uml: add VDE networking support

Added vde network backend in uml to introduce native Virtual Distributed
Ethernet support (using libvdeplug).

Signed-off-by: Luca Bigliardi <shammash@artha.org>
Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 136 insertions, 0 deletions

diff --git a/arch/um/drivers/vde_kern.c b/arch/um/drivers/vde_kern.c
new file mode 100644
index 000000000000..eb8cf31b820d
--- /dev/null
+++ b/arch/um/drivers/vde_kern.c
@@ -0,0 +1,136 @@
+/*
+ * Copyright (C) 2007 Luca Bigliardi (shammash@artha.org).
+ * Licensed under the GPL.
+ *
+ * Transport usage:
+ *  ethN=vde,<vde_switch>,<mac addr>,<port>,<group>,<mode>,<description>
+ *
+ */
+
+#include "linux/kernel.h"
+#include "linux/init.h"
+#include "linux/netdevice.h"
+#include "linux/etherdevice.h"
+#include "net_kern.h"
+#include "net_user.h"
+#include "vde.h"
+
+static void vde_init(struct net_device *dev, void *data)
+{
+	struct vde_init *init = data;
+	struct uml_net_private *pri;
+	struct vde_data *vpri;
+
+	pri = dev->priv;
+	vpri = (struct vde_data *) pri->user;
+
+	vpri->vde_switch = init->vde_switch;
+	vpri->descr = init->descr ? init->descr : "UML vde_transport";
+	vpri->args = NULL;
+	vpri->conn = NULL;
+	vpri->dev = dev;
+
+	printk(KERN_INFO "vde backend - %s, ", vpri->vde_switch ?
+	       vpri->vde_switch : "(default socket)");
+
+	vde_init_libstuff(vpri, init);
+
+	printk(KERN_INFO "\n");
+}
+
+static int vde_read(int fd, struct sk_buff **skb, struct uml_net_private *lp)
+{
+	struct vde_data *pri = (struct vde_data *) &lp->user;
+
+	if (pri->conn != NULL) {
+		*skb = ether_adjust_skb(*skb, ETH_HEADER_OTHER);
+		if (*skb == NULL)
+			return -ENOMEM;
+
+		return vde_user_read(pri->conn, skb_mac_header(*skb),
+				     (*skb)->dev->mtu + ETH_HEADER_OTHER);
+	}
+
+	printk(KERN_ERR "vde_read - we have no VDECONN to read from");
+	return -EBADF;
+}
+
+static int vde_write(int fd, struct sk_buff **skb, struct uml_net_private *lp)
+{
+	struct vde_data *pri = (struct vde_data *) &lp->user;
+
+	if (pri->conn != NULL)
+		return vde_user_write((void *)pri->conn, (*skb)->data,
+				      (*skb)->len);
+
+	printk(KERN_ERR "vde_write - we have no VDECONN to write to");
+	return -EBADF;
+}
+
+static const struct net_kern_info vde_kern_info = {
+	.init			= vde_init,
+	.protocol		= eth_protocol,
+	.read			= vde_read,
+	.write			= vde_write,
+};
+
+static int vde_setup(char *str, char **mac_out, void *data)
+{
+	struct vde_init *init = data;
+	char *remain, *port_str = NULL, *mode_str = NULL, *last;
+
+	*init = ((struct vde_init)
+		{ .vde_switch		= NULL,
+		  .descr		= NULL,
+		  .port			= 0,
+		  .group		= NULL,
+		  .mode			= 0 });
+
+	remain = split_if_spec(str, &init->vde_switch, mac_out, &port_str,
+				&init->group, &mode_str, &init->descr, NULL);
+
+	if (remain != NULL)
+		printk(KERN_WARNING "vde_setup - Ignoring extra data :"
+		       "'%s'\n", remain);
+
+	if (port_str != NULL) {
+		init->port = simple_strtoul(port_str, &last, 10);
+		if ((*last != '\0') || (last == port_str)) {
+			printk(KERN_ERR "vde_setup - Bad port : '%s'\n",
+						port_str);
+			return 0;
+		}
+	}
+
+	if (mode_str != NULL) {
+		init->mode = simple_strtoul(mode_str, &last, 8);
+		if ((*last != '\0') || (last == mode_str)) {
+			printk(KERN_ERR "vde_setup - Bad mode : '%s'\n",
+						mode_str);
+			return 0;
+		}
+	}
+
+	printk(KERN_INFO "Configured vde device: %s\n", init->vde_switch ?
+	       init->vde_switch : "(default socket)");
+
+	return 1;
+}
+
+static struct transport vde_transport = {
+	.list 		= LIST_HEAD_INIT(vde_transport.list),
+	.name 		= "vde",
+	.setup  	= vde_setup,
+	.user 		= &vde_user_info,
+	.kern 		= &vde_kern_info,
+	.private_size 	= sizeof(struct vde_data),
+	.setup_size 	= sizeof(struct vde_init),
+};
+
+static int register_vde(void)
+{
+	register_transport(&vde_transport);
+	return 0;
+}
+
+late_initcall(register_vde);