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-rw-r--r--perl-install/partition_table/dos.pm146
1 files changed, 133 insertions, 13 deletions
diff --git a/perl-install/partition_table/dos.pm b/perl-install/partition_table/dos.pm
index acbc821f2..5ba3c940f 100644
--- a/perl-install/partition_table/dos.pm
+++ b/perl-install/partition_table/dos.pm
@@ -20,41 +20,161 @@ my $offset = $common::SECTORSIZE - length($magic) - $nb_primary * common::psizeo
sub hasExtended { 1 }
+sub geometry_to_string {
+ my ($geom) = @_;
+ "$geom->{cylinders}/$geom->{heads}/$geom->{sectors}";
+}
+
sub last_usable_sector {
my ($hd) = @_;
#- do not use totalsectors, see gi/docs/Partition-ends-after-end-of-disk.txt for more
$hd->{geom}{sectors} * $hd->{geom}{heads} * $hd->{geom}{cylinders};
}
-sub compute_CHS($$) {
- my ($hd, $e) = @_;
- my @l = qw(cyl head sec);
- @$e{map { "start_$_" } @l} = $e->{start} || $e->{type} ? CHS2rawCHS($hd, sector2CHS($hd, $e->{start})) : (0,0,0);
- @$e{map { "end_$_" } @l} = $e->{start} || $e->{type} ? CHS2rawCHS($hd, sector2CHS($hd, $e->{start} + $e->{size} - 1)) : (0,0,0);
- 1;
+sub get_rawCHS {
+ my ($part) = @_;
+ [ $part->{start_cyl}, $part->{start_head}, $part->{start_sec} ],
+ [ $part->{end_cyl}, $part->{end_head}, $part->{end_sec} ];
+}
+sub set_rawCHS {
+ my ($part, $raw_chs_start, $raw_chs_end) = @_;
+ ($part->{start_cyl}, $part->{start_head}, $part->{start_sec}) = @$raw_chs_start;
+ ($part->{end_cyl}, $part->{end_head}, $part->{end_sec}) = @$raw_chs_end;
+}
+
+sub compute_CHS {
+ my ($hd, $part) = @_;
+ my ($chs_start, $chs_end) = CHS_from_part_linear($hd->{geom}, $part);
+ set_rawCHS($part, $chs_start ? CHS2rawCHS($hd->{geom}, $chs_start) : [0,0,0],
+ $chs_end ? CHS2rawCHS($hd->{geom}, $chs_end) : [0,0,0]);
+}
+
+sub CHS_from_part_rawCHS {
+ my ($part) = @_;
+
+ $part->{start} || $part->{type} or return;
+
+ my ($raw_chs_start, $raw_chs_end) = get_rawCHS($part);
+ rawCHS2CHS($raw_chs_start), rawCHS2CHS($raw_chs_end);
+}
+
+sub CHS_from_part_linear {
+ my ($geom, $part) = @_;
+
+ $part->{start} || $part->{type} or return;
+
+ sector2CHS($geom, $part->{start}), sector2CHS($geom, $part->{start} + $part->{size} - 1);
+}
+
+sub rawCHS2CHS {
+ my ($chs) = @_;
+ my ($c, $h, $s) = @$chs;
+ [ $c | (($s & 0xc0) << 2), $h, ($s & 0x3f) - 1 ];
}
sub CHS2rawCHS {
- my ($hd, $chs) = @_;
+ my ($geom, $chs) = @_;
my ($c, $h, $s) = @$chs;
if ($c > 1023) {
#- no way to have a #cylinder >= 1024
$c = 1023;
- $h = $hd->{geom}{heads} - 1;
- $s = $hd->{geom}{sectors} - 1;
+ $h = $geom->{heads} - 1;
+ $s = $geom->{sectors} - 1;
}
- ($c & 0xff, $h, ($s + 1) | (($c >> 2) & 0xc0));
+ [ $c & 0xff, $h, ($s + 1) | (($c >> 2) & 0xc0) ];
}
# returns (cylinder, head, sector)
sub sector2CHS {
- my ($hd, $start) = @_;
+ my ($geom, $start) = @_;
my ($s, $h);
- ($start, $s) = divide($start, $hd->{geom}{sectors});
- ($start, $h) = divide($start, $hd->{geom}{heads});
+ ($start, $s) = divide($start, $geom->{sectors});
+ ($start, $h) = divide($start, $geom->{heads});
[ $start, $h, $s ];
}
+sub is_geometry_valid_for_the_partition_table {
+ my ($hd, $geom, $no_log) = @_;
+
+ every {
+ my ($chs_start_v1, $chs_end_v1) = map { join(',', @$_) } CHS_from_part_rawCHS($_) or next;
+ my ($chs_start_v2, $chs_end_v2) = map { join(',', @$_) } map { [ min($_->[0], 1023), $_->[1], $_->[2] ] } CHS_from_part_linear($geom, $_);
+ if (!$no_log) {
+ $chs_start_v1 eq $chs_start_v2 or log::l("check_geometry_using_the_partition_table failed for ($_->{device}, $_->{start}): $chs_start_v1 vs $chs_start_v2 with geometry " . geometry_to_string($geom));
+ $chs_end_v1 eq $chs_end_v2 or log::l("check_geometry_using_the_partition_table failed for ($_->{device}, " . ($_->{start} + $_->{size} - 1) . "): $chs_end_v1 vs $chs_end_v2 with geometry " . geometry_to_string($geom));
+ }
+ $chs_start_v1 eq $chs_start_v2 && $chs_end_v1 eq $chs_end_v2;
+ } @{$hd->{primary}{normal} || []};
+}
+
+#- from parted, thanks!
+my @valid_nb_sectors = (63, 61, 48, 32, 16);
+my @valid_nb_heads = (255, 192, 128, 96, 64, 61, 32, 17, 16);
+
+sub guess_geometry_from_partition_table {
+ my ($hd) = @_;
+
+ my @chss = map { CHS_from_part_rawCHS($_) } @{$hd->{primary}{normal} || []} or return { empty => 1 };
+ my ($nb_heads, $nb_sectors) = (max(map { $_->[1] } @chss) + 1, max(map { $_->[2] } @chss) + 1);
+ my $geom = { sectors => $nb_sectors, heads => $nb_heads };
+ partition_table::raw::compute_nb_cylinders($geom, $hd->{totalsectors});
+ log::l("guess_geometry_from_partition_table $hd->{device}: " . geometry_to_string($geom));
+
+ member($geom->{heads}, @valid_nb_heads) && member($geom->{sectors}, @valid_nb_sectors) or return { invalid => 1 };
+ $geom;
+}
+
+sub try_every_geometry {
+ my ($hd) = @_;
+
+ my $geom = {};
+ foreach (@valid_nb_sectors) {
+ $geom->{sectors} = $_;
+ foreach (@valid_nb_heads) {
+ $geom->{heads} = $_;
+ if (is_geometry_valid_for_the_partition_table($hd, $geom, 1)) {
+ partition_table::raw::compute_nb_cylinders($geom, $hd->{totalsectors});
+ log::l("try_every_geometry $hd->{device}: found " . geometry_to_string($geom));
+ return $geom;
+ }
+ }
+ }
+ log::l("$hd->{device}: argh! no geometry exists for this partition table");
+ undef;
+}
+
+sub set_best_geometry_for_the_partition_table {
+ my ($hd) = @_;
+
+ my $guessed_geom = guess_geometry_from_partition_table($hd);
+ if ($guessed_geom->{empty}) {
+ log::l("$hd->{device}: would need looking at BIOS info to find out geometry");
+ return;
+ }
+ if ($guessed_geom->{invalid}) {
+ log::l("$hd->{device}: no valid geometry guessed from partition table");
+ $guessed_geom = try_every_geometry($hd) or return;
+ }
+
+ if ($guessed_geom->{heads} == $hd->{geom}{heads} && $guessed_geom->{sectors} == $hd->{geom}{sectors}) {
+ # cool!
+ } else {
+ my $default_ok = is_geometry_valid_for_the_partition_table($hd, $hd->{geom}, 0);
+ my $guessed_ok = is_geometry_valid_for_the_partition_table($hd, $guessed_geom, 0);
+ if ($default_ok && $guessed_ok) {
+ #- oh my!?
+ log::l("$hd->{device}: both guessed and default are valid??? " . geometry_to_string($hd->{geom}) . " vs " . geometry_to_string($guessed_geom));
+ } elsif ($default_ok) {
+ log::l("$hd->{device}: keeping default geometry " . geometry_to_string($hd->{geom}));
+ } elsif ($guessed_ok) {
+ log::l("$hd->{device}: using guessed geometry " . geometry_to_string($guessed_geom) . " instead of " . geometry_to_string($hd->{geom}));
+ put_in_hash($hd->{geom}, $guessed_geom);
+ } else {
+ log::l("$hd->{device}: argh! no valid geometry found");
+ }
+ }
+}
+
sub read {
my ($hd, $sector) = @_;
my $tmp;