1 files changed, 272 insertions, 0 deletions

diff --git a/net/ipv4/tcp_memcontrol.c b/net/ipv4/tcp_memcontrol.c
new file mode 100644
index 000000000000..7fed04f875c1
--- /dev/null
+++ b/net/ipv4/tcp_memcontrol.c
@@ -0,0 +1,272 @@
+#include <net/tcp.h>
+#include <net/tcp_memcontrol.h>
+#include <net/sock.h>
+#include <net/ip.h>
+#include <linux/nsproxy.h>
+#include <linux/memcontrol.h>
+#include <linux/module.h>
+
+static u64 tcp_cgroup_read(struct cgroup *cont, struct cftype *cft);
+static int tcp_cgroup_write(struct cgroup *cont, struct cftype *cft,
+			    const char *buffer);
+static int tcp_cgroup_reset(struct cgroup *cont, unsigned int event);
+
+static struct cftype tcp_files[] = {
+	{
+		.name = "kmem.tcp.limit_in_bytes",
+		.write_string = tcp_cgroup_write,
+		.read_u64 = tcp_cgroup_read,
+		.private = RES_LIMIT,
+	},
+	{
+		.name = "kmem.tcp.usage_in_bytes",
+		.read_u64 = tcp_cgroup_read,
+		.private = RES_USAGE,
+	},
+	{
+		.name = "kmem.tcp.failcnt",
+		.private = RES_FAILCNT,
+		.trigger = tcp_cgroup_reset,
+		.read_u64 = tcp_cgroup_read,
+	},
+	{
+		.name = "kmem.tcp.max_usage_in_bytes",
+		.private = RES_MAX_USAGE,
+		.trigger = tcp_cgroup_reset,
+		.read_u64 = tcp_cgroup_read,
+	},
+};
+
+static inline struct tcp_memcontrol *tcp_from_cgproto(struct cg_proto *cg_proto)
+{
+	return container_of(cg_proto, struct tcp_memcontrol, cg_proto);
+}
+
+static void memcg_tcp_enter_memory_pressure(struct sock *sk)
+{
+	if (sk->sk_cgrp->memory_pressure)
+		*sk->sk_cgrp->memory_pressure = 1;
+}
+EXPORT_SYMBOL(memcg_tcp_enter_memory_pressure);
+
+int tcp_init_cgroup(struct cgroup *cgrp, struct cgroup_subsys *ss)
+{
+	/*
+	 * The root cgroup does not use res_counters, but rather,
+	 * rely on the data already collected by the network
+	 * subsystem
+	 */
+	struct res_counter *res_parent = NULL;
+	struct cg_proto *cg_proto, *parent_cg;
+	struct tcp_memcontrol *tcp;
+	struct mem_cgroup *memcg = mem_cgroup_from_cont(cgrp);
+	struct mem_cgroup *parent = parent_mem_cgroup(memcg);
+	struct net *net = current->nsproxy->net_ns;
+
+	cg_proto = tcp_prot.proto_cgroup(memcg);
+	if (!cg_proto)
+		goto create_files;
+
+	tcp = tcp_from_cgproto(cg_proto);
+
+	tcp->tcp_prot_mem[0] = net->ipv4.sysctl_tcp_mem[0];
+	tcp->tcp_prot_mem[1] = net->ipv4.sysctl_tcp_mem[1];
+	tcp->tcp_prot_mem[2] = net->ipv4.sysctl_tcp_mem[2];
+	tcp->tcp_memory_pressure = 0;
+
+	parent_cg = tcp_prot.proto_cgroup(parent);
+	if (parent_cg)
+		res_parent = parent_cg->memory_allocated;
+
+	res_counter_init(&tcp->tcp_memory_allocated, res_parent);
+	percpu_counter_init(&tcp->tcp_sockets_allocated, 0);
+
+	cg_proto->enter_memory_pressure = memcg_tcp_enter_memory_pressure;
+	cg_proto->memory_pressure = &tcp->tcp_memory_pressure;
+	cg_proto->sysctl_mem = tcp->tcp_prot_mem;
+	cg_proto->memory_allocated = &tcp->tcp_memory_allocated;
+	cg_proto->sockets_allocated = &tcp->tcp_sockets_allocated;
+	cg_proto->memcg = memcg;
+
+create_files:
+	return cgroup_add_files(cgrp, ss, tcp_files,
+				ARRAY_SIZE(tcp_files));
+}
+EXPORT_SYMBOL(tcp_init_cgroup);
+
+void tcp_destroy_cgroup(struct cgroup *cgrp, struct cgroup_subsys *ss)
+{
+	struct mem_cgroup *memcg = mem_cgroup_from_cont(cgrp);
+	struct cg_proto *cg_proto;
+	struct tcp_memcontrol *tcp;
+	u64 val;
+
+	cg_proto = tcp_prot.proto_cgroup(memcg);
+	if (!cg_proto)
+		return;
+
+	tcp = tcp_from_cgproto(cg_proto);
+	percpu_counter_destroy(&tcp->tcp_sockets_allocated);
+
+	val = res_counter_read_u64(&tcp->tcp_memory_allocated, RES_USAGE);
+
+	if (val != RESOURCE_MAX)
+		jump_label_dec(&memcg_socket_limit_enabled);
+}
+EXPORT_SYMBOL(tcp_destroy_cgroup);
+
+static int tcp_update_limit(struct mem_cgroup *memcg, u64 val)
+{
+	struct net *net = current->nsproxy->net_ns;
+	struct tcp_memcontrol *tcp;
+	struct cg_proto *cg_proto;
+	u64 old_lim;
+	int i;
+	int ret;
+
+	cg_proto = tcp_prot.proto_cgroup(memcg);
+	if (!cg_proto)
+		return -EINVAL;
+
+	if (val > RESOURCE_MAX)
+		val = RESOURCE_MAX;
+
+	tcp = tcp_from_cgproto(cg_proto);
+
+	old_lim = res_counter_read_u64(&tcp->tcp_memory_allocated, RES_LIMIT);
+	ret = res_counter_set_limit(&tcp->tcp_memory_allocated, val);
+	if (ret)
+		return ret;
+
+	for (i = 0; i < 3; i++)
+		tcp->tcp_prot_mem[i] = min_t(long, val >> PAGE_SHIFT,
+					     net->ipv4.sysctl_tcp_mem[i]);
+
+	if (val == RESOURCE_MAX && old_lim != RESOURCE_MAX)
+		jump_label_dec(&memcg_socket_limit_enabled);
+	else if (old_lim == RESOURCE_MAX && val != RESOURCE_MAX)
+		jump_label_inc(&memcg_socket_limit_enabled);
+
+	return 0;
+}
+
+static int tcp_cgroup_write(struct cgroup *cont, struct cftype *cft,
+			    const char *buffer)
+{
+	struct mem_cgroup *memcg = mem_cgroup_from_cont(cont);
+	unsigned long long val;
+	int ret = 0;
+
+	switch (cft->private) {
+	case RES_LIMIT:
+		/* see memcontrol.c */
+		ret = res_counter_memparse_write_strategy(buffer, &val);
+		if (ret)
+			break;
+		ret = tcp_update_limit(memcg, val);
+		break;
+	default:
+		ret = -EINVAL;
+		break;
+	}
+	return ret;
+}
+
+static u64 tcp_read_stat(struct mem_cgroup *memcg, int type, u64 default_val)
+{
+	struct tcp_memcontrol *tcp;
+	struct cg_proto *cg_proto;
+
+	cg_proto = tcp_prot.proto_cgroup(memcg);
+	if (!cg_proto)
+		return default_val;
+
+	tcp = tcp_from_cgproto(cg_proto);
+	return res_counter_read_u64(&tcp->tcp_memory_allocated, type);
+}
+
+static u64 tcp_read_usage(struct mem_cgroup *memcg)
+{
+	struct tcp_memcontrol *tcp;
+	struct cg_proto *cg_proto;
+
+	cg_proto = tcp_prot.proto_cgroup(memcg);
+	if (!cg_proto)
+		return atomic_long_read(&tcp_memory_allocated) << PAGE_SHIFT;
+
+	tcp = tcp_from_cgproto(cg_proto);
+	return res_counter_read_u64(&tcp->tcp_memory_allocated, RES_USAGE);
+}
+
+static u64 tcp_cgroup_read(struct cgroup *cont, struct cftype *cft)
+{
+	struct mem_cgroup *memcg = mem_cgroup_from_cont(cont);
+	u64 val;
+
+	switch (cft->private) {
+	case RES_LIMIT:
+		val = tcp_read_stat(memcg, RES_LIMIT, RESOURCE_MAX);
+		break;
+	case RES_USAGE:
+		val = tcp_read_usage(memcg);
+		break;
+	case RES_FAILCNT:
+	case RES_MAX_USAGE:
+		val = tcp_read_stat(memcg, cft->private, 0);
+		break;
+	default:
+		BUG();
+	}
+	return val;
+}
+
+static int tcp_cgroup_reset(struct cgroup *cont, unsigned int event)
+{
+	struct mem_cgroup *memcg;
+	struct tcp_memcontrol *tcp;
+	struct cg_proto *cg_proto;
+
+	memcg = mem_cgroup_from_cont(cont);
+	cg_proto = tcp_prot.proto_cgroup(memcg);
+	if (!cg_proto)
+		return 0;
+	tcp = tcp_from_cgproto(cg_proto);
+
+	switch (event) {
+	case RES_MAX_USAGE:
+		res_counter_reset_max(&tcp->tcp_memory_allocated);
+		break;
+	case RES_FAILCNT:
+		res_counter_reset_failcnt(&tcp->tcp_memory_allocated);
+		break;
+	}
+
+	return 0;
+}
+
+unsigned long long tcp_max_memory(const struct mem_cgroup *memcg)
+{
+	struct tcp_memcontrol *tcp;
+	struct cg_proto *cg_proto;
+
+	cg_proto = tcp_prot.proto_cgroup((struct mem_cgroup *)memcg);
+	if (!cg_proto)
+		return 0;
+
+	tcp = tcp_from_cgproto(cg_proto);
+	return res_counter_read_u64(&tcp->tcp_memory_allocated, RES_LIMIT);
+}
+
+void tcp_prot_mem(struct mem_cgroup *memcg, long val, int idx)
+{
+	struct tcp_memcontrol *tcp;
+	struct cg_proto *cg_proto;
+
+	cg_proto = tcp_prot.proto_cgroup(memcg);
+	if (!cg_proto)
+		return;
+
+	tcp = tcp_from_cgproto(cg_proto);
+
+	tcp->tcp_prot_mem[idx] = val;
+}