xref: /freebsd-13-stable/sys/dev/cxgbe/t4_tracer.c (revision f500e5c6c99bd4520daa4524113462e3cf68f032)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2013 Chelsio Communications, Inc.
5  * All rights reserved.
6  * Written by: Navdeep Parhar <np@FreeBSD.org>
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  */
29 
30 #include <sys/cdefs.h>
31 #include "opt_inet.h"
32 #include "opt_inet6.h"
33 
34 #include <sys/param.h>
35 #include <sys/eventhandler.h>
36 #include <sys/lock.h>
37 #include <sys/types.h>
38 #include <sys/mbuf.h>
39 #include <sys/socket.h>
40 #include <sys/sockio.h>
41 #include <sys/sx.h>
42 #include <net/bpf.h>
43 #include <net/ethernet.h>
44 #include <net/if.h>
45 #include <net/if_clone.h>
46 #include <net/if_types.h>
47 
48 #include "common/common.h"
49 #include "common/t4_msg.h"
50 #include "common/t4_regs.h"
51 #include "t4_ioctl.h"
52 
53 /*
54  * Locking notes
55  * =============
56  *
57  * An interface cloner is registered during mod_load and it can be used to
58  * create or destroy the tracing ifnet for an adapter at any time.  It is
59  * possible for the cloned interface to outlive the adapter (adapter disappears
60  * in t4_detach but the tracing ifnet may live till mod_unload when removal of
61  * the cloner finally destroys any remaining cloned interfaces).  When tracing
62  * filters are active, this ifnet is also receiving data.  There are potential
63  * bad races between ifnet create, ifnet destroy, ifnet rx, ifnet ioctl,
64  * cxgbe_detach/t4_detach, mod_unload.
65  *
66  * a) The driver selects an iq for tracing (sc->traceq) inside a synch op.  The
67  *    iq is destroyed inside a synch op too (and sc->traceq updated).
68  * b) The cloner looks for an adapter that matches the name of the ifnet it's
69  *    been asked to create, starts a synch op on that adapter, and proceeds only
70  *    if the adapter has a tracing iq.
71  * c) The cloned ifnet and the adapter are coupled to each other via
72  *    ifp->if_softc and sc->ifp.  These can be modified only with the global
73  *    t4_trace_lock sx as well as the sc->ifp_lock mutex held.  Holding either
74  *    of these will prevent any change.
75  *
76  * The order in which all the locks involved should be acquired are:
77  * t4_list_lock
78  * adapter lock
79  * (begin synch op and let go of the above two)
80  * t4_trace_lock
81  * sc->ifp_lock
82  */
83 
84 static struct sx t4_trace_lock;
85 static const char *t4_cloner_name = "tXnex";
86 static struct if_clone *t4_cloner;
87 
88 /* tracer ifnet routines.  mostly no-ops. */
89 static void tracer_init(void *);
90 static int tracer_ioctl(struct ifnet *, unsigned long, caddr_t);
91 static int tracer_transmit(struct ifnet *, struct mbuf *);
92 static void tracer_qflush(struct ifnet *);
93 static int tracer_media_change(struct ifnet *);
94 static void tracer_media_status(struct ifnet *, struct ifmediareq *);
95 
96 /* match name (request/response) */
97 struct match_rr {
98 	const char *name;
99 	int lock;	/* set to 1 to returned sc locked. */
100 	struct adapter *sc;
101 	int rc;
102 };
103 
104 static void
match_name(struct adapter * sc,void * arg)105 match_name(struct adapter *sc, void *arg)
106 {
107 	struct match_rr *mrr = arg;
108 
109 	if (strcmp(device_get_nameunit(sc->dev), mrr->name) != 0)
110 		return;
111 
112 	KASSERT(mrr->sc == NULL, ("%s: multiple matches (%p, %p) for %s",
113 	    __func__, mrr->sc, sc, mrr->name));
114 
115 	mrr->sc = sc;
116 	if (mrr->lock)
117 		mrr->rc = begin_synchronized_op(mrr->sc, NULL, 0, "t4clon");
118 	else
119 		mrr->rc = 0;
120 }
121 
122 static int
t4_cloner_match(struct if_clone * ifc,const char * name)123 t4_cloner_match(struct if_clone *ifc, const char *name)
124 {
125 
126 	if (strncmp(name, "t4nex", 5) != 0 &&
127 	    strncmp(name, "t5nex", 5) != 0 &&
128 	    strncmp(name, "t6nex", 5) != 0)
129 		return (0);
130 	if (name[5] < '0' || name[5] > '9')
131 		return (0);
132 	return (1);
133 }
134 
135 static int
t4_cloner_create(struct if_clone * ifc,char * name,size_t len,caddr_t params)136 t4_cloner_create(struct if_clone *ifc, char *name, size_t len, caddr_t params)
137 {
138 	struct match_rr mrr;
139 	struct adapter *sc;
140 	struct ifnet *ifp;
141 	int rc, unit;
142 	const uint8_t lla[ETHER_ADDR_LEN] = {0, 0, 0, 0, 0, 0};
143 
144 	mrr.name = name;
145 	mrr.lock = 1;
146 	mrr.sc = NULL;
147 	mrr.rc = ENOENT;
148 	t4_iterate(match_name, &mrr);
149 
150 	if (mrr.rc != 0)
151 		return (mrr.rc);
152 	sc = mrr.sc;
153 
154 	KASSERT(sc != NULL, ("%s: name (%s) matched but softc is NULL",
155 	    __func__, name));
156 	ASSERT_SYNCHRONIZED_OP(sc);
157 
158 	sx_xlock(&t4_trace_lock);
159 
160 	if (sc->ifp != NULL) {
161 		rc = EEXIST;
162 		goto done;
163 	}
164 	if (sc->traceq < 0) {
165 		rc = EAGAIN;
166 		goto done;
167 	}
168 
169 
170 	unit = -1;
171 	rc = ifc_alloc_unit(ifc, &unit);
172 	if (rc != 0)
173 		goto done;
174 
175 	ifp = if_alloc(IFT_ETHER);
176 	/* Note that if_xname is not <if_dname><if_dunit>. */
177 	strlcpy(ifp->if_xname, name, sizeof(ifp->if_xname));
178 	ifp->if_dname = t4_cloner_name;
179 	ifp->if_dunit = unit;
180 	ifp->if_init = tracer_init;
181 	ifp->if_flags = IFF_SIMPLEX | IFF_DRV_RUNNING;
182 	ifp->if_ioctl = tracer_ioctl;
183 	ifp->if_transmit = tracer_transmit;
184 	ifp->if_qflush = tracer_qflush;
185 	ifp->if_capabilities = IFCAP_JUMBO_MTU | IFCAP_VLAN_MTU;
186 	ifmedia_init(&sc->media, IFM_IMASK, tracer_media_change,
187 	    tracer_media_status);
188 	ifmedia_add(&sc->media, IFM_ETHER | IFM_FDX | IFM_NONE, 0, NULL);
189 	ifmedia_set(&sc->media, IFM_ETHER | IFM_FDX | IFM_NONE);
190 	ether_ifattach(ifp, lla);
191 
192 	mtx_lock(&sc->ifp_lock);
193 	ifp->if_softc = sc;
194 	sc->ifp = ifp;
195 	mtx_unlock(&sc->ifp_lock);
196 done:
197 	sx_xunlock(&t4_trace_lock);
198 	end_synchronized_op(sc, 0);
199 	return (rc);
200 }
201 
202 static int
t4_cloner_destroy(struct if_clone * ifc,struct ifnet * ifp)203 t4_cloner_destroy(struct if_clone *ifc, struct ifnet *ifp)
204 {
205 	struct adapter *sc;
206 	int unit = ifp->if_dunit;
207 
208 	sx_xlock(&t4_trace_lock);
209 	sc = ifp->if_softc;
210 	if (sc != NULL) {
211 		mtx_lock(&sc->ifp_lock);
212 		sc->ifp = NULL;
213 		ifp->if_softc = NULL;
214 		mtx_unlock(&sc->ifp_lock);
215 		ifmedia_removeall(&sc->media);
216 	}
217 	ether_ifdetach(ifp);
218 	if_free(ifp);
219 	ifc_free_unit(ifc, unit);
220 	sx_xunlock(&t4_trace_lock);
221 
222 	return (0);
223 }
224 
225 void
t4_tracer_modload(void)226 t4_tracer_modload(void)
227 {
228 
229 	sx_init(&t4_trace_lock, "T4/T5 tracer lock");
230 	t4_cloner = if_clone_advanced(t4_cloner_name, 0, t4_cloner_match,
231 	    t4_cloner_create, t4_cloner_destroy);
232 }
233 
234 void
t4_tracer_modunload(void)235 t4_tracer_modunload(void)
236 {
237 
238 	if (t4_cloner != NULL) {
239 		/*
240 		 * The module is being unloaded so the nexus drivers have
241 		 * detached.  The tracing interfaces can not outlive the nexus
242 		 * (ifp->if_softc is the nexus) and must have been destroyed
243 		 * already.  XXX: but if_clone is opaque to us and we can't
244 		 * assert LIST_EMPTY(&t4_cloner->ifc_iflist) at this time.
245 		 */
246 		if_clone_detach(t4_cloner);
247 	}
248 	sx_destroy(&t4_trace_lock);
249 }
250 
251 void
t4_tracer_port_detach(struct adapter * sc)252 t4_tracer_port_detach(struct adapter *sc)
253 {
254 
255 	sx_xlock(&t4_trace_lock);
256 	if (sc->ifp != NULL) {
257 		mtx_lock(&sc->ifp_lock);
258 		sc->ifp->if_softc = NULL;
259 		sc->ifp = NULL;
260 		mtx_unlock(&sc->ifp_lock);
261 	}
262 	ifmedia_removeall(&sc->media);
263 	sx_xunlock(&t4_trace_lock);
264 }
265 
266 int
t4_get_tracer(struct adapter * sc,struct t4_tracer * t)267 t4_get_tracer(struct adapter *sc, struct t4_tracer *t)
268 {
269 	int rc, i, enabled;
270 	struct trace_params tp;
271 
272 	if (t->idx >= NTRACE) {
273 		t->idx = 0xff;
274 		t->enabled = 0;
275 		t->valid = 0;
276 		return (0);
277 	}
278 
279 	rc = begin_synchronized_op(sc, NULL, HOLD_LOCK | SLEEP_OK | INTR_OK,
280 	    "t4gett");
281 	if (rc)
282 		return (rc);
283 
284 	if (hw_off_limits(sc)) {
285 		rc = ENXIO;
286 		goto done;
287 	}
288 
289 	for (i = t->idx; i < NTRACE; i++) {
290 		if (isset(&sc->tracer_valid, t->idx)) {
291 			t4_get_trace_filter(sc, &tp, i, &enabled);
292 			t->idx = i;
293 			t->enabled = enabled;
294 			t->valid = 1;
295 			memcpy(&t->tp.data[0], &tp.data[0], sizeof(t->tp.data));
296 			memcpy(&t->tp.mask[0], &tp.mask[0], sizeof(t->tp.mask));
297 			t->tp.snap_len = tp.snap_len;
298 			t->tp.min_len = tp.min_len;
299 			t->tp.skip_ofst = tp.skip_ofst;
300 			t->tp.skip_len = tp.skip_len;
301 			t->tp.invert = tp.invert;
302 
303 			/* convert channel to port iff 0 <= port < 8. */
304 			if (tp.port < 4)
305 				t->tp.port = sc->chan_map[tp.port];
306 			else if (tp.port < 8)
307 				t->tp.port = sc->chan_map[tp.port - 4] + 4;
308 			else
309 				t->tp.port = tp.port;
310 
311 			goto done;
312 		}
313 	}
314 
315 	t->idx = 0xff;
316 	t->enabled = 0;
317 	t->valid = 0;
318 done:
319 	end_synchronized_op(sc, LOCK_HELD);
320 
321 	return (rc);
322 }
323 
324 int
t4_set_tracer(struct adapter * sc,struct t4_tracer * t)325 t4_set_tracer(struct adapter *sc, struct t4_tracer *t)
326 {
327 	int rc;
328 	struct trace_params tp, *tpp;
329 
330 	if (t->idx >= NTRACE)
331 		return (EINVAL);
332 
333 	rc = begin_synchronized_op(sc, NULL, HOLD_LOCK | SLEEP_OK | INTR_OK,
334 	    "t4sett");
335 	if (rc)
336 		return (rc);
337 
338 	if (hw_off_limits(sc)) {
339 		rc = ENXIO;
340 		goto done;
341 	}
342 
343 	/*
344 	 * If no tracing filter is specified this time then check if the filter
345 	 * at the index is valid anyway because it was set previously.  If so
346 	 * then this is a legitimate enable/disable operation.
347 	 */
348 	if (t->valid == 0) {
349 		if (isset(&sc->tracer_valid, t->idx))
350 			tpp = NULL;
351 		else
352 			rc = EINVAL;
353 		goto done;
354 	}
355 
356 	if (t->tp.port > 19 || t->tp.snap_len > 9600 ||
357 	    t->tp.min_len > M_TFMINPKTSIZE || t->tp.skip_len > M_TFLENGTH ||
358 	    t->tp.skip_ofst > M_TFOFFSET) {
359 		rc = EINVAL;
360 		goto done;
361 	}
362 
363 	memcpy(&tp.data[0], &t->tp.data[0], sizeof(tp.data));
364 	memcpy(&tp.mask[0], &t->tp.mask[0], sizeof(tp.mask));
365 	tp.snap_len = t->tp.snap_len;
366 	tp.min_len = t->tp.min_len;
367 	tp.skip_ofst = t->tp.skip_ofst;
368 	tp.skip_len = t->tp.skip_len;
369 	tp.invert = !!t->tp.invert;
370 
371 	/* convert port to channel iff 0 <= port < 8. */
372 	if (t->tp.port < 4) {
373 		if (sc->port[t->tp.port] == NULL) {
374 			rc = EINVAL;
375 			goto done;
376 		}
377 		tp.port = sc->port[t->tp.port]->tx_chan;
378 	} else if (t->tp.port < 8) {
379 		if (sc->port[t->tp.port - 4] == NULL) {
380 			rc = EINVAL;
381 			goto done;
382 		}
383 		tp.port = sc->port[t->tp.port - 4]->tx_chan + 4;
384 	} else
385 		tp.port = t->tp.port;
386 	tpp = &tp;
387 done:
388 	if (rc == 0) {
389 		rc = -t4_set_trace_filter(sc, tpp, t->idx, t->enabled);
390 		if (rc == 0) {
391 			if (t->enabled) {
392 				setbit(&sc->tracer_valid, t->idx);
393 				if (sc->tracer_enabled == 0) {
394 					t4_set_reg_field(sc, A_MPS_TRC_CFG,
395 					    F_TRCEN, F_TRCEN);
396 				}
397 				setbit(&sc->tracer_enabled, t->idx);
398 			} else {
399 				clrbit(&sc->tracer_enabled, t->idx);
400 				if (sc->tracer_enabled == 0) {
401 					t4_set_reg_field(sc, A_MPS_TRC_CFG,
402 					    F_TRCEN, 0);
403 				}
404 			}
405 		}
406 	}
407 	end_synchronized_op(sc, LOCK_HELD);
408 
409 	return (rc);
410 }
411 
412 int
t4_trace_pkt(struct sge_iq * iq,const struct rss_header * rss,struct mbuf * m)413 t4_trace_pkt(struct sge_iq *iq, const struct rss_header *rss, struct mbuf *m)
414 {
415 	struct adapter *sc = iq->adapter;
416 	struct ifnet *ifp;
417 
418 	KASSERT(m != NULL, ("%s: no payload with opcode %02x", __func__,
419 	    rss->opcode));
420 
421 	mtx_lock(&sc->ifp_lock);
422 	ifp = sc->ifp;
423 	if (sc->ifp) {
424 		m_adj(m, sizeof(struct cpl_trace_pkt));
425 		m->m_pkthdr.rcvif = ifp;
426 		ETHER_BPF_MTAP(ifp, m);
427 	}
428 	mtx_unlock(&sc->ifp_lock);
429 	m_freem(m);
430 
431 	return (0);
432 }
433 
434 int
t5_trace_pkt(struct sge_iq * iq,const struct rss_header * rss,struct mbuf * m)435 t5_trace_pkt(struct sge_iq *iq, const struct rss_header *rss, struct mbuf *m)
436 {
437 	struct adapter *sc = iq->adapter;
438 	struct ifnet *ifp;
439 
440 	KASSERT(m != NULL, ("%s: no payload with opcode %02x", __func__,
441 	    rss->opcode));
442 
443 	mtx_lock(&sc->ifp_lock);
444 	ifp = sc->ifp;
445 	if (ifp != NULL) {
446 		m_adj(m, sizeof(struct cpl_t5_trace_pkt));
447 		m->m_pkthdr.rcvif = ifp;
448 		ETHER_BPF_MTAP(ifp, m);
449 	}
450 	mtx_unlock(&sc->ifp_lock);
451 	m_freem(m);
452 
453 	return (0);
454 }
455 
456 
457 static void
tracer_init(void * arg)458 tracer_init(void *arg)
459 {
460 
461 	return;
462 }
463 
464 static int
tracer_ioctl(struct ifnet * ifp,unsigned long cmd,caddr_t data)465 tracer_ioctl(struct ifnet *ifp, unsigned long cmd, caddr_t data)
466 {
467 	int rc = 0;
468 	struct adapter *sc;
469 	struct ifreq *ifr = (struct ifreq *)data;
470 
471 	switch (cmd) {
472 	case SIOCSIFMTU:
473 	case SIOCSIFFLAGS:
474 	case SIOCADDMULTI:
475 	case SIOCDELMULTI:
476 	case SIOCSIFCAP:
477 		break;
478 	case SIOCSIFMEDIA:
479 	case SIOCGIFMEDIA:
480 	case SIOCGIFXMEDIA:
481 		sx_xlock(&t4_trace_lock);
482 		sc = ifp->if_softc;
483 		if (sc == NULL)
484 			rc = EIO;
485 		else
486 			rc = ifmedia_ioctl(ifp, ifr, &sc->media, cmd);
487 		sx_xunlock(&t4_trace_lock);
488 		break;
489 	default:
490 		rc = ether_ioctl(ifp, cmd, data);
491 	}
492 
493 	return (rc);
494 }
495 
496 static int
tracer_transmit(struct ifnet * ifp,struct mbuf * m)497 tracer_transmit(struct ifnet *ifp, struct mbuf *m)
498 {
499 
500 	m_freem(m);
501 	return (0);
502 }
503 
504 static void
tracer_qflush(struct ifnet * ifp)505 tracer_qflush(struct ifnet *ifp)
506 {
507 
508 	return;
509 }
510 
511 static int
tracer_media_change(struct ifnet * ifp)512 tracer_media_change(struct ifnet *ifp)
513 {
514 
515 	return (EOPNOTSUPP);
516 }
517 
518 static void
tracer_media_status(struct ifnet * ifp,struct ifmediareq * ifmr)519 tracer_media_status(struct ifnet *ifp, struct ifmediareq *ifmr)
520 {
521 
522 	ifmr->ifm_status = IFM_AVALID | IFM_ACTIVE;
523 
524 	return;
525 }
526