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Date:   Tue, 7 Dec 2021 19:56:11 +0100
From:   David Sterba <dsterba@suse.cz>
To:     Anand Jain <anand.jain@oracle.com>
Cc:     linux-btrfs@vger.kernel.org, Josef Bacik <josef@toxicpanda.com>
Subject: Re: [PATCH v2 2/2] btrfs: sysfs add devinfo/fsid to retrieve fsid
 from the device
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        linux-btrfs@vger.kernel.org, Josef Bacik <josef@toxicpanda.com>
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On Thu, Oct 21, 2021 at 11:31:17PM +0800, Anand Jain wrote:
> In the case of the seed device, the fsid can be different from the mounted
> sprout fsid.  The userland has to read the device superblock to know the
> fsid but, that idea fails if the device is missing. So add a sysfs
> interface devinfo/<devid>/fsid to show the fsid of the device.
> 
> For example:
>  $ cd /sys/fs/btrfs/b10b02a5-f9de-4276-b9e8-2bfd09a578a8
> 
>  $ cat devinfo/1/fsid
>  c44d771f-639d-4df3-99ec-5bc7ad2af93b
>  $ cat  devinfo/3/fsid
>  b10b02a5-f9de-4276-b9e8-2bfd09a578a8
> 
> Signed-off-by: Anand Jain <anand.jain@oracle.com>
> Reviewed-by: Josef Bacik <josef@toxicpanda.com>

Added to misc-next, thanks.