bcachefs: Stripe deletion now checks what it's deleting

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

fs/bcachefs/ec.c

@@ -584,12 +584,12 @@ static int ec_stripe_mem_alloc(struct btree_trans *trans,
 		bch2_trans_relock(trans);
 }
 
-static ssize_t stripe_idx_to_delete(struct bch_fs *c)
+static u64 stripe_idx_to_delete(struct bch_fs *c)
 {
 	ec_stripes_heap *h = &c->ec_stripes_heap;
 
 	return h->used && h->data[0].blocks_nonempty == 0
-		? h->data[0].idx : -1;
+		? h->data[0].idx : 0;
 }
 
 static inline int ec_stripes_heap_cmp(ec_stripes_heap *h,
@@ -674,41 +674,81 @@ void bch2_stripes_heap_update(struct bch_fs *c,
 
 	heap_verify_backpointer(c, idx);
 
-	if (stripe_idx_to_delete(c) >= 0)
+	if (stripe_idx_to_delete(c))
 		bch2_do_stripe_deletes(c);
 }
 
 /* stripe deletion */
 
-static int ec_stripe_delete(struct bch_fs *c, size_t idx)
+static int ec_stripe_delete(struct btree_trans *trans, u64 idx)
 {
-	return bch2_btree_delete_range(c, BTREE_ID_stripes,
-				       POS(0, idx),
-				       POS(0, idx),
-				       0, NULL);
+	struct bch_fs *c = trans->c;
+	struct btree_iter iter;
+	struct bkey_s_c k;
+	struct bkey_s_c_stripe s;
+	int ret;
+
+	bch2_trans_iter_init(trans, &iter, BTREE_ID_stripes, POS(0, idx),
+			     BTREE_ITER_INTENT);
+	k = bch2_btree_iter_peek_slot(&iter);
+	ret = bkey_err(k);
+	if (ret)
+		goto err;
+
+	if (k.k->type != KEY_TYPE_stripe) {
+		bch2_fs_inconsistent(c, "attempting to delete nonexistent stripe %llu", idx);
+		ret = -EINVAL;
+		goto err;
+	}
+
+	s = bkey_s_c_to_stripe(k);
+	for (unsigned i = 0; i < s.v->nr_blocks; i++)
+		if (stripe_blockcount_get(s.v, i)) {
+			struct printbuf buf = PRINTBUF;
+
+			bch2_bkey_val_to_text(&buf, c, k);
+			bch2_fs_inconsistent(c, "attempting to delete nonempty stripe %s", buf.buf);
+			printbuf_exit(&buf);
+			ret = -EINVAL;
+			goto err;
+		}
+
+	ret = bch2_btree_delete_at(trans, &iter, 0);
+err:
+	bch2_trans_iter_exit(trans, &iter);
+	return ret;
 }
 
 static void ec_stripe_delete_work(struct work_struct *work)
 {
 	struct bch_fs *c =
 		container_of(work, struct bch_fs, ec_stripe_delete_work);
-	ssize_t idx;
+	struct btree_trans trans;
+	int ret;
+	u64 idx;
+
+	bch2_trans_init(&trans, c, 0, 0);
 
 	while (1) {
 		mutex_lock(&c->ec_stripes_heap_lock);
 		idx = stripe_idx_to_delete(c);
-		if (idx < 0) {
-			mutex_unlock(&c->ec_stripes_heap_lock);
-			break;
-		}
-
-		bch2_stripes_heap_del(c, genradix_ptr(&c->stripes, idx), idx);
+		if (idx)
+			bch2_stripes_heap_del(c, genradix_ptr(&c->stripes, idx), idx);
 		mutex_unlock(&c->ec_stripes_heap_lock);
 
-		if (ec_stripe_delete(c, idx))
+		if (!idx)
+			break;
+
+		ret = commit_do(&trans, NULL, NULL, BTREE_INSERT_NOFAIL,
+				ec_stripe_delete(&trans, idx));
+		if (ret) {
+			bch_err(c, "%s: err %s", __func__, bch2_err_str(ret));
 			break;
+		}
 	}
 
+	bch2_trans_exit(&trans);
+
 	bch2_write_ref_put(c, BCH_WRITE_REF_stripe_delete);
 }