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  * The contents of this file constitute Original Code as defined in and
   7  * are subject to the Apple Public Source License Version 1.1 (the
   8  * "License").  You may not use this file except in compliance with the
   9  * License.  Please obtain a copy of the License at
  10  * http://www.apple.com/publicsource and read it before using this file.
  11  *
  12  * This Original Code and all software distributed under the License are
  13  * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  14  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  15  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  16  * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
  17  * License for the specific language governing rights and limitations
  18  * under the License.
  19  *
  20  * @APPLE_LICENSE_HEADER_END@
  21  */
  22 /* Copyright (c) 1995 NeXT Computer, Inc. All Rights Reserved */
  23 /*
  24  * Copyright (c) 1992, 1993, 1995
  25  *      The Regents of the University of California.  All rights reserved.
  26  *
  27  * This code is derived from software donated to Berkeley by
  28  * Jan-Simon Pendry.
  29  *
  30  * Redistribution and use in source and binary forms, with or without
  31  * modification, are permitted provided that the following conditions
  32  * are met:
  33  * 1. Redistributions of source code must retain the above copyright
  34  *    notice, this list of conditions and the following disclaimer.
  35  * 2. Redistributions in binary form must reproduce the above copyright
  36  *    notice, this list of conditions and the following disclaimer in the
  37  *    documentation and/or other materials provided with the distribution.
  38  * 3. All advertising materials mentioning features or use of this software
  39  *    must display the following acknowledgement:
  40  *      This product includes software developed by the University of
  41  *      California, Berkeley and its contributors.
  42  * 4. Neither the name of the University nor the names of its contributors
  43  *    may be used to endorse or promote products derived from this software
  44  *    without specific prior written permission.
  45  *
  46  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  47  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  48  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  49  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  50  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  51  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  52  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  53  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  54  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  55  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  56  * SUCH DAMAGE.
  57  *
  58  *      @(#)fdesc_vfsops.c      8.10 (Berkeley) 5/14/95
  59  *
  60  */
  61
  62 /*
  63  * /dev/fd Filesystem
  64  */
  65
  66 #include <sys/param.h>
  67 #include <sys/systm.h>
  68 #include <sys/time.h>
  69 #include <sys/types.h>
  70 #include <sys/proc.h>
  71 #include <sys/resourcevar.h>
  72 #include <sys/filedesc.h>
  73 #include <sys/vnode.h>
  74 #include <sys/mount.h>
  75 #include <sys/namei.h>
  76 #include <sys/malloc.h>
  77 #include <miscfs/fdesc/fdesc.h>
  78
  79 /*
  80  * Mount the per-process file descriptors (/dev/fd)
  81  */
  82 int
  83 fdesc_mount(mp, path, data, ndp, p)
  84         struct mount *mp;
  85         char *path;
  86         caddr_t data;
  87         struct nameidata *ndp;
  88         struct proc *p;
  89 {
  90         int error = 0;
  91         size_t size;
  92         struct fdescmount *fmp;
  93         struct vnode *rvp;
  94
  95         /*
  96          * Update is a no-op
  97          */
  98         if (mp->mnt_flag & MNT_UPDATE)
  99                 return (EOPNOTSUPP);
 100
 101         error = fdesc_allocvp(Froot, FD_ROOT, mp, &rvp);
 102         if (error)
 103                 return (error);
 104
 105         MALLOC(fmp, struct fdescmount *, sizeof(struct fdescmount),
 106                                 M_UFSMNT, M_WAITOK);    /* XXX */
 107         rvp->v_type = VDIR;
 108         rvp->v_flag |= VROOT;
 109         fmp->f_root = rvp;
 110         /* XXX -- don't mark as local to work around fts() problems */
 111         /*mp->mnt_flag |= MNT_LOCAL;*/
 112         mp->mnt_data = (qaddr_t) fmp;
 113         vfs_getnewfsid(mp);
 114
 115         (void) copyinstr(path, mp->mnt_stat.f_mntonname, MNAMELEN - 1, &size);
 116         bzero(mp->mnt_stat.f_mntonname + size, MNAMELEN - size);
 117         bzero(mp->mnt_stat.f_mntfromname, MNAMELEN);
 118         bcopy("fdesc", mp->mnt_stat.f_mntfromname, sizeof("fdesc"));
 119         return (0);
 120 }
 121
 122 int
 123 fdesc_start(mp, flags, p)
 124         struct mount *mp;
 125         int flags;
 126         struct proc *p;
 127 {
 128         return (0);
 129 }
 130
 131 int
 132 fdesc_unmount(mp, mntflags, p)
 133         struct mount *mp;
 134         int mntflags;
 135         struct proc *p;
 136 {
 137         int error;
 138         int flags = 0;
 139         int force = 0;
 140         struct vnode *rootvp = VFSTOFDESC(mp)->f_root;
 141
 142         if (mntflags & MNT_FORCE) {
 143                 flags |= FORCECLOSE;
 144                 force = 1;
 145         }
 146
 147         if ( (rootvp->v_usecount > 1) && !force )
 148                 return (EBUSY);
 149         if ( (error = vflush(mp, rootvp, flags)) && !force )
 150                 return (error);
 151
 152         /*
 153          * Release reference on underlying root vnode
 154          */
 155         vrele(rootvp);
 156         /*
 157          * And blow it away for future re-use
 158          */
 159         vgone(rootvp);
 160         /*
 161          * Finally, throw away the fdescmount structure
 162          */
 163         _FREE(mp->mnt_data, M_UFSMNT);  /* XXX */
 164         mp->mnt_data = 0;
 165
 166         return (0);
 167 }
 168
 169 int
 170 fdesc_root(mp, vpp)
 171         struct mount *mp;
 172         struct vnode **vpp;
 173 {
 174         struct proc *p = current_proc();        /* XXX */
 175         struct vnode *vp;
 176
 177         /*
 178          * Return locked reference to root.
 179          */
 180         vp = VFSTOFDESC(mp)->f_root;
 181         VREF(vp);
 182         vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, p);
 183         *vpp = vp;
 184         return (0);
 185 }
 186
 187 int
 188 fdesc_statfs(mp, sbp, p)
 189         struct mount *mp;
 190         struct statfs *sbp;
 191         struct proc *p;
 192 {
 193         struct filedesc *fdp;
 194         int lim;
 195         int i;
 196         int last;
 197         int freefd;
 198
 199         /*
 200          * Compute number of free file descriptors.
 201          * [ Strange results will ensue if the open file
 202          * limit is ever reduced below the current number
 203          * of open files... ]
 204          */
 205         lim = p->p_rlimit[RLIMIT_NOFILE].rlim_cur;
 206         fdp = p->p_fd;
 207         last = min(fdp->fd_nfiles, lim);
 208         freefd = 0;
 209         for (i = fdp->fd_freefile; i < last; i++)
 210                 if (fdp->fd_ofiles[i] == NULL &&
 211                                 !(fdp->fd_ofileflags[i] & UF_RESERVED))
 212                         freefd++;
 213
 214         /*
 215          * Adjust for the fact that the fdesc array may not
 216          * have been fully allocated yet.
 217          */
 218         if (fdp->fd_nfiles < lim)
 219                 freefd += (lim - fdp->fd_nfiles);
 220
 221         sbp->f_flags = 0;
 222         sbp->f_bsize = DEV_BSIZE;
 223         sbp->f_iosize = DEV_BSIZE;
 224         sbp->f_blocks = 2;              /* 1K to keep df happy */
 225         sbp->f_bfree = 0;
 226         sbp->f_bavail = 0;
 227         sbp->f_files = lim + 1;         /* Allow for "." */
 228         sbp->f_ffree = freefd;          /* See comments above */
 229         if (sbp != &mp->mnt_stat) {
 230                 sbp->f_type = mp->mnt_vfc->vfc_typenum;
 231                 bcopy(&mp->mnt_stat.f_fsid, &sbp->f_fsid, sizeof(sbp->f_fsid));
 232                 bcopy(mp->mnt_stat.f_mntonname, sbp->f_mntonname, MNAMELEN);
 233                 bcopy(mp->mnt_stat.f_mntfromname, sbp->f_mntfromname, MNAMELEN);
 234         }
 235         return (0);
 236 }
 237
 238 int
 239 fdesc_sync(mp, waitfor)
 240         struct mount *mp;
 241         int waitfor;
 242 {
 243
 244         return (0);
 245 }
 246
 247 #define fdesc_fhtovp ((int (*) __P((struct mount *, struct fid *, \
 248             struct mbuf *, struct vnode **, int *, struct ucred **)))eopnotsupp)
 249 #define fdesc_quotactl ((int (*) __P((struct mount *, int, uid_t, caddr_t, \
 250             struct proc *)))eopnotsupp)
 251 #define fdesc_sysctl ((int (*) __P((int *, u_int, void *, size_t *, void *, \
 252             size_t, struct proc *)))eopnotsupp)
 253 #define fdesc_vget ((int (*) __P((struct mount *, void *, struct vnode **))) \
 254             eopnotsupp)
 255 #define fdesc_vptofh ((int (*) __P((struct vnode *, struct fid *)))eopnotsupp)
 256
 257 struct vfsops fdesc_vfsops = {
 258         fdesc_mount,
 259         fdesc_start,
 260         fdesc_unmount,
 261         fdesc_root,
 262         fdesc_quotactl,
 263         fdesc_statfs,
 264         fdesc_sync,
 265         fdesc_vget,
 266         fdesc_fhtovp,
 267         fdesc_vptofh,
 268         fdesc_init,
 269         fdesc_sysctl,
 270 };