The patch modifies the i_version field of the inode on the VFS layer.
The i_version field become a 64bit counter that is set on inode creation and
that is incremented every time the inode data is modified (similarly to the
"ctime" time-stamp).
The aim is to fulfill a NFSv4 requirement for rfc3530:
"5.5.  Mandatory Attributes - Definitions
Name		#	DataType   Access   Description
___________________________________________________________________
change		3	uint64       READ     A value created by the
		server that the client can use to determine if file
		data, directory contents or attributes of the object
		have been modified.  The servermay return the object's
		time_metadata attribute for this attribute's value but
		only if the filesystem object can not be updated more
		frequently than the resolution of time_metadata."

Signed-off-by: Jean Noel Cordenner <jean-noel.cordenner@bull.net>

Index: linux-2.6.22-rc4/fs/binfmt_misc.c
===================================================================
--- linux-2.6.22-rc4.orig/fs/binfmt_misc.c	2007-06-04 17:57:25.000000000 -0700
+++ linux-2.6.22-rc4/fs/binfmt_misc.c	2007-06-13 17:24:57.000000000 -0700
@@ -508,6 +508,7 @@ static struct inode *bm_get_inode(struct
 		inode->i_blocks = 0;
 		inode->i_atime = inode->i_mtime = inode->i_ctime =
 			current_fs_time(inode->i_sb);
+		inode->i_version = 1;
 	}
 	return inode;
 }
Index: linux-2.6.22-rc4/fs/libfs.c
===================================================================
--- linux-2.6.22-rc4.orig/fs/libfs.c	2007-06-04 17:57:25.000000000 -0700
+++ linux-2.6.22-rc4/fs/libfs.c	2007-06-13 17:24:57.000000000 -0700
@@ -232,6 +232,7 @@ int get_sb_pseudo(struct file_system_typ
 	root->i_mode = S_IFDIR | S_IRUSR | S_IWUSR;
 	root->i_uid = root->i_gid = 0;
 	root->i_atime = root->i_mtime = root->i_ctime = CURRENT_TIME;
+	root->i_version = 1;
 	dentry = d_alloc(NULL, &d_name);
 	if (!dentry) {
 		iput(root);
@@ -255,6 +256,8 @@ int simple_link(struct dentry *old_dentr
 	struct inode *inode = old_dentry->d_inode;
 
 	inode->i_ctime = dir->i_ctime = dir->i_mtime = CURRENT_TIME;
+	inode->i_version++;
+	dir->i_version++;
 	inc_nlink(inode);
 	atomic_inc(&inode->i_count);
 	dget(dentry);
@@ -287,6 +290,8 @@ int simple_unlink(struct inode *dir, str
 	struct inode *inode = dentry->d_inode;
 
 	inode->i_ctime = dir->i_ctime = dir->i_mtime = CURRENT_TIME;
+	inode->i_version++;
+	dir->i_version++;
 	drop_nlink(inode);
 	dput(dentry);
 	return 0;
@@ -323,6 +328,8 @@ int simple_rename(struct inode *old_dir,
 
 	old_dir->i_ctime = old_dir->i_mtime = new_dir->i_ctime =
 		new_dir->i_mtime = inode->i_ctime = CURRENT_TIME;
+	old_dir->i_version++;
+	new_dir->i_version++;
 
 	return 0;
 }
@@ -399,6 +406,7 @@ int simple_fill_super(struct super_block
 	inode->i_uid = inode->i_gid = 0;
 	inode->i_blocks = 0;
 	inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
+	inode->i_version = 1;
 	inode->i_op = &simple_dir_inode_operations;
 	inode->i_fop = &simple_dir_operations;
 	inode->i_nlink = 2;
@@ -427,6 +435,7 @@ int simple_fill_super(struct super_block
 		inode->i_uid = inode->i_gid = 0;
 		inode->i_blocks = 0;
 		inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
+		inode->i_version = 1;
 		inode->i_fop = files->ops;
 		inode->i_ino = i;
 		d_add(dentry, inode);
Index: linux-2.6.22-rc4/fs/pipe.c
===================================================================
--- linux-2.6.22-rc4.orig/fs/pipe.c	2007-06-04 17:57:25.000000000 -0700
+++ linux-2.6.22-rc4/fs/pipe.c	2007-06-13 17:24:57.000000000 -0700
@@ -882,6 +882,7 @@ static struct inode * get_pipe_inode(voi
 	inode->i_uid = current->fsuid;
 	inode->i_gid = current->fsgid;
 	inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
+	inode->i_version = 1;
 
 	return inode;