From: Derrick Brashear <shadow@dementia.org>
Date: Sat, 11 Jan 2003 07:44:19 +0000 (+0000)
Subject: STABLE12-vol-package-avoid-race-on-invalidating-hashed-vnode-20030111
X-Git-Tag: openafs-stable-1_2_9~86
X-Git-Url: https://git.michaelhowe.org/gitweb/?a=commitdiff_plain;h=1b135c8d53505ceb674682796258fa0eead12ff8;p=packages%2Fo%2Fopenafs.git

STABLE12-vol-package-avoid-race-on-invalidating-hashed-vnode-20030111


thanks to whichever of jhutz@cmu.edu or cg2v@andrew.cmu.edu (or both)
noticed the race; also deal with wrap problem in VolumeCacheCheck that i
noticed
---

diff --git a/src/vol/vnode.c b/src/vol/vnode.c
index bad05c47c..e9ec600b8 100644
--- a/src/vol/vnode.c
+++ b/src/vol/vnode.c
@@ -634,7 +634,7 @@ Vnode *VGetVnode_r(ec,vp,vnodeNumber,locktype)
     /* Check that the vnode hasn't been removed while we were obtaining
        the lock */
     VNLog(102, 2, vnodeNumber, (afs_int32) vnp);
-    if (vnp->disk.type == vNull) {
+    if ((vnp->disk.type == vNull) || (vnp->cacheCheck == 0)){
 	if (vnp->nUsers-- == 1)
 	    StickOnLruChain_r(vnp,vcp);
 	if (locktype == READ_LOCK)
diff --git a/src/vol/volume.c b/src/vol/volume.c
index 889d9eac9..b150504e4 100644
--- a/src/vol/volume.c
+++ b/src/vol/volume.c
@@ -699,6 +699,9 @@ private Volume *attach2(ec, path, header, partp, isbusy)
     IH_INIT(vp->linkHandle, partp->device, header->parent,
 		   header->linkTable);
     vp->cacheCheck = ++VolumeCacheCheck;
+    /* just in case this ever rolls over */
+    if (!vp->cacheCheck) 
+	vp->cacheCheck = ++VolumeCacheCheck;
     vp->shuttingDown = 0;
     vp->goingOffline = 0;
     vp->nUsers = 1;