Am 30.07.2024 um 16:15 hat Alberto Garcia geschrieben: > This tool converts a disk image to qcow2, writing the result directly > to stdout. This can be used for example to send the generated file > over the network. > > This is equivalent to using qemu-img to convert a file to qcow2 and > then writing the result to stdout, with the difference that this tool > does not need to create this temporary qcow2 file and therefore does > not need any additional disk space. > > Implementing this directly in qemu-img is not really an option because > it expects the output file to be seekable and it is also meant to be a > generic tool that supports all combinations of file formats and image > options. Instead, this tool can only produce qcow2 files with the > basic options, without compression, encryption or other features. > > The input file is read twice. The first pass is used to determine > which clusters contain non-zero data and that information is used to > create the qcow2 header, refcount table and blocks, and L1 and L2 > tables. After all that metadata is created then the second pass is > used to write the guest data. > > By default qcow2-to-stdout.py expects the input to be a raw file, but > if qemu-storage-daemon is available then it can also be used to read > images in other formats. Alternatively the user can also run qemu-nbd > or qemu-storage-daemon manually instead. > > Signed-off-by: Alberto Garcia <be...@igalia.com> > Signed-off-by: Madeeha Javed <ja...@igalia.com>
Thanks, applied to the block branch. Kevin
