xref: /freebsd/sys/net/if_dead.c (revision 595e514d0df2bac5b813d35f83e32875dbf16a83)
1 /*-
2  * Copyright (c) 2009 Robert N. M. Watson
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  */
26 
27 /*
28  * When an interface has been detached but not yet freed, we set the various
29  * ifnet function pointers to "ifdead" versions.  This prevents unexpected
30  * calls from the network stack into the device driver after if_detach() has
31  * returned.
32  */
33 
34 #include <sys/cdefs.h>
35 __FBSDID("$FreeBSD$");
36 
37 #include <sys/param.h>
38 #include <sys/mbuf.h>
39 #include <sys/socket.h>
40 
41 #include <net/if.h>
42 #include <net/if_var.h>
43 
44 static int
45 ifdead_output(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *sa,
46     struct route *ro)
47 {
48 
49 	m_freem(m);
50 	return (ENXIO);
51 }
52 
53 static void
54 ifdead_input(struct ifnet *ifp, struct mbuf *m)
55 {
56 
57 	m_freem(m);
58 }
59 
60 static void
61 ifdead_start(struct ifnet *ifp)
62 {
63 
64 }
65 
66 static int
67 ifdead_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data)
68 {
69 
70 	return (ENXIO);
71 }
72 
73 static int
74 ifdead_resolvemulti(struct ifnet *ifp, struct sockaddr **llsa,
75     struct sockaddr *sa)
76 {
77 
78 	*llsa = NULL;
79 	return (ENXIO);
80 }
81 
82 static void
83 ifdead_qflush(struct ifnet *ifp)
84 {
85 
86 }
87 
88 static int
89 ifdead_transmit(struct ifnet *ifp, struct mbuf *m)
90 {
91 
92 	m_freem(m);
93 	return (ENXIO);
94 }
95 
96 void
97 if_dead(struct ifnet *ifp)
98 {
99 
100 	ifp->if_output = ifdead_output;
101 	ifp->if_input = ifdead_input;
102 	ifp->if_start = ifdead_start;
103 	ifp->if_ioctl = ifdead_ioctl;
104 	ifp->if_resolvemulti = ifdead_resolvemulti;
105 	ifp->if_qflush = ifdead_qflush;
106 	ifp->if_transmit = ifdead_transmit;
107 }
108