#include <linux/workqueue.h>
 #include <linux/sunrpc/rpc_pipe_fs.h>
 #include <linux/sunrpc/cache.h>
+#include <linux/smp_lock.h>
 
 static struct vfsmount *rpc_mount __read_mostly;
 static int rpc_mount_count;
 }
 
 static int
-rpc_pipe_ioctl(struct inode *ino, struct file *filp,
-               unsigned int cmd, unsigned long arg)
+rpc_pipe_ioctl_unlocked(struct file *filp, unsigned int cmd, unsigned long arg)
 {
        struct rpc_inode *rpci = RPC_I(filp->f_path.dentry->d_inode);
        int len;
        }
 }
 
+static long
+rpc_pipe_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
+{
+       long ret;
+
+       lock_kernel();
+       ret = rpc_pipe_ioctl_unlocked(filp, cmd, arg);
+       unlock_kernel();
+
+       return ret;
+}
+
 static const struct file_operations rpc_pipe_fops = {
        .owner          = THIS_MODULE,
        .llseek         = no_llseek,
        .read           = rpc_pipe_read,
        .write          = rpc_pipe_write,
        .poll           = rpc_pipe_poll,
-       .ioctl          = rpc_pipe_ioctl,
+       .unlocked_ioctl = rpc_pipe_ioctl,
        .open           = rpc_pipe_open,
        .release        = rpc_pipe_release,
 };