From 81f78d997d8796c5dad7982048843ed8bfa0cbbf Mon Sep 17 00:00:00 2001
From: Rick Macklem <rmacklem@FreeBSD.org>
Date: Mon, 3 Jan 2011 00:33:32 +0000
Subject: [PATCH] Modify the experimental NFSv4 server so that the lookup ops
 return a locked vnode. This ensures that the associated mount point will
 always be valid for the code that follows the operation. Also add a couple of
 additional checks for non-error to the other functions that create file
 objects.

MFC after:	2 weeks
---
 sys/fs/nfsserver/nfs_nfsdserv.c   | 20 ++++++++------------
 sys/fs/nfsserver/nfs_nfsdsocket.c |  6 +++++-
 2 files changed, 13 insertions(+), 13 deletions(-)

diff --git a/sys/fs/nfsserver/nfs_nfsdserv.c b/sys/fs/nfsserver/nfs_nfsdserv.c
index c56475477a86..f3eb52da35d3 100644
--- a/sys/fs/nfsserver/nfs_nfsdserv.c
+++ b/sys/fs/nfsserver/nfs_nfsdserv.c
@@ -470,12 +470,10 @@ nfsrvd_lookup(struct nfsrv_descript *nd, __unused int isdgram,
 	nd->nd_repstat = nfsvno_getfh(vp, fhp, p);
 	if (!(nd->nd_flag & ND_NFSV4) && !nd->nd_repstat)
 		nd->nd_repstat = nfsvno_getattr(vp, &nva, nd->nd_cred, p, 1);
-	if (vpp) {
-		NFSVOPUNLOCK(vp, 0, p);
+	if (vpp != NULL && nd->nd_repstat == 0)
 		*vpp = vp;
-	} else {
+	else
 		vput(vp);
-	}
 	if (dirp) {
 		if (nd->nd_flag & ND_NFSV3)
 			dattr_ret = nfsvno_getattr(dirp, &dattr, nd->nd_cred,
@@ -1218,12 +1216,11 @@ nfsrvd_mknod(struct nfsrv_descript *nd, __unused int isdgram,
 		if ((nd->nd_flag & ND_NFSV3) && !nd->nd_repstat)
 			nd->nd_repstat = nfsvno_getattr(vp, &nva, nd->nd_cred,
 			    p, 1);
-		if (vpp) {
-			NFSVOPUNLOCK(vp, 0, p);
+		if (vpp != NULL && nd->nd_repstat == 0) {
+			VOP_UNLOCK(vp, 0);
 			*vpp = vp;
-		} else {
+		} else
 			vput(vp);
-		}
 	}
 
 	diraft_ret = nfsvno_getattr(dirp, &diraft, nd->nd_cred, p, 0);
@@ -1706,12 +1703,11 @@ nfsrvd_symlinksub(struct nfsrv_descript *nd, struct nameidata *ndp,
 				nd->nd_repstat = nfsvno_getattr(ndp->ni_vp,
 				    nvap, nd->nd_cred, p, 1);
 		}
-		if (vpp) {
-			NFSVOPUNLOCK(ndp->ni_vp, 0, p);
+		if (vpp != NULL && nd->nd_repstat == 0) {
+			VOP_UNLOCK(ndp->ni_vp, 0);
 			*vpp = ndp->ni_vp;
-		} else {
+		} else
 			vput(ndp->ni_vp);
-		}
 	}
 	if (dirp) {
 		*diraft_retp = nfsvno_getattr(dirp, diraftp, nd->nd_cred, p, 0);
diff --git a/sys/fs/nfsserver/nfs_nfsdsocket.c b/sys/fs/nfsserver/nfs_nfsdsocket.c
index fb6a87cd377e..68cc05a7407f 100644
--- a/sys/fs/nfsserver/nfs_nfsdsocket.c
+++ b/sys/fs/nfsserver/nfs_nfsdsocket.c
@@ -861,10 +861,14 @@ nfsrvd_compound(struct nfsrv_descript *nd, int isdgram,
 					    nfsvno_lockvfs(mp);
 				    }
 			    }
+			    if (op == NFSV4OP_LOOKUP || op == NFSV4OP_LOOKUPP)
+				    /* Lookup ops return a locked vnode */
+				    VOP_UNLOCK(nvp, 0);
 			    if (!nd->nd_repstat) {
 				    vrele(vp);
 				    vp = nvp;
-			    }
+			    } else
+				    vrele(nvp);
 			}
 			if (nfsv4_opflag[op].modifyfs)
 				NFS_ENDWRITE(mp);