bcachefs: Journal keys overlay fixes

 - In the btree iterator code that overlays keys from the journal, we
   were incorrectly specifying level=0 instead of the btree_path's
   current level in a few places
 - When we didn't do journal replay, we shouldn't free the journal keys:
   this fixes cmd_list and cmd_dump, which run in norecovery mode
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

fs/bcachefs/btree_iter.c

@@ -1834,7 +1834,7 @@ struct bkey_s_c btree_trans_peek_journal(struct btree_trans *trans,
 {
 	struct bkey_i *next_journal =
 		bch2_btree_journal_peek(trans, iter,
-				k.k ? k.k->p : iter->path->l[0].b->key.k.p);
+				k.k ? k.k->p : path_l(iter->path)->b->key.k.p);
 
 	if (next_journal) {
 		iter->k = next_journal->k;

fs/bcachefs/recovery.c

@@ -1398,7 +1398,8 @@ int bch2_fs_recovery(struct bch_fs *c)
 	set_bit(BCH_FS_FSCK_DONE, &c->flags);
 	bch2_flush_fsck_errs(c);
 
-	if (!c->opts.keep_journal) {
+	if (!c->opts.keep_journal &&
+	    test_bit(JOURNAL_REPLAY_DONE, &c->journal.flags)) {
 		bch2_journal_keys_free(&c->journal_keys);
 		bch2_journal_entries_free(c);
 	}