xref: /freebsd/sys/dev/cxgbe/t4_tracer.c (revision b9f654b163bce26de79705e77b872427c9f2afa1)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
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 __FBSDID("$FreeBSD$");
32 
33 #include "opt_inet.h"
34 #include "opt_inet6.h"
35 
36 #include <sys/param.h>
37 #include <sys/eventhandler.h>
38 #include <sys/lock.h>
39 #include <sys/types.h>
40 #include <sys/mbuf.h>
41 #include <sys/socket.h>
42 #include <sys/sockio.h>
43 #include <sys/sx.h>
44 #include <net/bpf.h>
45 #include <net/ethernet.h>
46 #include <net/if.h>
47 #include <net/if_clone.h>
48 #include <net/if_types.h>
49 
50 #include "common/common.h"
51 #include "common/t4_msg.h"
52 #include "common/t4_regs.h"
53 #include "t4_ioctl.h"
54 
55 /*
56  * Locking notes
57  * =============
58  *
59  * An interface cloner is registered during mod_load and it can be used to
60  * create or destroy the tracing ifnet for an adapter at any time.  It is
61  * possible for the cloned interface to outlive the adapter (adapter disappears
62  * in t4_detach but the tracing ifnet may live till mod_unload when removal of
63  * the cloner finally destroys any remaining cloned interfaces).  When tracing
64  * filters are active, this ifnet is also receiving data.  There are potential
65  * bad races between ifnet create, ifnet destroy, ifnet rx, ifnet ioctl,
66  * cxgbe_detach/t4_detach, mod_unload.
67  *
68  * a) The driver selects an iq for tracing (sc->traceq) inside a synch op.  The
69  *    iq is destroyed inside a synch op too (and sc->traceq updated).
70  * b) The cloner looks for an adapter that matches the name of the ifnet it's
71  *    been asked to create, starts a synch op on that adapter, and proceeds only
72  *    if the adapter has a tracing iq.
73  * c) The cloned ifnet and the adapter are coupled to each other via
74  *    ifp->if_softc and sc->ifp.  These can be modified only with the global
75  *    t4_trace_lock sx as well as the sc->ifp_lock mutex held.  Holding either
76  *    of these will prevent any change.
77  *
78  * The order in which all the locks involved should be acquired are:
79  * t4_list_lock
80  * adapter lock
81  * (begin synch op and let go of the above two)
82  * t4_trace_lock
83  * sc->ifp_lock
84  */
85 
86 static struct sx t4_trace_lock;
87 static const char *t4_cloner_name = "tXnex";
88 static struct if_clone *t4_cloner;
89 
90 /* tracer ifnet routines.  mostly no-ops. */
91 static void tracer_init(void *);
92 static int tracer_ioctl(struct ifnet *, unsigned long, caddr_t);
93 static int tracer_transmit(struct ifnet *, struct mbuf *);
94 static void tracer_qflush(struct ifnet *);
95 static int tracer_media_change(struct ifnet *);
96 static void tracer_media_status(struct ifnet *, struct ifmediareq *);
97 
98 /* match name (request/response) */
99 struct match_rr {
100 	const char *name;
101 	int lock;	/* set to 1 to returned sc locked. */
102 	struct adapter *sc;
103 	int rc;
104 };
105 
106 static void
107 match_name(struct adapter *sc, void *arg)
108 {
109 	struct match_rr *mrr = arg;
110 
111 	if (strcmp(device_get_nameunit(sc->dev), mrr->name) != 0)
112 		return;
113 
114 	KASSERT(mrr->sc == NULL, ("%s: multiple matches (%p, %p) for %s",
115 	    __func__, mrr->sc, sc, mrr->name));
116 
117 	mrr->sc = sc;
118 	if (mrr->lock)
119 		mrr->rc = begin_synchronized_op(mrr->sc, NULL, 0, "t4clon");
120 	else
121 		mrr->rc = 0;
122 }
123 
124 static int
125 t4_cloner_match(struct if_clone *ifc, const char *name)
126 {
127 
128 	if (strncmp(name, "t4nex", 5) != 0 &&
129 	    strncmp(name, "t5nex", 5) != 0 &&
130 	    strncmp(name, "t6nex", 5) != 0)
131 		return (0);
132 	if (name[5] < '0' || name[5] > '9')
133 		return (0);
134 	return (1);
135 }
136 
137 static int
138 t4_cloner_create(struct if_clone *ifc, char *name, size_t len, caddr_t params)
139 {
140 	struct match_rr mrr;
141 	struct adapter *sc;
142 	struct ifnet *ifp;
143 	int rc, unit;
144 	const uint8_t lla[ETHER_ADDR_LEN] = {0, 0, 0, 0, 0, 0};
145 
146 	mrr.name = name;
147 	mrr.lock = 1;
148 	mrr.sc = NULL;
149 	mrr.rc = ENOENT;
150 	t4_iterate(match_name, &mrr);
151 
152 	if (mrr.rc != 0)
153 		return (mrr.rc);
154 	sc = mrr.sc;
155 
156 	KASSERT(sc != NULL, ("%s: name (%s) matched but softc is NULL",
157 	    __func__, name));
158 	ASSERT_SYNCHRONIZED_OP(sc);
159 
160 	sx_xlock(&t4_trace_lock);
161 
162 	if (sc->ifp != NULL) {
163 		rc = EEXIST;
164 		goto done;
165 	}
166 	if (sc->traceq < 0) {
167 		rc = EAGAIN;
168 		goto done;
169 	}
170 
171 
172 	unit = -1;
173 	rc = ifc_alloc_unit(ifc, &unit);
174 	if (rc != 0)
175 		goto done;
176 
177 	ifp = if_alloc(IFT_ETHER);
178 	if (ifp == NULL) {
179 		ifc_free_unit(ifc, unit);
180 		rc = ENOMEM;
181 		goto done;
182 	}
183 
184 	/* Note that if_xname is not <if_dname><if_dunit>. */
185 	strlcpy(ifp->if_xname, name, sizeof(ifp->if_xname));
186 	ifp->if_dname = t4_cloner_name;
187 	ifp->if_dunit = unit;
188 	ifp->if_init = tracer_init;
189 	ifp->if_flags = IFF_SIMPLEX | IFF_DRV_RUNNING;
190 	ifp->if_ioctl = tracer_ioctl;
191 	ifp->if_transmit = tracer_transmit;
192 	ifp->if_qflush = tracer_qflush;
193 	ifp->if_capabilities = IFCAP_JUMBO_MTU | IFCAP_VLAN_MTU;
194 	ifmedia_init(&sc->media, IFM_IMASK, tracer_media_change,
195 	    tracer_media_status);
196 	ifmedia_add(&sc->media, IFM_ETHER | IFM_FDX | IFM_NONE, 0, NULL);
197 	ifmedia_set(&sc->media, IFM_ETHER | IFM_FDX | IFM_NONE);
198 	ether_ifattach(ifp, lla);
199 
200 	mtx_lock(&sc->ifp_lock);
201 	ifp->if_softc = sc;
202 	sc->ifp = ifp;
203 	mtx_unlock(&sc->ifp_lock);
204 done:
205 	sx_xunlock(&t4_trace_lock);
206 	end_synchronized_op(sc, 0);
207 	return (rc);
208 }
209 
210 static int
211 t4_cloner_destroy(struct if_clone *ifc, struct ifnet *ifp)
212 {
213 	struct adapter *sc;
214 	int unit = ifp->if_dunit;
215 
216 	sx_xlock(&t4_trace_lock);
217 	sc = ifp->if_softc;
218 	if (sc != NULL) {
219 		mtx_lock(&sc->ifp_lock);
220 		sc->ifp = NULL;
221 		ifp->if_softc = NULL;
222 		mtx_unlock(&sc->ifp_lock);
223 		ifmedia_removeall(&sc->media);
224 	}
225 	ether_ifdetach(ifp);
226 	if_free(ifp);
227 	ifc_free_unit(ifc, unit);
228 	sx_xunlock(&t4_trace_lock);
229 
230 	return (0);
231 }
232 
233 void
234 t4_tracer_modload()
235 {
236 
237 	sx_init(&t4_trace_lock, "T4/T5 tracer lock");
238 	t4_cloner = if_clone_advanced(t4_cloner_name, 0, t4_cloner_match,
239 	    t4_cloner_create, t4_cloner_destroy);
240 }
241 
242 void
243 t4_tracer_modunload()
244 {
245 
246 	if (t4_cloner != NULL) {
247 		/*
248 		 * The module is being unloaded so the nexus drivers have
249 		 * detached.  The tracing interfaces can not outlive the nexus
250 		 * (ifp->if_softc is the nexus) and must have been destroyed
251 		 * already.  XXX: but if_clone is opaque to us and we can't
252 		 * assert LIST_EMPTY(&t4_cloner->ifc_iflist) at this time.
253 		 */
254 		if_clone_detach(t4_cloner);
255 	}
256 	sx_destroy(&t4_trace_lock);
257 }
258 
259 void
260 t4_tracer_port_detach(struct adapter *sc)
261 {
262 
263 	sx_xlock(&t4_trace_lock);
264 	if (sc->ifp != NULL) {
265 		mtx_lock(&sc->ifp_lock);
266 		sc->ifp->if_softc = NULL;
267 		sc->ifp = NULL;
268 		mtx_unlock(&sc->ifp_lock);
269 	}
270 	ifmedia_removeall(&sc->media);
271 	sx_xunlock(&t4_trace_lock);
272 }
273 
274 int
275 t4_get_tracer(struct adapter *sc, struct t4_tracer *t)
276 {
277 	int rc, i, enabled;
278 	struct trace_params tp;
279 
280 	if (t->idx >= NTRACE) {
281 		t->idx = 0xff;
282 		t->enabled = 0;
283 		t->valid = 0;
284 		return (0);
285 	}
286 
287 	rc = begin_synchronized_op(sc, NULL, HOLD_LOCK | SLEEP_OK | INTR_OK,
288 	    "t4gett");
289 	if (rc)
290 		return (rc);
291 
292 	for (i = t->idx; i < NTRACE; i++) {
293 		if (isset(&sc->tracer_valid, t->idx)) {
294 			t4_get_trace_filter(sc, &tp, i, &enabled);
295 			t->idx = i;
296 			t->enabled = enabled;
297 			t->valid = 1;
298 			memcpy(&t->tp.data[0], &tp.data[0], sizeof(t->tp.data));
299 			memcpy(&t->tp.mask[0], &tp.mask[0], sizeof(t->tp.mask));
300 			t->tp.snap_len = tp.snap_len;
301 			t->tp.min_len = tp.min_len;
302 			t->tp.skip_ofst = tp.skip_ofst;
303 			t->tp.skip_len = tp.skip_len;
304 			t->tp.invert = tp.invert;
305 
306 			/* convert channel to port iff 0 <= port < 8. */
307 			if (tp.port < 4)
308 				t->tp.port = sc->chan_map[tp.port];
309 			else if (tp.port < 8)
310 				t->tp.port = sc->chan_map[tp.port - 4] + 4;
311 			else
312 				t->tp.port = tp.port;
313 
314 			goto done;
315 		}
316 	}
317 
318 	t->idx = 0xff;
319 	t->enabled = 0;
320 	t->valid = 0;
321 done:
322 	end_synchronized_op(sc, LOCK_HELD);
323 
324 	return (rc);
325 }
326 
327 int
328 t4_set_tracer(struct adapter *sc, struct t4_tracer *t)
329 {
330 	int rc;
331 	struct trace_params tp, *tpp;
332 
333 	if (t->idx >= NTRACE)
334 		return (EINVAL);
335 
336 	rc = begin_synchronized_op(sc, NULL, HOLD_LOCK | SLEEP_OK | INTR_OK,
337 	    "t4sett");
338 	if (rc)
339 		return (rc);
340 
341 	/*
342 	 * If no tracing filter is specified this time then check if the filter
343 	 * at the index is valid anyway because it was set previously.  If so
344 	 * then this is a legitimate enable/disable operation.
345 	 */
346 	if (t->valid == 0) {
347 		if (isset(&sc->tracer_valid, t->idx))
348 			tpp = NULL;
349 		else
350 			rc = EINVAL;
351 		goto done;
352 	}
353 
354 	if (t->tp.port > 19 || t->tp.snap_len > 9600 ||
355 	    t->tp.min_len > M_TFMINPKTSIZE || t->tp.skip_len > M_TFLENGTH ||
356 	    t->tp.skip_ofst > M_TFOFFSET) {
357 		rc = EINVAL;
358 		goto done;
359 	}
360 
361 	memcpy(&tp.data[0], &t->tp.data[0], sizeof(tp.data));
362 	memcpy(&tp.mask[0], &t->tp.mask[0], sizeof(tp.mask));
363 	tp.snap_len = t->tp.snap_len;
364 	tp.min_len = t->tp.min_len;
365 	tp.skip_ofst = t->tp.skip_ofst;
366 	tp.skip_len = t->tp.skip_len;
367 	tp.invert = !!t->tp.invert;
368 
369 	/* convert port to channel iff 0 <= port < 8. */
370 	if (t->tp.port < 4) {
371 		if (sc->port[t->tp.port] == NULL) {
372 			rc = EINVAL;
373 			goto done;
374 		}
375 		tp.port = sc->port[t->tp.port]->tx_chan;
376 	} else if (t->tp.port < 8) {
377 		if (sc->port[t->tp.port - 4] == NULL) {
378 			rc = EINVAL;
379 			goto done;
380 		}
381 		tp.port = sc->port[t->tp.port - 4]->tx_chan + 4;
382 	}
383 	tpp = &tp;
384 done:
385 	if (rc == 0) {
386 		rc = -t4_set_trace_filter(sc, tpp, t->idx, t->enabled);
387 		if (rc == 0) {
388 			if (t->enabled) {
389 				setbit(&sc->tracer_valid, t->idx);
390 				if (sc->tracer_enabled == 0) {
391 					t4_set_reg_field(sc, A_MPS_TRC_CFG,
392 					    F_TRCEN, F_TRCEN);
393 				}
394 				setbit(&sc->tracer_enabled, t->idx);
395 			} else {
396 				clrbit(&sc->tracer_enabled, t->idx);
397 				if (sc->tracer_enabled == 0) {
398 					t4_set_reg_field(sc, A_MPS_TRC_CFG,
399 					    F_TRCEN, 0);
400 				}
401 			}
402 		}
403 	}
404 	end_synchronized_op(sc, LOCK_HELD);
405 
406 	return (rc);
407 }
408 
409 int
410 t4_trace_pkt(struct sge_iq *iq, const struct rss_header *rss, struct mbuf *m)
411 {
412 	struct adapter *sc = iq->adapter;
413 	struct ifnet *ifp;
414 
415 	KASSERT(m != NULL, ("%s: no payload with opcode %02x", __func__,
416 	    rss->opcode));
417 
418 	mtx_lock(&sc->ifp_lock);
419 	ifp = sc->ifp;
420 	if (sc->ifp) {
421 		m_adj(m, sizeof(struct cpl_trace_pkt));
422 		m->m_pkthdr.rcvif = ifp;
423 		ETHER_BPF_MTAP(ifp, m);
424 	}
425 	mtx_unlock(&sc->ifp_lock);
426 	m_freem(m);
427 
428 	return (0);
429 }
430 
431 int
432 t5_trace_pkt(struct sge_iq *iq, const struct rss_header *rss, struct mbuf *m)
433 {
434 	struct adapter *sc = iq->adapter;
435 	struct ifnet *ifp;
436 
437 	KASSERT(m != NULL, ("%s: no payload with opcode %02x", __func__,
438 	    rss->opcode));
439 
440 	mtx_lock(&sc->ifp_lock);
441 	ifp = sc->ifp;
442 	if (ifp != NULL) {
443 		m_adj(m, sizeof(struct cpl_t5_trace_pkt));
444 		m->m_pkthdr.rcvif = ifp;
445 		ETHER_BPF_MTAP(ifp, m);
446 	}
447 	mtx_unlock(&sc->ifp_lock);
448 	m_freem(m);
449 
450 	return (0);
451 }
452 
453 
454 static void
455 tracer_init(void *arg)
456 {
457 
458 	return;
459 }
460 
461 static int
462 tracer_ioctl(struct ifnet *ifp, unsigned long cmd, caddr_t data)
463 {
464 	int rc = 0;
465 	struct adapter *sc;
466 	struct ifreq *ifr = (struct ifreq *)data;
467 
468 	switch (cmd) {
469 	case SIOCSIFMTU:
470 	case SIOCSIFFLAGS:
471 	case SIOCADDMULTI:
472 	case SIOCDELMULTI:
473 	case SIOCSIFCAP:
474 		break;
475 	case SIOCSIFMEDIA:
476 	case SIOCGIFMEDIA:
477 	case SIOCGIFXMEDIA:
478 		sx_xlock(&t4_trace_lock);
479 		sc = ifp->if_softc;
480 		if (sc == NULL)
481 			rc = EIO;
482 		else
483 			rc = ifmedia_ioctl(ifp, ifr, &sc->media, cmd);
484 		sx_xunlock(&t4_trace_lock);
485 		break;
486 	default:
487 		rc = ether_ioctl(ifp, cmd, data);
488 	}
489 
490 	return (rc);
491 }
492 
493 static int
494 tracer_transmit(struct ifnet *ifp, struct mbuf *m)
495 {
496 
497 	m_freem(m);
498 	return (0);
499 }
500 
501 static void
502 tracer_qflush(struct ifnet *ifp)
503 {
504 
505 	return;
506 }
507 
508 static int
509 tracer_media_change(struct ifnet *ifp)
510 {
511 
512 	return (EOPNOTSUPP);
513 }
514 
515 static void
516 tracer_media_status(struct ifnet *ifp, struct ifmediareq *ifmr)
517 {
518 
519 	ifmr->ifm_status = IFM_AVALID | IFM_ACTIVE;
520 
521 	return;
522 }
523