tcg: Add atomic128 helpers
[qemu/ar7.git] / blockjob.c
blob43fecbe13ee4cb0c3314ca7a9d992b12ff208468
1 /*
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
23 * THE SOFTWARE.
26 #include "qemu/osdep.h"
27 #include "qemu-common.h"
28 #include "trace.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"
36 #include "qemu/id.h"
37 #include "qmp-commands.h"
38 #include "qemu/timer.h"
39 #include "qapi-event.h"
41 /* Transactional group of block jobs */
42 struct BlockJobTxn {
44 /* Is this txn being cancelled? */
45 bool aborting;
47 /* List of jobs */
48 QLIST_HEAD(, BlockJob) jobs;
50 /* Reference count */
51 int refcnt;
54 static QLIST_HEAD(, BlockJob) block_jobs = QLIST_HEAD_INITIALIZER(block_jobs);
56 BlockJob *block_job_next(BlockJob *job)
58 if (!job) {
59 return QLIST_FIRST(&block_jobs);
61 return QLIST_NEXT(job, job_list);
64 BlockJob *block_job_get(const char *id)
66 BlockJob *job;
68 QLIST_FOREACH(job, &block_jobs, job_list) {
69 if (!strcmp(id, job->id)) {
70 return job;
74 return NULL;
77 /* Normally the job runs in its BlockBackend's AioContext. The exception is
78 * block_job_defer_to_main_loop() where it runs in the QEMU main loop. Code
79 * that supports both cases uses this helper function.
81 static AioContext *block_job_get_aio_context(BlockJob *job)
83 return job->deferred_to_main_loop ?
84 qemu_get_aio_context() :
85 blk_get_aio_context(job->blk);
88 static void block_job_attached_aio_context(AioContext *new_context,
89 void *opaque)
91 BlockJob *job = opaque;
93 if (job->driver->attached_aio_context) {
94 job->driver->attached_aio_context(job, new_context);
97 block_job_resume(job);
100 static void block_job_detach_aio_context(void *opaque)
102 BlockJob *job = opaque;
104 /* In case the job terminates during aio_poll()... */
105 block_job_ref(job);
107 block_job_pause(job);
109 if (!job->paused) {
110 /* If job is !job->busy this kicks it into the next pause point. */
111 block_job_enter(job);
113 while (!job->paused && !job->completed) {
114 aio_poll(block_job_get_aio_context(job), true);
117 block_job_unref(job);
120 void *block_job_create(const char *job_id, const BlockJobDriver *driver,
121 BlockDriverState *bs, int64_t speed,
122 BlockCompletionFunc *cb, void *opaque, Error **errp)
124 BlockBackend *blk;
125 BlockJob *job;
127 assert(cb);
128 if (bs->job) {
129 error_setg(errp, QERR_DEVICE_IN_USE, bdrv_get_device_name(bs));
130 return NULL;
133 if (job_id == NULL) {
134 job_id = bdrv_get_device_name(bs);
135 if (!*job_id) {
136 error_setg(errp, "An explicit job ID is required for this node");
137 return NULL;
141 if (!id_wellformed(job_id)) {
142 error_setg(errp, "Invalid job ID '%s'", job_id);
143 return NULL;
146 if (block_job_get(job_id)) {
147 error_setg(errp, "Job ID '%s' already in use", job_id);
148 return NULL;
151 blk = blk_new();
152 blk_insert_bs(blk, bs);
154 job = g_malloc0(driver->instance_size);
155 error_setg(&job->blocker, "block device is in use by block job: %s",
156 BlockJobType_lookup[driver->job_type]);
157 bdrv_op_block_all(bs, job->blocker);
158 bdrv_op_unblock(bs, BLOCK_OP_TYPE_DATAPLANE, job->blocker);
160 job->driver = driver;
161 job->id = g_strdup(job_id);
162 job->blk = blk;
163 job->cb = cb;
164 job->opaque = opaque;
165 job->busy = true;
166 job->refcnt = 1;
167 bs->job = job;
169 QLIST_INSERT_HEAD(&block_jobs, job, job_list);
171 blk_add_aio_context_notifier(blk, block_job_attached_aio_context,
172 block_job_detach_aio_context, job);
174 /* Only set speed when necessary to avoid NotSupported error */
175 if (speed != 0) {
176 Error *local_err = NULL;
178 block_job_set_speed(job, speed, &local_err);
179 if (local_err) {
180 block_job_unref(job);
181 error_propagate(errp, local_err);
182 return NULL;
185 return job;
188 void block_job_ref(BlockJob *job)
190 ++job->refcnt;
193 void block_job_unref(BlockJob *job)
195 if (--job->refcnt == 0) {
196 BlockDriverState *bs = blk_bs(job->blk);
197 bs->job = NULL;
198 bdrv_op_unblock_all(bs, job->blocker);
199 blk_remove_aio_context_notifier(job->blk,
200 block_job_attached_aio_context,
201 block_job_detach_aio_context, job);
202 blk_unref(job->blk);
203 error_free(job->blocker);
204 g_free(job->id);
205 QLIST_REMOVE(job, job_list);
206 g_free(job);
210 static void block_job_completed_single(BlockJob *job)
212 if (!job->ret) {
213 if (job->driver->commit) {
214 job->driver->commit(job);
216 } else {
217 if (job->driver->abort) {
218 job->driver->abort(job);
221 job->cb(job->opaque, job->ret);
222 if (job->txn) {
223 block_job_txn_unref(job->txn);
225 block_job_unref(job);
228 static void block_job_completed_txn_abort(BlockJob *job)
230 AioContext *ctx;
231 BlockJobTxn *txn = job->txn;
232 BlockJob *other_job, *next;
234 if (txn->aborting) {
236 * We are cancelled by another job, which will handle everything.
238 return;
240 txn->aborting = true;
241 /* We are the first failed job. Cancel other jobs. */
242 QLIST_FOREACH(other_job, &txn->jobs, txn_list) {
243 ctx = blk_get_aio_context(other_job->blk);
244 aio_context_acquire(ctx);
246 QLIST_FOREACH(other_job, &txn->jobs, txn_list) {
247 if (other_job == job || other_job->completed) {
248 /* Other jobs are "effectively" cancelled by us, set the status for
249 * them; this job, however, may or may not be cancelled, depending
250 * on the caller, so leave it. */
251 if (other_job != job) {
252 other_job->cancelled = true;
254 continue;
256 block_job_cancel_sync(other_job);
257 assert(other_job->completed);
259 QLIST_FOREACH_SAFE(other_job, &txn->jobs, txn_list, next) {
260 ctx = blk_get_aio_context(other_job->blk);
261 block_job_completed_single(other_job);
262 aio_context_release(ctx);
266 static void block_job_completed_txn_success(BlockJob *job)
268 AioContext *ctx;
269 BlockJobTxn *txn = job->txn;
270 BlockJob *other_job, *next;
272 * Successful completion, see if there are other running jobs in this
273 * txn.
275 QLIST_FOREACH(other_job, &txn->jobs, txn_list) {
276 if (!other_job->completed) {
277 return;
280 /* We are the last completed job, commit the transaction. */
281 QLIST_FOREACH_SAFE(other_job, &txn->jobs, txn_list, next) {
282 ctx = blk_get_aio_context(other_job->blk);
283 aio_context_acquire(ctx);
284 assert(other_job->ret == 0);
285 block_job_completed_single(other_job);
286 aio_context_release(ctx);
290 void block_job_completed(BlockJob *job, int ret)
292 assert(blk_bs(job->blk)->job == job);
293 assert(!job->completed);
294 job->completed = true;
295 job->ret = ret;
296 if (!job->txn) {
297 block_job_completed_single(job);
298 } else if (ret < 0 || block_job_is_cancelled(job)) {
299 block_job_completed_txn_abort(job);
300 } else {
301 block_job_completed_txn_success(job);
305 void block_job_set_speed(BlockJob *job, int64_t speed, Error **errp)
307 Error *local_err = NULL;
309 if (!job->driver->set_speed) {
310 error_setg(errp, QERR_UNSUPPORTED);
311 return;
313 job->driver->set_speed(job, speed, &local_err);
314 if (local_err) {
315 error_propagate(errp, local_err);
316 return;
319 job->speed = speed;
322 void block_job_complete(BlockJob *job, Error **errp)
324 if (job->pause_count || job->cancelled || !job->driver->complete) {
325 error_setg(errp, "The active block job '%s' cannot be completed",
326 job->id);
327 return;
330 job->driver->complete(job, errp);
333 void block_job_pause(BlockJob *job)
335 job->pause_count++;
338 static bool block_job_should_pause(BlockJob *job)
340 return job->pause_count > 0;
343 void coroutine_fn block_job_pause_point(BlockJob *job)
345 if (!block_job_should_pause(job)) {
346 return;
348 if (block_job_is_cancelled(job)) {
349 return;
352 if (job->driver->pause) {
353 job->driver->pause(job);
356 if (block_job_should_pause(job) && !block_job_is_cancelled(job)) {
357 job->paused = true;
358 job->busy = false;
359 qemu_coroutine_yield(); /* wait for block_job_resume() */
360 job->busy = true;
361 job->paused = false;
364 if (job->driver->resume) {
365 job->driver->resume(job);
369 void block_job_resume(BlockJob *job)
371 assert(job->pause_count > 0);
372 job->pause_count--;
373 if (job->pause_count) {
374 return;
376 block_job_enter(job);
379 void block_job_enter(BlockJob *job)
381 if (job->co && !job->busy) {
382 qemu_coroutine_enter(job->co);
386 void block_job_cancel(BlockJob *job)
388 job->cancelled = true;
389 block_job_iostatus_reset(job);
390 block_job_enter(job);
393 bool block_job_is_cancelled(BlockJob *job)
395 return job->cancelled;
398 void block_job_iostatus_reset(BlockJob *job)
400 job->iostatus = BLOCK_DEVICE_IO_STATUS_OK;
401 if (job->driver->iostatus_reset) {
402 job->driver->iostatus_reset(job);
406 static int block_job_finish_sync(BlockJob *job,
407 void (*finish)(BlockJob *, Error **errp),
408 Error **errp)
410 Error *local_err = NULL;
411 int ret;
413 assert(blk_bs(job->blk)->job == job);
415 block_job_ref(job);
416 finish(job, &local_err);
417 if (local_err) {
418 error_propagate(errp, local_err);
419 block_job_unref(job);
420 return -EBUSY;
422 while (!job->completed) {
423 aio_poll(block_job_get_aio_context(job), true);
425 ret = (job->cancelled && job->ret == 0) ? -ECANCELED : job->ret;
426 block_job_unref(job);
427 return ret;
430 /* A wrapper around block_job_cancel() taking an Error ** parameter so it may be
431 * used with block_job_finish_sync() without the need for (rather nasty)
432 * function pointer casts there. */
433 static void block_job_cancel_err(BlockJob *job, Error **errp)
435 block_job_cancel(job);
438 int block_job_cancel_sync(BlockJob *job)
440 return block_job_finish_sync(job, &block_job_cancel_err, NULL);
443 void block_job_cancel_sync_all(void)
445 BlockJob *job;
446 AioContext *aio_context;
448 while ((job = QLIST_FIRST(&block_jobs))) {
449 aio_context = blk_get_aio_context(job->blk);
450 aio_context_acquire(aio_context);
451 block_job_cancel_sync(job);
452 aio_context_release(aio_context);
456 int block_job_complete_sync(BlockJob *job, Error **errp)
458 return block_job_finish_sync(job, &block_job_complete, errp);
461 void block_job_sleep_ns(BlockJob *job, QEMUClockType type, int64_t ns)
463 assert(job->busy);
465 /* Check cancellation *before* setting busy = false, too! */
466 if (block_job_is_cancelled(job)) {
467 return;
470 job->busy = false;
471 if (!block_job_should_pause(job)) {
472 co_aio_sleep_ns(blk_get_aio_context(job->blk), type, ns);
474 job->busy = true;
476 block_job_pause_point(job);
479 void block_job_yield(BlockJob *job)
481 assert(job->busy);
483 /* Check cancellation *before* setting busy = false, too! */
484 if (block_job_is_cancelled(job)) {
485 return;
488 job->busy = false;
489 if (!block_job_should_pause(job)) {
490 qemu_coroutine_yield();
492 job->busy = true;
494 block_job_pause_point(job);
497 BlockJobInfo *block_job_query(BlockJob *job)
499 BlockJobInfo *info = g_new0(BlockJobInfo, 1);
500 info->type = g_strdup(BlockJobType_lookup[job->driver->job_type]);
501 info->device = g_strdup(job->id);
502 info->len = job->len;
503 info->busy = job->busy;
504 info->paused = job->pause_count > 0;
505 info->offset = job->offset;
506 info->speed = job->speed;
507 info->io_status = job->iostatus;
508 info->ready = job->ready;
509 return info;
512 static void block_job_iostatus_set_err(BlockJob *job, int error)
514 if (job->iostatus == BLOCK_DEVICE_IO_STATUS_OK) {
515 job->iostatus = error == ENOSPC ? BLOCK_DEVICE_IO_STATUS_NOSPACE :
516 BLOCK_DEVICE_IO_STATUS_FAILED;
520 void block_job_event_cancelled(BlockJob *job)
522 qapi_event_send_block_job_cancelled(job->driver->job_type,
523 job->id,
524 job->len,
525 job->offset,
526 job->speed,
527 &error_abort);
530 void block_job_event_completed(BlockJob *job, const char *msg)
532 qapi_event_send_block_job_completed(job->driver->job_type,
533 job->id,
534 job->len,
535 job->offset,
536 job->speed,
537 !!msg,
538 msg,
539 &error_abort);
542 void block_job_event_ready(BlockJob *job)
544 job->ready = true;
546 qapi_event_send_block_job_ready(job->driver->job_type,
547 job->id,
548 job->len,
549 job->offset,
550 job->speed, &error_abort);
553 BlockErrorAction block_job_error_action(BlockJob *job, BlockdevOnError on_err,
554 int is_read, int error)
556 BlockErrorAction action;
558 switch (on_err) {
559 case BLOCKDEV_ON_ERROR_ENOSPC:
560 case BLOCKDEV_ON_ERROR_AUTO:
561 action = (error == ENOSPC) ?
562 BLOCK_ERROR_ACTION_STOP : BLOCK_ERROR_ACTION_REPORT;
563 break;
564 case BLOCKDEV_ON_ERROR_STOP:
565 action = BLOCK_ERROR_ACTION_STOP;
566 break;
567 case BLOCKDEV_ON_ERROR_REPORT:
568 action = BLOCK_ERROR_ACTION_REPORT;
569 break;
570 case BLOCKDEV_ON_ERROR_IGNORE:
571 action = BLOCK_ERROR_ACTION_IGNORE;
572 break;
573 default:
574 abort();
576 qapi_event_send_block_job_error(job->id,
577 is_read ? IO_OPERATION_TYPE_READ :
578 IO_OPERATION_TYPE_WRITE,
579 action, &error_abort);
580 if (action == BLOCK_ERROR_ACTION_STOP) {
581 /* make the pause user visible, which will be resumed from QMP. */
582 job->user_paused = true;
583 block_job_pause(job);
584 block_job_iostatus_set_err(job, error);
586 return action;
589 typedef struct {
590 BlockJob *job;
591 AioContext *aio_context;
592 BlockJobDeferToMainLoopFn *fn;
593 void *opaque;
594 } BlockJobDeferToMainLoopData;
596 static void block_job_defer_to_main_loop_bh(void *opaque)
598 BlockJobDeferToMainLoopData *data = opaque;
599 AioContext *aio_context;
601 /* Prevent race with block_job_defer_to_main_loop() */
602 aio_context_acquire(data->aio_context);
604 /* Fetch BDS AioContext again, in case it has changed */
605 aio_context = blk_get_aio_context(data->job->blk);
606 aio_context_acquire(aio_context);
608 data->job->deferred_to_main_loop = false;
609 data->fn(data->job, data->opaque);
611 aio_context_release(aio_context);
613 aio_context_release(data->aio_context);
615 g_free(data);
618 void block_job_defer_to_main_loop(BlockJob *job,
619 BlockJobDeferToMainLoopFn *fn,
620 void *opaque)
622 BlockJobDeferToMainLoopData *data = g_malloc(sizeof(*data));
623 data->job = job;
624 data->aio_context = blk_get_aio_context(job->blk);
625 data->fn = fn;
626 data->opaque = opaque;
627 job->deferred_to_main_loop = true;
629 aio_bh_schedule_oneshot(qemu_get_aio_context(),
630 block_job_defer_to_main_loop_bh, data);
633 BlockJobTxn *block_job_txn_new(void)
635 BlockJobTxn *txn = g_new0(BlockJobTxn, 1);
636 QLIST_INIT(&txn->jobs);
637 txn->refcnt = 1;
638 return txn;
641 static void block_job_txn_ref(BlockJobTxn *txn)
643 txn->refcnt++;
646 void block_job_txn_unref(BlockJobTxn *txn)
648 if (txn && --txn->refcnt == 0) {
649 g_free(txn);
653 void block_job_txn_add_job(BlockJobTxn *txn, BlockJob *job)
655 if (!txn) {
656 return;
659 assert(!job->txn);
660 job->txn = txn;
662 QLIST_INSERT_HEAD(&txn->jobs, job, txn_list);
663 block_job_txn_ref(txn);