package fs::loopback; # $Id: loopback.pm 212860 2005-06-28 09:12:16Z prigaux $ use diagnostics; use strict; #-###################################################################################### #- misc imports #-###################################################################################### use common; use fs::type; use fs; use log; sub check_circular_mounts { my ($part, $all_hds) = @_; my $fstab = [ fs::get::fstab($all_hds), $part ]; # no pb if $part is already in $all_hds my $base_mntpoint = $part->{mntpoint}; my $check; $check = sub { my ($part, @seen) = @_; push @seen, $part->{mntpoint} || return; @seen > 1 && $part->{mntpoint} eq $base_mntpoint and die N("Circular mounts %s\n", join(", ", @seen)); if (my $part = fs::get::up_mount_point($part->{mntpoint}, $fstab)) { #- '/' carrier is a special case, it will be mounted first $check->($part, @seen) if !fs::type::carry_root_loopback($part); } if (isLoopback($part)) { $check->($part->{loopback_device}, @seen); } }; $check->($part) if !($base_mntpoint eq '/' && isLoopback($part)); #- '/' is a special case, no loop check } sub carryRootCreateSymlink { my ($part) = @_; fs::type::carry_root_loopback($part) or return; my $mntpoint = fs::get::mntpoint_prefixed($part); unless (-e $mntpoint) { eval { mkdir_p(dirname($mntpoint)) }; #- do non-relative link for install, should be changed to relative link before rebooting symlink "/initrd/loopfs", $mntpoint; mkdir_p("/initrd/loopfs/lnx4win/boot"); symlink "/initrd/loopfs/lnx4win/boot", "$::prefix/boot"; } #- indicate kernel to keep initrd mkdir_p("$::prefix/initrd"); } sub format_part { my ($part) = @_; fs::mount::part($part->{loopback_device}); create($part); fs::format::part_raw($part, undef); } sub create { my ($part) = @_; my $f = $part->{device} = fs::get::mntpoint_prefixed($part->{loopback_device}) . $part->{loopback_file}; return if -e $f; eval { mkdir_p(dirname($f)) }; log::l("creating loopback file $f ($part->{size} sectors)"); my $block_size = 128; my $s = "\0" x (512 * $block_size); sysopen(my $F, $f, 2 | c::O_CREAT()) or die "failed to create loopback file"; for (my $i = 0; $i < $part->{size}; $i += $block_size) { syswrite $F, $s or die "failed to create loopback file"; } } sub getFree { my ($dir, $part) = @_; my $freespace = $dir ? 2 * (MDK::Common::System::df($dir))[1] : #- df in KiB $part->{size}; $freespace - sum map { $_->{size} } @{$part->{loopback} || []}; } #- returns the size of the loopback file if it already exists #- returns -1 is the loopback file cannot be used sub verifFile { my ($dir, $file, $part) = @_; -e "$dir$file" and return -s "$dir$file"; $_->{loopback_file} eq $file and return -1 foreach @{$part->{loopback} || []}; undef; } sub prepare_boot() { my $r = readlink "$::prefix/boot"; unlink "$::prefix/boot"; mkdir_p("$::prefix/boot"); [$r, $::prefix]; } sub save_boot { my ($loop_boot, $prefix) = @{$_[0]}; $loop_boot or return; my @files = glob_("$prefix/boot/*"); cp_af(@files, $loop_boot) if @files; rm_rf("$prefix/boot"); symlink $loop_boot, "$prefix/boot"; } 1;