6.18-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Usama Arif <usamaarif642@gmail.com>

[ Upstream commit a743e0af503a633e4ca68a100d9b2a1a071fe8ae ]

This is a common condition used to skip operations that cannot be
performed on gigantic pages when runtime support is disabled.  This helper
is introduced as the condition will exist even more when allowing
"overcommit" of gigantic hugepages.  No functional change intended with
this patch.

Link: https://lkml.kernel.org/r/20251009172433.4158118-1-usamaarif642@gmail.com
Signed-off-by: Usama Arif <usamaarif642@gmail.com>
Suggested-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Shakeel Butt <shakeel.butt@linux.dev>
Reviewed-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Acked-by: David Hildenbrand <david@redhat.com>
Acked-by: Oscar Salvador <osalvador@suse.de>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Rik van Riel <riel@surriel.com>
Cc: SeongJae Park <sj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Stable-dep-of: a363c62a653c ("mm/hugetlb: do not dissolve gigantic pages without runtime support")
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 mm/hugetlb.c |   21 ++++++++++++++++-----
 1 file changed, 16 insertions(+), 5 deletions(-)

--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -138,6 +138,17 @@ static void hugetlb_free_folio(struct fo
 	folio_put(folio);
 }
 
+/*
+ * Check if the hstate represents gigantic pages but gigantic page
+ * runtime support is not available. This is a common condition used to
+ * skip operations that cannot be performed on gigantic pages when runtime
+ * support is disabled.
+ */
+static inline bool hstate_is_gigantic_no_runtime(struct hstate *h)
+{
+	return hstate_is_gigantic(h) && !gigantic_page_runtime_supported();
+}
+
 static inline bool subpool_is_free(struct hugepage_subpool *spool)
 {
 	if (spool->count)
@@ -1538,7 +1549,7 @@ static void remove_hugetlb_folio(struct
 	VM_BUG_ON_FOLIO(hugetlb_cgroup_from_folio_rsvd(folio), folio);
 
 	lockdep_assert_held(&hugetlb_lock);
-	if (hstate_is_gigantic(h) && !gigantic_page_runtime_supported())
+	if (hstate_is_gigantic_no_runtime(h))
 		return;
 
 	list_del(&folio->lru);
@@ -1600,7 +1611,7 @@ static void __update_and_free_hugetlb_fo
 {
 	bool clear_flag = folio_test_hugetlb_vmemmap_optimized(folio);
 
-	if (hstate_is_gigantic(h) && !gigantic_page_runtime_supported())
+	if (hstate_is_gigantic_no_runtime(h))
 		return;
 
 	/*
@@ -2496,7 +2507,7 @@ static void return_unused_surplus_pages(
 	/* Uncommit the reservation */
 	h->resv_huge_pages -= unused_resv_pages;
 
-	if (hstate_is_gigantic(h) && !gigantic_page_runtime_supported())
+	if (hstate_is_gigantic_no_runtime(h))
 		goto out;
 
 	/*
@@ -3711,7 +3722,7 @@ static void __init hugetlb_init_hstates(
 		 * - If CMA allocation is possible, we can not demote
 		 *   HUGETLB_PAGE_ORDER or smaller size pages.
 		 */
-		if (hstate_is_gigantic(h) && !gigantic_page_runtime_supported())
+		if (hstate_is_gigantic_no_runtime(h))
 			continue;
 		if (hugetlb_cma_total_size() && h->order <= HUGETLB_PAGE_ORDER)
 			continue;
@@ -4188,7 +4199,7 @@ static ssize_t __nr_hugepages_store_comm
 	int err;
 	nodemask_t nodes_allowed, *n_mask;
 
-	if (hstate_is_gigantic(h) && !gigantic_page_runtime_supported())
+	if (hstate_is_gigantic_no_runtime(h))
 		return -EINVAL;
 
 	if (nid == NUMA_NO_NODE) {