From owner-svn-src-all@FreeBSD.ORG  Tue Sep  8 15:51:40 2009
Return-Path: <owner-svn-src-all@FreeBSD.ORG>
Delivered-To: svn-src-all@freebsd.org
Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34])
	by hub.freebsd.org (Postfix) with ESMTP id 9BBB6106568F;
	Tue,  8 Sep 2009 15:51:40 +0000 (UTC) (envelope-from pjd@FreeBSD.org)
Received: from svn.freebsd.org (svn.freebsd.org [IPv6:2001:4f8:fff6::2c])
	by mx1.freebsd.org (Postfix) with ESMTP id 89BBC8FC19;
	Tue,  8 Sep 2009 15:51:40 +0000 (UTC)
Received: from svn.freebsd.org (localhost [127.0.0.1])
	by svn.freebsd.org (8.14.3/8.14.3) with ESMTP id n88Fperw052402;
	Tue, 8 Sep 2009 15:51:40 GMT (envelope-from pjd@svn.freebsd.org)
Received: (from pjd@localhost)
	by svn.freebsd.org (8.14.3/8.14.3/Submit) id n88Fpeta052400;
	Tue, 8 Sep 2009 15:51:40 GMT (envelope-from pjd@svn.freebsd.org)
Message-Id: <200909081551.n88Fpeta052400@svn.freebsd.org>
From: Pawel Jakub Dawidek <pjd@FreeBSD.org>
Date: Tue, 8 Sep 2009 15:51:40 +0000 (UTC)
To: src-committers@freebsd.org, svn-src-all@freebsd.org,
	svn-src-head@freebsd.org
X-SVN-Group: head
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
Cc: 
Subject: svn commit: r196980 -
	head/sys/cddl/contrib/opensolaris/uts/common/fs/zfs
X-BeenThere: svn-src-all@freebsd.org
X-Mailman-Version: 2.1.5
Precedence: list
List-Id: "SVN commit messages for the entire src tree \(except for &quot;
	user&quot; and &quot; projects&quot; \)" <svn-src-all.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/listinfo/svn-src-all>,
	<mailto:svn-src-all-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/svn-src-all>
List-Post: <mailto:svn-src-all@freebsd.org>
List-Help: <mailto:svn-src-all-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/svn-src-all>,
	<mailto:svn-src-all-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Tue, 08 Sep 2009 15:51:40 -0000

Author: pjd
Date: Tue Sep  8 15:51:40 2009
New Revision: 196980
URL: http://svn.freebsd.org/changeset/base/196980

Log:
  When we automatically mount snapshot we want to return vnode of the mount point
  from the lookup and not covered vnode. This is one of the fixes for using .zfs/
  over NFS.
  
  MFC after:	1 week

Modified:
  head/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zfs_ctldir.c

Modified: head/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zfs_ctldir.c
==============================================================================
--- head/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zfs_ctldir.c	Tue Sep  8 15:42:55 2009	(r196979)
+++ head/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zfs_ctldir.c	Tue Sep  8 15:51:40 2009	(r196980)
@@ -882,9 +882,25 @@ domount:
 	    dvp->v_vfsp->mnt_stat.f_mntonname, nm);
 	err = domount(curthread, *vpp, "zfs", mountpoint, snapname, 0);
 	kmem_free(mountpoint, mountpoint_len);
-	/* FreeBSD: This line was moved from below to avoid a lock recursion. */
-	if (err == 0)
-		vn_lock(*vpp, LK_EXCLUSIVE | LK_RETRY);
+	if (err == 0) {
+		vnode_t *mvp;
+
+		ASSERT((*vpp)->v_mountedhere != NULL);
+		err = VFS_ROOT((*vpp)->v_mountedhere, LK_EXCLUSIVE, &mvp);
+		ASSERT(err == 0);
+		VN_RELE(*vpp);
+		*vpp = mvp;
+
+		/*
+		 * Fix up the root vnode mounted on .zfs/snapshot/<snapname>.
+		 *
+		 * This is where we lie about our v_vfsp in order to
+		 * make .zfs/snapshot/<snapname> accessible over NFS
+		 * without requiring manual mounts of <snapname>.
+		 */
+		ASSERT(VTOZ(*vpp)->z_zfsvfs != zfsvfs);
+		VTOZ(*vpp)->z_zfsvfs->z_parent = zfsvfs;
+	}
 	mutex_exit(&sdp->sd_lock);
 	/*
 	 * If we had an error, drop our hold on the vnode and