vfs: Add 64 bit i_version support
The i_version field of the inode is changed to be a 64-bit counter that
is set on every 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.
This first part concerns the vfs, it converts the 32-bit i_version in
the generic inode to a 64-bit, a flag is added in the super block in
order to check if the feature is enabled and the i_version is
incremented in the vfs.
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: Jean Noel Cordenner <jean-noel.cordenner@bull.net>
Signed-off-by: Kalpak Shah <kalpak@clusterfs.com>
diff --git a/fs/inode.c b/fs/inode.c
index ed35383..b48324a 100644
--- a/fs/inode.c
+++ b/fs/inode.c
@@ -1243,6 +1243,23 @@
EXPORT_SYMBOL(touch_atime);
/**
+ * inode_inc_iversion - increments i_version
+ * @inode: inode that need to be updated
+ *
+ * Every time the inode is modified, the i_version field
+ * will be incremented.
+ * The filesystem has to be mounted with i_version flag
+ *
+ */
+
+void inode_inc_iversion(struct inode *inode)
+{
+ spin_lock(&inode->i_lock);
+ inode->i_version++;
+ spin_unlock(&inode->i_lock);
+}
+
+/**
* file_update_time - update mtime and ctime time
* @file: file accessed
*
@@ -1276,6 +1293,11 @@
sync_it = 1;
}
+ if (IS_I_VERSION(inode)) {
+ inode_inc_iversion(inode);
+ sync_it = 1;
+ }
+
if (sync_it)
mark_inode_dirty_sync(inode);
}