[PATCH 6.7 615/713] bcachefs: Fix BTREE_ITER_FILTER_SNAPSHOTS on inodes btree

From: Sasha Levin
Date: Sun Mar 24 2024 - 22:03:17 EST


From: Kent Overstreet <kent.overstreet@xxxxxxxxx>

commit 204f45140faa0772d2ca1b3de96d1c0fb3db8e77 upstream.

If we're in FILTER_SNAPSHOTS mode and we start scanning a range of the
keyspace where no keys are visible in the current snapshot, we have a
problem - we'll scan for a very long time before scanning terminates.

Awhile back, this was fixed for most cases with peek_upto() (and
assertions that enforce that it's being used).

But the fix missed the fact that the inodes btree is different - every
key offset is in a different snapshot tree, not just the inode field.

Fixes:
Signed-off-by: Kent Overstreet <kent.overstreet@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
fs/bcachefs/btree_iter.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/fs/bcachefs/btree_iter.c b/fs/bcachefs/btree_iter.c
index da594e0067697..816ecc3375196 100644
--- a/fs/bcachefs/btree_iter.c
+++ b/fs/bcachefs/btree_iter.c
@@ -2094,7 +2094,9 @@ struct bkey_s_c bch2_btree_iter_peek_upto(struct btree_iter *iter, struct bpos e
* isn't monotonically increasing before FILTER_SNAPSHOTS, and
* that's what we check against in extents mode:
*/
- if (k.k->p.inode > end.inode)
+ if (unlikely(!(iter->flags & BTREE_ITER_IS_EXTENTS)
+ ? bkey_gt(k.k->p, end)
+ : k.k->p.inode > end.inode))
goto end;

if (iter->update_path &&
--
2.43.0