bsd/miscfs/fdesc/fdesc_vfsops.c

   1 /*
   2  * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * Copyright (c) 1999-2003 Apple Computer, Inc.  All Rights Reserved.
   7  *
   8  * This file contains Original Code and/or Modifications of Original Code
   9  * as defined in and that are subject to the Apple Public Source License
  10  * Version 2.0 (the 'License'). You may not use this file except in
  11  * compliance with the License. Please obtain a copy of the License at
  12  * http://www.opensource.apple.com/apsl/ and read it before using this
  13  * file.
  14  *
  15  * The Original Code and all software distributed under the License are
  16  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  17  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  18  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  19  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  20  * Please see the License for the specific language governing rights and
  21  * limitations under the License.
  22  *
  23  * @APPLE_LICENSE_HEADER_END@
  24  */
  25 /* Copyright (c) 1995 NeXT Computer, Inc. All Rights Reserved */
  26 /*
  27  * Copyright (c) 1992, 1993, 1995
  28  *      The Regents of the University of California.  All rights reserved.
  29  *
  30  * This code is derived from software donated to Berkeley by
  31  * Jan-Simon Pendry.
  32  *
  33  * Redistribution and use in source and binary forms, with or without
  34  * modification, are permitted provided that the following conditions
  35  * are met:
  36  * 1. Redistributions of source code must retain the above copyright
  37  *    notice, this list of conditions and the following disclaimer.
  38  * 2. Redistributions in binary form must reproduce the above copyright
  39  *    notice, this list of conditions and the following disclaimer in the
  40  *    documentation and/or other materials provided with the distribution.
  41  * 3. All advertising materials mentioning features or use of this software
  42  *    must display the following acknowledgement:
  43  *      This product includes software developed by the University of
  44  *      California, Berkeley and its contributors.
  45  * 4. Neither the name of the University nor the names of its contributors
  46  *    may be used to endorse or promote products derived from this software
  47  *    without specific prior written permission.
  48  *
  49  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  50  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  51  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  52  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  53  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  54  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  55  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  56  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  57  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  58  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  59  * SUCH DAMAGE.
  60  *
  61  *      @(#)fdesc_vfsops.c      8.10 (Berkeley) 5/14/95
  62  *
  63  */
  64
  65 /*
  66  * /dev/fd Filesystem
  67  */
  68
  69 #include <sys/param.h>
  70 #include <sys/systm.h>
  71 #include <sys/time.h>
  72 #include <sys/types.h>
  73 #include <sys/proc.h>
  74 #include <sys/resourcevar.h>
  75 #include <sys/filedesc.h>
  76 #include <sys/vnode.h>
  77 #include <sys/mount.h>
  78 #include <sys/namei.h>
  79 #include <sys/malloc.h>
  80 #include <miscfs/fdesc/fdesc.h>
  81
  82 /*
  83  * Mount the per-process file descriptors (/dev/fd)
  84  */
  85 int
  86 fdesc_mount(mp, path, data, ndp, p)
  87         struct mount *mp;
  88         char *path;
  89         caddr_t data;
  90         struct nameidata *ndp;
  91         struct proc *p;
  92 {
  93         int error = 0;
  94         u_int size;
  95         struct fdescmount *fmp;
  96         struct vnode *rvp;
  97
  98         /*
  99          * Update is a no-op
 100          */
 101         if (mp->mnt_flag & MNT_UPDATE)
 102                 return (EOPNOTSUPP);
 103
 104         error = fdesc_allocvp(Froot, FD_ROOT, mp, &rvp);
 105         if (error)
 106                 return (error);
 107
 108         MALLOC(fmp, struct fdescmount *, sizeof(struct fdescmount),
 109                                 M_UFSMNT, M_WAITOK);    /* XXX */
 110         rvp->v_type = VDIR;
 111         rvp->v_flag |= VROOT;
 112         fmp->f_root = rvp;
 113         /* XXX -- don't mark as local to work around fts() problems */
 114         /*mp->mnt_flag |= MNT_LOCAL;*/
 115         mp->mnt_data = (qaddr_t) fmp;
 116         vfs_getnewfsid(mp);
 117
 118         (void) copyinstr(path, mp->mnt_stat.f_mntonname, MNAMELEN - 1, &size);
 119         bzero(mp->mnt_stat.f_mntonname + size, MNAMELEN - size);
 120         bzero(mp->mnt_stat.f_mntfromname, MNAMELEN);
 121         bcopy("fdesc", mp->mnt_stat.f_mntfromname, sizeof("fdesc"));
 122         return (0);
 123 }
 124
 125 int
 126 fdesc_start(mp, flags, p)
 127         struct mount *mp;
 128         int flags;
 129         struct proc *p;
 130 {
 131         return (0);
 132 }
 133
 134 int
 135 fdesc_unmount(mp, mntflags, p)
 136         struct mount *mp;
 137         int mntflags;
 138         struct proc *p;
 139 {
 140         int error;
 141         int flags = 0;
 142         int force = 0;
 143         struct vnode *rootvp = VFSTOFDESC(mp)->f_root;
 144
 145         if (mntflags & MNT_FORCE) {
 146                 flags |= FORCECLOSE;
 147                 force = 1;
 148         }
 149
 150         if ( (rootvp->v_usecount > 1) && !force )
 151                 return (EBUSY);
 152         if ( (error = vflush(mp, rootvp, flags)) && !force )
 153                 return (error);
 154
 155         /*
 156          * Release reference on underlying root vnode
 157          */
 158         vrele(rootvp);
 159         /*
 160          * And blow it away for future re-use
 161          */
 162         vgone(rootvp);
 163         /*
 164          * Finally, throw away the fdescmount structure
 165          */
 166         _FREE(mp->mnt_data, M_UFSMNT);  /* XXX */
 167         mp->mnt_data = 0;
 168
 169         return (0);
 170 }
 171
 172 int
 173 fdesc_root(mp, vpp)
 174         struct mount *mp;
 175         struct vnode **vpp;
 176 {
 177         struct proc *p = current_proc();        /* XXX */
 178         struct vnode *vp;
 179
 180         /*
 181          * Return locked reference to root.
 182          */
 183         vp = VFSTOFDESC(mp)->f_root;
 184         VREF(vp);
 185         vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, p);
 186         *vpp = vp;
 187         return (0);
 188 }
 189
 190 int
 191 fdesc_statfs(mp, sbp, p)
 192         struct mount *mp;
 193         struct statfs *sbp;
 194         struct proc *p;
 195 {
 196         struct filedesc *fdp;
 197         int lim;
 198         int i;
 199         int last;
 200         int freefd;
 201
 202         /*
 203          * Compute number of free file descriptors.
 204          * [ Strange results will ensue if the open file
 205          * limit is ever reduced below the current number
 206          * of open files... ]
 207          */
 208         lim = p->p_rlimit[RLIMIT_NOFILE].rlim_cur;
 209         fdp = p->p_fd;
 210         last = min(fdp->fd_nfiles, lim);
 211         freefd = 0;
 212         for (i = fdp->fd_freefile; i < last; i++)
 213                 if (fdp->fd_ofiles[i] == NULL &&
 214                                 !(fdp->fd_ofileflags[i] & UF_RESERVED))
 215                         freefd++;
 216
 217         /*
 218          * Adjust for the fact that the fdesc array may not
 219          * have been fully allocated yet.
 220          */
 221         if (fdp->fd_nfiles < lim)
 222                 freefd += (lim - fdp->fd_nfiles);
 223
 224         sbp->f_flags = 0;
 225         sbp->f_bsize = DEV_BSIZE;
 226         sbp->f_iosize = DEV_BSIZE;
 227         sbp->f_blocks = 2;              /* 1K to keep df happy */
 228         sbp->f_bfree = 0;
 229         sbp->f_bavail = 0;
 230         sbp->f_files = lim + 1;         /* Allow for "." */
 231         sbp->f_ffree = freefd;          /* See comments above */
 232         if (sbp != &mp->mnt_stat) {
 233                 sbp->f_type = mp->mnt_vfc->vfc_typenum;
 234                 bcopy(&mp->mnt_stat.f_fsid, &sbp->f_fsid, sizeof(sbp->f_fsid));
 235                 bcopy(mp->mnt_stat.f_mntonname, sbp->f_mntonname, MNAMELEN);
 236                 bcopy(mp->mnt_stat.f_mntfromname, sbp->f_mntfromname, MNAMELEN);
 237         }
 238         return (0);
 239 }
 240
 241 int
 242 fdesc_sync(mp, waitfor)
 243         struct mount *mp;
 244         int waitfor;
 245 {
 246
 247         return (0);
 248 }
 249
 250 #define fdesc_fhtovp ((int (*) __P((struct mount *, struct fid *, \
 251             struct mbuf *, struct vnode **, int *, struct ucred **)))eopnotsupp)
 252 #define fdesc_quotactl ((int (*) __P((struct mount *, int, uid_t, caddr_t, \
 253             struct proc *)))eopnotsupp)
 254 #define fdesc_sysctl ((int (*) __P((int *, u_int, void *, size_t *, void *, \
 255             size_t, struct proc *)))eopnotsupp)
 256 #define fdesc_vget ((int (*) __P((struct mount *, ino_t, struct vnode **))) \
 257             eopnotsupp)
 258 #define fdesc_vptofh ((int (*) __P((struct vnode *, struct fid *)))eopnotsupp)
 259
 260 struct vfsops fdesc_vfsops = {
 261         fdesc_mount,
 262         fdesc_start,
 263         fdesc_unmount,
 264         fdesc_root,
 265         fdesc_quotactl,
 266         fdesc_statfs,
 267         fdesc_sync,
 268         fdesc_vget,
 269         fdesc_fhtovp,
 270         fdesc_vptofh,
 271         fdesc_init,
 272         fdesc_sysctl,
 273 };