xref: /freebsd/sys/dev/ntb/if_ntb/if_ntb.c (revision 96190b4fef3b4a0cc3ca0606b0c4e3e69a5e6717)
1 /*-
2  * Copyright (c) 2016 Alexander Motin <mav@FreeBSD.org>
3  * Copyright (C) 2013 Intel Corporation
4  * Copyright (C) 2015 EMC Corporation
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 AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 
29 /*
30  * The Non-Transparent Bridge (NTB) is a device that allows you to connect
31  * two or more systems using a PCI-e links, providing remote memory access.
32  *
33  * This module contains a driver for simulated Ethernet device, using
34  * underlying NTB Transport device.
35  *
36  * NOTE: Much of the code in this module is shared with Linux. Any patches may
37  * be picked up and redistributed in Linux with a dual GPL/BSD license.
38  */
39 
40 #include <sys/param.h>
41 #include <sys/kernel.h>
42 #include <sys/systm.h>
43 #include <sys/buf_ring.h>
44 #include <sys/bus.h>
45 #include <sys/ktr.h>
46 #include <sys/limits.h>
47 #include <sys/module.h>
48 #include <sys/socket.h>
49 #include <sys/sockio.h>
50 #include <sys/sysctl.h>
51 #include <sys/taskqueue.h>
52 
53 #include <net/if.h>
54 #include <net/if_media.h>
55 #include <net/if_types.h>
56 #include <net/if_media.h>
57 #include <net/if_var.h>
58 #include <net/bpf.h>
59 #include <net/ethernet.h>
60 
61 #include <machine/bus.h>
62 
63 #include "../ntb_transport.h"
64 
65 #define KTR_NTB KTR_SPARE3
66 #define NTB_MEDIATYPE		 (IFM_ETHER | IFM_AUTO | IFM_FDX)
67 
68 #define	NTB_CSUM_FEATURES	(CSUM_IP | CSUM_TCP | CSUM_UDP | CSUM_SCTP)
69 #define	NTB_CSUM_FEATURES6	(CSUM_TCP_IPV6 | CSUM_UDP_IPV6 | CSUM_SCTP_IPV6)
70 #define	NTB_CSUM_SET		(CSUM_DATA_VALID | CSUM_DATA_VALID_IPV6 | \
71 				    CSUM_PSEUDO_HDR | \
72 				    CSUM_IP_CHECKED | CSUM_IP_VALID | \
73 				    CSUM_SCTP_VALID)
74 
75 static SYSCTL_NODE(_hw, OID_AUTO, if_ntb, CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
76     "if_ntb");
77 
78 static unsigned g_if_ntb_num_queues = UINT_MAX;
79 SYSCTL_UINT(_hw_if_ntb, OID_AUTO, num_queues, CTLFLAG_RWTUN,
80     &g_if_ntb_num_queues, 0, "Number of queues per interface");
81 
82 struct ntb_net_queue {
83 	struct ntb_net_ctx	*sc;
84 	if_t			 ifp;
85 	struct ntb_transport_qp *qp;
86 	struct buf_ring		*br;
87 	struct task		 tx_task;
88 	struct taskqueue	*tx_tq;
89 	struct mtx		 tx_lock;
90 	struct callout		 queue_full;
91 };
92 
93 struct ntb_net_ctx {
94 	if_t			 ifp;
95 	struct ifmedia		 media;
96 	u_char			 eaddr[ETHER_ADDR_LEN];
97 	int			 num_queues;
98 	struct ntb_net_queue	*queues;
99 	int			 mtu;
100 };
101 
102 static int ntb_net_probe(device_t dev);
103 static int ntb_net_attach(device_t dev);
104 static int ntb_net_detach(device_t dev);
105 static void ntb_net_init(void *arg);
106 static int ntb_ifmedia_upd(struct ifnet *);
107 static void ntb_ifmedia_sts(struct ifnet *, struct ifmediareq *);
108 static int ntb_ioctl(if_t ifp, u_long command, caddr_t data);
109 static int ntb_transmit(if_t ifp, struct mbuf *m);
110 static void ntb_net_tx_handler(struct ntb_transport_qp *qp, void *qp_data,
111     void *data, int len);
112 static void ntb_net_rx_handler(struct ntb_transport_qp *qp, void *qp_data,
113     void *data, int len);
114 static void ntb_net_event_handler(void *data, enum ntb_link_event status);
115 static void ntb_handle_tx(void *arg, int pending);
116 static void ntb_qp_full(void *arg);
117 static void ntb_qflush(if_t ifp);
118 static void create_random_local_eui48(u_char *eaddr);
119 
120 static int
121 ntb_net_probe(device_t dev)
122 {
123 
124 	device_set_desc(dev, "NTB Network Interface");
125 	return (0);
126 }
127 
128 static int
129 ntb_net_attach(device_t dev)
130 {
131 	struct ntb_net_ctx *sc = device_get_softc(dev);
132 	struct ntb_net_queue *q;
133 	if_t ifp;
134 	struct ntb_queue_handlers handlers = { ntb_net_rx_handler,
135 	    ntb_net_tx_handler, ntb_net_event_handler };
136 	int i;
137 
138 	ifp = sc->ifp = if_gethandle(IFT_ETHER);
139 	if_initname(ifp, device_get_name(dev), device_get_unit(dev));
140 	if_setdev(ifp, dev);
141 
142 	sc->num_queues = min(g_if_ntb_num_queues,
143 	    ntb_transport_queue_count(dev));
144 	sc->queues = malloc(sc->num_queues * sizeof(struct ntb_net_queue),
145 	    M_DEVBUF, M_WAITOK | M_ZERO);
146 	sc->mtu = INT_MAX;
147 	for (i = 0; i < sc->num_queues; i++) {
148 		q = &sc->queues[i];
149 		q->sc = sc;
150 		q->ifp = ifp;
151 		q->qp = ntb_transport_create_queue(dev, i, &handlers, q);
152 		if (q->qp == NULL)
153 			break;
154 		sc->mtu = imin(sc->mtu, ntb_transport_max_size(q->qp));
155 		mtx_init(&q->tx_lock, "ntb tx", NULL, MTX_DEF);
156 		q->br = buf_ring_alloc(4096, M_DEVBUF, M_WAITOK, &q->tx_lock);
157 		TASK_INIT(&q->tx_task, 0, ntb_handle_tx, q);
158 		q->tx_tq = taskqueue_create_fast("ntb_txq", M_NOWAIT,
159 		    taskqueue_thread_enqueue, &q->tx_tq);
160 		taskqueue_start_threads(&q->tx_tq, 1, PI_NET, "%s txq%d",
161 		    device_get_nameunit(dev), i);
162 		callout_init(&q->queue_full, 1);
163 	}
164 	sc->num_queues = i;
165 	device_printf(dev, "%d queue(s)\n", sc->num_queues);
166 
167 	if_setinitfn(ifp, ntb_net_init);
168 	if_setsoftc(ifp, sc);
169 	if_setflags(ifp, IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST);
170 	if_setioctlfn(ifp, ntb_ioctl);
171 	if_settransmitfn(ifp, ntb_transmit);
172 	if_setqflushfn(ifp, ntb_qflush);
173 	create_random_local_eui48(sc->eaddr);
174 	ether_ifattach(ifp, sc->eaddr);
175 	if_setcapabilities(ifp, IFCAP_HWCSUM | IFCAP_HWCSUM_IPV6 |
176 	    IFCAP_JUMBO_MTU | IFCAP_LINKSTATE);
177 	if_setcapenable(ifp, IFCAP_JUMBO_MTU | IFCAP_LINKSTATE);
178 	if_setmtu(ifp, sc->mtu - ETHER_HDR_LEN);
179 
180 	ifmedia_init(&sc->media, IFM_IMASK, ntb_ifmedia_upd,
181 	    ntb_ifmedia_sts);
182 	ifmedia_add(&sc->media, NTB_MEDIATYPE, 0, NULL);
183 	ifmedia_set(&sc->media, NTB_MEDIATYPE);
184 
185 	for (i = 0; i < sc->num_queues; i++)
186 		ntb_transport_link_up(sc->queues[i].qp);
187 	return (0);
188 }
189 
190 static int
191 ntb_net_detach(device_t dev)
192 {
193 	struct ntb_net_ctx *sc = device_get_softc(dev);
194 	struct ntb_net_queue *q;
195 	int i;
196 
197 	for (i = 0; i < sc->num_queues; i++)
198 		ntb_transport_link_down(sc->queues[i].qp);
199 	ether_ifdetach(sc->ifp);
200 	if_free(sc->ifp);
201 	ifmedia_removeall(&sc->media);
202 	for (i = 0; i < sc->num_queues; i++) {
203 		q = &sc->queues[i];
204 		ntb_transport_free_queue(q->qp);
205 		buf_ring_free(q->br, M_DEVBUF);
206 		callout_drain(&q->queue_full);
207 		taskqueue_drain_all(q->tx_tq);
208 		mtx_destroy(&q->tx_lock);
209 	}
210 	free(sc->queues, M_DEVBUF);
211 	return (0);
212 }
213 
214 /* Network device interface */
215 
216 static void
217 ntb_net_init(void *arg)
218 {
219 	struct ntb_net_ctx *sc = arg;
220 	if_t ifp = sc->ifp;
221 
222 	if_setdrvflagbits(ifp, IFF_DRV_RUNNING, IFF_DRV_OACTIVE);
223 	if_setbaudrate(ifp, ntb_transport_link_speed(sc->queues[0].qp));
224 	if_link_state_change(ifp, ntb_transport_link_query(sc->queues[0].qp) ?
225 	    LINK_STATE_UP : LINK_STATE_DOWN);
226 }
227 
228 static int
229 ntb_ioctl(if_t ifp, u_long command, caddr_t data)
230 {
231 	struct ntb_net_ctx *sc = if_getsoftc(ifp);
232 	struct ifreq *ifr = (struct ifreq *)data;
233 	int error = 0;
234 
235 	switch (command) {
236 	case SIOCSIFFLAGS:
237 	case SIOCADDMULTI:
238 	case SIOCDELMULTI:
239 		break;
240 
241 	case SIOCSIFMTU:
242 	    {
243 		if (ifr->ifr_mtu > sc->mtu - ETHER_HDR_LEN) {
244 			error = EINVAL;
245 			break;
246 		}
247 
248 		if_setmtu(ifp, ifr->ifr_mtu);
249 		break;
250 	    }
251 
252 	case SIOCSIFMEDIA:
253 	case SIOCGIFMEDIA:
254 		error = ifmedia_ioctl(ifp, ifr, &sc->media, command);
255 		break;
256 
257 	case SIOCSIFCAP:
258 		if (ifr->ifr_reqcap & IFCAP_RXCSUM)
259 			if_setcapenablebit(ifp, IFCAP_RXCSUM, 0);
260 		else
261 			if_setcapenablebit(ifp, 0, IFCAP_RXCSUM);
262 		if (ifr->ifr_reqcap & IFCAP_TXCSUM) {
263 			if_setcapenablebit(ifp, IFCAP_TXCSUM, 0);
264 			if_sethwassistbits(ifp, NTB_CSUM_FEATURES, 0);
265 		} else {
266 			if_setcapenablebit(ifp, 0, IFCAP_TXCSUM);
267 			if_sethwassistbits(ifp, 0, NTB_CSUM_FEATURES);
268 		}
269 		if (ifr->ifr_reqcap & IFCAP_RXCSUM_IPV6)
270 			if_setcapenablebit(ifp, IFCAP_RXCSUM_IPV6, 0);
271 		else
272 			if_setcapenablebit(ifp, 0, IFCAP_RXCSUM_IPV6);
273 		if (ifr->ifr_reqcap & IFCAP_TXCSUM_IPV6) {
274 			if_setcapenablebit(ifp, IFCAP_TXCSUM_IPV6, 0);
275 			if_sethwassistbits(ifp, NTB_CSUM_FEATURES6, 0);
276 		} else {
277 			if_setcapenablebit(ifp, 0, IFCAP_TXCSUM_IPV6);
278 			if_sethwassistbits(ifp, 0, NTB_CSUM_FEATURES6);
279 		}
280 		break;
281 
282 	default:
283 		error = ether_ioctl(ifp, command, data);
284 		break;
285 	}
286 
287 	return (error);
288 }
289 
290 static int
291 ntb_ifmedia_upd(struct ifnet *ifp)
292 {
293 	struct ntb_net_ctx *sc = if_getsoftc(ifp);
294 	struct ifmedia *ifm = &sc->media;
295 
296 	if (IFM_TYPE(ifm->ifm_media) != IFM_ETHER)
297 		return (EINVAL);
298 
299 	return (0);
300 }
301 
302 static void
303 ntb_ifmedia_sts(struct ifnet *ifp, struct ifmediareq *ifmr)
304 {
305 	struct ntb_net_ctx *sc = if_getsoftc(ifp);
306 
307 	ifmr->ifm_status = IFM_AVALID;
308 	ifmr->ifm_active = NTB_MEDIATYPE;
309 	if (ntb_transport_link_query(sc->queues[0].qp))
310 		ifmr->ifm_status |= IFM_ACTIVE;
311 }
312 
313 static void
314 ntb_transmit_locked(struct ntb_net_queue *q)
315 {
316 	if_t ifp = q->ifp;
317 	struct mbuf *m;
318 	int rc, len;
319 	short mflags;
320 
321 	CTR0(KTR_NTB, "TX: ntb_transmit_locked");
322 	while ((m = drbr_peek(ifp, q->br)) != NULL) {
323 		CTR1(KTR_NTB, "TX: start mbuf %p", m);
324 		ether_bpf_mtap_if(ifp, m);
325 		len = m->m_pkthdr.len;
326 		mflags = m->m_flags;
327 		rc = ntb_transport_tx_enqueue(q->qp, m, m, len);
328 		if (rc != 0) {
329 			CTR2(KTR_NTB, "TX: could not tx mbuf %p: %d", m, rc);
330 			if (rc == EAGAIN) {
331 				drbr_putback(ifp, q->br, m);
332 				callout_reset_sbt(&q->queue_full,
333 				    SBT_1MS / 4, SBT_1MS / 4,
334 				    ntb_qp_full, q, 0);
335 			} else {
336 				m_freem(m);
337 				drbr_advance(ifp, q->br);
338 				if_inc_counter(ifp, IFCOUNTER_OERRORS, 1);
339 			}
340 			break;
341 		}
342 		drbr_advance(ifp, q->br);
343 		if_inc_counter(ifp, IFCOUNTER_OPACKETS, 1);
344 		if_inc_counter(ifp, IFCOUNTER_OBYTES, len);
345 		if (mflags & M_MCAST)
346 			if_inc_counter(ifp, IFCOUNTER_OMCASTS, 1);
347 	}
348 }
349 
350 static int
351 ntb_transmit(if_t ifp, struct mbuf *m)
352 {
353 	struct ntb_net_ctx *sc = if_getsoftc(ifp);
354 	struct ntb_net_queue *q;
355 	int error, i;
356 
357 	CTR0(KTR_NTB, "TX: ntb_transmit");
358 	if (M_HASHTYPE_GET(m) != M_HASHTYPE_NONE)
359 		i = m->m_pkthdr.flowid % sc->num_queues;
360 	else
361 		i = curcpu % sc->num_queues;
362 	q = &sc->queues[i];
363 
364 	error = drbr_enqueue(ifp, q->br, m);
365 	if (error)
366 		return (error);
367 
368 	if (mtx_trylock(&q->tx_lock)) {
369 		ntb_transmit_locked(q);
370 		mtx_unlock(&q->tx_lock);
371 	} else
372 		taskqueue_enqueue(q->tx_tq, &q->tx_task);
373 	return (0);
374 }
375 
376 static void
377 ntb_handle_tx(void *arg, int pending)
378 {
379 	struct ntb_net_queue *q = arg;
380 
381 	mtx_lock(&q->tx_lock);
382 	ntb_transmit_locked(q);
383 	mtx_unlock(&q->tx_lock);
384 }
385 
386 static void
387 ntb_qp_full(void *arg)
388 {
389 	struct ntb_net_queue *q = arg;
390 
391 	CTR0(KTR_NTB, "TX: qp_full callout");
392 	if (ntb_transport_tx_free_entry(q->qp) > 0)
393 		taskqueue_enqueue(q->tx_tq, &q->tx_task);
394 	else
395 		callout_schedule_sbt(&q->queue_full,
396 		    SBT_1MS / 4, SBT_1MS / 4, 0);
397 }
398 
399 static void
400 ntb_qflush(if_t ifp)
401 {
402 	struct ntb_net_ctx *sc = if_getsoftc(ifp);
403 	struct ntb_net_queue *q;
404 	struct mbuf *m;
405 	int i;
406 
407 	for (i = 0; i < sc->num_queues; i++) {
408 		q = &sc->queues[i];
409 		mtx_lock(&q->tx_lock);
410 		while ((m = buf_ring_dequeue_sc(q->br)) != NULL)
411 			m_freem(m);
412 		mtx_unlock(&q->tx_lock);
413 	}
414 	if_qflush(ifp);
415 }
416 
417 /* Network Device Callbacks */
418 static void
419 ntb_net_tx_handler(struct ntb_transport_qp *qp, void *qp_data, void *data,
420     int len)
421 {
422 
423 	m_freem(data);
424 	CTR1(KTR_NTB, "TX: tx_handler freeing mbuf %p", data);
425 }
426 
427 static void
428 ntb_net_rx_handler(struct ntb_transport_qp *qp, void *qp_data, void *data,
429     int len)
430 {
431 	struct ntb_net_queue *q = qp_data;
432 	struct ntb_net_ctx *sc = q->sc;
433 	struct mbuf *m = data;
434 	if_t ifp = q->ifp;
435 	uint16_t proto;
436 
437 	CTR1(KTR_NTB, "RX: rx handler (%d)", len);
438 	if (len < 0) {
439 		if_inc_counter(ifp, IFCOUNTER_IERRORS, 1);
440 		return;
441 	}
442 
443 	m->m_pkthdr.rcvif = ifp;
444 	if (sc->num_queues > 1) {
445 		m->m_pkthdr.flowid = q - sc->queues;
446 		M_HASHTYPE_SET(m, M_HASHTYPE_OPAQUE);
447 	}
448 	if (if_getcapenable(ifp) & (IFCAP_RXCSUM | IFCAP_RXCSUM_IPV6)) {
449 		m_copydata(m, 12, 2, (void *)&proto);
450 		switch (ntohs(proto)) {
451 		case ETHERTYPE_IP:
452 			if (if_getcapenable(ifp) & IFCAP_RXCSUM) {
453 				m->m_pkthdr.csum_data = 0xffff;
454 				m->m_pkthdr.csum_flags = NTB_CSUM_SET;
455 			}
456 			break;
457 		case ETHERTYPE_IPV6:
458 			if (if_getcapenable(ifp) & IFCAP_RXCSUM_IPV6) {
459 				m->m_pkthdr.csum_data = 0xffff;
460 				m->m_pkthdr.csum_flags = NTB_CSUM_SET;
461 			}
462 			break;
463 		}
464 	}
465 	if_inc_counter(ifp, IFCOUNTER_IPACKETS, 1);
466 	if_input(ifp, m);
467 }
468 
469 static void
470 ntb_net_event_handler(void *data, enum ntb_link_event status)
471 {
472 	struct ntb_net_queue *q = data;
473 
474 	if_setbaudrate(q->ifp, ntb_transport_link_speed(q->qp));
475 	if_link_state_change(q->ifp, (status == NTB_LINK_UP) ? LINK_STATE_UP :
476 	    LINK_STATE_DOWN);
477 }
478 
479 /* Helper functions */
480 /* TODO: This too should really be part of the kernel */
481 #define EUI48_MULTICAST			1 << 0
482 #define EUI48_LOCALLY_ADMINISTERED	1 << 1
483 static void
484 create_random_local_eui48(u_char *eaddr)
485 {
486 	static uint8_t counter = 0;
487 
488 	eaddr[0] = EUI48_LOCALLY_ADMINISTERED;
489 	arc4rand(&eaddr[1], 4, 0);
490 	eaddr[5] = counter++;
491 }
492 
493 static device_method_t ntb_net_methods[] = {
494 	/* Device interface */
495 	DEVMETHOD(device_probe,     ntb_net_probe),
496 	DEVMETHOD(device_attach,    ntb_net_attach),
497 	DEVMETHOD(device_detach,    ntb_net_detach),
498 	DEVMETHOD_END
499 };
500 
501 static DEFINE_CLASS_0(ntb, ntb_net_driver, ntb_net_methods,
502     sizeof(struct ntb_net_ctx));
503 DRIVER_MODULE(if_ntb, ntb_transport, ntb_net_driver, NULL, NULL);
504 MODULE_DEPEND(if_ntb, ntb_transport, 1, 1, 1);
505 MODULE_VERSION(if_ntb, 1);
506