xref: /freebsd/sys/dev/ntb/if_ntb/if_ntb.c (revision b0d29bc47dba79f6f38e67eabadfb4b32ffd9390)
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/cdefs.h>
41 __FBSDID("$FreeBSD$");
42 
43 #include <sys/param.h>
44 #include <sys/kernel.h>
45 #include <sys/systm.h>
46 #include <sys/buf_ring.h>
47 #include <sys/bus.h>
48 #include <sys/ktr.h>
49 #include <sys/limits.h>
50 #include <sys/module.h>
51 #include <sys/socket.h>
52 #include <sys/sockio.h>
53 #include <sys/sysctl.h>
54 #include <sys/taskqueue.h>
55 
56 #include <net/if.h>
57 #include <net/if_media.h>
58 #include <net/if_types.h>
59 #include <net/if_media.h>
60 #include <net/if_var.h>
61 #include <net/bpf.h>
62 #include <net/ethernet.h>
63 
64 #include <machine/bus.h>
65 
66 #include "../ntb_transport.h"
67 
68 #define KTR_NTB KTR_SPARE3
69 #define NTB_MEDIATYPE		 (IFM_ETHER | IFM_AUTO | IFM_FDX)
70 
71 #define	NTB_CSUM_FEATURES	(CSUM_IP | CSUM_TCP | CSUM_UDP | CSUM_SCTP)
72 #define	NTB_CSUM_FEATURES6	(CSUM_TCP_IPV6 | CSUM_UDP_IPV6 | CSUM_SCTP_IPV6)
73 #define	NTB_CSUM_SET		(CSUM_DATA_VALID | CSUM_DATA_VALID_IPV6 | \
74 				    CSUM_PSEUDO_HDR | \
75 				    CSUM_IP_CHECKED | CSUM_IP_VALID | \
76 				    CSUM_SCTP_VALID)
77 
78 static SYSCTL_NODE(_hw, OID_AUTO, if_ntb, CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
79     "if_ntb");
80 
81 static unsigned g_if_ntb_num_queues = UINT_MAX;
82 SYSCTL_UINT(_hw_if_ntb, OID_AUTO, num_queues, CTLFLAG_RWTUN,
83     &g_if_ntb_num_queues, 0, "Number of queues per interface");
84 
85 struct ntb_net_queue {
86 	struct ntb_net_ctx	*sc;
87 	if_t			 ifp;
88 	struct ntb_transport_qp *qp;
89 	struct buf_ring		*br;
90 	struct task		 tx_task;
91 	struct taskqueue	*tx_tq;
92 	struct mtx		 tx_lock;
93 	struct callout		 queue_full;
94 };
95 
96 struct ntb_net_ctx {
97 	if_t			 ifp;
98 	struct ifmedia		 media;
99 	u_char			 eaddr[ETHER_ADDR_LEN];
100 	int			 num_queues;
101 	struct ntb_net_queue	*queues;
102 	int			 mtu;
103 };
104 
105 static int ntb_net_probe(device_t dev);
106 static int ntb_net_attach(device_t dev);
107 static int ntb_net_detach(device_t dev);
108 static void ntb_net_init(void *arg);
109 static int ntb_ifmedia_upd(struct ifnet *);
110 static void ntb_ifmedia_sts(struct ifnet *, struct ifmediareq *);
111 static int ntb_ioctl(if_t ifp, u_long command, caddr_t data);
112 static int ntb_transmit(if_t ifp, struct mbuf *m);
113 static void ntb_net_tx_handler(struct ntb_transport_qp *qp, void *qp_data,
114     void *data, int len);
115 static void ntb_net_rx_handler(struct ntb_transport_qp *qp, void *qp_data,
116     void *data, int len);
117 static void ntb_net_event_handler(void *data, enum ntb_link_event status);
118 static void ntb_handle_tx(void *arg, int pending);
119 static void ntb_qp_full(void *arg);
120 static void ntb_qflush(if_t ifp);
121 static void create_random_local_eui48(u_char *eaddr);
122 
123 static int
124 ntb_net_probe(device_t dev)
125 {
126 
127 	device_set_desc(dev, "NTB Network Interface");
128 	return (0);
129 }
130 
131 static int
132 ntb_net_attach(device_t dev)
133 {
134 	struct ntb_net_ctx *sc = device_get_softc(dev);
135 	struct ntb_net_queue *q;
136 	if_t ifp;
137 	struct ntb_queue_handlers handlers = { ntb_net_rx_handler,
138 	    ntb_net_tx_handler, ntb_net_event_handler };
139 	int i;
140 
141 	ifp = sc->ifp = if_gethandle(IFT_ETHER);
142 	if (ifp == NULL) {
143 		printf("ntb: Cannot allocate ifnet structure\n");
144 		return (ENOMEM);
145 	}
146 	if_initname(ifp, device_get_name(dev), device_get_unit(dev));
147 	if_setdev(ifp, dev);
148 
149 	sc->num_queues = min(g_if_ntb_num_queues,
150 	    ntb_transport_queue_count(dev));
151 	sc->queues = malloc(sc->num_queues * sizeof(struct ntb_net_queue),
152 	    M_DEVBUF, M_WAITOK | M_ZERO);
153 	sc->mtu = INT_MAX;
154 	for (i = 0; i < sc->num_queues; i++) {
155 		q = &sc->queues[i];
156 		q->sc = sc;
157 		q->ifp = ifp;
158 		q->qp = ntb_transport_create_queue(dev, i, &handlers, q);
159 		if (q->qp == NULL)
160 			break;
161 		sc->mtu = imin(sc->mtu, ntb_transport_max_size(q->qp));
162 		mtx_init(&q->tx_lock, "ntb tx", NULL, MTX_DEF);
163 		q->br = buf_ring_alloc(4096, M_DEVBUF, M_WAITOK, &q->tx_lock);
164 		TASK_INIT(&q->tx_task, 0, ntb_handle_tx, q);
165 		q->tx_tq = taskqueue_create_fast("ntb_txq", M_NOWAIT,
166 		    taskqueue_thread_enqueue, &q->tx_tq);
167 		taskqueue_start_threads(&q->tx_tq, 1, PI_NET, "%s txq%d",
168 		    device_get_nameunit(dev), i);
169 		callout_init(&q->queue_full, 1);
170 	}
171 	sc->num_queues = i;
172 	device_printf(dev, "%d queue(s)\n", sc->num_queues);
173 
174 	if_setinitfn(ifp, ntb_net_init);
175 	if_setsoftc(ifp, sc);
176 	if_setflags(ifp, IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST);
177 	if_setioctlfn(ifp, ntb_ioctl);
178 	if_settransmitfn(ifp, ntb_transmit);
179 	if_setqflushfn(ifp, ntb_qflush);
180 	create_random_local_eui48(sc->eaddr);
181 	ether_ifattach(ifp, sc->eaddr);
182 	if_setcapabilities(ifp, IFCAP_HWCSUM | IFCAP_HWCSUM_IPV6 |
183 	    IFCAP_JUMBO_MTU | IFCAP_LINKSTATE);
184 	if_setcapenable(ifp, IFCAP_JUMBO_MTU | IFCAP_LINKSTATE);
185 	if_setmtu(ifp, sc->mtu - ETHER_HDR_LEN);
186 
187 	ifmedia_init(&sc->media, IFM_IMASK, ntb_ifmedia_upd,
188 	    ntb_ifmedia_sts);
189 	ifmedia_add(&sc->media, NTB_MEDIATYPE, 0, NULL);
190 	ifmedia_set(&sc->media, NTB_MEDIATYPE);
191 
192 	for (i = 0; i < sc->num_queues; i++)
193 		ntb_transport_link_up(sc->queues[i].qp);
194 	return (0);
195 }
196 
197 static int
198 ntb_net_detach(device_t dev)
199 {
200 	struct ntb_net_ctx *sc = device_get_softc(dev);
201 	struct ntb_net_queue *q;
202 	int i;
203 
204 	for (i = 0; i < sc->num_queues; i++)
205 		ntb_transport_link_down(sc->queues[i].qp);
206 	ether_ifdetach(sc->ifp);
207 	if_free(sc->ifp);
208 	ifmedia_removeall(&sc->media);
209 	for (i = 0; i < sc->num_queues; i++) {
210 		q = &sc->queues[i];
211 		ntb_transport_free_queue(q->qp);
212 		buf_ring_free(q->br, M_DEVBUF);
213 		callout_drain(&q->queue_full);
214 		taskqueue_drain_all(q->tx_tq);
215 		mtx_destroy(&q->tx_lock);
216 	}
217 	free(sc->queues, M_DEVBUF);
218 	return (0);
219 }
220 
221 /* Network device interface */
222 
223 static void
224 ntb_net_init(void *arg)
225 {
226 	struct ntb_net_ctx *sc = arg;
227 	if_t ifp = sc->ifp;
228 
229 	if_setdrvflagbits(ifp, IFF_DRV_RUNNING, IFF_DRV_OACTIVE);
230 	if_setbaudrate(ifp, ntb_transport_link_speed(sc->queues[0].qp));
231 	if_link_state_change(ifp, ntb_transport_link_query(sc->queues[0].qp) ?
232 	    LINK_STATE_UP : LINK_STATE_DOWN);
233 }
234 
235 static int
236 ntb_ioctl(if_t ifp, u_long command, caddr_t data)
237 {
238 	struct ntb_net_ctx *sc = if_getsoftc(ifp);
239 	struct ifreq *ifr = (struct ifreq *)data;
240 	int error = 0;
241 
242 	switch (command) {
243 	case SIOCSIFFLAGS:
244 	case SIOCADDMULTI:
245 	case SIOCDELMULTI:
246 		break;
247 
248 	case SIOCSIFMTU:
249 	    {
250 		if (ifr->ifr_mtu > sc->mtu - ETHER_HDR_LEN) {
251 			error = EINVAL;
252 			break;
253 		}
254 
255 		if_setmtu(ifp, ifr->ifr_mtu);
256 		break;
257 	    }
258 
259 	case SIOCSIFMEDIA:
260 	case SIOCGIFMEDIA:
261 		error = ifmedia_ioctl(ifp, ifr, &sc->media, command);
262 		break;
263 
264 	case SIOCSIFCAP:
265 		if (ifr->ifr_reqcap & IFCAP_RXCSUM)
266 			if_setcapenablebit(ifp, IFCAP_RXCSUM, 0);
267 		else
268 			if_setcapenablebit(ifp, 0, IFCAP_RXCSUM);
269 		if (ifr->ifr_reqcap & IFCAP_TXCSUM) {
270 			if_setcapenablebit(ifp, IFCAP_TXCSUM, 0);
271 			if_sethwassistbits(ifp, NTB_CSUM_FEATURES, 0);
272 		} else {
273 			if_setcapenablebit(ifp, 0, IFCAP_TXCSUM);
274 			if_sethwassistbits(ifp, 0, NTB_CSUM_FEATURES);
275 		}
276 		if (ifr->ifr_reqcap & IFCAP_RXCSUM_IPV6)
277 			if_setcapenablebit(ifp, IFCAP_RXCSUM_IPV6, 0);
278 		else
279 			if_setcapenablebit(ifp, 0, IFCAP_RXCSUM_IPV6);
280 		if (ifr->ifr_reqcap & IFCAP_TXCSUM_IPV6) {
281 			if_setcapenablebit(ifp, IFCAP_TXCSUM_IPV6, 0);
282 			if_sethwassistbits(ifp, NTB_CSUM_FEATURES6, 0);
283 		} else {
284 			if_setcapenablebit(ifp, 0, IFCAP_TXCSUM_IPV6);
285 			if_sethwassistbits(ifp, 0, NTB_CSUM_FEATURES6);
286 		}
287 		break;
288 
289 	default:
290 		error = ether_ioctl(ifp, command, data);
291 		break;
292 	}
293 
294 	return (error);
295 }
296 
297 static int
298 ntb_ifmedia_upd(struct ifnet *ifp)
299 {
300 	struct ntb_net_ctx *sc = if_getsoftc(ifp);
301 	struct ifmedia *ifm = &sc->media;
302 
303 	if (IFM_TYPE(ifm->ifm_media) != IFM_ETHER)
304 		return (EINVAL);
305 
306 	return (0);
307 }
308 
309 static void
310 ntb_ifmedia_sts(struct ifnet *ifp, struct ifmediareq *ifmr)
311 {
312 	struct ntb_net_ctx *sc = if_getsoftc(ifp);
313 
314 	ifmr->ifm_status = IFM_AVALID;
315 	ifmr->ifm_active = NTB_MEDIATYPE;
316 	if (ntb_transport_link_query(sc->queues[0].qp))
317 		ifmr->ifm_status |= IFM_ACTIVE;
318 }
319 
320 static void
321 ntb_transmit_locked(struct ntb_net_queue *q)
322 {
323 	if_t ifp = q->ifp;
324 	struct mbuf *m;
325 	int rc, len;
326 	short mflags;
327 
328 	CTR0(KTR_NTB, "TX: ntb_transmit_locked");
329 	while ((m = drbr_peek(ifp, q->br)) != NULL) {
330 		CTR1(KTR_NTB, "TX: start mbuf %p", m);
331 		if_etherbpfmtap(ifp, m);
332 		len = m->m_pkthdr.len;
333 		mflags = m->m_flags;
334 		rc = ntb_transport_tx_enqueue(q->qp, m, m, len);
335 		if (rc != 0) {
336 			CTR2(KTR_NTB, "TX: could not tx mbuf %p: %d", m, rc);
337 			if (rc == EAGAIN) {
338 				drbr_putback(ifp, q->br, m);
339 				callout_reset_sbt(&q->queue_full,
340 				    SBT_1MS / 4, SBT_1MS / 4,
341 				    ntb_qp_full, q, 0);
342 			} else {
343 				m_freem(m);
344 				drbr_advance(ifp, q->br);
345 				if_inc_counter(ifp, IFCOUNTER_OERRORS, 1);
346 			}
347 			break;
348 		}
349 		drbr_advance(ifp, q->br);
350 		if_inc_counter(ifp, IFCOUNTER_OPACKETS, 1);
351 		if_inc_counter(ifp, IFCOUNTER_OBYTES, len);
352 		if (mflags & M_MCAST)
353 			if_inc_counter(ifp, IFCOUNTER_OMCASTS, 1);
354 	}
355 }
356 
357 static int
358 ntb_transmit(if_t ifp, struct mbuf *m)
359 {
360 	struct ntb_net_ctx *sc = if_getsoftc(ifp);
361 	struct ntb_net_queue *q;
362 	int error, i;
363 
364 	CTR0(KTR_NTB, "TX: ntb_transmit");
365 	if (M_HASHTYPE_GET(m) != M_HASHTYPE_NONE)
366 		i = m->m_pkthdr.flowid % sc->num_queues;
367 	else
368 		i = curcpu % sc->num_queues;
369 	q = &sc->queues[i];
370 
371 	error = drbr_enqueue(ifp, q->br, m);
372 	if (error)
373 		return (error);
374 
375 	if (mtx_trylock(&q->tx_lock)) {
376 		ntb_transmit_locked(q);
377 		mtx_unlock(&q->tx_lock);
378 	} else
379 		taskqueue_enqueue(q->tx_tq, &q->tx_task);
380 	return (0);
381 }
382 
383 static void
384 ntb_handle_tx(void *arg, int pending)
385 {
386 	struct ntb_net_queue *q = arg;
387 
388 	mtx_lock(&q->tx_lock);
389 	ntb_transmit_locked(q);
390 	mtx_unlock(&q->tx_lock);
391 }
392 
393 static void
394 ntb_qp_full(void *arg)
395 {
396 	struct ntb_net_queue *q = arg;
397 
398 	CTR0(KTR_NTB, "TX: qp_full callout");
399 	if (ntb_transport_tx_free_entry(q->qp) > 0)
400 		taskqueue_enqueue(q->tx_tq, &q->tx_task);
401 	else
402 		callout_schedule_sbt(&q->queue_full,
403 		    SBT_1MS / 4, SBT_1MS / 4, 0);
404 }
405 
406 static void
407 ntb_qflush(if_t ifp)
408 {
409 	struct ntb_net_ctx *sc = if_getsoftc(ifp);
410 	struct ntb_net_queue *q;
411 	struct mbuf *m;
412 	int i;
413 
414 	for (i = 0; i < sc->num_queues; i++) {
415 		q = &sc->queues[i];
416 		mtx_lock(&q->tx_lock);
417 		while ((m = buf_ring_dequeue_sc(q->br)) != NULL)
418 			m_freem(m);
419 		mtx_unlock(&q->tx_lock);
420 	}
421 	if_qflush(ifp);
422 }
423 
424 /* Network Device Callbacks */
425 static void
426 ntb_net_tx_handler(struct ntb_transport_qp *qp, void *qp_data, void *data,
427     int len)
428 {
429 
430 	m_freem(data);
431 	CTR1(KTR_NTB, "TX: tx_handler freeing mbuf %p", data);
432 }
433 
434 static void
435 ntb_net_rx_handler(struct ntb_transport_qp *qp, void *qp_data, void *data,
436     int len)
437 {
438 	struct ntb_net_queue *q = qp_data;
439 	struct ntb_net_ctx *sc = q->sc;
440 	struct mbuf *m = data;
441 	if_t ifp = q->ifp;
442 	uint16_t proto;
443 
444 	CTR1(KTR_NTB, "RX: rx handler (%d)", len);
445 	if (len < 0) {
446 		if_inc_counter(ifp, IFCOUNTER_IERRORS, 1);
447 		return;
448 	}
449 
450 	m->m_pkthdr.rcvif = ifp;
451 	if (sc->num_queues > 1) {
452 		m->m_pkthdr.flowid = q - sc->queues;
453 		M_HASHTYPE_SET(m, M_HASHTYPE_OPAQUE);
454 	}
455 	if (if_getcapenable(ifp) & (IFCAP_RXCSUM | IFCAP_RXCSUM_IPV6)) {
456 		m_copydata(m, 12, 2, (void *)&proto);
457 		switch (ntohs(proto)) {
458 		case ETHERTYPE_IP:
459 			if (if_getcapenable(ifp) & IFCAP_RXCSUM) {
460 				m->m_pkthdr.csum_data = 0xffff;
461 				m->m_pkthdr.csum_flags = NTB_CSUM_SET;
462 			}
463 			break;
464 		case ETHERTYPE_IPV6:
465 			if (if_getcapenable(ifp) & IFCAP_RXCSUM_IPV6) {
466 				m->m_pkthdr.csum_data = 0xffff;
467 				m->m_pkthdr.csum_flags = NTB_CSUM_SET;
468 			}
469 			break;
470 		}
471 	}
472 	if_inc_counter(ifp, IFCOUNTER_IPACKETS, 1);
473 	if_input(ifp, m);
474 }
475 
476 static void
477 ntb_net_event_handler(void *data, enum ntb_link_event status)
478 {
479 	struct ntb_net_queue *q = data;
480 
481 	if_setbaudrate(q->ifp, ntb_transport_link_speed(q->qp));
482 	if_link_state_change(q->ifp, (status == NTB_LINK_UP) ? LINK_STATE_UP :
483 	    LINK_STATE_DOWN);
484 }
485 
486 /* Helper functions */
487 /* TODO: This too should really be part of the kernel */
488 #define EUI48_MULTICAST			1 << 0
489 #define EUI48_LOCALLY_ADMINISTERED	1 << 1
490 static void
491 create_random_local_eui48(u_char *eaddr)
492 {
493 	static uint8_t counter = 0;
494 
495 	eaddr[0] = EUI48_LOCALLY_ADMINISTERED;
496 	arc4rand(&eaddr[1], 4, 0);
497 	eaddr[5] = counter++;
498 }
499 
500 static device_method_t ntb_net_methods[] = {
501 	/* Device interface */
502 	DEVMETHOD(device_probe,     ntb_net_probe),
503 	DEVMETHOD(device_attach,    ntb_net_attach),
504 	DEVMETHOD(device_detach,    ntb_net_detach),
505 	DEVMETHOD_END
506 };
507 
508 devclass_t ntb_net_devclass;
509 static DEFINE_CLASS_0(ntb, ntb_net_driver, ntb_net_methods,
510     sizeof(struct ntb_net_ctx));
511 DRIVER_MODULE(if_ntb, ntb_transport, ntb_net_driver, ntb_net_devclass,
512     NULL, NULL);
513 MODULE_DEPEND(if_ntb, ntb_transport, 1, 1, 1);
514 MODULE_VERSION(if_ntb, 1);
515