btrfs: update comment for BTRFS_RESERVE_NO_FLUSH

The comment is incomplete as BTRFS_RESERVE_NO_FLUSH is used for more
reasons than currently holding a transaction handle open. Update the
comment with all the other reasons and give some details.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This commit is contained in:
Filipe Manana 2026-02-02 16:47:02 +00:00 • committed by David Sterba
commit f754acce0f