fifo_vnops.c revision 1.19
1 /* $NetBSD: fifo_vnops.c,v 1.19 1996/09/01 23:48:04 mycroft 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 53 #include <miscfs/fifofs/fifo.h> 54 #include <miscfs/genfs/genfs.h> 55 56 /* 57 * This structure is associated with the FIFO vnode and stores 58 * the state associated with the FIFO. 59 */ 60 struct fifoinfo { 61 struct socket *fi_readsock; 62 struct socket *fi_writesock; 63 long fi_readers; 64 long fi_writers; 65 }; 66 67 int (**fifo_vnodeop_p) __P((void *)); 68 struct vnodeopv_entry_desc fifo_vnodeop_entries[] = { 69 { &vop_default_desc, vn_default_error }, 70 { &vop_lookup_desc, fifo_lookup }, /* lookup */ 71 { &vop_create_desc, fifo_create }, /* create */ 72 { &vop_mknod_desc, fifo_mknod }, /* mknod */ 73 { &vop_open_desc, fifo_open }, /* open */ 74 { &vop_close_desc, fifo_close }, /* close */ 75 { &vop_access_desc, fifo_access }, /* access */ 76 { &vop_getattr_desc, fifo_getattr }, /* getattr */ 77 { &vop_setattr_desc, fifo_setattr }, /* setattr */ 78 { &vop_read_desc, fifo_read }, /* read */ 79 { &vop_write_desc, fifo_write }, /* write */ 80 { &vop_lease_desc, fifo_lease_check }, /* lease */ 81 { &vop_ioctl_desc, fifo_ioctl }, /* ioctl */ 82 { &vop_select_desc, fifo_select }, /* select */ 83 { &vop_mmap_desc, fifo_mmap }, /* mmap */ 84 { &vop_fsync_desc, fifo_fsync }, /* fsync */ 85 { &vop_seek_desc, fifo_seek }, /* seek */ 86 { &vop_remove_desc, fifo_remove }, /* remove */ 87 { &vop_link_desc, fifo_link }, /* link */ 88 { &vop_rename_desc, fifo_rename }, /* rename */ 89 { &vop_mkdir_desc, fifo_mkdir }, /* mkdir */ 90 { &vop_rmdir_desc, fifo_rmdir }, /* rmdir */ 91 { &vop_symlink_desc, fifo_symlink }, /* symlink */ 92 { &vop_readdir_desc, fifo_readdir }, /* readdir */ 93 { &vop_readlink_desc, fifo_readlink }, /* readlink */ 94 { &vop_abortop_desc, fifo_abortop }, /* abortop */ 95 { &vop_inactive_desc, fifo_inactive }, /* inactive */ 96 { &vop_reclaim_desc, fifo_reclaim }, /* reclaim */ 97 { &vop_lock_desc, fifo_lock }, /* lock */ 98 { &vop_unlock_desc, fifo_unlock }, /* unlock */ 99 { &vop_bmap_desc, fifo_bmap }, /* bmap */ 100 { &vop_strategy_desc, fifo_strategy }, /* strategy */ 101 { &vop_print_desc, fifo_print }, /* print */ 102 { &vop_islocked_desc, fifo_islocked }, /* islocked */ 103 { &vop_pathconf_desc, fifo_pathconf }, /* pathconf */ 104 { &vop_advlock_desc, fifo_advlock }, /* advlock */ 105 { &vop_blkatoff_desc, fifo_blkatoff }, /* blkatoff */ 106 { &vop_valloc_desc, fifo_valloc }, /* valloc */ 107 { &vop_vfree_desc, fifo_vfree }, /* vfree */ 108 { &vop_truncate_desc, fifo_truncate }, /* truncate */ 109 { &vop_update_desc, fifo_update }, /* update */ 110 { &vop_bwrite_desc, fifo_bwrite }, /* bwrite */ 111 { (struct vnodeop_desc*)NULL, (int(*) __P((void *)))NULL } 112 }; 113 struct vnodeopv_desc fifo_vnodeop_opv_desc = 114 { &fifo_vnodeop_p, fifo_vnodeop_entries }; 115 116 /* 117 * Trivial lookup routine that always fails. 118 */ 119 /* ARGSUSED */ 120 int 121 fifo_lookup(v) 122 void *v; 123 { 124 struct vop_lookup_args /* { 125 struct vnode * a_dvp; 126 struct vnode ** a_vpp; 127 struct componentname * a_cnp; 128 } */ *ap = v; 129 130 *ap->a_vpp = NULL; 131 return (ENOTDIR); 132 } 133 134 /* 135 * Open called to set up a new instance of a fifo or 136 * to find an active instance of a fifo. 137 */ 138 /* ARGSUSED */ 139 int 140 fifo_open(v) 141 void *v; 142 { 143 struct vop_open_args /* { 144 struct vnode *a_vp; 145 int a_mode; 146 struct ucred *a_cred; 147 struct proc *a_p; 148 } */ *ap = v; 149 register struct vnode *vp = ap->a_vp; 150 register struct fifoinfo *fip; 151 struct socket *rso, *wso; 152 int error; 153 static char openstr[] = "fifo"; 154 155 if ((fip = vp->v_fifoinfo) == NULL) { 156 MALLOC(fip, struct fifoinfo *, sizeof(*fip), M_VNODE, M_WAITOK); 157 vp->v_fifoinfo = fip; 158 if ((error = socreate(AF_LOCAL, &rso, SOCK_STREAM, 0)) != 0) { 159 free(fip, M_VNODE); 160 vp->v_fifoinfo = NULL; 161 return (error); 162 } 163 fip->fi_readsock = rso; 164 if ((error = socreate(AF_LOCAL, &wso, SOCK_STREAM, 0)) != 0) { 165 (void)soclose(rso); 166 free(fip, M_VNODE); 167 vp->v_fifoinfo = NULL; 168 return (error); 169 } 170 fip->fi_writesock = wso; 171 if ((error = unp_connect2(wso, rso)) != 0) { 172 (void)soclose(wso); 173 (void)soclose(rso); 174 free(fip, M_VNODE); 175 vp->v_fifoinfo = NULL; 176 return (error); 177 } 178 fip->fi_readers = fip->fi_writers = 0; 179 wso->so_state |= SS_CANTRCVMORE; 180 rso->so_state |= SS_CANTSENDMORE; 181 } 182 if (ap->a_mode & FREAD) { 183 if (fip->fi_readers++ == 0) { 184 fip->fi_writesock->so_state &= ~SS_CANTSENDMORE; 185 if (fip->fi_writers > 0) 186 wakeup((caddr_t)&fip->fi_writers); 187 } 188 } 189 if (ap->a_mode & FWRITE) { 190 if (fip->fi_writers++ == 0) { 191 fip->fi_readsock->so_state &= ~SS_CANTRCVMORE; 192 if (fip->fi_readers > 0) 193 wakeup((caddr_t)&fip->fi_readers); 194 } 195 } 196 if (ap->a_mode & FREAD) { 197 if (ap->a_mode & O_NONBLOCK) { 198 } else { 199 while (fip->fi_writers == 0) { 200 VOP_UNLOCK(vp); 201 error = tsleep((caddr_t)&fip->fi_readers, 202 PCATCH | PSOCK, openstr, 0); 203 VOP_LOCK(vp); 204 if (error) 205 goto bad; 206 } 207 } 208 } 209 if (ap->a_mode & FWRITE) { 210 if (ap->a_mode & O_NONBLOCK) { 211 if (fip->fi_readers == 0) { 212 error = ENXIO; 213 goto bad; 214 } 215 } else { 216 while (fip->fi_readers == 0) { 217 VOP_UNLOCK(vp); 218 error = tsleep((caddr_t)&fip->fi_writers, 219 PCATCH | PSOCK, openstr, 0); 220 VOP_LOCK(vp); 221 if (error) 222 goto bad; 223 } 224 } 225 } 226 return (0); 227 bad: 228 VOP_CLOSE(vp, ap->a_mode, ap->a_cred, ap->a_p); 229 return (error); 230 } 231 232 /* 233 * Vnode op for read 234 */ 235 /* ARGSUSED */ 236 int 237 fifo_read(v) 238 void *v; 239 { 240 struct vop_read_args /* { 241 struct vnode *a_vp; 242 struct uio *a_uio; 243 int a_ioflag; 244 struct ucred *a_cred; 245 } */ *ap = v; 246 register struct uio *uio = ap->a_uio; 247 register struct socket *rso = ap->a_vp->v_fifoinfo->fi_readsock; 248 int error, startresid; 249 250 #ifdef DIAGNOSTIC 251 if (uio->uio_rw != UIO_READ) 252 panic("fifo_read mode"); 253 #endif 254 if (uio->uio_resid == 0) 255 return (0); 256 if (ap->a_ioflag & IO_NDELAY) 257 rso->so_state |= SS_NBIO; 258 startresid = uio->uio_resid; 259 VOP_UNLOCK(ap->a_vp); 260 error = soreceive(rso, (struct mbuf **)0, uio, (struct mbuf **)0, 261 (struct mbuf **)0, (int *)0); 262 VOP_LOCK(ap->a_vp); 263 /* 264 * Clear EOF indication after first such return. 265 */ 266 if (uio->uio_resid == startresid) 267 rso->so_state &= ~SS_CANTRCVMORE; 268 if (ap->a_ioflag & IO_NDELAY) 269 rso->so_state &= ~SS_NBIO; 270 return (error); 271 } 272 273 /* 274 * Vnode op for write 275 */ 276 /* ARGSUSED */ 277 int 278 fifo_write(v) 279 void *v; 280 { 281 struct vop_write_args /* { 282 struct vnode *a_vp; 283 struct uio *a_uio; 284 int a_ioflag; 285 struct ucred *a_cred; 286 } */ *ap = v; 287 struct socket *wso = ap->a_vp->v_fifoinfo->fi_writesock; 288 int error; 289 290 #ifdef DIAGNOSTIC 291 if (ap->a_uio->uio_rw != UIO_WRITE) 292 panic("fifo_write mode"); 293 #endif 294 if (ap->a_ioflag & IO_NDELAY) 295 wso->so_state |= SS_NBIO; 296 VOP_UNLOCK(ap->a_vp); 297 error = sosend(wso, (struct mbuf *)0, ap->a_uio, 0, (struct mbuf *)0, 0); 298 VOP_LOCK(ap->a_vp); 299 if (ap->a_ioflag & IO_NDELAY) 300 wso->so_state &= ~SS_NBIO; 301 return (error); 302 } 303 304 /* 305 * Device ioctl operation. 306 */ 307 /* ARGSUSED */ 308 int 309 fifo_ioctl(v) 310 void *v; 311 { 312 struct vop_ioctl_args /* { 313 struct vnode *a_vp; 314 u_long a_command; 315 caddr_t a_data; 316 int a_fflag; 317 struct ucred *a_cred; 318 struct proc *a_p; 319 } */ *ap = v; 320 struct file filetmp; 321 int error; 322 323 if (ap->a_command == FIONBIO) 324 return (0); 325 if (ap->a_fflag & FREAD) { 326 filetmp.f_data = (caddr_t)ap->a_vp->v_fifoinfo->fi_readsock; 327 error = soo_ioctl(&filetmp, ap->a_command, ap->a_data, ap->a_p); 328 if (error) 329 return (error); 330 } 331 if (ap->a_fflag & FWRITE) { 332 filetmp.f_data = (caddr_t)ap->a_vp->v_fifoinfo->fi_writesock; 333 error = soo_ioctl(&filetmp, ap->a_command, ap->a_data, ap->a_p); 334 if (error) 335 return (error); 336 } 337 return (0); 338 } 339 340 /* ARGSUSED */ 341 int 342 fifo_select(v) 343 void *v; 344 { 345 struct vop_select_args /* { 346 struct vnode *a_vp; 347 int a_which; 348 int a_fflags; 349 struct ucred *a_cred; 350 struct proc *a_p; 351 } */ *ap = v; 352 struct file filetmp; 353 int ready = 0; 354 355 if (ap->a_fflags & FREAD) { 356 filetmp.f_data = (caddr_t)ap->a_vp->v_fifoinfo->fi_readsock; 357 ready |= soo_select(&filetmp, ap->a_which, ap->a_p); 358 } 359 if (ap->a_fflags & FWRITE) { 360 filetmp.f_data = (caddr_t)ap->a_vp->v_fifoinfo->fi_writesock; 361 ready |= soo_select(&filetmp, ap->a_which, ap->a_p); 362 } 363 return (ready); 364 } 365 366 /* 367 * This is a noop, simply returning what one has been given. 368 */ 369 int 370 fifo_bmap(v) 371 void *v; 372 { 373 struct vop_bmap_args /* { 374 struct vnode *a_vp; 375 daddr_t a_bn; 376 struct vnode **a_vpp; 377 daddr_t *a_bnp; 378 } */ *ap = v; 379 380 if (ap->a_vpp != NULL) 381 *ap->a_vpp = ap->a_vp; 382 if (ap->a_bnp != NULL) 383 *ap->a_bnp = ap->a_bn; 384 return (0); 385 } 386 387 /* 388 * At the moment we do not do any locking. 389 */ 390 /* ARGSUSED */ 391 int 392 fifo_lock(v) 393 void *v; 394 { 395 return (0); 396 } 397 398 /* ARGSUSED */ 399 int 400 fifo_unlock(v) 401 void *v; 402 { 403 404 return (0); 405 } 406 407 /* 408 * Device close routine 409 */ 410 /* ARGSUSED */ 411 int 412 fifo_close(v) 413 void *v; 414 { 415 struct vop_close_args /* { 416 struct vnode *a_vp; 417 int a_fflag; 418 struct ucred *a_cred; 419 struct proc *a_p; 420 } */ *ap = v; 421 register struct vnode *vp = ap->a_vp; 422 register struct fifoinfo *fip = vp->v_fifoinfo; 423 int error1, error2; 424 425 if (ap->a_fflag & FREAD) { 426 if (--fip->fi_readers == 0) 427 socantsendmore(fip->fi_writesock); 428 } 429 if (ap->a_fflag & FWRITE) { 430 if (--fip->fi_writers == 0) 431 socantrcvmore(fip->fi_readsock); 432 } 433 if (vp->v_usecount > 1) 434 return (0); 435 error1 = soclose(fip->fi_readsock); 436 error2 = soclose(fip->fi_writesock); 437 FREE(fip, M_VNODE); 438 vp->v_fifoinfo = NULL; 439 if (error1) 440 return (error1); 441 return (error2); 442 } 443 444 /* 445 * Print out the contents of a fifo vnode. 446 */ 447 int 448 fifo_print(v) 449 void *v; 450 { 451 struct vop_print_args /* { 452 struct vnode *a_vp; 453 } */ *ap = v; 454 455 printf("tag VT_NON"); 456 fifo_printinfo(ap->a_vp); 457 printf("\n"); 458 return 0; 459 } 460 461 /* 462 * Print out internal contents of a fifo vnode. 463 */ 464 void 465 fifo_printinfo(vp) 466 struct vnode *vp; 467 { 468 register struct fifoinfo *fip = vp->v_fifoinfo; 469 470 printf(", fifo with %ld readers and %ld writers", 471 fip->fi_readers, fip->fi_writers); 472 } 473 474 /* 475 * Return POSIX pathconf information applicable to fifo's. 476 */ 477 int 478 fifo_pathconf(v) 479 void *v; 480 { 481 struct vop_pathconf_args /* { 482 struct vnode *a_vp; 483 int a_name; 484 register_t *a_retval; 485 } */ *ap = v; 486 487 switch (ap->a_name) { 488 case _PC_LINK_MAX: 489 *ap->a_retval = LINK_MAX; 490 return (0); 491 case _PC_PIPE_BUF: 492 *ap->a_retval = PIPE_BUF; 493 return (0); 494 case _PC_CHOWN_RESTRICTED: 495 *ap->a_retval = 1; 496 return (0); 497 default: 498 return (EINVAL); 499 } 500 /* NOTREACHED */ 501 } 502
Indexes created Thu Sep 25 08:09:54 GMT 2025