+ arg->replica_entries_bytes = (void *) dst_e - (void *) arg->replicas;
+
+ percpu_up_read(&c->mark_lock);
+ kfree(src);
+
+ if (ret)
+ goto err;
+ if (copy_to_user(user_arg, arg,
+ sizeof(*arg) + arg->replica_entries_bytes))
+ ret = -EFAULT;
+err:
+ kfree(arg);
+ return ret;
+}
+
+static long bch2_ioctl_dev_usage(struct bch_fs *c,
+ struct bch_ioctl_dev_usage __user *user_arg)
+{
+ struct bch_ioctl_dev_usage arg;
+ struct bch_dev_usage src;
+ struct bch_dev *ca;
+ unsigned i;
+
+ if (!test_bit(BCH_FS_STARTED, &c->flags))
+ return -EINVAL;
+
+ if (copy_from_user(&arg, user_arg, sizeof(arg)))
+ return -EFAULT;
+
+ if ((arg.flags & ~BCH_BY_INDEX) ||
+ arg.pad[0] ||
+ arg.pad[1] ||
+ arg.pad[2])
+ return -EINVAL;
+
+ ca = bch2_device_lookup(c, arg.dev, arg.flags);
+ if (IS_ERR(ca))
+ return PTR_ERR(ca);
+
+ src = bch2_dev_usage_read(ca);
+
+ arg.state = ca->mi.state;
+ arg.bucket_size = ca->mi.bucket_size;
+ arg.nr_buckets = ca->mi.nbuckets - ca->mi.first_bucket;
+ arg.buckets_ec = src.buckets_ec;
+
+ for (i = 0; i < BCH_DATA_NR; i++) {
+ arg.d[i].buckets = src.d[i].buckets;
+ arg.d[i].sectors = src.d[i].sectors;
+ arg.d[i].fragmented = src.d[i].fragmented;
+ }
+
+ percpu_ref_put(&ca->ref);
+
+ if (copy_to_user(user_arg, &arg, sizeof(arg)))
+ return -EFAULT;
+