xref: /netbsd-src/sys/miscfs/deadfs/dead_vfsops.c (revision 26784725eeed8e5fc5898ec384aab2af43e2e264)
1 /*	$NetBSD: dead_vfsops.c,v 1.13 2022/10/26 23:39:43 riastradh Exp $	*/
2 
3 /*-
4  * Copyright (c) 2014 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Juergen Hannken-Illjes.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 #include <sys/cdefs.h>
33 __KERNEL_RCSID(0, "$NetBSD: dead_vfsops.c,v 1.13 2022/10/26 23:39:43 riastradh Exp $");
34 
35 #include <sys/param.h>
36 #include <sys/systm.h>
37 #include <sys/vnode.h>
38 #include <sys/mount.h>
39 
40 #include <miscfs/deadfs/deadfs.h>
41 #include <miscfs/specfs/specdev.h>
42 
43 VFS_PROTOS(dead);
44 
45 static void dead_panic(void);
46 
47 static const struct vnodeopv_desc * const dead_vnodeopv_descs[] = {
48 	&dead_vnodeop_opv_desc,
49 	NULL
50 };
51 
52 struct mount *dead_rootmount;
53 
54 struct vfsops dead_vfsops = {
55 	.vfs_name = "dead",
56 	.vfs_min_mount_data = 0,
57 	.vfs_mount = (void *)dead_panic,
58 	.vfs_start = (void *)dead_panic,
59 	.vfs_unmount = (void *)dead_panic,
60 	.vfs_root = (void *)dead_panic,
61 	.vfs_quotactl = (void *)dead_panic,
62 	.vfs_statvfs = (void *)eopnotsupp,
63 	.vfs_sync = (void *)dead_panic,
64 	.vfs_vget = (void *)dead_panic,
65 	.vfs_loadvnode = (void *)dead_panic,
66 	.vfs_newvnode = dead_newvnode,
67 	.vfs_fhtovp = (void *)dead_panic,
68 	.vfs_vptofh = (void *)eopnotsupp,
69 	.vfs_init = (void *)dead_panic,
70 	.vfs_reinit = (void *)dead_panic,
71 	.vfs_done = (void *)dead_panic,
72 	.vfs_mountroot = (void *)dead_panic,
73 	.vfs_snapshot = (void *)dead_panic,
74 	.vfs_extattrctl = (void *)dead_panic,
75 	.vfs_suspendctl = (void *)dead_panic,
76 	.vfs_renamelock_enter = (void *)dead_panic,
77 	.vfs_renamelock_exit = (void *)dead_panic,
78 	.vfs_fsync = (void *)eopnotsupp,
79 	.vfs_opv_descs = dead_vnodeopv_descs
80 };
81 
82 static void
dead_panic(void)83 dead_panic(void)
84 {
85 
86 	panic("dead fs operation used");
87 }
88 
89 /*
90  * Create a new anonymous device vnode.
91  */
92 int
dead_newvnode(struct mount * mp,struct vnode * dvp,struct vnode * vp,struct vattr * vap,kauth_cred_t cred,void * extra,size_t * key_len,const void ** new_key)93 dead_newvnode(struct mount *mp, struct vnode *dvp, struct vnode *vp,
94     struct vattr *vap, kauth_cred_t cred, void *extra,
95     size_t *key_len, const void **new_key)
96 {
97 
98 	KASSERT(mp == dead_rootmount);
99 	KASSERT(dvp == NULL);
100 	KASSERT(vap->va_type == VCHR || vap->va_type == VBLK);
101 	KASSERT(vap->va_rdev != VNOVAL);
102 
103 	vp->v_tag = VT_NON;
104 	vp->v_type = vap->va_type;
105 	vp->v_op = spec_vnodeop_p;
106 	vp->v_vflag |= VV_MPSAFE;
107 	uvm_vnp_setsize(vp, 0);
108 	spec_node_init(vp, vap->va_rdev);
109 
110 	*key_len = 0;
111 	*new_key = NULL;
112 
113 	return 0;
114 }
115