xref: /freebsd/sys/dev/ntb/if_ntb/if_ntb.c (revision 1db64f89363c97858961c4df0b7d02f3223723cf)
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 (ifp == NULL) {
140 		printf("ntb: Cannot allocate ifnet structure\n");
141 		return (ENOMEM);
142 	}
143 	if_initname(ifp, device_get_name(dev), device_get_unit(dev));
144 	if_setdev(ifp, dev);
145 
146 	sc->num_queues = min(g_if_ntb_num_queues,
147 	    ntb_transport_queue_count(dev));
148 	sc->queues = malloc(sc->num_queues * sizeof(struct ntb_net_queue),
149 	    M_DEVBUF, M_WAITOK | M_ZERO);
150 	sc->mtu = INT_MAX;
151 	for (i = 0; i < sc->num_queues; i++) {
152 		q = &sc->queues[i];
153 		q->sc = sc;
154 		q->ifp = ifp;
155 		q->qp = ntb_transport_create_queue(dev, i, &handlers, q);
156 		if (q->qp == NULL)
157 			break;
158 		sc->mtu = imin(sc->mtu, ntb_transport_max_size(q->qp));
159 		mtx_init(&q->tx_lock, "ntb tx", NULL, MTX_DEF);
160 		q->br = buf_ring_alloc(4096, M_DEVBUF, M_WAITOK, &q->tx_lock);
161 		TASK_INIT(&q->tx_task, 0, ntb_handle_tx, q);
162 		q->tx_tq = taskqueue_create_fast("ntb_txq", M_NOWAIT,
163 		    taskqueue_thread_enqueue, &q->tx_tq);
164 		taskqueue_start_threads(&q->tx_tq, 1, PI_NET, "%s txq%d",
165 		    device_get_nameunit(dev), i);
166 		callout_init(&q->queue_full, 1);
167 	}
168 	sc->num_queues = i;
169 	device_printf(dev, "%d queue(s)\n", sc->num_queues);
170 
171 	if_setinitfn(ifp, ntb_net_init);
172 	if_setsoftc(ifp, sc);
173 	if_setflags(ifp, IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST);
174 	if_setioctlfn(ifp, ntb_ioctl);
175 	if_settransmitfn(ifp, ntb_transmit);
176 	if_setqflushfn(ifp, ntb_qflush);
177 	create_random_local_eui48(sc->eaddr);
178 	ether_ifattach(ifp, sc->eaddr);
179 	if_setcapabilities(ifp, IFCAP_HWCSUM | IFCAP_HWCSUM_IPV6 |
180 	    IFCAP_JUMBO_MTU | IFCAP_LINKSTATE);
181 	if_setcapenable(ifp, IFCAP_JUMBO_MTU | IFCAP_LINKSTATE);
182 	if_setmtu(ifp, sc->mtu - ETHER_HDR_LEN);
183 
184 	ifmedia_init(&sc->media, IFM_IMASK, ntb_ifmedia_upd,
185 	    ntb_ifmedia_sts);
186 	ifmedia_add(&sc->media, NTB_MEDIATYPE, 0, NULL);
187 	ifmedia_set(&sc->media, NTB_MEDIATYPE);
188 
189 	for (i = 0; i < sc->num_queues; i++)
190 		ntb_transport_link_up(sc->queues[i].qp);
191 	return (0);
192 }
193 
194 static int
195 ntb_net_detach(device_t dev)
196 {
197 	struct ntb_net_ctx *sc = device_get_softc(dev);
198 	struct ntb_net_queue *q;
199 	int i;
200 
201 	for (i = 0; i < sc->num_queues; i++)
202 		ntb_transport_link_down(sc->queues[i].qp);
203 	ether_ifdetach(sc->ifp);
204 	if_free(sc->ifp);
205 	ifmedia_removeall(&sc->media);
206 	for (i = 0; i < sc->num_queues; i++) {
207 		q = &sc->queues[i];
208 		ntb_transport_free_queue(q->qp);
209 		buf_ring_free(q->br, M_DEVBUF);
210 		callout_drain(&q->queue_full);
211 		taskqueue_drain_all(q->tx_tq);
212 		mtx_destroy(&q->tx_lock);
213 	}
214 	free(sc->queues, M_DEVBUF);
215 	return (0);
216 }
217 
218 /* Network device interface */
219 
220 static void
221 ntb_net_init(void *arg)
222 {
223 	struct ntb_net_ctx *sc = arg;
224 	if_t ifp = sc->ifp;
225 
226 	if_setdrvflagbits(ifp, IFF_DRV_RUNNING, IFF_DRV_OACTIVE);
227 	if_setbaudrate(ifp, ntb_transport_link_speed(sc->queues[0].qp));
228 	if_link_state_change(ifp, ntb_transport_link_query(sc->queues[0].qp) ?
229 	    LINK_STATE_UP : LINK_STATE_DOWN);
230 }
231 
232 static int
233 ntb_ioctl(if_t ifp, u_long command, caddr_t data)
234 {
235 	struct ntb_net_ctx *sc = if_getsoftc(ifp);
236 	struct ifreq *ifr = (struct ifreq *)data;
237 	int error = 0;
238 
239 	switch (command) {
240 	case SIOCSIFFLAGS:
241 	case SIOCADDMULTI:
242 	case SIOCDELMULTI:
243 		break;
244 
245 	case SIOCSIFMTU:
246 	    {
247 		if (ifr->ifr_mtu > sc->mtu - ETHER_HDR_LEN) {
248 			error = EINVAL;
249 			break;
250 		}
251 
252 		if_setmtu(ifp, ifr->ifr_mtu);
253 		break;
254 	    }
255 
256 	case SIOCSIFMEDIA:
257 	case SIOCGIFMEDIA:
258 		error = ifmedia_ioctl(ifp, ifr, &sc->media, command);
259 		break;
260 
261 	case SIOCSIFCAP:
262 		if (ifr->ifr_reqcap & IFCAP_RXCSUM)
263 			if_setcapenablebit(ifp, IFCAP_RXCSUM, 0);
264 		else
265 			if_setcapenablebit(ifp, 0, IFCAP_RXCSUM);
266 		if (ifr->ifr_reqcap & IFCAP_TXCSUM) {
267 			if_setcapenablebit(ifp, IFCAP_TXCSUM, 0);
268 			if_sethwassistbits(ifp, NTB_CSUM_FEATURES, 0);
269 		} else {
270 			if_setcapenablebit(ifp, 0, IFCAP_TXCSUM);
271 			if_sethwassistbits(ifp, 0, NTB_CSUM_FEATURES);
272 		}
273 		if (ifr->ifr_reqcap & IFCAP_RXCSUM_IPV6)
274 			if_setcapenablebit(ifp, IFCAP_RXCSUM_IPV6, 0);
275 		else
276 			if_setcapenablebit(ifp, 0, IFCAP_RXCSUM_IPV6);
277 		if (ifr->ifr_reqcap & IFCAP_TXCSUM_IPV6) {
278 			if_setcapenablebit(ifp, IFCAP_TXCSUM_IPV6, 0);
279 			if_sethwassistbits(ifp, NTB_CSUM_FEATURES6, 0);
280 		} else {
281 			if_setcapenablebit(ifp, 0, IFCAP_TXCSUM_IPV6);
282 			if_sethwassistbits(ifp, 0, NTB_CSUM_FEATURES6);
283 		}
284 		break;
285 
286 	default:
287 		error = ether_ioctl(ifp, command, data);
288 		break;
289 	}
290 
291 	return (error);
292 }
293 
294 static int
295 ntb_ifmedia_upd(struct ifnet *ifp)
296 {
297 	struct ntb_net_ctx *sc = if_getsoftc(ifp);
298 	struct ifmedia *ifm = &sc->media;
299 
300 	if (IFM_TYPE(ifm->ifm_media) != IFM_ETHER)
301 		return (EINVAL);
302 
303 	return (0);
304 }
305 
306 static void
307 ntb_ifmedia_sts(struct ifnet *ifp, struct ifmediareq *ifmr)
308 {
309 	struct ntb_net_ctx *sc = if_getsoftc(ifp);
310 
311 	ifmr->ifm_status = IFM_AVALID;
312 	ifmr->ifm_active = NTB_MEDIATYPE;
313 	if (ntb_transport_link_query(sc->queues[0].qp))
314 		ifmr->ifm_status |= IFM_ACTIVE;
315 }
316 
317 static void
318 ntb_transmit_locked(struct ntb_net_queue *q)
319 {
320 	if_t ifp = q->ifp;
321 	struct mbuf *m;
322 	int rc, len;
323 	short mflags;
324 
325 	CTR0(KTR_NTB, "TX: ntb_transmit_locked");
326 	while ((m = drbr_peek(ifp, q->br)) != NULL) {
327 		CTR1(KTR_NTB, "TX: start mbuf %p", m);
328 		ether_bpf_mtap_if(ifp, m);
329 		len = m->m_pkthdr.len;
330 		mflags = m->m_flags;
331 		rc = ntb_transport_tx_enqueue(q->qp, m, m, len);
332 		if (rc != 0) {
333 			CTR2(KTR_NTB, "TX: could not tx mbuf %p: %d", m, rc);
334 			if (rc == EAGAIN) {
335 				drbr_putback(ifp, q->br, m);
336 				callout_reset_sbt(&q->queue_full,
337 				    SBT_1MS / 4, SBT_1MS / 4,
338 				    ntb_qp_full, q, 0);
339 			} else {
340 				m_freem(m);
341 				drbr_advance(ifp, q->br);
342 				if_inc_counter(ifp, IFCOUNTER_OERRORS, 1);
343 			}
344 			break;
345 		}
346 		drbr_advance(ifp, q->br);
347 		if_inc_counter(ifp, IFCOUNTER_OPACKETS, 1);
348 		if_inc_counter(ifp, IFCOUNTER_OBYTES, len);
349 		if (mflags & M_MCAST)
350 			if_inc_counter(ifp, IFCOUNTER_OMCASTS, 1);
351 	}
352 }
353 
354 static int
355 ntb_transmit(if_t ifp, struct mbuf *m)
356 {
357 	struct ntb_net_ctx *sc = if_getsoftc(ifp);
358 	struct ntb_net_queue *q;
359 	int error, i;
360 
361 	CTR0(KTR_NTB, "TX: ntb_transmit");
362 	if (M_HASHTYPE_GET(m) != M_HASHTYPE_NONE)
363 		i = m->m_pkthdr.flowid % sc->num_queues;
364 	else
365 		i = curcpu % sc->num_queues;
366 	q = &sc->queues[i];
367 
368 	error = drbr_enqueue(ifp, q->br, m);
369 	if (error)
370 		return (error);
371 
372 	if (mtx_trylock(&q->tx_lock)) {
373 		ntb_transmit_locked(q);
374 		mtx_unlock(&q->tx_lock);
375 	} else
376 		taskqueue_enqueue(q->tx_tq, &q->tx_task);
377 	return (0);
378 }
379 
380 static void
381 ntb_handle_tx(void *arg, int pending)
382 {
383 	struct ntb_net_queue *q = arg;
384 
385 	mtx_lock(&q->tx_lock);
386 	ntb_transmit_locked(q);
387 	mtx_unlock(&q->tx_lock);
388 }
389 
390 static void
391 ntb_qp_full(void *arg)
392 {
393 	struct ntb_net_queue *q = arg;
394 
395 	CTR0(KTR_NTB, "TX: qp_full callout");
396 	if (ntb_transport_tx_free_entry(q->qp) > 0)
397 		taskqueue_enqueue(q->tx_tq, &q->tx_task);
398 	else
399 		callout_schedule_sbt(&q->queue_full,
400 		    SBT_1MS / 4, SBT_1MS / 4, 0);
401 }
402 
403 static void
404 ntb_qflush(if_t ifp)
405 {
406 	struct ntb_net_ctx *sc = if_getsoftc(ifp);
407 	struct ntb_net_queue *q;
408 	struct mbuf *m;
409 	int i;
410 
411 	for (i = 0; i < sc->num_queues; i++) {
412 		q = &sc->queues[i];
413 		mtx_lock(&q->tx_lock);
414 		while ((m = buf_ring_dequeue_sc(q->br)) != NULL)
415 			m_freem(m);
416 		mtx_unlock(&q->tx_lock);
417 	}
418 	if_qflush(ifp);
419 }
420 
421 /* Network Device Callbacks */
422 static void
423 ntb_net_tx_handler(struct ntb_transport_qp *qp, void *qp_data, void *data,
424     int len)
425 {
426 
427 	m_freem(data);
428 	CTR1(KTR_NTB, "TX: tx_handler freeing mbuf %p", data);
429 }
430 
431 static void
432 ntb_net_rx_handler(struct ntb_transport_qp *qp, void *qp_data, void *data,
433     int len)
434 {
435 	struct ntb_net_queue *q = qp_data;
436 	struct ntb_net_ctx *sc = q->sc;
437 	struct mbuf *m = data;
438 	if_t ifp = q->ifp;
439 	uint16_t proto;
440 
441 	CTR1(KTR_NTB, "RX: rx handler (%d)", len);
442 	if (len < 0) {
443 		if_inc_counter(ifp, IFCOUNTER_IERRORS, 1);
444 		return;
445 	}
446 
447 	m->m_pkthdr.rcvif = ifp;
448 	if (sc->num_queues > 1) {
449 		m->m_pkthdr.flowid = q - sc->queues;
450 		M_HASHTYPE_SET(m, M_HASHTYPE_OPAQUE);
451 	}
452 	if (if_getcapenable(ifp) & (IFCAP_RXCSUM | IFCAP_RXCSUM_IPV6)) {
453 		m_copydata(m, 12, 2, (void *)&proto);
454 		switch (ntohs(proto)) {
455 		case ETHERTYPE_IP:
456 			if (if_getcapenable(ifp) & IFCAP_RXCSUM) {
457 				m->m_pkthdr.csum_data = 0xffff;
458 				m->m_pkthdr.csum_flags = NTB_CSUM_SET;
459 			}
460 			break;
461 		case ETHERTYPE_IPV6:
462 			if (if_getcapenable(ifp) & IFCAP_RXCSUM_IPV6) {
463 				m->m_pkthdr.csum_data = 0xffff;
464 				m->m_pkthdr.csum_flags = NTB_CSUM_SET;
465 			}
466 			break;
467 		}
468 	}
469 	if_inc_counter(ifp, IFCOUNTER_IPACKETS, 1);
470 	if_input(ifp, m);
471 }
472 
473 static void
474 ntb_net_event_handler(void *data, enum ntb_link_event status)
475 {
476 	struct ntb_net_queue *q = data;
477 
478 	if_setbaudrate(q->ifp, ntb_transport_link_speed(q->qp));
479 	if_link_state_change(q->ifp, (status == NTB_LINK_UP) ? LINK_STATE_UP :
480 	    LINK_STATE_DOWN);
481 }
482 
483 /* Helper functions */
484 /* TODO: This too should really be part of the kernel */
485 #define EUI48_MULTICAST			1 << 0
486 #define EUI48_LOCALLY_ADMINISTERED	1 << 1
487 static void
488 create_random_local_eui48(u_char *eaddr)
489 {
490 	static uint8_t counter = 0;
491 
492 	eaddr[0] = EUI48_LOCALLY_ADMINISTERED;
493 	arc4rand(&eaddr[1], 4, 0);
494 	eaddr[5] = counter++;
495 }
496 
497 static device_method_t ntb_net_methods[] = {
498 	/* Device interface */
499 	DEVMETHOD(device_probe,     ntb_net_probe),
500 	DEVMETHOD(device_attach,    ntb_net_attach),
501 	DEVMETHOD(device_detach,    ntb_net_detach),
502 	DEVMETHOD_END
503 };
504 
505 static DEFINE_CLASS_0(ntb, ntb_net_driver, ntb_net_methods,
506     sizeof(struct ntb_net_ctx));
507 DRIVER_MODULE(if_ntb, ntb_transport, ntb_net_driver, NULL, NULL);
508 MODULE_DEPEND(if_ntb, ntb_transport, 1, 1, 1);
509 MODULE_VERSION(if_ntb, 1);
510