xref: /freebsd/sys/dev/ntb/if_ntb/if_ntb.c (revision b0f79e328e18f454a54011ab1bb09e4910e73840)
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, 0, "if_ntb");
79 
80 static unsigned g_if_ntb_num_queues = UINT_MAX;
81 SYSCTL_UINT(_hw_if_ntb, OID_AUTO, num_queues, CTLFLAG_RWTUN,
82     &g_if_ntb_num_queues, 0, "Number of queues per interface");
83 
84 struct ntb_net_queue {
85 	struct ntb_net_ctx	*sc;
86 	if_t			 ifp;
87 	struct ntb_transport_qp *qp;
88 	struct buf_ring		*br;
89 	struct task		 tx_task;
90 	struct taskqueue	*tx_tq;
91 	struct mtx		 tx_lock;
92 	struct callout		 queue_full;
93 };
94 
95 struct ntb_net_ctx {
96 	if_t			 ifp;
97 	struct ifmedia		 media;
98 	u_char			 eaddr[ETHER_ADDR_LEN];
99 	int			 num_queues;
100 	struct ntb_net_queue	*queues;
101 	int			 mtu;
102 };
103 
104 static int ntb_net_probe(device_t dev);
105 static int ntb_net_attach(device_t dev);
106 static int ntb_net_detach(device_t dev);
107 static void ntb_net_init(void *arg);
108 static int ntb_ifmedia_upd(struct ifnet *);
109 static void ntb_ifmedia_sts(struct ifnet *, struct ifmediareq *);
110 static int ntb_ioctl(if_t ifp, u_long command, caddr_t data);
111 static int ntb_transmit(if_t ifp, struct mbuf *m);
112 static void ntb_net_tx_handler(struct ntb_transport_qp *qp, void *qp_data,
113     void *data, int len);
114 static void ntb_net_rx_handler(struct ntb_transport_qp *qp, void *qp_data,
115     void *data, int len);
116 static void ntb_net_event_handler(void *data, enum ntb_link_event status);
117 static void ntb_handle_tx(void *arg, int pending);
118 static void ntb_qp_full(void *arg);
119 static void ntb_qflush(if_t ifp);
120 static void create_random_local_eui48(u_char *eaddr);
121 
122 static int
123 ntb_net_probe(device_t dev)
124 {
125 
126 	device_set_desc(dev, "NTB Network Interface");
127 	return (0);
128 }
129 
130 static int
131 ntb_net_attach(device_t dev)
132 {
133 	struct ntb_net_ctx *sc = device_get_softc(dev);
134 	struct ntb_net_queue *q;
135 	if_t ifp;
136 	struct ntb_queue_handlers handlers = { ntb_net_rx_handler,
137 	    ntb_net_tx_handler, ntb_net_event_handler };
138 	int i;
139 
140 	ifp = sc->ifp = if_gethandle(IFT_ETHER);
141 	if (ifp == NULL) {
142 		printf("ntb: Cannot allocate ifnet structure\n");
143 		return (ENOMEM);
144 	}
145 	if_initname(ifp, device_get_name(dev), device_get_unit(dev));
146 	if_setdev(ifp, dev);
147 
148 	sc->num_queues = min(g_if_ntb_num_queues,
149 	    ntb_transport_queue_count(dev));
150 	sc->queues = malloc(sc->num_queues * sizeof(struct ntb_net_queue),
151 	    M_DEVBUF, M_WAITOK | M_ZERO);
152 	sc->mtu = INT_MAX;
153 	for (i = 0; i < sc->num_queues; i++) {
154 		q = &sc->queues[i];
155 		q->sc = sc;
156 		q->ifp = ifp;
157 		q->qp = ntb_transport_create_queue(dev, i, &handlers, q);
158 		if (q->qp == NULL)
159 			break;
160 		sc->mtu = imin(sc->mtu, ntb_transport_max_size(q->qp));
161 		mtx_init(&q->tx_lock, "ntb tx", NULL, MTX_DEF);
162 		q->br = buf_ring_alloc(4096, M_DEVBUF, M_WAITOK, &q->tx_lock);
163 		TASK_INIT(&q->tx_task, 0, ntb_handle_tx, q);
164 		q->tx_tq = taskqueue_create_fast("ntb_txq", M_NOWAIT,
165 		    taskqueue_thread_enqueue, &q->tx_tq);
166 		taskqueue_start_threads(&q->tx_tq, 1, PI_NET, "%s txq%d",
167 		    device_get_nameunit(dev), i);
168 		callout_init(&q->queue_full, 1);
169 	}
170 	sc->num_queues = i;
171 	device_printf(dev, "%d queue(s)\n", sc->num_queues);
172 
173 	if_setinitfn(ifp, ntb_net_init);
174 	if_setsoftc(ifp, sc);
175 	if_setflags(ifp, IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST);
176 	if_setioctlfn(ifp, ntb_ioctl);
177 	if_settransmitfn(ifp, ntb_transmit);
178 	if_setqflushfn(ifp, ntb_qflush);
179 	create_random_local_eui48(sc->eaddr);
180 	ether_ifattach(ifp, sc->eaddr);
181 	if_setcapabilities(ifp, IFCAP_HWCSUM | IFCAP_HWCSUM_IPV6 |
182 	    IFCAP_JUMBO_MTU | IFCAP_LINKSTATE);
183 	if_setcapenable(ifp, IFCAP_JUMBO_MTU | IFCAP_LINKSTATE);
184 	if_setmtu(ifp, sc->mtu - ETHER_HDR_LEN);
185 
186 	ifmedia_init(&sc->media, IFM_IMASK, ntb_ifmedia_upd,
187 	    ntb_ifmedia_sts);
188 	ifmedia_add(&sc->media, NTB_MEDIATYPE, 0, NULL);
189 	ifmedia_set(&sc->media, NTB_MEDIATYPE);
190 
191 	for (i = 0; i < sc->num_queues; i++)
192 		ntb_transport_link_up(sc->queues[i].qp);
193 	return (0);
194 }
195 
196 static int
197 ntb_net_detach(device_t dev)
198 {
199 	struct ntb_net_ctx *sc = device_get_softc(dev);
200 	struct ntb_net_queue *q;
201 	int i;
202 
203 	for (i = 0; i < sc->num_queues; i++)
204 		ntb_transport_link_down(sc->queues[i].qp);
205 	ether_ifdetach(sc->ifp);
206 	if_free(sc->ifp);
207 	ifmedia_removeall(&sc->media);
208 	for (i = 0; i < sc->num_queues; i++) {
209 		q = &sc->queues[i];
210 		ntb_transport_free_queue(q->qp);
211 		buf_ring_free(q->br, M_DEVBUF);
212 		callout_drain(&q->queue_full);
213 		taskqueue_drain_all(q->tx_tq);
214 		mtx_destroy(&q->tx_lock);
215 	}
216 	free(sc->queues, M_DEVBUF);
217 	return (0);
218 }
219 
220 /* Network device interface */
221 
222 static void
223 ntb_net_init(void *arg)
224 {
225 	struct ntb_net_ctx *sc = arg;
226 	if_t ifp = sc->ifp;
227 
228 	if_setdrvflagbits(ifp, IFF_DRV_RUNNING, IFF_DRV_OACTIVE);
229 	if_setbaudrate(ifp, ntb_transport_link_speed(sc->queues[0].qp));
230 	if_link_state_change(ifp, ntb_transport_link_query(sc->queues[0].qp) ?
231 	    LINK_STATE_UP : LINK_STATE_DOWN);
232 }
233 
234 static int
235 ntb_ioctl(if_t ifp, u_long command, caddr_t data)
236 {
237 	struct ntb_net_ctx *sc = if_getsoftc(ifp);
238 	struct ifreq *ifr = (struct ifreq *)data;
239 	int error = 0;
240 
241 	switch (command) {
242 	case SIOCSIFFLAGS:
243 	case SIOCADDMULTI:
244 	case SIOCDELMULTI:
245 		break;
246 
247 	case SIOCSIFMTU:
248 	    {
249 		if (ifr->ifr_mtu > sc->mtu - ETHER_HDR_LEN) {
250 			error = EINVAL;
251 			break;
252 		}
253 
254 		if_setmtu(ifp, ifr->ifr_mtu);
255 		break;
256 	    }
257 
258 	case SIOCSIFMEDIA:
259 	case SIOCGIFMEDIA:
260 		error = ifmedia_ioctl(ifp, ifr, &sc->media, command);
261 		break;
262 
263 	case SIOCSIFCAP:
264 		if (ifr->ifr_reqcap & IFCAP_RXCSUM)
265 			if_setcapenablebit(ifp, IFCAP_RXCSUM, 0);
266 		else
267 			if_setcapenablebit(ifp, 0, IFCAP_RXCSUM);
268 		if (ifr->ifr_reqcap & IFCAP_TXCSUM) {
269 			if_setcapenablebit(ifp, IFCAP_TXCSUM, 0);
270 			if_sethwassistbits(ifp, NTB_CSUM_FEATURES, 0);
271 		} else {
272 			if_setcapenablebit(ifp, 0, IFCAP_TXCSUM);
273 			if_sethwassistbits(ifp, 0, NTB_CSUM_FEATURES);
274 		}
275 		if (ifr->ifr_reqcap & IFCAP_RXCSUM_IPV6)
276 			if_setcapenablebit(ifp, IFCAP_RXCSUM_IPV6, 0);
277 		else
278 			if_setcapenablebit(ifp, 0, IFCAP_RXCSUM_IPV6);
279 		if (ifr->ifr_reqcap & IFCAP_TXCSUM_IPV6) {
280 			if_setcapenablebit(ifp, IFCAP_TXCSUM_IPV6, 0);
281 			if_sethwassistbits(ifp, NTB_CSUM_FEATURES6, 0);
282 		} else {
283 			if_setcapenablebit(ifp, 0, IFCAP_TXCSUM_IPV6);
284 			if_sethwassistbits(ifp, 0, NTB_CSUM_FEATURES6);
285 		}
286 		break;
287 
288 	default:
289 		error = ether_ioctl(ifp, command, data);
290 		break;
291 	}
292 
293 	return (error);
294 }
295 
296 static int
297 ntb_ifmedia_upd(struct ifnet *ifp)
298 {
299 	struct ntb_net_ctx *sc = if_getsoftc(ifp);
300 	struct ifmedia *ifm = &sc->media;
301 
302 	if (IFM_TYPE(ifm->ifm_media) != IFM_ETHER)
303 		return (EINVAL);
304 
305 	return (0);
306 }
307 
308 static void
309 ntb_ifmedia_sts(struct ifnet *ifp, struct ifmediareq *ifmr)
310 {
311 	struct ntb_net_ctx *sc = if_getsoftc(ifp);
312 
313 	ifmr->ifm_status = IFM_AVALID;
314 	ifmr->ifm_active = NTB_MEDIATYPE;
315 	if (ntb_transport_link_query(sc->queues[0].qp))
316 		ifmr->ifm_status |= IFM_ACTIVE;
317 }
318 
319 static void
320 ntb_transmit_locked(struct ntb_net_queue *q)
321 {
322 	if_t ifp = q->ifp;
323 	struct mbuf *m;
324 	int rc, len;
325 	short mflags;
326 
327 	CTR0(KTR_NTB, "TX: ntb_transmit_locked");
328 	while ((m = drbr_peek(ifp, q->br)) != NULL) {
329 		CTR1(KTR_NTB, "TX: start mbuf %p", m);
330 		if_etherbpfmtap(ifp, m);
331 		len = m->m_pkthdr.len;
332 		mflags = m->m_flags;
333 		rc = ntb_transport_tx_enqueue(q->qp, m, m, len);
334 		if (rc != 0) {
335 			CTR2(KTR_NTB, "TX: could not tx mbuf %p: %d", m, rc);
336 			if (rc == EAGAIN) {
337 				drbr_putback(ifp, q->br, m);
338 				callout_reset_sbt(&q->queue_full,
339 				    SBT_1MS / 4, SBT_1MS / 4,
340 				    ntb_qp_full, q, 0);
341 			} else {
342 				m_freem(m);
343 				drbr_advance(ifp, q->br);
344 				if_inc_counter(ifp, IFCOUNTER_OERRORS, 1);
345 			}
346 			break;
347 		}
348 		drbr_advance(ifp, q->br);
349 		if_inc_counter(ifp, IFCOUNTER_OPACKETS, 1);
350 		if_inc_counter(ifp, IFCOUNTER_OBYTES, len);
351 		if (mflags & M_MCAST)
352 			if_inc_counter(ifp, IFCOUNTER_OMCASTS, 1);
353 	}
354 }
355 
356 static int
357 ntb_transmit(if_t ifp, struct mbuf *m)
358 {
359 	struct ntb_net_ctx *sc = if_getsoftc(ifp);
360 	struct ntb_net_queue *q;
361 	int error, i;
362 
363 	CTR0(KTR_NTB, "TX: ntb_transmit");
364 	if (M_HASHTYPE_GET(m) != M_HASHTYPE_NONE)
365 		i = m->m_pkthdr.flowid % sc->num_queues;
366 	else
367 		i = curcpu % sc->num_queues;
368 	q = &sc->queues[i];
369 
370 	error = drbr_enqueue(ifp, q->br, m);
371 	if (error)
372 		return (error);
373 
374 	if (mtx_trylock(&q->tx_lock)) {
375 		ntb_transmit_locked(q);
376 		mtx_unlock(&q->tx_lock);
377 	} else
378 		taskqueue_enqueue(q->tx_tq, &q->tx_task);
379 	return (0);
380 }
381 
382 static void
383 ntb_handle_tx(void *arg, int pending)
384 {
385 	struct ntb_net_queue *q = arg;
386 
387 	mtx_lock(&q->tx_lock);
388 	ntb_transmit_locked(q);
389 	mtx_unlock(&q->tx_lock);
390 }
391 
392 static void
393 ntb_qp_full(void *arg)
394 {
395 	struct ntb_net_queue *q = arg;
396 
397 	CTR0(KTR_NTB, "TX: qp_full callout");
398 	if (ntb_transport_tx_free_entry(q->qp) > 0)
399 		taskqueue_enqueue(q->tx_tq, &q->tx_task);
400 	else
401 		callout_schedule_sbt(&q->queue_full,
402 		    SBT_1MS / 4, SBT_1MS / 4, 0);
403 }
404 
405 static void
406 ntb_qflush(if_t ifp)
407 {
408 	struct ntb_net_ctx *sc = if_getsoftc(ifp);
409 	struct ntb_net_queue *q;
410 	struct mbuf *m;
411 	int i;
412 
413 	for (i = 0; i < sc->num_queues; i++) {
414 		q = &sc->queues[i];
415 		mtx_lock(&q->tx_lock);
416 		while ((m = buf_ring_dequeue_sc(q->br)) != NULL)
417 			m_freem(m);
418 		mtx_unlock(&q->tx_lock);
419 	}
420 	if_qflush(ifp);
421 }
422 
423 /* Network Device Callbacks */
424 static void
425 ntb_net_tx_handler(struct ntb_transport_qp *qp, void *qp_data, void *data,
426     int len)
427 {
428 
429 	m_freem(data);
430 	CTR1(KTR_NTB, "TX: tx_handler freeing mbuf %p", data);
431 }
432 
433 static void
434 ntb_net_rx_handler(struct ntb_transport_qp *qp, void *qp_data, void *data,
435     int len)
436 {
437 	struct ntb_net_queue *q = qp_data;
438 	struct ntb_net_ctx *sc = q->sc;
439 	struct mbuf *m = data;
440 	if_t ifp = q->ifp;
441 	uint16_t proto;
442 
443 	CTR1(KTR_NTB, "RX: rx handler (%d)", len);
444 	if (len < 0) {
445 		if_inc_counter(ifp, IFCOUNTER_IERRORS, 1);
446 		return;
447 	}
448 
449 	m->m_pkthdr.rcvif = ifp;
450 	if (sc->num_queues > 1) {
451 		m->m_pkthdr.flowid = q - sc->queues;
452 		M_HASHTYPE_SET(m, M_HASHTYPE_OPAQUE);
453 	}
454 	if (if_getcapenable(ifp) & (IFCAP_RXCSUM | IFCAP_RXCSUM_IPV6)) {
455 		m_copydata(m, 12, 2, (void *)&proto);
456 		switch (ntohs(proto)) {
457 		case ETHERTYPE_IP:
458 			if (if_getcapenable(ifp) & IFCAP_RXCSUM) {
459 				m->m_pkthdr.csum_data = 0xffff;
460 				m->m_pkthdr.csum_flags = NTB_CSUM_SET;
461 			}
462 			break;
463 		case ETHERTYPE_IPV6:
464 			if (if_getcapenable(ifp) & IFCAP_RXCSUM_IPV6) {
465 				m->m_pkthdr.csum_data = 0xffff;
466 				m->m_pkthdr.csum_flags = NTB_CSUM_SET;
467 			}
468 			break;
469 		}
470 	}
471 	if_inc_counter(ifp, IFCOUNTER_IPACKETS, 1);
472 	if_input(ifp, m);
473 }
474 
475 static void
476 ntb_net_event_handler(void *data, enum ntb_link_event status)
477 {
478 	struct ntb_net_queue *q = data;
479 
480 	if_setbaudrate(q->ifp, ntb_transport_link_speed(q->qp));
481 	if_link_state_change(q->ifp, (status == NTB_LINK_UP) ? LINK_STATE_UP :
482 	    LINK_STATE_DOWN);
483 }
484 
485 /* Helper functions */
486 /* TODO: This too should really be part of the kernel */
487 #define EUI48_MULTICAST			1 << 0
488 #define EUI48_LOCALLY_ADMINISTERED	1 << 1
489 static void
490 create_random_local_eui48(u_char *eaddr)
491 {
492 	static uint8_t counter = 0;
493 
494 	eaddr[0] = EUI48_LOCALLY_ADMINISTERED;
495 	arc4rand(&eaddr[1], 4, 0);
496 	eaddr[5] = counter++;
497 }
498 
499 static device_method_t ntb_net_methods[] = {
500 	/* Device interface */
501 	DEVMETHOD(device_probe,     ntb_net_probe),
502 	DEVMETHOD(device_attach,    ntb_net_attach),
503 	DEVMETHOD(device_detach,    ntb_net_detach),
504 	DEVMETHOD_END
505 };
506 
507 devclass_t ntb_net_devclass;
508 static DEFINE_CLASS_0(ntb, ntb_net_driver, ntb_net_methods,
509     sizeof(struct ntb_net_ctx));
510 DRIVER_MODULE(if_ntb, ntb_transport, ntb_net_driver, ntb_net_devclass,
511     NULL, NULL);
512 MODULE_DEPEND(if_ntb, ntb_transport, 1, 1, 1);
513 MODULE_VERSION(if_ntb, 1);
514