[PATCH 21/24] TTY: centralize fail paths in tty_register_driver

From: Jiri Slaby
Date: Mon Jun 04 2012 - 07:41:31 EST


Currently, some failures are handled in if's false branches, some at
the end of tty_register_driver via goto-labels. Let us handle the
failures at the end of the functions to have the failure handling at
a single place. The only thing needed is to label the lines properly
and jump there.

Signed-off-by: Jiri Slaby <jslaby@xxxxxxx>
---
drivers/tty/tty_io.c | 18 ++++++------------
1 file changed, 6 insertions(+), 12 deletions(-)

diff --git a/drivers/tty/tty_io.c b/drivers/tty/tty_io.c
index b425c79..d6e045b 100644
--- a/drivers/tty/tty_io.c
+++ b/drivers/tty/tty_io.c
@@ -3144,10 +3144,8 @@ int tty_register_driver(struct tty_driver *driver)
dev = MKDEV(driver->major, driver->minor_start);
error = register_chrdev_region(dev, driver->num, driver->name);
}
- if (error < 0) {
- kfree(p);
- return error;
- }
+ if (error < 0)
+ goto err_free_p;

if (p) {
driver->ttys = (struct tty_struct **)p;
@@ -3160,13 +3158,8 @@ int tty_register_driver(struct tty_driver *driver)
cdev_init(&driver->cdev, &tty_fops);
driver->cdev.owner = driver->owner;
error = cdev_add(&driver->cdev, dev, driver->num);
- if (error) {
- unregister_chrdev_region(dev, driver->num);
- driver->ttys = NULL;
- driver->termios = NULL;
- kfree(p);
- return error;
- }
+ if (error)
+ goto err_unreg_char;

mutex_lock(&tty_mutex);
list_add(&driver->tty_drivers, &tty_drivers);
@@ -3193,13 +3186,14 @@ err:
list_del(&driver->tty_drivers);
mutex_unlock(&tty_mutex);

+err_unreg_char:
unregister_chrdev_region(dev, driver->num);
driver->ttys = NULL;
driver->termios = NULL;
+err_free_p:
kfree(p);
return error;
}
-
EXPORT_SYMBOL(tty_register_driver);

/*
--
1.7.10.3


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