1/* $NetBSD: if_veth.c,v 1.4 2012/01/15 10:51:12 jmcneill 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 1.4 2012/01/15 10:51:12 jmcneill 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
49static int	veth_match(device_t, cfdata_t, void *);
50static void	veth_attach(device_t, device_t, void *);
51static bool	veth_shutdown(device_t, int);
52
53static int	veth_init(struct ifnet *);
54static void	veth_start(struct ifnet *);
55static void	veth_stop(struct ifnet *, int);
56static void	veth_watchdog(struct ifnet *);
57static int	veth_ioctl(struct ifnet *, u_long, void *);
58
59static int	veth_rx(void *);
60static void	veth_softrx(void *);
61static void	veth_softtx(void *);
62
63static int	veth_ifmedia_change(struct ifnet *);
64static void	veth_ifmedia_status(struct ifnet *, struct ifmediareq *);
65
66#ifdef VETH_DEBUG
67#define vethprintf printf
68#else
69static inline void vethprintf(const char *fmt, ...) { }
70#endif
71
72struct 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
85CFATTACH_DECL_NEW(veth, sizeof(struct veth_softc),
86    veth_match, veth_attach, NULL, NULL);
87
88static int
89veth_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
99static void
100veth_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
106	sc->sc_dev = self;
107
108	pmf_device_register1(self, NULL, NULL, veth_shutdown);
109
110	sc->sc_tapfd = thunk_open_tap(taa->u.veth.device);
111	if (sc->sc_tapfd == -1) {
112		aprint_error(": couldn't open %s: %d\n",
113		    taa->u.veth.device, thunk_geterrno());
114		return;
115	}
116	if (ether_aton_r(sc->sc_eaddr, sizeof(sc->sc_eaddr),
117	    taa->u.veth.eaddr) != 0) {
118		aprint_error(": couldn't parse hw address '%s'\n",
119		    taa->u.veth.eaddr);
120		return;
121	}
122
123	aprint_naive("\n");
124	aprint_normal(": Virtual Ethernet (device = %s)\n", taa->u.veth.device);
125
126	aprint_normal_dev(self, "Ethernet address %s\n",
127	    ether_sprintf(sc->sc_eaddr));
128
129	strlcpy(ifp->if_xname, device_xname(self), IFNAMSIZ);
130	ifp->if_softc = sc;
131	ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST;
132	ifp->if_ioctl = veth_ioctl;
133	ifp->if_watchdog = veth_watchdog;
134	ifp->if_start = veth_start;
135	ifp->if_init = veth_init;
136	ifp->if_stop = veth_stop;
137	IFQ_SET_MAXLEN(&ifp->if_snd, IFQ_MAXLEN);
138	IFQ_SET_READY(&ifq->if_snd);
139
140	if_attach(ifp);
141	ether_ifattach(ifp, sc->sc_eaddr);
142
143	ifmedia_init(&sc->sc_ifmedia, 0,
144	    veth_ifmedia_change,
145	    veth_ifmedia_status);
146	ifmedia_add(&sc->sc_ifmedia, IFM_ETHER|IFM_100_TX, 0, NULL);
147	ifmedia_set(&sc->sc_ifmedia, IFM_ETHER|IFM_100_TX);
148
149	sc->sc_rx_intr = softint_establish(SOFTINT_NET, veth_softrx, sc);
150	if (sc->sc_rx_intr == NULL)
151		panic("couldn't establish veth rx softint");
152	sc->sc_tx_intr = softint_establish(SOFTINT_NET, veth_softtx, sc);
153	if (sc->sc_tx_intr == NULL)
154		panic("couldn't establish veth tx softint");
155
156	thunk_setown(sc->sc_tapfd);
157
158	sc->sc_rx_ih = sigio_intr_establish(veth_rx, sc);
159	if (sc->sc_rx_ih == NULL)
160		panic("couldn't establish veth rx interrupt");
161}
162
163static bool
164veth_shutdown(device_t self, int flags)
165{
166	struct veth_softc *sc = device_private(self);
167
168	if (sc->sc_tapfd != -1)
169		thunk_close(sc->sc_tapfd);
170
171	return true;
172}
173
174static int
175veth_init(struct ifnet *ifp)
176{
177	vethprintf("%s: %s flags=%x\n", __func__, ifp->if_xname, ifp->if_flags);
178
179	veth_stop(ifp, 0);
180
181	ifp->if_flags |= IFF_RUNNING;
182	ifp->if_flags &= ~IFF_OACTIVE;
183
184	return 0;
185}
186
187static int
188veth_rx(void *priv)
189{
190	struct veth_softc *sc = priv;
191
192	softint_schedule(sc->sc_rx_intr);
193	return 0;
194}
195
196static void
197veth_softrx(void *priv)
198{
199	struct veth_softc *sc = priv;
200	struct ifnet *ifp = &sc->sc_ec.ec_if;
201	struct mbuf *m;
202	ssize_t len;
203	int s, avail;
204
205	for (;;) {
206		avail = thunk_pollin_tap(sc->sc_tapfd, 0);
207		if (avail == 0)
208			break;
209
210		len = thunk_read(sc->sc_tapfd, sc->sc_rx_buf,
211		    min(avail, sizeof(sc->sc_rx_buf)));
212		vethprintf("%s: read returned %d\n", __func__, len);
213		if (len == -1)
214			panic("read() from tap failed");
215
216		MGETHDR(m, M_DONTWAIT, MT_DATA);
217		if (m == NULL) {
218			vethprintf("MGETHDR failed (input error)\n");
219			++ifp->if_ierrors;
220			continue;
221		}
222		if (len > MHLEN) {
223			MCLGET(m, M_DONTWAIT);
224			if ((m->m_flags & M_EXT) == 0) {
225				m_freem(m);
226				++ifp->if_ierrors;
227				vethprintf("M_EXT not set (input error)\n");
228				continue;
229			}
230		}
231		m->m_pkthdr.rcvif = ifp;
232		m->m_pkthdr.len = m->m_len = len;
233		memcpy(mtod(m, void *), sc->sc_rx_buf, len);
234		++ifp->if_ipackets;
235
236		bpf_mtap(ifp, m);
237
238		s = splnet();
239		ifp->if_input(ifp, m);
240		splx(s);
241	}
242}
243
244static void
245veth_softtx(void *priv)
246{
247	struct veth_softc *sc = priv;
248	struct ifnet *ifp = &sc->sc_ec.ec_if;
249	int s;
250
251	if (ifp->if_flags & IFF_OACTIVE) {
252		if (thunk_pollout_tap(sc->sc_tapfd, 0) == 1)
253			ifp->if_flags &= ~IFF_OACTIVE;
254	}
255
256	s = splnet();
257	veth_start(ifp);
258	splx(s);
259}
260
261static void
262veth_start(struct ifnet *ifp)
263{
264	struct veth_softc *sc = ifp->if_softc;
265	struct mbuf *m0;
266	ssize_t len;
267
268	vethprintf("%s: %s flags=%x\n", __func__, ifp->if_xname, ifp->if_flags);
269
270	if ((ifp->if_flags & (IFF_RUNNING|IFF_OACTIVE)) != IFF_RUNNING)
271		return;
272
273	for (;;) {
274		IFQ_POLL(&ifp->if_snd, m0);
275		if (m0 == NULL)
276			break;
277
278		if (thunk_pollout_tap(sc->sc_tapfd, 0) != 1) {
279			printf("queue full\n");
280			ifp->if_flags |= IFF_OACTIVE;
281			break;
282		}
283
284		IFQ_DEQUEUE(&ifp->if_snd, m0);
285		bpf_mtap(ifp, m0);
286
287		m_copydata(m0, 0, m0->m_pkthdr.len, sc->sc_tx_buf);
288
289		vethprintf("write %d bytes...\n", m0->m_pkthdr.len);
290		len = thunk_write(sc->sc_tapfd, sc->sc_tx_buf,
291		    m0->m_pkthdr.len);
292		vethprintf("write returned %d\n", len);
293		if (len > 0)
294			++ifp->if_opackets;
295		else
296			++ifp->if_oerrors;
297		m_freem(m0);
298	}
299}
300
301static void
302veth_stop(struct ifnet *ifp, int disable)
303{
304	vethprintf("%s: %s flags=%x\n", __func__, ifp->if_xname, ifp->if_flags);
305	ifp->if_timer = 0;
306	ifp->if_flags &= ~(IFF_RUNNING | IFF_OACTIVE);
307}
308
309static void
310veth_watchdog(struct ifnet *ifp)
311{
312	vethprintf("%s: %s flags=%x\n", __func__, ifp->if_xname, ifp->if_flags);
313	++ifp->if_oerrors;
314	veth_init(ifp);
315}
316
317static int
318veth_ioctl(struct ifnet *ifp, u_long cmd, void *data)
319{
320	struct veth_softc *sc = ifp->if_softc;
321	struct ifreq *ifr;
322	int s, error;
323
324	vethprintf("%s: %s flags=%x\n", __func__, ifp->if_xname, ifp->if_flags);
325
326	s = splnet();
327
328	switch (cmd) {
329	case SIOCSIFMEDIA:
330	case SIOCGIFMEDIA:
331		ifr = data;
332		error = ifmedia_ioctl(ifp, ifr, &sc->sc_ifmedia, cmd);
333		break;
334	case SIOCADDMULTI:
335	case SIOCDELMULTI:
336		if ((error = ether_ioctl(ifp, cmd, data)) == ENETRESET) {
337			if (ifp->if_flags & IFF_RUNNING) {
338				veth_init(ifp);
339			}
340			error = 0;
341		}
342		break;
343	default:
344		error = ether_ioctl(ifp, cmd, data);
345		break;
346	}
347
348	splx(s);
349	return error;
350}
351
352static int
353veth_ifmedia_change(struct ifnet *ifp)
354{
355	vethprintf("%s: %s flags=%x\n", __func__, ifp->if_xname, ifp->if_flags);
356	return 0;
357}
358
359static void
360veth_ifmedia_status(struct ifnet *ifp, struct ifmediareq *req)
361{
362	vethprintf("%s: %s flags=%x\n", __func__, ifp->if_xname, ifp->if_flags);
363	req->ifm_status |= IFM_ACTIVE | IFM_AVALID;
364	req->ifm_active = IFM_100_TX | IFM_FDX | IFM_ETHER;
365}
366