Like BLOCK_OP_TYPE_BACKUP_SOURCE and BLOCK_OP_TYPE_BACKUP_TARGET,
block-commit involves two asymmetric devices.
This change is not user-visible (yet), because commit only works with
device names.
But once we enable backing reference in blockdev-add, or specifying
node-name in block-commit command, we don't want the user to start two
commit jobs on the same backing chain, which will corrupt things because
of the final bdrv_swap.
Before we have per category blockers, splitting this type is still
better.
[Resolved virtio-blk dataplane conflict by replacing
BLOCK_OP_TYPE_COMMIT with both BLOCK_OP_TYPE_COMMIT_{SOURCE, TARGET}.
They are safe since the block job runs in the same AioContext as the
dataplane IOThread.
--Stefan]
Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This is not needed anymore. The new TLS-based algorithm is adaptive.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Message-id: 1417518350-6167-7-git-send-email-pbonzini@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Mirror and migration use dirty bitmaps for their purposes, and since
commit [block: per caller dirty bitmap] they use their own bitmaps, not
the global one. But they use old functions bdrv_set_dirty and
bdrv_reset_dirty, which change all dirty bitmaps.
Named dirty bitmaps series by Fam and Snow are affected: mirroring and
migration will spoil all (not related to this mirroring or migration)
named dirty bitmaps.
This patch fixes this by adding bdrv_set_dirty_bitmap and
bdrv_reset_dirty_bitmap, which change concrete bitmap. Also, to prevent
such mistakes in future, old functions bdrv_(set,reset)_dirty are made
static, for internal block usage.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@parallels.com>
CC: John Snow <jsnow@redhat.com>
CC: Fam Zheng <famz@redhat.com>
CC: Denis V. Lunev <den@openvz.org>
CC: Stefan Hajnoczi <stefanha@redhat.com>
CC: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Message-id: 1417081246-3593-1-git-send-email-vsementsov@parallels.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
When using a relative backing file name, qemu needs to know the
directory of the top image file. For JSON filenames, such a directory
cannot be easily determined (e.g. how do you determine the directory of
a qcow2 BDS directly on top of a quorum BDS?). Therefore, do not allow
relative filenames for the backing file of BDSs only having a JSON
filename.
Furthermore, BDS::exact_filename should be used whenever possible. If
BDS::filename is not equal to BDS::exact_filename, the former will
always be a JSON object.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Introduce bdrv_get_full_backing_filename_from_filename(), a function
which takes the name of the backed file and a potentially relative
backing filename to produce the full (absolute) backing filename.
Use this function from bdrv_get_full_backing_filename().
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
The bdrv_clear_incoming_migration_all() function has not existed since
commit 7ea2d269cb ("block/migration:
Disable cache invalidate for incoming migration").
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 1418212937-22222-1-git-send-email-stefanha@redhat.com
If vmdk blindly tries to use path_combine() using bs->file->filename as
the base file name, this will result in a bad error message for JSON
file names when calling bdrv_open(). It is better to only try
bs->file->exact_filename; if that is empty, bs->file->filename will be
useless for path_combine() and an error should be emitted (containing
bs->file->filename because desc_file_path (which is
bs->file->exact_filename) is empty).
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Message-id: 1417615043-26174-2-git-send-email-mreitz@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
There are some block drivers which are essential to QEMU and may not be
removed: These are raw, file and qcow2 (as the default non-raw format).
Make their BlockDriver objects public so they can be directly referenced
throughout the block layer without needing to call bdrv_find_format()
and having to deal with an error at runtime, while the real problem
occurred during linking (where raw, file or qcow2 were not linked into
qemu).
Cc: qemu-stable@nongnu.org
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
If the user neglects to specify the image format, QEMU probes the
image to guess it automatically, for convenience.
Relying on format probing is insecure for raw images (CVE-2008-2004).
If the guest writes a suitable header to the device, the next probe
will recognize a format chosen by the guest. A malicious guest can
abuse this to gain access to host files, e.g. by crafting a QCOW2
header with backing file /etc/shadow.
Commit 1e72d3b (April 2008) provided -drive parameter format to let
users disable probing. Commit f965509 (March 2009) extended QCOW2 to
optionally store the backing file format, to let users disable backing
file probing. QED has had a flag to suppress probing since the
beginning (2010), set whenever a raw backing file is assigned.
All of these additions that allow to avoid format probing have to be
specified explicitly. The default still allows the attack.
In order to fix this, commit 79368c8 (July 2010) put probed raw images
in a restricted mode, in which they wouldn't be able to overwrite the
first few bytes of the image so that they would identify as a different
image. If a write to the first sector would write one of the signatures
of another driver, qemu would instead zero out the first four bytes.
This patch was later reverted in commit 8b33d9e (September 2010) because
it didn't get the handling of unaligned qiov members right.
Today's block layer that is based on coroutines and has qiov utility
functions makes it much easier to get this functionality right, so this
patch implements it.
The other differences of this patch to the old one are that it doesn't
silently write something different than the guest requested by zeroing
out some bytes (it fails the request instead) and that it doesn't
maintain a list of signatures in the raw driver (it calls the usual
probe function instead).
Note that this change doesn't introduce new breakage for false positive
cases where the guest legitimately writes data into the first sector
that matches the signatures of an image format (e.g. for nested virt):
These cases were broken before, only the failure mode changes from
corruption after the next restart (when the wrong format is probed) to
failing the problematic write request.
Also note that like in the original patch, the restrictions only apply
if the image format has been guessed by probing. Explicitly specifying a
format allows guests to write anything they like.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 1416497234-29880-8-git-send-email-kwolf@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
The only image format driver that even potentially accesses anything
after 512 bytes in its bdrv_probe() implementation is VMDK, which reads
a plain-text descriptor file. In practice, the field it's looking for
seems to come first and will be well within the first 512 bytes, too.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 1416497234-29880-7-git-send-email-kwolf@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Substitute BlockDriverState by BlockBackend in every globally visible
function provided by nbd.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-id: 1416309679-333-5-git-send-email-mreitz@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This returns the node name of a BDS. Remove the TODO comment and expect
the callers to be explicit.
Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Similar to bdrv_next, this traverses through graph_bdrv_states. Will be
useful to enumerate all the named nodes.
Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
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Merge remote-tracking branch 'remotes/mjt/tags/pull-trivial-patches-2014-11-11' into staging
trivial patches for 2014-11-11
# gpg: Signature made Tue 11 Nov 2014 14:38:39 GMT using RSA key ID A4C3D7DB
# gpg: Good signature from "Michael Tokarev <mjt@tls.msk.ru>"
# gpg: aka "Michael Tokarev <mjt@corpit.ru>"
# gpg: aka "Michael Tokarev <mjt@debian.org>"
* remotes/mjt/tags/pull-trivial-patches-2014-11-11:
block: Fix comment for bdrv_co_get_block_status
sysbus: Correct SYSTEM_BUS(obj) defines
target-i386: cpu: keeping function parameters alignment on new line
xen-hvm: Remove redundant variable 'xstate'
coroutine-sigaltstack: Change jmp_buf to sigjmp_buf
pc-bios: petalogix-s3adsp1800.dtb: Use 'xlnx, xps-ethernetlite-2.00.a' instead of 'xlnx, xps-ethernetlite-2.00.b'
gdbstub: Add a missing case of signal number translation in gdbstub
numa: make 'info numa' take into account hotplugged memory
slirp/smbd: modify/set several parameters in generated smbd.conf
qemu-doc.texi: fix typos in x509 examples
icc_bus: fix typo ICC_BRIGDE -> ICC_BRIDGE
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
It returns more information than binary, fix the comment.
Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
Now that op blockers are in use, we can ensure that no other sources are
generating I/O on a BlockDriverState. Therefore it is possible to drain
requests for a single BDS.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 1413889440-32577-7-git-send-email-stefanha@redhat.com
Block jobs will run in the BlockDriverState's AioContext, which may not
always be the QEMU main loop.
There are some block layer APIs that are either not thread-safe or risk
lock ordering problems. This includes bdrv_unref(), bdrv_close(), and
anything that calls bdrv_drain_all().
The block_job_defer_to_main_loop() API allows a block job to schedule a
function to run in the main loop with the BlockDriverState AioContext
held.
This function will be used to perform cleanup and backing chain
manipulations in block jobs.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 1413889440-32577-6-git-send-email-stefanha@redhat.com
Depending on the changed options and the image format,
bdrv_amend_options() may take a significant amount of time. In these
cases, a way to be informed about the operation's status is desirable.
Since the operation is rather complex and may fundamentally change the
image, implementing it as AIO or a coroutine does not seem feasible. On
the other hand, implementing it as a block job would be significantly
more difficult than a simple callback and would not add benefits other
than progress report to the amending operation, because it should not
actually be run as a block job at all.
A callback may not be very pretty, but it's very easy to implement and
perfectly fits its purpose here.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Benoît Canet <benoit.canet@nodalink.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Message-id: 1414404776-4919-2-git-send-email-mreitz@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
When a block job signals readiness, this is currently reported only
through QMP. If qemu wants to use block jobs for internal tasks, there
needs to be another way to correctly detect when a block job may be
completed.
For this reason, introduce a bool "ready" which is set when the block
job may be completed.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Message-id: 1414159063-25977-6-git-send-email-mreitz@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Implement block_job_complete_sync() by doing the exact same thing as
block_job_cancel_sync() does, only with calling block_job_complete()
instead of block_job_cancel().
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 1414159063-25977-5-git-send-email-mreitz@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
bdrv_make_empty() is currently only called if the current image
represents an external snapshot that has been committed to its base
image; it is therefore unlikely to have internal snapshots. In this
case, bdrv_make_empty() can be greatly sped up by emptying the L1 and
refcount table (while having the dirty flag set, which only works for
compat=1.1) and creating a trivial refcount structure.
If there are snapshots or for compat=0.10, fall back to the simple
implementation (discard all clusters).
[Applied s/clusters/cluster/ typo fix suggested by Eric Blake
--Stefan]
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 1414159063-25977-4-git-send-email-mreitz@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
These functions call their non-0-counterparts and then fill the
allocated buffer with 0 (if the allocation has been successful).
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Move device model attachment / detachment and the BlockDevOps device
model callbacks and their wrappers from BlockDriverState to
BlockBackend.
Wrapper calls in block.c change from
bdrv_dev_FOO_cb(bs, ...)
to
if (bs->blk) {
bdrv_dev_FOO_cb(bs->blk, ...);
}
No change, because both bdrv_dev_change_media_cb() and
bdrv_dev_resize_cb() do nothing when no device model is attached, and
a device model can be attached only when bs->blk.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Much more command code needs conversion. I start with this one
because it's using bdrv_dev_* functions, which I'm about to lift into
BlockBackend.
While there, give bdrv_query_info() internal linkage.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Benoît Canet <benoit.canet@nodalink.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
I'll use it with block backends shortly, and the name is going to fit
badly there. It's a block layer thing anyway, not just a block driver
thing.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
I'll use BlockDriverAIOCB with block backends shortly, and the name is
going to fit badly there. It's a block layer thing anyway, not just a
block driver thing.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
BlockBackend's name space is separate only to keep the initial patches
simple. Time to merge the two.
Retain bdrv_find() and bdrv_get_device_name() for now, to keep this
series manageable.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
device_name[] can become non-empty only in bdrv_new_root() and
bdrv_move_feature_fields(). The latter is used only to undo damage
done by bdrv_swap(). The former is called only by blk_new_with_bs().
Therefore, when a BlockDriverState's device_name[] is non-empty, then
it's been created with a BlockBackend, and vice versa. Furthermore,
blk_new_with_bs() keeps the two names equal.
Therefore, device_name[] is redundant. Eliminate it.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Benoît Canet <benoit.canet@nodalink.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Convenience function blk_new_with_bs() creates a BlockBackend with its
BlockDriverState. Callers have to unref both. The commit after next
will relieve them of the need to unref the BlockDriverState.
Complication: due to the silly way drive_del works, we need a way to
hide a BlockBackend, just like bdrv_make_anon(). To emphasize its
"special" status, give the function a suitably off-putting name:
blk_hide_on_behalf_of_do_drive_del(). Unfortunately, hiding turns the
BlockBackend's name into the empty string. Can't avoid that without
breaking the blk->bs->device_name equals blk->name invariant.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Creating an anonymous BDS can't fail. Make that obvious.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Benoît Canet <benoit.canet@nodalink.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
On a system with a low limit of open files the initialization
of the event notifier could fail and QEMU exits without printing any
error information to the user.
The problem can be easily reproduced by enforcing a low limit of open
files and start QEMU with enough I/O threads to hit this limit.
The same problem raises, without the creation of I/O threads, while
QEMU initializes the main event loop by enforcing an even lower limit of
open files.
This commit adds an error message on failure:
# qemu [...] -object iothread,id=iothread0 -object iothread,id=iothread1
qemu: Failed to initialize event notifier: Too many open files in system
Signed-off-by: Chrysostomos Nanakos <cnanakos@grnet.gr>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Now that all the implementations are converted to asynchronous version
and we can emulate synchronous cancellation with it. Let's drop the
unused member.
Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This is the async version of bdrv_aio_cancel, which doesn't block the
caller. It guarantees that the cb is called either before returning or
some time later.
bdrv_aio_cancel can base on bdrv_aio_cancel_async, later we can convert
all .io_cancel implementations to .io_cancel_async, and the aio_poll is
the common logic. In the end, .io_cancel can be dropped.
Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This will be useful in synchronous cancel emulation with
bdrv_aio_cancel_async.
Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This is the next step for decoupling block accounting functions from
BlockDriverState.
In a future commit the BlockAcctStats structure will be moved from
BlockDriverState to the device models structures.
Note that bdrv_get_stats was introduced so device models can retrieve the
BlockAcctStats structure of a BlockDriverState without being aware of it's
layout.
This function should go away when BlockAcctStats will be embedded in the device
models structures.
CC: Kevin Wolf <kwolf@redhat.com>
CC: Stefan Hajnoczi <stefanha@redhat.com>
CC: Keith Busch <keith.busch@intel.com>
CC: Anthony Liguori <aliguori@amazon.com>
CC: "Michael S. Tsirkin" <mst@redhat.com>
CC: Paolo Bonzini <pbonzini@redhat.com>
CC: Eric Blake <eblake@redhat.com>
CC: Peter Maydell <peter.maydell@linaro.org>
CC: Michael Tokarev <mjt@tls.msk.ru>
CC: John Snow <jsnow@redhat.com>
CC: Markus Armbruster <armbru@redhat.com>
CC: Alexander Graf <agraf@suse.de>
CC: Max Reitz <mreitz@redhat.com>
Signed-off-by: Benoît Canet <benoit.canet@nodalink.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
The middle term goal is to move the BlockAcctStats structure in the device models.
(Capturing I/O accounting statistics in the device models is good for billing)
This patch make a small step in this direction by removing a reference to BDRV.
CC: Kevin Wolf <kwolf@redhat.com>
CC: Stefan Hajnoczi <stefanha@redhat.com>
CC: Keith Busch <keith.busch@intel.com>
CC: Anthony Liguori <aliguori@amazon.com>
CC: "Michael S. Tsirkin" <mst@redhat.com>
CC: Paolo Bonzini <pbonzini@redhat.com>
CC: John Snow <jsnow@redhat.com>
CC: Richard Henderson <rth@twiddle.net>
CC: Markus Armbruster <armbru@redhat.com>
CC: Alexander Graf <agraf@suse.de>i
Signed-off-by: Benoît Canet <benoit.canet@nodalink.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
The plan is to add new accounting metrics (latency, invalid requests, failed
requests, queue depth) and block.c is overpopulated so it will be better to work
in a separate module.
Moreover the long term plan is to have statistics in each of the BDS of the graph
for metrology purpose; this means that the device model statistics must move from
the topmost BDS to the device model.
So we need to decouple the statistic code from BlockDriverState.
This is another argument for the extraction of the code in a separate module.
CC: Kevin Wolf <kwolf@redhat.com>
CC: Stefan Hajnoczi <stefanha@redhat.com>
CC: Max Reitz <mreitz@redhat.com>
CC: Eric Blake <eblake@redhat.com>
CC: Benoit Canet <benoit@irqsave.net>
CC: Fam Zheng <famz@redhat.com>
CC: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
CC: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Benoît Canet <benoit.canet@nodalink.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Extract the block accounting statistics into a structure so the block device
models can hold them in the future.
CC: Kevin Wolf <kwolf@redhat.com>
CC: Stefan Hajnoczi <stefanha@redhat.com>
CC: Max Reitz <mreitz@redhat.com>
CC: Eric Blake <eblake@redhat.com>
Signed-off-by: Benoît Canet <benoit.canet@nodalink.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Dragging block_int.h into a header is *not* nice. Fortunately, this
is the only offender.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
If a long-running operation on a BDS wants to always remain in the same
AIO context, it somehow needs to keep track of the BDS changing its
context. This adds a function for registering callbacks on a BDS which
are called whenever the BDS is attached or detached from an AIO context.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Uses the same select/WSAEventSelect scheme as main-loop.c.
WSAEventSelect() is edge-triggered, so it cannot be used
directly, but it is still used as a way to exit from a
blocking g_poll().
Before g_poll() is called, we poll sockets with a non-blocking
select() to achieve the level-triggered semantics we require:
if a socket is ready, the g_poll() is made non-blocking too.
Based on a patch from Or Goshen.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This will be used to implement socket polling on Windows.
On Windows, select() and g_poll() are completely different;
sockets are polled with select() before calling g_poll,
and the g_poll must be nonblocking if select() says a
socket is ready.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
So far, aio_poll's scheme was dispatch/poll/dispatch, where
the first dispatch phase was used only in the GSource case in
order to avoid a blocking poll. Earlier patches changed it to
dispatch/prepare/poll/dispatch, where prepare is aio_compute_timeout.
By making aio_dispatch public, we can remove the first dispatch
phase altogether, so that both aio_poll and the GSource use the same
prepare/poll/dispatch scheme.
This patch breaks the invariant that aio_poll(..., true) will not block
the first time it returns false. This used to be fundamental for
qemu_aio_flush's implementation as "while (qemu_aio_wait()) {}" but
no code in QEMU relies on this invariant anymore. The return value
of aio_poll() is now comparable with that of g_main_context_iteration.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Right now, QEMU invokes aio_bh_poll before the "poll" phase
of aio_poll. It is simpler to do it afterwards and skip the
"poll" phase altogether when the OS-dependent parts of AioContext
are invoked from GSource. This way, AioContext behaves more
similarly when used as a GSource vs. when used as stand-alone.
As a start, take bottom halves into account when computing the
poll timeout. If a bottom half is ready, do a non-blocking
poll. As a side effect, this makes idle bottom halves work
with aio_poll; an improvement, but not really an important
one since they are deprecated.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
block_job_sleep_ns is the only user. Since we are moving towards
AioContext aware code, it's better to use the explicit version and drop
the old one.
Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Benoît Canet <benoit.canet@nodalink.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Some block devices may not have a filename in their BDS; and for some,
there may not even be a normal filename at all. To work around this, add
a function which tries to construct a valid filename for the
BDS.filename field.
If a filename exists or a block driver is able to reconstruct a valid
filename (which is placed in BDS.exact_filename), this can directly be
used.
If no filename can be constructed, we can still construct an options
QDict which is then converted to a JSON object and prefixed with the
"json:" pseudo protocol prefix. The QDict is placed in
BDS.full_open_options.
For most block drivers, this process can be done automatically; those
that need special handling may define a .bdrv_refresh_filename() method
to fill BDS.exact_filename and BDS.full_open_options themselves.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This function returns NULL instead of aborting when an allocation fails.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Benoit Canet <benoit@irqsave.net>
Allow coroutine users to adjust the pool size. For example, if the
guest has multiple emulated disk drives we should keep around more
coroutines.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
A call to retrieve the image size converts between bytes and sectors
several times:
* BlockDriver method bdrv_getlength() returns bytes.
* refresh_total_sectors() converts to sectors, rounding up, and stores
in total_sectors.
* bdrv_getlength() converts total_sectors back to bytes (now rounded
up to a multiple of the sector size).
* Callers wanting sectors rather bytes convert it right back.
Example: bdrv_get_geometry().
bdrv_nb_sectors() provides a way to omit the last two conversions.
It's exactly bdrv_getlength() with the conversion to bytes omitted.
It's functionally like bdrv_get_geometry() without its odd error
handling.
Reimplement bdrv_getlength() and bdrv_get_geometry() on top of
bdrv_nb_sectors().
The next patches will convert some users of bdrv_getlength() to
bdrv_nb_sectors().
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Benoit Canet <benoit@irqsave.net>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Currently, whenever aio_poll(ctx, true) has completed all pending
work it returns true *and* the next call to aio_poll(ctx, true)
will not block.
This invariant has its roots in qemu_aio_flush()'s implementation
as "while (qemu_aio_wait()) {}". However, qemu_aio_flush() does
not exist anymore and bdrv_drain_all() is implemented differently;
and this invariant is complicated to maintain and subtly different
from the return value of GMainLoop's g_main_context_iteration.
All calls to aio_poll(ctx, true) except one are guarded by a
while() loop checking for a request to be incomplete, or a
BlockDriverState to be idle. The one remaining call (in
iothread.c) uses this to delay the aio_context_release/acquire
pair until the AioContext is quiescent, however:
- we can do the same just by using non-blocking aio_poll,
similar to how vl.c invokes main_loop_wait
- it is buggy, because it does not ensure that the AioContext
is released between an aio_notify and the next time the
iothread goes to sleep. This leads to hangs when stopping
the dataplane thread.
In the end, these semantics are a bad match for the current
users of AioContext. So modify that one exception in iothread.c,
which also fixes the hangs, as well as the testcase so that
it use the same idiom as the actual QEMU code.
Reported-by: Christian Borntraeger <borntraeger@de.ibm.com>
Tested-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
In many cases, the call to event_notifier_set in aio_notify is unnecessary.
In particular, if we are executing aio_dispatch, or if aio_poll is not
blocking, we know that we will soon get to the next loop iteration (if
necessary); the thread that hosts the AioContext's event loop does not
need any nudging.
The patch includes a Promela formal model that shows that this really
works and does not need any further complication such as generation
counts. It needs a memory barrier though.
The generation counts are not needed because any change to
ctx->dispatching after the memory barrier is okay for aio_notify.
If it changes from zero to one, it is the right thing to skip
event_notifier_set. If it changes from one to zero, the
event_notifier_set is unnecessary but harmless.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
The main AioContext should be accessed explicitly via qemu_get_aio_context().
Most of the time, using it is not the right thing to do.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This patch introduces three APIs so that following
patches can support queuing I/O requests and submitting them
as a batch for improving I/O performance.
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
On some image chains, QEMU may not always be able to resolve the
filenames properly, when updating the backing file of an image
after a block commit.
For instance, certain relative pathnames may fail, or drives may
have been specified originally by file descriptor (e.g. /dev/fd/???),
or a relative protocol pathname may have been used.
In these instances, QEMU may lack the information to be able to make
the correct choice, but the user or management layer most likely does
have that knowledge.
With this extension to the block-commit api, the user is able to change
the backing file of the overlay image as part of the block-commit
operation.
This allows the change to be 'safe', in the sense that if the attempt
to write the overlay image metadata fails, then the block-commit
operation returns failure, without disrupting the guest.
If the commit top is the active layer, then specifying the backing
file string will be treated as an error (there is no overlay image
to modify in that case).
If a backing file string is not specified in the command, the backing
file string to use is determined in the same manner as it was
previously.
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This is a small helper function, to determine if 'base' is in the
chain of BlockDriverState 'top'. It returns true if it is in the chain,
and false otherwise.
If either argument is NULL, it will also return false.
Reviewed-by: Benoit Canet <benoit@irqsave.net>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Add 'nocow' option so that users could have a chance to set NOCOW flag to
newly created files. It's useful on btrfs file system to enhance performance.
Btrfs has low performance when hosting VM images, even more when the guest
in those VM are also using btrfs as file system. One way to mitigate this bad
performance is to turn off COW attributes on VM files. Generally, there are
two ways to turn off NOCOW on btrfs: a) by mounting fs with nodatacow, then
all newly created files will be NOCOW. b) per file. Add the NOCOW file
attribute. It could only be done to empty or new files.
This patch tries the second way, according to the option, it could add NOCOW
per file.
For most block drivers, since the create file step is in raw-posix.c, so we
can do setting NOCOW flag ioctl in raw-posix.c only.
But there are some exceptions, like block/vpc.c and block/vdi.c, they are
creating file by calling qemu_open directly. For them, do the same setting
NOCOW flag ioctl work in them separately.
[Fixed up 082.out due to the new 'nocow' creation option
--Stefan]
Signed-off-by: Chunyan Liu <cyliu@suse.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
* remotes/bonzini/nbd-next:
nbd: Handle NBD_OPT_LIST option.
nbd: Handle fixed new-style clients.
nbd: Shutdown socket before closing.
nbd: Don't validate from and len in NBD_CMD_DISC.
nbd: Don't export a block device with no medium.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
When this flag is set, the server tells the client that it can send another
option if the server received a request with an option that it doesn't
understand instead of directly closing the connection.
Also add link to the most up-to-date documentation.
Signed-off-by: Hani Benhabiles <kroosec@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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Merge remote-tracking branch 'remotes/kevin/tags/for-upstream' into staging
Block patches for 2.1.0-rc0
# gpg: Signature made Fri 27 Jun 2014 19:50:32 BST using RSA key ID C88F2FD6
# gpg: Good signature from "Kevin Wolf <kwolf@redhat.com>"
* remotes/kevin/tags/for-upstream: (47 commits)
iotests: Fix 083 for out-of-tree builds
iotests: Drop Python version from 065's Shebang
iotests: Use $PYTHON for Python scripts
iotests: Source common.env
configure: Enable out-of-tree iotests
iotests: Allow out-of-tree run
block.c: Don't return success for bdrv_append_temp_snapshot() failure
qemu-iotests: Add TestRepairQuorum to 041 to test drive-mirror node-name mode.
block: Add replaces argument to drive-mirror
blockjob: Fix recent BLOCK_JOB_ERROR regression
blockjob: Fix recent BLOCK_JOB_READY regression
virtio-blk: Rename complete_request_early to complete_request_vring
virtio-blk: Unify {non-,}dataplane's request handlings
virtio-blk: Schedule BH in the right context
virtio-blk: Export request handling functions to dataplane
virtio-blk: Make request completion function virtual
block: acquire AioContext in qmp_query_blockstats()
block: make bdrv_query_stats() static
virtio-blk: Fix and clean up the in_sg and out_sg check
virtio-blk: Fill in VirtIOBlockReq.out in dataplane code
...
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
When failure occurs, 'ret' need be set, or may return 0 to indicate
success. Previously, an error was set in errp, but 0 was returned
anyway. So let bdrv_append_temp_snapshot() return an error code and
use that for the bdrv_open() return value.
Also, error_propagate() need be called only one time within a function.
Signed-off-by: Chen Gang <gang.chen.5i5j@gmail.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
drive-mirror will bdrv_swap the new BDS named node-name with the one
pointed by replaces when the mirroring is finished.
Signed-off-by: Benoit Canet <benoit@irqsave.net>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This function is only called from block/qapi.c. There is no need to
keep it public.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Fam Zheng <famz@redhat.com>
Tested-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This patch improves docs and address small issues in event
callers.
Signed-off-by: Wenchao Xia <wenchaoqemu@gmail.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Since we parse backing.* options to add a backing file from the command
line when the driver didn't assign one, it has been possible to have a
backing file for e.g. raw images (it just was never accessed).
This is obvious nonsense and should be rejected.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
This will unset busy flag and put coroutine to sleep, can be used to
wait for QMP complete/cancel.
Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Since BLOCK_JOB_COMPLETED, BLOCK_JOB_CANCELLED, BLOCK_JOB_READY are
related, convert them in one patch. The block_job_event_* functions
are used to keep encapsulation of BlockJob structure.
Signed-off-by: Wenchao Xia <wenchaoqemu@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
In order to let event defines use existing types later, instead of
redefine new ones, some old type defines for spice and vnc are changed,
and BlockErrorAction is moved from block.h to qapi schema. Note that
BlockErrorAction is not merged with BlockdevOnError.
At this point, VncInfo is not made a child of VncBasicInfo, because
VncBasicInfo has mandatory fields where VncInfo makes them optional.
Signed-off-by: Wenchao Xia <wenchaoqemu@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
This makes scsi_command_name() public.
This makes use of scsi_command_name() in debug output for scsi-disk and
spapr-vscsi host bus adapter. Before this, SCSI used to print hex numbers
instead of human-friendly strings.
This adds GET_EVENT_STATUS_NOTIFICATION and READ_DISC_INFORMATION to
the list of SCSI commands supported by scsi_command_name().
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Now that all backend drivers are using QemuOpts, remove all
QEMUOptionParameter related codes.
Signed-off-by: Dong Xu Wang <wdongxu@linux.vnet.ibm.com>
Signed-off-by: Chunyan Liu <cyliu@suse.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Change block layer to support both QemuOpts and QEMUOptionParameter.
After this patch, it will change backend drivers one by one. At the end,
QEMUOptionParameter will be removed and only QemuOpts is kept.
Signed-off-by: Dong Xu Wang <wdongxu@linux.vnet.ibm.com>
Signed-off-by: Chunyan Liu <cyliu@suse.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
block_int.h is for block layer and block drivers, other code shouldn't
include it. But similar to bdrv_set_aio_context, bdrv_get_aio_context
should also be accessible from outside of block layer.
Move it.
Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
virtio-blk data-plane now uses the QEMU block layer for I/O. We do not
need raw_get_aio_fd() anymore. It was a layering violation anyway, so
let's get rid of it.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Up until now all BlockDriverState instances have used the QEMU main loop
for fd handlers, timers, and BHs. This is not scalable on SMP guests
and hosts so we need to move to a model with multiple event loops on
different host CPUs.
bdrv_set_aio_context() assigns the AioContext event loop to use for a
particular BlockDriverState. It first detaches the entire
BlockDriverState graph from the current AioContext and then attaches to
the new AioContext.
This function will be used by virtio-blk data-plane to assign a
BlockDriverState to its IOThread AioContext. Make
bdrv_aio_set_context() public since data-plane should not include
block_int.h.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This makes use of op_blocker and blocks all the operations except for
commit target, on each BlockDriverState->backing_hd.
The asserts for op_blocker in bdrv_swap are removed because with this
change, the target of block commit has at least the backing blocker of
its child, so the assertion is not true. Callers should do their check.
Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This is the common but non-trivial steps to assign or change the
backing_hd of BDS.
Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This drops BlockDriverState.in_use with op_blockers:
- Call bdrv_op_block_all in place of bdrv_set_in_use(bs, 1).
- Call bdrv_op_unblock_all in place of bdrv_set_in_use(bs, 0).
- Check bdrv_op_is_blocked() in place of bdrv_in_use(bs).
The specific types are used, e.g. in place of starting block backup,
bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_BACKUP, ...).
There is one exception in block_job_create, where
bdrv_op_blocker_is_empty() is used, because we don't know the operation
type here. This doesn't matter because in a few commits away we will drop
the check and move it to callers that _do_ know the type.
- Check bdrv_op_blocker_is_empty() in place of assert(!bs->in_use).
Note: there is only bdrv_op_block_all and bdrv_op_unblock_all callers at
this moment. So although the checks are specific to op types, this
changes can still be seen as identical logic with previously with
in_use. The difference is error message are improved because of blocker
error info.
Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
BlockDriverState.op_blockers is an array of lists with BLOCK_OP_TYPE_MAX
elements. Each list is a list of blockers of an operation type
(BlockOpType), that marks this BDS as currently blocked for a certain
type of operation with reason errors stored in the list. The rule of
usage is:
* BDS user who wants to take an operation should check if there's any
blocker of the type with bdrv_op_is_blocked().
* BDS user who wants to block certain types of operation, should call
bdrv_op_block (or bdrv_op_block_all to block all types of operations,
which is similar to the existing bdrv_set_in_use()).
* A blocker is only referenced by op_blockers, so the lifecycle is
managed by caller, and shouldn't be lost until unblock, so typically
a caller does these:
- Allocate a blocker with error_setg or similar, call bdrv_op_block()
to block some operations.
- Hold the blocker, do his job.
- Unblock operations that it blocked, with the same reason pointer
passed to bdrv_op_unblock().
- Release the blocker with error_free().
Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Benoit Canet <benoit@irqsave.net>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This adds the enum of all the operations that can be taken on a block
device.
Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Benoit Canet <benoit@irqsave.net>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
this patch tries to optimize zero write requests
by automatically using bdrv_write_zeroes if it is
supported by the format.
This significantly speeds up file system initialization and
should speed zero write test used to test backend storage
performance.
I ran the following 2 tests on my internal SSD with a
50G QCOW2 container and on an attached iSCSI storage.
a) mkfs.ext4 -E lazy_itable_init=0,lazy_journal_init=0 /dev/vdX
QCOW2 [off] [on] [unmap]
-----
runtime: 14secs 1.1secs 1.1secs
filesize: 937M 18M 18M
iSCSI [off] [on] [unmap]
----
runtime: 9.3s 0.9s 0.9s
b) dd if=/dev/zero of=/dev/vdX bs=1M oflag=direct
QCOW2 [off] [on] [unmap]
-----
runtime: 246secs 18secs 18secs
filesize: 51G 192K 192K
throughput: 203M/s 2.3G/s 2.3G/s
iSCSI* [off] [on] [unmap]
----
runtime: 8mins 45secs 33secs
throughput: 106M/s 1.2G/s 1.6G/s
allocated: 100% 100% 0%
* The storage was connected via an 1Gbit interface.
It seems to internally handle writing zeroes
via WRITESAME16 very fast.
Signed-off-by: Peter Lieven <pl@kamp.de>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
bdrv_is_allocated() shouldn't return true for sectors that are
unallocated, but after the end of a short backing file, even though
such sectors are (correctly) marked as containing zeros.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
The immediately visible effect of this patch is that it fixes committing
a temporary snapshot to its backing file. Previously, it would fail with
a "permission denied" error because bdrv_inherited_flags() forced the
backing file to be read-only, ignoring the r/w reopen of bdrv_commit().
The bigger problem this revealed is that the original open flags must
actually only be applied to the temporary snapshot, and the original
image file must be treated as a backing file of the temporary snapshot
and get the right flags for that.
Reported-by: Jan Kiszka <jan.kiszka@web.de>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
If target block driver forces compression, qemu-img convert needs to
write by cluster size as well as "-c" option.
Particularly, this applies for converting to VMDK streamOptimized
format.
Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Instead of having unlink() calls in the generic block layer, where we
aren't even guarateed to have a file name, move them to those block
drivers that are actually used and that always have a filename. Gets us
rid of some #ifdefs as well.
The patch also converts bs->is_temporary to a new BDRV_O_TEMPORARY open
flag so that it is inherited in the protocol layer and the raw-posix and
raw-win32 drivers can unlink the file.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
This patch adds an errp parameter to bdrv_new() and updates all its
callers. The next patches will make use of this in order to check for
duplicate IDs. Most of the callers know that their ID is fine, so they
can simply assert that there is no error.
Behaviour doesn't change with this patch yet as bdrv_new() doesn't
actually assign errors to errp.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
bdrv_getlength could fail, check the return value before using it.
Return NULL and set errno if it fails. Callers are updated to handle
the error case.
Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Since commit 9fd3171a, BDRV_O_SNAPSHOT uses an option QDict to specify
the originally requested image as the backing file of the newly created
temporary snapshot. This means that the filename is stored in
"file.filename", which is an option that is not parsed for protocol
names. Therefore things like -drive file=nbd:localhost:10809 were
broken because it looked for a local file with the literal name
'nbd:localhost:10809'.
This patch changes the way BDRV_O_SNAPSHOT works once again. We now open
the originally requested image as normal, and then do a similar
operation as for live snapshots to put the temporary snapshot on top.
This way, both driver specific options and parsed filenames work.
As a nice side effect, this results in code movement to factor
bdrv_append_temp_snapshot() out. This is a good preparation for moving
its call to drive_init() and friends eventually.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
If it returns an error, the migrated VM will not be started, but qemu
exits with an error message.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Benoit Canet <benoit@irqsave.net>
It can be useful to run an AioContext from a thread which normally does
not "own" the AioContext. For example, request draining can be
implemented by acquiring the AioContext and looping aio_poll() until all
requests have been completed.
The following pattern should work:
/* Event loop thread */
while (running) {
aio_context_acquire(ctx);
aio_poll(ctx, true);
aio_context_release(ctx);
}
/* Another thread */
aio_context_acquire(ctx);
bdrv_read(bs, 0x1000, buf, 1);
aio_context_release(ctx);
This patch implements aio_context_acquire() and aio_context_release().
Note that existing aio_poll() callers do not need to worry about
acquiring and releasing - it is only needed when multiple threads will
call aio_poll() on the same AioContext.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This patch keep the recursive way of doing things but simplify it by giving
two responsabilities to all block filters implementors.
They will need to do two things:
-Set the is_filter field of their block driver to true.
-Implement the bdrv_recurse_is_first_non_filter method of their block driver like
it is done on the Quorum block driver. (block/quorum.c)
[Paolo Bonzini <pbonzini@redhat.com> pointed out that this patch changes
the semantics of blkverify, which now recurses down both bs->file and
s->test_file.
-- Stefan]
Reported-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Benoit Canet <benoit@irqsave.net>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
qemu-nbd is one of the few valid users of qerror_report_err. Move
the error-reporting socket wrappers there.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Before:
$ ./qemu-io-old
qemu-io-old> open -r -o file.driver=nbd
one of path and host must be specified.
qemu-io-old: can't open device (null): Could not open image: Invalid argument
$ ./qemu-io-old
qemu-io-old> open -r -o file.driver=nbd,file.host=foo,file.path=bar
path and host may not be used at the same time.
qemu-io-old: can't open device (null): Could not open image: Invalid argument
After:
$ ./qemu-io
qemu-io> open -r -o file.driver=nbd
qemu-io: can't open device (null): one of path and host must be specified.
$ ./qemu-io
qemu-io> open -r -o file.driver=nbd,file.host=foo,file.path=bar
qemu-io: can't open device (null): path and host may not be used at the same time.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This option is now unnecessary since specifying BDRV_O_PROTOCOL as flag
will do exactly the same.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Benoit Canet <benoit@irqsave.net>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Paolo Bonzini