xref: /netbsd-src/sys/nfs/nfs_socket.c (revision cac8e449158efc7261bebc8657cbb0125a2cfdde)
1 /*	$NetBSD: nfs_socket.c,v 1.170 2008/04/24 11:38:39 ad Exp $	*/
2 
3 /*
4  * Copyright (c) 1989, 1991, 1993, 1995
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * This code is derived from software contributed to Berkeley by
8  * Rick Macklem at The University of Guelph.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. Neither the name of the University nor the names of its contributors
19  *    may be used to endorse or promote products derived from this software
20  *    without specific prior written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  *
34  *	@(#)nfs_socket.c	8.5 (Berkeley) 3/30/95
35  */
36 
37 /*
38  * Socket operations for use by nfs
39  */
40 
41 #include <sys/cdefs.h>
42 __KERNEL_RCSID(0, "$NetBSD: nfs_socket.c,v 1.170 2008/04/24 11:38:39 ad Exp $");
43 
44 #include "fs_nfs.h"
45 #include "opt_nfs.h"
46 #include "opt_nfsserver.h"
47 #include "opt_mbuftrace.h"
48 #include "opt_inet.h"
49 
50 #include <sys/param.h>
51 #include <sys/systm.h>
52 #include <sys/evcnt.h>
53 #include <sys/callout.h>
54 #include <sys/proc.h>
55 #include <sys/mount.h>
56 #include <sys/kernel.h>
57 #include <sys/kmem.h>
58 #include <sys/mbuf.h>
59 #include <sys/vnode.h>
60 #include <sys/domain.h>
61 #include <sys/protosw.h>
62 #include <sys/socket.h>
63 #include <sys/socketvar.h>
64 #include <sys/syslog.h>
65 #include <sys/tprintf.h>
66 #include <sys/namei.h>
67 #include <sys/signal.h>
68 #include <sys/signalvar.h>
69 #include <sys/kauth.h>
70 
71 #include <netinet/in.h>
72 #include <netinet/tcp.h>
73 
74 #include <nfs/rpcv2.h>
75 #include <nfs/nfsproto.h>
76 #include <nfs/nfs.h>
77 #include <nfs/xdr_subs.h>
78 #include <nfs/nfsm_subs.h>
79 #include <nfs/nfsmount.h>
80 #include <nfs/nfsnode.h>
81 #include <nfs/nfsrtt.h>
82 #include <nfs/nfs_var.h>
83 
84 #ifdef MBUFTRACE
85 struct mowner nfs_mowner = MOWNER_INIT("nfs","");
86 #endif
87 
88 /*
89  * Estimate rto for an nfs rpc sent via. an unreliable datagram.
90  * Use the mean and mean deviation of rtt for the appropriate type of rpc
91  * for the frequent rpcs and a default for the others.
92  * The justification for doing "other" this way is that these rpcs
93  * happen so infrequently that timer est. would probably be stale.
94  * Also, since many of these rpcs are
95  * non-idempotent, a conservative timeout is desired.
96  * getattr, lookup - A+2D
97  * read, write     - A+4D
98  * other           - nm_timeo
99  */
100 #define	NFS_RTO(n, t) \
101 	((t) == 0 ? (n)->nm_timeo : \
102 	 ((t) < 3 ? \
103 	  (((((n)->nm_srtt[t-1] + 3) >> 2) + (n)->nm_sdrtt[t-1] + 1) >> 1) : \
104 	  ((((n)->nm_srtt[t-1] + 7) >> 3) + (n)->nm_sdrtt[t-1] + 1)))
105 #define	NFS_SRTT(r)	(r)->r_nmp->nm_srtt[proct[(r)->r_procnum] - 1]
106 #define	NFS_SDRTT(r)	(r)->r_nmp->nm_sdrtt[proct[(r)->r_procnum] - 1]
107 /*
108  * External data, mostly RPC constants in XDR form
109  */
110 extern u_int32_t rpc_reply, rpc_msgdenied, rpc_mismatch, rpc_vers,
111 	rpc_auth_unix, rpc_msgaccepted, rpc_call, rpc_autherr,
112 	rpc_auth_kerb;
113 extern u_int32_t nfs_prog;
114 extern const int nfsv3_procid[NFS_NPROCS];
115 extern int nfs_ticks;
116 
117 /*
118  * Defines which timer to use for the procnum.
119  * 0 - default
120  * 1 - getattr
121  * 2 - lookup
122  * 3 - read
123  * 4 - write
124  */
125 static const int proct[NFS_NPROCS] = {
126 	[NFSPROC_NULL] = 0,
127 	[NFSPROC_GETATTR] = 1,
128 	[NFSPROC_SETATTR] = 0,
129 	[NFSPROC_LOOKUP] = 2,
130 	[NFSPROC_ACCESS] = 1,
131 	[NFSPROC_READLINK] = 3,
132 	[NFSPROC_READ] = 3,
133 	[NFSPROC_WRITE] = 4,
134 	[NFSPROC_CREATE] = 0,
135 	[NFSPROC_MKDIR] = 0,
136 	[NFSPROC_SYMLINK] = 0,
137 	[NFSPROC_MKNOD] = 0,
138 	[NFSPROC_REMOVE] = 0,
139 	[NFSPROC_RMDIR] = 0,
140 	[NFSPROC_RENAME] = 0,
141 	[NFSPROC_LINK] = 0,
142 	[NFSPROC_READDIR] = 3,
143 	[NFSPROC_READDIRPLUS] = 3,
144 	[NFSPROC_FSSTAT] = 0,
145 	[NFSPROC_FSINFO] = 0,
146 	[NFSPROC_PATHCONF] = 0,
147 	[NFSPROC_COMMIT] = 0,
148 	[NFSPROC_NOOP] = 0,
149 };
150 
151 /*
152  * There is a congestion window for outstanding rpcs maintained per mount
153  * point. The cwnd size is adjusted in roughly the way that:
154  * Van Jacobson, Congestion avoidance and Control, In "Proceedings of
155  * SIGCOMM '88". ACM, August 1988.
156  * describes for TCP. The cwnd size is chopped in half on a retransmit timeout
157  * and incremented by 1/cwnd when each rpc reply is received and a full cwnd
158  * of rpcs is in progress.
159  * (The sent count and cwnd are scaled for integer arith.)
160  * Variants of "slow start" were tried and were found to be too much of a
161  * performance hit (ave. rtt 3 times larger),
162  * I suspect due to the large rtt that nfs rpcs have.
163  */
164 #define	NFS_CWNDSCALE	256
165 #define	NFS_MAXCWND	(NFS_CWNDSCALE * 32)
166 static const int nfs_backoff[8] = { 2, 4, 8, 16, 32, 64, 128, 256, };
167 int nfsrtton = 0;
168 struct nfsrtt nfsrtt;
169 struct nfsreqhead nfs_reqq;
170 static callout_t nfs_timer_ch;
171 static struct evcnt nfs_timer_ev;
172 static struct evcnt nfs_timer_start_ev;
173 static struct evcnt nfs_timer_stop_ev;
174 
175 static int nfs_sndlock(struct nfsmount *, struct nfsreq *);
176 static void nfs_sndunlock(struct nfsmount *);
177 static int nfs_rcvlock(struct nfsmount *, struct nfsreq *);
178 static void nfs_rcvunlock(struct nfsmount *);
179 
180 #if defined(NFSSERVER)
181 static void nfsrv_wakenfsd_locked(struct nfssvc_sock *);
182 #endif /* defined(NFSSERVER) */
183 
184 /*
185  * Initialize sockets and congestion for a new NFS connection.
186  * We do not free the sockaddr if error.
187  */
188 int
189 nfs_connect(nmp, rep, l)
190 	struct nfsmount *nmp;
191 	struct nfsreq *rep;
192 	struct lwp *l;
193 {
194 	struct socket *so;
195 	int error, rcvreserve, sndreserve;
196 	struct sockaddr *saddr;
197 	struct sockaddr_in *sin;
198 #ifdef INET6
199 	struct sockaddr_in6 *sin6;
200 #endif
201 	struct mbuf *m;
202 
203 	nmp->nm_so = (struct socket *)0;
204 	saddr = mtod(nmp->nm_nam, struct sockaddr *);
205 	error = socreate(saddr->sa_family, &nmp->nm_so,
206 		nmp->nm_sotype, nmp->nm_soproto, l, NULL);
207 	if (error)
208 		goto bad;
209 	so = nmp->nm_so;
210 #ifdef MBUFTRACE
211 	so->so_mowner = &nfs_mowner;
212 	so->so_rcv.sb_mowner = &nfs_mowner;
213 	so->so_snd.sb_mowner = &nfs_mowner;
214 #endif
215 	nmp->nm_soflags = so->so_proto->pr_flags;
216 
217 	/*
218 	 * Some servers require that the client port be a reserved port number.
219 	 */
220 	if (saddr->sa_family == AF_INET && (nmp->nm_flag & NFSMNT_RESVPORT)) {
221 		m = m_get(M_WAIT, MT_SOOPTS);
222 		MCLAIM(m, so->so_mowner);
223 		*mtod(m, int32_t *) = IP_PORTRANGE_LOW;
224 		m->m_len = sizeof(int32_t);
225 		if ((error = sosetopt(so, IPPROTO_IP, IP_PORTRANGE, m)))
226 			goto bad;
227 		m = m_get(M_WAIT, MT_SONAME);
228 		MCLAIM(m, so->so_mowner);
229 		sin = mtod(m, struct sockaddr_in *);
230 		sin->sin_len = m->m_len = sizeof (struct sockaddr_in);
231 		sin->sin_family = AF_INET;
232 		sin->sin_addr.s_addr = INADDR_ANY;
233 		sin->sin_port = 0;
234 		error = sobind(so, m, &lwp0);
235 		m_freem(m);
236 		if (error)
237 			goto bad;
238 	}
239 #ifdef INET6
240 	if (saddr->sa_family == AF_INET6 && (nmp->nm_flag & NFSMNT_RESVPORT)) {
241 		m = m_get(M_WAIT, MT_SOOPTS);
242 		MCLAIM(m, so->so_mowner);
243 		*mtod(m, int32_t *) = IPV6_PORTRANGE_LOW;
244 		m->m_len = sizeof(int32_t);
245 		if ((error = sosetopt(so, IPPROTO_IPV6, IPV6_PORTRANGE, m)))
246 			goto bad;
247 		m = m_get(M_WAIT, MT_SONAME);
248 		MCLAIM(m, so->so_mowner);
249 		sin6 = mtod(m, struct sockaddr_in6 *);
250 		sin6->sin6_len = m->m_len = sizeof (struct sockaddr_in6);
251 		sin6->sin6_family = AF_INET6;
252 		sin6->sin6_addr = in6addr_any;
253 		sin6->sin6_port = 0;
254 		error = sobind(so, m, &lwp0);
255 		m_freem(m);
256 		if (error)
257 			goto bad;
258 	}
259 #endif
260 
261 	/*
262 	 * Protocols that do not require connections may be optionally left
263 	 * unconnected for servers that reply from a port other than NFS_PORT.
264 	 */
265 	solock(so);
266 	if (nmp->nm_flag & NFSMNT_NOCONN) {
267 		if (nmp->nm_soflags & PR_CONNREQUIRED) {
268 			sounlock(so);
269 			error = ENOTCONN;
270 			goto bad;
271 		}
272 	} else {
273 		error = soconnect(so, nmp->nm_nam, l);
274 		if (error) {
275 			sounlock(so);
276 			goto bad;
277 		}
278 
279 		/*
280 		 * Wait for the connection to complete. Cribbed from the
281 		 * connect system call but with the wait timing out so
282 		 * that interruptible mounts don't hang here for a long time.
283 		 */
284 		while ((so->so_state & SS_ISCONNECTING) && so->so_error == 0) {
285 			(void)sowait(so, 2 * hz);
286 			if ((so->so_state & SS_ISCONNECTING) &&
287 			    so->so_error == 0 && rep &&
288 			    (error = nfs_sigintr(nmp, rep, rep->r_lwp)) != 0){
289 				so->so_state &= ~SS_ISCONNECTING;
290 				sounlock(so);
291 				goto bad;
292 			}
293 		}
294 		if (so->so_error) {
295 			error = so->so_error;
296 			so->so_error = 0;
297 			sounlock(so);
298 			goto bad;
299 		}
300 	}
301 	if (nmp->nm_flag & (NFSMNT_SOFT | NFSMNT_INT)) {
302 		so->so_rcv.sb_timeo = (5 * hz);
303 		so->so_snd.sb_timeo = (5 * hz);
304 	} else {
305 		/*
306 		 * enable receive timeout to detect server crash and reconnect.
307 		 * otherwise, we can be stuck in soreceive forever.
308 		 */
309 		so->so_rcv.sb_timeo = (5 * hz);
310 		so->so_snd.sb_timeo = 0;
311 	}
312 	if (nmp->nm_sotype == SOCK_DGRAM) {
313 		sndreserve = (nmp->nm_wsize + NFS_MAXPKTHDR) * 2;
314 		rcvreserve = (max(nmp->nm_rsize, nmp->nm_readdirsize) +
315 		    NFS_MAXPKTHDR) * 2;
316 	} else if (nmp->nm_sotype == SOCK_SEQPACKET) {
317 		sndreserve = (nmp->nm_wsize + NFS_MAXPKTHDR) * 2;
318 		rcvreserve = (max(nmp->nm_rsize, nmp->nm_readdirsize) +
319 		    NFS_MAXPKTHDR) * 2;
320 	} else {
321 		sounlock(so);
322 		if (nmp->nm_sotype != SOCK_STREAM)
323 			panic("nfscon sotype");
324 		if (so->so_proto->pr_flags & PR_CONNREQUIRED) {
325 			m = m_get(M_WAIT, MT_SOOPTS);
326 			MCLAIM(m, so->so_mowner);
327 			*mtod(m, int32_t *) = 1;
328 			m->m_len = sizeof(int32_t);
329 			sosetopt(so, SOL_SOCKET, SO_KEEPALIVE, m);
330 		}
331 		if (so->so_proto->pr_protocol == IPPROTO_TCP) {
332 			m = m_get(M_WAIT, MT_SOOPTS);
333 			MCLAIM(m, so->so_mowner);
334 			*mtod(m, int32_t *) = 1;
335 			m->m_len = sizeof(int32_t);
336 			sosetopt(so, IPPROTO_TCP, TCP_NODELAY, m);
337 		}
338 		sndreserve = (nmp->nm_wsize + NFS_MAXPKTHDR +
339 		    sizeof (u_int32_t)) * 2;
340 		rcvreserve = (nmp->nm_rsize + NFS_MAXPKTHDR +
341 		    sizeof (u_int32_t)) * 2;
342 		solock(so);
343 	}
344 	error = soreserve(so, sndreserve, rcvreserve);
345 	if (error) {
346 		sounlock(so);
347 		goto bad;
348 	}
349 	so->so_rcv.sb_flags |= SB_NOINTR;
350 	so->so_snd.sb_flags |= SB_NOINTR;
351 	sounlock(so);
352 
353 	/* Initialize other non-zero congestion variables */
354 	nmp->nm_srtt[0] = nmp->nm_srtt[1] = nmp->nm_srtt[2] = nmp->nm_srtt[3] =
355 		NFS_TIMEO << 3;
356 	nmp->nm_sdrtt[0] = nmp->nm_sdrtt[1] = nmp->nm_sdrtt[2] =
357 		nmp->nm_sdrtt[3] = 0;
358 	nmp->nm_cwnd = NFS_MAXCWND / 2;	    /* Initial send window */
359 	nmp->nm_sent = 0;
360 	nmp->nm_timeouts = 0;
361 	return (0);
362 
363 bad:
364 	nfs_disconnect(nmp);
365 	return (error);
366 }
367 
368 /*
369  * Reconnect routine:
370  * Called when a connection is broken on a reliable protocol.
371  * - clean up the old socket
372  * - nfs_connect() again
373  * - set R_MUSTRESEND for all outstanding requests on mount point
374  * If this fails the mount point is DEAD!
375  * nb: Must be called with the nfs_sndlock() set on the mount point.
376  */
377 int
378 nfs_reconnect(struct nfsreq *rep)
379 {
380 	struct nfsreq *rp;
381 	struct nfsmount *nmp = rep->r_nmp;
382 	int error;
383 
384 	nfs_disconnect(nmp);
385 	while ((error = nfs_connect(nmp, rep, &lwp0)) != 0) {
386 		if (error == EINTR || error == ERESTART)
387 			return (EINTR);
388 		kpause("nfscn2", false, hz, NULL);
389 	}
390 
391 	/*
392 	 * Loop through outstanding request list and fix up all requests
393 	 * on old socket.
394 	 */
395 	TAILQ_FOREACH(rp, &nfs_reqq, r_chain) {
396 		if (rp->r_nmp == nmp) {
397 			if ((rp->r_flags & R_MUSTRESEND) == 0)
398 				rp->r_flags |= R_MUSTRESEND | R_REXMITTED;
399 			rp->r_rexmit = 0;
400 		}
401 	}
402 	return (0);
403 }
404 
405 /*
406  * NFS disconnect. Clean up and unlink.
407  */
408 void
409 nfs_disconnect(nmp)
410 	struct nfsmount *nmp;
411 {
412 	struct socket *so;
413 	int drain = 0;
414 
415 	if (nmp->nm_so) {
416 		so = nmp->nm_so;
417 		nmp->nm_so = (struct socket *)0;
418 		solock(so);
419 		soshutdown(so, SHUT_RDWR);
420 		sounlock(so);
421 		drain = (nmp->nm_iflag & NFSMNT_DISMNT) != 0;
422 		if (drain) {
423 			/*
424 			 * soshutdown() above should wake up the current
425 			 * listener.
426 			 * Now wake up those waiting for the receive lock, and
427 			 * wait for them to go away unhappy, to prevent *nmp
428 			 * from evaporating while they're sleeping.
429 			 */
430 			mutex_enter(&nmp->nm_lock);
431 			while (nmp->nm_waiters > 0) {
432 				cv_broadcast(&nmp->nm_rcvcv);
433 				cv_broadcast(&nmp->nm_sndcv);
434 				cv_wait(&nmp->nm_disconcv, &nmp->nm_lock);
435 			}
436 			mutex_exit(&nmp->nm_lock);
437 		}
438 		soclose(so);
439 	}
440 #ifdef DIAGNOSTIC
441 	if (drain && (nmp->nm_waiters > 0))
442 		panic("nfs_disconnect: waiters left after drain?");
443 #endif
444 }
445 
446 void
447 nfs_safedisconnect(nmp)
448 	struct nfsmount *nmp;
449 {
450 	struct nfsreq dummyreq;
451 
452 	memset(&dummyreq, 0, sizeof(dummyreq));
453 	dummyreq.r_nmp = nmp;
454 	nfs_rcvlock(nmp, &dummyreq); /* XXX ignored error return */
455 	nfs_disconnect(nmp);
456 	nfs_rcvunlock(nmp);
457 }
458 
459 /*
460  * This is the nfs send routine. For connection based socket types, it
461  * must be called with an nfs_sndlock() on the socket.
462  * "rep == NULL" indicates that it has been called from a server.
463  * For the client side:
464  * - return EINTR if the RPC is terminated, 0 otherwise
465  * - set R_MUSTRESEND if the send fails for any reason
466  * - do any cleanup required by recoverable socket errors (? ? ?)
467  * For the server side:
468  * - return EINTR or ERESTART if interrupted by a signal
469  * - return EPIPE if a connection is lost for connection based sockets (TCP...)
470  * - do any cleanup required by recoverable socket errors (? ? ?)
471  */
472 int
473 nfs_send(so, nam, top, rep, l)
474 	struct socket *so;
475 	struct mbuf *nam;
476 	struct mbuf *top;
477 	struct nfsreq *rep;
478 	struct lwp *l;
479 {
480 	struct mbuf *sendnam;
481 	int error, soflags, flags;
482 
483 	/* XXX nfs_doio()/nfs_request() calls with  rep->r_lwp == NULL */
484 	if (l == NULL && rep->r_lwp == NULL)
485 		l = curlwp;
486 
487 	if (rep) {
488 		if (rep->r_flags & R_SOFTTERM) {
489 			m_freem(top);
490 			return (EINTR);
491 		}
492 		if ((so = rep->r_nmp->nm_so) == NULL) {
493 			rep->r_flags |= R_MUSTRESEND;
494 			m_freem(top);
495 			return (0);
496 		}
497 		rep->r_flags &= ~R_MUSTRESEND;
498 		soflags = rep->r_nmp->nm_soflags;
499 	} else
500 		soflags = so->so_proto->pr_flags;
501 	if ((soflags & PR_CONNREQUIRED) || (so->so_state & SS_ISCONNECTED))
502 		sendnam = (struct mbuf *)0;
503 	else
504 		sendnam = nam;
505 	if (so->so_type == SOCK_SEQPACKET)
506 		flags = MSG_EOR;
507 	else
508 		flags = 0;
509 
510 	error = (*so->so_send)(so, sendnam, NULL, top, NULL, flags,  l);
511 	if (error) {
512 		if (rep) {
513 			if (error == ENOBUFS && so->so_type == SOCK_DGRAM) {
514 				/*
515 				 * We're too fast for the network/driver,
516 				 * and UDP isn't flowcontrolled.
517 				 * We need to resend. This is not fatal,
518 				 * just try again.
519 				 *
520 				 * Could be smarter here by doing some sort
521 				 * of a backoff, but this is rare.
522 				 */
523 				rep->r_flags |= R_MUSTRESEND;
524 			} else {
525 				if (error != EPIPE)
526 					log(LOG_INFO,
527 					    "nfs send error %d for %s\n",
528 					    error,
529 					    rep->r_nmp->nm_mountp->
530 						    mnt_stat.f_mntfromname);
531 				/*
532 				 * Deal with errors for the client side.
533 				 */
534 				if (rep->r_flags & R_SOFTTERM)
535 					error = EINTR;
536 				else
537 					rep->r_flags |= R_MUSTRESEND;
538 			}
539 		} else {
540 			/*
541 			 * See above. This error can happen under normal
542 			 * circumstances and the log is too noisy.
543 			 * The error will still show up in nfsstat.
544 			 */
545 			if (error != ENOBUFS || so->so_type != SOCK_DGRAM)
546 				log(LOG_INFO, "nfsd send error %d\n", error);
547 		}
548 
549 		/*
550 		 * Handle any recoverable (soft) socket errors here. (? ? ?)
551 		 */
552 		if (error != EINTR && error != ERESTART &&
553 			error != EWOULDBLOCK && error != EPIPE)
554 			error = 0;
555 	}
556 	return (error);
557 }
558 
559 #ifdef NFS
560 /*
561  * Receive a Sun RPC Request/Reply. For SOCK_DGRAM, the work is all
562  * done by soreceive(), but for SOCK_STREAM we must deal with the Record
563  * Mark and consolidate the data into a new mbuf list.
564  * nb: Sometimes TCP passes the data up to soreceive() in long lists of
565  *     small mbufs.
566  * For SOCK_STREAM we must be very careful to read an entire record once
567  * we have read any of it, even if the system call has been interrupted.
568  */
569 static int
570 nfs_receive(struct nfsreq *rep, struct mbuf **aname, struct mbuf **mp,
571     struct lwp *l)
572 {
573 	struct socket *so;
574 	struct uio auio;
575 	struct iovec aio;
576 	struct mbuf *m;
577 	struct mbuf *control;
578 	u_int32_t len;
579 	struct mbuf **getnam;
580 	int error, sotype, rcvflg;
581 
582 	/*
583 	 * Set up arguments for soreceive()
584 	 */
585 	*mp = (struct mbuf *)0;
586 	*aname = (struct mbuf *)0;
587 	sotype = rep->r_nmp->nm_sotype;
588 
589 	/*
590 	 * For reliable protocols, lock against other senders/receivers
591 	 * in case a reconnect is necessary.
592 	 * For SOCK_STREAM, first get the Record Mark to find out how much
593 	 * more there is to get.
594 	 * We must lock the socket against other receivers
595 	 * until we have an entire rpc request/reply.
596 	 */
597 	if (sotype != SOCK_DGRAM) {
598 		error = nfs_sndlock(rep->r_nmp, rep);
599 		if (error)
600 			return (error);
601 tryagain:
602 		/*
603 		 * Check for fatal errors and resending request.
604 		 */
605 		/*
606 		 * Ugh: If a reconnect attempt just happened, nm_so
607 		 * would have changed. NULL indicates a failed
608 		 * attempt that has essentially shut down this
609 		 * mount point.
610 		 */
611 		if (rep->r_mrep || (rep->r_flags & R_SOFTTERM)) {
612 			nfs_sndunlock(rep->r_nmp);
613 			return (EINTR);
614 		}
615 		so = rep->r_nmp->nm_so;
616 		if (!so) {
617 			error = nfs_reconnect(rep);
618 			if (error) {
619 				nfs_sndunlock(rep->r_nmp);
620 				return (error);
621 			}
622 			goto tryagain;
623 		}
624 		while (rep->r_flags & R_MUSTRESEND) {
625 			m = m_copym(rep->r_mreq, 0, M_COPYALL, M_WAIT);
626 			nfsstats.rpcretries++;
627 			rep->r_rtt = 0;
628 			rep->r_flags &= ~R_TIMING;
629 			error = nfs_send(so, rep->r_nmp->nm_nam, m, rep, l);
630 			if (error) {
631 				if (error == EINTR || error == ERESTART ||
632 				    (error = nfs_reconnect(rep)) != 0) {
633 					nfs_sndunlock(rep->r_nmp);
634 					return (error);
635 				}
636 				goto tryagain;
637 			}
638 		}
639 		nfs_sndunlock(rep->r_nmp);
640 		if (sotype == SOCK_STREAM) {
641 			aio.iov_base = (void *) &len;
642 			aio.iov_len = sizeof(u_int32_t);
643 			auio.uio_iov = &aio;
644 			auio.uio_iovcnt = 1;
645 			auio.uio_rw = UIO_READ;
646 			auio.uio_offset = 0;
647 			auio.uio_resid = sizeof(u_int32_t);
648 			UIO_SETUP_SYSSPACE(&auio);
649 			do {
650 			   rcvflg = MSG_WAITALL;
651 			   error = (*so->so_receive)(so, (struct mbuf **)0, &auio,
652 				(struct mbuf **)0, (struct mbuf **)0, &rcvflg);
653 			   if (error == EWOULDBLOCK && rep) {
654 				if (rep->r_flags & R_SOFTTERM)
655 					return (EINTR);
656 				/*
657 				 * if it seems that the server died after it
658 				 * received our request, set EPIPE so that
659 				 * we'll reconnect and retransmit requests.
660 				 */
661 				if (rep->r_rexmit >= rep->r_nmp->nm_retry) {
662 					nfsstats.rpctimeouts++;
663 					error = EPIPE;
664 				}
665 			   }
666 			} while (error == EWOULDBLOCK);
667 			if (!error && auio.uio_resid > 0) {
668 			    /*
669 			     * Don't log a 0 byte receive; it means
670 			     * that the socket has been closed, and
671 			     * can happen during normal operation
672 			     * (forcible unmount or Solaris server).
673 			     */
674 			    if (auio.uio_resid != sizeof (u_int32_t))
675 			      log(LOG_INFO,
676 				 "short receive (%lu/%lu) from nfs server %s\n",
677 				 (u_long)sizeof(u_int32_t) - auio.uio_resid,
678 				 (u_long)sizeof(u_int32_t),
679 				 rep->r_nmp->nm_mountp->mnt_stat.f_mntfromname);
680 			    error = EPIPE;
681 			}
682 			if (error)
683 				goto errout;
684 			len = ntohl(len) & ~0x80000000;
685 			/*
686 			 * This is SERIOUS! We are out of sync with the sender
687 			 * and forcing a disconnect/reconnect is all I can do.
688 			 */
689 			if (len > NFS_MAXPACKET) {
690 			    log(LOG_ERR, "%s (%d) from nfs server %s\n",
691 				"impossible packet length",
692 				len,
693 				rep->r_nmp->nm_mountp->mnt_stat.f_mntfromname);
694 			    error = EFBIG;
695 			    goto errout;
696 			}
697 			auio.uio_resid = len;
698 			do {
699 			    rcvflg = MSG_WAITALL;
700 			    error =  (*so->so_receive)(so, (struct mbuf **)0,
701 				&auio, mp, (struct mbuf **)0, &rcvflg);
702 			} while (error == EWOULDBLOCK || error == EINTR ||
703 				 error == ERESTART);
704 			if (!error && auio.uio_resid > 0) {
705 			    if (len != auio.uio_resid)
706 			      log(LOG_INFO,
707 				"short receive (%lu/%d) from nfs server %s\n",
708 				(u_long)len - auio.uio_resid, len,
709 				rep->r_nmp->nm_mountp->mnt_stat.f_mntfromname);
710 			    error = EPIPE;
711 			}
712 		} else {
713 			/*
714 			 * NB: Since uio_resid is big, MSG_WAITALL is ignored
715 			 * and soreceive() will return when it has either a
716 			 * control msg or a data msg.
717 			 * We have no use for control msg., but must grab them
718 			 * and then throw them away so we know what is going
719 			 * on.
720 			 */
721 			auio.uio_resid = len = 100000000; /* Anything Big */
722 			/* not need to setup uio_vmspace */
723 			do {
724 			    rcvflg = 0;
725 			    error =  (*so->so_receive)(so, (struct mbuf **)0,
726 				&auio, mp, &control, &rcvflg);
727 			    if (control)
728 				m_freem(control);
729 			    if (error == EWOULDBLOCK && rep) {
730 				if (rep->r_flags & R_SOFTTERM)
731 					return (EINTR);
732 			    }
733 			} while (error == EWOULDBLOCK ||
734 				 (!error && *mp == NULL && control));
735 			if ((rcvflg & MSG_EOR) == 0)
736 				printf("Egad!!\n");
737 			if (!error && *mp == NULL)
738 				error = EPIPE;
739 			len -= auio.uio_resid;
740 		}
741 errout:
742 		if (error && error != EINTR && error != ERESTART) {
743 			m_freem(*mp);
744 			*mp = (struct mbuf *)0;
745 			if (error != EPIPE)
746 				log(LOG_INFO,
747 				    "receive error %d from nfs server %s\n",
748 				    error,
749 				 rep->r_nmp->nm_mountp->mnt_stat.f_mntfromname);
750 			error = nfs_sndlock(rep->r_nmp, rep);
751 			if (!error)
752 				error = nfs_reconnect(rep);
753 			if (!error)
754 				goto tryagain;
755 			else
756 				nfs_sndunlock(rep->r_nmp);
757 		}
758 	} else {
759 		if ((so = rep->r_nmp->nm_so) == NULL)
760 			return (EACCES);
761 		if (so->so_state & SS_ISCONNECTED)
762 			getnam = (struct mbuf **)0;
763 		else
764 			getnam = aname;
765 		auio.uio_resid = len = 1000000;
766 		/* not need to setup uio_vmspace */
767 		do {
768 			rcvflg = 0;
769 			error =  (*so->so_receive)(so, getnam, &auio, mp,
770 				(struct mbuf **)0, &rcvflg);
771 			if (error == EWOULDBLOCK &&
772 			    (rep->r_flags & R_SOFTTERM))
773 				return (EINTR);
774 		} while (error == EWOULDBLOCK);
775 		len -= auio.uio_resid;
776 		if (!error && *mp == NULL)
777 			error = EPIPE;
778 	}
779 	if (error) {
780 		m_freem(*mp);
781 		*mp = (struct mbuf *)0;
782 	}
783 	return (error);
784 }
785 
786 /*
787  * Implement receipt of reply on a socket.
788  * We must search through the list of received datagrams matching them
789  * with outstanding requests using the xid, until ours is found.
790  */
791 /* ARGSUSED */
792 static int
793 nfs_reply(struct nfsreq *myrep, struct lwp *lwp)
794 {
795 	struct nfsreq *rep;
796 	struct nfsmount *nmp = myrep->r_nmp;
797 	int32_t t1;
798 	struct mbuf *mrep, *nam, *md;
799 	u_int32_t rxid, *tl;
800 	char *dpos, *cp2;
801 	int error;
802 
803 	/*
804 	 * Loop around until we get our own reply
805 	 */
806 	for (;;) {
807 		/*
808 		 * Lock against other receivers so that I don't get stuck in
809 		 * sbwait() after someone else has received my reply for me.
810 		 * Also necessary for connection based protocols to avoid
811 		 * race conditions during a reconnect.
812 		 */
813 		error = nfs_rcvlock(nmp, myrep);
814 		if (error == EALREADY)
815 			return (0);
816 		if (error)
817 			return (error);
818 		/*
819 		 * Get the next Rpc reply off the socket
820 		 */
821 
822 		mutex_enter(&nmp->nm_lock);
823 		nmp->nm_waiters++;
824 		mutex_exit(&nmp->nm_lock);
825 
826 		error = nfs_receive(myrep, &nam, &mrep, lwp);
827 
828 		mutex_enter(&nmp->nm_lock);
829 		nmp->nm_waiters--;
830 		cv_signal(&nmp->nm_disconcv);
831 		mutex_exit(&nmp->nm_lock);
832 
833 		if (error) {
834 			nfs_rcvunlock(nmp);
835 
836 			if (nmp->nm_iflag & NFSMNT_DISMNT) {
837 				/*
838 				 * Oops, we're going away now..
839 				 */
840 				return error;
841 			}
842 			/*
843 			 * Ignore routing errors on connectionless protocols? ?
844 			 */
845 			if (NFSIGNORE_SOERROR(nmp->nm_soflags, error)) {
846 				nmp->nm_so->so_error = 0;
847 #ifdef DEBUG
848 				printf("nfs_reply: ignoring error %d\n", error);
849 #endif
850 				continue;
851 			}
852 			return (error);
853 		}
854 		if (nam)
855 			m_freem(nam);
856 
857 		/*
858 		 * Get the xid and check that it is an rpc reply
859 		 */
860 		md = mrep;
861 		dpos = mtod(md, void *);
862 		nfsm_dissect(tl, u_int32_t *, 2*NFSX_UNSIGNED);
863 		rxid = *tl++;
864 		if (*tl != rpc_reply) {
865 			nfsstats.rpcinvalid++;
866 			m_freem(mrep);
867 nfsmout:
868 			nfs_rcvunlock(nmp);
869 			continue;
870 		}
871 
872 		/*
873 		 * Loop through the request list to match up the reply
874 		 * Iff no match, just drop the datagram
875 		 */
876 		TAILQ_FOREACH(rep, &nfs_reqq, r_chain) {
877 			if (rep->r_mrep == NULL && rxid == rep->r_xid) {
878 				/* Found it.. */
879 				rep->r_mrep = mrep;
880 				rep->r_md = md;
881 				rep->r_dpos = dpos;
882 				if (nfsrtton) {
883 					struct rttl *rt;
884 
885 					rt = &nfsrtt.rttl[nfsrtt.pos];
886 					rt->proc = rep->r_procnum;
887 					rt->rto = NFS_RTO(nmp, proct[rep->r_procnum]);
888 					rt->sent = nmp->nm_sent;
889 					rt->cwnd = nmp->nm_cwnd;
890 					rt->srtt = nmp->nm_srtt[proct[rep->r_procnum] - 1];
891 					rt->sdrtt = nmp->nm_sdrtt[proct[rep->r_procnum] - 1];
892 					rt->fsid = nmp->nm_mountp->mnt_stat.f_fsidx;
893 					getmicrotime(&rt->tstamp);
894 					if (rep->r_flags & R_TIMING)
895 						rt->rtt = rep->r_rtt;
896 					else
897 						rt->rtt = 1000000;
898 					nfsrtt.pos = (nfsrtt.pos + 1) % NFSRTTLOGSIZ;
899 				}
900 				/*
901 				 * Update congestion window.
902 				 * Do the additive increase of
903 				 * one rpc/rtt.
904 				 */
905 				if (nmp->nm_cwnd <= nmp->nm_sent) {
906 					nmp->nm_cwnd +=
907 					   (NFS_CWNDSCALE * NFS_CWNDSCALE +
908 					   (nmp->nm_cwnd >> 1)) / nmp->nm_cwnd;
909 					if (nmp->nm_cwnd > NFS_MAXCWND)
910 						nmp->nm_cwnd = NFS_MAXCWND;
911 				}
912 				rep->r_flags &= ~R_SENT;
913 				nmp->nm_sent -= NFS_CWNDSCALE;
914 				/*
915 				 * Update rtt using a gain of 0.125 on the mean
916 				 * and a gain of 0.25 on the deviation.
917 				 */
918 				if (rep->r_flags & R_TIMING) {
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 					t1 = rep->r_rtt + 1;
928 					t1 -= (NFS_SRTT(rep) >> 3);
929 					NFS_SRTT(rep) += t1;
930 					if (t1 < 0)
931 						t1 = -t1;
932 					t1 -= (NFS_SDRTT(rep) >> 2);
933 					NFS_SDRTT(rep) += t1;
934 				}
935 				nmp->nm_timeouts = 0;
936 				break;
937 			}
938 		}
939 		nfs_rcvunlock(nmp);
940 		/*
941 		 * If not matched to a request, drop it.
942 		 * If it's mine, get out.
943 		 */
944 		if (rep == 0) {
945 			nfsstats.rpcunexpected++;
946 			m_freem(mrep);
947 		} else if (rep == myrep) {
948 			if (rep->r_mrep == NULL)
949 				panic("nfsreply nil");
950 			return (0);
951 		}
952 	}
953 }
954 
955 /*
956  * nfs_request - goes something like this
957  *	- fill in request struct
958  *	- links it into list
959  *	- calls nfs_send() for first transmit
960  *	- calls nfs_receive() to get reply
961  *	- break down rpc header and return with nfs reply pointed to
962  *	  by mrep or error
963  * nb: always frees up mreq mbuf list
964  */
965 int
966 nfs_request(np, mrest, procnum, lwp, cred, mrp, mdp, dposp, rexmitp)
967 	struct nfsnode *np;
968 	struct mbuf *mrest;
969 	int procnum;
970 	struct lwp *lwp;
971 	kauth_cred_t cred;
972 	struct mbuf **mrp;
973 	struct mbuf **mdp;
974 	char **dposp;
975 	int *rexmitp;
976 {
977 	struct mbuf *m, *mrep;
978 	struct nfsreq *rep;
979 	u_int32_t *tl;
980 	int i;
981 	struct nfsmount *nmp = VFSTONFS(np->n_vnode->v_mount);
982 	struct mbuf *md, *mheadend;
983 	char nickv[RPCX_NICKVERF];
984 	time_t waituntil;
985 	char *dpos, *cp2;
986 	int t1, s, error = 0, mrest_len, auth_len, auth_type;
987 	int trylater_delay = NFS_TRYLATERDEL, failed_auth = 0;
988 	int verf_len, verf_type;
989 	u_int32_t xid;
990 	char *auth_str, *verf_str;
991 	NFSKERBKEY_T key;		/* save session key */
992 	kauth_cred_t acred;
993 	struct mbuf *mrest_backup = NULL;
994 	kauth_cred_t origcred = NULL; /* XXX: gcc */
995 	bool retry_cred = true;
996 	bool use_opencred = (np->n_flag & NUSEOPENCRED) != 0;
997 
998 	if (rexmitp != NULL)
999 		*rexmitp = 0;
1000 
1001 	acred = kauth_cred_alloc();
1002 
1003 tryagain_cred:
1004 	KASSERT(cred != NULL);
1005 	rep = kmem_alloc(sizeof(*rep), KM_SLEEP);
1006 	rep->r_nmp = nmp;
1007 	KASSERT(lwp == NULL || lwp == curlwp);
1008 	rep->r_lwp = lwp;
1009 	rep->r_procnum = procnum;
1010 	i = 0;
1011 	m = mrest;
1012 	while (m) {
1013 		i += m->m_len;
1014 		m = m->m_next;
1015 	}
1016 	mrest_len = i;
1017 
1018 	/*
1019 	 * Get the RPC header with authorization.
1020 	 */
1021 kerbauth:
1022 	verf_str = auth_str = (char *)0;
1023 	if (nmp->nm_flag & NFSMNT_KERB) {
1024 		verf_str = nickv;
1025 		verf_len = sizeof (nickv);
1026 		auth_type = RPCAUTH_KERB4;
1027 		memset((void *)key, 0, sizeof (key));
1028 		if (failed_auth || nfs_getnickauth(nmp, cred, &auth_str,
1029 			&auth_len, verf_str, verf_len)) {
1030 			error = nfs_getauth(nmp, rep, cred, &auth_str,
1031 				&auth_len, verf_str, &verf_len, key);
1032 			if (error) {
1033 				kmem_free(rep, sizeof(*rep));
1034 				m_freem(mrest);
1035 				KASSERT(kauth_cred_getrefcnt(acred) == 1);
1036 				kauth_cred_free(acred);
1037 				return (error);
1038 			}
1039 		}
1040 		retry_cred = false;
1041 	} else {
1042 		/* AUTH_UNIX */
1043 		uid_t uid;
1044 		gid_t gid;
1045 
1046 		/*
1047 		 * on the most unix filesystems, permission checks are
1048 		 * done when the file is open(2)'ed.
1049 		 * ie. once a file is successfully open'ed,
1050 		 * following i/o operations never fail with EACCES.
1051 		 * we try to follow the semantics as far as possible.
1052 		 *
1053 		 * note that we expect that the nfs server always grant
1054 		 * accesses by the file's owner.
1055 		 */
1056 		origcred = cred;
1057 		switch (procnum) {
1058 		case NFSPROC_READ:
1059 		case NFSPROC_WRITE:
1060 		case NFSPROC_COMMIT:
1061 			uid = np->n_vattr->va_uid;
1062 			gid = np->n_vattr->va_gid;
1063 			if (kauth_cred_geteuid(cred) == uid &&
1064 			    kauth_cred_getegid(cred) == gid) {
1065 				retry_cred = false;
1066 				break;
1067 			}
1068 			if (use_opencred)
1069 				break;
1070 			kauth_cred_setuid(acred, uid);
1071 			kauth_cred_seteuid(acred, uid);
1072 			kauth_cred_setsvuid(acred, uid);
1073 			kauth_cred_setgid(acred, gid);
1074 			kauth_cred_setegid(acred, gid);
1075 			kauth_cred_setsvgid(acred, gid);
1076 			cred = acred;
1077 			break;
1078 		default:
1079 			retry_cred = false;
1080 			break;
1081 		}
1082 		/*
1083 		 * backup mbuf chain if we can need it later to retry.
1084 		 *
1085 		 * XXX maybe we can keep a direct reference to
1086 		 * mrest without doing m_copym, but it's ...ugly.
1087 		 */
1088 		if (retry_cred)
1089 			mrest_backup = m_copym(mrest, 0, M_COPYALL, M_WAIT);
1090 		auth_type = RPCAUTH_UNIX;
1091 		/* XXX elad - ngroups */
1092 		auth_len = (((kauth_cred_ngroups(cred) > nmp->nm_numgrps) ?
1093 			nmp->nm_numgrps : kauth_cred_ngroups(cred)) << 2) +
1094 			5 * NFSX_UNSIGNED;
1095 	}
1096 	m = nfsm_rpchead(cred, nmp->nm_flag, procnum, auth_type, auth_len,
1097 	     auth_str, verf_len, verf_str, mrest, mrest_len, &mheadend, &xid);
1098 	if (auth_str)
1099 		free(auth_str, M_TEMP);
1100 
1101 	/*
1102 	 * For stream protocols, insert a Sun RPC Record Mark.
1103 	 */
1104 	if (nmp->nm_sotype == SOCK_STREAM) {
1105 		M_PREPEND(m, NFSX_UNSIGNED, M_WAIT);
1106 		*mtod(m, u_int32_t *) = htonl(0x80000000 |
1107 			 (m->m_pkthdr.len - NFSX_UNSIGNED));
1108 	}
1109 	rep->r_mreq = m;
1110 	rep->r_xid = xid;
1111 tryagain:
1112 	if (nmp->nm_flag & NFSMNT_SOFT)
1113 		rep->r_retry = nmp->nm_retry;
1114 	else
1115 		rep->r_retry = NFS_MAXREXMIT + 1;	/* past clip limit */
1116 	rep->r_rtt = rep->r_rexmit = 0;
1117 	if (proct[procnum] > 0)
1118 		rep->r_flags = R_TIMING;
1119 	else
1120 		rep->r_flags = 0;
1121 	rep->r_mrep = NULL;
1122 
1123 	/*
1124 	 * Do the client side RPC.
1125 	 */
1126 	nfsstats.rpcrequests++;
1127 	/*
1128 	 * Chain request into list of outstanding requests. Be sure
1129 	 * to put it LAST so timer finds oldest requests first.
1130 	 */
1131 	s = splsoftnet();
1132 	TAILQ_INSERT_TAIL(&nfs_reqq, rep, r_chain);
1133 	nfs_timer_start();
1134 
1135 	/*
1136 	 * If backing off another request or avoiding congestion, don't
1137 	 * send this one now but let timer do it. If not timing a request,
1138 	 * do it now.
1139 	 */
1140 	if (nmp->nm_so && (nmp->nm_sotype != SOCK_DGRAM ||
1141 	    (nmp->nm_flag & NFSMNT_DUMBTIMR) || nmp->nm_sent < nmp->nm_cwnd)) {
1142 		splx(s);
1143 		if (nmp->nm_soflags & PR_CONNREQUIRED)
1144 			error = nfs_sndlock(nmp, rep);
1145 		if (!error) {
1146 			m = m_copym(rep->r_mreq, 0, M_COPYALL, M_WAIT);
1147 			error = nfs_send(nmp->nm_so, nmp->nm_nam, m, rep, lwp);
1148 			if (nmp->nm_soflags & PR_CONNREQUIRED)
1149 				nfs_sndunlock(nmp);
1150 		}
1151 		if (!error && (rep->r_flags & R_MUSTRESEND) == 0) {
1152 			nmp->nm_sent += NFS_CWNDSCALE;
1153 			rep->r_flags |= R_SENT;
1154 		}
1155 	} else {
1156 		splx(s);
1157 		rep->r_rtt = -1;
1158 	}
1159 
1160 	/*
1161 	 * Wait for the reply from our send or the timer's.
1162 	 */
1163 	if (!error || error == EPIPE)
1164 		error = nfs_reply(rep, lwp);
1165 
1166 	/*
1167 	 * RPC done, unlink the request.
1168 	 */
1169 	s = splsoftnet();
1170 	TAILQ_REMOVE(&nfs_reqq, rep, r_chain);
1171 	splx(s);
1172 
1173 	/*
1174 	 * Decrement the outstanding request count.
1175 	 */
1176 	if (rep->r_flags & R_SENT) {
1177 		rep->r_flags &= ~R_SENT;	/* paranoia */
1178 		nmp->nm_sent -= NFS_CWNDSCALE;
1179 	}
1180 
1181 	if (rexmitp != NULL) {
1182 		int rexmit;
1183 
1184 		if (nmp->nm_sotype != SOCK_DGRAM)
1185 			rexmit = (rep->r_flags & R_REXMITTED) != 0;
1186 		else
1187 			rexmit = rep->r_rexmit;
1188 		*rexmitp = rexmit;
1189 	}
1190 
1191 	/*
1192 	 * If there was a successful reply and a tprintf msg.
1193 	 * tprintf a response.
1194 	 */
1195 	if (!error && (rep->r_flags & R_TPRINTFMSG))
1196 		nfs_msg(rep->r_lwp, nmp->nm_mountp->mnt_stat.f_mntfromname,
1197 		    "is alive again");
1198 	mrep = rep->r_mrep;
1199 	md = rep->r_md;
1200 	dpos = rep->r_dpos;
1201 	if (error)
1202 		goto nfsmout;
1203 
1204 	/*
1205 	 * break down the rpc header and check if ok
1206 	 */
1207 	nfsm_dissect(tl, u_int32_t *, 3 * NFSX_UNSIGNED);
1208 	if (*tl++ == rpc_msgdenied) {
1209 		if (*tl == rpc_mismatch)
1210 			error = EOPNOTSUPP;
1211 		else if ((nmp->nm_flag & NFSMNT_KERB) && *tl++ == rpc_autherr) {
1212 			if (!failed_auth) {
1213 				failed_auth++;
1214 				mheadend->m_next = (struct mbuf *)0;
1215 				m_freem(mrep);
1216 				m_freem(rep->r_mreq);
1217 				goto kerbauth;
1218 			} else
1219 				error = EAUTH;
1220 		} else
1221 			error = EACCES;
1222 		m_freem(mrep);
1223 		goto nfsmout;
1224 	}
1225 
1226 	/*
1227 	 * Grab any Kerberos verifier, otherwise just throw it away.
1228 	 */
1229 	verf_type = fxdr_unsigned(int, *tl++);
1230 	i = fxdr_unsigned(int32_t, *tl);
1231 	if ((nmp->nm_flag & NFSMNT_KERB) && verf_type == RPCAUTH_KERB4) {
1232 		error = nfs_savenickauth(nmp, cred, i, key, &md, &dpos, mrep);
1233 		if (error)
1234 			goto nfsmout;
1235 	} else if (i > 0)
1236 		nfsm_adv(nfsm_rndup(i));
1237 	nfsm_dissect(tl, u_int32_t *, NFSX_UNSIGNED);
1238 	/* 0 == ok */
1239 	if (*tl == 0) {
1240 		nfsm_dissect(tl, u_int32_t *, NFSX_UNSIGNED);
1241 		if (*tl != 0) {
1242 			error = fxdr_unsigned(int, *tl);
1243 			switch (error) {
1244 			case NFSERR_PERM:
1245 				error = EPERM;
1246 				break;
1247 
1248 			case NFSERR_NOENT:
1249 				error = ENOENT;
1250 				break;
1251 
1252 			case NFSERR_IO:
1253 				error = EIO;
1254 				break;
1255 
1256 			case NFSERR_NXIO:
1257 				error = ENXIO;
1258 				break;
1259 
1260 			case NFSERR_ACCES:
1261 				error = EACCES;
1262 				if (!retry_cred)
1263 					break;
1264 				m_freem(mrep);
1265 				m_freem(rep->r_mreq);
1266 				kmem_free(rep, sizeof(*rep));
1267 				use_opencred = !use_opencred;
1268 				if (mrest_backup == NULL) {
1269 					/* m_copym failure */
1270 					KASSERT(
1271 					    kauth_cred_getrefcnt(acred) == 1);
1272 					kauth_cred_free(acred);
1273 					return ENOMEM;
1274 				}
1275 				mrest = mrest_backup;
1276 				mrest_backup = NULL;
1277 				cred = origcred;
1278 				error = 0;
1279 				retry_cred = false;
1280 				goto tryagain_cred;
1281 
1282 			case NFSERR_EXIST:
1283 				error = EEXIST;
1284 				break;
1285 
1286 			case NFSERR_XDEV:
1287 				error = EXDEV;
1288 				break;
1289 
1290 			case NFSERR_NODEV:
1291 				error = ENODEV;
1292 				break;
1293 
1294 			case NFSERR_NOTDIR:
1295 				error = ENOTDIR;
1296 				break;
1297 
1298 			case NFSERR_ISDIR:
1299 				error = EISDIR;
1300 				break;
1301 
1302 			case NFSERR_INVAL:
1303 				error = EINVAL;
1304 				break;
1305 
1306 			case NFSERR_FBIG:
1307 				error = EFBIG;
1308 				break;
1309 
1310 			case NFSERR_NOSPC:
1311 				error = ENOSPC;
1312 				break;
1313 
1314 			case NFSERR_ROFS:
1315 				error = EROFS;
1316 				break;
1317 
1318 			case NFSERR_MLINK:
1319 				error = EMLINK;
1320 				break;
1321 
1322 			case NFSERR_TIMEDOUT:
1323 				error = ETIMEDOUT;
1324 				break;
1325 
1326 			case NFSERR_NAMETOL:
1327 				error = ENAMETOOLONG;
1328 				break;
1329 
1330 			case NFSERR_NOTEMPTY:
1331 				error = ENOTEMPTY;
1332 				break;
1333 
1334 			case NFSERR_DQUOT:
1335 				error = EDQUOT;
1336 				break;
1337 
1338 			case NFSERR_STALE:
1339 				/*
1340 				 * If the File Handle was stale, invalidate the
1341 				 * lookup cache, just in case.
1342 				 */
1343 				error = ESTALE;
1344 				cache_purge(NFSTOV(np));
1345 				break;
1346 
1347 			case NFSERR_REMOTE:
1348 				error = EREMOTE;
1349 				break;
1350 
1351 			case NFSERR_WFLUSH:
1352 			case NFSERR_BADHANDLE:
1353 			case NFSERR_NOT_SYNC:
1354 			case NFSERR_BAD_COOKIE:
1355 				error = EINVAL;
1356 				break;
1357 
1358 			case NFSERR_NOTSUPP:
1359 				error = ENOTSUP;
1360 				break;
1361 
1362 			case NFSERR_TOOSMALL:
1363 			case NFSERR_SERVERFAULT:
1364 			case NFSERR_BADTYPE:
1365 				error = EINVAL;
1366 				break;
1367 
1368 			case NFSERR_TRYLATER:
1369 				if ((nmp->nm_flag & NFSMNT_NFSV3) == 0)
1370 					break;
1371 				m_freem(mrep);
1372 				error = 0;
1373 				waituntil = time_second + trylater_delay;
1374 				while (time_second < waituntil) {
1375 					kpause("nfstrylater", false, hz, NULL);
1376 				}
1377 				trylater_delay *= NFS_TRYLATERDELMUL;
1378 				if (trylater_delay > NFS_TRYLATERDELMAX)
1379 					trylater_delay = NFS_TRYLATERDELMAX;
1380 				/*
1381 				 * RFC1813:
1382 				 * The client should wait and then try
1383 				 * the request with a new RPC transaction ID.
1384 				 */
1385 				nfs_renewxid(rep);
1386 				goto tryagain;
1387 
1388 			default:
1389 #ifdef DIAGNOSTIC
1390 				printf("Invalid rpc error code %d\n", error);
1391 #endif
1392 				error = EINVAL;
1393 				break;
1394 			}
1395 
1396 			if (nmp->nm_flag & NFSMNT_NFSV3) {
1397 				*mrp = mrep;
1398 				*mdp = md;
1399 				*dposp = dpos;
1400 				error |= NFSERR_RETERR;
1401 			} else
1402 				m_freem(mrep);
1403 			goto nfsmout;
1404 		}
1405 
1406 		/*
1407 		 * note which credential worked to minimize number of retries.
1408 		 */
1409 		if (use_opencred)
1410 			np->n_flag |= NUSEOPENCRED;
1411 		else
1412 			np->n_flag &= ~NUSEOPENCRED;
1413 
1414 		*mrp = mrep;
1415 		*mdp = md;
1416 		*dposp = dpos;
1417 
1418 		KASSERT(error == 0);
1419 		goto nfsmout;
1420 	}
1421 	m_freem(mrep);
1422 	error = EPROTONOSUPPORT;
1423 nfsmout:
1424 	KASSERT(kauth_cred_getrefcnt(acred) == 1);
1425 	kauth_cred_free(acred);
1426 	m_freem(rep->r_mreq);
1427 	kmem_free(rep, sizeof(*rep));
1428 	m_freem(mrest_backup);
1429 	return (error);
1430 }
1431 #endif /* NFS */
1432 
1433 /*
1434  * Generate the rpc reply header
1435  * siz arg. is used to decide if adding a cluster is worthwhile
1436  */
1437 int
1438 nfs_rephead(siz, nd, slp, err, cache, frev, mrq, mbp, bposp)
1439 	int siz;
1440 	struct nfsrv_descript *nd;
1441 	struct nfssvc_sock *slp;
1442 	int err;
1443 	int cache;
1444 	u_quad_t *frev;
1445 	struct mbuf **mrq;
1446 	struct mbuf **mbp;
1447 	char **bposp;
1448 {
1449 	u_int32_t *tl;
1450 	struct mbuf *mreq;
1451 	char *bpos;
1452 	struct mbuf *mb;
1453 
1454 	mreq = m_gethdr(M_WAIT, MT_DATA);
1455 	MCLAIM(mreq, &nfs_mowner);
1456 	mb = mreq;
1457 	/*
1458 	 * If this is a big reply, use a cluster else
1459 	 * try and leave leading space for the lower level headers.
1460 	 */
1461 	siz += RPC_REPLYSIZ;
1462 	if (siz >= max_datalen) {
1463 		m_clget(mreq, M_WAIT);
1464 	} else
1465 		mreq->m_data += max_hdr;
1466 	tl = mtod(mreq, u_int32_t *);
1467 	mreq->m_len = 6 * NFSX_UNSIGNED;
1468 	bpos = ((char *)tl) + mreq->m_len;
1469 	*tl++ = txdr_unsigned(nd->nd_retxid);
1470 	*tl++ = rpc_reply;
1471 	if (err == ERPCMISMATCH || (err & NFSERR_AUTHERR)) {
1472 		*tl++ = rpc_msgdenied;
1473 		if (err & NFSERR_AUTHERR) {
1474 			*tl++ = rpc_autherr;
1475 			*tl = txdr_unsigned(err & ~NFSERR_AUTHERR);
1476 			mreq->m_len -= NFSX_UNSIGNED;
1477 			bpos -= NFSX_UNSIGNED;
1478 		} else {
1479 			*tl++ = rpc_mismatch;
1480 			*tl++ = txdr_unsigned(RPC_VER2);
1481 			*tl = txdr_unsigned(RPC_VER2);
1482 		}
1483 	} else {
1484 		*tl++ = rpc_msgaccepted;
1485 
1486 		/*
1487 		 * For Kerberos authentication, we must send the nickname
1488 		 * verifier back, otherwise just RPCAUTH_NULL.
1489 		 */
1490 		if (nd->nd_flag & ND_KERBFULL) {
1491 			struct nfsuid *nuidp;
1492 			struct timeval ktvin, ktvout;
1493 
1494 			memset(&ktvout, 0, sizeof ktvout);	/* XXX gcc */
1495 
1496 			LIST_FOREACH(nuidp,
1497 			    NUIDHASH(slp, kauth_cred_geteuid(nd->nd_cr)),
1498 			    nu_hash) {
1499 				if (kauth_cred_geteuid(nuidp->nu_cr) ==
1500 				kauth_cred_geteuid(nd->nd_cr) &&
1501 				    (!nd->nd_nam2 || netaddr_match(
1502 				    NU_NETFAM(nuidp), &nuidp->nu_haddr,
1503 				    nd->nd_nam2)))
1504 					break;
1505 			}
1506 			if (nuidp) {
1507 				ktvin.tv_sec =
1508 				    txdr_unsigned(nuidp->nu_timestamp.tv_sec
1509 					- 1);
1510 				ktvin.tv_usec =
1511 				    txdr_unsigned(nuidp->nu_timestamp.tv_usec);
1512 
1513 				/*
1514 				 * Encrypt the timestamp in ecb mode using the
1515 				 * session key.
1516 				 */
1517 #ifdef NFSKERB
1518 				XXX
1519 #endif
1520 
1521 				*tl++ = rpc_auth_kerb;
1522 				*tl++ = txdr_unsigned(3 * NFSX_UNSIGNED);
1523 				*tl = ktvout.tv_sec;
1524 				nfsm_build(tl, u_int32_t *, 3 * NFSX_UNSIGNED);
1525 				*tl++ = ktvout.tv_usec;
1526 				*tl++ = txdr_unsigned(
1527 				    kauth_cred_geteuid(nuidp->nu_cr));
1528 			} else {
1529 				*tl++ = 0;
1530 				*tl++ = 0;
1531 			}
1532 		} else {
1533 			*tl++ = 0;
1534 			*tl++ = 0;
1535 		}
1536 		switch (err) {
1537 		case EPROGUNAVAIL:
1538 			*tl = txdr_unsigned(RPC_PROGUNAVAIL);
1539 			break;
1540 		case EPROGMISMATCH:
1541 			*tl = txdr_unsigned(RPC_PROGMISMATCH);
1542 			nfsm_build(tl, u_int32_t *, 2 * NFSX_UNSIGNED);
1543 			*tl++ = txdr_unsigned(2);
1544 			*tl = txdr_unsigned(3);
1545 			break;
1546 		case EPROCUNAVAIL:
1547 			*tl = txdr_unsigned(RPC_PROCUNAVAIL);
1548 			break;
1549 		case EBADRPC:
1550 			*tl = txdr_unsigned(RPC_GARBAGE);
1551 			break;
1552 		default:
1553 			*tl = 0;
1554 			if (err != NFSERR_RETVOID) {
1555 				nfsm_build(tl, u_int32_t *, NFSX_UNSIGNED);
1556 				if (err)
1557 				    *tl = txdr_unsigned(nfsrv_errmap(nd, err));
1558 				else
1559 				    *tl = 0;
1560 			}
1561 			break;
1562 		};
1563 	}
1564 
1565 	if (mrq != NULL)
1566 		*mrq = mreq;
1567 	*mbp = mb;
1568 	*bposp = bpos;
1569 	if (err != 0 && err != NFSERR_RETVOID)
1570 		nfsstats.srvrpc_errs++;
1571 	return (0);
1572 }
1573 
1574 static void
1575 nfs_timer_schedule(void)
1576 {
1577 
1578 	callout_schedule(&nfs_timer_ch, nfs_ticks);
1579 }
1580 
1581 void
1582 nfs_timer_start(void)
1583 {
1584 
1585 	if (callout_pending(&nfs_timer_ch))
1586 		return;
1587 
1588 	nfs_timer_start_ev.ev_count++;
1589 	nfs_timer_schedule();
1590 }
1591 
1592 void
1593 nfs_timer_init(void)
1594 {
1595 
1596 	callout_init(&nfs_timer_ch, 0);
1597 	callout_setfunc(&nfs_timer_ch, nfs_timer, NULL);
1598 	evcnt_attach_dynamic(&nfs_timer_ev, EVCNT_TYPE_MISC, NULL,
1599 	    "nfs", "timer");
1600 	evcnt_attach_dynamic(&nfs_timer_start_ev, EVCNT_TYPE_MISC, NULL,
1601 	    "nfs", "timer start");
1602 	evcnt_attach_dynamic(&nfs_timer_stop_ev, EVCNT_TYPE_MISC, NULL,
1603 	    "nfs", "timer stop");
1604 }
1605 
1606 /*
1607  * Nfs timer routine
1608  * Scan the nfsreq list and retranmit any requests that have timed out
1609  * To avoid retransmission attempts on STREAM sockets (in the future) make
1610  * sure to set the r_retry field to 0 (implies nm_retry == 0).
1611  * A non-NULL argument means 'initialize'.
1612  */
1613 void
1614 nfs_timer(void *arg)
1615 {
1616 	struct nfsreq *rep;
1617 	struct mbuf *m;
1618 	struct socket *so;
1619 	struct nfsmount *nmp;
1620 	int timeo;
1621 	int s, error;
1622 	bool more = false;
1623 #ifdef NFSSERVER
1624 	struct timeval tv;
1625 	struct nfssvc_sock *slp;
1626 	u_quad_t cur_usec;
1627 #endif
1628 
1629 	nfs_timer_ev.ev_count++;
1630 
1631 	s = splsoftnet();
1632 	TAILQ_FOREACH(rep, &nfs_reqq, r_chain) {
1633 		more = true;
1634 		nmp = rep->r_nmp;
1635 		if (rep->r_mrep || (rep->r_flags & R_SOFTTERM))
1636 			continue;
1637 		if (nfs_sigintr(nmp, rep, rep->r_lwp)) {
1638 			rep->r_flags |= R_SOFTTERM;
1639 			continue;
1640 		}
1641 		if (rep->r_rtt >= 0) {
1642 			rep->r_rtt++;
1643 			if (nmp->nm_flag & NFSMNT_DUMBTIMR)
1644 				timeo = nmp->nm_timeo;
1645 			else
1646 				timeo = NFS_RTO(nmp, proct[rep->r_procnum]);
1647 			if (nmp->nm_timeouts > 0)
1648 				timeo *= nfs_backoff[nmp->nm_timeouts - 1];
1649 			if (rep->r_rtt <= timeo)
1650 				continue;
1651 			if (nmp->nm_timeouts <
1652 			    (sizeof(nfs_backoff) / sizeof(nfs_backoff[0])))
1653 				nmp->nm_timeouts++;
1654 		}
1655 		/*
1656 		 * Check for server not responding
1657 		 */
1658 		if ((rep->r_flags & R_TPRINTFMSG) == 0 &&
1659 		     rep->r_rexmit > nmp->nm_deadthresh) {
1660 			nfs_msg(rep->r_lwp,
1661 			    nmp->nm_mountp->mnt_stat.f_mntfromname,
1662 			    "not responding");
1663 			rep->r_flags |= R_TPRINTFMSG;
1664 		}
1665 		if (rep->r_rexmit >= rep->r_retry) {	/* too many */
1666 			nfsstats.rpctimeouts++;
1667 			rep->r_flags |= R_SOFTTERM;
1668 			continue;
1669 		}
1670 		if (nmp->nm_sotype != SOCK_DGRAM) {
1671 			if (++rep->r_rexmit > NFS_MAXREXMIT)
1672 				rep->r_rexmit = NFS_MAXREXMIT;
1673 			continue;
1674 		}
1675 		if ((so = nmp->nm_so) == NULL)
1676 			continue;
1677 
1678 		/*
1679 		 * If there is enough space and the window allows..
1680 		 *	Resend it
1681 		 * Set r_rtt to -1 in case we fail to send it now.
1682 		 */
1683 		solock(so);
1684 		rep->r_rtt = -1;
1685 		if (sbspace(&so->so_snd) >= rep->r_mreq->m_pkthdr.len &&
1686 		   ((nmp->nm_flag & NFSMNT_DUMBTIMR) ||
1687 		    (rep->r_flags & R_SENT) ||
1688 		    nmp->nm_sent < nmp->nm_cwnd) &&
1689 		   (m = m_copym(rep->r_mreq, 0, M_COPYALL, M_DONTWAIT))){
1690 		        if (so->so_state & SS_ISCONNECTED)
1691 			    error = (*so->so_proto->pr_usrreq)(so, PRU_SEND, m,
1692 			    (struct mbuf *)0, (struct mbuf *)0, (struct lwp *)0);
1693 			else
1694 			    error = (*so->so_proto->pr_usrreq)(so, PRU_SEND, m,
1695 			    nmp->nm_nam, (struct mbuf *)0, (struct lwp *)0);
1696 			if (error) {
1697 				if (NFSIGNORE_SOERROR(nmp->nm_soflags, error)) {
1698 #ifdef DEBUG
1699 					printf("nfs_timer: ignoring error %d\n",
1700 						error);
1701 #endif
1702 					so->so_error = 0;
1703 				}
1704 			} else {
1705 				/*
1706 				 * Iff first send, start timing
1707 				 * else turn timing off, backoff timer
1708 				 * and divide congestion window by 2.
1709 				 */
1710 				if (rep->r_flags & R_SENT) {
1711 					rep->r_flags &= ~R_TIMING;
1712 					if (++rep->r_rexmit > NFS_MAXREXMIT)
1713 						rep->r_rexmit = NFS_MAXREXMIT;
1714 					nmp->nm_cwnd >>= 1;
1715 					if (nmp->nm_cwnd < NFS_CWNDSCALE)
1716 						nmp->nm_cwnd = NFS_CWNDSCALE;
1717 					nfsstats.rpcretries++;
1718 				} else {
1719 					rep->r_flags |= R_SENT;
1720 					nmp->nm_sent += NFS_CWNDSCALE;
1721 				}
1722 				rep->r_rtt = 0;
1723 			}
1724 		}
1725 		sounlock(so);
1726 	}
1727 	splx(s);
1728 
1729 #ifdef NFSSERVER
1730 	/*
1731 	 * Scan the write gathering queues for writes that need to be
1732 	 * completed now.
1733 	 */
1734 	getmicrotime(&tv);
1735 	cur_usec = (u_quad_t)tv.tv_sec * 1000000 + (u_quad_t)tv.tv_usec;
1736 	mutex_enter(&nfsd_lock);
1737 	TAILQ_FOREACH(slp, &nfssvc_sockhead, ns_chain) {
1738 		struct nfsrv_descript *nd;
1739 
1740 		nd = LIST_FIRST(&slp->ns_tq);
1741 		if (nd != NULL) {
1742 			if (nd->nd_time <= cur_usec) {
1743 				nfsrv_wakenfsd_locked(slp);
1744 			}
1745 			more = true;
1746 		}
1747 	}
1748 	mutex_exit(&nfsd_lock);
1749 #endif /* NFSSERVER */
1750 	if (more) {
1751 		nfs_timer_schedule();
1752 	} else {
1753 		nfs_timer_stop_ev.ev_count++;
1754 	}
1755 }
1756 
1757 /*
1758  * Test for a termination condition pending on the process.
1759  * This is used for NFSMNT_INT mounts.
1760  */
1761 int
1762 nfs_sigintr(nmp, rep, l)
1763 	struct nfsmount *nmp;
1764 	struct nfsreq *rep;
1765 	struct lwp *l;
1766 {
1767 	sigset_t ss;
1768 
1769 	if (rep && (rep->r_flags & R_SOFTTERM))
1770 		return (EINTR);
1771 	if (!(nmp->nm_flag & NFSMNT_INT))
1772 		return (0);
1773 	if (l) {
1774 		sigpending1(l, &ss);
1775 #if 0
1776 		sigminusset(&l->l_proc->p_sigctx.ps_sigignore, &ss);
1777 #endif
1778 		if (sigismember(&ss, SIGINT) || sigismember(&ss, SIGTERM) ||
1779 		    sigismember(&ss, SIGKILL) || sigismember(&ss, SIGHUP) ||
1780 		    sigismember(&ss, SIGQUIT))
1781 			return (EINTR);
1782 	}
1783 	return (0);
1784 }
1785 
1786 /*
1787  * Lock a socket against others.
1788  * Necessary for STREAM sockets to ensure you get an entire rpc request/reply
1789  * and also to avoid race conditions between the processes with nfs requests
1790  * in progress when a reconnect is necessary.
1791  */
1792 static int
1793 nfs_sndlock(struct nfsmount *nmp, struct nfsreq *rep)
1794 {
1795 	struct lwp *l;
1796 	int timeo = 0;
1797 	bool catch = false;
1798 	int error = 0;
1799 
1800 	if (rep) {
1801 		l = rep->r_lwp;
1802 		if (rep->r_nmp->nm_flag & NFSMNT_INT)
1803 			catch = true;
1804 	} else
1805 		l = NULL;
1806 	mutex_enter(&nmp->nm_lock);
1807 	while ((nmp->nm_iflag & NFSMNT_SNDLOCK) != 0) {
1808 		if (rep && nfs_sigintr(rep->r_nmp, rep, l)) {
1809 			error = EINTR;
1810 			goto quit;
1811 		}
1812 		if (catch) {
1813 			cv_timedwait_sig(&nmp->nm_sndcv, &nmp->nm_lock, timeo);
1814 		} else {
1815 			cv_timedwait(&nmp->nm_sndcv, &nmp->nm_lock, timeo);
1816 		}
1817 		if (catch) {
1818 			catch = false;
1819 			timeo = 2 * hz;
1820 		}
1821 	}
1822 	nmp->nm_iflag |= NFSMNT_SNDLOCK;
1823 quit:
1824 	mutex_exit(&nmp->nm_lock);
1825 	return error;
1826 }
1827 
1828 /*
1829  * Unlock the stream socket for others.
1830  */
1831 static void
1832 nfs_sndunlock(struct nfsmount *nmp)
1833 {
1834 
1835 	mutex_enter(&nmp->nm_lock);
1836 	if ((nmp->nm_iflag & NFSMNT_SNDLOCK) == 0)
1837 		panic("nfs sndunlock");
1838 	nmp->nm_iflag &= ~NFSMNT_SNDLOCK;
1839 	cv_signal(&nmp->nm_sndcv);
1840 	mutex_exit(&nmp->nm_lock);
1841 }
1842 
1843 static int
1844 nfs_rcvlock(struct nfsmount *nmp, struct nfsreq *rep)
1845 {
1846 	int *flagp = &nmp->nm_iflag;
1847 	int slptimeo = 0;
1848 	bool catch;
1849 	int error = 0;
1850 
1851 	KASSERT(nmp == rep->r_nmp);
1852 
1853 	catch = (nmp->nm_flag & NFSMNT_INT) != 0;
1854 	mutex_enter(&nmp->nm_lock);
1855 	while (/* CONSTCOND */ true) {
1856 		if (*flagp & NFSMNT_DISMNT) {
1857 			cv_signal(&nmp->nm_disconcv);
1858 			error = EIO;
1859 			break;
1860 		}
1861 		/* If our reply was received while we were sleeping,
1862 		 * then just return without taking the lock to avoid a
1863 		 * situation where a single iod could 'capture' the
1864 		 * receive lock.
1865 		 */
1866 		if (rep->r_mrep != NULL) {
1867 			error = EALREADY;
1868 			break;
1869 		}
1870 		if (nfs_sigintr(rep->r_nmp, rep, rep->r_lwp)) {
1871 			error = EINTR;
1872 			break;
1873 		}
1874 		if ((*flagp & NFSMNT_RCVLOCK) == 0) {
1875 			*flagp |= NFSMNT_RCVLOCK;
1876 			break;
1877 		}
1878 		if (catch) {
1879 			cv_timedwait_sig(&nmp->nm_rcvcv, &nmp->nm_lock,
1880 			    slptimeo);
1881 		} else {
1882 			cv_timedwait(&nmp->nm_rcvcv, &nmp->nm_lock,
1883 			    slptimeo);
1884 		}
1885 		if (catch) {
1886 			catch = false;
1887 			slptimeo = 2 * hz;
1888 		}
1889 	}
1890 	mutex_exit(&nmp->nm_lock);
1891 	return error;
1892 }
1893 
1894 /*
1895  * Unlock the stream socket for others.
1896  */
1897 static void
1898 nfs_rcvunlock(struct nfsmount *nmp)
1899 {
1900 
1901 	mutex_enter(&nmp->nm_lock);
1902 	if ((nmp->nm_iflag & NFSMNT_RCVLOCK) == 0)
1903 		panic("nfs rcvunlock");
1904 	nmp->nm_iflag &= ~NFSMNT_RCVLOCK;
1905 	cv_broadcast(&nmp->nm_rcvcv);
1906 	mutex_exit(&nmp->nm_lock);
1907 }
1908 
1909 /*
1910  * Parse an RPC request
1911  * - verify it
1912  * - allocate and fill in the cred.
1913  */
1914 int
1915 nfs_getreq(nd, nfsd, has_header)
1916 	struct nfsrv_descript *nd;
1917 	struct nfsd *nfsd;
1918 	int has_header;
1919 {
1920 	int len, i;
1921 	u_int32_t *tl;
1922 	int32_t t1;
1923 	struct uio uio;
1924 	struct iovec iov;
1925 	char *dpos, *cp2, *cp;
1926 	u_int32_t nfsvers, auth_type;
1927 	uid_t nickuid;
1928 	int error = 0, ticklen;
1929 	struct mbuf *mrep, *md;
1930 	struct nfsuid *nuidp;
1931 	struct timeval tvin, tvout;
1932 
1933 	memset(&tvout, 0, sizeof tvout);	/* XXX gcc */
1934 
1935 	KASSERT(nd->nd_cr == NULL);
1936 	mrep = nd->nd_mrep;
1937 	md = nd->nd_md;
1938 	dpos = nd->nd_dpos;
1939 	if (has_header) {
1940 		nfsm_dissect(tl, u_int32_t *, 10 * NFSX_UNSIGNED);
1941 		nd->nd_retxid = fxdr_unsigned(u_int32_t, *tl++);
1942 		if (*tl++ != rpc_call) {
1943 			m_freem(mrep);
1944 			return (EBADRPC);
1945 		}
1946 	} else
1947 		nfsm_dissect(tl, u_int32_t *, 8 * NFSX_UNSIGNED);
1948 	nd->nd_repstat = 0;
1949 	nd->nd_flag = 0;
1950 	if (*tl++ != rpc_vers) {
1951 		nd->nd_repstat = ERPCMISMATCH;
1952 		nd->nd_procnum = NFSPROC_NOOP;
1953 		return (0);
1954 	}
1955 	if (*tl != nfs_prog) {
1956 		nd->nd_repstat = EPROGUNAVAIL;
1957 		nd->nd_procnum = NFSPROC_NOOP;
1958 		return (0);
1959 	}
1960 	tl++;
1961 	nfsvers = fxdr_unsigned(u_int32_t, *tl++);
1962 	if (nfsvers < NFS_VER2 || nfsvers > NFS_VER3) {
1963 		nd->nd_repstat = EPROGMISMATCH;
1964 		nd->nd_procnum = NFSPROC_NOOP;
1965 		return (0);
1966 	}
1967 	if (nfsvers == NFS_VER3)
1968 		nd->nd_flag = ND_NFSV3;
1969 	nd->nd_procnum = fxdr_unsigned(u_int32_t, *tl++);
1970 	if (nd->nd_procnum == NFSPROC_NULL)
1971 		return (0);
1972 	if (nd->nd_procnum > NFSPROC_COMMIT ||
1973 	    (!nd->nd_flag && nd->nd_procnum > NFSV2PROC_STATFS)) {
1974 		nd->nd_repstat = EPROCUNAVAIL;
1975 		nd->nd_procnum = NFSPROC_NOOP;
1976 		return (0);
1977 	}
1978 	if ((nd->nd_flag & ND_NFSV3) == 0)
1979 		nd->nd_procnum = nfsv3_procid[nd->nd_procnum];
1980 	auth_type = *tl++;
1981 	len = fxdr_unsigned(int, *tl++);
1982 	if (len < 0 || len > RPCAUTH_MAXSIZ) {
1983 		m_freem(mrep);
1984 		return (EBADRPC);
1985 	}
1986 
1987 	nd->nd_flag &= ~ND_KERBAUTH;
1988 	/*
1989 	 * Handle auth_unix or auth_kerb.
1990 	 */
1991 	if (auth_type == rpc_auth_unix) {
1992 		uid_t uid;
1993 		gid_t gid;
1994 
1995 		nd->nd_cr = kauth_cred_alloc();
1996 		len = fxdr_unsigned(int, *++tl);
1997 		if (len < 0 || len > NFS_MAXNAMLEN) {
1998 			m_freem(mrep);
1999 			error = EBADRPC;
2000 			goto errout;
2001 		}
2002 		nfsm_adv(nfsm_rndup(len));
2003 		nfsm_dissect(tl, u_int32_t *, 3 * NFSX_UNSIGNED);
2004 
2005 		uid = fxdr_unsigned(uid_t, *tl++);
2006 		gid = fxdr_unsigned(gid_t, *tl++);
2007 		kauth_cred_setuid(nd->nd_cr, uid);
2008 		kauth_cred_seteuid(nd->nd_cr, uid);
2009 		kauth_cred_setsvuid(nd->nd_cr, uid);
2010 		kauth_cred_setgid(nd->nd_cr, gid);
2011 		kauth_cred_setegid(nd->nd_cr, gid);
2012 		kauth_cred_setsvgid(nd->nd_cr, gid);
2013 
2014 		len = fxdr_unsigned(int, *tl);
2015 		if (len < 0 || len > RPCAUTH_UNIXGIDS) {
2016 			m_freem(mrep);
2017 			error = EBADRPC;
2018 			goto errout;
2019 		}
2020 		nfsm_dissect(tl, u_int32_t *, (len + 2) * NFSX_UNSIGNED);
2021 
2022 		if (len > 0) {
2023 			size_t grbuf_size = min(len, NGROUPS) * sizeof(gid_t);
2024 			gid_t *grbuf = kmem_alloc(grbuf_size, KM_SLEEP);
2025 
2026 			for (i = 0; i < len; i++) {
2027 				if (i < NGROUPS) /* XXX elad */
2028 					grbuf[i] = fxdr_unsigned(gid_t, *tl++);
2029 				else
2030 					tl++;
2031 			}
2032 			kauth_cred_setgroups(nd->nd_cr, grbuf,
2033 			    min(len, NGROUPS), -1, UIO_SYSSPACE);
2034 			kmem_free(grbuf, grbuf_size);
2035 		}
2036 
2037 		len = fxdr_unsigned(int, *++tl);
2038 		if (len < 0 || len > RPCAUTH_MAXSIZ) {
2039 			m_freem(mrep);
2040 			error = EBADRPC;
2041 			goto errout;
2042 		}
2043 		if (len > 0)
2044 			nfsm_adv(nfsm_rndup(len));
2045 	} else if (auth_type == rpc_auth_kerb) {
2046 		switch (fxdr_unsigned(int, *tl++)) {
2047 		case RPCAKN_FULLNAME:
2048 			ticklen = fxdr_unsigned(int, *tl);
2049 			*((u_int32_t *)nfsd->nfsd_authstr) = *tl;
2050 			uio.uio_resid = nfsm_rndup(ticklen) + NFSX_UNSIGNED;
2051 			nfsd->nfsd_authlen = uio.uio_resid + NFSX_UNSIGNED;
2052 			if (uio.uio_resid > (len - 2 * NFSX_UNSIGNED)) {
2053 				m_freem(mrep);
2054 				error = EBADRPC;
2055 				goto errout;
2056 			}
2057 			uio.uio_offset = 0;
2058 			uio.uio_iov = &iov;
2059 			uio.uio_iovcnt = 1;
2060 			UIO_SETUP_SYSSPACE(&uio);
2061 			iov.iov_base = (void *)&nfsd->nfsd_authstr[4];
2062 			iov.iov_len = RPCAUTH_MAXSIZ - 4;
2063 			nfsm_mtouio(&uio, uio.uio_resid);
2064 			nfsm_dissect(tl, u_int32_t *, 2 * NFSX_UNSIGNED);
2065 			if (*tl++ != rpc_auth_kerb ||
2066 				fxdr_unsigned(int, *tl) != 4 * NFSX_UNSIGNED) {
2067 				printf("Bad kerb verifier\n");
2068 				nd->nd_repstat = (NFSERR_AUTHERR|AUTH_BADVERF);
2069 				nd->nd_procnum = NFSPROC_NOOP;
2070 				return (0);
2071 			}
2072 			nfsm_dissect(cp, void *, 4 * NFSX_UNSIGNED);
2073 			tl = (u_int32_t *)cp;
2074 			if (fxdr_unsigned(int, *tl) != RPCAKN_FULLNAME) {
2075 				printf("Not fullname kerb verifier\n");
2076 				nd->nd_repstat = (NFSERR_AUTHERR|AUTH_BADVERF);
2077 				nd->nd_procnum = NFSPROC_NOOP;
2078 				return (0);
2079 			}
2080 			cp += NFSX_UNSIGNED;
2081 			memcpy(nfsd->nfsd_verfstr, cp, 3 * NFSX_UNSIGNED);
2082 			nfsd->nfsd_verflen = 3 * NFSX_UNSIGNED;
2083 			nd->nd_flag |= ND_KERBFULL;
2084 			nfsd->nfsd_flag |= NFSD_NEEDAUTH;
2085 			break;
2086 		case RPCAKN_NICKNAME:
2087 			if (len != 2 * NFSX_UNSIGNED) {
2088 				printf("Kerb nickname short\n");
2089 				nd->nd_repstat = (NFSERR_AUTHERR|AUTH_BADCRED);
2090 				nd->nd_procnum = NFSPROC_NOOP;
2091 				return (0);
2092 			}
2093 			nickuid = fxdr_unsigned(uid_t, *tl);
2094 			nfsm_dissect(tl, u_int32_t *, 2 * NFSX_UNSIGNED);
2095 			if (*tl++ != rpc_auth_kerb ||
2096 				fxdr_unsigned(int, *tl) != 3 * NFSX_UNSIGNED) {
2097 				printf("Kerb nick verifier bad\n");
2098 				nd->nd_repstat = (NFSERR_AUTHERR|AUTH_BADVERF);
2099 				nd->nd_procnum = NFSPROC_NOOP;
2100 				return (0);
2101 			}
2102 			nfsm_dissect(tl, u_int32_t *, 3 * NFSX_UNSIGNED);
2103 			tvin.tv_sec = *tl++;
2104 			tvin.tv_usec = *tl;
2105 
2106 			LIST_FOREACH(nuidp, NUIDHASH(nfsd->nfsd_slp, nickuid),
2107 			    nu_hash) {
2108 				if (kauth_cred_geteuid(nuidp->nu_cr) == nickuid &&
2109 				    (!nd->nd_nam2 ||
2110 				     netaddr_match(NU_NETFAM(nuidp),
2111 				      &nuidp->nu_haddr, nd->nd_nam2)))
2112 					break;
2113 			}
2114 			if (!nuidp) {
2115 				nd->nd_repstat =
2116 					(NFSERR_AUTHERR|AUTH_REJECTCRED);
2117 				nd->nd_procnum = NFSPROC_NOOP;
2118 				return (0);
2119 			}
2120 
2121 			/*
2122 			 * Now, decrypt the timestamp using the session key
2123 			 * and validate it.
2124 			 */
2125 #ifdef NFSKERB
2126 			XXX
2127 #endif
2128 
2129 			tvout.tv_sec = fxdr_unsigned(long, tvout.tv_sec);
2130 			tvout.tv_usec = fxdr_unsigned(long, tvout.tv_usec);
2131 			if (nuidp->nu_expire < time_second ||
2132 			    nuidp->nu_timestamp.tv_sec > tvout.tv_sec ||
2133 			    (nuidp->nu_timestamp.tv_sec == tvout.tv_sec &&
2134 			     nuidp->nu_timestamp.tv_usec > tvout.tv_usec)) {
2135 				nuidp->nu_expire = 0;
2136 				nd->nd_repstat =
2137 				    (NFSERR_AUTHERR|AUTH_REJECTVERF);
2138 				nd->nd_procnum = NFSPROC_NOOP;
2139 				return (0);
2140 			}
2141 			kauth_cred_hold(nuidp->nu_cr);
2142 			nd->nd_cr = nuidp->nu_cr;
2143 			nd->nd_flag |= ND_KERBNICK;
2144 		}
2145 	} else {
2146 		nd->nd_repstat = (NFSERR_AUTHERR | AUTH_REJECTCRED);
2147 		nd->nd_procnum = NFSPROC_NOOP;
2148 		return (0);
2149 	}
2150 
2151 	nd->nd_md = md;
2152 	nd->nd_dpos = dpos;
2153 	KASSERT((nd->nd_cr == NULL && (nfsd->nfsd_flag & NFSD_NEEDAUTH) != 0)
2154 	     || (nd->nd_cr != NULL && (nfsd->nfsd_flag & NFSD_NEEDAUTH) == 0));
2155 	return (0);
2156 nfsmout:
2157 errout:
2158 	KASSERT(error != 0);
2159 	if (nd->nd_cr != NULL) {
2160 		kauth_cred_free(nd->nd_cr);
2161 		nd->nd_cr = NULL;
2162 	}
2163 	return (error);
2164 }
2165 
2166 int
2167 nfs_msg(l, server, msg)
2168 	struct lwp *l;
2169 	const char *server, *msg;
2170 {
2171 	tpr_t tpr;
2172 
2173 	if (l)
2174 		tpr = tprintf_open(l->l_proc);
2175 	else
2176 		tpr = NULL;
2177 	tprintf(tpr, "nfs server %s: %s\n", server, msg);
2178 	tprintf_close(tpr);
2179 	return (0);
2180 }
2181 
2182 #ifdef NFSSERVER
2183 int (*nfsrv3_procs[NFS_NPROCS]) __P((struct nfsrv_descript *,
2184 				    struct nfssvc_sock *, struct lwp *,
2185 				    struct mbuf **)) = {
2186 	nfsrv_null,
2187 	nfsrv_getattr,
2188 	nfsrv_setattr,
2189 	nfsrv_lookup,
2190 	nfsrv3_access,
2191 	nfsrv_readlink,
2192 	nfsrv_read,
2193 	nfsrv_write,
2194 	nfsrv_create,
2195 	nfsrv_mkdir,
2196 	nfsrv_symlink,
2197 	nfsrv_mknod,
2198 	nfsrv_remove,
2199 	nfsrv_rmdir,
2200 	nfsrv_rename,
2201 	nfsrv_link,
2202 	nfsrv_readdir,
2203 	nfsrv_readdirplus,
2204 	nfsrv_statfs,
2205 	nfsrv_fsinfo,
2206 	nfsrv_pathconf,
2207 	nfsrv_commit,
2208 	nfsrv_noop
2209 };
2210 
2211 /*
2212  * Socket upcall routine for the nfsd sockets.
2213  * The void *arg is a pointer to the "struct nfssvc_sock".
2214  */
2215 void
2216 nfsrv_soupcall(struct socket *so, void *arg, int waitflag)
2217 {
2218 	struct nfssvc_sock *slp = (struct nfssvc_sock *)arg;
2219 
2220 	nfsdsock_setbits(slp, SLP_A_NEEDQ);
2221 	nfsrv_wakenfsd(slp);
2222 }
2223 
2224 void
2225 nfsrv_rcv(struct nfssvc_sock *slp)
2226 {
2227 	struct socket *so;
2228 	struct mbuf *m;
2229 	struct mbuf *mp, *nam;
2230 	struct uio auio;
2231 	int flags;
2232 	int error;
2233 	int setflags = 0;
2234 
2235 	error = nfsdsock_lock(slp, true);
2236 	if (error) {
2237 		setflags |= SLP_A_NEEDQ;
2238 		goto dorecs_unlocked;
2239 	}
2240 
2241 	nfsdsock_clearbits(slp, SLP_A_NEEDQ);
2242 
2243 	so = slp->ns_so;
2244 	if (so->so_type == SOCK_STREAM) {
2245 		/*
2246 		 * Do soreceive().
2247 		 */
2248 		auio.uio_resid = 1000000000;
2249 		/* not need to setup uio_vmspace */
2250 		flags = MSG_DONTWAIT;
2251 		error = (*so->so_receive)(so, &nam, &auio, &mp, NULL, &flags);
2252 		if (error || mp == NULL) {
2253 			if (error == EWOULDBLOCK)
2254 				setflags |= SLP_A_NEEDQ;
2255 			else
2256 				setflags |= SLP_A_DISCONN;
2257 			goto dorecs;
2258 		}
2259 		m = mp;
2260 		m_claimm(m, &nfs_mowner);
2261 		if (slp->ns_rawend) {
2262 			slp->ns_rawend->m_next = m;
2263 			slp->ns_cc += 1000000000 - auio.uio_resid;
2264 		} else {
2265 			slp->ns_raw = m;
2266 			slp->ns_cc = 1000000000 - auio.uio_resid;
2267 		}
2268 		while (m->m_next)
2269 			m = m->m_next;
2270 		slp->ns_rawend = m;
2271 
2272 		/*
2273 		 * Now try and parse record(s) out of the raw stream data.
2274 		 */
2275 		error = nfsrv_getstream(slp, M_WAIT);
2276 		if (error) {
2277 			if (error == EPERM)
2278 				setflags |= SLP_A_DISCONN;
2279 			else
2280 				setflags |= SLP_A_NEEDQ;
2281 		}
2282 	} else {
2283 		do {
2284 			auio.uio_resid = 1000000000;
2285 			/* not need to setup uio_vmspace */
2286 			flags = MSG_DONTWAIT;
2287 			error = (*so->so_receive)(so, &nam, &auio, &mp, NULL,
2288 			    &flags);
2289 			if (mp) {
2290 				if (nam) {
2291 					m = nam;
2292 					m->m_next = mp;
2293 				} else
2294 					m = mp;
2295 				m_claimm(m, &nfs_mowner);
2296 				if (slp->ns_recend)
2297 					slp->ns_recend->m_nextpkt = m;
2298 				else
2299 					slp->ns_rec = m;
2300 				slp->ns_recend = m;
2301 				m->m_nextpkt = (struct mbuf *)0;
2302 			}
2303 			if (error) {
2304 				if ((so->so_proto->pr_flags & PR_CONNREQUIRED)
2305 				    && error != EWOULDBLOCK) {
2306 					setflags |= SLP_A_DISCONN;
2307 					goto dorecs;
2308 				}
2309 			}
2310 		} while (mp);
2311 	}
2312 dorecs:
2313 	nfsdsock_unlock(slp);
2314 
2315 dorecs_unlocked:
2316 	if (setflags) {
2317 		nfsdsock_setbits(slp, setflags);
2318 	}
2319 }
2320 
2321 int
2322 nfsdsock_lock(struct nfssvc_sock *slp, bool waitok)
2323 {
2324 
2325 	mutex_enter(&slp->ns_lock);
2326 	while ((~slp->ns_flags & (SLP_BUSY|SLP_VALID)) == 0) {
2327 		if (!waitok) {
2328 			mutex_exit(&slp->ns_lock);
2329 			return EWOULDBLOCK;
2330 		}
2331 		cv_wait(&slp->ns_cv, &slp->ns_lock);
2332 	}
2333 	if ((slp->ns_flags & SLP_VALID) == 0) {
2334 		mutex_exit(&slp->ns_lock);
2335 		return EINVAL;
2336 	}
2337 	KASSERT((slp->ns_flags & SLP_BUSY) == 0);
2338 	slp->ns_flags |= SLP_BUSY;
2339 	mutex_exit(&slp->ns_lock);
2340 
2341 	return 0;
2342 }
2343 
2344 void
2345 nfsdsock_unlock(struct nfssvc_sock *slp)
2346 {
2347 
2348 	mutex_enter(&slp->ns_lock);
2349 	KASSERT((slp->ns_flags & SLP_BUSY) != 0);
2350 	cv_broadcast(&slp->ns_cv);
2351 	slp->ns_flags &= ~SLP_BUSY;
2352 	mutex_exit(&slp->ns_lock);
2353 }
2354 
2355 int
2356 nfsdsock_drain(struct nfssvc_sock *slp)
2357 {
2358 	int error = 0;
2359 
2360 	mutex_enter(&slp->ns_lock);
2361 	if ((slp->ns_flags & SLP_VALID) == 0) {
2362 		error = EINVAL;
2363 		goto done;
2364 	}
2365 	slp->ns_flags &= ~SLP_VALID;
2366 	while ((slp->ns_flags & SLP_BUSY) != 0) {
2367 		cv_wait(&slp->ns_cv, &slp->ns_lock);
2368 	}
2369 done:
2370 	mutex_exit(&slp->ns_lock);
2371 
2372 	return error;
2373 }
2374 
2375 /*
2376  * Try and extract an RPC request from the mbuf data list received on a
2377  * stream socket. The "waitflag" argument indicates whether or not it
2378  * can sleep.
2379  */
2380 int
2381 nfsrv_getstream(slp, waitflag)
2382 	struct nfssvc_sock *slp;
2383 	int waitflag;
2384 {
2385 	struct mbuf *m, **mpp;
2386 	struct mbuf *recm;
2387 	u_int32_t recmark;
2388 	int error = 0;
2389 
2390 	KASSERT((slp->ns_flags & SLP_BUSY) != 0);
2391 	for (;;) {
2392 		if (slp->ns_reclen == 0) {
2393 			if (slp->ns_cc < NFSX_UNSIGNED) {
2394 				break;
2395 			}
2396 			m = slp->ns_raw;
2397 			m_copydata(m, 0, NFSX_UNSIGNED, (void *)&recmark);
2398 			m_adj(m, NFSX_UNSIGNED);
2399 			slp->ns_cc -= NFSX_UNSIGNED;
2400 			recmark = ntohl(recmark);
2401 			slp->ns_reclen = recmark & ~0x80000000;
2402 			if (recmark & 0x80000000)
2403 				slp->ns_sflags |= SLP_S_LASTFRAG;
2404 			else
2405 				slp->ns_sflags &= ~SLP_S_LASTFRAG;
2406 			if (slp->ns_reclen > NFS_MAXPACKET) {
2407 				error = EPERM;
2408 				break;
2409 			}
2410 		}
2411 
2412 		/*
2413 		 * Now get the record part.
2414 		 *
2415 		 * Note that slp->ns_reclen may be 0.  Linux sometimes
2416 		 * generates 0-length records.
2417 		 */
2418 		if (slp->ns_cc == slp->ns_reclen) {
2419 			recm = slp->ns_raw;
2420 			slp->ns_raw = slp->ns_rawend = (struct mbuf *)0;
2421 			slp->ns_cc = slp->ns_reclen = 0;
2422 		} else if (slp->ns_cc > slp->ns_reclen) {
2423 			recm = slp->ns_raw;
2424 			m = m_split(recm, slp->ns_reclen, waitflag);
2425 			if (m == NULL) {
2426 				error = EWOULDBLOCK;
2427 				break;
2428 			}
2429 			m_claimm(recm, &nfs_mowner);
2430 			slp->ns_raw = m;
2431 			if (m->m_next == NULL)
2432 				slp->ns_rawend = m;
2433 			slp->ns_cc -= slp->ns_reclen;
2434 			slp->ns_reclen = 0;
2435 		} else {
2436 			break;
2437 		}
2438 
2439 		/*
2440 		 * Accumulate the fragments into a record.
2441 		 */
2442 		mpp = &slp->ns_frag;
2443 		while (*mpp)
2444 			mpp = &((*mpp)->m_next);
2445 		*mpp = recm;
2446 		if (slp->ns_sflags & SLP_S_LASTFRAG) {
2447 			if (slp->ns_recend)
2448 				slp->ns_recend->m_nextpkt = slp->ns_frag;
2449 			else
2450 				slp->ns_rec = slp->ns_frag;
2451 			slp->ns_recend = slp->ns_frag;
2452 			slp->ns_frag = NULL;
2453 		}
2454 	}
2455 
2456 	return error;
2457 }
2458 
2459 /*
2460  * Parse an RPC header.
2461  */
2462 int
2463 nfsrv_dorec(struct nfssvc_sock *slp, struct nfsd *nfsd,
2464     struct nfsrv_descript **ndp, bool *more)
2465 {
2466 	struct mbuf *m, *nam;
2467 	struct nfsrv_descript *nd;
2468 	int error;
2469 
2470 	*ndp = NULL;
2471 	*more = false;
2472 
2473 	if (nfsdsock_lock(slp, true)) {
2474 		return ENOBUFS;
2475 	}
2476 	m = slp->ns_rec;
2477 	if (m == NULL) {
2478 		nfsdsock_unlock(slp);
2479 		return ENOBUFS;
2480 	}
2481 	slp->ns_rec = m->m_nextpkt;
2482 	if (slp->ns_rec) {
2483 		m->m_nextpkt = NULL;
2484 		*more = true;
2485 	} else {
2486 		slp->ns_recend = NULL;
2487 	}
2488 	nfsdsock_unlock(slp);
2489 
2490 	if (m->m_type == MT_SONAME) {
2491 		nam = m;
2492 		m = m->m_next;
2493 		nam->m_next = NULL;
2494 	} else
2495 		nam = NULL;
2496 	nd = nfsdreq_alloc();
2497 	nd->nd_md = nd->nd_mrep = m;
2498 	nd->nd_nam2 = nam;
2499 	nd->nd_dpos = mtod(m, void *);
2500 	error = nfs_getreq(nd, nfsd, true);
2501 	if (error) {
2502 		m_freem(nam);
2503 		nfsdreq_free(nd);
2504 		return (error);
2505 	}
2506 	*ndp = nd;
2507 	nfsd->nfsd_nd = nd;
2508 	return (0);
2509 }
2510 
2511 /*
2512  * Search for a sleeping nfsd and wake it up.
2513  * SIDE EFFECT: If none found, set NFSD_CHECKSLP flag, so that one of the
2514  * running nfsds will go look for the work in the nfssvc_sock list.
2515  */
2516 static void
2517 nfsrv_wakenfsd_locked(struct nfssvc_sock *slp)
2518 {
2519 	struct nfsd *nd;
2520 
2521 	KASSERT(mutex_owned(&nfsd_lock));
2522 
2523 	if ((slp->ns_flags & SLP_VALID) == 0)
2524 		return;
2525 	if (slp->ns_gflags & SLP_G_DOREC)
2526 		return;
2527 	nd = SLIST_FIRST(&nfsd_idle_head);
2528 	if (nd) {
2529 		SLIST_REMOVE_HEAD(&nfsd_idle_head, nfsd_idle);
2530 		if (nd->nfsd_slp)
2531 			panic("nfsd wakeup");
2532 		slp->ns_sref++;
2533 		KASSERT(slp->ns_sref > 0);
2534 		nd->nfsd_slp = slp;
2535 		cv_signal(&nd->nfsd_cv);
2536 	} else {
2537 		slp->ns_gflags |= SLP_G_DOREC;
2538 		nfsd_head_flag |= NFSD_CHECKSLP;
2539 		TAILQ_INSERT_TAIL(&nfssvc_sockpending, slp, ns_pending);
2540 	}
2541 }
2542 
2543 void
2544 nfsrv_wakenfsd(struct nfssvc_sock *slp)
2545 {
2546 
2547 	mutex_enter(&nfsd_lock);
2548 	nfsrv_wakenfsd_locked(slp);
2549 	mutex_exit(&nfsd_lock);
2550 }
2551 
2552 int
2553 nfsdsock_sendreply(struct nfssvc_sock *slp, struct nfsrv_descript *nd)
2554 {
2555 	int error;
2556 
2557 	if (nd->nd_mrep != NULL) {
2558 		m_freem(nd->nd_mrep);
2559 		nd->nd_mrep = NULL;
2560 	}
2561 
2562 	mutex_enter(&slp->ns_lock);
2563 	if ((slp->ns_flags & SLP_SENDING) != 0) {
2564 		SIMPLEQ_INSERT_TAIL(&slp->ns_sendq, nd, nd_sendq);
2565 		mutex_exit(&slp->ns_lock);
2566 		return 0;
2567 	}
2568 	KASSERT(SIMPLEQ_EMPTY(&slp->ns_sendq));
2569 	slp->ns_flags |= SLP_SENDING;
2570 	mutex_exit(&slp->ns_lock);
2571 
2572 again:
2573 	error = nfs_send(slp->ns_so, nd->nd_nam2, nd->nd_mreq, NULL, curlwp);
2574 	if (nd->nd_nam2) {
2575 		m_free(nd->nd_nam2);
2576 	}
2577 	nfsdreq_free(nd);
2578 
2579 	mutex_enter(&slp->ns_lock);
2580 	KASSERT((slp->ns_flags & SLP_SENDING) != 0);
2581 	nd = SIMPLEQ_FIRST(&slp->ns_sendq);
2582 	if (nd != NULL) {
2583 		SIMPLEQ_REMOVE_HEAD(&slp->ns_sendq, nd_sendq);
2584 		mutex_exit(&slp->ns_lock);
2585 		goto again;
2586 	}
2587 	slp->ns_flags &= ~SLP_SENDING;
2588 	mutex_exit(&slp->ns_lock);
2589 
2590 	return error;
2591 }
2592 
2593 void
2594 nfsdsock_setbits(struct nfssvc_sock *slp, int bits)
2595 {
2596 
2597 	mutex_enter(&slp->ns_alock);
2598 	slp->ns_aflags |= bits;
2599 	mutex_exit(&slp->ns_alock);
2600 }
2601 
2602 void
2603 nfsdsock_clearbits(struct nfssvc_sock *slp, int bits)
2604 {
2605 
2606 	mutex_enter(&slp->ns_alock);
2607 	slp->ns_aflags &= ~bits;
2608 	mutex_exit(&slp->ns_alock);
2609 }
2610 
2611 bool
2612 nfsdsock_testbits(struct nfssvc_sock *slp, int bits)
2613 {
2614 
2615 	return (slp->ns_aflags & bits);
2616 }
2617 #endif /* NFSSERVER */
2618 
2619 #if defined(NFSSERVER) || (defined(NFS) && !defined(NFS_V2_ONLY))
2620 static struct pool nfs_srvdesc_pool;
2621 
2622 void
2623 nfsdreq_init(void)
2624 {
2625 
2626 	pool_init(&nfs_srvdesc_pool, sizeof(struct nfsrv_descript),
2627 	    0, 0, 0, "nfsrvdescpl", &pool_allocator_nointr, IPL_NONE);
2628 }
2629 
2630 struct nfsrv_descript *
2631 nfsdreq_alloc(void)
2632 {
2633 	struct nfsrv_descript *nd;
2634 
2635 	nd = pool_get(&nfs_srvdesc_pool, PR_WAITOK);
2636 	nd->nd_cr = NULL;
2637 	return nd;
2638 }
2639 
2640 void
2641 nfsdreq_free(struct nfsrv_descript *nd)
2642 {
2643 	kauth_cred_t cr;
2644 
2645 	cr = nd->nd_cr;
2646 	if (cr != NULL) {
2647 		kauth_cred_free(cr);
2648 	}
2649 	pool_put(&nfs_srvdesc_pool, nd);
2650 }
2651 #endif /* defined(NFSSERVER) || (defined(NFS) && !defined(NFS_V2_ONLY)) */
2652