xref: /dflybsd-src/sys/kern/uipc_socket.c (revision 085476612a07754b8438b2c12f80a7ee1e2a4cc7)
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/thread2.h>
93 #include <sys/socketvar2.h>
94 #include <sys/spinlock2.h>
95 
96 #include <machine/limits.h>
97 
98 #ifdef INET
99 extern int tcp_sosend_agglim;
100 extern int tcp_sosend_async;
101 extern int tcp_sosend_jcluster;
102 extern int udp_sosend_async;
103 extern int udp_sosend_prepend;
104 
105 static int	 do_setopt_accept_filter(struct socket *so, struct sockopt *sopt);
106 #endif /* INET */
107 
108 static void 	filt_sordetach(struct knote *kn);
109 static int 	filt_soread(struct knote *kn, long hint);
110 static void 	filt_sowdetach(struct knote *kn);
111 static int	filt_sowrite(struct knote *kn, long hint);
112 static int	filt_solisten(struct knote *kn, long hint);
113 
114 static int	soclose_sync(struct socket *so, int fflag);
115 static void	soclose_fast(struct socket *so);
116 
117 static struct filterops solisten_filtops =
118 	{ FILTEROP_ISFD|FILTEROP_MPSAFE, NULL, filt_sordetach, filt_solisten };
119 static struct filterops soread_filtops =
120 	{ FILTEROP_ISFD|FILTEROP_MPSAFE, NULL, filt_sordetach, filt_soread };
121 static struct filterops sowrite_filtops =
122 	{ FILTEROP_ISFD|FILTEROP_MPSAFE, NULL, filt_sowdetach, filt_sowrite };
123 static struct filterops soexcept_filtops =
124 	{ FILTEROP_ISFD|FILTEROP_MPSAFE, NULL, filt_sordetach, filt_soread };
125 
126 MALLOC_DEFINE(M_SOCKET, "socket", "socket struct");
127 MALLOC_DEFINE(M_SONAME, "soname", "socket name");
128 MALLOC_DEFINE(M_PCB, "pcb", "protocol control block");
129 
130 
131 static int somaxconn = SOMAXCONN;
132 SYSCTL_INT(_kern_ipc, KIPC_SOMAXCONN, somaxconn, CTLFLAG_RW,
133     &somaxconn, 0, "Maximum pending socket connection queue size");
134 
135 static int use_soclose_fast = 1;
136 SYSCTL_INT(_kern_ipc, OID_AUTO, soclose_fast, CTLFLAG_RW,
137     &use_soclose_fast, 0, "Fast socket close");
138 
139 int use_soaccept_pred_fast = 1;
140 SYSCTL_INT(_kern_ipc, OID_AUTO, soaccept_pred_fast, CTLFLAG_RW,
141     &use_soaccept_pred_fast, 0, "Fast socket accept predication");
142 
143 int use_sendfile_async = 1;
144 SYSCTL_INT(_kern_ipc, OID_AUTO, sendfile_async, CTLFLAG_RW,
145     &use_sendfile_async, 0, "sendfile uses asynchronized pru_send");
146 
147 int use_soconnect_async = 1;
148 SYSCTL_INT(_kern_ipc, OID_AUTO, soconnect_async, CTLFLAG_RW,
149     &use_soconnect_async, 0, "soconnect uses asynchronized pru_connect");
150 
151 /*
152  * Socket operation routines.
153  * These routines are called by the routines in
154  * sys_socket.c or from a system process, and
155  * implement the semantics of socket operations by
156  * switching out to the protocol specific routines.
157  */
158 
159 /*
160  * Get a socket structure, and initialize it.
161  * Note that it would probably be better to allocate socket
162  * and PCB at the same time, but I'm not convinced that all
163  * the protocols can be easily modified to do this.
164  */
165 struct socket *
166 soalloc(int waitok, struct protosw *pr)
167 {
168 	struct socket *so;
169 	unsigned waitmask;
170 
171 	waitmask = waitok ? M_WAITOK : M_NOWAIT;
172 	so = kmalloc(sizeof(struct socket), M_SOCKET, M_ZERO|waitmask);
173 	if (so) {
174 		/* XXX race condition for reentrant kernel */
175 		so->so_proto = pr;
176 		TAILQ_INIT(&so->so_aiojobq);
177 		TAILQ_INIT(&so->so_rcv.ssb_kq.ki_mlist);
178 		TAILQ_INIT(&so->so_snd.ssb_kq.ki_mlist);
179 		lwkt_token_init(&so->so_rcv.ssb_token, "rcvtok");
180 		lwkt_token_init(&so->so_snd.ssb_token, "sndtok");
181 		spin_init(&so->so_rcvd_spin, "soalloc");
182 		netmsg_init(&so->so_rcvd_msg.base, so, &netisr_adone_rport,
183 		    MSGF_DROPABLE | MSGF_PRIORITY,
184 		    so->so_proto->pr_usrreqs->pru_rcvd);
185 		so->so_rcvd_msg.nm_pru_flags |= PRUR_ASYNC;
186 		so->so_state = SS_NOFDREF;
187 		so->so_refs = 1;
188 	}
189 	return so;
190 }
191 
192 int
193 socreate(int dom, struct socket **aso, int type,
194 	int proto, struct thread *td)
195 {
196 	struct proc *p = td->td_proc;
197 	struct protosw *prp;
198 	struct socket *so;
199 	struct pru_attach_info ai;
200 	int error;
201 
202 	if (proto)
203 		prp = pffindproto(dom, proto, type);
204 	else
205 		prp = pffindtype(dom, type);
206 
207 	if (prp == NULL || prp->pr_usrreqs->pru_attach == 0)
208 		return (EPROTONOSUPPORT);
209 
210 	if (p->p_ucred->cr_prison && jail_socket_unixiproute_only &&
211 	    prp->pr_domain->dom_family != PF_LOCAL &&
212 	    prp->pr_domain->dom_family != PF_INET &&
213 	    prp->pr_domain->dom_family != PF_INET6 &&
214 	    prp->pr_domain->dom_family != PF_ROUTE) {
215 		return (EPROTONOSUPPORT);
216 	}
217 
218 	if (prp->pr_type != type)
219 		return (EPROTOTYPE);
220 	so = soalloc(p != NULL, prp);
221 	if (so == NULL)
222 		return (ENOBUFS);
223 
224 	/*
225 	 * Callers of socreate() presumably will connect up a descriptor
226 	 * and call soclose() if they cannot.  This represents our so_refs
227 	 * (which should be 1) from soalloc().
228 	 */
229 	soclrstate(so, SS_NOFDREF);
230 
231 	/*
232 	 * Set a default port for protocol processing.  No action will occur
233 	 * on the socket on this port until an inpcb is attached to it and
234 	 * is able to match incoming packets, or until the socket becomes
235 	 * available to userland.
236 	 *
237 	 * We normally default the socket to the protocol thread on cpu 0,
238 	 * if protocol does not provide its own method to initialize the
239 	 * default port.
240 	 *
241 	 * If PR_SYNC_PORT is set (unix domain sockets) there is no protocol
242 	 * thread and all pr_*()/pru_*() calls are executed synchronously.
243 	 */
244 	if (prp->pr_flags & PR_SYNC_PORT)
245 		so->so_port = &netisr_sync_port;
246 	else if (prp->pr_initport != NULL)
247 		so->so_port = prp->pr_initport();
248 	else
249 		so->so_port = netisr_cpuport(0);
250 
251 	TAILQ_INIT(&so->so_incomp);
252 	TAILQ_INIT(&so->so_comp);
253 	so->so_type = type;
254 	so->so_cred = crhold(p->p_ucred);
255 	ai.sb_rlimit = &p->p_rlimit[RLIMIT_SBSIZE];
256 	ai.p_ucred = p->p_ucred;
257 	ai.fd_rdir = p->p_fd->fd_rdir;
258 
259 	/*
260 	 * Auto-sizing of socket buffers is managed by the protocols and
261 	 * the appropriate flags must be set in the pru_attach function.
262 	 */
263 	error = so_pru_attach(so, proto, &ai);
264 	if (error) {
265 		sosetstate(so, SS_NOFDREF);
266 		sofree(so);	/* from soalloc */
267 		return error;
268 	}
269 
270 	/*
271 	 * NOTE: Returns referenced socket.
272 	 */
273 	*aso = so;
274 	return (0);
275 }
276 
277 int
278 sobind(struct socket *so, struct sockaddr *nam, struct thread *td)
279 {
280 	int error;
281 
282 	error = so_pru_bind(so, nam, td);
283 	return (error);
284 }
285 
286 static void
287 sodealloc(struct socket *so)
288 {
289 	if (so->so_rcv.ssb_hiwat)
290 		(void)chgsbsize(so->so_cred->cr_uidinfo,
291 		    &so->so_rcv.ssb_hiwat, 0, RLIM_INFINITY);
292 	if (so->so_snd.ssb_hiwat)
293 		(void)chgsbsize(so->so_cred->cr_uidinfo,
294 		    &so->so_snd.ssb_hiwat, 0, RLIM_INFINITY);
295 #ifdef INET
296 	/* remove accept filter if present */
297 	if (so->so_accf != NULL)
298 		do_setopt_accept_filter(so, NULL);
299 #endif /* INET */
300 	crfree(so->so_cred);
301 	if (so->so_faddr != NULL)
302 		kfree(so->so_faddr, M_SONAME);
303 	kfree(so, M_SOCKET);
304 }
305 
306 int
307 solisten(struct socket *so, int backlog, struct thread *td)
308 {
309 	if (so->so_state & (SS_ISCONNECTED | SS_ISCONNECTING))
310 		return (EINVAL);
311 
312 	lwkt_gettoken(&so->so_rcv.ssb_token);
313 	if (TAILQ_EMPTY(&so->so_comp))
314 		so->so_options |= SO_ACCEPTCONN;
315 	lwkt_reltoken(&so->so_rcv.ssb_token);
316 	if (backlog < 0 || backlog > somaxconn)
317 		backlog = somaxconn;
318 	so->so_qlimit = backlog;
319 	return so_pru_listen(so, td);
320 }
321 
322 /*
323  * Destroy a disconnected socket.  This routine is a NOP if entities
324  * still have a reference on the socket:
325  *
326  *	so_pcb -	The protocol stack still has a reference
327  *	SS_NOFDREF -	There is no longer a file pointer reference
328  */
329 void
330 sofree(struct socket *so)
331 {
332 	struct socket *head;
333 
334 	/*
335 	 * This is a bit hackish at the moment.  We need to interlock
336 	 * any accept queue we are on before we potentially lose the
337 	 * last reference to avoid races against a re-reference from
338 	 * someone operating on the queue.
339 	 */
340 	while ((head = so->so_head) != NULL) {
341 		lwkt_getpooltoken(head);
342 		if (so->so_head == head)
343 			break;
344 		lwkt_relpooltoken(head);
345 	}
346 
347 	/*
348 	 * Arbitrage the last free.
349 	 */
350 	KKASSERT(so->so_refs > 0);
351 	if (atomic_fetchadd_int(&so->so_refs, -1) != 1) {
352 		if (head)
353 			lwkt_relpooltoken(head);
354 		return;
355 	}
356 
357 	KKASSERT(so->so_pcb == NULL && (so->so_state & SS_NOFDREF));
358 	KKASSERT((so->so_state & SS_ASSERTINPROG) == 0);
359 
360 	/*
361 	 * We're done, remove ourselves from the accept queue we are
362 	 * on, if we are on one.
363 	 */
364 	if (head != NULL) {
365 		if (so->so_state & SS_INCOMP) {
366 			TAILQ_REMOVE(&head->so_incomp, so, so_list);
367 			head->so_incqlen--;
368 		} else if (so->so_state & SS_COMP) {
369 			/*
370 			 * We must not decommission a socket that's
371 			 * on the accept(2) queue.  If we do, then
372 			 * accept(2) may hang after select(2) indicated
373 			 * that the listening socket was ready.
374 			 */
375 			lwkt_relpooltoken(head);
376 			return;
377 		} else {
378 			panic("sofree: not queued");
379 		}
380 		soclrstate(so, SS_INCOMP);
381 		so->so_head = NULL;
382 		lwkt_relpooltoken(head);
383 	}
384 	ssb_release(&so->so_snd, so);
385 	sorflush(so);
386 	sodealloc(so);
387 }
388 
389 /*
390  * Close a socket on last file table reference removal.
391  * Initiate disconnect if connected.
392  * Free socket when disconnect complete.
393  */
394 int
395 soclose(struct socket *so, int fflag)
396 {
397 	int error;
398 
399 	funsetown(&so->so_sigio);
400 	sosetstate(so, SS_ISCLOSING);
401 	if (!use_soclose_fast ||
402 	    (so->so_proto->pr_flags & PR_SYNC_PORT) ||
403 	    ((so->so_state & SS_ISCONNECTED) &&
404 	     (so->so_options & SO_LINGER))) {
405 		error = soclose_sync(so, fflag);
406 	} else {
407 		soclose_fast(so);
408 		error = 0;
409 	}
410 	return error;
411 }
412 
413 void
414 sodiscard(struct socket *so)
415 {
416 	lwkt_getpooltoken(so);
417 	if (so->so_options & SO_ACCEPTCONN) {
418 		struct socket *sp;
419 
420 		while ((sp = TAILQ_FIRST(&so->so_incomp)) != NULL) {
421 			TAILQ_REMOVE(&so->so_incomp, sp, so_list);
422 			so->so_incqlen--;
423 			soclrstate(sp, SS_INCOMP);
424 			soabort_async(sp, TRUE);
425 		}
426 		while ((sp = TAILQ_FIRST(&so->so_comp)) != NULL) {
427 			TAILQ_REMOVE(&so->so_comp, sp, so_list);
428 			so->so_qlen--;
429 			soclrstate(sp, SS_COMP);
430 			soabort_async(sp, TRUE);
431 		}
432 	}
433 	lwkt_relpooltoken(so);
434 
435 	if (so->so_state & SS_NOFDREF)
436 		panic("soclose: NOFDREF");
437 	sosetstate(so, SS_NOFDREF);	/* take ref */
438 }
439 
440 void
441 soinherit(struct socket *so, struct socket *so_inh)
442 {
443 	TAILQ_HEAD(, socket) comp, incomp;
444 	struct socket *sp;
445 	int qlen, incqlen;
446 
447 	KASSERT(so->so_options & SO_ACCEPTCONN,
448 	    ("so does not accept connection"));
449 	KASSERT(so_inh->so_options & SO_ACCEPTCONN,
450 	    ("so_inh does not accept connection"));
451 
452 	TAILQ_INIT(&comp);
453 	TAILQ_INIT(&incomp);
454 
455 	lwkt_getpooltoken(so);
456 	lwkt_getpooltoken(so_inh);
457 
458 	/*
459 	 * Save completed queue and incompleted queue
460 	 */
461 	TAILQ_CONCAT(&comp, &so->so_comp, so_list);
462 	qlen = so->so_qlen;
463 	so->so_qlen = 0;
464 
465 	TAILQ_CONCAT(&incomp, &so->so_incomp, so_list);
466 	incqlen = so->so_incqlen;
467 	so->so_incqlen = 0;
468 
469 	/*
470 	 * Append the saved completed queue and incompleted
471 	 * queue to the socket inherits them.
472 	 *
473 	 * XXX
474 	 * This may temporarily break the inheriting socket's
475 	 * so_qlimit.
476 	 */
477 	TAILQ_FOREACH(sp, &comp, so_list) {
478 		sp->so_head = so_inh;
479 		crfree(sp->so_cred);
480 		sp->so_cred = crhold(so_inh->so_cred);
481 	}
482 
483 	TAILQ_FOREACH(sp, &incomp, so_list) {
484 		sp->so_head = so_inh;
485 		crfree(sp->so_cred);
486 		sp->so_cred = crhold(so_inh->so_cred);
487 	}
488 
489 	TAILQ_CONCAT(&so_inh->so_comp, &comp, so_list);
490 	so_inh->so_qlen += qlen;
491 
492 	TAILQ_CONCAT(&so_inh->so_incomp, &incomp, so_list);
493 	so_inh->so_incqlen += incqlen;
494 
495 	lwkt_relpooltoken(so_inh);
496 	lwkt_relpooltoken(so);
497 
498 	if (qlen) {
499 		/*
500 		 * "New" connections have arrived
501 		 */
502 		sorwakeup(so_inh);
503 		wakeup(&so_inh->so_timeo);
504 	}
505 }
506 
507 static int
508 soclose_sync(struct socket *so, int fflag)
509 {
510 	int error = 0;
511 
512 	if (so->so_pcb == NULL)
513 		goto discard;
514 	if (so->so_state & SS_ISCONNECTED) {
515 		if ((so->so_state & SS_ISDISCONNECTING) == 0) {
516 			error = sodisconnect(so);
517 			if (error)
518 				goto drop;
519 		}
520 		if (so->so_options & SO_LINGER) {
521 			if ((so->so_state & SS_ISDISCONNECTING) &&
522 			    (fflag & FNONBLOCK))
523 				goto drop;
524 			while (so->so_state & SS_ISCONNECTED) {
525 				error = tsleep(&so->so_timeo, PCATCH,
526 					       "soclos", so->so_linger * hz);
527 				if (error)
528 					break;
529 			}
530 		}
531 	}
532 drop:
533 	if (so->so_pcb) {
534 		int error2;
535 
536 		error2 = so_pru_detach(so);
537 		if (error2 == EJUSTRETURN) {
538 			/*
539 			 * Protocol will call sodiscard()
540 			 * and sofree() for us.
541 			 */
542 			return error;
543 		}
544 		if (error == 0)
545 			error = error2;
546 	}
547 discard:
548 	sodiscard(so);
549 	so_pru_sync(so);	/* unpend async sending */
550 	sofree(so);		/* dispose of ref */
551 
552 	return (error);
553 }
554 
555 static void
556 soclose_sofree_async_handler(netmsg_t msg)
557 {
558 	sofree(msg->base.nm_so);
559 }
560 
561 static void
562 soclose_sofree_async(struct socket *so)
563 {
564 	struct netmsg_base *base = &so->so_clomsg;
565 
566 	netmsg_init(base, so, &netisr_apanic_rport, 0,
567 	    soclose_sofree_async_handler);
568 	lwkt_sendmsg(so->so_port, &base->lmsg);
569 }
570 
571 static void
572 soclose_disconn_async_handler(netmsg_t msg)
573 {
574 	struct socket *so = msg->base.nm_so;
575 
576 	if ((so->so_state & SS_ISCONNECTED) &&
577 	    (so->so_state & SS_ISDISCONNECTING) == 0)
578 		so_pru_disconnect_direct(so);
579 
580 	if (so->so_pcb) {
581 		int error;
582 
583 		error = so_pru_detach_direct(so);
584 		if (error == EJUSTRETURN) {
585 			/*
586 			 * Protocol will call sodiscard()
587 			 * and sofree() for us.
588 			 */
589 			return;
590 		}
591 	}
592 
593 	sodiscard(so);
594 	sofree(so);
595 }
596 
597 static void
598 soclose_disconn_async(struct socket *so)
599 {
600 	struct netmsg_base *base = &so->so_clomsg;
601 
602 	netmsg_init(base, so, &netisr_apanic_rport, 0,
603 	    soclose_disconn_async_handler);
604 	lwkt_sendmsg(so->so_port, &base->lmsg);
605 }
606 
607 static void
608 soclose_detach_async_handler(netmsg_t msg)
609 {
610 	struct socket *so = msg->base.nm_so;
611 
612 	if (so->so_pcb) {
613 		int error;
614 
615 		error = so_pru_detach_direct(so);
616 		if (error == EJUSTRETURN) {
617 			/*
618 			 * Protocol will call sodiscard()
619 			 * and sofree() for us.
620 			 */
621 			return;
622 		}
623 	}
624 
625 	sodiscard(so);
626 	sofree(so);
627 }
628 
629 static void
630 soclose_detach_async(struct socket *so)
631 {
632 	struct netmsg_base *base = &so->so_clomsg;
633 
634 	netmsg_init(base, so, &netisr_apanic_rport, 0,
635 	    soclose_detach_async_handler);
636 	lwkt_sendmsg(so->so_port, &base->lmsg);
637 }
638 
639 static void
640 soclose_fast(struct socket *so)
641 {
642 	if (so->so_pcb == NULL)
643 		goto discard;
644 
645 	if ((so->so_state & SS_ISCONNECTED) &&
646 	    (so->so_state & SS_ISDISCONNECTING) == 0) {
647 		soclose_disconn_async(so);
648 		return;
649 	}
650 
651 	if (so->so_pcb) {
652 		soclose_detach_async(so);
653 		return;
654 	}
655 
656 discard:
657 	sodiscard(so);
658 	soclose_sofree_async(so);
659 }
660 
661 /*
662  * Abort and destroy a socket.  Only one abort can be in progress
663  * at any given moment.
664  */
665 void
666 soabort_async(struct socket *so, boolean_t clr_head)
667 {
668 	/*
669 	 * Keep a reference before clearing the so_head
670 	 * to avoid racing socket close in netisr.
671 	 */
672 	soreference(so);
673 	if (clr_head)
674 		so->so_head = NULL;
675 	so_pru_abort_async(so);
676 }
677 
678 void
679 soabort_oncpu(struct socket *so)
680 {
681 	soreference(so);
682 	so_pru_abort_direct(so);
683 }
684 
685 /*
686  * so is passed in ref'd, which becomes owned by
687  * the cleared SS_NOFDREF flag.
688  */
689 void
690 soaccept_generic(struct socket *so)
691 {
692 	if ((so->so_state & SS_NOFDREF) == 0)
693 		panic("soaccept: !NOFDREF");
694 	soclrstate(so, SS_NOFDREF);	/* owned by lack of SS_NOFDREF */
695 }
696 
697 int
698 soaccept(struct socket *so, struct sockaddr **nam)
699 {
700 	int error;
701 
702 	soaccept_generic(so);
703 	error = so_pru_accept(so, nam);
704 	return (error);
705 }
706 
707 int
708 soconnect(struct socket *so, struct sockaddr *nam, struct thread *td,
709     boolean_t sync)
710 {
711 	int error;
712 
713 	if (so->so_options & SO_ACCEPTCONN)
714 		return (EOPNOTSUPP);
715 	/*
716 	 * If protocol is connection-based, can only connect once.
717 	 * Otherwise, if connected, try to disconnect first.
718 	 * This allows user to disconnect by connecting to, e.g.,
719 	 * a null address.
720 	 */
721 	if (so->so_state & (SS_ISCONNECTED|SS_ISCONNECTING) &&
722 	    ((so->so_proto->pr_flags & PR_CONNREQUIRED) ||
723 	    (error = sodisconnect(so)))) {
724 		error = EISCONN;
725 	} else {
726 		/*
727 		 * Prevent accumulated error from previous connection
728 		 * from biting us.
729 		 */
730 		so->so_error = 0;
731 		if (!sync && so->so_proto->pr_usrreqs->pru_preconnect)
732 			error = so_pru_connect_async(so, nam, td);
733 		else
734 			error = so_pru_connect(so, nam, td);
735 	}
736 	return (error);
737 }
738 
739 int
740 soconnect2(struct socket *so1, struct socket *so2)
741 {
742 	int error;
743 
744 	error = so_pru_connect2(so1, so2);
745 	return (error);
746 }
747 
748 int
749 sodisconnect(struct socket *so)
750 {
751 	int error;
752 
753 	if ((so->so_state & SS_ISCONNECTED) == 0) {
754 		error = ENOTCONN;
755 		goto bad;
756 	}
757 	if (so->so_state & SS_ISDISCONNECTING) {
758 		error = EALREADY;
759 		goto bad;
760 	}
761 	error = so_pru_disconnect(so);
762 bad:
763 	return (error);
764 }
765 
766 #define	SBLOCKWAIT(f)	(((f) & MSG_DONTWAIT) ? M_NOWAIT : M_WAITOK)
767 /*
768  * Send on a socket.
769  * If send must go all at once and message is larger than
770  * send buffering, then hard error.
771  * Lock against other senders.
772  * If must go all at once and not enough room now, then
773  * inform user that this would block and do nothing.
774  * Otherwise, if nonblocking, send as much as possible.
775  * The data to be sent is described by "uio" if nonzero,
776  * otherwise by the mbuf chain "top" (which must be null
777  * if uio is not).  Data provided in mbuf chain must be small
778  * enough to send all at once.
779  *
780  * Returns nonzero on error, timeout or signal; callers
781  * must check for short counts if EINTR/ERESTART are returned.
782  * Data and control buffers are freed on return.
783  */
784 int
785 sosend(struct socket *so, struct sockaddr *addr, struct uio *uio,
786 	struct mbuf *top, struct mbuf *control, int flags,
787 	struct thread *td)
788 {
789 	struct mbuf **mp;
790 	struct mbuf *m;
791 	size_t resid;
792 	int space, len;
793 	int clen = 0, error, dontroute, mlen;
794 	int atomic = sosendallatonce(so) || top;
795 	int pru_flags;
796 
797 	if (uio) {
798 		resid = uio->uio_resid;
799 	} else {
800 		resid = (size_t)top->m_pkthdr.len;
801 #ifdef INVARIANTS
802 		len = 0;
803 		for (m = top; m; m = m->m_next)
804 			len += m->m_len;
805 		KKASSERT(top->m_pkthdr.len == len);
806 #endif
807 	}
808 
809 	/*
810 	 * WARNING!  resid is unsigned, space and len are signed.  space
811 	 * 	     can wind up negative if the sockbuf is overcommitted.
812 	 *
813 	 * Also check to make sure that MSG_EOR isn't used on SOCK_STREAM
814 	 * type sockets since that's an error.
815 	 */
816 	if (so->so_type == SOCK_STREAM && (flags & MSG_EOR)) {
817 		error = EINVAL;
818 		goto out;
819 	}
820 
821 	dontroute =
822 	    (flags & MSG_DONTROUTE) && (so->so_options & SO_DONTROUTE) == 0 &&
823 	    (so->so_proto->pr_flags & PR_ATOMIC);
824 	if (td->td_lwp != NULL)
825 		td->td_lwp->lwp_ru.ru_msgsnd++;
826 	if (control)
827 		clen = control->m_len;
828 #define	gotoerr(errcode)	{ error = errcode; goto release; }
829 
830 restart:
831 	error = ssb_lock(&so->so_snd, SBLOCKWAIT(flags));
832 	if (error)
833 		goto out;
834 
835 	do {
836 		if (so->so_state & SS_CANTSENDMORE)
837 			gotoerr(EPIPE);
838 		if (so->so_error) {
839 			error = so->so_error;
840 			so->so_error = 0;
841 			goto release;
842 		}
843 		if ((so->so_state & SS_ISCONNECTED) == 0) {
844 			/*
845 			 * `sendto' and `sendmsg' is allowed on a connection-
846 			 * based socket if it supports implied connect.
847 			 * Return ENOTCONN if not connected and no address is
848 			 * supplied.
849 			 */
850 			if ((so->so_proto->pr_flags & PR_CONNREQUIRED) &&
851 			    (so->so_proto->pr_flags & PR_IMPLOPCL) == 0) {
852 				if ((so->so_state & SS_ISCONFIRMING) == 0 &&
853 				    !(resid == 0 && clen != 0))
854 					gotoerr(ENOTCONN);
855 			} else if (addr == NULL)
856 			    gotoerr(so->so_proto->pr_flags & PR_CONNREQUIRED ?
857 				   ENOTCONN : EDESTADDRREQ);
858 		}
859 		if ((atomic && resid > so->so_snd.ssb_hiwat) ||
860 		    clen > so->so_snd.ssb_hiwat) {
861 			gotoerr(EMSGSIZE);
862 		}
863 		space = ssb_space(&so->so_snd);
864 		if (flags & MSG_OOB)
865 			space += 1024;
866 		if ((space < 0 || (size_t)space < resid + clen) && uio &&
867 		    (atomic || space < so->so_snd.ssb_lowat || space < clen)) {
868 			if (flags & (MSG_FNONBLOCKING|MSG_DONTWAIT))
869 				gotoerr(EWOULDBLOCK);
870 			ssb_unlock(&so->so_snd);
871 			error = ssb_wait(&so->so_snd);
872 			if (error)
873 				goto out;
874 			goto restart;
875 		}
876 		mp = &top;
877 		space -= clen;
878 		do {
879 		    if (uio == NULL) {
880 			/*
881 			 * Data is prepackaged in "top".
882 			 */
883 			resid = 0;
884 			if (flags & MSG_EOR)
885 				top->m_flags |= M_EOR;
886 		    } else do {
887 			if (resid > INT_MAX)
888 				resid = INT_MAX;
889 			m = m_getl((int)resid, M_WAITOK, MT_DATA,
890 				   top == NULL ? M_PKTHDR : 0, &mlen);
891 			if (top == NULL) {
892 				m->m_pkthdr.len = 0;
893 				m->m_pkthdr.rcvif = NULL;
894 			}
895 			len = imin((int)szmin(mlen, resid), space);
896 			if (resid < MINCLSIZE) {
897 				/*
898 				 * For datagram protocols, leave room
899 				 * for protocol headers in first mbuf.
900 				 */
901 				if (atomic && top == NULL && len < mlen)
902 					MH_ALIGN(m, len);
903 			}
904 			space -= len;
905 			error = uiomove(mtod(m, caddr_t), (size_t)len, uio);
906 			resid = uio->uio_resid;
907 			m->m_len = len;
908 			*mp = m;
909 			top->m_pkthdr.len += len;
910 			if (error)
911 				goto release;
912 			mp = &m->m_next;
913 			if (resid == 0) {
914 				if (flags & MSG_EOR)
915 					top->m_flags |= M_EOR;
916 				break;
917 			}
918 		    } while (space > 0 && atomic);
919 		    if (dontroute)
920 			    so->so_options |= SO_DONTROUTE;
921 		    if (flags & MSG_OOB) {
922 		    	    pru_flags = PRUS_OOB;
923 		    } else if ((flags & MSG_EOF) &&
924 		    	       (so->so_proto->pr_flags & PR_IMPLOPCL) &&
925 			       (resid == 0)) {
926 			    /*
927 			     * If the user set MSG_EOF, the protocol
928 			     * understands this flag and nothing left to
929 			     * send then use PRU_SEND_EOF instead of PRU_SEND.
930 			     */
931 		    	    pru_flags = PRUS_EOF;
932 		    } else if (resid > 0 && space > 0) {
933 			    /* If there is more to send, set PRUS_MORETOCOME */
934 		    	    pru_flags = PRUS_MORETOCOME;
935 		    } else {
936 		    	    pru_flags = 0;
937 		    }
938 		    /*
939 		     * XXX all the SS_CANTSENDMORE checks previously
940 		     * done could be out of date.  We could have recieved
941 		     * a reset packet in an interrupt or maybe we slept
942 		     * while doing page faults in uiomove() etc. We could
943 		     * probably recheck again inside the splnet() protection
944 		     * here, but there are probably other places that this
945 		     * also happens.  We must rethink this.
946 		     */
947 		    error = so_pru_send(so, pru_flags, top, addr, control, td);
948 		    if (dontroute)
949 			    so->so_options &= ~SO_DONTROUTE;
950 		    clen = 0;
951 		    control = NULL;
952 		    top = NULL;
953 		    mp = &top;
954 		    if (error)
955 			    goto release;
956 		} while (resid && space > 0);
957 	} while (resid);
958 
959 release:
960 	ssb_unlock(&so->so_snd);
961 out:
962 	if (top)
963 		m_freem(top);
964 	if (control)
965 		m_freem(control);
966 	return (error);
967 }
968 
969 #ifdef INET
970 /*
971  * A specialization of sosend() for UDP based on protocol-specific knowledge:
972  *   so->so_proto->pr_flags has the PR_ATOMIC field set.  This means that
973  *	sosendallatonce() returns true,
974  *	the "atomic" variable is true,
975  *	and sosendudp() blocks until space is available for the entire send.
976  *   so->so_proto->pr_flags does not have the PR_CONNREQUIRED or
977  *	PR_IMPLOPCL flags set.
978  *   UDP has no out-of-band data.
979  *   UDP has no control data.
980  *   UDP does not support MSG_EOR.
981  */
982 int
983 sosendudp(struct socket *so, struct sockaddr *addr, struct uio *uio,
984 	  struct mbuf *top, struct mbuf *control, int flags, struct thread *td)
985 {
986 	size_t resid;
987 	int error, pru_flags = 0;
988 	int space;
989 
990 	if (td->td_lwp != NULL)
991 		td->td_lwp->lwp_ru.ru_msgsnd++;
992 	if (control)
993 		m_freem(control);
994 
995 	KASSERT((uio && !top) || (top && !uio), ("bad arguments to sosendudp"));
996 	resid = uio ? uio->uio_resid : (size_t)top->m_pkthdr.len;
997 
998 restart:
999 	error = ssb_lock(&so->so_snd, SBLOCKWAIT(flags));
1000 	if (error)
1001 		goto out;
1002 
1003 	if (so->so_state & SS_CANTSENDMORE)
1004 		gotoerr(EPIPE);
1005 	if (so->so_error) {
1006 		error = so->so_error;
1007 		so->so_error = 0;
1008 		goto release;
1009 	}
1010 	if (!(so->so_state & SS_ISCONNECTED) && addr == NULL)
1011 		gotoerr(EDESTADDRREQ);
1012 	if (resid > so->so_snd.ssb_hiwat)
1013 		gotoerr(EMSGSIZE);
1014 	space = ssb_space(&so->so_snd);
1015 	if (uio && (space < 0 || (size_t)space < resid)) {
1016 		if (flags & (MSG_FNONBLOCKING|MSG_DONTWAIT))
1017 			gotoerr(EWOULDBLOCK);
1018 		ssb_unlock(&so->so_snd);
1019 		error = ssb_wait(&so->so_snd);
1020 		if (error)
1021 			goto out;
1022 		goto restart;
1023 	}
1024 
1025 	if (uio) {
1026 		int hdrlen = max_hdr;
1027 
1028 		/*
1029 		 * We try to optimize out the additional mbuf
1030 		 * allocations in M_PREPEND() on output path, e.g.
1031 		 * - udp_output(), when it tries to prepend protocol
1032 		 *   headers.
1033 		 * - Link layer output function, when it tries to
1034 		 *   prepend link layer header.
1035 		 *
1036 		 * This probably will not benefit any data that will
1037 		 * be fragmented, so this optimization is only performed
1038 		 * when the size of data and max size of protocol+link
1039 		 * headers fit into one mbuf cluster.
1040 		 */
1041 		if (uio->uio_resid > MCLBYTES - hdrlen ||
1042 		    !udp_sosend_prepend) {
1043 			top = m_uiomove(uio);
1044 			if (top == NULL)
1045 				goto release;
1046 		} else {
1047 			int nsize;
1048 
1049 			top = m_getl(uio->uio_resid + hdrlen, M_WAITOK,
1050 			    MT_DATA, M_PKTHDR, &nsize);
1051 			KASSERT(nsize >= uio->uio_resid + hdrlen,
1052 			    ("sosendudp invalid nsize %d, "
1053 			     "resid %zu, hdrlen %d",
1054 			     nsize, uio->uio_resid, hdrlen));
1055 
1056 			top->m_len = uio->uio_resid;
1057 			top->m_pkthdr.len = uio->uio_resid;
1058 			top->m_data += hdrlen;
1059 
1060 			error = uiomove(mtod(top, caddr_t), top->m_len, uio);
1061 			if (error)
1062 				goto out;
1063 		}
1064 	}
1065 
1066 	if (flags & MSG_DONTROUTE)
1067 		pru_flags |= PRUS_DONTROUTE;
1068 
1069 	if (udp_sosend_async && (flags & MSG_SYNC) == 0) {
1070 		so_pru_send_async(so, pru_flags, top, addr, NULL, td);
1071 		error = 0;
1072 	} else {
1073 		error = so_pru_send(so, pru_flags, top, addr, NULL, td);
1074 	}
1075 	top = NULL;		/* sent or freed in lower layer */
1076 
1077 release:
1078 	ssb_unlock(&so->so_snd);
1079 out:
1080 	if (top)
1081 		m_freem(top);
1082 	return (error);
1083 }
1084 
1085 int
1086 sosendtcp(struct socket *so, struct sockaddr *addr, struct uio *uio,
1087 	struct mbuf *top, struct mbuf *control, int flags,
1088 	struct thread *td)
1089 {
1090 	struct mbuf **mp;
1091 	struct mbuf *m;
1092 	size_t resid;
1093 	int space, len;
1094 	int error, mlen;
1095 	int allatonce;
1096 	int pru_flags;
1097 
1098 	if (uio) {
1099 		KKASSERT(top == NULL);
1100 		allatonce = 0;
1101 		resid = uio->uio_resid;
1102 	} else {
1103 		allatonce = 1;
1104 		resid = (size_t)top->m_pkthdr.len;
1105 #ifdef INVARIANTS
1106 		len = 0;
1107 		for (m = top; m; m = m->m_next)
1108 			len += m->m_len;
1109 		KKASSERT(top->m_pkthdr.len == len);
1110 #endif
1111 	}
1112 
1113 	/*
1114 	 * WARNING!  resid is unsigned, space and len are signed.  space
1115 	 * 	     can wind up negative if the sockbuf is overcommitted.
1116 	 *
1117 	 * Also check to make sure that MSG_EOR isn't used on TCP
1118 	 */
1119 	if (flags & MSG_EOR) {
1120 		error = EINVAL;
1121 		goto out;
1122 	}
1123 
1124 	if (control) {
1125 		/* TCP doesn't do control messages (rights, creds, etc) */
1126 		if (control->m_len) {
1127 			error = EINVAL;
1128 			goto out;
1129 		}
1130 		m_freem(control);	/* empty control, just free it */
1131 		control = NULL;
1132 	}
1133 
1134 	if (td->td_lwp != NULL)
1135 		td->td_lwp->lwp_ru.ru_msgsnd++;
1136 
1137 #define	gotoerr(errcode)	{ error = errcode; goto release; }
1138 
1139 restart:
1140 	error = ssb_lock(&so->so_snd, SBLOCKWAIT(flags));
1141 	if (error)
1142 		goto out;
1143 
1144 	do {
1145 		if (so->so_state & SS_CANTSENDMORE)
1146 			gotoerr(EPIPE);
1147 		if (so->so_error) {
1148 			error = so->so_error;
1149 			so->so_error = 0;
1150 			goto release;
1151 		}
1152 		if ((so->so_state & SS_ISCONNECTED) == 0 &&
1153 		    (so->so_state & SS_ISCONFIRMING) == 0)
1154 			gotoerr(ENOTCONN);
1155 		if (allatonce && resid > so->so_snd.ssb_hiwat)
1156 			gotoerr(EMSGSIZE);
1157 
1158 		space = ssb_space_prealloc(&so->so_snd);
1159 		if (flags & MSG_OOB)
1160 			space += 1024;
1161 		if ((space < 0 || (size_t)space < resid) && !allatonce &&
1162 		    space < so->so_snd.ssb_lowat) {
1163 			if (flags & (MSG_FNONBLOCKING|MSG_DONTWAIT))
1164 				gotoerr(EWOULDBLOCK);
1165 			ssb_unlock(&so->so_snd);
1166 			error = ssb_wait(&so->so_snd);
1167 			if (error)
1168 				goto out;
1169 			goto restart;
1170 		}
1171 		mp = &top;
1172 		do {
1173 		    int cnt = 0, async = 0;
1174 
1175 		    if (uio == NULL) {
1176 			/*
1177 			 * Data is prepackaged in "top".
1178 			 */
1179 			resid = 0;
1180 		    } else do {
1181 			if (resid > INT_MAX)
1182 				resid = INT_MAX;
1183 			if (tcp_sosend_jcluster) {
1184 				m = m_getlj((int)resid, M_WAITOK, MT_DATA,
1185 					   top == NULL ? M_PKTHDR : 0, &mlen);
1186 			} else {
1187 				m = m_getl((int)resid, M_WAITOK, MT_DATA,
1188 					   top == NULL ? M_PKTHDR : 0, &mlen);
1189 			}
1190 			if (top == NULL) {
1191 				m->m_pkthdr.len = 0;
1192 				m->m_pkthdr.rcvif = NULL;
1193 			}
1194 			len = imin((int)szmin(mlen, resid), space);
1195 			space -= len;
1196 			error = uiomove(mtod(m, caddr_t), (size_t)len, uio);
1197 			resid = uio->uio_resid;
1198 			m->m_len = len;
1199 			*mp = m;
1200 			top->m_pkthdr.len += len;
1201 			if (error)
1202 				goto release;
1203 			mp = &m->m_next;
1204 			if (resid == 0)
1205 				break;
1206 			++cnt;
1207 		    } while (space > 0 && cnt < tcp_sosend_agglim);
1208 
1209 		    if (tcp_sosend_async)
1210 			    async = 1;
1211 
1212 		    if (flags & MSG_OOB) {
1213 		    	    pru_flags = PRUS_OOB;
1214 			    async = 0;
1215 		    } else if ((flags & MSG_EOF) && resid == 0) {
1216 			    pru_flags = PRUS_EOF;
1217 		    } else if (resid > 0 && space > 0) {
1218 			    /* If there is more to send, set PRUS_MORETOCOME */
1219 		    	    pru_flags = PRUS_MORETOCOME;
1220 			    async = 1;
1221 		    } else {
1222 		    	    pru_flags = 0;
1223 		    }
1224 
1225 		    if (flags & MSG_SYNC)
1226 			    async = 0;
1227 
1228 		    /*
1229 		     * XXX all the SS_CANTSENDMORE checks previously
1230 		     * done could be out of date.  We could have recieved
1231 		     * a reset packet in an interrupt or maybe we slept
1232 		     * while doing page faults in uiomove() etc. We could
1233 		     * probably recheck again inside the splnet() protection
1234 		     * here, but there are probably other places that this
1235 		     * also happens.  We must rethink this.
1236 		     */
1237 		    for (m = top; m; m = m->m_next)
1238 			    ssb_preallocstream(&so->so_snd, m);
1239 		    if (!async) {
1240 			    error = so_pru_send(so, pru_flags, top,
1241 			        NULL, NULL, td);
1242 		    } else {
1243 			    so_pru_send_async(so, pru_flags, top,
1244 			        NULL, NULL, td);
1245 			    error = 0;
1246 		    }
1247 
1248 		    top = NULL;
1249 		    mp = &top;
1250 		    if (error)
1251 			    goto release;
1252 		} while (resid && space > 0);
1253 	} while (resid);
1254 
1255 release:
1256 	ssb_unlock(&so->so_snd);
1257 out:
1258 	if (top)
1259 		m_freem(top);
1260 	if (control)
1261 		m_freem(control);
1262 	return (error);
1263 }
1264 #endif
1265 
1266 /*
1267  * Implement receive operations on a socket.
1268  *
1269  * We depend on the way that records are added to the signalsockbuf
1270  * by sbappend*.  In particular, each record (mbufs linked through m_next)
1271  * must begin with an address if the protocol so specifies,
1272  * followed by an optional mbuf or mbufs containing ancillary data,
1273  * and then zero or more mbufs of data.
1274  *
1275  * Although the signalsockbuf is locked, new data may still be appended.
1276  * A token inside the ssb_lock deals with MP issues and still allows
1277  * the network to access the socket if we block in a uio.
1278  *
1279  * The caller may receive the data as a single mbuf chain by supplying
1280  * an mbuf **mp0 for use in returning the chain.  The uio is then used
1281  * only for the count in uio_resid.
1282  */
1283 int
1284 soreceive(struct socket *so, struct sockaddr **psa, struct uio *uio,
1285 	  struct sockbuf *sio, struct mbuf **controlp, int *flagsp)
1286 {
1287 	struct mbuf *m, *n;
1288 	struct mbuf *free_chain = NULL;
1289 	int flags, len, error, offset;
1290 	struct protosw *pr = so->so_proto;
1291 	int moff, type = 0;
1292 	size_t resid, orig_resid;
1293 
1294 	if (uio)
1295 		resid = uio->uio_resid;
1296 	else
1297 		resid = (size_t)(sio->sb_climit - sio->sb_cc);
1298 	orig_resid = resid;
1299 
1300 	if (psa)
1301 		*psa = NULL;
1302 	if (controlp)
1303 		*controlp = NULL;
1304 	if (flagsp)
1305 		flags = *flagsp &~ MSG_EOR;
1306 	else
1307 		flags = 0;
1308 	if (flags & MSG_OOB) {
1309 		m = m_get(M_WAITOK, MT_DATA);
1310 		if (m == NULL)
1311 			return (ENOBUFS);
1312 		error = so_pru_rcvoob(so, m, flags & MSG_PEEK);
1313 		if (error)
1314 			goto bad;
1315 		if (sio) {
1316 			do {
1317 				sbappend(sio, m);
1318 				KKASSERT(resid >= (size_t)m->m_len);
1319 				resid -= (size_t)m->m_len;
1320 			} while (resid > 0 && m);
1321 		} else {
1322 			do {
1323 				uio->uio_resid = resid;
1324 				error = uiomove(mtod(m, caddr_t),
1325 						(int)szmin(resid, m->m_len),
1326 						uio);
1327 				resid = uio->uio_resid;
1328 				m = m_free(m);
1329 			} while (uio->uio_resid && error == 0 && m);
1330 		}
1331 bad:
1332 		if (m)
1333 			m_freem(m);
1334 		return (error);
1335 	}
1336 	if ((so->so_state & SS_ISCONFIRMING) && resid)
1337 		so_pru_rcvd(so, 0);
1338 
1339 	/*
1340 	 * The token interlocks against the protocol thread while
1341 	 * ssb_lock is a blocking lock against other userland entities.
1342 	 */
1343 	lwkt_gettoken(&so->so_rcv.ssb_token);
1344 restart:
1345 	error = ssb_lock(&so->so_rcv, SBLOCKWAIT(flags));
1346 	if (error)
1347 		goto done;
1348 
1349 	m = so->so_rcv.ssb_mb;
1350 	/*
1351 	 * If we have less data than requested, block awaiting more
1352 	 * (subject to any timeout) if:
1353 	 *   1. the current count is less than the low water mark, or
1354 	 *   2. MSG_WAITALL is set, and it is possible to do the entire
1355 	 *	receive operation at once if we block (resid <= hiwat).
1356 	 *   3. MSG_DONTWAIT is not set
1357 	 * If MSG_WAITALL is set but resid is larger than the receive buffer,
1358 	 * we have to do the receive in sections, and thus risk returning
1359 	 * a short count if a timeout or signal occurs after we start.
1360 	 */
1361 	if (m == NULL || (((flags & MSG_DONTWAIT) == 0 &&
1362 	    (size_t)so->so_rcv.ssb_cc < resid) &&
1363 	    (so->so_rcv.ssb_cc < so->so_rcv.ssb_lowat ||
1364 	    ((flags & MSG_WAITALL) && resid <= (size_t)so->so_rcv.ssb_hiwat)) &&
1365 	    m->m_nextpkt == 0 && (pr->pr_flags & PR_ATOMIC) == 0)) {
1366 		KASSERT(m != NULL || !so->so_rcv.ssb_cc, ("receive 1"));
1367 		if (so->so_error) {
1368 			if (m)
1369 				goto dontblock;
1370 			error = so->so_error;
1371 			if ((flags & MSG_PEEK) == 0)
1372 				so->so_error = 0;
1373 			goto release;
1374 		}
1375 		if (so->so_state & SS_CANTRCVMORE) {
1376 			if (m)
1377 				goto dontblock;
1378 			else
1379 				goto release;
1380 		}
1381 		for (; m; m = m->m_next) {
1382 			if (m->m_type == MT_OOBDATA  || (m->m_flags & M_EOR)) {
1383 				m = so->so_rcv.ssb_mb;
1384 				goto dontblock;
1385 			}
1386 		}
1387 		if ((so->so_state & (SS_ISCONNECTED|SS_ISCONNECTING)) == 0 &&
1388 		    (pr->pr_flags & PR_CONNREQUIRED)) {
1389 			error = ENOTCONN;
1390 			goto release;
1391 		}
1392 		if (resid == 0)
1393 			goto release;
1394 		if (flags & (MSG_FNONBLOCKING|MSG_DONTWAIT)) {
1395 			error = EWOULDBLOCK;
1396 			goto release;
1397 		}
1398 		ssb_unlock(&so->so_rcv);
1399 		error = ssb_wait(&so->so_rcv);
1400 		if (error)
1401 			goto done;
1402 		goto restart;
1403 	}
1404 dontblock:
1405 	if (uio && uio->uio_td && uio->uio_td->td_proc)
1406 		uio->uio_td->td_lwp->lwp_ru.ru_msgrcv++;
1407 
1408 	/*
1409 	 * note: m should be == sb_mb here.  Cache the next record while
1410 	 * cleaning up.  Note that calling m_free*() will break out critical
1411 	 * section.
1412 	 */
1413 	KKASSERT(m == so->so_rcv.ssb_mb);
1414 
1415 	/*
1416 	 * Skip any address mbufs prepending the record.
1417 	 */
1418 	if (pr->pr_flags & PR_ADDR) {
1419 		KASSERT(m->m_type == MT_SONAME, ("receive 1a"));
1420 		orig_resid = 0;
1421 		if (psa)
1422 			*psa = dup_sockaddr(mtod(m, struct sockaddr *));
1423 		if (flags & MSG_PEEK)
1424 			m = m->m_next;
1425 		else
1426 			m = sbunlinkmbuf(&so->so_rcv.sb, m, &free_chain);
1427 	}
1428 
1429 	/*
1430 	 * Skip any control mbufs prepending the record.
1431 	 */
1432 	while (m && m->m_type == MT_CONTROL && error == 0) {
1433 		if (flags & MSG_PEEK) {
1434 			if (controlp)
1435 				*controlp = m_copy(m, 0, m->m_len);
1436 			m = m->m_next;	/* XXX race */
1437 		} else {
1438 			if (controlp) {
1439 				n = sbunlinkmbuf(&so->so_rcv.sb, m, NULL);
1440 				if (pr->pr_domain->dom_externalize &&
1441 				    mtod(m, struct cmsghdr *)->cmsg_type ==
1442 				    SCM_RIGHTS)
1443 				   error = (*pr->pr_domain->dom_externalize)(m);
1444 				*controlp = m;
1445 				m = n;
1446 			} else {
1447 				m = sbunlinkmbuf(&so->so_rcv.sb, m, &free_chain);
1448 			}
1449 		}
1450 		if (controlp && *controlp) {
1451 			orig_resid = 0;
1452 			controlp = &(*controlp)->m_next;
1453 		}
1454 	}
1455 
1456 	/*
1457 	 * flag OOB data.
1458 	 */
1459 	if (m) {
1460 		type = m->m_type;
1461 		if (type == MT_OOBDATA)
1462 			flags |= MSG_OOB;
1463 	}
1464 
1465 	/*
1466 	 * Copy to the UIO or mbuf return chain (*mp).
1467 	 */
1468 	moff = 0;
1469 	offset = 0;
1470 	while (m && resid > 0 && error == 0) {
1471 		if (m->m_type == MT_OOBDATA) {
1472 			if (type != MT_OOBDATA)
1473 				break;
1474 		} else if (type == MT_OOBDATA)
1475 			break;
1476 		else
1477 		    KASSERT(m->m_type == MT_DATA || m->m_type == MT_HEADER,
1478 			("receive 3"));
1479 		soclrstate(so, SS_RCVATMARK);
1480 		len = (resid > INT_MAX) ? INT_MAX : resid;
1481 		if (so->so_oobmark && len > so->so_oobmark - offset)
1482 			len = so->so_oobmark - offset;
1483 		if (len > m->m_len - moff)
1484 			len = m->m_len - moff;
1485 
1486 		/*
1487 		 * Copy out to the UIO or pass the mbufs back to the SIO.
1488 		 * The SIO is dealt with when we eat the mbuf, but deal
1489 		 * with the resid here either way.
1490 		 */
1491 		if (uio) {
1492 			uio->uio_resid = resid;
1493 			error = uiomove(mtod(m, caddr_t) + moff, len, uio);
1494 			resid = uio->uio_resid;
1495 			if (error)
1496 				goto release;
1497 		} else {
1498 			resid -= (size_t)len;
1499 		}
1500 
1501 		/*
1502 		 * Eat the entire mbuf or just a piece of it
1503 		 */
1504 		if (len == m->m_len - moff) {
1505 			if (m->m_flags & M_EOR)
1506 				flags |= MSG_EOR;
1507 			if (flags & MSG_PEEK) {
1508 				m = m->m_next;
1509 				moff = 0;
1510 			} else {
1511 				if (sio) {
1512 					n = sbunlinkmbuf(&so->so_rcv.sb, m, NULL);
1513 					sbappend(sio, m);
1514 					m = n;
1515 				} else {
1516 					m = sbunlinkmbuf(&so->so_rcv.sb, m, &free_chain);
1517 				}
1518 			}
1519 		} else {
1520 			if (flags & MSG_PEEK) {
1521 				moff += len;
1522 			} else {
1523 				if (sio) {
1524 					n = m_copym(m, 0, len, M_WAITOK);
1525 					if (n)
1526 						sbappend(sio, n);
1527 				}
1528 				m->m_data += len;
1529 				m->m_len -= len;
1530 				so->so_rcv.ssb_cc -= len;
1531 			}
1532 		}
1533 		if (so->so_oobmark) {
1534 			if ((flags & MSG_PEEK) == 0) {
1535 				so->so_oobmark -= len;
1536 				if (so->so_oobmark == 0) {
1537 					sosetstate(so, SS_RCVATMARK);
1538 					break;
1539 				}
1540 			} else {
1541 				offset += len;
1542 				if (offset == so->so_oobmark)
1543 					break;
1544 			}
1545 		}
1546 		if (flags & MSG_EOR)
1547 			break;
1548 		/*
1549 		 * If the MSG_WAITALL flag is set (for non-atomic socket),
1550 		 * we must not quit until resid == 0 or an error
1551 		 * termination.  If a signal/timeout occurs, return
1552 		 * with a short count but without error.
1553 		 * Keep signalsockbuf locked against other readers.
1554 		 */
1555 		while ((flags & MSG_WAITALL) && m == NULL &&
1556 		       resid > 0 && !sosendallatonce(so) &&
1557 		       so->so_rcv.ssb_mb == NULL) {
1558 			if (so->so_error || so->so_state & SS_CANTRCVMORE)
1559 				break;
1560 			/*
1561 			 * The window might have closed to zero, make
1562 			 * sure we send an ack now that we've drained
1563 			 * the buffer or we might end up blocking until
1564 			 * the idle takes over (5 seconds).
1565 			 */
1566 			if (pr->pr_flags & PR_WANTRCVD && so->so_pcb)
1567 				so_pru_rcvd(so, flags);
1568 			error = ssb_wait(&so->so_rcv);
1569 			if (error) {
1570 				ssb_unlock(&so->so_rcv);
1571 				error = 0;
1572 				goto done;
1573 			}
1574 			m = so->so_rcv.ssb_mb;
1575 		}
1576 	}
1577 
1578 	/*
1579 	 * If an atomic read was requested but unread data still remains
1580 	 * in the record, set MSG_TRUNC.
1581 	 */
1582 	if (m && pr->pr_flags & PR_ATOMIC)
1583 		flags |= MSG_TRUNC;
1584 
1585 	/*
1586 	 * Cleanup.  If an atomic read was requested drop any unread data.
1587 	 */
1588 	if ((flags & MSG_PEEK) == 0) {
1589 		if (m && (pr->pr_flags & PR_ATOMIC))
1590 			sbdroprecord(&so->so_rcv.sb);
1591 		if ((pr->pr_flags & PR_WANTRCVD) && so->so_pcb)
1592 			so_pru_rcvd(so, flags);
1593 	}
1594 
1595 	if (orig_resid == resid && orig_resid &&
1596 	    (flags & MSG_EOR) == 0 && (so->so_state & SS_CANTRCVMORE) == 0) {
1597 		ssb_unlock(&so->so_rcv);
1598 		goto restart;
1599 	}
1600 
1601 	if (flagsp)
1602 		*flagsp |= flags;
1603 release:
1604 	ssb_unlock(&so->so_rcv);
1605 done:
1606 	lwkt_reltoken(&so->so_rcv.ssb_token);
1607 	if (free_chain)
1608 		m_freem(free_chain);
1609 	return (error);
1610 }
1611 
1612 int
1613 sorecvtcp(struct socket *so, struct sockaddr **psa, struct uio *uio,
1614 	  struct sockbuf *sio, struct mbuf **controlp, int *flagsp)
1615 {
1616 	struct mbuf *m, *n;
1617 	struct mbuf *free_chain = NULL;
1618 	int flags, len, error, offset;
1619 	struct protosw *pr = so->so_proto;
1620 	int moff;
1621 	int didoob;
1622 	size_t resid, orig_resid, restmp;
1623 
1624 	if (uio)
1625 		resid = uio->uio_resid;
1626 	else
1627 		resid = (size_t)(sio->sb_climit - sio->sb_cc);
1628 	orig_resid = resid;
1629 
1630 	if (psa)
1631 		*psa = NULL;
1632 	if (controlp)
1633 		*controlp = NULL;
1634 	if (flagsp)
1635 		flags = *flagsp &~ MSG_EOR;
1636 	else
1637 		flags = 0;
1638 	if (flags & MSG_OOB) {
1639 		m = m_get(M_WAITOK, MT_DATA);
1640 		if (m == NULL)
1641 			return (ENOBUFS);
1642 		error = so_pru_rcvoob(so, m, flags & MSG_PEEK);
1643 		if (error)
1644 			goto bad;
1645 		if (sio) {
1646 			do {
1647 				sbappend(sio, m);
1648 				KKASSERT(resid >= (size_t)m->m_len);
1649 				resid -= (size_t)m->m_len;
1650 			} while (resid > 0 && m);
1651 		} else {
1652 			do {
1653 				uio->uio_resid = resid;
1654 				error = uiomove(mtod(m, caddr_t),
1655 						(int)szmin(resid, m->m_len),
1656 						uio);
1657 				resid = uio->uio_resid;
1658 				m = m_free(m);
1659 			} while (uio->uio_resid && error == 0 && m);
1660 		}
1661 bad:
1662 		if (m)
1663 			m_freem(m);
1664 		return (error);
1665 	}
1666 
1667 	/*
1668 	 * The token interlocks against the protocol thread while
1669 	 * ssb_lock is a blocking lock against other userland entities.
1670 	 *
1671 	 * Lock a limited number of mbufs (not all, so sbcompress() still
1672 	 * works well).  The token is used as an interlock for sbwait() so
1673 	 * release it afterwords.
1674 	 */
1675 restart:
1676 	error = ssb_lock(&so->so_rcv, SBLOCKWAIT(flags));
1677 	if (error)
1678 		goto done;
1679 
1680 	lwkt_gettoken(&so->so_rcv.ssb_token);
1681 	m = so->so_rcv.ssb_mb;
1682 
1683 	/*
1684 	 * If we have less data than requested, block awaiting more
1685 	 * (subject to any timeout) if:
1686 	 *   1. the current count is less than the low water mark, or
1687 	 *   2. MSG_WAITALL is set, and it is possible to do the entire
1688 	 *	receive operation at once if we block (resid <= hiwat).
1689 	 *   3. MSG_DONTWAIT is not set
1690 	 * If MSG_WAITALL is set but resid is larger than the receive buffer,
1691 	 * we have to do the receive in sections, and thus risk returning
1692 	 * a short count if a timeout or signal occurs after we start.
1693 	 */
1694 	if (m == NULL || (((flags & MSG_DONTWAIT) == 0 &&
1695 	    (size_t)so->so_rcv.ssb_cc < resid) &&
1696 	    (so->so_rcv.ssb_cc < so->so_rcv.ssb_lowat ||
1697 	   ((flags & MSG_WAITALL) && resid <= (size_t)so->so_rcv.ssb_hiwat)))) {
1698 		KASSERT(m != NULL || !so->so_rcv.ssb_cc, ("receive 1"));
1699 		if (so->so_error) {
1700 			if (m)
1701 				goto dontblock;
1702 			lwkt_reltoken(&so->so_rcv.ssb_token);
1703 			error = so->so_error;
1704 			if ((flags & MSG_PEEK) == 0)
1705 				so->so_error = 0;
1706 			goto release;
1707 		}
1708 		if (so->so_state & SS_CANTRCVMORE) {
1709 			if (m)
1710 				goto dontblock;
1711 			lwkt_reltoken(&so->so_rcv.ssb_token);
1712 			goto release;
1713 		}
1714 		if ((so->so_state & (SS_ISCONNECTED|SS_ISCONNECTING)) == 0 &&
1715 		    (pr->pr_flags & PR_CONNREQUIRED)) {
1716 			lwkt_reltoken(&so->so_rcv.ssb_token);
1717 			error = ENOTCONN;
1718 			goto release;
1719 		}
1720 		if (resid == 0) {
1721 			lwkt_reltoken(&so->so_rcv.ssb_token);
1722 			goto release;
1723 		}
1724 		if (flags & (MSG_FNONBLOCKING|MSG_DONTWAIT)) {
1725 			lwkt_reltoken(&so->so_rcv.ssb_token);
1726 			error = EWOULDBLOCK;
1727 			goto release;
1728 		}
1729 		ssb_unlock(&so->so_rcv);
1730 		error = ssb_wait(&so->so_rcv);
1731 		lwkt_reltoken(&so->so_rcv.ssb_token);
1732 		if (error)
1733 			goto done;
1734 		goto restart;
1735 	}
1736 
1737 	/*
1738 	 * Token still held
1739 	 */
1740 dontblock:
1741 	n = m;
1742 	restmp = 0;
1743 	while (n && restmp < resid) {
1744 		n->m_flags |= M_SOLOCKED;
1745 		restmp += n->m_len;
1746 		if (n->m_next == NULL)
1747 			n = n->m_nextpkt;
1748 		else
1749 			n = n->m_next;
1750 	}
1751 
1752 	/*
1753 	 * Release token for loop
1754 	 */
1755 	lwkt_reltoken(&so->so_rcv.ssb_token);
1756 	if (uio && uio->uio_td && uio->uio_td->td_proc)
1757 		uio->uio_td->td_lwp->lwp_ru.ru_msgrcv++;
1758 
1759 	/*
1760 	 * note: m should be == sb_mb here.  Cache the next record while
1761 	 * cleaning up.  Note that calling m_free*() will break out critical
1762 	 * section.
1763 	 */
1764 	KKASSERT(m == so->so_rcv.ssb_mb);
1765 
1766 	/*
1767 	 * Copy to the UIO or mbuf return chain (*mp).
1768 	 *
1769 	 * NOTE: Token is not held for loop
1770 	 */
1771 	moff = 0;
1772 	offset = 0;
1773 	didoob = 0;
1774 
1775 	while (m && (m->m_flags & M_SOLOCKED) && resid > 0 && error == 0) {
1776 		KASSERT(m->m_type == MT_DATA || m->m_type == MT_HEADER,
1777 		    ("receive 3"));
1778 
1779 		soclrstate(so, SS_RCVATMARK);
1780 		len = (resid > INT_MAX) ? INT_MAX : resid;
1781 		if (so->so_oobmark && len > so->so_oobmark - offset)
1782 			len = so->so_oobmark - offset;
1783 		if (len > m->m_len - moff)
1784 			len = m->m_len - moff;
1785 
1786 		/*
1787 		 * Copy out to the UIO or pass the mbufs back to the SIO.
1788 		 * The SIO is dealt with when we eat the mbuf, but deal
1789 		 * with the resid here either way.
1790 		 */
1791 		if (uio) {
1792 			uio->uio_resid = resid;
1793 			error = uiomove(mtod(m, caddr_t) + moff, len, uio);
1794 			resid = uio->uio_resid;
1795 			if (error)
1796 				goto release;
1797 		} else {
1798 			resid -= (size_t)len;
1799 		}
1800 
1801 		/*
1802 		 * Eat the entire mbuf or just a piece of it
1803 		 */
1804 		offset += len;
1805 		if (len == m->m_len - moff) {
1806 			m = m->m_next;
1807 			moff = 0;
1808 		} else {
1809 			moff += len;
1810 		}
1811 
1812 		/*
1813 		 * Check oobmark
1814 		 */
1815 		if (so->so_oobmark && offset == so->so_oobmark) {
1816 			didoob = 1;
1817 			break;
1818 		}
1819 	}
1820 
1821 	/*
1822 	 * Synchronize sockbuf with data we read.
1823 	 *
1824 	 * NOTE: (m) is junk on entry (it could be left over from the
1825 	 *	 previous loop).
1826 	 */
1827 	if ((flags & MSG_PEEK) == 0) {
1828 		lwkt_gettoken(&so->so_rcv.ssb_token);
1829 		m = so->so_rcv.ssb_mb;
1830 		while (m && offset >= m->m_len) {
1831 			if (so->so_oobmark) {
1832 				so->so_oobmark -= m->m_len;
1833 				if (so->so_oobmark == 0) {
1834 					sosetstate(so, SS_RCVATMARK);
1835 					didoob = 1;
1836 				}
1837 			}
1838 			offset -= m->m_len;
1839 			if (sio) {
1840 				n = sbunlinkmbuf(&so->so_rcv.sb, m, NULL);
1841 				sbappend(sio, m);
1842 				m = n;
1843 			} else {
1844 				m = sbunlinkmbuf(&so->so_rcv.sb,
1845 						 m, &free_chain);
1846 			}
1847 		}
1848 		if (offset) {
1849 			KKASSERT(m);
1850 			if (sio) {
1851 				n = m_copym(m, 0, offset, M_WAITOK);
1852 				if (n)
1853 					sbappend(sio, n);
1854 			}
1855 			m->m_data += offset;
1856 			m->m_len -= offset;
1857 			so->so_rcv.ssb_cc -= offset;
1858 			if (so->so_oobmark) {
1859 				so->so_oobmark -= offset;
1860 				if (so->so_oobmark == 0) {
1861 					sosetstate(so, SS_RCVATMARK);
1862 					didoob = 1;
1863 				}
1864 			}
1865 			offset = 0;
1866 		}
1867 		lwkt_reltoken(&so->so_rcv.ssb_token);
1868 	}
1869 
1870 	/*
1871 	 * If the MSG_WAITALL flag is set (for non-atomic socket),
1872 	 * we must not quit until resid == 0 or an error termination.
1873 	 *
1874 	 * If a signal/timeout occurs, return with a short count but without
1875 	 * error.
1876 	 *
1877 	 * Keep signalsockbuf locked against other readers.
1878 	 *
1879 	 * XXX if MSG_PEEK we currently do quit.
1880 	 */
1881 	if ((flags & MSG_WAITALL) && !(flags & MSG_PEEK) &&
1882 	    didoob == 0 && resid > 0 &&
1883 	    !sosendallatonce(so)) {
1884 		lwkt_gettoken(&so->so_rcv.ssb_token);
1885 		error = 0;
1886 		while ((m = so->so_rcv.ssb_mb) == NULL) {
1887 			if (so->so_error || (so->so_state & SS_CANTRCVMORE)) {
1888 				error = so->so_error;
1889 				break;
1890 			}
1891 			/*
1892 			 * The window might have closed to zero, make
1893 			 * sure we send an ack now that we've drained
1894 			 * the buffer or we might end up blocking until
1895 			 * the idle takes over (5 seconds).
1896 			 */
1897 			if (so->so_pcb)
1898 				so_pru_rcvd_async(so);
1899 			if (so->so_rcv.ssb_mb == NULL)
1900 				error = ssb_wait(&so->so_rcv);
1901 			if (error) {
1902 				lwkt_reltoken(&so->so_rcv.ssb_token);
1903 				ssb_unlock(&so->so_rcv);
1904 				error = 0;
1905 				goto done;
1906 			}
1907 		}
1908 		if (m && error == 0)
1909 			goto dontblock;
1910 		lwkt_reltoken(&so->so_rcv.ssb_token);
1911 	}
1912 
1913 	/*
1914 	 * Token not held here.
1915 	 *
1916 	 * Cleanup.  If an atomic read was requested drop any unread data XXX
1917 	 */
1918 	if ((flags & MSG_PEEK) == 0) {
1919 		if (so->so_pcb)
1920 			so_pru_rcvd_async(so);
1921 	}
1922 
1923 	if (orig_resid == resid && orig_resid &&
1924 	    (so->so_state & SS_CANTRCVMORE) == 0) {
1925 		ssb_unlock(&so->so_rcv);
1926 		goto restart;
1927 	}
1928 
1929 	if (flagsp)
1930 		*flagsp |= flags;
1931 release:
1932 	ssb_unlock(&so->so_rcv);
1933 done:
1934 	if (free_chain)
1935 		m_freem(free_chain);
1936 	return (error);
1937 }
1938 
1939 /*
1940  * Shut a socket down.  Note that we do not get a frontend lock as we
1941  * want to be able to shut the socket down even if another thread is
1942  * blocked in a read(), thus waking it up.
1943  */
1944 int
1945 soshutdown(struct socket *so, int how)
1946 {
1947 	if (!(how == SHUT_RD || how == SHUT_WR || how == SHUT_RDWR))
1948 		return (EINVAL);
1949 
1950 	if (how != SHUT_WR) {
1951 		/*ssb_lock(&so->so_rcv, M_WAITOK);*/
1952 		sorflush(so);
1953 		/*ssb_unlock(&so->so_rcv);*/
1954 	}
1955 	if (how != SHUT_RD)
1956 		return (so_pru_shutdown(so));
1957 	return (0);
1958 }
1959 
1960 void
1961 sorflush(struct socket *so)
1962 {
1963 	struct signalsockbuf *ssb = &so->so_rcv;
1964 	struct protosw *pr = so->so_proto;
1965 	struct signalsockbuf asb;
1966 
1967 	atomic_set_int(&ssb->ssb_flags, SSB_NOINTR);
1968 
1969 	lwkt_gettoken(&ssb->ssb_token);
1970 	socantrcvmore(so);
1971 	asb = *ssb;
1972 
1973 	/*
1974 	 * Can't just blow up the ssb structure here
1975 	 */
1976 	bzero(&ssb->sb, sizeof(ssb->sb));
1977 	ssb->ssb_timeo = 0;
1978 	ssb->ssb_lowat = 0;
1979 	ssb->ssb_hiwat = 0;
1980 	ssb->ssb_mbmax = 0;
1981 	atomic_clear_int(&ssb->ssb_flags, SSB_CLEAR_MASK);
1982 
1983 	if ((pr->pr_flags & PR_RIGHTS) && pr->pr_domain->dom_dispose)
1984 		(*pr->pr_domain->dom_dispose)(asb.ssb_mb);
1985 	ssb_release(&asb, so);
1986 
1987 	lwkt_reltoken(&ssb->ssb_token);
1988 }
1989 
1990 #ifdef INET
1991 static int
1992 do_setopt_accept_filter(struct socket *so, struct sockopt *sopt)
1993 {
1994 	struct accept_filter_arg	*afap = NULL;
1995 	struct accept_filter	*afp;
1996 	struct so_accf	*af = so->so_accf;
1997 	int	error = 0;
1998 
1999 	/* do not set/remove accept filters on non listen sockets */
2000 	if ((so->so_options & SO_ACCEPTCONN) == 0) {
2001 		error = EINVAL;
2002 		goto out;
2003 	}
2004 
2005 	/* removing the filter */
2006 	if (sopt == NULL) {
2007 		if (af != NULL) {
2008 			if (af->so_accept_filter != NULL &&
2009 				af->so_accept_filter->accf_destroy != NULL) {
2010 				af->so_accept_filter->accf_destroy(so);
2011 			}
2012 			if (af->so_accept_filter_str != NULL) {
2013 				kfree(af->so_accept_filter_str, M_ACCF);
2014 			}
2015 			kfree(af, M_ACCF);
2016 			so->so_accf = NULL;
2017 		}
2018 		so->so_options &= ~SO_ACCEPTFILTER;
2019 		return (0);
2020 	}
2021 	/* adding a filter */
2022 	/* must remove previous filter first */
2023 	if (af != NULL) {
2024 		error = EINVAL;
2025 		goto out;
2026 	}
2027 	/* don't put large objects on the kernel stack */
2028 	afap = kmalloc(sizeof(*afap), M_TEMP, M_WAITOK);
2029 	error = sooptcopyin(sopt, afap, sizeof *afap, sizeof *afap);
2030 	afap->af_name[sizeof(afap->af_name)-1] = '\0';
2031 	afap->af_arg[sizeof(afap->af_arg)-1] = '\0';
2032 	if (error)
2033 		goto out;
2034 	afp = accept_filt_get(afap->af_name);
2035 	if (afp == NULL) {
2036 		error = ENOENT;
2037 		goto out;
2038 	}
2039 	af = kmalloc(sizeof(*af), M_ACCF, M_WAITOK | M_ZERO);
2040 	if (afp->accf_create != NULL) {
2041 		if (afap->af_name[0] != '\0') {
2042 			int len = strlen(afap->af_name) + 1;
2043 
2044 			af->so_accept_filter_str = kmalloc(len, M_ACCF,
2045 							   M_WAITOK);
2046 			strcpy(af->so_accept_filter_str, afap->af_name);
2047 		}
2048 		af->so_accept_filter_arg = afp->accf_create(so, afap->af_arg);
2049 		if (af->so_accept_filter_arg == NULL) {
2050 			kfree(af->so_accept_filter_str, M_ACCF);
2051 			kfree(af, M_ACCF);
2052 			so->so_accf = NULL;
2053 			error = EINVAL;
2054 			goto out;
2055 		}
2056 	}
2057 	af->so_accept_filter = afp;
2058 	so->so_accf = af;
2059 	so->so_options |= SO_ACCEPTFILTER;
2060 out:
2061 	if (afap != NULL)
2062 		kfree(afap, M_TEMP);
2063 	return (error);
2064 }
2065 #endif /* INET */
2066 
2067 /*
2068  * Perhaps this routine, and sooptcopyout(), below, ought to come in
2069  * an additional variant to handle the case where the option value needs
2070  * to be some kind of integer, but not a specific size.
2071  * In addition to their use here, these functions are also called by the
2072  * protocol-level pr_ctloutput() routines.
2073  */
2074 int
2075 sooptcopyin(struct sockopt *sopt, void *buf, size_t len, size_t minlen)
2076 {
2077 	return soopt_to_kbuf(sopt, buf, len, minlen);
2078 }
2079 
2080 int
2081 soopt_to_kbuf(struct sockopt *sopt, void *buf, size_t len, size_t minlen)
2082 {
2083 	size_t	valsize;
2084 
2085 	KKASSERT(!sopt->sopt_val || kva_p(sopt->sopt_val));
2086 	KKASSERT(kva_p(buf));
2087 
2088 	/*
2089 	 * If the user gives us more than we wanted, we ignore it,
2090 	 * but if we don't get the minimum length the caller
2091 	 * wants, we return EINVAL.  On success, sopt->sopt_valsize
2092 	 * is set to however much we actually retrieved.
2093 	 */
2094 	if ((valsize = sopt->sopt_valsize) < minlen)
2095 		return EINVAL;
2096 	if (valsize > len)
2097 		sopt->sopt_valsize = valsize = len;
2098 
2099 	bcopy(sopt->sopt_val, buf, valsize);
2100 	return 0;
2101 }
2102 
2103 
2104 int
2105 sosetopt(struct socket *so, struct sockopt *sopt)
2106 {
2107 	int	error, optval;
2108 	struct	linger l;
2109 	struct	timeval tv;
2110 	u_long  val;
2111 	struct signalsockbuf *sotmp;
2112 
2113 	error = 0;
2114 	sopt->sopt_dir = SOPT_SET;
2115 	if (sopt->sopt_level != SOL_SOCKET) {
2116 		if (so->so_proto && so->so_proto->pr_ctloutput) {
2117 			return (so_pr_ctloutput(so, sopt));
2118 		}
2119 		error = ENOPROTOOPT;
2120 	} else {
2121 		switch (sopt->sopt_name) {
2122 #ifdef INET
2123 		case SO_ACCEPTFILTER:
2124 			error = do_setopt_accept_filter(so, sopt);
2125 			if (error)
2126 				goto bad;
2127 			break;
2128 #endif /* INET */
2129 		case SO_LINGER:
2130 			error = sooptcopyin(sopt, &l, sizeof l, sizeof l);
2131 			if (error)
2132 				goto bad;
2133 
2134 			so->so_linger = l.l_linger;
2135 			if (l.l_onoff)
2136 				so->so_options |= SO_LINGER;
2137 			else
2138 				so->so_options &= ~SO_LINGER;
2139 			break;
2140 
2141 		case SO_DEBUG:
2142 		case SO_KEEPALIVE:
2143 		case SO_DONTROUTE:
2144 		case SO_USELOOPBACK:
2145 		case SO_BROADCAST:
2146 		case SO_REUSEADDR:
2147 		case SO_REUSEPORT:
2148 		case SO_OOBINLINE:
2149 		case SO_TIMESTAMP:
2150 		case SO_NOSIGPIPE:
2151 			error = sooptcopyin(sopt, &optval, sizeof optval,
2152 					    sizeof optval);
2153 			if (error)
2154 				goto bad;
2155 			if (optval)
2156 				so->so_options |= sopt->sopt_name;
2157 			else
2158 				so->so_options &= ~sopt->sopt_name;
2159 			break;
2160 
2161 		case SO_SNDBUF:
2162 		case SO_RCVBUF:
2163 		case SO_SNDLOWAT:
2164 		case SO_RCVLOWAT:
2165 			error = sooptcopyin(sopt, &optval, sizeof optval,
2166 					    sizeof optval);
2167 			if (error)
2168 				goto bad;
2169 
2170 			/*
2171 			 * Values < 1 make no sense for any of these
2172 			 * options, so disallow them.
2173 			 */
2174 			if (optval < 1) {
2175 				error = EINVAL;
2176 				goto bad;
2177 			}
2178 
2179 			switch (sopt->sopt_name) {
2180 			case SO_SNDBUF:
2181 			case SO_RCVBUF:
2182 				if (ssb_reserve(sopt->sopt_name == SO_SNDBUF ?
2183 				    &so->so_snd : &so->so_rcv, (u_long)optval,
2184 				    so,
2185 				    &curproc->p_rlimit[RLIMIT_SBSIZE]) == 0) {
2186 					error = ENOBUFS;
2187 					goto bad;
2188 				}
2189 				sotmp = (sopt->sopt_name == SO_SNDBUF) ?
2190 						&so->so_snd : &so->so_rcv;
2191 				atomic_clear_int(&sotmp->ssb_flags,
2192 						 SSB_AUTOSIZE);
2193 				break;
2194 
2195 			/*
2196 			 * Make sure the low-water is never greater than
2197 			 * the high-water.
2198 			 */
2199 			case SO_SNDLOWAT:
2200 				so->so_snd.ssb_lowat =
2201 				    (optval > so->so_snd.ssb_hiwat) ?
2202 				    so->so_snd.ssb_hiwat : optval;
2203 				atomic_clear_int(&so->so_snd.ssb_flags,
2204 						 SSB_AUTOLOWAT);
2205 				break;
2206 			case SO_RCVLOWAT:
2207 				so->so_rcv.ssb_lowat =
2208 				    (optval > so->so_rcv.ssb_hiwat) ?
2209 				    so->so_rcv.ssb_hiwat : optval;
2210 				atomic_clear_int(&so->so_rcv.ssb_flags,
2211 						 SSB_AUTOLOWAT);
2212 				break;
2213 			}
2214 			break;
2215 
2216 		case SO_SNDTIMEO:
2217 		case SO_RCVTIMEO:
2218 			error = sooptcopyin(sopt, &tv, sizeof tv,
2219 					    sizeof tv);
2220 			if (error)
2221 				goto bad;
2222 
2223 			/* assert(hz > 0); */
2224 			if (tv.tv_sec < 0 || tv.tv_sec > INT_MAX / hz ||
2225 			    tv.tv_usec < 0 || tv.tv_usec >= 1000000) {
2226 				error = EDOM;
2227 				goto bad;
2228 			}
2229 			/* assert(tick > 0); */
2230 			/* assert(ULONG_MAX - INT_MAX >= 1000000); */
2231 			val = (u_long)(tv.tv_sec * hz) + tv.tv_usec / ustick;
2232 			if (val > INT_MAX) {
2233 				error = EDOM;
2234 				goto bad;
2235 			}
2236 			if (val == 0 && tv.tv_usec != 0)
2237 				val = 1;
2238 
2239 			switch (sopt->sopt_name) {
2240 			case SO_SNDTIMEO:
2241 				so->so_snd.ssb_timeo = val;
2242 				break;
2243 			case SO_RCVTIMEO:
2244 				so->so_rcv.ssb_timeo = val;
2245 				break;
2246 			}
2247 			break;
2248 		default:
2249 			error = ENOPROTOOPT;
2250 			break;
2251 		}
2252 		if (error == 0 && so->so_proto && so->so_proto->pr_ctloutput) {
2253 			(void) so_pr_ctloutput(so, sopt);
2254 		}
2255 	}
2256 bad:
2257 	return (error);
2258 }
2259 
2260 /* Helper routine for getsockopt */
2261 int
2262 sooptcopyout(struct sockopt *sopt, const void *buf, size_t len)
2263 {
2264 	soopt_from_kbuf(sopt, buf, len);
2265 	return 0;
2266 }
2267 
2268 void
2269 soopt_from_kbuf(struct sockopt *sopt, const void *buf, size_t len)
2270 {
2271 	size_t	valsize;
2272 
2273 	if (len == 0) {
2274 		sopt->sopt_valsize = 0;
2275 		return;
2276 	}
2277 
2278 	KKASSERT(!sopt->sopt_val || kva_p(sopt->sopt_val));
2279 	KKASSERT(kva_p(buf));
2280 
2281 	/*
2282 	 * Documented get behavior is that we always return a value,
2283 	 * possibly truncated to fit in the user's buffer.
2284 	 * Traditional behavior is that we always tell the user
2285 	 * precisely how much we copied, rather than something useful
2286 	 * like the total amount we had available for her.
2287 	 * Note that this interface is not idempotent; the entire answer must
2288 	 * generated ahead of time.
2289 	 */
2290 	valsize = szmin(len, sopt->sopt_valsize);
2291 	sopt->sopt_valsize = valsize;
2292 	if (sopt->sopt_val != 0) {
2293 		bcopy(buf, sopt->sopt_val, valsize);
2294 	}
2295 }
2296 
2297 int
2298 sogetopt(struct socket *so, struct sockopt *sopt)
2299 {
2300 	int	error, optval;
2301 	long	optval_l;
2302 	struct	linger l;
2303 	struct	timeval tv;
2304 #ifdef INET
2305 	struct accept_filter_arg *afap;
2306 #endif
2307 
2308 	error = 0;
2309 	sopt->sopt_dir = SOPT_GET;
2310 	if (sopt->sopt_level != SOL_SOCKET) {
2311 		if (so->so_proto && so->so_proto->pr_ctloutput) {
2312 			return (so_pr_ctloutput(so, sopt));
2313 		} else
2314 			return (ENOPROTOOPT);
2315 	} else {
2316 		switch (sopt->sopt_name) {
2317 #ifdef INET
2318 		case SO_ACCEPTFILTER:
2319 			if ((so->so_options & SO_ACCEPTCONN) == 0)
2320 				return (EINVAL);
2321 			afap = kmalloc(sizeof(*afap), M_TEMP,
2322 				       M_WAITOK | M_ZERO);
2323 			if ((so->so_options & SO_ACCEPTFILTER) != 0) {
2324 				strcpy(afap->af_name, so->so_accf->so_accept_filter->accf_name);
2325 				if (so->so_accf->so_accept_filter_str != NULL)
2326 					strcpy(afap->af_arg, so->so_accf->so_accept_filter_str);
2327 			}
2328 			error = sooptcopyout(sopt, afap, sizeof(*afap));
2329 			kfree(afap, M_TEMP);
2330 			break;
2331 #endif /* INET */
2332 
2333 		case SO_LINGER:
2334 			l.l_onoff = so->so_options & SO_LINGER;
2335 			l.l_linger = so->so_linger;
2336 			error = sooptcopyout(sopt, &l, sizeof l);
2337 			break;
2338 
2339 		case SO_USELOOPBACK:
2340 		case SO_DONTROUTE:
2341 		case SO_DEBUG:
2342 		case SO_KEEPALIVE:
2343 		case SO_REUSEADDR:
2344 		case SO_REUSEPORT:
2345 		case SO_BROADCAST:
2346 		case SO_OOBINLINE:
2347 		case SO_TIMESTAMP:
2348 		case SO_NOSIGPIPE:
2349 			optval = so->so_options & sopt->sopt_name;
2350 integer:
2351 			error = sooptcopyout(sopt, &optval, sizeof optval);
2352 			break;
2353 
2354 		case SO_TYPE:
2355 			optval = so->so_type;
2356 			goto integer;
2357 
2358 		case SO_ERROR:
2359 			optval = so->so_error;
2360 			so->so_error = 0;
2361 			goto integer;
2362 
2363 		case SO_SNDBUF:
2364 			optval = so->so_snd.ssb_hiwat;
2365 			goto integer;
2366 
2367 		case SO_RCVBUF:
2368 			optval = so->so_rcv.ssb_hiwat;
2369 			goto integer;
2370 
2371 		case SO_SNDLOWAT:
2372 			optval = so->so_snd.ssb_lowat;
2373 			goto integer;
2374 
2375 		case SO_RCVLOWAT:
2376 			optval = so->so_rcv.ssb_lowat;
2377 			goto integer;
2378 
2379 		case SO_SNDTIMEO:
2380 		case SO_RCVTIMEO:
2381 			optval = (sopt->sopt_name == SO_SNDTIMEO ?
2382 				  so->so_snd.ssb_timeo : so->so_rcv.ssb_timeo);
2383 
2384 			tv.tv_sec = optval / hz;
2385 			tv.tv_usec = (optval % hz) * ustick;
2386 			error = sooptcopyout(sopt, &tv, sizeof tv);
2387 			break;
2388 
2389 		case SO_SNDSPACE:
2390 			optval_l = ssb_space(&so->so_snd);
2391 			error = sooptcopyout(sopt, &optval_l, sizeof(optval_l));
2392 			break;
2393 
2394 		case SO_CPUHINT:
2395 			optval = -1; /* no hint */
2396 			goto integer;
2397 
2398 		default:
2399 			error = ENOPROTOOPT;
2400 			break;
2401 		}
2402 		if (error == 0 && so->so_proto && so->so_proto->pr_ctloutput)
2403 			so_pr_ctloutput(so, sopt);
2404 		return (error);
2405 	}
2406 }
2407 
2408 /* XXX; prepare mbuf for (__FreeBSD__ < 3) routines. */
2409 int
2410 soopt_getm(struct sockopt *sopt, struct mbuf **mp)
2411 {
2412 	struct mbuf *m, *m_prev;
2413 	int sopt_size = sopt->sopt_valsize, msize;
2414 
2415 	m = m_getl(sopt_size, sopt->sopt_td ? M_WAITOK : M_NOWAIT, MT_DATA,
2416 		   0, &msize);
2417 	if (m == NULL)
2418 		return (ENOBUFS);
2419 	m->m_len = min(msize, sopt_size);
2420 	sopt_size -= m->m_len;
2421 	*mp = m;
2422 	m_prev = m;
2423 
2424 	while (sopt_size > 0) {
2425 		m = m_getl(sopt_size, sopt->sopt_td ? M_WAITOK : M_NOWAIT,
2426 			   MT_DATA, 0, &msize);
2427 		if (m == NULL) {
2428 			m_freem(*mp);
2429 			return (ENOBUFS);
2430 		}
2431 		m->m_len = min(msize, sopt_size);
2432 		sopt_size -= m->m_len;
2433 		m_prev->m_next = m;
2434 		m_prev = m;
2435 	}
2436 	return (0);
2437 }
2438 
2439 /* XXX; copyin sopt data into mbuf chain for (__FreeBSD__ < 3) routines. */
2440 int
2441 soopt_mcopyin(struct sockopt *sopt, struct mbuf *m)
2442 {
2443 	soopt_to_mbuf(sopt, m);
2444 	return 0;
2445 }
2446 
2447 void
2448 soopt_to_mbuf(struct sockopt *sopt, struct mbuf *m)
2449 {
2450 	size_t valsize;
2451 	void *val;
2452 
2453 	KKASSERT(!sopt->sopt_val || kva_p(sopt->sopt_val));
2454 	KKASSERT(kva_p(m));
2455 	if (sopt->sopt_val == NULL)
2456 		return;
2457 	val = sopt->sopt_val;
2458 	valsize = sopt->sopt_valsize;
2459 	while (m != NULL && valsize >= m->m_len) {
2460 		bcopy(val, mtod(m, char *), m->m_len);
2461 		valsize -= m->m_len;
2462 		val = (caddr_t)val + m->m_len;
2463 		m = m->m_next;
2464 	}
2465 	if (m != NULL) /* should be allocated enoughly at ip6_sooptmcopyin() */
2466 		panic("ip6_sooptmcopyin");
2467 }
2468 
2469 /* XXX; copyout mbuf chain data into soopt for (__FreeBSD__ < 3) routines. */
2470 int
2471 soopt_mcopyout(struct sockopt *sopt, struct mbuf *m)
2472 {
2473 	return soopt_from_mbuf(sopt, m);
2474 }
2475 
2476 int
2477 soopt_from_mbuf(struct sockopt *sopt, struct mbuf *m)
2478 {
2479 	struct mbuf *m0 = m;
2480 	size_t valsize = 0;
2481 	size_t maxsize;
2482 	void *val;
2483 
2484 	KKASSERT(!sopt->sopt_val || kva_p(sopt->sopt_val));
2485 	KKASSERT(kva_p(m));
2486 	if (sopt->sopt_val == NULL)
2487 		return 0;
2488 	val = sopt->sopt_val;
2489 	maxsize = sopt->sopt_valsize;
2490 	while (m != NULL && maxsize >= m->m_len) {
2491 		bcopy(mtod(m, char *), val, m->m_len);
2492 	       maxsize -= m->m_len;
2493 	       val = (caddr_t)val + m->m_len;
2494 	       valsize += m->m_len;
2495 	       m = m->m_next;
2496 	}
2497 	if (m != NULL) {
2498 		/* enough soopt buffer should be given from user-land */
2499 		m_freem(m0);
2500 		return (EINVAL);
2501 	}
2502 	sopt->sopt_valsize = valsize;
2503 	return 0;
2504 }
2505 
2506 void
2507 sohasoutofband(struct socket *so)
2508 {
2509 	if (so->so_sigio != NULL)
2510 		pgsigio(so->so_sigio, SIGURG, 0);
2511 	KNOTE(&so->so_rcv.ssb_kq.ki_note, NOTE_OOB);
2512 }
2513 
2514 int
2515 sokqfilter(struct file *fp, struct knote *kn)
2516 {
2517 	struct socket *so = (struct socket *)kn->kn_fp->f_data;
2518 	struct signalsockbuf *ssb;
2519 
2520 	switch (kn->kn_filter) {
2521 	case EVFILT_READ:
2522 		if (so->so_options & SO_ACCEPTCONN)
2523 			kn->kn_fop = &solisten_filtops;
2524 		else
2525 			kn->kn_fop = &soread_filtops;
2526 		ssb = &so->so_rcv;
2527 		break;
2528 	case EVFILT_WRITE:
2529 		kn->kn_fop = &sowrite_filtops;
2530 		ssb = &so->so_snd;
2531 		break;
2532 	case EVFILT_EXCEPT:
2533 		kn->kn_fop = &soexcept_filtops;
2534 		ssb = &so->so_rcv;
2535 		break;
2536 	default:
2537 		return (EOPNOTSUPP);
2538 	}
2539 
2540 	knote_insert(&ssb->ssb_kq.ki_note, kn);
2541 	atomic_set_int(&ssb->ssb_flags, SSB_KNOTE);
2542 	return (0);
2543 }
2544 
2545 static void
2546 filt_sordetach(struct knote *kn)
2547 {
2548 	struct socket *so = (struct socket *)kn->kn_fp->f_data;
2549 
2550 	knote_remove(&so->so_rcv.ssb_kq.ki_note, kn);
2551 	if (SLIST_EMPTY(&so->so_rcv.ssb_kq.ki_note))
2552 		atomic_clear_int(&so->so_rcv.ssb_flags, SSB_KNOTE);
2553 }
2554 
2555 /*ARGSUSED*/
2556 static int
2557 filt_soread(struct knote *kn, long hint)
2558 {
2559 	struct socket *so = (struct socket *)kn->kn_fp->f_data;
2560 
2561 	if (kn->kn_sfflags & NOTE_OOB) {
2562 		if ((so->so_oobmark || (so->so_state & SS_RCVATMARK))) {
2563 			kn->kn_fflags |= NOTE_OOB;
2564 			return (1);
2565 		}
2566 		return (0);
2567 	}
2568 	kn->kn_data = so->so_rcv.ssb_cc;
2569 
2570 	if (so->so_state & SS_CANTRCVMORE) {
2571 		/*
2572 		 * Only set NODATA if all data has been exhausted.
2573 		 */
2574 		if (kn->kn_data == 0)
2575 			kn->kn_flags |= EV_NODATA;
2576 		kn->kn_flags |= EV_EOF;
2577 		kn->kn_fflags = so->so_error;
2578 		return (1);
2579 	}
2580 	if (so->so_error)	/* temporary udp error */
2581 		return (1);
2582 	if (kn->kn_sfflags & NOTE_LOWAT)
2583 		return (kn->kn_data >= kn->kn_sdata);
2584 	return ((kn->kn_data >= so->so_rcv.ssb_lowat) ||
2585 		!TAILQ_EMPTY(&so->so_comp));
2586 }
2587 
2588 static void
2589 filt_sowdetach(struct knote *kn)
2590 {
2591 	struct socket *so = (struct socket *)kn->kn_fp->f_data;
2592 
2593 	knote_remove(&so->so_snd.ssb_kq.ki_note, kn);
2594 	if (SLIST_EMPTY(&so->so_snd.ssb_kq.ki_note))
2595 		atomic_clear_int(&so->so_snd.ssb_flags, SSB_KNOTE);
2596 }
2597 
2598 /*ARGSUSED*/
2599 static int
2600 filt_sowrite(struct knote *kn, long hint)
2601 {
2602 	struct socket *so = (struct socket *)kn->kn_fp->f_data;
2603 
2604 	kn->kn_data = ssb_space(&so->so_snd);
2605 	if (so->so_state & SS_CANTSENDMORE) {
2606 		kn->kn_flags |= (EV_EOF | EV_NODATA);
2607 		kn->kn_fflags = so->so_error;
2608 		return (1);
2609 	}
2610 	if (so->so_error)	/* temporary udp error */
2611 		return (1);
2612 	if (((so->so_state & SS_ISCONNECTED) == 0) &&
2613 	    (so->so_proto->pr_flags & PR_CONNREQUIRED))
2614 		return (0);
2615 	if (kn->kn_sfflags & NOTE_LOWAT)
2616 		return (kn->kn_data >= kn->kn_sdata);
2617 	return (kn->kn_data >= so->so_snd.ssb_lowat);
2618 }
2619 
2620 /*ARGSUSED*/
2621 static int
2622 filt_solisten(struct knote *kn, long hint)
2623 {
2624 	struct socket *so = (struct socket *)kn->kn_fp->f_data;
2625 
2626 	kn->kn_data = so->so_qlen;
2627 	return (! TAILQ_EMPTY(&so->so_comp));
2628 }
2629