1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 
22 /*
23  * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 #include <sys/types.h>
28 #include <sys/conf.h>
29 #include <sys/id_space.h>
30 #include <sys/esunddi.h>
31 #include <sys/stat.h>
32 #include <sys/mkdev.h>
33 #include <sys/stream.h>
34 #include <sys/strsubr.h>
35 #include <sys/dlpi.h>
36 #include <sys/modhash.h>
37 #include <sys/mac.h>
38 #include <sys/mac_provider.h>
39 #include <sys/mac_impl.h>
40 #include <sys/mac_client_impl.h>
41 #include <sys/mac_client_priv.h>
42 #include <sys/mac_soft_ring.h>
43 #include <sys/dld.h>
44 #include <sys/modctl.h>
45 #include <sys/fs/dv_node.h>
46 #include <sys/thread.h>
47 #include <sys/proc.h>
48 #include <sys/callb.h>
49 #include <sys/cpuvar.h>
50 #include <sys/atomic.h>
51 #include <sys/sdt.h>
52 #include <sys/mac_flow.h>
53 #include <sys/ddi_intr_impl.h>
54 #include <sys/disp.h>
55 #include <sys/sdt.h>
56 
57 /*
58  * MAC Provider Interface.
59  *
60  * Interface for GLDv3 compatible NIC drivers.
61  */
62 
63 static void i_mac_notify_thread(void *);
64 
65 typedef void (*mac_notify_default_cb_fn_t)(mac_impl_t *);
66 
67 static const mac_notify_default_cb_fn_t mac_notify_cb_list[MAC_NNOTE] = {
68 	mac_fanout_recompute,	/* MAC_NOTE_LINK */
69 	NULL,		/* MAC_NOTE_UNICST */
70 	NULL,		/* MAC_NOTE_TX */
71 	NULL,		/* MAC_NOTE_DEVPROMISC */
72 	NULL,		/* MAC_NOTE_FASTPATH_FLUSH */
73 	NULL,		/* MAC_NOTE_SDU_SIZE */
74 	NULL,		/* MAC_NOTE_MARGIN */
75 	NULL,		/* MAC_NOTE_CAPAB_CHG */
76 	NULL		/* MAC_NOTE_LOWLINK */
77 };
78 
79 /*
80  * Driver support functions.
81  */
82 
83 /* REGISTRATION */
84 
85 mac_register_t *
86 mac_alloc(uint_t mac_version)
87 {
88 	mac_register_t *mregp;
89 
90 	/*
91 	 * Make sure there isn't a version mismatch between the driver and
92 	 * the framework.  In the future, if multiple versions are
93 	 * supported, this check could become more sophisticated.
94 	 */
95 	if (mac_version != MAC_VERSION)
96 		return (NULL);
97 
98 	mregp = kmem_zalloc(sizeof (mac_register_t), KM_SLEEP);
99 	mregp->m_version = mac_version;
100 	return (mregp);
101 }
102 
103 void
104 mac_free(mac_register_t *mregp)
105 {
106 	kmem_free(mregp, sizeof (mac_register_t));
107 }
108 
109 /*
110  * mac_register() is how drivers register new MACs with the GLDv3
111  * framework.  The mregp argument is allocated by drivers using the
112  * mac_alloc() function, and can be freed using mac_free() immediately upon
113  * return from mac_register().  Upon success (0 return value), the mhp
114  * opaque pointer becomes the driver's handle to its MAC interface, and is
115  * the argument to all other mac module entry points.
116  */
117 /* ARGSUSED */
118 int
119 mac_register(mac_register_t *mregp, mac_handle_t *mhp)
120 {
121 	mac_impl_t		*mip;
122 	mactype_t		*mtype;
123 	int			err = EINVAL;
124 	struct devnames		*dnp = NULL;
125 	uint_t			instance;
126 	boolean_t		style1_created = B_FALSE;
127 	boolean_t		style2_created = B_FALSE;
128 	char			*driver;
129 	minor_t			minor = 0;
130 
131 	/* A successful call to mac_init_ops() sets the DN_GLDV3_DRIVER flag. */
132 	if (!GLDV3_DRV(ddi_driver_major(mregp->m_dip)))
133 		return (EINVAL);
134 
135 	/* Find the required MAC-Type plugin. */
136 	if ((mtype = mactype_getplugin(mregp->m_type_ident)) == NULL)
137 		return (EINVAL);
138 
139 	/* Create a mac_impl_t to represent this MAC. */
140 	mip = kmem_cache_alloc(i_mac_impl_cachep, KM_SLEEP);
141 
142 	/*
143 	 * The mac is not ready for open yet.
144 	 */
145 	mip->mi_state_flags |= MIS_DISABLED;
146 
147 	/*
148 	 * When a mac is registered, the m_instance field can be set to:
149 	 *
150 	 *  0:	Get the mac's instance number from m_dip.
151 	 *	This is usually used for physical device dips.
152 	 *
153 	 *  [1 .. MAC_MAX_MINOR-1]: Use the value as the mac's instance number.
154 	 *	For example, when an aggregation is created with the key option,
155 	 *	"key" will be used as the instance number.
156 	 *
157 	 *  -1: Assign an instance number from [MAC_MAX_MINOR .. MAXMIN-1].
158 	 *	This is often used when a MAC of a virtual link is registered
159 	 *	(e.g., aggregation when "key" is not specified, or vnic).
160 	 *
161 	 * Note that the instance number is used to derive the mi_minor field
162 	 * of mac_impl_t, which will then be used to derive the name of kstats
163 	 * and the devfs nodes.  The first 2 cases are needed to preserve
164 	 * backward compatibility.
165 	 */
166 	switch (mregp->m_instance) {
167 	case 0:
168 		instance = ddi_get_instance(mregp->m_dip);
169 		break;
170 	case ((uint_t)-1):
171 		minor = mac_minor_hold(B_TRUE);
172 		if (minor == 0) {
173 			err = ENOSPC;
174 			goto fail;
175 		}
176 		instance = minor - 1;
177 		break;
178 	default:
179 		instance = mregp->m_instance;
180 		if (instance >= MAC_MAX_MINOR) {
181 			err = EINVAL;
182 			goto fail;
183 		}
184 		break;
185 	}
186 
187 	mip->mi_minor = (minor_t)(instance + 1);
188 	mip->mi_dip = mregp->m_dip;
189 	mip->mi_clients_list = NULL;
190 	mip->mi_nclients = 0;
191 
192 	/* Set the default IEEE Port VLAN Identifier */
193 	mip->mi_pvid = 1;
194 
195 	/* Default bridge link learning protection values */
196 	mip->mi_llimit = 1000;
197 	mip->mi_ldecay = 200;
198 
199 	driver = (char *)ddi_driver_name(mip->mi_dip);
200 
201 	/* Construct the MAC name as <drvname><instance> */
202 	(void) snprintf(mip->mi_name, sizeof (mip->mi_name), "%s%d",
203 	    driver, instance);
204 
205 	mip->mi_driver = mregp->m_driver;
206 
207 	mip->mi_type = mtype;
208 	mip->mi_margin = mregp->m_margin;
209 	mip->mi_info.mi_media = mtype->mt_type;
210 	mip->mi_info.mi_nativemedia = mtype->mt_nativetype;
211 	if (mregp->m_max_sdu <= mregp->m_min_sdu)
212 		goto fail;
213 	mip->mi_sdu_min = mregp->m_min_sdu;
214 	mip->mi_sdu_max = mregp->m_max_sdu;
215 	mip->mi_info.mi_addr_length = mip->mi_type->mt_addr_length;
216 	/*
217 	 * If the media supports a broadcast address, cache a pointer to it
218 	 * in the mac_info_t so that upper layers can use it.
219 	 */
220 	mip->mi_info.mi_brdcst_addr = mip->mi_type->mt_brdcst_addr;
221 
222 	mip->mi_v12n_level = mregp->m_v12n;
223 
224 	/*
225 	 * Copy the unicast source address into the mac_info_t, but only if
226 	 * the MAC-Type defines a non-zero address length.  We need to
227 	 * handle MAC-Types that have an address length of 0
228 	 * (point-to-point protocol MACs for example).
229 	 */
230 	if (mip->mi_type->mt_addr_length > 0) {
231 		if (mregp->m_src_addr == NULL)
232 			goto fail;
233 		mip->mi_info.mi_unicst_addr =
234 		    kmem_alloc(mip->mi_type->mt_addr_length, KM_SLEEP);
235 		bcopy(mregp->m_src_addr, mip->mi_info.mi_unicst_addr,
236 		    mip->mi_type->mt_addr_length);
237 
238 		/*
239 		 * Copy the fixed 'factory' MAC address from the immutable
240 		 * info.  This is taken to be the MAC address currently in
241 		 * use.
242 		 */
243 		bcopy(mip->mi_info.mi_unicst_addr, mip->mi_addr,
244 		    mip->mi_type->mt_addr_length);
245 
246 		/*
247 		 * At this point, we should set up the classification
248 		 * rules etc but we delay it till mac_open() so that
249 		 * the resource discovery has taken place and we
250 		 * know someone wants to use the device. Otherwise
251 		 * memory gets allocated for Rx ring structures even
252 		 * during probe.
253 		 */
254 
255 		/* Copy the destination address if one is provided. */
256 		if (mregp->m_dst_addr != NULL) {
257 			bcopy(mregp->m_dst_addr, mip->mi_dstaddr,
258 			    mip->mi_type->mt_addr_length);
259 			mip->mi_dstaddr_set = B_TRUE;
260 		}
261 	} else if (mregp->m_src_addr != NULL) {
262 		goto fail;
263 	}
264 
265 	/*
266 	 * The format of the m_pdata is specific to the plugin.  It is
267 	 * passed in as an argument to all of the plugin callbacks.  The
268 	 * driver can update this information by calling
269 	 * mac_pdata_update().
270 	 */
271 	if (mip->mi_type->mt_ops.mtops_ops & MTOPS_PDATA_VERIFY) {
272 		/*
273 		 * Verify if the supplied plugin data is valid.  Note that
274 		 * even if the caller passed in a NULL pointer as plugin data,
275 		 * we still need to verify if that's valid as the plugin may
276 		 * require plugin data to function.
277 		 */
278 		if (!mip->mi_type->mt_ops.mtops_pdata_verify(mregp->m_pdata,
279 		    mregp->m_pdata_size)) {
280 			goto fail;
281 		}
282 		if (mregp->m_pdata != NULL) {
283 			mip->mi_pdata =
284 			    kmem_alloc(mregp->m_pdata_size, KM_SLEEP);
285 			bcopy(mregp->m_pdata, mip->mi_pdata,
286 			    mregp->m_pdata_size);
287 			mip->mi_pdata_size = mregp->m_pdata_size;
288 		}
289 	} else if (mregp->m_pdata != NULL) {
290 		/*
291 		 * The caller supplied non-NULL plugin data, but the plugin
292 		 * does not recognize plugin data.
293 		 */
294 		err = EINVAL;
295 		goto fail;
296 	}
297 
298 	/*
299 	 * Register the private properties.
300 	 */
301 	mac_register_priv_prop(mip, mregp->m_priv_props,
302 	    mregp->m_priv_prop_count);
303 
304 	/*
305 	 * Stash the driver callbacks into the mac_impl_t, but first sanity
306 	 * check to make sure all mandatory callbacks are set.
307 	 */
308 	if (mregp->m_callbacks->mc_getstat == NULL ||
309 	    mregp->m_callbacks->mc_start == NULL ||
310 	    mregp->m_callbacks->mc_stop == NULL ||
311 	    mregp->m_callbacks->mc_setpromisc == NULL ||
312 	    mregp->m_callbacks->mc_multicst == NULL) {
313 		goto fail;
314 	}
315 	mip->mi_callbacks = mregp->m_callbacks;
316 
317 	if (mac_capab_get((mac_handle_t)mip, MAC_CAPAB_LEGACY,
318 	    &mip->mi_capab_legacy)) {
319 		mip->mi_state_flags |= MIS_LEGACY;
320 		mip->mi_phy_dev = mip->mi_capab_legacy.ml_dev;
321 	} else {
322 		mip->mi_phy_dev = makedevice(ddi_driver_major(mip->mi_dip),
323 		    mip->mi_minor);
324 	}
325 
326 	/*
327 	 * Allocate a notification thread. thread_create blocks for memory
328 	 * if needed, it never fails.
329 	 */
330 	mip->mi_notify_thread = thread_create(NULL, 0, i_mac_notify_thread,
331 	    mip, 0, &p0, TS_RUN, minclsyspri);
332 
333 	/*
334 	 * Initialize the capabilities
335 	 */
336 
337 	if (i_mac_capab_get((mac_handle_t)mip, MAC_CAPAB_VNIC, NULL))
338 		mip->mi_state_flags |= MIS_IS_VNIC;
339 
340 	if (i_mac_capab_get((mac_handle_t)mip, MAC_CAPAB_AGGR, NULL))
341 		mip->mi_state_flags |= MIS_IS_AGGR;
342 
343 	mac_addr_factory_init(mip);
344 
345 	/*
346 	 * Enforce the virtrualization level registered.
347 	 */
348 	if (mip->mi_v12n_level & MAC_VIRT_LEVEL1) {
349 		if (mac_init_rings(mip, MAC_RING_TYPE_RX) != 0 ||
350 		    mac_init_rings(mip, MAC_RING_TYPE_TX) != 0)
351 			goto fail;
352 
353 		/*
354 		 * The driver needs to register at least rx rings for this
355 		 * virtualization level.
356 		 */
357 		if (mip->mi_rx_groups == NULL)
358 			goto fail;
359 	}
360 
361 	/*
362 	 * The driver must set mc_unicst entry point to NULL when it advertises
363 	 * CAP_RINGS for rx groups.
364 	 */
365 	if (mip->mi_rx_groups != NULL) {
366 		if (mregp->m_callbacks->mc_unicst != NULL)
367 			goto fail;
368 	} else {
369 		if (mregp->m_callbacks->mc_unicst == NULL)
370 			goto fail;
371 	}
372 
373 	/*
374 	 * The driver must set mc_tx entry point to NULL when it advertises
375 	 * CAP_RINGS for tx rings.
376 	 */
377 	if (mip->mi_tx_groups != NULL) {
378 		if (mregp->m_callbacks->mc_tx != NULL)
379 			goto fail;
380 	} else {
381 		if (mregp->m_callbacks->mc_tx == NULL)
382 			goto fail;
383 	}
384 
385 	/*
386 	 * Initialize MAC addresses. Must be called after mac_init_rings().
387 	 */
388 	mac_init_macaddr(mip);
389 
390 	mip->mi_share_capab.ms_snum = 0;
391 	if (mip->mi_v12n_level & MAC_VIRT_HIO) {
392 		(void) mac_capab_get((mac_handle_t)mip, MAC_CAPAB_SHARES,
393 		    &mip->mi_share_capab);
394 	}
395 
396 	/*
397 	 * Initialize the kstats for this device.
398 	 */
399 	mac_stat_create(mip);
400 
401 	/* Zero out any properties. */
402 	bzero(&mip->mi_resource_props, sizeof (mac_resource_props_t));
403 
404 	if (mip->mi_minor <= MAC_MAX_MINOR) {
405 		/* Create a style-2 DLPI device */
406 		if (ddi_create_minor_node(mip->mi_dip, driver, S_IFCHR, 0,
407 		    DDI_NT_NET, CLONE_DEV) != DDI_SUCCESS)
408 			goto fail;
409 		style2_created = B_TRUE;
410 
411 		/* Create a style-1 DLPI device */
412 		if (ddi_create_minor_node(mip->mi_dip, mip->mi_name, S_IFCHR,
413 		    mip->mi_minor, DDI_NT_NET, 0) != DDI_SUCCESS)
414 			goto fail;
415 		style1_created = B_TRUE;
416 	}
417 
418 	mac_flow_l2tab_create(mip, &mip->mi_flow_tab);
419 
420 	rw_enter(&i_mac_impl_lock, RW_WRITER);
421 	if (mod_hash_insert(i_mac_impl_hash,
422 	    (mod_hash_key_t)mip->mi_name, (mod_hash_val_t)mip) != 0) {
423 		rw_exit(&i_mac_impl_lock);
424 		err = EEXIST;
425 		goto fail;
426 	}
427 
428 	DTRACE_PROBE2(mac__register, struct devnames *, dnp,
429 	    (mac_impl_t *), mip);
430 
431 	/*
432 	 * Mark the MAC to be ready for open.
433 	 */
434 	mip->mi_state_flags &= ~MIS_DISABLED;
435 	rw_exit(&i_mac_impl_lock);
436 
437 	atomic_inc_32(&i_mac_impl_count);
438 
439 	cmn_err(CE_NOTE, "!%s registered", mip->mi_name);
440 	*mhp = (mac_handle_t)mip;
441 	return (0);
442 
443 fail:
444 	if (style1_created)
445 		ddi_remove_minor_node(mip->mi_dip, mip->mi_name);
446 
447 	if (style2_created)
448 		ddi_remove_minor_node(mip->mi_dip, driver);
449 
450 	mac_addr_factory_fini(mip);
451 
452 	/* Clean up registered MAC addresses */
453 	mac_fini_macaddr(mip);
454 
455 	/* Clean up registered rings */
456 	mac_free_rings(mip, MAC_RING_TYPE_RX);
457 	mac_free_rings(mip, MAC_RING_TYPE_TX);
458 
459 	/* Clean up notification thread */
460 	if (mip->mi_notify_thread != NULL)
461 		i_mac_notify_exit(mip);
462 
463 	if (mip->mi_info.mi_unicst_addr != NULL) {
464 		kmem_free(mip->mi_info.mi_unicst_addr,
465 		    mip->mi_type->mt_addr_length);
466 		mip->mi_info.mi_unicst_addr = NULL;
467 	}
468 
469 	mac_stat_destroy(mip);
470 
471 	if (mip->mi_type != NULL) {
472 		atomic_dec_32(&mip->mi_type->mt_ref);
473 		mip->mi_type = NULL;
474 	}
475 
476 	if (mip->mi_pdata != NULL) {
477 		kmem_free(mip->mi_pdata, mip->mi_pdata_size);
478 		mip->mi_pdata = NULL;
479 		mip->mi_pdata_size = 0;
480 	}
481 
482 	if (minor != 0) {
483 		ASSERT(minor > MAC_MAX_MINOR);
484 		mac_minor_rele(minor);
485 	}
486 
487 	mac_unregister_priv_prop(mip);
488 
489 	kmem_cache_free(i_mac_impl_cachep, mip);
490 	return (err);
491 }
492 
493 /*
494  * Unregister from the GLDv3 framework
495  */
496 int
497 mac_unregister(mac_handle_t mh)
498 {
499 	int			err;
500 	mac_impl_t		*mip = (mac_impl_t *)mh;
501 	mod_hash_val_t		val;
502 	mac_margin_req_t	*mmr, *nextmmr;
503 
504 	/* Fail the unregister if there are any open references to this mac. */
505 	if ((err = mac_disable_nowait(mh)) != 0)
506 		return (err);
507 
508 	/*
509 	 * Clean up notification thread and wait for it to exit.
510 	 */
511 	i_mac_notify_exit(mip);
512 
513 	i_mac_perim_enter(mip);
514 
515 	/*
516 	 * There is still resource properties configured over this mac.
517 	 */
518 	if (mip->mi_resource_props.mrp_mask != 0)
519 		mac_fastpath_enable((mac_handle_t)mip);
520 
521 	if (mip->mi_minor < MAC_MAX_MINOR + 1) {
522 		ddi_remove_minor_node(mip->mi_dip, mip->mi_name);
523 		ddi_remove_minor_node(mip->mi_dip,
524 		    (char *)ddi_driver_name(mip->mi_dip));
525 	}
526 
527 	ASSERT(mip->mi_nactiveclients == 0 && !(mip->mi_state_flags &
528 	    MIS_EXCLUSIVE));
529 
530 	mac_stat_destroy(mip);
531 
532 	(void) mod_hash_remove(i_mac_impl_hash,
533 	    (mod_hash_key_t)mip->mi_name, &val);
534 	ASSERT(mip == (mac_impl_t *)val);
535 
536 	ASSERT(i_mac_impl_count > 0);
537 	atomic_dec_32(&i_mac_impl_count);
538 
539 	if (mip->mi_pdata != NULL)
540 		kmem_free(mip->mi_pdata, mip->mi_pdata_size);
541 	mip->mi_pdata = NULL;
542 	mip->mi_pdata_size = 0;
543 
544 	/*
545 	 * Free the list of margin request.
546 	 */
547 	for (mmr = mip->mi_mmrp; mmr != NULL; mmr = nextmmr) {
548 		nextmmr = mmr->mmr_nextp;
549 		kmem_free(mmr, sizeof (mac_margin_req_t));
550 	}
551 	mip->mi_mmrp = NULL;
552 
553 	mip->mi_linkstate = mip->mi_lowlinkstate = LINK_STATE_UNKNOWN;
554 	kmem_free(mip->mi_info.mi_unicst_addr, mip->mi_type->mt_addr_length);
555 	mip->mi_info.mi_unicst_addr = NULL;
556 
557 	atomic_dec_32(&mip->mi_type->mt_ref);
558 	mip->mi_type = NULL;
559 
560 	/*
561 	 * Free the primary MAC address.
562 	 */
563 	mac_fini_macaddr(mip);
564 
565 	/*
566 	 * free all rings
567 	 */
568 	mac_free_rings(mip, MAC_RING_TYPE_RX);
569 	mac_free_rings(mip, MAC_RING_TYPE_TX);
570 
571 	mac_addr_factory_fini(mip);
572 
573 	bzero(mip->mi_addr, MAXMACADDRLEN);
574 	bzero(mip->mi_dstaddr, MAXMACADDRLEN);
575 
576 	/* and the flows */
577 	mac_flow_tab_destroy(mip->mi_flow_tab);
578 	mip->mi_flow_tab = NULL;
579 
580 	if (mip->mi_minor > MAC_MAX_MINOR)
581 		mac_minor_rele(mip->mi_minor);
582 
583 	cmn_err(CE_NOTE, "!%s unregistered", mip->mi_name);
584 
585 	/*
586 	 * Reset the perim related fields to default values before
587 	 * kmem_cache_free
588 	 */
589 	i_mac_perim_exit(mip);
590 	mip->mi_state_flags = 0;
591 
592 	mac_unregister_priv_prop(mip);
593 
594 	ASSERT(mip->mi_bridge_link == NULL);
595 	kmem_cache_free(i_mac_impl_cachep, mip);
596 
597 	return (0);
598 }
599 
600 /* DATA RECEPTION */
601 
602 /*
603  * This function is invoked for packets received by the MAC driver in
604  * interrupt context. The ring generation number provided by the driver
605  * is matched with the ring generation number held in MAC. If they do not
606  * match, received packets are considered stale packets coming from an older
607  * assignment of the ring. Drop them.
608  */
609 void
610 mac_rx_ring(mac_handle_t mh, mac_ring_handle_t mrh, mblk_t *mp_chain,
611     uint64_t mr_gen_num)
612 {
613 	mac_ring_t		*mr = (mac_ring_t *)mrh;
614 
615 	if ((mr != NULL) && (mr->mr_gen_num != mr_gen_num)) {
616 		DTRACE_PROBE2(mac__rx__rings__stale__packet, uint64_t,
617 		    mr->mr_gen_num, uint64_t, mr_gen_num);
618 		freemsgchain(mp_chain);
619 		return;
620 	}
621 	mac_rx(mh, (mac_resource_handle_t)mrh, mp_chain);
622 }
623 
624 /*
625  * This function is invoked for each packet received by the underlying driver.
626  */
627 void
628 mac_rx(mac_handle_t mh, mac_resource_handle_t mrh, mblk_t *mp_chain)
629 {
630 	mac_impl_t *mip = (mac_impl_t *)mh;
631 
632 	/*
633 	 * Check if the link is part of a bridge.  If not, then we don't need
634 	 * to take the lock to remain consistent.  Make this common case
635 	 * lock-free and tail-call optimized.
636 	 */
637 	if (mip->mi_bridge_link == NULL) {
638 		mac_rx_common(mh, mrh, mp_chain);
639 	} else {
640 		/*
641 		 * Once we take a reference on the bridge link, the bridge
642 		 * module itself can't unload, so the callback pointers are
643 		 * stable.
644 		 */
645 		mutex_enter(&mip->mi_bridge_lock);
646 		if ((mh = mip->mi_bridge_link) != NULL)
647 			mac_bridge_ref_cb(mh, B_TRUE);
648 		mutex_exit(&mip->mi_bridge_lock);
649 		if (mh == NULL) {
650 			mac_rx_common((mac_handle_t)mip, mrh, mp_chain);
651 		} else {
652 			mac_bridge_rx_cb(mh, mrh, mp_chain);
653 			mac_bridge_ref_cb(mh, B_FALSE);
654 		}
655 	}
656 }
657 
658 /*
659  * Special case function: this allows snooping of packets transmitted and
660  * received by TRILL. By design, they go directly into the TRILL module.
661  */
662 void
663 mac_trill_snoop(mac_handle_t mh, mblk_t *mp)
664 {
665 	mac_impl_t *mip = (mac_impl_t *)mh;
666 
667 	if (mip->mi_promisc_list != NULL)
668 		mac_promisc_dispatch(mip, mp, NULL);
669 }
670 
671 /*
672  * This is the upward reentry point for packets arriving from the bridging
673  * module and from mac_rx for links not part of a bridge.
674  */
675 void
676 mac_rx_common(mac_handle_t mh, mac_resource_handle_t mrh, mblk_t *mp_chain)
677 {
678 	mac_impl_t		*mip = (mac_impl_t *)mh;
679 	mac_ring_t		*mr = (mac_ring_t *)mrh;
680 	mac_soft_ring_set_t 	*mac_srs;
681 	mblk_t			*bp = mp_chain;
682 	boolean_t		hw_classified = B_FALSE;
683 
684 	/*
685 	 * If there are any promiscuous mode callbacks defined for
686 	 * this MAC, pass them a copy if appropriate.
687 	 */
688 	if (mip->mi_promisc_list != NULL)
689 		mac_promisc_dispatch(mip, mp_chain, NULL);
690 
691 	if (mr != NULL) {
692 		/*
693 		 * If the SRS teardown has started, just return. The 'mr'
694 		 * continues to be valid until the driver unregisters the mac.
695 		 * Hardware classified packets will not make their way up
696 		 * beyond this point once the teardown has started. The driver
697 		 * is never passed a pointer to a flow entry or SRS or any
698 		 * structure that can be freed much before mac_unregister.
699 		 */
700 		mutex_enter(&mr->mr_lock);
701 		if ((mr->mr_state != MR_INUSE) || (mr->mr_flag &
702 		    (MR_INCIPIENT | MR_CONDEMNED | MR_QUIESCE))) {
703 			mutex_exit(&mr->mr_lock);
704 			freemsgchain(mp_chain);
705 			return;
706 		}
707 		if (mr->mr_classify_type == MAC_HW_CLASSIFIER) {
708 			hw_classified = B_TRUE;
709 			MR_REFHOLD_LOCKED(mr);
710 		}
711 		mutex_exit(&mr->mr_lock);
712 
713 		/*
714 		 * We check if an SRS is controlling this ring.
715 		 * If so, we can directly call the srs_lower_proc
716 		 * routine otherwise we need to go through mac_rx_classify
717 		 * to reach the right place.
718 		 */
719 		if (hw_classified) {
720 			mac_srs = mr->mr_srs;
721 			/*
722 			 * This is supposed to be the fast path.
723 			 * All packets received though here were steered by
724 			 * the hardware classifier, and share the same
725 			 * MAC header info.
726 			 */
727 			mac_srs->srs_rx.sr_lower_proc(mh,
728 			    (mac_resource_handle_t)mac_srs, mp_chain, B_FALSE);
729 			MR_REFRELE(mr);
730 			return;
731 		}
732 		/* We'll fall through to software classification */
733 	} else {
734 		flow_entry_t *flent;
735 		int err;
736 
737 		rw_enter(&mip->mi_rw_lock, RW_READER);
738 		if (mip->mi_single_active_client != NULL) {
739 			flent = mip->mi_single_active_client->mci_flent_list;
740 			FLOW_TRY_REFHOLD(flent, err);
741 			rw_exit(&mip->mi_rw_lock);
742 			if (err == 0) {
743 				(flent->fe_cb_fn)(flent->fe_cb_arg1,
744 				    flent->fe_cb_arg2, mp_chain, B_FALSE);
745 				FLOW_REFRELE(flent);
746 				return;
747 			}
748 		} else {
749 			rw_exit(&mip->mi_rw_lock);
750 		}
751 	}
752 
753 	if (!FLOW_TAB_EMPTY(mip->mi_flow_tab)) {
754 		if ((bp = mac_rx_flow(mh, mrh, bp)) == NULL)
755 			return;
756 	}
757 
758 	freemsgchain(bp);
759 }
760 
761 /* DATA TRANSMISSION */
762 
763 /*
764  * A driver's notification to resume transmission, in case of a provider
765  * without TX rings.
766  */
767 void
768 mac_tx_update(mac_handle_t mh)
769 {
770 	/*
771 	 * Walk the list of MAC clients (mac_client_handle)
772 	 * and update
773 	 */
774 	i_mac_tx_srs_notify((mac_impl_t *)mh, NULL);
775 }
776 
777 /*
778  * A driver's notification to resume transmission on the specified TX ring.
779  */
780 void
781 mac_tx_ring_update(mac_handle_t mh, mac_ring_handle_t rh)
782 {
783 	i_mac_tx_srs_notify((mac_impl_t *)mh, rh);
784 }
785 
786 /* LINK STATE */
787 /*
788  * Notify the MAC layer about a link state change
789  */
790 void
791 mac_link_update(mac_handle_t mh, link_state_t link)
792 {
793 	mac_impl_t	*mip = (mac_impl_t *)mh;
794 
795 	/*
796 	 * Save the link state.
797 	 */
798 	mip->mi_lowlinkstate = link;
799 
800 	/*
801 	 * Send a MAC_NOTE_LOWLINK notification.  This tells the notification
802 	 * thread to deliver both lower and upper notifications.
803 	 */
804 	i_mac_notify(mip, MAC_NOTE_LOWLINK);
805 }
806 
807 /*
808  * Notify the MAC layer about a link state change due to bridging.
809  */
810 void
811 mac_link_redo(mac_handle_t mh, link_state_t link)
812 {
813 	mac_impl_t	*mip = (mac_impl_t *)mh;
814 
815 	/*
816 	 * Save the link state.
817 	 */
818 	mip->mi_linkstate = link;
819 
820 	/*
821 	 * Send a MAC_NOTE_LINK notification.  Only upper notifications are
822 	 * made.
823 	 */
824 	i_mac_notify(mip, MAC_NOTE_LINK);
825 }
826 
827 /* MINOR NODE HANDLING */
828 
829 /*
830  * Given a dev_t, return the instance number (PPA) associated with it.
831  * Drivers can use this in their getinfo(9e) implementation to lookup
832  * the instance number (i.e. PPA) of the device, to use as an index to
833  * their own array of soft state structures.
834  *
835  * Returns -1 on error.
836  */
837 int
838 mac_devt_to_instance(dev_t devt)
839 {
840 	return (dld_devt_to_instance(devt));
841 }
842 
843 /*
844  * This function returns the first minor number that is available for
845  * driver private use.  All minor numbers smaller than this are
846  * reserved for GLDv3 use.
847  */
848 minor_t
849 mac_private_minor(void)
850 {
851 	return (MAC_PRIVATE_MINOR);
852 }
853 
854 /* OTHER CONTROL INFORMATION */
855 
856 /*
857  * A driver notified us that its primary MAC address has changed.
858  */
859 void
860 mac_unicst_update(mac_handle_t mh, const uint8_t *addr)
861 {
862 	mac_impl_t	*mip = (mac_impl_t *)mh;
863 
864 	if (mip->mi_type->mt_addr_length == 0)
865 		return;
866 
867 	i_mac_perim_enter(mip);
868 	/*
869 	 * If address doesn't change, do nothing.
870 	 */
871 	if (bcmp(addr, mip->mi_addr, mip->mi_type->mt_addr_length) == 0) {
872 		i_mac_perim_exit(mip);
873 		return;
874 	}
875 
876 	/*
877 	 * Freshen the MAC address value and update all MAC clients that
878 	 * share this MAC address.
879 	 */
880 	mac_freshen_macaddr(mac_find_macaddr(mip, mip->mi_addr),
881 	    (uint8_t *)addr);
882 
883 	i_mac_perim_exit(mip);
884 
885 	/*
886 	 * Send a MAC_NOTE_UNICST notification.
887 	 */
888 	i_mac_notify(mip, MAC_NOTE_UNICST);
889 }
890 
891 void
892 mac_dst_update(mac_handle_t mh, const uint8_t *addr)
893 {
894 	mac_impl_t	*mip = (mac_impl_t *)mh;
895 
896 	if (mip->mi_type->mt_addr_length == 0)
897 		return;
898 
899 	i_mac_perim_enter(mip);
900 	bcopy(addr, mip->mi_dstaddr, mip->mi_type->mt_addr_length);
901 	i_mac_perim_exit(mip);
902 	i_mac_notify(mip, MAC_NOTE_DEST);
903 }
904 
905 /*
906  * MAC plugin information changed.
907  */
908 int
909 mac_pdata_update(mac_handle_t mh, void *mac_pdata, size_t dsize)
910 {
911 	mac_impl_t	*mip = (mac_impl_t *)mh;
912 
913 	/*
914 	 * Verify that the plugin supports MAC plugin data and that the
915 	 * supplied data is valid.
916 	 */
917 	if (!(mip->mi_type->mt_ops.mtops_ops & MTOPS_PDATA_VERIFY))
918 		return (EINVAL);
919 	if (!mip->mi_type->mt_ops.mtops_pdata_verify(mac_pdata, dsize))
920 		return (EINVAL);
921 
922 	if (mip->mi_pdata != NULL)
923 		kmem_free(mip->mi_pdata, mip->mi_pdata_size);
924 
925 	mip->mi_pdata = kmem_alloc(dsize, KM_SLEEP);
926 	bcopy(mac_pdata, mip->mi_pdata, dsize);
927 	mip->mi_pdata_size = dsize;
928 
929 	/*
930 	 * Since the MAC plugin data is used to construct MAC headers that
931 	 * were cached in fast-path headers, we need to flush fast-path
932 	 * information for links associated with this mac.
933 	 */
934 	i_mac_notify(mip, MAC_NOTE_FASTPATH_FLUSH);
935 	return (0);
936 }
937 
938 /*
939  * Invoked by driver as well as the framework to notify its capability change.
940  */
941 void
942 mac_capab_update(mac_handle_t mh)
943 {
944 	/* Send MAC_NOTE_CAPAB_CHG notification */
945 	i_mac_notify((mac_impl_t *)mh, MAC_NOTE_CAPAB_CHG);
946 }
947 
948 int
949 mac_maxsdu_update(mac_handle_t mh, uint_t sdu_max)
950 {
951 	mac_impl_t	*mip = (mac_impl_t *)mh;
952 
953 	if (sdu_max == 0 || sdu_max < mip->mi_sdu_min)
954 		return (EINVAL);
955 	mip->mi_sdu_max = sdu_max;
956 
957 	/* Send a MAC_NOTE_SDU_SIZE notification. */
958 	i_mac_notify(mip, MAC_NOTE_SDU_SIZE);
959 	return (0);
960 }
961 
962 /* PRIVATE FUNCTIONS, FOR INTERNAL USE ONLY */
963 
964 /*
965  * Updates the mac_impl structure with the current state of the link
966  */
967 static void
968 i_mac_log_link_state(mac_impl_t *mip)
969 {
970 	/*
971 	 * If no change, then it is not interesting.
972 	 */
973 	if (mip->mi_lastlowlinkstate == mip->mi_lowlinkstate)
974 		return;
975 
976 	switch (mip->mi_lowlinkstate) {
977 	case LINK_STATE_UP:
978 		if (mip->mi_type->mt_ops.mtops_ops & MTOPS_LINK_DETAILS) {
979 			char det[200];
980 
981 			mip->mi_type->mt_ops.mtops_link_details(det,
982 			    sizeof (det), (mac_handle_t)mip, mip->mi_pdata);
983 
984 			cmn_err(CE_NOTE, "!%s link up, %s", mip->mi_name, det);
985 		} else {
986 			cmn_err(CE_NOTE, "!%s link up", mip->mi_name);
987 		}
988 		break;
989 
990 	case LINK_STATE_DOWN:
991 		/*
992 		 * Only transitions from UP to DOWN are interesting
993 		 */
994 		if (mip->mi_lastlowlinkstate != LINK_STATE_UNKNOWN)
995 			cmn_err(CE_NOTE, "!%s link down", mip->mi_name);
996 		break;
997 
998 	case LINK_STATE_UNKNOWN:
999 		/*
1000 		 * This case is normally not interesting.
1001 		 */
1002 		break;
1003 	}
1004 	mip->mi_lastlowlinkstate = mip->mi_lowlinkstate;
1005 }
1006 
1007 /*
1008  * Main routine for the callbacks notifications thread
1009  */
1010 static void
1011 i_mac_notify_thread(void *arg)
1012 {
1013 	mac_impl_t	*mip = arg;
1014 	callb_cpr_t	cprinfo;
1015 	mac_cb_t	*mcb;
1016 	mac_cb_info_t	*mcbi;
1017 	mac_notify_cb_t	*mncb;
1018 
1019 	mcbi = &mip->mi_notify_cb_info;
1020 	CALLB_CPR_INIT(&cprinfo, mcbi->mcbi_lockp, callb_generic_cpr,
1021 	    "i_mac_notify_thread");
1022 
1023 	mutex_enter(mcbi->mcbi_lockp);
1024 
1025 	for (;;) {
1026 		uint32_t	bits;
1027 		uint32_t	type;
1028 
1029 		bits = mip->mi_notify_bits;
1030 		if (bits == 0) {
1031 			CALLB_CPR_SAFE_BEGIN(&cprinfo);
1032 			cv_wait(&mcbi->mcbi_cv, mcbi->mcbi_lockp);
1033 			CALLB_CPR_SAFE_END(&cprinfo, mcbi->mcbi_lockp);
1034 			continue;
1035 		}
1036 		mip->mi_notify_bits = 0;
1037 		if ((bits & (1 << MAC_NNOTE)) != 0) {
1038 			/* request to quit */
1039 			ASSERT(mip->mi_state_flags & MIS_DISABLED);
1040 			break;
1041 		}
1042 
1043 		mutex_exit(mcbi->mcbi_lockp);
1044 
1045 		/*
1046 		 * Log link changes on the actual link, but then do reports on
1047 		 * synthetic state (if part of a bridge).
1048 		 */
1049 		if ((bits & (1 << MAC_NOTE_LOWLINK)) != 0) {
1050 			link_state_t newstate;
1051 			mac_handle_t mh;
1052 
1053 			i_mac_log_link_state(mip);
1054 			newstate = mip->mi_lowlinkstate;
1055 			if (mip->mi_bridge_link != NULL) {
1056 				mutex_enter(&mip->mi_bridge_lock);
1057 				if ((mh = mip->mi_bridge_link) != NULL) {
1058 					newstate = mac_bridge_ls_cb(mh,
1059 					    newstate);
1060 				}
1061 				mutex_exit(&mip->mi_bridge_lock);
1062 			}
1063 			if (newstate != mip->mi_linkstate) {
1064 				mip->mi_linkstate = newstate;
1065 				bits |= 1 << MAC_NOTE_LINK;
1066 			}
1067 		}
1068 
1069 		/*
1070 		 * Do notification callbacks for each notification type.
1071 		 */
1072 		for (type = 0; type < MAC_NNOTE; type++) {
1073 			if ((bits & (1 << type)) == 0) {
1074 				continue;
1075 			}
1076 
1077 			if (mac_notify_cb_list[type] != NULL)
1078 				(*mac_notify_cb_list[type])(mip);
1079 
1080 			/*
1081 			 * Walk the list of notifications.
1082 			 */
1083 			MAC_CALLBACK_WALKER_INC(&mip->mi_notify_cb_info);
1084 			for (mcb = mip->mi_notify_cb_list; mcb != NULL;
1085 			    mcb = mcb->mcb_nextp) {
1086 				mncb = (mac_notify_cb_t *)mcb->mcb_objp;
1087 				mncb->mncb_fn(mncb->mncb_arg, type);
1088 			}
1089 			MAC_CALLBACK_WALKER_DCR(&mip->mi_notify_cb_info,
1090 			    &mip->mi_notify_cb_list);
1091 		}
1092 
1093 		mutex_enter(mcbi->mcbi_lockp);
1094 	}
1095 
1096 	mip->mi_state_flags |= MIS_NOTIFY_DONE;
1097 	cv_broadcast(&mcbi->mcbi_cv);
1098 
1099 	/* CALLB_CPR_EXIT drops the lock */
1100 	CALLB_CPR_EXIT(&cprinfo);
1101 	thread_exit();
1102 }
1103 
1104 /*
1105  * Signal the i_mac_notify_thread asking it to quit.
1106  * Then wait till it is done.
1107  */
1108 void
1109 i_mac_notify_exit(mac_impl_t *mip)
1110 {
1111 	mac_cb_info_t	*mcbi;
1112 
1113 	mcbi = &mip->mi_notify_cb_info;
1114 
1115 	mutex_enter(mcbi->mcbi_lockp);
1116 	mip->mi_notify_bits = (1 << MAC_NNOTE);
1117 	cv_broadcast(&mcbi->mcbi_cv);
1118 
1119 
1120 	while ((mip->mi_notify_thread != NULL) &&
1121 	    !(mip->mi_state_flags & MIS_NOTIFY_DONE)) {
1122 		cv_wait(&mcbi->mcbi_cv, mcbi->mcbi_lockp);
1123 	}
1124 
1125 	/* Necessary clean up before doing kmem_cache_free */
1126 	mip->mi_state_flags &= ~MIS_NOTIFY_DONE;
1127 	mip->mi_notify_bits = 0;
1128 	mip->mi_notify_thread = NULL;
1129 	mutex_exit(mcbi->mcbi_lockp);
1130 }
1131 
1132 /*
1133  * Entry point invoked by drivers to dynamically add a ring to an
1134  * existing group.
1135  */
1136 int
1137 mac_group_add_ring(mac_group_handle_t gh, int index)
1138 {
1139 	mac_group_t *group = (mac_group_t *)gh;
1140 	mac_impl_t *mip = (mac_impl_t *)group->mrg_mh;
1141 	int ret;
1142 
1143 	i_mac_perim_enter(mip);
1144 
1145 	/*
1146 	 * Only RX rings can be added or removed by drivers currently.
1147 	 */
1148 	ASSERT(group->mrg_type == MAC_RING_TYPE_RX);
1149 
1150 	ret = i_mac_group_add_ring(group, NULL, index);
1151 
1152 	i_mac_perim_exit(mip);
1153 
1154 	return (ret);
1155 }
1156 
1157 /*
1158  * Entry point invoked by drivers to dynamically remove a ring
1159  * from an existing group. The specified ring handle must no longer
1160  * be used by the driver after a call to this function.
1161  */
1162 void
1163 mac_group_rem_ring(mac_group_handle_t gh, mac_ring_handle_t rh)
1164 {
1165 	mac_group_t *group = (mac_group_t *)gh;
1166 	mac_impl_t *mip = (mac_impl_t *)group->mrg_mh;
1167 
1168 	i_mac_perim_enter(mip);
1169 
1170 	/*
1171 	 * Only RX rings can be added or removed by drivers currently.
1172 	 */
1173 	ASSERT(group->mrg_type == MAC_RING_TYPE_RX);
1174 
1175 	i_mac_group_rem_ring(group, (mac_ring_t *)rh, B_TRUE);
1176 
1177 	i_mac_perim_exit(mip);
1178 }
1179