diff options
-rw-r--r-- | blockjob.c | 390 |
1 files changed, 205 insertions, 185 deletions
diff --git a/blockjob.c b/blockjob.c index 85ad610cae..a8ecb41aef 100644 --- a/blockjob.c +++ b/blockjob.c @@ -55,6 +55,21 @@ struct BlockJobTxn { static QLIST_HEAD(, BlockJob) block_jobs = QLIST_HEAD_INITIALIZER(block_jobs); +/* + * The block job API is composed of two categories of functions. + * + * The first includes functions used by the monitor. The monitor is + * peculiar in that it accesses the block job list with block_job_get, and + * therefore needs consistency across block_job_get and the actual operation + * (e.g. block_job_set_speed). The consistency is achieved with + * aio_context_acquire/release. These functions are declared in blockjob.h. + * + * The second includes functions used by the block job drivers and sometimes + * by the core block layer. These do not care about locking, because the + * whole coroutine runs under the AioContext lock, and are declared in + * blockjob_int.h. + */ + BlockJob *block_job_next(BlockJob *job) { if (!job) { @@ -216,90 +231,6 @@ int block_job_add_bdrv(BlockJob *job, const char *name, BlockDriverState *bs, return 0; } -void *block_job_create(const char *job_id, const BlockJobDriver *driver, - BlockDriverState *bs, uint64_t perm, - uint64_t shared_perm, int64_t speed, int flags, - BlockCompletionFunc *cb, void *opaque, Error **errp) -{ - BlockBackend *blk; - BlockJob *job; - int ret; - - if (bs->job) { - error_setg(errp, QERR_DEVICE_IN_USE, bdrv_get_device_name(bs)); - return NULL; - } - - if (job_id == NULL && !(flags & BLOCK_JOB_INTERNAL)) { - job_id = bdrv_get_device_name(bs); - if (!*job_id) { - error_setg(errp, "An explicit job ID is required for this node"); - return NULL; - } - } - - if (job_id) { - if (flags & BLOCK_JOB_INTERNAL) { - error_setg(errp, "Cannot specify job ID for internal block job"); - return NULL; - } - - if (!id_wellformed(job_id)) { - error_setg(errp, "Invalid job ID '%s'", job_id); - return NULL; - } - - if (block_job_get(job_id)) { - error_setg(errp, "Job ID '%s' already in use", job_id); - return NULL; - } - } - - blk = blk_new(perm, shared_perm); - ret = blk_insert_bs(blk, bs, errp); - if (ret < 0) { - blk_unref(blk); - return NULL; - } - - job = g_malloc0(driver->instance_size); - job->driver = driver; - job->id = g_strdup(job_id); - job->blk = blk; - job->cb = cb; - job->opaque = opaque; - job->busy = false; - job->paused = true; - job->pause_count = 1; - job->refcnt = 1; - - error_setg(&job->blocker, "block device is in use by block job: %s", - BlockJobType_lookup[driver->job_type]); - block_job_add_bdrv(job, "main node", bs, 0, BLK_PERM_ALL, &error_abort); - bs->job = job; - - blk_set_dev_ops(blk, &block_job_dev_ops, job); - bdrv_op_unblock(bs, BLOCK_OP_TYPE_DATAPLANE, job->blocker); - - 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; - - block_job_set_speed(job, speed, &local_err); - if (local_err) { - block_job_unref(job); - error_propagate(errp, local_err); - return NULL; - } - } - return job; -} - bool block_job_is_internal(BlockJob *job) { return (job->id == NULL); @@ -334,11 +265,6 @@ void block_job_start(BlockJob *job) bdrv_coroutine_enter(blk_bs(job->blk), job->co); } -void block_job_early_fail(BlockJob *job) -{ - block_job_unref(job); -} - static void block_job_completed_single(BlockJob *job) { if (!job->ret) { @@ -440,21 +366,6 @@ static void block_job_completed_txn_success(BlockJob *job) } } -void block_job_completed(BlockJob *job, int ret) -{ - assert(blk_bs(job->blk)->job == job); - assert(!job->completed); - job->completed = true; - job->ret = ret; - if (!job->txn) { - block_job_completed_single(job); - } else if (ret < 0 || block_job_is_cancelled(job)) { - block_job_completed_txn_abort(job); - } else { - block_job_completed_txn_success(job); - } -} - void block_job_set_speed(BlockJob *job, int64_t speed, Error **errp) { Error *local_err = NULL; @@ -492,44 +403,11 @@ void block_job_user_pause(BlockJob *job) block_job_pause(job); } -static bool block_job_should_pause(BlockJob *job) -{ - return job->pause_count > 0; -} - bool block_job_user_paused(BlockJob *job) { return job->user_paused; } -void coroutine_fn block_job_pause_point(BlockJob *job) -{ - assert(job && block_job_started(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_user_resume(BlockJob *job) { if (job && job->user_paused && job->pause_count > 0) { @@ -538,13 +416,6 @@ void block_job_user_resume(BlockJob *job) } } -void block_job_enter(BlockJob *job) -{ - if (job->co && !job->busy) { - bdrv_coroutine_enter(blk_bs(job->blk), job->co); - } -} - void block_job_cancel(BlockJob *job) { if (block_job_started(job)) { @@ -556,11 +427,6 @@ void block_job_cancel(BlockJob *job) } } -bool block_job_is_cancelled(BlockJob *job) -{ - return job->cancelled; -} - void block_job_iostatus_reset(BlockJob *job) { job->iostatus = BLOCK_DEVICE_IO_STATUS_OK; @@ -628,42 +494,6 @@ int block_job_complete_sync(BlockJob *job, Error **errp) return block_job_finish_sync(job, &block_job_complete, errp); } -void block_job_sleep_ns(BlockJob *job, QEMUClockType type, int64_t ns) -{ - assert(job->busy); - - /* Check cancellation *before* setting busy = false, too! */ - if (block_job_is_cancelled(job)) { - return; - } - - job->busy = false; - if (!block_job_should_pause(job)) { - co_aio_sleep_ns(blk_get_aio_context(job->blk), type, ns); - } - job->busy = true; - - block_job_pause_point(job); -} - -void block_job_yield(BlockJob *job) -{ - assert(job->busy); - - /* Check cancellation *before* setting busy = false, too! */ - if (block_job_is_cancelled(job)) { - return; - } - - job->busy = false; - if (!block_job_should_pause(job)) { - qemu_coroutine_yield(); - } - job->busy = true; - - block_job_pause_point(job); -} - BlockJobInfo *block_job_query(BlockJob *job, Error **errp) { BlockJobInfo *info; @@ -723,6 +553,95 @@ static void block_job_event_completed(BlockJob *job, const char *msg) &error_abort); } +/* + * API for block job drivers and the block layer. These functions are + * declared in blockjob_int.h. + */ + +void *block_job_create(const char *job_id, const BlockJobDriver *driver, + BlockDriverState *bs, uint64_t perm, + uint64_t shared_perm, int64_t speed, int flags, + BlockCompletionFunc *cb, void *opaque, Error **errp) +{ + BlockBackend *blk; + BlockJob *job; + int ret; + + if (bs->job) { + error_setg(errp, QERR_DEVICE_IN_USE, bdrv_get_device_name(bs)); + return NULL; + } + + if (job_id == NULL && !(flags & BLOCK_JOB_INTERNAL)) { + job_id = bdrv_get_device_name(bs); + if (!*job_id) { + error_setg(errp, "An explicit job ID is required for this node"); + return NULL; + } + } + + if (job_id) { + if (flags & BLOCK_JOB_INTERNAL) { + error_setg(errp, "Cannot specify job ID for internal block job"); + return NULL; + } + + if (!id_wellformed(job_id)) { + error_setg(errp, "Invalid job ID '%s'", job_id); + return NULL; + } + + if (block_job_get(job_id)) { + error_setg(errp, "Job ID '%s' already in use", job_id); + return NULL; + } + } + + blk = blk_new(perm, shared_perm); + ret = blk_insert_bs(blk, bs, errp); + if (ret < 0) { + blk_unref(blk); + return NULL; + } + + job = g_malloc0(driver->instance_size); + job->driver = driver; + job->id = g_strdup(job_id); + job->blk = blk; + job->cb = cb; + job->opaque = opaque; + job->busy = false; + job->paused = true; + job->pause_count = 1; + job->refcnt = 1; + + error_setg(&job->blocker, "block device is in use by block job: %s", + BlockJobType_lookup[driver->job_type]); + block_job_add_bdrv(job, "main node", bs, 0, BLK_PERM_ALL, &error_abort); + bs->job = job; + + blk_set_dev_ops(blk, &block_job_dev_ops, job); + bdrv_op_unblock(bs, BLOCK_OP_TYPE_DATAPLANE, job->blocker); + + 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; + + block_job_set_speed(job, speed, &local_err); + if (local_err) { + block_job_unref(job); + error_propagate(errp, local_err); + return NULL; + } + } + return job; +} + void block_job_pause_all(void) { BlockJob *job = NULL; @@ -735,6 +654,59 @@ void block_job_pause_all(void) } } +void block_job_early_fail(BlockJob *job) +{ + block_job_unref(job); +} + +void block_job_completed(BlockJob *job, int ret) +{ + assert(blk_bs(job->blk)->job == job); + assert(!job->completed); + job->completed = true; + job->ret = ret; + if (!job->txn) { + block_job_completed_single(job); + } else if (ret < 0 || block_job_is_cancelled(job)) { + block_job_completed_txn_abort(job); + } else { + block_job_completed_txn_success(job); + } +} + +static bool block_job_should_pause(BlockJob *job) +{ + return job->pause_count > 0; +} + +void coroutine_fn block_job_pause_point(BlockJob *job) +{ + assert(job && block_job_started(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_all(void) { BlockJob *job = NULL; @@ -747,6 +719,54 @@ void block_job_resume_all(void) } } +void block_job_enter(BlockJob *job) +{ + if (job->co && !job->busy) { + bdrv_coroutine_enter(blk_bs(job->blk), job->co); + } +} + +bool block_job_is_cancelled(BlockJob *job) +{ + return job->cancelled; +} + +void block_job_sleep_ns(BlockJob *job, QEMUClockType type, int64_t ns) +{ + assert(job->busy); + + /* Check cancellation *before* setting busy = false, too! */ + if (block_job_is_cancelled(job)) { + return; + } + + job->busy = false; + if (!block_job_should_pause(job)) { + co_aio_sleep_ns(blk_get_aio_context(job->blk), type, ns); + } + job->busy = true; + + block_job_pause_point(job); +} + +void block_job_yield(BlockJob *job) +{ + assert(job->busy); + + /* Check cancellation *before* setting busy = false, too! */ + if (block_job_is_cancelled(job)) { + return; + } + + job->busy = false; + if (!block_job_should_pause(job)) { + qemu_coroutine_yield(); + } + job->busy = true; + + block_job_pause_point(job); +} + void block_job_event_ready(BlockJob *job) { job->ready = true; |