257 lines
8.5 KiB
C
257 lines
8.5 KiB
C
/*
|
|
* 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 {
|
|
/** Generic JobDriver callbacks and settings */
|
|
JobDriver job_driver;
|
|
|
|
/** 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, prepare 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.
|
|
*
|
|
* This callback will not be invoked if the job has already failed.
|
|
* If it fails, abort and then clean will be called.
|
|
*/
|
|
int (*prepare)(BlockJob *job);
|
|
|
|
/**
|
|
* 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.
|
|
* @driver: The class object for the newly-created job.
|
|
* @txn: The transaction this job belongs to, if any. %NULL otherwise.
|
|
* @bs: The block
|
|
* @perm, @shared_perm: Permissions to request for @bs
|
|
* @speed: The maximum speed, in bytes per second, or 0 for unlimited.
|
|
* @flags: Creation flags for the Block Job.
|
|
* See @BlockJobCreateFlags
|
|
* @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,
|
|
BlockJobTxn *txn, 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.
|
|
* @ns: How many nanoseconds to stop for.
|
|
*
|
|
* Put the job to sleep (assuming that it wasn't canceled) for @ns
|
|
* %QEMU_CLOCK_REALTIME nanoseconds. Canceling the job will immediately
|
|
* interrupt the wait.
|
|
*/
|
|
void block_job_sleep_ns(BlockJob *job, 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_ratelimit_get_delay:
|
|
*
|
|
* Calculate and return delay for the next request in ns. See the documentation
|
|
* of ratelimit_calculate_delay() for details.
|
|
*/
|
|
int64_t block_job_ratelimit_get_delay(BlockJob *job, uint64_t n);
|
|
|
|
/**
|
|
* 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
|