xen: Add Xen interface header files

Add Xen interface header files. These are taken fairly directly from
the Xen tree, but somewhat rearranged to suit the kernel's conventions.

Define macros and inline functions for doing hypercalls into the
hypervisor.

Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: Ian Pratt <ian.pratt@xensource.com>
Signed-off-by: Christian Limpach <Christian.Limpach@cl.cam.ac.uk>
Signed-off-by: Chris Wright <chrisw@sous-sol.org>

1 files changed, 158 insertions, 0 deletions

diff --git a/include/xen/interface/io/netif.h b/include/xen/interface/io/netif.h
new file mode 100644
index 000000000000..518481c95f18
--- /dev/null
+++ b/include/xen/interface/io/netif.h
@@ -0,0 +1,158 @@
+/******************************************************************************
+ * 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