X-Git-Url: http://git.annexia.org/?p=libguestfs.git;a=blobdiff_plain;f=tools%2Fvirt-df;h=6ec1c1a723cb07bee1ee1f8b9785def9db16e338;hp=790dd6a11f6eda5b67c600d8ea8a44073b7e9aba;hb=4838ec3326d2970e6afe3cde6b368aeae840b969;hpb=45a4cd79215752234c4a5a47fb4c9c6741b1594c diff --git a/tools/virt-df b/tools/virt-df index 790dd6a..6ec1c1a 100755 --- a/tools/virt-df +++ b/tools/virt-df @@ -1,6 +1,6 @@ #!/usr/bin/perl -w # virt-df -# Copyright (C) 2009 Red Hat Inc. +# Copyright (C) 2009-2010 Red Hat Inc. # # This program is free software; you can redistribute it and/or modify # it under the terms of the GNU General Public License as published by @@ -112,6 +112,23 @@ read L below. =cut +my $format; + +=item B<--format> raw + +Specify the format of disk images given on the command line. If this +is omitted then the format is autodetected from the content of the +disk image. + +If disk images are requested from libvirt, then this program asks +libvirt for this information. In this case, the value of the format +parameter is ignored. + +If working with untrusted raw-format guest disk images, you should +ensure the format is always specified. + +=cut + my $human; =item B<--human-readable> | B<-h> @@ -128,6 +145,48 @@ my $inodes; Print inodes instead of blocks. +=cut + +my $one_per_guest; + +=item B<--one-per-guest> + +Run one libguestfs appliance per guest. Normally C will +add the disks from several guests to a single libguestfs appliance. + +You might use this option in the following circumstances: + +=over 4 + +=item * + +If you think an untrusted guest might actively try to exploit the +libguestfs appliance kernel, then this prevents one guest from +interfering with the stats printed for another guest. + +=item * + +If the kernel has a bug which stops it from accessing a +filesystem in one guest (see for example RHBZ#635373) then +this allows libguestfs to continue and report stats for further +guests. + +=back + +=cut + +my $uuid; + +=item B<--uuid> + +Print UUIDs instead of names. This is useful for following +a guest even when the guest is migrated or renamed, or when +two guests happen to have the same name. + +Note that only domains that we fetch from libvirt come with UUIDs. +For disk images, we still print the disk image name even when +this option is specified. + =back =cut @@ -136,8 +195,11 @@ GetOptions ("help|?" => \$help, "version" => \$version, "connect|c=s" => \$uri, "csv" => \$csv, + "format=s" => \$format, "human-readable|human|h" => \$human, "inodes|i" => \$inodes, + "one-per-guest" => \$one_per_guest, + "uuid" => \$uuid, ) or pod2usage (2); pod2usage (1) if $help; if ($version) { @@ -150,6 +212,15 @@ if ($version) { # RHBZ#600977 die __"virt-df: cannot use -h and --csv options together\n" if $human && $csv; +# RHBZ#635373 +# +# Limit the number of devices we will ever add to the appliance. The +# overall limit in current libguestfs is 25: 26 = number of letters in +# the English alphabet since we are only confident that /dev/sd[a-z] +# will work because of various limits, minus 1 because that may be +# used by the ext2 initial filesystem. +my $max_disks = 25; + # Get the list of domains and block devices. # # We can't use Sys::Guestfs::Lib::open_guest here because we want to @@ -186,12 +257,13 @@ if (@ARGV == 0) { # No params, use libvirt. my @disks = get_disks_from_libvirt ($dom); push @domains, { dom => $dom, name => $dom->get_name (), + uuid => $dom->get_uuid_string (), disks => \@disks } } } elsif (@ARGV == 1) { # One param, could be disk image or domname. if (-e $ARGV[0]) { push @domains, { name => basename ($ARGV[0]), - disks => [ $ARGV[0] ] } + disks => [ [ $ARGV[0], $format ] ] } } else { my $conn; @@ -207,11 +279,13 @@ if (@ARGV == 0) { # No params, use libvirt. my @disks = get_disks_from_libvirt ($dom); push @domains, { dom => $dom, name => $dom->get_name (), + uuid => $dom->get_uuid_string (), disks => \@disks } } } else { # >= 2 params, all disk images. + my @disks = map { [ $_, $format ] } @ARGV; push @domains, { name => basename ($ARGV[0]), - disks => \@ARGV } + disks => \@disks } } sub get_disks_from_libvirt @@ -220,12 +294,29 @@ sub get_disks_from_libvirt my $xml = $dom->get_xml_description (); my $p = XML::XPath->new (xml => $xml); - my @disks = $p->findnodes ('//devices/disk/source/@dev'); - push (@disks, $p->findnodes ('//devices/disk/source/@file')); + my $nodes = $p->find ('//devices/disk'); + + my @disks; + my $node; + foreach $node ($nodes->get_nodelist) { + # The filename can be in dev or file attribute, hence: + my $filename = $p->find ('./source/@dev', $node); + unless ($filename) { + $filename = $p->find ('./source/@file', $node); + next unless $filename; + } + $filename = $filename->to_literal; + + # Get the disk format (may not be set). + my $format = $p->find ('./driver/@type', $node); + $format = $format->to_literal if $format; + + push @disks, [ $filename, $format ]; + } # Code in Sys::Guestfs::Lib dies here if there are no disks at all. - return map { $_->getData } @disks; + return @disks; } # Sort the domains by name for display. @@ -236,66 +327,88 @@ sub get_disks_from_libvirt print_title (); # To minimize the number of times we have to launch the appliance, -# shuffle as many domains together as we can, but not exceeding 26 -# disks per request. (26 = # of letters in the English alphabet, and -# we are only confident that /dev/sd[a-z] will work because of various -# limits). -my $n = 0; -my @request = (); -while (@domains) { +# shuffle as many domains together as we can, but not exceeding +# MAX_DISKS per request. If --one-per-guest was requested then only +# request disks from a single guest each time. +if ($one_per_guest) { + foreach (@domains) { + my @request = ( $_ ); + multi_df (@request); + } +} else { while (@domains) { - my $c = @{$domains[0]->{disks}}; - last if $n + $c > 26; - push @request, shift @domains; + my $n = 0; # number of disks added so far + my @request = (); + while (@domains) { + my $c = @{$domains[0]->{disks}}; + if ($c > $max_disks) { + warn __x("virt-df: ignoring {name}, it has too many disks ({c} > {max})", + name => $domains[0]->{name}, + c => $c, max => $max_disks); + next; + } + last if $n + $c > $max_disks; + $n += $c; + push @request, shift (@domains); + } + multi_df (@request); } - multi_df (@request); } sub multi_df { local $_; - my $g = Sys::Guestfs->new (); - - my ($d, $disk); - - foreach $d (@_) { - foreach $disk (@{$d->{disks}}) { - $g->add_drive_ro ($disk); + eval { + my $g = Sys::Guestfs->new (); + + my ($d, $disk); + + foreach $d (@_) { + foreach $disk (@{$d->{disks}}) { + my $filename = $disk->[0]; + my $format = $disk->[1]; + my @args = ($filename); + push @args, readonly => 1; + push @args, format => $format if defined $format; + $g->add_drive_opts (@args); + } } - } - $g->launch (); - my $has_lvm2 = feature_available ($g, "lvm2"); + $g->launch (); + my $has_lvm2 = feature_available ($g, "lvm2"); - my @devices = $g->list_devices (); - my @partitions = $g->list_partitions (); + my @devices = $g->list_devices (); + my @partitions = $g->list_partitions (); - my $n = 0; - foreach $d (@_) { - my $name = $d->{name}; - my $nr_disks = @{$d->{disks}}; + my $n = 0; + foreach $d (@_) { + my $name = $d->{name}; + my $uuid = $d->{uuid}; + my $nr_disks = @{$d->{disks}}; - # Filter LVM to only the devices applying to the original domain. - my @devs = @devices[$n .. $n+$nr_disks-1]; - $g->lvm_set_filter (\@devs) if $has_lvm2; + # Filter LVM to only the devices applying to the original domain. + my @devs = @devices[$n .. $n+$nr_disks-1]; + $g->lvm_set_filter (\@devs) if $has_lvm2; - # Find which whole devices (RHBZ#590167), partitions and LVs - # contain mountable filesystems. Stat those which are - # mountable, and ignore the others. - foreach (@devs) { - try_df ($name, $g, $_, canonical_dev ($_, $n)); - } - foreach (filter_partitions (\@devs, @partitions)) { - try_df ($name, $g, $_, canonical_dev ($_, $n)); - } - if ($has_lvm2) { - foreach ($g->lvs ()) { - try_df ($name, $g, $_); + # Find which whole devices (RHBZ#590167), partitions and LVs + # contain mountable filesystems. Stat those which are + # mountable, and ignore the others. + foreach (@devs) { + try_df ($name, $uuid, $g, $_, canonical_dev ($_, $n)); + } + foreach (filter_partitions (\@devs, @partitions)) { + try_df ($name, $uuid, $g, $_, canonical_dev ($_, $n)); + } + if ($has_lvm2) { + foreach ($g->lvs ()) { + try_df ($name, $uuid, $g, $_); + } } - } - $n += $nr_disks; - } + $n += $nr_disks; + } + }; + warn if $@; } sub filter_partitions @@ -338,6 +451,7 @@ sub try_df { local $_; my $domname = shift; + my $domuuid = shift; my $g = shift; my $dev = shift; my $display = shift || $dev; @@ -348,7 +462,7 @@ sub try_df %stat = $g->statvfs ("/"); }; if (!$@) { - print_stat ($domname, $display, \%stat); + print_stat ($domname, $domuuid, $display, \%stat); } $g->umount_all (); } @@ -356,10 +470,17 @@ sub try_df sub print_stat { my $domname = shift; + my $domuuid = shift; my $dev = shift; my $stat = shift; - my @cols = ($domname, $dev); + my @cols; + if (!$uuid || !defined $domuuid) { + push @cols, $domname; + } else { + push @cols, $domuuid; + } + push @cols, $dev; if (!$inodes) { my $bsize = $stat->{bsize}; # block size @@ -419,6 +540,7 @@ sub print_title printf "%-36s%10s %10s %10s %5s\n", $cols[1], $cols[2], $cols[3], $cols[4], $cols[5]; } else { + # Columns don't need special CSV quoting. print (join (",", @cols), "\n"); } } @@ -437,7 +559,11 @@ sub print_cols printf ("%10s %10s %10s %5s\n", $_[2], $_[3], $_[4], $percent); } else { - printf ("\"%s\",\"%s\",%d,%d,%d,%.1f%%\n", @_); + # Need to quote libvirt domain and filesystem. + my $dom = shift; + my $fs = shift; + print csv_quote($dom), ",", csv_quote($fs), ","; + printf ("%d,%d,%d,%.1f%%\n", @_); } } @@ -455,6 +581,31 @@ sub human_size } } +# Quote field for CSV without using an external module. +sub csv_quote +{ + local $_ = shift; + + my $needs_quoting = /[ ",\n\0]/; + return $_ unless $needs_quoting; + + my $i; + my $out = '"'; + for ($i = 0; $i < length; ++$i) { + my $c = substr $_, $i, 1; + if ($c eq '"') { + $out .= '""'; + } elsif ($c eq '\0') { + $out .= '"0'; + } else { + $out .= $c; + } + } + $out .= '"'; + + return $out; +} + =head1 NOTE ABOUT CSV FORMAT Comma-separated values (CSV) is a deceptive format. It I like @@ -479,6 +630,13 @@ for Perl or Python's built-in csv library). Most spreadsheets and databases can import CSV directly. +=head1 SHELL QUOTING + +Libvirt guest names can contain arbitrary characters, some of which +have meaning to the shell such as C<#> and space. You may need to +quote or escape these characters on the command line. See the shell +manual page L for details. + =head1 SEE ALSO L,