qcow2: Fix metadata preallocation
commitea80b906f445969a5ccc781beb4e8bb7f60bbdbb
authorKevin Wolf <kwolf@redhat.com>
Mon, 31 Aug 2009 10:26:57 +0000 (31 12:26 +0200)
committerAnthony Liguori <aliguori@us.ibm.com>
Wed, 9 Sep 2009 22:31:26 +0000 (9 17:31 -0500)
tree979c101bddb9b7561484c721a6fd301112e60efc
parent3aefa744551f3e9a4ea8776b607e77e99637d2e1
qcow2: Fix metadata preallocation

The wrong version of the preallocation patch has been applied, so this is the
remaining diff.

We can't use truncate to grow the image file to the right size because we don't
know if metadata has been written after the last data cluster. In this case
truncate would shrink the file and destroy its metadata. Write a zero sector at
the end of the virtual disk instead to ensure that the file is big enough.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
block/qcow2.c