From 240a59156d9bcfabceddb66be449e7b32fb5dc4a Mon Sep 17 00:00:00 2001 From: Chao Yu Date: Wed, 6 Mar 2019 17:30:59 +0800 Subject: f2fs: fix to add refcount once page is tagged PG_private As Gao Xiang reported in bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=202749 f2fs may skip pageout() due to incorrect page reference count. The problem here is that MM defined the rule [1] very clearly that once page was set with PG_private flag, we should increment the refcount in that page, also main flows like pageout(), migrate_page() will assume there is one additional page reference count if page_has_private() returns true. But currently, f2fs won't add/del refcount when changing PG_private flag. Anyway, f2fs should follow MM's rule to make MM's related flows running as expected. [1] https://lore.kernel.org/lkml/2b19b3c4-2bc4-15fa-15cc-27a13e5c7af1@aol.com/ Reported-by: Gao Xiang Signed-off-by: Chao Yu Signed-off-by: Jaegeuk Kim --- fs/f2fs/segment.c | 9 +++------ 1 file changed, 3 insertions(+), 6 deletions(-) (limited to 'fs/f2fs/segment.c') diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c index e730c334abba..aa7fe79b62b2 100644 --- a/fs/f2fs/segment.c +++ b/fs/f2fs/segment.c @@ -191,8 +191,7 @@ void f2fs_register_inmem_page(struct inode *inode, struct page *page) f2fs_trace_pid(page); - set_page_private(page, (unsigned long)ATOMIC_WRITTEN_PAGE); - SetPagePrivate(page); + f2fs_set_page_private(page, (unsigned long)ATOMIC_WRITTEN_PAGE); new = f2fs_kmem_cache_alloc(inmem_entry_slab, GFP_NOFS); @@ -280,8 +279,7 @@ next: ClearPageUptodate(page); clear_cold_data(page); } - set_page_private(page, 0); - ClearPagePrivate(page); + f2fs_clear_page_private(page); f2fs_put_page(page, 1); list_del(&cur->list); @@ -370,8 +368,7 @@ void f2fs_drop_inmem_page(struct inode *inode, struct page *page) kmem_cache_free(inmem_entry_slab, cur); ClearPageUptodate(page); - set_page_private(page, 0); - ClearPagePrivate(page); + f2fs_clear_page_private(page); f2fs_put_page(page, 0); trace_f2fs_commit_inmem_page(page, INMEM_INVALIDATE); -- cgit v1.2.3