1 /* 2 * (MPSAFE) 3 * 4 * Copyright (c) 2009 The DragonFly Project. All rights reserved. 5 * 6 * This code is derived from software contributed to The DragonFly Project 7 * by Alex Hornung <ahornung@gmail.com> 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in 17 * the documentation and/or other materials provided with the 18 * distribution. 19 * 3. Neither the name of The DragonFly Project nor the names of its 20 * contributors may be used to endorse or promote products derived 21 * from this software without specific, prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 24 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 25 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 26 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 27 * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 28 * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING, 29 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 30 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 31 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 32 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT 33 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 */ 36 #include <sys/param.h> 37 #include <sys/systm.h> 38 #include <sys/time.h> 39 #include <sys/kernel.h> 40 #include <sys/lock.h> 41 #include <sys/fcntl.h> 42 #include <sys/proc.h> 43 #include <sys/priv.h> 44 #include <sys/signalvar.h> 45 #include <sys/vnode.h> 46 #include <sys/uio.h> 47 #include <sys/mount.h> 48 #include <sys/file.h> 49 #include <sys/fcntl.h> 50 #include <sys/namei.h> 51 #include <sys/dirent.h> 52 #include <sys/malloc.h> 53 #include <sys/stat.h> 54 #include <sys/reg.h> 55 #include <vm/vm_pager.h> 56 #include <vm/vm_zone.h> 57 #include <vm/vm_object.h> 58 #include <sys/filio.h> 59 #include <sys/ttycom.h> 60 #include <sys/tty.h> 61 #include <sys/diskslice.h> 62 #include <sys/sysctl.h> 63 #include <sys/devfs.h> 64 #include <sys/pioctl.h> 65 #include <vfs/fifofs/fifo.h> 66 67 #include <machine/limits.h> 68 69 #include <sys/buf2.h> 70 #include <sys/sysref2.h> 71 #include <sys/mplock2.h> 72 #include <vm/vm_page2.h> 73 74 MALLOC_DECLARE(M_DEVFS); 75 #define DEVFS_BADOP (void *)devfs_vop_badop 76 77 static int devfs_vop_badop(struct vop_generic_args *); 78 static int devfs_vop_access(struct vop_access_args *); 79 static int devfs_vop_inactive(struct vop_inactive_args *); 80 static int devfs_vop_reclaim(struct vop_reclaim_args *); 81 static int devfs_vop_readdir(struct vop_readdir_args *); 82 static int devfs_vop_getattr(struct vop_getattr_args *); 83 static int devfs_vop_setattr(struct vop_setattr_args *); 84 static int devfs_vop_readlink(struct vop_readlink_args *); 85 static int devfs_vop_print(struct vop_print_args *); 86 87 static int devfs_vop_nresolve(struct vop_nresolve_args *); 88 static int devfs_vop_nlookupdotdot(struct vop_nlookupdotdot_args *); 89 static int devfs_vop_nmkdir(struct vop_nmkdir_args *); 90 static int devfs_vop_nsymlink(struct vop_nsymlink_args *); 91 static int devfs_vop_nrmdir(struct vop_nrmdir_args *); 92 static int devfs_vop_nremove(struct vop_nremove_args *); 93 94 static int devfs_spec_open(struct vop_open_args *); 95 static int devfs_spec_close(struct vop_close_args *); 96 static int devfs_spec_fsync(struct vop_fsync_args *); 97 98 static int devfs_spec_read(struct vop_read_args *); 99 static int devfs_spec_write(struct vop_write_args *); 100 static int devfs_spec_ioctl(struct vop_ioctl_args *); 101 static int devfs_spec_kqfilter(struct vop_kqfilter_args *); 102 static int devfs_spec_strategy(struct vop_strategy_args *); 103 static void devfs_spec_strategy_done(struct bio *); 104 static int devfs_spec_freeblks(struct vop_freeblks_args *); 105 static int devfs_spec_bmap(struct vop_bmap_args *); 106 static int devfs_spec_advlock(struct vop_advlock_args *); 107 static void devfs_spec_getpages_iodone(struct bio *); 108 static int devfs_spec_getpages(struct vop_getpages_args *); 109 110 static int devfs_fo_close(struct file *); 111 static int devfs_fo_read(struct file *, struct uio *, struct ucred *, int); 112 static int devfs_fo_write(struct file *, struct uio *, struct ucred *, int); 113 static int devfs_fo_stat(struct file *, struct stat *, struct ucred *); 114 static int devfs_fo_kqfilter(struct file *, struct knote *); 115 static int devfs_fo_ioctl(struct file *, u_long, caddr_t, 116 struct ucred *, struct sysmsg *); 117 static __inline int sequential_heuristic(struct uio *, struct file *); 118 119 extern struct lock devfs_lock; 120 121 /* 122 * devfs vnode operations for regular files. All vnode ops are MPSAFE. 123 */ 124 struct vop_ops devfs_vnode_norm_vops = { 125 .vop_default = vop_defaultop, 126 .vop_access = devfs_vop_access, 127 .vop_advlock = DEVFS_BADOP, 128 .vop_bmap = DEVFS_BADOP, 129 .vop_close = vop_stdclose, 130 .vop_getattr = devfs_vop_getattr, 131 .vop_inactive = devfs_vop_inactive, 132 .vop_ncreate = DEVFS_BADOP, 133 .vop_nresolve = devfs_vop_nresolve, 134 .vop_nlookupdotdot = devfs_vop_nlookupdotdot, 135 .vop_nlink = DEVFS_BADOP, 136 .vop_nmkdir = devfs_vop_nmkdir, 137 .vop_nmknod = DEVFS_BADOP, 138 .vop_nremove = devfs_vop_nremove, 139 .vop_nrename = DEVFS_BADOP, 140 .vop_nrmdir = devfs_vop_nrmdir, 141 .vop_nsymlink = devfs_vop_nsymlink, 142 .vop_open = vop_stdopen, 143 .vop_pathconf = vop_stdpathconf, 144 .vop_print = devfs_vop_print, 145 .vop_read = DEVFS_BADOP, 146 .vop_readdir = devfs_vop_readdir, 147 .vop_readlink = devfs_vop_readlink, 148 .vop_reclaim = devfs_vop_reclaim, 149 .vop_setattr = devfs_vop_setattr, 150 .vop_write = DEVFS_BADOP, 151 .vop_ioctl = DEVFS_BADOP 152 }; 153 154 /* 155 * devfs vnode operations for character devices. All vnode ops are MPSAFE. 156 */ 157 struct vop_ops devfs_vnode_dev_vops = { 158 .vop_default = vop_defaultop, 159 .vop_access = devfs_vop_access, 160 .vop_advlock = devfs_spec_advlock, 161 .vop_bmap = devfs_spec_bmap, 162 .vop_close = devfs_spec_close, 163 .vop_freeblks = devfs_spec_freeblks, 164 .vop_fsync = devfs_spec_fsync, 165 .vop_getattr = devfs_vop_getattr, 166 .vop_getpages = devfs_spec_getpages, 167 .vop_inactive = devfs_vop_inactive, 168 .vop_open = devfs_spec_open, 169 .vop_pathconf = vop_stdpathconf, 170 .vop_print = devfs_vop_print, 171 .vop_kqfilter = devfs_spec_kqfilter, 172 .vop_read = devfs_spec_read, 173 .vop_readdir = DEVFS_BADOP, 174 .vop_readlink = DEVFS_BADOP, 175 .vop_reclaim = devfs_vop_reclaim, 176 .vop_setattr = devfs_vop_setattr, 177 .vop_strategy = devfs_spec_strategy, 178 .vop_write = devfs_spec_write, 179 .vop_ioctl = devfs_spec_ioctl 180 }; 181 182 /* 183 * devfs file pointer operations. All fileops are MPSAFE. 184 */ 185 struct vop_ops *devfs_vnode_dev_vops_p = &devfs_vnode_dev_vops; 186 187 struct fileops devfs_dev_fileops = { 188 .fo_read = devfs_fo_read, 189 .fo_write = devfs_fo_write, 190 .fo_ioctl = devfs_fo_ioctl, 191 .fo_kqfilter = devfs_fo_kqfilter, 192 .fo_stat = devfs_fo_stat, 193 .fo_close = devfs_fo_close, 194 .fo_shutdown = nofo_shutdown 195 }; 196 197 /* 198 * These two functions are possibly temporary hacks for devices (aka 199 * the pty code) which want to control the node attributes themselves. 200 * 201 * XXX we may ultimately desire to simply remove the uid/gid/mode 202 * from the node entirely. 203 * 204 * MPSAFE - sorta. Theoretically the overwrite can compete since they 205 * are loading from the same fields. 206 */ 207 static __inline void 208 node_sync_dev_get(struct devfs_node *node) 209 { 210 cdev_t dev; 211 212 if ((dev = node->d_dev) && (dev->si_flags & SI_OVERRIDE)) { 213 node->uid = dev->si_uid; 214 node->gid = dev->si_gid; 215 node->mode = dev->si_perms; 216 } 217 } 218 219 static __inline void 220 node_sync_dev_set(struct devfs_node *node) 221 { 222 cdev_t dev; 223 224 if ((dev = node->d_dev) && (dev->si_flags & SI_OVERRIDE)) { 225 dev->si_uid = node->uid; 226 dev->si_gid = node->gid; 227 dev->si_perms = node->mode; 228 } 229 } 230 231 /* 232 * generic entry point for unsupported operations 233 */ 234 static int 235 devfs_vop_badop(struct vop_generic_args *ap) 236 { 237 return (EIO); 238 } 239 240 241 static int 242 devfs_vop_access(struct vop_access_args *ap) 243 { 244 struct devfs_node *node = DEVFS_NODE(ap->a_vp); 245 int error; 246 247 if (!devfs_node_is_accessible(node)) 248 return ENOENT; 249 node_sync_dev_get(node); 250 error = vop_helper_access(ap, node->uid, node->gid, 251 node->mode, node->flags); 252 253 return error; 254 } 255 256 257 static int 258 devfs_vop_inactive(struct vop_inactive_args *ap) 259 { 260 struct devfs_node *node = DEVFS_NODE(ap->a_vp); 261 262 if (node == NULL || (node->flags & DEVFS_NODE_LINKED) == 0) 263 vrecycle(ap->a_vp); 264 return 0; 265 } 266 267 268 static int 269 devfs_vop_reclaim(struct vop_reclaim_args *ap) 270 { 271 struct devfs_node *node; 272 struct vnode *vp; 273 int locked; 274 275 /* 276 * Check if it is locked already. if not, we acquire the devfs lock 277 */ 278 if (!(lockstatus(&devfs_lock, curthread)) == LK_EXCLUSIVE) { 279 lockmgr(&devfs_lock, LK_EXCLUSIVE); 280 locked = 1; 281 } else { 282 locked = 0; 283 } 284 285 /* 286 * Get rid of the devfs_node if it is no longer linked into the 287 * topology. 288 */ 289 vp = ap->a_vp; 290 if ((node = DEVFS_NODE(vp)) != NULL) { 291 node->v_node = NULL; 292 if ((node->flags & DEVFS_NODE_LINKED) == 0) 293 devfs_freep(node); 294 } 295 296 if (locked) 297 lockmgr(&devfs_lock, LK_RELEASE); 298 299 /* 300 * v_rdev needs to be properly released using v_release_rdev 301 * Make sure v_data is NULL as well. 302 */ 303 vp->v_data = NULL; 304 v_release_rdev(vp); 305 return 0; 306 } 307 308 309 static int 310 devfs_vop_readdir(struct vop_readdir_args *ap) 311 { 312 struct devfs_node *dnode = DEVFS_NODE(ap->a_vp); 313 struct devfs_node *node; 314 int cookie_index; 315 int ncookies; 316 int error2; 317 int error; 318 int r; 319 off_t *cookies; 320 off_t saveoff; 321 322 devfs_debug(DEVFS_DEBUG_DEBUG, "devfs_readdir() called!\n"); 323 324 if (ap->a_uio->uio_offset < 0 || ap->a_uio->uio_offset > INT_MAX) 325 return (EINVAL); 326 if ((error = vn_lock(ap->a_vp, LK_EXCLUSIVE | LK_RETRY)) != 0) 327 return (error); 328 329 if (!devfs_node_is_accessible(dnode)) { 330 vn_unlock(ap->a_vp); 331 return ENOENT; 332 } 333 334 lockmgr(&devfs_lock, LK_EXCLUSIVE); 335 336 saveoff = ap->a_uio->uio_offset; 337 338 if (ap->a_ncookies) { 339 ncookies = ap->a_uio->uio_resid / 16 + 1; /* Why / 16 ?? */ 340 if (ncookies > 256) 341 ncookies = 256; 342 cookies = kmalloc(256 * sizeof(off_t), M_TEMP, M_WAITOK); 343 cookie_index = 0; 344 } else { 345 ncookies = -1; 346 cookies = NULL; 347 cookie_index = 0; 348 } 349 350 nanotime(&dnode->atime); 351 352 if (saveoff == 0) { 353 r = vop_write_dirent(&error, ap->a_uio, dnode->d_dir.d_ino, 354 DT_DIR, 1, "."); 355 if (r) 356 goto done; 357 if (cookies) 358 cookies[cookie_index] = saveoff; 359 saveoff++; 360 cookie_index++; 361 if (cookie_index == ncookies) 362 goto done; 363 } 364 365 if (saveoff == 1) { 366 if (dnode->parent) { 367 r = vop_write_dirent(&error, ap->a_uio, 368 dnode->parent->d_dir.d_ino, 369 DT_DIR, 2, ".."); 370 } else { 371 r = vop_write_dirent(&error, ap->a_uio, 372 dnode->d_dir.d_ino, 373 DT_DIR, 2, ".."); 374 } 375 if (r) 376 goto done; 377 if (cookies) 378 cookies[cookie_index] = saveoff; 379 saveoff++; 380 cookie_index++; 381 if (cookie_index == ncookies) 382 goto done; 383 } 384 385 TAILQ_FOREACH(node, DEVFS_DENODE_HEAD(dnode), link) { 386 if ((node->flags & DEVFS_HIDDEN) || 387 (node->flags & DEVFS_INVISIBLE)) { 388 continue; 389 } 390 391 /* 392 * If the node type is a valid devfs alias, then we make 393 * sure that the target isn't hidden. If it is, we don't 394 * show the link in the directory listing. 395 */ 396 if ((node->node_type == Plink) && (node->link_target != NULL) && 397 (node->link_target->flags & DEVFS_HIDDEN)) 398 continue; 399 400 if (node->cookie < saveoff) 401 continue; 402 403 saveoff = node->cookie; 404 405 error2 = vop_write_dirent(&error, ap->a_uio, node->d_dir.d_ino, 406 node->d_dir.d_type, 407 node->d_dir.d_namlen, 408 node->d_dir.d_name); 409 410 if (error2) 411 break; 412 413 saveoff++; 414 415 if (cookies) 416 cookies[cookie_index] = node->cookie; 417 ++cookie_index; 418 if (cookie_index == ncookies) 419 break; 420 } 421 422 done: 423 lockmgr(&devfs_lock, LK_RELEASE); 424 vn_unlock(ap->a_vp); 425 426 ap->a_uio->uio_offset = saveoff; 427 if (error && cookie_index == 0) { 428 if (cookies) { 429 kfree(cookies, M_TEMP); 430 *ap->a_ncookies = 0; 431 *ap->a_cookies = NULL; 432 } 433 } else { 434 if (cookies) { 435 *ap->a_ncookies = cookie_index; 436 *ap->a_cookies = cookies; 437 } 438 } 439 return (error); 440 } 441 442 443 static int 444 devfs_vop_nresolve(struct vop_nresolve_args *ap) 445 { 446 struct devfs_node *dnode = DEVFS_NODE(ap->a_dvp); 447 struct devfs_node *node, *found = NULL; 448 struct namecache *ncp; 449 struct vnode *vp = NULL; 450 int error = 0; 451 int len; 452 int depth; 453 454 ncp = ap->a_nch->ncp; 455 len = ncp->nc_nlen; 456 457 if (!devfs_node_is_accessible(dnode)) 458 return ENOENT; 459 460 lockmgr(&devfs_lock, LK_EXCLUSIVE); 461 462 if ((dnode->node_type != Proot) && (dnode->node_type != Pdir)) { 463 error = ENOENT; 464 cache_setvp(ap->a_nch, NULL); 465 goto out; 466 } 467 468 TAILQ_FOREACH(node, DEVFS_DENODE_HEAD(dnode), link) { 469 if (len == node->d_dir.d_namlen) { 470 if (!memcmp(ncp->nc_name, node->d_dir.d_name, len)) { 471 found = node; 472 break; 473 } 474 } 475 } 476 477 if (found) { 478 depth = 0; 479 while ((found->node_type == Plink) && (found->link_target)) { 480 if (depth >= 8) { 481 devfs_debug(DEVFS_DEBUG_SHOW, "Recursive link or depth >= 8"); 482 break; 483 } 484 485 found = found->link_target; 486 ++depth; 487 } 488 489 if (!(found->flags & DEVFS_HIDDEN)) 490 devfs_allocv(/*ap->a_dvp->v_mount, */ &vp, found); 491 } 492 493 if (vp == NULL) { 494 error = ENOENT; 495 cache_setvp(ap->a_nch, NULL); 496 goto out; 497 498 } 499 KKASSERT(vp); 500 vn_unlock(vp); 501 cache_setvp(ap->a_nch, vp); 502 vrele(vp); 503 out: 504 lockmgr(&devfs_lock, LK_RELEASE); 505 506 return error; 507 } 508 509 510 static int 511 devfs_vop_nlookupdotdot(struct vop_nlookupdotdot_args *ap) 512 { 513 struct devfs_node *dnode = DEVFS_NODE(ap->a_dvp); 514 515 *ap->a_vpp = NULL; 516 if (!devfs_node_is_accessible(dnode)) 517 return ENOENT; 518 519 lockmgr(&devfs_lock, LK_EXCLUSIVE); 520 if (dnode->parent != NULL) { 521 devfs_allocv(ap->a_vpp, dnode->parent); 522 vn_unlock(*ap->a_vpp); 523 } 524 lockmgr(&devfs_lock, LK_RELEASE); 525 526 return ((*ap->a_vpp == NULL) ? ENOENT : 0); 527 } 528 529 530 static int 531 devfs_vop_getattr(struct vop_getattr_args *ap) 532 { 533 struct devfs_node *node = DEVFS_NODE(ap->a_vp); 534 struct vattr *vap = ap->a_vap; 535 struct partinfo pinfo; 536 int error = 0; 537 538 #if 0 539 if (!devfs_node_is_accessible(node)) 540 return ENOENT; 541 #endif 542 node_sync_dev_get(node); 543 544 lockmgr(&devfs_lock, LK_EXCLUSIVE); 545 546 /* start by zeroing out the attributes */ 547 VATTR_NULL(vap); 548 549 /* next do all the common fields */ 550 vap->va_type = ap->a_vp->v_type; 551 vap->va_mode = node->mode; 552 vap->va_fileid = DEVFS_NODE(ap->a_vp)->d_dir.d_ino ; 553 vap->va_flags = 0; 554 vap->va_blocksize = DEV_BSIZE; 555 vap->va_bytes = vap->va_size = 0; 556 557 vap->va_fsid = ap->a_vp->v_mount->mnt_stat.f_fsid.val[0]; 558 559 vap->va_atime = node->atime; 560 vap->va_mtime = node->mtime; 561 vap->va_ctime = node->ctime; 562 563 vap->va_nlink = 1; /* number of references to file */ 564 565 vap->va_uid = node->uid; 566 vap->va_gid = node->gid; 567 568 vap->va_rmajor = 0; 569 vap->va_rminor = 0; 570 571 if ((node->node_type == Pdev) && node->d_dev) { 572 reference_dev(node->d_dev); 573 vap->va_rminor = node->d_dev->si_uminor; 574 release_dev(node->d_dev); 575 } 576 577 /* For a softlink the va_size is the length of the softlink */ 578 if (node->symlink_name != 0) { 579 vap->va_bytes = vap->va_size = node->symlink_namelen; 580 } 581 582 /* 583 * For a disk-type device, va_size is the size of the underlying 584 * device, so that lseek() works properly. 585 */ 586 if ((node->d_dev) && (dev_dflags(node->d_dev) & D_DISK)) { 587 bzero(&pinfo, sizeof(pinfo)); 588 error = dev_dioctl(node->d_dev, DIOCGPART, (void *)&pinfo, 589 0, proc0.p_ucred, NULL); 590 if ((error == 0) && (pinfo.media_blksize != 0)) { 591 vap->va_size = pinfo.media_size; 592 } else { 593 vap->va_size = 0; 594 error = 0; 595 } 596 } 597 598 lockmgr(&devfs_lock, LK_RELEASE); 599 600 return (error); 601 } 602 603 604 static int 605 devfs_vop_setattr(struct vop_setattr_args *ap) 606 { 607 struct devfs_node *node = DEVFS_NODE(ap->a_vp); 608 struct vattr *vap; 609 int error = 0; 610 611 if (!devfs_node_is_accessible(node)) 612 return ENOENT; 613 node_sync_dev_get(node); 614 615 lockmgr(&devfs_lock, LK_EXCLUSIVE); 616 617 vap = ap->a_vap; 618 619 if (vap->va_uid != (uid_t)VNOVAL) { 620 if ((ap->a_cred->cr_uid != node->uid) && 621 (!groupmember(node->gid, ap->a_cred))) { 622 error = priv_check(curthread, PRIV_VFS_CHOWN); 623 if (error) 624 goto out; 625 } 626 node->uid = vap->va_uid; 627 } 628 629 if (vap->va_gid != (uid_t)VNOVAL) { 630 if ((ap->a_cred->cr_uid != node->uid) && 631 (!groupmember(node->gid, ap->a_cred))) { 632 error = priv_check(curthread, PRIV_VFS_CHOWN); 633 if (error) 634 goto out; 635 } 636 node->gid = vap->va_gid; 637 } 638 639 if (vap->va_mode != (mode_t)VNOVAL) { 640 if (ap->a_cred->cr_uid != node->uid) { 641 error = priv_check(curthread, PRIV_VFS_ADMIN); 642 if (error) 643 goto out; 644 } 645 node->mode = vap->va_mode; 646 } 647 648 out: 649 node_sync_dev_set(node); 650 nanotime(&node->ctime); 651 lockmgr(&devfs_lock, LK_RELEASE); 652 653 return error; 654 } 655 656 657 static int 658 devfs_vop_readlink(struct vop_readlink_args *ap) 659 { 660 struct devfs_node *node = DEVFS_NODE(ap->a_vp); 661 int ret; 662 663 if (!devfs_node_is_accessible(node)) 664 return ENOENT; 665 666 lockmgr(&devfs_lock, LK_EXCLUSIVE); 667 ret = uiomove(node->symlink_name, node->symlink_namelen, ap->a_uio); 668 lockmgr(&devfs_lock, LK_RELEASE); 669 670 return ret; 671 } 672 673 674 static int 675 devfs_vop_print(struct vop_print_args *ap) 676 { 677 return (0); 678 } 679 680 static int 681 devfs_vop_nmkdir(struct vop_nmkdir_args *ap) 682 { 683 struct devfs_node *dnode = DEVFS_NODE(ap->a_dvp); 684 struct devfs_node *node; 685 686 if (!devfs_node_is_accessible(dnode)) 687 return ENOENT; 688 689 if ((dnode->node_type != Proot) && (dnode->node_type != Pdir)) 690 goto out; 691 692 lockmgr(&devfs_lock, LK_EXCLUSIVE); 693 devfs_allocvp(ap->a_dvp->v_mount, ap->a_vpp, Pdir, 694 ap->a_nch->ncp->nc_name, dnode, NULL); 695 696 if (*ap->a_vpp) { 697 node = DEVFS_NODE(*ap->a_vpp); 698 node->flags |= DEVFS_USER_CREATED; 699 cache_setunresolved(ap->a_nch); 700 cache_setvp(ap->a_nch, *ap->a_vpp); 701 } 702 lockmgr(&devfs_lock, LK_RELEASE); 703 out: 704 return ((*ap->a_vpp == NULL) ? ENOTDIR : 0); 705 } 706 707 static int 708 devfs_vop_nsymlink(struct vop_nsymlink_args *ap) 709 { 710 struct devfs_node *dnode = DEVFS_NODE(ap->a_dvp); 711 struct devfs_node *node; 712 size_t targetlen; 713 714 if (!devfs_node_is_accessible(dnode)) 715 return ENOENT; 716 717 ap->a_vap->va_type = VLNK; 718 719 if ((dnode->node_type != Proot) && (dnode->node_type != Pdir)) 720 goto out; 721 722 lockmgr(&devfs_lock, LK_EXCLUSIVE); 723 devfs_allocvp(ap->a_dvp->v_mount, ap->a_vpp, Plink, 724 ap->a_nch->ncp->nc_name, dnode, NULL); 725 726 targetlen = strlen(ap->a_target); 727 if (*ap->a_vpp) { 728 node = DEVFS_NODE(*ap->a_vpp); 729 node->flags |= DEVFS_USER_CREATED; 730 node->symlink_namelen = targetlen; 731 node->symlink_name = kmalloc(targetlen + 1, M_DEVFS, M_WAITOK); 732 memcpy(node->symlink_name, ap->a_target, targetlen); 733 node->symlink_name[targetlen] = '\0'; 734 cache_setunresolved(ap->a_nch); 735 cache_setvp(ap->a_nch, *ap->a_vpp); 736 } 737 lockmgr(&devfs_lock, LK_RELEASE); 738 out: 739 return ((*ap->a_vpp == NULL) ? ENOTDIR : 0); 740 } 741 742 static int 743 devfs_vop_nrmdir(struct vop_nrmdir_args *ap) 744 { 745 struct devfs_node *dnode = DEVFS_NODE(ap->a_dvp); 746 struct devfs_node *node; 747 struct namecache *ncp; 748 int error = ENOENT; 749 750 ncp = ap->a_nch->ncp; 751 752 if (!devfs_node_is_accessible(dnode)) 753 return ENOENT; 754 755 lockmgr(&devfs_lock, LK_EXCLUSIVE); 756 757 if ((dnode->node_type != Proot) && (dnode->node_type != Pdir)) 758 goto out; 759 760 TAILQ_FOREACH(node, DEVFS_DENODE_HEAD(dnode), link) { 761 if (ncp->nc_nlen != node->d_dir.d_namlen) 762 continue; 763 if (memcmp(ncp->nc_name, node->d_dir.d_name, ncp->nc_nlen)) 764 continue; 765 766 /* 767 * only allow removal of user created dirs 768 */ 769 if ((node->flags & DEVFS_USER_CREATED) == 0) { 770 error = EPERM; 771 goto out; 772 } else if (node->node_type != Pdir) { 773 error = ENOTDIR; 774 goto out; 775 } else if (node->nchildren > 2) { 776 error = ENOTEMPTY; 777 goto out; 778 } else { 779 if (node->v_node) 780 cache_inval_vp(node->v_node, CINV_DESTROY); 781 devfs_unlinkp(node); 782 error = 0; 783 break; 784 } 785 } 786 787 cache_setunresolved(ap->a_nch); 788 cache_setvp(ap->a_nch, NULL); 789 790 out: 791 lockmgr(&devfs_lock, LK_RELEASE); 792 return error; 793 } 794 795 static int 796 devfs_vop_nremove(struct vop_nremove_args *ap) 797 { 798 struct devfs_node *dnode = DEVFS_NODE(ap->a_dvp); 799 struct devfs_node *node; 800 struct namecache *ncp; 801 int error = ENOENT; 802 803 ncp = ap->a_nch->ncp; 804 805 if (!devfs_node_is_accessible(dnode)) 806 return ENOENT; 807 808 lockmgr(&devfs_lock, LK_EXCLUSIVE); 809 810 if ((dnode->node_type != Proot) && (dnode->node_type != Pdir)) 811 goto out; 812 813 TAILQ_FOREACH(node, DEVFS_DENODE_HEAD(dnode), link) { 814 if (ncp->nc_nlen != node->d_dir.d_namlen) 815 continue; 816 if (memcmp(ncp->nc_name, node->d_dir.d_name, ncp->nc_nlen)) 817 continue; 818 819 /* 820 * only allow removal of user created stuff (e.g. symlinks) 821 */ 822 if ((node->flags & DEVFS_USER_CREATED) == 0) { 823 error = EPERM; 824 goto out; 825 } else if (node->node_type == Pdir) { 826 error = EISDIR; 827 goto out; 828 } else { 829 if (node->v_node) 830 cache_inval_vp(node->v_node, CINV_DESTROY); 831 devfs_unlinkp(node); 832 error = 0; 833 break; 834 } 835 } 836 837 cache_setunresolved(ap->a_nch); 838 cache_setvp(ap->a_nch, NULL); 839 840 out: 841 lockmgr(&devfs_lock, LK_RELEASE); 842 return error; 843 } 844 845 846 static int 847 devfs_spec_open(struct vop_open_args *ap) 848 { 849 struct vnode *vp = ap->a_vp; 850 struct vnode *orig_vp = NULL; 851 struct devfs_node *node = DEVFS_NODE(vp); 852 struct devfs_node *newnode; 853 cdev_t dev, ndev = NULL; 854 int error = 0; 855 856 if (node) { 857 if (node->d_dev == NULL) 858 return ENXIO; 859 if (!devfs_node_is_accessible(node)) 860 return ENOENT; 861 } 862 863 if ((dev = vp->v_rdev) == NULL) 864 return ENXIO; 865 866 if (node && ap->a_fp) { 867 devfs_debug(DEVFS_DEBUG_DEBUG, "devfs_spec_open: -1.1-\n"); 868 lockmgr(&devfs_lock, LK_EXCLUSIVE); 869 870 ndev = devfs_clone(dev, node->d_dir.d_name, node->d_dir.d_namlen, 871 ap->a_mode, ap->a_cred); 872 if (ndev != NULL) { 873 newnode = devfs_create_device_node( 874 DEVFS_MNTDATA(vp->v_mount)->root_node, 875 ndev, NULL, NULL); 876 /* XXX: possibly destroy device if this happens */ 877 878 if (newnode != NULL) { 879 dev = ndev; 880 devfs_link_dev(dev); 881 882 devfs_debug(DEVFS_DEBUG_DEBUG, 883 "parent here is: %s, node is: |%s|\n", 884 ((node->parent->node_type == Proot) ? 885 "ROOT!" : node->parent->d_dir.d_name), 886 newnode->d_dir.d_name); 887 devfs_debug(DEVFS_DEBUG_DEBUG, 888 "test: %s\n", 889 ((struct devfs_node *)(TAILQ_LAST(DEVFS_DENODE_HEAD(node->parent), devfs_node_head)))->d_dir.d_name); 890 891 /* 892 * orig_vp is set to the original vp if we cloned. 893 */ 894 /* node->flags |= DEVFS_CLONED; */ 895 devfs_allocv(&vp, newnode); 896 orig_vp = ap->a_vp; 897 ap->a_vp = vp; 898 } 899 } 900 lockmgr(&devfs_lock, LK_RELEASE); 901 } 902 903 devfs_debug(DEVFS_DEBUG_DEBUG, 904 "devfs_spec_open() called on %s! \n", 905 dev->si_name); 906 907 /* 908 * Make this field valid before any I/O in ->d_open 909 */ 910 if (!dev->si_iosize_max) 911 dev->si_iosize_max = DFLTPHYS; 912 913 if (dev_dflags(dev) & D_TTY) 914 vsetflags(vp, VISTTY); 915 916 /* 917 * Open underlying device 918 */ 919 vn_unlock(vp); 920 error = dev_dopen(dev, ap->a_mode, S_IFCHR, ap->a_cred); 921 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 922 923 /* 924 * Clean up any cloned vp if we error out. 925 */ 926 if (error) { 927 if (orig_vp) { 928 vput(vp); 929 ap->a_vp = orig_vp; 930 /* orig_vp = NULL; */ 931 } 932 return error; 933 } 934 935 /* 936 * This checks if the disk device is going to be opened for writing. 937 * It will be only allowed in the cases where securelevel permits it 938 * and it's not mounted R/W. 939 */ 940 if ((dev_dflags(dev) & D_DISK) && (ap->a_mode & FWRITE) && 941 (ap->a_cred != FSCRED)) { 942 943 /* Very secure mode. No open for writing allowed */ 944 if (securelevel >= 2) 945 return EPERM; 946 947 /* 948 * If it is mounted R/W, do not allow to open for writing. 949 * In the case it's mounted read-only but securelevel 950 * is >= 1, then do not allow opening for writing either. 951 */ 952 if (vfs_mountedon(vp)) { 953 if (!(dev->si_mountpoint->mnt_flag & MNT_RDONLY)) 954 return EBUSY; 955 else if (securelevel >= 1) 956 return EPERM; 957 } 958 } 959 960 if (dev_dflags(dev) & D_TTY) { 961 if (dev->si_tty) { 962 struct tty *tp; 963 tp = dev->si_tty; 964 if (!tp->t_stop) { 965 devfs_debug(DEVFS_DEBUG_DEBUG, 966 "devfs: no t_stop\n"); 967 tp->t_stop = nottystop; 968 } 969 } 970 } 971 972 973 if (vn_isdisk(vp, NULL)) { 974 if (!dev->si_bsize_phys) 975 dev->si_bsize_phys = DEV_BSIZE; 976 vinitvmio(vp, IDX_TO_OFF(INT_MAX), PAGE_SIZE, -1); 977 } 978 979 vop_stdopen(ap); 980 #if 0 981 if (node) 982 nanotime(&node->atime); 983 #endif 984 985 /* 986 * If we replaced the vp the vop_stdopen() call will have loaded 987 * it into fp->f_data and vref()d the vp, giving us two refs. So 988 * instead of just unlocking it here we have to vput() it. 989 */ 990 if (orig_vp) 991 vput(vp); 992 993 /* Ugly pty magic, to make pty devices appear once they are opened */ 994 if (node && (node->flags & DEVFS_PTY) == DEVFS_PTY) 995 node->flags &= ~DEVFS_INVISIBLE; 996 997 if (ap->a_fp) { 998 KKASSERT(ap->a_fp->f_type == DTYPE_VNODE); 999 KKASSERT(ap->a_fp->f_flag == (ap->a_mode & FMASK)); 1000 ap->a_fp->f_ops = &devfs_dev_fileops; 1001 KKASSERT(ap->a_fp->f_data == (void *)vp); 1002 } 1003 1004 return 0; 1005 } 1006 1007 1008 static int 1009 devfs_spec_close(struct vop_close_args *ap) 1010 { 1011 struct devfs_node *node = DEVFS_NODE(ap->a_vp); 1012 struct proc *p = curproc; 1013 struct vnode *vp = ap->a_vp; 1014 cdev_t dev = vp->v_rdev; 1015 int error = 0; 1016 int needrelock; 1017 1018 devfs_debug(DEVFS_DEBUG_DEBUG, 1019 "devfs_spec_close() called on %s! \n", 1020 dev->si_name); 1021 1022 /* 1023 * A couple of hacks for devices and tty devices. The 1024 * vnode ref count cannot be used to figure out the 1025 * last close, but we can use v_opencount now that 1026 * revoke works properly. 1027 * 1028 * Detect the last close on a controlling terminal and clear 1029 * the session (half-close). 1030 */ 1031 if (dev) 1032 reference_dev(dev); 1033 1034 if (p && vp->v_opencount <= 1 && vp == p->p_session->s_ttyvp) { 1035 p->p_session->s_ttyvp = NULL; 1036 vrele(vp); 1037 } 1038 1039 /* 1040 * Vnodes can be opened and closed multiple times. Do not really 1041 * close the device unless (1) it is being closed forcibly, 1042 * (2) the device wants to track closes, or (3) this is the last 1043 * vnode doing its last close on the device. 1044 * 1045 * XXX the VXLOCK (force close) case can leave vnodes referencing 1046 * a closed device. This might not occur now that our revoke is 1047 * fixed. 1048 */ 1049 devfs_debug(DEVFS_DEBUG_DEBUG, "devfs_spec_close() -1- \n"); 1050 if (dev && ((vp->v_flag & VRECLAIMED) || 1051 (dev_dflags(dev) & D_TRACKCLOSE) || 1052 (vp->v_opencount == 1))) { 1053 /* 1054 * Unlock around dev_dclose() 1055 */ 1056 needrelock = 0; 1057 if (vn_islocked(vp)) { 1058 needrelock = 1; 1059 vn_unlock(vp); 1060 } 1061 error = dev_dclose(dev, ap->a_fflag, S_IFCHR); 1062 1063 /* 1064 * Ugly pty magic, to make pty devices disappear again once 1065 * they are closed 1066 */ 1067 if (node && (node->flags & DEVFS_PTY) == DEVFS_PTY) 1068 node->flags |= DEVFS_INVISIBLE; 1069 1070 if (needrelock) 1071 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 1072 } else { 1073 error = 0; 1074 } 1075 devfs_debug(DEVFS_DEBUG_DEBUG, "devfs_spec_close() -2- \n"); 1076 1077 /* 1078 * Track the actual opens and closes on the vnode. The last close 1079 * disassociates the rdev. If the rdev is already disassociated or 1080 * the opencount is already 0, the vnode might have been revoked 1081 * and no further opencount tracking occurs. 1082 */ 1083 if (dev) 1084 release_dev(dev); 1085 if (vp->v_opencount > 0) 1086 vop_stdclose(ap); 1087 return(error); 1088 1089 } 1090 1091 1092 static int 1093 devfs_fo_close(struct file *fp) 1094 { 1095 struct vnode *vp = (struct vnode *)fp->f_data; 1096 int error; 1097 1098 fp->f_ops = &badfileops; 1099 error = vn_close(vp, fp->f_flag); 1100 1101 return (error); 1102 } 1103 1104 1105 /* 1106 * Device-optimized file table vnode read routine. 1107 * 1108 * This bypasses the VOP table and talks directly to the device. Most 1109 * filesystems just route to specfs and can make this optimization. 1110 * 1111 * MPALMOSTSAFE - acquires mplock 1112 */ 1113 static int 1114 devfs_fo_read(struct file *fp, struct uio *uio, 1115 struct ucred *cred, int flags) 1116 { 1117 struct devfs_node *node; 1118 struct vnode *vp; 1119 int ioflag; 1120 int error; 1121 cdev_t dev; 1122 1123 KASSERT(uio->uio_td == curthread, 1124 ("uio_td %p is not td %p", uio->uio_td, curthread)); 1125 1126 if (uio->uio_resid == 0) 1127 return 0; 1128 1129 vp = (struct vnode *)fp->f_data; 1130 if (vp == NULL || vp->v_type == VBAD) 1131 return EBADF; 1132 1133 node = DEVFS_NODE(vp); 1134 1135 if ((dev = vp->v_rdev) == NULL) 1136 return EBADF; 1137 1138 reference_dev(dev); 1139 1140 if ((flags & O_FOFFSET) == 0) 1141 uio->uio_offset = fp->f_offset; 1142 1143 ioflag = 0; 1144 if (flags & O_FBLOCKING) { 1145 /* ioflag &= ~IO_NDELAY; */ 1146 } else if (flags & O_FNONBLOCKING) { 1147 ioflag |= IO_NDELAY; 1148 } else if (fp->f_flag & FNONBLOCK) { 1149 ioflag |= IO_NDELAY; 1150 } 1151 if (flags & O_FBUFFERED) { 1152 /* ioflag &= ~IO_DIRECT; */ 1153 } else if (flags & O_FUNBUFFERED) { 1154 ioflag |= IO_DIRECT; 1155 } else if (fp->f_flag & O_DIRECT) { 1156 ioflag |= IO_DIRECT; 1157 } 1158 ioflag |= sequential_heuristic(uio, fp); 1159 1160 error = dev_dread(dev, uio, ioflag); 1161 1162 release_dev(dev); 1163 if (node) 1164 nanotime(&node->atime); 1165 if ((flags & O_FOFFSET) == 0) 1166 fp->f_offset = uio->uio_offset; 1167 fp->f_nextoff = uio->uio_offset; 1168 1169 return (error); 1170 } 1171 1172 1173 static int 1174 devfs_fo_write(struct file *fp, struct uio *uio, 1175 struct ucred *cred, int flags) 1176 { 1177 struct devfs_node *node; 1178 struct vnode *vp; 1179 int ioflag; 1180 int error; 1181 cdev_t dev; 1182 1183 KASSERT(uio->uio_td == curthread, 1184 ("uio_td %p is not p %p", uio->uio_td, curthread)); 1185 1186 vp = (struct vnode *)fp->f_data; 1187 if (vp == NULL || vp->v_type == VBAD) 1188 return EBADF; 1189 1190 node = DEVFS_NODE(vp); 1191 1192 if (vp->v_type == VREG) 1193 bwillwrite(uio->uio_resid); 1194 1195 vp = (struct vnode *)fp->f_data; 1196 1197 if ((dev = vp->v_rdev) == NULL) 1198 return EBADF; 1199 1200 reference_dev(dev); 1201 1202 if ((flags & O_FOFFSET) == 0) 1203 uio->uio_offset = fp->f_offset; 1204 1205 ioflag = IO_UNIT; 1206 if (vp->v_type == VREG && 1207 ((fp->f_flag & O_APPEND) || (flags & O_FAPPEND))) { 1208 ioflag |= IO_APPEND; 1209 } 1210 1211 if (flags & O_FBLOCKING) { 1212 /* ioflag &= ~IO_NDELAY; */ 1213 } else if (flags & O_FNONBLOCKING) { 1214 ioflag |= IO_NDELAY; 1215 } else if (fp->f_flag & FNONBLOCK) { 1216 ioflag |= IO_NDELAY; 1217 } 1218 if (flags & O_FBUFFERED) { 1219 /* ioflag &= ~IO_DIRECT; */ 1220 } else if (flags & O_FUNBUFFERED) { 1221 ioflag |= IO_DIRECT; 1222 } else if (fp->f_flag & O_DIRECT) { 1223 ioflag |= IO_DIRECT; 1224 } 1225 if (flags & O_FASYNCWRITE) { 1226 /* ioflag &= ~IO_SYNC; */ 1227 } else if (flags & O_FSYNCWRITE) { 1228 ioflag |= IO_SYNC; 1229 } else if (fp->f_flag & O_FSYNC) { 1230 ioflag |= IO_SYNC; 1231 } 1232 1233 if (vp->v_mount && (vp->v_mount->mnt_flag & MNT_SYNCHRONOUS)) 1234 ioflag |= IO_SYNC; 1235 ioflag |= sequential_heuristic(uio, fp); 1236 1237 error = dev_dwrite(dev, uio, ioflag); 1238 1239 release_dev(dev); 1240 if (node) { 1241 nanotime(&node->atime); 1242 nanotime(&node->mtime); 1243 } 1244 1245 if ((flags & O_FOFFSET) == 0) 1246 fp->f_offset = uio->uio_offset; 1247 fp->f_nextoff = uio->uio_offset; 1248 1249 return (error); 1250 } 1251 1252 1253 static int 1254 devfs_fo_stat(struct file *fp, struct stat *sb, struct ucred *cred) 1255 { 1256 struct vnode *vp; 1257 struct vattr vattr; 1258 struct vattr *vap; 1259 u_short mode; 1260 cdev_t dev; 1261 int error; 1262 1263 vp = (struct vnode *)fp->f_data; 1264 if (vp == NULL || vp->v_type == VBAD) 1265 return EBADF; 1266 1267 error = vn_stat(vp, sb, cred); 1268 if (error) 1269 return (error); 1270 1271 vap = &vattr; 1272 error = VOP_GETATTR(vp, vap); 1273 if (error) 1274 return (error); 1275 1276 /* 1277 * Zero the spare stat fields 1278 */ 1279 sb->st_lspare = 0; 1280 sb->st_qspare1 = 0; 1281 sb->st_qspare2 = 0; 1282 1283 /* 1284 * Copy from vattr table ... or not in case it's a cloned device 1285 */ 1286 if (vap->va_fsid != VNOVAL) 1287 sb->st_dev = vap->va_fsid; 1288 else 1289 sb->st_dev = vp->v_mount->mnt_stat.f_fsid.val[0]; 1290 1291 sb->st_ino = vap->va_fileid; 1292 1293 mode = vap->va_mode; 1294 mode |= S_IFCHR; 1295 sb->st_mode = mode; 1296 1297 if (vap->va_nlink > (nlink_t)-1) 1298 sb->st_nlink = (nlink_t)-1; 1299 else 1300 sb->st_nlink = vap->va_nlink; 1301 1302 sb->st_uid = vap->va_uid; 1303 sb->st_gid = vap->va_gid; 1304 sb->st_rdev = dev2udev(DEVFS_NODE(vp)->d_dev); 1305 sb->st_size = vap->va_bytes; 1306 sb->st_atimespec = vap->va_atime; 1307 sb->st_mtimespec = vap->va_mtime; 1308 sb->st_ctimespec = vap->va_ctime; 1309 1310 /* 1311 * A VCHR and VBLK device may track the last access and last modified 1312 * time independantly of the filesystem. This is particularly true 1313 * because device read and write calls may bypass the filesystem. 1314 */ 1315 if (vp->v_type == VCHR || vp->v_type == VBLK) { 1316 dev = vp->v_rdev; 1317 if (dev != NULL) { 1318 if (dev->si_lastread) { 1319 sb->st_atimespec.tv_sec = dev->si_lastread; 1320 sb->st_atimespec.tv_nsec = 0; 1321 } 1322 if (dev->si_lastwrite) { 1323 sb->st_atimespec.tv_sec = dev->si_lastwrite; 1324 sb->st_atimespec.tv_nsec = 0; 1325 } 1326 } 1327 } 1328 1329 /* 1330 * According to www.opengroup.org, the meaning of st_blksize is 1331 * "a filesystem-specific preferred I/O block size for this 1332 * object. In some filesystem types, this may vary from file 1333 * to file" 1334 * Default to PAGE_SIZE after much discussion. 1335 */ 1336 1337 sb->st_blksize = PAGE_SIZE; 1338 1339 sb->st_flags = vap->va_flags; 1340 1341 error = priv_check_cred(cred, PRIV_VFS_GENERATION, 0); 1342 if (error) 1343 sb->st_gen = 0; 1344 else 1345 sb->st_gen = (u_int32_t)vap->va_gen; 1346 1347 sb->st_blocks = vap->va_bytes / S_BLKSIZE; 1348 1349 return (0); 1350 } 1351 1352 1353 static int 1354 devfs_fo_kqfilter(struct file *fp, struct knote *kn) 1355 { 1356 struct vnode *vp; 1357 int error; 1358 cdev_t dev; 1359 1360 vp = (struct vnode *)fp->f_data; 1361 if (vp == NULL || vp->v_type == VBAD) { 1362 error = EBADF; 1363 goto done; 1364 } 1365 if ((dev = vp->v_rdev) == NULL) { 1366 error = EBADF; 1367 goto done; 1368 } 1369 reference_dev(dev); 1370 1371 error = dev_dkqfilter(dev, kn); 1372 1373 release_dev(dev); 1374 1375 done: 1376 return (error); 1377 } 1378 1379 /* 1380 * MPALMOSTSAFE - acquires mplock 1381 */ 1382 static int 1383 devfs_fo_ioctl(struct file *fp, u_long com, caddr_t data, 1384 struct ucred *ucred, struct sysmsg *msg) 1385 { 1386 struct devfs_node *node; 1387 struct vnode *vp; 1388 struct vnode *ovp; 1389 cdev_t dev; 1390 int error; 1391 struct fiodname_args *name_args; 1392 size_t namlen; 1393 const char *name; 1394 1395 vp = ((struct vnode *)fp->f_data); 1396 1397 if ((dev = vp->v_rdev) == NULL) 1398 return EBADF; /* device was revoked */ 1399 1400 reference_dev(dev); 1401 1402 node = DEVFS_NODE(vp); 1403 1404 devfs_debug(DEVFS_DEBUG_DEBUG, 1405 "devfs_fo_ioctl() called! for dev %s\n", 1406 dev->si_name); 1407 1408 if (com == FIODTYPE) { 1409 *(int *)data = dev_dflags(dev) & D_TYPEMASK; 1410 error = 0; 1411 goto out; 1412 } else if (com == FIODNAME) { 1413 name_args = (struct fiodname_args *)data; 1414 name = dev->si_name; 1415 namlen = strlen(name) + 1; 1416 1417 devfs_debug(DEVFS_DEBUG_DEBUG, 1418 "ioctl, got: FIODNAME for %s\n", name); 1419 1420 if (namlen <= name_args->len) 1421 error = copyout(dev->si_name, name_args->name, namlen); 1422 else 1423 error = EINVAL; 1424 1425 devfs_debug(DEVFS_DEBUG_DEBUG, 1426 "ioctl stuff: error: %d\n", error); 1427 goto out; 1428 } 1429 1430 error = dev_dioctl(dev, com, data, fp->f_flag, ucred, msg); 1431 1432 #if 0 1433 if (node) { 1434 nanotime(&node->atime); 1435 nanotime(&node->mtime); 1436 } 1437 #endif 1438 if (com == TIOCSCTTY) { 1439 devfs_debug(DEVFS_DEBUG_DEBUG, 1440 "devfs_fo_ioctl: got TIOCSCTTY on %s\n", 1441 dev->si_name); 1442 } 1443 if (error == 0 && com == TIOCSCTTY) { 1444 struct proc *p = curthread->td_proc; 1445 struct session *sess; 1446 1447 devfs_debug(DEVFS_DEBUG_DEBUG, 1448 "devfs_fo_ioctl: dealing with TIOCSCTTY on %s\n", 1449 dev->si_name); 1450 if (p == NULL) { 1451 error = ENOTTY; 1452 goto out; 1453 } 1454 sess = p->p_session; 1455 1456 /* 1457 * Do nothing if reassigning same control tty 1458 */ 1459 if (sess->s_ttyvp == vp) { 1460 error = 0; 1461 goto out; 1462 } 1463 1464 /* 1465 * Get rid of reference to old control tty 1466 */ 1467 ovp = sess->s_ttyvp; 1468 vref(vp); 1469 sess->s_ttyvp = vp; 1470 if (ovp) 1471 vrele(ovp); 1472 } 1473 1474 out: 1475 release_dev(dev); 1476 devfs_debug(DEVFS_DEBUG_DEBUG, "devfs_fo_ioctl() finished! \n"); 1477 return (error); 1478 } 1479 1480 1481 static int 1482 devfs_spec_fsync(struct vop_fsync_args *ap) 1483 { 1484 struct vnode *vp = ap->a_vp; 1485 int error; 1486 1487 if (!vn_isdisk(vp, NULL)) 1488 return (0); 1489 1490 /* 1491 * Flush all dirty buffers associated with a block device. 1492 */ 1493 error = vfsync(vp, ap->a_waitfor, 10000, NULL, NULL); 1494 return (error); 1495 } 1496 1497 static int 1498 devfs_spec_read(struct vop_read_args *ap) 1499 { 1500 struct devfs_node *node; 1501 struct vnode *vp; 1502 struct uio *uio; 1503 cdev_t dev; 1504 int error; 1505 1506 vp = ap->a_vp; 1507 dev = vp->v_rdev; 1508 uio = ap->a_uio; 1509 node = DEVFS_NODE(vp); 1510 1511 if (dev == NULL) /* device was revoked */ 1512 return (EBADF); 1513 if (uio->uio_resid == 0) 1514 return (0); 1515 1516 vn_unlock(vp); 1517 error = dev_dread(dev, uio, ap->a_ioflag); 1518 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 1519 1520 if (node) 1521 nanotime(&node->atime); 1522 1523 return (error); 1524 } 1525 1526 /* 1527 * Vnode op for write 1528 * 1529 * spec_write(struct vnode *a_vp, struct uio *a_uio, int a_ioflag, 1530 * struct ucred *a_cred) 1531 */ 1532 static int 1533 devfs_spec_write(struct vop_write_args *ap) 1534 { 1535 struct devfs_node *node; 1536 struct vnode *vp; 1537 struct uio *uio; 1538 cdev_t dev; 1539 int error; 1540 1541 vp = ap->a_vp; 1542 dev = vp->v_rdev; 1543 uio = ap->a_uio; 1544 node = DEVFS_NODE(vp); 1545 1546 KKASSERT(uio->uio_segflg != UIO_NOCOPY); 1547 1548 if (dev == NULL) /* device was revoked */ 1549 return (EBADF); 1550 1551 vn_unlock(vp); 1552 error = dev_dwrite(dev, uio, ap->a_ioflag); 1553 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 1554 1555 if (node) { 1556 nanotime(&node->atime); 1557 nanotime(&node->mtime); 1558 } 1559 1560 return (error); 1561 } 1562 1563 /* 1564 * Device ioctl operation. 1565 * 1566 * spec_ioctl(struct vnode *a_vp, int a_command, caddr_t a_data, 1567 * int a_fflag, struct ucred *a_cred, struct sysmsg *msg) 1568 */ 1569 static int 1570 devfs_spec_ioctl(struct vop_ioctl_args *ap) 1571 { 1572 struct vnode *vp = ap->a_vp; 1573 struct devfs_node *node; 1574 cdev_t dev; 1575 1576 if ((dev = vp->v_rdev) == NULL) 1577 return (EBADF); /* device was revoked */ 1578 node = DEVFS_NODE(vp); 1579 1580 #if 0 1581 if (node) { 1582 nanotime(&node->atime); 1583 nanotime(&node->mtime); 1584 } 1585 #endif 1586 1587 return (dev_dioctl(dev, ap->a_command, ap->a_data, ap->a_fflag, 1588 ap->a_cred, ap->a_sysmsg)); 1589 } 1590 1591 /* 1592 * spec_kqfilter(struct vnode *a_vp, struct knote *a_kn) 1593 */ 1594 /* ARGSUSED */ 1595 static int 1596 devfs_spec_kqfilter(struct vop_kqfilter_args *ap) 1597 { 1598 struct vnode *vp = ap->a_vp; 1599 struct devfs_node *node; 1600 cdev_t dev; 1601 1602 if ((dev = vp->v_rdev) == NULL) 1603 return (EBADF); /* device was revoked (EBADF) */ 1604 node = DEVFS_NODE(vp); 1605 1606 #if 0 1607 if (node) 1608 nanotime(&node->atime); 1609 #endif 1610 1611 return (dev_dkqfilter(dev, ap->a_kn)); 1612 } 1613 1614 /* 1615 * Convert a vnode strategy call into a device strategy call. Vnode strategy 1616 * calls are not limited to device DMA limits so we have to deal with the 1617 * case. 1618 * 1619 * spec_strategy(struct vnode *a_vp, struct bio *a_bio) 1620 */ 1621 static int 1622 devfs_spec_strategy(struct vop_strategy_args *ap) 1623 { 1624 struct bio *bio = ap->a_bio; 1625 struct buf *bp = bio->bio_buf; 1626 struct buf *nbp; 1627 struct vnode *vp; 1628 struct mount *mp; 1629 int chunksize; 1630 int maxiosize; 1631 1632 if (bp->b_cmd != BUF_CMD_READ && LIST_FIRST(&bp->b_dep) != NULL) 1633 buf_start(bp); 1634 1635 /* 1636 * Collect statistics on synchronous and asynchronous read 1637 * and write counts for disks that have associated filesystems. 1638 */ 1639 vp = ap->a_vp; 1640 KKASSERT(vp->v_rdev != NULL); /* XXX */ 1641 if (vn_isdisk(vp, NULL) && (mp = vp->v_rdev->si_mountpoint) != NULL) { 1642 if (bp->b_cmd == BUF_CMD_READ) { 1643 if (bp->b_flags & BIO_SYNC) 1644 mp->mnt_stat.f_syncreads++; 1645 else 1646 mp->mnt_stat.f_asyncreads++; 1647 } else { 1648 if (bp->b_flags & BIO_SYNC) 1649 mp->mnt_stat.f_syncwrites++; 1650 else 1651 mp->mnt_stat.f_asyncwrites++; 1652 } 1653 } 1654 1655 /* 1656 * Device iosize limitations only apply to read and write. Shortcut 1657 * the I/O if it fits. 1658 */ 1659 if ((maxiosize = vp->v_rdev->si_iosize_max) == 0) { 1660 devfs_debug(DEVFS_DEBUG_DEBUG, 1661 "%s: si_iosize_max not set!\n", 1662 dev_dname(vp->v_rdev)); 1663 maxiosize = MAXPHYS; 1664 } 1665 #if SPEC_CHAIN_DEBUG & 2 1666 maxiosize = 4096; 1667 #endif 1668 if (bp->b_bcount <= maxiosize || 1669 (bp->b_cmd != BUF_CMD_READ && bp->b_cmd != BUF_CMD_WRITE)) { 1670 dev_dstrategy_chain(vp->v_rdev, bio); 1671 return (0); 1672 } 1673 1674 /* 1675 * Clone the buffer and set up an I/O chain to chunk up the I/O. 1676 */ 1677 nbp = kmalloc(sizeof(*bp), M_DEVBUF, M_INTWAIT|M_ZERO); 1678 initbufbio(nbp); 1679 buf_dep_init(nbp); 1680 BUF_LOCKINIT(nbp); 1681 BUF_LOCK(nbp, LK_EXCLUSIVE); 1682 BUF_KERNPROC(nbp); 1683 nbp->b_vp = vp; 1684 nbp->b_flags = B_PAGING | (bp->b_flags & B_BNOCLIP); 1685 nbp->b_data = bp->b_data; 1686 nbp->b_bio1.bio_done = devfs_spec_strategy_done; 1687 nbp->b_bio1.bio_offset = bio->bio_offset; 1688 nbp->b_bio1.bio_caller_info1.ptr = bio; 1689 1690 /* 1691 * Start the first transfer 1692 */ 1693 if (vn_isdisk(vp, NULL)) 1694 chunksize = vp->v_rdev->si_bsize_phys; 1695 else 1696 chunksize = DEV_BSIZE; 1697 chunksize = maxiosize / chunksize * chunksize; 1698 #if SPEC_CHAIN_DEBUG & 1 1699 devfs_debug(DEVFS_DEBUG_DEBUG, 1700 "spec_strategy chained I/O chunksize=%d\n", 1701 chunksize); 1702 #endif 1703 nbp->b_cmd = bp->b_cmd; 1704 nbp->b_bcount = chunksize; 1705 nbp->b_bufsize = chunksize; /* used to detect a short I/O */ 1706 nbp->b_bio1.bio_caller_info2.index = chunksize; 1707 1708 #if SPEC_CHAIN_DEBUG & 1 1709 devfs_debug(DEVFS_DEBUG_DEBUG, 1710 "spec_strategy: chain %p offset %d/%d bcount %d\n", 1711 bp, 0, bp->b_bcount, nbp->b_bcount); 1712 #endif 1713 1714 dev_dstrategy(vp->v_rdev, &nbp->b_bio1); 1715 1716 if (DEVFS_NODE(vp)) { 1717 nanotime(&DEVFS_NODE(vp)->atime); 1718 nanotime(&DEVFS_NODE(vp)->mtime); 1719 } 1720 1721 return (0); 1722 } 1723 1724 /* 1725 * Chunked up transfer completion routine - chain transfers until done 1726 */ 1727 static 1728 void 1729 devfs_spec_strategy_done(struct bio *nbio) 1730 { 1731 struct buf *nbp = nbio->bio_buf; 1732 struct bio *bio = nbio->bio_caller_info1.ptr; /* original bio */ 1733 struct buf *bp = bio->bio_buf; /* original bp */ 1734 int chunksize = nbio->bio_caller_info2.index; /* chunking */ 1735 int boffset = nbp->b_data - bp->b_data; 1736 1737 if (nbp->b_flags & B_ERROR) { 1738 /* 1739 * An error terminates the chain, propogate the error back 1740 * to the original bp 1741 */ 1742 bp->b_flags |= B_ERROR; 1743 bp->b_error = nbp->b_error; 1744 bp->b_resid = bp->b_bcount - boffset + 1745 (nbp->b_bcount - nbp->b_resid); 1746 #if SPEC_CHAIN_DEBUG & 1 1747 devfs_debug(DEVFS_DEBUG_DEBUG, 1748 "spec_strategy: chain %p error %d bcount %d/%d\n", 1749 bp, bp->b_error, bp->b_bcount, 1750 bp->b_bcount - bp->b_resid); 1751 #endif 1752 kfree(nbp, M_DEVBUF); 1753 biodone(bio); 1754 } else if (nbp->b_resid) { 1755 /* 1756 * A short read or write terminates the chain 1757 */ 1758 bp->b_error = nbp->b_error; 1759 bp->b_resid = bp->b_bcount - boffset + 1760 (nbp->b_bcount - nbp->b_resid); 1761 #if SPEC_CHAIN_DEBUG & 1 1762 devfs_debug(DEVFS_DEBUG_DEBUG, 1763 "spec_strategy: chain %p short read(1) " 1764 "bcount %d/%d\n", 1765 bp, bp->b_bcount - bp->b_resid, bp->b_bcount); 1766 #endif 1767 kfree(nbp, M_DEVBUF); 1768 biodone(bio); 1769 } else if (nbp->b_bcount != nbp->b_bufsize) { 1770 /* 1771 * A short read or write can also occur by truncating b_bcount 1772 */ 1773 #if SPEC_CHAIN_DEBUG & 1 1774 devfs_debug(DEVFS_DEBUG_DEBUG, 1775 "spec_strategy: chain %p short read(2) " 1776 "bcount %d/%d\n", 1777 bp, nbp->b_bcount + boffset, bp->b_bcount); 1778 #endif 1779 bp->b_error = 0; 1780 bp->b_bcount = nbp->b_bcount + boffset; 1781 bp->b_resid = nbp->b_resid; 1782 kfree(nbp, M_DEVBUF); 1783 biodone(bio); 1784 } else if (nbp->b_bcount + boffset == bp->b_bcount) { 1785 /* 1786 * No more data terminates the chain 1787 */ 1788 #if SPEC_CHAIN_DEBUG & 1 1789 devfs_debug(DEVFS_DEBUG_DEBUG, 1790 "spec_strategy: chain %p finished bcount %d\n", 1791 bp, bp->b_bcount); 1792 #endif 1793 bp->b_error = 0; 1794 bp->b_resid = 0; 1795 kfree(nbp, M_DEVBUF); 1796 biodone(bio); 1797 } else { 1798 /* 1799 * Continue the chain 1800 */ 1801 boffset += nbp->b_bcount; 1802 nbp->b_data = bp->b_data + boffset; 1803 nbp->b_bcount = bp->b_bcount - boffset; 1804 if (nbp->b_bcount > chunksize) 1805 nbp->b_bcount = chunksize; 1806 nbp->b_bio1.bio_done = devfs_spec_strategy_done; 1807 nbp->b_bio1.bio_offset = bio->bio_offset + boffset; 1808 1809 #if SPEC_CHAIN_DEBUG & 1 1810 devfs_debug(DEVFS_DEBUG_DEBUG, 1811 "spec_strategy: chain %p offset %d/%d bcount %d\n", 1812 bp, boffset, bp->b_bcount, nbp->b_bcount); 1813 #endif 1814 1815 dev_dstrategy(nbp->b_vp->v_rdev, &nbp->b_bio1); 1816 } 1817 } 1818 1819 /* 1820 * spec_freeblks(struct vnode *a_vp, daddr_t a_addr, daddr_t a_length) 1821 */ 1822 static int 1823 devfs_spec_freeblks(struct vop_freeblks_args *ap) 1824 { 1825 struct buf *bp; 1826 1827 /* 1828 * XXX: This assumes that strategy does the deed right away. 1829 * XXX: this may not be TRTTD. 1830 */ 1831 KKASSERT(ap->a_vp->v_rdev != NULL); 1832 if ((dev_dflags(ap->a_vp->v_rdev) & D_CANFREE) == 0) 1833 return (0); 1834 bp = geteblk(ap->a_length); 1835 bp->b_cmd = BUF_CMD_FREEBLKS; 1836 bp->b_bio1.bio_offset = ap->a_offset; 1837 bp->b_bcount = ap->a_length; 1838 dev_dstrategy(ap->a_vp->v_rdev, &bp->b_bio1); 1839 return (0); 1840 } 1841 1842 /* 1843 * Implement degenerate case where the block requested is the block 1844 * returned, and assume that the entire device is contiguous in regards 1845 * to the contiguous block range (runp and runb). 1846 * 1847 * spec_bmap(struct vnode *a_vp, off_t a_loffset, 1848 * off_t *a_doffsetp, int *a_runp, int *a_runb) 1849 */ 1850 static int 1851 devfs_spec_bmap(struct vop_bmap_args *ap) 1852 { 1853 if (ap->a_doffsetp != NULL) 1854 *ap->a_doffsetp = ap->a_loffset; 1855 if (ap->a_runp != NULL) 1856 *ap->a_runp = MAXBSIZE; 1857 if (ap->a_runb != NULL) { 1858 if (ap->a_loffset < MAXBSIZE) 1859 *ap->a_runb = (int)ap->a_loffset; 1860 else 1861 *ap->a_runb = MAXBSIZE; 1862 } 1863 return (0); 1864 } 1865 1866 1867 /* 1868 * Special device advisory byte-level locks. 1869 * 1870 * spec_advlock(struct vnode *a_vp, caddr_t a_id, int a_op, 1871 * struct flock *a_fl, int a_flags) 1872 */ 1873 /* ARGSUSED */ 1874 static int 1875 devfs_spec_advlock(struct vop_advlock_args *ap) 1876 { 1877 return ((ap->a_flags & F_POSIX) ? EINVAL : EOPNOTSUPP); 1878 } 1879 1880 static void 1881 devfs_spec_getpages_iodone(struct bio *bio) 1882 { 1883 bio->bio_buf->b_cmd = BUF_CMD_DONE; 1884 wakeup(bio->bio_buf); 1885 } 1886 1887 /* 1888 * spec_getpages() - get pages associated with device vnode. 1889 * 1890 * Note that spec_read and spec_write do not use the buffer cache, so we 1891 * must fully implement getpages here. 1892 */ 1893 static int 1894 devfs_spec_getpages(struct vop_getpages_args *ap) 1895 { 1896 vm_offset_t kva; 1897 int error; 1898 int i, pcount, size; 1899 struct buf *bp; 1900 vm_page_t m; 1901 vm_ooffset_t offset; 1902 int toff, nextoff, nread; 1903 struct vnode *vp = ap->a_vp; 1904 int blksiz; 1905 int gotreqpage; 1906 1907 error = 0; 1908 pcount = round_page(ap->a_count) / PAGE_SIZE; 1909 1910 /* 1911 * Calculate the offset of the transfer and do sanity check. 1912 */ 1913 offset = IDX_TO_OFF(ap->a_m[0]->pindex) + ap->a_offset; 1914 1915 /* 1916 * Round up physical size for real devices. We cannot round using 1917 * v_mount's block size data because v_mount has nothing to do with 1918 * the device. i.e. it's usually '/dev'. We need the physical block 1919 * size for the device itself. 1920 * 1921 * We can't use v_rdev->si_mountpoint because it only exists when the 1922 * block device is mounted. However, we can use v_rdev. 1923 */ 1924 if (vn_isdisk(vp, NULL)) 1925 blksiz = vp->v_rdev->si_bsize_phys; 1926 else 1927 blksiz = DEV_BSIZE; 1928 1929 size = (ap->a_count + blksiz - 1) & ~(blksiz - 1); 1930 1931 bp = getpbuf(NULL); 1932 kva = (vm_offset_t)bp->b_data; 1933 1934 /* 1935 * Map the pages to be read into the kva. 1936 */ 1937 pmap_qenter(kva, ap->a_m, pcount); 1938 1939 /* Build a minimal buffer header. */ 1940 bp->b_cmd = BUF_CMD_READ; 1941 bp->b_bcount = size; 1942 bp->b_resid = 0; 1943 bp->b_runningbufspace = size; 1944 if (size) { 1945 runningbufspace += bp->b_runningbufspace; 1946 ++runningbufcount; 1947 } 1948 1949 bp->b_bio1.bio_offset = offset; 1950 bp->b_bio1.bio_done = devfs_spec_getpages_iodone; 1951 1952 mycpu->gd_cnt.v_vnodein++; 1953 mycpu->gd_cnt.v_vnodepgsin += pcount; 1954 1955 /* Do the input. */ 1956 vn_strategy(ap->a_vp, &bp->b_bio1); 1957 1958 crit_enter(); 1959 1960 /* We definitely need to be at splbio here. */ 1961 while (bp->b_cmd != BUF_CMD_DONE) 1962 tsleep(bp, 0, "spread", 0); 1963 1964 crit_exit(); 1965 1966 if (bp->b_flags & B_ERROR) { 1967 if (bp->b_error) 1968 error = bp->b_error; 1969 else 1970 error = EIO; 1971 } 1972 1973 /* 1974 * If EOF is encountered we must zero-extend the result in order 1975 * to ensure that the page does not contain garabge. When no 1976 * error occurs, an early EOF is indicated if b_bcount got truncated. 1977 * b_resid is relative to b_bcount and should be 0, but some devices 1978 * might indicate an EOF with b_resid instead of truncating b_bcount. 1979 */ 1980 nread = bp->b_bcount - bp->b_resid; 1981 if (nread < ap->a_count) 1982 bzero((caddr_t)kva + nread, ap->a_count - nread); 1983 pmap_qremove(kva, pcount); 1984 1985 gotreqpage = 0; 1986 for (i = 0, toff = 0; i < pcount; i++, toff = nextoff) { 1987 nextoff = toff + PAGE_SIZE; 1988 m = ap->a_m[i]; 1989 1990 m->flags &= ~PG_ZERO; 1991 1992 /* 1993 * NOTE: vm_page_undirty/clear_dirty etc do not clear the 1994 * pmap modified bit. pmap modified bit should have 1995 * already been cleared. 1996 */ 1997 if (nextoff <= nread) { 1998 m->valid = VM_PAGE_BITS_ALL; 1999 vm_page_undirty(m); 2000 } else if (toff < nread) { 2001 /* 2002 * Since this is a VM request, we have to supply the 2003 * unaligned offset to allow vm_page_set_valid() 2004 * to zero sub-DEV_BSIZE'd portions of the page. 2005 */ 2006 vm_page_set_valid(m, 0, nread - toff); 2007 vm_page_clear_dirty_end_nonincl(m, 0, nread - toff); 2008 } else { 2009 m->valid = 0; 2010 vm_page_undirty(m); 2011 } 2012 2013 if (i != ap->a_reqpage) { 2014 /* 2015 * Just in case someone was asking for this page we 2016 * now tell them that it is ok to use. 2017 */ 2018 if (!error || (m->valid == VM_PAGE_BITS_ALL)) { 2019 if (m->valid) { 2020 if (m->flags & PG_WANTED) { 2021 vm_page_activate(m); 2022 } else { 2023 vm_page_deactivate(m); 2024 } 2025 vm_page_wakeup(m); 2026 } else { 2027 vm_page_free(m); 2028 } 2029 } else { 2030 vm_page_free(m); 2031 } 2032 } else if (m->valid) { 2033 gotreqpage = 1; 2034 /* 2035 * Since this is a VM request, we need to make the 2036 * entire page presentable by zeroing invalid sections. 2037 */ 2038 if (m->valid != VM_PAGE_BITS_ALL) 2039 vm_page_zero_invalid(m, FALSE); 2040 } 2041 } 2042 if (!gotreqpage) { 2043 m = ap->a_m[ap->a_reqpage]; 2044 devfs_debug(DEVFS_DEBUG_WARNING, 2045 "spec_getpages:(%s) I/O read failure: (error=%d) bp %p vp %p\n", 2046 devtoname(vp->v_rdev), error, bp, bp->b_vp); 2047 devfs_debug(DEVFS_DEBUG_WARNING, 2048 " size: %d, resid: %d, a_count: %d, valid: 0x%x\n", 2049 size, bp->b_resid, ap->a_count, m->valid); 2050 devfs_debug(DEVFS_DEBUG_WARNING, 2051 " nread: %d, reqpage: %d, pindex: %lu, pcount: %d\n", 2052 nread, ap->a_reqpage, (u_long)m->pindex, pcount); 2053 /* 2054 * Free the buffer header back to the swap buffer pool. 2055 */ 2056 relpbuf(bp, NULL); 2057 return VM_PAGER_ERROR; 2058 } 2059 /* 2060 * Free the buffer header back to the swap buffer pool. 2061 */ 2062 relpbuf(bp, NULL); 2063 if (DEVFS_NODE(ap->a_vp)) 2064 nanotime(&DEVFS_NODE(ap->a_vp)->mtime); 2065 return VM_PAGER_OK; 2066 } 2067 2068 static __inline 2069 int 2070 sequential_heuristic(struct uio *uio, struct file *fp) 2071 { 2072 /* 2073 * Sequential heuristic - detect sequential operation 2074 */ 2075 if ((uio->uio_offset == 0 && fp->f_seqcount > 0) || 2076 uio->uio_offset == fp->f_nextoff) { 2077 /* 2078 * XXX we assume that the filesystem block size is 2079 * the default. Not true, but still gives us a pretty 2080 * good indicator of how sequential the read operations 2081 * are. 2082 */ 2083 int tmpseq = fp->f_seqcount; 2084 2085 tmpseq += (uio->uio_resid + BKVASIZE - 1) / BKVASIZE; 2086 if (tmpseq > IO_SEQMAX) 2087 tmpseq = IO_SEQMAX; 2088 fp->f_seqcount = tmpseq; 2089 return(fp->f_seqcount << IO_SEQSHIFT); 2090 } 2091 2092 /* 2093 * Not sequential, quick draw-down of seqcount 2094 */ 2095 if (fp->f_seqcount > 1) 2096 fp->f_seqcount = 1; 2097 else 2098 fp->f_seqcount = 0; 2099 return(0); 2100 } 2101