xref: /freebsd/sys/dev/cxgbe/t4_tracer.c (revision b2d48be1bc7df45ddd13b143a160d0acb5a383c5)
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 		return (0);
129 	if (name[5] < '0' || name[5] > '9')
130 		return (0);
131 	return (1);
132 }
133 
134 static int
135 t4_cloner_create(struct if_clone *ifc, char *name, size_t len, caddr_t params)
136 {
137 	struct match_rr mrr;
138 	struct adapter *sc;
139 	struct ifnet *ifp;
140 	int rc, unit;
141 	const uint8_t lla[ETHER_ADDR_LEN] = {0, 0, 0, 0, 0, 0};
142 
143 	mrr.name = name;
144 	mrr.lock = 1;
145 	mrr.sc = NULL;
146 	mrr.rc = ENOENT;
147 	t4_iterate(match_name, &mrr);
148 
149 	if (mrr.rc != 0)
150 		return (mrr.rc);
151 	sc = mrr.sc;
152 
153 	KASSERT(sc != NULL, ("%s: name (%s) matched but softc is NULL",
154 	    __func__, name));
155 	ASSERT_SYNCHRONIZED_OP(sc);
156 
157 	sx_xlock(&t4_trace_lock);
158 
159 	if (sc->ifp != NULL) {
160 		rc = EEXIST;
161 		goto done;
162 	}
163 	if (sc->traceq < 0) {
164 		rc = EAGAIN;
165 		goto done;
166 	}
167 
168 
169 	unit = -1;
170 	rc = ifc_alloc_unit(ifc, &unit);
171 	if (rc != 0)
172 		goto done;
173 
174 	ifp = if_alloc(IFT_ETHER);
175 	if (ifp == NULL) {
176 		ifc_free_unit(ifc, unit);
177 		rc = ENOMEM;
178 		goto done;
179 	}
180 
181 	/* Note that if_xname is not <if_dname><if_dunit>. */
182 	strlcpy(ifp->if_xname, name, sizeof(ifp->if_xname));
183 	ifp->if_dname = t4_cloner_name;
184 	ifp->if_dunit = unit;
185 	ifp->if_init = tracer_init;
186 	ifp->if_flags = IFF_SIMPLEX | IFF_DRV_RUNNING;
187 	ifp->if_ioctl = tracer_ioctl;
188 	ifp->if_transmit = tracer_transmit;
189 	ifp->if_qflush = tracer_qflush;
190 	ifp->if_capabilities = IFCAP_JUMBO_MTU | IFCAP_VLAN_MTU;
191 	ifmedia_init(&sc->media, IFM_IMASK, tracer_media_change,
192 	    tracer_media_status);
193 	ifmedia_add(&sc->media, IFM_ETHER | IFM_FDX | IFM_NONE, 0, NULL);
194 	ifmedia_set(&sc->media, IFM_ETHER | IFM_FDX | IFM_NONE);
195 	ether_ifattach(ifp, lla);
196 
197 	mtx_lock(&sc->ifp_lock);
198 	ifp->if_softc = sc;
199 	sc->ifp = ifp;
200 	mtx_unlock(&sc->ifp_lock);
201 done:
202 	sx_xunlock(&t4_trace_lock);
203 	end_synchronized_op(sc, 0);
204 	return (rc);
205 }
206 
207 static int
208 t4_cloner_destroy(struct if_clone *ifc, struct ifnet *ifp)
209 {
210 	struct adapter *sc;
211 	int unit = ifp->if_dunit;
212 
213 	sx_xlock(&t4_trace_lock);
214 	sc = ifp->if_softc;
215 	if (sc != NULL) {
216 		mtx_lock(&sc->ifp_lock);
217 		sc->ifp = NULL;
218 		ifp->if_softc = NULL;
219 		mtx_unlock(&sc->ifp_lock);
220 		ifmedia_removeall(&sc->media);
221 	}
222 	ether_ifdetach(ifp);
223 	if_free(ifp);
224 	ifc_free_unit(ifc, unit);
225 	sx_xunlock(&t4_trace_lock);
226 
227 	return (0);
228 }
229 
230 void
231 t4_tracer_modload()
232 {
233 
234 	sx_init(&t4_trace_lock, "T4/T5 tracer lock");
235 	t4_cloner = if_clone_advanced(t4_cloner_name, 0, t4_cloner_match,
236 	    t4_cloner_create, t4_cloner_destroy);
237 }
238 
239 void
240 t4_tracer_modunload()
241 {
242 
243 	if (t4_cloner != NULL) {
244 		/*
245 		 * The module is being unloaded so the nexus drivers have
246 		 * detached.  The tracing interfaces can not outlive the nexus
247 		 * (ifp->if_softc is the nexus) and must have been destroyed
248 		 * already.  XXX: but if_clone is opaque to us and we can't
249 		 * assert LIST_EMPTY(&t4_cloner->ifc_iflist) at this time.
250 		 */
251 		if_clone_detach(t4_cloner);
252 	}
253 	sx_destroy(&t4_trace_lock);
254 }
255 
256 void
257 t4_tracer_port_detach(struct adapter *sc)
258 {
259 
260 	sx_xlock(&t4_trace_lock);
261 	if (sc->ifp != NULL) {
262 		mtx_lock(&sc->ifp_lock);
263 		sc->ifp->if_softc = NULL;
264 		sc->ifp = NULL;
265 		mtx_unlock(&sc->ifp_lock);
266 	}
267 	ifmedia_removeall(&sc->media);
268 	sx_xunlock(&t4_trace_lock);
269 }
270 
271 int
272 t4_get_tracer(struct adapter *sc, struct t4_tracer *t)
273 {
274 	int rc, i, enabled;
275 	struct trace_params tp;
276 
277 	if (t->idx >= NTRACE) {
278 		t->idx = 0xff;
279 		t->enabled = 0;
280 		t->valid = 0;
281 		return (0);
282 	}
283 
284 	rc = begin_synchronized_op(sc, NULL, HOLD_LOCK | SLEEP_OK | INTR_OK,
285 	    "t4gett");
286 	if (rc)
287 		return (rc);
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
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 	/*
339 	 * If no tracing filter is specified this time then check if the filter
340 	 * at the index is valid anyway because it was set previously.  If so
341 	 * then this is a legitimate enable/disable operation.
342 	 */
343 	if (t->valid == 0) {
344 		if (isset(&sc->tracer_valid, t->idx))
345 			tpp = NULL;
346 		else
347 			rc = EINVAL;
348 		goto done;
349 	}
350 
351 	if (t->tp.port > 19 || t->tp.snap_len > 9600 ||
352 	    t->tp.min_len > M_TFMINPKTSIZE || t->tp.skip_len > M_TFLENGTH ||
353 	    t->tp.skip_ofst > M_TFOFFSET) {
354 		rc = EINVAL;
355 		goto done;
356 	}
357 
358 	memcpy(&tp.data[0], &t->tp.data[0], sizeof(tp.data));
359 	memcpy(&tp.mask[0], &t->tp.mask[0], sizeof(tp.mask));
360 	tp.snap_len = t->tp.snap_len;
361 	tp.min_len = t->tp.min_len;
362 	tp.skip_ofst = t->tp.skip_ofst;
363 	tp.skip_len = t->tp.skip_len;
364 	tp.invert = !!t->tp.invert;
365 
366 	/* convert port to channel iff 0 <= port < 8. */
367 	if (t->tp.port < 4) {
368 		if (sc->port[t->tp.port] == NULL) {
369 			rc = EINVAL;
370 			goto done;
371 		}
372 		tp.port = sc->port[t->tp.port]->tx_chan;
373 	} else if (t->tp.port < 8) {
374 		if (sc->port[t->tp.port - 4] == NULL) {
375 			rc = EINVAL;
376 			goto done;
377 		}
378 		tp.port = sc->port[t->tp.port - 4]->tx_chan + 4;
379 	}
380 	tpp = &tp;
381 done:
382 	if (rc == 0) {
383 		rc = -t4_set_trace_filter(sc, tpp, t->idx, t->enabled);
384 		if (rc == 0) {
385 			if (t->enabled) {
386 				setbit(&sc->tracer_valid, t->idx);
387 				if (sc->tracer_enabled == 0) {
388 					t4_set_reg_field(sc, A_MPS_TRC_CFG,
389 					    F_TRCEN, F_TRCEN);
390 				}
391 				setbit(&sc->tracer_enabled, t->idx);
392 			} else {
393 				clrbit(&sc->tracer_enabled, t->idx);
394 				if (sc->tracer_enabled == 0) {
395 					t4_set_reg_field(sc, A_MPS_TRC_CFG,
396 					    F_TRCEN, 0);
397 				}
398 			}
399 		}
400 	}
401 	end_synchronized_op(sc, LOCK_HELD);
402 
403 	return (rc);
404 }
405 
406 int
407 t4_trace_pkt(struct sge_iq *iq, const struct rss_header *rss, struct mbuf *m)
408 {
409 	struct adapter *sc = iq->adapter;
410 	struct ifnet *ifp;
411 
412 	KASSERT(m != NULL, ("%s: no payload with opcode %02x", __func__,
413 	    rss->opcode));
414 
415 	mtx_lock(&sc->ifp_lock);
416 	ifp = sc->ifp;
417 	if (sc->ifp) {
418 		m_adj(m, sizeof(struct cpl_trace_pkt));
419 		m->m_pkthdr.rcvif = ifp;
420 		ETHER_BPF_MTAP(ifp, m);
421 	}
422 	mtx_unlock(&sc->ifp_lock);
423 	m_freem(m);
424 
425 	return (0);
426 }
427 
428 int
429 t5_trace_pkt(struct sge_iq *iq, const struct rss_header *rss, struct mbuf *m)
430 {
431 	struct adapter *sc = iq->adapter;
432 	struct ifnet *ifp;
433 
434 	KASSERT(m != NULL, ("%s: no payload with opcode %02x", __func__,
435 	    rss->opcode));
436 
437 	mtx_lock(&sc->ifp_lock);
438 	ifp = sc->ifp;
439 	if (ifp != NULL) {
440 		m_adj(m, sizeof(struct cpl_t5_trace_pkt));
441 		m->m_pkthdr.rcvif = ifp;
442 		ETHER_BPF_MTAP(ifp, m);
443 	}
444 	mtx_unlock(&sc->ifp_lock);
445 	m_freem(m);
446 
447 	return (0);
448 }
449 
450 
451 static void
452 tracer_init(void *arg)
453 {
454 
455 	return;
456 }
457 
458 static int
459 tracer_ioctl(struct ifnet *ifp, unsigned long cmd, caddr_t data)
460 {
461 	int rc = 0;
462 	struct adapter *sc;
463 	struct ifreq *ifr = (struct ifreq *)data;
464 
465 	switch (cmd) {
466 	case SIOCSIFMTU:
467 	case SIOCSIFFLAGS:
468 	case SIOCADDMULTI:
469 	case SIOCDELMULTI:
470 	case SIOCSIFCAP:
471 		break;
472 	case SIOCSIFMEDIA:
473 	case SIOCGIFMEDIA:
474 		sx_xlock(&t4_trace_lock);
475 		sc = ifp->if_softc;
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(struct ifnet *ifp, struct mbuf *m)
491 {
492 
493 	m_freem(m);
494 	return (0);
495 }
496 
497 static void
498 tracer_qflush(struct ifnet *ifp)
499 {
500 
501 	return;
502 }
503 
504 static int
505 tracer_media_change(struct ifnet *ifp)
506 {
507 
508 	return (EOPNOTSUPP);
509 }
510 
511 static void
512 tracer_media_status(struct ifnet *ifp, struct ifmediareq *ifmr)
513 {
514 
515 	ifmr->ifm_status = IFM_AVALID | IFM_ACTIVE;
516 
517 	return;
518 }
519