Something went wrong. Try again.
(I'm so sorry!) Linux kernel mirror (for testing) git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel os linux
Something went wrong. Try again.
123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121/* SPDX-License-Identifier: GPL-2.0-or-later */
#ifndef _NET_GSO_H#define _NET_GSO_H
#include <linux/skbuff.h>
/* Keeps track of mac header offset relative to skb->head. * It is useful for TSO of Tunneling protocol. e.g. GRE. * For non-tunnel skb it points to skb_mac_header() and for * tunnel skb it points to outer mac header. * Keeps track of level of encapsulation of network headers. */struct skb_gso_cb { union { int mac_offset; int data_offset; }; int encap_level; __wsum csum; __u16 csum_start; /* Number of IPv4/IPv6 GSO handler entries for this packet. */ u8 recursion_counter; /* Max MSS segs per output skb, 0 = no limit */ u8 max_segs;};#define SKB_GSO_CB_OFFSET 32#define SKB_GSO_CB(skb) ((struct skb_gso_cb *)((skb)->cb + SKB_GSO_CB_OFFSET))
static inline bool gso_recursion_inc_test(struct sk_buff *skb, unsigned int limit){ return ++SKB_GSO_CB(skb)->recursion_counter > limit;}
static inline int skb_tnl_header_len(const struct sk_buff *inner_skb){ return (skb_mac_header(inner_skb) - inner_skb->head) - SKB_GSO_CB(inner_skb)->mac_offset;}
static inline int gso_pskb_expand_head(struct sk_buff *skb, int extra){ int new_headroom, headroom; int ret;
headroom = skb_headroom(skb); ret = pskb_expand_head(skb, extra, 0, GFP_ATOMIC); if (ret) return ret;
new_headroom = skb_headroom(skb); SKB_GSO_CB(skb)->mac_offset += (new_headroom - headroom); return 0;}
static inline void gso_reset_checksum(struct sk_buff *skb, __wsum res){ /* Do not update partial checksums if remote checksum is enabled. */ if (skb->remcsum_offload) return;
SKB_GSO_CB(skb)->csum = res; SKB_GSO_CB(skb)->csum_start = skb_checksum_start(skb) - skb->head;}
/* Compute the checksum for a gso segment. First compute the checksum value * from the start of transport header to SKB_GSO_CB(skb)->csum_start, and * then add in skb->csum (checksum from csum_start to end of packet). * skb->csum and csum_start are then updated to reflect the checksum of the * resultant packet starting from the transport header-- the resultant checksum * is in the res argument (i.e. normally zero or ~ of checksum of a pseudo * header. */static inline __sum16 gso_make_checksum(struct sk_buff *skb, __wsum res){ unsigned char *csum_start = skb_transport_header(skb); int plen = (skb->head + SKB_GSO_CB(skb)->csum_start) - csum_start; __wsum partial = SKB_GSO_CB(skb)->csum;
SKB_GSO_CB(skb)->csum = res; SKB_GSO_CB(skb)->csum_start = csum_start - skb->head;
return csum_fold(csum_partial(csum_start, plen, partial));}
struct sk_buff *__skb_gso_segment(struct sk_buff *skb, netdev_features_t features, bool tx_path, unsigned int max_segs);
static inline struct sk_buff *skb_gso_segment(struct sk_buff *skb, netdev_features_t features){ return __skb_gso_segment(skb, features, true, 0);}
struct sk_buff *skb_eth_gso_segment(struct sk_buff *skb, netdev_features_t features, __be16 type);
struct sk_buff *skb_mac_gso_segment(struct sk_buff *skb, netdev_features_t features);
bool skb_gso_validate_network_len(const struct sk_buff *skb, unsigned int mtu);
bool skb_gso_validate_mac_len(const struct sk_buff *skb, unsigned int len);
static inline void skb_gso_error_unwind(struct sk_buff *skb, __be16 protocol, int pulled_hlen, u16 mac_offset, int mac_len){ skb->protocol = protocol; skb->encapsulation = 1; skb_push(skb, pulled_hlen); skb_reset_transport_header(skb); skb->mac_header = mac_offset; skb->network_header = skb->mac_header + mac_len; skb->mac_len = mac_len;}
#endif /* _NET_GSO_H */