[PATCH v1 06/10] mm/huge_memory: remove folio split check for READ_ONLY_THP_FOR_FS

Zi Yan
2026-03-27T01:43:18Z

Without READ_ONLY_THP_FOR_FS, large file-backed folios cannot be created by
a FS without large folio support. The check is no longer needed.

Signed-off-by: Zi Yan <ziy@nvidia.com>
---
mm/huge_memory.c | 22 ----------------------
1 file changed, 22 deletions(-)

diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index 1da1467328a3..30eddcbf86f1 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -3732,28 +3732,6 @@ int folio_check_splittable(struct folio *folio, unsigned int new_order,
/* order-1 is not supported for anonymous THP. */
if (new_order == 1)
return -EINVAL;
- } else if (split_type == SPLIT_TYPE_NON_UNIFORM || new_order) {
- if (IS_ENABLED(CONFIG_READ_ONLY_THP_FOR_FS) &&
- !mapping_large_folio_support(folio->mapping)) {
- /*
- * We can always split a folio down to a single page
- * (new_order == 0) uniformly.
- *
- * For any other scenario
- * a) uniform split targeting a large folio
- * (new_order > 0)
- * b) any non-uniform split
- * we must confirm that the file system supports large
- * folios.
- *
- * Note that we might still have THPs in such
- * mappings, which is created from khugepaged when
- * CONFIG_READ_ONLY_THP_FOR_FS is enabled. But in that
- * case, the mapping does not actually support large
- * folios properly.
- */
- return -EINVAL;
- }
}

/*
--
2.43.0