xref: /dragonfly/sys/vfs/nfs/nfs_socket.c (revision 3170ffd7)
1 /*
2  * Copyright (c) 1989, 1991, 1993, 1995
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * This code is derived from software contributed to Berkeley by
6  * Rick Macklem at The University of Guelph.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 4. Neither the name of the University nor the names of its contributors
17  *    may be used to endorse or promote products derived from this software
18  *    without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30  * SUCH DAMAGE.
31  *
32  *	@(#)nfs_socket.c	8.5 (Berkeley) 3/30/95
33  * $FreeBSD: src/sys/nfs/nfs_socket.c,v 1.60.2.6 2003/03/26 01:44:46 alfred Exp $
34  */
35 
36 /*
37  * Socket operations for use by nfs
38  */
39 
40 #include <sys/param.h>
41 #include <sys/systm.h>
42 #include <sys/proc.h>
43 #include <sys/malloc.h>
44 #include <sys/mount.h>
45 #include <sys/kernel.h>
46 #include <sys/mbuf.h>
47 #include <sys/vnode.h>
48 #include <sys/fcntl.h>
49 #include <sys/protosw.h>
50 #include <sys/resourcevar.h>
51 #include <sys/socket.h>
52 #include <sys/socketvar.h>
53 #include <sys/socketops.h>
54 #include <sys/syslog.h>
55 #include <sys/thread.h>
56 #include <sys/tprintf.h>
57 #include <sys/sysctl.h>
58 #include <sys/signalvar.h>
59 
60 #include <sys/signal2.h>
61 #include <sys/mutex2.h>
62 #include <sys/socketvar2.h>
63 
64 #include <netinet/in.h>
65 #include <netinet/tcp.h>
66 #include <sys/thread2.h>
67 
68 #include "rpcv2.h"
69 #include "nfsproto.h"
70 #include "nfs.h"
71 #include "xdr_subs.h"
72 #include "nfsm_subs.h"
73 #include "nfsmount.h"
74 #include "nfsnode.h"
75 #include "nfsrtt.h"
76 
77 #define	TRUE	1
78 #define	FALSE	0
79 
80 /*
81  * RTT calculations are scaled by 256 (8 bits).  A proper fractional
82  * RTT will still be calculated even with a slow NFS timer.
83  */
84 #define	NFS_SRTT(r)	(r)->r_nmp->nm_srtt[proct[(r)->r_procnum]]
85 #define	NFS_SDRTT(r)	(r)->r_nmp->nm_sdrtt[proct[(r)->r_procnum]]
86 #define NFS_RTT_SCALE_BITS	8	/* bits */
87 #define NFS_RTT_SCALE		256	/* value */
88 
89 /*
90  * Defines which timer to use for the procnum.
91  * 0 - default
92  * 1 - getattr
93  * 2 - lookup
94  * 3 - read
95  * 4 - write
96  */
97 static int proct[NFS_NPROCS] = {
98 	0, 1, 0, 2, 1, 3, 3, 4, 0, 0,	/* 00-09	*/
99 	0, 0, 0, 0, 0, 0, 3, 3, 0, 0,	/* 10-19	*/
100 	0, 5, 0, 0, 0, 0,		/* 20-29	*/
101 };
102 
103 static int multt[NFS_NPROCS] = {
104 	1, 1, 1, 1, 1, 1, 1, 1, 1, 1,	/* 00-09	*/
105 	1, 1, 1, 1, 1, 1, 1, 1, 1, 1,	/* 10-19	*/
106 	1, 2, 1, 1, 1, 1,		/* 20-29	*/
107 };
108 
109 static int nfs_backoff[8] = { 2, 3, 5, 8, 13, 21, 34, 55 };
110 static int nfs_realign_test;
111 static int nfs_realign_count;
112 static int nfs_showrtt;
113 static int nfs_showrexmit;
114 int nfs_maxasyncbio = NFS_MAXASYNCBIO;
115 
116 SYSCTL_DECL(_vfs_nfs);
117 
118 SYSCTL_INT(_vfs_nfs, OID_AUTO, realign_test, CTLFLAG_RW, &nfs_realign_test, 0,
119     "Number of times mbufs have been tested for bad alignment");
120 SYSCTL_INT(_vfs_nfs, OID_AUTO, realign_count, CTLFLAG_RW, &nfs_realign_count, 0,
121     "Number of realignments for badly aligned mbuf data");
122 SYSCTL_INT(_vfs_nfs, OID_AUTO, showrtt, CTLFLAG_RW, &nfs_showrtt, 0,
123     "Show round trip time output");
124 SYSCTL_INT(_vfs_nfs, OID_AUTO, showrexmit, CTLFLAG_RW, &nfs_showrexmit, 0,
125     "Show retransmits info");
126 SYSCTL_INT(_vfs_nfs, OID_AUTO, maxasyncbio, CTLFLAG_RW, &nfs_maxasyncbio, 0,
127     "Max number of asynchronous bio's");
128 
129 static int nfs_request_setup(nfsm_info_t info);
130 static int nfs_request_auth(struct nfsreq *rep);
131 static int nfs_request_try(struct nfsreq *rep);
132 static int nfs_request_waitreply(struct nfsreq *rep);
133 static int nfs_request_processreply(nfsm_info_t info, int);
134 
135 int nfsrtton = 0;
136 struct nfsrtt nfsrtt;
137 struct callout	nfs_timer_handle;
138 
139 static int	nfs_msg (struct thread *,char *,char *);
140 static int	nfs_rcvlock (struct nfsmount *nmp, struct nfsreq *myreq);
141 static void	nfs_rcvunlock (struct nfsmount *nmp);
142 static void	nfs_realign (struct mbuf **pm, int hsiz);
143 static int	nfs_receive (struct nfsmount *nmp, struct nfsreq *rep,
144 				struct sockaddr **aname, struct mbuf **mp);
145 static void	nfs_softterm (struct nfsreq *rep, int islocked);
146 static void	nfs_hardterm (struct nfsreq *rep, int islocked);
147 static int	nfs_reconnect (struct nfsmount *nmp, struct nfsreq *rep);
148 #ifndef NFS_NOSERVER
149 static int	nfsrv_getstream (struct nfssvc_sock *, int, int *);
150 static void	nfs_timer_req(struct nfsreq *req);
151 static void	nfs_checkpkt(struct mbuf *m, int len);
152 
153 int (*nfsrv3_procs[NFS_NPROCS]) (struct nfsrv_descript *nd,
154 				    struct nfssvc_sock *slp,
155 				    struct thread *td,
156 				    struct mbuf **mreqp) = {
157 	nfsrv_null,
158 	nfsrv_getattr,
159 	nfsrv_setattr,
160 	nfsrv_lookup,
161 	nfsrv3_access,
162 	nfsrv_readlink,
163 	nfsrv_read,
164 	nfsrv_write,
165 	nfsrv_create,
166 	nfsrv_mkdir,
167 	nfsrv_symlink,
168 	nfsrv_mknod,
169 	nfsrv_remove,
170 	nfsrv_rmdir,
171 	nfsrv_rename,
172 	nfsrv_link,
173 	nfsrv_readdir,
174 	nfsrv_readdirplus,
175 	nfsrv_statfs,
176 	nfsrv_fsinfo,
177 	nfsrv_pathconf,
178 	nfsrv_commit,
179 	nfsrv_noop,
180 	nfsrv_noop,
181 	nfsrv_noop,
182 	nfsrv_noop
183 };
184 #endif /* NFS_NOSERVER */
185 
186 /*
187  * Initialize sockets and congestion for a new NFS connection.
188  * We do not free the sockaddr if error.
189  */
190 int
191 nfs_connect(struct nfsmount *nmp, struct nfsreq *rep)
192 {
193 	struct socket *so;
194 	int error;
195 	struct sockaddr *saddr;
196 	struct sockaddr_in *sin;
197 	struct thread *td = &thread0; /* only used for socreate and sobind */
198 
199 	nmp->nm_so = so = NULL;
200 	if (nmp->nm_flag & NFSMNT_FORCE)
201 		return (EINVAL);
202 	saddr = nmp->nm_nam;
203 	error = socreate(saddr->sa_family, &so, nmp->nm_sotype,
204 		nmp->nm_soproto, td);
205 	if (error)
206 		goto bad;
207 	nmp->nm_soflags = so->so_proto->pr_flags;
208 
209 	/*
210 	 * Some servers require that the client port be a reserved port number.
211 	 */
212 	if (saddr->sa_family == AF_INET && (nmp->nm_flag & NFSMNT_RESVPORT)) {
213 		struct sockopt sopt;
214 		int ip;
215 		struct sockaddr_in ssin;
216 
217 		bzero(&sopt, sizeof sopt);
218 		ip = IP_PORTRANGE_LOW;
219 		sopt.sopt_level = IPPROTO_IP;
220 		sopt.sopt_name = IP_PORTRANGE;
221 		sopt.sopt_val = (void *)&ip;
222 		sopt.sopt_valsize = sizeof(ip);
223 		sopt.sopt_td = NULL;
224 		error = sosetopt(so, &sopt);
225 		if (error)
226 			goto bad;
227 		bzero(&ssin, sizeof ssin);
228 		sin = &ssin;
229 		sin->sin_len = sizeof (struct sockaddr_in);
230 		sin->sin_family = AF_INET;
231 		sin->sin_addr.s_addr = INADDR_ANY;
232 		sin->sin_port = htons(0);
233 		error = sobind(so, (struct sockaddr *)sin, td);
234 		if (error)
235 			goto bad;
236 		bzero(&sopt, sizeof sopt);
237 		ip = IP_PORTRANGE_DEFAULT;
238 		sopt.sopt_level = IPPROTO_IP;
239 		sopt.sopt_name = IP_PORTRANGE;
240 		sopt.sopt_val = (void *)&ip;
241 		sopt.sopt_valsize = sizeof(ip);
242 		sopt.sopt_td = NULL;
243 		error = sosetopt(so, &sopt);
244 		if (error)
245 			goto bad;
246 	}
247 
248 	/*
249 	 * Protocols that do not require connections may be optionally left
250 	 * unconnected for servers that reply from a port other than NFS_PORT.
251 	 */
252 	if (nmp->nm_flag & NFSMNT_NOCONN) {
253 		if (nmp->nm_soflags & PR_CONNREQUIRED) {
254 			error = ENOTCONN;
255 			goto bad;
256 		}
257 	} else {
258 		error = soconnect(so, nmp->nm_nam, td);
259 		if (error)
260 			goto bad;
261 
262 		/*
263 		 * Wait for the connection to complete. Cribbed from the
264 		 * connect system call but with the wait timing out so
265 		 * that interruptible mounts don't hang here for a long time.
266 		 */
267 		crit_enter();
268 		while ((so->so_state & SS_ISCONNECTING) && so->so_error == 0) {
269 			(void) tsleep((caddr_t)&so->so_timeo, 0,
270 				"nfscon", 2 * hz);
271 			if ((so->so_state & SS_ISCONNECTING) &&
272 			    so->so_error == 0 && rep &&
273 			    (error = nfs_sigintr(nmp, rep, rep->r_td)) != 0){
274 				soclrstate(so, SS_ISCONNECTING);
275 				crit_exit();
276 				goto bad;
277 			}
278 		}
279 		if (so->so_error) {
280 			error = so->so_error;
281 			so->so_error = 0;
282 			crit_exit();
283 			goto bad;
284 		}
285 		crit_exit();
286 	}
287 	so->so_rcv.ssb_timeo = (5 * hz);
288 	so->so_snd.ssb_timeo = (5 * hz);
289 
290 	/*
291 	 * Get buffer reservation size from sysctl, but impose reasonable
292 	 * limits.
293 	 */
294 	if (nmp->nm_sotype == SOCK_STREAM) {
295 		if (so->so_proto->pr_flags & PR_CONNREQUIRED) {
296 			struct sockopt sopt;
297 			int val;
298 
299 			bzero(&sopt, sizeof sopt);
300 			sopt.sopt_level = SOL_SOCKET;
301 			sopt.sopt_name = SO_KEEPALIVE;
302 			sopt.sopt_val = &val;
303 			sopt.sopt_valsize = sizeof val;
304 			val = 1;
305 			sosetopt(so, &sopt);
306 		}
307 		if (so->so_proto->pr_protocol == IPPROTO_TCP) {
308 			struct sockopt sopt;
309 			int val;
310 
311 			bzero(&sopt, sizeof sopt);
312 			sopt.sopt_level = IPPROTO_TCP;
313 			sopt.sopt_name = TCP_NODELAY;
314 			sopt.sopt_val = &val;
315 			sopt.sopt_valsize = sizeof val;
316 			val = 1;
317 			sosetopt(so, &sopt);
318 
319 			bzero(&sopt, sizeof sopt);
320 			sopt.sopt_level = IPPROTO_TCP;
321 			sopt.sopt_name = TCP_FASTKEEP;
322 			sopt.sopt_val = &val;
323 			sopt.sopt_valsize = sizeof val;
324 			val = 1;
325 			sosetopt(so, &sopt);
326 		}
327 	}
328 	error = soreserve(so, nfs_soreserve, nfs_soreserve, NULL);
329 	if (error)
330 		goto bad;
331 	atomic_set_int(&so->so_rcv.ssb_flags, SSB_NOINTR);
332 	atomic_set_int(&so->so_snd.ssb_flags, SSB_NOINTR);
333 
334 	/* Initialize other non-zero congestion variables */
335 	nmp->nm_srtt[0] = nmp->nm_srtt[1] = nmp->nm_srtt[2] =
336 		nmp->nm_srtt[3] = (NFS_TIMEO << NFS_RTT_SCALE_BITS);
337 	nmp->nm_sdrtt[0] = nmp->nm_sdrtt[1] = nmp->nm_sdrtt[2] =
338 		nmp->nm_sdrtt[3] = 0;
339 	nmp->nm_maxasync_scaled = NFS_MINASYNC_SCALED;
340 	nmp->nm_timeouts = 0;
341 
342 	/*
343 	 * Assign nm_so last.  The moment nm_so is assigned the nfs_timer()
344 	 * can mess with the socket.
345 	 */
346 	nmp->nm_so = so;
347 	return (0);
348 
349 bad:
350 	if (so) {
351 		soshutdown(so, SHUT_RDWR);
352 		soclose(so, FNONBLOCK);
353 	}
354 	return (error);
355 }
356 
357 /*
358  * Reconnect routine:
359  * Called when a connection is broken on a reliable protocol.
360  * - clean up the old socket
361  * - nfs_connect() again
362  * - set R_NEEDSXMIT for all outstanding requests on mount point
363  * If this fails the mount point is DEAD!
364  * nb: Must be called with the nfs_sndlock() set on the mount point.
365  */
366 static int
367 nfs_reconnect(struct nfsmount *nmp, struct nfsreq *rep)
368 {
369 	struct nfsreq *req;
370 	int error;
371 
372 	nfs_disconnect(nmp);
373 	if (nmp->nm_rxstate >= NFSSVC_STOPPING)
374 		return (EINTR);
375 	while ((error = nfs_connect(nmp, rep)) != 0) {
376 		if (error == EINTR || error == ERESTART)
377 			return (EINTR);
378 		if (error == EINVAL)
379 			return (error);
380 		if (nmp->nm_rxstate >= NFSSVC_STOPPING)
381 			return (EINTR);
382 		(void) tsleep((caddr_t)&lbolt, 0, "nfscon", 0);
383 	}
384 
385 	/*
386 	 * Loop through outstanding request list and fix up all requests
387 	 * on old socket.
388 	 */
389 	crit_enter();
390 	TAILQ_FOREACH(req, &nmp->nm_reqq, r_chain) {
391 		KKASSERT(req->r_nmp == nmp);
392 		req->r_flags |= R_NEEDSXMIT;
393 	}
394 	crit_exit();
395 	return (0);
396 }
397 
398 /*
399  * NFS disconnect. Clean up and unlink.
400  */
401 void
402 nfs_disconnect(struct nfsmount *nmp)
403 {
404 	struct socket *so;
405 
406 	if (nmp->nm_so) {
407 		so = nmp->nm_so;
408 		nmp->nm_so = NULL;
409 		soshutdown(so, SHUT_RDWR);
410 		soclose(so, FNONBLOCK);
411 	}
412 }
413 
414 void
415 nfs_safedisconnect(struct nfsmount *nmp)
416 {
417 	nfs_rcvlock(nmp, NULL);
418 	nfs_disconnect(nmp);
419 	nfs_rcvunlock(nmp);
420 }
421 
422 /*
423  * This is the nfs send routine. For connection based socket types, it
424  * must be called with an nfs_sndlock() on the socket.
425  * "rep == NULL" indicates that it has been called from a server.
426  * For the client side:
427  * - return EINTR if the RPC is terminated, 0 otherwise
428  * - set R_NEEDSXMIT if the send fails for any reason
429  * - do any cleanup required by recoverable socket errors (?)
430  * For the server side:
431  * - return EINTR or ERESTART if interrupted by a signal
432  * - return EPIPE if a connection is lost for connection based sockets (TCP...)
433  * - do any cleanup required by recoverable socket errors (?)
434  */
435 int
436 nfs_send(struct socket *so, struct sockaddr *nam, struct mbuf *top,
437 	 struct nfsreq *rep)
438 {
439 	struct sockaddr *sendnam;
440 	int error, soflags, flags;
441 
442 	if (rep) {
443 		if (rep->r_flags & R_SOFTTERM) {
444 			m_freem(top);
445 			return (EINTR);
446 		}
447 		if ((so = rep->r_nmp->nm_so) == NULL) {
448 			rep->r_flags |= R_NEEDSXMIT;
449 			m_freem(top);
450 			return (0);
451 		}
452 		rep->r_flags &= ~R_NEEDSXMIT;
453 		soflags = rep->r_nmp->nm_soflags;
454 	} else {
455 		soflags = so->so_proto->pr_flags;
456 	}
457 	if ((soflags & PR_CONNREQUIRED) || (so->so_state & SS_ISCONNECTED))
458 		sendnam = NULL;
459 	else
460 		sendnam = nam;
461 	if (so->so_type == SOCK_SEQPACKET)
462 		flags = MSG_EOR;
463 	else
464 		flags = 0;
465 
466 	/*
467 	 * calls pru_sosend -> sosend -> so_pru_send -> netrpc
468 	 */
469 	error = so_pru_sosend(so, sendnam, NULL, top, NULL, flags,
470 			      curthread /*XXX*/);
471 
472 	/*
473 	 * ENOBUFS for dgram sockets is transient and non fatal.
474 	 * No need to log, and no need to break a soft mount.
475 	 */
476 	if (error == ENOBUFS && so->so_type == SOCK_DGRAM) {
477 		error = 0;
478 		/*
479 		 * do backoff retransmit on client
480 		 */
481 		if (rep) {
482 			if ((rep->r_nmp->nm_state & NFSSTA_SENDSPACE) == 0) {
483 				rep->r_nmp->nm_state |= NFSSTA_SENDSPACE;
484 				kprintf("Warning: NFS: Insufficient sendspace "
485 					"(%lu),\n"
486 					"\t You must increase vfs.nfs.soreserve"
487 					"or decrease vfs.nfs.maxasyncbio\n",
488 					so->so_snd.ssb_hiwat);
489 			}
490 			rep->r_flags |= R_NEEDSXMIT;
491 		}
492 	}
493 
494 	if (error) {
495 		if (rep) {
496 			log(LOG_INFO, "nfs send error %d for server %s\n",error,
497 			    rep->r_nmp->nm_mountp->mnt_stat.f_mntfromname);
498 			/*
499 			 * Deal with errors for the client side.
500 			 */
501 			if (rep->r_flags & R_SOFTTERM)
502 				error = EINTR;
503 			else
504 				rep->r_flags |= R_NEEDSXMIT;
505 		} else {
506 			log(LOG_INFO, "nfsd send error %d\n", error);
507 		}
508 
509 		/*
510 		 * Handle any recoverable (soft) socket errors here. (?)
511 		 */
512 		if (error != EINTR && error != ERESTART &&
513 			error != EWOULDBLOCK && error != EPIPE)
514 			error = 0;
515 	}
516 	return (error);
517 }
518 
519 /*
520  * Receive a Sun RPC Request/Reply. For SOCK_DGRAM, the work is all
521  * done by soreceive(), but for SOCK_STREAM we must deal with the Record
522  * Mark and consolidate the data into a new mbuf list.
523  * nb: Sometimes TCP passes the data up to soreceive() in long lists of
524  *     small mbufs.
525  * For SOCK_STREAM we must be very careful to read an entire record once
526  * we have read any of it, even if the system call has been interrupted.
527  */
528 static int
529 nfs_receive(struct nfsmount *nmp, struct nfsreq *rep,
530 	    struct sockaddr **aname, struct mbuf **mp)
531 {
532 	struct socket *so;
533 	struct sockbuf sio;
534 	struct uio auio;
535 	struct iovec aio;
536 	struct mbuf *m;
537 	struct mbuf *control;
538 	u_int32_t len;
539 	struct sockaddr **getnam;
540 	int error, sotype, rcvflg;
541 	struct thread *td = curthread;	/* XXX */
542 
543 	/*
544 	 * Set up arguments for soreceive()
545 	 */
546 	*mp = NULL;
547 	*aname = NULL;
548 	sotype = nmp->nm_sotype;
549 
550 	/*
551 	 * For reliable protocols, lock against other senders/receivers
552 	 * in case a reconnect is necessary.
553 	 * For SOCK_STREAM, first get the Record Mark to find out how much
554 	 * more there is to get.
555 	 * We must lock the socket against other receivers
556 	 * until we have an entire rpc request/reply.
557 	 */
558 	if (sotype != SOCK_DGRAM) {
559 		error = nfs_sndlock(nmp, rep);
560 		if (error)
561 			return (error);
562 tryagain:
563 		/*
564 		 * Check for fatal errors and resending request.
565 		 */
566 		/*
567 		 * Ugh: If a reconnect attempt just happened, nm_so
568 		 * would have changed. NULL indicates a failed
569 		 * attempt that has essentially shut down this
570 		 * mount point.
571 		 */
572 		if (rep && (rep->r_mrep || (rep->r_flags & R_SOFTTERM))) {
573 			nfs_sndunlock(nmp);
574 			return (EINTR);
575 		}
576 		so = nmp->nm_so;
577 		if (so == NULL) {
578 			error = nfs_reconnect(nmp, rep);
579 			if (error) {
580 				nfs_sndunlock(nmp);
581 				return (error);
582 			}
583 			goto tryagain;
584 		}
585 		while (rep && (rep->r_flags & R_NEEDSXMIT)) {
586 			m = m_copym(rep->r_mreq, 0, M_COPYALL, MB_WAIT);
587 			nfsstats.rpcretries++;
588 			error = nfs_send(so, rep->r_nmp->nm_nam, m, rep);
589 			if (error) {
590 				if (error == EINTR || error == ERESTART ||
591 				    (error = nfs_reconnect(nmp, rep)) != 0) {
592 					nfs_sndunlock(nmp);
593 					return (error);
594 				}
595 				goto tryagain;
596 			}
597 		}
598 		nfs_sndunlock(nmp);
599 		if (sotype == SOCK_STREAM) {
600 			/*
601 			 * Get the length marker from the stream
602 			 */
603 			aio.iov_base = (caddr_t)&len;
604 			aio.iov_len = sizeof(u_int32_t);
605 			auio.uio_iov = &aio;
606 			auio.uio_iovcnt = 1;
607 			auio.uio_segflg = UIO_SYSSPACE;
608 			auio.uio_rw = UIO_READ;
609 			auio.uio_offset = 0;
610 			auio.uio_resid = sizeof(u_int32_t);
611 			auio.uio_td = td;
612 			do {
613 			   rcvflg = MSG_WAITALL;
614 			   error = so_pru_soreceive(so, NULL, &auio, NULL,
615 						    NULL, &rcvflg);
616 			   if (error == EWOULDBLOCK && rep) {
617 				if (rep->r_flags & R_SOFTTERM)
618 					return (EINTR);
619 			   }
620 			} while (error == EWOULDBLOCK);
621 
622 			if (error == 0 && auio.uio_resid > 0) {
623 			    /*
624 			     * Only log short packets if not EOF
625 			     */
626 			    if (auio.uio_resid != sizeof(u_int32_t)) {
627 				log(LOG_INFO,
628 				    "short receive (%d/%d) from nfs server %s\n",
629 				    (int)(sizeof(u_int32_t) - auio.uio_resid),
630 				    (int)sizeof(u_int32_t),
631 				    nmp->nm_mountp->mnt_stat.f_mntfromname);
632 			    }
633 			    error = EPIPE;
634 			}
635 			if (error)
636 				goto errout;
637 			len = ntohl(len) & ~0x80000000;
638 			/*
639 			 * This is SERIOUS! We are out of sync with the sender
640 			 * and forcing a disconnect/reconnect is all I can do.
641 			 */
642 			if (len > NFS_MAXPACKET) {
643 			    log(LOG_ERR, "%s (%d) from nfs server %s\n",
644 				"impossible packet length",
645 				len,
646 				nmp->nm_mountp->mnt_stat.f_mntfromname);
647 			    error = EFBIG;
648 			    goto errout;
649 			}
650 
651 			/*
652 			 * Get the rest of the packet as an mbuf chain
653 			 */
654 			sbinit(&sio, len);
655 			do {
656 			    rcvflg = MSG_WAITALL;
657 			    error = so_pru_soreceive(so, NULL, NULL, &sio,
658 						     NULL, &rcvflg);
659 			} while (error == EWOULDBLOCK || error == EINTR ||
660 				 error == ERESTART);
661 			if (error == 0 && sio.sb_cc != len) {
662 			    if (sio.sb_cc != 0) {
663 				log(LOG_INFO,
664 				    "short receive (%zu/%d) from nfs server %s\n",
665 				    (size_t)len - auio.uio_resid, len,
666 				    nmp->nm_mountp->mnt_stat.f_mntfromname);
667 			    }
668 			    error = EPIPE;
669 			}
670 			*mp = sio.sb_mb;
671 		} else {
672 			/*
673 			 * Non-stream, so get the whole packet by not
674 			 * specifying MSG_WAITALL and by specifying a large
675 			 * length.
676 			 *
677 			 * We have no use for control msg., but must grab them
678 			 * and then throw them away so we know what is going
679 			 * on.
680 			 */
681 			sbinit(&sio, 100000000);
682 			do {
683 			    rcvflg = 0;
684 			    error =  so_pru_soreceive(so, NULL, NULL, &sio,
685 						      &control, &rcvflg);
686 			    if (control)
687 				m_freem(control);
688 			    if (error == EWOULDBLOCK && rep) {
689 				if (rep->r_flags & R_SOFTTERM) {
690 					m_freem(sio.sb_mb);
691 					return (EINTR);
692 				}
693 			    }
694 			} while (error == EWOULDBLOCK ||
695 				 (error == 0 && sio.sb_mb == NULL && control));
696 			if ((rcvflg & MSG_EOR) == 0)
697 				kprintf("Egad!!\n");
698 			if (error == 0 && sio.sb_mb == NULL)
699 				error = EPIPE;
700 			len = sio.sb_cc;
701 			*mp = sio.sb_mb;
702 		}
703 errout:
704 		if (error && error != EINTR && error != ERESTART) {
705 			m_freem(*mp);
706 			*mp = NULL;
707 			if (error != EPIPE) {
708 				log(LOG_INFO,
709 				    "receive error %d from nfs server %s\n",
710 				    error,
711 				 nmp->nm_mountp->mnt_stat.f_mntfromname);
712 			}
713 			error = nfs_sndlock(nmp, rep);
714 			if (!error) {
715 				error = nfs_reconnect(nmp, rep);
716 				if (!error)
717 					goto tryagain;
718 				else
719 					nfs_sndunlock(nmp);
720 			}
721 		}
722 	} else {
723 		if ((so = nmp->nm_so) == NULL)
724 			return (EACCES);
725 		if (so->so_state & SS_ISCONNECTED)
726 			getnam = NULL;
727 		else
728 			getnam = aname;
729 		sbinit(&sio, 100000000);
730 		do {
731 			rcvflg = 0;
732 			error =  so_pru_soreceive(so, getnam, NULL, &sio,
733 						  NULL, &rcvflg);
734 			if (error == EWOULDBLOCK && rep &&
735 			    (rep->r_flags & R_SOFTTERM)) {
736 				m_freem(sio.sb_mb);
737 				return (EINTR);
738 			}
739 		} while (error == EWOULDBLOCK);
740 
741 		len = sio.sb_cc;
742 		*mp = sio.sb_mb;
743 
744 		/*
745 		 * A shutdown may result in no error and no mbuf.
746 		 * Convert to EPIPE.
747 		 */
748 		if (*mp == NULL && error == 0)
749 			error = EPIPE;
750 	}
751 	if (error) {
752 		m_freem(*mp);
753 		*mp = NULL;
754 	}
755 
756 	/*
757 	 * Search for any mbufs that are not a multiple of 4 bytes long
758 	 * or with m_data not longword aligned.
759 	 * These could cause pointer alignment problems, so copy them to
760 	 * well aligned mbufs.
761 	 */
762 	nfs_realign(mp, 5 * NFSX_UNSIGNED);
763 	return (error);
764 }
765 
766 /*
767  * Implement receipt of reply on a socket.
768  *
769  * We must search through the list of received datagrams matching them
770  * with outstanding requests using the xid, until ours is found.
771  *
772  * If myrep is NULL we process packets on the socket until
773  * interrupted or until nm_reqrxq is non-empty.
774  */
775 /* ARGSUSED */
776 int
777 nfs_reply(struct nfsmount *nmp, struct nfsreq *myrep)
778 {
779 	struct nfsreq *rep;
780 	struct sockaddr *nam;
781 	u_int32_t rxid;
782 	u_int32_t *tl;
783 	int error;
784 	struct nfsm_info info;
785 
786 	/*
787 	 * Loop around until we get our own reply
788 	 */
789 	for (;;) {
790 		/*
791 		 * Lock against other receivers so that I don't get stuck in
792 		 * sbwait() after someone else has received my reply for me.
793 		 * Also necessary for connection based protocols to avoid
794 		 * race conditions during a reconnect.
795 		 *
796 		 * If nfs_rcvlock() returns EALREADY, that means that
797 		 * the reply has already been recieved by another
798 		 * process and we can return immediately.  In this
799 		 * case, the lock is not taken to avoid races with
800 		 * other processes.
801 		 */
802 		info.mrep = NULL;
803 
804 		error = nfs_rcvlock(nmp, myrep);
805 		if (error == EALREADY)
806 			return (0);
807 		if (error)
808 			return (error);
809 
810 		/*
811 		 * If myrep is NULL we are the receiver helper thread.
812 		 * Stop waiting for incoming replies if there are
813 		 * messages sitting on reqrxq that we need to process,
814 		 * or if a shutdown request is pending.
815 		 */
816 		if (myrep == NULL && (TAILQ_FIRST(&nmp->nm_reqrxq) ||
817 		    nmp->nm_rxstate > NFSSVC_PENDING)) {
818 			nfs_rcvunlock(nmp);
819 			return(EWOULDBLOCK);
820 		}
821 
822 		/*
823 		 * Get the next Rpc reply off the socket
824 		 *
825 		 * We cannot release the receive lock until we've
826 		 * filled in rep->r_mrep, otherwise a waiting
827 		 * thread may deadlock in soreceive with no incoming
828 		 * packets expected.
829 		 */
830 		error = nfs_receive(nmp, myrep, &nam, &info.mrep);
831 		if (error) {
832 			/*
833 			 * Ignore routing errors on connectionless protocols??
834 			 */
835 			nfs_rcvunlock(nmp);
836 			if (NFSIGNORE_SOERROR(nmp->nm_soflags, error)) {
837 				if (nmp->nm_so == NULL)
838 					return (error);
839 				nmp->nm_so->so_error = 0;
840 				continue;
841 			}
842 			return (error);
843 		}
844 		if (nam)
845 			kfree(nam, M_SONAME);
846 
847 		/*
848 		 * Get the xid and check that it is an rpc reply
849 		 */
850 		info.md = info.mrep;
851 		info.dpos = mtod(info.md, caddr_t);
852 		NULLOUT(tl = nfsm_dissect(&info, 2*NFSX_UNSIGNED));
853 		rxid = *tl++;
854 		if (*tl != rpc_reply) {
855 			nfsstats.rpcinvalid++;
856 			m_freem(info.mrep);
857 			info.mrep = NULL;
858 nfsmout:
859 			nfs_rcvunlock(nmp);
860 			continue;
861 		}
862 
863 		/*
864 		 * Loop through the request list to match up the reply
865 		 * Iff no match, just drop the datagram.  On match, set
866 		 * r_mrep atomically to prevent the timer from messing
867 		 * around with the request after we have exited the critical
868 		 * section.
869 		 */
870 		crit_enter();
871 		TAILQ_FOREACH(rep, &nmp->nm_reqq, r_chain) {
872 			if (rep->r_mrep == NULL && rxid == rep->r_xid)
873 				break;
874 		}
875 
876 		/*
877 		 * Fill in the rest of the reply if we found a match.
878 		 *
879 		 * Deal with duplicate responses if there was no match.
880 		 */
881 		if (rep) {
882 			rep->r_md = info.md;
883 			rep->r_dpos = info.dpos;
884 			if (nfsrtton) {
885 				struct rttl *rt;
886 
887 				rt = &nfsrtt.rttl[nfsrtt.pos];
888 				rt->proc = rep->r_procnum;
889 				rt->rto = 0;
890 				rt->sent = 0;
891 				rt->cwnd = nmp->nm_maxasync_scaled;
892 				rt->srtt = nmp->nm_srtt[proct[rep->r_procnum] - 1];
893 				rt->sdrtt = nmp->nm_sdrtt[proct[rep->r_procnum] - 1];
894 				rt->fsid = nmp->nm_mountp->mnt_stat.f_fsid;
895 				getmicrotime(&rt->tstamp);
896 				if (rep->r_flags & R_TIMING)
897 					rt->rtt = rep->r_rtt;
898 				else
899 					rt->rtt = 1000000;
900 				nfsrtt.pos = (nfsrtt.pos + 1) % NFSRTTLOGSIZ;
901 			}
902 
903 			/*
904 			 * New congestion control is based only on async
905 			 * requests.
906 			 */
907 			if (nmp->nm_maxasync_scaled < NFS_MAXASYNC_SCALED)
908 				++nmp->nm_maxasync_scaled;
909 			if (rep->r_flags & R_SENT) {
910 				rep->r_flags &= ~R_SENT;
911 			}
912 			/*
913 			 * Update rtt using a gain of 0.125 on the mean
914 			 * and a gain of 0.25 on the deviation.
915 			 *
916 			 * NOTE SRTT/SDRTT are only good if R_TIMING is set.
917 			 */
918 			if ((rep->r_flags & R_TIMING) && rep->r_rexmit == 0) {
919 				/*
920 				 * Since the timer resolution of
921 				 * NFS_HZ is so course, it can often
922 				 * result in r_rtt == 0. Since
923 				 * r_rtt == N means that the actual
924 				 * rtt is between N+dt and N+2-dt ticks,
925 				 * add 1.
926 				 */
927 				int n;
928 				int d;
929 
930 #define NFSRSB	NFS_RTT_SCALE_BITS
931 				n = ((NFS_SRTT(rep) * 7) +
932 				     (rep->r_rtt << NFSRSB)) >> 3;
933 				d = n - NFS_SRTT(rep);
934 				NFS_SRTT(rep) = n;
935 
936 				/*
937 				 * Don't let the jitter calculation decay
938 				 * too quickly, but we want a fast rampup.
939 				 */
940 				if (d < 0)
941 					d = -d;
942 				d <<= NFSRSB;
943 				if (d < NFS_SDRTT(rep))
944 					n = ((NFS_SDRTT(rep) * 15) + d) >> 4;
945 				else
946 					n = ((NFS_SDRTT(rep) * 3) + d) >> 2;
947 				NFS_SDRTT(rep) = n;
948 #undef NFSRSB
949 			}
950 			nmp->nm_timeouts = 0;
951 			rep->r_mrep = info.mrep;
952 			nfs_hardterm(rep, 0);
953 		} else {
954 			/*
955 			 * Extract vers, prog, nfsver, procnum.  A duplicate
956 			 * response means we didn't wait long enough so
957 			 * we increase the SRTT to avoid future spurious
958 			 * timeouts.
959 			 */
960 			u_int procnum = nmp->nm_lastreprocnum;
961 			int n;
962 
963 			if (procnum < NFS_NPROCS && proct[procnum]) {
964 				if (nfs_showrexmit)
965 					kprintf("D");
966 				n = nmp->nm_srtt[proct[procnum]];
967 				n += NFS_ASYSCALE * NFS_HZ;
968 				if (n < NFS_ASYSCALE * NFS_HZ * 10)
969 					n = NFS_ASYSCALE * NFS_HZ * 10;
970 				nmp->nm_srtt[proct[procnum]] = n;
971 			}
972 		}
973 		nfs_rcvunlock(nmp);
974 		crit_exit();
975 
976 		/*
977 		 * If not matched to a request, drop it.
978 		 * If it's mine, get out.
979 		 */
980 		if (rep == NULL) {
981 			nfsstats.rpcunexpected++;
982 			m_freem(info.mrep);
983 			info.mrep = NULL;
984 		} else if (rep == myrep) {
985 			if (rep->r_mrep == NULL)
986 				panic("nfsreply nil");
987 			return (0);
988 		}
989 	}
990 }
991 
992 /*
993  * Run the request state machine until the target state is reached
994  * or a fatal error occurs.  The target state is not run.  Specifying
995  * a target of NFSM_STATE_DONE runs the state machine until the rpc
996  * is complete.
997  *
998  * EINPROGRESS is returned for all states other then the DONE state,
999  * indicating that the rpc is still in progress.
1000  */
1001 int
1002 nfs_request(struct nfsm_info *info, nfsm_state_t bstate, nfsm_state_t estate)
1003 {
1004 	struct nfsreq *req;
1005 
1006 	while (info->state >= bstate && info->state < estate) {
1007 		switch(info->state) {
1008 		case NFSM_STATE_SETUP:
1009 			/*
1010 			 * Setup the nfsreq.  Any error which occurs during
1011 			 * this state is fatal.
1012 			 */
1013 			info->error = nfs_request_setup(info);
1014 			if (info->error) {
1015 				info->state = NFSM_STATE_DONE;
1016 				return (info->error);
1017 			} else {
1018 				req = info->req;
1019 				req->r_mrp = &info->mrep;
1020 				req->r_mdp = &info->md;
1021 				req->r_dposp = &info->dpos;
1022 				info->state = NFSM_STATE_AUTH;
1023 			}
1024 			break;
1025 		case NFSM_STATE_AUTH:
1026 			/*
1027 			 * Authenticate the nfsreq.  Any error which occurs
1028 			 * during this state is fatal.
1029 			 */
1030 			info->error = nfs_request_auth(info->req);
1031 			if (info->error) {
1032 				info->state = NFSM_STATE_DONE;
1033 				return (info->error);
1034 			} else {
1035 				info->state = NFSM_STATE_TRY;
1036 			}
1037 			break;
1038 		case NFSM_STATE_TRY:
1039 			/*
1040 			 * Transmit or retransmit attempt.  An error in this
1041 			 * state is ignored and we always move on to the
1042 			 * next state.
1043 			 *
1044 			 * This can trivially race the receiver if the
1045 			 * request is asynchronous.  nfs_request_try()
1046 			 * will thus set the state for us and we
1047 			 * must also return immediately if we are
1048 			 * running an async state machine, because
1049 			 * info can become invalid due to races after
1050 			 * try() returns.
1051 			 */
1052 			if (info->req->r_flags & R_ASYNC) {
1053 				nfs_request_try(info->req);
1054 				if (estate == NFSM_STATE_WAITREPLY)
1055 					return (EINPROGRESS);
1056 			} else {
1057 				nfs_request_try(info->req);
1058 				info->state = NFSM_STATE_WAITREPLY;
1059 			}
1060 			break;
1061 		case NFSM_STATE_WAITREPLY:
1062 			/*
1063 			 * Wait for a reply or timeout and move on to the
1064 			 * next state.  The error returned by this state
1065 			 * is passed to the processing code in the next
1066 			 * state.
1067 			 */
1068 			info->error = nfs_request_waitreply(info->req);
1069 			info->state = NFSM_STATE_PROCESSREPLY;
1070 			break;
1071 		case NFSM_STATE_PROCESSREPLY:
1072 			/*
1073 			 * Process the reply or timeout.  Errors which occur
1074 			 * in this state may cause the state machine to
1075 			 * go back to an earlier state, and are fatal
1076 			 * otherwise.
1077 			 */
1078 			info->error = nfs_request_processreply(info,
1079 							       info->error);
1080 			switch(info->error) {
1081 			case ENEEDAUTH:
1082 				info->state = NFSM_STATE_AUTH;
1083 				break;
1084 			case EAGAIN:
1085 				info->state = NFSM_STATE_TRY;
1086 				break;
1087 			default:
1088 				/*
1089 				 * Operation complete, with or without an
1090 				 * error.  We are done.
1091 				 */
1092 				info->req = NULL;
1093 				info->state = NFSM_STATE_DONE;
1094 				return (info->error);
1095 			}
1096 			break;
1097 		case NFSM_STATE_DONE:
1098 			/*
1099 			 * Shouldn't be reached
1100 			 */
1101 			return (info->error);
1102 			/* NOT REACHED */
1103 		}
1104 	}
1105 
1106 	/*
1107 	 * If we are done return the error code (if any).
1108 	 * Otherwise return EINPROGRESS.
1109 	 */
1110 	if (info->state == NFSM_STATE_DONE)
1111 		return (info->error);
1112 	return (EINPROGRESS);
1113 }
1114 
1115 /*
1116  * nfs_request - goes something like this
1117  *	- fill in request struct
1118  *	- links it into list
1119  *	- calls nfs_send() for first transmit
1120  *	- calls nfs_receive() to get reply
1121  *	- break down rpc header and return with nfs reply pointed to
1122  *	  by mrep or error
1123  * nb: always frees up mreq mbuf list
1124  */
1125 static int
1126 nfs_request_setup(nfsm_info_t info)
1127 {
1128 	struct nfsreq *req;
1129 	struct nfsmount *nmp;
1130 	struct mbuf *m;
1131 	int i;
1132 
1133 	/*
1134 	 * Reject requests while attempting a forced unmount.
1135 	 */
1136 	if (info->vp->v_mount->mnt_kern_flag & MNTK_UNMOUNTF) {
1137 		m_freem(info->mreq);
1138 		info->mreq = NULL;
1139 		return (EIO);
1140 	}
1141 	nmp = VFSTONFS(info->vp->v_mount);
1142 	req = kmalloc(sizeof(struct nfsreq), M_NFSREQ, M_WAITOK);
1143 	req->r_nmp = nmp;
1144 	req->r_vp = info->vp;
1145 	req->r_td = info->td;
1146 	req->r_procnum = info->procnum;
1147 	req->r_mreq = NULL;
1148 	req->r_cred = info->cred;
1149 
1150 	i = 0;
1151 	m = info->mreq;
1152 	while (m) {
1153 		i += m->m_len;
1154 		m = m->m_next;
1155 	}
1156 	req->r_mrest = info->mreq;
1157 	req->r_mrest_len = i;
1158 
1159 	/*
1160 	 * The presence of a non-NULL r_info in req indicates
1161 	 * async completion via our helper threads.  See the receiver
1162 	 * code.
1163 	 */
1164 	if (info->bio) {
1165 		req->r_info = info;
1166 		req->r_flags = R_ASYNC;
1167 	} else {
1168 		req->r_info = NULL;
1169 		req->r_flags = 0;
1170 	}
1171 	info->req = req;
1172 	return(0);
1173 }
1174 
1175 static int
1176 nfs_request_auth(struct nfsreq *rep)
1177 {
1178 	struct nfsmount *nmp = rep->r_nmp;
1179 	struct mbuf *m;
1180 	char nickv[RPCX_NICKVERF];
1181 	int error = 0, auth_len, auth_type;
1182 	int verf_len;
1183 	u_int32_t xid;
1184 	char *auth_str, *verf_str;
1185 	struct ucred *cred;
1186 
1187 	cred = rep->r_cred;
1188 	rep->r_failed_auth = 0;
1189 
1190 	/*
1191 	 * Get the RPC header with authorization.
1192 	 */
1193 	verf_str = auth_str = NULL;
1194 	if (nmp->nm_flag & NFSMNT_KERB) {
1195 		verf_str = nickv;
1196 		verf_len = sizeof (nickv);
1197 		auth_type = RPCAUTH_KERB4;
1198 		bzero((caddr_t)rep->r_key, sizeof(rep->r_key));
1199 		if (rep->r_failed_auth ||
1200 		    nfs_getnickauth(nmp, cred, &auth_str, &auth_len,
1201 				    verf_str, verf_len)) {
1202 			error = nfs_getauth(nmp, rep, cred, &auth_str,
1203 				&auth_len, verf_str, &verf_len, rep->r_key);
1204 			if (error) {
1205 				m_freem(rep->r_mrest);
1206 				rep->r_mrest = NULL;
1207 				kfree((caddr_t)rep, M_NFSREQ);
1208 				return (error);
1209 			}
1210 		}
1211 	} else {
1212 		auth_type = RPCAUTH_UNIX;
1213 		if (cred->cr_ngroups < 1)
1214 			panic("nfsreq nogrps");
1215 		auth_len = ((((cred->cr_ngroups - 1) > nmp->nm_numgrps) ?
1216 			nmp->nm_numgrps : (cred->cr_ngroups - 1)) << 2) +
1217 			5 * NFSX_UNSIGNED;
1218 	}
1219 	if (rep->r_mrest)
1220 		nfs_checkpkt(rep->r_mrest, rep->r_mrest_len);
1221 	m = nfsm_rpchead(cred, nmp->nm_flag, rep->r_procnum, auth_type,
1222 			auth_len, auth_str, verf_len, verf_str,
1223 			rep->r_mrest, rep->r_mrest_len, &rep->r_mheadend, &xid);
1224 	rep->r_mrest = NULL;
1225 	if (auth_str)
1226 		kfree(auth_str, M_TEMP);
1227 
1228 	/*
1229 	 * For stream protocols, insert a Sun RPC Record Mark.
1230 	 */
1231 	if (nmp->nm_sotype == SOCK_STREAM) {
1232 		M_PREPEND(m, NFSX_UNSIGNED, MB_WAIT);
1233 		if (m == NULL) {
1234 			kfree(rep, M_NFSREQ);
1235 			return (ENOBUFS);
1236 		}
1237 		*mtod(m, u_int32_t *) = htonl(0x80000000 |
1238 			 (m->m_pkthdr.len - NFSX_UNSIGNED));
1239 	}
1240 
1241 	nfs_checkpkt(m, m->m_pkthdr.len);
1242 
1243 	rep->r_mreq = m;
1244 	rep->r_xid = xid;
1245 	return (0);
1246 }
1247 
1248 static int
1249 nfs_request_try(struct nfsreq *rep)
1250 {
1251 	struct nfsmount *nmp = rep->r_nmp;
1252 	struct mbuf *m2;
1253 	int error;
1254 
1255 	/*
1256 	 * Request is not on any queue, only the owner has access to it
1257 	 * so it should not be locked by anyone atm.
1258 	 *
1259 	 * Interlock to prevent races.  While locked the only remote
1260 	 * action possible is for r_mrep to be set (once we enqueue it).
1261 	 */
1262 	if (rep->r_flags == 0xdeadc0de) {
1263 		print_backtrace(-1);
1264 		panic("flags nbad");
1265 	}
1266 	KKASSERT((rep->r_flags & (R_LOCKED | R_ONREQQ)) == 0);
1267 	if (nmp->nm_flag & NFSMNT_SOFT)
1268 		rep->r_retry = nmp->nm_retry;
1269 	else
1270 		rep->r_retry = NFS_MAXREXMIT + 1;	/* past clip limit */
1271 	rep->r_rtt = rep->r_rexmit = 0;
1272 	if (proct[rep->r_procnum] > 0)
1273 		rep->r_flags |= R_TIMING | R_LOCKED;
1274 	else
1275 		rep->r_flags |= R_LOCKED;
1276 	rep->r_mrep = NULL;
1277 
1278 	nfsstats.rpcrequests++;
1279 
1280 	if (nmp->nm_flag & NFSMNT_FORCE) {
1281 		rep->r_flags |= R_SOFTTERM;
1282 		rep->r_flags &= ~R_LOCKED;
1283 		return (0);
1284 	}
1285 	rep->r_flags |= R_NEEDSXMIT;	/* in case send lock races us */
1286 
1287 	/*
1288 	 * Do the client side RPC.
1289 	 *
1290 	 * Chain request into list of outstanding requests. Be sure
1291 	 * to put it LAST so timer finds oldest requests first.  Note
1292 	 * that our control of R_LOCKED prevents the request from
1293 	 * getting ripped out from under us or transmitted by the
1294 	 * timer code.
1295 	 *
1296 	 * For requests with info structures we must atomically set the
1297 	 * info's state because the structure could become invalid upon
1298 	 * return due to races (i.e., if async)
1299 	 */
1300 	crit_enter();
1301 	mtx_link_init(&rep->r_link);
1302 	KKASSERT((rep->r_flags & R_ONREQQ) == 0);
1303 	TAILQ_INSERT_TAIL(&nmp->nm_reqq, rep, r_chain);
1304 	rep->r_flags |= R_ONREQQ;
1305 	++nmp->nm_reqqlen;
1306 	if (rep->r_flags & R_ASYNC)
1307 		rep->r_info->state = NFSM_STATE_WAITREPLY;
1308 	crit_exit();
1309 
1310 	error = 0;
1311 
1312 	/*
1313 	 * Send if we can.  Congestion control is not handled here any more
1314 	 * becausing trying to defer the initial send based on the nfs_timer
1315 	 * requires having a very fast nfs_timer, which is silly.
1316 	 */
1317 	if (nmp->nm_so) {
1318 		if (nmp->nm_soflags & PR_CONNREQUIRED)
1319 			error = nfs_sndlock(nmp, rep);
1320 		if (error == 0 && (rep->r_flags & R_NEEDSXMIT)) {
1321 			m2 = m_copym(rep->r_mreq, 0, M_COPYALL, MB_WAIT);
1322 			error = nfs_send(nmp->nm_so, nmp->nm_nam, m2, rep);
1323 			rep->r_flags &= ~R_NEEDSXMIT;
1324 			if ((rep->r_flags & R_SENT) == 0) {
1325 				rep->r_flags |= R_SENT;
1326 			}
1327 			if (nmp->nm_soflags & PR_CONNREQUIRED)
1328 				nfs_sndunlock(nmp);
1329 		}
1330 	} else {
1331 		rep->r_rtt = -1;
1332 	}
1333 	if (error == EPIPE)
1334 		error = 0;
1335 
1336 	/*
1337 	 * Release the lock.  The only remote action that may have occurred
1338 	 * would have been the setting of rep->r_mrep.  If this occured
1339 	 * and the request was async we have to move it to the reader
1340 	 * thread's queue for action.
1341 	 *
1342 	 * For async requests also make sure the reader is woken up so
1343 	 * it gets on the socket to read responses.
1344 	 */
1345 	crit_enter();
1346 	if (rep->r_flags & R_ASYNC) {
1347 		if (rep->r_mrep)
1348 			nfs_hardterm(rep, 1);
1349 		rep->r_flags &= ~R_LOCKED;
1350 		nfssvc_iod_reader_wakeup(nmp);
1351 	} else {
1352 		rep->r_flags &= ~R_LOCKED;
1353 	}
1354 	if (rep->r_flags & R_WANTED) {
1355 		rep->r_flags &= ~R_WANTED;
1356 		wakeup(rep);
1357 	}
1358 	crit_exit();
1359 	return (error);
1360 }
1361 
1362 /*
1363  * This code is only called for synchronous requests.  Completed synchronous
1364  * requests are left on reqq and we remove them before moving on to the
1365  * processing state.
1366  */
1367 static int
1368 nfs_request_waitreply(struct nfsreq *rep)
1369 {
1370 	struct nfsmount *nmp = rep->r_nmp;
1371 	int error;
1372 
1373 	KKASSERT((rep->r_flags & R_ASYNC) == 0);
1374 
1375 	/*
1376 	 * Wait until the request is finished.
1377 	 */
1378 	error = nfs_reply(nmp, rep);
1379 
1380 	/*
1381 	 * RPC done, unlink the request, but don't rip it out from under
1382 	 * the callout timer.
1383 	 *
1384 	 * Once unlinked no other receiver or the timer will have
1385 	 * visibility, so we do not have to set R_LOCKED.
1386 	 */
1387 	crit_enter();
1388 	while (rep->r_flags & R_LOCKED) {
1389 		rep->r_flags |= R_WANTED;
1390 		tsleep(rep, 0, "nfstrac", 0);
1391 	}
1392 	KKASSERT(rep->r_flags & R_ONREQQ);
1393 	TAILQ_REMOVE(&nmp->nm_reqq, rep, r_chain);
1394 	rep->r_flags &= ~R_ONREQQ;
1395 	--nmp->nm_reqqlen;
1396 	if (TAILQ_FIRST(&nmp->nm_bioq) &&
1397 	    nmp->nm_reqqlen <= nfs_maxasyncbio * 2 / 3) {
1398 		nfssvc_iod_writer_wakeup(nmp);
1399 	}
1400 	crit_exit();
1401 
1402 	/*
1403 	 * Decrement the outstanding request count.
1404 	 */
1405 	if (rep->r_flags & R_SENT) {
1406 		rep->r_flags &= ~R_SENT;
1407 	}
1408 	return (error);
1409 }
1410 
1411 /*
1412  * Process reply with error returned from nfs_requet_waitreply().
1413  *
1414  * Returns EAGAIN if it wants us to loop up to nfs_request_try() again.
1415  * Returns ENEEDAUTH if it wants us to loop up to nfs_request_auth() again.
1416  */
1417 static int
1418 nfs_request_processreply(nfsm_info_t info, int error)
1419 {
1420 	struct nfsreq *req = info->req;
1421 	struct nfsmount *nmp = req->r_nmp;
1422 	u_int32_t *tl;
1423 	int verf_type;
1424 	int i;
1425 
1426 	/*
1427 	 * If there was a successful reply and a tprintf msg.
1428 	 * tprintf a response.
1429 	 */
1430 	if (error == 0 && (req->r_flags & R_TPRINTFMSG)) {
1431 		nfs_msg(req->r_td, nmp->nm_mountp->mnt_stat.f_mntfromname,
1432 		    "is alive again");
1433 	}
1434 	info->mrep = req->r_mrep;
1435 	info->md = req->r_md;
1436 	info->dpos = req->r_dpos;
1437 	if (error) {
1438 		m_freem(req->r_mreq);
1439 		req->r_mreq = NULL;
1440 		kfree(req, M_NFSREQ);
1441 		info->req = NULL;
1442 		return (error);
1443 	}
1444 
1445 	/*
1446 	 * break down the rpc header and check if ok
1447 	 */
1448 	NULLOUT(tl = nfsm_dissect(info, 3 * NFSX_UNSIGNED));
1449 	if (*tl++ == rpc_msgdenied) {
1450 		if (*tl == rpc_mismatch) {
1451 			error = EOPNOTSUPP;
1452 		} else if ((nmp->nm_flag & NFSMNT_KERB) &&
1453 			   *tl++ == rpc_autherr) {
1454 			if (req->r_failed_auth == 0) {
1455 				req->r_failed_auth++;
1456 				req->r_mheadend->m_next = NULL;
1457 				m_freem(info->mrep);
1458 				info->mrep = NULL;
1459 				m_freem(req->r_mreq);
1460 				req->r_mreq = NULL;
1461 				return (ENEEDAUTH);
1462 			} else {
1463 				error = EAUTH;
1464 			}
1465 		} else {
1466 			error = EACCES;
1467 		}
1468 		m_freem(info->mrep);
1469 		info->mrep = NULL;
1470 		m_freem(req->r_mreq);
1471 		req->r_mreq = NULL;
1472 		kfree(req, M_NFSREQ);
1473 		info->req = NULL;
1474 		return (error);
1475 	}
1476 
1477 	/*
1478 	 * Grab any Kerberos verifier, otherwise just throw it away.
1479 	 */
1480 	verf_type = fxdr_unsigned(int, *tl++);
1481 	i = fxdr_unsigned(int32_t, *tl);
1482 	if ((nmp->nm_flag & NFSMNT_KERB) && verf_type == RPCAUTH_KERB4) {
1483 		error = nfs_savenickauth(nmp, req->r_cred, i, req->r_key,
1484 					 &info->md, &info->dpos, info->mrep);
1485 		if (error)
1486 			goto nfsmout;
1487 	} else if (i > 0) {
1488 		ERROROUT(nfsm_adv(info, nfsm_rndup(i)));
1489 	}
1490 	NULLOUT(tl = nfsm_dissect(info, NFSX_UNSIGNED));
1491 	/* 0 == ok */
1492 	if (*tl == 0) {
1493 		NULLOUT(tl = nfsm_dissect(info, NFSX_UNSIGNED));
1494 		if (*tl != 0) {
1495 			error = fxdr_unsigned(int, *tl);
1496 
1497 			/*
1498 			 * Does anyone even implement this?  Just impose
1499 			 * a 1-second delay.
1500 			 */
1501 			if ((nmp->nm_flag & NFSMNT_NFSV3) &&
1502 				error == NFSERR_TRYLATER) {
1503 				m_freem(info->mrep);
1504 				info->mrep = NULL;
1505 				error = 0;
1506 
1507 				tsleep((caddr_t)&lbolt, 0, "nqnfstry", 0);
1508 				return (EAGAIN);	/* goto tryagain */
1509 			}
1510 
1511 			/*
1512 			 * If the File Handle was stale, invalidate the
1513 			 * lookup cache, just in case.
1514 			 *
1515 			 * To avoid namecache<->vnode deadlocks we must
1516 			 * release the vnode lock if we hold it.
1517 			 */
1518 			if (error == ESTALE) {
1519 				struct vnode *vp = req->r_vp;
1520 				int ltype;
1521 
1522 				ltype = lockstatus(&vp->v_lock, curthread);
1523 				if (ltype == LK_EXCLUSIVE || ltype == LK_SHARED)
1524 					lockmgr(&vp->v_lock, LK_RELEASE);
1525 				cache_inval_vp(vp, CINV_CHILDREN);
1526 				if (ltype == LK_EXCLUSIVE || ltype == LK_SHARED)
1527 					lockmgr(&vp->v_lock, ltype);
1528 			}
1529 			if (nmp->nm_flag & NFSMNT_NFSV3) {
1530 				KKASSERT(*req->r_mrp == info->mrep);
1531 				KKASSERT(*req->r_mdp == info->md);
1532 				KKASSERT(*req->r_dposp == info->dpos);
1533 				error |= NFSERR_RETERR;
1534 			} else {
1535 				m_freem(info->mrep);
1536 				info->mrep = NULL;
1537 			}
1538 			m_freem(req->r_mreq);
1539 			req->r_mreq = NULL;
1540 			kfree(req, M_NFSREQ);
1541 			info->req = NULL;
1542 			return (error);
1543 		}
1544 
1545 		KKASSERT(*req->r_mrp == info->mrep);
1546 		KKASSERT(*req->r_mdp == info->md);
1547 		KKASSERT(*req->r_dposp == info->dpos);
1548 		m_freem(req->r_mreq);
1549 		req->r_mreq = NULL;
1550 		kfree(req, M_NFSREQ);
1551 		return (0);
1552 	}
1553 	m_freem(info->mrep);
1554 	info->mrep = NULL;
1555 	error = EPROTONOSUPPORT;
1556 nfsmout:
1557 	m_freem(req->r_mreq);
1558 	req->r_mreq = NULL;
1559 	kfree(req, M_NFSREQ);
1560 	info->req = NULL;
1561 	return (error);
1562 }
1563 
1564 #ifndef NFS_NOSERVER
1565 /*
1566  * Generate the rpc reply header
1567  * siz arg. is used to decide if adding a cluster is worthwhile
1568  */
1569 int
1570 nfs_rephead(int siz, struct nfsrv_descript *nd, struct nfssvc_sock *slp,
1571 	    int err, struct mbuf **mrq, struct mbuf **mbp, caddr_t *bposp)
1572 {
1573 	u_int32_t *tl;
1574 	struct nfsm_info info;
1575 
1576 	siz += RPC_REPLYSIZ;
1577 	info.mb = m_getl(max_hdr + siz, MB_WAIT, MT_DATA, M_PKTHDR, NULL);
1578 	info.mreq = info.mb;
1579 	info.mreq->m_pkthdr.len = 0;
1580 	/*
1581 	 * If this is not a cluster, try and leave leading space
1582 	 * for the lower level headers.
1583 	 */
1584 	if ((max_hdr + siz) < MINCLSIZE)
1585 		info.mreq->m_data += max_hdr;
1586 	tl = mtod(info.mreq, u_int32_t *);
1587 	info.mreq->m_len = 6 * NFSX_UNSIGNED;
1588 	info.bpos = ((caddr_t)tl) + info.mreq->m_len;
1589 	*tl++ = txdr_unsigned(nd->nd_retxid);
1590 	*tl++ = rpc_reply;
1591 	if (err == ERPCMISMATCH || (err & NFSERR_AUTHERR)) {
1592 		*tl++ = rpc_msgdenied;
1593 		if (err & NFSERR_AUTHERR) {
1594 			*tl++ = rpc_autherr;
1595 			*tl = txdr_unsigned(err & ~NFSERR_AUTHERR);
1596 			info.mreq->m_len -= NFSX_UNSIGNED;
1597 			info.bpos -= NFSX_UNSIGNED;
1598 		} else {
1599 			*tl++ = rpc_mismatch;
1600 			*tl++ = txdr_unsigned(RPC_VER2);
1601 			*tl = txdr_unsigned(RPC_VER2);
1602 		}
1603 	} else {
1604 		*tl++ = rpc_msgaccepted;
1605 
1606 		/*
1607 		 * For Kerberos authentication, we must send the nickname
1608 		 * verifier back, otherwise just RPCAUTH_NULL.
1609 		 */
1610 		if (nd->nd_flag & ND_KERBFULL) {
1611 		    struct nfsuid *nuidp;
1612 		    struct timeval ktvout;
1613 
1614 		    for (nuidp = NUIDHASH(slp, nd->nd_cr.cr_uid)->lh_first;
1615 			nuidp != NULL; nuidp = nuidp->nu_hash.le_next) {
1616 			if (nuidp->nu_cr.cr_uid == nd->nd_cr.cr_uid &&
1617 			    (!nd->nd_nam2 || netaddr_match(NU_NETFAM(nuidp),
1618 			     &nuidp->nu_haddr, nd->nd_nam2)))
1619 			    break;
1620 		    }
1621 		    if (nuidp) {
1622 			/*
1623 			 * Encrypt the timestamp in ecb mode using the
1624 			 * session key.
1625 			 */
1626 #ifdef NFSKERB
1627 			XXX
1628 #else
1629 			ktvout.tv_sec = 0;
1630 			ktvout.tv_usec = 0;
1631 #endif
1632 
1633 			*tl++ = rpc_auth_kerb;
1634 			*tl++ = txdr_unsigned(3 * NFSX_UNSIGNED);
1635 			*tl = ktvout.tv_sec;
1636 			tl = nfsm_build(&info, 3 * NFSX_UNSIGNED);
1637 			*tl++ = ktvout.tv_usec;
1638 			*tl++ = txdr_unsigned(nuidp->nu_cr.cr_uid);
1639 		    } else {
1640 			*tl++ = 0;
1641 			*tl++ = 0;
1642 		    }
1643 		} else {
1644 			*tl++ = 0;
1645 			*tl++ = 0;
1646 		}
1647 		switch (err) {
1648 		case EPROGUNAVAIL:
1649 			*tl = txdr_unsigned(RPC_PROGUNAVAIL);
1650 			break;
1651 		case EPROGMISMATCH:
1652 			*tl = txdr_unsigned(RPC_PROGMISMATCH);
1653 			tl = nfsm_build(&info, 2 * NFSX_UNSIGNED);
1654 			*tl++ = txdr_unsigned(2);
1655 			*tl = txdr_unsigned(3);
1656 			break;
1657 		case EPROCUNAVAIL:
1658 			*tl = txdr_unsigned(RPC_PROCUNAVAIL);
1659 			break;
1660 		case EBADRPC:
1661 			*tl = txdr_unsigned(RPC_GARBAGE);
1662 			break;
1663 		default:
1664 			*tl = 0;
1665 			if (err != NFSERR_RETVOID) {
1666 				tl = nfsm_build(&info, NFSX_UNSIGNED);
1667 				if (err)
1668 				    *tl = txdr_unsigned(nfsrv_errmap(nd, err));
1669 				else
1670 				    *tl = 0;
1671 			}
1672 			break;
1673 		};
1674 	}
1675 
1676 	if (mrq != NULL)
1677 	    *mrq = info.mreq;
1678 	*mbp = info.mb;
1679 	*bposp = info.bpos;
1680 	if (err != 0 && err != NFSERR_RETVOID)
1681 		nfsstats.srvrpc_errs++;
1682 	return (0);
1683 }
1684 
1685 
1686 #endif /* NFS_NOSERVER */
1687 
1688 /*
1689  * Nfs timer routine.
1690  *
1691  * Scan the nfsreq list and retranmit any requests that have timed out
1692  * To avoid retransmission attempts on STREAM sockets (in the future) make
1693  * sure to set the r_retry field to 0 (implies nm_retry == 0).
1694  *
1695  * Requests with attached responses, terminated requests, and
1696  * locked requests are ignored.  Locked requests will be picked up
1697  * in a later timer call.
1698  */
1699 void
1700 nfs_timer_callout(void *arg /* never used */)
1701 {
1702 	struct nfsmount *nmp;
1703 	struct nfsreq *req;
1704 #ifndef NFS_NOSERVER
1705 	struct nfssvc_sock *slp;
1706 	u_quad_t cur_usec;
1707 #endif /* NFS_NOSERVER */
1708 
1709 	lwkt_gettoken(&nfs_token);
1710 	TAILQ_FOREACH(nmp, &nfs_mountq, nm_entry) {
1711 		lwkt_gettoken(&nmp->nm_token);
1712 		TAILQ_FOREACH(req, &nmp->nm_reqq, r_chain) {
1713 			KKASSERT(nmp == req->r_nmp);
1714 			if (req->r_mrep)
1715 				continue;
1716 			if (req->r_flags & (R_SOFTTERM | R_LOCKED))
1717 				continue;
1718 
1719 			/*
1720 			 * Handle timeout/retry.  Be sure to process r_mrep
1721 			 * for async requests that completed while we had
1722 			 * the request locked or they will hang in the reqq
1723 			 * forever.
1724 			 */
1725 			req->r_flags |= R_LOCKED;
1726 			if (nfs_sigintr(nmp, req, req->r_td)) {
1727 				nfs_softterm(req, 1);
1728 				req->r_flags &= ~R_LOCKED;
1729 			} else {
1730 				nfs_timer_req(req);
1731 				if (req->r_flags & R_ASYNC) {
1732 					if (req->r_mrep)
1733 						nfs_hardterm(req, 1);
1734 					req->r_flags &= ~R_LOCKED;
1735 					nfssvc_iod_reader_wakeup(nmp);
1736 				} else {
1737 					req->r_flags &= ~R_LOCKED;
1738 				}
1739 			}
1740 			if (req->r_flags & R_WANTED) {
1741 				req->r_flags &= ~R_WANTED;
1742 				wakeup(req);
1743 			}
1744 		}
1745 		lwkt_reltoken(&nmp->nm_token);
1746 	}
1747 #ifndef NFS_NOSERVER
1748 
1749 	/*
1750 	 * Scan the write gathering queues for writes that need to be
1751 	 * completed now.
1752 	 */
1753 	cur_usec = nfs_curusec();
1754 
1755 	TAILQ_FOREACH(slp, &nfssvc_sockhead, ns_chain) {
1756 		/* XXX race against removal */
1757 		if (lwkt_trytoken(&slp->ns_token)) {
1758 			if (slp->ns_tq.lh_first &&
1759 			    (slp->ns_tq.lh_first->nd_time <= cur_usec)) {
1760 				nfsrv_wakenfsd(slp, 1);
1761 			}
1762 			lwkt_reltoken(&slp->ns_token);
1763 		}
1764 	}
1765 #endif /* NFS_NOSERVER */
1766 
1767 	callout_reset(&nfs_timer_handle, nfs_ticks, nfs_timer_callout, NULL);
1768 	lwkt_reltoken(&nfs_token);
1769 }
1770 
1771 static
1772 void
1773 nfs_timer_req(struct nfsreq *req)
1774 {
1775 	struct thread *td = &thread0; /* XXX for creds, will break if sleep */
1776 	struct nfsmount *nmp = req->r_nmp;
1777 	struct mbuf *m;
1778 	struct socket *so;
1779 	int timeo;
1780 	int error;
1781 
1782 	/*
1783 	 * rtt ticks and timeout calculation.  Return if the timeout
1784 	 * has not been reached yet, unless the packet is flagged
1785 	 * for an immediate send.
1786 	 *
1787 	 * The mean rtt doesn't help when we get random I/Os, we have
1788 	 * to multiply by fairly large numbers.
1789 	 */
1790 	if (req->r_rtt >= 0) {
1791 		/*
1792 		 * Calculate the timeout to test against.
1793 		 */
1794 		req->r_rtt++;
1795 		if (nmp->nm_flag & NFSMNT_DUMBTIMR) {
1796 			timeo = nmp->nm_timeo << NFS_RTT_SCALE_BITS;
1797 		} else if (req->r_flags & R_TIMING) {
1798 			timeo = NFS_SRTT(req) + NFS_SDRTT(req);
1799 		} else {
1800 			timeo = nmp->nm_timeo << NFS_RTT_SCALE_BITS;
1801 		}
1802 		timeo *= multt[req->r_procnum];
1803 		/* timeo is still scaled by SCALE_BITS */
1804 
1805 #define NFSFS	(NFS_RTT_SCALE * NFS_HZ)
1806 		if (req->r_flags & R_TIMING) {
1807 			static long last_time;
1808 			if (nfs_showrtt && last_time != time_second) {
1809 				kprintf("rpccmd %d NFS SRTT %d SDRTT %d "
1810 					"timeo %d.%03d\n",
1811 					proct[req->r_procnum],
1812 					NFS_SRTT(req), NFS_SDRTT(req),
1813 					timeo / NFSFS,
1814 					timeo % NFSFS * 1000 /  NFSFS);
1815 				last_time = time_second;
1816 			}
1817 		}
1818 #undef NFSFS
1819 
1820 		/*
1821 		 * deal with nfs_timer jitter.
1822 		 */
1823 		timeo = (timeo >> NFS_RTT_SCALE_BITS) + 1;
1824 		if (timeo < 2)
1825 			timeo = 2;
1826 
1827 		if (nmp->nm_timeouts > 0)
1828 			timeo *= nfs_backoff[nmp->nm_timeouts - 1];
1829 		if (timeo > NFS_MAXTIMEO)
1830 			timeo = NFS_MAXTIMEO;
1831 		if (req->r_rtt <= timeo) {
1832 			if ((req->r_flags & R_NEEDSXMIT) == 0)
1833 				return;
1834 		} else if (nmp->nm_timeouts < 8) {
1835 			nmp->nm_timeouts++;
1836 		}
1837 	}
1838 
1839 	/*
1840 	 * Check for server not responding
1841 	 */
1842 	if ((req->r_flags & R_TPRINTFMSG) == 0 &&
1843 	     req->r_rexmit > nmp->nm_deadthresh) {
1844 		nfs_msg(req->r_td, nmp->nm_mountp->mnt_stat.f_mntfromname,
1845 			"not responding");
1846 		req->r_flags |= R_TPRINTFMSG;
1847 	}
1848 	if (req->r_rexmit >= req->r_retry) {	/* too many */
1849 		nfsstats.rpctimeouts++;
1850 		nfs_softterm(req, 1);
1851 		return;
1852 	}
1853 
1854 	/*
1855 	 * Generally disable retransmission on reliable sockets,
1856 	 * unless the request is flagged for immediate send.
1857 	 */
1858 	if (nmp->nm_sotype != SOCK_DGRAM) {
1859 		if (++req->r_rexmit > NFS_MAXREXMIT)
1860 			req->r_rexmit = NFS_MAXREXMIT;
1861 		if ((req->r_flags & R_NEEDSXMIT) == 0)
1862 			return;
1863 	}
1864 
1865 	/*
1866 	 * Stop here if we do not have a socket!
1867 	 */
1868 	if ((so = nmp->nm_so) == NULL)
1869 		return;
1870 
1871 	/*
1872 	 * If there is enough space and the window allows.. resend it.
1873 	 *
1874 	 * r_rtt is left intact in case we get an answer after the
1875 	 * retry that was a reply to the original packet.
1876 	 *
1877 	 * NOTE: so_pru_send()
1878 	 */
1879 	if (ssb_space(&so->so_snd) >= req->r_mreq->m_pkthdr.len &&
1880 	    (req->r_flags & (R_SENT | R_NEEDSXMIT)) &&
1881 	   (m = m_copym(req->r_mreq, 0, M_COPYALL, MB_DONTWAIT))){
1882 		if ((nmp->nm_flag & NFSMNT_NOCONN) == 0)
1883 		    error = so_pru_send(so, 0, m, NULL, NULL, td);
1884 		else
1885 		    error = so_pru_send(so, 0, m, nmp->nm_nam, NULL, td);
1886 		if (error) {
1887 			if (NFSIGNORE_SOERROR(nmp->nm_soflags, error))
1888 				so->so_error = 0;
1889 			req->r_flags |= R_NEEDSXMIT;
1890 		} else if (req->r_mrep == NULL) {
1891 			/*
1892 			 * Iff first send, start timing
1893 			 * else turn timing off, backoff timer
1894 			 * and divide congestion window by 2.
1895 			 *
1896 			 * It is possible for the so_pru_send() to
1897 			 * block and for us to race a reply so we
1898 			 * only do this if the reply field has not
1899 			 * been filled in.  R_LOCKED will prevent
1900 			 * the request from being ripped out from under
1901 			 * us entirely.
1902 			 *
1903 			 * Record the last resent procnum to aid us
1904 			 * in duplicate detection on receive.
1905 			 */
1906 			if ((req->r_flags & R_NEEDSXMIT) == 0) {
1907 				if (nfs_showrexmit)
1908 					kprintf("X");
1909 				if (++req->r_rexmit > NFS_MAXREXMIT)
1910 					req->r_rexmit = NFS_MAXREXMIT;
1911 				nmp->nm_maxasync_scaled >>= 1;
1912 				if (nmp->nm_maxasync_scaled < NFS_MINASYNC_SCALED)
1913 					nmp->nm_maxasync_scaled = NFS_MINASYNC_SCALED;
1914 				nfsstats.rpcretries++;
1915 				nmp->nm_lastreprocnum = req->r_procnum;
1916 			} else {
1917 				req->r_flags |= R_SENT;
1918 				req->r_flags &= ~R_NEEDSXMIT;
1919 			}
1920 		}
1921 	}
1922 }
1923 
1924 /*
1925  * Mark all of an nfs mount's outstanding requests with R_SOFTTERM and
1926  * wait for all requests to complete. This is used by forced unmounts
1927  * to terminate any outstanding RPCs.
1928  *
1929  * Locked requests cannot be canceled but will be marked for
1930  * soft-termination.
1931  */
1932 int
1933 nfs_nmcancelreqs(struct nfsmount *nmp)
1934 {
1935 	struct nfsreq *req;
1936 	int i;
1937 
1938 	crit_enter();
1939 	TAILQ_FOREACH(req, &nmp->nm_reqq, r_chain) {
1940 		if (req->r_mrep != NULL || (req->r_flags & R_SOFTTERM))
1941 			continue;
1942 		nfs_softterm(req, 0);
1943 	}
1944 	/* XXX  the other two queues as well */
1945 	crit_exit();
1946 
1947 	for (i = 0; i < 30; i++) {
1948 		crit_enter();
1949 		TAILQ_FOREACH(req, &nmp->nm_reqq, r_chain) {
1950 			if (nmp == req->r_nmp)
1951 				break;
1952 		}
1953 		crit_exit();
1954 		if (req == NULL)
1955 			return (0);
1956 		tsleep(&lbolt, 0, "nfscancel", 0);
1957 	}
1958 	return (EBUSY);
1959 }
1960 
1961 /*
1962  * Soft-terminate a request, effectively marking it as failed.
1963  *
1964  * Must be called from within a critical section.
1965  */
1966 static void
1967 nfs_softterm(struct nfsreq *rep, int islocked)
1968 {
1969 	rep->r_flags |= R_SOFTTERM;
1970 	nfs_hardterm(rep, islocked);
1971 }
1972 
1973 /*
1974  * Hard-terminate a request, typically after getting a response.
1975  *
1976  * The state machine can still decide to re-issue it later if necessary.
1977  *
1978  * Must be called from within a critical section.
1979  */
1980 static void
1981 nfs_hardterm(struct nfsreq *rep, int islocked)
1982 {
1983 	struct nfsmount *nmp = rep->r_nmp;
1984 
1985 	/*
1986 	 * The nm_send count is decremented now to avoid deadlocks
1987 	 * when the process in soreceive() hasn't yet managed to send
1988 	 * its own request.
1989 	 */
1990 	if (rep->r_flags & R_SENT) {
1991 		rep->r_flags &= ~R_SENT;
1992 	}
1993 
1994 	/*
1995 	 * If we locked the request or nobody else has locked the request,
1996 	 * and the request is async, we can move it to the reader thread's
1997 	 * queue now and fix up the state.
1998 	 *
1999 	 * If we locked the request or nobody else has locked the request,
2000 	 * we can wake up anyone blocked waiting for a response on the
2001 	 * request.
2002 	 */
2003 	if (islocked || (rep->r_flags & R_LOCKED) == 0) {
2004 		if ((rep->r_flags & (R_ONREQQ | R_ASYNC)) ==
2005 		    (R_ONREQQ | R_ASYNC)) {
2006 			rep->r_flags &= ~R_ONREQQ;
2007 			TAILQ_REMOVE(&nmp->nm_reqq, rep, r_chain);
2008 			--nmp->nm_reqqlen;
2009 			TAILQ_INSERT_TAIL(&nmp->nm_reqrxq, rep, r_chain);
2010 			KKASSERT(rep->r_info->state == NFSM_STATE_TRY ||
2011 				 rep->r_info->state == NFSM_STATE_WAITREPLY);
2012 			rep->r_info->state = NFSM_STATE_PROCESSREPLY;
2013 			nfssvc_iod_reader_wakeup(nmp);
2014 			if (TAILQ_FIRST(&nmp->nm_bioq) &&
2015 			    nmp->nm_reqqlen <= nfs_maxasyncbio * 2 / 3) {
2016 				nfssvc_iod_writer_wakeup(nmp);
2017 			}
2018 		}
2019 		mtx_abort_ex_link(&nmp->nm_rxlock, &rep->r_link);
2020 	}
2021 }
2022 
2023 /*
2024  * Test for a termination condition pending on the process.
2025  * This is used for NFSMNT_INT mounts.
2026  */
2027 int
2028 nfs_sigintr(struct nfsmount *nmp, struct nfsreq *rep, struct thread *td)
2029 {
2030 	sigset_t tmpset;
2031 	struct proc *p;
2032 	struct lwp *lp;
2033 
2034 	if (rep && (rep->r_flags & R_SOFTTERM))
2035 		return (EINTR);
2036 	/* Terminate all requests while attempting a forced unmount. */
2037 	if (nmp->nm_mountp->mnt_kern_flag & MNTK_UNMOUNTF)
2038 		return (EINTR);
2039 	if (!(nmp->nm_flag & NFSMNT_INT))
2040 		return (0);
2041 	/* td might be NULL YYY */
2042 	if (td == NULL || (p = td->td_proc) == NULL)
2043 		return (0);
2044 
2045 	lp = td->td_lwp;
2046 	tmpset = lwp_sigpend(lp);
2047 	SIGSETNAND(tmpset, lp->lwp_sigmask);
2048 	SIGSETNAND(tmpset, p->p_sigignore);
2049 	if (SIGNOTEMPTY(tmpset) && NFSINT_SIGMASK(tmpset))
2050 		return (EINTR);
2051 
2052 	return (0);
2053 }
2054 
2055 /*
2056  * Lock a socket against others.
2057  * Necessary for STREAM sockets to ensure you get an entire rpc request/reply
2058  * and also to avoid race conditions between the processes with nfs requests
2059  * in progress when a reconnect is necessary.
2060  */
2061 int
2062 nfs_sndlock(struct nfsmount *nmp, struct nfsreq *rep)
2063 {
2064 	mtx_t mtx = &nmp->nm_txlock;
2065 	struct thread *td;
2066 	int slptimeo;
2067 	int slpflag;
2068 	int error;
2069 
2070 	slpflag = 0;
2071 	slptimeo = 0;
2072 	td = rep ? rep->r_td : NULL;
2073 	if (nmp->nm_flag & NFSMNT_INT)
2074 		slpflag = PCATCH;
2075 
2076 	while ((error = mtx_lock_ex_try(mtx)) != 0) {
2077 		if (nfs_sigintr(nmp, rep, td)) {
2078 			error = EINTR;
2079 			break;
2080 		}
2081 		error = mtx_lock_ex(mtx, "nfsndlck", slpflag, slptimeo);
2082 		if (error == 0)
2083 			break;
2084 		if (slpflag == PCATCH) {
2085 			slpflag = 0;
2086 			slptimeo = 2 * hz;
2087 		}
2088 	}
2089 	/* Always fail if our request has been cancelled. */
2090 	if (rep && (rep->r_flags & R_SOFTTERM)) {
2091 		if (error == 0)
2092 			mtx_unlock(mtx);
2093 		error = EINTR;
2094 	}
2095 	return (error);
2096 }
2097 
2098 /*
2099  * Unlock the stream socket for others.
2100  */
2101 void
2102 nfs_sndunlock(struct nfsmount *nmp)
2103 {
2104 	mtx_unlock(&nmp->nm_txlock);
2105 }
2106 
2107 /*
2108  * Lock the receiver side of the socket.
2109  *
2110  * rep may be NULL.
2111  */
2112 static int
2113 nfs_rcvlock(struct nfsmount *nmp, struct nfsreq *rep)
2114 {
2115 	mtx_t mtx = &nmp->nm_rxlock;
2116 	int slpflag;
2117 	int slptimeo;
2118 	int error;
2119 
2120 	/*
2121 	 * Unconditionally check for completion in case another nfsiod
2122 	 * get the packet while the caller was blocked, before the caller
2123 	 * called us.  Packet reception is handled by mainline code which
2124 	 * is protected by the BGL at the moment.
2125 	 *
2126 	 * We do not strictly need the second check just before the
2127 	 * tsleep(), but it's good defensive programming.
2128 	 */
2129 	if (rep && rep->r_mrep != NULL)
2130 		return (EALREADY);
2131 
2132 	if (nmp->nm_flag & NFSMNT_INT)
2133 		slpflag = PCATCH;
2134 	else
2135 		slpflag = 0;
2136 	slptimeo = 0;
2137 
2138 	while ((error = mtx_lock_ex_try(mtx)) != 0) {
2139 		if (nfs_sigintr(nmp, rep, (rep ? rep->r_td : NULL))) {
2140 			error = EINTR;
2141 			break;
2142 		}
2143 		if (rep && rep->r_mrep != NULL) {
2144 			error = EALREADY;
2145 			break;
2146 		}
2147 
2148 		/*
2149 		 * NOTE: can return ENOLCK, but in that case rep->r_mrep
2150 		 *       will already be set.
2151 		 */
2152 		if (rep) {
2153 			error = mtx_lock_ex_link(mtx, &rep->r_link,
2154 						 "nfsrcvlk",
2155 						 slpflag, slptimeo);
2156 		} else {
2157 			error = mtx_lock_ex(mtx, "nfsrcvlk", slpflag, slptimeo);
2158 		}
2159 		if (error == 0)
2160 			break;
2161 
2162 		/*
2163 		 * If our reply was recieved while we were sleeping,
2164 		 * then just return without taking the lock to avoid a
2165 		 * situation where a single iod could 'capture' the
2166 		 * recieve lock.
2167 		 */
2168 		if (rep && rep->r_mrep != NULL) {
2169 			error = EALREADY;
2170 			break;
2171 		}
2172 		if (slpflag == PCATCH) {
2173 			slpflag = 0;
2174 			slptimeo = 2 * hz;
2175 		}
2176 	}
2177 	if (error == 0) {
2178 		if (rep && rep->r_mrep != NULL) {
2179 			error = EALREADY;
2180 			mtx_unlock(mtx);
2181 		}
2182 	}
2183 	return (error);
2184 }
2185 
2186 /*
2187  * Unlock the stream socket for others.
2188  */
2189 static void
2190 nfs_rcvunlock(struct nfsmount *nmp)
2191 {
2192 	mtx_unlock(&nmp->nm_rxlock);
2193 }
2194 
2195 /*
2196  * nfs_realign:
2197  *
2198  * Check for badly aligned mbuf data and realign by copying the unaligned
2199  * portion of the data into a new mbuf chain and freeing the portions
2200  * of the old chain that were replaced.
2201  *
2202  * We cannot simply realign the data within the existing mbuf chain
2203  * because the underlying buffers may contain other rpc commands and
2204  * we cannot afford to overwrite them.
2205  *
2206  * We would prefer to avoid this situation entirely.  The situation does
2207  * not occur with NFS/UDP and is supposed to only occassionally occur
2208  * with TCP.  Use vfs.nfs.realign_count and realign_test to check this.
2209  *
2210  * NOTE!  MB_DONTWAIT cannot be used here.  The mbufs must be acquired
2211  *	  because the rpc request OR reply cannot be thrown away.  TCP NFS
2212  *	  mounts do not retry their RPCs unless the TCP connection itself
2213  *	  is dropped so throwing away a RPC will basically cause the NFS
2214  *	  operation to lockup indefinitely.
2215  */
2216 static void
2217 nfs_realign(struct mbuf **pm, int hsiz)
2218 {
2219 	struct mbuf *m;
2220 	struct mbuf *n = NULL;
2221 
2222 	/*
2223 	 * Check for misalignemnt
2224 	 */
2225 	++nfs_realign_test;
2226 	while ((m = *pm) != NULL) {
2227 		if ((m->m_len & 0x3) || (mtod(m, intptr_t) & 0x3))
2228 			break;
2229 		pm = &m->m_next;
2230 	}
2231 
2232 	/*
2233 	 * If misalignment found make a completely new copy.
2234 	 */
2235 	if (m) {
2236 		++nfs_realign_count;
2237 		n = m_dup_data(m, MB_WAIT);
2238 		m_freem(*pm);
2239 		*pm = n;
2240 	}
2241 }
2242 
2243 #ifndef NFS_NOSERVER
2244 
2245 /*
2246  * Parse an RPC request
2247  * - verify it
2248  * - fill in the cred struct.
2249  */
2250 int
2251 nfs_getreq(struct nfsrv_descript *nd, struct nfsd *nfsd, int has_header)
2252 {
2253 	int len, i;
2254 	u_int32_t *tl;
2255 	struct uio uio;
2256 	struct iovec iov;
2257 	caddr_t cp;
2258 	u_int32_t nfsvers, auth_type;
2259 	uid_t nickuid;
2260 	int error = 0, ticklen;
2261 	struct nfsuid *nuidp;
2262 	struct timeval tvin, tvout;
2263 	struct nfsm_info info;
2264 #if 0				/* until encrypted keys are implemented */
2265 	NFSKERBKEYSCHED_T keys;	/* stores key schedule */
2266 #endif
2267 
2268 	info.mrep = nd->nd_mrep;
2269 	info.md = nd->nd_md;
2270 	info.dpos = nd->nd_dpos;
2271 
2272 	if (has_header) {
2273 		NULLOUT(tl = nfsm_dissect(&info, 10 * NFSX_UNSIGNED));
2274 		nd->nd_retxid = fxdr_unsigned(u_int32_t, *tl++);
2275 		if (*tl++ != rpc_call) {
2276 			m_freem(info.mrep);
2277 			return (EBADRPC);
2278 		}
2279 	} else {
2280 		NULLOUT(tl = nfsm_dissect(&info, 8 * NFSX_UNSIGNED));
2281 	}
2282 	nd->nd_repstat = 0;
2283 	nd->nd_flag = 0;
2284 	if (*tl++ != rpc_vers) {
2285 		nd->nd_repstat = ERPCMISMATCH;
2286 		nd->nd_procnum = NFSPROC_NOOP;
2287 		return (0);
2288 	}
2289 	if (*tl != nfs_prog) {
2290 		nd->nd_repstat = EPROGUNAVAIL;
2291 		nd->nd_procnum = NFSPROC_NOOP;
2292 		return (0);
2293 	}
2294 	tl++;
2295 	nfsvers = fxdr_unsigned(u_int32_t, *tl++);
2296 	if (nfsvers < NFS_VER2 || nfsvers > NFS_VER3) {
2297 		nd->nd_repstat = EPROGMISMATCH;
2298 		nd->nd_procnum = NFSPROC_NOOP;
2299 		return (0);
2300 	}
2301 	if (nfsvers == NFS_VER3)
2302 		nd->nd_flag = ND_NFSV3;
2303 	nd->nd_procnum = fxdr_unsigned(u_int32_t, *tl++);
2304 	if (nd->nd_procnum == NFSPROC_NULL)
2305 		return (0);
2306 	if (nd->nd_procnum >= NFS_NPROCS ||
2307 		(nd->nd_procnum >= NQNFSPROC_GETLEASE) ||
2308 		(!nd->nd_flag && nd->nd_procnum > NFSV2PROC_STATFS)) {
2309 		nd->nd_repstat = EPROCUNAVAIL;
2310 		nd->nd_procnum = NFSPROC_NOOP;
2311 		return (0);
2312 	}
2313 	if ((nd->nd_flag & ND_NFSV3) == 0)
2314 		nd->nd_procnum = nfsv3_procid[nd->nd_procnum];
2315 	auth_type = *tl++;
2316 	len = fxdr_unsigned(int, *tl++);
2317 	if (len < 0 || len > RPCAUTH_MAXSIZ) {
2318 		m_freem(info.mrep);
2319 		return (EBADRPC);
2320 	}
2321 
2322 	nd->nd_flag &= ~ND_KERBAUTH;
2323 	/*
2324 	 * Handle auth_unix or auth_kerb.
2325 	 */
2326 	if (auth_type == rpc_auth_unix) {
2327 		len = fxdr_unsigned(int, *++tl);
2328 		if (len < 0 || len > NFS_MAXNAMLEN) {
2329 			m_freem(info.mrep);
2330 			return (EBADRPC);
2331 		}
2332 		ERROROUT(nfsm_adv(&info, nfsm_rndup(len)));
2333 		NULLOUT(tl = nfsm_dissect(&info, 3 * NFSX_UNSIGNED));
2334 		bzero((caddr_t)&nd->nd_cr, sizeof (struct ucred));
2335 		nd->nd_cr.cr_ref = 1;
2336 		nd->nd_cr.cr_uid = fxdr_unsigned(uid_t, *tl++);
2337 		nd->nd_cr.cr_ruid = nd->nd_cr.cr_svuid = nd->nd_cr.cr_uid;
2338 		nd->nd_cr.cr_gid = fxdr_unsigned(gid_t, *tl++);
2339 		nd->nd_cr.cr_rgid = nd->nd_cr.cr_svgid = nd->nd_cr.cr_gid;
2340 		len = fxdr_unsigned(int, *tl);
2341 		if (len < 0 || len > RPCAUTH_UNIXGIDS) {
2342 			m_freem(info.mrep);
2343 			return (EBADRPC);
2344 		}
2345 		NULLOUT(tl = nfsm_dissect(&info, (len + 2) * NFSX_UNSIGNED));
2346 		for (i = 1; i <= len; i++)
2347 		    if (i < NGROUPS)
2348 			nd->nd_cr.cr_groups[i] = fxdr_unsigned(gid_t, *tl++);
2349 		    else
2350 			tl++;
2351 		nd->nd_cr.cr_ngroups = (len >= NGROUPS) ? NGROUPS : (len + 1);
2352 		if (nd->nd_cr.cr_ngroups > 1)
2353 		    nfsrvw_sort(nd->nd_cr.cr_groups, nd->nd_cr.cr_ngroups);
2354 		len = fxdr_unsigned(int, *++tl);
2355 		if (len < 0 || len > RPCAUTH_MAXSIZ) {
2356 			m_freem(info.mrep);
2357 			return (EBADRPC);
2358 		}
2359 		if (len > 0) {
2360 			ERROROUT(nfsm_adv(&info, nfsm_rndup(len)));
2361 		}
2362 	} else if (auth_type == rpc_auth_kerb) {
2363 		switch (fxdr_unsigned(int, *tl++)) {
2364 		case RPCAKN_FULLNAME:
2365 			ticklen = fxdr_unsigned(int, *tl);
2366 			*((u_int32_t *)nfsd->nfsd_authstr) = *tl;
2367 			uio.uio_resid = nfsm_rndup(ticklen) + NFSX_UNSIGNED;
2368 			nfsd->nfsd_authlen = uio.uio_resid + NFSX_UNSIGNED;
2369 			if (uio.uio_resid > (len - 2 * NFSX_UNSIGNED)) {
2370 				m_freem(info.mrep);
2371 				return (EBADRPC);
2372 			}
2373 			uio.uio_offset = 0;
2374 			uio.uio_iov = &iov;
2375 			uio.uio_iovcnt = 1;
2376 			uio.uio_segflg = UIO_SYSSPACE;
2377 			iov.iov_base = (caddr_t)&nfsd->nfsd_authstr[4];
2378 			iov.iov_len = RPCAUTH_MAXSIZ - 4;
2379 			ERROROUT(nfsm_mtouio(&info, &uio, uio.uio_resid));
2380 			NULLOUT(tl = nfsm_dissect(&info, 2 * NFSX_UNSIGNED));
2381 			if (*tl++ != rpc_auth_kerb ||
2382 				fxdr_unsigned(int, *tl) != 4 * NFSX_UNSIGNED) {
2383 				kprintf("Bad kerb verifier\n");
2384 				nd->nd_repstat = (NFSERR_AUTHERR|AUTH_BADVERF);
2385 				nd->nd_procnum = NFSPROC_NOOP;
2386 				return (0);
2387 			}
2388 			NULLOUT(cp = nfsm_dissect(&info, 4 * NFSX_UNSIGNED));
2389 			tl = (u_int32_t *)cp;
2390 			if (fxdr_unsigned(int, *tl) != RPCAKN_FULLNAME) {
2391 				kprintf("Not fullname kerb verifier\n");
2392 				nd->nd_repstat = (NFSERR_AUTHERR|AUTH_BADVERF);
2393 				nd->nd_procnum = NFSPROC_NOOP;
2394 				return (0);
2395 			}
2396 			cp += NFSX_UNSIGNED;
2397 			bcopy(cp, nfsd->nfsd_verfstr, 3 * NFSX_UNSIGNED);
2398 			nfsd->nfsd_verflen = 3 * NFSX_UNSIGNED;
2399 			nd->nd_flag |= ND_KERBFULL;
2400 			nfsd->nfsd_flag |= NFSD_NEEDAUTH;
2401 			break;
2402 		case RPCAKN_NICKNAME:
2403 			if (len != 2 * NFSX_UNSIGNED) {
2404 				kprintf("Kerb nickname short\n");
2405 				nd->nd_repstat = (NFSERR_AUTHERR|AUTH_BADCRED);
2406 				nd->nd_procnum = NFSPROC_NOOP;
2407 				return (0);
2408 			}
2409 			nickuid = fxdr_unsigned(uid_t, *tl);
2410 			NULLOUT(tl = nfsm_dissect(&info, 2 * NFSX_UNSIGNED));
2411 			if (*tl++ != rpc_auth_kerb ||
2412 				fxdr_unsigned(int, *tl) != 3 * NFSX_UNSIGNED) {
2413 				kprintf("Kerb nick verifier bad\n");
2414 				nd->nd_repstat = (NFSERR_AUTHERR|AUTH_BADVERF);
2415 				nd->nd_procnum = NFSPROC_NOOP;
2416 				return (0);
2417 			}
2418 			NULLOUT(tl = nfsm_dissect(&info, 3 * NFSX_UNSIGNED));
2419 			tvin.tv_sec = *tl++;
2420 			tvin.tv_usec = *tl;
2421 
2422 			for (nuidp = NUIDHASH(nfsd->nfsd_slp,nickuid)->lh_first;
2423 			    nuidp != NULL; nuidp = nuidp->nu_hash.le_next) {
2424 				if (nuidp->nu_cr.cr_uid == nickuid &&
2425 				    (!nd->nd_nam2 ||
2426 				     netaddr_match(NU_NETFAM(nuidp),
2427 				      &nuidp->nu_haddr, nd->nd_nam2)))
2428 					break;
2429 			}
2430 			if (!nuidp) {
2431 				nd->nd_repstat =
2432 					(NFSERR_AUTHERR|AUTH_REJECTCRED);
2433 				nd->nd_procnum = NFSPROC_NOOP;
2434 				return (0);
2435 			}
2436 
2437 			/*
2438 			 * Now, decrypt the timestamp using the session key
2439 			 * and validate it.
2440 			 */
2441 #ifdef NFSKERB
2442 			XXX
2443 #else
2444 			tvout.tv_sec = 0;
2445 			tvout.tv_usec = 0;
2446 #endif
2447 
2448 			tvout.tv_sec = fxdr_unsigned(long, tvout.tv_sec);
2449 			tvout.tv_usec = fxdr_unsigned(long, tvout.tv_usec);
2450 			if (nuidp->nu_expire < time_second ||
2451 			    nuidp->nu_timestamp.tv_sec > tvout.tv_sec ||
2452 			    (nuidp->nu_timestamp.tv_sec == tvout.tv_sec &&
2453 			     nuidp->nu_timestamp.tv_usec > tvout.tv_usec)) {
2454 				nuidp->nu_expire = 0;
2455 				nd->nd_repstat =
2456 				    (NFSERR_AUTHERR|AUTH_REJECTVERF);
2457 				nd->nd_procnum = NFSPROC_NOOP;
2458 				return (0);
2459 			}
2460 			nfsrv_setcred(&nuidp->nu_cr, &nd->nd_cr);
2461 			nd->nd_flag |= ND_KERBNICK;
2462 			break;
2463 		}
2464 	} else {
2465 		nd->nd_repstat = (NFSERR_AUTHERR | AUTH_REJECTCRED);
2466 		nd->nd_procnum = NFSPROC_NOOP;
2467 		return (0);
2468 	}
2469 
2470 	nd->nd_md = info.md;
2471 	nd->nd_dpos = info.dpos;
2472 	return (0);
2473 nfsmout:
2474 	return (error);
2475 }
2476 
2477 #endif
2478 
2479 /*
2480  * Send a message to the originating process's terminal.  The thread and/or
2481  * process may be NULL.  YYY the thread should not be NULL but there may
2482  * still be some uio_td's that are still being passed as NULL through to
2483  * nfsm_request().
2484  */
2485 static int
2486 nfs_msg(struct thread *td, char *server, char *msg)
2487 {
2488 	tpr_t tpr;
2489 
2490 	if (td && td->td_proc)
2491 		tpr = tprintf_open(td->td_proc);
2492 	else
2493 		tpr = NULL;
2494 	tprintf(tpr, "nfs server %s: %s\n", server, msg);
2495 	tprintf_close(tpr);
2496 	return (0);
2497 }
2498 
2499 #ifndef NFS_NOSERVER
2500 
2501 /*
2502  * Socket upcall routine for nfsd sockets.  This runs in the protocol
2503  * thread and passes waitflag == MB_DONTWAIT.
2504  */
2505 void
2506 nfsrv_rcv_upcall(struct socket *so, void *arg, int waitflag)
2507 {
2508 	struct nfssvc_sock *slp = (struct nfssvc_sock *)arg;
2509 
2510 	if (slp->ns_needq_upcall == 0) {
2511 		slp->ns_needq_upcall = 1;	/* ok to race */
2512 		lwkt_gettoken(&nfs_token);
2513 		nfsrv_wakenfsd(slp, 1);
2514 		lwkt_reltoken(&nfs_token);
2515 	}
2516 #if 0
2517 	lwkt_gettoken(&slp->ns_token);
2518 	slp->ns_flag |= SLP_NEEDQ;
2519 	nfsrv_rcv(so, arg, waitflag);
2520 	lwkt_reltoken(&slp->ns_token);
2521 #endif
2522 }
2523 
2524 /*
2525  * Process new data on a receive socket.  Essentially do as much as we can
2526  * non-blocking, else punt and it will be called with MB_WAIT from an nfsd.
2527  *
2528  * slp->ns_token is held on call
2529  */
2530 void
2531 nfsrv_rcv(struct socket *so, void *arg, int waitflag)
2532 {
2533 	struct nfssvc_sock *slp = (struct nfssvc_sock *)arg;
2534 	struct mbuf *m;
2535 	struct sockaddr *nam;
2536 	struct sockbuf sio;
2537 	int flags, error;
2538 	int nparallel_wakeup = 0;
2539 
2540 	ASSERT_LWKT_TOKEN_HELD(&slp->ns_token);
2541 
2542 	if ((slp->ns_flag & SLP_VALID) == 0)
2543 		return;
2544 
2545 	/*
2546 	 * Do not allow an infinite number of completed RPC records to build
2547 	 * up before we stop reading data from the socket.  Otherwise we could
2548 	 * end up holding onto an unreasonable number of mbufs for requests
2549 	 * waiting for service.
2550 	 *
2551 	 * This should give pretty good feedback to the TCP layer and
2552 	 * prevents a memory crunch for other protocols.
2553 	 *
2554 	 * Note that the same service socket can be dispatched to several
2555 	 * nfs servers simultaniously.  The tcp protocol callback calls us
2556 	 * with MB_DONTWAIT.  nfsd calls us with MB_WAIT (typically).
2557 	 */
2558 	if (NFSRV_RECLIMIT(slp))
2559 		return;
2560 
2561 	/*
2562 	 * Handle protocol specifics to parse an RPC request.  We always
2563 	 * pull from the socket using non-blocking I/O.
2564 	 */
2565 	if (so->so_type == SOCK_STREAM) {
2566 		/*
2567 		 * The data has to be read in an orderly fashion from a TCP
2568 		 * stream, unlike a UDP socket.  It is possible for soreceive
2569 		 * and/or nfsrv_getstream() to block, so make sure only one
2570 		 * entity is messing around with the TCP stream at any given
2571 		 * moment.  The receive sockbuf's lock in soreceive is not
2572 		 * sufficient.
2573 		 */
2574 		if (slp->ns_flag & SLP_GETSTREAM)
2575 			return;
2576 		slp->ns_flag |= SLP_GETSTREAM;
2577 
2578 		/*
2579 		 * Do soreceive().  Pull out as much data as possible without
2580 		 * blocking.
2581 		 */
2582 		sbinit(&sio, 1000000000);
2583 		flags = MSG_DONTWAIT;
2584 		error = so_pru_soreceive(so, &nam, NULL, &sio, NULL, &flags);
2585 		if (error || sio.sb_mb == NULL) {
2586 			if (error != EWOULDBLOCK)
2587 				slp->ns_flag |= SLP_DISCONN;
2588 			slp->ns_flag &= ~(SLP_GETSTREAM | SLP_NEEDQ);
2589 			goto done;
2590 		}
2591 		m = sio.sb_mb;
2592 		if (slp->ns_rawend) {
2593 			slp->ns_rawend->m_next = m;
2594 			slp->ns_cc += sio.sb_cc;
2595 		} else {
2596 			slp->ns_raw = m;
2597 			slp->ns_cc = sio.sb_cc;
2598 		}
2599 		while (m->m_next)
2600 			m = m->m_next;
2601 		slp->ns_rawend = m;
2602 
2603 		/*
2604 		 * Now try and parse as many record(s) as we can out of the
2605 		 * raw stream data.  This will set SLP_DOREC.
2606 		 */
2607 		error = nfsrv_getstream(slp, waitflag, &nparallel_wakeup);
2608 		if (error && error != EWOULDBLOCK)
2609 			slp->ns_flag |= SLP_DISCONN;
2610 		slp->ns_flag &= ~SLP_GETSTREAM;
2611 	} else {
2612 		/*
2613 		 * For UDP soreceive typically pulls just one packet, loop
2614 		 * to get the whole batch.
2615 		 */
2616 		do {
2617 			sbinit(&sio, 1000000000);
2618 			flags = MSG_DONTWAIT;
2619 			error = so_pru_soreceive(so, &nam, NULL, &sio,
2620 						 NULL, &flags);
2621 			if (sio.sb_mb) {
2622 				struct nfsrv_rec *rec;
2623 				int mf = (waitflag & MB_DONTWAIT) ?
2624 					    M_NOWAIT : M_WAITOK;
2625 				rec = kmalloc(sizeof(struct nfsrv_rec),
2626 					     M_NFSRVDESC, mf);
2627 				if (!rec) {
2628 					if (nam)
2629 						kfree(nam, M_SONAME);
2630 					m_freem(sio.sb_mb);
2631 					continue;
2632 				}
2633 				nfs_realign(&sio.sb_mb, 10 * NFSX_UNSIGNED);
2634 				rec->nr_address = nam;
2635 				rec->nr_packet = sio.sb_mb;
2636 				STAILQ_INSERT_TAIL(&slp->ns_rec, rec, nr_link);
2637 				++slp->ns_numrec;
2638 				slp->ns_flag |= SLP_DOREC;
2639 				++nparallel_wakeup;
2640 			} else {
2641 				slp->ns_flag &= ~SLP_NEEDQ;
2642 			}
2643 			if (error) {
2644 				if ((so->so_proto->pr_flags & PR_CONNREQUIRED)
2645 				    && error != EWOULDBLOCK) {
2646 					slp->ns_flag |= SLP_DISCONN;
2647 					break;
2648 				}
2649 			}
2650 			if (NFSRV_RECLIMIT(slp))
2651 				break;
2652 		} while (sio.sb_mb);
2653 	}
2654 
2655 	/*
2656 	 * If we were upcalled from the tcp protocol layer and we have
2657 	 * fully parsed records ready to go, or there is new data pending,
2658 	 * or something went wrong, try to wake up a nfsd thread to deal
2659 	 * with it.
2660 	 */
2661 done:
2662 	/* XXX this code is currently not executed (nfsrv_rcv_upcall) */
2663 	if (waitflag == MB_DONTWAIT && (slp->ns_flag & SLP_ACTION_MASK)) {
2664 		lwkt_gettoken(&nfs_token);
2665 		nfsrv_wakenfsd(slp, nparallel_wakeup);
2666 		lwkt_reltoken(&nfs_token);
2667 	}
2668 }
2669 
2670 /*
2671  * Try and extract an RPC request from the mbuf data list received on a
2672  * stream socket. The "waitflag" argument indicates whether or not it
2673  * can sleep.
2674  */
2675 static int
2676 nfsrv_getstream(struct nfssvc_sock *slp, int waitflag, int *countp)
2677 {
2678 	struct mbuf *m, **mpp;
2679 	char *cp1, *cp2;
2680 	int len;
2681 	struct mbuf *om, *m2, *recm;
2682 	u_int32_t recmark;
2683 
2684 	for (;;) {
2685 	    if (slp->ns_reclen == 0) {
2686 		if (slp->ns_cc < NFSX_UNSIGNED)
2687 			return (0);
2688 		m = slp->ns_raw;
2689 		if (m->m_len >= NFSX_UNSIGNED) {
2690 			bcopy(mtod(m, caddr_t), (caddr_t)&recmark, NFSX_UNSIGNED);
2691 			m->m_data += NFSX_UNSIGNED;
2692 			m->m_len -= NFSX_UNSIGNED;
2693 		} else {
2694 			cp1 = (caddr_t)&recmark;
2695 			cp2 = mtod(m, caddr_t);
2696 			while (cp1 < ((caddr_t)&recmark) + NFSX_UNSIGNED) {
2697 				while (m->m_len == 0) {
2698 					m = m->m_next;
2699 					cp2 = mtod(m, caddr_t);
2700 				}
2701 				*cp1++ = *cp2++;
2702 				m->m_data++;
2703 				m->m_len--;
2704 			}
2705 		}
2706 		slp->ns_cc -= NFSX_UNSIGNED;
2707 		recmark = ntohl(recmark);
2708 		slp->ns_reclen = recmark & ~0x80000000;
2709 		if (recmark & 0x80000000)
2710 			slp->ns_flag |= SLP_LASTFRAG;
2711 		else
2712 			slp->ns_flag &= ~SLP_LASTFRAG;
2713 		if (slp->ns_reclen > NFS_MAXPACKET || slp->ns_reclen <= 0) {
2714 			log(LOG_ERR, "%s (%d) from nfs client\n",
2715 			    "impossible packet length",
2716 			    slp->ns_reclen);
2717 			return (EPERM);
2718 		}
2719 	    }
2720 
2721 	    /*
2722 	     * Now get the record part.
2723 	     *
2724 	     * Note that slp->ns_reclen may be 0.  Linux sometimes
2725 	     * generates 0-length RPCs
2726 	     */
2727 	    recm = NULL;
2728 	    if (slp->ns_cc == slp->ns_reclen) {
2729 		recm = slp->ns_raw;
2730 		slp->ns_raw = slp->ns_rawend = NULL;
2731 		slp->ns_cc = slp->ns_reclen = 0;
2732 	    } else if (slp->ns_cc > slp->ns_reclen) {
2733 		len = 0;
2734 		m = slp->ns_raw;
2735 		om = NULL;
2736 
2737 		while (len < slp->ns_reclen) {
2738 			if ((len + m->m_len) > slp->ns_reclen) {
2739 				m2 = m_copym(m, 0, slp->ns_reclen - len,
2740 					waitflag);
2741 				if (m2) {
2742 					if (om) {
2743 						om->m_next = m2;
2744 						recm = slp->ns_raw;
2745 					} else
2746 						recm = m2;
2747 					m->m_data += slp->ns_reclen - len;
2748 					m->m_len -= slp->ns_reclen - len;
2749 					len = slp->ns_reclen;
2750 				} else {
2751 					return (EWOULDBLOCK);
2752 				}
2753 			} else if ((len + m->m_len) == slp->ns_reclen) {
2754 				om = m;
2755 				len += m->m_len;
2756 				m = m->m_next;
2757 				recm = slp->ns_raw;
2758 				om->m_next = NULL;
2759 			} else {
2760 				om = m;
2761 				len += m->m_len;
2762 				m = m->m_next;
2763 			}
2764 		}
2765 		slp->ns_raw = m;
2766 		slp->ns_cc -= len;
2767 		slp->ns_reclen = 0;
2768 	    } else {
2769 		return (0);
2770 	    }
2771 
2772 	    /*
2773 	     * Accumulate the fragments into a record.
2774 	     */
2775 	    mpp = &slp->ns_frag;
2776 	    while (*mpp)
2777 		mpp = &((*mpp)->m_next);
2778 	    *mpp = recm;
2779 	    if (slp->ns_flag & SLP_LASTFRAG) {
2780 		struct nfsrv_rec *rec;
2781 		int mf = (waitflag & MB_DONTWAIT) ? M_NOWAIT : M_WAITOK;
2782 		rec = kmalloc(sizeof(struct nfsrv_rec), M_NFSRVDESC, mf);
2783 		if (!rec) {
2784 		    m_freem(slp->ns_frag);
2785 		} else {
2786 		    nfs_realign(&slp->ns_frag, 10 * NFSX_UNSIGNED);
2787 		    rec->nr_address = NULL;
2788 		    rec->nr_packet = slp->ns_frag;
2789 		    STAILQ_INSERT_TAIL(&slp->ns_rec, rec, nr_link);
2790 		    ++slp->ns_numrec;
2791 		    slp->ns_flag |= SLP_DOREC;
2792 		    ++*countp;
2793 		}
2794 		slp->ns_frag = NULL;
2795 	    }
2796 	}
2797 }
2798 
2799 #ifdef INVARIANTS
2800 
2801 /*
2802  * Sanity check our mbuf chain.
2803  */
2804 static void
2805 nfs_checkpkt(struct mbuf *m, int len)
2806 {
2807 	int xlen = 0;
2808 	while (m) {
2809 		xlen += m->m_len;
2810 		m = m->m_next;
2811 	}
2812 	if (xlen != len) {
2813 		panic("nfs_checkpkt: len mismatch %d/%d mbuf %p",
2814 			xlen, len, m);
2815 	}
2816 }
2817 
2818 #else
2819 
2820 static void
2821 nfs_checkpkt(struct mbuf *m __unused, int len __unused)
2822 {
2823 }
2824 
2825 #endif
2826 
2827 /*
2828  * Parse an RPC header.
2829  *
2830  * If the socket is invalid or no records are pending we return ENOBUFS.
2831  * The caller must deal with NEEDQ races.
2832  */
2833 int
2834 nfsrv_dorec(struct nfssvc_sock *slp, struct nfsd *nfsd,
2835 	    struct nfsrv_descript **ndp)
2836 {
2837 	struct nfsrv_rec *rec;
2838 	struct mbuf *m;
2839 	struct sockaddr *nam;
2840 	struct nfsrv_descript *nd;
2841 	int error;
2842 
2843 	*ndp = NULL;
2844 	if ((slp->ns_flag & SLP_VALID) == 0 || !STAILQ_FIRST(&slp->ns_rec))
2845 		return (ENOBUFS);
2846 	rec = STAILQ_FIRST(&slp->ns_rec);
2847 	STAILQ_REMOVE_HEAD(&slp->ns_rec, nr_link);
2848 	KKASSERT(slp->ns_numrec > 0);
2849 	if (--slp->ns_numrec == 0)
2850 		slp->ns_flag &= ~SLP_DOREC;
2851 	nam = rec->nr_address;
2852 	m = rec->nr_packet;
2853 	kfree(rec, M_NFSRVDESC);
2854 	nd = kmalloc(sizeof(struct nfsrv_descript), M_NFSRVDESC, M_WAITOK);
2855 	nd->nd_md = nd->nd_mrep = m;
2856 	nd->nd_nam2 = nam;
2857 	nd->nd_dpos = mtod(m, caddr_t);
2858 	error = nfs_getreq(nd, nfsd, TRUE);
2859 	if (error) {
2860 		if (nam) {
2861 			kfree(nam, M_SONAME);
2862 		}
2863 		kfree((caddr_t)nd, M_NFSRVDESC);
2864 		return (error);
2865 	}
2866 	*ndp = nd;
2867 	nfsd->nfsd_nd = nd;
2868 	return (0);
2869 }
2870 
2871 /*
2872  * Try to assign service sockets to nfsd threads based on the number
2873  * of new rpc requests that have been queued on the service socket.
2874  *
2875  * If no nfsd's are available or additonal requests are pending, set the
2876  * NFSD_CHECKSLP flag so that one of the running nfsds will go look for
2877  * the work in the nfssvc_sock list when it is finished processing its
2878  * current work.  This flag is only cleared when an nfsd can not find
2879  * any new work to perform.
2880  */
2881 void
2882 nfsrv_wakenfsd(struct nfssvc_sock *slp, int nparallel)
2883 {
2884 	struct nfsd *nd;
2885 
2886 	if ((slp->ns_flag & SLP_VALID) == 0)
2887 		return;
2888 	if (nparallel <= 1)
2889 		nparallel = 1;
2890 	TAILQ_FOREACH(nd, &nfsd_head, nfsd_chain) {
2891 		if (nd->nfsd_flag & NFSD_WAITING) {
2892 			nd->nfsd_flag &= ~NFSD_WAITING;
2893 			if (nd->nfsd_slp)
2894 				panic("nfsd wakeup");
2895 			nfsrv_slpref(slp);
2896 			nd->nfsd_slp = slp;
2897 			wakeup((caddr_t)nd);
2898 			if (--nparallel == 0)
2899 				break;
2900 		}
2901 	}
2902 
2903 	/*
2904 	 * If we couldn't assign slp then the NFSDs are all busy and
2905 	 * we set a flag indicating that there is pending work.
2906 	 */
2907 	if (nparallel)
2908 		nfsd_head_flag |= NFSD_CHECKSLP;
2909 }
2910 #endif /* NFS_NOSERVER */
2911