Re: [PATCH v2 18/21] block, blksnap: snapshot

[Hillf Danton <hdanton@sina.com>]

On 9 Dec 2022 15:23:28 +0100 Sergei Shtepa <sergei.shtepa@veeam.com>
> +int snapshot_create(struct blk_snap_dev *dev_id_array, unsigned int count,
> +		    uuid_t *id)
> +{
> +	struct snapshot *snapshot = NULL;
> +	int ret;
> +	unsigned int inx;
> +
> +	pr_info("Create snapshot for devices:\n");
> +	for (inx = 0; inx < count; ++inx)
> +		pr_info("\t%u:%u\n", dev_id_array[inx].mj,
> +			dev_id_array[inx].mn);
> +
> +	ret = check_same_devices(dev_id_array, count);
> +	if (ret)
> +		return ret;
> +
> +	snapshot = snapshot_new(count);
> +	if (IS_ERR(snapshot)) {
> +		pr_err("Unable to create snapshot: failed to allocate snapshot structure\n");
> +		return PTR_ERR(snapshot);
> +	}
> +
> +	ret = -ENODEV;
> +	for (inx = 0; inx < count; ++inx) {
> +		dev_t dev_id =
> +			MKDEV(dev_id_array[inx].mj, dev_id_array[inx].mn);
> +		struct tracker *tracker;
> +
> +		tracker = tracker_create_or_get(dev_id);
> +		if (IS_ERR(tracker)) {
> +			pr_err("Unable to create snapshot\n");
> +			pr_err("Failed to add device [%u:%u] to snapshot tracking\n",
> +			       MAJOR(dev_id), MINOR(dev_id));
> +			ret = PTR_ERR(tracker);
> +			goto fail;
> +		}
> +
> +		snapshot->tracker_array[inx] = tracker;
> +		snapshot->count++;
> +	}
> +
> +	down_write(&snapshots_lock);
> +	list_add_tail(&snapshots, &snapshot->link);
> +	up_write(&snapshots_lock);

Given list_for_each_entry below, typo wrt &snapshots found in the fresh 2023?

> +
> +	uuid_copy(id, &snapshot->id);
> +	pr_info("Snapshot %pUb was created\n", &snapshot->id);
> +	return 0;
> +fail:
> +	pr_err("Snapshot cannot be created\n");
> +
> +	snapshot_put(snapshot);
> +	return ret;
> +}
> +
> +static struct snapshot *snapshot_get_by_id(uuid_t *id)
> +{
> +	struct snapshot *snapshot = NULL;
> +	struct snapshot *s;
> +
> +	down_read(&snapshots_lock);
> +	if (list_empty(&snapshots))
> +		goto out;
> +
> +	list_for_each_entry(s, &snapshots, link) {
> +		if (uuid_equal(&s->id, id)) {
> +			snapshot = s;
> +			snapshot_get(snapshot);
> +			break;
> +		}
> +	}
> +out:
> +	up_read(&snapshots_lock);
> +	return snapshot;
> +}