Re: [Qemu-devel] [PATCH 2/2] fdc: fix media detection

[Pavel Hrdina <phrdina@redhat.com>]

On 05/22/2012 02:01 PM, Kevin Wolf wrote:
> Am 22.05.2012 12:59, schrieb Pavel Hrdina:
>> We have to set up 'media_changed' after guest start so floppy driver
>> could detect that there is no media in drive. For this purpose we call
>> 'fdctrl_change_cb' instead of 'fd_revalidate' in 'fdctrl_connect_drives'.
>> 'fd_revalidate' is called inside 'fdctrl_change_cb'.
>>
>> In 'fdctrl_handle_seek' we always set current track because we don't care
>> if there is media inserted or not.
>>
>> Signed-off-by: Pavel Hrdina<phrdina@redhat.com>
> Can you please add a qtest case that shows the problems that you're
> fixing in this series?
I'm new to qemu. By "add a qtest case" you mean update tests/fdc-test.c ?
>> diff --git a/hw/fdc.c b/hw/fdc.c
>> index cb4cd25..337b35a 100644
>> --- a/hw/fdc.c
>> +++ b/hw/fdc.c
>> @@ -1617,11 +1617,7 @@ static void fdctrl_handle_seek(FDCtrl *fdctrl, int direction)
>>       /* The seek command just sends step pulses to the drive and doesn't care if
>>        * there is a medium inserted of if it's banging the head against the drive.
>>        */
>> -    if (fdctrl->fifo[2]>  cur_drv->max_track) {
>> -        cur_drv->track = cur_drv->max_track;
>> -    } else {
>> -        cur_drv->track = fdctrl->fifo[2];
>> -    }
>> +    cur_drv->track = fdctrl->fifo[2];
> Why is it okay to have cur_drv->track point outside the floppy? Won't it
> mess up future calculations? Not all other places check it again
> cur_drv->max_track.
>
> Kevin
Well, you are right. Than we have to set 'max_track' even if there is no 
media. I tested this on bare-metal without media and where floppy driver 
ask to seek to specific track, it ends good and return specific track 
position as actual.
I'll rewrite this behavior and send patch v2.