--- /dev/null
+/*
+ * Definitions for the 'struct sk_buff' memory handlers.
+ *
+ * Authors:
+ * Alan Cox, <gw4pts@gw4pts.ampr.org>
+ * Florian La Roche, <rzsfl@rz.uni-sb.de>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#ifndef _LINUX_SKBUFF_H
+#define _LINUX_SKBUFF_H
+
+#include <linux/config.h>
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/time.h>
+#include <linux/cache.h>
+
+#include <asm/atomic.h>
+#include <asm/types.h>
+#include <linux/spinlock.h>
+#include <linux/mm.h>
+#include <linux/highmem.h>
+
+#define HAVE_ALLOC_SKB /* For the drivers to know */
+#define HAVE_ALIGNABLE_SKB /* Ditto 8) */
+#define SLAB_SKB /* Slabified skbuffs */
+
+#define CHECKSUM_NONE 0
+#define CHECKSUM_HW 1
+#define CHECKSUM_UNNECESSARY 2
+
+#define SKB_DATA_ALIGN(X) (((X) + (SMP_CACHE_BYTES-1)) & ~(SMP_CACHE_BYTES-1))
+#define SKB_MAX_ORDER(X,ORDER) (((PAGE_SIZE<<(ORDER)) - (X) - sizeof(struct skb_shared_info))&~(SMP_CACHE_BYTES-1))
+#define SKB_MAX_HEAD(X) (SKB_MAX_ORDER((X),0))
+#define SKB_MAX_ALLOC (SKB_MAX_ORDER(0,2))
+
+/* A. Checksumming of received packets by device.
+ *
+ * NONE: device failed to checksum this packet.
+ * skb->csum is undefined.
+ *
+ * UNNECESSARY: device parsed packet and wouldbe verified checksum.
+ * skb->csum is undefined.
+ * It is bad option, but, unfortunately, many of vendors do this.
+ * Apparently with secret goal to sell you new device, when you
+ * will add new protocol to your host. F.e. IPv6. 8)
+ *
+ * HW: the most generic way. Device supplied checksum of _all_
+ * the packet as seen by netif_rx in skb->csum.
+ * NOTE: Even if device supports only some protocols, but
+ * is able to produce some skb->csum, it MUST use HW,
+ * not UNNECESSARY.
+ *
+ * B. Checksumming on output.
+ *
+ * NONE: skb is checksummed by protocol or csum is not required.
+ *
+ * HW: device is required to csum packet as seen by hard_start_xmit
+ * from skb->h.raw to the end and to record the checksum
+ * at skb->h.raw+skb->csum.
+ *
+ * Device must show its capabilities in dev->features, set
+ * at device setup time.
+ * NETIF_F_HW_CSUM - it is clever device, it is able to checksum
+ * everything.
+ * NETIF_F_NO_CSUM - loopback or reliable single hop media.
+ * NETIF_F_IP_CSUM - device is dumb. It is able to csum only
+ * TCP/UDP over IPv4. Sigh. Vendors like this
+ * way by an unknown reason. Though, see comment above
+ * about CHECKSUM_UNNECESSARY. 8)
+ *
+ * Any questions? No questions, good. --ANK
+ */
+
+#ifdef __i386__
+#define NET_CALLER(arg) (*(((void**)&arg)-1))
+#else
+#define NET_CALLER(arg) __builtin_return_address(0)
+#endif
+
+#ifdef CONFIG_NETFILTER
+struct nf_conntrack {
+ atomic_t use;
+ void (*destroy)(struct nf_conntrack *);
+};
+
+struct nf_ct_info {
+ struct nf_conntrack *master;
+};
+#endif
+
+struct sk_buff_head {
+ /* These two members must be first. */
+ struct sk_buff * next;
+ struct sk_buff * prev;
+
+ __u32 qlen;
+ spinlock_t lock;
+};
+
+struct sk_buff;
+
+#define MAX_SKB_FRAGS 6
+
+typedef struct skb_frag_struct skb_frag_t;
+
+struct skb_frag_struct
+{
+ struct page *page;
+ __u16 page_offset;
+ __u16 size;
+};
+
+/* This data is invariant across clones and lives at
+ * the end of the header data, ie. at skb->end.
+ */
+struct skb_shared_info {
+ atomic_t dataref;
+ unsigned int nr_frags;
+ struct sk_buff *frag_list;
+ skb_frag_t frags[MAX_SKB_FRAGS];
+};
+
+struct sk_buff {
+ /* These two members must be first. */
+ struct sk_buff * next; /* Next buffer in list */
+ struct sk_buff * prev; /* Previous buffer in list */
+
+ struct sk_buff_head * list; /* List we are on */
+ struct sock *sk; /* Socket we are owned by */
+ struct timeval stamp; /* Time we arrived */
+ struct net_device *dev; /* Device we arrived on/are leaving by */
+ struct net_device *real_dev; /* For support of point to point protocols
+ (e.g. 802.3ad) over bonding, we must save the
+ physical device that got the packet before
+ replacing skb->dev with the virtual device. */
+
+ /* Transport layer header */
+ union
+ {
+ struct tcphdr *th;
+ struct udphdr *uh;
+ struct icmphdr *icmph;
+ struct igmphdr *igmph;
+ struct iphdr *ipiph;
+ struct spxhdr *spxh;
+ unsigned char *raw;
+ } h;
+
+ /* Network layer header */
+ union
+ {
+ struct iphdr *iph;
+ struct ipv6hdr *ipv6h;
+ struct arphdr *arph;
+ struct ipxhdr *ipxh;
+ unsigned char *raw;
+ } nh;
+
+ /* Link layer header */
+ union
+ {
+ struct ethhdr *ethernet;
+ unsigned char *raw;
+ } mac;
+
+ struct dst_entry *dst;
+
+ /*
+ * This is the control buffer. It is free to use for every
+ * layer. Please put your private variables there. If you
+ * want to keep them across layers you have to do a skb_clone()
+ * first. This is owned by whoever has the skb queued ATM.
+ */
+ char cb[48];
+
+ unsigned int len; /* Length of actual data */
+ unsigned int data_len;
+ unsigned int csum; /* Checksum */
+ unsigned char __unused, /* Dead field, may be reused */
+ cloned, /* head may be cloned (check refcnt to be sure). */
+ pkt_type, /* Packet class */
+ ip_summed; /* Driver fed us an IP checksum */
+ __u32 priority; /* Packet queueing priority */
+ atomic_t users; /* User count - see datagram.c,tcp.c */
+ unsigned short protocol; /* Packet protocol from driver. */
+ unsigned short security; /* Security level of packet */
+ unsigned int truesize; /* Buffer size */
+
+ unsigned char *head; /* Head of buffer */
+ unsigned char *data; /* Data head pointer */
+ unsigned char *tail; /* Tail pointer */
+ unsigned char *end; /* End pointer */
+
+ void (*destructor)(struct sk_buff *); /* Destruct function */
+#ifdef CONFIG_NETFILTER
+ /* Can be used for communication between hooks. */
+ unsigned long nfmark;
+ /* Cache info */
+ __u32 nfcache;
+ /* Associated connection, if any */
+ struct nf_ct_info *nfct;
+#ifdef CONFIG_NETFILTER_DEBUG
+ unsigned int nf_debug;
+#endif
+#endif /*CONFIG_NETFILTER*/
+
+#if defined(CONFIG_HIPPI)
+ union{
+ __u32 ifield;
+ } private;
+#endif
+
+#ifdef CONFIG_NET_SCHED
+ __u32 tc_index; /* traffic control index */
+#endif
+};
+
+#ifdef __KERNEL__
+/*
+ * Handling routines are only of interest to the kernel
+ */
+#include <linux/slab.h>
+
+#include <asm/system.h>
+
+extern void __kfree_skb(struct sk_buff *skb);
+extern struct sk_buff * alloc_skb(unsigned int size, int priority);
+extern void kfree_skbmem(struct sk_buff *skb);
+extern struct sk_buff * skb_clone(struct sk_buff *skb, int priority);
+extern struct sk_buff * skb_copy(const struct sk_buff *skb, int priority);
+extern struct sk_buff * pskb_copy(struct sk_buff *skb, int gfp_mask);
+extern int pskb_expand_head(struct sk_buff *skb, int nhead, int ntail, int gfp_mask);
+extern struct sk_buff * skb_realloc_headroom(struct sk_buff *skb, unsigned int headroom);
+extern struct sk_buff * skb_copy_expand(const struct sk_buff *skb,
+ int newheadroom,
+ int newtailroom,
+ int priority);
+extern struct sk_buff * skb_pad(struct sk_buff *skb, int pad);
+#define dev_kfree_skb(a) kfree_skb(a)
+extern void skb_over_panic(struct sk_buff *skb, int len, void *here);
+extern void skb_under_panic(struct sk_buff *skb, int len, void *here);
+
+/* Internal */
+#define skb_shinfo(SKB) ((struct skb_shared_info *)((SKB)->end))
+
+/**
+ * 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(struct sk_buff_head *list)
+{
+ return (list->next == (struct sk_buff *) list);
+}
+
+/**
+ * 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.
+ */
+
+/**
+ * kfree_skb - free an sk_buff
+ * @skb: buffer to free
+ *
+ * Drop a reference to the buffer and free it if the usage count has
+ * hit zero.
+ */
+
+static inline void kfree_skb(struct sk_buff *skb)
+{
+ if (atomic_read(&skb->users) == 1 || atomic_dec_and_test(&skb->users))
+ __kfree_skb(skb);
+}
+
+/* Use this if you didn't touch the skb state [for fast switching] */
+static inline void kfree_skb_fast(struct sk_buff *skb)
+{
+ if (atomic_read(&skb->users) == 1 || atomic_dec_and_test(&skb->users))
+ kfree_skbmem(skb);
+}
+
+/**
+ * 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(struct sk_buff *skb)
+{
+ return skb->cloned && atomic_read(&skb_shinfo(skb)->dataref) != 1;
+}
+
+/**
+ * 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(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, int pri)
+{
+ if (skb_shared(skb)) {
+ struct sk_buff *nskb;
+ nskb = skb_clone(skb, pri);
+ kfree_skb(skb);
+ return 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, int pri)
+{
+ struct sk_buff *nskb;
+ if(!skb_cloned(skb))
+ return skb;
+ nskb=skb_copy(skb, pri);
+ kfree_skb(skb); /* Free our shared copy */
+ return nskb;
+}
+
+/**
+ * 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(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 = (struct sk_buff *)list;
+ 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_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.
+ */
+
+static inline void __skb_queue_head(struct sk_buff_head *list, struct sk_buff *newsk)
+{
+ struct sk_buff *prev, *next;
+
+ newsk->list = list;
+ list->qlen++;
+ prev = (struct sk_buff *)list;
+ next = prev->next;
+ newsk->next = next;
+ newsk->prev = prev;
+ next->prev = newsk;
+ 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 the list. This function takes the
+ * list lock and can be used safely with other locking &sk_buff functions
+ * safely.
+ *
+ * A buffer cannot be placed on two lists at the same time.
+ */
+
+static inline void skb_queue_head(struct sk_buff_head *list, struct sk_buff *newsk)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&list->lock, flags);
+ __skb_queue_head(list, newsk);
+ spin_unlock_irqrestore(&list->lock, flags);
+}
+
+/**
+ * __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.
+ */
+
+
+static inline void __skb_queue_tail(struct sk_buff_head *list, struct sk_buff *newsk)
+{
+ struct sk_buff *prev, *next;
+
+ newsk->list = list;
+ list->qlen++;
+ next = (struct sk_buff *)list;
+ prev = next->prev;
+ newsk->next = next;
+ newsk->prev = prev;
+ next->prev = newsk;
+ prev->next = newsk;
+}
+
+/**
+ * skb_queue_tail - queue a buffer at the list tail
+ * @list: list to use
+ * @newsk: buffer to queue
+ *
+ * Queue a buffer at the tail of the list. This function takes the
+ * list lock and can be used safely with other locking &sk_buff functions
+ * safely.
+ *
+ * A buffer cannot be placed on two lists at the same time.
+ */
+
+static inline void skb_queue_tail(struct sk_buff_head *list, struct sk_buff *newsk)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&list->lock, flags);
+ __skb_queue_tail(list, newsk);
+ spin_unlock_irqrestore(&list->lock, flags);
+}
+
+/**
+ * __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.
+ */
+
+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 = NULL;
+ result->prev = NULL;
+ result->list = NULL;
+ }
+ return result;
+}
+
+/**
+ * skb_dequeue - remove from the head of the queue
+ * @list: list to dequeue from
+ *
+ * Remove the head of the list. The list lock is taken so the function
+ * may be used safely with other locking list functions. The head item is
+ * returned or %NULL if the list is empty.
+ */
+
+static inline struct sk_buff *skb_dequeue(struct sk_buff_head *list)
+{
+ unsigned long flags;
+ struct sk_buff *result;
+
+ spin_lock_irqsave(&list->lock, flags);
+ result = __skb_dequeue(list);
+ spin_unlock_irqrestore(&list->lock, flags);
+ return result;
+}
+
+/*
+ * Insert a packet on a 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 = newsk;
+ prev->next = newsk;
+ newsk->list = list;
+ list->qlen++;
+}
+
+/**
+ * skb_insert - insert a buffer
+ * @old: buffer to insert before
+ * @newsk: buffer to insert
+ *
+ * Place a packet before a given packet in a list. The list locks are taken
+ * and this function is atomic with respect to other list locked calls
+ * A buffer cannot be placed on two lists at the same time.
+ */
+
+static inline void skb_insert(struct sk_buff *old, struct sk_buff *newsk)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&old->list->lock, flags);
+ __skb_insert(newsk, old->prev, old, old->list);
+ spin_unlock_irqrestore(&old->list->lock, flags);
+}
+
+/*
+ * Place a packet after a given packet in a list.
+ */
+
+static inline void __skb_append(struct sk_buff *old, struct sk_buff *newsk)
+{
+ __skb_insert(newsk, old, old->next, old->list);
+}
+
+/**
+ * skb_append - append a buffer
+ * @old: buffer to insert after
+ * @newsk: buffer to insert
+ *
+ * Place a packet after a given packet in a list. The list locks are taken
+ * and this function is atomic with respect to other list locked calls.
+ * A buffer cannot be placed on two lists at the same time.
+ */
+
+
+static inline void skb_append(struct sk_buff *old, struct sk_buff *newsk)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&old->list->lock, flags);
+ __skb_append(old, newsk);
+ spin_unlock_irqrestore(&old->list->lock, flags);
+}
+
+/*
+ * remove sk_buff from list. _Must_ be called atomically, and with
+ * the list known..
+ */
+
+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 = NULL;
+ skb->prev = NULL;
+ skb->list = NULL;
+ next->prev = prev;
+ prev->next = next;
+}
+
+/**
+ * skb_unlink - remove a buffer from a list
+ * @skb: buffer to remove
+ *
+ * Place a packet after a given packet in a list. The list locks are taken
+ * and this function is atomic with respect to other list locked calls
+ *
+ * Works even without knowing the list it is sitting on, which can be
+ * handy at times. It also means that THE LIST MUST EXIST when you
+ * unlink. Thus a list must have its contents unlinked before it is
+ * destroyed.
+ */
+
+static inline void skb_unlink(struct sk_buff *skb)
+{
+ struct sk_buff_head *list = skb->list;
+
+ if(list) {
+ unsigned long flags;
+
+ spin_lock_irqsave(&list->lock, flags);
+ if(skb->list == list)
+ __skb_unlink(skb, skb->list);
+ spin_unlock_irqrestore(&list->lock, flags);
+ }
+}
+
+/* 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.
+ */
+
+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;
+}
+
+/**
+ * skb_dequeue - remove from the head of the queue
+ * @list: list to dequeue from
+ *
+ * Remove the head of the list. The list lock is taken so the function
+ * may be used safely with other locking list functions. The tail item is
+ * returned or %NULL if the list is empty.
+ */
+
+static inline struct sk_buff *skb_dequeue_tail(struct sk_buff_head *list)
+{
+ unsigned long flags;
+ struct sk_buff *result;
+
+ spin_lock_irqsave(&list->lock, flags);
+ result = __skb_dequeue_tail(list);
+ spin_unlock_irqrestore(&list->lock, flags);
+ return result;
+}
+
+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;
+}
+
+#define SKB_PAGE_ASSERT(skb) do { if (skb_shinfo(skb)->nr_frags) out_of_line_bug(); } while (0)
+#define SKB_FRAG_ASSERT(skb) do { if (skb_shinfo(skb)->frag_list) out_of_line_bug(); } while (0)
+#define SKB_LINEAR_ASSERT(skb) do { if (skb_is_nonlinear(skb)) out_of_line_bug(); } while (0)
+
+/*
+ * 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(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(skb->data<skb->head) {
+ skb_under_panic(skb, len, current_text_addr());
+ }
+ return skb->data;
+}
+
+static inline char *__skb_pull(struct sk_buff *skb, unsigned int len)
+{
+ skb->len-=len;
+ if (skb->len < skb->data_len)
+ out_of_line_bug();
+ 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)
+{
+ if (len > skb->len)
+ return NULL;
+ return __skb_pull(skb,len);
+}
+
+extern unsigned char * __pskb_pull_tail(struct sk_buff *skb, int delta);
+
+static inline char *__pskb_pull(struct sk_buff *skb, unsigned int len)
+{
+ if (len > skb_headlen(skb) &&
+ __pskb_pull_tail(skb, len-skb_headlen(skb)) == NULL)
+ return NULL;
+ skb->len -= len;
+ return skb->data += len;
+}
+
+static inline unsigned char * pskb_pull(struct sk_buff *skb, unsigned int len)
+{
+ if (len > skb->len)
+ return NULL;
+ return __pskb_pull(skb,len);
+}
+
+static inline int pskb_may_pull(struct sk_buff *skb, unsigned int len)
+{
+ if (len <= skb_headlen(skb))
+ return 1;
+ if (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, unsigned int len)
+{
+ skb->data+=len;
+ skb->tail+=len;
+}
+
+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;
+ } else {
+ return ___pskb_trim(skb, len, 1);
+ }
+}
+
+static inline int pskb_trim(struct sk_buff *skb, unsigned int len)
+{
+ if (len < skb->len)
+ return __pskb_trim(skb, len);
+ return 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_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 takes the list
+ * lock and is atomic with respect to other list locking functions.
+ */
+
+
+static inline void skb_queue_purge(struct sk_buff_head *list)
+{
+ struct sk_buff *skb;
+ while ((skb=skb_dequeue(list))!=NULL)
+ kfree_skb(skb);
+}
+
+/**
+ * __skb_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.
+ */
+
+
+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 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,
+ int gfp_mask)
+{
+ struct sk_buff *skb;
+#if defined(CONFIG_XEN)
+ length = (PAGE_SIZE/2)+1; /* force slab allocater to give us a page */
+#endif
+ skb = alloc_skb(length+16, gfp_mask);
+ if (skb)
+ skb_reserve(skb,16);
+ return skb;
+}
+
+/**
+ * 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);
+}
+
+/**
+ * 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. */
+int skb_linearize(struct sk_buff *skb, int gfp);
+
+static inline void *kmap_skb_frag(const skb_frag_t *frag)
+{
+#ifdef CONFIG_HIGHMEM
+ if (in_irq())
+ out_of_line_bug();
+
+ 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; \
+ (skb != (struct sk_buff *)(queue)); \
+ skb=skb->next)
+
+
+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(const struct sk_buff *from, int offset, char *to,int size);
+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(const struct sk_buff *skb, int offset, u8 *to, int len, unsigned int *csump);
+extern int skb_copy_and_csum_datagram_iovec(const struct sk_buff *skb, int hlen, struct iovec *iov);
+extern void skb_free_datagram(struct sock * sk, struct sk_buff *skb);
+
+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 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_init(void);
+extern void skb_add_mtu(int mtu);
+
+#ifdef CONFIG_NETFILTER
+static inline void
+nf_conntrack_put(struct nf_ct_info *nfct)
+{
+ if (nfct && atomic_dec_and_test(&nfct->master->use))
+ nfct->master->destroy(nfct->master);
+}
+static inline void
+nf_conntrack_get(struct nf_ct_info *nfct)
+{
+ if (nfct)
+ atomic_inc(&nfct->master->use);
+}
+#endif
+
+#endif /* __KERNEL__ */
+#endif /* _LINUX_SKBUFF_H */
projects / xen.git / commitdiff