xref: /csrg-svn/sys/nfs/nfs_syscalls.c (revision 52196)
1 /*
2  * Copyright (c) 1989 The Regents of the University of California.
3  * 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  * %sccs.include.redist.c%
9  *
10  *	@(#)nfs_syscalls.c	7.27 (Berkeley) 01/14/92
11  */
12 
13 #include "param.h"
14 #include "systm.h"
15 #include "kernel.h"
16 #include "file.h"
17 #include "stat.h"
18 #include "vnode.h"
19 #include "mount.h"
20 #include "proc.h"
21 #include "uio.h"
22 #include "malloc.h"
23 #include "buf.h"
24 #include "mbuf.h"
25 #include "socket.h"
26 #include "socketvar.h"
27 #include "domain.h"
28 #include "protosw.h"
29 #include "namei.h"
30 #include "netinet/in.h"
31 #include "netinet/tcp.h"
32 #ifdef ISO
33 #include "netiso/iso.h"
34 #endif
35 #include "machine/endian.h"
36 #include "rpcv2.h"
37 #include "nfsv2.h"
38 #include "nfs.h"
39 #include "nfsrvcache.h"
40 #include "nfsmount.h"
41 #include "nqnfs.h"
42 
43 /* Global defs. */
44 extern u_long nfs_prog, nfs_vers;
45 extern int (*nfsrv_procs[NFS_NPROCS])();
46 extern struct buf nfs_bqueue;
47 extern struct proc *nfs_iodwant[NFS_MAXASYNCDAEMON];
48 extern int nfs_numasync;
49 extern time_t nqnfsstarttime;
50 extern struct nfsrv_req nsrvq_head;
51 extern struct nfsd nfsd_head;
52 extern int nqsrv_writeslack;
53 struct nfssvc_sock *nfs_udpsock, *nfs_cltpsock;
54 int nuidhash_max = NFS_MAXUIDHASH;
55 static int nfs_numnfsd = 0;
56 int nfsd_waiting = 0;
57 static int notstarted = 1;
58 static int modify_flag = 0;
59 void nfsrv_cleancache(), nfsrv_rcv(), nfsrv_wakenfsd(), nfs_sndunlock();
60 
61 #define	TRUE	1
62 #define	FALSE	0
63 
64 static int nfs_asyncdaemon[NFS_MAXASYNCDAEMON];
65 /*
66  * NFS server system calls
67  * getfh() lives here too, but maybe should move to kern/vfs_syscalls.c
68  */
69 
70 /*
71  * Get file handle system call
72  */
73 getfh(p, uap, retval)
74 	struct proc *p;
75 	register struct args {
76 		char	*fname;
77 		fhandle_t *fhp;
78 	} *uap;
79 	int *retval;
80 {
81 	register struct nameidata *ndp;
82 	register struct vnode *vp;
83 	fhandle_t fh;
84 	int error;
85 	struct nameidata nd;
86 
87 	/*
88 	 * Must be super user
89 	 */
90 	if (error = suser(p->p_ucred, &p->p_acflag))
91 		return (error);
92 	ndp = &nd;
93 	ndp->ni_nameiop = LOOKUP | LOCKLEAF | FOLLOW;
94 	ndp->ni_segflg = UIO_USERSPACE;
95 	ndp->ni_dirp = uap->fname;
96 	if (error = namei(ndp, p))
97 		return (error);
98 	vp = ndp->ni_vp;
99 	bzero((caddr_t)&fh, sizeof(fh));
100 	fh.fh_fsid = vp->v_mount->mnt_stat.f_fsid;
101 	error = VFS_VPTOFH(vp, &fh.fh_fid);
102 	vput(vp);
103 	if (error)
104 		return (error);
105 	error = copyout((caddr_t)&fh, (caddr_t)uap->fhp, sizeof (fh));
106 	return (error);
107 }
108 
109 static struct nfssvc_sock nfssvc_sockhead;
110 
111 /*
112  * Nfs server psuedo system call for the nfsd's
113  * Based on the flag value it either:
114  * - adds a socket to the selection list
115  * - remains in the kernel as an nfsd
116  * - remains in the kernel as an nfsiod
117  */
118 nfssvc(p, uap, retval)
119 	struct proc *p;
120 	register struct args {
121 		int flag;
122 		caddr_t argp;
123 	} *uap;
124 	int *retval;
125 {
126 	struct nameidata nd;
127 	struct file *fp;
128 	struct mbuf *nam;
129 	struct nfsd_args nfsdarg;
130 	struct nfsd_srvargs nfsd_srvargs, *nsd = &nfsd_srvargs;
131 	struct nfsd_cargs ncd;
132 	struct nfsd *nfsd;
133 	struct nfssvc_sock *slp;
134 	struct nfsuid *nuidp, **nuh;
135 	struct nfsmount *nmp;
136 	int error;
137 
138 	/*
139 	 * Must be super user
140 	 */
141 	if (error = suser(p->p_ucred, &p->p_acflag))
142 		return (error);
143 	if (nfssvc_sockhead.ns_next == NULL) {
144 		nfs_udpsock = (struct nfssvc_sock *)
145 		    malloc(sizeof (struct nfssvc_sock), M_NFSSVC, M_WAITOK);
146 		bzero((caddr_t)nfs_udpsock, sizeof (struct nfssvc_sock));
147 		nfs_cltpsock = (struct nfssvc_sock *)
148 		    malloc(sizeof (struct nfssvc_sock), M_NFSSVC, M_WAITOK);
149 		bzero((caddr_t)nfs_cltpsock, sizeof (struct nfssvc_sock));
150 		nfssvc_sockhead.ns_next = nfs_udpsock;
151 		nfs_udpsock->ns_next = nfs_cltpsock;
152 		nfs_cltpsock->ns_next = &nfssvc_sockhead;
153 		nfssvc_sockhead.ns_prev = nfs_cltpsock;
154 		nfs_cltpsock->ns_prev = nfs_udpsock;
155 		nfs_udpsock->ns_prev = &nfssvc_sockhead;
156 		nfs_udpsock->ns_lrunext = nfs_udpsock->ns_lruprev =
157 			(struct nfsuid *)nfs_udpsock;
158 		nfs_cltpsock->ns_lrunext = nfs_cltpsock->ns_lruprev =
159 			(struct nfsuid *)nfs_cltpsock;
160 		nfsd_head.nd_next = nfsd_head.nd_prev = &nfsd_head;
161 		nfsd_head.nd_flag = 0;
162 	}
163 	if (uap->flag & NFSSVC_BIOD)
164 		error = nfssvc_iod(p);
165 	else if (uap->flag & NFSSVC_MNTD) {
166 		if (error = copyin(uap->argp, (caddr_t)&ncd, sizeof (ncd)))
167 			return (error);
168 		nd.ni_nameiop = LOOKUP | FOLLOW | LOCKLEAF;
169 		nd.ni_segflg = UIO_USERSPACE;
170 		nd.ni_dirp = ncd.ncd_dirp;
171 		if (error = namei(&nd, p))
172 			return (error);
173 		if ((nd.ni_vp->v_flag & VROOT) == 0)
174 			error = EINVAL;
175 		nmp = VFSTONFS(nd.ni_vp->v_mount);
176 		vput(nd.ni_vp);
177 		if (error)
178 			return (error);
179 		else if (nmp->nm_flag & NFSMNT_MNTD)
180 			return (0);
181 		nmp->nm_flag |= NFSMNT_MNTD;
182 		error = nqnfs_clientd(nmp, p->p_ucred, &ncd, uap->flag, uap->argp, p);
183 	} else if (uap->flag & NFSSVC_ADDSOCK) {
184 		if (error = copyin(uap->argp, (caddr_t)&nfsdarg, sizeof (nfsdarg)))
185 			return (error);
186 		if (error = getsock(p->p_fd, nfsdarg.sock, &fp))
187 			return (error);
188 		/*
189 		 * Get the client address for connected sockets.
190 		 */
191 		if (nfsdarg.name == NULL || nfsdarg.namelen == 0)
192 			nam = (struct mbuf *)0;
193 		else if (error = sockargs(&nam, nfsdarg.name, nfsdarg.namelen,
194 			MT_SONAME))
195 			return (error);
196 		error = nfssvc_addsock(fp, nam);
197 	} else {
198 		if (error = copyin(uap->argp, (caddr_t)nsd, sizeof (*nsd)))
199 			return (error);
200 		if ((uap->flag & NFSSVC_AUTHIN) && (nfsd = nsd->nsd_nfsd) &&
201 			nfsd->nd_sref == nfsd->nd_slp->ns_sref) {
202 			slp = nfsd->nd_slp;
203 			if (slp->ns_numuids < nuidhash_max) {
204 				slp->ns_numuids++;
205 				nuidp = (struct nfsuid *)
206 				   malloc(sizeof (struct nfsuid), M_NFSUID, M_WAITOK);
207 			} else
208 				nuidp = (struct nfsuid *)0;
209 			if (slp->ns_sref != nfsd->nd_sref) {
210 			    if (nuidp)
211 				free((caddr_t)nuidp, M_NFSUID);
212 			} else {
213 			    if (nuidp == (struct nfsuid *)0) {
214 				nuidp = slp->ns_lruprev;
215 				remque(nuidp);
216 				if (nuidp->nu_hprev)
217 					nuidp->nu_hprev->nu_hnext = nuidp->nu_hnext;
218 				if (nuidp->nu_hnext)
219 					nuidp->nu_hnext->nu_hprev = nuidp->nu_hprev;
220 			    }
221 			    nuidp->nu_cr = nsd->nsd_cr;
222 			    nuidp->nu_cr.cr_ref = 1;
223 			    nuidp->nu_uid = nsd->nsd_uid;
224 			    insque(nuidp, (struct nfsuid *)slp);
225 			    nuh = &slp->ns_uidh[NUIDHASH(nsd->nsd_uid)];
226 			    if (nuidp->nu_hnext = *nuh)
227 				nuidp->nu_hnext->nu_hprev = nuidp;
228 			    nuidp->nu_hprev = (struct nfsuid *)0;
229 			    *nuh = nuidp;
230 			}
231 		}
232 		if ((uap->flag & NFSSVC_AUTHINFAIL) && (nfsd = nsd->nsd_nfsd))
233 			nfsd->nd_flag |= NFSD_AUTHFAIL;
234 		error = nfssvc_nfsd(nsd, uap->argp, p);
235 	}
236 	if (error == EINTR || error == ERESTART)
237 		error = 0;
238 	return (error);
239 }
240 
241 /*
242  * Adds a socket to the list for servicing by nfsds.
243  */
244 nfssvc_addsock(fp, mynam)
245 	struct file *fp;
246 	struct mbuf *mynam;
247 {
248 	register struct mbuf *m;
249 	register int siz;
250 	register struct nfssvc_sock *slp;
251 	register struct socket *so;
252 	struct nfssvc_sock *tslp;
253 	int error, s;
254 
255 	so = (struct socket *)fp->f_data;
256 	tslp = (struct nfssvc_sock *)0;
257 	/*
258 	 * Add it to the list, as required.
259 	 */
260 	if (so->so_proto->pr_protocol == IPPROTO_UDP) {
261 		tslp = nfs_udpsock;
262 		if (tslp->ns_flag & SLP_VALID) {
263 			m_freem(mynam);
264 			return (EPERM);
265 		}
266 #ifdef ISO
267 	} else if (so->so_proto->pr_protocol == ISOPROTO_CLTP) {
268 		tslp = nfs_cltpsock;
269 		if (tslp->ns_flag & SLP_VALID) {
270 			m_freem(mynam);
271 			return (EPERM);
272 		}
273 #endif /* ISO */
274 	} else {
275 		slp = nfs_cltpsock->ns_next;
276 		while (slp != &nfssvc_sockhead) {
277 			if ((slp->ns_flag & SLP_VALID) == 0) {
278 				tslp = slp;
279 				break;
280 			}
281 			slp = slp->ns_next;
282 		}
283 	}
284 	if (so->so_type == SOCK_STREAM)
285 		siz = NFS_MAXPACKET + sizeof (u_long);
286 	else
287 		siz = NFS_MAXPACKET;
288 	if (error = soreserve(so, siz, siz)) {
289 		m_freem(mynam);
290 		return (error);
291 	}
292 
293 	/*
294 	 * Set protocol specific options { for now TCP only } and
295 	 * reserve some space. For datagram sockets, this can get called
296 	 * repeatedly for the same socket, but that isn't harmful.
297 	 */
298 	if (so->so_type == SOCK_STREAM) {
299 		MGET(m, M_WAIT, MT_SOOPTS);
300 		*mtod(m, int *) = 1;
301 		m->m_len = sizeof(int);
302 		sosetopt(so, SOL_SOCKET, SO_KEEPALIVE, m);
303 	}
304 	if (so->so_proto->pr_domain->dom_family == AF_INET &&
305 	    so->so_proto->pr_protocol == IPPROTO_TCP) {
306 		MGET(m, M_WAIT, MT_SOOPTS);
307 		*mtod(m, int *) = 1;
308 		m->m_len = sizeof(int);
309 		sosetopt(so, IPPROTO_TCP, TCP_NODELAY, m);
310 	}
311 	so->so_rcv.sb_flags &= ~SB_NOINTR;
312 	so->so_rcv.sb_timeo = 0;
313 	so->so_snd.sb_flags &= ~SB_NOINTR;
314 	so->so_snd.sb_timeo = 0;
315 	if (tslp)
316 		slp = tslp;
317 	else {
318 		slp = (struct nfssvc_sock *)
319 			malloc(sizeof (struct nfssvc_sock), M_NFSSVC, M_WAITOK);
320 		bzero((caddr_t)slp, sizeof (struct nfssvc_sock));
321 		slp->ns_prev = nfssvc_sockhead.ns_prev;
322 		slp->ns_prev->ns_next = slp;
323 		slp->ns_next = &nfssvc_sockhead;
324 		nfssvc_sockhead.ns_prev = slp;
325 		slp->ns_lrunext = slp->ns_lruprev = (struct nfsuid *)slp;
326 	}
327 	slp->ns_so = so;
328 	slp->ns_nam = mynam;
329 	fp->f_count++;
330 	slp->ns_fp = fp;
331 	s = splnet();
332 	so->so_upcallarg = (caddr_t)slp;
333 	so->so_upcall = nfsrv_rcv;
334 	slp->ns_flag = (SLP_VALID | SLP_NEEDQ);
335 	nfsd_head.nd_flag |= NFSD_CHECKSLP;
336 	nfsrv_wakenfsd(slp);
337 	splx(s);
338 	return (0);
339 }
340 
341 /*
342  * Called by nfssvc() for nfsds. Just loops around servicing rpc requests
343  * until it is killed by a signal.
344  */
345 nfssvc_nfsd(nsd, argp, p)
346 	struct nfsd_srvargs *nsd;
347 	caddr_t argp;
348 	struct proc *p;
349 {
350 	register struct mbuf *m, *nam2;
351 	register int siz;
352 	register struct nfssvc_sock *slp;
353 	register struct socket *so;
354 	register int *solockp;
355 	struct nfsd *nd = nsd->nsd_nfsd;
356 	struct mbuf *mreq, *nam;
357 	int error, cacherep, s;
358 	int sotype;
359 
360 	if (nd == (struct nfsd *)0) {
361 		nsd->nsd_nfsd = nd = (struct nfsd *)
362 			malloc(sizeof (struct nfsd), M_NFSD, M_WAITOK);
363 		bzero((caddr_t)nd, sizeof (struct nfsd));
364 		nd->nd_cr.cr_ref = 1;
365 		nd->nd_procp = p;
366 		s = splnet();
367 		insque(nd, &nfsd_head);
368 		splx(s);
369 		nfs_numnfsd++;
370 	}
371 	/*
372 	 * Loop getting rpc requests until SIGKILL.
373 	 */
374 	for (;;) {
375 		if ((nd->nd_flag & NFSD_REQINPROG) == 0) {
376 			s = splnet();
377 			while (nd->nd_slp == (struct nfssvc_sock *)0 &&
378 				 (nfsd_head.nd_flag & NFSD_CHECKSLP) == 0) {
379 				nd->nd_flag |= NFSD_WAITING;
380 				nfsd_waiting++;
381 				if (tsleep((caddr_t)nd, PSOCK | PCATCH, "nfsd", 0)) {
382 					nfsd_waiting--;
383 					splx(s);
384 					goto done;
385 				}
386 				nfsd_waiting--;
387 			}
388 			if (nd->nd_slp == (struct nfssvc_sock *)0 &&
389 				(nfsd_head.nd_flag & NFSD_CHECKSLP)) {
390 				slp = nfssvc_sockhead.ns_next;
391 				while (slp != &nfssvc_sockhead) {
392 				    if ((slp->ns_flag & SLP_VALID) &&
393 					(slp->ns_flag & (SLP_NEEDQ | SLP_DISCONN))) {
394 					    nd->nd_slp = slp;
395 					    nd->nd_sref = slp->ns_sref;
396 					    break;
397 				    }
398 				    slp = slp->ns_next;
399 				}
400 				if (slp == &nfssvc_sockhead)
401 					nfsd_head.nd_flag &= ~NFSD_CHECKSLP;
402 			}
403 			if ((slp = nd->nd_slp) == (struct nfssvc_sock *)0) {
404 				splx(s);
405 				continue;
406 			}
407 			if (slp->ns_flag & SLP_DISCONN) {
408 				slp->ns_flag &= ~SLP_DISCONN;
409 				(void) nfs_sndlock(&slp->ns_solock,
410 					(struct nfsreq *)0);
411 				if (nd->nd_sref == slp->ns_sref)
412 					nfsrv_zapsock(slp, p);
413 				nfs_sndunlock(&slp->ns_solock);
414 				nd->nd_slp = (struct nfssvc_sock *)0;
415 				splx(s);
416 				continue;
417 			}
418 			if (slp->ns_flag & SLP_NEEDQ) {
419 				slp->ns_flag &= ~SLP_NEEDQ;
420 				(void) nfs_sndlock(&slp->ns_solock,
421 					(struct nfsreq *)0);
422 				if (nd->nd_sref == slp->ns_sref) {
423 				    if (slp->ns_so->so_rcv.sb_cc > 0)
424 					nfsrv_rcv(slp->ns_so, (caddr_t)slp,
425 						M_WAIT);
426 				    else if (slp->ns_so->so_type == SOCK_STREAM)
427 					(void) nfsrv_getstream(slp, M_WAIT);
428 				}
429 				nfs_sndunlock(&slp->ns_solock);
430 			}
431 			error = nfsrv_dorec(slp, nd);
432 			splx(s);
433 			if (error) {
434 				nd->nd_slp = (struct nfssvc_sock *)0;
435 				continue;
436 			}
437 			nd->nd_flag |= NFSD_REQINPROG;
438 		} else
439 			slp = nd->nd_slp;
440 		so = slp->ns_so;
441 		sotype = so->so_type;
442 
443 		/*
444 		 * Check to see if authorization is needed.
445 		 */
446 		if (nd->nd_flag & NFSD_NEEDAUTH) {
447 			nd->nd_flag &= ~NFSD_NEEDAUTH;
448 			nsd->nsd_uid = nd->nd_cr.cr_uid;
449 			nsd->nsd_haddr =
450 			    mtod(slp->ns_nam, struct sockaddr_in *)->sin_addr.s_addr;
451 			nsd->nsd_authlen = nd->nd_authlen;
452 			(void) copyout(nd->nd_authstr, nsd->nsd_authstr,
453 				 nd->nd_authlen);
454 			(void) copyout((caddr_t)nsd, argp, sizeof (*nsd));
455 			return (ENEEDAUTH);
456 		}
457 		if (so->so_proto->pr_flags & PR_CONNREQUIRED)
458 			solockp = &slp->ns_solock;
459 		else
460 			solockp = (int *)0;
461 		nd->nd_repstat = 0;
462 		/*
463 		 * nam == nam2 for connectionless protocols such as UDP
464 		 * nam2 == NULL for connection based protocols to disable
465 		 *    recent request caching.
466 		 */
467 		nam2 = nd->nd_nam;
468 
469 		if (nam2) {
470 			nam = nam2;
471 			cacherep = nfsrv_getcache(nam2, nd, &mreq);
472 		} else {
473 			nam = slp->ns_nam;
474 			cacherep = RC_DOIT;
475 		}
476 
477 		/*
478 		 * Check for just starting up for NQNFS and send
479 		 * fake "try again later" replies to the NQNFS clients.
480 		 */
481 		if (notstarted && nqnfsstarttime <= time.tv_sec) {
482 			if (modify_flag) {
483 				nqnfsstarttime = time.tv_sec + nqsrv_writeslack;
484 				modify_flag = 0;
485 			} else
486 				notstarted = 0;
487 		}
488 		if (notstarted) {
489 			if (nd->nd_nqlflag == NQL_NOVAL)
490 				cacherep = RC_DROPIT;
491 			else if (nd->nd_procnum != NFSPROC_WRITE) {
492 				nd->nd_procnum = NFSPROC_NOOP;
493 				nd->nd_repstat = NQNFS_TRYLATER;
494 				cacherep = RC_DOIT;
495 			} else
496 				modify_flag = 1;
497 		} else if (nd->nd_flag & NFSD_AUTHFAIL) {
498 			nd->nd_flag &= ~NFSD_AUTHFAIL;
499 			nd->nd_procnum = NFSPROC_NOOP;
500 			nd->nd_repstat = NQNFS_AUTHERR;
501 			cacherep = RC_DOIT;
502 		}
503 
504 		switch (cacherep) {
505 		case RC_DOIT:
506 			error = (*(nfsrv_procs[nd->nd_procnum]))(nd,
507 				nd->nd_mrep, nd->nd_md, nd->nd_dpos, &nd->nd_cr,
508 				nam, &mreq);
509 			if (error) {
510 				if (nd->nd_procnum != NQNFSPROC_VACATED)
511 					nfsstats.srv_errs++;
512 				if (nam2) {
513 					nfsrv_updatecache(nam2, nd, FALSE, mreq);
514 					m_freem(nam2);
515 				}
516 				break;
517 			}
518 			nfsstats.srvrpccnt[nd->nd_procnum]++;
519 			if (nam2)
520 				nfsrv_updatecache(nam2, nd, TRUE, mreq);
521 			nd->nd_mrep = (struct mbuf *)0;
522 		case RC_REPLY:
523 			m = mreq;
524 			siz = 0;
525 			while (m) {
526 				siz += m->m_len;
527 				m = m->m_next;
528 			}
529 			if (siz <= 0 || siz > NFS_MAXPACKET) {
530 				printf("mbuf siz=%d\n",siz);
531 				panic("Bad nfs svc reply");
532 			}
533 			m = mreq;
534 			m->m_pkthdr.len = siz;
535 			m->m_pkthdr.rcvif = (struct ifnet *)0;
536 			/*
537 			 * For stream protocols, prepend a Sun RPC
538 			 * Record Mark.
539 			 */
540 			if (sotype == SOCK_STREAM) {
541 				M_PREPEND(m, NFSX_UNSIGNED, M_WAIT);
542 				*mtod(m, u_long *) = htonl(0x80000000 | siz);
543 			}
544 			if (solockp)
545 				(void) nfs_sndlock(solockp, (struct nfsreq *)0);
546 			if (nd->nd_sref == slp->ns_sref)
547 			    error = nfs_send(so, nam2, m, (struct nfsreq *)0);
548 			else {
549 			    error = EPIPE;
550 			    m_freem(m);
551 			}
552 			if (nam2)
553 				MFREE(nam2, m);
554 			if (nd->nd_mrep)
555 				m_freem(nd->nd_mrep);
556 			if (error == EPIPE)
557 				nfsrv_zapsock(slp, p);
558 			if (solockp)
559 				nfs_sndunlock(solockp);
560 			if (error == EINTR || error == ERESTART)
561 				goto done;
562 			break;
563 		case RC_DROPIT:
564 			m_freem(nd->nd_mrep);
565 			m_freem(nam2);
566 			break;
567 		};
568 		nd->nd_flag &= ~NFSD_REQINPROG;
569 		nd->nd_slp = (struct nfssvc_sock *)0;
570 	}
571 done:
572 	s = splnet();
573 	remque(nd);
574 	splx(s);
575 	free((caddr_t)nd, M_NFSD);
576 	nsd->nsd_nfsd = (struct nfsd *)0;
577 	if (--nfs_numnfsd == 0) {
578 		slp = nfssvc_sockhead.ns_next;
579 		while (slp != &nfssvc_sockhead) {
580 			if (slp->ns_flag & SLP_VALID)
581 				nfsrv_zapsock(slp, p);
582 			slp = slp->ns_next;
583 		}
584 		nfsrv_cleancache();	/* And clear out server cache */
585 	}
586 	return (error);
587 }
588 
589 /*
590  * Asynchronous I/O daemons for client nfs.
591  * These babies just pretend to be disk interrupt service routines.
592  * They are mainly here for read ahead/write behind.
593  * Never returns unless it fails or gets killed.
594  */
595 nfssvc_iod(p)
596 	struct proc *p;
597 {
598 	register struct buf *bp, *dp;
599 	register int i, myiod;
600 	int error = 0;
601 
602 	/*
603 	 * Assign my position or return error if too many already running
604 	 */
605 	myiod = -1;
606 	for (i = 0; i < NFS_MAXASYNCDAEMON; i++)
607 		if (nfs_asyncdaemon[i] == 0) {
608 			nfs_asyncdaemon[i]++;
609 			myiod = i;
610 			break;
611 		}
612 	if (myiod == -1)
613 		return (EBUSY);
614 	nfs_numasync++;
615 	dp = &nfs_bqueue;
616 	/*
617 	 * Just loop around doin our stuff until SIGKILL
618 	 */
619 	for (;;) {
620 		while (dp->b_actf == NULL && error == 0) {
621 			nfs_iodwant[myiod] = p;
622 			error = tsleep((caddr_t)&nfs_iodwant[myiod],
623 				PWAIT | PCATCH, "nfsidl", 0);
624 			nfs_iodwant[myiod] = (struct proc *)0;
625 		}
626 		while (dp->b_actf != NULL) {
627 			/* Take one off the end of the list */
628 			bp = dp->b_actl;
629 			if (bp->b_actl == dp) {
630 				dp->b_actf = dp->b_actl = (struct buf *)0;
631 			} else {
632 				dp->b_actl = bp->b_actl;
633 				bp->b_actl->b_actf = dp;
634 			}
635 			(void) nfs_doio(bp, (struct proc *)0);
636 		}
637 		if (error) {
638 			nfs_asyncdaemon[myiod] = 0;
639 			nfs_numasync--;
640 			return (error);
641 		}
642 	}
643 }
644 
645 /*
646  * Shut down a socket associated with an nfssvc_sock structure.
647  * Should be called with the send lock set, if required.
648  * The trick here is to increment the sref at the start, so that the nfsds
649  * will stop using it and clear ns_flag at the end so that it will not be
650  * reassigned during cleanup.
651  */
652 nfsrv_zapsock(slp, p)
653 	register struct nfssvc_sock *slp;
654 	struct proc *p;
655 {
656 	register struct nfsuid *nuidp, *onuidp;
657 	register int i;
658 	struct socket *so;
659 	struct file *fp;
660 	struct mbuf *m;
661 
662 	if (fp = slp->ns_fp) {
663 		slp->ns_fp = (struct file *)0;
664 		slp->ns_sref++;
665 		so = slp->ns_so;
666 		soshutdown(so, 2);
667 		closef(fp, p);
668 		if (slp->ns_nam)
669 			MFREE(slp->ns_nam, m);
670 		m_freem(slp->ns_raw);
671 		m_freem(slp->ns_rec);
672 		nuidp = slp->ns_lrunext;
673 		while (nuidp != (struct nfsuid *)slp) {
674 			onuidp = nuidp;
675 			nuidp = nuidp->nu_lrunext;
676 			free((caddr_t)onuidp, M_NFSUID);
677 		}
678 		slp->ns_lrunext = slp->ns_lruprev = (struct nfsuid *)slp;
679 		for (i = 0; i < NUIDHASHSIZ; i++)
680 			slp->ns_uidh[i] = (struct nfsuid *)0;
681 		slp->ns_flag = 0;
682 	}
683 }
684 
685 /*
686  * Get an authorization string for the uid by having the mount_nfs sitting
687  * on this mount point porpous out of the kernel and do it.
688  */
689 nfs_getauth(nmp, rep, cred, auth_type, auth_str, auth_len)
690 	register struct nfsmount *nmp;
691 	struct nfsreq *rep;
692 	struct ucred *cred;
693 	int *auth_type;
694 	char **auth_str;
695 	int *auth_len;
696 {
697 	int error = 0;
698 
699 	while ((nmp->nm_flag & NFSMNT_WAITAUTH) == 0) {
700 		nmp->nm_flag |= NFSMNT_WANTAUTH;
701 		(void) tsleep((caddr_t)&nmp->nm_authtype, PSOCK,
702 			"nfsauth1", 2 * hz);
703 		if (error = nfs_sigintr(nmp, rep, rep->r_procp)) {
704 			nmp->nm_flag &= ~NFSMNT_WANTAUTH;
705 			return (error);
706 		}
707 	}
708 	nmp->nm_flag &= ~(NFSMNT_WAITAUTH | NFSMNT_WANTAUTH);
709 	nmp->nm_authstr = *auth_str = (char *)malloc(RPCAUTH_MAXSIZ, M_TEMP, M_WAITOK);
710 	nmp->nm_authuid = cred->cr_uid;
711 	wakeup((caddr_t)&nmp->nm_authstr);
712 
713 	/*
714 	 * And wait for mount_nfs to do its stuff.
715 	 */
716 	while ((nmp->nm_flag & NFSMNT_HASAUTH) == 0 && error == 0) {
717 		(void) tsleep((caddr_t)&nmp->nm_authlen, PSOCK,
718 			"nfsauth2", 2 * hz);
719 		error = nfs_sigintr(nmp, rep, rep->r_procp);
720 	}
721 	if (nmp->nm_flag & NFSMNT_AUTHERR) {
722 		nmp->nm_flag &= ~NFSMNT_AUTHERR;
723 		error = EAUTH;
724 	}
725 	if (error)
726 		free((caddr_t)*auth_str, M_TEMP);
727 	else {
728 		*auth_type = nmp->nm_authtype;
729 		*auth_len = nmp->nm_authlen;
730 	}
731 	nmp->nm_flag &= ~NFSMNT_HASAUTH;
732 	nmp->nm_flag |= NFSMNT_WAITAUTH;
733 	if (nmp->nm_flag & NFSMNT_WANTAUTH) {
734 		nmp->nm_flag &= ~NFSMNT_WANTAUTH;
735 		wakeup((caddr_t)&nmp->nm_authtype);
736 	}
737 	return (error);
738 }
739