto free_mem_out;
@@ -1911,11 +1950,11 @@ static int init_dev(struct tty_driver *driver, int idx,
 	}
 
 	if (!*ltp_loc) {
-		ltp = (struct termios *) kmalloc(sizeof(struct termios),
+		ltp = (struct ktermios *) kmalloc(sizeof(struct ktermios),
 						 GFP_KERNEL);
 		if (!ltp)
 			goto free_mem_out;
-		memset(ltp, 0, sizeof(struct termios));
+		memset(ltp, 0, sizeof(struct ktermios));
 	}
 
 	if (driver->type == TTY_DRIVER_TYPE_PTY) {
@@ -1936,19 +1975,19 @@ static int init_dev(struct tty_driver *driver, int idx,
 		}
 
 		if (!*o_tp_loc) {
-			o_tp = (struct termios *)
-				kmalloc(sizeof(struct termios), GFP_KERNEL);
+			o_tp = (struct ktermios *)
+				kmalloc(sizeof(struct ktermios), GFP_KERNEL);
 			if (!o_tp)
 				goto free_mem_out;
 			*o_tp = driver->other->init_termios;
 		}
 
 		if (!*o_ltp_loc) {
-			o_ltp = (struct termios *)
-				kmalloc(sizeof(struct termios), GFP_KERNEL);
+			o_ltp = (struct ktermios *)
+				kmalloc(sizeof(struct ktermios), GFP_KERNEL);
 			if (!o_ltp)
 				goto free_mem_out;
-			memset(o_ltp, 0, sizeof(struct termios));
+			memset(o_ltp, 0, sizeof(struct ktermios));
 		}
 
 		/*
@@ -1974,7 +2013,7 @@ static int init_dev(struct tty_driver *driver, int idx,
 
 	/* 
 	 * All structures have been allocated, so now we install them.
-	 * Failures after this point use release_mem to clean up, so 
+	 * Failures after this point use release_tty to clean up, so
 	 * there's no need to null out the local pointers.
 	 */
 	if (!(driver->flags & TTY_DRIVER_DEVPTS_MEM)) {
@@ -1987,13 +2026,16 @@ static int init_dev(struct tty_driver *driver, int idx,
 		*ltp_loc = ltp;
 	tty->termios = *tp_loc;
 	tty->termios_locked = *ltp_loc;
+	/* Compatibility until drivers always set this */
+	tty->termios->c_ispeed = tty_termios_input_baud_rate(tty->termios);
+	tty->termios->c_ospeed = tty_termios_baud_rate(tty->termios);
 	driver->refcount++;
 	tty->count++;
 
 	/* 
 	 * Structures all installed ... call the ldisc open routines.
-	 * If we fail here just call release_mem to clean up.  No need
-	 * to decrement the use counts, as release_mem doesn't care.
+	 * If we fail here just call release_tty to clean up.  No need
+	 * to decrement the use counts, as release_tty doesn't care.
 	 */
 
 	if (tty->ldisc.open) {
@@ -2063,17 +2105,17 @@ fail_no_mem:
 	retval = -ENOMEM;
 	goto end_init;
 
-	/* call the tty release_mem routine to clean out this slot */
+	/* call the tty release_tty routine to clean out this slot */
 release_mem_out:
 	if (printk_ratelimit())
 		printk(KERN_INFO "init_dev: ldisc open failed, "
 				 "clearing slot %d\n", idx);
-	release_mem(tty, idx);
+	release_tty(tty, idx);
 	goto end_init;
 }
 
 /**
- *	release_mem		-	release tty structure memory
+ *	release_one_tty		-	release tty structure memory
  *
  *	Releases memory associated with a tty structure, and clears out the
  *	driver table slots. This function is called when a device is no longer
@@ -2085,37 +2127,14 @@ release_mem_out:
  *	of ttys that the driver keeps.
  *		FIXME: should we require tty_mutex is held here ??
  */
-
-static void release_mem(struct tty_struct *tty, int idx)
+static void release_one_tty(struct tty_struct *tty, int idx)
 {
-	struct tty_struct *o_tty;
-	struct termios *tp;
 	int devpts = tty->driver->flags & TTY_DRIVER_DEVPTS_MEM;
-
-	if ((o_tty = tty->link) != NULL) {
-		if (!devpts)
-			o_tty->driver->ttys[idx] = NULL;
-		if (o_tty->driver->flags & TTY_DRIVER_RESET_TERMIOS) {
-			tp = o_tty->termios;
-			if (!devpts)
-				o_tty->driver->termios[idx] = NULL;
-			kfree(tp);
-
-			tp = o_tty->termios_locked;
-			if (!devpts)
-				o_tty->driver->termios_locked[idx] = NULL;
-			kfree(tp);
-		}
-		o_tty->magic = 0;
-		o_tty->driver->refcount--;
-		file_list_lock();
-		list_del_init(&o_tty->tty_files);
-		file_list_unlock();
-		free_tty_struct(o_tty);
-	}
+	struct ktermios *tp;
 
 	if (!devpts)
 		tty->driver->ttys[idx] = NULL;
+
 	if (tty->driver->flags & TTY_DRIVER_RESET_TERMIOS) {
 		tp = tty->termios;
 		if (!devpts)
@@ -2128,15 +2147,39 @@ static void release_mem(struct tty_struct *tty, int idx)
 		kfree(tp);
 	}
 
+
 	tty->magic = 0;
 	tty->driver->refcount--;
+
 	file_list_lock();
 	list_del_init(&tty->tty_files);
 	file_list_unlock();
-	module_put(tty->driver->owner);
+
 	free_tty_struct(tty);
 }
 
+/**
+ *	release_tty		-	release tty structure memory
+ *
+ *	Release both @tty and a possible linked partner (think pty pair),
+ *	and decrement the refcount of the backing module.
+ *
+ *	Locking:
+ *		tty_mutex - sometimes only
+ *		takes the file list lock internally when working on the list
+ *	of ttys that the driver keeps.
+ *		FIXME: should we require tty_mutex is held here ??
+ */
+static void release_tty(struct tty_struct *tty, int idx)
+{
+	struct tty_driver *driver = tty->driver;
+
+	if (tty->link)
+		release_one_tty(tty->link, idx);
+	release_one_tty(tty, idx);
+	module_put(driver->owner);
+}
+
 /*
  * Even releasing the tty structures is a tricky business.. We have
  * to be very careful that the structures are all released at the
@@ -2155,7 +2198,7 @@ static void release_dev(struct file * filp)
 	unsigned long flags;
 	
 	tty = (struct tty_struct *)filp->private_data;
-	if (tty_paranoia_check(tty, filp->f_dentry->d_inode, "release_dev"))
+	if (tty_paranoia_check(tty, filp->f_path.dentry->d_inode, "release_dev"))
 		return;
 
 	check_tty_count(tty, "release_dev");
@@ -2336,16 +2379,10 @@ static void release_dev(struct file * filp)
 	 * tty.
 	 */
 	if (tty_closing || o_tty_closing) {
-		struct task_struct *p;
-
 		read_lock(&tasklist_lock);
-		do_each_task_pid(tty->session, PIDTYPE_SID, p) {
-			p->signal->tty = NULL;
-		} while_each_task_pid(tty->session, PIDTYPE_SID, p);
+		session_clear_tty(tty->session);
 		if (o_tty)
-			do_each_task_pid(o_tty->session, PIDTYPE_SID, p) {
-				p->signal->tty = NULL;
-			} while_each_task_pid(o_tty->session, PIDTYPE_SID, p);
+			session_clear_tty(o_tty->session);
 		read_unlock(&tasklist_lock);
 	}
 
@@ -2410,10 +2447,10 @@ static void release_dev(struct file * filp)
 		tty_set_termios_ldisc(o_tty,N_TTY); 
 	}
 	/*
-	 * The release_mem function takes care of the details of clearing
+	 * The release_tty function takes care of the details of clearing
 	 * the slots and preserving the termios structure.
 	 */
-	release_mem(tty, idx);
+	release_tty(tty, idx);
 
 #ifdef CONFIG_UNIX98_PTYS
 	/* Make this pty number available for reallocation */
@@ -2442,9 +2479,9 @@ static void release_dev(struct file * filp)
  *	The termios state of a pty is reset on first open so that
  *	settings don't persist across reuse.
  *
- *	Locking: tty_mutex protects current->signal->tty, get_tty_driver and
- *		init_dev work. tty->count should protect the rest.
- *		task_lock is held to update task details for sessions
+ *	Locking: tty_mutex protects tty, get_tty_driver and init_dev work.
+ *		 tty->count should protect the rest.
+ *		 ->siglock protects ->signal/->sighand
  */
 
 static int tty_open(struct inode * inode, struct file * filp)
@@ -2455,6 +2492,7 @@ 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);
 	
@@ -2466,12 +2504,13 @@ retry_open:
 	mutex_lock(&tty_mutex);
 
 	if (device == MKDEV(TTYAUX_MAJOR,0)) {
-		if (!current->signal->tty) {
+		tty = get_current_tty();
+		if (!tty) {
 			mutex_unlock(&tty_mutex);
 			return -ENXIO;
 		}
-		driver = current->signal->tty->driver;
-		index = current->signal->tty->index;
+		driver = tty->driver;
+		index = tty->index;
 		filp->f_flags |= O_NONBLOCK; /* Don't let /dev/tty block */
 		/* noctty = 1; */
 		goto got_driver;
@@ -2546,17 +2585,18 @@ got_driver:
 			filp->f_op = &tty_fops;
 		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 == 0) {
-	    	task_lock(current);
-		current->signal->tty = tty;
-		task_unlock(current);
-		current->signal->tty_old_pgrp = 0;
-		tty->session = current->signal->session;
-		tty->pgrp = process_group(current);
-	}
+	    tty->session == NULL)
+		old_pgrp = __proc_set_tty(current, tty);
+	spin_unlock_irq(&current->sighand->siglock);
+	mutex_unlock(&tty_mutex);
+	put_pid(old_pgrp);
 	return 0;
 }
 
@@ -2671,7 +2711,7 @@ static unsigned int tty_poll(struct file * filp, poll_table * wait)
 	int ret = 0;
 
 	tty = (struct tty_struct *)filp->private_data;
-	if (tty_paranoia_check(tty, filp->f_dentry->d_inode, "tty_poll"))
+	if (tty_paranoia_check(tty, filp->f_path.dentry->d_inode, "tty_poll"))
 		return 0;
 		
 	ld = tty_ldisc_ref_wait(tty);
@@ -2687,7 +2727,7 @@ static int tty_fasync(int fd, struct file * filp, int on)
 	int retval;
 
 	tty = (struct tty_struct *)filp->private_data;
-	if (tty_paranoia_check(tty, filp->f_dentry->d_inode, "tty_fasync"))
+	if (tty_paranoia_check(tty, filp->f_path.dentry->d_inode, "tty_fasync"))
 		return 0;
 	
 	retval = fasync_helper(fd, filp, on, &tty->fasync);
@@ -2695,9 +2735,18 @@ static int tty_fasync(int fd, struct file * filp, int on)
 		return retval;
 
 	if (on) {
+		enum pid_type type;
+		struct pid *pid;
 		if (!waitqueue_active(&tty->read_wait))
 			tty->minimum_to_wake = 1;
-		retval = f_setown(filp, (-tty->pgrp) ? : current->pid, 0);
+		if (tty->pgrp) {
+			pid = tty->pgrp;
+			type = PIDTYPE_PGID;
+		} else {
+			pid = task_pid(current);
+			type = PIDTYPE_PID;
+		}
+		retval = __f_setown(filp, pid, type, 0);
 		if (retval)
 			return retval;
 	} else {
@@ -2746,7 +2795,7 @@ static int tiocsti(struct tty_struct *tty, char __user *p)
  *
  *	Copies the kernel idea of the window size into the user buffer.
  *
- *	Locking: tty->termios_sem is taken to ensure the winsize data
+ *	Locking: tty->termios_mutex is taken to ensure the winsize data
  *		is consistent.
  */
 
@@ -2773,8 +2822,8 @@ static int tiocgwinsz(struct tty_struct *tty, struct winsize __user * arg)
  *	Locking:
  *		Called function use the console_sem is used to ensure we do
  *	not try and resize the console twice at once.
- *		The tty->termios_sem is used to ensure we don't double
- *	resize and get confused. Lock order - tty->termios.sem before
+ *		The tty->termios_mutex is used to ensure we don't double
+ *	resize and get confused. Lock order - tty->termios_mutex before
  *	console sem
  */
 
@@ -2799,10 +2848,10 @@ static int tiocswinsz(struct tty_struct *tty, struct tty_struct *real_tty,
 		}
 	}
 #endif
-	if (tty->pgrp > 0)
-		kill_pg(tty->pgrp, SIGWINCH, 1);
-	if ((real_tty->pgrp != tty->pgrp) && (real_tty->pgrp > 0))
-		kill_pg(real_tty->pgrp, SIGWINCH, 1);
+	if (tty->pgrp)
+		kill_pgrp(tty->pgrp, SIGWINCH, 1);
+	if ((real_tty->pgrp != tty->pgrp) && real_tty->pgrp)
+		kill_pgrp(real_tty->pgrp, SIGWINCH, 1);
 	tty->winsize = tmp_ws;
 	real_tty->winsize = tmp_ws;
 done:
@@ -2879,26 +2928,28 @@ static int fionbio(struct file *file, int __user *p)
  *	leader to set this tty as the controlling tty for the session.
  *
  *	Locking:
- *		Takes tasklist lock internally to walk sessions
- *		Takes task_lock() when updating signal->tty
  *		Takes tty_mutex() to protect tty instance
- *
+ *		Takes tasklist_lock internally to walk sessions
+ *		Takes ->siglock() when updating signal->tty
  */
 
 static int tiocsctty(struct tty_struct *tty, int arg)
 {
-	struct task_struct *p;
+	int ret = 0;
+	if (current->signal->leader && (task_session(current) == tty->session))
+		return ret;
 
-	if (current->signal->leader &&
-	    (current->signal->session == tty->session))
-		return 0;
+	mutex_lock(&tty_mutex);
 	/*
 	 * The process must be a session leader and
 	 * not have a controlling tty already.
 	 */
-	if (!current->signal->leader || current->signal->tty)
-		return -EPERM;
-	if (tty->session > 0) {
+	if (!current->signal->leader || current->signal->tty) {
+		ret = -EPERM;
+		goto unlock;
+	}
+
+	if (tty->session) {
 		/*
 		 * This tty is already the controlling
 		 * tty for another session group!
@@ -2907,24 +2958,18 @@ static int tiocsctty(struct tty_struct *tty, int arg)
 			/*
 			 * Steal it away
 			 */
-
 			read_lock(&tasklist_lock);
-			do_each_task_pid(tty->session, PIDTYPE_SID, p) {
-				p->signal->tty = NULL;
-			} while_each_task_pid(tty->session, PIDTYPE_SID, p);
+			session_clear_tty(tty->session);
 			read_unlock(&tasklist_lock);
-		} else
-			return -EPERM;
+		} else {
+			ret = -EPERM;
+			goto unlock;
+		}
 	}
-	mutex_lock(&tty_mutex);
-	task_lock(current);
-	current->signal->tty = tty;
-	task_unlock(current);
+	proc_set_tty(current, tty);
+unlock:
 	mutex_unlock(&tty_mutex);
-	current->signal->tty_old_pgrp = 0;
-	tty->session = current->signal->session;
-	tty->pgrp = process_group(current);
-	return 0;
+	return ret;
 }
 
 /**
@@ -2936,7 +2981,7 @@ static int tiocsctty(struct tty_struct *tty, int arg)
  *	Obtain the process group of the tty. If there is no process group
  *	return an error.
  *
- *	Locking: none. Reference to ->signal->tty is safe.
+ *	Locking: none. Reference to current->signal->tty is safe.
  */
 
 static int tiocgpgrp(struct tty_struct *tty, struct tty_struct *real_tty, pid_t __user *p)
@@ -2947,7 +2992,7 @@ static int tiocgpgrp(struct tty_struct *tty, struct tty_struct *real_tty, pid_t
 	 */
 	if (tty == real_tty && current->signal->tty != real_tty)
 		return -ENOTTY;
-	return put_user(real_tty->pgrp, p);
+	return put_user(pid_nr(real_tty->pgrp), p);
 }
 
 /**
@@ -2964,7 +3009,8 @@ static int tiocgpgrp(struct tty_struct *tty, struct tty_struct *real_tty, pid_t
 
 static int tiocspgrp(struct tty_struct *tty, struct tty_struct *real_tty, pid_t __user *p)
 {
-	pid_t pgrp;
+	struct pid *pgrp;
+	pid_t pgrp_nr;
 	int retval = tty_check_change(real_tty);
 
 	if (retval == -EIO)
@@ -2973,16 +3019,26 @@ static int tiocspgrp(struct tty_struct *tty, struct tty_struct *real_tty, pid_t
 		return retval;
 	if (!current->signal->tty ||
 	    (current->signal->tty != real_tty) ||
-	    (real_tty->session != current->signal->session))
+	    (real_tty->session != task_session(current)))
 		return -ENOTTY;
-	if (get_user(pgrp, p))
+	if (get_user(pgrp_nr, p))
 		return -EFAULT;
-	if (pgrp < 0)
+	if (pgrp_nr < 0)
 		return -EINVAL;
-	if (session_of_pgrp(pgrp) != current->signal->session)
-		return -EPERM;
-	real_tty->pgrp = pgrp;
-	return 0;
+	rcu_read_lock();
+	pgrp = find_pid(pgrp_nr);
+	retval = -ESRCH;
+	if (!pgrp)
+		goto out_unlock;
+	retval = -EPERM;
+	if (session_of_pgrp(pgrp) != task_session(current))
+		goto out_unlock;
+	retval = 0;
+	put_pid(real_tty->pgrp);
+	real_tty->pgrp = get_pid(pgrp);
+out_unlock:
+	rcu_read_unlock();
+	return retval;
 }
 
 /**
@@ -2994,7 +3050,7 @@ static int tiocspgrp(struct tty_struct *tty, struct tty_struct *real_tty, pid_t
  *	Obtain the session id of the tty. If there is no session
  *	return an error.
  *
- *	Locking: none. Reference to ->signal->tty is safe.
+ *	Locking: none. Reference to current->signal->tty is safe.
  */
 
 static int tiocgsid(struct tty_struct *tty, struct tty_struct *real_tty, pid_t __user *p)
@@ -3005,9 +3061,9 @@ static int tiocgsid(struct tty_struct *tty, struct tty_struct *real_tty, pid_t _
 	*/
 	if (tty == real_tty && current->signal->tty != real_tty)
 		return -ENOTTY;
-	if (real_tty->session <= 0)
+	if (!real_tty->session)
 		return -ENOTTY;
-	return put_user(real_tty->session, p);
+	return put_user(pid_nr(real_tty->session), p);
 }
 
 /**
@@ -3213,14 +3269,11 @@ int tty_ioctl(struct inode * inode, struct file * file,
 			clear_bit(TTY_EXCLUSIVE, &tty->flags);
 			return 0;
 		case TIOCNOTTY:
-			/* FIXME: taks lock or tty_mutex ? */
 			if (current->signal->tty != tty)
 				return -ENOTTY;
 			if (current->signal->leader)
 				disassociate_ctty(0);
-			task_lock(current);
-			current->signal->tty = NULL;
-			task_unlock(current);
+			proc_clear_tty(current);
 			return 0;
 		case TIOCSCTTY:
 			return tiocsctty(tty, arg);
@@ -3304,47 +3357,41 @@ int tty_ioctl(struct inode * inode, struct file * file,
  * Nasty bug: do_SAK is being called in interrupt context.  This can
  * deadlock.  We punt it up to process context.  AKPM - 16Mar2001
  */
-static void __do_SAK(void *arg)
+void __do_SAK(struct tty_struct *tty)
 {
 #ifdef TTY_SOFT_SAK
 	tty_hangup(tty);
 #else
-	struct tty_struct *tty = arg;
 	struct task_struct *g, *p;
-	int session;
+	struct pid *session;
 	int		i;
 	struct file	*filp;
-	struct tty_ldisc *disc;
 	struct fdtable *fdt;
 	
 	if (!tty)
 		return;
-	session  = tty->session;
+	session = tty->session;
 	
-	/* We don't want an ldisc switch during this */
-	disc = tty_ldisc_ref(tty);
-	if (disc && disc->flush_buffer)
-		disc->flush_buffer(tty);
-	tty_ldisc_deref(disc);
+	tty_ldisc_flush(tty);
 
 	if (tty->driver->flush_buffer)
 		tty->driver->flush_buffer(tty);
 	
 	read_lock(&tasklist_lock);
 	/* Kill the entire session */
-	do_each_task_pid(session, PIDTYPE_SID, p) {
+	do_each_pid_task(session, PIDTYPE_SID, p) {
 		printk(KERN_NOTICE "SAK: killed process %d"
-			" (%s): p->signal->session==tty->session\n",
+			" (%s): process_session(p)==tty->session\n",
 			p->pid, p->comm);
 		send_sig(SIGKILL, p, 1);
-	} while_each_task_pid(session, PIDTYPE_SID, p);
+	} while_each_pid_task(session, PIDTYPE_SID, p);
 	/* Now kill any processes that happen to have the
 	 * tty open.
 	 */
 	do_each_thread(g, p) {
 		if (p->signal->tty == tty) {
 			printk(KERN_NOTICE "SAK: killed process %d"
-			    " (%s): p->signal->session==tty->session\n",
+			    " (%s): process_session(p)==tty->session\n",
 			    p->pid, p->comm);
 			send_sig(SIGKILL, p, 1);
 			continue;
@@ -3378,6 +3425,13 @@ static void __do_SAK(void *arg)
 #endif
 }
 
+static void do_SAK_work(struct work_struct *work)
+{
+	struct tty_struct *tty =
+		container_of(work, struct tty_struct, SAK_work);
+	__do_SAK(tty);
+}
+
 /*
  * The tq handling here is a little racy - tty->SAK_work may already be queued.
  * Fortunately we don't need to worry, because if ->SAK_work is already queued,
@@ -3388,7 +3442,6 @@ void do_SAK(struct tty_struct *tty)
 {
 	if (!tty)
 		return;
-	PREPARE_WORK(&tty->SAK_work, __do_SAK, tty);
 	schedule_work(&tty->SAK_work);
 }
 
@@ -3396,7 +3449,7 @@ EXPORT_SYMBOL(do_SAK);
 
 /**
  *	flush_to_ldisc
- *	@private_: tty structure passed from work queue.
+ *	@work: tty structure passed from work queue.
  *
  *	This routine is called out of the software interrupt to flush data
  *	from the buffer chain to the line discipline.
@@ -3406,9 +3459,10 @@ EXPORT_SYMBOL(do_SAK);
  *	receive_buf method is single threaded for each tty instance.
  */
  
-static void flush_to_ldisc(void *private_)
+static void flush_to_ldisc(struct work_struct *work)
 {
-	struct tty_struct *tty = (struct tty_struct *) private_;
+	struct tty_struct *tty =
+		container_of(work, struct tty_struct, buf.work.work);
 	unsigned long 	flags;
 	struct tty_ldisc *disc;
 	struct tty_buffer *tbuf, *head;
@@ -3453,84 +3507,6 @@ static void flush_to_ldisc(void *private_)
 	tty_ldisc_deref(disc);
 }
 
-/*
- * Routine which returns the baud rate of the tty
- *
- * Note that the baud_table needs to be kept in sync with the
- * include/asm/termbits.h file.
- */
-static int baud_table[] = {
-	0, 50, 75, 110, 134, 150, 200, 300, 600, 1200, 1800, 2400, 4800,
-	9600, 19200, 38400, 57600, 115200, 230400, 460800,
-#ifdef __sparc__
-	76800, 153600, 307200, 614400, 921600
-#else
-	500000, 576000, 921600, 1000000, 1152000, 1500000, 2000000,
-	2500000, 3000000, 3500000, 4000000
-#endif
-};
-
-static int n_baud_table = ARRAY_SIZE(baud_table);
-
-/**
- *	tty_termios_baud_rate
- *	@termios: termios structure
- *
- *	Convert termios baud rate data into a speed. This should be called
- *	with the termios lock held if this termios is a terminal termios
- *	structure. May change the termios data.
- *
- *	Locking: none
- */
- 
-int tty_termios_baud_rate(struct termios *termios)
-{
-	unsigned int cbaud;
-	
-	cbaud = termios->c_cflag & CBAUD;
-
-	if (cbaud & CBAUDEX) {
-		cbaud &= ~CBAUDEX;
-
-		if (cbaud < 1 || cbaud + 15 > n_baud_table)
-			termios->c_cflag &= ~CBAUDEX;
-		else
-			cbaud += 15;
-	}
-	return baud_table[cbaud];
-}
-
-EXPORT_SYMBOL(tty_termios_baud_rate);
-
-/**
- *	tty_get_baud_rate	-	get tty bit rates
- *	@tty: tty to query
- *
- *	Returns the baud rate as an integer for this terminal. The
- *	termios lock must be held by the caller and the terminal bit
- *	flags may be updated.
- *
- *	Locking: none
- */
- 
-int tty_get_baud_rate(struct tty_struct *tty)
-{
-	int baud = tty_termios_baud_rate(tty->termios);
-
-	if (baud == 38400 && tty->alt_speed) {
-		if (!tty->warned) {
-			printk(KERN_WARNING "Use of setserial/setrocket to "
-					    "set SPD_* flags is deprecated\n");
-			tty->warned = 1;
-		}
-		baud = tty->alt_speed;
-	}
-	
-	return baud;
-}
-
-EXPORT_SYMBOL(tty_get_baud_rate);
-
 /**
  *	tty_flip_buffer_push	-	terminal
  *	@tty: tty to push
@@ -3553,7 +3529,7 @@ void tty_flip_buffer_push(struct tty_struct *tty)
 	spin_unlock_irqrestore(&tty->buf.lock, flags);
 
 	if (tty->low_latency)
-		flush_to_ldisc((void *) tty);
+		flush_to_ldisc(&tty->buf.work.work);
 	else
 		schedule_delayed_work(&tty->buf.work, 1);
 }
@@ -3576,21 +3552,22 @@ static void initialize_tty_struct(struct tty_struct *tty)
 	memset(tty, 0, sizeof(struct tty_struct));
 	tty->magic = TTY_MAGIC;
 	tty_ldisc_assign(tty, tty_ldisc_get(N_TTY));
-	tty->pgrp = -1;
+	tty->session = NULL;
+	tty->pgrp = NULL;
 	tty->overrun_time = jiffies;
 	tty->buf.head = tty->buf.tail = NULL;
 	tty_buffer_init(tty);
-	INIT_WORK(&tty->buf.work, flush_to_ldisc, tty);
+	INIT_DELAYED_WORK(&tty->buf.work, flush_to_ldisc);
 	init_MUTEX(&tty->buf.pty_sem);
 	mutex_init(&tty->termios_mutex);
 	init_waitqueue_head(&tty->write_wait);
 	init_waitqueue_head(&tty->read_wait);
-	INIT_WORK(&tty->hangup_work, do_tty_hangup, tty);
+	INIT_WORK(&tty->hangup_work, do_tty_hangup);
 	mutex_init(&tty->atomic_read_lock);
 	mutex_init(&tty->atomic_write_lock);
 	spin_lock_init(&tty->read_lock);
 	INIT_LIST_HEAD(&tty->tty_files);
-	INIT_WORK(&tty->SAK_work, NULL, NULL);
+	INIT_WORK(&tty->SAK_work, do_SAK_work);
 }
 
 /*
@@ -3753,8 +3730,8 @@ int tty_register_driver(struct tty_driver *driver)
 
 	if (p) {
 		driver->ttys = (struct tty_struct **)p;
-		driver->termios = (struct termios **)(p + driver->num);
-		driver->termios_locked = (struct termios **)(p + driver->num * 2);
+		driver->termios = (struct ktermios **)(p + driver->num);
+		driver->termios_locked = (struct ktermios **)(p + driver->num * 2);
 	} else {
 		driver->ttys = NULL;
 		driver->termios = NULL;
@@ -3793,7 +3770,7 @@ EXPORT_SYMBOL(tty_register_driver);
 int tty_unregister_driver(struct tty_driver *driver)
 {
 	int i;
-	struct termios *tp;
+	struct ktermios *tp;
 	void *p;
 
 	if (driver->refcount)
@@ -3831,9 +3808,60 @@ int tty_unregister_driver(struct tty_driver *driver)
 	cdev_del(&driver->cdev);
 	return 0;
 }
-
 EXPORT_SYMBOL(tty_unregister_driver);
 
+dev_t tty_devnum(struct tty_struct *tty)
+{
+	return MKDEV(tty->driver->major, tty->driver->minor_start) + tty->index;
+}
+EXPORT_SYMBOL(tty_devnum);
+
+void proc_clear_tty(struct task_struct *p)
+{
+	spin_lock_irq(&p->sighand->siglock);
+	p->signal->tty = NULL;
+	spin_unlock_irq(&p->sighand->siglock);
+}
+EXPORT_SYMBOL(proc_clear_tty);
+
+static struct pid *__proc_set_tty(struct task_struct *tsk, struct tty_struct *tty)
+{
+	struct pid *old_pgrp;
+	if (tty) {
+		tty->session = get_pid(task_session(tsk));
+		tty->pgrp = get_pid(task_pgrp(tsk));
+	}
+	old_pgrp = 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)
+{
+	struct pid *old_pgrp;
+
+	spin_lock_irq(&tsk->sighand->siglock);
+	old_pgrp = __proc_set_tty(tsk, tty);
+	spin_unlock_irq(&tsk->sighand->siglock);
+
+	put_pid(old_pgrp);
+}
+
+struct tty_struct *get_current_tty(void)
+{
+	struct tty_struct *tty;
+	WARN_ON_ONCE(!mutex_is_locked(&tty_mutex));
+	tty = current->signal->tty;
+	/*
+	 * session->tty can be changed/cleared from under us, make sure we
+	 * issue the load. The obtained pointer, when not NULL, is valid as
+	 * long as we hold tty_mutex.
+	 */
+	barrier();
+	return tty;
+}
+EXPORT_SYMBOL_GPL(get_current_tty);
 
 /*
  * Initialize the console device. This is called *early*, so