Re: [Qemu-devel] [PATCH v7 32/39] blockdev: Implement eject with basic operations

[Kevin Wolf]

Am 19.10.2015 um 17:53 hat Max Reitz geschrieben:
> Implement 'eject' by calling blockdev-open-tray and
> blockdev-remove-medium.
> 
> Signed-off-by: Max Reitz <address@hidden>
> ---
>  blockdev.c | 11 +++++------
>  1 file changed, 5 insertions(+), 6 deletions(-)
> 
> diff --git a/blockdev.c b/blockdev.c
> index a4c278f..0481686 100644
> --- a/blockdev.c
> +++ b/blockdev.c
> @@ -1941,16 +1941,15 @@ out:
>  
>  void qmp_eject(const char *device, bool has_force, bool force, Error **errp)
>  {
> -    BlockBackend *blk;
> +    Error *local_err = NULL;
>  
> -    blk = blk_by_name(device);
> -    if (!blk) {
> -        error_set(errp, ERROR_CLASS_DEVICE_NOT_FOUND,
> -                  "Device '%s' not found", device);
> +    qmp_blockdev_open_tray(device, has_force, force, &local_err);
> +    if (local_err) {
> +        error_propagate(errp, local_err);
>          return;
>      }

This changes the behaviour, in the current patch series in two ways if
the device is locked:

1. With force, the qmp_blockdev_remove_medium() call will fail because
   we only unlocked the device, but didn't actually open the tray (I
   commented on this in the qmp_blockdev_open_tray() patch). This breaks
   the API, obviously.

2. Without force, eject previously sent an eject request and also
   returned a "Device is locked" error. Now it fails with "Tray of
   device is not open". Regression in the message quality, but not an
   API breakage because tools must not parse the message.

> -    eject_device(blk, force, errp);
> +    qmp_blockdev_remove_medium(device, errp);
>  }

Kevin