From cf7aa80bbde7683484074413e2cb1bf78616afe1 Mon Sep 17 00:00:00 2001
From: Andriy Gapon <avg@FreeBSD.org>
Date: Mon, 16 May 2016 07:24:30 +0000
Subject: [PATCH] zfsctl_ops_snapshot: remove methods should never be called

We pretend that snapshots mounted under .zfs are part of the original
filesystem and we try very hard to hide vnodes on top of which the snapshots
are mounted.  Given that I believe that the removed operations should
never be called.  They might have been called previously because
of issues fixed in r299906, r299908 and r299913.

MFC after:	5 weeks
---
 .../uts/common/fs/zfs/zfs_ctldir.c            | 96 -------------------
 1 file changed, 96 deletions(-)

diff --git a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zfs_ctldir.c b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zfs_ctldir.c
index d30777836fe..88c2e2760eb 100644
--- a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zfs_ctldir.c
+++ b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zfs_ctldir.c
@@ -1521,99 +1521,6 @@ zfsctl_snapshot_reclaim(ap)
 
 }
 
-static int
-zfsctl_traverse_begin(vnode_t **vpp, int lktype)
-{
-
-	VN_HOLD(*vpp);
-	/* Snapshot should be already mounted, but just in case. */
-	if (vn_mountedvfs(*vpp) == NULL)
-		return (ENOENT);
-	return (traverse(vpp, lktype));
-}
-
-static void
-zfsctl_traverse_end(vnode_t *vp, int err)
-{
-
-	if (err == 0)
-		vput(vp);
-	else
-		VN_RELE(vp);
-}
-
-static int
-zfsctl_snapshot_getattr(ap)
-	struct vop_getattr_args /* {
-		struct vnode *a_vp;
-		struct vattr *a_vap;
-		struct ucred *a_cred;
-	} */ *ap;
-{
-	vnode_t *vp = ap->a_vp;
-	int err;
-
-	err = zfsctl_traverse_begin(&vp, LK_SHARED | LK_RETRY);
-	if (err == 0)
-		err = VOP_GETATTR(vp, ap->a_vap, ap->a_cred);
-	zfsctl_traverse_end(vp, err);
-	return (err);
-}
-
-static int
-zfsctl_snapshot_fid(ap)
-	struct vop_fid_args /* {
-		struct vnode *a_vp;
-		struct fid *a_fid;
-	} */ *ap;
-{
-	vnode_t *vp = ap->a_vp;
-	int err;
-
-	err = zfsctl_traverse_begin(&vp, LK_SHARED | LK_RETRY);
-	if (err == 0)
-		err = VOP_VPTOFH(vp, (void *)ap->a_fid);
-	zfsctl_traverse_end(vp, err);
-	return (err);
-}
-
-static int
-zfsctl_snapshot_lookup(ap)
-	struct vop_lookup_args /* {
-		struct vnode *a_dvp;
-		struct vnode **a_vpp;
-		struct componentname *a_cnp;
-	} */ *ap;
-{
-	vnode_t *dvp = ap->a_dvp;
-	vnode_t **vpp = ap->a_vpp;
-	struct componentname *cnp = ap->a_cnp;
-	cred_t *cr = ap->a_cnp->cn_cred;
-	zfsvfs_t *zfsvfs = dvp->v_vfsp->vfs_data;
-	int error;
-
-	if (cnp->cn_namelen != 2 || cnp->cn_nameptr[0] != '.' ||
-	    cnp->cn_nameptr[1] != '.') {
-		return (ENOENT);
-	}
-
-	ASSERT(dvp->v_type == VDIR);
-	ASSERT(zfsvfs->z_ctldir != NULL);
-
-	error = zfsctl_root_lookup(zfsvfs->z_ctldir, "snapshot", vpp,
-	    NULL, 0, NULL, cr, NULL, NULL, NULL);
-	if (error == 0) {
-		int ltype = VOP_ISLOCKED(dvp);
-		VN_HOLD(*vpp);
-		VOP_UNLOCK(dvp, 0);
-		vn_lock(*vpp, LK_EXCLUSIVE | LK_RETRY);
-		VN_RELE(*vpp);
-		vn_lock(dvp, ltype | LK_RETRY);
-	}
-
-	return (error);
-}
-
 static int
 zfsctl_snapshot_vptocnp(struct vop_vptocnp_args *ap)
 {
@@ -1663,10 +1570,7 @@ zfsctl_snapshot_vptocnp(struct vop_vptocnp_args *ap)
 static struct vop_vector zfsctl_ops_snapshot = {
 	.vop_default =	&default_vnodeops,
 	.vop_inactive =	VOP_NULL,
-	.vop_lookup =	zfsctl_snapshot_lookup,
 	.vop_reclaim =	zfsctl_snapshot_reclaim,
-	.vop_getattr =	zfsctl_snapshot_getattr,
-	.vop_fid =	zfsctl_snapshot_fid,
 	.vop_vptocnp =	zfsctl_snapshot_vptocnp,
 };