Commit Graph

3 Commits

Author SHA1 Message Date
Eric Blake 4096974e18 qcow2: fix image corruption on commit with persistent bitmap
If an image contains persistent bitmaps, we cannot use the
fast path of bdrv_make_empty() to clear the image during
qemu-img commit, because that will lose the clusters related
to the bitmaps.

Also leave a comment in qcow2_read_extensions to remind future
feature additions to think about fast-path removal, since we
just barely fixed the same bug for LUKS encryption.

It's a pain that qemu-img has not yet been taught to manipulate,
or even at a very minimum display, information about persistent
bitmaps; instead, we have to use QMP commands.  It's also a
pain that only qeury-block and x-debug-block-dirty-bitmap-sha256
will allow bitmap introspection; but the former requires the
node to be hooked to a block device, and the latter is experimental.

Signed-off-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2017-11-17 18:21:01 +01:00
Eric Blake f82c5b17ea iotests: Improve image-clear tests on non-aligned image
Tweak 097 and 176 to operate on an image that is not cluster-aligned,
to give further coverage of clearing out an entire image, including
the recent fix to eliminate the difference between fast path (97) and
slow (176) for qcow2.  Also tested on qcow (97 only, since qcow lacks
snapshots).

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-id: 20170331185356.2479-4-eblake@redhat.com
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2017-04-03 17:11:40 +02:00
Daniel P. Berrange 07ff948bd1 iotests: fix 097 when run with qcow
The previous commit:

  commit a3e1505dae
  Author: Eric Blake <eblake@redhat.com>
  Date:   Mon Dec 5 09:49:34 2016 -0600

    qcow2: Don't strand clusters near 2G intervals during commit

extended the 097 test case so that it did two passes, once
with an internal snapshot, once without.

qcow (v1) does not support internal snapshots, so this change
broke test 097 when run against qcow.

This splits 097 in two, creating a new 176 that tests the
internal snapshot codepath, effectively putting 097 back
to its content before the above commit.

Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <20170221115512.21918-8-berrange@redhat.com>
[eblake: test collisions: s/173/176/g]
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-id: 20170331185356.2479-2-eblake@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
2017-04-03 17:11:40 +02:00