1 /* 2 * Copyright (c) 1990, 1993, 1995 3 * The Regents of the University of California. All rights reserved. 4 * 5 * %sccs.include.redist.c% 6 * 7 * @(#)fifo_vnops.c 8.6 (Berkeley) 02/06/95 8 */ 9 10 #include <sys/param.h> 11 #include <sys/proc.h> 12 #include <sys/time.h> 13 #include <sys/namei.h> 14 #include <sys/vnode.h> 15 #include <sys/socket.h> 16 #include <sys/socketvar.h> 17 #include <sys/stat.h> 18 #include <sys/systm.h> 19 #include <sys/ioctl.h> 20 #include <sys/file.h> 21 #include <sys/errno.h> 22 #include <sys/malloc.h> 23 #include <miscfs/fifofs/fifo.h> 24 25 /* 26 * This structure is associated with the FIFO vnode and stores 27 * the state associated with the FIFO. 28 */ 29 struct fifoinfo { 30 struct socket *fi_readsock; 31 struct socket *fi_writesock; 32 long fi_readers; 33 long fi_writers; 34 }; 35 36 int (**fifo_vnodeop_p)(); 37 struct vnodeopv_entry_desc fifo_vnodeop_entries[] = { 38 { &vop_default_desc, vn_default_error }, 39 { &vop_lookup_desc, fifo_lookup }, /* lookup */ 40 { &vop_create_desc, fifo_create }, /* create */ 41 { &vop_mknod_desc, fifo_mknod }, /* mknod */ 42 { &vop_open_desc, fifo_open }, /* open */ 43 { &vop_close_desc, fifo_close }, /* close */ 44 { &vop_access_desc, fifo_access }, /* access */ 45 { &vop_getattr_desc, fifo_getattr }, /* getattr */ 46 { &vop_setattr_desc, fifo_setattr }, /* setattr */ 47 { &vop_read_desc, fifo_read }, /* read */ 48 { &vop_write_desc, fifo_write }, /* write */ 49 { &vop_lease_desc, fifo_lease_check }, /* lease */ 50 { &vop_ioctl_desc, fifo_ioctl }, /* ioctl */ 51 { &vop_select_desc, fifo_select }, /* select */ 52 { &vop_mmap_desc, fifo_mmap }, /* mmap */ 53 { &vop_fsync_desc, fifo_fsync }, /* fsync */ 54 { &vop_seek_desc, fifo_seek }, /* seek */ 55 { &vop_remove_desc, fifo_remove }, /* remove */ 56 { &vop_link_desc, fifo_link }, /* link */ 57 { &vop_rename_desc, fifo_rename }, /* rename */ 58 { &vop_mkdir_desc, fifo_mkdir }, /* mkdir */ 59 { &vop_rmdir_desc, fifo_rmdir }, /* rmdir */ 60 { &vop_symlink_desc, fifo_symlink }, /* symlink */ 61 { &vop_readdir_desc, fifo_readdir }, /* readdir */ 62 { &vop_readlink_desc, fifo_readlink }, /* readlink */ 63 { &vop_abortop_desc, fifo_abortop }, /* abortop */ 64 { &vop_inactive_desc, fifo_inactive }, /* inactive */ 65 { &vop_reclaim_desc, fifo_reclaim }, /* reclaim */ 66 { &vop_lock_desc, fifo_lock }, /* lock */ 67 { &vop_unlock_desc, fifo_unlock }, /* unlock */ 68 { &vop_bmap_desc, fifo_bmap }, /* bmap */ 69 { &vop_strategy_desc, fifo_strategy }, /* strategy */ 70 { &vop_print_desc, fifo_print }, /* print */ 71 { &vop_islocked_desc, fifo_islocked }, /* islocked */ 72 { &vop_pathconf_desc, fifo_pathconf }, /* pathconf */ 73 { &vop_advlock_desc, fifo_advlock }, /* advlock */ 74 { &vop_blkatoff_desc, fifo_blkatoff }, /* blkatoff */ 75 { &vop_valloc_desc, fifo_valloc }, /* valloc */ 76 { &vop_vfree_desc, fifo_vfree }, /* vfree */ 77 { &vop_truncate_desc, fifo_truncate }, /* truncate */ 78 { &vop_update_desc, fifo_update }, /* update */ 79 { &vop_bwrite_desc, fifo_bwrite }, /* bwrite */ 80 { (struct vnodeop_desc*)NULL, (int(*)())NULL } 81 }; 82 struct vnodeopv_desc fifo_vnodeop_opv_desc = 83 { &fifo_vnodeop_p, fifo_vnodeop_entries }; 84 85 /* 86 * Trivial lookup routine that always fails. 87 */ 88 /* ARGSUSED */ 89 fifo_lookup(ap) 90 struct vop_lookup_args /* { 91 struct vnode * a_dvp; 92 struct vnode ** a_vpp; 93 struct componentname * a_cnp; 94 } */ *ap; 95 { 96 97 *ap->a_vpp = NULL; 98 return (ENOTDIR); 99 } 100 101 /* 102 * Open called to set up a new instance of a fifo or 103 * to find an active instance of a fifo. 104 */ 105 /* ARGSUSED */ 106 fifo_open(ap) 107 struct vop_open_args /* { 108 struct vnode *a_vp; 109 int a_mode; 110 struct ucred *a_cred; 111 struct proc *a_p; 112 } */ *ap; 113 { 114 register struct vnode *vp = ap->a_vp; 115 register struct fifoinfo *fip; 116 struct socket *rso, *wso; 117 int error; 118 static char openstr[] = "fifo"; 119 120 if ((ap->a_mode & (FREAD|FWRITE)) == (FREAD|FWRITE)) 121 return (EINVAL); 122 if ((fip = vp->v_fifoinfo) == NULL) { 123 MALLOC(fip, struct fifoinfo *, sizeof(*fip), M_VNODE, M_WAITOK); 124 vp->v_fifoinfo = fip; 125 if (error = socreate(AF_LOCAL, &rso, SOCK_STREAM, 0)) { 126 free(fip, M_VNODE); 127 vp->v_fifoinfo = NULL; 128 return (error); 129 } 130 fip->fi_readsock = rso; 131 if (error = socreate(AF_LOCAL, &wso, SOCK_STREAM, 0)) { 132 (void)soclose(rso); 133 free(fip, M_VNODE); 134 vp->v_fifoinfo = NULL; 135 return (error); 136 } 137 fip->fi_writesock = wso; 138 if (error = unp_connect2(wso, rso)) { 139 (void)soclose(wso); 140 (void)soclose(rso); 141 free(fip, M_VNODE); 142 vp->v_fifoinfo = NULL; 143 return (error); 144 } 145 fip->fi_readers = fip->fi_writers = 0; 146 wso->so_state |= SS_CANTRCVMORE; 147 rso->so_state |= SS_CANTSENDMORE; 148 } 149 error = 0; 150 if (ap->a_mode & FREAD) { 151 fip->fi_readers++; 152 if (fip->fi_readers == 1) { 153 fip->fi_writesock->so_state &= ~SS_CANTSENDMORE; 154 if (fip->fi_writers > 0) 155 wakeup((caddr_t)&fip->fi_writers); 156 } 157 if (ap->a_mode & O_NONBLOCK) 158 return (0); 159 while (fip->fi_writers == 0) { 160 VOP_UNLOCK(vp); 161 error = tsleep((caddr_t)&fip->fi_readers, 162 PCATCH | PSOCK, openstr, 0); 163 VOP_LOCK(vp); 164 if (error) 165 break; 166 } 167 } else { 168 fip->fi_writers++; 169 if (fip->fi_readers == 0 && (ap->a_mode & O_NONBLOCK)) { 170 error = ENXIO; 171 } else { 172 if (fip->fi_writers == 1) { 173 fip->fi_readsock->so_state &= ~SS_CANTRCVMORE; 174 if (fip->fi_readers > 0) 175 wakeup((caddr_t)&fip->fi_readers); 176 } 177 while (fip->fi_readers == 0) { 178 VOP_UNLOCK(vp); 179 error = tsleep((caddr_t)&fip->fi_writers, 180 PCATCH | PSOCK, openstr, 0); 181 VOP_LOCK(vp); 182 if (error) 183 break; 184 } 185 } 186 } 187 if (error) 188 VOP_CLOSE(vp, ap->a_mode, ap->a_cred, ap->a_p); 189 return (error); 190 } 191 192 /* 193 * Vnode op for read 194 */ 195 /* ARGSUSED */ 196 fifo_read(ap) 197 struct vop_read_args /* { 198 struct vnode *a_vp; 199 struct uio *a_uio; 200 int a_ioflag; 201 struct ucred *a_cred; 202 } */ *ap; 203 { 204 register struct uio *uio = ap->a_uio; 205 register struct socket *rso = ap->a_vp->v_fifoinfo->fi_readsock; 206 int error, startresid; 207 208 #ifdef DIAGNOSTIC 209 if (uio->uio_rw != UIO_READ) 210 panic("fifo_read mode"); 211 #endif 212 if (uio->uio_resid == 0) 213 return (0); 214 if (ap->a_ioflag & IO_NDELAY) 215 rso->so_state |= SS_NBIO; 216 startresid = uio->uio_resid; 217 VOP_UNLOCK(ap->a_vp); 218 error = soreceive(rso, (struct mbuf **)0, uio, (struct mbuf **)0, 219 (struct mbuf **)0, (int *)0); 220 VOP_LOCK(ap->a_vp); 221 /* 222 * Clear EOF indication after first such return. 223 */ 224 if (uio->uio_resid == startresid) 225 rso->so_state &= ~SS_CANTRCVMORE; 226 if (ap->a_ioflag & IO_NDELAY) 227 rso->so_state &= ~SS_NBIO; 228 return (error); 229 } 230 231 /* 232 * Vnode op for write 233 */ 234 /* ARGSUSED */ 235 fifo_write(ap) 236 struct vop_write_args /* { 237 struct vnode *a_vp; 238 struct uio *a_uio; 239 int a_ioflag; 240 struct ucred *a_cred; 241 } */ *ap; 242 { 243 struct socket *wso = ap->a_vp->v_fifoinfo->fi_writesock; 244 int error; 245 246 #ifdef DIAGNOSTIC 247 if (ap->a_uio->uio_rw != UIO_WRITE) 248 panic("fifo_write mode"); 249 #endif 250 if (ap->a_ioflag & IO_NDELAY) 251 wso->so_state |= SS_NBIO; 252 VOP_UNLOCK(ap->a_vp); 253 error = sosend(wso, (struct mbuf *)0, ap->a_uio, 0, (struct mbuf *)0, 0); 254 VOP_LOCK(ap->a_vp); 255 if (ap->a_ioflag & IO_NDELAY) 256 wso->so_state &= ~SS_NBIO; 257 return (error); 258 } 259 260 /* 261 * Device ioctl operation. 262 */ 263 /* ARGSUSED */ 264 fifo_ioctl(ap) 265 struct vop_ioctl_args /* { 266 struct vnode *a_vp; 267 int a_command; 268 caddr_t a_data; 269 int a_fflag; 270 struct ucred *a_cred; 271 struct proc *a_p; 272 } */ *ap; 273 { 274 struct file filetmp; 275 276 if (ap->a_command == FIONBIO) 277 return (0); 278 if (ap->a_fflag & FREAD) 279 filetmp.f_data = (caddr_t)ap->a_vp->v_fifoinfo->fi_readsock; 280 else 281 filetmp.f_data = (caddr_t)ap->a_vp->v_fifoinfo->fi_writesock; 282 return (soo_ioctl(&filetmp, ap->a_command, ap->a_data, ap->a_p)); 283 } 284 285 /* ARGSUSED */ 286 fifo_select(ap) 287 struct vop_select_args /* { 288 struct vnode *a_vp; 289 int a_which; 290 int a_fflags; 291 struct ucred *a_cred; 292 struct proc *a_p; 293 } */ *ap; 294 { 295 struct file filetmp; 296 297 if (ap->a_fflags & FREAD) 298 filetmp.f_data = (caddr_t)ap->a_vp->v_fifoinfo->fi_readsock; 299 else 300 filetmp.f_data = (caddr_t)ap->a_vp->v_fifoinfo->fi_writesock; 301 return (soo_select(&filetmp, ap->a_which, ap->a_p)); 302 } 303 304 /* 305 * This is a noop, simply returning what one has been given. 306 */ 307 fifo_bmap(ap) 308 struct vop_bmap_args /* { 309 struct vnode *a_vp; 310 daddr_t a_bn; 311 struct vnode **a_vpp; 312 daddr_t *a_bnp; 313 int *a_runp; 314 } */ *ap; 315 { 316 317 if (ap->a_vpp != NULL) 318 *ap->a_vpp = ap->a_vp; 319 if (ap->a_bnp != NULL) 320 *ap->a_bnp = ap->a_bn; 321 if (ap->a_runp != NULL) 322 *ap->a_runp = 0; 323 return (0); 324 } 325 326 /* 327 * At the moment we do not do any locking. 328 */ 329 /* ARGSUSED */ 330 fifo_lock(ap) 331 struct vop_lock_args /* { 332 struct vnode *a_vp; 333 } */ *ap; 334 { 335 336 return (0); 337 } 338 339 /* ARGSUSED */ 340 fifo_unlock(ap) 341 struct vop_unlock_args /* { 342 struct vnode *a_vp; 343 } */ *ap; 344 { 345 346 return (0); 347 } 348 349 /* 350 * Device close routine 351 */ 352 /* ARGSUSED */ 353 fifo_close(ap) 354 struct vop_close_args /* { 355 struct vnode *a_vp; 356 int a_fflag; 357 struct ucred *a_cred; 358 struct proc *a_p; 359 } */ *ap; 360 { 361 register struct vnode *vp = ap->a_vp; 362 register struct fifoinfo *fip = vp->v_fifoinfo; 363 int error1, error2; 364 365 if (ap->a_fflag & FWRITE) { 366 fip->fi_writers--; 367 if (fip->fi_writers == 0) 368 socantrcvmore(fip->fi_readsock); 369 } else { 370 fip->fi_readers--; 371 if (fip->fi_readers == 0) 372 socantsendmore(fip->fi_writesock); 373 } 374 if (vp->v_usecount > 1) 375 return (0); 376 error1 = soclose(fip->fi_readsock); 377 error2 = soclose(fip->fi_writesock); 378 FREE(fip, M_VNODE); 379 vp->v_fifoinfo = NULL; 380 if (error1) 381 return (error1); 382 return (error2); 383 } 384 385 /* 386 * Print out the contents of a fifo vnode. 387 */ 388 fifo_print(ap) 389 struct vop_print_args /* { 390 struct vnode *a_vp; 391 } */ *ap; 392 { 393 394 printf("tag VT_NON"); 395 fifo_printinfo(ap->a_vp); 396 printf("\n"); 397 } 398 399 /* 400 * Print out internal contents of a fifo vnode. 401 */ 402 fifo_printinfo(vp) 403 struct vnode *vp; 404 { 405 register struct fifoinfo *fip = vp->v_fifoinfo; 406 407 printf(", fifo with %d readers and %d writers", 408 fip->fi_readers, fip->fi_writers); 409 } 410 411 /* 412 * Return POSIX pathconf information applicable to fifo's. 413 */ 414 fifo_pathconf(ap) 415 struct vop_pathconf_args /* { 416 struct vnode *a_vp; 417 int a_name; 418 int *a_retval; 419 } */ *ap; 420 { 421 422 switch (ap->a_name) { 423 case _PC_LINK_MAX: 424 *ap->a_retval = LINK_MAX; 425 return (0); 426 case _PC_PIPE_BUF: 427 *ap->a_retval = PIPE_BUF; 428 return (0); 429 case _PC_CHOWN_RESTRICTED: 430 *ap->a_retval = 1; 431 return (0); 432 default: 433 return (EINVAL); 434 } 435 /* NOTREACHED */ 436 } 437 438 /* 439 * Fifo failed operation 440 */ 441 fifo_ebadf() 442 { 443 444 return (EBADF); 445 } 446 447 /* 448 * Fifo advisory byte-level locks. 449 */ 450 /* ARGSUSED */ 451 fifo_advlock(ap) 452 struct vop_advlock_args /* { 453 struct vnode *a_vp; 454 caddr_t a_id; 455 int a_op; 456 struct flock *a_fl; 457 int a_flags; 458 } */ *ap; 459 { 460 461 return (EOPNOTSUPP); 462 } 463 464 /* 465 * Fifo bad operation 466 */ 467 fifo_badop() 468 { 469 470 panic("fifo_badop called"); 471 /* NOTREACHED */ 472 } 473