xref: /illumos-gate/usr/src/uts/common/fs/sockfs/socksyscalls.c (revision 2aeafac3612e19716bf8164f89c3c9196342979c)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 
22 /*
23  * Copyright (c) 1995, 2010, Oracle and/or its affiliates. All rights reserved.
24  * Copyright 2015, Joyent, Inc.  All rights reserved.
25  * Copyright (c) 2013, OmniTI Computer Consulting, Inc. All rights reserved.
26  * Copyright 2015 Nexenta Systems, Inc. All rights reserved.
27  */
28 
29 #include <sys/types.h>
30 #include <sys/t_lock.h>
31 #include <sys/param.h>
32 #include <sys/systm.h>
33 #include <sys/buf.h>
34 #include <sys/conf.h>
35 #include <sys/cred.h>
36 #include <sys/kmem.h>
37 #include <sys/sysmacros.h>
38 #include <sys/vfs.h>
39 #include <sys/vnode.h>
40 #include <sys/debug.h>
41 #include <sys/errno.h>
42 #include <sys/time.h>
43 #include <sys/file.h>
44 #include <sys/user.h>
45 #include <sys/stream.h>
46 #include <sys/strsubr.h>
47 #include <sys/strsun.h>
48 #include <sys/sunddi.h>
49 #include <sys/esunddi.h>
50 #include <sys/flock.h>
51 #include <sys/modctl.h>
52 #include <sys/cmn_err.h>
53 #include <sys/vmsystm.h>
54 #include <sys/policy.h>
55 #include <sys/limits.h>
56 
57 #include <sys/socket.h>
58 #include <sys/socketvar.h>
59 
60 #include <sys/isa_defs.h>
61 #include <sys/inttypes.h>
62 #include <sys/systm.h>
63 #include <sys/cpuvar.h>
64 #include <sys/filio.h>
65 #include <sys/sendfile.h>
66 #include <sys/ddi.h>
67 #include <vm/seg.h>
68 #include <vm/seg_map.h>
69 #include <vm/seg_kpm.h>
70 
71 #include <fs/sockfs/nl7c.h>
72 #include <fs/sockfs/sockcommon.h>
73 #include <fs/sockfs/sockfilter_impl.h>
74 #include <fs/sockfs/socktpi.h>
75 
76 #ifdef SOCK_TEST
77 int do_useracc = 1;		/* Controlled by setting SO_DEBUG to 4 */
78 #else
79 #define	do_useracc	1
80 #endif /* SOCK_TEST */
81 
82 extern int	xnet_truncate_print;
83 
84 extern void	nl7c_init(void);
85 extern int	sockfs_defer_nl7c_init;
86 
87 /*
88  * Kernel component of socket creation.
89  *
90  * The socket library determines which version number to use.
91  * First the library calls this with a NULL devpath. If this fails
92  * to find a transport (using solookup) the library will look in /etc/netconfig
93  * for the appropriate transport. If one is found it will pass in the
94  * devpath for the kernel to use.
95  */
96 int
97 so_socket(int family, int type_w_flags, int protocol, char *devpath,
98     int version)
99 {
100 	struct sonode *so;
101 	vnode_t *vp;
102 	struct file *fp;
103 	int fd;
104 	int error;
105 	int type;
106 
107 	type = type_w_flags & SOCK_TYPE_MASK;
108 	type_w_flags &= ~SOCK_TYPE_MASK;
109 	if (type_w_flags & ~(SOCK_CLOEXEC|SOCK_NDELAY|SOCK_NONBLOCK))
110 		return (set_errno(EINVAL));
111 
112 	if (devpath != NULL) {
113 		char *buf;
114 		size_t kdevpathlen = 0;
115 
116 		buf = kmem_alloc(MAXPATHLEN, KM_SLEEP);
117 		if ((error = copyinstr(devpath, buf,
118 		    MAXPATHLEN, &kdevpathlen)) != 0) {
119 			kmem_free(buf, MAXPATHLEN);
120 			return (set_errno(error));
121 		}
122 		so = socket_create(family, type, protocol, buf, NULL,
123 		    SOCKET_SLEEP, version, CRED(), &error);
124 		kmem_free(buf, MAXPATHLEN);
125 	} else {
126 		so = socket_create(family, type, protocol, NULL, NULL,
127 		    SOCKET_SLEEP, version, CRED(), &error);
128 	}
129 	if (so == NULL)
130 		return (set_errno(error));
131 
132 	/* Allocate a file descriptor for the socket */
133 	vp = SOTOV(so);
134 	if (error = falloc(vp, FWRITE|FREAD, &fp, &fd)) {
135 		(void) socket_close(so, 0, CRED());
136 		socket_destroy(so);
137 		return (set_errno(error));
138 	}
139 
140 	/*
141 	 * Now fill in the entries that falloc reserved
142 	 */
143 	if (type_w_flags & SOCK_NDELAY) {
144 		so->so_state |= SS_NDELAY;
145 		fp->f_flag |= FNDELAY;
146 	}
147 	if (type_w_flags & SOCK_NONBLOCK) {
148 		so->so_state |= SS_NONBLOCK;
149 		fp->f_flag |= FNONBLOCK;
150 	}
151 	mutex_exit(&fp->f_tlock);
152 	setf(fd, fp);
153 	if ((type_w_flags & SOCK_CLOEXEC) != 0) {
154 		f_setfd(fd, FD_CLOEXEC);
155 	}
156 
157 	return (fd);
158 }
159 
160 /*
161  * Map from a file descriptor to a socket node.
162  * Returns with the file descriptor held i.e. the caller has to
163  * use releasef when done with the file descriptor.
164  */
165 struct sonode *
166 getsonode(int sock, int *errorp, file_t **fpp)
167 {
168 	file_t *fp;
169 	vnode_t *vp;
170 	struct sonode *so;
171 
172 	if ((fp = getf(sock)) == NULL) {
173 		*errorp = EBADF;
174 		eprintline(*errorp);
175 		return (NULL);
176 	}
177 	vp = fp->f_vnode;
178 	/* Check if it is a socket */
179 	if (vp->v_type != VSOCK) {
180 		releasef(sock);
181 		*errorp = ENOTSOCK;
182 		eprintline(*errorp);
183 		return (NULL);
184 	}
185 	/*
186 	 * Use the stream head to find the real socket vnode.
187 	 * This is needed when namefs sits above sockfs.
188 	 */
189 	if (vp->v_stream) {
190 		ASSERT(vp->v_stream->sd_vnode);
191 		vp = vp->v_stream->sd_vnode;
192 
193 		so = VTOSO(vp);
194 		if (so->so_version == SOV_STREAM) {
195 			releasef(sock);
196 			*errorp = ENOTSOCK;
197 			eprintsoline(so, *errorp);
198 			return (NULL);
199 		}
200 	} else {
201 		so = VTOSO(vp);
202 	}
203 	if (fpp)
204 		*fpp = fp;
205 	return (so);
206 }
207 
208 /*
209  * Allocate and copyin a sockaddr.
210  * Ensures NULL termination for AF_UNIX addresses by extending them
211  * with one NULL byte if need be. Verifies that the length is not
212  * excessive to prevent an application from consuming all of kernel
213  * memory. Returns NULL when an error occurred.
214  */
215 static struct sockaddr *
216 copyin_name(struct sonode *so, struct sockaddr *name, socklen_t *namelenp,
217     int *errorp)
218 {
219 	char	*faddr;
220 	size_t	namelen = (size_t)*namelenp;
221 
222 	ASSERT(namelen != 0);
223 	if (namelen > SO_MAXARGSIZE) {
224 		*errorp = EINVAL;
225 		eprintsoline(so, *errorp);
226 		return (NULL);
227 	}
228 
229 	faddr = (char *)kmem_alloc(namelen, KM_SLEEP);
230 	if (copyin(name, faddr, namelen)) {
231 		kmem_free(faddr, namelen);
232 		*errorp = EFAULT;
233 		eprintsoline(so, *errorp);
234 		return (NULL);
235 	}
236 
237 	/*
238 	 * Add space for NULL termination if needed.
239 	 * Do a quick check if the last byte is NUL.
240 	 */
241 	if (so->so_family == AF_UNIX && faddr[namelen - 1] != '\0') {
242 		/* Check if there is any NULL termination */
243 		size_t	i;
244 		int foundnull = 0;
245 
246 		for (i = sizeof (name->sa_family); i < namelen; i++) {
247 			if (faddr[i] == '\0') {
248 				foundnull = 1;
249 				break;
250 			}
251 		}
252 		if (!foundnull) {
253 			/* Add extra byte for NUL padding */
254 			char *nfaddr;
255 
256 			nfaddr = (char *)kmem_alloc(namelen + 1, KM_SLEEP);
257 			bcopy(faddr, nfaddr, namelen);
258 			kmem_free(faddr, namelen);
259 
260 			/* NUL terminate */
261 			nfaddr[namelen] = '\0';
262 			namelen++;
263 			ASSERT((socklen_t)namelen == namelen);
264 			*namelenp = (socklen_t)namelen;
265 			faddr = nfaddr;
266 		}
267 	}
268 	return ((struct sockaddr *)faddr);
269 }
270 
271 /*
272  * Copy from kaddr/klen to uaddr/ulen. Updates ulenp if non-NULL.
273  */
274 static int
275 copyout_arg(void *uaddr, socklen_t ulen, void *ulenp, void *kaddr,
276     socklen_t klen)
277 {
278 	if (uaddr != NULL) {
279 		if (ulen > klen)
280 			ulen = klen;
281 
282 		if (ulen != 0) {
283 			if (copyout(kaddr, uaddr, ulen))
284 				return (EFAULT);
285 		}
286 	} else
287 		ulen = 0;
288 
289 	if (ulenp != NULL) {
290 		if (copyout(&ulen, ulenp, sizeof (ulen)))
291 			return (EFAULT);
292 	}
293 	return (0);
294 }
295 
296 /*
297  * Copy from kaddr/klen to uaddr/ulen. Updates ulenp if non-NULL.
298  * If klen is greater than ulen it still uses the non-truncated
299  * klen to update ulenp.
300  */
301 static int
302 copyout_name(void *uaddr, socklen_t ulen, void *ulenp, void *kaddr,
303     socklen_t klen)
304 {
305 	if (uaddr != NULL) {
306 		if (ulen >= klen)
307 			ulen = klen;
308 		else if (ulen != 0 && xnet_truncate_print) {
309 			printf("sockfs: truncating copyout of address using "
310 			    "XNET semantics for pid = %d. Lengths %d, %d\n",
311 			    curproc->p_pid, klen, ulen);
312 		}
313 
314 		if (ulen != 0) {
315 			if (copyout(kaddr, uaddr, ulen))
316 				return (EFAULT);
317 		} else
318 			klen = 0;
319 	} else
320 		klen = 0;
321 
322 	if (ulenp != NULL) {
323 		if (copyout(&klen, ulenp, sizeof (klen)))
324 			return (EFAULT);
325 	}
326 	return (0);
327 }
328 
329 /*
330  * The socketpair() code in libsocket creates two sockets (using
331  * the /etc/netconfig fallback if needed) before calling this routine
332  * to connect the two sockets together.
333  *
334  * For a SOCK_STREAM socketpair a listener is needed - in that case this
335  * routine will create a new file descriptor as part of accepting the
336  * connection. The library socketpair() will check if svs[2] has changed
337  * in which case it will close the changed fd.
338  *
339  * Note that this code could use the TPI feature of accepting the connection
340  * on the listening endpoint. However, that would require significant changes
341  * to soaccept.
342  */
343 int
344 so_socketpair(int sv[2])
345 {
346 	int svs[2];
347 	struct sonode *so1, *so2;
348 	int error;
349 	int orig_flags;
350 	struct sockaddr_ux *name;
351 	size_t namelen;
352 	sotpi_info_t *sti1;
353 	sotpi_info_t *sti2;
354 
355 	dprint(1, ("so_socketpair(%p)\n", (void *)sv));
356 
357 	error = useracc(sv, sizeof (svs), B_WRITE);
358 	if (error && do_useracc)
359 		return (set_errno(EFAULT));
360 
361 	if (copyin(sv, svs, sizeof (svs)))
362 		return (set_errno(EFAULT));
363 
364 	if ((so1 = getsonode(svs[0], &error, NULL)) == NULL)
365 		return (set_errno(error));
366 
367 	if ((so2 = getsonode(svs[1], &error, NULL)) == NULL) {
368 		releasef(svs[0]);
369 		return (set_errno(error));
370 	}
371 
372 	if (so1->so_family != AF_UNIX || so2->so_family != AF_UNIX) {
373 		error = EOPNOTSUPP;
374 		goto done;
375 	}
376 
377 	sti1 = SOTOTPI(so1);
378 	sti2 = SOTOTPI(so2);
379 
380 	/*
381 	 * The code below makes assumptions about the "sockfs" implementation.
382 	 * So make sure that the correct implementation is really used.
383 	 */
384 	ASSERT(so1->so_ops == &sotpi_sonodeops);
385 	ASSERT(so2->so_ops == &sotpi_sonodeops);
386 
387 	if (so1->so_type == SOCK_DGRAM) {
388 		/*
389 		 * Bind both sockets and connect them with each other.
390 		 * Need to allocate name/namelen for soconnect.
391 		 */
392 		error = socket_bind(so1, NULL, 0, _SOBIND_UNSPEC, CRED());
393 		if (error) {
394 			eprintsoline(so1, error);
395 			goto done;
396 		}
397 		error = socket_bind(so2, NULL, 0, _SOBIND_UNSPEC, CRED());
398 		if (error) {
399 			eprintsoline(so2, error);
400 			goto done;
401 		}
402 		namelen = sizeof (struct sockaddr_ux);
403 		name = kmem_alloc(namelen, KM_SLEEP);
404 		name->sou_family = AF_UNIX;
405 		name->sou_addr = sti2->sti_ux_laddr;
406 		error = socket_connect(so1,
407 		    (struct sockaddr *)name,
408 		    (socklen_t)namelen,
409 		    0, _SOCONNECT_NOXLATE, CRED());
410 		if (error) {
411 			kmem_free(name, namelen);
412 			eprintsoline(so1, error);
413 			goto done;
414 		}
415 		name->sou_addr = sti1->sti_ux_laddr;
416 		error = socket_connect(so2,
417 		    (struct sockaddr *)name,
418 		    (socklen_t)namelen,
419 		    0, _SOCONNECT_NOXLATE, CRED());
420 		kmem_free(name, namelen);
421 		if (error) {
422 			eprintsoline(so2, error);
423 			goto done;
424 		}
425 		releasef(svs[0]);
426 		releasef(svs[1]);
427 	} else {
428 		/*
429 		 * Bind both sockets, with so1 being a listener.
430 		 * Connect so2 to so1 - nonblocking to avoid waiting for
431 		 * soaccept to complete.
432 		 * Accept a connection on so1. Pass out the new fd as sv[0].
433 		 * The library will detect the changed fd and close
434 		 * the original one.
435 		 */
436 		struct sonode *nso;
437 		struct vnode *nvp;
438 		struct file *nfp;
439 		int nfd;
440 
441 		/*
442 		 * We could simply call socket_listen() here (which would do the
443 		 * binding automatically) if the code didn't rely on passing
444 		 * _SOBIND_NOXLATE to the TPI implementation of socket_bind().
445 		 */
446 		error = socket_bind(so1, NULL, 0, _SOBIND_UNSPEC|
447 		    _SOBIND_NOXLATE|_SOBIND_LISTEN|_SOBIND_SOCKETPAIR,
448 		    CRED());
449 		if (error) {
450 			eprintsoline(so1, error);
451 			goto done;
452 		}
453 		error = socket_bind(so2, NULL, 0, _SOBIND_UNSPEC, CRED());
454 		if (error) {
455 			eprintsoline(so2, error);
456 			goto done;
457 		}
458 
459 		namelen = sizeof (struct sockaddr_ux);
460 		name = kmem_alloc(namelen, KM_SLEEP);
461 		name->sou_family = AF_UNIX;
462 		name->sou_addr = sti1->sti_ux_laddr;
463 		error = socket_connect(so2,
464 		    (struct sockaddr *)name,
465 		    (socklen_t)namelen,
466 		    FNONBLOCK, _SOCONNECT_NOXLATE, CRED());
467 		kmem_free(name, namelen);
468 		if (error) {
469 			if (error != EINPROGRESS) {
470 				eprintsoline(so2, error); goto done;
471 			}
472 		}
473 
474 		error = socket_accept(so1, 0, CRED(), &nso);
475 		if (error) {
476 			eprintsoline(so1, error);
477 			goto done;
478 		}
479 
480 		/* wait for so2 being SS_CONNECTED ignoring signals */
481 		mutex_enter(&so2->so_lock);
482 		error = sowaitconnected(so2, 0, 1);
483 		mutex_exit(&so2->so_lock);
484 		if (error != 0) {
485 			(void) socket_close(nso, 0, CRED());
486 			socket_destroy(nso);
487 			eprintsoline(so2, error);
488 			goto done;
489 		}
490 
491 		nvp = SOTOV(nso);
492 		if (error = falloc(nvp, FWRITE|FREAD, &nfp, &nfd)) {
493 			(void) socket_close(nso, 0, CRED());
494 			socket_destroy(nso);
495 			eprintsoline(nso, error);
496 			goto done;
497 		}
498 		/*
499 		 * copy over FNONBLOCK and FNDELAY flags should they exist
500 		 */
501 		if (so1->so_state & SS_NONBLOCK)
502 			nfp->f_flag |= FNONBLOCK;
503 		if (so1->so_state & SS_NDELAY)
504 			nfp->f_flag |= FNDELAY;
505 
506 		/*
507 		 * fill in the entries that falloc reserved
508 		 */
509 		mutex_exit(&nfp->f_tlock);
510 		setf(nfd, nfp);
511 
512 		/*
513 		 * get the original flags before we release
514 		 */
515 		VERIFY(f_getfd_error(svs[0], &orig_flags) == 0);
516 
517 		releasef(svs[0]);
518 		releasef(svs[1]);
519 
520 		/*
521 		 * If FD_CLOEXEC was set on the filedescriptor we're
522 		 * swapping out, we should set it on the new one too.
523 		 */
524 		if (orig_flags & FD_CLOEXEC) {
525 			f_setfd(nfd, FD_CLOEXEC);
526 		}
527 
528 		/*
529 		 * The socketpair library routine will close the original
530 		 * svs[0] when this code passes out a different file
531 		 * descriptor.
532 		 */
533 		svs[0] = nfd;
534 
535 		if (copyout(svs, sv, sizeof (svs))) {
536 			(void) closeandsetf(nfd, NULL);
537 			eprintline(EFAULT);
538 			return (set_errno(EFAULT));
539 		}
540 	}
541 	return (0);
542 
543 done:
544 	releasef(svs[0]);
545 	releasef(svs[1]);
546 	return (set_errno(error));
547 }
548 
549 int
550 bind(int sock, struct sockaddr *name, socklen_t namelen, int version)
551 {
552 	struct sonode *so;
553 	int error;
554 
555 	dprint(1, ("bind(%d, %p, %d)\n",
556 	    sock, (void *)name, namelen));
557 
558 	if ((so = getsonode(sock, &error, NULL)) == NULL)
559 		return (set_errno(error));
560 
561 	/* Allocate and copyin name */
562 	/*
563 	 * X/Open test does not expect EFAULT with NULL name and non-zero
564 	 * namelen.
565 	 */
566 	if (name != NULL && namelen != 0) {
567 		ASSERT(MUTEX_NOT_HELD(&so->so_lock));
568 		name = copyin_name(so, name, &namelen, &error);
569 		if (name == NULL) {
570 			releasef(sock);
571 			return (set_errno(error));
572 		}
573 	} else {
574 		name = NULL;
575 		namelen = 0;
576 	}
577 
578 	switch (version) {
579 	default:
580 		error = socket_bind(so, name, namelen, 0, CRED());
581 		break;
582 	case SOV_XPG4_2:
583 		error = socket_bind(so, name, namelen, _SOBIND_XPG4_2, CRED());
584 		break;
585 	case SOV_SOCKBSD:
586 		error = socket_bind(so, name, namelen, _SOBIND_SOCKBSD, CRED());
587 		break;
588 	}
589 done:
590 	releasef(sock);
591 	if (name != NULL)
592 		kmem_free(name, (size_t)namelen);
593 
594 	if (error)
595 		return (set_errno(error));
596 	return (0);
597 }
598 
599 /* ARGSUSED2 */
600 int
601 listen(int sock, int backlog, int version)
602 {
603 	struct sonode *so;
604 	int error;
605 
606 	dprint(1, ("listen(%d, %d)\n",
607 	    sock, backlog));
608 
609 	if ((so = getsonode(sock, &error, NULL)) == NULL)
610 		return (set_errno(error));
611 
612 	error = socket_listen(so, backlog, CRED());
613 
614 	releasef(sock);
615 	if (error)
616 		return (set_errno(error));
617 	return (0);
618 }
619 
620 /*ARGSUSED3*/
621 int
622 accept(int sock, struct sockaddr *name, socklen_t *namelenp, int version,
623     int flags)
624 {
625 	struct sonode *so;
626 	file_t *fp;
627 	int error;
628 	socklen_t namelen;
629 	struct sonode *nso;
630 	struct vnode *nvp;
631 	struct file *nfp;
632 	int nfd;
633 	int ssflags;
634 	struct sockaddr *addrp;
635 	socklen_t addrlen;
636 
637 	dprint(1, ("accept(%d, %p, %p)\n",
638 	    sock, (void *)name, (void *)namelenp));
639 
640 	if (flags & ~(SOCK_CLOEXEC|SOCK_NONBLOCK|SOCK_NDELAY)) {
641 		return (set_errno(EINVAL));
642 	}
643 
644 	/* Translate SOCK_ flags to their SS_ variant */
645 	ssflags = 0;
646 	if (flags & SOCK_NONBLOCK)
647 		ssflags |= SS_NONBLOCK;
648 	if (flags & SOCK_NDELAY)
649 		ssflags |= SS_NDELAY;
650 
651 	if ((so = getsonode(sock, &error, &fp)) == NULL)
652 		return (set_errno(error));
653 
654 	if (name != NULL) {
655 		ASSERT(MUTEX_NOT_HELD(&so->so_lock));
656 		if (copyin(namelenp, &namelen, sizeof (namelen))) {
657 			releasef(sock);
658 			return (set_errno(EFAULT));
659 		}
660 		if (namelen != 0) {
661 			error = useracc(name, (size_t)namelen, B_WRITE);
662 			if (error && do_useracc) {
663 				releasef(sock);
664 				return (set_errno(EFAULT));
665 			}
666 		} else
667 			name = NULL;
668 	} else {
669 		namelen = 0;
670 	}
671 
672 	/*
673 	 * Allocate the user fd before socket_accept() in order to
674 	 * catch EMFILE errors before calling socket_accept().
675 	 */
676 	if ((nfd = ufalloc(0)) == -1) {
677 		eprintsoline(so, EMFILE);
678 		releasef(sock);
679 		return (set_errno(EMFILE));
680 	}
681 	error = socket_accept(so, fp->f_flag, CRED(), &nso);
682 	if (error) {
683 		setf(nfd, NULL);
684 		releasef(sock);
685 		return (set_errno(error));
686 	}
687 
688 	nvp = SOTOV(nso);
689 
690 	ASSERT(MUTEX_NOT_HELD(&nso->so_lock));
691 	if (namelen != 0) {
692 		addrlen = so->so_max_addr_len;
693 		addrp = (struct sockaddr *)kmem_alloc(addrlen, KM_SLEEP);
694 
695 		if ((error = socket_getpeername(nso, (struct sockaddr *)addrp,
696 		    &addrlen, B_TRUE, CRED())) == 0) {
697 			error = copyout_name(name, namelen, namelenp,
698 			    addrp, addrlen);
699 		} else {
700 			ASSERT(error == EINVAL || error == ENOTCONN);
701 			error = ECONNABORTED;
702 		}
703 		kmem_free(addrp, so->so_max_addr_len);
704 	}
705 
706 	if (error) {
707 		setf(nfd, NULL);
708 		(void) socket_close(nso, 0, CRED());
709 		socket_destroy(nso);
710 		releasef(sock);
711 		return (set_errno(error));
712 	}
713 	if (error = falloc(NULL, FWRITE|FREAD, &nfp, NULL)) {
714 		setf(nfd, NULL);
715 		(void) socket_close(nso, 0, CRED());
716 		socket_destroy(nso);
717 		eprintsoline(so, error);
718 		releasef(sock);
719 		return (set_errno(error));
720 	}
721 	/*
722 	 * fill in the entries that falloc reserved
723 	 */
724 	nfp->f_vnode = nvp;
725 	mutex_exit(&nfp->f_tlock);
726 	setf(nfd, nfp);
727 
728 	/*
729 	 * Act on SOCK_CLOEXEC from flags
730 	 */
731 	if (flags & SOCK_CLOEXEC) {
732 		f_setfd(nfd, FD_CLOEXEC);
733 	}
734 
735 	/*
736 	 * Copy FNDELAY and FNONBLOCK from listener to acceptor
737 	 * and from ssflags
738 	 */
739 	if ((ssflags | so->so_state) & (SS_NDELAY|SS_NONBLOCK)) {
740 		uint_t oflag = nfp->f_flag;
741 		int arg = 0;
742 
743 		if ((ssflags | so->so_state) & SS_NONBLOCK)
744 			arg |= FNONBLOCK;
745 		else if ((ssflags | so->so_state) & SS_NDELAY)
746 			arg |= FNDELAY;
747 
748 		/*
749 		 * This code is a simplification of the F_SETFL code in fcntl()
750 		 * Ignore any errors from VOP_SETFL.
751 		 */
752 		if ((error = VOP_SETFL(nvp, oflag, arg, nfp->f_cred, NULL))
753 		    != 0) {
754 			eprintsoline(so, error);
755 			error = 0;
756 		} else {
757 			mutex_enter(&nfp->f_tlock);
758 			nfp->f_flag &= ~FMASK | (FREAD|FWRITE);
759 			nfp->f_flag |= arg;
760 			mutex_exit(&nfp->f_tlock);
761 		}
762 	}
763 	releasef(sock);
764 	return (nfd);
765 }
766 
767 int
768 connect(int sock, struct sockaddr *name, socklen_t namelen, int version)
769 {
770 	struct sonode *so;
771 	file_t *fp;
772 	int error;
773 
774 	dprint(1, ("connect(%d, %p, %d)\n",
775 	    sock, (void *)name, namelen));
776 
777 	if ((so = getsonode(sock, &error, &fp)) == NULL)
778 		return (set_errno(error));
779 
780 	/* Allocate and copyin name */
781 	if (namelen != 0) {
782 		ASSERT(MUTEX_NOT_HELD(&so->so_lock));
783 		name = copyin_name(so, name, &namelen, &error);
784 		if (name == NULL) {
785 			releasef(sock);
786 			return (set_errno(error));
787 		}
788 	} else
789 		name = NULL;
790 
791 	error = socket_connect(so, name, namelen, fp->f_flag,
792 	    (version != SOV_XPG4_2) ? 0 : _SOCONNECT_XPG4_2, CRED());
793 	releasef(sock);
794 	if (name)
795 		kmem_free(name, (size_t)namelen);
796 	if (error)
797 		return (set_errno(error));
798 	return (0);
799 }
800 
801 /*ARGSUSED2*/
802 int
803 shutdown(int sock, int how, int version)
804 {
805 	struct sonode *so;
806 	int error;
807 
808 	dprint(1, ("shutdown(%d, %d)\n",
809 	    sock, how));
810 
811 	if ((so = getsonode(sock, &error, NULL)) == NULL)
812 		return (set_errno(error));
813 
814 	error = socket_shutdown(so, how, CRED());
815 
816 	releasef(sock);
817 	if (error)
818 		return (set_errno(error));
819 	return (0);
820 }
821 
822 /*
823  * Common receive routine.
824  */
825 static ssize_t
826 recvit(int sock, struct nmsghdr *msg, struct uio *uiop, int flags,
827     socklen_t *namelenp, socklen_t *controllenp, int *flagsp)
828 {
829 	struct sonode *so;
830 	file_t *fp;
831 	void *name;
832 	socklen_t namelen;
833 	void *control;
834 	socklen_t controllen;
835 	ssize_t len;
836 	int error;
837 
838 	if ((so = getsonode(sock, &error, &fp)) == NULL)
839 		return (set_errno(error));
840 
841 	len = uiop->uio_resid;
842 	uiop->uio_fmode = fp->f_flag;
843 	uiop->uio_extflg = UIO_COPY_CACHED;
844 
845 	name = msg->msg_name;
846 	namelen = msg->msg_namelen;
847 	control = msg->msg_control;
848 	controllen = msg->msg_controllen;
849 
850 	msg->msg_flags = flags & (MSG_OOB | MSG_PEEK | MSG_WAITALL |
851 	    MSG_DONTWAIT | MSG_XPG4_2);
852 
853 	error = socket_recvmsg(so, msg, uiop, CRED());
854 	if (error) {
855 		releasef(sock);
856 		return (set_errno(error));
857 	}
858 	lwp_stat_update(LWP_STAT_MSGRCV, 1);
859 	releasef(sock);
860 
861 	error = copyout_name(name, namelen, namelenp,
862 	    msg->msg_name, msg->msg_namelen);
863 	if (error)
864 		goto err;
865 
866 	if (flagsp != NULL) {
867 		/*
868 		 * Clear internal flag.
869 		 */
870 		msg->msg_flags &= ~MSG_XPG4_2;
871 
872 		/*
873 		 * Determine MSG_CTRUNC. sorecvmsg sets MSG_CTRUNC only
874 		 * when controllen is zero and there is control data to
875 		 * copy out.
876 		 */
877 		if (controllen != 0 &&
878 		    (msg->msg_controllen > controllen || control == NULL)) {
879 			dprint(1, ("recvit: CTRUNC %d %d %p\n",
880 			    msg->msg_controllen, controllen, control));
881 
882 			msg->msg_flags |= MSG_CTRUNC;
883 		}
884 		if (copyout(&msg->msg_flags, flagsp,
885 		    sizeof (msg->msg_flags))) {
886 			error = EFAULT;
887 			goto err;
888 		}
889 	}
890 	/*
891 	 * Note: This MUST be done last. There can be no "goto err" after this
892 	 * point since it could make so_closefds run twice on some part
893 	 * of the file descriptor array.
894 	 */
895 	if (controllen != 0) {
896 		if (!(flags & MSG_XPG4_2)) {
897 			/*
898 			 * Good old msg_accrights can only return a multiple
899 			 * of 4 bytes.
900 			 */
901 			controllen &= ~((int)sizeof (uint32_t) - 1);
902 		}
903 		error = copyout_arg(control, controllen, controllenp,
904 		    msg->msg_control, msg->msg_controllen);
905 		if (error)
906 			goto err;
907 
908 		if (msg->msg_controllen > controllen || control == NULL) {
909 			if (control == NULL)
910 				controllen = 0;
911 			so_closefds(msg->msg_control, msg->msg_controllen,
912 			    !(flags & MSG_XPG4_2), controllen);
913 		}
914 	}
915 	if (msg->msg_namelen != 0)
916 		kmem_free(msg->msg_name, (size_t)msg->msg_namelen);
917 	if (msg->msg_controllen != 0)
918 		kmem_free(msg->msg_control, (size_t)msg->msg_controllen);
919 	return (len - uiop->uio_resid);
920 
921 err:
922 	/*
923 	 * If we fail and the control part contains file descriptors
924 	 * we have to close the fd's.
925 	 */
926 	if (msg->msg_controllen != 0)
927 		so_closefds(msg->msg_control, msg->msg_controllen,
928 		    !(flags & MSG_XPG4_2), 0);
929 	if (msg->msg_namelen != 0)
930 		kmem_free(msg->msg_name, (size_t)msg->msg_namelen);
931 	if (msg->msg_controllen != 0)
932 		kmem_free(msg->msg_control, (size_t)msg->msg_controllen);
933 	return (set_errno(error));
934 }
935 
936 /*
937  * Native system call
938  */
939 ssize_t
940 recv(int sock, void *buffer, size_t len, int flags)
941 {
942 	struct nmsghdr lmsg;
943 	struct uio auio;
944 	struct iovec aiov[1];
945 
946 	dprint(1, ("recv(%d, %p, %ld, %d)\n",
947 	    sock, buffer, len, flags));
948 
949 	if ((ssize_t)len < 0) {
950 		return (set_errno(EINVAL));
951 	}
952 
953 	aiov[0].iov_base = buffer;
954 	aiov[0].iov_len = len;
955 	auio.uio_loffset = 0;
956 	auio.uio_iov = aiov;
957 	auio.uio_iovcnt = 1;
958 	auio.uio_resid = len;
959 	auio.uio_segflg = UIO_USERSPACE;
960 	auio.uio_limit = 0;
961 
962 	lmsg.msg_namelen = 0;
963 	lmsg.msg_controllen = 0;
964 	lmsg.msg_flags = 0;
965 	return (recvit(sock, &lmsg, &auio, flags, NULL, NULL, NULL));
966 }
967 
968 ssize_t
969 recvfrom(int sock, void *buffer, size_t len, int flags, struct sockaddr *name,
970     socklen_t *namelenp)
971 {
972 	struct nmsghdr lmsg;
973 	struct uio auio;
974 	struct iovec aiov[1];
975 
976 	dprint(1, ("recvfrom(%d, %p, %ld, %d, %p, %p)\n",
977 	    sock, buffer, len, flags, (void *)name, (void *)namelenp));
978 
979 	if ((ssize_t)len < 0) {
980 		return (set_errno(EINVAL));
981 	}
982 
983 	aiov[0].iov_base = buffer;
984 	aiov[0].iov_len = len;
985 	auio.uio_loffset = 0;
986 	auio.uio_iov = aiov;
987 	auio.uio_iovcnt = 1;
988 	auio.uio_resid = len;
989 	auio.uio_segflg = UIO_USERSPACE;
990 	auio.uio_limit = 0;
991 
992 	lmsg.msg_name = (char *)name;
993 	if (namelenp != NULL) {
994 		if (copyin(namelenp, &lmsg.msg_namelen,
995 		    sizeof (lmsg.msg_namelen)))
996 			return (set_errno(EFAULT));
997 	} else {
998 		lmsg.msg_namelen = 0;
999 	}
1000 	lmsg.msg_controllen = 0;
1001 	lmsg.msg_flags = 0;
1002 
1003 	return (recvit(sock, &lmsg, &auio, flags, namelenp, NULL, NULL));
1004 }
1005 
1006 /*
1007  * Uses the MSG_XPG4_2 flag to determine if the caller is using
1008  * struct omsghdr or struct nmsghdr.
1009  */
1010 ssize_t
1011 recvmsg(int sock, struct nmsghdr *msg, int flags)
1012 {
1013 	STRUCT_DECL(nmsghdr, u_lmsg);
1014 	STRUCT_HANDLE(nmsghdr, umsgptr);
1015 	struct nmsghdr lmsg;
1016 	struct uio auio;
1017 	struct iovec buf[IOV_MAX_STACK], *aiov = buf;
1018 	ssize_t iovsize = 0;
1019 	int iovcnt;
1020 	ssize_t len, rval;
1021 	int i;
1022 	int *flagsp;
1023 	model_t	model;
1024 
1025 	dprint(1, ("recvmsg(%d, %p, %d)\n",
1026 	    sock, (void *)msg, flags));
1027 
1028 	model = get_udatamodel();
1029 	STRUCT_INIT(u_lmsg, model);
1030 	STRUCT_SET_HANDLE(umsgptr, model, msg);
1031 
1032 	if (flags & MSG_XPG4_2) {
1033 		if (copyin(msg, STRUCT_BUF(u_lmsg), STRUCT_SIZE(u_lmsg)))
1034 			return (set_errno(EFAULT));
1035 		flagsp = STRUCT_FADDR(umsgptr, msg_flags);
1036 	} else {
1037 		/*
1038 		 * Assumes that nmsghdr and omsghdr are identically shaped
1039 		 * except for the added msg_flags field.
1040 		 */
1041 		if (copyin(msg, STRUCT_BUF(u_lmsg),
1042 		    SIZEOF_STRUCT(omsghdr, model)))
1043 			return (set_errno(EFAULT));
1044 		STRUCT_FSET(u_lmsg, msg_flags, 0);
1045 		flagsp = NULL;
1046 	}
1047 
1048 	/*
1049 	 * Code below us will kmem_alloc memory and hang it
1050 	 * off msg_control and msg_name fields. This forces
1051 	 * us to copy the structure to its native form.
1052 	 */
1053 	lmsg.msg_name = STRUCT_FGETP(u_lmsg, msg_name);
1054 	lmsg.msg_namelen = STRUCT_FGET(u_lmsg, msg_namelen);
1055 	lmsg.msg_iov = STRUCT_FGETP(u_lmsg, msg_iov);
1056 	lmsg.msg_iovlen = STRUCT_FGET(u_lmsg, msg_iovlen);
1057 	lmsg.msg_control = STRUCT_FGETP(u_lmsg, msg_control);
1058 	lmsg.msg_controllen = STRUCT_FGET(u_lmsg, msg_controllen);
1059 	lmsg.msg_flags = STRUCT_FGET(u_lmsg, msg_flags);
1060 
1061 	iovcnt = lmsg.msg_iovlen;
1062 
1063 	if (iovcnt <= 0 || iovcnt > IOV_MAX) {
1064 		return (set_errno(EMSGSIZE));
1065 	}
1066 
1067 	if (iovcnt > IOV_MAX_STACK) {
1068 		iovsize = iovcnt * sizeof (struct iovec);
1069 		aiov = kmem_alloc(iovsize, KM_SLEEP);
1070 	}
1071 
1072 #ifdef _SYSCALL32_IMPL
1073 	/*
1074 	 * 32-bit callers need to have their iovec expanded, while ensuring
1075 	 * that they can't move more than 2Gbytes of data in a single call.
1076 	 */
1077 	if (model == DATAMODEL_ILP32) {
1078 		struct iovec32 buf32[IOV_MAX_STACK], *aiov32 = buf32;
1079 		ssize_t iov32size;
1080 		ssize32_t count32;
1081 
1082 		iov32size = iovcnt * sizeof (struct iovec32);
1083 		if (iovsize != 0)
1084 			aiov32 = kmem_alloc(iov32size, KM_SLEEP);
1085 
1086 		if (copyin((struct iovec32 *)lmsg.msg_iov, aiov32, iov32size)) {
1087 			if (iovsize != 0) {
1088 				kmem_free(aiov32, iov32size);
1089 				kmem_free(aiov, iovsize);
1090 			}
1091 
1092 			return (set_errno(EFAULT));
1093 		}
1094 
1095 		count32 = 0;
1096 		for (i = 0; i < iovcnt; i++) {
1097 			ssize32_t iovlen32;
1098 
1099 			iovlen32 = aiov32[i].iov_len;
1100 			count32 += iovlen32;
1101 			if (iovlen32 < 0 || count32 < 0) {
1102 				if (iovsize != 0) {
1103 					kmem_free(aiov32, iov32size);
1104 					kmem_free(aiov, iovsize);
1105 				}
1106 
1107 				return (set_errno(EINVAL));
1108 			}
1109 
1110 			aiov[i].iov_len = iovlen32;
1111 			aiov[i].iov_base =
1112 			    (caddr_t)(uintptr_t)aiov32[i].iov_base;
1113 		}
1114 
1115 		if (iovsize != 0)
1116 			kmem_free(aiov32, iov32size);
1117 	} else
1118 #endif /* _SYSCALL32_IMPL */
1119 	if (copyin(lmsg.msg_iov, aiov, iovcnt * sizeof (struct iovec))) {
1120 		if (iovsize != 0)
1121 			kmem_free(aiov, iovsize);
1122 
1123 		return (set_errno(EFAULT));
1124 	}
1125 	len = 0;
1126 	for (i = 0; i < iovcnt; i++) {
1127 		ssize_t iovlen = aiov[i].iov_len;
1128 		len += iovlen;
1129 		if (iovlen < 0 || len < 0) {
1130 			if (iovsize != 0)
1131 				kmem_free(aiov, iovsize);
1132 
1133 			return (set_errno(EINVAL));
1134 		}
1135 	}
1136 	auio.uio_loffset = 0;
1137 	auio.uio_iov = aiov;
1138 	auio.uio_iovcnt = iovcnt;
1139 	auio.uio_resid = len;
1140 	auio.uio_segflg = UIO_USERSPACE;
1141 	auio.uio_limit = 0;
1142 
1143 	if (lmsg.msg_control != NULL &&
1144 	    (do_useracc == 0 ||
1145 	    useracc(lmsg.msg_control, lmsg.msg_controllen,
1146 	    B_WRITE) != 0)) {
1147 		if (iovsize != 0)
1148 			kmem_free(aiov, iovsize);
1149 
1150 		return (set_errno(EFAULT));
1151 	}
1152 
1153 	rval = recvit(sock, &lmsg, &auio, flags,
1154 	    STRUCT_FADDR(umsgptr, msg_namelen),
1155 	    STRUCT_FADDR(umsgptr, msg_controllen), flagsp);
1156 
1157 	if (iovsize != 0)
1158 		kmem_free(aiov, iovsize);
1159 
1160 	return (rval);
1161 }
1162 
1163 /*
1164  * Common send function.
1165  */
1166 static ssize_t
1167 sendit(int sock, struct nmsghdr *msg, struct uio *uiop, int flags)
1168 {
1169 	struct sonode *so;
1170 	file_t *fp;
1171 	void *name;
1172 	socklen_t namelen;
1173 	void *control;
1174 	socklen_t controllen;
1175 	ssize_t len;
1176 	int error;
1177 
1178 	if ((so = getsonode(sock, &error, &fp)) == NULL)
1179 		return (set_errno(error));
1180 
1181 	uiop->uio_fmode = fp->f_flag;
1182 
1183 	if (so->so_family == AF_UNIX)
1184 		uiop->uio_extflg = UIO_COPY_CACHED;
1185 	else
1186 		uiop->uio_extflg = UIO_COPY_DEFAULT;
1187 
1188 	/* Allocate and copyin name and control */
1189 	name = msg->msg_name;
1190 	namelen = msg->msg_namelen;
1191 	if (name != NULL && namelen != 0) {
1192 		ASSERT(MUTEX_NOT_HELD(&so->so_lock));
1193 		name = copyin_name(so,
1194 		    (struct sockaddr *)name,
1195 		    &namelen, &error);
1196 		if (name == NULL)
1197 			goto done3;
1198 		/* copyin_name null terminates addresses for AF_UNIX */
1199 		msg->msg_namelen = namelen;
1200 		msg->msg_name = name;
1201 	} else {
1202 		msg->msg_name = name = NULL;
1203 		msg->msg_namelen = namelen = 0;
1204 	}
1205 
1206 	control = msg->msg_control;
1207 	controllen = msg->msg_controllen;
1208 	if ((control != NULL) && (controllen != 0)) {
1209 		/*
1210 		 * Verify that the length is not excessive to prevent
1211 		 * an application from consuming all of kernel memory.
1212 		 */
1213 		if (controllen > SO_MAXARGSIZE) {
1214 			error = EINVAL;
1215 			goto done2;
1216 		}
1217 		control = kmem_alloc(controllen, KM_SLEEP);
1218 
1219 		ASSERT(MUTEX_NOT_HELD(&so->so_lock));
1220 		if (copyin(msg->msg_control, control, controllen)) {
1221 			error = EFAULT;
1222 			goto done1;
1223 		}
1224 		msg->msg_control = control;
1225 	} else {
1226 		msg->msg_control = control = NULL;
1227 		msg->msg_controllen = controllen = 0;
1228 	}
1229 
1230 	len = uiop->uio_resid;
1231 	msg->msg_flags = flags;
1232 
1233 	error = socket_sendmsg(so, msg, uiop, CRED());
1234 done1:
1235 	if (control != NULL)
1236 		kmem_free(control, controllen);
1237 done2:
1238 	if (name != NULL)
1239 		kmem_free(name, namelen);
1240 done3:
1241 	if (error != 0) {
1242 		releasef(sock);
1243 		return (set_errno(error));
1244 	}
1245 	lwp_stat_update(LWP_STAT_MSGSND, 1);
1246 	releasef(sock);
1247 	return (len - uiop->uio_resid);
1248 }
1249 
1250 /*
1251  * Native system call
1252  */
1253 ssize_t
1254 send(int sock, void *buffer, size_t len, int flags)
1255 {
1256 	struct nmsghdr lmsg;
1257 	struct uio auio;
1258 	struct iovec aiov[1];
1259 
1260 	dprint(1, ("send(%d, %p, %ld, %d)\n",
1261 	    sock, buffer, len, flags));
1262 
1263 	if ((ssize_t)len < 0) {
1264 		return (set_errno(EINVAL));
1265 	}
1266 
1267 	aiov[0].iov_base = buffer;
1268 	aiov[0].iov_len = len;
1269 	auio.uio_loffset = 0;
1270 	auio.uio_iov = aiov;
1271 	auio.uio_iovcnt = 1;
1272 	auio.uio_resid = len;
1273 	auio.uio_segflg = UIO_USERSPACE;
1274 	auio.uio_limit = 0;
1275 
1276 	lmsg.msg_name = NULL;
1277 	lmsg.msg_control = NULL;
1278 	if (!(flags & MSG_XPG4_2)) {
1279 		/*
1280 		 * In order to be compatible with the libsocket/sockmod
1281 		 * implementation we set EOR for all send* calls.
1282 		 */
1283 		flags |= MSG_EOR;
1284 	}
1285 	return (sendit(sock, &lmsg, &auio, flags));
1286 }
1287 
1288 /*
1289  * Uses the MSG_XPG4_2 flag to determine if the caller is using
1290  * struct omsghdr or struct nmsghdr.
1291  */
1292 ssize_t
1293 sendmsg(int sock, struct nmsghdr *msg, int flags)
1294 {
1295 	struct nmsghdr lmsg;
1296 	STRUCT_DECL(nmsghdr, u_lmsg);
1297 	struct uio auio;
1298 	struct iovec buf[IOV_MAX_STACK], *aiov = buf;
1299 	ssize_t iovsize = 0;
1300 	int iovcnt;
1301 	ssize_t len, rval;
1302 	int i;
1303 	model_t	model;
1304 
1305 	dprint(1, ("sendmsg(%d, %p, %d)\n", sock, (void *)msg, flags));
1306 
1307 	model = get_udatamodel();
1308 	STRUCT_INIT(u_lmsg, model);
1309 
1310 	if (flags & MSG_XPG4_2) {
1311 		if (copyin(msg, (char *)STRUCT_BUF(u_lmsg),
1312 		    STRUCT_SIZE(u_lmsg)))
1313 			return (set_errno(EFAULT));
1314 	} else {
1315 		/*
1316 		 * Assumes that nmsghdr and omsghdr are identically shaped
1317 		 * except for the added msg_flags field.
1318 		 */
1319 		if (copyin(msg, (char *)STRUCT_BUF(u_lmsg),
1320 		    SIZEOF_STRUCT(omsghdr, model)))
1321 			return (set_errno(EFAULT));
1322 		/*
1323 		 * In order to be compatible with the libsocket/sockmod
1324 		 * implementation we set EOR for all send* calls.
1325 		 */
1326 		flags |= MSG_EOR;
1327 	}
1328 
1329 	/*
1330 	 * Code below us will kmem_alloc memory and hang it
1331 	 * off msg_control and msg_name fields. This forces
1332 	 * us to copy the structure to its native form.
1333 	 */
1334 	lmsg.msg_name = STRUCT_FGETP(u_lmsg, msg_name);
1335 	lmsg.msg_namelen = STRUCT_FGET(u_lmsg, msg_namelen);
1336 	lmsg.msg_iov = STRUCT_FGETP(u_lmsg, msg_iov);
1337 	lmsg.msg_iovlen = STRUCT_FGET(u_lmsg, msg_iovlen);
1338 	lmsg.msg_control = STRUCT_FGETP(u_lmsg, msg_control);
1339 	lmsg.msg_controllen = STRUCT_FGET(u_lmsg, msg_controllen);
1340 	lmsg.msg_flags = STRUCT_FGET(u_lmsg, msg_flags);
1341 
1342 	iovcnt = lmsg.msg_iovlen;
1343 
1344 	if (iovcnt <= 0 || iovcnt > IOV_MAX) {
1345 		/*
1346 		 * Unless this is XPG 4.2 we allow iovcnt == 0 to
1347 		 * be compatible with SunOS 4.X and 4.4BSD.
1348 		 */
1349 		if (iovcnt != 0 || (flags & MSG_XPG4_2))
1350 			return (set_errno(EMSGSIZE));
1351 	}
1352 
1353 	if (iovcnt > IOV_MAX_STACK) {
1354 		iovsize = iovcnt * sizeof (struct iovec);
1355 		aiov = kmem_alloc(iovsize, KM_SLEEP);
1356 	}
1357 
1358 #ifdef _SYSCALL32_IMPL
1359 	/*
1360 	 * 32-bit callers need to have their iovec expanded, while ensuring
1361 	 * that they can't move more than 2Gbytes of data in a single call.
1362 	 */
1363 	if (model == DATAMODEL_ILP32) {
1364 		struct iovec32 buf32[IOV_MAX_STACK], *aiov32 = buf32;
1365 		ssize_t iov32size;
1366 		ssize32_t count32;
1367 
1368 		iov32size = iovcnt * sizeof (struct iovec32);
1369 		if (iovsize != 0)
1370 			aiov32 = kmem_alloc(iov32size, KM_SLEEP);
1371 
1372 		if (iovcnt != 0 &&
1373 		    copyin((struct iovec32 *)lmsg.msg_iov, aiov32, iov32size)) {
1374 			if (iovsize != 0) {
1375 				kmem_free(aiov32, iov32size);
1376 				kmem_free(aiov, iovsize);
1377 			}
1378 
1379 			return (set_errno(EFAULT));
1380 		}
1381 
1382 		count32 = 0;
1383 		for (i = 0; i < iovcnt; i++) {
1384 			ssize32_t iovlen32;
1385 
1386 			iovlen32 = aiov32[i].iov_len;
1387 			count32 += iovlen32;
1388 			if (iovlen32 < 0 || count32 < 0) {
1389 				if (iovsize != 0) {
1390 					kmem_free(aiov32, iov32size);
1391 					kmem_free(aiov, iovsize);
1392 				}
1393 
1394 				return (set_errno(EINVAL));
1395 			}
1396 
1397 			aiov[i].iov_len = iovlen32;
1398 			aiov[i].iov_base =
1399 			    (caddr_t)(uintptr_t)aiov32[i].iov_base;
1400 		}
1401 
1402 		if (iovsize != 0)
1403 			kmem_free(aiov32, iov32size);
1404 	} else
1405 #endif /* _SYSCALL32_IMPL */
1406 	if (iovcnt != 0 &&
1407 	    copyin(lmsg.msg_iov, aiov,
1408 	    (unsigned)iovcnt * sizeof (struct iovec))) {
1409 		if (iovsize != 0)
1410 			kmem_free(aiov, iovsize);
1411 
1412 		return (set_errno(EFAULT));
1413 	}
1414 	len = 0;
1415 	for (i = 0; i < iovcnt; i++) {
1416 		ssize_t iovlen = aiov[i].iov_len;
1417 		len += iovlen;
1418 		if (iovlen < 0 || len < 0) {
1419 			if (iovsize != 0)
1420 				kmem_free(aiov, iovsize);
1421 
1422 			return (set_errno(EINVAL));
1423 		}
1424 	}
1425 	auio.uio_loffset = 0;
1426 	auio.uio_iov = aiov;
1427 	auio.uio_iovcnt = iovcnt;
1428 	auio.uio_resid = len;
1429 	auio.uio_segflg = UIO_USERSPACE;
1430 	auio.uio_limit = 0;
1431 
1432 	rval = sendit(sock, &lmsg, &auio, flags);
1433 
1434 	if (iovsize != 0)
1435 		kmem_free(aiov, iovsize);
1436 
1437 	return (rval);
1438 }
1439 
1440 ssize_t
1441 sendto(int sock, void *buffer, size_t len, int flags,
1442     struct sockaddr *name, socklen_t namelen)
1443 {
1444 	struct nmsghdr lmsg;
1445 	struct uio auio;
1446 	struct iovec aiov[1];
1447 
1448 	dprint(1, ("sendto(%d, %p, %ld, %d, %p, %d)\n",
1449 	    sock, buffer, len, flags, (void *)name, namelen));
1450 
1451 	if ((ssize_t)len < 0) {
1452 		return (set_errno(EINVAL));
1453 	}
1454 
1455 	aiov[0].iov_base = buffer;
1456 	aiov[0].iov_len = len;
1457 	auio.uio_loffset = 0;
1458 	auio.uio_iov = aiov;
1459 	auio.uio_iovcnt = 1;
1460 	auio.uio_resid = len;
1461 	auio.uio_segflg = UIO_USERSPACE;
1462 	auio.uio_limit = 0;
1463 
1464 	lmsg.msg_name = (char *)name;
1465 	lmsg.msg_namelen = namelen;
1466 	lmsg.msg_control = NULL;
1467 	if (!(flags & MSG_XPG4_2)) {
1468 		/*
1469 		 * In order to be compatible with the libsocket/sockmod
1470 		 * implementation we set EOR for all send* calls.
1471 		 */
1472 		flags |= MSG_EOR;
1473 	}
1474 	return (sendit(sock, &lmsg, &auio, flags));
1475 }
1476 
1477 /*ARGSUSED3*/
1478 int
1479 getpeername(int sock, struct sockaddr *name, socklen_t *namelenp, int version)
1480 {
1481 	struct sonode *so;
1482 	int error;
1483 	socklen_t namelen;
1484 	socklen_t sock_addrlen;
1485 	struct sockaddr *sock_addrp;
1486 
1487 	dprint(1, ("getpeername(%d, %p, %p)\n",
1488 	    sock, (void *)name, (void *)namelenp));
1489 
1490 	if ((so = getsonode(sock, &error, NULL)) == NULL)
1491 		goto bad;
1492 
1493 	ASSERT(MUTEX_NOT_HELD(&so->so_lock));
1494 	if (copyin(namelenp, &namelen, sizeof (namelen)) ||
1495 	    (name == NULL && namelen != 0)) {
1496 		error = EFAULT;
1497 		goto rel_out;
1498 	}
1499 	sock_addrlen = so->so_max_addr_len;
1500 	sock_addrp = (struct sockaddr *)kmem_alloc(sock_addrlen, KM_SLEEP);
1501 
1502 	if ((error = socket_getpeername(so, sock_addrp, &sock_addrlen,
1503 	    B_FALSE, CRED())) == 0) {
1504 		ASSERT(sock_addrlen <= so->so_max_addr_len);
1505 		error = copyout_name(name, namelen, namelenp,
1506 		    (void *)sock_addrp, sock_addrlen);
1507 	}
1508 	kmem_free(sock_addrp, so->so_max_addr_len);
1509 rel_out:
1510 	releasef(sock);
1511 bad:	return (error != 0 ? set_errno(error) : 0);
1512 }
1513 
1514 /*ARGSUSED3*/
1515 int
1516 getsockname(int sock, struct sockaddr *name, socklen_t *namelenp, int version)
1517 {
1518 	struct sonode *so;
1519 	int error;
1520 	socklen_t namelen, sock_addrlen;
1521 	struct sockaddr *sock_addrp;
1522 
1523 	dprint(1, ("getsockname(%d, %p, %p)\n",
1524 	    sock, (void *)name, (void *)namelenp));
1525 
1526 	if ((so = getsonode(sock, &error, NULL)) == NULL)
1527 		goto bad;
1528 
1529 	ASSERT(MUTEX_NOT_HELD(&so->so_lock));
1530 	if (copyin(namelenp, &namelen, sizeof (namelen)) ||
1531 	    (name == NULL && namelen != 0)) {
1532 		error = EFAULT;
1533 		goto rel_out;
1534 	}
1535 
1536 	sock_addrlen = so->so_max_addr_len;
1537 	sock_addrp = (struct sockaddr *)kmem_alloc(sock_addrlen, KM_SLEEP);
1538 	if ((error = socket_getsockname(so, sock_addrp, &sock_addrlen,
1539 	    CRED())) == 0) {
1540 		ASSERT(MUTEX_NOT_HELD(&so->so_lock));
1541 		ASSERT(sock_addrlen <= so->so_max_addr_len);
1542 		error = copyout_name(name, namelen, namelenp,
1543 		    (void *)sock_addrp, sock_addrlen);
1544 	}
1545 	kmem_free(sock_addrp, so->so_max_addr_len);
1546 rel_out:
1547 	releasef(sock);
1548 bad:	return (error != 0 ? set_errno(error) : 0);
1549 }
1550 
1551 /*ARGSUSED5*/
1552 int
1553 getsockopt(int sock, int level, int option_name, void *option_value,
1554     socklen_t *option_lenp, int version)
1555 {
1556 	struct sonode *so;
1557 	socklen_t optlen, optlen_res;
1558 	void *optval;
1559 	int error;
1560 
1561 	dprint(1, ("getsockopt(%d, %d, %d, %p, %p)\n",
1562 	    sock, level, option_name, option_value, (void *)option_lenp));
1563 
1564 	if ((so = getsonode(sock, &error, NULL)) == NULL)
1565 		return (set_errno(error));
1566 
1567 	ASSERT(MUTEX_NOT_HELD(&so->so_lock));
1568 	if (copyin(option_lenp, &optlen, sizeof (optlen))) {
1569 		releasef(sock);
1570 		return (set_errno(EFAULT));
1571 	}
1572 	/*
1573 	 * Verify that the length is not excessive to prevent
1574 	 * an application from consuming all of kernel memory.
1575 	 */
1576 	if (optlen > SO_MAXARGSIZE) {
1577 		error = EINVAL;
1578 		releasef(sock);
1579 		return (set_errno(error));
1580 	}
1581 	optval = kmem_alloc(optlen, KM_SLEEP);
1582 	optlen_res = optlen;
1583 	error = socket_getsockopt(so, level, option_name, optval,
1584 	    &optlen_res, (version != SOV_XPG4_2) ? 0 : _SOGETSOCKOPT_XPG4_2,
1585 	    CRED());
1586 	releasef(sock);
1587 	if (error) {
1588 		kmem_free(optval, optlen);
1589 		return (set_errno(error));
1590 	}
1591 	error = copyout_arg(option_value, optlen, option_lenp,
1592 	    optval, optlen_res);
1593 	kmem_free(optval, optlen);
1594 	if (error)
1595 		return (set_errno(error));
1596 	return (0);
1597 }
1598 
1599 /*ARGSUSED5*/
1600 int
1601 setsockopt(int sock, int level, int option_name, void *option_value,
1602     socklen_t option_len, int version)
1603 {
1604 	struct sonode *so;
1605 	intptr_t buffer[2];
1606 	void *optval = NULL;
1607 	int error;
1608 
1609 	dprint(1, ("setsockopt(%d, %d, %d, %p, %d)\n",
1610 	    sock, level, option_name, option_value, option_len));
1611 
1612 	if ((so = getsonode(sock, &error, NULL)) == NULL)
1613 		return (set_errno(error));
1614 
1615 	if (option_value != NULL) {
1616 		if (option_len != 0) {
1617 			/*
1618 			 * Verify that the length is not excessive to prevent
1619 			 * an application from consuming all of kernel memory.
1620 			 */
1621 			if (option_len > SO_MAXARGSIZE) {
1622 				error = EINVAL;
1623 				goto done2;
1624 			}
1625 			optval = option_len <= sizeof (buffer) ?
1626 			    &buffer : kmem_alloc((size_t)option_len, KM_SLEEP);
1627 			ASSERT(MUTEX_NOT_HELD(&so->so_lock));
1628 			if (copyin(option_value, optval, (size_t)option_len)) {
1629 				error = EFAULT;
1630 				goto done1;
1631 			}
1632 		}
1633 	} else
1634 		option_len = 0;
1635 
1636 	error = socket_setsockopt(so, level, option_name, optval,
1637 	    (t_uscalar_t)option_len, CRED());
1638 done1:
1639 	if (optval != buffer)
1640 		kmem_free(optval, (size_t)option_len);
1641 done2:
1642 	releasef(sock);
1643 	if (error)
1644 		return (set_errno(error));
1645 	return (0);
1646 }
1647 
1648 static int
1649 sockconf_add_sock(int family, int type, int protocol, char *name)
1650 {
1651 	int error = 0;
1652 	char *kdevpath = NULL;
1653 	char *kmodule = NULL;
1654 	char *buf = NULL;
1655 	size_t pathlen = 0;
1656 	struct sockparams *sp;
1657 
1658 	if (name == NULL)
1659 		return (EINVAL);
1660 	/*
1661 	 * Copyin the name.
1662 	 * This also makes it possible to check for too long pathnames.
1663 	 * Compress the space needed for the name before passing it
1664 	 * to soconfig - soconfig will store the string until
1665 	 * the configuration is removed.
1666 	 */
1667 	buf = kmem_alloc(MAXPATHLEN, KM_SLEEP);
1668 	if ((error = copyinstr(name, buf, MAXPATHLEN, &pathlen)) != 0) {
1669 		kmem_free(buf, MAXPATHLEN);
1670 		return (error);
1671 	}
1672 	if (strncmp(buf, "/dev", strlen("/dev")) == 0) {
1673 		/* For device */
1674 
1675 		/*
1676 		 * Special handling for NCA:
1677 		 *
1678 		 * DEV_NCA is never opened even if an application
1679 		 * requests for AF_NCA. The device opened is instead a
1680 		 * predefined AF_INET transport (NCA_INET_DEV).
1681 		 *
1682 		 * Prior to Volo (PSARC/2007/587) NCA would determine
1683 		 * the device using a lookup, which worked then because
1684 		 * all protocols were based on TPI. Since TPI is no
1685 		 * longer the default, we have to explicitly state
1686 		 * which device to use.
1687 		 */
1688 		if (strcmp(buf, NCA_DEV) == 0) {
1689 			/* only support entry <28, 2, 0> */
1690 			if (family != AF_NCA || type != SOCK_STREAM ||
1691 			    protocol != 0) {
1692 				kmem_free(buf, MAXPATHLEN);
1693 				return (EINVAL);
1694 			}
1695 
1696 			pathlen = strlen(NCA_INET_DEV) + 1;
1697 			kdevpath = kmem_alloc(pathlen, KM_SLEEP);
1698 			bcopy(NCA_INET_DEV, kdevpath, pathlen);
1699 			kdevpath[pathlen - 1] = '\0';
1700 		} else {
1701 			kdevpath = kmem_alloc(pathlen, KM_SLEEP);
1702 			bcopy(buf, kdevpath, pathlen);
1703 			kdevpath[pathlen - 1] = '\0';
1704 		}
1705 	} else {
1706 		/* For socket module */
1707 		kmodule = kmem_alloc(pathlen, KM_SLEEP);
1708 		bcopy(buf, kmodule, pathlen);
1709 		kmodule[pathlen - 1] = '\0';
1710 		pathlen = 0;
1711 	}
1712 	kmem_free(buf, MAXPATHLEN);
1713 
1714 	/* sockparams_create frees mod name and devpath upon failure */
1715 	sp = sockparams_create(family, type, protocol, kmodule,
1716 	    kdevpath, pathlen, 0, KM_SLEEP, &error);
1717 	if (sp != NULL) {
1718 		error = sockparams_add(sp);
1719 		if (error != 0)
1720 			sockparams_destroy(sp);
1721 	}
1722 
1723 	return (error);
1724 }
1725 
1726 static int
1727 sockconf_remove_sock(int family, int type, int protocol)
1728 {
1729 	return (sockparams_delete(family, type, protocol));
1730 }
1731 
1732 static int
1733 sockconfig_remove_filter(const char *uname)
1734 {
1735 	char kname[SOF_MAXNAMELEN];
1736 	size_t len;
1737 	int error;
1738 	sof_entry_t *ent;
1739 
1740 	if ((error = copyinstr(uname, kname, SOF_MAXNAMELEN, &len)) != 0)
1741 		return (error);
1742 
1743 	ent = sof_entry_remove_by_name(kname);
1744 	if (ent == NULL)
1745 		return (ENXIO);
1746 
1747 	mutex_enter(&ent->sofe_lock);
1748 	ASSERT(!(ent->sofe_flags & SOFEF_CONDEMED));
1749 	if (ent->sofe_refcnt == 0) {
1750 		mutex_exit(&ent->sofe_lock);
1751 		sof_entry_free(ent);
1752 	} else {
1753 		/* let the last socket free the filter */
1754 		ent->sofe_flags |= SOFEF_CONDEMED;
1755 		mutex_exit(&ent->sofe_lock);
1756 	}
1757 
1758 	return (0);
1759 }
1760 
1761 static int
1762 sockconfig_add_filter(const char *uname, void *ufilpropp)
1763 {
1764 	struct sockconfig_filter_props filprop;
1765 	sof_entry_t *ent;
1766 	int error;
1767 	size_t tuplesz, len;
1768 	char hintbuf[SOF_MAXNAMELEN];
1769 
1770 	ent = kmem_zalloc(sizeof (sof_entry_t), KM_SLEEP);
1771 	mutex_init(&ent->sofe_lock, NULL, MUTEX_DEFAULT, NULL);
1772 
1773 	if ((error = copyinstr(uname, ent->sofe_name, SOF_MAXNAMELEN,
1774 	    &len)) != 0) {
1775 		sof_entry_free(ent);
1776 		return (error);
1777 	}
1778 
1779 	if (get_udatamodel() == DATAMODEL_NATIVE) {
1780 		if (copyin(ufilpropp, &filprop, sizeof (filprop)) != 0) {
1781 			sof_entry_free(ent);
1782 			return (EFAULT);
1783 		}
1784 	}
1785 #ifdef	_SYSCALL32_IMPL
1786 	else {
1787 		struct sockconfig_filter_props32 filprop32;
1788 
1789 		if (copyin(ufilpropp, &filprop32, sizeof (filprop32)) != 0) {
1790 			sof_entry_free(ent);
1791 			return (EFAULT);
1792 		}
1793 		filprop.sfp_modname = (char *)(uintptr_t)filprop32.sfp_modname;
1794 		filprop.sfp_autoattach = filprop32.sfp_autoattach;
1795 		filprop.sfp_hint = filprop32.sfp_hint;
1796 		filprop.sfp_hintarg = (char *)(uintptr_t)filprop32.sfp_hintarg;
1797 		filprop.sfp_socktuple_cnt = filprop32.sfp_socktuple_cnt;
1798 		filprop.sfp_socktuple =
1799 		    (sof_socktuple_t *)(uintptr_t)filprop32.sfp_socktuple;
1800 	}
1801 #endif	/* _SYSCALL32_IMPL */
1802 
1803 	if ((error = copyinstr(filprop.sfp_modname, ent->sofe_modname,
1804 	    sizeof (ent->sofe_modname), &len)) != 0) {
1805 		sof_entry_free(ent);
1806 		return (error);
1807 	}
1808 
1809 	/*
1810 	 * A filter must specify at least one socket tuple.
1811 	 */
1812 	if (filprop.sfp_socktuple_cnt == 0 ||
1813 	    filprop.sfp_socktuple_cnt > SOF_MAXSOCKTUPLECNT) {
1814 		sof_entry_free(ent);
1815 		return (EINVAL);
1816 	}
1817 	ent->sofe_flags = filprop.sfp_autoattach ? SOFEF_AUTO : SOFEF_PROG;
1818 	ent->sofe_hint = filprop.sfp_hint;
1819 
1820 	/*
1821 	 * Verify the hint, and copy in the hint argument, if necessary.
1822 	 */
1823 	switch (ent->sofe_hint) {
1824 	case SOF_HINT_BEFORE:
1825 	case SOF_HINT_AFTER:
1826 		if ((error = copyinstr(filprop.sfp_hintarg, hintbuf,
1827 		    sizeof (hintbuf), &len)) != 0) {
1828 			sof_entry_free(ent);
1829 			return (error);
1830 		}
1831 		ent->sofe_hintarg = kmem_alloc(len, KM_SLEEP);
1832 		bcopy(hintbuf, ent->sofe_hintarg, len);
1833 		/* FALLTHRU */
1834 	case SOF_HINT_TOP:
1835 	case SOF_HINT_BOTTOM:
1836 		/* hints cannot be used with programmatic filters */
1837 		if (ent->sofe_flags & SOFEF_PROG) {
1838 			sof_entry_free(ent);
1839 			return (EINVAL);
1840 		}
1841 		break;
1842 	case SOF_HINT_NONE:
1843 		break;
1844 	default:
1845 		/* bad hint value */
1846 		sof_entry_free(ent);
1847 		return (EINVAL);
1848 	}
1849 
1850 	ent->sofe_socktuple_cnt = filprop.sfp_socktuple_cnt;
1851 	tuplesz = sizeof (sof_socktuple_t) * ent->sofe_socktuple_cnt;
1852 	ent->sofe_socktuple = kmem_alloc(tuplesz, KM_SLEEP);
1853 
1854 	if (get_udatamodel() == DATAMODEL_NATIVE) {
1855 		if (copyin(filprop.sfp_socktuple, ent->sofe_socktuple,
1856 		    tuplesz)) {
1857 			sof_entry_free(ent);
1858 			return (EFAULT);
1859 		}
1860 	}
1861 #ifdef	_SYSCALL32_IMPL
1862 	else {
1863 		int i;
1864 		caddr_t data = (caddr_t)filprop.sfp_socktuple;
1865 		sof_socktuple_t	*tup = ent->sofe_socktuple;
1866 		sof_socktuple32_t tup32;
1867 
1868 		tup = ent->sofe_socktuple;
1869 		for (i = 0; i < ent->sofe_socktuple_cnt; i++, tup++) {
1870 			ASSERT(tup < ent->sofe_socktuple + tuplesz);
1871 
1872 			if (copyin(data, &tup32, sizeof (tup32)) != 0) {
1873 				sof_entry_free(ent);
1874 				return (EFAULT);
1875 			}
1876 			tup->sofst_family = tup32.sofst_family;
1877 			tup->sofst_type = tup32.sofst_type;
1878 			tup->sofst_protocol = tup32.sofst_protocol;
1879 
1880 			data += sizeof (tup32);
1881 		}
1882 	}
1883 #endif	/* _SYSCALL32_IMPL */
1884 
1885 	/* Sockets can start using the filter as soon as the filter is added */
1886 	if ((error = sof_entry_add(ent)) != 0)
1887 		sof_entry_free(ent);
1888 
1889 	return (error);
1890 }
1891 
1892 /*
1893  * Socket configuration system call. It is used to add and remove
1894  * socket types.
1895  */
1896 int
1897 sockconfig(int cmd, void *arg1, void *arg2, void *arg3, void *arg4)
1898 {
1899 	int error = 0;
1900 
1901 	if (secpolicy_net_config(CRED(), B_FALSE) != 0)
1902 		return (set_errno(EPERM));
1903 
1904 	if (sockfs_defer_nl7c_init) {
1905 		nl7c_init();
1906 		sockfs_defer_nl7c_init = 0;
1907 	}
1908 
1909 	switch (cmd) {
1910 	case SOCKCONFIG_ADD_SOCK:
1911 		error = sockconf_add_sock((int)(uintptr_t)arg1,
1912 		    (int)(uintptr_t)arg2, (int)(uintptr_t)arg3, arg4);
1913 		break;
1914 	case SOCKCONFIG_REMOVE_SOCK:
1915 		error = sockconf_remove_sock((int)(uintptr_t)arg1,
1916 		    (int)(uintptr_t)arg2, (int)(uintptr_t)arg3);
1917 		break;
1918 	case SOCKCONFIG_ADD_FILTER:
1919 		error = sockconfig_add_filter((const char *)arg1, arg2);
1920 		break;
1921 	case SOCKCONFIG_REMOVE_FILTER:
1922 		error = sockconfig_remove_filter((const char *)arg1);
1923 		break;
1924 	case SOCKCONFIG_GET_SOCKTABLE:
1925 		error = sockparams_copyout_socktable((int)(uintptr_t)arg1);
1926 		break;
1927 	default:
1928 #ifdef	DEBUG
1929 		cmn_err(CE_NOTE, "sockconfig: unkonwn subcommand %d", cmd);
1930 #endif
1931 		error = EINVAL;
1932 		break;
1933 	}
1934 
1935 	if (error != 0) {
1936 		eprintline(error);
1937 		return (set_errno(error));
1938 	}
1939 	return (0);
1940 }
1941 
1942 
1943 /*
1944  * Sendfile is implemented through two schemes, direct I/O or by
1945  * caching in the filesystem page cache. We cache the input file by
1946  * default and use direct I/O only if sendfile_max_size is set
1947  * appropriately as explained below. Note that this logic is consistent
1948  * with other filesystems where caching is turned on by default
1949  * unless explicitly turned off by using the DIRECTIO ioctl.
1950  *
1951  * We choose a slightly different scheme here. One can turn off
1952  * caching by setting sendfile_max_size to 0. One can also enable
1953  * caching of files <= sendfile_max_size by setting sendfile_max_size
1954  * to an appropriate value. By default sendfile_max_size is set to the
1955  * maximum value so that all files are cached. In future, we may provide
1956  * better interfaces for caching the file.
1957  *
1958  * Sendfile through Direct I/O (Zero copy)
1959  * --------------------------------------
1960  *
1961  * As disks are normally slower than the network, we can't have a
1962  * single thread that reads the disk and writes to the network. We
1963  * need to have parallelism. This is done by having the sendfile
1964  * thread create another thread that reads from the filesystem
1965  * and queues it for network processing. In this scheme, the data
1966  * is never copied anywhere i.e it is zero copy unlike the other
1967  * scheme.
1968  *
1969  * We have a sendfile queue (snfq) where each sendfile
1970  * request (snf_req_t) is queued for processing by a thread. Number
1971  * of threads is dynamically allocated and they exit if they are idling
1972  * beyond a specified amount of time. When each request (snf_req_t) is
1973  * processed by a thread, it produces a number of mblk_t structures to
1974  * be consumed by the sendfile thread. snf_deque and snf_enque are
1975  * used for consuming and producing mblks. Size of the filesystem
1976  * read is determined by the tunable (sendfile_read_size). A single
1977  * mblk holds sendfile_read_size worth of data (except the last
1978  * read of the file) which is sent down as a whole to the network.
1979  * sendfile_read_size is set to 1 MB as this seems to be the optimal
1980  * value for the UFS filesystem backed by a striped storage array.
1981  *
1982  * Synchronisation between read (producer) and write (consumer) threads.
1983  * --------------------------------------------------------------------
1984  *
1985  * sr_lock protects sr_ib_head and sr_ib_tail. The lock is held while
1986  * adding and deleting items in this list. Error can happen anytime
1987  * during read or write. There could be unprocessed mblks in the
1988  * sr_ib_XXX list when a read or write error occurs. Whenever error
1989  * is encountered, we need two things to happen :
1990  *
1991  * a) One of the threads need to clean the mblks.
1992  * b) When one thread encounters an error, the other should stop.
1993  *
1994  * For (a), we don't want to penalize the reader thread as it could do
1995  * some useful work processing other requests. For (b), the error can
1996  * be detected by examining sr_read_error or sr_write_error.
1997  * sr_lock protects sr_read_error and sr_write_error. If both reader and
1998  * writer encounters error, we need to report the write error back to
1999  * the application as that's what would have happened if the operations
2000  * were done sequentially. With this in mind, following should work :
2001  *
2002  *	- Check for errors before read or write.
2003  *	- If the reader encounters error, set the error in sr_read_error.
2004  *	  Check sr_write_error, if it is set, send cv_signal as it is
2005  *	  waiting for reader to complete. If it is not set, the writer
2006  *	  is either running sinking data to the network or blocked
2007  *        because of flow control. For handling the latter case, we
2008  *	  always send a signal. In any case, it will examine sr_read_error
2009  *	  and return. sr_read_error is marked with SR_READ_DONE to tell
2010  *	  the writer that the reader is done in all the cases.
2011  *	- If the writer encounters error, set the error in sr_write_error.
2012  *	  The reader thread is either blocked because of flow control or
2013  *	  running reading data from the disk. For the former, we need to
2014  *	  wakeup the thread. Again to keep it simple, we always wake up
2015  *	  the reader thread. Then, wait for the read thread to complete
2016  *	  if it is not done yet. Cleanup and return.
2017  *
2018  * High and low water marks for the read thread.
2019  * --------------------------------------------
2020  *
2021  * If sendfile() is used to send data over a slow network, we need to
2022  * make sure that the read thread does not produce data at a faster
2023  * rate than the network. This can happen if the disk is faster than
2024  * the network. In such a case, we don't want to build a very large queue.
2025  * But we would still like to get all of the network throughput possible.
2026  * This implies that network should never block waiting for data.
2027  * As there are lot of disk throughput/network throughput combinations
2028  * possible, it is difficult to come up with an accurate number.
2029  * A typical 10K RPM disk has a max seek latency 17ms and rotational
2030  * latency of 3ms for reading a disk block. Thus, the total latency to
2031  * initiate a new read, transfer data from the disk and queue for
2032  * transmission would take about a max of 25ms. Todays max transfer rate
2033  * for network is 100MB/sec. If the thread is blocked because of flow
2034  * control, it would take 25ms to get new data ready for transmission.
2035  * We have to make sure that network is not idling, while we are initiating
2036  * new transfers. So, at 100MB/sec, to keep network busy we would need
2037  * 2.5MB of data. Rounding off, we keep the low water mark to be 3MB of data.
2038  * We need to pick a high water mark so that the woken up thread would
2039  * do considerable work before blocking again to prevent thrashing. Currently,
2040  * we pick this to be 10 times that of the low water mark.
2041  *
2042  * Sendfile with segmap caching (One copy from page cache to mblks).
2043  * ----------------------------------------------------------------
2044  *
2045  * We use the segmap cache for caching the file, if the size of file
2046  * is <= sendfile_max_size. In this case we don't use threads as VM
2047  * is reasonably fast enough to keep up with the network. If the underlying
2048  * transport allows, we call segmap_getmapflt() to map MAXBSIZE (8K) worth
2049  * of data into segmap space, and use the virtual address from segmap
2050  * directly through desballoc() to avoid copy. Once the transport is done
2051  * with the data, the mapping will be released through segmap_release()
2052  * called by the call-back routine.
2053  *
2054  * If zero-copy is not allowed by the transport, we simply call VOP_READ()
2055  * to copy the data from the filesystem into our temporary network buffer.
2056  *
2057  * To disable caching, set sendfile_max_size to 0.
2058  */
2059 
2060 uint_t sendfile_read_size = 1024 * 1024;
2061 #define	SENDFILE_REQ_LOWAT	3 * 1024 * 1024
2062 uint_t sendfile_req_lowat = SENDFILE_REQ_LOWAT;
2063 uint_t sendfile_req_hiwat = 10 * SENDFILE_REQ_LOWAT;
2064 struct sendfile_stats sf_stats;
2065 struct sendfile_queue *snfq;
2066 clock_t snfq_timeout;
2067 off64_t sendfile_max_size;
2068 
2069 static void snf_enque(snf_req_t *, mblk_t *);
2070 static mblk_t *snf_deque(snf_req_t *);
2071 
2072 void
2073 sendfile_init(void)
2074 {
2075 	snfq = kmem_zalloc(sizeof (struct sendfile_queue), KM_SLEEP);
2076 
2077 	mutex_init(&snfq->snfq_lock, NULL, MUTEX_DEFAULT, NULL);
2078 	cv_init(&snfq->snfq_cv, NULL, CV_DEFAULT, NULL);
2079 	snfq->snfq_max_threads = max_ncpus;
2080 	snfq_timeout = SNFQ_TIMEOUT;
2081 	/* Cache all files by default. */
2082 	sendfile_max_size = MAXOFFSET_T;
2083 }
2084 
2085 /*
2086  * Queues a mblk_t for network processing.
2087  */
2088 static void
2089 snf_enque(snf_req_t *sr, mblk_t *mp)
2090 {
2091 	mp->b_next = NULL;
2092 	mutex_enter(&sr->sr_lock);
2093 	if (sr->sr_mp_head == NULL) {
2094 		sr->sr_mp_head = sr->sr_mp_tail = mp;
2095 		cv_signal(&sr->sr_cv);
2096 	} else {
2097 		sr->sr_mp_tail->b_next = mp;
2098 		sr->sr_mp_tail = mp;
2099 	}
2100 	sr->sr_qlen += MBLKL(mp);
2101 	while ((sr->sr_qlen > sr->sr_hiwat) &&
2102 	    (sr->sr_write_error == 0)) {
2103 		sf_stats.ss_full_waits++;
2104 		cv_wait(&sr->sr_cv, &sr->sr_lock);
2105 	}
2106 	mutex_exit(&sr->sr_lock);
2107 }
2108 
2109 /*
2110  * De-queues a mblk_t for network processing.
2111  */
2112 static mblk_t *
2113 snf_deque(snf_req_t *sr)
2114 {
2115 	mblk_t *mp;
2116 
2117 	mutex_enter(&sr->sr_lock);
2118 	/*
2119 	 * If we have encountered an error on read or read is
2120 	 * completed and no more mblks, return NULL.
2121 	 * We need to check for NULL sr_mp_head also as
2122 	 * the reads could have completed and there is
2123 	 * nothing more to come.
2124 	 */
2125 	if (((sr->sr_read_error & ~SR_READ_DONE) != 0) ||
2126 	    ((sr->sr_read_error & SR_READ_DONE) &&
2127 	    sr->sr_mp_head == NULL)) {
2128 		mutex_exit(&sr->sr_lock);
2129 		return (NULL);
2130 	}
2131 	/*
2132 	 * To start with neither SR_READ_DONE is marked nor
2133 	 * the error is set. When we wake up from cv_wait,
2134 	 * following are the possibilities :
2135 	 *
2136 	 *	a) sr_read_error is zero and mblks are queued.
2137 	 *	b) sr_read_error is set to SR_READ_DONE
2138 	 *	   and mblks are queued.
2139 	 *	c) sr_read_error is set to SR_READ_DONE
2140 	 *	   and no mblks.
2141 	 *	d) sr_read_error is set to some error other
2142 	 *	   than SR_READ_DONE.
2143 	 */
2144 
2145 	while ((sr->sr_read_error == 0) && (sr->sr_mp_head == NULL)) {
2146 		sf_stats.ss_empty_waits++;
2147 		cv_wait(&sr->sr_cv, &sr->sr_lock);
2148 	}
2149 	/* Handle (a) and (b) first  - the normal case. */
2150 	if (((sr->sr_read_error & ~SR_READ_DONE) == 0) &&
2151 	    (sr->sr_mp_head != NULL)) {
2152 		mp = sr->sr_mp_head;
2153 		sr->sr_mp_head = mp->b_next;
2154 		sr->sr_qlen -= MBLKL(mp);
2155 		if (sr->sr_qlen < sr->sr_lowat)
2156 			cv_signal(&sr->sr_cv);
2157 		mutex_exit(&sr->sr_lock);
2158 		mp->b_next = NULL;
2159 		return (mp);
2160 	}
2161 	/* Handle (c) and (d). */
2162 	mutex_exit(&sr->sr_lock);
2163 	return (NULL);
2164 }
2165 
2166 /*
2167  * Reads data from the filesystem and queues it for network processing.
2168  */
2169 void
2170 snf_async_read(snf_req_t *sr)
2171 {
2172 	size_t iosize;
2173 	u_offset_t fileoff;
2174 	u_offset_t size;
2175 	int ret_size;
2176 	int error;
2177 	file_t *fp;
2178 	mblk_t *mp;
2179 	struct vnode *vp;
2180 	int extra = 0;
2181 	int maxblk = 0;
2182 	int wroff = 0;
2183 	struct sonode *so;
2184 
2185 	fp = sr->sr_fp;
2186 	size = sr->sr_file_size;
2187 	fileoff = sr->sr_file_off;
2188 
2189 	/*
2190 	 * Ignore the error for filesystems that doesn't support DIRECTIO.
2191 	 */
2192 	(void) VOP_IOCTL(fp->f_vnode, _FIODIRECTIO, DIRECTIO_ON, 0,
2193 	    kcred, NULL, NULL);
2194 
2195 	vp = sr->sr_vp;
2196 	if (vp->v_type == VSOCK) {
2197 		stdata_t *stp;
2198 
2199 		/*
2200 		 * Get the extra space to insert a header and a trailer.
2201 		 */
2202 		so = VTOSO(vp);
2203 		stp = vp->v_stream;
2204 		if (stp == NULL) {
2205 			wroff = so->so_proto_props.sopp_wroff;
2206 			maxblk = so->so_proto_props.sopp_maxblk;
2207 			extra = wroff + so->so_proto_props.sopp_tail;
2208 		} else {
2209 			wroff = (int)(stp->sd_wroff);
2210 			maxblk = (int)(stp->sd_maxblk);
2211 			extra = wroff + (int)(stp->sd_tail);
2212 		}
2213 	}
2214 
2215 	while ((size != 0) && (sr->sr_write_error == 0)) {
2216 
2217 		iosize = (int)MIN(sr->sr_maxpsz, size);
2218 
2219 		/*
2220 		 * Socket filters can limit the mblk size,
2221 		 * so limit reads to maxblk if there are
2222 		 * filters present.
2223 		 */
2224 		if (vp->v_type == VSOCK &&
2225 		    so->so_filter_active > 0 && maxblk != INFPSZ)
2226 			iosize = (int)MIN(iosize, maxblk);
2227 
2228 		if (is_system_labeled()) {
2229 			mp = allocb_cred(iosize + extra, CRED(),
2230 			    curproc->p_pid);
2231 		} else {
2232 			mp = allocb(iosize + extra, BPRI_MED);
2233 		}
2234 		if (mp == NULL) {
2235 			error = EAGAIN;
2236 			break;
2237 		}
2238 
2239 		mp->b_rptr += wroff;
2240 
2241 		ret_size = soreadfile(fp, mp->b_rptr, fileoff, &error, iosize);
2242 
2243 		/* Error or Reached EOF ? */
2244 		if ((error != 0) || (ret_size == 0)) {
2245 			freeb(mp);
2246 			break;
2247 		}
2248 		mp->b_wptr = mp->b_rptr + ret_size;
2249 
2250 		snf_enque(sr, mp);
2251 		size -= ret_size;
2252 		fileoff += ret_size;
2253 	}
2254 	(void) VOP_IOCTL(fp->f_vnode, _FIODIRECTIO, DIRECTIO_OFF, 0,
2255 	    kcred, NULL, NULL);
2256 	mutex_enter(&sr->sr_lock);
2257 	sr->sr_read_error = error;
2258 	sr->sr_read_error |= SR_READ_DONE;
2259 	cv_signal(&sr->sr_cv);
2260 	mutex_exit(&sr->sr_lock);
2261 }
2262 
2263 void
2264 snf_async_thread(void)
2265 {
2266 	snf_req_t *sr;
2267 	callb_cpr_t cprinfo;
2268 	clock_t time_left = 1;
2269 
2270 	CALLB_CPR_INIT(&cprinfo, &snfq->snfq_lock, callb_generic_cpr, "snfq");
2271 
2272 	mutex_enter(&snfq->snfq_lock);
2273 	for (;;) {
2274 		/*
2275 		 * If we didn't find a entry, then block until woken up
2276 		 * again and then look through the queues again.
2277 		 */
2278 		while ((sr = snfq->snfq_req_head) == NULL) {
2279 			CALLB_CPR_SAFE_BEGIN(&cprinfo);
2280 			if (time_left <= 0) {
2281 				snfq->snfq_svc_threads--;
2282 				CALLB_CPR_EXIT(&cprinfo);
2283 				thread_exit();
2284 				/* NOTREACHED */
2285 			}
2286 			snfq->snfq_idle_cnt++;
2287 
2288 			time_left = cv_reltimedwait(&snfq->snfq_cv,
2289 			    &snfq->snfq_lock, snfq_timeout, TR_CLOCK_TICK);
2290 			snfq->snfq_idle_cnt--;
2291 
2292 			CALLB_CPR_SAFE_END(&cprinfo, &snfq->snfq_lock);
2293 		}
2294 		snfq->snfq_req_head = sr->sr_next;
2295 		snfq->snfq_req_cnt--;
2296 		mutex_exit(&snfq->snfq_lock);
2297 		snf_async_read(sr);
2298 		mutex_enter(&snfq->snfq_lock);
2299 	}
2300 }
2301 
2302 
2303 snf_req_t *
2304 create_thread(int operation, struct vnode *vp, file_t *fp,
2305     u_offset_t fileoff, u_offset_t size)
2306 {
2307 	snf_req_t *sr;
2308 	stdata_t *stp;
2309 
2310 	sr = (snf_req_t *)kmem_zalloc(sizeof (snf_req_t), KM_SLEEP);
2311 
2312 	sr->sr_vp = vp;
2313 	sr->sr_fp = fp;
2314 	stp = vp->v_stream;
2315 
2316 	/*
2317 	 * store sd_qn_maxpsz into sr_maxpsz while we have stream head.
2318 	 * stream might be closed before thread returns from snf_async_read.
2319 	 */
2320 	if (stp != NULL && stp->sd_qn_maxpsz > 0) {
2321 		sr->sr_maxpsz = MIN(MAXBSIZE, stp->sd_qn_maxpsz);
2322 	} else {
2323 		sr->sr_maxpsz = MAXBSIZE;
2324 	}
2325 
2326 	sr->sr_operation = operation;
2327 	sr->sr_file_off = fileoff;
2328 	sr->sr_file_size = size;
2329 	sr->sr_hiwat = sendfile_req_hiwat;
2330 	sr->sr_lowat = sendfile_req_lowat;
2331 	mutex_init(&sr->sr_lock, NULL, MUTEX_DEFAULT, NULL);
2332 	cv_init(&sr->sr_cv, NULL, CV_DEFAULT, NULL);
2333 	/*
2334 	 * See whether we need another thread for servicing this
2335 	 * request. If there are already enough requests queued
2336 	 * for the threads, create one if not exceeding
2337 	 * snfq_max_threads.
2338 	 */
2339 	mutex_enter(&snfq->snfq_lock);
2340 	if (snfq->snfq_req_cnt >= snfq->snfq_idle_cnt &&
2341 	    snfq->snfq_svc_threads < snfq->snfq_max_threads) {
2342 		(void) thread_create(NULL, 0, &snf_async_thread, 0, 0, &p0,
2343 		    TS_RUN, minclsyspri);
2344 		snfq->snfq_svc_threads++;
2345 	}
2346 	if (snfq->snfq_req_head == NULL) {
2347 		snfq->snfq_req_head = snfq->snfq_req_tail = sr;
2348 		cv_signal(&snfq->snfq_cv);
2349 	} else {
2350 		snfq->snfq_req_tail->sr_next = sr;
2351 		snfq->snfq_req_tail = sr;
2352 	}
2353 	snfq->snfq_req_cnt++;
2354 	mutex_exit(&snfq->snfq_lock);
2355 	return (sr);
2356 }
2357 
2358 int
2359 snf_direct_io(file_t *fp, file_t *rfp, u_offset_t fileoff, u_offset_t size,
2360     ssize_t *count)
2361 {
2362 	snf_req_t *sr;
2363 	mblk_t *mp;
2364 	int iosize;
2365 	int error = 0;
2366 	short fflag;
2367 	struct vnode *vp;
2368 	int ksize;
2369 	struct nmsghdr msg;
2370 
2371 	ksize = 0;
2372 	*count = 0;
2373 	bzero(&msg, sizeof (msg));
2374 
2375 	vp = fp->f_vnode;
2376 	fflag = fp->f_flag;
2377 	if ((sr = create_thread(READ_OP, vp, rfp, fileoff, size)) == NULL)
2378 		return (EAGAIN);
2379 
2380 	/*
2381 	 * We check for read error in snf_deque. It has to check
2382 	 * for successful READ_DONE and return NULL, and we might
2383 	 * as well make an additional check there.
2384 	 */
2385 	while ((mp = snf_deque(sr)) != NULL) {
2386 
2387 		if (ISSIG(curthread, JUSTLOOKING)) {
2388 			freeb(mp);
2389 			error = EINTR;
2390 			break;
2391 		}
2392 		iosize = MBLKL(mp);
2393 
2394 		error = socket_sendmblk(VTOSO(vp), &msg, fflag, CRED(), &mp);
2395 
2396 		if (error != 0) {
2397 			if (mp != NULL)
2398 				freeb(mp);
2399 			break;
2400 		}
2401 		ksize += iosize;
2402 	}
2403 	*count = ksize;
2404 
2405 	mutex_enter(&sr->sr_lock);
2406 	sr->sr_write_error = error;
2407 	/* Look at the big comments on why we cv_signal here. */
2408 	cv_signal(&sr->sr_cv);
2409 
2410 	/* Wait for the reader to complete always. */
2411 	while (!(sr->sr_read_error & SR_READ_DONE)) {
2412 		cv_wait(&sr->sr_cv, &sr->sr_lock);
2413 	}
2414 	/* If there is no write error, check for read error. */
2415 	if (error == 0)
2416 		error = (sr->sr_read_error & ~SR_READ_DONE);
2417 
2418 	if (error != 0) {
2419 		mblk_t *next_mp;
2420 
2421 		mp = sr->sr_mp_head;
2422 		while (mp != NULL) {
2423 			next_mp = mp->b_next;
2424 			mp->b_next = NULL;
2425 			freeb(mp);
2426 			mp = next_mp;
2427 		}
2428 	}
2429 	mutex_exit(&sr->sr_lock);
2430 	kmem_free(sr, sizeof (snf_req_t));
2431 	return (error);
2432 }
2433 
2434 /* Maximum no.of pages allocated by vpm for sendfile at a time */
2435 #define	SNF_VPMMAXPGS	(VPMMAXPGS/2)
2436 
2437 /*
2438  * Maximum no.of elements in the list returned by vpm, including
2439  * NULL for the last entry
2440  */
2441 #define	SNF_MAXVMAPS	(SNF_VPMMAXPGS + 1)
2442 
2443 typedef struct {
2444 	unsigned int	snfv_ref;
2445 	frtn_t		snfv_frtn;
2446 	vnode_t		*snfv_vp;
2447 	struct vmap	snfv_vml[SNF_MAXVMAPS];
2448 } snf_vmap_desbinfo;
2449 
2450 typedef struct {
2451 	frtn_t		snfi_frtn;
2452 	caddr_t		snfi_base;
2453 	uint_t		snfi_mapoff;
2454 	size_t		snfi_len;
2455 	vnode_t		*snfi_vp;
2456 } snf_smap_desbinfo;
2457 
2458 /*
2459  * The callback function used for vpm mapped mblks called when the last ref of
2460  * the mblk is dropped which normally occurs when TCP receives the ack. But it
2461  * can be the driver too due to lazy reclaim.
2462  */
2463 void
2464 snf_vmap_desbfree(snf_vmap_desbinfo *snfv)
2465 {
2466 	ASSERT(snfv->snfv_ref != 0);
2467 	if (atomic_dec_32_nv(&snfv->snfv_ref) == 0) {
2468 		vpm_unmap_pages(snfv->snfv_vml, S_READ);
2469 		VN_RELE(snfv->snfv_vp);
2470 		kmem_free(snfv, sizeof (snf_vmap_desbinfo));
2471 	}
2472 }
2473 
2474 /*
2475  * The callback function used for segmap'ped mblks called when the last ref of
2476  * the mblk is dropped which normally occurs when TCP receives the ack. But it
2477  * can be the driver too due to lazy reclaim.
2478  */
2479 void
2480 snf_smap_desbfree(snf_smap_desbinfo *snfi)
2481 {
2482 	if (! IS_KPM_ADDR(snfi->snfi_base)) {
2483 		/*
2484 		 * We don't need to call segmap_fault(F_SOFTUNLOCK) for
2485 		 * segmap_kpm as long as the latter never falls back to
2486 		 * "use_segmap_range". (See segmap_getmapflt().)
2487 		 *
2488 		 * Using S_OTHER saves an redundant hat_setref() in
2489 		 * segmap_unlock()
2490 		 */
2491 		(void) segmap_fault(kas.a_hat, segkmap,
2492 		    (caddr_t)(uintptr_t)(((uintptr_t)snfi->snfi_base +
2493 		    snfi->snfi_mapoff) & PAGEMASK), snfi->snfi_len,
2494 		    F_SOFTUNLOCK, S_OTHER);
2495 	}
2496 	(void) segmap_release(segkmap, snfi->snfi_base, SM_DONTNEED);
2497 	VN_RELE(snfi->snfi_vp);
2498 	kmem_free(snfi, sizeof (*snfi));
2499 }
2500 
2501 /*
2502  * Use segmap or vpm instead of bcopy to send down a desballoca'ed, mblk.
2503  * When segmap is used, the mblk contains a segmap slot of no more
2504  * than MAXBSIZE.
2505  *
2506  * With vpm, a maximum of SNF_MAXVMAPS page-sized mappings can be obtained
2507  * in each iteration and sent by socket_sendmblk until an error occurs or
2508  * the requested size has been transferred. An mblk is esballoca'ed from
2509  * each mapped page and a chain of these mblk is sent to the transport layer.
2510  * vpm will be called to unmap the pages when all mblks have been freed by
2511  * free_func.
2512  *
2513  * At the end of the whole sendfile() operation, we wait till the data from
2514  * the last mblk is ack'ed by the transport before returning so that the
2515  * caller of sendfile() can safely modify the file content.
2516  *
2517  * The caller of this function should make sure that total_size does not exceed
2518  * the actual file size of fvp.
2519  */
2520 int
2521 snf_segmap(file_t *fp, vnode_t *fvp, u_offset_t fileoff, u_offset_t total_size,
2522     ssize_t *count, boolean_t nowait)
2523 {
2524 	caddr_t base;
2525 	int mapoff;
2526 	vnode_t *vp;
2527 	mblk_t *mp = NULL;
2528 	int chain_size;
2529 	int error;
2530 	clock_t deadlk_wait;
2531 	short fflag;
2532 	int ksize;
2533 	struct vattr va;
2534 	boolean_t dowait = B_FALSE;
2535 	struct nmsghdr msg;
2536 
2537 	vp = fp->f_vnode;
2538 	fflag = fp->f_flag;
2539 	ksize = 0;
2540 	bzero(&msg, sizeof (msg));
2541 
2542 	for (;;) {
2543 		if (ISSIG(curthread, JUSTLOOKING)) {
2544 			error = EINTR;
2545 			break;
2546 		}
2547 
2548 		if (vpm_enable) {
2549 			snf_vmap_desbinfo *snfv;
2550 			mblk_t *nmp;
2551 			int mblk_size;
2552 			int maxsize;
2553 			int i;
2554 
2555 			mapoff = fileoff & PAGEOFFSET;
2556 			maxsize = MIN((SNF_VPMMAXPGS * PAGESIZE), total_size);
2557 
2558 			snfv = kmem_zalloc(sizeof (snf_vmap_desbinfo),
2559 			    KM_SLEEP);
2560 
2561 			/*
2562 			 * Get vpm mappings for maxsize with read access.
2563 			 * If the pages aren't available yet, we get
2564 			 * DEADLK, so wait and try again a little later using
2565 			 * an increasing wait. We might be here a long time.
2566 			 *
2567 			 * If delay_sig returns EINTR, be sure to exit and
2568 			 * pass it up to the caller.
2569 			 */
2570 			deadlk_wait = 0;
2571 			while ((error = vpm_map_pages(fvp, fileoff,
2572 			    (size_t)maxsize, (VPM_FETCHPAGE), snfv->snfv_vml,
2573 			    SNF_MAXVMAPS, NULL, S_READ)) == EDEADLK) {
2574 				deadlk_wait += (deadlk_wait < 5) ? 1 : 4;
2575 				if ((error = delay_sig(deadlk_wait)) != 0) {
2576 					break;
2577 				}
2578 			}
2579 			if (error != 0) {
2580 				kmem_free(snfv, sizeof (snf_vmap_desbinfo));
2581 				error = (error == EINTR) ? EINTR : EIO;
2582 				goto out;
2583 			}
2584 			snfv->snfv_frtn.free_func = snf_vmap_desbfree;
2585 			snfv->snfv_frtn.free_arg = (caddr_t)snfv;
2586 
2587 			/* Construct the mblk chain from the page mappings */
2588 			chain_size = 0;
2589 			for (i = 0; (snfv->snfv_vml[i].vs_addr != NULL) &&
2590 			    total_size > 0; i++) {
2591 				ASSERT(chain_size < maxsize);
2592 				mblk_size = MIN(snfv->snfv_vml[i].vs_len -
2593 				    mapoff, total_size);
2594 				nmp = esballoca(
2595 				    (uchar_t *)snfv->snfv_vml[i].vs_addr +
2596 				    mapoff, mblk_size, BPRI_HI,
2597 				    &snfv->snfv_frtn);
2598 
2599 				/*
2600 				 * We return EAGAIN after unmapping the pages
2601 				 * if we cannot allocate the the head of the
2602 				 * chain. Otherwise, we continue sending the
2603 				 * mblks constructed so far.
2604 				 */
2605 				if (nmp == NULL) {
2606 					if (i == 0) {
2607 						vpm_unmap_pages(snfv->snfv_vml,
2608 						    S_READ);
2609 						kmem_free(snfv,
2610 						    sizeof (snf_vmap_desbinfo));
2611 						error = EAGAIN;
2612 						goto out;
2613 					}
2614 					break;
2615 				}
2616 				/* Mark this dblk with the zero-copy flag */
2617 				nmp->b_datap->db_struioflag |= STRUIO_ZC;
2618 				nmp->b_wptr += mblk_size;
2619 				chain_size += mblk_size;
2620 				fileoff += mblk_size;
2621 				total_size -= mblk_size;
2622 				snfv->snfv_ref++;
2623 				mapoff = 0;
2624 				if (i > 0)
2625 					linkb(mp, nmp);
2626 				else
2627 					mp = nmp;
2628 			}
2629 			VN_HOLD(fvp);
2630 			snfv->snfv_vp = fvp;
2631 		} else {
2632 			/* vpm not supported. fallback to segmap */
2633 			snf_smap_desbinfo *snfi;
2634 
2635 			mapoff = fileoff & MAXBOFFSET;
2636 			chain_size = MAXBSIZE - mapoff;
2637 			if (chain_size > total_size)
2638 				chain_size = total_size;
2639 			/*
2640 			 * we don't forcefault because we'll call
2641 			 * segmap_fault(F_SOFTLOCK) next.
2642 			 *
2643 			 * S_READ will get the ref bit set (by either
2644 			 * segmap_getmapflt() or segmap_fault()) and page
2645 			 * shared locked.
2646 			 */
2647 			base = segmap_getmapflt(segkmap, fvp, fileoff,
2648 			    chain_size, segmap_kpm ? SM_FAULT : 0, S_READ);
2649 
2650 			snfi = kmem_alloc(sizeof (*snfi), KM_SLEEP);
2651 			snfi->snfi_len = (size_t)roundup(mapoff+chain_size,
2652 			    PAGESIZE)- (mapoff & PAGEMASK);
2653 			/*
2654 			 * We must call segmap_fault() even for segmap_kpm
2655 			 * because that's how error gets returned.
2656 			 * (segmap_getmapflt() never fails but segmap_fault()
2657 			 * does.)
2658 			 *
2659 			 * If the pages aren't available yet, we get
2660 			 * DEADLK, so wait and try again a little later using
2661 			 * an increasing wait. We might be here a long time.
2662 			 *
2663 			 * If delay_sig returns EINTR, be sure to exit and
2664 			 * pass it up to the caller.
2665 			 */
2666 			deadlk_wait = 0;
2667 			while ((error = FC_ERRNO(segmap_fault(kas.a_hat,
2668 			    segkmap, (caddr_t)(uintptr_t)(((uintptr_t)base +
2669 			    mapoff) & PAGEMASK), snfi->snfi_len, F_SOFTLOCK,
2670 			    S_READ))) == EDEADLK) {
2671 				deadlk_wait += (deadlk_wait < 5) ? 1 : 4;
2672 				if ((error = delay_sig(deadlk_wait)) != 0) {
2673 					break;
2674 				}
2675 			}
2676 			if (error != 0) {
2677 				(void) segmap_release(segkmap, base, 0);
2678 				kmem_free(snfi, sizeof (*snfi));
2679 				error = (error == EINTR) ? EINTR : EIO;
2680 				goto out;
2681 			}
2682 			snfi->snfi_frtn.free_func = snf_smap_desbfree;
2683 			snfi->snfi_frtn.free_arg = (caddr_t)snfi;
2684 			snfi->snfi_base = base;
2685 			snfi->snfi_mapoff = mapoff;
2686 			mp = esballoca((uchar_t *)base + mapoff, chain_size,
2687 			    BPRI_HI, &snfi->snfi_frtn);
2688 
2689 			if (mp == NULL) {
2690 				(void) segmap_fault(kas.a_hat, segkmap,
2691 				    (caddr_t)(uintptr_t)(((uintptr_t)base +
2692 				    mapoff) & PAGEMASK), snfi->snfi_len,
2693 				    F_SOFTUNLOCK, S_OTHER);
2694 				(void) segmap_release(segkmap, base, 0);
2695 				kmem_free(snfi, sizeof (*snfi));
2696 				freemsg(mp);
2697 				error = EAGAIN;
2698 				goto out;
2699 			}
2700 			VN_HOLD(fvp);
2701 			snfi->snfi_vp = fvp;
2702 			mp->b_wptr += chain_size;
2703 
2704 			/* Mark this dblk with the zero-copy flag */
2705 			mp->b_datap->db_struioflag |= STRUIO_ZC;
2706 			fileoff += chain_size;
2707 			total_size -= chain_size;
2708 		}
2709 
2710 		if (total_size == 0 && !nowait) {
2711 			ASSERT(!dowait);
2712 			dowait = B_TRUE;
2713 			mp->b_datap->db_struioflag |= STRUIO_ZCNOTIFY;
2714 		}
2715 		VOP_RWUNLOCK(fvp, V_WRITELOCK_FALSE, NULL);
2716 		error = socket_sendmblk(VTOSO(vp), &msg, fflag, CRED(), &mp);
2717 		if (error != 0) {
2718 			/*
2719 			 * mp contains the mblks that were not sent by
2720 			 * socket_sendmblk. Use its size to update *count
2721 			 */
2722 			*count = ksize + (chain_size - msgdsize(mp));
2723 			if (mp != NULL)
2724 				freemsg(mp);
2725 			return (error);
2726 		}
2727 		ksize += chain_size;
2728 		if (total_size == 0)
2729 			goto done;
2730 
2731 		(void) VOP_RWLOCK(fvp, V_WRITELOCK_FALSE, NULL);
2732 		va.va_mask = AT_SIZE;
2733 		error = VOP_GETATTR(fvp, &va, 0, kcred, NULL);
2734 		if (error)
2735 			break;
2736 		/* Read as much as possible. */
2737 		if (fileoff >= va.va_size)
2738 			break;
2739 		if (total_size + fileoff > va.va_size)
2740 			total_size = va.va_size - fileoff;
2741 	}
2742 out:
2743 	VOP_RWUNLOCK(fvp, V_WRITELOCK_FALSE, NULL);
2744 done:
2745 	*count = ksize;
2746 	if (dowait) {
2747 		stdata_t *stp;
2748 
2749 		stp = vp->v_stream;
2750 		if (stp == NULL) {
2751 			struct sonode *so;
2752 			so = VTOSO(vp);
2753 			error = so_zcopy_wait(so);
2754 		} else {
2755 			mutex_enter(&stp->sd_lock);
2756 			while (!(stp->sd_flag & STZCNOTIFY)) {
2757 				if (cv_wait_sig(&stp->sd_zcopy_wait,
2758 				    &stp->sd_lock) == 0) {
2759 					error = EINTR;
2760 					break;
2761 				}
2762 			}
2763 			stp->sd_flag &= ~STZCNOTIFY;
2764 			mutex_exit(&stp->sd_lock);
2765 		}
2766 	}
2767 	return (error);
2768 }
2769 
2770 int
2771 snf_cache(file_t *fp, vnode_t *fvp, u_offset_t fileoff, u_offset_t size,
2772     uint_t maxpsz, ssize_t *count)
2773 {
2774 	struct vnode *vp;
2775 	mblk_t *mp;
2776 	int iosize;
2777 	int extra = 0;
2778 	int error;
2779 	short fflag;
2780 	int ksize;
2781 	int ioflag;
2782 	struct uio auio;
2783 	struct iovec aiov;
2784 	struct vattr va;
2785 	int maxblk = 0;
2786 	int wroff = 0;
2787 	struct sonode *so;
2788 	struct nmsghdr msg;
2789 
2790 	vp = fp->f_vnode;
2791 	if (vp->v_type == VSOCK) {
2792 		stdata_t *stp;
2793 
2794 		/*
2795 		 * Get the extra space to insert a header and a trailer.
2796 		 */
2797 		so = VTOSO(vp);
2798 		stp = vp->v_stream;
2799 		if (stp == NULL) {
2800 			wroff = so->so_proto_props.sopp_wroff;
2801 			maxblk = so->so_proto_props.sopp_maxblk;
2802 			extra = wroff + so->so_proto_props.sopp_tail;
2803 		} else {
2804 			wroff = (int)(stp->sd_wroff);
2805 			maxblk = (int)(stp->sd_maxblk);
2806 			extra = wroff + (int)(stp->sd_tail);
2807 		}
2808 	}
2809 	bzero(&msg, sizeof (msg));
2810 	fflag = fp->f_flag;
2811 	ksize = 0;
2812 	auio.uio_iov = &aiov;
2813 	auio.uio_iovcnt = 1;
2814 	auio.uio_segflg = UIO_SYSSPACE;
2815 	auio.uio_llimit = MAXOFFSET_T;
2816 	auio.uio_fmode = fflag;
2817 	auio.uio_extflg = UIO_COPY_CACHED;
2818 	ioflag = auio.uio_fmode & (FSYNC|FDSYNC|FRSYNC);
2819 	/* If read sync is not asked for, filter sync flags */
2820 	if ((ioflag & FRSYNC) == 0)
2821 		ioflag &= ~(FSYNC|FDSYNC);
2822 	for (;;) {
2823 		if (ISSIG(curthread, JUSTLOOKING)) {
2824 			error = EINTR;
2825 			break;
2826 		}
2827 		iosize = (int)MIN(maxpsz, size);
2828 
2829 		/*
2830 		 * Socket filters can limit the mblk size,
2831 		 * so limit reads to maxblk if there are
2832 		 * filters present.
2833 		 */
2834 		if (vp->v_type == VSOCK &&
2835 		    so->so_filter_active > 0 && maxblk != INFPSZ)
2836 			iosize = (int)MIN(iosize, maxblk);
2837 
2838 		if (is_system_labeled()) {
2839 			mp = allocb_cred(iosize + extra, CRED(),
2840 			    curproc->p_pid);
2841 		} else {
2842 			mp = allocb(iosize + extra, BPRI_MED);
2843 		}
2844 		if (mp == NULL) {
2845 			error = EAGAIN;
2846 			break;
2847 		}
2848 
2849 		mp->b_rptr += wroff;
2850 
2851 		aiov.iov_base = (caddr_t)mp->b_rptr;
2852 		aiov.iov_len = iosize;
2853 		auio.uio_loffset = fileoff;
2854 		auio.uio_resid = iosize;
2855 
2856 		error = VOP_READ(fvp, &auio, ioflag, fp->f_cred, NULL);
2857 		iosize -= auio.uio_resid;
2858 
2859 		if (error == EINTR && iosize != 0)
2860 			error = 0;
2861 
2862 		if (error != 0 || iosize == 0) {
2863 			freeb(mp);
2864 			break;
2865 		}
2866 		mp->b_wptr = mp->b_rptr + iosize;
2867 
2868 		VOP_RWUNLOCK(fvp, V_WRITELOCK_FALSE, NULL);
2869 
2870 		error = socket_sendmblk(VTOSO(vp), &msg, fflag, CRED(), &mp);
2871 
2872 		if (error != 0) {
2873 			*count = ksize;
2874 			if (mp != NULL)
2875 				freeb(mp);
2876 			return (error);
2877 		}
2878 		ksize += iosize;
2879 		size -= iosize;
2880 		if (size == 0)
2881 			goto done;
2882 
2883 		fileoff += iosize;
2884 		(void) VOP_RWLOCK(fvp, V_WRITELOCK_FALSE, NULL);
2885 		va.va_mask = AT_SIZE;
2886 		error = VOP_GETATTR(fvp, &va, 0, kcred, NULL);
2887 		if (error)
2888 			break;
2889 		/* Read as much as possible. */
2890 		if (fileoff >= va.va_size)
2891 			size = 0;
2892 		else if (size + fileoff > va.va_size)
2893 			size = va.va_size - fileoff;
2894 	}
2895 	VOP_RWUNLOCK(fvp, V_WRITELOCK_FALSE, NULL);
2896 done:
2897 	*count = ksize;
2898 	return (error);
2899 }
2900 
2901 #if defined(_SYSCALL32_IMPL) || defined(_ILP32)
2902 /*
2903  * Largefile support for 32 bit applications only.
2904  */
2905 int
2906 sosendfile64(file_t *fp, file_t *rfp, const struct ksendfilevec64 *sfv,
2907     ssize32_t *count32)
2908 {
2909 	ssize32_t sfv_len;
2910 	u_offset_t sfv_off, va_size;
2911 	struct vnode *vp, *fvp, *realvp;
2912 	struct vattr va;
2913 	stdata_t *stp;
2914 	ssize_t count = 0;
2915 	int error = 0;
2916 	boolean_t dozcopy = B_FALSE;
2917 	uint_t maxpsz;
2918 
2919 	sfv_len = (ssize32_t)sfv->sfv_len;
2920 	if (sfv_len < 0) {
2921 		error = EINVAL;
2922 		goto out;
2923 	}
2924 
2925 	if (sfv_len == 0) goto out;
2926 
2927 	sfv_off = (u_offset_t)sfv->sfv_off;
2928 
2929 	/* Same checks as in pread */
2930 	if (sfv_off > MAXOFFSET_T) {
2931 		error = EINVAL;
2932 		goto out;
2933 	}
2934 	if (sfv_off + sfv_len > MAXOFFSET_T)
2935 		sfv_len = (ssize32_t)(MAXOFFSET_T - sfv_off);
2936 
2937 	/*
2938 	 * There are no more checks on sfv_len. So, we cast it to
2939 	 * u_offset_t and share the snf_direct_io/snf_cache code between
2940 	 * 32 bit and 64 bit.
2941 	 *
2942 	 * TODO: should do nbl_need_check() like read()?
2943 	 */
2944 	if (sfv_len > sendfile_max_size) {
2945 		sf_stats.ss_file_not_cached++;
2946 		error = snf_direct_io(fp, rfp, sfv_off, (u_offset_t)sfv_len,
2947 		    &count);
2948 		goto out;
2949 	}
2950 	fvp = rfp->f_vnode;
2951 	if (VOP_REALVP(fvp, &realvp, NULL) == 0)
2952 		fvp = realvp;
2953 	/*
2954 	 * Grab the lock as a reader to prevent the file size
2955 	 * from changing underneath.
2956 	 */
2957 	(void) VOP_RWLOCK(fvp, V_WRITELOCK_FALSE, NULL);
2958 	va.va_mask = AT_SIZE;
2959 	error = VOP_GETATTR(fvp, &va, 0, kcred, NULL);
2960 	va_size = va.va_size;
2961 	if ((error != 0) || (va_size == 0) || (sfv_off >= va_size)) {
2962 		VOP_RWUNLOCK(fvp, V_WRITELOCK_FALSE, NULL);
2963 		goto out;
2964 	}
2965 	/* Read as much as possible. */
2966 	if (sfv_off + sfv_len > va_size)
2967 		sfv_len = va_size - sfv_off;
2968 
2969 	vp = fp->f_vnode;
2970 	stp = vp->v_stream;
2971 	/*
2972 	 * When the NOWAIT flag is not set, we enable zero-copy only if the
2973 	 * transfer size is large enough. This prevents performance loss
2974 	 * when the caller sends the file piece by piece.
2975 	 */
2976 	if (sfv_len >= MAXBSIZE && (sfv_len >= (va_size >> 1) ||
2977 	    (sfv->sfv_flag & SFV_NOWAIT) || sfv_len >= 0x1000000) &&
2978 	    !vn_has_flocks(fvp) && !(fvp->v_flag & VNOMAP)) {
2979 		uint_t copyflag;
2980 		copyflag = stp != NULL ? stp->sd_copyflag :
2981 		    VTOSO(vp)->so_proto_props.sopp_zcopyflag;
2982 		if ((copyflag & (STZCVMSAFE|STZCVMUNSAFE)) == 0) {
2983 			int on = 1;
2984 
2985 			if (socket_setsockopt(VTOSO(vp), SOL_SOCKET,
2986 			    SO_SND_COPYAVOID, &on, sizeof (on), CRED()) == 0)
2987 				dozcopy = B_TRUE;
2988 		} else {
2989 			dozcopy = copyflag & STZCVMSAFE;
2990 		}
2991 	}
2992 	if (dozcopy) {
2993 		sf_stats.ss_file_segmap++;
2994 		error = snf_segmap(fp, fvp, sfv_off, (u_offset_t)sfv_len,
2995 		    &count, ((sfv->sfv_flag & SFV_NOWAIT) != 0));
2996 	} else {
2997 		if (vp->v_type == VSOCK && stp == NULL) {
2998 			sonode_t *so = VTOSO(vp);
2999 			maxpsz = so->so_proto_props.sopp_maxpsz;
3000 		} else if (stp != NULL) {
3001 			maxpsz = stp->sd_qn_maxpsz;
3002 		} else {
3003 			maxpsz = maxphys;
3004 		}
3005 
3006 		if (maxpsz == INFPSZ)
3007 			maxpsz = maxphys;
3008 		else
3009 			maxpsz = roundup(maxpsz, MAXBSIZE);
3010 		sf_stats.ss_file_cached++;
3011 		error = snf_cache(fp, fvp, sfv_off, (u_offset_t)sfv_len,
3012 		    maxpsz, &count);
3013 	}
3014 out:
3015 	releasef(sfv->sfv_fd);
3016 	*count32 = (ssize32_t)count;
3017 	return (error);
3018 }
3019 #endif
3020 
3021 #ifdef _SYSCALL32_IMPL
3022 /*
3023  * recv32(), recvfrom32(), send32(), sendto32(): intentionally return a
3024  * ssize_t rather than ssize32_t; see the comments above read32 for details.
3025  */
3026 
3027 ssize_t
3028 recv32(int32_t sock, caddr32_t buffer, size32_t len, int32_t flags)
3029 {
3030 	return (recv(sock, (void *)(uintptr_t)buffer, (ssize32_t)len, flags));
3031 }
3032 
3033 ssize_t
3034 recvfrom32(int32_t sock, caddr32_t buffer, size32_t len, int32_t flags,
3035     caddr32_t name, caddr32_t namelenp)
3036 {
3037 	return (recvfrom(sock, (void *)(uintptr_t)buffer, (ssize32_t)len, flags,
3038 	    (void *)(uintptr_t)name, (void *)(uintptr_t)namelenp));
3039 }
3040 
3041 ssize_t
3042 send32(int32_t sock, caddr32_t buffer, size32_t len, int32_t flags)
3043 {
3044 	return (send(sock, (void *)(uintptr_t)buffer, (ssize32_t)len, flags));
3045 }
3046 
3047 ssize_t
3048 sendto32(int32_t sock, caddr32_t buffer, size32_t len, int32_t flags,
3049     caddr32_t name, socklen_t namelen)
3050 {
3051 	return (sendto(sock, (void *)(uintptr_t)buffer, (ssize32_t)len, flags,
3052 	    (void *)(uintptr_t)name, namelen));
3053 }
3054 #endif	/* _SYSCALL32_IMPL */
3055 
3056 /*
3057  * Function wrappers (mostly around the sonode switch) for
3058  * backward compatibility.
3059  */
3060 
3061 int
3062 soaccept(struct sonode *so, int fflag, struct sonode **nsop)
3063 {
3064 	return (socket_accept(so, fflag, CRED(), nsop));
3065 }
3066 
3067 int
3068 sobind(struct sonode *so, struct sockaddr *name, socklen_t namelen,
3069     int backlog, int flags)
3070 {
3071 	int	error;
3072 
3073 	error = socket_bind(so, name, namelen, flags, CRED());
3074 	if (error == 0 && backlog != 0)
3075 		return (socket_listen(so, backlog, CRED()));
3076 
3077 	return (error);
3078 }
3079 
3080 int
3081 solisten(struct sonode *so, int backlog)
3082 {
3083 	return (socket_listen(so, backlog, CRED()));
3084 }
3085 
3086 int
3087 soconnect(struct sonode *so, struct sockaddr *name, socklen_t namelen,
3088     int fflag, int flags)
3089 {
3090 	return (socket_connect(so, name, namelen, fflag, flags, CRED()));
3091 }
3092 
3093 int
3094 sorecvmsg(struct sonode *so, struct nmsghdr *msg, struct uio *uiop)
3095 {
3096 	return (socket_recvmsg(so, msg, uiop, CRED()));
3097 }
3098 
3099 int
3100 sosendmsg(struct sonode *so, struct nmsghdr *msg, struct uio *uiop)
3101 {
3102 	return (socket_sendmsg(so, msg, uiop, CRED()));
3103 }
3104 
3105 int
3106 soshutdown(struct sonode *so, int how)
3107 {
3108 	return (socket_shutdown(so, how, CRED()));
3109 }
3110 
3111 int
3112 sogetsockopt(struct sonode *so, int level, int option_name, void *optval,
3113     socklen_t *optlenp, int flags)
3114 {
3115 	return (socket_getsockopt(so, level, option_name, optval, optlenp,
3116 	    flags, CRED()));
3117 }
3118 
3119 int
3120 sosetsockopt(struct sonode *so, int level, int option_name, const void *optval,
3121     t_uscalar_t optlen)
3122 {
3123 	return (socket_setsockopt(so, level, option_name, optval, optlen,
3124 	    CRED()));
3125 }
3126 
3127 /*
3128  * Because this is backward compatibility interface it only needs to be
3129  * able to handle the creation of TPI sockfs sockets.
3130  */
3131 struct sonode *
3132 socreate(struct sockparams *sp, int family, int type, int protocol, int version,
3133     int *errorp)
3134 {
3135 	struct sonode *so;
3136 
3137 	ASSERT(sp != NULL);
3138 
3139 	so = sp->sp_smod_info->smod_sock_create_func(sp, family, type, protocol,
3140 	    version, SOCKET_SLEEP, errorp, CRED());
3141 	if (so == NULL) {
3142 		SOCKPARAMS_DEC_REF(sp);
3143 	} else {
3144 		if ((*errorp = SOP_INIT(so, NULL, CRED(), SOCKET_SLEEP)) == 0) {
3145 			/* Cannot fail, only bumps so_count */
3146 			(void) VOP_OPEN(&SOTOV(so), FREAD|FWRITE, CRED(), NULL);
3147 		} else {
3148 			socket_destroy(so);
3149 			so = NULL;
3150 		}
3151 	}
3152 	return (so);
3153 }
3154