xref: /freebsd/sys/dev/cxgbe/t4_tracer.c (revision 38c63bdc46252d4d8cd313dff4183ec4546d26d9)
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(if_t, unsigned long, caddr_t);
91 static int tracer_transmit(if_t, struct mbuf *);
92 static void tracer_qflush(if_t);
93 static int tracer_media_change(if_t);
94 static void tracer_media_status(if_t, 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
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
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
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 	if_t ifp;
141 	int rc;
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 	ifp = if_alloc(IFT_ETHER);
170 	if (ifp == NULL) {
171 		rc = ENOMEM;
172 		goto done;
173 	}
174 
175 	/* Note that if_xname is identical to the nexus nameunit */
176 	if_initname(ifp, name, -1);
177 	if_setdname(ifp, t4_cloner_name);
178 	if_setinitfn(ifp, tracer_init);
179 	if_setflags(ifp, IFF_SIMPLEX | IFF_DRV_RUNNING);
180 	if_setioctlfn(ifp, tracer_ioctl);
181 	if_settransmitfn(ifp, tracer_transmit);
182 	if_setqflushfn(ifp, tracer_qflush);
183 	if_setcapabilities(ifp, IFCAP_JUMBO_MTU | IFCAP_VLAN_MTU);
184 	ifmedia_init(&sc->media, IFM_IMASK, tracer_media_change,
185 	    tracer_media_status);
186 	ifmedia_add(&sc->media, IFM_ETHER | IFM_FDX | IFM_NONE, 0, NULL);
187 	ifmedia_set(&sc->media, IFM_ETHER | IFM_FDX | IFM_NONE);
188 	sx_xunlock(&t4_trace_lock);
189 	ether_ifattach(ifp, lla);
190 	sx_xlock(&t4_trace_lock);
191 	mtx_lock(&sc->ifp_lock);
192 	if_setsoftc(ifp, sc);
193 	sc->ifp = ifp;
194 	mtx_unlock(&sc->ifp_lock);
195 	rc = 0;
196 done:
197 	sx_xunlock(&t4_trace_lock);
198 	end_synchronized_op(sc, 0);
199 	return (rc);
200 }
201 
202 static int
203 t4_cloner_destroy(struct if_clone *ifc, if_t ifp)
204 {
205 	struct adapter *sc;
206 
207 	sx_xlock(&t4_trace_lock);
208 	sc = if_getsoftc(ifp);
209 	if (sc != NULL) {
210 		mtx_lock(&sc->ifp_lock);
211 		sc->ifp = NULL;
212 		if_setsoftc(ifp, NULL);
213 		mtx_unlock(&sc->ifp_lock);
214 		ifmedia_removeall(&sc->media);
215 	}
216 	sx_xunlock(&t4_trace_lock);
217 	ether_ifdetach(ifp);
218 	if_free(ifp);
219 
220 	return (0);
221 }
222 
223 void
224 t4_tracer_modload(void)
225 {
226 
227 	sx_init(&t4_trace_lock, "T4/T5 tracer lock");
228 	t4_cloner = if_clone_advanced(t4_cloner_name, 0, t4_cloner_match,
229 	    t4_cloner_create, t4_cloner_destroy);
230 }
231 
232 void
233 t4_tracer_modunload(void)
234 {
235 
236 	if (t4_cloner != NULL) {
237 		/*
238 		 * The module is being unloaded so the nexus drivers have
239 		 * detached.  The tracing interfaces can not outlive the nexus
240 		 * (ifp->if_softc is the nexus) and must have been destroyed
241 		 * already.  XXX: but if_clone is opaque to us and we can't
242 		 * assert LIST_EMPTY(&t4_cloner->ifc_iflist) at this time.
243 		 */
244 		if_clone_detach(t4_cloner);
245 	}
246 	sx_destroy(&t4_trace_lock);
247 }
248 
249 void
250 t4_tracer_port_detach(struct adapter *sc)
251 {
252 
253 	sx_xlock(&t4_trace_lock);
254 	if (sc->ifp != NULL) {
255 		mtx_lock(&sc->ifp_lock);
256 		if_setsoftc(sc->ifp, NULL);
257 		sc->ifp = NULL;
258 		mtx_unlock(&sc->ifp_lock);
259 	}
260 	ifmedia_removeall(&sc->media);
261 	sx_xunlock(&t4_trace_lock);
262 }
263 
264 int
265 t4_get_tracer(struct adapter *sc, struct t4_tracer *t)
266 {
267 	int rc, i, enabled;
268 	struct trace_params tp;
269 
270 	if (t->idx >= NTRACE) {
271 		t->idx = 0xff;
272 		t->enabled = 0;
273 		t->valid = 0;
274 		return (0);
275 	}
276 
277 	rc = begin_synchronized_op(sc, NULL, HOLD_LOCK | SLEEP_OK | INTR_OK,
278 	    "t4gett");
279 	if (rc)
280 		return (rc);
281 
282 	if (hw_off_limits(sc)) {
283 		rc = ENXIO;
284 		goto done;
285 	}
286 
287 	for (i = t->idx; i < NTRACE; i++) {
288 		if (isset(&sc->tracer_valid, t->idx)) {
289 			t4_get_trace_filter(sc, &tp, i, &enabled);
290 			t->idx = i;
291 			t->enabled = enabled;
292 			t->valid = 1;
293 			memcpy(&t->tp.data[0], &tp.data[0], sizeof(t->tp.data));
294 			memcpy(&t->tp.mask[0], &tp.mask[0], sizeof(t->tp.mask));
295 			t->tp.snap_len = tp.snap_len;
296 			t->tp.min_len = tp.min_len;
297 			t->tp.skip_ofst = tp.skip_ofst;
298 			t->tp.skip_len = tp.skip_len;
299 			t->tp.invert = tp.invert;
300 
301 			/* convert channel to port iff 0 <= port < 8. */
302 			if (tp.port < 4)
303 				t->tp.port = sc->chan_map[tp.port];
304 			else if (tp.port < 8)
305 				t->tp.port = sc->chan_map[tp.port - 4] + 4;
306 			else
307 				t->tp.port = tp.port;
308 
309 			goto done;
310 		}
311 	}
312 
313 	t->idx = 0xff;
314 	t->enabled = 0;
315 	t->valid = 0;
316 done:
317 	end_synchronized_op(sc, LOCK_HELD);
318 
319 	return (rc);
320 }
321 
322 int
323 t4_set_tracer(struct adapter *sc, struct t4_tracer *t)
324 {
325 	int rc;
326 	struct trace_params tp, *tpp;
327 
328 	if (t->idx >= NTRACE)
329 		return (EINVAL);
330 
331 	rc = begin_synchronized_op(sc, NULL, HOLD_LOCK | SLEEP_OK | INTR_OK,
332 	    "t4sett");
333 	if (rc)
334 		return (rc);
335 
336 	if (hw_off_limits(sc)) {
337 		rc = ENXIO;
338 		goto done;
339 	}
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 	} else
383 		tp.port = t->tp.port;
384 	tpp = &tp;
385 done:
386 	if (rc == 0) {
387 		rc = -t4_set_trace_filter(sc, tpp, t->idx, t->enabled);
388 		if (rc == 0) {
389 			if (t->enabled) {
390 				setbit(&sc->tracer_valid, t->idx);
391 				if (sc->tracer_enabled == 0) {
392 					t4_set_reg_field(sc, A_MPS_TRC_CFG,
393 					    F_TRCEN, F_TRCEN);
394 				}
395 				setbit(&sc->tracer_enabled, t->idx);
396 			} else {
397 				clrbit(&sc->tracer_enabled, t->idx);
398 				if (sc->tracer_enabled == 0) {
399 					t4_set_reg_field(sc, A_MPS_TRC_CFG,
400 					    F_TRCEN, 0);
401 				}
402 			}
403 		}
404 	}
405 	end_synchronized_op(sc, LOCK_HELD);
406 
407 	return (rc);
408 }
409 
410 int
411 t4_trace_pkt(struct sge_iq *iq, const struct rss_header *rss, struct mbuf *m)
412 {
413 	struct adapter *sc = iq->adapter;
414 	if_t ifp;
415 
416 	KASSERT(m != NULL, ("%s: no payload with opcode %02x", __func__,
417 	    rss->opcode));
418 
419 	mtx_lock(&sc->ifp_lock);
420 	ifp = sc->ifp;
421 	if (sc->ifp) {
422 		m_adj(m, sizeof(struct cpl_trace_pkt));
423 		m->m_pkthdr.rcvif = ifp;
424 		ETHER_BPF_MTAP(ifp, m);
425 	}
426 	mtx_unlock(&sc->ifp_lock);
427 	m_freem(m);
428 
429 	return (0);
430 }
431 
432 int
433 t5_trace_pkt(struct sge_iq *iq, const struct rss_header *rss, struct mbuf *m)
434 {
435 	struct adapter *sc = iq->adapter;
436 	if_t ifp;
437 
438 	KASSERT(m != NULL, ("%s: no payload with opcode %02x", __func__,
439 	    rss->opcode));
440 
441 	mtx_lock(&sc->ifp_lock);
442 	ifp = sc->ifp;
443 	if (ifp != NULL) {
444 		m_adj(m, sizeof(struct cpl_t5_trace_pkt));
445 		m->m_pkthdr.rcvif = ifp;
446 		ETHER_BPF_MTAP(ifp, m);
447 	}
448 	mtx_unlock(&sc->ifp_lock);
449 	m_freem(m);
450 
451 	return (0);
452 }
453 
454 
455 static void
456 tracer_init(void *arg)
457 {
458 
459 	return;
460 }
461 
462 static int
463 tracer_ioctl(if_t ifp, unsigned long cmd, caddr_t data)
464 {
465 	int rc = 0;
466 	struct adapter *sc;
467 	struct ifreq *ifr = (struct ifreq *)data;
468 
469 	switch (cmd) {
470 	case SIOCSIFMTU:
471 	case SIOCSIFFLAGS:
472 	case SIOCADDMULTI:
473 	case SIOCDELMULTI:
474 	case SIOCSIFCAP:
475 		break;
476 	case SIOCSIFMEDIA:
477 	case SIOCGIFMEDIA:
478 	case SIOCGIFXMEDIA:
479 		sx_xlock(&t4_trace_lock);
480 		sc = if_getsoftc(ifp);
481 		if (sc == NULL)
482 			rc = EIO;
483 		else
484 			rc = ifmedia_ioctl(ifp, ifr, &sc->media, cmd);
485 		sx_xunlock(&t4_trace_lock);
486 		break;
487 	default:
488 		rc = ether_ioctl(ifp, cmd, data);
489 	}
490 
491 	return (rc);
492 }
493 
494 static int
495 tracer_transmit(if_t ifp, struct mbuf *m)
496 {
497 
498 	m_freem(m);
499 	return (0);
500 }
501 
502 static void
503 tracer_qflush(if_t ifp)
504 {
505 
506 	return;
507 }
508 
509 static int
510 tracer_media_change(if_t ifp)
511 {
512 
513 	return (EOPNOTSUPP);
514 }
515 
516 static void
517 tracer_media_status(if_t ifp, struct ifmediareq *ifmr)
518 {
519 
520 	ifmr->ifm_status = IFM_AVALID | IFM_ACTIVE;
521 
522 	return;
523 }
524