include/block/blockjob.h

   1 /*
   2  * Declarations for long-running block device operations
   3  *
   4  * Copyright (c) 2011 IBM Corp.
   5  * Copyright (c) 2012 Red Hat, Inc.
   6  *
   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:
  13  *
  14  * The above copyright notice and this permission notice shall be included in
  15  * all copies or substantial portions of the Software.
  16  *
  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.
  24  */
  25
  26 #ifndef BLOCKJOB_H
  27 #define BLOCKJOB_H
  28
  29 #include "qemu/job.h"
  30 #include "block/block.h"
  31 #include "qemu/ratelimit.h"
  32
  33 #define BLOCK_JOB_SLICE_TIME 100000000ULL /* ns */
  34
  35 typedef struct BlockJobDriver BlockJobDriver;
  36
  37 /**
  38  * BlockJob:
  39  *
  40  * Long-running operation on a BlockDriverState.
  41  */
  42 typedef struct BlockJob {
  43     /** Data belonging to the generic Job infrastructure */
  44     Job job;
  45
  46     /** Status that is published by the query-block-jobs QMP API */
  47     BlockDeviceIoStatus iostatus;
  48
  49     /** Speed that was set with @block_job_set_speed.  */
  50     int64_t speed;
  51
  52     /** Rate limiting data structure for implementing @speed. */
  53     RateLimit limit;
  54
  55     /** Block other operations when block job is running */
  56     Error *blocker;
  57
  58     /** Called when a cancelled job is finalised. */
  59     Notifier finalize_cancelled_notifier;
  60
  61     /** Called when a successfully completed job is finalised. */
  62     Notifier finalize_completed_notifier;
  63
  64     /** Called when the job transitions to PENDING */
  65     Notifier pending_notifier;
  66
  67     /** Called when the job transitions to READY */
  68     Notifier ready_notifier;
  69
  70     /** Called when the job coroutine yields or terminates */
  71     Notifier idle_notifier;
  72
  73     /** BlockDriverStates that are involved in this block job */
  74     GSList *nodes;
  75 } BlockJob;
  76
  77 /**
  78  * block_job_next:
  79  * @job: A block job, or %NULL.
  80  *
  81  * Get the next element from the list of block jobs after @job, or the
  82  * first one if @job is %NULL.
  83  *
  84  * Returns the requested job, or %NULL if there are no more jobs left.
  85  */
  86 BlockJob *block_job_next(BlockJob *job);
  87
  88 /**
  89  * block_job_get:
  90  * @id: The id of the block job.
  91  *
  92  * Get the block job identified by @id (which must not be %NULL).
  93  *
  94  * Returns the requested job, or %NULL if it doesn't exist.
  95  */
  96 BlockJob *block_job_get(const char *id);
  97
  98 /**
  99  * block_job_add_bdrv:
 100  * @job: A block job
 101  * @name: The name to assign to the new BdrvChild
 102  * @bs: A BlockDriverState that is involved in @job
 103  * @perm, @shared_perm: Permissions to request on the node
 104  *
 105  * Add @bs to the list of BlockDriverState that are involved in
 106  * @job. This means that all operations will be blocked on @bs while
 107  * @job exists.
 108  */
 109 int block_job_add_bdrv(BlockJob *job, const char *name, BlockDriverState *bs,
 110                        uint64_t perm, uint64_t shared_perm, Error **errp);
 111
 112 /**
 113  * block_job_remove_all_bdrv:
 114  * @job: The block job
 115  *
 116  * Remove all BlockDriverStates from the list of nodes that are involved in the
 117  * job. This removes the blockers added with block_job_add_bdrv().
 118  */
 119 void block_job_remove_all_bdrv(BlockJob *job);
 120
 121 /**
 122  * block_job_has_bdrv:
 123  * @job: The block job
 124  *
 125  * Searches for @bs in the list of nodes that are involved in the
 126  * job.
 127  */
 128 bool block_job_has_bdrv(BlockJob *job, BlockDriverState *bs);
 129
 130 /**
 131  * block_job_set_speed:
 132  * @job: The job to set the speed for.
 133  * @speed: The new value
 134  * @errp: Error object.
 135  *
 136  * Set a rate-limiting parameter for the job; the actual meaning may
 137  * vary depending on the job type.
 138  */
 139 bool block_job_set_speed(BlockJob *job, int64_t speed, Error **errp);
 140
 141 /**
 142  * block_job_query:
 143  * @job: The job to get information about.
 144  *
 145  * Return information about a job.
 146  */
 147 BlockJobInfo *block_job_query(BlockJob *job, Error **errp);
 148
 149 /**
 150  * block_job_iostatus_reset:
 151  * @job: The job whose I/O status should be reset.
 152  *
 153  * Reset I/O status on @job and on BlockDriverState objects it uses,
 154  * other than job->blk.
 155  */
 156 void block_job_iostatus_reset(BlockJob *job);
 157
 158 /**
 159  * block_job_is_internal:
 160  * @job: The job to determine if it is user-visible or not.
 161  *
 162  * Returns true if the job should not be visible to the management layer.
 163  */
 164 bool block_job_is_internal(BlockJob *job);
 165
 166 /**
 167  * block_job_driver:
 168  *
 169  * Returns the driver associated with a block job.
 170  */
 171 const BlockJobDriver *block_job_driver(BlockJob *job);
 172
 173 /*
 174  * block_job_get_aio_context:
 175  *
 176  * Returns aio context associated with a block job.
 177  */
 178 AioContext *block_job_get_aio_context(BlockJob *job);
 179
 180 #endif