Add flowtable flows de-acceleration procfs option

net/netfilter/xt_FLOWOFFLOAD.c

@@ -14,6 +14,7 @@
 #include <net/netfilter/nf_conntrack_extend.h>
 #include <net/netfilter/nf_conntrack_helper.h>
 #include <net/netfilter/nf_flow_table.h>
+#include <linux/proc_fs.h>
 
 static struct nf_flowtable nf_flowtable;
 static HLIST_HEAD(hooks);
@@ -392,10 +393,40 @@ static struct notifier_block flow_offload_netdev_notifier = {
 	.notifier_call	= flow_offload_netdev_event,
 };
 
+static struct proc_dir_entry *procfs_subdir_entry;
+
+static ssize_t procfs_callback(struct file *f, const char __user *u,
+                              size_t count, loff_t *p)
+{
+       nf_flow_table_cleanup(NULL, NULL);
+       return count;
+}
+
+#define PROC_SUBDIR "nf-flow-table-control"
+#define PROC_ACTION "clear"
+
+static void register_flow_table_ctrl(void)
+{
+       static struct file_operations ops = {
+               .owner = THIS_MODULE,
+               .write = procfs_callback
+       };
+
+       procfs_subdir_entry = proc_mkdir(PROC_SUBDIR, NULL);
+       proc_create(PROC_ACTION, 0220, procfs_subdir_entry, &ops);
+}
+
+static void unregister_flow_table_ctrl(void)
+{
+       remove_proc_entry(PROC_ACTION, procfs_subdir_entry);
+       remove_proc_entry(PROC_SUBDIR, NULL);
+}
+
 static int __init xt_flowoffload_tg_init(void)
 {
 	int ret;
 
+	register_flow_table_ctrl();
 	register_netdevice_notifier(&flow_offload_netdev_notifier);
 
 	INIT_DELAYED_WORK(&hook_work, xt_flowoffload_hook_work);
@@ -415,6 +446,7 @@ static void __exit xt_flowoffload_tg_exit(void)
 {
 	xt_unregister_target(&offload_tg_reg);
 	xt_flowoffload_table_cleanup(&nf_flowtable);
+	unregister_flow_table_ctrl();
 	unregister_netdevice_notifier(&flow_offload_netdev_notifier);
 }