On 13.02.2017 18:22, Kevin Wolf wrote:
> This function allows to create more or less normal BlockDriverStates
> even for BlockDrivers that aren't globally registered (e.g. helper
> filters for block jobs).
>
> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
> ---
> block.c | 31 ++++++++++++++++++++++++++++++-
> include/block/block.h | 2 ++
> 2 files changed, 32 insertions(+), 1 deletion(-)
>
> diff --git a/block.c b/block.c
> index 9c80cba..7d84d43 100644
> --- a/block.c
> +++ b/block.c
> @@ -948,13 +948,16 @@ static int bdrv_open_driver(BlockDriverState *bs, BlockDriver *drv,
> }
>
> bs->drv = drv;
> + bs->read_only = !(bs->open_flags & BDRV_O_RDWR);
> bs->opaque = g_malloc0(drv->instance_size);
>
> if (drv->bdrv_file_open) {
> assert(!drv->bdrv_needs_filename || bs->filename[0]);
> ret = drv->bdrv_file_open(bs, options, open_flags, &local_err);
> - } else {
> + } else if (drv->bdrv_open) {
> ret = drv->bdrv_open(bs, options, open_flags, &local_err);
> + } else {
> + ret = 0;
> }
>
> if (ret < 0) {
> @@ -995,6 +998,32 @@ free_and_fail:
> return ret;
> }
>
> +int bdrv_new_open_driver(BlockDriver *drv, BlockDriverState **result,
Really? After we put much work into getting bdrv_open() to return a BDS
pointer? :-/
Do you need to distinguish based on -EPERM somewhere? I'd much rather
have the BDS pointer returned, personally. If you need the integer
return value somewhere, couldn't that be a parameter (which can
optionally be NULL if the caller doesn't need it)?
Max
> + const char *node_name, int flags, Error **errp)
> +{
> + BlockDriverState *bs;
> + int ret;
> +
> + bs = bdrv_new();
> + bs->open_flags = flags;
> + bs->explicit_options = qdict_new();
> + bs->options = qdict_new();
> + bs->opaque = NULL;
> +
> + update_options_from_flags(bs->options, flags);
> +
> + ret = bdrv_open_driver(bs, drv, node_name, bs->options, flags, errp);
> + if (ret < 0) {
> + QDECREF(bs->explicit_options);
> + QDECREF(bs->options);
> + bdrv_unref(bs);
> + return ret;
> + }
> +
> + *result = bs;
> + return 0;
> +}
> +
> QemuOptsList bdrv_runtime_opts = {
> .name = "bdrv_common",
> .head = QTAILQ_HEAD_INITIALIZER(bdrv_runtime_opts.head),
> diff --git a/include/block/block.h b/include/block/block.h
> index 93812df..3238850 100644
> --- a/include/block/block.h
> +++ b/include/block/block.h
> @@ -215,6 +215,8 @@ int bdrv_open_backing_file(BlockDriverState *bs, QDict *parent_options,
> const char *bdref_key, Error **errp);
> BlockDriverState *bdrv_open(const char *filename, const char *reference,
> QDict *options, int flags, Error **errp);
> +int bdrv_new_open_driver(BlockDriver *drv, BlockDriverState **result,
> + const char *node_name, int flags, Error **errp);
> BlockReopenQueue *bdrv_reopen_queue(BlockReopenQueue *bs_queue,
> BlockDriverState *bs,
> QDict *options, int flags);
>