2090 lines
58 KiB
C
2090 lines
58 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/kernel.h>
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#include <linux/kmemcheck.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/net.h>
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#include <linux/textsearch.h>
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#include <net/checksum.h>
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#include <linux/rcupdate.h>
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#include <linux/dmaengine.h>
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#include <linux/hrtimer.h>
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/* Don't change this without changing skb_csum_unnecessary! */
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#define CHECKSUM_NONE 0
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#define CHECKSUM_UNNECESSARY 1
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#define CHECKSUM_COMPLETE 2
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#define CHECKSUM_PARTIAL 3
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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_WITH_OVERHEAD(X) \
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((X) - SKB_DATA_ALIGN(sizeof(struct skb_shared_info)))
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#define SKB_MAX_ORDER(X, ORDER) \
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SKB_WITH_OVERHEAD((PAGE_SIZE << (ORDER)) - (X))
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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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* COMPLETE: 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 COMPLETE,
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* not UNNECESSARY.
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*
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* PARTIAL: identical to the case for output below. This may occur
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* on a packet received directly from another Linux OS, e.g.,
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* a virtualised Linux kernel on the same host. The packet can
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* be treated in the same way as UNNECESSARY except that on
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* output (i.e., forwarding) the checksum must be filled in
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* by the OS or the hardware.
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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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* PARTIAL: device is required to csum packet as seen by hard_start_xmit
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* from skb->csum_start to the end and to record the checksum
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* at skb->csum_start + skb->csum_offset.
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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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* NETIF_F_IPV6_CSUM about as dumb as the last one but does IPv6 instead.
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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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struct scatterlist;
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struct pipe_inode_info;
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#if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
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struct nf_conntrack {
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atomic_t use;
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};
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#endif
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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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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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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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__u32 page_offset;
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__u32 size;
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};
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#define HAVE_HW_TIME_STAMP
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/**
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* struct skb_shared_hwtstamps - hardware time stamps
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* @hwtstamp: hardware time stamp transformed into duration
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* since arbitrary point in time
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* @syststamp: hwtstamp transformed to system time base
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*
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* Software time stamps generated by ktime_get_real() are stored in
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* skb->tstamp. The relation between the different kinds of time
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* stamps is as follows:
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*
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* syststamp and tstamp can be compared against each other in
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* arbitrary combinations. The accuracy of a
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* syststamp/tstamp/"syststamp from other device" comparison is
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* limited by the accuracy of the transformation into system time
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* base. This depends on the device driver and its underlying
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* hardware.
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*
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* hwtstamps can only be compared against other hwtstamps from
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* the same device.
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*
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* This structure is attached to packets as part of the
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* &skb_shared_info. Use skb_hwtstamps() to get a pointer.
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*/
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struct skb_shared_hwtstamps {
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ktime_t hwtstamp;
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ktime_t syststamp;
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};
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/**
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* struct skb_shared_tx - instructions for time stamping of outgoing packets
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* @hardware: generate hardware time stamp
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* @software: generate software time stamp
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* @in_progress: device driver is going to provide
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* hardware time stamp
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* @flags: all shared_tx flags
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*
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* These flags are attached to packets as part of the
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* &skb_shared_info. Use skb_tx() to get a pointer.
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*/
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union skb_shared_tx {
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struct {
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__u8 hardware:1,
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software:1,
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in_progress:1;
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};
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__u8 flags;
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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 gso_size;
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#ifdef CONFIG_HAS_DMA
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dma_addr_t dma_head;
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#endif
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/* Warning: this field is not always filled in (UFO)! */
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unsigned short gso_segs;
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unsigned short gso_type;
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__be32 ip6_frag_id;
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union skb_shared_tx tx_flags;
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struct sk_buff *frag_list;
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struct skb_shared_hwtstamps hwtstamps;
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skb_frag_t frags[MAX_SKB_FRAGS];
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#ifdef CONFIG_HAS_DMA
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dma_addr_t dma_maps[MAX_SKB_FRAGS];
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#endif
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/* Intermediate layers must ensure that destructor_arg
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* remains valid until skb destructor */
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void * destructor_arg;
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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. A clone of a headerless skb holds the length of
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* the header in skb->hdr_len.
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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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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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enum {
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SKB_GSO_TCPV4 = 1 << 0,
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SKB_GSO_UDP = 1 << 1,
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/* This indicates the skb is from an untrusted source. */
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SKB_GSO_DODGY = 1 << 2,
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/* This indicates the tcp segment has CWR set. */
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SKB_GSO_TCP_ECN = 1 << 3,
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SKB_GSO_TCPV6 = 1 << 4,
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SKB_GSO_FCOE = 1 << 5,
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};
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#if BITS_PER_LONG > 32
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#define NET_SKBUFF_DATA_USES_OFFSET 1
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#endif
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#ifdef NET_SKBUFF_DATA_USES_OFFSET
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typedef unsigned int sk_buff_data_t;
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#else
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typedef unsigned char *sk_buff_data_t;
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#endif
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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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* @transport_header: Transport layer header
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* @network_header: Network layer header
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* @mac_header: Link layer header
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* @_skb_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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* @hdr_len: writable header length of cloned skb
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* @csum: Checksum (must include start/offset pair)
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* @csum_start: Offset from skb->head where checksumming should start
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* @csum_offset: Offset from csum_start where checksum should be stored
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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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* @mark: Generic packet mark
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* @nfct: Associated connection, if any
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* @ipvs_property: skbuff is owned by ipvs
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* @peeked: this packet has been seen already, so stats have been
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* done for it, don't do them again
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* @nf_trace: netfilter packet trace flag
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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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* @iif: ifindex of device we arrived on
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* @queue_mapping: Queue mapping for multiqueue devices
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* @tc_index: Traffic control index
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* @tc_verd: traffic control verdict
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* @ndisc_nodetype: router type (from link layer)
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* @dma_cookie: a cookie to one of several possible DMA operations
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* done by skb DMA functions
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* @secmark: security marking
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* @vlan_tci: vlan tag control information
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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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ktime_t tstamp;
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struct net_device *dev;
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unsigned long _skb_dst;
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#ifdef CONFIG_XFRM
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struct sec_path *sp;
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#endif
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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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__u16 mac_len,
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hdr_len;
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union {
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__wsum csum;
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struct {
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__u16 csum_start;
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__u16 csum_offset;
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};
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};
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__u32 priority;
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kmemcheck_bitfield_begin(flags1);
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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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peeked:1,
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nf_trace:1;
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__be16 protocol:16;
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kmemcheck_bitfield_end(flags1);
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void (*destructor)(struct sk_buff *skb);
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#if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
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struct nf_conntrack *nfct;
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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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int iif;
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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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kmemcheck_bitfield_begin(flags2);
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__u16 queue_mapping:16;
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#ifdef CONFIG_IPV6_NDISC_NODETYPE
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__u8 ndisc_nodetype:2;
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#endif
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kmemcheck_bitfield_end(flags2);
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/* 0/14 bit hole */
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#ifdef CONFIG_NET_DMA
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dma_cookie_t dma_cookie;
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#endif
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#ifdef CONFIG_NETWORK_SECMARK
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__u32 secmark;
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#endif
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__u32 mark;
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__u16 vlan_tci;
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sk_buff_data_t transport_header;
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sk_buff_data_t network_header;
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sk_buff_data_t mac_header;
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/* These elements must be at the end, see alloc_skb() for details. */
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sk_buff_data_t tail;
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sk_buff_data_t end;
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unsigned char *head,
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*data;
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unsigned int truesize;
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atomic_t users;
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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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#ifdef CONFIG_HAS_DMA
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#include <linux/dma-mapping.h>
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extern int skb_dma_map(struct device *dev, struct sk_buff *skb,
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enum dma_data_direction dir);
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extern void skb_dma_unmap(struct device *dev, struct sk_buff *skb,
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enum dma_data_direction dir);
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#endif
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static inline struct dst_entry *skb_dst(const struct sk_buff *skb)
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{
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return (struct dst_entry *)skb->_skb_dst;
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}
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static inline void skb_dst_set(struct sk_buff *skb, struct dst_entry *dst)
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{
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skb->_skb_dst = (unsigned long)dst;
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}
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static inline struct rtable *skb_rtable(const struct sk_buff *skb)
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{
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return (struct rtable *)skb_dst(skb);
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}
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extern void kfree_skb(struct sk_buff *skb);
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extern void consume_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, int node);
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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, -1);
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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, -1);
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}
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extern int skb_recycle_check(struct sk_buff *skb, int skb_size);
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extern struct sk_buff *skb_morph(struct sk_buff *dst, struct sk_buff *src);
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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 int skb_to_sgvec(struct sk_buff *skb,
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struct scatterlist *sg, int offset,
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int len);
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extern int skb_cow_data(struct sk_buff *skb, int tailbits,
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struct sk_buff **trailer);
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extern int skb_pad(struct sk_buff *skb, int pad);
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#define dev_kfree_skb(a) consume_skb(a)
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#define dev_consume_skb(a) kfree_skb_clean(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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|
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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;
|
|
struct sk_buff *root_skb;
|
|
struct sk_buff *cur_skb;
|
|
__u8 *frag_data;
|
|
};
|
|
|
|
extern void skb_prepare_seq_read(struct sk_buff *skb,
|
|
unsigned int from, unsigned int to,
|
|
struct skb_seq_state *st);
|
|
extern unsigned int skb_seq_read(unsigned int consumed, const u8 **data,
|
|
struct skb_seq_state *st);
|
|
extern void skb_abort_seq_read(struct skb_seq_state *st);
|
|
|
|
extern unsigned int skb_find_text(struct sk_buff *skb, unsigned int from,
|
|
unsigned int to, struct ts_config *config,
|
|
struct ts_state *state);
|
|
|
|
#ifdef NET_SKBUFF_DATA_USES_OFFSET
|
|
static inline unsigned char *skb_end_pointer(const struct sk_buff *skb)
|
|
{
|
|
return skb->head + skb->end;
|
|
}
|
|
#else
|
|
static inline unsigned char *skb_end_pointer(const struct sk_buff *skb)
|
|
{
|
|
return skb->end;
|
|
}
|
|
#endif
|
|
|
|
/* Internal */
|
|
#define skb_shinfo(SKB) ((struct skb_shared_info *)(skb_end_pointer(SKB)))
|
|
|
|
static inline struct skb_shared_hwtstamps *skb_hwtstamps(struct sk_buff *skb)
|
|
{
|
|
return &skb_shinfo(skb)->hwtstamps;
|
|
}
|
|
|
|
static inline union skb_shared_tx *skb_tx(struct sk_buff *skb)
|
|
{
|
|
return &skb_shinfo(skb)->tx_flags;
|
|
}
|
|
|
|
/**
|
|
* skb_queue_empty - check if a queue is empty
|
|
* @list: queue head
|
|
*
|
|
* Returns true if the queue is empty, false otherwise.
|
|
*/
|
|
static inline int skb_queue_empty(const struct sk_buff_head *list)
|
|
{
|
|
return list->next == (struct sk_buff *)list;
|
|
}
|
|
|
|
/**
|
|
* skb_queue_is_last - check if skb is the last entry in the queue
|
|
* @list: queue head
|
|
* @skb: buffer
|
|
*
|
|
* Returns true if @skb is the last buffer on the list.
|
|
*/
|
|
static inline bool skb_queue_is_last(const struct sk_buff_head *list,
|
|
const struct sk_buff *skb)
|
|
{
|
|
return (skb->next == (struct sk_buff *) list);
|
|
}
|
|
|
|
/**
|
|
* skb_queue_is_first - check if skb is the first entry in the queue
|
|
* @list: queue head
|
|
* @skb: buffer
|
|
*
|
|
* Returns true if @skb is the first buffer on the list.
|
|
*/
|
|
static inline bool skb_queue_is_first(const struct sk_buff_head *list,
|
|
const struct sk_buff *skb)
|
|
{
|
|
return (skb->prev == (struct sk_buff *) list);
|
|
}
|
|
|
|
/**
|
|
* skb_queue_next - return the next packet in the queue
|
|
* @list: queue head
|
|
* @skb: current buffer
|
|
*
|
|
* Return the next packet in @list after @skb. It is only valid to
|
|
* call this if skb_queue_is_last() evaluates to false.
|
|
*/
|
|
static inline struct sk_buff *skb_queue_next(const struct sk_buff_head *list,
|
|
const struct sk_buff *skb)
|
|
{
|
|
/* This BUG_ON may seem severe, but if we just return then we
|
|
* are going to dereference garbage.
|
|
*/
|
|
BUG_ON(skb_queue_is_last(list, skb));
|
|
return skb->next;
|
|
}
|
|
|
|
/**
|
|
* skb_queue_prev - return the prev packet in the queue
|
|
* @list: queue head
|
|
* @skb: current buffer
|
|
*
|
|
* Return the prev packet in @list before @skb. It is only valid to
|
|
* call this if skb_queue_is_first() evaluates to false.
|
|
*/
|
|
static inline struct sk_buff *skb_queue_prev(const struct sk_buff_head *list,
|
|
const struct sk_buff *skb)
|
|
{
|
|
/* This BUG_ON may seem severe, but if we just return then we
|
|
* are going to dereference garbage.
|
|
*/
|
|
BUG_ON(skb_queue_is_first(list, skb));
|
|
return skb->prev;
|
|
}
|
|
|
|
/**
|
|
* skb_get - reference buffer
|
|
* @skb: buffer to reference
|
|
*
|
|
* Makes another reference to a socket buffer and returns a pointer
|
|
* to the buffer.
|
|
*/
|
|
static inline struct sk_buff *skb_get(struct sk_buff *skb)
|
|
{
|
|
atomic_inc(&skb->users);
|
|
return skb;
|
|
}
|
|
|
|
/*
|
|
* If users == 1, we are the only owner and are can avoid redundant
|
|
* atomic change.
|
|
*/
|
|
|
|
/**
|
|
* skb_cloned - is the buffer a clone
|
|
* @skb: buffer to check
|
|
*
|
|
* Returns true if the buffer was generated with skb_clone() and is
|
|
* one of multiple shared copies of the buffer. Cloned buffers are
|
|
* shared data so must not be written to under normal circumstances.
|
|
*/
|
|
static inline int skb_cloned(const struct sk_buff *skb)
|
|
{
|
|
return skb->cloned &&
|
|
(atomic_read(&skb_shinfo(skb)->dataref) & SKB_DATAREF_MASK) != 1;
|
|
}
|
|
|
|
/**
|
|
* skb_header_cloned - is the header a clone
|
|
* @skb: buffer to check
|
|
*
|
|
* Returns true if modifying the header part of the buffer requires
|
|
* the data to be copied.
|
|
*/
|
|
static inline int skb_header_cloned(const struct sk_buff *skb)
|
|
{
|
|
int dataref;
|
|
|
|
if (!skb->cloned)
|
|
return 0;
|
|
|
|
dataref = atomic_read(&skb_shinfo(skb)->dataref);
|
|
dataref = (dataref & SKB_DATAREF_MASK) - (dataref >> SKB_DATAREF_SHIFT);
|
|
return dataref != 1;
|
|
}
|
|
|
|
/**
|
|
* skb_header_release - release reference to header
|
|
* @skb: buffer to operate on
|
|
*
|
|
* Drop a reference to the header part of the buffer. This is done
|
|
* by acquiring a payload reference. You must not read from the header
|
|
* part of skb->data after this.
|
|
*/
|
|
static inline void skb_header_release(struct sk_buff *skb)
|
|
{
|
|
BUG_ON(skb->nohdr);
|
|
skb->nohdr = 1;
|
|
atomic_add(1 << SKB_DATAREF_SHIFT, &skb_shinfo(skb)->dataref);
|
|
}
|
|
|
|
/**
|
|
* skb_shared - is the buffer shared
|
|
* @skb: buffer to check
|
|
*
|
|
* Returns true if more than one person has a reference to this
|
|
* buffer.
|
|
*/
|
|
static inline int skb_shared(const struct sk_buff *skb)
|
|
{
|
|
return atomic_read(&skb->users) != 1;
|
|
}
|
|
|
|
/**
|
|
* skb_share_check - check if buffer is shared and if so clone it
|
|
* @skb: buffer to check
|
|
* @pri: priority for memory allocation
|
|
*
|
|
* If the buffer is shared the buffer is cloned and the old copy
|
|
* drops a reference. A new clone with a single reference is returned.
|
|
* If the buffer is not shared the original buffer is returned. When
|
|
* being called from interrupt status or with spinlocks held pri must
|
|
* be GFP_ATOMIC.
|
|
*
|
|
* NULL is returned on a memory allocation failure.
|
|
*/
|
|
static inline struct sk_buff *skb_share_check(struct sk_buff *skb,
|
|
gfp_t pri)
|
|
{
|
|
might_sleep_if(pri & __GFP_WAIT);
|
|
if (skb_shared(skb)) {
|
|
struct sk_buff *nskb = skb_clone(skb, pri);
|
|
kfree_skb(skb);
|
|
skb = nskb;
|
|
}
|
|
return skb;
|
|
}
|
|
|
|
/*
|
|
* Copy shared buffers into a new sk_buff. We effectively do COW on
|
|
* packets to handle cases where we have a local reader and forward
|
|
* and a couple of other messy ones. The normal one is tcpdumping
|
|
* a packet thats being forwarded.
|
|
*/
|
|
|
|
/**
|
|
* skb_unshare - make a copy of a shared buffer
|
|
* @skb: buffer to check
|
|
* @pri: priority for memory allocation
|
|
*
|
|
* 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;
|
|
}
|
|
|
|
/**
|
|
* __skb_queue_head_init - initialize non-spinlock portions of sk_buff_head
|
|
* @list: queue to initialize
|
|
*
|
|
* This initializes only the list and queue length aspects of
|
|
* an sk_buff_head object. This allows to initialize the list
|
|
* aspects of an sk_buff_head without reinitializing things like
|
|
* the spinlock. It can also be used for on-stack sk_buff_head
|
|
* objects where the spinlock is known to not be used.
|
|
*/
|
|
static inline void __skb_queue_head_init(struct sk_buff_head *list)
|
|
{
|
|
list->prev = list->next = (struct sk_buff *)list;
|
|
list->qlen = 0;
|
|
}
|
|
|
|
/*
|
|
* This function creates a split out lock class for each invocation;
|
|
* this is needed for now since a whole lot of users of the skb-queue
|
|
* infrastructure in drivers have different locking usage (in hardirq)
|
|
* than the networking core (in softirq only). In the long run either the
|
|
* network layer or drivers should need annotation to consolidate the
|
|
* main types of usage into 3 classes.
|
|
*/
|
|
static inline void skb_queue_head_init(struct sk_buff_head *list)
|
|
{
|
|
spin_lock_init(&list->lock);
|
|
__skb_queue_head_init(list);
|
|
}
|
|
|
|
static inline void skb_queue_head_init_class(struct sk_buff_head *list,
|
|
struct lock_class_key *class)
|
|
{
|
|
skb_queue_head_init(list);
|
|
lockdep_set_class(&list->lock, class);
|
|
}
|
|
|
|
/*
|
|
* Insert an sk_buff on a list.
|
|
*
|
|
* The "__skb_xxxx()" functions are the non-atomic ones that
|
|
* can only be called with interrupts disabled.
|
|
*/
|
|
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++;
|
|
}
|
|
|
|
static inline void __skb_queue_splice(const struct sk_buff_head *list,
|
|
struct sk_buff *prev,
|
|
struct sk_buff *next)
|
|
{
|
|
struct sk_buff *first = list->next;
|
|
struct sk_buff *last = list->prev;
|
|
|
|
first->prev = prev;
|
|
prev->next = first;
|
|
|
|
last->next = next;
|
|
next->prev = last;
|
|
}
|
|
|
|
/**
|
|
* skb_queue_splice - join two skb lists, this is designed for stacks
|
|
* @list: the new list to add
|
|
* @head: the place to add it in the first list
|
|
*/
|
|
static inline void skb_queue_splice(const struct sk_buff_head *list,
|
|
struct sk_buff_head *head)
|
|
{
|
|
if (!skb_queue_empty(list)) {
|
|
__skb_queue_splice(list, (struct sk_buff *) head, head->next);
|
|
head->qlen += list->qlen;
|
|
}
|
|
}
|
|
|
|
/**
|
|
* skb_queue_splice - join two skb lists and reinitialise the emptied list
|
|
* @list: the new list to add
|
|
* @head: the place to add it in the first list
|
|
*
|
|
* The list at @list is reinitialised
|
|
*/
|
|
static inline void skb_queue_splice_init(struct sk_buff_head *list,
|
|
struct sk_buff_head *head)
|
|
{
|
|
if (!skb_queue_empty(list)) {
|
|
__skb_queue_splice(list, (struct sk_buff *) head, head->next);
|
|
head->qlen += list->qlen;
|
|
__skb_queue_head_init(list);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* skb_queue_splice_tail - join two skb lists, each list being a queue
|
|
* @list: the new list to add
|
|
* @head: the place to add it in the first list
|
|
*/
|
|
static inline void skb_queue_splice_tail(const struct sk_buff_head *list,
|
|
struct sk_buff_head *head)
|
|
{
|
|
if (!skb_queue_empty(list)) {
|
|
__skb_queue_splice(list, head->prev, (struct sk_buff *) head);
|
|
head->qlen += list->qlen;
|
|
}
|
|
}
|
|
|
|
/**
|
|
* skb_queue_splice_tail - join two skb lists and reinitialise the emptied list
|
|
* @list: the new list to add
|
|
* @head: the place to add it in the first list
|
|
*
|
|
* Each of the lists is a queue.
|
|
* The list at @list is reinitialised
|
|
*/
|
|
static inline void skb_queue_splice_tail_init(struct sk_buff_head *list,
|
|
struct sk_buff_head *head)
|
|
{
|
|
if (!skb_queue_empty(list)) {
|
|
__skb_queue_splice(list, head->prev, (struct sk_buff *) head);
|
|
head->qlen += list->qlen;
|
|
__skb_queue_head_init(list);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* __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)
|
|
{
|
|
__skb_insert(newsk, prev, prev->next, list);
|
|
}
|
|
|
|
extern void skb_append(struct sk_buff *old, struct sk_buff *newsk,
|
|
struct sk_buff_head *list);
|
|
|
|
static inline void __skb_queue_before(struct sk_buff_head *list,
|
|
struct sk_buff *next,
|
|
struct sk_buff *newsk)
|
|
{
|
|
__skb_insert(newsk, next->prev, next, list);
|
|
}
|
|
|
|
/**
|
|
* __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)
|
|
{
|
|
__skb_queue_before(list, (struct sk_buff *)list, newsk);
|
|
}
|
|
|
|
/*
|
|
* 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;
|
|
}
|
|
|
|
/**
|
|
* __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 *skb = skb_peek(list);
|
|
if (skb)
|
|
__skb_unlink(skb, list);
|
|
return skb;
|
|
}
|
|
|
|
/**
|
|
* __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;
|
|
}
|
|
|
|
extern void skb_add_rx_frag(struct sk_buff *skb, int i, struct page *page,
|
|
int off, int size);
|
|
|
|
#define SKB_PAGE_ASSERT(skb) BUG_ON(skb_shinfo(skb)->nr_frags)
|
|
#define SKB_FRAG_ASSERT(skb) BUG_ON(skb_has_frags(skb))
|
|
#define SKB_LINEAR_ASSERT(skb) BUG_ON(skb_is_nonlinear(skb))
|
|
|
|
#ifdef NET_SKBUFF_DATA_USES_OFFSET
|
|
static inline unsigned char *skb_tail_pointer(const struct sk_buff *skb)
|
|
{
|
|
return skb->head + skb->tail;
|
|
}
|
|
|
|
static inline void skb_reset_tail_pointer(struct sk_buff *skb)
|
|
{
|
|
skb->tail = skb->data - skb->head;
|
|
}
|
|
|
|
static inline void skb_set_tail_pointer(struct sk_buff *skb, const int offset)
|
|
{
|
|
skb_reset_tail_pointer(skb);
|
|
skb->tail += offset;
|
|
}
|
|
#else /* NET_SKBUFF_DATA_USES_OFFSET */
|
|
static inline unsigned char *skb_tail_pointer(const struct sk_buff *skb)
|
|
{
|
|
return skb->tail;
|
|
}
|
|
|
|
static inline void skb_reset_tail_pointer(struct sk_buff *skb)
|
|
{
|
|
skb->tail = skb->data;
|
|
}
|
|
|
|
static inline void skb_set_tail_pointer(struct sk_buff *skb, const int offset)
|
|
{
|
|
skb->tail = skb->data + offset;
|
|
}
|
|
|
|
#endif /* NET_SKBUFF_DATA_USES_OFFSET */
|
|
|
|
/*
|
|
* Add data to an sk_buff
|
|
*/
|
|
extern unsigned char *skb_put(struct sk_buff *skb, unsigned int len);
|
|
static inline unsigned char *__skb_put(struct sk_buff *skb, unsigned int len)
|
|
{
|
|
unsigned char *tmp = skb_tail_pointer(skb);
|
|
SKB_LINEAR_ASSERT(skb);
|
|
skb->tail += len;
|
|
skb->len += len;
|
|
return tmp;
|
|
}
|
|
|
|
extern unsigned char *skb_push(struct sk_buff *skb, unsigned int len);
|
|
static inline unsigned char *__skb_push(struct sk_buff *skb, unsigned int len)
|
|
{
|
|
skb->data -= len;
|
|
skb->len += len;
|
|
return skb->data;
|
|
}
|
|
|
|
extern unsigned char *skb_pull(struct sk_buff *skb, unsigned int len);
|
|
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;
|
|
}
|
|
|
|
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 unsigned 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;
|
|
}
|
|
|
|
#ifdef NET_SKBUFF_DATA_USES_OFFSET
|
|
static inline unsigned char *skb_transport_header(const struct sk_buff *skb)
|
|
{
|
|
return skb->head + skb->transport_header;
|
|
}
|
|
|
|
static inline void skb_reset_transport_header(struct sk_buff *skb)
|
|
{
|
|
skb->transport_header = skb->data - skb->head;
|
|
}
|
|
|
|
static inline void skb_set_transport_header(struct sk_buff *skb,
|
|
const int offset)
|
|
{
|
|
skb_reset_transport_header(skb);
|
|
skb->transport_header += offset;
|
|
}
|
|
|
|
static inline unsigned char *skb_network_header(const struct sk_buff *skb)
|
|
{
|
|
return skb->head + skb->network_header;
|
|
}
|
|
|
|
static inline void skb_reset_network_header(struct sk_buff *skb)
|
|
{
|
|
skb->network_header = skb->data - skb->head;
|
|
}
|
|
|
|
static inline void skb_set_network_header(struct sk_buff *skb, const int offset)
|
|
{
|
|
skb_reset_network_header(skb);
|
|
skb->network_header += offset;
|
|
}
|
|
|
|
static inline unsigned char *skb_mac_header(const struct sk_buff *skb)
|
|
{
|
|
return skb->head + skb->mac_header;
|
|
}
|
|
|
|
static inline int skb_mac_header_was_set(const struct sk_buff *skb)
|
|
{
|
|
return skb->mac_header != ~0U;
|
|
}
|
|
|
|
static inline void skb_reset_mac_header(struct sk_buff *skb)
|
|
{
|
|
skb->mac_header = skb->data - skb->head;
|
|
}
|
|
|
|
static inline void skb_set_mac_header(struct sk_buff *skb, const int offset)
|
|
{
|
|
skb_reset_mac_header(skb);
|
|
skb->mac_header += offset;
|
|
}
|
|
|
|
#else /* NET_SKBUFF_DATA_USES_OFFSET */
|
|
|
|
static inline unsigned char *skb_transport_header(const struct sk_buff *skb)
|
|
{
|
|
return skb->transport_header;
|
|
}
|
|
|
|
static inline void skb_reset_transport_header(struct sk_buff *skb)
|
|
{
|
|
skb->transport_header = skb->data;
|
|
}
|
|
|
|
static inline void skb_set_transport_header(struct sk_buff *skb,
|
|
const int offset)
|
|
{
|
|
skb->transport_header = skb->data + offset;
|
|
}
|
|
|
|
static inline unsigned char *skb_network_header(const struct sk_buff *skb)
|
|
{
|
|
return skb->network_header;
|
|
}
|
|
|
|
static inline void skb_reset_network_header(struct sk_buff *skb)
|
|
{
|
|
skb->network_header = skb->data;
|
|
}
|
|
|
|
static inline void skb_set_network_header(struct sk_buff *skb, const int offset)
|
|
{
|
|
skb->network_header = skb->data + offset;
|
|
}
|
|
|
|
static inline unsigned char *skb_mac_header(const struct sk_buff *skb)
|
|
{
|
|
return skb->mac_header;
|
|
}
|
|
|
|
static inline int skb_mac_header_was_set(const struct sk_buff *skb)
|
|
{
|
|
return skb->mac_header != NULL;
|
|
}
|
|
|
|
static inline void skb_reset_mac_header(struct sk_buff *skb)
|
|
{
|
|
skb->mac_header = skb->data;
|
|
}
|
|
|
|
static inline void skb_set_mac_header(struct sk_buff *skb, const int offset)
|
|
{
|
|
skb->mac_header = skb->data + offset;
|
|
}
|
|
#endif /* NET_SKBUFF_DATA_USES_OFFSET */
|
|
|
|
static inline int skb_transport_offset(const struct sk_buff *skb)
|
|
{
|
|
return skb_transport_header(skb) - skb->data;
|
|
}
|
|
|
|
static inline u32 skb_network_header_len(const struct sk_buff *skb)
|
|
{
|
|
return skb->transport_header - skb->network_header;
|
|
}
|
|
|
|
static inline int skb_network_offset(const struct sk_buff *skb)
|
|
{
|
|
return skb_network_header(skb) - skb->data;
|
|
}
|
|
|
|
/*
|
|
* 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(skb, 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
|
|
|
|
/*
|
|
* The networking layer reserves some headroom in skb data (via
|
|
* dev_alloc_skb). This is used to avoid having to reallocate skb data when
|
|
* the header has to grow. In the default case, if the header has to grow
|
|
* 32 bytes or less we avoid the reallocation.
|
|
*
|
|
* Unfortunately this headroom changes the DMA alignment of the resulting
|
|
* network packet. As for NET_IP_ALIGN, this unaligned DMA is expensive
|
|
* on some architectures. An architecture can override this value,
|
|
* perhaps setting it to a cacheline in size (since that will maintain
|
|
* cacheline alignment of the DMA). It must be a power of 2.
|
|
*
|
|
* Various parts of the networking layer expect at least 32 bytes of
|
|
* headroom, you should not reduce this.
|
|
*/
|
|
#ifndef NET_SKB_PAD
|
|
#define NET_SKB_PAD 32
|
|
#endif
|
|
|
|
extern int ___pskb_trim(struct sk_buff *skb, unsigned int len);
|
|
|
|
static inline void __skb_trim(struct sk_buff *skb, unsigned int len)
|
|
{
|
|
if (unlikely(skb->data_len)) {
|
|
WARN_ON(1);
|
|
return;
|
|
}
|
|
skb->len = len;
|
|
skb_set_tail_pointer(skb, len);
|
|
}
|
|
|
|
extern void skb_trim(struct sk_buff *skb, unsigned int len);
|
|
|
|
static inline int __pskb_trim(struct sk_buff *skb, unsigned int len)
|
|
{
|
|
if (skb->data_len)
|
|
return ___pskb_trim(skb, len);
|
|
__skb_trim(skb, len);
|
|
return 0;
|
|
}
|
|
|
|
static inline int pskb_trim(struct sk_buff *skb, unsigned int len)
|
|
{
|
|
return (len < skb->len) ? __pskb_trim(skb, len) : 0;
|
|
}
|
|
|
|
/**
|
|
* pskb_trim_unique - remove end from a paged unique (not cloned) buffer
|
|
* @skb: buffer to alter
|
|
* @len: new length
|
|
*
|
|
* This is identical to pskb_trim except that the caller knows that
|
|
* the skb is not cloned so we should never get an error due to out-
|
|
* of-memory.
|
|
*/
|
|
static inline void pskb_trim_unique(struct sk_buff *skb, unsigned int len)
|
|
{
|
|
int err = pskb_trim(skb, len);
|
|
BUG_ON(err);
|
|
}
|
|
|
|
/**
|
|
* 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);
|
|
}
|
|
|
|
/**
|
|
* __dev_alloc_skb - allocate an skbuff for receiving
|
|
* @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 if 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 + NET_SKB_PAD, gfp_mask);
|
|
if (likely(skb))
|
|
skb_reserve(skb, NET_SKB_PAD);
|
|
return skb;
|
|
}
|
|
|
|
extern struct sk_buff *dev_alloc_skb(unsigned int length);
|
|
|
|
extern struct sk_buff *__netdev_alloc_skb(struct net_device *dev,
|
|
unsigned int length, gfp_t gfp_mask);
|
|
|
|
/**
|
|
* netdev_alloc_skb - allocate an skbuff for rx on a specific device
|
|
* @dev: network device to receive on
|
|
* @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 if there is no free memory. Although this function
|
|
* allocates memory it can be called from an interrupt.
|
|
*/
|
|
static inline struct sk_buff *netdev_alloc_skb(struct net_device *dev,
|
|
unsigned int length)
|
|
{
|
|
return __netdev_alloc_skb(dev, length, GFP_ATOMIC);
|
|
}
|
|
|
|
extern struct page *__netdev_alloc_page(struct net_device *dev, gfp_t gfp_mask);
|
|
|
|
/**
|
|
* netdev_alloc_page - allocate a page for ps-rx on a specific device
|
|
* @dev: network device to receive on
|
|
*
|
|
* Allocate a new page node local to the specified device.
|
|
*
|
|
* %NULL is returned if there is no free memory.
|
|
*/
|
|
static inline struct page *netdev_alloc_page(struct net_device *dev)
|
|
{
|
|
return __netdev_alloc_page(dev, GFP_ATOMIC);
|
|
}
|
|
|
|
static inline void netdev_free_page(struct net_device *dev, struct page *page)
|
|
{
|
|
__free_page(page);
|
|
}
|
|
|
|
/**
|
|
* skb_clone_writable - is the header of a clone writable
|
|
* @skb: buffer to check
|
|
* @len: length up to which to write
|
|
*
|
|
* Returns true if modifying the header part of the cloned buffer
|
|
* does not requires the data to be copied.
|
|
*/
|
|
static inline int skb_clone_writable(struct sk_buff *skb, unsigned int len)
|
|
{
|
|
return !skb_header_cloned(skb) &&
|
|
skb_headroom(skb) + len <= skb->hdr_len;
|
|
}
|
|
|
|
static inline int __skb_cow(struct sk_buff *skb, unsigned int headroom,
|
|
int cloned)
|
|
{
|
|
int delta = 0;
|
|
|
|
if (headroom < NET_SKB_PAD)
|
|
headroom = NET_SKB_PAD;
|
|
if (headroom > skb_headroom(skb))
|
|
delta = headroom - skb_headroom(skb);
|
|
|
|
if (delta || cloned)
|
|
return pskb_expand_head(skb, ALIGN(delta, NET_SKB_PAD), 0,
|
|
GFP_ATOMIC);
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* 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)
|
|
{
|
|
return __skb_cow(skb, headroom, skb_cloned(skb));
|
|
}
|
|
|
|
/**
|
|
* skb_cow_head - skb_cow but only making the head writable
|
|
* @skb: buffer to cow
|
|
* @headroom: needed headroom
|
|
*
|
|
* This function is identical to skb_cow except that we replace the
|
|
* skb_cloned check by skb_header_cloned. It should be used when
|
|
* you only need to push on some header and do not need to modify
|
|
* the data.
|
|
*/
|
|
static inline int skb_cow_head(struct sk_buff *skb, unsigned int headroom)
|
|
{
|
|
return __skb_cow(skb, headroom, skb_header_cloned(skb));
|
|
}
|
|
|
|
/**
|
|
* 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. Otherwise it is extended. Returns zero on
|
|
* success. The skb is freed on error.
|
|
*/
|
|
|
|
static inline int skb_padto(struct sk_buff *skb, unsigned int len)
|
|
{
|
|
unsigned int size = skb->len;
|
|
if (likely(size >= len))
|
|
return 0;
|
|
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;
|
|
__wsum 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;
|
|
}
|
|
|
|
static inline int __skb_linearize(struct sk_buff *skb)
|
|
{
|
|
return __pskb_pull_tail(skb, skb->data_len) ? 0 : -ENOMEM;
|
|
}
|
|
|
|
/**
|
|
* skb_linearize - convert paged skb to linear one
|
|
* @skb: buffer to linarize
|
|
*
|
|
* If there is no free memory -ENOMEM is returned, otherwise zero
|
|
* is returned and the old skb data released.
|
|
*/
|
|
static inline int skb_linearize(struct sk_buff *skb)
|
|
{
|
|
return skb_is_nonlinear(skb) ? __skb_linearize(skb) : 0;
|
|
}
|
|
|
|
/**
|
|
* skb_linearize_cow - make sure skb is linear and writable
|
|
* @skb: buffer to process
|
|
*
|
|
* If there is no free memory -ENOMEM is returned, otherwise zero
|
|
* is returned and the old skb data released.
|
|
*/
|
|
static inline int skb_linearize_cow(struct sk_buff *skb)
|
|
{
|
|
return skb_is_nonlinear(skb) || skb_cloned(skb) ?
|
|
__skb_linearize(skb) : 0;
|
|
}
|
|
|
|
/**
|
|
* 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_COMPLETE 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_COMPLETE)
|
|
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_COMPLETE)
|
|
skb->ip_summed = CHECKSUM_NONE;
|
|
return __pskb_trim(skb, len);
|
|
}
|
|
|
|
#define skb_queue_walk(queue, skb) \
|
|
for (skb = (queue)->next; \
|
|
prefetch(skb->next), (skb != (struct sk_buff *)(queue)); \
|
|
skb = skb->next)
|
|
|
|
#define skb_queue_walk_safe(queue, skb, tmp) \
|
|
for (skb = (queue)->next, tmp = skb->next; \
|
|
skb != (struct sk_buff *)(queue); \
|
|
skb = tmp, tmp = skb->next)
|
|
|
|
#define skb_queue_walk_from(queue, skb) \
|
|
for (; prefetch(skb->next), (skb != (struct sk_buff *)(queue)); \
|
|
skb = skb->next)
|
|
|
|
#define skb_queue_walk_from_safe(queue, skb, tmp) \
|
|
for (tmp = skb->next; \
|
|
skb != (struct sk_buff *)(queue); \
|
|
skb = tmp, tmp = skb->next)
|
|
|
|
#define skb_queue_reverse_walk(queue, skb) \
|
|
for (skb = (queue)->prev; \
|
|
prefetch(skb->prev), (skb != (struct sk_buff *)(queue)); \
|
|
skb = skb->prev)
|
|
|
|
|
|
static inline bool skb_has_frags(const struct sk_buff *skb)
|
|
{
|
|
return skb_shinfo(skb)->frag_list != NULL;
|
|
}
|
|
|
|
static inline void skb_frag_list_init(struct sk_buff *skb)
|
|
{
|
|
skb_shinfo(skb)->frag_list = NULL;
|
|
}
|
|
|
|
static inline void skb_frag_add_head(struct sk_buff *skb, struct sk_buff *frag)
|
|
{
|
|
frag->next = skb_shinfo(skb)->frag_list;
|
|
skb_shinfo(skb)->frag_list = frag;
|
|
}
|
|
|
|
#define skb_walk_frags(skb, iter) \
|
|
for (iter = skb_shinfo(skb)->frag_list; iter; iter = iter->next)
|
|
|
|
extern struct sk_buff *__skb_recv_datagram(struct sock *sk, unsigned flags,
|
|
int *peeked, int *err);
|
|
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 int skb_copy_datagram_from_iovec(struct sk_buff *skb,
|
|
int offset,
|
|
const struct iovec *from,
|
|
int from_offset,
|
|
int len);
|
|
extern int skb_copy_datagram_const_iovec(const struct sk_buff *from,
|
|
int offset,
|
|
const struct iovec *to,
|
|
int to_offset,
|
|
int size);
|
|
extern void skb_free_datagram(struct sock *sk, struct sk_buff *skb);
|
|
extern void skb_free_datagram_locked(struct sock *sk,
|
|
struct sk_buff *skb);
|
|
extern int skb_kill_datagram(struct sock *sk, struct sk_buff *skb,
|
|
unsigned int flags);
|
|
extern __wsum skb_checksum(const struct sk_buff *skb, int offset,
|
|
int len, __wsum csum);
|
|
extern int skb_copy_bits(const struct sk_buff *skb, int offset,
|
|
void *to, int len);
|
|
extern int skb_store_bits(struct sk_buff *skb, int offset,
|
|
const void *from, int len);
|
|
extern __wsum skb_copy_and_csum_bits(const struct sk_buff *skb,
|
|
int offset, u8 *to, int len,
|
|
__wsum csum);
|
|
extern int skb_splice_bits(struct sk_buff *skb,
|
|
unsigned int offset,
|
|
struct pipe_inode_info *pipe,
|
|
unsigned int len,
|
|
unsigned int flags);
|
|
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 int skb_shift(struct sk_buff *tgt, struct sk_buff *skb,
|
|
int shiftlen);
|
|
|
|
extern struct sk_buff *skb_segment(struct sk_buff *skb, int features);
|
|
|
|
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;
|
|
}
|
|
|
|
static inline void skb_copy_from_linear_data(const struct sk_buff *skb,
|
|
void *to,
|
|
const unsigned int len)
|
|
{
|
|
memcpy(to, skb->data, len);
|
|
}
|
|
|
|
static inline void skb_copy_from_linear_data_offset(const struct sk_buff *skb,
|
|
const int offset, void *to,
|
|
const unsigned int len)
|
|
{
|
|
memcpy(to, skb->data + offset, len);
|
|
}
|
|
|
|
static inline void skb_copy_to_linear_data(struct sk_buff *skb,
|
|
const void *from,
|
|
const unsigned int len)
|
|
{
|
|
memcpy(skb->data, from, len);
|
|
}
|
|
|
|
static inline void skb_copy_to_linear_data_offset(struct sk_buff *skb,
|
|
const int offset,
|
|
const void *from,
|
|
const unsigned int len)
|
|
{
|
|
memcpy(skb->data + offset, from, len);
|
|
}
|
|
|
|
extern void skb_init(void);
|
|
|
|
static inline ktime_t skb_get_ktime(const struct sk_buff *skb)
|
|
{
|
|
return skb->tstamp;
|
|
}
|
|
|
|
/**
|
|
* 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 = ktime_to_timeval(skb->tstamp);
|
|
}
|
|
|
|
static inline void skb_get_timestampns(const struct sk_buff *skb,
|
|
struct timespec *stamp)
|
|
{
|
|
*stamp = ktime_to_timespec(skb->tstamp);
|
|
}
|
|
|
|
static inline void __net_timestamp(struct sk_buff *skb)
|
|
{
|
|
skb->tstamp = ktime_get_real();
|
|
}
|
|
|
|
static inline ktime_t net_timedelta(ktime_t t)
|
|
{
|
|
return ktime_sub(ktime_get_real(), t);
|
|
}
|
|
|
|
static inline ktime_t net_invalid_timestamp(void)
|
|
{
|
|
return ktime_set(0, 0);
|
|
}
|
|
|
|
/**
|
|
* skb_tstamp_tx - queue clone of skb with send time stamps
|
|
* @orig_skb: the original outgoing packet
|
|
* @hwtstamps: hardware time stamps, may be NULL if not available
|
|
*
|
|
* If the skb has a socket associated, then this function clones the
|
|
* skb (thus sharing the actual data and optional structures), stores
|
|
* the optional hardware time stamping information (if non NULL) or
|
|
* generates a software time stamp (otherwise), then queues the clone
|
|
* to the error queue of the socket. Errors are silently ignored.
|
|
*/
|
|
extern void skb_tstamp_tx(struct sk_buff *orig_skb,
|
|
struct skb_shared_hwtstamps *hwtstamps);
|
|
|
|
extern __sum16 __skb_checksum_complete_head(struct sk_buff *skb, int len);
|
|
extern __sum16 __skb_checksum_complete(struct sk_buff *skb);
|
|
|
|
static inline int skb_csum_unnecessary(const struct sk_buff *skb)
|
|
{
|
|
return skb->ip_summed & CHECKSUM_UNNECESSARY;
|
|
}
|
|
|
|
/**
|
|
* 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 __sum16 skb_checksum_complete(struct sk_buff *skb)
|
|
{
|
|
return skb_csum_unnecessary(skb) ?
|
|
0 : __skb_checksum_complete(skb);
|
|
}
|
|
|
|
#if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
|
|
extern void nf_conntrack_destroy(struct nf_conntrack *nfct);
|
|
static inline void nf_conntrack_put(struct nf_conntrack *nfct)
|
|
{
|
|
if (nfct && atomic_dec_and_test(&nfct->use))
|
|
nf_conntrack_destroy(nfct);
|
|
}
|
|
static inline void nf_conntrack_get(struct nf_conntrack *nfct)
|
|
{
|
|
if (nfct)
|
|
atomic_inc(&nfct->use);
|
|
}
|
|
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)
|
|
{
|
|
#if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
|
|
nf_conntrack_put(skb->nfct);
|
|
skb->nfct = NULL;
|
|
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
|
|
}
|
|
|
|
/* Note: This doesn't put any conntrack and bridge info in dst. */
|
|
static inline void __nf_copy(struct sk_buff *dst, const struct sk_buff *src)
|
|
{
|
|
#if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
|
|
dst->nfct = src->nfct;
|
|
nf_conntrack_get(src->nfct);
|
|
dst->nfctinfo = src->nfctinfo;
|
|
dst->nfct_reasm = src->nfct_reasm;
|
|
nf_conntrack_get_reasm(src->nfct_reasm);
|
|
#endif
|
|
#ifdef CONFIG_BRIDGE_NETFILTER
|
|
dst->nf_bridge = src->nf_bridge;
|
|
nf_bridge_get(src->nf_bridge);
|
|
#endif
|
|
}
|
|
|
|
static inline void nf_copy(struct sk_buff *dst, const struct sk_buff *src)
|
|
{
|
|
#if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
|
|
nf_conntrack_put(dst->nfct);
|
|
nf_conntrack_put_reasm(dst->nfct_reasm);
|
|
#endif
|
|
#ifdef CONFIG_BRIDGE_NETFILTER
|
|
nf_bridge_put(dst->nf_bridge);
|
|
#endif
|
|
__nf_copy(dst, src);
|
|
}
|
|
|
|
#ifdef CONFIG_NETWORK_SECMARK
|
|
static inline void skb_copy_secmark(struct sk_buff *to, const struct sk_buff *from)
|
|
{
|
|
to->secmark = from->secmark;
|
|
}
|
|
|
|
static inline void skb_init_secmark(struct sk_buff *skb)
|
|
{
|
|
skb->secmark = 0;
|
|
}
|
|
#else
|
|
static inline void skb_copy_secmark(struct sk_buff *to, const struct sk_buff *from)
|
|
{ }
|
|
|
|
static inline void skb_init_secmark(struct sk_buff *skb)
|
|
{ }
|
|
#endif
|
|
|
|
static inline void skb_set_queue_mapping(struct sk_buff *skb, u16 queue_mapping)
|
|
{
|
|
skb->queue_mapping = queue_mapping;
|
|
}
|
|
|
|
static inline u16 skb_get_queue_mapping(const struct sk_buff *skb)
|
|
{
|
|
return skb->queue_mapping;
|
|
}
|
|
|
|
static inline void skb_copy_queue_mapping(struct sk_buff *to, const struct sk_buff *from)
|
|
{
|
|
to->queue_mapping = from->queue_mapping;
|
|
}
|
|
|
|
static inline void skb_record_rx_queue(struct sk_buff *skb, u16 rx_queue)
|
|
{
|
|
skb->queue_mapping = rx_queue + 1;
|
|
}
|
|
|
|
static inline u16 skb_get_rx_queue(const struct sk_buff *skb)
|
|
{
|
|
return skb->queue_mapping - 1;
|
|
}
|
|
|
|
static inline bool skb_rx_queue_recorded(const struct sk_buff *skb)
|
|
{
|
|
return (skb->queue_mapping != 0);
|
|
}
|
|
|
|
extern u16 skb_tx_hash(const struct net_device *dev,
|
|
const struct sk_buff *skb);
|
|
|
|
#ifdef CONFIG_XFRM
|
|
static inline struct sec_path *skb_sec_path(struct sk_buff *skb)
|
|
{
|
|
return skb->sp;
|
|
}
|
|
#else
|
|
static inline struct sec_path *skb_sec_path(struct sk_buff *skb)
|
|
{
|
|
return NULL;
|
|
}
|
|
#endif
|
|
|
|
static inline int skb_is_gso(const struct sk_buff *skb)
|
|
{
|
|
return skb_shinfo(skb)->gso_size;
|
|
}
|
|
|
|
static inline int skb_is_gso_v6(const struct sk_buff *skb)
|
|
{
|
|
return skb_shinfo(skb)->gso_type & SKB_GSO_TCPV6;
|
|
}
|
|
|
|
extern void __skb_warn_lro_forwarding(const struct sk_buff *skb);
|
|
|
|
static inline bool skb_warn_if_lro(const struct sk_buff *skb)
|
|
{
|
|
/* LRO sets gso_size but not gso_type, whereas if GSO is really
|
|
* wanted then gso_type will be set. */
|
|
struct skb_shared_info *shinfo = skb_shinfo(skb);
|
|
if (shinfo->gso_size != 0 && unlikely(shinfo->gso_type == 0)) {
|
|
__skb_warn_lro_forwarding(skb);
|
|
return true;
|
|
}
|
|
return false;
|
|
}
|
|
|
|
static inline void skb_forward_csum(struct sk_buff *skb)
|
|
{
|
|
/* Unfortunately we don't support this one. Any brave souls? */
|
|
if (skb->ip_summed == CHECKSUM_COMPLETE)
|
|
skb->ip_summed = CHECKSUM_NONE;
|
|
}
|
|
|
|
bool skb_partial_csum_set(struct sk_buff *skb, u16 start, u16 off);
|
|
#endif /* __KERNEL__ */
|
|
#endif /* _LINUX_SKBUFF_H */
|