1 /* 2 * Copyright (c) 1992, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * This code is derived from software donated to Berkeley by 6 * Jan-Simon Pendry. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. All advertising materials mentioning features or use of this software 17 * must display the following acknowledgement: 18 * This product includes software developed by the University of 19 * California, Berkeley and its contributors. 20 * 4. Neither the name of the University nor the names of its contributors 21 * may be used to endorse or promote products derived from this software 22 * without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 * 36 * @(#)fdesc_vfsops.c 8.4 (Berkeley) 1/21/94 37 * 38 * $Id: fdesc_vfsops.c,v 1.9 1993/04/06 15:28:33 jsp Exp $ 39 */ 40 41 /* 42 * /dev/fd Filesystem 43 */ 44 45 #include <sys/param.h> 46 #include <sys/systm.h> 47 #include <sys/time.h> 48 #include <sys/types.h> 49 #include <sys/proc.h> 50 #include <sys/resourcevar.h> 51 #include <sys/filedesc.h> 52 #include <sys/vnode.h> 53 #include <sys/mount.h> 54 #include <sys/namei.h> 55 #include <sys/malloc.h> 56 #include <miscfs/fdesc/fdesc.h> 57 58 /* 59 * Mount the per-process file descriptors (/dev/fd) 60 */ 61 int 62 fdesc_mount(mp, path, data, ndp, p) 63 struct mount *mp; 64 char *path; 65 caddr_t data; 66 struct nameidata *ndp; 67 struct proc *p; 68 { 69 int error = 0; 70 u_int size; 71 struct fdescmount *fmp; 72 struct vnode *rvp; 73 74 /* 75 * Update is a no-op 76 */ 77 if (mp->mnt_flag & MNT_UPDATE) 78 return (EOPNOTSUPP); 79 80 error = fdesc_allocvp(Froot, FD_ROOT, mp, &rvp); 81 if (error) 82 return (error); 83 84 MALLOC(fmp, struct fdescmount *, sizeof(struct fdescmount), 85 M_UFSMNT, M_WAITOK); /* XXX */ 86 rvp->v_type = VDIR; 87 rvp->v_flag |= VROOT; 88 fmp->f_root = rvp; 89 /* XXX -- don't mark as local to work around fts() problems */ 90 /*mp->mnt_flag |= MNT_LOCAL;*/ 91 mp->mnt_data = (qaddr_t) fmp; 92 getnewfsid(mp, MOUNT_FDESC); 93 94 (void) copyinstr(path, mp->mnt_stat.f_mntonname, MNAMELEN - 1, &size); 95 bzero(mp->mnt_stat.f_mntonname + size, MNAMELEN - size); 96 bzero(mp->mnt_stat.f_mntfromname, MNAMELEN); 97 bcopy("fdesc", mp->mnt_stat.f_mntfromname, sizeof("fdesc")); 98 return (0); 99 } 100 101 int 102 fdesc_start(mp, flags, p) 103 struct mount *mp; 104 int flags; 105 struct proc *p; 106 { 107 return (0); 108 } 109 110 int 111 fdesc_unmount(mp, mntflags, p) 112 struct mount *mp; 113 int mntflags; 114 struct proc *p; 115 { 116 int error; 117 int flags = 0; 118 extern int doforce; 119 struct vnode *rootvp = VFSTOFDESC(mp)->f_root; 120 121 if (mntflags & MNT_FORCE) { 122 /* fdesc can never be rootfs so don't check for it */ 123 if (!doforce) 124 return (EINVAL); 125 flags |= FORCECLOSE; 126 } 127 128 /* 129 * Clear out buffer cache. I don't think we 130 * ever get anything cached at this level at the 131 * moment, but who knows... 132 */ 133 if (rootvp->v_usecount > 1) 134 return (EBUSY); 135 if (error = vflush(mp, rootvp, flags)) 136 return (error); 137 138 /* 139 * Release reference on underlying root vnode 140 */ 141 vrele(rootvp); 142 /* 143 * And blow it away for future re-use 144 */ 145 vgone(rootvp); 146 /* 147 * Finally, throw away the fdescmount structure 148 */ 149 free(mp->mnt_data, M_UFSMNT); /* XXX */ 150 mp->mnt_data = 0; 151 152 return (0); 153 } 154 155 int 156 fdesc_root(mp, vpp) 157 struct mount *mp; 158 struct vnode **vpp; 159 { 160 struct vnode *vp; 161 162 /* 163 * Return locked reference to root. 164 */ 165 vp = VFSTOFDESC(mp)->f_root; 166 VREF(vp); 167 VOP_LOCK(vp); 168 *vpp = vp; 169 return (0); 170 } 171 172 int 173 fdesc_quotactl(mp, cmd, uid, arg, p) 174 struct mount *mp; 175 int cmd; 176 uid_t uid; 177 caddr_t arg; 178 struct proc *p; 179 { 180 181 return (EOPNOTSUPP); 182 } 183 184 int 185 fdesc_statfs(mp, sbp, p) 186 struct mount *mp; 187 struct statfs *sbp; 188 struct proc *p; 189 { 190 struct filedesc *fdp; 191 int lim; 192 int i; 193 int last; 194 int freefd; 195 196 /* 197 * Compute number of free file descriptors. 198 * [ Strange results will ensue if the open file 199 * limit is ever reduced below the current number 200 * of open files... ] 201 */ 202 lim = p->p_rlimit[RLIMIT_NOFILE].rlim_cur; 203 fdp = p->p_fd; 204 last = min(fdp->fd_nfiles, lim); 205 freefd = 0; 206 for (i = fdp->fd_freefile; i < last; i++) 207 if (fdp->fd_ofiles[i] == NULL) 208 freefd++; 209 210 /* 211 * Adjust for the fact that the fdesc array may not 212 * have been fully allocated yet. 213 */ 214 if (fdp->fd_nfiles < lim) 215 freefd += (lim - fdp->fd_nfiles); 216 217 sbp->f_type = MOUNT_FDESC; 218 sbp->f_flags = 0; 219 sbp->f_bsize = DEV_BSIZE; 220 sbp->f_iosize = DEV_BSIZE; 221 sbp->f_blocks = 2; /* 1K to keep df happy */ 222 sbp->f_bfree = 0; 223 sbp->f_bavail = 0; 224 sbp->f_files = lim + 1; /* Allow for "." */ 225 sbp->f_ffree = freefd; /* See comments above */ 226 if (sbp != &mp->mnt_stat) { 227 bcopy(&mp->mnt_stat.f_fsid, &sbp->f_fsid, sizeof(sbp->f_fsid)); 228 bcopy(mp->mnt_stat.f_mntonname, sbp->f_mntonname, MNAMELEN); 229 bcopy(mp->mnt_stat.f_mntfromname, sbp->f_mntfromname, MNAMELEN); 230 } 231 return (0); 232 } 233 234 int 235 fdesc_sync(mp, waitfor) 236 struct mount *mp; 237 int waitfor; 238 { 239 240 return (0); 241 } 242 243 /* 244 * Fdesc flat namespace lookup. 245 * Currently unsupported. 246 */ 247 int 248 fdesc_vget(mp, ino, vpp) 249 struct mount *mp; 250 ino_t ino; 251 struct vnode **vpp; 252 { 253 254 return (EOPNOTSUPP); 255 } 256 257 int 258 fdesc_fhtovp(mp, fhp, setgen, vpp) 259 struct mount *mp; 260 struct fid *fhp; 261 int setgen; 262 struct vnode **vpp; 263 { 264 return (EOPNOTSUPP); 265 } 266 267 int 268 fdesc_vptofh(vp, fhp) 269 struct vnode *vp; 270 struct fid *fhp; 271 { 272 273 return (EOPNOTSUPP); 274 } 275 276 struct vfsops fdesc_vfsops = { 277 fdesc_mount, 278 fdesc_start, 279 fdesc_unmount, 280 fdesc_root, 281 fdesc_quotactl, 282 fdesc_statfs, 283 fdesc_sync, 284 fdesc_vget, 285 fdesc_fhtovp, 286 fdesc_vptofh, 287 fdesc_init, 288 }; 289