Libguestfs - Jun 2010 - [PATCH] RHEV: Pad disk sizes up to a multiple of 1024 bytes

Fixes RHBZ#585144
---
 lib/Sys/VirtV2V/Target/RHEV.pm |   27 +++++++++++++++++++++++----
 1 files changed, 23 insertions(+), 4 deletions(-)

diff --git a/lib/Sys/VirtV2V/Target/RHEV.pm b/lib/Sys/VirtV2V/Target/RHEV.pm
index 9dd9013..6841afc 100644
--- a/lib/Sys/VirtV2V/Target/RHEV.pm
+++ b/lib/Sys/VirtV2V/Target/RHEV.pm
@@ -171,12 +171,16 @@ our %vols_by_path;
 sub _new
 {
     my $class = shift;
-    my ($mountdir, $domainuuid, $size) = @_;
+    my ($mountdir, $domainuuid, $insize) = @_;
 
     my $self = {};
     bless($self, $class);
 
-    $self->{size} = $size;
+    $self->{insize} = $insize;
+    # RHEV needs disks to be a multiple of 512 in size. Additionally, SIZE in
+    # the disk meta file has units of kilobytes. To ensure everything matches
up
+    # exactly, we will pad to to a 1024 byte boundary.
+    $self->{outsize} = ceil($insize/1024) * 1024;
 
     my $imageuuid = Sys::VirtV2V::Target::RHEV::UUIDHelper::get_uuid();
     my $voluuid   = Sys::VirtV2V::Target::RHEV::UUIDHelper::get_uuid();
@@ -206,7 +210,7 @@ sub _get_size
 {
     my $self = shift;
 
-    return $self->{size};
+    return $self->{outsize};
 }
 
 sub _get_imageuuid
@@ -256,6 +260,7 @@ sub open
     my $self = shift;
 
     my $now = $self->{creation};
+    $self->{written} = 0;
 
     $self->{writer} = Sys::VirtV2V::Target::RHEV::NFSHelper->new(sub {
         my $dir = $self->{dir};
@@ -283,7 +288,7 @@ sub open
         print $meta "LEGALITY=LEGAL\n";
         print $meta "MTIME=$now\n";
         print $meta
"POOL_UUID=00000000-0000-0000-0000-000000000000\n";
-        print $meta
"SIZE=".ceil($self->{size}/1024)."\n";
+        print $meta "SIZE=".($self->{outsize} /
1024)."\n";
         print $meta "TYPE=SPARSE\n";
         print $meta "DESCRIPTION=Exported by virt-v2v\n";
         print $meta "EOF\n";
@@ -316,12 +321,25 @@ sub write
         # die() explicitly in case the above didn't
         die("Error writing to helper: $!");
     }
+
+    $self->{written} += length($data);
 }
 
 sub close
 {
     my $self = shift;
 
+    # Check we wrote the full file
+    die(user_message(__x("Didn't write full volume. Expected
{expected} ".
+                         "bytes, wrote {actual} bytes.",
+                         expected => $self->{insize},
+                         actual => $self->{written})))
+        unless ($self->{written} == $self->{insize});
+
+    # Pad the output up to outsize
+    my $pad = $self->{outsize} - $self->{insize};
+    $self->write("\0" x $pad) if ($pad);
+
     # Close the writer pipe, which will cause the child to exit
     close($self->{writer}->{tochild})
         or die("Error closing tochild pipe");
@@ -330,6 +348,7 @@ sub close
     $self->{writer}->check_exit();
 
     delete($self->{writer});
+    delete($self->{written});
 }
 
 package Sys::VirtV2V::Target::RHEV;
-- 
1.7.0.1

On Tue, Jun 01, 2010 at 12:00:28PM +0100, Matthew Booth
wrote:
> Fixes RHBZ#585144
> +    # exactly, we will pad to to a 1024 byte boundary.
> +    $self->{outsize} = ceil($insize/1024) * 1024;
Does this work on a 32 bit machine?  Perl might try to promote
these to floats.

Anyway the fix looks good for 64 bit, so ACK.

Rich.

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
virt-p2v converts physical machines to virtual machines.  Boot with a
live CD or over the network (PXE) and turn machines into Xen guests.
http://et.redhat.com/~rjones/virt-p2v