+ radix-tree-move-declarations-to-header.patch added to mm-hotfixes-unstable branch

+ radix-tree-move-declarations-to-header.patch added to mm-hotfixes-unstable branch

[Andrew Morton]

The patch titled
     Subject: radix-tree: move declarations to header
has been added to the -mm mm-hotfixes-unstable branch.  Its filename is
     radix-tree-move-declarations-to-header.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/radix-tree-move-declarations-to-header.patch

This patch will later appear in the mm-hotfixes-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------
From: Arnd Bergmann <arnd@arndb.de>
Subject: radix-tree: move declarations to header
Date: Tue, 16 May 2023 21:41:54 +0200

The xarray.c file contains the only call to radix_tree_node_rcu_free(),
and it comes with its own extern declaration for it.  This means the
function definition causes a missing-prototype warning:

lib/radix-tree.c:288:6: error: no previous prototype for 'radix_tree_node_rcu_free' [-Werror=missing-prototypes]

Instead, move the declaration for this function to a new header that can
be included by both, and do the same for the radix_tree_node_cachep
variable that has the same underlying problem but does not cause a warning
with gcc.

Link: https://lkml.kernel.org/r/20230516194212.548910-1-arnd@kernel.org
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 lib/radix-tree.c |    2 ++
 lib/radix-tree.h |    8 ++++++++
 lib/xarray.c     |    6 ++----
 3 files changed, 12 insertions(+), 4 deletions(-)

--- a/lib/radix-tree.c~radix-tree-move-declarations-to-header
+++ a/lib/radix-tree.c
@@ -27,6 +27,8 @@
 #include <linux/string.h>
 #include <linux/xarray.h>
 
+#include "radix-tree.h"
+
 /*
  * Radix tree node cache.
  */
--- /dev/null
+++ a/lib/radix-tree.h
@@ -0,0 +1,8 @@
+// SPDX-License-Identifier: GPL-2.0+
+/* radix-tree helpers that are only shared with xarray */
+
+struct kmem_cache;
+struct rcu_head;
+
+extern struct kmem_cache *radix_tree_node_cachep;
+extern void radix_tree_node_rcu_free(struct rcu_head *head);
--- a/lib/xarray.c~radix-tree-move-declarations-to-header
+++ a/lib/xarray.c
@@ -12,6 +12,8 @@
 #include <linux/slab.h>
 #include <linux/xarray.h>
 
+#include "radix-tree.h"
+
 /*
  * Coding conventions in this file:
  *
@@ -247,10 +249,6 @@ void *xas_load(struct xa_state *xas)
 }
 EXPORT_SYMBOL_GPL(xas_load);
 
-/* Move the radix tree node cache here */
-extern struct kmem_cache *radix_tree_node_cachep;
-extern void radix_tree_node_rcu_free(struct rcu_head *head);
-
 #define XA_RCU_FREE	((struct xarray *)1)
 
 static void xa_node_free(struct xa_node *node)
_

Patches currently in -mm which might be from arnd@arndb.de are

radix-tree-move-declarations-to-header.patch
kasan-add-kasan_tag_mismatch-prototype.patch
kasan-use-internal-prototypes-matching-gcc-13-builtins.patch