[libvirt] [RFC PATCH 0/5] Support online resizing of block devices.

This patch series introduce new API "virDomainBlockResize" to expose qemu monitor command "block_size", which is for resizing the a block device while the domain is running. The prototype for the new API is: int virDomainBlockResize (virDomainPtr dom, const char *path, unsigned long long size, unsigned int flags) * "@path" is the absolute path of the block device, which can be extraced from domain xml. * The units for "@size" is kilobytes, which might be not quite properly. (qemu HMP uses Megabytes as the default units, QMP uses Bytes as the default units, so it means we need to divice "@size" by 1024 for HMP, and multiply "@size" by 1024 for QMP. On the other hand, we need to check the overflowing). Any ideas on this is welcomed. * "@flags" is unused currently. [PATCH 1/5] block_resize: Define the new API [PATCH 2/5] block_resize: Wire up the remote protocol [PATCH 3/5] block_resize: Implement qemu monitor functions [PATCH 4/5] block_resize: Implement qemu driver method [PATCH 5/5] block_resize: Expose the new API to virsh