1 /* $NetBSD: fifo_vnops.c,v 1.22 1996/10/13 02:21:29 christos Exp $ */ 2 3 /* 4 * Copyright (c) 1990, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. All advertising materials mentioning features or use of this software 16 * must display the following acknowledgement: 17 * This product includes software developed by the University of 18 * California, Berkeley and its contributors. 19 * 4. Neither the name of the University nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 * 35 * @(#)fifo_vnops.c 8.4 (Berkeley) 8/10/94 36 */ 37 38 #include <sys/param.h> 39 #include <sys/proc.h> 40 #include <sys/time.h> 41 #include <sys/namei.h> 42 #include <sys/vnode.h> 43 #include <sys/socket.h> 44 #include <sys/socketvar.h> 45 #include <sys/stat.h> 46 #include <sys/systm.h> 47 #include <sys/ioctl.h> 48 #include <sys/file.h> 49 #include <sys/errno.h> 50 #include <sys/malloc.h> 51 #include <sys/un.h> 52 #include <sys/poll.h> 53 54 #include <miscfs/fifofs/fifo.h> 55 #include <miscfs/genfs/genfs.h> 56 57 /* 58 * This structure is associated with the FIFO vnode and stores 59 * the state associated with the FIFO. 60 */ 61 struct fifoinfo { 62 struct socket *fi_readsock; 63 struct socket *fi_writesock; 64 long fi_readers; 65 long fi_writers; 66 }; 67 68 int (**fifo_vnodeop_p) __P((void *)); 69 struct vnodeopv_entry_desc fifo_vnodeop_entries[] = { 70 { &vop_default_desc, vn_default_error }, 71 { &vop_lookup_desc, fifo_lookup }, /* lookup */ 72 { &vop_create_desc, fifo_create }, /* create */ 73 { &vop_mknod_desc, fifo_mknod }, /* mknod */ 74 { &vop_open_desc, fifo_open }, /* open */ 75 { &vop_close_desc, fifo_close }, /* close */ 76 { &vop_access_desc, fifo_access }, /* access */ 77 { &vop_getattr_desc, fifo_getattr }, /* getattr */ 78 { &vop_setattr_desc, fifo_setattr }, /* setattr */ 79 { &vop_read_desc, fifo_read }, /* read */ 80 { &vop_write_desc, fifo_write }, /* write */ 81 { &vop_lease_desc, fifo_lease_check }, /* lease */ 82 { &vop_ioctl_desc, fifo_ioctl }, /* ioctl */ 83 { &vop_poll_desc, fifo_poll }, /* poll */ 84 { &vop_mmap_desc, fifo_mmap }, /* mmap */ 85 { &vop_fsync_desc, fifo_fsync }, /* fsync */ 86 { &vop_seek_desc, fifo_seek }, /* seek */ 87 { &vop_remove_desc, fifo_remove }, /* remove */ 88 { &vop_link_desc, fifo_link }, /* link */ 89 { &vop_rename_desc, fifo_rename }, /* rename */ 90 { &vop_mkdir_desc, fifo_mkdir }, /* mkdir */ 91 { &vop_rmdir_desc, fifo_rmdir }, /* rmdir */ 92 { &vop_symlink_desc, fifo_symlink }, /* symlink */ 93 { &vop_readdir_desc, fifo_readdir }, /* readdir */ 94 { &vop_readlink_desc, fifo_readlink }, /* readlink */ 95 { &vop_abortop_desc, fifo_abortop }, /* abortop */ 96 { &vop_inactive_desc, fifo_inactive }, /* inactive */ 97 { &vop_reclaim_desc, fifo_reclaim }, /* reclaim */ 98 { &vop_lock_desc, fifo_lock }, /* lock */ 99 { &vop_unlock_desc, fifo_unlock }, /* unlock */ 100 { &vop_bmap_desc, fifo_bmap }, /* bmap */ 101 { &vop_strategy_desc, fifo_strategy }, /* strategy */ 102 { &vop_print_desc, fifo_print }, /* print */ 103 { &vop_islocked_desc, fifo_islocked }, /* islocked */ 104 { &vop_pathconf_desc, fifo_pathconf }, /* pathconf */ 105 { &vop_advlock_desc, fifo_advlock }, /* advlock */ 106 { &vop_blkatoff_desc, fifo_blkatoff }, /* blkatoff */ 107 { &vop_valloc_desc, fifo_valloc }, /* valloc */ 108 { &vop_vfree_desc, fifo_vfree }, /* vfree */ 109 { &vop_truncate_desc, fifo_truncate }, /* truncate */ 110 { &vop_update_desc, fifo_update }, /* update */ 111 { &vop_bwrite_desc, fifo_bwrite }, /* bwrite */ 112 { (struct vnodeop_desc*)NULL, (int(*) __P((void *)))NULL } 113 }; 114 struct vnodeopv_desc fifo_vnodeop_opv_desc = 115 { &fifo_vnodeop_p, fifo_vnodeop_entries }; 116 117 /* 118 * Trivial lookup routine that always fails. 119 */ 120 /* ARGSUSED */ 121 int 122 fifo_lookup(v) 123 void *v; 124 { 125 struct vop_lookup_args /* { 126 struct vnode * a_dvp; 127 struct vnode ** a_vpp; 128 struct componentname * a_cnp; 129 } */ *ap = v; 130 131 *ap->a_vpp = NULL; 132 return (ENOTDIR); 133 } 134 135 /* 136 * Open called to set up a new instance of a fifo or 137 * to find an active instance of a fifo. 138 */ 139 /* ARGSUSED */ 140 int 141 fifo_open(v) 142 void *v; 143 { 144 struct vop_open_args /* { 145 struct vnode *a_vp; 146 int a_mode; 147 struct ucred *a_cred; 148 struct proc *a_p; 149 } */ *ap = v; 150 register struct vnode *vp = ap->a_vp; 151 register struct fifoinfo *fip; 152 struct socket *rso, *wso; 153 int error; 154 static char openstr[] = "fifo"; 155 156 if ((fip = vp->v_fifoinfo) == NULL) { 157 MALLOC(fip, struct fifoinfo *, sizeof(*fip), M_VNODE, M_WAITOK); 158 vp->v_fifoinfo = fip; 159 if ((error = socreate(AF_LOCAL, &rso, SOCK_STREAM, 0)) != 0) { 160 free(fip, M_VNODE); 161 vp->v_fifoinfo = NULL; 162 return (error); 163 } 164 fip->fi_readsock = rso; 165 if ((error = socreate(AF_LOCAL, &wso, SOCK_STREAM, 0)) != 0) { 166 (void)soclose(rso); 167 free(fip, M_VNODE); 168 vp->v_fifoinfo = NULL; 169 return (error); 170 } 171 fip->fi_writesock = wso; 172 if ((error = unp_connect2(wso, rso)) != 0) { 173 (void)soclose(wso); 174 (void)soclose(rso); 175 free(fip, M_VNODE); 176 vp->v_fifoinfo = NULL; 177 return (error); 178 } 179 fip->fi_readers = fip->fi_writers = 0; 180 wso->so_state |= SS_CANTRCVMORE; 181 rso->so_state |= SS_CANTSENDMORE; 182 } 183 if (ap->a_mode & FREAD) { 184 if (fip->fi_readers++ == 0) { 185 fip->fi_writesock->so_state &= ~SS_CANTSENDMORE; 186 if (fip->fi_writers > 0) 187 wakeup((caddr_t)&fip->fi_writers); 188 } 189 } 190 if (ap->a_mode & FWRITE) { 191 if (fip->fi_writers++ == 0) { 192 fip->fi_readsock->so_state &= ~SS_CANTRCVMORE; 193 if (fip->fi_readers > 0) 194 wakeup((caddr_t)&fip->fi_readers); 195 } 196 } 197 if (ap->a_mode & FREAD) { 198 if (ap->a_mode & O_NONBLOCK) { 199 } else { 200 while (fip->fi_writers == 0) { 201 VOP_UNLOCK(vp); 202 error = tsleep((caddr_t)&fip->fi_readers, 203 PCATCH | PSOCK, openstr, 0); 204 VOP_LOCK(vp); 205 if (error) 206 goto bad; 207 } 208 } 209 } 210 if (ap->a_mode & FWRITE) { 211 if (ap->a_mode & O_NONBLOCK) { 212 if (fip->fi_readers == 0) { 213 error = ENXIO; 214 goto bad; 215 } 216 } else { 217 while (fip->fi_readers == 0) { 218 VOP_UNLOCK(vp); 219 error = tsleep((caddr_t)&fip->fi_writers, 220 PCATCH | PSOCK, openstr, 0); 221 VOP_LOCK(vp); 222 if (error) 223 goto bad; 224 } 225 } 226 } 227 return (0); 228 bad: 229 VOP_CLOSE(vp, ap->a_mode, ap->a_cred, ap->a_p); 230 return (error); 231 } 232 233 /* 234 * Vnode op for read 235 */ 236 /* ARGSUSED */ 237 int 238 fifo_read(v) 239 void *v; 240 { 241 struct vop_read_args /* { 242 struct vnode *a_vp; 243 struct uio *a_uio; 244 int a_ioflag; 245 struct ucred *a_cred; 246 } */ *ap = v; 247 register struct uio *uio = ap->a_uio; 248 register struct socket *rso = ap->a_vp->v_fifoinfo->fi_readsock; 249 int error, startresid; 250 251 #ifdef DIAGNOSTIC 252 if (uio->uio_rw != UIO_READ) 253 panic("fifo_read mode"); 254 #endif 255 if (uio->uio_resid == 0) 256 return (0); 257 if (ap->a_ioflag & IO_NDELAY) 258 rso->so_state |= SS_NBIO; 259 startresid = uio->uio_resid; 260 VOP_UNLOCK(ap->a_vp); 261 error = soreceive(rso, (struct mbuf **)0, uio, (struct mbuf **)0, 262 (struct mbuf **)0, (int *)0); 263 VOP_LOCK(ap->a_vp); 264 /* 265 * Clear EOF indication after first such return. 266 */ 267 if (uio->uio_resid == startresid) 268 rso->so_state &= ~SS_CANTRCVMORE; 269 if (ap->a_ioflag & IO_NDELAY) 270 rso->so_state &= ~SS_NBIO; 271 return (error); 272 } 273 274 /* 275 * Vnode op for write 276 */ 277 /* ARGSUSED */ 278 int 279 fifo_write(v) 280 void *v; 281 { 282 struct vop_write_args /* { 283 struct vnode *a_vp; 284 struct uio *a_uio; 285 int a_ioflag; 286 struct ucred *a_cred; 287 } */ *ap = v; 288 struct socket *wso = ap->a_vp->v_fifoinfo->fi_writesock; 289 int error; 290 291 #ifdef DIAGNOSTIC 292 if (ap->a_uio->uio_rw != UIO_WRITE) 293 panic("fifo_write mode"); 294 #endif 295 if (ap->a_ioflag & IO_NDELAY) 296 wso->so_state |= SS_NBIO; 297 VOP_UNLOCK(ap->a_vp); 298 error = sosend(wso, (struct mbuf *)0, ap->a_uio, 0, (struct mbuf *)0, 0); 299 VOP_LOCK(ap->a_vp); 300 if (ap->a_ioflag & IO_NDELAY) 301 wso->so_state &= ~SS_NBIO; 302 return (error); 303 } 304 305 /* 306 * Device ioctl operation. 307 */ 308 /* ARGSUSED */ 309 int 310 fifo_ioctl(v) 311 void *v; 312 { 313 struct vop_ioctl_args /* { 314 struct vnode *a_vp; 315 u_long a_command; 316 caddr_t a_data; 317 int a_fflag; 318 struct ucred *a_cred; 319 struct proc *a_p; 320 } */ *ap = v; 321 struct file filetmp; 322 int error; 323 324 if (ap->a_command == FIONBIO) 325 return (0); 326 if (ap->a_fflag & FREAD) { 327 filetmp.f_data = (caddr_t)ap->a_vp->v_fifoinfo->fi_readsock; 328 error = soo_ioctl(&filetmp, ap->a_command, ap->a_data, ap->a_p); 329 if (error) 330 return (error); 331 } 332 if (ap->a_fflag & FWRITE) { 333 filetmp.f_data = (caddr_t)ap->a_vp->v_fifoinfo->fi_writesock; 334 error = soo_ioctl(&filetmp, ap->a_command, ap->a_data, ap->a_p); 335 if (error) 336 return (error); 337 } 338 return (0); 339 } 340 341 /* ARGSUSED */ 342 int 343 fifo_poll(v) 344 void *v; 345 { 346 struct vop_poll_args /* { 347 struct vnode *a_vp; 348 int a_events; 349 struct proc *a_p; 350 } */ *ap = v; 351 struct file filetmp; 352 int revents = 0; 353 354 if (ap->a_events & (POLLIN | POLLPRI | POLLRDNORM | POLLRDBAND)) { 355 filetmp.f_data = (caddr_t)ap->a_vp->v_fifoinfo->fi_readsock; 356 if (filetmp.f_data) 357 revents |= soo_poll(&filetmp, ap->a_events, ap->a_p); 358 } 359 if (ap->a_events & (POLLOUT | POLLWRNORM | POLLWRBAND)) { 360 filetmp.f_data = (caddr_t)ap->a_vp->v_fifoinfo->fi_writesock; 361 if (filetmp.f_data) 362 revents |= soo_poll(&filetmp, ap->a_events, ap->a_p); 363 } 364 365 return (revents); 366 } 367 368 /* 369 * This is a noop, simply returning what one has been given. 370 */ 371 int 372 fifo_bmap(v) 373 void *v; 374 { 375 struct vop_bmap_args /* { 376 struct vnode *a_vp; 377 daddr_t a_bn; 378 struct vnode **a_vpp; 379 daddr_t *a_bnp; 380 } */ *ap = v; 381 382 if (ap->a_vpp != NULL) 383 *ap->a_vpp = ap->a_vp; 384 if (ap->a_bnp != NULL) 385 *ap->a_bnp = ap->a_bn; 386 return (0); 387 } 388 389 /* 390 * At the moment we do not do any locking. 391 */ 392 /* ARGSUSED */ 393 int 394 fifo_lock(v) 395 void *v; 396 { 397 return (0); 398 } 399 400 /* ARGSUSED */ 401 int 402 fifo_unlock(v) 403 void *v; 404 { 405 406 return (0); 407 } 408 409 /* 410 * Device close routine 411 */ 412 /* ARGSUSED */ 413 int 414 fifo_close(v) 415 void *v; 416 { 417 struct vop_close_args /* { 418 struct vnode *a_vp; 419 int a_fflag; 420 struct ucred *a_cred; 421 struct proc *a_p; 422 } */ *ap = v; 423 register struct vnode *vp = ap->a_vp; 424 register struct fifoinfo *fip = vp->v_fifoinfo; 425 int error1, error2; 426 427 if (ap->a_fflag & FREAD) { 428 if (--fip->fi_readers == 0) 429 socantsendmore(fip->fi_writesock); 430 } 431 if (ap->a_fflag & FWRITE) { 432 if (--fip->fi_writers == 0) 433 socantrcvmore(fip->fi_readsock); 434 } 435 if (vp->v_usecount > 1) 436 return (0); 437 error1 = soclose(fip->fi_readsock); 438 error2 = soclose(fip->fi_writesock); 439 FREE(fip, M_VNODE); 440 vp->v_fifoinfo = NULL; 441 if (error1) 442 return (error1); 443 return (error2); 444 } 445 446 /* 447 * Print out the contents of a fifo vnode. 448 */ 449 int 450 fifo_print(v) 451 void *v; 452 { 453 struct vop_print_args /* { 454 struct vnode *a_vp; 455 } */ *ap = v; 456 457 printf("tag VT_NON"); 458 fifo_printinfo(ap->a_vp); 459 printf("\n"); 460 return 0; 461 } 462 463 /* 464 * Print out internal contents of a fifo vnode. 465 */ 466 void 467 fifo_printinfo(vp) 468 struct vnode *vp; 469 { 470 register struct fifoinfo *fip = vp->v_fifoinfo; 471 472 printf(", fifo with %ld readers and %ld writers", 473 fip->fi_readers, fip->fi_writers); 474 } 475 476 /* 477 * Return POSIX pathconf information applicable to fifo's. 478 */ 479 int 480 fifo_pathconf(v) 481 void *v; 482 { 483 struct vop_pathconf_args /* { 484 struct vnode *a_vp; 485 int a_name; 486 register_t *a_retval; 487 } */ *ap = v; 488 489 switch (ap->a_name) { 490 case _PC_LINK_MAX: 491 *ap->a_retval = LINK_MAX; 492 return (0); 493 case _PC_PIPE_BUF: 494 *ap->a_retval = PIPE_BUF; 495 return (0); 496 case _PC_CHOWN_RESTRICTED: 497 *ap->a_retval = 1; 498 return (0); 499 default: 500 return (EINVAL); 501 } 502 /* NOTREACHED */ 503 } 504