Am 12.12.2013 um 16:33 hat Benoît Canet geschrieben:
> There was two candidate ways to implement named node manipulation:
>
> 1)
> { 'command': 'block_passwd', 'data': {'*device': 'str',
> '*node-name': 'str', 'password': 'str'}
> }
>
> 2)
>
> { 'command': 'block_passwd', 'data': {'device': 'str',
> '*device-is-node': 'bool',
> 'password': 'str'} }
>
> Luiz proposed 1 and says 2 was an abuse of the QMP interface and proposed to
> rewrite the QMP block interface for 2.0.
>
> Luiz does not like in 1 the fact that 2 fields are optional but one of them
> must
> be specified leading to an abuse of the QMP semantic.
>
> Kevin argumented that 2 what a clear abuse of the device field and would not
> be
> practical when reading fast some log file because the user would read "device"
> and think that a device is manipulated when it's in fact a node name.
> Documentation of 1 make it pretty clear what to do for the user.
>
> Kevin argued that all bs are node including devices ones so 2 does not make
> sense.
>
> Kevin also argued that rewriting the QMP block interface would not make
> disapear
> the current one.
>
> Kevin pushed the argument that making the QAPI generator compatible with the
> semantic of the operation would need a rewrite that no one has done yet.
>
> A vote has been done on the list to elect the version to use and 1 won.
>
> For reference the complete thread is:
> "[Qemu-devel] [PATCH V4 4/7] qmp: Allow to change password on names block
> driver
> states."
>
> Signed-off-by: Benoit Canet <ben...@irqsave.net>
> ---
> block.c | 32 ++++++++++++++++++++++++++++++++
> blockdev.c | 13 +++++++++----
> hmp.c | 2 +-
> include/block/block.h | 3 +++
> qapi-schema.json | 9 +++++++--
> qmp-commands.hx | 3 ++-
> 6 files changed, 54 insertions(+), 8 deletions(-)
>
> diff --git a/block.c b/block.c
> index 78d13e5..22190a4 100644
> --- a/block.c
> +++ b/block.c
> @@ -3207,6 +3207,38 @@ BlockDeviceInfoList *bdrv_named_nodes_list(void)
> return list;
> }
>
> +BlockDriverState *bdrv_lookup_bs(bool has_device, const char *device,
> + bool has_node_name, const char *node_name,
> + Error **errp)
This is a normal function without generated callers, so can we get rid
of has_device/has_node_name and just switch to passing NULL if it's not
present? That would make it more convenient to use this function in
other places.
Kevin
