2 * Declarations for long-running block device operations
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29 #include "block/block.h"
31 typedef struct BlockJobDriver BlockJobDriver
;
32 typedef struct BlockJobTxn BlockJobTxn
;
37 * Long-running operation on a BlockDriverState.
39 typedef struct BlockJob
{
40 /** The job type, including the job vtable. */
41 const BlockJobDriver
*driver
;
43 /** The block device on which the job is operating. */
47 * The ID of the block job. May be NULL for internal jobs.
52 * The coroutine that executes the job. If not NULL, it is
53 * reentered when busy is false and the job is cancelled.
58 * Set to true if the job should cancel itself. The flag must
59 * always be tested just before toggling the busy flag from false
60 * to true. After a job has been cancelled, it should only yield
61 * if #aio_poll will ("sooner or later") reenter the coroutine.
66 * Counter for pause request. If non-zero, the block job is either paused,
67 * or if busy == true will pause itself as soon as possible.
72 * Set to true if the job is paused by user. Can be unpaused with the
73 * block-job-resume QMP command.
78 * Set to false by the job while the coroutine has yielded and may be
79 * re-entered by block_job_enter(). There may still be I/O or event loop
80 * activity pending. Accessed under block_job_mutex (in blockjob.c).
85 * Set to true by the job while it is in a quiescent state, where
86 * no I/O or event loop activity is pending.
91 * Set to true when the job is ready to be completed.
96 * Set to true when the job has deferred work to the main loop.
98 bool deferred_to_main_loop
;
100 /** Element of the list of block jobs */
101 QLIST_ENTRY(BlockJob
) job_list
;
103 /** Status that is published by the query-block-jobs QMP API */
104 BlockDeviceIoStatus iostatus
;
106 /** Offset that is published by the query-block-jobs QMP API */
109 /** Length that is published by the query-block-jobs QMP API */
112 /** Speed that was set with @block_job_set_speed. */
115 /** The completion function that will be called when the job completes. */
116 BlockCompletionFunc
*cb
;
118 /** Block other operations when block job is running */
121 /** BlockDriverStates that are involved in this block job */
124 /** The opaque value that is passed to the completion function. */
127 /** Reference count of the block job */
130 /** True when job has reported completion by calling block_job_completed. */
133 /** ret code passed to block_job_completed. */
137 * Timer that is used by @block_job_sleep_ns. Accessed under
138 * block_job_mutex (in blockjob.c).
140 QEMUTimer sleep_timer
;
142 /** Current state; See @BlockJobStatus for details. */
143 BlockJobStatus status
;
146 QLIST_ENTRY(BlockJob
) txn_list
;
149 typedef enum BlockJobCreateFlags
{
150 /* Default behavior */
151 BLOCK_JOB_DEFAULT
= 0x00,
152 /* BlockJob is not QMP-created and should not send QMP events */
153 BLOCK_JOB_INTERNAL
= 0x01,
154 } BlockJobCreateFlags
;
158 * @job: A block job, or %NULL.
160 * Get the next element from the list of block jobs after @job, or the
161 * first one if @job is %NULL.
163 * Returns the requested job, or %NULL if there are no more jobs left.
165 BlockJob
*block_job_next(BlockJob
*job
);
169 * @id: The id of the block job.
171 * Get the block job identified by @id (which must not be %NULL).
173 * Returns the requested job, or %NULL if it doesn't exist.
175 BlockJob
*block_job_get(const char *id
);
178 * block_job_add_bdrv:
180 * @name: The name to assign to the new BdrvChild
181 * @bs: A BlockDriverState that is involved in @job
182 * @perm, @shared_perm: Permissions to request on the node
184 * Add @bs to the list of BlockDriverState that are involved in
185 * @job. This means that all operations will be blocked on @bs while
188 int block_job_add_bdrv(BlockJob
*job
, const char *name
, BlockDriverState
*bs
,
189 uint64_t perm
, uint64_t shared_perm
, Error
**errp
);
192 * block_job_remove_all_bdrv:
193 * @job: The block job
195 * Remove all BlockDriverStates from the list of nodes that are involved in the
196 * job. This removes the blockers added with block_job_add_bdrv().
198 void block_job_remove_all_bdrv(BlockJob
*job
);
201 * block_job_set_speed:
202 * @job: The job to set the speed for.
203 * @speed: The new value
204 * @errp: Error object.
206 * Set a rate-limiting parameter for the job; the actual meaning may
207 * vary depending on the job type.
209 void block_job_set_speed(BlockJob
*job
, int64_t speed
, Error
**errp
);
213 * @job: A job that has not yet been started.
215 * Begins execution of a block job.
216 * Takes ownership of one reference to the job object.
218 void block_job_start(BlockJob
*job
);
222 * @job: The job to be canceled.
224 * Asynchronously cancel the specified job.
226 void block_job_cancel(BlockJob
*job
);
229 * block_job_complete:
230 * @job: The job to be completed.
231 * @errp: Error object.
233 * Asynchronously complete the specified job.
235 void block_job_complete(BlockJob
*job
, Error
**errp
);
239 * @job: The job to get information about.
241 * Return information about a job.
243 BlockJobInfo
*block_job_query(BlockJob
*job
, Error
**errp
);
246 * block_job_user_pause:
247 * @job: The job to be paused.
249 * Asynchronously pause the specified job.
250 * Do not allow a resume until a matching call to block_job_user_resume.
252 void block_job_user_pause(BlockJob
*job
);
256 * @job: The job to query.
258 * Returns true if the job is user-paused.
260 bool block_job_user_paused(BlockJob
*job
);
263 * block_job_user_resume:
264 * @job: The job to be resumed.
266 * Resume the specified job.
267 * Must be paired with a preceding block_job_user_pause.
269 void block_job_user_resume(BlockJob
*job
);
272 * block_job_cancel_sync:
273 * @job: The job to be canceled.
275 * Synchronously cancel the job. The completion callback is called
276 * before the function returns. The job may actually complete
277 * instead of canceling itself; the circumstances under which this
278 * happens depend on the kind of job that is active.
280 * Returns the return value from the job if the job actually completed
281 * during the call, or -ECANCELED if it was canceled.
283 int block_job_cancel_sync(BlockJob
*job
);
286 * block_job_cancel_sync_all:
288 * Synchronously cancels all jobs using block_job_cancel_sync().
290 void block_job_cancel_sync_all(void);
293 * block_job_complete_sync:
294 * @job: The job to be completed.
295 * @errp: Error object which may be set by block_job_complete(); this is not
296 * necessarily set on every error, the job return value has to be
299 * Synchronously complete the job. The completion callback is called before the
300 * function returns, unless it is NULL (which is permissible when using this
303 * Returns the return value from the job.
305 int block_job_complete_sync(BlockJob
*job
, Error
**errp
);
308 * block_job_iostatus_reset:
309 * @job: The job whose I/O status should be reset.
311 * Reset I/O status on @job and on BlockDriverState objects it uses,
312 * other than job->blk.
314 void block_job_iostatus_reset(BlockJob
*job
);
319 * Allocate and return a new block job transaction. Jobs can be added to the
320 * transaction using block_job_txn_add_job().
322 * The transaction is automatically freed when the last job completes or is
325 * All jobs in the transaction either complete successfully or fail/cancel as a
326 * group. Jobs wait for each other before completing. Cancelling one job
327 * cancels all jobs in the transaction.
329 BlockJobTxn
*block_job_txn_new(void);
334 * Add a reference to BlockJob refcnt, it will be decreased with
335 * block_job_unref, and then be freed if it comes to be the last
338 void block_job_ref(BlockJob
*job
);
343 * Release a reference that was previously acquired with block_job_ref
344 * or block_job_create. If it's the last reference to the object, it will be
347 void block_job_unref(BlockJob
*job
);
350 * block_job_txn_unref:
352 * Release a reference that was previously acquired with block_job_txn_add_job
353 * or block_job_txn_new. If it's the last reference to the object, it will be
356 void block_job_txn_unref(BlockJobTxn
*txn
);
359 * block_job_txn_add_job:
360 * @txn: The transaction (may be NULL)
361 * @job: Job to add to the transaction
363 * Add @job to the transaction. The @job must not already be in a transaction.
364 * The caller must call either block_job_txn_unref() or block_job_completed()
365 * to release the reference that is automatically grabbed here.
367 void block_job_txn_add_job(BlockJobTxn
*txn
, BlockJob
*job
);
370 * block_job_is_internal:
371 * @job: The job to determine if it is user-visible or not.
373 * Returns true if the job should not be visible to the management layer.
375 bool block_job_is_internal(BlockJob
*job
);