xref: /illumos-gate/usr/src/uts/common/io/dld/dld_str.c (revision cc6c5292fa8a241fe50604cf6a918edfbf7cd7d2)
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, Version 1.0 only
6  * (the "License").  You may not use this file except in compliance
7  * with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or http://www.opensolaris.org/os/licensing.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your own identifying
18  * information: Portions Copyright [yyyy] [name of copyright owner]
19  *
20  * CDDL HEADER END
21  */
22 /*
23  * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 #pragma ident	"%Z%%M%	%I%	%E% SMI"
28 
29 /*
30  * Data-Link Driver
31  */
32 
33 #include	<sys/stropts.h>
34 #include	<sys/strsun.h>
35 #include	<sys/strsubr.h>
36 #include	<sys/atomic.h>
37 #include	<sys/mkdev.h>
38 #include	<sys/vlan.h>
39 #include	<sys/dld.h>
40 #include	<sys/dld_impl.h>
41 #include	<sys/dls_impl.h>
42 #include	<inet/common.h>
43 
44 static int	str_constructor(void *, void *, int);
45 static void	str_destructor(void *, void *);
46 static mblk_t	*str_unitdata_ind(dld_str_t *, mblk_t *);
47 static void	str_notify_promisc_on_phys(dld_str_t *);
48 static void	str_notify_promisc_off_phys(dld_str_t *);
49 static void	str_notify_phys_addr(dld_str_t *, const uint8_t *);
50 static void	str_notify_link_up(dld_str_t *);
51 static void	str_notify_link_down(dld_str_t *);
52 static void	str_notify_capab_reneg(dld_str_t *);
53 static void	str_notify_speed(dld_str_t *, uint32_t);
54 static void	str_notify(void *, mac_notify_type_t);
55 
56 static void	ioc_raw(dld_str_t *, mblk_t *);
57 static void	ioc_fast(dld_str_t *,  mblk_t *);
58 static void	ioc(dld_str_t *, mblk_t *);
59 static void	dld_ioc(dld_str_t *, mblk_t *);
60 static minor_t	dld_minor_hold(boolean_t);
61 static void	dld_minor_rele(minor_t);
62 
63 static uint32_t		str_count;
64 static kmem_cache_t	*str_cachep;
65 static vmem_t		*minor_arenap;
66 static uint32_t		minor_count;
67 
68 #define	MINOR_TO_PTR(minor)	((void *)(uintptr_t)(minor))
69 #define	PTR_TO_MINOR(ptr)	((minor_t)(uintptr_t)(ptr))
70 
71 /*
72  * Some notes on entry points, flow-control, queueing and locking:
73  *
74  * This driver exports the traditional STREAMS put entry point as well as
75  * the non-STREAMS fast-path transmit routine which is provided to IP via
76  * the DL_CAPAB_POLL negotiation.  The put procedure handles all control
77  * and data operations, while the fast-path routine deals only with M_DATA
78  * fast-path packets.  Regardless of the entry point, all outbound packets
79  * will end up in str_mdata_fastpath_put(), where they will be delivered to
80  * the MAC driver.
81  *
82  * The transmit logic operates in two modes: a "not busy" mode where the
83  * packets will be delivered to the MAC for a send attempt, or "busy" mode
84  * where they will be enqueued in the internal queue because of flow-control.
85  * Flow-control happens when the MAC driver indicates the packets couldn't
86  * be transmitted due to lack of resources (e.g. running out of descriptors).
87  * In such case, the driver will place a dummy message on its write-side
88  * STREAMS queue so that the queue is marked as "full".  Any subsequent
89  * packets arriving at the driver will be enqueued in the internal queue,
90  * which is drained in the context of the service thread that gets scheduled
91  * whenever the driver is in the "busy" mode.  When all packets have been
92  * successfully delivered by MAC and the internal queue is empty, it will
93  * transition to the "not busy" mode by removing the dummy message from the
94  * write-side STREAMS queue; in effect this will trigger backenabling.
95  * The sizes of q_hiwat and q_lowat are set to 1 and 0, respectively, due
96  * to the above reasons.
97  *
98  * The driver implements an internal transmit queue independent of STREAMS.
99  * This allows for flexibility and provides a fast enqueue/dequeue mechanism
100  * compared to the putq() and get() STREAMS interfaces.  The only putq() and
101  * getq() operations done by the driver are those related to placing and
102  * removing the dummy message to/from the write-side STREAMS queue for flow-
103  * control purposes.
104  *
105  * Locking is done independent of STREAMS due to the driver being fully MT.
106  * Threads entering the driver (either from put or service entry points)
107  * will most likely be readers, with the exception of a few writer cases
108  * such those handling DLPI attach/detach/bind/unbind/etc. or any of the
109  * DLD-related ioctl requests.  The DLPI detach case is special, because
110  * it involves freeing resources and therefore must be single-threaded.
111  * Unfortunately the readers/writers lock can't be used to protect against
112  * it, because the lock is dropped prior to the driver calling places where
113  * putnext() may be invoked, and such places may depend on those resources
114  * to exist.  Because of this, the driver always completes the DLPI detach
115  * process when there are no other threads running in the driver.  This is
116  * done by keeping track of the number of threads, such that the the last
117  * thread leaving the driver will finish the pending DLPI detach operation.
118  */
119 
120 /*
121  * dld_max_q_count is the queue depth threshold used to limit the number of
122  * outstanding packets or bytes allowed in the queue; once this limit is
123  * reached the driver will free any incoming ones until the queue depth
124  * drops below the threshold.
125  *
126  * This buffering is provided to accomodate clients which do not employ
127  * their own buffering scheme, and to handle occasional packet bursts.
128  * Clients which handle their own buffering will receive positive feedback
129  * from this driver as soon as it transitions into the "busy" state, i.e.
130  * when the queue is initially filled up; they will get backenabled once
131  * the queue is empty.
132  *
133  * The value chosen here is rather arbitrary; in future some intelligent
134  * heuristics may be involved which could take into account the hardware's
135  * transmit ring size, etc.
136  */
137 uint_t dld_max_q_count = (16 * 1024 *1024);
138 
139 static dev_info_t *
140 dld_finddevinfo(dev_t dev)
141 {
142 	minor_t		minor = getminor(dev);
143 	char		*drvname = ddi_major_to_name(getmajor(dev));
144 	char		name[MAXNAMELEN];
145 	dls_vlan_t	*dvp = NULL;
146 	dev_info_t	*dip = NULL;
147 
148 	if (drvname == NULL || minor == 0 || minor > DLD_MAX_PPA + 1)
149 		return (NULL);
150 
151 	(void) snprintf(name, MAXNAMELEN, "%s%d", drvname, (int)minor - 1);
152 	if (dls_vlan_hold(name, &dvp, B_FALSE) != 0)
153 		return (NULL);
154 
155 	dip = mac_devinfo_get(dvp->dv_dlp->dl_mh);
156 	dls_vlan_rele(dvp);
157 	return (dip);
158 }
159 
160 /*
161  * devo_getinfo: getinfo(9e)
162  */
163 /*ARGSUSED*/
164 int
165 dld_getinfo(dev_info_t *dip, ddi_info_cmd_t cmd, void *arg, void **resp)
166 {
167 	dev_info_t	*devinfo;
168 	minor_t		minor = getminor((dev_t)arg);
169 	int		rc = DDI_FAILURE;
170 
171 	switch (cmd) {
172 	case DDI_INFO_DEVT2DEVINFO:
173 		if ((devinfo = dld_finddevinfo((dev_t)arg)) != NULL) {
174 			*(dev_info_t **)resp = devinfo;
175 			rc = DDI_SUCCESS;
176 		}
177 		break;
178 	case DDI_INFO_DEVT2INSTANCE:
179 		if (minor > 0 && minor <= DLD_MAX_PPA + 1) {
180 			*(int *)resp = (int)minor - 1;
181 			rc = DDI_SUCCESS;
182 		}
183 		break;
184 	}
185 	return (rc);
186 }
187 
188 /*
189  * qi_qopen: open(9e)
190  */
191 /*ARGSUSED*/
192 int
193 dld_open(queue_t *rq, dev_t *devp, int flag, int sflag, cred_t *credp)
194 {
195 	dld_str_t	*dsp;
196 	major_t		major;
197 	minor_t		minor;
198 	int		err;
199 
200 	if (sflag == MODOPEN)
201 		return (ENOTSUP);
202 
203 	/*
204 	 * This is a cloning driver and therefore each queue should only
205 	 * ever get opened once.
206 	 */
207 	if (rq->q_ptr != NULL)
208 		return (EBUSY);
209 
210 	major = getmajor(*devp);
211 	minor = getminor(*devp);
212 	if (minor > DLD_MAX_MINOR)
213 		return (ENODEV);
214 
215 	/*
216 	 * Create a new dld_str_t for the stream. This will grab a new minor
217 	 * number that will be handed back in the cloned dev_t.  Creation may
218 	 * fail if we can't allocate the dummy mblk used for flow-control.
219 	 */
220 	dsp = dld_str_create(rq, DLD_DLPI, major,
221 	    ((minor == 0) ? DL_STYLE2 : DL_STYLE1));
222 	if (dsp == NULL)
223 		return (ENOSR);
224 
225 	ASSERT(dsp->ds_dlstate == DL_UNATTACHED);
226 	if (minor != 0) {
227 		/*
228 		 * Style 1 open
229 		 */
230 
231 		if ((err = dld_str_attach(dsp, (t_uscalar_t)minor - 1)) != 0)
232 			goto failed;
233 		ASSERT(dsp->ds_dlstate == DL_UNBOUND);
234 	} else {
235 		(void) qassociate(rq, -1);
236 	}
237 
238 	/*
239 	 * Enable the queue srv(9e) routine.
240 	 */
241 	qprocson(rq);
242 
243 	/*
244 	 * Construct a cloned dev_t to hand back.
245 	 */
246 	*devp = makedevice(getmajor(*devp), dsp->ds_minor);
247 	return (0);
248 
249 failed:
250 	dld_str_destroy(dsp);
251 	return (err);
252 }
253 
254 /*
255  * qi_qclose: close(9e)
256  */
257 int
258 dld_close(queue_t *rq)
259 {
260 	dld_str_t	*dsp = rq->q_ptr;
261 
262 	/*
263 	 * Disable the queue srv(9e) routine.
264 	 */
265 	qprocsoff(rq);
266 
267 	/*
268 	 * At this point we can not be entered by any threads via STREAMS
269 	 * or the direct call interface, which is available only to IP.
270 	 * After the interface is unplumbed, IP wouldn't have any reference
271 	 * to this instance, and therefore we are now effectively single
272 	 * threaded and don't require any lock protection.  Flush all
273 	 * pending packets which are sitting in the transmit queue.
274 	 */
275 	ASSERT(dsp->ds_thr == 0);
276 	dld_tx_flush(dsp);
277 
278 	/*
279 	 * This stream was open to a provider node. Check to see
280 	 * if it has been cleanly shut down.
281 	 */
282 	if (dsp->ds_dlstate != DL_UNATTACHED) {
283 		/*
284 		 * The stream is either open to a style 1 provider or
285 		 * this is not clean shutdown. Detach from the PPA.
286 		 * (This is still ok even in the style 1 case).
287 		 */
288 		dld_str_detach(dsp);
289 	}
290 
291 	dld_str_destroy(dsp);
292 	return (0);
293 }
294 
295 /*
296  * qi_qputp: put(9e)
297  */
298 void
299 dld_wput(queue_t *wq, mblk_t *mp)
300 {
301 	dld_str_t *dsp = (dld_str_t *)wq->q_ptr;
302 
303 	DLD_ENTER(dsp);
304 
305 	switch (DB_TYPE(mp)) {
306 	case M_DATA:
307 		rw_enter(&dsp->ds_lock, RW_READER);
308 		if (dsp->ds_dlstate != DL_IDLE ||
309 		    dsp->ds_mode == DLD_UNITDATA) {
310 			freemsg(mp);
311 		} else if (dsp->ds_mode == DLD_FASTPATH) {
312 			str_mdata_fastpath_put(dsp, mp);
313 		} else if (dsp->ds_mode == DLD_RAW) {
314 			str_mdata_raw_put(dsp, mp);
315 		}
316 		rw_exit(&dsp->ds_lock);
317 		break;
318 	case M_PROTO:
319 	case M_PCPROTO:
320 		dld_proto(dsp, mp);
321 		break;
322 	case M_IOCTL:
323 		dld_ioc(dsp, mp);
324 		break;
325 	case M_FLUSH:
326 		if (*mp->b_rptr & FLUSHW) {
327 			dld_tx_flush(dsp);
328 			*mp->b_rptr &= ~FLUSHW;
329 		}
330 
331 		if (*mp->b_rptr & FLUSHR) {
332 			qreply(wq, mp);
333 		} else {
334 			freemsg(mp);
335 		}
336 		break;
337 	default:
338 		freemsg(mp);
339 		break;
340 	}
341 
342 	DLD_EXIT(dsp);
343 }
344 
345 /*
346  * qi_srvp: srv(9e)
347  */
348 void
349 dld_wsrv(queue_t *wq)
350 {
351 	mblk_t		*mp;
352 	dld_str_t	*dsp = wq->q_ptr;
353 
354 	DLD_ENTER(dsp);
355 	rw_enter(&dsp->ds_lock, RW_READER);
356 	/*
357 	 * Grab all packets (chained via b_next) off our transmit queue
358 	 * and try to send them all to the MAC layer.  Since the queue
359 	 * is independent of streams, we are able to dequeue all messages
360 	 * at once without looping through getq() and manually chaining
361 	 * them.  Note that the queue size parameters (byte and message
362 	 * counts) are cleared as well, but we postpone the backenabling
363 	 * until after the MAC transmit since some packets may end up
364 	 * back at our transmit queue.
365 	 */
366 	mutex_enter(&dsp->ds_tx_list_lock);
367 	if ((mp = dsp->ds_tx_list_head) == NULL) {
368 		ASSERT(!dsp->ds_tx_qbusy);
369 		ASSERT(dsp->ds_tx_flow_mp != NULL);
370 		ASSERT(dsp->ds_tx_list_head == NULL);
371 		ASSERT(dsp->ds_tx_list_tail == NULL);
372 		ASSERT(dsp->ds_tx_cnt == 0);
373 		ASSERT(dsp->ds_tx_msgcnt == 0);
374 		mutex_exit(&dsp->ds_tx_list_lock);
375 		goto done;
376 	}
377 	dsp->ds_tx_list_head = dsp->ds_tx_list_tail = NULL;
378 	dsp->ds_tx_cnt = dsp->ds_tx_msgcnt = 0;
379 	mutex_exit(&dsp->ds_tx_list_lock);
380 
381 	/*
382 	 * Discard packets unless we are attached and bound; note that
383 	 * the driver mode (fastpath/raw/unitdata) is irrelevant here,
384 	 * because regardless of the mode all transmit will end up in
385 	 * str_mdata_fastpath_put() where the packets may be queued.
386 	 */
387 	ASSERT(DB_TYPE(mp) == M_DATA);
388 	if (dsp->ds_dlstate != DL_IDLE) {
389 		freemsgchain(mp);
390 		goto done;
391 	}
392 
393 	/*
394 	 * Attempt to transmit one or more packets.  If the MAC can't
395 	 * send them all, re-queue the packet(s) at the beginning of
396 	 * the transmit queue to avoid any re-ordering.
397 	 */
398 	if ((mp = dls_tx(dsp->ds_dc, mp)) != NULL)
399 		dld_tx_enqueue(dsp, mp, B_TRUE);
400 
401 	/*
402 	 * Grab the list lock again and check if the transmit queue is
403 	 * really empty; if so, lift up flow-control and backenable any
404 	 * writer queues.  If the queue is not empty, schedule service
405 	 * thread to drain it.
406 	 */
407 	mutex_enter(&dsp->ds_tx_list_lock);
408 	if (dsp->ds_tx_list_head == NULL) {
409 		dsp->ds_tx_flow_mp = getq(wq);
410 		ASSERT(dsp->ds_tx_flow_mp != NULL);
411 		dsp->ds_tx_qbusy = B_FALSE;
412 	}
413 	mutex_exit(&dsp->ds_tx_list_lock);
414 done:
415 	rw_exit(&dsp->ds_lock);
416 	DLD_EXIT(dsp);
417 }
418 
419 void
420 dld_init_ops(struct dev_ops *ops, const char *name)
421 {
422 	struct streamtab *stream;
423 	struct qinit *rq, *wq;
424 	struct module_info *modinfo;
425 
426 	modinfo = kmem_zalloc(sizeof (struct module_info), KM_SLEEP);
427 	modinfo->mi_idname = kmem_zalloc(FMNAMESZ, KM_SLEEP);
428 	(void) snprintf(modinfo->mi_idname, FMNAMESZ, "%s", name);
429 	modinfo->mi_minpsz = 0;
430 	modinfo->mi_maxpsz = 64*1024;
431 	modinfo->mi_hiwat  = 1;
432 	modinfo->mi_lowat = 0;
433 
434 	rq = kmem_zalloc(sizeof (struct qinit), KM_SLEEP);
435 	rq->qi_qopen = dld_open;
436 	rq->qi_qclose = dld_close;
437 	rq->qi_minfo = modinfo;
438 
439 	wq = kmem_zalloc(sizeof (struct qinit), KM_SLEEP);
440 	wq->qi_putp = (pfi_t)dld_wput;
441 	wq->qi_srvp = (pfi_t)dld_wsrv;
442 	wq->qi_minfo = modinfo;
443 
444 	stream = kmem_zalloc(sizeof (struct streamtab), KM_SLEEP);
445 	stream->st_rdinit = rq;
446 	stream->st_wrinit = wq;
447 	ops->devo_cb_ops->cb_str = stream;
448 
449 	ops->devo_getinfo = &dld_getinfo;
450 }
451 
452 void
453 dld_fini_ops(struct dev_ops *ops)
454 {
455 	struct streamtab *stream;
456 	struct qinit *rq, *wq;
457 	struct module_info *modinfo;
458 
459 	stream = ops->devo_cb_ops->cb_str;
460 	rq = stream->st_rdinit;
461 	wq = stream->st_wrinit;
462 	modinfo = rq->qi_minfo;
463 	ASSERT(wq->qi_minfo == modinfo);
464 
465 	kmem_free(stream, sizeof (struct streamtab));
466 	kmem_free(wq, sizeof (struct qinit));
467 	kmem_free(rq, sizeof (struct qinit));
468 	kmem_free(modinfo->mi_idname, FMNAMESZ);
469 	kmem_free(modinfo, sizeof (struct module_info));
470 }
471 
472 /*
473  * Initialize this module's data structures.
474  */
475 void
476 dld_str_init(void)
477 {
478 	/*
479 	 * Create dld_str_t object cache.
480 	 */
481 	str_cachep = kmem_cache_create("dld_str_cache", sizeof (dld_str_t),
482 	    0, str_constructor, str_destructor, NULL, NULL, NULL, 0);
483 	ASSERT(str_cachep != NULL);
484 
485 	/*
486 	 * Allocate a vmem arena to manage minor numbers. The range of the
487 	 * arena will be from DLD_MAX_MINOR + 1 to MAXMIN (maximum legal
488 	 * minor number).
489 	 */
490 	minor_arenap = vmem_create("dld_minor_arena",
491 	    MINOR_TO_PTR(DLD_MAX_MINOR + 1), MAXMIN, 1, NULL, NULL, NULL, 0,
492 	    VM_SLEEP | VMC_IDENTIFIER);
493 	ASSERT(minor_arenap != NULL);
494 }
495 
496 /*
497  * Tear down this module's data structures.
498  */
499 int
500 dld_str_fini(void)
501 {
502 	/*
503 	 * Make sure that there are no objects in use.
504 	 */
505 	if (str_count != 0)
506 		return (EBUSY);
507 
508 	/*
509 	 * Check to see if there are any minor numbers still in use.
510 	 */
511 	if (minor_count != 0)
512 		return (EBUSY);
513 
514 	/*
515 	 * Destroy object cache.
516 	 */
517 	kmem_cache_destroy(str_cachep);
518 	vmem_destroy(minor_arenap);
519 	return (0);
520 }
521 
522 /*
523  * Create a new dld_str_t object.
524  */
525 dld_str_t *
526 dld_str_create(queue_t *rq, uint_t type, major_t major, t_uscalar_t style)
527 {
528 	dld_str_t	*dsp;
529 
530 	/*
531 	 * Allocate an object from the cache.
532 	 */
533 	atomic_add_32(&str_count, 1);
534 	dsp = kmem_cache_alloc(str_cachep, KM_SLEEP);
535 
536 	/*
537 	 * Allocate the dummy mblk for flow-control.
538 	 */
539 	dsp->ds_tx_flow_mp = allocb(1, BPRI_HI);
540 	if (dsp->ds_tx_flow_mp == NULL) {
541 		kmem_cache_free(str_cachep, dsp);
542 		atomic_add_32(&str_count, -1);
543 		return (NULL);
544 	}
545 	dsp->ds_type = type;
546 	dsp->ds_major = major;
547 	dsp->ds_style = style;
548 
549 	/*
550 	 * Initialize the queue pointers.
551 	 */
552 	ASSERT(RD(rq) == rq);
553 	dsp->ds_rq = rq;
554 	dsp->ds_wq = WR(rq);
555 	rq->q_ptr = WR(rq)->q_ptr = (void *)dsp;
556 
557 	/*
558 	 * We want explicit control over our write-side STREAMS queue
559 	 * where the dummy mblk gets added/removed for flow-control.
560 	 */
561 	noenable(WR(rq));
562 
563 	return (dsp);
564 }
565 
566 /*
567  * Destroy a dld_str_t object.
568  */
569 void
570 dld_str_destroy(dld_str_t *dsp)
571 {
572 	queue_t		*rq;
573 	queue_t		*wq;
574 
575 	/*
576 	 * Clear the queue pointers.
577 	 */
578 	rq = dsp->ds_rq;
579 	wq = dsp->ds_wq;
580 	ASSERT(wq == WR(rq));
581 
582 	rq->q_ptr = wq->q_ptr = NULL;
583 	dsp->ds_rq = dsp->ds_wq = NULL;
584 
585 	ASSERT(!RW_LOCK_HELD(&dsp->ds_lock));
586 	ASSERT(MUTEX_NOT_HELD(&dsp->ds_tx_list_lock));
587 	ASSERT(dsp->ds_tx_list_head == NULL);
588 	ASSERT(dsp->ds_tx_list_tail == NULL);
589 	ASSERT(dsp->ds_tx_cnt == 0);
590 	ASSERT(dsp->ds_tx_msgcnt == 0);
591 	ASSERT(!dsp->ds_tx_qbusy);
592 
593 	ASSERT(MUTEX_NOT_HELD(&dsp->ds_thr_lock));
594 	ASSERT(dsp->ds_thr == 0);
595 	ASSERT(dsp->ds_detach_req == NULL);
596 
597 	/*
598 	 * Reinitialize all the flags.
599 	 */
600 	dsp->ds_notifications = 0;
601 	dsp->ds_passivestate = DLD_UNINITIALIZED;
602 	dsp->ds_mode = DLD_UNITDATA;
603 
604 	/*
605 	 * Free the dummy mblk if exists.
606 	 */
607 	if (dsp->ds_tx_flow_mp != NULL) {
608 		freeb(dsp->ds_tx_flow_mp);
609 		dsp->ds_tx_flow_mp = NULL;
610 	}
611 	/*
612 	 * Free the object back to the cache.
613 	 */
614 	kmem_cache_free(str_cachep, dsp);
615 	atomic_add_32(&str_count, -1);
616 }
617 
618 /*
619  * kmem_cache contructor function: see kmem_cache_create(9f).
620  */
621 /*ARGSUSED*/
622 static int
623 str_constructor(void *buf, void *cdrarg, int kmflags)
624 {
625 	dld_str_t	*dsp = buf;
626 
627 	bzero(buf, sizeof (dld_str_t));
628 
629 	/*
630 	 * Allocate a new minor number.
631 	 */
632 	if ((dsp->ds_minor = dld_minor_hold(kmflags == KM_SLEEP)) == 0)
633 		return (-1);
634 
635 	/*
636 	 * Initialize the DLPI state machine.
637 	 */
638 	dsp->ds_dlstate = DL_UNATTACHED;
639 
640 	mutex_init(&dsp->ds_thr_lock, NULL, MUTEX_DRIVER, NULL);
641 	rw_init(&dsp->ds_lock, NULL, RW_DRIVER, NULL);
642 	mutex_init(&dsp->ds_tx_list_lock, NULL, MUTEX_DRIVER, NULL);
643 
644 	return (0);
645 }
646 
647 /*
648  * kmem_cache destructor function.
649  */
650 /*ARGSUSED*/
651 static void
652 str_destructor(void *buf, void *cdrarg)
653 {
654 	dld_str_t	*dsp = buf;
655 
656 	/*
657 	 * Make sure the DLPI state machine was reset.
658 	 */
659 	ASSERT(dsp->ds_dlstate == DL_UNATTACHED);
660 
661 	/*
662 	 * Make sure the data-link interface was closed.
663 	 */
664 	ASSERT(dsp->ds_mh == NULL);
665 	ASSERT(dsp->ds_dc == NULL);
666 
667 	/*
668 	 * Make sure enabled notifications are cleared.
669 	 */
670 	ASSERT(dsp->ds_notifications == 0);
671 
672 	/*
673 	 * Make sure polling is disabled.
674 	 */
675 	ASSERT(!dsp->ds_polling);
676 
677 	/*
678 	 * Release the minor number.
679 	 */
680 	dld_minor_rele(dsp->ds_minor);
681 
682 	ASSERT(!RW_LOCK_HELD(&dsp->ds_lock));
683 	rw_destroy(&dsp->ds_lock);
684 
685 	ASSERT(MUTEX_NOT_HELD(&dsp->ds_tx_list_lock));
686 	mutex_destroy(&dsp->ds_tx_list_lock);
687 	ASSERT(dsp->ds_tx_flow_mp == NULL);
688 
689 	ASSERT(MUTEX_NOT_HELD(&dsp->ds_thr_lock));
690 	mutex_destroy(&dsp->ds_thr_lock);
691 	ASSERT(dsp->ds_detach_req == NULL);
692 }
693 
694 /*
695  * M_DATA put (IP fast-path mode)
696  */
697 void
698 str_mdata_fastpath_put(dld_str_t *dsp, mblk_t *mp)
699 {
700 	/*
701 	 * This function can be called from within dld or from an upper
702 	 * layer protocol (currently only tcp). If we are in the busy
703 	 * mode enqueue the packet(s) and return.  Otherwise hand them
704 	 * over to the MAC driver for transmission; any remaining one(s)
705 	 * which didn't get sent will be queued.
706 	 *
707 	 * Note here that we don't grab the list lock prior to checking
708 	 * the busy flag.  This is okay, because a missed transition
709 	 * will not cause any packet reordering for any particular TCP
710 	 * connection (which is single-threaded).  The enqueue routine
711 	 * will atomically set the busy flag and schedule the service
712 	 * thread to run; the flag is only cleared by the service thread
713 	 * when there is no more packet to be transmitted.
714 	 */
715 	if (dsp->ds_tx_qbusy || (mp = dls_tx(dsp->ds_dc, mp)) != NULL)
716 		dld_tx_enqueue(dsp, mp, B_FALSE);
717 }
718 
719 /*
720  * M_DATA put (raw mode)
721  */
722 void
723 str_mdata_raw_put(dld_str_t *dsp, mblk_t *mp)
724 {
725 	struct ether_header	*ehp;
726 	mblk_t			*bp;
727 	size_t			size;
728 	size_t			hdrlen;
729 
730 	size = MBLKL(mp);
731 	if (size < sizeof (struct ether_header))
732 		goto discard;
733 
734 	hdrlen = sizeof (struct ether_header);
735 
736 	ehp = (struct ether_header *)mp->b_rptr;
737 	if (ntohs(ehp->ether_type) == VLAN_TPID) {
738 		struct ether_vlan_header	*evhp;
739 
740 		if (size < sizeof (struct ether_vlan_header))
741 			goto discard;
742 
743 		/*
744 		 * Replace vtag with our own
745 		 */
746 		evhp = (struct ether_vlan_header *)ehp;
747 		evhp->ether_tci = htons(VLAN_TCI(dsp->ds_pri,
748 		    ETHER_CFI, dsp->ds_vid));
749 		hdrlen = sizeof (struct ether_vlan_header);
750 	}
751 
752 	/*
753 	 * Check the packet is not too big and that any remaining
754 	 * fragment list is composed entirely of M_DATA messages. (We
755 	 * know the first fragment was M_DATA otherwise we could not
756 	 * have got here).
757 	 */
758 	for (bp = mp->b_cont; bp != NULL; bp = bp->b_cont) {
759 		if (DB_TYPE(bp) != M_DATA)
760 			goto discard;
761 		size += MBLKL(bp);
762 	}
763 
764 	if (size > dsp->ds_mip->mi_sdu_max + hdrlen)
765 		goto discard;
766 
767 	str_mdata_fastpath_put(dsp, mp);
768 	return;
769 
770 discard:
771 	freemsg(mp);
772 }
773 
774 /*
775  * Process DL_ATTACH_REQ (style 2) or open(2) (style 1).
776  */
777 int
778 dld_str_attach(dld_str_t *dsp, t_uscalar_t ppa)
779 {
780 	int			err;
781 	const char		*drvname;
782 	char			name[MAXNAMELEN];
783 	dls_channel_t		dc;
784 	uint_t			addr_length;
785 
786 	ASSERT(dsp->ds_dc == NULL);
787 
788 	if ((drvname = ddi_major_to_name(dsp->ds_major)) == NULL)
789 		return (EINVAL);
790 
791 	(void) snprintf(name, MAXNAMELEN, "%s%u", drvname, ppa);
792 
793 	if (strcmp(drvname, "aggr") != 0 &&
794 	    qassociate(dsp->ds_wq, DLS_PPA2INST(ppa)) != 0)
795 		return (EINVAL);
796 
797 	/*
798 	 * Open a channel.
799 	 */
800 	if ((err = dls_open(name, &dc)) != 0) {
801 		(void) qassociate(dsp->ds_wq, -1);
802 		return (err);
803 	}
804 
805 	/*
806 	 * Cache the MAC interface handle, a pointer to the immutable MAC
807 	 * information and the current and 'factory' MAC address.
808 	 */
809 	dsp->ds_mh = dls_mac(dc);
810 	dsp->ds_mip = mac_info(dsp->ds_mh);
811 
812 	mac_unicst_get(dsp->ds_mh, dsp->ds_curr_addr);
813 
814 	addr_length = dsp->ds_mip->mi_addr_length;
815 	bcopy(dsp->ds_mip->mi_unicst_addr, dsp->ds_fact_addr, addr_length);
816 
817 	/*
818 	 * Cache the interface VLAN identifier. (This will be VLAN_ID_NONE for
819 	 * a non-VLAN interface).
820 	 */
821 	dsp->ds_vid = dls_vid(dc);
822 
823 	/*
824 	 * Set the default packet priority.
825 	 */
826 	dsp->ds_pri = 0;
827 
828 	/*
829 	 * Add a notify function so that the we get updates from the MAC.
830 	 */
831 	dsp->ds_mnh = mac_notify_add(dsp->ds_mh, str_notify, (void *)dsp);
832 
833 	dsp->ds_dc = dc;
834 	dsp->ds_dlstate = DL_UNBOUND;
835 
836 	return (0);
837 }
838 
839 /*
840  * Process DL_DETACH_REQ (style 2) or close(2) (style 1). Can also be called
841  * from close(2) for style 2.
842  */
843 void
844 dld_str_detach(dld_str_t *dsp)
845 {
846 	ASSERT(dsp->ds_thr == 0);
847 
848 	/*
849 	 * Remove the notify function.
850 	 */
851 	mac_notify_remove(dsp->ds_mh, dsp->ds_mnh);
852 
853 	/*
854 	 * Re-initialize the DLPI state machine.
855 	 */
856 	dsp->ds_dlstate = DL_UNATTACHED;
857 
858 	/*
859 	 * Clear the polling and promisc flags.
860 	 */
861 	dsp->ds_polling = B_FALSE;
862 	dsp->ds_promisc = 0;
863 
864 	/*
865 	 * Close the channel.
866 	 */
867 	dls_close(dsp->ds_dc);
868 	dsp->ds_dc = NULL;
869 	dsp->ds_mh = NULL;
870 
871 	(void) qassociate(dsp->ds_wq, -1);
872 }
873 
874 /*
875  * Raw mode receive function.
876  */
877 /*ARGSUSED*/
878 void
879 dld_str_rx_raw(void *arg, mac_resource_handle_t mrh, mblk_t *mp,
880     size_t header_length)
881 {
882 	dld_str_t		*dsp = (dld_str_t *)arg;
883 	mblk_t			*next;
884 
885 	ASSERT(mp != NULL);
886 	do {
887 		/*
888 		 * Get the pointer to the next packet in the chain and then
889 		 * clear b_next before the packet gets passed on.
890 		 */
891 		next = mp->b_next;
892 		mp->b_next = NULL;
893 
894 		/*
895 		 * Wind back b_rptr to point at the MAC header.
896 		 */
897 		ASSERT(mp->b_rptr >= DB_BASE(mp) + header_length);
898 		mp->b_rptr -= header_length;
899 		if (header_length == sizeof (struct ether_vlan_header)) {
900 			/*
901 			 * Strip off the vtag
902 			 */
903 			ovbcopy(mp->b_rptr, mp->b_rptr + VLAN_TAGSZ,
904 			    2 * ETHERADDRL);
905 			mp->b_rptr += VLAN_TAGSZ;
906 		}
907 
908 		/*
909 		 * Pass the packet on.
910 		 */
911 		putnext(dsp->ds_rq, mp);
912 
913 		/*
914 		 * Move on to the next packet in the chain.
915 		 */
916 		mp = next;
917 	} while (mp != NULL);
918 }
919 
920 /*
921  * Fast-path receive function.
922  */
923 /*ARGSUSED*/
924 void
925 dld_str_rx_fastpath(void *arg, mac_resource_handle_t mrh, mblk_t *mp,
926     size_t header_length)
927 {
928 	dld_str_t		*dsp = (dld_str_t *)arg;
929 	mblk_t			*next;
930 
931 	ASSERT(mp != NULL);
932 	do {
933 		/*
934 		 * Get the pointer to the next packet in the chain and then
935 		 * clear b_next before the packet gets passed on.
936 		 */
937 		next = mp->b_next;
938 		mp->b_next = NULL;
939 
940 		/*
941 		 * Pass the packet on.
942 		 */
943 		putnext(dsp->ds_rq, mp);
944 
945 		/*
946 		 * Move on to the next packet in the chain.
947 		 */
948 		mp = next;
949 	} while (mp != NULL);
950 }
951 
952 /*
953  * Default receive function (send DL_UNITDATA_IND messages).
954  */
955 /*ARGSUSED*/
956 void
957 dld_str_rx_unitdata(void *arg, mac_resource_handle_t mrh, mblk_t *mp,
958     size_t header_length)
959 {
960 	dld_str_t		*dsp = (dld_str_t *)arg;
961 	mblk_t			*ud_mp;
962 	mblk_t			*next;
963 
964 	ASSERT(mp != NULL);
965 	do {
966 		/*
967 		 * Get the pointer to the next packet in the chain and then
968 		 * clear b_next before the packet gets passed on.
969 		 */
970 		next = mp->b_next;
971 		mp->b_next = NULL;
972 
973 		/*
974 		 * Wind back b_rptr to point at the MAC header.
975 		 */
976 		ASSERT(mp->b_rptr >= DB_BASE(mp) + header_length);
977 		mp->b_rptr -= header_length;
978 
979 		/*
980 		 * Create the DL_UNITDATA_IND M_PROTO.
981 		 */
982 		if ((ud_mp = str_unitdata_ind(dsp, mp)) == NULL) {
983 			freemsgchain(mp);
984 			return;
985 		}
986 
987 		/*
988 		 * Advance b_rptr to point at the payload again.
989 		 */
990 		mp->b_rptr += header_length;
991 
992 		/*
993 		 * Prepend the DL_UNITDATA_IND.
994 		 */
995 		ud_mp->b_cont = mp;
996 
997 		/*
998 		 * Send the message.
999 		 */
1000 		putnext(dsp->ds_rq, ud_mp);
1001 
1002 		/*
1003 		 * Move on to the next packet in the chain.
1004 		 */
1005 		mp = next;
1006 	} while (mp != NULL);
1007 }
1008 
1009 /*
1010  * Generate DL_NOTIFY_IND messages to notify the DLPI consumer of the
1011  * current state of the interface.
1012  */
1013 void
1014 dld_str_notify_ind(dld_str_t *dsp)
1015 {
1016 	mac_notify_type_t	type;
1017 
1018 	for (type = 0; type < MAC_NNOTE; type++)
1019 		str_notify(dsp, type);
1020 }
1021 
1022 typedef struct dl_unitdata_ind_wrapper {
1023 	dl_unitdata_ind_t	dl_unitdata;
1024 	uint8_t			dl_dest_addr[MAXADDRLEN + sizeof (uint16_t)];
1025 	uint8_t			dl_src_addr[MAXADDRLEN + sizeof (uint16_t)];
1026 } dl_unitdata_ind_wrapper_t;
1027 
1028 /*
1029  * Create a DL_UNITDATA_IND M_PROTO message.
1030  */
1031 static mblk_t *
1032 str_unitdata_ind(dld_str_t *dsp, mblk_t *mp)
1033 {
1034 	mblk_t				*nmp;
1035 	dl_unitdata_ind_wrapper_t	*dlwp;
1036 	dl_unitdata_ind_t		*dlp;
1037 	dls_header_info_t		dhi;
1038 	uint_t				addr_length;
1039 	uint8_t				*daddr;
1040 	uint8_t				*saddr;
1041 
1042 	/*
1043 	 * Get the packet header information.
1044 	 */
1045 	dls_header_info(dsp->ds_dc, mp, &dhi);
1046 
1047 	/*
1048 	 * Allocate a message large enough to contain the wrapper structure
1049 	 * defined above.
1050 	 */
1051 	if ((nmp = mexchange(dsp->ds_wq, NULL,
1052 	    sizeof (dl_unitdata_ind_wrapper_t), M_PROTO,
1053 	    DL_UNITDATA_IND)) == NULL)
1054 		return (NULL);
1055 
1056 	dlwp = (dl_unitdata_ind_wrapper_t *)nmp->b_rptr;
1057 
1058 	dlp = &(dlwp->dl_unitdata);
1059 	ASSERT(dlp == (dl_unitdata_ind_t *)nmp->b_rptr);
1060 	ASSERT(dlp->dl_primitive == DL_UNITDATA_IND);
1061 
1062 	/*
1063 	 * Copy in the destination address.
1064 	 */
1065 	addr_length = dsp->ds_mip->mi_addr_length;
1066 	daddr = dlwp->dl_dest_addr;
1067 	dlp->dl_dest_addr_offset = (uintptr_t)daddr - (uintptr_t)dlp;
1068 	bcopy(dhi.dhi_daddr, daddr, addr_length);
1069 
1070 	/*
1071 	 * Set the destination DLSAP to our bound DLSAP value.
1072 	 */
1073 	*(uint16_t *)(daddr + addr_length) = dsp->ds_sap;
1074 	dlp->dl_dest_addr_length = addr_length + sizeof (uint16_t);
1075 
1076 	/*
1077 	 * If the destination address was a group address then
1078 	 * dl_group_address field should be non-zero.
1079 	 */
1080 	dlp->dl_group_address = dhi.dhi_isgroup;
1081 
1082 	/*
1083 	 * Copy in the source address.
1084 	 */
1085 	saddr = dlwp->dl_src_addr;
1086 	dlp->dl_src_addr_offset = (uintptr_t)saddr - (uintptr_t)dlp;
1087 	bcopy(dhi.dhi_saddr, saddr, addr_length);
1088 
1089 	/*
1090 	 * Set the source DLSAP to the packet ethertype.
1091 	 */
1092 	*(uint16_t *)(saddr + addr_length) = dhi.dhi_ethertype;
1093 	dlp->dl_src_addr_length = addr_length + sizeof (uint16_t);
1094 
1095 	return (nmp);
1096 }
1097 
1098 /*
1099  * DL_NOTIFY_IND: DL_NOTE_PROMISC_ON_PHYS
1100  */
1101 static void
1102 str_notify_promisc_on_phys(dld_str_t *dsp)
1103 {
1104 	mblk_t		*mp;
1105 	dl_notify_ind_t	*dlip;
1106 
1107 	if (!(dsp->ds_notifications & DL_NOTE_PROMISC_ON_PHYS))
1108 		return;
1109 
1110 	if ((mp = mexchange(dsp->ds_wq, NULL, sizeof (dl_notify_ind_t),
1111 	    M_PROTO, 0)) == NULL)
1112 		return;
1113 
1114 	bzero(mp->b_rptr, sizeof (dl_notify_ind_t));
1115 	dlip = (dl_notify_ind_t *)mp->b_rptr;
1116 	dlip->dl_primitive = DL_NOTIFY_IND;
1117 	dlip->dl_notification = DL_NOTE_PROMISC_ON_PHYS;
1118 
1119 	qreply(dsp->ds_wq, mp);
1120 }
1121 
1122 /*
1123  * DL_NOTIFY_IND: DL_NOTE_PROMISC_OFF_PHYS
1124  */
1125 static void
1126 str_notify_promisc_off_phys(dld_str_t *dsp)
1127 {
1128 	mblk_t		*mp;
1129 	dl_notify_ind_t	*dlip;
1130 
1131 	if (!(dsp->ds_notifications & DL_NOTE_PROMISC_OFF_PHYS))
1132 		return;
1133 
1134 	if ((mp = mexchange(dsp->ds_wq, NULL, sizeof (dl_notify_ind_t),
1135 	    M_PROTO, 0)) == NULL)
1136 		return;
1137 
1138 	bzero(mp->b_rptr, sizeof (dl_notify_ind_t));
1139 	dlip = (dl_notify_ind_t *)mp->b_rptr;
1140 	dlip->dl_primitive = DL_NOTIFY_IND;
1141 	dlip->dl_notification = DL_NOTE_PROMISC_OFF_PHYS;
1142 
1143 	qreply(dsp->ds_wq, mp);
1144 }
1145 
1146 /*
1147  * DL_NOTIFY_IND: DL_NOTE_PHYS_ADDR
1148  */
1149 static void
1150 str_notify_phys_addr(dld_str_t *dsp, const uint8_t *addr)
1151 {
1152 	mblk_t		*mp;
1153 	dl_notify_ind_t	*dlip;
1154 	uint_t		addr_length;
1155 	uint16_t	ethertype;
1156 
1157 	if (!(dsp->ds_notifications & DL_NOTE_PHYS_ADDR))
1158 		return;
1159 
1160 	addr_length = dsp->ds_mip->mi_addr_length;
1161 	if ((mp = mexchange(dsp->ds_wq, NULL,
1162 	    sizeof (dl_notify_ind_t) + addr_length + sizeof (uint16_t),
1163 	    M_PROTO, 0)) == NULL)
1164 		return;
1165 
1166 	bzero(mp->b_rptr, sizeof (dl_notify_ind_t));
1167 	dlip = (dl_notify_ind_t *)mp->b_rptr;
1168 	dlip->dl_primitive = DL_NOTIFY_IND;
1169 	dlip->dl_notification = DL_NOTE_PHYS_ADDR;
1170 	dlip->dl_data = DL_CURR_PHYS_ADDR;
1171 	dlip->dl_addr_offset = sizeof (dl_notify_ind_t);
1172 	dlip->dl_addr_length = addr_length + sizeof (uint16_t);
1173 
1174 	bcopy(addr, &dlip[1], addr_length);
1175 
1176 	ethertype = (dsp->ds_sap < ETHERTYPE_802_MIN) ? 0 : dsp->ds_sap;
1177 	*(uint16_t *)((uchar_t *)(dlip + 1) + addr_length) =
1178 		ethertype;
1179 
1180 	qreply(dsp->ds_wq, mp);
1181 }
1182 
1183 /*
1184  * DL_NOTIFY_IND: DL_NOTE_LINK_UP
1185  */
1186 static void
1187 str_notify_link_up(dld_str_t *dsp)
1188 {
1189 	mblk_t		*mp;
1190 	dl_notify_ind_t	*dlip;
1191 
1192 	if (!(dsp->ds_notifications & DL_NOTE_LINK_UP))
1193 		return;
1194 
1195 	if ((mp = mexchange(dsp->ds_wq, NULL, sizeof (dl_notify_ind_t),
1196 	    M_PROTO, 0)) == NULL)
1197 		return;
1198 
1199 	bzero(mp->b_rptr, sizeof (dl_notify_ind_t));
1200 	dlip = (dl_notify_ind_t *)mp->b_rptr;
1201 	dlip->dl_primitive = DL_NOTIFY_IND;
1202 	dlip->dl_notification = DL_NOTE_LINK_UP;
1203 
1204 	qreply(dsp->ds_wq, mp);
1205 }
1206 
1207 /*
1208  * DL_NOTIFY_IND: DL_NOTE_LINK_DOWN
1209  */
1210 static void
1211 str_notify_link_down(dld_str_t *dsp)
1212 {
1213 	mblk_t		*mp;
1214 	dl_notify_ind_t	*dlip;
1215 
1216 	if (!(dsp->ds_notifications & DL_NOTE_LINK_DOWN))
1217 		return;
1218 
1219 	if ((mp = mexchange(dsp->ds_wq, NULL, sizeof (dl_notify_ind_t),
1220 	    M_PROTO, 0)) == NULL)
1221 		return;
1222 
1223 	bzero(mp->b_rptr, sizeof (dl_notify_ind_t));
1224 	dlip = (dl_notify_ind_t *)mp->b_rptr;
1225 	dlip->dl_primitive = DL_NOTIFY_IND;
1226 	dlip->dl_notification = DL_NOTE_LINK_DOWN;
1227 
1228 	qreply(dsp->ds_wq, mp);
1229 }
1230 
1231 /*
1232  * DL_NOTIFY_IND: DL_NOTE_SPEED
1233  */
1234 static void
1235 str_notify_speed(dld_str_t *dsp, uint32_t speed)
1236 {
1237 	mblk_t		*mp;
1238 	dl_notify_ind_t	*dlip;
1239 
1240 	if (!(dsp->ds_notifications & DL_NOTE_SPEED))
1241 		return;
1242 
1243 	if ((mp = mexchange(dsp->ds_wq, NULL, sizeof (dl_notify_ind_t),
1244 	    M_PROTO, 0)) == NULL)
1245 		return;
1246 
1247 	bzero(mp->b_rptr, sizeof (dl_notify_ind_t));
1248 	dlip = (dl_notify_ind_t *)mp->b_rptr;
1249 	dlip->dl_primitive = DL_NOTIFY_IND;
1250 	dlip->dl_notification = DL_NOTE_SPEED;
1251 	dlip->dl_data = speed;
1252 
1253 	qreply(dsp->ds_wq, mp);
1254 }
1255 
1256 /*
1257  * DL_NOTIFY_IND: DL_NOTE_CAPAB_RENEG
1258  */
1259 static void
1260 str_notify_capab_reneg(dld_str_t *dsp)
1261 {
1262 	mblk_t		*mp;
1263 	dl_notify_ind_t	*dlip;
1264 
1265 	if (!(dsp->ds_notifications & DL_NOTE_CAPAB_RENEG))
1266 		return;
1267 
1268 	if ((mp = mexchange(dsp->ds_wq, NULL, sizeof (dl_notify_ind_t),
1269 	    M_PROTO, 0)) == NULL)
1270 		return;
1271 
1272 	bzero(mp->b_rptr, sizeof (dl_notify_ind_t));
1273 	dlip = (dl_notify_ind_t *)mp->b_rptr;
1274 	dlip->dl_primitive = DL_NOTIFY_IND;
1275 	dlip->dl_notification = DL_NOTE_CAPAB_RENEG;
1276 
1277 	qreply(dsp->ds_wq, mp);
1278 }
1279 
1280 /*
1281  * MAC notification callback.
1282  */
1283 static void
1284 str_notify(void *arg, mac_notify_type_t type)
1285 {
1286 	dld_str_t		*dsp = (dld_str_t *)arg;
1287 	queue_t			*q = dsp->ds_wq;
1288 
1289 	switch (type) {
1290 	case MAC_NOTE_TX:
1291 		qenable(q);
1292 		break;
1293 
1294 	case MAC_NOTE_DEVPROMISC:
1295 		/*
1296 		 * Send the appropriate DL_NOTIFY_IND.
1297 		 */
1298 		if (mac_promisc_get(dsp->ds_mh, MAC_DEVPROMISC))
1299 			str_notify_promisc_on_phys(dsp);
1300 		else
1301 			str_notify_promisc_off_phys(dsp);
1302 		break;
1303 
1304 	case MAC_NOTE_PROMISC:
1305 		break;
1306 
1307 	case MAC_NOTE_UNICST:
1308 		/*
1309 		 * This notification is sent whenever the MAC unicast address
1310 		 * changes. We need to re-cache the address.
1311 		 */
1312 		mac_unicst_get(dsp->ds_mh, dsp->ds_curr_addr);
1313 
1314 		/*
1315 		 * Send the appropriate DL_NOTIFY_IND.
1316 		 */
1317 		str_notify_phys_addr(dsp, dsp->ds_curr_addr);
1318 		break;
1319 
1320 	case MAC_NOTE_LINK:
1321 		/*
1322 		 * This notification is sent every time the MAC driver
1323 		 * updates the link state.
1324 		 */
1325 		switch (mac_link_get(dsp->ds_mh)) {
1326 		case LINK_STATE_UP:
1327 			/*
1328 			 * The link is up so send the appropriate
1329 			 * DL_NOTIFY_IND.
1330 			 */
1331 			str_notify_link_up(dsp);
1332 
1333 			/*
1334 			 * If we can find the link speed then send a
1335 			 * DL_NOTIFY_IND for that too.
1336 			 */
1337 			if (dsp->ds_mip->mi_stat[MAC_STAT_IFSPEED]) {
1338 				uint64_t	val;
1339 
1340 				val = mac_stat_get(dsp->ds_mh,
1341 				    MAC_STAT_IFSPEED);
1342 				str_notify_speed(dsp,
1343 				    (uint32_t)(val / 1000ull));
1344 			}
1345 			break;
1346 
1347 		case LINK_STATE_DOWN:
1348 			/*
1349 			 * The link is down so send the appropriate
1350 			 * DL_NOTIFY_IND.
1351 			 */
1352 			str_notify_link_down(dsp);
1353 			break;
1354 
1355 		default:
1356 			break;
1357 		}
1358 		break;
1359 
1360 	case MAC_NOTE_RESOURCE:
1361 		/*
1362 		 * This notification is sent whenever the MAC resources
1363 		 * change. We need to renegotiate the capabilities.
1364 		 * Send the appropriate DL_NOTIFY_IND.
1365 		 */
1366 		str_notify_capab_reneg(dsp);
1367 		break;
1368 
1369 	default:
1370 		ASSERT(B_FALSE);
1371 		break;
1372 	}
1373 }
1374 
1375 /*
1376  * Enqueue one or more messages to the transmit queue.
1377  * Caller specifies the insertion position (head/tail).
1378  */
1379 void
1380 dld_tx_enqueue(dld_str_t *dsp, mblk_t *mp, boolean_t head_insert)
1381 {
1382 	mblk_t	*tail;
1383 	queue_t *q = dsp->ds_wq;
1384 	uint_t	cnt, msgcnt;
1385 	uint_t	tot_cnt, tot_msgcnt;
1386 
1387 	ASSERT(DB_TYPE(mp) == M_DATA);
1388 	/* Calculate total size and count of the packet(s) */
1389 	for (tail = mp, cnt = msgdsize(mp), msgcnt = 1;
1390 	    tail->b_next != NULL; tail = tail->b_next) {
1391 		ASSERT(DB_TYPE(tail) == M_DATA);
1392 		cnt += msgdsize(tail);
1393 		msgcnt++;
1394 	}
1395 
1396 	mutex_enter(&dsp->ds_tx_list_lock);
1397 	/*
1398 	 * If the queue depth would exceed the allowed threshold, drop
1399 	 * new packet(s) and drain those already in the queue.
1400 	 */
1401 	tot_cnt = dsp->ds_tx_cnt + cnt;
1402 	tot_msgcnt = dsp->ds_tx_msgcnt + msgcnt;
1403 
1404 	if (!head_insert &&
1405 	    (tot_cnt >= dld_max_q_count || tot_msgcnt >= dld_max_q_count)) {
1406 		ASSERT(dsp->ds_tx_qbusy);
1407 		mutex_exit(&dsp->ds_tx_list_lock);
1408 		freemsgchain(mp);
1409 		goto done;
1410 	}
1411 
1412 	/* Update the queue size parameters */
1413 	dsp->ds_tx_cnt = tot_cnt;
1414 	dsp->ds_tx_msgcnt = tot_msgcnt;
1415 
1416 	/*
1417 	 * If the transmit queue is currently empty and we are
1418 	 * about to deposit the packet(s) there, switch mode to
1419 	 * "busy" and raise flow-control condition.
1420 	 */
1421 	if (!dsp->ds_tx_qbusy) {
1422 		dsp->ds_tx_qbusy = B_TRUE;
1423 		ASSERT(dsp->ds_tx_flow_mp != NULL);
1424 		(void) putq(q, dsp->ds_tx_flow_mp);
1425 		dsp->ds_tx_flow_mp = NULL;
1426 	}
1427 
1428 	if (!head_insert) {
1429 		/* Tail insertion */
1430 		if (dsp->ds_tx_list_head == NULL)
1431 			dsp->ds_tx_list_head = mp;
1432 		else
1433 			dsp->ds_tx_list_tail->b_next = mp;
1434 		dsp->ds_tx_list_tail = tail;
1435 	} else {
1436 		/* Head insertion */
1437 		tail->b_next = dsp->ds_tx_list_head;
1438 		if (dsp->ds_tx_list_head == NULL)
1439 			dsp->ds_tx_list_tail = tail;
1440 		dsp->ds_tx_list_head = mp;
1441 	}
1442 	mutex_exit(&dsp->ds_tx_list_lock);
1443 done:
1444 	/* Schedule service thread to drain the transmit queue */
1445 	qenable(q);
1446 }
1447 
1448 void
1449 dld_tx_flush(dld_str_t *dsp)
1450 {
1451 	mutex_enter(&dsp->ds_tx_list_lock);
1452 	if (dsp->ds_tx_list_head != NULL) {
1453 		freemsgchain(dsp->ds_tx_list_head);
1454 		dsp->ds_tx_list_head = dsp->ds_tx_list_tail = NULL;
1455 		dsp->ds_tx_cnt = dsp->ds_tx_msgcnt = 0;
1456 		if (dsp->ds_tx_qbusy) {
1457 			dsp->ds_tx_flow_mp = getq(dsp->ds_wq);
1458 			ASSERT(dsp->ds_tx_flow_mp != NULL);
1459 			dsp->ds_tx_qbusy = B_FALSE;
1460 		}
1461 	}
1462 	mutex_exit(&dsp->ds_tx_list_lock);
1463 }
1464 
1465 /*
1466  * Process an M_IOCTL message.
1467  */
1468 static void
1469 dld_ioc(dld_str_t *dsp, mblk_t *mp)
1470 {
1471 	uint_t			cmd;
1472 
1473 	cmd = ((struct iocblk *)mp->b_rptr)->ioc_cmd;
1474 	ASSERT(dsp->ds_type == DLD_DLPI);
1475 
1476 	switch (cmd) {
1477 	case DLIOCRAW:
1478 		ioc_raw(dsp, mp);
1479 		break;
1480 	case DLIOCHDRINFO:
1481 		ioc_fast(dsp, mp);
1482 		break;
1483 	default:
1484 		ioc(dsp, mp);
1485 	}
1486 }
1487 
1488 /*
1489  * DLIOCRAW
1490  */
1491 static void
1492 ioc_raw(dld_str_t *dsp, mblk_t *mp)
1493 {
1494 	queue_t *q = dsp->ds_wq;
1495 
1496 	rw_enter(&dsp->ds_lock, RW_WRITER);
1497 	if (dsp->ds_polling) {
1498 		rw_exit(&dsp->ds_lock);
1499 		miocnak(q, mp, 0, EPROTO);
1500 		return;
1501 	}
1502 
1503 	if (dsp->ds_mode != DLD_RAW && dsp->ds_dlstate == DL_IDLE) {
1504 		/*
1505 		 * Set the receive callback.
1506 		 */
1507 		dls_rx_set(dsp->ds_dc, dld_str_rx_raw, (void *)dsp);
1508 
1509 		/*
1510 		 * Note that raw mode is enabled.
1511 		 */
1512 		dsp->ds_mode = DLD_RAW;
1513 	}
1514 
1515 	rw_exit(&dsp->ds_lock);
1516 	miocack(q, mp, 0, 0);
1517 }
1518 
1519 /*
1520  * DLIOCHDRINFO
1521  */
1522 static void
1523 ioc_fast(dld_str_t *dsp, mblk_t *mp)
1524 {
1525 	dl_unitdata_req_t *dlp;
1526 	off_t		off;
1527 	size_t		len;
1528 	const uint8_t	*addr;
1529 	uint16_t	sap;
1530 	mblk_t		*nmp;
1531 	mblk_t		*hmp;
1532 	uint_t		addr_length;
1533 	queue_t		*q = dsp->ds_wq;
1534 	int		err;
1535 	dls_channel_t	dc;
1536 
1537 	if (dld_opt & DLD_OPT_NO_FASTPATH) {
1538 		err = ENOTSUP;
1539 		goto failed;
1540 	}
1541 
1542 	nmp = mp->b_cont;
1543 	if (nmp == NULL || MBLKL(nmp) < sizeof (dl_unitdata_req_t) ||
1544 	    (dlp = (dl_unitdata_req_t *)nmp->b_rptr,
1545 	    dlp->dl_primitive != DL_UNITDATA_REQ)) {
1546 		err = EINVAL;
1547 		goto failed;
1548 	}
1549 
1550 	off = dlp->dl_dest_addr_offset;
1551 	len = dlp->dl_dest_addr_length;
1552 
1553 	if (!MBLKIN(nmp, off, len)) {
1554 		err = EINVAL;
1555 		goto failed;
1556 	}
1557 
1558 	rw_enter(&dsp->ds_lock, RW_READER);
1559 	if (dsp->ds_dlstate != DL_IDLE) {
1560 		rw_exit(&dsp->ds_lock);
1561 		err = ENOTSUP;
1562 		goto failed;
1563 	}
1564 
1565 	addr_length = dsp->ds_mip->mi_addr_length;
1566 	if (len != addr_length + sizeof (uint16_t)) {
1567 		rw_exit(&dsp->ds_lock);
1568 		err = EINVAL;
1569 		goto failed;
1570 	}
1571 
1572 	addr = nmp->b_rptr + off;
1573 	sap = *(uint16_t *)(nmp->b_rptr + off + addr_length);
1574 	dc = dsp->ds_dc;
1575 
1576 	if ((hmp = dls_header(dc, addr, sap, dsp->ds_pri)) == NULL) {
1577 		rw_exit(&dsp->ds_lock);
1578 		err = ENOMEM;
1579 		goto failed;
1580 	}
1581 
1582 	/*
1583 	 * This is a performance optimization.  We originally entered
1584 	 * as reader and only become writer upon transitioning into
1585 	 * the DLD_FASTPATH mode for the first time.  Otherwise we
1586 	 * stay as reader and return the fast-path header to IP.
1587 	 */
1588 	if (dsp->ds_mode != DLD_FASTPATH) {
1589 		if (!rw_tryupgrade(&dsp->ds_lock)) {
1590 			rw_exit(&dsp->ds_lock);
1591 			rw_enter(&dsp->ds_lock, RW_WRITER);
1592 
1593 			/*
1594 			 * State may have changed before we re-acquired
1595 			 * the writer lock in case the upgrade failed.
1596 			 */
1597 			if (dsp->ds_dlstate != DL_IDLE) {
1598 				rw_exit(&dsp->ds_lock);
1599 				err = ENOTSUP;
1600 				goto failed;
1601 			}
1602 		}
1603 
1604 		/*
1605 		 * Set the receive callback (unless polling is enabled).
1606 		 */
1607 		if (!dsp->ds_polling)
1608 			dls_rx_set(dc, dld_str_rx_fastpath, (void *)dsp);
1609 
1610 		/*
1611 		 * Note that fast-path mode is enabled.
1612 		 */
1613 		dsp->ds_mode = DLD_FASTPATH;
1614 	}
1615 	rw_exit(&dsp->ds_lock);
1616 
1617 	freemsg(nmp->b_cont);
1618 	nmp->b_cont = hmp;
1619 
1620 	miocack(q, mp, MBLKL(nmp) + MBLKL(hmp), 0);
1621 	return;
1622 failed:
1623 	miocnak(q, mp, 0, err);
1624 }
1625 
1626 /*
1627  * Catch-all handler.
1628  */
1629 static void
1630 ioc(dld_str_t *dsp, mblk_t *mp)
1631 {
1632 	queue_t	*q = dsp->ds_wq;
1633 	mac_handle_t mh;
1634 
1635 	rw_enter(&dsp->ds_lock, RW_READER);
1636 	if (dsp->ds_dlstate == DL_UNATTACHED) {
1637 		rw_exit(&dsp->ds_lock);
1638 		miocnak(q, mp, 0, EINVAL);
1639 		return;
1640 	}
1641 	mh = dsp->ds_mh;
1642 	ASSERT(mh != NULL);
1643 	rw_exit(&dsp->ds_lock);
1644 	mac_ioctl(mh, q, mp);
1645 }
1646 
1647 /*
1648  * Allocate a new minor number.
1649  */
1650 static minor_t
1651 dld_minor_hold(boolean_t sleep)
1652 {
1653 	minor_t		minor;
1654 
1655 	/*
1656 	 * Grab a value from the arena.
1657 	 */
1658 	atomic_add_32(&minor_count, 1);
1659 	if ((minor = PTR_TO_MINOR(vmem_alloc(minor_arenap, 1,
1660 	    (sleep) ? VM_SLEEP : VM_NOSLEEP))) == 0) {
1661 		atomic_add_32(&minor_count, -1);
1662 		return (0);
1663 	}
1664 
1665 	return (minor);
1666 }
1667 
1668 /*
1669  * Release a previously allocated minor number.
1670  */
1671 static void
1672 dld_minor_rele(minor_t minor)
1673 {
1674 	/*
1675 	 * Return the value to the arena.
1676 	 */
1677 	vmem_free(minor_arenap, MINOR_TO_PTR(minor), 1);
1678 
1679 	atomic_add_32(&minor_count, -1);
1680 }
1681