4 files changed, 61 insertions, 5 deletions

diff --git a/drivers/tty/hvc/Kconfig b/drivers/tty/hvc/Kconfig
index 574da15fe618..b8d5ea0ae26b 100644
--- a/drivers/tty/hvc/Kconfig
+++ b/drivers/tty/hvc/Kconfig
@@ -44,7 +44,7 @@ config HVC_RTAS
 
 config HVC_IUCV
 	bool "z/VM IUCV Hypervisor console support (VM only)"
-	depends on S390
+	depends on S390 && NET
 	select HVC_DRIVER
 	select IUCV
 	default y
diff --git a/drivers/tty/synclink_gt.c b/drivers/tty/synclink_gt.c
index 31885f20fc15..cc047de72e2a 100644
--- a/drivers/tty/synclink_gt.c
+++ b/drivers/tty/synclink_gt.c
@@ -184,7 +184,7 @@ static void hdlcdev_exit(struct slgt_info *info);
 struct cond_wait {
 	struct cond_wait *next;
 	wait_queue_head_t q;
-	wait_queue_t wait;
+	wait_queue_entry_t wait;
 	unsigned int data;
 };
 static void init_cond_wait(struct cond_wait *w, unsigned int data);
diff --git a/drivers/tty/tty_io.c b/drivers/tty/tty_io.c
index 0c150b5a9dd6..974b13d24401 100644
--- a/drivers/tty/tty_io.c
+++ b/drivers/tty/tty_io.c
@@ -325,6 +325,56 @@ static struct tty_driver *get_tty_driver(dev_t device, int *index)
 	return NULL;
 }
 
+/**
+ *	tty_dev_name_to_number	-	return dev_t for device name
+ *	@name: user space name of device under /dev
+ *	@number: pointer to dev_t that this function will populate
+ *
+ *	This function converts device names like ttyS0 or ttyUSB1 into dev_t
+ *	like (4, 64) or (188, 1). If no corresponding driver is registered then
+ *	the function returns -ENODEV.
+ *
+ *	Locking: this acquires tty_mutex to protect the tty_drivers list from
+ *		being modified while we are traversing it, and makes sure to
+ *		release it before exiting.
+ */
+int tty_dev_name_to_number(const char *name, dev_t *number)
+{
+	struct tty_driver *p;
+	int ret;
+	int index, prefix_length = 0;
+	const char *str;
+
+	for (str = name; *str && !isdigit(*str); str++)
+		;
+
+	if (!*str)
+		return -EINVAL;
+
+	ret = kstrtoint(str, 10, &index);
+	if (ret)
+		return ret;
+
+	prefix_length = str - name;
+	mutex_lock(&tty_mutex);
+
+	list_for_each_entry(p, &tty_drivers, tty_drivers)
+		if (prefix_length == strlen(p->name) && strncmp(name,
+					p->name, prefix_length) == 0) {
+			if (index < p->num) {
+				*number = MKDEV(p->major, p->minor_start + index);
+				goto out;
+			}
+		}
+
+	/* if here then driver wasn't found */
+	ret = -ENODEV;
+out:
+	mutex_unlock(&tty_mutex);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(tty_dev_name_to_number);
+
 #ifdef CONFIG_CONSOLE_POLL
 
 /**
@@ -1083,7 +1133,10 @@ static struct tty_struct *tty_driver_lookup_tty(struct tty_driver *driver,
 	struct tty_struct *tty;
 
 	if (driver->ops->lookup)
-		tty = driver->ops->lookup(driver, file, idx);
+		if (!file)
+			tty = ERR_PTR(-EIO);
+		else
+			tty = driver->ops->lookup(driver, file, idx);
 	else
 		tty = driver->ttys[idx];
 
@@ -1715,7 +1768,7 @@ static struct tty_driver *tty_lookup_driver(dev_t device, struct file *filp,
 		struct tty_driver *console_driver = console_device(index);
 		if (console_driver) {
 			driver = tty_driver_kref_get(console_driver);
-			if (driver) {
+			if (driver && filp) {
 				/* Don't let /dev/console block */
 				filp->f_flags |= O_NONBLOCK;
 				break;
@@ -1748,7 +1801,7 @@ static struct tty_driver *tty_lookup_driver(dev_t device, struct file *filp,
  *	  - concurrent tty driver removal w/ lookup
  *	  - concurrent tty removal from driver table
  */
-static struct tty_struct *tty_open_by_driver(dev_t device, struct inode *inode,
+struct tty_struct *tty_open_by_driver(dev_t device, struct inode *inode,
 					     struct file *filp)
 {
 	struct tty_struct *tty;
@@ -1793,6 +1846,7 @@ out:
 	tty_driver_kref_put(driver);
 	return tty;
 }
+EXPORT_SYMBOL_GPL(tty_open_by_driver);
 
 /**
  *	tty_open		-	open a tty device
diff --git a/drivers/tty/tty_ldisc.c b/drivers/tty/tty_ldisc.c
index 4a04567d9aef..2fe216b276e2 100644
--- a/drivers/tty/tty_ldisc.c
+++ b/drivers/tty/tty_ldisc.c
@@ -621,6 +621,7 @@ err:
 	tty_unlock(tty);
 	return retval;
 }
+EXPORT_SYMBOL_GPL(tty_set_ldisc);
 
 /**
  *	tty_ldisc_kill	-	teardown ldisc
@@ -813,6 +814,7 @@ void tty_ldisc_release(struct tty_struct *tty)
 
 	tty_ldisc_debug(tty, "released\n");
 }
+EXPORT_SYMBOL_GPL(tty_ldisc_release);
 
 /**
  *	tty_ldisc_init		-	ldisc setup for new tty