| 1 | /* |
| 2 | * Copyright (c) 1989, 1993, 1995 |
| 3 | * The Regents of the University of California. All rights reserved. |
| 4 | * |
| 5 | * Redistribution and use in source and binary forms, with or without |
| 6 | * modification, are permitted provided that the following conditions |
| 7 | * are met: |
| 8 | * 1. Redistributions of source code must retain the above copyright |
| 9 | * notice, this list of conditions and the following disclaimer. |
| 10 | * 2. Redistributions in binary form must reproduce the above copyright |
| 11 | * notice, this list of conditions and the following disclaimer in the |
| 12 | * documentation and/or other materials provided with the distribution. |
| 13 | * 3. All advertising materials mentioning features or use of this software |
| 14 | * must display the following acknowledgement: |
| 15 | * This product includes software developed by the University of |
| 16 | * California, Berkeley and its contributors. |
| 17 | * 4. Neither the name of the University nor the names of its contributors |
| 18 | * may be used to endorse or promote products derived from this software |
| 19 | * without specific prior written permission. |
| 20 | * |
| 21 | * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND |
| 22 | * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| 23 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| 24 | * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE |
| 25 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
| 26 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
| 27 | * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
| 28 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
| 29 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
| 30 | * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| 31 | * SUCH DAMAGE. |
| 32 | * |
| 33 | * @(#)spec_vnops.c 8.14 (Berkeley) 5/21/95 |
| 34 | * $FreeBSD: src/sys/miscfs/specfs/spec_vnops.c,v 1.131.2.4 2001/02/26 04:23:20 jlemon Exp $ |
| 35 | */ |
| 36 | |
| 37 | #include <sys/param.h> |
| 38 | #include <sys/proc.h> |
| 39 | #include <sys/systm.h> |
| 40 | #include <sys/kernel.h> |
| 41 | #include <sys/conf.h> |
| 42 | #include <sys/buf.h> |
| 43 | #include <sys/mount.h> |
| 44 | #include <sys/vnode.h> |
| 45 | #include <sys/stat.h> |
| 46 | #include <sys/fcntl.h> |
| 47 | #include <sys/vmmeter.h> |
| 48 | #include <sys/tty.h> |
| 49 | |
| 50 | #include <vm/vm.h> |
| 51 | #include <vm/vm_object.h> |
| 52 | #include <vm/vm_page.h> |
| 53 | #include <vm/vm_pager.h> |
| 54 | |
| 55 | static int spec_advlock __P((struct vop_advlock_args *)); |
| 56 | static int spec_bmap __P((struct vop_bmap_args *)); |
| 57 | static int spec_close __P((struct vop_close_args *)); |
| 58 | static int spec_freeblks __P((struct vop_freeblks_args *)); |
| 59 | static int spec_fsync __P((struct vop_fsync_args *)); |
| 60 | static int spec_getpages __P((struct vop_getpages_args *)); |
| 61 | static int spec_inactive __P((struct vop_inactive_args *)); |
| 62 | static int spec_ioctl __P((struct vop_ioctl_args *)); |
| 63 | static int spec_open __P((struct vop_open_args *)); |
| 64 | static int spec_poll __P((struct vop_poll_args *)); |
| 65 | static int spec_kqfilter __P((struct vop_kqfilter_args *)); |
| 66 | static int spec_print __P((struct vop_print_args *)); |
| 67 | static int spec_read __P((struct vop_read_args *)); |
| 68 | static int spec_strategy __P((struct vop_strategy_args *)); |
| 69 | static int spec_write __P((struct vop_write_args *)); |
| 70 | |
| 71 | vop_t **spec_vnodeop_p; |
| 72 | static struct vnodeopv_entry_desc spec_vnodeop_entries[] = { |
| 73 | { &vop_default_desc, (vop_t *) vop_defaultop }, |
| 74 | { &vop_access_desc, (vop_t *) vop_ebadf }, |
| 75 | { &vop_advlock_desc, (vop_t *) spec_advlock }, |
| 76 | { &vop_bmap_desc, (vop_t *) spec_bmap }, |
| 77 | { &vop_close_desc, (vop_t *) spec_close }, |
| 78 | { &vop_create_desc, (vop_t *) vop_panic }, |
| 79 | { &vop_freeblks_desc, (vop_t *) spec_freeblks }, |
| 80 | { &vop_fsync_desc, (vop_t *) spec_fsync }, |
| 81 | { &vop_getpages_desc, (vop_t *) spec_getpages }, |
| 82 | { &vop_inactive_desc, (vop_t *) spec_inactive }, |
| 83 | { &vop_ioctl_desc, (vop_t *) spec_ioctl }, |
| 84 | { &vop_lease_desc, (vop_t *) vop_null }, |
| 85 | { &vop_link_desc, (vop_t *) vop_panic }, |
| 86 | { &vop_mkdir_desc, (vop_t *) vop_panic }, |
| 87 | { &vop_mknod_desc, (vop_t *) vop_panic }, |
| 88 | { &vop_open_desc, (vop_t *) spec_open }, |
| 89 | { &vop_pathconf_desc, (vop_t *) vop_stdpathconf }, |
| 90 | { &vop_poll_desc, (vop_t *) spec_poll }, |
| 91 | { &vop_kqfilter_desc, (vop_t *) spec_kqfilter }, |
| 92 | { &vop_print_desc, (vop_t *) spec_print }, |
| 93 | { &vop_read_desc, (vop_t *) spec_read }, |
| 94 | { &vop_readdir_desc, (vop_t *) vop_panic }, |
| 95 | { &vop_readlink_desc, (vop_t *) vop_panic }, |
| 96 | { &vop_reallocblks_desc, (vop_t *) vop_panic }, |
| 97 | { &vop_reclaim_desc, (vop_t *) vop_null }, |
| 98 | { &vop_remove_desc, (vop_t *) vop_panic }, |
| 99 | { &vop_rename_desc, (vop_t *) vop_panic }, |
| 100 | { &vop_rmdir_desc, (vop_t *) vop_panic }, |
| 101 | { &vop_setattr_desc, (vop_t *) vop_ebadf }, |
| 102 | { &vop_strategy_desc, (vop_t *) spec_strategy }, |
| 103 | { &vop_symlink_desc, (vop_t *) vop_panic }, |
| 104 | { &vop_write_desc, (vop_t *) spec_write }, |
| 105 | { NULL, NULL } |
| 106 | }; |
| 107 | static struct vnodeopv_desc spec_vnodeop_opv_desc = |
| 108 | { &spec_vnodeop_p, spec_vnodeop_entries }; |
| 109 | |
| 110 | VNODEOP_SET(spec_vnodeop_opv_desc); |
| 111 | |
| 112 | int |
| 113 | spec_vnoperate(ap) |
| 114 | struct vop_generic_args /* { |
| 115 | struct vnodeop_desc *a_desc; |
| 116 | <other random data follows, presumably> |
| 117 | } */ *ap; |
| 118 | { |
| 119 | return (VOCALL(spec_vnodeop_p, ap->a_desc->vdesc_offset, ap)); |
| 120 | } |
| 121 | |
| 122 | static void spec_getpages_iodone __P((struct buf *bp)); |
| 123 | |
| 124 | /* |
| 125 | * Open a special file. |
| 126 | */ |
| 127 | /* ARGSUSED */ |
| 128 | static int |
| 129 | spec_open(ap) |
| 130 | struct vop_open_args /* { |
| 131 | struct vnode *a_vp; |
| 132 | int a_mode; |
| 133 | struct ucred *a_cred; |
| 134 | struct proc *a_p; |
| 135 | } */ *ap; |
| 136 | { |
| 137 | struct proc *p = ap->a_p; |
| 138 | struct vnode *vp = ap->a_vp; |
| 139 | dev_t dev = vp->v_rdev; |
| 140 | int error; |
| 141 | struct cdevsw *dsw; |
| 142 | const char *cp; |
| 143 | |
| 144 | /* |
| 145 | * Don't allow open if fs is mounted -nodev. |
| 146 | */ |
| 147 | if (vp->v_mount && (vp->v_mount->mnt_flag & MNT_NODEV)) |
| 148 | return (ENXIO); |
| 149 | |
| 150 | dsw = devsw(dev); |
| 151 | if ( (dsw == NULL) || (dsw->d_open == NULL)) |
| 152 | return ENXIO; |
| 153 | |
| 154 | /* Make this field valid before any I/O in ->d_open */ |
| 155 | if (!dev->si_iosize_max) |
| 156 | dev->si_iosize_max = DFLTPHYS; |
| 157 | |
| 158 | /* |
| 159 | * XXX: Disks get special billing here, but it is mostly wrong. |
| 160 | * XXX: diskpartitions can overlap and the real checks should |
| 161 | * XXX: take this into account, and consequently they need to |
| 162 | * XXX: live in the diskslicing code. Some checks do. |
| 163 | */ |
| 164 | if (vn_isdisk(vp, NULL) && ap->a_cred != FSCRED && |
| 165 | (ap->a_mode & FWRITE)) { |
| 166 | /* |
| 167 | * Never allow opens for write if the device is mounted R/W |
| 168 | */ |
| 169 | if (vp->v_specmountpoint != NULL && |
| 170 | !(vp->v_specmountpoint->mnt_flag & MNT_RDONLY)) |
| 171 | return (EBUSY); |
| 172 | |
| 173 | /* |
| 174 | * When running in secure mode, do not allow opens |
| 175 | * for writing if the device is mounted |
| 176 | */ |
| 177 | if (securelevel >= 1 && vp->v_specmountpoint != NULL) |
| 178 | return (EPERM); |
| 179 | |
| 180 | /* |
| 181 | * When running in very secure mode, do not allow |
| 182 | * opens for writing of any devices. |
| 183 | */ |
| 184 | if (securelevel >= 2) |
| 185 | return (EPERM); |
| 186 | } |
| 187 | |
| 188 | /* XXX: Special casing of ttys for deadfs. Probably redundant */ |
| 189 | if (dsw->d_flags & D_TTY) |
| 190 | vp->v_flag |= VISTTY; |
| 191 | |
| 192 | VOP_UNLOCK(vp, 0, p); |
| 193 | error = (*dsw->d_open)(dev, ap->a_mode, S_IFCHR, p); |
| 194 | vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, p); |
| 195 | |
| 196 | if (error) |
| 197 | return (error); |
| 198 | |
| 199 | if (dsw->d_flags & D_TTY) { |
| 200 | if (dev->si_tty) { |
| 201 | struct tty *tp; |
| 202 | tp = dev->si_tty; |
| 203 | if (!tp->t_stop) { |
| 204 | printf("Warning:%s: no t_stop, using nottystop\n", devtoname(dev)); |
| 205 | tp->t_stop = nottystop; |
| 206 | } |
| 207 | } |
| 208 | } |
| 209 | |
| 210 | if (vn_isdisk(vp, NULL)) { |
| 211 | if (!dev->si_bsize_phys) |
| 212 | dev->si_bsize_phys = DEV_BSIZE; |
| 213 | } |
| 214 | if ((dsw->d_flags & D_DISK) == 0) { |
| 215 | cp = devtoname(dev); |
| 216 | if (*cp == '#' && (dsw->d_flags & D_NAGGED) == 0) { |
| 217 | printf("WARNING: driver %s should register devices with make_dev() (dev_t = \"%s\")\n", |
| 218 | dsw->d_name, cp); |
| 219 | dsw->d_flags |= D_NAGGED; |
| 220 | } |
| 221 | } |
| 222 | return (error); |
| 223 | } |
| 224 | |
| 225 | /* |
| 226 | * Vnode op for read |
| 227 | */ |
| 228 | /* ARGSUSED */ |
| 229 | static int |
| 230 | spec_read(ap) |
| 231 | struct vop_read_args /* { |
| 232 | struct vnode *a_vp; |
| 233 | struct uio *a_uio; |
| 234 | int a_ioflag; |
| 235 | struct ucred *a_cred; |
| 236 | } */ *ap; |
| 237 | { |
| 238 | struct vnode *vp; |
| 239 | struct proc *p; |
| 240 | struct uio *uio; |
| 241 | dev_t dev; |
| 242 | int error; |
| 243 | |
| 244 | vp = ap->a_vp; |
| 245 | dev = vp->v_rdev; |
| 246 | uio = ap->a_uio; |
| 247 | p = uio->uio_procp; |
| 248 | |
| 249 | if (uio->uio_resid == 0) |
| 250 | return (0); |
| 251 | |
| 252 | VOP_UNLOCK(vp, 0, p); |
| 253 | error = (*devsw(dev)->d_read) (dev, uio, ap->a_ioflag); |
| 254 | vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, p); |
| 255 | return (error); |
| 256 | } |
| 257 | |
| 258 | /* |
| 259 | * Vnode op for write |
| 260 | */ |
| 261 | /* ARGSUSED */ |
| 262 | static int |
| 263 | spec_write(ap) |
| 264 | struct vop_write_args /* { |
| 265 | struct vnode *a_vp; |
| 266 | struct uio *a_uio; |
| 267 | int a_ioflag; |
| 268 | struct ucred *a_cred; |
| 269 | } */ *ap; |
| 270 | { |
| 271 | struct vnode *vp; |
| 272 | struct proc *p; |
| 273 | struct uio *uio; |
| 274 | dev_t dev; |
| 275 | int error; |
| 276 | |
| 277 | vp = ap->a_vp; |
| 278 | dev = vp->v_rdev; |
| 279 | uio = ap->a_uio; |
| 280 | p = uio->uio_procp; |
| 281 | |
| 282 | VOP_UNLOCK(vp, 0, p); |
| 283 | error = (*devsw(dev)->d_write) (dev, uio, ap->a_ioflag); |
| 284 | vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, p); |
| 285 | return (error); |
| 286 | } |
| 287 | |
| 288 | /* |
| 289 | * Device ioctl operation. |
| 290 | */ |
| 291 | /* ARGSUSED */ |
| 292 | static int |
| 293 | spec_ioctl(ap) |
| 294 | struct vop_ioctl_args /* { |
| 295 | struct vnode *a_vp; |
| 296 | int a_command; |
| 297 | caddr_t a_data; |
| 298 | int a_fflag; |
| 299 | struct ucred *a_cred; |
| 300 | struct proc *a_p; |
| 301 | } */ *ap; |
| 302 | { |
| 303 | dev_t dev; |
| 304 | |
| 305 | dev = ap->a_vp->v_rdev; |
| 306 | return ((*devsw(dev)->d_ioctl)(dev, ap->a_command, |
| 307 | ap->a_data, ap->a_fflag, ap->a_p)); |
| 308 | } |
| 309 | |
| 310 | /* ARGSUSED */ |
| 311 | static int |
| 312 | spec_poll(ap) |
| 313 | struct vop_poll_args /* { |
| 314 | struct vnode *a_vp; |
| 315 | int a_events; |
| 316 | struct ucred *a_cred; |
| 317 | struct proc *a_p; |
| 318 | } */ *ap; |
| 319 | { |
| 320 | dev_t dev; |
| 321 | |
| 322 | dev = ap->a_vp->v_rdev; |
| 323 | return (*devsw(dev)->d_poll)(dev, ap->a_events, ap->a_p); |
| 324 | } |
| 325 | |
| 326 | /* ARGSUSED */ |
| 327 | static int |
| 328 | spec_kqfilter(ap) |
| 329 | struct vop_kqfilter_args /* { |
| 330 | struct vnode *a_vp; |
| 331 | struct knote *a_kn; |
| 332 | } */ *ap; |
| 333 | { |
| 334 | dev_t dev; |
| 335 | |
| 336 | dev = ap->a_vp->v_rdev; |
| 337 | if (devsw(dev)->d_flags & D_KQFILTER) |
| 338 | return (*devsw(dev)->d_kqfilter)(dev, ap->a_kn); |
| 339 | return (1); |
| 340 | } |
| 341 | |
| 342 | /* |
| 343 | * Synch buffers associated with a block device |
| 344 | */ |
| 345 | /* ARGSUSED */ |
| 346 | static int |
| 347 | spec_fsync(ap) |
| 348 | struct vop_fsync_args /* { |
| 349 | struct vnode *a_vp; |
| 350 | struct ucred *a_cred; |
| 351 | int a_waitfor; |
| 352 | struct proc *a_p; |
| 353 | } */ *ap; |
| 354 | { |
| 355 | struct vnode *vp = ap->a_vp; |
| 356 | struct buf *bp; |
| 357 | struct buf *nbp; |
| 358 | int s; |
| 359 | int maxretry = 10000; /* large, arbitrarily chosen */ |
| 360 | |
| 361 | if (!vn_isdisk(vp, NULL)) |
| 362 | return (0); |
| 363 | |
| 364 | loop1: |
| 365 | /* |
| 366 | * MARK/SCAN initialization to avoid infinite loops |
| 367 | */ |
| 368 | s = splbio(); |
| 369 | for (bp = TAILQ_FIRST(&vp->v_dirtyblkhd); bp; |
| 370 | bp = TAILQ_NEXT(bp, b_vnbufs)) { |
| 371 | bp->b_flags &= ~B_SCANNED; |
| 372 | } |
| 373 | splx(s); |
| 374 | |
| 375 | /* |
| 376 | * Flush all dirty buffers associated with a block device. |
| 377 | */ |
| 378 | loop2: |
| 379 | s = splbio(); |
| 380 | for (bp = TAILQ_FIRST(&vp->v_dirtyblkhd); bp; bp = nbp) { |
| 381 | nbp = TAILQ_NEXT(bp, b_vnbufs); |
| 382 | if ((bp->b_flags & B_SCANNED) != 0) |
| 383 | continue; |
| 384 | bp->b_flags |= B_SCANNED; |
| 385 | if (BUF_LOCK(bp, LK_EXCLUSIVE | LK_NOWAIT)) |
| 386 | continue; |
| 387 | if ((bp->b_flags & B_DELWRI) == 0) |
| 388 | panic("spec_fsync: not dirty"); |
| 389 | if ((vp->v_flag & VOBJBUF) && (bp->b_flags & B_CLUSTEROK)) { |
| 390 | BUF_UNLOCK(bp); |
| 391 | vfs_bio_awrite(bp); |
| 392 | splx(s); |
| 393 | } else { |
| 394 | bremfree(bp); |
| 395 | splx(s); |
| 396 | bawrite(bp); |
| 397 | } |
| 398 | goto loop2; |
| 399 | } |
| 400 | |
| 401 | /* |
| 402 | * If synchronous the caller expects us to completely resolve all |
| 403 | * dirty buffers in the system. Wait for in-progress I/O to |
| 404 | * complete (which could include background bitmap writes), then |
| 405 | * retry if dirty blocks still exist. |
| 406 | */ |
| 407 | if (ap->a_waitfor == MNT_WAIT) { |
| 408 | while (vp->v_numoutput) { |
| 409 | vp->v_flag |= VBWAIT; |
| 410 | (void) tsleep((caddr_t)&vp->v_numoutput, PRIBIO + 1, "spfsyn", 0); |
| 411 | } |
| 412 | if (!TAILQ_EMPTY(&vp->v_dirtyblkhd)) { |
| 413 | if (--maxretry != 0) { |
| 414 | splx(s); |
| 415 | goto loop1; |
| 416 | } |
| 417 | vprint("spec_fsync: giving up on dirty", vp); |
| 418 | } |
| 419 | } |
| 420 | splx(s); |
| 421 | return (0); |
| 422 | } |
| 423 | |
| 424 | static int |
| 425 | spec_inactive(ap) |
| 426 | struct vop_inactive_args /* { |
| 427 | struct vnode *a_vp; |
| 428 | struct proc *a_p; |
| 429 | } */ *ap; |
| 430 | { |
| 431 | |
| 432 | VOP_UNLOCK(ap->a_vp, 0, ap->a_p); |
| 433 | return (0); |
| 434 | } |
| 435 | |
| 436 | /* |
| 437 | * Just call the device strategy routine |
| 438 | */ |
| 439 | static int |
| 440 | spec_strategy(ap) |
| 441 | struct vop_strategy_args /* { |
| 442 | struct vnode *a_vp; |
| 443 | struct buf *a_bp; |
| 444 | } */ *ap; |
| 445 | { |
| 446 | struct buf *bp; |
| 447 | struct vnode *vp; |
| 448 | struct mount *mp; |
| 449 | |
| 450 | bp = ap->a_bp; |
| 451 | if (((bp->b_flags & B_READ) == 0) && |
| 452 | (LIST_FIRST(&bp->b_dep)) != NULL && bioops.io_start) |
| 453 | (*bioops.io_start)(bp); |
| 454 | |
| 455 | /* |
| 456 | * Collect statistics on synchronous and asynchronous read |
| 457 | * and write counts for disks that have associated filesystems. |
| 458 | */ |
| 459 | vp = ap->a_vp; |
| 460 | if (vn_isdisk(vp, NULL) && (mp = vp->v_specmountpoint) != NULL) { |
| 461 | if ((bp->b_flags & B_READ) == 0) { |
| 462 | if (bp->b_lock.lk_lockholder == LK_KERNPROC) |
| 463 | mp->mnt_stat.f_asyncwrites++; |
| 464 | else |
| 465 | mp->mnt_stat.f_syncwrites++; |
| 466 | } else { |
| 467 | if (bp->b_lock.lk_lockholder == LK_KERNPROC) |
| 468 | mp->mnt_stat.f_asyncreads++; |
| 469 | else |
| 470 | mp->mnt_stat.f_syncreads++; |
| 471 | } |
| 472 | } |
| 473 | KASSERT(devsw(bp->b_dev) != NULL, |
| 474 | ("No devsw on dev %s responsible for buffer %p\n", |
| 475 | devtoname(bp->b_dev), bp)); |
| 476 | KASSERT(devsw(bp->b_dev)->d_strategy != NULL, |
| 477 | ("No strategy on dev %s responsible for buffer %p\n", |
| 478 | devtoname(bp->b_dev), bp)); |
| 479 | BUF_STRATEGY(bp, 0); |
| 480 | return (0); |
| 481 | } |
| 482 | |
| 483 | static int |
| 484 | spec_freeblks(ap) |
| 485 | struct vop_freeblks_args /* { |
| 486 | struct vnode *a_vp; |
| 487 | daddr_t a_addr; |
| 488 | daddr_t a_length; |
| 489 | } */ *ap; |
| 490 | { |
| 491 | struct cdevsw *bsw; |
| 492 | struct buf *bp; |
| 493 | |
| 494 | /* |
| 495 | * XXX: This assumes that strategy does the deed right away. |
| 496 | * XXX: this may not be TRTTD. |
| 497 | */ |
| 498 | bsw = devsw(ap->a_vp->v_rdev); |
| 499 | if ((bsw->d_flags & D_CANFREE) == 0) |
| 500 | return (0); |
| 501 | bp = geteblk(ap->a_length); |
| 502 | bp->b_flags |= B_FREEBUF; |
| 503 | bp->b_dev = ap->a_vp->v_rdev; |
| 504 | bp->b_blkno = ap->a_addr; |
| 505 | bp->b_offset = dbtob(ap->a_addr); |
| 506 | bp->b_bcount = ap->a_length; |
| 507 | BUF_STRATEGY(bp, 0); |
| 508 | return (0); |
| 509 | } |
| 510 | |
| 511 | /* |
| 512 | * Implement degenerate case where the block requested is the block |
| 513 | * returned, and assume that the entire device is contiguous in regards |
| 514 | * to the contiguous block range (runp and runb). |
| 515 | */ |
| 516 | static int |
| 517 | spec_bmap(ap) |
| 518 | struct vop_bmap_args /* { |
| 519 | struct vnode *a_vp; |
| 520 | daddr_t a_bn; |
| 521 | struct vnode **a_vpp; |
| 522 | daddr_t *a_bnp; |
| 523 | int *a_runp; |
| 524 | int *a_runb; |
| 525 | } */ *ap; |
| 526 | { |
| 527 | struct vnode *vp = ap->a_vp; |
| 528 | int runp = 0; |
| 529 | int runb = 0; |
| 530 | |
| 531 | if (ap->a_vpp != NULL) |
| 532 | *ap->a_vpp = vp; |
| 533 | if (ap->a_bnp != NULL) |
| 534 | *ap->a_bnp = ap->a_bn; |
| 535 | if (vp->v_mount != NULL) |
| 536 | runp = runb = MAXBSIZE / vp->v_mount->mnt_stat.f_iosize; |
| 537 | if (ap->a_runp != NULL) |
| 538 | *ap->a_runp = runp; |
| 539 | if (ap->a_runb != NULL) |
| 540 | *ap->a_runb = runb; |
| 541 | return (0); |
| 542 | } |
| 543 | |
| 544 | /* |
| 545 | * Device close routine |
| 546 | */ |
| 547 | /* ARGSUSED */ |
| 548 | static int |
| 549 | spec_close(ap) |
| 550 | struct vop_close_args /* { |
| 551 | struct vnode *a_vp; |
| 552 | int a_fflag; |
| 553 | struct ucred *a_cred; |
| 554 | struct proc *a_p; |
| 555 | } */ *ap; |
| 556 | { |
| 557 | struct vnode *vp = ap->a_vp; |
| 558 | struct proc *p = ap->a_p; |
| 559 | dev_t dev = vp->v_rdev; |
| 560 | |
| 561 | /* |
| 562 | * Hack: a tty device that is a controlling terminal |
| 563 | * has a reference from the session structure. |
| 564 | * We cannot easily tell that a character device is |
| 565 | * a controlling terminal, unless it is the closing |
| 566 | * process' controlling terminal. In that case, |
| 567 | * if the reference count is 2 (this last descriptor |
| 568 | * plus the session), release the reference from the session. |
| 569 | */ |
| 570 | if (vcount(vp) == 2 && p && (vp->v_flag & VXLOCK) == 0 && |
| 571 | vp == p->p_session->s_ttyvp) { |
| 572 | vrele(vp); |
| 573 | p->p_session->s_ttyvp = NULL; |
| 574 | } |
| 575 | /* |
| 576 | * We do not want to really close the device if it |
| 577 | * is still in use unless we are trying to close it |
| 578 | * forcibly. Since every use (buffer, vnode, swap, cmap) |
| 579 | * holds a reference to the vnode, and because we mark |
| 580 | * any other vnodes that alias this device, when the |
| 581 | * sum of the reference counts on all the aliased |
| 582 | * vnodes descends to one, we are on last close. |
| 583 | */ |
| 584 | if (vp->v_flag & VXLOCK) { |
| 585 | /* Forced close */ |
| 586 | } else if (devsw(dev)->d_flags & D_TRACKCLOSE) { |
| 587 | /* Keep device updated on status */ |
| 588 | } else if (vcount(vp) > 1) { |
| 589 | return (0); |
| 590 | } |
| 591 | return (devsw(dev)->d_close(dev, ap->a_fflag, S_IFCHR, p)); |
| 592 | } |
| 593 | |
| 594 | /* |
| 595 | * Print out the contents of a special device vnode. |
| 596 | */ |
| 597 | static int |
| 598 | spec_print(ap) |
| 599 | struct vop_print_args /* { |
| 600 | struct vnode *a_vp; |
| 601 | } */ *ap; |
| 602 | { |
| 603 | |
| 604 | printf("tag VT_NON, dev %s\n", devtoname(ap->a_vp->v_rdev)); |
| 605 | return (0); |
| 606 | } |
| 607 | |
| 608 | /* |
| 609 | * Special device advisory byte-level locks. |
| 610 | */ |
| 611 | /* ARGSUSED */ |
| 612 | static int |
| 613 | spec_advlock(ap) |
| 614 | struct vop_advlock_args /* { |
| 615 | struct vnode *a_vp; |
| 616 | caddr_t a_id; |
| 617 | int a_op; |
| 618 | struct flock *a_fl; |
| 619 | int a_flags; |
| 620 | } */ *ap; |
| 621 | { |
| 622 | |
| 623 | return (ap->a_flags & F_FLOCK ? EOPNOTSUPP : EINVAL); |
| 624 | } |
| 625 | |
| 626 | static void |
| 627 | spec_getpages_iodone(bp) |
| 628 | struct buf *bp; |
| 629 | { |
| 630 | |
| 631 | bp->b_flags |= B_DONE; |
| 632 | wakeup(bp); |
| 633 | } |
| 634 | |
| 635 | static int |
| 636 | spec_getpages(ap) |
| 637 | struct vop_getpages_args *ap; |
| 638 | { |
| 639 | vm_offset_t kva; |
| 640 | int error; |
| 641 | int i, pcount, size, s; |
| 642 | daddr_t blkno; |
| 643 | struct buf *bp; |
| 644 | vm_page_t m; |
| 645 | vm_ooffset_t offset; |
| 646 | int toff, nextoff, nread; |
| 647 | struct vnode *vp = ap->a_vp; |
| 648 | int blksiz; |
| 649 | int gotreqpage; |
| 650 | |
| 651 | error = 0; |
| 652 | pcount = round_page(ap->a_count) / PAGE_SIZE; |
| 653 | |
| 654 | /* |
| 655 | * Calculate the offset of the transfer and do sanity check. |
| 656 | * FreeBSD currently only supports an 8 TB range due to b_blkno |
| 657 | * being in DEV_BSIZE ( usually 512 ) byte chunks on call to |
| 658 | * VOP_STRATEGY. XXX |
| 659 | */ |
| 660 | offset = IDX_TO_OFF(ap->a_m[0]->pindex) + ap->a_offset; |
| 661 | |
| 662 | #define DADDR_T_BIT (sizeof(daddr_t)*8) |
| 663 | #define OFFSET_MAX ((1LL << (DADDR_T_BIT + DEV_BSHIFT)) - 1) |
| 664 | |
| 665 | if (offset < 0 || offset > OFFSET_MAX) { |
| 666 | /* XXX still no %q in kernel. */ |
| 667 | printf("spec_getpages: preposterous offset 0x%x%08x\n", |
| 668 | (u_int)((u_quad_t)offset >> 32), |
| 669 | (u_int)(offset & 0xffffffff)); |
| 670 | return (VM_PAGER_ERROR); |
| 671 | } |
| 672 | |
| 673 | blkno = btodb(offset); |
| 674 | |
| 675 | /* |
| 676 | * Round up physical size for real devices. We cannot round using |
| 677 | * v_mount's block size data because v_mount has nothing to do with |
| 678 | * the device. i.e. it's usually '/dev'. We need the physical block |
| 679 | * size for the device itself. |
| 680 | * |
| 681 | * We can't use v_specmountpoint because it only exists when the |
| 682 | * block device is mounted. However, we can use v_rdev. |
| 683 | */ |
| 684 | |
| 685 | if (vn_isdisk(vp, NULL)) |
| 686 | blksiz = vp->v_rdev->si_bsize_phys; |
| 687 | else |
| 688 | blksiz = DEV_BSIZE; |
| 689 | |
| 690 | size = (ap->a_count + blksiz - 1) & ~(blksiz - 1); |
| 691 | |
| 692 | bp = getpbuf(NULL); |
| 693 | kva = (vm_offset_t)bp->b_data; |
| 694 | |
| 695 | /* |
| 696 | * Map the pages to be read into the kva. |
| 697 | */ |
| 698 | pmap_qenter(kva, ap->a_m, pcount); |
| 699 | |
| 700 | /* Build a minimal buffer header. */ |
| 701 | bp->b_flags = B_READ | B_CALL; |
| 702 | bp->b_iodone = spec_getpages_iodone; |
| 703 | |
| 704 | /* B_PHYS is not set, but it is nice to fill this in. */ |
| 705 | bp->b_rcred = bp->b_wcred = curproc->p_ucred; |
| 706 | if (bp->b_rcred != NOCRED) |
| 707 | crhold(bp->b_rcred); |
| 708 | if (bp->b_wcred != NOCRED) |
| 709 | crhold(bp->b_wcred); |
| 710 | bp->b_blkno = blkno; |
| 711 | bp->b_lblkno = blkno; |
| 712 | pbgetvp(ap->a_vp, bp); |
| 713 | bp->b_bcount = size; |
| 714 | bp->b_bufsize = size; |
| 715 | bp->b_resid = 0; |
| 716 | bp->b_runningbufspace = bp->b_bufsize; |
| 717 | runningbufspace += bp->b_runningbufspace; |
| 718 | |
| 719 | cnt.v_vnodein++; |
| 720 | cnt.v_vnodepgsin += pcount; |
| 721 | |
| 722 | /* Do the input. */ |
| 723 | VOP_STRATEGY(bp->b_vp, bp); |
| 724 | |
| 725 | s = splbio(); |
| 726 | |
| 727 | /* We definitely need to be at splbio here. */ |
| 728 | while ((bp->b_flags & B_DONE) == 0) |
| 729 | tsleep(bp, PVM, "spread", 0); |
| 730 | |
| 731 | splx(s); |
| 732 | |
| 733 | if ((bp->b_flags & B_ERROR) != 0) { |
| 734 | if (bp->b_error) |
| 735 | error = bp->b_error; |
| 736 | else |
| 737 | error = EIO; |
| 738 | } |
| 739 | |
| 740 | nread = size - bp->b_resid; |
| 741 | |
| 742 | if (nread < ap->a_count) { |
| 743 | bzero((caddr_t)kva + nread, |
| 744 | ap->a_count - nread); |
| 745 | } |
| 746 | pmap_qremove(kva, pcount); |
| 747 | |
| 748 | |
| 749 | gotreqpage = 0; |
| 750 | for (i = 0, toff = 0; i < pcount; i++, toff = nextoff) { |
| 751 | nextoff = toff + PAGE_SIZE; |
| 752 | m = ap->a_m[i]; |
| 753 | |
| 754 | m->flags &= ~PG_ZERO; |
| 755 | |
| 756 | if (nextoff <= nread) { |
| 757 | m->valid = VM_PAGE_BITS_ALL; |
| 758 | vm_page_undirty(m); |
| 759 | } else if (toff < nread) { |
| 760 | /* |
| 761 | * Since this is a VM request, we have to supply the |
| 762 | * unaligned offset to allow vm_page_set_validclean() |
| 763 | * to zero sub-DEV_BSIZE'd portions of the page. |
| 764 | */ |
| 765 | vm_page_set_validclean(m, 0, nread - toff); |
| 766 | } else { |
| 767 | m->valid = 0; |
| 768 | vm_page_undirty(m); |
| 769 | } |
| 770 | |
| 771 | if (i != ap->a_reqpage) { |
| 772 | /* |
| 773 | * Just in case someone was asking for this page we |
| 774 | * now tell them that it is ok to use. |
| 775 | */ |
| 776 | if (!error || (m->valid == VM_PAGE_BITS_ALL)) { |
| 777 | if (m->valid) { |
| 778 | if (m->flags & PG_WANTED) { |
| 779 | vm_page_activate(m); |
| 780 | } else { |
| 781 | vm_page_deactivate(m); |
| 782 | } |
| 783 | vm_page_wakeup(m); |
| 784 | } else { |
| 785 | vm_page_free(m); |
| 786 | } |
| 787 | } else { |
| 788 | vm_page_free(m); |
| 789 | } |
| 790 | } else if (m->valid) { |
| 791 | gotreqpage = 1; |
| 792 | /* |
| 793 | * Since this is a VM request, we need to make the |
| 794 | * entire page presentable by zeroing invalid sections. |
| 795 | */ |
| 796 | if (m->valid != VM_PAGE_BITS_ALL) |
| 797 | vm_page_zero_invalid(m, FALSE); |
| 798 | } |
| 799 | } |
| 800 | if (!gotreqpage) { |
| 801 | m = ap->a_m[ap->a_reqpage]; |
| 802 | printf( |
| 803 | "spec_getpages:(%s) I/O read failure: (error=%d) bp %p vp %p\n", |
| 804 | devtoname(bp->b_dev), error, bp, bp->b_vp); |
| 805 | printf( |
| 806 | " size: %d, resid: %ld, a_count: %d, valid: 0x%x\n", |
| 807 | size, bp->b_resid, ap->a_count, m->valid); |
| 808 | printf( |
| 809 | " nread: %d, reqpage: %d, pindex: %lu, pcount: %d\n", |
| 810 | nread, ap->a_reqpage, (u_long)m->pindex, pcount); |
| 811 | /* |
| 812 | * Free the buffer header back to the swap buffer pool. |
| 813 | */ |
| 814 | relpbuf(bp, NULL); |
| 815 | return VM_PAGER_ERROR; |
| 816 | } |
| 817 | /* |
| 818 | * Free the buffer header back to the swap buffer pool. |
| 819 | */ |
| 820 | relpbuf(bp, NULL); |
| 821 | return VM_PAGER_OK; |
| 822 | } |