From 842382c368ddd1a00e878cb847c3272307aca9eb Mon Sep 17 00:00:00 2001
From: Frank van der Linden <fvdl@google.com>
Date: Fri, 28 Feb 2025 18:29:10 +0000
Subject: [PATCH] mm/bootmem_info: export register_page_bootmem_memmap

If other mm code wants to use this function for early memmap inialization
(on the platforms that have it), it should be made available properly, not
just unconditionally in mm.h

Make this function available for such cases.

Link: https://lkml.kernel.org/r/20250228182928.2645936-10-fvdl@google.com
Signed-off-by: Frank van der Linden <fvdl@google.com>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Dan Carpenter <dan.carpenter@linaro.org>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Joao Martins <joao.m.martins@oracle.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Madhavan Srinivasan <maddy@linux.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Roman Gushchin (Cruise) <roman.gushchin@linux.dev>
Cc: Usama Arif <usamaarif642@gmail.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Yu Zhao <yuzhao@google.com>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---
 arch/powerpc/mm/init_64.c    | 4 ++++
 include/linux/bootmem_info.h | 7 +++++++
 include/linux/mm.h           | 3 ---
 3 files changed, 11 insertions(+), 3 deletions(-)

diff --git a/arch/powerpc/mm/init_64.c b/arch/powerpc/mm/init_64.c
index d96bbc001e73..b6f3ae03ca9e 100644
--- a/arch/powerpc/mm/init_64.c
+++ b/arch/powerpc/mm/init_64.c
@@ -41,6 +41,7 @@
 #include <linux/libfdt.h>
 #include <linux/memremap.h>
 #include <linux/memory.h>
+#include <linux/bootmem_info.h>
 
 #include <asm/pgalloc.h>
 #include <asm/page.h>
@@ -386,10 +387,13 @@ void __ref vmemmap_free(unsigned long start, unsigned long end,
 }
 
 #endif
+
+#ifdef CONFIG_HAVE_BOOTMEM_INFO_NODE
 void register_page_bootmem_memmap(unsigned long section_nr,
 				  struct page *start_page, unsigned long size)
 {
 }
+#endif /* CONFIG_HAVE_BOOTMEM_INFO_NODE */
 
 #endif /* CONFIG_SPARSEMEM_VMEMMAP */
 
diff --git a/include/linux/bootmem_info.h b/include/linux/bootmem_info.h
index d8a8d245824a..4c506e76a808 100644
--- a/include/linux/bootmem_info.h
+++ b/include/linux/bootmem_info.h
@@ -18,6 +18,8 @@ enum bootmem_type {
 
 #ifdef CONFIG_HAVE_BOOTMEM_INFO_NODE
 void __init register_page_bootmem_info_node(struct pglist_data *pgdat);
+void register_page_bootmem_memmap(unsigned long section_nr, struct page *map,
+				  unsigned long nr_pages);
 
 void get_page_bootmem(unsigned long info, struct page *page,
 		enum bootmem_type type);
@@ -58,6 +60,11 @@ static inline void register_page_bootmem_info_node(struct pglist_data *pgdat)
 {
 }
 
+static inline void register_page_bootmem_memmap(unsigned long section_nr,
+		struct page *map, unsigned long nr_pages)
+{
+}
+
 static inline void put_page_bootmem(struct page *page)
 {
 }
diff --git a/include/linux/mm.h b/include/linux/mm.h
index 7b21b48627b0..cd4c9068c131 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -3998,9 +3998,6 @@ static inline bool vmemmap_can_optimize(struct vmem_altmap *altmap,
 }
 #endif
 
-void register_page_bootmem_memmap(unsigned long section_nr, struct page *map,
-				  unsigned long nr_pages);
-
 enum mf_flags {
 	MF_COUNT_INCREASED = 1 << 0,
 	MF_ACTION_REQUIRED = 1 << 1,
-- 
2.50.1