kernel/linux.git/net/lapb, branch v6.12.80

net: lapb: Use list_for_each_entry() to simplify code in lapb_iface.c

2021-06-08T23:31:25+00:00

Convert list_for_each() to list_for_each_entry() where applicable. This simplifies the code. Reported-by: Hulk Robot Signed-off-by: Wang Hai Signed-off-by: David S. Miller

net: lapb: Make "lapb_t1timer_running" able to detect an already running timer

2021-03-23T21:14:50+00:00

Problem: The "lapb_t1timer_running" function in "lapb_timer.c" is used in only one place: in the "lapb_kick" function in "lapb_out.c". "lapb_kick" calls "lapb_t1timer_running" to check if the timer is already pending, and if it is not, schedule it to run. However, if the timer has already fired and is running, and is waiting to get the "lapb->lock" lock, "lapb_t1timer_running" will not detect this, and "lapb_kick" will then schedule a new timer. The old timer will then abort when it sees a new timer pending. I think this is not right. The purpose of "lapb_kick" should be ensuring that the actual work of the timer function is scheduled to be done. If the timer function is already running but waiting for the lock, "lapb_kick" should not abort and reschedule it. Changes made: I added a new field "t1timer_running" in "struct lapb_cb" for "lapb_t1timer_running" to use. "t1timer_running" will accurately reflect whether the actual work of the timer is pending. If the timer has fired but is still waiting for the lock, "t1timer_running" will still correctly reflect whether the actual work is waiting to be done. The old "t1timer_stop" field, whose only responsibility is to ask a timer (that is already running but waiting for the lock) to abort, is no longer needed, because the new "t1timer_running" field can fully take over its responsibility. Therefore "t1timer_stop" is deleted. "t1timer_running" is not simply a negation of the old "t1timer_stop". At the end of the timer function, if it does not reschedule itself, "t1timer_running" is set to false to indicate that the timer is stopped. For consistency of the code, I also added "t2timer_running" and deleted "t2timer_stop". Signed-off-by: Xie He Signed-off-by: David S. Miller

net: lapb: Copy the skb before sending a packet

2021-02-02T16:40:48+00:00

When sending a packet, we will prepend it with an LAPB header. This modifies the shared parts of a cloned skb, so we should copy the skb rather than just clone it, before we prepend the header. In "Documentation/networking/driver.rst" (the 2nd point), it states that drivers shouldn't modify the shared parts of a cloned skb when transmitting. The "dev_queue_xmit_nit" function in "net/core/dev.c", which is called when an skb is being sent, clones the skb and sents the clone to AF_PACKET sockets. Because the LAPB drivers first remove a 1-byte pseudo-header before handing over the skb to us, if we don't copy the skb before prepending the LAPB header, the first byte of the packets received on AF_PACKET sockets can be corrupted. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Xie He Acked-by: Martin Schiller Link: https://lore.kernel.org/r/20210201055706.415842-1-xie.he.0141@gmail.com Signed-off-by: Jakub Kicinski

net: lapb: Add locking to the lapb module

2021-01-27T01:53:45+00:00

In the lapb module, the timers may run concurrently with other code in this module, and there is currently no locking to prevent the code from racing on "struct lapb_cb". This patch adds locking to prevent racing. 1. Add "spinlock_t lock" to "struct lapb_cb"; Add "spin_lock_bh" and "spin_unlock_bh" to APIs, timer functions and notifier functions. 2. Add "bool t1timer_stop, t2timer_stop" to "struct lapb_cb" to make us able to ask running timers to abort; Modify "lapb_stop_t1timer" and "lapb_stop_t2timer" to make them able to abort running timers; Modify "lapb_t2timer_expiry" and "lapb_t1timer_expiry" to make them abort after they are stopped by "lapb_stop_t1timer", "lapb_stop_t2timer", and "lapb_start_t1timer", "lapb_start_t2timer". 3. Let lapb_unregister wait for other API functions and running timers to stop. 4. The lapb_device_event function calls lapb_disconnect_request. In order to avoid trying to hold the lock twice, add a new function named "__lapb_disconnect_request" which assumes the lock is held, and make it called by lapb_disconnect_request and lapb_device_event. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Cc: Martin Schiller Signed-off-by: Xie He Link: https://lore.kernel.org/r/20210126040939.69995-1-xie.he.0141@gmail.com Signed-off-by: Jakub Kicinski

net: lapb: Decrease the refcount of "struct lapb_cb" in lapb_device_event

2021-01-04T21:42:41+00:00

In lapb_device_event, lapb_devtostruct is called to get a reference to an object of "struct lapb_cb". lapb_devtostruct increases the refcount of the object and returns a pointer to it. However, we didn't decrease the refcount after we finished using the pointer. This patch fixes this problem. Fixes: a4989fa91110 ("net/lapb: support netdev events") Cc: Martin Schiller Signed-off-by: Xie He Link: https://lore.kernel.org/r/20201231174331.64539-1-xie.he.0141@gmail.com Signed-off-by: Jakub Kicinski

net/lapb: fix t1 timer handling for LAPB_STATE_0

2020-11-28T01:22:51+00:00

1. DTE interface changes immediately to LAPB_STATE_1 and start sending SABM(E). 2. DCE interface sends N2-times DM and changes to LAPB_STATE_1 afterwards if there is no response in the meantime. Signed-off-by: Martin Schiller Signed-off-by: Jakub Kicinski

net/lapb: support netdev events

2020-11-28T01:22:51+00:00

This patch allows layer2 (LAPB) to react to netdev events itself and avoids the detour via layer3 (X.25). 1. Establish layer2 on NETDEV_UP events, if the carrier is already up. 2. Call lapb_disconnect_request() on NETDEV_GOING_DOWN events to signal the peer that the connection will go down. (Only when the carrier is up.) 3. When a NETDEV_DOWN event occur, clear all queues, enter state LAPB_STATE_0 and stop all timers. 4. The NETDEV_CHANGE event makes it possible to handle carrier loss and detection. In case of Carrier Loss, clear all queues, enter state LAPB_STATE_0 and stop all timers. In case of Carrier Detection, we start timer t1 on a DCE interface, and on a DTE interface we change to state LAPB_STATE_1 and start sending SABM(E). Signed-off-by: Martin Schiller Acked-by: Xie He Signed-off-by: Jakub Kicinski

treewide: replace '---help---' in Kconfig files with 'help'

2020-06-13T16:57:21+00:00

Since commit 84af7a6194e4 ("checkpatch: kconfig: prefer 'help' over '---help---'"), the number of '---help---' has been gradually decreasing, but there are still more than 2400 instances. This commit finishes the conversion. While I touched the lines, I also fixed the indentation. There are a variety of indentation styles found. a) 4 spaces + '---help---' b) 7 spaces + '---help---' c) 8 spaces + '---help---' d) 1 space + 1 tab + '---help---' e) 1 tab + '---help---' (correct indentation) f) 1 tab + 1 space + '---help---' g) 1 tab + 2 spaces + '---help---' In order to convert all of them to 1 tab + 'help', I ran the following commend: $ find . -name 'Kconfig*' | xargs sed -i 's/^[[:space:]]*---help---/\thelp/' Signed-off-by: Masahiro Yamada

docs: networking: convert lapb-module.txt to ReST

2020-04-30T19:56:35+00:00

- add SPDX header; - adjust title markup; - mark code blocks and literals as such; - mark tables as such; - adjust identation, whitespaces and blank lines; - add to networking/index.rst. Signed-off-by: Mauro Carvalho Chehab Signed-off-by: David S. Miller

Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net

2019-06-18T03:20:36+00:00

Honestly all the conflicts were simple overlapping changes, nothing really interesting to report. Signed-off-by: David S. Miller