/* [<][>][^][v][top][bottom][index][help] */
/******************************************************************************
* netif.h
*
* Unified network-device I/O interface for Xen guest OSes.
*
* Copyright (c) 2003-2004, Keir Fraser
*/
#ifndef __XEN_PUBLIC_IO_NETIF_H__
#define __XEN_PUBLIC_IO_NETIF_H__
#include "ring.h"
#include "../grant_table.h"
/*
* Notifications after enqueuing any type of message should be conditional on
* the appropriate req_event or rsp_event field in the shared ring.
* If the client sends notification for rx requests then it should specify
* feature 'feature-rx-notify' via xenbus. Otherwise the backend will assume
* that it cannot safely queue packets (as it may not be kicked to send them).
*/
/*
* This is the 'wire' format for packets:
* Request 1: netif_tx_request -- NETTXF_* (any flags)
* [Request 2: netif_tx_extra] (only if request 1 has NETTXF_extra_info)
* [Request 3: netif_tx_extra] (only if request 2 has XEN_NETIF_EXTRA_MORE)
* Request 4: netif_tx_request -- NETTXF_more_data
* Request 5: netif_tx_request -- NETTXF_more_data
* ...
* Request N: netif_tx_request -- 0
*/
/* Protocol checksum field is blank in the packet (hardware offload)? */
#define _NETTXF_csum_blank (0)
#define NETTXF_csum_blank (1U<<_NETTXF_csum_blank)
/* Packet data has been validated against protocol checksum. */
#define _NETTXF_data_validated (1)
#define NETTXF_data_validated (1U<<_NETTXF_data_validated)
/* Packet continues in the next request descriptor. */
#define _NETTXF_more_data (2)
#define NETTXF_more_data (1U<<_NETTXF_more_data)
/* Packet to be followed by extra descriptor(s). */
#define _NETTXF_extra_info (3)
#define NETTXF_extra_info (1U<<_NETTXF_extra_info)
struct xen_netif_tx_request {
grant_ref_t gref; /* Reference to buffer page */
uint16_t offset; /* Offset within buffer page */
uint16_t flags; /* NETTXF_* */
uint16_t id; /* Echoed in response message. */
uint16_t size; /* Packet size in bytes. */
};
/* Types of netif_extra_info descriptors. */
#define XEN_NETIF_EXTRA_TYPE_NONE (0) /* Never used - invalid */
#define XEN_NETIF_EXTRA_TYPE_GSO (1) /* u.gso */
#define XEN_NETIF_EXTRA_TYPE_MAX (2)
/* netif_extra_info flags. */
#define _XEN_NETIF_EXTRA_FLAG_MORE (0)
#define XEN_NETIF_EXTRA_FLAG_MORE (1U<<_XEN_NETIF_EXTRA_FLAG_MORE)
/* GSO types - only TCPv4 currently supported. */
#define XEN_NETIF_GSO_TYPE_TCPV4 (1)
/*
* This structure needs to fit within both netif_tx_request and
* netif_rx_response for compatibility.
*/
struct xen_netif_extra_info {
uint8_t type; /* XEN_NETIF_EXTRA_TYPE_* */
uint8_t flags; /* XEN_NETIF_EXTRA_FLAG_* */
union {
struct {
/*
* Maximum payload size of each segment. For
* example, for TCP this is just the path MSS.
*/
uint16_t size;
/*
* GSO type. This determines the protocol of
* the packet and any extra features required
* to segment the packet properly.
*/
uint8_t type; /* XEN_NETIF_GSO_TYPE_* */
/* Future expansion. */
uint8_t pad;
/*
* GSO features. This specifies any extra GSO
* features required to process this packet,
* such as ECN support for TCPv4.
*/
uint16_t features; /* XEN_NETIF_GSO_FEAT_* */
} gso;
uint16_t pad[3];
} u;
};
struct xen_netif_tx_response {
uint16_t id;
int16_t status; /* NETIF_RSP_* */
};
struct xen_netif_rx_request {
uint16_t id; /* Echoed in response message. */
grant_ref_t gref; /* Reference to incoming granted frame */
};
/* Packet data has been validated against protocol checksum. */
#define _NETRXF_data_validated (0)
#define NETRXF_data_validated (1U<<_NETRXF_data_validated)
/* Protocol checksum field is blank in the packet (hardware offload)? */
#define _NETRXF_csum_blank (1)
#define NETRXF_csum_blank (1U<<_NETRXF_csum_blank)
/* Packet continues in the next request descriptor. */
#define _NETRXF_more_data (2)
#define NETRXF_more_data (1U<<_NETRXF_more_data)
/* Packet to be followed by extra descriptor(s). */
#define _NETRXF_extra_info (3)
#define NETRXF_extra_info (1U<<_NETRXF_extra_info)
struct xen_netif_rx_response {
uint16_t id;
uint16_t offset; /* Offset in page of start of received packet */
uint16_t flags; /* NETRXF_* */
int16_t status; /* -ve: BLKIF_RSP_* ; +ve: Rx'ed pkt size. */
};
/*
* Generate netif ring structures and types.
*/
DEFINE_RING_TYPES(xen_netif_tx,
struct xen_netif_tx_request,
struct xen_netif_tx_response);
DEFINE_RING_TYPES(xen_netif_rx,
struct xen_netif_rx_request,
struct xen_netif_rx_response);
#define NETIF_RSP_DROPPED -2
#define NETIF_RSP_ERROR -1
#define NETIF_RSP_OKAY 0
/* No response: used for auxiliary requests (e.g., netif_tx_extra). */
#define NETIF_RSP_NULL 1
#endif