[PATCH] bcachefs: Fix btree for nonexistent tree depth

[Kent Overstreet]

The fix for when we should increase tree depth in journal replay was
entirely bogus.

We should only increase the tree depth in journal replay when recovery
from btree node scan, and then only for keys found by btree node scan.

This needs additional work - we should be shooting down existing
interior node pointers when recovery from scan, they shouldn't be
showing up here.

Fixes: b47a82ff4772 ("bcachefs: Only run 'increase_depth' for keys from btree 
node csan")
Cc: Alan Huang <mmpgour...@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstr...@linux.dev>
---
 fs/bcachefs/recovery.c | 23 +++++++++++++++++------
 1 file changed, 17 insertions(+), 6 deletions(-)

diff --git a/fs/bcachefs/recovery.c b/fs/bcachefs/recovery.c
index 974f8bf9a574..0def4ecb7f88 100644
--- a/fs/bcachefs/recovery.c
+++ b/fs/bcachefs/recovery.c
@@ -273,24 +273,35 @@ static int bch2_journal_replay_key(struct btree_trans 
*trans,
                goto out;
 
        struct btree_path *path = btree_iter_path(trans, &iter);
-       if (unlikely(!btree_path_node(path, k->level) &&
-                    !k->allocated)) {
+       if (unlikely(!btree_path_node(path, k->level))) {
                struct bch_fs *c = trans->c;
 
+               CLASS(printbuf, buf)();
+               prt_str(&buf, "btree=");
+               bch2_btree_id_to_text(&buf, k->btree_id);
+               prt_printf(&buf, " level=%u ", k->level);
+               bch2_bkey_val_to_text(&buf, c, bkey_i_to_s_c(k->k));
+
                if (!(c->recovery.passes_complete & 
(BIT_ULL(BCH_RECOVERY_PASS_scan_for_btree_nodes)|
                                                     
BIT_ULL(BCH_RECOVERY_PASS_check_topology)))) {
-                       bch_err(c, "have key in journal replay for btree depth 
that does not exist, confused");
+                       bch_err(c, "have key in journal replay for btree depth 
that does not exist, confused\n%s",
+                               buf.buf);
                        ret = -EINVAL;
                }
-#if 0
+
+               if (!k->allocated) {
+                       bch_notice(c, "dropping key in journal replay for depth 
that does not exist because we're recovering from scan\n%s",
+                                  buf.buf);
+                       k->overwritten = true;
+                       goto out;
+               }
+
                bch2_trans_iter_exit(trans, &iter);
                bch2_trans_node_iter_init(trans, &iter, k->btree_id, k->k->k.p,
                                          BTREE_MAX_DEPTH, 0, iter_flags);
                ret =   bch2_btree_iter_traverse(trans, &iter) ?:
                        bch2_btree_increase_depth(trans, iter.path, 0) ?:
                        -BCH_ERR_transaction_restart_nested;
-#endif
-               k->overwritten = true;
                goto out;
        }
 
-- 
2.50.0