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sys/bsd/miscfs/specfs/spec_vnops.c
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1 /* 2 * Copyright (c) 2000-2002 Apple Computer, Inc. All rights reserved. 3 * 4 * @APPLE_LICENSE_HEADER_START@ 5 * 6 * Copyright (c) 1999-2003 Apple Computer, Inc. All Rights Reserved. 7 * 8 * This file contains Original Code and/or Modifications of Original Code 9 * as defined in and that are subject to the Apple Public Source License 10 * Version 2.0 (the 'License'). You may not use this file except in 11 * compliance with the License. Please obtain a copy of the License at 12 * http://www.opensource.apple.com/apsl/ and read it before using this 13 * file. 14 * 15 * The Original Code and all software distributed under the License are 16 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER 17 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, 18 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, 19 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. 20 * Please see the License for the specific language governing rights and 21 * limitations under the License. 22 * 23 * @APPLE_LICENSE_HEADER_END@ 24 */ 25 /* Copyright (c) 1995 NeXT Computer, Inc. All Rights Reserved */ 26 /* 27 * Copyright (c) 1989, 1993, 1995 28 * The Regents of the University of California. All rights reserved. 29 * 30 * Redistribution and use in source and binary forms, with or without 31 * modification, are permitted provided that the following conditions 32 * are met: 33 * 1. Redistributions of source code must retain the above copyright 34 * notice, this list of conditions and the following disclaimer. 35 * 2. Redistributions in binary form must reproduce the above copyright 36 * notice, this list of conditions and the following disclaimer in the 37 * documentation and/or other materials provided with the distribution. 38 * 3. All advertising materials mentioning features or use of this software 39 * must display the following acknowledgement: 40 * This product includes software developed by the University of 41 * California, Berkeley and its contributors. 42 * 4. Neither the name of the University nor the names of its contributors 43 * may be used to endorse or promote products derived from this software 44 * without specific prior written permission. 45 * 46 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 47 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 48 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 49 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 50 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 51 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 52 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 53 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 54 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 55 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 56 * SUCH DAMAGE. 57 * 58 * @(#)spec_vnops.c 8.14 (Berkeley) 5/21/95 59 */ 60 61 #include <sys/param.h> 62 #include <sys/proc.h> 63 #include <sys/systm.h> 64 #include <sys/kernel.h> 65 #include <sys/conf.h> 66 #include <sys/buf.h> 67 #include <sys/mount.h> 68 #include <sys/namei.h> 69 #include <sys/vnode.h> 70 #include <sys/stat.h> 71 #include <sys/errno.h> 72 #include <sys/ioctl.h> 73 #include <sys/file.h> 74 #include <sys/malloc.h> 75 #include <sys/disk.h> 76 #include <miscfs/specfs/specdev.h> 77 #include <vfs/vfs_support.h> 78 79 #include <sys/kdebug.h> 80 81 struct vnode *speclisth[SPECHSZ]; 82 83 /* symbolic sleep message strings for devices */ 84 char devopn[] = "devopn"; 85 char devio[] = "devio"; 86 char devwait[] = "devwait"; 87 char devin[] = "devin"; 88 char devout[] = "devout"; 89 char devioc[] = "devioc"; 90 char devcls[] = "devcls"; 91 92 #define VOPFUNC int (*)(void *) 93 94 int (**spec_vnodeop_p)(void *); 95 struct vnodeopv_entry_desc spec_vnodeop_entries[] = { 96 { &vop_default_desc, (VOPFUNC)vn_default_error }, 97 { &vop_lookup_desc, (VOPFUNC)spec_lookup }, /* lookup */ 98 { &vop_create_desc, (VOPFUNC)err_create }, /* create */ 99 { &vop_mknod_desc, (VOPFUNC)err_mknod }, /* mknod */ 100 { &vop_open_desc, (VOPFUNC)spec_open }, /* open */ 101 { &vop_close_desc, (VOPFUNC)spec_close }, /* close */ 102 { &vop_access_desc, (VOPFUNC)spec_access }, /* access */ 103 { &vop_getattr_desc, (VOPFUNC)spec_getattr }, /* getattr */ 104 { &vop_setattr_desc, (VOPFUNC)spec_setattr }, /* setattr */ 105 { &vop_read_desc, (VOPFUNC)spec_read }, /* read */ 106 { &vop_write_desc, (VOPFUNC)spec_write }, /* write */ 107 { &vop_lease_desc, (VOPFUNC)nop_lease }, /* lease */ 108 { &vop_ioctl_desc, (VOPFUNC)spec_ioctl }, /* ioctl */ 109 { &vop_select_desc, (VOPFUNC)spec_select }, /* select */ 110 { &vop_revoke_desc, (VOPFUNC)nop_revoke }, /* revoke */ 111 { &vop_mmap_desc, (VOPFUNC)err_mmap }, /* mmap */ 112 { &vop_fsync_desc, (VOPFUNC)spec_fsync }, /* fsync */ 113 { &vop_seek_desc, (VOPFUNC)err_seek }, /* seek */ 114 { &vop_remove_desc, (VOPFUNC)err_remove }, /* remove */ 115 { &vop_link_desc, (VOPFUNC)err_link }, /* link */ 116 { &vop_rename_desc, (VOPFUNC)err_rename }, /* rename */ 117 { &vop_mkdir_desc, (VOPFUNC)err_mkdir }, /* mkdir */ 118 { &vop_rmdir_desc, (VOPFUNC)err_rmdir }, /* rmdir */ 119 { &vop_symlink_desc, (VOPFUNC)err_symlink }, /* symlink */ 120 { &vop_readdir_desc, (VOPFUNC)err_readdir }, /* readdir */ 121 { &vop_readlink_desc, (VOPFUNC)err_readlink }, /* readlink */ 122 { &vop_abortop_desc, (VOPFUNC)err_abortop }, /* abortop */ 123 { &vop_inactive_desc, (VOPFUNC)nop_inactive }, /* inactive */ 124 { &vop_reclaim_desc, (VOPFUNC)nop_reclaim }, /* reclaim */ 125 { &vop_lock_desc, (VOPFUNC)nop_lock }, /* lock */ 126 { &vop_unlock_desc, (VOPFUNC)nop_unlock }, /* unlock */ 127 { &vop_bmap_desc, (VOPFUNC)spec_bmap }, /* bmap */ 128 { &vop_strategy_desc, (VOPFUNC)spec_strategy }, /* strategy */ 129 { &vop_print_desc, (VOPFUNC)spec_print }, /* print */ 130 { &vop_islocked_desc, (VOPFUNC)nop_islocked }, /* islocked */ 131 { &vop_pathconf_desc, (VOPFUNC)spec_pathconf }, /* pathconf */ 132 { &vop_advlock_desc, (VOPFUNC)err_advlock }, /* advlock */ 133 { &vop_blkatoff_desc, (VOPFUNC)err_blkatoff }, /* blkatoff */ 134 { &vop_valloc_desc, (VOPFUNC)err_valloc }, /* valloc */ 135 { &vop_vfree_desc, (VOPFUNC)err_vfree }, /* vfree */ 136 { &vop_truncate_desc, (VOPFUNC)nop_truncate }, /* truncate */ 137 { &vop_update_desc, (VOPFUNC)nop_update }, /* update */ 138 { &vop_bwrite_desc, (VOPFUNC)spec_bwrite }, /* bwrite */ 139 { &vop_devblocksize_desc, (VOPFUNC)spec_devblocksize }, /* devblocksize */ 140 { &vop_pagein_desc, (VOPFUNC)err_pagein }, /* Pagein */ 141 { &vop_pageout_desc, (VOPFUNC)err_pageout }, /* Pageout */ 142 { &vop_copyfile_desc, (VOPFUNC)err_copyfile }, /* Copyfile */ 143 { &vop_blktooff_desc, (VOPFUNC)spec_blktooff }, /* blktooff */ 144 { &vop_offtoblk_desc, (VOPFUNC)spec_offtoblk }, /* offtoblk */ 145 { &vop_cmap_desc, (VOPFUNC)spec_cmap }, /* cmap */ 146 { (struct vnodeop_desc*)NULL, (int(*)())NULL } 147 }; 148 struct vnodeopv_desc spec_vnodeop_opv_desc = 149 { &spec_vnodeop_p, spec_vnodeop_entries }; 150 151 /* 152 * Trivial lookup routine that always fails. 153 */ 154 int 155 spec_lookup(ap) 156 struct vop_lookup_args /* { 157 struct vnode *a_dvp; 158 struct vnode **a_vpp; 159 struct componentname *a_cnp; 160 } */ *ap; 161 { 162 163 *ap->a_vpp = NULL; 164 return (ENOTDIR); 165 } 166 167 void 168 set_blocksize(struct vnode *vp, dev_t dev) 169 { 170 int (*size)(); 171 int rsize; 172 173 if ((major(dev) < nblkdev) && (size = bdevsw[major(dev)].d_psize)) { 174 rsize = (*size)(dev); 175 if (rsize <= 0) /* did size fail? */ 176 vp->v_specsize = DEV_BSIZE; 177 else 178 vp->v_specsize = rsize; 179 } 180 else 181 vp->v_specsize = DEV_BSIZE; 182 } 183 184 void 185 set_fsblocksize(struct vnode *vp) 186 { 187 188 if (vp->v_type == VBLK) { 189 dev_t dev = (dev_t)vp->v_rdev; 190 int maj = major(dev); 191 192 if ((u_int)maj >= nblkdev) 193 return; 194 195 set_blocksize(vp, dev); 196 } 197 198 } 199 200 201 /* 202 * Open a special file. 203 */ 204 /* ARGSUSED */ 205 spec_open(ap) 206 struct vop_open_args /* { 207 struct vnode *a_vp; 208 int a_mode; 209 struct ucred *a_cred; 210 struct proc *a_p; 211 } */ *ap; 212 { 213 struct proc *p = ap->a_p; 214 struct vnode *bvp, *vp = ap->a_vp; 215 dev_t bdev, dev = (dev_t)vp->v_rdev; 216 int maj = major(dev); 217 int error; 218 219 /* 220 * Don't allow open if fs is mounted -nodev. 221 */ 222 if (vp->v_mount && (vp->v_mount->mnt_flag & MNT_NODEV)) 223 return (ENXIO); 224 225 switch (vp->v_type) { 226 227 case VCHR: 228 if ((u_int)maj >= nchrdev) 229 return (ENXIO); 230 if (ap->a_cred != FSCRED && (ap->a_mode & FWRITE)) { 231 /* 232 * When running in very secure mode, do not allow 233 * opens for writing of any disk character devices. 234 */ 235 if (securelevel >= 2 && isdisk(dev, VCHR)) 236 return (EPERM); 237 /* 238 * When running in secure mode, do not allow opens 239 * for writing of /dev/mem, /dev/kmem, or character 240 * devices whose corresponding block devices are 241 * currently mounted. 242 */ 243 if (securelevel >= 1) { 244 if ((bdev = chrtoblk(dev)) != NODEV && 245 vfinddev(bdev, VBLK, &bvp) && 246 bvp->v_usecount > 0 && 247 (error = vfs_mountedon(bvp))) 248 return (error); 249 if (iskmemdev(dev)) 250 return (EPERM); 251 } 252 } 253 if (cdevsw[maj].d_type == D_TTY) 254 vp->v_flag |= VISTTY; 255 VOP_UNLOCK(vp, 0, p); 256 error = (*cdevsw[maj].d_open)(dev, ap->a_mode, S_IFCHR, p); 257 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, p); 258 return (error); 259 260 case VBLK: 261 if ((u_int)maj >= nblkdev) 262 return (ENXIO); 263 /* 264 * When running in very secure mode, do not allow 265 * opens for writing of any disk block devices. 266 */ 267 if (securelevel >= 2 && ap->a_cred != FSCRED && 268 (ap->a_mode & FWRITE) && bdevsw[maj].d_type == D_DISK) 269 return (EPERM); 270 /* 271 * Do not allow opens of block devices that are 272 * currently mounted. 273 */ 274 if (error = vfs_mountedon(vp)) 275 return (error); 276 error = (*bdevsw[maj].d_open)(dev, ap->a_mode, S_IFBLK, p); 277 if (!error) { 278 u_int64_t blkcnt; 279 u_int32_t blksize; 280 281 set_blocksize(vp, dev); 282 283 /* 284 * Cache the size in bytes of the block device for later 285 * use by spec_write(). 286 */ 287 vp->v_specdevsize = (u_int64_t)0; /* Default: Can't get */ 288 if (!VOP_IOCTL(vp, DKIOCGETBLOCKSIZE, (caddr_t)&blksize, 0, NOCRED, p)) { 289 /* Switch to 512 byte sectors (temporarily) */ 290 u_int32_t size512 = 512; 291 292 if (!VOP_IOCTL(vp, DKIOCSETBLOCKSIZE, (caddr_t)&size512, FWRITE, NOCRED, p)) { 293 /* Get the number of 512 byte physical blocks. */ 294 if (!VOP_IOCTL(vp, DKIOCGETBLOCKCOUNT, (caddr_t)&blkcnt, 0, NOCRED, p)) { 295 vp->v_specdevsize = blkcnt * (u_int64_t)size512; 296 } 297 } 298 /* If it doesn't set back, we can't recover */ 299 if (VOP_IOCTL(vp, DKIOCSETBLOCKSIZE, (caddr_t)&blksize, FWRITE, NOCRED, p)) 300 error = ENXIO; 301 } 302 } 303 return(error); 304 } 305 return (0); 306 } 307 308 /* 309 * Vnode op for read 310 */ 311 /* ARGSUSED */ 312 spec_read(ap) 313 struct vop_read_args /* { 314 struct vnode *a_vp; 315 struct uio *a_uio; 316 int a_ioflag; 317 struct ucred *a_cred; 318 } */ *ap; 319 { 320 register struct vnode *vp = ap->a_vp; 321 register struct uio *uio = ap->a_uio; 322 struct proc *p = uio->uio_procp; 323 struct buf *bp; 324 daddr_t bn, nextbn; 325 long bsize, bscale; 326 int devBlockSize=0; 327 int n, on, majordev, (*ioctl)(); 328 int error = 0; 329 dev_t dev; 330 331 #if DIAGNOSTIC 332 if (uio->uio_rw != UIO_READ) 333 panic("spec_read mode"); 334 if (uio->uio_segflg == UIO_USERSPACE && uio->uio_procp != current_proc()) 335 panic("spec_read proc"); 336 #endif 337 if (uio->uio_resid == 0) 338 return (0); 339 340 switch (vp->v_type) { 341 342 case VCHR: 343 VOP_UNLOCK(vp, 0, p); 344 error = (*cdevsw[major(vp->v_rdev)].d_read) 345 (vp->v_rdev, uio, ap->a_ioflag); 346 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, p); 347 return (error); 348 349 case VBLK: 350 if (uio->uio_offset < 0) 351 return (EINVAL); 352 353 dev = vp->v_rdev; 354 355 devBlockSize = vp->v_specsize; 356 357 if (devBlockSize > PAGE_SIZE) 358 return (EINVAL); 359 360 bscale = PAGE_SIZE / devBlockSize; 361 bsize = bscale * devBlockSize; 362 363 do { 364 on = uio->uio_offset % bsize; 365 366 bn = (uio->uio_offset / devBlockSize) &~ (bscale - 1); 367 368 if (vp->v_lastr + bscale == bn) { 369 nextbn = bn + bscale; 370 error = breadn(vp, bn, (int)bsize, &nextbn, 371 (int *)&bsize, 1, NOCRED, &bp); 372 } else 373 error = bread(vp, bn, (int)bsize, NOCRED, &bp); 374 375 vp->v_lastr = bn; 376 n = bsize - bp->b_resid; 377 if ((on > n) || error) { 378 if (!error) 379 error = EINVAL; 380 brelse(bp); 381 return (error); 382 } 383 n = min((unsigned)(n - on), uio->uio_resid); 384 385 error = uiomove((char *)bp->b_data + on, n, uio); 386 if (n + on == bsize) 387 bp->b_flags |= B_AGE; 388 brelse(bp); 389 } while (error == 0 && uio->uio_resid > 0 && n != 0); 390 return (error); 391 392 default: 393 panic("spec_read type"); 394 } 395 /* NOTREACHED */ 396 } 397 398 /* 399 * Vnode op for write 400 */ 401 /* ARGSUSED */ 402 spec_write(ap) 403 struct vop_write_args /* { 404 struct vnode *a_vp; 405 struct uio *a_uio; 406 int a_ioflag; 407 struct ucred *a_cred; 408 } */ *ap; 409 { 410 register struct vnode *vp = ap->a_vp; 411 register struct uio *uio = ap->a_uio; 412 struct proc *p = uio->uio_procp; 413 struct buf *bp; 414 daddr_t bn; 415 int bsize, blkmask, bscale; 416 register int io_sync; 417 register int io_size; 418 int devBlockSize=0; 419 register int n, on; 420 int error = 0; 421 dev_t dev; 422 423 #if DIAGNOSTIC 424 if (uio->uio_rw != UIO_WRITE) 425 panic("spec_write mode"); 426 if (uio->uio_segflg == UIO_USERSPACE && uio->uio_procp != current_proc()) 427 panic("spec_write proc"); 428 #endif 429 430 switch (vp->v_type) { 431 432 case VCHR: 433 VOP_UNLOCK(vp, 0, p); 434 error = (*cdevsw[major(vp->v_rdev)].d_write) 435 (vp->v_rdev, uio, ap->a_ioflag); 436 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, p); 437 return (error); 438 439 case VBLK: 440 if (uio->uio_resid == 0) 441 return (0); 442 if (uio->uio_offset < 0) 443 return (EINVAL); 444 445 io_sync = (ap->a_ioflag & IO_SYNC); 446 io_size = uio->uio_resid; 447 448 dev = (vp->v_rdev); 449 450 devBlockSize = vp->v_specsize; 451 if (devBlockSize > PAGE_SIZE) 452 return(EINVAL); 453 454 bscale = PAGE_SIZE / devBlockSize; 455 blkmask = bscale - 1; 456 bsize = bscale * devBlockSize; 457 458 459 do { 460 bn = (uio->uio_offset / devBlockSize) &~ blkmask; 461 on = uio->uio_offset % bsize; 462 463 n = min((unsigned)(bsize - on), uio->uio_resid); 464 465 /* 466 * Use getblk() as an optimization IFF: 467 * 468 * 1) We are reading exactly a block on a block 469 * aligned boundary 470 * 2) We know the size of the device from spec_open 471 * 3) The read doesn't span the end of the device 472 * 473 * Otherwise, we fall back on bread(). 474 */ 475 if (n == bsize && 476 vp->v_specdevsize != (u_int64_t)0 && 477 (uio->uio_offset + (u_int64_t)n) > vp->v_specdevsize) { 478 /* reduce the size of the read to what is there */ 479 n = (uio->uio_offset + (u_int64_t)n) - vp->v_specdevsize; 480 } 481 482 if (n == bsize) 483 bp = getblk(vp, bn, bsize, 0, 0, BLK_WRITE); 484 else 485 error = bread(vp, bn, bsize, NOCRED, &bp); 486 487 /* Translate downstream error for upstream, if needed */ 488 if (!error) { 489 error = bp->b_error; 490 if (!error && (bp->b_flags & B_ERROR) != 0) { 491 error = EIO; 492 } 493 } 494 if (error) { 495 brelse(bp); 496 return (error); 497 } 498 n = min(n, bsize - bp->b_resid); 499 500 error = uiomove((char *)bp->b_data + on, n, uio); 501 502 bp->b_flags |= B_AGE; 503 504 if (io_sync) 505 bwrite(bp); 506 else { 507 if ((n + on) == bsize) 508 bawrite(bp); 509 else 510 bdwrite(bp); 511 } 512 } while (error == 0 && uio->uio_resid > 0 && n != 0); 513 return (error); 514 515 default: 516 panic("spec_write type"); 517 } 518 /* NOTREACHED */ 519 } 520 521 /* 522 * Device ioctl operation. 523 */ 524 /* ARGSUSED */ 525 spec_ioctl(ap) 526 struct vop_ioctl_args /* { 527 struct vnode *a_vp; 528 int a_command; 529 caddr_t a_data; 530 int a_fflag; 531 struct ucred *a_cred; 532 struct proc *a_p; 533 } */ *ap; 534 { 535 dev_t dev = ap->a_vp->v_rdev; 536 537 switch (ap->a_vp->v_type) { 538 539 case VCHR: 540 return ((*cdevsw[major(dev)].d_ioctl)(dev, ap->a_command, ap->a_data, 541 ap->a_fflag, ap->a_p)); 542 543 case VBLK: 544 if (ap->a_command == 0 && (int)ap->a_data == B_TAPE) 545 if (bdevsw[major(dev)].d_type == D_TAPE) 546 return (0); 547 else 548 return (1); 549 return ((*bdevsw[major(dev)].d_ioctl)(dev, ap->a_command, ap->a_data, 550 ap->a_fflag, ap->a_p)); 551 552 default: 553 panic("spec_ioctl"); 554 /* NOTREACHED */ 555 } 556 } 557 558 /* ARGSUSED */ 559 spec_select(ap) 560 struct vop_select_args /* { 561 struct vnode *a_vp; 562 int a_which; 563 int a_fflags; 564 struct ucred *a_cred; 565 void * a_wql; 566 struct proc *a_p; 567 } */ *ap; 568 { 569 register dev_t dev; 570 571 switch (ap->a_vp->v_type) { 572 573 default: 574 return (1); /* XXX */ 575 576 case VCHR: 577 dev = ap->a_vp->v_rdev; 578 return (*cdevsw[major(dev)].d_select)(dev, ap->a_which, ap->a_wql, ap->a_p); 579 } 580 } 581 /* 582 * Synch buffers associated with a block device 583 */ 584 /* ARGSUSED */ 585 int 586 spec_fsync(ap) 587 struct vop_fsync_args /* { 588 struct vnode *a_vp; 589 struct ucred *a_cred; 590 int a_waitfor; 591 struct proc *a_p; 592 } */ *ap; 593 { 594 register struct vnode *vp = ap->a_vp; 595 register struct buf *bp; 596 struct buf *nbp; 597 int s; 598 599 if (vp->v_type == VCHR) 600 return (0); 601 /* 602 * Flush all dirty buffers associated with a block device. 603 */ 604 loop: 605 s = splbio(); 606 for (bp = vp->v_dirtyblkhd.lh_first; bp; bp = nbp) { 607 nbp = bp->b_vnbufs.le_next; 608 // XXXdbg - don't flush locked blocks. they may be journaled. 609 if ((bp->b_flags & B_BUSY) || (bp->b_flags & B_LOCKED)) 610 continue; 611 if ((bp->b_flags & B_DELWRI) == 0) 612 panic("spec_fsync: not dirty"); 613 bremfree(bp); 614 bp->b_flags |= B_BUSY; 615 splx(s); 616 bawrite(bp); 617 goto loop; 618 } 619 if (ap->a_waitfor == MNT_WAIT) { 620 while (vp->v_numoutput) { 621 vp->v_flag |= VBWAIT; 622 tsleep((caddr_t)&vp->v_numoutput, PRIBIO + 1, "spec_fsync", 0); 623 } 624 #if DIAGNOSTIC 625 if (vp->v_dirtyblkhd.lh_first) { 626 vprint("spec_fsync: dirty", vp); 627 splx(s); 628 goto loop; 629 } 630 #endif 631 } 632 splx(s); 633 return (0); 634 } 635 636 /* 637 * Just call the device strategy routine 638 */ 639 spec_strategy(ap) 640 struct vop_strategy_args /* { 641 struct buf *a_bp; 642 } */ *ap; 643 { 644 struct buf *bp; 645 extern int hard_throttle_on_root; 646 647 bp = ap->a_bp; 648 649 if (kdebug_enable) { 650 int code = 0; 651 652 if (bp->b_flags & B_READ) 653 code |= DKIO_READ; 654 if (bp->b_flags & B_ASYNC) 655 code |= DKIO_ASYNC; 656 657 if (bp->b_flags & B_META) 658 code |= DKIO_META; 659 else if (bp->b_flags & (B_PGIN | B_PAGEOUT)) 660 code |= DKIO_PAGING; 661 662 KERNEL_DEBUG_CONSTANT(FSDBG_CODE(DBG_DKRW, code) | DBG_FUNC_NONE, 663 (unsigned int)bp, bp->b_dev, bp->b_blkno, bp->b_bcount, 0); 664 } 665 if ((bp->b_flags & B_PGIN) && (bp->b_vp->v_mount->mnt_kern_flag & MNTK_ROOTDEV)) 666 hard_throttle_on_root = 1; 667 668 (*bdevsw[major(bp->b_dev)].d_strategy)(bp); 669 return (0); 670 } 671 672 /* 673 * This is a noop, simply returning what one has been given. 674 */ 675 spec_bmap(ap) 676 struct vop_bmap_args /* { 677 struct vnode *a_vp; 678 daddr_t a_bn; 679 struct vnode **a_vpp; 680 daddr_t *a_bnp; 681 int *a_runp; 682 } */ *ap; 683 { 684 685 if (ap->a_vpp != NULL) 686 *ap->a_vpp = ap->a_vp; 687 if (ap->a_bnp != NULL) 688 *ap->a_bnp = ap->a_bn * (PAGE_SIZE / ap->a_vp->v_specsize); 689 if (ap->a_runp != NULL) 690 *ap->a_runp = (MAXPHYSIO / PAGE_SIZE) - 1; 691 return (0); 692 } 693 694 /* 695 * This is a noop, simply returning what one has been given. 696 */ 697 spec_cmap(ap) 698 struct vop_cmap_args /* { 699 struct vnode *a_vp; 700 off_t a_offset; 701 size_t a_size; 702 daddr_t *a_bpn; 703 size_t *a_run; 704 void *a_poff; 705 } */ *ap; 706 { 707 return (EOPNOTSUPP); 708 } 709 710 711 /* 712 * Device close routine 713 */ 714 /* ARGSUSED */ 715 spec_close(ap) 716 struct vop_close_args /* { 717 struct vnode *a_vp; 718 int a_fflag; 719 struct ucred *a_cred; 720 struct proc *a_p; 721 } */ *ap; 722 { 723 register struct vnode *vp = ap->a_vp; 724 dev_t dev = vp->v_rdev; 725 int (*devclose) __P((dev_t, int, int, struct proc *)); 726 int mode, error; 727 728 switch (vp->v_type) { 729 730 case VCHR: 731 /* 732 * Hack: a tty device that is a controlling terminal 733 * has a reference from the session structure. 734 * We cannot easily tell that a character device is 735 * a controlling terminal, unless it is the closing 736 * process' controlling terminal. In that case, 737 * if the reference count is 2 (this last descriptor 738 * plus the session), release the reference from the session. 739 */ 740 if (vcount(vp) == 2 && ap->a_p && 741 vp == ap->a_p->p_session->s_ttyvp) { 742 ap->a_p->p_session->s_ttyvp = NULL; 743 vrele(vp); 744 } 745 /* 746 * If the vnode is locked, then we are in the midst 747 * of forcably closing the device, otherwise we only 748 * close on last reference. 749 */ 750 if (vcount(vp) > 1 && (vp->v_flag & VXLOCK) == 0) 751 return (0); 752 devclose = cdevsw[major(dev)].d_close; 753 mode = S_IFCHR; 754 break; 755 756 case VBLK: 757 #ifdef DEVFS_IMPLEMENTS_LOCKING 758 /* 759 * On last close of a block device (that isn't mounted) 760 * we must invalidate any in core blocks, so that 761 * we can, for instance, change floppy disks. 762 */ 763 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, ap->a_p); 764 error = vinvalbuf(vp, V_SAVE, ap->a_cred, ap->a_p, 0, 0); 765 VOP_UNLOCK(vp, 0, ap->a_p); 766 if (error) 767 return (error); 768 /* 769 * We do not want to really close the device if it 770 * is still in use unless we are trying to close it 771 * forcibly. Since every use (buffer, vnode, swap, cmap) 772 * holds a reference to the vnode, and because we mark 773 * any other vnodes that alias this device, when the 774 * sum of the reference counts on all the aliased 775 * vnodes descends to one, we are on last close. 776 */ 777 if (vcount(vp) > 1 && (vp->v_flag & VXLOCK) == 0) 778 return (0); 779 #else /* DEVFS_IMPLEMENTS_LOCKING */ 780 /* 781 * We do not want to really close the device if it 782 * is still in use unless we are trying to close it 783 * forcibly. Since every use (buffer, vnode, swap, cmap) 784 * holds a reference to the vnode, and because we mark 785 * any other vnodes that alias this device, when the 786 * sum of the reference counts on all the aliased 787 * vnodes descends to one, we are on last close. 788 */ 789 if (vcount(vp) > 1 && (vp->v_flag & VXLOCK) == 0) 790 return (0); 791 792 /* 793 * On last close of a block device (that isn't mounted) 794 * we must invalidate any in core blocks, so that 795 * we can, for instance, change floppy disks. 796 */ 797 error = vinvalbuf(vp, V_SAVE, ap->a_cred, ap->a_p, 0, 0); 798 if (error) 799 return (error); 800 #endif /* DEVFS_IMPLEMENTS_LOCKING */ 801 devclose = bdevsw[major(dev)].d_close; 802 mode = S_IFBLK; 803 break; 804 805 default: 806 panic("spec_close: not special"); 807 } 808 809 return ((*devclose)(dev, ap->a_fflag, mode, ap->a_p)); 810 } 811 812 /* 813 * Print out the contents of a special device vnode. 814 */ 815 spec_print(ap) 816 struct vop_print_args /* { 817 struct vnode *a_vp; 818 } */ *ap; 819 { 820 821 printf("tag VT_NON, dev %d, %d\n", major(ap->a_vp->v_rdev), 822 minor(ap->a_vp->v_rdev)); 823 } 824 825 /* 826 * Return POSIX pathconf information applicable to special devices. 827 */ 828 spec_pathconf(ap) 829 struct vop_pathconf_args /* { 830 struct vnode *a_vp; 831 int a_name; 832 int *a_retval; 833 } */ *ap; 834 { 835 836 switch (ap->a_name) { 837 case _PC_LINK_MAX: 838 *ap->a_retval = LINK_MAX; 839 return (0); 840 case _PC_MAX_CANON: 841 *ap->a_retval = MAX_CANON; 842 return (0); 843 case _PC_MAX_INPUT: 844 *ap->a_retval = MAX_INPUT; 845 return (0); 846 case _PC_PIPE_BUF: 847 *ap->a_retval = PIPE_BUF; 848 return (0); 849 case _PC_CHOWN_RESTRICTED: 850 *ap->a_retval = 1; 851 return (0); 852 case _PC_VDISABLE: 853 *ap->a_retval = _POSIX_VDISABLE; 854 return (0); 855 default: 856 return (EINVAL); 857 } 858 /* NOTREACHED */ 859 } 860 861 int 862 spec_devblocksize(ap) 863 struct vop_devblocksize_args /* { 864 struct vnode *a_vp; 865 int *a_retval; 866 } */ *ap; 867 { 868 *ap->a_retval = (ap->a_vp->v_specsize); 869 return (0); 870 } 871 872 /* 873 * Special device failed operation 874 */ 875 spec_ebadf() 876 { 877 878 return (EBADF); 879 } 880 881 /* 882 * Special device bad operation 883 */ 884 spec_badop() 885 { 886 887 panic("spec_badop called"); 888 /* NOTREACHED */ 889 } 890 891 /* Blktooff derives file offset from logical block number */ 892 int 893 spec_blktooff(ap) 894 struct vop_blktooff_args /* { 895 struct vnode *a_vp; 896 daddr_t a_lblkno; 897 off_t *a_offset; 898 } */ *ap; 899 { 900 register struct vnode *vp = ap->a_vp; 901 902 switch (vp->v_type) { 903 case VCHR: 904 *ap->a_offset = (off_t)-1; /* failure */ 905 return (EOPNOTSUPP); 906 907 case VBLK: 908 printf("spec_blktooff: not implemented for VBLK\n"); 909 *ap->a_offset = (off_t)-1; /* failure */ 910 return (EOPNOTSUPP); 911 912 default: 913 panic("spec_blktooff type"); 914 } 915 /* NOTREACHED */ 916 } 917 918 /* Offtoblk derives logical block number from file offset */ 919 int 920 spec_offtoblk(ap) 921 struct vop_offtoblk_args /* { 922 struct vnode *a_vp; 923 off_t a_offset; 924 daddr_t *a_lblkno; 925 } */ *ap; 926 { 927 register struct vnode *vp = ap->a_vp; 928 929 switch (vp->v_type) { 930 case VCHR: 931 *ap->a_lblkno = (daddr_t)-1; /* failure */ 932 return (EOPNOTSUPP); 933 934 case VBLK: 935 printf("spec_offtoblk: not implemented for VBLK\n"); 936 *ap->a_lblkno = (daddr_t)-1; /* failure */ 937 return (EOPNOTSUPP); 938 939 default: 940 panic("spec_offtoblk type"); 941 } 942 /* NOTREACHED */ 943 }
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