1084159b31
Modern way is using blockdev-add + blockdev-backup, which provides a lot more control on how target is opened. As example of drive-backup problems consider the following: User of drive-backup expects that target will be opened in the same cache and aio mode as source. Corresponding logic is in drive_backup_prepare(), where we take bs->open_flags of source. It works rather bad if source was added by blockdev-add. Assume source is qcow2 image. On blockdev-add we should specify aio and cache options for file child of qcow2 node. What happens next: drive_backup_prepare() looks at bs->open_flags of qcow2 source node. But there no BDRV_O_NOCAHE neither BDRV_O_NATIVE_AIO: BDRV_O_NOCAHE is places in bs->file->bs->open_flags, and BDRV_O_NATIVE_AIO is nowhere, as file-posix parse options and simply set s->use_linux_aio. The documentation is updated in a minimal way, so that drive-backup is noted only as a deprecated command, and blockdev-backup used in most of places. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> |
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spin | ||
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amd-memory-encryption.txt | ||
block-replication.txt | ||
bypass-iommu.txt | ||
can.txt | ||
ccid.txt | ||
COLO-FT.txt | ||
colo-proxy.txt | ||
conf.py | ||
confidential-guest-support.txt | ||
defs.rst.inc | ||
hyperv.txt | ||
igd-assign.txt | ||
image-fuzzer.txt | ||
index.rst | ||
memory-hotplug.txt | ||
meson.build | ||
multi-thread-compression.txt | ||
multiseat.txt | ||
nvdimm.txt | ||
papr-pef.txt | ||
pci_expander_bridge.txt | ||
pcie_pci_bridge.txt | ||
pcie.txt | ||
pvrdma.txt | ||
qcow2-cache.txt | ||
qdev-device-use.txt | ||
qemu_logo.pdf | ||
qemu-option-trace.rst.inc | ||
qemupciserial.inf | ||
rdma.txt | ||
replay.txt | ||
spice-port-fqdn.txt | ||
throttle.txt | ||
u2f.txt | ||
virtio-balloon-stats.txt | ||
xbzrle.txt | ||
xen-save-devices-state.txt |