Re: [Qemu-devel] Citrix VHD implementation

[Kevin Wolf]

Hi Philipp,

Philipp Schmid schrieb:
> as some of you might know, citrix has open sourced the library they use
> to read and write to VHD disk images.
>
> I'm trying to implementing a block-vhd driver on top of libvhd, but my C
> knowledge is very limited as I haven't written any code in C for a long
> time.

qemu already has a basic driver for VHD images. It's called block-vpc  
and currently works with dynamic disks. If you want to improve VHD  
support in qemu, I think you should start there. It's completely  
synchronous (changing this could be one of the next steps) and small  
enough to be easy to start with.

> Are there any docs about how to implement a block driver for qemu?
> As far as I have seen from the qemu code, block_int.h defines the
> interface and you register your driver in block.c, but that is all I've
> found out so far.

It's more or less all you need. ;-)

Kevin