arch, mm: make releasing of memory to page allocator more explicit

The point where the memory is released from memblock to the buddy
allocator is hidden inside arch-specific mem_init()s and the call to
memblock_free_all() is needlessly duplicated in every artiste cure and
after introduction of arch_mm_preinit() hook, mem_init() implementation on
many architecture only contains the call to memblock_free_all().

Pull memblock_free_all() call into mm_core_init() and drop mem_init() on
relevant architectures to make it more explicit where the free memory is
released from memblock to the buddy allocator and to reduce code
duplication in architecture specific code.

Link: https://lkml.kernel.org/r/20250313135003.836600-14-rppt@kernel.org
Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Acked-by: Dave Hansen <dave.hansen@linux.intel.com>	[x86]
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>	[m68k]
Tested-by: Mark Brown <broonie@kernel.org>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Andreas Larsson <andreas@gaisler.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Borislav Betkov <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Dinh Nguyen <dinguyen@kernel.org>
Cc: Gerald Schaefer <gerald.schaefer@linux.ibm.com>
Cc: Guo Ren (csky) <guoren@kernel.org>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiaxun Yang <jiaxun.yang@flygoat.com>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Cc: Madhavan Srinivasan <maddy@linux.ibm.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Russel King <linux@armlinux.org.uk>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleinxer <tglx@linutronix.de>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Vineet Gupta <vgupta@kernel.org>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

27 files changed, 7 insertions, 136 deletions

diff --git a/arch/alpha/mm/init.c b/arch/alpha/mm/init.c
index 3ab2d2f3c917..2d491b8cdab9 100644
--- a/arch/alpha/mm/init.c
+++ b/arch/alpha/mm/init.c
@@ -273,12 +273,6 @@ srm_paging_stop (void)
 }
 #endif
 
-void __init
-mem_init(void)
-{
-	memblock_free_all();
-}
-
 static const pgprot_t protection_map[16] = {
 	[VM_NONE]					= _PAGE_P(_PAGE_FOE | _PAGE_FOW |
 								  _PAGE_FOR),
diff --git a/arch/arc/mm/init.c b/arch/arc/mm/init.c
index 90715b4a0bfa..a73cc94f806e 100644
--- a/arch/arc/mm/init.c
+++ b/arch/arc/mm/init.c
@@ -169,17 +169,6 @@ void __init arch_mm_preinit(void)
 	BUILD_BUG_ON((PTRS_PER_PTE * sizeof(pte_t)) > PAGE_SIZE);
 }
 
-/*
- * mem_init - initializes memory
- *
- * Frees up bootmem
- * Calculates and displays memory available/used
- */
-void __init mem_init(void)
-{
-	memblock_free_all();
-}
-
 #ifdef CONFIG_HIGHMEM
 int pfn_valid(unsigned long pfn)
 {
diff --git a/arch/arm/mm/init.c b/arch/arm/mm/init.c
index 7222100b0631..54bdca025c9f 100644
--- a/arch/arm/mm/init.c
+++ b/arch/arm/mm/init.c
@@ -263,17 +263,6 @@ void __init arch_mm_preinit(void)
 #endif
 }
 
-/*
- * mem_init() marks the free areas in the mem_map and tells us how much
- * memory is free.  This is done after various parts of the system have
- * claimed their memory after the kernel image.
- */
-void __init mem_init(void)
-{
-	/* this will put all unused low memory onto the freelists */
-	memblock_free_all();
-}
-
 #ifdef CONFIG_STRICT_KERNEL_RWX
 struct section_perm {
 	const char *name;
diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c
index 2312e3812043..4b966d5709d2 100644
--- a/arch/arm64/mm/init.c
+++ b/arch/arm64/mm/init.c
@@ -406,17 +406,6 @@ void __init arch_mm_preinit(void)
 	}
 }
 
-/*
- * mem_init() marks the free areas in the mem_map and tells us how much memory
- * is free.  This is done after various parts of the system have claimed their
- * memory after the kernel image.
- */
-void __init mem_init(void)
-{
-	/* this will put all unused low memory onto the freelists */
-	memblock_free_all();
-}
-
 void free_initmem(void)
 {
 	void *lm_init_begin = lm_alias(__init_begin);
diff --git a/arch/csky/mm/init.c b/arch/csky/mm/init.c
index 3914c2b873da..573da66b2543 100644
--- a/arch/csky/mm/init.c
+++ b/arch/csky/mm/init.c
@@ -42,11 +42,6 @@ unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)]
 						__page_aligned_bss;
 EXPORT_SYMBOL(empty_zero_page);
 
-void __init mem_init(void)
-{
-	memblock_free_all();
-}
-
 void free_initmem(void)
 {
 	free_initmem_default(-1);
diff --git a/arch/hexagon/mm/init.c b/arch/hexagon/mm/init.c
index d412c2314509..34eb9d424b96 100644
--- a/arch/hexagon/mm/init.c
+++ b/arch/hexagon/mm/init.c
@@ -43,24 +43,6 @@ DEFINE_SPINLOCK(kmap_gen_lock);
 /*  checkpatch says don't init this to 0.  */
 unsigned long long kmap_generation;
 
-/*
- * mem_init - initializes memory
- *
- * Frees up bootmem
- * Fixes up more stuff for HIGHMEM
- * Calculates and displays memory available/used
- */
-void __init mem_init(void)
-{
-	/*  No idea where this is actually declared.  Seems to evade LXR.  */
-	memblock_free_all();
-
-	/*
-	 *  To-Do:  someone somewhere should wipe out the bootmem map
-	 *  after we're done?
-	 */
-}
-
 void sync_icache_dcache(pte_t pte)
 {
 	unsigned long addr;
diff --git a/arch/loongarch/kernel/numa.c b/arch/loongarch/kernel/numa.c
index 8eb489725b1a..30a72fd528c0 100644
--- a/arch/loongarch/kernel/numa.c
+++ b/arch/loongarch/kernel/numa.c
@@ -387,11 +387,6 @@ void __init paging_init(void)
 	free_area_init(zones_size);
 }
 
-void __init mem_init(void)
-{
-	memblock_free_all();
-}
-
 int pcibus_to_node(struct pci_bus *bus)
 {
 	return dev_to_node(&bus->dev);
diff --git a/arch/loongarch/mm/init.c b/arch/loongarch/mm/init.c
index 6affa3609188..fdb7f73ad160 100644
--- a/arch/loongarch/mm/init.c
+++ b/arch/loongarch/mm/init.c
@@ -75,11 +75,6 @@ void __init paging_init(void)
 
 	free_area_init(max_zone_pfns);
 }
-
-void __init mem_init(void)
-{
-	memblock_free_all();
-}
 #endif /* !CONFIG_NUMA */
 
 void __ref free_initmem(void)
diff --git a/arch/m68k/mm/init.c b/arch/m68k/mm/init.c
index 8b11d0d545aa..488411af1b3f 100644
--- a/arch/m68k/mm/init.c
+++ b/arch/m68k/mm/init.c
@@ -121,7 +121,5 @@ static inline void init_pointer_tables(void)
 
 void __init mem_init(void)
 {
-	/* this will put all memory onto the freelists */
-	memblock_free_all();
 	init_pointer_tables();
 }
diff --git a/arch/microblaze/mm/init.c b/arch/microblaze/mm/init.c
index 3e664e0efc33..65f0d1fb8a2a 100644
--- a/arch/microblaze/mm/init.c
+++ b/arch/microblaze/mm/init.c
@@ -107,9 +107,6 @@ void __init setup_memory(void)
 
 void __init mem_init(void)
 {
-	/* this will put all memory onto the freelists */
-	memblock_free_all();
-
 	mem_init_done = 1;
 }
 
diff --git a/arch/mips/mm/init.c b/arch/mips/mm/init.c
index eec38e7735dd..a673d3d68254 100644
--- a/arch/mips/mm/init.c
+++ b/arch/mips/mm/init.c
@@ -451,11 +451,6 @@ void __init arch_mm_preinit(void)
 }
 #endif /* !CONFIG_NUMA */
 
-void __init mem_init(void)
-{
-	memblock_free_all();
-}
-
 void free_init_pages(const char *what, unsigned long begin, unsigned long end)
 {
 	unsigned long pfn;
diff --git a/arch/nios2/mm/init.c b/arch/nios2/mm/init.c
index 4ba8dfa0d238..94efa3de3933 100644
--- a/arch/nios2/mm/init.c
+++ b/arch/nios2/mm/init.c
@@ -60,12 +60,6 @@ void __init paging_init(void)
 			(unsigned long)empty_zero_page + PAGE_SIZE);
 }
 
-void __init mem_init(void)
-{
-	/* this will put all memory onto the freelists */
-	memblock_free_all();
-}
-
 void __init mmu_init(void)
 {
 	flush_tlb_all();
diff --git a/arch/openrisc/mm/init.c b/arch/openrisc/mm/init.c
index 72c5952607ac..be1c2eb8bb94 100644
--- a/arch/openrisc/mm/init.c
+++ b/arch/openrisc/mm/init.c
@@ -196,9 +196,6 @@ void __init mem_init(void)
 	/* clear the zero-page */
 	memset((void *)empty_zero_page, 0, PAGE_SIZE);
 
-	/* this will put all low memory onto the freelists */
-	memblock_free_all();
-
 	printk("mem_init_done ...........................................\n");
 	mem_init_done = 1;
 	return;
diff --git a/arch/parisc/mm/init.c b/arch/parisc/mm/init.c
index 4fbe354dc9b4..14270715d754 100644
--- a/arch/parisc/mm/init.c
+++ b/arch/parisc/mm/init.c
@@ -562,8 +562,6 @@ void __init mem_init(void)
 	BUILD_BUG_ON(TMPALIAS_MAP_START >= 0x80000000);
 #endif
 
-	memblock_free_all();
-
 #ifdef CONFIG_PA11
 	if (boot_cpu_data.cpu_type == pcxl2 || boot_cpu_data.cpu_type == pcxl) {
 		pcxl_dma_start = (unsigned long)SET_MAP_OFFSET(MAP_START);
diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c
index 68efdaf14e58..d8fe11b64259 100644
--- a/arch/powerpc/mm/mem.c
+++ b/arch/powerpc/mm/mem.c
@@ -327,11 +327,6 @@ void __init arch_mm_preinit(void)
 #endif /* CONFIG_PPC32 */
 }
 
-void __init mem_init(void)
-{
-	memblock_free_all();
-}
-
 void free_initmem(void)
 {
 	ppc_md.progress = ppc_printk_progress;
diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c
index 9efadabf6be1..79b649f6de72 100644
--- a/arch/riscv/mm/init.c
+++ b/arch/riscv/mm/init.c
@@ -196,11 +196,6 @@ void __init arch_mm_preinit(void)
 	print_vm_layout();
 }
 
-void __init mem_init(void)
-{
-	memblock_free_all();
-}
-
 /* Limit the memory size via mem. */
 static phys_addr_t memory_limit;
 #ifdef CONFIG_XIP_KERNEL
diff --git a/arch/s390/mm/init.c b/arch/s390/mm/init.c
index e771b7458d8b..5b7b7b281334 100644
--- a/arch/s390/mm/init.c
+++ b/arch/s390/mm/init.c
@@ -165,12 +165,6 @@ void __init arch_mm_preinit(void)
 	setup_zero_pages();	/* Setup zeroed pages. */
 }
 
-void __init mem_init(void)
-{
-	/* this will put all low memory onto the freelists */
-	memblock_free_all();
-}
-
 unsigned long memory_block_size_bytes(void)
 {
 	/*
diff --git a/arch/sh/mm/init.c b/arch/sh/mm/init.c
index 6d459ffba4bc..99e302eeeec1 100644
--- a/arch/sh/mm/init.c
+++ b/arch/sh/mm/init.c
@@ -330,8 +330,6 @@ unsigned int mem_init_done = 0;
 
 void __init mem_init(void)
 {
-	memblock_free_all();
-
 	/* Set this up early, so we can take care of the zero page */
 	cpu_cache_init();
 
diff --git a/arch/sparc/mm/init_32.c b/arch/sparc/mm/init_32.c
index e16c32c5728f..fdc93dd12c3e 100644
--- a/arch/sparc/mm/init_32.c
+++ b/arch/sparc/mm/init_32.c
@@ -264,11 +264,6 @@ void __init arch_mm_preinit(void)
 	taint_real_pages();
 }
 
-void __init mem_init(void)
-{
-	memblock_free_all();
-}
-
 void sparc_flush_page_to_ram(struct page *page)
 {
 	unsigned long vaddr = (unsigned long)page_address(page);
diff --git a/arch/sparc/mm/init_64.c b/arch/sparc/mm/init_64.c
index 34d46adb9571..760818950464 100644
--- a/arch/sparc/mm/init_64.c
+++ b/arch/sparc/mm/init_64.c
@@ -2505,8 +2505,6 @@ static void __init register_page_bootmem_info(void)
 }
 void __init mem_init(void)
 {
-	memblock_free_all();
-
 	/*
 	 * Must be done after boot memory is put on freelist, because here we
 	 * might set fields in deferred struct pages that have not yet been
diff --git a/arch/um/kernel/mem.c b/arch/um/kernel/mem.c
index cce387438e60..379f33a1babf 100644
--- a/arch/um/kernel/mem.c
+++ b/arch/um/kernel/mem.c
@@ -71,8 +71,6 @@ void __init arch_mm_preinit(void)
 
 void __init mem_init(void)
 {
-	/* this will put all low memory onto the freelists */
-	memblock_free_all();
 	kmalloc_ok = 1;
 }
 
diff --git a/arch/x86/mm/init_32.c b/arch/x86/mm/init_32.c
index 16664c5464b5..95b2758b4e4d 100644
--- a/arch/x86/mm/init_32.c
+++ b/arch/x86/mm/init_32.c
@@ -702,9 +702,6 @@ void __init arch_mm_preinit(void)
 
 void __init mem_init(void)
 {
-	/* this will put all low memory onto the freelists */
-	memblock_free_all();
-
 	after_bootmem = 1;
 	x86_init.hyper.init_after_bootmem();
 
diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c
index a88f7db8089e..d67f15386ea2 100644
--- a/arch/x86/mm/init_64.c
+++ b/arch/x86/mm/init_64.c
@@ -1357,8 +1357,6 @@ void __init mem_init(void)
 {
 	/* clear_bss() already clear the empty_zero_page */
 
-	/* this will put all memory onto the freelists */
-	memblock_free_all();
 	after_bootmem = 1;
 	x86_init.hyper.init_after_bootmem();
 
diff --git a/arch/xtensa/mm/init.c b/arch/xtensa/mm/init.c
index 47ecbe28263e..cc52733a0649 100644
--- a/arch/xtensa/mm/init.c
+++ b/arch/xtensa/mm/init.c
@@ -129,15 +129,6 @@ void __init zones_init(void)
 	print_vm_layout();
 }
 
-/*
- * Initialize memory pages.
- */
-
-void __init mem_init(void)
-{
-	memblock_free_all();
-}
-
 static void __init parse_memmap_one(char *p)
 {
 	char *oldp;
diff --git a/include/linux/memblock.h b/include/linux/memblock.h
index e79eb6ac516f..ef5a1ecc6e59 100644
--- a/include/linux/memblock.h
+++ b/include/linux/memblock.h
@@ -133,7 +133,6 @@ int memblock_mark_nomap(phys_addr_t base, phys_addr_t size);
 int memblock_clear_nomap(phys_addr_t base, phys_addr_t size);
 int memblock_reserved_mark_noinit(phys_addr_t base, phys_addr_t size);
 
-void memblock_free_all(void);
 void memblock_free(void *ptr, size_t size);
 void reset_all_zones_managed_pages(void);
 
diff --git a/mm/internal.h b/mm/internal.h
index 558c8e2a3d94..2f52a65272c1 100644
--- a/mm/internal.h
+++ b/mm/internal.h
@@ -1475,7 +1475,8 @@ static inline bool gup_must_unshare(struct vm_area_struct *vma,
 }
 
 extern bool mirrored_kernelcore;
-extern bool memblock_has_mirror(void);
+bool memblock_has_mirror(void);
+void memblock_free_all(void);
 
 static __always_inline void vma_set_range(struct vm_area_struct *vma,
 					  unsigned long start, unsigned long end,
diff --git a/mm/mm_init.c b/mm/mm_init.c
index 6844de516a50..c82b0162f1cb 100644
--- a/mm/mm_init.c
+++ b/mm/mm_init.c
@@ -2738,6 +2738,10 @@ void __init __weak arch_mm_preinit(void)
 {
 }
 
+void __init __weak mem_init(void)
+{
+}
+
 /*
  * Set up kernel memory allocators
  */
@@ -2761,6 +2765,7 @@ void __init mm_core_init(void)
 	report_meminit();
 	kmsan_init_shadow();
 	stack_depot_early_init();
+	memblock_free_all();
 	mem_init();
 	kmem_cache_init();
 	/*