Commit 47fe65b1 authored by Kent Overstreet's avatar Kent Overstreet
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bcachefs: Add missing restart handling to check_topology() 



The next patch will add logging of the specific error being corrected in
repair paths to the journal; this means __bch2_fsck_err() can return
transaction restarts in places that previously weren't expecting them.

check_topology() is old code that doesn't use btree iterators for btree
node locking - it'll have to be rewritten in the future to work online.

Signed-off-by: default avatarKent Overstreet <kent.overstreet@linux.dev>
parent 19272b37

fs/bcachefs/btree_gc.c

+60 −35
Original line number Diff line number Diff line
@@ -397,7 +397,11 @@ static int bch2_btree_repair_topology_recurse(struct btree_trans *trans, struct 
			continue;

		}



		ret = btree_check_node_boundaries(trans, b, prev, cur, pulled_from_scan);

		ret = lockrestart_do(trans,

			btree_check_node_boundaries(trans, b, prev, cur, pulled_from_scan));

		if (ret < 0)

			goto err;



		if (ret == DID_FILL_FROM_SCAN) {

			new_pass = true;

			ret = 0;
@@ -438,7 +442,8 @@ static int bch2_btree_repair_topology_recurse(struct btree_trans *trans, struct 


	if (!ret && !IS_ERR_OR_NULL(prev)) {

		BUG_ON(cur);

		ret = btree_repair_node_end(trans, b, prev, pulled_from_scan);

		ret = lockrestart_do(trans,

			btree_repair_node_end(trans, b, prev, pulled_from_scan));

		if (ret == DID_FILL_FROM_SCAN) {

			new_pass = true;

			ret = 0;
@@ -519,27 +524,21 @@ static int bch2_btree_repair_topology_recurse(struct btree_trans *trans, struct 
	bch2_bkey_buf_exit(&prev_k, c);

	bch2_bkey_buf_exit(&cur_k, c);

	printbuf_exit(&buf);

	bch_err_fn(c, ret);

	return ret;

}



int bch2_check_topology(struct bch_fs *c)

static int bch2_check_root(struct btree_trans *trans, enum btree_id i,

			   bool *reconstructed_root)

{

	struct btree_trans *trans = bch2_trans_get(c);

	struct bpos pulled_from_scan = POS_MIN;

	struct bch_fs *c = trans->c;

	struct btree_root *r = bch2_btree_id_root(c, i);

	struct printbuf buf = PRINTBUF;

	int ret = 0;



	bch2_trans_srcu_unlock(trans);



	for (unsigned i = 0; i < btree_id_nr_alive(c) && !ret; i++) {

		struct btree_root *r = bch2_btree_id_root(c, i);

		bool reconstructed_root = false;



		printbuf_reset(&buf);

	bch2_btree_id_to_text(&buf, i);



	if (r->error) {

reconstruct_root:

		bch_info(c, "btree root %s unreadable, must recover from scan", buf.buf);



		r->alive = false;
@@ -556,12 +555,34 @@ int bch2_check_topology(struct bch_fs *c) 
			bch2_shoot_down_journal_keys(c, i, 1, BTREE_MAX_DEPTH, POS_MIN, SPOS_MAX);

			ret = bch2_get_scanned_nodes(c, i, 0, POS_MIN, SPOS_MAX);

			if (ret)

					break;

				goto err;

		}



			reconstructed_root = true;

		*reconstructed_root = true;

	}

err:

fsck_err:

	printbuf_exit(&buf);

	bch_err_fn(c, ret);

	return ret;

}



int bch2_check_topology(struct bch_fs *c)

{

	struct btree_trans *trans = bch2_trans_get(c);

	struct bpos pulled_from_scan = POS_MIN;

	int ret = 0;



	bch2_trans_srcu_unlock(trans);



	for (unsigned i = 0; i < btree_id_nr_alive(c) && !ret; i++) {

		bool reconstructed_root = false;

recover:

		ret = lockrestart_do(trans, bch2_check_root(trans, i, &reconstructed_root));

		if (ret)

			break;



		struct btree_root *r = bch2_btree_id_root(c, i);

		struct btree *b = r->b;



		btree_node_lock_nopath_nofail(trans, &b->c, SIX_LOCK_read);
@@ -575,17 +596,21 @@ int bch2_check_topology(struct bch_fs *c) 


			r->b = NULL;



			if (!reconstructed_root)

				goto reconstruct_root;

			if (!reconstructed_root) {

				r->error = -EIO;

				goto recover;

			}



			struct printbuf buf = PRINTBUF;

			bch2_btree_id_to_text(&buf, i);

			bch_err(c, "empty btree root %s", buf.buf);

			printbuf_exit(&buf);

			bch2_btree_root_alloc_fake_trans(trans, i, 0);

			r->alive = false;

			ret = 0;

		}

	}

fsck_err:

	printbuf_exit(&buf);



	bch2_trans_put(trans);

	return ret;

}