2 * QEMU System Emulator block driver
4 * Copyright (c) 2011 IBM Corp.
5 * Copyright (c) 2012 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
26 #include "qemu/osdep.h"
27 #include "qemu-common.h"
29 #include "block/block.h"
30 #include "block/blockjob.h"
31 #include "block/block_int.h"
32 #include "sysemu/block-backend.h"
33 #include "qapi/qmp/qerror.h"
34 #include "qapi/qmp/qjson.h"
35 #include "qemu/coroutine.h"
37 #include "qmp-commands.h"
38 #include "qemu/timer.h"
39 #include "qapi-event.h"
41 /* Transactional group of block jobs */
44 /* Is this txn being cancelled? */
48 QLIST_HEAD(, BlockJob
) jobs
;
54 static QLIST_HEAD(, BlockJob
) block_jobs
= QLIST_HEAD_INITIALIZER(block_jobs
);
56 BlockJob
*block_job_next(BlockJob
*job
)
59 return QLIST_FIRST(&block_jobs
);
61 return QLIST_NEXT(job
, job_list
);
64 BlockJob
*block_job_get(const char *id
)
68 QLIST_FOREACH(job
, &block_jobs
, job_list
) {
69 if (job
->id
&& !strcmp(id
, job
->id
)) {
77 static void block_job_attached_aio_context(AioContext
*new_context
,
80 BlockJob
*job
= opaque
;
82 if (job
->driver
->attached_aio_context
) {
83 job
->driver
->attached_aio_context(job
, new_context
);
86 block_job_resume(job
);
89 static void block_job_drain(BlockJob
*job
)
91 /* If job is !job->busy this kicks it into the next pause point. */
95 if (job
->driver
->drain
) {
96 job
->driver
->drain(job
);
100 static void block_job_detach_aio_context(void *opaque
)
102 BlockJob
*job
= opaque
;
104 /* In case the job terminates during aio_poll()... */
107 block_job_pause(job
);
109 while (!job
->paused
&& !job
->completed
) {
110 block_job_drain(job
);
113 block_job_unref(job
);
116 void block_job_add_bdrv(BlockJob
*job
, BlockDriverState
*bs
)
118 job
->nodes
= g_slist_prepend(job
->nodes
, bs
);
120 bdrv_op_block_all(bs
, job
->blocker
);
123 void *block_job_create(const char *job_id
, const BlockJobDriver
*driver
,
124 BlockDriverState
*bs
, int64_t speed
,
125 BlockCompletionFunc
*cb
, void *opaque
, Error
**errp
)
132 error_setg(errp
, QERR_DEVICE_IN_USE
, bdrv_get_device_name(bs
));
136 if (job_id
== NULL
) {
137 job_id
= bdrv_get_device_name(bs
);
139 error_setg(errp
, "An explicit job ID is required for this node");
144 if (!id_wellformed(job_id
)) {
145 error_setg(errp
, "Invalid job ID '%s'", job_id
);
149 if (block_job_get(job_id
)) {
150 error_setg(errp
, "Job ID '%s' already in use", job_id
);
155 blk_insert_bs(blk
, bs
);
157 job
= g_malloc0(driver
->instance_size
);
158 error_setg(&job
->blocker
, "block device is in use by block job: %s",
159 BlockJobType_lookup
[driver
->job_type
]);
160 block_job_add_bdrv(job
, bs
);
161 bdrv_op_unblock(bs
, BLOCK_OP_TYPE_DATAPLANE
, job
->blocker
);
163 job
->driver
= driver
;
164 job
->id
= g_strdup(job_id
);
167 job
->opaque
= opaque
;
172 QLIST_INSERT_HEAD(&block_jobs
, job
, job_list
);
174 blk_add_aio_context_notifier(blk
, block_job_attached_aio_context
,
175 block_job_detach_aio_context
, job
);
177 /* Only set speed when necessary to avoid NotSupported error */
179 Error
*local_err
= NULL
;
181 block_job_set_speed(job
, speed
, &local_err
);
183 block_job_unref(job
);
184 error_propagate(errp
, local_err
);
191 bool block_job_is_internal(BlockJob
*job
)
193 return (job
->id
== NULL
);
196 void block_job_ref(BlockJob
*job
)
201 void block_job_unref(BlockJob
*job
)
203 if (--job
->refcnt
== 0) {
205 BlockDriverState
*bs
= blk_bs(job
->blk
);
207 for (l
= job
->nodes
; l
; l
= l
->next
) {
209 bdrv_op_unblock_all(bs
, job
->blocker
);
212 g_slist_free(job
->nodes
);
213 blk_remove_aio_context_notifier(job
->blk
,
214 block_job_attached_aio_context
,
215 block_job_detach_aio_context
, job
);
217 error_free(job
->blocker
);
219 QLIST_REMOVE(job
, job_list
);
224 static void block_job_completed_single(BlockJob
*job
)
227 if (job
->driver
->commit
) {
228 job
->driver
->commit(job
);
231 if (job
->driver
->abort
) {
232 job
->driver
->abort(job
);
235 job
->cb(job
->opaque
, job
->ret
);
237 block_job_txn_unref(job
->txn
);
239 block_job_unref(job
);
242 static void block_job_completed_txn_abort(BlockJob
*job
)
245 BlockJobTxn
*txn
= job
->txn
;
246 BlockJob
*other_job
, *next
;
250 * We are cancelled by another job, which will handle everything.
254 txn
->aborting
= true;
255 /* We are the first failed job. Cancel other jobs. */
256 QLIST_FOREACH(other_job
, &txn
->jobs
, txn_list
) {
257 ctx
= blk_get_aio_context(other_job
->blk
);
258 aio_context_acquire(ctx
);
260 QLIST_FOREACH(other_job
, &txn
->jobs
, txn_list
) {
261 if (other_job
== job
|| other_job
->completed
) {
262 /* Other jobs are "effectively" cancelled by us, set the status for
263 * them; this job, however, may or may not be cancelled, depending
264 * on the caller, so leave it. */
265 if (other_job
!= job
) {
266 other_job
->cancelled
= true;
270 block_job_cancel_sync(other_job
);
271 assert(other_job
->completed
);
273 QLIST_FOREACH_SAFE(other_job
, &txn
->jobs
, txn_list
, next
) {
274 ctx
= blk_get_aio_context(other_job
->blk
);
275 block_job_completed_single(other_job
);
276 aio_context_release(ctx
);
280 static void block_job_completed_txn_success(BlockJob
*job
)
283 BlockJobTxn
*txn
= job
->txn
;
284 BlockJob
*other_job
, *next
;
286 * Successful completion, see if there are other running jobs in this
289 QLIST_FOREACH(other_job
, &txn
->jobs
, txn_list
) {
290 if (!other_job
->completed
) {
294 /* We are the last completed job, commit the transaction. */
295 QLIST_FOREACH_SAFE(other_job
, &txn
->jobs
, txn_list
, next
) {
296 ctx
= blk_get_aio_context(other_job
->blk
);
297 aio_context_acquire(ctx
);
298 assert(other_job
->ret
== 0);
299 block_job_completed_single(other_job
);
300 aio_context_release(ctx
);
304 void block_job_completed(BlockJob
*job
, int ret
)
306 assert(blk_bs(job
->blk
)->job
== job
);
307 assert(!job
->completed
);
308 job
->completed
= true;
311 block_job_completed_single(job
);
312 } else if (ret
< 0 || block_job_is_cancelled(job
)) {
313 block_job_completed_txn_abort(job
);
315 block_job_completed_txn_success(job
);
319 void block_job_set_speed(BlockJob
*job
, int64_t speed
, Error
**errp
)
321 Error
*local_err
= NULL
;
323 if (!job
->driver
->set_speed
) {
324 error_setg(errp
, QERR_UNSUPPORTED
);
327 job
->driver
->set_speed(job
, speed
, &local_err
);
329 error_propagate(errp
, local_err
);
336 void block_job_complete(BlockJob
*job
, Error
**errp
)
338 /* Should not be reachable via external interface for internal jobs */
340 if (job
->pause_count
|| job
->cancelled
|| !job
->driver
->complete
) {
341 error_setg(errp
, "The active block job '%s' cannot be completed",
346 job
->driver
->complete(job
, errp
);
349 void block_job_pause(BlockJob
*job
)
354 static bool block_job_should_pause(BlockJob
*job
)
356 return job
->pause_count
> 0;
359 void coroutine_fn
block_job_pause_point(BlockJob
*job
)
361 if (!block_job_should_pause(job
)) {
364 if (block_job_is_cancelled(job
)) {
368 if (job
->driver
->pause
) {
369 job
->driver
->pause(job
);
372 if (block_job_should_pause(job
) && !block_job_is_cancelled(job
)) {
375 qemu_coroutine_yield(); /* wait for block_job_resume() */
380 if (job
->driver
->resume
) {
381 job
->driver
->resume(job
);
385 void block_job_resume(BlockJob
*job
)
387 assert(job
->pause_count
> 0);
389 if (job
->pause_count
) {
392 block_job_enter(job
);
395 void block_job_enter(BlockJob
*job
)
397 if (job
->co
&& !job
->busy
) {
398 qemu_coroutine_enter(job
->co
);
402 void block_job_cancel(BlockJob
*job
)
404 job
->cancelled
= true;
405 block_job_iostatus_reset(job
);
406 block_job_enter(job
);
409 bool block_job_is_cancelled(BlockJob
*job
)
411 return job
->cancelled
;
414 void block_job_iostatus_reset(BlockJob
*job
)
416 job
->iostatus
= BLOCK_DEVICE_IO_STATUS_OK
;
417 if (job
->driver
->iostatus_reset
) {
418 job
->driver
->iostatus_reset(job
);
422 static int block_job_finish_sync(BlockJob
*job
,
423 void (*finish
)(BlockJob
*, Error
**errp
),
426 Error
*local_err
= NULL
;
429 assert(blk_bs(job
->blk
)->job
== job
);
433 finish(job
, &local_err
);
435 error_propagate(errp
, local_err
);
436 block_job_unref(job
);
439 /* block_job_drain calls block_job_enter, and it should be enough to
440 * induce progress until the job completes or moves to the main thread.
442 while (!job
->deferred_to_main_loop
&& !job
->completed
) {
443 block_job_drain(job
);
445 while (!job
->completed
) {
446 aio_poll(qemu_get_aio_context(), true);
448 ret
= (job
->cancelled
&& job
->ret
== 0) ? -ECANCELED
: job
->ret
;
449 block_job_unref(job
);
453 /* A wrapper around block_job_cancel() taking an Error ** parameter so it may be
454 * used with block_job_finish_sync() without the need for (rather nasty)
455 * function pointer casts there. */
456 static void block_job_cancel_err(BlockJob
*job
, Error
**errp
)
458 block_job_cancel(job
);
461 int block_job_cancel_sync(BlockJob
*job
)
463 return block_job_finish_sync(job
, &block_job_cancel_err
, NULL
);
466 void block_job_cancel_sync_all(void)
469 AioContext
*aio_context
;
471 while ((job
= QLIST_FIRST(&block_jobs
))) {
472 aio_context
= blk_get_aio_context(job
->blk
);
473 aio_context_acquire(aio_context
);
474 block_job_cancel_sync(job
);
475 aio_context_release(aio_context
);
479 int block_job_complete_sync(BlockJob
*job
, Error
**errp
)
481 return block_job_finish_sync(job
, &block_job_complete
, errp
);
484 void block_job_sleep_ns(BlockJob
*job
, QEMUClockType type
, int64_t ns
)
488 /* Check cancellation *before* setting busy = false, too! */
489 if (block_job_is_cancelled(job
)) {
494 if (!block_job_should_pause(job
)) {
495 co_aio_sleep_ns(blk_get_aio_context(job
->blk
), type
, ns
);
499 block_job_pause_point(job
);
502 void block_job_yield(BlockJob
*job
)
506 /* Check cancellation *before* setting busy = false, too! */
507 if (block_job_is_cancelled(job
)) {
512 if (!block_job_should_pause(job
)) {
513 qemu_coroutine_yield();
517 block_job_pause_point(job
);
520 BlockJobInfo
*block_job_query(BlockJob
*job
, Error
**errp
)
524 if (block_job_is_internal(job
)) {
525 error_setg(errp
, "Cannot query QEMU internal jobs");
528 info
= g_new0(BlockJobInfo
, 1);
529 info
->type
= g_strdup(BlockJobType_lookup
[job
->driver
->job_type
]);
530 info
->device
= g_strdup(job
->id
);
531 info
->len
= job
->len
;
532 info
->busy
= job
->busy
;
533 info
->paused
= job
->pause_count
> 0;
534 info
->offset
= job
->offset
;
535 info
->speed
= job
->speed
;
536 info
->io_status
= job
->iostatus
;
537 info
->ready
= job
->ready
;
541 static void block_job_iostatus_set_err(BlockJob
*job
, int error
)
543 if (job
->iostatus
== BLOCK_DEVICE_IO_STATUS_OK
) {
544 job
->iostatus
= error
== ENOSPC
? BLOCK_DEVICE_IO_STATUS_NOSPACE
:
545 BLOCK_DEVICE_IO_STATUS_FAILED
;
549 void block_job_event_cancelled(BlockJob
*job
)
551 if (block_job_is_internal(job
)) {
555 qapi_event_send_block_job_cancelled(job
->driver
->job_type
,
563 void block_job_event_completed(BlockJob
*job
, const char *msg
)
565 if (block_job_is_internal(job
)) {
569 qapi_event_send_block_job_completed(job
->driver
->job_type
,
579 void block_job_event_ready(BlockJob
*job
)
583 if (block_job_is_internal(job
)) {
587 qapi_event_send_block_job_ready(job
->driver
->job_type
,
591 job
->speed
, &error_abort
);
594 BlockErrorAction
block_job_error_action(BlockJob
*job
, BlockdevOnError on_err
,
595 int is_read
, int error
)
597 BlockErrorAction action
;
600 case BLOCKDEV_ON_ERROR_ENOSPC
:
601 case BLOCKDEV_ON_ERROR_AUTO
:
602 action
= (error
== ENOSPC
) ?
603 BLOCK_ERROR_ACTION_STOP
: BLOCK_ERROR_ACTION_REPORT
;
605 case BLOCKDEV_ON_ERROR_STOP
:
606 action
= BLOCK_ERROR_ACTION_STOP
;
608 case BLOCKDEV_ON_ERROR_REPORT
:
609 action
= BLOCK_ERROR_ACTION_REPORT
;
611 case BLOCKDEV_ON_ERROR_IGNORE
:
612 action
= BLOCK_ERROR_ACTION_IGNORE
;
617 if (!block_job_is_internal(job
)) {
618 qapi_event_send_block_job_error(job
->id
,
619 is_read
? IO_OPERATION_TYPE_READ
:
620 IO_OPERATION_TYPE_WRITE
,
621 action
, &error_abort
);
623 if (action
== BLOCK_ERROR_ACTION_STOP
) {
624 /* make the pause user visible, which will be resumed from QMP. */
625 job
->user_paused
= true;
626 block_job_pause(job
);
627 block_job_iostatus_set_err(job
, error
);
634 AioContext
*aio_context
;
635 BlockJobDeferToMainLoopFn
*fn
;
637 } BlockJobDeferToMainLoopData
;
639 static void block_job_defer_to_main_loop_bh(void *opaque
)
641 BlockJobDeferToMainLoopData
*data
= opaque
;
642 AioContext
*aio_context
;
644 /* Prevent race with block_job_defer_to_main_loop() */
645 aio_context_acquire(data
->aio_context
);
647 /* Fetch BDS AioContext again, in case it has changed */
648 aio_context
= blk_get_aio_context(data
->job
->blk
);
649 aio_context_acquire(aio_context
);
651 data
->job
->deferred_to_main_loop
= false;
652 data
->fn(data
->job
, data
->opaque
);
654 aio_context_release(aio_context
);
656 aio_context_release(data
->aio_context
);
661 void block_job_defer_to_main_loop(BlockJob
*job
,
662 BlockJobDeferToMainLoopFn
*fn
,
665 BlockJobDeferToMainLoopData
*data
= g_malloc(sizeof(*data
));
667 data
->aio_context
= blk_get_aio_context(job
->blk
);
669 data
->opaque
= opaque
;
670 job
->deferred_to_main_loop
= true;
672 aio_bh_schedule_oneshot(qemu_get_aio_context(),
673 block_job_defer_to_main_loop_bh
, data
);
676 BlockJobTxn
*block_job_txn_new(void)
678 BlockJobTxn
*txn
= g_new0(BlockJobTxn
, 1);
679 QLIST_INIT(&txn
->jobs
);
684 static void block_job_txn_ref(BlockJobTxn
*txn
)
689 void block_job_txn_unref(BlockJobTxn
*txn
)
691 if (txn
&& --txn
->refcnt
== 0) {
696 void block_job_txn_add_job(BlockJobTxn
*txn
, BlockJob
*job
)
705 QLIST_INSERT_HEAD(&txn
->jobs
, job
, txn_list
);
706 block_job_txn_ref(txn
);