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 8.7 (Berkeley) 02/22/95 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_revoke_desc, fifo_revoke }, /* revoke */ 53 { &vop_mmap_desc, fifo_mmap }, /* mmap */ 54 { &vop_fsync_desc, fifo_fsync }, /* fsync */ 55 { &vop_seek_desc, fifo_seek }, /* seek */ 56 { &vop_remove_desc, fifo_remove }, /* remove */ 57 { &vop_link_desc, fifo_link }, /* link */ 58 { &vop_rename_desc, fifo_rename }, /* rename */ 59 { &vop_mkdir_desc, fifo_mkdir }, /* mkdir */ 60 { &vop_rmdir_desc, fifo_rmdir }, /* rmdir */ 61 { &vop_symlink_desc, fifo_symlink }, /* symlink */ 62 { &vop_readdir_desc, fifo_readdir }, /* readdir */ 63 { &vop_readlink_desc, fifo_readlink }, /* readlink */ 64 { &vop_abortop_desc, fifo_abortop }, /* abortop */ 65 { &vop_inactive_desc, fifo_inactive }, /* inactive */ 66 { &vop_reclaim_desc, fifo_reclaim }, /* reclaim */ 67 { &vop_lock_desc, fifo_lock }, /* lock */ 68 { &vop_unlock_desc, fifo_unlock }, /* unlock */ 69 { &vop_bmap_desc, fifo_bmap }, /* bmap */ 70 { &vop_strategy_desc, fifo_strategy }, /* strategy */ 71 { &vop_print_desc, fifo_print }, /* print */ 72 { &vop_islocked_desc, fifo_islocked }, /* islocked */ 73 { &vop_pathconf_desc, fifo_pathconf }, /* pathconf */ 74 { &vop_advlock_desc, fifo_advlock }, /* advlock */ 75 { &vop_blkatoff_desc, fifo_blkatoff }, /* blkatoff */ 76 { &vop_valloc_desc, fifo_valloc }, /* valloc */ 77 { &vop_vfree_desc, fifo_vfree }, /* vfree */ 78 { &vop_truncate_desc, fifo_truncate }, /* truncate */ 79 { &vop_update_desc, fifo_update }, /* update */ 80 { &vop_bwrite_desc, fifo_bwrite }, /* bwrite */ 81 { (struct vnodeop_desc*)NULL, (int(*)())NULL } 82 }; 83 struct vnodeopv_desc fifo_vnodeop_opv_desc = 84 { &fifo_vnodeop_p, fifo_vnodeop_entries }; 85 86 /* 87 * Trivial lookup routine that always fails. 88 */ 89 /* ARGSUSED */ 90 fifo_lookup(ap) 91 struct vop_lookup_args /* { 92 struct vnode * a_dvp; 93 struct vnode ** a_vpp; 94 struct componentname * a_cnp; 95 } */ *ap; 96 { 97 98 *ap->a_vpp = NULL; 99 return (ENOTDIR); 100 } 101 102 /* 103 * Open called to set up a new instance of a fifo or 104 * to find an active instance of a fifo. 105 */ 106 /* ARGSUSED */ 107 fifo_open(ap) 108 struct vop_open_args /* { 109 struct vnode *a_vp; 110 int a_mode; 111 struct ucred *a_cred; 112 struct proc *a_p; 113 } */ *ap; 114 { 115 register struct vnode *vp = ap->a_vp; 116 register struct fifoinfo *fip; 117 struct socket *rso, *wso; 118 int error; 119 static char openstr[] = "fifo"; 120 121 if ((ap->a_mode & (FREAD|FWRITE)) == (FREAD|FWRITE)) 122 return (EINVAL); 123 if ((fip = vp->v_fifoinfo) == NULL) { 124 MALLOC(fip, struct fifoinfo *, sizeof(*fip), M_VNODE, M_WAITOK); 125 vp->v_fifoinfo = fip; 126 if (error = socreate(AF_LOCAL, &rso, SOCK_STREAM, 0)) { 127 free(fip, M_VNODE); 128 vp->v_fifoinfo = NULL; 129 return (error); 130 } 131 fip->fi_readsock = rso; 132 if (error = socreate(AF_LOCAL, &wso, SOCK_STREAM, 0)) { 133 (void)soclose(rso); 134 free(fip, M_VNODE); 135 vp->v_fifoinfo = NULL; 136 return (error); 137 } 138 fip->fi_writesock = wso; 139 if (error = unp_connect2(wso, rso)) { 140 (void)soclose(wso); 141 (void)soclose(rso); 142 free(fip, M_VNODE); 143 vp->v_fifoinfo = NULL; 144 return (error); 145 } 146 fip->fi_readers = fip->fi_writers = 0; 147 wso->so_state |= SS_CANTRCVMORE; 148 rso->so_state |= SS_CANTSENDMORE; 149 } 150 error = 0; 151 if (ap->a_mode & FREAD) { 152 fip->fi_readers++; 153 if (fip->fi_readers == 1) { 154 fip->fi_writesock->so_state &= ~SS_CANTSENDMORE; 155 if (fip->fi_writers > 0) 156 wakeup((caddr_t)&fip->fi_writers); 157 } 158 if (ap->a_mode & O_NONBLOCK) 159 return (0); 160 while (fip->fi_writers == 0) { 161 VOP_UNLOCK(vp); 162 error = tsleep((caddr_t)&fip->fi_readers, 163 PCATCH | PSOCK, openstr, 0); 164 VOP_LOCK(vp); 165 if (error) 166 break; 167 } 168 } else { 169 fip->fi_writers++; 170 if (fip->fi_readers == 0 && (ap->a_mode & O_NONBLOCK)) { 171 error = ENXIO; 172 } else { 173 if (fip->fi_writers == 1) { 174 fip->fi_readsock->so_state &= ~SS_CANTRCVMORE; 175 if (fip->fi_readers > 0) 176 wakeup((caddr_t)&fip->fi_readers); 177 } 178 while (fip->fi_readers == 0) { 179 VOP_UNLOCK(vp); 180 error = tsleep((caddr_t)&fip->fi_writers, 181 PCATCH | PSOCK, openstr, 0); 182 VOP_LOCK(vp); 183 if (error) 184 break; 185 } 186 } 187 } 188 if (error) 189 VOP_CLOSE(vp, ap->a_mode, ap->a_cred, ap->a_p); 190 return (error); 191 } 192 193 /* 194 * Vnode op for read 195 */ 196 /* ARGSUSED */ 197 fifo_read(ap) 198 struct vop_read_args /* { 199 struct vnode *a_vp; 200 struct uio *a_uio; 201 int a_ioflag; 202 struct ucred *a_cred; 203 } */ *ap; 204 { 205 register struct uio *uio = ap->a_uio; 206 register struct socket *rso = ap->a_vp->v_fifoinfo->fi_readsock; 207 int error, startresid; 208 209 #ifdef DIAGNOSTIC 210 if (uio->uio_rw != UIO_READ) 211 panic("fifo_read mode"); 212 #endif 213 if (uio->uio_resid == 0) 214 return (0); 215 if (ap->a_ioflag & IO_NDELAY) 216 rso->so_state |= SS_NBIO; 217 startresid = uio->uio_resid; 218 VOP_UNLOCK(ap->a_vp); 219 error = soreceive(rso, (struct mbuf **)0, uio, (struct mbuf **)0, 220 (struct mbuf **)0, (int *)0); 221 VOP_LOCK(ap->a_vp); 222 /* 223 * Clear EOF indication after first such return. 224 */ 225 if (uio->uio_resid == startresid) 226 rso->so_state &= ~SS_CANTRCVMORE; 227 if (ap->a_ioflag & IO_NDELAY) 228 rso->so_state &= ~SS_NBIO; 229 return (error); 230 } 231 232 /* 233 * Vnode op for write 234 */ 235 /* ARGSUSED */ 236 fifo_write(ap) 237 struct vop_write_args /* { 238 struct vnode *a_vp; 239 struct uio *a_uio; 240 int a_ioflag; 241 struct ucred *a_cred; 242 } */ *ap; 243 { 244 struct socket *wso = ap->a_vp->v_fifoinfo->fi_writesock; 245 int error; 246 247 #ifdef DIAGNOSTIC 248 if (ap->a_uio->uio_rw != UIO_WRITE) 249 panic("fifo_write mode"); 250 #endif 251 if (ap->a_ioflag & IO_NDELAY) 252 wso->so_state |= SS_NBIO; 253 VOP_UNLOCK(ap->a_vp); 254 error = sosend(wso, (struct mbuf *)0, ap->a_uio, 0, (struct mbuf *)0, 0); 255 VOP_LOCK(ap->a_vp); 256 if (ap->a_ioflag & IO_NDELAY) 257 wso->so_state &= ~SS_NBIO; 258 return (error); 259 } 260 261 /* 262 * Device ioctl operation. 263 */ 264 /* ARGSUSED */ 265 fifo_ioctl(ap) 266 struct vop_ioctl_args /* { 267 struct vnode *a_vp; 268 int a_command; 269 caddr_t a_data; 270 int a_fflag; 271 struct ucred *a_cred; 272 struct proc *a_p; 273 } */ *ap; 274 { 275 struct file filetmp; 276 277 if (ap->a_command == FIONBIO) 278 return (0); 279 if (ap->a_fflag & FREAD) 280 filetmp.f_data = (caddr_t)ap->a_vp->v_fifoinfo->fi_readsock; 281 else 282 filetmp.f_data = (caddr_t)ap->a_vp->v_fifoinfo->fi_writesock; 283 return (soo_ioctl(&filetmp, ap->a_command, ap->a_data, ap->a_p)); 284 } 285 286 /* ARGSUSED */ 287 fifo_select(ap) 288 struct vop_select_args /* { 289 struct vnode *a_vp; 290 int a_which; 291 int a_fflags; 292 struct ucred *a_cred; 293 struct proc *a_p; 294 } */ *ap; 295 { 296 struct file filetmp; 297 298 if (ap->a_fflags & FREAD) 299 filetmp.f_data = (caddr_t)ap->a_vp->v_fifoinfo->fi_readsock; 300 else 301 filetmp.f_data = (caddr_t)ap->a_vp->v_fifoinfo->fi_writesock; 302 return (soo_select(&filetmp, ap->a_which, ap->a_p)); 303 } 304 305 /* 306 * This is a noop, simply returning what one has been given. 307 */ 308 fifo_bmap(ap) 309 struct vop_bmap_args /* { 310 struct vnode *a_vp; 311 daddr_t a_bn; 312 struct vnode **a_vpp; 313 daddr_t *a_bnp; 314 int *a_runp; 315 } */ *ap; 316 { 317 318 if (ap->a_vpp != NULL) 319 *ap->a_vpp = ap->a_vp; 320 if (ap->a_bnp != NULL) 321 *ap->a_bnp = ap->a_bn; 322 if (ap->a_runp != NULL) 323 *ap->a_runp = 0; 324 return (0); 325 } 326 327 /* 328 * At the moment we do not do any locking. 329 */ 330 /* ARGSUSED */ 331 fifo_lock(ap) 332 struct vop_lock_args /* { 333 struct vnode *a_vp; 334 } */ *ap; 335 { 336 337 return (0); 338 } 339 340 /* ARGSUSED */ 341 fifo_unlock(ap) 342 struct vop_unlock_args /* { 343 struct vnode *a_vp; 344 } */ *ap; 345 { 346 347 return (0); 348 } 349 350 /* 351 * Device close routine 352 */ 353 /* ARGSUSED */ 354 fifo_close(ap) 355 struct vop_close_args /* { 356 struct vnode *a_vp; 357 int a_fflag; 358 struct ucred *a_cred; 359 struct proc *a_p; 360 } */ *ap; 361 { 362 register struct vnode *vp = ap->a_vp; 363 register struct fifoinfo *fip = vp->v_fifoinfo; 364 int error1, error2; 365 366 if (ap->a_fflag & FWRITE) { 367 fip->fi_writers--; 368 if (fip->fi_writers == 0) 369 socantrcvmore(fip->fi_readsock); 370 } else { 371 fip->fi_readers--; 372 if (fip->fi_readers == 0) 373 socantsendmore(fip->fi_writesock); 374 } 375 if (vp->v_usecount > 1) 376 return (0); 377 error1 = soclose(fip->fi_readsock); 378 error2 = soclose(fip->fi_writesock); 379 FREE(fip, M_VNODE); 380 vp->v_fifoinfo = NULL; 381 if (error1) 382 return (error1); 383 return (error2); 384 } 385 386 /* 387 * Print out the contents of a fifo vnode. 388 */ 389 fifo_print(ap) 390 struct vop_print_args /* { 391 struct vnode *a_vp; 392 } */ *ap; 393 { 394 395 printf("tag VT_NON"); 396 fifo_printinfo(ap->a_vp); 397 printf("\n"); 398 } 399 400 /* 401 * Print out internal contents of a fifo vnode. 402 */ 403 fifo_printinfo(vp) 404 struct vnode *vp; 405 { 406 register struct fifoinfo *fip = vp->v_fifoinfo; 407 408 printf(", fifo with %d readers and %d writers", 409 fip->fi_readers, fip->fi_writers); 410 } 411 412 /* 413 * Return POSIX pathconf information applicable to fifo's. 414 */ 415 fifo_pathconf(ap) 416 struct vop_pathconf_args /* { 417 struct vnode *a_vp; 418 int a_name; 419 int *a_retval; 420 } */ *ap; 421 { 422 423 switch (ap->a_name) { 424 case _PC_LINK_MAX: 425 *ap->a_retval = LINK_MAX; 426 return (0); 427 case _PC_PIPE_BUF: 428 *ap->a_retval = PIPE_BUF; 429 return (0); 430 case _PC_CHOWN_RESTRICTED: 431 *ap->a_retval = 1; 432 return (0); 433 default: 434 return (EINVAL); 435 } 436 /* NOTREACHED */ 437 } 438 439 /* 440 * Fifo failed operation 441 */ 442 fifo_ebadf() 443 { 444 445 return (EBADF); 446 } 447 448 /* 449 * Fifo advisory byte-level locks. 450 */ 451 /* ARGSUSED */ 452 fifo_advlock(ap) 453 struct vop_advlock_args /* { 454 struct vnode *a_vp; 455 caddr_t a_id; 456 int a_op; 457 struct flock *a_fl; 458 int a_flags; 459 } */ *ap; 460 { 461 462 return (EOPNOTSUPP); 463 } 464 465 /* 466 * Fifo bad operation 467 */ 468 fifo_badop() 469 { 470 471 panic("fifo_badop called"); 472 /* NOTREACHED */ 473 } 474