1/****************************************************************************** 2 * netif.h 3 * 4 * Unified network-device I/O interface for Xen guest OSes. 5 * 6 * Copyright (c) 2003-2004, Keir Fraser 7 */ 8 9#ifndef __XEN_PUBLIC_IO_NETIF_H__ 10#define __XEN_PUBLIC_IO_NETIF_H__ 11 12#include "ring.h" 13#include "../grant_table.h" 14 15/* 16 * Notifications after enqueuing any type of message should be conditional on 17 * the appropriate req_event or rsp_event field in the shared ring. 18 * If the client sends notification for rx requests then it should specify 19 * feature 'feature-rx-notify' via xenbus. Otherwise the backend will assume 20 * that it cannot safely queue packets (as it may not be kicked to send them). 21 */ 22 23/* 24 * This is the 'wire' format for packets: 25 * Request 1: netif_tx_request -- NETTXF_* (any flags) 26 * [Request 2: netif_tx_extra] (only if request 1 has NETTXF_extra_info) 27 * [Request 3: netif_tx_extra] (only if request 2 has XEN_NETIF_EXTRA_MORE) 28 * Request 4: netif_tx_request -- NETTXF_more_data 29 * Request 5: netif_tx_request -- NETTXF_more_data 30 * ... 31 * Request N: netif_tx_request -- 0 32 */ 33 34/* Protocol checksum field is blank in the packet (hardware offload)? */ 35#define _NETTXF_csum_blank (0) 36#define NETTXF_csum_blank (1U<<_NETTXF_csum_blank) 37 38/* Packet data has been validated against protocol checksum. */ 39#define _NETTXF_data_validated (1) 40#define NETTXF_data_validated (1U<<_NETTXF_data_validated) 41 42/* Packet continues in the next request descriptor. */ 43#define _NETTXF_more_data (2) 44#define NETTXF_more_data (1U<<_NETTXF_more_data) 45 46/* Packet to be followed by extra descriptor(s). */ 47#define _NETTXF_extra_info (3) 48#define NETTXF_extra_info (1U<<_NETTXF_extra_info) 49 50struct xen_netif_tx_request { 51 grant_ref_t gref; /* Reference to buffer page */ 52 uint16_t offset; /* Offset within buffer page */ 53 uint16_t flags; /* NETTXF_* */ 54 uint16_t id; /* Echoed in response message. */ 55 uint16_t size; /* Packet size in bytes. */ 56}; 57 58/* Types of netif_extra_info descriptors. */ 59#define XEN_NETIF_EXTRA_TYPE_NONE (0) /* Never used - invalid */ 60#define XEN_NETIF_EXTRA_TYPE_GSO (1) /* u.gso */ 61#define XEN_NETIF_EXTRA_TYPE_MAX (2) 62 63/* netif_extra_info flags. */ 64#define _XEN_NETIF_EXTRA_FLAG_MORE (0) 65#define XEN_NETIF_EXTRA_FLAG_MORE (1U<<_XEN_NETIF_EXTRA_FLAG_MORE) 66 67/* GSO types - only TCPv4 currently supported. */ 68#define XEN_NETIF_GSO_TYPE_TCPV4 (1) 69 70/* 71 * This structure needs to fit within both netif_tx_request and 72 * netif_rx_response for compatibility. 73 */ 74struct xen_netif_extra_info { 75 uint8_t type; /* XEN_NETIF_EXTRA_TYPE_* */ 76 uint8_t flags; /* XEN_NETIF_EXTRA_FLAG_* */ 77 78 union { 79 struct { 80 /* 81 * Maximum payload size of each segment. For 82 * example, for TCP this is just the path MSS. 83 */ 84 uint16_t size; 85 86 /* 87 * GSO type. This determines the protocol of 88 * the packet and any extra features required 89 * to segment the packet properly. 90 */ 91 uint8_t type; /* XEN_NETIF_GSO_TYPE_* */ 92 93 /* Future expansion. */ 94 uint8_t pad; 95 96 /* 97 * GSO features. This specifies any extra GSO 98 * features required to process this packet, 99 * such as ECN support for TCPv4. 100 */ 101 uint16_t features; /* XEN_NETIF_GSO_FEAT_* */ 102 } gso; 103 104 uint16_t pad[3]; 105 } u; 106}; 107 108struct xen_netif_tx_response { 109 uint16_t id; 110 int16_t status; /* NETIF_RSP_* */ 111}; 112 113struct xen_netif_rx_request { 114 uint16_t id; /* Echoed in response message. */ 115 grant_ref_t gref; /* Reference to incoming granted frame */ 116}; 117 118/* Packet data has been validated against protocol checksum. */ 119#define _NETRXF_data_validated (0) 120#define NETRXF_data_validated (1U<<_NETRXF_data_validated) 121 122/* Protocol checksum field is blank in the packet (hardware offload)? */ 123#define _NETRXF_csum_blank (1) 124#define NETRXF_csum_blank (1U<<_NETRXF_csum_blank) 125 126/* Packet continues in the next request descriptor. */ 127#define _NETRXF_more_data (2) 128#define NETRXF_more_data (1U<<_NETRXF_more_data) 129 130/* Packet to be followed by extra descriptor(s). */ 131#define _NETRXF_extra_info (3) 132#define NETRXF_extra_info (1U<<_NETRXF_extra_info) 133 134struct xen_netif_rx_response { 135 uint16_t id; 136 uint16_t offset; /* Offset in page of start of received packet */ 137 uint16_t flags; /* NETRXF_* */ 138 int16_t status; /* -ve: BLKIF_RSP_* ; +ve: Rx'ed pkt size. */ 139}; 140 141/* 142 * Generate netif ring structures and types. 143 */ 144 145DEFINE_RING_TYPES(xen_netif_tx, 146 struct xen_netif_tx_request, 147 struct xen_netif_tx_response); 148DEFINE_RING_TYPES(xen_netif_rx, 149 struct xen_netif_rx_request, 150 struct xen_netif_rx_response); 151 152#define NETIF_RSP_DROPPED -2 153#define NETIF_RSP_ERROR -1 154#define NETIF_RSP_OKAY 0 155/* No response: used for auxiliary requests (e.g., netif_tx_extra). */ 156#define NETIF_RSP_NULL 1 157 158#endif 159