i2c: cdev lock_kernel() pushdown
authorJonathan Corbet <corbet@lwn.net>
Thu, 15 May 2008 15:21:02 +0000 (09:21 -0600)
committerJonathan Corbet <corbet@lwn.net>
Sun, 18 May 2008 21:43:40 +0000 (15:43 -0600)
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
drivers/i2c/i2c-dev.c

index d34c14c81c291e9beabf7100530307b8a42e8914..006a5857256a15b9cebab931d5c9489a62ed891d 100644 (file)
@@ -34,6 +34,7 @@
 #include <linux/list.h>
 #include <linux/i2c.h>
 #include <linux/i2c-dev.h>
+#include <linux/smp_lock.h>
 #include <asm/uaccess.h>
 
 static struct i2c_driver i2cdev_driver;
@@ -441,14 +442,20 @@ 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)
-               return -ENODEV;
+       if (!i2c_dev) {
+               ret = -ENODEV;
+               goto out;
+       }
 
        adap = i2c_get_adapter(i2c_dev->adap->nr);
-       if (!adap)
-               return -ENODEV;
+       if (!adap) {
+               ret = -ENODEV;
+               goto out;
+       }
 
        /* This creates an anonymous i2c_client, which may later be
         * pointed to some address using I2C_SLAVE or I2C_SLAVE_FORCE.
@@ -460,7 +467,8 @@ static int i2cdev_open(struct inode *inode, struct file *file)
        client = kzalloc(sizeof(*client), GFP_KERNEL);
        if (!client) {
                i2c_put_adapter(adap);
-               return -ENOMEM;
+               ret = -ENOMEM;
+               goto out;
        }
        snprintf(client->name, I2C_NAME_SIZE, "i2c-dev %d", adap->nr);
        client->driver = &i2cdev_driver;
@@ -468,7 +476,9 @@ static int i2cdev_open(struct inode *inode, struct file *file)
        client->adapter = adap;
        file->private_data = client;
 
-       return 0;
+out:
+       unlock_kernel();
+       return ret;
 }
 
 static int i2cdev_release(struct inode *inode, struct file *file)