Commit 2b13db13 authored by Miquel Raynal's avatar Miquel Raynal Committed by Stefan Schmidt
Browse files

net: mac802154: Add a warning in the hot path 



We should never start a transmission after the queue has been stopped.

But because it might work we don't kill the function here but rather
warn loudly the user that something is wrong.

Set a flag when the queue should remain stopped. Reset this flag when
the queue actually gets restarded. Just check this value to know if a
transmission is legitimate, warn if it is not.

Turn the flags variable into an unsigned long to allow the use of atomic
helpers on it.

Signed-off-by: default avatarMiquel Raynal <miquel.raynal@bootlin.com>
Acked-by: default avatarAlexander Aring <aahringo@redhat.com>
Link: https://lore.kernel.org/r/20220519150516.443078-11-miquel.raynal@bootlin.com


Signed-off-by: default avatarStefan Schmidt <stefan@datenfreihafen.org>
parent ddd9ee7c

include/net/cfg802154.h

+4 −1
Original line number Diff line number Diff line
@@ -166,11 +166,14 @@ wpan_phy_cca_cmp(const struct wpan_phy_cca *a, const struct wpan_phy_cca *b) 
 *	level setting.

 * @WPAN_PHY_FLAG_CCA_MODE: Indicates that transceiver will support cca mode

 *	setting.

 * @WPAN_PHY_FLAG_STATE_QUEUE_STOPPED: Indicates that the transmit queue was

 *	temporarily stopped.

 */

enum wpan_phy_flags {

	WPAN_PHY_FLAG_TXPOWER		= BIT(1),

	WPAN_PHY_FLAG_CCA_ED_LEVEL	= BIT(2),

	WPAN_PHY_FLAG_CCA_MODE		= BIT(3),

	WPAN_PHY_FLAG_STATE_QUEUE_STOPPED = BIT(4),

};



struct wpan_phy {
@@ -182,7 +185,7 @@ struct wpan_phy { 
	 */

	const void *privid;



	u32 flags;

	unsigned long flags;



	/*

	 * This is a PIB according to 802.15.4-2011.

net/mac802154/tx.c

+15 −1
Original line number Diff line number Diff line
@@ -123,9 +123,13 @@ static int ieee802154_sync_queue(struct ieee802154_local *local) 


int ieee802154_sync_and_hold_queue(struct ieee802154_local *local)

{

	int ret;



	ieee802154_hold_queue(local);

	ret = ieee802154_sync_queue(local);

	set_bit(WPAN_PHY_FLAG_STATE_QUEUE_STOPPED, &local->phy->flags);



	return ieee802154_sync_queue(local);

	return ret;

}



int ieee802154_mlme_op_pre(struct ieee802154_local *local)
@@ -172,9 +176,19 @@ int ieee802154_mlme_tx_one(struct ieee802154_local *local, struct sk_buff *skb) 
	return ret;

}



static bool ieee802154_queue_is_stopped(struct ieee802154_local *local)

{

	return test_bit(WPAN_PHY_FLAG_STATE_QUEUE_STOPPED, &local->phy->flags);

}



static netdev_tx_t

ieee802154_hot_tx(struct ieee802154_local *local, struct sk_buff *skb)

{

	/* Warn if the net interface tries to transmit frames while the

	 * ieee802154 core assumes the queue is stopped.

	 */

	WARN_ON_ONCE(ieee802154_queue_is_stopped(local));



	return ieee802154_tx(local, skb);

}

net/mac802154/util.c

+1 −0
Original line number Diff line number Diff line
@@ -29,6 +29,7 @@ static void ieee802154_wake_queue(struct ieee802154_hw *hw) 
	struct ieee802154_sub_if_data *sdata;



	rcu_read_lock();

	clear_bit(WPAN_PHY_FLAG_STATE_QUEUE_STOPPED, &local->phy->flags);

	list_for_each_entry_rcu(sdata, &local->interfaces, list) {

		if (!sdata->dev)

			continue;