From ed44ee7b686bf8c6d6f78b82c2e4187f02b00aa4 Mon Sep 17 00:00:00 2001 From: Ben Pfaff Date: Mon, 11 Jan 2010 11:06:56 -0800 Subject: [PATCH] datapath: Improve comments. --- include/openvswitch/datapath-protocol.h | 58 +++++++++++++++++-------- 1 file changed, 39 insertions(+), 19 deletions(-) diff --git a/include/openvswitch/datapath-protocol.h b/include/openvswitch/datapath-protocol.h index ce187efa1..6d3e90074 100644 --- a/include/openvswitch/datapath-protocol.h +++ b/include/openvswitch/datapath-protocol.h @@ -117,30 +117,50 @@ struct odp_stats { #define ODPL_SFLOW (1 << _ODPL_SFLOW_NR) #define ODPL_ALL (ODPL_MISS | ODPL_ACTION | ODPL_SFLOW) -/* Format of messages read from datapath fd. */ +/** + * struct odp_msg - format of messages read from datapath fd. + * @type: One of the %_ODPL_* constants. + * @length: Total length of message, including this header. + * @port: Port that received the packet embedded in this message. + * @reserved: Not currently used. Should be set to 0. + * @arg: Argument value whose meaning depends on @type. + * + * For @type == %_ODPL_MISS_NR, the header is followed by packet data. The + * @arg member is unused and set to 0. + * + * For @type == %_ODPL_ACTION_NR, the header is followed by packet data. The + * @arg member is copied from the &struct odp_action_controller that caused + * the &struct odp_msg to be composed. + * + * For @type == %_ODPL_SFLOW_NR, the header is followed by &struct + * odp_sflow_sample_header, then by an array of &union odp_action (the number + * of which is specified in &struct odp_sflow_sample_header), then by packet + * data. + */ struct odp_msg { - __u32 type; /* _ODPL_MISS_NR or _ODPL_ACTION_NR. */ - __u32 length; /* Message length, including header. */ - __u16 port; /* Port on which frame was received. */ + __u32 type; + __u32 length; + __u16 port; __u16 reserved; - __u32 arg; /* Argument value specified in action. */ - - /* - * Followed by: - * - * ODPL_MISS, ODPL_ACTION: packet data. - * - * ODPL_SFLOW: "struct odp_sflow_sample_header", followed by - * an array of "union odp_action"s, followed by packet data. - */ + __u32 arg; }; -/* Header added to sFlow sampled packet. */ +/** + * struct odp_sflow_sample_header - header added to sFlow sampled packet. + * @sample_pool: Number of packets that were candidates for sFlow sampling, + * regardless of whether they were actually chosen and sent down to userspace. + * @n_actions: Number of "union odp_action"s immediately following this header. + * @reserved: Pads the structure up to a 64-bit boundary. Should be set to + * zero. + * + * This header follows &struct odp_msg when that structure's @type is + * %_ODPL_SFLOW_NR, and it is itself followed by an array of &union odp_action + * (the number of which is specified in @n_actions) and then by packet data. + */ struct odp_sflow_sample_header { - __u64 sample_pool; /* Number of potentially sampled packets. */ - __u32 n_actions; /* Number of following "union odp_action"s. */ - __u32 reserved; /* Pad up to 64-bit boundary. */ - /* Followed by n_action "union odp_action"s. */ + __u64 sample_pool; + __u32 n_actions; + __u32 reserved; }; #define ODP_PORT_INTERNAL (1 << 0) /* This port is simulated. */ -- 2.43.0