nvram: BKL pushdown

Signed-off-by: Arnd Bergmann <arnd@arndb.de>

drivers/char/nvram.c

@@ -107,6 +107,7 @@
 #include <linux/init.h>
 #include <linux/proc_fs.h>
 #include <linux/spinlock.h>
+#include <linux/smp_lock.h>
 
 #include <asm/io.h>
 #include <asm/uaccess.h>
@@ -333,12 +334,14 @@ nvram_ioctl(struct inode *inode, struct file *file,
 static int
 nvram_open(struct inode *inode, struct file *file)
 {
+	lock_kernel();
 	spin_lock(&nvram_state_lock);
 
 	if ((nvram_open_cnt && (file->f_flags & O_EXCL)) ||
 	    (nvram_open_mode & NVRAM_EXCL) ||
 	    ((file->f_mode & 2) && (nvram_open_mode & NVRAM_WRITE))) {
 		spin_unlock(&nvram_state_lock);
+		unlock_kernel();
 		return -EBUSY;
 	}
 
@@ -349,6 +352,7 @@ nvram_open(struct inode *inode, struct file *file)
 	nvram_open_cnt++;
 
 	spin_unlock(&nvram_state_lock);
+	unlock_kernel();
 
 	return 0;
 }