1 /* 2 * Copyright (c) 1990, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 * 33 * @(#)fifo_vnops.c 8.2 (Berkeley) 1/4/94 34 * $Id: fifo_vnops.c,v 1.16 1996/02/13 18:16:23 wollman Exp $ 35 */ 36 37 #include <sys/param.h> 38 #include <sys/kernel.h> 39 #include <sys/proc.h> 40 #include <sys/time.h> 41 #include <sys/namei.h> 42 #include <sys/unistd.h> 43 #include <sys/vnode.h> 44 #include <sys/socket.h> 45 #include <sys/socketvar.h> 46 #include <sys/stat.h> 47 #include <sys/systm.h> 48 #include <sys/ioctl.h> 49 #include <sys/file.h> 50 #include <sys/errno.h> 51 #include <sys/malloc.h> 52 #include <sys/un.h> 53 #include <miscfs/fifofs/fifo.h> 54 55 /* 56 * This structure is associated with the FIFO vnode and stores 57 * the state associated with the FIFO. 58 */ 59 struct fifoinfo { 60 struct socket *fi_readsock; 61 struct socket *fi_writesock; 62 long fi_readers; 63 long fi_writers; 64 }; 65 66 static int fifo_ebadf __P((void)); 67 static int fifo_unlock __P((struct vop_unlock_args *)); 68 static int fifo_lock __P((struct vop_lock_args *)); 69 static int fifo_print __P((struct vop_print_args *)); 70 71 vop_t **fifo_vnodeop_p; 72 static struct vnodeopv_entry_desc fifo_vnodeop_entries[] = { 73 { &vop_default_desc, (vop_t *)vn_default_error }, 74 { &vop_lookup_desc, (vop_t *)fifo_lookup }, /* lookup */ 75 { &vop_create_desc, (vop_t *)fifo_create }, /* create */ 76 { &vop_mknod_desc, (vop_t *)fifo_mknod }, /* mknod */ 77 { &vop_open_desc, (vop_t *)fifo_open }, /* open */ 78 { &vop_close_desc, (vop_t *)fifo_close }, /* close */ 79 { &vop_access_desc, (vop_t *)fifo_access }, /* access */ 80 { &vop_getattr_desc, (vop_t *)fifo_getattr }, /* getattr */ 81 { &vop_setattr_desc, (vop_t *)fifo_setattr }, /* setattr */ 82 { &vop_read_desc, (vop_t *)fifo_read }, /* read */ 83 { &vop_write_desc, (vop_t *)fifo_write }, /* write */ 84 { &vop_ioctl_desc, (vop_t *)fifo_ioctl }, /* ioctl */ 85 { &vop_select_desc, (vop_t *)fifo_select }, /* select */ 86 { &vop_mmap_desc, (vop_t *)fifo_mmap }, /* mmap */ 87 { &vop_fsync_desc, (vop_t *)fifo_fsync }, /* fsync */ 88 { &vop_seek_desc, (vop_t *)fifo_seek }, /* seek */ 89 { &vop_remove_desc, (vop_t *)fifo_remove }, /* remove */ 90 { &vop_link_desc, (vop_t *)fifo_link }, /* link */ 91 { &vop_rename_desc, (vop_t *)fifo_rename }, /* rename */ 92 { &vop_mkdir_desc, (vop_t *)fifo_mkdir }, /* mkdir */ 93 { &vop_rmdir_desc, (vop_t *)fifo_rmdir }, /* rmdir */ 94 { &vop_symlink_desc, (vop_t *)fifo_symlink }, /* symlink */ 95 { &vop_readdir_desc, (vop_t *)fifo_readdir }, /* readdir */ 96 { &vop_readlink_desc, (vop_t *)fifo_readlink }, /* readlink */ 97 { &vop_abortop_desc, (vop_t *)fifo_abortop }, /* abortop */ 98 { &vop_inactive_desc, (vop_t *)fifo_inactive }, /* inactive */ 99 { &vop_reclaim_desc, (vop_t *)fifo_reclaim }, /* reclaim */ 100 { &vop_lock_desc, (vop_t *)fifo_lock }, /* lock */ 101 { &vop_unlock_desc, (vop_t *)fifo_unlock }, /* unlock */ 102 { &vop_bmap_desc, (vop_t *)fifo_bmap }, /* bmap */ 103 { &vop_strategy_desc, (vop_t *)fifo_strategy }, /* strategy */ 104 { &vop_print_desc, (vop_t *)fifo_print }, /* print */ 105 { &vop_islocked_desc, (vop_t *)fifo_islocked }, /* islocked */ 106 { &vop_pathconf_desc, (vop_t *)fifo_pathconf }, /* pathconf */ 107 { &vop_advlock_desc, (vop_t *)fifo_advlock }, /* advlock */ 108 { &vop_blkatoff_desc, (vop_t *)fifo_blkatoff }, /* blkatoff */ 109 { &vop_valloc_desc, (vop_t *)fifo_valloc }, /* valloc */ 110 { &vop_vfree_desc, (vop_t *)fifo_vfree }, /* vfree */ 111 { &vop_truncate_desc, (vop_t *)fifo_truncate }, /* truncate */ 112 { &vop_update_desc, (vop_t *)fifo_update }, /* update */ 113 { &vop_bwrite_desc, (vop_t *)fifo_bwrite }, /* bwrite */ 114 { NULL, NULL } 115 }; 116 static struct vnodeopv_desc fifo_vnodeop_opv_desc = 117 { &fifo_vnodeop_p, fifo_vnodeop_entries }; 118 119 VNODEOP_SET(fifo_vnodeop_opv_desc); 120 121 /* 122 * Trivial lookup routine that always fails. 123 */ 124 /* ARGSUSED */ 125 int 126 fifo_lookup(ap) 127 struct vop_lookup_args /* { 128 struct vnode * a_dvp; 129 struct vnode ** a_vpp; 130 struct componentname * a_cnp; 131 } */ *ap; 132 { 133 134 *ap->a_vpp = NULL; 135 return (ENOTDIR); 136 } 137 138 /* 139 * Open called to set up a new instance of a fifo or 140 * to find an active instance of a fifo. 141 */ 142 /* ARGSUSED */ 143 int 144 fifo_open(ap) 145 struct vop_open_args /* { 146 struct vnode *a_vp; 147 int a_mode; 148 struct ucred *a_cred; 149 struct proc *a_p; 150 } */ *ap; 151 { 152 register struct vnode *vp = ap->a_vp; 153 register struct fifoinfo *fip; 154 struct socket *rso, *wso; 155 int error; 156 static char openstr[] = "fifo"; 157 158 if ((fip = vp->v_fifoinfo) == NULL) { 159 MALLOC(fip, struct fifoinfo *, sizeof(*fip), M_VNODE, M_WAITOK); 160 vp->v_fifoinfo = fip; 161 error = socreate(AF_UNIX, &rso, SOCK_STREAM, 0, ap->a_p); 162 if (error) { 163 free(fip, M_VNODE); 164 vp->v_fifoinfo = NULL; 165 return (error); 166 } 167 fip->fi_readsock = rso; 168 error = socreate(AF_UNIX, &wso, SOCK_STREAM, 0, ap->a_p); 169 if (error) { 170 (void)soclose(rso); 171 free(fip, M_VNODE); 172 vp->v_fifoinfo = NULL; 173 return (error); 174 } 175 fip->fi_writesock = wso; 176 error = unp_connect2(wso, rso); 177 if (error) { 178 (void)soclose(wso); 179 (void)soclose(rso); 180 free(fip, M_VNODE); 181 vp->v_fifoinfo = NULL; 182 return (error); 183 } 184 fip->fi_readers = fip->fi_writers = 0; 185 wso->so_state |= SS_CANTRCVMORE; 186 rso->so_state |= SS_CANTSENDMORE; 187 } 188 error = 0; 189 if ((ap->a_mode & (FREAD|FWRITE)) == (FREAD|FWRITE)) { 190 if (fip->fi_readers == 0) { 191 fip->fi_writesock->so_state &= ~SS_CANTSENDMORE; 192 if (fip->fi_writers > 0) 193 wakeup((caddr_t)&fip->fi_writers); 194 } 195 if (fip->fi_writers == 0) { 196 fip->fi_readsock->so_state &= ~SS_CANTRCVMORE; 197 if (fip->fi_readers > 0) 198 wakeup((caddr_t)&fip->fi_readers); 199 } 200 fip->fi_readers++; 201 fip->fi_writers++; 202 } 203 else if (ap->a_mode & FREAD) { 204 fip->fi_readers++; 205 if (fip->fi_readers == 1) { 206 fip->fi_writesock->so_state &= ~SS_CANTSENDMORE; 207 if (fip->fi_writers > 0) 208 wakeup((caddr_t)&fip->fi_writers); 209 } 210 if (!(ap->a_mode & O_NONBLOCK)) 211 while (fip->fi_writers == 0) { 212 VOP_UNLOCK(vp); 213 error = tsleep((caddr_t)&fip->fi_readers, 214 PCATCH | PSOCK, openstr, 0); 215 VOP_LOCK(vp); 216 if (error) 217 break; 218 } 219 } 220 else { 221 fip->fi_writers++; 222 if (fip->fi_readers == 0 && (ap->a_mode & O_NONBLOCK)) { 223 error = ENXIO; 224 } else { 225 if (fip->fi_writers == 1) { 226 fip->fi_readsock->so_state &= ~SS_CANTRCVMORE; 227 if (fip->fi_readers > 0) 228 wakeup((caddr_t)&fip->fi_readers); 229 } 230 while (fip->fi_readers == 0) { 231 VOP_UNLOCK(vp); 232 error = tsleep((caddr_t)&fip->fi_writers, 233 PCATCH | PSOCK, openstr, 0); 234 VOP_LOCK(vp); 235 if (error) 236 break; 237 } 238 } 239 } 240 if (error) 241 VOP_CLOSE(vp, ap->a_mode, ap->a_cred, ap->a_p); 242 return (error); 243 } 244 245 /* 246 * Vnode op for read 247 */ 248 /* ARGSUSED */ 249 int 250 fifo_read(ap) 251 struct vop_read_args /* { 252 struct vnode *a_vp; 253 struct uio *a_uio; 254 int a_ioflag; 255 struct ucred *a_cred; 256 } */ *ap; 257 { 258 register struct uio *uio = ap->a_uio; 259 register struct socket *rso = ap->a_vp->v_fifoinfo->fi_readsock; 260 int error, startresid; 261 262 #ifdef DIAGNOSTIC 263 if (uio->uio_rw != UIO_READ) 264 panic("fifo_read mode"); 265 #endif 266 if (uio->uio_resid == 0) 267 return (0); 268 if (ap->a_ioflag & IO_NDELAY) 269 rso->so_state |= SS_NBIO; 270 startresid = uio->uio_resid; 271 VOP_UNLOCK(ap->a_vp); 272 error = soreceive(rso, (struct mbuf **)0, uio, 273 (struct mbuf **)0, (struct mbuf **)0, (int*)0); 274 VOP_LOCK(ap->a_vp); 275 /* 276 * Clear EOF indication after first such return. 277 */ 278 if (uio->uio_resid == startresid) 279 rso->so_state &= ~SS_CANTRCVMORE; 280 if (ap->a_ioflag & IO_NDELAY) 281 rso->so_state &= ~SS_NBIO; 282 return (error); 283 } 284 285 /* 286 * Vnode op for write 287 */ 288 /* ARGSUSED */ 289 int 290 fifo_write(ap) 291 struct vop_write_args /* { 292 struct vnode *a_vp; 293 struct uio *a_uio; 294 int a_ioflag; 295 struct ucred *a_cred; 296 } */ *ap; 297 { 298 struct socket *wso = ap->a_vp->v_fifoinfo->fi_writesock; 299 int error; 300 301 #ifdef DIAGNOSTIC 302 if (ap->a_uio->uio_rw != UIO_WRITE) 303 panic("fifo_write mode"); 304 #endif 305 if (ap->a_ioflag & IO_NDELAY) 306 wso->so_state |= SS_NBIO; 307 VOP_UNLOCK(ap->a_vp); 308 error = sosend(wso, (struct mbuf *)0, ap->a_uio, 0, (struct mbuf *)0, 0); 309 VOP_LOCK(ap->a_vp); 310 if (ap->a_ioflag & IO_NDELAY) 311 wso->so_state &= ~SS_NBIO; 312 return (error); 313 } 314 315 /* 316 * Device ioctl operation. 317 */ 318 /* ARGSUSED */ 319 int 320 fifo_ioctl(ap) 321 struct vop_ioctl_args /* { 322 struct vnode *a_vp; 323 int a_command; 324 caddr_t a_data; 325 int a_fflag; 326 struct ucred *a_cred; 327 struct proc *a_p; 328 } */ *ap; 329 { 330 struct file filetmp; 331 332 if (ap->a_command == FIONBIO) 333 return (0); 334 if (ap->a_fflag & FREAD) 335 filetmp.f_data = (caddr_t)ap->a_vp->v_fifoinfo->fi_readsock; 336 else 337 filetmp.f_data = (caddr_t)ap->a_vp->v_fifoinfo->fi_writesock; 338 return (soo_ioctl(&filetmp, ap->a_command, ap->a_data, ap->a_p)); 339 } 340 341 /* ARGSUSED */ 342 int 343 fifo_select(ap) 344 struct vop_select_args /* { 345 struct vnode *a_vp; 346 int a_which; 347 int a_fflags; 348 struct ucred *a_cred; 349 struct proc *a_p; 350 } */ *ap; 351 { 352 struct file filetmp; 353 354 if (ap->a_fflags & FREAD) 355 filetmp.f_data = (caddr_t)ap->a_vp->v_fifoinfo->fi_readsock; 356 else 357 filetmp.f_data = (caddr_t)ap->a_vp->v_fifoinfo->fi_writesock; 358 return (soo_select(&filetmp, ap->a_which, ap->a_p)); 359 } 360 361 /* 362 * This is a noop, simply returning what one has been given. 363 */ 364 int 365 fifo_bmap(ap) 366 struct vop_bmap_args /* { 367 struct vnode *a_vp; 368 daddr_t a_bn; 369 struct vnode **a_vpp; 370 daddr_t *a_bnp; 371 int *a_runp; 372 int *a_runb; 373 } */ *ap; 374 { 375 376 if (ap->a_vpp != NULL) 377 *ap->a_vpp = ap->a_vp; 378 if (ap->a_bnp != NULL) 379 *ap->a_bnp = ap->a_bn; 380 if (ap->a_runp != NULL) 381 *ap->a_runp = 0; 382 if (ap->a_runb != NULL) 383 *ap->a_runb = 0; 384 return (0); 385 } 386 387 /* 388 * At the moment we do not do any locking. 389 */ 390 /* ARGSUSED */ 391 static int 392 fifo_lock(ap) 393 struct vop_lock_args /* { 394 struct vnode *a_vp; 395 } */ *ap; 396 { 397 398 return (0); 399 } 400 401 /* ARGSUSED */ 402 static int 403 fifo_unlock(ap) 404 struct vop_unlock_args /* { 405 struct vnode *a_vp; 406 } */ *ap; 407 { 408 409 return (0); 410 } 411 412 /* 413 * Device close routine 414 */ 415 /* ARGSUSED */ 416 int 417 fifo_close(ap) 418 struct vop_close_args /* { 419 struct vnode *a_vp; 420 int a_fflag; 421 struct ucred *a_cred; 422 struct proc *a_p; 423 } */ *ap; 424 { 425 register struct vnode *vp = ap->a_vp; 426 register struct fifoinfo *fip = vp->v_fifoinfo; 427 int error1, error2; 428 429 if (ap->a_fflag & FWRITE) { 430 fip->fi_writers--; 431 if (fip->fi_writers == 0) 432 socantrcvmore(fip->fi_readsock); 433 } 434 if (ap->a_fflag & FREAD) { 435 fip->fi_readers--; 436 if (fip->fi_readers == 0) 437 socantsendmore(fip->fi_writesock); 438 } 439 if (vp->v_usecount > 1) 440 return (0); 441 error1 = soclose(fip->fi_readsock); 442 error2 = soclose(fip->fi_writesock); 443 FREE(fip, M_VNODE); 444 vp->v_fifoinfo = NULL; 445 if (error1) 446 return (error1); 447 return (error2); 448 } 449 450 451 /* 452 * Print out internal contents of a fifo vnode. 453 */ 454 int 455 fifo_printinfo(vp) 456 struct vnode *vp; 457 { 458 register struct fifoinfo *fip = vp->v_fifoinfo; 459 460 printf(", fifo with %ld readers and %ld writers", 461 fip->fi_readers, fip->fi_writers); 462 return (0); 463 } 464 465 /* 466 * Print out the contents of a fifo vnode. 467 */ 468 static int 469 fifo_print(ap) 470 struct vop_print_args /* { 471 struct vnode *a_vp; 472 } */ *ap; 473 { 474 475 printf("tag VT_NON"); 476 fifo_printinfo(ap->a_vp); 477 printf("\n"); 478 return (0); 479 } 480 481 /* 482 * Return POSIX pathconf information applicable to fifo's. 483 */ 484 int 485 fifo_pathconf(ap) 486 struct vop_pathconf_args /* { 487 struct vnode *a_vp; 488 int a_name; 489 int *a_retval; 490 } */ *ap; 491 { 492 493 switch (ap->a_name) { 494 case _PC_LINK_MAX: 495 *ap->a_retval = LINK_MAX; 496 return (0); 497 case _PC_PIPE_BUF: 498 *ap->a_retval = PIPE_BUF; 499 return (0); 500 case _PC_CHOWN_RESTRICTED: 501 *ap->a_retval = 1; 502 return (0); 503 default: 504 return (EINVAL); 505 } 506 /* NOTREACHED */ 507 } 508 509 /* 510 * Fifo failed operation 511 */ 512 static int 513 fifo_ebadf() 514 { 515 516 return (EBADF); 517 } 518 519 /* 520 * Fifo advisory byte-level locks. 521 */ 522 /* ARGSUSED */ 523 int 524 fifo_advlock(ap) 525 struct vop_advlock_args /* { 526 struct vnode *a_vp; 527 caddr_t a_id; 528 int a_op; 529 struct flock *a_fl; 530 int a_flags; 531 } */ *ap; 532 { 533 534 return (EOPNOTSUPP); 535 } 536 537 /* 538 * Fifo bad operation 539 */ 540 int 541 fifo_badop() 542 { 543 544 panic("fifo_badop called"); 545 /* NOTREACHED */ 546 } 547