block/create.c

   1 /*
   2  * Block layer code related to image creation
   3  *
   4  * Copyright (c) 2018 Kevin Wolf <kwolf@redhat.com>
   5  *
   6  * Permission is hereby granted, free of charge, to any person obtaining a copy
   7  * of this software and associated documentation files (the "Software"), to deal
   8  * in the Software without restriction, including without limitation the rights
   9  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  10  * copies of the Software, and to permit persons to whom the Software is
  11  * furnished to do so, subject to the following conditions:
  12  *
  13  * The above copyright notice and this permission notice shall be included in
  14  * all copies or substantial portions of the Software.
  15  *
  16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
  19  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  21  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  22  * THE SOFTWARE.
  23  */
  24
  25 #include "qemu/osdep.h"
  26 #include "block/block_int.h"
  27 #include "qemu/job.h"
  28 #include "qapi/qapi-commands-block-core.h"
  29 #include "qapi/qapi-visit-block-core.h"
  30 #include "qapi/clone-visitor.h"
  31 #include "qapi/error.h"
  32
  33 typedef struct BlockdevCreateJob {
  34     Job common;
  35     BlockDriver *drv;
  36     BlockdevCreateOptions *opts;
  37     int ret;
  38     Error *err;
  39 } BlockdevCreateJob;
  40
  41 static void blockdev_create_complete(Job *job, void *opaque)
  42 {
  43     BlockdevCreateJob *s = container_of(job, BlockdevCreateJob, common);
  44
  45     job_completed(job, s->ret, s->err);
  46 }
  47
  48 static void coroutine_fn blockdev_create_run(void *opaque)
  49 {
  50     BlockdevCreateJob *s = opaque;
  51
  52     job_progress_set_remaining(&s->common, 1);
  53     s->ret = s->drv->bdrv_co_create(s->opts, &s->err);
  54     job_progress_update(&s->common, 1);
  55
  56     qapi_free_BlockdevCreateOptions(s->opts);
  57     job_defer_to_main_loop(&s->common, blockdev_create_complete, NULL);
  58 }
  59
  60 static const JobDriver blockdev_create_job_driver = {
  61     .instance_size = sizeof(BlockdevCreateJob),
  62     .job_type      = JOB_TYPE_CREATE,
  63     .start         = blockdev_create_run,
  64 };
  65
  66 void qmp_blockdev_create(const char *job_id, BlockdevCreateOptions *options,
  67                          Error **errp)
  68 {
  69     BlockdevCreateJob *s;
  70     const char *fmt = BlockdevDriver_str(options->driver);
  71     BlockDriver *drv = bdrv_find_format(fmt);
  72
  73     /* If the driver is in the schema, we know that it exists. But it may not
  74      * be whitelisted. */
  75     assert(drv);
  76     if (bdrv_uses_whitelist() && !bdrv_is_whitelisted(drv, false)) {
  77         error_setg(errp, "Driver is not whitelisted");
  78         return;
  79     }
  80
  81     /* Error out if the driver doesn't support .bdrv_co_create */
  82     if (!drv->bdrv_co_create) {
  83         error_setg(errp, "Driver does not support blockdev-create");
  84         return;
  85     }
  86
  87     /* Create the block job */
  88     /* TODO Running in the main context. Block drivers need to error out or add
  89      * locking when they use a BDS in a different AioContext. */
  90     s = job_create(job_id, &blockdev_create_job_driver, NULL,
  91                    qemu_get_aio_context(), JOB_DEFAULT | JOB_MANUAL_DISMISS,
  92                    NULL, NULL, errp);
  93     if (!s) {
  94         return;
  95     }
  96
  97     s->drv = drv,
  98     s->opts = QAPI_CLONE(BlockdevCreateOptions, options),
  99
 100     job_start(&s->common);
 101 }