LXR qemu/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 "qemu/main-loop.h"
  29#include "qapi/qapi-commands-block-core.h"
  30#include "qapi/qapi-visit-block-core.h"
  31#include "qapi/clone-visitor.h"
  32#include "qapi/error.h"
  33
  34typedef struct BlockdevCreateJob {
  35    Job common;
  36    BlockDriver *drv;
  37    BlockdevCreateOptions *opts;
  38} BlockdevCreateJob;
  39
  40static int coroutine_fn blockdev_create_run(Job *job, Error **errp)
  41{
  42    BlockdevCreateJob *s = container_of(job, BlockdevCreateJob, common);
  43    int ret;
  44
  45    GLOBAL_STATE_CODE();
  46    GRAPH_RDLOCK_GUARD();
  47
  48    job_progress_set_remaining(&s->common, 1);
  49    ret = s->drv->bdrv_co_create(s->opts, errp);
  50    job_progress_update(&s->common, 1);
  51
  52    qapi_free_BlockdevCreateOptions(s->opts);
  53
  54    return ret;
  55}
  56
  57static const JobDriver blockdev_create_job_driver = {
  58    .instance_size = sizeof(BlockdevCreateJob),
  59    .job_type      = JOB_TYPE_CREATE,
  60    .run           = blockdev_create_run,
  61};
  62
  63/* Checking whether the function is present doesn't require the graph lock */
  64static inline bool TSA_NO_TSA has_bdrv_co_create(BlockDriver *drv)
  65{
  66    return drv->bdrv_co_create;
  67}
  68
  69void qmp_blockdev_create(const char *job_id, BlockdevCreateOptions *options,
  70                         Error **errp)
  71{
  72    BlockdevCreateJob *s;
  73    const char *fmt = BlockdevDriver_str(options->driver);
  74    BlockDriver *drv = bdrv_find_format(fmt);
  75
  76    if (!drv) {
  77        error_setg(errp, "Block driver '%s' not found or not supported", fmt);
  78        return;
  79    }
  80
  81    /* If the driver is in the schema, we know that it exists. But it may not
  82     * be whitelisted. */
  83    if (bdrv_uses_whitelist() && !bdrv_is_whitelisted(drv, false)) {
  84        error_setg(errp, "Driver is not whitelisted");
  85        return;
  86    }
  87
  88    /* Error out if the driver doesn't support .bdrv_co_create */
  89    if (!has_bdrv_co_create(drv)) {
  90        error_setg(errp, "Driver does not support blockdev-create");
  91        return;
  92    }
  93
  94    /* Create the block job */
  95    /* TODO Running in the main context. Block drivers need to error out or add
  96     * locking when they use a BDS in a different AioContext. */
  97    s = job_create(job_id, &blockdev_create_job_driver, NULL,
  98                   qemu_get_aio_context(), JOB_DEFAULT | JOB_MANUAL_DISMISS,
  99                   NULL, NULL, errp);
 100    if (!s) {
 101        return;
 102    }
 103
 104    s->drv = drv,
 105    s->opts = QAPI_CLONE(BlockdevCreateOptions, options),
 106
 107    job_start(&s->common);
 108}
 109