From b54c2ca475fa7d7450a45b6d778dae9dbe0bcbfe Mon Sep 17 00:00:00 2001 From: Tristan Ye Date: Fri, 19 Mar 2010 09:21:10 +0800 Subject: Ocfs2: Handle deletion of reflinked oprhan inodes correctly. The rule is that all inodes in the orphan dir have ORPHANED_FL, otherwise we treated it as an ERROR. This rule works well except for some rare cases of reflink operation: http://oss.oracle.com/bugzilla/show_bug.cgi?id=1215 The problem is caused by how reflink and our orphan_scan thread interact. * The orphan scan pulls the orphans into a queue first, then runs the queue at a later time. We only hold the orphan_dir's lock during scanning. * Reflink create a oprhaned target in orphan_dir as its first step. It removes the target and clears the flag as the final step. These two steps take the orphan_dir's lock, but it is not held for the duration. Based on the above semantics, a reflink inode can be moved out of the orphan dir and have its ORPHANED_FL cleared before the queue of orphans is run. This leads to a ERROR in ocfs2_query_wipde_inode(). This patch teaches ocfs2_query_wipe_inode() to detect previously orphaned reflink targets. If a reflink fails or a crash occurs during the relfink operation, the inode will retain ORPHANED_FL and will be properly wiped. Signed-off-by: Tristan Ye Signed-off-by: Joel Becker --- fs/ocfs2/inode.c | 15 +++++++++++++++ 1 file changed, 15 insertions(+) (limited to 'fs') diff --git a/fs/ocfs2/inode.c b/fs/ocfs2/inode.c index 278a223aae14..ab207901d32a 100644 --- a/fs/ocfs2/inode.c +++ b/fs/ocfs2/inode.c @@ -891,6 +891,21 @@ static int ocfs2_query_inode_wipe(struct inode *inode, /* Do some basic inode verification... */ di = (struct ocfs2_dinode *) di_bh->b_data; if (!(di->i_flags & cpu_to_le32(OCFS2_ORPHANED_FL))) { + /* + * Inodes in the orphan dir must have ORPHANED_FL. The only + * inodes that come back out of the orphan dir are reflink + * targets. A reflink target may be moved out of the orphan + * dir between the time we scan the directory and the time we + * process it. This would lead to HAS_REFCOUNT_FL being set but + * ORPHANED_FL not. + */ + if (di->i_dyn_features & cpu_to_le16(OCFS2_HAS_REFCOUNT_FL)) { + mlog(0, "Reflinked inode %llu is no longer orphaned. " + "it shouldn't be deleted\n", + (unsigned long long)oi->ip_blkno); + goto bail; + } + /* for lack of a better error? */ status = -EEXIST; mlog(ML_ERROR, -- cgit v1.2.3-59-g8ed1b