sys/kern/subr_diskslice.c

   1 /*-
   2  * Copyright (c) 1994 Bruce D. Evans.
   3  * All rights reserved.
   4  *
   5  * Copyright (c) 1990 The Regents of the University of California.
   6  * All rights reserved.
   7  *
   8  * This code is derived from software contributed to Berkeley by
   9  * William Jolitz.
  10  *
  11  * Copyright (c) 1982, 1986, 1988 Regents of the University of California.
  12  * All rights reserved.
  13  *
  14  * Redistribution and use in source and binary forms, with or without
  15  * modification, are permitted provided that the following conditions
  16  * are met:
  17  * 1. Redistributions of source code must retain the above copyright
  18  *    notice, this list of conditions and the following disclaimer.
  19  * 2. Redistributions in binary form must reproduce the above copyright
  20  *    notice, this list of conditions and the following disclaimer in the
  21  *    documentation and/or other materials provided with the distribution.
  22  * 3. Neither the name of the University nor the names of its contributors
  23  *    may be used to endorse or promote products derived from this software
  24  *    without specific prior written permission.
  25  *
  26  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  27  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  28  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  29  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  30  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  31  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  32  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  33  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  34  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  35  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  36  * SUCH DAMAGE.
  37  *
  38  *      from: @(#)wd.c  7.2 (Berkeley) 5/9/91
  39  *      from: wd.c,v 1.55 1994/10/22 01:57:12 phk Exp $
  40  *      from: @(#)ufs_disksubr.c        7.16 (Berkeley) 5/4/91
  41  *      from: ufs_disksubr.c,v 1.8 1994/06/07 01:21:39 phk Exp $
  42  * $FreeBSD: src/sys/kern/subr_diskslice.c,v 1.82.2.6 2001/07/24 09:49:41 dd Exp $
  43  */
  44
  45 #include <sys/param.h>
  46 #include <sys/systm.h>
  47 #include <sys/buf.h>
  48 #include <sys/conf.h>
  49 #include <sys/disklabel.h>
  50 #include <sys/disklabel32.h>
  51 #include <sys/disklabel64.h>
  52 #include <sys/diskslice.h>
  53 #include <sys/disk.h>
  54 #include <sys/diskmbr.h>
  55 #include <sys/fcntl.h>
  56 #include <sys/malloc.h>
  57 #include <sys/stat.h>
  58 #include <sys/syslog.h>
  59 #include <sys/proc.h>
  60 #include <sys/vnode.h>
  61 #include <sys/device.h>
  62 #include <sys/thread2.h>
  63
  64 #include <vfs/ufs/dinode.h>     /* XXX used only for fs.h */
  65 #include <vfs/ufs/fs.h>         /* XXX used only to get BBSIZE/SBSIZE */
  66 #include <sys/devfs.h>
  67
  68 static int  dsreadandsetlabel(cdev_t dev, u_int flags,
  69                            struct diskslices *ssp, struct diskslice *sp,
  70                            struct disk_info *info);
  71 static void free_ds_label (struct diskslices *ssp, int slice);
  72 static void set_ds_label (struct diskslices *ssp, int slice, disklabel_t lp,
  73                            disklabel_ops_t ops);
  74 static void set_ds_wlabel (struct diskslices *ssp, int slice, int wlabel);
  75
  76 /*
  77  * Determine the size of the transfer, and make sure it is
  78  * within the boundaries of the partition. Adjust transfer
  79  * if needed, and signal errors or early completion.
  80  *
  81  * XXX TODO:
  82  *      o Split buffers that are too big for the device.
  83  *      o Check for overflow.
  84  *      o Finish cleaning this up.
  85  *
  86  * This function returns 1 on success, 0 if transfer equates
  87  * to EOF (end of disk) or -1 on failure.  The appropriate
  88  * 'errno' value is also set in bp->b_error and bp->b_flags
  89  * is marked with B_ERROR.
  90  */
  91 struct bio *
  92 dscheck(cdev_t dev, struct bio *bio, struct diskslices *ssp)
  93 {
  94         struct buf *bp = bio->bio_buf;
  95         struct bio *nbio;
  96         disklabel_t lp;
  97         disklabel_ops_t ops;
  98         long nsec;
  99         u_int64_t secno;
 100         u_int64_t endsecno;
 101         u_int64_t slicerel_secno;
 102         struct diskslice *sp;
 103         u_int32_t part;
 104         u_int32_t slice;
 105         int shift;
 106         int mask;
 107
 108         slice = dkslice(dev);
 109         part  = dkpart(dev);
 110
 111         if (bio->bio_offset < 0) {
 112                 kprintf("dscheck(%s): negative bio_offset %lld\n",
 113                         devtoname(dev), (long long)bio->bio_offset);
 114                 goto bad;
 115         }
 116         if (slice >= ssp->dss_nslices) {
 117                 kprintf("dscheck(%s): slice too large %d/%d\n",
 118                         devtoname(dev), slice, ssp->dss_nslices);
 119                 goto bad;
 120         }
 121         sp = &ssp->dss_slices[slice];
 122         /*
 123          * Calculate secno and nsec
 124          */
 125         if (ssp->dss_secmult == 1) {
 126                 shift = DEV_BSHIFT;
 127                 goto doshift;
 128         } else if (ssp->dss_secshift != -1) {
 129                 shift = DEV_BSHIFT + ssp->dss_secshift;
 130 doshift:
 131                 mask = (1 << shift) - 1;
 132                 if ((int)bp->b_bcount & mask)
 133                         goto bad_bcount;
 134                 if ((int)bio->bio_offset & mask)
 135                         goto bad_blkno;
 136                 secno = bio->bio_offset >> shift;
 137                 nsec = bp->b_bcount >> shift;
 138         } else {
 139                 if (bp->b_bcount % ssp->dss_secsize)
 140                         goto bad_bcount;
 141                 if (bio->bio_offset % ssp->dss_secsize)
 142                         goto bad_blkno;
 143                 secno = bio->bio_offset / ssp->dss_secsize;
 144                 nsec = bp->b_bcount / ssp->dss_secsize;
 145         }
 146
 147         /*
 148          * Calculate slice-relative sector number end slice-relative
 149          * limit.
 150          */
 151         if (slice == WHOLE_DISK_SLICE) {
 152                 /*
 153                  * Labels have not been allowed on whole-disks for a while.
 154                  * This really puts the nail in the coffin.
 155                  *
 156                  * Accesses to the WHOLE_DISK_SLICE do not use a disklabel
 157                  * and partition numbers are special-cased.  Currently numbers
 158                  * less then 128 are not allowed.  Partition numbers >= 128
 159                  * are encoded in the high 8 bits of the 64 bit buffer offset
 160                  * and are fed directly through to the device with no
 161                  * further interpretation.  In particular, no sector
 162                  * translation interpretation should occur because the
 163                  * sector size for the special raw access may not be the
 164                  * same as the nominal sector size for the device.
 165                  */
 166                 lp.opaque = NULL;
 167                 if (part < 128) {
 168                         kprintf("dscheck(%s): illegal partition number (%d) "
 169                                 "for WHOLE_DISK_SLICE access\n",
 170                                 devtoname(dev), part);
 171                         goto bad;
 172                 } else if (part != WHOLE_SLICE_PART) {
 173                         nbio = push_bio(bio);
 174                         nbio->bio_offset = bio->bio_offset |
 175                                            (u_int64_t)part << 56;
 176                         return(nbio);
 177                 } else {
 178                         /*
 179                          * If writing to the raw disk request a
 180                          * reprobe on the last close.
 181                          */
 182                         if (bp->b_cmd == BUF_CMD_WRITE)
 183                                 sp->ds_flags |= DSF_REPROBE;
 184                 }
 185
 186                 /*
 187                  * sp->ds_size is for the whole disk in the WHOLE_DISK_SLICE,
 188                  * there are no reserved areas.
 189                  */
 190                 endsecno = sp->ds_size;
 191                 slicerel_secno = secno;
 192         } else if (part == WHOLE_SLICE_PART) {
 193                 /*
 194                  * NOTE! opens on a whole-slice partition will not attempt
 195                  * to read a disklabel in, so there may not be an in-core
 196                  * disklabel even if there is one on the disk.
 197                  */
 198                 endsecno = sp->ds_size;
 199                 slicerel_secno = secno;
 200         } else if ((lp = sp->ds_label).opaque != NULL) {
 201                 /*
 202                  * A label is present, extract the partition.  Snooping of
 203                  * the disklabel is not supported even if accessible.  Of
 204                  * course, the reserved area is still write protected.
 205                  */
 206                 ops = sp->ds_ops;
 207                 if (ops->op_getpartbounds(ssp, lp, part,
 208                                           &slicerel_secno, &endsecno)) {
 209                         kprintf("dscheck(%s): partition %d out of bounds\n",
 210                                 devtoname(dev), part);
 211                         goto bad;
 212                 }
 213                 slicerel_secno += secno;
 214         } else {
 215                 /*
 216                  * Attempt to access partition when no disklabel present
 217                  */
 218                 kprintf("dscheck(%s): attempt to access non-existent partition\n",
 219                         devtoname(dev));
 220                 goto bad;
 221         }
 222
 223         /*
 224          * Disallow writes to reserved areas unless ds_wlabel allows it.
 225          * If the reserved area is written to request a reprobe of the
 226          * disklabel when the slice is closed.
 227          */
 228         if (slicerel_secno < sp->ds_reserved && nsec &&
 229             bp->b_cmd == BUF_CMD_WRITE) {
 230                 if (sp->ds_wlabel == 0) {
 231                         bp->b_error = EROFS;
 232                         goto error;
 233                 }
 234                 sp->ds_flags |= DSF_REPROBE;
 235         }
 236
 237         /*
 238          * If we get here, bio_offset must be on a block boundary and
 239          * the sector size must be a power of 2.
 240          */
 241         if ((bio->bio_offset & (ssp->dss_secsize - 1)) ||
 242             (ssp->dss_secsize ^ (ssp->dss_secsize - 1)) !=
 243             ((ssp->dss_secsize << 1) - 1)) {
 244                 kprintf("%s: invalid BIO offset, not sector aligned or"
 245                         " invalid sector size (not power of 2) %08llx %d\n",
 246                         devtoname(dev), (long long)bio->bio_offset,
 247                         ssp->dss_secsize);
 248                 goto bad;
 249         }
 250
 251         /*
 252          * EOF handling
 253          */
 254         if (secno + nsec > endsecno) {
 255                 /*
 256                  * Return an error if beyond the end of the disk, or
 257                  * if B_BNOCLIP is set.  Tell the system that we do not
 258                  * need to keep the buffer around.
 259                  */
 260                 if (secno > endsecno || (bp->b_flags & B_BNOCLIP))
 261                         goto bad;
 262
 263                 /*
 264                  * If exactly at end of disk, return an EOF.  Throw away
 265                  * the buffer contents, if any, by setting B_INVAL.
 266                  */
 267                 if (secno == endsecno) {
 268                         bp->b_resid = bp->b_bcount;
 269                         bp->b_flags |= B_INVAL;
 270                         goto done;
 271                 }
 272
 273                 /*
 274                  * Else truncate
 275                  */
 276                 nsec = endsecno - secno;
 277                 bp->b_bcount = nsec * ssp->dss_secsize;
 278         }
 279
 280         nbio = push_bio(bio);
 281         nbio->bio_offset = (off_t)(sp->ds_offset + slicerel_secno) *
 282                            ssp->dss_secsize;
 283         return (nbio);
 284
 285 bad_bcount:
 286         kprintf(
 287         "dscheck(%s): b_bcount %d is not on a sector boundary (ssize %d)\n",
 288             devtoname(dev), bp->b_bcount, ssp->dss_secsize);
 289         goto bad;
 290
 291 bad_blkno:
 292         kprintf(
 293         "dscheck(%s): bio_offset %lld is not on a sector boundary (ssize %d)\n",
 294             devtoname(dev), (long long)bio->bio_offset, ssp->dss_secsize);
 295 bad:
 296         bp->b_error = EINVAL;
 297         /* fall through */
 298 error:
 299         /*
 300          * Terminate the I/O with a ranging error.  Since the buffer is
 301          * either illegal or beyond the file EOF, mark it B_INVAL as well.
 302          */
 303         bp->b_resid = bp->b_bcount;
 304         bp->b_flags |= B_ERROR | B_INVAL;
 305 done:
 306         /*
 307          * Caller must biodone() the originally passed bio if NULL is
 308          * returned.
 309          */
 310         return (NULL);
 311 }
 312
 313 /*
 314  * dsclose() - close a cooked disk slice.
 315  *
 316  * WARNING!  The passed diskslices and related diskslice structures may
 317  *           be invalidated or replaced by this function, callers must
 318  *           reload from the disk structure for continued access.
 319  */
 320 void
 321 dsclose(cdev_t dev, int mode, struct diskslices *ssp)
 322 {
 323         u_int32_t part;
 324         u_int32_t slice;
 325         struct diskslice *sp;
 326
 327         slice = dkslice(dev);
 328         part  = dkpart(dev);
 329         if (slice < ssp->dss_nslices) {
 330                 sp = &ssp->dss_slices[slice];
 331                 dsclrmask(sp, part);
 332                 if (sp->ds_flags & DSF_REPROBE) {
 333                         sp->ds_flags &= ~DSF_REPROBE;
 334                         if (slice == WHOLE_DISK_SLICE) {
 335                                 disk_msg_send_sync(DISK_DISK_REPROBE,
 336                                                    dev->si_disk, NULL);
 337                                 devfs_config();
 338                         } else {
 339                                 disk_msg_send_sync(DISK_SLICE_REPROBE,
 340                                                    dev->si_disk, sp);
 341                                 devfs_config();
 342                         }
 343                         /* ssp and sp may both be invalid after reprobe */
 344                 }
 345         }
 346 }
 347
 348 void
 349 dsgone(struct diskslices **sspp)
 350 {
 351         int slice;
 352         struct diskslices *ssp;
 353
 354         if ((ssp = *sspp) != NULL) {
 355                 for (slice = 0; slice < ssp->dss_nslices; slice++)
 356                         free_ds_label(ssp, slice);
 357                 kfree(ssp, M_DEVBUF);
 358                 *sspp = NULL;
 359         }
 360 }
 361
 362 /*
 363  * For the "write" commands (DIOCSDINFO and DIOCWDINFO), this
 364  * is subject to the same restriction as dsopen().
 365  */
 366 int
 367 dsioctl(cdev_t dev, u_long cmd, caddr_t data, int flags,
 368         struct diskslices **sspp, struct disk_info *info)
 369 {
 370         int error;
 371         disklabel_t lp;
 372         disklabel_t lptmp;
 373         disklabel_ops_t ops;
 374         int old_wlabel;
 375         u_int32_t openmask[DKMAXPARTITIONS/(sizeof(u_int32_t)*8)];
 376         int part;
 377         int slice;
 378         struct diskslice *sp;
 379         struct diskslices *ssp;
 380
 381         slice = dkslice(dev);
 382         part = dkpart(dev);
 383         ssp = *sspp;
 384         if (ssp == NULL)
 385                 return (EINVAL);
 386         if (slice >= ssp->dss_nslices)
 387                 return (EINVAL);
 388         sp = &ssp->dss_slices[slice];
 389         lp = sp->ds_label;
 390         ops = sp->ds_ops;       /* may be NULL if no label */
 391
 392         switch (cmd) {
 393         case DIOCGDVIRGIN32:
 394                 ops = &disklabel32_ops;
 395                 /* fall through */
 396         case DIOCGDVIRGIN64:
 397                 if (cmd != DIOCGDVIRGIN32)
 398                         ops = &disklabel64_ops;
 399                 /*
 400                  * You can only retrieve a virgin disklabel on the whole
 401                  * disk slice or whole-slice partition.
 402                  */
 403                 if (slice != WHOLE_DISK_SLICE &&
 404                     part != WHOLE_SLICE_PART) {
 405                         return(EINVAL);
 406                 }
 407
 408                 lp.opaque = data;
 409                 ops->op_makevirginlabel(lp, ssp, sp, info);
 410                 return (0);
 411
 412         case DIOCGDINFO32:
 413         case DIOCGDINFO64:
 414                 /*
 415                  * You can only retrieve a disklabel on the whole
 416                  * slice partition.
 417                  *
 418                  * We do not support labels directly on whole-disks
 419                  * any more (that is, disks without slices), unless the
 420                  * device driver has asked for a compatible label (e.g.
 421                  * for a CD) to allow booting off of storage that is
 422                  * otherwise unlabeled.
 423                  */
 424                 error = 0;
 425                 if (part != WHOLE_SLICE_PART)
 426                         return(EINVAL);
 427                 if (slice == WHOLE_DISK_SLICE &&
 428                     (info->d_dsflags & DSO_COMPATLABEL) == 0) {
 429                         return (ENODEV);
 430                 }
 431                 if (sp->ds_label.opaque == NULL) {
 432                         error = dsreadandsetlabel(dev, info->d_dsflags,
 433                                                   ssp, sp, info);
 434                         ops = sp->ds_ops;       /* may be NULL */
 435                 }
 436
 437                 /*
 438                  * The type of label we found must match the type of
 439                  * label requested.
 440                  */
 441                 if (error == 0 && IOCPARM_LEN(cmd) != ops->labelsize)
 442                         error = ENOATTR;
 443                 if (error == 0)
 444                         bcopy(sp->ds_label.opaque, data, ops->labelsize);
 445                 return (error);
 446
 447         case DIOCGPART:
 448                 {
 449                         struct partinfo *dpart = (void *)data;
 450
 451                         /*
 452                          * The disk management layer may not have read the
 453                          * disklabel yet because simply opening a slice no
 454                          * longer 'probes' the disk that way.  Be sure we
 455                          * have tried.
 456                          *
 457                          * We ignore any error.
 458                          */
 459                         if (sp->ds_label.opaque == NULL &&
 460                             part == WHOLE_SLICE_PART &&
 461                             slice != WHOLE_DISK_SLICE) {
 462                                 dsreadandsetlabel(dev, info->d_dsflags,
 463                                                   ssp, sp, info);
 464                                 ops = sp->ds_ops;       /* may be NULL */
 465                         }
 466
 467                         bzero(dpart, sizeof(*dpart));
 468                         dpart->media_offset   = (u_int64_t)sp->ds_offset *
 469                                                 info->d_media_blksize;
 470                         dpart->media_size     = (u_int64_t)sp->ds_size *
 471                                                 info->d_media_blksize;
 472                         dpart->media_blocks   = sp->ds_size;
 473                         dpart->media_blksize  = info->d_media_blksize;
 474                         dpart->reserved_blocks= sp->ds_reserved;
 475                         dpart->fstype_uuid = sp->ds_type_uuid;
 476                         dpart->storage_uuid = sp->ds_stor_uuid;
 477
 478                         if (slice != WHOLE_DISK_SLICE &&
 479                             part != WHOLE_SLICE_PART) {
 480                                 u_int64_t start;
 481                                 u_int64_t blocks;
 482                                 if (lp.opaque == NULL)
 483                                         return(EINVAL);
 484                                 if (ops->op_getpartbounds(ssp, lp, part,
 485                                                           &start, &blocks)) {
 486                                         return(EINVAL);
 487                                 }
 488                                 ops->op_loadpartinfo(lp, part, dpart);
 489                                 dpart->media_offset += start *
 490                                                        info->d_media_blksize;
 491                                 dpart->media_size = blocks *
 492                                                     info->d_media_blksize;
 493                                 dpart->media_blocks = blocks;
 494
 495                                 /*
 496                                  * partition starting sector (p_offset)
 497                                  * requires slice's reserved areas to be
 498                                  * adjusted.
 499                                  */
 500                                 if (dpart->reserved_blocks > start)
 501                                         dpart->reserved_blocks -= start;
 502                                 else
 503                                         dpart->reserved_blocks = 0;
 504                         }
 505
 506                         /*
 507                          * Load remaining fields from the info structure
 508                          */
 509                         dpart->d_nheads =       info->d_nheads;
 510                         dpart->d_ncylinders =   info->d_ncylinders;
 511                         dpart->d_secpertrack =  info->d_secpertrack;
 512                         dpart->d_secpercyl =    info->d_secpercyl;
 513                 }
 514                 return (0);
 515
 516         case DIOCGSLICEINFO:
 517                 bcopy(ssp, data, (char *)&ssp->dss_slices[ssp->dss_nslices] -
 518                                  (char *)ssp);
 519                 return (0);
 520
 521         case DIOCSDINFO32:
 522                 ops = &disklabel32_ops;
 523                 /* fall through */
 524         case DIOCSDINFO64:
 525                 if (cmd != DIOCSDINFO32)
 526                         ops = &disklabel64_ops;
 527                 /*
 528                  * You can write a disklabel on the whole disk slice or
 529                  * whole-slice partition.
 530                  */
 531                 if (slice != WHOLE_DISK_SLICE &&
 532                     part != WHOLE_SLICE_PART) {
 533                         return(EINVAL);
 534                 }
 535
 536                 /*
 537                  * We no longer support writing disklabels directly to media
 538                  * without there being a slice.  Keep this as a separate
 539                  * conditional.
 540                  */
 541                 if (slice == WHOLE_DISK_SLICE)
 542                         return (ENODEV);
 543                 if (!(flags & FWRITE))
 544                         return (EBADF);
 545
 546                 /*
 547                  * If an existing label is present it must be the same
 548                  * type as the label being passed by the ioctl.
 549                  */
 550                 if (sp->ds_label.opaque && sp->ds_ops != ops)
 551                         return (ENOATTR);
 552
 553                 /*
 554                  * Create a temporary copy of the existing label
 555                  * (if present) so setdisklabel can compare it against
 556                  * the new label.
 557                  */
 558                 lp.opaque = kmalloc(ops->labelsize, M_DEVBUF, M_WAITOK);
 559                 if (sp->ds_label.opaque == NULL)
 560                         bzero(lp.opaque, ops->labelsize);
 561                 else
 562                         bcopy(sp->ds_label.opaque, lp.opaque, ops->labelsize);
 563                 if (sp->ds_label.opaque == NULL) {
 564                         bzero(openmask, sizeof(openmask));
 565                 } else {
 566                         bcopy(sp->ds_openmask, openmask, sizeof(openmask));
 567                 }
 568                 lptmp.opaque = data;
 569                 error = ops->op_setdisklabel(lp, lptmp, ssp, sp, openmask);
 570                 disk_msg_send_sync(DISK_SLICE_REPROBE, dev->si_disk, sp);
 571                 devfs_config();
 572                 if (error != 0) {
 573                         kfree(lp.opaque, M_DEVBUF);
 574                         return (error);
 575                 }
 576                 free_ds_label(ssp, slice);
 577                 set_ds_label(ssp, slice, lp, ops);
 578                 return (0);
 579
 580         case DIOCSYNCSLICEINFO:
 581                 /*
 582                  * This ioctl can only be done on the whole disk
 583                  */
 584                 if (slice != WHOLE_DISK_SLICE || part != WHOLE_SLICE_PART)
 585                         return (EINVAL);
 586
 587                 if (*(int *)data == 0) {
 588                         for (slice = 0; slice < ssp->dss_nslices; slice++) {
 589                                 struct diskslice *ds = &ssp->dss_slices[slice];
 590
 591                                 switch(dscountmask(ds)) {
 592                                 case 0:
 593                                         break;
 594                                 case 1:
 595                                         if (slice != WHOLE_DISK_SLICE)
 596                                                 return (EBUSY);
 597                                         if (!dschkmask(ds, RAW_PART))
 598                                                 return (EBUSY);
 599                                         break;
 600                                 default:
 601                                         return (EBUSY);
 602                                 }
 603                         }
 604                 }
 605
 606                 disk_msg_send_sync(DISK_DISK_REPROBE, dev->si_disk, NULL);
 607                 devfs_config();
 608                 return 0;
 609
 610         case DIOCWDINFO32:
 611         case DIOCWDINFO64:
 612                 error = dsioctl(dev, ((cmd == DIOCWDINFO32) ?
 613                                         DIOCSDINFO32 : DIOCSDINFO64),
 614                                 data, flags, &ssp, info);
 615                 if (error == 0 && sp->ds_label.opaque == NULL)
 616                         error = EINVAL;
 617                 if (part != WHOLE_SLICE_PART)
 618                         error = EINVAL;
 619                 if (error != 0)
 620                         return (error);
 621
 622                 /*
 623                  * Allow the reserved area to be written, reload ops
 624                  * because the DIOCSDINFO op above may have installed
 625                  * a new label type.
 626                  */
 627                 ops = sp->ds_ops;
 628                 old_wlabel = sp->ds_wlabel;
 629                 set_ds_wlabel(ssp, slice, TRUE);
 630                 error = ops->op_writedisklabel(dev, ssp, sp, sp->ds_label);
 631                 disk_msg_send_sync(DISK_SLICE_REPROBE, dev->si_disk, sp);
 632                 devfs_config();
 633                 set_ds_wlabel(ssp, slice, old_wlabel);
 634                 /* XXX should invalidate in-core label if write failed. */
 635                 return (error);
 636
 637         case DIOCWLABEL:
 638                 if (slice == WHOLE_DISK_SLICE)
 639                         return (ENODEV);
 640                 if (!(flags & FWRITE))
 641                         return (EBADF);
 642                 set_ds_wlabel(ssp, slice, *(int *)data != 0);
 643                 return (0);
 644
 645         default:
 646                 return (ENOIOCTL);
 647         }
 648 }
 649
 650 int
 651 dsisopen(struct diskslices *ssp)
 652 {
 653         int slice;
 654
 655         if (ssp == NULL)
 656                 return (0);
 657         for (slice = 0; slice < ssp->dss_nslices; slice++) {
 658                 if (dscountmask(&ssp->dss_slices[slice]))
 659                         return (1);
 660         }
 661         return (0);
 662 }
 663
 664 /*
 665  * Allocate a slices "struct" and initialize it to contain only an empty
 666  * compatibility slice (pointing to itself), a whole disk slice (covering
 667  * the disk as described by the label), and (nslices - BASE_SLICES) empty
 668  * slices beginning at BASE_SLICE.
 669  *
 670  * Note that the compatibility slice is no longer really a compatibility
 671  * slice.  It is slice 0 if a GPT label is present, and the dangerously
 672  * dedicated slice if no slice table otherwise exists.  Else it is 0-sized.
 673  */
 674 struct diskslices *
 675 dsmakeslicestruct(int nslices, struct disk_info *info)
 676 {
 677         struct diskslice *sp;
 678         struct diskslices *ssp;
 679
 680         ssp = kmalloc(offsetof(struct diskslices, dss_slices) +
 681                      nslices * sizeof *sp, M_DEVBUF, M_WAITOK);
 682         ssp->dss_first_bsd_slice = COMPATIBILITY_SLICE;
 683         ssp->dss_nslices = nslices;
 684         ssp->dss_oflags = 0;
 685
 686         /*
 687          * Figure out if we can use shifts or whether we have to
 688          * use mod/multply to translate byte offsets into sector numbers.
 689          */
 690         if ((info->d_media_blksize ^ (info->d_media_blksize - 1)) ==
 691              (info->d_media_blksize << 1) - 1) {
 692                 ssp->dss_secmult = info->d_media_blksize / DEV_BSIZE;
 693                 if (ssp->dss_secmult & (ssp->dss_secmult - 1))
 694                         ssp->dss_secshift = -1;
 695                 else
 696                         ssp->dss_secshift = ffs(ssp->dss_secmult) - 1;
 697         } else {
 698                 ssp->dss_secmult = 0;
 699                 ssp->dss_secshift = -1;
 700         }
 701         ssp->dss_secsize = info->d_media_blksize;
 702         sp = &ssp->dss_slices[0];
 703         bzero(sp, nslices * sizeof *sp);
 704         sp[WHOLE_DISK_SLICE].ds_size = info->d_media_blocks;
 705         return (ssp);
 706 }
 707
 708 char *
 709 dsname(cdev_t dev, int unit, int slice, int part, char *partname)
 710 {
 711         return dev->si_name;
 712 }
 713
 714 /*
 715  * This should only be called when the unit is inactive and the strategy
 716  * routine should not allow it to become active unless we call it.  Our
 717  * strategy routine must be special to allow activity.
 718  */
 719 int
 720 dsopen(cdev_t dev, int mode, u_int flags,
 721        struct diskslices **sspp, struct disk_info *info)
 722 {
 723         struct diskslice *sp;
 724         struct diskslices *ssp;
 725         int slice;
 726         int part;
 727
 728         ssp = *sspp;
 729         dev->si_bsize_phys = info->d_media_blksize;
 730         slice = dkslice(dev);
 731         part = dkpart(dev);
 732         sp = &ssp->dss_slices[slice];
 733         dssetmask(sp, part);
 734
 735         return 0;
 736 }
 737
 738 /*
 739  * Attempt to read the disklabel.  If successful, store it in sp->ds_label.
 740  *
 741  * If we cannot read the disklabel and DSO_COMPATLABEL is set, we construct
 742  * a fake label covering the whole disk.
 743  */
 744 static
 745 int
 746 dsreadandsetlabel(cdev_t dev, u_int flags,
 747                   struct diskslices *ssp, struct diskslice *sp,
 748                   struct disk_info *info)
 749 {
 750         disklabel_t lp;
 751         disklabel_ops_t ops;
 752         const char *msg;
 753         const char *sname;
 754         char partname[2];
 755         int slice = dkslice(dev);
 756
 757         /*
 758          * Probe the disklabel
 759          */
 760         lp.opaque = NULL;
 761         sname = dsname(dev, dkunit(dev), slice, WHOLE_SLICE_PART, partname);
 762         ops = &disklabel32_ops;
 763         msg = ops->op_readdisklabel(dev, sp, &lp, info);
 764         if (msg && strcmp(msg, "no disk label") == 0) {
 765                 ops = &disklabel64_ops;
 766                 msg = disklabel64_ops.op_readdisklabel(dev, sp, &lp, info);
 767         }
 768
 769         /*
 770          * If we failed and COMPATLABEL is set, create a dummy disklabel.
 771          */
 772         if (msg != NULL && (flags & DSO_COMPATLABEL)) {
 773                 msg = NULL;
 774                 if (sp->ds_size >= 0x100000000ULL)
 775                         ops = &disklabel64_ops;
 776                 else
 777                         ops = &disklabel32_ops;
 778                 lp = ops->op_clone_label(info, sp);
 779         }
 780         if (msg != NULL) {
 781                 if (sp->ds_type == DOSPTYP_386BSD /* XXX */)
 782                         log(LOG_WARNING, "%s: cannot find label (%s)\n",
 783                             sname, msg);
 784                 if (lp.opaque)
 785                         kfree(lp.opaque, M_DEVBUF);
 786         } else {
 787                 set_ds_label(ssp, slice, lp, ops);
 788                 set_ds_wlabel(ssp, slice, FALSE);
 789         }
 790         return (msg ? EINVAL : 0);
 791 }
 792
 793 int64_t
 794 dssize(cdev_t dev, struct diskslices **sspp)
 795 {
 796         disklabel_t lp;
 797         disklabel_ops_t ops;
 798         int part;
 799         int slice;
 800         struct diskslices *ssp;
 801         u_int64_t start;
 802         u_int64_t blocks;
 803
 804         slice = dkslice(dev);
 805         part = dkpart(dev);
 806         ssp = *sspp;
 807         if (ssp == NULL || slice >= ssp->dss_nslices
 808             || !dschkmask(&ssp->dss_slices[slice], part)) {
 809                 if (dev_dopen(dev, FREAD, S_IFCHR, proc0.p_ucred, NULL) != 0)
 810                         return (-1);
 811                 dev_dclose(dev, FREAD, S_IFCHR, NULL);
 812                 ssp = *sspp;
 813         }
 814         lp = ssp->dss_slices[slice].ds_label;
 815         if (part == WHOLE_SLICE_PART) {
 816                 blocks = ssp->dss_slices[slice].ds_size;
 817         } else if (lp.opaque == NULL) {
 818                 blocks = (u_int64_t)-1;
 819         } else {
 820                 ops = ssp->dss_slices[slice].ds_ops;
 821                 if (ops->op_getpartbounds(ssp, lp, part, &start, &blocks))
 822                         return (-1);
 823         }
 824         return ((int64_t)blocks);
 825 }
 826
 827 static void
 828 free_ds_label(struct diskslices *ssp, int slice)
 829 {
 830         struct diskslice *sp;
 831         disklabel_t lp;
 832
 833         sp = &ssp->dss_slices[slice];
 834         lp = sp->ds_label;
 835         if (lp.opaque != NULL) {
 836                 kfree(lp.opaque, M_DEVBUF);
 837                 lp.opaque = NULL;
 838                 set_ds_label(ssp, slice, lp, NULL);
 839         }
 840 }
 841
 842 static void
 843 set_ds_label(struct diskslices *ssp, int slice,
 844              disklabel_t lp, disklabel_ops_t ops)
 845 {
 846         struct diskslice *sp = &ssp->dss_slices[slice];
 847
 848         sp->ds_label = lp;
 849         sp->ds_ops = ops;
 850         if (lp.opaque && slice != WHOLE_DISK_SLICE)
 851                 ops->op_adjust_label_reserved(ssp, slice, sp);
 852         else
 853                 sp->ds_reserved = 0;
 854 }
 855
 856 static void
 857 set_ds_wlabel(struct diskslices *ssp, int slice, int wlabel)
 858 {
 859         ssp->dss_slices[slice].ds_wlabel = wlabel;
 860 }
 861