per-netns ipv4 sysctl_tcp_mem

[firefly-linux-kernel-4.4.55.git] / net / ipv4 / sysctl_net_ipv4.c

diff --git a/net/ipv4/sysctl_net_ipv4.c b/net/ipv4/sysctl_net_ipv4.c
index 69fd7201129a742ee748932d52929d7fe548289c..bbd67abcb51de5e4135532dd91c6ecff24bbb896 100644 (file)
--- a/net/ipv4/sysctl_net_ipv4.c
+++ b/net/ipv4/sysctl_net_ipv4.c
@@ -14,6 +14,7 @@
 #include <linux/init.h>
 #include <linux/slab.h>
 #include <linux/nsproxy.h>
+#include <linux/swap.h>
 #include <net/snmp.h>
 #include <net/icmp.h>
 #include <net/ip.h>
@@ -174,6 +175,36 @@ static int proc_allowed_congestion_control(ctl_table *ctl,
        return ret;
 }
 
+static int ipv4_tcp_mem(ctl_table *ctl, int write,
+                          void __user *buffer, size_t *lenp,
+                          loff_t *ppos)
+{
+       int ret;
+       unsigned long vec[3];
+       struct net *net = current->nsproxy->net_ns;
+
+       ctl_table tmp = {
+               .data = &vec,
+               .maxlen = sizeof(vec),
+               .mode = ctl->mode,
+       };
+
+       if (!write) {
+               ctl->data = &net->ipv4.sysctl_tcp_mem;
+               return proc_doulongvec_minmax(ctl, write, buffer, lenp, ppos);
+       }
+
+       ret = proc_doulongvec_minmax(&tmp, write, buffer, lenp, ppos);
+       if (ret)
+               return ret;
+
+       net->ipv4.sysctl_tcp_mem[0] = vec[0];
+       net->ipv4.sysctl_tcp_mem[1] = vec[1];
+       net->ipv4.sysctl_tcp_mem[2] = vec[2];
+
+       return 0;
+}
+
 static struct ctl_table ipv4_table[] = {
        {
                .procname       = "tcp_timestamps",
@@ -432,13 +463,6 @@ static struct ctl_table ipv4_table[] = {
                .mode           = 0644,
                .proc_handler   = proc_dointvec
        },
-       {
-               .procname       = "tcp_mem",
-               .data           = &sysctl_tcp_mem,
-               .maxlen         = sizeof(sysctl_tcp_mem),
-               .mode           = 0644,
-               .proc_handler   = proc_doulongvec_minmax
-       },
        {
                .procname       = "tcp_wmem",
                .data           = &sysctl_tcp_wmem,
@@ -721,6 +745,12 @@ static struct ctl_table ipv4_net_table[] = {
                .mode           = 0644,
                .proc_handler   = ipv4_ping_group_range,
        },
+       {
+               .procname       = "tcp_mem",
+               .maxlen         = sizeof(init_net.ipv4.sysctl_tcp_mem),
+               .mode           = 0644,
+               .proc_handler   = ipv4_tcp_mem,
+       },
        { }
 };
 
@@ -734,6 +764,7 @@ EXPORT_SYMBOL_GPL(net_ipv4_ctl_path);
 static __net_init int ipv4_sysctl_init_net(struct net *net)
 {
        struct ctl_table *table;
+       unsigned long limit;
 
        table = ipv4_net_table;
        if (!net_eq(net, &init_net)) {
@@ -769,6 +800,12 @@ static __net_init int ipv4_sysctl_init_net(struct net *net)
 
        net->ipv4.sysctl_rt_cache_rebuild_count = 4;
 
+       limit = nr_free_buffer_pages() / 8;
+       limit = max(limit, 128UL);
+       net->ipv4.sysctl_tcp_mem[0] = limit / 4 * 3;
+       net->ipv4.sysctl_tcp_mem[1] = limit;
+       net->ipv4.sysctl_tcp_mem[2] = net->ipv4.sysctl_tcp_mem[0] * 2;
+
        net->ipv4.ipv4_hdr = register_net_sysctl_table(net,
                        net_ipv4_ctl_path, table);
        if (net->ipv4.ipv4_hdr == NULL)