Re: [PATCH 07/18] nvme/tcp: allocate socket file

[Sagi Grimberg <sagi@grimberg.me>]

On 3/21/23 14:43, Hannes Reinecke wrote:
> When using the TLS upcall we need to allocate a socket file such
> that the userspace daemon is able to use the socket.
> 
> Signed-off-by: Hannes Reinecke <hare@suse.de>
> ---
>   drivers/nvme/host/tcp.c | 21 +++++++++++++++++++--
>   1 file changed, 19 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/nvme/host/tcp.c b/drivers/nvme/host/tcp.c
> index 0512eb289dcf..0438d42f4179 100644
> --- a/drivers/nvme/host/tcp.c
> +++ b/drivers/nvme/host/tcp.c
> @@ -115,6 +115,7 @@ enum nvme_tcp_recv_state {
>   struct nvme_tcp_ctrl;
>   struct nvme_tcp_queue {
>   	struct socket		*sock;
> +	struct file		*sock_file;
>   	struct work_struct	io_work;
>   	int			io_cpu;
>   
> @@ -1330,7 +1331,12 @@ static void nvme_tcp_free_queue(struct nvme_ctrl *nctrl, int qid)
>   	}
>   
>   	noreclaim_flag = memalloc_noreclaim_save();
> -	sock_release(queue->sock);
> +	if (queue->sock_file) {
> +		fput(queue->sock_file);
> +		queue->sock_file = NULL;
> +		/* ->sock will be released by fput() */
> +	} else
> +		sock_release(queue->sock);
>   	memalloc_noreclaim_restore(noreclaim_flag);
>   
>   	kfree(queue->pdu);
> @@ -1526,6 +1532,12 @@ static int nvme_tcp_alloc_queue(struct nvme_ctrl *nctrl, int qid)
>   		goto err_destroy_mutex;
>   	}
>   
> +	queue->sock_file = sock_alloc_file(queue->sock, O_CLOEXEC, NULL);
> +	if (IS_ERR(queue->sock_file)) {
> +		ret = PTR_ERR(queue->sock_file);
> +		queue->sock_file = NULL;
> +		goto err_sock;
> +	}

If a sock_file is always allocated, and fail the connection if
unsuccessful, why do you check on its existence when freeing the queue?

>   	nvme_tcp_reclassify_socket(queue->sock);
>   
>   	/* Single syn retry */
> @@ -1647,7 +1659,12 @@ static int nvme_tcp_alloc_queue(struct nvme_ctrl *nctrl, int qid)
>   	if (queue->hdr_digest || queue->data_digest)
>   		nvme_tcp_free_crypto(queue);
>   err_sock:
> -	sock_release(queue->sock);
> +	if (queue->sock_file) {
> +		fput(queue->sock_file);
> +		queue->sock_file = NULL;
> +		/* ->sock will be released by fput() */
> +	} else
> +		sock_release(queue->sock);
>   	queue->sock = NULL;
>   err_destroy_mutex:
>   	mutex_destroy(&queue->send_mutex);