/*
* Declarations for long-running block device operations
*
* Copyright (c) 2011 IBM Corp.
* Copyright (c) 2012 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 BLOCKJOB_INT_H
#define BLOCKJOB_INT_H
#include "block/blockjob.h"
#include "block/block.h"
/**
* BlockJobDriver:
*
* A class type for block job driver.
*/
struct BlockJobDriver {
/** Derived BlockJob struct size */
size_t instance_size;
/** String describing the operation, part of query-block-jobs QMP API */
BlockJobType job_type;
/** Optional callback for job types that support setting a speed limit */
void (*set_speed)(BlockJob *job, int64_t speed, Error **errp);
/** Mandatory: Entrypoint for the Coroutine. */
CoroutineEntry *start;
/**
* Optional callback for job types whose completion must be triggered
* manually.
*/
void (*complete)(BlockJob *job, Error **errp);
/**
* If the callback is not NULL, it will be invoked when all the jobs
* belonging to the same transaction complete; or upon this job's
* completion if it is not in a transaction. Skipped if NULL.
*
* All jobs will complete with a call to either .commit() or .abort() but
* never both.
*/
void (*commit)(BlockJob *job);
/**
* If the callback is not NULL, it will be invoked when any job in the
* same transaction fails; or upon this job's failure (due to error or
* cancellation) if it is not in a transaction. Skipped if NULL.
*
* All jobs will complete with a call to either .commit() or .abort() but
* never both.
*/
void (*abort)(BlockJob *job);
/**
* If the callback is not NULL, it will be invoked after a call to either
* .commit() or .abort(). Regardless of which callback is invoked after
* completion, .clean() will always be called, even if the job does not
* belong to a transaction group.
*/
void (*clean)(BlockJob *job);
/**
* If the callback is not NULL, it will be invoked when the job transitions
* into the paused state. Paused jobs must not perform any asynchronous
* I/O or event loop activity. This callback is used to quiesce jobs.
*/
void coroutine_fn (*pause)(BlockJob *job);
/**
* If the callback is not NULL, it will be invoked when the job transitions
* out of the paused state. Any asynchronous I/O or event loop activity
* should be restarted from this callback.
*/
void coroutine_fn (*resume)(BlockJob *job);
/*
* If the callback is not NULL, it will be invoked before the job is
* resumed in a new AioContext. This is the place to move any resources
* besides job->blk to the new AioContext.
*/
void (*attached_aio_context)(BlockJob *job, AioContext *new_context);
/*
* If the callback is not NULL, it will be invoked when the job has to be
* synchronously cancelled or completed; it should drain BlockDriverStates
* as required to ensure progress.
*/
void (*drain)(BlockJob *job);
};
/**
* block_job_create:
* @job_id: The id of the newly-created job, or %NULL to have one
* generated automatically.
* @job_type: The class object for the newly-created job.
* @bs: The block
* @perm, @shared_perm: Permissions to request for @bs
* @speed: The maximum speed, in bytes per second, or 0 for unlimited.
* @cb: Completion function for the job.
* @opaque: Opaque pointer value passed to @cb.
* @errp: Error object.
*
* Create a new long-running block device job and return it. The job
* will call @cb asynchronously when the job completes. Note that
* @bs may have been closed at the time the @cb it is called. If
* this is the case, the job may be reported as either cancelled or
* completed.
*
* This function is not part of the public job interface; it should be
* called from a wrapper that is specific to the job type.
*/
void *block_job_create(const char *job_id, const BlockJobDriver *driver,
BlockDriverState *bs, uint64_t perm,
uint64_t shared_perm, int64_t speed, int flags,
BlockCompletionFunc *cb, void *opaque, Error **errp);
/**
* block_job_sleep_ns:
* @job: The job that calls the function.
* @clock: The clock to sleep on.
* @ns: How many nanoseconds to stop for.
*
* Put the job to sleep (assuming that it wasn't canceled) for @ns
* nanoseconds. Canceling the job will interrupt the wait immediately.
*/
void block_job_sleep_ns(BlockJob *job, QEMUClockType type, int64_t ns);
/**
* block_job_yield:
* @job: The job that calls the function.
*
* Yield the block job coroutine.
*/
void block_job_yield(BlockJob *job);
/**
* block_job_pause_all:
*
* Asynchronously pause all jobs.
*/
void block_job_pause_all(void);
/**
* block_job_resume_all:
*
* Resume all block jobs. Must be paired with a preceding block_job_pause_all.
*/
void block_job_resume_all(void);
/**
* block_job_early_fail:
* @bs: The block device.
*
* The block job could not be started, free it.
*/
void block_job_early_fail(BlockJob *job);
/**
* block_job_completed:
* @job: The job being completed.
* @ret: The status code.
*
* Call the completion function that was registered at creation time, and
* free @job.
*/
void block_job_completed(BlockJob *job, int ret);
/**
* block_job_is_cancelled:
* @job: The job being queried.
*
* Returns whether the job is scheduled for cancellation.
*/
bool block_job_is_cancelled(BlockJob *job);
/**
* block_job_pause_point:
* @job: The job that is ready to pause.
*
* Pause now if block_job_pause() has been called. Block jobs that perform
* lots of I/O must call this between requests so that the job can be paused.
*/
void coroutine_fn block_job_pause_point(BlockJob *job);
/**
* block_job_enter:
* @job: The job to enter.
*
* Continue the specified job by entering the coroutine.
*/
void block_job_enter(BlockJob *job);
/**
* block_job_event_ready:
* @job: The job which is now ready to be completed.
*
* Send a BLOCK_JOB_READY event for the specified job.
*/
void block_job_event_ready(BlockJob *job);
/**
* block_job_error_action:
* @job: The job to signal an error for.
* @on_err: The error action setting.
* @is_read: Whether the operation was a read.
* @error: The error that was reported.
*
* Report an I/O error for a block job and possibly stop the VM. Return the
* action that was selected based on @on_err and @error.
*/
BlockErrorAction block_job_error_action(BlockJob *job, BlockdevOnError on_err,
int is_read, int error);
typedef void BlockJobDeferToMainLoopFn(BlockJob *job, void *opaque);
/**
* block_job_defer_to_main_loop:
* @job: The job
* @fn: The function to run in the main loop
* @opaque: The opaque value that is passed to @fn
*
* This function must be called by the main job coroutine just before it
* returns. @fn is executed in the main loop with the BlockDriverState
* AioContext acquired. Block jobs must call bdrv_unref(), bdrv_close(), and
* anything that uses bdrv_drain_all() in the main loop.
*
* The @job AioContext is held while @fn executes.
*/
void block_job_defer_to_main_loop(BlockJob *job,
BlockJobDeferToMainLoopFn *fn,
void *opaque);
#endif
