--- ./drmP.h.orig	Sat Mar  9 01:39:07 2002
+++ ./drmP.h	Sat Mar  9 01:45:53 2002
@@ -32,6 +32,41 @@
 #ifndef _DRM_P_H_
 #define _DRM_P_H_
 
+#include <linux/bitops.h> /* for LOCK_PREFIX */
+#include <asm/system.h> /* for LOCK_PREFIX */
+#ifdef __i386__
+static inline unsigned long __cmpxchg(volatile void *ptr, unsigned long old,
+                                      unsigned long new, int size)
+{
+        unsigned long prev;
+        switch (size) {
+        case 1:
+                __asm__ __volatile__(LOCK_PREFIX "cmpxchgb %b1,%2"
+                                     : "=a"(prev)
+                                     : "q"(new), "m"(*__xg(ptr)), "0"(old)
+                                     : "memory");
+                return prev;
+        case 2:
+                __asm__ __volatile__(LOCK_PREFIX "cmpxchgw %w1,%2"
+                                     : "=a"(prev)
+                                     : "q"(new), "m"(*__xg(ptr)), "0"(old)
+                                     : "memory");
+                return prev;
+        case 4:
+                __asm__ __volatile__(LOCK_PREFIX "cmpxchgl %1,%2"
+                                     : "=a"(prev)
+                                     : "q"(new), "m"(*__xg(ptr)), "0"(old)
+                                     : "memory");
+                return prev;
+        }
+        return old;
+}
+
+#define cmpxchg(ptr,o,n)                                                \
+  ((__typeof__(*(ptr)))__cmpxchg((ptr),(unsigned long)(o),              \
+                                 (unsigned long)(n),sizeof(*(ptr))))
+#endif /* i386 */
+
 #ifdef __KERNEL__
 #ifdef __alpha__
 /* add include of current.h so that "current" is defined