query-named-block-nodes should not return information that is related
to the attached BlockBackend rather than the node itself, so throttling
information needs to be removed from it.
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
Reviewed-by: NMax Reitz <mreitz@redhat.com>

Since virtio-blk implements request merging itself these days, the only
remaining users are test cases for the function. That doesn't make the
function exactly useful any more.
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
Reviewed-by: NMax Reitz <mreitz@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>

Running an iotests-based Python test directly might appear to work,
but may fail in subtle ways and is insecure:

- It creates files with predictable file names in a world-writable
  location (/var/tmp).

- Tests expect the environment to be set up by check. E.g. 041 and 055
  may take the wrong code paths if QEMU_DEFAULT_MACHINE is not
  set. This can lead to false negatives.

Instead fail hard and tell the user we want to be run via "check".

The actual environment expected by the tests is currently only defined
by the implementation of "check". We use two of the environment
variables set by "check" as indication of whether we're being run via
"check". Anyone writing their own test runner (replacing "check") will
need to replicate the full environment (in a broader sense, not just
environment variables) provided by "check" anyway, including setting
the two environment variables we check. Whereas a regular developer
just trying to invoke the tests usually won't have both of these
defined in their environment so we can catch their mistake and give
out useful advice.
Signed-off-by: NSascha Silbe <silbe@linux.vnet.ibm.com>
Reviewed-by: NBo Tu <tubo@linux.vnet.ibm.com>
Message-id: 1461094442-16014-1-git-send-email-silbe@linux.vnet.ibm.com
Signed-off-by: NMax Reitz <mreitz@redhat.com>

This adds support for testing the LUKS driver with the block
I/O test framework.

   cd tests/qemu-io-tests
   ./check -luks

A handful of test cases are modified to work with luks

 - 004 - whitelist luks format
 - 012 - use TEST_IMG_FILE instead of TEST_IMG for file ops
 - 048 - use TEST_IMG_FILE instead of TEST_IMG for file ops.
         don't assume extended image contents is all zeros,
         explicitly initialize with zeros
         Make file size smaller to avoid having to decrypt
         1 GB of data.
 - 052 - don't assume initial image contents is all zeros,
         explicitly initialize with zeros
 - 100 - don't assume initial image contents is all zeros,
         explicitly initialize with zeros

With this patch applied, the results are as follows:

  Passed: 001 002 003 004 005 008 009 010 011 012 021 032 043
          047 048 049 052 087 100 134 143
  Failed: 033 120 140 145
 Skipped: 007 013 014 015 017 018 019 020 022 023 024 025 026
          027 028 029 030 031 034 035 036 037 038 039 040 041
          042 043 044 045 046 047 049 050 051 053 054 055 056
          057 058 059 060 061 062 063 064 065 066 067 068 069
          070 071 072 073 074 075 076 077 078 079 080 081 082
          083 084 085 086 087 088 089 090 091 092 093 094 095
          096 097 098 099 101 102 103 104 105 107 108 109 110
          111 112 113 114 115 116 117 118 119 121 122 123 124
          128 129 130 131 132 133 134 135 136 137 138 139 141
          142 144 146 148 150 152

The reasons for the failed tests are:

 - 033 - needs adapting to use image opts syntax with blkdebug
         and test image in order to correctly set align property
 - 120 - needs adapting to use correct -drive syntax for luks
 - 140 - needs adapting to use correct -drive syntax for luks
 - 145 - needs adapting to use correct -drive syntax for luks

The vast majority of skipped tests are exercising code that is
qcow2 specific, though a couple could probably be usefully
enabled for luks too.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>
Message-id: 1462896689-18450-4-git-send-email-berrange@redhat.com
Signed-off-by: NMax Reitz <mreitz@redhat.com>

The LUKS block driver tests will require the ability to specify
encryption secrets with block devices. This requires using the
--object argument to qemu-img/qemu-io to create a 'secret'
object.

When the IMGKEYSECRET env variable is set, it provides the
password to be associated with a secret called 'keysec0'

The _qemu_img_wrapper function isn't modified as that needs
to cope with differing syntax for subcommands, so can't be
made to use the image opts syntax unconditionally.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>
Message-id: 1462896689-18450-3-git-send-email-berrange@redhat.com
Signed-off-by: NMax Reitz <mreitz@redhat.com>

Currently all block tests use the traditional syntax for images
just specifying a filename. To support the LUKS driver without
resorting to JSON, the tests need to be able to use the new
--image-opts argument to qemu-img and qemu-io.

This introduces a new env variable IMGOPTSSYNTAX. If this is
set to 'true', then qemu-img/qemu-io should use --image-opts.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>
Message-id: 1462896689-18450-2-git-send-email-berrange@redhat.com
Signed-off-by: NMax Reitz <mreitz@redhat.com>

There's no reason to require the user to specify a flag just so
they can pass in unaligned numbers.  Keep 'read -p' and 'write -p'
as no-ops so that I don't have to hunt down and update all users
of qemu-io, but otherwise make their behavior default as 'read' and
'write'.  Also fix 'write -z', 'readv', 'writev', 'writev',
'aio_read', 'aio_write', and 'aio_write -z'.  For now, 'read -b',
'write -b', and 'write -c' still require alignment (and 'multiwrite',
but that's slated to die soon).

qemu-iotest 23 is updated to match, as the only test that was
previously explicitly expecting an error on an unaligned request.
Signed-off-by: NEric Blake <eblake@redhat.com>
Message-id: 1462677405-4752-5-git-send-email-eblake@redhat.com
Reviewed-by: NMax Reitz <mreitz@redhat.com>
Signed-off-by: NMax Reitz <mreitz@redhat.com>

It should redirect stdout to /dev/null first,
then redirect stderr to whatever stdout currently points at.
Signed-off-by: NWei Jiangang <weijg.fnst@cn.fujitsu.com>
Message-id: 1461665601-14908-1-git-send-email-weijg.fnst@cn.fujitsu.com
Reviewed-by: NEric Blake <eblake@redhat.com>
Signed-off-by: NMax Reitz <mreitz@redhat.com>

Vmdk images have metadata to indicate the vmware virtual
hardware version image was created/tested to run with.
Allow users to specify that version via new 'hwversion'
option.

[ kwolf: Adjust qemu-iotests common.filter ]
Signed-off-by: NJanne Karhunen <Janne.Karhunen@gmail.com>
Reviewed-by: NFam Zheng <famz@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

This is the regression test for the virtual size mismatch issue between
target and source images.

[ kwolf: Added test_unaligned_with_update ]
Signed-off-by: NFam Zheng <famz@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
Reviewed-by: NMax Reitz <mreitz@redhat.com>
Reviewed-by: NJeff Cody <jcody@redhat.com>

This retrieves the virtual size of the image out of qemu-img info.
Signed-off-by: NFam Zheng <famz@redhat.com>
Reviewed-by: NMax Reitz <mreitz@redhat.com>
Reviewed-by: NJeff Cody <jcody@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

The last sub-chunk is rounded up to the copy granularity in the target
image, resulting in a larger size than the source.

Add a function to clip the copied sectors to the end.

This undoes the "wrong" changes to tests/qemu-iotests/109.out in
e5b43573. The remaining two offset changes are okay.

[ kwolf: Use DIV_ROUND_UP to calculate nb_chunks now ]
Reported-by: NKevin Wolf <kwolf@redhat.com>
Signed-off-by: NFam Zheng <famz@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
Reviewed-by: NMax Reitz <mreitz@redhat.com>
Reviewed-by: NJeff Cody <jcody@redhat.com>

Block nodes are now assigned names automatically, therefore the test
case is fragile in using fixed indices in result. Introduce a method in
iotests.py and do the matching more sensibly.
Signed-off-by: NFam Zheng <famz@redhat.com>
Message-id: 1460518995-1338-1-git-send-email-famz@redhat.com
Signed-off-by: NMax Reitz <mreitz@redhat.com>

Do not place the valgrind log file at a predictable path in a
world-writable location. Use the common scratch directory (${TEST_DIR})
instead.
Signed-off-by: NSascha Silbe <silbe@linux.vnet.ibm.com>
Reviewed-by: NBo Tu <tubo@linux.vnet.ibm.com>
Message-id: 1460472980-26319-5-git-send-email-silbe@linux.vnet.ibm.com
Reviewed-by: NMax Reitz <mreitz@redhat.com>
Signed-off-by: NMax Reitz <mreitz@redhat.com>

The previous commit removed the last usage of ${tmp} inside the tests
themselves; the only remaining users are sourced by check. So we can now
drop this variable from the tests.
Signed-off-by: NSascha Silbe <silbe@linux.vnet.ibm.com>
Reviewed-by: NBo Tu <tubo@linux.vnet.ibm.com>
Message-id: 1460472980-26319-4-git-send-email-silbe@linux.vnet.ibm.com
Reviewed-by: NMax Reitz <mreitz@redhat.com>
Signed-off-by: NMax Reitz <mreitz@redhat.com>

_do() was never used and possibly creates temporary files at
predictable, world-writable locations. Get rid of it.
Signed-off-by: NSascha Silbe <silbe@linux.vnet.ibm.com>
Reviewed-by: NBo Tu <tubo@linux.vnet.ibm.com>
Message-id: 1460472980-26319-3-git-send-email-silbe@linux.vnet.ibm.com
Reviewed-by: NMax Reitz <mreitz@redhat.com>
Signed-off-by: NMax Reitz <mreitz@redhat.com>

_within_tolerance() isn't used anymore and possibly creates temporary
files at predictable, world-writable locations. Get rid of it.

If it's needed again in the future it can be revived easily and fixed up
to use TEST_DIR and / or safely created temporary files.
Signed-off-by: NSascha Silbe <silbe@linux.vnet.ibm.com>
Reviewed-by: NBo Tu <tubo@linux.vnet.ibm.com>
Message-id: 1460472980-26319-2-git-send-email-silbe@linux.vnet.ibm.com
Reviewed-by: NMax Reitz <mreitz@redhat.com>
Signed-off-by: NMax Reitz <mreitz@redhat.com>

Commit 57d6a428 broke blk_aio_write_zeroes() because in some write
functions in the call path don't have an explicit length argument but
reuse qiov->size instead. Which is great, except that write_zeroes
doesn't have a qiov, which this commit interprets as 0 bytes.
Consequently, blk_aio_write_zeroes() didn't effectively do anything.

This patch introduces an explicit acb->bytes in BlkAioEmAIOCB and uses
that instead of acb->rwco.size.

The synchronous version of the function is okay because it does pass a
qiov (with the right size and a NULL pointer as its base).
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
Reviewed-by: NMax Reitz <mreitz@redhat.com>

The __all__ list contained a typo for as long as the iotests module
existed. That typo prevented "from iotests import *" (which is the
only case where iotests.__all__ is used at all) from ever working.

The names used by iotests are highly prone to name collisions, so
importing them all unconditionally is a bad idea anyway. Since __all__
is not adding any value, let's just get rid of it.

Fixes: f345cfd0 ("qemu-iotests: add iotests Python module")
Signed-off-by: NSascha Silbe <silbe@linux.vnet.ibm.com>
Reviewed-by: NBo Tu <tubo@linux.vnet.ibm.com>
Message-id: 1459848109-29756-8-git-send-email-silbe@linux.vnet.ibm.com
Reviewed-by: NMax Reitz <mreitz@redhat.com>
Signed-off-by: NMax Reitz <mreitz@redhat.com>

None of the other test cases explicitly enable KVM and there's no
obvious reason for 068 to require it. Drop this so all test cases can be
executed in environments where KVM is not available (e.g. because the
user doesn't have sufficient permissions to access /dev/kvm).
Signed-off-by: NSascha Silbe <silbe@linux.vnet.ibm.com>
Reviewed-by: NBo Tu <tubo@linux.vnet.ibm.com>
Message-id: 1459848109-29756-6-git-send-email-silbe@linux.vnet.ibm.com
Signed-off-by: NMax Reitz <mreitz@redhat.com>

qemu-iotests test case 148 already had some code for skipping the test
if quorum support is missing, but it didn't work in all
cases. TestQuorumEvents.setUp() gets run before the actual test class
(which contains the skipping code) and tries to start qemu with a drive
using the quorum driver. For some reason this works fine when using
qcow2, but fails for raw.

As the entire test case requires quorum, just check for availability
before even starting the test suite. Introduce a verify_quorum()
function in iotests.py for this purpose so future test cases can make
use of it.
Signed-off-by: NSascha Silbe <silbe@linux.vnet.ibm.com>
Reviewed-by: NBo Tu <tubo@linux.vnet.ibm.com>
Message-id: 1459848109-29756-5-git-send-email-silbe@linux.vnet.ibm.com
Reviewed-by: NMax Reitz <mreitz@redhat.com>
Signed-off-by: NMax Reitz <mreitz@redhat.com>

On error, VM.launch() cleaned up the monitor unix socket, but left the
qtest unix socket behind. This caused the remaining sub-tests to fail
with EADDRINUSE:

+======================================================================
+ERROR: testQuorum (__main__.TestFifoQuorumEvents)
+----------------------------------------------------------------------
+Traceback (most recent call last):
+  File "148", line 63, in setUp
+    self.vm.launch()
+  File "/home6/silbe/qemu/tests/qemu-iotests/iotests.py", line 247, in launch
+    self._qmp.accept()
+  File "/home6/silbe/qemu/tests/qemu-iotests/../../scripts/qmp/qmp.py", line 141, in accept
+    return self.__negotiate_capabilities()
+  File "/home6/silbe/qemu/tests/qemu-iotests/../../scripts/qmp/qmp.py", line 57, in __negotiate_capabilities
+    raise QMPConnectError
+QMPConnectError
+
+======================================================================
+ERROR: testQuorum (__main__.TestQuorumEvents)
+----------------------------------------------------------------------
+Traceback (most recent call last):
+  File "148", line 63, in setUp
+    self.vm.launch()
+  File "/home6/silbe/qemu/tests/qemu-iotests/iotests.py", line 244, in launch
+    self._qtest = qtest.QEMUQtestProtocol(self._qtest_path, server=True)
+  File "/home6/silbe/qemu/tests/qemu-iotests/../../scripts/qtest.py", line 33, in __init__
+    self._sock.bind(self._address)
+  File "/usr/lib64/python2.7/socket.py", line 224, in meth
+    return getattr(self._sock,name)(*args)
+error: [Errno 98] Address already in use

Fix this by cleaning up both the monitor socket and the qtest socket iff
they exist.
Signed-off-by: NSascha Silbe <silbe@linux.vnet.ibm.com>
Reviewed-by: NBo Tu <tubo@linux.vnet.ibm.com>
Message-id: 1459848109-29756-4-git-send-email-silbe@linux.vnet.ibm.com
Reviewed-by: NMax Reitz <mreitz@redhat.com>
Signed-off-by: NMax Reitz <mreitz@redhat.com>

Commit 61de4c68 [block: Remove BDRV_O_CACHE_WB] updated the reference
output for PCs, but neglected to do the same for the generic reference
output file. Fix 051 on all non-PC architectures by applying the same
change to the generic output file.

Fixes: 61de4c68 ("block: Remove BDRV_O_CACHE_WB")
Signed-off-by: NSascha Silbe <silbe@linux.vnet.ibm.com>
Reviewed-by: NBo Tu <tubo@linux.vnet.ibm.com>
Message-id: 1459848109-29756-3-git-send-email-silbe@linux.vnet.ibm.com
Reviewed-by: NMax Reitz <mreitz@redhat.com>
Signed-off-by: NMax Reitz <mreitz@redhat.com>

Placing files with predictable or even hard-coded names in /tmp is a
security risk and can prevent or disturb operation on a multi-user
machine. Place them inside the "scratch" directory instead, as we
already do for most other test-related files.
Signed-off-by: NSascha Silbe <silbe@linux.vnet.ibm.com>
Reviewed-by: NBo Tu <tubo@linux.vnet.ibm.com>
Message-id: 1459848109-29756-2-git-send-email-silbe@linux.vnet.ibm.com
Reviewed-by: NMax Reitz <mreitz@redhat.com>
Signed-off-by: NMax Reitz <mreitz@redhat.com>

The actual on-disk size of a file does not only depend on factors qemu
can control. Thus, we should not depend on this to determine whether a
file has indeed been fully allocated. Instead, use qemu-img map and hope
that if an area is referenced, it is indeed allocated, too.

Also, limit the supported image formats to raw and qcow2 because the
actual qemu-img map output may depend on the image format.
Signed-off-by: NMax Reitz <mreitz@redhat.com>
Tested-by: NPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

This patch fixes longstanding issue with 026 iotest. Unfortunately,
this test contains 2 versions of the correct output, one for cached
writes and one for non-cached ones. People tends to fix only one
version of output of the test and thus noncached version becomes
broken. Unfortunately, it is default in tests/check-block.sh

The following problematic commits were made:
    commit 3b5e14c7
    Author: Max Reitz <mreitz@redhat.com>
    Date:   Tue Dec 2 18:32:51 2014 +0100
    qcow2: Flushing the caches in qcow2_close may fail

    commit a069e2f1
    Author: John Snow <jsnow@redhat.com>
    Date:   Fri Feb 6 16:26:17 2015 -0500
    blkdebug: fix "once" rule

    commit b106ad91
    Author: Kevin Wolf <kwolf@redhat.com>
    Date:   Fri Mar 28 18:06:31 2014 +0100
    qcow2: Don't rely on free_cluster_index in alloc_refcount_block()
Signed-off-by: NPavel Butsykin <pbutsykin@virtuozzo.com>
Signed-off-by: NDenis V. Lunev <den@openvz.org>
CC: Max Reitz <mreitz@redhat.com>
CC: John Snow <jsnow@redhat.com>
CC: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

Do the same as other scripts, to pick the correct interpreter between
python2 and python3 from the environment.
Signed-off-by: NFam Zheng <famz@redhat.com>
Message-id: 1459504593-2692-1-git-send-email-famz@redhat.com
Signed-off-by: NMax Reitz <mreitz@redhat.com>

Passing -S 0 to qemu-img convert should result in all source data being
copied to the output, even if that source data is known to be 0. The
output image should therefore have exactly the same size on disk as an
image which we explicitly filled with data.
Signed-off-by: NMax Reitz <mreitz@redhat.com>
Reviewed-by: NFam Zheng <famz@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

When passing -S 0 to qemu-img convert, the target image is supposed to
be fully allocated. Right now, this is not the case if the source image
contains areas which bdrv_get_block_status() reports as being zero.

This patch changes a zeroed area's status from BLK_ZERO to BLK_DATA
before invoking convert_write() if -S 0 has been specified. In addition,
the check whether convert_read() actually needs to do anything
(basically only if the current area is a BLK_DATA area) is pulled out of
that function to the caller.

If -S 0 has been specified, zeroed areas need to be written as data to
the output, thus they then have to be accounted when calculating the
progress made.

This patch changes the reference output for iotest 122; contrary to what
it assumed, -S 0 really should allocate everything in the output, not
just areas that are filled with zeros (as opposed to being zeroed).
Signed-off-by: NMax Reitz <mreitz@redhat.com>
Reviewed-by: NFam Zheng <famz@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

The previous patches have successively made blk->enable_write_cache the
true source for the information whether a writethrough mode must be
implemented. The corresponding BDRV_O_CACHE_WB is only useless baggage
we're carrying around, so now's the time to remove it.

At the same time, we remove the 'cache.writeback' option parsing on the
BDS level as the only effect was setting the BDRV_O_CACHE_WB flag.

This change requires test cases that explicitly enabled the option to
drop it. Other than that and the change of the error message when
writethrough is enabled on the BDS level (from "Can't set writethrough
mode" to "doesn't support the option"), there should be no change in
behaviour.
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
Reviewed-by: NMax Reitz <mreitz@redhat.com>

We must forbid changing the WCE flag in bdrv_reopen() in the same patch,
as otherwise the behaviour would change so that the flag takes
precedence over the explicitly specified option.

The correct value of the WCE flag depends on the BlockBackend user (e.g.
guest device) and isn't a decision that the QMP client makes, so this
change is what we want.
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
Reviewed-by: NMax Reitz <mreitz@redhat.com>

Now that WCE is handled on the BlockBackend level, the flag is
meaningless for BDSes. As the schema requires us to fill the field,
we return an enabled write cache for them.

Note that this means that querying the BlockBackend name may return
writethrough as the cache information, whereas querying the node-name of
the root of that same BlockBackend will return writeback.

This may appear odd at first, but it actually makes sense because it
correctly repesents the layer that implements the WCE handling. This
becomes more apparent when you consider nodes that are the root node of
multiple BlockBackends, where each BB can have its own WCE setting.
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
Reviewed-by: NMax Reitz <mreitz@redhat.com>

Whether a write cache is used or not is a decision that concerns the
user (e.g. the guest device) rather than the backend. It was already
logically part of the BB level as bdrv_move_feature_fields() always kept
it on top of the BDS tree; with this patch, the core of it (the actual
flag and the additional flushes) is also implemented there.

Direct callers of bdrv_open() must pass BDRV_O_CACHE_WB now if bs
doesn't have a BlockBackend attached.
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
Reviewed-by: NMax Reitz <mreitz@redhat.com>

It is important that the QEMU luks implementation retains 100%
compatibility with the reference implementation provided by
the combination of the linux kernel dm-crypt module and cryptsetup
userspace tools.

There is a matrix of tests to be performed with different sets
of encryption settings. For each matrix entry, two tests will
be performed. One will create a LUKS image with the cryptsetup
tool and then do I/O with both cryptsetup & qemu-io. The other
will create the image with qemu-img and then again do I/O with
both cryptsetup and qemu-io.

The new I/O test 149 performs interoperability testing between
QEMU and the reference implementation. Such testing inherantly
requires elevated privileges, so to this this the user must have
configured passwordless sudo access. The test will automatically
skip if sudo is not available.

The test has to be run explicitly thus:

    cd tests/qemu-iotests
    ./check -luks 149
Reviewed-by: NEric Blake <eblake@redhat.com>
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

For a couple of releases we have been warning

  Encrypted images are deprecated
  Support for them will be removed in a future release.
  You can use 'qemu-img convert' to convert your image to an unencrypted one.

This warning was issued by system emulators, qemu-img, qemu-nbd
and qemu-io. Such a broad warning was issued because the original
intention was to rip out all the code for dealing with encryption
inside the QEMU block layer APIs.

The new block encryption framework used for the LUKS driver does
not rely on the unloved block layer API for encryption keys,
instead using the QOM 'secret' object type. It is thus no longer
appropriate to warn about encryption unconditionally.

When the qcow/qcow2 drivers are converted to use the new encryption
framework too, it will be practical to keep AES-CBC support present
for use in qemu-img, qemu-io & qemu-nbd to allow for interoperability
with older QEMU versions and liberation of data from existing encrypted
qcow2 files.

This change moves the warning out of the generic block code and
into the qcow/qcow2 drivers. Further, the warning is set to only
appear when running the system emulators, since qemu-img, qemu-io,
qemu-nbd are expected to support qcow2 encryption long term now that
the maint burden has been eliminated.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

Add a 'log' method to iotests.py which prints messages to
stdout, with optional filtering of data. Port over some
standard filters already present in the shell common.filter
code to be usable in python too.
Reviewed-by: NEric Blake <eblake@redhat.com>
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

The iotests.py helper provides a main() method for running
tests via the python unit test framework. Not all tests
will want to use this, so refactor it to split the testing
of compatible formats and platforms into separate helper
methods
Reviewed-by: NEric Blake <eblake@redhat.com>
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

The python I/O tests helper for running qemu-img/qemu-io
setup stdout to be captured to a pipe, but left stderr
untouched. As a result, if something failed in qemu-img/
qemu-io, data written to stderr would get output directly
and not line up with data on the test stdout due to
buffering.  If we explicitly redirect stderr to the same
pipe as stdout, things are much clearer when they go
wrong.
Reviewed-by: NEric Blake <eblake@redhat.com>
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

Writethrough mode is going to become a BlockBackend feature rather than
a BDS one, so forbid it in places where we won't be able to support it
when the code finally matches the envisioned design.

We only allowed setting the cache mode of non-root nodes after the 2.5
release, so we're still free to make this change.

The target of block jobs is now always opened in a writeback mode
because it doesn't have a BlockBackend attached. This makes more sense
anyway because block jobs know when to flush. If the graph is modified
on job completion, the original cache mode moves to the new root, so
for the guest device writethough always stays enabled if it was
configured this way.
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>

First of all, we're generally not writing to backing files, but when we
do, it's in the context of block jobs which know very well when to flush
the image.
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>