+static int proc_tcp_congestion_control(ctl_table *ctl, int write, struct file * filp,
+ void __user *buffer, size_t *lenp, loff_t *ppos)
+{
+ char val[TCP_CA_NAME_MAX];
+ ctl_table tbl = {
+ .data = val,
+ .maxlen = TCP_CA_NAME_MAX,
+ };
+ int ret;
+
+ tcp_get_default_congestion_control(val);
+
+ ret = proc_dostring(&tbl, write, filp, buffer, lenp, ppos);
+ if (write && ret == 0)
+ ret = tcp_set_default_congestion_control(val);
+ return ret;
+}
+
+static int sysctl_tcp_congestion_control(ctl_table *table, int __user *name,
+ int nlen, void __user *oldval,
+ size_t __user *oldlenp,
+ void __user *newval, size_t newlen,
+ void **context)
+{
+ char val[TCP_CA_NAME_MAX];
+ ctl_table tbl = {
+ .data = val,
+ .maxlen = TCP_CA_NAME_MAX,
+ };
+ int ret;
+
+ tcp_get_default_congestion_control(val);
+ ret = sysctl_string(&tbl, name, nlen, oldval, oldlenp, newval, newlen,
+ context);
+ if (ret == 0 && newval && newlen)
+ ret = tcp_set_default_congestion_control(val);
+ return ret;
+}
+
+