bsd/miscfs/fdesc/fdesc_vnops.c

   1 /*
   2  * Copyright (c) 2000-2006 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_OSREFERENCE_LICENSE_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 License
  10  * may not be used to create, or enable the creation or redistribution of,
  11  * unlawful or unlicensed copies of an Apple operating system, or to
  12  * circumvent, violate, or enable the circumvention or violation of, any
  13  * terms of an Apple operating system software license agreement.
  14  *
  15  * Please obtain a copy of the License at
  16  * http://www.opensource.apple.com/apsl/ and read it before using this file.
  17  *
  18  * The Original Code and all software distributed under the License are
  19  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  20  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  21  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  22  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  23  * Please see the License for the specific language governing rights and
  24  * limitations under the License.
  25  *
  26  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  27  */
  28 /* Copyright (c) 1995 NeXT Computer, Inc. All Rights Reserved */
  29 /*
  30  * Copyright (c) 1992, 1993
  31  *      The Regents of the University of California.  All rights reserved.
  32  *
  33  * This code is derived from software donated to Berkeley by
  34  * Jan-Simon Pendry.
  35  *
  36  * Redistribution and use in source and binary forms, with or without
  37  * modification, are permitted provided that the following conditions
  38  * are met:
  39  * 1. Redistributions of source code must retain the above copyright
  40  *    notice, this list of conditions and the following disclaimer.
  41  * 2. Redistributions in binary form must reproduce the above copyright
  42  *    notice, this list of conditions and the following disclaimer in the
  43  *    documentation and/or other materials provided with the distribution.
  44  * 3. All advertising materials mentioning features or use of this software
  45  *    must display the following acknowledgement:
  46  *      This product includes software developed by the University of
  47  *      California, Berkeley and its contributors.
  48  * 4. Neither the name of the University nor the names of its contributors
  49  *    may be used to endorse or promote products derived from this software
  50  *    without specific prior written permission.
  51  *
  52  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  53  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  54  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  55  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  56  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  57  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  58  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  59  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  60  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  61  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  62  * SUCH DAMAGE.
  63  *
  64  *      @(#)fdesc_vnops.c       8.17 (Berkeley) 5/22/95
  65  *
  66  */
  67
  68 /*
  69  * /dev/fd Filesystem
  70  */
  71
  72 #include <sys/param.h>
  73 #include <sys/systm.h>
  74 #include <sys/types.h>
  75 #include <sys/time.h>
  76 #include <sys/proc_internal.h>
  77 #include <sys/kernel.h> /* boottime */
  78 #include <sys/resourcevar.h>
  79 #include <sys/filedesc.h>
  80 #include <sys/kauth.h>
  81 #include <sys/vnode_internal.h>
  82 #include <sys/malloc.h>
  83 #include <sys/file_internal.h>
  84 #include <sys/stat.h>
  85 #include <sys/mount_internal.h>
  86 #include <sys/namei.h>
  87 #include <sys/dirent.h>
  88 #include <sys/ubc.h>
  89 #include <sys/socketvar.h>
  90 #include <sys/pipe.h>
  91 #include <sys/uio_internal.h>
  92 #include <miscfs/fdesc/fdesc.h>
  93 #include <vfs/vfs_support.h>
  94 #include <pexpert/pexpert.h>
  95
  96 /* XXX should be prototyped in header for here, kern_descrip.c */
  97 extern int soo_stat(struct socket *so, void *ub, int isstat64);
  98
  99 #define FDL_WANT        0x01
 100 #define FDL_LOCKED      0x02
 101 static int fdcache_lock;
 102
 103
 104 #if (FD_STDIN != FD_STDOUT-1) || (FD_STDOUT != FD_STDERR-1)
 105 FD_STDIN, FD_STDOUT, FD_STDERR must be a sequence n, n+1, n+2
 106 #endif
 107
 108 #define NFDCACHE 3
 109
 110 #define FD_NHASH(ix) \
 111         (&fdhashtbl[(ix) & fdhash])
 112 LIST_HEAD(fdhashhead, fdescnode) *fdhashtbl;
 113 u_long fdhash;
 114
 115 static int fdesc_attr(int fd, struct vnode_attr *vap, vfs_context_t a_context);
 116
 117
 118 /*
 119  * Initialise cache headers
 120  */
 121 int
 122 fdesc_init(__unused struct vfsconf *vfsp)
 123 {
 124
 125         fdhashtbl = hashinit(NFDCACHE, M_CACHE, &fdhash);
 126
 127         return( 0 );
 128 }
 129
 130 int
 131 fdesc_allocvp(fdntype ftype, int ix, struct mount *mp, struct vnode **vpp,
 132               enum vtype vtype)
 133 {
 134         struct fdhashhead *fc;
 135         struct fdescnode *fd;
 136         int error = 0;
 137         int vid = 0;
 138         struct vnode_fsparam vfsp;
 139
 140         fc = FD_NHASH(ix);
 141 loop:
 142         for (fd = fc->lh_first; fd != 0; fd = fd->fd_hash.le_next) {
 143                 if (fd->fd_ix == ix && vnode_mount(fd->fd_vnode) == mp) {
 144                         /*
 145                          * doing a vnode_getwithvid isn't technically
 146                          * necessary since fdesc is an unsafe filesystem
 147                          * and we're running behind a funnel at this point
 148                          * however, vnode_get always succeeds, which isn't
 149                          * what we want if this vnode is in the process of
 150                          * being terminated
 151                          */
 152                         vid = vnode_vid(fd->fd_vnode);
 153
 154                         if (vnode_getwithvid(fd->fd_vnode, vid))
 155                                 goto loop;
 156                         *vpp = fd->fd_vnode;
 157                         (*vpp)->v_type = vtype;
 158
 159                         return (error);
 160                 }
 161         }
 162
 163         /*
 164          * otherwise lock the array while we call getnewvnode
 165          * since that can block.
 166          */
 167         if (fdcache_lock & FDL_LOCKED) {
 168                 fdcache_lock |= FDL_WANT;
 169                 sleep((caddr_t) &fdcache_lock, PINOD);
 170                 goto loop;
 171         }
 172         fdcache_lock |= FDL_LOCKED;
 173
 174         MALLOC(fd, void *, sizeof(struct fdescnode), M_TEMP, M_WAITOK);
 175
 176         vfsp.vnfs_mp = mp;
 177         vfsp.vnfs_vtype = vtype;
 178         vfsp.vnfs_str = "fdesc";
 179         vfsp.vnfs_dvp = NULL;
 180         vfsp.vnfs_fsnode = fd;
 181         vfsp.vnfs_cnp = NULL;
 182         vfsp.vnfs_vops = fdesc_vnodeop_p;
 183         vfsp.vnfs_rdev = 0;
 184         vfsp.vnfs_filesize = 0;
 185         vfsp.vnfs_flags = VNFS_NOCACHE | VNFS_CANTCACHE;
 186         vfsp.vnfs_marksystem = 0;
 187         if (ftype == Froot)
 188                 vfsp.vnfs_markroot = 1;
 189         else
 190                 vfsp.vnfs_markroot = 0;
 191
 192         error = vnode_create(VNCREATE_FLAVOR, VCREATESIZE, &vfsp, vpp);
 193         if (error) {
 194                 FREE(fd, M_TEMP);
 195                 goto out;
 196         }
 197         (*vpp)->v_tag = VT_FDESC;
 198         fd->fd_vnode = *vpp;
 199         fd->fd_type = ftype;
 200         fd->fd_fd = -1;
 201         fd->fd_link = NULL;
 202         fd->fd_ix = ix;
 203         LIST_INSERT_HEAD(fc, fd, fd_hash);
 204
 205 out:
 206         fdcache_lock &= ~FDL_LOCKED;
 207
 208         if (fdcache_lock & FDL_WANT) {
 209                 fdcache_lock &= ~FDL_WANT;
 210                 wakeup((caddr_t) &fdcache_lock);
 211         }
 212
 213         return (error);
 214 }
 215
 216 /*
 217  * vp is the current namei directory
 218  * ndp is the name to locate in that directory...
 219  */
 220 int
 221 fdesc_lookup(struct vnop_lookup_args *ap)
 222 {
 223         struct vnode **vpp = ap->a_vpp;
 224         struct vnode *dvp = ap->a_dvp;
 225         struct componentname *cnp = ap->a_cnp;
 226         char *pname = cnp->cn_nameptr;
 227         struct proc *p = vfs_context_proc(ap->a_context);
 228         int numfiles = p->p_fd->fd_nfiles;
 229         int fd;
 230         int error;
 231         struct vnode *fvp;
 232         const char *ln;
 233
 234         if (cnp->cn_namelen == 1 && *pname == '.') {
 235                 *vpp = dvp;
 236
 237                 if ( (error = vnode_get(dvp)) ) {
 238                         return(error);
 239                 }
 240                 return (0);
 241         }
 242
 243         switch (VTOFDESC(dvp)->fd_type) {
 244         default:
 245         case Flink:
 246         case Fdesc:
 247                 /* should never happen */
 248                 error = ENOTDIR;
 249                 goto bad;
 250
 251         case Froot:
 252                 if (cnp->cn_namelen == 2 && bcmp(pname, "fd", 2) == 0) {
 253                         error = fdesc_allocvp(Fdevfd, FD_DEVFD, dvp->v_mount, &fvp, VDIR);
 254                         if (error)
 255                                 goto bad;
 256                         *vpp = fvp;
 257                         return (0);
 258                 }
 259
 260                 ln = NULL;
 261                 switch (cnp->cn_namelen) {
 262                 case 5:
 263                         if (bcmp(pname, "stdin", 5) == 0) {
 264                                 ln = "fd/0";
 265                                 fd = FD_STDIN;
 266                         }
 267                         break;
 268                 case 6:
 269                         if (bcmp(pname, "stdout", 6) == 0) {
 270                                 ln = "fd/1";
 271                                 fd = FD_STDOUT;
 272                         } else
 273                         if (bcmp(pname, "stderr", 6) == 0) {
 274                                 ln = "fd/2";
 275                                 fd = FD_STDERR;
 276                         }
 277                         break;
 278                 }
 279
 280                 if (ln) {
 281                         error = fdesc_allocvp(Flink, fd, dvp->v_mount, &fvp, VLNK);
 282                         if (error)
 283                                 goto bad;
 284                         VTOFDESC(fvp)->fd_link = ln;
 285                         *vpp = fvp;
 286                         return (0);
 287                 } else {
 288                         error = ENOENT;
 289                         goto bad;
 290                 }
 291
 292                 /* FALL THROUGH */
 293
 294         case Fdevfd:
 295                 if (cnp->cn_namelen == 2 && bcmp(pname, "..", 2) == 0) {
 296                         if ((error = fdesc_root(dvp->v_mount, vpp, ap->a_context)))
 297                                 goto bad;
 298                         return (0);
 299                 }
 300
 301                 fd = 0;
 302                 while (*pname >= '0' && *pname <= '9') {
 303                         fd = 10 * fd + *pname++ - '0';
 304                         if (fd >= numfiles)
 305                                 break;
 306                 }
 307
 308                 if (*pname != '\0') {
 309                         error = ENOENT;
 310                         goto bad;
 311                 }
 312
 313                 if (fd < 0 || fd >= numfiles ||
 314                                 *fdfile(p, fd) == NULL ||
 315                                 (*fdflags(p, fd) & UF_RESERVED)) {
 316                         error = EBADF;
 317                         goto bad;
 318                 }
 319
 320                 error = fdesc_allocvp(Fdesc, FD_DESC+fd, dvp->v_mount, &fvp, VNON);
 321                 if (error)
 322                         goto bad;
 323                 VTOFDESC(fvp)->fd_fd = fd;
 324                 *vpp = fvp;
 325                 return (0);
 326         }
 327
 328 bad:;
 329         *vpp = NULL;
 330         return (error);
 331 }
 332
 333 int
 334 fdesc_open(struct vnop_open_args *ap)
 335 {
 336         struct vnode *vp = ap->a_vp;
 337         thread_t thr = vfs_context_thread(ap->a_context);
 338         uthread_t uu;
 339         int error = 0;
 340
 341         if (thr == NULL)
 342                 return (EINVAL);
 343
 344         uu = get_bsdthread_info(thr);
 345
 346         switch (VTOFDESC(vp)->fd_type) {
 347         case Fdesc:
 348                 /*
 349                  * XXX Kludge: set uu->uu_dupfd to contain the value of the
 350                  * the file descriptor being sought for duplication. The error
 351                  * return ensures that the vnode for this device will be
 352                  * released by vn_open. Open will detect this special error and
 353                  * take the actions in dupfdopen.  Other callers of vn_open or
 354                  * vnop_open will simply report the error.
 355                  */
 356                 uu->uu_dupfd = VTOFDESC(vp)->fd_fd;     /* XXX */
 357                 error = ENODEV;
 358                 break;
 359         default:        /* Froot / Fdevfd / Flink */
 360                 break;
 361         }
 362
 363         return (error);
 364 }
 365
 366 static int
 367 fdesc_attr(int fd, struct vnode_attr *vap, vfs_context_t a_context)
 368 {
 369         struct fileproc *fp;
 370         struct proc *p = vfs_context_proc(a_context);
 371         struct stat stb;
 372         int error;
 373
 374         if ((error = fp_lookup(p, fd, &fp, 0)))
 375                 return (error);
 376         switch (fp->f_fglob->fg_type) {
 377         case DTYPE_VNODE:
 378                 if((error = vnode_getwithref((struct vnode *) fp->f_fglob->fg_data)) != 0) {
 379                         break;
 380                 }
 381                 if ((error = vnode_authorize((struct vnode *)fp->f_fglob->fg_data,
 382                          NULL,
 383                          KAUTH_VNODE_READ_ATTRIBUTES | KAUTH_VNODE_READ_SECURITY,
 384                          a_context)) == 0)
 385                         error = vnode_getattr((struct vnode *)fp->f_fglob->fg_data, vap, a_context);
 386                 if (error == 0 && vap->va_type == VDIR) {
 387                         /*
 388                          * directories can cause loops in the namespace,
 389                          * so turn off the 'x' bits to avoid trouble.
 390                          *
 391                          * XXX ACLs break this, of course
 392                          */
 393                         vap->va_mode &= ~((VEXEC)|(VEXEC>>3)|(VEXEC>>6));
 394                 }
 395                 (void)vnode_put((struct vnode *) fp->f_fglob->fg_data);
 396                 break;
 397
 398         case DTYPE_SOCKET:
 399         case DTYPE_PIPE:
 400 #if SOCKETS
 401                 if (fp->f_fglob->fg_type == DTYPE_SOCKET)
 402                         error = soo_stat((struct socket *)fp->f_fglob->fg_data, (void *)&stb, 0);
 403                 else
 404 #endif /* SOCKETS */
 405                 error = pipe_stat((struct pipe *)fp->f_fglob->fg_data, (void *)&stb, 0);
 406
 407                 if (error == 0) {
 408                         if (fp->f_fglob->fg_type == DTYPE_SOCKET)
 409                                 VATTR_RETURN(vap, va_type, VSOCK);
 410                         else
 411                                 VATTR_RETURN(vap, va_type, VFIFO);
 412
 413                         VATTR_RETURN(vap, va_mode, stb.st_mode);
 414                         VATTR_RETURN(vap, va_nlink, stb.st_nlink);
 415                         VATTR_RETURN(vap, va_uid, stb.st_uid);
 416                         VATTR_RETURN(vap, va_gid, stb.st_gid);
 417                         VATTR_RETURN(vap, va_fsid, stb.st_dev);
 418                         VATTR_RETURN(vap, va_fileid, stb.st_ino);
 419                         VATTR_RETURN(vap, va_data_size, stb.st_size);
 420                         VATTR_RETURN(vap, va_access_time, stb.st_atimespec);
 421                         VATTR_RETURN(vap, va_modify_time, stb.st_mtimespec);
 422                         VATTR_RETURN(vap, va_change_time, stb.st_ctimespec);
 423                         VATTR_RETURN(vap, va_gen, stb.st_gen);
 424                         VATTR_RETURN(vap, va_flags, stb.st_flags);
 425                         VATTR_RETURN(vap, va_rdev, stb.st_rdev);
 426                         VATTR_RETURN(vap, va_total_alloc, stb.st_blocks * stb.st_blksize);
 427                         VATTR_RETURN(vap, va_acl, NULL);
 428                 }
 429                 break;
 430
 431         default:
 432                 error = EBADF;
 433         }
 434
 435         fp_drop(p, fd, fp, 0);
 436         return (error);
 437 }
 438
 439 int
 440 fdesc_getattr(struct vnop_getattr_args *ap)
 441 {
 442         struct vnode *vp = ap->a_vp;
 443         struct vnode_attr *vap = ap->a_vap;
 444         unsigned fd;
 445         int error = 0;
 446         struct timespec ts;
 447
 448         switch (VTOFDESC(vp)->fd_type) {
 449         case Froot:
 450         case Fdevfd:
 451         case Flink:
 452                 VATTR_RETURN(vap, va_fileid, VTOFDESC(vp)->fd_ix);
 453                 VATTR_RETURN(vap, va_uid, 0);
 454                 VATTR_RETURN(vap, va_gid, 0);
 455                 VATTR_RETURN(vap, va_fsid, vp->v_mount->mnt_vfsstat.f_fsid.val[0]);
 456                 VATTR_RETURN(vap, va_iosize, DEV_BSIZE);
 457                 ts.tv_sec = boottime_sec();
 458                 ts.tv_nsec = 0;
 459                 VATTR_RETURN(vap, va_access_time, ts);
 460                 VATTR_RETURN(vap, va_modify_time, ts);
 461                 VATTR_RETURN(vap, va_change_time, ts);
 462                 VATTR_RETURN(vap, va_gen, 0);
 463                 VATTR_RETURN(vap, va_flags, 0);
 464                 VATTR_RETURN(vap, va_rdev, 0);
 465                 VATTR_RETURN(vap, va_acl, NULL);
 466
 467                 switch (VTOFDESC(vp)->fd_type) {
 468                 case Flink:
 469                         VATTR_RETURN(vap, va_mode, S_IRUSR|S_IRGRP|S_IROTH);
 470                         VATTR_RETURN(vap, va_type, VLNK);       /* not strictly required */
 471                         VATTR_RETURN(vap, va_nlink, 1);
 472                         VATTR_RETURN(vap, va_data_size, strlen(VTOFDESC(vp)->fd_link));
 473                         break;
 474
 475                 default:
 476                         VATTR_RETURN(vap, va_mode, S_IRUSR|S_IXUSR|S_IRGRP|S_IXGRP|S_IROTH|S_IXOTH);
 477                         VATTR_RETURN(vap, va_type, VDIR);
 478                         VATTR_RETURN(vap, va_nlink, 2);
 479                         VATTR_RETURN(vap, va_data_size, DEV_BSIZE);
 480                         break;
 481                 }
 482                 break;
 483
 484         case Fdesc:
 485                 fd = VTOFDESC(vp)->fd_fd;
 486                 error = fdesc_attr(fd, vap, ap->a_context);
 487                 break;
 488
 489         default:
 490                 return (EBADF);
 491                 break;
 492         }
 493
 494         if (error == 0) {
 495                 vp->v_type = vap->va_type;
 496         }
 497
 498         return (error);
 499 }
 500
 501 int
 502 fdesc_setattr(struct vnop_setattr_args *ap)
 503 {
 504         struct fileproc *fp;
 505         unsigned fd;
 506         int error;
 507         struct proc * p = vfs_context_proc(ap->a_context);
 508
 509         /*
 510          * Can't mess with the root vnode
 511          */
 512         switch (VTOFDESC(ap->a_vp)->fd_type) {
 513         case Fdesc:
 514                 break;
 515
 516         default:
 517                 return (EACCES);
 518         }
 519
 520         fd = VTOFDESC(ap->a_vp)->fd_fd;
 521         if ((error = fp_lookup(vfs_context_proc(ap->a_context), fd, &fp, 0)))
 522                 return (error);
 523
 524         /*
 525          * Can setattr the underlying vnode, but not sockets!
 526          */
 527         switch (fp->f_fglob->fg_type) {
 528         case DTYPE_VNODE:
 529         {
 530                 if ((error = vnode_getwithref((struct vnode *) fp->f_fglob->fg_data)) != 0)
 531                         break;
 532                 error = vnode_setattr((struct vnode *) fp->f_fglob->fg_data, ap->a_vap, ap->a_context);
 533                 (void)vnode_put((struct vnode *) fp->f_fglob->fg_data);
 534                 break;
 535         }
 536
 537         case DTYPE_SOCKET:
 538         case DTYPE_PIPE:
 539                 error = 0;
 540                 break;
 541
 542         default:
 543                 kprintf("fp->f_fglob->fg_type = %d\n", fp->f_fglob->fg_type);
 544         error = EBADF;
 545                 break;
 546         }
 547
 548         fp_drop(p, fd, fp, 0);
 549         return (error);
 550 }
 551
 552 #define UIO_MX 16
 553
 554 static struct dirtmp {
 555         u_long d_fileno;
 556         u_short d_reclen;
 557         u_short d_namlen;
 558         char d_name[8];
 559 } rootent[] = {
 560         { FD_DEVFD, UIO_MX, 2, "fd" },
 561         { FD_STDIN, UIO_MX, 5, "stdin" },
 562         { FD_STDOUT, UIO_MX, 6, "stdout" },
 563         { FD_STDERR, UIO_MX, 6, "stderr" },
 564         { 0, 0, 0, "" }
 565 };
 566
 567 int
 568 fdesc_readdir(struct vnop_readdir_args *ap)
 569 {
 570         struct uio *uio = ap->a_uio;
 571         struct proc *p = current_proc();
 572         int i, error;
 573
 574         /*
 575          * We don't allow exporting fdesc mounts, and currently local
 576          * requests do not need cookies.
 577          */
 578         if (ap->a_flags & (VNODE_READDIR_EXTENDED | VNODE_READDIR_REQSEEKOFF))
 579                 return (EINVAL);
 580
 581         switch (VTOFDESC(ap->a_vp)->fd_type) {
 582         case Fdesc:
 583                 return (ENOTDIR);
 584
 585         default:
 586                 break;
 587         }
 588
 589         if (VTOFDESC(ap->a_vp)->fd_type == Froot) {
 590                 struct dirent d;
 591                 struct dirent *dp = &d;
 592                 struct dirtmp *dt;
 593                 int fd;
 594
 595                 i = uio->uio_offset / UIO_MX;
 596                 error = 0;
 597
 598                 while (uio_resid(uio) > 0) {
 599                         dt = &rootent[i];
 600                         if (dt->d_fileno == 0) {
 601                                 /**eofflagp = 1;*/
 602                                 break;
 603                         }
 604                         i++;
 605
 606                         switch (dt->d_fileno) {
 607                         case FD_STDIN:
 608                         case FD_STDOUT:
 609                         case FD_STDERR:
 610                                 fd = dt->d_fileno - FD_STDIN;
 611                                 if (fd >= p->p_fd->fd_nfiles)
 612                                         continue;
 613                                 if (*fdfile(p, fd) == NULL &&
 614                                                 !(*fdflags(p, fd) &
 615                                                         UF_RESERVED))
 616                                         continue;
 617                                 break;
 618                         }
 619                         bzero((caddr_t) dp, UIO_MX);
 620                         dp->d_fileno = dt->d_fileno;
 621                         dp->d_namlen = dt->d_namlen;
 622                         dp->d_type = DT_UNKNOWN;
 623                         dp->d_reclen = dt->d_reclen;
 624                         bcopy(dt->d_name, dp->d_name, dp->d_namlen+1);
 625                         error = uiomove((caddr_t) dp, UIO_MX, uio);
 626                         if (error)
 627                                 break;
 628                 }
 629                 uio->uio_offset = i * UIO_MX;
 630                 return (error);
 631         }
 632
 633         i = uio->uio_offset / UIO_MX;
 634         error = 0;
 635         while (uio_resid(uio) > 0) {
 636                 if (i >= p->p_fd->fd_nfiles)
 637                         break;
 638
 639                 if (*fdfile(p, i) != NULL && !(*fdflags(p, i) & UF_RESERVED)) {
 640                         struct dirent d;
 641                         struct dirent *dp = &d;
 642
 643                         bzero((caddr_t) dp, UIO_MX);
 644
 645                         dp->d_namlen = snprintf(dp->d_name, sizeof(dp->d_name),
 646                                                 "%d", i);
 647                         dp->d_reclen = UIO_MX;
 648                         dp->d_type = DT_UNKNOWN;
 649                         dp->d_fileno = i + FD_STDIN;
 650                         /*
 651                          * And ship to userland
 652                          */
 653                         error = uiomove((caddr_t) dp, UIO_MX, uio);
 654                         if (error)
 655                                 break;
 656                 }
 657                 i++;
 658         }
 659
 660         uio->uio_offset = i * UIO_MX;
 661         return (error);
 662 }
 663
 664 int
 665 fdesc_readlink(struct vnop_readlink_args *ap)
 666 {
 667         struct vnode *vp = ap->a_vp;
 668         int error;
 669
 670         if (vp->v_type != VLNK)
 671                 return (EPERM);
 672
 673         if (VTOFDESC(vp)->fd_type == Flink) {
 674                 const char *ln = VTOFDESC(vp)->fd_link;
 675                 error = uiomove(ln, strlen(ln), ap->a_uio);
 676         } else {
 677                 error = ENOTSUP;
 678         }
 679
 680         return (error);
 681 }
 682
 683 int
 684 fdesc_read(__unused struct vnop_read_args *ap)
 685 {
 686
 687         return (ENOTSUP);
 688 }
 689
 690 int
 691 fdesc_write(__unused struct vnop_write_args *ap)
 692 {
 693         return (ENOTSUP);
 694 }
 695
 696 int
 697 fdesc_ioctl(__unused struct vnop_ioctl_args *ap)
 698 {
 699         return (ENOTSUP);
 700 }
 701
 702 int
 703 fdesc_select(__unused struct vnop_select_args *ap)
 704 {
 705         return (ENOTSUP);
 706 }
 707
 708 int
 709 fdesc_inactive(struct vnop_inactive_args *ap)
 710 {
 711         struct vnode *vp = ap->a_vp;
 712
 713         /*
 714          * Clear out the v_type field to avoid
 715          * nasty things happening in vgone().
 716          */
 717         vp->v_type = VNON;
 718         return (0);
 719 }
 720
 721 int
 722 fdesc_reclaim(struct vnop_reclaim_args *ap)
 723 {
 724         struct vnode *vp = ap->a_vp;
 725         struct fdescnode *fd = VTOFDESC(vp);
 726
 727         LIST_REMOVE(fd, fd_hash);
 728         FREE(vp->v_data, M_TEMP);
 729         vp->v_data = NULL;
 730
 731         return (0);
 732 }
 733
 734 /*
 735  * Return POSIX pathconf information applicable to special devices.
 736  */
 737 int
 738 fdesc_pathconf(struct vnop_pathconf_args *ap)
 739 {
 740
 741         switch (ap->a_name) {
 742         case _PC_LINK_MAX:
 743                 *ap->a_retval = LINK_MAX;
 744                 return (0);
 745         case _PC_MAX_CANON:
 746                 *ap->a_retval = MAX_CANON;
 747                 return (0);
 748         case _PC_MAX_INPUT:
 749                 *ap->a_retval = MAX_INPUT;
 750                 return (0);
 751         case _PC_PIPE_BUF:
 752                 *ap->a_retval = PIPE_BUF;
 753                 return (0);
 754         case _PC_CHOWN_RESTRICTED:
 755                 *ap->a_retval = 200112;         /* _POSIX_CHOWN_RESTRICTED */
 756                 return (0);
 757         case _PC_VDISABLE:
 758                 *ap->a_retval = _POSIX_VDISABLE;
 759                 return (0);
 760         default:
 761                 return (EINVAL);
 762         }
 763         /* NOTREACHED */
 764 }
 765
 766 /*
 767  * /dev/fd "should never get here" operation
 768  */
 769 int
 770 fdesc_badop(void)
 771 {
 772
 773         return (ENOTSUP);
 774         /* NOTREACHED */
 775 }
 776
 777 #define VOPFUNC int (*)(void *)
 778
 779 #define fdesc_create (int (*) (struct  vnop_create_args *))eopnotsupp
 780 #define fdesc_mknod (int (*) (struct  vnop_mknod_args *))eopnotsupp
 781 #define fdesc_close (int (*) (struct  vnop_close_args *))nullop
 782 #define fdesc_access (int (*) (struct  vnop_access_args *))nullop
 783 #define fdesc_mmap (int (*) (struct  vnop_mmap_args *))eopnotsupp
 784 #define fdesc_revoke nop_revoke
 785 #define fdesc_fsync (int (*) (struct  vnop_fsync_args *))nullop
 786 #define fdesc_remove (int (*) (struct  vnop_remove_args *))eopnotsupp
 787 #define fdesc_link (int (*) (struct  vnop_link_args *))eopnotsupp
 788 #define fdesc_rename (int (*) (struct  vnop_rename_args *))eopnotsupp
 789 #define fdesc_mkdir (int (*) (struct  vnop_mkdir_args *))eopnotsupp
 790 #define fdesc_rmdir (int (*) (struct  vnop_rmdir_args *))eopnotsupp
 791 #define fdesc_symlink (int (*) (struct vnop_symlink_args *))eopnotsupp
 792 #define fdesc_strategy (int (*) (struct  vnop_strategy_args *))fdesc_badop
 793 #define fdesc_advlock (int (*) (struct vnop_advlock_args *))eopnotsupp
 794 #define fdesc_bwrite (int (*) (struct  vnop_bwrite_args *))eopnotsupp
 795 #define fdesc_blktooff (int (*) (struct  vnop_blktooff_args *))eopnotsupp
 796 #define fdesc_offtoblk (int (*) (struct  vnop_offtoblk_args *))eopnotsupp
 797 #define fdesc_blockmap (int (*) (struct  vnop_blockmap_args *))eopnotsupp
 798
 799 int (**fdesc_vnodeop_p)(void *);
 800 struct vnodeopv_entry_desc fdesc_vnodeop_entries[] = {
 801         { &vnop_default_desc, (VOPFUNC)vn_default_error },
 802         { &vnop_lookup_desc, (VOPFUNC)fdesc_lookup },   /* lookup */
 803         { &vnop_create_desc, (VOPFUNC)fdesc_create },   /* create */
 804         { &vnop_mknod_desc, (VOPFUNC)fdesc_mknod },     /* mknod */
 805         { &vnop_open_desc, (VOPFUNC)fdesc_open },       /* open */
 806         { &vnop_close_desc, (VOPFUNC)fdesc_close },     /* close */
 807         { &vnop_access_desc, (VOPFUNC)fdesc_access },   /* access */
 808         { &vnop_getattr_desc, (VOPFUNC)fdesc_getattr }, /* getattr */
 809         { &vnop_setattr_desc, (VOPFUNC)fdesc_setattr }, /* setattr */
 810         { &vnop_read_desc, (VOPFUNC)fdesc_read },       /* read */
 811         { &vnop_write_desc, (VOPFUNC)fdesc_write },     /* write */
 812         { &vnop_ioctl_desc, (VOPFUNC)fdesc_ioctl },     /* ioctl */
 813         { &vnop_select_desc, (VOPFUNC)fdesc_select },   /* select */
 814         { &vnop_revoke_desc, (VOPFUNC)fdesc_revoke },   /* revoke */
 815         { &vnop_mmap_desc, (VOPFUNC)fdesc_mmap },       /* mmap */
 816         { &vnop_fsync_desc, (VOPFUNC)fdesc_fsync },     /* fsync */
 817         { &vnop_remove_desc, (VOPFUNC)fdesc_remove },   /* remove */
 818         { &vnop_link_desc, (VOPFUNC)fdesc_link },       /* link */
 819         { &vnop_rename_desc, (VOPFUNC)fdesc_rename },   /* rename */
 820         { &vnop_mkdir_desc, (VOPFUNC)fdesc_mkdir },     /* mkdir */
 821         { &vnop_rmdir_desc, (VOPFUNC)fdesc_rmdir },     /* rmdir */
 822         { &vnop_symlink_desc, (VOPFUNC)fdesc_symlink }, /* symlink */
 823         { &vnop_readdir_desc, (VOPFUNC)fdesc_readdir }, /* readdir */
 824         { &vnop_readlink_desc, (VOPFUNC)fdesc_readlink },/* readlink */
 825         { &vnop_inactive_desc, (VOPFUNC)fdesc_inactive },/* inactive */
 826         { &vnop_reclaim_desc, (VOPFUNC)fdesc_reclaim }, /* reclaim */
 827         { &vnop_strategy_desc, (VOPFUNC)fdesc_strategy },       /* strategy */
 828         { &vnop_pathconf_desc, (VOPFUNC)fdesc_pathconf },       /* pathconf */
 829         { &vnop_advlock_desc, (VOPFUNC)fdesc_advlock }, /* advlock */
 830         { &vnop_bwrite_desc, (VOPFUNC)fdesc_bwrite },   /* bwrite */
 831         { &vnop_pagein_desc, (VOPFUNC)err_pagein },     /* pagein */
 832         { &vnop_pageout_desc, (VOPFUNC)err_pageout },   /* pageout */
 833         { &vnop_copyfile_desc, (VOPFUNC)err_copyfile }, /* Copyfile */
 834         { &vnop_blktooff_desc, (VOPFUNC)fdesc_blktooff },       /* blktooff */
 835         { &vnop_blktooff_desc, (VOPFUNC)fdesc_offtoblk },       /* offtoblk */
 836         { &vnop_blockmap_desc, (VOPFUNC)fdesc_blockmap },       /* blockmap */
 837         { (struct vnodeop_desc*)NULL, (VOPFUNC)NULL }
 838 };
 839 struct vnodeopv_desc fdesc_vnodeop_opv_desc =
 840         { &fdesc_vnodeop_p, fdesc_vnodeop_entries };