[PATCH v3 18/18] mm/huge_memory: drop the redundant mapping argument of __split_frozen_folio

The mapping parameter only served as a non-NULL check to detect
whether page cache entries need updating.  The xa_state pointer
conveys exactly the same information: the anon split helper passes
NULL and the file split helper passes &xas, which is non-NULL iff
the folio is in the page cache.

Use the xas pointer instead and drop the parameter, along with its
kerneldoc entry.

Signed-off-by: Kairui Song <[email protected]>
---
 mm/huge_memory.c | 11 ++++-------
 1 file changed, 4 insertions(+), 7 deletions(-)

diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index 3e4c0fac7ba6..cc9f7e0d4194 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -3761,7 +3761,6 @@ static void __split_folio_to_order(struct folio *folio, int old_order,
  * @split_at: in buddy allocator like split, the folio containing @split_at
  *            will be split until its order becomes @new_order.
  * @xas: xa_state pointing to folio->mapping->i_pages and locked by caller
- * @mapping: @folio->mapping
  * @split_type: if the split is uniform or not (buddy allocator like split)
  *
  *
@@ -3794,7 +3793,7 @@ static void __split_folio_to_order(struct folio *folio, int old_order,
  */
 static int __split_frozen_folio(struct folio *folio, int new_order,
 		struct page *split_at, struct xa_state *xas,
-		struct address_space *mapping, enum split_type split_type)
+		enum split_type split_type)
 {
 	const bool is_anon = folio_test_anon(folio);
 	const bool is_swapcache = folio_test_swapcache(folio);
@@ -3816,7 +3815,7 @@ static int __split_frozen_folio(struct folio *folio, int new_order,
 		if ((is_anon || is_swapcache) && split_order == 1)
 			continue;
 
-		if (mapping) {
+		if (xas) {
 			/*
 			 * uniform split has xas_split_alloc() called before
 			 * irq is disabled to allocate enough memory, whereas
@@ -4030,8 +4029,7 @@ static int __folio_split_unmap_and_freeze(struct folio *folio, unsigned int new_
 	if (do_lru)
 		lruvec = folio_lruvec_lock(folio);
 
-	ret = __split_frozen_folio(folio, new_order, split_at, NULL,
-				   NULL, split_type);
+	ret = __split_frozen_folio(folio, new_order, split_at, NULL, split_type);
 
 	/*
 	 * Unfreeze the post-split folios and put them back to the right
@@ -4185,8 +4183,7 @@ static int __folio_split_unmap_and_freeze_file(struct folio *folio, unsigned int
 
 	/* lock lru list/PageCompound, ref frozen by page_ref_freeze */
 	lruvec = folio_lruvec_lock(folio);
-	ret = __split_frozen_folio(folio, new_order, split_at, &xas,
-				   mapping, split_type);
+	ret = __split_frozen_folio(folio, new_order, split_at, &xas, split_type);
 
 	/*
 	 * Unfreeze after-split folios and put them back to the right

-- 
2.55.0