diff options
Diffstat (limited to 'sys/kern/subr_diskmbr.c')
| -rw-r--r-- | sys/kern/subr_diskmbr.c | 445 |
1 files changed, 445 insertions, 0 deletions
diff --git a/sys/kern/subr_diskmbr.c b/sys/kern/subr_diskmbr.c new file mode 100644 index 0000000..adfd39c --- /dev/null +++ b/sys/kern/subr_diskmbr.c @@ -0,0 +1,445 @@ +/*- + * Copyright (c) 1994 Bruce D. Evans. + * All rights reserved. + * + * Copyright (c) 1982, 1986, 1988 Regents of the University of California. + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. All advertising materials mentioning features or use of this software + * must display the following acknowledgement: + * This product includes software developed by the University of + * California, Berkeley and its contributors. + * 4. Neither the name of the University nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + * + * from: @(#)ufs_disksubr.c 7.16 (Berkeley) 5/4/91 + * from: ufs_disksubr.c,v 1.8 1994/06/07 01:21:39 phk Exp $ + * $Id: diskslice_machdep.c,v 1.31 1998/08/10 07:22:14 phk Exp $ + */ + +#include <sys/param.h> +#include <sys/buf.h> +#include <sys/conf.h> +#include <sys/disklabel.h> +#define DOSPTYP_EXTENDED 5 +#define DOSPTYP_EXTENDEDX 15 +#define DOSPTYP_ONTRACK 84 +#include <sys/diskslice.h> +#include <sys/malloc.h> +#include <sys/syslog.h> +#include <sys/systm.h> + +#define TRACE(str) do { if (dsi_debug) printf str; } while (0) + +static volatile u_char dsi_debug; + +static struct dos_partition historical_bogus_partition_table[NDOSPART] = { + { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, }, + { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, }, + { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, }, + { 0x80, 0, 1, 0, DOSPTYP_386BSD, 255, 255, 255, 0, 50000, }, +}; + +static int check_part __P((char *sname, struct dos_partition *dp, + u_long offset, int nsectors, int ntracks, + u_long mbr_offset)); +static void extended __P((char *dname, dev_t dev, d_strategy_t *strat, + struct disklabel *lp, struct diskslices *ssp, + u_long ext_offset, u_long ext_size, + u_long base_ext_offset, int nsectors, int ntracks, + u_long mbr_offset)); + +static int +check_part(sname, dp, offset, nsectors, ntracks, mbr_offset ) + char *sname; + struct dos_partition *dp; + u_long offset; + int nsectors; + int ntracks; + u_long mbr_offset; +{ + int chs_ecyl; + int chs_esect; + int chs_scyl; + int chs_ssect; + int error; + u_long esector; + u_long esector1; + u_long secpercyl; + u_long ssector; + u_long ssector1; + + secpercyl = (u_long)nsectors * ntracks; + chs_scyl = DPCYL(dp->dp_scyl, dp->dp_ssect); + chs_ssect = DPSECT(dp->dp_ssect); + ssector = chs_ssect - 1 + dp->dp_shd * nsectors + chs_scyl * secpercyl + + mbr_offset; + ssector1 = offset + dp->dp_start; + + /* + * If ssector1 is on a cylinder >= 1024, then ssector can't be right. + * Allow the C/H/S for it to be 1023/ntracks-1/nsectors, or correct + * apart from the cylinder being reduced modulo 1024. Always allow + * 1023/255/63. + */ + if (ssector < ssector1 + && ((chs_ssect == nsectors && dp->dp_shd == ntracks - 1 + && chs_scyl == 1023) + || (secpercyl != 0 + && (ssector1 - ssector) % (1024 * secpercyl) == 0)) + || (dp->dp_scyl == 255 && dp->dp_shd == 255 + && dp->dp_ssect == 255)) { + TRACE(("%s: C/H/S start %d/%d/%d, start %lu: allow\n", + sname, chs_scyl, dp->dp_shd, chs_ssect, ssector1)); + ssector = ssector1; + } + + chs_ecyl = DPCYL(dp->dp_ecyl, dp->dp_esect); + chs_esect = DPSECT(dp->dp_esect); + esector = chs_esect - 1 + dp->dp_ehd * nsectors + chs_ecyl * secpercyl + + mbr_offset; + esector1 = ssector1 + dp->dp_size - 1; + + /* Allow certain bogus C/H/S values for esector, as above. */ + if (esector < esector1 + && ((chs_esect == nsectors && dp->dp_ehd == ntracks - 1 + && chs_ecyl == 1023) + || (secpercyl != 0 + && (esector1 - esector) % (1024 * secpercyl) == 0)) + || (dp->dp_ecyl == 255 && dp->dp_ehd == 255 + && dp->dp_esect == 255)) { + TRACE(("%s: C/H/S end %d/%d/%d, end %lu: allow\n", + sname, chs_ecyl, dp->dp_ehd, chs_esect, esector1)); + esector = esector1; + } + + error = (ssector == ssector1 && esector == esector1) ? 0 : EINVAL; + if (bootverbose) + printf("%s: type 0x%x, start %lu, end = %lu, size %lu %s\n", + sname, dp->dp_typ, ssector1, esector1, + (u_long)dp->dp_size, error ? "" : ": OK"); + if (ssector != ssector1 && bootverbose) + printf("%s: C/H/S start %d/%d/%d (%lu) != start %lu: invalid\n", + sname, chs_scyl, dp->dp_shd, chs_ssect, + ssector, ssector1); + if (esector != esector1 && bootverbose) + printf("%s: C/H/S end %d/%d/%d (%lu) != end %lu: invalid\n", + sname, chs_ecyl, dp->dp_ehd, chs_esect, + esector, esector1); + return (error); +} + +int +dsinit(dname, dev, strat, lp, sspp) + char *dname; + dev_t dev; + d_strategy_t *strat; + struct disklabel *lp; + struct diskslices **sspp; +{ + struct buf *bp; + u_char *cp; + int dospart; + struct dos_partition *dp; + struct dos_partition *dp0; + int error; + int max_ncyls; + int max_nsectors; + int max_ntracks; + u_long mbr_offset; + char partname[2]; + u_long secpercyl; + char *sname; + struct diskslice *sp; + struct diskslices *ssp; + + mbr_offset = DOSBBSECTOR; +reread_mbr: + /* Read master boot record. */ + bp = geteblk((int)lp->d_secsize); + bp->b_dev = dkmodpart(dkmodslice(dev, WHOLE_DISK_SLICE), RAW_PART); + bp->b_blkno = mbr_offset; + bp->b_bcount = lp->d_secsize; + bp->b_flags |= B_BUSY | B_READ; + (*strat)(bp); + if (biowait(bp) != 0) { + diskerr(bp, dname, "error reading primary partition table", + LOG_PRINTF, 0, (struct disklabel *)NULL); + printf("\n"); + error = EIO; + goto done; + } + + /* Weakly verify it. */ + cp = bp->b_data; + sname = dsname(dname, dkunit(dev), WHOLE_DISK_SLICE, RAW_PART, + partname); + if (cp[0x1FE] != 0x55 || cp[0x1FF] != 0xAA) { + if (bootverbose) + printf("%s: invalid primary partition table: no magic\n", + sname); + error = EINVAL; + goto done; + } + dp0 = (struct dos_partition *)(cp + DOSPARTOFF); + + /* Check for "Ontrack Diskmanager". */ + for (dospart = 0, dp = dp0; dospart < NDOSPART; dospart++, dp++) { + if (dp->dp_typ == DOSPTYP_ONTRACK) { + if (bootverbose) + printf( + "%s: Found \"Ontrack Disk Manager\" on this disk.\n", sname); + bp->b_flags |= B_INVAL | B_AGE; + brelse(bp); + mbr_offset = 63; + goto reread_mbr; + } + } + + if (bcmp(dp0, historical_bogus_partition_table, + sizeof historical_bogus_partition_table) == 0) { + TRACE(("%s: invalid primary partition table: historical\n", + sname)); + error = EINVAL; + goto done; + } + + /* Guess the geometry. */ + /* + * TODO: + * Perhaps skip entries with 0 size. + * Perhaps only look at entries of type DOSPTYP_386BSD. + */ + max_ncyls = 0; + max_nsectors = 0; + max_ntracks = 0; + for (dospart = 0, dp = dp0; dospart < NDOSPART; dospart++, dp++) { + int ncyls; + int nsectors; + int ntracks; + + ncyls = DPCYL(dp->dp_ecyl, dp->dp_esect) + 1; + if (max_ncyls < ncyls) + max_ncyls = ncyls; + nsectors = DPSECT(dp->dp_esect); + if (max_nsectors < nsectors) + max_nsectors = nsectors; + ntracks = dp->dp_ehd + 1; + if (max_ntracks < ntracks) + max_ntracks = ntracks; + } + + /* + * Check that we have guessed the geometry right by checking the + * partition entries. + */ + /* + * TODO: + * As above. + * Check for overlaps. + * Check against d_secperunit if the latter is reliable. + */ + error = 0; + for (dospart = 0, dp = dp0; dospart < NDOSPART; dospart++, dp++) { + if (dp->dp_scyl == 0 && dp->dp_shd == 0 && dp->dp_ssect == 0 + && dp->dp_start == 0 && dp->dp_size == 0) + continue; + sname = dsname(dname, dkunit(dev), BASE_SLICE + dospart, + RAW_PART, partname); + + /* + * Temporarily ignore errors from this check. We could + * simplify things by accepting the table eariler if we + * always ignore errors here. Perhaps we should always + * accept the table if the magic is right but not let + * bad entries affect the geometry. + */ + check_part(sname, dp, mbr_offset, max_nsectors, max_ntracks, + mbr_offset); + } + if (error != 0) + goto done; + + /* + * Accept the DOS partition table. + * First adjust the label (we have been careful not to change it + * before we can guarantee success). + */ + secpercyl = (u_long)max_nsectors * max_ntracks; + if (secpercyl != 0) { + u_long secperunit; + + lp->d_nsectors = max_nsectors; + lp->d_ntracks = max_ntracks; + lp->d_secpercyl = secpercyl; + secperunit = secpercyl * max_ncyls; + if (lp->d_secperunit < secperunit) + lp->d_secperunit = secperunit; + lp->d_ncylinders = lp->d_secperunit / secpercyl; + } + + /* + * We are passed a pointer to a suitably initialized minimal + * slices "struct" with no dangling pointers in it. Replace it + * by a maximal one. This usually oversizes the "struct", but + * enlarging it while searching for logical drives would be + * inconvenient. + */ + free(*sspp, M_DEVBUF); + ssp = dsmakeslicestruct(MAX_SLICES, lp); + *sspp = ssp; + + /* Initialize normal slices. */ + sp = &ssp->dss_slices[BASE_SLICE]; + for (dospart = 0, dp = dp0; dospart < NDOSPART; dospart++, dp++, sp++) { + sp->ds_offset = mbr_offset + dp->dp_start; + sp->ds_size = dp->dp_size; + sp->ds_type = dp->dp_typ; +#if 0 + lp->d_subtype |= (lp->d_subtype & 3) | dospart + | DSTYPE_INDOSPART; +#endif + } + ssp->dss_nslices = BASE_SLICE + NDOSPART; + + /* Handle extended partitions. */ + sp -= NDOSPART; + for (dospart = 0; dospart < NDOSPART; dospart++, sp++) + if (sp->ds_type == DOSPTYP_EXTENDED || + sp->ds_type == DOSPTYP_EXTENDEDX) + extended(dname, bp->b_dev, strat, lp, ssp, + sp->ds_offset, sp->ds_size, sp->ds_offset, + max_nsectors, max_ntracks, mbr_offset); + +done: + bp->b_flags |= B_INVAL | B_AGE; + brelse(bp); + if (error == EINVAL) + error = 0; + return (error); +} + +void +extended(dname, dev, strat, lp, ssp, ext_offset, ext_size, base_ext_offset, + nsectors, ntracks, mbr_offset) + char *dname; + dev_t dev; + struct disklabel *lp; + d_strategy_t *strat; + struct diskslices *ssp; + u_long ext_offset; + u_long ext_size; + u_long base_ext_offset; + int nsectors; + int ntracks; + u_long mbr_offset; +{ + struct buf *bp; + u_char *cp; + int dospart; + struct dos_partition *dp; + u_long ext_offsets[NDOSPART]; + u_long ext_sizes[NDOSPART]; + char partname[2]; + int slice; + char *sname; + struct diskslice *sp; + + /* Read extended boot record. */ + bp = geteblk((int)lp->d_secsize); + bp->b_dev = dev; + bp->b_blkno = ext_offset; + bp->b_bcount = lp->d_secsize; + bp->b_flags |= B_BUSY | B_READ; + (*strat)(bp); + if (biowait(bp) != 0) { + diskerr(bp, dname, "error reading extended partition table", + LOG_PRINTF, 0, (struct disklabel *)NULL); + printf("\n"); + goto done; + } + + /* Weakly verify it. */ + cp = bp->b_data; + if (cp[0x1FE] != 0x55 || cp[0x1FF] != 0xAA) { + sname = dsname(dname, dkunit(dev), WHOLE_DISK_SLICE, RAW_PART, + partname); + if (bootverbose) + printf("%s: invalid extended partition table: no magic\n", + sname); + goto done; + } + + for (dospart = 0, + dp = (struct dos_partition *)(bp->b_data + DOSPARTOFF), + slice = ssp->dss_nslices, sp = &ssp->dss_slices[slice]; + dospart < NDOSPART; dospart++, dp++) { + ext_sizes[dospart] = 0; + if (dp->dp_scyl == 0 && dp->dp_shd == 0 && dp->dp_ssect == 0 + && dp->dp_start == 0 && dp->dp_size == 0) + continue; + if (dp->dp_typ == DOSPTYP_EXTENDED || + dp->dp_typ == DOSPTYP_EXTENDEDX) { + char buf[32]; + + sname = dsname(dname, dkunit(dev), WHOLE_DISK_SLICE, + RAW_PART, partname); + snprintf(buf, sizeof(buf), "%s", sname); + if (strlen(buf) < sizeof buf - 11) + strcat(buf, "<extended>"); + check_part(buf, dp, base_ext_offset, nsectors, + ntracks, mbr_offset); + ext_offsets[dospart] = base_ext_offset + dp->dp_start; + ext_sizes[dospart] = dp->dp_size; + } else { + sname = dsname(dname, dkunit(dev), slice, RAW_PART, + partname); + check_part(sname, dp, ext_offset, nsectors, ntracks, + mbr_offset); + if (slice >= MAX_SLICES) { + printf("%s: too many slices\n", sname); + slice++; + continue; + } + sp->ds_offset = ext_offset + dp->dp_start; + sp->ds_size = dp->dp_size; + sp->ds_type = dp->dp_typ; + ssp->dss_nslices++; + slice++; + sp++; + } + } + + /* If we found any more slices, recursively find all the subslices. */ + for (dospart = 0; dospart < NDOSPART; dospart++) + if (ext_sizes[dospart] != 0) + extended(dname, dev, strat, lp, ssp, + ext_offsets[dospart], ext_sizes[dospart], + base_ext_offset, nsectors, ntracks, + mbr_offset); + +done: + bp->b_flags |= B_INVAL | B_AGE; + brelse(bp); +} |
