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2018-09-25block: Use a single global AioWaitKevin Wolf
When draining a block node, we recurse to its parent and for subtree drains also to its children. A single AIO_WAIT_WHILE() is then used to wait for bdrv_drain_poll() to become true, which depends on all of the nodes we recursed to. However, if the respective child or parent becomes quiescent and calls bdrv_wakeup(), only the AioWait of the child/parent is checked, while AIO_WAIT_WHILE() depends on the AioWait of the original node. Fix this by using a single AioWait for all callers of AIO_WAIT_WHILE(). This may mean that the draining thread gets a few more unnecessary wakeups because an unrelated operation got completed, but we already wake it up when something _could_ have changed rather than only if it has certainly changed. Apart from that, drain is a slow path anyway. In theory it would be possible to use wakeups more selectively and still correctly, but the gains are likely not worth the additional complexity. In fact, this patch is a nice simplification for some places in the code. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com>
2018-09-25blockjob: Lie better in child_job_drained_poll()Kevin Wolf
Block jobs claim in .drained_poll() that they are in a quiescent state as soon as job->deferred_to_main_loop is true. This is obviously wrong, they still have a completion BH to run. We only get away with this because commit 91af091f923 added an unconditional aio_poll(false) to the drain functions, but this is bypassing the regular drain mechanisms. However, just removing this and telling that the job is still active doesn't work either: The completion callbacks themselves call drain functions (directly, or indirectly with bdrv_reopen), so they would deadlock then. As a better lie, tell that the job is active as long as the BH is pending, but falsely call it quiescent from the point in the BH when the completion callback is called. At this point, nested drain calls won't deadlock because they ignore the job, and outer drains will wait for the job to really reach a quiescent state because the callback is already running. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com>
2018-09-25blockjob: Wake up BDS when job becomes idleKevin Wolf
In the context of draining a BDS, the .drained_poll callback of block jobs is called. If this returns true (i.e. there is still some activity pending), the drain operation may call aio_poll() with blocking=true to wait for completion. As soon as the pending activity is completed and the job finally arrives in a quiescent state (i.e. its coroutine either yields with busy=false or terminates), the block job must notify the aio_poll() loop to wake up, otherwise we get a deadlock if both are running in different threads. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com>
2018-08-28qapi: Drop qapi_event_send_FOO()'s Error ** argumentPeter Xu
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: Eric Blake <eblake@redhat.com> Suggested-by: Markus Armbruster <armbru@redhat.com> Signed-off-by: Peter Xu <peterx@redhat.com> Message-Id: <20180815133747.25032-4-peterx@redhat.com> Reviewed-by: Markus Armbruster <armbru@redhat.com> [Commit message rewritten, update to qapi-code-gen.txt corrected] Signed-off-by: Markus Armbruster <armbru@redhat.com>
2018-06-18block: Really pause block jobs on drainKevin Wolf
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: Kevin Wolf <kwolf@redhat.com>
2018-05-23blockjob: Remove BlockJob.driverKevin Wolf
BlockJob.driver is redundant with Job.driver and only used in very few places any more. Remove it. Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2018-05-23job: Move progress fields to JobKevin Wolf
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: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com>
2018-05-23job: Add job_transition_to_ready()Kevin Wolf
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: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com>
2018-05-23job: Add job_is_ready()Kevin Wolf
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 ef6dbf1e46e, 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: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com>
2018-05-23job: Add job_dismiss()Kevin Wolf
This moves block_job_dismiss() to the Job layer. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com>
2018-05-23job: Add job_yield()Kevin Wolf
This moves block_job_yield() to the Job layer. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com>
2018-05-23job: Move completion and cancellation to JobKevin Wolf
This moves the top-level job completion and cancellation functions from BlockJob to Job. Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2018-05-23job: Move transactions to JobKevin Wolf
This moves the logic that implements job transactions from BlockJob to Job. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com>
2018-05-23job: Switch transactions to JobTxnKevin Wolf
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: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com>
2018-05-23job: Move job_finish_sync() to JobKevin Wolf
block_job_finish_sync() doesn't contain anything block job specific any more, so it can be moved to Job. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com>
2018-05-23job: Move .complete callback to JobKevin Wolf
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: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com>
2018-05-23job: Add job_drain()Kevin Wolf
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: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com>
2018-05-23job: Convert block_job_cancel_async() to JobKevin Wolf
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: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com>
2018-05-23job: Move single job finalisation to JobKevin Wolf
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: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com>
2018-05-23job: Add job_event_*()Kevin Wolf
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: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com>
2018-05-23blockjob: Split block_job_event_pending()Kevin Wolf
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: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com>
2018-05-23job: Move BlockJobCreateFlags to JobKevin Wolf
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: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com>
2018-05-23job: Replace BlockJob.completed with job_is_completed()Kevin Wolf
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: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Reviewed-by: John Snow <jsnow@redhat.com>
2018-05-23job: Move pause/resume functions to JobKevin Wolf
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: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Reviewed-by: John Snow <jsnow@redhat.com>
2018-05-23job: Add job_sleep_ns()Kevin Wolf
There is nothing block layer specific about block_job_sleep_ns(), so move the function to Job. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: John Snow <jsnow@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com>
2018-05-23job: Move coroutine and related code to JobKevin Wolf
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: Kevin Wolf <kwolf@redhat.com> Reviewed-by: John Snow <jsnow@redhat.com>
2018-05-23job: Move defer_to_main_loop to JobKevin Wolf
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: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Reviewed-by: John Snow <jsnow@redhat.com>
2018-05-23job: Add Job.aio_contextKevin Wolf
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: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Reviewed-by: John Snow <jsnow@redhat.com>
2018-05-23job: Move cancelled to JobKevin Wolf
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: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Reviewed-by: John Snow <jsnow@redhat.com>
2018-05-23job: Add reference countingKevin Wolf
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: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Reviewed-by: John Snow <jsnow@redhat.com>
2018-05-23job: Move state transitions to JobKevin Wolf
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: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Reviewed-by: John Snow <jsnow@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com>
2018-05-23job: Maintain a list of all jobsKevin Wolf
This moves the job list from BlockJob to Job. Now we can check for duplicate IDs in job_create(). Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Reviewed-by: John Snow <jsnow@redhat.com>
2018-05-23job: Add job_delete()Kevin Wolf
This moves freeing the Job object and its fields from block_job_unref() to job_delete(). Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Reviewed-by: John Snow <jsnow@redhat.com>
2018-05-23job: Add JobDriver.job_typeKevin Wolf
This moves the job_type field from BlockJobDriver to JobDriver. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Reviewed-by: John Snow <jsnow@redhat.com>
2018-05-23job: Rename BlockJobType into JobTypeKevin Wolf
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: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Reviewed-by: John Snow <jsnow@redhat.com>
2018-05-23job: Create Job, JobDriver and job_create()Kevin Wolf
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: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Reviewed-by: John Snow <jsnow@redhat.com>
2018-05-16blockjob: do not cancel timer in resumeStefan Hajnoczi
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: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: QingFeng Hao <haoqf@linux.vnet.ibm.com> Message-id: 20180508135436.30140-3-stefanha@redhat.com Reviewed-by: Jeff Cody <jcody@redhat.com> Signed-off-by: Jeff Cody <jcody@redhat.com>
2018-05-15blockjob: Add block_job_driver()Kevin Wolf
The backup block job directly accesses the driver field in BlockJob. Add a wrapper for getting it. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Reviewed-by: John Snow <jsnow@redhat.com>
2018-05-15blockjob: Introduce block_job_ratelimit_get_delay()Kevin Wolf
This gets us rid of more direct accesses to BlockJob fields from the job drivers. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Reviewed-by: John Snow <jsnow@redhat.com>
2018-05-15blockjob: Implement block_job_set_speed() centrallyKevin Wolf
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: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Reviewed-by: John Snow <jsnow@redhat.com>
2018-05-15blockjob: Wrappers for progress counter accessKevin Wolf
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: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Reviewed-by: John Snow <jsnow@redhat.com>
2018-05-15blockjob: Fix assertion in block_job_finalize()Kevin Wolf
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: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Reviewed-by: John Snow <jsnow@redhat.com>
2018-05-15blockjob: expose error string via queryJohn Snow
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: John Snow <jsnow@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Alberto Garcia <berto@igalia.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2018-05-10blockjob: drop block_job_pause/resume_all()Stefan Hajnoczi
Commit 8119334918e86f45877cfc139192d54f2449a239 ("block: Don't block_job_pause_all() in bdrv_drain_all()") removed the only callers of block_job_pause/resume_all(). Pausing and resuming now happens in child_job_drained_begin/end() so it's no longer necessary to globally pause/resume jobs. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: John Snow <jsnow@redhat.com> Reviewed-by: Alberto Garcia <berto@igalia.com> Message-id: 20180424085240.5798-1-stefanha@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2018-04-03blockjob: use qapi enum helpersMarc-André Lureau
QAPI generator provide #define helpers for looking up enum string. Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com> Reviewed-by: John Snow <jsnow@redhat.com> Message-id: 20180327153011.29569-1-marcandre.lureau@redhat.com Signed-off-by: Jeff Cody <jcody@redhat.com>
2018-04-03blockjob: leak fix, remove from txn when failing earlyMarc-André Lureau
This fixes leaks found by ASAN such as: GTESTER tests/test-blockjob ================================================================= ==31442==ERROR: LeakSanitizer: detected memory leaks Direct leak of 24 byte(s) in 1 object(s) allocated from: #0 0x7f88483cba38 in __interceptor_calloc (/lib64/libasan.so.4+0xdea38) #1 0x7f8845e1bd77 in g_malloc0 ../glib/gmem.c:129 #2 0x7f8845e1c04b in g_malloc0_n ../glib/gmem.c:360 #3 0x5584d2732498 in block_job_txn_new /home/elmarco/src/qemu/blockjob.c:172 #4 0x5584d2739b28 in block_job_create /home/elmarco/src/qemu/blockjob.c:973 #5 0x5584d270ae31 in mk_job /home/elmarco/src/qemu/tests/test-blockjob.c:34 #6 0x5584d270b1c1 in do_test_id /home/elmarco/src/qemu/tests/test-blockjob.c:57 #7 0x5584d270b65c in test_job_ids /home/elmarco/src/qemu/tests/test-blockjob.c:118 #8 0x7f8845e40b69 in test_case_run ../glib/gtestutils.c:2255 #9 0x7f8845e40f29 in g_test_run_suite_internal ../glib/gtestutils.c:2339 #10 0x7f8845e40fd2 in g_test_run_suite_internal ../glib/gtestutils.c:2351 #11 0x7f8845e411e9 in g_test_run_suite ../glib/gtestutils.c:2426 #12 0x7f8845e3fe72 in g_test_run ../glib/gtestutils.c:1692 #13 0x5584d270d6e2 in main /home/elmarco/src/qemu/tests/test-blockjob.c:377 #14 0x7f8843641f29 in __libc_start_main (/lib64/libc.so.6+0x20f29) Add an assert to make sure that the job doesn't have associated txn before free(). [Jeff Cody: N.B., used updated patch provided by John Snow] Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com> Signed-off-by: Jeff Cody <jcody@redhat.com>
2018-03-19block/mirror: change the semantic of 'force' of block-job-cancelLiang Li
When doing drive mirror to a low speed shared storage, if there was heavy BLK IO write workload in VM after the 'ready' event, drive mirror block job can't be canceled immediately, it would keep running until the heavy BLK IO workload stopped in the VM. Libvirt depends on the current block-job-cancel semantics, which is that when used without a flag after the 'ready' event, the command blocks until data is in sync. However, these semantics are awkward in other situations, for example, people may use drive mirror for realtime backups while still wanting to use block live migration. Libvirt cannot start a block live migration while another drive mirror is in progress, but the user would rather abandon the backup attempt as broken and proceed with the live migration than be stuck waiting for the current drive mirror backup to finish. The drive-mirror command already includes a 'force' flag, which libvirt does not use, although it documented the flag as only being useful to quit a job which is paused. However, since quitting a paused job has the same effect as abandoning a backup in a non-paused job (namely, the destination file is not in sync, and the command completes immediately), we can just improve the documentation to make the force flag obviously useful. Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Jeff Cody <jcody@redhat.com> Cc: Kevin Wolf <kwolf@redhat.com> Cc: Max Reitz <mreitz@redhat.com> Cc: Eric Blake <eblake@redhat.com> Cc: John Snow <jsnow@redhat.com> Reported-by: Huaitong Han <huanhuaitong@didichuxing.com> Signed-off-by: Huaitong Han <huanhuaitong@didichuxing.com> Signed-off-by: Liang Li <liliangleo@didichuxing.com> Signed-off-by: Jeff Cody <jcody@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2018-03-19blockjobs: Expose manual propertyJohn Snow
Expose the "manual" property via QAPI for the backup-related jobs. As of this commit, this allows the management API to request the "concluded" and "dismiss" semantics for backup jobs. Signed-off-by: John Snow <jsnow@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2018-03-19blockjobs: add block-job-finalizeJohn Snow
Instead of automatically transitioning from PENDING to CONCLUDED, gate the .prepare() and .commit() phases behind an explicit acknowledgement provided by the QMP monitor if auto_finalize = false has been requested. This allows us to perform graph changes in prepare and/or commit so that graph changes do not occur autonomously without knowledge of the controlling management layer. Transactions that have reached the "PENDING" state together can all be moved to invoke their finalization methods by issuing block_job_finalize to any one job in the transaction. Jobs in a transaction with mixed job->auto_finalize settings will all remain stuck in the "PENDING" state, as if the entire transaction was specified with auto_finalize = false. Jobs that specified auto_finalize = true, however, will still not emit the PENDING event. Signed-off-by: John Snow <jsnow@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2018-03-19blockjobs: add PENDING status and eventJohn Snow
For jobs utilizing the new manual workflow, we intend to prohibit them from modifying the block graph until the management layer provides an explicit ACK via block-job-finalize to move the process forward. To distinguish this runstate from "ready" or "waiting," we add a new "pending" event and status. For now, the transition from PENDING to CONCLUDED/ABORTING is automatic, but a future commit will add the explicit block-job-finalize step. Transitions: Waiting -> Pending: Normal transition. Pending -> Concluded: Normal transition. Pending -> Aborting: Late transactional failures and cancellations. Removed Transitions: Waiting -> Concluded: Jobs must go to PENDING first. Verbs: Cancel: Can be applied to a pending job. +---------+ |UNDEFINED| +--+------+ | +--v----+ +---------+CREATED+-----------------+ | +--+----+ | | | | | +--+----+ +------+ | +---------+RUNNING<----->PAUSED| | | +--+-+--+ +------+ | | | | | | | +------------------+ | | | | | | +--v--+ +-------+ | | +---------+READY<------->STANDBY| | | | +--+--+ +-------+ | | | | | | | +--v----+ | | +---------+WAITING<---------------+ | | +--+----+ | | | | | +--v----+ | +---------+PENDING| | | +--+----+ | | | | +--v-----+ +--v------+ | |ABORTING+--->CONCLUDED| | +--------+ +--+------+ | | | +--v-+ | |NULL<--------------------+ +----+ Signed-off-by: John Snow <jsnow@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>