Subject: bug#8001: cp (8.10) sparse handling fails on compressed btrfs (cp/fiemap-2)

From: Pádraig Brady <[email-masked]>
Date: Sat, 19 Feb 2011 23:22:15 +0000

On 19/02/11 18:28, Mike Frysinger wrote:
> based on other threads (which i havent been following too closely), did we 
> settle on this being a btrfs bug ?
> -mike

Nope, cp 8.10 is not absolved yet.
It may be btrfs not honoring FIEMAP_FLAG_SYNC,
and/or it may be cp needing to handle FIEMAP_EXTENT_ENCODED
specially.

It would help if you ran `sync` before the copy,
to exclude that as a possible issue.

Also `filefrag -v` output for the file on
the compressed BTRFS file system would be helpful.

thanks,
Pádraig.