This changes the x-blockdev-create QMP command so that it doesn't block
the monitor and the main loop any more, but starts a background job that
performs the image creation.
The basic job as implemented here is all that is necessary to make image
creation asynchronous and to provide a QMP interface that can be marked
stable, but it still lacks a few features that jobs usually provide: The
job will ignore pause commands and it doesn't publish more than very
basic progress yet (total-progress is 1 and current-progress advances
from 0 to 1 when the driver callbacks returns). These features can be
added later without breaking compatibility.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
---
qapi/block-core.json | 14 ++++++----
qapi/job.json | 4 ++-
block/create.c | 67 +++++++++++++++++++++++++++++++++---------------
tests/qemu-iotests/group | 14 +++++-----
4 files changed, 66 insertions(+), 33 deletions(-)
diff --git a/qapi/block-core.json b/qapi/block-core.json
index ad66ad6f80..eb98596614 100644
--- a/qapi/block-core.json
+++ b/qapi/block-core.json
@@ -4013,14 +4013,18 @@
##
# @x-blockdev-create:
#
-# Create an image format on a given node.
-# TODO Replace with something asynchronous (block job?)
+# Starts a job to create an image format on a given node. The job is
+# automatically finalized, but a manual job-dismiss is required.
#
-# Since: 2.12
+# @job-id: Identifier for the newly created job.
+#
+# @options: Options for the image creation.
+#
+# Since: 3.0
##
{ 'command': 'x-blockdev-create',
- 'data': 'BlockdevCreateOptions',
- 'boxed': true }
+ 'data': { 'job-id': 'str',
+ 'options': 'BlockdevCreateOptions' } }
##
# @blockdev-open-tray:
diff --git a/qapi/job.json b/qapi/job.json
index 970124de76..69c1970a58 100644
--- a/qapi/job.json
+++ b/qapi/job.json
@@ -17,10 +17,12 @@
#
# @backup: drive backup job type, see "drive-backup"
#
+# @create: image creation job type, see "x-blockdev-create" (since 3.0)
+#
# Since: 1.7
##
{ 'enum': 'JobType',
- 'data': ['commit', 'stream', 'mirror', 'backup'] }
+ 'data': ['commit', 'stream', 'mirror', 'backup', 'create'] }
##
# @JobStatus:
diff --git a/block/create.c b/block/create.c
index 8bd8a03719..1a263e4b13 100644
--- a/block/create.c
+++ b/block/create.c
@@ -24,28 +24,51 @@
#include "qemu/osdep.h"
#include "block/block_int.h"
+#include "qemu/job.h"
#include "qapi/qapi-commands-block-core.h"
+#include "qapi/qapi-visit-block-core.h"
+#include "qapi/clone-visitor.h"
#include "qapi/error.h"
-typedef struct BlockdevCreateCo {
+typedef struct BlockdevCreateJob {
+ Job common;
BlockDriver *drv;
BlockdevCreateOptions *opts;
int ret;
- Error **errp;
-} BlockdevCreateCo;
+ Error *err;
+} BlockdevCreateJob;
-static void coroutine_fn bdrv_co_create_co_entry(void *opaque)
+static void blockdev_create_complete(Job *job, void *opaque)
{
- BlockdevCreateCo *cco = opaque;
- cco->ret = cco->drv->bdrv_co_create(cco->opts, cco->errp);
+ BlockdevCreateJob *s = container_of(job, BlockdevCreateJob, common);
+
+ job_completed(job, s->ret, s->err);
}
-void qmp_x_blockdev_create(BlockdevCreateOptions *options, Error **errp)
+static void coroutine_fn blockdev_create_run(void *opaque)
{
+ BlockdevCreateJob *s = opaque;
+
+ job_progress_set_remaining(&s->common, 1);
+ s->ret = s->drv->bdrv_co_create(s->opts, &s->err);
+ job_progress_update(&s->common, 1);
+
+ qapi_free_BlockdevCreateOptions(s->opts);
+ job_defer_to_main_loop(&s->common, blockdev_create_complete, NULL);
+}
+
+static const JobDriver blockdev_create_job_driver = {
+ .instance_size = sizeof(BlockdevCreateJob),
+ .job_type = JOB_TYPE_CREATE,
+ .start = blockdev_create_run,
+};
+
+void qmp_x_blockdev_create(const char *job_id, BlockdevCreateOptions *options,
+ Error **errp)
+{
+ BlockdevCreateJob *s;
const char *fmt = BlockdevDriver_str(options->driver);
BlockDriver *drv = bdrv_find_format(fmt);
- Coroutine *co;
- BlockdevCreateCo cco;
/* If the driver is in the schema, we know that it exists. But it may not
* be whitelisted. */
@@ -55,22 +78,24 @@ void qmp_x_blockdev_create(BlockdevCreateOptions *options, Error **errp)
return;
}
- /* Call callback if it exists */
+ /* Error out if the driver doesn't support .bdrv_co_create */
if (!drv->bdrv_co_create) {
error_setg(errp, "Driver does not support blockdev-create");
return;
}
- cco = (BlockdevCreateCo) {
- .drv = drv,
- .opts = options,
- .ret = -EINPROGRESS,
- .errp = errp,
- };
-
- co = qemu_coroutine_create(bdrv_co_create_co_entry, &cco);
- qemu_coroutine_enter(co);
- while (cco.ret == -EINPROGRESS) {
- aio_poll(qemu_get_aio_context(), true);
+ /* Create the block job */
+ /* TODO Running in the main context. Block drivers need to error out or add
+ * locking when they use a BDS in a different AioContext. */
+ s = job_create(job_id, &blockdev_create_job_driver, NULL,
+ qemu_get_aio_context(), JOB_DEFAULT | JOB_MANUAL_DISMISS,
+ NULL, NULL, errp);
+ if (!s) {
+ return;
}
+
+ s->drv = drv,
+ s->opts = QAPI_CLONE(BlockdevCreateOptions, options),
+
+ job_start(&s->common);
}
diff --git a/tests/qemu-iotests/group b/tests/qemu-iotests/group
index 93f93d71ba..22b0082db3 100644
--- a/tests/qemu-iotests/group
+++ b/tests/qemu-iotests/group
@@ -204,14 +204,16 @@
203 rw auto migration
204 rw auto quick
205 rw auto quick
-206 rw auto
-207 rw auto
+# TODO The following commented out tests need to be reworked to work
+# with the x-blockdev-create job
+#206 rw auto
+#207 rw auto
208 rw auto quick
209 rw auto quick
-210 rw auto
-211 rw auto quick
-212 rw auto quick
-213 rw auto quick
+#210 rw auto
+#211 rw auto quick
+#212 rw auto quick
+#213 rw auto quick
214 rw auto
215 rw auto quick
216 rw auto quick
--
2.13.6
On Tue, May 29, 2018 at 10:38:58PM +0200, Kevin Wolf wrote:
> This changes the x-blockdev-create QMP command so that it doesn't block
> the monitor and the main loop any more, but starts a background job that
> performs the image creation.
>
> The basic job as implemented here is all that is necessary to make image
> creation asynchronous and to provide a QMP interface that can be marked
> stable, but it still lacks a few features that jobs usually provide: The
> job will ignore pause commands and it doesn't publish more than very
> basic progress yet (total-progress is 1 and current-progress advances
> from 0 to 1 when the driver callbacks returns). These features can be
> added later without breaking compatibility.
>
> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
> Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
> ---
> qapi/block-core.json | 14 ++++++----
> qapi/job.json | 4 ++-
> block/create.c | 67 +++++++++++++++++++++++++++++++++---------------
> tests/qemu-iotests/group | 14 +++++-----
> 4 files changed, 66 insertions(+), 33 deletions(-)
>
> diff --git a/qapi/block-core.json b/qapi/block-core.json
> index ad66ad6f80..eb98596614 100644
> --- a/qapi/block-core.json
> +++ b/qapi/block-core.json
> @@ -4013,14 +4013,18 @@
> ##
> # @x-blockdev-create:
> #
> -# Create an image format on a given node.
> -# TODO Replace with something asynchronous (block job?)
> +# Starts a job to create an image format on a given node. The job is
> +# automatically finalized, but a manual job-dismiss is required.
> #
> -# Since: 2.12
> +# @job-id: Identifier for the newly created job.
> +#
> +# @options: Options for the image creation.
> +#
> +# Since: 3.0
> ##
> { 'command': 'x-blockdev-create',
> - 'data': 'BlockdevCreateOptions',
> - 'boxed': true }
> + 'data': { 'job-id': 'str',
> + 'options': 'BlockdevCreateOptions' } }
>
> ##
> # @blockdev-open-tray:
> diff --git a/qapi/job.json b/qapi/job.json
> index 970124de76..69c1970a58 100644
> --- a/qapi/job.json
> +++ b/qapi/job.json
> @@ -17,10 +17,12 @@
> #
> # @backup: drive backup job type, see "drive-backup"
> #
> +# @create: image creation job type, see "x-blockdev-create" (since 3.0)
> +#
> # Since: 1.7
> ##
> { 'enum': 'JobType',
> - 'data': ['commit', 'stream', 'mirror', 'backup'] }
> + 'data': ['commit', 'stream', 'mirror', 'backup', 'create'] }
>
> ##
> # @JobStatus:
> diff --git a/block/create.c b/block/create.c
> index 8bd8a03719..1a263e4b13 100644
> --- a/block/create.c
> +++ b/block/create.c
> @@ -24,28 +24,51 @@
>
> #include "qemu/osdep.h"
> #include "block/block_int.h"
> +#include "qemu/job.h"
> #include "qapi/qapi-commands-block-core.h"
> +#include "qapi/qapi-visit-block-core.h"
> +#include "qapi/clone-visitor.h"
> #include "qapi/error.h"
>
> -typedef struct BlockdevCreateCo {
> +typedef struct BlockdevCreateJob {
> + Job common;
> BlockDriver *drv;
> BlockdevCreateOptions *opts;
> int ret;
> - Error **errp;
> -} BlockdevCreateCo;
> + Error *err;
> +} BlockdevCreateJob;
>
> -static void coroutine_fn bdrv_co_create_co_entry(void *opaque)
> +static void blockdev_create_complete(Job *job, void *opaque)
> {
> - BlockdevCreateCo *cco = opaque;
> - cco->ret = cco->drv->bdrv_co_create(cco->opts, cco->errp);
> + BlockdevCreateJob *s = container_of(job, BlockdevCreateJob, common);
> +
> + job_completed(job, s->ret, s->err);
> }
>
> -void qmp_x_blockdev_create(BlockdevCreateOptions *options, Error **errp)
> +static void coroutine_fn blockdev_create_run(void *opaque)
> {
> + BlockdevCreateJob *s = opaque;
> +
> + job_progress_set_remaining(&s->common, 1);
> + s->ret = s->drv->bdrv_co_create(s->opts, &s->err);
> + job_progress_update(&s->common, 1);
> +
> + qapi_free_BlockdevCreateOptions(s->opts);
> + job_defer_to_main_loop(&s->common, blockdev_create_complete, NULL);
> +}
> +
> +static const JobDriver blockdev_create_job_driver = {
> + .instance_size = sizeof(BlockdevCreateJob),
> + .job_type = JOB_TYPE_CREATE,
> + .start = blockdev_create_run,
> +};
> +
> +void qmp_x_blockdev_create(const char *job_id, BlockdevCreateOptions *options,
> + Error **errp)
> +{
> + BlockdevCreateJob *s;
> const char *fmt = BlockdevDriver_str(options->driver);
> BlockDriver *drv = bdrv_find_format(fmt);
> - Coroutine *co;
> - BlockdevCreateCo cco;
>
> /* If the driver is in the schema, we know that it exists. But it may not
> * be whitelisted. */
> @@ -55,22 +78,24 @@ void qmp_x_blockdev_create(BlockdevCreateOptions *options, Error **errp)
> return;
> }
>
> - /* Call callback if it exists */
> + /* Error out if the driver doesn't support .bdrv_co_create */
> if (!drv->bdrv_co_create) {
> error_setg(errp, "Driver does not support blockdev-create");
> return;
> }
>
> - cco = (BlockdevCreateCo) {
> - .drv = drv,
> - .opts = options,
> - .ret = -EINPROGRESS,
> - .errp = errp,
> - };
> -
> - co = qemu_coroutine_create(bdrv_co_create_co_entry, &cco);
> - qemu_coroutine_enter(co);
> - while (cco.ret == -EINPROGRESS) {
> - aio_poll(qemu_get_aio_context(), true);
> + /* Create the block job */
> + /* TODO Running in the main context. Block drivers need to error out or add
> + * locking when they use a BDS in a different AioContext. */
> + s = job_create(job_id, &blockdev_create_job_driver, NULL,
> + qemu_get_aio_context(), JOB_DEFAULT | JOB_MANUAL_DISMISS,
> + NULL, NULL, errp);
> + if (!s) {
> + return;
> }
> +
> + s->drv = drv,
> + s->opts = QAPI_CLONE(BlockdevCreateOptions, options),
> +
> + job_start(&s->common);
> }
> diff --git a/tests/qemu-iotests/group b/tests/qemu-iotests/group
> index 93f93d71ba..22b0082db3 100644
> --- a/tests/qemu-iotests/group
> +++ b/tests/qemu-iotests/group
> @@ -204,14 +204,16 @@
> 203 rw auto migration
> 204 rw auto quick
> 205 rw auto quick
> -206 rw auto
> -207 rw auto
> +# TODO The following commented out tests need to be reworked to work
> +# with the x-blockdev-create job
> +#206 rw auto
> +#207 rw auto
> 208 rw auto quick
> 209 rw auto quick
> -210 rw auto
> -211 rw auto quick
> -212 rw auto quick
> -213 rw auto quick
> +#210 rw auto
> +#211 rw auto quick
> +#212 rw auto quick
> +#213 rw auto quick
> 214 rw auto
> 215 rw auto quick
> 216 rw auto quick
> --
> 2.13.6
>
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