diff -urN 2.4.15pre1/fs/namei.c atomic-lookup/fs/namei.c
--- 2.4.15pre1/fs/namei.c	Wed Oct 24 08:04:22 2001
+++ atomic-lookup/fs/namei.c	Fri Nov  9 04:34:12 2001
@@ -448,9 +448,13 @@
 {
 	struct dentry *dentry;
 	struct inode *inode;
-	int err;
+	int err, atomic;
 	unsigned int lookup_flags = nd->flags;
 
+	atomic = 0;
+	if (lookup_flags & LOOKUP_ATOMIC)
+		atomic = 1;
+
 	while (*name=='/')
 		name++;
 	if (!*name)
@@ -519,6 +523,9 @@
 		/* This does the actual lookups.. */
 		dentry = cached_lookup(nd->dentry, &this, LOOKUP_CONTINUE);
 		if (!dentry) {
+			err = -EWOULDBLOCKIO;
+			if (atomic)
+				break;
 			dentry = real_lookup(nd->dentry, &this, LOOKUP_CONTINUE);
 			err = PTR_ERR(dentry);
 			if (IS_ERR(dentry))
@@ -582,6 +589,9 @@
 		}
 		dentry = cached_lookup(nd->dentry, &this, 0);
 		if (!dentry) {
+			err = -EWOULDBLOCKIO;
+			if (atomic)
+				break;
 			dentry = real_lookup(nd->dentry, &this, 0);
 			err = PTR_ERR(dentry);
 			if (IS_ERR(dentry))
@@ -924,6 +934,8 @@
 	
 	if (f & O_DIRECTORY)
 		retval |= LOOKUP_DIRECTORY;
+	if (f & O_ATOMICLOOKUP)
+		retval |= LOOKUP_ATOMIC;
 
 	return retval;
 }
diff -urN 2.4.15pre1/include/asm-alpha/fcntl.h atomic-lookup/include/asm-alpha/fcntl.h
--- 2.4.15pre1/include/asm-alpha/fcntl.h	Sun Sep 23 21:11:40 2001
+++ atomic-lookup/include/asm-alpha/fcntl.h	Fri Nov  9 04:34:12 2001
@@ -20,6 +20,7 @@
 #define O_DIRECTORY	0100000	/* must be a directory */
 #define O_NOFOLLOW	0200000 /* don't follow links */
 #define O_LARGEFILE	0400000 /* will be set by the kernel on every open */
+#define O_ATOMICLOOKUP  01000000 /* do atomic file lookup */
 #define O_DIRECT	02000000 /* direct disk access - should check with OSF/1 */
 
 #define F_DUPFD		0	/* dup */
diff -urN 2.4.15pre1/include/asm-i386/fcntl.h atomic-lookup/include/asm-i386/fcntl.h
--- 2.4.15pre1/include/asm-i386/fcntl.h	Sun Sep 23 21:11:40 2001
+++ atomic-lookup/include/asm-i386/fcntl.h	Fri Nov  9 04:34:12 2001
@@ -20,6 +20,7 @@
 #define O_LARGEFILE	0100000
 #define O_DIRECTORY	0200000	/* must be a directory */
 #define O_NOFOLLOW	0400000 /* don't follow links */
+#define O_ATOMICLOOKUP	01000000 /* do atomic file lookup */
 
 #define F_DUPFD		0	/* dup */
 #define F_GETFD		1	/* get close_on_exec */
diff -urN 2.4.15pre1/include/asm-ia64/fcntl.h atomic-lookup/include/asm-ia64/fcntl.h
--- 2.4.15pre1/include/asm-ia64/fcntl.h	Thu Nov 16 15:37:42 2000
+++ atomic-lookup/include/asm-ia64/fcntl.h	Fri Nov  9 04:34:12 2001
@@ -28,6 +28,7 @@
 #define O_LARGEFILE	0100000
 #define O_DIRECTORY	0200000	/* must be a directory */
 #define O_NOFOLLOW	0400000 /* don't follow links */
+#define O_ATOMICLOOKUP  01000000 /* do atomic file lookup */
 
 #define F_DUPFD		0	/* dup */
 #define F_GETFD		1	/* get close_on_exec */
diff -urN 2.4.15pre1/include/asm-ppc/fcntl.h atomic-lookup/include/asm-ppc/fcntl.h
--- 2.4.15pre1/include/asm-ppc/fcntl.h	Tue Nov  6 02:04:53 2001
+++ atomic-lookup/include/asm-ppc/fcntl.h	Fri Nov  9 04:34:42 2001
@@ -23,6 +23,7 @@
 #define O_NOFOLLOW      0100000	/* don't follow links */
 #define O_LARGEFILE     0200000
 #define O_DIRECT	0400000	/* direct disk access hint */
+#define O_ATOMICLOOKUP 01000000 /* do atomic file lookup */
 
 #define F_DUPFD		0	/* dup */
 #define F_GETFD		1	/* get close_on_exec */
diff -urN 2.4.15pre1/include/asm-sparc/fcntl.h atomic-lookup/include/asm-sparc/fcntl.h
--- 2.4.15pre1/include/asm-sparc/fcntl.h	Sun Sep 23 21:11:42 2001
+++ atomic-lookup/include/asm-sparc/fcntl.h	Fri Nov  9 04:34:12 2001
@@ -20,6 +20,7 @@
 #define O_DIRECTORY	0x10000	/* must be a directory */
 #define O_NOFOLLOW	0x20000	/* don't follow links */
 #define O_LARGEFILE	0x40000
+#define O_ATOMICLOOKUP  0x80000 /* do atomic file lookup */
 #define O_DIRECT        0x100000 /* direct disk access hint */
 
 #define F_DUPFD		0	/* dup */
diff -urN 2.4.15pre1/include/asm-sparc64/fcntl.h atomic-lookup/include/asm-sparc64/fcntl.h
--- 2.4.15pre1/include/asm-sparc64/fcntl.h	Sun Sep 23 21:11:42 2001
+++ atomic-lookup/include/asm-sparc64/fcntl.h	Fri Nov  9 04:34:12 2001
@@ -20,6 +20,7 @@
 #define O_DIRECTORY	0x10000	/* must be a directory */
 #define O_NOFOLLOW	0x20000	/* don't follow links */
 #define O_LARGEFILE	0x40000
+#define O_ATOMICLOOKUP  0x80000 /* do atomic file lookup */
 #define O_DIRECT        0x100000 /* direct disk access hint */
 
 
diff -urN 2.4.15pre1/include/linux/errno.h atomic-lookup/include/linux/errno.h
--- 2.4.15pre1/include/linux/errno.h	Fri Aug 17 05:02:27 2001
+++ atomic-lookup/include/linux/errno.h	Fri Nov  9 04:34:12 2001
@@ -21,6 +21,9 @@
 #define EBADTYPE	527	/* Type not supported by server */
 #define EJUKEBOX	528	/* Request initiated, but will not complete before timeout */
 
+/* Defined for TUX async IO */
+#define EWOULDBLOCKIO	530	/* Would block due to block-IO */
+
 #endif
 
 #endif
diff -urN 2.4.15pre1/include/linux/fs.h atomic-lookup/include/linux/fs.h
--- 2.4.15pre1/include/linux/fs.h	Tue Nov  6 02:04:53 2001
+++ atomic-lookup/include/linux/fs.h	Fri Nov  9 04:34:12 2001
@@ -1260,6 +1260,7 @@
 #define LOOKUP_POSITIVE		(8)
 #define LOOKUP_PARENT		(16)
 #define LOOKUP_NOALT		(32)
+#define LOOKUP_ATOMIC		(64)
 /*
  * Type of the last component on LOOKUP_PARENT
  */
diff -urNX /suse/olh/kernel_exclude.txt linux-2.4.19.orig/include/asm-ppc64/fcntl.h linux-2.4.19/include/asm-ppc64/fcntl.h
--- linux-2.4.19.orig/include/asm-ppc64/fcntl.h	2002-09-15 15:08:30.000000000 +0200
+++ linux-2.4.19/include/asm-ppc64/fcntl.h	2002-09-15 15:19:32.000000000 +0200
@@ -27,6 +27,7 @@
 #define O_NOFOLLOW      0100000	/* don't follow links */
 #define O_LARGEFILE     0200000
 #define O_DIRECT	0400000	/* direct disk access hint */
+#define O_ATOMICLOOKUP 01000000 /* do atomic file lookup */
 
 #define F_DUPFD		0	/* dup */
 #define F_GETFD		1	/* get close_on_exec */