diff options
Diffstat (limited to 'blockjob.c')
| -rw-r--r-- | blockjob.c | 97 |
1 files changed, 86 insertions, 11 deletions
diff --git a/blockjob.c b/blockjob.c index 01b896b7e7..90c4e262b0 100644 --- a/blockjob.c +++ b/blockjob.c @@ -60,6 +60,49 @@ BlockJob *block_job_next(BlockJob *job) return QLIST_NEXT(job, job_list); } +/* Normally the job runs in its BlockBackend's AioContext. The exception is + * block_job_defer_to_main_loop() where it runs in the QEMU main loop. Code + * that supports both cases uses this helper function. + */ +static AioContext *block_job_get_aio_context(BlockJob *job) +{ + return job->deferred_to_main_loop ? + qemu_get_aio_context() : + blk_get_aio_context(job->blk); +} + +static void block_job_attached_aio_context(AioContext *new_context, + void *opaque) +{ + BlockJob *job = opaque; + + if (job->driver->attached_aio_context) { + job->driver->attached_aio_context(job, new_context); + } + + block_job_resume(job); +} + +static void block_job_detach_aio_context(void *opaque) +{ + BlockJob *job = opaque; + + /* In case the job terminates during aio_poll()... */ + block_job_ref(job); + + block_job_pause(job); + + if (!job->paused) { + /* If job is !job->busy this kicks it into the next pause point. */ + block_job_enter(job); + } + while (!job->paused && !job->completed) { + aio_poll(block_job_get_aio_context(job), true); + } + + block_job_unref(job); +} + void *block_job_create(const BlockJobDriver *driver, BlockDriverState *bs, int64_t speed, BlockCompletionFunc *cb, void *opaque, Error **errp) @@ -92,6 +135,9 @@ void *block_job_create(const BlockJobDriver *driver, BlockDriverState *bs, QLIST_INSERT_HEAD(&block_jobs, job, job_list); + blk_add_aio_context_notifier(blk, block_job_attached_aio_context, + block_job_detach_aio_context, job); + /* Only set speed when necessary to avoid NotSupported error */ if (speed != 0) { Error *local_err = NULL; @@ -117,6 +163,9 @@ void block_job_unref(BlockJob *job) BlockDriverState *bs = blk_bs(job->blk); bs->job = NULL; bdrv_op_unblock_all(bs, job->blocker); + blk_remove_aio_context_notifier(job->blk, + block_job_attached_aio_context, + block_job_detach_aio_context, job); blk_unref(job->blk); error_free(job->blocker); g_free(job->id); @@ -252,11 +301,37 @@ void block_job_pause(BlockJob *job) job->pause_count++; } -bool block_job_is_paused(BlockJob *job) +static bool block_job_should_pause(BlockJob *job) { return job->pause_count > 0; } +void coroutine_fn block_job_pause_point(BlockJob *job) +{ + if (!block_job_should_pause(job)) { + return; + } + if (block_job_is_cancelled(job)) { + return; + } + + if (job->driver->pause) { + job->driver->pause(job); + } + + if (block_job_should_pause(job) && !block_job_is_cancelled(job)) { + job->paused = true; + job->busy = false; + qemu_coroutine_yield(); /* wait for block_job_resume() */ + job->busy = true; + job->paused = false; + } + + if (job->driver->resume) { + job->driver->resume(job); + } +} + void block_job_resume(BlockJob *job) { assert(job->pause_count > 0); @@ -269,7 +344,6 @@ void block_job_resume(BlockJob *job) void block_job_enter(BlockJob *job) { - block_job_iostatus_reset(job); if (job->co && !job->busy) { qemu_coroutine_enter(job->co, NULL); } @@ -278,6 +352,7 @@ void block_job_enter(BlockJob *job) void block_job_cancel(BlockJob *job) { job->cancelled = true; + block_job_iostatus_reset(job); block_job_enter(job); } @@ -311,9 +386,7 @@ static int block_job_finish_sync(BlockJob *job, return -EBUSY; } while (!job->completed) { - aio_poll(job->deferred_to_main_loop ? qemu_get_aio_context() : - blk_get_aio_context(job->blk), - true); + aio_poll(block_job_get_aio_context(job), true); } ret = (job->cancelled && job->ret == 0) ? -ECANCELED : job->ret; block_job_unref(job); @@ -361,14 +434,12 @@ void block_job_sleep_ns(BlockJob *job, QEMUClockType type, int64_t ns) } job->busy = false; - if (!block_job_is_paused(job)) { + if (!block_job_should_pause(job)) { co_aio_sleep_ns(blk_get_aio_context(job->blk), type, ns); } - /* The job can be paused while sleeping, so check this again */ - if (block_job_is_paused(job)) { - qemu_coroutine_yield(); - } job->busy = true; + + block_job_pause_point(job); } void block_job_yield(BlockJob *job) @@ -381,8 +452,12 @@ void block_job_yield(BlockJob *job) } job->busy = false; - qemu_coroutine_yield(); + if (!block_job_should_pause(job)) { + qemu_coroutine_yield(); + } job->busy = true; + + block_job_pause_point(job); } BlockJobInfo *block_job_query(BlockJob *job) |