10 Commits

Author SHA1 Message Date
Arnd Bergmann
ca9ad549e4 carl9170: fix struct alignment conflict
Multiple structures in the carl9170 driver have alignment
impossible alignment constraints that gcc warns about when
building with 'make W=1':

drivers/net/wireless/ath/carl9170/fwcmd.h:243:2: warning: alignment 1 of 'union <anonymous>' is less than 4 [-Wpacked-not-aligned]
drivers/net/wireless/ath/carl9170/wlan.h:373:1: warning: alignment 1 of 'struct ar9170_rx_frame_single' is less than 2 [-Wpacked-not-aligned]

In the carl9170_cmd structure, multiple members that have an explicit
alignment requirement of four bytes are added into a union with explicit
byte alignment, but this in turn is part of a structure that also has
four-byte alignment.

In the wlan.h header, multiple structures contain a ieee80211_hdr member
that is required to be two-byte aligned to avoid alignmnet faults when
processing network headers, but all members are forced to be byte-aligned
using the __packed tag at the end of the struct definition.

In both cases, leaving out the packing does not change the internal
layout of the structure but changes the alignment constraint of the
structure itself.

Change all affected structures to only apply packing where it does
not violate the alignment requirement of the contained structure.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Christian Lamparter <chunkeey@gmail.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20210204162926.3262598-1-arnd@kernel.org
2021-02-09 09:24:20 +02:00
Gustavo A. R. Silva
103dc3dab2 carl9170: Replace zero-length array with flexible-array
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:

struct foo {
        int stuff;
        struct boo array[];
};

By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.

Also, notice that, dynamic memory allocations won't be affected by
this change:

"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]

sizeof(flexible-array-member) triggers a warning because flexible array
members have incomplete type[1]. There are some instances of code in
which the sizeof operator is being incorrectly/erroneously applied to
zero-length arrays and the result is zero. Such instances may be hiding
some bugs. So, this work (flexible-array member conversions) will also
help to get completely rid of those sorts of issues.

This issue was found with the help of Coccinelle.

[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 76497732932f ("cxgb3/l2t: Fix undefined behaviour")

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20200507151921.GA5083@embeddedor
2020-05-12 10:31:49 +03:00
Christian Lamparter
2f10e50e3d carl9170: import 1.9.9 firmware headers
Import new headers from my firmware branch:
<https://github.com/chunkeey/carl9170fw>

Signed-off-by: Christian Lamparter <chunkeey@googlemail.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
2016-03-07 14:11:09 +02:00
Christian Lamparter
5ae994d098 carl9170: import 1.9.7 firmware headers
Import new headers from my firmware branch:
<https://github.com/chunkeey/carl9170fw>

visit our wiki at:
<http://wireless.kernel.org/en/users/Drivers/carl9170.fw>

Signed-off-by: Christian Lamparter <chunkeey@googlemail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2013-01-07 15:16:51 -05:00
Christian Lamparter
f5e2289a14 carl9170: import updated firmware headers
Import new headers from our firmware branch:
git://git.kernel.org/pub/scm/linux/kernel/git/chr/carl9170fw.git

Signed-off-by: Christian Lamparter <chunkeey@googlemail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2011-08-24 14:41:42 -04:00
Christian Lamparter
85ee5122ab carl9170: import 1.9.4 firmware headers
This patch imports all shared header changes
from carl9170fw.git.

 * update copyright boilerplate

 * add some more strategic __aligned(4).

 * WoWLAN

Signed-off-by: Christian Lamparter <chunkeey@googlemail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2011-07-05 15:26:51 -04:00
Christian Lamparter
9e09b5c96c carl9170: update fw/hw headers
This patch syncs up the header files with
the project's main firmware carl9170fw.git.

Signed-off-by: Christian Lamparter <chunkeey@googlemail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2011-01-27 16:03:53 -05:00
Christian Lamparter
3f1240e4f4 carl9170: import hw/fw header updates
This patch imports all shared header changes
from carl9170fw.git.

 * add some strategic __aligned(4).
   This allows the compiler generate optimized code for
   architectures which can't access (unaligned/packed)
   data efficiently.
   ("ath9k_hw: optimize all descriptor access functions")

 * add a forgotten __CARL9170FW__ ifdef around
   a private firmware-internal struct.

 * GET_VAL macro helper
   Very useful for extracting data out of the
   bit-packed PHY registers.

 * cosmetic changes
   e.g.: _CCA_MINCCA_ to just _CCA_MIN_.

 * version bump 1.8.8.3 -> 1.9.0.

Signed-off-by: Christian Lamparter <chunkeey@googlemail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2010-11-15 13:25:29 -05:00
Christian Lamparter
5c89569194 carl9170: support firmware-based rx filter
The hardware rx-filter was essentially disabled, because
of a serve, yet unidentifiable problem with iwlagn.
Due to these circumstances the driver and mac80211 were
left with the job of filtering.

This is very unfortunate and has proven to be expensive
in terms of latency, memory and load.

Therefore the new 1.8.8.3 firmware introduces a flexible
filtering infrastructure which allows the driver to
offload some of the checks (FCS & PLCP crc check,
RA match, control frame filter, etc...) whenever possible.

Note:
This patch also includes all changes to the
shared headers files since the inclusion.

Signed-off-by: Christian Lamparter <chunkeey@googlemail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2010-10-05 13:35:21 -04:00
Christian Lamparter
aae9af605a carl9170: Register maps, tx/rx descriptor formats and eeprom layout
Signed-off-by: Christian Lamparter <chunkeey@googlemail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2010-09-14 16:03:41 -04:00