1 /* $NetBSD: ptyfs_vfsops.c,v 1.8 2005/05/29 21:00:29 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. 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 */ 35 36 /* 37 * Pseudo-tty Filesystem 38 */ 39 40 #include <sys/cdefs.h> 41 __KERNEL_RCSID(0, "$NetBSD: ptyfs_vfsops.c,v 1.8 2005/05/29 21:00:29 christos Exp $"); 42 43 #include <sys/param.h> 44 #include <sys/systm.h> 45 #include <sys/sysctl.h> 46 #include <sys/conf.h> 47 #include <sys/proc.h> 48 #include <sys/vnode.h> 49 #include <sys/mount.h> 50 #include <sys/namei.h> 51 #include <sys/stat.h> 52 #include <sys/dirent.h> 53 #include <sys/malloc.h> 54 #include <sys/syslog.h> 55 #include <sys/select.h> 56 #include <sys/tty.h> 57 #include <sys/pty.h> 58 59 #include <fs/ptyfs/ptyfs.h> 60 #include <miscfs/specfs/specdev.h> 61 62 MALLOC_DEFINE(M_PTYFSMNT, "ptyfs mount", "ptyfs mount structures"); 63 64 void ptyfs_init(void); 65 void ptyfs_reinit(void); 66 void ptyfs_done(void); 67 int ptyfs_mount(struct mount *, const char *, void *, struct nameidata *, 68 struct proc *); 69 int ptyfs_start(struct mount *, int, struct proc *); 70 int ptyfs_unmount(struct mount *, int, struct proc *); 71 int ptyfs_statvfs(struct mount *, struct statvfs *, struct proc *); 72 int ptyfs_quotactl(struct mount *, int, uid_t, void *, struct proc *); 73 int ptyfs_sync(struct mount *, int, struct ucred *, struct proc *); 74 int ptyfs_vget(struct mount *, ino_t, struct vnode **); 75 int ptyfs_fhtovp(struct mount *, struct fid *, struct vnode **); 76 int ptyfs_checkexp(struct mount *, struct mbuf *, int *, struct ucred **); 77 int ptyfs_vptofh(struct vnode *, struct fid *); 78 79 static int ptyfs__allocvp(struct ptm_pty *, struct proc *, struct vnode **, 80 dev_t, char); 81 static int ptyfs__makename(struct ptm_pty *, char *, size_t, dev_t, char); 82 static void ptyfs__getvattr(struct ptm_pty *, struct proc *, struct vattr *); 83 84 /* 85 * ptm glue: When we mount, we make ptm point to us. 86 */ 87 struct ptm_pty *ptyfs_save_ptm; 88 89 struct ptm_pty ptm_ptyfspty = { 90 ptyfs__allocvp, 91 ptyfs__makename, 92 ptyfs__getvattr, 93 NULL 94 }; 95 96 static int 97 ptyfs__makename(struct ptm_pty *pt, char *tbuf, size_t bufsiz, dev_t dev, 98 char ms) 99 { 100 struct mount *mp = pt->arg; 101 size_t len; 102 103 switch (ms) { 104 case 'p': 105 /* We don't provide access to the master, should we? */ 106 len = snprintf(tbuf, bufsiz, "/dev/null"); 107 break; 108 case 't': 109 len = snprintf(tbuf, bufsiz, "%s/%d", mp->mnt_stat.f_mntonname, 110 minor(dev)); 111 break; 112 default: 113 return EINVAL; 114 } 115 116 return len >= bufsiz ? ENOSPC : 0; 117 } 118 119 120 static int 121 /*ARGSUSED*/ 122 ptyfs__allocvp(struct ptm_pty *pt, struct proc *p, struct vnode **vpp, 123 dev_t dev, char ms) 124 { 125 struct mount *mp = pt->arg; 126 ptyfstype type; 127 128 switch (ms) { 129 case 'p': 130 type = PTYFSptc; 131 break; 132 case 't': 133 type = PTYFSpts; 134 break; 135 default: 136 return EINVAL; 137 } 138 139 return ptyfs_allocvp(mp, vpp, type, minor(dev), p); 140 } 141 142 143 static void 144 ptyfs__getvattr(struct ptm_pty *pt, struct proc *p, struct vattr *vattr) 145 { 146 struct mount *mp = pt->arg; 147 struct ptyfsmount *pmnt = VFSTOPTY(mp); 148 VATTR_NULL(vattr); 149 /* get real uid */ 150 vattr->va_uid = p->p_cred->p_ruid; 151 vattr->va_gid = pmnt->pmnt_gid; 152 vattr->va_mode = pmnt->pmnt_mode; 153 } 154 155 156 void 157 ptyfs_init(void) 158 { 159 #ifdef _LKM 160 malloc_type_attach(M_PTYFSMNT); 161 #endif 162 ptyfs_hashinit(); 163 } 164 165 void 166 ptyfs_reinit(void) 167 { 168 ptyfs_hashreinit(); 169 } 170 171 void 172 ptyfs_done(void) 173 { 174 #ifdef _LKM 175 malloc_type_detach(M_PTYFSMNT); 176 #endif 177 ptyfs_hashdone(); 178 } 179 180 /* 181 * Mount the Pseudo tty params filesystem 182 */ 183 int 184 ptyfs_mount(struct mount *mp, const char *path, void *data, 185 struct nameidata *ndp, struct proc *p) 186 { 187 int error = 0; 188 struct ptyfsmount *pmnt; 189 struct ptyfs_args args; 190 191 if (UIO_MX & (UIO_MX - 1)) { 192 log(LOG_ERR, "ptyfs: invalid directory entry size"); 193 return EINVAL; 194 } 195 196 if (mp->mnt_flag & MNT_GETARGS) { 197 pmnt = VFSTOPTY(mp); 198 if (pmnt == NULL) 199 return EIO; 200 args.version = PTYFS_ARGSVERSION; 201 args.mode = pmnt->pmnt_mode; 202 args.gid = pmnt->pmnt_gid; 203 return copyout(&args, data, sizeof(args)); 204 } 205 206 if (mp->mnt_flag & MNT_UPDATE) 207 return EOPNOTSUPP; 208 209 if (data != NULL) { 210 error = copyin(data, &args, sizeof args); 211 if (error != 0) 212 return error; 213 214 if (args.version != PTYFS_ARGSVERSION) 215 return EINVAL; 216 } else { 217 /* 218 * Arguments are mandatory. 219 */ 220 return EINVAL; 221 } 222 223 pmnt = malloc(sizeof(struct ptyfsmount), M_UFSMNT, M_WAITOK); 224 225 mp->mnt_data = pmnt; 226 pmnt->pmnt_gid = args.gid; 227 pmnt->pmnt_mode = args.mode; 228 mp->mnt_flag |= MNT_LOCAL; 229 vfs_getnewfsid(mp); 230 231 if ((error = set_statvfs_info(path, UIO_USERSPACE, "ptyfs", 232 UIO_SYSSPACE, mp, p)) != 0) { 233 return error; 234 } 235 236 /* Point pty access to us */ 237 if (ptyfs_save_ptm != NULL) 238 return EBUSY; 239 240 ptm_ptyfspty.arg = mp; 241 ptyfs_save_ptm = pty_sethandler(&ptm_ptyfspty); 242 return 0; 243 } 244 245 /*ARGSUSED*/ 246 int 247 ptyfs_start(struct mount *mp, int flags, struct proc *p) 248 { 249 return 0; 250 } 251 252 /*ARGSUSED*/ 253 int 254 ptyfs_unmount(struct mount *mp, int mntflags, struct proc *p) 255 { 256 int error; 257 int flags = 0; 258 259 if (mntflags & MNT_FORCE) 260 flags |= FORCECLOSE; 261 262 if ((error = vflush(mp, 0, flags)) != 0) 263 return (error); 264 265 /* Restore where pty access was pointing */ 266 ptm_ptyfspty.arg = NULL; 267 (void)pty_sethandler(ptyfs_save_ptm); 268 ptyfs_save_ptm = NULL; 269 270 /* 271 * Finally, throw away the ptyfsmount structure 272 */ 273 free(mp->mnt_data, M_UFSMNT); 274 mp->mnt_data = 0; 275 276 return 0; 277 } 278 279 int 280 ptyfs_root(struct mount *mp, struct vnode **vpp) 281 { 282 /* setup "." */ 283 return ptyfs_allocvp(mp, vpp, PTYFSroot, 0, NULL); 284 } 285 286 /*ARGSUSED*/ 287 int 288 ptyfs_quotactl(struct mount *mp, int cmd, uid_t uid, void *arg, struct proc *p) 289 { 290 return EOPNOTSUPP; 291 } 292 293 /*ARGSUSED*/ 294 int 295 ptyfs_statvfs(struct mount *mp, struct statvfs *sbp, struct proc *p) 296 { 297 sbp->f_bsize = DEV_BSIZE; 298 sbp->f_frsize = DEV_BSIZE; 299 sbp->f_iosize = DEV_BSIZE; 300 sbp->f_blocks = 2; /* 1K to keep df happy */ 301 sbp->f_bfree = 0; 302 sbp->f_bavail = 0; 303 sbp->f_bresvd = 0; 304 sbp->f_files = 1024; /* XXX lie */ 305 sbp->f_ffree = 128; /* XXX lie */ 306 sbp->f_favail = 128; /* XXX lie */ 307 sbp->f_fresvd = 0; 308 sbp->f_namemax = MAXNAMLEN; 309 copy_statvfs_info(sbp, mp); 310 return 0; 311 } 312 313 /*ARGSUSED*/ 314 int 315 ptyfs_sync(struct mount *mp, int waitfor, struct ucred *uc, struct proc *p) 316 { 317 return 0; 318 } 319 320 /* 321 * Kernfs flat namespace lookup. 322 * Currently unsupported. 323 */ 324 /*ARGSUSED*/ 325 int 326 ptyfs_vget(struct mount *mp, ino_t ino, struct vnode **vpp) 327 { 328 return EOPNOTSUPP; 329 } 330 331 /*ARGSUSED*/ 332 int 333 ptyfs_fhtovp(struct mount *mp, struct fid *fhp, struct vnode **vpp) 334 { 335 return EOPNOTSUPP; 336 } 337 338 /*ARGSUSED*/ 339 int 340 ptyfs_checkexp(struct mount *mp, struct mbuf *mb, int *wh, struct ucred **anon) 341 { 342 return EOPNOTSUPP; 343 } 344 345 SYSCTL_SETUP(sysctl_vfs_ptyfs_setup, "sysctl vfs.ptyfs subtree setup") 346 { 347 348 sysctl_createv(clog, 0, NULL, NULL, 349 CTLFLAG_PERMANENT, 350 CTLTYPE_NODE, "vfs", NULL, 351 NULL, 0, NULL, 0, 352 CTL_VFS, CTL_EOL); 353 sysctl_createv(clog, 0, NULL, NULL, 354 CTLFLAG_PERMANENT, 355 CTLTYPE_NODE, "ptyfs", 356 SYSCTL_DESCR("Pty file system"), 357 NULL, 0, NULL, 0, 358 CTL_VFS, 23, CTL_EOL); 359 /* 360 * XXX the "23" above could be dynamic, thereby eliminating 361 * one more instance of the "number to vfs" mapping problem, 362 * but "23" is the order as taken from sys/mount.h 363 */ 364 } 365 366 367 /*ARGSUSED*/ 368 int 369 ptyfs_vptofh(struct vnode *vp, struct fid *fhp) 370 { 371 return EOPNOTSUPP; 372 } 373 374 extern const struct vnodeopv_desc ptyfs_vnodeop_opv_desc; 375 376 const struct vnodeopv_desc * const ptyfs_vnodeopv_descs[] = { 377 &ptyfs_vnodeop_opv_desc, 378 NULL, 379 }; 380 381 struct vfsops ptyfs_vfsops = { 382 MOUNT_PTYFS, 383 ptyfs_mount, 384 ptyfs_start, 385 ptyfs_unmount, 386 ptyfs_root, 387 ptyfs_quotactl, 388 ptyfs_statvfs, 389 ptyfs_sync, 390 ptyfs_vget, 391 ptyfs_fhtovp, 392 ptyfs_vptofh, 393 ptyfs_init, 394 ptyfs_reinit, 395 ptyfs_done, 396 NULL, 397 NULL, /* vfs_mountroot */ 398 ptyfs_checkexp, 399 (int (*)(struct mount *, struct vnode *, struct timespec *))eopnotsupp, 400 (int (*)(struct mount *, int, struct vnode *, int, const char *, 401 struct proc *))eopnotsupp, 402 ptyfs_vnodeopv_descs, 403 }; 404 VFS_ATTACH(ptyfs_vfsops); 405