Re: [PATCH v6 05/10] NFSD first draft of async copy

[bfields@fieldses.org (J. Bruce Fields)]

On Tue, Oct 24, 2017 at 01:47:47PM -0400, Olga Kornievskaia wrote:
> +	copy->cp_clp = cstate->clp;
> +	memcpy(&copy->fh, &cstate->current_fh.fh_handle,
> +		sizeof(struct knfsd_fh));
> +	copy->net = SVC_NET(rqstp);
> +	if (!copy->cp_synchronous) {

I was thinking we might want to do a synchronous copy anyway in some
cases: e.g. if the copy is relatively small or if the filesystem
supports clone.

But I guess that's a premature optimization; better to keep this as you
have it for now.

--b.

> +		status = nfsd4_init_copy_res(copy, 0);
> +		async_copy = kzalloc(sizeof(struct nfsd4_copy), GFP_KERNEL);
> +		if (!async_copy) {
> +			status = nfserrno(-ENOMEM);
> +			goto out;
> +		}
> +		dup_copy_fields(copy, async_copy);
> +		memcpy(&copy->cp_res.cb_stateid, &copy->cp_dst_stateid,
> +			sizeof(copy->cp_dst_stateid));
> +		spin_lock(&async_copy->cp_clp->async_lock);
> +		list_add(&async_copy->copies,
> +				&async_copy->cp_clp->async_copies);
> +		spin_unlock(&async_copy->cp_clp->async_lock);
> +		async_copy->copy_task = kthread_create(nfsd4_do_async_copy,
> +				async_copy, "%s", "copy thread");
> +		if (IS_ERR(async_copy->copy_task)) {
> +			status = PTR_ERR(async_copy->copy_task);
> +			goto out_err_dec;
> +		}
> +		wake_up_process(async_copy->copy_task);
> +	} else {
> +		status = nfsd4_do_copy(copy, 1);