1 /******************************************************************************
4 * Unified network-device I/O interface for Xen guest OSes.
6 * Copyright (c) 2003-2004, Keir Fraser
9 #ifndef __XEN_PUBLIC_IO_NETIF_H__
10 #define __XEN_PUBLIC_IO_NETIF_H__
13 #include "../grant_table.h"
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).
24 * This is the 'wire' format for packets:
25 * Request 1: xen_netif_tx_request -- XEN_NETTXF_* (any flags)
26 * [Request 2: xen_netif_extra_info] (only if request 1 has XEN_NETTXF_extra_info)
27 * [Request 3: xen_netif_extra_info] (only if request 2 has XEN_NETIF_EXTRA_MORE)
28 * Request 4: xen_netif_tx_request -- XEN_NETTXF_more_data
29 * Request 5: xen_netif_tx_request -- XEN_NETTXF_more_data
31 * Request N: xen_netif_tx_request -- 0
34 /* Protocol checksum field is blank in the packet (hardware offload)? */
35 #define _XEN_NETTXF_csum_blank (0)
36 #define XEN_NETTXF_csum_blank (1U<<_XEN_NETTXF_csum_blank)
38 /* Packet data has been validated against protocol checksum. */
39 #define _XEN_NETTXF_data_validated (1)
40 #define XEN_NETTXF_data_validated (1U<<_XEN_NETTXF_data_validated)
42 /* Packet continues in the next request descriptor. */
43 #define _XEN_NETTXF_more_data (2)
44 #define XEN_NETTXF_more_data (1U<<_XEN_NETTXF_more_data)
46 /* Packet to be followed by extra descriptor(s). */
47 #define _XEN_NETTXF_extra_info (3)
48 #define XEN_NETTXF_extra_info (1U<<_XEN_NETTXF_extra_info)
50 struct 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; /* XEN_NETTXF_* */
54 uint16_t id; /* Echoed in response message. */
55 uint16_t size; /* Packet size in bytes. */
58 /* Types of xen_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)
63 /* xen_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)
67 /* GSO types - only TCPv4 currently supported. */
68 #define XEN_NETIF_GSO_TYPE_TCPV4 (1)
71 * This structure needs to fit within both netif_tx_request and
72 * netif_rx_response for compatibility.
74 struct xen_netif_extra_info {
75 uint8_t type; /* XEN_NETIF_EXTRA_TYPE_* */
76 uint8_t flags; /* XEN_NETIF_EXTRA_FLAG_* */
81 * Maximum payload size of each segment. For
82 * example, for TCP this is just the path MSS.
87 * GSO type. This determines the protocol of
88 * the packet and any extra features required
89 * to segment the packet properly.
91 uint8_t type; /* XEN_NETIF_GSO_TYPE_* */
93 /* Future expansion. */
97 * GSO features. This specifies any extra GSO
98 * features required to process this packet,
99 * such as ECN support for TCPv4.
101 uint16_t features; /* XEN_NETIF_GSO_FEAT_* */
108 struct xen_netif_tx_response {
110 int16_t status; /* XEN_NETIF_RSP_* */
113 struct xen_netif_rx_request {
114 uint16_t id; /* Echoed in response message. */
115 grant_ref_t gref; /* Reference to incoming granted frame */
118 /* Packet data has been validated against protocol checksum. */
119 #define _XEN_NETRXF_data_validated (0)
120 #define XEN_NETRXF_data_validated (1U<<_XEN_NETRXF_data_validated)
122 /* Protocol checksum field is blank in the packet (hardware offload)? */
123 #define _XEN_NETRXF_csum_blank (1)
124 #define XEN_NETRXF_csum_blank (1U<<_XEN_NETRXF_csum_blank)
126 /* Packet continues in the next request descriptor. */
127 #define _XEN_NETRXF_more_data (2)
128 #define XEN_NETRXF_more_data (1U<<_XEN_NETRXF_more_data)
130 /* Packet to be followed by extra descriptor(s). */
131 #define _XEN_NETRXF_extra_info (3)
132 #define XEN_NETRXF_extra_info (1U<<_XEN_NETRXF_extra_info)
134 /* GSO Prefix descriptor. */
135 #define _XEN_NETRXF_gso_prefix (4)
136 #define XEN_NETRXF_gso_prefix (1U<<_XEN_NETRXF_gso_prefix)
138 struct xen_netif_rx_response {
140 uint16_t offset; /* Offset in page of start of received packet */
141 uint16_t flags; /* XEN_NETRXF_* */
142 int16_t status; /* -ve: BLKIF_RSP_* ; +ve: Rx'ed pkt size. */
146 * Generate netif ring structures and types.
149 DEFINE_RING_TYPES(xen_netif_tx,
150 struct xen_netif_tx_request,
151 struct xen_netif_tx_response);
152 DEFINE_RING_TYPES(xen_netif_rx,
153 struct xen_netif_rx_request,
154 struct xen_netif_rx_response);
156 #define XEN_NETIF_RSP_DROPPED -2
157 #define XEN_NETIF_RSP_ERROR -1
158 #define XEN_NETIF_RSP_OKAY 0
159 /* No response: used for auxiliary requests (e.g., xen_netif_extra_info). */
160 #define XEN_NETIF_RSP_NULL 1