From cec9ed6d7fa142732078b0b98dc83a45b393cadc Mon Sep 17 00:00:00 2001 From: Konstantin Belousov Date: Sun, 31 May 2009 14:52:45 +0000 Subject: [PATCH] Lock the real null vnode lock before substitution of vp->v_vnlock. This should not really matter for correctness, since vp->v_lock is not locked before the call, and null_lock() holds the interlock, but makes the control flow for reclaim more clear. Tested by: pho --- sys/fs/nullfs/null_vnops.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/sys/fs/nullfs/null_vnops.c b/sys/fs/nullfs/null_vnops.c index fd421e4341fa..e04b4d1b5fb0 100644 --- a/sys/fs/nullfs/null_vnops.c +++ b/sys/fs/nullfs/null_vnops.c @@ -683,14 +683,15 @@ null_reclaim(struct vop_reclaim_args *ap) * Use the interlock to protect the clearing of v_data to * prevent faults in null_lock(). */ + lockmgr(&vp->v_lock, LK_EXCLUSIVE, NULL); VI_LOCK(vp); vp->v_data = NULL; vp->v_object = NULL; vp->v_vnlock = &vp->v_lock; - if (lowervp) { - lockmgr(vp->v_vnlock, LK_EXCLUSIVE | LK_INTERLOCK, VI_MTX(vp)); + VI_UNLOCK(vp); + if (lowervp) vput(lowervp); - } else + else panic("null_reclaim: reclaiming a node with no lowervp"); free(xp, M_NULLFSNODE);