xref: /dragonfly/sys/kern/uipc_syscalls.c (revision ed5d5720)
1 /*
2  * Copyright (c) 1982, 1986, 1989, 1990, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * sendfile(2) and related extensions:
6  * Copyright (c) 1998, David Greenman. All rights reserved.
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. All advertising materials mentioning features or use of this software
17  *    must display the following acknowledgement:
18  *	This product includes software developed by the University of
19  *	California, Berkeley and its contributors.
20  * 4. Neither the name of the University nor the names of its contributors
21  *    may be used to endorse or promote products derived from this software
22  *    without specific prior written permission.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34  * SUCH DAMAGE.
35  *
36  *	@(#)uipc_syscalls.c	8.4 (Berkeley) 2/21/94
37  * $FreeBSD: src/sys/kern/uipc_syscalls.c,v 1.65.2.17 2003/04/04 17:11:16 tegge Exp $
38  * $DragonFly: src/sys/kern/uipc_syscalls.c,v 1.92 2008/11/26 13:10:56 sephe Exp $
39  */
40 
41 #include "opt_ktrace.h"
42 #include "opt_sctp.h"
43 
44 #include <sys/param.h>
45 #include <sys/systm.h>
46 #include <sys/kernel.h>
47 #include <sys/sysproto.h>
48 #include <sys/malloc.h>
49 #include <sys/filedesc.h>
50 #include <sys/event.h>
51 #include <sys/proc.h>
52 #include <sys/fcntl.h>
53 #include <sys/file.h>
54 #include <sys/filio.h>
55 #include <sys/kern_syscall.h>
56 #include <sys/mbuf.h>
57 #include <sys/protosw.h>
58 #include <sys/sfbuf.h>
59 #include <sys/socket.h>
60 #include <sys/socketvar.h>
61 #include <sys/socketops.h>
62 #include <sys/uio.h>
63 #include <sys/vnode.h>
64 #include <sys/lock.h>
65 #include <sys/mount.h>
66 #ifdef KTRACE
67 #include <sys/ktrace.h>
68 #endif
69 #include <vm/vm.h>
70 #include <vm/vm_object.h>
71 #include <vm/vm_page.h>
72 #include <vm/vm_pageout.h>
73 #include <vm/vm_kern.h>
74 #include <vm/vm_extern.h>
75 #include <sys/file2.h>
76 #include <sys/signalvar.h>
77 #include <sys/serialize.h>
78 
79 #include <sys/thread2.h>
80 #include <sys/msgport2.h>
81 #include <sys/socketvar2.h>
82 #include <net/netmsg2.h>
83 
84 #ifdef SCTP
85 #include <netinet/sctp_peeloff.h>
86 #endif /* SCTP */
87 
88 struct sfbuf_mref {
89 	struct sf_buf	*sf;
90 	int		mref_count;
91 };
92 
93 static MALLOC_DEFINE(M_SENDFILE, "sendfile", "sendfile sfbuf ref structures");
94 
95 /*
96  * System call interface to the socket abstraction.
97  */
98 
99 extern	struct fileops socketops;
100 
101 /*
102  * socket_args(int domain, int type, int protocol)
103  */
104 int
105 kern_socket(int domain, int type, int protocol, int *res)
106 {
107 	struct thread *td = curthread;
108 	struct proc *p = td->td_proc;
109 	struct socket *so;
110 	struct file *fp;
111 	int fd, error;
112 
113 	KKASSERT(p);
114 
115 	error = falloc(p, &fp, &fd);
116 	if (error)
117 		return (error);
118 	error = socreate(domain, &so, type, protocol, td);
119 	if (error) {
120 		fsetfd(p, NULL, fd);
121 	} else {
122 		fp->f_type = DTYPE_SOCKET;
123 		fp->f_flag = FREAD | FWRITE;
124 		fp->f_ops = &socketops;
125 		fp->f_data = so;
126 		*res = fd;
127 		fsetfd(p, fp, fd);
128 	}
129 	fdrop(fp);
130 	return (error);
131 }
132 
133 int
134 sys_socket(struct socket_args *uap)
135 {
136 	int error;
137 
138 	error = kern_socket(uap->domain, uap->type, uap->protocol,
139 	    &uap->sysmsg_result);
140 
141 	return (error);
142 }
143 
144 int
145 kern_bind(int s, struct sockaddr *sa)
146 {
147 	struct thread *td = curthread;
148 	struct proc *p = td->td_proc;
149 	struct file *fp;
150 	int error;
151 
152 	KKASSERT(p);
153 	error = holdsock(p->p_fd, s, &fp);
154 	if (error)
155 		return (error);
156 	error = sobind((struct socket *)fp->f_data, sa, td);
157 	fdrop(fp);
158 	return (error);
159 }
160 
161 /*
162  * bind_args(int s, caddr_t name, int namelen)
163  */
164 int
165 sys_bind(struct bind_args *uap)
166 {
167 	struct sockaddr *sa;
168 	int error;
169 
170 	error = getsockaddr(&sa, uap->name, uap->namelen);
171 	if (error)
172 		return (error);
173 	error = kern_bind(uap->s, sa);
174 	FREE(sa, M_SONAME);
175 
176 	return (error);
177 }
178 
179 int
180 kern_listen(int s, int backlog)
181 {
182 	struct thread *td = curthread;
183 	struct proc *p = td->td_proc;
184 	struct file *fp;
185 	int error;
186 
187 	KKASSERT(p);
188 	error = holdsock(p->p_fd, s, &fp);
189 	if (error)
190 		return (error);
191 	error = solisten((struct socket *)fp->f_data, backlog, td);
192 	fdrop(fp);
193 	return(error);
194 }
195 
196 /*
197  * listen_args(int s, int backlog)
198  */
199 int
200 sys_listen(struct listen_args *uap)
201 {
202 	int error;
203 
204 	error = kern_listen(uap->s, uap->backlog);
205 	return (error);
206 }
207 
208 /*
209  * Returns the accepted socket as well.
210  */
211 static boolean_t
212 soaccept_predicate(struct netmsg *msg0)
213 {
214 	struct netmsg_so_notify *msg = (struct netmsg_so_notify *)msg0;
215 	struct socket *head = msg->nm_so;
216 
217 	if (head->so_error != 0) {
218 		msg->nm_netmsg.nm_lmsg.ms_error = head->so_error;
219 		return (TRUE);
220 	}
221 	if (!TAILQ_EMPTY(&head->so_comp)) {
222 		/* Abuse nm_so field as copy in/copy out parameter. XXX JH */
223 		msg->nm_so = TAILQ_FIRST(&head->so_comp);
224 		TAILQ_REMOVE(&head->so_comp, msg->nm_so, so_list);
225 		head->so_qlen--;
226 
227 		msg->nm_netmsg.nm_lmsg.ms_error = 0;
228 		return (TRUE);
229 	}
230 	if (head->so_state & SS_CANTRCVMORE) {
231 		msg->nm_netmsg.nm_lmsg.ms_error = ECONNABORTED;
232 		return (TRUE);
233 	}
234 	if (msg->nm_fflags & FNONBLOCK) {
235 		msg->nm_netmsg.nm_lmsg.ms_error = EWOULDBLOCK;
236 		return (TRUE);
237 	}
238 
239 	return (FALSE);
240 }
241 
242 /*
243  * The second argument to kern_accept() is a handle to a struct sockaddr.
244  * This allows kern_accept() to return a pointer to an allocated struct
245  * sockaddr which must be freed later with FREE().  The caller must
246  * initialize *name to NULL.
247  */
248 int
249 kern_accept(int s, int fflags, struct sockaddr **name, int *namelen, int *res)
250 {
251 	struct thread *td = curthread;
252 	struct proc *p = td->td_proc;
253 	struct file *lfp = NULL;
254 	struct file *nfp = NULL;
255 	struct sockaddr *sa;
256 	struct socket *head, *so;
257 	struct netmsg_so_notify msg;
258 	lwkt_port_t port;
259 	int fd;
260 	u_int fflag;		/* type must match fp->f_flag */
261 	int error, tmp;
262 
263 	*res = -1;
264 	if (name && namelen && *namelen < 0)
265 		return (EINVAL);
266 
267 	error = holdsock(p->p_fd, s, &lfp);
268 	if (error)
269 		return (error);
270 
271 	error = falloc(p, &nfp, &fd);
272 	if (error) {		/* Probably ran out of file descriptors. */
273 		fdrop(lfp);
274 		return (error);
275 	}
276 	head = (struct socket *)lfp->f_data;
277 	if ((head->so_options & SO_ACCEPTCONN) == 0) {
278 		error = EINVAL;
279 		goto done;
280 	}
281 
282 	if (fflags & O_FBLOCKING)
283 		fflags |= lfp->f_flag & ~FNONBLOCK;
284 	else if (fflags & O_FNONBLOCKING)
285 		fflags |= lfp->f_flag | FNONBLOCK;
286 	else
287 		fflags = lfp->f_flag;
288 
289 	/* optimize for uniprocessor case later XXX JH */
290 	port = head->so_proto->pr_mport(head, NULL, NULL, PRU_PRED);
291 	netmsg_init_abortable(&msg.nm_netmsg, &curthread->td_msgport,
292 			      0,
293 			      netmsg_so_notify,
294 			      netmsg_so_notify_doabort);
295 	msg.nm_predicate = soaccept_predicate;
296 	msg.nm_fflags = fflags;
297 	msg.nm_so = head;
298 	msg.nm_etype = NM_REVENT;
299 	error = lwkt_domsg(port, &msg.nm_netmsg.nm_lmsg, PCATCH);
300 	if (error)
301 		goto done;
302 
303 	/*
304 	 * At this point we have the connection that's ready to be accepted.
305 	 */
306 	so = msg.nm_so;
307 
308 	fflag = lfp->f_flag;
309 
310 	/* connection has been removed from the listen queue */
311 	KNOTE(&head->so_rcv.ssb_sel.si_note, 0);
312 
313 	so->so_state &= ~SS_COMP;
314 	so->so_head = NULL;
315 	if (head->so_sigio != NULL)
316 		fsetown(fgetown(head->so_sigio), &so->so_sigio);
317 
318 	nfp->f_type = DTYPE_SOCKET;
319 	nfp->f_flag = fflag;
320 	nfp->f_ops = &socketops;
321 	nfp->f_data = so;
322 	/* Sync socket nonblocking/async state with file flags */
323 	tmp = fflag & FNONBLOCK;
324 	(void) fo_ioctl(nfp, FIONBIO, (caddr_t)&tmp, p->p_ucred);
325 	tmp = fflag & FASYNC;
326 	(void) fo_ioctl(nfp, FIOASYNC, (caddr_t)&tmp, p->p_ucred);
327 
328 	sa = NULL;
329 	error = soaccept(so, &sa);
330 
331 	/*
332 	 * Set the returned name and namelen as applicable.  Set the returned
333 	 * namelen to 0 for older code which might ignore the return value
334 	 * from accept.
335 	 */
336 	if (error == 0) {
337 		if (sa && name && namelen) {
338 			if (*namelen > sa->sa_len)
339 				*namelen = sa->sa_len;
340 			*name = sa;
341 		} else {
342 			if (sa)
343 				FREE(sa, M_SONAME);
344 		}
345 	}
346 
347 done:
348 	/*
349 	 * If an error occured clear the reserved descriptor, else associate
350 	 * nfp with it.
351 	 *
352 	 * Note that *res is normally ignored if an error is returned but
353 	 * a syscall message will still have access to the result code.
354 	 */
355 	if (error) {
356 		fsetfd(p, NULL, fd);
357 	} else {
358 		*res = fd;
359 		fsetfd(p, nfp, fd);
360 	}
361 	fdrop(nfp);
362 	fdrop(lfp);
363 	return (error);
364 }
365 
366 /*
367  * accept(int s, caddr_t name, int *anamelen)
368  */
369 int
370 sys_accept(struct accept_args *uap)
371 {
372 	struct sockaddr *sa = NULL;
373 	int sa_len;
374 	int error;
375 
376 	if (uap->name) {
377 		error = copyin(uap->anamelen, &sa_len, sizeof(sa_len));
378 		if (error)
379 			return (error);
380 
381 		error = kern_accept(uap->s, 0, &sa, &sa_len, &uap->sysmsg_result);
382 
383 		if (error == 0)
384 			error = copyout(sa, uap->name, sa_len);
385 		if (error == 0) {
386 			error = copyout(&sa_len, uap->anamelen,
387 			    sizeof(*uap->anamelen));
388 		}
389 		if (sa)
390 			FREE(sa, M_SONAME);
391 	} else {
392 		error = kern_accept(uap->s, 0, NULL, 0, &uap->sysmsg_result);
393 	}
394 	return (error);
395 }
396 
397 /*
398  * extaccept(int s, int fflags, caddr_t name, int *anamelen)
399  */
400 int
401 sys_extaccept(struct extaccept_args *uap)
402 {
403 	struct sockaddr *sa = NULL;
404 	int sa_len;
405 	int error;
406 	int fflags = uap->flags & O_FMASK;
407 
408 	if (uap->name) {
409 		error = copyin(uap->anamelen, &sa_len, sizeof(sa_len));
410 		if (error)
411 			return (error);
412 
413 		error = kern_accept(uap->s, fflags, &sa, &sa_len, &uap->sysmsg_result);
414 
415 		if (error == 0)
416 			error = copyout(sa, uap->name, sa_len);
417 		if (error == 0) {
418 			error = copyout(&sa_len, uap->anamelen,
419 			    sizeof(*uap->anamelen));
420 		}
421 		if (sa)
422 			FREE(sa, M_SONAME);
423 	} else {
424 		error = kern_accept(uap->s, fflags, NULL, 0, &uap->sysmsg_result);
425 	}
426 	return (error);
427 }
428 
429 
430 /*
431  * Returns TRUE if predicate satisfied.
432  */
433 static boolean_t
434 soconnected_predicate(struct netmsg *msg0)
435 {
436 	struct netmsg_so_notify *msg = (struct netmsg_so_notify *)msg0;
437 	struct socket *so = msg->nm_so;
438 
439 	/* check predicate */
440 	if (!(so->so_state & SS_ISCONNECTING) || so->so_error != 0) {
441 		msg->nm_netmsg.nm_lmsg.ms_error = so->so_error;
442 		return (TRUE);
443 	}
444 
445 	return (FALSE);
446 }
447 
448 int
449 kern_connect(int s, int fflags, struct sockaddr *sa)
450 {
451 	struct thread *td = curthread;
452 	struct proc *p = td->td_proc;
453 	struct file *fp;
454 	struct socket *so;
455 	int error, interrupted = 0;
456 
457 	error = holdsock(p->p_fd, s, &fp);
458 	if (error)
459 		return (error);
460 	so = (struct socket *)fp->f_data;
461 
462 	if (fflags & O_FBLOCKING)
463 		/* fflags &= ~FNONBLOCK; */;
464 	else if (fflags & O_FNONBLOCKING)
465 		fflags |= FNONBLOCK;
466 	else
467 		fflags = fp->f_flag;
468 
469 	if (so->so_state & SS_ISCONNECTING) {
470 		error = EALREADY;
471 		goto done;
472 	}
473 	error = soconnect(so, sa, td);
474 	if (error)
475 		goto bad;
476 	if ((fflags & FNONBLOCK) && (so->so_state & SS_ISCONNECTING)) {
477 		error = EINPROGRESS;
478 		goto done;
479 	}
480 	if ((so->so_state & SS_ISCONNECTING) && so->so_error == 0) {
481 		struct netmsg_so_notify msg;
482 		lwkt_port_t port;
483 
484 		port = so->so_proto->pr_mport(so, sa, NULL, PRU_PRED);
485 		netmsg_init_abortable(&msg.nm_netmsg,
486 				      &curthread->td_msgport,
487 				      0,
488 				      netmsg_so_notify,
489 				      netmsg_so_notify_doabort);
490 		msg.nm_predicate = soconnected_predicate;
491 		msg.nm_so = so;
492 		msg.nm_etype = NM_REVENT;
493 		error = lwkt_domsg(port, &msg.nm_netmsg.nm_lmsg, PCATCH);
494 		if (error == EINTR || error == ERESTART)
495 			interrupted = 1;
496 	}
497 	if (error == 0) {
498 		error = so->so_error;
499 		so->so_error = 0;
500 	}
501 bad:
502 	if (!interrupted)
503 		so->so_state &= ~SS_ISCONNECTING;
504 	if (error == ERESTART)
505 		error = EINTR;
506 done:
507 	fdrop(fp);
508 	return (error);
509 }
510 
511 /*
512  * connect_args(int s, caddr_t name, int namelen)
513  */
514 int
515 sys_connect(struct connect_args *uap)
516 {
517 	struct sockaddr *sa;
518 	int error;
519 
520 	error = getsockaddr(&sa, uap->name, uap->namelen);
521 	if (error)
522 		return (error);
523 	error = kern_connect(uap->s, 0, sa);
524 	FREE(sa, M_SONAME);
525 
526 	return (error);
527 }
528 
529 /*
530  * connect_args(int s, int fflags, caddr_t name, int namelen)
531  */
532 int
533 sys_extconnect(struct extconnect_args *uap)
534 {
535 	struct sockaddr *sa;
536 	int error;
537 	int fflags = uap->flags & O_FMASK;
538 
539 	error = getsockaddr(&sa, uap->name, uap->namelen);
540 	if (error)
541 		return (error);
542 	error = kern_connect(uap->s, fflags, sa);
543 	FREE(sa, M_SONAME);
544 
545 	return (error);
546 }
547 
548 int
549 kern_socketpair(int domain, int type, int protocol, int *sv)
550 {
551 	struct thread *td = curthread;
552 	struct proc *p = td->td_proc;
553 	struct file *fp1, *fp2;
554 	struct socket *so1, *so2;
555 	int fd1, fd2, error;
556 
557 	KKASSERT(p);
558 	error = socreate(domain, &so1, type, protocol, td);
559 	if (error)
560 		return (error);
561 	error = socreate(domain, &so2, type, protocol, td);
562 	if (error)
563 		goto free1;
564 	error = falloc(p, &fp1, &fd1);
565 	if (error)
566 		goto free2;
567 	sv[0] = fd1;
568 	fp1->f_data = so1;
569 	error = falloc(p, &fp2, &fd2);
570 	if (error)
571 		goto free3;
572 	fp2->f_data = so2;
573 	sv[1] = fd2;
574 	error = soconnect2(so1, so2);
575 	if (error)
576 		goto free4;
577 	if (type == SOCK_DGRAM) {
578 		/*
579 		 * Datagram socket connection is asymmetric.
580 		 */
581 		 error = soconnect2(so2, so1);
582 		 if (error)
583 			goto free4;
584 	}
585 	fp1->f_type = fp2->f_type = DTYPE_SOCKET;
586 	fp1->f_flag = fp2->f_flag = FREAD|FWRITE;
587 	fp1->f_ops = fp2->f_ops = &socketops;
588 	fsetfd(p, fp1, fd1);
589 	fsetfd(p, fp2, fd2);
590 	fdrop(fp1);
591 	fdrop(fp2);
592 	return (error);
593 free4:
594 	fsetfd(p, NULL, fd2);
595 	fdrop(fp2);
596 free3:
597 	fsetfd(p, NULL, fd1);
598 	fdrop(fp1);
599 free2:
600 	(void)soclose(so2, 0);
601 free1:
602 	(void)soclose(so1, 0);
603 	return (error);
604 }
605 
606 /*
607  * socketpair(int domain, int type, int protocol, int *rsv)
608  */
609 int
610 sys_socketpair(struct socketpair_args *uap)
611 {
612 	int error, sockv[2];
613 
614 	error = kern_socketpair(uap->domain, uap->type, uap->protocol, sockv);
615 
616 	if (error == 0)
617 		error = copyout(sockv, uap->rsv, sizeof(sockv));
618 	return (error);
619 }
620 
621 int
622 kern_sendmsg(int s, struct sockaddr *sa, struct uio *auio,
623     struct mbuf *control, int flags, int *res)
624 {
625 	struct thread *td = curthread;
626 	struct lwp *lp = td->td_lwp;
627 	struct proc *p = td->td_proc;
628 	struct file *fp;
629 	int len, error;
630 	struct socket *so;
631 #ifdef KTRACE
632 	struct iovec *ktriov = NULL;
633 	struct uio ktruio;
634 #endif
635 
636 	error = holdsock(p->p_fd, s, &fp);
637 	if (error)
638 		return (error);
639 	if (auio->uio_resid < 0) {
640 		error = EINVAL;
641 		goto done;
642 	}
643 #ifdef KTRACE
644 	if (KTRPOINT(td, KTR_GENIO)) {
645 		int iovlen = auio->uio_iovcnt * sizeof (struct iovec);
646 
647 		MALLOC(ktriov, struct iovec *, iovlen, M_TEMP, M_WAITOK);
648 		bcopy((caddr_t)auio->uio_iov, (caddr_t)ktriov, iovlen);
649 		ktruio = *auio;
650 	}
651 #endif
652 	len = auio->uio_resid;
653 	so = (struct socket *)fp->f_data;
654 	if ((flags & (MSG_FNONBLOCKING|MSG_FBLOCKING)) == 0) {
655 		if (fp->f_flag & FNONBLOCK)
656 			flags |= MSG_FNONBLOCKING;
657 	}
658 	error = so_pru_sosend(so, sa, auio, NULL, control, flags, td);
659 	if (error) {
660 		if (auio->uio_resid != len && (error == ERESTART ||
661 		    error == EINTR || error == EWOULDBLOCK))
662 			error = 0;
663 		if (error == EPIPE)
664 			lwpsignal(p, lp, SIGPIPE);
665 	}
666 #ifdef KTRACE
667 	if (ktriov != NULL) {
668 		if (error == 0) {
669 			ktruio.uio_iov = ktriov;
670 			ktruio.uio_resid = len - auio->uio_resid;
671 			ktrgenio(lp, s, UIO_WRITE, &ktruio, error);
672 		}
673 		FREE(ktriov, M_TEMP);
674 	}
675 #endif
676 	if (error == 0)
677 		*res  = len - auio->uio_resid;
678 done:
679 	fdrop(fp);
680 	return (error);
681 }
682 
683 /*
684  * sendto_args(int s, caddr_t buf, size_t len, int flags, caddr_t to, int tolen)
685  */
686 int
687 sys_sendto(struct sendto_args *uap)
688 {
689 	struct thread *td = curthread;
690 	struct uio auio;
691 	struct iovec aiov;
692 	struct sockaddr *sa = NULL;
693 	int error;
694 
695 	if (uap->to) {
696 		error = getsockaddr(&sa, uap->to, uap->tolen);
697 		if (error)
698 			return (error);
699 	}
700 	aiov.iov_base = uap->buf;
701 	aiov.iov_len = uap->len;
702 	auio.uio_iov = &aiov;
703 	auio.uio_iovcnt = 1;
704 	auio.uio_offset = 0;
705 	auio.uio_resid = uap->len;
706 	auio.uio_segflg = UIO_USERSPACE;
707 	auio.uio_rw = UIO_WRITE;
708 	auio.uio_td = td;
709 
710 	error = kern_sendmsg(uap->s, sa, &auio, NULL, uap->flags,
711 	    &uap->sysmsg_result);
712 
713 	if (sa)
714 		FREE(sa, M_SONAME);
715 	return (error);
716 }
717 
718 /*
719  * sendmsg_args(int s, caddr_t msg, int flags)
720  */
721 int
722 sys_sendmsg(struct sendmsg_args *uap)
723 {
724 	struct thread *td = curthread;
725 	struct msghdr msg;
726 	struct uio auio;
727 	struct iovec aiov[UIO_SMALLIOV], *iov = NULL;
728 	struct sockaddr *sa = NULL;
729 	struct mbuf *control = NULL;
730 	int error;
731 
732 	error = copyin(uap->msg, (caddr_t)&msg, sizeof(msg));
733 	if (error)
734 		return (error);
735 
736 	/*
737 	 * Conditionally copyin msg.msg_name.
738 	 */
739 	if (msg.msg_name) {
740 		error = getsockaddr(&sa, msg.msg_name, msg.msg_namelen);
741 		if (error)
742 			return (error);
743 	}
744 
745 	/*
746 	 * Populate auio.
747 	 */
748 	error = iovec_copyin(msg.msg_iov, &iov, aiov, msg.msg_iovlen,
749 			     &auio.uio_resid);
750 	if (error)
751 		goto cleanup2;
752 	auio.uio_iov = iov;
753 	auio.uio_iovcnt = msg.msg_iovlen;
754 	auio.uio_offset = 0;
755 	auio.uio_segflg = UIO_USERSPACE;
756 	auio.uio_rw = UIO_WRITE;
757 	auio.uio_td = td;
758 
759 	/*
760 	 * Conditionally copyin msg.msg_control.
761 	 */
762 	if (msg.msg_control) {
763 		if (msg.msg_controllen < sizeof(struct cmsghdr) ||
764 		    msg.msg_controllen > MLEN) {
765 			error = EINVAL;
766 			goto cleanup;
767 		}
768 		control = m_get(MB_WAIT, MT_CONTROL);
769 		if (control == NULL) {
770 			error = ENOBUFS;
771 			goto cleanup;
772 		}
773 		control->m_len = msg.msg_controllen;
774 		error = copyin(msg.msg_control, mtod(control, caddr_t),
775 		    msg.msg_controllen);
776 		if (error) {
777 			m_free(control);
778 			goto cleanup;
779 		}
780 	}
781 
782 	error = kern_sendmsg(uap->s, sa, &auio, control, uap->flags,
783 	    &uap->sysmsg_result);
784 
785 cleanup:
786 	iovec_free(&iov, aiov);
787 cleanup2:
788 	if (sa)
789 		FREE(sa, M_SONAME);
790 	return (error);
791 }
792 
793 /*
794  * kern_recvmsg() takes a handle to sa and control.  If the handle is non-
795  * null, it returns a dynamically allocated struct sockaddr and an mbuf.
796  * Don't forget to FREE() and m_free() these if they are returned.
797  */
798 int
799 kern_recvmsg(int s, struct sockaddr **sa, struct uio *auio,
800     struct mbuf **control, int *flags, int *res)
801 {
802 	struct thread *td = curthread;
803 	struct proc *p = td->td_proc;
804 	struct file *fp;
805 	int len, error;
806 	int lflags;
807 	struct socket *so;
808 #ifdef KTRACE
809 	struct iovec *ktriov = NULL;
810 	struct uio ktruio;
811 #endif
812 
813 	error = holdsock(p->p_fd, s, &fp);
814 	if (error)
815 		return (error);
816 	if (auio->uio_resid < 0) {
817 		error = EINVAL;
818 		goto done;
819 	}
820 #ifdef KTRACE
821 	if (KTRPOINT(td, KTR_GENIO)) {
822 		int iovlen = auio->uio_iovcnt * sizeof (struct iovec);
823 
824 		MALLOC(ktriov, struct iovec *, iovlen, M_TEMP, M_WAITOK);
825 		bcopy(auio->uio_iov, ktriov, iovlen);
826 		ktruio = *auio;
827 	}
828 #endif
829 	len = auio->uio_resid;
830 	so = (struct socket *)fp->f_data;
831 
832 	if (flags == NULL || (*flags & (MSG_FNONBLOCKING|MSG_FBLOCKING)) == 0) {
833 		if (fp->f_flag & FNONBLOCK) {
834 			if (flags) {
835 				*flags |= MSG_FNONBLOCKING;
836 			} else {
837 				lflags = MSG_FNONBLOCKING;
838 				flags = &lflags;
839 			}
840 		}
841 	}
842 
843 	error = so_pru_soreceive(so, sa, auio, NULL, control, flags);
844 	if (error) {
845 		if (auio->uio_resid != len && (error == ERESTART ||
846 		    error == EINTR || error == EWOULDBLOCK))
847 			error = 0;
848 	}
849 #ifdef KTRACE
850 	if (ktriov != NULL) {
851 		if (error == 0) {
852 			ktruio.uio_iov = ktriov;
853 			ktruio.uio_resid = len - auio->uio_resid;
854 			ktrgenio(td->td_lwp, s, UIO_READ, &ktruio, error);
855 		}
856 		FREE(ktriov, M_TEMP);
857 	}
858 #endif
859 	if (error == 0)
860 		*res = len - auio->uio_resid;
861 done:
862 	fdrop(fp);
863 	return (error);
864 }
865 
866 /*
867  * recvfrom_args(int s, caddr_t buf, size_t len, int flags,
868  *			caddr_t from, int *fromlenaddr)
869  */
870 int
871 sys_recvfrom(struct recvfrom_args *uap)
872 {
873 	struct thread *td = curthread;
874 	struct uio auio;
875 	struct iovec aiov;
876 	struct sockaddr *sa = NULL;
877 	int error, fromlen;
878 
879 	if (uap->from && uap->fromlenaddr) {
880 		error = copyin(uap->fromlenaddr, &fromlen, sizeof(fromlen));
881 		if (error)
882 			return (error);
883 		if (fromlen < 0)
884 			return (EINVAL);
885 	} else {
886 		fromlen = 0;
887 	}
888 	aiov.iov_base = uap->buf;
889 	aiov.iov_len = uap->len;
890 	auio.uio_iov = &aiov;
891 	auio.uio_iovcnt = 1;
892 	auio.uio_offset = 0;
893 	auio.uio_resid = uap->len;
894 	auio.uio_segflg = UIO_USERSPACE;
895 	auio.uio_rw = UIO_READ;
896 	auio.uio_td = td;
897 
898 	error = kern_recvmsg(uap->s, uap->from ? &sa : NULL, &auio, NULL,
899 	    &uap->flags, &uap->sysmsg_result);
900 
901 	if (error == 0 && uap->from) {
902 		/* note: sa may still be NULL */
903 		if (sa) {
904 			fromlen = MIN(fromlen, sa->sa_len);
905 			error = copyout(sa, uap->from, fromlen);
906 		} else {
907 			fromlen = 0;
908 		}
909 		if (error == 0) {
910 			error = copyout(&fromlen, uap->fromlenaddr,
911 					sizeof(fromlen));
912 		}
913 	}
914 	if (sa)
915 		FREE(sa, M_SONAME);
916 
917 	return (error);
918 }
919 
920 /*
921  * recvmsg_args(int s, struct msghdr *msg, int flags)
922  */
923 int
924 sys_recvmsg(struct recvmsg_args *uap)
925 {
926 	struct thread *td = curthread;
927 	struct msghdr msg;
928 	struct uio auio;
929 	struct iovec aiov[UIO_SMALLIOV], *iov = NULL;
930 	struct mbuf *m, *control = NULL;
931 	struct sockaddr *sa = NULL;
932 	caddr_t ctlbuf;
933 	socklen_t *ufromlenp, *ucontrollenp;
934 	int error, fromlen, controllen, len, flags, *uflagsp;
935 
936 	/*
937 	 * This copyin handles everything except the iovec.
938 	 */
939 	error = copyin(uap->msg, &msg, sizeof(msg));
940 	if (error)
941 		return (error);
942 
943 	if (msg.msg_name && msg.msg_namelen < 0)
944 		return (EINVAL);
945 	if (msg.msg_control && msg.msg_controllen < 0)
946 		return (EINVAL);
947 
948 	ufromlenp = (socklen_t *)((caddr_t)uap->msg + offsetof(struct msghdr,
949 	    msg_namelen));
950 	ucontrollenp = (socklen_t *)((caddr_t)uap->msg + offsetof(struct msghdr,
951 	    msg_controllen));
952 	uflagsp = (int *)((caddr_t)uap->msg + offsetof(struct msghdr,
953 	    msg_flags));
954 
955 	/*
956 	 * Populate auio.
957 	 */
958 	error = iovec_copyin(msg.msg_iov, &iov, aiov, msg.msg_iovlen,
959 			     &auio.uio_resid);
960 	if (error)
961 		return (error);
962 	auio.uio_iov = iov;
963 	auio.uio_iovcnt = msg.msg_iovlen;
964 	auio.uio_offset = 0;
965 	auio.uio_segflg = UIO_USERSPACE;
966 	auio.uio_rw = UIO_READ;
967 	auio.uio_td = td;
968 
969 	flags = uap->flags;
970 
971 	error = kern_recvmsg(uap->s, msg.msg_name ? &sa : NULL, &auio,
972 	    msg.msg_control ? &control : NULL, &flags, &uap->sysmsg_result);
973 
974 	/*
975 	 * Conditionally copyout the name and populate the namelen field.
976 	 */
977 	if (error == 0 && msg.msg_name) {
978 		/* note: sa may still be NULL */
979 		if (sa != NULL) {
980 			fromlen = MIN(msg.msg_namelen, sa->sa_len);
981 			error = copyout(sa, msg.msg_name, fromlen);
982 		} else {
983 			fromlen = 0;
984 		}
985 		if (error == 0)
986 			error = copyout(&fromlen, ufromlenp,
987 			    sizeof(*ufromlenp));
988 	}
989 
990 	/*
991 	 * Copyout msg.msg_control and msg.msg_controllen.
992 	 */
993 	if (error == 0 && msg.msg_control) {
994 		len = msg.msg_controllen;
995 		m = control;
996 		ctlbuf = (caddr_t)msg.msg_control;
997 
998 		while(m && len > 0) {
999 			unsigned int tocopy;
1000 
1001 			if (len >= m->m_len) {
1002 				tocopy = m->m_len;
1003 			} else {
1004 				msg.msg_flags |= MSG_CTRUNC;
1005 				tocopy = len;
1006 			}
1007 
1008 			error = copyout(mtod(m, caddr_t), ctlbuf, tocopy);
1009 			if (error)
1010 				goto cleanup;
1011 
1012 			ctlbuf += tocopy;
1013 			len -= tocopy;
1014 			m = m->m_next;
1015 		}
1016 		controllen = ctlbuf - (caddr_t)msg.msg_control;
1017 		error = copyout(&controllen, ucontrollenp,
1018 		    sizeof(*ucontrollenp));
1019 	}
1020 
1021 	if (error == 0)
1022 		error = copyout(&flags, uflagsp, sizeof(*uflagsp));
1023 
1024 cleanup:
1025 	if (sa)
1026 		FREE(sa, M_SONAME);
1027 	iovec_free(&iov, aiov);
1028 	if (control)
1029 		m_freem(control);
1030 	return (error);
1031 }
1032 
1033 /*
1034  * If sopt->sopt_td == NULL, then sopt->sopt_val is treated as an
1035  * in kernel pointer instead of a userland pointer.  This allows us
1036  * to manipulate socket options in the emulation code.
1037  */
1038 int
1039 kern_setsockopt(int s, struct sockopt *sopt)
1040 {
1041 	struct thread *td = curthread;
1042 	struct proc *p = td->td_proc;
1043 	struct file *fp;
1044 	int error;
1045 
1046 	if (sopt->sopt_val == NULL && sopt->sopt_valsize != 0)
1047 		return (EFAULT);
1048 	if (sopt->sopt_valsize < 0)
1049 		return (EINVAL);
1050 
1051 	error = holdsock(p->p_fd, s, &fp);
1052 	if (error)
1053 		return (error);
1054 
1055 	error = sosetopt((struct socket *)fp->f_data, sopt);
1056 	fdrop(fp);
1057 	return (error);
1058 }
1059 
1060 /*
1061  * setsockopt_args(int s, int level, int name, caddr_t val, int valsize)
1062  */
1063 int
1064 sys_setsockopt(struct setsockopt_args *uap)
1065 {
1066 	struct thread *td = curthread;
1067 	struct sockopt sopt;
1068 	int error;
1069 
1070 	sopt.sopt_level = uap->level;
1071 	sopt.sopt_name = uap->name;
1072 	sopt.sopt_valsize = uap->valsize;
1073 	sopt.sopt_td = td;
1074 	sopt.sopt_val = NULL;
1075 
1076 	if (sopt.sopt_valsize < 0 || sopt.sopt_valsize > SOMAXOPT_SIZE)
1077 		return (EINVAL);
1078 	if (uap->val) {
1079 		sopt.sopt_val = kmalloc(sopt.sopt_valsize, M_TEMP, M_WAITOK);
1080 		error = copyin(uap->val, sopt.sopt_val, sopt.sopt_valsize);
1081 		if (error)
1082 			goto out;
1083 	}
1084 
1085 	error = kern_setsockopt(uap->s, &sopt);
1086 out:
1087 	if (uap->val)
1088 		kfree(sopt.sopt_val, M_TEMP);
1089 	return(error);
1090 }
1091 
1092 /*
1093  * If sopt->sopt_td == NULL, then sopt->sopt_val is treated as an
1094  * in kernel pointer instead of a userland pointer.  This allows us
1095  * to manipulate socket options in the emulation code.
1096  */
1097 int
1098 kern_getsockopt(int s, struct sockopt *sopt)
1099 {
1100 	struct thread *td = curthread;
1101 	struct proc *p = td->td_proc;
1102 	struct file *fp;
1103 	int error;
1104 
1105 	if (sopt->sopt_val == NULL && sopt->sopt_valsize != 0)
1106 		return (EFAULT);
1107 	if (sopt->sopt_valsize < 0 || sopt->sopt_valsize > SOMAXOPT_SIZE)
1108 		return (EINVAL);
1109 
1110 	error = holdsock(p->p_fd, s, &fp);
1111 	if (error)
1112 		return (error);
1113 
1114 	error = sogetopt((struct socket *)fp->f_data, sopt);
1115 	fdrop(fp);
1116 	return (error);
1117 }
1118 
1119 /*
1120  * getsockopt_Args(int s, int level, int name, caddr_t val, int *avalsize)
1121  */
1122 int
1123 sys_getsockopt(struct getsockopt_args *uap)
1124 {
1125 	struct thread *td = curthread;
1126 	struct	sockopt sopt;
1127 	int	error, valsize;
1128 
1129 	if (uap->val) {
1130 		error = copyin(uap->avalsize, &valsize, sizeof(valsize));
1131 		if (error)
1132 			return (error);
1133 	} else {
1134 		valsize = 0;
1135 	}
1136 
1137 	sopt.sopt_level = uap->level;
1138 	sopt.sopt_name = uap->name;
1139 	sopt.sopt_valsize = valsize;
1140 	sopt.sopt_td = td;
1141 	sopt.sopt_val = NULL;
1142 
1143 	if (sopt.sopt_valsize < 0 || sopt.sopt_valsize > SOMAXOPT_SIZE)
1144 		return (EINVAL);
1145 	if (uap->val) {
1146 		sopt.sopt_val = kmalloc(sopt.sopt_valsize, M_TEMP, M_WAITOK);
1147 		error = copyin(uap->val, sopt.sopt_val, sopt.sopt_valsize);
1148 		if (error)
1149 			goto out;
1150 	}
1151 
1152 	error = kern_getsockopt(uap->s, &sopt);
1153 	if (error)
1154 		goto out;
1155 	valsize = sopt.sopt_valsize;
1156 	error = copyout(&valsize, uap->avalsize, sizeof(valsize));
1157 	if (error)
1158 		goto out;
1159 	if (uap->val)
1160 		error = copyout(sopt.sopt_val, uap->val, sopt.sopt_valsize);
1161 out:
1162 	if (uap->val)
1163 		kfree(sopt.sopt_val, M_TEMP);
1164 	return (error);
1165 }
1166 
1167 /*
1168  * The second argument to kern_getsockname() is a handle to a struct sockaddr.
1169  * This allows kern_getsockname() to return a pointer to an allocated struct
1170  * sockaddr which must be freed later with FREE().  The caller must
1171  * initialize *name to NULL.
1172  */
1173 int
1174 kern_getsockname(int s, struct sockaddr **name, int *namelen)
1175 {
1176 	struct thread *td = curthread;
1177 	struct proc *p = td->td_proc;
1178 	struct file *fp;
1179 	struct socket *so;
1180 	struct sockaddr *sa = NULL;
1181 	int error;
1182 
1183 	error = holdsock(p->p_fd, s, &fp);
1184 	if (error)
1185 		return (error);
1186 	if (*namelen < 0) {
1187 		fdrop(fp);
1188 		return (EINVAL);
1189 	}
1190 	so = (struct socket *)fp->f_data;
1191 	error = so_pru_sockaddr(so, &sa);
1192 	if (error == 0) {
1193 		if (sa == NULL) {
1194 			*namelen = 0;
1195 		} else {
1196 			*namelen = MIN(*namelen, sa->sa_len);
1197 			*name = sa;
1198 		}
1199 	}
1200 
1201 	fdrop(fp);
1202 	return (error);
1203 }
1204 
1205 /*
1206  * getsockname_args(int fdes, caddr_t asa, int *alen)
1207  *
1208  * Get socket name.
1209  */
1210 int
1211 sys_getsockname(struct getsockname_args *uap)
1212 {
1213 	struct sockaddr *sa = NULL;
1214 	int error, sa_len;
1215 
1216 	error = copyin(uap->alen, &sa_len, sizeof(sa_len));
1217 	if (error)
1218 		return (error);
1219 
1220 	error = kern_getsockname(uap->fdes, &sa, &sa_len);
1221 
1222 	if (error == 0)
1223 		error = copyout(sa, uap->asa, sa_len);
1224 	if (error == 0)
1225 		error = copyout(&sa_len, uap->alen, sizeof(*uap->alen));
1226 	if (sa)
1227 		FREE(sa, M_SONAME);
1228 	return (error);
1229 }
1230 
1231 /*
1232  * The second argument to kern_getpeername() is a handle to a struct sockaddr.
1233  * This allows kern_getpeername() to return a pointer to an allocated struct
1234  * sockaddr which must be freed later with FREE().  The caller must
1235  * initialize *name to NULL.
1236  */
1237 int
1238 kern_getpeername(int s, struct sockaddr **name, int *namelen)
1239 {
1240 	struct thread *td = curthread;
1241 	struct proc *p = td->td_proc;
1242 	struct file *fp;
1243 	struct socket *so;
1244 	struct sockaddr *sa = NULL;
1245 	int error;
1246 
1247 	error = holdsock(p->p_fd, s, &fp);
1248 	if (error)
1249 		return (error);
1250 	if (*namelen < 0) {
1251 		fdrop(fp);
1252 		return (EINVAL);
1253 	}
1254 	so = (struct socket *)fp->f_data;
1255 	if ((so->so_state & (SS_ISCONNECTED|SS_ISCONFIRMING)) == 0) {
1256 		fdrop(fp);
1257 		return (ENOTCONN);
1258 	}
1259 	error = so_pru_peeraddr(so, &sa);
1260 	if (error == 0) {
1261 		if (sa == NULL) {
1262 			*namelen = 0;
1263 		} else {
1264 			*namelen = MIN(*namelen, sa->sa_len);
1265 			*name = sa;
1266 		}
1267 	}
1268 
1269 	fdrop(fp);
1270 	return (error);
1271 }
1272 
1273 /*
1274  * getpeername_args(int fdes, caddr_t asa, int *alen)
1275  *
1276  * Get name of peer for connected socket.
1277  */
1278 int
1279 sys_getpeername(struct getpeername_args *uap)
1280 {
1281 	struct sockaddr *sa = NULL;
1282 	int error, sa_len;
1283 
1284 	error = copyin(uap->alen, &sa_len, sizeof(sa_len));
1285 	if (error)
1286 		return (error);
1287 
1288 	error = kern_getpeername(uap->fdes, &sa, &sa_len);
1289 
1290 	if (error == 0)
1291 		error = copyout(sa, uap->asa, sa_len);
1292 	if (error == 0)
1293 		error = copyout(&sa_len, uap->alen, sizeof(*uap->alen));
1294 	if (sa)
1295 		FREE(sa, M_SONAME);
1296 	return (error);
1297 }
1298 
1299 int
1300 getsockaddr(struct sockaddr **namp, caddr_t uaddr, size_t len)
1301 {
1302 	struct sockaddr *sa;
1303 	int error;
1304 
1305 	*namp = NULL;
1306 	if (len > SOCK_MAXADDRLEN)
1307 		return ENAMETOOLONG;
1308 	if (len < offsetof(struct sockaddr, sa_data[0]))
1309 		return EDOM;
1310 	MALLOC(sa, struct sockaddr *, len, M_SONAME, M_WAITOK);
1311 	error = copyin(uaddr, sa, len);
1312 	if (error) {
1313 		FREE(sa, M_SONAME);
1314 	} else {
1315 #if BYTE_ORDER != BIG_ENDIAN
1316 		/*
1317 		 * The bind(), connect(), and sendto() syscalls were not
1318 		 * versioned for COMPAT_43.  Thus, this check must stay.
1319 		 */
1320 		if (sa->sa_family == 0 && sa->sa_len < AF_MAX)
1321 			sa->sa_family = sa->sa_len;
1322 #endif
1323 		sa->sa_len = len;
1324 		*namp = sa;
1325 	}
1326 	return error;
1327 }
1328 
1329 /*
1330  * Detach a mapped page and release resources back to the system.
1331  * We must release our wiring and if the object is ripped out
1332  * from under the vm_page we become responsible for freeing the
1333  * page.  These routines must be MPSAFE.
1334  *
1335  * XXX HACK XXX TEMPORARY UNTIL WE IMPLEMENT EXT MBUF REFERENCE COUNTING
1336  *
1337  * XXX vm_page_*() routines are not MPSAFE yet, the MP lock is required.
1338  */
1339 static void
1340 sf_buf_mref(void *arg)
1341 {
1342 	struct sfbuf_mref *sfm = arg;
1343 
1344 	/*
1345 	 * We must already hold a ref so there is no race to 0, just
1346 	 * atomically increment the count.
1347 	 */
1348 	atomic_add_int(&sfm->mref_count, 1);
1349 }
1350 
1351 static void
1352 sf_buf_mfree(void *arg)
1353 {
1354 	struct sfbuf_mref *sfm = arg;
1355 	vm_page_t m;
1356 
1357 	KKASSERT(sfm->mref_count > 0);
1358 	if (atomic_fetchadd_int(&sfm->mref_count, -1) == 1) {
1359 		/*
1360 		 * XXX vm_page_*() and SFBUF routines not MPSAFE yet.
1361 		 */
1362 		get_mplock();
1363 		crit_enter();
1364 		m = sf_buf_page(sfm->sf);
1365 		sf_buf_free(sfm->sf);
1366 		vm_page_unwire(m, 0);
1367 		if (m->wire_count == 0 && m->object == NULL)
1368 			vm_page_try_to_free(m);
1369 		crit_exit();
1370 		rel_mplock();
1371 		kfree(sfm, M_SENDFILE);
1372 	}
1373 }
1374 
1375 /*
1376  * sendfile(2).
1377  * int sendfile(int fd, int s, off_t offset, size_t nbytes,
1378  *	 struct sf_hdtr *hdtr, off_t *sbytes, int flags)
1379  *
1380  * Send a file specified by 'fd' and starting at 'offset' to a socket
1381  * specified by 's'. Send only 'nbytes' of the file or until EOF if
1382  * nbytes == 0. Optionally add a header and/or trailer to the socket
1383  * output. If specified, write the total number of bytes sent into *sbytes.
1384  *
1385  * In FreeBSD kern/uipc_syscalls.c,v 1.103, a bug was fixed that caused
1386  * the headers to count against the remaining bytes to be sent from
1387  * the file descriptor.  We may wish to implement a compatibility syscall
1388  * in the future.
1389  */
1390 int
1391 sys_sendfile(struct sendfile_args *uap)
1392 {
1393 	struct thread *td = curthread;
1394 	struct proc *p = td->td_proc;
1395 	struct file *fp;
1396 	struct vnode *vp = NULL;
1397 	struct sf_hdtr hdtr;
1398 	struct iovec aiov[UIO_SMALLIOV], *iov = NULL;
1399 	struct uio auio;
1400 	struct mbuf *mheader = NULL;
1401 	off_t hdtr_size = 0, sbytes;
1402 	int error, hbytes = 0, tbytes;
1403 
1404 	KKASSERT(p);
1405 
1406 	/*
1407 	 * Do argument checking. Must be a regular file in, stream
1408 	 * type and connected socket out, positive offset.
1409 	 */
1410 	fp = holdfp(p->p_fd, uap->fd, FREAD);
1411 	if (fp == NULL) {
1412 		return (EBADF);
1413 	}
1414 	if (fp->f_type != DTYPE_VNODE) {
1415 		fdrop(fp);
1416 		return (EINVAL);
1417 	}
1418 	vp = (struct vnode *)fp->f_data;
1419 	vref(vp);
1420 	fdrop(fp);
1421 
1422 	/*
1423 	 * If specified, get the pointer to the sf_hdtr struct for
1424 	 * any headers/trailers.
1425 	 */
1426 	if (uap->hdtr) {
1427 		error = copyin(uap->hdtr, &hdtr, sizeof(hdtr));
1428 		if (error)
1429 			goto done;
1430 		/*
1431 		 * Send any headers.
1432 		 */
1433 		if (hdtr.headers) {
1434 			error = iovec_copyin(hdtr.headers, &iov, aiov,
1435 					     hdtr.hdr_cnt, &hbytes);
1436 			if (error)
1437 				goto done;
1438 			auio.uio_iov = iov;
1439 			auio.uio_iovcnt = hdtr.hdr_cnt;
1440 			auio.uio_offset = 0;
1441 			auio.uio_segflg = UIO_USERSPACE;
1442 			auio.uio_rw = UIO_WRITE;
1443 			auio.uio_td = td;
1444 			auio.uio_resid = hbytes;
1445 
1446 			mheader = m_uiomove(&auio);
1447 
1448 			iovec_free(&iov, aiov);
1449 			if (mheader == NULL)
1450 				goto done;
1451 		}
1452 	}
1453 
1454 	error = kern_sendfile(vp, uap->s, uap->offset, uap->nbytes, mheader,
1455 	    &sbytes, uap->flags);
1456 	if (error)
1457 		goto done;
1458 
1459 	/*
1460 	 * Send trailers. Wimp out and use writev(2).
1461 	 */
1462 	if (uap->hdtr != NULL && hdtr.trailers != NULL) {
1463 		error = iovec_copyin(hdtr.trailers, &iov, aiov,
1464 				     hdtr.trl_cnt, &auio.uio_resid);
1465 		if (error)
1466 			goto done;
1467 		auio.uio_iov = iov;
1468 		auio.uio_iovcnt = hdtr.trl_cnt;
1469 		auio.uio_offset = 0;
1470 		auio.uio_segflg = UIO_USERSPACE;
1471 		auio.uio_rw = UIO_WRITE;
1472 		auio.uio_td = td;
1473 
1474 		error = kern_sendmsg(uap->s, NULL, &auio, NULL, 0, &tbytes);
1475 
1476 		iovec_free(&iov, aiov);
1477 		if (error)
1478 			goto done;
1479 		hdtr_size += tbytes;	/* trailer bytes successfully sent */
1480 	}
1481 
1482 done:
1483 	if (uap->sbytes != NULL) {
1484 		sbytes += hdtr_size;
1485 		copyout(&sbytes, uap->sbytes, sizeof(off_t));
1486 	}
1487 	if (vp)
1488 		vrele(vp);
1489 	return (error);
1490 }
1491 
1492 int
1493 kern_sendfile(struct vnode *vp, int sfd, off_t offset, size_t nbytes,
1494     struct mbuf *mheader, off_t *sbytes, int flags)
1495 {
1496 	struct thread *td = curthread;
1497 	struct proc *p = td->td_proc;
1498 	struct vm_object *obj;
1499 	struct socket *so;
1500 	struct file *fp;
1501 	struct mbuf *m;
1502 	struct sf_buf *sf;
1503 	struct sfbuf_mref *sfm;
1504 	struct vm_page *pg;
1505 	off_t off, xfsize;
1506 	off_t hbytes = 0;
1507 	int error = 0;
1508 
1509 	if (vp->v_type != VREG) {
1510 		error = EINVAL;
1511 		goto done0;
1512 	}
1513 	if ((obj = vp->v_object) == NULL) {
1514 		error = EINVAL;
1515 		goto done0;
1516 	}
1517 	error = holdsock(p->p_fd, sfd, &fp);
1518 	if (error)
1519 		goto done0;
1520 	so = (struct socket *)fp->f_data;
1521 	if (so->so_type != SOCK_STREAM) {
1522 		error = EINVAL;
1523 		goto done;
1524 	}
1525 	if ((so->so_state & SS_ISCONNECTED) == 0) {
1526 		error = ENOTCONN;
1527 		goto done;
1528 	}
1529 	if (offset < 0) {
1530 		error = EINVAL;
1531 		goto done;
1532 	}
1533 
1534 	*sbytes = 0;
1535 	/*
1536 	 * Protect against multiple writers to the socket.
1537 	 */
1538 	ssb_lock(&so->so_snd, M_WAITOK);
1539 
1540 	/*
1541 	 * Loop through the pages in the file, starting with the requested
1542 	 * offset. Get a file page (do I/O if necessary), map the file page
1543 	 * into an sf_buf, attach an mbuf header to the sf_buf, and queue
1544 	 * it on the socket.
1545 	 */
1546 	for (off = offset; ; off += xfsize, *sbytes += xfsize + hbytes) {
1547 		vm_pindex_t pindex;
1548 		vm_offset_t pgoff;
1549 
1550 		pindex = OFF_TO_IDX(off);
1551 retry_lookup:
1552 		/*
1553 		 * Calculate the amount to transfer. Not to exceed a page,
1554 		 * the EOF, or the passed in nbytes.
1555 		 */
1556 		xfsize = vp->v_filesize - off;
1557 		if (xfsize > PAGE_SIZE)
1558 			xfsize = PAGE_SIZE;
1559 		pgoff = (vm_offset_t)(off & PAGE_MASK);
1560 		if (PAGE_SIZE - pgoff < xfsize)
1561 			xfsize = PAGE_SIZE - pgoff;
1562 		if (nbytes && xfsize > (nbytes - *sbytes))
1563 			xfsize = nbytes - *sbytes;
1564 		if (xfsize <= 0)
1565 			break;
1566 		/*
1567 		 * Optimize the non-blocking case by looking at the socket space
1568 		 * before going to the extra work of constituting the sf_buf.
1569 		 */
1570 		if ((fp->f_flag & FNONBLOCK) && ssb_space(&so->so_snd) <= 0) {
1571 			if (so->so_state & SS_CANTSENDMORE)
1572 				error = EPIPE;
1573 			else
1574 				error = EAGAIN;
1575 			ssb_unlock(&so->so_snd);
1576 			goto done;
1577 		}
1578 		/*
1579 		 * Attempt to look up the page.
1580 		 *
1581 		 *	Allocate if not found, wait and loop if busy, then
1582 		 *	wire the page.  critical section protection is
1583 		 * 	required to maintain the object association (an
1584 		 *	interrupt can free the page) through to the
1585 		 *	vm_page_wire() call.
1586 		 */
1587 		crit_enter();
1588 		pg = vm_page_lookup(obj, pindex);
1589 		if (pg == NULL) {
1590 			pg = vm_page_alloc(obj, pindex, VM_ALLOC_NORMAL);
1591 			if (pg == NULL) {
1592 				vm_wait(0);
1593 				crit_exit();
1594 				goto retry_lookup;
1595 			}
1596 			vm_page_wakeup(pg);
1597 		} else if (vm_page_sleep_busy(pg, TRUE, "sfpbsy")) {
1598 			crit_exit();
1599 			goto retry_lookup;
1600 		}
1601 		vm_page_wire(pg);
1602 		crit_exit();
1603 
1604 		/*
1605 		 * If page is not valid for what we need, initiate I/O
1606 		 */
1607 
1608 		if (!pg->valid || !vm_page_is_valid(pg, pgoff, xfsize)) {
1609 			struct uio auio;
1610 			struct iovec aiov;
1611 			int bsize;
1612 
1613 			/*
1614 			 * Ensure that our page is still around when the I/O
1615 			 * completes.
1616 			 */
1617 			vm_page_io_start(pg);
1618 
1619 			/*
1620 			 * Get the page from backing store.
1621 			 */
1622 			bsize = vp->v_mount->mnt_stat.f_iosize;
1623 			auio.uio_iov = &aiov;
1624 			auio.uio_iovcnt = 1;
1625 			aiov.iov_base = 0;
1626 			aiov.iov_len = MAXBSIZE;
1627 			auio.uio_resid = MAXBSIZE;
1628 			auio.uio_offset = trunc_page(off);
1629 			auio.uio_segflg = UIO_NOCOPY;
1630 			auio.uio_rw = UIO_READ;
1631 			auio.uio_td = td;
1632 			vn_lock(vp, LK_SHARED | LK_RETRY);
1633 			error = VOP_READ(vp, &auio,
1634 				    IO_VMIO | ((MAXBSIZE / bsize) << 16),
1635 				    p->p_ucred);
1636 			vn_unlock(vp);
1637 			vm_page_flag_clear(pg, PG_ZERO);
1638 			vm_page_io_finish(pg);
1639 			if (error) {
1640 				crit_enter();
1641 				vm_page_unwire(pg, 0);
1642 				vm_page_try_to_free(pg);
1643 				crit_exit();
1644 				ssb_unlock(&so->so_snd);
1645 				goto done;
1646 			}
1647 		}
1648 
1649 
1650 		/*
1651 		 * Get a sendfile buf. We usually wait as long as necessary,
1652 		 * but this wait can be interrupted.
1653 		 */
1654 		if ((sf = sf_buf_alloc(pg, SFB_CATCH)) == NULL) {
1655 			crit_enter();
1656 			vm_page_unwire(pg, 0);
1657 			vm_page_try_to_free(pg);
1658 			crit_exit();
1659 			ssb_unlock(&so->so_snd);
1660 			error = EINTR;
1661 			goto done;
1662 		}
1663 
1664 		/*
1665 		 * Get an mbuf header and set it up as having external storage.
1666 		 */
1667 		MGETHDR(m, MB_WAIT, MT_DATA);
1668 		if (m == NULL) {
1669 			error = ENOBUFS;
1670 			sf_buf_free(sf);
1671 			ssb_unlock(&so->so_snd);
1672 			goto done;
1673 		}
1674 
1675 		/*
1676 		 * sfm is a temporary hack, use a per-cpu cache for this.
1677 		 */
1678 		sfm = kmalloc(sizeof(struct sfbuf_mref), M_SENDFILE, M_WAITOK);
1679 		sfm->sf = sf;
1680 		sfm->mref_count = 1;
1681 
1682 		m->m_ext.ext_free = sf_buf_mfree;
1683 		m->m_ext.ext_ref = sf_buf_mref;
1684 		m->m_ext.ext_arg = sfm;
1685 		m->m_ext.ext_buf = (void *)sf->kva;
1686 		m->m_ext.ext_size = PAGE_SIZE;
1687 		m->m_data = (char *) sf->kva + pgoff;
1688 		m->m_flags |= M_EXT;
1689 		m->m_pkthdr.len = m->m_len = xfsize;
1690 		KKASSERT((m->m_flags & (M_EXT_CLUSTER)) == 0);
1691 
1692 		if (mheader != NULL) {
1693 			hbytes = mheader->m_pkthdr.len;
1694 			mheader->m_pkthdr.len += m->m_pkthdr.len;
1695 			m_cat(mheader, m);
1696 			m = mheader;
1697 			mheader = NULL;
1698 		} else
1699 			hbytes = 0;
1700 
1701 		/*
1702 		 * Add the buffer to the socket buffer chain.
1703 		 */
1704 		crit_enter();
1705 retry_space:
1706 		/*
1707 		 * Make sure that the socket is still able to take more data.
1708 		 * CANTSENDMORE being true usually means that the connection
1709 		 * was closed. so_error is true when an error was sensed after
1710 		 * a previous send.
1711 		 * The state is checked after the page mapping and buffer
1712 		 * allocation above since those operations may block and make
1713 		 * any socket checks stale. From this point forward, nothing
1714 		 * blocks before the pru_send (or more accurately, any blocking
1715 		 * results in a loop back to here to re-check).
1716 		 */
1717 		if ((so->so_state & SS_CANTSENDMORE) || so->so_error) {
1718 			if (so->so_state & SS_CANTSENDMORE) {
1719 				error = EPIPE;
1720 			} else {
1721 				error = so->so_error;
1722 				so->so_error = 0;
1723 			}
1724 			m_freem(m);
1725 			ssb_unlock(&so->so_snd);
1726 			crit_exit();
1727 			goto done;
1728 		}
1729 		/*
1730 		 * Wait for socket space to become available. We do this just
1731 		 * after checking the connection state above in order to avoid
1732 		 * a race condition with ssb_wait().
1733 		 */
1734 		if (ssb_space(&so->so_snd) < so->so_snd.ssb_lowat) {
1735 			if (fp->f_flag & FNONBLOCK) {
1736 				m_freem(m);
1737 				ssb_unlock(&so->so_snd);
1738 				crit_exit();
1739 				error = EAGAIN;
1740 				goto done;
1741 			}
1742 			error = ssb_wait(&so->so_snd);
1743 			/*
1744 			 * An error from ssb_wait usually indicates that we've
1745 			 * been interrupted by a signal. If we've sent anything
1746 			 * then return bytes sent, otherwise return the error.
1747 			 */
1748 			if (error) {
1749 				m_freem(m);
1750 				ssb_unlock(&so->so_snd);
1751 				crit_exit();
1752 				goto done;
1753 			}
1754 			goto retry_space;
1755 		}
1756 		error = so_pru_send(so, 0, m, NULL, NULL, td);
1757 		crit_exit();
1758 		if (error) {
1759 			ssb_unlock(&so->so_snd);
1760 			goto done;
1761 		}
1762 	}
1763 	if (mheader != NULL) {
1764 		*sbytes += mheader->m_pkthdr.len;
1765 		error = so_pru_send(so, 0, mheader, NULL, NULL, td);
1766 		mheader = NULL;
1767 	}
1768 	ssb_unlock(&so->so_snd);
1769 
1770 done:
1771 	fdrop(fp);
1772 done0:
1773 	if (mheader != NULL)
1774 		m_freem(mheader);
1775 	return (error);
1776 }
1777 
1778 int
1779 sys_sctp_peeloff(struct sctp_peeloff_args *uap)
1780 {
1781 #ifdef SCTP
1782 	struct thread *td = curthread;
1783 	struct proc *p = td->td_proc;
1784 	struct file *lfp = NULL;
1785 	struct file *nfp = NULL;
1786 	int error;
1787 	struct socket *head, *so;
1788 	caddr_t assoc_id;
1789 	int fd;
1790 	short fflag;		/* type must match fp->f_flag */
1791 
1792 	assoc_id = uap->name;
1793 	error = holdsock(p->p_fd, uap->sd, &lfp);
1794 	if (error) {
1795 		return (error);
1796 	}
1797 	crit_enter();
1798 	head = (struct socket *)lfp->f_data;
1799 	error = sctp_can_peel_off(head, assoc_id);
1800 	if (error) {
1801 		crit_exit();
1802 		goto done;
1803 	}
1804 	/*
1805 	 * At this point we know we do have a assoc to pull
1806 	 * we proceed to get the fd setup. This may block
1807 	 * but that is ok.
1808 	 */
1809 
1810 	fflag = lfp->f_flag;
1811 	error = falloc(p, &nfp, &fd);
1812 	if (error) {
1813 		/*
1814 		 * Probably ran out of file descriptors. Put the
1815 		 * unaccepted connection back onto the queue and
1816 		 * do another wakeup so some other process might
1817 		 * have a chance at it.
1818 		 */
1819 		crit_exit();
1820 		goto done;
1821 	}
1822 	uap->sysmsg_result = fd;
1823 
1824 	so = sctp_get_peeloff(head, assoc_id, &error);
1825 	if (so == NULL) {
1826 		/*
1827 		 * Either someone else peeled it off OR
1828 		 * we can't get a socket.
1829 		 */
1830 		goto noconnection;
1831 	}
1832 	so->so_state &= ~SS_COMP;
1833 	so->so_state &= ~SS_NOFDREF;
1834 	so->so_head = NULL;
1835 	if (head->so_sigio != NULL)
1836 		fsetown(fgetown(head->so_sigio), &so->so_sigio);
1837 
1838 	nfp->f_type = DTYPE_SOCKET;
1839 	nfp->f_flag = fflag;
1840 	nfp->f_ops = &socketops;
1841 	nfp->f_data = so;
1842 
1843 noconnection:
1844 	/*
1845 	 * Assign the file pointer to the reserved descriptor, or clear
1846 	 * the reserved descriptor if an error occured.
1847 	 */
1848 	if (error)
1849 		fsetfd(p, NULL, fd);
1850 	else
1851 		fsetfd(p, nfp, fd);
1852 	crit_exit();
1853 	/*
1854 	 * Release explicitly held references before returning.
1855 	 */
1856 done:
1857 	if (nfp != NULL)
1858 		fdrop(nfp);
1859 	fdrop(lfp);
1860 	return (error);
1861 #else /* SCTP */
1862 	return(EOPNOTSUPP);
1863 #endif /* SCTP */
1864 }
1865