sys/vfs/nfs/nfs_socket.c

   1 /*
   2  * Copyright (c) 1989, 1991, 1993, 1995
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * This code is derived from software contributed to Berkeley by
   6  * Rick Macklem at The University of Guelph.
   7  *
   8  * Redistribution and use in source and binary forms, with or without
   9  * modification, are permitted provided that the following conditions
  10  * are met:
  11  * 1. Redistributions of source code must retain the above copyright
  12  *    notice, this list of conditions and the following disclaimer.
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in the
  15  *    documentation and/or other materials provided with the distribution.
  16  * 3. All advertising materials mentioning features or use of this software
  17  *    must display the following acknowledgement:
  18  *      This product includes software developed by the University of
  19  *      California, Berkeley and its contributors.
  20  * 4. Neither the name of the University nor the names of its contributors
  21  *    may be used to endorse or promote products derived from this software
  22  *    without specific prior written permission.
  23  *
  24  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  34  * SUCH DAMAGE.
  35  *
  36  *      @(#)nfs_socket.c        8.5 (Berkeley) 3/30/95
  37  * $FreeBSD: src/sys/nfs/nfs_socket.c,v 1.60.2.6 2003/03/26 01:44:46 alfred Exp $
  38  * $DragonFly: src/sys/vfs/nfs/nfs_socket.c,v 1.17 2004/06/02 14:43:04 eirikn Exp $
  39  */
  40
  41 /*
  42  * Socket operations for use by nfs
  43  */
  44
  45 #include <sys/param.h>
  46 #include <sys/systm.h>
  47 #include <sys/proc.h>
  48 #include <sys/malloc.h>
  49 #include <sys/mount.h>
  50 #include <sys/kernel.h>
  51 #include <sys/mbuf.h>
  52 #include <sys/vnode.h>
  53 #include <sys/protosw.h>
  54 #include <sys/resourcevar.h>
  55 #include <sys/socket.h>
  56 #include <sys/socketvar.h>
  57 #include <sys/socketops.h>
  58 #include <sys/syslog.h>
  59 #include <sys/thread.h>
  60 #include <sys/tprintf.h>
  61 #include <sys/sysctl.h>
  62 #include <sys/signalvar.h>
  63
  64 #include <netinet/in.h>
  65 #include <netinet/tcp.h>
  66 #include <sys/thread2.h>
  67
  68 #include "rpcv2.h"
  69 #include "nfsproto.h"
  70 #include "nfs.h"
  71 #include "xdr_subs.h"
  72 #include "nfsm_subs.h"
  73 #include "nfsmount.h"
  74 #include "nfsnode.h"
  75 #include "nfsrtt.h"
  76 #include "nqnfs.h"
  77
  78 #define TRUE    1
  79 #define FALSE   0
  80
  81 /*
  82  * Estimate rto for an nfs rpc sent via. an unreliable datagram.
  83  * Use the mean and mean deviation of rtt for the appropriate type of rpc
  84  * for the frequent rpcs and a default for the others.
  85  * The justification for doing "other" this way is that these rpcs
  86  * happen so infrequently that timer est. would probably be stale.
  87  * Also, since many of these rpcs are
  88  * non-idempotent, a conservative timeout is desired.
  89  * getattr, lookup - A+2D
  90  * read, write     - A+4D
  91  * other           - nm_timeo
  92  */
  93 #define NFS_RTO(n, t) \
  94         ((t) == 0 ? (n)->nm_timeo : \
  95          ((t) < 3 ? \
  96           (((((n)->nm_srtt[t-1] + 3) >> 2) + (n)->nm_sdrtt[t-1] + 1) >> 1) : \
  97           ((((n)->nm_srtt[t-1] + 7) >> 3) + (n)->nm_sdrtt[t-1] + 1)))
  98 #define NFS_SRTT(r)     (r)->r_nmp->nm_srtt[proct[(r)->r_procnum] - 1]
  99 #define NFS_SDRTT(r)    (r)->r_nmp->nm_sdrtt[proct[(r)->r_procnum] - 1]
 100 /*
 101  * External data, mostly RPC constants in XDR form
 102  */
 103 extern u_int32_t rpc_reply, rpc_msgdenied, rpc_mismatch, rpc_vers,
 104         rpc_auth_unix, rpc_msgaccepted, rpc_call, rpc_autherr,
 105         rpc_auth_kerb;
 106 extern u_int32_t nfs_prog, nqnfs_prog;
 107 extern time_t nqnfsstarttime;
 108 extern struct nfsstats nfsstats;
 109 extern int nfsv3_procid[NFS_NPROCS];
 110 extern int nfs_ticks;
 111
 112 /*
 113  * Defines which timer to use for the procnum.
 114  * 0 - default
 115  * 1 - getattr
 116  * 2 - lookup
 117  * 3 - read
 118  * 4 - write
 119  */
 120 static int proct[NFS_NPROCS] = {
 121         0, 1, 0, 2, 1, 3, 3, 4, 0, 0, 0, 0, 0, 0, 0, 0, 3, 3, 0, 0, 0, 0, 0,
 122         0, 0, 0,
 123 };
 124
 125 static int nfs_realign_test;
 126 static int nfs_realign_count;
 127 static int nfs_bufpackets = 4;
 128
 129 SYSCTL_DECL(_vfs_nfs);
 130
 131 SYSCTL_INT(_vfs_nfs, OID_AUTO, realign_test, CTLFLAG_RW, &nfs_realign_test, 0, "");
 132 SYSCTL_INT(_vfs_nfs, OID_AUTO, realign_count, CTLFLAG_RW, &nfs_realign_count, 0, "");
 133 SYSCTL_INT(_vfs_nfs, OID_AUTO, bufpackets, CTLFLAG_RW, &nfs_bufpackets, 0, "");
 134
 135
 136 /*
 137  * There is a congestion window for outstanding rpcs maintained per mount
 138  * point. The cwnd size is adjusted in roughly the way that:
 139  * Van Jacobson, Congestion avoidance and Control, In "Proceedings of
 140  * SIGCOMM '88". ACM, August 1988.
 141  * describes for TCP. The cwnd size is chopped in half on a retransmit timeout
 142  * and incremented by 1/cwnd when each rpc reply is received and a full cwnd
 143  * of rpcs is in progress.
 144  * (The sent count and cwnd are scaled for integer arith.)
 145  * Variants of "slow start" were tried and were found to be too much of a
 146  * performance hit (ave. rtt 3 times larger),
 147  * I suspect due to the large rtt that nfs rpcs have.
 148  */
 149 #define NFS_CWNDSCALE   256
 150 #define NFS_MAXCWND     (NFS_CWNDSCALE * 32)
 151 static int nfs_backoff[8] = { 2, 4, 8, 16, 32, 64, 128, 256, };
 152 int nfsrtton = 0;
 153 struct nfsrtt nfsrtt;
 154 struct callout_handle   nfs_timer_handle;
 155
 156 static int      nfs_msg (struct thread *,char *,char *);
 157 static int      nfs_rcvlock (struct nfsreq *);
 158 static void     nfs_rcvunlock (struct nfsreq *);
 159 static void     nfs_realign (struct mbuf **pm, int hsiz);
 160 static int      nfs_receive (struct nfsreq *rep, struct sockaddr **aname,
 161                                  struct mbuf **mp);
 162 static void     nfs_softterm (struct nfsreq *rep);
 163 static int      nfs_reconnect (struct nfsreq *rep);
 164 #ifndef NFS_NOSERVER
 165 static int      nfsrv_getstream (struct nfssvc_sock *,int);
 166
 167 int (*nfsrv3_procs[NFS_NPROCS]) (struct nfsrv_descript *nd,
 168                                     struct nfssvc_sock *slp,
 169                                     struct thread *td,
 170                                     struct mbuf **mreqp) = {
 171         nfsrv_null,
 172         nfsrv_getattr,
 173         nfsrv_setattr,
 174         nfsrv_lookup,
 175         nfsrv3_access,
 176         nfsrv_readlink,
 177         nfsrv_read,
 178         nfsrv_write,
 179         nfsrv_create,
 180         nfsrv_mkdir,
 181         nfsrv_symlink,
 182         nfsrv_mknod,
 183         nfsrv_remove,
 184         nfsrv_rmdir,
 185         nfsrv_rename,
 186         nfsrv_link,
 187         nfsrv_readdir,
 188         nfsrv_readdirplus,
 189         nfsrv_statfs,
 190         nfsrv_fsinfo,
 191         nfsrv_pathconf,
 192         nfsrv_commit,
 193         nqnfsrv_getlease,
 194         nqnfsrv_vacated,
 195         nfsrv_noop,
 196         nfsrv_noop
 197 };
 198 #endif /* NFS_NOSERVER */
 199
 200 /*
 201  * Initialize sockets and congestion for a new NFS connection.
 202  * We do not free the sockaddr if error.
 203  */
 204 int
 205 nfs_connect(struct nfsmount *nmp, struct nfsreq *rep)
 206 {
 207         struct socket *so;
 208         int s, error, rcvreserve, sndreserve;
 209         int pktscale;
 210         struct sockaddr *saddr;
 211         struct sockaddr_in *sin;
 212         struct thread *td = &thread0; /* only used for socreate and sobind */
 213
 214         nmp->nm_so = (struct socket *)0;
 215         saddr = nmp->nm_nam;
 216         error = socreate(saddr->sa_family, &nmp->nm_so, nmp->nm_sotype,
 217                 nmp->nm_soproto, td);
 218         if (error)
 219                 goto bad;
 220         so = nmp->nm_so;
 221         nmp->nm_soflags = so->so_proto->pr_flags;
 222
 223         /*
 224          * Some servers require that the client port be a reserved port number.
 225          */
 226         if (saddr->sa_family == AF_INET && (nmp->nm_flag & NFSMNT_RESVPORT)) {
 227                 struct sockopt sopt;
 228                 int ip;
 229                 struct sockaddr_in ssin;
 230
 231                 bzero(&sopt, sizeof sopt);
 232                 ip = IP_PORTRANGE_LOW;
 233                 sopt.sopt_dir = SOPT_SET;
 234                 sopt.sopt_level = IPPROTO_IP;
 235                 sopt.sopt_name = IP_PORTRANGE;
 236                 sopt.sopt_val = (void *)&ip;
 237                 sopt.sopt_valsize = sizeof(ip);
 238                 sopt.sopt_td = NULL;
 239                 error = sosetopt(so, &sopt);
 240                 if (error)
 241                         goto bad;
 242                 bzero(&ssin, sizeof ssin);
 243                 sin = &ssin;
 244                 sin->sin_len = sizeof (struct sockaddr_in);
 245                 sin->sin_family = AF_INET;
 246                 sin->sin_addr.s_addr = INADDR_ANY;
 247                 sin->sin_port = htons(0);
 248                 error = sobind(so, (struct sockaddr *)sin, td);
 249                 if (error)
 250                         goto bad;
 251                 bzero(&sopt, sizeof sopt);
 252                 ip = IP_PORTRANGE_DEFAULT;
 253                 sopt.sopt_dir = SOPT_SET;
 254                 sopt.sopt_level = IPPROTO_IP;
 255                 sopt.sopt_name = IP_PORTRANGE;
 256                 sopt.sopt_val = (void *)&ip;
 257                 sopt.sopt_valsize = sizeof(ip);
 258                 sopt.sopt_td = NULL;
 259                 error = sosetopt(so, &sopt);
 260                 if (error)
 261                         goto bad;
 262         }
 263
 264         /*
 265          * Protocols that do not require connections may be optionally left
 266          * unconnected for servers that reply from a port other than NFS_PORT.
 267          */
 268         if (nmp->nm_flag & NFSMNT_NOCONN) {
 269                 if (nmp->nm_soflags & PR_CONNREQUIRED) {
 270                         error = ENOTCONN;
 271                         goto bad;
 272                 }
 273         } else {
 274                 error = soconnect(so, nmp->nm_nam, td);
 275                 if (error)
 276                         goto bad;
 277
 278                 /*
 279                  * Wait for the connection to complete. Cribbed from the
 280                  * connect system call but with the wait timing out so
 281                  * that interruptible mounts don't hang here for a long time.
 282                  */
 283                 s = splnet();
 284                 while ((so->so_state & SS_ISCONNECTING) && so->so_error == 0) {
 285                         (void) tsleep((caddr_t)&so->so_timeo, 0,
 286                                 "nfscon", 2 * hz);
 287                         if ((so->so_state & SS_ISCONNECTING) &&
 288                             so->so_error == 0 && rep &&
 289                             (error = nfs_sigintr(nmp, rep, rep->r_td)) != 0){
 290                                 so->so_state &= ~SS_ISCONNECTING;
 291                                 splx(s);
 292                                 goto bad;
 293                         }
 294                 }
 295                 if (so->so_error) {
 296                         error = so->so_error;
 297                         so->so_error = 0;
 298                         splx(s);
 299                         goto bad;
 300                 }
 301                 splx(s);
 302         }
 303         so->so_rcv.sb_timeo = (5 * hz);
 304         so->so_snd.sb_timeo = (5 * hz);
 305
 306         /*
 307          * Get buffer reservation size from sysctl, but impose reasonable
 308          * limits.
 309          */
 310         pktscale = nfs_bufpackets;
 311         if (pktscale < 2)
 312                 pktscale = 2;
 313         if (pktscale > 64)
 314                 pktscale = 64;
 315
 316         if (nmp->nm_sotype == SOCK_DGRAM) {
 317                 sndreserve = (nmp->nm_wsize + NFS_MAXPKTHDR) * pktscale;
 318                 rcvreserve = (max(nmp->nm_rsize, nmp->nm_readdirsize) +
 319                     NFS_MAXPKTHDR) * pktscale;
 320         } else if (nmp->nm_sotype == SOCK_SEQPACKET) {
 321                 sndreserve = (nmp->nm_wsize + NFS_MAXPKTHDR) * pktscale;
 322                 rcvreserve = (max(nmp->nm_rsize, nmp->nm_readdirsize) +
 323                     NFS_MAXPKTHDR) * pktscale;
 324         } else {
 325                 if (nmp->nm_sotype != SOCK_STREAM)
 326                         panic("nfscon sotype");
 327                 if (so->so_proto->pr_flags & PR_CONNREQUIRED) {
 328                         struct sockopt sopt;
 329                         int val;
 330
 331                         bzero(&sopt, sizeof sopt);
 332                         sopt.sopt_level = SOL_SOCKET;
 333                         sopt.sopt_name = SO_KEEPALIVE;
 334                         sopt.sopt_val = &val;
 335                         sopt.sopt_valsize = sizeof val;
 336                         val = 1;
 337                         sosetopt(so, &sopt);
 338                 }
 339                 if (so->so_proto->pr_protocol == IPPROTO_TCP) {
 340                         struct sockopt sopt;
 341                         int val;
 342
 343                         bzero(&sopt, sizeof sopt);
 344                         sopt.sopt_level = IPPROTO_TCP;
 345                         sopt.sopt_name = TCP_NODELAY;
 346                         sopt.sopt_val = &val;
 347                         sopt.sopt_valsize = sizeof val;
 348                         val = 1;
 349                         sosetopt(so, &sopt);
 350                 }
 351                 sndreserve = (nmp->nm_wsize + NFS_MAXPKTHDR +
 352                     sizeof (u_int32_t)) * pktscale;
 353                 rcvreserve = (nmp->nm_rsize + NFS_MAXPKTHDR +
 354                     sizeof (u_int32_t)) * pktscale;
 355         }
 356         error = soreserve(so, sndreserve, rcvreserve,
 357                           &td->td_proc->p_rlimit[RLIMIT_SBSIZE]);
 358         if (error)
 359                 goto bad;
 360         so->so_rcv.sb_flags |= SB_NOINTR;
 361         so->so_snd.sb_flags |= SB_NOINTR;
 362
 363         /* Initialize other non-zero congestion variables */
 364         nmp->nm_srtt[0] = nmp->nm_srtt[1] = nmp->nm_srtt[2] =
 365                 nmp->nm_srtt[3] = (NFS_TIMEO << 3);
 366         nmp->nm_sdrtt[0] = nmp->nm_sdrtt[1] = nmp->nm_sdrtt[2] =
 367                 nmp->nm_sdrtt[3] = 0;
 368         nmp->nm_cwnd = NFS_MAXCWND / 2;     /* Initial send window */
 369         nmp->nm_sent = 0;
 370         nmp->nm_timeouts = 0;
 371         return (0);
 372
 373 bad:
 374         nfs_disconnect(nmp);
 375         return (error);
 376 }
 377
 378 /*
 379  * Reconnect routine:
 380  * Called when a connection is broken on a reliable protocol.
 381  * - clean up the old socket
 382  * - nfs_connect() again
 383  * - set R_MUSTRESEND for all outstanding requests on mount point
 384  * If this fails the mount point is DEAD!
 385  * nb: Must be called with the nfs_sndlock() set on the mount point.
 386  */
 387 static int
 388 nfs_reconnect(struct nfsreq *rep)
 389 {
 390         struct nfsreq *rp;
 391         struct nfsmount *nmp = rep->r_nmp;
 392         int error;
 393
 394         nfs_disconnect(nmp);
 395         while ((error = nfs_connect(nmp, rep)) != 0) {
 396                 if (error == EINTR || error == ERESTART)
 397                         return (EINTR);
 398                 (void) tsleep((caddr_t)&lbolt, 0, "nfscon", 0);
 399         }
 400
 401         /*
 402          * Loop through outstanding request list and fix up all requests
 403          * on old socket.
 404          */
 405         for (rp = nfs_reqq.tqh_first; rp != 0; rp = rp->r_chain.tqe_next) {
 406                 if (rp->r_nmp == nmp)
 407                         rp->r_flags |= R_MUSTRESEND;
 408         }
 409         return (0);
 410 }
 411
 412 /*
 413  * NFS disconnect. Clean up and unlink.
 414  */
 415 void
 416 nfs_disconnect(struct nfsmount *nmp)
 417 {
 418         struct socket *so;
 419
 420         if (nmp->nm_so) {
 421                 so = nmp->nm_so;
 422                 nmp->nm_so = (struct socket *)0;
 423                 soshutdown(so, 2);
 424                 soclose(so);
 425         }
 426 }
 427
 428 void
 429 nfs_safedisconnect(struct nfsmount *nmp)
 430 {
 431         struct nfsreq dummyreq;
 432
 433         bzero(&dummyreq, sizeof(dummyreq));
 434         dummyreq.r_nmp = nmp;
 435         dummyreq.r_td = NULL;
 436         nfs_rcvlock(&dummyreq);
 437         nfs_disconnect(nmp);
 438         nfs_rcvunlock(&dummyreq);
 439 }
 440
 441 /*
 442  * This is the nfs send routine. For connection based socket types, it
 443  * must be called with an nfs_sndlock() on the socket.
 444  * "rep == NULL" indicates that it has been called from a server.
 445  * For the client side:
 446  * - return EINTR if the RPC is terminated, 0 otherwise
 447  * - set R_MUSTRESEND if the send fails for any reason
 448  * - do any cleanup required by recoverable socket errors (?)
 449  * For the server side:
 450  * - return EINTR or ERESTART if interrupted by a signal
 451  * - return EPIPE if a connection is lost for connection based sockets (TCP...)
 452  * - do any cleanup required by recoverable socket errors (?)
 453  */
 454 int
 455 nfs_send(struct socket *so, struct sockaddr *nam, struct mbuf *top,
 456          struct nfsreq *rep)
 457 {
 458         struct sockaddr *sendnam;
 459         int error, soflags, flags;
 460
 461         if (rep) {
 462                 if (rep->r_flags & R_SOFTTERM) {
 463                         m_freem(top);
 464                         return (EINTR);
 465                 }
 466                 if ((so = rep->r_nmp->nm_so) == NULL) {
 467                         rep->r_flags |= R_MUSTRESEND;
 468                         m_freem(top);
 469                         return (0);
 470                 }
 471                 rep->r_flags &= ~R_MUSTRESEND;
 472                 soflags = rep->r_nmp->nm_soflags;
 473         } else
 474                 soflags = so->so_proto->pr_flags;
 475         if ((soflags & PR_CONNREQUIRED) || (so->so_state & SS_ISCONNECTED))
 476                 sendnam = (struct sockaddr *)0;
 477         else
 478                 sendnam = nam;
 479         if (so->so_type == SOCK_SEQPACKET)
 480                 flags = MSG_EOR;
 481         else
 482                 flags = 0;
 483
 484         error = so_pru_sosend(so, sendnam, NULL, top, NULL, flags,
 485             curthread /*XXX*/);
 486         /*
 487          * ENOBUFS for dgram sockets is transient and non fatal.
 488          * No need to log, and no need to break a soft mount.
 489          */
 490         if (error == ENOBUFS && so->so_type == SOCK_DGRAM) {
 491                 error = 0;
 492                 if (rep)                /* do backoff retransmit on client */
 493                         rep->r_flags |= R_MUSTRESEND;
 494         }
 495
 496         if (error) {
 497                 if (rep) {
 498                         log(LOG_INFO, "nfs send error %d for server %s\n",error,
 499                             rep->r_nmp->nm_mountp->mnt_stat.f_mntfromname);
 500                         /*
 501                          * Deal with errors for the client side.
 502                          */
 503                         if (rep->r_flags & R_SOFTTERM)
 504                                 error = EINTR;
 505                         else
 506                                 rep->r_flags |= R_MUSTRESEND;
 507                 } else
 508                         log(LOG_INFO, "nfsd send error %d\n", error);
 509
 510                 /*
 511                  * Handle any recoverable (soft) socket errors here. (?)
 512                  */
 513                 if (error != EINTR && error != ERESTART &&
 514                         error != EWOULDBLOCK && error != EPIPE)
 515                         error = 0;
 516         }
 517         return (error);
 518 }
 519
 520 /*
 521  * Receive a Sun RPC Request/Reply. For SOCK_DGRAM, the work is all
 522  * done by soreceive(), but for SOCK_STREAM we must deal with the Record
 523  * Mark and consolidate the data into a new mbuf list.
 524  * nb: Sometimes TCP passes the data up to soreceive() in long lists of
 525  *     small mbufs.
 526  * For SOCK_STREAM we must be very careful to read an entire record once
 527  * we have read any of it, even if the system call has been interrupted.
 528  */
 529 static int
 530 nfs_receive(struct nfsreq *rep, struct sockaddr **aname, struct mbuf **mp)
 531 {
 532         struct socket *so;
 533         struct uio auio;
 534         struct iovec aio;
 535         struct mbuf *m;
 536         struct mbuf *control;
 537         u_int32_t len;
 538         struct sockaddr **getnam;
 539         int error, sotype, rcvflg;
 540         struct thread *td = curthread;  /* XXX */
 541
 542         /*
 543          * Set up arguments for soreceive()
 544          */
 545         *mp = (struct mbuf *)0;
 546         *aname = (struct sockaddr *)0;
 547         sotype = rep->r_nmp->nm_sotype;
 548
 549         /*
 550          * For reliable protocols, lock against other senders/receivers
 551          * in case a reconnect is necessary.
 552          * For SOCK_STREAM, first get the Record Mark to find out how much
 553          * more there is to get.
 554          * We must lock the socket against other receivers
 555          * until we have an entire rpc request/reply.
 556          */
 557         if (sotype != SOCK_DGRAM) {
 558                 error = nfs_sndlock(rep);
 559                 if (error)
 560                         return (error);
 561 tryagain:
 562                 /*
 563                  * Check for fatal errors and resending request.
 564                  */
 565                 /*
 566                  * Ugh: If a reconnect attempt just happened, nm_so
 567                  * would have changed. NULL indicates a failed
 568                  * attempt that has essentially shut down this
 569                  * mount point.
 570                  */
 571                 if (rep->r_mrep || (rep->r_flags & R_SOFTTERM)) {
 572                         nfs_sndunlock(rep);
 573                         return (EINTR);
 574                 }
 575                 so = rep->r_nmp->nm_so;
 576                 if (!so) {
 577                         error = nfs_reconnect(rep);
 578                         if (error) {
 579                                 nfs_sndunlock(rep);
 580                                 return (error);
 581                         }
 582                         goto tryagain;
 583                 }
 584                 while (rep->r_flags & R_MUSTRESEND) {
 585                         m = m_copym(rep->r_mreq, 0, M_COPYALL, MB_WAIT);
 586                         nfsstats.rpcretries++;
 587                         error = nfs_send(so, rep->r_nmp->nm_nam, m, rep);
 588                         if (error) {
 589                                 if (error == EINTR || error == ERESTART ||
 590                                     (error = nfs_reconnect(rep)) != 0) {
 591                                         nfs_sndunlock(rep);
 592                                         return (error);
 593                                 }
 594                                 goto tryagain;
 595                         }
 596                 }
 597                 nfs_sndunlock(rep);
 598                 if (sotype == SOCK_STREAM) {
 599                         aio.iov_base = (caddr_t) &len;
 600                         aio.iov_len = sizeof(u_int32_t);
 601                         auio.uio_iov = &aio;
 602                         auio.uio_iovcnt = 1;
 603                         auio.uio_segflg = UIO_SYSSPACE;
 604                         auio.uio_rw = UIO_READ;
 605                         auio.uio_offset = 0;
 606                         auio.uio_resid = sizeof(u_int32_t);
 607                         auio.uio_td = td;
 608                         do {
 609                            rcvflg = MSG_WAITALL;
 610                            error = so_pru_soreceive(so, NULL, &auio, NULL,
 611                                NULL, &rcvflg);
 612                            if (error == EWOULDBLOCK && rep) {
 613                                 if (rep->r_flags & R_SOFTTERM)
 614                                         return (EINTR);
 615                            }
 616                         } while (error == EWOULDBLOCK);
 617                         if (!error && auio.uio_resid > 0) {
 618                             /*
 619                              * Don't log a 0 byte receive; it means
 620                              * that the socket has been closed, and
 621                              * can happen during normal operation
 622                              * (forcible unmount or Solaris server).
 623                              */
 624                             if (auio.uio_resid != sizeof (u_int32_t))
 625                             log(LOG_INFO,
 626                                  "short receive (%d/%d) from nfs server %s\n",
 627                                  (int)(sizeof(u_int32_t) - auio.uio_resid),
 628                                  (int)sizeof(u_int32_t),
 629                                  rep->r_nmp->nm_mountp->mnt_stat.f_mntfromname);
 630                             error = EPIPE;
 631                         }
 632                         if (error)
 633                                 goto errout;
 634                         len = ntohl(len) & ~0x80000000;
 635                         /*
 636                          * This is SERIOUS! We are out of sync with the sender
 637                          * and forcing a disconnect/reconnect is all I can do.
 638                          */
 639                         if (len > NFS_MAXPACKET) {
 640                             log(LOG_ERR, "%s (%d) from nfs server %s\n",
 641                                 "impossible packet length",
 642                                 len,
 643                                 rep->r_nmp->nm_mountp->mnt_stat.f_mntfromname);
 644                             error = EFBIG;
 645                             goto errout;
 646                         }
 647                         auio.uio_resid = len;
 648                         do {
 649                             rcvflg = MSG_WAITALL;
 650                             error =  so_pru_soreceive(so, NULL, &auio, mp,
 651                                 NULL, &rcvflg);
 652                         } while (error == EWOULDBLOCK || error == EINTR ||
 653                                  error == ERESTART);
 654                         if (!error && auio.uio_resid > 0) {
 655                             if (len != auio.uio_resid)
 656                             log(LOG_INFO,
 657                                 "short receive (%d/%d) from nfs server %s\n",
 658                                 len - auio.uio_resid, len,
 659                                 rep->r_nmp->nm_mountp->mnt_stat.f_mntfromname);
 660                             error = EPIPE;
 661                         }
 662                 } else {
 663                         /*
 664                          * NB: Since uio_resid is big, MSG_WAITALL is ignored
 665                          * and soreceive() will return when it has either a
 666                          * control msg or a data msg.
 667                          * We have no use for control msg., but must grab them
 668                          * and then throw them away so we know what is going
 669                          * on.
 670                          */
 671                         auio.uio_resid = len = 100000000; /* Anything Big */
 672                         auio.uio_td = td;
 673                         do {
 674                             rcvflg = 0;
 675                             error =  so_pru_soreceive(so, NULL, &auio, mp,
 676                                 &control, &rcvflg);
 677                             if (control)
 678                                 m_freem(control);
 679                             if (error == EWOULDBLOCK && rep) {
 680                                 if (rep->r_flags & R_SOFTTERM)
 681                                         return (EINTR);
 682                             }
 683                         } while (error == EWOULDBLOCK ||
 684                                  (!error && *mp == NULL && control));
 685                         if ((rcvflg & MSG_EOR) == 0)
 686                                 printf("Egad!!\n");
 687                         if (!error && *mp == NULL)
 688                                 error = EPIPE;
 689                         len -= auio.uio_resid;
 690                 }
 691 errout:
 692                 if (error && error != EINTR && error != ERESTART) {
 693                         m_freem(*mp);
 694                         *mp = (struct mbuf *)0;
 695                         if (error != EPIPE)
 696                                 log(LOG_INFO,
 697                                     "receive error %d from nfs server %s\n",
 698                                     error,
 699                                  rep->r_nmp->nm_mountp->mnt_stat.f_mntfromname);
 700                         error = nfs_sndlock(rep);
 701                         if (!error) {
 702                                 error = nfs_reconnect(rep);
 703                                 if (!error)
 704                                         goto tryagain;
 705                                 else
 706                                         nfs_sndunlock(rep);
 707                         }
 708                 }
 709         } else {
 710                 if ((so = rep->r_nmp->nm_so) == NULL)
 711                         return (EACCES);
 712                 if (so->so_state & SS_ISCONNECTED)
 713                         getnam = (struct sockaddr **)0;
 714                 else
 715                         getnam = aname;
 716                 auio.uio_resid = len = 1000000;
 717                 auio.uio_td = td;
 718                 do {
 719                         rcvflg = 0;
 720                         error =  so_pru_soreceive(so, getnam, &auio, mp, NULL,
 721                             &rcvflg);
 722                         if (error == EWOULDBLOCK &&
 723                             (rep->r_flags & R_SOFTTERM))
 724                                 return (EINTR);
 725                 } while (error == EWOULDBLOCK);
 726                 len -= auio.uio_resid;
 727         }
 728         if (error) {
 729                 m_freem(*mp);
 730                 *mp = (struct mbuf *)0;
 731         }
 732         /*
 733          * Search for any mbufs that are not a multiple of 4 bytes long
 734          * or with m_data not longword aligned.
 735          * These could cause pointer alignment problems, so copy them to
 736          * well aligned mbufs.
 737          */
 738         nfs_realign(mp, 5 * NFSX_UNSIGNED);
 739         return (error);
 740 }
 741
 742 /*
 743  * Implement receipt of reply on a socket.
 744  * We must search through the list of received datagrams matching them
 745  * with outstanding requests using the xid, until ours is found.
 746  */
 747 /* ARGSUSED */
 748 int
 749 nfs_reply(struct nfsreq *myrep)
 750 {
 751         struct nfsreq *rep;
 752         struct nfsmount *nmp = myrep->r_nmp;
 753         int32_t t1;
 754         struct mbuf *mrep, *md;
 755         struct sockaddr *nam;
 756         u_int32_t rxid, *tl;
 757         caddr_t dpos, cp2;
 758         int error;
 759
 760         /*
 761          * Loop around until we get our own reply
 762          */
 763         for (;;) {
 764                 /*
 765                  * Lock against other receivers so that I don't get stuck in
 766                  * sbwait() after someone else has received my reply for me.
 767                  * Also necessary for connection based protocols to avoid
 768                  * race conditions during a reconnect.
 769                  * If nfs_rcvlock() returns EALREADY, that means that
 770                  * the reply has already been recieved by another
 771                  * process and we can return immediately.  In this
 772                  * case, the lock is not taken to avoid races with
 773                  * other processes.
 774                  */
 775                 error = nfs_rcvlock(myrep);
 776                 if (error == EALREADY)
 777                         return (0);
 778                 if (error)
 779                         return (error);
 780                 /*
 781                  * Get the next Rpc reply off the socket
 782                  */
 783                 error = nfs_receive(myrep, &nam, &mrep);
 784                 nfs_rcvunlock(myrep);
 785                 if (error) {
 786
 787                         /*
 788                          * Ignore routing errors on connectionless protocols??
 789                          */
 790                         if (NFSIGNORE_SOERROR(nmp->nm_soflags, error)) {
 791                                 nmp->nm_so->so_error = 0;
 792                                 if (myrep->r_flags & R_GETONEREP)
 793                                         return (0);
 794                                 continue;
 795                         }
 796                         return (error);
 797                 }
 798                 if (nam)
 799                         FREE(nam, M_SONAME);
 800
 801                 /*
 802                  * Get the xid and check that it is an rpc reply
 803                  */
 804                 md = mrep;
 805                 dpos = mtod(md, caddr_t);
 806                 nfsm_dissect(tl, u_int32_t *, 2*NFSX_UNSIGNED);
 807                 rxid = *tl++;
 808                 if (*tl != rpc_reply) {
 809 #ifndef NFS_NOSERVER
 810                         if (nmp->nm_flag & NFSMNT_NQNFS) {
 811                                 if (nqnfs_callback(nmp, mrep, md, dpos))
 812                                         nfsstats.rpcinvalid++;
 813                         } else {
 814                                 nfsstats.rpcinvalid++;
 815                                 m_freem(mrep);
 816                         }
 817 #else
 818                         nfsstats.rpcinvalid++;
 819                         m_freem(mrep);
 820 #endif
 821 nfsmout:
 822                         if (myrep->r_flags & R_GETONEREP)
 823                                 return (0);
 824                         continue;
 825                 }
 826
 827                 /*
 828                  * Loop through the request list to match up the reply
 829                  * Iff no match, just drop the datagram
 830                  */
 831                 for (rep = nfs_reqq.tqh_first; rep != 0;
 832                     rep = rep->r_chain.tqe_next) {
 833                         if (rep->r_mrep == NULL && rxid == rep->r_xid) {
 834                                 /* Found it.. */
 835                                 rep->r_mrep = mrep;
 836                                 rep->r_md = md;
 837                                 rep->r_dpos = dpos;
 838                                 if (nfsrtton) {
 839                                         struct rttl *rt;
 840
 841                                         rt = &nfsrtt.rttl[nfsrtt.pos];
 842                                         rt->proc = rep->r_procnum;
 843                                         rt->rto = NFS_RTO(nmp, proct[rep->r_procnum]);
 844                                         rt->sent = nmp->nm_sent;
 845                                         rt->cwnd = nmp->nm_cwnd;
 846                                         rt->srtt = nmp->nm_srtt[proct[rep->r_procnum] - 1];
 847                                         rt->sdrtt = nmp->nm_sdrtt[proct[rep->r_procnum] - 1];
 848                                         rt->fsid = nmp->nm_mountp->mnt_stat.f_fsid;
 849                                         getmicrotime(&rt->tstamp);
 850                                         if (rep->r_flags & R_TIMING)
 851                                                 rt->rtt = rep->r_rtt;
 852                                         else
 853                                                 rt->rtt = 1000000;
 854                                         nfsrtt.pos = (nfsrtt.pos + 1) % NFSRTTLOGSIZ;
 855                                 }
 856                                 /*
 857                                  * Update congestion window.
 858                                  * Do the additive increase of
 859                                  * one rpc/rtt.
 860                                  */
 861                                 if (nmp->nm_cwnd <= nmp->nm_sent) {
 862                                         nmp->nm_cwnd +=
 863                                            (NFS_CWNDSCALE * NFS_CWNDSCALE +
 864                                            (nmp->nm_cwnd >> 1)) / nmp->nm_cwnd;
 865                                         if (nmp->nm_cwnd > NFS_MAXCWND)
 866                                                 nmp->nm_cwnd = NFS_MAXCWND;
 867                                 }
 868                                 crit_enter();   /* nfs_timer interlock*/
 869                                 if (rep->r_flags & R_SENT) {
 870                                         rep->r_flags &= ~R_SENT;
 871                                         nmp->nm_sent -= NFS_CWNDSCALE;
 872                                 }
 873                                 crit_exit();
 874                                 /*
 875                                  * Update rtt using a gain of 0.125 on the mean
 876                                  * and a gain of 0.25 on the deviation.
 877                                  */
 878                                 if (rep->r_flags & R_TIMING) {
 879                                         /*
 880                                          * Since the timer resolution of
 881                                          * NFS_HZ is so course, it can often
 882                                          * result in r_rtt == 0. Since
 883                                          * r_rtt == N means that the actual
 884                                          * rtt is between N+dt and N+2-dt ticks,
 885                                          * add 1.
 886                                          */
 887                                         t1 = rep->r_rtt + 1;
 888                                         t1 -= (NFS_SRTT(rep) >> 3);
 889                                         NFS_SRTT(rep) += t1;
 890                                         if (t1 < 0)
 891                                                 t1 = -t1;
 892                                         t1 -= (NFS_SDRTT(rep) >> 2);
 893                                         NFS_SDRTT(rep) += t1;
 894                                 }
 895                                 nmp->nm_timeouts = 0;
 896                                 break;
 897                         }
 898                 }
 899                 /*
 900                  * If not matched to a request, drop it.
 901                  * If it's mine, get out.
 902                  */
 903                 if (rep == 0) {
 904                         nfsstats.rpcunexpected++;
 905                         m_freem(mrep);
 906                 } else if (rep == myrep) {
 907                         if (rep->r_mrep == NULL)
 908                                 panic("nfsreply nil");
 909                         return (0);
 910                 }
 911                 if (myrep->r_flags & R_GETONEREP)
 912                         return (0);
 913         }
 914 }
 915
 916 /*
 917  * nfs_request - goes something like this
 918  *      - fill in request struct
 919  *      - links it into list
 920  *      - calls nfs_send() for first transmit
 921  *      - calls nfs_receive() to get reply
 922  *      - break down rpc header and return with nfs reply pointed to
 923  *        by mrep or error
 924  * nb: always frees up mreq mbuf list
 925  */
 926 int
 927 nfs_request(struct vnode *vp, struct mbuf *mrest, int procnum,
 928             struct thread *td, struct ucred *cred, struct mbuf **mrp,
 929             struct mbuf **mdp, caddr_t *dposp)
 930 {
 931         struct mbuf *mrep, *m2;
 932         struct nfsreq *rep;
 933         u_int32_t *tl;
 934         int i;
 935         struct nfsmount *nmp;
 936         struct mbuf *m, *md, *mheadend;
 937         struct nfsnode *np;
 938         char nickv[RPCX_NICKVERF];
 939         time_t reqtime, waituntil;
 940         caddr_t dpos, cp2;
 941         int t1, nqlflag, cachable, s, error = 0, mrest_len, auth_len, auth_type;
 942         int trylater_delay = NQ_TRYLATERDEL, trylater_cnt = 0, failed_auth = 0;
 943         int verf_len, verf_type;
 944         u_int32_t xid;
 945         u_quad_t frev;
 946         char *auth_str, *verf_str;
 947         NFSKERBKEY_T key;               /* save session key */
 948
 949         /* Reject requests while attempting a forced unmount. */
 950         if (vp->v_mount->mnt_kern_flag & MNTK_UNMOUNTF) {
 951                 m_freem(mrest);
 952                 return (ESTALE);
 953         }
 954         nmp = VFSTONFS(vp->v_mount);
 955         MALLOC(rep, struct nfsreq *, sizeof(struct nfsreq), M_NFSREQ, M_WAITOK);
 956         rep->r_nmp = nmp;
 957         rep->r_vp = vp;
 958         rep->r_td = td;
 959         rep->r_procnum = procnum;
 960         i = 0;
 961         m = mrest;
 962         while (m) {
 963                 i += m->m_len;
 964                 m = m->m_next;
 965         }
 966         mrest_len = i;
 967
 968         /*
 969          * Get the RPC header with authorization.
 970          */
 971 kerbauth:
 972         verf_str = auth_str = (char *)0;
 973         if (nmp->nm_flag & NFSMNT_KERB) {
 974                 verf_str = nickv;
 975                 verf_len = sizeof (nickv);
 976                 auth_type = RPCAUTH_KERB4;
 977                 bzero((caddr_t)key, sizeof (key));
 978                 if (failed_auth || nfs_getnickauth(nmp, cred, &auth_str,
 979                         &auth_len, verf_str, verf_len)) {
 980                         error = nfs_getauth(nmp, rep, cred, &auth_str,
 981                                 &auth_len, verf_str, &verf_len, key);
 982                         if (error) {
 983                                 free((caddr_t)rep, M_NFSREQ);
 984                                 m_freem(mrest);
 985                                 return (error);
 986                         }
 987                 }
 988         } else {
 989                 auth_type = RPCAUTH_UNIX;
 990                 if (cred->cr_ngroups < 1)
 991                         panic("nfsreq nogrps");
 992                 auth_len = ((((cred->cr_ngroups - 1) > nmp->nm_numgrps) ?
 993                         nmp->nm_numgrps : (cred->cr_ngroups - 1)) << 2) +
 994                         5 * NFSX_UNSIGNED;
 995         }
 996         m = nfsm_rpchead(cred, nmp->nm_flag, procnum, auth_type, auth_len,
 997              auth_str, verf_len, verf_str, mrest, mrest_len, &mheadend, &xid);
 998         if (auth_str)
 999                 free(auth_str, M_TEMP);
1000
1001         /*
1002          * For stream protocols, insert a Sun RPC Record Mark.
1003          */
1004         if (nmp->nm_sotype == SOCK_STREAM) {
1005                 M_PREPEND(m, NFSX_UNSIGNED, MB_WAIT);
1006                 if (m == NULL)
1007                         return (ENOBUFS);
1008                 *mtod(m, u_int32_t *) = htonl(0x80000000 |
1009                          (m->m_pkthdr.len - NFSX_UNSIGNED));
1010         }
1011         rep->r_mreq = m;
1012         rep->r_xid = xid;
1013 tryagain:
1014         if (nmp->nm_flag & NFSMNT_SOFT)
1015                 rep->r_retry = nmp->nm_retry;
1016         else
1017                 rep->r_retry = NFS_MAXREXMIT + 1;       /* past clip limit */
1018         rep->r_rtt = rep->r_rexmit = 0;
1019         if (proct[procnum] > 0)
1020                 rep->r_flags = R_TIMING | R_MASKTIMER;
1021         else
1022                 rep->r_flags = R_MASKTIMER;
1023         rep->r_mrep = NULL;
1024
1025         /*
1026          * Do the client side RPC.
1027          */
1028         nfsstats.rpcrequests++;
1029
1030         /*
1031          * Chain request into list of outstanding requests. Be sure
1032          * to put it LAST so timer finds oldest requests first.  Note
1033          * that R_MASKTIMER is set at the moment to prevent any timer
1034          * action on this request while we are still doing processing on
1035          * it below.  splsoftclock() primarily protects nm_sent.  Note
1036          * that we may block in this code so there is no atomicy guarentee.
1037          */
1038         s = splsoftclock();
1039         TAILQ_INSERT_TAIL(&nfs_reqq, rep, r_chain);
1040
1041         /* Get send time for nqnfs */
1042         reqtime = time_second;
1043
1044         /*
1045          * If backing off another request or avoiding congestion, don't
1046          * send this one now but let timer do it. If not timing a request,
1047          * do it now.
1048          */
1049         if (nmp->nm_so && (nmp->nm_sotype != SOCK_DGRAM ||
1050                 (nmp->nm_flag & NFSMNT_DUMBTIMR) ||
1051                 nmp->nm_sent < nmp->nm_cwnd)) {
1052                 if (nmp->nm_soflags & PR_CONNREQUIRED)
1053                         error = nfs_sndlock(rep);
1054                 if (!error) {
1055                         m2 = m_copym(m, 0, M_COPYALL, MB_WAIT);
1056                         error = nfs_send(nmp->nm_so, nmp->nm_nam, m2, rep);
1057                         if (nmp->nm_soflags & PR_CONNREQUIRED)
1058                                 nfs_sndunlock(rep);
1059                 }
1060                 if (!error && (rep->r_flags & R_MUSTRESEND) == 0) {
1061                         nmp->nm_sent += NFS_CWNDSCALE;
1062                         rep->r_flags |= R_SENT;
1063                 }
1064         } else {
1065                 rep->r_rtt = -1;
1066         }
1067
1068         /*
1069          * Let the timer do what it will with the request, then
1070          * wait for the reply from our send or the timer's.
1071          */
1072         rep->r_flags &= ~R_MASKTIMER;
1073         splx(s);
1074         if (!error || error == EPIPE)
1075                 error = nfs_reply(rep);
1076
1077         /*
1078          * RPC done, unlink the request.
1079          */
1080         s = splsoftclock();
1081         TAILQ_REMOVE(&nfs_reqq, rep, r_chain);
1082
1083         /*
1084          * Decrement the outstanding request count.
1085          */
1086         if (rep->r_flags & R_SENT) {
1087                 rep->r_flags &= ~R_SENT;
1088                 nmp->nm_sent -= NFS_CWNDSCALE;
1089         }
1090         splx(s);
1091
1092         /*
1093          * If there was a successful reply and a tprintf msg.
1094          * tprintf a response.
1095          */
1096         if (!error && (rep->r_flags & R_TPRINTFMSG))
1097                 nfs_msg(rep->r_td, nmp->nm_mountp->mnt_stat.f_mntfromname,
1098                     "is alive again");
1099         mrep = rep->r_mrep;
1100         md = rep->r_md;
1101         dpos = rep->r_dpos;
1102         if (error) {
1103                 m_freem(rep->r_mreq);
1104                 free((caddr_t)rep, M_NFSREQ);
1105                 return (error);
1106         }
1107
1108         /*
1109          * break down the rpc header and check if ok
1110          */
1111         nfsm_dissect(tl, u_int32_t *, 3 * NFSX_UNSIGNED);
1112         if (*tl++ == rpc_msgdenied) {
1113                 if (*tl == rpc_mismatch)
1114                         error = EOPNOTSUPP;
1115                 else if ((nmp->nm_flag & NFSMNT_KERB) && *tl++ == rpc_autherr) {
1116                         if (!failed_auth) {
1117                                 failed_auth++;
1118                                 mheadend->m_next = (struct mbuf *)0;
1119                                 m_freem(mrep);
1120                                 m_freem(rep->r_mreq);
1121                                 goto kerbauth;
1122                         } else
1123                                 error = EAUTH;
1124                 } else
1125                         error = EACCES;
1126                 m_freem(mrep);
1127                 m_freem(rep->r_mreq);
1128                 free((caddr_t)rep, M_NFSREQ);
1129                 return (error);
1130         }
1131
1132         /*
1133          * Grab any Kerberos verifier, otherwise just throw it away.
1134          */
1135         verf_type = fxdr_unsigned(int, *tl++);
1136         i = fxdr_unsigned(int32_t, *tl);
1137         if ((nmp->nm_flag & NFSMNT_KERB) && verf_type == RPCAUTH_KERB4) {
1138                 error = nfs_savenickauth(nmp, cred, i, key, &md, &dpos, mrep);
1139                 if (error)
1140                         goto nfsmout;
1141         } else if (i > 0)
1142                 nfsm_adv(nfsm_rndup(i));
1143         nfsm_dissect(tl, u_int32_t *, NFSX_UNSIGNED);
1144         /* 0 == ok */
1145         if (*tl == 0) {
1146                 nfsm_dissect(tl, u_int32_t *, NFSX_UNSIGNED);
1147                 if (*tl != 0) {
1148                         error = fxdr_unsigned(int, *tl);
1149                         if ((nmp->nm_flag & NFSMNT_NFSV3) &&
1150                                 error == NFSERR_TRYLATER) {
1151                                 m_freem(mrep);
1152                                 error = 0;
1153                                 waituntil = time_second + trylater_delay;
1154                                 while (time_second < waituntil)
1155                                         (void) tsleep((caddr_t)&lbolt,
1156                                                 0, "nqnfstry", 0);
1157                                 trylater_delay *= nfs_backoff[trylater_cnt];
1158                                 if (trylater_cnt < 7)
1159                                         trylater_cnt++;
1160                                 goto tryagain;
1161                         }
1162
1163                         /*
1164                          * If the File Handle was stale, invalidate the
1165                          * lookup cache, just in case.
1166                          */
1167                         if (error == ESTALE)
1168                                 cache_purge(vp);
1169                         if (nmp->nm_flag & NFSMNT_NFSV3) {
1170                                 *mrp = mrep;
1171                                 *mdp = md;
1172                                 *dposp = dpos;
1173                                 error |= NFSERR_RETERR;
1174                         } else
1175                                 m_freem(mrep);
1176                         m_freem(rep->r_mreq);
1177                         free((caddr_t)rep, M_NFSREQ);
1178                         return (error);
1179                 }
1180
1181                 /*
1182                  * For nqnfs, get any lease in reply
1183                  */
1184                 if (nmp->nm_flag & NFSMNT_NQNFS) {
1185                         nfsm_dissect(tl, u_int32_t *, NFSX_UNSIGNED);
1186                         if (*tl) {
1187                                 np = VTONFS(vp);
1188                                 nqlflag = fxdr_unsigned(int, *tl);
1189                                 nfsm_dissect(tl, u_int32_t *, 4*NFSX_UNSIGNED);
1190                                 cachable = fxdr_unsigned(int, *tl++);
1191                                 reqtime += fxdr_unsigned(int, *tl++);
1192                                 if (reqtime > time_second) {
1193                                     frev = fxdr_hyper(tl);
1194                                     nqnfs_clientlease(nmp, np, nqlflag,
1195                                         cachable, reqtime, frev);
1196                                 }
1197                         }
1198                 }
1199                 *mrp = mrep;
1200                 *mdp = md;
1201                 *dposp = dpos;
1202                 m_freem(rep->r_mreq);
1203                 FREE((caddr_t)rep, M_NFSREQ);
1204                 return (0);
1205         }
1206         m_freem(mrep);
1207         error = EPROTONOSUPPORT;
1208 nfsmout:
1209         m_freem(rep->r_mreq);
1210         free((caddr_t)rep, M_NFSREQ);
1211         return (error);
1212 }
1213
1214 #ifndef NFS_NOSERVER
1215 /*
1216  * Generate the rpc reply header
1217  * siz arg. is used to decide if adding a cluster is worthwhile
1218  */
1219 int
1220 nfs_rephead(int siz, struct nfsrv_descript *nd, struct nfssvc_sock *slp,
1221             int err, int cache, u_quad_t *frev, struct mbuf **mrq,
1222             struct mbuf **mbp, caddr_t *bposp)
1223 {
1224         u_int32_t *tl;
1225         struct mbuf *mreq;
1226         caddr_t bpos;
1227         struct mbuf *mb, *mb2;
1228
1229         MGETHDR(mreq, MB_WAIT, MT_DATA);
1230         mb = mreq;
1231         /*
1232          * If this is a big reply, use a cluster else
1233          * try and leave leading space for the lower level headers.
1234          */
1235         siz += RPC_REPLYSIZ;
1236         if ((max_hdr + siz) >= MINCLSIZE) {
1237                 MCLGET(mreq, MB_WAIT);
1238         } else
1239                 mreq->m_data += max_hdr;
1240         tl = mtod(mreq, u_int32_t *);
1241         mreq->m_len = 6 * NFSX_UNSIGNED;
1242         bpos = ((caddr_t)tl) + mreq->m_len;
1243         *tl++ = txdr_unsigned(nd->nd_retxid);
1244         *tl++ = rpc_reply;
1245         if (err == ERPCMISMATCH || (err & NFSERR_AUTHERR)) {
1246                 *tl++ = rpc_msgdenied;
1247                 if (err & NFSERR_AUTHERR) {
1248                         *tl++ = rpc_autherr;
1249                         *tl = txdr_unsigned(err & ~NFSERR_AUTHERR);
1250                         mreq->m_len -= NFSX_UNSIGNED;
1251                         bpos -= NFSX_UNSIGNED;
1252                 } else {
1253                         *tl++ = rpc_mismatch;
1254                         *tl++ = txdr_unsigned(RPC_VER2);
1255                         *tl = txdr_unsigned(RPC_VER2);
1256                 }
1257         } else {
1258                 *tl++ = rpc_msgaccepted;
1259
1260                 /*
1261                  * For Kerberos authentication, we must send the nickname
1262                  * verifier back, otherwise just RPCAUTH_NULL.
1263                  */
1264                 if (nd->nd_flag & ND_KERBFULL) {
1265                     struct nfsuid *nuidp;
1266                     struct timeval ktvin, ktvout;
1267
1268                     for (nuidp = NUIDHASH(slp, nd->nd_cr.cr_uid)->lh_first;
1269                         nuidp != 0; nuidp = nuidp->nu_hash.le_next) {
1270                         if (nuidp->nu_cr.cr_uid == nd->nd_cr.cr_uid &&
1271                             (!nd->nd_nam2 || netaddr_match(NU_NETFAM(nuidp),
1272                              &nuidp->nu_haddr, nd->nd_nam2)))
1273                             break;
1274                     }
1275                     if (nuidp) {
1276                         ktvin.tv_sec =
1277                             txdr_unsigned(nuidp->nu_timestamp.tv_sec - 1);
1278                         ktvin.tv_usec =
1279                             txdr_unsigned(nuidp->nu_timestamp.tv_usec);
1280
1281                         /*
1282                          * Encrypt the timestamp in ecb mode using the
1283                          * session key.
1284                          */
1285 #ifdef NFSKERB
1286                         XXX
1287 #endif
1288
1289                         *tl++ = rpc_auth_kerb;
1290                         *tl++ = txdr_unsigned(3 * NFSX_UNSIGNED);
1291                         *tl = ktvout.tv_sec;
1292                         nfsm_build(tl, u_int32_t *, 3 * NFSX_UNSIGNED);
1293                         *tl++ = ktvout.tv_usec;
1294                         *tl++ = txdr_unsigned(nuidp->nu_cr.cr_uid);
1295                     } else {
1296                         *tl++ = 0;
1297                         *tl++ = 0;
1298                     }
1299                 } else {
1300                         *tl++ = 0;
1301                         *tl++ = 0;
1302                 }
1303                 switch (err) {
1304                 case EPROGUNAVAIL:
1305                         *tl = txdr_unsigned(RPC_PROGUNAVAIL);
1306                         break;
1307                 case EPROGMISMATCH:
1308                         *tl = txdr_unsigned(RPC_PROGMISMATCH);
1309                         nfsm_build(tl, u_int32_t *, 2 * NFSX_UNSIGNED);
1310                         if (nd->nd_flag & ND_NQNFS) {
1311                                 *tl++ = txdr_unsigned(3);
1312                                 *tl = txdr_unsigned(3);
1313                         } else {
1314                                 *tl++ = txdr_unsigned(2);
1315                                 *tl = txdr_unsigned(3);
1316                         }
1317                         break;
1318                 case EPROCUNAVAIL:
1319                         *tl = txdr_unsigned(RPC_PROCUNAVAIL);
1320                         break;
1321                 case EBADRPC:
1322                         *tl = txdr_unsigned(RPC_GARBAGE);
1323                         break;
1324                 default:
1325                         *tl = 0;
1326                         if (err != NFSERR_RETVOID) {
1327                                 nfsm_build(tl, u_int32_t *, NFSX_UNSIGNED);
1328                                 if (err)
1329                                     *tl = txdr_unsigned(nfsrv_errmap(nd, err));
1330                                 else
1331                                     *tl = 0;
1332                         }
1333                         break;
1334                 };
1335         }
1336
1337         /*
1338          * For nqnfs, piggyback lease as requested.
1339          */
1340         if ((nd->nd_flag & ND_NQNFS) && err == 0) {
1341                 if (nd->nd_flag & ND_LEASE) {
1342                         nfsm_build(tl, u_int32_t *, 5 * NFSX_UNSIGNED);
1343                         *tl++ = txdr_unsigned(nd->nd_flag & ND_LEASE);
1344                         *tl++ = txdr_unsigned(cache);
1345                         *tl++ = txdr_unsigned(nd->nd_duration);
1346                         txdr_hyper(*frev, tl);
1347                 } else {
1348                         nfsm_build(tl, u_int32_t *, NFSX_UNSIGNED);
1349                         *tl = 0;
1350                 }
1351         }
1352         if (mrq != NULL)
1353             *mrq = mreq;
1354         *mbp = mb;
1355         *bposp = bpos;
1356         if (err != 0 && err != NFSERR_RETVOID)
1357                 nfsstats.srvrpc_errs++;
1358         return (0);
1359 }
1360
1361
1362 #endif /* NFS_NOSERVER */
1363 /*
1364  * Nfs timer routine
1365  * Scan the nfsreq list and retranmit any requests that have timed out
1366  * To avoid retransmission attempts on STREAM sockets (in the future) make
1367  * sure to set the r_retry field to 0 (implies nm_retry == 0).
1368  */
1369 void
1370 nfs_timer(void *arg /* never used */)
1371 {
1372         struct nfsreq *rep;
1373         struct mbuf *m;
1374         struct socket *so;
1375         struct nfsmount *nmp;
1376         int timeo;
1377         int s, error;
1378 #ifndef NFS_NOSERVER
1379         static long lasttime = 0;
1380         struct nfssvc_sock *slp;
1381         u_quad_t cur_usec;
1382 #endif /* NFS_NOSERVER */
1383         struct thread *td = &thread0; /* XXX for credentials, will break if sleep */
1384
1385         s = splnet();
1386         for (rep = nfs_reqq.tqh_first; rep != 0; rep = rep->r_chain.tqe_next) {
1387                 nmp = rep->r_nmp;
1388                 if (rep->r_mrep || (rep->r_flags & (R_SOFTTERM|R_MASKTIMER)))
1389                         continue;
1390                 if (nfs_sigintr(nmp, rep, rep->r_td)) {
1391                         nfs_softterm(rep);
1392                         continue;
1393                 }
1394                 if (rep->r_rtt >= 0) {
1395                         rep->r_rtt++;
1396                         if (nmp->nm_flag & NFSMNT_DUMBTIMR)
1397                                 timeo = nmp->nm_timeo;
1398                         else
1399                                 timeo = NFS_RTO(nmp, proct[rep->r_procnum]);
1400                         if (nmp->nm_timeouts > 0)
1401                                 timeo *= nfs_backoff[nmp->nm_timeouts - 1];
1402                         if (rep->r_rtt <= timeo)
1403                                 continue;
1404                         if (nmp->nm_timeouts < 8)
1405                                 nmp->nm_timeouts++;
1406                 }
1407                 /*
1408                  * Check for server not responding
1409                  */
1410                 if ((rep->r_flags & R_TPRINTFMSG) == 0 &&
1411                      rep->r_rexmit > nmp->nm_deadthresh) {
1412                         nfs_msg(rep->r_td,
1413                             nmp->nm_mountp->mnt_stat.f_mntfromname,
1414                             "not responding");
1415                         rep->r_flags |= R_TPRINTFMSG;
1416                 }
1417                 if (rep->r_rexmit >= rep->r_retry) {    /* too many */
1418                         nfsstats.rpctimeouts++;
1419                         nfs_softterm(rep);
1420                         continue;
1421                 }
1422                 if (nmp->nm_sotype != SOCK_DGRAM) {
1423                         if (++rep->r_rexmit > NFS_MAXREXMIT)
1424                                 rep->r_rexmit = NFS_MAXREXMIT;
1425                         continue;
1426                 }
1427                 if ((so = nmp->nm_so) == NULL)
1428                         continue;
1429
1430                 /*
1431                  * If there is enough space and the window allows..
1432                  *      Resend it
1433                  * Set r_rtt to -1 in case we fail to send it now.
1434                  */
1435                 rep->r_rtt = -1;
1436                 if (sbspace(&so->so_snd) >= rep->r_mreq->m_pkthdr.len &&
1437                    ((nmp->nm_flag & NFSMNT_DUMBTIMR) ||
1438                     (rep->r_flags & R_SENT) ||
1439                     nmp->nm_sent < nmp->nm_cwnd) &&
1440                    (m = m_copym(rep->r_mreq, 0, M_COPYALL, MB_DONTWAIT))){
1441                         if ((nmp->nm_flag & NFSMNT_NOCONN) == 0)
1442                             error = so_pru_send(so, 0, m, (struct sockaddr *)0,
1443                                      (struct mbuf *)0, td);
1444                         else
1445                             error = so_pru_send(so, 0, m, nmp->nm_nam,
1446                                 (struct mbuf *)0, td);
1447                         if (error) {
1448                                 if (NFSIGNORE_SOERROR(nmp->nm_soflags, error))
1449                                         so->so_error = 0;
1450                         } else {
1451                                 /*
1452                                  * Iff first send, start timing
1453                                  * else turn timing off, backoff timer
1454                                  * and divide congestion window by 2.
1455                                  */
1456                                 if (rep->r_flags & R_SENT) {
1457                                         rep->r_flags &= ~R_TIMING;
1458                                         if (++rep->r_rexmit > NFS_MAXREXMIT)
1459                                                 rep->r_rexmit = NFS_MAXREXMIT;
1460                                         nmp->nm_cwnd >>= 1;
1461                                         if (nmp->nm_cwnd < NFS_CWNDSCALE)
1462                                                 nmp->nm_cwnd = NFS_CWNDSCALE;
1463                                         nfsstats.rpcretries++;
1464                                 } else {
1465                                         rep->r_flags |= R_SENT;
1466                                         nmp->nm_sent += NFS_CWNDSCALE;
1467                                 }
1468                                 rep->r_rtt = 0;
1469                         }
1470                 }
1471         }
1472 #ifndef NFS_NOSERVER
1473         /*
1474          * Call the nqnfs server timer once a second to handle leases.
1475          */
1476         if (lasttime != time_second) {
1477                 lasttime = time_second;
1478                 nqnfs_serverd();
1479         }
1480
1481         /*
1482          * Scan the write gathering queues for writes that need to be
1483          * completed now.
1484          */
1485         cur_usec = nfs_curusec();
1486         for (slp = nfssvc_sockhead.tqh_first; slp != 0;
1487             slp = slp->ns_chain.tqe_next) {
1488             if (slp->ns_tq.lh_first && slp->ns_tq.lh_first->nd_time<=cur_usec)
1489                 nfsrv_wakenfsd(slp);
1490         }
1491 #endif /* NFS_NOSERVER */
1492         splx(s);
1493         nfs_timer_handle = timeout(nfs_timer, (void *)0, nfs_ticks);
1494 }
1495
1496 /*
1497  * Mark all of an nfs mount's outstanding requests with R_SOFTTERM and
1498  * wait for all requests to complete. This is used by forced unmounts
1499  * to terminate any outstanding RPCs.
1500  */
1501 int
1502 nfs_nmcancelreqs(struct nfsmount *nmp)
1503 {
1504         struct nfsreq *req;
1505         int i, s1, s2;
1506
1507         s1 = splnet();
1508         s2 = splsoftclock();
1509         TAILQ_FOREACH(req, &nfs_reqq, r_chain) {
1510                 if (nmp != req->r_nmp || req->r_mrep != NULL ||
1511                     (req->r_flags & R_SOFTTERM))
1512                         continue;
1513                 nfs_softterm(req);
1514         }
1515         splx(s2);
1516         splx(s1);
1517
1518         for (i = 0; i < 30; i++) {
1519                 int s = splnet();
1520                 TAILQ_FOREACH(req, &nfs_reqq, r_chain) {
1521                         if (nmp == req->r_nmp)
1522                                 break;
1523                 }
1524                 splx(s);
1525                 if (req == NULL)
1526                         return (0);
1527                 tsleep(&lbolt, 0, "nfscancel", 0);
1528         }
1529         return (EBUSY);
1530 }
1531
1532 /*
1533  * Flag a request as being about to terminate (due to NFSMNT_INT/NFSMNT_SOFT).
1534  * The nm_send count is decremented now to avoid deadlocks when the process in
1535  * soreceive() hasn't yet managed to send its own request.
1536  *
1537  * This routine must be called at splsoftclock() to protect r_flags and
1538  * nm_sent.
1539  */
1540
1541 static void
1542 nfs_softterm(struct nfsreq *rep)
1543 {
1544         rep->r_flags |= R_SOFTTERM;
1545
1546         if (rep->r_flags & R_SENT) {
1547                 rep->r_nmp->nm_sent -= NFS_CWNDSCALE;
1548                 rep->r_flags &= ~R_SENT;
1549         }
1550 }
1551
1552 /*
1553  * Test for a termination condition pending on the process.
1554  * This is used for NFSMNT_INT mounts.
1555  */
1556 int
1557 nfs_sigintr(struct nfsmount *nmp, struct nfsreq *rep, struct thread *td)
1558 {
1559         sigset_t tmpset;
1560         struct proc *p;
1561
1562         if (rep && (rep->r_flags & R_SOFTTERM))
1563                 return (EINTR);
1564         /* Terminate all requests while attempting a forced unmount. */
1565         if (nmp->nm_mountp->mnt_kern_flag & MNTK_UNMOUNTF)
1566                 return (EINTR);
1567         if (!(nmp->nm_flag & NFSMNT_INT))
1568                 return (0);
1569         /* td might be NULL YYY */
1570         if (td == NULL || (p = td->td_proc) == NULL)
1571                 return (0);
1572
1573         tmpset = p->p_siglist;
1574         SIGSETNAND(tmpset, p->p_sigmask);
1575         SIGSETNAND(tmpset, p->p_sigignore);
1576         if (SIGNOTEMPTY(p->p_siglist) && NFSINT_SIGMASK(tmpset))
1577                 return (EINTR);
1578
1579         return (0);
1580 }
1581
1582 /*
1583  * Lock a socket against others.
1584  * Necessary for STREAM sockets to ensure you get an entire rpc request/reply
1585  * and also to avoid race conditions between the processes with nfs requests
1586  * in progress when a reconnect is necessary.
1587  */
1588 int
1589 nfs_sndlock(struct nfsreq *rep)
1590 {
1591         int *statep = &rep->r_nmp->nm_state;
1592         struct thread *td;
1593         int slptimeo;
1594         int slpflag;
1595         int error;
1596
1597         slpflag = 0;
1598         slptimeo = 0;
1599         td = rep->r_td;
1600         if (rep->r_nmp->nm_flag & NFSMNT_INT)
1601                 slpflag = PCATCH;
1602
1603         error = 0;
1604         crit_enter();
1605         while (*statep & NFSSTA_SNDLOCK) {
1606                 *statep |= NFSSTA_WANTSND;
1607                 if (nfs_sigintr(rep->r_nmp, rep, td)) {
1608                         error = EINTR;
1609                         break;
1610                 }
1611                 tsleep((caddr_t)statep, slpflag, "nfsndlck", slptimeo);
1612                 if (slpflag == PCATCH) {
1613                         slpflag = 0;
1614                         slptimeo = 2 * hz;
1615                 }
1616         }
1617         /* Always fail if our request has been cancelled. */
1618         if ((rep->r_flags & R_SOFTTERM))
1619                 error = EINTR;
1620         if (error == 0)
1621                 *statep |= NFSSTA_SNDLOCK;
1622         crit_exit();
1623         return (error);
1624 }
1625
1626 /*
1627  * Unlock the stream socket for others.
1628  */
1629 void
1630 nfs_sndunlock(struct nfsreq *rep)
1631 {
1632         int *statep = &rep->r_nmp->nm_state;
1633
1634         if ((*statep & NFSSTA_SNDLOCK) == 0)
1635                 panic("nfs sndunlock");
1636         crit_enter();
1637         *statep &= ~NFSSTA_SNDLOCK;
1638         if (*statep & NFSSTA_WANTSND) {
1639                 *statep &= ~NFSSTA_WANTSND;
1640                 wakeup((caddr_t)statep);
1641         }
1642         crit_exit();
1643 }
1644
1645 static int
1646 nfs_rcvlock(struct nfsreq *rep)
1647 {
1648         int *statep = &rep->r_nmp->nm_state;
1649         int slpflag;
1650         int slptimeo;
1651         int error;
1652
1653         /*
1654          * Unconditionally check for completion in case another nfsiod
1655          * get the packet while the caller was blocked, before the caller
1656          * called us.  Packet reception is handled by mainline code which
1657          * is protected by the BGL at the moment.
1658          *
1659          * We do not strictly need the second check just before the
1660          * tsleep(), but it's good defensive programming.
1661          */
1662         if (rep->r_mrep != NULL)
1663                 return (EALREADY);
1664
1665         if (rep->r_nmp->nm_flag & NFSMNT_INT)
1666                 slpflag = PCATCH;
1667         else
1668                 slpflag = 0;
1669         slptimeo = 0;
1670         error = 0;
1671         crit_enter();
1672         while (*statep & NFSSTA_RCVLOCK) {
1673                 if (nfs_sigintr(rep->r_nmp, rep, rep->r_td)) {
1674                         error = EINTR;
1675                         break;
1676                 }
1677                 if (rep->r_mrep != NULL) {
1678                         error = EALREADY;
1679                         break;
1680                 }
1681                 *statep |= NFSSTA_WANTRCV;
1682                 tsleep((caddr_t)statep, slpflag, "nfsrcvlk", slptimeo);
1683                 /*
1684                  * If our reply was recieved while we were sleeping,
1685                  * then just return without taking the lock to avoid a
1686                  * situation where a single iod could 'capture' the
1687                  * recieve lock.
1688                  */
1689                 if (rep->r_mrep != NULL) {
1690                         error = EALREADY;
1691                         break;
1692                 }
1693                 if (slpflag == PCATCH) {
1694                         slpflag = 0;
1695                         slptimeo = 2 * hz;
1696                 }
1697         }
1698         if (error == 0) {
1699                 *statep |= NFSSTA_RCVLOCK;
1700                 rep->r_nmp->nm_rcvlock_td = curthread;  /* DEBUGGING */
1701         }
1702         crit_exit();
1703         return (error);
1704 }
1705
1706 /*
1707  * Unlock the stream socket for others.
1708  */
1709 static void
1710 nfs_rcvunlock(struct nfsreq *rep)
1711 {
1712         int *statep = &rep->r_nmp->nm_state;
1713
1714         if ((*statep & NFSSTA_RCVLOCK) == 0)
1715                 panic("nfs rcvunlock");
1716         crit_enter();
1717         rep->r_nmp->nm_rcvlock_td = (void *)-1; /* DEBUGGING */
1718         *statep &= ~NFSSTA_RCVLOCK;
1719         if (*statep & NFSSTA_WANTRCV) {
1720                 *statep &= ~NFSSTA_WANTRCV;
1721                 wakeup((caddr_t)statep);
1722         }
1723         crit_exit();
1724 }
1725
1726 /*
1727  *      nfs_realign:
1728  *
1729  *      Check for badly aligned mbuf data and realign by copying the unaligned
1730  *      portion of the data into a new mbuf chain and freeing the portions
1731  *      of the old chain that were replaced.
1732  *
1733  *      We cannot simply realign the data within the existing mbuf chain
1734  *      because the underlying buffers may contain other rpc commands and
1735  *      we cannot afford to overwrite them.
1736  *
1737  *      We would prefer to avoid this situation entirely.  The situation does
1738  *      not occur with NFS/UDP and is supposed to only occassionally occur
1739  *      with TCP.  Use vfs.nfs.realign_count and realign_test to check this.
1740  */
1741 static void
1742 nfs_realign(struct mbuf **pm, int hsiz)
1743 {
1744         struct mbuf *m;
1745         struct mbuf *n = NULL;
1746         int off = 0;
1747
1748         ++nfs_realign_test;
1749
1750         while ((m = *pm) != NULL) {
1751                 if ((m->m_len & 0x3) || (mtod(m, intptr_t) & 0x3)) {
1752                         MGET(n, MB_WAIT, MT_DATA);
1753                         if (m->m_len >= MINCLSIZE) {
1754                                 MCLGET(n, MB_WAIT);
1755                         }
1756                         n->m_len = 0;
1757                         break;
1758                 }
1759                 pm = &m->m_next;
1760         }
1761
1762         /*
1763          * If n is non-NULL, loop on m copying data, then replace the
1764          * portion of the chain that had to be realigned.
1765          */
1766         if (n != NULL) {
1767                 ++nfs_realign_count;
1768                 while (m) {
1769                         m_copyback(n, off, m->m_len, mtod(m, caddr_t));
1770                         off += m->m_len;
1771                         m = m->m_next;
1772                 }
1773                 m_freem(*pm);
1774                 *pm = n;
1775         }
1776 }
1777
1778 #ifndef NFS_NOSERVER
1779
1780 /*
1781  * Parse an RPC request
1782  * - verify it
1783  * - fill in the cred struct.
1784  */
1785 int
1786 nfs_getreq(struct nfsrv_descript *nd, struct nfsd *nfsd, int has_header)
1787 {
1788         int len, i;
1789         u_int32_t *tl;
1790         int32_t t1;
1791         struct uio uio;
1792         struct iovec iov;
1793         caddr_t dpos, cp2, cp;
1794         u_int32_t nfsvers, auth_type;
1795         uid_t nickuid;
1796         int error = 0, nqnfs = 0, ticklen;
1797         struct mbuf *mrep, *md;
1798         struct nfsuid *nuidp;
1799         struct timeval tvin, tvout;
1800 #if 0                           /* until encrypted keys are implemented */
1801         NFSKERBKEYSCHED_T keys; /* stores key schedule */
1802 #endif
1803
1804         mrep = nd->nd_mrep;
1805         md = nd->nd_md;
1806         dpos = nd->nd_dpos;
1807         if (has_header) {
1808                 nfsm_dissect(tl, u_int32_t *, 10 * NFSX_UNSIGNED);
1809                 nd->nd_retxid = fxdr_unsigned(u_int32_t, *tl++);
1810                 if (*tl++ != rpc_call) {
1811                         m_freem(mrep);
1812                         return (EBADRPC);
1813                 }
1814         } else
1815                 nfsm_dissect(tl, u_int32_t *, 8 * NFSX_UNSIGNED);
1816         nd->nd_repstat = 0;
1817         nd->nd_flag = 0;
1818         if (*tl++ != rpc_vers) {
1819                 nd->nd_repstat = ERPCMISMATCH;
1820                 nd->nd_procnum = NFSPROC_NOOP;
1821                 return (0);
1822         }
1823         if (*tl != nfs_prog) {
1824                 if (*tl == nqnfs_prog)
1825                         nqnfs++;
1826                 else {
1827                         nd->nd_repstat = EPROGUNAVAIL;
1828                         nd->nd_procnum = NFSPROC_NOOP;
1829                         return (0);
1830                 }
1831         }
1832         tl++;
1833         nfsvers = fxdr_unsigned(u_int32_t, *tl++);
1834         if (((nfsvers < NFS_VER2 || nfsvers > NFS_VER3) && !nqnfs) ||
1835                 (nfsvers != NQNFS_VER3 && nqnfs)) {
1836                 nd->nd_repstat = EPROGMISMATCH;
1837                 nd->nd_procnum = NFSPROC_NOOP;
1838                 return (0);
1839         }
1840         if (nqnfs)
1841                 nd->nd_flag = (ND_NFSV3 | ND_NQNFS);
1842         else if (nfsvers == NFS_VER3)
1843                 nd->nd_flag = ND_NFSV3;
1844         nd->nd_procnum = fxdr_unsigned(u_int32_t, *tl++);
1845         if (nd->nd_procnum == NFSPROC_NULL)
1846                 return (0);
1847         if (nd->nd_procnum >= NFS_NPROCS ||
1848                 (!nqnfs && nd->nd_procnum >= NQNFSPROC_GETLEASE) ||
1849                 (!nd->nd_flag && nd->nd_procnum > NFSV2PROC_STATFS)) {
1850                 nd->nd_repstat = EPROCUNAVAIL;
1851                 nd->nd_procnum = NFSPROC_NOOP;
1852                 return (0);
1853         }
1854         if ((nd->nd_flag & ND_NFSV3) == 0)
1855                 nd->nd_procnum = nfsv3_procid[nd->nd_procnum];
1856         auth_type = *tl++;
1857         len = fxdr_unsigned(int, *tl++);
1858         if (len < 0 || len > RPCAUTH_MAXSIZ) {
1859                 m_freem(mrep);
1860                 return (EBADRPC);
1861         }
1862
1863         nd->nd_flag &= ~ND_KERBAUTH;
1864         /*
1865          * Handle auth_unix or auth_kerb.
1866          */
1867         if (auth_type == rpc_auth_unix) {
1868                 len = fxdr_unsigned(int, *++tl);
1869                 if (len < 0 || len > NFS_MAXNAMLEN) {
1870                         m_freem(mrep);
1871                         return (EBADRPC);
1872                 }
1873                 nfsm_adv(nfsm_rndup(len));
1874                 nfsm_dissect(tl, u_int32_t *, 3 * NFSX_UNSIGNED);
1875                 bzero((caddr_t)&nd->nd_cr, sizeof (struct ucred));
1876                 nd->nd_cr.cr_ref = 1;
1877                 nd->nd_cr.cr_uid = fxdr_unsigned(uid_t, *tl++);
1878                 nd->nd_cr.cr_gid = fxdr_unsigned(gid_t, *tl++);
1879                 len = fxdr_unsigned(int, *tl);
1880                 if (len < 0 || len > RPCAUTH_UNIXGIDS) {
1881                         m_freem(mrep);
1882                         return (EBADRPC);
1883                 }
1884                 nfsm_dissect(tl, u_int32_t *, (len + 2) * NFSX_UNSIGNED);
1885                 for (i = 1; i <= len; i++)
1886                     if (i < NGROUPS)
1887                         nd->nd_cr.cr_groups[i] = fxdr_unsigned(gid_t, *tl++);
1888                     else
1889                         tl++;
1890                 nd->nd_cr.cr_ngroups = (len >= NGROUPS) ? NGROUPS : (len + 1);
1891                 if (nd->nd_cr.cr_ngroups > 1)
1892                     nfsrvw_sort(nd->nd_cr.cr_groups, nd->nd_cr.cr_ngroups);
1893                 len = fxdr_unsigned(int, *++tl);
1894                 if (len < 0 || len > RPCAUTH_MAXSIZ) {
1895                         m_freem(mrep);
1896                         return (EBADRPC);
1897                 }
1898                 if (len > 0)
1899                         nfsm_adv(nfsm_rndup(len));
1900         } else if (auth_type == rpc_auth_kerb) {
1901                 switch (fxdr_unsigned(int, *tl++)) {
1902                 case RPCAKN_FULLNAME:
1903                         ticklen = fxdr_unsigned(int, *tl);
1904                         *((u_int32_t *)nfsd->nfsd_authstr) = *tl;
1905                         uio.uio_resid = nfsm_rndup(ticklen) + NFSX_UNSIGNED;
1906                         nfsd->nfsd_authlen = uio.uio_resid + NFSX_UNSIGNED;
1907                         if (uio.uio_resid > (len - 2 * NFSX_UNSIGNED)) {
1908                                 m_freem(mrep);
1909                                 return (EBADRPC);
1910                         }
1911                         uio.uio_offset = 0;
1912                         uio.uio_iov = &iov;
1913                         uio.uio_iovcnt = 1;
1914                         uio.uio_segflg = UIO_SYSSPACE;
1915                         iov.iov_base = (caddr_t)&nfsd->nfsd_authstr[4];
1916                         iov.iov_len = RPCAUTH_MAXSIZ - 4;
1917                         nfsm_mtouio(&uio, uio.uio_resid);
1918                         nfsm_dissect(tl, u_int32_t *, 2 * NFSX_UNSIGNED);
1919                         if (*tl++ != rpc_auth_kerb ||
1920                                 fxdr_unsigned(int, *tl) != 4 * NFSX_UNSIGNED) {
1921                                 printf("Bad kerb verifier\n");
1922                                 nd->nd_repstat = (NFSERR_AUTHERR|AUTH_BADVERF);
1923                                 nd->nd_procnum = NFSPROC_NOOP;
1924                                 return (0);
1925                         }
1926                         nfsm_dissect(cp, caddr_t, 4 * NFSX_UNSIGNED);
1927                         tl = (u_int32_t *)cp;
1928                         if (fxdr_unsigned(int, *tl) != RPCAKN_FULLNAME) {
1929                                 printf("Not fullname kerb verifier\n");
1930                                 nd->nd_repstat = (NFSERR_AUTHERR|AUTH_BADVERF);
1931                                 nd->nd_procnum = NFSPROC_NOOP;
1932                                 return (0);
1933                         }
1934                         cp += NFSX_UNSIGNED;
1935                         bcopy(cp, nfsd->nfsd_verfstr, 3 * NFSX_UNSIGNED);
1936                         nfsd->nfsd_verflen = 3 * NFSX_UNSIGNED;
1937                         nd->nd_flag |= ND_KERBFULL;
1938                         nfsd->nfsd_flag |= NFSD_NEEDAUTH;
1939                         break;
1940                 case RPCAKN_NICKNAME:
1941                         if (len != 2 * NFSX_UNSIGNED) {
1942                                 printf("Kerb nickname short\n");
1943                                 nd->nd_repstat = (NFSERR_AUTHERR|AUTH_BADCRED);
1944                                 nd->nd_procnum = NFSPROC_NOOP;
1945                                 return (0);
1946                         }
1947                         nickuid = fxdr_unsigned(uid_t, *tl);
1948                         nfsm_dissect(tl, u_int32_t *, 2 * NFSX_UNSIGNED);
1949                         if (*tl++ != rpc_auth_kerb ||
1950                                 fxdr_unsigned(int, *tl) != 3 * NFSX_UNSIGNED) {
1951                                 printf("Kerb nick verifier bad\n");
1952                                 nd->nd_repstat = (NFSERR_AUTHERR|AUTH_BADVERF);
1953                                 nd->nd_procnum = NFSPROC_NOOP;
1954                                 return (0);
1955                         }
1956                         nfsm_dissect(tl, u_int32_t *, 3 * NFSX_UNSIGNED);
1957                         tvin.tv_sec = *tl++;
1958                         tvin.tv_usec = *tl;
1959
1960                         for (nuidp = NUIDHASH(nfsd->nfsd_slp,nickuid)->lh_first;
1961                             nuidp != 0; nuidp = nuidp->nu_hash.le_next) {
1962                                 if (nuidp->nu_cr.cr_uid == nickuid &&
1963                                     (!nd->nd_nam2 ||
1964                                      netaddr_match(NU_NETFAM(nuidp),
1965                                       &nuidp->nu_haddr, nd->nd_nam2)))
1966                                         break;
1967                         }
1968                         if (!nuidp) {
1969                                 nd->nd_repstat =
1970                                         (NFSERR_AUTHERR|AUTH_REJECTCRED);
1971                                 nd->nd_procnum = NFSPROC_NOOP;
1972                                 return (0);
1973                         }
1974
1975                         /*
1976                          * Now, decrypt the timestamp using the session key
1977                          * and validate it.
1978                          */
1979 #ifdef NFSKERB
1980                         XXX
1981 #endif
1982
1983                         tvout.tv_sec = fxdr_unsigned(long, tvout.tv_sec);
1984                         tvout.tv_usec = fxdr_unsigned(long, tvout.tv_usec);
1985                         if (nuidp->nu_expire < time_second ||
1986                             nuidp->nu_timestamp.tv_sec > tvout.tv_sec ||
1987                             (nuidp->nu_timestamp.tv_sec == tvout.tv_sec &&
1988                              nuidp->nu_timestamp.tv_usec > tvout.tv_usec)) {
1989                                 nuidp->nu_expire = 0;
1990                                 nd->nd_repstat =
1991                                     (NFSERR_AUTHERR|AUTH_REJECTVERF);
1992                                 nd->nd_procnum = NFSPROC_NOOP;
1993                                 return (0);
1994                         }
1995                         nfsrv_setcred(&nuidp->nu_cr, &nd->nd_cr);
1996                         nd->nd_flag |= ND_KERBNICK;
1997                 };
1998         } else {
1999                 nd->nd_repstat = (NFSERR_AUTHERR | AUTH_REJECTCRED);
2000                 nd->nd_procnum = NFSPROC_NOOP;
2001                 return (0);
2002         }
2003
2004         /*
2005          * For nqnfs, get piggybacked lease request.
2006          */
2007         if (nqnfs && nd->nd_procnum != NQNFSPROC_EVICTED) {
2008                 nfsm_dissect(tl, u_int32_t *, NFSX_UNSIGNED);
2009                 nd->nd_flag |= fxdr_unsigned(int, *tl);
2010                 if (nd->nd_flag & ND_LEASE) {
2011                         nfsm_dissect(tl, u_int32_t *, NFSX_UNSIGNED);
2012                         nd->nd_duration = fxdr_unsigned(int32_t, *tl);
2013                 } else
2014                         nd->nd_duration = NQ_MINLEASE;
2015         } else
2016                 nd->nd_duration = NQ_MINLEASE;
2017         nd->nd_md = md;
2018         nd->nd_dpos = dpos;
2019         return (0);
2020 nfsmout:
2021         return (error);
2022 }
2023
2024 #endif
2025
2026 /*
2027  * Send a message to the originating process's terminal.  The thread and/or
2028  * process may be NULL.  YYY the thread should not be NULL but there may
2029  * still be some uio_td's that are still being passed as NULL through to
2030  * nfsm_request().
2031  */
2032 static int
2033 nfs_msg(struct thread *td, char *server, char *msg)
2034 {
2035         tpr_t tpr;
2036
2037         if (td && td->td_proc)
2038                 tpr = tprintf_open(td->td_proc);
2039         else
2040                 tpr = NULL;
2041         tprintf(tpr, "nfs server %s: %s\n", server, msg);
2042         tprintf_close(tpr);
2043         return (0);
2044 }
2045
2046 #ifndef NFS_NOSERVER
2047 /*
2048  * Socket upcall routine for the nfsd sockets.
2049  * The caddr_t arg is a pointer to the "struct nfssvc_sock".
2050  * Essentially do as much as possible non-blocking, else punt and it will
2051  * be called with MB_WAIT from an nfsd.
2052  */
2053 void
2054 nfsrv_rcv(struct socket *so, void *arg, int waitflag)
2055 {
2056         struct nfssvc_sock *slp = (struct nfssvc_sock *)arg;
2057         struct mbuf *m;
2058         struct mbuf *mp;
2059         struct sockaddr *nam;
2060         struct uio auio;
2061         int flags, error;
2062
2063         if ((slp->ns_flag & SLP_VALID) == 0)
2064                 return;
2065 #ifdef notdef
2066         /*
2067          * Define this to test for nfsds handling this under heavy load.
2068          */
2069         if (waitflag == MB_DONTWAIT) {
2070                 slp->ns_flag |= SLP_NEEDQ; goto dorecs;
2071         }
2072 #endif
2073         auio.uio_td = NULL;
2074         if (so->so_type == SOCK_STREAM) {
2075                 /*
2076                  * If there are already records on the queue, defer soreceive()
2077                  * to an nfsd so that there is feedback to the TCP layer that
2078                  * the nfs servers are heavily loaded.
2079                  */
2080                 if (STAILQ_FIRST(&slp->ns_rec) && waitflag == MB_DONTWAIT) {
2081                         slp->ns_flag |= SLP_NEEDQ;
2082                         goto dorecs;
2083                 }
2084
2085                 /*
2086                  * Do soreceive().
2087                  */
2088                 auio.uio_resid = 1000000000;
2089                 flags = MSG_DONTWAIT;
2090                 error = so_pru_soreceive(so, &nam, &auio, &mp, NULL, &flags);
2091                 if (error || mp == (struct mbuf *)0) {
2092                         if (error == EWOULDBLOCK)
2093                                 slp->ns_flag |= SLP_NEEDQ;
2094                         else
2095                                 slp->ns_flag |= SLP_DISCONN;
2096                         goto dorecs;
2097                 }
2098                 m = mp;
2099                 if (slp->ns_rawend) {
2100                         slp->ns_rawend->m_next = m;
2101                         slp->ns_cc += 1000000000 - auio.uio_resid;
2102                 } else {
2103                         slp->ns_raw = m;
2104                         slp->ns_cc = 1000000000 - auio.uio_resid;
2105                 }
2106                 while (m->m_next)
2107                         m = m->m_next;
2108                 slp->ns_rawend = m;
2109
2110                 /*
2111                  * Now try and parse record(s) out of the raw stream data.
2112                  */
2113                 error = nfsrv_getstream(slp, waitflag);
2114                 if (error) {
2115                         if (error == EPERM)
2116                                 slp->ns_flag |= SLP_DISCONN;
2117                         else
2118                                 slp->ns_flag |= SLP_NEEDQ;
2119                 }
2120         } else {
2121                 do {
2122                         auio.uio_resid = 1000000000;
2123                         flags = MSG_DONTWAIT;
2124                         error = so_pru_soreceive(so, &nam, &auio, &mp, NULL,
2125                             &flags);
2126                         if (mp) {
2127                                 struct nfsrv_rec *rec;
2128                                 int mf = (waitflag & MB_DONTWAIT) ?
2129                                             M_NOWAIT : M_WAITOK;
2130                                 rec = malloc(sizeof(struct nfsrv_rec),
2131                                              M_NFSRVDESC, mf);
2132                                 if (!rec) {
2133                                         if (nam)
2134                                                 FREE(nam, M_SONAME);
2135                                         m_freem(mp);
2136                                         continue;
2137                                 }
2138                                 nfs_realign(&mp, 10 * NFSX_UNSIGNED);
2139                                 rec->nr_address = nam;
2140                                 rec->nr_packet = mp;
2141                                 STAILQ_INSERT_TAIL(&slp->ns_rec, rec, nr_link);
2142                         }
2143                         if (error) {
2144                                 if ((so->so_proto->pr_flags & PR_CONNREQUIRED)
2145                                         && error != EWOULDBLOCK) {
2146                                         slp->ns_flag |= SLP_DISCONN;
2147                                         goto dorecs;
2148                                 }
2149                         }
2150                 } while (mp);
2151         }
2152
2153         /*
2154          * Now try and process the request records, non-blocking.
2155          */
2156 dorecs:
2157         if (waitflag == MB_DONTWAIT &&
2158                 (STAILQ_FIRST(&slp->ns_rec)
2159                  || (slp->ns_flag & (SLP_NEEDQ | SLP_DISCONN))))
2160                 nfsrv_wakenfsd(slp);
2161 }
2162
2163 /*
2164  * Try and extract an RPC request from the mbuf data list received on a
2165  * stream socket. The "waitflag" argument indicates whether or not it
2166  * can sleep.
2167  */
2168 static int
2169 nfsrv_getstream(struct nfssvc_sock *slp, int waitflag)
2170 {
2171         struct mbuf *m, **mpp;
2172         char *cp1, *cp2;
2173         int len;
2174         struct mbuf *om, *m2, *recm;
2175         u_int32_t recmark;
2176
2177         if (slp->ns_flag & SLP_GETSTREAM)
2178                 panic("nfs getstream");
2179         slp->ns_flag |= SLP_GETSTREAM;
2180         for (;;) {
2181             if (slp->ns_reclen == 0) {
2182                 if (slp->ns_cc < NFSX_UNSIGNED) {
2183                         slp->ns_flag &= ~SLP_GETSTREAM;
2184                         return (0);
2185                 }
2186                 m = slp->ns_raw;
2187                 if (m->m_len >= NFSX_UNSIGNED) {
2188                         bcopy(mtod(m, caddr_t), (caddr_t)&recmark, NFSX_UNSIGNED);
2189                         m->m_data += NFSX_UNSIGNED;
2190                         m->m_len -= NFSX_UNSIGNED;
2191                 } else {
2192                         cp1 = (caddr_t)&recmark;
2193                         cp2 = mtod(m, caddr_t);
2194                         while (cp1 < ((caddr_t)&recmark) + NFSX_UNSIGNED) {
2195                                 while (m->m_len == 0) {
2196                                         m = m->m_next;
2197                                         cp2 = mtod(m, caddr_t);
2198                                 }
2199                                 *cp1++ = *cp2++;
2200                                 m->m_data++;
2201                                 m->m_len--;
2202                         }
2203                 }
2204                 slp->ns_cc -= NFSX_UNSIGNED;
2205                 recmark = ntohl(recmark);
2206                 slp->ns_reclen = recmark & ~0x80000000;
2207                 if (recmark & 0x80000000)
2208                         slp->ns_flag |= SLP_LASTFRAG;
2209                 else
2210                         slp->ns_flag &= ~SLP_LASTFRAG;
2211                 if (slp->ns_reclen > NFS_MAXPACKET) {
2212                         slp->ns_flag &= ~SLP_GETSTREAM;
2213                         return (EPERM);
2214                 }
2215             }
2216
2217             /*
2218              * Now get the record part.
2219              *
2220              * Note that slp->ns_reclen may be 0.  Linux sometimes
2221              * generates 0-length RPCs
2222              */
2223             recm = NULL;
2224             if (slp->ns_cc == slp->ns_reclen) {
2225                 recm = slp->ns_raw;
2226                 slp->ns_raw = slp->ns_rawend = (struct mbuf *)0;
2227                 slp->ns_cc = slp->ns_reclen = 0;
2228             } else if (slp->ns_cc > slp->ns_reclen) {
2229                 len = 0;
2230                 m = slp->ns_raw;
2231                 om = (struct mbuf *)0;
2232
2233                 while (len < slp->ns_reclen) {
2234                         if ((len + m->m_len) > slp->ns_reclen) {
2235                                 m2 = m_copym(m, 0, slp->ns_reclen - len,
2236                                         waitflag);
2237                                 if (m2) {
2238                                         if (om) {
2239                                                 om->m_next = m2;
2240                                                 recm = slp->ns_raw;
2241                                         } else
2242                                                 recm = m2;
2243                                         m->m_data += slp->ns_reclen - len;
2244                                         m->m_len -= slp->ns_reclen - len;
2245                                         len = slp->ns_reclen;
2246                                 } else {
2247                                         slp->ns_flag &= ~SLP_GETSTREAM;
2248                                         return (EWOULDBLOCK);
2249                                 }
2250                         } else if ((len + m->m_len) == slp->ns_reclen) {
2251                                 om = m;
2252                                 len += m->m_len;
2253                                 m = m->m_next;
2254                                 recm = slp->ns_raw;
2255                                 om->m_next = (struct mbuf *)0;
2256                         } else {
2257                                 om = m;
2258                                 len += m->m_len;
2259                                 m = m->m_next;
2260                         }
2261                 }
2262                 slp->ns_raw = m;
2263                 slp->ns_cc -= len;
2264                 slp->ns_reclen = 0;
2265             } else {
2266                 slp->ns_flag &= ~SLP_GETSTREAM;
2267                 return (0);
2268             }
2269
2270             /*
2271              * Accumulate the fragments into a record.
2272              */
2273             mpp = &slp->ns_frag;
2274             while (*mpp)
2275                 mpp = &((*mpp)->m_next);
2276             *mpp = recm;
2277             if (slp->ns_flag & SLP_LASTFRAG) {
2278                 struct nfsrv_rec *rec;
2279                 int mf = (waitflag & MB_DONTWAIT) ? M_NOWAIT : M_WAITOK;
2280                 rec = malloc(sizeof(struct nfsrv_rec), M_NFSRVDESC, mf);
2281                 if (!rec) {
2282                     m_freem(slp->ns_frag);
2283                 } else {
2284                     nfs_realign(&slp->ns_frag, 10 * NFSX_UNSIGNED);
2285                     rec->nr_address = (struct sockaddr *)0;
2286                     rec->nr_packet = slp->ns_frag;
2287                     STAILQ_INSERT_TAIL(&slp->ns_rec, rec, nr_link);
2288                 }
2289                 slp->ns_frag = (struct mbuf *)0;
2290             }
2291         }
2292 }
2293
2294 /*
2295  * Parse an RPC header.
2296  */
2297 int
2298 nfsrv_dorec(struct nfssvc_sock *slp, struct nfsd *nfsd,
2299             struct nfsrv_descript **ndp)
2300 {
2301         struct nfsrv_rec *rec;
2302         struct mbuf *m;
2303         struct sockaddr *nam;
2304         struct nfsrv_descript *nd;
2305         int error;
2306
2307         *ndp = NULL;
2308         if ((slp->ns_flag & SLP_VALID) == 0 || !STAILQ_FIRST(&slp->ns_rec))
2309                 return (ENOBUFS);
2310         rec = STAILQ_FIRST(&slp->ns_rec);
2311         STAILQ_REMOVE_HEAD(&slp->ns_rec, nr_link);
2312         nam = rec->nr_address;
2313         m = rec->nr_packet;
2314         free(rec, M_NFSRVDESC);
2315         MALLOC(nd, struct nfsrv_descript *, sizeof (struct nfsrv_descript),
2316                 M_NFSRVDESC, M_WAITOK);
2317         nd->nd_md = nd->nd_mrep = m;
2318         nd->nd_nam2 = nam;
2319         nd->nd_dpos = mtod(m, caddr_t);
2320         error = nfs_getreq(nd, nfsd, TRUE);
2321         if (error) {
2322                 if (nam) {
2323                         FREE(nam, M_SONAME);
2324                 }
2325                 free((caddr_t)nd, M_NFSRVDESC);
2326                 return (error);
2327         }
2328         *ndp = nd;
2329         nfsd->nfsd_nd = nd;
2330         return (0);
2331 }
2332
2333 /*
2334  * Search for a sleeping nfsd and wake it up.
2335  * SIDE EFFECT: If none found, set NFSD_CHECKSLP flag, so that one of the
2336  * running nfsds will go look for the work in the nfssvc_sock list.
2337  */
2338 void
2339 nfsrv_wakenfsd(struct nfssvc_sock *slp)
2340 {
2341         struct nfsd *nd;
2342
2343         if ((slp->ns_flag & SLP_VALID) == 0)
2344                 return;
2345         for (nd = nfsd_head.tqh_first; nd != 0; nd = nd->nfsd_chain.tqe_next) {
2346                 if (nd->nfsd_flag & NFSD_WAITING) {
2347                         nd->nfsd_flag &= ~NFSD_WAITING;
2348                         if (nd->nfsd_slp)
2349                                 panic("nfsd wakeup");
2350                         slp->ns_sref++;
2351                         nd->nfsd_slp = slp;
2352                         wakeup((caddr_t)nd);
2353                         return;
2354                 }
2355         }
2356         slp->ns_flag |= SLP_DOREC;
2357         nfsd_head_flag |= NFSD_CHECKSLP;
2358 }
2359 #endif /* NFS_NOSERVER */