2020-03-27 21:48:38 +00:00
|
|
|
// SPDX-License-Identifier: GPL-2.0
|
|
|
|
/* Multipath TCP
|
|
|
|
*
|
|
|
|
* Copyright (c) 2019, Intel Corporation.
|
|
|
|
*/
|
2020-04-03 09:14:08 +00:00
|
|
|
#define pr_fmt(fmt) "MPTCP: " fmt
|
|
|
|
|
2020-03-27 21:48:38 +00:00
|
|
|
#include <linux/kernel.h>
|
|
|
|
#include <net/tcp.h>
|
|
|
|
#include <net/mptcp.h>
|
|
|
|
#include "protocol.h"
|
|
|
|
|
|
|
|
static struct workqueue_struct *pm_wq;
|
|
|
|
|
|
|
|
/* path manager command handlers */
|
|
|
|
|
|
|
|
int mptcp_pm_announce_addr(struct mptcp_sock *msk,
|
|
|
|
const struct mptcp_addr_info *addr)
|
|
|
|
{
|
2020-03-27 21:48:41 +00:00
|
|
|
pr_debug("msk=%p, local_id=%d", msk, addr->id);
|
|
|
|
|
|
|
|
msk->pm.local = *addr;
|
|
|
|
WRITE_ONCE(msk->pm.addr_signal, true);
|
|
|
|
return 0;
|
2020-03-27 21:48:38 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
int mptcp_pm_remove_addr(struct mptcp_sock *msk, u8 local_id)
|
|
|
|
{
|
|
|
|
return -ENOTSUPP;
|
|
|
|
}
|
|
|
|
|
|
|
|
int mptcp_pm_remove_subflow(struct mptcp_sock *msk, u8 remote_id)
|
|
|
|
{
|
|
|
|
return -ENOTSUPP;
|
|
|
|
}
|
|
|
|
|
|
|
|
/* path manager event handlers */
|
|
|
|
|
|
|
|
void mptcp_pm_new_connection(struct mptcp_sock *msk, int server_side)
|
|
|
|
{
|
|
|
|
struct mptcp_pm_data *pm = &msk->pm;
|
|
|
|
|
|
|
|
pr_debug("msk=%p, token=%u side=%d", msk, msk->token, server_side);
|
|
|
|
|
|
|
|
WRITE_ONCE(pm->server_side, server_side);
|
|
|
|
}
|
|
|
|
|
|
|
|
bool mptcp_pm_allow_new_subflow(struct mptcp_sock *msk)
|
|
|
|
{
|
2020-03-27 21:48:41 +00:00
|
|
|
struct mptcp_pm_data *pm = &msk->pm;
|
|
|
|
int ret;
|
|
|
|
|
|
|
|
pr_debug("msk=%p subflows=%d max=%d allow=%d", msk, pm->subflows,
|
|
|
|
pm->subflows_max, READ_ONCE(pm->accept_subflow));
|
|
|
|
|
|
|
|
/* try to avoid acquiring the lock below */
|
|
|
|
if (!READ_ONCE(pm->accept_subflow))
|
|
|
|
return false;
|
|
|
|
|
|
|
|
spin_lock_bh(&pm->lock);
|
|
|
|
ret = pm->subflows < pm->subflows_max;
|
|
|
|
if (ret && ++pm->subflows == pm->subflows_max)
|
|
|
|
WRITE_ONCE(pm->accept_subflow, false);
|
|
|
|
spin_unlock_bh(&pm->lock);
|
|
|
|
|
|
|
|
return ret;
|
|
|
|
}
|
|
|
|
|
|
|
|
/* return true if the new status bit is currently cleared, that is, this event
|
|
|
|
* can be server, eventually by an already scheduled work
|
|
|
|
*/
|
|
|
|
static bool mptcp_pm_schedule_work(struct mptcp_sock *msk,
|
|
|
|
enum mptcp_pm_status new_status)
|
|
|
|
{
|
|
|
|
pr_debug("msk=%p status=%x new=%lx", msk, msk->pm.status,
|
|
|
|
BIT(new_status));
|
|
|
|
if (msk->pm.status & BIT(new_status))
|
|
|
|
return false;
|
|
|
|
|
|
|
|
msk->pm.status |= BIT(new_status);
|
|
|
|
if (queue_work(pm_wq, &msk->pm.work))
|
|
|
|
sock_hold((struct sock *)msk);
|
|
|
|
return true;
|
2020-03-27 21:48:38 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
void mptcp_pm_fully_established(struct mptcp_sock *msk)
|
|
|
|
{
|
2020-03-27 21:48:41 +00:00
|
|
|
struct mptcp_pm_data *pm = &msk->pm;
|
|
|
|
|
2020-03-27 21:48:38 +00:00
|
|
|
pr_debug("msk=%p", msk);
|
2020-03-27 21:48:41 +00:00
|
|
|
|
|
|
|
/* try to avoid acquiring the lock below */
|
|
|
|
if (!READ_ONCE(pm->work_pending))
|
|
|
|
return;
|
|
|
|
|
|
|
|
spin_lock_bh(&pm->lock);
|
|
|
|
|
|
|
|
if (READ_ONCE(pm->work_pending))
|
|
|
|
mptcp_pm_schedule_work(msk, MPTCP_PM_ESTABLISHED);
|
|
|
|
|
|
|
|
spin_unlock_bh(&pm->lock);
|
2020-03-27 21:48:38 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
void mptcp_pm_connection_closed(struct mptcp_sock *msk)
|
|
|
|
{
|
|
|
|
pr_debug("msk=%p", msk);
|
|
|
|
}
|
|
|
|
|
|
|
|
void mptcp_pm_subflow_established(struct mptcp_sock *msk,
|
|
|
|
struct mptcp_subflow_context *subflow)
|
|
|
|
{
|
2020-03-27 21:48:41 +00:00
|
|
|
struct mptcp_pm_data *pm = &msk->pm;
|
|
|
|
|
2020-03-27 21:48:38 +00:00
|
|
|
pr_debug("msk=%p", msk);
|
2020-03-27 21:48:41 +00:00
|
|
|
|
|
|
|
if (!READ_ONCE(pm->work_pending))
|
|
|
|
return;
|
|
|
|
|
|
|
|
spin_lock_bh(&pm->lock);
|
|
|
|
|
|
|
|
if (READ_ONCE(pm->work_pending))
|
|
|
|
mptcp_pm_schedule_work(msk, MPTCP_PM_SUBFLOW_ESTABLISHED);
|
|
|
|
|
|
|
|
spin_unlock_bh(&pm->lock);
|
2020-03-27 21:48:38 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
void mptcp_pm_subflow_closed(struct mptcp_sock *msk, u8 id)
|
|
|
|
{
|
|
|
|
pr_debug("msk=%p", msk);
|
|
|
|
}
|
|
|
|
|
|
|
|
void mptcp_pm_add_addr_received(struct mptcp_sock *msk,
|
|
|
|
const struct mptcp_addr_info *addr)
|
|
|
|
{
|
2020-03-27 21:48:41 +00:00
|
|
|
struct mptcp_pm_data *pm = &msk->pm;
|
|
|
|
|
|
|
|
pr_debug("msk=%p remote_id=%d accept=%d", msk, addr->id,
|
|
|
|
READ_ONCE(pm->accept_addr));
|
|
|
|
|
|
|
|
/* avoid acquiring the lock if there is no room for fouther addresses */
|
|
|
|
if (!READ_ONCE(pm->accept_addr))
|
|
|
|
return;
|
|
|
|
|
|
|
|
spin_lock_bh(&pm->lock);
|
|
|
|
|
|
|
|
/* be sure there is something to signal re-checking under PM lock */
|
|
|
|
if (READ_ONCE(pm->accept_addr) &&
|
|
|
|
mptcp_pm_schedule_work(msk, MPTCP_PM_ADD_ADDR_RECEIVED))
|
|
|
|
pm->remote = *addr;
|
|
|
|
|
|
|
|
spin_unlock_bh(&pm->lock);
|
2020-03-27 21:48:38 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
/* path manager helpers */
|
|
|
|
|
|
|
|
bool mptcp_pm_addr_signal(struct mptcp_sock *msk, unsigned int remaining,
|
|
|
|
struct mptcp_addr_info *saddr)
|
|
|
|
{
|
2020-03-27 21:48:41 +00:00
|
|
|
int ret = false;
|
|
|
|
|
|
|
|
spin_lock_bh(&msk->pm.lock);
|
|
|
|
|
|
|
|
/* double check after the lock is acquired */
|
|
|
|
if (!mptcp_pm_should_signal(msk))
|
|
|
|
goto out_unlock;
|
|
|
|
|
|
|
|
if (remaining < mptcp_add_addr_len(msk->pm.local.family))
|
|
|
|
goto out_unlock;
|
|
|
|
|
|
|
|
*saddr = msk->pm.local;
|
|
|
|
WRITE_ONCE(msk->pm.addr_signal, false);
|
|
|
|
ret = true;
|
|
|
|
|
|
|
|
out_unlock:
|
|
|
|
spin_unlock_bh(&msk->pm.lock);
|
|
|
|
return ret;
|
2020-03-27 21:48:38 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
int mptcp_pm_get_local_id(struct mptcp_sock *msk, struct sock_common *skc)
|
|
|
|
{
|
2020-03-27 21:48:51 +00:00
|
|
|
return mptcp_pm_nl_get_local_id(msk, skc);
|
2020-03-27 21:48:38 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
static void pm_worker(struct work_struct *work)
|
|
|
|
{
|
2020-03-27 21:48:41 +00:00
|
|
|
struct mptcp_pm_data *pm = container_of(work, struct mptcp_pm_data,
|
|
|
|
work);
|
|
|
|
struct mptcp_sock *msk = container_of(pm, struct mptcp_sock, pm);
|
|
|
|
struct sock *sk = (struct sock *)msk;
|
|
|
|
|
|
|
|
lock_sock(sk);
|
|
|
|
spin_lock_bh(&msk->pm.lock);
|
|
|
|
|
|
|
|
pr_debug("msk=%p status=%x", msk, pm->status);
|
|
|
|
if (pm->status & BIT(MPTCP_PM_ADD_ADDR_RECEIVED)) {
|
|
|
|
pm->status &= ~BIT(MPTCP_PM_ADD_ADDR_RECEIVED);
|
2020-03-27 21:48:51 +00:00
|
|
|
mptcp_pm_nl_add_addr_received(msk);
|
2020-03-27 21:48:41 +00:00
|
|
|
}
|
|
|
|
if (pm->status & BIT(MPTCP_PM_ESTABLISHED)) {
|
|
|
|
pm->status &= ~BIT(MPTCP_PM_ESTABLISHED);
|
2020-03-27 21:48:51 +00:00
|
|
|
mptcp_pm_nl_fully_established(msk);
|
2020-03-27 21:48:41 +00:00
|
|
|
}
|
|
|
|
if (pm->status & BIT(MPTCP_PM_SUBFLOW_ESTABLISHED)) {
|
|
|
|
pm->status &= ~BIT(MPTCP_PM_SUBFLOW_ESTABLISHED);
|
2020-03-27 21:48:51 +00:00
|
|
|
mptcp_pm_nl_subflow_established(msk);
|
2020-03-27 21:48:41 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
spin_unlock_bh(&msk->pm.lock);
|
|
|
|
release_sock(sk);
|
|
|
|
sock_put(sk);
|
2020-03-27 21:48:38 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
void mptcp_pm_data_init(struct mptcp_sock *msk)
|
|
|
|
{
|
|
|
|
msk->pm.add_addr_signaled = 0;
|
|
|
|
msk->pm.add_addr_accepted = 0;
|
|
|
|
msk->pm.local_addr_used = 0;
|
|
|
|
msk->pm.subflows = 0;
|
|
|
|
WRITE_ONCE(msk->pm.work_pending, false);
|
|
|
|
WRITE_ONCE(msk->pm.addr_signal, false);
|
|
|
|
WRITE_ONCE(msk->pm.accept_addr, false);
|
|
|
|
WRITE_ONCE(msk->pm.accept_subflow, false);
|
|
|
|
msk->pm.status = 0;
|
|
|
|
|
|
|
|
spin_lock_init(&msk->pm.lock);
|
|
|
|
INIT_WORK(&msk->pm.work, pm_worker);
|
2020-03-27 21:48:51 +00:00
|
|
|
|
|
|
|
mptcp_pm_nl_data_init(msk);
|
2020-03-27 21:48:38 +00:00
|
|
|
}
|
|
|
|
|
2020-03-27 21:48:41 +00:00
|
|
|
void mptcp_pm_close(struct mptcp_sock *msk)
|
|
|
|
{
|
|
|
|
if (cancel_work_sync(&msk->pm.work))
|
|
|
|
sock_put((struct sock *)msk);
|
|
|
|
}
|
|
|
|
|
2020-03-27 21:48:38 +00:00
|
|
|
void mptcp_pm_init(void)
|
|
|
|
{
|
|
|
|
pm_wq = alloc_workqueue("pm_wq", WQ_UNBOUND | WQ_MEM_RECLAIM, 8);
|
|
|
|
if (!pm_wq)
|
|
|
|
panic("Failed to allocate workqueue");
|
2020-03-27 21:48:51 +00:00
|
|
|
|
|
|
|
mptcp_pm_nl_init();
|
2020-03-27 21:48:38 +00:00
|
|
|
}
|