From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1762004AbZJJQoN (ORCPT ); Sat, 10 Oct 2009 12:44:13 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753692AbZJJQoM (ORCPT ); Sat, 10 Oct 2009 12:44:12 -0400 Received: from flounder.pepperfish.net ([87.237.62.181]:42707 "EHLO flounder.pepperfish.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753228AbZJJQoM (ORCPT ); Sat, 10 Oct 2009 12:44:12 -0400 From: Vincent Sanders To: linux-kernel@vger.kernel.org Cc: tglx@linutronix.de, Vincent Sanders Subject: [PATCH] Remove big kernel lock use from i2cdev_open Date: Sat, 10 Oct 2009 12:46:12 +0100 Message-Id: <1255175172-2666-1-git-send-email-vince@simtec.co.uk> X-Mailer: git-send-email 1.6.0.4 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The BKL is held over a kmalloc so cannot protect anything beyond that. The two calls before the kmalloc have their own locking. Improve device open function by removing the now unnecessary ret variable Signed-off-by: Vincent Sanders --- drivers/i2c/i2c-dev.c | 21 ++++++--------------- 1 files changed, 6 insertions(+), 15 deletions(-) diff --git a/drivers/i2c/i2c-dev.c b/drivers/i2c/i2c-dev.c index 7e13d2d..3196503 100644 --- a/drivers/i2c/i2c-dev.c +++ b/drivers/i2c/i2c-dev.c @@ -445,20 +445,14 @@ static int i2cdev_open(struct inode *inode, struct file *file) struct i2c_client *client; struct i2c_adapter *adap; struct i2c_dev *i2c_dev; - int ret = 0; - lock_kernel(); i2c_dev = i2c_dev_get_by_minor(minor); - if (!i2c_dev) { - ret = -ENODEV; - goto out; - } + if (!i2c_dev) + return -ENODEV; adap = i2c_get_adapter(i2c_dev->adap->nr); - if (!adap) { - ret = -ENODEV; - goto out; - } + if (!adap) + return -ENODEV; /* This creates an anonymous i2c_client, which may later be * pointed to some address using I2C_SLAVE or I2C_SLAVE_FORCE. @@ -470,8 +464,7 @@ static int i2cdev_open(struct inode *inode, struct file *file) client = kzalloc(sizeof(*client), GFP_KERNEL); if (!client) { i2c_put_adapter(adap); - ret = -ENOMEM; - goto out; + return -ENOMEM; } snprintf(client->name, I2C_NAME_SIZE, "i2c-dev %d", adap->nr); client->driver = &i2cdev_driver; @@ -479,9 +472,7 @@ static int i2cdev_open(struct inode *inode, struct file *file) client->adapter = adap; file->private_data = client; -out: - unlock_kernel(); - return ret; + return 0; } static int i2cdev_release(struct inode *inode, struct file *file) -- 1.6.0.4