From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-it1-f199.google.com (mail-it1-f199.google.com [209.85.166.199]) by kanga.kvack.org (Postfix) with ESMTP id 76B146B1794 for ; Sun, 18 Nov 2018 19:48:18 -0500 (EST) Received: by mail-it1-f199.google.com with SMTP id e19-v6so6403178itc.0 for ; Sun, 18 Nov 2018 16:48:18 -0800 (PST) Received: from mail-sor-f65.google.com (mail-sor-f65.google.com. [209.85.220.65]) by mx.google.com with SMTPS id v195-v6sor43183485ita.7.2018.11.18.16.48.17 for (Google Transport Security); Sun, 18 Nov 2018 16:48:17 -0800 (PST) From: Yu Zhao Subject: [PATCH] mm: fix swap offset when replacing shmem page Date: Sun, 18 Nov 2018 17:47:19 -0700 Message-Id: <20181119004719.156411-1-yuzhao@google.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: owner-linux-mm@kvack.org List-ID: To: Hugh Dickins Cc: Andrew Morton , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Yu Zhao We used to have a single swap address space with swp_entry_t.val as its radix tree index. This is not the case anymore. Now Each swp_type() has its own address space and should use swp_offset() as radix tree index. Signed-off-by: Yu Zhao --- mm/shmem.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) diff --git a/mm/shmem.c b/mm/shmem.c index d44991ea5ed4..a92c6ae26915 100644 --- a/mm/shmem.c +++ b/mm/shmem.c @@ -1509,11 +1509,13 @@ static int shmem_replace_page(struct page **pagep, gfp_t gfp, { struct page *oldpage, *newpage; struct address_space *swap_mapping; - pgoff_t swap_index; + swp_entry_t entry; int error; + VM_BUG_ON(PageSwapCache(*pagep)); + oldpage = *pagep; - swap_index = page_private(oldpage); + entry.val = page_private(oldpage); swap_mapping = page_mapping(oldpage); /* @@ -1532,7 +1534,7 @@ static int shmem_replace_page(struct page **pagep, gfp_t gfp, __SetPageLocked(newpage); __SetPageSwapBacked(newpage); SetPageUptodate(newpage); - set_page_private(newpage, swap_index); + set_page_private(newpage, entry.val); SetPageSwapCache(newpage); /* @@ -1540,7 +1542,8 @@ static int shmem_replace_page(struct page **pagep, gfp_t gfp, * a nice clean interface for us to replace oldpage by newpage there. */ xa_lock_irq(&swap_mapping->i_pages); - error = shmem_replace_entry(swap_mapping, swap_index, oldpage, newpage); + error = shmem_replace_entry(swap_mapping, swp_offset(entry), + oldpage, newpage); if (!error) { __inc_node_page_state(newpage, NR_FILE_PAGES); __dec_node_page_state(oldpage, NR_FILE_PAGES); -- 2.19.1.1215.g8438c0b245-goog