Re: [Qemu-devel] [PATCH 16/16] Make qemu-io commands available in the monitor

[Eric Blake]

On 05/28/2013 09:27 AM, Kevin Wolf wrote:
> The QMP version is flagged with a __org.qemu.debug- prefix in order to
> reinforce the statement that qemu-io is for testing and debugging only,
> with no API guarantees.

Correct use of naming conventions.

Hmm, I wonder if the recent addition of an 'abort' action to
'transaction' should be renamed __org.qemu.debug-abort, to make it
obvious that it is another case of a QMP command useful mainly for
testing, and not real-life use.

> 
> The HMP version is simply called 'qemu-io' for convenience.
> 
> Signed-off-by: Kevin Wolf <address@hidden>
> ---

> +++ b/hmp-commands.hx
> @@ -1551,6 +1551,22 @@ Removes the chardev @var{id}.
>  ETEXI
>  
>      {
> +        .name       = "qemu-io",
> +        .args_type  = "device:B,command:s",
> +        .params     = "[device] \"[command]\"",
> +        .help       = "run a qemu-io command on a block device",
> +        .mhandler.cmd = hmp_qemu_io,
> +    },
> +
> +STEXI
> address@hidden chardev_remove id
> address@hidden chardev_remove
> +
> +Removes the chardev @var{id}.

Is this the right documentation?

> +++ b/qapi-schema.json
> @@ -3618,3 +3618,19 @@
>              '*cpuid-input-ecx': 'int',
>              'cpuid-register': 'X86CPURegister32',
>              'features': 'int' } }
> +
> +##
> +# @__org.qemu.debug-qemu-io-command
> +#
> +# Execute a qemu-io command
> +#
> +# @device:  The block device on which the command should be executed
> +#
> +# @command: The command to execute
> +#
> +# Returns:  Nothing on success
> +#
> +# Since: 1.6 (testing and debugging use only, no API stability)
> +##
> +{ 'command': '__org.qemu.debug-qemu-io-command',
> +  'data': {'device': 'str', 'command': 'str'} }

I would have asked that 'command' be an enum, except that we promise no
API stability so there's no need to lock us into an enum that could be
introspected :)  This command looks fine as-is.

> diff --git a/qmp-commands.hx b/qmp-commands.hx
> index ffd130e..8682bea 100644
> --- a/qmp-commands.hx
> +++ b/qmp-commands.hx
> @@ -2932,3 +2932,31 @@ Example:
>  <- { "return": {} }
>  
>  EQMP
> +
> +    {
> +        .name       = "__org.qemu.debug-qemu-io-command",
> +        .args_type  = "device:s,command:s",
> +        .mhandler.cmd_new = 
> qmp_marshal_input___org_qemu_debug_qemu_io_command,
> +    },
> +
> +
> +SQMP
> +__org.qemu.debug-qemu-io-command
> +--------------------------------

Do we really need to have SQMP documentation of the command, or is
listing of its handler sufficient?  In other words, if this is
debug-only, can we just leave it undocumented instead of listing an
example only to declare the example non-portable?

-- 
Eric Blake   eblake redhat com    +1-919-301-3266
Libvirt virtualization library http://libvirt.org

signature.asc
Description: OpenPGP digital signature