d2461edde7
- add SPDX header; - add a document title; - use the right numbered list markup; - adjust identation, whitespaces and blank lines where needed; - add to networking/index.rst. Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
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1.0 KiB
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30 lines
1.0 KiB
ReStructuredText
.. SPDX-License-Identifier: GPL-2.0
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================================
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TC Actions - Environmental Rules
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================================
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The "environmental" rules for authors of any new tc actions are:
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1) If you stealeth or borroweth any packet thou shalt be branching
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from the righteous path and thou shalt cloneth.
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For example if your action queues a packet to be processed later,
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or intentionally branches by redirecting a packet, then you need to
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clone the packet.
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2) If you munge any packet thou shalt call pskb_expand_head in the case
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someone else is referencing the skb. After that you "own" the skb.
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3) Dropping packets you don't own is a no-no. You simply return
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TC_ACT_SHOT to the caller and they will drop it.
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The "environmental" rules for callers of actions (qdiscs etc) are:
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#) Thou art responsible for freeing anything returned as being
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TC_ACT_SHOT/STOLEN/QUEUED. If none of TC_ACT_SHOT/STOLEN/QUEUED is
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returned, then all is great and you don't need to do anything.
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Post on netdev if something is unclear.
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