xref: /netbsd-src/sys/rump/net/lib/libvirtif/if_virt.c (revision da9817918ec7e88db2912a2882967c7570a83f47)
1 /*	$NetBSD: if_virt.c,v 1.10 2009/05/27 23:41:20 pooka Exp $	*/
2 
3 /*
4  * Copyright (c) 2008 Antti Kantee.  All Rights Reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS
16  * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
17  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
18  * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
21  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25  * SUCH DAMAGE.
26  */
27 
28 #include <sys/cdefs.h>
29 __KERNEL_RCSID(0, "$NetBSD: if_virt.c,v 1.10 2009/05/27 23:41:20 pooka Exp $");
30 
31 #include <sys/param.h>
32 #include <sys/condvar.h>
33 #include <sys/fcntl.h>
34 #include <sys/kmem.h>
35 #include <sys/kthread.h>
36 #include <sys/mutex.h>
37 #include <sys/sockio.h>
38 #include <sys/socketvar.h>
39 
40 #include <net/if.h>
41 #include <net/if_ether.h>
42 #include <net/if_tap.h>
43 
44 #include <netinet/in.h>
45 #include <netinet/in_var.h>
46 
47 #include <rump/rump.h>
48 #include <rump/rumpuser.h>
49 
50 #include "rump_private.h"
51 #include "rump_net_private.h"
52 
53 /*
54  * Virtual interface for userspace purposes.  Uses tap(4) to
55  * interface with the kernel and just simply shovels data
56  * to/from /dev/tap.
57  */
58 
59 #define VIRTIF_BASE "virt"
60 
61 static int	virtif_init(struct ifnet *);
62 static int	virtif_ioctl(struct ifnet *, u_long, void *);
63 static void	virtif_start(struct ifnet *);
64 static void	virtif_stop(struct ifnet *, int);
65 
66 struct virtif_sc {
67 	struct ethercom sc_ec;
68 	int sc_tapfd;
69 	kmutex_t sc_sendmtx;
70 	kcondvar_t sc_sendcv;
71 };
72 
73 static void virtif_worker(void *);
74 static void virtif_sender(void *);
75 
76 #if 0
77 /*
78  * Create a socket and call ifioctl() to configure the interface.
79  * This trickles down to virtif_ioctl().
80  */
81 static int
82 configaddr(struct ifnet *ifp, struct ifaliasreq *ia)
83 {
84 	struct socket *so;
85 	int error;
86 
87 	strcpy(ia->ifra_name, ifp->if_xname);
88 	error = socreate(ia->ifra_addr.sa_family, &so, SOCK_DGRAM,
89 	    0, curlwp, NULL);
90 	if (error)
91 		return error;
92 	error = ifioctl(so, SIOCAIFADDR, ia, curlwp);
93 	soclose(so);
94 
95 	return error;
96 }
97 #endif
98 
99 int
100 rump_virtif_create(int num)
101 {
102 	struct virtif_sc *sc;
103 	struct ifnet *ifp;
104 	uint8_t enaddr[ETHER_ADDR_LEN] = { 0xb2, 0x0a, 0x00, 0x0b, 0x0e, 0x01 };
105 	char tapdev[16];
106 	int fd, error;
107 
108 	snprintf(tapdev, sizeof(tapdev), "/dev/tap%d", num);
109 	fd = rumpuser_open(tapdev, O_RDWR, &error);
110 	if (fd == -1) {
111 		printf("virtif_create: can't open /dev/tap %d\n", error);
112 		return error;
113 	}
114 	KASSERT(num < 0x100);
115 	enaddr[2] = arc4random() & 0xff;
116 	enaddr[5] = num;
117 
118 	sc = kmem_zalloc(sizeof(*sc), KM_SLEEP);
119 	sc->sc_tapfd = fd;
120 
121 	ifp = &sc->sc_ec.ec_if;
122 	sprintf(ifp->if_xname, "%s%d", VIRTIF_BASE, num);
123 	ifp->if_softc = sc;
124 	ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST;
125 	ifp->if_init = virtif_init;
126 	ifp->if_ioctl = virtif_ioctl;
127 	ifp->if_start = virtif_start;
128 	ifp->if_stop = virtif_stop;
129 
130 	mutex_init(&sc->sc_sendmtx, MUTEX_DEFAULT, IPL_NONE);
131 	cv_init(&sc->sc_sendcv, "virtsnd");
132 
133 	if_attach(ifp);
134 	ether_ifattach(ifp, enaddr);
135 
136 	return 0;
137 }
138 
139 static int
140 virtif_init(struct ifnet *ifp)
141 {
142 	int rv;
143 
144 	if (rump_threads) {
145 		rv = kthread_create(PRI_NONE, 0, NULL, virtif_worker, ifp,
146 		    NULL, "virtifi");
147 		/* XXX: should do proper cleanup */
148 		if (rv) {
149 			panic("if_virt: can't create worker");
150 		}
151 		rv = kthread_create(PRI_NONE, 0, NULL, virtif_sender, ifp,
152 		    NULL, "virtifs");
153 		if (rv) {
154 			panic("if_virt: can't create sender");
155 		}
156 	} else {
157 		printf("WARNING: threads not enabled, receive NOT working\n");
158 	}
159 	ifp->if_flags |= IFF_RUNNING;
160 
161 	return 0;
162 }
163 
164 static int
165 virtif_ioctl(struct ifnet *ifp, u_long cmd, void *data)
166 {
167 	int s, rv;
168 
169 	s = splnet();
170 	rv = ether_ioctl(ifp, cmd, data);
171 	if (rv == ENETRESET)
172 		rv = 0;
173 	splx(s);
174 
175 	return rv;
176 }
177 
178 /* just send everything in-context */
179 static void
180 virtif_start(struct ifnet *ifp)
181 {
182 	struct virtif_sc *sc = ifp->if_softc;
183 
184 	mutex_enter(&sc->sc_sendmtx);
185 	cv_signal(&sc->sc_sendcv);
186 	mutex_exit(&sc->sc_sendmtx);
187 }
188 
189 static void
190 virtif_stop(struct ifnet *ifp, int disable)
191 {
192 
193 	panic("%s: unimpl", __func__);
194 }
195 
196 static void
197 virtif_worker(void *arg)
198 {
199 	struct ifnet *ifp = arg;
200 	struct virtif_sc *sc = ifp->if_softc;
201 	struct mbuf *m;
202 	size_t plen = ETHER_MAX_LEN_JUMBO+1;
203 	ssize_t n;
204 	int error;
205 
206 	for (;;) {
207 		m = m_gethdr(M_WAIT, MT_DATA);
208 		MEXTMALLOC(m, plen, M_WAIT);
209 
210 		n = rumpuser_read(sc->sc_tapfd, mtod(m, void *), plen, &error);
211 		KASSERT(n < ETHER_MAX_LEN_JUMBO);
212 		if (n <= 0) {
213 			m_freem(m);
214 			break;
215 		}
216 		m->m_len = m->m_pkthdr.len = n;
217 		m->m_pkthdr.rcvif = ifp;
218 		ether_input(ifp, m);
219 	}
220 
221 	panic("virtif_workin is a lazy boy %d\n", error);
222 }
223 
224 static void
225 virtif_sender(void *arg)
226 {
227 	struct ifnet *ifp = arg;
228 	struct virtif_sc *sc = ifp->if_softc;
229 	struct mbuf *m, *m0;
230 	struct rumpuser_iovec io[16];
231 	int i, error;
232 
233 	mutex_enter(&sc->sc_sendmtx);
234 	for (;;) {
235 		IF_DEQUEUE(&ifp->if_snd, m0);
236 		if (!m0) {
237 			cv_wait(&sc->sc_sendcv, &sc->sc_sendmtx);
238 			continue;
239 		}
240 		mutex_exit(&sc->sc_sendmtx);
241 
242 		m = m0;
243 		for (i = 0; i < 16 && m; i++) {
244 			io[i].iov_base = mtod(m, void *);
245 			io[i].iov_len = m->m_len;
246 			m = m->m_next;
247 		}
248 		if (i == 16)
249 			panic("lazy bum");
250 		rumpuser_writev(sc->sc_tapfd, io, i, &error);
251 		m_freem(m0);
252 		mutex_enter(&sc->sc_sendmtx);
253 	}
254 
255 	mutex_exit(softnet_lock);
256 }
257 
258 /*
259  * dummyif is a nada-interface.
260  * As it requires nothing external, it can be used for testing
261  * interface configuration.
262  */
263 static int	dummyif_init(struct ifnet *);
264 static void	dummyif_start(struct ifnet *);
265 
266 void
267 rump_dummyif_create()
268 {
269 	struct ifnet *ifp;
270 	struct ethercom *ec;
271 	uint8_t enaddr[ETHER_ADDR_LEN] = { 0xb2, 0x0a, 0x00, 0x0b, 0x0e, 0x01 };
272 
273 	enaddr[2] = arc4random() & 0xff;
274 	enaddr[5] = arc4random() & 0xff;
275 
276 	ec = kmem_zalloc(sizeof(*ec), KM_SLEEP);
277 
278 	ifp = &ec->ec_if;
279 	strlcpy(ifp->if_xname, "dummy0", sizeof(ifp->if_xname));
280 	ifp->if_softc = ifp;
281 	ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST;
282 	ifp->if_init = dummyif_init;
283 	ifp->if_ioctl = virtif_ioctl;
284 	ifp->if_start = dummyif_start;
285 
286 	if_attach(ifp);
287 	ether_ifattach(ifp, enaddr);
288 }
289 
290 static int
291 dummyif_init(struct ifnet *ifp)
292 {
293 
294 	ifp->if_flags |= IFF_RUNNING;
295 	return 0;
296 }
297 
298 static void
299 dummyif_start(struct ifnet *ifp)
300 {
301 
302 }
303