| 1 | .. SPDX-License-Identifier: GPL-2.0 |
| 2 | |
| 3 | struct sk_buff |
| 4 | ============== |
| 5 | |
| 6 | :c:type:`sk_buff` is the main networking structure representing |
| 7 | a packet. |
| 8 | |
| 9 | Basic sk_buff geometry |
| 10 | ---------------------- |
| 11 | |
| 12 | .. kernel-doc:: include/linux/skbuff.h |
| 13 | :doc: Basic sk_buff geometry |
| 14 | |
| 15 | Shared skbs and skb clones |
| 16 | -------------------------- |
| 17 | |
| 18 | :c:member:`sk_buff.users` is a simple refcount allowing multiple entities |
| 19 | to keep a struct sk_buff alive. skbs with a ``sk_buff.users != 1`` are referred |
| 20 | to as shared skbs (see skb_shared()). |
| 21 | |
| 22 | skb_clone() allows for fast duplication of skbs. None of the data buffers |
| 23 | get copied, but caller gets a new metadata struct (struct sk_buff). |
| 24 | &skb_shared_info.refcount indicates the number of skbs pointing at the same |
| 25 | packet data (i.e. clones). |
| 26 | |
| 27 | dataref and headerless skbs |
| 28 | --------------------------- |
| 29 | |
| 30 | .. kernel-doc:: include/linux/skbuff.h |
| 31 | :doc: dataref and headerless skbs |
| 32 | |
| 33 | Checksum information |
| 34 | -------------------- |
| 35 | |
| 36 | .. kernel-doc:: include/linux/skbuff.h |
| 37 | :doc: skb checksums |