cbb042f9e1
We're now starting to have quite a number of places that do skb_pull followed immediately by an skb_postpull_rcsum. We can merge these two operations into one function with skb_pull_rcsum. This makes sense since most pull operations on receive skb's need to update the checksum. I've decided to make this out-of-line since it is fairly big and the fast path where hardware checksums are enabled need to call csum_partial anyway. Since this is a brand new function we get to add an extra check on the len argument. As it is most callers of skb_pull ignore its return value which essentially means that there is no check on the len argument. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
1373 lines
38 KiB
C
1373 lines
38 KiB
C
/*
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* Definitions for the 'struct sk_buff' memory handlers.
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*
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* Authors:
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* Alan Cox, <gw4pts@gw4pts.ampr.org>
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* Florian La Roche, <rzsfl@rz.uni-sb.de>
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation; either version
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* 2 of the License, or (at your option) any later version.
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*/
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#ifndef _LINUX_SKBUFF_H
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#define _LINUX_SKBUFF_H
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#include <linux/config.h>
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#include <linux/kernel.h>
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#include <linux/compiler.h>
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#include <linux/time.h>
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#include <linux/cache.h>
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#include <asm/atomic.h>
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#include <asm/types.h>
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#include <linux/spinlock.h>
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#include <linux/mm.h>
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#include <linux/highmem.h>
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#include <linux/poll.h>
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#include <linux/net.h>
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#include <linux/textsearch.h>
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#include <net/checksum.h>
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#define HAVE_ALLOC_SKB /* For the drivers to know */
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#define HAVE_ALIGNABLE_SKB /* Ditto 8) */
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#define CHECKSUM_NONE 0
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#define CHECKSUM_HW 1
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#define CHECKSUM_UNNECESSARY 2
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#define SKB_DATA_ALIGN(X) (((X) + (SMP_CACHE_BYTES - 1)) & \
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~(SMP_CACHE_BYTES - 1))
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#define SKB_MAX_ORDER(X, ORDER) (((PAGE_SIZE << (ORDER)) - (X) - \
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sizeof(struct skb_shared_info)) & \
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~(SMP_CACHE_BYTES - 1))
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#define SKB_MAX_HEAD(X) (SKB_MAX_ORDER((X), 0))
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#define SKB_MAX_ALLOC (SKB_MAX_ORDER(0, 2))
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/* A. Checksumming of received packets by device.
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*
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* NONE: device failed to checksum this packet.
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* skb->csum is undefined.
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*
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* UNNECESSARY: device parsed packet and wouldbe verified checksum.
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* skb->csum is undefined.
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* It is bad option, but, unfortunately, many of vendors do this.
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* Apparently with secret goal to sell you new device, when you
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* will add new protocol to your host. F.e. IPv6. 8)
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*
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* HW: the most generic way. Device supplied checksum of _all_
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* the packet as seen by netif_rx in skb->csum.
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* NOTE: Even if device supports only some protocols, but
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* is able to produce some skb->csum, it MUST use HW,
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* not UNNECESSARY.
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*
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* B. Checksumming on output.
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*
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* NONE: skb is checksummed by protocol or csum is not required.
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*
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* HW: device is required to csum packet as seen by hard_start_xmit
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* from skb->h.raw to the end and to record the checksum
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* at skb->h.raw+skb->csum.
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*
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* Device must show its capabilities in dev->features, set
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* at device setup time.
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* NETIF_F_HW_CSUM - it is clever device, it is able to checksum
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* everything.
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* NETIF_F_NO_CSUM - loopback or reliable single hop media.
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* NETIF_F_IP_CSUM - device is dumb. It is able to csum only
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* TCP/UDP over IPv4. Sigh. Vendors like this
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* way by an unknown reason. Though, see comment above
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* about CHECKSUM_UNNECESSARY. 8)
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*
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* Any questions? No questions, good. --ANK
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*/
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struct net_device;
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#ifdef CONFIG_NETFILTER
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struct nf_conntrack {
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atomic_t use;
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void (*destroy)(struct nf_conntrack *);
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};
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#ifdef CONFIG_BRIDGE_NETFILTER
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struct nf_bridge_info {
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atomic_t use;
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struct net_device *physindev;
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struct net_device *physoutdev;
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#if defined(CONFIG_VLAN_8021Q) || defined(CONFIG_VLAN_8021Q_MODULE)
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struct net_device *netoutdev;
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#endif
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unsigned int mask;
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unsigned long data[32 / sizeof(unsigned long)];
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};
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#endif
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#endif
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struct sk_buff_head {
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/* These two members must be first. */
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struct sk_buff *next;
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struct sk_buff *prev;
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__u32 qlen;
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spinlock_t lock;
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};
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struct sk_buff;
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/* To allow 64K frame to be packed as single skb without frag_list */
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#define MAX_SKB_FRAGS (65536/PAGE_SIZE + 2)
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typedef struct skb_frag_struct skb_frag_t;
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struct skb_frag_struct {
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struct page *page;
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__u16 page_offset;
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__u16 size;
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};
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/* This data is invariant across clones and lives at
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* the end of the header data, ie. at skb->end.
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*/
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struct skb_shared_info {
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atomic_t dataref;
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unsigned short nr_frags;
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unsigned short tso_size;
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unsigned short tso_segs;
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unsigned short ufo_size;
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unsigned int ip6_frag_id;
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struct sk_buff *frag_list;
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skb_frag_t frags[MAX_SKB_FRAGS];
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};
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/* We divide dataref into two halves. The higher 16 bits hold references
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* to the payload part of skb->data. The lower 16 bits hold references to
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* the entire skb->data. It is up to the users of the skb to agree on
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* where the payload starts.
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*
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* All users must obey the rule that the skb->data reference count must be
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* greater than or equal to the payload reference count.
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*
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* Holding a reference to the payload part means that the user does not
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* care about modifications to the header part of skb->data.
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*/
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#define SKB_DATAREF_SHIFT 16
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#define SKB_DATAREF_MASK ((1 << SKB_DATAREF_SHIFT) - 1)
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struct skb_timeval {
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u32 off_sec;
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u32 off_usec;
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};
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enum {
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SKB_FCLONE_UNAVAILABLE,
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SKB_FCLONE_ORIG,
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SKB_FCLONE_CLONE,
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};
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/**
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* struct sk_buff - socket buffer
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* @next: Next buffer in list
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* @prev: Previous buffer in list
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* @sk: Socket we are owned by
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* @tstamp: Time we arrived
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* @dev: Device we arrived on/are leaving by
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* @input_dev: Device we arrived on
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* @h: Transport layer header
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* @nh: Network layer header
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* @mac: Link layer header
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* @dst: destination entry
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* @sp: the security path, used for xfrm
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* @cb: Control buffer. Free for use by every layer. Put private vars here
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* @len: Length of actual data
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* @data_len: Data length
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* @mac_len: Length of link layer header
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* @csum: Checksum
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* @local_df: allow local fragmentation
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* @cloned: Head may be cloned (check refcnt to be sure)
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* @nohdr: Payload reference only, must not modify header
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* @pkt_type: Packet class
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* @fclone: skbuff clone status
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* @ip_summed: Driver fed us an IP checksum
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* @priority: Packet queueing priority
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* @users: User count - see {datagram,tcp}.c
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* @protocol: Packet protocol from driver
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* @truesize: Buffer size
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* @head: Head of buffer
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* @data: Data head pointer
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* @tail: Tail pointer
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* @end: End pointer
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* @destructor: Destruct function
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* @nfmark: Can be used for communication between hooks
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* @nfct: Associated connection, if any
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* @ipvs_property: skbuff is owned by ipvs
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* @nfctinfo: Relationship of this skb to the connection
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* @nfct_reasm: netfilter conntrack re-assembly pointer
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* @nf_bridge: Saved data about a bridged frame - see br_netfilter.c
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* @tc_index: Traffic control index
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* @tc_verd: traffic control verdict
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*/
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struct sk_buff {
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/* These two members must be first. */
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struct sk_buff *next;
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struct sk_buff *prev;
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struct sock *sk;
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struct skb_timeval tstamp;
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struct net_device *dev;
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struct net_device *input_dev;
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union {
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struct tcphdr *th;
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struct udphdr *uh;
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struct icmphdr *icmph;
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struct igmphdr *igmph;
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struct iphdr *ipiph;
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struct ipv6hdr *ipv6h;
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unsigned char *raw;
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} h;
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union {
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struct iphdr *iph;
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struct ipv6hdr *ipv6h;
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struct arphdr *arph;
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unsigned char *raw;
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} nh;
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union {
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unsigned char *raw;
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} mac;
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struct dst_entry *dst;
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struct sec_path *sp;
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/*
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* This is the control buffer. It is free to use for every
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* layer. Please put your private variables there. If you
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* want to keep them across layers you have to do a skb_clone()
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* first. This is owned by whoever has the skb queued ATM.
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*/
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char cb[48];
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unsigned int len,
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data_len,
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mac_len,
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csum;
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__u32 priority;
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__u8 local_df:1,
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cloned:1,
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ip_summed:2,
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nohdr:1,
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nfctinfo:3;
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__u8 pkt_type:3,
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fclone:2,
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ipvs_property:1;
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__be16 protocol;
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void (*destructor)(struct sk_buff *skb);
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#ifdef CONFIG_NETFILTER
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struct nf_conntrack *nfct;
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#if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
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struct sk_buff *nfct_reasm;
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#endif
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#ifdef CONFIG_BRIDGE_NETFILTER
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struct nf_bridge_info *nf_bridge;
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#endif
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__u32 nfmark;
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#endif /* CONFIG_NETFILTER */
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#ifdef CONFIG_NET_SCHED
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__u16 tc_index; /* traffic control index */
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#ifdef CONFIG_NET_CLS_ACT
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__u16 tc_verd; /* traffic control verdict */
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#endif
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#endif
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/* These elements must be at the end, see alloc_skb() for details. */
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unsigned int truesize;
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atomic_t users;
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unsigned char *head,
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*data,
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*tail,
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*end;
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};
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#ifdef __KERNEL__
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/*
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* Handling routines are only of interest to the kernel
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*/
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#include <linux/slab.h>
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#include <asm/system.h>
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extern void kfree_skb(struct sk_buff *skb);
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extern void __kfree_skb(struct sk_buff *skb);
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extern struct sk_buff *__alloc_skb(unsigned int size,
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gfp_t priority, int fclone);
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static inline struct sk_buff *alloc_skb(unsigned int size,
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gfp_t priority)
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{
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return __alloc_skb(size, priority, 0);
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}
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static inline struct sk_buff *alloc_skb_fclone(unsigned int size,
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gfp_t priority)
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{
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return __alloc_skb(size, priority, 1);
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}
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extern struct sk_buff *alloc_skb_from_cache(kmem_cache_t *cp,
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unsigned int size,
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gfp_t priority);
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extern void kfree_skbmem(struct sk_buff *skb);
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extern struct sk_buff *skb_clone(struct sk_buff *skb,
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gfp_t priority);
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extern struct sk_buff *skb_copy(const struct sk_buff *skb,
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gfp_t priority);
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extern struct sk_buff *pskb_copy(struct sk_buff *skb,
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gfp_t gfp_mask);
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extern int pskb_expand_head(struct sk_buff *skb,
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int nhead, int ntail,
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gfp_t gfp_mask);
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extern struct sk_buff *skb_realloc_headroom(struct sk_buff *skb,
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unsigned int headroom);
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extern struct sk_buff *skb_copy_expand(const struct sk_buff *skb,
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int newheadroom, int newtailroom,
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gfp_t priority);
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extern struct sk_buff * skb_pad(struct sk_buff *skb, int pad);
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#define dev_kfree_skb(a) kfree_skb(a)
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extern void skb_over_panic(struct sk_buff *skb, int len,
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void *here);
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extern void skb_under_panic(struct sk_buff *skb, int len,
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void *here);
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extern int skb_append_datato_frags(struct sock *sk, struct sk_buff *skb,
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int getfrag(void *from, char *to, int offset,
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int len,int odd, struct sk_buff *skb),
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void *from, int length);
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struct skb_seq_state
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{
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__u32 lower_offset;
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__u32 upper_offset;
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__u32 frag_idx;
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__u32 stepped_offset;
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struct sk_buff *root_skb;
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struct sk_buff *cur_skb;
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__u8 *frag_data;
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};
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extern void skb_prepare_seq_read(struct sk_buff *skb,
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unsigned int from, unsigned int to,
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struct skb_seq_state *st);
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extern unsigned int skb_seq_read(unsigned int consumed, const u8 **data,
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struct skb_seq_state *st);
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extern void skb_abort_seq_read(struct skb_seq_state *st);
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extern unsigned int skb_find_text(struct sk_buff *skb, unsigned int from,
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unsigned int to, struct ts_config *config,
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struct ts_state *state);
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/* Internal */
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#define skb_shinfo(SKB) ((struct skb_shared_info *)((SKB)->end))
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/**
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* skb_queue_empty - check if a queue is empty
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* @list: queue head
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*
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* Returns true if the queue is empty, false otherwise.
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*/
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static inline int skb_queue_empty(const struct sk_buff_head *list)
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{
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return list->next == (struct sk_buff *)list;
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}
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/**
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* skb_get - reference buffer
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* @skb: buffer to reference
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*
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* Makes another reference to a socket buffer and returns a pointer
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* to the buffer.
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*/
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static inline struct sk_buff *skb_get(struct sk_buff *skb)
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{
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atomic_inc(&skb->users);
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return skb;
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}
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/*
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* If users == 1, we are the only owner and are can avoid redundant
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* atomic change.
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*/
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/**
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* skb_cloned - is the buffer a clone
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* @skb: buffer to check
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*
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* Returns true if the buffer was generated with skb_clone() and is
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* one of multiple shared copies of the buffer. Cloned buffers are
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* shared data so must not be written to under normal circumstances.
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*/
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static inline int skb_cloned(const struct sk_buff *skb)
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{
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return skb->cloned &&
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(atomic_read(&skb_shinfo(skb)->dataref) & SKB_DATAREF_MASK) != 1;
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}
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/**
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* skb_header_cloned - is the header a clone
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* @skb: buffer to check
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*
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* Returns true if modifying the header part of the buffer requires
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* the data to be copied.
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*/
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static inline int skb_header_cloned(const struct sk_buff *skb)
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{
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int dataref;
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if (!skb->cloned)
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return 0;
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dataref = atomic_read(&skb_shinfo(skb)->dataref);
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dataref = (dataref & SKB_DATAREF_MASK) - (dataref >> SKB_DATAREF_SHIFT);
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return dataref != 1;
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}
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/**
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* skb_header_release - release reference to header
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* @skb: buffer to operate on
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*
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* Drop a reference to the header part of the buffer. This is done
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* by acquiring a payload reference. You must not read from the header
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* part of skb->data after this.
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*/
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static inline void skb_header_release(struct sk_buff *skb)
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{
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BUG_ON(skb->nohdr);
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skb->nohdr = 1;
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atomic_add(1 << SKB_DATAREF_SHIFT, &skb_shinfo(skb)->dataref);
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}
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/**
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* skb_shared - is the buffer shared
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* @skb: buffer to check
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*
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* Returns true if more than one person has a reference to this
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* buffer.
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*/
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static inline int skb_shared(const struct sk_buff *skb)
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{
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return atomic_read(&skb->users) != 1;
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}
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/**
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* skb_share_check - check if buffer is shared and if so clone it
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* @skb: buffer to check
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* @pri: priority for memory allocation
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*
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* If the buffer is shared the buffer is cloned and the old copy
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* drops a reference. A new clone with a single reference is returned.
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* If the buffer is not shared the original buffer is returned. When
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* being called from interrupt status or with spinlocks held pri must
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* be GFP_ATOMIC.
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*
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* NULL is returned on a memory allocation failure.
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*/
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static inline struct sk_buff *skb_share_check(struct sk_buff *skb,
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gfp_t pri)
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{
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might_sleep_if(pri & __GFP_WAIT);
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if (skb_shared(skb)) {
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struct sk_buff *nskb = skb_clone(skb, pri);
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kfree_skb(skb);
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skb = nskb;
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}
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return skb;
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}
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|
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/*
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|
* Copy shared buffers into a new sk_buff. We effectively do COW on
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* packets to handle cases where we have a local reader and forward
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* and a couple of other messy ones. The normal one is tcpdumping
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* a packet thats being forwarded.
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*/
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|
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/**
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* skb_unshare - make a copy of a shared buffer
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* @skb: buffer to check
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* @pri: priority for memory allocation
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*
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* If the socket buffer is a clone then this function creates a new
|
|
* copy of the data, drops a reference count on the old copy and returns
|
|
* the new copy with the reference count at 1. If the buffer is not a clone
|
|
* the original buffer is returned. When called with a spinlock held or
|
|
* from interrupt state @pri must be %GFP_ATOMIC
|
|
*
|
|
* %NULL is returned on a memory allocation failure.
|
|
*/
|
|
static inline struct sk_buff *skb_unshare(struct sk_buff *skb,
|
|
gfp_t pri)
|
|
{
|
|
might_sleep_if(pri & __GFP_WAIT);
|
|
if (skb_cloned(skb)) {
|
|
struct sk_buff *nskb = skb_copy(skb, pri);
|
|
kfree_skb(skb); /* Free our shared copy */
|
|
skb = nskb;
|
|
}
|
|
return skb;
|
|
}
|
|
|
|
/**
|
|
* skb_peek
|
|
* @list_: list to peek at
|
|
*
|
|
* Peek an &sk_buff. Unlike most other operations you _MUST_
|
|
* be careful with this one. A peek leaves the buffer on the
|
|
* list and someone else may run off with it. You must hold
|
|
* the appropriate locks or have a private queue to do this.
|
|
*
|
|
* Returns %NULL for an empty list or a pointer to the head element.
|
|
* The reference count is not incremented and the reference is therefore
|
|
* volatile. Use with caution.
|
|
*/
|
|
static inline struct sk_buff *skb_peek(struct sk_buff_head *list_)
|
|
{
|
|
struct sk_buff *list = ((struct sk_buff *)list_)->next;
|
|
if (list == (struct sk_buff *)list_)
|
|
list = NULL;
|
|
return list;
|
|
}
|
|
|
|
/**
|
|
* skb_peek_tail
|
|
* @list_: list to peek at
|
|
*
|
|
* Peek an &sk_buff. Unlike most other operations you _MUST_
|
|
* be careful with this one. A peek leaves the buffer on the
|
|
* list and someone else may run off with it. You must hold
|
|
* the appropriate locks or have a private queue to do this.
|
|
*
|
|
* Returns %NULL for an empty list or a pointer to the tail element.
|
|
* The reference count is not incremented and the reference is therefore
|
|
* volatile. Use with caution.
|
|
*/
|
|
static inline struct sk_buff *skb_peek_tail(struct sk_buff_head *list_)
|
|
{
|
|
struct sk_buff *list = ((struct sk_buff *)list_)->prev;
|
|
if (list == (struct sk_buff *)list_)
|
|
list = NULL;
|
|
return list;
|
|
}
|
|
|
|
/**
|
|
* skb_queue_len - get queue length
|
|
* @list_: list to measure
|
|
*
|
|
* Return the length of an &sk_buff queue.
|
|
*/
|
|
static inline __u32 skb_queue_len(const struct sk_buff_head *list_)
|
|
{
|
|
return list_->qlen;
|
|
}
|
|
|
|
static inline void skb_queue_head_init(struct sk_buff_head *list)
|
|
{
|
|
spin_lock_init(&list->lock);
|
|
list->prev = list->next = (struct sk_buff *)list;
|
|
list->qlen = 0;
|
|
}
|
|
|
|
/*
|
|
* Insert an sk_buff at the start of a list.
|
|
*
|
|
* The "__skb_xxxx()" functions are the non-atomic ones that
|
|
* can only be called with interrupts disabled.
|
|
*/
|
|
|
|
/**
|
|
* __skb_queue_after - queue a buffer at the list head
|
|
* @list: list to use
|
|
* @prev: place after this buffer
|
|
* @newsk: buffer to queue
|
|
*
|
|
* Queue a buffer int the middle of a list. This function takes no locks
|
|
* and you must therefore hold required locks before calling it.
|
|
*
|
|
* A buffer cannot be placed on two lists at the same time.
|
|
*/
|
|
static inline void __skb_queue_after(struct sk_buff_head *list,
|
|
struct sk_buff *prev,
|
|
struct sk_buff *newsk)
|
|
{
|
|
struct sk_buff *next;
|
|
list->qlen++;
|
|
|
|
next = prev->next;
|
|
newsk->next = next;
|
|
newsk->prev = prev;
|
|
next->prev = prev->next = newsk;
|
|
}
|
|
|
|
/**
|
|
* __skb_queue_head - queue a buffer at the list head
|
|
* @list: list to use
|
|
* @newsk: buffer to queue
|
|
*
|
|
* Queue a buffer at the start of a list. This function takes no locks
|
|
* and you must therefore hold required locks before calling it.
|
|
*
|
|
* A buffer cannot be placed on two lists at the same time.
|
|
*/
|
|
extern void skb_queue_head(struct sk_buff_head *list, struct sk_buff *newsk);
|
|
static inline void __skb_queue_head(struct sk_buff_head *list,
|
|
struct sk_buff *newsk)
|
|
{
|
|
__skb_queue_after(list, (struct sk_buff *)list, newsk);
|
|
}
|
|
|
|
/**
|
|
* __skb_queue_tail - queue a buffer at the list tail
|
|
* @list: list to use
|
|
* @newsk: buffer to queue
|
|
*
|
|
* Queue a buffer at the end of a list. This function takes no locks
|
|
* and you must therefore hold required locks before calling it.
|
|
*
|
|
* A buffer cannot be placed on two lists at the same time.
|
|
*/
|
|
extern void skb_queue_tail(struct sk_buff_head *list, struct sk_buff *newsk);
|
|
static inline void __skb_queue_tail(struct sk_buff_head *list,
|
|
struct sk_buff *newsk)
|
|
{
|
|
struct sk_buff *prev, *next;
|
|
|
|
list->qlen++;
|
|
next = (struct sk_buff *)list;
|
|
prev = next->prev;
|
|
newsk->next = next;
|
|
newsk->prev = prev;
|
|
next->prev = prev->next = newsk;
|
|
}
|
|
|
|
|
|
/**
|
|
* __skb_dequeue - remove from the head of the queue
|
|
* @list: list to dequeue from
|
|
*
|
|
* Remove the head of the list. This function does not take any locks
|
|
* so must be used with appropriate locks held only. The head item is
|
|
* returned or %NULL if the list is empty.
|
|
*/
|
|
extern struct sk_buff *skb_dequeue(struct sk_buff_head *list);
|
|
static inline struct sk_buff *__skb_dequeue(struct sk_buff_head *list)
|
|
{
|
|
struct sk_buff *next, *prev, *result;
|
|
|
|
prev = (struct sk_buff *) list;
|
|
next = prev->next;
|
|
result = NULL;
|
|
if (next != prev) {
|
|
result = next;
|
|
next = next->next;
|
|
list->qlen--;
|
|
next->prev = prev;
|
|
prev->next = next;
|
|
result->next = result->prev = NULL;
|
|
}
|
|
return result;
|
|
}
|
|
|
|
|
|
/*
|
|
* Insert a packet on a list.
|
|
*/
|
|
extern void skb_insert(struct sk_buff *old, struct sk_buff *newsk, struct sk_buff_head *list);
|
|
static inline void __skb_insert(struct sk_buff *newsk,
|
|
struct sk_buff *prev, struct sk_buff *next,
|
|
struct sk_buff_head *list)
|
|
{
|
|
newsk->next = next;
|
|
newsk->prev = prev;
|
|
next->prev = prev->next = newsk;
|
|
list->qlen++;
|
|
}
|
|
|
|
/*
|
|
* Place a packet after a given packet in a list.
|
|
*/
|
|
extern void skb_append(struct sk_buff *old, struct sk_buff *newsk, struct sk_buff_head *list);
|
|
static inline void __skb_append(struct sk_buff *old, struct sk_buff *newsk, struct sk_buff_head *list)
|
|
{
|
|
__skb_insert(newsk, old, old->next, list);
|
|
}
|
|
|
|
/*
|
|
* remove sk_buff from list. _Must_ be called atomically, and with
|
|
* the list known..
|
|
*/
|
|
extern void skb_unlink(struct sk_buff *skb, struct sk_buff_head *list);
|
|
static inline void __skb_unlink(struct sk_buff *skb, struct sk_buff_head *list)
|
|
{
|
|
struct sk_buff *next, *prev;
|
|
|
|
list->qlen--;
|
|
next = skb->next;
|
|
prev = skb->prev;
|
|
skb->next = skb->prev = NULL;
|
|
next->prev = prev;
|
|
prev->next = next;
|
|
}
|
|
|
|
|
|
/* XXX: more streamlined implementation */
|
|
|
|
/**
|
|
* __skb_dequeue_tail - remove from the tail of the queue
|
|
* @list: list to dequeue from
|
|
*
|
|
* Remove the tail of the list. This function does not take any locks
|
|
* so must be used with appropriate locks held only. The tail item is
|
|
* returned or %NULL if the list is empty.
|
|
*/
|
|
extern struct sk_buff *skb_dequeue_tail(struct sk_buff_head *list);
|
|
static inline struct sk_buff *__skb_dequeue_tail(struct sk_buff_head *list)
|
|
{
|
|
struct sk_buff *skb = skb_peek_tail(list);
|
|
if (skb)
|
|
__skb_unlink(skb, list);
|
|
return skb;
|
|
}
|
|
|
|
|
|
static inline int skb_is_nonlinear(const struct sk_buff *skb)
|
|
{
|
|
return skb->data_len;
|
|
}
|
|
|
|
static inline unsigned int skb_headlen(const struct sk_buff *skb)
|
|
{
|
|
return skb->len - skb->data_len;
|
|
}
|
|
|
|
static inline int skb_pagelen(const struct sk_buff *skb)
|
|
{
|
|
int i, len = 0;
|
|
|
|
for (i = (int)skb_shinfo(skb)->nr_frags - 1; i >= 0; i--)
|
|
len += skb_shinfo(skb)->frags[i].size;
|
|
return len + skb_headlen(skb);
|
|
}
|
|
|
|
static inline void skb_fill_page_desc(struct sk_buff *skb, int i,
|
|
struct page *page, int off, int size)
|
|
{
|
|
skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
|
|
|
|
frag->page = page;
|
|
frag->page_offset = off;
|
|
frag->size = size;
|
|
skb_shinfo(skb)->nr_frags = i + 1;
|
|
}
|
|
|
|
#define SKB_PAGE_ASSERT(skb) BUG_ON(skb_shinfo(skb)->nr_frags)
|
|
#define SKB_FRAG_ASSERT(skb) BUG_ON(skb_shinfo(skb)->frag_list)
|
|
#define SKB_LINEAR_ASSERT(skb) BUG_ON(skb_is_nonlinear(skb))
|
|
|
|
/*
|
|
* Add data to an sk_buff
|
|
*/
|
|
static inline unsigned char *__skb_put(struct sk_buff *skb, unsigned int len)
|
|
{
|
|
unsigned char *tmp = skb->tail;
|
|
SKB_LINEAR_ASSERT(skb);
|
|
skb->tail += len;
|
|
skb->len += len;
|
|
return tmp;
|
|
}
|
|
|
|
/**
|
|
* skb_put - add data to a buffer
|
|
* @skb: buffer to use
|
|
* @len: amount of data to add
|
|
*
|
|
* This function extends the used data area of the buffer. If this would
|
|
* exceed the total buffer size the kernel will panic. A pointer to the
|
|
* first byte of the extra data is returned.
|
|
*/
|
|
static inline unsigned char *skb_put(struct sk_buff *skb, unsigned int len)
|
|
{
|
|
unsigned char *tmp = skb->tail;
|
|
SKB_LINEAR_ASSERT(skb);
|
|
skb->tail += len;
|
|
skb->len += len;
|
|
if (unlikely(skb->tail>skb->end))
|
|
skb_over_panic(skb, len, current_text_addr());
|
|
return tmp;
|
|
}
|
|
|
|
static inline unsigned char *__skb_push(struct sk_buff *skb, unsigned int len)
|
|
{
|
|
skb->data -= len;
|
|
skb->len += len;
|
|
return skb->data;
|
|
}
|
|
|
|
/**
|
|
* skb_push - add data to the start of a buffer
|
|
* @skb: buffer to use
|
|
* @len: amount of data to add
|
|
*
|
|
* This function extends the used data area of the buffer at the buffer
|
|
* start. If this would exceed the total buffer headroom the kernel will
|
|
* panic. A pointer to the first byte of the extra data is returned.
|
|
*/
|
|
static inline unsigned char *skb_push(struct sk_buff *skb, unsigned int len)
|
|
{
|
|
skb->data -= len;
|
|
skb->len += len;
|
|
if (unlikely(skb->data<skb->head))
|
|
skb_under_panic(skb, len, current_text_addr());
|
|
return skb->data;
|
|
}
|
|
|
|
static inline unsigned char *__skb_pull(struct sk_buff *skb, unsigned int len)
|
|
{
|
|
skb->len -= len;
|
|
BUG_ON(skb->len < skb->data_len);
|
|
return skb->data += len;
|
|
}
|
|
|
|
/**
|
|
* skb_pull - remove data from the start of a buffer
|
|
* @skb: buffer to use
|
|
* @len: amount of data to remove
|
|
*
|
|
* This function removes data from the start of a buffer, returning
|
|
* the memory to the headroom. A pointer to the next data in the buffer
|
|
* is returned. Once the data has been pulled future pushes will overwrite
|
|
* the old data.
|
|
*/
|
|
static inline unsigned char *skb_pull(struct sk_buff *skb, unsigned int len)
|
|
{
|
|
return unlikely(len > skb->len) ? NULL : __skb_pull(skb, len);
|
|
}
|
|
|
|
extern unsigned char *__pskb_pull_tail(struct sk_buff *skb, int delta);
|
|
|
|
static inline unsigned char *__pskb_pull(struct sk_buff *skb, unsigned int len)
|
|
{
|
|
if (len > skb_headlen(skb) &&
|
|
!__pskb_pull_tail(skb, len-skb_headlen(skb)))
|
|
return NULL;
|
|
skb->len -= len;
|
|
return skb->data += len;
|
|
}
|
|
|
|
static inline unsigned char *pskb_pull(struct sk_buff *skb, unsigned int len)
|
|
{
|
|
return unlikely(len > skb->len) ? NULL : __pskb_pull(skb, len);
|
|
}
|
|
|
|
static inline int pskb_may_pull(struct sk_buff *skb, unsigned int len)
|
|
{
|
|
if (likely(len <= skb_headlen(skb)))
|
|
return 1;
|
|
if (unlikely(len > skb->len))
|
|
return 0;
|
|
return __pskb_pull_tail(skb, len-skb_headlen(skb)) != NULL;
|
|
}
|
|
|
|
/**
|
|
* skb_headroom - bytes at buffer head
|
|
* @skb: buffer to check
|
|
*
|
|
* Return the number of bytes of free space at the head of an &sk_buff.
|
|
*/
|
|
static inline int skb_headroom(const struct sk_buff *skb)
|
|
{
|
|
return skb->data - skb->head;
|
|
}
|
|
|
|
/**
|
|
* skb_tailroom - bytes at buffer end
|
|
* @skb: buffer to check
|
|
*
|
|
* Return the number of bytes of free space at the tail of an sk_buff
|
|
*/
|
|
static inline int skb_tailroom(const struct sk_buff *skb)
|
|
{
|
|
return skb_is_nonlinear(skb) ? 0 : skb->end - skb->tail;
|
|
}
|
|
|
|
/**
|
|
* skb_reserve - adjust headroom
|
|
* @skb: buffer to alter
|
|
* @len: bytes to move
|
|
*
|
|
* Increase the headroom of an empty &sk_buff by reducing the tail
|
|
* room. This is only allowed for an empty buffer.
|
|
*/
|
|
static inline void skb_reserve(struct sk_buff *skb, int len)
|
|
{
|
|
skb->data += len;
|
|
skb->tail += len;
|
|
}
|
|
|
|
/*
|
|
* CPUs often take a performance hit when accessing unaligned memory
|
|
* locations. The actual performance hit varies, it can be small if the
|
|
* hardware handles it or large if we have to take an exception and fix it
|
|
* in software.
|
|
*
|
|
* Since an ethernet header is 14 bytes network drivers often end up with
|
|
* the IP header at an unaligned offset. The IP header can be aligned by
|
|
* shifting the start of the packet by 2 bytes. Drivers should do this
|
|
* with:
|
|
*
|
|
* skb_reserve(NET_IP_ALIGN);
|
|
*
|
|
* The downside to this alignment of the IP header is that the DMA is now
|
|
* unaligned. On some architectures the cost of an unaligned DMA is high
|
|
* and this cost outweighs the gains made by aligning the IP header.
|
|
*
|
|
* Since this trade off varies between architectures, we allow NET_IP_ALIGN
|
|
* to be overridden.
|
|
*/
|
|
#ifndef NET_IP_ALIGN
|
|
#define NET_IP_ALIGN 2
|
|
#endif
|
|
|
|
extern int ___pskb_trim(struct sk_buff *skb, unsigned int len, int realloc);
|
|
|
|
static inline void __skb_trim(struct sk_buff *skb, unsigned int len)
|
|
{
|
|
if (!skb->data_len) {
|
|
skb->len = len;
|
|
skb->tail = skb->data + len;
|
|
} else
|
|
___pskb_trim(skb, len, 0);
|
|
}
|
|
|
|
/**
|
|
* skb_trim - remove end from a buffer
|
|
* @skb: buffer to alter
|
|
* @len: new length
|
|
*
|
|
* Cut the length of a buffer down by removing data from the tail. If
|
|
* the buffer is already under the length specified it is not modified.
|
|
*/
|
|
static inline void skb_trim(struct sk_buff *skb, unsigned int len)
|
|
{
|
|
if (skb->len > len)
|
|
__skb_trim(skb, len);
|
|
}
|
|
|
|
|
|
static inline int __pskb_trim(struct sk_buff *skb, unsigned int len)
|
|
{
|
|
if (!skb->data_len) {
|
|
skb->len = len;
|
|
skb->tail = skb->data+len;
|
|
return 0;
|
|
}
|
|
return ___pskb_trim(skb, len, 1);
|
|
}
|
|
|
|
static inline int pskb_trim(struct sk_buff *skb, unsigned int len)
|
|
{
|
|
return (len < skb->len) ? __pskb_trim(skb, len) : 0;
|
|
}
|
|
|
|
/**
|
|
* skb_orphan - orphan a buffer
|
|
* @skb: buffer to orphan
|
|
*
|
|
* If a buffer currently has an owner then we call the owner's
|
|
* destructor function and make the @skb unowned. The buffer continues
|
|
* to exist but is no longer charged to its former owner.
|
|
*/
|
|
static inline void skb_orphan(struct sk_buff *skb)
|
|
{
|
|
if (skb->destructor)
|
|
skb->destructor(skb);
|
|
skb->destructor = NULL;
|
|
skb->sk = NULL;
|
|
}
|
|
|
|
/**
|
|
* __skb_queue_purge - empty a list
|
|
* @list: list to empty
|
|
*
|
|
* Delete all buffers on an &sk_buff list. Each buffer is removed from
|
|
* the list and one reference dropped. This function does not take the
|
|
* list lock and the caller must hold the relevant locks to use it.
|
|
*/
|
|
extern void skb_queue_purge(struct sk_buff_head *list);
|
|
static inline void __skb_queue_purge(struct sk_buff_head *list)
|
|
{
|
|
struct sk_buff *skb;
|
|
while ((skb = __skb_dequeue(list)) != NULL)
|
|
kfree_skb(skb);
|
|
}
|
|
|
|
#ifndef CONFIG_HAVE_ARCH_DEV_ALLOC_SKB
|
|
/**
|
|
* __dev_alloc_skb - allocate an skbuff for sending
|
|
* @length: length to allocate
|
|
* @gfp_mask: get_free_pages mask, passed to alloc_skb
|
|
*
|
|
* Allocate a new &sk_buff and assign it a usage count of one. The
|
|
* buffer has unspecified headroom built in. Users should allocate
|
|
* the headroom they think they need without accounting for the
|
|
* built in space. The built in space is used for optimisations.
|
|
*
|
|
* %NULL is returned in there is no free memory.
|
|
*/
|
|
static inline struct sk_buff *__dev_alloc_skb(unsigned int length,
|
|
gfp_t gfp_mask)
|
|
{
|
|
struct sk_buff *skb = alloc_skb(length + 16, gfp_mask);
|
|
if (likely(skb))
|
|
skb_reserve(skb, 16);
|
|
return skb;
|
|
}
|
|
#else
|
|
extern struct sk_buff *__dev_alloc_skb(unsigned int length, int gfp_mask);
|
|
#endif
|
|
|
|
/**
|
|
* dev_alloc_skb - allocate an skbuff for sending
|
|
* @length: length to allocate
|
|
*
|
|
* Allocate a new &sk_buff and assign it a usage count of one. The
|
|
* buffer has unspecified headroom built in. Users should allocate
|
|
* the headroom they think they need without accounting for the
|
|
* built in space. The built in space is used for optimisations.
|
|
*
|
|
* %NULL is returned in there is no free memory. Although this function
|
|
* allocates memory it can be called from an interrupt.
|
|
*/
|
|
static inline struct sk_buff *dev_alloc_skb(unsigned int length)
|
|
{
|
|
return __dev_alloc_skb(length, GFP_ATOMIC);
|
|
}
|
|
|
|
/**
|
|
* skb_cow - copy header of skb when it is required
|
|
* @skb: buffer to cow
|
|
* @headroom: needed headroom
|
|
*
|
|
* If the skb passed lacks sufficient headroom or its data part
|
|
* is shared, data is reallocated. If reallocation fails, an error
|
|
* is returned and original skb is not changed.
|
|
*
|
|
* The result is skb with writable area skb->head...skb->tail
|
|
* and at least @headroom of space at head.
|
|
*/
|
|
static inline int skb_cow(struct sk_buff *skb, unsigned int headroom)
|
|
{
|
|
int delta = (headroom > 16 ? headroom : 16) - skb_headroom(skb);
|
|
|
|
if (delta < 0)
|
|
delta = 0;
|
|
|
|
if (delta || skb_cloned(skb))
|
|
return pskb_expand_head(skb, (delta + 15) & ~15, 0, GFP_ATOMIC);
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* skb_padto - pad an skbuff up to a minimal size
|
|
* @skb: buffer to pad
|
|
* @len: minimal length
|
|
*
|
|
* Pads up a buffer to ensure the trailing bytes exist and are
|
|
* blanked. If the buffer already contains sufficient data it
|
|
* is untouched. Returns the buffer, which may be a replacement
|
|
* for the original, or NULL for out of memory - in which case
|
|
* the original buffer is still freed.
|
|
*/
|
|
|
|
static inline struct sk_buff *skb_padto(struct sk_buff *skb, unsigned int len)
|
|
{
|
|
unsigned int size = skb->len;
|
|
if (likely(size >= len))
|
|
return skb;
|
|
return skb_pad(skb, len-size);
|
|
}
|
|
|
|
static inline int skb_add_data(struct sk_buff *skb,
|
|
char __user *from, int copy)
|
|
{
|
|
const int off = skb->len;
|
|
|
|
if (skb->ip_summed == CHECKSUM_NONE) {
|
|
int err = 0;
|
|
unsigned int csum = csum_and_copy_from_user(from,
|
|
skb_put(skb, copy),
|
|
copy, 0, &err);
|
|
if (!err) {
|
|
skb->csum = csum_block_add(skb->csum, csum, off);
|
|
return 0;
|
|
}
|
|
} else if (!copy_from_user(skb_put(skb, copy), from, copy))
|
|
return 0;
|
|
|
|
__skb_trim(skb, off);
|
|
return -EFAULT;
|
|
}
|
|
|
|
static inline int skb_can_coalesce(struct sk_buff *skb, int i,
|
|
struct page *page, int off)
|
|
{
|
|
if (i) {
|
|
struct skb_frag_struct *frag = &skb_shinfo(skb)->frags[i - 1];
|
|
|
|
return page == frag->page &&
|
|
off == frag->page_offset + frag->size;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* skb_linearize - convert paged skb to linear one
|
|
* @skb: buffer to linarize
|
|
* @gfp: allocation mode
|
|
*
|
|
* If there is no free memory -ENOMEM is returned, otherwise zero
|
|
* is returned and the old skb data released.
|
|
*/
|
|
extern int __skb_linearize(struct sk_buff *skb, gfp_t gfp);
|
|
static inline int skb_linearize(struct sk_buff *skb, gfp_t gfp)
|
|
{
|
|
return __skb_linearize(skb, gfp);
|
|
}
|
|
|
|
/**
|
|
* skb_postpull_rcsum - update checksum for received skb after pull
|
|
* @skb: buffer to update
|
|
* @start: start of data before pull
|
|
* @len: length of data pulled
|
|
*
|
|
* After doing a pull on a received packet, you need to call this to
|
|
* update the CHECKSUM_HW checksum, or set ip_summed to CHECKSUM_NONE
|
|
* so that it can be recomputed from scratch.
|
|
*/
|
|
|
|
static inline void skb_postpull_rcsum(struct sk_buff *skb,
|
|
const void *start, unsigned int len)
|
|
{
|
|
if (skb->ip_summed == CHECKSUM_HW)
|
|
skb->csum = csum_sub(skb->csum, csum_partial(start, len, 0));
|
|
}
|
|
|
|
unsigned char *skb_pull_rcsum(struct sk_buff *skb, unsigned int len);
|
|
|
|
/**
|
|
* pskb_trim_rcsum - trim received skb and update checksum
|
|
* @skb: buffer to trim
|
|
* @len: new length
|
|
*
|
|
* This is exactly the same as pskb_trim except that it ensures the
|
|
* checksum of received packets are still valid after the operation.
|
|
*/
|
|
|
|
static inline int pskb_trim_rcsum(struct sk_buff *skb, unsigned int len)
|
|
{
|
|
if (likely(len >= skb->len))
|
|
return 0;
|
|
if (skb->ip_summed == CHECKSUM_HW)
|
|
skb->ip_summed = CHECKSUM_NONE;
|
|
return __pskb_trim(skb, len);
|
|
}
|
|
|
|
static inline void *kmap_skb_frag(const skb_frag_t *frag)
|
|
{
|
|
#ifdef CONFIG_HIGHMEM
|
|
BUG_ON(in_irq());
|
|
|
|
local_bh_disable();
|
|
#endif
|
|
return kmap_atomic(frag->page, KM_SKB_DATA_SOFTIRQ);
|
|
}
|
|
|
|
static inline void kunmap_skb_frag(void *vaddr)
|
|
{
|
|
kunmap_atomic(vaddr, KM_SKB_DATA_SOFTIRQ);
|
|
#ifdef CONFIG_HIGHMEM
|
|
local_bh_enable();
|
|
#endif
|
|
}
|
|
|
|
#define skb_queue_walk(queue, skb) \
|
|
for (skb = (queue)->next; \
|
|
prefetch(skb->next), (skb != (struct sk_buff *)(queue)); \
|
|
skb = skb->next)
|
|
|
|
#define skb_queue_reverse_walk(queue, skb) \
|
|
for (skb = (queue)->prev; \
|
|
prefetch(skb->prev), (skb != (struct sk_buff *)(queue)); \
|
|
skb = skb->prev)
|
|
|
|
|
|
extern struct sk_buff *skb_recv_datagram(struct sock *sk, unsigned flags,
|
|
int noblock, int *err);
|
|
extern unsigned int datagram_poll(struct file *file, struct socket *sock,
|
|
struct poll_table_struct *wait);
|
|
extern int skb_copy_datagram_iovec(const struct sk_buff *from,
|
|
int offset, struct iovec *to,
|
|
int size);
|
|
extern int skb_copy_and_csum_datagram_iovec(struct sk_buff *skb,
|
|
int hlen,
|
|
struct iovec *iov);
|
|
extern void skb_free_datagram(struct sock *sk, struct sk_buff *skb);
|
|
extern void skb_kill_datagram(struct sock *sk, struct sk_buff *skb,
|
|
unsigned int flags);
|
|
extern unsigned int skb_checksum(const struct sk_buff *skb, int offset,
|
|
int len, unsigned int csum);
|
|
extern int skb_copy_bits(const struct sk_buff *skb, int offset,
|
|
void *to, int len);
|
|
extern int skb_store_bits(const struct sk_buff *skb, int offset,
|
|
void *from, int len);
|
|
extern unsigned int skb_copy_and_csum_bits(const struct sk_buff *skb,
|
|
int offset, u8 *to, int len,
|
|
unsigned int csum);
|
|
extern void skb_copy_and_csum_dev(const struct sk_buff *skb, u8 *to);
|
|
extern void skb_split(struct sk_buff *skb,
|
|
struct sk_buff *skb1, const u32 len);
|
|
|
|
extern void skb_release_data(struct sk_buff *skb);
|
|
|
|
static inline void *skb_header_pointer(const struct sk_buff *skb, int offset,
|
|
int len, void *buffer)
|
|
{
|
|
int hlen = skb_headlen(skb);
|
|
|
|
if (hlen - offset >= len)
|
|
return skb->data + offset;
|
|
|
|
if (skb_copy_bits(skb, offset, buffer, len) < 0)
|
|
return NULL;
|
|
|
|
return buffer;
|
|
}
|
|
|
|
extern void skb_init(void);
|
|
extern void skb_add_mtu(int mtu);
|
|
|
|
/**
|
|
* skb_get_timestamp - get timestamp from a skb
|
|
* @skb: skb to get stamp from
|
|
* @stamp: pointer to struct timeval to store stamp in
|
|
*
|
|
* Timestamps are stored in the skb as offsets to a base timestamp.
|
|
* This function converts the offset back to a struct timeval and stores
|
|
* it in stamp.
|
|
*/
|
|
static inline void skb_get_timestamp(const struct sk_buff *skb, struct timeval *stamp)
|
|
{
|
|
stamp->tv_sec = skb->tstamp.off_sec;
|
|
stamp->tv_usec = skb->tstamp.off_usec;
|
|
}
|
|
|
|
/**
|
|
* skb_set_timestamp - set timestamp of a skb
|
|
* @skb: skb to set stamp of
|
|
* @stamp: pointer to struct timeval to get stamp from
|
|
*
|
|
* Timestamps are stored in the skb as offsets to a base timestamp.
|
|
* This function converts a struct timeval to an offset and stores
|
|
* it in the skb.
|
|
*/
|
|
static inline void skb_set_timestamp(struct sk_buff *skb, const struct timeval *stamp)
|
|
{
|
|
skb->tstamp.off_sec = stamp->tv_sec;
|
|
skb->tstamp.off_usec = stamp->tv_usec;
|
|
}
|
|
|
|
extern void __net_timestamp(struct sk_buff *skb);
|
|
|
|
extern unsigned int __skb_checksum_complete(struct sk_buff *skb);
|
|
|
|
/**
|
|
* skb_checksum_complete - Calculate checksum of an entire packet
|
|
* @skb: packet to process
|
|
*
|
|
* This function calculates the checksum over the entire packet plus
|
|
* the value of skb->csum. The latter can be used to supply the
|
|
* checksum of a pseudo header as used by TCP/UDP. It returns the
|
|
* checksum.
|
|
*
|
|
* For protocols that contain complete checksums such as ICMP/TCP/UDP,
|
|
* this function can be used to verify that checksum on received
|
|
* packets. In that case the function should return zero if the
|
|
* checksum is correct. In particular, this function will return zero
|
|
* if skb->ip_summed is CHECKSUM_UNNECESSARY which indicates that the
|
|
* hardware has already verified the correctness of the checksum.
|
|
*/
|
|
static inline unsigned int skb_checksum_complete(struct sk_buff *skb)
|
|
{
|
|
return skb->ip_summed != CHECKSUM_UNNECESSARY &&
|
|
__skb_checksum_complete(skb);
|
|
}
|
|
|
|
#ifdef CONFIG_NETFILTER
|
|
static inline void nf_conntrack_put(struct nf_conntrack *nfct)
|
|
{
|
|
if (nfct && atomic_dec_and_test(&nfct->use))
|
|
nfct->destroy(nfct);
|
|
}
|
|
static inline void nf_conntrack_get(struct nf_conntrack *nfct)
|
|
{
|
|
if (nfct)
|
|
atomic_inc(&nfct->use);
|
|
}
|
|
#if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
|
|
static inline void nf_conntrack_get_reasm(struct sk_buff *skb)
|
|
{
|
|
if (skb)
|
|
atomic_inc(&skb->users);
|
|
}
|
|
static inline void nf_conntrack_put_reasm(struct sk_buff *skb)
|
|
{
|
|
if (skb)
|
|
kfree_skb(skb);
|
|
}
|
|
#endif
|
|
#ifdef CONFIG_BRIDGE_NETFILTER
|
|
static inline void nf_bridge_put(struct nf_bridge_info *nf_bridge)
|
|
{
|
|
if (nf_bridge && atomic_dec_and_test(&nf_bridge->use))
|
|
kfree(nf_bridge);
|
|
}
|
|
static inline void nf_bridge_get(struct nf_bridge_info *nf_bridge)
|
|
{
|
|
if (nf_bridge)
|
|
atomic_inc(&nf_bridge->use);
|
|
}
|
|
#endif /* CONFIG_BRIDGE_NETFILTER */
|
|
static inline void nf_reset(struct sk_buff *skb)
|
|
{
|
|
nf_conntrack_put(skb->nfct);
|
|
skb->nfct = NULL;
|
|
#if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
|
|
nf_conntrack_put_reasm(skb->nfct_reasm);
|
|
skb->nfct_reasm = NULL;
|
|
#endif
|
|
#ifdef CONFIG_BRIDGE_NETFILTER
|
|
nf_bridge_put(skb->nf_bridge);
|
|
skb->nf_bridge = NULL;
|
|
#endif
|
|
}
|
|
|
|
#else /* CONFIG_NETFILTER */
|
|
static inline void nf_reset(struct sk_buff *skb) {}
|
|
#endif /* CONFIG_NETFILTER */
|
|
|
|
#endif /* __KERNEL__ */
|
|
#endif /* _LINUX_SKBUFF_H */
|