Serge E. Hallyn
efc8243d00
VHD files technically can be up to 2Tb, but virtual pc is limited to 127G. Currently qemu-img refused to create vpc files > 127G, but it is failing to return error when converting from a non-vpc VHD file which is >127G. It returns success, but creates a truncated converted image. Also, qemu-img info claims the vpc file is 127G (and clean). This patch detects a too-large vpc file and returns -EFBIG. Without this patch, ============================================================= root@ip-10-38-123-242:~/qemu-fixed# qemu-img info /mnt/140g-dynamic.vhd image: /mnt/140g-dynamic.vhd file format: vpc virtual size: 127G (136899993600 bytes) disk size: 284K root@ip-10-38-123-242:~/qemu-fixed# qemu-img convert -f vpc -O raw /mnt/140g-dynamic.vhd /mnt/y root@ip-10-38-123-242:~/qemu-fixed# echo $? 0 root@ip-10-38-123-242:~/qemu-fixed# qemu-img info /mnt/y image: /mnt/y file format: raw virtual size: 127G (136899993600 bytes) disk size: 0 ============================================================= (The 140G image was truncated with no warning or error.) With the patch, I get: ============================================================= root@ip-10-38-123-242:~/qemu-fixed# ./qemu-img info /mnt/140g-dynamic.vhd qemu-img: Could not open '/mnt/140g-dynamic.vhd': File too large root@ip-10-38-123-242:~/qemu-fixed# ./qemu-img convert -f vpc -O raw /mnt/140g-dynamic.vhd /mnt/y qemu-img: Could not open '/mnt/140g-dynamic.vhd': File too large qemu-img: Could not open '/mnt/140g-dynamic.vhd' ============================================================= See https://bugs.launchpad.net/qemu/+bug/814222 for details. Signed-off-by: Serge Hallyn <serge.hallyn@canonical.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Read the documentation in qemu-doc.html. Fabrice Bellard.