xfs: remove xfs_last_used_zone

This was my first attempt at caching the last used zone.  But it turns out
for O_DIRECT or RWF_DONTCACHE that operate concurrently or in very short
sequence, the bmap btree does not record a written extent yet, so it fails.
Because it then still finds the last written zone it can lead to a weird
ping-pong around a few zones with writers seeing different values.

Remove it entirely as the later added xfs_cached_zone actually does a
much better job enforcing the locality as the zone is associated with the
inode in the MRU cache as soon as the zone is selected.

Fixes: 4e4d52075577 ("xfs: add the zoned space allocator")
Signed-off-by: Christoph Hellwig <[email protected]>
Tested-by: Damien Le Moal <[email protected]>
Reviewed-by: Hans Holmberg <[email protected]>
Signed-off-by: Carlos Maiolino <[email protected]>

0 files changed, 0 insertions, 0 deletions