bcachefs: bch2_dev_journal_bucket_delete()

Recover from "journal and btree in same bucket".

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

fs/bcachefs/buckets.c

@@ -221,6 +221,20 @@ static int bch2_check_fix_ptr(struct btree_trans *trans,
 			 bch2_bkey_val_to_text(&buf, c, k), buf.buf))) {
 		if (!p.ptr.cached &&
 		    data_type == BCH_DATA_btree) {
+			switch (g->data_type) {
+			case BCH_DATA_sb:
+				bch_err(c, "btree and superblock in the same bucket - cannot repair");
+				ret = -BCH_ERR_fsck_repair_unimplemented;
+				goto out;
+			case BCH_DATA_journal:
+				ret = bch2_dev_journal_bucket_delete(ca, PTR_BUCKET_NR(ca, &p.ptr));
+				bch_err_msg(c, ret, "error deleting journal bucket %zu",
+					    PTR_BUCKET_NR(ca, &p.ptr));
+				if (ret)
+					goto out;
+				break;
+			}
+
 			g->data_type		= data_type;
 			g->stripe_sectors	= 0;
 			g->dirty_sectors	= 0;

fs/bcachefs/journal.c

@@ -1304,6 +1304,66 @@ int bch2_set_nr_journal_buckets(struct bch_fs *c, struct bch_dev *ca,
 	return ret;
 }
 
+int bch2_dev_journal_bucket_delete(struct bch_dev *ca, u64 b)
+{
+	struct bch_fs *c = ca->fs;
+	struct journal *j = &c->journal;
+	struct journal_device *ja = &ca->journal;
+
+	guard(mutex)(&c->sb_lock);
+	unsigned pos;
+	for (pos = 0; pos < ja->nr; pos++)
+		if (ja->buckets[pos] == b)
+			break;
+
+	if (pos == ja->nr) {
+		bch_err(ca, "journal bucket %llu not found when deleting", b);
+		return -EINVAL;
+	}
+
+	u64 *new_buckets = kcalloc(ja->nr, sizeof(u64), GFP_KERNEL);;
+	if (!new_buckets)
+		return -BCH_ERR_ENOMEM_set_nr_journal_buckets;
+
+	memcpy(new_buckets, ja->buckets, ja->nr * sizeof(u64));
+	memmove(&new_buckets[pos],
+		&new_buckets[pos + 1],
+		(ja->nr - 1 - pos) * sizeof(new_buckets[0]));
+
+	int ret = bch2_journal_buckets_to_sb(c, ca, ja->buckets, ja->nr - 1) ?:
+		bch2_write_super(c);
+	if (ret) {
+		kfree(new_buckets);
+		return ret;
+	}
+
+	scoped_guard(spinlock, &j->lock) {
+		if (pos < ja->discard_idx)
+			--ja->discard_idx;
+		if (pos < ja->dirty_idx_ondisk)
+			--ja->dirty_idx_ondisk;
+		if (pos < ja->dirty_idx)
+			--ja->dirty_idx;
+		if (pos < ja->cur_idx)
+			--ja->cur_idx;
+
+		ja->nr--;
+
+		memmove(&ja->buckets[pos],
+			&ja->buckets[pos + 1],
+			(ja->nr - pos) * sizeof(ja->buckets[0]));
+
+		memmove(&ja->bucket_seq[pos],
+			&ja->bucket_seq[pos + 1],
+			(ja->nr - pos) * sizeof(ja->bucket_seq[0]));
+
+		bch2_journal_space_available(j);
+	}
+
+	kfree(new_buckets);
+	return 0;
+}
+
 int bch2_dev_journal_alloc(struct bch_dev *ca, bool new_fs)
 {
 	struct bch_fs *c = ca->fs;

fs/bcachefs/journal.h

@@ -444,8 +444,9 @@ struct journal_buf *bch2_next_write_buffer_flush_journal_buf(struct journal *, u
 void __bch2_journal_debug_to_text(struct printbuf *, struct journal *);
 void bch2_journal_debug_to_text(struct printbuf *, struct journal *);
 
-int bch2_set_nr_journal_buckets(struct bch_fs *, struct bch_dev *,
-				unsigned nr);
+int bch2_set_nr_journal_buckets(struct bch_fs *, struct bch_dev *, unsigned);
+int bch2_dev_journal_bucket_delete(struct bch_dev *, u64);
+
 int bch2_dev_journal_alloc(struct bch_dev *, bool);
 int bch2_fs_journal_alloc(struct bch_fs *);
 

fs/bcachefs/str_hash.c

@@ -239,7 +239,8 @@ int __bch2_str_hash_check_key(struct btree_trans *trans,
 
 	for_each_btree_key_norestart(trans, iter, desc->btree_id,
 				     SPOS(hash_k.k->p.inode, hash, hash_k.k->p.snapshot),
-				     BTREE_ITER_slots, k, ret) {
+				     BTREE_ITER_slots|
+				     BTREE_ITER_with_updates, k, ret) {
 		if (bkey_eq(k.k->p, hash_k.k->p))
 			break;
 
@@ -286,10 +287,11 @@ int __bch2_str_hash_check_key(struct btree_trans *trans,
 			goto duplicate_entries;
 
 		ret =   bch2_hash_delete_at(trans, *desc, hash_info, k_iter,
+					    BTREE_ITER_with_updates|
 					    BTREE_UPDATE_internal_snapshot_node) ?:
 			bch2_fsck_update_backpointers(trans, s, *desc, hash_info, new) ?:
 			bch2_trans_commit(trans, NULL, NULL, BCH_TRANS_COMMIT_no_enospc) ?:
-			-BCH_ERR_transaction_restart_nested;
+			-BCH_ERR_transaction_restart_commit;
 		goto out;
 	}
 fsck_err:
@@ -323,6 +325,6 @@ int __bch2_str_hash_check_key(struct btree_trans *trans,
 	}
 
 	ret = bch2_trans_commit(trans, NULL, NULL, 0) ?:
-		-BCH_ERR_transaction_restart_nested;
+		-BCH_ERR_transaction_restart_commit;
 	goto out;
 }