xref: /titanic_41/usr/src/uts/sun4v/io/ds_pri.c (revision 450396635f70344c58b6b1e4db38cf17ff34445c)
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  * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 
26 
27 /*
28  * sun4v domain services PRI driver
29  */
30 
31 #include <sys/types.h>
32 #include <sys/file.h>
33 #include <sys/errno.h>
34 #include <sys/open.h>
35 #include <sys/cred.h>
36 #include <sys/uio.h>
37 #include <sys/stat.h>
38 #include <sys/ksynch.h>
39 #include <sys/modctl.h>
40 #include <sys/conf.h>
41 #include <sys/devops.h>
42 #include <sys/debug.h>
43 #include <sys/cmn_err.h>
44 #include <sys/ddi.h>
45 #include <sys/sunddi.h>
46 #include <sys/ds.h>
47 
48 #include <sys/ds_pri.h>
49 
50 static uint_t ds_pri_debug = 0;
51 #define	DS_PRI_DBG	if (ds_pri_debug) printf
52 
53 #define	DS_PRI_NAME	"ds_pri"
54 
55 #define	TEST_HARNESS
56 #ifdef TEST_HARNESS
57 #define	DS_PRI_MAX_PRI_SIZE	(64 * 1024)
58 
59 #define	DSIOC_TEST_REG	97
60 #define	DSIOC_TEST_UNREG	98
61 #define	DSIOC_TEST_DATA	99
62 
63 struct ds_pri_test_data {
64 	size_t		size;
65 	void		*data;
66 };
67 
68 struct ds_pri_test_data32 {
69 	size32_t	size;
70 	caddr32_t	data;
71 };
72 #endif /* TEST_HARNESS */
73 
74 typedef	enum {
75 	DS_PRI_REQUEST	= 0,
76 	DS_PRI_DATA	= 1,
77 	DS_PRI_UPDATE	= 2
78 } ds_pri_msg_type_t;
79 
80 typedef	struct {
81 	struct {
82 		uint64_t	seq_num;
83 		uint64_t	type;
84 	} hdr;
85 	uint8_t		data[1];
86 } ds_pri_msg_t;
87 
88 	/* The following are bit field flags */
89 	/* No service implies no PRI and no outstanding request */
90 typedef enum {
91 	DS_PRI_NO_SERVICE = 0x0,
92 	DS_PRI_HAS_SERVICE = 0x1,
93 	DS_PRI_REQUESTED = 0x2,
94 	DS_PRI_HAS_PRI = 0x4
95 } ds_pri_flags_t;
96 
97 struct ds_pri_state {
98 	dev_info_t	*dip;
99 	int		instance;
100 
101 	kmutex_t	lock;
102 	kcondvar_t	cv;
103 
104 	/* PRI/DS */
105 	ds_pri_flags_t	state;
106 	uint64_t	gencount;
107 	ds_svc_hdl_t	ds_pri_handle;
108 	void		*ds_pri;
109 	size_t		ds_pri_len;
110 	uint64_t	req_id;
111 	uint64_t	last_req_id;
112 	int		num_opens;
113 };
114 
115 typedef struct ds_pri_state ds_pri_state_t;
116 
117 static void *ds_pri_statep;
118 
119 static void request_pri(ds_pri_state_t *sp);
120 
121 static int ds_pri_getinfo(dev_info_t *, ddi_info_cmd_t, void *, void **);
122 static int ds_pri_attach(dev_info_t *, ddi_attach_cmd_t);
123 static int ds_pri_detach(dev_info_t *, ddi_detach_cmd_t);
124 static int ds_pri_open(dev_t *, int, int, cred_t *);
125 static int ds_pri_close(dev_t, int, int, cred_t *);
126 static int ds_pri_read(dev_t, struct uio *, cred_t *);
127 static int ds_pri_ioctl(dev_t, int, intptr_t, int, cred_t *, int *);
128 
129 /*
130  * DS Callbacks
131  */
132 static void ds_pri_reg_handler(ds_cb_arg_t, ds_ver_t *, ds_svc_hdl_t);
133 static void ds_pri_unreg_handler(ds_cb_arg_t arg);
134 static void ds_pri_data_handler(ds_cb_arg_t arg, void *buf, size_t buflen);
135 
136 /*
137  * PRI DS capability registration
138  */
139 
140 static ds_ver_t ds_pri_ver_1_0 = { 1, 0 };
141 
142 static ds_capability_t ds_pri_cap = {
143 	"pri",
144 	&ds_pri_ver_1_0,
145 	1
146 };
147 
148 /*
149  * PRI DS Client callback vector
150  */
151 static ds_clnt_ops_t ds_pri_ops = {
152 	ds_pri_reg_handler,	/* ds_reg_cb */
153 	ds_pri_unreg_handler,	/* ds_unreg_cb */
154 	ds_pri_data_handler,	/* ds_data_cb */
155 	NULL			/* cb_arg */
156 };
157 
158 /*
159  * DS PRI driver Ops Vector
160  */
161 static struct cb_ops ds_pri_cb_ops = {
162 	ds_pri_open,		/* cb_open */
163 	ds_pri_close,		/* cb_close */
164 	nodev,			/* cb_strategy */
165 	nodev,			/* cb_print */
166 	nodev,			/* cb_dump */
167 	ds_pri_read,		/* cb_read */
168 	nodev,			/* cb_write */
169 	ds_pri_ioctl,		/* cb_ioctl */
170 	nodev,			/* cb_devmap */
171 	nodev,			/* cb_mmap */
172 	nodev,			/* cb_segmap */
173 	nochpoll,		/* cb_chpoll */
174 	ddi_prop_op,		/* cb_prop_op */
175 	(struct streamtab *)NULL, /* cb_str */
176 	D_MP | D_64BIT,		/* cb_flag */
177 	CB_REV,			/* cb_rev */
178 	nodev,			/* cb_aread */
179 	nodev			/* cb_awrite */
180 };
181 
182 static struct dev_ops ds_pri_dev_ops = {
183 	DEVO_REV,		/* devo_rev */
184 	0,			/* devo_refcnt */
185 	ds_pri_getinfo,		/* devo_getinfo */
186 	nulldev,		/* devo_identify */
187 	nulldev,		/* devo_probe */
188 	ds_pri_attach,		/* devo_attach */
189 	ds_pri_detach,		/* devo_detach */
190 	nodev,			/* devo_reset */
191 	&ds_pri_cb_ops,		/* devo_cb_ops */
192 	(struct bus_ops *)NULL,	/* devo_bus_ops */
193 	nulldev,		/* devo_power */
194 	ddi_quiesce_not_needed,		/* devo_quiesce */
195 };
196 
197 static struct modldrv modldrv = {
198 	&mod_driverops,
199 	"Domain Services PRI Driver",
200 	&ds_pri_dev_ops
201 };
202 
203 static struct modlinkage modlinkage = {
204 	MODREV_1,
205 	(void *)&modldrv,
206 	NULL
207 };
208 
209 
210 int
211 _init(void)
212 {
213 	int retval;
214 
215 	retval = ddi_soft_state_init(&ds_pri_statep,
216 	    sizeof (ds_pri_state_t), 0);
217 	if (retval != 0)
218 		return (retval);
219 
220 	retval = mod_install(&modlinkage);
221 	if (retval != 0) {
222 		ddi_soft_state_fini(&ds_pri_statep);
223 		return (retval);
224 	}
225 
226 	return (retval);
227 }
228 
229 
230 int
231 _info(struct modinfo *modinfop)
232 {
233 	return (mod_info(&modlinkage, modinfop));
234 }
235 
236 
237 int
238 _fini(void)
239 {
240 	int retval;
241 
242 	if ((retval = mod_remove(&modlinkage)) != 0)
243 		return (retval);
244 
245 	ddi_soft_state_fini(&ds_pri_statep);
246 
247 	return (retval);
248 }
249 
250 
251 /*ARGSUSED*/
252 static int
253 ds_pri_getinfo(dev_info_t *dip, ddi_info_cmd_t cmd, void *arg, void **resultp)
254 {
255 	ds_pri_state_t *sp;
256 	int retval = DDI_FAILURE;
257 
258 	ASSERT(resultp != NULL);
259 
260 	switch (cmd) {
261 	case DDI_INFO_DEVT2DEVINFO:
262 		sp = ddi_get_soft_state(ds_pri_statep, getminor((dev_t)arg));
263 		if (sp != NULL) {
264 			*resultp = sp->dip;
265 			retval = DDI_SUCCESS;
266 		} else
267 			*resultp = NULL;
268 		break;
269 
270 	case DDI_INFO_DEVT2INSTANCE:
271 		*resultp = (void *)(uintptr_t)getminor((dev_t)arg);
272 		retval = DDI_SUCCESS;
273 		break;
274 
275 	default:
276 		break;
277 	}
278 
279 	return (retval);
280 }
281 
282 
283 static int
284 ds_pri_attach(dev_info_t *dip, ddi_attach_cmd_t cmd)
285 {
286 	int instance;
287 	ds_pri_state_t *sp;
288 	int rv;
289 
290 	switch (cmd) {
291 	case DDI_ATTACH:
292 		break;
293 
294 	case DDI_RESUME:
295 		return (DDI_SUCCESS);
296 
297 	default:
298 		return (DDI_FAILURE);
299 	}
300 
301 	instance = ddi_get_instance(dip);
302 
303 	if (ddi_soft_state_zalloc(ds_pri_statep, instance) !=
304 	    DDI_SUCCESS) {
305 		cmn_err(CE_WARN, "%s@%d: Unable to allocate state",
306 		    DS_PRI_NAME, instance);
307 		return (DDI_FAILURE);
308 	}
309 	sp = ddi_get_soft_state(ds_pri_statep, instance);
310 
311 	mutex_init(&sp->lock, NULL, MUTEX_DEFAULT, NULL);
312 	cv_init(&sp->cv, NULL, CV_DEFAULT, NULL);
313 
314 	if (ddi_create_minor_node(dip, DS_PRI_NAME, S_IFCHR, instance,
315 	    DDI_PSEUDO, 0) != DDI_SUCCESS) {
316 		cmn_err(CE_WARN, "%s@%d: Unable to create minor node",
317 		    DS_PRI_NAME, instance);
318 		goto fail;
319 	}
320 
321 	if (ds_pri_ops.cb_arg != NULL)
322 		goto fail;
323 	ds_pri_ops.cb_arg = dip;
324 
325 	sp->state = DS_PRI_NO_SERVICE;
326 
327 	/* Until the service registers the handle is invalid */
328 	sp->ds_pri_handle = DS_INVALID_HDL;
329 
330 	sp->ds_pri = NULL;
331 	sp->ds_pri_len = 0;
332 	sp->req_id = 0;
333 	sp->num_opens = 0;
334 
335 	if ((rv = ds_cap_init(&ds_pri_cap, &ds_pri_ops)) != 0) {
336 		cmn_err(CE_NOTE, "ds_cap_init failed: %d", rv);
337 		goto fail;
338 	}
339 
340 	ddi_report_dev(dip);
341 
342 	return (DDI_SUCCESS);
343 
344 fail:
345 	ddi_remove_minor_node(dip, NULL);
346 	cv_destroy(&sp->cv);
347 	mutex_destroy(&sp->lock);
348 	ddi_soft_state_free(ds_pri_statep, instance);
349 	return (DDI_FAILURE);
350 
351 }
352 
353 
354 /*ARGSUSED*/
355 static int
356 ds_pri_detach(dev_info_t *dip, ddi_detach_cmd_t cmd)
357 {
358 	ds_pri_state_t *sp;
359 	int instance;
360 	int rv;
361 
362 	instance = ddi_get_instance(dip);
363 	sp = ddi_get_soft_state(ds_pri_statep, instance);
364 
365 	switch (cmd) {
366 	case DDI_DETACH:
367 		break;
368 
369 	case DDI_SUSPEND:
370 		return (DDI_SUCCESS);
371 
372 	default:
373 		return (DDI_FAILURE);
374 	}
375 
376 	/* This really shouldn't fail - but check anyway */
377 	if ((rv = ds_cap_fini(&ds_pri_cap)) != 0) {
378 		cmn_err(CE_WARN, "ds_cap_fini failed: %d", rv);
379 	}
380 
381 	if (sp != NULL && sp->ds_pri_len != 0)
382 		kmem_free(sp->ds_pri, sp->ds_pri_len);
383 
384 	ds_pri_ops.cb_arg = NULL;
385 
386 	ddi_remove_minor_node(dip, NULL);
387 	cv_destroy(&sp->cv);
388 	mutex_destroy(&sp->lock);
389 	ddi_soft_state_free(ds_pri_statep, instance);
390 
391 	return (DDI_SUCCESS);
392 }
393 
394 
395 /*ARGSUSED*/
396 static int
397 ds_pri_open(dev_t *devp, int flag, int otyp, cred_t *credp)
398 {
399 	ds_pri_state_t *sp;
400 	int instance;
401 
402 	if (otyp != OTYP_CHR)
403 		return (EINVAL);
404 
405 	instance = getminor(*devp);
406 	sp = ddi_get_soft_state(ds_pri_statep, instance);
407 	if (sp == NULL)
408 		return (ENXIO);
409 
410 	mutex_enter(&sp->lock);
411 
412 	/*
413 	 * If we're here and the state is DS_PRI_NO_SERVICE then this
414 	 * means that ds hasn't yet called the registration callback.
415 	 * A while loop is necessary as we might have been woken up
416 	 * prematurely, e.g., due to a debugger or "pstack" etc.
417 	 * Wait here and the callback will signal us when it has completed
418 	 * its work.
419 	 */
420 	while (sp->state == DS_PRI_NO_SERVICE) {
421 		if (cv_wait_sig(&sp->cv, &sp->lock) == 0) {
422 			mutex_exit(&sp->lock);
423 			return (EINTR);
424 		}
425 	}
426 
427 	sp->num_opens++;
428 	mutex_exit(&sp->lock);
429 
430 	/*
431 	 * On open we dont fetch the PRI even if we have a valid service
432 	 * handle. PRI fetch is essentially lazy and on-demand.
433 	 */
434 
435 	DS_PRI_DBG("ds_pri_open: state = 0x%x\n", sp->state);
436 
437 	return (0);
438 }
439 
440 
441 /*ARGSUSED*/
442 static int
443 ds_pri_close(dev_t dev, int flag, int otyp, cred_t *credp)
444 {
445 	int instance;
446 	ds_pri_state_t *sp;
447 
448 	if (otyp != OTYP_CHR)
449 		return (EINVAL);
450 
451 	DS_PRI_DBG("ds_pri_close\n");
452 
453 	instance = getminor(dev);
454 	if ((sp = ddi_get_soft_state(ds_pri_statep, instance)) == NULL)
455 		return (ENXIO);
456 
457 	mutex_enter(&sp->lock);
458 	if (!(sp->state & DS_PRI_HAS_SERVICE)) {
459 		mutex_exit(&sp->lock);
460 		return (0);
461 	}
462 
463 	if (--sp->num_opens > 0) {
464 		mutex_exit(&sp->lock);
465 		return (0);
466 	}
467 
468 	/* If we have an old PRI - remove it */
469 	if (sp->state & DS_PRI_HAS_PRI) {
470 		if (sp->ds_pri != NULL && sp->ds_pri_len > 0) {
471 			/*
472 			 * remove the old data if we have an
473 			 * outstanding request
474 			 */
475 			kmem_free(sp->ds_pri, sp->ds_pri_len);
476 			sp->ds_pri_len = 0;
477 			sp->ds_pri = NULL;
478 		}
479 		sp->state &= ~DS_PRI_HAS_PRI;
480 	}
481 	sp->state &= ~DS_PRI_REQUESTED;
482 	mutex_exit(&sp->lock);
483 	return (0);
484 }
485 
486 
487 /*ARGSUSED*/
488 static int
489 ds_pri_read(dev_t dev, struct uio *uiop, cred_t *credp)
490 {
491 	ds_pri_state_t *sp;
492 	int instance;
493 	size_t len;
494 	int retval;
495 	caddr_t tmpbufp;
496 	offset_t off = uiop->uio_offset;
497 
498 	instance = getminor(dev);
499 	if ((sp = ddi_get_soft_state(ds_pri_statep, instance)) == NULL)
500 		return (ENXIO);
501 
502 	len = uiop->uio_resid;
503 
504 	if (len == 0)
505 		return (0);
506 
507 	mutex_enter(&sp->lock);
508 
509 	DS_PRI_DBG("ds_pri_read: state = 0x%x\n", sp->state);
510 
511 	/* block or bail if there is no current PRI */
512 	if (!(sp->state & DS_PRI_HAS_PRI)) {
513 		DS_PRI_DBG("ds_pri_read: no PRI held\n");
514 
515 		if (uiop->uio_fmode & (FNDELAY | FNONBLOCK)) {
516 			mutex_exit(&sp->lock);
517 			return (EAGAIN);
518 		}
519 
520 		while (!(sp->state & DS_PRI_HAS_PRI)) {
521 			DS_PRI_DBG("ds_pri_read: state = 0x%x\n", sp->state);
522 			request_pri(sp);
523 			if (cv_wait_sig(&sp->cv, &sp->lock) == 0) {
524 				mutex_exit(&sp->lock);
525 				return (EINTR);
526 			}
527 		}
528 	}
529 
530 	if (len > sp->ds_pri_len)
531 		len = sp->ds_pri_len;
532 
533 	if (len == 0) {
534 		mutex_exit(&sp->lock);
535 		return (0);
536 	}
537 
538 	/*
539 	 * We're supposed to move the data out to userland, but
540 	 * that can suspend because of page faults etc., and meanwhile
541 	 * other parts of this driver want to update the PRI buffer ...
542 	 * we could hold the data buffer locked with a flag etc.,
543 	 * but that's still a lock ... a simpler mechanism - if not quite
544 	 * as performance efficient is to simply clone here the part of
545 	 * the buffer we care about and then the original can be released
546 	 * for further updates while the uiomove continues.
547 	 */
548 
549 	tmpbufp = kmem_alloc(len, KM_SLEEP);
550 	bcopy(((caddr_t)sp->ds_pri), tmpbufp, len);
551 	mutex_exit(&sp->lock);
552 
553 	retval = uiomove(tmpbufp, len, UIO_READ, uiop);
554 
555 	kmem_free(tmpbufp, len);
556 
557 	/*
558 	 * restore uio_offset after uiomove since the driver
559 	 * does not support the concept of position.
560 	 */
561 	uiop->uio_offset = off;
562 
563 	return (retval);
564 }
565 
566 
567 /*ARGSUSED*/
568 static int
569 ds_pri_ioctl(dev_t dev, int cmd, intptr_t arg, int mode, cred_t *credp,
570     int *rvalp)
571 {
572 	ds_pri_state_t *sp;
573 	int instance;
574 
575 	instance = getminor(dev);
576 	if ((sp = ddi_get_soft_state(ds_pri_statep, instance)) == NULL)
577 		return (ENXIO);
578 
579 	switch (cmd) {
580 	case DSPRI_GETINFO: {
581 		struct dspri_info info;
582 
583 		if (!(mode & FREAD))
584 			return (EACCES);
585 
586 		/*
587 		 * We are not guaranteed that ddi_copyout(9F) will read
588 		 * atomically anything larger than a byte.  Therefore we
589 		 * must duplicate the size before copying it out to the user.
590 		 */
591 		mutex_enter(&sp->lock);
592 
593 loop:;
594 		if (sp->state & DS_PRI_HAS_PRI) {
595 			/* If we have a PRI simply return the info */
596 			info.size = sp->ds_pri_len;
597 			info.token = sp->gencount;
598 		} else
599 		if (!(sp->state & DS_PRI_HAS_SERVICE)) {
600 			/* If we have no service return a nil response */
601 			info.size = 0;
602 			info.token = 0;
603 		} else {
604 			request_pri(sp);
605 			/* wait for something & check again */
606 			if (cv_wait_sig(&sp->cv, &sp->lock) == 0) {
607 				mutex_exit(&sp->lock);
608 				return (EINTR);
609 			}
610 			goto loop;
611 		}
612 		DS_PRI_DBG("ds_pri_ioctl: DSPRI_GETINFO sz=0x%lx tok=0x%lx\n",
613 		    info.size, info.token);
614 		mutex_exit(&sp->lock);
615 
616 		if (ddi_copyout(&info, (void *)arg, sizeof (info), mode) != 0)
617 			return (EFAULT);
618 		break;
619 	}
620 
621 	case DSPRI_WAIT: {
622 		uint64_t gencount;
623 
624 		if (ddi_copyin((void *)arg, &gencount, sizeof (gencount),
625 		    mode) != 0)
626 			return (EFAULT);
627 
628 		mutex_enter(&sp->lock);
629 
630 		DS_PRI_DBG("ds_pri_ioctl: DSPRI_WAIT gen=0x%lx sp->gen=0x%lx\n",
631 		    gencount, sp->gencount);
632 
633 		while ((sp->state & DS_PRI_HAS_PRI) == 0 ||
634 		    gencount == sp->gencount) {
635 			if ((sp->state & DS_PRI_HAS_PRI) == 0)
636 				request_pri(sp);
637 			if (cv_wait_sig(&sp->cv, &sp->lock) == 0) {
638 				mutex_exit(&sp->lock);
639 				return (EINTR);
640 			}
641 		}
642 		mutex_exit(&sp->lock);
643 		break;
644 	}
645 
646 	default:
647 		return (ENOTTY);
648 	}
649 	return (0);
650 }
651 
652 
653 	/* assumes sp->lock is held when called */
654 static void
655 request_pri(ds_pri_state_t *sp)
656 {
657 	ds_pri_msg_t reqmsg;
658 
659 	ASSERT(MUTEX_HELD(&sp->lock));
660 
661 	/* If a request is already pending we're done */
662 	if (!(sp->state & DS_PRI_HAS_SERVICE))
663 		return;
664 	if (sp->state & DS_PRI_REQUESTED)
665 		return;
666 
667 	/* If we have an old PRI - remove it */
668 	if (sp->state & DS_PRI_HAS_PRI) {
669 		ASSERT(sp->ds_pri_len != 0);
670 		ASSERT(sp->ds_pri != NULL);
671 
672 		/* remove the old data if we have an outstanding request */
673 		kmem_free(sp->ds_pri, sp->ds_pri_len);
674 		sp->ds_pri_len = 0;
675 		sp->ds_pri = NULL;
676 		sp->state &= ~DS_PRI_HAS_PRI;
677 	} else {
678 		ASSERT(sp->ds_pri == NULL);
679 		ASSERT(sp->ds_pri_len == 0);
680 	}
681 
682 	reqmsg.hdr.seq_num = ++(sp->req_id);
683 	reqmsg.hdr.type = DS_PRI_REQUEST;
684 
685 	DS_PRI_DBG("request_pri: request id 0x%lx\n", sp->req_id);
686 
687 		/*
688 		 * Request consists of header only.
689 		 * We don't care about fail status for ds_send;
690 		 * if it does fail we will get an unregister callback
691 		 * from the DS framework and we handle the state change
692 		 * there.
693 		 */
694 	(void) ds_cap_send(sp->ds_pri_handle, &reqmsg, sizeof (reqmsg.hdr));
695 
696 	sp->state |= DS_PRI_REQUESTED;
697 	sp->last_req_id = sp->req_id;
698 }
699 
700 /*
701  * DS Callbacks
702  */
703 /*ARGSUSED*/
704 static void
705 ds_pri_reg_handler(ds_cb_arg_t arg, ds_ver_t *ver, ds_svc_hdl_t hdl)
706 {
707 	dev_info_t *dip = arg;
708 	ds_pri_state_t *sp;
709 	int instance;
710 
711 	instance = ddi_get_instance(dip);
712 	if ((sp = ddi_get_soft_state(ds_pri_statep, instance)) == NULL)
713 		return;
714 
715 	DS_PRI_DBG("ds_pri_reg_handler: registering handle 0x%lx for version "
716 	    "0x%x:0x%x\n", (uint64_t)hdl, ver->major, ver->minor);
717 
718 	/* When the domain service comes up automatically req the pri */
719 	mutex_enter(&sp->lock);
720 
721 	ASSERT(sp->ds_pri_handle == DS_INVALID_HDL);
722 	sp->ds_pri_handle = hdl;
723 
724 	ASSERT(sp->state == DS_PRI_NO_SERVICE);
725 	ASSERT(sp->ds_pri == NULL);
726 	ASSERT(sp->ds_pri_len == 0);
727 
728 	/* have service, but no PRI */
729 	sp->state |= DS_PRI_HAS_SERVICE;
730 
731 	/*
732 	 * Cannot request a PRI here, because the reg handler cannot
733 	 * do a DS send operation - we take care of this later.
734 	 */
735 
736 	/* Wake up anyone waiting in open() */
737 	cv_broadcast(&sp->cv);
738 
739 	mutex_exit(&sp->lock);
740 }
741 
742 
743 static void
744 ds_pri_unreg_handler(ds_cb_arg_t arg)
745 {
746 	dev_info_t *dip = arg;
747 	ds_pri_state_t *sp;
748 	int instance;
749 
750 	instance = ddi_get_instance(dip);
751 	if ((sp = ddi_get_soft_state(ds_pri_statep, instance)) == NULL)
752 		return;
753 
754 	DS_PRI_DBG("ds_pri_unreg_handler: un-registering ds_pri service\n");
755 
756 	mutex_enter(&sp->lock);
757 
758 	/* Once the service goes - if we have a PRI at hand free it up */
759 	if (sp->ds_pri_len != 0) {
760 		kmem_free(sp->ds_pri, sp->ds_pri_len);
761 		sp->ds_pri_len = 0;
762 		sp->ds_pri = NULL;
763 	}
764 	sp->ds_pri_handle = DS_INVALID_HDL;
765 	sp->state = DS_PRI_NO_SERVICE;
766 
767 	mutex_exit(&sp->lock);
768 }
769 
770 
771 static void
772 ds_pri_data_handler(ds_cb_arg_t arg, void *buf, size_t buflen)
773 {
774 	dev_info_t *dip = arg;
775 	ds_pri_state_t *sp;
776 	int instance;
777 	void *data;
778 	ds_pri_msg_t	*msgp;
779 	size_t	pri_size;
780 
781 	msgp = (ds_pri_msg_t *)buf;
782 
783 	/* make sure the header is at least valid */
784 	if (buflen < sizeof (msgp->hdr))
785 		return;
786 
787 	DS_PRI_DBG("ds_pri_data_handler: msg buf len 0x%lx : type 0x%lx, "
788 	    "seqn 0x%lx\n", buflen, msgp->hdr.type, msgp->hdr.seq_num);
789 
790 	instance = ddi_get_instance(dip);
791 	if ((sp = ddi_get_soft_state(ds_pri_statep, instance)) == NULL)
792 		return;
793 
794 	mutex_enter(&sp->lock);
795 
796 	ASSERT(sp->state & DS_PRI_HAS_SERVICE);
797 
798 	switch (msgp->hdr.type) {
799 	case DS_PRI_DATA:	/* in response to a request from us */
800 		break;
801 	case DS_PRI_UPDATE:	/* aynch notification */
802 			/* our default response to this is to request the PRI */
803 		/* simply issue a request for the new PRI */
804 		request_pri(sp);
805 		goto done;
806 	default:	/* ignore garbage or unknown message types */
807 		goto done;
808 	}
809 
810 	/*
811 	 * If there is no pending PRI request, then we've received a
812 	 * bogus data message ... so ignore it.
813 	 */
814 
815 	if (!(sp->state & DS_PRI_REQUESTED)) {
816 		cmn_err(CE_WARN, "Received DS pri data without request");
817 		goto done;
818 	}
819 
820 	/* response to a request therefore old PRI must be gone */
821 	ASSERT(!(sp->state & DS_PRI_HAS_PRI));
822 	ASSERT(sp->ds_pri_len == 0);
823 	ASSERT(sp->ds_pri == NULL);
824 
825 	/* response seq_num should match our request seq_num */
826 	if (msgp->hdr.seq_num != sp->last_req_id) {
827 		cmn_err(CE_WARN, "Received DS pri data out of sequence with "
828 		    "request");
829 		goto done;
830 	}
831 
832 	pri_size = buflen - sizeof (msgp->hdr);
833 	data = kmem_alloc(pri_size, KM_SLEEP);
834 	sp->ds_pri = data;
835 	sp->ds_pri_len = pri_size;
836 	bcopy(msgp->data, data, sp->ds_pri_len);
837 	sp->state &= ~DS_PRI_REQUESTED;
838 	sp->state |= DS_PRI_HAS_PRI;
839 
840 	sp->gencount++;
841 	cv_broadcast(&sp->cv);
842 
843 done:;
844 	mutex_exit(&sp->lock);
845 }
846