job-monitor.h contains all functions of job.h that are used by the monitor and essentially all functions that do not define a JobDriver/Blockdriver.
No functional change intended. Signed-off-by: Emanuele Giuseppe Esposito <eespo...@redhat.com> --- include/qemu/job-monitor.h | 249 +++++++++++++++++++++++++++++++++++++ include/qemu/job.h | 204 +----------------------------- job.c | 1 + 3 files changed, 251 insertions(+), 203 deletions(-) create mode 100644 include/qemu/job-monitor.h diff --git a/include/qemu/job-monitor.h b/include/qemu/job-monitor.h new file mode 100644 index 0000000000..58e99a9a47 --- /dev/null +++ b/include/qemu/job-monitor.h @@ -0,0 +1,249 @@ +/* + * Declarations for background jobs + * + * Copyright (c) 2011 IBM Corp. + * Copyright (c) 2012, 2018 Red Hat, Inc. + * + * Permission is hereby granted, free of charge, to any person obtaining a copy + * of this software and associated documentation files (the "Software"), to deal + * in the Software without restriction, including without limitation the rights + * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell + * copies of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in + * all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, + * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN + * THE SOFTWARE. + */ + +#ifndef JOB_MONITOR_H +#define JOB_MONITOR_H + +#include "job-common.h" + +/* + * Job monitor API. + * + * These functions use are used by the QEMU monitor, for example + * to execute QMP commands. The monitor is aware of the job_mutex + * presence, so these functions assume it is held by the caller + * to protect job fields (see job-common.h). + * This prevents TOC/TOU bugs, allowing the caller to hold the + * lock between a check in the job state and the actual action. + * + * Therefore, each function in this API that needs protection + * must have the suffix "_locked" and the comment + * "Called between job_lock and job_unlock." + */ + + +/** + * Allocate and return a new job transaction. Jobs can be added to the + * transaction using job_txn_add_job_locked(). + * + * The transaction is automatically freed when the last job completes or is + * cancelled. + * + * All jobs in the transaction either complete successfully or fail/cancel as a + * group. Jobs wait for each other before completing. Cancelling one job + * cancels all jobs in the transaction. + */ +JobTxn *job_txn_new(void); + +/** + * Release a reference that was previously acquired with job_txn_add_job_locked + * or job_txn_new. If it's the last reference to the object, it will be freed. + * + * Called between job_lock and job_unlock. + */ +void job_txn_unref_locked(JobTxn *txn); + +/** + * Add a reference to Job refcnt, it will be decreased with job_unref_locked, + * and then be freed if it comes to be the last reference. + * + * Called between job_lock and job_unlock. + */ +void job_ref_locked(Job *job); + +/** + * Release a reference that was previously acquired with job_ref_locked() or + * job_create(). If it's the last reference to the object, it will be freed. + * + * Called between job_lock and job_unlock, but might release it temporarly. + */ +void job_unref_locked(Job *job); + +/** + * Conditionally enter the job coroutine if the job is ready to run, not + * already busy and fn() returns true. fn() is called while under the job_lock + * critical section. + * + * Called between job_lock and job_unlock, but might release it temporarly. + */ +void job_enter_cond_locked(Job *job, bool(*fn)(Job *job)); + +/** Just like job_is_cancelled, but called between job_lock and job_unlock */ +bool job_is_cancelled_locked(Job *job); + +/** Same as job_is_completed(), but assumes job_lock is held. */ +bool job_is_completed_locked(Job *job); + +/** Same as job_is_ready(), but assumes job_lock is held. */ +bool job_is_ready_locked(Job *job); + +/** + * Request @job to pause at the next pause point. Must be paired with + * job_resume_locked(). If the job is supposed to be resumed by user action, + * call job_user_pause_locked() instead. + * + * Called between job_lock and job_unlock. + */ +void job_pause_locked(Job *job); + +/** + * Resumes a @job paused with job_pause_locked. + * Called between job_lock and job_unlock. + */ +void job_resume_locked(Job *job); + +/** + * Asynchronously pause the specified @job. + * Do not allow a resume until a matching call to job_user_resume_locked. + * + * Called between job_lock and job_unlock. + */ +void job_user_pause_locked(Job *job, Error **errp); + +/** + * Returns true if the job is user-paused. + * Called between job_lock and job_unlock. + */ +bool job_user_paused_locked(Job *job); + +/** + * Resume the specified @job. + * Must be paired with a preceding job_user_pause_locked. + * + * Called between job_lock and job_unlock, but might release it temporarly. + */ +void job_user_resume_locked(Job *job, Error **errp); + +/** + * Get the next element from the list of block jobs after @job, or the + * first one if @job is %NULL. + * + * Returns the requested job, or %NULL if there are no more jobs left. + * + * Called between job_lock and job_unlock. + */ +Job *job_next_locked(Job *job); + +/** + * Get the job identified by @id (which must not be %NULL). + * + * Returns the requested job, or %NULL if it doesn't exist. + * + * Called between job_lock and job_unlock. + */ +Job *job_get_locked(const char *id); + +/** + * Check whether the verb @verb can be applied to @job in its current state. + * Returns 0 if the verb can be applied; otherwise errp is set and -EPERM + * returned. + * + * Called between job_lock and job_unlock. + */ +int job_apply_verb_locked(Job *job, JobVerb verb, Error **errp); + +/** + * Asynchronously complete the specified @job. + * Called between job_lock and job_unlock, but it releases the lock temporarly. + */ +void job_complete_locked(Job *job, Error **errp); + +/** + * Asynchronously cancel the specified @job. If @force is true, the job should + * be cancelled immediately without waiting for a consistent state. + * + * Called between job_lock and job_unlock. + */ +void job_cancel_locked(Job *job, bool force); + +/** + * Cancels the specified job like job_cancel_locked(), but may refuse to do so + * if the operation isn't meaningful in the current state of the job. + * + * Called between job_lock and job_unlock. + */ +void job_user_cancel_locked(Job *job, bool force, Error **errp); + +/** + * Synchronously cancel the @job. The completion callback is called + * before the function returns. If @force is false, the job may + * actually complete instead of canceling itself; the circumstances + * under which this happens depend on the kind of job that is active. + * + * Returns the return value from the job if the job actually completed + * during the call, or -ECANCELED if it was canceled. + * + * Called between job_lock and job_unlock. + */ +int job_cancel_sync_locked(Job *job, bool force); + +/** + * @job: The job to be completed. + * @errp: Error object which may be set by job_complete_locked(); this is not + * necessarily set on every error, the job return value has to be + * checked as well. + * + * Synchronously complete the job. The completion callback is called before the + * function returns, unless it is NULL (which is permissible when using this + * function). + * + * Returns the return value from the job. + * Called between job_lock and job_unlock. + */ +int job_complete_sync_locked(Job *job, Error **errp); + +/** + * For a @job that has finished its work and is pending awaiting explicit + * acknowledgement to commit its work, this will commit that work. + * + * FIXME: Make the below statement universally true: + * For jobs that support the manual workflow mode, all graph changes that occur + * as a result will occur after this command and before a successful reply. + * + * Called between job_lock and job_unlock. + */ +void job_finalize_locked(Job *job, Error **errp); + +/** + * Remove the concluded @job from the query list and resets the passed pointer + * to %NULL. Returns an error if the job is not actually concluded. + * + * Called between job_lock and job_unlock. + */ +void job_dismiss_locked(Job **job, Error **errp); + +/** + * Synchronously finishes the given @job. If @finish is given, it is called to + * trigger completion or cancellation of the job. + * + * Returns 0 if the job is successfully completed, -ECANCELED if the job was + * cancelled before completing, and -errno in other error cases. + * + * Called between job_lock and job_unlock. + */ +int job_finish_sync_locked(Job *job, void (*finish)(Job *, Error **errp), + Error **errp); + +#endif diff --git a/include/qemu/job.h b/include/qemu/job.h index cdfc603706..c2bbdef8e8 100644 --- a/include/qemu/job.h +++ b/include/qemu/job.h @@ -26,28 +26,7 @@ #ifndef JOB_H #define JOB_H -#include "job-common.h" - -/** - * Allocate and return a new job transaction. Jobs can be added to the - * transaction using job_txn_add_job_locked(). - * - * The transaction is automatically freed when the last job completes or is - * cancelled. - * - * All jobs in the transaction either complete successfully or fail/cancel as a - * group. Jobs wait for each other before completing. Cancelling one job - * cancels all jobs in the transaction. - */ -JobTxn *job_txn_new(void); - -/** - * Release a reference that was previously acquired with job_txn_add_job_locked - * or job_txn_new. If it's the last reference to the object, it will be freed. - * - * Called between job_lock and job_unlock. - */ -void job_txn_unref_locked(JobTxn *txn); +#include "job-monitor.h" /** * Create a new long-running job and return it. @@ -66,22 +45,6 @@ void *job_create(const char *job_id, const JobDriver *driver, JobTxn *txn, AioContext *ctx, int flags, BlockCompletionFunc *cb, void *opaque, Error **errp); -/** - * Add a reference to Job refcnt, it will be decreased with job_unref_locked, - * and then be freed if it comes to be the last reference. - * - * Called between job_lock and job_unlock. - */ -void job_ref_locked(Job *job); - -/** - * Release a reference that was previously acquired with job_ref_locked() or - * job_create(). If it's the last reference to the object, it will be freed. - * - * Called between job_lock and job_unlock, but might release it temporarly. - */ -void job_unref_locked(Job *job); - /** * @job: The job that has made progress * @done: How much progress the job made since the last call @@ -121,15 +84,6 @@ void job_progress_set_remaining(Job *job, uint64_t remaining); */ void job_progress_increase_remaining(Job *job, uint64_t delta); -/** - * Conditionally enter the job coroutine if the job is ready to run, not - * already busy and fn() returns true. fn() is called while under the job_lock - * critical section. - * - * Called between job_lock and job_unlock, but might release it temporarly. - */ -void job_enter_cond_locked(Job *job, bool(*fn)(Job *job)); - /** * @job: A job that has not yet been started. * @@ -188,9 +142,6 @@ void coroutine_fn job_sleep_ns(Job *job, int64_t ns); */ bool job_is_cancelled(Job *job); -/** Just like job_is_cancelled, but called between job_lock and job_unlock */ -bool job_is_cancelled_locked(Job *job); - /** * Returns whether the job is scheduled for cancellation (at an * indefinite point). @@ -204,83 +155,12 @@ bool job_cancel_requested(Job *job); */ bool job_is_completed(Job *job); -/** Same as job_is_completed(), but assumes job_lock is held. */ -bool job_is_completed_locked(Job *job); - /** * Returns whether the job is ready to be completed. * Called with job_mutex *not* held. */ bool job_is_ready(Job *job); -/** Same as job_is_ready(), but assumes job_lock is held. */ -bool job_is_ready_locked(Job *job); - -/** - * Request @job to pause at the next pause point. Must be paired with - * job_resume_locked(). If the job is supposed to be resumed by user action, - * call job_user_pause_locked() instead. - * - * Called between job_lock and job_unlock. - */ -void job_pause_locked(Job *job); - -/** - * Resumes a @job paused with job_pause_locked. - * Called between job_lock and job_unlock. - */ -void job_resume_locked(Job *job); - -/** - * Asynchronously pause the specified @job. - * Do not allow a resume until a matching call to job_user_resume_locked. - * - * Called between job_lock and job_unlock. - */ -void job_user_pause_locked(Job *job, Error **errp); - -/** - * Returns true if the job is user-paused. - * Called between job_lock and job_unlock. - */ -bool job_user_paused_locked(Job *job); - -/** - * Resume the specified @job. - * Must be paired with a preceding job_user_pause_locked. - * - * Called between job_lock and job_unlock, but might release it temporarly. - */ -void job_user_resume_locked(Job *job, Error **errp); - -/** - * Get the next element from the list of block jobs after @job, or the - * first one if @job is %NULL. - * - * Returns the requested job, or %NULL if there are no more jobs left. - * - * Called between job_lock and job_unlock. - */ -Job *job_next_locked(Job *job); - -/** - * Get the job identified by @id (which must not be %NULL). - * - * Returns the requested job, or %NULL if it doesn't exist. - * - * Called between job_lock and job_unlock. - */ -Job *job_get_locked(const char *id); - -/** - * Check whether the verb @verb can be applied to @job in its current state. - * Returns 0 if the verb can be applied; otherwise errp is set and -EPERM - * returned. - * - * Called between job_lock and job_unlock. - */ -int job_apply_verb_locked(Job *job, JobVerb verb, Error **errp); - /** * The @job could not be started, free it. * Called with job_mutex *not* held. @@ -293,41 +173,6 @@ void job_early_fail(Job *job); */ void job_transition_to_ready(Job *job); -/** - * Asynchronously complete the specified @job. - * Called between job_lock and job_unlock, but it releases the lock temporarly. - */ -void job_complete_locked(Job *job, Error **errp); - -/** - * Asynchronously cancel the specified @job. If @force is true, the job should - * be cancelled immediately without waiting for a consistent state. - * - * Called between job_lock and job_unlock. - */ -void job_cancel_locked(Job *job, bool force); - -/** - * Cancels the specified job like job_cancel_locked(), but may refuse to do so - * if the operation isn't meaningful in the current state of the job. - * - * Called between job_lock and job_unlock. - */ -void job_user_cancel_locked(Job *job, bool force, Error **errp); - -/** - * Synchronously cancel the @job. The completion callback is called - * before the function returns. If @force is false, the job may - * actually complete instead of canceling itself; the circumstances - * under which this happens depend on the kind of job that is active. - * - * Returns the return value from the job if the job actually completed - * during the call, or -ECANCELED if it was canceled. - * - * Called between job_lock and job_unlock. - */ -int job_cancel_sync_locked(Job *job, bool force); - /** * Synchronously force-cancels all jobs using job_cancel_sync_locked(). * @@ -337,53 +182,6 @@ int job_cancel_sync_locked(Job *job, bool force); */ void job_cancel_sync_all(void); -/** - * @job: The job to be completed. - * @errp: Error object which may be set by job_complete_locked(); this is not - * necessarily set on every error, the job return value has to be - * checked as well. - * - * Synchronously complete the job. The completion callback is called before the - * function returns, unless it is NULL (which is permissible when using this - * function). - * - * Returns the return value from the job. - * Called between job_lock and job_unlock. - */ -int job_complete_sync_locked(Job *job, Error **errp); - -/** - * For a @job that has finished its work and is pending awaiting explicit - * acknowledgement to commit its work, this will commit that work. - * - * FIXME: Make the below statement universally true: - * For jobs that support the manual workflow mode, all graph changes that occur - * as a result will occur after this command and before a successful reply. - * - * Called between job_lock and job_unlock. - */ -void job_finalize_locked(Job *job, Error **errp); - -/** - * Remove the concluded @job from the query list and resets the passed pointer - * to %NULL. Returns an error if the job is not actually concluded. - * - * Called between job_lock and job_unlock. - */ -void job_dismiss_locked(Job **job, Error **errp); - -/** - * Synchronously finishes the given @job. If @finish is given, it is called to - * trigger completion or cancellation of the job. - * - * Returns 0 if the job is successfully completed, -ECANCELED if the job was - * cancelled before completing, and -errno in other error cases. - * - * Called between job_lock and job_unlock. - */ -int job_finish_sync_locked(Job *job, void (*finish)(Job *, Error **errp), - Error **errp); - /** * Sets the @job->aio_context. * Called with job_mutex *not* held. diff --git a/job.c b/job.c index c7a41d88d6..844102befb 100644 --- a/job.c +++ b/job.c @@ -40,6 +40,7 @@ * therefore needs consistency across job_get and the actual operation * (e.g. job_user_cancel). To achieve this consistency, the caller * calls job_lock/job_unlock itself around the whole operation. + * These functions are declared in job-monitor.h. * * * The second includes functions used by the block job drivers and sometimes -- 2.31.1