linux.git/net/can/raw.c, branch v4.3

can: replace timestamp as unique skb attribute

2015-07-12T19:13:22+00:00

Commit 514ac99c64b "can: fix multiple delivery of a single CAN frame for
overlapping CAN filters" requires the skb->tstamp to be set to check for
identical CAN skbs.

Without timestamping to be required by user space applications this timestamp
was not generated which lead to commit 36c01245eb8 "can: fix loss of CAN frames
in raw_rcv" - which forces the timestamp to be set in all CAN related skbuffs
by introducing several __net_timestamp() calls.

This forces e.g. out of tree drivers which are not using alloc_can{,fd}_skb()
to add __net_timestamp() after skbuff creation to prevent the frame loss fixed
in mainline Linux.

This patch removes the timestamp dependency and uses an atomic counter to
create an unique identifier together with the skbuff pointer.

Btw: the new skbcnt element introduced in struct can_skb_priv has to be
initialized with zero in out-of-tree drivers which are not using
alloc_can{,fd}_skb() too.

Signed-off-by: Oliver Hartkopp 
Cc: linux-stable 
Signed-off-by: Marc Kleine-Budde

can: introduce new raw socket option to join the given CAN filters

2015-04-01T09:28:22+00:00

The CAN_RAW socket can set multiple CAN identifier specific filters that lead
to multiple filters in the af_can.c filter processing. These filters are
indenpendent from each other which leads to logical OR'ed filters when applied.

This socket option joines the given CAN filters in the way that only CAN frames
are passed to user space that matched *all* given CAN filters. The semantic for
the applied filters is therefore changed to a logical AND.

This is useful especially when the filterset is a combination of filters where
the CAN_INV_FILTER flag is set in order to notch single CAN IDs or CAN ID
ranges from the incoming traffic.

As the raw_rcv() function is executed from NET_RX softirq the introduced
variables are implemented as per-CPU variables to avoid extensive locking at
CAN frame reception time.

Signed-off-by: Oliver Hartkopp 
Signed-off-by: Marc Kleine-Budde

can: fix multiple delivery of a single CAN frame for overlapping CAN filters

2015-04-01T09:27:41+00:00

The CAN_RAW socket can set multiple CAN identifier specific filters that lead
to multiple filters in the af_can.c filter processing. These filters are
indenpendent from each other which leads to logical OR'ed filters when applied.

This patch makes sure that every CAN frame which is filtered for a specific
socket is only delivered once to the user space. This is independent from the
number of matching CAN filters of this socket.

As the raw_rcv() function is executed from NET_RX softirq the introduced
variables are implemented as per-CPU variables to avoid extensive locking at
CAN frame reception time.

Signed-off-by: Oliver Hartkopp 
Signed-off-by: Marc Kleine-Budde

net: Remove iocb argument from sendmsg and recvmsg

2015-03-02T18:06:31+00:00

After TIPC doesn't depend on iocb argument in its internal
implementations of sendmsg() and recvmsg() hooks defined in proto
structure, no any user is using iocb argument in them at all now.
Then we can drop the redundant iocb argument completely from kinds of
implementations of both sendmsg() and recvmsg() in the entire
networking stack.

Cc: Christoph Hellwig 
Suggested-by: Al Viro 
Signed-off-by: Ying Xue 
Signed-off-by: David S. Miller

net: use common macro for assering skb->cb[] available size in protocol families

2015-03-02T05:19:30+00:00

As part of an effort to move skb->dropcount to skb->cb[] use a common
macro in protocol families using skb->cb[] for ancillary data to
validate available room in skb->cb[].

Signed-off-by: Eyal Birger 
Signed-off-by: David S. Miller

can: eliminate banner[] variable and switch to pr_info()

2014-12-07T20:22:01+00:00

Several CAN modules use a design pattern with a banner[] variable at the
top which defines a string that is used once during init to print the
banner.  The string is also embedded with KERN_INFO which makes it
printk() specific.

Improve the code by eliminating the banner[] variable and moving the
string to where it is printed.  Then switch from printk(KERN_INFO to
pr_info() for the lines that were changed.

Signed-off-by: Jeremiah Mahler 
Acked-by: Oliver Hartkopp 
Signed-off-by: Marc Kleine-Budde

new helper: memcpy_to_msg()

2014-11-24T09:28:51+00:00

Signed-off-by: Al Viro

new helper: memcpy_from_msg()

2014-11-24T09:28:48+00:00

Signed-off-by: Al Viro

can: remove CAN FD compatibility for CAN 2.0 sockets

2014-03-03T13:29:52+00:00

In commit e2d265d3b587 (canfd: add support for CAN FD in CAN_RAW sockets)
CAN FD frames with a payload length up to 8 byte are passed to legacy
sockets where the CAN FD support was not enabled by the application.

After some discussions with developers at a fair this well meant feature
leads to confusion as no clean switch for CAN / CAN FD is provided to the
application programmer. Additionally a compatibility like this for legacy
CAN_RAW sockets requires some compatibility handling for the sending, e.g.
make CAN2.0 frames a CAN FD frame with BRS at transmission time (?!?).

This will become a mess when people start to develop applications with
real CAN FD hardware. This patch reverts the bad compatibility code
together with the documentation describing the removed feature.

Acked-by: Stephane Grosjean 
Signed-off-by: Oliver Hartkopp 
Signed-off-by: Marc Kleine-Budde

can: Propagate SO_PRIORITY of raw sockets to skbs

2014-01-29T19:23:23+00:00

This allows controlling certain queueing disciplines by setting the
socket's SO_PRIORITY option.

For example, with the default pfifo_fast queueing discipline, which
provides three priorities, socket priority TC_PRIO_CONTROL means
higher than default and TC_PRIO_BULK means lower than default.

Signed-off-by: Rostislav Lisovy 
Signed-off-by: Michal Sojka 
Acked-by: Oliver Hartkopp 
Signed-off-by: Marc Kleine-Budde