SLES10 Fixes (part 3):

- Configure check for mutex_lock_nested().  This function was introduced
  as part of the mutex validator in 2.6.18, but if it's unavailable then
  it's safe to fallback to a plain mutex_lock().

include/linux/mutex_compat.h

@@ -0,0 +1,12 @@
+#ifndef _SPL_MUTEX_COMPAT_H
+#define _SPL_MUTEX_COMPAT_H
+
+#include <linux/mutex.h>
+
+/* mutex_lock_nested() introduced in 2.6.18 */
+#ifndef HAVE_MUTEX_LOCK_NESTED
+# define mutex_lock_nested(lock, subclass)	mutex_lock(lock)
+#endif /* HAVE_MUTEX_LOCK_NESTED */
+
+#endif /* _SPL_MUTEX_COMPAT_H */
+

include/sys/types.h

@@ -17,6 +17,7 @@ extern "C" {
 #include <linux/smp_compat.h>
 #include <linux/workqueue_compat.h>
 #include <linux/kallsyms_compat.h>
+#include <linux/mutex_compat.h>
 
 #ifndef HAVE_UINTPTR_T
 typedef unsigned long			uintptr_t;