bsd/miscfs/fifofs/fifo_vnops.c

   1 /*
   2  * Copyright (c) 2000-2004 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_OSREFERENCE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License.  The rights granted to you under the
  10  * License may not be used to create, or enable the creation or
  11  * redistribution of, unlawful or unlicensed copies of an Apple operating
  12  * system, or to circumvent, violate, or enable the circumvention or
  13  * violation of, any terms of an Apple operating system software license
  14  * agreement.
  15  *
  16  * Please obtain a copy of the License at
  17  * http://www.opensource.apple.com/apsl/ and read it before using this
  18  * file.
  19  *
  20  * The Original Code and all software distributed under the License are
  21  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  22  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  23  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  24  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  25  * Please see the License for the specific language governing rights and
  26  * limitations under the License.
  27  *
  28  * @APPLE_LICENSE_OSREFERENCE_HEADER_END@
  29  */
  30 /* Copyright (c) 1995 NeXT Computer, Inc. All Rights Reserved */
  31 /*
  32  * Copyright (c) 1990, 1993, 1995
  33  *      The Regents of the University of California.  All rights reserved.
  34  *
  35  * Redistribution and use in source and binary forms, with or without
  36  * modification, are permitted provided that the following conditions
  37  * are met:
  38  * 1. Redistributions of source code must retain the above copyright
  39  *    notice, this list of conditions and the following disclaimer.
  40  * 2. Redistributions in binary form must reproduce the above copyright
  41  *    notice, this list of conditions and the following disclaimer in the
  42  *    documentation and/or other materials provided with the distribution.
  43  * 3. All advertising materials mentioning features or use of this software
  44  *    must display the following acknowledgement:
  45  *      This product includes software developed by the University of
  46  *      California, Berkeley and its contributors.
  47  * 4. Neither the name of the University nor the names of its contributors
  48  *    may be used to endorse or promote products derived from this software
  49  *    without specific prior written permission.
  50  *
  51  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  52  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  53  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  54  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  55  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  56  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  57  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  58  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  59  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  60  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  61  * SUCH DAMAGE.
  62  *
  63  *      @(#)fifo_vnops.c        8.4 (Berkeley) 8/10/94
  64  */
  65
  66 #include <sys/param.h>
  67 #include <sys/proc.h>
  68 #include <sys/time.h>
  69 #include <sys/namei.h>
  70 #include <sys/vnode_internal.h>
  71 #include <sys/socket.h>
  72 #include <sys/socketvar.h>
  73 #include <sys/stat.h>
  74 #include <sys/systm.h>
  75 #include <sys/ioctl.h>
  76 #include <sys/file_internal.h>
  77 #include <sys/errno.h>
  78 #include <sys/malloc.h>
  79 #include <miscfs/fifofs/fifo.h>
  80 #include <vfs/vfs_support.h>
  81
  82 #define VOPFUNC int (*)(void *)
  83
  84 extern int      soo_ioctl(struct fileproc *fp, u_long cmd, caddr_t data, struct proc *p);
  85 extern int      soo_select(struct fileproc *fp, int which, void * wql, struct proc *p);
  86
  87 int (**fifo_vnodeop_p)(void *);
  88 struct vnodeopv_entry_desc fifo_vnodeop_entries[] = {
  89         { &vnop_default_desc, (VOPFUNC)vn_default_error },
  90         { &vnop_lookup_desc, (VOPFUNC)fifo_lookup },            /* lookup */
  91         { &vnop_create_desc, (VOPFUNC)err_create },             /* create */
  92         { &vnop_mknod_desc, (VOPFUNC)err_mknod },               /* mknod */
  93         { &vnop_open_desc, (VOPFUNC)fifo_open },                        /* open */
  94         { &vnop_close_desc, (VOPFUNC)fifo_close },              /* close */
  95         { &vnop_access_desc, (VOPFUNC)fifo_access },            /* access */
  96         { &vnop_getattr_desc, (VOPFUNC)fifo_getattr },          /* getattr */
  97         { &vnop_setattr_desc, (VOPFUNC)fifo_setattr },          /* setattr */
  98         { &vnop_read_desc, (VOPFUNC)fifo_read },                        /* read */
  99         { &vnop_write_desc, (VOPFUNC)fifo_write },              /* write */
 100         { &vnop_ioctl_desc, (VOPFUNC)fifo_ioctl },              /* ioctl */
 101         { &vnop_select_desc, (VOPFUNC)fifo_select },            /* select */
 102         { &vnop_revoke_desc, (VOPFUNC)fifo_revoke },            /* revoke */
 103         { &vnop_mmap_desc, (VOPFUNC)err_mmap },                 /* mmap */
 104         { &vnop_fsync_desc, (VOPFUNC)fifo_fsync },              /* fsync */
 105         { &vnop_remove_desc, (VOPFUNC)err_remove },             /* remove */
 106         { &vnop_link_desc, (VOPFUNC)err_link },                 /* link */
 107         { &vnop_rename_desc, (VOPFUNC)err_rename },             /* rename */
 108         { &vnop_mkdir_desc, (VOPFUNC)err_mkdir },               /* mkdir */
 109         { &vnop_rmdir_desc, (VOPFUNC)err_rmdir },               /* rmdir */
 110         { &vnop_symlink_desc, (VOPFUNC)err_symlink },           /* symlink */
 111         { &vnop_readdir_desc, (VOPFUNC)err_readdir },           /* readdir */
 112         { &vnop_readlink_desc, (VOPFUNC)err_readlink },         /* readlink */
 113         { &vnop_inactive_desc, (VOPFUNC)fifo_inactive },                /* inactive */
 114         { &vnop_reclaim_desc, (VOPFUNC)fifo_reclaim },          /* reclaim */
 115         { &vnop_strategy_desc, (VOPFUNC)err_strategy },         /* strategy */
 116         { &vnop_pathconf_desc, (VOPFUNC)fifo_pathconf },                /* pathconf */
 117         { &vnop_advlock_desc, (VOPFUNC)fifo_advlock },          /* advlock */
 118         { &vnop_bwrite_desc, (VOPFUNC)fifo_bwrite },            /* bwrite */
 119         { &vnop_pagein_desc, (VOPFUNC)err_pagein },             /* Pagein */
 120         { &vnop_pageout_desc, (VOPFUNC)err_pageout },           /* Pageout */
 121         { &vnop_copyfile_desc, (VOPFUNC)err_copyfile },         /* Copyfile */
 122         { &vnop_blktooff_desc, (VOPFUNC)err_blktooff },         /* blktooff */
 123         { &vnop_offtoblk_desc, (VOPFUNC)err_offtoblk },         /* offtoblk */
 124         { &vnop_blockmap_desc, (VOPFUNC)err_blockmap },                 /* blockmap */
 125         { (struct vnodeop_desc*)NULL, (int(*)())NULL }
 126 };
 127 struct vnodeopv_desc fifo_vnodeop_opv_desc =
 128         { &fifo_vnodeop_p, fifo_vnodeop_entries };
 129
 130 /*
 131  * Trivial lookup routine that always fails.
 132  */
 133 /* ARGSUSED */
 134 int
 135 fifo_lookup(ap)
 136         struct vnop_lookup_args /* {
 137                 struct vnode * a_dvp;
 138                 struct vnode ** a_vpp;
 139                 struct componentname * a_cnp;
 140                 vfs_context_t a_context;
 141         } */ *ap;
 142 {
 143
 144         *ap->a_vpp = NULL;
 145         return (ENOTDIR);
 146 }
 147
 148 /*
 149  * Open called to set up a new instance of a fifo or
 150  * to find an active instance of a fifo.
 151  */
 152 /* ARGSUSED */
 153 int
 154 fifo_open(ap)
 155         struct vnop_open_args /* {
 156                 struct vnode *a_vp;
 157                 int  a_mode;
 158                 vfs_context_t a_context;
 159         } */ *ap;
 160 {
 161         struct vnode *vp = ap->a_vp;
 162         struct fifoinfo *fip;
 163         struct socket *rso, *wso;
 164         int error;
 165
 166         vnode_lock(vp);
 167
 168 retry:
 169
 170         fip = vp->v_fifoinfo;
 171
 172         if (fip == (struct fifoinfo *)0)
 173                 panic("fifo_open with no fifoinfo");
 174
 175         if ((fip->fi_flags & FIFO_CREATED) == 0) {
 176                 if (fip->fi_flags & FIFO_INCREATE) {
 177                         fip->fi_flags |= FIFO_CREATEWAIT;
 178                         error = msleep(&fip->fi_flags, &vp->v_lock, PRIBIO | PCATCH, "fifocreatewait", 0);
 179                         if (error) {
 180                                 vnode_unlock(vp);
 181                                 return(error);
 182                         }
 183                         goto retry;
 184                 } else {
 185                         fip->fi_flags |= FIFO_INCREATE;
 186                         vnode_unlock(vp);
 187                         if ( (error = socreate(AF_LOCAL, &rso, SOCK_STREAM, 0)) ) {
 188                                 goto bad1;
 189                         }
 190                         fip->fi_readsock = rso;
 191
 192                         if ( (error = socreate(AF_LOCAL, &wso, SOCK_STREAM, 0)) ) {
 193                                 (void)soclose(rso);
 194                                 goto bad1;
 195                         }
 196                         fip->fi_writesock = wso;
 197
 198                         if ( (error = soconnect2(wso, rso)) ) {
 199                                 (void)soclose(wso);
 200                                 (void)soclose(rso);
 201                                 goto bad1;
 202                         }
 203                         fip->fi_readers = fip->fi_writers = 0;
 204
 205                 socket_lock(wso, 1);
 206                         wso->so_state |= SS_CANTRCVMORE;
 207                         wso->so_snd.sb_lowat = PIPE_BUF;
 208 #if 0
 209                         /* Because all the unp is protected by single mutex
 210                          * doing it in two step may actually cause problems
 211                          * as it opens up window between the drop and acquire
 212                          */
 213                 socket_unlock(wso, 1);
 214
 215                 socket_lock(rso, 1);
 216 #endif
 217                         rso->so_state |= SS_CANTSENDMORE;
 218                 socket_unlock(wso, 1);
 219
 220                         vnode_lock(vp);
 221                         fip->fi_flags |= FIFO_CREATED;
 222                         fip->fi_flags &= ~FIFO_INCREATE;
 223
 224                         if ((fip->fi_flags & FIFO_CREATEWAIT)) {
 225                                 fip->fi_flags &= ~FIFO_CREATEWAIT;
 226                                 wakeup(&fip->fi_flags);
 227                         }
 228                         /* vnode lock is held  to process further */
 229                 }
 230         }
 231
 232         /* vnode is locked at this point */
 233         /* fifo in created already */
 234         if (ap->a_mode & FREAD) {
 235                 fip->fi_readers++;
 236                 if (fip->fi_readers == 1) {
 237                         socket_lock(fip->fi_writesock, 1);
 238                         fip->fi_writesock->so_state &= ~SS_CANTSENDMORE;
 239                         socket_unlock(fip->fi_writesock, 1);
 240
 241                         if (fip->fi_writers > 0)
 242                                 wakeup((caddr_t)&fip->fi_writers);
 243                 }
 244         }
 245         if (ap->a_mode & FWRITE) {
 246                 fip->fi_writers++;
 247                 if (fip->fi_writers == 1) {
 248                         socket_lock(fip->fi_readsock, 1);
 249                         fip->fi_readsock->so_state &= ~SS_CANTRCVMORE;
 250                         socket_unlock(fip->fi_readsock, 1);
 251
 252                         if (fip->fi_readers > 0)
 253                                 wakeup((caddr_t)&fip->fi_readers);
 254                 }
 255         }
 256         if ((ap->a_mode & FREAD) && (ap->a_mode & O_NONBLOCK) == 0) {
 257                 if (fip->fi_writers == 0) {
 258                         error = msleep((caddr_t)&fip->fi_readers, &vp->v_lock,
 259                                         PCATCH | PSOCK, "fifoor", 0);
 260                         if (error)
 261                                 goto bad;
 262                         if (fip->fi_readers == 1) {
 263                                 if (fip->fi_writers > 0)
 264                                         wakeup((caddr_t)&fip->fi_writers);
 265                         }
 266                 }
 267         }
 268         if (ap->a_mode & FWRITE) {
 269                 if (ap->a_mode & O_NONBLOCK) {
 270                         if (fip->fi_readers == 0) {
 271                                         error = ENXIO;
 272                                         goto bad;
 273                         }
 274                 } else {
 275                         if (fip->fi_readers == 0) {
 276                                 error = msleep((caddr_t)&fip->fi_writers,&vp->v_lock,
 277                                                 PCATCH | PSOCK, "fifoow", 0);
 278                                 if (error)
 279                                         goto bad;
 280                                 if (fip->fi_writers == 1) {
 281                                         if (fip->fi_readers > 0)
 282                                                 wakeup((caddr_t)&fip->fi_readers);
 283                                 }
 284                         }
 285                 }
 286         }
 287
 288         vnode_unlock(vp);
 289         return (0);
 290 bad:
 291         fifo_close_internal(vp, ap->a_mode, ap->a_context, 1);
 292
 293         vnode_unlock(vp);
 294         return (error);
 295 bad1:
 296         vnode_lock(vp);
 297
 298         fip->fi_flags &= ~FIFO_INCREATE;
 299
 300         if ((fip->fi_flags & FIFO_CREATEWAIT)) {
 301                 fip->fi_flags &= ~FIFO_CREATEWAIT;
 302                 wakeup(&fip->fi_flags);
 303         }
 304         vnode_unlock(vp);
 305
 306         return (error);
 307 }
 308
 309 /*
 310  * Vnode op for read
 311  */
 312 int
 313 fifo_read(ap)
 314         struct vnop_read_args /* {
 315                 struct vnode *a_vp;
 316                 struct uio *a_uio;
 317                 int  a_ioflag;
 318                 vfs_context_t a_context;
 319         } */ *ap;
 320 {
 321         struct uio *uio = ap->a_uio;
 322         struct socket *rso = ap->a_vp->v_fifoinfo->fi_readsock;
 323         int error, startresid;
 324         int rflags;
 325
 326 #if DIAGNOSTIC
 327         if (uio->uio_rw != UIO_READ)
 328                 panic("fifo_read mode");
 329 #endif
 330         if (uio_resid(uio) == 0)
 331                 return (0);
 332
 333         rflags = (ap->a_ioflag & IO_NDELAY) ? MSG_NBIO : 0;
 334
 335         // LP64todo - fix this!
 336         startresid = uio_resid(uio);
 337
 338         /* fifo conformance - if we have a reader open on the fifo but no
 339          * writers then we need to make sure we do not block.  We do that by
 340          * checking the receive buffer and if empty set error to EWOULDBLOCK.
 341          * If error is set to EWOULDBLOCK we skip the call into soreceive
 342          */
 343         error = 0;
 344         if (ap->a_vp->v_fifoinfo->fi_writers < 1) {
 345                 socket_lock(rso, 1);
 346                 error = (rso->so_rcv.sb_cc == 0) ? EWOULDBLOCK : 0;
 347                 socket_unlock(rso, 1);
 348         }
 349
 350         /* skip soreceive to avoid blocking when we have no writers */
 351         if (error != EWOULDBLOCK) {
 352                 error = soreceive(rso, (struct sockaddr **)0, uio, (struct mbuf **)0,
 353                                                 (struct mbuf **)0, &rflags);
 354         }
 355         else {
 356                 /* clear EWOULDBLOCK and return EOF (zero) */
 357                 error = 0;
 358         }
 359         /*
 360          * Clear EOF indication after first such return.
 361          */
 362         if (uio_resid(uio) == startresid) {
 363                 socket_lock(rso, 1);
 364                 rso->so_state &= ~SS_CANTRCVMORE;
 365                 socket_unlock(rso, 1);
 366         }
 367         return (error);
 368 }
 369
 370 /*
 371  * Vnode op for write
 372  */
 373 int
 374 fifo_write(ap)
 375         struct vnop_write_args /* {
 376                 struct vnode *a_vp;
 377                 struct uio *a_uio;
 378                 int  a_ioflag;
 379                 vfs_context_t a_context;
 380         } */ *ap;
 381 {
 382         struct socket *wso = ap->a_vp->v_fifoinfo->fi_writesock;
 383         int error;
 384
 385 #if DIAGNOSTIC
 386         if (ap->a_uio->uio_rw != UIO_WRITE)
 387                 panic("fifo_write mode");
 388 #endif
 389         error = sosend(wso, (struct sockaddr *)0, ap->a_uio, 0,
 390                        (struct mbuf *)0, (ap->a_ioflag & IO_NDELAY) ? MSG_NBIO : 0);
 391
 392         return (error);
 393 }
 394
 395 /*
 396  * Device ioctl operation.
 397  */
 398 int
 399 fifo_ioctl(ap)
 400         struct vnop_ioctl_args /* {
 401                 struct vnode *a_vp;
 402                 int  a_command;
 403                 caddr_t  a_data;
 404                 int  a_fflag;
 405                 vfs_context_t a_context;
 406         } */ *ap;
 407 {
 408         struct proc *p = vfs_context_proc(ap->a_context);
 409         struct fileproc filetmp;
 410         struct fileglob filefg;
 411         int error;
 412
 413         if (ap->a_command == FIONBIO)
 414                 return (0);
 415         bzero(&filetmp, sizeof(struct fileproc));
 416         filetmp.f_fglob = &filefg;
 417         if (ap->a_fflag & FREAD) {
 418                 filetmp.f_fglob->fg_data = (caddr_t)ap->a_vp->v_fifoinfo->fi_readsock;
 419                 error = soo_ioctl(&filetmp, ap->a_command, ap->a_data, p);
 420                 if (error)
 421                         return (error);
 422         }
 423         if (ap->a_fflag & FWRITE) {
 424                 filetmp.f_fglob->fg_data = (caddr_t)ap->a_vp->v_fifoinfo->fi_writesock;
 425                 error = soo_ioctl(&filetmp, ap->a_command, ap->a_data, p);
 426                 if (error)
 427                         return (error);
 428         }
 429         return (0);
 430 }
 431
 432 int
 433 fifo_select(ap)
 434         struct vnop_select_args /* {
 435                 struct vnode *a_vp;
 436                 int  a_which;
 437                 int  a_fflags;
 438                 void * a_wql;
 439                 vfs_context_t a_context;
 440         } */ *ap;
 441 {
 442         struct proc *p = vfs_context_proc(ap->a_context);
 443         struct fileproc filetmp;
 444         struct fileglob filefg;
 445         int ready;
 446
 447         bzero(&filetmp, sizeof(struct fileproc));
 448         filetmp.f_fglob = &filefg;
 449         if (ap->a_which & FREAD) {
 450                 filetmp.f_fglob->fg_data = (caddr_t)ap->a_vp->v_fifoinfo->fi_readsock;
 451                 ready = soo_select(&filetmp, ap->a_which, ap->a_wql, p);
 452                 if (ready)
 453                         return (ready);
 454         }
 455         if (ap->a_which & FWRITE) {
 456                 filetmp.f_fglob->fg_data = (caddr_t)ap->a_vp->v_fifoinfo->fi_writesock;
 457                 ready = soo_select(&filetmp, ap->a_which, ap->a_wql, p);
 458                 if (ready)
 459                         return (ready);
 460         }
 461         return (0);
 462 }
 463
 464 int
 465 fifo_inactive(__unused struct vnop_inactive_args *ap)
 466 {
 467         return (0);
 468 }
 469
 470
 471 /*
 472  * Device close routine
 473  */
 474 int
 475 fifo_close(ap)
 476         struct vnop_close_args /* {
 477                 struct vnode *a_vp;
 478                 int  a_fflag;
 479                 vfs_context_t a_context;
 480         } */ *ap;
 481 {
 482         return fifo_close_internal(ap->a_vp, ap->a_fflag, ap->a_context, 0);
 483 }
 484
 485 int
 486 fifo_close_internal(vnode_t vp, int fflag, __unused vfs_context_t context, int locked)
 487 {
 488         register struct fifoinfo *fip = vp->v_fifoinfo;
 489         int error1, error2;
 490         struct socket *rso;
 491         struct socket *wso;
 492
 493         if (!locked)
 494                 vnode_lock(vp);
 495
 496         if ((fip->fi_flags & FIFO_CREATED) == 0) {
 497                 if (!locked)
 498                         vnode_unlock(vp);
 499                 return(0);
 500
 501         }
 502
 503         if (fflag & FREAD) {
 504                 fip->fi_readers--;
 505                 if (fip->fi_readers == 0){
 506                         socket_lock(fip->fi_writesock, 1);
 507                         socantsendmore(fip->fi_writesock);
 508                         socket_unlock(fip->fi_writesock, 1);
 509                 }
 510         }
 511
 512         if (fflag & FWRITE) {
 513                 fip->fi_writers--;
 514                 if (fip->fi_writers == 0) {
 515                         socket_lock(fip->fi_readsock, 1);
 516                         socantrcvmore(fip->fi_readsock);
 517                         socket_unlock(fip->fi_readsock, 1);
 518                 }
 519         }
 520 #if 0
 521         if (vnode_isinuse_locked(vp, 0, 1)) {
 522                 if (!locked)
 523                         vnode_unlock(vp);
 524                 return (0);
 525         }
 526 #endif
 527
 528         if (fip->fi_writers || fip->fi_readers) {
 529                 if (!locked)
 530                         vnode_unlock(vp);
 531                 return (0);
 532         }
 533
 534         wso = fip->fi_writesock;
 535         rso = fip->fi_readsock;
 536         fip->fi_readsock = 0;
 537         fip->fi_writesock = 0;
 538         fip->fi_flags &= ~FIFO_CREATED;
 539         if (!locked)
 540                 vnode_unlock(vp);
 541         error1 = soclose(rso);
 542         error2 = soclose(wso);
 543
 544         if (error1)
 545                 return (error1);
 546         return (error2);
 547 }
 548
 549
 550 /*
 551  * Print out internal contents of a fifo vnode.
 552  */
 553 void
 554 fifo_printinfo(vp)
 555         struct vnode *vp;
 556 {
 557         register struct fifoinfo *fip = vp->v_fifoinfo;
 558
 559         printf(", fifo with %d readers and %d writers",
 560                 fip->fi_readers, fip->fi_writers);
 561 }
 562
 563 /*
 564  * Return POSIX pathconf information applicable to fifo's.
 565  */
 566 int
 567 fifo_pathconf(ap)
 568         struct vnop_pathconf_args /* {
 569                 struct vnode *a_vp;
 570                 int a_name;
 571                 int *a_retval;
 572                 vfs_context_t a_context;
 573         } */ *ap;
 574 {
 575
 576         switch (ap->a_name) {
 577         case _PC_LINK_MAX:
 578                 *ap->a_retval = LINK_MAX;
 579                 return (0);
 580         case _PC_PIPE_BUF:
 581                 *ap->a_retval = PIPE_BUF;
 582                 return (0);
 583         case _PC_CHOWN_RESTRICTED:
 584                 *ap->a_retval = 1;
 585                 return (0);
 586         default:
 587                 return (EINVAL);
 588         }
 589         /* NOTREACHED */
 590 }
 591
 592 /*
 593  * Fifo failed operation
 594  */
 595 int
 596 fifo_ebadf(__unused void *dummy)
 597 {
 598
 599         return (EBADF);
 600 }
 601
 602 /*
 603  * Fifo advisory byte-level locks.
 604  */
 605 int
 606 fifo_advlock(__unused struct vnop_advlock_args *ap)
 607 {
 608
 609         return (ENOTSUP);
 610 }
 611