From 6acd8866885de07066b56c439cb61edacb8ddb8e Mon Sep 17 00:00:00 2001 From: Zi Yan Date: Wed, 22 Jan 2025 11:19:27 -0500 Subject: [PATCH] mm/huge_memory: allow split shmem large folio to any lower order Commit 4d684b5f92ba ("mm: shmem: add large folio support for tmpfs") has added large folio support to shmem. Remove the restriction in split_huge_page*(). Link: https://lkml.kernel.org/r/20250122161928.1240637-2-ziy@nvidia.com Signed-off-by: Zi Yan Reviewed-by: Baolin Wang Reviewed-by: Yang Shi Cc: David Hildenbrand Cc: Hugh Dickins Cc: John Hubbard Cc: Kefeng Wang Cc: Kirill A. Shuemov Cc: Miaohe Lin Cc: Matthew Wilcox Cc: Ryan Roberts Cc: Yu Zhao Signed-off-by: Andrew Morton --- mm/huge_memory.c | 8 +------- 1 file changed, 1 insertion(+), 7 deletions(-) diff --git a/mm/huge_memory.c b/mm/huge_memory.c index c40b42a1015a..364c471ae10e 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -3299,7 +3299,7 @@ static void __split_huge_page(struct page *page, struct list_head *list, /* Some pages can be beyond EOF: drop them from page cache */ if (tail->index >= end) { if (shmem_mapping(folio->mapping)) - nr_dropped++; + nr_dropped += new_nr; else if (folio_test_clear_dirty(tail)) folio_account_cleaned(tail, inode_to_wb(folio->mapping->host)); @@ -3465,12 +3465,6 @@ int split_huge_page_to_list_to_order(struct page *page, struct list_head *list, return -EINVAL; } } else if (new_order) { - /* Split shmem folio to non-zero order not supported */ - if (shmem_mapping(folio->mapping)) { - VM_WARN_ONCE(1, - "Cannot split shmem folio to non-0 order"); - return -EINVAL; - } /* * No split if the file system does not support large folio. * Note that we might still have THPs in such mappings due to -- 2.50.1