Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/j.anaszewski...

[linux-2.6-block.git] / drivers / mailbox / mailbox-test.c

diff --git a/drivers/mailbox/mailbox-test.c b/drivers/mailbox/mailbox-test.c
index dc11bbf27274380ecf60b55491193363d947e5c0..58d04726cdd7dc13f0faad15aeec89214ffce620 100644 (file)
--- a/drivers/mailbox/mailbox-test.c
+++ b/drivers/mailbox/mailbox-test.c
@@ -46,7 +46,6 @@ static ssize_t mbox_test_signal_write(struct file *filp,
                                       size_t count, loff_t *ppos)
 {
        struct mbox_test_device *tdev = filp->private_data;
-       int ret;
 
        if (!tdev->tx_channel) {
                dev_err(tdev->dev, "Channel cannot do Tx\n");
@@ -60,17 +59,20 @@ static ssize_t mbox_test_signal_write(struct file *filp,
                return -EINVAL;
        }
 
-       tdev->signal = kzalloc(MBOX_MAX_SIG_LEN, GFP_KERNEL);
-       if (!tdev->signal)
-               return -ENOMEM;
+       /* Only allocate memory if we need to */
+       if (!tdev->signal) {
+               tdev->signal = kzalloc(MBOX_MAX_SIG_LEN, GFP_KERNEL);
+               if (!tdev->signal)
+                       return -ENOMEM;
+       }
 
-       ret = copy_from_user(tdev->signal, userbuf, count);
-       if (ret) {
+       if (copy_from_user(tdev->signal, userbuf, count)) {
                kfree(tdev->signal);
+               tdev->signal = NULL;
                return -EFAULT;
        }
 
-       return ret < 0 ? ret : count;
+       return count;
 }
 
 static const struct file_operations mbox_test_signal_ops = {