diff options
author | Johannes Berg <johannes@sipsolutions.net> | 2008-02-25 16:27:41 +0100 |
---|---|---|
committer | John W. Linville <linville@tuxdriver.com> | 2008-02-29 15:41:58 -0500 |
commit | 2485f7105f20f85c2dbebc67be6b2cb97175fa7e (patch) | |
tree | c8c620864bb220d8a299d7f45675334879eb742a | |
parent | 38c07b430b50172b803fe4c7f76cba580ba9931f (diff) | |
download | op-kernel-dev-2485f7105f20f85c2dbebc67be6b2cb97175fa7e.zip op-kernel-dev-2485f7105f20f85c2dbebc67be6b2cb97175fa7e.tar.gz |
mac80211: clarify use of TX status/RX callbacks
This patch clarifies the use of the irqsafe vs. non-irq-safe
functions and their respective locking requirements.
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
-rw-r--r-- | include/net/mac80211.h | 37 |
1 files changed, 34 insertions, 3 deletions
diff --git a/include/net/mac80211.h b/include/net/mac80211.h index cd4b1c1..7a80c39 100644 --- a/include/net/mac80211.h +++ b/include/net/mac80211.h @@ -38,7 +38,11 @@ * called in hardware interrupt context. The low-level driver must not call any * other functions in hardware interrupt context. If there is a need for such * call, the low-level driver should first ACK the interrupt and perform the - * IEEE 802.11 code call after this, e.g. from a scheduled workqueue function. + * IEEE 802.11 code call after this, e.g. from a scheduled workqueue or even + * tasklet function. + * + * NOTE: If the driver opts to use the _irqsafe() functions, it may not also + * use the non-irqsafe functions! */ /** @@ -1204,7 +1208,10 @@ void __ieee80211_rx(struct ieee80211_hw *hw, struct sk_buff *skb, * buffer in @skb must start with an IEEE 802.11 header or a radiotap * header if %RX_FLAG_RADIOTAP is set in the @status flags. * - * This function may not be called in IRQ context. + * This function may not be called in IRQ context. Calls to this function + * for a single hardware must be synchronized against each other. Calls + * to this function and ieee80211_rx_irqsafe() may not be mixed for a + * single hardware. * * @hw: the hardware this frame came in on * @skb: the buffer to receive, owned by mac80211 after this call @@ -1221,7 +1228,10 @@ static inline void ieee80211_rx(struct ieee80211_hw *hw, struct sk_buff *skb, * ieee80211_rx_irqsafe - receive frame * * Like ieee80211_rx() but can be called in IRQ context - * (internally defers to a workqueue.) + * (internally defers to a tasklet.) + * + * Calls to this function and ieee80211_rx() may not be mixed for a + * single hardware. * * @hw: the hardware this frame came in on * @skb: the buffer to receive, owned by mac80211 after this call @@ -1240,6 +1250,11 @@ void ieee80211_rx_irqsafe(struct ieee80211_hw *hw, * transmitted. It is permissible to not call this function for * multicast frames but this can affect statistics. * + * This function may not be called in IRQ context. Calls to this function + * for a single hardware must be synchronized against each other. Calls + * to this function and ieee80211_tx_status_irqsafe() may not be mixed + * for a single hardware. + * * @hw: the hardware the frame was transmitted by * @skb: the frame that was transmitted, owned by mac80211 after this call * @status: status information for this frame; the status pointer need not @@ -1249,6 +1264,22 @@ void ieee80211_rx_irqsafe(struct ieee80211_hw *hw, void ieee80211_tx_status(struct ieee80211_hw *hw, struct sk_buff *skb, struct ieee80211_tx_status *status); + +/** + * ieee80211_tx_status_irqsafe - irq-safe transmit status callback + * + * Like ieee80211_tx_status() but can be called in IRQ context + * (internally defers to a tasklet.) + * + * Calls to this function and ieee80211_tx_status() may not be mixed for a + * single hardware. + * + * @hw: the hardware the frame was transmitted by + * @skb: the frame that was transmitted, owned by mac80211 after this call + * @status: status information for this frame; the status pointer need not + * be valid after this function returns and is not freed by mac80211, + * it is recommended that it points to a stack area + */ void ieee80211_tx_status_irqsafe(struct ieee80211_hw *hw, struct sk_buff *skb, struct ieee80211_tx_status *status); |