Commit Graph

721 Commits

Author SHA1 Message Date
Kevin Wolf
0a4279d97c block/qapi: Move 'aio' option to file driver
The option whether or not to use a native AIO interface really isn't a
generic option for all drivers, but only applies to the native file
protocols. This patch moves the option in blockdev-add to the
appropriate places (raw-posix and raw-win32).

We still have to keep the flag BDRV_O_NATIVE_AIO for compatibility
because so far the AIO option was usually specified on the wrong layer
(the top-level format driver, which didn't even look at it) and then
inherited by the protocol driver (where it was actually used). We can't
forbid this use except in new interfaces.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
2016-09-29 14:13:39 +02:00
Kevin Wolf
0ffcdd9c06 block: Drop aio/cache consistency check from qmp_blockdev_add()
The TODO comment has been addressed a while ago and this is now checked
in raw-posix, so we don't have to special case this in blockdev-add any
more.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
2016-09-29 14:13:38 +02:00
Kevin Wolf
9ec8873e68 block: Remove BB interface from blockdev-add/del
With this patch, blockdev-add always works on a node level, i.e. it
creates a BDS, but no BB. Consequently, x-blockdev-del doesn't need the
'device' option any more, but 'node-name' becomes mandatory.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2016-09-23 13:45:36 +02:00
Kevin Wolf
7864588150 qemu-iotests/141: Avoid blockdev-add with id
We want to remove the 'id' option for blockdev-add. This removes one
user of the option and makes it use only node names.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2016-09-23 13:45:36 +02:00
Kevin Wolf
e467da7b92 block: Avoid printing NULL string in error messages
Even for nodes that have a BlockBackend attached, bdrv_get_parent_name()
can return NULL if the BB is anonymous (e.g. it belongs to a block job
or a device that was created with a drive=<node-name> option).

Remove the information from the error message. The user probably knows
already why the node is still in use.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2016-09-23 13:45:36 +02:00
Kevin Wolf
62acae8a9d qemu-iotests/139: Avoid blockdev-add with id
We want to remove the 'id' option for blockdev-add. This removes one
user of the option and makes it use only node names.

Some test cases that used to work with an unattached BlockBackend are
removed, either because they don't make sense with an attached device or
because the equivalent test case with an attached device already exists.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2016-09-23 13:45:36 +02:00
Kevin Wolf
eed875838e qemu-iotests/124: Avoid blockdev-add with id
We want to remove the 'id' option for blockdev-add. This removes one
user of the option and makes it use only node names.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2016-09-23 13:45:36 +02:00
Kevin Wolf
e4fd2e9dfc qemu-iotests/118: Avoid blockdev-add with id
We want to remove the 'id' option for blockdev-add. This removes one
user of the option and makes it use only node names.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2016-09-23 13:45:36 +02:00
Kevin Wolf
1f4c4d7361 qemu-iotests/117: Avoid blockdev-add with id
We want to remove the 'id' option for blockdev-add. This removes one
user of the option and makes it use only node names.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2016-09-23 13:45:36 +02:00
Kevin Wolf
5feb08ed8f qemu-iotests/087: Avoid blockdev-add with id
We want to remove the 'id' option for blockdev-add. This removes one
user of the option and makes it use only node names.

The test cases that test conflicts between the 'id' option to
blockdev-add and existing block devices or the 'node-name' of the same
command can be removed because it won't be possible to specify this at
the end of the series.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2016-09-23 13:45:36 +02:00
Kevin Wolf
26d5fa10ff qemu-iotests/081: Avoid blockdev-add with id
We want to remove the 'id' option for blockdev-add. This removes one
user of the option and makes it use only node names.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2016-09-23 13:45:36 +02:00
Kevin Wolf
ffec99f722 qemu-iotests/071: Avoid blockdev-add with id
We want to remove the 'id' option for blockdev-add. This removes one
user of the option and makes it use only node names.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2016-09-23 13:45:36 +02:00
Kevin Wolf
522ce4ecd4 qemu-iotests/067: Avoid blockdev-add with id
We want to remove the 'id' option for blockdev-add. This removes one
user of the option and makes it use only node names.

In order to keep the test meaningful, some instances of query-block that
want to check whether the node still exists and would now turn up empty
must be converted to query-named-block-nodes (which also return the
protocol level node, but that shouldn't hurt).

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2016-09-23 13:45:36 +02:00
Kevin Wolf
476fb028bf qemu-iotests/041: Avoid blockdev-add with id
We want to remove the 'id' option for blockdev-add. This removes one
user of the option and makes it use only node names.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2016-09-23 13:45:36 +02:00
Kevin Wolf
486b88bdc8 qemu-iotests/118: Test media change with qdev name
We just added the option to use qdev device names in all device related
block QMP commands. This patch converts some of the test cases in 118 to
use qdev device names instead of BlockBackend names to cover the new
way. It converts cases for each of the media change commands, but only
for CD-ROM and not everywhere, so that the old way is still tested, too.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2016-09-23 13:45:35 +02:00
Daniel P. Berrange
bb9f8dd0e1 qcow2: fix encryption during cow of sectors
Broken in previous commit:

  commit aaa4d20b49
  Author: Kevin Wolf <kwolf@redhat.com>
  Date:   Wed Jun 1 15:21:05 2016 +0200

      qcow2: Make copy_sectors() byte based

The copy_sectors() code was originally using the 'sector'
parameter for encryption, which was passed in by the caller
from the QCowL2Meta.offset field (aka the guest logical
offset).

After the change, the code is using 'cluster_offset' which
was passed in from QCow2L2Meta.alloc_offset field (aka the
host physical offset).

This would cause the data to be encrypted using an incorrect
initialization vector which will in turn cause later reads
to return garbage.

Although current qcow2 built-in encryption is blocked from
usage in the emulator, one could still hit this if writing
to the file via qemu-{img,io,nbd} commands.

Cc: qemu-stable@nongnu.org
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-09-23 13:36:09 +02:00
Vladimir Sementsov-Ogievskiy
819cec0114 iotest 055: refactor and speed up
Source disk is created and filled with test data before each test case.
Instead initialize it once for the whole unit.

Test disk filling patterns are merged into one pattern.

Also TestSetSpeed used different image_len for source and target (by
mistake) - this is automatically fixed here.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-id: 1470748523-13856-1-git-send-email-vsementsov@virtuozzo.com
Reviewed-by: Pavel Butsykin <pbutsykin@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2016-09-20 22:12:57 +02:00
Reda Sallahi
f7c1553388 qemu-img: add skip option to dd
This adds the skip option which allows qemu-img dd to skip a number of blocks
before copying the input.

A test case was added to test the skip option.

Signed-off-by: Reda Sallahi <fullmanet@gmail.com>
Message-id: 20160810141609.32727-1-fullmanet@gmail.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
2016-09-20 22:10:57 +02:00
Reda Sallahi
86ce1f6e2b qemu-img: add the 'dd' subcommand
This patch adds a basic dd subcommand analogous to dd(1) to qemu-img.

For the start, this implements the bs, if, of and count options and requires
both if and of to be specified (no stdin/stdout if not specified) and doesn't
support tty, pipes, etc.

The image format must be specified with -O for the output if the raw format
is not the intended one.

Two tests are added to test qemu-img dd.

Signed-off-by: Reda Sallahi <fullmanet@gmail.com>
Message-id: 20160810024312.14544-1-fullmanet@gmail.com
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
[mreitz: Moved test 158 to 170]
Signed-off-by: Max Reitz <mreitz@redhat.com>
2016-09-20 22:10:57 +02:00
Kevin Wolf
c0088d79a7 qemu-iotests: Log QMP traffic in debug mode
Python tests are already annoying enough to debug. With QMP traffic
available it's a little bit easier at least.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2016-09-05 19:06:48 +02:00
Pavel Butsykin
00198ecc77 qemu-iotests: add vmdk for test backup compression in 055
The vmdk format has support for compression, it would be fine to add it for
the test backup compression

Signed-off-by: Pavel Butsykin <pbutsykin@virtuozzo.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Denis V. Lunev <den@openvz.org>
CC: Jeff Cody <jcody@redhat.com>
CC: Markus Armbruster <armbru@redhat.com>
CC: Eric Blake <eblake@redhat.com>
CC: John Snow <jsnow@redhat.com>
CC: Stefan Hajnoczi <stefanha@redhat.com>
CC: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-09-05 19:06:48 +02:00
Pavel Butsykin
e1b5c51f4c qemu-iotests: test backup compression in 055
Added cases to check the backup compression out of qcow2, raw in qcow2
on drive-backup and blockdev-backup.

Signed-off-by: Pavel Butsykin <pbutsykin@virtuozzo.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Denis V. Lunev <den@openvz.org>
CC: Jeff Cody <jcody@redhat.com>
CC: Markus Armbruster <armbru@redhat.com>
CC: Eric Blake <eblake@redhat.com>
CC: John Snow <jsnow@redhat.com>
CC: Stefan Hajnoczi <stefanha@redhat.com>
CC: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-09-05 19:06:48 +02:00
Kevin Wolf
0524e93a3f block: Accept node-name for drive-mirror
In order to remove the necessity to use BlockBackend names in the
external API, we want to allow node-names everywhere. This converts
drive-mirror to accept a node-name without lifting the restriction that
we're operating at a root node.

In case of an invalid device name, the command returns the GenericError
error class now instead of DeviceNotFound, because this is what
qmp_get_root_bs() returns.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
2016-09-05 19:06:47 +02:00
Kevin Wolf
b7e4fa2242 block: Accept node-name for drive-backup
In order to remove the necessity to use BlockBackend names in the
external API, we want to allow node-names everywhere. This converts
drive-backup and the corresponding transaction action to accept a
node-name without lifting the restriction that we're operating at a root
node.

In case of an invalid device name, the command returns the GenericError
error class now instead of DeviceNotFound, because this is what
qmp_get_root_bs() returns.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
2016-09-05 19:06:47 +02:00
Kevin Wolf
75dfd402a7 block: Accept node-name for blockdev-snapshot-internal-sync
In order to remove the necessity to use BlockBackend names in the
external API, we want to allow node-names everywhere. This converts
blockdev-snapshot-internal-sync to accept a node-name without lifting
the restriction that we're operating at a root node.

In case of an invalid device name, the command returns the GenericError
error class now instead of DeviceNotFound, because this is what
qmp_get_root_bs() returns.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
2016-09-05 19:06:47 +02:00
Kevin Wolf
2dfb4c033f block: Accept node-name for blockdev-snapshot-delete-internal-sync
In order to remove the necessity to use BlockBackend names in the
external API, we want to allow node-names everywhere. This converts
blockdev-snapshot-delete-internal-sync to accept a node-name without
lifting the restriction that we're operating at a root node.

In case of an invalid device name, the command returns the GenericError
error class now instead of DeviceNotFound, because this is what
qmp_get_root_bs() returns.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
2016-09-05 19:06:47 +02:00
Kevin Wolf
b6c1bae5df block: Accept node-name for block-stream
In order to remove the necessity to use BlockBackend names in the
external API, we want to allow node-names everywhere. This converts
block-stream to accept a node-name without lifting the restriction that
we're operating at a root node.

In case of an invalid device name, the command returns the GenericError
error class now instead of DeviceNotFound, because this is what
qmp_get_root_bs() returns.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
2016-09-05 19:06:47 +02:00
Max Reitz
7d3e693646 iotests: Test case for wrong runtime option types
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-08-15 15:52:29 +02:00
Vladimir Sementsov-Ogievskiy
a752e4786c iotests: fix 109
109 iotest is broken for raw after 0965a41e99
[mirror: double performance of the bulk stage if the disc is full]

The problem is with finishing block-job with error: before specified
patch mirror was not very async and it created one big request at disk
start, this request finished with error and qemu produced
BLOCK_JOB_COMPLETED with zero progress.

After 0965a41, mirror starts several smaller requests in parallel, when
BLOCK_JOB_COMPLETED emited we have some successful non-zero progress.

This patch solves the issue by filtering out progress from 109 test
output.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-08-08 13:05:43 +02:00
Daniel P. Berrange
4c44b4a4c8 iotest: fix python based IO tests
The previous commit refactoring iotests.py:

  commit 6661397446
  Author: Daniel P. Berrange <berrange@redhat.com>
  Date:   Wed Jul 20 14:23:10 2016 +0100

    scripts: refactor the VM class in iotests for reuse

was not properly tested and included a number of broken
bits.

 - The 'event_match' method was not moved into qemu.py
 - The 'self._args' list parameter in QEMUMachine needs
   to be copied otherwise modifications will affect the
   global 'qemu_opts' variable in iotests.py
 - The QEMUQtestMachine class methods had inverted
   parameter order for the super() calls
 - The QEMUQtestMachine class forgot to add
   '-machine accel=qtest'
 - The QEMUQtestMachine class constructor needs to set
   a default 'name' value before using it as it may
   be None
 - The QEMUQtestMachine class constructor needs to use
   named parameters when calling the super constructor
   as it is leaving out some positional parameters.
 - The 'qemu_prog' variable should be a string not a
   list in iotests.py
 - The VM classs constructor needs to use named
   parameters when calling the super constructor
   as it is leaving out some positional parameters.
 - The path to the socket-scm-helper needs to be
   passed into the QEMUMachine class

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 1469549767-27249-1-git-send-email-berrange@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
2016-07-26 18:28:40 +02:00
Daniel P. Berrange
6661397446 scripts: refactor the VM class in iotests for reuse
The iotests module has a python class for controlling QEMU
processes. Pull the generic functionality out of this file
and create a scripts/qemu.py module containing a QEMUMachine
class. Put the QTest integration support into a subclass
QEMUQtestMachine.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1469020993-29426-4-git-send-email-berrange@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-07-22 13:23:24 +05:30
Evgeny Yakovlev
3ff2f67a7c block: ignore flush requests when storage is clean
Some guests (win2008 server for example) do a lot of unnecessary
flushing when underlying media has not changed. This adds additional
overhead on host when calling fsync/fdatasync.

This change introduces a write generation scheme in BlockDriverState.
Current write generation is checked against last flushed generation to
avoid unnessesary flushes.

The problem with excessive flushing was found by a performance test
which does parallel directory tree creation (from 2 processes).
Results improved from 0.424 loops/sec to 0.432 loops/sec.
Each loop creates 10^3 directories with 10 files in each.

This affected some blkdebug testcases that were expecting error logs from
failure-injected flushes which are now skipped entirely
(tests 026 071 089).

This also affects the performance of block jobs and thus BLOCK_JOB_READY
events for driver-mirror and active block-commit commands now arrives
faster, before QMP send successfully returns to caller (tests 141 144).

Signed-off-by: Evgeny Yakovlev <eyakovlev@virtuozzo.com>
Signed-off-by: Denis V. Lunev <den@openvz.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-id: 1468870792-7411-5-git-send-email-den@openvz.org
CC: Kevin Wolf <kwolf@redhat.com>
CC: Max Reitz <mreitz@redhat.com>
CC: Stefan Hajnoczi <stefanha@redhat.com>
CC: Fam Zheng <famz@redhat.com>
CC: John Snow <jsnow@redhat.com>
Signed-off-by: John Snow <jsnow@redhat.com>
2016-07-18 18:19:01 -04:00
Max Reitz
42190dcc70 iotests: Make 157 actually format-agnostic
iotest 157 pretends not to care about the image format used, but in fact
it does due to the format name not being filtered in its output. This
patch adds filtering and changes the reference output accordingly.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-id: 20160711132246.3152-1-mreitz@redhat.com
Reviewed-by: John Snow <jsnow@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2016-07-13 13:41:39 +02:00
Alberto Garcia
435d5ee6cd qemu-iotests: Test naming of throttling groups
Throttling groups are named using the 'group' parameter of the
block_set_io_throttle command and the throttling.group command-line
option. If that parameter is unspecified the groups get the name of
the block device.

This patch adds a new test to check the naming of throttling groups.

Signed-off-by: Alberto Garcia <berto@igalia.com>
Message-id: d87d02823a6b91609509d8bb18e2f5dbd9a6102c.1467986342.git.berto@igalia.com
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2016-07-13 13:41:39 +02:00
Kevin Wolf
62ed9fa991 qemu-iotests: Test setting WCE with qdev
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
2016-07-13 13:32:27 +02:00
Daniel P. Berrange
8b7cdba386 crypto: fix handling of iv generator hash defaults
When opening an existing LUKS volume, if the iv generator is
essiv, then the iv hash algorithm is mandatory to provide. We
must report an error if it is omitted in the cipher mode spec,
not silently default to hash 0 (md5).  If the iv generator is
not essiv, then we explicitly ignore any iv hash algorithm,
rather than report an error, for compatibility with dm-crypt.

When creating a new LUKS volume, if the iv generator is essiv
and no iv hsah algorithm is provided, we should default to
using the sha256 hash.

Reported-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2016-07-04 10:46:59 +01:00
John Snow
ccee3d8f97 iotests: add small-granularity mirror test
Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Message-id: 1466625064-11280-4-git-send-email-jsnow@redhat.com
Signed-off-by: Jeff Cody <jcody@redhat.com>
2016-06-28 22:53:03 -04:00
Max Reitz
3dd48fdc55 iotests: Add test for oVirt-like storage migration
Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-id: 20160610185750.30956-6-mreitz@redhat.com
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2016-06-16 15:20:37 +02:00
Max Reitz
298c6009dc iotests: Add test for post-mirror backing chains
Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-id: 20160610185750.30956-5-mreitz@redhat.com
Reviewed-by: Fam Zheng <famz@redhat.com>
[mreitz@redhat.com: Removed unnecessary imports]
Signed-off-by: Max Reitz <mreitz@redhat.com>
2016-06-16 15:20:37 +02:00
Fam Zheng
6ea66b590c iotests: 095: Clean up QEMU before showing image info
Signed-off-by: Fam Zheng <famz@redhat.com>
Message-id: 1464944872-24484-1-git-send-email-famz@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
2016-06-16 15:20:37 +02:00
Thomas Huth
48bea96572 doc: Fix mailing list address in tests/qemu-iotests/README
The address of the mailing list is qemu-devel@nongnu.org
instead of qemu-devel@savannah.nongnu.org. And while we're
at it, also mention the qemu-block mailing list here.

Signed-off-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-06-16 15:19:55 +02:00
Daniel P. Berrange
8c0dcbc4ad block: drop support for using qcow[2] encryption with system emulators
Back in the 2.3.0 release we declared qcow[2] encryption as
deprecated, warning people that it would be removed in a future
release.

  commit a1f688f415
  Author: Markus Armbruster <armbru@redhat.com>
  Date:   Fri Mar 13 21:09:40 2015 +0100

    block: Deprecate QCOW/QCOW2 encryption

The code still exists today, but by a (happy?) accident we entirely
broke the ability to use qcow[2] encryption in the system emulators
in the 2.4.0 release due to

  commit 8336aafae1
  Author: Daniel P. Berrange <berrange@redhat.com>
  Date:   Tue May 12 17:09:18 2015 +0100

    qcow2/qcow: protect against uninitialized encryption key

This commit was designed to prevent future coding bugs which
might cause QEMU to read/write data on an encrypted block
device in plain text mode before a decryption key is set.

It turns out this preventative measure was a little too good,
because we already had a long standing bug where QEMU read
encrypted data in plain text mode during system emulator
startup, in order to guess disk geometry:

  Thread 10 (Thread 0x7fffd3fff700 (LWP 30373)):
  #0  0x00007fffe90b1a28 in raise () at /lib64/libc.so.6
  #1  0x00007fffe90b362a in abort () at /lib64/libc.so.6
  #2  0x00007fffe90aa227 in __assert_fail_base () at /lib64/libc.so.6
  #3  0x00007fffe90aa2d2 in  () at /lib64/libc.so.6
  #4  0x000055555587ae19 in qcow2_co_readv (bs=0x5555562accb0, sector_num=0, remaining_sectors=1, qiov=0x7fffffffd260) at block/qcow2.c:1229
  #5  0x000055555589b60d in bdrv_aligned_preadv (bs=bs@entry=0x5555562accb0, req=req@entry=0x7fffd3ffea50, offset=offset@entry=0, bytes=bytes@entry=512, align=align@entry=512, qiov=qiov@entry=0x7fffffffd260, flags=0) at block/io.c:908
  #6  0x000055555589b8bc in bdrv_co_do_preadv (bs=0x5555562accb0, offset=0, bytes=512, qiov=0x7fffffffd260, flags=<optimized out>) at block/io.c:999
  #7  0x000055555589c375 in bdrv_rw_co_entry (opaque=0x7fffffffd210) at block/io.c:544
  #8  0x000055555586933b in coroutine_thread (opaque=0x555557876310) at coroutine-gthread.c:134
  #9  0x00007ffff64e1835 in g_thread_proxy (data=0x5555562b5590) at gthread.c:778
  #10 0x00007ffff6bb760a in start_thread () at /lib64/libpthread.so.0
  #11 0x00007fffe917f59d in clone () at /lib64/libc.so.6

  Thread 1 (Thread 0x7ffff7ecab40 (LWP 30343)):
  #0  0x00007fffe91797a9 in syscall () at /lib64/libc.so.6
  #1  0x00007ffff64ff87f in g_cond_wait (cond=cond@entry=0x555555e085f0 <coroutine_cond>, mutex=mutex@entry=0x555555e08600 <coroutine_lock>) at gthread-posix.c:1397
  #2  0x00005555558692c3 in qemu_coroutine_switch (co=<optimized out>) at coroutine-gthread.c:117
  #3  0x00005555558692c3 in qemu_coroutine_switch (from_=0x5555562b5e30, to_=to_@entry=0x555557876310, action=action@entry=COROUTINE_ENTER) at coroutine-gthread.c:175
  #4  0x0000555555868a90 in qemu_coroutine_enter (co=0x555557876310, opaque=0x0) at qemu-coroutine.c:116
  #5  0x0000555555859b84 in thread_pool_completion_bh (opaque=0x7fffd40010e0) at thread-pool.c:187
  #6  0x0000555555859514 in aio_bh_poll (ctx=ctx@entry=0x5555562953b0) at async.c:85
  #7  0x0000555555864d10 in aio_dispatch (ctx=ctx@entry=0x5555562953b0) at aio-posix.c:135
  #8  0x0000555555864f75 in aio_poll (ctx=ctx@entry=0x5555562953b0, blocking=blocking@entry=true) at aio-posix.c:291
  #9  0x000055555589c40d in bdrv_prwv_co (bs=bs@entry=0x5555562accb0, offset=offset@entry=0, qiov=qiov@entry=0x7fffffffd260, is_write=is_write@entry=false, flags=flags@entry=(unknown: 0)) at block/io.c:591
  #10 0x000055555589c503 in bdrv_rw_co (bs=bs@entry=0x5555562accb0, sector_num=sector_num@entry=0, buf=buf@entry=0x7fffffffd2e0 "\321,", nb_sectors=nb_sectors@entry=21845, is_write=is_write@entry=false, flags=flags@entry=(unknown: 0)) at block/io.c:614
  #11 0x000055555589c562 in bdrv_read_unthrottled (nb_sectors=21845, buf=0x7fffffffd2e0 "\321,", sector_num=0, bs=0x5555562accb0) at block/io.c:622
  #12 0x000055555589c562 in bdrv_read_unthrottled (bs=0x5555562accb0, sector_num=sector_num@entry=0, buf=buf@entry=0x7fffffffd2e0 "\321,", nb_sectors=nb_sectors@entry=21845) at block/io.c:634
    nb_sectors@entry=1) at block/block-backend.c:504
  #14 0x0000555555752e9f in guess_disk_lchs (blk=blk@entry=0x5555562a5290, pcylinders=pcylinders@entry=0x7fffffffd52c, pheads=pheads@entry=0x7fffffffd530, psectors=psectors@entry=0x7fffffffd534) at hw/block/hd-geometry.c:68
  #15 0x0000555555752ff7 in hd_geometry_guess (blk=0x5555562a5290, pcyls=pcyls@entry=0x555557875d1c, pheads=pheads@entry=0x555557875d20, psecs=psecs@entry=0x555557875d24, ptrans=ptrans@entry=0x555557875d28) at hw/block/hd-geometry.c:133
  #16 0x0000555555752b87 in blkconf_geometry (conf=conf@entry=0x555557875d00, ptrans=ptrans@entry=0x555557875d28, cyls_max=cyls_max@entry=65536, heads_max=heads_max@entry=16, secs_max=secs_max@entry=255, errp=errp@entry=0x7fffffffd5e0) at hw/block/block.c:71
  #17 0x0000555555799bc4 in ide_dev_initfn (dev=0x555557875c80, kind=IDE_HD) at hw/ide/qdev.c:174
  #18 0x0000555555768394 in device_realize (dev=0x555557875c80, errp=0x7fffffffd640) at hw/core/qdev.c:247
  #19 0x0000555555769a81 in device_set_realized (obj=0x555557875c80, value=<optimized out>, errp=0x7fffffffd730) at hw/core/qdev.c:1058
  #20 0x00005555558240ce in property_set_bool (obj=0x555557875c80, v=<optimized out>, opaque=0x555557875de0, name=<optimized out>, errp=0x7fffffffd730)
        at qom/object.c:1514
  #21 0x0000555555826c87 in object_property_set_qobject (obj=obj@entry=0x555557875c80, value=value@entry=0x55555784bcb0, name=name@entry=0x55555591cb3d "realized", errp=errp@entry=0x7fffffffd730) at qom/qom-qobject.c:24
  #22 0x0000555555825760 in object_property_set_bool (obj=obj@entry=0x555557875c80, value=value@entry=true, name=name@entry=0x55555591cb3d "realized", errp=errp@entry=0x7fffffffd730) at qom/object.c:905
  #23 0x000055555576897b in qdev_init_nofail (dev=dev@entry=0x555557875c80) at hw/core/qdev.c:380
  #24 0x0000555555799ead in ide_create_drive (bus=bus@entry=0x555557629630, unit=unit@entry=0, drive=0x5555562b77e0) at hw/ide/qdev.c:122
  #25 0x000055555579a746 in pci_ide_create_devs (dev=dev@entry=0x555557628db0, hd_table=hd_table@entry=0x7fffffffd830) at hw/ide/pci.c:440
  #26 0x000055555579b165 in pci_piix3_ide_init (bus=<optimized out>, hd_table=0x7fffffffd830, devfn=<optimized out>) at hw/ide/piix.c:218
  #27 0x000055555568ca55 in pc_init1 (machine=0x5555562960a0, pci_enabled=1, kvmclock_enabled=<optimized out>) at /home/berrange/src/virt/qemu/hw/i386/pc_piix.c:256
  #28 0x0000555555603ab2 in main (argc=<optimized out>, argv=<optimized out>, envp=<optimized out>) at vl.c:4249

So the safety net is correctly preventing QEMU reading cipher
text as if it were plain text, during startup and aborting QEMU
to avoid bad usage of this data.

For added fun this bug only happens if the encrypted qcow2
file happens to have data written to the first cluster,
otherwise the cluster won't be allocated and so qcow2 would
not try the decryption routines at all, just return all 0's.

That no one even noticed, let alone reported, this bug that
has shipped in 2.4.0, 2.5.0 and 2.6.0 shows that the number
of actual users of encrypted qcow2 is approximately zero.

So rather than fix the crash, and backport it to stable
releases, just go ahead with what we have warned users about
and disable any use of qcow2 encryption in the system
emulators. qemu-img/qemu-io/qemu-nbd are still able to access
qcow2 encrypted images for the sake of data conversion.

In the future, qcow2 will gain support for the alternative
luks format, but when this happens it'll be using the
'-object secret' infrastructure for getting keys, which
avoids this problematic scenario entirely.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-06-16 15:19:55 +02:00
Eric Blake
74021bc497 block: Switch bdrv_write_zeroes() to byte interface
Rename to bdrv_pwrite_zeroes() to let the compiler ensure we
cater to the updated semantics.  Do the same for bdrv_co_write_zeroes().

Signed-off-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-06-08 10:21:08 +02:00
Eric Blake
ebb718a5c7 qcow2: Catch more unaligned write_zero into zero cluster
is_zero_cluster() and is_zero_cluster_top_locked() are used only
by qcow2_co_write_zeroes().  The former is too broad (we don't
care if the sectors we are about to overwrite are non-zero, only
that all other sectors in the cluster are zero), so it needs to
be called up to twice but with smaller limits - rename it along
with adding the neeeded parameter.  The latter can be inlined for
more compact code.

The testsuite change shows that we now have a sparser top file
when an unaligned write_zeroes overwrites the only portion of
the backing file with data.

Based on a patch proposal by Denis V. Lunev.

CC: Denis V. Lunev <den@openvz.org>
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Denis V. Lunev <den@openvz.org>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-06-08 10:21:08 +02:00
Eric Blake
31ad4fdf91 qemu-iotests: Test one more spot for optimizing write_zeroes
Add another test to 154, showing that we currently allocate a
data cluster in the top layer if any sector of the backing file
was allocated.  The next patch will optimize this case.

Signed-off-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-06-08 10:21:08 +02:00
Denis V. Lunev
443668ca40 block: split write_zeroes always
We should split requests even if they are less than write_zeroes_alignment.
For example we can have the following request:
  offset 62k
  size   4k
  write_zeroes_alignment 64k
The original code sent 1 request covering 2 qcow2 clusters, and resulted
in both clusters being allocated. But by splitting the request, we can
cater to the case where one of the two clusters can be zeroed as a
whole, for only 1 cluster allocated after the operation.

Signed-off-by: Denis V. Lunev <den@openvz.org>
CC: Eric Blake <eblake@redhat.com>
CC: Kevin Wolf <kwolf@redhat.com>
Message-Id: <1463476543-3087-2-git-send-email-den@openvz.org>

[eblake: Avoid exceeding nb_sectors, hoist alignment checks out of
loop, and update testsuite to show that patch works]

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-06-08 10:21:08 +02:00
Peter Lieven
117bc3fa22 block/io: optimize bdrv_co_pwritev for small requests
in a read-modify-write cycle a small request might cause
head and tail to fall into the same aligned block. Currently
QEMU reads the same block twice in this case which is
not necessary.

Signed-off-by: Peter Lieven <pl@kamp.de>
Message-id: 1464607873-28206-1-git-send-email-pl@kamp.de
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-06-07 14:40:51 +01:00
Kevin Wolf
b880481579 mirror: Allow target that already has a BlockBackend
We had to forbid mirroring to a target BDS that already had a BB
attached because the node swapping at job completion would add a second
BB and we didn't support multiple BBs on a single BDS at the time. Now
we do, so we can lift the restriction.

As we allow additional BlockBackends for the target, we must expect
other users to be sending requests. There may no requests be in flight
during the graph modification, so we have to drain those users now.

The core part of this patch is a revert of commit 40365552.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
2016-05-25 19:04:21 +02:00
Eric Blake
37546ff28f qemu-iotests: Fix regression in 136 on aio_read invalid
Commit 093ea232 removed the ability for aio_read and aio_write
to artificially inflate the invalid statistics counters for
block devices, since it no longer flags unaligned offset or
length.  Add 'aio_read -i' and 'aio_write -i' to restore
the ability, and update test 136 to use it.

Reported-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-id: 1463416983-28318-4-git-send-email-eblake@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
2016-05-19 16:56:58 +02:00
Eric Blake
9e28bb26c2 qemu-iotests: Simplify 109 with unaligned qemu-img compare
For some time now, qemu-img compare has been able to compare
unaligned images.  So we no longer need test 109's hack of
resizing to sector boundaries before invoking compare.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 1463416983-28318-3-git-send-email-eblake@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
2016-05-19 16:56:58 +02:00