diff --git a/include/linux/proc_fs.h b/include/linux/proc_fs.h
index 3469f96..28e3664 100644
--- a/include/linux/proc_fs.h
+++ b/include/linux/proc_fs.h
@@ -7,6 +7,8 @@
 #include <linux/magic.h>
 #include <asm/atomic.h>
 
+struct completion;
+
 /*
  * The proc filesystem constants/structures
  */
@@ -56,6 +58,14 @@
 	gid_t gid;
 	loff_t size;
 	const struct inode_operations *proc_iops;
+	/*
+	 * NULL ->proc_fops means "PDE is going away RSN" or
+	 * "PDE is just created". In either case, e.g. ->read_proc won't be
+	 * called because it's too late or too early, respectively.
+	 *
+	 * If you're allocating ->proc_fops dynamically, save a pointer
+	 * somewhere.
+	 */
 	const struct file_operations *proc_fops;
 	get_info_t *get_info;
 	struct module *owner;
@@ -66,6 +76,9 @@
 	atomic_t count;		/* use count */
 	int deleted;		/* delete flag */
 	void *set;
+	int pde_users;	/* number of callers into module in progress */
+	spinlock_t pde_unload_lock; /* proc_fops checks and pde_users bumps */
+	struct completion *pde_unload_completion;
 };
 
 struct kcore_list {