The Design and Implementation of the FreeBSD Operating System, Second Edition
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FreeBSD/Linux Kernel Cross Reference
sys/fs/fdescfs/fdesc_vnops.c

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    1 /*-
    2  * SPDX-License-Identifier: BSD-3-Clause
    3  *
    4  * Copyright (c) 1992, 1993
    5  *      The Regents of the University of California.  All rights reserved.
    6  *
    7  * This code is derived from software donated to Berkeley by
    8  * Jan-Simon Pendry.
    9  *
   10  * Redistribution and use in source and binary forms, with or without
   11  * modification, are permitted provided that the following conditions
   12  * are met:
   13  * 1. Redistributions of source code must retain the above copyright
   14  *    notice, this list of conditions and the following disclaimer.
   15  * 2. Redistributions in binary form must reproduce the above copyright
   16  *    notice, this list of conditions and the following disclaimer in the
   17  *    documentation and/or other materials provided with the distribution.
   18  * 3. Neither the name of the University nor the names of its contributors
   19  *    may be used to endorse or promote products derived from this software
   20  *    without specific prior written permission.
   21  *
   22  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
   23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
   25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
   26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
   27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
   28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
   29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
   30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
   31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
   32  * SUCH DAMAGE.
   33  *
   34  *      @(#)fdesc_vnops.c       8.9 (Berkeley) 1/21/94
   35  *
   36  * $FreeBSD$
   37  */
   38 
   39 /*
   40  * /dev/fd Filesystem
   41  */
   42 
   43 #include <sys/param.h>
   44 #include <sys/systm.h>
   45 #include <sys/capsicum.h>
   46 #include <sys/conf.h>
   47 #include <sys/dirent.h>
   48 #include <sys/filedesc.h>
   49 #include <sys/kernel.h> /* boottime */
   50 #include <sys/lock.h>
   51 #include <sys/mutex.h>
   52 #include <sys/malloc.h>
   53 #include <sys/file.h>   /* Must come after sys/malloc.h */
   54 #include <sys/mount.h>
   55 #include <sys/namei.h>
   56 #include <sys/proc.h>
   57 #include <sys/stat.h>
   58 #include <sys/syscallsubr.h>
   59 #include <sys/unistd.h>
   60 #include <sys/vnode.h>
   61 
   62 #include <fs/fdescfs/fdesc.h>
   63 
   64 #define NFDCACHE 4
   65 #define FD_NHASH(ix) \
   66         (&fdhashtbl[(ix) & fdhash])
   67 static LIST_HEAD(fdhashhead, fdescnode) *fdhashtbl;
   68 static u_long fdhash;
   69 
   70 struct mtx fdesc_hashmtx;
   71 
   72 static vop_getattr_t    fdesc_getattr;
   73 static vop_lookup_t     fdesc_lookup;
   74 static vop_open_t       fdesc_open;
   75 static vop_pathconf_t   fdesc_pathconf;
   76 static vop_readdir_t    fdesc_readdir;
   77 static vop_readlink_t   fdesc_readlink;
   78 static vop_reclaim_t    fdesc_reclaim;
   79 static vop_setattr_t    fdesc_setattr;
   80 
   81 static struct vop_vector fdesc_vnodeops = {
   82         .vop_default =          &default_vnodeops,
   83 
   84         .vop_access =           VOP_NULL,
   85         .vop_getattr =          fdesc_getattr,
   86         .vop_lookup =           fdesc_lookup,
   87         .vop_open =             fdesc_open,
   88         .vop_pathconf =         fdesc_pathconf,
   89         .vop_readdir =          fdesc_readdir,
   90         .vop_readlink =         fdesc_readlink,
   91         .vop_reclaim =          fdesc_reclaim,
   92         .vop_setattr =          fdesc_setattr,
   93 };
   94 
   95 static void fdesc_insmntque_dtr(struct vnode *, void *);
   96 static void fdesc_remove_entry(struct fdescnode *);
   97 
   98 /*
   99  * Initialise cache headers
  100  */
  101 int
  102 fdesc_init(struct vfsconf *vfsp)
  103 {
  104 
  105         mtx_init(&fdesc_hashmtx, "fdescfs_hash", NULL, MTX_DEF);
  106         fdhashtbl = hashinit(NFDCACHE, M_CACHE, &fdhash);
  107         return (0);
  108 }
  109 
  110 /*
  111  * Uninit ready for unload.
  112  */
  113 int
  114 fdesc_uninit(struct vfsconf *vfsp)
  115 {
  116 
  117         hashdestroy(fdhashtbl, M_CACHE, fdhash);
  118         mtx_destroy(&fdesc_hashmtx);
  119         return (0);
  120 }
  121 
  122 /*
  123  * If allocating vnode fails, call this.
  124  */
  125 static void
  126 fdesc_insmntque_dtr(struct vnode *vp, void *arg)
  127 {
  128 
  129         vgone(vp);
  130         vput(vp);
  131 }
  132 
  133 /*
  134  * Remove an entry from the hash if it exists.
  135  */
  136 static void
  137 fdesc_remove_entry(struct fdescnode *fd)
  138 {
  139         struct fdhashhead *fc;
  140         struct fdescnode *fd2;
  141 
  142         fc = FD_NHASH(fd->fd_ix);
  143         mtx_lock(&fdesc_hashmtx);
  144         LIST_FOREACH(fd2, fc, fd_hash) {
  145                 if (fd == fd2) {
  146                         LIST_REMOVE(fd, fd_hash);
  147                         break;
  148                 }
  149         }
  150         mtx_unlock(&fdesc_hashmtx);
  151 }
  152 
  153 int
  154 fdesc_allocvp(fdntype ftype, unsigned fd_fd, int ix, struct mount *mp,
  155     struct vnode **vpp)
  156 {
  157         struct fdescmount *fmp;
  158         struct fdhashhead *fc;
  159         struct fdescnode *fd, *fd2;
  160         struct vnode *vp, *vp2;
  161         struct thread *td;
  162         int error;
  163 
  164         td = curthread;
  165         fc = FD_NHASH(ix);
  166 loop:
  167         mtx_lock(&fdesc_hashmtx);
  168         /*
  169          * If a forced unmount is progressing, we need to drop it. The flags are
  170          * protected by the hashmtx.
  171          */
  172         fmp = mp->mnt_data;
  173         if (fmp == NULL || fmp->flags & FMNT_UNMOUNTF) {
  174                 mtx_unlock(&fdesc_hashmtx);
  175                 return (-1);
  176         }
  177 
  178         LIST_FOREACH(fd, fc, fd_hash) {
  179                 if (fd->fd_ix == ix && fd->fd_vnode->v_mount == mp) {
  180                         /* Get reference to vnode in case it's being free'd */
  181                         vp = fd->fd_vnode;
  182                         VI_LOCK(vp);
  183                         mtx_unlock(&fdesc_hashmtx);
  184                         if (vget(vp, LK_EXCLUSIVE | LK_INTERLOCK, td))
  185                                 goto loop;
  186                         *vpp = vp;
  187                         return (0);
  188                 }
  189         }
  190         mtx_unlock(&fdesc_hashmtx);
  191 
  192         fd = malloc(sizeof(struct fdescnode), M_TEMP, M_WAITOK);
  193 
  194         error = getnewvnode("fdescfs", mp, &fdesc_vnodeops, &vp);
  195         if (error) {
  196                 free(fd, M_TEMP);
  197                 return (error);
  198         }
  199         vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
  200         vp->v_data = fd;
  201         fd->fd_vnode = vp;
  202         fd->fd_type = ftype;
  203         fd->fd_fd = fd_fd;
  204         fd->fd_ix = ix;
  205         if (ftype == Fdesc && fmp->flags & FMNT_LINRDLNKF)
  206                 vp->v_vflag |= VV_READLINK;
  207         error = insmntque1(vp, mp, fdesc_insmntque_dtr, NULL);
  208         if (error != 0) {
  209                 *vpp = NULLVP;
  210                 return (error);
  211         }
  212 
  213         /* Make sure that someone didn't beat us when inserting the vnode. */
  214         mtx_lock(&fdesc_hashmtx);
  215         /*
  216          * If a forced unmount is progressing, we need to drop it. The flags are
  217          * protected by the hashmtx.
  218          */
  219         fmp = mp->mnt_data;
  220         if (fmp == NULL || fmp->flags & FMNT_UNMOUNTF) {
  221                 mtx_unlock(&fdesc_hashmtx);
  222                 vgone(vp);
  223                 vput(vp);
  224                 *vpp = NULLVP;
  225                 return (-1);
  226         }
  227 
  228         LIST_FOREACH(fd2, fc, fd_hash) {
  229                 if (fd2->fd_ix == ix && fd2->fd_vnode->v_mount == mp) {
  230                         /* Get reference to vnode in case it's being free'd */
  231                         vp2 = fd2->fd_vnode;
  232                         VI_LOCK(vp2);
  233                         mtx_unlock(&fdesc_hashmtx);
  234                         error = vget(vp2, LK_EXCLUSIVE | LK_INTERLOCK, td);
  235                         /* Someone beat us, dec use count and wait for reclaim */
  236                         vgone(vp);
  237                         vput(vp);
  238                         /* If we didn't get it, return no vnode. */
  239                         if (error)
  240                                 vp2 = NULLVP;
  241                         *vpp = vp2;
  242                         return (error);
  243                 }
  244         }
  245 
  246         /* If we came here, we can insert it safely. */
  247         LIST_INSERT_HEAD(fc, fd, fd_hash);
  248         mtx_unlock(&fdesc_hashmtx);
  249         *vpp = vp;
  250         return (0);
  251 }
  252 
  253 struct fdesc_get_ino_args {
  254         fdntype ftype;
  255         unsigned fd_fd;
  256         int ix;
  257         struct file *fp;
  258         struct thread *td;
  259 };
  260 
  261 static int
  262 fdesc_get_ino_alloc(struct mount *mp, void *arg, int lkflags,
  263     struct vnode **rvp)
  264 {
  265         struct fdesc_get_ino_args *a;
  266         int error;
  267 
  268         a = arg;
  269         error = fdesc_allocvp(a->ftype, a->fd_fd, a->ix, mp, rvp);
  270         fdrop(a->fp, a->td);
  271         return (error);
  272 }
  273 
  274 
  275 /*
  276  * vp is the current namei directory
  277  * ndp is the name to locate in that directory...
  278  */
  279 static int
  280 fdesc_lookup(struct vop_lookup_args *ap)
  281 {
  282         struct vnode **vpp = ap->a_vpp;
  283         struct vnode *dvp = ap->a_dvp;
  284         struct componentname *cnp = ap->a_cnp;
  285         char *pname = cnp->cn_nameptr;
  286         struct thread *td = cnp->cn_thread;
  287         struct file *fp;
  288         struct fdesc_get_ino_args arg;
  289         int nlen = cnp->cn_namelen;
  290         u_int fd, fd1;
  291         int error;
  292         struct vnode *fvp;
  293 
  294         if ((cnp->cn_flags & ISLASTCN) &&
  295             (cnp->cn_nameiop == DELETE || cnp->cn_nameiop == RENAME)) {
  296                 error = EROFS;
  297                 goto bad;
  298         }
  299 
  300         if (cnp->cn_namelen == 1 && *pname == '.') {
  301                 *vpp = dvp;
  302                 VREF(dvp);
  303                 return (0);
  304         }
  305 
  306         if (VTOFDESC(dvp)->fd_type != Froot) {
  307                 error = ENOTDIR;
  308                 goto bad;
  309         }
  310 
  311         fd = 0;
  312         /* the only time a leading 0 is acceptable is if it's "" */
  313         if (*pname == '' && nlen != 1) {
  314                 error = ENOENT;
  315                 goto bad;
  316         }
  317         while (nlen--) {
  318                 if (*pname < '' || *pname > '9') {
  319                         error = ENOENT;
  320                         goto bad;
  321                 }
  322                 fd1 = 10 * fd + *pname++ - '';
  323                 if (fd1 < fd) {
  324                         error = ENOENT;
  325                         goto bad;
  326                 }
  327                 fd = fd1;
  328         }
  329 
  330         /*
  331          * No rights to check since 'fp' isn't actually used.
  332          */
  333         if ((error = fget(td, fd, &cap_no_rights, &fp)) != 0)
  334                 goto bad;
  335 
  336         /* Check if we're looking up ourselves. */
  337         if (VTOFDESC(dvp)->fd_ix == FD_DESC + fd) {
  338                 /*
  339                  * In case we're holding the last reference to the file, the dvp
  340                  * will be re-acquired.
  341                  */
  342                 vhold(dvp);
  343                 VOP_UNLOCK(dvp, 0);
  344                 fdrop(fp, td);
  345 
  346                 /* Re-aquire the lock afterwards. */
  347                 vn_lock(dvp, LK_RETRY | LK_EXCLUSIVE);
  348                 vdrop(dvp);
  349                 fvp = dvp;
  350                 if ((dvp->v_iflag & VI_DOOMED) != 0)
  351                         error = ENOENT;
  352         } else {
  353                 /*
  354                  * Unlock our root node (dvp) when doing this, since we might
  355                  * deadlock since the vnode might be locked by another thread
  356                  * and the root vnode lock will be obtained afterwards (in case
  357                  * we're looking up the fd of the root vnode), which will be the
  358                  * opposite lock order. Vhold the root vnode first so we don't
  359                  * lose it.
  360                  */
  361                 arg.ftype = Fdesc;
  362                 arg.fd_fd = fd;
  363                 arg.ix = FD_DESC + fd;
  364                 arg.fp = fp;
  365                 arg.td = td;
  366                 error = vn_vget_ino_gen(dvp, fdesc_get_ino_alloc, &arg,
  367                     LK_EXCLUSIVE, &fvp);
  368         }
  369 
  370         if (error)
  371                 goto bad;
  372         *vpp = fvp;
  373         return (0);
  374 
  375 bad:
  376         *vpp = NULL;
  377         return (error);
  378 }
  379 
  380 static int
  381 fdesc_open(struct vop_open_args *ap)
  382 {
  383         struct vnode *vp = ap->a_vp;
  384 
  385         if (VTOFDESC(vp)->fd_type == Froot)
  386                 return (0);
  387 
  388         /*
  389          * XXX Kludge: set td->td_proc->p_dupfd to contain the value of the file
  390          * descriptor being sought for duplication. The error return ensures
  391          * that the vnode for this device will be released by vn_open. Open
  392          * will detect this special error and take the actions in dupfdopen.
  393          * Other callers of vn_open or VOP_OPEN will simply report the
  394          * error.
  395          */
  396         ap->a_td->td_dupfd = VTOFDESC(vp)->fd_fd;       /* XXX */
  397         return (ENODEV);
  398 }
  399 
  400 static int
  401 fdesc_pathconf(struct vop_pathconf_args *ap)
  402 {
  403         struct vnode *vp = ap->a_vp;
  404         int error;
  405 
  406         switch (ap->a_name) {
  407         case _PC_NAME_MAX:
  408                 *ap->a_retval = NAME_MAX;
  409                 return (0);
  410         case _PC_LINK_MAX:
  411                 if (VTOFDESC(vp)->fd_type == Froot)
  412                         *ap->a_retval = 2;
  413                 else
  414                         *ap->a_retval = 1;
  415                 return (0);
  416         default:
  417                 if (VTOFDESC(vp)->fd_type == Froot)
  418                         return (vop_stdpathconf(ap));
  419                 vref(vp);
  420                 VOP_UNLOCK(vp, 0);
  421                 error = kern_fpathconf(curthread, VTOFDESC(vp)->fd_fd,
  422                     ap->a_name, ap->a_retval);
  423                 vn_lock(vp, LK_SHARED | LK_RETRY);
  424                 vunref(vp);
  425                 return (error);
  426         }
  427 }
  428 
  429 static int
  430 fdesc_getattr(struct vop_getattr_args *ap)
  431 {
  432         struct vnode *vp = ap->a_vp;
  433         struct vattr *vap = ap->a_vap;
  434         struct timeval boottime;
  435 
  436         getboottime(&boottime);
  437         vap->va_mode = S_IRUSR|S_IXUSR|S_IRGRP|S_IXGRP|S_IROTH|S_IXOTH;
  438         vap->va_fileid = VTOFDESC(vp)->fd_ix;
  439         vap->va_uid = 0;
  440         vap->va_gid = 0;
  441         vap->va_blocksize = DEV_BSIZE;
  442         vap->va_atime.tv_sec = boottime.tv_sec;
  443         vap->va_atime.tv_nsec = 0;
  444         vap->va_mtime = vap->va_atime;
  445         vap->va_ctime = vap->va_mtime;
  446         vap->va_gen = 0;
  447         vap->va_flags = 0;
  448         vap->va_bytes = 0;
  449         vap->va_filerev = 0;
  450 
  451         switch (VTOFDESC(vp)->fd_type) {
  452         case Froot:
  453                 vap->va_type = VDIR;
  454                 vap->va_nlink = 2;
  455                 vap->va_size = DEV_BSIZE;
  456                 vap->va_rdev = NODEV;
  457                 break;
  458 
  459         case Fdesc:
  460                 vap->va_type = (vp->v_vflag & VV_READLINK) == 0 ? VCHR : VLNK;
  461                 vap->va_nlink = 1;
  462                 vap->va_size = 0;
  463                 vap->va_rdev = makedev(0, vap->va_fileid);
  464                 break;
  465 
  466         default:
  467                 panic("fdesc_getattr");
  468                 break;
  469         }
  470 
  471         vp->v_type = vap->va_type;
  472         return (0);
  473 }
  474 
  475 static int
  476 fdesc_setattr(struct vop_setattr_args *ap)
  477 {
  478         struct vattr *vap = ap->a_vap;
  479         struct vnode *vp;
  480         struct mount *mp;
  481         struct file *fp;
  482         struct thread *td = curthread;
  483         cap_rights_t rights;
  484         unsigned fd;
  485         int error;
  486 
  487         /*
  488          * Can't mess with the root vnode
  489          */
  490         if (VTOFDESC(ap->a_vp)->fd_type == Froot)
  491                 return (EACCES);
  492 
  493         fd = VTOFDESC(ap->a_vp)->fd_fd;
  494 
  495         /*
  496          * Allow setattr where there is an underlying vnode.
  497          */
  498         error = getvnode(td, fd,
  499             cap_rights_init(&rights, CAP_EXTATTR_SET), &fp);
  500         if (error) {
  501                 /*
  502                  * getvnode() returns EINVAL if the file descriptor is not
  503                  * backed by a vnode.  Silently drop all changes except
  504                  * chflags(2) in this case.
  505                  */
  506                 if (error == EINVAL) {
  507                         if (vap->va_flags != VNOVAL)
  508                                 error = EOPNOTSUPP;
  509                         else
  510                                 error = 0;
  511                 }
  512                 return (error);
  513         }
  514         vp = fp->f_vnode;
  515         if ((error = vn_start_write(vp, &mp, V_WAIT | PCATCH)) == 0) {
  516                 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
  517                 error = VOP_SETATTR(vp, ap->a_vap, ap->a_cred);
  518                 VOP_UNLOCK(vp, 0);
  519                 vn_finished_write(mp);
  520         }
  521         fdrop(fp, td);
  522         return (error);
  523 }
  524 
  525 #define UIO_MX _GENERIC_DIRLEN(10) /* number of symbols in INT_MAX printout */
  526 
  527 static int
  528 fdesc_readdir(struct vop_readdir_args *ap)
  529 {
  530         struct fdescmount *fmp;
  531         struct uio *uio = ap->a_uio;
  532         struct filedesc *fdp;
  533         struct dirent d;
  534         struct dirent *dp = &d;
  535         int error, i, off, fcnt;
  536 
  537         if (VTOFDESC(ap->a_vp)->fd_type != Froot)
  538                 panic("fdesc_readdir: not dir");
  539 
  540         fmp = VFSTOFDESC(ap->a_vp->v_mount);
  541         if (ap->a_ncookies != NULL)
  542                 *ap->a_ncookies = 0;
  543 
  544         off = (int)uio->uio_offset;
  545         if (off != uio->uio_offset || off < 0 || (u_int)off % UIO_MX != 0 ||
  546             uio->uio_resid < UIO_MX)
  547                 return (EINVAL);
  548         i = (u_int)off / UIO_MX;
  549         fdp = uio->uio_td->td_proc->p_fd;
  550         error = 0;
  551 
  552         fcnt = i - 2;           /* The first two nodes are `.' and `..' */
  553 
  554         FILEDESC_SLOCK(fdp);
  555         while (i < fdp->fd_nfiles + 2 && uio->uio_resid >= UIO_MX) {
  556                 bzero((caddr_t)dp, UIO_MX);
  557                 switch (i) {
  558                 case 0: /* `.' */
  559                 case 1: /* `..' */
  560                         dp->d_fileno = i + FD_ROOT;
  561                         dp->d_namlen = i + 1;
  562                         dp->d_reclen = UIO_MX;
  563                         bcopy("..", dp->d_name, dp->d_namlen);
  564                         dp->d_type = DT_DIR;
  565                         dirent_terminate(dp);
  566                         break;
  567                 default:
  568                         if (fdp->fd_ofiles[fcnt].fde_file == NULL)
  569                                 break;
  570                         dp->d_namlen = sprintf(dp->d_name, "%d", fcnt);
  571                         dp->d_reclen = UIO_MX;
  572                         dp->d_type = (fmp->flags & FMNT_LINRDLNKF) == 0 ?
  573                             DT_CHR : DT_LNK;
  574                         dp->d_fileno = i + FD_DESC;
  575                         dirent_terminate(dp);
  576                         break;
  577                 }
  578                 /* NOTE: d_off is the offset of the *next* entry. */
  579                 dp->d_off = UIO_MX * (i + 1);
  580                 if (dp->d_namlen != 0) {
  581                         /*
  582                          * And ship to userland
  583                          */
  584                         FILEDESC_SUNLOCK(fdp);
  585                         error = uiomove(dp, UIO_MX, uio);
  586                         if (error)
  587                                 goto done;
  588                         FILEDESC_SLOCK(fdp);
  589                 }
  590                 i++;
  591                 fcnt++;
  592         }
  593         FILEDESC_SUNLOCK(fdp);
  594 
  595 done:
  596         uio->uio_offset = i * UIO_MX;
  597         return (error);
  598 }
  599 
  600 static int
  601 fdesc_reclaim(struct vop_reclaim_args *ap)
  602 {
  603         struct vnode *vp;
  604         struct fdescnode *fd;
  605 
  606         vp = ap->a_vp;
  607         fd = VTOFDESC(vp);
  608         fdesc_remove_entry(fd);
  609         free(vp->v_data, M_TEMP);
  610         vp->v_data = NULL;
  611         return (0);
  612 }
  613 
  614 static int
  615 fdesc_readlink(struct vop_readlink_args *va)
  616 {
  617         struct vnode *vp, *vn;
  618         struct thread *td;
  619         struct uio *uio;
  620         struct file *fp;
  621         char *freepath, *fullpath;
  622         size_t pathlen;
  623         int lockflags, fd_fd;
  624         int error;
  625 
  626         freepath = NULL;
  627         vn = va->a_vp;
  628         if (VTOFDESC(vn)->fd_type != Fdesc)
  629                 panic("fdesc_readlink: not fdescfs link");
  630         fd_fd = ((struct fdescnode *)vn->v_data)->fd_fd;
  631         lockflags = VOP_ISLOCKED(vn);
  632         VOP_UNLOCK(vn, 0);
  633 
  634         td = curthread;
  635         error = fget_cap(td, fd_fd, &cap_no_rights, &fp, NULL);
  636         if (error != 0)
  637                 goto out;
  638 
  639         switch (fp->f_type) {
  640         case DTYPE_VNODE:
  641                 vp = fp->f_vnode;
  642                 error = vn_fullpath(td, vp, &fullpath, &freepath);
  643                 break;
  644         default:
  645                 fullpath = "anon_inode:[unknown]";
  646                 break;
  647         }
  648         if (error == 0) {
  649                 uio = va->a_uio;
  650                 pathlen = strlen(fullpath);
  651                 error = uiomove(fullpath, pathlen, uio);
  652         }
  653         if (freepath != NULL)
  654                 free(freepath, M_TEMP);
  655         fdrop(fp, td);
  656 
  657 out:
  658         vn_lock(vn, lockflags | LK_RETRY);
  659         return (error);
  660 }

Cache object: 2ae7a310af2b01cd522aa49a04b3080c


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