cosa: cdev lock_kernel() pushdown
authorJonathan Corbet <corbet@lwn.net>
Thu, 15 May 2008 15:21:33 +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/net/wan/cosa.c

index b0fce1387eaf2555a3d43fe89ccabf801d2a9891..5827324e9d9f94a2abde26a450c1b4be90c941cf 100644 (file)
@@ -92,6 +92,7 @@
 #include <linux/spinlock.h>
 #include <linux/mutex.h>
 #include <linux/device.h>
+#include <linux/smp_lock.h>
 
 #undef COSA_SLOW_IO    /* for testing purposes only */
 
@@ -970,15 +971,21 @@ static int cosa_open(struct inode *inode, struct file *file)
        struct channel_data *chan;
        unsigned long flags;
        int n;
+       int ret = 0;
 
+       lock_kernel();
        if ((n=iminor(file->f_path.dentry->d_inode)>>CARD_MINOR_BITS)
-               >= nr_cards)
-               return -ENODEV;
+               >= nr_cards) {
+               ret = -ENODEV;
+               goto out;
+       }
        cosa = cosa_cards+n;
 
        if ((n=iminor(file->f_path.dentry->d_inode)
-               & ((1<<CARD_MINOR_BITS)-1)) >= cosa->nchannels)
-               return -ENODEV;
+               & ((1<<CARD_MINOR_BITS)-1)) >= cosa->nchannels) {
+               ret = -ENODEV;
+               goto out;
+       }
        chan = cosa->chan + n;
        
        file->private_data = chan;
@@ -987,7 +994,8 @@ static int cosa_open(struct inode *inode, struct file *file)
 
        if (chan->usage < 0) { /* in netdev mode */
                spin_unlock_irqrestore(&cosa->lock, flags);
-               return -EBUSY;
+               ret = -EBUSY;
+               goto out;
        }
        cosa->usage++;
        chan->usage++;
@@ -996,7 +1004,9 @@ static int cosa_open(struct inode *inode, struct file *file)
        chan->setup_rx = chrdev_setup_rx;
        chan->rx_done = chrdev_rx_done;
        spin_unlock_irqrestore(&cosa->lock, flags);
-       return 0;
+out:
+       unlock_kernel();
+       return ret;
 }
 
 static int cosa_release(struct inode *inode, struct file *file)