The point of 'qemu-img convert --bitmaps' is to be a convenience for
actions that are already possible through a string of smaller
'qemu-img bitmap' sub-commands. One situation not accounted for
already is that if a source image contains an inconsistent bitmap (for
example, because a qemu process died abruptly before flushing bitmap
state), the user MUST delete those inconsistent bitmaps before
anything else useful can be done with the image.
We don't want to delete inconsistent bitmaps by default: although a
corrupt bitmap is only a loss of optimization rather than a corruption
of user-visible data, it is still nice to require the user to opt in
to the fact that they are aware of the loss of the bitmap. Still,
requiring the user to check 'qemu-img info' to see whether bitmaps are
consistent, then use 'qemu-img bitmap --remove' to remove offenders,
all before using 'qemu-img convert', is a lot more work than just
adding a knob 'qemu-img convert --bitmaps --skip-broken-bitmaps' which
opts in to skipping the broken bitmaps.
After testing the new option, also demonstrate the way to manually fix
things (either deleting bad bitmaps, or re-creating them as empty) so
that it is possible to convert without the option.
Fixes: https://bugzilla.redhat.com/show_bug.cgi?id=1946084
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <20210709153951.2801666-4-eblake@redhat.com>
[eblake: warning message tweak, test enhancements]
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
=== This is the QEMU I/O test suite ===
* Intro
This package contains a simple test suite for the I/O layer of qemu.
It does not require a guest, but only the qemu, qemu-img and qemu-io
binaries. This does limit it to exercise the low-level I/O path only
but no actual block drivers like ide, scsi or virtio.
* Usage
Just run ./check to run all tests for the raw image format, or ./check
-qcow2 to test the qcow2 image format. The output of ./check -h explains
additional options to test further image formats or I/O methods.
* Feedback and patches
Please send improvements to the test suite, general feedback or just
reports of failing tests cases to qemu-devel@nongnu.org with a CC:
to qemu-block@nongnu.org.