1 /* 2 * Copyright (c) 1990 The Regents of the University of California. 3 * All rights reserved. 4 * 5 * %sccs.include.redist.c% 6 * 7 * @(#)fifo_vnops.c 7.17 (Berkeley) 07/12/92 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_advlock_desc, fifo_advlock }, /* advlock */ 72 { &vop_blkatoff_desc, fifo_blkatoff }, /* blkatoff */ 73 { &vop_valloc_desc, fifo_valloc }, /* valloc */ 74 { &vop_vfree_desc, fifo_vfree }, /* vfree */ 75 { &vop_truncate_desc, fifo_truncate }, /* truncate */ 76 { &vop_update_desc, fifo_update }, /* update */ 77 { &vop_bwrite_desc, fifo_bwrite }, /* bwrite */ 78 { (struct vnodeop_desc*)NULL, (int(*)())NULL } 79 }; 80 struct vnodeopv_desc fifo_vnodeop_opv_desc = 81 { &fifo_vnodeop_p, fifo_vnodeop_entries }; 82 83 /* 84 * Trivial lookup routine that always fails. 85 */ 86 /* ARGSUSED */ 87 fifo_lookup(ap) 88 struct vop_lookup_args /* { 89 struct vnode * a_dvp; 90 struct vnode ** a_vpp; 91 struct componentname * a_cnp; 92 } */ *ap; 93 { 94 95 *ap->a_vpp = NULL; 96 return (ENOTDIR); 97 } 98 99 /* 100 * Open called to set up a new instance of a fifo or 101 * to find an active instance of a fifo. 102 */ 103 /* ARGSUSED */ 104 fifo_open(ap) 105 struct vop_open_args /* { 106 struct vnode *a_vp; 107 int a_mode; 108 struct ucred *a_cred; 109 struct proc *a_p; 110 } */ *ap; 111 { 112 register struct vnode *vp = ap->a_vp; 113 register struct fifoinfo *fip; 114 struct socket *rso, *wso; 115 int error; 116 static char openstr[] = "fifo"; 117 118 if ((ap->a_mode & (FREAD|FWRITE)) == (FREAD|FWRITE)) 119 return (EINVAL); 120 if ((fip = vp->v_fifoinfo) == NULL) { 121 MALLOC(fip, struct fifoinfo *, sizeof(*fip), M_VNODE, M_WAITOK); 122 vp->v_fifoinfo = fip; 123 if (error = socreate(AF_UNIX, &rso, SOCK_STREAM, 0)) { 124 free(fip, M_VNODE); 125 vp->v_fifoinfo = NULL; 126 return (error); 127 } 128 fip->fi_readsock = rso; 129 if (error = socreate(AF_UNIX, &wso, SOCK_STREAM, 0)) { 130 (void)soclose(rso); 131 free(fip, M_VNODE); 132 vp->v_fifoinfo = NULL; 133 return (error); 134 } 135 fip->fi_writesock = wso; 136 if (error = unp_connect2(wso, rso)) { 137 (void)soclose(wso); 138 (void)soclose(rso); 139 free(fip, M_VNODE); 140 vp->v_fifoinfo = NULL; 141 return (error); 142 } 143 fip->fi_readers = fip->fi_writers = 0; 144 wso->so_state |= SS_CANTRCVMORE; 145 rso->so_state |= SS_CANTSENDMORE; 146 } 147 error = 0; 148 if (ap->a_mode & FREAD) { 149 fip->fi_readers++; 150 if (fip->fi_readers == 1) { 151 fip->fi_writesock->so_state &= ~SS_CANTSENDMORE; 152 if (fip->fi_writers > 0) 153 wakeup((caddr_t)&fip->fi_writers); 154 } 155 if (ap->a_mode & O_NONBLOCK) 156 return (0); 157 while (fip->fi_writers == 0) { 158 VOP_UNLOCK(vp); 159 error = tsleep((caddr_t)&fip->fi_readers, PSOCK, 160 openstr, 0); 161 VOP_LOCK(vp); 162 if (error) 163 break; 164 } 165 } else { 166 fip->fi_writers++; 167 if (fip->fi_readers == 0 && (ap->a_mode & O_NONBLOCK)) { 168 error = ENXIO; 169 } else { 170 if (fip->fi_writers == 1) { 171 fip->fi_readsock->so_state &= ~SS_CANTRCVMORE; 172 if (fip->fi_readers > 0) 173 wakeup((caddr_t)&fip->fi_readers); 174 } 175 while (fip->fi_readers == 0) { 176 VOP_UNLOCK(vp); 177 error = tsleep((caddr_t)&fip->fi_writers, 178 PSOCK, openstr, 0); 179 VOP_LOCK(vp); 180 if (error) 181 break; 182 } 183 } 184 } 185 if (error) 186 VOP_CLOSE(vp, ap->a_mode, ap->a_cred, ap->a_p); 187 return (error); 188 } 189 190 /* 191 * Vnode op for read 192 */ 193 /* ARGSUSED */ 194 fifo_read(ap) 195 struct vop_read_args /* { 196 struct vnode *a_vp; 197 struct uio *a_uio; 198 int a_ioflag; 199 struct ucred *a_cred; 200 } */ *ap; 201 { 202 register struct uio *uio = ap->a_uio; 203 register struct socket *rso = ap->a_vp->v_fifoinfo->fi_readsock; 204 int error, startresid; 205 206 #ifdef DIAGNOSTIC 207 if (uio->uio_rw != UIO_READ) 208 panic("fifo_read mode"); 209 #endif 210 if (uio->uio_resid == 0) 211 return (0); 212 if (ap->a_ioflag & IO_NDELAY) 213 rso->so_state |= SS_NBIO; 214 startresid = uio->uio_resid; 215 VOP_UNLOCK(ap->a_vp); 216 error = soreceive(rso, (struct mbuf **)0, uio, (int *)0, 217 (struct mbuf **)0, (struct mbuf **)0); 218 VOP_LOCK(ap->a_vp); 219 /* 220 * Clear EOF indication after first such return. 221 */ 222 if (uio->uio_resid == startresid) 223 rso->so_state &= ~SS_CANTRCVMORE; 224 if (ap->a_ioflag & IO_NDELAY) 225 rso->so_state &= ~SS_NBIO; 226 return (error); 227 } 228 229 /* 230 * Vnode op for write 231 */ 232 /* ARGSUSED */ 233 fifo_write(ap) 234 struct vop_write_args /* { 235 struct vnode *a_vp; 236 struct uio *a_uio; 237 int a_ioflag; 238 struct ucred *a_cred; 239 } */ *ap; 240 { 241 struct socket *wso = ap->a_vp->v_fifoinfo->fi_writesock; 242 int error; 243 244 #ifdef DIAGNOSTIC 245 if (ap->a_uio->uio_rw != UIO_WRITE) 246 panic("fifo_write mode"); 247 #endif 248 if (ap->a_ioflag & IO_NDELAY) 249 wso->so_state |= SS_NBIO; 250 VOP_UNLOCK(ap->a_vp); 251 error = sosend(wso, (struct mbuf *)0, ap->a_uio, 0, (struct mbuf *)0, 0); 252 VOP_LOCK(ap->a_vp); 253 if (ap->a_ioflag & IO_NDELAY) 254 wso->so_state &= ~SS_NBIO; 255 return (error); 256 } 257 258 /* 259 * Device ioctl operation. 260 */ 261 /* ARGSUSED */ 262 fifo_ioctl(ap) 263 struct vop_ioctl_args /* { 264 struct vnode *a_vp; 265 int a_command; 266 caddr_t a_data; 267 int a_fflag; 268 struct ucred *a_cred; 269 struct proc *a_p; 270 } */ *ap; 271 { 272 struct file filetmp; 273 int error; 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 int error; 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 } */ *ap; 314 { 315 316 if (ap->a_vpp != NULL) 317 *ap->a_vpp = ap->a_vp; 318 if (ap->a_bnp != NULL) 319 *ap->a_bnp = ap->a_bn; 320 return (0); 321 } 322 323 /* 324 * At the moment we do not do any locking. 325 */ 326 /* ARGSUSED */ 327 fifo_lock(ap) 328 struct vop_lock_args /* { 329 struct vnode *a_vp; 330 } */ *ap; 331 { 332 333 return (0); 334 } 335 336 /* ARGSUSED */ 337 fifo_unlock(ap) 338 struct vop_unlock_args /* { 339 struct vnode *a_vp; 340 } */ *ap; 341 { 342 343 return (0); 344 } 345 346 /* 347 * Device close routine 348 */ 349 /* ARGSUSED */ 350 fifo_close(ap) 351 struct vop_close_args /* { 352 struct vnode *a_vp; 353 int a_fflag; 354 struct ucred *a_cred; 355 struct proc *a_p; 356 } */ *ap; 357 { 358 register struct vnode *vp = ap->a_vp; 359 register struct fifoinfo *fip = vp->v_fifoinfo; 360 int error1, error2; 361 362 if (ap->a_fflag & FWRITE) { 363 fip->fi_writers--; 364 if (fip->fi_writers == 0) 365 socantrcvmore(fip->fi_readsock); 366 } else { 367 fip->fi_readers--; 368 if (fip->fi_readers == 0) 369 socantsendmore(fip->fi_writesock); 370 } 371 if (vp->v_usecount > 1) 372 return (0); 373 error1 = soclose(fip->fi_readsock); 374 error2 = soclose(fip->fi_writesock); 375 FREE(fip, M_VNODE); 376 vp->v_fifoinfo = NULL; 377 if (error1) 378 return (error1); 379 return (error2); 380 } 381 382 /* 383 * Print out the contents of a fifo vnode. 384 */ 385 fifo_print(ap) 386 struct vop_print_args /* { 387 struct vnode *a_vp; 388 } */ *ap; 389 { 390 391 printf("tag VT_NON"); 392 fifo_printinfo(ap->a_vp); 393 printf("\n"); 394 } 395 396 /* 397 * Print out internal contents of a fifo vnode. 398 */ 399 fifo_printinfo(vp) 400 struct vnode *vp; 401 { 402 register struct fifoinfo *fip = vp->v_fifoinfo; 403 404 printf(", fifo with %d readers and %d writers", 405 fip->fi_readers, fip->fi_writers); 406 } 407 408 /* 409 * Fifo failed operation 410 */ 411 fifo_ebadf() 412 { 413 414 return (EBADF); 415 } 416 417 /* 418 * Fifo advisory byte-level locks. 419 */ 420 /* ARGSUSED */ 421 fifo_advlock(ap) 422 struct vop_advlock_args /* { 423 struct vnode *a_vp; 424 caddr_t a_id; 425 int a_op; 426 struct flock *a_fl; 427 int a_flags; 428 } */ *ap; 429 { 430 431 return (EOPNOTSUPP); 432 } 433 434 /* 435 * Fifo bad operation 436 */ 437 fifo_badop() 438 { 439 440 panic("fifo_badop called"); 441 /* NOTREACHED */ 442 } 443