vnd.c revision 1.23
1 /* $NetBSD: vnd.c,v 1.23 1996/01/07 22:03:33 thorpej Exp $ */ 2 3 /* 4 * Copyright (c) 1988 University of Utah. 5 * Copyright (c) 1990, 1993 6 * The Regents of the University of California. All rights reserved. 7 * 8 * This code is derived from software contributed to Berkeley by 9 * the Systems Programming Group of the University of Utah Computer 10 * Science Department. 11 * 12 * Redistribution and use in source and binary forms, with or without 13 * modification, are permitted provided that the following conditions 14 * are met: 15 * 1. Redistributions of source code must retain the above copyright 16 * notice, this list of conditions and the following disclaimer. 17 * 2. Redistributions in binary form must reproduce the above copyright 18 * notice, this list of conditions and the following disclaimer in the 19 * documentation and/or other materials provided with the distribution. 20 * 3. All advertising materials mentioning features or use of this software 21 * must display the following acknowledgement: 22 * This product includes software developed by the University of 23 * California, Berkeley and its contributors. 24 * 4. Neither the name of the University nor the names of its contributors 25 * may be used to endorse or promote products derived from this software 26 * without specific prior written permission. 27 * 28 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 29 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 30 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 31 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 32 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 33 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 34 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 35 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 36 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 37 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 38 * SUCH DAMAGE. 39 * 40 * from: Utah $Hdr: vn.c 1.13 94/04/02$ 41 * 42 * @(#)vn.c 8.6 (Berkeley) 4/1/94 43 */ 44 45 /* 46 * Vnode disk driver. 47 * 48 * Block/character interface to a vnode. Allows one to treat a file 49 * as a disk (e.g. build a filesystem in it, mount it, etc.). 50 * 51 * NOTE 1: This uses the VOP_BMAP/VOP_STRATEGY interface to the vnode 52 * instead of a simple VOP_RDWR. We do this to avoid distorting the 53 * local buffer cache. 54 * 55 * NOTE 2: There is a security issue involved with this driver. 56 * Once mounted all access to the contents of the "mapped" file via 57 * the special file is controlled by the permissions on the special 58 * file, the protection of the mapped file is ignored (effectively, 59 * by using root credentials in all transactions). 60 * 61 * NOTE 3: Doesn't interact with leases, should it? 62 */ 63 64 #include <sys/param.h> 65 #include <sys/systm.h> 66 #include <sys/namei.h> 67 #include <sys/proc.h> 68 #include <sys/errno.h> 69 #include <sys/buf.h> 70 #include <sys/malloc.h> 71 #include <sys/ioctl.h> 72 #include <sys/disklabel.h> 73 #include <sys/device.h> 74 #include <sys/disk.h> 75 #include <sys/stat.h> 76 #include <sys/conf.h> 77 #include <sys/mount.h> 78 #include <sys/vnode.h> 79 #include <sys/file.h> 80 #include <sys/uio.h> 81 82 #include <miscfs/specfs/specdev.h> 83 84 #include <dev/vndioctl.h> 85 86 #ifdef DEBUG 87 int dovndcluster = 1; 88 int vnddebug = 0x00; 89 #define VDB_FOLLOW 0x01 90 #define VDB_INIT 0x02 91 #define VDB_IO 0x04 92 #endif 93 94 #define b_cylin b_resid 95 96 #define vndunit(x) DISKUNIT(x) 97 98 struct vndbuf { 99 struct buf vb_buf; 100 struct buf *vb_obp; 101 }; 102 103 #define getvndbuf() \ 104 ((struct vndbuf *)malloc(sizeof(struct vndbuf), M_DEVBUF, M_WAITOK)) 105 #define putvndbuf(vbp) \ 106 free((caddr_t)(vbp), M_DEVBUF) 107 108 struct vnd_softc { 109 int sc_flags; /* flags */ 110 size_t sc_size; /* size of vnd */ 111 struct vnode *sc_vp; /* vnode */ 112 struct ucred *sc_cred; /* credentials */ 113 int sc_maxactive; /* max # of active requests */ 114 struct buf sc_tab; /* transfer queue */ 115 char sc_xname[8]; /* XXX external name */ 116 struct disk sc_dkdev; /* generic disk device info */ 117 }; 118 119 /* sc_flags */ 120 #define VNF_ALIVE 0x01 121 #define VNF_INITED 0x02 122 #define VNF_WANTED 0x40 123 #define VNF_LOCKED 0x80 124 125 struct vnd_softc *vnd_softc; 126 int numvnd = 0; 127 128 /* {b,c}devsw[] function prototypes */ 129 dev_type_open(vndopen); 130 dev_type_close(vndclose); 131 dev_type_strategy(vndstrategy); 132 dev_type_ioctl(vndioctl); 133 dev_type_read(vndread); 134 dev_type_write(vndwrite); 135 136 /* called by main() at boot time */ 137 void vndattach __P((int)); 138 139 void vndclear __P((struct vnd_softc *)); 140 void vndstart __P((struct vnd_softc *)); 141 int vndsetcred __P((struct vnd_softc *, struct ucred *)); 142 void vndthrottle __P((struct vnd_softc *, struct vnode *)); 143 144 static int vndlock __P((struct vnd_softc *)); 145 static void vndunlock __P((struct vnd_softc *)); 146 147 void 148 vndattach(num) 149 int num; 150 { 151 char *mem; 152 register u_long size; 153 154 if (num <= 0) 155 return; 156 size = num * sizeof(struct vnd_softc); 157 mem = malloc(size, M_DEVBUF, M_NOWAIT); 158 if (mem == NULL) { 159 printf("WARNING: no memory for vnode disks\n"); 160 return; 161 } 162 bzero(mem, size); 163 vnd_softc = (struct vnd_softc *)mem; 164 numvnd = num; 165 } 166 167 int 168 vndopen(dev, flags, mode, p) 169 dev_t dev; 170 int flags, mode; 171 struct proc *p; 172 { 173 int unit = vndunit(dev); 174 struct vnd_softc *sc; 175 int error = 0, part, pmask; 176 177 /* 178 * XXX Should support disklabels. 179 */ 180 181 #ifdef DEBUG 182 if (vnddebug & VDB_FOLLOW) 183 printf("vndopen(%x, %x, %x, %x)\n", dev, flags, mode, p); 184 #endif 185 if (unit >= numvnd) 186 return (ENXIO); 187 sc = &vnd_softc[unit]; 188 189 if (error = vndlock(sc)) 190 return (error); 191 192 part = DISKPART(dev); 193 pmask = (1 << part); 194 195 /* Prevent our unit from being unconfigured while open. */ 196 switch (mode) { 197 case S_IFCHR: 198 sc->sc_dkdev.dk_copenmask |= pmask; 199 break; 200 201 case S_IFBLK: 202 sc->sc_dkdev.dk_bopenmask |= pmask; 203 break; 204 } 205 sc->sc_dkdev.dk_openmask = 206 sc->sc_dkdev.dk_copenmask | sc->sc_dkdev.dk_bopenmask; 207 208 vndunlock(sc); 209 return (0); 210 } 211 212 int 213 vndclose(dev, flags, mode, p) 214 dev_t dev; 215 int flags, mode; 216 struct proc *p; 217 { 218 int unit = vndunit(dev); 219 struct vnd_softc *sc; 220 int error = 0, part; 221 222 #ifdef DEBUG 223 if (vnddebug & VDB_FOLLOW) 224 printf("vndclose(%x, %x, %x, %x)\n", dev, flags, mode, p); 225 #endif 226 227 if (unit >= numvnd) 228 return (ENXIO); 229 sc = &vnd_softc[unit]; 230 231 if (error = vndlock(sc)) 232 return (error); 233 234 part = DISKPART(dev); 235 236 /* ...that much closer to allowing unconfiguration... */ 237 switch (mode) { 238 case S_IFCHR: 239 sc->sc_dkdev.dk_copenmask &= ~(1 << part); 240 break; 241 242 case S_IFBLK: 243 sc->sc_dkdev.dk_bopenmask &= ~(1 << part); 244 break; 245 } 246 sc->sc_dkdev.dk_openmask = 247 sc->sc_dkdev.dk_copenmask | sc->sc_dkdev.dk_bopenmask; 248 249 vndunlock(sc); 250 return (0); 251 } 252 253 /* 254 * Break the request into bsize pieces and submit using VOP_BMAP/VOP_STRATEGY. 255 * Note that this driver can only be used for swapping over NFS on the hp 256 * since nfs_strategy on the vax cannot handle u-areas and page tables. 257 */ 258 void 259 vndstrategy(bp) 260 register struct buf *bp; 261 { 262 int unit = vndunit(bp->b_dev); 263 register struct vnd_softc *vnd = &vnd_softc[unit]; 264 register struct vndbuf *nbp; 265 register int bn, bsize, resid; 266 register caddr_t addr; 267 int sz, flags, error; 268 extern void vndiodone(); 269 270 #ifdef DEBUG 271 if (vnddebug & VDB_FOLLOW) 272 printf("vndstrategy(%x): unit %d\n", bp, unit); 273 #endif 274 if ((vnd->sc_flags & VNF_INITED) == 0) { 275 bp->b_error = ENXIO; 276 bp->b_flags |= B_ERROR; 277 biodone(bp); 278 return; 279 } 280 bn = bp->b_blkno; 281 sz = howmany(bp->b_bcount, DEV_BSIZE); 282 bp->b_resid = bp->b_bcount; 283 if (bn < 0 || bn + sz > vnd->sc_size) { 284 if (bn != vnd->sc_size) { 285 bp->b_error = EINVAL; 286 bp->b_flags |= B_ERROR; 287 } 288 biodone(bp); 289 return; 290 } 291 bn = dbtob(bn); 292 bsize = vnd->sc_vp->v_mount->mnt_stat.f_iosize; 293 addr = bp->b_data; 294 flags = bp->b_flags | B_CALL; 295 for (resid = bp->b_resid; resid; resid -= sz) { 296 struct vnode *vp; 297 daddr_t nbn; 298 int off, s, nra; 299 300 nra = 0; 301 VOP_LOCK(vnd->sc_vp); 302 error = VOP_BMAP(vnd->sc_vp, bn / bsize, &vp, &nbn, &nra); 303 VOP_UNLOCK(vnd->sc_vp); 304 if (error == 0 && (long)nbn == -1) 305 error = EIO; 306 #ifdef DEBUG 307 if (!dovndcluster) 308 nra = 0; 309 #endif 310 311 if (off = bn % bsize) 312 sz = bsize - off; 313 else 314 sz = (1 + nra) * bsize; 315 if (resid < sz) 316 sz = resid; 317 #ifdef DEBUG 318 if (vnddebug & VDB_IO) 319 printf("vndstrategy: vp %x/%x bn %x/%x sz %x\n", 320 vnd->sc_vp, vp, bn, nbn, sz); 321 #endif 322 323 nbp = getvndbuf(); 324 nbp->vb_buf.b_flags = flags; 325 nbp->vb_buf.b_bcount = sz; 326 nbp->vb_buf.b_bufsize = bp->b_bufsize; 327 nbp->vb_buf.b_error = 0; 328 if (vp->v_type == VBLK || vp->v_type == VCHR) 329 nbp->vb_buf.b_dev = vp->v_rdev; 330 else 331 nbp->vb_buf.b_dev = NODEV; 332 nbp->vb_buf.b_data = addr; 333 nbp->vb_buf.b_blkno = nbn + btodb(off); 334 nbp->vb_buf.b_proc = bp->b_proc; 335 nbp->vb_buf.b_iodone = vndiodone; 336 nbp->vb_buf.b_vp = vp; 337 nbp->vb_buf.b_rcred = vnd->sc_cred; /* XXX crdup? */ 338 nbp->vb_buf.b_wcred = vnd->sc_cred; /* XXX crdup? */ 339 nbp->vb_buf.b_dirtyoff = bp->b_dirtyoff; 340 nbp->vb_buf.b_dirtyend = bp->b_dirtyend; 341 nbp->vb_buf.b_validoff = bp->b_validoff; 342 nbp->vb_buf.b_validend = bp->b_validend; 343 344 /* save a reference to the old buffer */ 345 nbp->vb_obp = bp; 346 347 /* 348 * If there was an error or a hole in the file...punt. 349 * Note that we deal with this after the nbp allocation. 350 * This ensures that we properly clean up any operations 351 * that we have already fired off. 352 * 353 * XXX we could deal with holes here but it would be 354 * a hassle (in the write case). 355 */ 356 if (error) { 357 nbp->vb_buf.b_error = error; 358 nbp->vb_buf.b_flags |= B_ERROR; 359 bp->b_resid -= (resid - sz); 360 biodone(&nbp->vb_buf); 361 return; 362 } 363 /* 364 * Just sort by block number 365 */ 366 nbp->vb_buf.b_cylin = nbp->vb_buf.b_blkno; 367 s = splbio(); 368 disksort(&vnd->sc_tab, &nbp->vb_buf); 369 if (vnd->sc_tab.b_active < vnd->sc_maxactive) { 370 vnd->sc_tab.b_active++; 371 vndstart(vnd); 372 } 373 splx(s); 374 bn += sz; 375 addr += sz; 376 } 377 } 378 379 /* 380 * Feed requests sequentially. 381 * We do it this way to keep from flooding NFS servers if we are connected 382 * to an NFS file. This places the burden on the client rather than the 383 * server. 384 */ 385 void 386 vndstart(vnd) 387 register struct vnd_softc *vnd; 388 { 389 register struct buf *bp; 390 391 /* 392 * Dequeue now since lower level strategy routine might 393 * queue using same links 394 */ 395 bp = vnd->sc_tab.b_actf; 396 vnd->sc_tab.b_actf = bp->b_actf; 397 #ifdef DEBUG 398 if (vnddebug & VDB_IO) 399 printf("vndstart(%d): bp %x vp %x blkno %x addr %x cnt %x\n", 400 vnd-vnd_softc, bp, bp->b_vp, bp->b_blkno, bp->b_data, 401 bp->b_bcount); 402 #endif 403 404 /* Instrumentation. */ 405 disk_busy(&vnd->sc_dkdev); 406 407 if ((bp->b_flags & B_READ) == 0) 408 bp->b_vp->v_numoutput++; 409 VOP_STRATEGY(bp); 410 } 411 412 void 413 vndiodone(vbp) 414 register struct vndbuf *vbp; 415 { 416 register struct buf *pbp = vbp->vb_obp; 417 register struct vnd_softc *vnd = &vnd_softc[vndunit(pbp->b_dev)]; 418 int s; 419 420 s = splbio(); 421 #ifdef DEBUG 422 if (vnddebug & VDB_IO) 423 printf("vndiodone(%d): vbp %x vp %x blkno %x addr %x cnt %x\n", 424 vnd-vnd_softc, vbp, vbp->vb_buf.b_vp, vbp->vb_buf.b_blkno, 425 vbp->vb_buf.b_data, vbp->vb_buf.b_bcount); 426 #endif 427 428 if (vbp->vb_buf.b_error) { 429 #ifdef DEBUG 430 if (vnddebug & VDB_IO) 431 printf("vndiodone: vbp %x error %d\n", vbp, 432 vbp->vb_buf.b_error); 433 #endif 434 pbp->b_flags |= B_ERROR; 435 pbp->b_error = biowait(&vbp->vb_buf); 436 } 437 pbp->b_resid -= vbp->vb_buf.b_bcount; 438 putvndbuf(vbp); 439 disk_unbusy(&vnd->sc_dkdev, (pbp->b_bcount - pbp->b_resid)); 440 if (pbp->b_resid == 0) { 441 #ifdef DEBUG 442 if (vnddebug & VDB_IO) 443 printf("vndiodone: pbp %x iodone\n", pbp); 444 #endif 445 biodone(pbp); 446 } 447 if (vnd->sc_tab.b_actf) 448 vndstart(vnd); 449 else 450 vnd->sc_tab.b_active--; 451 splx(s); 452 } 453 454 /* ARGSUSED */ 455 int 456 vndread(dev, uio, flags) 457 dev_t dev; 458 struct uio *uio; 459 int flags; 460 { 461 int unit = vndunit(dev); 462 struct vnd_softc *sc; 463 464 #ifdef DEBUG 465 if (vnddebug & VDB_FOLLOW) 466 printf("vndread(%x, %x)\n", dev, uio); 467 #endif 468 469 if (unit >= numvnd) 470 return (ENXIO); 471 sc = &vnd_softc[unit]; 472 473 if ((sc->sc_flags & VNF_INITED) == 0) 474 return (ENXIO); 475 476 return (physio(vndstrategy, NULL, dev, B_READ, minphys, uio)); 477 } 478 479 /* ARGSUSED */ 480 int 481 vndwrite(dev, uio, flags) 482 dev_t dev; 483 struct uio *uio; 484 int flags; 485 { 486 int unit = vndunit(dev); 487 struct vnd_softc *sc; 488 489 #ifdef DEBUG 490 if (vnddebug & VDB_FOLLOW) 491 printf("vndwrite(%x, %x)\n", dev, uio); 492 #endif 493 494 if (unit >= numvnd) 495 return (ENXIO); 496 sc = &vnd_softc[unit]; 497 498 if ((sc->sc_flags & VNF_INITED) == 0) 499 return (ENXIO); 500 501 return (physio(vndstrategy, NULL, dev, B_WRITE, minphys, uio)); 502 } 503 504 /* ARGSUSED */ 505 int 506 vndioctl(dev, cmd, data, flag, p) 507 dev_t dev; 508 u_long cmd; 509 caddr_t data; 510 int flag; 511 struct proc *p; 512 { 513 int unit = vndunit(dev); 514 register struct vnd_softc *vnd; 515 struct vnd_ioctl *vio; 516 struct vattr vattr; 517 struct nameidata nd; 518 int error, part, pmask, s; 519 520 #ifdef DEBUG 521 if (vnddebug & VDB_FOLLOW) 522 printf("vndioctl(%x, %lx, %x, %x, %x): unit %d\n", 523 dev, cmd, data, flag, p, unit); 524 #endif 525 error = suser(p->p_ucred, &p->p_acflag); 526 if (error) 527 return (error); 528 if (unit >= numvnd) 529 return (ENXIO); 530 531 vnd = &vnd_softc[unit]; 532 vio = (struct vnd_ioctl *)data; 533 switch (cmd) { 534 535 case VNDIOCSET: 536 if (vnd->sc_flags & VNF_INITED) 537 return (EBUSY); 538 539 if (error = vndlock(vnd)) 540 return (error); 541 542 /* 543 * Always open for read and write. 544 * This is probably bogus, but it lets vn_open() 545 * weed out directories, sockets, etc. so we don't 546 * have to worry about them. 547 */ 548 NDINIT(&nd, LOOKUP, FOLLOW, UIO_USERSPACE, vio->vnd_file, p); 549 if (error = vn_open(&nd, FREAD|FWRITE, 0)) { 550 vndunlock(vnd); 551 return(error); 552 } 553 if (error = VOP_GETATTR(nd.ni_vp, &vattr, p->p_ucred, p)) { 554 VOP_UNLOCK(nd.ni_vp); 555 (void) vn_close(nd.ni_vp, FREAD|FWRITE, p->p_ucred, p); 556 vndunlock(vnd); 557 return(error); 558 } 559 VOP_UNLOCK(nd.ni_vp); 560 vnd->sc_vp = nd.ni_vp; 561 vnd->sc_size = btodb(vattr.va_size); /* note truncation */ 562 if (error = vndsetcred(vnd, p->p_ucred)) { 563 (void) vn_close(nd.ni_vp, FREAD|FWRITE, p->p_ucred, p); 564 vndunlock(vnd); 565 return(error); 566 } 567 vndthrottle(vnd, vnd->sc_vp); 568 vio->vnd_size = dbtob(vnd->sc_size); 569 vnd->sc_flags |= VNF_INITED; 570 #ifdef DEBUG 571 if (vnddebug & VDB_INIT) 572 printf("vndioctl: SET vp %x size %x\n", 573 vnd->sc_vp, vnd->sc_size); 574 #endif 575 576 /* Attach the disk. */ 577 bzero(vnd->sc_xname, sizeof(vnd->sc_xname)); /* XXX */ 578 sprintf(vnd->sc_xname, "vnd%d", unit); /* XXX */ 579 vnd->sc_dkdev.dk_name = vnd->sc_xname; 580 disk_attach(&vnd->sc_dkdev); 581 582 vndunlock(vnd); 583 584 break; 585 586 case VNDIOCCLR: 587 if ((vnd->sc_flags & VNF_INITED) == 0) 588 return (ENXIO); 589 590 if (error = vndlock(vnd)) 591 return (error); 592 593 /* 594 * Don't unconfigure if any other partitions are open 595 * or if both the character and block flavors of this 596 * partition are open. 597 */ 598 part = DISKPART(dev); 599 pmask = (1 << part); 600 if ((vnd->sc_dkdev.dk_openmask & ~pmask) || 601 ((vnd->sc_dkdev.dk_bopenmask & pmask) && 602 (vnd->sc_dkdev.dk_copenmask & pmask))) { 603 vndunlock(vnd); 604 return (EBUSY); 605 } 606 607 vndclear(vnd); 608 #ifdef DEBUG 609 if (vnddebug & VDB_INIT) 610 printf("vndioctl: CLRed\n"); 611 #endif 612 613 /* Detatch the disk. */ 614 disk_detatch(&vnd->sc_dkdev); 615 616 /* This must be atomic. */ 617 s = splhigh(); 618 vndunlock(vnd); 619 bzero(vnd, sizeof(struct vnd_softc)); 620 splx(s); 621 622 break; 623 624 /* 625 * XXX Should support disklabels. 626 */ 627 628 default: 629 return(ENOTTY); 630 } 631 632 return (0); 633 } 634 635 /* 636 * Duplicate the current processes' credentials. Since we are called only 637 * as the result of a SET ioctl and only root can do that, any future access 638 * to this "disk" is essentially as root. Note that credentials may change 639 * if some other uid can write directly to the mapped file (NFS). 640 */ 641 int 642 vndsetcred(vnd, cred) 643 register struct vnd_softc *vnd; 644 struct ucred *cred; 645 { 646 struct uio auio; 647 struct iovec aiov; 648 char *tmpbuf; 649 int error; 650 651 vnd->sc_cred = crdup(cred); 652 tmpbuf = malloc(DEV_BSIZE, M_TEMP, M_WAITOK); 653 654 /* XXX: Horrible kludge to establish credentials for NFS */ 655 aiov.iov_base = tmpbuf; 656 aiov.iov_len = min(DEV_BSIZE, dbtob(vnd->sc_size)); 657 auio.uio_iov = &aiov; 658 auio.uio_iovcnt = 1; 659 auio.uio_offset = 0; 660 auio.uio_rw = UIO_READ; 661 auio.uio_segflg = UIO_SYSSPACE; 662 auio.uio_resid = aiov.iov_len; 663 VOP_LOCK(vnd->sc_vp); 664 error = VOP_READ(vnd->sc_vp, &auio, 0, vnd->sc_cred); 665 VOP_UNLOCK(vnd->sc_vp); 666 667 free(tmpbuf, M_TEMP); 668 return (error); 669 } 670 671 /* 672 * Set maxactive based on FS type 673 */ 674 void 675 vndthrottle(vnd, vp) 676 register struct vnd_softc *vnd; 677 struct vnode *vp; 678 { 679 #ifdef NFSCLIENT 680 extern int (**nfsv2_vnodeop_p)(); 681 682 if (vp->v_op == nfsv2_vnodeop_p) 683 vnd->sc_maxactive = 2; 684 else 685 #endif 686 vnd->sc_maxactive = 8; 687 688 if (vnd->sc_maxactive < 1) 689 vnd->sc_maxactive = 1; 690 } 691 692 void 693 vndshutdown() 694 { 695 register struct vnd_softc *vnd; 696 697 for (vnd = &vnd_softc[0]; vnd < &vnd_softc[numvnd]; vnd++) 698 if (vnd->sc_flags & VNF_INITED) 699 vndclear(vnd); 700 } 701 702 void 703 vndclear(vnd) 704 register struct vnd_softc *vnd; 705 { 706 register struct vnode *vp = vnd->sc_vp; 707 struct proc *p = curproc; /* XXX */ 708 709 #ifdef DEBUG 710 if (vnddebug & VDB_FOLLOW) 711 printf("vndclear(%x): vp %x\n", vp); 712 #endif 713 vnd->sc_flags &= ~VNF_INITED; 714 if (vp == (struct vnode *)0) 715 panic("vndioctl: null vp"); 716 (void) vn_close(vp, FREAD|FWRITE, vnd->sc_cred, p); 717 crfree(vnd->sc_cred); 718 vnd->sc_vp = (struct vnode *)0; 719 vnd->sc_cred = (struct ucred *)0; 720 vnd->sc_size = 0; 721 } 722 723 int 724 vndsize(dev) 725 dev_t dev; 726 { 727 int unit = vndunit(dev); 728 register struct vnd_softc *vnd = &vnd_softc[unit]; 729 730 if (unit >= numvnd || (vnd->sc_flags & VNF_INITED) == 0) 731 return(-1); 732 return(vnd->sc_size); 733 } 734 735 int 736 vnddump(dev, blkno, va, size) 737 dev_t dev; 738 daddr_t blkno; 739 caddr_t va; 740 size_t size; 741 { 742 743 /* Not implemented. */ 744 return ENXIO; 745 } 746 747 /* 748 * Wait interruptibly for an exclusive lock. 749 * 750 * XXX 751 * Several drivers do this; it should be abstracted and made MP-safe. 752 */ 753 static int 754 vndlock(sc) 755 struct vnd_softc *sc; 756 { 757 int error; 758 759 while ((sc->sc_flags & VNF_LOCKED) != 0) { 760 sc->sc_flags |= VNF_WANTED; 761 if ((error = tsleep(sc, PRIBIO | PCATCH, "vndlck", 0)) != 0) 762 return (error); 763 } 764 sc->sc_flags |= VNF_LOCKED; 765 return (0); 766 } 767 768 /* 769 * Unlock and wake up any waiters. 770 */ 771 static void 772 vndunlock(sc) 773 struct vnd_softc *sc; 774 { 775 776 sc->sc_flags &= ~VNF_LOCKED; 777 if ((sc->sc_flags & VNF_WANTED) != 0) { 778 sc->sc_flags &= ~VNF_WANTED; 779 wakeup(sc); 780 } 781 } 782
Indexes created Tue Sep 30 06:09:59 GMT 2025