mirror of
https://github.com/edk2-porting/linux-next.git
synced 2024-12-27 06:34:11 +08:00
30 lines
1.0 KiB
ReStructuredText
30 lines
1.0 KiB
ReStructuredText
|
.. SPDX-License-Identifier: GPL-2.0
|
||
|
|
|
||
|
|
================================
|
||
|
|
TC Actions - Environmental Rules
|
||
|
|
================================
|
||
|
|
|
||
|
|
|
||
|
|
The "environmental" rules for authors of any new tc actions are:
|
||
|
|
|
||
|
|
1) If you stealeth or borroweth any packet thou shalt be branching
|
||
|
|
from the righteous path and thou shalt cloneth.
|
||
|
|
|
||
|
|
For example if your action queues a packet to be processed later,
|
||
|
|
or intentionally branches by redirecting a packet, then you need to
|
||
|
|
clone the packet.
|
||
|
|
|
||
|
|
2) If you munge any packet thou shalt call pskb_expand_head in the case
|
||
|
|
someone else is referencing the skb. After that you "own" the skb.
|
||
|
|
|
||
|
|
3) Dropping packets you don't own is a no-no. You simply return
|
||
|
|
TC_ACT_SHOT to the caller and they will drop it.
|
||
|
|
|
||
|
|
The "environmental" rules for callers of actions (qdiscs etc) are:
|
||
|
|
|
||
|
|
#) Thou art responsible for freeing anything returned as being
|
||
|
|
TC_ACT_SHOT/STOLEN/QUEUED. If none of TC_ACT_SHOT/STOLEN/QUEUED is
|
||
|
|
returned, then all is great and you don't need to do anything.
|
||
|
|
|
||
|
|
Post on netdev if something is unclear.
|