9facd94114
Long time ago Tom added a giant comment to skbuff.h explaining checksums. Now that we have a place in Documentation for skbuff docs we should render it. Sprinkle some markup while at it. Reviewed-by: David Ahern <dsahern@kernel.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
38 lines
995 B
ReStructuredText
38 lines
995 B
ReStructuredText
.. SPDX-License-Identifier: GPL-2.0
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struct sk_buff
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==============
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:c:type:`sk_buff` is the main networking structure representing
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a packet.
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Basic sk_buff geometry
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----------------------
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.. kernel-doc:: include/linux/skbuff.h
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:doc: Basic sk_buff geometry
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Shared skbs and skb clones
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--------------------------
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:c:member:`sk_buff.users` is a simple refcount allowing multiple entities
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to keep a struct sk_buff alive. skbs with a ``sk_buff.users != 1`` are referred
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to as shared skbs (see skb_shared()).
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skb_clone() allows for fast duplication of skbs. None of the data buffers
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get copied, but caller gets a new metadata struct (struct sk_buff).
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&skb_shared_info.refcount indicates the number of skbs pointing at the same
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packet data (i.e. clones).
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dataref and headerless skbs
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---------------------------
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.. kernel-doc:: include/linux/skbuff.h
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:doc: dataref and headerless skbs
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Checksum information
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--------------------
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.. kernel-doc:: include/linux/skbuff.h
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:doc: skb checksums
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