sys/vfs/udf/udf_vfsops.c

   1 /*-
   2  * Copyright (c) 2001, 2002 Scott Long <scottl@freebsd.org>
   3  * 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  *
  14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  24  * SUCH DAMAGE.
  25  *
  26  * $FreeBSD: src/sys/fs/udf/udf_vfsops.c,v 1.16 2003/11/05 06:56:08 scottl Exp $
  27  * $DragonFly: src/sys/vfs/udf/udf_vfsops.c,v 1.27.4.1 2008/09/25 02:20:56 dillon Exp $
  28  */
  29
  30 /* udf_vfsops.c */
  31 /* Implement the VFS side of things */
  32
  33 /*
  34  * Ok, here's how it goes.  The UDF specs are pretty clear on how each data
  35  * structure is made up, but not very clear on how they relate to each other.
  36  * Here is the skinny... This demostrates a filesystem with one file in the
  37  * root directory.  Subdirectories are treated just as normal files, but they
  38  * have File Id Descriptors of their children as their file data.  As for the
  39  * Anchor Volume Descriptor Pointer, it can exist in two of the following three
  40  * places: sector 256, sector n (the max sector of the disk), or sector
  41  * n - 256.  It's a pretty good bet that one will exist at sector 256 though.
  42  * One caveat is unclosed CD media.  For that, sector 256 cannot be written,
  43  * so the Anchor Volume Descriptor Pointer can exist at sector 512 until the
  44  * media is closed.
  45  *
  46  *  Sector:
  47  *     256:
  48  *       n: Anchor Volume Descriptor Pointer
  49  * n - 256:     |
  50  *              |
  51  *              |-->Main Volume Descriptor Sequence
  52  *                      |       |
  53  *                      |       |
  54  *                      |       |-->Logical Volume Descriptor
  55  *                      |                         |
  56  *                      |-->Partition Descriptor  |
  57  *                              |                 |
  58  *                              |                 |
  59  *                              |-->Fileset Descriptor
  60  *                                      |
  61  *                                      |
  62  *                                      |-->Root Dir File Entry
  63  *                                              |
  64  *                                              |
  65  *                                              |-->File data:
  66  *                                                  File Id Descriptor
  67  *                                                      |
  68  *                                                      |
  69  *                                                      |-->File Entry
  70  *                                                              |
  71  *                                                              |
  72  *                                                              |-->File data
  73  */
  74
  75 #include <sys/types.h>
  76 #include <sys/param.h>
  77 #include <sys/systm.h>
  78 #include <sys/uio.h>
  79 #include <sys/buf.h>
  80 #include <sys/conf.h>
  81 #include <sys/fcntl.h>
  82 #include <sys/module.h>
  83 #include <sys/kernel.h>
  84 #include <sys/malloc.h>
  85 #include <sys/mount.h>
  86 #include <sys/nlookup.h>
  87 #include <sys/proc.h>
  88 #include <sys/queue.h>
  89 #include <sys/vnode.h>
  90
  91 #include <vfs/udf/ecma167-udf.h>
  92 #include <vfs/udf/osta.h>
  93 #include <vfs/udf/udf.h>
  94 #include <vfs/udf/udf_mount.h>
  95
  96 extern struct vop_ops udf_vnode_vops;
  97
  98 MALLOC_DEFINE(M_UDFNODE, "UDF node", "UDF node structure");
  99 MALLOC_DEFINE(M_UDFMOUNT, "UDF mount", "UDF mount structure");
 100 MALLOC_DEFINE(M_UDFFENTRY, "UDF fentry", "UDF file entry structure");
 101
 102 static int udf_mount(struct mount *, char *, caddr_t, struct ucred *);
 103 static int udf_unmount(struct mount *, int);
 104 static int udf_root(struct mount *, struct vnode **);
 105 static int udf_statfs(struct mount *, struct statfs *, struct ucred *);
 106 static int udf_fhtovp(struct mount *, struct vnode *,
 107                                 struct fid *, struct vnode **);
 108 static int udf_vptofh(struct vnode *, struct fid *);
 109
 110 static int udf_find_partmaps(struct udf_mnt *, struct logvol_desc *);
 111
 112 static struct vfsops udf_vfsops = {
 113         .vfs_mount =            udf_mount,
 114         .vfs_unmount =          udf_unmount,
 115         .vfs_root =             udf_root,
 116         .vfs_statfs =           udf_statfs,
 117         .vfs_sync =             vfs_stdsync,
 118         .vfs_vget =             udf_vget,
 119         .vfs_fhtovp =           udf_fhtovp,
 120         .vfs_vptofh =           udf_vptofh
 121 };
 122 VFS_SET(udf_vfsops, udf, VFCF_READONLY);
 123
 124 MODULE_VERSION(udf, 1);
 125
 126 static int udf_mountfs(struct vnode *, struct mount *);
 127
 128 static int
 129 udf_mount(struct mount *mp, char *path, caddr_t data, struct ucred *cred)
 130 {
 131         struct vnode *devvp;    /* vnode of the mount device */
 132         struct udf_args args;
 133         struct udf_mnt *imp = 0;
 134         size_t size;
 135         int error;
 136         struct nlookupdata nd;
 137
 138         if ((mp->mnt_flag & MNT_RDONLY) == 0)
 139                 return (EROFS);
 140
 141         /*
 142          * No root filesystem support.  Probably not a big deal, since the
 143          * bootloader doesn't understand UDF.
 144          */
 145         if (mp->mnt_flag & MNT_ROOTFS)
 146                 return (ENOTSUP);
 147
 148         if ((error = copyin(data, (caddr_t)&args, sizeof(struct udf_args))))
 149                 return(error);
 150
 151         if (mp->mnt_flag & MNT_UPDATE) {
 152                 imp = VFSTOUDFFS(mp);
 153                 if (args.fspec == NULL)
 154                         return(vfs_export(mp, &imp->im_export, &args.export));
 155         }
 156
 157         /* Check that the mount device exists */
 158         devvp = NULL;
 159         error = nlookup_init(&nd, args.fspec, UIO_USERSPACE, NLC_FOLLOW);
 160         if (error == 0)
 161                 error = nlookup(&nd);
 162         if (error == 0)
 163                 error = cache_vref(&nd.nl_nch, nd.nl_cred, &devvp);
 164         nlookup_done(&nd);
 165         if (error)
 166                 return (error);
 167
 168         if (vn_isdisk(devvp, &error) == 0) {
 169                 vrele(devvp);
 170                 return(error);
 171         }
 172
 173         /* Check the access rights on the mount device */
 174         vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY);
 175         error = VOP_ACCESS(devvp, VREAD, cred);
 176         if (error)
 177                 error = suser_cred(cred, 0);
 178         if (error) {
 179                 vput(devvp);
 180                 return(error);
 181         }
 182         vn_unlock(devvp);
 183
 184         if ((error = udf_mountfs(devvp, mp))) {
 185                 vrele(devvp);
 186                 return(error);
 187         }
 188
 189         imp = VFSTOUDFFS(mp);
 190
 191         imp->im_flags = args.flags;
 192
 193         copyinstr(args.fspec, mp->mnt_stat.f_mntfromname, MNAMELEN - 1, &size);
 194         bzero(mp->mnt_stat.f_mntfromname + size, MNAMELEN - size);
 195         udf_statfs(mp, &mp->mnt_stat, cred);
 196         return(0);
 197 }
 198
 199 /*
 200  * Check the descriptor tag for both the correct id and correct checksum.
 201  * Return zero if all is good, EINVAL if not.
 202  */
 203 int
 204 udf_checktag(struct desc_tag *tag, uint16_t id)
 205 {
 206         uint8_t *itag;
 207         uint8_t i, cksum = 0;
 208
 209         itag = (uint8_t *)tag;
 210
 211         if (tag->id != id)
 212                 return(EINVAL);
 213
 214         for (i = 0; i < 15; i++)
 215                 cksum = cksum + itag[i];
 216         cksum = cksum - itag[4];
 217
 218         if (cksum == tag->cksum)
 219                 return(0);
 220
 221         return(EINVAL);
 222 }
 223
 224 static int
 225 udf_mountfs(struct vnode *devvp, struct mount *mp)
 226 {
 227         struct buf *bp = NULL;
 228         struct anchor_vdp avdp;
 229         struct udf_mnt *udfmp = NULL;
 230         struct part_desc *pd;
 231         struct logvol_desc *lvd;
 232         struct fileset_desc *fsd;
 233         struct file_entry *root_fentry;
 234         cdev_t dev;
 235         uint32_t sector, size, mvds_start, mvds_end;
 236         uint32_t fsd_offset = 0;
 237         uint16_t part_num = 0, fsd_part = 0;
 238         int error = EINVAL, needclose = 0;
 239         int logvol_found = 0, part_found = 0, fsd_found = 0;
 240         int bsize;
 241
 242         /*
 243          * Disallow multiple mounts of the same device. Flush the buffer
 244          * cache for the device.
 245          */
 246         if ((error = vfs_mountedon(devvp)))
 247                 return(error);
 248         if (count_udev(devvp->v_umajor, devvp->v_uminor) > 0)
 249                 return(EBUSY);
 250         if ((error = vinvalbuf(devvp, V_SAVE, 0, 0)))
 251                 return(error);
 252
 253         vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY);
 254         error = VOP_OPEN(devvp, FREAD, FSCRED, NULL);
 255         vn_unlock(devvp);
 256         if (error)
 257                 return(error);
 258         needclose = 1;
 259         dev = devvp->v_rdev;
 260
 261         udfmp = kmalloc(sizeof(*udfmp), M_UDFMOUNT, M_WAITOK | M_ZERO);
 262
 263         mp->mnt_data = (qaddr_t)udfmp;
 264         mp->mnt_stat.f_fsid.val[0] = dev2udev(dev);
 265         mp->mnt_stat.f_fsid.val[1] = mp->mnt_vfc->vfc_typenum;
 266         mp->mnt_maxsymlinklen = 0;
 267         mp->mnt_flag |= MNT_LOCAL;
 268         udfmp->im_mountp = mp;
 269         udfmp->im_dev = dev;
 270         udfmp->im_devvp = devvp;
 271
 272         bsize = 2048;   /* XXX Should probe the media for it's size */
 273
 274         /*
 275          * Get the Anchor Volume Descriptor Pointer from sector 256.
 276          * XXX Should also check sector n - 256, n, and 512.
 277          */
 278         sector = 256;
 279         if ((error = bread(devvp, (off_t)sector * bsize, bsize, &bp)) != 0)
 280                 goto bail;
 281         if ((error = udf_checktag((struct desc_tag *)bp->b_data, TAGID_ANCHOR)))
 282                 goto bail;
 283
 284         bcopy(bp->b_data, &avdp, sizeof(struct anchor_vdp));
 285         brelse(bp);
 286         bp = NULL;
 287
 288         /*
 289          * Extract the Partition Descriptor and Logical Volume Descriptor
 290          * from the Volume Descriptor Sequence.
 291          * XXX Should we care about the partition type right now?
 292          * XXX What about multiple partitions?
 293          */
 294         mvds_start = avdp.main_vds_ex.loc;
 295         mvds_end = mvds_start + (avdp.main_vds_ex.len - 1) / bsize;
 296         for (sector = mvds_start; sector < mvds_end; sector++) {
 297                 if ((error = bread(devvp, (off_t)sector * bsize, bsize,
 298                                    &bp)) != 0) {
 299                         kprintf("Can't read sector %d of VDS\n", sector);
 300                         goto bail;
 301                 }
 302                 lvd = (struct logvol_desc *)bp->b_data;
 303                 if (!udf_checktag(&lvd->tag, TAGID_LOGVOL)) {
 304                         udfmp->bsize = lvd->lb_size;
 305                         udfmp->bmask = udfmp->bsize - 1;
 306                         udfmp->bshift = ffs(udfmp->bsize) - 1;
 307                         fsd_part = lvd->_lvd_use.fsd_loc.loc.part_num;
 308                         fsd_offset = lvd->_lvd_use.fsd_loc.loc.lb_num;
 309                         if (udf_find_partmaps(udfmp, lvd))
 310                                 break;
 311                         logvol_found = 1;
 312                 }
 313                 pd = (struct part_desc *)bp->b_data;
 314                 if (!udf_checktag(&pd->tag, TAGID_PARTITION)) {
 315                         part_found = 1;
 316                         part_num = pd->part_num;
 317                         udfmp->part_len = pd->part_len;
 318                         udfmp->part_start = pd->start_loc;
 319                 }
 320
 321                 brelse(bp);
 322                 bp = NULL;
 323                 if ((part_found) && (logvol_found))
 324                         break;
 325         }
 326
 327         if (!part_found || !logvol_found) {
 328                 error = EINVAL;
 329                 goto bail;
 330         }
 331
 332         if (fsd_part != part_num) {
 333                 kprintf("FSD does not lie within the partition!\n");
 334                 error = EINVAL;
 335                 goto bail;
 336         }
 337
 338
 339         /*
 340          * Grab the Fileset Descriptor
 341          * Thanks to Chuck McCrobie <mccrobie@cablespeed.com> for pointing
 342          * me in the right direction here.
 343          */
 344         sector = udfmp->part_start + fsd_offset;
 345         if ((error = RDSECTOR(devvp, sector, udfmp->bsize, &bp)) != 0) {
 346                 kprintf("Cannot read sector %d of FSD\n", sector);
 347                 goto bail;
 348         }
 349         fsd = (struct fileset_desc *)bp->b_data;
 350         if (!udf_checktag(&fsd->tag, TAGID_FSD)) {
 351                 fsd_found = 1;
 352                 bcopy(&fsd->rootdir_icb, &udfmp->root_icb,
 353                       sizeof(struct long_ad));
 354         }
 355
 356         brelse(bp);
 357         bp = NULL;
 358
 359         if (!fsd_found) {
 360                 kprintf("Couldn't find the fsd\n");
 361                 error = EINVAL;
 362                 goto bail;
 363         }
 364
 365         vfs_add_vnodeops(mp, &udf_vnode_vops, &mp->mnt_vn_norm_ops);
 366
 367         /*
 368          * Find the file entry for the root directory.
 369          */
 370         sector = udfmp->root_icb.loc.lb_num + udfmp->part_start;
 371         size = udfmp->root_icb.len;
 372         if ((error = udf_readlblks(udfmp, sector, size, &bp)) != 0) {
 373                 kprintf("Cannot read sector %d\n", sector);
 374                 goto bail;
 375         }
 376
 377         root_fentry = (struct file_entry *)bp->b_data;
 378         if ((error = udf_checktag(&root_fentry->tag, TAGID_FENTRY))) {
 379                 kprintf("Invalid root file entry!\n");
 380                 goto bail;
 381         }
 382
 383         brelse(bp);
 384         bp = NULL;
 385
 386         lwkt_token_init(&udfmp->hash_token);
 387         udfmp->hashtbl = phashinit(UDF_HASHTBLSIZE, M_UDFMOUNT, &udfmp->hashsz);
 388
 389         return(0);
 390
 391 bail:
 392         if (udfmp != NULL)
 393                 kfree(udfmp, M_UDFMOUNT);
 394         if (bp != NULL)
 395                 brelse(bp);
 396         if (needclose)
 397                 VOP_CLOSE(devvp, FREAD);
 398         return(error);
 399 }
 400
 401 static int
 402 udf_unmount(struct mount *mp, int mntflags)
 403 {
 404         struct udf_mnt *udfmp;
 405         int error, flags = 0;
 406
 407         udfmp = VFSTOUDFFS(mp);
 408
 409         if (mntflags & MNT_FORCE)
 410                 flags |= FORCECLOSE;
 411
 412         if ((error = vflush(mp, 0, flags)))
 413                 return (error);
 414
 415         udfmp->im_devvp->v_rdev->si_mountpoint = NULL;
 416         error = VOP_CLOSE(udfmp->im_devvp, FREAD);
 417         vrele(udfmp->im_devvp);
 418
 419         if (udfmp->s_table)
 420                 kfree(udfmp->s_table, M_UDFMOUNT);
 421         if (udfmp->hashtbl)
 422                 kfree(udfmp->hashtbl, M_UDFMOUNT);
 423         kfree(udfmp, M_UDFMOUNT);
 424
 425         mp->mnt_data = (qaddr_t)0;
 426         mp->mnt_flag &= ~MNT_LOCAL;
 427
 428         return (error);
 429 }
 430
 431 static int
 432 udf_root(struct mount *mp, struct vnode **vpp)
 433 {
 434         struct udf_mnt *udfmp;
 435         struct vnode *vp;
 436         ino_t id;
 437         int error;
 438
 439         udfmp = VFSTOUDFFS(mp);
 440
 441         id = udf_getid(&udfmp->root_icb);
 442
 443         error = udf_vget(mp, id, vpp);
 444         if (error)
 445                 return(error);
 446
 447         vp = *vpp;
 448         vp->v_flag |= VROOT;
 449         udfmp->root_vp = vp;
 450
 451         return(0);
 452 }
 453
 454 static int
 455 udf_statfs(struct mount *mp, struct statfs *sbp, struct ucred *cred)
 456 {
 457         struct udf_mnt *udfmp;
 458
 459         udfmp = VFSTOUDFFS(mp);
 460
 461         sbp->f_bsize = udfmp->bsize;
 462         sbp->f_iosize = udfmp->bsize;
 463         sbp->f_blocks = udfmp->part_len;
 464         sbp->f_bfree = 0;
 465         sbp->f_bavail = 0;
 466         sbp->f_files = 0;
 467         sbp->f_ffree = 0;
 468         if (sbp != &mp->mnt_stat) {
 469                 sbp->f_type = mp->mnt_vfc->vfc_typenum;
 470                 bcopy(mp->mnt_stat.f_mntfromname, sbp->f_mntfromname, MNAMELEN);
 471         }
 472
 473         return(0);
 474 }
 475
 476 int
 477 udf_vget(struct mount *mp, ino_t ino, struct vnode **vpp)
 478 {
 479         struct buf *bp;
 480         struct vnode *devvp;
 481         struct udf_mnt *udfmp;
 482         struct thread *td;
 483         struct vnode *vp;
 484         struct udf_node *unode;
 485         struct file_entry *fe;
 486         int error, sector, size;
 487
 488         td = curthread;
 489         udfmp = VFSTOUDFFS(mp);
 490
 491         /* See if we already have this in the cache */
 492         if ((error = udf_hashlookup(udfmp, ino, vpp)) != 0)
 493                 return(error);
 494         if (*vpp != NULL) {
 495                 return(0);
 496         }
 497
 498         /*
 499          * Allocate memory and check the tag id's before grabbing a new
 500          * vnode, since it's hard to roll back if there is a problem.
 501          */
 502         unode = kmalloc(sizeof(*unode), M_UDFNODE, M_WAITOK | M_ZERO);
 503
 504         /*
 505          * Copy in the file entry.  Per the spec, the size can only be 1 block.
 506          */
 507         sector = ino + udfmp->part_start;
 508         devvp = udfmp->im_devvp;
 509         if ((error = RDSECTOR(devvp, sector, udfmp->bsize, &bp)) != 0) {
 510                 kprintf("Cannot read sector %d\n", sector);
 511                 kfree(unode, M_UDFNODE);
 512                 return(error);
 513         }
 514
 515         fe = (struct file_entry *)bp->b_data;
 516         if (udf_checktag(&fe->tag, TAGID_FENTRY)) {
 517                 kprintf("Invalid file entry!\n");
 518                 kfree(unode, M_UDFNODE);
 519                 brelse(bp);
 520                 return(ENOMEM);
 521         }
 522         size = UDF_FENTRY_SIZE + fe->l_ea + fe->l_ad;
 523         unode->fentry = kmalloc(size, M_UDFFENTRY, M_WAITOK | M_ZERO);
 524
 525         bcopy(bp->b_data, unode->fentry, size);
 526
 527         brelse(bp);
 528         bp = NULL;
 529
 530         if ((error = udf_allocv(mp, &vp))) {
 531                 kprintf("Error from udf_allocv\n");
 532                 kfree(unode, M_UDFNODE);
 533                 return(error);
 534         }
 535
 536         unode->i_vnode = vp;
 537         unode->hash_id = ino;
 538         unode->i_devvp = udfmp->im_devvp;
 539         unode->i_dev = udfmp->im_dev;
 540         unode->udfmp = udfmp;
 541         vp->v_data = unode;
 542         vref(udfmp->im_devvp);
 543         udf_hashins(unode);
 544
 545         switch (unode->fentry->icbtag.file_type) {
 546         default:
 547                 vp->v_type = VBAD;
 548                 break;
 549         case 4:
 550                 vp->v_type = VDIR;
 551                 break;
 552         case 5:
 553                 vp->v_type = VREG;
 554                 break;
 555         case 6:
 556                 vp->v_type = VBLK;
 557                 break;
 558         case 7:
 559                 vp->v_type = VCHR;
 560                 break;
 561         case 9:
 562                 vp->v_type = VFIFO;
 563                 break;
 564         case 10:
 565                 vp->v_type = VSOCK;
 566                 break;
 567         case 12:
 568                 vp->v_type = VLNK;
 569                 break;
 570         }
 571         /*
 572          * Locked and refd vnode returned
 573          */
 574         *vpp = vp;
 575
 576         return(0);
 577 }
 578
 579 struct ifid {
 580         u_short ifid_len;
 581         u_short ifid_pad;
 582         int     ifid_ino;
 583         long    ifid_start;
 584 };
 585
 586 static int
 587 udf_fhtovp(struct mount *mp, struct vnode *rootvp,
 588            struct fid *fhp, struct vnode **vpp)
 589 {
 590         struct ifid *ifhp;
 591         struct vnode *nvp;
 592         int error;
 593
 594         ifhp = (struct ifid *)fhp;
 595
 596         if ((error = VFS_VGET(mp, ifhp->ifid_ino, &nvp)) != 0) {
 597                 *vpp = NULLVP;
 598                 return(error);
 599         }
 600
 601         *vpp = nvp;
 602         return(0);
 603 }
 604
 605 static int
 606 udf_vptofh (struct vnode *vp, struct fid *fhp)
 607 {
 608         struct udf_node *node;
 609         struct ifid *ifhp;
 610
 611         node = VTON(vp);
 612         ifhp = (struct ifid *)fhp;
 613         ifhp->ifid_len = sizeof(struct ifid);
 614         ifhp->ifid_ino = node->hash_id;
 615
 616         return(0);
 617 }
 618
 619 static int
 620 udf_find_partmaps(struct udf_mnt *udfmp, struct logvol_desc *lvd)
 621 {
 622         union udf_pmap *pmap;
 623         struct part_map_spare *pms;
 624         struct regid *pmap_id;
 625         struct buf *bp;
 626         unsigned char regid_id[UDF_REGID_ID_SIZE + 1];
 627         int ptype, psize, error;
 628         unsigned int i;
 629
 630         for (i = 0; i < lvd->n_pm; i++) {
 631                 pmap = (union udf_pmap *)&lvd->maps[i * UDF_PMAP_SIZE];
 632                 ptype = pmap->data[0];
 633                 psize = pmap->data[1];
 634                 if (((ptype != 1) && (ptype != 2)) ||
 635                     ((psize != UDF_PMAP_SIZE) && (psize != 6))) {
 636                         kprintf("Invalid partition map found\n");
 637                         return(1);
 638                 }
 639
 640                 if (ptype == 1) {
 641                         /* Type 1 map.  We don't care */
 642                         continue;
 643                 }
 644
 645                 /* Type 2 map.  Gotta find out the details */
 646                 pmap_id = (struct regid *)&pmap->data[4];
 647                 bzero(&regid_id[0], UDF_REGID_ID_SIZE);
 648                 bcopy(&pmap_id->id[0], &regid_id[0], UDF_REGID_ID_SIZE);
 649
 650                 if (bcmp(&regid_id[0], "*UDF Sparable Partition",
 651                     UDF_REGID_ID_SIZE)) {
 652                         kprintf("Unsupported partition map: %s\n", &regid_id[0]);
 653                         return(1);
 654                 }
 655
 656                 pms = &pmap->pms;
 657                 udfmp->s_table = kmalloc(pms->st_size, M_UDFMOUNT,
 658                                         M_WAITOK | M_ZERO);
 659
 660                 /* Calculate the number of sectors per packet. */
 661                 /* XXX Logical or physical? */
 662                 udfmp->p_sectors = pms->packet_len / udfmp->bsize;
 663
 664                 /*
 665                  * XXX If reading the first Sparing Table fails, should look
 666                  * for another table.
 667                  */
 668                 if ((error = udf_readlblks(udfmp, pms->st_loc[0], pms->st_size,
 669                     &bp)) != 0) {
 670                         if (bp)
 671                                 brelse(bp);
 672                         kprintf("Failed to read Sparing Table at sector %d\n",
 673                             pms->st_loc[0]);
 674                         return(error);
 675                 }
 676                 bcopy(bp->b_data, udfmp->s_table, pms->st_size);
 677                 brelse(bp);
 678
 679                 if (udf_checktag(&udfmp->s_table->tag, 0)) {
 680                         kprintf("Invalid sparing table found\n");
 681                         return(EINVAL);
 682                 }
 683
 684                 /* See how many valid entries there are here.  The list is
 685                  * supposed to be sorted. 0xfffffff0 and higher are not valid
 686                  */
 687                 for (i = 0; i < udfmp->s_table->rt_l; i++) {
 688                         udfmp->s_table_entries = i;
 689                         if (udfmp->s_table->entries[i].org >= 0xfffffff0)
 690                                 break;
 691                 }
 692         }
 693
 694         return(0);
 695 }