Contrary to common expectations for an "int" return, these functions
return only a positive value -- if used correctly they cannot even
return 0 because the message header will necessarily be in the skb.
This makes the very common pattern of
if (genlmsg_end(...) < 0) { ... }
be a whole bunch of dead code. Many places also simply do
return nlmsg_end(...);
and the caller is expected to deal with it.
This also commonly (at least for me) causes errors, because it is very
common to write
if (my_function(...))
/* error condition */
and if my_function() does "return nlmsg_end()" this is of course wrong.
Additionally, there's not a single place in the kernel that actually
needs the message length returned, and if anyone needs it later then
it'll be very easy to just use skb->len there.
Remove this, and make the functions void. This removes a bunch of dead
code as described above. The patch adds lines because I did
- return nlmsg_end(...);
+ nlmsg_end(...);
+ return 0;
I could have preserved all the function's return values by returning
skb->len, but instead I've audited all the places calling the affected
functions and found that none cared. A few places actually compared
the return value with <= 0 in dump functionality, but that could just
be changed to < 0 with no change in behaviour, so I opted for the more
efficient version.
One instance of the error I've made numerous times now is also present
in net/phonet/pn_netlink.c in the route_dumpit() function - it didn't
check for <0 or <=0 and thus broke out of the loop every single time.
I've preserved this since it will (I think) have caused the messages to
userspace to be formatted differently with just a single message for
every SKB returned to userspace. It's possible that this isn't needed
for the tools that actually use this, but I don't even know what they
are so couldn't test that changing this behaviour would be acceptable.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds support for setting cca parameters via nl802154.
Signed-off-by: Alexander Aring <alex.aring@gmail.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The current cca setting handle is a driver specific call. We need to
introduce some 802.15.4 specific layer and mapping 802.15.4 cca modes to
driver specific ones inside the 802.15.4 driver. This patch will add
such 802.15.4 layer and mapping the cca settings to driver specific ones.
Signed-off-by: Alexander Aring <alex.aring@gmail.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
This patch changes the byteorder handling for short and panid handling.
We now except to get little endian in nl802154 for these attributes.
Signed-off-by: Alexander Aring <alex.aring@gmail.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
This patch moves the 802.15.4 constraints WPAN_NUM_ defines into
"net/ieee802154.h" which should contain all necessary 802.15.4 related
information. Also rename these defines to a common name which is
IEEE802154_MAX_CHANNEL and IEEE802154_MAX_PAGE.
Signed-off-by: Alexander Aring <alex.aring@gmail.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
This patch adds support for deleting a wpan interface via nl802154.
Signed-off-by: Alexander Aring <alex.aring@gmail.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
This patch adds support for setting an extended address while
registration a new interface. If ieee802154_is_valid_extended_addr
getting as parameter and invalid extended address then the perm address
is fallback. This is useful to make some default handling while for
example default registration of a wpan interface while phy registration.
Signed-off-by: Alexander Aring <alex.aring@gmail.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
This patch adds a new nl802154 command for adding a new interface
according to a wpan phy via nl802154.
Signed-off-by: Alexander Aring <alex.aring@gmail.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
This patch adds support for setting listen before transmit mode via
nl802154 framework.
Signed-off-by: Alexander Aring <alex.aring@gmail.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
This patch add support for setting mac frame retries setting via
nl802154 framework.
Signed-off-by: Alexander Aring <alex.aring@gmail.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
This patch add support for max csma backoffs setting via nl802154
framework.
Signed-off-by: Alexander Aring <alex.aring@gmail.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
This patch adds support for setting backoff exponents via nl802154
framework.
Signed-off-by: Alexander Aring <alex.aring@gmail.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
This patch adds support for setting short address via nl802154 framework.
Also added a comment because a 0xffff seems to be valid address that we
don't have a short address. This is a valid setting but we need
more checks in upper layers to don't allow this address as source address.
Also the current netlink interface doesn't allow to set the short_addr
to 0xffff. Same for the 0xfffe short address which describes a not
allocated short address.
Signed-off-by: Alexander Aring <alex.aring@gmail.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
This patch adds support for setting pan_id via nl802154 framework.
Adding a comment because setting 0xffff as pan_id seems to be valid
setting. The pan_id 0xffff as source pan is invalid. I am not sure now
about this setting but for the current netlink interface this is an
invalid setting, so we do the same now. Maybe we need to change that
when we have coordinator support and association support.
Signed-off-by: Alexander Aring <alex.aring@gmail.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
This patch adds page and channel setting support to nl802154 framework.
Signed-off-by: Alexander Aring <alex.aring@gmail.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
This patch adds support for wpan_dev dump via nl802154 framework.
Signed-off-by: Alexander Aring <alex.aring@gmail.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
This patch adds support for dumping wpan_phy attributes via nl802154.
Signed-off-by: Alexander Aring <alex.aring@gmail.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
This patch adds a basic nl802154 framework. Most of this code was
grabbed from nl80211 framework.
Signed-off-by: Alexander Aring <alex.aring@gmail.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Johannes Berg