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/monitor.h"
  30 #include "block/block.h"
  31 #include "block/blockjob.h"
  32 #include "block/block_int.h"
  33 #include "qapi/qmp/qjson.h"
  34 #include "block/coroutine.h"
  35 #include "qmp-commands.h"
  36 #include "qemu/timer.h"
  37 #include "qapi-event.h"
  38
  39 void *block_job_create(const BlockJobDriver *driver, BlockDriverState *bs,
  40                        int64_t speed, BlockDriverCompletionFunc *cb,
  41                        void *opaque, Error **errp)
  42 {
  43     BlockJob *job;
  44
  45     if (bs->job) {
  46         error_set(errp, QERR_DEVICE_IN_USE, bdrv_get_device_name(bs));
  47         return NULL;
  48     }
  49     bdrv_ref(bs);
  50     job = g_malloc0(driver->instance_size);
  51     error_setg(&job->blocker, "block device is in use by block job: %s",
  52                BlockJobType_lookup[driver->job_type]);
  53     bdrv_op_block_all(bs, job->blocker);
  54
  55     job->driver        = driver;
  56     job->bs            = bs;
  57     job->cb            = cb;
  58     job->opaque        = opaque;
  59     job->busy          = true;
  60     bs->job = job;
  61
  62     /* Only set speed when necessary to avoid NotSupported error */
  63     if (speed != 0) {
  64         Error *local_err = NULL;
  65
  66         block_job_set_speed(job, speed, &local_err);
  67         if (local_err) {
  68             bs->job = NULL;
  69             bdrv_op_unblock_all(bs, job->blocker);
  70             error_free(job->blocker);
  71             g_free(job);
  72             error_propagate(errp, local_err);
  73             return NULL;
  74         }
  75     }
  76     return job;
  77 }
  78
  79 void block_job_completed(BlockJob *job, int ret)
  80 {
  81     BlockDriverState *bs = job->bs;
  82
  83     assert(bs->job == job);
  84     job->cb(job->opaque, ret);
  85     bs->job = NULL;
  86     bdrv_op_unblock_all(bs, job->blocker);
  87     error_free(job->blocker);
  88     g_free(job);
  89 }
  90
  91 void block_job_set_speed(BlockJob *job, int64_t speed, Error **errp)
  92 {
  93     Error *local_err = NULL;
  94
  95     if (!job->driver->set_speed) {
  96         error_set(errp, QERR_UNSUPPORTED);
  97         return;
  98     }
  99     job->driver->set_speed(job, speed, &local_err);
 100     if (local_err) {
 101         error_propagate(errp, local_err);
 102         return;
 103     }
 104
 105     job->speed = speed;
 106 }
 107
 108 void block_job_complete(BlockJob *job, Error **errp)
 109 {
 110     if (job->paused || job->cancelled || !job->driver->complete) {
 111         error_set(errp, QERR_BLOCK_JOB_NOT_READY, job->bs->device_name);
 112         return;
 113     }
 114
 115     job->driver->complete(job, errp);
 116 }
 117
 118 void block_job_pause(BlockJob *job)
 119 {
 120     job->paused = true;
 121 }
 122
 123 bool block_job_is_paused(BlockJob *job)
 124 {
 125     return job->paused;
 126 }
 127
 128 void block_job_resume(BlockJob *job)
 129 {
 130     job->paused = false;
 131     block_job_iostatus_reset(job);
 132     if (job->co && !job->busy) {
 133         qemu_coroutine_enter(job->co, NULL);
 134     }
 135 }
 136
 137 void block_job_cancel(BlockJob *job)
 138 {
 139     job->cancelled = true;
 140     block_job_resume(job);
 141 }
 142
 143 bool block_job_is_cancelled(BlockJob *job)
 144 {
 145     return job->cancelled;
 146 }
 147
 148 void block_job_iostatus_reset(BlockJob *job)
 149 {
 150     job->iostatus = BLOCK_DEVICE_IO_STATUS_OK;
 151     if (job->driver->iostatus_reset) {
 152         job->driver->iostatus_reset(job);
 153     }
 154 }
 155
 156 struct BlockCancelData {
 157     BlockJob *job;
 158     BlockDriverCompletionFunc *cb;
 159     void *opaque;
 160     bool cancelled;
 161     int ret;
 162 };
 163
 164 static void block_job_cancel_cb(void *opaque, int ret)
 165 {
 166     struct BlockCancelData *data = opaque;
 167
 168     data->cancelled = block_job_is_cancelled(data->job);
 169     data->ret = ret;
 170     data->cb(data->opaque, ret);
 171 }
 172
 173 int block_job_cancel_sync(BlockJob *job)
 174 {
 175     struct BlockCancelData data;
 176     BlockDriverState *bs = job->bs;
 177
 178     assert(bs->job == job);
 179
 180     /* Set up our own callback to store the result and chain to
 181      * the original callback.
 182      */
 183     data.job = job;
 184     data.cb = job->cb;
 185     data.opaque = job->opaque;
 186     data.ret = -EINPROGRESS;
 187     job->cb = block_job_cancel_cb;
 188     job->opaque = &data;
 189     block_job_cancel(job);
 190     while (data.ret == -EINPROGRESS) {
 191         qemu_aio_wait();
 192     }
 193     return (data.cancelled && data.ret == 0) ? -ECANCELED : data.ret;
 194 }
 195
 196 void block_job_sleep_ns(BlockJob *job, QEMUClockType type, int64_t ns)
 197 {
 198     assert(job->busy);
 199
 200     /* Check cancellation *before* setting busy = false, too!  */
 201     if (block_job_is_cancelled(job)) {
 202         return;
 203     }
 204
 205     job->busy = false;
 206     if (block_job_is_paused(job)) {
 207         qemu_coroutine_yield();
 208     } else {
 209         co_sleep_ns(type, ns);
 210     }
 211     job->busy = true;
 212 }
 213
 214 BlockJobInfo *block_job_query(BlockJob *job)
 215 {
 216     BlockJobInfo *info = g_new0(BlockJobInfo, 1);
 217     info->type      = g_strdup(BlockJobType_lookup[job->driver->job_type]);
 218     info->device    = g_strdup(bdrv_get_device_name(job->bs));
 219     info->len       = job->len;
 220     info->busy      = job->busy;
 221     info->paused    = job->paused;
 222     info->offset    = job->offset;
 223     info->speed     = job->speed;
 224     info->io_status = job->iostatus;
 225     return info;
 226 }
 227
 228 static void block_job_iostatus_set_err(BlockJob *job, int error)
 229 {
 230     if (job->iostatus == BLOCK_DEVICE_IO_STATUS_OK) {
 231         job->iostatus = error == ENOSPC ? BLOCK_DEVICE_IO_STATUS_NOSPACE :
 232                                           BLOCK_DEVICE_IO_STATUS_FAILED;
 233     }
 234 }
 235
 236
 237 QObject *qobject_from_block_job(BlockJob *job)
 238 {
 239     return qobject_from_jsonf("{ 'type': %s,"
 240                               "'device': %s,"
 241                               "'len': %" PRId64 ","
 242                               "'offset': %" PRId64 ","
 243                               "'speed': %" PRId64 " }",
 244                               BlockJobType_lookup[job->driver->job_type],
 245                               bdrv_get_device_name(job->bs),
 246                               job->len,
 247                               job->offset,
 248                               job->speed);
 249 }
 250
 251 void block_job_ready(BlockJob *job)
 252 {
 253     QObject *data = qobject_from_block_job(job);
 254     monitor_protocol_event(QEVENT_BLOCK_JOB_READY, data);
 255     qobject_decref(data);
 256 }
 257
 258 BlockErrorAction block_job_error_action(BlockJob *job, BlockDriverState *bs,
 259                                         BlockdevOnError on_err,
 260                                         int is_read, int error)
 261 {
 262     BlockErrorAction action;
 263
 264     switch (on_err) {
 265     case BLOCKDEV_ON_ERROR_ENOSPC:
 266         action = (error == ENOSPC) ?
 267                  BLOCK_ERROR_ACTION_STOP : BLOCK_ERROR_ACTION_REPORT;
 268         break;
 269     case BLOCKDEV_ON_ERROR_STOP:
 270         action = BLOCK_ERROR_ACTION_STOP;
 271         break;
 272     case BLOCKDEV_ON_ERROR_REPORT:
 273         action = BLOCK_ERROR_ACTION_REPORT;
 274         break;
 275     case BLOCKDEV_ON_ERROR_IGNORE:
 276         action = BLOCK_ERROR_ACTION_IGNORE;
 277         break;
 278     default:
 279         abort();
 280     }
 281     qapi_event_send_block_job_error(bdrv_get_device_name(bs),
 282                                     is_read ? IO_OPERATION_TYPE_READ :
 283                                     IO_OPERATION_TYPE_WRITE,
 284                                     action, &error_abort);
 285     if (action == BLOCK_ERROR_ACTION_STOP) {
 286         block_job_pause(job);
 287         block_job_iostatus_set_err(job, error);
 288         if (bs != job->bs) {
 289             bdrv_iostatus_set_err(bs, error);
 290         }
 291     }
 292     return action;
 293 }