xref: /freebsd/sys/dev/cxgbe/t4_tracer.c (revision b64c5a0ace59af62eff52bfe110a521dc73c937b)
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 	/* Note that if_xname is identical to the nexus nameunit */
171 	if_initname(ifp, name, -1);
172 	if_setdname(ifp, t4_cloner_name);
173 	if_setinitfn(ifp, tracer_init);
174 	if_setflags(ifp, IFF_SIMPLEX | IFF_DRV_RUNNING);
175 	if_setioctlfn(ifp, tracer_ioctl);
176 	if_settransmitfn(ifp, tracer_transmit);
177 	if_setqflushfn(ifp, tracer_qflush);
178 	if_setcapabilities(ifp, IFCAP_JUMBO_MTU | IFCAP_VLAN_MTU);
179 	ifmedia_init(&sc->media, IFM_IMASK, tracer_media_change,
180 	    tracer_media_status);
181 	ifmedia_add(&sc->media, IFM_ETHER | IFM_FDX | IFM_NONE, 0, NULL);
182 	ifmedia_set(&sc->media, IFM_ETHER | IFM_FDX | IFM_NONE);
183 	sx_xunlock(&t4_trace_lock);
184 	ether_ifattach(ifp, lla);
185 	sx_xlock(&t4_trace_lock);
186 	mtx_lock(&sc->ifp_lock);
187 	if_setsoftc(ifp, sc);
188 	sc->ifp = ifp;
189 	mtx_unlock(&sc->ifp_lock);
190 	rc = 0;
191 done:
192 	sx_xunlock(&t4_trace_lock);
193 	end_synchronized_op(sc, 0);
194 	return (rc);
195 }
196 
197 static int
198 t4_cloner_destroy(struct if_clone *ifc, if_t ifp)
199 {
200 	struct adapter *sc;
201 
202 	sx_xlock(&t4_trace_lock);
203 	sc = if_getsoftc(ifp);
204 	if (sc != NULL) {
205 		mtx_lock(&sc->ifp_lock);
206 		sc->ifp = NULL;
207 		if_setsoftc(ifp, NULL);
208 		mtx_unlock(&sc->ifp_lock);
209 		ifmedia_removeall(&sc->media);
210 	}
211 	sx_xunlock(&t4_trace_lock);
212 	ether_ifdetach(ifp);
213 	if_free(ifp);
214 
215 	return (0);
216 }
217 
218 void
219 t4_tracer_modload(void)
220 {
221 
222 	sx_init(&t4_trace_lock, "T4/T5 tracer lock");
223 	t4_cloner = if_clone_advanced(t4_cloner_name, 0, t4_cloner_match,
224 	    t4_cloner_create, t4_cloner_destroy);
225 }
226 
227 void
228 t4_tracer_modunload(void)
229 {
230 
231 	if (t4_cloner != NULL) {
232 		/*
233 		 * The module is being unloaded so the nexus drivers have
234 		 * detached.  The tracing interfaces can not outlive the nexus
235 		 * (ifp->if_softc is the nexus) and must have been destroyed
236 		 * already.  XXX: but if_clone is opaque to us and we can't
237 		 * assert LIST_EMPTY(&t4_cloner->ifc_iflist) at this time.
238 		 */
239 		if_clone_detach(t4_cloner);
240 	}
241 	sx_destroy(&t4_trace_lock);
242 }
243 
244 void
245 t4_tracer_port_detach(struct adapter *sc)
246 {
247 
248 	sx_xlock(&t4_trace_lock);
249 	if (sc->ifp != NULL) {
250 		mtx_lock(&sc->ifp_lock);
251 		if_setsoftc(sc->ifp, NULL);
252 		sc->ifp = NULL;
253 		mtx_unlock(&sc->ifp_lock);
254 	}
255 	ifmedia_removeall(&sc->media);
256 	sx_xunlock(&t4_trace_lock);
257 }
258 
259 int
260 t4_get_tracer(struct adapter *sc, struct t4_tracer *t)
261 {
262 	int rc, i, enabled;
263 	struct trace_params tp;
264 
265 	if (t->idx >= NTRACE) {
266 		t->idx = 0xff;
267 		t->enabled = 0;
268 		t->valid = 0;
269 		return (0);
270 	}
271 
272 	rc = begin_synchronized_op(sc, NULL, HOLD_LOCK | SLEEP_OK | INTR_OK,
273 	    "t4gett");
274 	if (rc)
275 		return (rc);
276 
277 	if (hw_off_limits(sc)) {
278 		rc = ENXIO;
279 		goto done;
280 	}
281 
282 	for (i = t->idx; i < NTRACE; i++) {
283 		if (isset(&sc->tracer_valid, t->idx)) {
284 			t4_get_trace_filter(sc, &tp, i, &enabled);
285 			t->idx = i;
286 			t->enabled = enabled;
287 			t->valid = 1;
288 			memcpy(&t->tp.data[0], &tp.data[0], sizeof(t->tp.data));
289 			memcpy(&t->tp.mask[0], &tp.mask[0], sizeof(t->tp.mask));
290 			t->tp.snap_len = tp.snap_len;
291 			t->tp.min_len = tp.min_len;
292 			t->tp.skip_ofst = tp.skip_ofst;
293 			t->tp.skip_len = tp.skip_len;
294 			t->tp.invert = tp.invert;
295 
296 			/* convert channel to port iff 0 <= port < 8. */
297 			if (tp.port < 4)
298 				t->tp.port = sc->chan_map[tp.port];
299 			else if (tp.port < 8)
300 				t->tp.port = sc->chan_map[tp.port - 4] + 4;
301 			else
302 				t->tp.port = tp.port;
303 
304 			goto done;
305 		}
306 	}
307 
308 	t->idx = 0xff;
309 	t->enabled = 0;
310 	t->valid = 0;
311 done:
312 	end_synchronized_op(sc, LOCK_HELD);
313 
314 	return (rc);
315 }
316 
317 int
318 t4_set_tracer(struct adapter *sc, struct t4_tracer *t)
319 {
320 	int rc;
321 	struct trace_params tp, *tpp;
322 
323 	if (t->idx >= NTRACE)
324 		return (EINVAL);
325 
326 	rc = begin_synchronized_op(sc, NULL, HOLD_LOCK | SLEEP_OK | INTR_OK,
327 	    "t4sett");
328 	if (rc)
329 		return (rc);
330 
331 	if (hw_off_limits(sc)) {
332 		rc = ENXIO;
333 		goto done;
334 	}
335 
336 	/*
337 	 * If no tracing filter is specified this time then check if the filter
338 	 * at the index is valid anyway because it was set previously.  If so
339 	 * then this is a legitimate enable/disable operation.
340 	 */
341 	if (t->valid == 0) {
342 		if (isset(&sc->tracer_valid, t->idx))
343 			tpp = NULL;
344 		else
345 			rc = EINVAL;
346 		goto done;
347 	}
348 
349 	if (t->tp.port > 19 || t->tp.snap_len > 9600 ||
350 	    t->tp.min_len > M_TFMINPKTSIZE || t->tp.skip_len > M_TFLENGTH ||
351 	    t->tp.skip_ofst > M_TFOFFSET) {
352 		rc = EINVAL;
353 		goto done;
354 	}
355 
356 	memcpy(&tp.data[0], &t->tp.data[0], sizeof(tp.data));
357 	memcpy(&tp.mask[0], &t->tp.mask[0], sizeof(tp.mask));
358 	tp.snap_len = t->tp.snap_len;
359 	tp.min_len = t->tp.min_len;
360 	tp.skip_ofst = t->tp.skip_ofst;
361 	tp.skip_len = t->tp.skip_len;
362 	tp.invert = !!t->tp.invert;
363 
364 	/* convert port to channel iff 0 <= port < 8. */
365 	if (t->tp.port < 4) {
366 		if (sc->port[t->tp.port] == NULL) {
367 			rc = EINVAL;
368 			goto done;
369 		}
370 		tp.port = sc->port[t->tp.port]->tx_chan;
371 	} else if (t->tp.port < 8) {
372 		if (sc->port[t->tp.port - 4] == NULL) {
373 			rc = EINVAL;
374 			goto done;
375 		}
376 		tp.port = sc->port[t->tp.port - 4]->tx_chan + 4;
377 	} else
378 		tp.port = t->tp.port;
379 	tpp = &tp;
380 done:
381 	if (rc == 0) {
382 		rc = -t4_set_trace_filter(sc, tpp, t->idx, t->enabled);
383 		if (rc == 0) {
384 			if (t->enabled) {
385 				setbit(&sc->tracer_valid, t->idx);
386 				if (sc->tracer_enabled == 0) {
387 					t4_set_reg_field(sc, A_MPS_TRC_CFG,
388 					    F_TRCEN, F_TRCEN);
389 				}
390 				setbit(&sc->tracer_enabled, t->idx);
391 			} else {
392 				clrbit(&sc->tracer_enabled, t->idx);
393 				if (sc->tracer_enabled == 0) {
394 					t4_set_reg_field(sc, A_MPS_TRC_CFG,
395 					    F_TRCEN, 0);
396 				}
397 			}
398 		}
399 	}
400 	end_synchronized_op(sc, LOCK_HELD);
401 
402 	return (rc);
403 }
404 
405 int
406 t4_trace_pkt(struct sge_iq *iq, const struct rss_header *rss, struct mbuf *m)
407 {
408 	struct adapter *sc = iq->adapter;
409 	if_t ifp;
410 
411 	KASSERT(m != NULL, ("%s: no payload with opcode %02x", __func__,
412 	    rss->opcode));
413 
414 	mtx_lock(&sc->ifp_lock);
415 	ifp = sc->ifp;
416 	if (sc->ifp) {
417 		m_adj(m, sizeof(struct cpl_trace_pkt));
418 		m->m_pkthdr.rcvif = ifp;
419 		ETHER_BPF_MTAP(ifp, m);
420 	}
421 	mtx_unlock(&sc->ifp_lock);
422 	m_freem(m);
423 
424 	return (0);
425 }
426 
427 int
428 t5_trace_pkt(struct sge_iq *iq, const struct rss_header *rss, struct mbuf *m)
429 {
430 	struct adapter *sc = iq->adapter;
431 	if_t ifp;
432 
433 	KASSERT(m != NULL, ("%s: no payload with opcode %02x", __func__,
434 	    rss->opcode));
435 
436 	mtx_lock(&sc->ifp_lock);
437 	ifp = sc->ifp;
438 	if (ifp != NULL) {
439 		m_adj(m, sizeof(struct cpl_t5_trace_pkt));
440 		m->m_pkthdr.rcvif = ifp;
441 		ETHER_BPF_MTAP(ifp, m);
442 	}
443 	mtx_unlock(&sc->ifp_lock);
444 	m_freem(m);
445 
446 	return (0);
447 }
448 
449 
450 static void
451 tracer_init(void *arg)
452 {
453 
454 	return;
455 }
456 
457 static int
458 tracer_ioctl(if_t ifp, unsigned long cmd, caddr_t data)
459 {
460 	int rc = 0;
461 	struct adapter *sc;
462 	struct ifreq *ifr = (struct ifreq *)data;
463 
464 	switch (cmd) {
465 	case SIOCSIFMTU:
466 	case SIOCSIFFLAGS:
467 	case SIOCADDMULTI:
468 	case SIOCDELMULTI:
469 	case SIOCSIFCAP:
470 		break;
471 	case SIOCSIFMEDIA:
472 	case SIOCGIFMEDIA:
473 	case SIOCGIFXMEDIA:
474 		sx_xlock(&t4_trace_lock);
475 		sc = if_getsoftc(ifp);
476 		if (sc == NULL)
477 			rc = EIO;
478 		else
479 			rc = ifmedia_ioctl(ifp, ifr, &sc->media, cmd);
480 		sx_xunlock(&t4_trace_lock);
481 		break;
482 	default:
483 		rc = ether_ioctl(ifp, cmd, data);
484 	}
485 
486 	return (rc);
487 }
488 
489 static int
490 tracer_transmit(if_t ifp, struct mbuf *m)
491 {
492 
493 	m_freem(m);
494 	return (0);
495 }
496 
497 static void
498 tracer_qflush(if_t ifp)
499 {
500 
501 	return;
502 }
503 
504 static int
505 tracer_media_change(if_t ifp)
506 {
507 
508 	return (EOPNOTSUPP);
509 }
510 
511 static void
512 tracer_media_status(if_t ifp, struct ifmediareq *ifmr)
513 {
514 
515 	ifmr->ifm_status = IFM_AVALID | IFM_ACTIVE;
516 
517 	return;
518 }
519