1 /* $NetBSD: fdesc_vfsops.c,v 1.36 2001/11/15 09:48:21 lukem 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 1.36 2001/11/15 09:48:21 lukem 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 size_t size; 95 struct fdescmount *fmp; 96 struct vnode *rvp; 97 98 /* 99 * Update is a no-op 100 */ 101 if (mp->mnt_flag & MNT_UPDATE) 102 return (EOPNOTSUPP); 103 104 error = fdesc_allocvp(Froot, FD_ROOT, mp, &rvp); 105 if (error) 106 return (error); 107 108 MALLOC(fmp, struct fdescmount *, sizeof(struct fdescmount), 109 M_UFSMNT, M_WAITOK); /* XXX */ 110 rvp->v_type = VDIR; 111 rvp->v_flag |= VROOT; 112 fmp->f_root = rvp; 113 mp->mnt_flag |= MNT_LOCAL; 114 mp->mnt_data = (qaddr_t)fmp; 115 vfs_getnewfsid(mp); 116 117 (void) copyinstr(path, mp->mnt_stat.f_mntonname, MNAMELEN - 1, &size); 118 memset(mp->mnt_stat.f_mntonname + size, 0, MNAMELEN - size); 119 memset(mp->mnt_stat.f_mntfromname, 0, MNAMELEN); 120 memcpy(mp->mnt_stat.f_mntfromname, "fdesc", sizeof("fdesc")); 121 VOP_UNLOCK(rvp, 0); 122 return (0); 123 } 124 125 int 126 fdesc_start(mp, flags, p) 127 struct mount *mp; 128 int flags; 129 struct proc *p; 130 { 131 return (0); 132 } 133 134 int 135 fdesc_unmount(mp, mntflags, p) 136 struct mount *mp; 137 int mntflags; 138 struct proc *p; 139 { 140 int error; 141 int flags = 0; 142 struct vnode *rootvp = VFSTOFDESC(mp)->f_root; 143 144 if (mntflags & MNT_FORCE) 145 flags |= FORCECLOSE; 146 147 /* 148 * Clear out buffer cache. I don't think we 149 * ever get anything cached at this level at the 150 * moment, but who knows... 151 */ 152 if (rootvp->v_usecount > 1) 153 return (EBUSY); 154 if ((error = vflush(mp, rootvp, flags)) != 0) 155 return (error); 156 157 /* 158 * Release reference on underlying root vnode 159 */ 160 vrele(rootvp); 161 /* 162 * And blow it away for future re-use 163 */ 164 vgone(rootvp); 165 /* 166 * Finally, throw away the fdescmount structure 167 */ 168 free(mp->mnt_data, M_UFSMNT); /* XXX */ 169 mp->mnt_data = 0; 170 171 return (0); 172 } 173 174 int 175 fdesc_root(mp, vpp) 176 struct mount *mp; 177 struct vnode **vpp; 178 { 179 struct vnode *vp; 180 181 /* 182 * Return locked reference to root. 183 */ 184 vp = VFSTOFDESC(mp)->f_root; 185 VREF(vp); 186 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 187 *vpp = vp; 188 return (0); 189 } 190 191 int 192 fdesc_quotactl(mp, cmd, uid, arg, p) 193 struct mount *mp; 194 int cmd; 195 uid_t uid; 196 caddr_t arg; 197 struct proc *p; 198 { 199 200 return (EOPNOTSUPP); 201 } 202 203 int 204 fdesc_statfs(mp, sbp, p) 205 struct mount *mp; 206 struct statfs *sbp; 207 struct proc *p; 208 { 209 struct filedesc *fdp; 210 int lim; 211 int i; 212 int last; 213 int freefd; 214 215 /* 216 * Compute number of free file descriptors. 217 * [ Strange results will ensue if the open file 218 * limit is ever reduced below the current number 219 * of open files... ] 220 */ 221 lim = p->p_rlimit[RLIMIT_NOFILE].rlim_cur; 222 fdp = p->p_fd; 223 last = min(fdp->fd_nfiles, lim); 224 freefd = 0; 225 for (i = fdp->fd_freefile; i < last; i++) 226 if (fdp->fd_ofiles[i] == NULL) 227 freefd++; 228 229 /* 230 * Adjust for the fact that the fdesc array may not 231 * have been fully allocated yet. 232 */ 233 if (fdp->fd_nfiles < lim) 234 freefd += (lim - fdp->fd_nfiles); 235 236 sbp->f_bsize = DEV_BSIZE; 237 sbp->f_iosize = DEV_BSIZE; 238 sbp->f_blocks = 2; /* 1K to keep df happy */ 239 sbp->f_bfree = 0; 240 sbp->f_bavail = 0; 241 sbp->f_files = lim + 1; /* Allow for "." */ 242 sbp->f_ffree = freefd; /* See comments above */ 243 #ifdef COMPAT_09 244 sbp->f_type = 6; 245 #else 246 sbp->f_type = 0; 247 #endif 248 if (sbp != &mp->mnt_stat) { 249 memcpy(&sbp->f_fsid, &mp->mnt_stat.f_fsid, sizeof(sbp->f_fsid)); 250 memcpy(sbp->f_mntonname, mp->mnt_stat.f_mntonname, MNAMELEN); 251 memcpy(sbp->f_mntfromname, mp->mnt_stat.f_mntfromname, MNAMELEN); 252 } 253 strncpy(sbp->f_fstypename, mp->mnt_op->vfs_name, MFSNAMELEN); 254 return (0); 255 } 256 257 /*ARGSUSED*/ 258 int 259 fdesc_sync(mp, waitfor, uc, p) 260 struct mount *mp; 261 int waitfor; 262 struct ucred *uc; 263 struct proc *p; 264 { 265 266 return (0); 267 } 268 269 /* 270 * Fdesc flat namespace lookup. 271 * Currently unsupported. 272 */ 273 int 274 fdesc_vget(mp, ino, vpp) 275 struct mount *mp; 276 ino_t ino; 277 struct vnode **vpp; 278 { 279 280 return (EOPNOTSUPP); 281 } 282 283 284 /*ARGSUSED*/ 285 int 286 fdesc_fhtovp(mp, fhp, vpp) 287 struct mount *mp; 288 struct fid *fhp; 289 struct vnode **vpp; 290 { 291 292 return (EOPNOTSUPP); 293 } 294 295 /*ARGSUSED*/ 296 int 297 fdesc_checkexp(mp, nam, exflagsp, credanonp) 298 struct mount *mp; 299 struct mbuf *nam; 300 int *exflagsp; 301 struct ucred **credanonp; 302 { 303 304 return (EOPNOTSUPP); 305 } 306 307 /*ARGSUSED*/ 308 int 309 fdesc_vptofh(vp, fhp) 310 struct vnode *vp; 311 struct fid *fhp; 312 { 313 return (EOPNOTSUPP); 314 } 315 316 int 317 fdesc_sysctl(name, namelen, oldp, oldlenp, newp, newlen, p) 318 int *name; 319 u_int namelen; 320 void *oldp; 321 size_t *oldlenp; 322 void *newp; 323 size_t newlen; 324 struct proc *p; 325 { 326 return (EOPNOTSUPP); 327 } 328 329 extern const struct vnodeopv_desc fdesc_vnodeop_opv_desc; 330 331 const struct vnodeopv_desc * const fdesc_vnodeopv_descs[] = { 332 &fdesc_vnodeop_opv_desc, 333 NULL, 334 }; 335 336 struct vfsops fdesc_vfsops = { 337 MOUNT_FDESC, 338 fdesc_mount, 339 fdesc_start, 340 fdesc_unmount, 341 fdesc_root, 342 fdesc_quotactl, 343 fdesc_statfs, 344 fdesc_sync, 345 fdesc_vget, 346 fdesc_fhtovp, 347 fdesc_vptofh, 348 fdesc_init, 349 NULL, 350 fdesc_done, 351 fdesc_sysctl, 352 NULL, /* vfs_mountroot */ 353 fdesc_checkexp, 354 fdesc_vnodeopv_descs, 355 }; 356