First sketch of a new net device API.

src/include/errno.h

@@ -124,6 +124,7 @@
 #define EINVAL		0xd3
 #define ENOENT		0xd4
 #define EAFNOSUPPORT	0xd5
+#define EAGAIN		0xd6
 
 /* Data structures and declarations */
 

src/include/gpxe/if_ether.h

@@ -12,11 +12,12 @@
 #define	ETH_MAX_MTU		(ETH_FRAME_LEN-ETH_HLEN)
 #endif
 
-#define ETH_P_IP	0x0800		/* Internet Protocl Packet */
-#define ETH_P_ARP	0x0806		/* Address Resolution Protocol */
-#define ETH_P_RARP	0x8035		/* Reverse Address resolution Protocol */
-#define ETH_P_IPV6	0x86DD		/* IPv6 over blueblook */
-#define ETH_P_SLOW	0x8809		/* Ethernet slow protocols */
+#define ETH_P_RAW	0x0000	/* Raw packet */
+#define ETH_P_IP	0x0800	/* Internet Protocl Packet */
+#define ETH_P_ARP	0x0806	/* Address Resolution Protocol */
+#define ETH_P_RARP	0x8035	/* Reverse Address resolution Protocol */
+#define ETH_P_IPV6	0x86DD	/* IPv6 over blueblook */
+#define ETH_P_SLOW	0x8809	/* Ethernet slow protocols */
 
 /** An Ethernet link-layer header */
 struct ethhdr {

src/include/gpxe/netdevice.h

@@ -100,6 +100,8 @@ struct net_device {
 	 * For Ethernet, this is the MAC address.
 	 */
 	uint8_t ll_addr[MAX_LLH_ADDR_LEN];
+	/** Linked list of network devices */
+	struct list_head devices;
 	/** List of network interfaces */
 	struct list_head interfaces;
 	/** Driver private data */
@@ -117,7 +119,7 @@ struct net_interface {
 	/** Underlying net device */
 	struct net_device *netdev;
 	/** Linked list of interfaces for this device */
-	struct list_head list;
+	struct list_head interfaces;
 	/** Network-layer protocol
 	 *
 	 * This is an ETH_P_XXX constant, in network byte order.
@@ -127,21 +129,6 @@ struct net_interface {
 	uint8_t net_addr_len;
 	/** Network-layer address */
 	uint8_t net_addr[MAX_NET_ADDR_LEN];
-	/** Packet processor
-	 *
-	 * @v netif	Network interface
-	 * @v pkb	Packet buffer
-	 * @ret rc	Return status code
-	 *
-	 * This method is called for packets arriving on the
-	 * associated network device that match this interface's
-	 * network-layer protocol.
-	 *
-	 * When this method is called, the link-layer header will
-	 * already have been stripped from the packet.
-	 */
-	int ( * process ) ( struct net_interface *netif,
-			    struct pk_buff *pkb );
 	/** Fill in packet metadata
 	 *
 	 * @v netif	Network interface
@@ -154,6 +141,21 @@ struct net_interface {
 	 */
 	int ( * add_llh_metadata ) ( struct net_interface *netif,
 				     struct pk_buff *pkb );
+	/** Received packet processor
+	 *
+	 * @v netif	Network interface
+	 * @v pkb	Packet buffer
+	 * @ret rc	Return status code
+	 *
+	 * This method is called for packets arriving on the
+	 * associated network device that match this interface's
+	 * network-layer protocol.
+	 *
+	 * When this method is called, the link-layer header will
+	 * already have been stripped from the packet.
+	 */
+	int ( * rx_packet ) ( struct net_interface *netif,
+			      struct pk_buff *pkb );
 };
 
 /**
@@ -168,15 +170,22 @@ static inline struct net_interface *
 netdev_find_netif ( const struct net_device *netdev, uint16_t net_proto ) {
 	struct net_interface *netif;
 
-	list_for_each_entry ( netif, &netdev->interfaces, list ) {
+	list_for_each_entry ( netif, &netdev->interfaces, interfaces ) {
 		if ( netif->net_proto == net_proto )
 			return netif;
 	}
 	return NULL;
 }
 
+extern int register_netdevice ( struct net_device *netdev );
+extern void unregister_netdevice ( struct net_device *netdev );
 extern int netdev_send ( struct net_device *netdev, struct pk_buff *pkb );
+extern int netdev_poll ( struct net_device *netdev, struct pk_buff *pkb );
 extern int netif_send ( struct net_interface *netif, struct pk_buff *pkb );
+extern int netdev_rx_packet ( struct net_device *netdev, struct pk_buff *pkb );
+extern int net_poll ( struct pk_buff *pkb, struct net_device **netdev );
+
+
 
 extern struct net_device static_single_netdev;
 
@@ -186,9 +195,6 @@ extern struct net_device static_single_netdev;
 	static_single_netdev.priv = priv_data;	\
 	&static_single_netdev; } )
 
-extern int register_netdevice ( struct net_device *netdev );
-
-extern void unregister_netdevice ( struct net_device *netdev );
 
 static inline void free_netdevice ( struct net_device *netdev __unused ) {
 	/* Do nothing */

src/net/netdevice.c

@@ -0,0 +1,163 @@
+/*
+ * Copyright (C) 2006 Michael Brown <mbrown@fensystems.co.uk>.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <stdint.h>
+#include <byteswap.h>
+#include <errno.h>
+#include <gpxe/if_ether.h>
+#include <gpxe/pkbuff.h>
+#include <gpxe/netdevice.h>
+
+/** @file
+ *
+ * Network devices and network interfaces
+ *
+ */
+
+/** List of all registered network devices */
+static LIST_HEAD ( net_devices );
+
+/**
+ * Register network device
+ *
+ * @v netdev	Network device
+ * @ret rc	Return status code
+ *
+ * Adds the network device to the list of network devices.
+ */
+int register_netdevice ( struct net_device *netdev ) {
+	list_add ( &netdev->devices, &net_devices );
+	return 0;
+}
+
+/**
+ * Unregister network device
+ *
+ * @v netdev	Network device
+ *
+ * Removes the network device from the list of network devices.
+ */
+void unregister_netdevice ( struct net_device *netdev ) {
+	list_del ( &netdev->devices );
+}
+
+/**
+ * Transmit packet via network device
+ *
+ * @v netdev	Network device
+ * @v pkb	Packet buffer
+ * @ret rc	Return status code
+ *
+ * Transmits the packet via the network device.  The @c pkb link-layer
+ * metadata must already have been filled in, and space for the
+ * link-layer header must already be present in the packet buffer.
+ */
+int netdev_send ( struct net_device *netdev, struct pk_buff *pkb ) {
+	int rc;
+
+	if ( pkb->net_proto != ETH_P_RAW ) {
+		if ( ( rc = netdev->build_llh ( netdev, pkb ) ) != 0 )
+			return rc;
+	}
+	return netdev->transmit ( netdev, pkb );
+}
+
+/**
+ * Poll for packet on network device
+ *
+ * @v netdev	Network device
+ * @v pkb	Packet buffer
+ * @ret rc	Return status code
+ *
+ * Polls the network device for a packet.  If a packet is available,
+ * it will be added to the packet buffer, and the link-layer metadata
+ * fields in @c pkb will be filled in.
+ */
+int netdev_poll ( struct net_device *netdev, struct pk_buff *pkb ) {
+	int rc;
+
+	if ( ( rc = netdev->poll ( netdev, pkb ) ) != 0 )
+		return rc;
+	return netdev->parse_llh ( netdev, pkb );
+}
+
+/**
+ * Transmit packet via network interface
+ *
+ * @v netif	Network interface
+ * @v pkb	Packet buffer
+ * @ret rc	Return status code
+ *
+ * Transmits the packet via the network interface.  The packet must
+ * start with a network-layer header (e.g. an IP header, for an IP
+ * interface).  The packet contents are undefined on return.
+ */
+int netif_send ( struct net_interface *netif, struct pk_buff *pkb ) {
+	struct net_device *netdev = netif->netdev;
+	int rc;
+
+	if ( ( rc = netif->add_llh_metadata ( netif, pkb ) ) != 0 )
+		return rc;
+	pkb_push ( pkb, netdev->ll_hlen );
+	return netdev_send ( netdev, pkb );
+}
+
+/**
+ * Process received packet
+ *
+ * @v netif	Network interface
+ * @v pkb	Packet buffer
+ * @ret rc	Return status code
+ *
+ * Processes a packet received via netdev_poll().  The interface
+ * corresponding to the network-layer protocol is identified, the
+ * link-layer header is stripped from the packet and the packet is
+ * passed to the net_interface::rx_packet() method.
+ */
+int netdev_rx_packet ( struct net_device *netdev, struct pk_buff *pkb ) {
+	struct net_interface *netif;
+
+	netif = netdev_find_netif ( netdev, pkb->net_proto );
+	if ( ! netif )
+		return -EAFNOSUPPORT;
+
+	pkb_pull ( pkb, netdev->ll_hlen );
+	return netif->rx_packet ( netif, pkb );
+}
+
+/**
+ * Poll for packet on all network devices
+ *
+ * @v pkb	Packet buffer
+ * @ret netdev	Network device
+ * @ret rc	Return status code
+ *
+ * Polls all network devices for a packet.  If a packet is available
+ * on any interface, @c netdev will be filled in and the packet will
+ * be received as per netdev_poll().
+ */
+int net_poll ( struct pk_buff *pkb, struct net_device **netdev ) {
+	int rc;
+
+	list_for_each_entry ( (*netdev), &net_devices, devices ) {
+		if ( ( rc = netdev_poll ( *netdev, pkb ) ) == 0 )
+			return rc;
+	}
+
+	return -EAGAIN;
+}