xref: /dragonfly/sys/kern/uipc_socket.c (revision 7485684f)
1 /*
2  * Copyright (c) 2004 Jeffrey M. Hsu.  All rights reserved.
3  * Copyright (c) 2004 The DragonFly Project.  All rights reserved.
4  *
5  * This code is derived from software contributed to The DragonFly Project
6  * by Jeffrey M. Hsu.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. Neither the name of The DragonFly Project nor the names of its
17  *    contributors may be used to endorse or promote products derived
18  *    from this software without specific, prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
21  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
22  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
23  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
24  * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
25  * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
26  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
27  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
28  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
29  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
30  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 /*
35  * Copyright (c) 1982, 1986, 1988, 1990, 1993
36  *	The Regents of the University of California.  All rights reserved.
37  *
38  * Redistribution and use in source and binary forms, with or without
39  * modification, are permitted provided that the following conditions
40  * are met:
41  * 1. Redistributions of source code must retain the above copyright
42  *    notice, this list of conditions and the following disclaimer.
43  * 2. Redistributions in binary form must reproduce the above copyright
44  *    notice, this list of conditions and the following disclaimer in the
45  *    documentation and/or other materials provided with the distribution.
46  * 3. Neither the name of the University nor the names of its contributors
47  *    may be used to endorse or promote products derived from this software
48  *    without specific prior written permission.
49  *
50  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
51  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
52  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
53  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
54  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
55  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
56  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
57  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
58  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
59  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
60  * SUCH DAMAGE.
61  *
62  *	@(#)uipc_socket.c	8.3 (Berkeley) 4/15/94
63  * $FreeBSD: src/sys/kern/uipc_socket.c,v 1.68.2.24 2003/11/11 17:18:18 silby Exp $
64  */
65 
66 #include "opt_inet.h"
67 
68 #include <sys/param.h>
69 #include <sys/systm.h>
70 #include <sys/fcntl.h>
71 #include <sys/malloc.h>
72 #include <sys/mbuf.h>
73 #include <sys/domain.h>
74 #include <sys/file.h>			/* for struct knote */
75 #include <sys/kernel.h>
76 #include <sys/event.h>
77 #include <sys/proc.h>
78 #include <sys/protosw.h>
79 #include <sys/socket.h>
80 #include <sys/socketvar.h>
81 #include <sys/socketops.h>
82 #include <sys/resourcevar.h>
83 #include <sys/signalvar.h>
84 #include <sys/sysctl.h>
85 #include <sys/uio.h>
86 #include <sys/jail.h>
87 #include <vm/vm_zone.h>
88 #include <vm/pmap.h>
89 #include <net/netmsg2.h>
90 #include <net/netisr2.h>
91 
92 #include <sys/socketvar2.h>
93 #include <sys/spinlock2.h>
94 
95 #include <machine/limits.h>
96 
97 #ifdef INET
98 extern int tcp_sosend_agglim;
99 extern int tcp_sosend_async;
100 extern int tcp_sosend_jcluster;
101 extern int udp_sosend_async;
102 extern int udp_sosend_prepend;
103 
104 static int	 do_setopt_accept_filter(struct socket *so, struct sockopt *sopt);
105 #endif /* INET */
106 
107 static void 	filt_sordetach(struct knote *kn);
108 static int 	filt_soread(struct knote *kn, long hint);
109 static void 	filt_sowdetach(struct knote *kn);
110 static int	filt_sowrite(struct knote *kn, long hint);
111 static int	filt_solisten(struct knote *kn, long hint);
112 
113 static int	soclose_sync(struct socket *so, int fflag);
114 static void	soclose_fast(struct socket *so);
115 
116 static struct filterops solisten_filtops =
117 	{ FILTEROP_ISFD|FILTEROP_MPSAFE, NULL, filt_sordetach, filt_solisten };
118 static struct filterops soread_filtops =
119 	{ FILTEROP_ISFD|FILTEROP_MPSAFE, NULL, filt_sordetach, filt_soread };
120 static struct filterops sowrite_filtops =
121 	{ FILTEROP_ISFD|FILTEROP_MPSAFE, NULL, filt_sowdetach, filt_sowrite };
122 static struct filterops soexcept_filtops =
123 	{ FILTEROP_ISFD|FILTEROP_MPSAFE, NULL, filt_sordetach, filt_soread };
124 
125 MALLOC_DEFINE(M_SOCKET, "socket", "socket struct");
126 MALLOC_DEFINE(M_SONAME, "soname", "socket name");
127 MALLOC_DEFINE(M_PCB, "pcb", "protocol control block");
128 
129 
130 static int somaxconn = SOMAXCONN;
131 SYSCTL_INT(_kern_ipc, KIPC_SOMAXCONN, somaxconn, CTLFLAG_RW,
132     &somaxconn, 0, "Maximum pending socket connection queue size");
133 
134 static int use_soclose_fast = 1;
135 SYSCTL_INT(_kern_ipc, OID_AUTO, soclose_fast, CTLFLAG_RW,
136     &use_soclose_fast, 0, "Fast socket close");
137 
138 int use_soaccept_pred_fast = 1;
139 SYSCTL_INT(_kern_ipc, OID_AUTO, soaccept_pred_fast, CTLFLAG_RW,
140     &use_soaccept_pred_fast, 0, "Fast socket accept predication");
141 
142 int use_sendfile_async = 1;
143 SYSCTL_INT(_kern_ipc, OID_AUTO, sendfile_async, CTLFLAG_RW,
144     &use_sendfile_async, 0, "sendfile uses asynchronized pru_send");
145 
146 int use_soconnect_async = 1;
147 SYSCTL_INT(_kern_ipc, OID_AUTO, soconnect_async, CTLFLAG_RW,
148     &use_soconnect_async, 0, "soconnect uses asynchronized pru_connect");
149 
150 static int use_socreate_fast = 1;
151 SYSCTL_INT(_kern_ipc, OID_AUTO, socreate_fast, CTLFLAG_RW,
152     &use_socreate_fast, 0, "Fast socket creation");
153 
154 static int soavailconn = 32;
155 SYSCTL_INT(_kern_ipc, OID_AUTO, soavailconn, CTLFLAG_RW,
156     &soavailconn, 0, "Maximum available socket connection queue size");
157 
158 /*
159  * Socket operation routines.
160  * These routines are called by the routines in
161  * sys_socket.c or from a system process, and
162  * implement the semantics of socket operations by
163  * switching out to the protocol specific routines.
164  */
165 
166 /*
167  * Get a socket structure, and initialize it.
168  * Note that it would probably be better to allocate socket
169  * and PCB at the same time, but I'm not convinced that all
170  * the protocols can be easily modified to do this.
171  */
172 struct socket *
173 soalloc(int waitok, struct protosw *pr)
174 {
175 	globaldata_t gd = mycpu;
176 	struct socket *so;
177 	unsigned waitmask;
178 
179 	waitmask = waitok ? M_WAITOK : M_NOWAIT;
180 	so = kmalloc(sizeof(struct socket), M_SOCKET, M_ZERO|waitmask);
181 	if (so) {
182 		/* XXX race condition for reentrant kernel */
183 		so->so_proto = pr;
184 		TAILQ_INIT(&so->so_aiojobq);
185 		TAILQ_INIT(&so->so_rcv.ssb_mlist);
186 		TAILQ_INIT(&so->so_snd.ssb_mlist);
187 		lwkt_token_init(&so->so_rcv.ssb_token, "rcvtok");
188 		lwkt_token_init(&so->so_snd.ssb_token, "sndtok");
189 		spin_init(&so->so_rcvd_spin, "soalloc");
190 		netmsg_init(&so->so_rcvd_msg.base, so, &netisr_adone_rport,
191 		    MSGF_DROPABLE | MSGF_PRIORITY,
192 		    so->so_proto->pr_usrreqs->pru_rcvd);
193 		so->so_rcvd_msg.nm_pru_flags |= PRUR_ASYNC;
194 		so->so_state = SS_NOFDREF;
195 		so->so_refs = 1;
196 		so->so_inum = gd->gd_anoninum++ * ncpus + gd->gd_cpuid + 2;
197 	}
198 	return so;
199 }
200 
201 int
202 socreate(int dom, struct socket **aso, int type,
203 	int proto, struct thread *td)
204 {
205 	struct proc *p = td->td_proc;
206 	struct protosw *prp;
207 	struct socket *so;
208 	struct pru_attach_info ai;
209 	struct prison *pr = p->p_ucred->cr_prison;
210 	int error;
211 
212 	if (proto)
213 		prp = pffindproto(dom, proto, type);
214 	else
215 		prp = pffindtype(dom, type);
216 
217 	if (prp == NULL || prp->pr_usrreqs->pru_attach == 0)
218 		return (EPROTONOSUPPORT);
219 
220 	if (pr && PRISON_CAP_ISSET(pr->pr_caps, PRISON_CAP_NET_UNIXIPROUTE) &&
221 	    prp->pr_domain->dom_family != PF_LOCAL &&
222 	    prp->pr_domain->dom_family != PF_INET &&
223 	    prp->pr_domain->dom_family != PF_INET6 &&
224 	    prp->pr_domain->dom_family != PF_ROUTE) {
225 		return (EPROTONOSUPPORT);
226 	}
227 
228 	if (prp->pr_type != type)
229 		return (EPROTOTYPE);
230 	so = soalloc(p != NULL, prp);
231 	if (so == NULL)
232 		return (ENOBUFS);
233 
234 	/*
235 	 * Callers of socreate() presumably will connect up a descriptor
236 	 * and call soclose() if they cannot.  This represents our so_refs
237 	 * (which should be 1) from soalloc().
238 	 */
239 	soclrstate(so, SS_NOFDREF);
240 
241 	/*
242 	 * Set a default port for protocol processing.  No action will occur
243 	 * on the socket on this port until an inpcb is attached to it and
244 	 * is able to match incoming packets, or until the socket becomes
245 	 * available to userland.
246 	 *
247 	 * We normally default the socket to the protocol thread on cpu 0,
248 	 * if protocol does not provide its own method to initialize the
249 	 * default port.
250 	 *
251 	 * If PR_SYNC_PORT is set (unix domain sockets) there is no protocol
252 	 * thread and all pr_*()/pru_*() calls are executed synchronously.
253 	 */
254 	if (prp->pr_flags & PR_SYNC_PORT)
255 		so->so_port = &netisr_sync_port;
256 	else if (prp->pr_initport != NULL)
257 		so->so_port = prp->pr_initport();
258 	else
259 		so->so_port = netisr_cpuport(0);
260 
261 	TAILQ_INIT(&so->so_incomp);
262 	TAILQ_INIT(&so->so_comp);
263 	so->so_type = type;
264 	so->so_cred = crhold(p->p_ucred);
265 	ai.sb_rlimit = &p->p_rlimit[RLIMIT_SBSIZE];
266 	ai.p_ucred = p->p_ucred;
267 	ai.fd_rdir = p->p_fd->fd_rdir;
268 
269 	/*
270 	 * Auto-sizing of socket buffers is managed by the protocols and
271 	 * the appropriate flags must be set in the pru_attach function.
272 	 */
273 	if (use_socreate_fast && prp->pr_usrreqs->pru_preattach)
274 		error = so_pru_attach_fast(so, proto, &ai);
275 	else
276 		error = so_pru_attach(so, proto, &ai);
277 	if (error) {
278 		sosetstate(so, SS_NOFDREF);
279 		sofree(so);	/* from soalloc */
280 		return error;
281 	}
282 
283 	/*
284 	 * NOTE: Returns referenced socket.
285 	 */
286 	*aso = so;
287 	return (0);
288 }
289 
290 int
291 sobind(struct socket *so, struct sockaddr *nam, struct thread *td)
292 {
293 	int error;
294 
295 	error = so_pru_bind(so, nam, td);
296 	return (error);
297 }
298 
299 static void
300 sodealloc(struct socket *so)
301 {
302 	KKASSERT((so->so_state & (SS_INCOMP | SS_COMP)) == 0);
303 
304 #ifdef INVARIANTS
305 	if (so->so_options & SO_ACCEPTCONN) {
306 		KASSERT(TAILQ_EMPTY(&so->so_comp), ("so_comp is not empty"));
307 		KASSERT(TAILQ_EMPTY(&so->so_incomp),
308 		    ("so_incomp is not empty"));
309 	}
310 #endif
311 
312 	if (so->so_rcv.ssb_hiwat)
313 		(void)chgsbsize(so->so_cred->cr_uidinfo,
314 		    &so->so_rcv.ssb_hiwat, 0, RLIM_INFINITY);
315 	if (so->so_snd.ssb_hiwat)
316 		(void)chgsbsize(so->so_cred->cr_uidinfo,
317 		    &so->so_snd.ssb_hiwat, 0, RLIM_INFINITY);
318 #ifdef INET
319 	/* remove accept filter if present */
320 	if (so->so_accf != NULL)
321 		do_setopt_accept_filter(so, NULL);
322 #endif /* INET */
323 	crfree(so->so_cred);
324 	if (so->so_faddr != NULL)
325 		kfree(so->so_faddr, M_SONAME);
326 	kfree(so, M_SOCKET);
327 }
328 
329 int
330 solisten(struct socket *so, int backlog, struct thread *td)
331 {
332 	if (so->so_state & (SS_ISCONNECTED | SS_ISCONNECTING))
333 		return (EINVAL);
334 
335 	lwkt_gettoken(&so->so_rcv.ssb_token);
336 	if (TAILQ_EMPTY(&so->so_comp))
337 		so->so_options |= SO_ACCEPTCONN;
338 	lwkt_reltoken(&so->so_rcv.ssb_token);
339 	if (backlog < 0 || backlog > somaxconn)
340 		backlog = somaxconn;
341 	so->so_qlimit = backlog;
342 	return so_pru_listen(so, td);
343 }
344 
345 static void
346 soqflush(struct socket *so)
347 {
348 	lwkt_getpooltoken(so);
349 	if (so->so_options & SO_ACCEPTCONN) {
350 		struct socket *sp;
351 
352 		while ((sp = TAILQ_FIRST(&so->so_incomp)) != NULL) {
353 			KKASSERT((sp->so_state & (SS_INCOMP | SS_COMP)) ==
354 			    SS_INCOMP);
355 			TAILQ_REMOVE(&so->so_incomp, sp, so_list);
356 			so->so_incqlen--;
357 			soclrstate(sp, SS_INCOMP);
358 			soabort_async(sp, TRUE);
359 		}
360 		while ((sp = TAILQ_FIRST(&so->so_comp)) != NULL) {
361 			KKASSERT((sp->so_state & (SS_INCOMP | SS_COMP)) ==
362 			    SS_COMP);
363 			TAILQ_REMOVE(&so->so_comp, sp, so_list);
364 			so->so_qlen--;
365 			soclrstate(sp, SS_COMP);
366 			soabort_async(sp, TRUE);
367 		}
368 	}
369 	lwkt_relpooltoken(so);
370 }
371 
372 /*
373  * Destroy a disconnected socket.  This routine is a NOP if entities
374  * still have a reference on the socket:
375  *
376  *	so_pcb -	The protocol stack still has a reference
377  *	SS_NOFDREF -	There is no longer a file pointer reference
378  */
379 void
380 sofree(struct socket *so)
381 {
382 	struct socket *head;
383 
384 	/*
385 	 * This is a bit hackish at the moment.  We need to interlock
386 	 * any accept queue we are on before we potentially lose the
387 	 * last reference to avoid races against a re-reference from
388 	 * someone operating on the queue.
389 	 */
390 	while ((head = so->so_head) != NULL) {
391 		lwkt_getpooltoken(head);
392 		if (so->so_head == head)
393 			break;
394 		lwkt_relpooltoken(head);
395 	}
396 
397 	/*
398 	 * Arbitrage the last free.
399 	 */
400 	KKASSERT(so->so_refs > 0);
401 	if (atomic_fetchadd_int(&so->so_refs, -1) != 1) {
402 		if (head)
403 			lwkt_relpooltoken(head);
404 		return;
405 	}
406 
407 	KKASSERT(so->so_pcb == NULL && (so->so_state & SS_NOFDREF));
408 	KKASSERT((so->so_state & SS_ASSERTINPROG) == 0);
409 
410 	if (head != NULL) {
411 		/*
412 		 * We're done, remove ourselves from the accept queue we are
413 		 * on, if we are on one.
414 		 */
415 		if (so->so_state & SS_INCOMP) {
416 			KKASSERT((so->so_state & (SS_INCOMP | SS_COMP)) ==
417 			    SS_INCOMP);
418 			TAILQ_REMOVE(&head->so_incomp, so, so_list);
419 			head->so_incqlen--;
420 		} else if (so->so_state & SS_COMP) {
421 			/*
422 			 * We must not decommission a socket that's
423 			 * on the accept(2) queue.  If we do, then
424 			 * accept(2) may hang after select(2) indicated
425 			 * that the listening socket was ready.
426 			 */
427 			KKASSERT((so->so_state & (SS_INCOMP | SS_COMP)) ==
428 			    SS_COMP);
429 			lwkt_relpooltoken(head);
430 			return;
431 		} else {
432 			panic("sofree: not queued");
433 		}
434 		soclrstate(so, SS_INCOMP);
435 		so->so_head = NULL;
436 		lwkt_relpooltoken(head);
437 	} else {
438 		/* Flush accept queues, if we are accepting. */
439 		soqflush(so);
440 	}
441 	ssb_release(&so->so_snd, so);
442 	sorflush(so);
443 	sodealloc(so);
444 }
445 
446 /*
447  * Close a socket on last file table reference removal.
448  * Initiate disconnect if connected.
449  * Free socket when disconnect complete.
450  */
451 int
452 soclose(struct socket *so, int fflag)
453 {
454 	int error;
455 
456 	funsetown(&so->so_sigio);
457 	sosetstate(so, SS_ISCLOSING);
458 	if (!use_soclose_fast ||
459 	    (so->so_proto->pr_flags & PR_SYNC_PORT) ||
460 	    ((so->so_state & SS_ISCONNECTED) &&
461 	     (so->so_options & SO_LINGER) &&
462 	     so->so_linger != 0)) {
463 		error = soclose_sync(so, fflag);
464 	} else {
465 		soclose_fast(so);
466 		error = 0;
467 	}
468 	return error;
469 }
470 
471 void
472 sodiscard(struct socket *so)
473 {
474 	if (so->so_state & SS_NOFDREF)
475 		panic("soclose: NOFDREF");
476 	sosetstate(so, SS_NOFDREF);	/* take ref */
477 }
478 
479 /*
480  * Append the completed queue of head to head_inh (inherting listen socket).
481  */
482 void
483 soinherit(struct socket *head, struct socket *head_inh)
484 {
485 	boolean_t do_wakeup = FALSE;
486 
487 	KASSERT(head->so_options & SO_ACCEPTCONN,
488 	    ("head does not accept connection"));
489 	KASSERT(head_inh->so_options & SO_ACCEPTCONN,
490 	    ("head_inh does not accept connection"));
491 
492 	lwkt_getpooltoken(head);
493 	lwkt_getpooltoken(head_inh);
494 
495 	if (head->so_qlen > 0)
496 		do_wakeup = TRUE;
497 
498 	while (!TAILQ_EMPTY(&head->so_comp)) {
499 		struct ucred *old_cr;
500 		struct socket *sp;
501 
502 		sp = TAILQ_FIRST(&head->so_comp);
503 		KKASSERT((sp->so_state & (SS_INCOMP | SS_COMP)) == SS_COMP);
504 
505 		/*
506 		 * Remove this socket from the current listen socket
507 		 * completed queue.
508 		 */
509 		TAILQ_REMOVE(&head->so_comp, sp, so_list);
510 		head->so_qlen--;
511 
512 		/* Save the old ucred for later free. */
513 		old_cr = sp->so_cred;
514 
515 		/*
516 		 * Install this socket to the inheriting listen socket
517 		 * completed queue.
518 		 */
519 		sp->so_cred = crhold(head_inh->so_cred); /* non-blocking */
520 		sp->so_head = head_inh;
521 
522 		TAILQ_INSERT_TAIL(&head_inh->so_comp, sp, so_list);
523 		head_inh->so_qlen++;
524 
525 		/*
526 		 * NOTE:
527 		 * crfree() may block and release the tokens temporarily.
528 		 * However, we are fine here, since the transition is done.
529 		 */
530 		crfree(old_cr);
531 	}
532 
533 	lwkt_relpooltoken(head_inh);
534 	lwkt_relpooltoken(head);
535 
536 	if (do_wakeup) {
537 		/*
538 		 * "New" connections have arrived
539 		 */
540 		sorwakeup(head_inh);
541 		wakeup(&head_inh->so_timeo);
542 	}
543 }
544 
545 static int
546 soclose_sync(struct socket *so, int fflag)
547 {
548 	int error = 0;
549 
550 	if ((so->so_proto->pr_flags & PR_SYNC_PORT) == 0)
551 		so_pru_sync(so); /* unpend async prus */
552 
553 	if (so->so_pcb == NULL)
554 		goto discard;
555 
556 	if (so->so_state & SS_ISCONNECTED) {
557 		if ((so->so_state & SS_ISDISCONNECTING) == 0) {
558 			error = sodisconnect(so);
559 			if (error)
560 				goto drop;
561 		}
562 		if (so->so_options & SO_LINGER) {
563 			if ((so->so_state & SS_ISDISCONNECTING) &&
564 			    (fflag & FNONBLOCK))
565 				goto drop;
566 			while (so->so_state & SS_ISCONNECTED) {
567 				error = tsleep(&so->so_timeo, PCATCH,
568 					       "soclos", so->so_linger * hz);
569 				if (error)
570 					break;
571 			}
572 		}
573 	}
574 drop:
575 	if (so->so_pcb) {
576 		int error2;
577 
578 		error2 = so_pru_detach(so);
579 		if (error2 == EJUSTRETURN) {
580 			/*
581 			 * Protocol will call sodiscard()
582 			 * and sofree() for us.
583 			 */
584 			return error;
585 		}
586 		if (error == 0)
587 			error = error2;
588 	}
589 discard:
590 	sodiscard(so);
591 	sofree(so);		/* dispose of ref */
592 
593 	return (error);
594 }
595 
596 static void
597 soclose_fast_handler(netmsg_t msg)
598 {
599 	struct socket *so = msg->base.nm_so;
600 
601 	if (so->so_pcb == NULL)
602 		goto discard;
603 
604 	if ((so->so_state & SS_ISCONNECTED) &&
605 	    (so->so_state & SS_ISDISCONNECTING) == 0)
606 		so_pru_disconnect_direct(so);
607 
608 	if (so->so_pcb) {
609 		int error;
610 
611 		error = so_pru_detach_direct(so);
612 		if (error == EJUSTRETURN) {
613 			/*
614 			 * Protocol will call sodiscard()
615 			 * and sofree() for us.
616 			 */
617 			return;
618 		}
619 	}
620 discard:
621 	sodiscard(so);
622 	sofree(so);
623 }
624 
625 static void
626 soclose_fast(struct socket *so)
627 {
628 	struct netmsg_base *base = &so->so_clomsg;
629 
630 	netmsg_init(base, so, &netisr_apanic_rport, 0,
631 	    soclose_fast_handler);
632 	if (so->so_port == netisr_curport())
633 		lwkt_sendmsg_oncpu(so->so_port, &base->lmsg);
634 	else
635 		lwkt_sendmsg(so->so_port, &base->lmsg);
636 }
637 
638 /*
639  * Abort and destroy a socket.  Only one abort can be in progress
640  * at any given moment.
641  */
642 void
643 soabort_async(struct socket *so, boolean_t clr_head)
644 {
645 	/*
646 	 * Keep a reference before clearing the so_head
647 	 * to avoid racing socket close in netisr.
648 	 */
649 	soreference(so);
650 	if (clr_head)
651 		so->so_head = NULL;
652 	so_pru_abort_async(so);
653 }
654 
655 void
656 soabort_direct(struct socket *so)
657 {
658 	soreference(so);
659 	so_pru_abort_direct(so);
660 }
661 
662 /*
663  * so is passed in ref'd, which becomes owned by
664  * the cleared SS_NOFDREF flag.
665  */
666 void
667 soaccept_generic(struct socket *so)
668 {
669 	if ((so->so_state & SS_NOFDREF) == 0)
670 		panic("soaccept: !NOFDREF");
671 	soclrstate(so, SS_NOFDREF);	/* owned by lack of SS_NOFDREF */
672 }
673 
674 int
675 soaccept(struct socket *so, struct sockaddr **nam)
676 {
677 	int error;
678 
679 	soaccept_generic(so);
680 	error = so_pru_accept(so, nam);
681 	return (error);
682 }
683 
684 int
685 soconnect(struct socket *so, struct sockaddr *nam, struct thread *td,
686     boolean_t sync)
687 {
688 	int error;
689 
690 	if (so->so_options & SO_ACCEPTCONN)
691 		return (EOPNOTSUPP);
692 	/*
693 	 * If protocol is connection-based, can only connect once.
694 	 * Otherwise, if connected, try to disconnect first.
695 	 * This allows user to disconnect by connecting to, e.g.,
696 	 * a null address.
697 	 */
698 	if (so->so_state & (SS_ISCONNECTED|SS_ISCONNECTING) &&
699 	    ((so->so_proto->pr_flags & PR_CONNREQUIRED) ||
700 	    (error = sodisconnect(so)))) {
701 		error = EISCONN;
702 	} else {
703 		/*
704 		 * Prevent accumulated error from previous connection
705 		 * from biting us.
706 		 */
707 		so->so_error = 0;
708 		if (!sync && so->so_proto->pr_usrreqs->pru_preconnect)
709 			error = so_pru_connect_async(so, nam, td);
710 		else
711 			error = so_pru_connect(so, nam, td);
712 	}
713 	return (error);
714 }
715 
716 int
717 soconnect2(struct socket *so1, struct socket *so2, struct ucred *cred)
718 {
719 	int error;
720 
721 	error = so_pru_connect2(so1, so2, cred);
722 	return (error);
723 }
724 
725 int
726 sodisconnect(struct socket *so)
727 {
728 	int error;
729 
730 	if ((so->so_state & SS_ISCONNECTED) == 0) {
731 		error = ENOTCONN;
732 		goto bad;
733 	}
734 	if (so->so_state & SS_ISDISCONNECTING) {
735 		error = EALREADY;
736 		goto bad;
737 	}
738 	error = so_pru_disconnect(so);
739 bad:
740 	return (error);
741 }
742 
743 #define	SBLOCKWAIT(f)	(((f) & MSG_DONTWAIT) ? M_NOWAIT : M_WAITOK)
744 /*
745  * Send on a socket.
746  * If send must go all at once and message is larger than
747  * send buffering, then hard error.
748  * Lock against other senders.
749  * If must go all at once and not enough room now, then
750  * inform user that this would block and do nothing.
751  * Otherwise, if nonblocking, send as much as possible.
752  * The data to be sent is described by "uio" if nonzero,
753  * otherwise by the mbuf chain "top" (which must be null
754  * if uio is not).  Data provided in mbuf chain must be small
755  * enough to send all at once.
756  *
757  * Returns nonzero on error, timeout or signal; callers
758  * must check for short counts if EINTR/ERESTART are returned.
759  * Data and control buffers are freed on return.
760  */
761 int
762 sosend(struct socket *so, struct sockaddr *addr, struct uio *uio,
763 	struct mbuf *top, struct mbuf *control, int flags,
764 	struct thread *td)
765 {
766 	struct mbuf **mp;
767 	struct mbuf *m;
768 	size_t resid;
769 	int space, len;
770 	int clen = 0, error, dontroute, mlen;
771 	int atomic = sosendallatonce(so) || top;
772 	int pru_flags;
773 
774 	if (uio) {
775 		resid = uio->uio_resid;
776 	} else {
777 		resid = (size_t)top->m_pkthdr.len;
778 #ifdef INVARIANTS
779 		len = 0;
780 		for (m = top; m; m = m->m_next)
781 			len += m->m_len;
782 		KKASSERT(top->m_pkthdr.len == len);
783 #endif
784 	}
785 
786 	/*
787 	 * WARNING!  resid is unsigned, space and len are signed.  space
788 	 * 	     can wind up negative if the sockbuf is overcommitted.
789 	 *
790 	 * Also check to make sure that MSG_EOR isn't used on SOCK_STREAM
791 	 * type sockets since that's an error.
792 	 */
793 	if (so->so_type == SOCK_STREAM && (flags & MSG_EOR)) {
794 		error = EINVAL;
795 		goto out;
796 	}
797 
798 	dontroute =
799 	    (flags & MSG_DONTROUTE) && (so->so_options & SO_DONTROUTE) == 0 &&
800 	    (so->so_proto->pr_flags & PR_ATOMIC);
801 	if (td->td_lwp != NULL)
802 		td->td_lwp->lwp_ru.ru_msgsnd++;
803 	if (control)
804 		clen = control->m_len;
805 #define	gotoerr(errcode)	{ error = errcode; goto release; }
806 
807 restart:
808 	error = ssb_lock(&so->so_snd, SBLOCKWAIT(flags));
809 	if (error)
810 		goto out;
811 
812 	do {
813 		if (so->so_state & SS_CANTSENDMORE)
814 			gotoerr(EPIPE);
815 		if (so->so_error) {
816 			error = so->so_error;
817 			so->so_error = 0;
818 			goto release;
819 		}
820 		if ((so->so_state & SS_ISCONNECTED) == 0) {
821 			/*
822 			 * `sendto' and `sendmsg' is allowed on a connection-
823 			 * based socket if it supports implied connect.
824 			 * Return ENOTCONN if not connected and no address is
825 			 * supplied.
826 			 */
827 			if ((so->so_proto->pr_flags & PR_CONNREQUIRED) &&
828 			    (so->so_proto->pr_flags & PR_IMPLOPCL) == 0) {
829 				if ((so->so_state & SS_ISCONFIRMING) == 0 &&
830 				    !(resid == 0 && clen != 0))
831 					gotoerr(ENOTCONN);
832 			} else if (addr == NULL)
833 			    gotoerr(so->so_proto->pr_flags & PR_CONNREQUIRED ?
834 				   ENOTCONN : EDESTADDRREQ);
835 		}
836 		if ((atomic && resid > so->so_snd.ssb_hiwat) ||
837 		    clen > so->so_snd.ssb_hiwat) {
838 			gotoerr(EMSGSIZE);
839 		}
840 		space = ssb_space(&so->so_snd);
841 		if (flags & MSG_OOB)
842 			space += 1024;
843 		if ((space < 0 || (size_t)space < resid + clen) && uio &&
844 		    (atomic || space < so->so_snd.ssb_lowat || space < clen)) {
845 			if (flags & (MSG_FNONBLOCKING|MSG_DONTWAIT))
846 				gotoerr(EWOULDBLOCK);
847 			ssb_unlock(&so->so_snd);
848 			error = ssb_wait(&so->so_snd);
849 			if (error)
850 				goto out;
851 			goto restart;
852 		}
853 		mp = &top;
854 		space -= clen;
855 		do {
856 		    if (uio == NULL) {
857 			/*
858 			 * Data is prepackaged in "top".
859 			 */
860 			resid = 0;
861 			if (flags & MSG_EOR)
862 				top->m_flags |= M_EOR;
863 		    } else do {
864 			if (resid > INT_MAX)
865 				resid = INT_MAX;
866 			m = m_getl((int)resid, M_WAITOK, MT_DATA,
867 				   top == NULL ? M_PKTHDR : 0, &mlen);
868 			if (top == NULL) {
869 				m->m_pkthdr.len = 0;
870 				m->m_pkthdr.rcvif = NULL;
871 			}
872 			len = imin((int)szmin(mlen, resid), space);
873 			if (resid < MINCLSIZE) {
874 				/*
875 				 * For datagram protocols, leave room
876 				 * for protocol headers in first mbuf.
877 				 */
878 				if (atomic && top == NULL && len < mlen)
879 					MH_ALIGN(m, len);
880 			}
881 			space -= len;
882 			error = uiomove(mtod(m, caddr_t), (size_t)len, uio);
883 			resid = uio->uio_resid;
884 			m->m_len = len;
885 			*mp = m;
886 			top->m_pkthdr.len += len;
887 			if (error)
888 				goto release;
889 			mp = &m->m_next;
890 			if (resid == 0) {
891 				if (flags & MSG_EOR)
892 					top->m_flags |= M_EOR;
893 				break;
894 			}
895 		    } while (space > 0 && atomic);
896 		    if (dontroute)
897 			    so->so_options |= SO_DONTROUTE;
898 		    if (flags & MSG_OOB) {
899 		    	    pru_flags = PRUS_OOB;
900 		    } else if ((flags & MSG_EOF) &&
901 		    	       (so->so_proto->pr_flags & PR_IMPLOPCL) &&
902 			       (resid == 0)) {
903 			    /*
904 			     * If the user set MSG_EOF, the protocol
905 			     * understands this flag and nothing left to
906 			     * send then use PRU_SEND_EOF instead of PRU_SEND.
907 			     */
908 		    	    pru_flags = PRUS_EOF;
909 		    } else if (resid > 0 && space > 0) {
910 			    /* If there is more to send, set PRUS_MORETOCOME */
911 		    	    pru_flags = PRUS_MORETOCOME;
912 		    } else {
913 		    	    pru_flags = 0;
914 		    }
915 		    /*
916 		     * XXX all the SS_CANTSENDMORE checks previously
917 		     * done could be out of date.  We could have recieved
918 		     * a reset packet in an interrupt or maybe we slept
919 		     * while doing page faults in uiomove() etc. We could
920 		     * probably recheck again inside the splnet() protection
921 		     * here, but there are probably other places that this
922 		     * also happens.  We must rethink this.
923 		     */
924 		    error = so_pru_send(so, pru_flags, top, addr, control, td);
925 		    if (dontroute)
926 			    so->so_options &= ~SO_DONTROUTE;
927 		    clen = 0;
928 		    control = NULL;
929 		    top = NULL;
930 		    mp = &top;
931 		    if (error)
932 			    goto release;
933 		} while (resid && space > 0);
934 	} while (resid);
935 
936 release:
937 	ssb_unlock(&so->so_snd);
938 out:
939 	if (top)
940 		m_freem(top);
941 	if (control)
942 		m_freem(control);
943 	return (error);
944 }
945 
946 #ifdef INET
947 /*
948  * A specialization of sosend() for UDP based on protocol-specific knowledge:
949  *   so->so_proto->pr_flags has the PR_ATOMIC field set.  This means that
950  *	sosendallatonce() returns true,
951  *	the "atomic" variable is true,
952  *	and sosendudp() blocks until space is available for the entire send.
953  *   so->so_proto->pr_flags does not have the PR_CONNREQUIRED or
954  *	PR_IMPLOPCL flags set.
955  *   UDP has no out-of-band data.
956  *   UDP has no control data.
957  *   UDP does not support MSG_EOR.
958  */
959 int
960 sosendudp(struct socket *so, struct sockaddr *addr, struct uio *uio,
961 	  struct mbuf *top, struct mbuf *control, int flags, struct thread *td)
962 {
963 	size_t resid;
964 	int error, pru_flags = 0;
965 	int space;
966 
967 	if (td->td_lwp != NULL)
968 		td->td_lwp->lwp_ru.ru_msgsnd++;
969 
970 	KASSERT((uio && !top) || (top && !uio), ("bad arguments to sosendudp"));
971 	resid = uio ? uio->uio_resid : (size_t)top->m_pkthdr.len;
972 
973 restart:
974 	error = ssb_lock(&so->so_snd, SBLOCKWAIT(flags));
975 	if (error)
976 		goto out;
977 
978 	if (so->so_state & SS_CANTSENDMORE)
979 		gotoerr(EPIPE);
980 	if (so->so_error) {
981 		error = so->so_error;
982 		so->so_error = 0;
983 		goto release;
984 	}
985 	if (!(so->so_state & SS_ISCONNECTED) && addr == NULL)
986 		gotoerr(EDESTADDRREQ);
987 	if (resid > so->so_snd.ssb_hiwat)
988 		gotoerr(EMSGSIZE);
989 	space = ssb_space(&so->so_snd);
990 	if (uio && (space < 0 || (size_t)space < resid)) {
991 		if (flags & (MSG_FNONBLOCKING|MSG_DONTWAIT))
992 			gotoerr(EWOULDBLOCK);
993 		ssb_unlock(&so->so_snd);
994 		error = ssb_wait(&so->so_snd);
995 		if (error)
996 			goto out;
997 		goto restart;
998 	}
999 
1000 	if (uio) {
1001 		int hdrlen = max_hdr;
1002 
1003 		/*
1004 		 * We try to optimize out the additional mbuf
1005 		 * allocations in M_PREPEND() on output path, e.g.
1006 		 * - udp_output(), when it tries to prepend protocol
1007 		 *   headers.
1008 		 * - Link layer output function, when it tries to
1009 		 *   prepend link layer header.
1010 		 *
1011 		 * This probably will not benefit any data that will
1012 		 * be fragmented, so this optimization is only performed
1013 		 * when the size of data and max size of protocol+link
1014 		 * headers fit into one mbuf cluster.
1015 		 */
1016 		if (uio->uio_resid > MCLBYTES - hdrlen ||
1017 		    !udp_sosend_prepend) {
1018 			top = m_uiomove(uio);
1019 			if (top == NULL)
1020 				goto release;
1021 		} else {
1022 			int nsize;
1023 
1024 			top = m_getl(uio->uio_resid + hdrlen, M_WAITOK,
1025 			    MT_DATA, M_PKTHDR, &nsize);
1026 			KASSERT(nsize >= uio->uio_resid + hdrlen,
1027 			    ("sosendudp invalid nsize %d, "
1028 			     "resid %zu, hdrlen %d",
1029 			     nsize, uio->uio_resid, hdrlen));
1030 
1031 			top->m_len = uio->uio_resid;
1032 			top->m_pkthdr.len = uio->uio_resid;
1033 			top->m_data += hdrlen;
1034 
1035 			error = uiomove(mtod(top, caddr_t), top->m_len, uio);
1036 			if (error)
1037 				goto out;
1038 		}
1039 	}
1040 
1041 	if (flags & MSG_DONTROUTE)
1042 		pru_flags |= PRUS_DONTROUTE;
1043 
1044 	if (udp_sosend_async && (flags & MSG_SYNC) == 0) {
1045 		so_pru_send_async(so, pru_flags, top, addr, control, td);
1046 		error = 0;
1047 	} else {
1048 		error = so_pru_send(so, pru_flags, top, addr, control, td);
1049 	}
1050 
1051 	/* sent or freed in lower layer */
1052 	control = NULL;
1053 	top = NULL;
1054 
1055 release:
1056 	ssb_unlock(&so->so_snd);
1057 out:
1058 	if (top)
1059 		m_freem(top);
1060 	if (control)
1061 		m_freem(control);
1062 	return (error);
1063 }
1064 
1065 int
1066 sosendtcp(struct socket *so, struct sockaddr *addr, struct uio *uio,
1067 	struct mbuf *top, struct mbuf *control, int flags,
1068 	struct thread *td)
1069 {
1070 	struct mbuf **mp;
1071 	struct mbuf *m;
1072 	size_t resid;
1073 	int space, len;
1074 	int error, mlen;
1075 	int allatonce;
1076 	int pru_flags;
1077 
1078 	if (uio) {
1079 		KKASSERT(top == NULL);
1080 		allatonce = 0;
1081 		resid = uio->uio_resid;
1082 	} else {
1083 		allatonce = 1;
1084 		resid = (size_t)top->m_pkthdr.len;
1085 #ifdef INVARIANTS
1086 		len = 0;
1087 		for (m = top; m; m = m->m_next)
1088 			len += m->m_len;
1089 		KKASSERT(top->m_pkthdr.len == len);
1090 #endif
1091 	}
1092 
1093 	/*
1094 	 * WARNING!  resid is unsigned, space and len are signed.  space
1095 	 * 	     can wind up negative if the sockbuf is overcommitted.
1096 	 *
1097 	 * Also check to make sure that MSG_EOR isn't used on TCP
1098 	 */
1099 	if (flags & MSG_EOR) {
1100 		error = EINVAL;
1101 		goto out;
1102 	}
1103 
1104 	if (control) {
1105 		/* TCP doesn't do control messages (rights, creds, etc) */
1106 		if (control->m_len) {
1107 			error = EINVAL;
1108 			goto out;
1109 		}
1110 		m_freem(control);	/* empty control, just free it */
1111 		control = NULL;
1112 	}
1113 
1114 	if (td->td_lwp != NULL)
1115 		td->td_lwp->lwp_ru.ru_msgsnd++;
1116 
1117 #define	gotoerr(errcode)	{ error = errcode; goto release; }
1118 
1119 restart:
1120 	error = ssb_lock(&so->so_snd, SBLOCKWAIT(flags));
1121 	if (error)
1122 		goto out;
1123 
1124 	do {
1125 		if (so->so_state & SS_CANTSENDMORE)
1126 			gotoerr(EPIPE);
1127 		if (so->so_error) {
1128 			error = so->so_error;
1129 			so->so_error = 0;
1130 			goto release;
1131 		}
1132 		if ((so->so_state & SS_ISCONNECTED) == 0 &&
1133 		    (so->so_state & SS_ISCONFIRMING) == 0)
1134 			gotoerr(ENOTCONN);
1135 		if (allatonce && resid > so->so_snd.ssb_hiwat)
1136 			gotoerr(EMSGSIZE);
1137 
1138 		space = ssb_space_prealloc(&so->so_snd);
1139 		if (flags & MSG_OOB)
1140 			space += 1024;
1141 		if ((space < 0 || (size_t)space < resid) && !allatonce &&
1142 		    space < so->so_snd.ssb_lowat) {
1143 			if (flags & (MSG_FNONBLOCKING|MSG_DONTWAIT))
1144 				gotoerr(EWOULDBLOCK);
1145 			ssb_unlock(&so->so_snd);
1146 			error = ssb_wait(&so->so_snd);
1147 			if (error)
1148 				goto out;
1149 			goto restart;
1150 		}
1151 		mp = &top;
1152 		do {
1153 		    int cnt = 0, async = 0;
1154 
1155 		    if (uio == NULL) {
1156 			/*
1157 			 * Data is prepackaged in "top".
1158 			 */
1159 			resid = 0;
1160 		    } else do {
1161 			if (resid > INT_MAX)
1162 				resid = INT_MAX;
1163 			if (tcp_sosend_jcluster) {
1164 				m = m_getlj((int)resid, M_WAITOK, MT_DATA,
1165 					   top == NULL ? M_PKTHDR : 0, &mlen);
1166 			} else {
1167 				m = m_getl((int)resid, M_WAITOK, MT_DATA,
1168 					   top == NULL ? M_PKTHDR : 0, &mlen);
1169 			}
1170 			if (top == NULL) {
1171 				m->m_pkthdr.len = 0;
1172 				m->m_pkthdr.rcvif = NULL;
1173 			}
1174 			len = imin((int)szmin(mlen, resid), space);
1175 			space -= len;
1176 			error = uiomove(mtod(m, caddr_t), (size_t)len, uio);
1177 			resid = uio->uio_resid;
1178 			m->m_len = len;
1179 			*mp = m;
1180 			top->m_pkthdr.len += len;
1181 			if (error)
1182 				goto release;
1183 			mp = &m->m_next;
1184 			if (resid == 0)
1185 				break;
1186 			++cnt;
1187 		    } while (space > 0 && cnt < tcp_sosend_agglim);
1188 
1189 		    if (tcp_sosend_async)
1190 			    async = 1;
1191 
1192 		    if (flags & MSG_OOB) {
1193 		    	    pru_flags = PRUS_OOB;
1194 			    async = 0;
1195 		    } else if ((flags & MSG_EOF) && resid == 0) {
1196 			    pru_flags = PRUS_EOF;
1197 		    } else if (resid > 0 && space > 0) {
1198 			    /* If there is more to send, set PRUS_MORETOCOME */
1199 		    	    pru_flags = PRUS_MORETOCOME;
1200 			    async = 1;
1201 		    } else {
1202 		    	    pru_flags = 0;
1203 		    }
1204 
1205 		    if (flags & MSG_SYNC)
1206 			    async = 0;
1207 
1208 		    /*
1209 		     * XXX all the SS_CANTSENDMORE checks previously
1210 		     * done could be out of date.  We could have recieved
1211 		     * a reset packet in an interrupt or maybe we slept
1212 		     * while doing page faults in uiomove() etc. We could
1213 		     * probably recheck again inside the splnet() protection
1214 		     * here, but there are probably other places that this
1215 		     * also happens.  We must rethink this.
1216 		     */
1217 		    for (m = top; m; m = m->m_next)
1218 			    ssb_preallocstream(&so->so_snd, m);
1219 		    if (!async) {
1220 			    error = so_pru_send(so, pru_flags, top,
1221 			        NULL, NULL, td);
1222 		    } else {
1223 			    so_pru_send_async(so, pru_flags, top,
1224 			        NULL, NULL, td);
1225 			    error = 0;
1226 		    }
1227 
1228 		    top = NULL;
1229 		    mp = &top;
1230 		    if (error)
1231 			    goto release;
1232 		} while (resid && space > 0);
1233 	} while (resid);
1234 
1235 release:
1236 	ssb_unlock(&so->so_snd);
1237 out:
1238 	if (top)
1239 		m_freem(top);
1240 	if (control)
1241 		m_freem(control);
1242 	return (error);
1243 }
1244 #endif
1245 
1246 /*
1247  * Implement receive operations on a socket.
1248  *
1249  * We depend on the way that records are added to the signalsockbuf
1250  * by sbappend*.  In particular, each record (mbufs linked through m_next)
1251  * must begin with an address if the protocol so specifies,
1252  * followed by an optional mbuf or mbufs containing ancillary data,
1253  * and then zero or more mbufs of data.
1254  *
1255  * Although the signalsockbuf is locked, new data may still be appended.
1256  * A token inside the ssb_lock deals with MP issues and still allows
1257  * the network to access the socket if we block in a uio.
1258  *
1259  * The caller may receive the data as a single mbuf chain by supplying
1260  * sio for use in returning the chain.
1261  */
1262 int
1263 soreceive(struct socket *so, struct sockaddr **psa, struct uio *uio,
1264 	  struct sockbuf *sio, struct mbuf **controlp, int *flagsp)
1265 {
1266 	struct mbuf *m, *n;
1267 	struct mbuf *free_chain = NULL;
1268 	int flags, len, error, offset;
1269 	struct protosw *pr = so->so_proto;
1270 	int moff, type = 0;
1271 	size_t resid, orig_resid;
1272 	boolean_t free_rights = FALSE;
1273 
1274 	if (uio)
1275 		resid = uio->uio_resid;
1276 	else
1277 		resid = (size_t)(sio->sb_climit - sio->sb_cc);
1278 	orig_resid = resid;
1279 
1280 	if (psa)
1281 		*psa = NULL;
1282 	if (controlp)
1283 		*controlp = NULL;
1284 	if (flagsp)
1285 		flags = *flagsp &~ MSG_EOR;
1286 	else
1287 		flags = 0;
1288 	if (flags & MSG_OOB) {
1289 		m = m_get(M_WAITOK, MT_DATA);
1290 		error = so_pru_rcvoob(so, m, flags & MSG_PEEK);
1291 		if (error)
1292 			goto bad;
1293 		if (sio) {
1294 			do {
1295 				sbappend(sio, m);
1296 				KKASSERT(resid >= (size_t)m->m_len);
1297 				resid -= (size_t)m->m_len;
1298 				m = m_free(m);
1299 			} while (resid > 0 && m);
1300 		} else {
1301 			do {
1302 				uio->uio_resid = resid;
1303 				error = uiomove(mtod(m, caddr_t),
1304 						(int)szmin(resid, m->m_len),
1305 						uio);
1306 				resid = uio->uio_resid;
1307 				m = m_free(m);
1308 			} while (uio->uio_resid && error == 0 && m);
1309 		}
1310 bad:
1311 		if (m)
1312 			m_freem(m);
1313 		return (error);
1314 	}
1315 	if ((so->so_state & SS_ISCONFIRMING) && resid)
1316 		so_pru_rcvd(so, 0);
1317 
1318 	/*
1319 	 * The token interlocks against the protocol thread while
1320 	 * ssb_lock is a blocking lock against other userland entities.
1321 	 */
1322 	lwkt_gettoken(&so->so_rcv.ssb_token);
1323 restart:
1324 	error = ssb_lock(&so->so_rcv, SBLOCKWAIT(flags));
1325 	if (error)
1326 		goto done;
1327 
1328 	m = so->so_rcv.ssb_mb;
1329 	/*
1330 	 * If we have less data than requested, block awaiting more
1331 	 * (subject to any timeout) if:
1332 	 *   1. the current count is less than the low water mark, or
1333 	 *   2. MSG_WAITALL is set, and it is possible to do the entire
1334 	 *	receive operation at once if we block (resid <= hiwat).
1335 	 *   3. MSG_DONTWAIT is not set
1336 	 * If MSG_WAITALL is set but resid is larger than the receive buffer,
1337 	 * we have to do the receive in sections, and thus risk returning
1338 	 * a short count if a timeout or signal occurs after we start.
1339 	 */
1340 	if (m == NULL ||
1341 	    (((flags & MSG_DONTWAIT) == 0 &&
1342 	      (size_t)so->so_rcv.ssb_cc < resid) &&
1343 	     (so->so_rcv.ssb_cc < so->so_rcv.ssb_lowat ||
1344 	      ((flags & MSG_WAITALL) &&
1345 	       resid <= (size_t)so->so_rcv.ssb_hiwat)) &&
1346 	     m->m_nextpkt == 0 && (pr->pr_flags & PR_ATOMIC) == 0))
1347 	{
1348 		KASSERT(m != NULL || !so->so_rcv.ssb_cc, ("receive 1"));
1349 		if (so->so_error || so->so_rerror) {
1350 			if (m)
1351 				goto dontblock;
1352 			if (so->so_error)
1353 				error = so->so_error;
1354 			else
1355 				error = so->so_rerror;
1356 			if ((flags & MSG_PEEK) == 0) {
1357 				if (so->so_error)
1358 					so->so_error = 0;
1359 				else
1360 					so->so_rerror = 0;
1361 			}
1362 			goto release;
1363 		}
1364 		if (so->so_state & SS_CANTRCVMORE) {
1365 			if (m)
1366 				goto dontblock;
1367 			else
1368 				goto release;
1369 		}
1370 		for (; m; m = m->m_next) {
1371 			if (m->m_type == MT_OOBDATA  || (m->m_flags & M_EOR)) {
1372 				m = so->so_rcv.ssb_mb;
1373 				goto dontblock;
1374 			}
1375 		}
1376 		if ((so->so_state & (SS_ISCONNECTED|SS_ISCONNECTING)) == 0 &&
1377 		    (pr->pr_flags & PR_CONNREQUIRED)) {
1378 			error = ENOTCONN;
1379 			goto release;
1380 		}
1381 		if (resid == 0)
1382 			goto release;
1383 		if (flags & (MSG_FNONBLOCKING|MSG_DONTWAIT)) {
1384 			error = EWOULDBLOCK;
1385 			goto release;
1386 		}
1387 		ssb_unlock(&so->so_rcv);
1388 		error = ssb_wait(&so->so_rcv);
1389 		if (error)
1390 			goto done;
1391 		goto restart;
1392 	}
1393 dontblock:
1394 	if (uio && uio->uio_td && uio->uio_td->td_proc)
1395 		uio->uio_td->td_lwp->lwp_ru.ru_msgrcv++;
1396 
1397 	/*
1398 	 * note: m should be == sb_mb here.  Cache the next record while
1399 	 * cleaning up.  Note that calling m_free*() will break out critical
1400 	 * section.
1401 	 */
1402 	KKASSERT(m == so->so_rcv.ssb_mb);
1403 
1404 	/*
1405 	 * Skip any address mbufs prepending the record.
1406 	 */
1407 	if (pr->pr_flags & PR_ADDR) {
1408 		KASSERT(m->m_type == MT_SONAME, ("receive 1a"));
1409 		orig_resid = 0;
1410 		if (psa)
1411 			*psa = dup_sockaddr(mtod(m, struct sockaddr *));
1412 		if (flags & MSG_PEEK)
1413 			m = m->m_next;
1414 		else
1415 			m = sbunlinkmbuf(&so->so_rcv.sb, m, &free_chain);
1416 	}
1417 
1418 	/*
1419 	 * Skip any control mbufs prepending the record.
1420 	 */
1421 	while (m && m->m_type == MT_CONTROL && error == 0) {
1422 		if (flags & MSG_PEEK) {
1423 			if (controlp)
1424 				*controlp = m_copym(m, 0, m->m_len, M_NOWAIT);
1425 			m = m->m_next;	/* XXX race */
1426 		} else {
1427 			const struct cmsghdr *cm = mtod(m, struct cmsghdr *);
1428 
1429 			if (controlp) {
1430 				n = sbunlinkmbuf(&so->so_rcv.sb, m, NULL);
1431 				if (pr->pr_domain->dom_externalize &&
1432 				    cm->cmsg_level == SOL_SOCKET &&
1433 				    cm->cmsg_type == SCM_RIGHTS) {
1434 					error = pr->pr_domain->dom_externalize
1435 					    (m, flags);
1436 				}
1437 				*controlp = m;
1438 				m = n;
1439 			} else {
1440 				if (cm->cmsg_level == SOL_SOCKET &&
1441 				    cm->cmsg_type == SCM_RIGHTS)
1442 					free_rights = TRUE;
1443 				m = sbunlinkmbuf(&so->so_rcv.sb, m, &free_chain);
1444 			}
1445 		}
1446 		if (controlp && *controlp) {
1447 			orig_resid = 0;
1448 			controlp = &(*controlp)->m_next;
1449 		}
1450 	}
1451 
1452 	/*
1453 	 * flag OOB data.
1454 	 */
1455 	if (m) {
1456 		type = m->m_type;
1457 		if (type == MT_OOBDATA)
1458 			flags |= MSG_OOB;
1459 	}
1460 
1461 	/*
1462 	 * Copy to the UIO or mbuf return chain (*mp).
1463 	 */
1464 	moff = 0;
1465 	offset = 0;
1466 	while (m && resid > 0 && error == 0) {
1467 		if (m->m_type == MT_OOBDATA) {
1468 			if (type != MT_OOBDATA)
1469 				break;
1470 		} else if (type == MT_OOBDATA) {
1471 			break;
1472 		} else {
1473 			KASSERT(m->m_type == MT_DATA || m->m_type == MT_HEADER,
1474 				("receive 3"));
1475 		}
1476 		soclrstate(so, SS_RCVATMARK);
1477 		len = (resid > INT_MAX) ? INT_MAX : resid;
1478 		if (so->so_oobmark && len > so->so_oobmark - offset)
1479 			len = so->so_oobmark - offset;
1480 		if (len > m->m_len - moff)
1481 			len = m->m_len - moff;
1482 
1483 		/*
1484 		 * Copy out to the UIO or pass the mbufs back to the SIO.
1485 		 * The SIO is dealt with when we eat the mbuf, but deal
1486 		 * with the resid here either way.
1487 		 */
1488 		if (uio) {
1489 			uio->uio_resid = resid;
1490 			error = uiomove(mtod(m, caddr_t) + moff, len, uio);
1491 			resid = uio->uio_resid;
1492 			if (error)
1493 				goto release;
1494 		} else {
1495 			resid -= (size_t)len;
1496 		}
1497 
1498 		/*
1499 		 * Eat the entire mbuf or just a piece of it
1500 		 */
1501 		if (len == m->m_len - moff) {
1502 			if (m->m_flags & M_EOR)
1503 				flags |= MSG_EOR;
1504 			if (flags & MSG_PEEK) {
1505 				m = m->m_next;
1506 				moff = 0;
1507 			} else {
1508 				if (sio) {
1509 					n = sbunlinkmbuf(&so->so_rcv.sb, m,
1510 							 NULL);
1511 					sbappend(sio, m);
1512 					m = n;
1513 				} else {
1514 					m = sbunlinkmbuf(&so->so_rcv.sb, m,
1515 							 &free_chain);
1516 				}
1517 			}
1518 		} else {
1519 			if (flags & MSG_PEEK) {
1520 				moff += len;
1521 			} else {
1522 				if (sio) {
1523 					n = m_copym(m, 0, len, M_WAITOK);
1524 					if (n)
1525 						sbappend(sio, n);
1526 				}
1527 				m->m_data += len;
1528 				m->m_len -= len;
1529 				so->so_rcv.ssb_cc -= len;
1530 			}
1531 		}
1532 		if (so->so_oobmark) {
1533 			if ((flags & MSG_PEEK) == 0) {
1534 				so->so_oobmark -= len;
1535 				if (so->so_oobmark == 0) {
1536 					sosetstate(so, SS_RCVATMARK);
1537 					break;
1538 				}
1539 			} else {
1540 				offset += len;
1541 				if (offset == so->so_oobmark)
1542 					break;
1543 			}
1544 		}
1545 		if (flags & MSG_EOR)
1546 			break;
1547 		/*
1548 		 * If the MSG_WAITALL flag is set (for non-atomic socket),
1549 		 * we must not quit until resid == 0 or an error
1550 		 * termination.  If a signal/timeout occurs, return
1551 		 * with a short count but without error.
1552 		 * Keep signalsockbuf locked against other readers.
1553 		 */
1554 		while ((flags & MSG_WAITALL) && m == NULL &&
1555 		       resid > 0 && !sosendallatonce(so) &&
1556 		       so->so_rcv.ssb_mb == NULL)
1557 		{
1558 			if (so->so_error || so->so_rerror ||
1559 			    so->so_state & SS_CANTRCVMORE)
1560 				break;
1561 			/*
1562 			 * The window might have closed to zero, make
1563 			 * sure we send an ack now that we've drained
1564 			 * the buffer or we might end up blocking until
1565 			 * the idle takes over (5 seconds).
1566 			 */
1567 			if (pr->pr_flags & PR_WANTRCVD && so->so_pcb)
1568 				so_pru_rcvd(so, flags);
1569 			error = ssb_wait(&so->so_rcv);
1570 			if (error) {
1571 				ssb_unlock(&so->so_rcv);
1572 				error = 0;
1573 				goto done;
1574 			}
1575 			m = so->so_rcv.ssb_mb;
1576 		}
1577 	}
1578 
1579 	/*
1580 	 * If an atomic read was requested but unread data still remains
1581 	 * in the record, set MSG_TRUNC.
1582 	 */
1583 	if (m && pr->pr_flags & PR_ATOMIC)
1584 		flags |= MSG_TRUNC;
1585 
1586 	/*
1587 	 * Cleanup.  If an atomic read was requested drop any unread data.
1588 	 */
1589 	if ((flags & MSG_PEEK) == 0) {
1590 		if (m && (pr->pr_flags & PR_ATOMIC))
1591 			sbdroprecord(&so->so_rcv.sb);
1592 		if ((pr->pr_flags & PR_WANTRCVD) && so->so_pcb)
1593 			so_pru_rcvd(so, flags);
1594 	}
1595 
1596 	if (orig_resid == resid && orig_resid &&
1597 	    (flags & MSG_EOR) == 0 && (so->so_state & SS_CANTRCVMORE) == 0) {
1598 		ssb_unlock(&so->so_rcv);
1599 		goto restart;
1600 	}
1601 
1602 	if (flagsp)
1603 		*flagsp |= flags;
1604 release:
1605 	ssb_unlock(&so->so_rcv);
1606 done:
1607 	lwkt_reltoken(&so->so_rcv.ssb_token);
1608 	if (free_chain) {
1609 		if (free_rights && (pr->pr_flags & PR_RIGHTS) &&
1610 		    pr->pr_domain->dom_dispose)
1611 			pr->pr_domain->dom_dispose(free_chain);
1612 		m_freem(free_chain);
1613 	}
1614 	return (error);
1615 }
1616 
1617 int
1618 sorecvtcp(struct socket *so, struct sockaddr **psa, struct uio *uio,
1619 	  struct sockbuf *sio, struct mbuf **controlp, int *flagsp)
1620 {
1621 	struct mbuf *m, *n;
1622 	struct mbuf *free_chain = NULL;
1623 	int flags, len, error, offset;
1624 	struct protosw *pr = so->so_proto;
1625 	int moff;
1626 	int didoob;
1627 	size_t resid, orig_resid, restmp;
1628 
1629 	if (uio)
1630 		resid = uio->uio_resid;
1631 	else
1632 		resid = (size_t)(sio->sb_climit - sio->sb_cc);
1633 	orig_resid = resid;
1634 
1635 	if (psa)
1636 		*psa = NULL;
1637 	if (controlp)
1638 		*controlp = NULL;
1639 	if (flagsp)
1640 		flags = *flagsp &~ MSG_EOR;
1641 	else
1642 		flags = 0;
1643 	if (flags & MSG_OOB) {
1644 		m = m_get(M_WAITOK, MT_DATA);
1645 		error = so_pru_rcvoob(so, m, flags & MSG_PEEK);
1646 		if (error)
1647 			goto bad;
1648 		if (sio) {
1649 			do {
1650 				sbappend(sio, m);
1651 				KKASSERT(resid >= (size_t)m->m_len);
1652 				resid -= (size_t)m->m_len;
1653 			} while (resid > 0 && m);
1654 		} else {
1655 			do {
1656 				uio->uio_resid = resid;
1657 				error = uiomove(mtod(m, caddr_t),
1658 						(int)szmin(resid, m->m_len),
1659 						uio);
1660 				resid = uio->uio_resid;
1661 				m = m_free(m);
1662 			} while (uio->uio_resid && error == 0 && m);
1663 		}
1664 bad:
1665 		if (m)
1666 			m_freem(m);
1667 		return (error);
1668 	}
1669 
1670 	/*
1671 	 * The token interlocks against the protocol thread while
1672 	 * ssb_lock is a blocking lock against other userland entities.
1673 	 *
1674 	 * Lock a limited number of mbufs (not all, so sbcompress() still
1675 	 * works well).  The token is used as an interlock for sbwait() so
1676 	 * release it afterwords.
1677 	 */
1678 restart:
1679 	error = ssb_lock(&so->so_rcv, SBLOCKWAIT(flags));
1680 	if (error)
1681 		goto done;
1682 
1683 	lwkt_gettoken(&so->so_rcv.ssb_token);
1684 	m = so->so_rcv.ssb_mb;
1685 
1686 	/*
1687 	 * If we have less data than requested, block awaiting more
1688 	 * (subject to any timeout) if:
1689 	 *   1. the current count is less than the low water mark, or
1690 	 *   2. MSG_WAITALL is set, and it is possible to do the entire
1691 	 *	receive operation at once if we block (resid <= hiwat).
1692 	 *   3. MSG_DONTWAIT is not set
1693 	 * If MSG_WAITALL is set but resid is larger than the receive buffer,
1694 	 * we have to do the receive in sections, and thus risk returning
1695 	 * a short count if a timeout or signal occurs after we start.
1696 	 */
1697 	if (m == NULL || (((flags & MSG_DONTWAIT) == 0 &&
1698 	    (size_t)so->so_rcv.ssb_cc < resid) &&
1699 	    (so->so_rcv.ssb_cc < so->so_rcv.ssb_lowat ||
1700 	   ((flags & MSG_WAITALL) && resid <= (size_t)so->so_rcv.ssb_hiwat)))) {
1701 		KASSERT(m != NULL || !so->so_rcv.ssb_cc, ("receive 1"));
1702 		if (so->so_error) {
1703 			if (m)
1704 				goto dontblock;
1705 			lwkt_reltoken(&so->so_rcv.ssb_token);
1706 			error = so->so_error;
1707 			if ((flags & MSG_PEEK) == 0)
1708 				so->so_error = 0;
1709 			goto release;
1710 		}
1711 		if (so->so_state & SS_CANTRCVMORE) {
1712 			if (m)
1713 				goto dontblock;
1714 			lwkt_reltoken(&so->so_rcv.ssb_token);
1715 			goto release;
1716 		}
1717 		if ((so->so_state & (SS_ISCONNECTED|SS_ISCONNECTING)) == 0 &&
1718 		    (pr->pr_flags & PR_CONNREQUIRED)) {
1719 			lwkt_reltoken(&so->so_rcv.ssb_token);
1720 			error = ENOTCONN;
1721 			goto release;
1722 		}
1723 		if (resid == 0) {
1724 			lwkt_reltoken(&so->so_rcv.ssb_token);
1725 			goto release;
1726 		}
1727 		if (flags & (MSG_FNONBLOCKING|MSG_DONTWAIT)) {
1728 			lwkt_reltoken(&so->so_rcv.ssb_token);
1729 			error = EWOULDBLOCK;
1730 			goto release;
1731 		}
1732 		ssb_unlock(&so->so_rcv);
1733 		error = ssb_wait(&so->so_rcv);
1734 		lwkt_reltoken(&so->so_rcv.ssb_token);
1735 		if (error)
1736 			goto done;
1737 		goto restart;
1738 	}
1739 
1740 	/*
1741 	 * Token still held
1742 	 */
1743 dontblock:
1744 	n = m;
1745 	restmp = 0;
1746 	while (n && restmp < resid) {
1747 		n->m_flags |= M_SOLOCKED;
1748 		restmp += n->m_len;
1749 		if (n->m_next == NULL)
1750 			n = n->m_nextpkt;
1751 		else
1752 			n = n->m_next;
1753 	}
1754 
1755 	/*
1756 	 * Release token for loop
1757 	 */
1758 	lwkt_reltoken(&so->so_rcv.ssb_token);
1759 	if (uio && uio->uio_td && uio->uio_td->td_proc)
1760 		uio->uio_td->td_lwp->lwp_ru.ru_msgrcv++;
1761 
1762 	/*
1763 	 * note: m should be == sb_mb here.  Cache the next record while
1764 	 * cleaning up.  Note that calling m_free*() will break out critical
1765 	 * section.
1766 	 */
1767 	KKASSERT(m == so->so_rcv.ssb_mb);
1768 
1769 	/*
1770 	 * Copy to the UIO or mbuf return chain (*mp).
1771 	 *
1772 	 * NOTE: Token is not held for loop
1773 	 */
1774 	moff = 0;
1775 	offset = 0;
1776 	didoob = 0;
1777 
1778 	while (m && (m->m_flags & M_SOLOCKED) && resid > 0 && error == 0) {
1779 		KASSERT(m->m_type == MT_DATA || m->m_type == MT_HEADER,
1780 		    ("receive 3"));
1781 
1782 		soclrstate(so, SS_RCVATMARK);
1783 		len = (resid > INT_MAX) ? INT_MAX : resid;
1784 		if (so->so_oobmark && len > so->so_oobmark - offset)
1785 			len = so->so_oobmark - offset;
1786 		if (len > m->m_len - moff)
1787 			len = m->m_len - moff;
1788 
1789 		/*
1790 		 * Copy out to the UIO or pass the mbufs back to the SIO.
1791 		 * The SIO is dealt with when we eat the mbuf, but deal
1792 		 * with the resid here either way.
1793 		 */
1794 		if (uio) {
1795 			uio->uio_resid = resid;
1796 			error = uiomove(mtod(m, caddr_t) + moff, len, uio);
1797 			resid = uio->uio_resid;
1798 			if (error)
1799 				goto release;
1800 		} else {
1801 			resid -= (size_t)len;
1802 		}
1803 
1804 		/*
1805 		 * Eat the entire mbuf or just a piece of it
1806 		 */
1807 		offset += len;
1808 		if (len == m->m_len - moff) {
1809 			m = m->m_next;
1810 			moff = 0;
1811 		} else {
1812 			moff += len;
1813 		}
1814 
1815 		/*
1816 		 * Check oobmark
1817 		 */
1818 		if (so->so_oobmark && offset == so->so_oobmark) {
1819 			didoob = 1;
1820 			break;
1821 		}
1822 	}
1823 
1824 	/*
1825 	 * Synchronize sockbuf with data we read.
1826 	 *
1827 	 * NOTE: (m) is junk on entry (it could be left over from the
1828 	 *	 previous loop).
1829 	 */
1830 	if ((flags & MSG_PEEK) == 0) {
1831 		lwkt_gettoken(&so->so_rcv.ssb_token);
1832 		m = so->so_rcv.ssb_mb;
1833 		while (m && offset >= m->m_len) {
1834 			if (so->so_oobmark) {
1835 				so->so_oobmark -= m->m_len;
1836 				if (so->so_oobmark == 0) {
1837 					sosetstate(so, SS_RCVATMARK);
1838 					didoob = 1;
1839 				}
1840 			}
1841 			offset -= m->m_len;
1842 			if (sio) {
1843 				n = sbunlinkmbuf(&so->so_rcv.sb, m, NULL);
1844 				sbappend(sio, m);
1845 				m = n;
1846 			} else {
1847 				m = sbunlinkmbuf(&so->so_rcv.sb,
1848 						 m, &free_chain);
1849 			}
1850 		}
1851 		if (offset) {
1852 			KKASSERT(m);
1853 			if (sio) {
1854 				n = m_copym(m, 0, offset, M_WAITOK);
1855 				if (n)
1856 					sbappend(sio, n);
1857 			}
1858 			m->m_data += offset;
1859 			m->m_len -= offset;
1860 			so->so_rcv.ssb_cc -= offset;
1861 			if (so->so_oobmark) {
1862 				so->so_oobmark -= offset;
1863 				if (so->so_oobmark == 0) {
1864 					sosetstate(so, SS_RCVATMARK);
1865 					didoob = 1;
1866 				}
1867 			}
1868 			offset = 0;
1869 		}
1870 		lwkt_reltoken(&so->so_rcv.ssb_token);
1871 	}
1872 
1873 	/*
1874 	 * If the MSG_WAITALL flag is set (for non-atomic socket),
1875 	 * we must not quit until resid == 0 or an error termination.
1876 	 *
1877 	 * If a signal/timeout occurs, return with a short count but without
1878 	 * error.
1879 	 *
1880 	 * Keep signalsockbuf locked against other readers.
1881 	 *
1882 	 * XXX if MSG_PEEK we currently do quit.
1883 	 */
1884 	if ((flags & MSG_WAITALL) && !(flags & MSG_PEEK) &&
1885 	    didoob == 0 && resid > 0 &&
1886 	    !sosendallatonce(so)) {
1887 		lwkt_gettoken(&so->so_rcv.ssb_token);
1888 		error = 0;
1889 		while ((m = so->so_rcv.ssb_mb) == NULL) {
1890 			if (so->so_error || (so->so_state & SS_CANTRCVMORE)) {
1891 				error = so->so_error;
1892 				break;
1893 			}
1894 			/*
1895 			 * The window might have closed to zero, make
1896 			 * sure we send an ack now that we've drained
1897 			 * the buffer or we might end up blocking until
1898 			 * the idle takes over (5 seconds).
1899 			 */
1900 			if (so->so_pcb)
1901 				so_pru_rcvd_async(so);
1902 			if (so->so_rcv.ssb_mb == NULL)
1903 				error = ssb_wait(&so->so_rcv);
1904 			if (error) {
1905 				lwkt_reltoken(&so->so_rcv.ssb_token);
1906 				ssb_unlock(&so->so_rcv);
1907 				error = 0;
1908 				goto done;
1909 			}
1910 		}
1911 		if (m && error == 0)
1912 			goto dontblock;
1913 		lwkt_reltoken(&so->so_rcv.ssb_token);
1914 	}
1915 
1916 	/*
1917 	 * Token not held here.
1918 	 *
1919 	 * Cleanup.  If an atomic read was requested drop any unread data XXX
1920 	 */
1921 	if ((flags & MSG_PEEK) == 0) {
1922 		if (so->so_pcb)
1923 			so_pru_rcvd_async(so);
1924 	}
1925 
1926 	if (orig_resid == resid && orig_resid &&
1927 	    (so->so_state & SS_CANTRCVMORE) == 0) {
1928 		ssb_unlock(&so->so_rcv);
1929 		goto restart;
1930 	}
1931 
1932 	if (flagsp)
1933 		*flagsp |= flags;
1934 release:
1935 	ssb_unlock(&so->so_rcv);
1936 done:
1937 	if (free_chain)
1938 		m_freem(free_chain);
1939 	return (error);
1940 }
1941 
1942 /*
1943  * Shut a socket down.  Note that we do not get a frontend lock as we
1944  * want to be able to shut the socket down even if another thread is
1945  * blocked in a read(), thus waking it up.
1946  */
1947 int
1948 soshutdown(struct socket *so, int how)
1949 {
1950 	if (!(how == SHUT_RD || how == SHUT_WR || how == SHUT_RDWR))
1951 		return (EINVAL);
1952 
1953 	if (how != SHUT_WR) {
1954 		/*ssb_lock(&so->so_rcv, M_WAITOK);*/
1955 		sorflush(so);
1956 		/*ssb_unlock(&so->so_rcv);*/
1957 	}
1958 	if (how != SHUT_RD)
1959 		return (so_pru_shutdown(so));
1960 	return (0);
1961 }
1962 
1963 void
1964 sorflush(struct socket *so)
1965 {
1966 	struct signalsockbuf *ssb = &so->so_rcv;
1967 	struct protosw *pr = so->so_proto;
1968 	struct signalsockbuf asb;
1969 
1970 	atomic_set_int(&ssb->ssb_flags, SSB_NOINTR);
1971 
1972 	lwkt_gettoken(&ssb->ssb_token);
1973 	socantrcvmore(so);
1974 	asb = *ssb;
1975 
1976 	/*
1977 	 * Can't just blow up the ssb structure here
1978 	 */
1979 	bzero(&ssb->sb, sizeof(ssb->sb));
1980 	ssb->ssb_timeo = 0;
1981 	ssb->ssb_lowat = 0;
1982 	ssb->ssb_hiwat = 0;
1983 	ssb->ssb_mbmax = 0;
1984 	atomic_clear_int(&ssb->ssb_flags, SSB_CLEAR_MASK);
1985 
1986 	if ((pr->pr_flags & PR_RIGHTS) && pr->pr_domain->dom_dispose)
1987 		(*pr->pr_domain->dom_dispose)(asb.ssb_mb);
1988 	ssb_release(&asb, so);
1989 
1990 	lwkt_reltoken(&ssb->ssb_token);
1991 }
1992 
1993 #ifdef INET
1994 static int
1995 do_setopt_accept_filter(struct socket *so, struct sockopt *sopt)
1996 {
1997 	struct accept_filter_arg	*afap = NULL;
1998 	struct accept_filter	*afp;
1999 	struct so_accf	*af = so->so_accf;
2000 	int	error = 0;
2001 
2002 	/* do not set/remove accept filters on non listen sockets */
2003 	if ((so->so_options & SO_ACCEPTCONN) == 0) {
2004 		error = EINVAL;
2005 		goto out;
2006 	}
2007 
2008 	/* removing the filter */
2009 	if (sopt == NULL) {
2010 		if (af != NULL) {
2011 			if (af->so_accept_filter != NULL &&
2012 				af->so_accept_filter->accf_destroy != NULL) {
2013 				af->so_accept_filter->accf_destroy(so);
2014 			}
2015 			if (af->so_accept_filter_str != NULL) {
2016 				kfree(af->so_accept_filter_str, M_ACCF);
2017 			}
2018 			kfree(af, M_ACCF);
2019 			so->so_accf = NULL;
2020 		}
2021 		so->so_options &= ~SO_ACCEPTFILTER;
2022 		return (0);
2023 	}
2024 	/* adding a filter */
2025 	/* must remove previous filter first */
2026 	if (af != NULL) {
2027 		error = EINVAL;
2028 		goto out;
2029 	}
2030 	/* don't put large objects on the kernel stack */
2031 	afap = kmalloc(sizeof(*afap), M_TEMP, M_WAITOK);
2032 	error = sooptcopyin(sopt, afap, sizeof *afap, sizeof *afap);
2033 	afap->af_name[sizeof(afap->af_name)-1] = '\0';
2034 	afap->af_arg[sizeof(afap->af_arg)-1] = '\0';
2035 	if (error)
2036 		goto out;
2037 	afp = accept_filt_get(afap->af_name);
2038 	if (afp == NULL) {
2039 		error = ENOENT;
2040 		goto out;
2041 	}
2042 	af = kmalloc(sizeof(*af), M_ACCF, M_WAITOK | M_ZERO);
2043 	if (afp->accf_create != NULL) {
2044 		if (afap->af_name[0] != '\0') {
2045 			int len = strlen(afap->af_name) + 1;
2046 
2047 			af->so_accept_filter_str = kmalloc(len, M_ACCF,
2048 							   M_WAITOK);
2049 			strcpy(af->so_accept_filter_str, afap->af_name);
2050 		}
2051 		af->so_accept_filter_arg = afp->accf_create(so, afap->af_arg);
2052 		if (af->so_accept_filter_arg == NULL) {
2053 			kfree(af->so_accept_filter_str, M_ACCF);
2054 			kfree(af, M_ACCF);
2055 			so->so_accf = NULL;
2056 			error = EINVAL;
2057 			goto out;
2058 		}
2059 	}
2060 	af->so_accept_filter = afp;
2061 	so->so_accf = af;
2062 	so->so_options |= SO_ACCEPTFILTER;
2063 out:
2064 	if (afap != NULL)
2065 		kfree(afap, M_TEMP);
2066 	return (error);
2067 }
2068 #endif /* INET */
2069 
2070 /*
2071  * Perhaps this routine, and sooptcopyout(), below, ought to come in
2072  * an additional variant to handle the case where the option value needs
2073  * to be some kind of integer, but not a specific size.
2074  * In addition to their use here, these functions are also called by the
2075  * protocol-level pr_ctloutput() routines.
2076  */
2077 int
2078 sooptcopyin(struct sockopt *sopt, void *buf, size_t len, size_t minlen)
2079 {
2080 	return soopt_to_kbuf(sopt, buf, len, minlen);
2081 }
2082 
2083 int
2084 soopt_to_kbuf(struct sockopt *sopt, void *buf, size_t len, size_t minlen)
2085 {
2086 	size_t	valsize;
2087 
2088 	KKASSERT(!sopt->sopt_val || kva_p(sopt->sopt_val));
2089 	KKASSERT(kva_p(buf));
2090 
2091 	/*
2092 	 * If the user gives us more than we wanted, we ignore it,
2093 	 * but if we don't get the minimum length the caller
2094 	 * wants, we return EINVAL.  On success, sopt->sopt_valsize
2095 	 * is set to however much we actually retrieved.
2096 	 */
2097 	if ((valsize = sopt->sopt_valsize) < minlen)
2098 		return EINVAL;
2099 	if (valsize > len)
2100 		sopt->sopt_valsize = valsize = len;
2101 
2102 	bcopy(sopt->sopt_val, buf, valsize);
2103 	return 0;
2104 }
2105 
2106 
2107 int
2108 sosetopt(struct socket *so, struct sockopt *sopt)
2109 {
2110 	int	error, optval;
2111 	struct	linger l;
2112 	struct	timeval tv;
2113 	u_long  val;
2114 	uint32_t val32;
2115 	struct signalsockbuf *sotmp;
2116 
2117 	error = 0;
2118 	sopt->sopt_dir = SOPT_SET;
2119 	if (sopt->sopt_level != SOL_SOCKET) {
2120 		if (so->so_proto && so->so_proto->pr_ctloutput) {
2121 			return (so_pr_ctloutput(so, sopt));
2122 		}
2123 		error = ENOPROTOOPT;
2124 	} else {
2125 		switch (sopt->sopt_name) {
2126 #ifdef INET
2127 		case SO_ACCEPTFILTER:
2128 			error = do_setopt_accept_filter(so, sopt);
2129 			if (error)
2130 				goto bad;
2131 			break;
2132 #endif /* INET */
2133 		case SO_LINGER:
2134 			error = sooptcopyin(sopt, &l, sizeof l, sizeof l);
2135 			if (error)
2136 				goto bad;
2137 
2138 			so->so_linger = l.l_linger;
2139 			if (l.l_onoff)
2140 				so->so_options |= SO_LINGER;
2141 			else
2142 				so->so_options &= ~SO_LINGER;
2143 			break;
2144 
2145 		case SO_DEBUG:
2146 		case SO_KEEPALIVE:
2147 		case SO_DONTROUTE:
2148 		case SO_USELOOPBACK:
2149 		case SO_BROADCAST:
2150 		case SO_REUSEADDR:
2151 		case SO_REUSEPORT:
2152 		case SO_OOBINLINE:
2153 		case SO_TIMESTAMP:
2154 		case SO_NOSIGPIPE:
2155 		case SO_RERROR:
2156 		case SO_PASSCRED:
2157 			error = sooptcopyin(sopt, &optval, sizeof optval,
2158 					    sizeof optval);
2159 			if (error)
2160 				goto bad;
2161 			if (optval)
2162 				so->so_options |= sopt->sopt_name;
2163 			else
2164 				so->so_options &= ~sopt->sopt_name;
2165 			break;
2166 
2167 		case SO_SNDBUF:
2168 		case SO_RCVBUF:
2169 		case SO_SNDLOWAT:
2170 		case SO_RCVLOWAT:
2171 			error = sooptcopyin(sopt, &optval, sizeof optval,
2172 					    sizeof optval);
2173 			if (error)
2174 				goto bad;
2175 
2176 			/*
2177 			 * Values < 1 make no sense for any of these
2178 			 * options, so disallow them.
2179 			 */
2180 			if (optval < 1) {
2181 				error = EINVAL;
2182 				goto bad;
2183 			}
2184 
2185 			switch (sopt->sopt_name) {
2186 			case SO_SNDBUF:
2187 			case SO_RCVBUF:
2188 				if (ssb_reserve(sopt->sopt_name == SO_SNDBUF ?
2189 				    &so->so_snd : &so->so_rcv, (u_long)optval,
2190 				    so,
2191 				    &curproc->p_rlimit[RLIMIT_SBSIZE]) == 0) {
2192 					error = ENOBUFS;
2193 					goto bad;
2194 				}
2195 				sotmp = (sopt->sopt_name == SO_SNDBUF) ?
2196 						&so->so_snd : &so->so_rcv;
2197 				atomic_clear_int(&sotmp->ssb_flags,
2198 						 SSB_AUTOSIZE);
2199 				break;
2200 
2201 			/*
2202 			 * Make sure the low-water is never greater than
2203 			 * the high-water.
2204 			 */
2205 			case SO_SNDLOWAT:
2206 				so->so_snd.ssb_lowat =
2207 				    (optval > so->so_snd.ssb_hiwat) ?
2208 				    so->so_snd.ssb_hiwat : optval;
2209 				atomic_clear_int(&so->so_snd.ssb_flags,
2210 						 SSB_AUTOLOWAT);
2211 				break;
2212 			case SO_RCVLOWAT:
2213 				so->so_rcv.ssb_lowat =
2214 				    (optval > so->so_rcv.ssb_hiwat) ?
2215 				    so->so_rcv.ssb_hiwat : optval;
2216 				atomic_clear_int(&so->so_rcv.ssb_flags,
2217 						 SSB_AUTOLOWAT);
2218 				break;
2219 			}
2220 			break;
2221 
2222 		case SO_SNDTIMEO:
2223 		case SO_RCVTIMEO:
2224 			error = sooptcopyin(sopt, &tv, sizeof tv,
2225 					    sizeof tv);
2226 			if (error)
2227 				goto bad;
2228 
2229 			/* assert(hz > 0); */
2230 			if (tv.tv_sec < 0 || tv.tv_sec > INT_MAX / hz ||
2231 			    tv.tv_usec < 0 || tv.tv_usec >= 1000000) {
2232 				error = EDOM;
2233 				goto bad;
2234 			}
2235 			/* assert(tick > 0); */
2236 			/* assert(ULONG_MAX - INT_MAX >= 1000000); */
2237 			val = (u_long)(tv.tv_sec * hz) + tv.tv_usec / ustick;
2238 			if (val > INT_MAX) {
2239 				error = EDOM;
2240 				goto bad;
2241 			}
2242 			if (val == 0 && tv.tv_usec != 0)
2243 				val = 1;
2244 
2245 			switch (sopt->sopt_name) {
2246 			case SO_SNDTIMEO:
2247 				so->so_snd.ssb_timeo = val;
2248 				break;
2249 			case SO_RCVTIMEO:
2250 				so->so_rcv.ssb_timeo = val;
2251 				break;
2252 			}
2253 			break;
2254 
2255 		case SO_USER_COOKIE:
2256 			error = sooptcopyin(sopt, &val32, sizeof val32,
2257 					    sizeof val32);
2258 			if (error)
2259 				goto bad;
2260 			so->so_user_cookie = val32;
2261 			break;
2262 
2263 		default:
2264 			error = ENOPROTOOPT;
2265 			break;
2266 		}
2267 		if (error == 0 && so->so_proto && so->so_proto->pr_ctloutput) {
2268 			(void) so_pr_ctloutput(so, sopt);
2269 		}
2270 	}
2271 bad:
2272 	return (error);
2273 }
2274 
2275 /* Helper routine for getsockopt */
2276 int
2277 sooptcopyout(struct sockopt *sopt, const void *buf, size_t len)
2278 {
2279 	soopt_from_kbuf(sopt, buf, len);
2280 	return 0;
2281 }
2282 
2283 void
2284 soopt_from_kbuf(struct sockopt *sopt, const void *buf, size_t len)
2285 {
2286 	size_t	valsize;
2287 
2288 	if (len == 0) {
2289 		sopt->sopt_valsize = 0;
2290 		return;
2291 	}
2292 
2293 	KKASSERT(!sopt->sopt_val || kva_p(sopt->sopt_val));
2294 	KKASSERT(kva_p(buf));
2295 
2296 	/*
2297 	 * Documented get behavior is that we always return a value,
2298 	 * possibly truncated to fit in the user's buffer.
2299 	 * Traditional behavior is that we always tell the user
2300 	 * precisely how much we copied, rather than something useful
2301 	 * like the total amount we had available for her.
2302 	 * Note that this interface is not idempotent; the entire answer must
2303 	 * generated ahead of time.
2304 	 */
2305 	valsize = szmin(len, sopt->sopt_valsize);
2306 	sopt->sopt_valsize = valsize;
2307 	if (sopt->sopt_val != 0) {
2308 		bcopy(buf, sopt->sopt_val, valsize);
2309 	}
2310 }
2311 
2312 int
2313 sogetopt(struct socket *so, struct sockopt *sopt)
2314 {
2315 	int	error, optval;
2316 	long	optval_l;
2317 	struct	linger l;
2318 	struct	timeval tv;
2319 	uint32_t val32;
2320 #ifdef INET
2321 	struct accept_filter_arg *afap;
2322 #endif
2323 
2324 	error = 0;
2325 	sopt->sopt_dir = SOPT_GET;
2326 	if (sopt->sopt_level != SOL_SOCKET) {
2327 		if (so->so_proto && so->so_proto->pr_ctloutput) {
2328 			return (so_pr_ctloutput(so, sopt));
2329 		} else
2330 			return (ENOPROTOOPT);
2331 	} else {
2332 		switch (sopt->sopt_name) {
2333 #ifdef INET
2334 		case SO_ACCEPTFILTER:
2335 			if ((so->so_options & SO_ACCEPTCONN) == 0)
2336 				return (EINVAL);
2337 			afap = kmalloc(sizeof(*afap), M_TEMP,
2338 				       M_WAITOK | M_ZERO);
2339 			if ((so->so_options & SO_ACCEPTFILTER) != 0) {
2340 				strcpy(afap->af_name, so->so_accf->so_accept_filter->accf_name);
2341 				if (so->so_accf->so_accept_filter_str != NULL)
2342 					strcpy(afap->af_arg, so->so_accf->so_accept_filter_str);
2343 			}
2344 			error = sooptcopyout(sopt, afap, sizeof(*afap));
2345 			kfree(afap, M_TEMP);
2346 			break;
2347 #endif /* INET */
2348 
2349 		case SO_LINGER:
2350 			l.l_onoff = so->so_options & SO_LINGER;
2351 			l.l_linger = so->so_linger;
2352 			error = sooptcopyout(sopt, &l, sizeof l);
2353 			break;
2354 
2355 		case SO_USELOOPBACK:
2356 		case SO_DONTROUTE:
2357 		case SO_DEBUG:
2358 		case SO_KEEPALIVE:
2359 		case SO_REUSEADDR:
2360 		case SO_REUSEPORT:
2361 		case SO_BROADCAST:
2362 		case SO_OOBINLINE:
2363 		case SO_TIMESTAMP:
2364 		case SO_NOSIGPIPE:
2365 		case SO_RERROR:
2366 		case SO_PASSCRED:
2367 			optval = so->so_options & sopt->sopt_name;
2368 integer:
2369 			error = sooptcopyout(sopt, &optval, sizeof optval);
2370 			break;
2371 
2372 		case SO_TYPE:
2373 			optval = so->so_type;
2374 			goto integer;
2375 
2376 		case SO_ERROR:
2377 			if (so->so_error) {
2378 				optval = so->so_error;
2379 				so->so_error = 0;
2380 			} else {
2381 				optval = so->so_rerror;
2382 				so->so_rerror = 0;
2383 			}
2384 			goto integer;
2385 
2386 		case SO_SNDBUF:
2387 			optval = so->so_snd.ssb_hiwat;
2388 			goto integer;
2389 
2390 		case SO_RCVBUF:
2391 			optval = so->so_rcv.ssb_hiwat;
2392 			goto integer;
2393 
2394 		case SO_SNDLOWAT:
2395 			optval = so->so_snd.ssb_lowat;
2396 			goto integer;
2397 
2398 		case SO_RCVLOWAT:
2399 			optval = so->so_rcv.ssb_lowat;
2400 			goto integer;
2401 
2402 		case SO_SNDTIMEO:
2403 		case SO_RCVTIMEO:
2404 			optval = (sopt->sopt_name == SO_SNDTIMEO ?
2405 				  so->so_snd.ssb_timeo : so->so_rcv.ssb_timeo);
2406 
2407 			tv.tv_sec = optval / hz;
2408 			tv.tv_usec = (optval % hz) * ustick;
2409 			error = sooptcopyout(sopt, &tv, sizeof tv);
2410 			break;
2411 
2412 		case SO_SNDSPACE:
2413 			optval_l = ssb_space(&so->so_snd);
2414 			error = sooptcopyout(sopt, &optval_l, sizeof(optval_l));
2415 			break;
2416 
2417 		case SO_CPUHINT:
2418 			optval = -1; /* no hint */
2419 			goto integer;
2420 
2421 		case SO_USER_COOKIE:
2422 			val32 = so->so_user_cookie;
2423 			error = sooptcopyout(sopt, &val32, sizeof(val32));
2424 			break;
2425 
2426 		default:
2427 			error = ENOPROTOOPT;
2428 			break;
2429 		}
2430 		if (error == 0 && so->so_proto && so->so_proto->pr_ctloutput)
2431 			so_pr_ctloutput(so, sopt);
2432 		return (error);
2433 	}
2434 }
2435 
2436 /* XXX; prepare mbuf for (__FreeBSD__ < 3) routines. */
2437 int
2438 soopt_getm(struct sockopt *sopt, struct mbuf **mp)
2439 {
2440 	struct mbuf *m, *m_prev;
2441 	int sopt_size = sopt->sopt_valsize, msize;
2442 
2443 	m = m_getl(sopt_size, sopt->sopt_td ? M_WAITOK : M_NOWAIT, MT_DATA,
2444 		   0, &msize);
2445 	if (m == NULL)
2446 		return (ENOBUFS);
2447 	m->m_len = min(msize, sopt_size);
2448 	sopt_size -= m->m_len;
2449 	*mp = m;
2450 	m_prev = m;
2451 
2452 	while (sopt_size > 0) {
2453 		m = m_getl(sopt_size, sopt->sopt_td ? M_WAITOK : M_NOWAIT,
2454 			   MT_DATA, 0, &msize);
2455 		if (m == NULL) {
2456 			m_freem(*mp);
2457 			return (ENOBUFS);
2458 		}
2459 		m->m_len = min(msize, sopt_size);
2460 		sopt_size -= m->m_len;
2461 		m_prev->m_next = m;
2462 		m_prev = m;
2463 	}
2464 	return (0);
2465 }
2466 
2467 /* XXX; copyin sopt data into mbuf chain for (__FreeBSD__ < 3) routines. */
2468 int
2469 soopt_mcopyin(struct sockopt *sopt, struct mbuf *m)
2470 {
2471 	soopt_to_mbuf(sopt, m);
2472 	return 0;
2473 }
2474 
2475 void
2476 soopt_to_mbuf(struct sockopt *sopt, struct mbuf *m)
2477 {
2478 	size_t valsize;
2479 	void *val;
2480 
2481 	KKASSERT(!sopt->sopt_val || kva_p(sopt->sopt_val));
2482 	KKASSERT(kva_p(m));
2483 	if (sopt->sopt_val == NULL)
2484 		return;
2485 	val = sopt->sopt_val;
2486 	valsize = sopt->sopt_valsize;
2487 	while (m != NULL && valsize >= m->m_len) {
2488 		bcopy(val, mtod(m, char *), m->m_len);
2489 		valsize -= m->m_len;
2490 		val = (caddr_t)val + m->m_len;
2491 		m = m->m_next;
2492 	}
2493 	if (m != NULL) /* should be allocated enoughly at ip6_sooptmcopyin() */
2494 		panic("ip6_sooptmcopyin");
2495 }
2496 
2497 /* XXX; copyout mbuf chain data into soopt for (__FreeBSD__ < 3) routines. */
2498 int
2499 soopt_mcopyout(struct sockopt *sopt, struct mbuf *m)
2500 {
2501 	return soopt_from_mbuf(sopt, m);
2502 }
2503 
2504 int
2505 soopt_from_mbuf(struct sockopt *sopt, struct mbuf *m)
2506 {
2507 	struct mbuf *m0 = m;
2508 	size_t valsize = 0;
2509 	size_t maxsize;
2510 	void *val;
2511 
2512 	KKASSERT(!sopt->sopt_val || kva_p(sopt->sopt_val));
2513 	KKASSERT(kva_p(m));
2514 	if (sopt->sopt_val == NULL)
2515 		return 0;
2516 	val = sopt->sopt_val;
2517 	maxsize = sopt->sopt_valsize;
2518 	while (m != NULL && maxsize >= m->m_len) {
2519 		bcopy(mtod(m, char *), val, m->m_len);
2520 	       maxsize -= m->m_len;
2521 	       val = (caddr_t)val + m->m_len;
2522 	       valsize += m->m_len;
2523 	       m = m->m_next;
2524 	}
2525 	if (m != NULL) {
2526 		/* enough soopt buffer should be given from user-land */
2527 		m_freem(m0);
2528 		return (EINVAL);
2529 	}
2530 	sopt->sopt_valsize = valsize;
2531 	return 0;
2532 }
2533 
2534 void
2535 sohasoutofband(struct socket *so)
2536 {
2537 	if (so->so_sigio != NULL)
2538 		pgsigio(so->so_sigio, SIGURG, 0);
2539 	/*
2540 	 * NOTE:
2541 	 * There is no need to use NOTE_OOB as KNOTE hint here:
2542 	 * soread filter depends on so_oobmark and SS_RCVATMARK
2543 	 * so_state.  NOTE_OOB would cause unnecessary penalty
2544 	 * in KNOTE, if there was knote processing contention.
2545 	 */
2546 	KNOTE(&so->so_rcv.ssb_kq.ki_note, 0);
2547 }
2548 
2549 int
2550 sokqfilter(struct file *fp, struct knote *kn)
2551 {
2552 	struct socket *so = (struct socket *)kn->kn_fp->f_data;
2553 	struct signalsockbuf *ssb;
2554 
2555 	switch (kn->kn_filter) {
2556 	case EVFILT_READ:
2557 		if (so->so_options & SO_ACCEPTCONN)
2558 			kn->kn_fop = &solisten_filtops;
2559 		else
2560 			kn->kn_fop = &soread_filtops;
2561 		ssb = &so->so_rcv;
2562 		break;
2563 	case EVFILT_WRITE:
2564 		kn->kn_fop = &sowrite_filtops;
2565 		ssb = &so->so_snd;
2566 		break;
2567 	case EVFILT_EXCEPT:
2568 		kn->kn_fop = &soexcept_filtops;
2569 		ssb = &so->so_rcv;
2570 		break;
2571 	default:
2572 		return (EOPNOTSUPP);
2573 	}
2574 
2575 	knote_insert(&ssb->ssb_kq.ki_note, kn);
2576 	atomic_set_int(&ssb->ssb_flags, SSB_KNOTE);
2577 	return (0);
2578 }
2579 
2580 static void
2581 filt_sordetach(struct knote *kn)
2582 {
2583 	struct socket *so = (struct socket *)kn->kn_fp->f_data;
2584 
2585 	knote_remove(&so->so_rcv.ssb_kq.ki_note, kn);
2586 	if (SLIST_EMPTY(&so->so_rcv.ssb_kq.ki_note))
2587 		atomic_clear_int(&so->so_rcv.ssb_flags, SSB_KNOTE);
2588 }
2589 
2590 /*ARGSUSED*/
2591 static int
2592 filt_soread(struct knote *kn, long hint __unused)
2593 {
2594 	struct socket *so = (struct socket *)kn->kn_fp->f_data;
2595 
2596 	if (kn->kn_sfflags & NOTE_OOB) {
2597 		if ((so->so_oobmark || (so->so_state & SS_RCVATMARK))) {
2598 			kn->kn_fflags |= NOTE_OOB;
2599 			return (1);
2600 		}
2601 		return (0);
2602 	}
2603 	kn->kn_data = so->so_rcv.ssb_cc;
2604 
2605 	if (so->so_state & SS_CANTRCVMORE) {
2606 		/*
2607 		 * Only set NODATA if all data has been exhausted.
2608 		 *
2609 		 * If HUPONLY is flagged, linux only issues the HUP on
2610 		 * a fully closed socket, not a half-closed socket.
2611 		 *
2612 		 * LOWAT is not applicable with a pending EOF.
2613 		 *
2614 		 * WARNING: If we issue a spurious event to poll() it will
2615 		 *	    de-register the event.
2616 		 */
2617 		if (kn->kn_data == 0)
2618 			kn->kn_flags |= EV_NODATA;
2619 		kn->kn_flags |= EV_EOF;
2620 		kn->kn_fflags = so->so_error;
2621 		if (so->so_state & SS_CANTSENDMORE) {
2622 			kn->kn_flags |= EV_HUP;
2623 			return (1);
2624 		}
2625 		if ((kn->kn_sfflags & NOTE_HUPONLY) == 0)
2626 			return (1);
2627 		return 0;
2628 	}
2629 	if (so->so_error || so->so_rerror)
2630 		return (1);
2631 
2632 	/*
2633 	 * Normal operation if HUPONLY is not set.  If HUPONLY is set
2634 	 * we only return positive on EOF/HUP above.
2635 	 *
2636 	 * WARNING: If we issue a spurious event to poll() it will de-register
2637 	 *	    the event.
2638 	 */
2639 	if ((kn->kn_sfflags & NOTE_HUPONLY) == 0) {
2640 		if (kn->kn_sfflags & NOTE_LOWAT)
2641 			return (kn->kn_data >= kn->kn_sdata);
2642 		return ((kn->kn_data >= so->so_rcv.ssb_lowat) ||
2643 			!TAILQ_EMPTY(&so->so_comp));
2644 	}
2645 	return 0;
2646 }
2647 
2648 static void
2649 filt_sowdetach(struct knote *kn)
2650 {
2651 	struct socket *so = (struct socket *)kn->kn_fp->f_data;
2652 
2653 	knote_remove(&so->so_snd.ssb_kq.ki_note, kn);
2654 	if (SLIST_EMPTY(&so->so_snd.ssb_kq.ki_note))
2655 		atomic_clear_int(&so->so_snd.ssb_flags, SSB_KNOTE);
2656 }
2657 
2658 /*ARGSUSED*/
2659 static int
2660 filt_sowrite(struct knote *kn, long hint __unused)
2661 {
2662 	struct socket *so = (struct socket *)kn->kn_fp->f_data;
2663 
2664 	if (so->so_snd.ssb_flags & SSB_PREALLOC)
2665 		kn->kn_data = ssb_space_prealloc(&so->so_snd);
2666 	else
2667 		kn->kn_data = ssb_space(&so->so_snd);
2668 
2669 	if (so->so_state & SS_CANTSENDMORE) {
2670 		kn->kn_flags |= (EV_EOF | EV_NODATA);
2671 		if (so->so_state & SS_CANTRCVMORE)
2672 			kn->kn_flags |= EV_HUP;
2673 		kn->kn_fflags = so->so_error;
2674 		return (1);
2675 	}
2676 	if (so->so_error)	/* temporary udp error */
2677 		return (1);
2678 	if (((so->so_state & SS_ISCONNECTED) == 0) &&
2679 	    (so->so_proto->pr_flags & PR_CONNREQUIRED))
2680 		return (0);
2681 	if (kn->kn_sfflags & NOTE_LOWAT)
2682 		return (kn->kn_data >= kn->kn_sdata);
2683 	return (kn->kn_data >= so->so_snd.ssb_lowat);
2684 }
2685 
2686 /*ARGSUSED*/
2687 static int
2688 filt_solisten(struct knote *kn, long hint __unused)
2689 {
2690 	struct socket *so = (struct socket *)kn->kn_fp->f_data;
2691 	int qlen = so->so_qlen;
2692 
2693 	if (soavailconn > 0 && qlen > soavailconn)
2694 		qlen = soavailconn;
2695 	kn->kn_data = qlen;
2696 
2697 	return (!TAILQ_EMPTY(&so->so_comp));
2698 }
2699