Re: [Qemu-devel] [PATCH v2 14/36] block: x-blockdev-create QMP command

2018-02-22 Thread Eric Blake 

On 02/21/2018 07:53 AM, Kevin Wolf wrote:

This adds a synchronous x-blockdev-create QMP command that can create
qcow2 images on a given node name.

We don't want to block while creating an image, so this is not the final
interface in all aspects, but BlockdevCreateOptionsQcow2 and
.bdrv_co_create() are what they actually might look like in the end. In
any case, this should be good enough to test whether we interpret
BlockdevCreateOptions as we should.

Signed-off-by: Kevin Wolf 
---
  qapi/block-core.json  | 12 
  include/block/block_int.h |  2 ++
  block/create.c| 76 +++
  block/qcow2.c |  3 +-
  block/Makefile.objs   |  2 +-
  5 files changed, 93 insertions(+), 2 deletions(-)
  create mode 100644 block/create.c



Reviewed-by: Eric Blake 

--
Eric Blake, Principal Software Engineer
Red Hat, Inc.   +1-919-301-3266
Virtualization:  qemu.org | libvirt.org

Re: [Qemu-devel] [PATCH v2 14/36] block: x-blockdev-create QMP command

2018-02-22 Thread Max Reitz 
On 2018-02-21 14:53, Kevin Wolf wrote:
> This adds a synchronous x-blockdev-create QMP command that can create
> qcow2 images on a given node name.
> 
> We don't want to block while creating an image, so this is not the final
> interface in all aspects, but BlockdevCreateOptionsQcow2 and
> .bdrv_co_create() are what they actually might look like in the end. In
> any case, this should be good enough to test whether we interpret
> BlockdevCreateOptions as we should.
> 
> Signed-off-by: Kevin Wolf 
> ---
>  qapi/block-core.json  | 12 
>  include/block/block_int.h |  2 ++
>  block/create.c| 76 
> +++
>  block/qcow2.c |  3 +-
>  block/Makefile.objs   |  2 +-
>  5 files changed, 93 insertions(+), 2 deletions(-)
>  create mode 100644 block/create.c

Reviewed-by: Max Reitz 



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[Qemu-devel] [PATCH v2 14/36] block: x-blockdev-create QMP command

2018-02-21 Thread Kevin Wolf 
This adds a synchronous x-blockdev-create QMP command that can create
qcow2 images on a given node name.

We don't want to block while creating an image, so this is not the final
interface in all aspects, but BlockdevCreateOptionsQcow2 and
.bdrv_co_create() are what they actually might look like in the end. In
any case, this should be good enough to test whether we interpret
BlockdevCreateOptions as we should.

Signed-off-by: Kevin Wolf 
---
 qapi/block-core.json  | 12 
 include/block/block_int.h |  2 ++
 block/create.c| 76 +++
 block/qcow2.c |  3 +-
 block/Makefile.objs   |  2 +-
 5 files changed, 93 insertions(+), 2 deletions(-)
 create mode 100644 block/create.c

diff --git a/qapi/block-core.json b/qapi/block-core.json
index 74b864d64e..359195a1a3 100644
--- a/qapi/block-core.json
+++ b/qapi/block-core.json
@@ -3464,6 +3464,18 @@
   } }
 
 ##
+# @x-blockdev-create:
+#
+# Create an image format on a given node.
+# TODO Replace with something asynchronous (block job?)
+#
+# Since: 2.12
+##
+{ 'command': 'x-blockdev-create',
+  'data': 'BlockdevCreateOptions',
+  'boxed': true }
+
+##
 # @blockdev-open-tray:
 #
 # Opens a block device's tray. If there is a block driver state tree inserted 
as
diff --git a/include/block/block_int.h b/include/block/block_int.h
index 5ae7738cf8..0b43fae782 100644
--- a/include/block/block_int.h
+++ b/include/block/block_int.h
@@ -128,6 +128,8 @@ struct BlockDriver {
 int (*bdrv_file_open)(BlockDriverState *bs, QDict *options, int flags,
   Error **errp);
 void (*bdrv_close)(BlockDriverState *bs);
+int coroutine_fn (*bdrv_co_create)(BlockdevCreateOptions *opts,
+   Error **errp);
 int (*bdrv_create)(const char *filename, QemuOpts *opts, Error **errp);
 int (*bdrv_make_empty)(BlockDriverState *bs);
 
diff --git a/block/create.c b/block/create.c
new file mode 100644
index 00..dfd31eca37
--- /dev/null
+++ b/block/create.c
@@ -0,0 +1,76 @@
+/*
+ * Block layer code related to image creation
+ *
+ * Copyright (c) 2018 Kevin Wolf 
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to 
deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING 
FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include "qemu/osdep.h"
+#include "block/block_int.h"
+#include "qmp-commands.h"
+#include "qapi/error.h"
+
+typedef struct BlockdevCreateCo {
+BlockDriver *drv;
+BlockdevCreateOptions *opts;
+int ret;
+Error **errp;
+} BlockdevCreateCo;
+
+static void coroutine_fn bdrv_co_create_co_entry(void *opaque)
+{
+BlockdevCreateCo *cco = opaque;
+cco->ret = cco->drv->bdrv_co_create(cco->opts, cco->errp);
+}
+
+void qmp_x_blockdev_create(BlockdevCreateOptions *options, Error **errp)
+{
+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. */
+assert(drv);
+if (bdrv_uses_whitelist() && !bdrv_is_whitelisted(drv, false)) {
+error_setg(errp, "Driver is not whitelisted");
+return;
+}
+
+/* Call callback if it exists */
+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, );
+qemu_coroutine_enter(co);
+while (cco.ret == -EINPROGRESS) {
+aio_poll(qemu_get_aio_context(), true);
+}
+}
diff --git a/block/qcow2.c b/block/qcow2.c
index 58737d0833..8acb36b0af 100644
--- a/block/qcow2.c
+++ b/block/qcow2.c
@@ -4463,7 +4463,8 @@ BlockDriver bdrv_qcow2 = {
 .bdrv_reopen_abort= qcow2_reopen_abort,
 .bdrv_join_options=