The generated qapi_event_send_FOO() take an Error ** argument.  They
can't actually fail, because all they do with the argument is passing it
to functions that can't fail: the QObject output visitor, and the
@qmp_emit callback, which is either monitor_qapi_event_queue() or
event_test_emit().

Drop the argument, and pass &error_abort to the QObject output visitor
and @qmp_emit instead.
Suggested-by: NEric Blake <eblake@redhat.com>
Suggested-by: NMarkus Armbruster <armbru@redhat.com>
Signed-off-by: NPeter Xu <peterx@redhat.com>
Message-Id: <20180815133747.25032-4-peterx@redhat.com>
Reviewed-by: NMarkus Armbruster <armbru@redhat.com>
[Commit message rewritten, update to qapi-code-gen.txt corrected]
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>

We already requested that block jobs be paused in .bdrv_drained_begin,
but no guarantee was made that the job was actually inactive at the
point where bdrv_drained_begin() returned.

This introduces a new callback BdrvChildRole.bdrv_drained_poll() and
uses it to make bdrv_drain_poll() consider block jobs using the node to
be drained.

For the test case to work as expected, we have to switch from
block_job_sleep_ns() to qemu_co_sleep_ns() so that the test job is even
considered active and must be waited for when draining the node.
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

BlockJob.driver is redundant with Job.driver and only used in very few
places any more. Remove it.
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

BlockJob has fields .offset and .len, which are actually misnomers today
because they are no longer tied to block device sizes, but just progress
counters. As such they make a lot of sense in generic Jobs.

This patch moves the fields to Job and renames them to .progress_current
and .progress_total to describe their function better.
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
Reviewed-by: NMax Reitz <mreitz@redhat.com>

The transition to the READY state was still performed in the BlockJob
layer, in the same function that sent the BLOCK_JOB_READY QMP event.

This patch brings the state transition to the Job layer and implements
the QMP event using a notifier called from the Job layer, like we
already do for other events related to state transitions.
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
Reviewed-by: NMax Reitz <mreitz@redhat.com>

Instead of having a 'bool ready' in BlockJob, add a function that
derives its value from the job status.

At the same time, this fixes the behaviour to match what the QAPI
documentation promises for query-block-job: 'true if the job may be
completed'. When the ready flag was introduced in commit ef6dbf1e,
the flag never had to be reset to match the description because after
being ready, the jobs would immediately complete and disappear.

Job transactions and manual job finalisation were introduced only later.
With these changes, jobs may stay around even after having completed
(and they are not ready to be completed a second time), however their
patches forgot to reset the ready flag.
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
Reviewed-by: NMax Reitz <mreitz@redhat.com>

This moves block_job_dismiss() to the Job layer.
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
Reviewed-by: NMax Reitz <mreitz@redhat.com>

This moves block_job_yield() to the Job layer.
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
Reviewed-by: NMax Reitz <mreitz@redhat.com>

This moves the top-level job completion and cancellation functions from
BlockJob to Job.
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

This moves the logic that implements job transactions from BlockJob to
Job.
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
Reviewed-by: NMax Reitz <mreitz@redhat.com>

This doesn't actually move any transaction code to Job yet, but it
renames the type for transactions from BlockJobTxn to JobTxn and makes
them contain Jobs rather than BlockJobs
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
Reviewed-by: NMax Reitz <mreitz@redhat.com>

block_job_finish_sync() doesn't contain anything block job specific any
more, so it can be moved to Job.
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
Reviewed-by: NMax Reitz <mreitz@redhat.com>

This moves the .complete callback that tells a READY job to complete
from BlockJobDriver to JobDriver. The wrapper function job_complete()
doesn't require anything block job specific any more and can be moved
to Job.
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
Reviewed-by: NMax Reitz <mreitz@redhat.com>

block_job_drain() contains a blk_drain() call which cannot be moved to
Job, so add a new JobDriver callback JobDriver.drain which has a common
implementation for all BlockJobs. In addition to this we keep the
existing BlockJobDriver.drain callback that is called by the common
drain implementation for all block jobs.
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
Reviewed-by: NMax Reitz <mreitz@redhat.com>

block_job_cancel_async() did two things that were still block job
specific:

* Setting job->force. This field makes sense on the Job level, so we can
  just move it. While at it, rename it to job->force_cancel to make its
  purpose more obvious.

* Resetting the I/O status. This can't be moved because generic Jobs
  don't have an I/O status. What the function really implements is a
  user resume, except without entering the coroutine. Consequently, it
  makes sense to call the .user_resume driver callback here which
  already resets the I/O status.

  The old block_job_cancel_async() has two separate if statements that
  check job->iostatus != BLOCK_DEVICE_IO_STATUS_OK and job->user_paused.
  However, the former condition always implies the latter (as is
  asserted in block_job_iostatus_reset()), so changing the explicit call
  of block_job_iostatus_reset() on the former condition with the
  .user_resume callback on the latter condition is equivalent and
  doesn't need to access any BlockJob specific state.
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
Reviewed-by: NMax Reitz <mreitz@redhat.com>

This moves the finalisation of a single job from BlockJob to Job.

Some part of this code depends on job transactions, and job transactions
call this code, we introduce some temporary calls from Job functions to
BlockJob ones. This will be fixed once transactions move to Job, too.
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
Reviewed-by: NMax Reitz <mreitz@redhat.com>

Go through the Job layer in order to send QMP events. For the moment,
these functions only call a notifier in the BlockJob layer that sends
the existing commands.

This uses notifiers rather than JobDriver callbacks because internal
users of jobs won't receive QMP events, but might still be interested
in getting notified for the events.
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
Reviewed-by: NMax Reitz <mreitz@redhat.com>

block_job_event_pending() doesn't only send a QMP event, but it also
transitions to the PENDING state. Split the function so that we get one
part only sending the event (like other block_job_event_* functions) and
another part that does the state transition.
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
Reviewed-by: NMax Reitz <mreitz@redhat.com>

This renames the BlockJobCreateFlags constants, moves a few JOB_INTERNAL
checks to job_create() and the auto_{finalize,dismiss} fields from
BlockJob to Job.
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
Reviewed-by: NMax Reitz <mreitz@redhat.com>

Since we introduced an explicit status to block job, BlockJob.completed
is redundant because it can be derived from the status. Remove the field
from BlockJob and add a function to derive it from the status at the Job
level.
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
Reviewed-by: NMax Reitz <mreitz@redhat.com>
Reviewed-by: NJohn Snow <jsnow@redhat.com>

While we already moved the state related to job pausing to Job, the
functions to do were still BlockJob only. This commit moves them over to
Job.
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
Reviewed-by: NMax Reitz <mreitz@redhat.com>
Reviewed-by: NJohn Snow <jsnow@redhat.com>

There is nothing block layer specific about block_job_sleep_ns(), so
move the function to Job.
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
Reviewed-by: NJohn Snow <jsnow@redhat.com>
Reviewed-by: NMax Reitz <mreitz@redhat.com>

This commit moves some core functions for dealing with the job coroutine
from BlockJob to Job. This includes primarily entering the coroutine
(both for the first and reentering) and yielding explicitly and at pause
points.
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
Reviewed-by: NJohn Snow <jsnow@redhat.com>

Move the defer_to_main_loop functionality from BlockJob to Job.

The code can be simplified because we can use job->aio_context in
job_defer_to_main_loop_bh() now, instead of having to access the
BlockDriverState.

Probably taking the data->aio_context lock in addition was already
unnecessary in the old code because we didn't actually make use of
anything protected by the old AioContext except getting the new
AioContext, in case it changed between scheduling the BH and running it.
But it's certainly unnecessary now that the BDS isn't accessed at all
any more.
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
Reviewed-by: NMax Reitz <mreitz@redhat.com>
Reviewed-by: NJohn Snow <jsnow@redhat.com>

When block jobs need an AioContext, they just take it from their main
block node. Generic jobs don't have a main block node, so we need to
assign them an AioContext explicitly.
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
Reviewed-by: NMax Reitz <mreitz@redhat.com>
Reviewed-by: NJohn Snow <jsnow@redhat.com>

We cannot yet move the whole logic around job cancelling to Job because
it depends on quite a few other things that are still only in BlockJob,
but we can move the cancelled field at least.
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
Reviewed-by: NMax Reitz <mreitz@redhat.com>
Reviewed-by: NJohn Snow <jsnow@redhat.com>

This moves reference counting from BlockJob to Job.

In order to keep calling the BlockJob cleanup code when the job is
deleted via job_unref(), introduce a new JobDriver.free callback. Every
block job must use block_job_free() for this callback, this is asserted
in block_job_create().
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
Reviewed-by: NMax Reitz <mreitz@redhat.com>
Reviewed-by: NJohn Snow <jsnow@redhat.com>

This moves BlockJob.status and the closely related functions
(block_)job_state_transition() and (block_)job_apply_verb to Job. The
two QAPI enums are renamed to JobStatus and JobVerb.
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
Reviewed-by: NMax Reitz <mreitz@redhat.com>
Reviewed-by: NJohn Snow <jsnow@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>

This moves the job list from BlockJob to Job. Now we can check for
duplicate IDs in job_create().
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
Reviewed-by: NMax Reitz <mreitz@redhat.com>
Reviewed-by: NJohn Snow <jsnow@redhat.com>

This moves freeing the Job object and its fields from block_job_unref()
to job_delete().
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
Reviewed-by: NMax Reitz <mreitz@redhat.com>
Reviewed-by: NJohn Snow <jsnow@redhat.com>

This moves the job_type field from BlockJobDriver to JobDriver.
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
Reviewed-by: NMax Reitz <mreitz@redhat.com>
Reviewed-by: NJohn Snow <jsnow@redhat.com>

QAPI types aren't externally visible, so we can rename them without
causing problems. Before we add a job type to Job, rename the enum
so it can be used for more than just block jobs.
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Reviewed-by: NMax Reitz <mreitz@redhat.com>
Reviewed-by: NJohn Snow <jsnow@redhat.com>

This is the first step towards creating an infrastructure for generic
background jobs that aren't tied to a block device. For now, Job only
stores its ID and JobDriver, the rest stays in BlockJob.

The following patches will move over more parts of BlockJob to Job if
they are meaningful outside the context of a block job.

BlockJob.driver is now redundant, but this patch leaves it around to
avoid unnecessary churn. The next patches will get rid of almost all of
its uses anyway so that it can be removed later with much less churn.
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
Reviewed-by: NMax Reitz <mreitz@redhat.com>
Reviewed-by: NJohn Snow <jsnow@redhat.com>

Currently the timer is cancelled and the block job is entered by
block_job_resume().  This behavior causes drain to run extra blockjob
iterations when the job was sleeping due to the ratelimit.

This patch leaves the job asleep when block_job_resume() is called.
Jobs can still be forcibly woken up using block_job_enter(), which is
used to cancel jobs.

After this patch drain no longer runs extra blockjob iterations.  This
is the expected behavior that qemu-iotests 185 used to rely on.  We
temporarily changed the 185 test output to make it pass for the QEMU
2.12 release but now it's time to address this issue.

Cc: QingFeng Hao <haoqf@linux.vnet.ibm.com>
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Reviewed-by: NQingFeng Hao <haoqf@linux.vnet.ibm.com>
Message-id: 20180508135436.30140-3-stefanha@redhat.com
Reviewed-by: NJeff Cody <jcody@redhat.com>
Signed-off-by: NJeff Cody <jcody@redhat.com>

The backup block job directly accesses the driver field in BlockJob. Add
a wrapper for getting it.
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Reviewed-by: NMax Reitz <mreitz@redhat.com>
Reviewed-by: NJohn Snow <jsnow@redhat.com>

This gets us rid of more direct accesses to BlockJob fields from the
job drivers.
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Reviewed-by: NMax Reitz <mreitz@redhat.com>
Reviewed-by: NJohn Snow <jsnow@redhat.com>

All block job drivers support .set_speed and all of them duplicate the
same code to implement it. Move that code to blockjob.c and remove the
now useless callback.
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Reviewed-by: NMax Reitz <mreitz@redhat.com>
Reviewed-by: NJohn Snow <jsnow@redhat.com>

Block job drivers are not expected to mess with the internals of the
BlockJob object, so provide wrapper functions for one of the cases where
they still do it: Updating the progress counter.
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Reviewed-by: NMax Reitz <mreitz@redhat.com>
Reviewed-by: NJohn Snow <jsnow@redhat.com>

Every job gets a non-NULL job->txn on creation, but it doesn't
necessarily keep it until it is decommissioned: Finalising a job removes
it from its transaction. Therefore, calling 'blockdev-job-finalize' a
second time on an already concluded job causes an assertion failure.

Remove job->txn from the assertion in block_job_finalize() to fix this.
block_job_do_finalize() still has the same assertion, but if a job is
already removed from its transaction, block_job_apply_verb() will
already error out before we run into that assertion.

Cc: qemu-stable@nongnu.org
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Reviewed-by: NMax Reitz <mreitz@redhat.com>
Reviewed-by: NJohn Snow <jsnow@redhat.com>

When we've reached the concluded state, we need to expose the error
state if applicable. Add the new field.

This should be sufficient for determining if a job completed
successfully or not after concluding; if we want to discriminate
based on how it failed more mechanically, we can always add an
explicit return code enumeration later.

I didn't bother to make it only show up if we are in the concluded
state; I don't think it's necessary.

Cc: qemu-stable@nongnu.org
Signed-off-by: NJohn Snow <jsnow@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Reviewed-by: NAlberto Garcia <berto@igalia.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>