1 /* $NetBSD: fdesc_vfsops.c,v 1.39 2003/04/16 21:44:22 christos Exp $ */ 2 3 /* 4 * Copyright (c) 1992, 1993, 1995 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 8.10 (Berkeley) 5/14/95 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/cdefs.h> 48 __KERNEL_RCSID(0, "$NetBSD: fdesc_vfsops.c,v 1.39 2003/04/16 21:44:22 christos Exp $"); 49 50 #if defined(_KERNEL_OPT) 51 #include "opt_compat_netbsd.h" 52 #endif 53 54 #include <sys/param.h> 55 #include <sys/systm.h> 56 #include <sys/time.h> 57 #include <sys/proc.h> 58 #include <sys/resourcevar.h> 59 #include <sys/filedesc.h> 60 #include <sys/vnode.h> 61 #include <sys/mount.h> 62 #include <sys/namei.h> 63 #include <sys/malloc.h> 64 #include <miscfs/fdesc/fdesc.h> 65 66 int fdesc_mount __P((struct mount *, const char *, void *, 67 struct nameidata *, struct proc *)); 68 int fdesc_start __P((struct mount *, int, struct proc *)); 69 int fdesc_unmount __P((struct mount *, int, struct proc *)); 70 int fdesc_quotactl __P((struct mount *, int, uid_t, caddr_t, 71 struct proc *)); 72 int fdesc_statfs __P((struct mount *, struct statfs *, struct proc *)); 73 int fdesc_sync __P((struct mount *, int, struct ucred *, struct proc *)); 74 int fdesc_vget __P((struct mount *, ino_t, struct vnode **)); 75 int fdesc_fhtovp __P((struct mount *, struct fid *, struct vnode **)); 76 int fdesc_checkexp __P((struct mount *, struct mbuf *, int *, 77 struct ucred **)); 78 int fdesc_vptofh __P((struct vnode *, struct fid *)); 79 int fdesc_sysctl __P((int *, u_int, void *, size_t *, void *, size_t, 80 struct proc *)); 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 const char *path; 89 void *data; 90 struct nameidata *ndp; 91 struct proc *p; 92 { 93 int error = 0; 94 struct fdescmount *fmp; 95 struct vnode *rvp; 96 97 if (mp->mnt_flag & MNT_GETARGS) 98 return 0; 99 /* 100 * Update is a no-op 101 */ 102 if (mp->mnt_flag & MNT_UPDATE) 103 return (EOPNOTSUPP); 104 105 error = fdesc_allocvp(Froot, FD_ROOT, mp, &rvp); 106 if (error) 107 return (error); 108 109 MALLOC(fmp, struct fdescmount *, sizeof(struct fdescmount), 110 M_UFSMNT, M_WAITOK); /* XXX */ 111 rvp->v_type = VDIR; 112 rvp->v_flag |= VROOT; 113 fmp->f_root = rvp; 114 mp->mnt_flag |= MNT_LOCAL; 115 mp->mnt_data = fmp; 116 vfs_getnewfsid(mp); 117 118 error = set_statfs_info(path, UIO_USERSPACE, "fdesc", UIO_SYSSPACE, 119 mp, p); 120 VOP_UNLOCK(rvp, 0); 121 return error; 122 } 123 124 int 125 fdesc_start(mp, flags, p) 126 struct mount *mp; 127 int flags; 128 struct proc *p; 129 { 130 return (0); 131 } 132 133 int 134 fdesc_unmount(mp, mntflags, p) 135 struct mount *mp; 136 int mntflags; 137 struct proc *p; 138 { 139 int error; 140 int flags = 0; 141 struct vnode *rootvp = VFSTOFDESC(mp)->f_root; 142 143 if (mntflags & MNT_FORCE) 144 flags |= FORCECLOSE; 145 146 /* 147 * Clear out buffer cache. I don't think we 148 * ever get anything cached at this level at the 149 * moment, but who knows... 150 */ 151 if (rootvp->v_usecount > 1) 152 return (EBUSY); 153 if ((error = vflush(mp, rootvp, flags)) != 0) 154 return (error); 155 156 /* 157 * Release reference on underlying root vnode 158 */ 159 vrele(rootvp); 160 /* 161 * And blow it away for future re-use 162 */ 163 vgone(rootvp); 164 /* 165 * Finally, throw away the fdescmount structure 166 */ 167 free(mp->mnt_data, M_UFSMNT); /* XXX */ 168 mp->mnt_data = 0; 169 170 return (0); 171 } 172 173 int 174 fdesc_root(mp, vpp) 175 struct mount *mp; 176 struct vnode **vpp; 177 { 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); 186 *vpp = vp; 187 return (0); 188 } 189 190 int 191 fdesc_quotactl(mp, cmd, uid, arg, p) 192 struct mount *mp; 193 int cmd; 194 uid_t uid; 195 caddr_t arg; 196 struct proc *p; 197 { 198 199 return (EOPNOTSUPP); 200 } 201 202 int 203 fdesc_statfs(mp, sbp, p) 204 struct mount *mp; 205 struct statfs *sbp; 206 struct proc *p; 207 { 208 struct filedesc *fdp; 209 int lim; 210 int i; 211 int last; 212 int freefd; 213 214 /* 215 * Compute number of free file descriptors. 216 * [ Strange results will ensue if the open file 217 * limit is ever reduced below the current number 218 * of open files... ] 219 */ 220 lim = p->p_rlimit[RLIMIT_NOFILE].rlim_cur; 221 fdp = p->p_fd; 222 last = min(fdp->fd_nfiles, lim); 223 freefd = 0; 224 for (i = fdp->fd_freefile; i < last; i++) 225 if (fdp->fd_ofiles[i] == NULL) 226 freefd++; 227 228 /* 229 * Adjust for the fact that the fdesc array may not 230 * have been fully allocated yet. 231 */ 232 if (fdp->fd_nfiles < lim) 233 freefd += (lim - fdp->fd_nfiles); 234 235 sbp->f_bsize = DEV_BSIZE; 236 sbp->f_iosize = DEV_BSIZE; 237 sbp->f_blocks = 2; /* 1K to keep df happy */ 238 sbp->f_bfree = 0; 239 sbp->f_bavail = 0; 240 sbp->f_files = lim + 1; /* Allow for "." */ 241 sbp->f_ffree = freefd; /* See comments above */ 242 #ifdef COMPAT_09 243 sbp->f_type = 6; 244 #else 245 sbp->f_type = 0; 246 #endif 247 copy_statfs_info(sbp, mp); 248 return (0); 249 } 250 251 /*ARGSUSED*/ 252 int 253 fdesc_sync(mp, waitfor, uc, p) 254 struct mount *mp; 255 int waitfor; 256 struct ucred *uc; 257 struct proc *p; 258 { 259 260 return (0); 261 } 262 263 /* 264 * Fdesc flat namespace lookup. 265 * Currently unsupported. 266 */ 267 int 268 fdesc_vget(mp, ino, vpp) 269 struct mount *mp; 270 ino_t ino; 271 struct vnode **vpp; 272 { 273 274 return (EOPNOTSUPP); 275 } 276 277 278 /*ARGSUSED*/ 279 int 280 fdesc_fhtovp(mp, fhp, vpp) 281 struct mount *mp; 282 struct fid *fhp; 283 struct vnode **vpp; 284 { 285 286 return (EOPNOTSUPP); 287 } 288 289 /*ARGSUSED*/ 290 int 291 fdesc_checkexp(mp, nam, exflagsp, credanonp) 292 struct mount *mp; 293 struct mbuf *nam; 294 int *exflagsp; 295 struct ucred **credanonp; 296 { 297 298 return (EOPNOTSUPP); 299 } 300 301 /*ARGSUSED*/ 302 int 303 fdesc_vptofh(vp, fhp) 304 struct vnode *vp; 305 struct fid *fhp; 306 { 307 return (EOPNOTSUPP); 308 } 309 310 int 311 fdesc_sysctl(name, namelen, oldp, oldlenp, newp, newlen, p) 312 int *name; 313 u_int namelen; 314 void *oldp; 315 size_t *oldlenp; 316 void *newp; 317 size_t newlen; 318 struct proc *p; 319 { 320 return (EOPNOTSUPP); 321 } 322 323 extern const struct vnodeopv_desc fdesc_vnodeop_opv_desc; 324 325 const struct vnodeopv_desc * const fdesc_vnodeopv_descs[] = { 326 &fdesc_vnodeop_opv_desc, 327 NULL, 328 }; 329 330 struct vfsops fdesc_vfsops = { 331 MOUNT_FDESC, 332 fdesc_mount, 333 fdesc_start, 334 fdesc_unmount, 335 fdesc_root, 336 fdesc_quotactl, 337 fdesc_statfs, 338 fdesc_sync, 339 fdesc_vget, 340 fdesc_fhtovp, 341 fdesc_vptofh, 342 fdesc_init, 343 NULL, 344 fdesc_done, 345 fdesc_sysctl, 346 NULL, /* vfs_mountroot */ 347 fdesc_checkexp, 348 fdesc_vnodeopv_descs, 349 }; 350