1 /* 2 * Copyright (c) 1990, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * %sccs.include.redist.c% 6 * 7 * @(#)fifo_vnops.c 8.2 (Berkeley) 01/04/94 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_ioctl_desc, fifo_ioctl }, /* ioctl */ 50 { &vop_select_desc, fifo_select }, /* select */ 51 { &vop_mmap_desc, fifo_mmap }, /* mmap */ 52 { &vop_fsync_desc, fifo_fsync }, /* fsync */ 53 { &vop_seek_desc, fifo_seek }, /* seek */ 54 { &vop_remove_desc, fifo_remove }, /* remove */ 55 { &vop_link_desc, fifo_link }, /* link */ 56 { &vop_rename_desc, fifo_rename }, /* rename */ 57 { &vop_mkdir_desc, fifo_mkdir }, /* mkdir */ 58 { &vop_rmdir_desc, fifo_rmdir }, /* rmdir */ 59 { &vop_symlink_desc, fifo_symlink }, /* symlink */ 60 { &vop_readdir_desc, fifo_readdir }, /* readdir */ 61 { &vop_readlink_desc, fifo_readlink }, /* readlink */ 62 { &vop_abortop_desc, fifo_abortop }, /* abortop */ 63 { &vop_inactive_desc, fifo_inactive }, /* inactive */ 64 { &vop_reclaim_desc, fifo_reclaim }, /* reclaim */ 65 { &vop_lock_desc, fifo_lock }, /* lock */ 66 { &vop_unlock_desc, fifo_unlock }, /* unlock */ 67 { &vop_bmap_desc, fifo_bmap }, /* bmap */ 68 { &vop_strategy_desc, fifo_strategy }, /* strategy */ 69 { &vop_print_desc, fifo_print }, /* print */ 70 { &vop_islocked_desc, fifo_islocked }, /* islocked */ 71 { &vop_pathconf_desc, fifo_pathconf }, /* pathconf */ 72 { &vop_advlock_desc, fifo_advlock }, /* advlock */ 73 { &vop_blkatoff_desc, fifo_blkatoff }, /* blkatoff */ 74 { &vop_valloc_desc, fifo_valloc }, /* valloc */ 75 { &vop_vfree_desc, fifo_vfree }, /* vfree */ 76 { &vop_truncate_desc, fifo_truncate }, /* truncate */ 77 { &vop_update_desc, fifo_update }, /* update */ 78 { &vop_bwrite_desc, fifo_bwrite }, /* bwrite */ 79 { (struct vnodeop_desc*)NULL, (int(*)())NULL } 80 }; 81 struct vnodeopv_desc fifo_vnodeop_opv_desc = 82 { &fifo_vnodeop_p, fifo_vnodeop_entries }; 83 84 /* 85 * Trivial lookup routine that always fails. 86 */ 87 /* ARGSUSED */ 88 fifo_lookup(ap) 89 struct vop_lookup_args /* { 90 struct vnode * a_dvp; 91 struct vnode ** a_vpp; 92 struct componentname * a_cnp; 93 } */ *ap; 94 { 95 96 *ap->a_vpp = NULL; 97 return (ENOTDIR); 98 } 99 100 /* 101 * Open called to set up a new instance of a fifo or 102 * to find an active instance of a fifo. 103 */ 104 /* ARGSUSED */ 105 fifo_open(ap) 106 struct vop_open_args /* { 107 struct vnode *a_vp; 108 int a_mode; 109 struct ucred *a_cred; 110 struct proc *a_p; 111 } */ *ap; 112 { 113 register struct vnode *vp = ap->a_vp; 114 register struct fifoinfo *fip; 115 struct socket *rso, *wso; 116 int error; 117 static char openstr[] = "fifo"; 118 119 if ((ap->a_mode & (FREAD|FWRITE)) == (FREAD|FWRITE)) 120 return (EINVAL); 121 if ((fip = vp->v_fifoinfo) == NULL) { 122 MALLOC(fip, struct fifoinfo *, sizeof(*fip), M_VNODE, M_WAITOK); 123 vp->v_fifoinfo = fip; 124 if (error = socreate(AF_UNIX, &rso, SOCK_STREAM, 0)) { 125 free(fip, M_VNODE); 126 vp->v_fifoinfo = NULL; 127 return (error); 128 } 129 fip->fi_readsock = rso; 130 if (error = socreate(AF_UNIX, &wso, SOCK_STREAM, 0)) { 131 (void)soclose(rso); 132 free(fip, M_VNODE); 133 vp->v_fifoinfo = NULL; 134 return (error); 135 } 136 fip->fi_writesock = wso; 137 if (error = unp_connect2(wso, rso)) { 138 (void)soclose(wso); 139 (void)soclose(rso); 140 free(fip, M_VNODE); 141 vp->v_fifoinfo = NULL; 142 return (error); 143 } 144 fip->fi_readers = fip->fi_writers = 0; 145 wso->so_state |= SS_CANTRCVMORE; 146 rso->so_state |= SS_CANTSENDMORE; 147 } 148 error = 0; 149 if (ap->a_mode & FREAD) { 150 fip->fi_readers++; 151 if (fip->fi_readers == 1) { 152 fip->fi_writesock->so_state &= ~SS_CANTSENDMORE; 153 if (fip->fi_writers > 0) 154 wakeup((caddr_t)&fip->fi_writers); 155 } 156 if (ap->a_mode & O_NONBLOCK) 157 return (0); 158 while (fip->fi_writers == 0) { 159 VOP_UNLOCK(vp); 160 error = tsleep((caddr_t)&fip->fi_readers, 161 PCATCH | PSOCK, openstr, 0); 162 VOP_LOCK(vp); 163 if (error) 164 break; 165 } 166 } else { 167 fip->fi_writers++; 168 if (fip->fi_readers == 0 && (ap->a_mode & O_NONBLOCK)) { 169 error = ENXIO; 170 } else { 171 if (fip->fi_writers == 1) { 172 fip->fi_readsock->so_state &= ~SS_CANTRCVMORE; 173 if (fip->fi_readers > 0) 174 wakeup((caddr_t)&fip->fi_readers); 175 } 176 while (fip->fi_readers == 0) { 177 VOP_UNLOCK(vp); 178 error = tsleep((caddr_t)&fip->fi_writers, 179 PCATCH | PSOCK, openstr, 0); 180 VOP_LOCK(vp); 181 if (error) 182 break; 183 } 184 } 185 } 186 if (error) 187 VOP_CLOSE(vp, ap->a_mode, ap->a_cred, ap->a_p); 188 return (error); 189 } 190 191 /* 192 * Vnode op for read 193 */ 194 /* ARGSUSED */ 195 fifo_read(ap) 196 struct vop_read_args /* { 197 struct vnode *a_vp; 198 struct uio *a_uio; 199 int a_ioflag; 200 struct ucred *a_cred; 201 } */ *ap; 202 { 203 register struct uio *uio = ap->a_uio; 204 register struct socket *rso = ap->a_vp->v_fifoinfo->fi_readsock; 205 int error, startresid; 206 207 #ifdef DIAGNOSTIC 208 if (uio->uio_rw != UIO_READ) 209 panic("fifo_read mode"); 210 #endif 211 if (uio->uio_resid == 0) 212 return (0); 213 if (ap->a_ioflag & IO_NDELAY) 214 rso->so_state |= SS_NBIO; 215 startresid = uio->uio_resid; 216 VOP_UNLOCK(ap->a_vp); 217 error = soreceive(rso, (struct mbuf **)0, uio, (int *)0, 218 (struct mbuf **)0, (struct mbuf **)0); 219 VOP_LOCK(ap->a_vp); 220 /* 221 * Clear EOF indication after first such return. 222 */ 223 if (uio->uio_resid == startresid) 224 rso->so_state &= ~SS_CANTRCVMORE; 225 if (ap->a_ioflag & IO_NDELAY) 226 rso->so_state &= ~SS_NBIO; 227 return (error); 228 } 229 230 /* 231 * Vnode op for write 232 */ 233 /* ARGSUSED */ 234 fifo_write(ap) 235 struct vop_write_args /* { 236 struct vnode *a_vp; 237 struct uio *a_uio; 238 int a_ioflag; 239 struct ucred *a_cred; 240 } */ *ap; 241 { 242 struct socket *wso = ap->a_vp->v_fifoinfo->fi_writesock; 243 int error; 244 245 #ifdef DIAGNOSTIC 246 if (ap->a_uio->uio_rw != UIO_WRITE) 247 panic("fifo_write mode"); 248 #endif 249 if (ap->a_ioflag & IO_NDELAY) 250 wso->so_state |= SS_NBIO; 251 VOP_UNLOCK(ap->a_vp); 252 error = sosend(wso, (struct mbuf *)0, ap->a_uio, 0, (struct mbuf *)0, 0); 253 VOP_LOCK(ap->a_vp); 254 if (ap->a_ioflag & IO_NDELAY) 255 wso->so_state &= ~SS_NBIO; 256 return (error); 257 } 258 259 /* 260 * Device ioctl operation. 261 */ 262 /* ARGSUSED */ 263 fifo_ioctl(ap) 264 struct vop_ioctl_args /* { 265 struct vnode *a_vp; 266 int a_command; 267 caddr_t a_data; 268 int a_fflag; 269 struct ucred *a_cred; 270 struct proc *a_p; 271 } */ *ap; 272 { 273 struct file filetmp; 274 275 if (ap->a_command == FIONBIO) 276 return (0); 277 if (ap->a_fflag & FREAD) 278 filetmp.f_data = (caddr_t)ap->a_vp->v_fifoinfo->fi_readsock; 279 else 280 filetmp.f_data = (caddr_t)ap->a_vp->v_fifoinfo->fi_writesock; 281 return (soo_ioctl(&filetmp, ap->a_command, ap->a_data, ap->a_p)); 282 } 283 284 /* ARGSUSED */ 285 fifo_select(ap) 286 struct vop_select_args /* { 287 struct vnode *a_vp; 288 int a_which; 289 int a_fflags; 290 struct ucred *a_cred; 291 struct proc *a_p; 292 } */ *ap; 293 { 294 struct file filetmp; 295 296 if (ap->a_fflags & FREAD) 297 filetmp.f_data = (caddr_t)ap->a_vp->v_fifoinfo->fi_readsock; 298 else 299 filetmp.f_data = (caddr_t)ap->a_vp->v_fifoinfo->fi_writesock; 300 return (soo_select(&filetmp, ap->a_which, ap->a_p)); 301 } 302 303 /* 304 * This is a noop, simply returning what one has been given. 305 */ 306 fifo_bmap(ap) 307 struct vop_bmap_args /* { 308 struct vnode *a_vp; 309 daddr_t a_bn; 310 struct vnode **a_vpp; 311 daddr_t *a_bnp; 312 } */ *ap; 313 { 314 315 if (ap->a_vpp != NULL) 316 *ap->a_vpp = ap->a_vp; 317 if (ap->a_bnp != NULL) 318 *ap->a_bnp = ap->a_bn; 319 return (0); 320 } 321 322 /* 323 * At the moment we do not do any locking. 324 */ 325 /* ARGSUSED */ 326 fifo_lock(ap) 327 struct vop_lock_args /* { 328 struct vnode *a_vp; 329 } */ *ap; 330 { 331 332 return (0); 333 } 334 335 /* ARGSUSED */ 336 fifo_unlock(ap) 337 struct vop_unlock_args /* { 338 struct vnode *a_vp; 339 } */ *ap; 340 { 341 342 return (0); 343 } 344 345 /* 346 * Device close routine 347 */ 348 /* ARGSUSED */ 349 fifo_close(ap) 350 struct vop_close_args /* { 351 struct vnode *a_vp; 352 int a_fflag; 353 struct ucred *a_cred; 354 struct proc *a_p; 355 } */ *ap; 356 { 357 register struct vnode *vp = ap->a_vp; 358 register struct fifoinfo *fip = vp->v_fifoinfo; 359 int error1, error2; 360 361 if (ap->a_fflag & FWRITE) { 362 fip->fi_writers--; 363 if (fip->fi_writers == 0) 364 socantrcvmore(fip->fi_readsock); 365 } else { 366 fip->fi_readers--; 367 if (fip->fi_readers == 0) 368 socantsendmore(fip->fi_writesock); 369 } 370 if (vp->v_usecount > 1) 371 return (0); 372 error1 = soclose(fip->fi_readsock); 373 error2 = soclose(fip->fi_writesock); 374 FREE(fip, M_VNODE); 375 vp->v_fifoinfo = NULL; 376 if (error1) 377 return (error1); 378 return (error2); 379 } 380 381 /* 382 * Print out the contents of a fifo vnode. 383 */ 384 fifo_print(ap) 385 struct vop_print_args /* { 386 struct vnode *a_vp; 387 } */ *ap; 388 { 389 390 printf("tag VT_NON"); 391 fifo_printinfo(ap->a_vp); 392 printf("\n"); 393 } 394 395 /* 396 * Print out internal contents of a fifo vnode. 397 */ 398 fifo_printinfo(vp) 399 struct vnode *vp; 400 { 401 register struct fifoinfo *fip = vp->v_fifoinfo; 402 403 printf(", fifo with %d readers and %d writers", 404 fip->fi_readers, fip->fi_writers); 405 } 406 407 /* 408 * Return POSIX pathconf information applicable to fifo's. 409 */ 410 fifo_pathconf(ap) 411 struct vop_pathconf_args /* { 412 struct vnode *a_vp; 413 int a_name; 414 int *a_retval; 415 } */ *ap; 416 { 417 418 switch (ap->a_name) { 419 case _PC_LINK_MAX: 420 *ap->a_retval = LINK_MAX; 421 return (0); 422 case _PC_PIPE_BUF: 423 *ap->a_retval = PIPE_BUF; 424 return (0); 425 case _PC_CHOWN_RESTRICTED: 426 *ap->a_retval = 1; 427 return (0); 428 default: 429 return (EINVAL); 430 } 431 /* NOTREACHED */ 432 } 433 434 /* 435 * Fifo failed operation 436 */ 437 fifo_ebadf() 438 { 439 440 return (EBADF); 441 } 442 443 /* 444 * Fifo advisory byte-level locks. 445 */ 446 /* ARGSUSED */ 447 fifo_advlock(ap) 448 struct vop_advlock_args /* { 449 struct vnode *a_vp; 450 caddr_t a_id; 451 int a_op; 452 struct flock *a_fl; 453 int a_flags; 454 } */ *ap; 455 { 456 457 return (EOPNOTSUPP); 458 } 459 460 /* 461 * Fifo bad operation 462 */ 463 fifo_badop() 464 { 465 466 panic("fifo_badop called"); 467 /* NOTREACHED */ 468 } 469