It seems like a historic accident that these return unsigned char *,
and in many places that means casts are required, more often than not.
Make these functions return void * and remove all the casts across
the tree, adding a (u8 *) cast only where the unsigned char pointer
was used directly, all done with the following spatch:
@@
expression SKB, LEN;
typedef u8;
identifier fn = { skb_push, __skb_push, skb_push_rcsum };
@@
- *(fn(SKB, LEN))
+ *(u8 *)fn(SKB, LEN)
@@
expression E, SKB, LEN;
identifier fn = { skb_push, __skb_push, skb_push_rcsum };
type T;
@@
- E = ((T *)(fn(SKB, LEN)))
+ E = fn(SKB, LEN)
@@
expression SKB, LEN;
identifier fn = { skb_push, __skb_push, skb_push_rcsum };
@@
- fn(SKB, LEN)[0]
+ *(u8 *)fn(SKB, LEN)
Note that the last part there converts from push(...)[0] to the
more idiomatic *(u8 *)push(...).
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This enum is already perfectly aliased to enum nl80211_band, and
the only reason for it is that we get IEEE80211_NUM_BANDS out of
it. There's no really good reason to not declare the number of
bands in nl80211 though, so do that and remove the cfg80211 one.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
According to RCU_INIT_POINTER()'s block comment 3.a, it can be used if
"3. The referenced data structure has already been exposed to readers either
at compile time or via rcu_assign_pointer() -and-
a. You have not made -any- reader-visible changes to this structure since
then".
This case fulfills the conditions above because between the rcu_dereference()
call (cvif = rcu_dereference(ar->beacon_iter);) and the rcu_assign_pointer()
call there is no update of the "cvif" variable.
Therefore, this patch makes the replacement.
The following Coccinelle semantic patch was used:
@@
identifier v;
@@
v = rcu_dereference(...);
... when != rcu_dereference(...);
when != v = ...;
when != (<+...v...+>)++;
when != \(memcpy\|memset\)(...);
(
- rcu_assign_pointer
+ RCU_INIT_POINTER
(..., v);
|
if(...) {
... when != v = ...;
- rcu_assign_pointer
+ RCU_INIT_POINTER
(..., v);
... when any
}
)
Because there are cases where between a “rcu_dereference()” call and a
“rcu_assign_pointer()” call might be updates of the value that interests us,
the Coccinelle semantic patch ignores them and replaces with
"RCU_INIT_POINTER()" only when the update is not happening.
Signed-off-by: Andreea-Cristina Bernat <bernat.ada@gmail.com>
Acked-by: Christian Lamparter <chunkeey@googlemail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
None of these files are actually using any __init type directives
and hence don't need to include <linux/init.h>. Most are just a
left over from __devinit and __cpuinit removal, or simply due to
code getting copied from one driver to the next.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Acked-by: Larry Finger <Larry.Finger@lwfinger.net>
Acked-by: Christian Lamparter <chunkeey@googlemail.com>
Acked-by: Gertjan van Wingerde <gwingerde@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
With the new rate control API, the driver can now apply the
tx rate to outgoing frames just before they are uploaded to
the device. This is important because the rate control can
now react to fading or improving links a bit sooner.
Also, the driver no longer needs to sort the outgoing frames
for sample attempts (which affected the size of A-MPDUs and
the throughput of the link). For aggregated data frames, the
driver (and rate control) needs only to calculate and apply
a single set of tx rates to every subframe of the whole
aggregate.
Signed-off-by: Christian Lamparter <chunkeey@googlemail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
With "mac80211/minstrel_ht: add support for using CCK rates"
minstrel_ht selects legacy CCK rates as viable rates for
outgoing frames which might be sent as part of an A-MPDU
[IEEE80211_TX_CTL_AMPDU is set].
This behavior triggered the following WARN_ON in the driver:
> WARNING: at carl9170/tx.c:995 carl9170_op_tx+0x1dd/0x6fd
The driver assumed that the rate control algorithm made a
mistake and dropped the frame.
This patch removes the noisy warning altogether and allows
said A-MPDU frames with CCK sample and/or fallback rates to
be transmitted seamlessly.
Signed-off-by: Christian Lamparter <chunkeey@googlemail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
This patch moves parts of carl9170_update_beacon
into separate subroutines, so the parts become
more manageable.
Signed-off-by: Christian Lamparter <chunkeey@googlemail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Dan Carpenter reported that smatch detected a potential
problem with the code [1]:
drivers/net/wireless/ath/carl9170/tx.c:1488 carl9170_op_tx()
error: we previously assumed 'sta' could be null (see line 1482)
drivers/net/wireless/ath/carl9170/tx.c
1482 if (sta) {
^^^^^ New check.
[...]
1485 }
1487 if (info->flags & IEEE80211_TX_CTL_AMPDU) {
1488 run = carl9170_tx_ampdu_queue(ar, sta, skb);
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Old dereference of "sta" inside the call to carl9170_tx_ampdu_queue().
A range of solutions have been discussed in [2] and
we agreed on the following: "
> we might as well add a comment to carl9170_tx_ampdu_queue
> and explain the situation [in a way that's obvious to a
> human reader]. This way we can save the "if"... which is
> a small win since carl9170_op_tx is sort of a hot-path.
Putting a comment there is fine. Without the comment
it's easy for a human reader to get confused why the
check is there. So long as humans can read the code,
that's all that matters."
[1] <http://www.spinics.net/lists/linux-wireless/msg94526.html>
[2] <http://www.spinics.net/lists/linux-kernel-janitors/msg14953.html>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Christian Lamparter <chunkeey@googlemail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Remove the control.sta pointer from ieee80211_tx_info to free up
sufficient space in the TX skb control buffer for the upcoming
Transmit Power Control (TPC).
Instead, the pointer is now on the stack in a new control struct
that is passed as a function parameter to the drivers' tx method.
Signed-off-by: Thomas Huehn <thomas@net.t-labs.tu-berlin.de>
Signed-off-by: Alina Friedrichsen <x-alina@gmx.net>
Signed-off-by: Felix Fietkau <nbd@openwrt.org>
[reworded commit message]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
This patch adds an alternative tx status path
for BlockAck Requests as the hardware doesn't
recognize that a BlockAck Requests is usually
acked with a BlockAck and not a legacy ACK.
Without this patch, the stack would constantly
resent old and stale BARs. So, depending on the
receiver stack, this could lead to:
- "stuck" ba sessions and package loss, as the
stale BAR would reset the sequence each time.
- lots of reorder releases.
- ...
Reported-by: Sean Patrick Santos <quantheory@gmail.com>
Reported-by: Mikołaj Kuligowski <mikolaj.q@wp.pl>
Reported-by: Per-Erik Westerberg <per-erik.westerberg@bredband.net>
Signed-off-by: Christian Lamparter <chunkeey@googlemail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
IEEE80211_TX_MAX_RATES can be reduced from 5 to 4 as there
is no current hardware supporting a rate chain with 5 multi
rate stages (mrr), so 4 mrr stages are sufficient.
The memory that is freed within the ieee80211_tx_info struct
will be used in the upcoming Transmission Power Control (TPC)
implementation.
Suggested-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: Thomas Huehn <thomas@net.t-labs.tu-berlin.de>
[reword commit message]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
That commit intended for 3.4 renamed IEEE80211_TX_CTL_POLL_RESPONSE as
IEEE80211_TX_CTL_NO_PS_BUFFER. Meanwhile, "carl9170: fix frame delivery
if sta is in powersave mode" added a reference to
IEEE80211_TX_CTL_POLL_RESPONSE in the fixes stream for 3.3. This simple
patch fixes that merge boo-boo.
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Nicolas Cavallari discovered that carl9170 has some
serious problems delivering data to sleeping stations.
It turns out that the driver was not honoring two
important flags (IEEE80211_TX_CTL_POLL_RESPONSE and
IEEE80211_TX_CTL_CLEAR_PS_FILT) which are set on
frames that should be sent although the receiving
station is still in powersave mode.
Cc: stable <stable@vger.kernel.org>
Reported-by: Nicolas Cavallari <Nicolas.Cavallari@lri.fr>
Signed-off-by: Christian Lamparter <chunkeey@googlemail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
On Access Point mode, when transmitting a packet, if the destination
station is in powersave mode, we abort transmitting the packet to the
device queue, but we do not reclaim the allocated memory. Given enough
packets, we can go in a state where there is no packet on the device
queue, but we think the device has no memory left, so no packet gets
transmitted, connections breaks and the AP stops working.
This undo the allocation done in the TX path when the station is in
power-save mode.
Signed-off-by: Nicolas Cavallari <cavallar@lri.fr>
Acked-by: Christian Lamparter <chunkeey@googlemail.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
This patch implements a simple way of reducing the
output power of the device by a configurable upper
limit.
Requested-by: Harshal Chhaya <harshal@gmail.com>
Signed-off-by: Christian Lamparter <chunkeey@googlemail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
In the past, it was fine to simply call
dev_kfree_skb when it was impossible to
transmit a skb. However, with the new
tx status API:
"mac80211: implement wifi TX status"
Every loose skb needs to be handed back
to mac80211.
Signed-off-by: Christian Lamparter <chunkeey@googlemail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Previously the driver did not care if TX_CTL_REQ_TX_STATUS
was set on aggregated frames or not and it would silently
drop successfully sent frames if possible [much like:
"no news is good news!"].
But, TX_CTL_REQ_TX_STATUS was invented for a reason and
no tx status report should ever be dropped if it is set.
Reported-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Christian Lamparter <chunkeey@googlemail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Harshal Chhaya discovered during network tests, that
several of his clients dropped-off the network. The
captured packets shows that the beacons sent by the
AP are at a much lower power than the other data
packets.
The reason for this mishap: The driver never updated
the beacon phy register, so all beacons were always
sent at the lowest power.
Reference: http://marc.info/?l=linux-wireless&m=131067225105801
Reported-by: Harshal Chhaya <harshal@gmail.com>
Signed-off-by: Christian Lamparter <chunkeey@googlemail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
tx.c: In function ‘carl9170_tx_accounting_free’:
tx.c:159:28: warning: variable ‘txinfo’ set but not used
tx.c: In function ‘carl9170_tx_status_process_ampdu’:
tx.c:383:27: warning: variable ‘ar_info’ set but not used
tx.c: In function ‘__carl9170_tx_process_status’:
tx.c:626:27: warning: variable ‘arinfo’ set but not used
tx.c: In function ‘carl9170_tx_ampdu_queue’:
tx.c:1324:15: warning: variable ‘max’ set but not used
Signed-off-by: Christian Lamparter <chunkeey@googlemail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Using the ieee80211_sta_block allows the PS code
to handle awake->doze->awake transitions of our
clients in a race-free manner.
Signed-off-by: Christian Lamparter <chunkeey@googlemail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Some clients seem to rely upon the reception of BlockAckReqs to flush
their rx reorder buffer. In order to fix aggregation for these clients
carl9170 should set IEEE80211_TX_STAT_AMPDU_NO_BACK to generate a
BlockAckReq if the transmission of an AMPDU subframe fails.
This fixes aggregation problems with Intel 5100 Windows STAs (and maybe
others as well).
Signed-off-by: Christian Lamparter <chunkeey@googlemail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
The return value of the tx operation is commonly
misused by drivers, leading to errors. All drivers
will drop frames if they fail to TX the frame, and
they must also properly manage the queues (if they
didn't, mac80211 would already warn).
Removing the ability for drivers to return a BUSY
value also allows significant cleanups of the TX
TX handling code in mac80211.
Note that this also fixes a bug in ath9k_htc, the
old "return -1" there was wrong.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Tested-by: Sedat Dilek <sedat.dilek@googlemail.com> [ath5k]
Acked-by: Gertjan van Wingerde <gwingerde@gmail.com> [rt2x00]
Acked-by: Larry Finger <Larry.Finger@lwfinger.net> [b43, rtl8187, rtlwifi]
Acked-by: Luciano Coelho <coelho@ti.com> [wl12xx]
Signed-off-by: John W. Linville <linville@tuxdriver.com>
"mac80211 will properly assign sequence numbers to QoS-data
frames but cannot do so correctly for non-QoS-data and
management frames because beacons need them from that counter
as well and mac80211 cannot guarantee proper sequencing."
Signed-off-by: Christian Lamparter <chunkeey@googlemail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
commit: "carl9170: revamp carl9170_tx_prepare"
introduced a peculiar bug that would only show
up if the the module parameter noht is set to 1.
Then all outbound voice, video and background
frames would each invoke a (bogus) RTS/CTS
handshake.
Signed-off-by: Christian Lamparter <chunkeey@googlemail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
The commit: "carl9170: tx path review" introduced a regression.
gcc (with -Winit-self):
tx.c:1264: warning: ‘super’ is used uninitialized in this function
Signed-off-by: Christian Lamparter <chunkeey@googlemail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
This patch fixes a few shortcomings in the tx path.
* move temp. ampdu_[ack]_len out of txinfo->pad.
* fix WARN_ON from tx.c:line 300 when tx_ampdu_queue
fails to queue the frame.
* In tx_prepare, we already have a local pointer
to the station's ieee80211_sta struct.
* remove a second !sta check, tx_prepare already takes
care of that.
Signed-off-by: Christian Lamparter <chunkeey@googlemail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
This patch fixes a possible lengthy stall if the device
is operating as an experimental 11n AP and an STA
[during heavy txrx action] suddenly signalized to go
off-channel (old NetworkManager), or (sleep - which is
unlikely, because then it wouldn't be *active* at all!?).
Because the driver has to manage the BA Window, the
sudden PSM transition can leave active uplink BA
sessions to the STA in a bad state and a proper
cleanup is needed.
Signed-off-by: Christian Lamparter <chunkeey@googlemail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
David Miller complained about the driver's excessive use
of variables in __packed structs. While I did not fully
agree with his sole "performance" argument on all accounts.
I do see some room for improvement in hot-paths on
architectures without an efficient access to unaligned
elements.
This first patch (dare I say?) optimizes an important tx
hot-path in the driver: carl9170_tx_prepare.
Signed-off-by: Christian Lamparter <chunkeey@googlemail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
This patch removes some cruft, which survived
the RFC review phase.
Originally, carl9170_tx_ampdu_queue erroneously
dropped a lot of frames. As a result the ampdu
scheduler bogged down quite frequently and the
affected BA session timed out.
However this bug has been fixed and the WA and
its debugfs counter is no longer useful.
Signed-off-by: Christian Lamparter <chunkeey@googlemail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Johannes Berg