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 "qapi/qapi-types-block-core.h" 30 #include "qemu/job.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 /** 44 * Data belonging to the generic Job infrastructure. 45 * Protected by job mutex. 46 */ 47 Job job; 48 49 /** 50 * Status that is published by the query-block-jobs QMP API. 51 * Protected by job mutex. 52 */ 53 BlockDeviceIoStatus iostatus; 54 55 /** 56 * Speed that was set with @block_job_set_speed. 57 * Always modified and read under the BQL (GLOBAL_STATE_CODE). 58 */ 59 int64_t speed; 60 61 /** 62 * Rate limiting data structure for implementing @speed. 63 * RateLimit API is thread-safe. 64 */ 65 RateLimit limit; 66 67 /** 68 * Block other operations when block job is running. 69 * Always modified and read under the BQL (GLOBAL_STATE_CODE). 70 */ 71 Error *blocker; 72 73 /** All notifiers are set once in block_job_create() and never modified. */ 74 75 /** Called when a cancelled job is finalised. */ 76 Notifier finalize_cancelled_notifier; 77 78 /** Called when a successfully completed job is finalised. */ 79 Notifier finalize_completed_notifier; 80 81 /** Called when the job transitions to PENDING */ 82 Notifier pending_notifier; 83 84 /** Called when the job transitions to READY */ 85 Notifier ready_notifier; 86 87 /** Called when the job coroutine yields or terminates */ 88 Notifier idle_notifier; 89 90 /** 91 * BlockDriverStates that are involved in this block job. 92 * Always modified and read under the BQL (GLOBAL_STATE_CODE). 93 */ 94 GSList *nodes; 95 } BlockJob; 96 97 /* 98 * Global state (GS) API. These functions run under the BQL. 99 * 100 * See include/block/block-global-state.h for more information about 101 * the GS API. 102 */ 103 104 /** 105 * block_job_next_locked: 106 * @job: A block job, or %NULL. 107 * 108 * Get the next element from the list of block jobs after @job, or the 109 * first one if @job is %NULL. 110 * 111 * Returns the requested job, or %NULL if there are no more jobs left. 112 * Called with job lock held. 113 */ 114 BlockJob *block_job_next_locked(BlockJob *job); 115 116 /** 117 * block_job_get: 118 * @id: The id of the block job. 119 * 120 * Get the block job identified by @id (which must not be %NULL). 121 * 122 * Returns the requested job, or %NULL if it doesn't exist. 123 * Called with job lock *not* held. 124 */ 125 BlockJob *block_job_get(const char *id); 126 127 /* Same as block_job_get(), but called with job lock held. */ 128 BlockJob *block_job_get_locked(const char *id); 129 130 /** 131 * block_job_add_bdrv: 132 * @job: A block job 133 * @name: The name to assign to the new BdrvChild 134 * @bs: A BlockDriverState that is involved in @job 135 * @perm, @shared_perm: Permissions to request on the node 136 * 137 * Add @bs to the list of BlockDriverState that are involved in 138 * @job. This means that all operations will be blocked on @bs while 139 * @job exists. 140 * 141 * All block nodes must be drained. 142 */ 143 int GRAPH_WRLOCK 144 block_job_add_bdrv(BlockJob *job, const char *name, BlockDriverState *bs, 145 uint64_t perm, uint64_t shared_perm, Error **errp); 146 147 /** 148 * block_job_remove_all_bdrv: 149 * @job: The block job 150 * 151 * Remove all BlockDriverStates from the list of nodes that are involved in the 152 * job. This removes the blockers added with block_job_add_bdrv(). 153 */ 154 void block_job_remove_all_bdrv(BlockJob *job); 155 156 /** 157 * block_job_has_bdrv: 158 * @job: The block job 159 * 160 * Searches for @bs in the list of nodes that are involved in the 161 * job. 162 */ 163 bool block_job_has_bdrv(BlockJob *job, BlockDriverState *bs); 164 165 /** 166 * block_job_set_speed_locked: 167 * @job: The job to set the speed for. 168 * @speed: The new value 169 * @errp: Error object. 170 * 171 * Set a rate-limiting parameter for the job; the actual meaning may 172 * vary depending on the job type. 173 * 174 * Called with job lock held, but might release it temporarily. 175 */ 176 bool block_job_set_speed_locked(BlockJob *job, int64_t speed, Error **errp); 177 178 /** 179 * block_job_change_locked: 180 * @job: The job to change. 181 * @opts: The new options. 182 * @errp: Error object. 183 * 184 * Change the job according to opts. 185 */ 186 void block_job_change_locked(BlockJob *job, BlockJobChangeOptions *opts, 187 Error **errp); 188 189 /** 190 * block_job_query_locked: 191 * @job: The job to get information about. 192 * 193 * Return information about a job. 194 * 195 * Called with job lock held. 196 */ 197 BlockJobInfo *block_job_query_locked(BlockJob *job, Error **errp); 198 199 /** 200 * block_job_iostatus_reset_locked: 201 * @job: The job whose I/O status should be reset. 202 * 203 * Reset I/O status on @job and on BlockDriverState objects it uses, 204 * other than job->blk. 205 * 206 * Called with job lock held. 207 */ 208 void block_job_iostatus_reset_locked(BlockJob *job); 209 210 /* 211 * block_job_get_aio_context: 212 * 213 * Returns aio context associated with a block job. 214 */ 215 AioContext *block_job_get_aio_context(BlockJob *job); 216 217 218 /* 219 * Common functions that are neither I/O nor Global State. 220 * 221 * See include/block/block-common.h for more information about 222 * the Common API. 223 */ 224 225 /** 226 * block_job_is_internal: 227 * @job: The job to determine if it is user-visible or not. 228 * 229 * Returns true if the job should not be visible to the management layer. 230 */ 231 bool block_job_is_internal(BlockJob *job); 232 233 /** 234 * block_job_driver: 235 * 236 * Returns the driver associated with a block job. 237 */ 238 const BlockJobDriver *block_job_driver(BlockJob *job); 239 240 #endif 241