Commit Graph

220 Commits

Author SHA1 Message Date
Fam Zheng
20a63d2cec commit: Support commit active layer
If active is top, it will be mirrored to base, (with block/mirror.c
code), then the image is switched when user completes the block job.

QMP documentation is updated.

Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-12-20 16:26:16 +01:00
Marc-André Lureau
314f7ea74f qmp_change_blockdev() remove unused has_format
Signed-off-by: Marc-André Lureau <marcandre.lureau@gmail.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
2013-12-16 10:12:20 +01:00
Max Reitz
117e0c8288 block/drive-mirror: Reuse backing HD for sync=none
For "none" sync mode in "absolute-paths" mode, the current image should
be used as the backing file for the newly created image.

The current behavior is:
a) If the image to be mirrored has a backing file, use that (which is
   wrong, since the operations recorded by "none" are applied to the
   image itself, not to its backing file).
b) If the image to be mirrored lacks a backing file, the target doesn't
   have one either (which is not really wrong, but not really right,
   either; "none" records a set of operations executed on the image
   file, therefore having no backing file to apply these operations on
   seems rather pointless).

For a, this is clearly a bugfix. For b, it is still a bugfix, although
it might break existing API - but since that case crashed qemu just
three weeks ago (before 1452686495), we
can safely assume there is no such API relying on that case yet.

Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 1385407736-13941-2-git-send-email-mreitz@redhat.com
Signed-off-by: Anthony Liguori <aliguori@amazon.com>
2013-11-27 07:53:32 -08:00
Amos Kong
968854c8a1 qmp: access the local QemuOptsLists for drive option
Currently we have three QemuOptsList (qemu_common_drive_opts,
qemu_legacy_drive_opts, and qemu_drive_opts), only qemu_drive_opts
is added to vm_config_groups[].

This patch changes query-command-line-options to access three local
QemuOptsLists for drive option, and merge the description items
together.

Signed-off-by: Amos Kong <akong@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-11-14 13:09:07 +01:00
Max Reitz
1452686495 block/drive-mirror: Check for NULL backing_hd
It should be possible to execute the QMP "drive-mirror" command in
"none" sync mode and "absolute-paths" mode even for block devices
lacking a backing file.

"absolute-paths" does in fact not require a backing file to be present,
as can be seen from the "top" sync mode code path. "top" basically
states that the device should indeed have a backing file - however, the
current code catches the case if it doesn't and then simply treats it as
"full" sync mode, creating a target image without a backing file (in
"absolute-paths" mode). Thus, "absolute-paths" does not imply the target
file must indeed have a backing file.

Therefore, the target file may be left unbacked in case of "none" sync
mode as well, if the specified device is not backed either. Currently,
qemu will crash trying to dereference the backing file pointer since it
assumes that it will always be non-NULL in that case ("none" with
"absolute-paths").

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Wenchao Xia <xiawenc@linux.vnet.ibm.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-11-14 13:09:06 +01:00
Stefan Hajnoczi
ec9c10d29c blockdev: fix drive_init() opts and bs_opts leaks
These memory leaks also make drive_add if=none,id=drive0 without a file=
option leak the options list.  This keeps ID "drive0" around forever.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2013-11-07 13:53:31 +01:00
Fam Zheng
a7fdbcf0e6 blockdev: fix cdrom read_only flag
Since 0ebd24e0, cdrom doesn't have read-only on by default, which will
error out when using an read only image. Fix it by setting the default
value when parsing opts.

Reported-by: Edivaldo de Araujo Pereira <edivaldoapereira@yahoo.com.br>
Signed-off-by: Fam Zheng <famz@redhat.com>

Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-10-17 10:19:59 +02:00
Kevin Wolf
b681072d20 blockdev: blockdev_init() error conversion
This gives us meaningful error messages for the blockdev-add QMP
command.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2013-10-11 16:50:02 +02:00
Kevin Wolf
0ebd24e0a2 blockdev: Don't disable COR automatically with blockdev-add
If a read-only device is configured with copy-on-read=on, the old code
only prints a warning and automatically disables copy on read. Make it
a real error for blockdev-add.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2013-10-11 16:50:02 +02:00
Kevin Wolf
e34ef04641 blockdev: Remove 'media' parameter from blockdev_init()
The remaining users shouldn't be there with blockdev-add and are easy to
move to drive_init().

Bonus bug fix: As a side effect, CD-ROM drives can now use block drivers
on the read-only whitelist without explicitly specifying read-only=on,
even if a format is explicitly specified.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2013-10-11 16:50:02 +02:00
Kevin Wolf
4f8a066b5f blockdev: Remove IF_* check for read-only blockdev_init
IF_NONE allows read-only, which makes forbidding it in this place
for other types pretty much pointless.

Instead, make sure that all devices for which the check would have
errored out check in their init function that they don't get a read-only
BlockDriverState. This catches even cases where IF_NONE and -device is
used.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2013-10-11 16:50:01 +02:00
Kevin Wolf
394c7d4d6b blockdev: Move virtio-blk device creation to drive_init
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2013-10-11 16:50:01 +02:00
Kevin Wolf
87a899c509 blockdev: Move bus/unit/index processing to drive_init
This requires moving the automatic ID generation at the same time, so
let's do that as well.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2013-10-11 16:50:01 +02:00
Kevin Wolf
2692929802 blockdev: Move parsing of 'boot' option to drive_init
It's already ignored and only prints a deprecation message. No use in
making it available in new interfaces.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2013-10-11 16:50:01 +02:00
Kevin Wolf
b41a7338cf blockdev: Moving parsing of geometry options to drive_init
This moves all of the geometry options (cyls/heads/secs/trans) to
drive_init so that they can only be accessed using legacy functions, but
never with anything blockdev-add related.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2013-10-11 16:50:01 +02:00
Kevin Wolf
593d464bd4 blockdev: Move parsing of 'if' option to drive_init
It's always IF_NONE for blockdev-add.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Benoit Canet <benoit@irqsave.net>
Reviewed-by: Eric Blake <eblake@redhat.com>
2013-10-11 16:50:01 +02:00
Kevin Wolf
33cb7dc8b7 blockdev: Move parsing of 'media' option to drive_init
This moves as much as possible of the processing of the 'media' option
to drive_init so that it can only be accessed using legacy functions,
but never with anything blockdev-add related.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Benoit Canet <benoit@irqsave.net>
Reviewed-by: Eric Blake <eblake@redhat.com>
2013-10-11 16:50:01 +02:00
Kevin Wolf
f298d07166 blockdev: Pass QDict to blockdev_init()
Working on a QDict instead of a QemuOpts that accepts anything is more
in line with bdrv_open(). A QDict is what qmp_blockdev_add() already has
anyway, so this saves additional conversions. And last, but not least,
it allows later patches to easily extract legacy options into a
separate, typed QemuOpts for drive_init() (the untyped QemuOpts that
drive_init already has doesn't allow access to numbers, only strings,
and is therefore useless without conversion).

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Benoit Canet <benoit@irqsave.net>
Reviewed-by: Eric Blake <eblake@redhat.com>
2013-10-11 16:50:01 +02:00
Kevin Wolf
326642bc7f blockdev: Separate ID generation from DriveInfo creation
blockdev-add shouldn't automatically generate IDs, but will keep most of
the DriveInfo creation code.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Wenchao Xia <xiawenc@linux.vnet.ibm.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2013-10-11 16:50:01 +02:00
Kevin Wolf
d26c9a1573 blockdev: 'blockdev-add' QMP command
For examples see the changes to qmp-commands.hx.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-10-11 16:50:01 +02:00
Kevin Wolf
2d246f01d3 blockdev: Introduce DriveInfo.enable_auto_del
BlockDriverStates shouldn't be affected by an unplugged guest device,
except if created with the legacy -drive command line option or the
drive_add HMP command.

Make the automatic deletion as well as cancelling of jobs conditional on
an enable_auto_del boolean that is only set in drive_init().

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Wenchao Xia <xiawenc@linux.vnet.ibm.com>
2013-10-11 16:50:01 +02:00
Kevin Wolf
8f94a6e40e block: Improve driver whitelist checks
The main intent of this patch is to consolidate the whitelist checks to
a single point in the code instead of spreading it everywhere. This adds
a nicer error message for read-only whitelisting, too, in places where
it was still missing.

The patch also contains a bonus bug fix: By finding the format first in
bdrv_open() and then independently checking against the whitelist only
later, we avoid the case that use of a non-whitelisted format results in
probing rather than an error message. Previously, this could happen when
using the driver=... option.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
2013-10-11 16:50:00 +02:00
Benoît Canet
f6186f49e2 block: Add BlockDriver.bdrv_check_ext_snapshot.
This field is used by blkverify to disable external snapshots creation.
It will also be used by block filters like quorum to disable external
snapshot creation.

Signed-off-by: Benoit Canet <benoit@irqsave.net>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-10-11 16:49:59 +02:00
Stefan Weil
3a6f270326 block: Remove unused assignment (fixes warning from clang)
blockdev.c:1929:13: warning: Value stored to 'ret' is never read
            ret = 0;
            ^     ~

Signed-off-by: Stefan Weil <sw@weilnetz.de>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2013-10-02 22:55:28 +04:00
Paolo Bonzini
1df6fa4bc6 blockdev: do not default cache.no-flush to true
That's why all my VMs were so fast lately. :)

This changed in 1.6.0 by mistake in patch 29c4e2b (blockdev: Split up
'cache' option, 2013-07-18).

Cc: qemu-stable@nongnu.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-09-20 19:27:44 +02:00
Max Reitz
aa3fe714f7 block: Assert validity of BdrvActionOps
In qmp_transaction, assert that the BdrvActionOps to be used is actually
valid.

This assertion failing is very improbable, however, it might happen, if
a new TransactionActionKind is introduced "out of order" and the
actions[] array is not updated.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-09-12 16:28:36 +02:00
Max Reitz
34b5d2c68e block: Error parameter for open functions
Add an Error ** parameter to bdrv_open, bdrv_file_open and associated
functions to allow more specific error messages.

Signed-off-by: Max Reitz <mreitz@redhat.com>
2013-09-12 10:12:48 +02:00
Wenchao Xia
44e3e053af qmp: add interface blockdev-snapshot-delete-internal-sync
This interface use id and name as optional parameters, to handle the
case that one image contain multiple snapshots with same name which
may be '', but with different id.

Adding parameter id is for historical compatiability reason, and
that case is not possible in qemu's new interface for internal
snapshot at block device level, but still possible in qemu-img.

Signed-off-by: Wenchao Xia <xiawenc@linux.vnet.ibm.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-09-12 10:12:47 +02:00
Wenchao Xia
f323bc9e8b qmp: add interface blockdev-snapshot-internal-sync
Snapshot ID can't be specified in this interface.

Signed-off-by: Wenchao Xia <xiawenc@linux.vnet.ibm.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-09-12 10:12:47 +02:00
Wenchao Xia
bbe860104f qmp: add internal snapshot support in qmp_transaction
Unlike savevm, the qmp_transaction interface will not generate
snapshot name automatically, saving trouble to return information
of the new created snapshot.

Although qcow2 support storing multiple snapshots with same name
but different ID, here it will fail when an snapshot with that name
already exist before the operation. Format such as rbd do not support
ID at all, and in most case, it means trouble to user when he faces
multiple snapshots with same name, so ban that case. Request with
empty name will be rejected.

Snapshot ID can't be specified in this interface.

Signed-off-by: Wenchao Xia <xiawenc@linux.vnet.ibm.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-09-12 10:12:47 +02:00
Fam Zheng
fa510ebffa block: use BDS ref for block jobs
Block jobs used drive_get_ref(drive_get_by_blockdev(bs)) to avoid BDS
being deleted. Now we have BDS reference count, and block jobs don't
care about dinfo, so replace them to get cleaner code. It is also the
safe way when BDS has no drive info.

Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-09-06 15:25:08 +02:00
Fam Zheng
4f6fd3491c block: make bdrv_delete() static
Manage BlockDriverState lifecycle with refcnt, so bdrv_delete() is no
longer public and should be called by bdrv_unref() if refcnt is
decreased to 0.

This is an identical change because effectively, there's no multiple
reference of BDS now: no caller of bdrv_ref() yet, only bdrv_new() sets
bs->refcnt to 1, so all bdrv_unref() now actually delete the BDS.

Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-09-06 15:25:08 +02:00
Benoît Canet
2024c1df43 block: Add iops_size to do the iops accounting for a given io size.
This feature can be used in case where users are avoiding the iops limit by
doing jumbo I/Os hammering the storage backend.

Signed-off-by: Benoit Canet <benoit@irqsave.net>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-09-06 15:25:07 +02:00
Benoît Canet
3e9fab690d block: Add support for throttling burst max in QMP and the command line.
The max parameter of the leaky bucket throttling algorithm can be used to
allow the guest to do bursts.
The max value is a pool of I/O that the guest can use without being throttled
at all. Throttling is triggered once this pool is empty.

Signed-off-by: Benoit Canet <benoit@irqsave.net>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-09-06 15:25:07 +02:00
Benoît Canet
cc0681c454 block: Enable the new throttling code in the block layer.
Signed-off-by: Benoit Canet <benoit@irqsave.net>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-09-06 15:25:07 +02:00
Kevin Wolf
c0447d870b Revert "block: Disable driver-specific options for 1.6"
This reverts commit 8afaefb891.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-08-30 15:28:52 +02:00
Alex Bligh
bc72ad6754 aio / timers: Switch entire codebase to the new timer API
This is an autogenerated patch using scripts/switch-timer-api.

Switch the entire code base to using the new timer API.

Note this patch may introduce some line length issues.

Signed-off-by: Alex Bligh <alex@alex.org.uk>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-08-22 19:14:24 +02:00
Fam Zheng
7780d47211 block: better error message for read only format name
When user tries to use read-only whitelist format in the command line
option, failure message was "'foo' invalid format". It might be invalid
only for writable, but valid for read-only, so it is confusing. Give the
user easier to understand information.

Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-08-22 14:30:03 +02:00
M. Mohan Kumar
8b7a5415f9 block: Dont ignore previously set bdrv_flags
bdrv_flags is set by bdrv_parse_discard_flags(), but later it is reset
to zero.

Signed-off-by: M. Mohan Kumar <mohan@in.ibm.com>
Message-id: 1376483201-13466-1-git-send-email-mohan@in.ibm.com
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2013-08-14 08:34:00 -05:00
Mike Qiu
6db5f5d68e block: Bugfix 'format' and 'snapshot' used in drive option
When use -drive file='xxx',format=qcow2,snapshot=on the error
message "Can't use snapshot=on with driver-specific options"
can be show, and fail to start the qemu.

This should not be happened, and there is no file.driver option
in qemu command line.

It is because the commit 74fe54f2a1,
it puts 'driver' option if the command line use 'format' option.

This patch is to solve this bug.

Signed-off-by: Mike Qiu <qiudayu@linux.vnet.ibm.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-08-09 19:33:23 +02:00
Kevin Wolf
8afaefb891 block: Disable driver-specific options for 1.6
We don't want to commit to the API yet before everything is worked out.
Like already for 1.5, disable it again for the 1.6 release. This commit
is meant to be reverted after the 1.6 release.

The disabling of the driver-specific options is achieved by applying the
old checks while parsing the command line.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-08-02 18:21:11 +02:00
Stefan Weil
dfc6f86567 misc: Use g_assert_not_reached for code which is expected to be unreachable
The macro g_assert_not_reached is a better self documenting replacement
for assert(0) or assert(false).

Signed-off-by: Stefan Weil <sw@weilnetz.de>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2013-07-27 11:22:54 +04:00
Ian Main
fc5d3f8432 Implement sync modes for drive-backup.
This patch adds sync-modes to the drive-backup interface and
implements the FULL, NONE and TOP modes of synchronization.

FULL performs as before copying the entire contents of the drive
while preserving the point-in-time using CoW.
NONE only copies new writes to the target drive.
TOP copies changes to the topmost drive image and preserves the
point-in-time using CoW.

For sync mode TOP are creating a new target image using the same backing
file as the original disk image.  Then any new data that has been laid
on top of it since creation is copied in the main backup_run() loop.
There is an extra check in the 'TOP' case so that we don't bother to copy
all the data of the backing file as it already exists in the target.
This is where the bdrv_co_is_allocated() is used to determine if the
data exists in the topmost layer or below.

Also any new data being written is intercepted via the write_notifier
hook which ends up calling backup_do_cow() to copy old data out before
it gets overwritten.

For mode 'NONE' we create the new target image and only copy in the
original data from the disk image starting from the time the call was
made.  This preserves the point in time data by only copying the parts
that are *going to change* to the target image.  This way we can
reconstruct the final image by checking to see if the given block exists
in the new target image first, and if it does not, you can get it from
the original image.  This is basically an optimization allowing you to
do point-in-time snapshots with low overhead vs the 'FULL' version.

Since there is no old data to copy out the loop in backup_run() for the
NONE case just calls qemu_coroutine_yield() which only wakes up after
an event (usually cancel in this case).  The rest is handled by the
before_write notifier which again calls backup_do_cow() to write out
the old data so it can be preserved.

Signed-off-by: Ian Main <imain@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-07-26 22:01:31 +02:00
Kevin Wolf
29c4e2b50d blockdev: Split up 'cache' option
The old 'cache' option really encodes three different boolean flags into
a cache mode name, without providing all combinations. Make them three
separate options instead and translate the old option to the new ones
for drive_init().

The specific boolean options take precedence if the old cache option is
specified as well, so the following options are equivalent:

-drive file=x,cache=none,cache.no-flush=true
-drive file=x,cache.writeback=true,cache.direct=true,cache.no-flush=true

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2013-07-26 22:01:31 +02:00
Kevin Wolf
0f227a9470 blockdev: Rename 'readonly' option to 'read-only'
Option name cleanup before it becomes a QMP API.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2013-07-26 22:01:02 +02:00
Kevin Wolf
57975222b6 blockdev: Rename I/O throttling options for QMP
In QMP, we want to use dashes instead of underscores in QMP argument
names, and use nested options for throttling.

The new option names affect the command line as well, but for
compatibility drive_init() will convert the old option names before
calling into the code that will be shared between -drive and
blockdev-add.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2013-07-26 21:10:11 +02:00
Kevin Wolf
74fe54f2a1 block: Allow "driver" option on the top level
This is traditionally -drive format=..., which is now translated into
the new driver option. This gives us a more consistent way to select the
driver of BlockDriverStates that can be used in QMP context, too.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2013-07-26 21:10:11 +02:00
Stefan Hajnoczi
b53169eae0 blockdev: add sync mode to drive-backup QMP command
The drive-backup command is similar to the drive-mirror command, except
no guest data written after the command executes gets copied.  Add a
sync mode argument which determines whether the entire disk is copied,
just allocated clusters, or only clusters being written to by the guest.

Currently only sync mode 'full' is supported - it copies the entire disk.
For read-only point-in-time snapshots we may only need sync mode 'none'
since the target can be a qcow2 file using the guest's disk as its
backing file (no need to copy the entire disk).  Finally, sync mode
'top' is useful if we wish to preserve the backing chain.

Note that this patch just adds the sync mode argument to drive-backup.
It does not implement sync modes 'top' or 'none'.  This patch is
necessary so we can add a drive-backup HMP command that behaves like the
existing drive-mirror HMP command and takes a sync mode.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-07-15 09:49:00 +02:00
Stefan Hajnoczi
78b18b78aa blockdev: add Abort transaction
The Abort action can be used to test QMP 'transaction' failure.  Add it
as the last action to exercise the .abort() and .cleanup() code paths
for all previous actions.

Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-06-28 09:20:27 +02:00
Stefan Hajnoczi
3037f36446 blockdev: add DriveBackup transaction
This patch adds a transactional version of the drive-backup QMP command.
It allows atomic snapshots of multiple drives along with automatic
cleanup if there is a failure to start one of the backup jobs.

Note that QMP events are emitted for block job completion/cancellation
and the block job will be listed by query-block-jobs.

@device: the name of the device whose writes should be mirrored.

@target: the target of the new image. If the file exists, or if it
         is a device, the existing file/device will be used as the new
         destination.  If it does not exist, a new file will be created.

@format: #optional the format of the new destination, default is to
         probe if @mode is 'existing', else the format of the source

@mode: #optional whether and how QEMU should create a new image, default is
       'absolute-paths'.

@speed: #optional the maximum speed, in bytes per second

@on-source-error: #optional the action to take on an error on the source,
                  default 'report'.  'stop' and 'enospc' can only be used
                  if the block device supports io-status (see BlockInfo).

@on-target-error: #optional the action to take on an error on the target,
                  default 'report' (no limitations, since this applies to
                  a different block device than @device).

Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-06-28 09:20:27 +02:00