Hi all, One thing that's been missing for a long time is the ability to tell underlying storage that it can unmap the unused space on the realtime device. This short series exposes this functionality through FITRIM. Callers that want ranged FITRIM should be aware that the realtime space exists in the offset range after the data device. However, it is anticipated that most callers pass in offset=0 len=-1ULL and will not notice or care. If you're going to start using this mess, you probably ought to just pull from my git trees, which are linked below. This is an extraordinary way to destroy everything. Enjoy! Comments and questions are, as always, welcome. --D kernel git tree: https://git.kernel.org/cgit/linux/kernel/git/djwong/xfs-linux.git/log/?h=realtime-discard --- fs/xfs/xfs_discard.c | 167 +++++++++++++++++++++++++++++++++++++++++++------- fs/xfs/xfs_trace.h | 20 ++++++ 2 files changed, 164 insertions(+), 23 deletions(-)