xref: /illumos-gate/usr/src/uts/common/fs/sockfs/sockcommon_subr.c (revision 86c48bbfeb72d5a6ee171e713059939bab658b77)
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/param.h>
29 #include <sys/signal.h>
30 #include <sys/cmn_err.h>
31 
32 #include <sys/stropts.h>
33 #include <sys/socket.h>
34 #include <sys/socketvar.h>
35 #include <sys/sockio.h>
36 #include <sys/sodirect.h>
37 #include <sys/strsubr.h>
38 #include <sys/strsun.h>
39 #include <sys/atomic.h>
40 
41 #include <fs/sockfs/sockcommon.h>
42 #include <fs/sockfs/socktpi.h>
43 #include <sys/ddi.h>
44 #include <inet/ip.h>
45 #include <sys/time.h>
46 #include <sys/cmn_err.h>
47 
48 #ifdef SOCK_TEST
49 extern int do_useracc;
50 extern clock_t sock_test_timelimit;
51 #endif /* SOCK_TEST */
52 
53 #define	MBLK_PULL_LEN 64
54 uint32_t so_mblk_pull_len = MBLK_PULL_LEN;
55 
56 #ifdef DEBUG
57 boolean_t so_debug_length = B_FALSE;
58 static boolean_t so_check_length(sonode_t *so);
59 #endif
60 
61 int
62 so_acceptq_enqueue_locked(struct sonode *so, struct sonode *nso)
63 {
64 	ASSERT(MUTEX_HELD(&so->so_acceptq_lock));
65 	ASSERT(nso->so_acceptq_next == NULL);
66 
67 	*so->so_acceptq_tail = nso;
68 	so->so_acceptq_tail = &nso->so_acceptq_next;
69 	so->so_acceptq_len++;
70 
71 	/* Wakeup a single consumer */
72 	cv_signal(&so->so_acceptq_cv);
73 
74 	return (so->so_acceptq_len);
75 }
76 
77 /*
78  * int so_acceptq_enqueue(struct sonode *so, struct sonode *nso)
79  *
80  * Enqueue an incoming connection on a listening socket.
81  *
82  * Arguments:
83  *   so	  - listening socket
84  *   nso  - new connection
85  *
86  * Returns:
87  *   Number of queued connections, including the new connection
88  */
89 int
90 so_acceptq_enqueue(struct sonode *so, struct sonode *nso)
91 {
92 	int conns;
93 
94 	mutex_enter(&so->so_acceptq_lock);
95 	conns = so_acceptq_enqueue_locked(so, nso);
96 	mutex_exit(&so->so_acceptq_lock);
97 
98 	return (conns);
99 }
100 
101 static int
102 so_acceptq_dequeue_locked(struct sonode *so, boolean_t dontblock,
103     struct sonode **nsop)
104 {
105 	struct sonode *nso = NULL;
106 
107 	*nsop = NULL;
108 	ASSERT(MUTEX_HELD(&so->so_acceptq_lock));
109 	while ((nso = so->so_acceptq_head) == NULL) {
110 		/*
111 		 * No need to check so_error here, because it is not
112 		 * possible for a listening socket to be reset or otherwise
113 		 * disconnected.
114 		 *
115 		 * So now we just need check if it's ok to wait.
116 		 */
117 		if (dontblock)
118 			return (EWOULDBLOCK);
119 		if (so->so_state & (SS_CLOSING | SS_FALLBACK_PENDING))
120 			return (EINTR);
121 
122 		if (cv_wait_sig_swap(&so->so_acceptq_cv,
123 		    &so->so_acceptq_lock) == 0)
124 			return (EINTR);
125 	}
126 
127 	ASSERT(nso != NULL);
128 	so->so_acceptq_head = nso->so_acceptq_next;
129 	nso->so_acceptq_next = NULL;
130 
131 	if (so->so_acceptq_head == NULL) {
132 		ASSERT(so->so_acceptq_tail == &nso->so_acceptq_next);
133 		so->so_acceptq_tail = &so->so_acceptq_head;
134 	}
135 	ASSERT(so->so_acceptq_len > 0);
136 	--so->so_acceptq_len;
137 
138 	*nsop = nso;
139 
140 	return (0);
141 }
142 
143 /*
144  * int so_acceptq_dequeue(struct sonode *, boolean_t, struct sonode **)
145  *
146  * Pulls a connection off of the accept queue.
147  *
148  * Arguments:
149  *   so	       - listening socket
150  *   dontblock - indicate whether it's ok to sleep if there are no
151  *		 connections on the queue
152  *   nsop      - Value-return argument
153  *
154  * Return values:
155  *   0 when a connection is successfully dequeued, in which case nsop
156  *   is set to point to the new connection. Upon failure a non-zero
157  *   value is returned, and the value of nsop is set to NULL.
158  *
159  * Note:
160  *   so_acceptq_dequeue() may return prematurly if the socket is falling
161  *   back to TPI.
162  */
163 int
164 so_acceptq_dequeue(struct sonode *so, boolean_t dontblock,
165     struct sonode **nsop)
166 {
167 	int error;
168 
169 	mutex_enter(&so->so_acceptq_lock);
170 	error = so_acceptq_dequeue_locked(so, dontblock, nsop);
171 	mutex_exit(&so->so_acceptq_lock);
172 
173 	return (error);
174 }
175 
176 /*
177  * void so_acceptq_flush(struct sonode *so)
178  *
179  * Removes all pending connections from a listening socket, and
180  * frees the associated resources.
181  *
182  * Arguments
183  *   so	    - listening socket
184  *
185  * Return values:
186  *   None.
187  *
188  * Note:
189  *   The caller has to ensure that no calls to so_acceptq_enqueue() or
190  *   so_acceptq_dequeue() occur while the accept queue is being flushed.
191  *   So either the socket needs to be in a state where no operations
192  *   would come in, or so_lock needs to be obtained.
193  */
194 void
195 so_acceptq_flush(struct sonode *so)
196 {
197 	struct sonode *nso;
198 
199 	nso = so->so_acceptq_head;
200 
201 	while (nso != NULL) {
202 		struct sonode *nnso = NULL;
203 
204 		nnso = nso->so_acceptq_next;
205 		nso->so_acceptq_next = NULL;
206 		/*
207 		 * Since the socket is on the accept queue, there can
208 		 * only be one reference. We drop the reference and
209 		 * just blow off the socket.
210 		 */
211 		ASSERT(nso->so_count == 1);
212 		nso->so_count--;
213 		socket_destroy(nso);
214 		nso = nnso;
215 	}
216 
217 	so->so_acceptq_head = NULL;
218 	so->so_acceptq_tail = &so->so_acceptq_head;
219 	so->so_acceptq_len = 0;
220 }
221 
222 int
223 so_wait_connected_locked(struct sonode *so, boolean_t nonblock,
224     sock_connid_t id)
225 {
226 	ASSERT(MUTEX_HELD(&so->so_lock));
227 
228 	/*
229 	 * The protocol has notified us that a connection attempt is being
230 	 * made, so before we wait for a notification to arrive we must
231 	 * clear out any errors associated with earlier connection attempts.
232 	 */
233 	if (so->so_error != 0 && SOCK_CONNID_LT(so->so_proto_connid, id))
234 		so->so_error = 0;
235 
236 	while (SOCK_CONNID_LT(so->so_proto_connid, id)) {
237 		if (nonblock)
238 			return (EINPROGRESS);
239 
240 		if (so->so_state & (SS_CLOSING | SS_FALLBACK_PENDING))
241 			return (EINTR);
242 
243 		if (cv_wait_sig_swap(&so->so_state_cv, &so->so_lock) == 0)
244 			return (EINTR);
245 	}
246 
247 	if (so->so_error != 0)
248 		return (sogeterr(so, B_TRUE));
249 	/*
250 	 * Under normal circumstances, so_error should contain an error
251 	 * in case the connect failed. However, it is possible for another
252 	 * thread to come in a consume the error, so generate a sensible
253 	 * error in that case.
254 	 */
255 	if ((so->so_state & SS_ISCONNECTED) == 0)
256 		return (ECONNREFUSED);
257 
258 	return (0);
259 }
260 
261 /*
262  * int so_wait_connected(struct sonode *so, boolean_t nonblock,
263  *    sock_connid_t id)
264  *
265  * Wait until the socket is connected or an error has occured.
266  *
267  * Arguments:
268  *   so	      - socket
269  *   nonblock - indicate whether it's ok to sleep if the connection has
270  *		not yet been established
271  *   gen      - generation number that was returned by the protocol
272  *		when the operation was started
273  *
274  * Returns:
275  *   0 if the connection attempt was successful, or an error indicating why
276  *   the connection attempt failed.
277  */
278 int
279 so_wait_connected(struct sonode *so, boolean_t nonblock, sock_connid_t id)
280 {
281 	int error;
282 
283 	mutex_enter(&so->so_lock);
284 	error = so_wait_connected_locked(so, nonblock, id);
285 	mutex_exit(&so->so_lock);
286 
287 	return (error);
288 }
289 
290 int
291 so_snd_wait_qnotfull_locked(struct sonode *so, boolean_t dontblock)
292 {
293 	int error;
294 
295 	ASSERT(MUTEX_HELD(&so->so_lock));
296 	while (so->so_snd_qfull) {
297 		if (so->so_state & SS_CANTSENDMORE)
298 			return (EPIPE);
299 		if (dontblock)
300 			return (EWOULDBLOCK);
301 
302 		if (so->so_state & (SS_CLOSING | SS_FALLBACK_PENDING))
303 			return (EINTR);
304 
305 		if (so->so_sndtimeo == 0) {
306 			/*
307 			 * Zero means disable timeout.
308 			 */
309 			error = cv_wait_sig(&so->so_snd_cv, &so->so_lock);
310 		} else {
311 			clock_t now;
312 
313 			time_to_wait(&now, so->so_sndtimeo);
314 			error = cv_timedwait_sig(&so->so_snd_cv, &so->so_lock,
315 			    now);
316 		}
317 		if (error == 0)
318 			return (EINTR);
319 		else if (error == -1)
320 			return (EAGAIN);
321 	}
322 	return (0);
323 }
324 
325 /*
326  * int so_wait_sendbuf(struct sonode *so, boolean_t dontblock)
327  *
328  * Wait for the transport to notify us about send buffers becoming
329  * available.
330  */
331 int
332 so_snd_wait_qnotfull(struct sonode *so, boolean_t dontblock)
333 {
334 	int error = 0;
335 
336 	mutex_enter(&so->so_lock);
337 	if (so->so_snd_qfull) {
338 		so->so_snd_wakeup = B_TRUE;
339 		error = so_snd_wait_qnotfull_locked(so, dontblock);
340 		so->so_snd_wakeup = B_FALSE;
341 	}
342 	mutex_exit(&so->so_lock);
343 
344 	return (error);
345 }
346 
347 void
348 so_snd_qfull(struct sonode *so)
349 {
350 	mutex_enter(&so->so_lock);
351 	so->so_snd_qfull = B_TRUE;
352 	mutex_exit(&so->so_lock);
353 }
354 
355 void
356 so_snd_qnotfull(struct sonode *so)
357 {
358 	mutex_enter(&so->so_lock);
359 	so->so_snd_qfull = B_FALSE;
360 	/* wake up everyone waiting for buffers */
361 	cv_broadcast(&so->so_snd_cv);
362 	mutex_exit(&so->so_lock);
363 }
364 
365 /*
366  * Change the process/process group to which SIGIO is sent.
367  */
368 int
369 socket_chgpgrp(struct sonode *so, pid_t pid)
370 {
371 	int error;
372 
373 	ASSERT(MUTEX_HELD(&so->so_lock));
374 	if (pid != 0) {
375 		/*
376 		 * Permissions check by sending signal 0.
377 		 * Note that when kill fails it does a
378 		 * set_errno causing the system call to fail.
379 		 */
380 		error = kill(pid, 0);
381 		if (error != 0) {
382 			return (error);
383 		}
384 	}
385 	so->so_pgrp = pid;
386 	return (0);
387 }
388 
389 
390 /*
391  * Generate a SIGIO, for 'writable' events include siginfo structure,
392  * for read events just send the signal.
393  */
394 /*ARGSUSED*/
395 static void
396 socket_sigproc(proc_t *proc, int event)
397 {
398 	k_siginfo_t info;
399 
400 	ASSERT(event & (SOCKETSIG_WRITE | SOCKETSIG_READ | SOCKETSIG_URG));
401 
402 	if (event & SOCKETSIG_WRITE) {
403 		info.si_signo = SIGPOLL;
404 		info.si_code = POLL_OUT;
405 		info.si_errno = 0;
406 		info.si_fd = 0;
407 		info.si_band = 0;
408 		sigaddq(proc, NULL, &info, KM_NOSLEEP);
409 	}
410 	if (event & SOCKETSIG_READ) {
411 		sigtoproc(proc, NULL, SIGPOLL);
412 	}
413 	if (event & SOCKETSIG_URG) {
414 		sigtoproc(proc, NULL, SIGURG);
415 	}
416 }
417 
418 void
419 socket_sendsig(struct sonode *so, int event)
420 {
421 	proc_t *proc;
422 
423 	ASSERT(MUTEX_HELD(&so->so_lock));
424 
425 	if (so->so_pgrp == 0 || (!(so->so_state & SS_ASYNC) &&
426 	    event != SOCKETSIG_URG)) {
427 		return;
428 	}
429 
430 	dprint(3, ("sending sig %d to %d\n", event, so->so_pgrp));
431 
432 	if (so->so_pgrp > 0) {
433 		/*
434 		 * XXX This unfortunately still generates
435 		 * a signal when a fd is closed but
436 		 * the proc is active.
437 		 */
438 		mutex_enter(&pidlock);
439 		proc = prfind(so->so_pgrp);
440 		if (proc == NULL) {
441 			mutex_exit(&pidlock);
442 			return;
443 		}
444 		mutex_enter(&proc->p_lock);
445 		mutex_exit(&pidlock);
446 		socket_sigproc(proc, event);
447 		mutex_exit(&proc->p_lock);
448 	} else {
449 		/*
450 		 * Send to process group. Hold pidlock across
451 		 * calls to socket_sigproc().
452 		 */
453 		pid_t pgrp = -so->so_pgrp;
454 
455 		mutex_enter(&pidlock);
456 		proc = pgfind(pgrp);
457 		while (proc != NULL) {
458 			mutex_enter(&proc->p_lock);
459 			socket_sigproc(proc, event);
460 			mutex_exit(&proc->p_lock);
461 			proc = proc->p_pglink;
462 		}
463 		mutex_exit(&pidlock);
464 	}
465 }
466 
467 #define	MIN(a, b) ((a) < (b) ? (a) : (b))
468 /* Copy userdata into a new mblk_t */
469 mblk_t *
470 socopyinuio(uio_t *uiop, ssize_t iosize, size_t wroff, ssize_t maxblk,
471     size_t tail_len, int *errorp, cred_t *cr)
472 {
473 	mblk_t	*head = NULL, **tail = &head;
474 
475 	ASSERT(iosize == INFPSZ || iosize > 0);
476 
477 	if (iosize == INFPSZ || iosize > uiop->uio_resid)
478 		iosize = uiop->uio_resid;
479 
480 	if (maxblk == INFPSZ)
481 		maxblk = iosize;
482 
483 	/* Nothing to do in these cases, so we're done */
484 	if (iosize < 0 || maxblk < 0 || (maxblk == 0 && iosize > 0))
485 		goto done;
486 
487 	/*
488 	 * We will enter the loop below if iosize is 0; it will allocate an
489 	 * empty message block and call uiomove(9F) which will just return.
490 	 * We could avoid that with an extra check but would only slow
491 	 * down the much more likely case where iosize is larger than 0.
492 	 */
493 	do {
494 		ssize_t blocksize;
495 		mblk_t	*mp;
496 
497 		blocksize = MIN(iosize, maxblk);
498 		ASSERT(blocksize >= 0);
499 		if (is_system_labeled())
500 			mp = allocb_cred(wroff + blocksize + tail_len,
501 			    cr, curproc->p_pid);
502 		else
503 			mp = allocb(wroff + blocksize + tail_len, BPRI_MED);
504 		if (mp == NULL) {
505 			*errorp = ENOMEM;
506 			return (head);
507 		}
508 		mp->b_rptr += wroff;
509 		mp->b_wptr = mp->b_rptr + blocksize;
510 
511 		*tail = mp;
512 		tail = &mp->b_cont;
513 
514 		/* uiomove(9F) either returns 0 or EFAULT */
515 		if ((*errorp = uiomove(mp->b_rptr, (size_t)blocksize,
516 		    UIO_WRITE, uiop)) != 0) {
517 			ASSERT(*errorp != ENOMEM);
518 			freemsg(head);
519 			return (NULL);
520 		}
521 
522 		iosize -= blocksize;
523 	} while (iosize > 0);
524 
525 done:
526 	*errorp = 0;
527 	return (head);
528 }
529 
530 mblk_t *
531 socopyoutuio(mblk_t *mp, struct uio *uiop, ssize_t max_read, int *errorp)
532 {
533 	int error;
534 	ptrdiff_t n;
535 	mblk_t *nmp;
536 
537 	ASSERT(mp->b_wptr >= mp->b_rptr);
538 
539 	/*
540 	 * max_read is the offset of the oobmark and read can not go pass
541 	 * the oobmark.
542 	 */
543 	if (max_read == INFPSZ || max_read > uiop->uio_resid)
544 		max_read = uiop->uio_resid;
545 
546 	do {
547 		if ((n = MIN(max_read, MBLKL(mp))) != 0) {
548 			ASSERT(n > 0);
549 
550 			error = uiomove(mp->b_rptr, n, UIO_READ, uiop);
551 			if (error != 0) {
552 				freemsg(mp);
553 				*errorp = error;
554 				return (NULL);
555 			}
556 		}
557 
558 		mp->b_rptr += n;
559 		max_read -= n;
560 		while (mp != NULL && (mp->b_rptr >= mp->b_wptr)) {
561 			/*
562 			 * get rid of zero length mblks
563 			 */
564 			nmp = mp;
565 			mp = mp->b_cont;
566 			freeb(nmp);
567 		}
568 	} while (mp != NULL && max_read > 0);
569 
570 	*errorp = 0;
571 	return (mp);
572 }
573 
574 static void
575 so_prepend_msg(struct sonode *so, mblk_t *mp, mblk_t *last_tail)
576 {
577 	ASSERT(last_tail != NULL);
578 	mp->b_next = so->so_rcv_q_head;
579 	mp->b_prev = last_tail;
580 	ASSERT(!(DB_FLAGS(mp) & DBLK_UIOA));
581 
582 	if (so->so_rcv_q_head == NULL) {
583 		ASSERT(so->so_rcv_q_last_head == NULL);
584 		so->so_rcv_q_last_head = mp;
585 #ifdef DEBUG
586 	} else {
587 		ASSERT(!(DB_FLAGS(so->so_rcv_q_head) & DBLK_UIOA));
588 #endif
589 	}
590 	so->so_rcv_q_head = mp;
591 
592 #ifdef DEBUG
593 	if (so_debug_length) {
594 		mutex_enter(&so->so_lock);
595 		ASSERT(so_check_length(so));
596 		mutex_exit(&so->so_lock);
597 	}
598 #endif
599 }
600 
601 static void
602 process_new_message(struct sonode *so, mblk_t *mp_head, mblk_t *mp_last_head)
603 {
604 	ASSERT(mp_head->b_prev != NULL);
605 	if (so->so_rcv_q_head  == NULL) {
606 		so->so_rcv_q_head = mp_head;
607 		so->so_rcv_q_last_head = mp_last_head;
608 		ASSERT(so->so_rcv_q_last_head->b_prev != NULL);
609 	} else {
610 		boolean_t flag_equal = ((DB_FLAGS(mp_head) & DBLK_UIOA) ==
611 		    (DB_FLAGS(so->so_rcv_q_last_head) & DBLK_UIOA));
612 
613 		if (mp_head->b_next == NULL &&
614 		    DB_TYPE(mp_head) == M_DATA &&
615 		    DB_TYPE(so->so_rcv_q_last_head) == M_DATA && flag_equal) {
616 			so->so_rcv_q_last_head->b_prev->b_cont = mp_head;
617 			so->so_rcv_q_last_head->b_prev = mp_head->b_prev;
618 			mp_head->b_prev = NULL;
619 		} else if (flag_equal && (DB_FLAGS(mp_head) & DBLK_UIOA)) {
620 			/*
621 			 * Append to last_head if more than one mblks, and both
622 			 * mp_head and last_head are I/OAT mblks.
623 			 */
624 			ASSERT(mp_head->b_next != NULL);
625 			so->so_rcv_q_last_head->b_prev->b_cont = mp_head;
626 			so->so_rcv_q_last_head->b_prev = mp_head->b_prev;
627 			mp_head->b_prev = NULL;
628 
629 			so->so_rcv_q_last_head->b_next = mp_head->b_next;
630 			mp_head->b_next = NULL;
631 			so->so_rcv_q_last_head = mp_last_head;
632 		} else {
633 #ifdef DEBUG
634 			{
635 				mblk_t *tmp_mblk;
636 				tmp_mblk = mp_head;
637 				while (tmp_mblk != NULL) {
638 					ASSERT(tmp_mblk->b_prev != NULL);
639 					tmp_mblk = tmp_mblk->b_next;
640 				}
641 			}
642 #endif
643 			so->so_rcv_q_last_head->b_next = mp_head;
644 			so->so_rcv_q_last_head = mp_last_head;
645 		}
646 	}
647 }
648 
649 int
650 so_dequeue_msg(struct sonode *so, mblk_t **mctlp, struct uio *uiop,
651     rval_t *rvalp, int flags)
652 {
653 	mblk_t	*mp, *nmp;
654 	mblk_t	*savemp, *savemptail;
655 	mblk_t	*new_msg_head;
656 	mblk_t	*new_msg_last_head;
657 	mblk_t	*last_tail;
658 	boolean_t partial_read;
659 	boolean_t reset_atmark = B_FALSE;
660 	int more = 0;
661 	int error;
662 	ssize_t oobmark;
663 	sodirect_t *sodp = so->so_direct;
664 
665 	partial_read = B_FALSE;
666 	*mctlp = NULL;
667 again:
668 	mutex_enter(&so->so_lock);
669 again1:
670 #ifdef DEBUG
671 	if (so_debug_length) {
672 		ASSERT(so_check_length(so));
673 	}
674 #endif
675 	/*
676 	 * First move messages from the dump area to processing area
677 	 */
678 	if (sodp != NULL) {
679 		/* No need to grab sod_lockp since it pointers to so_lock */
680 		if (sodp->sod_state & SOD_ENABLED) {
681 			ASSERT(sodp->sod_lockp == &so->so_lock);
682 
683 			if (sodp->sod_uioa.uioa_state & UIOA_ALLOC) {
684 				/* nothing to uioamove */
685 				sodp = NULL;
686 			} else if (sodp->sod_uioa.uioa_state & UIOA_INIT) {
687 				sodp->sod_uioa.uioa_state &= UIOA_CLR;
688 				sodp->sod_uioa.uioa_state |= UIOA_ENABLED;
689 				/*
690 				 * try to uioamove() the data that
691 				 * has already queued.
692 				 */
693 				sod_uioa_so_init(so, sodp, uiop);
694 			}
695 		} else {
696 			sodp = NULL;
697 		}
698 	}
699 	new_msg_head = so->so_rcv_head;
700 	new_msg_last_head = so->so_rcv_last_head;
701 	so->so_rcv_head = NULL;
702 	so->so_rcv_last_head = NULL;
703 	oobmark = so->so_oobmark;
704 	/*
705 	 * We can release the lock as there can only be one reader
706 	 */
707 	mutex_exit(&so->so_lock);
708 
709 	if (so->so_state & SS_RCVATMARK) {
710 		reset_atmark = B_TRUE;
711 	}
712 	if (new_msg_head != NULL) {
713 		process_new_message(so, new_msg_head, new_msg_last_head);
714 	}
715 	savemp = savemptail = NULL;
716 	rvalp->r_val1 = 0;
717 	error = 0;
718 	mp = so->so_rcv_q_head;
719 
720 	if (mp != NULL &&
721 	    (so->so_rcv_timer_tid == 0 ||
722 	    so->so_rcv_queued >= so->so_rcv_thresh)) {
723 		partial_read = B_FALSE;
724 
725 		if (flags & MSG_PEEK) {
726 			if ((nmp = dupmsg(mp)) == NULL &&
727 			    (nmp = copymsg(mp)) == NULL) {
728 				size_t size = msgsize(mp);
729 
730 				error = strwaitbuf(size, BPRI_HI);
731 				if (error) {
732 					return (error);
733 				}
734 				goto again;
735 			}
736 			mp = nmp;
737 		} else {
738 			ASSERT(mp->b_prev != NULL);
739 			last_tail = mp->b_prev;
740 			mp->b_prev = NULL;
741 			so->so_rcv_q_head = mp->b_next;
742 			if (so->so_rcv_q_head == NULL) {
743 				so->so_rcv_q_last_head = NULL;
744 			}
745 			mp->b_next = NULL;
746 		}
747 
748 		ASSERT(mctlp != NULL);
749 		/*
750 		 * First process PROTO or PCPROTO blocks, if any.
751 		 */
752 		if (DB_TYPE(mp) != M_DATA) {
753 			*mctlp = mp;
754 			savemp = mp;
755 			savemptail = mp;
756 			ASSERT(DB_TYPE(mp) == M_PROTO ||
757 			    DB_TYPE(mp) == M_PCPROTO);
758 			while (mp->b_cont != NULL &&
759 			    DB_TYPE(mp->b_cont) != M_DATA) {
760 				ASSERT(DB_TYPE(mp->b_cont) == M_PROTO ||
761 				    DB_TYPE(mp->b_cont) == M_PCPROTO);
762 				mp = mp->b_cont;
763 				savemptail = mp;
764 			}
765 			mp = savemptail->b_cont;
766 			savemptail->b_cont = NULL;
767 		}
768 
769 		ASSERT(DB_TYPE(mp) == M_DATA);
770 		/*
771 		 * Now process DATA blocks, if any. Note that for sodirect
772 		 * enabled socket, uio_resid can be 0.
773 		 */
774 		if (uiop->uio_resid >= 0) {
775 			ssize_t copied = 0;
776 
777 			if (sodp != NULL && (DB_FLAGS(mp) & DBLK_UIOA)) {
778 				mutex_enter(sodp->sod_lockp);
779 				ASSERT(uiop == (uio_t *)&sodp->sod_uioa);
780 				copied = sod_uioa_mblk(so, mp);
781 				if (copied > 0)
782 					partial_read = B_TRUE;
783 				mutex_exit(sodp->sod_lockp);
784 				/* mark this mblk as processed */
785 				mp = NULL;
786 			} else {
787 				ssize_t oldresid = uiop->uio_resid;
788 
789 				if (MBLKL(mp) < so_mblk_pull_len) {
790 					if (pullupmsg(mp, -1) == 1) {
791 						last_tail = mp;
792 					}
793 				}
794 				/*
795 				 * Can not read beyond the oobmark
796 				 */
797 				mp = socopyoutuio(mp, uiop,
798 				    oobmark == 0 ? INFPSZ : oobmark, &error);
799 				if (error != 0) {
800 					freemsg(*mctlp);
801 					*mctlp = NULL;
802 					more = 0;
803 					goto done;
804 				}
805 				ASSERT(oldresid >= uiop->uio_resid);
806 				copied = oldresid - uiop->uio_resid;
807 				if (oldresid > uiop->uio_resid)
808 					partial_read = B_TRUE;
809 			}
810 			ASSERT(copied >= 0);
811 			if (copied > 0 && !(flags & MSG_PEEK)) {
812 				mutex_enter(&so->so_lock);
813 				so->so_rcv_queued -= copied;
814 				ASSERT(so->so_oobmark >= 0);
815 				if (so->so_oobmark > 0) {
816 					so->so_oobmark -= copied;
817 					ASSERT(so->so_oobmark >= 0);
818 					if (so->so_oobmark == 0) {
819 						ASSERT(so->so_state &
820 						    SS_OOBPEND);
821 						so->so_oobmark = 0;
822 						so->so_state |= SS_RCVATMARK;
823 					}
824 				}
825 				if (so->so_flowctrld && so->so_rcv_queued <
826 				    so->so_rcvlowat) {
827 					so->so_flowctrld = B_FALSE;
828 					mutex_exit(&so->so_lock);
829 					/*
830 					 * open up flow control
831 					 */
832 					(*so->so_downcalls->sd_clr_flowctrl)
833 					    (so->so_proto_handle);
834 				} else {
835 					mutex_exit(&so->so_lock);
836 				}
837 			}
838 		}
839 		if (mp != NULL) { /* more data blocks in msg */
840 			more |= MOREDATA;
841 			if ((flags & (MSG_PEEK|MSG_TRUNC))) {
842 				if (flags & MSG_TRUNC &&
843 				    ((flags & MSG_PEEK) == 0)) {
844 					mutex_enter(&so->so_lock);
845 					so->so_rcv_queued -= msgdsize(mp);
846 					mutex_exit(&so->so_lock);
847 				}
848 				freemsg(mp);
849 			} else if (partial_read && !somsghasdata(mp)) {
850 				/*
851 				 * Avoid queuing a zero-length tail part of
852 				 * a message. partial_read == 1 indicates that
853 				 * we read some of the message.
854 				 */
855 				freemsg(mp);
856 				more &= ~MOREDATA;
857 			} else {
858 				if (savemp != NULL &&
859 				    (flags & MSG_DUPCTRL)) {
860 					mblk_t *nmp;
861 					/*
862 					 * There should only be non data mblks
863 					 */
864 					ASSERT(DB_TYPE(savemp) != M_DATA &&
865 					    DB_TYPE(savemptail) != M_DATA);
866 try_again:
867 					if ((nmp = dupmsg(savemp)) == NULL &&
868 					    (nmp = copymsg(savemp)) == NULL) {
869 
870 						size_t size = msgsize(savemp);
871 
872 						error = strwaitbuf(size,
873 						    BPRI_HI);
874 						if (error != 0) {
875 							/*
876 							 * In case we
877 							 * cannot copy
878 							 * control data
879 							 * free the remaining
880 							 * data.
881 							 */
882 							freemsg(mp);
883 							goto done;
884 						}
885 						goto try_again;
886 					}
887 
888 					ASSERT(nmp != NULL);
889 					ASSERT(DB_TYPE(nmp) != M_DATA);
890 					savemptail->b_cont = mp;
891 					*mctlp = nmp;
892 					mp = savemp;
893 				}
894 				/*
895 				 * putback mp
896 				 */
897 				so_prepend_msg(so, mp, last_tail);
898 			}
899 		}
900 
901 		/* fast check so_rcv_head if there is more data */
902 		if (partial_read && !(so->so_state & SS_RCVATMARK) &&
903 		    *mctlp == NULL && uiop->uio_resid > 0 &&
904 		    !(flags & MSG_PEEK) && so->so_rcv_head != NULL) {
905 			goto again;
906 		}
907 	} else if (!partial_read) {
908 		mutex_enter(&so->so_lock);
909 		if (so->so_error != 0) {
910 			error = sogeterr(so, !(flags & MSG_PEEK));
911 			mutex_exit(&so->so_lock);
912 			return (error);
913 		}
914 		/*
915 		 * No pending data. Return right away for nonblocking
916 		 * socket, otherwise sleep waiting for data.
917 		 */
918 		if (!(so->so_state & SS_CANTRCVMORE) && uiop->uio_resid > 0) {
919 			if ((uiop->uio_fmode & (FNDELAY|FNONBLOCK)) ||
920 			    (flags & MSG_DONTWAIT)) {
921 				error = EWOULDBLOCK;
922 			} else {
923 				if (so->so_state & (SS_CLOSING |
924 				    SS_FALLBACK_PENDING)) {
925 					mutex_exit(&so->so_lock);
926 					error = EINTR;
927 					goto done;
928 				}
929 
930 				if (so->so_rcv_head != NULL) {
931 					goto again1;
932 				}
933 				so->so_rcv_wakeup = B_TRUE;
934 				so->so_rcv_wanted = uiop->uio_resid;
935 				if (so->so_rcvtimeo == 0) {
936 					/*
937 					 * Zero means disable timeout.
938 					 */
939 					error = cv_wait_sig(&so->so_rcv_cv,
940 					    &so->so_lock);
941 				} else {
942 					clock_t now;
943 					time_to_wait(&now, so->so_rcvtimeo);
944 					error = cv_timedwait_sig(&so->so_rcv_cv,
945 					    &so->so_lock, now);
946 				}
947 				so->so_rcv_wakeup = B_FALSE;
948 				so->so_rcv_wanted = 0;
949 
950 				if (error == 0) {
951 					error = EINTR;
952 				} else if (error == -1) {
953 					error = EAGAIN;
954 				} else {
955 					goto again1;
956 				}
957 			}
958 		}
959 		mutex_exit(&so->so_lock);
960 	}
961 	if (reset_atmark && partial_read && !(flags & MSG_PEEK)) {
962 		/*
963 		 * We are passed the mark, update state
964 		 * 4.3BSD and 4.4BSD clears the mark when peeking across it.
965 		 * The draft Posix socket spec states that the mark should
966 		 * not be cleared when peeking. We follow the latter.
967 		 */
968 		mutex_enter(&so->so_lock);
969 		ASSERT(so_verify_oobstate(so));
970 		so->so_state &= ~(SS_OOBPEND|SS_HAVEOOBDATA|SS_RCVATMARK);
971 		freemsg(so->so_oobmsg);
972 		so->so_oobmsg = NULL;
973 		ASSERT(so_verify_oobstate(so));
974 		mutex_exit(&so->so_lock);
975 	}
976 	ASSERT(so->so_rcv_wakeup == B_FALSE);
977 done:
978 	if (sodp != NULL) {
979 		mutex_enter(sodp->sod_lockp);
980 		if ((sodp->sod_state & SOD_ENABLED) &&
981 		    (sodp->sod_uioa.uioa_state & UIOA_ENABLED)) {
982 			SOD_UIOAFINI(sodp);
983 			if (sodp->sod_uioa.uioa_mbytes > 0) {
984 				ASSERT(so->so_rcv_q_head != NULL ||
985 				    so->so_rcv_head != NULL);
986 				so->so_rcv_queued -= sod_uioa_mblk(so, NULL);
987 				if (error == EWOULDBLOCK)
988 					error = 0;
989 			}
990 		}
991 		mutex_exit(sodp->sod_lockp);
992 	}
993 #ifdef DEBUG
994 	if (so_debug_length) {
995 		mutex_enter(&so->so_lock);
996 		ASSERT(so_check_length(so));
997 		mutex_exit(&so->so_lock);
998 	}
999 #endif
1000 	rvalp->r_val1 = more;
1001 	return (error);
1002 }
1003 
1004 void
1005 so_enqueue_msg(struct sonode *so, mblk_t *mp, size_t msg_size)
1006 {
1007 	ASSERT(MUTEX_HELD(&so->so_lock));
1008 
1009 #ifdef DEBUG
1010 	if (so_debug_length) {
1011 		ASSERT(so_check_length(so));
1012 	}
1013 #endif
1014 	so->so_rcv_queued += msg_size;
1015 
1016 	if (so->so_rcv_head == NULL) {
1017 		ASSERT(so->so_rcv_last_head == NULL);
1018 		so->so_rcv_head = mp;
1019 		so->so_rcv_last_head = mp;
1020 	} else if ((DB_TYPE(mp) == M_DATA &&
1021 	    DB_TYPE(so->so_rcv_last_head) == M_DATA) &&
1022 	    ((DB_FLAGS(mp) & DBLK_UIOA) ==
1023 	    (DB_FLAGS(so->so_rcv_last_head) & DBLK_UIOA))) {
1024 		/* Added to the end */
1025 		ASSERT(so->so_rcv_last_head != NULL);
1026 		ASSERT(so->so_rcv_last_head->b_prev != NULL);
1027 		so->so_rcv_last_head->b_prev->b_cont = mp;
1028 	} else {
1029 		/* Start a new end */
1030 		so->so_rcv_last_head->b_next = mp;
1031 		so->so_rcv_last_head = mp;
1032 	}
1033 	while (mp->b_cont != NULL)
1034 		mp = mp->b_cont;
1035 
1036 	so->so_rcv_last_head->b_prev = mp;
1037 #ifdef DEBUG
1038 	if (so_debug_length) {
1039 		ASSERT(so_check_length(so));
1040 	}
1041 #endif
1042 }
1043 
1044 /*
1045  * Return B_TRUE if there is data in the message, B_FALSE otherwise.
1046  */
1047 boolean_t
1048 somsghasdata(mblk_t *mp)
1049 {
1050 	for (; mp; mp = mp->b_cont)
1051 		if (mp->b_datap->db_type == M_DATA) {
1052 			ASSERT(mp->b_wptr >= mp->b_rptr);
1053 			if (mp->b_wptr > mp->b_rptr)
1054 				return (B_TRUE);
1055 		}
1056 	return (B_FALSE);
1057 }
1058 
1059 /*
1060  * Flush the read side of sockfs.
1061  *
1062  * The caller must be sure that a reader is not already active when the
1063  * buffer is being flushed.
1064  */
1065 void
1066 so_rcv_flush(struct sonode *so)
1067 {
1068 	mblk_t  *mp;
1069 
1070 	ASSERT(MUTEX_HELD(&so->so_lock));
1071 
1072 	if (so->so_oobmsg != NULL) {
1073 		freemsg(so->so_oobmsg);
1074 		so->so_oobmsg = NULL;
1075 		so->so_oobmark = 0;
1076 		so->so_state &=
1077 		    ~(SS_OOBPEND|SS_HAVEOOBDATA|SS_HADOOBDATA|SS_RCVATMARK);
1078 	}
1079 
1080 	/*
1081 	 * Free messages sitting in the send and recv queue
1082 	 */
1083 	while (so->so_rcv_q_head != NULL) {
1084 		mp = so->so_rcv_q_head;
1085 		so->so_rcv_q_head = mp->b_next;
1086 		mp->b_next = mp->b_prev = NULL;
1087 		freemsg(mp);
1088 	}
1089 	while (so->so_rcv_head != NULL) {
1090 		mp = so->so_rcv_head;
1091 		so->so_rcv_head = mp->b_next;
1092 		mp->b_next = mp->b_prev = NULL;
1093 		freemsg(mp);
1094 	}
1095 	so->so_rcv_queued = 0;
1096 	so->so_rcv_q_head = NULL;
1097 	so->so_rcv_q_last_head = NULL;
1098 	so->so_rcv_head = NULL;
1099 	so->so_rcv_last_head = NULL;
1100 }
1101 
1102 /*
1103  * Handle recv* calls that set MSG_OOB or MSG_OOB together with MSG_PEEK.
1104  */
1105 int
1106 sorecvoob(struct sonode *so, struct nmsghdr *msg, struct uio *uiop, int flags,
1107     boolean_t oob_inline)
1108 {
1109 	mblk_t		*mp, *nmp;
1110 	int		error;
1111 
1112 	dprintso(so, 1, ("sorecvoob(%p, %p, 0x%x)\n", (void *)so, (void *)msg,
1113 	    flags));
1114 
1115 	if (msg != NULL) {
1116 		/*
1117 		 * There is never any oob data with addresses or control since
1118 		 * the T_EXDATA_IND does not carry any options.
1119 		 */
1120 		msg->msg_controllen = 0;
1121 		msg->msg_namelen = 0;
1122 		msg->msg_flags = 0;
1123 	}
1124 
1125 	mutex_enter(&so->so_lock);
1126 	ASSERT(so_verify_oobstate(so));
1127 	if (oob_inline ||
1128 	    (so->so_state & (SS_OOBPEND|SS_HADOOBDATA)) != SS_OOBPEND) {
1129 		dprintso(so, 1, ("sorecvoob: inline or data consumed\n"));
1130 		mutex_exit(&so->so_lock);
1131 		return (EINVAL);
1132 	}
1133 	if (!(so->so_state & SS_HAVEOOBDATA)) {
1134 		dprintso(so, 1, ("sorecvoob: no data yet\n"));
1135 		mutex_exit(&so->so_lock);
1136 		return (EWOULDBLOCK);
1137 	}
1138 	ASSERT(so->so_oobmsg != NULL);
1139 	mp = so->so_oobmsg;
1140 	if (flags & MSG_PEEK) {
1141 		/*
1142 		 * Since recv* can not return ENOBUFS we can not use dupmsg.
1143 		 * Instead we revert to the consolidation private
1144 		 * allocb_wait plus bcopy.
1145 		 */
1146 		mblk_t *mp1;
1147 
1148 		mp1 = allocb_wait(msgdsize(mp), BPRI_MED, STR_NOSIG, NULL);
1149 		ASSERT(mp1);
1150 
1151 		while (mp != NULL) {
1152 			ssize_t size;
1153 
1154 			size = MBLKL(mp);
1155 			bcopy(mp->b_rptr, mp1->b_wptr, size);
1156 			mp1->b_wptr += size;
1157 			ASSERT(mp1->b_wptr <= mp1->b_datap->db_lim);
1158 			mp = mp->b_cont;
1159 		}
1160 		mp = mp1;
1161 	} else {
1162 		/*
1163 		 * Update the state indicating that the data has been consumed.
1164 		 * Keep SS_OOBPEND set until data is consumed past the mark.
1165 		 */
1166 		so->so_oobmsg = NULL;
1167 		so->so_state ^= SS_HAVEOOBDATA|SS_HADOOBDATA;
1168 	}
1169 	ASSERT(so_verify_oobstate(so));
1170 	mutex_exit(&so->so_lock);
1171 
1172 	error = 0;
1173 	nmp = mp;
1174 	while (nmp != NULL && uiop->uio_resid > 0) {
1175 		ssize_t n = MBLKL(nmp);
1176 
1177 		n = MIN(n, uiop->uio_resid);
1178 		if (n > 0)
1179 			error = uiomove(nmp->b_rptr, n,
1180 			    UIO_READ, uiop);
1181 		if (error)
1182 			break;
1183 		nmp = nmp->b_cont;
1184 	}
1185 	ASSERT(mp->b_next == NULL && mp->b_prev == NULL);
1186 	freemsg(mp);
1187 	return (error);
1188 }
1189 
1190 /*
1191  * Allocate and initializ sonode
1192  */
1193 /* ARGSUSED */
1194 struct sonode *
1195 socket_sonode_create(struct sockparams *sp, int family, int type,
1196     int protocol, int version, int sflags, int *errorp, struct cred *cr)
1197 {
1198 	sonode_t *so;
1199 	int	kmflags;
1200 
1201 	/*
1202 	 * Choose the right set of sonodeops based on the upcall and
1203 	 * down call version that the protocol has provided
1204 	 */
1205 	if (SOCK_UC_VERSION != sp->sp_smod_info->smod_uc_version ||
1206 	    SOCK_DC_VERSION != sp->sp_smod_info->smod_dc_version) {
1207 		/*
1208 		 * mismatch
1209 		 */
1210 #ifdef DEBUG
1211 		cmn_err(CE_CONT, "protocol and socket module version mismatch");
1212 #endif
1213 		*errorp = EINVAL;
1214 		return (NULL);
1215 	}
1216 
1217 	kmflags = (sflags & SOCKET_NOSLEEP) ? KM_NOSLEEP : KM_SLEEP;
1218 
1219 	so = kmem_cache_alloc(socket_cache, kmflags);
1220 	if (so == NULL) {
1221 		*errorp = ENOMEM;
1222 		return (NULL);
1223 	}
1224 
1225 	sonode_init(so, sp, family, type, protocol, &so_sonodeops);
1226 
1227 	if (version == SOV_DEFAULT)
1228 		version = so_default_version;
1229 
1230 	so->so_version = (short)version;
1231 
1232 	/*
1233 	 * set the default values to be INFPSZ
1234 	 * if a protocol desires it can change the value later
1235 	 */
1236 	so->so_proto_props.sopp_rxhiwat = SOCKET_RECVHIWATER;
1237 	so->so_proto_props.sopp_rxlowat = SOCKET_RECVLOWATER;
1238 	so->so_proto_props.sopp_maxpsz = INFPSZ;
1239 	so->so_proto_props.sopp_maxblk = INFPSZ;
1240 
1241 	return (so);
1242 }
1243 
1244 int
1245 socket_init_common(struct sonode *so, struct sonode *pso, int flags, cred_t *cr)
1246 {
1247 	int error = 0;
1248 
1249 	if (pso != NULL) {
1250 		/*
1251 		 * We have a passive open, so inherit basic state from
1252 		 * the parent (listener).
1253 		 *
1254 		 * No need to grab the new sonode's lock, since there is no
1255 		 * one that can have a reference to it.
1256 		 */
1257 		mutex_enter(&pso->so_lock);
1258 
1259 		so->so_state |= SS_ISCONNECTED | (pso->so_state & SS_ASYNC);
1260 		so->so_pgrp = pso->so_pgrp;
1261 		so->so_rcvtimeo = pso->so_rcvtimeo;
1262 		so->so_sndtimeo = pso->so_sndtimeo;
1263 		so->so_xpg_rcvbuf = pso->so_xpg_rcvbuf;
1264 		/*
1265 		 * Make note of the socket level options. TCP and IP level
1266 		 * options are already inherited. We could do all this after
1267 		 * accept is successful but doing it here simplifies code and
1268 		 * no harm done for error case.
1269 		 */
1270 		so->so_options = pso->so_options & (SO_DEBUG|SO_REUSEADDR|
1271 		    SO_KEEPALIVE|SO_DONTROUTE|SO_BROADCAST|SO_USELOOPBACK|
1272 		    SO_OOBINLINE|SO_DGRAM_ERRIND|SO_LINGER);
1273 		so->so_proto_props = pso->so_proto_props;
1274 		so->so_mode = pso->so_mode;
1275 		so->so_pollev = pso->so_pollev & SO_POLLEV_ALWAYS;
1276 
1277 		mutex_exit(&pso->so_lock);
1278 
1279 		if (uioasync.enabled) {
1280 			sod_sock_init(so, NULL, NULL, NULL, &so->so_lock);
1281 		}
1282 		return (0);
1283 	} else {
1284 		struct sockparams *sp = so->so_sockparams;
1285 		sock_upcalls_t *upcalls_to_use;
1286 
1287 		/*
1288 		 * Based on the version number select the right upcalls to
1289 		 * pass down. Currently we only have one version so choose
1290 		 * default
1291 		 */
1292 		upcalls_to_use = &so_upcalls;
1293 
1294 		/* active open, so create a lower handle */
1295 		so->so_proto_handle =
1296 		    sp->sp_smod_info->smod_proto_create_func(so->so_family,
1297 		    so->so_type, so->so_protocol, &so->so_downcalls,
1298 		    &so->so_mode, &error, flags, cr);
1299 
1300 		if (so->so_proto_handle == NULL) {
1301 			ASSERT(error != 0);
1302 			/*
1303 			 * To be safe; if a lower handle cannot be created, and
1304 			 * the proto does not give a reason why, assume there
1305 			 * was a lack of memory.
1306 			 */
1307 			return ((error == 0) ? ENOMEM : error);
1308 		}
1309 		ASSERT(so->so_downcalls != NULL);
1310 		ASSERT(so->so_downcalls->sd_send != NULL ||
1311 		    so->so_downcalls->sd_send_uio != NULL);
1312 		if (so->so_downcalls->sd_recv_uio != NULL) {
1313 			ASSERT(so->so_downcalls->sd_poll != NULL);
1314 			so->so_pollev |= SO_POLLEV_ALWAYS;
1315 		}
1316 
1317 		(*so->so_downcalls->sd_activate)(so->so_proto_handle,
1318 		    (sock_upper_handle_t)so, upcalls_to_use, 0, cr);
1319 
1320 		/* Wildcard */
1321 
1322 		/*
1323 		 * FIXME No need for this, the protocol can deal with it in
1324 		 * sd_create(). Should update ICMP.
1325 		 */
1326 		if (so->so_protocol != so->so_sockparams->sp_protocol) {
1327 			int protocol = so->so_protocol;
1328 			int error;
1329 			/*
1330 			 * Issue SO_PROTOTYPE setsockopt.
1331 			 */
1332 			error = socket_setsockopt(so, SOL_SOCKET, SO_PROTOTYPE,
1333 			    &protocol, (t_uscalar_t)sizeof (protocol), cr);
1334 			if (error) {
1335 				(void) (*so->so_downcalls->sd_close)
1336 				    (so->so_proto_handle, 0, cr);
1337 
1338 				mutex_enter(&so->so_lock);
1339 				so_rcv_flush(so);
1340 				mutex_exit(&so->so_lock);
1341 				/*
1342 				 * Setsockopt often fails with ENOPROTOOPT but
1343 				 * socket() should fail with
1344 				 * EPROTONOSUPPORT/EPROTOTYPE.
1345 				 */
1346 				return (EPROTONOSUPPORT);
1347 			}
1348 		}
1349 		return (0);
1350 	}
1351 }
1352 
1353 /*
1354  * int socket_ioctl_common(struct sonode *so, int cmd, intptr_t arg, int mode,
1355  *         struct cred *cr, int32_t *rvalp)
1356  *
1357  * Handle ioctls that manipulate basic socket state; non-blocking,
1358  * async, etc.
1359  *
1360  * Returns:
1361  *   < 0  - ioctl was not handle
1362  *  >= 0  - ioctl was handled, if > 0, then it is an errno
1363  *
1364  * Notes:
1365  *   Assumes the standard receive buffer is used to obtain info for
1366  *   NREAD.
1367  */
1368 /* ARGSUSED */
1369 int
1370 socket_ioctl_common(struct sonode *so, int cmd, intptr_t arg, int mode,
1371     struct cred *cr, int32_t *rvalp)
1372 {
1373 	switch (cmd) {
1374 	case SIOCSQPTR:
1375 		/*
1376 		 * SIOCSQPTR is valid only when helper stream is created
1377 		 * by the protocol.
1378 		 */
1379 
1380 		return (EOPNOTSUPP);
1381 	case FIONBIO: {
1382 		int32_t value;
1383 
1384 		if (so_copyin((void *)arg, &value, sizeof (int32_t),
1385 		    (mode & (int)FKIOCTL)))
1386 			return (EFAULT);
1387 
1388 		mutex_enter(&so->so_lock);
1389 		if (value) {
1390 			so->so_state |= SS_NDELAY;
1391 		} else {
1392 			so->so_state &= ~SS_NDELAY;
1393 		}
1394 		mutex_exit(&so->so_lock);
1395 		return (0);
1396 	}
1397 	case FIOASYNC: {
1398 		int32_t value;
1399 
1400 		if (so_copyin((void *)arg, &value, sizeof (int32_t),
1401 		    (mode & (int)FKIOCTL)))
1402 			return (EFAULT);
1403 
1404 		mutex_enter(&so->so_lock);
1405 
1406 		if (value) {
1407 			/* Turn on SIGIO */
1408 			so->so_state |= SS_ASYNC;
1409 		} else {
1410 			/* Turn off SIGIO */
1411 			so->so_state &= ~SS_ASYNC;
1412 		}
1413 		mutex_exit(&so->so_lock);
1414 
1415 		return (0);
1416 	}
1417 
1418 	case SIOCSPGRP:
1419 	case FIOSETOWN: {
1420 		int error;
1421 		pid_t pid;
1422 
1423 		if (so_copyin((void *)arg, &pid, sizeof (pid_t),
1424 		    (mode & (int)FKIOCTL)))
1425 			return (EFAULT);
1426 
1427 		mutex_enter(&so->so_lock);
1428 		error = (pid != so->so_pgrp) ? socket_chgpgrp(so, pid) : 0;
1429 		mutex_exit(&so->so_lock);
1430 		return (error);
1431 	}
1432 	case SIOCGPGRP:
1433 	case FIOGETOWN:
1434 		if (so_copyout(&so->so_pgrp, (void *)arg,
1435 		    sizeof (pid_t), (mode & (int)FKIOCTL)))
1436 			return (EFAULT);
1437 
1438 		return (0);
1439 	case SIOCATMARK: {
1440 		int retval;
1441 
1442 		/*
1443 		 * Only protocols that support urgent data can handle ATMARK.
1444 		 */
1445 		if ((so->so_mode & SM_EXDATA) == 0)
1446 			return (EINVAL);
1447 
1448 		/*
1449 		 * If the protocol is maintaining its own buffer, then the
1450 		 * request must be passed down.
1451 		 */
1452 		if (so->so_downcalls->sd_recv_uio != NULL)
1453 			return (-1);
1454 
1455 		retval = (so->so_state & SS_RCVATMARK) != 0;
1456 
1457 		if (so_copyout(&retval, (void *)arg, sizeof (int),
1458 		    (mode & (int)FKIOCTL))) {
1459 			return (EFAULT);
1460 		}
1461 		return (0);
1462 	}
1463 
1464 	case FIONREAD: {
1465 		int retval;
1466 
1467 		/*
1468 		 * If the protocol is maintaining its own buffer, then the
1469 		 * request must be passed down.
1470 		 */
1471 		if (so->so_downcalls->sd_recv_uio != NULL)
1472 			return (-1);
1473 
1474 		retval = MIN(so->so_rcv_queued, INT_MAX);
1475 
1476 		if (so_copyout(&retval, (void *)arg,
1477 		    sizeof (retval), (mode & (int)FKIOCTL))) {
1478 			return (EFAULT);
1479 		}
1480 		return (0);
1481 	}
1482 
1483 	case _I_GETPEERCRED: {
1484 		int error = 0;
1485 
1486 		if ((mode & FKIOCTL) == 0)
1487 			return (EINVAL);
1488 
1489 		mutex_enter(&so->so_lock);
1490 		if ((so->so_mode & SM_CONNREQUIRED) == 0) {
1491 			error = ENOTSUP;
1492 		} else if ((so->so_state & SS_ISCONNECTED) == 0) {
1493 			error = ENOTCONN;
1494 		} else if (so->so_peercred != NULL) {
1495 			k_peercred_t *kp = (k_peercred_t *)arg;
1496 			kp->pc_cr = so->so_peercred;
1497 			kp->pc_cpid = so->so_cpid;
1498 			crhold(so->so_peercred);
1499 		} else {
1500 			error = EINVAL;
1501 		}
1502 		mutex_exit(&so->so_lock);
1503 		return (error);
1504 	}
1505 	default:
1506 		return (-1);
1507 	}
1508 }
1509 
1510 /*
1511  * Process STREAMS related ioctls. If a I_PUSH/POP operation is specified
1512  * then the socket will fall back to TPI.
1513  *
1514  * Returns:
1515  *   < 0  - ioctl was not handle
1516  *  >= 0  - ioctl was handled, if > 0, then it is an errno
1517  */
1518 int
1519 socket_strioc_common(struct sonode *so, int cmd, intptr_t arg, int mode,
1520     struct cred *cr, int32_t *rvalp)
1521 {
1522 	switch (cmd) {
1523 	case _I_INSERT:
1524 	case _I_REMOVE:
1525 	case I_FIND:
1526 	case I_LIST:
1527 		return (EOPNOTSUPP);
1528 
1529 	case I_PUSH:
1530 	case I_POP: {
1531 		int retval;
1532 
1533 		if ((retval = so_tpi_fallback(so, cr)) == 0) {
1534 			/* Reissue the ioctl */
1535 			ASSERT(so->so_rcv_q_head == NULL);
1536 			return (SOP_IOCTL(so, cmd, arg, mode, cr, rvalp));
1537 		}
1538 		return (retval);
1539 	}
1540 	case I_LOOK:
1541 		if (so_copyout("sockmod", (void *)arg, strlen("sockmod") + 1,
1542 		    (mode & (int)FKIOCTL))) {
1543 			return (EFAULT);
1544 		}
1545 		return (0);
1546 	default:
1547 		return (-1);
1548 	}
1549 }
1550 
1551 int
1552 socket_getopt_common(struct sonode *so, int level, int option_name,
1553     void *optval, socklen_t *optlenp, int flags)
1554 {
1555 	if (level != SOL_SOCKET)
1556 		return (-1);
1557 
1558 	switch (option_name) {
1559 	case SO_ERROR:
1560 	case SO_DOMAIN:
1561 	case SO_TYPE:
1562 	case SO_ACCEPTCONN: {
1563 		int32_t value;
1564 		socklen_t optlen = *optlenp;
1565 
1566 		if (optlen < (t_uscalar_t)sizeof (int32_t)) {
1567 			return (EINVAL);
1568 		}
1569 
1570 		switch (option_name) {
1571 		case SO_ERROR:
1572 			mutex_enter(&so->so_lock);
1573 			value = sogeterr(so, B_TRUE);
1574 			mutex_exit(&so->so_lock);
1575 			break;
1576 		case SO_DOMAIN:
1577 			value = so->so_family;
1578 			break;
1579 		case SO_TYPE:
1580 			value = so->so_type;
1581 			break;
1582 		case SO_ACCEPTCONN:
1583 			if (so->so_state & SS_ACCEPTCONN)
1584 				value = SO_ACCEPTCONN;
1585 			else
1586 				value = 0;
1587 			break;
1588 		}
1589 
1590 		bcopy(&value, optval, sizeof (value));
1591 		*optlenp = sizeof (value);
1592 
1593 		return (0);
1594 	}
1595 	case SO_SNDTIMEO:
1596 	case SO_RCVTIMEO: {
1597 		clock_t value;
1598 		socklen_t optlen = *optlenp;
1599 
1600 		if (get_udatamodel() == DATAMODEL_NONE ||
1601 		    get_udatamodel() == DATAMODEL_NATIVE) {
1602 			if (optlen < sizeof (struct timeval))
1603 				return (EINVAL);
1604 		} else {
1605 			if (optlen < sizeof (struct timeval32))
1606 				return (EINVAL);
1607 		}
1608 		if (option_name == SO_RCVTIMEO)
1609 			value = drv_hztousec(so->so_rcvtimeo);
1610 		else
1611 			value = drv_hztousec(so->so_sndtimeo);
1612 
1613 		if (get_udatamodel() == DATAMODEL_NONE ||
1614 		    get_udatamodel() == DATAMODEL_NATIVE) {
1615 			((struct timeval *)(optval))->tv_sec =
1616 			    value / (1000 * 1000);
1617 			((struct timeval *)(optval))->tv_usec =
1618 			    value % (1000 * 1000);
1619 			*optlenp = sizeof (struct timeval);
1620 		} else {
1621 			((struct timeval32 *)(optval))->tv_sec =
1622 			    value / (1000 * 1000);
1623 			((struct timeval32 *)(optval))->tv_usec =
1624 			    value % (1000 * 1000);
1625 			*optlenp = sizeof (struct timeval32);
1626 		}
1627 		return (0);
1628 	}
1629 	case SO_DEBUG:
1630 	case SO_REUSEADDR:
1631 	case SO_KEEPALIVE:
1632 	case SO_DONTROUTE:
1633 	case SO_BROADCAST:
1634 	case SO_USELOOPBACK:
1635 	case SO_OOBINLINE:
1636 	case SO_SNDBUF:
1637 #ifdef notyet
1638 	case SO_SNDLOWAT:
1639 	case SO_RCVLOWAT:
1640 #endif /* notyet */
1641 	case SO_DGRAM_ERRIND: {
1642 		socklen_t optlen = *optlenp;
1643 
1644 		if (optlen < (t_uscalar_t)sizeof (int32_t))
1645 			return (EINVAL);
1646 		break;
1647 	}
1648 	case SO_RCVBUF: {
1649 		socklen_t optlen = *optlenp;
1650 
1651 		if (optlen < (t_uscalar_t)sizeof (int32_t))
1652 			return (EINVAL);
1653 
1654 		if ((flags & _SOGETSOCKOPT_XPG4_2) && so->so_xpg_rcvbuf != 0) {
1655 			/*
1656 			 * XXX If SO_RCVBUF has been set and this is an
1657 			 * XPG 4.2 application then do not ask the transport
1658 			 * since the transport might adjust the value and not
1659 			 * return exactly what was set by the application.
1660 			 * For non-XPG 4.2 application we return the value
1661 			 * that the transport is actually using.
1662 			 */
1663 			*(int32_t *)optval = so->so_xpg_rcvbuf;
1664 			*optlenp = sizeof (so->so_xpg_rcvbuf);
1665 			return (0);
1666 		}
1667 		/*
1668 		 * If the option has not been set then get a default
1669 		 * value from the transport.
1670 		 */
1671 		break;
1672 	}
1673 	case SO_LINGER: {
1674 		socklen_t optlen = *optlenp;
1675 
1676 		if (optlen < (t_uscalar_t)sizeof (struct linger))
1677 			return (EINVAL);
1678 		break;
1679 	}
1680 	case SO_SND_BUFINFO: {
1681 		socklen_t optlen = *optlenp;
1682 
1683 		if (optlen < (t_uscalar_t)sizeof (struct so_snd_bufinfo))
1684 			return (EINVAL);
1685 		((struct so_snd_bufinfo *)(optval))->sbi_wroff =
1686 		    (so->so_proto_props).sopp_wroff;
1687 		((struct so_snd_bufinfo *)(optval))->sbi_maxblk =
1688 		    (so->so_proto_props).sopp_maxblk;
1689 		((struct so_snd_bufinfo *)(optval))->sbi_maxpsz =
1690 		    (so->so_proto_props).sopp_maxpsz;
1691 		((struct so_snd_bufinfo *)(optval))->sbi_tail =
1692 		    (so->so_proto_props).sopp_tail;
1693 		*optlenp = sizeof (struct so_snd_bufinfo);
1694 		return (0);
1695 	}
1696 	default:
1697 		break;
1698 	}
1699 
1700 	/* Unknown Option */
1701 	return (-1);
1702 }
1703 
1704 void
1705 socket_sonode_destroy(struct sonode *so)
1706 {
1707 	sonode_fini(so);
1708 	kmem_cache_free(socket_cache, so);
1709 }
1710 
1711 int
1712 so_zcopy_wait(struct sonode *so)
1713 {
1714 	int error = 0;
1715 
1716 	mutex_enter(&so->so_lock);
1717 	while (!(so->so_copyflag & STZCNOTIFY)) {
1718 		if (so->so_state & SS_CLOSING) {
1719 			mutex_exit(&so->so_lock);
1720 			return (EINTR);
1721 		}
1722 		if (cv_wait_sig(&so->so_copy_cv, &so->so_lock) == 0) {
1723 			error = EINTR;
1724 			break;
1725 		}
1726 	}
1727 	so->so_copyflag &= ~STZCNOTIFY;
1728 	mutex_exit(&so->so_lock);
1729 	return (error);
1730 }
1731 
1732 void
1733 so_timer_callback(void *arg)
1734 {
1735 	struct sonode *so = (struct sonode *)arg;
1736 
1737 	mutex_enter(&so->so_lock);
1738 
1739 	so->so_rcv_timer_tid = 0;
1740 	if (so->so_rcv_queued > 0) {
1741 		so_notify_data(so, so->so_rcv_queued);
1742 	} else {
1743 		mutex_exit(&so->so_lock);
1744 	}
1745 }
1746 
1747 #ifdef DEBUG
1748 /*
1749  * Verify that the length stored in so_rcv_queued and the length of data blocks
1750  * queued is same.
1751  */
1752 static boolean_t
1753 so_check_length(sonode_t *so)
1754 {
1755 	mblk_t *mp = so->so_rcv_q_head;
1756 	int len = 0;
1757 
1758 	ASSERT(MUTEX_HELD(&so->so_lock));
1759 
1760 	if (mp != NULL) {
1761 		len = msgdsize(mp);
1762 		while ((mp = mp->b_next) != NULL)
1763 			len += msgdsize(mp);
1764 	}
1765 	mp = so->so_rcv_head;
1766 	if (mp != NULL) {
1767 		len += msgdsize(mp);
1768 		while ((mp = mp->b_next) != NULL)
1769 			len += msgdsize(mp);
1770 	}
1771 	return ((len == so->so_rcv_queued) ? B_TRUE : B_FALSE);
1772 }
1773 #endif
1774 
1775 int
1776 so_get_mod_version(struct sockparams *sp)
1777 {
1778 	ASSERT(sp != NULL && sp->sp_smod_info != NULL);
1779 	return (sp->sp_smod_info->smod_version);
1780 }
1781 
1782 /*
1783  * so_start_fallback()
1784  *
1785  * Block new socket operations from coming in, and wait for active operations
1786  * to complete. Threads that are sleeping will be woken up so they can get
1787  * out of the way.
1788  *
1789  * The caller must be a reader on so_fallback_rwlock.
1790  */
1791 static boolean_t
1792 so_start_fallback(struct sonode *so)
1793 {
1794 	ASSERT(RW_READ_HELD(&so->so_fallback_rwlock));
1795 
1796 	mutex_enter(&so->so_lock);
1797 	if (so->so_state & SS_FALLBACK_PENDING) {
1798 		mutex_exit(&so->so_lock);
1799 		return (B_FALSE);
1800 	}
1801 	so->so_state |= SS_FALLBACK_PENDING;
1802 	/*
1803 	 * Poke all threads that might be sleeping. Any operation that comes
1804 	 * in after the cv_broadcast will observe the fallback pending flag
1805 	 * which cause the call to return where it would normally sleep.
1806 	 */
1807 	cv_broadcast(&so->so_state_cv);		/* threads in connect() */
1808 	cv_broadcast(&so->so_rcv_cv);		/* threads in recvmsg() */
1809 	cv_broadcast(&so->so_snd_cv);		/* threads in sendmsg() */
1810 	mutex_enter(&so->so_acceptq_lock);
1811 	cv_broadcast(&so->so_acceptq_cv);	/* threads in accept() */
1812 	mutex_exit(&so->so_acceptq_lock);
1813 	mutex_exit(&so->so_lock);
1814 
1815 	/*
1816 	 * The main reason for the rw_tryupgrade call is to provide
1817 	 * observability during the fallback process. We want to
1818 	 * be able to see if there are pending operations.
1819 	 */
1820 	if (rw_tryupgrade(&so->so_fallback_rwlock) == 0) {
1821 		/*
1822 		 * It is safe to drop and reaquire the fallback lock, because
1823 		 * we are guaranteed that another fallback cannot take place.
1824 		 */
1825 		rw_exit(&so->so_fallback_rwlock);
1826 		DTRACE_PROBE1(pending__ops__wait, (struct sonode *), so);
1827 		rw_enter(&so->so_fallback_rwlock, RW_WRITER);
1828 		DTRACE_PROBE1(pending__ops__complete, (struct sonode *), so);
1829 	}
1830 
1831 	return (B_TRUE);
1832 }
1833 
1834 /*
1835  * so_end_fallback()
1836  *
1837  * Allow socket opertions back in.
1838  *
1839  * The caller must be a writer on so_fallback_rwlock.
1840  */
1841 static void
1842 so_end_fallback(struct sonode *so)
1843 {
1844 	ASSERT(RW_ISWRITER(&so->so_fallback_rwlock));
1845 
1846 	mutex_enter(&so->so_lock);
1847 	so->so_state &= ~SS_FALLBACK_PENDING;
1848 	mutex_exit(&so->so_lock);
1849 
1850 	rw_downgrade(&so->so_fallback_rwlock);
1851 }
1852 
1853 /*
1854  * so_quiesced_cb()
1855  *
1856  * Callback passed to the protocol during fallback. It is called once
1857  * the endpoint is quiescent.
1858  *
1859  * No requests from the user, no notifications from the protocol, so it
1860  * is safe to synchronize the state. Data can also be moved without
1861  * risk for reordering.
1862  *
1863  * NOTE: urgent data is dropped on the floor.
1864  *
1865  * We do not need to hold so_lock, since there can be only one thread
1866  * operating on the sonode.
1867  */
1868 static void
1869 so_quiesced_cb(sock_upper_handle_t sock_handle, queue_t *q,
1870     struct T_capability_ack *tcap, struct sockaddr *laddr, socklen_t laddrlen,
1871     struct sockaddr *faddr, socklen_t faddrlen, short opts)
1872 {
1873 	struct sonode *so = (struct sonode *)sock_handle;
1874 
1875 	sotpi_update_state(so, tcap, laddr, laddrlen, faddr, faddrlen, opts);
1876 
1877 	mutex_enter(&so->so_lock);
1878 	SOCKET_TIMER_CANCEL(so);
1879 	mutex_exit(&so->so_lock);
1880 	/*
1881 	 * Move data to the STREAM head.
1882 	 */
1883 	if (so->so_rcv_head != NULL) {
1884 		if (so->so_rcv_q_last_head == NULL)
1885 			so->so_rcv_q_head = so->so_rcv_head;
1886 		else
1887 			so->so_rcv_q_last_head->b_next = so->so_rcv_head;
1888 		so->so_rcv_q_last_head = so->so_rcv_last_head;
1889 	}
1890 
1891 	while (so->so_rcv_q_head != NULL) {
1892 		mblk_t *mp = so->so_rcv_q_head;
1893 		size_t mlen = msgdsize(mp);
1894 
1895 		so->so_rcv_q_head = mp->b_next;
1896 		mp->b_next = NULL;
1897 		mp->b_prev = NULL;
1898 		so->so_rcv_queued -= mlen;
1899 		putnext(q, mp);
1900 	}
1901 	ASSERT(so->so_rcv_queued == 0);
1902 	so->so_rcv_head = NULL;
1903 	so->so_rcv_last_head = NULL;
1904 	so->so_rcv_q_head = NULL;
1905 	so->so_rcv_q_last_head = NULL;
1906 
1907 #ifdef DEBUG
1908 	if (so->so_oobmsg != NULL || so->so_oobmark > 0) {
1909 		cmn_err(CE_NOTE, "losing oob data due to tpi fallback\n");
1910 	}
1911 #endif
1912 	if (so->so_oobmsg != NULL) {
1913 		freemsg(so->so_oobmsg);
1914 		so->so_oobmsg = NULL;
1915 	}
1916 	so->so_oobmark = 0;
1917 
1918 	ASSERT(so->so_rcv_queued == 0);
1919 }
1920 
1921 /*
1922  * so_tpi_fallback()
1923  *
1924  * This is fallback initation routine; things start here.
1925  *
1926  * Basic strategy:
1927  *   o Block new socket operations from coming in
1928  *   o Allocate/initate info needed by TPI
1929  *   o Quiesce the connection, at which point we sync
1930  *     state and move data
1931  *   o Change operations (sonodeops) associated with the socket
1932  *   o Unblock threads waiting for the fallback to finish
1933  */
1934 int
1935 so_tpi_fallback(struct sonode *so, struct cred *cr)
1936 {
1937 	int error;
1938 	queue_t *q;
1939 	struct sockparams *sp;
1940 	struct sockparams *newsp;
1941 	so_proto_fallback_func_t fbfunc;
1942 	boolean_t direct;
1943 
1944 	error = 0;
1945 	sp = so->so_sockparams;
1946 	fbfunc = sp->sp_smod_info->smod_proto_fallback_func;
1947 
1948 	/*
1949 	 * Fallback can only happen if there is a device associated
1950 	 * with the sonode, and the socket module has a fallback function.
1951 	 */
1952 	if (!SOCKPARAMS_HAS_DEVICE(sp) || fbfunc == NULL)
1953 		return (EINVAL);
1954 
1955 	/*
1956 	 * Initiate fallback; upon success we know that no new requests
1957 	 * will come in from the user.
1958 	 */
1959 	if (!so_start_fallback(so))
1960 		return (EAGAIN);
1961 
1962 	newsp = sockparams_hold_ephemeral_bydev(so->so_family, so->so_type,
1963 	    so->so_protocol, so->so_sockparams->sp_sdev_info.sd_devpath,
1964 	    KM_SLEEP, &error);
1965 	if (error != 0)
1966 		goto out;
1967 
1968 	if (so->so_direct != NULL) {
1969 		sodirect_t *sodp = so->so_direct;
1970 		mutex_enter(sodp->sod_lockp);
1971 
1972 		so->so_direct->sod_state &= ~SOD_ENABLED;
1973 		so->so_state &= ~SS_SODIRECT;
1974 		ASSERT(sodp->sod_uioafh == NULL);
1975 		mutex_exit(sodp->sod_lockp);
1976 	}
1977 
1978 	/* Turn sonode into a TPI socket */
1979 	q = sotpi_convert_sonode(so, newsp, &direct, cr);
1980 	if (q == NULL) {
1981 		zcmn_err(getzoneid(), CE_WARN,
1982 		    "Failed to convert socket to TPI. Pid = %d\n",
1983 		    curproc->p_pid);
1984 		SOCKPARAMS_DEC_REF(newsp);
1985 		error = EINVAL;
1986 		goto out;
1987 	}
1988 
1989 	/*
1990 	 * Now tell the protocol to start using TPI. so_quiesced_cb be
1991 	 * called once it's safe to synchronize state.
1992 	 */
1993 	DTRACE_PROBE1(proto__fallback__begin, struct sonode *, so);
1994 	/* FIXME assumes this cannot fail. TCP can fail to enter squeue */
1995 	(*fbfunc)(so->so_proto_handle, q, direct, so_quiesced_cb);
1996 	DTRACE_PROBE1(proto__fallback__end, struct sonode *, so);
1997 
1998 	/*
1999 	 * Free all pending connection indications, i.e., socket_accept() has
2000 	 * not yet pulled the connection of the queue. The transport sent
2001 	 * a T_CONN_IND message for each pending connection to the STREAM head.
2002 	 */
2003 	so_acceptq_flush(so);
2004 
2005 	mutex_enter(&so->so_lock);
2006 	so->so_state |= SS_FALLBACK_COMP;
2007 	mutex_exit(&so->so_lock);
2008 
2009 	/*
2010 	 * Swap the sonode ops. Socket opertations that come in once this
2011 	 * is done will proceed without blocking.
2012 	 */
2013 	so->so_ops = &sotpi_sonodeops;
2014 
2015 	/*
2016 	 * No longer a non streams socket
2017 	 */
2018 	so->so_not_str = B_FALSE;
2019 	/*
2020 	 * Wake up any threads stuck in poll. This is needed since the poll
2021 	 * head changes when the fallback happens (moves from the sonode to
2022 	 * the STREAMS head).
2023 	 */
2024 	pollwakeup(&so->so_poll_list, POLLERR);
2025 out:
2026 	so_end_fallback(so);
2027 
2028 	return (error);
2029 }
2030