xref: /netbsd-src/sys/arch/usermode/dev/if_veth.c (revision 181254a7b1bdde6873432bffef2d2decc4b5c22f)
1 /* $NetBSD: if_veth.c,v 1.14 2020/02/05 07:18:16 skrll Exp $ */
2 
3 /*-
4  * Copyright (c) 2011 Jared D. McNeill <jmcneill@invisible.ca>
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
17  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
18  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
19  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
20  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
21  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
22  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
23  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
24  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
25  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
26  * POSSIBILITY OF SUCH DAMAGE.
27  */
28 
29 #include <sys/cdefs.h>
30 __KERNEL_RCSID(0, "$NetBSD: if_veth.c,v 1.14 2020/02/05 07:18:16 skrll Exp $");
31 
32 #include <sys/param.h>
33 #include <sys/proc.h>
34 #include <sys/systm.h>
35 #include <sys/kernel.h>
36 #include <sys/mbuf.h>
37 #include <sys/socket.h>
38 #include <sys/device.h>
39 
40 #include <net/if.h>
41 #include <net/if_ether.h>
42 #include <net/if_media.h>
43 
44 #include <net/bpf.h>
45 
46 #include <machine/mainbus.h>
47 #include <machine/thunk.h>
48 
49 static int	veth_match(device_t, cfdata_t, void *);
50 static void	veth_attach(device_t, device_t, void *);
51 static bool	veth_shutdown(device_t, int);
52 
53 static int	veth_init(struct ifnet *);
54 static void	veth_start(struct ifnet *);
55 static void	veth_stop(struct ifnet *, int);
56 static void	veth_watchdog(struct ifnet *);
57 static int	veth_ioctl(struct ifnet *, u_long, void *);
58 
59 static int	veth_rx(void *);
60 static void	veth_softrx(void *);
61 static void	veth_softtx(void *);
62 
63 static int	veth_ifmedia_change(struct ifnet *);
64 static void	veth_ifmedia_status(struct ifnet *, struct ifmediareq *);
65 
66 #ifdef VETH_DEBUG
67 #define vethprintf printf
68 #else
69 static inline void vethprintf(const char *fmt, ...) { }
70 #endif
71 
72 struct veth_softc {
73 	device_t		sc_dev;
74 	struct ethercom		sc_ec;
75 	struct ifmedia		sc_ifmedia;
76 	int			sc_tapfd;
77 	uint8_t			sc_eaddr[ETHER_ADDR_LEN];
78 	uint8_t			sc_rx_buf[4096 + 65536];
79 	uint8_t			sc_tx_buf[4096 + 65536];
80 	void			*sc_rx_ih;
81 	void			*sc_rx_intr;
82 	void			*sc_tx_intr;
83 };
84 
85 CFATTACH_DECL_NEW(veth, sizeof(struct veth_softc),
86     veth_match, veth_attach, NULL, NULL);
87 
88 static int
89 veth_match(device_t parent, cfdata_t match, void *opaque)
90 {
91 	struct thunkbus_attach_args *taa = opaque;
92 
93 	if (taa->taa_type != THUNKBUS_TYPE_VETH)
94 		return 0;
95 
96 	return 1;
97 }
98 
99 static void
100 veth_attach(device_t parent, device_t self, void *opaque)
101 {
102 	struct veth_softc *sc = device_private(self);
103 	struct thunkbus_attach_args *taa = opaque;
104 	struct ifnet *ifp = &sc->sc_ec.ec_if;
105 	int rv;
106 
107 	sc->sc_dev = self;
108 
109 	pmf_device_register1(self, NULL, NULL, veth_shutdown);
110 
111 	sc->sc_tapfd = thunk_open_tap(taa->u.veth.device);
112 	if (sc->sc_tapfd == -1) {
113 		aprint_error(": couldn't open %s: %d\n",
114 		    taa->u.veth.device, thunk_geterrno());
115 		return;
116 	}
117 	if (ether_aton_r(sc->sc_eaddr, sizeof(sc->sc_eaddr),
118 	    taa->u.veth.eaddr) != 0) {
119 		aprint_error(": couldn't parse hw address '%s'\n",
120 		    taa->u.veth.eaddr);
121 		return;
122 	}
123 
124 	aprint_naive("\n");
125 	aprint_normal(": Virtual Ethernet (device = %s)\n", taa->u.veth.device);
126 
127 	aprint_normal_dev(self, "Ethernet address %s\n",
128 	    ether_sprintf(sc->sc_eaddr));
129 
130 	strlcpy(ifp->if_xname, device_xname(self), IFNAMSIZ);
131 	ifp->if_softc = sc;
132 	ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST;
133 	ifp->if_ioctl = veth_ioctl;
134 	ifp->if_watchdog = veth_watchdog;
135 	ifp->if_start = veth_start;
136 	ifp->if_init = veth_init;
137 	ifp->if_stop = veth_stop;
138 	IFQ_SET_MAXLEN(&ifp->if_snd, IFQ_MAXLEN);
139 	IFQ_SET_READY(&ifq->if_snd);
140 
141 	rv = if_initialize(ifp);
142 	if (rv != 0) {
143 		aprint_error_dev(self, "if_initialize failed(%d)\n", rv);
144 		thunk_close(sc->sc_tapfd);
145 		pmf_device_deregister(self);
146 		return; /* Error */
147 	}
148 	ether_ifattach(ifp, sc->sc_eaddr);
149 	if_register(ifp);
150 
151 	/* Initialize ifmedia structures. */
152 	sc->sc_ec.ec_ifmedia = &sc->sc_ifmedia;
153 	ifmedia_init(&sc->sc_ifmedia, 0,
154 	    veth_ifmedia_change, veth_ifmedia_status);
155 	ifmedia_add(&sc->sc_ifmedia, IFM_ETHER | IFM_100_TX, 0, NULL);
156 	ifmedia_set(&sc->sc_ifmedia, IFM_ETHER | IFM_100_TX);
157 
158 	sc->sc_rx_intr = softint_establish(SOFTINT_NET, veth_softrx, sc);
159 	if (sc->sc_rx_intr == NULL)
160 		panic("couldn't establish veth rx softint");
161 	sc->sc_tx_intr = softint_establish(SOFTINT_NET, veth_softtx, sc);
162 	if (sc->sc_tx_intr == NULL)
163 		panic("couldn't establish veth tx softint");
164 
165 	thunk_setown(sc->sc_tapfd);
166 
167 	sc->sc_rx_ih = sigio_intr_establish(veth_rx, sc);
168 	if (sc->sc_rx_ih == NULL)
169 		panic("couldn't establish veth rx interrupt");
170 }
171 
172 static bool
173 veth_shutdown(device_t self, int flags)
174 {
175 	struct veth_softc *sc = device_private(self);
176 
177 	if (sc->sc_tapfd != -1)
178 		thunk_close(sc->sc_tapfd);
179 
180 	return true;
181 }
182 
183 static int
184 veth_init(struct ifnet *ifp)
185 {
186 	vethprintf("%s: %s flags=%x\n", __func__, ifp->if_xname, ifp->if_flags);
187 
188 	veth_stop(ifp, 0);
189 
190 	ifp->if_flags |= IFF_RUNNING;
191 	ifp->if_flags &= ~IFF_OACTIVE;
192 
193 	return 0;
194 }
195 
196 static int
197 veth_rx(void *priv)
198 {
199 	struct veth_softc *sc = priv;
200 
201 	softint_schedule(sc->sc_rx_intr);
202 	return 0;
203 }
204 
205 static void
206 veth_softrx(void *priv)
207 {
208 	struct veth_softc *sc = priv;
209 	struct ifnet *ifp = &sc->sc_ec.ec_if;
210 	struct mbuf *m;
211 	ssize_t len;
212 	int s, avail;
213 
214 	for (;;) {
215 		avail = thunk_pollin_tap(sc->sc_tapfd, 0);
216 		if (avail == 0)
217 			break;
218 
219 		len = thunk_read(sc->sc_tapfd, sc->sc_rx_buf,
220 		    uimin(avail, sizeof(sc->sc_rx_buf)));
221 		vethprintf("%s: read returned %d\n", __func__, len);
222 		if (len == -1)
223 			panic("read() from tap failed");
224 
225 		MGETHDR(m, M_DONTWAIT, MT_DATA);
226 		if (m == NULL) {
227 			vethprintf("MGETHDR failed (input error)\n");
228 			if_statinc(ifp, if_ierrors);
229 			continue;
230 		}
231 		if (len > MHLEN) {
232 			MCLGET(m, M_DONTWAIT);
233 			if ((m->m_flags & M_EXT) == 0) {
234 				m_freem(m);
235 				if_statinc(ifp, if_ierrors);
236 				vethprintf("M_EXT not set (input error)\n");
237 				continue;
238 			}
239 		}
240 		m_set_rcvif(m, ifp);
241 		m->m_pkthdr.len = m->m_len = len;
242 		memcpy(mtod(m, void *), sc->sc_rx_buf, len);
243 
244 		s = splnet();
245 		if_input(ifp, m);
246 		splx(s);
247 	}
248 }
249 
250 static void
251 veth_softtx(void *priv)
252 {
253 	struct veth_softc *sc = priv;
254 	struct ifnet *ifp = &sc->sc_ec.ec_if;
255 	int s;
256 
257 	if (ifp->if_flags & IFF_OACTIVE) {
258 		if (thunk_pollout_tap(sc->sc_tapfd, 0) == 1)
259 			ifp->if_flags &= ~IFF_OACTIVE;
260 	}
261 
262 	s = splnet();
263 	veth_start(ifp);
264 	splx(s);
265 }
266 
267 static void
268 veth_start(struct ifnet *ifp)
269 {
270 	struct veth_softc *sc = ifp->if_softc;
271 	struct mbuf *m0;
272 	ssize_t len;
273 
274 	vethprintf("%s: %s flags=%x\n", __func__, ifp->if_xname, ifp->if_flags);
275 
276 	if ((ifp->if_flags & (IFF_RUNNING | IFF_OACTIVE)) != IFF_RUNNING)
277 		return;
278 
279 	for (;;) {
280 		IFQ_POLL(&ifp->if_snd, m0);
281 		if (m0 == NULL)
282 			break;
283 
284 		if (thunk_pollout_tap(sc->sc_tapfd, 0) != 1) {
285 			printf("queue full\n");
286 			ifp->if_flags |= IFF_OACTIVE;
287 			break;
288 		}
289 
290 		IFQ_DEQUEUE(&ifp->if_snd, m0);
291 		bpf_mtap(ifp, m0, BPF_D_OUT);
292 
293 		m_copydata(m0, 0, m0->m_pkthdr.len, sc->sc_tx_buf);
294 
295 		vethprintf("write %d bytes...\n", m0->m_pkthdr.len);
296 		len = thunk_write(sc->sc_tapfd, sc->sc_tx_buf,
297 		    m0->m_pkthdr.len);
298 		vethprintf("write returned %d\n", len);
299 		if (len > 0)
300 			if_statinc(ifp, if_opackets);
301 		else
302 			if_statinc(ifp, if_oerrors);
303 		m_freem(m0);
304 	}
305 }
306 
307 static void
308 veth_stop(struct ifnet *ifp, int disable)
309 {
310 	vethprintf("%s: %s flags=%x\n", __func__, ifp->if_xname, ifp->if_flags);
311 	ifp->if_timer = 0;
312 	ifp->if_flags &= ~(IFF_RUNNING | IFF_OACTIVE);
313 }
314 
315 static void
316 veth_watchdog(struct ifnet *ifp)
317 {
318 	vethprintf("%s: %s flags=%x\n", __func__, ifp->if_xname, ifp->if_flags);
319 	if_statinc(ifp, if_oerrors);
320 	veth_init(ifp);
321 }
322 
323 static int
324 veth_ioctl(struct ifnet *ifp, u_long cmd, void *data)
325 {
326 	int s, error;
327 
328 	vethprintf("%s: %s flags=%x\n", __func__, ifp->if_xname, ifp->if_flags);
329 
330 	s = splnet();
331 
332 	switch (cmd) {
333 	case SIOCADDMULTI:
334 	case SIOCDELMULTI:
335 		if ((error = ether_ioctl(ifp, cmd, data)) == ENETRESET) {
336 			if (ifp->if_flags & IFF_RUNNING) {
337 				veth_init(ifp);
338 			}
339 			error = 0;
340 		}
341 		break;
342 	default:
343 		error = ether_ioctl(ifp, cmd, data);
344 		break;
345 	}
346 
347 	splx(s);
348 	return error;
349 }
350 
351 static int
352 veth_ifmedia_change(struct ifnet *ifp)
353 {
354 	vethprintf("%s: %s flags=%x\n", __func__, ifp->if_xname, ifp->if_flags);
355 	return 0;
356 }
357 
358 static void
359 veth_ifmedia_status(struct ifnet *ifp, struct ifmediareq *req)
360 {
361 	vethprintf("%s: %s flags=%x\n", __func__, ifp->if_xname, ifp->if_flags);
362 	req->ifm_status |= IFM_ACTIVE | IFM_AVALID;
363 	req->ifm_active = IFM_100_TX | IFM_FDX | IFM_ETHER;
364 }
365