1 files changed, 71 insertions, 63 deletions

diff --git a/net/mptcp/pm.c b/net/mptcp/pm.c
index 977d9c8b1453..e19e1525ecbb 100644
--- a/net/mptcp/pm.c
+++ b/net/mptcp/pm.c
@@ -10,28 +10,37 @@
 #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)
+			   const struct mptcp_addr_info *addr,
+			   bool echo)
 {
 	pr_debug("msk=%p, local_id=%d", msk, addr->id);
 
 	msk->pm.local = *addr;
-	WRITE_ONCE(msk->pm.addr_signal, true);
+	WRITE_ONCE(msk->pm.add_addr_echo, echo);
+	WRITE_ONCE(msk->pm.add_addr_signal, true);
 	return 0;
 }
 
 int mptcp_pm_remove_addr(struct mptcp_sock *msk, u8 local_id)
 {
-	return -ENOTSUPP;
+	pr_debug("msk=%p, local_id=%d", msk, local_id);
+
+	msk->pm.rm_id = local_id;
+	WRITE_ONCE(msk->pm.rm_addr_signal, true);
+	return 0;
 }
 
-int mptcp_pm_remove_subflow(struct mptcp_sock *msk, u8 remote_id)
+int mptcp_pm_remove_subflow(struct mptcp_sock *msk, u8 local_id)
 {
-	return -ENOTSUPP;
+	pr_debug("msk=%p, local_id=%d", msk, local_id);
+
+	spin_lock_bh(&msk->pm.lock);
+	mptcp_pm_nl_rm_subflow_received(msk, local_id);
+	spin_unlock_bh(&msk->pm.lock);
+	return 0;
 }
 
 /* path manager event handlers */
@@ -48,7 +57,7 @@ void mptcp_pm_new_connection(struct mptcp_sock *msk, int server_side)
 bool mptcp_pm_allow_new_subflow(struct mptcp_sock *msk)
 {
 	struct mptcp_pm_data *pm = &msk->pm;
-	int ret;
+	int ret = 0;
 
 	pr_debug("msk=%p subflows=%d max=%d allow=%d", msk, pm->subflows,
 		 pm->subflows_max, READ_ONCE(pm->accept_subflow));
@@ -58,9 +67,11 @@ bool mptcp_pm_allow_new_subflow(struct mptcp_sock *msk)
 		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);
+	if (READ_ONCE(pm->accept_subflow)) {
+		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;
@@ -78,7 +89,7 @@ static bool mptcp_pm_schedule_work(struct mptcp_sock *msk,
 		return false;
 
 	msk->pm.status |= BIT(new_status);
-	if (queue_work(pm_wq, &msk->pm.work))
+	if (schedule_work(&msk->work))
 		sock_hold((struct sock *)msk);
 	return true;
 }
@@ -137,38 +148,48 @@ void mptcp_pm_add_addr_received(struct mptcp_sock *msk,
 	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))
+	if (!READ_ONCE(pm->accept_addr))
+		mptcp_pm_announce_addr(msk, addr, true);
+	else if (mptcp_pm_schedule_work(msk, MPTCP_PM_ADD_ADDR_RECEIVED))
 		pm->remote = *addr;
 
 	spin_unlock_bh(&pm->lock);
 }
 
+void mptcp_pm_rm_addr_received(struct mptcp_sock *msk, u8 rm_id)
+{
+	struct mptcp_pm_data *pm = &msk->pm;
+
+	pr_debug("msk=%p remote_id=%d", msk, rm_id);
+
+	spin_lock_bh(&pm->lock);
+	mptcp_pm_schedule_work(msk, MPTCP_PM_RM_ADDR_RECEIVED);
+	pm->rm_id = rm_id;
+	spin_unlock_bh(&pm->lock);
+}
+
 /* path manager helpers */
 
-bool mptcp_pm_addr_signal(struct mptcp_sock *msk, unsigned int remaining,
-			  struct mptcp_addr_info *saddr)
+bool mptcp_pm_add_addr_signal(struct mptcp_sock *msk, unsigned int remaining,
+			      struct mptcp_addr_info *saddr, bool *echo)
 {
 	int ret = false;
 
 	spin_lock_bh(&msk->pm.lock);
 
 	/* double check after the lock is acquired */
-	if (!mptcp_pm_should_signal(msk))
+	if (!mptcp_pm_should_add_signal(msk))
 		goto out_unlock;
 
-	if (remaining < mptcp_add_addr_len(msk->pm.local.family))
+	*echo = READ_ONCE(msk->pm.add_addr_echo);
+
+	if (remaining < mptcp_add_addr_len(msk->pm.local.family, *echo))
 		goto out_unlock;
 
 	*saddr = msk->pm.local;
-	WRITE_ONCE(msk->pm.addr_signal, false);
+	WRITE_ONCE(msk->pm.add_addr_signal, false);
 	ret = true;
 
 out_unlock:
@@ -176,38 +197,32 @@ out_unlock:
 	return ret;
 }
 
-int mptcp_pm_get_local_id(struct mptcp_sock *msk, struct sock_common *skc)
+bool mptcp_pm_rm_addr_signal(struct mptcp_sock *msk, unsigned int remaining,
+			     u8 *rm_id)
 {
-	return mptcp_pm_nl_get_local_id(msk, skc);
-}
-
-static void pm_worker(struct work_struct *work)
-{
-	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;
+	int ret = false;
 
-	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);
-		mptcp_pm_nl_add_addr_received(msk);
-	}
-	if (pm->status & BIT(MPTCP_PM_ESTABLISHED)) {
-		pm->status &= ~BIT(MPTCP_PM_ESTABLISHED);
-		mptcp_pm_nl_fully_established(msk);
-	}
-	if (pm->status & BIT(MPTCP_PM_SUBFLOW_ESTABLISHED)) {
-		pm->status &= ~BIT(MPTCP_PM_SUBFLOW_ESTABLISHED);
-		mptcp_pm_nl_subflow_established(msk);
-	}
+	/* double check after the lock is acquired */
+	if (!mptcp_pm_should_rm_signal(msk))
+		goto out_unlock;
+
+	if (remaining < TCPOLEN_MPTCP_RM_ADDR_BASE)
+		goto out_unlock;
+
+	*rm_id = msk->pm.rm_id;
+	WRITE_ONCE(msk->pm.rm_addr_signal, false);
+	ret = true;
 
+out_unlock:
 	spin_unlock_bh(&msk->pm.lock);
-	release_sock(sk);
-	sock_put(sk);
+	return ret;
+}
+
+int mptcp_pm_get_local_id(struct mptcp_sock *msk, struct sock_common *skc)
+{
+	return mptcp_pm_nl_get_local_id(msk, skc);
 }
 
 void mptcp_pm_data_init(struct mptcp_sock *msk)
@@ -216,29 +231,22 @@ void mptcp_pm_data_init(struct mptcp_sock *msk)
 	msk->pm.add_addr_accepted = 0;
 	msk->pm.local_addr_used = 0;
 	msk->pm.subflows = 0;
+	msk->pm.rm_id = 0;
 	WRITE_ONCE(msk->pm.work_pending, false);
-	WRITE_ONCE(msk->pm.addr_signal, false);
+	WRITE_ONCE(msk->pm.add_addr_signal, false);
+	WRITE_ONCE(msk->pm.rm_addr_signal, false);
 	WRITE_ONCE(msk->pm.accept_addr, false);
 	WRITE_ONCE(msk->pm.accept_subflow, false);
+	WRITE_ONCE(msk->pm.add_addr_echo, false);
 	msk->pm.status = 0;
 
 	spin_lock_init(&msk->pm.lock);
-	INIT_WORK(&msk->pm.work, pm_worker);
+	INIT_LIST_HEAD(&msk->pm.anno_list);
 
 	mptcp_pm_nl_data_init(msk);
 }
 
-void mptcp_pm_close(struct mptcp_sock *msk)
+void __init mptcp_pm_init(void)
 {
-	if (cancel_work_sync(&msk->pm.work))
-		sock_put((struct sock *)msk);
-}
-
-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");
-
 	mptcp_pm_nl_init();
 }