idr: deprecate idr_remove_all()

There was only one legitimate use of idr_remove_all() and a lot more of
incorrect uses (or lack of it).  Now that idr_destroy() implies
idr_remove_all() and all the in-kernel users updated not to use it,
there's no reason to keep it around.  Mark it deprecated so that we can
later unexport it.

idr_remove_all() is made an inline function calling __idr_remove_all()
to avoid triggering deprecated warning on EXPORT_SYMBOL().

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/lib/idr.c b/lib/idr.c
index b8602e0..814c53c 100644
--- a/lib/idr.c
+++ b/lib/idr.c
@@ -433,11 +433,7 @@
 }
 EXPORT_SYMBOL(idr_remove);
 
-/**
- * idr_remove_all - remove all ids from the given idr tree
- * @idp: idr handle
- */
-void idr_remove_all(struct idr *idp)
+void __idr_remove_all(struct idr *idp)
 {
 	int n, id, max;
 	int bt_mask;
@@ -470,7 +466,7 @@
 	}
 	idp->layers = 0;
 }
-EXPORT_SYMBOL(idr_remove_all);
+EXPORT_SYMBOL(__idr_remove_all);
 
 /**
  * idr_destroy - release all cached layers within an idr tree
@@ -487,7 +483,7 @@
  */
 void idr_destroy(struct idr *idp)
 {
-	idr_remove_all(idp);
+	__idr_remove_all(idp);
 
 	while (idp->id_free_cnt) {
 		struct idr_layer *p = get_from_free_list(idp);