- * Update the mtime time on an inode and mark it for writeback.
- * When ctime_too is specified update the ctime too.
+ * Update the mtime and ctime members of an inode and mark the inode
+ * for writeback. Note that this function is meant exclusively for
+ * usage in the file write path of filesystems, and filesystems may
+ * choose to explicitly ignore update via this function with the
+ * S_NOCTIME inode flag, e.g. for network filesystem where these
+ * timestamps are handled by the server.