qemu

blockjob.h (6361B)

---

 /*
  * Declarations for long-running block device operations
  *
  * Copyright (c) 2011 IBM Corp.
  * Copyright (c) 2012 Red Hat, Inc.
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
  * in the Software without restriction, including without limitation the rights
  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  * copies of the Software, and to permit persons to whom the Software is
  * furnished to do so, subject to the following conditions:
  *
  * The above copyright notice and this permission notice shall be included in
  * all copies or substantial portions of the Software.
  *
  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */
 
 #ifndef BLOCKJOB_H
 #define BLOCKJOB_H
 
 #include "qemu/job.h"
 #include "block/block.h"
 #include "qemu/ratelimit.h"
 
 #define BLOCK_JOB_SLICE_TIME 100000000ULL /* ns */
 
 typedef struct BlockJobDriver BlockJobDriver;
 
 /**
  * BlockJob:
  *
  * Long-running operation on a BlockDriverState.
  */
 typedef struct BlockJob {
     /**
      * Data belonging to the generic Job infrastructure.
      * Protected by job mutex.
      */
     Job job;
 
     /**
      * Status that is published by the query-block-jobs QMP API.
      * Protected by job mutex.
      */
     BlockDeviceIoStatus iostatus;
 
     /**
      * Speed that was set with @block_job_set_speed.
      * Always modified and read under QEMU global mutex (GLOBAL_STATE_CODE).
      */
     int64_t speed;
 
     /**
      * Rate limiting data structure for implementing @speed.
      * RateLimit API is thread-safe.
      */
     RateLimit limit;
 
     /**
      * Block other operations when block job is running.
      * Always modified and read under QEMU global mutex (GLOBAL_STATE_CODE).
      */
     Error *blocker;
 
     /** All notifiers are set once in block_job_create() and never modified. */
 
     /** Called when a cancelled job is finalised. */
     Notifier finalize_cancelled_notifier;
 
     /** Called when a successfully completed job is finalised. */
     Notifier finalize_completed_notifier;
 
     /** Called when the job transitions to PENDING */
     Notifier pending_notifier;
 
     /** Called when the job transitions to READY */
     Notifier ready_notifier;
 
     /** Called when the job coroutine yields or terminates */
     Notifier idle_notifier;
 
     /**
      * BlockDriverStates that are involved in this block job.
      * Always modified and read under QEMU global mutex (GLOBAL_STATE_CODE).
      */
     GSList *nodes;
 } BlockJob;
 
 /*
  * Global state (GS) API. These functions run under the BQL.
  *
  * See include/block/block-global-state.h for more information about
  * the GS API.
  */
 
 /**
  * block_job_next_locked:
  * @job: A block job, or %NULL.
  *
  * Get the next element from the list of block jobs after @job, or the
  * first one if @job is %NULL.
  *
  * Returns the requested job, or %NULL if there are no more jobs left.
  * Called with job lock held.
  */
 BlockJob *block_job_next_locked(BlockJob *job);
 
 /**
  * block_job_get:
  * @id: The id of the block job.
  *
  * Get the block job identified by @id (which must not be %NULL).
  *
  * Returns the requested job, or %NULL if it doesn't exist.
  * Called with job lock *not* held.
  */
 BlockJob *block_job_get(const char *id);
 
 /* Same as block_job_get(), but called with job lock held. */
 BlockJob *block_job_get_locked(const char *id);
 
 /**
  * block_job_add_bdrv:
  * @job: A block job
  * @name: The name to assign to the new BdrvChild
  * @bs: A BlockDriverState that is involved in @job
  * @perm, @shared_perm: Permissions to request on the node
  *
  * Add @bs to the list of BlockDriverState that are involved in
  * @job. This means that all operations will be blocked on @bs while
  * @job exists.
  */
 int block_job_add_bdrv(BlockJob *job, const char *name, BlockDriverState *bs,
                        uint64_t perm, uint64_t shared_perm, Error **errp);
 
 /**
  * block_job_remove_all_bdrv:
  * @job: The block job
  *
  * Remove all BlockDriverStates from the list of nodes that are involved in the
  * job. This removes the blockers added with block_job_add_bdrv().
  */
 void block_job_remove_all_bdrv(BlockJob *job);
 
 /**
  * block_job_has_bdrv:
  * @job: The block job
  *
  * Searches for @bs in the list of nodes that are involved in the
  * job.
  */
 bool block_job_has_bdrv(BlockJob *job, BlockDriverState *bs);
 
 /**
  * block_job_set_speed_locked:
  * @job: The job to set the speed for.
  * @speed: The new value
  * @errp: Error object.
  *
  * Set a rate-limiting parameter for the job; the actual meaning may
  * vary depending on the job type.
  *
  * Called with job lock held, but might release it temporarily.
  */
 bool block_job_set_speed_locked(BlockJob *job, int64_t speed, Error **errp);
 
 /**
  * block_job_query_locked:
  * @job: The job to get information about.
  *
  * Return information about a job.
  *
  * Called with job lock held.
  */
 BlockJobInfo *block_job_query_locked(BlockJob *job, Error **errp);
 
 /**
  * block_job_iostatus_reset_locked:
  * @job: The job whose I/O status should be reset.
  *
  * Reset I/O status on @job and on BlockDriverState objects it uses,
  * other than job->blk.
  *
  * Called with job lock held.
  */
 void block_job_iostatus_reset_locked(BlockJob *job);
 
 /*
  * block_job_get_aio_context:
  *
  * Returns aio context associated with a block job.
  */
 AioContext *block_job_get_aio_context(BlockJob *job);
 
 
 /*
  * Common functions that are neither I/O nor Global State.
  *
  * See include/block/block-common.h for more information about
  * the Common API.
  */
 
 /**
  * block_job_is_internal:
  * @job: The job to determine if it is user-visible or not.
  *
  * Returns true if the job should not be visible to the management layer.
  */
 bool block_job_is_internal(BlockJob *job);
 
 /**
  * block_job_driver:
  *
  * Returns the driver associated with a block job.
  */
 const BlockJobDriver *block_job_driver(BlockJob *job);
 
 #endif