1 /* $NetBSD: fdesc_vfsops.c,v 1.19 1995/03/09 12:05:50 mycroft Exp $ */ 2 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. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by the University of 21 * California, Berkeley and its contributors. 22 * 4. Neither the name of the University nor the names of its contributors 23 * may be used to endorse or promote products derived from this software 24 * without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 29 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 36 * SUCH DAMAGE. 37 * 38 * @(#)fdesc_vfsops.c 8.4 (Berkeley) 1/21/94 39 * 40 * #Id: fdesc_vfsops.c,v 1.9 1993/04/06 15:28:33 jsp Exp # 41 */ 42 43 /* 44 * /dev/fd Filesystem 45 */ 46 47 #include <sys/param.h> 48 #include <sys/systm.h> 49 #include <sys/time.h> 50 #include <sys/types.h> 51 #include <sys/proc.h> 52 #include <sys/resourcevar.h> 53 #include <sys/filedesc.h> 54 #include <sys/vnode.h> 55 #include <sys/mount.h> 56 #include <sys/namei.h> 57 #include <sys/malloc.h> 58 #include <miscfs/fdesc/fdesc.h> 59 60 /* 61 * Mount the per-process file descriptors (/dev/fd) 62 */ 63 int 64 fdesc_mount(mp, path, data, ndp, p) 65 struct mount *mp; 66 char *path; 67 caddr_t data; 68 struct nameidata *ndp; 69 struct proc *p; 70 { 71 int error = 0; 72 size_t size; 73 struct fdescmount *fmp; 74 struct vnode *rvp; 75 76 /* 77 * Update is a no-op 78 */ 79 if (mp->mnt_flag & MNT_UPDATE) 80 return (EOPNOTSUPP); 81 82 error = fdesc_allocvp(Froot, FD_ROOT, mp, &rvp); 83 if (error) 84 return (error); 85 86 MALLOC(fmp, struct fdescmount *, sizeof(struct fdescmount), 87 M_UFSMNT, M_WAITOK); /* XXX */ 88 rvp->v_type = VDIR; 89 rvp->v_flag |= VROOT; 90 fmp->f_root = rvp; 91 mp->mnt_flag |= MNT_LOCAL; 92 mp->mnt_data = (qaddr_t)fmp; 93 getnewfsid(mp, makefstype(MOUNT_FDESC)); 94 95 (void) copyinstr(path, mp->mnt_stat.f_mntonname, MNAMELEN - 1, &size); 96 bzero(mp->mnt_stat.f_mntonname + size, MNAMELEN - size); 97 bzero(mp->mnt_stat.f_mntfromname, MNAMELEN); 98 bcopy("fdesc", mp->mnt_stat.f_mntfromname, sizeof("fdesc")); 99 return (0); 100 } 101 102 int 103 fdesc_start(mp, flags, p) 104 struct mount *mp; 105 int flags; 106 struct proc *p; 107 { 108 return (0); 109 } 110 111 int 112 fdesc_unmount(mp, mntflags, p) 113 struct mount *mp; 114 int mntflags; 115 struct proc *p; 116 { 117 int error; 118 int flags = 0; 119 extern int doforce; 120 struct vnode *rootvp = VFSTOFDESC(mp)->f_root; 121 122 if (mntflags & MNT_FORCE) { 123 /* fdesc can never be rootfs so don't check for it */ 124 if (!doforce) 125 return (EINVAL); 126 flags |= FORCECLOSE; 127 } 128 129 /* 130 * Clear out buffer cache. I don't think we 131 * ever get anything cached at this level at the 132 * moment, but who knows... 133 */ 134 if (rootvp->v_usecount > 1) 135 return (EBUSY); 136 if (error = vflush(mp, rootvp, flags)) 137 return (error); 138 139 /* 140 * Release reference on underlying root vnode 141 */ 142 vrele(rootvp); 143 /* 144 * And blow it away for future re-use 145 */ 146 vgone(rootvp); 147 /* 148 * Finally, throw away the fdescmount structure 149 */ 150 free(mp->mnt_data, M_UFSMNT); /* XXX */ 151 mp->mnt_data = 0; 152 153 return (0); 154 } 155 156 int 157 fdesc_root(mp, vpp) 158 struct mount *mp; 159 struct vnode **vpp; 160 { 161 struct vnode *vp; 162 163 /* 164 * Return locked reference to root. 165 */ 166 vp = VFSTOFDESC(mp)->f_root; 167 VREF(vp); 168 VOP_LOCK(vp); 169 *vpp = vp; 170 return (0); 171 } 172 173 int 174 fdesc_quotactl(mp, cmd, uid, arg, p) 175 struct mount *mp; 176 int cmd; 177 uid_t uid; 178 caddr_t arg; 179 struct proc *p; 180 { 181 182 return (EOPNOTSUPP); 183 } 184 185 int 186 fdesc_statfs(mp, sbp, p) 187 struct mount *mp; 188 struct statfs *sbp; 189 struct proc *p; 190 { 191 struct filedesc *fdp; 192 int lim; 193 int i; 194 int last; 195 int freefd; 196 197 /* 198 * Compute number of free file descriptors. 199 * [ Strange results will ensue if the open file 200 * limit is ever reduced below the current number 201 * of open files... ] 202 */ 203 lim = p->p_rlimit[RLIMIT_NOFILE].rlim_cur; 204 fdp = p->p_fd; 205 last = min(fdp->fd_nfiles, lim); 206 freefd = 0; 207 for (i = fdp->fd_freefile; i < last; i++) 208 if (fdp->fd_ofiles[i] == NULL) 209 freefd++; 210 211 /* 212 * Adjust for the fact that the fdesc array may not 213 * have been fully allocated yet. 214 */ 215 if (fdp->fd_nfiles < lim) 216 freefd += (lim - fdp->fd_nfiles); 217 218 #ifdef COMPAT_09 219 sbp->f_type = 6; 220 #else 221 sbp->f_type = 0; 222 #endif 223 sbp->f_bsize = DEV_BSIZE; 224 sbp->f_iosize = DEV_BSIZE; 225 sbp->f_blocks = 2; /* 1K to keep df happy */ 226 sbp->f_bfree = 0; 227 sbp->f_bavail = 0; 228 sbp->f_files = lim + 1; /* Allow for "." */ 229 sbp->f_ffree = freefd; /* See comments above */ 230 if (sbp != &mp->mnt_stat) { 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 strncpy(sbp->f_fstypename, mp->mnt_op->vfs_name, MFSNAMELEN); 236 sbp->f_fstypename[MFSNAMELEN] = '\0'; 237 return (0); 238 } 239 240 int 241 fdesc_sync(mp, waitfor) 242 struct mount *mp; 243 int waitfor; 244 { 245 246 return (0); 247 } 248 249 /* 250 * Fdesc flat namespace lookup. 251 * Currently unsupported. 252 */ 253 int 254 fdesc_vget(mp, ino, vpp) 255 struct mount *mp; 256 ino_t ino; 257 struct vnode **vpp; 258 { 259 260 return (EOPNOTSUPP); 261 } 262 263 int 264 fdesc_fhtovp(mp, fhp, setgen, vpp) 265 struct mount *mp; 266 struct fid *fhp; 267 int setgen; 268 struct vnode **vpp; 269 { 270 return (EOPNOTSUPP); 271 } 272 273 int 274 fdesc_vptofh(vp, fhp) 275 struct vnode *vp; 276 struct fid *fhp; 277 { 278 279 return (EOPNOTSUPP); 280 } 281 282 struct vfsops fdesc_vfsops = { 283 MOUNT_FDESC, 284 fdesc_mount, 285 fdesc_start, 286 fdesc_unmount, 287 fdesc_root, 288 fdesc_quotactl, 289 fdesc_statfs, 290 fdesc_sync, 291 fdesc_vget, 292 fdesc_fhtovp, 293 fdesc_vptofh, 294 fdesc_init, 295 }; 296