[PATCH 1/2] bcachefs: Count BCH_DATA_parity backpointers correctly

[PATCH 1/2] bcachefs: Count BCH_DATA_parity backpointers correctly

[Kent Overstreet]

These are counted as stripe data in the corresponding alloc keys.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
---
 fs/bcachefs/backpointers.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/fs/bcachefs/backpointers.c b/fs/bcachefs/backpointers.c
index c9dfc3657696..8da1b68821a0 100644
--- a/fs/bcachefs/backpointers.c
+++ b/fs/bcachefs/backpointers.c
@@ -50,6 +50,8 @@ void bch2_backpointer_to_text(struct printbuf *out, struct bch_fs *c, struct bke
 	}
 
 	bch2_btree_id_level_to_text(out, bp.v->btree_id, bp.v->level);
+	prt_str(out, " data_type=");
+	bch2_prt_data_type(out, bp.v->data_type);
 	prt_printf(out, " suboffset=%u len=%u gen=%u pos=",
 		   (u32) bp.k->p.offset & ~(~0U << MAX_EXTENT_COMPRESS_RATIO_SHIFT),
 		   bp.v->bucket_len,
@@ -791,6 +793,7 @@ static enum alloc_sector_counter data_type_to_alloc_counter(enum bch_data_type t
 	case BCH_DATA_cached:
 		return ALLOC_cached;
 	case BCH_DATA_stripe:
+	case BCH_DATA_parity:
 		return ALLOC_stripe;
 	default:
 		BUG();
-- 
2.49.0

[PATCH 2/2] bcachefs: Handle backpointers with unknown data types

[Kent Overstreet]

New data types might be added later, so we don't want to disallow
unknown data types - that'll be a compatibility hassle later. Instead,
ignore them.

Reported-by: syzbot+3a290f5ff67ca3023834@syzkaller.appspotmail.com
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
---
 fs/bcachefs/backpointers.c | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/fs/bcachefs/backpointers.c b/fs/bcachefs/backpointers.c
index 8da1b68821a0..20c497f0c2cb 100644
--- a/fs/bcachefs/backpointers.c
+++ b/fs/bcachefs/backpointers.c
@@ -784,7 +784,7 @@ enum alloc_sector_counter {
 	ALLOC_SECTORS_NR
 };
 
-static enum alloc_sector_counter data_type_to_alloc_counter(enum bch_data_type t)
+static int data_type_to_alloc_counter(enum bch_data_type t)
 {
 	switch (t) {
 	case BCH_DATA_btree:
@@ -796,7 +796,7 @@ static enum alloc_sector_counter data_type_to_alloc_counter(enum bch_data_type t
 	case BCH_DATA_parity:
 		return ALLOC_stripe;
 	default:
-		BUG();
+		return -1;
 	}
 }
 
@@ -847,7 +847,11 @@ static int check_bucket_backpointer_mismatch(struct btree_trans *trans, struct b
 		if (bp.v->bucket_gen != a->gen)
 			continue;
 
-		sectors[data_type_to_alloc_counter(bp.v->data_type)] += bp.v->bucket_len;
+		int alloc_counter = data_type_to_alloc_counter(bp.v->data_type);
+		if (alloc_counter < 0)
+			continue;
+
+		sectors[alloc_counter] += bp.v->bucket_len;
 	};
 	bch2_trans_iter_exit(trans, &iter);
 	if (ret)
-- 
2.49.0