xref: /freebsd/sys/dev/cxgbe/t4_tracer.c (revision 5dae51da3da0cc94d17bd67b308fad304ebec7e0)
1 /*-
2  * Copyright (c) 2013 Chelsio Communications, Inc.
3  * All rights reserved.
4  * Written by: Navdeep Parhar <np@FreeBSD.org>
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25  * SUCH DAMAGE.
26  */
27 
28 #include <sys/cdefs.h>
29 __FBSDID("$FreeBSD$");
30 
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
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 	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 	if (ifp == NULL) {
177 		ifc_free_unit(ifc, unit);
178 		rc = ENOMEM;
179 		goto done;
180 	}
181 
182 	/* Note that if_xname is not <if_dname><if_dunit>. */
183 	strlcpy(ifp->if_xname, name, sizeof(ifp->if_xname));
184 	ifp->if_dname = t4_cloner_name;
185 	ifp->if_dunit = unit;
186 	ifp->if_init = tracer_init;
187 	ifp->if_flags = IFF_SIMPLEX | IFF_DRV_RUNNING;
188 	ifp->if_ioctl = tracer_ioctl;
189 	ifp->if_transmit = tracer_transmit;
190 	ifp->if_qflush = tracer_qflush;
191 	ifp->if_capabilities = IFCAP_JUMBO_MTU | IFCAP_VLAN_MTU;
192 	ifmedia_init(&sc->media, IFM_IMASK, tracer_media_change,
193 	    tracer_media_status);
194 	ifmedia_add(&sc->media, IFM_ETHER | IFM_FDX | IFM_NONE, 0, NULL);
195 	ifmedia_set(&sc->media, IFM_ETHER | IFM_FDX | IFM_NONE);
196 	ether_ifattach(ifp, lla);
197 
198 	mtx_lock(&sc->ifp_lock);
199 	ifp->if_softc = sc;
200 	sc->ifp = ifp;
201 	mtx_unlock(&sc->ifp_lock);
202 done:
203 	sx_xunlock(&t4_trace_lock);
204 	end_synchronized_op(sc, 0);
205 	return (rc);
206 }
207 
208 static int
209 t4_cloner_destroy(struct if_clone *ifc, struct ifnet *ifp)
210 {
211 	struct adapter *sc;
212 	int unit = ifp->if_dunit;
213 
214 	sx_xlock(&t4_trace_lock);
215 	sc = ifp->if_softc;
216 	if (sc != NULL) {
217 		mtx_lock(&sc->ifp_lock);
218 		sc->ifp = NULL;
219 		ifp->if_softc = NULL;
220 		mtx_unlock(&sc->ifp_lock);
221 		ifmedia_removeall(&sc->media);
222 	}
223 	ether_ifdetach(ifp);
224 	if_free(ifp);
225 	ifc_free_unit(ifc, unit);
226 	sx_xunlock(&t4_trace_lock);
227 
228 	return (0);
229 }
230 
231 void
232 t4_tracer_modload()
233 {
234 
235 	sx_init(&t4_trace_lock, "T4/T5 tracer lock");
236 	t4_cloner = if_clone_advanced(t4_cloner_name, 0, t4_cloner_match,
237 	    t4_cloner_create, t4_cloner_destroy);
238 }
239 
240 void
241 t4_tracer_modunload()
242 {
243 
244 	if (t4_cloner != NULL) {
245 		/*
246 		 * The module is being unloaded so the nexus drivers have
247 		 * detached.  The tracing interfaces can not outlive the nexus
248 		 * (ifp->if_softc is the nexus) and must have been destroyed
249 		 * already.  XXX: but if_clone is opaque to us and we can't
250 		 * assert LIST_EMPTY(&t4_cloner->ifc_iflist) at this time.
251 		 */
252 		if_clone_detach(t4_cloner);
253 	}
254 	sx_destroy(&t4_trace_lock);
255 }
256 
257 void
258 t4_tracer_port_detach(struct adapter *sc)
259 {
260 
261 	sx_xlock(&t4_trace_lock);
262 	if (sc->ifp != NULL) {
263 		mtx_lock(&sc->ifp_lock);
264 		sc->ifp->if_softc = NULL;
265 		sc->ifp = NULL;
266 		mtx_unlock(&sc->ifp_lock);
267 	}
268 	ifmedia_removeall(&sc->media);
269 	sx_xunlock(&t4_trace_lock);
270 }
271 
272 int
273 t4_get_tracer(struct adapter *sc, struct t4_tracer *t)
274 {
275 	int rc, i, enabled;
276 	struct trace_params tp;
277 
278 	if (t->idx >= NTRACE) {
279 		t->idx = 0xff;
280 		t->enabled = 0;
281 		t->valid = 0;
282 		return (0);
283 	}
284 
285 	rc = begin_synchronized_op(sc, NULL, HOLD_LOCK | SLEEP_OK | INTR_OK,
286 	    "t4gett");
287 	if (rc)
288 		return (rc);
289 
290 	for (i = t->idx; i < NTRACE; i++) {
291 		if (isset(&sc->tracer_valid, t->idx)) {
292 			t4_get_trace_filter(sc, &tp, i, &enabled);
293 			t->idx = i;
294 			t->enabled = enabled;
295 			t->valid = 1;
296 			memcpy(&t->tp.data[0], &tp.data[0], sizeof(t->tp.data));
297 			memcpy(&t->tp.mask[0], &tp.mask[0], sizeof(t->tp.mask));
298 			t->tp.snap_len = tp.snap_len;
299 			t->tp.min_len = tp.min_len;
300 			t->tp.skip_ofst = tp.skip_ofst;
301 			t->tp.skip_len = tp.skip_len;
302 			t->tp.invert = tp.invert;
303 
304 			/* convert channel to port iff 0 <= port < 8. */
305 			if (tp.port < 4)
306 				t->tp.port = sc->chan_map[tp.port];
307 			else if (tp.port < 8)
308 				t->tp.port = sc->chan_map[tp.port - 4] + 4;
309 			else
310 				t->tp.port = tp.port;
311 
312 			goto done;
313 		}
314 	}
315 
316 	t->idx = 0xff;
317 	t->enabled = 0;
318 	t->valid = 0;
319 done:
320 	end_synchronized_op(sc, LOCK_HELD);
321 
322 	return (rc);
323 }
324 
325 int
326 t4_set_tracer(struct adapter *sc, struct t4_tracer *t)
327 {
328 	int rc;
329 	struct trace_params tp, *tpp;
330 
331 	if (t->idx >= NTRACE)
332 		return (EINVAL);
333 
334 	rc = begin_synchronized_op(sc, NULL, HOLD_LOCK | SLEEP_OK | INTR_OK,
335 	    "t4sett");
336 	if (rc)
337 		return (rc);
338 
339 	/*
340 	 * If no tracing filter is specified this time then check if the filter
341 	 * at the index is valid anyway because it was set previously.  If so
342 	 * then this is a legitimate enable/disable operation.
343 	 */
344 	if (t->valid == 0) {
345 		if (isset(&sc->tracer_valid, t->idx))
346 			tpp = NULL;
347 		else
348 			rc = EINVAL;
349 		goto done;
350 	}
351 
352 	if (t->tp.port > 19 || t->tp.snap_len > 9600 ||
353 	    t->tp.min_len > M_TFMINPKTSIZE || t->tp.skip_len > M_TFLENGTH ||
354 	    t->tp.skip_ofst > M_TFOFFSET) {
355 		rc = EINVAL;
356 		goto done;
357 	}
358 
359 	memcpy(&tp.data[0], &t->tp.data[0], sizeof(tp.data));
360 	memcpy(&tp.mask[0], &t->tp.mask[0], sizeof(tp.mask));
361 	tp.snap_len = t->tp.snap_len;
362 	tp.min_len = t->tp.min_len;
363 	tp.skip_ofst = t->tp.skip_ofst;
364 	tp.skip_len = t->tp.skip_len;
365 	tp.invert = !!t->tp.invert;
366 
367 	/* convert port to channel iff 0 <= port < 8. */
368 	if (t->tp.port < 4) {
369 		if (sc->port[t->tp.port] == NULL) {
370 			rc = EINVAL;
371 			goto done;
372 		}
373 		tp.port = sc->port[t->tp.port]->tx_chan;
374 	} else if (t->tp.port < 8) {
375 		if (sc->port[t->tp.port - 4] == NULL) {
376 			rc = EINVAL;
377 			goto done;
378 		}
379 		tp.port = sc->port[t->tp.port - 4]->tx_chan + 4;
380 	}
381 	tpp = &tp;
382 done:
383 	if (rc == 0) {
384 		rc = -t4_set_trace_filter(sc, tpp, t->idx, t->enabled);
385 		if (rc == 0) {
386 			if (t->enabled) {
387 				setbit(&sc->tracer_valid, t->idx);
388 				if (sc->tracer_enabled == 0) {
389 					t4_set_reg_field(sc, A_MPS_TRC_CFG,
390 					    F_TRCEN, F_TRCEN);
391 				}
392 				setbit(&sc->tracer_enabled, t->idx);
393 			} else {
394 				clrbit(&sc->tracer_enabled, t->idx);
395 				if (sc->tracer_enabled == 0) {
396 					t4_set_reg_field(sc, A_MPS_TRC_CFG,
397 					    F_TRCEN, 0);
398 				}
399 			}
400 		}
401 	}
402 	end_synchronized_op(sc, LOCK_HELD);
403 
404 	return (rc);
405 }
406 
407 int
408 t4_trace_pkt(struct sge_iq *iq, const struct rss_header *rss, struct mbuf *m)
409 {
410 	struct adapter *sc = iq->adapter;
411 	struct ifnet *ifp;
412 
413 	KASSERT(m != NULL, ("%s: no payload with opcode %02x", __func__,
414 	    rss->opcode));
415 
416 	mtx_lock(&sc->ifp_lock);
417 	ifp = sc->ifp;
418 	if (sc->ifp) {
419 		m_adj(m, sizeof(struct cpl_trace_pkt));
420 		m->m_pkthdr.rcvif = ifp;
421 		ETHER_BPF_MTAP(ifp, m);
422 	}
423 	mtx_unlock(&sc->ifp_lock);
424 	m_freem(m);
425 
426 	return (0);
427 }
428 
429 int
430 t5_trace_pkt(struct sge_iq *iq, const struct rss_header *rss, struct mbuf *m)
431 {
432 	struct adapter *sc = iq->adapter;
433 	struct ifnet *ifp;
434 
435 	KASSERT(m != NULL, ("%s: no payload with opcode %02x", __func__,
436 	    rss->opcode));
437 
438 	mtx_lock(&sc->ifp_lock);
439 	ifp = sc->ifp;
440 	if (ifp != NULL) {
441 		m_adj(m, sizeof(struct cpl_t5_trace_pkt));
442 		m->m_pkthdr.rcvif = ifp;
443 		ETHER_BPF_MTAP(ifp, m);
444 	}
445 	mtx_unlock(&sc->ifp_lock);
446 	m_freem(m);
447 
448 	return (0);
449 }
450 
451 
452 static void
453 tracer_init(void *arg)
454 {
455 
456 	return;
457 }
458 
459 static int
460 tracer_ioctl(struct ifnet *ifp, unsigned long cmd, caddr_t data)
461 {
462 	int rc = 0;
463 	struct adapter *sc;
464 	struct ifreq *ifr = (struct ifreq *)data;
465 
466 	switch (cmd) {
467 	case SIOCSIFMTU:
468 	case SIOCSIFFLAGS:
469 	case SIOCADDMULTI:
470 	case SIOCDELMULTI:
471 	case SIOCSIFCAP:
472 		break;
473 	case SIOCSIFMEDIA:
474 	case SIOCGIFMEDIA:
475 	case SIOCGIFXMEDIA:
476 		sx_xlock(&t4_trace_lock);
477 		sc = ifp->if_softc;
478 		if (sc == NULL)
479 			rc = EIO;
480 		else
481 			rc = ifmedia_ioctl(ifp, ifr, &sc->media, cmd);
482 		sx_xunlock(&t4_trace_lock);
483 		break;
484 	default:
485 		rc = ether_ioctl(ifp, cmd, data);
486 	}
487 
488 	return (rc);
489 }
490 
491 static int
492 tracer_transmit(struct ifnet *ifp, struct mbuf *m)
493 {
494 
495 	m_freem(m);
496 	return (0);
497 }
498 
499 static void
500 tracer_qflush(struct ifnet *ifp)
501 {
502 
503 	return;
504 }
505 
506 static int
507 tracer_media_change(struct ifnet *ifp)
508 {
509 
510 	return (EOPNOTSUPP);
511 }
512 
513 static void
514 tracer_media_status(struct ifnet *ifp, struct ifmediareq *ifmr)
515 {
516 
517 	ifmr->ifm_status = IFM_AVALID | IFM_ACTIVE;
518 
519 	return;
520 }
521