1 /* $NetBSD: fdesc_vfsops.c,v 1.15 1994/12/13 09:58:12 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 u_int 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 (void)fdesc_statfs(mp, &mp->mnt_stat, p); 100 return (0); 101 } 102 103 int 104 fdesc_start(mp, flags, p) 105 struct mount *mp; 106 int flags; 107 struct proc *p; 108 { 109 return (0); 110 } 111 112 int 113 fdesc_unmount(mp, mntflags, p) 114 struct mount *mp; 115 int mntflags; 116 struct proc *p; 117 { 118 int error; 119 int flags = 0; 120 extern int doforce; 121 struct vnode *rootvp = VFSTOFDESC(mp)->f_root; 122 123 if (mntflags & MNT_FORCE) { 124 /* fdesc can never be rootfs so don't check for it */ 125 if (!doforce) 126 return (EINVAL); 127 flags |= FORCECLOSE; 128 } 129 130 /* 131 * Clear out buffer cache. I don't think we 132 * ever get anything cached at this level at the 133 * moment, but who knows... 134 */ 135 if (rootvp->v_usecount > 1) 136 return (EBUSY); 137 if (error = vflush(mp, rootvp, flags)) 138 return (error); 139 140 /* 141 * Release reference on underlying root vnode 142 */ 143 vrele(rootvp); 144 /* 145 * And blow it away for future re-use 146 */ 147 vgone(rootvp); 148 /* 149 * Finally, throw away the fdescmount structure 150 */ 151 free(mp->mnt_data, M_UFSMNT); /* XXX */ 152 mp->mnt_data = 0; 153 154 return (0); 155 } 156 157 int 158 fdesc_root(mp, vpp) 159 struct mount *mp; 160 struct vnode **vpp; 161 { 162 struct vnode *vp; 163 164 /* 165 * Return locked reference to root. 166 */ 167 vp = VFSTOFDESC(mp)->f_root; 168 VREF(vp); 169 VOP_LOCK(vp); 170 *vpp = vp; 171 return (0); 172 } 173 174 int 175 fdesc_quotactl(mp, cmd, uid, arg, p) 176 struct mount *mp; 177 int cmd; 178 uid_t uid; 179 caddr_t arg; 180 struct proc *p; 181 { 182 183 return (EOPNOTSUPP); 184 } 185 186 int 187 fdesc_statfs(mp, sbp, p) 188 struct mount *mp; 189 struct statfs *sbp; 190 struct proc *p; 191 { 192 struct filedesc *fdp; 193 int lim; 194 int i; 195 int last; 196 int freefd; 197 198 /* 199 * Compute number of free file descriptors. 200 * [ Strange results will ensue if the open file 201 * limit is ever reduced below the current number 202 * of open files... ] 203 */ 204 lim = p->p_rlimit[RLIMIT_NOFILE].rlim_cur; 205 fdp = p->p_fd; 206 last = min(fdp->fd_nfiles, lim); 207 freefd = 0; 208 for (i = fdp->fd_freefile; i < last; i++) 209 if (fdp->fd_ofiles[i] == NULL) 210 freefd++; 211 212 /* 213 * Adjust for the fact that the fdesc array may not 214 * have been fully allocated yet. 215 */ 216 if (fdp->fd_nfiles < lim) 217 freefd += (lim - fdp->fd_nfiles); 218 219 #ifdef COMPAT_09 220 sbp->f_type = 6; 221 #else 222 sbp->f_type = 0; 223 #endif 224 sbp->f_bsize = DEV_BSIZE; 225 sbp->f_iosize = DEV_BSIZE; 226 sbp->f_blocks = 2; /* 1K to keep df happy */ 227 sbp->f_bfree = 0; 228 sbp->f_bavail = 0; 229 sbp->f_files = lim + 1; /* Allow for "." */ 230 sbp->f_ffree = freefd; /* See comments above */ 231 if (sbp != &mp->mnt_stat) { 232 bcopy(&mp->mnt_stat.f_fsid, &sbp->f_fsid, sizeof(sbp->f_fsid)); 233 bcopy(mp->mnt_stat.f_mntonname, sbp->f_mntonname, MNAMELEN); 234 bcopy(mp->mnt_stat.f_mntfromname, sbp->f_mntfromname, MNAMELEN); 235 } 236 strncpy(&sbp->f_fstypename[0], mp->mnt_op->vfs_name, MFSNAMELEN); 237 sbp->f_fstypename[MFSNAMELEN] = '\0'; 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 /* 251 * Fdesc flat namespace lookup. 252 * Currently unsupported. 253 */ 254 int 255 fdesc_vget(mp, ino, vpp) 256 struct mount *mp; 257 ino_t ino; 258 struct vnode **vpp; 259 { 260 261 return (EOPNOTSUPP); 262 } 263 264 int 265 fdesc_fhtovp(mp, fhp, setgen, vpp) 266 struct mount *mp; 267 struct fid *fhp; 268 int setgen; 269 struct vnode **vpp; 270 { 271 return (EOPNOTSUPP); 272 } 273 274 int 275 fdesc_vptofh(vp, fhp) 276 struct vnode *vp; 277 struct fid *fhp; 278 { 279 280 return (EOPNOTSUPP); 281 } 282 283 struct vfsops fdesc_vfsops = { 284 MOUNT_FDESC, 285 fdesc_mount, 286 fdesc_start, 287 fdesc_unmount, 288 fdesc_root, 289 fdesc_quotactl, 290 fdesc_statfs, 291 fdesc_sync, 292 fdesc_vget, 293 fdesc_fhtovp, 294 fdesc_vptofh, 295 fdesc_init, 296 }; 297