mirror of
https://gitlab.com/libvirt/libvirt.git
synced 2025-03-20 07:59:00 +00:00
4d34c92947
Technically, we should not be re-probing any file that qemu might be currently writing to. As such, we should cache the backing file chain prior to starting qemu. This patch adds the cache, but does not use it until the next patch. Ultimately, we want to also store the chain in domain XML, so that it is remembered across libvirtd restarts, and so that the only kosher way to modify the backing chain of an offline domain will be through libvirt API calls, but we aren't there yet. So for now, we merely invalidate the cache any time we do a live operation that alters the chain (block-pull, block-commit, external disk snapshot), as well as tear down the cache when the domain is not running. * src/conf/domain_conf.h (_virDomainDiskDef): New field. * src/conf/domain_conf.c (virDomainDiskDefFree): Clean new field. * src/qemu/qemu_domain.h (qemuDomainDetermineDiskChain): New prototype. * src/qemu/qemu_domain.c (qemuDomainDetermineDiskChain): New function. * src/qemu/qemu_driver.c (qemuDomainAttachDeviceDiskLive) (qemuDomainChangeDiskMediaLive): Pre-populate chain. (qemuDomainSnapshotCreateSingleDiskActive): Uncache chain before snapshot. * src/qemu/qemu_process.c (qemuProcessHandleBlockJob): Update chain after block pull.
LibVirt : simple API for virtualization
Libvirt is a C toolkit to interact with the virtualization capabilities
of recent versions of Linux (and other OSes). It is free software
available under the GNU Lesser General Public License. Virtualization of
the Linux Operating System means the ability to run multiple instances of
Operating Systems concurrently on a single hardware system where the basic
resources are driven by a Linux instance. The library aim at providing
long term stable C API initially for the Xen paravirtualization but
should be able to integrate other virtualization mechanisms if needed.
Daniel Veillard <veillard@redhat.com>