summaryrefslogtreecommitdiff
path: root/block/mirror.c
AgeCommit message (Collapse)AuthorFilesLines
2018-09-25block/mirror: conservative mirror_exit refactorJohn Snow1-11/+33
For purposes of minimum code movement, refactor the mirror_exit callback to use the post-finalization callbacks in a trivial way. Signed-off-by: John Snow <jsnow@redhat.com> Message-id: 20180906130225.5118-7-jsnow@redhat.com Reviewed-by: Jeff Cody <jcody@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> [mreitz: Added comment for the mirror_exit() function] Signed-off-by: Max Reitz <mreitz@redhat.com>
2018-09-25block/mirror: don't install backing chain on abortJohn Snow1-1/+1
In cases where we abort the block/mirror job, there's no point in installing the new backing chain before we finish aborting. Signed-off-by: John Snow <jsnow@redhat.com> Message-id: 20180906130225.5118-6-jsnow@redhat.com Reviewed-by: Jeff Cody <jcody@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Signed-off-by: Max Reitz <mreitz@redhat.com>
2018-09-25block/mirror: add block job creation flagsJohn Snow1-2/+3
Add support for taking and passing forward job creation flags. Signed-off-by: John Snow <jsnow@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Jeff Cody <jcody@redhat.com> Message-id: 20180906130225.5118-3-jsnow@redhat.com Signed-off-by: Max Reitz <mreitz@redhat.com>
2018-08-31block/mirror: utilize job_exit shimJohn Snow1-18/+11
Change the manual deferment to mirror_exit into the implicit callback to job_exit and the mirror_exit callback. This does change the order of some bdrv_unref calls and job_completed, but thanks to the new context in which we call .exit, this is safe to defer the possible flushing of any nodes to the job_finalize_single cleanup stage. Signed-off-by: John Snow <jsnow@redhat.com> Message-id: 20180830015734.19765-6-jsnow@redhat.com Reviewed-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Jeff Cody <jcody@redhat.com> Signed-off-by: Max Reitz <mreitz@redhat.com>
2018-08-31jobs: canonize Error objectJohn Snow1-1/+1
Jobs presently use both an Error object in the case of the create job, and char strings in the case of generic errors elsewhere. Unify the two paths as just j->err, and remove the extra argument from job_completed. The integer error code for job_completed is kept for now, to be removed shortly in a separate patch. Signed-off-by: John Snow <jsnow@redhat.com> Message-id: 20180830015734.19765-3-jsnow@redhat.com [mreitz: Dropped a superfluous g_strdup()] Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Max Reitz <mreitz@redhat.com>
2018-08-31jobs: change start callback to run callbackJohn Snow1-4/+6
Presently we codify the entry point for a job as the "start" callback, but a more apt name would be "run" to clarify the idea that when this function returns we consider the job to have "finished," except for any cleanup which occurs in separate callbacks later. As part of this clarification, change the signature to include an error object and a return code. The error ptr is not yet used, and the return code while captured, will be overwritten by actions in the job_completed function. Signed-off-by: John Snow <jsnow@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Message-id: 20180830015734.19765-2-jsnow@redhat.com Reviewed-by: Jeff Cody <jcody@redhat.com> Signed-off-by: Max Reitz <mreitz@redhat.com>
2018-08-15block: drop empty .bdrv_close handlersVladimir Sementsov-Ogievskiy1-5/+0
.bdrv_close handler is optional after previous commit, no needs to keep empty functions more. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2018-08-15mirror: Fail gracefully for source == targetKevin Wolf1-0/+5
blockdev-mirror with the same node for source and target segfaults today: A node is in its own backing chain, so mirror_start_job() decides that this is an active commit. When adding the intermediate nodes with block_job_add_bdrv(), it starts the iteration through the subchain with the backing file of source, though, so it never reaches target and instead runs into NULL at the base. While we could fix that by starting with source itself, there is no point in allowing mirroring a node into itself and I wouldn't be surprised if this caused more problems later. So just check for this scenario and error out. Cc: qemu-stable@nongnu.org Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com>
2018-07-10block: Use BdrvChild to discardFam Zheng1-1/+1
Other I/O functions are already using a BdrvChild pointer in the API, so make discard do the same. It makes it possible to initiate the same permission checks before doing I/O, and much easier to share the helper functions for this, which will be added and used by write, truncate and copy range paths. Signed-off-by: Fam Zheng <famz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2018-06-18block/mirror: Add copy mode QAPI interfaceMax Reitz1-5/+7
This patch allows the user to specify whether to use active or only background mode for mirror block jobs. Currently, this setting will remain constant for the duration of the entire block job. Signed-off-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Alberto Garcia <berto@igalia.com> Message-id: 20180613181823.13618-14-mreitz@redhat.com Signed-off-by: Max Reitz <mreitz@redhat.com>
2018-06-18block/mirror: Add active mirroringMax Reitz1-5/+247
This patch implements active synchronous mirroring. In active mode, the passive mechanism will still be in place and is used to copy all initially dirty clusters off the source disk; but every write request will write data both to the source and the target disk, so the source cannot be dirtied faster than data is mirrored to the target. Also, once the block job has converged (BLOCK_JOB_READY sent), source and target are guaranteed to stay in sync (unless an error occurs). Active mode is completely optional and currently disabled at runtime. A later patch will add a way for users to enable it. Signed-off-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com> Message-id: 20180613181823.13618-13-mreitz@redhat.com Signed-off-by: Max Reitz <mreitz@redhat.com>
2018-06-18block/mirror: Add MirrorBDSOpaqueMax Reitz1-0/+12
This will allow us to access the block job data when the mirror block driver becomes more complex. Signed-off-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com> Message-id: 20180613181823.13618-11-mreitz@redhat.com Signed-off-by: Max Reitz <mreitz@redhat.com>
2018-06-18block/mirror: Use source as a BdrvChildMax Reitz1-8/+6
With this, the mirror_top_bs is no longer just a technically required node in the BDS graph but actually represents the block job operation. Also, drop MirrorBlockJob.source, as we can reach it through mirror_top_bs->backing. Signed-off-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com> Reviewed-by: Alberto Garcia <berto@igalia.com> Message-id: 20180613181823.13618-6-mreitz@redhat.com Signed-off-by: Max Reitz <mreitz@redhat.com>
2018-06-18block/mirror: Wait for in-flight op conflictsMax Reitz1-18/+84
This patch makes the mirror code differentiate between simply waiting for any operation to complete (mirror_wait_for_free_in_flight_slot()) and specifically waiting for all operations touching a certain range of the virtual disk to complete (mirror_wait_on_conflicts()). Signed-off-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com> Message-id: 20180613181823.13618-5-mreitz@redhat.com Signed-off-by: Max Reitz <mreitz@redhat.com>
2018-06-18block/mirror: Use CoQueue to wait on in-flight opsMax Reitz1-11/+23
Attach a CoQueue to each in-flight operation so if we need to wait for any we can use it to wait instead of just blindly yielding and hoping for some operation to wake us. A later patch will use this infrastructure to allow requests accessing the same area of the virtual disk to specifically wait for each other. Signed-off-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com> Message-id: 20180613181823.13618-4-mreitz@redhat.com Signed-off-by: Max Reitz <mreitz@redhat.com>
2018-06-18block/mirror: Convert to coroutinesMax Reitz1-62/+90
In order to talk to the source BDS (and maybe in the future to the target BDS as well) directly, we need to convert our existing AIO requests into coroutine I/O requests. Signed-off-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com> Message-id: 20180613181823.13618-3-mreitz@redhat.com Signed-off-by: Max Reitz <mreitz@redhat.com>
2018-06-18block/mirror: Pull out mirror_perform()Max Reitz1-22/+29
When converting mirror's I/O to coroutines, we are going to need a point where these coroutines are created. mirror_perform() is going to be that point. Signed-off-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Reviewed-by: Jeff Cody <jcody@redhat.com> Reviewed-by: Alberto Garcia <berto@igalia.com> Message-id: 20180613181823.13618-2-mreitz@redhat.com Signed-off-by: Max Reitz <mreitz@redhat.com>
2018-06-18block: Really pause block jobs on drainKevin Wolf1-0/+8
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>
2018-05-30job: Add error message for failing jobsKevin Wolf1-1/+1
So far we relied on job->ret and strerror() to produce an error message for failed jobs. Not surprisingly, this tends to result in completely useless messages. This adds a Job.error field that can contain an error string for a failing job, and a parameter to job_completed() that sets the field. As a default, if NULL is passed, we continue to use strerror(job->ret). All existing callers are changed to pass NULL. They can be improved in separate patches. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Jeff Cody <jcody@redhat.com>
2018-05-23job: Move progress fields to JobKevin Wolf1-2/+2
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 Wolf1-3/+3
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_yield()Kevin Wolf1-1/+1
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 Wolf1-3/+3
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 .complete callback to JobKevin Wolf1-5/+5
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 Wolf1-0/+2
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 Wolf1-2/+2
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 Wolf1-1/+1
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: Move BlockJobCreateFlags to JobKevin Wolf1-1/+1
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: Move pause/resume functions to JobKevin Wolf1-0/+2
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 Wolf1-2/+2
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 Wolf1-11/+11
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 Wolf1-7/+8
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: Move cancelled to JobKevin Wolf1-10/+10
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 Wolf1-0/+2
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: Add JobDriver.job_typeKevin Wolf1-2/+2
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 Wolf1-2/+2
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 Wolf1-3/+7
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>
2018-05-15block: Support BDRV_REQ_WRITE_UNCHANGED in filtersMax Reitz1-0/+2
Update the rest of the filter drivers to support BDRV_REQ_WRITE_UNCHANGED. They already forward write request flags to their children, so we just have to announce support for it. This patch does not cover the replication driver because that currently does not support flags at all, and because it just grabs the WRITE permission for its children when it can, so we should be fine just submitting the incoming WRITE_UNCHANGED requests as normal writes. It also does not cover format drivers for similar reasons. They all use bdrv_format_default_perms() as their .bdrv_child_perm() implementation so they just always grab the WRITE permission for their file children whenever possible. In addition, it often would be difficult to ascertain whether incoming unchanging writes end up as unchanging writes in their files. So we just leave them as normal potentially changing writes. Signed-off-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Alberto Garcia <berto@igalia.com> Message-id: 20180421132929.21610-7-mreitz@redhat.com Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Max Reitz <mreitz@redhat.com>
2018-05-15blockjob: Introduce block_job_ratelimit_get_delay()Kevin Wolf1-4/+1
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 Wolf1-20/+6
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: Move RateLimit to BlockJobKevin Wolf1-3/+3
Every block job has a RateLimit, and they all do the exact same thing with it, so it should be common infrastructure. Move the struct field for a start. 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 Wolf1-6/+5
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>
2018-05-08block/mirror: Make cancel always cancel pre-READYMax Reitz1-1/+3
Commit b76e4458b1eb3c32e9824fe6aa51f67d2b251748 made the mirror block job respect block-job-cancel's @force flag: With that flag set, it would now always really cancel, even post-READY. Unfortunately, it had a side effect: Without that flag set, it would now never cancel, not even before READY. Considering that is an incompatible change and not noted anywhere in the commit or the description of block-job-cancel's @force parameter, this seems unintentional and we should revert to the previous behavior, which is to immediately cancel the job when block-job-cancel is called before source and target are in sync (i.e. before the READY event). Cc: qemu-stable@nongnu.org Buglink: https://bugzilla.redhat.com/show_bug.cgi?id=1572856 Reported-by: Yanan Fu <yfu@redhat.com> Signed-off-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Message-id: 20180501220509.14152-2-mreitz@redhat.com Reviewed-by: Jeff Cody <jcody@redhat.com> Signed-off-by: Jeff Cody <jcody@redhat.com>
2018-05-08block/mirror: honor ratelimit againStefan Hajnoczi1-3/+5
Commit b76e4458b1eb3c32e9824fe6aa51f67d2b251748 ("block/mirror: change the semantic of 'force' of block-job-cancel") accidentally removed the ratelimit in the mirror job. Reintroduce the ratelimit but keep the block-job-cancel force=true behavior that was added in commit b76e4458b1eb3c32e9824fe6aa51f67d2b251748. Note that block_job_sleep_ns() returns immediately when the job is cancelled. Therefore it's safe to unconditionally call block_job_sleep_ns() - a cancelled job does not sleep. This commit fixes the non-deterministic qemu-iotests 185 output. The test relies on the ratelimit to make the job sleep until the 'quit' command is processed. Previously the job could complete before the 'quit' command was received since there was no ratelimit. Cc: Liang Li <liliang.opensource@gmail.com> Cc: Jeff Cody <jcody@redhat.com> Cc: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Message-id: 20180424123527.19168-1-stefanha@redhat.com Signed-off-by: Jeff Cody <jcody@redhat.com>
2018-03-19block/mirror: change the semantic of 'force' of block-job-cancelLiang Li1-6/+4
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: model single jobs as transactionsJohn Snow1-1/+1
model all independent jobs as single job transactions. It's one less case we have to worry about when we add more states to the transition machine. This way, we can just treat all job lifetimes exactly the same. This helps tighten assertions of the STM graph and removes some conditionals that would have been needed in the coming commits adding a more explicit job lifetime management API. Signed-off-by: John Snow <jsnow@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2018-03-02block: Switch passthrough drivers to .bdrv_co_block_status()Eric Blake1-1/+1
We are gradually moving away from sector-based interfaces, towards byte-based. Update the generic helpers, and all passthrough clients (blkdebug, commit, mirror, throttle) accordingly. Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Reviewed-by: Fam Zheng <famz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2017-11-29blockjob: remove clock argument from block_job_sleep_nsPaolo Bonzini1-3/+3
All callers are using QEMU_CLOCK_REALTIME, and it will not be possible to support more than one clock when block_job_sleep_ns switches to a single timer stored in the BlockJob struct. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alberto Garcia <berto@igalia.com> Tested-By: Jeff Cody <jcody@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com> Reviewed-by: Jeff Cody <jcody@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2017-10-26block: Convert bdrv_get_block_status_above() to bytesEric Blake1-12/+6
We are gradually moving away from sector-based interfaces, towards byte-based. In the common case, allocation is unlikely to ever use values that are not naturally sector-aligned, but it is possible that byte-based values will let us be more precise about allocation at the end of an unaligned file that can do byte-based access. Changing the name of the function from bdrv_get_block_status_above() to bdrv_block_status_above() ensures that the compiler enforces that all callers are updated. Likewise, since it a byte interface allows an offset mapping that might not be sector aligned, split the mapping out of the return value and into a pass-by-reference parameter. For now, the io.c layer still assert()s that all uses are sector-aligned, but that can be relaxed when a later patch implements byte-based block status in the drivers. For the most part this patch is just the addition of scaling at the callers followed by inverse scaling at bdrv_block_status(), plus updates for the new split return interface. But some code, particularly bdrv_block_status(), gets a lot simpler because it no longer has to mess with sectors. Likewise, mirror code no longer computes s->granularity >> BDRV_SECTOR_BITS, and can therefore drop an assertion about alignment because the loop no longer depends on alignment (never mind that we don't really have a driver that reports sub-sector alignments, so it's not really possible to test the effect of sub-sector mirroring). Fix a neighboring assertion to use is_power_of_2 while there. For ease of review, bdrv_get_block_status() was tackled separately. Signed-off-by: Eric Blake <eblake@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2017-10-26block: Make bdrv_round_to_clusters() signature more usefulEric Blake1-4/+3
In the process of converting sector-based interfaces to bytes, I'm finding it easier to represent a byte count as a 64-bit integer at the block layer (even if we are internally capped by SIZE_MAX or even INT_MAX for individual transactions, it's still nicer to not have to worry about truncation/overflow issues on as many variables). Update the signature of bdrv_round_to_clusters() to uniformly use int64_t, matching the signature already chosen for bdrv_is_allocated and the fact that off_t is also a signed type, then adjust clients according to the required fallout (even where the result could now exceed 32 bits, no client is directly assigning the result into a 32-bit value without breaking things into a loop first). Signed-off-by: Eric Blake <eblake@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>