Re: Can I see what device was used to mount btrfs?

[Adam Borowski <kilobyte@angband.pl>]

On Tue, May 02, 2017 at 10:15:06PM +0200, Kai Krakow wrote:
> Ideally, the btrfs wouldn't even appear in /dev until it was assembled
> by udev. But apparently that's not the case, and I think this is where
> the problems come from. I wish, btrfs would not show up as device nodes
> in /dev that the mount command identified as btrfs. Instead, btrfs
> would expose (probably through udev) a device node
> in /dev/btrfs/fs_identifier when it is ready.
> 
> Apparently, the core problem of how to handle degraded btrfs still
> remains. Maybe it could be solved by adding more stages of btrfs nodes,
> like /dev/btrfs-incomplete (for unusable btrfs), /dev/btrfs-degraded
> (for btrfs still missing devices but at least one stripe of btrfs raid
> available) and /dev/btrfs as the final stage.

The problem is, we can't tell these states apart other than doing the vast
majority of mount's work.  As I described earlier in this thread, even the
"fully available" stage is not trivial.


Meow!
-- 
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solely on their merits.  Heck, even if occasionally a cider applies for a
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