--- /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>
+
+/* Zero Copy additions:
+ *
+ * (1) there are now two types of skb, as indicated by the skb_type field.
+ * this is because, at least for the time being, there are two seperate types
+ * of memory that may be allocated to skb->data.
+ *
+ * (2) until discontiguous memory is fully supported, there will be a free list of pages
+ * to be used by the net RX code. This list will be allocated in the driver init code
+ * but is declared here because the socket free code needs to return pages to it.
+ */
+
+// for skb->skb_type:
+
+#define SKB_NORMAL 0
+#define SKB_ZERO_COPY 1
+
+#define NUM_NET_PAGES 9 // about 1Meg of buffers. (2^9)
+struct net_page_info {
+ struct list_head list;
+ unsigned long virt_addr;
+ unsigned long ppte;
+};
+
+extern char *net_page_chunk;
+extern struct net_page_info *net_page_table;
+extern struct list_head net_page_list;
+extern spinlock_t net_page_list_lock;
+extern unsigned int net_pages;
+
+/* End zero copy additions */
+
+#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 */
+
+ /* 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
+ unsigned int skb_type; /* for zero copy handling. */
+ struct net_page_info *net_page;
+};
+
+#define SK_WMEM_MAX 65535
+#define SK_RMEM_MAX 65535
+
+#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 struct sk_buff * alloc_zc_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);
+#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)
+{
+ 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)
+{
+ 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 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) BUG(); } while (0)
+#define SKB_FRAG_ASSERT(skb) do { if (skb_shinfo(skb)->frag_list) BUG(); } while (0)
+#define SKB_LINEAR_ASSERT(skb) do { if (skb_is_nonlinear(skb)) 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)
+ 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;
+
+ //skb = alloc_skb(length+16, gfp_mask);
+ skb = alloc_zc_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_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())
+ 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 */
--- /dev/null
+/*
+ * Routines having to do with the 'struct sk_buff' memory handlers.
+ *
+ * Authors: Alan Cox <iiitac@pyr.swan.ac.uk>
+ * Florian La Roche <rzsfl@rz.uni-sb.de>
+ *
+ * Version: $Id: skbuff.c,v 1.89 2001/08/06 13:25:02 davem Exp $
+ *
+ * Fixes:
+ * Alan Cox : Fixed the worst of the load balancer bugs.
+ * Dave Platt : Interrupt stacking fix.
+ * Richard Kooijman : Timestamp fixes.
+ * Alan Cox : Changed buffer format.
+ * Alan Cox : destructor hook for AF_UNIX etc.
+ * Linus Torvalds : Better skb_clone.
+ * Alan Cox : Added skb_copy.
+ * Alan Cox : Added all the changed routines Linus
+ * only put in the headers
+ * Ray VanTassle : Fixed --skb->lock in free
+ * Alan Cox : skb_copy copy arp field
+ * Andi Kleen : slabified it.
+ *
+ * NOTE:
+ * The __skb_ routines should be called with interrupts
+ * disabled, or you better be *real* sure that the operation is atomic
+ * with respect to whatever list is being frobbed (e.g. via lock_sock()
+ * or via disabling bottom half handlers, etc).
+ *
+ * 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.
+ */
+
+/*
+ * The functions in this file will not compile correctly with gcc 2.4.x
+ */
+
+#include <linux/config.h>
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/mm.h>
+#include <linux/interrupt.h>
+#include <linux/in.h>
+#include <linux/inet.h>
+#include <linux/slab.h>
+#include <linux/netdevice.h>
+#include <linux/string.h>
+#include <linux/skbuff.h>
+#include <linux/cache.h>
+#include <linux/init.h>
+#include <linux/highmem.h>
+#include <linux/spinlock.h>
+
+#include <net/ip.h>
+#include <net/protocol.h>
+#include <net/dst.h>
+#include <net/tcp.h>
+#include <net/udp.h>
+#include <net/sock.h>
+
+#include <asm/uaccess.h>
+#include <asm/system.h>
+
+/* zc globals: */
+char *net_page_chunk;
+struct net_page_info *net_page_table;
+struct list_head net_page_list;
+spinlock_t net_page_list_lock = SPIN_LOCK_UNLOCKED;
+unsigned int net_pages;
+
+
+
+int sysctl_hot_list_len = 128;
+
+static kmem_cache_t *skbuff_head_cache;
+
+static union {
+ struct sk_buff_head list;
+ char pad[SMP_CACHE_BYTES];
+} skb_head_pool[NR_CPUS];
+
+/*
+ * Keep out-of-line to prevent kernel bloat.
+ * __builtin_return_address is not used because it is not always
+ * reliable.
+ */
+
+/**
+ * skb_over_panic - private function
+ * @skb: buffer
+ * @sz: size
+ * @here: address
+ *
+ * Out of line support code for skb_put(). Not user callable.
+ */
+
+void skb_over_panic(struct sk_buff *skb, int sz, void *here)
+{
+ printk("skput:over: %p:%d put:%d dev:%s",
+ here, skb->len, sz, skb->dev ? skb->dev->name : "<NULL>");
+ BUG();
+}
+
+/**
+ * skb_under_panic - private function
+ * @skb: buffer
+ * @sz: size
+ * @here: address
+ *
+ * Out of line support code for skb_push(). Not user callable.
+ */
+
+
+void skb_under_panic(struct sk_buff *skb, int sz, void *here)
+{
+ printk("skput:under: %p:%d put:%d dev:%s",
+ here, skb->len, sz, skb->dev ? skb->dev->name : "<NULL>");
+ BUG();
+}
+
+static __inline__ struct sk_buff *skb_head_from_pool(void)
+{
+ struct sk_buff_head *list = &skb_head_pool[smp_processor_id()].list;
+
+ if (skb_queue_len(list)) {
+ struct sk_buff *skb;
+ unsigned long flags;
+
+ local_irq_save(flags);
+ skb = __skb_dequeue(list);
+ local_irq_restore(flags);
+ return skb;
+ }
+ return NULL;
+}
+
+static __inline__ void skb_head_to_pool(struct sk_buff *skb)
+{
+ struct sk_buff_head *list = &skb_head_pool[smp_processor_id()].list;
+
+ if (skb_queue_len(list) < sysctl_hot_list_len) {
+ unsigned long flags;
+
+ local_irq_save(flags);
+ __skb_queue_head(list, skb);
+ local_irq_restore(flags);
+
+ return;
+ }
+ kmem_cache_free(skbuff_head_cache, skb);
+}
+
+
+/* Allocate a new skbuff. We do this ourselves so we can fill in a few
+ * 'private' fields and also do memory statistics to find all the
+ * [BEEP] leaks.
+ *
+ */
+
+/**
+ * alloc_skb - allocate a network buffer
+ * @size: size to allocate
+ * @gfp_mask: allocation mask
+ *
+ * Allocate a new &sk_buff. The returned buffer has no headroom and a
+ * tail room of size bytes. The object has a reference count of one.
+ * The return is the buffer. On a failure the return is %NULL.
+ *
+ * Buffers may only be allocated from interrupts using a @gfp_mask of
+ * %GFP_ATOMIC.
+ */
+
+struct sk_buff *alloc_skb(unsigned int size,int gfp_mask)
+{
+ struct sk_buff *skb;
+ u8 *data;
+
+ if (in_interrupt() && (gfp_mask & __GFP_WAIT)) {
+ static int count = 0;
+ if (++count < 5) {
+ printk(KERN_ERR "alloc_skb called nonatomically "
+ "from interrupt %p\n", NET_CALLER(size));
+ BUG();
+ }
+ gfp_mask &= ~__GFP_WAIT;
+ }
+
+ /* Get the HEAD */
+ skb = skb_head_from_pool();
+ if (skb == NULL) {
+ skb = kmem_cache_alloc(skbuff_head_cache, gfp_mask & ~__GFP_DMA);
+ if (skb == NULL)
+ goto nohead;
+ }
+
+ /* Get the DATA. Size must match skb_add_mtu(). */
+ size = SKB_DATA_ALIGN(size);
+ data = kmalloc(size + sizeof(struct skb_shared_info), gfp_mask);
+ if (data == NULL)
+ goto nodata;
+
+ /* XXX: does not include slab overhead */
+ skb->truesize = size + sizeof(struct sk_buff);
+
+ /* Load the data pointers. */
+ skb->head = data;
+ skb->data = data;
+ skb->tail = data;
+ skb->end = data + size;
+
+ /* Set up other state */
+ skb->len = 0;
+ skb->cloned = 0;
+ skb->data_len = 0;
+ skb->skb_type = SKB_NORMAL;
+
+ atomic_set(&skb->users, 1);
+ atomic_set(&(skb_shinfo(skb)->dataref), 1);
+ skb_shinfo(skb)->nr_frags = 0;
+ skb_shinfo(skb)->frag_list = NULL;
+ return skb;
+
+nodata:
+ skb_head_to_pool(skb);
+nohead:
+ return NULL;
+}
+
+/* begin zc code additions: */
+
+void init_net_pages(unsigned long order_pages)
+{
+ int i;
+ struct net_page_info *np;
+ pgd_t *pgd; pmd_t *pmd; pte_t *ptep;
+ unsigned long nr_pages = 1 << order_pages;
+
+ net_page_chunk = (char *)__get_free_pages(GFP_KERNEL, order_pages);
+ net_page_table = kmalloc(nr_pages * sizeof(struct net_page_info), GFP_KERNEL);
+
+ INIT_LIST_HEAD(&net_page_list);
+
+ for (i = 0; i < nr_pages; i++)
+ {
+ np = net_page_table + i;
+ np->virt_addr = (unsigned long)net_page_chunk + (i * PAGE_SIZE);
+
+ // now fill the pte pointer:
+ np->ppte = 0xdeadbeef;
+ pgd = pgd_offset_k(np->virt_addr);
+ if (!pgd_none(*pgd))
+ {
+ pmd = pmd_offset(pgd, np->virt_addr);
+ if (!pmd_none(*pmd))
+ {
+ ptep = pte_offset(pmd, np->virt_addr);
+ np->ppte = (unsigned long)ptep; // neet to virt_to_phys this?
+ }
+ }
+
+ list_add_tail(&np->list, &net_page_list);
+ }
+ net_pages = nr_pages;
+
+
+}
+
+struct net_page_info *get_net_page(void)
+{
+ struct list_head *list_ptr;
+ struct net_page_info *np;
+ unsigned long flags;
+
+ if (!net_pages)
+ {
+ return NULL;
+ }
+ spin_lock_irqsave(&net_page_list_lock, flags);
+
+ list_ptr = net_page_list.next;
+ np = list_entry(list_ptr, struct net_page_info, list);
+ list_del(&np->list);
+ net_pages--;
+
+ spin_unlock_irqrestore(&net_page_list_lock, flags);
+
+ return np;
+}
+
+void free_net_page(struct net_page_info *np)
+{
+ unsigned long flags;
+
+ if (np == NULL) return;
+
+ spin_lock_irqsave(&net_page_list_lock, flags);
+
+ list_add_tail(&np->list, &net_page_list);
+ net_pages++;
+
+ spin_unlock_irqrestore(&net_page_list_lock, flags);
+}
+
+struct sk_buff *alloc_zc_skb(unsigned int size,int gfp_mask)
+{
+ struct sk_buff *skb;
+ u8 *data;
+
+ if (in_interrupt() && (gfp_mask & __GFP_WAIT)) {
+ static int count = 0;
+ if (++count < 5) {
+ printk(KERN_ERR "alloc_skb called nonatomically "
+ "from interrupt %p\n", NET_CALLER(size));
+ BUG();
+ }
+ gfp_mask &= ~__GFP_WAIT;
+ }
+
+ /* Get the HEAD */
+ skb = skb_head_from_pool();
+ if (skb == NULL) {
+ skb = kmem_cache_alloc(skbuff_head_cache, gfp_mask & ~__GFP_DMA);
+ if (skb == NULL)
+ goto nohead;
+ }
+
+ /* Get the DATA. Size must match skb_add_mtu(). */
+ size = SKB_DATA_ALIGN(size);
+ if (size > PAGE_SIZE)
+ {
+ printk("alloc_zc_skb called with unruly size.\n");
+ size = PAGE_SIZE;
+ }
+ skb->net_page = get_net_page();
+ if (skb->net_page == NULL)
+ {
+ goto nodata;
+ }
+ data = (u8 *)skb->net_page->virt_addr;
+ if (data == NULL)
+ goto nodata;
+ /* XXX: does not include slab overhead */
+ skb->truesize = size + sizeof(struct sk_buff);
+
+ /* Load the data pointers. */
+ skb->head = data;
+ skb->data = data;
+ skb->tail = data;
+ skb->end = data + size;
+
+ /* Set up other state */
+ skb->len = 0;
+ skb->cloned = 0;
+ skb->data_len = 0;
+ skb->skb_type = SKB_ZERO_COPY;
+
+ atomic_set(&skb->users, 1);
+ atomic_set(&(skb_shinfo(skb)->dataref), 1);
+ skb_shinfo(skb)->nr_frags = 0;
+ skb_shinfo(skb)->frag_list = NULL;
+ return skb;
+
+nodata:
+ skb_head_to_pool(skb);
+nohead:
+ return NULL;
+}
+
+/* end zc code additions: */
+
+/*
+ * Slab constructor for a skb head.
+ */
+static inline void skb_headerinit(void *p, kmem_cache_t *cache,
+ unsigned long flags)
+{
+ struct sk_buff *skb = p;
+
+ skb->next = NULL;
+ skb->prev = NULL;
+ skb->list = NULL;
+ skb->sk = NULL;
+ skb->stamp.tv_sec=0; /* No idea about time */
+ skb->dev = NULL;
+ skb->dst = NULL;
+ memset(skb->cb, 0, sizeof(skb->cb));
+ skb->pkt_type = PACKET_HOST; /* Default type */
+ skb->ip_summed = 0;
+ skb->priority = 0;
+ skb->security = 0; /* By default packets are insecure */
+ skb->destructor = NULL;
+
+#ifdef CONFIG_NETFILTER
+ skb->nfmark = skb->nfcache = 0;
+ skb->nfct = NULL;
+#ifdef CONFIG_NETFILTER_DEBUG
+ skb->nf_debug = 0;
+#endif
+#endif
+#ifdef CONFIG_NET_SCHED
+ skb->tc_index = 0;
+#endif
+}
+
+static void skb_drop_fraglist(struct sk_buff *skb)
+{
+ struct sk_buff *list = skb_shinfo(skb)->frag_list;
+
+ skb_shinfo(skb)->frag_list = NULL;
+
+ do {
+ struct sk_buff *this = list;
+ list = list->next;
+ kfree_skb(this);
+ } while (list);
+}
+
+static void skb_clone_fraglist(struct sk_buff *skb)
+{
+ struct sk_buff *list;
+
+ for (list = skb_shinfo(skb)->frag_list; list; list=list->next)
+ skb_get(list);
+}
+
+static void skb_release_data(struct sk_buff *skb)
+{
+ if (!skb->cloned ||
+ atomic_dec_and_test(&(skb_shinfo(skb)->dataref))) {
+ if (skb_shinfo(skb)->nr_frags) {
+ int i;
+ for (i = 0; i < skb_shinfo(skb)->nr_frags; i++)
+ put_page(skb_shinfo(skb)->frags[i].page);
+ }
+
+ if (skb_shinfo(skb)->frag_list)
+ skb_drop_fraglist(skb);
+
+ if (skb->skb_type == SKB_NORMAL)
+ {
+ kfree(skb->head);
+ } else {// SKB_ZERO_COPY
+ free_net_page(skb->net_page);
+ }
+ }
+}
+
+/*
+ * Free an skbuff by memory without cleaning the state.
+ */
+void kfree_skbmem(struct sk_buff *skb)
+{
+ skb_release_data(skb);
+ skb_head_to_pool(skb);
+}
+
+/**
+ * __kfree_skb - private function
+ * @skb: buffer
+ *
+ * Free an sk_buff. Release anything attached to the buffer.
+ * Clean the state. This is an internal helper function. Users should
+ * always call kfree_skb
+ */
+
+void __kfree_skb(struct sk_buff *skb)
+{
+ if (skb->list) {
+ printk(KERN_WARNING "Warning: kfree_skb passed an skb still "
+ "on a list (from %p).\n", NET_CALLER(skb));
+ BUG();
+ }
+
+ dst_release(skb->dst);
+ if(skb->destructor) {
+ if (in_irq()) {
+ printk(KERN_WARNING "Warning: kfree_skb on hard IRQ %p\n",
+ NET_CALLER(skb));
+ }
+ skb->destructor(skb);
+ }
+#ifdef CONFIG_NETFILTER
+ nf_conntrack_put(skb->nfct);
+#endif
+ skb_headerinit(skb, NULL, 0); /* clean state */
+ kfree_skbmem(skb);
+}
+
+/**
+ * skb_clone - duplicate an sk_buff
+ * @skb: buffer to clone
+ * @gfp_mask: allocation priority
+ *
+ * Duplicate an &sk_buff. The new one is not owned by a socket. Both
+ * copies share the same packet data but not structure. The new
+ * buffer has a reference count of 1. If the allocation fails the
+ * function returns %NULL otherwise the new buffer is returned.
+ *
+ * If this function is called from an interrupt gfp_mask() must be
+ * %GFP_ATOMIC.
+ */
+
+struct sk_buff *skb_clone(struct sk_buff *skb, int gfp_mask)
+{
+ struct sk_buff *n;
+
+ n = skb_head_from_pool();
+ if (!n) {
+ n = kmem_cache_alloc(skbuff_head_cache, gfp_mask);
+ if (!n)
+ return NULL;
+ }
+
+#define C(x) n->x = skb->x
+
+ n->next = n->prev = NULL;
+ n->list = NULL;
+ n->sk = NULL;
+ C(stamp);
+ C(dev);
+ C(h);
+ C(nh);
+ C(mac);
+ C(dst);
+ dst_clone(n->dst);
+ memcpy(n->cb, skb->cb, sizeof(skb->cb));
+ C(len);
+ C(data_len);
+ C(csum);
+ n->cloned = 1;
+ C(pkt_type);
+ C(ip_summed);
+ C(priority);
+ atomic_set(&n->users, 1);
+ C(protocol);
+ C(security);
+ C(truesize);
+ C(head);
+ C(data);
+ C(tail);
+ C(end);
+ n->destructor = NULL;
+#ifdef CONFIG_NETFILTER
+ C(nfmark);
+ C(nfcache);
+ C(nfct);
+#ifdef CONFIG_NETFILTER_DEBUG
+ C(nf_debug);
+#endif
+#endif /*CONFIG_NETFILTER*/
+#if defined(CONFIG_HIPPI)
+ C(private);
+#endif
+#ifdef CONFIG_NET_SCHED
+ C(tc_index);
+#endif
+ C(skb_type);
+ C(net_page);
+ atomic_inc(&(skb_shinfo(skb)->dataref));
+ skb->cloned = 1;
+#ifdef CONFIG_NETFILTER
+ nf_conntrack_get(skb->nfct);
+#endif
+ return n;
+}
+
+static void copy_skb_header(struct sk_buff *new, const struct sk_buff *old)
+{
+ /*
+ * Shift between the two data areas in bytes
+ */
+ unsigned long offset = new->data - old->data;
+
+ new->list=NULL;
+ new->sk=NULL;
+ new->dev=old->dev;
+ new->priority=old->priority;
+ new->protocol=old->protocol;
+ new->dst=dst_clone(old->dst);
+ new->h.raw=old->h.raw+offset;
+ new->nh.raw=old->nh.raw+offset;
+ new->mac.raw=old->mac.raw+offset;
+ memcpy(new->cb, old->cb, sizeof(old->cb));
+ atomic_set(&new->users, 1);
+ new->pkt_type=old->pkt_type;
+ new->stamp=old->stamp;
+ new->destructor = NULL;
+ new->security=old->security;
+#ifdef CONFIG_NETFILTER
+ new->nfmark=old->nfmark;
+ new->nfcache=old->nfcache;
+ new->nfct=old->nfct;
+ nf_conntrack_get(new->nfct);
+#ifdef CONFIG_NETFILTER_DEBUG
+ new->nf_debug=old->nf_debug;
+#endif
+#endif
+#ifdef CONFIG_NET_SCHED
+ new->tc_index = old->tc_index;
+#endif
+}
+
+/**
+ * skb_copy - create private copy of an sk_buff
+ * @skb: buffer to copy
+ * @gfp_mask: allocation priority
+ *
+ * Make a copy of both an &sk_buff and its data. This is used when the
+ * caller wishes to modify the data and needs a private copy of the
+ * data to alter. Returns %NULL on failure or the pointer to the buffer
+ * on success. The returned buffer has a reference count of 1.
+ *
+ * As by-product this function converts non-linear &sk_buff to linear
+ * one, so that &sk_buff becomes completely private and caller is allowed
+ * to modify all the data of returned buffer. This means that this
+ * function is not recommended for use in circumstances when only
+ * header is going to be modified. Use pskb_copy() instead.
+ */
+
+struct sk_buff *skb_copy(const struct sk_buff *skb, int gfp_mask)
+{
+ struct sk_buff *n;
+ int headerlen = skb->data-skb->head;
+
+ /*
+ * Allocate the copy buffer
+ */
+ n=alloc_skb(skb->end - skb->head + skb->data_len, gfp_mask);
+ if(n==NULL)
+ return NULL;
+
+ /* Set the data pointer */
+ skb_reserve(n,headerlen);
+ /* Set the tail pointer and length */
+ skb_put(n,skb->len);
+ n->csum = skb->csum;
+ n->ip_summed = skb->ip_summed;
+
+ if (skb_copy_bits(skb, -headerlen, n->head, headerlen+skb->len))
+ BUG();
+
+ copy_skb_header(n, skb);
+
+ return n;
+}
+
+/* Keep head the same: replace data */
+int skb_linearize(struct sk_buff *skb, int gfp_mask)
+{
+ unsigned int size;
+ u8 *data;
+ long offset;
+ int headerlen = skb->data - skb->head;
+ int expand = (skb->tail+skb->data_len) - skb->end;
+
+ if (skb_shared(skb))
+ BUG();
+
+ if (expand <= 0)
+ expand = 0;
+
+ size = (skb->end - skb->head + expand);
+ size = SKB_DATA_ALIGN(size);
+ data = kmalloc(size + sizeof(struct skb_shared_info), gfp_mask);
+ if (data == NULL)
+ return -ENOMEM;
+
+ /* Copy entire thing */
+ if (skb_copy_bits(skb, -headerlen, data, headerlen+skb->len))
+ BUG();
+
+ /* Offset between the two in bytes */
+ offset = data - skb->head;
+
+ /* Free old data. */
+ skb_release_data(skb);
+
+ skb->head = data;
+ skb->end = data + size;
+
+ /* Set up new pointers */
+ skb->h.raw += offset;
+ skb->nh.raw += offset;
+ skb->mac.raw += offset;
+ skb->tail += offset;
+ skb->data += offset;
+
+ /* Set up shinfo */
+ atomic_set(&(skb_shinfo(skb)->dataref), 1);
+ skb_shinfo(skb)->nr_frags = 0;
+ skb_shinfo(skb)->frag_list = NULL;
+
+ /* We are no longer a clone, even if we were. */
+ skb->cloned = 0;
+
+ skb->tail += skb->data_len;
+ skb->data_len = 0;
+ return 0;
+}
+
+
+/**
+ * pskb_copy - create copy of an sk_buff with private head.
+ * @skb: buffer to copy
+ * @gfp_mask: allocation priority
+ *
+ * Make a copy of both an &sk_buff and part of its data, located
+ * in header. Fragmented data remain shared. This is used when
+ * the caller wishes to modify only header of &sk_buff and needs
+ * private copy of the header to alter. Returns %NULL on failure
+ * or the pointer to the buffer on success.
+ * The returned buffer has a reference count of 1.
+ */
+
+struct sk_buff *pskb_copy(struct sk_buff *skb, int gfp_mask)
+{
+ struct sk_buff *n;
+
+ /*
+ * Allocate the copy buffer
+ */
+ n=alloc_skb(skb->end - skb->head, gfp_mask);
+ if(n==NULL)
+ return NULL;
+
+ /* Set the data pointer */
+ skb_reserve(n,skb->data-skb->head);
+ /* Set the tail pointer and length */
+ skb_put(n,skb_headlen(skb));
+ /* Copy the bytes */
+ memcpy(n->data, skb->data, n->len);
+ n->csum = skb->csum;
+ n->ip_summed = skb->ip_summed;
+
+ n->data_len = skb->data_len;
+ n->len = skb->len;
+
+ if (skb_shinfo(skb)->nr_frags) {
+ int i;
+
+ for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
+ skb_shinfo(n)->frags[i] = skb_shinfo(skb)->frags[i];
+ get_page(skb_shinfo(n)->frags[i].page);
+ }
+ skb_shinfo(n)->nr_frags = i;
+ }
+
+ if (skb_shinfo(skb)->frag_list) {
+ skb_shinfo(n)->frag_list = skb_shinfo(skb)->frag_list;
+ skb_clone_fraglist(n);
+ }
+
+ copy_skb_header(n, skb);
+
+ return n;
+}
+
+/**
+ * pskb_expand_head - reallocate header of &sk_buff
+ * @skb: buffer to reallocate
+ * @nhead: room to add at head
+ * @ntail: room to add at tail
+ * @gfp_mask: allocation priority
+ *
+ * Expands (or creates identical copy, if &nhead and &ntail are zero)
+ * header of skb. &sk_buff itself is not changed. &sk_buff MUST have
+ * reference count of 1. Returns zero in the case of success or error,
+ * if expansion failed. In the last case, &sk_buff is not changed.
+ *
+ * All the pointers pointing into skb header may change and must be
+ * reloaded after call to this function.
+ */
+
+int pskb_expand_head(struct sk_buff *skb, int nhead, int ntail, int gfp_mask)
+{
+ int i;
+ u8 *data;
+ int size = nhead + (skb->end - skb->head) + ntail;
+ long off;
+
+ if (skb_shared(skb))
+ BUG();
+
+ size = SKB_DATA_ALIGN(size);
+
+ data = kmalloc(size + sizeof(struct skb_shared_info), gfp_mask);
+ if (data == NULL)
+ goto nodata;
+
+ /* Copy only real data... and, alas, header. This should be
+ * optimized for the cases when header is void. */
+ memcpy(data+nhead, skb->head, skb->tail-skb->head);
+ memcpy(data+size, skb->end, sizeof(struct skb_shared_info));
+
+ for (i=0; i<skb_shinfo(skb)->nr_frags; i++)
+ get_page(skb_shinfo(skb)->frags[i].page);
+
+ if (skb_shinfo(skb)->frag_list)
+ skb_clone_fraglist(skb);
+
+ skb_release_data(skb);
+
+ off = (data+nhead) - skb->head;
+
+ skb->head = data;
+ skb->end = data+size;
+
+ skb->data += off;
+ skb->tail += off;
+ skb->mac.raw += off;
+ skb->h.raw += off;
+ skb->nh.raw += off;
+ skb->cloned = 0;
+ atomic_set(&skb_shinfo(skb)->dataref, 1);
+ return 0;
+
+nodata:
+ return -ENOMEM;
+}
+
+/* Make private copy of skb with writable head and some headroom */
+
+struct sk_buff *
+skb_realloc_headroom(struct sk_buff *skb, unsigned int headroom)
+{
+ struct sk_buff *skb2;
+ int delta = headroom - skb_headroom(skb);
+
+ if (delta <= 0)
+ return pskb_copy(skb, GFP_ATOMIC);
+
+ skb2 = skb_clone(skb, GFP_ATOMIC);
+ if (skb2 == NULL ||
+ !pskb_expand_head(skb2, SKB_DATA_ALIGN(delta), 0, GFP_ATOMIC))
+ return skb2;
+
+ kfree_skb(skb2);
+ return NULL;
+}
+
+
+/**
+ * skb_copy_expand - copy and expand sk_buff
+ * @skb: buffer to copy
+ * @newheadroom: new free bytes at head
+ * @newtailroom: new free bytes at tail
+ * @gfp_mask: allocation priority
+ *
+ * Make a copy of both an &sk_buff and its data and while doing so
+ * allocate additional space.
+ *
+ * This is used when the caller wishes to modify the data and needs a
+ * private copy of the data to alter as well as more space for new fields.
+ * Returns %NULL on failure or the pointer to the buffer
+ * on success. The returned buffer has a reference count of 1.
+ *
+ * You must pass %GFP_ATOMIC as the allocation priority if this function
+ * is called from an interrupt.
+ */
+
+
+struct sk_buff *skb_copy_expand(const struct sk_buff *skb,
+ int newheadroom,
+ int newtailroom,
+ int gfp_mask)
+{
+ struct sk_buff *n;
+
+ /*
+ * Allocate the copy buffer
+ */
+
+ n=alloc_skb(newheadroom + skb->len + newtailroom,
+ gfp_mask);
+ if(n==NULL)
+ return NULL;
+
+ skb_reserve(n,newheadroom);
+
+ /* Set the tail pointer and length */
+ skb_put(n,skb->len);
+
+ /* Copy the data only. */
+ if (skb_copy_bits(skb, 0, n->data, skb->len))
+ BUG();
+
+ copy_skb_header(n, skb);
+ return n;
+}
+
+/* Trims skb to length len. It can change skb pointers, if "realloc" is 1.
+ * If realloc==0 and trimming is impossible without change of data,
+ * it is BUG().
+ */
+
+int ___pskb_trim(struct sk_buff *skb, unsigned int len, int realloc)
+{
+ int offset = skb_headlen(skb);
+ int nfrags = skb_shinfo(skb)->nr_frags;
+ int i;
+
+ for (i=0; i<nfrags; i++) {
+ int end = offset + skb_shinfo(skb)->frags[i].size;
+ if (end > len) {
+ if (skb_cloned(skb)) {
+ if (!realloc)
+ BUG();
+ if (!pskb_expand_head(skb, 0, 0, GFP_ATOMIC))
+ return -ENOMEM;
+ }
+ if (len <= offset) {
+ put_page(skb_shinfo(skb)->frags[i].page);
+ skb_shinfo(skb)->nr_frags--;
+ } else {
+ skb_shinfo(skb)->frags[i].size = len-offset;
+ }
+ }
+ offset = end;
+ }
+
+ if (offset < len) {
+ skb->data_len -= skb->len - len;
+ skb->len = len;
+ } else {
+ if (len <= skb_headlen(skb)) {
+ skb->len = len;
+ skb->data_len = 0;
+ skb->tail = skb->data + len;
+ if (skb_shinfo(skb)->frag_list && !skb_cloned(skb))
+ skb_drop_fraglist(skb);
+ } else {
+ skb->data_len -= skb->len - len;
+ skb->len = len;
+ }
+ }
+
+ return 0;
+}
+
+/**
+ * __pskb_pull_tail - advance tail of skb header
+ * @skb: buffer to reallocate
+ * @delta: number of bytes to advance tail
+ *
+ * The function makes a sense only on a fragmented &sk_buff,
+ * it expands header moving its tail forward and copying necessary
+ * data from fragmented part.
+ *
+ * &sk_buff MUST have reference count of 1.
+ *
+ * Returns %NULL (and &sk_buff does not change) if pull failed
+ * or value of new tail of skb in the case of success.
+ *
+ * All the pointers pointing into skb header may change and must be
+ * reloaded after call to this function.
+ */
+
+/* Moves tail of skb head forward, copying data from fragmented part,
+ * when it is necessary.
+ * 1. It may fail due to malloc failure.
+ * 2. It may change skb pointers.
+ *
+ * It is pretty complicated. Luckily, it is called only in exceptional cases.
+ */
+unsigned char * __pskb_pull_tail(struct sk_buff *skb, int delta)
+{
+ int i, k, eat;
+
+ /* If skb has not enough free space at tail, get new one
+ * plus 128 bytes for future expansions. If we have enough
+ * room at tail, reallocate without expansion only if skb is cloned.
+ */
+ eat = (skb->tail+delta) - skb->end;
+
+ if (eat > 0 || skb_cloned(skb)) {
+ if (pskb_expand_head(skb, 0, eat>0 ? eat+128 : 0, GFP_ATOMIC))
+ return NULL;
+ }
+
+ if (skb_copy_bits(skb, skb_headlen(skb), skb->tail, delta))
+ BUG();
+
+ /* Optimization: no fragments, no reasons to preestimate
+ * size of pulled pages. Superb.
+ */
+ if (skb_shinfo(skb)->frag_list == NULL)
+ goto pull_pages;
+
+ /* Estimate size of pulled pages. */
+ eat = delta;
+ for (i=0; i<skb_shinfo(skb)->nr_frags; i++) {
+ if (skb_shinfo(skb)->frags[i].size >= eat)
+ goto pull_pages;
+ eat -= skb_shinfo(skb)->frags[i].size;
+ }
+
+ /* If we need update frag list, we are in troubles.
+ * Certainly, it possible to add an offset to skb data,
+ * but taking into account that pulling is expected to
+ * be very rare operation, it is worth to fight against
+ * further bloating skb head and crucify ourselves here instead.
+ * Pure masohism, indeed. 8)8)
+ */
+ if (eat) {
+ struct sk_buff *list = skb_shinfo(skb)->frag_list;
+ struct sk_buff *clone = NULL;
+ struct sk_buff *insp = NULL;
+
+ do {
+ if (list == NULL)
+ BUG();
+
+ if (list->len <= eat) {
+ /* Eaten as whole. */
+ eat -= list->len;
+ list = list->next;
+ insp = list;
+ } else {
+ /* Eaten partially. */
+
+ if (skb_shared(list)) {
+ /* Sucks! We need to fork list. :-( */
+ clone = skb_clone(list, GFP_ATOMIC);
+ if (clone == NULL)
+ return NULL;
+ insp = list->next;
+ list = clone;
+ } else {
+ /* This may be pulled without
+ * problems. */
+ insp = list;
+ }
+ if (pskb_pull(list, eat) == NULL) {
+ if (clone)
+ kfree_skb(clone);
+ return NULL;
+ }
+ break;
+ }
+ } while (eat);
+
+ /* Free pulled out fragments. */
+ while ((list = skb_shinfo(skb)->frag_list) != insp) {
+ skb_shinfo(skb)->frag_list = list->next;
+ kfree_skb(list);
+ }
+ /* And insert new clone at head. */
+ if (clone) {
+ clone->next = list;
+ skb_shinfo(skb)->frag_list = clone;
+ }
+ }
+ /* Success! Now we may commit changes to skb data. */
+
+pull_pages:
+ eat = delta;
+ k = 0;
+ for (i=0; i<skb_shinfo(skb)->nr_frags; i++) {
+ if (skb_shinfo(skb)->frags[i].size <= eat) {
+ put_page(skb_shinfo(skb)->frags[i].page);
+ eat -= skb_shinfo(skb)->frags[i].size;
+ } else {
+ skb_shinfo(skb)->frags[k] = skb_shinfo(skb)->frags[i];
+ if (eat) {
+ skb_shinfo(skb)->frags[k].page_offset += eat;
+ skb_shinfo(skb)->frags[k].size -= eat;
+ eat = 0;
+ }
+ k++;
+ }
+ }
+ skb_shinfo(skb)->nr_frags = k;
+
+ skb->tail += delta;
+ skb->data_len -= delta;
+
+ return skb->tail;
+}
+
+/* Copy some data bits from skb to kernel buffer. */
+
+int skb_copy_bits(const struct sk_buff *skb, int offset, void *to, int len)
+{
+ int i, copy;
+ int start = skb->len - skb->data_len;
+
+ if (offset > (int)skb->len-len)
+ goto fault;
+
+ /* Copy header. */
+ if ((copy = start-offset) > 0) {
+ if (copy > len)
+ copy = len;
+ memcpy(to, skb->data + offset, copy);
+ if ((len -= copy) == 0)
+ return 0;
+ offset += copy;
+ to += copy;
+ }
+
+ for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
+ int end;
+
+ BUG_TRAP(start <= offset+len);
+
+ end = start + skb_shinfo(skb)->frags[i].size;
+ if ((copy = end-offset) > 0) {
+ u8 *vaddr;
+
+ if (copy > len)
+ copy = len;
+
+ vaddr = kmap_skb_frag(&skb_shinfo(skb)->frags[i]);
+ memcpy(to, vaddr+skb_shinfo(skb)->frags[i].page_offset+
+ offset-start, copy);
+ kunmap_skb_frag(vaddr);
+
+ if ((len -= copy) == 0)
+ return 0;
+ offset += copy;
+ to += copy;
+ }
+ start = end;
+ }
+
+ if (skb_shinfo(skb)->frag_list) {
+ struct sk_buff *list;
+
+ for (list = skb_shinfo(skb)->frag_list; list; list=list->next) {
+ int end;
+
+ BUG_TRAP(start <= offset+len);
+
+ end = start + list->len;
+ if ((copy = end-offset) > 0) {
+ if (copy > len)
+ copy = len;
+ if (skb_copy_bits(list, offset-start, to, copy))
+ goto fault;
+ if ((len -= copy) == 0)
+ return 0;
+ offset += copy;
+ to += copy;
+ }
+ start = end;
+ }
+ }
+ if (len == 0)
+ return 0;
+
+fault:
+ return -EFAULT;
+}
+
+/* Checksum skb data. */
+
+unsigned int skb_checksum(const struct sk_buff *skb, int offset, int len, unsigned int csum)
+{
+ int i, copy;
+ int start = skb->len - skb->data_len;
+ int pos = 0;
+
+ /* Checksum header. */
+ if ((copy = start-offset) > 0) {
+ if (copy > len)
+ copy = len;
+ csum = csum_partial(skb->data+offset, copy, csum);
+ if ((len -= copy) == 0)
+ return csum;
+ offset += copy;
+ pos = copy;
+ }
+
+ for (i=0; i<skb_shinfo(skb)->nr_frags; i++) {
+ int end;
+
+ BUG_TRAP(start <= offset+len);
+
+ end = start + skb_shinfo(skb)->frags[i].size;
+ if ((copy = end-offset) > 0) {
+ unsigned int csum2;
+ u8 *vaddr;
+ skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
+
+ if (copy > len)
+ copy = len;
+ vaddr = kmap_skb_frag(frag);
+ csum2 = csum_partial(vaddr + frag->page_offset +
+ offset-start, copy, 0);
+ kunmap_skb_frag(vaddr);
+ csum = csum_block_add(csum, csum2, pos);
+ if (!(len -= copy))
+ return csum;
+ offset += copy;
+ pos += copy;
+ }
+ start = end;
+ }
+
+ if (skb_shinfo(skb)->frag_list) {
+ struct sk_buff *list;
+
+ for (list = skb_shinfo(skb)->frag_list; list; list=list->next) {
+ int end;
+
+ BUG_TRAP(start <= offset+len);
+
+ end = start + list->len;
+ if ((copy = end-offset) > 0) {
+ unsigned int csum2;
+ if (copy > len)
+ copy = len;
+ csum2 = skb_checksum(list, offset-start, copy, 0);
+ csum = csum_block_add(csum, csum2, pos);
+ if ((len -= copy) == 0)
+ return csum;
+ offset += copy;
+ pos += copy;
+ }
+ start = end;
+ }
+ }
+ if (len == 0)
+ return csum;
+
+ BUG();
+ return csum;
+}
+
+/* Both of above in one bottle. */
+
+unsigned int skb_copy_and_csum_bits(const struct sk_buff *skb, int offset, u8 *to, int len, unsigned int csum)
+{
+ int i, copy;
+ int start = skb->len - skb->data_len;
+ int pos = 0;
+
+ /* Copy header. */
+ if ((copy = start-offset) > 0) {
+ if (copy > len)
+ copy = len;
+ csum = csum_partial_copy_nocheck(skb->data+offset, to, copy, csum);
+ if ((len -= copy) == 0)
+ return csum;
+ offset += copy;
+ to += copy;
+ pos = copy;
+ }
+
+ for (i=0; i<skb_shinfo(skb)->nr_frags; i++) {
+ int end;
+
+ BUG_TRAP(start <= offset+len);
+
+ end = start + skb_shinfo(skb)->frags[i].size;
+ if ((copy = end-offset) > 0) {
+ unsigned int csum2;
+ u8 *vaddr;
+ skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
+
+ if (copy > len)
+ copy = len;
+ vaddr = kmap_skb_frag(frag);
+ csum2 = csum_partial_copy_nocheck(vaddr + frag->page_offset +
+ offset-start, to, copy, 0);
+ kunmap_skb_frag(vaddr);
+ csum = csum_block_add(csum, csum2, pos);
+ if (!(len -= copy))
+ return csum;
+ offset += copy;
+ to += copy;
+ pos += copy;
+ }
+ start = end;
+ }
+
+ if (skb_shinfo(skb)->frag_list) {
+ struct sk_buff *list;
+
+ for (list = skb_shinfo(skb)->frag_list; list; list=list->next) {
+ unsigned int csum2;
+ int end;
+
+ BUG_TRAP(start <= offset+len);
+
+ end = start + list->len;
+ if ((copy = end-offset) > 0) {
+ if (copy > len)
+ copy = len;
+ csum2 = skb_copy_and_csum_bits(list, offset-start, to, copy, 0);
+ csum = csum_block_add(csum, csum2, pos);
+ if ((len -= copy) == 0)
+ return csum;
+ offset += copy;
+ to += copy;
+ pos += copy;
+ }
+ start = end;
+ }
+ }
+ if (len == 0)
+ return csum;
+
+ BUG();
+ return csum;
+}
+
+void skb_copy_and_csum_dev(const struct sk_buff *skb, u8 *to)
+{
+ unsigned int csum;
+ long csstart;
+
+ if (skb->ip_summed == CHECKSUM_HW)
+ csstart = skb->h.raw - skb->data;
+ else
+ csstart = skb->len - skb->data_len;
+
+ if (csstart > skb->len - skb->data_len)
+ BUG();
+
+ memcpy(to, skb->data, csstart);
+
+ csum = 0;
+ if (csstart != skb->len)
+ csum = skb_copy_and_csum_bits(skb, csstart, to+csstart,
+ skb->len-csstart, 0);
+
+ if (skb->ip_summed == CHECKSUM_HW) {
+ long csstuff = csstart + skb->csum;
+
+ *((unsigned short *)(to + csstuff)) = csum_fold(csum);
+ }
+}
+
+#if 0
+/*
+ * Tune the memory allocator for a new MTU size.
+ */
+void skb_add_mtu(int mtu)
+{
+ /* Must match allocation in alloc_skb */
+ mtu = SKB_DATA_ALIGN(mtu) + sizeof(struct skb_shared_info);
+
+ kmem_add_cache_size(mtu);
+}
+#endif
+
+void __init skb_init(void)
+{
+ int i;
+
+ skbuff_head_cache = kmem_cache_create("skbuff_head_cache",
+ sizeof(struct sk_buff),
+ 0,
+ SLAB_HWCACHE_ALIGN,
+ skb_headerinit, NULL);
+ if (!skbuff_head_cache)
+ panic("cannot create skbuff cache");
+
+ init_net_pages(NUM_NET_PAGES);
+
+ for (i=0; i<NR_CPUS; i++)
+ skb_queue_head_init(&skb_head_pool[i].list);
+}
projects / xen.git / commitdiff