diff options
Diffstat (limited to 'perl-install/partition_table/dos.pm')
| -rw-r--r-- | perl-install/partition_table/dos.pm | 146 |
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; |