[PATCH 0/4] qemu: fix block jobs when copy_on_read is enabled
QEMU requires us to pass the topmost node(-name) in the backing chain as
the 'device' argument for the blockdev-mirror/block-commit commands.
Otherwise QEMU complains:
"Need a root block node"
Since libvirt always puts the copy-on-read driver on top of the backing
chain, blockjobs on disks which use "copy_on_read" fail.
The series below fixes that by passing the proper node. This fixes it
just fine for the mirror, but for block-commit we still get another
error due to a bug in qemu:
"'libvirt-4-format' is not in this backing file chain"
Additionally one weird thing happens with block-stream (blockpull). If I
pass the layer below the copy-on-read as 'device', everything works.
This is kind of weird as the documentation for that is the same. If I
pass the nodename of copy-on-read.
Max, Kevin, could you please comment on the block-stream part and
possibly also on the plans to fix the issue with block-commit?
Cc: Max Reitz <mreitz(a)redhat.com>
CC: Kevin Wolf <kwolf(a)redhat.com>
https://bugzilla.redhat.com/show_bug.cgi?id=1792195
Peter Krempa (4):
qemu: blockcopy: Actually unplug unused images when mirror job fails
to start
qemu: domain: Extract code to determine topmost nodename to
qemuDomainDiskGetTopNodename
qemu: Fix value of 'device' argument for blockdev-mirror
qemu: Fix value of 'device' argument for block-commit
src/qemu/qemu_domain.c | 38 ++++++++++++++++++++++++++------------
src/qemu/qemu_domain.h | 4 ++++
src/qemu/qemu_driver.c | 6 +++---
src/qemu/qemu_migration.c | 2 +-
4 files changed, 34 insertions(+), 16 deletions(-)
--
2.24.1