From f1f724e4b523d444c5a598d74505aefa3d6844d2 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Mon, 1 Mar 2010 11:30:31 +0000 Subject: xfs: fix locking for inode cache radix tree tag updates The radix-tree code requires it's users to serialize tag updates against other updates to the tree. While XFS protects tag updates against each other it does not serialize them against updates of the tree contents, which can lead to tag corruption. Fix the inode cache to always take pag_ici_lock in exclusive mode when updating radix tree tags. Signed-off-by: Christoph Hellwig Reported-by: Patrick Schreurs Tested-by: Patrick Schreurs Signed-off-by: Alex Elder --- fs/xfs/xfs_iget.c | 19 +++++++++++++------ 1 file changed, 13 insertions(+), 6 deletions(-) (limited to 'fs/xfs/xfs_iget.c') diff --git a/fs/xfs/xfs_iget.c b/fs/xfs/xfs_iget.c index e281eb4a1c4..6845db90818 100644 --- a/fs/xfs/xfs_iget.c +++ b/fs/xfs/xfs_iget.c @@ -190,13 +190,12 @@ xfs_iget_cache_hit( trace_xfs_iget_reclaim(ip); /* - * We need to set XFS_INEW atomically with clearing the - * reclaimable tag so that we do have an indicator of the - * inode still being initialized. + * We need to set XFS_IRECLAIM to prevent xfs_reclaim_inode + * from stomping over us while we recycle the inode. We can't + * clear the radix tree reclaimable tag yet as it requires + * pag_ici_lock to be held exclusive. */ - ip->i_flags |= XFS_INEW; - ip->i_flags &= ~XFS_IRECLAIMABLE; - __xfs_inode_clear_reclaim_tag(mp, pag, ip); + ip->i_flags |= XFS_IRECLAIM; spin_unlock(&ip->i_flags_lock); read_unlock(&pag->pag_ici_lock); @@ -216,7 +215,15 @@ xfs_iget_cache_hit( trace_xfs_iget_reclaim(ip); goto out_error; } + + write_lock(&pag->pag_ici_lock); + spin_lock(&ip->i_flags_lock); + ip->i_flags &= ~(XFS_IRECLAIMABLE | XFS_IRECLAIM); + ip->i_flags |= XFS_INEW; + __xfs_inode_clear_reclaim_tag(mp, pag, ip); inode->i_state = I_NEW; + spin_unlock(&ip->i_flags_lock); + write_unlock(&pag->pag_ici_lock); } else { /* If the VFS inode is being torn down, pause and try again. */ if (!igrab(inode)) { -- cgit v1.2.3-70-g09d2