blockjob.c

   1 /*
   2  * QEMU System Emulator block driver
   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 #include "config-host.h"
  27 #include "qemu-common.h"
  28 #include "trace.h"
  29 #include "monitor.h"
  30 #include "block.h"
  31 #include "blockjob.h"
  32 #include "block_int.h"
  33 #include "qjson.h"
  34 #include "qemu-coroutine.h"
  35 #include "qmp-commands.h"
  36 #include "qemu-timer.h"
  37
  38 void *block_job_create(const BlockJobType *job_type, BlockDriverState *bs,
  39                        int64_t speed, BlockDriverCompletionFunc *cb,
  40                        void *opaque, Error **errp)
  41 {
  42     BlockJob *job;
  43
  44     if (bs->job || bdrv_in_use(bs)) {
  45         error_set(errp, QERR_DEVICE_IN_USE, bdrv_get_device_name(bs));
  46         return NULL;
  47     }
  48     bdrv_set_in_use(bs, 1);
  49
  50     job = g_malloc0(job_type->instance_size);
  51     job->job_type      = job_type;
  52     job->bs            = bs;
  53     job->cb            = cb;
  54     job->opaque        = opaque;
  55     job->busy          = true;
  56     bs->job = job;
  57
  58     /* Only set speed when necessary to avoid NotSupported error */
  59     if (speed != 0) {
  60         Error *local_err = NULL;
  61
  62         block_job_set_speed(job, speed, &local_err);
  63         if (error_is_set(&local_err)) {
  64             bs->job = NULL;
  65             g_free(job);
  66             bdrv_set_in_use(bs, 0);
  67             error_propagate(errp, local_err);
  68             return NULL;
  69         }
  70     }
  71     return job;
  72 }
  73
  74 void block_job_complete(BlockJob *job, int ret)
  75 {
  76     BlockDriverState *bs = job->bs;
  77
  78     assert(bs->job == job);
  79     job->cb(job->opaque, ret);
  80     bs->job = NULL;
  81     g_free(job);
  82     bdrv_set_in_use(bs, 0);
  83 }
  84
  85 void block_job_set_speed(BlockJob *job, int64_t speed, Error **errp)
  86 {
  87     Error *local_err = NULL;
  88
  89     if (!job->job_type->set_speed) {
  90         error_set(errp, QERR_NOT_SUPPORTED);
  91         return;
  92     }
  93     job->job_type->set_speed(job, speed, &local_err);
  94     if (error_is_set(&local_err)) {
  95         error_propagate(errp, local_err);
  96         return;
  97     }
  98
  99     job->speed = speed;
 100 }
 101
 102 void block_job_pause(BlockJob *job)
 103 {
 104     job->paused = true;
 105 }
 106
 107 bool block_job_is_paused(BlockJob *job)
 108 {
 109     return job->paused;
 110 }
 111
 112 void block_job_resume(BlockJob *job)
 113 {
 114     job->paused = false;
 115     block_job_iostatus_reset(job);
 116     if (job->co && !job->busy) {
 117         qemu_coroutine_enter(job->co, NULL);
 118     }
 119 }
 120
 121 void block_job_cancel(BlockJob *job)
 122 {
 123     job->cancelled = true;
 124     block_job_resume(job);
 125 }
 126
 127 bool block_job_is_cancelled(BlockJob *job)
 128 {
 129     return job->cancelled;
 130 }
 131
 132 void block_job_iostatus_reset(BlockJob *job)
 133 {
 134     job->iostatus = BLOCK_DEVICE_IO_STATUS_OK;
 135 }
 136
 137 struct BlockCancelData {
 138     BlockJob *job;
 139     BlockDriverCompletionFunc *cb;
 140     void *opaque;
 141     bool cancelled;
 142     int ret;
 143 };
 144
 145 static void block_job_cancel_cb(void *opaque, int ret)
 146 {
 147     struct BlockCancelData *data = opaque;
 148
 149     data->cancelled = block_job_is_cancelled(data->job);
 150     data->ret = ret;
 151     data->cb(data->opaque, ret);
 152 }
 153
 154 int block_job_cancel_sync(BlockJob *job)
 155 {
 156     struct BlockCancelData data;
 157     BlockDriverState *bs = job->bs;
 158
 159     assert(bs->job == job);
 160
 161     /* Set up our own callback to store the result and chain to
 162      * the original callback.
 163      */
 164     data.job = job;
 165     data.cb = job->cb;
 166     data.opaque = job->opaque;
 167     data.ret = -EINPROGRESS;
 168     job->cb = block_job_cancel_cb;
 169     job->opaque = &data;
 170     block_job_cancel(job);
 171     while (data.ret == -EINPROGRESS) {
 172         qemu_aio_wait();
 173     }
 174     return (data.cancelled && data.ret == 0) ? -ECANCELED : data.ret;
 175 }
 176
 177 void block_job_sleep_ns(BlockJob *job, QEMUClock *clock, int64_t ns)
 178 {
 179     assert(job->busy);
 180
 181     /* Check cancellation *before* setting busy = false, too!  */
 182     if (block_job_is_cancelled(job)) {
 183         return;
 184     }
 185
 186     job->busy = false;
 187     if (block_job_is_paused(job)) {
 188         qemu_coroutine_yield();
 189     } else {
 190         co_sleep_ns(clock, ns);
 191     }
 192     job->busy = true;
 193 }
 194
 195 BlockJobInfo *block_job_query(BlockJob *job)
 196 {
 197     BlockJobInfo *info = g_new0(BlockJobInfo, 1);
 198     info->type      = g_strdup(job->job_type->job_type);
 199     info->device    = g_strdup(bdrv_get_device_name(job->bs));
 200     info->len       = job->len;
 201     info->busy      = job->busy;
 202     info->paused    = job->paused;
 203     info->offset    = job->offset;
 204     info->speed     = job->speed;
 205     info->io_status = job->iostatus;
 206     return info;
 207 }
 208
 209 static void block_job_iostatus_set_err(BlockJob *job, int error)
 210 {
 211     if (job->iostatus == BLOCK_DEVICE_IO_STATUS_OK) {
 212         job->iostatus = error == ENOSPC ? BLOCK_DEVICE_IO_STATUS_NOSPACE :
 213                                           BLOCK_DEVICE_IO_STATUS_FAILED;
 214     }
 215 }
 216
 217
 218 BlockErrorAction block_job_error_action(BlockJob *job, BlockDriverState *bs,
 219                                         BlockdevOnError on_err,
 220                                         int is_read, int error)
 221 {
 222     BlockErrorAction action;
 223
 224     switch (on_err) {
 225     case BLOCKDEV_ON_ERROR_ENOSPC:
 226         action = (error == ENOSPC) ? BDRV_ACTION_STOP : BDRV_ACTION_REPORT;
 227         break;
 228     case BLOCKDEV_ON_ERROR_STOP:
 229         action = BDRV_ACTION_STOP;
 230         break;
 231     case BLOCKDEV_ON_ERROR_REPORT:
 232         action = BDRV_ACTION_REPORT;
 233         break;
 234     case BLOCKDEV_ON_ERROR_IGNORE:
 235         action = BDRV_ACTION_IGNORE;
 236         break;
 237     default:
 238         abort();
 239     }
 240     bdrv_emit_qmp_error_event(job->bs, QEVENT_BLOCK_JOB_ERROR, action, is_read);
 241     if (action == BDRV_ACTION_STOP) {
 242         block_job_pause(job);
 243         block_job_iostatus_set_err(job, error);
 244         if (bs != job->bs) {
 245             bdrv_iostatus_set_err(bs, error);
 246         }
 247     }
 248     return action;
 249 }