cfg80211/mac80211: allow management TX to not wait for ACK
For probe responses it can be useful to not wait for ACK to
avoid retransmissions if the station that sent the probe is
already on the next channel, so allow userspace to request
not caring about the ACK with a new nl80211 flag.
Since mac80211 needs to be updated for the new function
prototype anyway implement it right away -- it's just a
few lines of code.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/ath/ath6kl/cfg80211.c b/drivers/net/wireless/ath/ath6kl/cfg80211.c
index 3aff36b..daf444b 100644
--- a/drivers/net/wireless/ath/ath6kl/cfg80211.c
+++ b/drivers/net/wireless/ath/ath6kl/cfg80211.c
@@ -1732,7 +1732,8 @@
struct ieee80211_channel *chan, bool offchan,
enum nl80211_channel_type channel_type,
bool channel_type_valid, unsigned int wait,
- const u8 *buf, size_t len, bool no_cck, u64 *cookie)
+ const u8 *buf, size_t len, bool no_cck,
+ bool dont_wait_for_ack, u64 *cookie)
{
struct ath6kl *ar = ath6kl_priv(dev);
u32 id;
diff --git a/include/linux/nl80211.h b/include/linux/nl80211.h
index 09474ab..165e16f 100644
--- a/include/linux/nl80211.h
+++ b/include/linux/nl80211.h
@@ -1151,6 +1151,11 @@
* with support for the features listed in this attribute, see
* &enum nl80211_ap_sme_features.
*
+ * @NL80211_ATTR_DONT_WAIT_FOR_ACK: Used with %NL80211_CMD_FRAME, this tells
+ * the driver to not wait for an acknowledgement. Note that due to this,
+ * it will also not give a status callback nor return a cookie. This is
+ * mostly useful for probe responses to save airtime.
+ *
* @NL80211_ATTR_MAX: highest attribute number currently defined
* @__NL80211_ATTR_AFTER_LAST: internal use
*/
@@ -1381,6 +1386,8 @@
NL80211_ATTR_DEVICE_AP_SME,
+ NL80211_ATTR_DONT_WAIT_FOR_ACK,
+
/* add attributes here, update the policy in nl80211.c */
__NL80211_ATTR_AFTER_LAST,
diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h
index be3535f..00287bd 100644
--- a/include/net/cfg80211.h
+++ b/include/net/cfg80211.h
@@ -1588,7 +1588,7 @@
enum nl80211_channel_type channel_type,
bool channel_type_valid, unsigned int wait,
const u8 *buf, size_t len, bool no_cck,
- u64 *cookie);
+ bool dont_wait_for_ack, u64 *cookie);
int (*mgmt_tx_cancel_wait)(struct wiphy *wiphy,
struct net_device *dev,
u64 cookie);
diff --git a/net/mac80211/cfg.c b/net/mac80211/cfg.c
index e072fea..ab3258a 100644
--- a/net/mac80211/cfg.c
+++ b/net/mac80211/cfg.c
@@ -1936,7 +1936,7 @@
enum nl80211_channel_type channel_type,
bool channel_type_valid, unsigned int wait,
const u8 *buf, size_t len, bool no_cck,
- u64 *cookie)
+ bool dont_wait_for_ack, u64 *cookie)
{
struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
struct ieee80211_local *local = sdata->local;
@@ -1944,10 +1944,15 @@
struct sta_info *sta;
struct ieee80211_work *wk;
const struct ieee80211_mgmt *mgmt = (void *)buf;
- u32 flags = IEEE80211_TX_INTFL_NL80211_FRAME_TX |
- IEEE80211_TX_CTL_REQ_TX_STATUS;
+ u32 flags;
bool is_offchan = false;
+ if (dont_wait_for_ack)
+ flags = IEEE80211_TX_CTL_NO_ACK;
+ else
+ flags = IEEE80211_TX_INTFL_NL80211_FRAME_TX |
+ IEEE80211_TX_CTL_REQ_TX_STATUS;
+
/* Check that we are on the requested channel for transmission */
if (chan != local->tmp_channel &&
chan != local->oper_channel)
diff --git a/net/wireless/core.h b/net/wireless/core.h
index 4c6ff40..1c7d4df 100644
--- a/net/wireless/core.h
+++ b/net/wireless/core.h
@@ -378,7 +378,7 @@
enum nl80211_channel_type channel_type,
bool channel_type_valid, unsigned int wait,
const u8 *buf, size_t len, bool no_cck,
- u64 *cookie);
+ bool dont_wait_for_ack, u64 *cookie);
/* SME */
int __cfg80211_connect(struct cfg80211_registered_device *rdev,
diff --git a/net/wireless/mlme.c b/net/wireless/mlme.c
index 34891e0..6c1bafd 100644
--- a/net/wireless/mlme.c
+++ b/net/wireless/mlme.c
@@ -904,7 +904,7 @@
enum nl80211_channel_type channel_type,
bool channel_type_valid, unsigned int wait,
const u8 *buf, size_t len, bool no_cck,
- u64 *cookie)
+ bool dont_wait_for_ack, u64 *cookie)
{
struct wireless_dev *wdev = dev->ieee80211_ptr;
const struct ieee80211_mgmt *mgmt;
@@ -995,7 +995,8 @@
/* Transmit the Action frame as requested by user space */
return rdev->ops->mgmt_tx(&rdev->wiphy, dev, chan, offchan,
channel_type, channel_type_valid,
- wait, buf, len, no_cck, cookie);
+ wait, buf, len, no_cck, dont_wait_for_ack,
+ cookie);
}
bool cfg80211_rx_mgmt(struct net_device *dev, int freq, const u8 *buf,
diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index 5b65906..0ef0941 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -196,6 +196,7 @@
[NL80211_ATTR_TDLS_OPERATION] = { .type = NLA_U8 },
[NL80211_ATTR_TDLS_SUPPORT] = { .type = NLA_FLAG },
[NL80211_ATTR_TDLS_EXTERNAL_SETUP] = { .type = NLA_FLAG },
+ [NL80211_ATTR_DONT_WAIT_FOR_ACK] = { .type = NLA_FLAG },
};
/* policy for the key attributes */
@@ -5282,10 +5283,11 @@
int err;
void *hdr;
u64 cookie;
- struct sk_buff *msg;
+ struct sk_buff *msg = NULL;
unsigned int wait = 0;
- bool offchan;
- bool no_cck;
+ bool offchan, no_cck, dont_wait_for_ack;
+
+ dont_wait_for_ack = info->attrs[NL80211_ATTR_DONT_WAIT_FOR_ACK];
if (!info->attrs[NL80211_ATTR_FRAME] ||
!info->attrs[NL80211_ATTR_WIPHY_FREQ])
@@ -5329,29 +5331,36 @@
if (chan == NULL)
return -EINVAL;
- msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
- if (!msg)
- return -ENOMEM;
+ if (!dont_wait_for_ack) {
+ msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
+ if (!msg)
+ return -ENOMEM;
- hdr = nl80211hdr_put(msg, info->snd_pid, info->snd_seq, 0,
- NL80211_CMD_FRAME);
+ hdr = nl80211hdr_put(msg, info->snd_pid, info->snd_seq, 0,
+ NL80211_CMD_FRAME);
- if (IS_ERR(hdr)) {
- err = PTR_ERR(hdr);
- goto free_msg;
+ if (IS_ERR(hdr)) {
+ err = PTR_ERR(hdr);
+ goto free_msg;
+ }
}
+
err = cfg80211_mlme_mgmt_tx(rdev, dev, chan, offchan, channel_type,
channel_type_valid, wait,
nla_data(info->attrs[NL80211_ATTR_FRAME]),
nla_len(info->attrs[NL80211_ATTR_FRAME]),
- no_cck, &cookie);
+ no_cck, dont_wait_for_ack, &cookie);
if (err)
goto free_msg;
- NLA_PUT_U64(msg, NL80211_ATTR_COOKIE, cookie);
+ if (msg) {
+ NLA_PUT_U64(msg, NL80211_ATTR_COOKIE, cookie);
- genlmsg_end(msg, hdr);
- return genlmsg_reply(msg, info);
+ genlmsg_end(msg, hdr);
+ return genlmsg_reply(msg, info);
+ }
+
+ return 0;
nla_put_failure:
err = -ENOBUFS;