1 /*- 2 * Copyright (c) 2000-2004 3 * Poul-Henning Kamp. All rights reserved. 4 * Copyright (c) 1989, 1992-1993, 1995 5 * The Regents of the University of California. All rights reserved. 6 * 7 * This code is derived from software donated to Berkeley by 8 * Jan-Simon Pendry. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Neither the name of the University nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 * 31 * @(#)kernfs_vnops.c 8.15 (Berkeley) 5/21/95 32 * From: FreeBSD: src/sys/miscfs/kernfs/kernfs_vnops.c 1.43 33 * 34 * $FreeBSD$ 35 */ 36 37 /* 38 * TODO: 39 * remove empty directories 40 * mknod: hunt down DE_DELETED, compare name, reinstantiate. 41 * mkdir: want it ? 42 */ 43 44 #include <opt_devfs.h> 45 #include <opt_mac.h> 46 47 #include <sys/param.h> 48 #include <sys/systm.h> 49 #include <sys/conf.h> 50 #include <sys/dirent.h> 51 #include <sys/fcntl.h> 52 #include <sys/file.h> 53 #include <sys/filedesc.h> 54 #include <sys/filio.h> 55 #include <sys/kernel.h> 56 #include <sys/lock.h> 57 #include <sys/mac.h> 58 #include <sys/malloc.h> 59 #include <sys/mount.h> 60 #include <sys/namei.h> 61 #include <sys/proc.h> 62 #include <sys/stat.h> 63 #include <sys/sx.h> 64 #include <sys/sysctl.h> 65 #include <sys/time.h> 66 #include <sys/ttycom.h> 67 #include <sys/unistd.h> 68 #include <sys/vnode.h> 69 70 #include <fs/devfs/devfs.h> 71 72 static fo_rdwr_t devfs_read_f; 73 static fo_rdwr_t devfs_write_f; 74 static fo_ioctl_t devfs_ioctl_f; 75 static fo_poll_t devfs_poll_f; 76 static fo_kqfilter_t devfs_kqfilter_f; 77 static fo_stat_t devfs_stat_f; 78 static fo_close_t devfs_close_f; 79 80 static struct fileops devfs_ops_f = { 81 .fo_read = devfs_read_f, 82 .fo_write = devfs_write_f, 83 .fo_ioctl = devfs_ioctl_f, 84 .fo_poll = devfs_poll_f, 85 .fo_kqfilter = devfs_kqfilter_f, 86 .fo_stat = devfs_stat_f, 87 .fo_close = devfs_close_f, 88 .fo_flags = DFLAG_PASSABLE | DFLAG_SEEKABLE 89 }; 90 91 static vop_access_t devfs_access; 92 static vop_advlock_t devfs_advlock; 93 static vop_close_t devfs_close; 94 static vop_fsync_t devfs_fsync; 95 static vop_getattr_t devfs_getattr; 96 static vop_lookup_t devfs_lookup; 97 static vop_lookup_t devfs_lookupx; 98 static vop_mknod_t devfs_mknod; 99 static vop_open_t devfs_open; 100 static vop_pathconf_t devfs_pathconf; 101 static vop_print_t devfs_print; 102 static vop_readdir_t devfs_readdir; 103 static vop_readlink_t devfs_readlink; 104 static vop_reclaim_t devfs_reclaim; 105 static vop_remove_t devfs_remove; 106 static vop_revoke_t devfs_revoke; 107 static vop_ioctl_t devfs_rioctl; 108 static vop_read_t devfs_rread; 109 static vop_setattr_t devfs_setattr; 110 #ifdef MAC 111 static vop_setlabel_t devfs_setlabel; 112 #endif 113 static vop_symlink_t devfs_symlink; 114 115 static struct vop_vector devfs_vnodeops = { 116 .vop_default = &default_vnodeops, 117 118 .vop_access = devfs_access, 119 .vop_getattr = devfs_getattr, 120 .vop_ioctl = devfs_rioctl, 121 .vop_lookup = devfs_lookup, 122 .vop_mknod = devfs_mknod, 123 .vop_pathconf = devfs_pathconf, 124 .vop_read = devfs_rread, 125 .vop_readdir = devfs_readdir, 126 .vop_readlink = devfs_readlink, 127 .vop_reclaim = devfs_reclaim, 128 .vop_remove = devfs_remove, 129 .vop_revoke = devfs_revoke, 130 .vop_setattr = devfs_setattr, 131 #ifdef MAC 132 .vop_setlabel = devfs_setlabel, 133 #endif 134 .vop_symlink = devfs_symlink, 135 }; 136 137 static struct vop_vector devfs_specops = { 138 .vop_default = &default_vnodeops, 139 140 .vop_access = devfs_access, 141 .vop_advlock = devfs_advlock, 142 .vop_bmap = VOP_PANIC, 143 .vop_close = devfs_close, 144 .vop_create = VOP_PANIC, 145 .vop_fsync = devfs_fsync, 146 .vop_getattr = devfs_getattr, 147 .vop_lease = VOP_NULL, 148 .vop_link = VOP_PANIC, 149 .vop_mkdir = VOP_PANIC, 150 .vop_mknod = VOP_PANIC, 151 .vop_open = devfs_open, 152 .vop_pathconf = devfs_pathconf, 153 .vop_print = devfs_print, 154 .vop_read = VOP_PANIC, 155 .vop_readdir = VOP_PANIC, 156 .vop_readlink = VOP_PANIC, 157 .vop_reallocblks = VOP_PANIC, 158 .vop_reclaim = devfs_reclaim, 159 .vop_remove = devfs_remove, 160 .vop_rename = VOP_PANIC, 161 .vop_revoke = devfs_revoke, 162 .vop_rmdir = VOP_PANIC, 163 .vop_setattr = devfs_setattr, 164 #ifdef MAC 165 .vop_setlabel = devfs_setlabel, 166 #endif 167 .vop_strategy = VOP_PANIC, 168 .vop_symlink = VOP_PANIC, 169 .vop_write = VOP_PANIC, 170 }; 171 172 static u_int 173 devfs_random(void) 174 { 175 static u_int devfs_seed; 176 177 while (devfs_seed == 0) { 178 /* 179 * Make sure people don't make stupid assumptions 180 * about device major/minor numbers in userspace. 181 * We do this late to get entropy and for the same 182 * reason we force a reseed, but it may not be 183 * late enough for entropy to be available. 184 */ 185 arc4rand(&devfs_seed, sizeof devfs_seed, 1); 186 devfs_seed &= 0xf0f; 187 } 188 return (devfs_seed); 189 } 190 191 static int 192 devfs_fp_check(struct file *fp, struct cdev **devp, struct cdevsw **dswp) 193 { 194 195 *devp = fp->f_vnode->v_rdev; 196 if (*devp != fp->f_data) 197 return (ENXIO); 198 KASSERT((*devp)->si_refcount > 0, 199 ("devfs: un-referenced struct cdev *(%s)", devtoname(*devp))); 200 *dswp = dev_refthread(*devp); 201 if (*dswp == NULL) 202 return (ENXIO); 203 return (0); 204 } 205 206 /* 207 * Construct the fully qualified path name relative to the mountpoint 208 */ 209 static char * 210 devfs_fqpn(char *buf, struct vnode *dvp, struct componentname *cnp) 211 { 212 int i; 213 struct devfs_dirent *de, *dd; 214 struct devfs_mount *dmp; 215 216 dmp = VFSTODEVFS(dvp->v_mount); 217 dd = dvp->v_data; 218 i = SPECNAMELEN; 219 buf[i] = '\0'; 220 i -= cnp->cn_namelen; 221 if (i < 0) 222 return (NULL); 223 bcopy(cnp->cn_nameptr, buf + i, cnp->cn_namelen); 224 de = dd; 225 while (de != dmp->dm_basedir) { 226 i--; 227 if (i < 0) 228 return (NULL); 229 buf[i] = '/'; 230 i -= de->de_dirent->d_namlen; 231 if (i < 0) 232 return (NULL); 233 bcopy(de->de_dirent->d_name, buf + i, 234 de->de_dirent->d_namlen); 235 de = TAILQ_FIRST(&de->de_dlist); /* "." */ 236 de = TAILQ_NEXT(de, de_list); /* ".." */ 237 de = de->de_dir; 238 } 239 return (buf + i); 240 } 241 242 int 243 devfs_allocv(struct devfs_dirent *de, struct mount *mp, struct vnode **vpp, struct thread *td) 244 { 245 int error; 246 struct vnode *vp; 247 struct cdev *dev; 248 249 KASSERT(td == curthread, ("devfs_allocv: td != curthread")); 250 loop: 251 vp = de->de_vnode; 252 if (vp != NULL) { 253 if (vget(vp, LK_EXCLUSIVE, td)) 254 goto loop; 255 *vpp = vp; 256 return (0); 257 } 258 if (de->de_dirent->d_type == DT_CHR) { 259 dev = *devfs_itod(de->de_inode); 260 if (dev == NULL) 261 return (ENOENT); 262 } else { 263 dev = NULL; 264 } 265 error = getnewvnode("devfs", mp, &devfs_vnodeops, &vp); 266 if (error != 0) { 267 printf("devfs_allocv: failed to allocate new vnode\n"); 268 return (error); 269 } 270 271 if (de->de_dirent->d_type == DT_CHR) { 272 vp->v_type = VCHR; 273 VI_LOCK(vp); 274 dev_lock(); 275 dev_refl(dev); 276 vp->v_rdev = dev; 277 LIST_INSERT_HEAD(&dev->si_alist, de, de_alias); 278 dev->si_usecount += vp->v_usecount; 279 dev_unlock(); 280 VI_UNLOCK(vp); 281 vp->v_op = &devfs_specops; 282 } else if (de->de_dirent->d_type == DT_DIR) { 283 vp->v_type = VDIR; 284 } else if (de->de_dirent->d_type == DT_LNK) { 285 vp->v_type = VLNK; 286 } else { 287 vp->v_type = VBAD; 288 } 289 vp->v_data = de; 290 de->de_vnode = vp; 291 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, td); 292 #ifdef MAC 293 mac_associate_vnode_devfs(mp, de, vp); 294 #endif 295 *vpp = vp; 296 return (0); 297 } 298 299 static int 300 devfs_access(ap) 301 struct vop_access_args /* { 302 struct vnode *a_vp; 303 int a_mode; 304 struct ucred *a_cred; 305 struct thread *a_td; 306 } */ *ap; 307 { 308 struct vnode *vp = ap->a_vp; 309 struct devfs_dirent *de; 310 int error; 311 312 de = vp->v_data; 313 if (vp->v_type == VDIR) 314 de = de->de_dir; 315 316 error = vaccess(vp->v_type, de->de_mode, de->de_uid, de->de_gid, 317 ap->a_mode, ap->a_cred, NULL); 318 if (!error) 319 return (error); 320 if (error != EACCES) 321 return (error); 322 /* We do, however, allow access to the controlling terminal */ 323 if (!(ap->a_td->td_proc->p_flag & P_CONTROLT)) 324 return (error); 325 if (ap->a_td->td_proc->p_session->s_ttyvp == de->de_vnode) 326 return (0); 327 return (error); 328 } 329 330 /* 331 * Special device advisory byte-level locks. 332 */ 333 /* ARGSUSED */ 334 static int 335 devfs_advlock(ap) 336 struct vop_advlock_args /* { 337 struct vnode *a_vp; 338 caddr_t a_id; 339 int a_op; 340 struct flock *a_fl; 341 int a_flags; 342 } */ *ap; 343 { 344 345 return (ap->a_flags & F_FLOCK ? EOPNOTSUPP : EINVAL); 346 } 347 348 /* 349 * Device close routine 350 */ 351 /* ARGSUSED */ 352 static int 353 devfs_close(ap) 354 struct vop_close_args /* { 355 struct vnode *a_vp; 356 int a_fflag; 357 struct ucred *a_cred; 358 struct thread *a_td; 359 } */ *ap; 360 { 361 struct vnode *vp = ap->a_vp, *oldvp; 362 struct thread *td = ap->a_td; 363 struct cdev *dev = vp->v_rdev; 364 struct cdevsw *dsw; 365 int error; 366 367 /* 368 * Hack: a tty device that is a controlling terminal 369 * has a reference from the session structure. 370 * We cannot easily tell that a character device is 371 * a controlling terminal, unless it is the closing 372 * process' controlling terminal. In that case, 373 * if the reference count is 2 (this last descriptor 374 * plus the session), release the reference from the session. 375 */ 376 377 /* 378 * This needs to be rewritten to take the vp interlock into 379 * consideration. 380 */ 381 382 oldvp = NULL; 383 sx_xlock(&proctree_lock); 384 if (td && vp == td->td_proc->p_session->s_ttyvp) { 385 SESS_LOCK(td->td_proc->p_session); 386 VI_LOCK(vp); 387 if (count_dev(dev) == 2 && (vp->v_iflag & VI_DOOMED) == 0) { 388 td->td_proc->p_session->s_ttyvp = NULL; 389 oldvp = vp; 390 } 391 VI_UNLOCK(vp); 392 SESS_UNLOCK(td->td_proc->p_session); 393 } 394 sx_xunlock(&proctree_lock); 395 if (oldvp != NULL) 396 vrele(oldvp); 397 /* 398 * We do not want to really close the device if it 399 * is still in use unless we are trying to close it 400 * forcibly. Since every use (buffer, vnode, swap, cmap) 401 * holds a reference to the vnode, and because we mark 402 * any other vnodes that alias this device, when the 403 * sum of the reference counts on all the aliased 404 * vnodes descends to one, we are on last close. 405 */ 406 dsw = dev_refthread(dev); 407 if (dsw == NULL) 408 return (ENXIO); 409 VI_LOCK(vp); 410 if (vp->v_iflag & VI_DOOMED) { 411 /* Forced close. */ 412 } else if (dsw->d_flags & D_TRACKCLOSE) { 413 /* Keep device updated on status. */ 414 } else if (count_dev(dev) > 1) { 415 VI_UNLOCK(vp); 416 dev_relthread(dev); 417 return (0); 418 } 419 VI_UNLOCK(vp); 420 KASSERT(dev->si_refcount > 0, 421 ("devfs_close() on un-referenced struct cdev *(%s)", devtoname(dev))); 422 if (!(dsw->d_flags & D_NEEDGIANT)) { 423 DROP_GIANT(); 424 error = dsw->d_close(dev, ap->a_fflag, S_IFCHR, td); 425 PICKUP_GIANT(); 426 } else { 427 mtx_lock(&Giant); 428 error = dsw->d_close(dev, ap->a_fflag, S_IFCHR, td); 429 mtx_unlock(&Giant); 430 } 431 dev_relthread(dev); 432 return (error); 433 } 434 435 static int 436 devfs_close_f(struct file *fp, struct thread *td) 437 { 438 439 return (vnops.fo_close(fp, td)); 440 } 441 442 /* 443 * Synch buffers associated with a block device 444 */ 445 /* ARGSUSED */ 446 static int 447 devfs_fsync(ap) 448 struct vop_fsync_args /* { 449 struct vnode *a_vp; 450 struct ucred *a_cred; 451 int a_waitfor; 452 struct thread *a_td; 453 } */ *ap; 454 { 455 if (!vn_isdisk(ap->a_vp, NULL)) 456 return (0); 457 458 return (vop_stdfsync(ap)); 459 } 460 461 static int 462 devfs_getattr(ap) 463 struct vop_getattr_args /* { 464 struct vnode *a_vp; 465 struct vattr *a_vap; 466 struct ucred *a_cred; 467 struct thread *a_td; 468 } */ *ap; 469 { 470 struct vnode *vp = ap->a_vp; 471 struct vattr *vap = ap->a_vap; 472 int error = 0; 473 struct devfs_dirent *de; 474 struct cdev *dev; 475 476 de = vp->v_data; 477 KASSERT(de != NULL, ("Null dirent in devfs_getattr vp=%p", vp)); 478 if (vp->v_type == VDIR) { 479 de = de->de_dir; 480 KASSERT(de != NULL, 481 ("Null dir dirent in devfs_getattr vp=%p", vp)); 482 } 483 bzero((caddr_t) vap, sizeof(*vap)); 484 vattr_null(vap); 485 vap->va_uid = de->de_uid; 486 vap->va_gid = de->de_gid; 487 vap->va_mode = de->de_mode; 488 if (vp->v_type == VLNK) 489 vap->va_size = strlen(de->de_symlink); 490 else if (vp->v_type == VDIR) 491 vap->va_size = vap->va_bytes = DEV_BSIZE; 492 else 493 vap->va_size = 0; 494 if (vp->v_type != VDIR) 495 vap->va_bytes = 0; 496 vap->va_blocksize = DEV_BSIZE; 497 vap->va_type = vp->v_type; 498 499 #define fix(aa) \ 500 do { \ 501 if ((aa).tv_sec == 0) { \ 502 (aa).tv_sec = boottime.tv_sec; \ 503 (aa).tv_nsec = boottime.tv_usec * 1000; \ 504 } \ 505 } while (0) 506 507 if (vp->v_type != VCHR) { 508 fix(de->de_atime); 509 vap->va_atime = de->de_atime; 510 fix(de->de_mtime); 511 vap->va_mtime = de->de_mtime; 512 fix(de->de_ctime); 513 vap->va_ctime = de->de_ctime; 514 } else { 515 dev = vp->v_rdev; 516 fix(dev->si_atime); 517 vap->va_atime = dev->si_atime; 518 fix(dev->si_mtime); 519 vap->va_mtime = dev->si_mtime; 520 fix(dev->si_ctime); 521 vap->va_ctime = dev->si_ctime; 522 523 vap->va_rdev = dev->si_inode ^ devfs_random(); 524 } 525 vap->va_gen = 0; 526 vap->va_flags = 0; 527 vap->va_nlink = de->de_links; 528 vap->va_fileid = de->de_inode; 529 530 return (error); 531 } 532 533 /* 534 * Device ioctl operation. 535 */ 536 /* ARGSUSED */ 537 static int 538 devfs_ioctl_f(struct file *fp, u_long com, void *data, struct ucred *cred, struct thread *td) 539 { 540 struct cdev *dev; 541 struct cdevsw *dsw; 542 struct vnode *vp; 543 struct vnode *vpold; 544 int error, i; 545 const char *p; 546 struct fiodgname_arg *fgn; 547 548 error = devfs_fp_check(fp, &dev, &dsw); 549 if (error) 550 return (error); 551 552 if (com == FIODTYPE) { 553 *(int *)data = dsw->d_flags & D_TYPEMASK; 554 dev_relthread(dev); 555 return (0); 556 } else if (com == FIODGNAME) { 557 fgn = data; 558 p = devtoname(dev); 559 i = strlen(p) + 1; 560 if (i > fgn->len) 561 return (EINVAL); 562 return (copyout(p, fgn->buf, i)); 563 } 564 if (dsw->d_flags & D_NEEDGIANT) 565 mtx_lock(&Giant); 566 error = dsw->d_ioctl(dev, com, data, fp->f_flag, td); 567 if (dsw->d_flags & D_NEEDGIANT) 568 mtx_unlock(&Giant); 569 dev_relthread(dev); 570 if (error == ENOIOCTL) 571 error = ENOTTY; 572 if (error == 0 && com == TIOCSCTTY) { 573 vp = fp->f_vnode; 574 575 /* Do nothing if reassigning same control tty */ 576 sx_slock(&proctree_lock); 577 if (td->td_proc->p_session->s_ttyvp == vp) { 578 sx_sunlock(&proctree_lock); 579 return (0); 580 } 581 582 mtx_lock(&Giant); 583 584 vpold = td->td_proc->p_session->s_ttyvp; 585 VREF(vp); 586 SESS_LOCK(td->td_proc->p_session); 587 td->td_proc->p_session->s_ttyvp = vp; 588 SESS_UNLOCK(td->td_proc->p_session); 589 590 sx_sunlock(&proctree_lock); 591 592 /* Get rid of reference to old control tty */ 593 if (vpold) 594 vrele(vpold); 595 mtx_unlock(&Giant); 596 } 597 return (error); 598 } 599 600 601 /* ARGSUSED */ 602 static int 603 devfs_kqfilter_f(struct file *fp, struct knote *kn) 604 { 605 struct cdev *dev; 606 struct cdevsw *dsw; 607 int error; 608 609 error = devfs_fp_check(fp, &dev, &dsw); 610 if (error) 611 return (error); 612 if (dsw->d_flags & D_NEEDGIANT) 613 mtx_lock(&Giant); 614 error = dsw->d_kqfilter(dev, kn); 615 if (dsw->d_flags & D_NEEDGIANT) 616 mtx_unlock(&Giant); 617 dev_relthread(dev); 618 return (error); 619 } 620 621 static int 622 devfs_lookupx(ap) 623 struct vop_lookup_args /* { 624 struct vnode * a_dvp; 625 struct vnode ** a_vpp; 626 struct componentname * a_cnp; 627 } */ *ap; 628 { 629 struct componentname *cnp; 630 struct vnode *dvp, **vpp; 631 struct thread *td; 632 struct devfs_dirent *de, *dd; 633 struct devfs_dirent **dde; 634 struct devfs_mount *dmp; 635 struct cdev *cdev; 636 int error, flags, nameiop; 637 char specname[SPECNAMELEN + 1], *pname; 638 639 cnp = ap->a_cnp; 640 vpp = ap->a_vpp; 641 dvp = ap->a_dvp; 642 pname = cnp->cn_nameptr; 643 td = cnp->cn_thread; 644 flags = cnp->cn_flags; 645 nameiop = cnp->cn_nameiop; 646 dmp = VFSTODEVFS(dvp->v_mount); 647 dd = dvp->v_data; 648 *vpp = NULLVP; 649 650 if ((flags & ISLASTCN) && nameiop == RENAME) 651 return (EOPNOTSUPP); 652 653 if (dvp->v_type != VDIR) 654 return (ENOTDIR); 655 656 if ((flags & ISDOTDOT) && (dvp->v_vflag & VV_ROOT)) 657 return (EIO); 658 659 error = VOP_ACCESS(dvp, VEXEC, cnp->cn_cred, td); 660 if (error) 661 return (error); 662 663 if (cnp->cn_namelen == 1 && *pname == '.') { 664 if ((flags & ISLASTCN) && nameiop != LOOKUP) 665 return (EINVAL); 666 *vpp = dvp; 667 VREF(dvp); 668 return (0); 669 } 670 671 if (flags & ISDOTDOT) { 672 if ((flags & ISLASTCN) && nameiop != LOOKUP) 673 return (EINVAL); 674 VOP_UNLOCK(dvp, 0, td); 675 de = TAILQ_FIRST(&dd->de_dlist); /* "." */ 676 de = TAILQ_NEXT(de, de_list); /* ".." */ 677 de = de->de_dir; 678 error = devfs_allocv(de, dvp->v_mount, vpp, td); 679 vn_lock(dvp, LK_EXCLUSIVE | LK_RETRY, td); 680 return (error); 681 } 682 683 devfs_populate(dmp); 684 dd = dvp->v_data; 685 TAILQ_FOREACH(de, &dd->de_dlist, de_list) { 686 if (cnp->cn_namelen != de->de_dirent->d_namlen) 687 continue; 688 if (bcmp(cnp->cn_nameptr, de->de_dirent->d_name, 689 de->de_dirent->d_namlen) != 0) 690 continue; 691 if (de->de_flags & DE_WHITEOUT) 692 goto notfound; 693 goto found; 694 } 695 696 if (nameiop == DELETE) 697 goto notfound; 698 699 /* 700 * OK, we didn't have an entry for the name we were asked for 701 * so we try to see if anybody can create it on demand. 702 */ 703 pname = devfs_fqpn(specname, dvp, cnp); 704 if (pname == NULL) 705 goto notfound; 706 707 cdev = NULL; 708 EVENTHANDLER_INVOKE(dev_clone, pname, strlen(pname), &cdev); 709 if (cdev == NULL) 710 goto notfound; 711 712 devfs_populate(dmp); 713 714 dde = devfs_itode(dmp, cdev->si_inode); 715 dev_rel(cdev); 716 717 if (dde == NULL || *dde == NULL || *dde == DE_DELETED) 718 goto notfound; 719 720 if ((*dde)->de_flags & DE_WHITEOUT) 721 goto notfound; 722 723 de = *dde; 724 goto found; 725 726 notfound: 727 728 if ((nameiop == CREATE || nameiop == RENAME) && 729 (flags & (LOCKPARENT | WANTPARENT)) && (flags & ISLASTCN)) { 730 cnp->cn_flags |= SAVENAME; 731 return (EJUSTRETURN); 732 } 733 return (ENOENT); 734 735 736 found: 737 738 if ((cnp->cn_nameiop == DELETE) && (flags & ISLASTCN)) { 739 error = VOP_ACCESS(dvp, VWRITE, cnp->cn_cred, td); 740 if (error) 741 return (error); 742 if (*vpp == dvp) { 743 VREF(dvp); 744 *vpp = dvp; 745 return (0); 746 } 747 error = devfs_allocv(de, dvp->v_mount, vpp, td); 748 if (error) 749 return (error); 750 return (0); 751 } 752 error = devfs_allocv(de, dvp->v_mount, vpp, td); 753 return (error); 754 } 755 756 static int 757 devfs_lookup(struct vop_lookup_args *ap) 758 { 759 int j; 760 struct devfs_mount *dmp; 761 762 dmp = VFSTODEVFS(ap->a_dvp->v_mount); 763 lockmgr(&dmp->dm_lock, LK_SHARED, 0, curthread); 764 j = devfs_lookupx(ap); 765 lockmgr(&dmp->dm_lock, LK_RELEASE, 0, curthread); 766 return (j); 767 } 768 769 static int 770 devfs_mknod(struct vop_mknod_args *ap) 771 /* 772 struct vop_mknod_args { 773 struct vnodeop_desc *a_desc; 774 struct vnode *a_dvp; 775 struct vnode **a_vpp; 776 struct componentname *a_cnp; 777 struct vattr *a_vap; 778 }; */ 779 { 780 struct componentname *cnp; 781 struct vnode *dvp, **vpp; 782 struct thread *td; 783 struct devfs_dirent *dd, *de; 784 struct devfs_mount *dmp; 785 int error; 786 787 dvp = ap->a_dvp; 788 dmp = VFSTODEVFS(dvp->v_mount); 789 lockmgr(&dmp->dm_lock, LK_EXCLUSIVE, 0, curthread); 790 791 cnp = ap->a_cnp; 792 vpp = ap->a_vpp; 793 td = cnp->cn_thread; 794 dd = dvp->v_data; 795 796 error = ENOENT; 797 TAILQ_FOREACH(de, &dd->de_dlist, de_list) { 798 if (cnp->cn_namelen != de->de_dirent->d_namlen) 799 continue; 800 if (bcmp(cnp->cn_nameptr, de->de_dirent->d_name, 801 de->de_dirent->d_namlen) != 0) 802 continue; 803 if (de->de_flags & DE_WHITEOUT) 804 break; 805 goto notfound; 806 } 807 if (de == NULL) 808 goto notfound; 809 de->de_flags &= ~DE_WHITEOUT; 810 error = devfs_allocv(de, dvp->v_mount, vpp, td); 811 notfound: 812 lockmgr(&dmp->dm_lock, LK_RELEASE, 0, curthread); 813 return (error); 814 } 815 816 /* 817 * Open a special file. 818 */ 819 /* ARGSUSED */ 820 static int 821 devfs_open(ap) 822 struct vop_open_args /* { 823 struct vnode *a_vp; 824 int a_mode; 825 struct ucred *a_cred; 826 struct thread *a_td; 827 int a_fdidx; 828 } */ *ap; 829 { 830 struct thread *td = ap->a_td; 831 struct vnode *vp = ap->a_vp; 832 struct cdev *dev = vp->v_rdev; 833 struct file *fp; 834 int error; 835 struct cdevsw *dsw; 836 837 if (vp->v_type == VBLK) 838 return (ENXIO); 839 840 if (dev == NULL) 841 return (ENXIO); 842 843 /* Make this field valid before any I/O in d_open. */ 844 if (dev->si_iosize_max == 0) 845 dev->si_iosize_max = DFLTPHYS; 846 847 if (vn_isdisk(vp, NULL) && 848 ap->a_cred != FSCRED && (ap->a_mode & FWRITE)) { 849 /* 850 * When running in very secure mode, do not allow 851 * opens for writing of any disks. 852 * XXX: should be in geom_dev.c, but we lack the cred there. 853 */ 854 error = securelevel_ge(td->td_ucred, 2); 855 if (error) 856 return (error); 857 } 858 859 dsw = dev_refthread(dev); 860 if (dsw == NULL) 861 return (ENXIO); 862 863 /* XXX: Special casing of ttys for deadfs. Probably redundant. */ 864 if (dsw->d_flags & D_TTY) 865 vp->v_vflag |= VV_ISTTY; 866 867 VOP_UNLOCK(vp, 0, td); 868 869 if(!(dsw->d_flags & D_NEEDGIANT)) { 870 DROP_GIANT(); 871 if (dsw->d_fdopen != NULL) 872 error = dsw->d_fdopen(dev, ap->a_mode, td, ap->a_fdidx); 873 else 874 error = dsw->d_open(dev, ap->a_mode, S_IFCHR, td); 875 PICKUP_GIANT(); 876 } else { 877 mtx_lock(&Giant); 878 if (dsw->d_fdopen != NULL) 879 error = dsw->d_fdopen(dev, ap->a_mode, td, ap->a_fdidx); 880 else 881 error = dsw->d_open(dev, ap->a_mode, S_IFCHR, td); 882 mtx_unlock(&Giant); 883 } 884 885 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, td); 886 887 dev_relthread(dev); 888 889 if (error) 890 return (error); 891 892 #if 0 /* /dev/console */ 893 KASSERT(ap->a_fdidx >= 0, 894 ("Could not vnode bypass device on fd %d", ap->a_fdidx)); 895 #else 896 if(ap->a_fdidx < 0) 897 return (error); 898 #endif 899 /* 900 * This is a pretty disgustingly long chain, but I am not 901 * sure there is any better way. Passing the fdidx into 902 * VOP_OPEN() offers us more information than just passing 903 * the file *. 904 */ 905 fp = ap->a_td->td_proc->p_fd->fd_ofiles[ap->a_fdidx]; 906 KASSERT(fp->f_ops == &badfileops, 907 ("Could not vnode bypass device on fdops %p", fp->f_ops)); 908 fp->f_ops = &devfs_ops_f; 909 fp->f_data = dev; 910 return (error); 911 } 912 913 static int 914 devfs_pathconf(ap) 915 struct vop_pathconf_args /* { 916 struct vnode *a_vp; 917 int a_name; 918 int *a_retval; 919 } */ *ap; 920 { 921 922 switch (ap->a_name) { 923 case _PC_NAME_MAX: 924 *ap->a_retval = NAME_MAX; 925 return (0); 926 case _PC_PATH_MAX: 927 *ap->a_retval = PATH_MAX; 928 return (0); 929 case _PC_MAC_PRESENT: 930 #ifdef MAC 931 /* 932 * If MAC is enabled, devfs automatically supports 933 * trivial non-persistant label storage. 934 */ 935 *ap->a_retval = 1; 936 #else 937 *ap->a_retval = 0; 938 #endif 939 return (0); 940 default: 941 return (vop_stdpathconf(ap)); 942 } 943 /* NOTREACHED */ 944 } 945 946 /* ARGSUSED */ 947 static int 948 devfs_poll_f(struct file *fp, int events, struct ucred *cred, struct thread *td) 949 { 950 struct cdev *dev; 951 struct cdevsw *dsw; 952 int error; 953 954 error = devfs_fp_check(fp, &dev, &dsw); 955 if (error) 956 return (error); 957 if (dsw->d_flags & D_NEEDGIANT) 958 mtx_lock(&Giant); 959 error = dsw->d_poll(dev, events, td); 960 if (dsw->d_flags & D_NEEDGIANT) 961 mtx_unlock(&Giant); 962 dev_relthread(dev); 963 return(error); 964 } 965 966 /* 967 * Print out the contents of a special device vnode. 968 */ 969 static int 970 devfs_print(ap) 971 struct vop_print_args /* { 972 struct vnode *a_vp; 973 } */ *ap; 974 { 975 976 printf("\tdev %s\n", devtoname(ap->a_vp->v_rdev)); 977 return (0); 978 } 979 980 /* 981 * Vnode op for read 982 */ 983 /* ARGSUSED */ 984 static int 985 devfs_read_f(struct file *fp, struct uio *uio, struct ucred *cred, int flags, struct thread *td) 986 { 987 struct cdev *dev; 988 int ioflag, error, resid; 989 struct cdevsw *dsw; 990 991 error = devfs_fp_check(fp, &dev, &dsw); 992 if (error) 993 return (error); 994 resid = uio->uio_resid; 995 ioflag = fp->f_flag & (O_NONBLOCK | O_DIRECT); 996 if (ioflag & O_DIRECT) 997 ioflag |= IO_DIRECT; 998 999 if ((flags & FOF_OFFSET) == 0) 1000 uio->uio_offset = fp->f_offset; 1001 1002 if (dsw->d_flags & D_NEEDGIANT) 1003 mtx_lock(&Giant); 1004 error = dsw->d_read(dev, uio, ioflag); 1005 if (dsw->d_flags & D_NEEDGIANT) 1006 mtx_unlock(&Giant); 1007 dev_relthread(dev); 1008 if (uio->uio_resid != resid || (error == 0 && resid != 0)) 1009 vfs_timestamp(&dev->si_atime); 1010 1011 if ((flags & FOF_OFFSET) == 0) 1012 fp->f_offset = uio->uio_offset; 1013 fp->f_nextoff = uio->uio_offset; 1014 return (error); 1015 } 1016 1017 static int 1018 devfs_readdir(ap) 1019 struct vop_readdir_args /* { 1020 struct vnode *a_vp; 1021 struct uio *a_uio; 1022 struct ucred *a_cred; 1023 int *a_eofflag; 1024 int *a_ncookies; 1025 u_long **a_cookies; 1026 } */ *ap; 1027 { 1028 int error; 1029 struct uio *uio; 1030 struct dirent *dp; 1031 struct devfs_dirent *dd; 1032 struct devfs_dirent *de; 1033 struct devfs_mount *dmp; 1034 off_t off, oldoff; 1035 int ncookies = 0; 1036 u_long *cookiebuf, *cookiep; 1037 struct dirent *dps, *dpe; 1038 1039 if (ap->a_vp->v_type != VDIR) 1040 return (ENOTDIR); 1041 1042 uio = ap->a_uio; 1043 if (uio->uio_offset < 0) 1044 return (EINVAL); 1045 1046 dmp = VFSTODEVFS(ap->a_vp->v_mount); 1047 lockmgr(&dmp->dm_lock, LK_SHARED, 0, curthread); 1048 devfs_populate(dmp); 1049 error = 0; 1050 de = ap->a_vp->v_data; 1051 off = 0; 1052 oldoff = uio->uio_offset; 1053 TAILQ_FOREACH(dd, &de->de_dlist, de_list) { 1054 if (dd->de_flags & DE_WHITEOUT) 1055 continue; 1056 if (dd->de_dirent->d_type == DT_DIR) 1057 de = dd->de_dir; 1058 else 1059 de = dd; 1060 dp = dd->de_dirent; 1061 if (dp->d_reclen > uio->uio_resid) 1062 break; 1063 dp->d_fileno = de->de_inode; 1064 if (off >= uio->uio_offset) { 1065 ncookies++; 1066 error = uiomove(dp, dp->d_reclen, uio); 1067 if (error) 1068 break; 1069 } 1070 off += dp->d_reclen; 1071 } 1072 if( !error && ap->a_ncookies != NULL && ap->a_cookies != NULL ) { 1073 MALLOC(cookiebuf, u_long *, ncookies * sizeof(u_long), 1074 M_TEMP, M_WAITOK); 1075 cookiep = cookiebuf; 1076 dps = (struct dirent *)((char *)uio->uio_iov->iov_base - 1077 (uio->uio_offset - oldoff)); 1078 dpe = (struct dirent *) uio->uio_iov->iov_base; 1079 for( dp = dps; 1080 dp < dpe; 1081 dp = (struct dirent *)((caddr_t) dp + dp->d_reclen)) { 1082 oldoff += dp->d_reclen; 1083 *cookiep++ = (u_long) oldoff; 1084 } 1085 *ap->a_ncookies = ncookies; 1086 *ap->a_cookies = cookiebuf; 1087 } 1088 lockmgr(&dmp->dm_lock, LK_RELEASE, 0, curthread); 1089 uio->uio_offset = off; 1090 return (error); 1091 } 1092 1093 static int 1094 devfs_readlink(ap) 1095 struct vop_readlink_args /* { 1096 struct vnode *a_vp; 1097 struct uio *a_uio; 1098 struct ucred *a_cead; 1099 } */ *ap; 1100 { 1101 int error; 1102 struct devfs_dirent *de; 1103 1104 de = ap->a_vp->v_data; 1105 error = uiomove(de->de_symlink, strlen(de->de_symlink), ap->a_uio); 1106 return (error); 1107 } 1108 1109 static int 1110 devfs_reclaim(ap) 1111 struct vop_reclaim_args /* { 1112 struct vnode *a_vp; 1113 } */ *ap; 1114 { 1115 struct vnode *vp = ap->a_vp; 1116 struct devfs_dirent *de; 1117 struct cdev *dev; 1118 1119 de = vp->v_data; 1120 if (de != NULL) 1121 de->de_vnode = NULL; 1122 vp->v_data = NULL; 1123 vnode_destroy_vobject(vp); 1124 1125 dev = vp->v_rdev; 1126 vp->v_rdev = NULL; 1127 1128 if (dev == NULL) 1129 return (0); 1130 1131 dev_lock(); 1132 if (de != NULL) 1133 LIST_REMOVE(de, de_alias); 1134 dev->si_usecount -= vp->v_usecount; 1135 dev_unlock(); 1136 dev_rel(dev); 1137 return (0); 1138 } 1139 1140 static int 1141 devfs_remove(ap) 1142 struct vop_remove_args /* { 1143 struct vnode *a_dvp; 1144 struct vnode *a_vp; 1145 struct componentname *a_cnp; 1146 } */ *ap; 1147 { 1148 struct vnode *vp = ap->a_vp; 1149 struct devfs_dirent *dd; 1150 struct devfs_dirent *de; 1151 struct devfs_mount *dmp = VFSTODEVFS(vp->v_mount); 1152 1153 lockmgr(&dmp->dm_lock, LK_EXCLUSIVE, 0, curthread); 1154 dd = ap->a_dvp->v_data; 1155 de = vp->v_data; 1156 if (de->de_dirent->d_type == DT_LNK) { 1157 TAILQ_REMOVE(&dd->de_dlist, de, de_list); 1158 if (de->de_vnode) 1159 de->de_vnode->v_data = NULL; 1160 #ifdef MAC 1161 mac_destroy_devfsdirent(de); 1162 #endif 1163 FREE(de, M_DEVFS); 1164 } else { 1165 de->de_flags |= DE_WHITEOUT; 1166 } 1167 lockmgr(&dmp->dm_lock, LK_RELEASE, 0, curthread); 1168 return (0); 1169 } 1170 1171 /* 1172 * Revoke is called on a tty when a terminal session ends. The vnode 1173 * is orphaned by setting v_op to deadfs so we need to let go of it 1174 * as well so that we create a new one next time around. 1175 */ 1176 static int 1177 devfs_revoke(ap) 1178 struct vop_revoke_args /* { 1179 struct vnode *a_vp; 1180 int a_flags; 1181 } */ *ap; 1182 { 1183 struct vnode *vp = ap->a_vp; 1184 struct cdev *dev; 1185 struct devfs_dirent *de; 1186 1187 KASSERT((ap->a_flags & REVOKEALL) != 0, ("devfs_revoke !REVOKEALL")); 1188 1189 dev = vp->v_rdev; 1190 for (;;) { 1191 dev_lock(); 1192 de = LIST_FIRST(&dev->si_alist); 1193 dev_unlock(); 1194 if (de == NULL) 1195 break; 1196 vgone(de->de_vnode); 1197 } 1198 return (0); 1199 } 1200 1201 static int 1202 devfs_rioctl(ap) 1203 struct vop_ioctl_args /* { 1204 struct vnode *a_vp; 1205 u_long a_command; 1206 caddr_t a_data; 1207 int a_fflag; 1208 struct ucred *a_cred; 1209 struct thread *a_td; 1210 } */ *ap; 1211 { 1212 int error; 1213 struct devfs_mount *dmp; 1214 1215 dmp = VFSTODEVFS(ap->a_vp->v_mount); 1216 lockmgr(&dmp->dm_lock, LK_SHARED, 0, curthread); 1217 devfs_populate(dmp); 1218 lockmgr(&dmp->dm_lock, LK_RELEASE, 0, curthread); 1219 error = devfs_rules_ioctl(ap->a_vp->v_mount, ap->a_command, ap->a_data, 1220 ap->a_td); 1221 return (error); 1222 } 1223 1224 static int 1225 devfs_rread(ap) 1226 struct vop_read_args /* { 1227 struct vnode *a_vp; 1228 struct uio *a_uio; 1229 int a_ioflag; 1230 struct ucred *a_cred; 1231 } */ *ap; 1232 { 1233 1234 if (ap->a_vp->v_type != VDIR) 1235 return (EINVAL); 1236 return (VOP_READDIR(ap->a_vp, ap->a_uio, ap->a_cred, NULL, NULL, NULL)); 1237 } 1238 1239 static int 1240 devfs_setattr(ap) 1241 struct vop_setattr_args /* { 1242 struct vnode *a_vp; 1243 struct vattr *a_vap; 1244 struct ucred *a_cred; 1245 struct proc *a_p; 1246 } */ *ap; 1247 { 1248 struct devfs_dirent *de; 1249 struct vattr *vap; 1250 struct vnode *vp; 1251 int c, error; 1252 uid_t uid; 1253 gid_t gid; 1254 1255 vap = ap->a_vap; 1256 vp = ap->a_vp; 1257 if ((vap->va_type != VNON) || 1258 (vap->va_nlink != VNOVAL) || 1259 (vap->va_fsid != VNOVAL) || 1260 (vap->va_fileid != VNOVAL) || 1261 (vap->va_blocksize != VNOVAL) || 1262 (vap->va_flags != VNOVAL && vap->va_flags != 0) || 1263 (vap->va_rdev != VNOVAL) || 1264 ((int)vap->va_bytes != VNOVAL) || 1265 (vap->va_gen != VNOVAL)) { 1266 return (EINVAL); 1267 } 1268 1269 de = vp->v_data; 1270 if (vp->v_type == VDIR) 1271 de = de->de_dir; 1272 1273 error = c = 0; 1274 if (vap->va_uid == (uid_t)VNOVAL) 1275 uid = de->de_uid; 1276 else 1277 uid = vap->va_uid; 1278 if (vap->va_gid == (gid_t)VNOVAL) 1279 gid = de->de_gid; 1280 else 1281 gid = vap->va_gid; 1282 if (uid != de->de_uid || gid != de->de_gid) { 1283 if (((ap->a_cred->cr_uid != de->de_uid) || uid != de->de_uid || 1284 (gid != de->de_gid && !groupmember(gid, ap->a_cred))) && 1285 (error = suser_cred(ap->a_td->td_ucred, SUSER_ALLOWJAIL)) != 0) 1286 return (error); 1287 de->de_uid = uid; 1288 de->de_gid = gid; 1289 c = 1; 1290 } 1291 1292 if (vap->va_mode != (mode_t)VNOVAL) { 1293 if ((ap->a_cred->cr_uid != de->de_uid) && 1294 (error = suser_cred(ap->a_td->td_ucred, SUSER_ALLOWJAIL))) 1295 return (error); 1296 de->de_mode = vap->va_mode; 1297 c = 1; 1298 } 1299 1300 if (vap->va_atime.tv_sec != VNOVAL || vap->va_mtime.tv_sec != VNOVAL) { 1301 /* See the comment in ufs_vnops::ufs_setattr(). */ 1302 if ((error = VOP_ACCESS(vp, VADMIN, ap->a_cred, ap->a_td)) && 1303 ((vap->va_vaflags & VA_UTIMES_NULL) == 0 || 1304 (error = VOP_ACCESS(vp, VWRITE, ap->a_cred, ap->a_td)))) 1305 return (error); 1306 if (vap->va_atime.tv_sec != VNOVAL) { 1307 if (vp->v_type == VCHR) 1308 vp->v_rdev->si_atime = vap->va_atime; 1309 else 1310 de->de_atime = vap->va_atime; 1311 } 1312 if (vap->va_mtime.tv_sec != VNOVAL) { 1313 if (vp->v_type == VCHR) 1314 vp->v_rdev->si_mtime = vap->va_mtime; 1315 else 1316 de->de_mtime = vap->va_mtime; 1317 } 1318 c = 1; 1319 } 1320 1321 if (c) { 1322 if (vp->v_type == VCHR) 1323 vfs_timestamp(&vp->v_rdev->si_ctime); 1324 else 1325 vfs_timestamp(&de->de_mtime); 1326 } 1327 return (0); 1328 } 1329 1330 #ifdef MAC 1331 static int 1332 devfs_setlabel(ap) 1333 struct vop_setlabel_args /* { 1334 struct vnode *a_vp; 1335 struct mac *a_label; 1336 struct ucred *a_cred; 1337 struct thread *a_td; 1338 } */ *ap; 1339 { 1340 struct vnode *vp; 1341 struct devfs_dirent *de; 1342 1343 vp = ap->a_vp; 1344 de = vp->v_data; 1345 1346 mac_relabel_vnode(ap->a_cred, vp, ap->a_label); 1347 mac_update_devfsdirent(vp->v_mount, de, vp); 1348 1349 return (0); 1350 } 1351 #endif 1352 1353 static int 1354 devfs_stat_f(struct file *fp, struct stat *sb, struct ucred *cred, struct thread *td) 1355 { 1356 1357 return (vnops.fo_stat(fp, sb, cred, td)); 1358 } 1359 1360 static int 1361 devfs_symlink(ap) 1362 struct vop_symlink_args /* { 1363 struct vnode *a_dvp; 1364 struct vnode **a_vpp; 1365 struct componentname *a_cnp; 1366 struct vattr *a_vap; 1367 char *a_target; 1368 } */ *ap; 1369 { 1370 int i, error; 1371 struct devfs_dirent *dd; 1372 struct devfs_dirent *de; 1373 struct devfs_mount *dmp; 1374 struct thread *td; 1375 1376 td = ap->a_cnp->cn_thread; 1377 KASSERT(td == curthread, ("devfs_symlink: td != curthread")); 1378 error = suser(td); 1379 if (error) 1380 return(error); 1381 dmp = VFSTODEVFS(ap->a_dvp->v_mount); 1382 dd = ap->a_dvp->v_data; 1383 de = devfs_newdirent(ap->a_cnp->cn_nameptr, ap->a_cnp->cn_namelen); 1384 de->de_uid = 0; 1385 de->de_gid = 0; 1386 de->de_mode = 0755; 1387 de->de_inode = dmp->dm_inode++; 1388 de->de_dirent->d_type = DT_LNK; 1389 i = strlen(ap->a_target) + 1; 1390 MALLOC(de->de_symlink, char *, i, M_DEVFS, M_WAITOK); 1391 bcopy(ap->a_target, de->de_symlink, i); 1392 lockmgr(&dmp->dm_lock, LK_EXCLUSIVE, 0, td); 1393 #ifdef MAC 1394 mac_create_devfs_symlink(ap->a_cnp->cn_cred, dmp->dm_mount, dd, de); 1395 #endif 1396 TAILQ_INSERT_TAIL(&dd->de_dlist, de, de_list); 1397 devfs_allocv(de, ap->a_dvp->v_mount, ap->a_vpp, td); 1398 lockmgr(&dmp->dm_lock, LK_RELEASE, 0, td); 1399 return (0); 1400 } 1401 1402 /* 1403 * Vnode op for write 1404 */ 1405 /* ARGSUSED */ 1406 static int 1407 devfs_write_f(struct file *fp, struct uio *uio, struct ucred *cred, int flags, struct thread *td) 1408 { 1409 struct cdev *dev; 1410 struct vnode *vp; 1411 int error, ioflag, resid; 1412 struct cdevsw *dsw; 1413 1414 error = devfs_fp_check(fp, &dev, &dsw); 1415 if (error) 1416 return (error); 1417 KASSERT(uio->uio_td == td, ("uio_td %p is not td %p", uio->uio_td, td)); 1418 vp = fp->f_vnode; 1419 ioflag = fp->f_flag & (O_NONBLOCK | O_DIRECT | O_FSYNC); 1420 if (ioflag & O_DIRECT) 1421 ioflag |= IO_DIRECT; 1422 if ((flags & FOF_OFFSET) == 0) 1423 uio->uio_offset = fp->f_offset; 1424 1425 resid = uio->uio_resid; 1426 1427 if (dsw->d_flags & D_NEEDGIANT) 1428 mtx_lock(&Giant); 1429 error = dsw->d_write(dev, uio, ioflag); 1430 if (dsw->d_flags & D_NEEDGIANT) 1431 mtx_unlock(&Giant); 1432 dev_relthread(dev); 1433 if (uio->uio_resid != resid || (error == 0 && resid != 0)) { 1434 vfs_timestamp(&dev->si_ctime); 1435 dev->si_mtime = dev->si_ctime; 1436 } 1437 1438 if ((flags & FOF_OFFSET) == 0) 1439 fp->f_offset = uio->uio_offset; 1440 fp->f_nextoff = uio->uio_offset; 1441 return (error); 1442 } 1443 1444 dev_t 1445 dev2udev(struct cdev *x) 1446 { 1447 if (x == NULL) 1448 return (NODEV); 1449 return (x->si_inode ^ devfs_random()); 1450 } 1451 1452 /* 1453 * Helper sysctl for devname(3). We're given a struct cdev * and return 1454 * the name, if any, registered by the device driver. 1455 */ 1456 static int 1457 sysctl_devname(SYSCTL_HANDLER_ARGS) 1458 { 1459 int error; 1460 dev_t ud; 1461 struct cdev *dev, **dp; 1462 1463 error = SYSCTL_IN(req, &ud, sizeof (ud)); 1464 if (error) 1465 return (error); 1466 if (ud == NODEV) 1467 return(EINVAL); 1468 dp = devfs_itod(ud ^ devfs_random()); 1469 if (dp == NULL) 1470 return(ENOENT); 1471 dev = *dp; 1472 if (dev == NULL) 1473 return(ENOENT); 1474 return(SYSCTL_OUT(req, dev->si_name, strlen(dev->si_name) + 1)); 1475 return (error); 1476 } 1477 1478 SYSCTL_PROC(_kern, OID_AUTO, devname, CTLTYPE_OPAQUE|CTLFLAG_RW|CTLFLAG_ANYBODY, 1479 NULL, 0, sysctl_devname, "", "devname(3) handler"); 1480 1481 /* 1482 * Our calling convention to the device drivers used to be that we passed 1483 * vnode.h IO_* flags to read()/write(), but we're moving to fcntl.h O_ 1484 * flags instead since that's what open(), close() and ioctl() takes and 1485 * we don't really want vnode.h in device drivers. 1486 * We solved the source compatibility by redefining some vnode flags to 1487 * be the same as the fcntl ones and by sending down the bitwise OR of 1488 * the respective fcntl/vnode flags. These CTASSERTS make sure nobody 1489 * pulls the rug out under this. 1490 */ 1491 CTASSERT(O_NONBLOCK == IO_NDELAY); 1492 CTASSERT(O_FSYNC == IO_SYNC); 1493