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 1.5 1994/09/22 19:38:07 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/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 <miscfs/fifofs/fifo.h> 52 53 /* 54 * This structure is associated with the FIFO vnode and stores 55 * the state associated with the FIFO. 56 */ 57 struct fifoinfo { 58 struct socket *fi_readsock; 59 struct socket *fi_writesock; 60 long fi_readers; 61 long fi_writers; 62 }; 63 64 int (**fifo_vnodeop_p)(); 65 struct vnodeopv_entry_desc fifo_vnodeop_entries[] = { 66 { &vop_default_desc, vn_default_error }, 67 { &vop_lookup_desc, fifo_lookup }, /* lookup */ 68 { &vop_create_desc, fifo_create }, /* create */ 69 { &vop_mknod_desc, fifo_mknod }, /* mknod */ 70 { &vop_open_desc, fifo_open }, /* open */ 71 { &vop_close_desc, fifo_close }, /* close */ 72 { &vop_access_desc, fifo_access }, /* access */ 73 { &vop_getattr_desc, fifo_getattr }, /* getattr */ 74 { &vop_setattr_desc, fifo_setattr }, /* setattr */ 75 { &vop_read_desc, fifo_read }, /* read */ 76 { &vop_write_desc, fifo_write }, /* write */ 77 { &vop_ioctl_desc, fifo_ioctl }, /* ioctl */ 78 { &vop_select_desc, fifo_select }, /* select */ 79 { &vop_mmap_desc, fifo_mmap }, /* mmap */ 80 { &vop_fsync_desc, fifo_fsync }, /* fsync */ 81 { &vop_seek_desc, fifo_seek }, /* seek */ 82 { &vop_remove_desc, fifo_remove }, /* remove */ 83 { &vop_link_desc, fifo_link }, /* link */ 84 { &vop_rename_desc, fifo_rename }, /* rename */ 85 { &vop_mkdir_desc, fifo_mkdir }, /* mkdir */ 86 { &vop_rmdir_desc, fifo_rmdir }, /* rmdir */ 87 { &vop_symlink_desc, fifo_symlink }, /* symlink */ 88 { &vop_readdir_desc, fifo_readdir }, /* readdir */ 89 { &vop_readlink_desc, fifo_readlink }, /* readlink */ 90 { &vop_abortop_desc, fifo_abortop }, /* abortop */ 91 { &vop_inactive_desc, fifo_inactive }, /* inactive */ 92 { &vop_reclaim_desc, fifo_reclaim }, /* reclaim */ 93 { &vop_lock_desc, fifo_lock }, /* lock */ 94 { &vop_unlock_desc, fifo_unlock }, /* unlock */ 95 { &vop_bmap_desc, fifo_bmap }, /* bmap */ 96 { &vop_strategy_desc, fifo_strategy }, /* strategy */ 97 { &vop_print_desc, fifo_print }, /* print */ 98 { &vop_islocked_desc, fifo_islocked }, /* islocked */ 99 { &vop_pathconf_desc, fifo_pathconf }, /* pathconf */ 100 { &vop_advlock_desc, fifo_advlock }, /* advlock */ 101 { &vop_blkatoff_desc, fifo_blkatoff }, /* blkatoff */ 102 { &vop_valloc_desc, fifo_valloc }, /* valloc */ 103 { &vop_vfree_desc, fifo_vfree }, /* vfree */ 104 { &vop_truncate_desc, fifo_truncate }, /* truncate */ 105 { &vop_update_desc, fifo_update }, /* update */ 106 { &vop_bwrite_desc, fifo_bwrite }, /* bwrite */ 107 { (struct vnodeop_desc*)NULL, (int(*)())NULL } 108 }; 109 struct vnodeopv_desc fifo_vnodeop_opv_desc = 110 { &fifo_vnodeop_p, fifo_vnodeop_entries }; 111 112 VNODEOP_SET(fifo_vnodeop_opv_desc); 113 114 /* 115 * Trivial lookup routine that always fails. 116 */ 117 /* ARGSUSED */ 118 int 119 fifo_lookup(ap) 120 struct vop_lookup_args /* { 121 struct vnode * a_dvp; 122 struct vnode ** a_vpp; 123 struct componentname * a_cnp; 124 } */ *ap; 125 { 126 127 *ap->a_vpp = NULL; 128 return (ENOTDIR); 129 } 130 131 /* 132 * Open called to set up a new instance of a fifo or 133 * to find an active instance of a fifo. 134 */ 135 /* ARGSUSED */ 136 int 137 fifo_open(ap) 138 struct vop_open_args /* { 139 struct vnode *a_vp; 140 int a_mode; 141 struct ucred *a_cred; 142 struct proc *a_p; 143 } */ *ap; 144 { 145 register struct vnode *vp = ap->a_vp; 146 register struct fifoinfo *fip; 147 struct socket *rso, *wso; 148 int error; 149 static char openstr[] = "fifo"; 150 151 if ((ap->a_mode & (FREAD|FWRITE)) == (FREAD|FWRITE)) 152 return (EINVAL); 153 if ((fip = vp->v_fifoinfo) == NULL) { 154 MALLOC(fip, struct fifoinfo *, sizeof(*fip), M_VNODE, M_WAITOK); 155 vp->v_fifoinfo = fip; 156 error = socreate(AF_UNIX, &rso, SOCK_STREAM, 0); 157 if (error) { 158 free(fip, M_VNODE); 159 vp->v_fifoinfo = NULL; 160 return (error); 161 } 162 fip->fi_readsock = rso; 163 error = socreate(AF_UNIX, &wso, SOCK_STREAM, 0); 164 if (error) { 165 (void)soclose(rso); 166 free(fip, M_VNODE); 167 vp->v_fifoinfo = NULL; 168 return (error); 169 } 170 fip->fi_writesock = wso; 171 error = unp_connect2(wso, rso); 172 if (error) { 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 error = 0; 184 if (ap->a_mode & FREAD) { 185 fip->fi_readers++; 186 if (fip->fi_readers == 1) { 187 fip->fi_writesock->so_state &= ~SS_CANTSENDMORE; 188 if (fip->fi_writers > 0) 189 wakeup((caddr_t)&fip->fi_writers); 190 } 191 if (ap->a_mode & O_NONBLOCK) 192 return (0); 193 while (fip->fi_writers == 0) { 194 VOP_UNLOCK(vp); 195 error = tsleep((caddr_t)&fip->fi_readers, 196 PCATCH | PSOCK, openstr, 0); 197 VOP_LOCK(vp); 198 if (error) 199 break; 200 } 201 } else { 202 fip->fi_writers++; 203 if (fip->fi_readers == 0 && (ap->a_mode & O_NONBLOCK)) { 204 error = ENXIO; 205 } else { 206 if (fip->fi_writers == 1) { 207 fip->fi_readsock->so_state &= ~SS_CANTRCVMORE; 208 if (fip->fi_readers > 0) 209 wakeup((caddr_t)&fip->fi_readers); 210 } 211 while (fip->fi_readers == 0) { 212 VOP_UNLOCK(vp); 213 error = tsleep((caddr_t)&fip->fi_writers, 214 PCATCH | PSOCK, openstr, 0); 215 VOP_LOCK(vp); 216 if (error) 217 break; 218 } 219 } 220 } 221 if (error) 222 VOP_CLOSE(vp, ap->a_mode, ap->a_cred, ap->a_p); 223 return (error); 224 } 225 226 /* 227 * Vnode op for read 228 */ 229 /* ARGSUSED */ 230 int 231 fifo_read(ap) 232 struct vop_read_args /* { 233 struct vnode *a_vp; 234 struct uio *a_uio; 235 int a_ioflag; 236 struct ucred *a_cred; 237 } */ *ap; 238 { 239 register struct uio *uio = ap->a_uio; 240 register struct socket *rso = ap->a_vp->v_fifoinfo->fi_readsock; 241 int error, startresid; 242 243 #ifdef DIAGNOSTIC 244 if (uio->uio_rw != UIO_READ) 245 panic("fifo_read mode"); 246 #endif 247 if (uio->uio_resid == 0) 248 return (0); 249 if (ap->a_ioflag & IO_NDELAY) 250 rso->so_state |= SS_NBIO; 251 startresid = uio->uio_resid; 252 VOP_UNLOCK(ap->a_vp); 253 error = soreceive(rso, (struct mbuf **)0, uio, 254 (struct mbuf **)0, (struct mbuf **)0, (int*)0); 255 VOP_LOCK(ap->a_vp); 256 /* 257 * Clear EOF indication after first such return. 258 */ 259 if (uio->uio_resid == startresid) 260 rso->so_state &= ~SS_CANTRCVMORE; 261 if (ap->a_ioflag & IO_NDELAY) 262 rso->so_state &= ~SS_NBIO; 263 return (error); 264 } 265 266 /* 267 * Vnode op for write 268 */ 269 /* ARGSUSED */ 270 int 271 fifo_write(ap) 272 struct vop_write_args /* { 273 struct vnode *a_vp; 274 struct uio *a_uio; 275 int a_ioflag; 276 struct ucred *a_cred; 277 } */ *ap; 278 { 279 struct socket *wso = ap->a_vp->v_fifoinfo->fi_writesock; 280 int error; 281 282 #ifdef DIAGNOSTIC 283 if (ap->a_uio->uio_rw != UIO_WRITE) 284 panic("fifo_write mode"); 285 #endif 286 if (ap->a_ioflag & IO_NDELAY) 287 wso->so_state |= SS_NBIO; 288 VOP_UNLOCK(ap->a_vp); 289 error = sosend(wso, (struct mbuf *)0, ap->a_uio, 0, (struct mbuf *)0, 0); 290 VOP_LOCK(ap->a_vp); 291 if (ap->a_ioflag & IO_NDELAY) 292 wso->so_state &= ~SS_NBIO; 293 return (error); 294 } 295 296 /* 297 * Device ioctl operation. 298 */ 299 /* ARGSUSED */ 300 int 301 fifo_ioctl(ap) 302 struct vop_ioctl_args /* { 303 struct vnode *a_vp; 304 int a_command; 305 caddr_t a_data; 306 int a_fflag; 307 struct ucred *a_cred; 308 struct proc *a_p; 309 } */ *ap; 310 { 311 struct file filetmp; 312 313 if (ap->a_command == FIONBIO) 314 return (0); 315 if (ap->a_fflag & FREAD) 316 filetmp.f_data = (caddr_t)ap->a_vp->v_fifoinfo->fi_readsock; 317 else 318 filetmp.f_data = (caddr_t)ap->a_vp->v_fifoinfo->fi_writesock; 319 return (soo_ioctl(&filetmp, ap->a_command, ap->a_data, ap->a_p)); 320 } 321 322 /* ARGSUSED */ 323 int 324 fifo_select(ap) 325 struct vop_select_args /* { 326 struct vnode *a_vp; 327 int a_which; 328 int a_fflags; 329 struct ucred *a_cred; 330 struct proc *a_p; 331 } */ *ap; 332 { 333 struct file filetmp; 334 335 if (ap->a_fflags & FREAD) 336 filetmp.f_data = (caddr_t)ap->a_vp->v_fifoinfo->fi_readsock; 337 else 338 filetmp.f_data = (caddr_t)ap->a_vp->v_fifoinfo->fi_writesock; 339 return (soo_select(&filetmp, ap->a_which, ap->a_p)); 340 } 341 342 /* 343 * This is a noop, simply returning what one has been given. 344 */ 345 int 346 fifo_bmap(ap) 347 struct vop_bmap_args /* { 348 struct vnode *a_vp; 349 daddr_t a_bn; 350 struct vnode **a_vpp; 351 daddr_t *a_bnp; 352 } */ *ap; 353 { 354 355 if (ap->a_vpp != NULL) 356 *ap->a_vpp = ap->a_vp; 357 if (ap->a_bnp != NULL) 358 *ap->a_bnp = ap->a_bn; 359 return (0); 360 } 361 362 /* 363 * At the moment we do not do any locking. 364 */ 365 /* ARGSUSED */ 366 int 367 fifo_lock(ap) 368 struct vop_lock_args /* { 369 struct vnode *a_vp; 370 } */ *ap; 371 { 372 373 return (0); 374 } 375 376 /* ARGSUSED */ 377 int 378 fifo_unlock(ap) 379 struct vop_unlock_args /* { 380 struct vnode *a_vp; 381 } */ *ap; 382 { 383 384 return (0); 385 } 386 387 /* 388 * Device close routine 389 */ 390 /* ARGSUSED */ 391 int 392 fifo_close(ap) 393 struct vop_close_args /* { 394 struct vnode *a_vp; 395 int a_fflag; 396 struct ucred *a_cred; 397 struct proc *a_p; 398 } */ *ap; 399 { 400 register struct vnode *vp = ap->a_vp; 401 register struct fifoinfo *fip = vp->v_fifoinfo; 402 int error1, error2; 403 404 if (ap->a_fflag & FWRITE) { 405 fip->fi_writers--; 406 if (fip->fi_writers == 0) 407 socantrcvmore(fip->fi_readsock); 408 } else { 409 fip->fi_readers--; 410 if (fip->fi_readers == 0) 411 socantsendmore(fip->fi_writesock); 412 } 413 if (vp->v_usecount > 1) 414 return (0); 415 error1 = soclose(fip->fi_readsock); 416 error2 = soclose(fip->fi_writesock); 417 FREE(fip, M_VNODE); 418 vp->v_fifoinfo = NULL; 419 if (error1) 420 return (error1); 421 return (error2); 422 } 423 424 425 /* 426 * Print out internal contents of a fifo vnode. 427 */ 428 int 429 fifo_printinfo(vp) 430 struct vnode *vp; 431 { 432 register struct fifoinfo *fip = vp->v_fifoinfo; 433 434 printf(", fifo with %ld readers and %ld writers", 435 fip->fi_readers, fip->fi_writers); 436 return (0); 437 } 438 439 /* 440 * Print out the contents of a fifo vnode. 441 */ 442 int 443 fifo_print(ap) 444 struct vop_print_args /* { 445 struct vnode *a_vp; 446 } */ *ap; 447 { 448 449 printf("tag VT_NON"); 450 fifo_printinfo(ap->a_vp); 451 printf("\n"); 452 return (0); 453 } 454 455 /* 456 * Return POSIX pathconf information applicable to fifo's. 457 */ 458 int 459 fifo_pathconf(ap) 460 struct vop_pathconf_args /* { 461 struct vnode *a_vp; 462 int a_name; 463 int *a_retval; 464 } */ *ap; 465 { 466 467 switch (ap->a_name) { 468 case _PC_LINK_MAX: 469 *ap->a_retval = LINK_MAX; 470 return (0); 471 case _PC_PIPE_BUF: 472 *ap->a_retval = PIPE_BUF; 473 return (0); 474 case _PC_CHOWN_RESTRICTED: 475 *ap->a_retval = 1; 476 return (0); 477 default: 478 return (EINVAL); 479 } 480 /* NOTREACHED */ 481 } 482 483 /* 484 * Fifo failed operation 485 */ 486 int 487 fifo_ebadf() 488 { 489 490 return (EBADF); 491 } 492 493 /* 494 * Fifo advisory byte-level locks. 495 */ 496 /* ARGSUSED */ 497 int 498 fifo_advlock(ap) 499 struct vop_advlock_args /* { 500 struct vnode *a_vp; 501 caddr_t a_id; 502 int a_op; 503 struct flock *a_fl; 504 int a_flags; 505 } */ *ap; 506 { 507 508 return (EOPNOTSUPP); 509 } 510 511 /* 512 * Fifo bad operation 513 */ 514 int 515 fifo_badop() 516 { 517 518 panic("fifo_badop called"); 519 /* NOTREACHED */ 520 } 521