hw/misc/led: Add yellow LED
[qemu/ar7.git] / job.c
blob289edee143740c4598069d595125b67cc38d204e
1 /*
2 * Background jobs (long-running operations)
4 * Copyright (c) 2011 IBM Corp.
5 * Copyright (c) 2012, 2018 Red Hat, Inc.
7 * Permission is hereby granted, free of charge, to any person obtaining a copy
8 * of this software and associated documentation files (the "Software"), to deal
9 * in the Software without restriction, including without limitation the rights
10 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
11 * copies of the Software, and to permit persons to whom the Software is
12 * furnished to do so, subject to the following conditions:
14 * The above copyright notice and this permission notice shall be included in
15 * all copies or substantial portions of the Software.
17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
18 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
19 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
20 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
21 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
22 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
23 * THE SOFTWARE.
26 #include "qemu/osdep.h"
27 #include "qapi/error.h"
28 #include "qemu/job.h"
29 #include "qemu/id.h"
30 #include "qemu/main-loop.h"
31 #include "block/aio-wait.h"
32 #include "trace/trace-root.h"
33 #include "qapi/qapi-events-job.h"
35 static QLIST_HEAD(, Job) jobs = QLIST_HEAD_INITIALIZER(jobs);
37 /* Job State Transition Table */
38 bool JobSTT[JOB_STATUS__MAX][JOB_STATUS__MAX] = {
39 /* U, C, R, P, Y, S, W, D, X, E, N */
40 /* U: */ [JOB_STATUS_UNDEFINED] = {0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0},
41 /* C: */ [JOB_STATUS_CREATED] = {0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 1},
42 /* R: */ [JOB_STATUS_RUNNING] = {0, 0, 0, 1, 1, 0, 1, 0, 1, 0, 0},
43 /* P: */ [JOB_STATUS_PAUSED] = {0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0},
44 /* Y: */ [JOB_STATUS_READY] = {0, 0, 0, 0, 0, 1, 1, 0, 1, 0, 0},
45 /* S: */ [JOB_STATUS_STANDBY] = {0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0},
46 /* W: */ [JOB_STATUS_WAITING] = {0, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0},
47 /* D: */ [JOB_STATUS_PENDING] = {0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 0},
48 /* X: */ [JOB_STATUS_ABORTING] = {0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 0},
49 /* E: */ [JOB_STATUS_CONCLUDED] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1},
50 /* N: */ [JOB_STATUS_NULL] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0},
53 bool JobVerbTable[JOB_VERB__MAX][JOB_STATUS__MAX] = {
54 /* U, C, R, P, Y, S, W, D, X, E, N */
55 [JOB_VERB_CANCEL] = {0, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0},
56 [JOB_VERB_PAUSE] = {0, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0},
57 [JOB_VERB_RESUME] = {0, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0},
58 [JOB_VERB_SET_SPEED] = {0, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0},
59 [JOB_VERB_COMPLETE] = {0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0},
60 [JOB_VERB_FINALIZE] = {0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0},
61 [JOB_VERB_DISMISS] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0},
64 /* Transactional group of jobs */
65 struct JobTxn {
67 /* Is this txn being cancelled? */
68 bool aborting;
70 /* List of jobs */
71 QLIST_HEAD(, Job) jobs;
73 /* Reference count */
74 int refcnt;
77 /* Right now, this mutex is only needed to synchronize accesses to job->busy
78 * and job->sleep_timer, such as concurrent calls to job_do_yield and
79 * job_enter. */
80 static QemuMutex job_mutex;
82 static void job_lock(void)
84 qemu_mutex_lock(&job_mutex);
87 static void job_unlock(void)
89 qemu_mutex_unlock(&job_mutex);
92 static void __attribute__((__constructor__)) job_init(void)
94 qemu_mutex_init(&job_mutex);
97 JobTxn *job_txn_new(void)
99 JobTxn *txn = g_new0(JobTxn, 1);
100 QLIST_INIT(&txn->jobs);
101 txn->refcnt = 1;
102 return txn;
105 static void job_txn_ref(JobTxn *txn)
107 txn->refcnt++;
110 void job_txn_unref(JobTxn *txn)
112 if (txn && --txn->refcnt == 0) {
113 g_free(txn);
117 void job_txn_add_job(JobTxn *txn, Job *job)
119 if (!txn) {
120 return;
123 assert(!job->txn);
124 job->txn = txn;
126 QLIST_INSERT_HEAD(&txn->jobs, job, txn_list);
127 job_txn_ref(txn);
130 static void job_txn_del_job(Job *job)
132 if (job->txn) {
133 QLIST_REMOVE(job, txn_list);
134 job_txn_unref(job->txn);
135 job->txn = NULL;
139 static int job_txn_apply(Job *job, int fn(Job *))
141 AioContext *inner_ctx;
142 Job *other_job, *next;
143 JobTxn *txn = job->txn;
144 int rc = 0;
147 * Similar to job_completed_txn_abort, we take each job's lock before
148 * applying fn, but since we assume that outer_ctx is held by the caller,
149 * we need to release it here to avoid holding the lock twice - which would
150 * break AIO_WAIT_WHILE from within fn.
152 job_ref(job);
153 aio_context_release(job->aio_context);
155 QLIST_FOREACH_SAFE(other_job, &txn->jobs, txn_list, next) {
156 inner_ctx = other_job->aio_context;
157 aio_context_acquire(inner_ctx);
158 rc = fn(other_job);
159 aio_context_release(inner_ctx);
160 if (rc) {
161 break;
166 * Note that job->aio_context might have been changed by calling fn, so we
167 * can't use a local variable to cache it.
169 aio_context_acquire(job->aio_context);
170 job_unref(job);
171 return rc;
174 bool job_is_internal(Job *job)
176 return (job->id == NULL);
179 static void job_state_transition(Job *job, JobStatus s1)
181 JobStatus s0 = job->status;
182 assert(s1 >= 0 && s1 < JOB_STATUS__MAX);
183 trace_job_state_transition(job, job->ret,
184 JobSTT[s0][s1] ? "allowed" : "disallowed",
185 JobStatus_str(s0), JobStatus_str(s1));
186 assert(JobSTT[s0][s1]);
187 job->status = s1;
189 if (!job_is_internal(job) && s1 != s0) {
190 qapi_event_send_job_status_change(job->id, job->status);
194 int job_apply_verb(Job *job, JobVerb verb, Error **errp)
196 JobStatus s0 = job->status;
197 assert(verb >= 0 && verb < JOB_VERB__MAX);
198 trace_job_apply_verb(job, JobStatus_str(s0), JobVerb_str(verb),
199 JobVerbTable[verb][s0] ? "allowed" : "prohibited");
200 if (JobVerbTable[verb][s0]) {
201 return 0;
203 error_setg(errp, "Job '%s' in state '%s' cannot accept command verb '%s'",
204 job->id, JobStatus_str(s0), JobVerb_str(verb));
205 return -EPERM;
208 JobType job_type(const Job *job)
210 return job->driver->job_type;
213 const char *job_type_str(const Job *job)
215 return JobType_str(job_type(job));
218 bool job_is_cancelled(Job *job)
220 return job->cancelled;
223 bool job_is_ready(Job *job)
225 switch (job->status) {
226 case JOB_STATUS_UNDEFINED:
227 case JOB_STATUS_CREATED:
228 case JOB_STATUS_RUNNING:
229 case JOB_STATUS_PAUSED:
230 case JOB_STATUS_WAITING:
231 case JOB_STATUS_PENDING:
232 case JOB_STATUS_ABORTING:
233 case JOB_STATUS_CONCLUDED:
234 case JOB_STATUS_NULL:
235 return false;
236 case JOB_STATUS_READY:
237 case JOB_STATUS_STANDBY:
238 return true;
239 default:
240 g_assert_not_reached();
242 return false;
245 bool job_is_completed(Job *job)
247 switch (job->status) {
248 case JOB_STATUS_UNDEFINED:
249 case JOB_STATUS_CREATED:
250 case JOB_STATUS_RUNNING:
251 case JOB_STATUS_PAUSED:
252 case JOB_STATUS_READY:
253 case JOB_STATUS_STANDBY:
254 return false;
255 case JOB_STATUS_WAITING:
256 case JOB_STATUS_PENDING:
257 case JOB_STATUS_ABORTING:
258 case JOB_STATUS_CONCLUDED:
259 case JOB_STATUS_NULL:
260 return true;
261 default:
262 g_assert_not_reached();
264 return false;
267 static bool job_started(Job *job)
269 return job->co;
272 static bool job_should_pause(Job *job)
274 return job->pause_count > 0;
277 Job *job_next(Job *job)
279 if (!job) {
280 return QLIST_FIRST(&jobs);
282 return QLIST_NEXT(job, job_list);
285 Job *job_get(const char *id)
287 Job *job;
289 QLIST_FOREACH(job, &jobs, job_list) {
290 if (job->id && !strcmp(id, job->id)) {
291 return job;
295 return NULL;
298 static void job_sleep_timer_cb(void *opaque)
300 Job *job = opaque;
302 job_enter(job);
305 void *job_create(const char *job_id, const JobDriver *driver, JobTxn *txn,
306 AioContext *ctx, int flags, BlockCompletionFunc *cb,
307 void *opaque, Error **errp)
309 Job *job;
311 if (job_id) {
312 if (flags & JOB_INTERNAL) {
313 error_setg(errp, "Cannot specify job ID for internal job");
314 return NULL;
316 if (!id_wellformed(job_id)) {
317 error_setg(errp, "Invalid job ID '%s'", job_id);
318 return NULL;
320 if (job_get(job_id)) {
321 error_setg(errp, "Job ID '%s' already in use", job_id);
322 return NULL;
324 } else if (!(flags & JOB_INTERNAL)) {
325 error_setg(errp, "An explicit job ID is required");
326 return NULL;
329 job = g_malloc0(driver->instance_size);
330 job->driver = driver;
331 job->id = g_strdup(job_id);
332 job->refcnt = 1;
333 job->aio_context = ctx;
334 job->busy = false;
335 job->paused = true;
336 job->pause_count = 1;
337 job->auto_finalize = !(flags & JOB_MANUAL_FINALIZE);
338 job->auto_dismiss = !(flags & JOB_MANUAL_DISMISS);
339 job->cb = cb;
340 job->opaque = opaque;
342 notifier_list_init(&job->on_finalize_cancelled);
343 notifier_list_init(&job->on_finalize_completed);
344 notifier_list_init(&job->on_pending);
345 notifier_list_init(&job->on_ready);
347 job_state_transition(job, JOB_STATUS_CREATED);
348 aio_timer_init(qemu_get_aio_context(), &job->sleep_timer,
349 QEMU_CLOCK_REALTIME, SCALE_NS,
350 job_sleep_timer_cb, job);
352 QLIST_INSERT_HEAD(&jobs, job, job_list);
354 /* Single jobs are modeled as single-job transactions for sake of
355 * consolidating the job management logic */
356 if (!txn) {
357 txn = job_txn_new();
358 job_txn_add_job(txn, job);
359 job_txn_unref(txn);
360 } else {
361 job_txn_add_job(txn, job);
364 return job;
367 void job_ref(Job *job)
369 ++job->refcnt;
372 void job_unref(Job *job)
374 if (--job->refcnt == 0) {
375 assert(job->status == JOB_STATUS_NULL);
376 assert(!timer_pending(&job->sleep_timer));
377 assert(!job->txn);
379 if (job->driver->free) {
380 job->driver->free(job);
383 QLIST_REMOVE(job, job_list);
385 error_free(job->err);
386 g_free(job->id);
387 g_free(job);
391 void job_progress_update(Job *job, uint64_t done)
393 progress_work_done(&job->progress, done);
396 void job_progress_set_remaining(Job *job, uint64_t remaining)
398 progress_set_remaining(&job->progress, remaining);
401 void job_progress_increase_remaining(Job *job, uint64_t delta)
403 progress_increase_remaining(&job->progress, delta);
406 void job_event_cancelled(Job *job)
408 notifier_list_notify(&job->on_finalize_cancelled, job);
411 void job_event_completed(Job *job)
413 notifier_list_notify(&job->on_finalize_completed, job);
416 static void job_event_pending(Job *job)
418 notifier_list_notify(&job->on_pending, job);
421 static void job_event_ready(Job *job)
423 notifier_list_notify(&job->on_ready, job);
426 static void job_event_idle(Job *job)
428 notifier_list_notify(&job->on_idle, job);
431 void job_enter_cond(Job *job, bool(*fn)(Job *job))
433 if (!job_started(job)) {
434 return;
436 if (job->deferred_to_main_loop) {
437 return;
440 job_lock();
441 if (job->busy) {
442 job_unlock();
443 return;
446 if (fn && !fn(job)) {
447 job_unlock();
448 return;
451 assert(!job->deferred_to_main_loop);
452 timer_del(&job->sleep_timer);
453 job->busy = true;
454 job_unlock();
455 aio_co_enter(job->aio_context, job->co);
458 void job_enter(Job *job)
460 job_enter_cond(job, NULL);
463 /* Yield, and schedule a timer to reenter the coroutine after @ns nanoseconds.
464 * Reentering the job coroutine with job_enter() before the timer has expired
465 * is allowed and cancels the timer.
467 * If @ns is (uint64_t) -1, no timer is scheduled and job_enter() must be
468 * called explicitly. */
469 static void coroutine_fn job_do_yield(Job *job, uint64_t ns)
471 job_lock();
472 if (ns != -1) {
473 timer_mod(&job->sleep_timer, ns);
475 job->busy = false;
476 job_event_idle(job);
477 job_unlock();
478 qemu_coroutine_yield();
480 /* Set by job_enter_cond() before re-entering the coroutine. */
481 assert(job->busy);
484 void coroutine_fn job_pause_point(Job *job)
486 assert(job && job_started(job));
488 if (!job_should_pause(job)) {
489 return;
491 if (job_is_cancelled(job)) {
492 return;
495 if (job->driver->pause) {
496 job->driver->pause(job);
499 if (job_should_pause(job) && !job_is_cancelled(job)) {
500 JobStatus status = job->status;
501 job_state_transition(job, status == JOB_STATUS_READY
502 ? JOB_STATUS_STANDBY
503 : JOB_STATUS_PAUSED);
504 job->paused = true;
505 job_do_yield(job, -1);
506 job->paused = false;
507 job_state_transition(job, status);
510 if (job->driver->resume) {
511 job->driver->resume(job);
515 void job_yield(Job *job)
517 assert(job->busy);
519 /* Check cancellation *before* setting busy = false, too! */
520 if (job_is_cancelled(job)) {
521 return;
524 if (!job_should_pause(job)) {
525 job_do_yield(job, -1);
528 job_pause_point(job);
531 void coroutine_fn job_sleep_ns(Job *job, int64_t ns)
533 assert(job->busy);
535 /* Check cancellation *before* setting busy = false, too! */
536 if (job_is_cancelled(job)) {
537 return;
540 if (!job_should_pause(job)) {
541 job_do_yield(job, qemu_clock_get_ns(QEMU_CLOCK_REALTIME) + ns);
544 job_pause_point(job);
547 /* Assumes the block_job_mutex is held */
548 static bool job_timer_not_pending(Job *job)
550 return !timer_pending(&job->sleep_timer);
553 void job_pause(Job *job)
555 job->pause_count++;
556 if (!job->paused) {
557 job_enter(job);
561 void job_resume(Job *job)
563 assert(job->pause_count > 0);
564 job->pause_count--;
565 if (job->pause_count) {
566 return;
569 /* kick only if no timer is pending */
570 job_enter_cond(job, job_timer_not_pending);
573 void job_user_pause(Job *job, Error **errp)
575 if (job_apply_verb(job, JOB_VERB_PAUSE, errp)) {
576 return;
578 if (job->user_paused) {
579 error_setg(errp, "Job is already paused");
580 return;
582 job->user_paused = true;
583 job_pause(job);
586 bool job_user_paused(Job *job)
588 return job->user_paused;
591 void job_user_resume(Job *job, Error **errp)
593 assert(job);
594 if (!job->user_paused || job->pause_count <= 0) {
595 error_setg(errp, "Can't resume a job that was not paused");
596 return;
598 if (job_apply_verb(job, JOB_VERB_RESUME, errp)) {
599 return;
601 if (job->driver->user_resume) {
602 job->driver->user_resume(job);
604 job->user_paused = false;
605 job_resume(job);
608 static void job_do_dismiss(Job *job)
610 assert(job);
611 job->busy = false;
612 job->paused = false;
613 job->deferred_to_main_loop = true;
615 job_txn_del_job(job);
617 job_state_transition(job, JOB_STATUS_NULL);
618 job_unref(job);
621 void job_dismiss(Job **jobptr, Error **errp)
623 Job *job = *jobptr;
624 /* similarly to _complete, this is QMP-interface only. */
625 assert(job->id);
626 if (job_apply_verb(job, JOB_VERB_DISMISS, errp)) {
627 return;
630 job_do_dismiss(job);
631 *jobptr = NULL;
634 void job_early_fail(Job *job)
636 assert(job->status == JOB_STATUS_CREATED);
637 job_do_dismiss(job);
640 static void job_conclude(Job *job)
642 job_state_transition(job, JOB_STATUS_CONCLUDED);
643 if (job->auto_dismiss || !job_started(job)) {
644 job_do_dismiss(job);
648 static void job_update_rc(Job *job)
650 if (!job->ret && job_is_cancelled(job)) {
651 job->ret = -ECANCELED;
653 if (job->ret) {
654 if (!job->err) {
655 error_setg(&job->err, "%s", strerror(-job->ret));
657 job_state_transition(job, JOB_STATUS_ABORTING);
661 static void job_commit(Job *job)
663 assert(!job->ret);
664 if (job->driver->commit) {
665 job->driver->commit(job);
669 static void job_abort(Job *job)
671 assert(job->ret);
672 if (job->driver->abort) {
673 job->driver->abort(job);
677 static void job_clean(Job *job)
679 if (job->driver->clean) {
680 job->driver->clean(job);
684 static int job_finalize_single(Job *job)
686 assert(job_is_completed(job));
688 /* Ensure abort is called for late-transactional failures */
689 job_update_rc(job);
691 if (!job->ret) {
692 job_commit(job);
693 } else {
694 job_abort(job);
696 job_clean(job);
698 if (job->cb) {
699 job->cb(job->opaque, job->ret);
702 /* Emit events only if we actually started */
703 if (job_started(job)) {
704 if (job_is_cancelled(job)) {
705 job_event_cancelled(job);
706 } else {
707 job_event_completed(job);
711 job_txn_del_job(job);
712 job_conclude(job);
713 return 0;
716 static void job_cancel_async(Job *job, bool force)
718 if (job->driver->cancel) {
719 job->driver->cancel(job);
721 if (job->user_paused) {
722 /* Do not call job_enter here, the caller will handle it. */
723 if (job->driver->user_resume) {
724 job->driver->user_resume(job);
726 job->user_paused = false;
727 assert(job->pause_count > 0);
728 job->pause_count--;
730 job->cancelled = true;
731 /* To prevent 'force == false' overriding a previous 'force == true' */
732 job->force_cancel |= force;
735 static void job_completed_txn_abort(Job *job)
737 AioContext *outer_ctx = job->aio_context;
738 AioContext *ctx;
739 JobTxn *txn = job->txn;
740 Job *other_job;
742 if (txn->aborting) {
744 * We are cancelled by another job, which will handle everything.
746 return;
748 txn->aborting = true;
749 job_txn_ref(txn);
751 /* We can only hold the single job's AioContext lock while calling
752 * job_finalize_single() because the finalization callbacks can involve
753 * calls of AIO_WAIT_WHILE(), which could deadlock otherwise. */
754 aio_context_release(outer_ctx);
756 /* Other jobs are effectively cancelled by us, set the status for
757 * them; this job, however, may or may not be cancelled, depending
758 * on the caller, so leave it. */
759 QLIST_FOREACH(other_job, &txn->jobs, txn_list) {
760 if (other_job != job) {
761 ctx = other_job->aio_context;
762 aio_context_acquire(ctx);
763 job_cancel_async(other_job, false);
764 aio_context_release(ctx);
767 while (!QLIST_EMPTY(&txn->jobs)) {
768 other_job = QLIST_FIRST(&txn->jobs);
769 ctx = other_job->aio_context;
770 aio_context_acquire(ctx);
771 if (!job_is_completed(other_job)) {
772 assert(job_is_cancelled(other_job));
773 job_finish_sync(other_job, NULL, NULL);
775 job_finalize_single(other_job);
776 aio_context_release(ctx);
779 aio_context_acquire(outer_ctx);
781 job_txn_unref(txn);
784 static int job_prepare(Job *job)
786 if (job->ret == 0 && job->driver->prepare) {
787 job->ret = job->driver->prepare(job);
788 job_update_rc(job);
790 return job->ret;
793 static int job_needs_finalize(Job *job)
795 return !job->auto_finalize;
798 static void job_do_finalize(Job *job)
800 int rc;
801 assert(job && job->txn);
803 /* prepare the transaction to complete */
804 rc = job_txn_apply(job, job_prepare);
805 if (rc) {
806 job_completed_txn_abort(job);
807 } else {
808 job_txn_apply(job, job_finalize_single);
812 void job_finalize(Job *job, Error **errp)
814 assert(job && job->id);
815 if (job_apply_verb(job, JOB_VERB_FINALIZE, errp)) {
816 return;
818 job_do_finalize(job);
821 static int job_transition_to_pending(Job *job)
823 job_state_transition(job, JOB_STATUS_PENDING);
824 if (!job->auto_finalize) {
825 job_event_pending(job);
827 return 0;
830 void job_transition_to_ready(Job *job)
832 job_state_transition(job, JOB_STATUS_READY);
833 job_event_ready(job);
836 static void job_completed_txn_success(Job *job)
838 JobTxn *txn = job->txn;
839 Job *other_job;
841 job_state_transition(job, JOB_STATUS_WAITING);
844 * Successful completion, see if there are other running jobs in this
845 * txn.
847 QLIST_FOREACH(other_job, &txn->jobs, txn_list) {
848 if (!job_is_completed(other_job)) {
849 return;
851 assert(other_job->ret == 0);
854 job_txn_apply(job, job_transition_to_pending);
856 /* If no jobs need manual finalization, automatically do so */
857 if (job_txn_apply(job, job_needs_finalize) == 0) {
858 job_do_finalize(job);
862 static void job_completed(Job *job)
864 assert(job && job->txn && !job_is_completed(job));
866 job_update_rc(job);
867 trace_job_completed(job, job->ret);
868 if (job->ret) {
869 job_completed_txn_abort(job);
870 } else {
871 job_completed_txn_success(job);
875 /** Useful only as a type shim for aio_bh_schedule_oneshot. */
876 static void job_exit(void *opaque)
878 Job *job = (Job *)opaque;
879 AioContext *ctx;
881 job_ref(job);
882 aio_context_acquire(job->aio_context);
884 /* This is a lie, we're not quiescent, but still doing the completion
885 * callbacks. However, completion callbacks tend to involve operations that
886 * drain block nodes, and if .drained_poll still returned true, we would
887 * deadlock. */
888 job->busy = false;
889 job_event_idle(job);
891 job_completed(job);
894 * Note that calling job_completed can move the job to a different
895 * aio_context, so we cannot cache from above. job_txn_apply takes care of
896 * acquiring the new lock, and we ref/unref to avoid job_completed freeing
897 * the job underneath us.
899 ctx = job->aio_context;
900 job_unref(job);
901 aio_context_release(ctx);
905 * All jobs must allow a pause point before entering their job proper. This
906 * ensures that jobs can be paused prior to being started, then resumed later.
908 static void coroutine_fn job_co_entry(void *opaque)
910 Job *job = opaque;
912 assert(job && job->driver && job->driver->run);
913 job_pause_point(job);
914 job->ret = job->driver->run(job, &job->err);
915 job->deferred_to_main_loop = true;
916 job->busy = true;
917 aio_bh_schedule_oneshot(qemu_get_aio_context(), job_exit, job);
920 void job_start(Job *job)
922 assert(job && !job_started(job) && job->paused &&
923 job->driver && job->driver->run);
924 job->co = qemu_coroutine_create(job_co_entry, job);
925 job->pause_count--;
926 job->busy = true;
927 job->paused = false;
928 job_state_transition(job, JOB_STATUS_RUNNING);
929 aio_co_enter(job->aio_context, job->co);
932 void job_cancel(Job *job, bool force)
934 if (job->status == JOB_STATUS_CONCLUDED) {
935 job_do_dismiss(job);
936 return;
938 job_cancel_async(job, force);
939 if (!job_started(job)) {
940 job_completed(job);
941 } else if (job->deferred_to_main_loop) {
942 job_completed_txn_abort(job);
943 } else {
944 job_enter(job);
948 void job_user_cancel(Job *job, bool force, Error **errp)
950 if (job_apply_verb(job, JOB_VERB_CANCEL, errp)) {
951 return;
953 job_cancel(job, force);
956 /* A wrapper around job_cancel() taking an Error ** parameter so it may be
957 * used with job_finish_sync() without the need for (rather nasty) function
958 * pointer casts there. */
959 static void job_cancel_err(Job *job, Error **errp)
961 job_cancel(job, false);
964 int job_cancel_sync(Job *job)
966 return job_finish_sync(job, &job_cancel_err, NULL);
969 void job_cancel_sync_all(void)
971 Job *job;
972 AioContext *aio_context;
974 while ((job = job_next(NULL))) {
975 aio_context = job->aio_context;
976 aio_context_acquire(aio_context);
977 job_cancel_sync(job);
978 aio_context_release(aio_context);
982 int job_complete_sync(Job *job, Error **errp)
984 return job_finish_sync(job, job_complete, errp);
987 void job_complete(Job *job, Error **errp)
989 /* Should not be reachable via external interface for internal jobs */
990 assert(job->id);
991 if (job_apply_verb(job, JOB_VERB_COMPLETE, errp)) {
992 return;
994 if (job->pause_count || job_is_cancelled(job) || !job->driver->complete) {
995 error_setg(errp, "The active block job '%s' cannot be completed",
996 job->id);
997 return;
1000 job->driver->complete(job, errp);
1003 int job_finish_sync(Job *job, void (*finish)(Job *, Error **errp), Error **errp)
1005 Error *local_err = NULL;
1006 int ret;
1008 job_ref(job);
1010 if (finish) {
1011 finish(job, &local_err);
1013 if (local_err) {
1014 error_propagate(errp, local_err);
1015 job_unref(job);
1016 return -EBUSY;
1019 AIO_WAIT_WHILE(job->aio_context,
1020 (job_enter(job), !job_is_completed(job)));
1022 ret = (job_is_cancelled(job) && job->ret == 0) ? -ECANCELED : job->ret;
1023 job_unref(job);
1024 return ret;