Module Name: src
Committed By: hannken
Date: Sun Feb 9 17:15:51 UTC 2014
Modified Files:
src/sys/miscfs/genfs: layer_subr.c
Log Message:
When layer_node_alloc() finds another thread already inserted the node
into the hashlist and discards the now unneeded node it will raise a
panic "dead but not clean".
Reorder the initialization and use ungetnewvnode() to discard the node.
To generate a diff of this commit:
cvs rdiff -u -r1.33 -r1.34 src/sys/miscfs/genfs/layer_subr.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/miscfs/genfs/layer_subr.c
diff -u src/sys/miscfs/genfs/layer_subr.c:1.33 src/sys/miscfs/genfs/layer_subr.c:1.34
--- src/sys/miscfs/genfs/layer_subr.c:1.33 Wed Jan 29 08:27:04 2014
+++ src/sys/miscfs/genfs/layer_subr.c Sun Feb 9 17:15:51 2014
@@ -1,4 +1,4 @@
-/* $NetBSD: layer_subr.c,v 1.33 2014/01/29 08:27:04 hannken Exp $ */
+/* $NetBSD: layer_subr.c,v 1.34 2014/02/09 17:15:51 hannken Exp $ */
/*
* Copyright (c) 1999 National Aeronautics & Space Administration
@@ -69,7 +69,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: layer_subr.c,v 1.33 2014/01/29 08:27:04 hannken Exp $");
+__KERNEL_RCSID(0, "$NetBSD: layer_subr.c,v 1.34 2014/02/09 17:15:51 hannken Exp $");
#include <sys/param.h>
#include <sys/systm.h>
@@ -187,7 +187,6 @@ layer_node_alloc(struct mount *mp, struc
struct layer_node *xp;
struct vnode *vp, *nvp;
int error;
- extern int (**dead_vnodeop_p)(void *);
/* Get a new vnode and share its interlock with underlying vnode. */
error = getnewvnode(lmp->layerm_tag, mp, lmp->layerm_vnodeop_p,
@@ -209,31 +208,25 @@ layer_node_alloc(struct mount *mp, struc
spec_node_init(vp, lowervp->v_rdev);
}
- vp->v_data = xp;
- vp->v_vflag = (vp->v_vflag & ~VV_MPSAFE) |
- (lowervp->v_vflag & VV_MPSAFE);
- xp->layer_vnode = vp;
- xp->layer_lowervp = lowervp;
- xp->layer_flags = 0;
-
/*
* Before inserting the node into the hash, check if other thread
* did not race with us. If so - return that node, destroy ours.
*/
mutex_enter(&lmp->layerm_hashlock);
if ((nvp = layer_node_find(mp, lowervp)) != NULL) {
- /* Free the structures we have created. */
- if (vp->v_type == VBLK || vp->v_type == VCHR)
- spec_node_destroy(vp);
-
- vp->v_type = VBAD; /* node is discarded */
- vp->v_op = dead_vnodeop_p; /* so ops will still work */
- vrele(vp); /* get rid of it. */
+ ungetnewvnode(vp);
kmem_free(xp, lmp->layerm_size);
*vpp = nvp;
return 0;
}
+ vp->v_data = xp;
+ vp->v_vflag = (vp->v_vflag & ~VV_MPSAFE) |
+ (lowervp->v_vflag & VV_MPSAFE);
+ xp->layer_vnode = vp;
+ xp->layer_lowervp = lowervp;
+ xp->layer_flags = 0;
+
/*
* Insert the new node into the hash.
* Add a reference to the lower node.
