bcachefs: Persist 64 bit io clocks

Originally, bcachefs - going back to bcache - stored, for each bucket, a
16 bit counter corresponding to how long it had been since the bucket
was read from. But, this required periodically rescaling counters on
every bucket to avoid wraparound. That wasn't an issue in bcache, where
we'd perodically rewrite the per bucket metadata all at once, but in
bcachefs we're trying to avoid having to walk every single bucket.

This patch switches to persisting 64 bit io clocks, corresponding to the
64 bit bucket timestaps introduced in the previous patch with
KEY_TYPE_alloc_v2.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

1 files changed, 1 insertions, 1 deletions

diff --git a/fs/bcachefs/buckets_types.h b/fs/bcachefs/buckets_types.h
index 99ab9f48ba9d..b6ea67506cc2 100644
--- a/fs/bcachefs/buckets_types.h
+++ b/fs/bcachefs/buckets_types.h
@@ -37,7 +37,7 @@ struct bucket {
 		const struct bucket_mark mark;
 	};
 
-	u16				io_time[2];
+	u64				io_time[2];
 	u8				oldest_gen;
 	u8				gc_gen;
 	unsigned			gen_valid:1;