xref: /dflybsd-src/sys/kern/uipc_socket.c (revision 79eafdd799bd34e8b1ec1dc221be9389c7f2b162)
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 #include "opt_sctp.h"
68 
69 #include <sys/param.h>
70 #include <sys/systm.h>
71 #include <sys/fcntl.h>
72 #include <sys/malloc.h>
73 #include <sys/mbuf.h>
74 #include <sys/domain.h>
75 #include <sys/file.h>			/* for struct knote */
76 #include <sys/kernel.h>
77 #include <sys/event.h>
78 #include <sys/proc.h>
79 #include <sys/protosw.h>
80 #include <sys/socket.h>
81 #include <sys/socketvar.h>
82 #include <sys/socketops.h>
83 #include <sys/resourcevar.h>
84 #include <sys/signalvar.h>
85 #include <sys/sysctl.h>
86 #include <sys/uio.h>
87 #include <sys/jail.h>
88 #include <vm/vm_zone.h>
89 #include <vm/pmap.h>
90 #include <net/netmsg2.h>
91 #include <net/netisr2.h>
92 
93 #include <sys/thread2.h>
94 #include <sys/socketvar2.h>
95 #include <sys/spinlock2.h>
96 
97 #include <machine/limits.h>
98 
99 #ifdef INET
100 extern int tcp_sosend_agglim;
101 extern int tcp_sosend_async;
102 extern int tcp_sosend_jcluster;
103 extern int udp_sosend_async;
104 extern int udp_sosend_prepend;
105 
106 static int	 do_setopt_accept_filter(struct socket *so, struct sockopt *sopt);
107 #endif /* INET */
108 
109 static void 	filt_sordetach(struct knote *kn);
110 static int 	filt_soread(struct knote *kn, long hint);
111 static void 	filt_sowdetach(struct knote *kn);
112 static int	filt_sowrite(struct knote *kn, long hint);
113 static int	filt_solisten(struct knote *kn, long hint);
114 
115 static void	sodiscard(struct socket *so);
116 static int	soclose_sync(struct socket *so, int fflag);
117 static void	soclose_fast(struct socket *so);
118 
119 static struct filterops solisten_filtops =
120 	{ FILTEROP_ISFD|FILTEROP_MPSAFE, NULL, filt_sordetach, filt_solisten };
121 static struct filterops soread_filtops =
122 	{ FILTEROP_ISFD|FILTEROP_MPSAFE, NULL, filt_sordetach, filt_soread };
123 static struct filterops sowrite_filtops =
124 	{ FILTEROP_ISFD|FILTEROP_MPSAFE, NULL, filt_sowdetach, filt_sowrite };
125 static struct filterops soexcept_filtops =
126 	{ FILTEROP_ISFD|FILTEROP_MPSAFE, NULL, filt_sordetach, filt_soread };
127 
128 MALLOC_DEFINE(M_SOCKET, "socket", "socket struct");
129 MALLOC_DEFINE(M_SONAME, "soname", "socket name");
130 MALLOC_DEFINE(M_PCB, "pcb", "protocol control block");
131 
132 
133 static int somaxconn = SOMAXCONN;
134 SYSCTL_INT(_kern_ipc, KIPC_SOMAXCONN, somaxconn, CTLFLAG_RW,
135     &somaxconn, 0, "Maximum pending socket connection queue size");
136 
137 static int use_soclose_fast = 1;
138 SYSCTL_INT(_kern_ipc, OID_AUTO, soclose_fast, CTLFLAG_RW,
139     &use_soclose_fast, 0, "Fast socket close");
140 
141 int use_soaccept_pred_fast = 1;
142 SYSCTL_INT(_kern_ipc, OID_AUTO, soaccept_pred_fast, CTLFLAG_RW,
143     &use_soaccept_pred_fast, 0, "Fast socket accept predication");
144 
145 int use_sendfile_async = 1;
146 SYSCTL_INT(_kern_ipc, OID_AUTO, sendfile_async, CTLFLAG_RW,
147     &use_sendfile_async, 0, "sendfile uses asynchronized pru_send");
148 
149 int use_soconnect_async = 1;
150 SYSCTL_INT(_kern_ipc, OID_AUTO, soconnect_async, CTLFLAG_RW,
151     &use_soconnect_async, 0, "soconnect uses asynchronized pru_connect");
152 
153 /*
154  * Socket operation routines.
155  * These routines are called by the routines in
156  * sys_socket.c or from a system process, and
157  * implement the semantics of socket operations by
158  * switching out to the protocol specific routines.
159  */
160 
161 /*
162  * Get a socket structure, and initialize it.
163  * Note that it would probably be better to allocate socket
164  * and PCB at the same time, but I'm not convinced that all
165  * the protocols can be easily modified to do this.
166  */
167 struct socket *
168 soalloc(int waitok, struct protosw *pr)
169 {
170 	struct socket *so;
171 	unsigned waitmask;
172 
173 	waitmask = waitok ? M_WAITOK : M_NOWAIT;
174 	so = kmalloc(sizeof(struct socket), M_SOCKET, M_ZERO|waitmask);
175 	if (so) {
176 		/* XXX race condition for reentrant kernel */
177 		so->so_proto = pr;
178 		TAILQ_INIT(&so->so_aiojobq);
179 		TAILQ_INIT(&so->so_rcv.ssb_kq.ki_mlist);
180 		TAILQ_INIT(&so->so_snd.ssb_kq.ki_mlist);
181 		lwkt_token_init(&so->so_rcv.ssb_token, "rcvtok");
182 		lwkt_token_init(&so->so_snd.ssb_token, "sndtok");
183 		spin_init(&so->so_rcvd_spin, "soalloc");
184 		netmsg_init(&so->so_rcvd_msg.base, so, &netisr_adone_rport,
185 		    MSGF_DROPABLE | MSGF_PRIORITY,
186 		    so->so_proto->pr_usrreqs->pru_rcvd);
187 		so->so_rcvd_msg.nm_pru_flags |= PRUR_ASYNC;
188 		so->so_state = SS_NOFDREF;
189 		so->so_refs = 1;
190 	}
191 	return so;
192 }
193 
194 int
195 socreate(int dom, struct socket **aso, int type,
196 	int proto, struct thread *td)
197 {
198 	struct proc *p = td->td_proc;
199 	struct protosw *prp;
200 	struct socket *so;
201 	struct pru_attach_info ai;
202 	int error;
203 
204 	if (proto)
205 		prp = pffindproto(dom, proto, type);
206 	else
207 		prp = pffindtype(dom, type);
208 
209 	if (prp == NULL || prp->pr_usrreqs->pru_attach == 0)
210 		return (EPROTONOSUPPORT);
211 
212 	if (p->p_ucred->cr_prison && jail_socket_unixiproute_only &&
213 	    prp->pr_domain->dom_family != PF_LOCAL &&
214 	    prp->pr_domain->dom_family != PF_INET &&
215 	    prp->pr_domain->dom_family != PF_INET6 &&
216 	    prp->pr_domain->dom_family != PF_ROUTE) {
217 		return (EPROTONOSUPPORT);
218 	}
219 
220 	if (prp->pr_type != type)
221 		return (EPROTOTYPE);
222 	so = soalloc(p != NULL, prp);
223 	if (so == NULL)
224 		return (ENOBUFS);
225 
226 	/*
227 	 * Callers of socreate() presumably will connect up a descriptor
228 	 * and call soclose() if they cannot.  This represents our so_refs
229 	 * (which should be 1) from soalloc().
230 	 */
231 	soclrstate(so, SS_NOFDREF);
232 
233 	/*
234 	 * Set a default port for protocol processing.  No action will occur
235 	 * on the socket on this port until an inpcb is attached to it and
236 	 * is able to match incoming packets, or until the socket becomes
237 	 * available to userland.
238 	 *
239 	 * We normally default the socket to the protocol thread on cpu 0,
240 	 * if protocol does not provide its own method to initialize the
241 	 * default port.
242 	 *
243 	 * If PR_SYNC_PORT is set (unix domain sockets) there is no protocol
244 	 * thread and all pr_*()/pru_*() calls are executed synchronously.
245 	 */
246 	if (prp->pr_flags & PR_SYNC_PORT)
247 		so->so_port = &netisr_sync_port;
248 	else if (prp->pr_initport != NULL)
249 		so->so_port = prp->pr_initport();
250 	else
251 		so->so_port = netisr_cpuport(0);
252 
253 	TAILQ_INIT(&so->so_incomp);
254 	TAILQ_INIT(&so->so_comp);
255 	so->so_type = type;
256 	so->so_cred = crhold(p->p_ucred);
257 	ai.sb_rlimit = &p->p_rlimit[RLIMIT_SBSIZE];
258 	ai.p_ucred = p->p_ucred;
259 	ai.fd_rdir = p->p_fd->fd_rdir;
260 
261 	/*
262 	 * Auto-sizing of socket buffers is managed by the protocols and
263 	 * the appropriate flags must be set in the pru_attach function.
264 	 */
265 	error = so_pru_attach(so, proto, &ai);
266 	if (error) {
267 		sosetstate(so, SS_NOFDREF);
268 		sofree(so);	/* from soalloc */
269 		return error;
270 	}
271 
272 	/*
273 	 * NOTE: Returns referenced socket.
274 	 */
275 	*aso = so;
276 	return (0);
277 }
278 
279 int
280 sobind(struct socket *so, struct sockaddr *nam, struct thread *td)
281 {
282 	int error;
283 
284 	error = so_pru_bind(so, nam, td);
285 	return (error);
286 }
287 
288 static void
289 sodealloc(struct socket *so)
290 {
291 	if (so->so_rcv.ssb_hiwat)
292 		(void)chgsbsize(so->so_cred->cr_uidinfo,
293 		    &so->so_rcv.ssb_hiwat, 0, RLIM_INFINITY);
294 	if (so->so_snd.ssb_hiwat)
295 		(void)chgsbsize(so->so_cred->cr_uidinfo,
296 		    &so->so_snd.ssb_hiwat, 0, RLIM_INFINITY);
297 #ifdef INET
298 	/* remove accept filter if present */
299 	if (so->so_accf != NULL)
300 		do_setopt_accept_filter(so, NULL);
301 #endif /* INET */
302 	crfree(so->so_cred);
303 	if (so->so_faddr != NULL)
304 		kfree(so->so_faddr, M_SONAME);
305 	kfree(so, M_SOCKET);
306 }
307 
308 int
309 solisten(struct socket *so, int backlog, struct thread *td)
310 {
311 	int error;
312 #ifdef SCTP
313 	short oldopt, oldqlimit;
314 #endif /* SCTP */
315 
316 	if (so->so_state & (SS_ISCONNECTED | SS_ISCONNECTING))
317 		return (EINVAL);
318 
319 #ifdef SCTP
320 	oldopt = so->so_options;
321 	oldqlimit = so->so_qlimit;
322 #endif /* SCTP */
323 
324 	lwkt_gettoken(&so->so_rcv.ssb_token);
325 	if (TAILQ_EMPTY(&so->so_comp))
326 		so->so_options |= SO_ACCEPTCONN;
327 	lwkt_reltoken(&so->so_rcv.ssb_token);
328 	if (backlog < 0 || backlog > somaxconn)
329 		backlog = somaxconn;
330 	so->so_qlimit = backlog;
331 	/* SCTP needs to look at tweak both the inbound backlog parameter AND
332 	 * the so_options (UDP model both connect's and gets inbound
333 	 * connections .. implicitly).
334 	 */
335 	error = so_pru_listen(so, td);
336 	if (error) {
337 #ifdef SCTP
338 		/* Restore the params */
339 		so->so_options = oldopt;
340 		so->so_qlimit = oldqlimit;
341 #endif /* SCTP */
342 		return (error);
343 	}
344 	return (0);
345 }
346 
347 /*
348  * Destroy a disconnected socket.  This routine is a NOP if entities
349  * still have a reference on the socket:
350  *
351  *	so_pcb -	The protocol stack still has a reference
352  *	SS_NOFDREF -	There is no longer a file pointer reference
353  */
354 void
355 sofree(struct socket *so)
356 {
357 	struct socket *head;
358 
359 	/*
360 	 * This is a bit hackish at the moment.  We need to interlock
361 	 * any accept queue we are on before we potentially lose the
362 	 * last reference to avoid races against a re-reference from
363 	 * someone operating on the queue.
364 	 */
365 	while ((head = so->so_head) != NULL) {
366 		lwkt_getpooltoken(head);
367 		if (so->so_head == head)
368 			break;
369 		lwkt_relpooltoken(head);
370 	}
371 
372 	/*
373 	 * Arbitrage the last free.
374 	 */
375 	KKASSERT(so->so_refs > 0);
376 	if (atomic_fetchadd_int(&so->so_refs, -1) != 1) {
377 		if (head)
378 			lwkt_relpooltoken(head);
379 		return;
380 	}
381 
382 	KKASSERT(so->so_pcb == NULL && (so->so_state & SS_NOFDREF));
383 	KKASSERT((so->so_state & SS_ASSERTINPROG) == 0);
384 
385 	/*
386 	 * We're done, remove ourselves from the accept queue we are
387 	 * on, if we are on one.
388 	 */
389 	if (head != NULL) {
390 		if (so->so_state & SS_INCOMP) {
391 			TAILQ_REMOVE(&head->so_incomp, so, so_list);
392 			head->so_incqlen--;
393 		} else if (so->so_state & SS_COMP) {
394 			/*
395 			 * We must not decommission a socket that's
396 			 * on the accept(2) queue.  If we do, then
397 			 * accept(2) may hang after select(2) indicated
398 			 * that the listening socket was ready.
399 			 */
400 			lwkt_relpooltoken(head);
401 			return;
402 		} else {
403 			panic("sofree: not queued");
404 		}
405 		soclrstate(so, SS_INCOMP);
406 		so->so_head = NULL;
407 		lwkt_relpooltoken(head);
408 	}
409 	ssb_release(&so->so_snd, so);
410 	sorflush(so);
411 	sodealloc(so);
412 }
413 
414 /*
415  * Close a socket on last file table reference removal.
416  * Initiate disconnect if connected.
417  * Free socket when disconnect complete.
418  */
419 int
420 soclose(struct socket *so, int fflag)
421 {
422 	int error;
423 
424 	funsetown(&so->so_sigio);
425 	if (!use_soclose_fast ||
426 	    (so->so_proto->pr_flags & PR_SYNC_PORT) ||
427 	    ((so->so_state & SS_ISCONNECTED) &&
428 	     (so->so_options & SO_LINGER))) {
429 		error = soclose_sync(so, fflag);
430 	} else {
431 		soclose_fast(so);
432 		error = 0;
433 	}
434 	return error;
435 }
436 
437 static void
438 sodiscard(struct socket *so)
439 {
440 	lwkt_getpooltoken(so);
441 	if (so->so_options & SO_ACCEPTCONN) {
442 		struct socket *sp;
443 
444 		while ((sp = TAILQ_FIRST(&so->so_incomp)) != NULL) {
445 			TAILQ_REMOVE(&so->so_incomp, sp, so_list);
446 			soclrstate(sp, SS_INCOMP);
447 			sp->so_head = NULL;
448 			so->so_incqlen--;
449 			soabort_async(sp);
450 		}
451 		while ((sp = TAILQ_FIRST(&so->so_comp)) != NULL) {
452 			TAILQ_REMOVE(&so->so_comp, sp, so_list);
453 			soclrstate(sp, SS_COMP);
454 			sp->so_head = NULL;
455 			so->so_qlen--;
456 			soabort_async(sp);
457 		}
458 	}
459 	lwkt_relpooltoken(so);
460 
461 	if (so->so_state & SS_NOFDREF)
462 		panic("soclose: NOFDREF");
463 	sosetstate(so, SS_NOFDREF);	/* take ref */
464 }
465 
466 void
467 soinherit(struct socket *so, struct socket *so_inh)
468 {
469 	TAILQ_HEAD(, socket) comp, incomp;
470 	struct socket *sp;
471 	int qlen, incqlen;
472 
473 	KASSERT(so->so_options & SO_ACCEPTCONN,
474 	    ("so does not accept connection"));
475 	KASSERT(so_inh->so_options & SO_ACCEPTCONN,
476 	    ("so_inh does not accept connection"));
477 
478 	TAILQ_INIT(&comp);
479 	TAILQ_INIT(&incomp);
480 
481 	lwkt_getpooltoken(so);
482 	lwkt_getpooltoken(so_inh);
483 
484 	/*
485 	 * Save completed queue and incompleted queue
486 	 */
487 	TAILQ_CONCAT(&comp, &so->so_comp, so_list);
488 	qlen = so->so_qlen;
489 	so->so_qlen = 0;
490 
491 	TAILQ_CONCAT(&incomp, &so->so_incomp, so_list);
492 	incqlen = so->so_incqlen;
493 	so->so_incqlen = 0;
494 
495 	/*
496 	 * Append the saved completed queue and incompleted
497 	 * queue to the socket inherits them.
498 	 *
499 	 * XXX
500 	 * This may temporarily break the inheriting socket's
501 	 * so_qlimit.
502 	 */
503 	TAILQ_FOREACH(sp, &comp, so_list) {
504 		sp->so_head = so_inh;
505 		crfree(sp->so_cred);
506 		sp->so_cred = crhold(so_inh->so_cred);
507 	}
508 
509 	TAILQ_FOREACH(sp, &incomp, so_list) {
510 		sp->so_head = so_inh;
511 		crfree(sp->so_cred);
512 		sp->so_cred = crhold(so_inh->so_cred);
513 	}
514 
515 	TAILQ_CONCAT(&so_inh->so_comp, &comp, so_list);
516 	so_inh->so_qlen += qlen;
517 
518 	TAILQ_CONCAT(&so_inh->so_incomp, &incomp, so_list);
519 	so_inh->so_incqlen += incqlen;
520 
521 	lwkt_relpooltoken(so_inh);
522 	lwkt_relpooltoken(so);
523 
524 	if (qlen) {
525 		/*
526 		 * "New" connections have arrived
527 		 */
528 		sorwakeup(so_inh);
529 		wakeup(&so_inh->so_timeo);
530 	}
531 }
532 
533 static int
534 soclose_sync(struct socket *so, int fflag)
535 {
536 	int error = 0;
537 
538 	if (so->so_pcb == NULL)
539 		goto discard;
540 	if (so->so_state & SS_ISCONNECTED) {
541 		if ((so->so_state & SS_ISDISCONNECTING) == 0) {
542 			error = sodisconnect(so);
543 			if (error)
544 				goto drop;
545 		}
546 		if (so->so_options & SO_LINGER) {
547 			if ((so->so_state & SS_ISDISCONNECTING) &&
548 			    (fflag & FNONBLOCK))
549 				goto drop;
550 			while (so->so_state & SS_ISCONNECTED) {
551 				error = tsleep(&so->so_timeo, PCATCH,
552 					       "soclos", so->so_linger * hz);
553 				if (error)
554 					break;
555 			}
556 		}
557 	}
558 drop:
559 	if (so->so_pcb) {
560 		int error2;
561 
562 		error2 = so_pru_detach(so);
563 		if (error == 0)
564 			error = error2;
565 	}
566 discard:
567 	sodiscard(so);
568 	so_pru_sync(so);	/* unpend async sending */
569 	sofree(so);		/* dispose of ref */
570 
571 	return (error);
572 }
573 
574 static void
575 soclose_sofree_async_handler(netmsg_t msg)
576 {
577 	sofree(msg->base.nm_so);
578 }
579 
580 static void
581 soclose_sofree_async(struct socket *so)
582 {
583 	struct netmsg_base *base = &so->so_clomsg;
584 
585 	netmsg_init(base, so, &netisr_apanic_rport, 0,
586 	    soclose_sofree_async_handler);
587 	lwkt_sendmsg(so->so_port, &base->lmsg);
588 }
589 
590 static void
591 soclose_disconn_async_handler(netmsg_t msg)
592 {
593 	struct socket *so = msg->base.nm_so;
594 
595 	if ((so->so_state & SS_ISCONNECTED) &&
596 	    (so->so_state & SS_ISDISCONNECTING) == 0)
597 		so_pru_disconnect_direct(so);
598 
599 	if (so->so_pcb)
600 		so_pru_detach_direct(so);
601 
602 	sodiscard(so);
603 	sofree(so);
604 }
605 
606 static void
607 soclose_disconn_async(struct socket *so)
608 {
609 	struct netmsg_base *base = &so->so_clomsg;
610 
611 	netmsg_init(base, so, &netisr_apanic_rport, 0,
612 	    soclose_disconn_async_handler);
613 	lwkt_sendmsg(so->so_port, &base->lmsg);
614 }
615 
616 static void
617 soclose_detach_async_handler(netmsg_t msg)
618 {
619 	struct socket *so = msg->base.nm_so;
620 
621 	if (so->so_pcb)
622 		so_pru_detach_direct(so);
623 
624 	sodiscard(so);
625 	sofree(so);
626 }
627 
628 static void
629 soclose_detach_async(struct socket *so)
630 {
631 	struct netmsg_base *base = &so->so_clomsg;
632 
633 	netmsg_init(base, so, &netisr_apanic_rport, 0,
634 	    soclose_detach_async_handler);
635 	lwkt_sendmsg(so->so_port, &base->lmsg);
636 }
637 
638 static void
639 soclose_fast(struct socket *so)
640 {
641 	if (so->so_pcb == NULL)
642 		goto discard;
643 
644 	if ((so->so_state & SS_ISCONNECTED) &&
645 	    (so->so_state & SS_ISDISCONNECTING) == 0) {
646 		soclose_disconn_async(so);
647 		return;
648 	}
649 
650 	if (so->so_pcb) {
651 		soclose_detach_async(so);
652 		return;
653 	}
654 
655 discard:
656 	sodiscard(so);
657 	soclose_sofree_async(so);
658 }
659 
660 /*
661  * Abort and destroy a socket.  Only one abort can be in progress
662  * at any given moment.
663  */
664 void
665 soabort(struct socket *so)
666 {
667 	soreference(so);
668 	so_pru_abort(so);
669 }
670 
671 void
672 soabort_async(struct socket *so)
673 {
674 	soreference(so);
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, MB_WAIT, 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, MB_WAIT,
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, MB_WAIT, MT_DATA,
1185 					   top == NULL ? M_PKTHDR : 0, &mlen);
1186 			} else {
1187 				m = m_getl((int)resid, MB_WAIT, 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(MB_WAIT, 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 #ifdef SCTP
1433 	if (pr->pr_flags & PR_ADDR_OPT) {
1434 		/*
1435 		 * For SCTP we may be getting a
1436 		 * whole message OR a partial delivery.
1437 		 */
1438 		if (m && m->m_type == MT_SONAME) {
1439 			orig_resid = 0;
1440 			if (psa)
1441 				*psa = dup_sockaddr(mtod(m, struct sockaddr *));
1442 			if (flags & MSG_PEEK)
1443 				m = m->m_next;
1444 			else
1445 				m = sbunlinkmbuf(&so->so_rcv.sb, m, &free_chain);
1446 		}
1447 	}
1448 #endif /* SCTP */
1449 	while (m && m->m_type == MT_CONTROL && error == 0) {
1450 		if (flags & MSG_PEEK) {
1451 			if (controlp)
1452 				*controlp = m_copy(m, 0, m->m_len);
1453 			m = m->m_next;	/* XXX race */
1454 		} else {
1455 			if (controlp) {
1456 				n = sbunlinkmbuf(&so->so_rcv.sb, m, NULL);
1457 				if (pr->pr_domain->dom_externalize &&
1458 				    mtod(m, struct cmsghdr *)->cmsg_type ==
1459 				    SCM_RIGHTS)
1460 				   error = (*pr->pr_domain->dom_externalize)(m);
1461 				*controlp = m;
1462 				m = n;
1463 			} else {
1464 				m = sbunlinkmbuf(&so->so_rcv.sb, m, &free_chain);
1465 			}
1466 		}
1467 		if (controlp && *controlp) {
1468 			orig_resid = 0;
1469 			controlp = &(*controlp)->m_next;
1470 		}
1471 	}
1472 
1473 	/*
1474 	 * flag OOB data.
1475 	 */
1476 	if (m) {
1477 		type = m->m_type;
1478 		if (type == MT_OOBDATA)
1479 			flags |= MSG_OOB;
1480 	}
1481 
1482 	/*
1483 	 * Copy to the UIO or mbuf return chain (*mp).
1484 	 */
1485 	moff = 0;
1486 	offset = 0;
1487 	while (m && resid > 0 && error == 0) {
1488 		if (m->m_type == MT_OOBDATA) {
1489 			if (type != MT_OOBDATA)
1490 				break;
1491 		} else if (type == MT_OOBDATA)
1492 			break;
1493 		else
1494 		    KASSERT(m->m_type == MT_DATA || m->m_type == MT_HEADER,
1495 			("receive 3"));
1496 		soclrstate(so, SS_RCVATMARK);
1497 		len = (resid > INT_MAX) ? INT_MAX : resid;
1498 		if (so->so_oobmark && len > so->so_oobmark - offset)
1499 			len = so->so_oobmark - offset;
1500 		if (len > m->m_len - moff)
1501 			len = m->m_len - moff;
1502 
1503 		/*
1504 		 * Copy out to the UIO or pass the mbufs back to the SIO.
1505 		 * The SIO is dealt with when we eat the mbuf, but deal
1506 		 * with the resid here either way.
1507 		 */
1508 		if (uio) {
1509 			uio->uio_resid = resid;
1510 			error = uiomove(mtod(m, caddr_t) + moff, len, uio);
1511 			resid = uio->uio_resid;
1512 			if (error)
1513 				goto release;
1514 		} else {
1515 			resid -= (size_t)len;
1516 		}
1517 
1518 		/*
1519 		 * Eat the entire mbuf or just a piece of it
1520 		 */
1521 		if (len == m->m_len - moff) {
1522 			if (m->m_flags & M_EOR)
1523 				flags |= MSG_EOR;
1524 #ifdef SCTP
1525 			if (m->m_flags & M_NOTIFICATION)
1526 				flags |= MSG_NOTIFICATION;
1527 #endif /* SCTP */
1528 			if (flags & MSG_PEEK) {
1529 				m = m->m_next;
1530 				moff = 0;
1531 			} else {
1532 				if (sio) {
1533 					n = sbunlinkmbuf(&so->so_rcv.sb, m, NULL);
1534 					sbappend(sio, m);
1535 					m = n;
1536 				} else {
1537 					m = sbunlinkmbuf(&so->so_rcv.sb, m, &free_chain);
1538 				}
1539 			}
1540 		} else {
1541 			if (flags & MSG_PEEK) {
1542 				moff += len;
1543 			} else {
1544 				if (sio) {
1545 					n = m_copym(m, 0, len, MB_WAIT);
1546 					if (n)
1547 						sbappend(sio, n);
1548 				}
1549 				m->m_data += len;
1550 				m->m_len -= len;
1551 				so->so_rcv.ssb_cc -= len;
1552 			}
1553 		}
1554 		if (so->so_oobmark) {
1555 			if ((flags & MSG_PEEK) == 0) {
1556 				so->so_oobmark -= len;
1557 				if (so->so_oobmark == 0) {
1558 					sosetstate(so, SS_RCVATMARK);
1559 					break;
1560 				}
1561 			} else {
1562 				offset += len;
1563 				if (offset == so->so_oobmark)
1564 					break;
1565 			}
1566 		}
1567 		if (flags & MSG_EOR)
1568 			break;
1569 		/*
1570 		 * If the MSG_WAITALL flag is set (for non-atomic socket),
1571 		 * we must not quit until resid == 0 or an error
1572 		 * termination.  If a signal/timeout occurs, return
1573 		 * with a short count but without error.
1574 		 * Keep signalsockbuf locked against other readers.
1575 		 */
1576 		while ((flags & MSG_WAITALL) && m == NULL &&
1577 		       resid > 0 && !sosendallatonce(so) &&
1578 		       so->so_rcv.ssb_mb == NULL) {
1579 			if (so->so_error || so->so_state & SS_CANTRCVMORE)
1580 				break;
1581 			/*
1582 			 * The window might have closed to zero, make
1583 			 * sure we send an ack now that we've drained
1584 			 * the buffer or we might end up blocking until
1585 			 * the idle takes over (5 seconds).
1586 			 */
1587 			if (pr->pr_flags & PR_WANTRCVD && so->so_pcb)
1588 				so_pru_rcvd(so, flags);
1589 			error = ssb_wait(&so->so_rcv);
1590 			if (error) {
1591 				ssb_unlock(&so->so_rcv);
1592 				error = 0;
1593 				goto done;
1594 			}
1595 			m = so->so_rcv.ssb_mb;
1596 		}
1597 	}
1598 
1599 	/*
1600 	 * If an atomic read was requested but unread data still remains
1601 	 * in the record, set MSG_TRUNC.
1602 	 */
1603 	if (m && pr->pr_flags & PR_ATOMIC)
1604 		flags |= MSG_TRUNC;
1605 
1606 	/*
1607 	 * Cleanup.  If an atomic read was requested drop any unread data.
1608 	 */
1609 	if ((flags & MSG_PEEK) == 0) {
1610 		if (m && (pr->pr_flags & PR_ATOMIC))
1611 			sbdroprecord(&so->so_rcv.sb);
1612 		if ((pr->pr_flags & PR_WANTRCVD) && so->so_pcb)
1613 			so_pru_rcvd(so, flags);
1614 	}
1615 
1616 	if (orig_resid == resid && orig_resid &&
1617 	    (flags & MSG_EOR) == 0 && (so->so_state & SS_CANTRCVMORE) == 0) {
1618 		ssb_unlock(&so->so_rcv);
1619 		goto restart;
1620 	}
1621 
1622 	if (flagsp)
1623 		*flagsp |= flags;
1624 release:
1625 	ssb_unlock(&so->so_rcv);
1626 done:
1627 	lwkt_reltoken(&so->so_rcv.ssb_token);
1628 	if (free_chain)
1629 		m_freem(free_chain);
1630 	return (error);
1631 }
1632 
1633 int
1634 sorecvtcp(struct socket *so, struct sockaddr **psa, struct uio *uio,
1635 	  struct sockbuf *sio, struct mbuf **controlp, int *flagsp)
1636 {
1637 	struct mbuf *m, *n;
1638 	struct mbuf *free_chain = NULL;
1639 	int flags, len, error, offset;
1640 	struct protosw *pr = so->so_proto;
1641 	int moff;
1642 	int didoob;
1643 	size_t resid, orig_resid, restmp;
1644 
1645 	if (uio)
1646 		resid = uio->uio_resid;
1647 	else
1648 		resid = (size_t)(sio->sb_climit - sio->sb_cc);
1649 	orig_resid = resid;
1650 
1651 	if (psa)
1652 		*psa = NULL;
1653 	if (controlp)
1654 		*controlp = NULL;
1655 	if (flagsp)
1656 		flags = *flagsp &~ MSG_EOR;
1657 	else
1658 		flags = 0;
1659 	if (flags & MSG_OOB) {
1660 		m = m_get(MB_WAIT, MT_DATA);
1661 		if (m == NULL)
1662 			return (ENOBUFS);
1663 		error = so_pru_rcvoob(so, m, flags & MSG_PEEK);
1664 		if (error)
1665 			goto bad;
1666 		if (sio) {
1667 			do {
1668 				sbappend(sio, m);
1669 				KKASSERT(resid >= (size_t)m->m_len);
1670 				resid -= (size_t)m->m_len;
1671 			} while (resid > 0 && m);
1672 		} else {
1673 			do {
1674 				uio->uio_resid = resid;
1675 				error = uiomove(mtod(m, caddr_t),
1676 						(int)szmin(resid, m->m_len),
1677 						uio);
1678 				resid = uio->uio_resid;
1679 				m = m_free(m);
1680 			} while (uio->uio_resid && error == 0 && m);
1681 		}
1682 bad:
1683 		if (m)
1684 			m_freem(m);
1685 		return (error);
1686 	}
1687 
1688 	/*
1689 	 * The token interlocks against the protocol thread while
1690 	 * ssb_lock is a blocking lock against other userland entities.
1691 	 *
1692 	 * Lock a limited number of mbufs (not all, so sbcompress() still
1693 	 * works well).  The token is used as an interlock for sbwait() so
1694 	 * release it afterwords.
1695 	 */
1696 restart:
1697 	error = ssb_lock(&so->so_rcv, SBLOCKWAIT(flags));
1698 	if (error)
1699 		goto done;
1700 
1701 	lwkt_gettoken(&so->so_rcv.ssb_token);
1702 	m = so->so_rcv.ssb_mb;
1703 
1704 	/*
1705 	 * If we have less data than requested, block awaiting more
1706 	 * (subject to any timeout) if:
1707 	 *   1. the current count is less than the low water mark, or
1708 	 *   2. MSG_WAITALL is set, and it is possible to do the entire
1709 	 *	receive operation at once if we block (resid <= hiwat).
1710 	 *   3. MSG_DONTWAIT is not set
1711 	 * If MSG_WAITALL is set but resid is larger than the receive buffer,
1712 	 * we have to do the receive in sections, and thus risk returning
1713 	 * a short count if a timeout or signal occurs after we start.
1714 	 */
1715 	if (m == NULL || (((flags & MSG_DONTWAIT) == 0 &&
1716 	    (size_t)so->so_rcv.ssb_cc < resid) &&
1717 	    (so->so_rcv.ssb_cc < so->so_rcv.ssb_lowat ||
1718 	   ((flags & MSG_WAITALL) && resid <= (size_t)so->so_rcv.ssb_hiwat)))) {
1719 		KASSERT(m != NULL || !so->so_rcv.ssb_cc, ("receive 1"));
1720 		if (so->so_error) {
1721 			if (m)
1722 				goto dontblock;
1723 			lwkt_reltoken(&so->so_rcv.ssb_token);
1724 			error = so->so_error;
1725 			if ((flags & MSG_PEEK) == 0)
1726 				so->so_error = 0;
1727 			goto release;
1728 		}
1729 		if (so->so_state & SS_CANTRCVMORE) {
1730 			if (m)
1731 				goto dontblock;
1732 			lwkt_reltoken(&so->so_rcv.ssb_token);
1733 			goto release;
1734 		}
1735 		if ((so->so_state & (SS_ISCONNECTED|SS_ISCONNECTING)) == 0 &&
1736 		    (pr->pr_flags & PR_CONNREQUIRED)) {
1737 			lwkt_reltoken(&so->so_rcv.ssb_token);
1738 			error = ENOTCONN;
1739 			goto release;
1740 		}
1741 		if (resid == 0) {
1742 			lwkt_reltoken(&so->so_rcv.ssb_token);
1743 			goto release;
1744 		}
1745 		if (flags & (MSG_FNONBLOCKING|MSG_DONTWAIT)) {
1746 			lwkt_reltoken(&so->so_rcv.ssb_token);
1747 			error = EWOULDBLOCK;
1748 			goto release;
1749 		}
1750 		ssb_unlock(&so->so_rcv);
1751 		error = ssb_wait(&so->so_rcv);
1752 		lwkt_reltoken(&so->so_rcv.ssb_token);
1753 		if (error)
1754 			goto done;
1755 		goto restart;
1756 	}
1757 
1758 	/*
1759 	 * Token still held
1760 	 */
1761 dontblock:
1762 	n = m;
1763 	restmp = 0;
1764 	while (n && restmp < resid) {
1765 		n->m_flags |= M_SOLOCKED;
1766 		restmp += n->m_len;
1767 		if (n->m_next == NULL)
1768 			n = n->m_nextpkt;
1769 		else
1770 			n = n->m_next;
1771 	}
1772 
1773 	/*
1774 	 * Release token for loop
1775 	 */
1776 	lwkt_reltoken(&so->so_rcv.ssb_token);
1777 	if (uio && uio->uio_td && uio->uio_td->td_proc)
1778 		uio->uio_td->td_lwp->lwp_ru.ru_msgrcv++;
1779 
1780 	/*
1781 	 * note: m should be == sb_mb here.  Cache the next record while
1782 	 * cleaning up.  Note that calling m_free*() will break out critical
1783 	 * section.
1784 	 */
1785 	KKASSERT(m == so->so_rcv.ssb_mb);
1786 
1787 	/*
1788 	 * Copy to the UIO or mbuf return chain (*mp).
1789 	 *
1790 	 * NOTE: Token is not held for loop
1791 	 */
1792 	moff = 0;
1793 	offset = 0;
1794 	didoob = 0;
1795 
1796 	while (m && (m->m_flags & M_SOLOCKED) && resid > 0 && error == 0) {
1797 		KASSERT(m->m_type == MT_DATA || m->m_type == MT_HEADER,
1798 		    ("receive 3"));
1799 
1800 		soclrstate(so, SS_RCVATMARK);
1801 		len = (resid > INT_MAX) ? INT_MAX : resid;
1802 		if (so->so_oobmark && len > so->so_oobmark - offset)
1803 			len = so->so_oobmark - offset;
1804 		if (len > m->m_len - moff)
1805 			len = m->m_len - moff;
1806 
1807 		/*
1808 		 * Copy out to the UIO or pass the mbufs back to the SIO.
1809 		 * The SIO is dealt with when we eat the mbuf, but deal
1810 		 * with the resid here either way.
1811 		 */
1812 		if (uio) {
1813 			uio->uio_resid = resid;
1814 			error = uiomove(mtod(m, caddr_t) + moff, len, uio);
1815 			resid = uio->uio_resid;
1816 			if (error)
1817 				goto release;
1818 		} else {
1819 			resid -= (size_t)len;
1820 		}
1821 
1822 		/*
1823 		 * Eat the entire mbuf or just a piece of it
1824 		 */
1825 		offset += len;
1826 		if (len == m->m_len - moff) {
1827 			m = m->m_next;
1828 			moff = 0;
1829 		} else {
1830 			moff += len;
1831 		}
1832 
1833 		/*
1834 		 * Check oobmark
1835 		 */
1836 		if (so->so_oobmark && offset == so->so_oobmark) {
1837 			didoob = 1;
1838 			break;
1839 		}
1840 	}
1841 
1842 	/*
1843 	 * Synchronize sockbuf with data we read.
1844 	 *
1845 	 * NOTE: (m) is junk on entry (it could be left over from the
1846 	 *	 previous loop).
1847 	 */
1848 	if ((flags & MSG_PEEK) == 0) {
1849 		lwkt_gettoken(&so->so_rcv.ssb_token);
1850 		m = so->so_rcv.ssb_mb;
1851 		while (m && offset >= m->m_len) {
1852 			if (so->so_oobmark) {
1853 				so->so_oobmark -= m->m_len;
1854 				if (so->so_oobmark == 0) {
1855 					sosetstate(so, SS_RCVATMARK);
1856 					didoob = 1;
1857 				}
1858 			}
1859 			offset -= m->m_len;
1860 			if (sio) {
1861 				n = sbunlinkmbuf(&so->so_rcv.sb, m, NULL);
1862 				sbappend(sio, m);
1863 				m = n;
1864 			} else {
1865 				m = sbunlinkmbuf(&so->so_rcv.sb,
1866 						 m, &free_chain);
1867 			}
1868 		}
1869 		if (offset) {
1870 			KKASSERT(m);
1871 			if (sio) {
1872 				n = m_copym(m, 0, offset, MB_WAIT);
1873 				if (n)
1874 					sbappend(sio, n);
1875 			}
1876 			m->m_data += offset;
1877 			m->m_len -= offset;
1878 			so->so_rcv.ssb_cc -= offset;
1879 			if (so->so_oobmark) {
1880 				so->so_oobmark -= offset;
1881 				if (so->so_oobmark == 0) {
1882 					sosetstate(so, SS_RCVATMARK);
1883 					didoob = 1;
1884 				}
1885 			}
1886 			offset = 0;
1887 		}
1888 		lwkt_reltoken(&so->so_rcv.ssb_token);
1889 	}
1890 
1891 	/*
1892 	 * If the MSG_WAITALL flag is set (for non-atomic socket),
1893 	 * we must not quit until resid == 0 or an error termination.
1894 	 *
1895 	 * If a signal/timeout occurs, return with a short count but without
1896 	 * error.
1897 	 *
1898 	 * Keep signalsockbuf locked against other readers.
1899 	 *
1900 	 * XXX if MSG_PEEK we currently do quit.
1901 	 */
1902 	if ((flags & MSG_WAITALL) && !(flags & MSG_PEEK) &&
1903 	    didoob == 0 && resid > 0 &&
1904 	    !sosendallatonce(so)) {
1905 		lwkt_gettoken(&so->so_rcv.ssb_token);
1906 		error = 0;
1907 		while ((m = so->so_rcv.ssb_mb) == NULL) {
1908 			if (so->so_error || (so->so_state & SS_CANTRCVMORE)) {
1909 				error = so->so_error;
1910 				break;
1911 			}
1912 			/*
1913 			 * The window might have closed to zero, make
1914 			 * sure we send an ack now that we've drained
1915 			 * the buffer or we might end up blocking until
1916 			 * the idle takes over (5 seconds).
1917 			 */
1918 			if (so->so_pcb)
1919 				so_pru_rcvd_async(so);
1920 			if (so->so_rcv.ssb_mb == NULL)
1921 				error = ssb_wait(&so->so_rcv);
1922 			if (error) {
1923 				lwkt_reltoken(&so->so_rcv.ssb_token);
1924 				ssb_unlock(&so->so_rcv);
1925 				error = 0;
1926 				goto done;
1927 			}
1928 		}
1929 		if (m && error == 0)
1930 			goto dontblock;
1931 		lwkt_reltoken(&so->so_rcv.ssb_token);
1932 	}
1933 
1934 	/*
1935 	 * Token not held here.
1936 	 *
1937 	 * Cleanup.  If an atomic read was requested drop any unread data XXX
1938 	 */
1939 	if ((flags & MSG_PEEK) == 0) {
1940 		if (so->so_pcb)
1941 			so_pru_rcvd_async(so);
1942 	}
1943 
1944 	if (orig_resid == resid && orig_resid &&
1945 	    (so->so_state & SS_CANTRCVMORE) == 0) {
1946 		ssb_unlock(&so->so_rcv);
1947 		goto restart;
1948 	}
1949 
1950 	if (flagsp)
1951 		*flagsp |= flags;
1952 release:
1953 	ssb_unlock(&so->so_rcv);
1954 done:
1955 	if (free_chain)
1956 		m_freem(free_chain);
1957 	return (error);
1958 }
1959 
1960 /*
1961  * Shut a socket down.  Note that we do not get a frontend lock as we
1962  * want to be able to shut the socket down even if another thread is
1963  * blocked in a read(), thus waking it up.
1964  */
1965 int
1966 soshutdown(struct socket *so, int how)
1967 {
1968 	if (!(how == SHUT_RD || how == SHUT_WR || how == SHUT_RDWR))
1969 		return (EINVAL);
1970 
1971 	if (how != SHUT_WR) {
1972 		/*ssb_lock(&so->so_rcv, M_WAITOK);*/
1973 		sorflush(so);
1974 		/*ssb_unlock(&so->so_rcv);*/
1975 	}
1976 	if (how != SHUT_RD)
1977 		return (so_pru_shutdown(so));
1978 	return (0);
1979 }
1980 
1981 void
1982 sorflush(struct socket *so)
1983 {
1984 	struct signalsockbuf *ssb = &so->so_rcv;
1985 	struct protosw *pr = so->so_proto;
1986 	struct signalsockbuf asb;
1987 
1988 	atomic_set_int(&ssb->ssb_flags, SSB_NOINTR);
1989 
1990 	lwkt_gettoken(&ssb->ssb_token);
1991 	socantrcvmore(so);
1992 	asb = *ssb;
1993 
1994 	/*
1995 	 * Can't just blow up the ssb structure here
1996 	 */
1997 	bzero(&ssb->sb, sizeof(ssb->sb));
1998 	ssb->ssb_timeo = 0;
1999 	ssb->ssb_lowat = 0;
2000 	ssb->ssb_hiwat = 0;
2001 	ssb->ssb_mbmax = 0;
2002 	atomic_clear_int(&ssb->ssb_flags, SSB_CLEAR_MASK);
2003 
2004 	if ((pr->pr_flags & PR_RIGHTS) && pr->pr_domain->dom_dispose)
2005 		(*pr->pr_domain->dom_dispose)(asb.ssb_mb);
2006 	ssb_release(&asb, so);
2007 
2008 	lwkt_reltoken(&ssb->ssb_token);
2009 }
2010 
2011 #ifdef INET
2012 static int
2013 do_setopt_accept_filter(struct socket *so, struct sockopt *sopt)
2014 {
2015 	struct accept_filter_arg	*afap = NULL;
2016 	struct accept_filter	*afp;
2017 	struct so_accf	*af = so->so_accf;
2018 	int	error = 0;
2019 
2020 	/* do not set/remove accept filters on non listen sockets */
2021 	if ((so->so_options & SO_ACCEPTCONN) == 0) {
2022 		error = EINVAL;
2023 		goto out;
2024 	}
2025 
2026 	/* removing the filter */
2027 	if (sopt == NULL) {
2028 		if (af != NULL) {
2029 			if (af->so_accept_filter != NULL &&
2030 				af->so_accept_filter->accf_destroy != NULL) {
2031 				af->so_accept_filter->accf_destroy(so);
2032 			}
2033 			if (af->so_accept_filter_str != NULL) {
2034 				kfree(af->so_accept_filter_str, M_ACCF);
2035 			}
2036 			kfree(af, M_ACCF);
2037 			so->so_accf = NULL;
2038 		}
2039 		so->so_options &= ~SO_ACCEPTFILTER;
2040 		return (0);
2041 	}
2042 	/* adding a filter */
2043 	/* must remove previous filter first */
2044 	if (af != NULL) {
2045 		error = EINVAL;
2046 		goto out;
2047 	}
2048 	/* don't put large objects on the kernel stack */
2049 	afap = kmalloc(sizeof(*afap), M_TEMP, M_WAITOK);
2050 	error = sooptcopyin(sopt, afap, sizeof *afap, sizeof *afap);
2051 	afap->af_name[sizeof(afap->af_name)-1] = '\0';
2052 	afap->af_arg[sizeof(afap->af_arg)-1] = '\0';
2053 	if (error)
2054 		goto out;
2055 	afp = accept_filt_get(afap->af_name);
2056 	if (afp == NULL) {
2057 		error = ENOENT;
2058 		goto out;
2059 	}
2060 	af = kmalloc(sizeof(*af), M_ACCF, M_WAITOK | M_ZERO);
2061 	if (afp->accf_create != NULL) {
2062 		if (afap->af_name[0] != '\0') {
2063 			int len = strlen(afap->af_name) + 1;
2064 
2065 			af->so_accept_filter_str = kmalloc(len, M_ACCF,
2066 							   M_WAITOK);
2067 			strcpy(af->so_accept_filter_str, afap->af_name);
2068 		}
2069 		af->so_accept_filter_arg = afp->accf_create(so, afap->af_arg);
2070 		if (af->so_accept_filter_arg == NULL) {
2071 			kfree(af->so_accept_filter_str, M_ACCF);
2072 			kfree(af, M_ACCF);
2073 			so->so_accf = NULL;
2074 			error = EINVAL;
2075 			goto out;
2076 		}
2077 	}
2078 	af->so_accept_filter = afp;
2079 	so->so_accf = af;
2080 	so->so_options |= SO_ACCEPTFILTER;
2081 out:
2082 	if (afap != NULL)
2083 		kfree(afap, M_TEMP);
2084 	return (error);
2085 }
2086 #endif /* INET */
2087 
2088 /*
2089  * Perhaps this routine, and sooptcopyout(), below, ought to come in
2090  * an additional variant to handle the case where the option value needs
2091  * to be some kind of integer, but not a specific size.
2092  * In addition to their use here, these functions are also called by the
2093  * protocol-level pr_ctloutput() routines.
2094  */
2095 int
2096 sooptcopyin(struct sockopt *sopt, void *buf, size_t len, size_t minlen)
2097 {
2098 	return soopt_to_kbuf(sopt, buf, len, minlen);
2099 }
2100 
2101 int
2102 soopt_to_kbuf(struct sockopt *sopt, void *buf, size_t len, size_t minlen)
2103 {
2104 	size_t	valsize;
2105 
2106 	KKASSERT(!sopt->sopt_val || kva_p(sopt->sopt_val));
2107 	KKASSERT(kva_p(buf));
2108 
2109 	/*
2110 	 * If the user gives us more than we wanted, we ignore it,
2111 	 * but if we don't get the minimum length the caller
2112 	 * wants, we return EINVAL.  On success, sopt->sopt_valsize
2113 	 * is set to however much we actually retrieved.
2114 	 */
2115 	if ((valsize = sopt->sopt_valsize) < minlen)
2116 		return EINVAL;
2117 	if (valsize > len)
2118 		sopt->sopt_valsize = valsize = len;
2119 
2120 	bcopy(sopt->sopt_val, buf, valsize);
2121 	return 0;
2122 }
2123 
2124 
2125 int
2126 sosetopt(struct socket *so, struct sockopt *sopt)
2127 {
2128 	int	error, optval;
2129 	struct	linger l;
2130 	struct	timeval tv;
2131 	u_long  val;
2132 	struct signalsockbuf *sotmp;
2133 
2134 	error = 0;
2135 	sopt->sopt_dir = SOPT_SET;
2136 	if (sopt->sopt_level != SOL_SOCKET) {
2137 		if (so->so_proto && so->so_proto->pr_ctloutput) {
2138 			return (so_pr_ctloutput(so, sopt));
2139 		}
2140 		error = ENOPROTOOPT;
2141 	} else {
2142 		switch (sopt->sopt_name) {
2143 #ifdef INET
2144 		case SO_ACCEPTFILTER:
2145 			error = do_setopt_accept_filter(so, sopt);
2146 			if (error)
2147 				goto bad;
2148 			break;
2149 #endif /* INET */
2150 		case SO_LINGER:
2151 			error = sooptcopyin(sopt, &l, sizeof l, sizeof l);
2152 			if (error)
2153 				goto bad;
2154 
2155 			so->so_linger = l.l_linger;
2156 			if (l.l_onoff)
2157 				so->so_options |= SO_LINGER;
2158 			else
2159 				so->so_options &= ~SO_LINGER;
2160 			break;
2161 
2162 		case SO_DEBUG:
2163 		case SO_KEEPALIVE:
2164 		case SO_DONTROUTE:
2165 		case SO_USELOOPBACK:
2166 		case SO_BROADCAST:
2167 		case SO_REUSEADDR:
2168 		case SO_REUSEPORT:
2169 		case SO_OOBINLINE:
2170 		case SO_TIMESTAMP:
2171 		case SO_NOSIGPIPE:
2172 			error = sooptcopyin(sopt, &optval, sizeof optval,
2173 					    sizeof optval);
2174 			if (error)
2175 				goto bad;
2176 			if (optval)
2177 				so->so_options |= sopt->sopt_name;
2178 			else
2179 				so->so_options &= ~sopt->sopt_name;
2180 			break;
2181 
2182 		case SO_SNDBUF:
2183 		case SO_RCVBUF:
2184 		case SO_SNDLOWAT:
2185 		case SO_RCVLOWAT:
2186 			error = sooptcopyin(sopt, &optval, sizeof optval,
2187 					    sizeof optval);
2188 			if (error)
2189 				goto bad;
2190 
2191 			/*
2192 			 * Values < 1 make no sense for any of these
2193 			 * options, so disallow them.
2194 			 */
2195 			if (optval < 1) {
2196 				error = EINVAL;
2197 				goto bad;
2198 			}
2199 
2200 			switch (sopt->sopt_name) {
2201 			case SO_SNDBUF:
2202 			case SO_RCVBUF:
2203 				if (ssb_reserve(sopt->sopt_name == SO_SNDBUF ?
2204 				    &so->so_snd : &so->so_rcv, (u_long)optval,
2205 				    so,
2206 				    &curproc->p_rlimit[RLIMIT_SBSIZE]) == 0) {
2207 					error = ENOBUFS;
2208 					goto bad;
2209 				}
2210 				sotmp = (sopt->sopt_name == SO_SNDBUF) ?
2211 						&so->so_snd : &so->so_rcv;
2212 				atomic_clear_int(&sotmp->ssb_flags,
2213 						 SSB_AUTOSIZE);
2214 				break;
2215 
2216 			/*
2217 			 * Make sure the low-water is never greater than
2218 			 * the high-water.
2219 			 */
2220 			case SO_SNDLOWAT:
2221 				so->so_snd.ssb_lowat =
2222 				    (optval > so->so_snd.ssb_hiwat) ?
2223 				    so->so_snd.ssb_hiwat : optval;
2224 				atomic_clear_int(&so->so_snd.ssb_flags,
2225 						 SSB_AUTOLOWAT);
2226 				break;
2227 			case SO_RCVLOWAT:
2228 				so->so_rcv.ssb_lowat =
2229 				    (optval > so->so_rcv.ssb_hiwat) ?
2230 				    so->so_rcv.ssb_hiwat : optval;
2231 				atomic_clear_int(&so->so_rcv.ssb_flags,
2232 						 SSB_AUTOLOWAT);
2233 				break;
2234 			}
2235 			break;
2236 
2237 		case SO_SNDTIMEO:
2238 		case SO_RCVTIMEO:
2239 			error = sooptcopyin(sopt, &tv, sizeof tv,
2240 					    sizeof tv);
2241 			if (error)
2242 				goto bad;
2243 
2244 			/* assert(hz > 0); */
2245 			if (tv.tv_sec < 0 || tv.tv_sec > INT_MAX / hz ||
2246 			    tv.tv_usec < 0 || tv.tv_usec >= 1000000) {
2247 				error = EDOM;
2248 				goto bad;
2249 			}
2250 			/* assert(tick > 0); */
2251 			/* assert(ULONG_MAX - INT_MAX >= 1000000); */
2252 			val = (u_long)(tv.tv_sec * hz) + tv.tv_usec / ustick;
2253 			if (val > INT_MAX) {
2254 				error = EDOM;
2255 				goto bad;
2256 			}
2257 			if (val == 0 && tv.tv_usec != 0)
2258 				val = 1;
2259 
2260 			switch (sopt->sopt_name) {
2261 			case SO_SNDTIMEO:
2262 				so->so_snd.ssb_timeo = val;
2263 				break;
2264 			case SO_RCVTIMEO:
2265 				so->so_rcv.ssb_timeo = val;
2266 				break;
2267 			}
2268 			break;
2269 		default:
2270 			error = ENOPROTOOPT;
2271 			break;
2272 		}
2273 		if (error == 0 && so->so_proto && so->so_proto->pr_ctloutput) {
2274 			(void) so_pr_ctloutput(so, sopt);
2275 		}
2276 	}
2277 bad:
2278 	return (error);
2279 }
2280 
2281 /* Helper routine for getsockopt */
2282 int
2283 sooptcopyout(struct sockopt *sopt, const void *buf, size_t len)
2284 {
2285 	soopt_from_kbuf(sopt, buf, len);
2286 	return 0;
2287 }
2288 
2289 void
2290 soopt_from_kbuf(struct sockopt *sopt, const void *buf, size_t len)
2291 {
2292 	size_t	valsize;
2293 
2294 	if (len == 0) {
2295 		sopt->sopt_valsize = 0;
2296 		return;
2297 	}
2298 
2299 	KKASSERT(!sopt->sopt_val || kva_p(sopt->sopt_val));
2300 	KKASSERT(kva_p(buf));
2301 
2302 	/*
2303 	 * Documented get behavior is that we always return a value,
2304 	 * possibly truncated to fit in the user's buffer.
2305 	 * Traditional behavior is that we always tell the user
2306 	 * precisely how much we copied, rather than something useful
2307 	 * like the total amount we had available for her.
2308 	 * Note that this interface is not idempotent; the entire answer must
2309 	 * generated ahead of time.
2310 	 */
2311 	valsize = szmin(len, sopt->sopt_valsize);
2312 	sopt->sopt_valsize = valsize;
2313 	if (sopt->sopt_val != 0) {
2314 		bcopy(buf, sopt->sopt_val, valsize);
2315 	}
2316 }
2317 
2318 int
2319 sogetopt(struct socket *so, struct sockopt *sopt)
2320 {
2321 	int	error, optval;
2322 	long	optval_l;
2323 	struct	linger l;
2324 	struct	timeval tv;
2325 #ifdef INET
2326 	struct accept_filter_arg *afap;
2327 #endif
2328 
2329 	error = 0;
2330 	sopt->sopt_dir = SOPT_GET;
2331 	if (sopt->sopt_level != SOL_SOCKET) {
2332 		if (so->so_proto && so->so_proto->pr_ctloutput) {
2333 			return (so_pr_ctloutput(so, sopt));
2334 		} else
2335 			return (ENOPROTOOPT);
2336 	} else {
2337 		switch (sopt->sopt_name) {
2338 #ifdef INET
2339 		case SO_ACCEPTFILTER:
2340 			if ((so->so_options & SO_ACCEPTCONN) == 0)
2341 				return (EINVAL);
2342 			afap = kmalloc(sizeof(*afap), M_TEMP,
2343 				       M_WAITOK | M_ZERO);
2344 			if ((so->so_options & SO_ACCEPTFILTER) != 0) {
2345 				strcpy(afap->af_name, so->so_accf->so_accept_filter->accf_name);
2346 				if (so->so_accf->so_accept_filter_str != NULL)
2347 					strcpy(afap->af_arg, so->so_accf->so_accept_filter_str);
2348 			}
2349 			error = sooptcopyout(sopt, afap, sizeof(*afap));
2350 			kfree(afap, M_TEMP);
2351 			break;
2352 #endif /* INET */
2353 
2354 		case SO_LINGER:
2355 			l.l_onoff = so->so_options & SO_LINGER;
2356 			l.l_linger = so->so_linger;
2357 			error = sooptcopyout(sopt, &l, sizeof l);
2358 			break;
2359 
2360 		case SO_USELOOPBACK:
2361 		case SO_DONTROUTE:
2362 		case SO_DEBUG:
2363 		case SO_KEEPALIVE:
2364 		case SO_REUSEADDR:
2365 		case SO_REUSEPORT:
2366 		case SO_BROADCAST:
2367 		case SO_OOBINLINE:
2368 		case SO_TIMESTAMP:
2369 		case SO_NOSIGPIPE:
2370 			optval = so->so_options & sopt->sopt_name;
2371 integer:
2372 			error = sooptcopyout(sopt, &optval, sizeof optval);
2373 			break;
2374 
2375 		case SO_TYPE:
2376 			optval = so->so_type;
2377 			goto integer;
2378 
2379 		case SO_ERROR:
2380 			optval = so->so_error;
2381 			so->so_error = 0;
2382 			goto integer;
2383 
2384 		case SO_SNDBUF:
2385 			optval = so->so_snd.ssb_hiwat;
2386 			goto integer;
2387 
2388 		case SO_RCVBUF:
2389 			optval = so->so_rcv.ssb_hiwat;
2390 			goto integer;
2391 
2392 		case SO_SNDLOWAT:
2393 			optval = so->so_snd.ssb_lowat;
2394 			goto integer;
2395 
2396 		case SO_RCVLOWAT:
2397 			optval = so->so_rcv.ssb_lowat;
2398 			goto integer;
2399 
2400 		case SO_SNDTIMEO:
2401 		case SO_RCVTIMEO:
2402 			optval = (sopt->sopt_name == SO_SNDTIMEO ?
2403 				  so->so_snd.ssb_timeo : so->so_rcv.ssb_timeo);
2404 
2405 			tv.tv_sec = optval / hz;
2406 			tv.tv_usec = (optval % hz) * ustick;
2407 			error = sooptcopyout(sopt, &tv, sizeof tv);
2408 			break;
2409 
2410 		case SO_SNDSPACE:
2411 			optval_l = ssb_space(&so->so_snd);
2412 			error = sooptcopyout(sopt, &optval_l, sizeof(optval_l));
2413 			break;
2414 
2415 		default:
2416 			error = ENOPROTOOPT;
2417 			break;
2418 		}
2419 		return (error);
2420 	}
2421 }
2422 
2423 /* XXX; prepare mbuf for (__FreeBSD__ < 3) routines. */
2424 int
2425 soopt_getm(struct sockopt *sopt, struct mbuf **mp)
2426 {
2427 	struct mbuf *m, *m_prev;
2428 	int sopt_size = sopt->sopt_valsize, msize;
2429 
2430 	m = m_getl(sopt_size, sopt->sopt_td ? MB_WAIT : MB_DONTWAIT, MT_DATA,
2431 		   0, &msize);
2432 	if (m == NULL)
2433 		return (ENOBUFS);
2434 	m->m_len = min(msize, sopt_size);
2435 	sopt_size -= m->m_len;
2436 	*mp = m;
2437 	m_prev = m;
2438 
2439 	while (sopt_size > 0) {
2440 		m = m_getl(sopt_size, sopt->sopt_td ? MB_WAIT : MB_DONTWAIT,
2441 			   MT_DATA, 0, &msize);
2442 		if (m == NULL) {
2443 			m_freem(*mp);
2444 			return (ENOBUFS);
2445 		}
2446 		m->m_len = min(msize, sopt_size);
2447 		sopt_size -= m->m_len;
2448 		m_prev->m_next = m;
2449 		m_prev = m;
2450 	}
2451 	return (0);
2452 }
2453 
2454 /* XXX; copyin sopt data into mbuf chain for (__FreeBSD__ < 3) routines. */
2455 int
2456 soopt_mcopyin(struct sockopt *sopt, struct mbuf *m)
2457 {
2458 	soopt_to_mbuf(sopt, m);
2459 	return 0;
2460 }
2461 
2462 void
2463 soopt_to_mbuf(struct sockopt *sopt, struct mbuf *m)
2464 {
2465 	size_t valsize;
2466 	void *val;
2467 
2468 	KKASSERT(!sopt->sopt_val || kva_p(sopt->sopt_val));
2469 	KKASSERT(kva_p(m));
2470 	if (sopt->sopt_val == NULL)
2471 		return;
2472 	val = sopt->sopt_val;
2473 	valsize = sopt->sopt_valsize;
2474 	while (m != NULL && valsize >= m->m_len) {
2475 		bcopy(val, mtod(m, char *), m->m_len);
2476 		valsize -= m->m_len;
2477 		val = (caddr_t)val + m->m_len;
2478 		m = m->m_next;
2479 	}
2480 	if (m != NULL) /* should be allocated enoughly at ip6_sooptmcopyin() */
2481 		panic("ip6_sooptmcopyin");
2482 }
2483 
2484 /* XXX; copyout mbuf chain data into soopt for (__FreeBSD__ < 3) routines. */
2485 int
2486 soopt_mcopyout(struct sockopt *sopt, struct mbuf *m)
2487 {
2488 	return soopt_from_mbuf(sopt, m);
2489 }
2490 
2491 int
2492 soopt_from_mbuf(struct sockopt *sopt, struct mbuf *m)
2493 {
2494 	struct mbuf *m0 = m;
2495 	size_t valsize = 0;
2496 	size_t maxsize;
2497 	void *val;
2498 
2499 	KKASSERT(!sopt->sopt_val || kva_p(sopt->sopt_val));
2500 	KKASSERT(kva_p(m));
2501 	if (sopt->sopt_val == NULL)
2502 		return 0;
2503 	val = sopt->sopt_val;
2504 	maxsize = sopt->sopt_valsize;
2505 	while (m != NULL && maxsize >= m->m_len) {
2506 		bcopy(mtod(m, char *), val, m->m_len);
2507 	       maxsize -= m->m_len;
2508 	       val = (caddr_t)val + m->m_len;
2509 	       valsize += m->m_len;
2510 	       m = m->m_next;
2511 	}
2512 	if (m != NULL) {
2513 		/* enough soopt buffer should be given from user-land */
2514 		m_freem(m0);
2515 		return (EINVAL);
2516 	}
2517 	sopt->sopt_valsize = valsize;
2518 	return 0;
2519 }
2520 
2521 void
2522 sohasoutofband(struct socket *so)
2523 {
2524 	if (so->so_sigio != NULL)
2525 		pgsigio(so->so_sigio, SIGURG, 0);
2526 	KNOTE(&so->so_rcv.ssb_kq.ki_note, NOTE_OOB);
2527 }
2528 
2529 int
2530 sokqfilter(struct file *fp, struct knote *kn)
2531 {
2532 	struct socket *so = (struct socket *)kn->kn_fp->f_data;
2533 	struct signalsockbuf *ssb;
2534 
2535 	switch (kn->kn_filter) {
2536 	case EVFILT_READ:
2537 		if (so->so_options & SO_ACCEPTCONN)
2538 			kn->kn_fop = &solisten_filtops;
2539 		else
2540 			kn->kn_fop = &soread_filtops;
2541 		ssb = &so->so_rcv;
2542 		break;
2543 	case EVFILT_WRITE:
2544 		kn->kn_fop = &sowrite_filtops;
2545 		ssb = &so->so_snd;
2546 		break;
2547 	case EVFILT_EXCEPT:
2548 		kn->kn_fop = &soexcept_filtops;
2549 		ssb = &so->so_rcv;
2550 		break;
2551 	default:
2552 		return (EOPNOTSUPP);
2553 	}
2554 
2555 	knote_insert(&ssb->ssb_kq.ki_note, kn);
2556 	atomic_set_int(&ssb->ssb_flags, SSB_KNOTE);
2557 	return (0);
2558 }
2559 
2560 static void
2561 filt_sordetach(struct knote *kn)
2562 {
2563 	struct socket *so = (struct socket *)kn->kn_fp->f_data;
2564 
2565 	knote_remove(&so->so_rcv.ssb_kq.ki_note, kn);
2566 	if (SLIST_EMPTY(&so->so_rcv.ssb_kq.ki_note))
2567 		atomic_clear_int(&so->so_rcv.ssb_flags, SSB_KNOTE);
2568 }
2569 
2570 /*ARGSUSED*/
2571 static int
2572 filt_soread(struct knote *kn, long hint)
2573 {
2574 	struct socket *so = (struct socket *)kn->kn_fp->f_data;
2575 
2576 	if (kn->kn_sfflags & NOTE_OOB) {
2577 		if ((so->so_oobmark || (so->so_state & SS_RCVATMARK))) {
2578 			kn->kn_fflags |= NOTE_OOB;
2579 			return (1);
2580 		}
2581 		return (0);
2582 	}
2583 	kn->kn_data = so->so_rcv.ssb_cc;
2584 
2585 	if (so->so_state & SS_CANTRCVMORE) {
2586 		/*
2587 		 * Only set NODATA if all data has been exhausted.
2588 		 */
2589 		if (kn->kn_data == 0)
2590 			kn->kn_flags |= EV_NODATA;
2591 		kn->kn_flags |= EV_EOF;
2592 		kn->kn_fflags = so->so_error;
2593 		return (1);
2594 	}
2595 	if (so->so_error)	/* temporary udp error */
2596 		return (1);
2597 	if (kn->kn_sfflags & NOTE_LOWAT)
2598 		return (kn->kn_data >= kn->kn_sdata);
2599 	return ((kn->kn_data >= so->so_rcv.ssb_lowat) ||
2600 		!TAILQ_EMPTY(&so->so_comp));
2601 }
2602 
2603 static void
2604 filt_sowdetach(struct knote *kn)
2605 {
2606 	struct socket *so = (struct socket *)kn->kn_fp->f_data;
2607 
2608 	knote_remove(&so->so_snd.ssb_kq.ki_note, kn);
2609 	if (SLIST_EMPTY(&so->so_snd.ssb_kq.ki_note))
2610 		atomic_clear_int(&so->so_snd.ssb_flags, SSB_KNOTE);
2611 }
2612 
2613 /*ARGSUSED*/
2614 static int
2615 filt_sowrite(struct knote *kn, long hint)
2616 {
2617 	struct socket *so = (struct socket *)kn->kn_fp->f_data;
2618 
2619 	kn->kn_data = ssb_space(&so->so_snd);
2620 	if (so->so_state & SS_CANTSENDMORE) {
2621 		kn->kn_flags |= (EV_EOF | EV_NODATA);
2622 		kn->kn_fflags = so->so_error;
2623 		return (1);
2624 	}
2625 	if (so->so_error)	/* temporary udp error */
2626 		return (1);
2627 	if (((so->so_state & SS_ISCONNECTED) == 0) &&
2628 	    (so->so_proto->pr_flags & PR_CONNREQUIRED))
2629 		return (0);
2630 	if (kn->kn_sfflags & NOTE_LOWAT)
2631 		return (kn->kn_data >= kn->kn_sdata);
2632 	return (kn->kn_data >= so->so_snd.ssb_lowat);
2633 }
2634 
2635 /*ARGSUSED*/
2636 static int
2637 filt_solisten(struct knote *kn, long hint)
2638 {
2639 	struct socket *so = (struct socket *)kn->kn_fp->f_data;
2640 
2641 	kn->kn_data = so->so_qlen;
2642 	return (! TAILQ_EMPTY(&so->so_comp));
2643 }
2644