From mboxrd@z Thu Jan  1 00:00:00 1970
From: Paolo Abeni <pabeni@redhat.com>
Date: Tue, 16 Mar 2021 18:33:55 +0100
Subject: [Cluster-devel] [PATCHv2 dlm/next 7/8] fs: dlm: add reliable
 connection if reconnect
In-Reply-To: <20210310191745.80824-8-aahringo@redhat.com>
References: <20210310191745.80824-1-aahringo@redhat.com>
	<20210310191745.80824-8-aahringo@redhat.com>
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On Wed, 2021-03-10 at 14:17 -0500, Alexander Aring wrote:
> @@ -116,32 +905,21 @@ int dlm_process_incoming_buffer(int nodeid, unsigned char *buf, int len)
>  		if (msglen > len)
>  			break;
>  
> -		switch (hd->h_cmd) {
> -		case DLM_MSG:
> -			if (msglen < sizeof(struct dlm_message)) {
> -				log_print("dlm msg too small: %u, will skip this message",
> -					  msglen);
> -				goto skip;
> -			}
> -
> +		idx = srcu_read_lock(&nodes_srcu);
> +		switch (le32_to_cpu(hd->h_version)) {
> +		case DLM_VERSION_3_1:
> +			dlm_midcomms_receive_buffer_3_1((union dlm_packet *)ptr, nodeid);
>  			break;
> -		case DLM_RCOM:
> -			if (msglen < sizeof(struct dlm_rcom)) {
> -				log_print("dlm rcom msg too small: %u, will skip this message",
> -					  msglen);
> -				goto skip;
> -			}
> -
> +		case DLM_VERSION_3_2:
> +			dlm_midcomms_receive_buffer_3_2((union dlm_packet *)ptr, nodeid);
>  			break;
>  		default:
> -			log_print("unsupported h_cmd received: %u, will skip this message",
> -				  hd->h_cmd);
> -			goto skip;
> +			log_print("received invalid version header: %u from node %d, will skip this message",
> +				  le32_to_cpu(hd->h_version), nodeid);
> +			break;
>  		}
> +		srcu_read_unlock(&nodes_srcu, idx);

I think the srcu usage will be more clear if the lock/unlock are moved
inside dlm_midcomms_receive_buffer_3_2() and dlm_midcomms_receive_buffe
r_3_1(), so that they wrap the node lookup and access.

Cheers,

Paolo