Re: [PATCH 16/19] ataflop: use a separate gendisk for each media format

[Hannes Reinecke]

On 9/3/20 10:01 AM, Christoph Hellwig wrote:
> The Atari floppy driver usually autodetects the media when used with the
> ormal /dev/fd? devices, which also are the only nodes created by udev.
> But it also supports various aliases that force a given media format.
> That is currently supported using the blk_register_region framework
> which finds the floppy gendisk even for a 'mismatched' dev_t.  The
> problem with this (besides the code complexity) is that it creates
> multiple struct block_device instances for the whole device of a
> single gendisk, which can lead to interesting issues in code not
> aware of that fact.
>
> To fix this just create a separate gendisk for each of the aliases
> if they are accessed.
>
> Signed-off-by: Christoph Hellwig <hch@xxxxxx>
> ---
>   drivers/block/ataflop.c | 135 +++++++++++++++++++++++++---------------
>   1 file changed, 86 insertions(+), 49 deletions(-)
Reviewed-by: Hannes Reinecke <hare@xxxxxxx>

Cheers,

Hannes
--
Dr. Hannes Reinecke                Kernel Storage Architect
hare@xxxxxxx                              +49 911 74053 688
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