From 86693837593d7b4db461ccfbe58bd2211379c6c3 Mon Sep 17 00:00:00 2001
From: Muchun Song <songmuchun@bytedance.com>
Date: Fri, 12 Jun 2026 11:59:02 +0800
Subject: [PATCH] mm/hugetlb: remove unused bootmem cma field

struct huge_bootmem_page no longer needs to keep the CMA pointer.  The
bootmem path only needs to remember whether a huge page came from CMA,
which is already encoded in the flags field.

Set HUGE_BOOTMEM_CMA when the page is allocated, drop the unused cma field
together with the redundant assignments, and simplify the early CMA
bootmem allocation fallback path now that the cma pointer no longer has to
be stored in struct huge_bootmem_page.

Link: https://lore.kernel.org/20260612035903.2468601-19-songmuchun@bytedance.com
Signed-off-by: Muchun Song <songmuchun@bytedance.com>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com>
Cc: David Hildenbrand <david@kernel.org>
Cc: Frank van der Linden <fvdl@google.com>
Cc: Liam R. Howlett <liam@infradead.org>
Cc: Lorenzo Stoakes <ljs@kernel.org>
Cc: Madhavan Srinivasan <maddy@linux.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Mike Rapoport (Microsoft) <rppt@kernel.org>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Oscar Salvador (SUSE) <osalvador@kernel.org>
Cc: "Ritesh Harjani (IBM)" <ritesh.list@gmail.com>
Cc: Usama Arif <usama.arif@linux.dev>
Cc: Vlastimil Babka <vbabka@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---
 mm/hugetlb.c     |  5 +----
 mm/hugetlb_cma.c | 29 +++++++++++------------------
 mm/internal.h    |  2 --
 3 files changed, 12 insertions(+), 24 deletions(-)

diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 1bd9d12edb3e..5bfbfc7e463e 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -3076,10 +3076,7 @@ static bool __init alloc_bootmem_huge_page(struct hstate *h, int nid)
 	 */
 	INIT_LIST_HEAD(&m->list);
 	m->hstate = h;
-	if (!hugetlb_early_cma(h)) {
-		m->cma = NULL;
-		m->flags = 0;
-	}
+	m->flags = hugetlb_early_cma(h) ? HUGE_BOOTMEM_CMA : 0;
 
 	/* CMA pages: zone-crossing is validated in hugetlb_cma_reserve(). */
 	if (!hugetlb_early_cma(h) &&
diff --git a/mm/hugetlb_cma.c b/mm/hugetlb_cma.c
index e487d0ffffc0..4dfce68b354a 100644
--- a/mm/hugetlb_cma.c
+++ b/mm/hugetlb_cma.c
@@ -59,31 +59,24 @@ struct folio *hugetlb_cma_alloc_frozen_folio(int order, gfp_t gfp_mask,
 void * __init hugetlb_cma_alloc_bootmem(struct hstate *h, int nid, bool node_exact)
 {
 	struct cma *cma;
-	struct huge_bootmem_page *m;
+	void *m;
 	int node;
 
 	cma = hugetlb_cma[nid];
 	m = cma_reserve_early(cma, huge_page_size(h));
-	if (!m) {
-		if (node_exact)
-			return NULL;
+	if (m || node_exact)
+		return m;
 
-		for_each_node_mask(node, hugetlb_bootmem_nodes) {
-			cma = hugetlb_cma[node];
-			if (!cma || node == nid)
-				continue;
-			m = cma_reserve_early(cma, huge_page_size(h));
-			if (m)
-				break;
-		}
+	for_each_node_mask(node, hugetlb_bootmem_nodes) {
+		cma = hugetlb_cma[node];
+		if (!cma || node == nid)
+			continue;
+		m = cma_reserve_early(cma, huge_page_size(h));
+		if (m)
+			return m;
 	}
 
-	if (m) {
-		m->flags = HUGE_BOOTMEM_CMA;
-		m->cma = cma;
-	}
-
-	return m;
+	return NULL;
 }
 
 static int __init cmdline_parse_hugetlb_cma(char *p)
diff --git a/mm/internal.h b/mm/internal.h
index 3401759924d9..39c9564fba0e 100644
--- a/mm/internal.h
+++ b/mm/internal.h
@@ -24,13 +24,11 @@
 
 struct folio_batch;
 struct hstate;
-struct cma;
 
 struct huge_bootmem_page {
 	struct list_head list;
 	struct hstate *hstate;
 	unsigned long flags;
-	struct cma *cma;
 };
 
 /*