From 9f5ab03f7fc57c70d410b5a774f18a90972184d1 Mon Sep 17 00:00:00 2001 From: Hao Li Date: Tue, 8 Dec 2020 10:08:43 +0800 Subject: [PATCH] fs: Handle I_DONTCACHE in iput_final() instead of generic_drop_inode() [ Upstream commit 88149082bb8ef31b289673669e080ec6a00c2e59 ] If generic_drop_inode() returns true, it means iput_final() can evict this inode regardless of whether it is dirty or not. If we check I_DONTCACHE in generic_drop_inode(), any inode with this bit set will be evicted unconditionally. This is not the desired behavior because I_DONTCACHE only means the inode shouldn't be cached on the LRU list. As for whether we need to evict this inode, this is what generic_drop_inode() should do. This patch corrects the usage of I_DONTCACHE. This patch was proposed in [1]. [1]: https://lore.kernel.org/linux-fsdevel/20200831003407.GE12096@dread.disaster.area/ Fixes: dae2f8ed7992 ("fs: Lift XFS_IDONTCACHE to the VFS layer") Signed-off-by: Hao Li Reviewed-by: Dave Chinner Reviewed-by: Ira Weiny Signed-off-by: Al Viro Signed-off-by: Sasha Levin --- fs/inode.c | 4 +++- include/linux/fs.h | 3 +-- 2 files changed, 4 insertions(+), 3 deletions(-) diff --git a/fs/inode.c b/fs/inode.c index 9d78c37..5eea991 100644 --- a/fs/inode.c +++ b/fs/inode.c @@ -1627,7 +1627,9 @@ static void iput_final(struct inode *inode) else drop = generic_drop_inode(inode); - if (!drop && (sb->s_flags & SB_ACTIVE)) { + if (!drop && + !(inode->i_state & I_DONTCACHE) && + (sb->s_flags & SB_ACTIVE)) { inode_add_lru(inode); spin_unlock(&inode->i_lock); return; diff --git a/include/linux/fs.h b/include/linux/fs.h index 8667d0c..8bde32c 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -2878,8 +2878,7 @@ extern int inode_needs_sync(struct inode *inode); extern int generic_delete_inode(struct inode *inode); static inline int generic_drop_inode(struct inode *inode) { - return !inode->i_nlink || inode_unhashed(inode) || - (inode->i_state & I_DONTCACHE); + return !inode->i_nlink || inode_unhashed(inode); } extern void d_mark_dontcache(struct inode *inode); -- 2.7.4