--- /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/compiler.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>
+#include <linux/poll.h>
+#include <linux/net.h>
+#include <net/checksum.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
+
+struct net_device;
+
+#ifdef CONFIG_NETFILTER
+struct nf_conntrack {
+ atomic_t use;
+ void (*destroy)(struct nf_conntrack *);
+};
+
+#ifdef CONFIG_BRIDGE_NETFILTER
+struct nf_bridge_info {
+ atomic_t use;
+ struct net_device *physindev;
+ struct net_device *physoutdev;
+#if defined(CONFIG_VLAN_8021Q) || defined(CONFIG_VLAN_8021Q_MODULE)
+ struct net_device *netoutdev;
+#endif
+ unsigned int mask;
+ unsigned long data[32 / sizeof(unsigned long)];
+};
+#endif
+
+#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;
+
+/* To allow 64K frame to be packed as single skb without frag_list */
+#define MAX_SKB_FRAGS (65536/PAGE_SIZE + 2)
+
+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;
+ unsigned short tso_size;
+ unsigned short tso_segs;
+ struct sk_buff *frag_list;
+ skb_frag_t frags[MAX_SKB_FRAGS];
+};
+
+/**
+ * struct sk_buff - socket buffer
+ * @next: Next buffer in list
+ * @prev: Previous buffer in list
+ * @list: List we are on
+ * @sk: Socket we are owned by
+ * @stamp: Time we arrived
+ * @dev: Device we arrived on/are leaving by
+ * @input_dev: Device we arrived on
+ * @real_dev: The real device we are using
+ * @h: Transport layer header
+ * @nh: Network layer header
+ * @mac: Link layer header
+ * @dst: FIXME: Describe this field
+ * @cb: Control buffer. Free for use by every layer. Put private vars here
+ * @len: Length of actual data
+ * @data_len: Data length
+ * @mac_len: Length of link layer header
+ * @csum: Checksum
+ * @__unused: Dead field, may be reused
+ * @cloned: Head may be cloned (check refcnt to be sure)
+ * @proto_csum_valid: Protocol csum validated since arriving at localhost
+ * @proto_csum_blank: Protocol csum must be added before leaving localhost
+ * @pkt_type: Packet class
+ * @ip_summed: Driver fed us an IP checksum
+ * @priority: Packet queueing priority
+ * @users: User count - see {datagram,tcp}.c
+ * @protocol: Packet protocol from driver
+ * @security: Security level of packet
+ * @truesize: Buffer size
+ * @head: Head of buffer
+ * @data: Data head pointer
+ * @tail: Tail pointer
+ * @end: End pointer
+ * @destructor: Destruct function
+ * @nfmark: Can be used for communication between hooks
+ * @nfcache: Cache info
+ * @nfct: Associated connection, if any
+ * @nfctinfo: Relationship of this skb to the connection
+ * @nf_debug: Netfilter debugging
+ * @nf_bridge: Saved data about a bridged frame - see br_netfilter.c
+ * @private: Data which is private to the HIPPI implementation
+ * @tc_index: Traffic control index
+ */
+
+struct sk_buff {
+ /* These two members must be first. */
+ struct sk_buff *next;
+ struct sk_buff *prev;
+
+ struct sk_buff_head *list;
+ struct sock *sk;
+ struct timeval stamp;
+ struct net_device *dev;
+ struct net_device *input_dev;
+ struct net_device *real_dev;
+
+ union {
+ struct tcphdr *th;
+ struct udphdr *uh;
+ struct icmphdr *icmph;
+ struct igmphdr *igmph;
+ struct iphdr *ipiph;
+ struct ipv6hdr *ipv6h;
+ unsigned char *raw;
+ } h;
+
+ union {
+ struct iphdr *iph;
+ struct ipv6hdr *ipv6h;
+ struct arphdr *arph;
+ unsigned char *raw;
+ } nh;
+
+ union {
+ unsigned char *raw;
+ } mac;
+
+ struct dst_entry *dst;
+ struct sec_path *sp;
+
+ /*
+ * 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[40];
+
+ unsigned int len,
+ data_len,
+ mac_len,
+ csum;
+ unsigned char local_df,
+ cloned:1,
+ proto_csum_valid:1,
+ proto_csum_blank:1,
+ pkt_type,
+ ip_summed;
+ __u32 priority;
+ unsigned short protocol,
+ security;
+
+ void (*destructor)(struct sk_buff *skb);
+#ifdef CONFIG_NETFILTER
+ unsigned long nfmark;
+ __u32 nfcache;
+ __u32 nfctinfo;
+ struct nf_conntrack *nfct;
+#ifdef CONFIG_NETFILTER_DEBUG
+ unsigned int nf_debug;
+#endif
+#ifdef CONFIG_BRIDGE_NETFILTER
+ struct nf_bridge_info *nf_bridge;
+#endif
+#endif /* CONFIG_NETFILTER */
+#if defined(CONFIG_HIPPI)
+ union {
+ __u32 ifield;
+ } private;
+#endif
+#ifdef CONFIG_NET_SCHED
+ __u32 tc_index; /* traffic control index */
+#ifdef CONFIG_NET_CLS_ACT
+ __u32 tc_verd; /* traffic control verdict */
+ __u32 tc_classid; /* traffic control classid */
+#endif
+
+#endif
+
+
+ /* These elements must be at the end, see alloc_skb() for details. */
+ unsigned int truesize;
+ atomic_t users;
+ unsigned char *head,
+ *data,
+ *tail,
+ *end;
+};
+
+#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_skb_from_cache(kmem_cache_t *cp,
+ 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(const 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 (likely(atomic_read(&skb->users) == 1))
+ smp_rmb();
+ else if (likely(!atomic_dec_and_test(&skb->users)))
+ return;
+ __kfree_skb(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(const 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(const struct sk_buff *skb)
+{
+ return atomic_read(&skb->users) != 1;
+}
+
+/**
+ * skb_share_check - check if buffer is shared and if so clone it
+ * @skb: buffer to check
+ * @pri: priority for memory allocation
+ *
+ * If the buffer is shared the buffer is cloned and the old copy
+ * drops a reference. A new clone with a single reference is returned.
+ * If the buffer is not shared the original buffer is returned. When
+ * being called from interrupt status or with spinlocks held pri must
+ * be GFP_ATOMIC.
+ *
+ * NULL is returned on a memory allocation failure.
+ */
+static inline struct sk_buff *skb_share_check(struct sk_buff *skb, int pri)
+{
+ might_sleep_if(pri & __GFP_WAIT);
+ if (skb_shared(skb)) {
+ struct sk_buff *nskb = skb_clone(skb, pri);
+ kfree_skb(skb);
+ skb = nskb;
+ }
+ return skb;
+}
+
+/*
+ * Copy shared buffers into a new sk_buff. We effectively do COW on
+ * packets to handle cases where we have a local reader and forward
+ * and a couple of other messy ones. The normal one is tcpdumping
+ * a packet thats being forwarded.
+ */
+
+/**
+ * skb_unshare - make a copy of a shared buffer
+ * @skb: buffer to check
+ * @pri: priority for memory allocation
+ *
+ * If the socket buffer is a clone then this function creates a new
+ * copy of the data, drops a reference count on the old copy and returns
+ * the new copy with the reference count at 1. If the buffer is not a clone
+ * the original buffer is returned. When called with a spinlock held or
+ * from interrupt state @pri must be %GFP_ATOMIC
+ *
+ * %NULL is returned on a memory allocation failure.
+ */
+static inline struct sk_buff *skb_unshare(struct sk_buff *skb, int pri)
+{
+ might_sleep_if(pri & __GFP_WAIT);
+ if (skb_cloned(skb)) {
+ struct sk_buff *nskb = skb_copy(skb, pri);
+ kfree_skb(skb); /* Free our shared copy */
+ skb = nskb;
+ }
+ return skb;
+}
+
+/**
+ * skb_peek
+ * @list_: list to peek at
+ *
+ * Peek an &sk_buff. Unlike most other operations you _MUST_
+ * be careful with this one. A peek leaves the buffer on the
+ * list and someone else may run off with it. You must hold
+ * the appropriate locks or have a private queue to do this.
+ *
+ * Returns %NULL for an empty list or a pointer to the head element.
+ * The reference count is not incremented and the reference is therefore
+ * volatile. Use with caution.
+ */
+static inline struct sk_buff *skb_peek(struct sk_buff_head *list_)
+{
+ struct sk_buff *list = ((struct sk_buff *)list_)->next;
+ if (list == (struct sk_buff *)list_)
+ list = NULL;
+ return list;
+}
+
+/**
+ * skb_peek_tail
+ * @list_: list to peek at
+ *
+ * Peek an &sk_buff. Unlike most other operations you _MUST_
+ * be careful with this one. A peek leaves the buffer on the
+ * list and someone else may run off with it. You must hold
+ * the appropriate locks or have a private queue to do this.
+ *
+ * Returns %NULL for an empty list or a pointer to the tail element.
+ * The reference count is not incremented and the reference is therefore
+ * volatile. Use with caution.
+ */
+static inline struct sk_buff *skb_peek_tail(struct sk_buff_head *list_)
+{
+ struct sk_buff *list = ((struct sk_buff *)list_)->prev;
+ if (list == (struct sk_buff *)list_)
+ list = NULL;
+ return list;
+}
+
+/**
+ * skb_queue_len - get queue length
+ * @list_: list to measure
+ *
+ * Return the length of an &sk_buff queue.
+ */
+static inline __u32 skb_queue_len(const struct sk_buff_head *list_)
+{
+ return list_->qlen;
+}
+
+static inline void skb_queue_head_init(struct sk_buff_head *list)
+{
+ spin_lock_init(&list->lock);
+ list->prev = list->next = (struct sk_buff *)list;
+ list->qlen = 0;
+}
+
+/*
+ * Insert an sk_buff at the start of a list.
+ *
+ * The "__skb_xxxx()" functions are the non-atomic ones that
+ * can only be called with interrupts disabled.
+ */
+
+/**
+ * __skb_queue_head - queue a buffer at the list head
+ * @list: list to use
+ * @newsk: buffer to queue
+ *
+ * Queue a buffer at the start of a list. This function takes no locks
+ * and you must therefore hold required locks before calling it.
+ *
+ * A buffer cannot be placed on two lists at the same time.
+ */
+extern void skb_queue_head(struct sk_buff_head *list, struct sk_buff *newsk);
+static inline void __skb_queue_head(struct sk_buff_head *list,
+ struct sk_buff *newsk)
+{
+ 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 = 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 end of a list. This function takes no locks
+ * and you must therefore hold required locks before calling it.
+ *
+ * A buffer cannot be placed on two lists at the same time.
+ */
+extern void skb_queue_tail(struct sk_buff_head *list, struct sk_buff *newsk);
+static inline void __skb_queue_tail(struct sk_buff_head *list,
+ struct sk_buff *newsk)
+{
+ struct sk_buff *prev, *next;
+
+ newsk->list = list;
+ list->qlen++;
+ next = (struct sk_buff *)list;
+ prev = next->prev;
+ newsk->next = next;
+ newsk->prev = prev;
+ next->prev = prev->next = newsk;
+}
+
+
+/**
+ * __skb_dequeue - remove from the head of the queue
+ * @list: list to dequeue from
+ *
+ * Remove the head of the list. This function does not take any locks
+ * so must be used with appropriate locks held only. The head item is
+ * returned or %NULL if the list is empty.
+ */
+extern struct sk_buff *skb_dequeue(struct sk_buff_head *list);
+static inline struct sk_buff *__skb_dequeue(struct sk_buff_head *list)
+{
+ struct sk_buff *next, *prev, *result;
+
+ prev = (struct sk_buff *) list;
+ next = prev->next;
+ result = NULL;
+ if (next != prev) {
+ result = next;
+ next = next->next;
+ list->qlen--;
+ next->prev = prev;
+ prev->next = next;
+ result->next = result->prev = NULL;
+ result->list = NULL;
+ }
+ return result;
+}
+
+
+/*
+ * Insert a packet on a list.
+ */
+extern void skb_insert(struct sk_buff *old, struct sk_buff *newsk);
+static inline void __skb_insert(struct sk_buff *newsk,
+ struct sk_buff *prev, struct sk_buff *next,
+ struct sk_buff_head *list)
+{
+ newsk->next = next;
+ newsk->prev = prev;
+ next->prev = prev->next = newsk;
+ newsk->list = list;
+ list->qlen++;
+}
+
+/*
+ * Place a packet after a given packet in a list.
+ */
+extern void skb_append(struct sk_buff *old, struct sk_buff *newsk);
+static inline void __skb_append(struct sk_buff *old, struct sk_buff *newsk)
+{
+ __skb_insert(newsk, old, old->next, old->list);
+}
+
+/*
+ * remove sk_buff from list. _Must_ be called atomically, and with
+ * the list known..
+ */
+extern void skb_unlink(struct sk_buff *skb);
+static inline void __skb_unlink(struct sk_buff *skb, struct sk_buff_head *list)
+{
+ struct sk_buff *next, *prev;
+
+ list->qlen--;
+ next = skb->next;
+ prev = skb->prev;
+ skb->next = skb->prev = NULL;
+ skb->list = NULL;
+ next->prev = prev;
+ prev->next = next;
+}
+
+
+/* XXX: more streamlined implementation */
+
+/**
+ * __skb_dequeue_tail - remove from the tail of the queue
+ * @list: list to dequeue from
+ *
+ * Remove the tail of the list. This function does not take any locks
+ * so must be used with appropriate locks held only. The tail item is
+ * returned or %NULL if the list is empty.
+ */
+extern struct sk_buff *skb_dequeue_tail(struct sk_buff_head *list);
+static inline struct sk_buff *__skb_dequeue_tail(struct sk_buff_head *list)
+{
+ struct sk_buff *skb = skb_peek_tail(list);
+ if (skb)
+ __skb_unlink(skb, list);
+ return skb;
+}
+
+
+static inline int skb_is_nonlinear(const struct sk_buff *skb)
+{
+ return skb->data_len;
+}
+
+static inline unsigned int skb_headlen(const struct sk_buff *skb)
+{
+ return skb->len - skb->data_len;
+}
+
+static inline int skb_pagelen(const struct sk_buff *skb)
+{
+ int i, len = 0;
+
+ for (i = (int)skb_shinfo(skb)->nr_frags - 1; i >= 0; i--)
+ len += skb_shinfo(skb)->frags[i].size;
+ return len + skb_headlen(skb);
+}
+
+static inline void skb_fill_page_desc(struct sk_buff *skb, int i,
+ struct page *page, int off, int size)
+{
+ skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
+
+ frag->page = page;
+ frag->page_offset = off;
+ frag->size = size;
+ skb_shinfo(skb)->nr_frags = i + 1;
+}
+
+#define SKB_PAGE_ASSERT(skb) BUG_ON(skb_shinfo(skb)->nr_frags)
+#define SKB_FRAG_ASSERT(skb) BUG_ON(skb_shinfo(skb)->frag_list)
+#define SKB_LINEAR_ASSERT(skb) BUG_ON(skb_is_nonlinear(skb))
+
+/*
+ * Add data to an sk_buff
+ */
+static inline unsigned char *__skb_put(struct sk_buff *skb, unsigned int len)
+{
+ unsigned char *tmp = skb->tail;
+ SKB_LINEAR_ASSERT(skb);
+ skb->tail += len;
+ skb->len += len;
+ return tmp;
+}
+
+/**
+ * skb_put - add data to a buffer
+ * @skb: buffer to use
+ * @len: amount of data to add
+ *
+ * This function extends the used data area of the buffer. If this would
+ * exceed the total buffer size the kernel will panic. A pointer to the
+ * first byte of the extra data is returned.
+ */
+static inline unsigned char *skb_put(struct sk_buff *skb, unsigned int len)
+{
+ unsigned char *tmp = skb->tail;
+ SKB_LINEAR_ASSERT(skb);
+ skb->tail += len;
+ skb->len += len;
+ if (unlikely(skb->tail>skb->end))
+ skb_over_panic(skb, len, current_text_addr());
+ return tmp;
+}
+
+static inline unsigned char *__skb_push(struct sk_buff *skb, unsigned int len)
+{
+ skb->data -= len;
+ skb->len += len;
+ return skb->data;
+}
+
+/**
+ * skb_push - add data to the start of a buffer
+ * @skb: buffer to use
+ * @len: amount of data to add
+ *
+ * This function extends the used data area of the buffer at the buffer
+ * start. If this would exceed the total buffer headroom the kernel will
+ * panic. A pointer to the first byte of the extra data is returned.
+ */
+static inline unsigned char *skb_push(struct sk_buff *skb, unsigned int len)
+{
+ skb->data -= len;
+ skb->len += len;
+ if (unlikely(skb->data<skb->head))
+ skb_under_panic(skb, len, current_text_addr());
+ return skb->data;
+}
+
+static inline unsigned char *__skb_pull(struct sk_buff *skb, unsigned int len)
+{
+ skb->len -= len;
+ BUG_ON(skb->len < skb->data_len);
+ return skb->data += len;
+}
+
+/**
+ * skb_pull - remove data from the start of a buffer
+ * @skb: buffer to use
+ * @len: amount of data to remove
+ *
+ * This function removes data from the start of a buffer, returning
+ * the memory to the headroom. A pointer to the next data in the buffer
+ * is returned. Once the data has been pulled future pushes will overwrite
+ * the old data.
+ */
+static inline unsigned char *skb_pull(struct sk_buff *skb, unsigned int len)
+{
+ return unlikely(len > skb->len) ? NULL : __skb_pull(skb, len);
+}
+
+extern unsigned char *__pskb_pull_tail(struct sk_buff *skb, int delta);
+
+static inline unsigned char *__pskb_pull(struct sk_buff *skb, unsigned int len)
+{
+ if (len > skb_headlen(skb) &&
+ !__pskb_pull_tail(skb, len-skb_headlen(skb)))
+ return NULL;
+ skb->len -= len;
+ return skb->data += len;
+}
+
+static inline unsigned char *pskb_pull(struct sk_buff *skb, unsigned int len)
+{
+ return unlikely(len > skb->len) ? NULL : __pskb_pull(skb, len);
+}
+
+static inline int pskb_may_pull(struct sk_buff *skb, unsigned int len)
+{
+ if (likely(len <= skb_headlen(skb)))
+ return 1;
+ if (unlikely(len > skb->len))
+ return 0;
+ return __pskb_pull_tail(skb, len-skb_headlen(skb)) != NULL;
+}
+
+/**
+ * skb_headroom - bytes at buffer head
+ * @skb: buffer to check
+ *
+ * Return the number of bytes of free space at the head of an &sk_buff.
+ */
+static inline int skb_headroom(const struct sk_buff *skb)
+{
+ return skb->data - skb->head;
+}
+
+/**
+ * skb_tailroom - bytes at buffer end
+ * @skb: buffer to check
+ *
+ * Return the number of bytes of free space at the tail of an sk_buff
+ */
+static inline int skb_tailroom(const struct sk_buff *skb)
+{
+ return skb_is_nonlinear(skb) ? 0 : skb->end - skb->tail;
+}
+
+/**
+ * skb_reserve - adjust headroom
+ * @skb: buffer to alter
+ * @len: bytes to move
+ *
+ * Increase the headroom of an empty &sk_buff by reducing the tail
+ * room. This is only allowed for an empty buffer.
+ */
+static inline void skb_reserve(struct sk_buff *skb, unsigned int len)
+{
+ skb->data += len;
+ skb->tail += len;
+}
+
+/*
+ * CPUs often take a performance hit when accessing unaligned memory
+ * locations. The actual performance hit varies, it can be small if the
+ * hardware handles it or large if we have to take an exception and fix it
+ * in software.
+ *
+ * Since an ethernet header is 14 bytes network drivers often end up with
+ * the IP header at an unaligned offset. The IP header can be aligned by
+ * shifting the start of the packet by 2 bytes. Drivers should do this
+ * with:
+ *
+ * skb_reserve(NET_IP_ALIGN);
+ *
+ * The downside to this alignment of the IP header is that the DMA is now
+ * unaligned. On some architectures the cost of an unaligned DMA is high
+ * and this cost outweighs the gains made by aligning the IP header.
+ *
+ * Since this trade off varies between architectures, we allow NET_IP_ALIGN
+ * to be overridden.
+ */
+#ifndef NET_IP_ALIGN
+#define NET_IP_ALIGN 2
+#endif
+
+extern int ___pskb_trim(struct sk_buff *skb, unsigned int len, int realloc);
+
+static inline void __skb_trim(struct sk_buff *skb, unsigned int len)
+{
+ if (!skb->data_len) {
+ skb->len = len;
+ skb->tail = skb->data + len;
+ } else
+ ___pskb_trim(skb, len, 0);
+}
+
+/**
+ * skb_trim - remove end from a buffer
+ * @skb: buffer to alter
+ * @len: new length
+ *
+ * Cut the length of a buffer down by removing data from the tail. If
+ * the buffer is already under the length specified it is not modified.
+ */
+static inline void skb_trim(struct sk_buff *skb, unsigned int len)
+{
+ if (skb->len > len)
+ __skb_trim(skb, len);
+}
+
+
+static inline int __pskb_trim(struct sk_buff *skb, unsigned int len)
+{
+ if (!skb->data_len) {
+ skb->len = len;
+ skb->tail = skb->data+len;
+ return 0;
+ }
+ return ___pskb_trim(skb, len, 1);
+}
+
+static inline int pskb_trim(struct sk_buff *skb, unsigned int len)
+{
+ return (len < skb->len) ? __pskb_trim(skb, len) : 0;
+}
+
+/**
+ * skb_orphan - orphan a buffer
+ * @skb: buffer to orphan
+ *
+ * If a buffer currently has an owner then we call the owner's
+ * destructor function and make the @skb unowned. The buffer continues
+ * to exist but is no longer charged to its former owner.
+ */
+static inline void skb_orphan(struct sk_buff *skb)
+{
+ if (skb->destructor)
+ skb->destructor(skb);
+ skb->destructor = NULL;
+ skb->sk = NULL;
+}
+
+/**
+ * __skb_queue_purge - empty a list
+ * @list: list to empty
+ *
+ * Delete all buffers on an &sk_buff list. Each buffer is removed from
+ * the list and one reference dropped. This function does not take the
+ * list lock and the caller must hold the relevant locks to use it.
+ */
+extern void skb_queue_purge(struct sk_buff_head *list);
+static inline void __skb_queue_purge(struct sk_buff_head *list)
+{
+ struct sk_buff *skb;
+ while ((skb = __skb_dequeue(list)) != NULL)
+ kfree_skb(skb);
+}
+
+/**
+ * __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.
+ */
+#ifndef CONFIG_HAVE_ARCH_DEV_ALLOC_SKB
+static inline struct sk_buff *__dev_alloc_skb(unsigned int length,
+ int gfp_mask)
+{
+ struct sk_buff *skb = alloc_skb(length + 16, gfp_mask);
+ if (likely(skb))
+ skb_reserve(skb, 16);
+ return skb;
+}
+#else
+extern struct sk_buff *__dev_alloc_skb(unsigned int length, int gfp_mask);
+#endif
+
+/**
+ * dev_alloc_skb - allocate an skbuff for sending
+ * @length: length to allocate
+ *
+ * Allocate a new &sk_buff and assign it a usage count of one. The
+ * buffer has unspecified headroom built in. Users should allocate
+ * the headroom they think they need without accounting for the
+ * built in space. The built in space is used for optimisations.
+ *
+ * %NULL is returned in there is no free memory. Although this function
+ * allocates memory it can be called from an interrupt.
+ */
+static inline struct sk_buff *dev_alloc_skb(unsigned int length)
+{
+ return __dev_alloc_skb(length, GFP_ATOMIC);
+}
+
+/**
+ * skb_cow - copy header of skb when it is required
+ * @skb: buffer to cow
+ * @headroom: needed headroom
+ *
+ * If the skb passed lacks sufficient headroom or its data part
+ * is shared, data is reallocated. If reallocation fails, an error
+ * is returned and original skb is not changed.
+ *
+ * The result is skb with writable area skb->head...skb->tail
+ * and at least @headroom of space at head.
+ */
+static inline int skb_cow(struct sk_buff *skb, unsigned int headroom)
+{
+ int delta = (headroom > 16 ? headroom : 16) - skb_headroom(skb);
+
+ if (delta < 0)
+ delta = 0;
+
+ if (delta || skb_cloned(skb))
+ return pskb_expand_head(skb, (delta + 15) & ~15, 0, GFP_ATOMIC);
+ return 0;
+}
+
+/**
+ * skb_padto - pad an skbuff up to a minimal size
+ * @skb: buffer to pad
+ * @len: minimal length
+ *
+ * Pads up a buffer to ensure the trailing bytes exist and are
+ * blanked. If the buffer already contains sufficient data it
+ * is untouched. Returns the buffer, which may be a replacement
+ * for the original, or NULL for out of memory - in which case
+ * the original buffer is still freed.
+ */
+
+static inline struct sk_buff *skb_padto(struct sk_buff *skb, unsigned int len)
+{
+ unsigned int size = skb->len;
+ if (likely(size >= len))
+ return skb;
+ return skb_pad(skb, len-size);
+}
+
+static inline int skb_add_data(struct sk_buff *skb,
+ char __user *from, int copy)
+{
+ const int off = skb->len;
+
+ if (skb->ip_summed == CHECKSUM_NONE) {
+ int err = 0;
+ unsigned int csum = csum_and_copy_from_user(from,
+ skb_put(skb, copy),
+ copy, 0, &err);
+ if (!err) {
+ skb->csum = csum_block_add(skb->csum, csum, off);
+ return 0;
+ }
+ } else if (!copy_from_user(skb_put(skb, copy), from, copy))
+ return 0;
+
+ __skb_trim(skb, off);
+ return -EFAULT;
+}
+
+static inline int skb_can_coalesce(struct sk_buff *skb, int i,
+ struct page *page, int off)
+{
+ if (i) {
+ struct skb_frag_struct *frag = &skb_shinfo(skb)->frags[i - 1];
+
+ return page == frag->page &&
+ off == frag->page_offset + frag->size;
+ }
+ return 0;
+}
+
+/**
+ * skb_linearize - convert paged skb to linear one
+ * @skb: buffer to linarize
+ * @gfp: allocation mode
+ *
+ * If there is no free memory -ENOMEM is returned, otherwise zero
+ * is returned and the old skb data released.
+ */
+extern int __skb_linearize(struct sk_buff *skb, int gfp);
+static inline int skb_linearize(struct sk_buff *skb, int gfp)
+{
+ return __skb_linearize(skb, gfp);
+}
+
+static inline void *kmap_skb_frag(const skb_frag_t *frag)
+{
+#ifdef CONFIG_HIGHMEM
+ BUG_ON(in_irq());
+
+ local_bh_disable();
+#endif
+ return kmap_atomic(frag->page, KM_SKB_DATA_SOFTIRQ);
+}
+
+static inline void kunmap_skb_frag(void *vaddr)
+{
+ kunmap_atomic(vaddr, KM_SKB_DATA_SOFTIRQ);
+#ifdef CONFIG_HIGHMEM
+ local_bh_enable();
+#endif
+}
+
+#define skb_queue_walk(queue, skb) \
+ for (skb = (queue)->next; \
+ prefetch(skb->next), (skb != (struct sk_buff *)(queue)); \
+ skb = skb->next)
+
+
+extern struct sk_buff *skb_recv_datagram(struct sock *sk, unsigned flags,
+ int noblock, int *err);
+extern unsigned int datagram_poll(struct file *file, struct socket *sock,
+ struct poll_table_struct *wait);
+extern int skb_copy_datagram_iovec(const struct sk_buff *from,
+ int offset, struct iovec *to,
+ int size);
+extern int skb_copy_and_csum_datagram_iovec(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_split(struct sk_buff *skb,
+ struct sk_buff *skb1, const u32 len);
+
+static inline void *skb_header_pointer(const struct sk_buff *skb, int offset,
+ int len, void *buffer)
+{
+ int hlen = skb_headlen(skb);
+
+ if (offset + len <= hlen)
+ return skb->data + offset;
+
+ if (skb_copy_bits(skb, offset, buffer, len) < 0)
+ return NULL;
+
+ return buffer;
+}
+
+extern void skb_init(void);
+extern void skb_add_mtu(int mtu);
+
+struct skb_iter {
+ /* Iteration functions set these */
+ unsigned char *data;
+ unsigned int len;
+
+ /* Private to iteration */
+ unsigned int nextfrag;
+ struct sk_buff *fraglist;
+};
+
+/* Keep iterating until skb_iter_next returns false. */
+extern void skb_iter_first(const struct sk_buff *skb, struct skb_iter *i);
+extern int skb_iter_next(const struct sk_buff *skb, struct skb_iter *i);
+/* Call this if aborting loop before !skb_iter_next */
+extern void skb_iter_abort(const struct sk_buff *skb, struct skb_iter *i);
+
+#ifdef CONFIG_NETFILTER
+static inline void nf_conntrack_put(struct nf_conntrack *nfct)
+{
+ if (nfct && atomic_dec_and_test(&nfct->use))
+ nfct->destroy(nfct);
+}
+static inline void nf_conntrack_get(struct nf_conntrack *nfct)
+{
+ if (nfct)
+ atomic_inc(&nfct->use);
+}
+static inline void nf_reset(struct sk_buff *skb)
+{
+ nf_conntrack_put(skb->nfct);
+ skb->nfct = NULL;
+#ifdef CONFIG_NETFILTER_DEBUG
+ skb->nf_debug = 0;
+#endif
+}
+static inline void nf_reset_debug(struct sk_buff *skb)
+{
+#ifdef CONFIG_NETFILTER_DEBUG
+ skb->nf_debug = 0;
+#endif
+}
+
+#ifdef CONFIG_BRIDGE_NETFILTER
+static inline void nf_bridge_put(struct nf_bridge_info *nf_bridge)
+{
+ if (nf_bridge && atomic_dec_and_test(&nf_bridge->use))
+ kfree(nf_bridge);
+}
+static inline void nf_bridge_get(struct nf_bridge_info *nf_bridge)
+{
+ if (nf_bridge)
+ atomic_inc(&nf_bridge->use);
+}
+#endif /* CONFIG_BRIDGE_NETFILTER */
+#else /* CONFIG_NETFILTER */
+static inline void nf_reset(struct sk_buff *skb) {}
+#endif /* CONFIG_NETFILTER */
+
+#endif /* __KERNEL__ */
+#endif /* _LINUX_SKBUFF_H */
--- /dev/null
+/*
+ * NET3 Protocol independent device support routines.
+ *
+ * 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.
+ *
+ * Derived from the non IP parts of dev.c 1.0.19
+ * Authors: Ross Biro, <bir7@leland.Stanford.Edu>
+ * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
+ * Mark Evans, <evansmp@uhura.aston.ac.uk>
+ *
+ * Additional Authors:
+ * Florian la Roche <rzsfl@rz.uni-sb.de>
+ * Alan Cox <gw4pts@gw4pts.ampr.org>
+ * David Hinds <dahinds@users.sourceforge.net>
+ * Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
+ * Adam Sulmicki <adam@cfar.umd.edu>
+ * Pekka Riikonen <priikone@poesidon.pspt.fi>
+ *
+ * Changes:
+ * D.J. Barrow : Fixed bug where dev->refcnt gets set
+ * to 2 if register_netdev gets called
+ * before net_dev_init & also removed a
+ * few lines of code in the process.
+ * Alan Cox : device private ioctl copies fields back.
+ * Alan Cox : Transmit queue code does relevant
+ * stunts to keep the queue safe.
+ * Alan Cox : Fixed double lock.
+ * Alan Cox : Fixed promisc NULL pointer trap
+ * ???????? : Support the full private ioctl range
+ * Alan Cox : Moved ioctl permission check into
+ * drivers
+ * Tim Kordas : SIOCADDMULTI/SIOCDELMULTI
+ * Alan Cox : 100 backlog just doesn't cut it when
+ * you start doing multicast video 8)
+ * Alan Cox : Rewrote net_bh and list manager.
+ * Alan Cox : Fix ETH_P_ALL echoback lengths.
+ * Alan Cox : Took out transmit every packet pass
+ * Saved a few bytes in the ioctl handler
+ * Alan Cox : Network driver sets packet type before
+ * calling netif_rx. Saves a function
+ * call a packet.
+ * Alan Cox : Hashed net_bh()
+ * Richard Kooijman: Timestamp fixes.
+ * Alan Cox : Wrong field in SIOCGIFDSTADDR
+ * Alan Cox : Device lock protection.
+ * Alan Cox : Fixed nasty side effect of device close
+ * changes.
+ * Rudi Cilibrasi : Pass the right thing to
+ * set_mac_address()
+ * Dave Miller : 32bit quantity for the device lock to
+ * make it work out on a Sparc.
+ * Bjorn Ekwall : Added KERNELD hack.
+ * Alan Cox : Cleaned up the backlog initialise.
+ * Craig Metz : SIOCGIFCONF fix if space for under
+ * 1 device.
+ * Thomas Bogendoerfer : Return ENODEV for dev_open, if there
+ * is no device open function.
+ * Andi Kleen : Fix error reporting for SIOCGIFCONF
+ * Michael Chastain : Fix signed/unsigned for SIOCGIFCONF
+ * Cyrus Durgin : Cleaned for KMOD
+ * Adam Sulmicki : Bug Fix : Network Device Unload
+ * A network device unload needs to purge
+ * the backlog queue.
+ * Paul Rusty Russell : SIOCSIFNAME
+ * Pekka Riikonen : Netdev boot-time settings code
+ * Andrew Morton : Make unregister_netdevice wait
+ * indefinitely on dev->refcnt
+ * J Hadi Salim : - Backlog queue sampling
+ * - netif_rx() feedback
+ */
+
+#include <asm/uaccess.h>
+#include <asm/system.h>
+#include <linux/bitops.h>
+#include <linux/config.h>
+#include <linux/cpu.h>
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/string.h>
+#include <linux/mm.h>
+#include <linux/socket.h>
+#include <linux/sockios.h>
+#include <linux/errno.h>
+#include <linux/interrupt.h>
+#include <linux/if_ether.h>
+#include <linux/netdevice.h>
+#include <linux/etherdevice.h>
+#include <linux/notifier.h>
+#include <linux/skbuff.h>
+#include <net/sock.h>
+#include <linux/rtnetlink.h>
+#include <linux/proc_fs.h>
+#include <linux/seq_file.h>
+#include <linux/stat.h>
+#include <linux/if_bridge.h>
+#include <linux/divert.h>
+#include <net/dst.h>
+#include <net/pkt_sched.h>
+#include <net/checksum.h>
+#include <linux/highmem.h>
+#include <linux/init.h>
+#include <linux/kmod.h>
+#include <linux/module.h>
+#include <linux/kallsyms.h>
+#include <linux/netpoll.h>
+#include <linux/rcupdate.h>
+#include <linux/delay.h>
+#ifdef CONFIG_NET_RADIO
+#include <linux/wireless.h> /* Note : will define WIRELESS_EXT */
+#include <net/iw_handler.h>
+#endif /* CONFIG_NET_RADIO */
+#include <asm/current.h>
+
+#include <net/ip.h>
+#include <linux/tcp.h>
+#include <linux/udp.h>
+
+
+/* This define, if set, will randomly drop a packet when congestion
+ * is more than moderate. It helps fairness in the multi-interface
+ * case when one of them is a hog, but it kills performance for the
+ * single interface case so it is off now by default.
+ */
+#undef RAND_LIE
+
+/* Setting this will sample the queue lengths and thus congestion
+ * via a timer instead of as each packet is received.
+ */
+#undef OFFLINE_SAMPLE
+
+/*
+ * The list of packet types we will receive (as opposed to discard)
+ * and the routines to invoke.
+ *
+ * Why 16. Because with 16 the only overlap we get on a hash of the
+ * low nibble of the protocol value is RARP/SNAP/X.25.
+ *
+ * NOTE: That is no longer true with the addition of VLAN tags. Not
+ * sure which should go first, but I bet it won't make much
+ * difference if we are running VLANs. The good news is that
+ * this protocol won't be in the list unless compiled in, so
+ * the average user (w/out VLANs) will not be adversly affected.
+ * --BLG
+ *
+ * 0800 IP
+ * 8100 802.1Q VLAN
+ * 0001 802.3
+ * 0002 AX.25
+ * 0004 802.2
+ * 8035 RARP
+ * 0005 SNAP
+ * 0805 X.25
+ * 0806 ARP
+ * 8137 IPX
+ * 0009 Localtalk
+ * 86DD IPv6
+ */
+
+static DEFINE_SPINLOCK(ptype_lock);
+static struct list_head ptype_base[16]; /* 16 way hashed list */
+static struct list_head ptype_all; /* Taps */
+
+#ifdef OFFLINE_SAMPLE
+static void sample_queue(unsigned long dummy);
+static struct timer_list samp_timer = TIMER_INITIALIZER(sample_queue, 0, 0);
+#endif
+
+/*
+ * The @dev_base list is protected by @dev_base_lock and the rtln
+ * semaphore.
+ *
+ * Pure readers hold dev_base_lock for reading.
+ *
+ * Writers must hold the rtnl semaphore while they loop through the
+ * dev_base list, and hold dev_base_lock for writing when they do the
+ * actual updates. This allows pure readers to access the list even
+ * while a writer is preparing to update it.
+ *
+ * To put it another way, dev_base_lock is held for writing only to
+ * protect against pure readers; the rtnl semaphore provides the
+ * protection against other writers.
+ *
+ * See, for example usages, register_netdevice() and
+ * unregister_netdevice(), which must be called with the rtnl
+ * semaphore held.
+ */
+struct net_device *dev_base;
+static struct net_device **dev_tail = &dev_base;
+DEFINE_RWLOCK(dev_base_lock);
+
+EXPORT_SYMBOL(dev_base);
+EXPORT_SYMBOL(dev_base_lock);
+
+#define NETDEV_HASHBITS 8
+static struct hlist_head dev_name_head[1<<NETDEV_HASHBITS];
+static struct hlist_head dev_index_head[1<<NETDEV_HASHBITS];
+
+static inline struct hlist_head *dev_name_hash(const char *name)
+{
+ unsigned hash = full_name_hash(name, strnlen(name, IFNAMSIZ));
+ return &dev_name_head[hash & ((1<<NETDEV_HASHBITS)-1)];
+}
+
+static inline struct hlist_head *dev_index_hash(int ifindex)
+{
+ return &dev_index_head[ifindex & ((1<<NETDEV_HASHBITS)-1)];
+}
+
+/*
+ * Our notifier list
+ */
+
+static struct notifier_block *netdev_chain;
+
+/*
+ * Device drivers call our routines to queue packets here. We empty the
+ * queue in the local softnet handler.
+ */
+DEFINE_PER_CPU(struct softnet_data, softnet_data) = { 0, };
+
+#ifdef CONFIG_SYSFS
+extern int netdev_sysfs_init(void);
+extern int netdev_register_sysfs(struct net_device *);
+extern void netdev_unregister_sysfs(struct net_device *);
+#else
+#define netdev_sysfs_init() (0)
+#define netdev_register_sysfs(dev) (0)
+#define netdev_unregister_sysfs(dev) do { } while(0)
+#endif
+
+
+/*******************************************************************************
+
+ Protocol management and registration routines
+
+*******************************************************************************/
+
+/*
+ * For efficiency
+ */
+
+int netdev_nit;
+
+/*
+ * Add a protocol ID to the list. Now that the input handler is
+ * smarter we can dispense with all the messy stuff that used to be
+ * here.
+ *
+ * BEWARE!!! Protocol handlers, mangling input packets,
+ * MUST BE last in hash buckets and checking protocol handlers
+ * MUST start from promiscuous ptype_all chain in net_bh.
+ * It is true now, do not change it.
+ * Explanation follows: if protocol handler, mangling packet, will
+ * be the first on list, it is not able to sense, that packet
+ * is cloned and should be copied-on-write, so that it will
+ * change it and subsequent readers will get broken packet.
+ * --ANK (980803)
+ */
+
+/**
+ * dev_add_pack - add packet handler
+ * @pt: packet type declaration
+ *
+ * Add a protocol handler to the networking stack. The passed &packet_type
+ * is linked into kernel lists and may not be freed until it has been
+ * removed from the kernel lists.
+ *
+ * This call does not sleep therefore it can not
+ * guarantee all CPU's that are in middle of receiving packets
+ * will see the new packet type (until the next received packet).
+ */
+
+void dev_add_pack(struct packet_type *pt)
+{
+ int hash;
+
+ spin_lock_bh(&ptype_lock);
+ if (pt->type == htons(ETH_P_ALL)) {
+ netdev_nit++;
+ list_add_rcu(&pt->list, &ptype_all);
+ } else {
+ hash = ntohs(pt->type) & 15;
+ list_add_rcu(&pt->list, &ptype_base[hash]);
+ }
+ spin_unlock_bh(&ptype_lock);
+}
+
+extern void linkwatch_run_queue(void);
+
+
+
+/**
+ * __dev_remove_pack - remove packet handler
+ * @pt: packet type declaration
+ *
+ * Remove a protocol handler that was previously added to the kernel
+ * protocol handlers by dev_add_pack(). The passed &packet_type is removed
+ * from the kernel lists and can be freed or reused once this function
+ * returns.
+ *
+ * The packet type might still be in use by receivers
+ * and must not be freed until after all the CPU's have gone
+ * through a quiescent state.
+ */
+void __dev_remove_pack(struct packet_type *pt)
+{
+ struct list_head *head;
+ struct packet_type *pt1;
+
+ spin_lock_bh(&ptype_lock);
+
+ if (pt->type == htons(ETH_P_ALL)) {
+ netdev_nit--;
+ head = &ptype_all;
+ } else
+ head = &ptype_base[ntohs(pt->type) & 15];
+
+ list_for_each_entry(pt1, head, list) {
+ if (pt == pt1) {
+ list_del_rcu(&pt->list);
+ goto out;
+ }
+ }
+
+ printk(KERN_WARNING "dev_remove_pack: %p not found.\n", pt);
+out:
+ spin_unlock_bh(&ptype_lock);
+}
+/**
+ * dev_remove_pack - remove packet handler
+ * @pt: packet type declaration
+ *
+ * Remove a protocol handler that was previously added to the kernel
+ * protocol handlers by dev_add_pack(). The passed &packet_type is removed
+ * from the kernel lists and can be freed or reused once this function
+ * returns.
+ *
+ * This call sleeps to guarantee that no CPU is looking at the packet
+ * type after return.
+ */
+void dev_remove_pack(struct packet_type *pt)
+{
+ __dev_remove_pack(pt);
+
+ synchronize_net();
+}
+
+/******************************************************************************
+
+ Device Boot-time Settings Routines
+
+*******************************************************************************/
+
+/* Boot time configuration table */
+static struct netdev_boot_setup dev_boot_setup[NETDEV_BOOT_SETUP_MAX];
+
+/**
+ * netdev_boot_setup_add - add new setup entry
+ * @name: name of the device
+ * @map: configured settings for the device
+ *
+ * Adds new setup entry to the dev_boot_setup list. The function
+ * returns 0 on error and 1 on success. This is a generic routine to
+ * all netdevices.
+ */
+static int netdev_boot_setup_add(char *name, struct ifmap *map)
+{
+ struct netdev_boot_setup *s;
+ int i;
+
+ s = dev_boot_setup;
+ for (i = 0; i < NETDEV_BOOT_SETUP_MAX; i++) {
+ if (s[i].name[0] == '\0' || s[i].name[0] == ' ') {
+ memset(s[i].name, 0, sizeof(s[i].name));
+ strcpy(s[i].name, name);
+ memcpy(&s[i].map, map, sizeof(s[i].map));
+ break;
+ }
+ }
+
+ return i >= NETDEV_BOOT_SETUP_MAX ? 0 : 1;
+}
+
+/**
+ * netdev_boot_setup_check - check boot time settings
+ * @dev: the netdevice
+ *
+ * Check boot time settings for the device.
+ * The found settings are set for the device to be used
+ * later in the device probing.
+ * Returns 0 if no settings found, 1 if they are.
+ */
+int netdev_boot_setup_check(struct net_device *dev)
+{
+ struct netdev_boot_setup *s = dev_boot_setup;
+ int i;
+
+ for (i = 0; i < NETDEV_BOOT_SETUP_MAX; i++) {
+ if (s[i].name[0] != '\0' && s[i].name[0] != ' ' &&
+ !strncmp(dev->name, s[i].name, strlen(s[i].name))) {
+ dev->irq = s[i].map.irq;
+ dev->base_addr = s[i].map.base_addr;
+ dev->mem_start = s[i].map.mem_start;
+ dev->mem_end = s[i].map.mem_end;
+ return 1;
+ }
+ }
+ return 0;
+}
+
+
+/**
+ * netdev_boot_base - get address from boot time settings
+ * @prefix: prefix for network device
+ * @unit: id for network device
+ *
+ * Check boot time settings for the base address of device.
+ * The found settings are set for the device to be used
+ * later in the device probing.
+ * Returns 0 if no settings found.
+ */
+unsigned long netdev_boot_base(const char *prefix, int unit)
+{
+ const struct netdev_boot_setup *s = dev_boot_setup;
+ char name[IFNAMSIZ];
+ int i;
+
+ sprintf(name, "%s%d", prefix, unit);
+
+ /*
+ * If device already registered then return base of 1
+ * to indicate not to probe for this interface
+ */
+ if (__dev_get_by_name(name))
+ return 1;
+
+ for (i = 0; i < NETDEV_BOOT_SETUP_MAX; i++)
+ if (!strcmp(name, s[i].name))
+ return s[i].map.base_addr;
+ return 0;
+}
+
+/*
+ * Saves at boot time configured settings for any netdevice.
+ */
+int __init netdev_boot_setup(char *str)
+{
+ int ints[5];
+ struct ifmap map;
+
+ str = get_options(str, ARRAY_SIZE(ints), ints);
+ if (!str || !*str)
+ return 0;
+
+ /* Save settings */
+ memset(&map, 0, sizeof(map));
+ if (ints[0] > 0)
+ map.irq = ints[1];
+ if (ints[0] > 1)
+ map.base_addr = ints[2];
+ if (ints[0] > 2)
+ map.mem_start = ints[3];
+ if (ints[0] > 3)
+ map.mem_end = ints[4];
+
+ /* Add new entry to the list */
+ return netdev_boot_setup_add(str, &map);
+}
+
+__setup("netdev=", netdev_boot_setup);
+
+/*******************************************************************************
+
+ Device Interface Subroutines
+
+*******************************************************************************/
+
+/**
+ * __dev_get_by_name - find a device by its name
+ * @name: name to find
+ *
+ * Find an interface by name. Must be called under RTNL semaphore
+ * or @dev_base_lock. If the name is found a pointer to the device
+ * is returned. If the name is not found then %NULL is returned. The
+ * reference counters are not incremented so the caller must be
+ * careful with locks.
+ */
+
+struct net_device *__dev_get_by_name(const char *name)
+{
+ struct hlist_node *p;
+
+ hlist_for_each(p, dev_name_hash(name)) {
+ struct net_device *dev
+ = hlist_entry(p, struct net_device, name_hlist);
+ if (!strncmp(dev->name, name, IFNAMSIZ))
+ return dev;
+ }
+ return NULL;
+}
+
+/**
+ * dev_get_by_name - find a device by its name
+ * @name: name to find
+ *
+ * Find an interface by name. This can be called from any
+ * context and does its own locking. The returned handle has
+ * the usage count incremented and the caller must use dev_put() to
+ * release it when it is no longer needed. %NULL is returned if no
+ * matching device is found.
+ */
+
+struct net_device *dev_get_by_name(const char *name)
+{
+ struct net_device *dev;
+
+ read_lock(&dev_base_lock);
+ dev = __dev_get_by_name(name);
+ if (dev)
+ dev_hold(dev);
+ read_unlock(&dev_base_lock);
+ return dev;
+}
+
+/**
+ * __dev_get_by_index - find a device by its ifindex
+ * @ifindex: index of device
+ *
+ * Search for an interface by index. Returns %NULL if the device
+ * is not found or a pointer to the device. The device has not
+ * had its reference counter increased so the caller must be careful
+ * about locking. The caller must hold either the RTNL semaphore
+ * or @dev_base_lock.
+ */
+
+struct net_device *__dev_get_by_index(int ifindex)
+{
+ struct hlist_node *p;
+
+ hlist_for_each(p, dev_index_hash(ifindex)) {
+ struct net_device *dev
+ = hlist_entry(p, struct net_device, index_hlist);
+ if (dev->ifindex == ifindex)
+ return dev;
+ }
+ return NULL;
+}
+
+
+/**
+ * dev_get_by_index - find a device by its ifindex
+ * @ifindex: index of device
+ *
+ * Search for an interface by index. Returns NULL if the device
+ * is not found or a pointer to the device. The device returned has
+ * had a reference added and the pointer is safe until the user calls
+ * dev_put to indicate they have finished with it.
+ */
+
+struct net_device *dev_get_by_index(int ifindex)
+{
+ struct net_device *dev;
+
+ read_lock(&dev_base_lock);
+ dev = __dev_get_by_index(ifindex);
+ if (dev)
+ dev_hold(dev);
+ read_unlock(&dev_base_lock);
+ return dev;
+}
+
+/**
+ * dev_getbyhwaddr - find a device by its hardware address
+ * @type: media type of device
+ * @ha: hardware address
+ *
+ * Search for an interface by MAC address. Returns NULL if the device
+ * is not found or a pointer to the device. The caller must hold the
+ * rtnl semaphore. The returned device has not had its ref count increased
+ * and the caller must therefore be careful about locking
+ *
+ * BUGS:
+ * If the API was consistent this would be __dev_get_by_hwaddr
+ */
+
+struct net_device *dev_getbyhwaddr(unsigned short type, char *ha)
+{
+ struct net_device *dev;
+
+ ASSERT_RTNL();
+
+ for (dev = dev_base; dev; dev = dev->next)
+ if (dev->type == type &&
+ !memcmp(dev->dev_addr, ha, dev->addr_len))
+ break;
+ return dev;
+}
+
+struct net_device *dev_getfirstbyhwtype(unsigned short type)
+{
+ struct net_device *dev;
+
+ rtnl_lock();
+ for (dev = dev_base; dev; dev = dev->next) {
+ if (dev->type == type) {
+ dev_hold(dev);
+ break;
+ }
+ }
+ rtnl_unlock();
+ return dev;
+}
+
+EXPORT_SYMBOL(dev_getfirstbyhwtype);
+
+/**
+ * dev_get_by_flags - find any device with given flags
+ * @if_flags: IFF_* values
+ * @mask: bitmask of bits in if_flags to check
+ *
+ * Search for any interface with the given flags. Returns NULL if a device
+ * is not found or a pointer to the device. The device returned has
+ * had a reference added and the pointer is safe until the user calls
+ * dev_put to indicate they have finished with it.
+ */
+
+struct net_device * dev_get_by_flags(unsigned short if_flags, unsigned short mask)
+{
+ struct net_device *dev;
+
+ read_lock(&dev_base_lock);
+ for (dev = dev_base; dev != NULL; dev = dev->next) {
+ if (((dev->flags ^ if_flags) & mask) == 0) {
+ dev_hold(dev);
+ break;
+ }
+ }
+ read_unlock(&dev_base_lock);
+ return dev;
+}
+
+/**
+ * dev_valid_name - check if name is okay for network device
+ * @name: name string
+ *
+ * Network device names need to be valid file names to
+ * to allow sysfs to work
+ */
+static int dev_valid_name(const char *name)
+{
+ return !(*name == '\0'
+ || !strcmp(name, ".")
+ || !strcmp(name, "..")
+ || strchr(name, '/'));
+}
+
+/**
+ * dev_alloc_name - allocate a name for a device
+ * @dev: device
+ * @name: name format string
+ *
+ * Passed a format string - eg "lt%d" it will try and find a suitable
+ * id. Not efficient for many devices, not called a lot. The caller
+ * must hold the dev_base or rtnl lock while allocating the name and
+ * adding the device in order to avoid duplicates. Returns the number
+ * of the unit assigned or a negative errno code.
+ */
+
+int dev_alloc_name(struct net_device *dev, const char *name)
+{
+ int i = 0;
+ char buf[IFNAMSIZ];
+ const char *p;
+ const int max_netdevices = 8*PAGE_SIZE;
+ long *inuse;
+ struct net_device *d;
+
+ p = strnchr(name, IFNAMSIZ-1, '%');
+ if (p) {
+ /*
+ * Verify the string as this thing may have come from
+ * the user. There must be either one "%d" and no other "%"
+ * characters.
+ */
+ if (p[1] != 'd' || strchr(p + 2, '%'))
+ return -EINVAL;
+
+ /* Use one page as a bit array of possible slots */
+ inuse = (long *) get_zeroed_page(GFP_ATOMIC);
+ if (!inuse)
+ return -ENOMEM;
+
+ for (d = dev_base; d; d = d->next) {
+ if (!sscanf(d->name, name, &i))
+ continue;
+ if (i < 0 || i >= max_netdevices)
+ continue;
+
+ /* avoid cases where sscanf is not exact inverse of printf */
+ snprintf(buf, sizeof(buf), name, i);
+ if (!strncmp(buf, d->name, IFNAMSIZ))
+ set_bit(i, inuse);
+ }
+
+ i = find_first_zero_bit(inuse, max_netdevices);
+ free_page((unsigned long) inuse);
+ }
+
+ snprintf(buf, sizeof(buf), name, i);
+ if (!__dev_get_by_name(buf)) {
+ strlcpy(dev->name, buf, IFNAMSIZ);
+ return i;
+ }
+
+ /* It is possible to run out of possible slots
+ * when the name is long and there isn't enough space left
+ * for the digits, or if all bits are used.
+ */
+ return -ENFILE;
+}
+
+
+/**
+ * dev_change_name - change name of a device
+ * @dev: device
+ * @newname: name (or format string) must be at least IFNAMSIZ
+ *
+ * Change name of a device, can pass format strings "eth%d".
+ * for wildcarding.
+ */
+int dev_change_name(struct net_device *dev, char *newname)
+{
+ int err = 0;
+
+ ASSERT_RTNL();
+
+ if (dev->flags & IFF_UP)
+ return -EBUSY;
+
+ if (!dev_valid_name(newname))
+ return -EINVAL;
+
+ if (strchr(newname, '%')) {
+ err = dev_alloc_name(dev, newname);
+ if (err < 0)
+ return err;
+ strcpy(newname, dev->name);
+ }
+ else if (__dev_get_by_name(newname))
+ return -EEXIST;
+ else
+ strlcpy(dev->name, newname, IFNAMSIZ);
+
+ err = class_device_rename(&dev->class_dev, dev->name);
+ if (!err) {
+ hlist_del(&dev->name_hlist);
+ hlist_add_head(&dev->name_hlist, dev_name_hash(dev->name));
+ notifier_call_chain(&netdev_chain, NETDEV_CHANGENAME, dev);
+ }
+
+ return err;
+}
+
+/**
+ * netdev_state_change - device changes state
+ * @dev: device to cause notification
+ *
+ * Called to indicate a device has changed state. This function calls
+ * the notifier chains for netdev_chain and sends a NEWLINK message
+ * to the routing socket.
+ */
+void netdev_state_change(struct net_device *dev)
+{
+ if (dev->flags & IFF_UP) {
+ notifier_call_chain(&netdev_chain, NETDEV_CHANGE, dev);
+ rtmsg_ifinfo(RTM_NEWLINK, dev, 0);
+ }
+}
+
+/**
+ * dev_load - load a network module
+ * @name: name of interface
+ *
+ * If a network interface is not present and the process has suitable
+ * privileges this function loads the module. If module loading is not
+ * available in this kernel then it becomes a nop.
+ */
+
+void dev_load(const char *name)
+{
+ struct net_device *dev;
+
+ read_lock(&dev_base_lock);
+ dev = __dev_get_by_name(name);
+ read_unlock(&dev_base_lock);
+
+ if (!dev && capable(CAP_SYS_MODULE))
+ request_module("%s", name);
+}
+
+static int default_rebuild_header(struct sk_buff *skb)
+{
+ printk(KERN_DEBUG "%s: default_rebuild_header called -- BUG!\n",
+ skb->dev ? skb->dev->name : "NULL!!!");
+ kfree_skb(skb);
+ return 1;
+}
+
+
+/**
+ * dev_open - prepare an interface for use.
+ * @dev: device to open
+ *
+ * Takes a device from down to up state. The device's private open
+ * function is invoked and then the multicast lists are loaded. Finally
+ * the device is moved into the up state and a %NETDEV_UP message is
+ * sent to the netdev notifier chain.
+ *
+ * Calling this function on an active interface is a nop. On a failure
+ * a negative errno code is returned.
+ */
+int dev_open(struct net_device *dev)
+{
+ int ret = 0;
+
+ /*
+ * Is it already up?
+ */
+
+ if (dev->flags & IFF_UP)
+ return 0;
+
+ /*
+ * Is it even present?
+ */
+ if (!netif_device_present(dev))
+ return -ENODEV;
+
+ /*
+ * Call device private open method
+ */
+ set_bit(__LINK_STATE_START, &dev->state);
+ if (dev->open) {
+ ret = dev->open(dev);
+ if (ret)
+ clear_bit(__LINK_STATE_START, &dev->state);
+ }
+
+ /*
+ * If it went open OK then:
+ */
+
+ if (!ret) {
+ /*
+ * Set the flags.
+ */
+ dev->flags |= IFF_UP;
+
+ /*
+ * Initialize multicasting status
+ */
+ dev_mc_upload(dev);
+
+ /*
+ * Wakeup transmit queue engine
+ */
+ dev_activate(dev);
+
+ /*
+ * ... and announce new interface.
+ */
+ notifier_call_chain(&netdev_chain, NETDEV_UP, dev);
+ }
+ return ret;
+}
+
+/**
+ * dev_close - shutdown an interface.
+ * @dev: device to shutdown
+ *
+ * This function moves an active device into down state. A
+ * %NETDEV_GOING_DOWN is sent to the netdev notifier chain. The device
+ * is then deactivated and finally a %NETDEV_DOWN is sent to the notifier
+ * chain.
+ */
+int dev_close(struct net_device *dev)
+{
+ if (!(dev->flags & IFF_UP))
+ return 0;
+
+ /*
+ * Tell people we are going down, so that they can
+ * prepare to death, when device is still operating.
+ */
+ notifier_call_chain(&netdev_chain, NETDEV_GOING_DOWN, dev);
+
+ dev_deactivate(dev);
+
+ clear_bit(__LINK_STATE_START, &dev->state);
+
+ /* Synchronize to scheduled poll. We cannot touch poll list,
+ * it can be even on different cpu. So just clear netif_running(),
+ * and wait when poll really will happen. Actually, the best place
+ * for this is inside dev->stop() after device stopped its irq
+ * engine, but this requires more changes in devices. */
+
+ smp_mb__after_clear_bit(); /* Commit netif_running(). */
+ while (test_bit(__LINK_STATE_RX_SCHED, &dev->state)) {
+ /* No hurry. */
+ current->state = TASK_INTERRUPTIBLE;
+ schedule_timeout(1);
+ }
+
+ /*
+ * Call the device specific close. This cannot fail.
+ * Only if device is UP
+ *
+ * We allow it to be called even after a DETACH hot-plug
+ * event.
+ */
+ if (dev->stop)
+ dev->stop(dev);
+
+ /*
+ * Device is now down.
+ */
+
+ dev->flags &= ~IFF_UP;
+
+ /*
+ * Tell people we are down
+ */
+ notifier_call_chain(&netdev_chain, NETDEV_DOWN, dev);
+
+ return 0;
+}
+
+
+/*
+ * Device change register/unregister. These are not inline or static
+ * as we export them to the world.
+ */
+
+/**
+ * register_netdevice_notifier - register a network notifier block
+ * @nb: notifier
+ *
+ * Register a notifier to be called when network device events occur.
+ * The notifier passed is linked into the kernel structures and must
+ * not be reused until it has been unregistered. A negative errno code
+ * is returned on a failure.
+ *
+ * When registered all registration and up events are replayed
+ * to the new notifier to allow device to have a race free
+ * view of the network device list.
+ */
+
+int register_netdevice_notifier(struct notifier_block *nb)
+{
+ struct net_device *dev;
+ int err;
+
+ rtnl_lock();
+ err = notifier_chain_register(&netdev_chain, nb);
+ if (!err) {
+ for (dev = dev_base; dev; dev = dev->next) {
+ nb->notifier_call(nb, NETDEV_REGISTER, dev);
+
+ if (dev->flags & IFF_UP)
+ nb->notifier_call(nb, NETDEV_UP, dev);
+ }
+ }
+ rtnl_unlock();
+ return err;
+}
+
+/**
+ * unregister_netdevice_notifier - unregister a network notifier block
+ * @nb: notifier
+ *
+ * Unregister a notifier previously registered by
+ * register_netdevice_notifier(). The notifier is unlinked into the
+ * kernel structures and may then be reused. A negative errno code
+ * is returned on a failure.
+ */
+
+int unregister_netdevice_notifier(struct notifier_block *nb)
+{
+ return notifier_chain_unregister(&netdev_chain, nb);
+}
+
+/**
+ * call_netdevice_notifiers - call all network notifier blocks
+ * @val: value passed unmodified to notifier function
+ * @v: pointer passed unmodified to notifier function
+ *
+ * Call all network notifier blocks. Parameters and return value
+ * are as for notifier_call_chain().
+ */
+
+int call_netdevice_notifiers(unsigned long val, void *v)
+{
+ return notifier_call_chain(&netdev_chain, val, v);
+}
+
+/* When > 0 there are consumers of rx skb time stamps */
+static atomic_t netstamp_needed = ATOMIC_INIT(0);
+
+void net_enable_timestamp(void)
+{
+ atomic_inc(&netstamp_needed);
+}
+
+void net_disable_timestamp(void)
+{
+ atomic_dec(&netstamp_needed);
+}
+
+static inline void net_timestamp(struct timeval *stamp)
+{
+ if (atomic_read(&netstamp_needed))
+ do_gettimeofday(stamp);
+ else {
+ stamp->tv_sec = 0;
+ stamp->tv_usec = 0;
+ }
+}
+
+/*
+ * Support routine. Sends outgoing frames to any network
+ * taps currently in use.
+ */
+
+void dev_queue_xmit_nit(struct sk_buff *skb, struct net_device *dev)
+{
+ struct packet_type *ptype;
+ net_timestamp(&skb->stamp);
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(ptype, &ptype_all, list) {
+ /* Never send packets back to the socket
+ * they originated from - MvS (miquels@drinkel.ow.org)
+ */
+ if ((ptype->dev == dev || !ptype->dev) &&
+ (ptype->af_packet_priv == NULL ||
+ (struct sock *)ptype->af_packet_priv != skb->sk)) {
+ struct sk_buff *skb2= skb_clone(skb, GFP_ATOMIC);
+ if (!skb2)
+ break;
+
+ /* skb->nh should be correctly
+ set by sender, so that the second statement is
+ just protection against buggy protocols.
+ */
+ skb2->mac.raw = skb2->data;
+
+ if (skb2->nh.raw < skb2->data ||
+ skb2->nh.raw > skb2->tail) {
+ if (net_ratelimit())
+ printk(KERN_CRIT "protocol %04x is "
+ "buggy, dev %s\n",
+ skb2->protocol, dev->name);
+ skb2->nh.raw = skb2->data;
+ }
+
+ skb2->h.raw = skb2->nh.raw;
+ skb2->pkt_type = PACKET_OUTGOING;
+ ptype->func(skb2, skb->dev, ptype);
+ }
+ }
+ rcu_read_unlock();
+}
+
+/*
+ * Invalidate hardware checksum when packet is to be mangled, and
+ * complete checksum manually on outgoing path.
+ */
+int skb_checksum_help(struct sk_buff *skb, int inward)
+{
+ unsigned int csum;
+ int ret = 0, offset = skb->h.raw - skb->data;
+
+ if (inward) {
+ skb->ip_summed = CHECKSUM_NONE;
+ goto out;
+ }
+
+ if (skb_cloned(skb)) {
+ ret = pskb_expand_head(skb, 0, 0, GFP_ATOMIC);
+ if (ret)
+ goto out;
+ }
+
+ if (offset > (int)skb->len)
+ BUG();
+ csum = skb_checksum(skb, offset, skb->len-offset, 0);
+
+ offset = skb->tail - skb->h.raw;
+ if (offset <= 0)
+ BUG();
+ if (skb->csum + 2 > offset)
+ BUG();
+
+ *(u16*)(skb->h.raw + skb->csum) = csum_fold(csum);
+ skb->ip_summed = CHECKSUM_NONE;
+out:
+ return ret;
+}
+
+#ifdef CONFIG_HIGHMEM
+/* Actually, we should eliminate this check as soon as we know, that:
+ * 1. IOMMU is present and allows to map all the memory.
+ * 2. No high memory really exists on this machine.
+ */
+
+static inline int illegal_highdma(struct net_device *dev, struct sk_buff *skb)
+{
+ int i;
+
+ if (dev->features & NETIF_F_HIGHDMA)
+ return 0;
+
+ for (i = 0; i < skb_shinfo(skb)->nr_frags; i++)
+ if (PageHighMem(skb_shinfo(skb)->frags[i].page))
+ return 1;
+
+ return 0;
+}
+#else
+#define illegal_highdma(dev, skb) (0)
+#endif
+
+extern void skb_release_data(struct sk_buff *);
+
+/* Keep head the same: replace data */
+int __skb_linearize(struct sk_buff *skb, int gfp_mask)
+{
+ unsigned int size;
+ u8 *data;
+ long offset;
+ struct skb_shared_info *ninfo;
+ 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)
+ return -ENOMEM;
+
+ /* Copy entire thing */
+ if (skb_copy_bits(skb, -headerlen, data, headerlen + skb->len))
+ BUG();
+
+ /* Set up shinfo */
+ ninfo = (struct skb_shared_info*)(data + size);
+ atomic_set(&ninfo->dataref, 1);
+ ninfo->tso_size = skb_shinfo(skb)->tso_size;
+ ninfo->tso_segs = skb_shinfo(skb)->tso_segs;
+ ninfo->nr_frags = 0;
+ ninfo->frag_list = NULL;
+
+ /* 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;
+
+ /* We are no longer a clone, even if we were. */
+ skb->cloned = 0;
+
+ skb->tail += skb->data_len;
+ skb->data_len = 0;
+ return 0;
+}
+
+#define HARD_TX_LOCK(dev, cpu) { \
+ if ((dev->features & NETIF_F_LLTX) == 0) { \
+ spin_lock(&dev->xmit_lock); \
+ dev->xmit_lock_owner = cpu; \
+ } \
+}
+
+#define HARD_TX_UNLOCK(dev) { \
+ if ((dev->features & NETIF_F_LLTX) == 0) { \
+ dev->xmit_lock_owner = -1; \
+ spin_unlock(&dev->xmit_lock); \
+ } \
+}
+
+/**
+ * dev_queue_xmit - transmit a buffer
+ * @skb: buffer to transmit
+ *
+ * Queue a buffer for transmission to a network device. The caller must
+ * have set the device and priority and built the buffer before calling
+ * this function. The function can be called from an interrupt.
+ *
+ * A negative errno code is returned on a failure. A success does not
+ * guarantee the frame will be transmitted as it may be dropped due
+ * to congestion or traffic shaping.
+ */
+
+int dev_queue_xmit(struct sk_buff *skb)
+{
+ struct net_device *dev = skb->dev;
+ struct Qdisc *q;
+ int rc = -ENOMEM;
+
+ if (skb_shinfo(skb)->frag_list &&
+ !(dev->features & NETIF_F_FRAGLIST) &&
+ __skb_linearize(skb, GFP_ATOMIC))
+ goto out_kfree_skb;
+
+ /* Fragmented skb is linearized if device does not support SG,
+ * or if at least one of fragments is in highmem and device
+ * does not support DMA from it.
+ */
+ if (skb_shinfo(skb)->nr_frags &&
+ (!(dev->features & NETIF_F_SG) || illegal_highdma(dev, skb)) &&
+ __skb_linearize(skb, GFP_ATOMIC))
+ goto out_kfree_skb;
+
+ /* If a checksum-deferred packet is forwarded to a device that needs a
+ * checksum, correct the pointers and force checksumming.
+ */
+ if (skb->proto_csum_blank) {
+ if (skb->protocol != htons(ETH_P_IP))
+ goto out_kfree_skb;
+ skb->h.raw = (unsigned char *)skb->nh.iph + 4*skb->nh.iph->ihl;
+ if (skb->h.raw >= skb->tail)
+ goto out_kfree_skb;
+ switch (skb->nh.iph->protocol) {
+ case IPPROTO_TCP:
+ skb->csum = offsetof(struct tcphdr, check);
+ break;
+ case IPPROTO_UDP:
+ skb->csum = offsetof(struct udphdr, check);
+ break;
+ default:
+ goto out_kfree_skb;
+ }
+ if ((skb->h.raw + skb->csum + 2) > skb->tail)
+ goto out_kfree_skb;
+ skb->ip_summed = CHECKSUM_HW;
+ }
+
+ /* If packet is not checksummed and device does not support
+ * checksumming for this protocol, complete checksumming here.
+ */
+ if (skb->ip_summed == CHECKSUM_HW &&
+ (!(dev->features & (NETIF_F_HW_CSUM | NETIF_F_NO_CSUM)) &&
+ (!(dev->features & NETIF_F_IP_CSUM) ||
+ skb->protocol != htons(ETH_P_IP))))
+ if (skb_checksum_help(skb, 0))
+ goto out_kfree_skb;
+
+ /* Disable soft irqs for various locks below. Also
+ * stops preemption for RCU.
+ */
+ local_bh_disable();
+
+ /* Updates of qdisc are serialized by queue_lock.
+ * The struct Qdisc which is pointed to by qdisc is now a
+ * rcu structure - it may be accessed without acquiring
+ * a lock (but the structure may be stale.) The freeing of the
+ * qdisc will be deferred until it's known that there are no
+ * more references to it.
+ *
+ * If the qdisc has an enqueue function, we still need to
+ * hold the queue_lock before calling it, since queue_lock
+ * also serializes access to the device queue.
+ */
+
+ q = rcu_dereference(dev->qdisc);
+#ifdef CONFIG_NET_CLS_ACT
+ skb->tc_verd = SET_TC_AT(skb->tc_verd,AT_EGRESS);
+#endif
+ if (q->enqueue) {
+ /* Grab device queue */
+ spin_lock(&dev->queue_lock);
+
+ rc = q->enqueue(skb, q);
+
+ qdisc_run(dev);
+
+ spin_unlock(&dev->queue_lock);
+ rc = rc == NET_XMIT_BYPASS ? NET_XMIT_SUCCESS : rc;
+ goto out;
+ }
+
+ /* The device has no queue. Common case for software devices:
+ loopback, all the sorts of tunnels...
+
+ Really, it is unlikely that xmit_lock protection is necessary here.
+ (f.e. loopback and IP tunnels are clean ignoring statistics
+ counters.)
+ However, it is possible, that they rely on protection
+ made by us here.
+
+ Check this and shot the lock. It is not prone from deadlocks.
+ Either shot noqueue qdisc, it is even simpler 8)
+ */
+ if (dev->flags & IFF_UP) {
+ int cpu = smp_processor_id(); /* ok because BHs are off */
+
+ if (dev->xmit_lock_owner != cpu) {
+
+ HARD_TX_LOCK(dev, cpu);
+
+ if (!netif_queue_stopped(dev)) {
+ if (netdev_nit)
+ dev_queue_xmit_nit(skb, dev);
+
+ rc = 0;
+ if (!dev->hard_start_xmit(skb, dev)) {
+ HARD_TX_UNLOCK(dev);
+ goto out;
+ }
+ }
+ HARD_TX_UNLOCK(dev);
+ if (net_ratelimit())
+ printk(KERN_CRIT "Virtual device %s asks to "
+ "queue packet!\n", dev->name);
+ } else {
+ /* Recursion is detected! It is possible,
+ * unfortunately */
+ if (net_ratelimit())
+ printk(KERN_CRIT "Dead loop on virtual device "
+ "%s, fix it urgently!\n", dev->name);
+ }
+ }
+
+ rc = -ENETDOWN;
+ local_bh_enable();
+
+out_kfree_skb:
+ kfree_skb(skb);
+ return rc;
+out:
+ local_bh_enable();
+ return rc;
+}
+
+
+/*=======================================================================
+ Receiver routines
+ =======================================================================*/
+
+int netdev_max_backlog = 300;
+int weight_p = 64; /* old backlog weight */
+/* These numbers are selected based on intuition and some
+ * experimentatiom, if you have more scientific way of doing this
+ * please go ahead and fix things.
+ */
+int no_cong_thresh = 10;
+int no_cong = 20;
+int lo_cong = 100;
+int mod_cong = 290;
+
+DEFINE_PER_CPU(struct netif_rx_stats, netdev_rx_stat) = { 0, };
+
+
+static void get_sample_stats(int cpu)
+{
+#ifdef RAND_LIE
+ unsigned long rd;
+ int rq;
+#endif
+ struct softnet_data *sd = &per_cpu(softnet_data, cpu);
+ int blog = sd->input_pkt_queue.qlen;
+ int avg_blog = sd->avg_blog;
+
+ avg_blog = (avg_blog >> 1) + (blog >> 1);
+
+ if (avg_blog > mod_cong) {
+ /* Above moderate congestion levels. */
+ sd->cng_level = NET_RX_CN_HIGH;
+#ifdef RAND_LIE
+ rd = net_random();
+ rq = rd % netdev_max_backlog;
+ if (rq < avg_blog) /* unlucky bastard */
+ sd->cng_level = NET_RX_DROP;
+#endif
+ } else if (avg_blog > lo_cong) {
+ sd->cng_level = NET_RX_CN_MOD;
+#ifdef RAND_LIE
+ rd = net_random();
+ rq = rd % netdev_max_backlog;
+ if (rq < avg_blog) /* unlucky bastard */
+ sd->cng_level = NET_RX_CN_HIGH;
+#endif
+ } else if (avg_blog > no_cong)
+ sd->cng_level = NET_RX_CN_LOW;
+ else /* no congestion */
+ sd->cng_level = NET_RX_SUCCESS;
+
+ sd->avg_blog = avg_blog;
+}
+
+#ifdef OFFLINE_SAMPLE
+static void sample_queue(unsigned long dummy)
+{
+/* 10 ms 0r 1ms -- i don't care -- JHS */
+ int next_tick = 1;
+ int cpu = smp_processor_id();
+
+ get_sample_stats(cpu);
+ next_tick += jiffies;
+ mod_timer(&samp_timer, next_tick);
+}
+#endif
+
+
+/**
+ * netif_rx - post buffer to the network code
+ * @skb: buffer to post
+ *
+ * This function receives a packet from a device driver and queues it for
+ * the upper (protocol) levels to process. It always succeeds. The buffer
+ * may be dropped during processing for congestion control or by the
+ * protocol layers.
+ *
+ * return values:
+ * NET_RX_SUCCESS (no congestion)
+ * NET_RX_CN_LOW (low congestion)
+ * NET_RX_CN_MOD (moderate congestion)
+ * NET_RX_CN_HIGH (high congestion)
+ * NET_RX_DROP (packet was dropped)
+ *
+ */
+
+int netif_rx(struct sk_buff *skb)
+{
+ int this_cpu;
+ struct softnet_data *queue;
+ unsigned long flags;
+
+#ifdef CONFIG_NETPOLL
+ if (skb->dev->netpoll_rx && netpoll_rx(skb)) {
+ kfree_skb(skb);
+ return NET_RX_DROP;
+ }
+#endif
+
+ if (!skb->stamp.tv_sec)
+ net_timestamp(&skb->stamp);
+
+ /*
+ * The code is rearranged so that the path is the most
+ * short when CPU is congested, but is still operating.
+ */
+ local_irq_save(flags);
+ this_cpu = smp_processor_id();
+ queue = &__get_cpu_var(softnet_data);
+
+ __get_cpu_var(netdev_rx_stat).total++;
+ if (queue->input_pkt_queue.qlen <= netdev_max_backlog) {
+ if (queue->input_pkt_queue.qlen) {
+ if (queue->throttle)
+ goto drop;
+
+enqueue:
+ dev_hold(skb->dev);
+ __skb_queue_tail(&queue->input_pkt_queue, skb);
+#ifndef OFFLINE_SAMPLE
+ get_sample_stats(this_cpu);
+#endif
+ local_irq_restore(flags);
+ return queue->cng_level;
+ }
+
+ if (queue->throttle)
+ queue->throttle = 0;
+
+ netif_rx_schedule(&queue->backlog_dev);
+ goto enqueue;
+ }
+
+ if (!queue->throttle) {
+ queue->throttle = 1;
+ __get_cpu_var(netdev_rx_stat).throttled++;
+ }
+
+drop:
+ __get_cpu_var(netdev_rx_stat).dropped++;
+ local_irq_restore(flags);
+
+ kfree_skb(skb);
+ return NET_RX_DROP;
+}
+
+int netif_rx_ni(struct sk_buff *skb)
+{
+ int err;
+
+ preempt_disable();
+ err = netif_rx(skb);
+ if (local_softirq_pending())
+ do_softirq();
+ preempt_enable();
+
+ return err;
+}
+
+EXPORT_SYMBOL(netif_rx_ni);
+
+static __inline__ void skb_bond(struct sk_buff *skb)
+{
+ struct net_device *dev = skb->dev;
+
+ if (dev->master) {
+ skb->real_dev = skb->dev;
+ skb->dev = dev->master;
+ }
+}
+
+static void net_tx_action(struct softirq_action *h)
+{
+ struct softnet_data *sd = &__get_cpu_var(softnet_data);
+
+ if (sd->completion_queue) {
+ struct sk_buff *clist;
+
+ local_irq_disable();
+ clist = sd->completion_queue;
+ sd->completion_queue = NULL;
+ local_irq_enable();
+
+ while (clist) {
+ struct sk_buff *skb = clist;
+ clist = clist->next;
+
+ BUG_TRAP(!atomic_read(&skb->users));
+ __kfree_skb(skb);
+ }
+ }
+
+ if (sd->output_queue) {
+ struct net_device *head;
+
+ local_irq_disable();
+ head = sd->output_queue;
+ sd->output_queue = NULL;
+ local_irq_enable();
+
+ while (head) {
+ struct net_device *dev = head;
+ head = head->next_sched;
+
+ smp_mb__before_clear_bit();
+ clear_bit(__LINK_STATE_SCHED, &dev->state);
+
+ if (spin_trylock(&dev->queue_lock)) {
+ qdisc_run(dev);
+ spin_unlock(&dev->queue_lock);
+ } else {
+ netif_schedule(dev);
+ }
+ }
+ }
+}
+
+static __inline__ int deliver_skb(struct sk_buff *skb,
+ struct packet_type *pt_prev)
+{
+ atomic_inc(&skb->users);
+ return pt_prev->func(skb, skb->dev, pt_prev);
+}
+
+#if defined(CONFIG_BRIDGE) || defined (CONFIG_BRIDGE_MODULE)
+int (*br_handle_frame_hook)(struct net_bridge_port *p, struct sk_buff **pskb);
+
+static __inline__ int handle_bridge(struct sk_buff **pskb,
+ struct packet_type **pt_prev, int *ret)
+{
+ struct net_bridge_port *port;
+
+ if ((*pskb)->pkt_type == PACKET_LOOPBACK ||
+ (port = rcu_dereference((*pskb)->dev->br_port)) == NULL)
+ return 0;
+
+ if (*pt_prev) {
+ *ret = deliver_skb(*pskb, *pt_prev);
+ *pt_prev = NULL;
+ }
+
+ return br_handle_frame_hook(port, pskb);
+}
+#else
+#define handle_bridge(skb, pt_prev, ret) (0)
+#endif
+
+#ifdef CONFIG_NET_CLS_ACT
+/* TODO: Maybe we should just force sch_ingress to be compiled in
+ * when CONFIG_NET_CLS_ACT is? otherwise some useless instructions
+ * a compare and 2 stores extra right now if we dont have it on
+ * but have CONFIG_NET_CLS_ACT
+ * NOTE: This doesnt stop any functionality; if you dont have
+ * the ingress scheduler, you just cant add policies on ingress.
+ *
+ */
+static int ing_filter(struct sk_buff *skb)
+{
+ struct Qdisc *q;
+ struct net_device *dev = skb->dev;
+ int result = TC_ACT_OK;
+
+ if (dev->qdisc_ingress) {
+ __u32 ttl = (__u32) G_TC_RTTL(skb->tc_verd);
+ if (MAX_RED_LOOP < ttl++) {
+ printk("Redir loop detected Dropping packet (%s->%s)\n",
+ skb->input_dev?skb->input_dev->name:"??",skb->dev->name);
+ return TC_ACT_SHOT;
+ }
+
+ skb->tc_verd = SET_TC_RTTL(skb->tc_verd,ttl);
+
+ skb->tc_verd = SET_TC_AT(skb->tc_verd,AT_INGRESS);
+ if (NULL == skb->input_dev) {
+ skb->input_dev = skb->dev;
+ printk("ing_filter: fixed %s out %s\n",skb->input_dev->name,skb->dev->name);
+ }
+ spin_lock(&dev->ingress_lock);
+ if ((q = dev->qdisc_ingress) != NULL)
+ result = q->enqueue(skb, q);
+ spin_unlock(&dev->ingress_lock);
+
+ }
+
+ return result;
+}
+#endif
+
+int netif_receive_skb(struct sk_buff *skb)
+{
+ struct packet_type *ptype, *pt_prev;
+ int ret = NET_RX_DROP;
+ unsigned short type;
+
+#ifdef CONFIG_NETPOLL
+ if (skb->dev->netpoll_rx && skb->dev->poll && netpoll_rx(skb)) {
+ kfree_skb(skb);
+ return NET_RX_DROP;
+ }
+#endif
+
+ if (!skb->stamp.tv_sec)
+ net_timestamp(&skb->stamp);
+
+ skb_bond(skb);
+
+ __get_cpu_var(netdev_rx_stat).total++;
+
+ skb->h.raw = skb->nh.raw = skb->data;
+ skb->mac_len = skb->nh.raw - skb->mac.raw;
+
+ pt_prev = NULL;
+
+ rcu_read_lock();
+
+#ifdef CONFIG_NET_CLS_ACT
+ if (skb->tc_verd & TC_NCLS) {
+ skb->tc_verd = CLR_TC_NCLS(skb->tc_verd);
+ goto ncls;
+ }
+#endif
+
+ switch (skb->ip_summed) {
+ case CHECKSUM_UNNECESSARY:
+ skb->proto_csum_valid = 1;
+ break;
+ case CHECKSUM_HW:
+ /* XXX Implement me. */
+ default:
+ skb->proto_csum_valid = 0;
+ break;
+ }
+
+ list_for_each_entry_rcu(ptype, &ptype_all, list) {
+ if (!ptype->dev || ptype->dev == skb->dev) {
+ if (pt_prev)
+ ret = deliver_skb(skb, pt_prev);
+ pt_prev = ptype;
+ }
+ }
+
+#ifdef CONFIG_NET_CLS_ACT
+ if (pt_prev) {
+ ret = deliver_skb(skb, pt_prev);
+ pt_prev = NULL; /* noone else should process this after*/
+ } else {
+ skb->tc_verd = SET_TC_OK2MUNGE(skb->tc_verd);
+ }
+
+ ret = ing_filter(skb);
+
+ if (ret == TC_ACT_SHOT || (ret == TC_ACT_STOLEN)) {
+ kfree_skb(skb);
+ goto out;
+ }
+
+ skb->tc_verd = 0;
+ncls:
+#endif
+
+ handle_diverter(skb);
+
+ if (handle_bridge(&skb, &pt_prev, &ret))
+ goto out;
+
+ type = skb->protocol;
+ list_for_each_entry_rcu(ptype, &ptype_base[ntohs(type)&15], list) {
+ if (ptype->type == type &&
+ (!ptype->dev || ptype->dev == skb->dev)) {
+ if (pt_prev)
+ ret = deliver_skb(skb, pt_prev);
+ pt_prev = ptype;
+ }
+ }
+
+ if (pt_prev) {
+ ret = pt_prev->func(skb, skb->dev, pt_prev);
+ } else {
+ kfree_skb(skb);
+ /* Jamal, now you will not able to escape explaining
+ * me how you were going to use this. :-)
+ */
+ ret = NET_RX_DROP;
+ }
+
+out:
+ rcu_read_unlock();
+ return ret;
+}
+
+static int process_backlog(struct net_device *backlog_dev, int *budget)
+{
+ int work = 0;
+ int quota = min(backlog_dev->quota, *budget);
+ struct softnet_data *queue = &__get_cpu_var(softnet_data);
+ unsigned long start_time = jiffies;
+
+ for (;;) {
+ struct sk_buff *skb;
+ struct net_device *dev;
+
+ local_irq_disable();
+ skb = __skb_dequeue(&queue->input_pkt_queue);
+ if (!skb)
+ goto job_done;
+ local_irq_enable();
+
+ dev = skb->dev;
+
+ netif_receive_skb(skb);
+
+ dev_put(dev);
+
+ work++;
+
+ if (work >= quota || jiffies - start_time > 1)
+ break;
+
+ }
+
+ backlog_dev->quota -= work;
+ *budget -= work;
+ return -1;
+
+job_done:
+ backlog_dev->quota -= work;
+ *budget -= work;
+
+ list_del(&backlog_dev->poll_list);
+ smp_mb__before_clear_bit();
+ netif_poll_enable(backlog_dev);
+
+ if (queue->throttle)
+ queue->throttle = 0;
+ local_irq_enable();
+ return 0;
+}
+
+static void net_rx_action(struct softirq_action *h)
+{
+ struct softnet_data *queue = &__get_cpu_var(softnet_data);
+ unsigned long start_time = jiffies;
+ int budget = netdev_max_backlog;
+
+
+ local_irq_disable();
+
+ while (!list_empty(&queue->poll_list)) {
+ struct net_device *dev;
+
+ if (budget <= 0 || jiffies - start_time > 1)
+ goto softnet_break;
+
+ local_irq_enable();
+
+ dev = list_entry(queue->poll_list.next,
+ struct net_device, poll_list);
+
+ if (dev->quota <= 0 || dev->poll(dev, &budget)) {
+ local_irq_disable();
+ list_del(&dev->poll_list);
+ list_add_tail(&dev->poll_list, &queue->poll_list);
+ if (dev->quota < 0)
+ dev->quota += dev->weight;
+ else
+ dev->quota = dev->weight;
+ } else {
+ dev_put(dev);
+ local_irq_disable();
+ }
+ }
+out:
+ local_irq_enable();
+ return;
+
+softnet_break:
+ __get_cpu_var(netdev_rx_stat).time_squeeze++;
+ __raise_softirq_irqoff(NET_RX_SOFTIRQ);
+ goto out;
+}
+
+static gifconf_func_t * gifconf_list [NPROTO];
+
+/**
+ * register_gifconf - register a SIOCGIF handler
+ * @family: Address family
+ * @gifconf: Function handler
+ *
+ * Register protocol dependent address dumping routines. The handler
+ * that is passed must not be freed or reused until it has been replaced
+ * by another handler.
+ */
+int register_gifconf(unsigned int family, gifconf_func_t * gifconf)
+{
+ if (family >= NPROTO)
+ return -EINVAL;
+ gifconf_list[family] = gifconf;
+ return 0;
+}
+
+
+/*
+ * Map an interface index to its name (SIOCGIFNAME)
+ */
+
+/*
+ * We need this ioctl for efficient implementation of the
+ * if_indextoname() function required by the IPv6 API. Without
+ * it, we would have to search all the interfaces to find a
+ * match. --pb
+ */
+
+static int dev_ifname(struct ifreq __user *arg)
+{
+ struct net_device *dev;
+ struct ifreq ifr;
+
+ /*
+ * Fetch the caller's info block.
+ */
+
+ if (copy_from_user(&ifr, arg, sizeof(struct ifreq)))
+ return -EFAULT;
+
+ read_lock(&dev_base_lock);
+ dev = __dev_get_by_index(ifr.ifr_ifindex);
+ if (!dev) {
+ read_unlock(&dev_base_lock);
+ return -ENODEV;
+ }
+
+ strcpy(ifr.ifr_name, dev->name);
+ read_unlock(&dev_base_lock);
+
+ if (copy_to_user(arg, &ifr, sizeof(struct ifreq)))
+ return -EFAULT;
+ return 0;
+}
+
+/*
+ * Perform a SIOCGIFCONF call. This structure will change
+ * size eventually, and there is nothing I can do about it.
+ * Thus we will need a 'compatibility mode'.
+ */
+
+static int dev_ifconf(char __user *arg)
+{
+ struct ifconf ifc;
+ struct net_device *dev;
+ char __user *pos;
+ int len;
+ int total;
+ int i;
+
+ /*
+ * Fetch the caller's info block.
+ */
+
+ if (copy_from_user(&ifc, arg, sizeof(struct ifconf)))
+ return -EFAULT;
+
+ pos = ifc.ifc_buf;
+ len = ifc.ifc_len;
+
+ /*
+ * Loop over the interfaces, and write an info block for each.
+ */
+
+ total = 0;
+ for (dev = dev_base; dev; dev = dev->next) {
+ for (i = 0; i < NPROTO; i++) {
+ if (gifconf_list[i]) {
+ int done;
+ if (!pos)
+ done = gifconf_list[i](dev, NULL, 0);
+ else
+ done = gifconf_list[i](dev, pos + total,
+ len - total);
+ if (done < 0)
+ return -EFAULT;
+ total += done;
+ }
+ }
+ }
+
+ /*
+ * All done. Write the updated control block back to the caller.
+ */
+ ifc.ifc_len = total;
+
+ /*
+ * Both BSD and Solaris return 0 here, so we do too.
+ */
+ return copy_to_user(arg, &ifc, sizeof(struct ifconf)) ? -EFAULT : 0;
+}
+
+#ifdef CONFIG_PROC_FS
+/*
+ * This is invoked by the /proc filesystem handler to display a device
+ * in detail.
+ */
+static __inline__ struct net_device *dev_get_idx(loff_t pos)
+{
+ struct net_device *dev;
+ loff_t i;
+
+ for (i = 0, dev = dev_base; dev && i < pos; ++i, dev = dev->next);
+
+ return i == pos ? dev : NULL;
+}
+
+void *dev_seq_start(struct seq_file *seq, loff_t *pos)
+{
+ read_lock(&dev_base_lock);
+ return *pos ? dev_get_idx(*pos - 1) : SEQ_START_TOKEN;
+}
+
+void *dev_seq_next(struct seq_file *seq, void *v, loff_t *pos)
+{
+ ++*pos;
+ return v == SEQ_START_TOKEN ? dev_base : ((struct net_device *)v)->next;
+}
+
+void dev_seq_stop(struct seq_file *seq, void *v)
+{
+ read_unlock(&dev_base_lock);
+}
+
+static void dev_seq_printf_stats(struct seq_file *seq, struct net_device *dev)
+{
+ if (dev->get_stats) {
+ struct net_device_stats *stats = dev->get_stats(dev);
+
+ seq_printf(seq, "%6s:%8lu %7lu %4lu %4lu %4lu %5lu %10lu %9lu "
+ "%8lu %7lu %4lu %4lu %4lu %5lu %7lu %10lu\n",
+ dev->name, stats->rx_bytes, stats->rx_packets,
+ stats->rx_errors,
+ stats->rx_dropped + stats->rx_missed_errors,
+ stats->rx_fifo_errors,
+ stats->rx_length_errors + stats->rx_over_errors +
+ stats->rx_crc_errors + stats->rx_frame_errors,
+ stats->rx_compressed, stats->multicast,
+ stats->tx_bytes, stats->tx_packets,
+ stats->tx_errors, stats->tx_dropped,
+ stats->tx_fifo_errors, stats->collisions,
+ stats->tx_carrier_errors +
+ stats->tx_aborted_errors +
+ stats->tx_window_errors +
+ stats->tx_heartbeat_errors,
+ stats->tx_compressed);
+ } else
+ seq_printf(seq, "%6s: No statistics available.\n", dev->name);
+}
+
+/*
+ * Called from the PROCfs module. This now uses the new arbitrary sized
+ * /proc/net interface to create /proc/net/dev
+ */
+static int dev_seq_show(struct seq_file *seq, void *v)
+{
+ if (v == SEQ_START_TOKEN)
+ seq_puts(seq, "Inter-| Receive "
+ " | Transmit\n"
+ " face |bytes packets errs drop fifo frame "
+ "compressed multicast|bytes packets errs "
+ "drop fifo colls carrier compressed\n");
+ else
+ dev_seq_printf_stats(seq, v);
+ return 0;
+}
+
+static struct netif_rx_stats *softnet_get_online(loff_t *pos)
+{
+ struct netif_rx_stats *rc = NULL;
+
+ while (*pos < NR_CPUS)
+ if (cpu_online(*pos)) {
+ rc = &per_cpu(netdev_rx_stat, *pos);
+ break;
+ } else
+ ++*pos;
+ return rc;
+}
+
+static void *softnet_seq_start(struct seq_file *seq, loff_t *pos)
+{
+ return softnet_get_online(pos);
+}
+
+static void *softnet_seq_next(struct seq_file *seq, void *v, loff_t *pos)
+{
+ ++*pos;
+ return softnet_get_online(pos);
+}
+
+static void softnet_seq_stop(struct seq_file *seq, void *v)
+{
+}
+
+static int softnet_seq_show(struct seq_file *seq, void *v)
+{
+ struct netif_rx_stats *s = v;
+
+ seq_printf(seq, "%08x %08x %08x %08x %08x %08x %08x %08x %08x\n",
+ s->total, s->dropped, s->time_squeeze, s->throttled,
+ s->fastroute_hit, s->fastroute_success, s->fastroute_defer,
+ s->fastroute_deferred_out,
+#if 0
+ s->fastroute_latency_reduction
+#else
+ s->cpu_collision
+#endif
+ );
+ return 0;
+}
+
+static struct seq_operations dev_seq_ops = {
+ .start = dev_seq_start,
+ .next = dev_seq_next,
+ .stop = dev_seq_stop,
+ .show = dev_seq_show,
+};
+
+static int dev_seq_open(struct inode *inode, struct file *file)
+{
+ return seq_open(file, &dev_seq_ops);
+}
+
+static struct file_operations dev_seq_fops = {
+ .owner = THIS_MODULE,
+ .open = dev_seq_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = seq_release,
+};
+
+static struct seq_operations softnet_seq_ops = {
+ .start = softnet_seq_start,
+ .next = softnet_seq_next,
+ .stop = softnet_seq_stop,
+ .show = softnet_seq_show,
+};
+
+static int softnet_seq_open(struct inode *inode, struct file *file)
+{
+ return seq_open(file, &softnet_seq_ops);
+}
+
+static struct file_operations softnet_seq_fops = {
+ .owner = THIS_MODULE,
+ .open = softnet_seq_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = seq_release,
+};
+
+#ifdef WIRELESS_EXT
+extern int wireless_proc_init(void);
+#else
+#define wireless_proc_init() 0
+#endif
+
+static int __init dev_proc_init(void)
+{
+ int rc = -ENOMEM;
+
+ if (!proc_net_fops_create("dev", S_IRUGO, &dev_seq_fops))
+ goto out;
+ if (!proc_net_fops_create("softnet_stat", S_IRUGO, &softnet_seq_fops))
+ goto out_dev;
+ if (wireless_proc_init())
+ goto out_softnet;
+ rc = 0;
+out:
+ return rc;
+out_softnet:
+ proc_net_remove("softnet_stat");
+out_dev:
+ proc_net_remove("dev");
+ goto out;
+}
+#else
+#define dev_proc_init() 0
+#endif /* CONFIG_PROC_FS */
+
+
+/**
+ * netdev_set_master - set up master/slave pair
+ * @slave: slave device
+ * @master: new master device
+ *
+ * Changes the master device of the slave. Pass %NULL to break the
+ * bonding. The caller must hold the RTNL semaphore. On a failure
+ * a negative errno code is returned. On success the reference counts
+ * are adjusted, %RTM_NEWLINK is sent to the routing socket and the
+ * function returns zero.
+ */
+int netdev_set_master(struct net_device *slave, struct net_device *master)
+{
+ struct net_device *old = slave->master;
+
+ ASSERT_RTNL();
+
+ if (master) {
+ if (old)
+ return -EBUSY;
+ dev_hold(master);
+ }
+
+ slave->master = master;
+
+ synchronize_net();
+
+ if (old)
+ dev_put(old);
+
+ if (master)
+ slave->flags |= IFF_SLAVE;
+ else
+ slave->flags &= ~IFF_SLAVE;
+
+ rtmsg_ifinfo(RTM_NEWLINK, slave, IFF_SLAVE);
+ return 0;
+}
+
+/**
+ * dev_set_promiscuity - update promiscuity count on a device
+ * @dev: device
+ * @inc: modifier
+ *
+ * Add or remove promsicuity from a device. While the count in the device
+ * remains above zero the interface remains promiscuous. Once it hits zero
+ * the device reverts back to normal filtering operation. A negative inc
+ * value is used to drop promiscuity on the device.
+ */
+void dev_set_promiscuity(struct net_device *dev, int inc)
+{
+ unsigned short old_flags = dev->flags;
+
+ dev->flags |= IFF_PROMISC;
+ if ((dev->promiscuity += inc) == 0)
+ dev->flags &= ~IFF_PROMISC;
+ if (dev->flags ^ old_flags) {
+ dev_mc_upload(dev);
+ printk(KERN_INFO "device %s %s promiscuous mode\n",
+ dev->name, (dev->flags & IFF_PROMISC) ? "entered" :
+ "left");
+ }
+}
+
+/**
+ * dev_set_allmulti - update allmulti count on a device
+ * @dev: device
+ * @inc: modifier
+ *
+ * Add or remove reception of all multicast frames to a device. While the
+ * count in the device remains above zero the interface remains listening
+ * to all interfaces. Once it hits zero the device reverts back to normal
+ * filtering operation. A negative @inc value is used to drop the counter
+ * when releasing a resource needing all multicasts.
+ */
+
+void dev_set_allmulti(struct net_device *dev, int inc)
+{
+ unsigned short old_flags = dev->flags;
+
+ dev->flags |= IFF_ALLMULTI;
+ if ((dev->allmulti += inc) == 0)
+ dev->flags &= ~IFF_ALLMULTI;
+ if (dev->flags ^ old_flags)
+ dev_mc_upload(dev);
+}
+
+unsigned dev_get_flags(const struct net_device *dev)
+{
+ unsigned flags;
+
+ flags = (dev->flags & ~(IFF_PROMISC |
+ IFF_ALLMULTI |
+ IFF_RUNNING)) |
+ (dev->gflags & (IFF_PROMISC |
+ IFF_ALLMULTI));
+
+ if (netif_running(dev) && netif_carrier_ok(dev))
+ flags |= IFF_RUNNING;
+
+ return flags;
+}
+
+int dev_change_flags(struct net_device *dev, unsigned flags)
+{
+ int ret;
+ int old_flags = dev->flags;
+
+ /*
+ * Set the flags on our device.
+ */
+
+ dev->flags = (flags & (IFF_DEBUG | IFF_NOTRAILERS | IFF_NOARP |
+ IFF_DYNAMIC | IFF_MULTICAST | IFF_PORTSEL |
+ IFF_AUTOMEDIA)) |
+ (dev->flags & (IFF_UP | IFF_VOLATILE | IFF_PROMISC |
+ IFF_ALLMULTI));
+
+ /*
+ * Load in the correct multicast list now the flags have changed.
+ */
+
+ dev_mc_upload(dev);
+
+ /*
+ * Have we downed the interface. We handle IFF_UP ourselves
+ * according to user attempts to set it, rather than blindly
+ * setting it.
+ */
+
+ ret = 0;
+ if ((old_flags ^ flags) & IFF_UP) { /* Bit is different ? */
+ ret = ((old_flags & IFF_UP) ? dev_close : dev_open)(dev);
+
+ if (!ret)
+ dev_mc_upload(dev);
+ }
+
+ if (dev->flags & IFF_UP &&
+ ((old_flags ^ dev->flags) &~ (IFF_UP | IFF_PROMISC | IFF_ALLMULTI |
+ IFF_VOLATILE)))
+ notifier_call_chain(&netdev_chain, NETDEV_CHANGE, dev);
+
+ if ((flags ^ dev->gflags) & IFF_PROMISC) {
+ int inc = (flags & IFF_PROMISC) ? +1 : -1;
+ dev->gflags ^= IFF_PROMISC;
+ dev_set_promiscuity(dev, inc);
+ }
+
+ /* NOTE: order of synchronization of IFF_PROMISC and IFF_ALLMULTI
+ is important. Some (broken) drivers set IFF_PROMISC, when
+ IFF_ALLMULTI is requested not asking us and not reporting.
+ */
+ if ((flags ^ dev->gflags) & IFF_ALLMULTI) {
+ int inc = (flags & IFF_ALLMULTI) ? +1 : -1;
+ dev->gflags ^= IFF_ALLMULTI;
+ dev_set_allmulti(dev, inc);
+ }
+
+ if (old_flags ^ dev->flags)
+ rtmsg_ifinfo(RTM_NEWLINK, dev, old_flags ^ dev->flags);
+
+ return ret;
+}
+
+int dev_set_mtu(struct net_device *dev, int new_mtu)
+{
+ int err;
+
+ if (new_mtu == dev->mtu)
+ return 0;
+
+ /* MTU must be positive. */
+ if (new_mtu < 0)
+ return -EINVAL;
+
+ if (!netif_device_present(dev))
+ return -ENODEV;
+
+ err = 0;
+ if (dev->change_mtu)
+ err = dev->change_mtu(dev, new_mtu);
+ else
+ dev->mtu = new_mtu;
+ if (!err && dev->flags & IFF_UP)
+ notifier_call_chain(&netdev_chain,
+ NETDEV_CHANGEMTU, dev);
+ return err;
+}
+
+
+/*
+ * Perform the SIOCxIFxxx calls.
+ */
+static int dev_ifsioc(struct ifreq *ifr, unsigned int cmd)
+{
+ int err;
+ struct net_device *dev = __dev_get_by_name(ifr->ifr_name);
+
+ if (!dev)
+ return -ENODEV;
+
+ switch (cmd) {
+ case SIOCGIFFLAGS: /* Get interface flags */
+ ifr->ifr_flags = dev_get_flags(dev);
+ return 0;
+
+ case SIOCSIFFLAGS: /* Set interface flags */
+ return dev_change_flags(dev, ifr->ifr_flags);
+
+ case SIOCGIFMETRIC: /* Get the metric on the interface
+ (currently unused) */
+ ifr->ifr_metric = 0;
+ return 0;
+
+ case SIOCSIFMETRIC: /* Set the metric on the interface
+ (currently unused) */
+ return -EOPNOTSUPP;
+
+ case SIOCGIFMTU: /* Get the MTU of a device */
+ ifr->ifr_mtu = dev->mtu;
+ return 0;
+
+ case SIOCSIFMTU: /* Set the MTU of a device */
+ return dev_set_mtu(dev, ifr->ifr_mtu);
+
+ case SIOCGIFHWADDR:
+ if (!dev->addr_len)
+ memset(ifr->ifr_hwaddr.sa_data, 0, sizeof ifr->ifr_hwaddr.sa_data);
+ else
+ memcpy(ifr->ifr_hwaddr.sa_data, dev->dev_addr,
+ min(sizeof ifr->ifr_hwaddr.sa_data, (size_t) dev->addr_len));
+ ifr->ifr_hwaddr.sa_family = dev->type;
+ return 0;
+
+ case SIOCSIFHWADDR:
+ if (!dev->set_mac_address)
+ return -EOPNOTSUPP;
+ if (ifr->ifr_hwaddr.sa_family != dev->type)
+ return -EINVAL;
+ if (!netif_device_present(dev))
+ return -ENODEV;
+ err = dev->set_mac_address(dev, &ifr->ifr_hwaddr);
+ if (!err)
+ notifier_call_chain(&netdev_chain,
+ NETDEV_CHANGEADDR, dev);
+ return err;
+
+ case SIOCSIFHWBROADCAST:
+ if (ifr->ifr_hwaddr.sa_family != dev->type)
+ return -EINVAL;
+ memcpy(dev->broadcast, ifr->ifr_hwaddr.sa_data,
+ min(sizeof ifr->ifr_hwaddr.sa_data, (size_t) dev->addr_len));
+ notifier_call_chain(&netdev_chain,
+ NETDEV_CHANGEADDR, dev);
+ return 0;
+
+ case SIOCGIFMAP:
+ ifr->ifr_map.mem_start = dev->mem_start;
+ ifr->ifr_map.mem_end = dev->mem_end;
+ ifr->ifr_map.base_addr = dev->base_addr;
+ ifr->ifr_map.irq = dev->irq;
+ ifr->ifr_map.dma = dev->dma;
+ ifr->ifr_map.port = dev->if_port;
+ return 0;
+
+ case SIOCSIFMAP:
+ if (dev->set_config) {
+ if (!netif_device_present(dev))
+ return -ENODEV;
+ return dev->set_config(dev, &ifr->ifr_map);
+ }
+ return -EOPNOTSUPP;
+
+ case SIOCADDMULTI:
+ if (!dev->set_multicast_list ||
+ ifr->ifr_hwaddr.sa_family != AF_UNSPEC)
+ return -EINVAL;
+ if (!netif_device_present(dev))
+ return -ENODEV;
+ return dev_mc_add(dev, ifr->ifr_hwaddr.sa_data,
+ dev->addr_len, 1);
+
+ case SIOCDELMULTI:
+ if (!dev->set_multicast_list ||
+ ifr->ifr_hwaddr.sa_family != AF_UNSPEC)
+ return -EINVAL;
+ if (!netif_device_present(dev))
+ return -ENODEV;
+ return dev_mc_delete(dev, ifr->ifr_hwaddr.sa_data,
+ dev->addr_len, 1);
+
+ case SIOCGIFINDEX:
+ ifr->ifr_ifindex = dev->ifindex;
+ return 0;
+
+ case SIOCGIFTXQLEN:
+ ifr->ifr_qlen = dev->tx_queue_len;
+ return 0;
+
+ case SIOCSIFTXQLEN:
+ if (ifr->ifr_qlen < 0)
+ return -EINVAL;
+ dev->tx_queue_len = ifr->ifr_qlen;
+ return 0;
+
+ case SIOCSIFNAME:
+ ifr->ifr_newname[IFNAMSIZ-1] = '\0';
+ return dev_change_name(dev, ifr->ifr_newname);
+
+ /*
+ * Unknown or private ioctl
+ */
+
+ default:
+ if ((cmd >= SIOCDEVPRIVATE &&
+ cmd <= SIOCDEVPRIVATE + 15) ||
+ cmd == SIOCBONDENSLAVE ||
+ cmd == SIOCBONDRELEASE ||
+ cmd == SIOCBONDSETHWADDR ||
+ cmd == SIOCBONDSLAVEINFOQUERY ||
+ cmd == SIOCBONDINFOQUERY ||
+ cmd == SIOCBONDCHANGEACTIVE ||
+ cmd == SIOCGMIIPHY ||
+ cmd == SIOCGMIIREG ||
+ cmd == SIOCSMIIREG ||
+ cmd == SIOCBRADDIF ||
+ cmd == SIOCBRDELIF ||
+ cmd == SIOCWANDEV) {
+ err = -EOPNOTSUPP;
+ if (dev->do_ioctl) {
+ if (netif_device_present(dev))
+ err = dev->do_ioctl(dev, ifr,
+ cmd);
+ else
+ err = -ENODEV;
+ }
+ } else
+ err = -EINVAL;
+
+ }
+ return err;
+}
+
+/*
+ * This function handles all "interface"-type I/O control requests. The actual
+ * 'doing' part of this is dev_ifsioc above.
+ */
+
+/**
+ * dev_ioctl - network device ioctl
+ * @cmd: command to issue
+ * @arg: pointer to a struct ifreq in user space
+ *
+ * Issue ioctl functions to devices. This is normally called by the
+ * user space syscall interfaces but can sometimes be useful for
+ * other purposes. The return value is the return from the syscall if
+ * positive or a negative errno code on error.
+ */
+
+int dev_ioctl(unsigned int cmd, void __user *arg)
+{
+ struct ifreq ifr;
+ int ret;
+ char *colon;
+
+ /* One special case: SIOCGIFCONF takes ifconf argument
+ and requires shared lock, because it sleeps writing
+ to user space.
+ */
+
+ if (cmd == SIOCGIFCONF) {
+ rtnl_shlock();
+ ret = dev_ifconf((char __user *) arg);
+ rtnl_shunlock();
+ return ret;
+ }
+ if (cmd == SIOCGIFNAME)
+ return dev_ifname((struct ifreq __user *)arg);
+
+ if (copy_from_user(&ifr, arg, sizeof(struct ifreq)))
+ return -EFAULT;
+
+ ifr.ifr_name[IFNAMSIZ-1] = 0;
+
+ colon = strchr(ifr.ifr_name, ':');
+ if (colon)
+ *colon = 0;
+
+ /*
+ * See which interface the caller is talking about.
+ */
+
+ switch (cmd) {
+ /*
+ * These ioctl calls:
+ * - can be done by all.
+ * - atomic and do not require locking.
+ * - return a value
+ */
+ case SIOCGIFFLAGS:
+ case SIOCGIFMETRIC:
+ case SIOCGIFMTU:
+ case SIOCGIFHWADDR:
+ case SIOCGIFSLAVE:
+ case SIOCGIFMAP:
+ case SIOCGIFINDEX:
+ case SIOCGIFTXQLEN:
+ dev_load(ifr.ifr_name);
+ read_lock(&dev_base_lock);
+ ret = dev_ifsioc(&ifr, cmd);
+ read_unlock(&dev_base_lock);
+ if (!ret) {
+ if (colon)
+ *colon = ':';
+ if (copy_to_user(arg, &ifr,
+ sizeof(struct ifreq)))
+ ret = -EFAULT;
+ }
+ return ret;
+
+ case SIOCETHTOOL:
+ dev_load(ifr.ifr_name);
+ rtnl_lock();
+ ret = dev_ethtool(&ifr);
+ rtnl_unlock();
+ if (!ret) {
+ if (colon)
+ *colon = ':';
+ if (copy_to_user(arg, &ifr,
+ sizeof(struct ifreq)))
+ ret = -EFAULT;
+ }
+ return ret;
+
+ /*
+ * These ioctl calls:
+ * - require superuser power.
+ * - require strict serialization.
+ * - return a value
+ */
+ case SIOCGMIIPHY:
+ case SIOCGMIIREG:
+ case SIOCSIFNAME:
+ if (!capable(CAP_NET_ADMIN))
+ return -EPERM;
+ dev_load(ifr.ifr_name);
+ rtnl_lock();
+ ret = dev_ifsioc(&ifr, cmd);
+ rtnl_unlock();
+ if (!ret) {
+ if (colon)
+ *colon = ':';
+ if (copy_to_user(arg, &ifr,
+ sizeof(struct ifreq)))
+ ret = -EFAULT;
+ }
+ return ret;
+
+ /*
+ * These ioctl calls:
+ * - require superuser power.
+ * - require strict serialization.
+ * - do not return a value
+ */
+ case SIOCSIFFLAGS:
+ case SIOCSIFMETRIC:
+ case SIOCSIFMTU:
+ case SIOCSIFMAP:
+ case SIOCSIFHWADDR:
+ case SIOCSIFSLAVE:
+ case SIOCADDMULTI:
+ case SIOCDELMULTI:
+ case SIOCSIFHWBROADCAST:
+ case SIOCSIFTXQLEN:
+ case SIOCSMIIREG:
+ case SIOCBONDENSLAVE:
+ case SIOCBONDRELEASE:
+ case SIOCBONDSETHWADDR:
+ case SIOCBONDSLAVEINFOQUERY:
+ case SIOCBONDINFOQUERY:
+ case SIOCBONDCHANGEACTIVE:
+ case SIOCBRADDIF:
+ case SIOCBRDELIF:
+ if (!capable(CAP_NET_ADMIN))
+ return -EPERM;
+ dev_load(ifr.ifr_name);
+ rtnl_lock();
+ ret = dev_ifsioc(&ifr, cmd);
+ rtnl_unlock();
+ return ret;
+
+ case SIOCGIFMEM:
+ /* Get the per device memory space. We can add this but
+ * currently do not support it */
+ case SIOCSIFMEM:
+ /* Set the per device memory buffer space.
+ * Not applicable in our case */
+ case SIOCSIFLINK:
+ return -EINVAL;
+
+ /*
+ * Unknown or private ioctl.
+ */
+ default:
+ if (cmd == SIOCWANDEV ||
+ (cmd >= SIOCDEVPRIVATE &&
+ cmd <= SIOCDEVPRIVATE + 15)) {
+ dev_load(ifr.ifr_name);
+ rtnl_lock();
+ ret = dev_ifsioc(&ifr, cmd);
+ rtnl_unlock();
+ if (!ret && copy_to_user(arg, &ifr,
+ sizeof(struct ifreq)))
+ ret = -EFAULT;
+ return ret;
+ }
+#ifdef WIRELESS_EXT
+ /* Take care of Wireless Extensions */
+ if (cmd >= SIOCIWFIRST && cmd <= SIOCIWLAST) {
+ /* If command is `set a parameter', or
+ * `get the encoding parameters', check if
+ * the user has the right to do it */
+ if (IW_IS_SET(cmd) || cmd == SIOCGIWENCODE) {
+ if (!capable(CAP_NET_ADMIN))
+ return -EPERM;
+ }
+ dev_load(ifr.ifr_name);
+ rtnl_lock();
+ /* Follow me in net/core/wireless.c */
+ ret = wireless_process_ioctl(&ifr, cmd);
+ rtnl_unlock();
+ if (IW_IS_GET(cmd) &&
+ copy_to_user(arg, &ifr,
+ sizeof(struct ifreq)))
+ ret = -EFAULT;
+ return ret;
+ }
+#endif /* WIRELESS_EXT */
+ return -EINVAL;
+ }
+}
+
+
+/**
+ * dev_new_index - allocate an ifindex
+ *
+ * Returns a suitable unique value for a new device interface
+ * number. The caller must hold the rtnl semaphore or the
+ * dev_base_lock to be sure it remains unique.
+ */
+static int dev_new_index(void)
+{
+ static int ifindex;
+ for (;;) {
+ if (++ifindex <= 0)
+ ifindex = 1;
+ if (!__dev_get_by_index(ifindex))
+ return ifindex;
+ }
+}
+
+static int dev_boot_phase = 1;
+
+/* Delayed registration/unregisteration */
+static DEFINE_SPINLOCK(net_todo_list_lock);
+static struct list_head net_todo_list = LIST_HEAD_INIT(net_todo_list);
+
+static inline void net_set_todo(struct net_device *dev)
+{
+ spin_lock(&net_todo_list_lock);
+ list_add_tail(&dev->todo_list, &net_todo_list);
+ spin_unlock(&net_todo_list_lock);
+}
+
+/**
+ * register_netdevice - register a network device
+ * @dev: device to register
+ *
+ * Take a completed network device structure and add it to the kernel
+ * interfaces. A %NETDEV_REGISTER message is sent to the netdev notifier
+ * chain. 0 is returned on success. A negative errno code is returned
+ * on a failure to set up the device, or if the name is a duplicate.
+ *
+ * Callers must hold the rtnl semaphore. You may want
+ * register_netdev() instead of this.
+ *
+ * BUGS:
+ * The locking appears insufficient to guarantee two parallel registers
+ * will not get the same name.
+ */
+
+int register_netdevice(struct net_device *dev)
+{
+ struct hlist_head *head;
+ struct hlist_node *p;
+ int ret;
+
+ BUG_ON(dev_boot_phase);
+ ASSERT_RTNL();
+
+ /* When net_device's are persistent, this will be fatal. */
+ BUG_ON(dev->reg_state != NETREG_UNINITIALIZED);
+
+ spin_lock_init(&dev->queue_lock);
+ spin_lock_init(&dev->xmit_lock);
+ dev->xmit_lock_owner = -1;
+#ifdef CONFIG_NET_CLS_ACT
+ spin_lock_init(&dev->ingress_lock);
+#endif
+
+ ret = alloc_divert_blk(dev);
+ if (ret)
+ goto out;
+
+ dev->iflink = -1;
+
+ /* Init, if this function is available */
+ if (dev->init) {
+ ret = dev->init(dev);
+ if (ret) {
+ if (ret > 0)
+ ret = -EIO;
+ goto out_err;
+ }
+ }
+
+ if (!dev_valid_name(dev->name)) {
+ ret = -EINVAL;
+ goto out_err;
+ }
+
+ dev->ifindex = dev_new_index();
+ if (dev->iflink == -1)
+ dev->iflink = dev->ifindex;
+
+ /* Check for existence of name */
+ head = dev_name_hash(dev->name);
+ hlist_for_each(p, head) {
+ struct net_device *d
+ = hlist_entry(p, struct net_device, name_hlist);
+ if (!strncmp(d->name, dev->name, IFNAMSIZ)) {
+ ret = -EEXIST;
+ goto out_err;
+ }
+ }
+
+ /* Fix illegal SG+CSUM combinations. */
+ if ((dev->features & NETIF_F_SG) &&
+ !(dev->features & (NETIF_F_IP_CSUM |
+ NETIF_F_NO_CSUM |
+ NETIF_F_HW_CSUM))) {
+ printk("%s: Dropping NETIF_F_SG since no checksum feature.\n",
+ dev->name);
+ dev->features &= ~NETIF_F_SG;
+ }
+
+ /* TSO requires that SG is present as well. */
+ if ((dev->features & NETIF_F_TSO) &&
+ !(dev->features & NETIF_F_SG)) {
+ printk("%s: Dropping NETIF_F_TSO since no SG feature.\n",
+ dev->name);
+ dev->features &= ~NETIF_F_TSO;
+ }
+
+ /*
+ * nil rebuild_header routine,
+ * that should be never called and used as just bug trap.
+ */
+
+ if (!dev->rebuild_header)
+ dev->rebuild_header = default_rebuild_header;
+
+ /*
+ * Default initial state at registry is that the
+ * device is present.
+ */
+
+ set_bit(__LINK_STATE_PRESENT, &dev->state);
+
+ dev->next = NULL;
+ dev_init_scheduler(dev);
+ write_lock_bh(&dev_base_lock);
+ *dev_tail = dev;
+ dev_tail = &dev->next;
+ hlist_add_head(&dev->name_hlist, head);
+ hlist_add_head(&dev->index_hlist, dev_index_hash(dev->ifindex));
+ dev_hold(dev);
+ dev->reg_state = NETREG_REGISTERING;
+ write_unlock_bh(&dev_base_lock);
+
+ /* Notify protocols, that a new device appeared. */
+ notifier_call_chain(&netdev_chain, NETDEV_REGISTER, dev);
+
+ /* Finish registration after unlock */
+ net_set_todo(dev);
+ ret = 0;
+
+out:
+ return ret;
+out_err:
+ free_divert_blk(dev);
+ goto out;
+}
+
+/**
+ * register_netdev - register a network device
+ * @dev: device to register
+ *
+ * Take a completed network device structure and add it to the kernel
+ * interfaces. A %NETDEV_REGISTER message is sent to the netdev notifier
+ * chain. 0 is returned on success. A negative errno code is returned
+ * on a failure to set up the device, or if the name is a duplicate.
+ *
+ * This is a wrapper around register_netdev that takes the rtnl semaphore
+ * and expands the device name if you passed a format string to
+ * alloc_netdev.
+ */
+int register_netdev(struct net_device *dev)
+{
+ int err;
+
+ rtnl_lock();
+
+ /*
+ * If the name is a format string the caller wants us to do a
+ * name allocation.
+ */
+ if (strchr(dev->name, '%')) {
+ err = dev_alloc_name(dev, dev->name);
+ if (err < 0)
+ goto out;
+ }
+
+ /*
+ * Back compatibility hook. Kill this one in 2.5
+ */
+ if (dev->name[0] == 0 || dev->name[0] == ' ') {
+ err = dev_alloc_name(dev, "eth%d");
+ if (err < 0)
+ goto out;
+ }
+
+ err = register_netdevice(dev);
+out:
+ rtnl_unlock();
+ return err;
+}
+EXPORT_SYMBOL(register_netdev);
+
+/*
+ * netdev_wait_allrefs - wait until all references are gone.
+ *
+ * This is called when unregistering network devices.
+ *
+ * Any protocol or device that holds a reference should register
+ * for netdevice notification, and cleanup and put back the
+ * reference if they receive an UNREGISTER event.
+ * We can get stuck here if buggy protocols don't correctly
+ * call dev_put.
+ */
+static void netdev_wait_allrefs(struct net_device *dev)
+{
+ unsigned long rebroadcast_time, warning_time;
+
+ rebroadcast_time = warning_time = jiffies;
+ while (atomic_read(&dev->refcnt) != 0) {
+ if (time_after(jiffies, rebroadcast_time + 1 * HZ)) {
+ rtnl_shlock();
+
+ /* Rebroadcast unregister notification */
+ notifier_call_chain(&netdev_chain,
+ NETDEV_UNREGISTER, dev);
+
+ if (test_bit(__LINK_STATE_LINKWATCH_PENDING,
+ &dev->state)) {
+ /* We must not have linkwatch events
+ * pending on unregister. If this
+ * happens, we simply run the queue
+ * unscheduled, resulting in a noop
+ * for this device.
+ */
+ linkwatch_run_queue();
+ }
+
+ rtnl_shunlock();
+
+ rebroadcast_time = jiffies;
+ }
+
+ msleep(250);
+
+ if (time_after(jiffies, warning_time + 10 * HZ)) {
+ printk(KERN_EMERG "unregister_netdevice: "
+ "waiting for %s to become free. Usage "
+ "count = %d\n",
+ dev->name, atomic_read(&dev->refcnt));
+ warning_time = jiffies;
+ }
+ }
+}
+
+/* The sequence is:
+ *
+ * rtnl_lock();
+ * ...
+ * register_netdevice(x1);
+ * register_netdevice(x2);
+ * ...
+ * unregister_netdevice(y1);
+ * unregister_netdevice(y2);
+ * ...
+ * rtnl_unlock();
+ * free_netdev(y1);
+ * free_netdev(y2);
+ *
+ * We are invoked by rtnl_unlock() after it drops the semaphore.
+ * This allows us to deal with problems:
+ * 1) We can create/delete sysfs objects which invoke hotplug
+ * without deadlocking with linkwatch via keventd.
+ * 2) Since we run with the RTNL semaphore not held, we can sleep
+ * safely in order to wait for the netdev refcnt to drop to zero.
+ */
+static DECLARE_MUTEX(net_todo_run_mutex);
+void netdev_run_todo(void)
+{
+ struct list_head list = LIST_HEAD_INIT(list);
+ int err;
+
+
+ /* Need to guard against multiple cpu's getting out of order. */
+ down(&net_todo_run_mutex);
+
+ /* Not safe to do outside the semaphore. We must not return
+ * until all unregister events invoked by the local processor
+ * have been completed (either by this todo run, or one on
+ * another cpu).
+ */
+ if (list_empty(&net_todo_list))
+ goto out;
+
+ /* Snapshot list, allow later requests */
+ spin_lock(&net_todo_list_lock);
+ list_splice_init(&net_todo_list, &list);
+ spin_unlock(&net_todo_list_lock);
+
+ while (!list_empty(&list)) {
+ struct net_device *dev
+ = list_entry(list.next, struct net_device, todo_list);
+ list_del(&dev->todo_list);
+
+ switch(dev->reg_state) {
+ case NETREG_REGISTERING:
+ err = netdev_register_sysfs(dev);
+ if (err)
+ printk(KERN_ERR "%s: failed sysfs registration (%d)\n",
+ dev->name, err);
+ dev->reg_state = NETREG_REGISTERED;
+ break;
+
+ case NETREG_UNREGISTERING:
+ netdev_unregister_sysfs(dev);
+ dev->reg_state = NETREG_UNREGISTERED;
+
+ netdev_wait_allrefs(dev);
+
+ /* paranoia */
+ BUG_ON(atomic_read(&dev->refcnt));
+ BUG_TRAP(!dev->ip_ptr);
+ BUG_TRAP(!dev->ip6_ptr);
+ BUG_TRAP(!dev->dn_ptr);
+
+
+ /* It must be the very last action,
+ * after this 'dev' may point to freed up memory.
+ */
+ if (dev->destructor)
+ dev->destructor(dev);
+ break;
+
+ default:
+ printk(KERN_ERR "network todo '%s' but state %d\n",
+ dev->name, dev->reg_state);
+ break;
+ }
+ }
+
+out:
+ up(&net_todo_run_mutex);
+}
+
+/**
+ * alloc_netdev - allocate network device
+ * @sizeof_priv: size of private data to allocate space for
+ * @name: device name format string
+ * @setup: callback to initialize device
+ *
+ * Allocates a struct net_device with private data area for driver use
+ * and performs basic initialization.
+ */
+struct net_device *alloc_netdev(int sizeof_priv, const char *name,
+ void (*setup)(struct net_device *))
+{
+ void *p;
+ struct net_device *dev;
+ int alloc_size;
+
+ /* ensure 32-byte alignment of both the device and private area */
+ alloc_size = (sizeof(*dev) + NETDEV_ALIGN_CONST) & ~NETDEV_ALIGN_CONST;
+ alloc_size += sizeof_priv + NETDEV_ALIGN_CONST;
+
+ p = kmalloc(alloc_size, GFP_KERNEL);
+ if (!p) {
+ printk(KERN_ERR "alloc_dev: Unable to allocate device.\n");
+ return NULL;
+ }
+ memset(p, 0, alloc_size);
+
+ dev = (struct net_device *)
+ (((long)p + NETDEV_ALIGN_CONST) & ~NETDEV_ALIGN_CONST);
+ dev->padded = (char *)dev - (char *)p;
+
+ if (sizeof_priv)
+ dev->priv = netdev_priv(dev);
+
+ setup(dev);
+ strcpy(dev->name, name);
+ return dev;
+}
+EXPORT_SYMBOL(alloc_netdev);
+
+/**
+ * free_netdev - free network device
+ * @dev: device
+ *
+ * This function does the last stage of destroying an allocated device
+ * interface. The reference to the device object is released.
+ * If this is the last reference then it will be freed.
+ */
+void free_netdev(struct net_device *dev)
+{
+#ifdef CONFIG_SYSFS
+ /* Compatiablity with error handling in drivers */
+ if (dev->reg_state == NETREG_UNINITIALIZED) {
+ kfree((char *)dev - dev->padded);
+ return;
+ }
+
+ BUG_ON(dev->reg_state != NETREG_UNREGISTERED);
+ dev->reg_state = NETREG_RELEASED;
+
+ /* will free via class release */
+ class_device_put(&dev->class_dev);
+#else
+ kfree((char *)dev - dev->padded);
+#endif
+}
+
+/* Synchronize with packet receive processing. */
+void synchronize_net(void)
+{
+ might_sleep();
+ synchronize_kernel();
+}
+
+/**
+ * unregister_netdevice - remove device from the kernel
+ * @dev: device
+ *
+ * This function shuts down a device interface and removes it
+ * from the kernel tables. On success 0 is returned, on a failure
+ * a negative errno code is returned.
+ *
+ * Callers must hold the rtnl semaphore. You may want
+ * unregister_netdev() instead of this.
+ */
+
+int unregister_netdevice(struct net_device *dev)
+{
+ struct net_device *d, **dp;
+
+ BUG_ON(dev_boot_phase);
+ ASSERT_RTNL();
+
+ /* Some devices call without registering for initialization unwind. */
+ if (dev->reg_state == NETREG_UNINITIALIZED) {
+ printk(KERN_DEBUG "unregister_netdevice: device %s/%p never "
+ "was registered\n", dev->name, dev);
+ return -ENODEV;
+ }
+
+ BUG_ON(dev->reg_state != NETREG_REGISTERED);
+
+ /* If device is running, close it first. */
+ if (dev->flags & IFF_UP)
+ dev_close(dev);
+
+ /* And unlink it from device chain. */
+ for (dp = &dev_base; (d = *dp) != NULL; dp = &d->next) {
+ if (d == dev) {
+ write_lock_bh(&dev_base_lock);
+ hlist_del(&dev->name_hlist);
+ hlist_del(&dev->index_hlist);
+ if (dev_tail == &dev->next)
+ dev_tail = dp;
+ *dp = d->next;
+ write_unlock_bh(&dev_base_lock);
+ break;
+ }
+ }
+ if (!d) {
+ printk(KERN_ERR "unregister net_device: '%s' not found\n",
+ dev->name);
+ return -ENODEV;
+ }
+
+ dev->reg_state = NETREG_UNREGISTERING;
+
+ synchronize_net();
+
+ /* Shutdown queueing discipline. */
+ dev_shutdown(dev);
+
+
+ /* Notify protocols, that we are about to destroy
+ this device. They should clean all the things.
+ */
+ notifier_call_chain(&netdev_chain, NETDEV_UNREGISTER, dev);
+
+ /*
+ * Flush the multicast chain
+ */
+ dev_mc_discard(dev);
+
+ if (dev->uninit)
+ dev->uninit(dev);
+
+ /* Notifier chain MUST detach us from master device. */
+ BUG_TRAP(!dev->master);
+
+ free_divert_blk(dev);
+
+ /* Finish processing unregister after unlock */
+ net_set_todo(dev);
+
+ synchronize_net();
+
+ dev_put(dev);
+ return 0;
+}
+
+/**
+ * unregister_netdev - remove device from the kernel
+ * @dev: device
+ *
+ * This function shuts down a device interface and removes it
+ * from the kernel tables. On success 0 is returned, on a failure
+ * a negative errno code is returned.
+ *
+ * This is just a wrapper for unregister_netdevice that takes
+ * the rtnl semaphore. In general you want to use this and not
+ * unregister_netdevice.
+ */
+void unregister_netdev(struct net_device *dev)
+{
+ rtnl_lock();
+ unregister_netdevice(dev);
+ rtnl_unlock();
+}
+
+EXPORT_SYMBOL(unregister_netdev);
+
+#ifdef CONFIG_HOTPLUG_CPU
+static int dev_cpu_callback(struct notifier_block *nfb,
+ unsigned long action,
+ void *ocpu)
+{
+ struct sk_buff **list_skb;
+ struct net_device **list_net;
+ struct sk_buff *skb;
+ unsigned int cpu, oldcpu = (unsigned long)ocpu;
+ struct softnet_data *sd, *oldsd;
+
+ if (action != CPU_DEAD)
+ return NOTIFY_OK;
+
+ local_irq_disable();
+ cpu = smp_processor_id();
+ sd = &per_cpu(softnet_data, cpu);
+ oldsd = &per_cpu(softnet_data, oldcpu);
+
+ /* Find end of our completion_queue. */
+ list_skb = &sd->completion_queue;
+ while (*list_skb)
+ list_skb = &(*list_skb)->next;
+ /* Append completion queue from offline CPU. */
+ *list_skb = oldsd->completion_queue;
+ oldsd->completion_queue = NULL;
+
+ /* Find end of our output_queue. */
+ list_net = &sd->output_queue;
+ while (*list_net)
+ list_net = &(*list_net)->next_sched;
+ /* Append output queue from offline CPU. */
+ *list_net = oldsd->output_queue;
+ oldsd->output_queue = NULL;
+
+ raise_softirq_irqoff(NET_TX_SOFTIRQ);
+ local_irq_enable();
+
+ /* Process offline CPU's input_pkt_queue */
+ while ((skb = __skb_dequeue(&oldsd->input_pkt_queue)))
+ netif_rx(skb);
+
+ return NOTIFY_OK;
+}
+#endif /* CONFIG_HOTPLUG_CPU */
+
+
+/*
+ * Initialize the DEV module. At boot time this walks the device list and
+ * unhooks any devices that fail to initialise (normally hardware not
+ * present) and leaves us with a valid list of present and active devices.
+ *
+ */
+
+/*
+ * This is called single threaded during boot, so no need
+ * to take the rtnl semaphore.
+ */
+static int __init net_dev_init(void)
+{
+ int i, rc = -ENOMEM;
+
+ BUG_ON(!dev_boot_phase);
+
+ net_random_init();
+
+ if (dev_proc_init())
+ goto out;
+
+ if (netdev_sysfs_init())
+ goto out;
+
+ INIT_LIST_HEAD(&ptype_all);
+ for (i = 0; i < 16; i++)
+ INIT_LIST_HEAD(&ptype_base[i]);
+
+ for (i = 0; i < ARRAY_SIZE(dev_name_head); i++)
+ INIT_HLIST_HEAD(&dev_name_head[i]);
+
+ for (i = 0; i < ARRAY_SIZE(dev_index_head); i++)
+ INIT_HLIST_HEAD(&dev_index_head[i]);
+
+ /*
+ * Initialise the packet receive queues.
+ */
+
+ for (i = 0; i < NR_CPUS; i++) {
+ struct softnet_data *queue;
+
+ queue = &per_cpu(softnet_data, i);
+ skb_queue_head_init(&queue->input_pkt_queue);
+ queue->throttle = 0;
+ queue->cng_level = 0;
+ queue->avg_blog = 10; /* arbitrary non-zero */
+ queue->completion_queue = NULL;
+ INIT_LIST_HEAD(&queue->poll_list);
+ set_bit(__LINK_STATE_START, &queue->backlog_dev.state);
+ queue->backlog_dev.weight = weight_p;
+ queue->backlog_dev.poll = process_backlog;
+ atomic_set(&queue->backlog_dev.refcnt, 1);
+ }
+
+#ifdef OFFLINE_SAMPLE
+ samp_timer.expires = jiffies + (10 * HZ);
+ add_timer(&samp_timer);
+#endif
+
+ dev_boot_phase = 0;
+
+ open_softirq(NET_TX_SOFTIRQ, net_tx_action, NULL);
+ open_softirq(NET_RX_SOFTIRQ, net_rx_action, NULL);
+
+ hotcpu_notifier(dev_cpu_callback, 0);
+ dst_init();
+ dev_mcast_init();
+ rc = 0;
+out:
+ return rc;
+}
+
+subsys_initcall(net_dev_init);
+
+EXPORT_SYMBOL(__dev_get_by_index);
+EXPORT_SYMBOL(__dev_get_by_name);
+EXPORT_SYMBOL(__dev_remove_pack);
+EXPORT_SYMBOL(__skb_linearize);
+EXPORT_SYMBOL(dev_add_pack);
+EXPORT_SYMBOL(dev_alloc_name);
+EXPORT_SYMBOL(dev_close);
+EXPORT_SYMBOL(dev_get_by_flags);
+EXPORT_SYMBOL(dev_get_by_index);
+EXPORT_SYMBOL(dev_get_by_name);
+EXPORT_SYMBOL(dev_ioctl);
+EXPORT_SYMBOL(dev_open);
+EXPORT_SYMBOL(dev_queue_xmit);
+EXPORT_SYMBOL(dev_remove_pack);
+EXPORT_SYMBOL(dev_set_allmulti);
+EXPORT_SYMBOL(dev_set_promiscuity);
+EXPORT_SYMBOL(dev_change_flags);
+EXPORT_SYMBOL(dev_set_mtu);
+EXPORT_SYMBOL(free_netdev);
+EXPORT_SYMBOL(netdev_boot_setup_check);
+EXPORT_SYMBOL(netdev_set_master);
+EXPORT_SYMBOL(netdev_state_change);
+EXPORT_SYMBOL(netif_receive_skb);
+EXPORT_SYMBOL(netif_rx);
+EXPORT_SYMBOL(register_gifconf);
+EXPORT_SYMBOL(register_netdevice);
+EXPORT_SYMBOL(register_netdevice_notifier);
+EXPORT_SYMBOL(skb_checksum_help);
+EXPORT_SYMBOL(synchronize_net);
+EXPORT_SYMBOL(unregister_netdevice);
+EXPORT_SYMBOL(unregister_netdevice_notifier);
+EXPORT_SYMBOL(net_enable_timestamp);
+EXPORT_SYMBOL(net_disable_timestamp);
+
+#if defined(CONFIG_BRIDGE) || defined(CONFIG_BRIDGE_MODULE)
+EXPORT_SYMBOL(br_handle_frame_hook);
+#endif
+
+#ifdef CONFIG_KMOD
+EXPORT_SYMBOL(dev_load);
+#endif
+
+EXPORT_PER_CPU_SYMBOL(softnet_data);
--- /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 1.90 2001/11/07 05:56:19 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.
+ * Robert Olsson : Removed skb_head_pool
+ *
+ * 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/module.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>
+#ifdef CONFIG_NET_CLS_ACT
+#include <net/pkt_sched.h>
+#endif
+#include <linux/string.h>
+#include <linux/skbuff.h>
+#include <linux/cache.h>
+#include <linux/rtnetlink.h>
+#include <linux/init.h>
+#include <linux/highmem.h>
+
+#include <net/protocol.h>
+#include <net/dst.h>
+#include <net/sock.h>
+#include <net/checksum.h>
+#include <net/xfrm.h>
+
+#include <asm/uaccess.h>
+#include <asm/system.h>
+
+static kmem_cache_t *skbuff_head_cache;
+
+/*
+ * 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(KERN_INFO "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(KERN_INFO "skput:under: %p:%d put:%d dev:%s",
+ here, skb->len, sz, skb->dev ? skb->dev->name : "<NULL>");
+ BUG();
+}
+
+/* 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;
+
+ /* Get the HEAD */
+ skb = kmem_cache_alloc(skbuff_head_cache,
+ gfp_mask & ~__GFP_DMA);
+ if (!skb)
+ goto out;
+
+ /* 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)
+ goto nodata;
+
+ memset(skb, 0, offsetof(struct sk_buff, truesize));
+ skb->truesize = size + sizeof(struct sk_buff);
+ atomic_set(&skb->users, 1);
+ skb->head = data;
+ skb->data = data;
+ skb->tail = data;
+ skb->end = data + size;
+
+ atomic_set(&(skb_shinfo(skb)->dataref), 1);
+ skb_shinfo(skb)->nr_frags = 0;
+ skb_shinfo(skb)->tso_size = 0;
+ skb_shinfo(skb)->tso_segs = 0;
+ skb_shinfo(skb)->frag_list = NULL;
+out:
+ return skb;
+nodata:
+ kmem_cache_free(skbuff_head_cache, skb);
+ skb = NULL;
+ goto out;
+}
+
+/**
+ * alloc_skb_from_cache - allocate a network buffer
+ * @cp: kmem_cache from which to allocate the data area
+ * (object size must be big enough for @size bytes + skb overheads)
+ * @size: size to allocate
+ * @gfp_mask: allocation mask
+ *
+ * Allocate a new &sk_buff. The returned buffer has no headroom and
+ * 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_from_cache(kmem_cache_t *cp,
+ unsigned int size, int gfp_mask)
+{
+ struct sk_buff *skb;
+ u8 *data;
+
+ /* Get the HEAD */
+ skb = kmem_cache_alloc(skbuff_head_cache,
+ gfp_mask & ~__GFP_DMA);
+ if (!skb)
+ goto out;
+
+ /* Get the DATA. */
+ size = SKB_DATA_ALIGN(size);
+ data = kmem_cache_alloc(cp, gfp_mask);
+ if (!data)
+ goto nodata;
+
+ memset(skb, 0, offsetof(struct sk_buff, truesize));
+ skb->truesize = size + sizeof(struct sk_buff);
+ atomic_set(&skb->users, 1);
+ skb->head = data;
+ skb->data = data;
+ skb->tail = data;
+ skb->end = data + size;
+
+ atomic_set(&(skb_shinfo(skb)->dataref), 1);
+ skb_shinfo(skb)->nr_frags = 0;
+ skb_shinfo(skb)->tso_size = 0;
+ skb_shinfo(skb)->tso_segs = 0;
+ skb_shinfo(skb)->frag_list = NULL;
+out:
+ return skb;
+nodata:
+ kmem_cache_free(skbuff_head_cache, skb);
+ skb = NULL;
+ goto out;
+}
+
+
+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);
+}
+
+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);
+
+ kfree(skb->head);
+ }
+}
+
+/*
+ * Free an skbuff by memory without cleaning the state.
+ */
+void kfree_skbmem(struct sk_buff *skb)
+{
+ skb_release_data(skb);
+ kmem_cache_free(skbuff_head_cache, 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);
+#ifdef CONFIG_XFRM
+ secpath_put(skb->sp);
+#endif
+ 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);
+#ifdef CONFIG_BRIDGE_NETFILTER
+ nf_bridge_put(skb->nf_bridge);
+#endif
+#endif
+/* XXX: IS this still necessary? - JHS */
+#ifdef CONFIG_NET_SCHED
+ skb->tc_index = 0;
+#ifdef CONFIG_NET_CLS_ACT
+ skb->tc_verd = 0;
+ skb->tc_classid = 0;
+#endif
+#endif
+
+ 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 = 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(real_dev);
+ C(h);
+ C(nh);
+ C(mac);
+ C(dst);
+ dst_clone(skb->dst);
+ C(sp);
+#ifdef CONFIG_INET
+ secpath_get(skb->sp);
+#endif
+ memcpy(n->cb, skb->cb, sizeof(skb->cb));
+ C(len);
+ C(data_len);
+ C(csum);
+ C(local_df);
+ n->cloned = 1;
+ C(proto_csum_valid);
+ C(proto_csum_blank);
+ C(pkt_type);
+ C(ip_summed);
+ C(priority);
+ C(protocol);
+ C(security);
+ n->destructor = NULL;
+#ifdef CONFIG_NETFILTER
+ C(nfmark);
+ C(nfcache);
+ C(nfct);
+ nf_conntrack_get(skb->nfct);
+ C(nfctinfo);
+#ifdef CONFIG_NETFILTER_DEBUG
+ C(nf_debug);
+#endif
+#ifdef CONFIG_BRIDGE_NETFILTER
+ C(nf_bridge);
+ nf_bridge_get(skb->nf_bridge);
+#endif
+#endif /*CONFIG_NETFILTER*/
+#if defined(CONFIG_HIPPI)
+ C(private);
+#endif
+#ifdef CONFIG_NET_SCHED
+ C(tc_index);
+#ifdef CONFIG_NET_CLS_ACT
+ n->tc_verd = SET_TC_VERD(skb->tc_verd,0);
+ n->tc_verd = CLR_TC_OK2MUNGE(skb->tc_verd);
+ n->tc_verd = CLR_TC_MUNGED(skb->tc_verd);
+ C(input_dev);
+ C(tc_classid);
+#endif
+
+#endif
+ C(truesize);
+ atomic_set(&n->users, 1);
+ C(head);
+ C(data);
+ C(tail);
+ C(end);
+
+ atomic_inc(&(skb_shinfo(skb)->dataref));
+ skb->cloned = 1;
+
+ 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->real_dev = old->real_dev;
+ new->priority = old->priority;
+ new->protocol = old->protocol;
+ new->dst = dst_clone(old->dst);
+#ifdef CONFIG_INET
+ new->sp = secpath_get(old->sp);
+#endif
+ 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));
+ new->local_df = old->local_df;
+ 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(old->nfct);
+ new->nfctinfo = old->nfctinfo;
+#ifdef CONFIG_NETFILTER_DEBUG
+ new->nf_debug = old->nf_debug;
+#endif
+#ifdef CONFIG_BRIDGE_NETFILTER
+ new->nf_bridge = old->nf_bridge;
+ nf_bridge_get(old->nf_bridge);
+#endif
+#endif
+#ifdef CONFIG_NET_SCHED
+#ifdef CONFIG_NET_CLS_ACT
+ new->tc_verd = old->tc_verd;
+#endif
+ new->tc_index = old->tc_index;
+#endif
+ atomic_set(&new->users, 1);
+ skb_shinfo(new)->tso_size = skb_shinfo(old)->tso_size;
+ skb_shinfo(new)->tso_segs = skb_shinfo(old)->tso_segs;
+}
+
+/**
+ * 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)
+{
+ int headerlen = skb->data - skb->head;
+ /*
+ * Allocate the copy buffer
+ */
+ struct sk_buff *n = alloc_skb(skb->end - skb->head + skb->data_len,
+ gfp_mask);
+ if (!n)
+ 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;
+}
+
+
+/**
+ * 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)
+{
+ /*
+ * Allocate the copy buffer
+ */
+ struct sk_buff *n = alloc_skb(skb->end - skb->head, gfp_mask);
+
+ if (!n)
+ goto out;
+
+ /* 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);
+out:
+ 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)
+ 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)
+ skb2 = pskb_copy(skb, GFP_ATOMIC);
+ else {
+ skb2 = skb_clone(skb, GFP_ATOMIC);
+ if (skb2 && pskb_expand_head(skb2, SKB_DATA_ALIGN(delta), 0,
+ GFP_ATOMIC)) {
+ kfree_skb(skb2);
+ skb2 = NULL;
+ }
+ }
+ return skb2;
+}
+
+
+/**
+ * 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.
+ *
+ * BUG ALERT: ip_summed is not copied. Why does this work? Is it used
+ * only by netfilter in the cases when checksum is recalculated? --ANK
+ */
+struct sk_buff *skb_copy_expand(const struct sk_buff *skb,
+ int newheadroom, int newtailroom, int gfp_mask)
+{
+ /*
+ * Allocate the copy buffer
+ */
+ struct sk_buff *n = alloc_skb(newheadroom + skb->len + newtailroom,
+ gfp_mask);
+ int head_copy_len, head_copy_off;
+
+ if (!n)
+ return NULL;
+
+ skb_reserve(n, newheadroom);
+
+ /* Set the tail pointer and length */
+ skb_put(n, skb->len);
+
+ head_copy_len = skb_headroom(skb);
+ head_copy_off = 0;
+ if (newheadroom <= head_copy_len)
+ head_copy_len = newheadroom;
+ else
+ head_copy_off = newheadroom - head_copy_len;
+
+ /* Copy the linear header and data. */
+ if (skb_copy_bits(skb, -head_copy_len, n->head + head_copy_off,
+ skb->len + head_copy_len))
+ BUG();
+
+ copy_skb_header(n, skb);
+
+ return n;
+}
+
+/**
+ * skb_pad - zero pad the tail of an skb
+ * @skb: buffer to pad
+ * @pad: space to pad
+ *
+ * Ensure that a buffer is followed by a padding area that is zero
+ * filled. Used by network drivers which may DMA or transfer data
+ * beyond the buffer end onto the wire.
+ *
+ * May return NULL in out of memory cases.
+ */
+
+struct sk_buff *skb_pad(struct sk_buff *skb, int pad)
+{
+ struct sk_buff *nskb;
+
+ /* If the skbuff is non linear tailroom is always zero.. */
+ if (skb_tailroom(skb) >= pad) {
+ memset(skb->data+skb->len, 0, pad);
+ return skb;
+ }
+
+ nskb = skb_copy_expand(skb, skb_headroom(skb), skb_tailroom(skb) + pad, GFP_ATOMIC);
+ kfree_skb(skb);
+ if (nskb)
+ memset(nskb->data+nskb->len, 0, pad);
+ return nskb;
+}
+
+/* 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)
+{
+ /* 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.
+ */
+ int i, k, 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)
+ 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)
+ 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)
+ return NULL;
+ insp = list->next;
+ list = clone;
+ } else {
+ /* This may be pulled without
+ * problems. */
+ insp = list;
+ }
+ if (!pskb_pull(list, eat)) {
+ 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_headlen(skb);
+
+ 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 = skb_shinfo(skb)->frag_list;
+
+ for (; 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)
+ return 0;
+
+fault:
+ return -EFAULT;
+}
+
+/* Keep iterating until skb_iter_next returns false. */
+void skb_iter_first(const struct sk_buff *skb, struct skb_iter *i)
+{
+ i->len = skb_headlen(skb);
+ i->data = (unsigned char *)skb->data;
+ i->nextfrag = 0;
+ i->fraglist = NULL;
+}
+
+int skb_iter_next(const struct sk_buff *skb, struct skb_iter *i)
+{
+ /* Unmap previous, if not head fragment. */
+ if (i->nextfrag)
+ kunmap_skb_frag(i->data);
+
+ if (i->fraglist) {
+ fraglist:
+ /* We're iterating through fraglist. */
+ if (i->nextfrag < skb_shinfo(i->fraglist)->nr_frags) {
+ i->data = kmap_skb_frag(&skb_shinfo(i->fraglist)
+ ->frags[i->nextfrag]);
+ i->len = skb_shinfo(i->fraglist)->frags[i->nextfrag]
+ .size;
+ i->nextfrag++;
+ return 1;
+ }
+ /* Fragments with fragments? Too hard! */
+ BUG_ON(skb_shinfo(i->fraglist)->frag_list);
+ i->fraglist = i->fraglist->next;
+ if (!i->fraglist)
+ goto end;
+
+ i->len = skb_headlen(i->fraglist);
+ i->data = i->fraglist->data;
+ i->nextfrag = 0;
+ return 1;
+ }
+
+ if (i->nextfrag < skb_shinfo(skb)->nr_frags) {
+ i->data = kmap_skb_frag(&skb_shinfo(skb)->frags[i->nextfrag]);
+ i->len = skb_shinfo(skb)->frags[i->nextfrag].size;
+ i->nextfrag++;
+ return 1;
+ }
+
+ i->fraglist = skb_shinfo(skb)->frag_list;
+ if (i->fraglist)
+ goto fraglist;
+
+end:
+ /* Bug trap for callers */
+ i->data = NULL;
+ return 0;
+}
+
+void skb_iter_abort(const struct sk_buff *skb, struct skb_iter *i)
+{
+ /* Unmap previous, if not head fragment. */
+ if (i->data && i->nextfrag)
+ kunmap_skb_frag(i->data);
+ /* Bug trap for callers */
+ i->data = NULL;
+}
+
+/* Checksum skb data. */
+
+unsigned int skb_checksum(const struct sk_buff *skb, int offset,
+ int len, unsigned int csum)
+{
+ int start = skb_headlen(skb);
+ int i, copy = start - offset;
+ int pos = 0;
+
+ /* Checksum header. */
+ if (copy > 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 = skb_shinfo(skb)->frag_list;
+
+ for (; 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)
+ 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 start = skb_headlen(skb);
+ int i, copy = start - offset;
+ int pos = 0;
+
+ /* Copy header. */
+ if (copy > 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 = skb_shinfo(skb)->frag_list;
+
+ for (; 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)
+ 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_headlen(skb);
+
+ if (csstart > skb_headlen(skb))
+ 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);
+ }
+}
+
+/**
+ * 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.
+ */
+
+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;
+}
+
+/**
+ * skb_dequeue_tail - remove from the tail of the queue
+ * @list: list to dequeue from
+ *
+ * Remove the tail 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.
+ */
+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;
+}
+
+/**
+ * skb_queue_purge - empty a list
+ * @list: list to empty
+ *
+ * Delete all buffers on an &sk_buff list. Each buffer is removed from
+ * the list and one reference dropped. This function takes the list
+ * lock and is atomic with respect to other list locking functions.
+ */
+void skb_queue_purge(struct sk_buff_head *list)
+{
+ struct sk_buff *skb;
+ while ((skb = skb_dequeue(list)) != NULL)
+ kfree_skb(skb);
+}
+
+/**
+ * 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.
+ */
+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 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.
+ */
+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_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.
+ */
+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);
+ }
+}
+
+
+/**
+ * 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.
+ */
+
+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);
+}
+
+
+/**
+ * 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.
+ */
+
+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);
+}
+
+#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
+
+static inline void skb_split_inside_header(struct sk_buff *skb,
+ struct sk_buff* skb1,
+ const u32 len, const int pos)
+{
+ int i;
+
+ memcpy(skb_put(skb1, pos - len), skb->data + len, pos - len);
+
+ /* And move data appendix as is. */
+ for (i = 0; i < skb_shinfo(skb)->nr_frags; i++)
+ skb_shinfo(skb1)->frags[i] = skb_shinfo(skb)->frags[i];
+
+ skb_shinfo(skb1)->nr_frags = skb_shinfo(skb)->nr_frags;
+ skb_shinfo(skb)->nr_frags = 0;
+ skb1->data_len = skb->data_len;
+ skb1->len += skb1->data_len;
+ skb->data_len = 0;
+ skb->len = len;
+ skb->tail = skb->data + len;
+}
+
+static inline void skb_split_no_header(struct sk_buff *skb,
+ struct sk_buff* skb1,
+ const u32 len, int pos)
+{
+ int i, k = 0;
+ const int nfrags = skb_shinfo(skb)->nr_frags;
+
+ skb_shinfo(skb)->nr_frags = 0;
+ skb1->len = skb1->data_len = skb->len - len;
+ skb->len = len;
+ skb->data_len = len - pos;
+
+ for (i = 0; i < nfrags; i++) {
+ int size = skb_shinfo(skb)->frags[i].size;
+
+ if (pos + size > len) {
+ skb_shinfo(skb1)->frags[k] = skb_shinfo(skb)->frags[i];
+
+ if (pos < len) {
+ /* Split frag.
+ * We have to variants in this case:
+ * 1. Move all the frag to the second
+ * part, if it is possible. F.e.
+ * this approach is mandatory for TUX,
+ * where splitting is expensive.
+ * 2. Split is accurately. We make this.
+ */
+ get_page(skb_shinfo(skb)->frags[i].page);
+ skb_shinfo(skb1)->frags[0].page_offset += len - pos;
+ skb_shinfo(skb1)->frags[0].size -= len - pos;
+ skb_shinfo(skb)->frags[i].size = len - pos;
+ skb_shinfo(skb)->nr_frags++;
+ }
+ k++;
+ } else
+ skb_shinfo(skb)->nr_frags++;
+ pos += size;
+ }
+ skb_shinfo(skb1)->nr_frags = k;
+}
+
+/**
+ * skb_split - Split fragmented skb to two parts at length len.
+ */
+void skb_split(struct sk_buff *skb, struct sk_buff *skb1, const u32 len)
+{
+ int pos = skb_headlen(skb);
+
+ if (len < pos) /* Split line is inside header. */
+ skb_split_inside_header(skb, skb1, len, pos);
+ else /* Second chunk has no header, nothing to copy. */
+ skb_split_no_header(skb, skb1, len, pos);
+}
+
+void __init skb_init(void)
+{
+ skbuff_head_cache = kmem_cache_create("skbuff_head_cache",
+ sizeof(struct sk_buff),
+ 0,
+ SLAB_HWCACHE_ALIGN,
+ NULL, NULL);
+ if (!skbuff_head_cache)
+ panic("cannot create skbuff cache");
+}
+
+EXPORT_SYMBOL(___pskb_trim);
+EXPORT_SYMBOL(__kfree_skb);
+EXPORT_SYMBOL(__pskb_pull_tail);
+EXPORT_SYMBOL(alloc_skb);
+EXPORT_SYMBOL(pskb_copy);
+EXPORT_SYMBOL(pskb_expand_head);
+EXPORT_SYMBOL(skb_checksum);
+EXPORT_SYMBOL(skb_clone);
+EXPORT_SYMBOL(skb_clone_fraglist);
+EXPORT_SYMBOL(skb_copy);
+EXPORT_SYMBOL(skb_copy_and_csum_bits);
+EXPORT_SYMBOL(skb_copy_and_csum_dev);
+EXPORT_SYMBOL(skb_copy_bits);
+EXPORT_SYMBOL(skb_copy_expand);
+EXPORT_SYMBOL(skb_over_panic);
+EXPORT_SYMBOL(skb_pad);
+EXPORT_SYMBOL(skb_realloc_headroom);
+EXPORT_SYMBOL(skb_under_panic);
+EXPORT_SYMBOL(skb_dequeue);
+EXPORT_SYMBOL(skb_dequeue_tail);
+EXPORT_SYMBOL(skb_insert);
+EXPORT_SYMBOL(skb_queue_purge);
+EXPORT_SYMBOL(skb_queue_head);
+EXPORT_SYMBOL(skb_queue_tail);
+EXPORT_SYMBOL(skb_unlink);
+EXPORT_SYMBOL(skb_append);
+EXPORT_SYMBOL(skb_split);
+EXPORT_SYMBOL(skb_iter_first);
+EXPORT_SYMBOL(skb_iter_next);
+EXPORT_SYMBOL(skb_iter_abort);
projects / xen.git / commitdiff