fifo_vnops.c revision 1.23
1 /* $NetBSD: fifo_vnops.c,v 1.23 1997/05/18 12:19:29 kleink 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 if (error == EWOULDBLOCK && 272 ap->a_vp->v_fifoinfo->fi_writers == 0) 273 error = 0; 274 } 275 return (error); 276 } 277 278 /* 279 * Vnode op for write 280 */ 281 /* ARGSUSED */ 282 int 283 fifo_write(v) 284 void *v; 285 { 286 struct vop_write_args /* { 287 struct vnode *a_vp; 288 struct uio *a_uio; 289 int a_ioflag; 290 struct ucred *a_cred; 291 } */ *ap = v; 292 struct socket *wso = ap->a_vp->v_fifoinfo->fi_writesock; 293 int error; 294 295 #ifdef DIAGNOSTIC 296 if (ap->a_uio->uio_rw != UIO_WRITE) 297 panic("fifo_write mode"); 298 #endif 299 if (ap->a_ioflag & IO_NDELAY) 300 wso->so_state |= SS_NBIO; 301 VOP_UNLOCK(ap->a_vp); 302 error = sosend(wso, (struct mbuf *)0, ap->a_uio, 0, (struct mbuf *)0, 0); 303 VOP_LOCK(ap->a_vp); 304 if (ap->a_ioflag & IO_NDELAY) 305 wso->so_state &= ~SS_NBIO; 306 return (error); 307 } 308 309 /* 310 * Device ioctl operation. 311 */ 312 /* ARGSUSED */ 313 int 314 fifo_ioctl(v) 315 void *v; 316 { 317 struct vop_ioctl_args /* { 318 struct vnode *a_vp; 319 u_long a_command; 320 caddr_t a_data; 321 int a_fflag; 322 struct ucred *a_cred; 323 struct proc *a_p; 324 } */ *ap = v; 325 struct file filetmp; 326 int error; 327 328 if (ap->a_command == FIONBIO) 329 return (0); 330 if (ap->a_fflag & FREAD) { 331 filetmp.f_data = (caddr_t)ap->a_vp->v_fifoinfo->fi_readsock; 332 error = soo_ioctl(&filetmp, ap->a_command, ap->a_data, ap->a_p); 333 if (error) 334 return (error); 335 } 336 if (ap->a_fflag & FWRITE) { 337 filetmp.f_data = (caddr_t)ap->a_vp->v_fifoinfo->fi_writesock; 338 error = soo_ioctl(&filetmp, ap->a_command, ap->a_data, ap->a_p); 339 if (error) 340 return (error); 341 } 342 return (0); 343 } 344 345 /* ARGSUSED */ 346 int 347 fifo_poll(v) 348 void *v; 349 { 350 struct vop_poll_args /* { 351 struct vnode *a_vp; 352 int a_events; 353 struct proc *a_p; 354 } */ *ap = v; 355 struct file filetmp; 356 int revents = 0; 357 358 if (ap->a_events & (POLLIN | POLLPRI | POLLRDNORM | POLLRDBAND)) { 359 filetmp.f_data = (caddr_t)ap->a_vp->v_fifoinfo->fi_readsock; 360 if (filetmp.f_data) 361 revents |= soo_poll(&filetmp, ap->a_events, ap->a_p); 362 } 363 if (ap->a_events & (POLLOUT | POLLWRNORM | POLLWRBAND)) { 364 filetmp.f_data = (caddr_t)ap->a_vp->v_fifoinfo->fi_writesock; 365 if (filetmp.f_data) 366 revents |= soo_poll(&filetmp, ap->a_events, ap->a_p); 367 } 368 369 return (revents); 370 } 371 372 /* 373 * This is a noop, simply returning what one has been given. 374 */ 375 int 376 fifo_bmap(v) 377 void *v; 378 { 379 struct vop_bmap_args /* { 380 struct vnode *a_vp; 381 daddr_t a_bn; 382 struct vnode **a_vpp; 383 daddr_t *a_bnp; 384 } */ *ap = v; 385 386 if (ap->a_vpp != NULL) 387 *ap->a_vpp = ap->a_vp; 388 if (ap->a_bnp != NULL) 389 *ap->a_bnp = ap->a_bn; 390 return (0); 391 } 392 393 /* 394 * At the moment we do not do any locking. 395 */ 396 /* ARGSUSED */ 397 int 398 fifo_lock(v) 399 void *v; 400 { 401 return (0); 402 } 403 404 /* ARGSUSED */ 405 int 406 fifo_unlock(v) 407 void *v; 408 { 409 410 return (0); 411 } 412 413 /* 414 * Device close routine 415 */ 416 /* ARGSUSED */ 417 int 418 fifo_close(v) 419 void *v; 420 { 421 struct vop_close_args /* { 422 struct vnode *a_vp; 423 int a_fflag; 424 struct ucred *a_cred; 425 struct proc *a_p; 426 } */ *ap = v; 427 register struct vnode *vp = ap->a_vp; 428 register struct fifoinfo *fip = vp->v_fifoinfo; 429 int error1, error2; 430 431 if (ap->a_fflag & FREAD) { 432 if (--fip->fi_readers == 0) 433 socantsendmore(fip->fi_writesock); 434 } 435 if (ap->a_fflag & FWRITE) { 436 if (--fip->fi_writers == 0) 437 socantrcvmore(fip->fi_readsock); 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 * Print out the contents of a fifo vnode. 452 */ 453 int 454 fifo_print(v) 455 void *v; 456 { 457 struct vop_print_args /* { 458 struct vnode *a_vp; 459 } */ *ap = v; 460 461 printf("tag VT_NON"); 462 fifo_printinfo(ap->a_vp); 463 printf("\n"); 464 return 0; 465 } 466 467 /* 468 * Print out internal contents of a fifo vnode. 469 */ 470 void 471 fifo_printinfo(vp) 472 struct vnode *vp; 473 { 474 register struct fifoinfo *fip = vp->v_fifoinfo; 475 476 printf(", fifo with %ld readers and %ld writers", 477 fip->fi_readers, fip->fi_writers); 478 } 479 480 /* 481 * Return POSIX pathconf information applicable to fifo's. 482 */ 483 int 484 fifo_pathconf(v) 485 void *v; 486 { 487 struct vop_pathconf_args /* { 488 struct vnode *a_vp; 489 int a_name; 490 register_t *a_retval; 491 } */ *ap = v; 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
Indexes created Wed Sep 24 05:09:52 GMT 2025