diff options
| -rwxr-xr-x | tools/virt-df | 217 |
1 files changed, 177 insertions, 40 deletions
diff --git a/tools/virt-df b/tools/virt-df index 45b78694..790dd6a1 100755 --- a/tools/virt-df +++ b/tools/virt-df @@ -20,12 +20,11 @@ use warnings; use strict; use Sys::Guestfs; -use Sys::Guestfs::Lib qw(open_guest get_partitions); +use Sys::Guestfs::Lib qw(feature_available); use Pod::Usage; use Getopt::Long; -use Data::Dumper; -use XML::Writer; +use File::Basename qw(basename); use POSIX qw(ceil); use Locale::TextDomain 'libguestfs'; @@ -151,9 +150,22 @@ if ($version) { # RHBZ#600977 die __"virt-df: cannot use -h and --csv options together\n" if $human && $csv; -# Open the guest handle. +# Get the list of domains and block devices. +# +# We can't use Sys::Guestfs::Lib::open_guest here because we want to +# create the libguestfs handle/appliance as few times as possible. +# +# If virt-df is called with no parameters, then run the libvirt +# equivalent of "virsh list --all", get the XML for each domain, and +# get the disk devices. +# +# If virt-df is called with parameters, assume it must either be a +# single disk image filename, a list of disk image filenames, or a +# single libvirt guest name. Construct disk devices accordingly. -if (@ARGV == 0) { +my @domains = (); + +if (@ARGV == 0) { # No params, use libvirt. my $conn; if ($uri) { @@ -168,61 +180,186 @@ if (@ARGV == 0) { # https://bugzilla.redhat.com/show_bug.cgi?id=538041 @doms = grep { $_->get_id () != 0 } @doms; - my @domnames = sort (map { $_->get_name () } @doms); + exit 0 unless @doms; + + foreach my $dom (@doms) { + my @disks = get_disks_from_libvirt ($dom); + push @domains, { dom => $dom, + name => $dom->get_name (), + 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] ] } + } else { + my $conn; - if (@domnames) { - print_title (); - foreach (@domnames) { - eval { do_df ($_); }; - warn $@ if $@; + if ($uri) { + $conn = Sys::Virt->new (readonly => 1, address => $uri); + } else { + $conn = Sys::Virt->new (readonly => 1); } + + my $dom = $conn->get_domain_by_name ($ARGV[0]) + or die __x("{name} is not the name of a libvirt domain\n", + name => $ARGV[0]); + my @disks = get_disks_from_libvirt ($dom); + push @domains, { dom => $dom, + name => $dom->get_name (), + disks => \@disks } } -} else { - print_title (); - do_df (@ARGV); +} else { # >= 2 params, all disk images. + push @domains, { name => basename ($ARGV[0]), + disks => \@ARGV } } -sub do_df +sub get_disks_from_libvirt { - my $g; + my $dom = shift; + my $xml = $dom->get_xml_description (); - if ($uri) { - $g = open_guest (\@_, address => $uri); - } else { - $g = open_guest (\@_); + my $p = XML::XPath->new (xml => $xml); + my @disks = $p->findnodes ('//devices/disk/source/@dev'); + push (@disks, $p->findnodes ('//devices/disk/source/@file')); + + # Code in Sys::Guestfs::Lib dies here if there are no disks at all. + + return map { $_->getData } @disks; +} + +# Sort the domains by name for display. +@domains = sort { $a->{name} cmp $b->{name} } @domains; + +# Since we got this far, we're somewhat sure we're going to +# get to print the result, so display the title. +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) { + while (@domains) { + my $c = @{$domains[0]->{disks}}; + last if $n + $c > 26; + push @request, shift @domains; + } + 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); + } } $g->launch (); + my $has_lvm2 = feature_available ($g, "lvm2"); - my @partitions = get_partitions ($g); - - # Think of a printable name for this domain. Just choose the - # first parameter passed to this function, which will work for - # most cases (it'll either be the domain name or the first disk - # image name). - my $domname = $_[0]; - - # Mount each partition in turn, and if mountable, do a statvfs on it. - foreach my $partition (@partitions) { - my %stat; - eval { - $g->mount_ro ($partition, "/"); - %stat = $g->statvfs ("/"); - }; - if (!$@) { - print_stat ($domname, $partition, \%stat); + my @devices = $g->list_devices (); + my @partitions = $g->list_partitions (); + + my $n = 0; + foreach $d (@_) { + my $name = $d->{name}; + 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 $has_lvm2; + + # Find which whole devices (RHBZ#590167), partitions and LVs + # contain mountable filesystems. Stat those which are + # mountable, and ignore the others. + foreach (@devs) { + try_df ($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, $_); + } + } + + $n += $nr_disks; + } +} + +sub filter_partitions +{ + my $devs = shift; + my @devs = @$devs; + my @r; + + foreach my $p (@_) { + foreach my $d (@devs) { + if ($p =~ /^$d\d/) { + push @r, $p; + last; + } } - $g->umount_all (); } + + return @r; +} + +# Calculate the canonical name for a device. +# eg: /dev/vdb1 when offset = 1 +# => canonical name is /dev/sda1 +sub canonical_dev +{ + local $_; + my $dev = shift; + my $offset = shift; + + return $dev unless $dev =~ m{^/dev/.d([a-z])(\d*)$}; + my $disk = $1; + my $partnum = $2; + + $disk = chr (ord ($disk) - $offset); + + return "/dev/sd$disk$partnum" +} + +sub try_df +{ + local $_; + my $domname = shift; + my $g = shift; + my $dev = shift; + my $display = shift || $dev; + + my %stat; + eval { + $g->mount_ro ($dev, "/"); + %stat = $g->statvfs ("/"); + }; + if (!$@) { + print_stat ($domname, $display, \%stat); + } + $g->umount_all (); } sub print_stat { my $domname = shift; - my $partition = shift; + my $dev = shift; my $stat = shift; - my @cols = ($domname, $partition); + my @cols = ($domname, $dev); if (!$inodes) { my $bsize = $stat->{bsize}; # block size |