fdesc_vfsops.c revision 1.43.2.7
1 /* $NetBSD: fdesc_vfsops.c,v 1.43.2.7 2005/01/17 19:32:38 skrll 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. Neither the name of the University nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 * 34 * @(#)fdesc_vfsops.c 8.10 (Berkeley) 5/14/95 35 * 36 * #Id: fdesc_vfsops.c,v 1.9 1993/04/06 15:28:33 jsp Exp # 37 */ 38 39 /* 40 * /dev/fd Filesystem 41 */ 42 43 #include <sys/cdefs.h> 44 __KERNEL_RCSID(0, "$NetBSD: fdesc_vfsops.c,v 1.43.2.7 2005/01/17 19:32:38 skrll Exp $"); 45 46 #if defined(_KERNEL_OPT) 47 #include "opt_compat_netbsd.h" 48 #endif 49 50 #include <sys/param.h> 51 #include <sys/systm.h> 52 #include <sys/sysctl.h> 53 #include <sys/time.h> 54 #include <sys/proc.h> 55 #include <sys/resourcevar.h> 56 #include <sys/filedesc.h> 57 #include <sys/vnode.h> 58 #include <sys/mount.h> 59 #include <sys/dirent.h> 60 #include <sys/namei.h> 61 #include <sys/malloc.h> 62 #include <miscfs/fdesc/fdesc.h> 63 64 int fdesc_mount __P((struct mount *, const char *, void *, 65 struct nameidata *, struct lwp *)); 66 int fdesc_start __P((struct mount *, int, struct lwp *)); 67 int fdesc_unmount __P((struct mount *, int, struct lwp *)); 68 int fdesc_quotactl __P((struct mount *, int, uid_t, void *, 69 struct lwp *)); 70 int fdesc_statvfs __P((struct mount *, struct statvfs *, struct lwp *)); 71 int fdesc_sync __P((struct mount *, int, struct ucred *, struct lwp *)); 72 int fdesc_vget __P((struct mount *, ino_t, struct vnode **)); 73 int fdesc_fhtovp __P((struct mount *, struct fid *, struct vnode **)); 74 int fdesc_checkexp __P((struct mount *, struct mbuf *, int *, 75 struct ucred **)); 76 int fdesc_vptofh __P((struct vnode *, struct fid *)); 77 78 /* 79 * Mount the per-process file descriptors (/dev/fd) 80 */ 81 int 82 fdesc_mount(mp, path, data, ndp, l) 83 struct mount *mp; 84 const char *path; 85 void *data; 86 struct nameidata *ndp; 87 struct lwp *l; 88 { 89 int error = 0; 90 struct fdescmount *fmp; 91 struct vnode *rvp; 92 93 if (mp->mnt_flag & MNT_GETARGS) 94 return 0; 95 /* 96 * Update is a no-op 97 */ 98 if (mp->mnt_flag & MNT_UPDATE) 99 return (EOPNOTSUPP); 100 101 error = fdesc_allocvp(Froot, FD_ROOT, mp, &rvp); 102 if (error) 103 return (error); 104 105 MALLOC(fmp, struct fdescmount *, sizeof(struct fdescmount), 106 M_UFSMNT, M_WAITOK); /* XXX */ 107 rvp->v_type = VDIR; 108 rvp->v_flag |= VROOT; 109 fmp->f_root = rvp; 110 mp->mnt_stat.f_namemax = MAXNAMLEN; 111 mp->mnt_flag |= MNT_LOCAL; 112 mp->mnt_data = fmp; 113 vfs_getnewfsid(mp); 114 115 error = set_statvfs_info(path, UIO_USERSPACE, "fdesc", UIO_SYSSPACE, 116 mp, l); 117 VOP_UNLOCK(rvp, 0); 118 return error; 119 } 120 121 int 122 fdesc_start(mp, flags, l) 123 struct mount *mp; 124 int flags; 125 struct lwp *l; 126 { 127 return (0); 128 } 129 130 int 131 fdesc_unmount(mp, mntflags, l) 132 struct mount *mp; 133 int mntflags; 134 struct lwp *l; 135 { 136 int error; 137 int flags = 0; 138 struct vnode *rootvp = VFSTOFDESC(mp)->f_root; 139 140 if (mntflags & MNT_FORCE) 141 flags |= FORCECLOSE; 142 143 /* 144 * Clear out buffer cache. I don't think we 145 * ever get anything cached at this level at the 146 * moment, but who knows... 147 */ 148 if (rootvp->v_usecount > 1) 149 return (EBUSY); 150 if ((error = vflush(mp, rootvp, flags)) != 0) 151 return (error); 152 153 /* 154 * Release reference on underlying root vnode 155 */ 156 vrele(rootvp); 157 /* 158 * And blow it away for future re-use 159 */ 160 vgone(rootvp); 161 /* 162 * Finally, throw away the fdescmount structure 163 */ 164 free(mp->mnt_data, M_UFSMNT); /* XXX */ 165 mp->mnt_data = 0; 166 167 return (0); 168 } 169 170 int 171 fdesc_root(mp, vpp) 172 struct mount *mp; 173 struct vnode **vpp; 174 { 175 struct vnode *vp; 176 177 /* 178 * Return locked reference to root. 179 */ 180 vp = VFSTOFDESC(mp)->f_root; 181 VREF(vp); 182 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 183 *vpp = vp; 184 return (0); 185 } 186 187 int 188 fdesc_quotactl(mp, cmd, uid, arg, l) 189 struct mount *mp; 190 int cmd; 191 uid_t uid; 192 void *arg; 193 struct lwp *l; 194 { 195 196 return (EOPNOTSUPP); 197 } 198 199 int 200 fdesc_statvfs(mp, sbp, l) 201 struct mount *mp; 202 struct statvfs *sbp; 203 struct lwp *l; 204 { 205 struct filedesc *fdp; 206 struct proc *p; 207 int lim; 208 int i; 209 int last; 210 int freefd; 211 212 /* 213 * Compute number of free file descriptors. 214 * [ Strange results will ensue if the open file 215 * limit is ever reduced below the current number 216 * of open files... ] 217 */ 218 p = l->l_proc; 219 lim = p->p_rlimit[RLIMIT_NOFILE].rlim_cur; 220 fdp = p->p_fd; 221 last = min(fdp->fd_nfiles, lim); 222 freefd = 0; 223 for (i = fdp->fd_freefile; i < last; i++) 224 if (fdp->fd_ofiles[i] == NULL) 225 freefd++; 226 227 /* 228 * Adjust for the fact that the fdesc array may not 229 * have been fully allocated yet. 230 */ 231 if (fdp->fd_nfiles < lim) 232 freefd += (lim - fdp->fd_nfiles); 233 234 sbp->f_bsize = DEV_BSIZE; 235 sbp->f_frsize = 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_bresvd = 0; 241 sbp->f_files = lim + 1; /* Allow for "." */ 242 sbp->f_ffree = freefd; /* See comments above */ 243 sbp->f_favail = freefd; /* See comments above */ 244 sbp->f_fresvd = 0; 245 copy_statvfs_info(sbp, mp); 246 return (0); 247 } 248 249 /*ARGSUSED*/ 250 int 251 fdesc_sync(mp, waitfor, uc, l) 252 struct mount *mp; 253 int waitfor; 254 struct ucred *uc; 255 struct lwp *l; 256 { 257 258 return (0); 259 } 260 261 /* 262 * Fdesc flat namespace lookup. 263 * Currently unsupported. 264 */ 265 int 266 fdesc_vget(mp, ino, vpp) 267 struct mount *mp; 268 ino_t ino; 269 struct vnode **vpp; 270 { 271 272 return (EOPNOTSUPP); 273 } 274 275 276 /*ARGSUSED*/ 277 int 278 fdesc_fhtovp(mp, fhp, vpp) 279 struct mount *mp; 280 struct fid *fhp; 281 struct vnode **vpp; 282 { 283 284 return (EOPNOTSUPP); 285 } 286 287 /*ARGSUSED*/ 288 int 289 fdesc_checkexp(mp, nam, exflagsp, credanonp) 290 struct mount *mp; 291 struct mbuf *nam; 292 int *exflagsp; 293 struct ucred **credanonp; 294 { 295 296 return (EOPNOTSUPP); 297 } 298 299 /*ARGSUSED*/ 300 int 301 fdesc_vptofh(vp, fhp) 302 struct vnode *vp; 303 struct fid *fhp; 304 { 305 return (EOPNOTSUPP); 306 } 307 308 SYSCTL_SETUP(sysctl_vfs_fdesc_setup, "sysctl vfs.fdesc subtree setup") 309 { 310 311 sysctl_createv(clog, 0, NULL, NULL, 312 CTLFLAG_PERMANENT, 313 CTLTYPE_NODE, "vfs", NULL, 314 NULL, 0, NULL, 0, 315 CTL_VFS, CTL_EOL); 316 sysctl_createv(clog, 0, NULL, NULL, 317 CTLFLAG_PERMANENT, 318 CTLTYPE_NODE, "fdesc", 319 SYSCTL_DESCR("File-descriptor file system"), 320 NULL, 0, NULL, 0, 321 CTL_VFS, 7, CTL_EOL); 322 /* 323 * XXX the "7" above could be dynamic, thereby eliminating one 324 * more instance of the "number to vfs" mapping problem, but 325 * "7" is the order as taken from sys/mount.h 326 */ 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_statvfs, 344 fdesc_sync, 345 fdesc_vget, 346 fdesc_fhtovp, 347 fdesc_vptofh, 348 fdesc_init, 349 NULL, 350 fdesc_done, 351 NULL, 352 NULL, /* vfs_mountroot */ 353 fdesc_checkexp, 354 (int (*)(struct mount *, struct vnode *, struct timespec *)) eopnotsupp, 355 vfs_stdextattrctl, 356 fdesc_vnodeopv_descs, 357 }; 358
Indexes created Wed Oct 15 16:09:53 GMT 2025