diff options
Diffstat (limited to 'linux-2.6-xen-sparse/include/linux/skbuff.h')
| -rw-r--r-- | linux-2.6-xen-sparse/include/linux/skbuff.h | 1510 |
1 files changed, 0 insertions, 1510 deletions
diff --git a/linux-2.6-xen-sparse/include/linux/skbuff.h b/linux-2.6-xen-sparse/include/linux/skbuff.h deleted file mode 100644 index 46ad73c420..0000000000 --- a/linux-2.6-xen-sparse/include/linux/skbuff.h +++ /dev/null @@ -1,1510 +0,0 @@ -/* - * 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/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 <linux/textsearch.h> -#include <net/checksum.h> -#include <linux/dmaengine.h> - -#define HAVE_ALLOC_SKB /* For the drivers to know */ -#define HAVE_ALIGNABLE_SKB /* Ditto 8) */ - -#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 - */ - -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 short nr_frags; - unsigned short gso_size; - /* Warning: this field is not always filled in (UFO)! */ - unsigned short gso_segs; - unsigned short gso_type; - unsigned int ip6_frag_id; - struct sk_buff *frag_list; - skb_frag_t frags[MAX_SKB_FRAGS]; -}; - -/* We divide dataref into two halves. The higher 16 bits hold references - * to the payload part of skb->data. The lower 16 bits hold references to - * the entire skb->data. It is up to the users of the skb to agree on - * where the payload starts. - * - * All users must obey the rule that the skb->data reference count must be - * greater than or equal to the payload reference count. - * - * Holding a reference to the payload part means that the user does not - * care about modifications to the header part of skb->data. - */ -#define SKB_DATAREF_SHIFT 16 -#define SKB_DATAREF_MASK ((1 << SKB_DATAREF_SHIFT) - 1) - -struct skb_timeval { - u32 off_sec; - u32 off_usec; -}; - - -enum { - SKB_FCLONE_UNAVAILABLE, - SKB_FCLONE_ORIG, - SKB_FCLONE_CLONE, -}; - -enum { - SKB_GSO_TCPV4 = 1 << 0, - SKB_GSO_UDP = 1 << 1, - - /* This indicates the skb is from an untrusted source. */ - SKB_GSO_DODGY = 1 << 2, - - /* This indicates the tcp segment has CWR set. */ - SKB_GSO_TCP_ECN = 1 << 3, - - SKB_GSO_TCPV6 = 1 << 4, -}; - -/** - * struct sk_buff - socket buffer - * @next: Next buffer in list - * @prev: Previous buffer in list - * @sk: Socket we are owned by - * @tstamp: Time we arrived - * @dev: Device we arrived on/are leaving by - * @input_dev: Device we arrived on - * @h: Transport layer header - * @nh: Network layer header - * @mac: Link layer header - * @dst: destination entry - * @sp: the security path, used for xfrm - * @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 - * @local_df: allow local fragmentation - * @cloned: Head may be cloned (check refcnt to be sure) - * @nohdr: Payload reference only, must not modify header - * @proto_data_valid: Protocol data validated since arriving at localhost - * @proto_csum_blank: Protocol csum must be added before leaving localhost - * @pkt_type: Packet class - * @fclone: skbuff clone status - * @ip_summed: Driver fed us an IP checksum - * @priority: Packet queueing priority - * @users: User count - see {datagram,tcp}.c - * @protocol: Packet protocol from driver - * @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 - * @nfct: Associated connection, if any - * @ipvs_property: skbuff is owned by ipvs - * @nfctinfo: Relationship of this skb to the connection - * @nfct_reasm: netfilter conntrack re-assembly pointer - * @nf_bridge: Saved data about a bridged frame - see br_netfilter.c - * @tc_index: Traffic control index - * @tc_verd: traffic control verdict - * @dma_cookie: a cookie to one of several possible DMA operations - * done by skb DMA functions - * @secmark: security marking - */ - -struct sk_buff { - /* These two members must be first. */ - struct sk_buff *next; - struct sk_buff *prev; - - struct sock *sk; - struct skb_timeval tstamp; - struct net_device *dev; - struct net_device *input_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[48]; - - unsigned int len, - data_len, - mac_len, - csum; - __u32 priority; - __u8 local_df:1, - cloned:1, - ip_summed:2, - nohdr:1, - nfctinfo:3; - __u8 pkt_type:3, - fclone:2, -#ifndef CONFIG_XEN - ipvs_property:1; -#else - ipvs_property:1, - proto_data_valid:1, - proto_csum_blank:1; -#endif - __be16 protocol; - - void (*destructor)(struct sk_buff *skb); -#ifdef CONFIG_NETFILTER - struct nf_conntrack *nfct; -#if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE) - struct sk_buff *nfct_reasm; -#endif -#ifdef CONFIG_BRIDGE_NETFILTER - struct nf_bridge_info *nf_bridge; -#endif - __u32 nfmark; -#endif /* CONFIG_NETFILTER */ -#ifdef CONFIG_NET_SCHED - __u16 tc_index; /* traffic control index */ -#ifdef CONFIG_NET_CLS_ACT - __u16 tc_verd; /* traffic control verdict */ -#endif -#endif -#ifdef CONFIG_NET_DMA - dma_cookie_t dma_cookie; -#endif -#ifdef CONFIG_NETWORK_SECMARK - __u32 secmark; -#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 void __kfree_skb(struct sk_buff *skb); -extern struct sk_buff *__alloc_skb(unsigned int size, - gfp_t priority, int fclone); -static inline struct sk_buff *alloc_skb(unsigned int size, - gfp_t priority) -{ - return __alloc_skb(size, priority, 0); -} - -static inline struct sk_buff *alloc_skb_fclone(unsigned int size, - gfp_t priority) -{ - return __alloc_skb(size, priority, 1); -} - -extern struct sk_buff *alloc_skb_from_cache(kmem_cache_t *cp, - unsigned int size, - gfp_t priority); -extern void kfree_skbmem(struct sk_buff *skb); -extern struct sk_buff *skb_clone(struct sk_buff *skb, - gfp_t priority); -extern struct sk_buff *skb_copy(const struct sk_buff *skb, - gfp_t priority); -extern struct sk_buff *pskb_copy(struct sk_buff *skb, - gfp_t gfp_mask); -extern int pskb_expand_head(struct sk_buff *skb, - int nhead, int ntail, - gfp_t 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, - gfp_t priority); -extern int 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); -extern void skb_truesize_bug(struct sk_buff *skb); - -static inline void skb_truesize_check(struct sk_buff *skb) -{ - if (unlikely((int)skb->truesize < sizeof(struct sk_buff) + skb->len)) - skb_truesize_bug(skb); -} - -extern int skb_append_datato_frags(struct sock *sk, struct sk_buff *skb, - int getfrag(void *from, char *to, int offset, - int len,int odd, struct sk_buff *skb), - void *from, int length); - -struct skb_seq_state -{ - __u32 lower_offset; - __u32 upper_offset; - __u32 frag_idx; - __u32 stepped_offset; - struct sk_buff *root_skb; - struct sk_buff *cur_skb; - __u8 *frag_data; -}; - -extern void skb_prepare_seq_read(struct sk_buff *skb, - unsigned int from, unsigned int to, - struct skb_seq_state *st); -extern unsigned int skb_seq_read(unsigned int consumed, const u8 **data, - struct skb_seq_state *st); -extern void skb_abort_seq_read(struct skb_seq_state *st); - -extern unsigned int skb_find_text(struct sk_buff *skb, unsigned int from, - unsigned int to, struct ts_config *config, - struct ts_state *state); - -/* 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. - */ - -/** - * skb_cloned - is the buffer a clone - * @skb: buffer to check - * - * Returns true if the buffer was generated with skb_clone() and is - * one of multiple shared copies of the buffer. Cloned buffers are - * shared data so must not be written to under normal circumstances. - */ -static inline int skb_cloned(const struct sk_buff *skb) -{ - return skb->cloned && - (atomic_read(&skb_shinfo(skb)->dataref) & SKB_DATAREF_MASK) != 1; -} - -/** - * skb_header_cloned - is the header a clone - * @skb: buffer to check - * - * Returns true if modifying the header part of the buffer requires - * the data to be copied. - */ -static inline int skb_header_cloned(const struct sk_buff *skb) -{ - int dataref; - - if (!skb->cloned) - return 0; - - dataref = atomic_read(&skb_shinfo(skb)->dataref); - dataref = (dataref & SKB_DATAREF_MASK) - (dataref >> SKB_DATAREF_SHIFT); - return dataref != 1; -} - -/** - * skb_header_release - release reference to header - * @skb: buffer to operate on - * - * Drop a reference to the header part of the buffer. This is done - * by acquiring a payload reference. You must not read from the header - * part of skb->data after this. - */ -static inline void skb_header_release(struct sk_buff *skb) -{ - BUG_ON(skb->nohdr); - skb->nohdr = 1; - atomic_add(1 << SKB_DATAREF_SHIFT, &skb_shinfo(skb)->dataref); -} - -/** - * skb_shared - is the buffer shared - * @skb: buffer to check - * - * Returns true if more than one person has a reference to this - * buffer. - */ -static inline int skb_shared(const struct sk_buff *skb) -{ - return atomic_read(&skb->users) != 1; -} - -/** - * skb_share_check - check if buffer is shared and if so clone it - * @skb: buffer to check - * @pri: priority for memory allocation - * - * If the buffer is shared the buffer is cloned and the old copy - * drops a reference. A new clone with a single reference is returned. - * If the buffer is not shared the original buffer is returned. When - * being called from interrupt status or with spinlocks held pri must - * be GFP_ATOMIC. - * - * NULL is returned on a memory allocation failure. - */ -static inline struct sk_buff *skb_share_check(struct sk_buff *skb, - gfp_t pri) -{ - might_sleep_if(pri & __GFP_WAIT); - if (skb_shared(skb)) { - struct sk_buff *nskb = skb_clone(skb, pri); - kfree_skb(skb); - skb = nskb; - } - return skb; -} - -/* - * Copy shared buffers into a new sk_buff. We effectively do COW on - * packets to handle cases where we have a local reader and forward - * and a couple of other messy ones. The normal one is tcpdumping - * a packet thats being forwarded. - */ - -/** - * skb_unshare - make a copy of a shared buffer - * @skb: buffer to check - * @pri: priority for memory allocation - * - * If the socket buffer is a clone then this function creates a new - * copy of the data, drops a reference count on the old copy and returns - * the new copy with the reference count at 1. If the buffer is not a clone - * the original buffer is returned. When called with a spinlock held or - * from interrupt state @pri must be %GFP_ATOMIC - * - * %NULL is returned on a memory allocation failure. - */ -static inline struct sk_buff *skb_unshare(struct sk_buff *skb, - gfp_t pri) -{ - might_sleep_if(pri & __GFP_WAIT); - if (skb_cloned(skb)) { - struct sk_buff *nskb = skb_copy(skb, pri); - kfree_skb(skb); /* Free our shared copy */ - skb = nskb; - } - return skb; -} - -/** - * skb_peek - * @list_: list to peek at - * - * Peek an &sk_buff. Unlike most other operations you _MUST_ - * be careful with this one. A peek leaves the buffer on the - * list and someone else may run off with it. You must hold - * the appropriate locks or have a private queue to do this. - * - * Returns %NULL for an empty list or a pointer to the head element. - * The reference count is not incremented and the reference is therefore - * volatile. Use with caution. - */ -static inline struct sk_buff *skb_peek(struct sk_buff_head *list_) -{ - struct sk_buff *list = ((struct sk_buff *)list_)->next; - if (list == (struct sk_buff *)list_) - list = NULL; - return list; -} - -/** - * skb_peek_tail - * @list_: list to peek at - * - * Peek an &sk_buff. Unlike most other operations you _MUST_ - * be careful with this one. A peek leaves the buffer on the - * list and someone else may run off with it. You must hold - * the appropriate locks or have a private queue to do this. - * - * Returns %NULL for an empty list or a pointer to the tail element. - * The reference count is not incremented and the reference is therefore - * volatile. Use with caution. - */ -static inline struct sk_buff *skb_peek_tail(struct sk_buff_head *list_) -{ - struct sk_buff *list = ((struct sk_buff *)list_)->prev; - if (list == (struct sk_buff *)list_) - list = NULL; - return list; -} - -/** - * skb_queue_len - get queue length - * @list_: list to measure - * - * Return the length of an &sk_buff queue. - */ -static inline __u32 skb_queue_len(const struct sk_buff_head *list_) -{ - return list_->qlen; -} - -/* - * This function creates a split out lock class for each invocation; - * this is needed for now since a whole lot of users of the skb-queue - * infrastructure in drivers have different locking usage (in hardirq) - * than the networking core (in softirq only). In the long run either the - * network layer or drivers should need annotation to consolidate the - * main types of usage into 3 classes. - */ -static inline void skb_queue_head_init(struct sk_buff_head *list) -{ - spin_lock_init(&list->lock); - list->prev = list->next = (struct sk_buff *)list; - list->qlen = 0; -} - -/* - * Insert an sk_buff at the start of a list. - * - * The "__skb_xxxx()" functions are the non-atomic ones that - * can only be called with interrupts disabled. - */ - -/** - * __skb_queue_after - queue a buffer at the list head - * @list: list to use - * @prev: place after this buffer - * @newsk: buffer to queue - * - * Queue a buffer int the middle of a list. This function takes no locks - * and you must therefore hold required locks before calling it. - * - * A buffer cannot be placed on two lists at the same time. - */ -static inline void __skb_queue_after(struct sk_buff_head *list, - struct sk_buff *prev, - struct sk_buff *newsk) -{ - struct sk_buff *next; - list->qlen++; - - next = prev->next; - newsk->next = next; - newsk->prev = prev; - next->prev = prev->next = newsk; -} - -/** - * __skb_queue_head - queue a buffer at the list head - * @list: list to use - * @newsk: buffer to queue - * - * Queue a buffer at the start of a list. This function takes no locks - * and you must therefore hold required locks before calling it. - * - * A buffer cannot be placed on two lists at the same time. - */ -extern void skb_queue_head(struct sk_buff_head *list, struct sk_buff *newsk); -static inline void __skb_queue_head(struct sk_buff_head *list, - struct sk_buff *newsk) -{ - __skb_queue_after(list, (struct sk_buff *)list, newsk); -} - -/** - * __skb_queue_tail - queue a buffer at the list tail - * @list: list to use - * @newsk: buffer to queue - * - * Queue a buffer at the end of a list. This function takes no locks - * and you must therefore hold required locks before calling it. - * - * A buffer cannot be placed on two lists at the same time. - */ -extern void skb_queue_tail(struct sk_buff_head *list, struct sk_buff *newsk); -static inline void __skb_queue_tail(struct sk_buff_head *list, - struct sk_buff *newsk) -{ - struct sk_buff *prev, *next; - - list->qlen++; - next = (struct sk_buff *)list; - prev = next->prev; - newsk->next = next; - newsk->prev = prev; - next->prev = prev->next = newsk; -} - - -/** - * __skb_dequeue - remove from the head of the queue - * @list: list to dequeue from - * - * Remove the head of the list. This function does not take any locks - * so must be used with appropriate locks held only. The head item is - * returned or %NULL if the list is empty. - */ -extern struct sk_buff *skb_dequeue(struct sk_buff_head *list); -static inline struct sk_buff *__skb_dequeue(struct sk_buff_head *list) -{ - struct sk_buff *next, *prev, *result; - - prev = (struct sk_buff *) list; - next = prev->next; - result = NULL; - if (next != prev) { - result = next; - next = next->next; - list->qlen--; - next->prev = prev; - prev->next = next; - result->next = result->prev = NULL; - } - return result; -} - - -/* - * Insert a packet on a list. - */ -extern void skb_insert(struct sk_buff *old, struct sk_buff *newsk, struct sk_buff_head *list); -static inline void __skb_insert(struct sk_buff *newsk, - struct sk_buff *prev, struct sk_buff *next, - struct sk_buff_head *list) -{ - newsk->next = next; - newsk->prev = prev; - next->prev = prev->next = newsk; - list->qlen++; -} - -/* - * Place a packet after a given packet in a list. - */ -extern void skb_append(struct sk_buff *old, struct sk_buff *newsk, struct sk_buff_head *list); -static inline void __skb_append(struct sk_buff *old, struct sk_buff *newsk, struct sk_buff_head *list) -{ - __skb_insert(newsk, old, old->next, list); -} - -/* - * remove sk_buff from list. _Must_ be called atomically, and with - * the list known.. - */ -extern void skb_unlink(struct sk_buff *skb, struct sk_buff_head *list); -static inline void __skb_unlink(struct sk_buff *skb, struct sk_buff_head *list) -{ - struct sk_buff *next, *prev; - - list->qlen--; - next = skb->next; - prev = skb->prev; - skb->next = skb->prev = NULL; - next->prev = prev; - prev->next = next; -} - - -/* XXX: more streamlined implementation */ - -/** - * __skb_dequeue_tail - remove from the tail of the queue - * @list: list to dequeue from - * - * Remove the tail of the list. This function does not take any locks - * so must be used with appropriate locks held only. The tail item is - * returned or %NULL if the list is empty. - */ -extern struct sk_buff *skb_dequeue_tail(struct sk_buff_head *list); -static inline struct sk_buff *__skb_dequeue_tail(struct sk_buff_head *list) -{ - struct sk_buff *skb = skb_peek_tail(list); - if (skb) - __skb_unlink(skb, list); - return skb; -} - - -static inline int skb_is_nonlinear(const struct sk_buff *skb) -{ - return skb->data_len; -} - -static inline unsigned int skb_headlen(const struct sk_buff *skb) -{ - return skb->len - skb->data_len; -} - -static inline int skb_pagelen(const struct sk_buff *skb) -{ - int i, len = 0; - - for (i = (int)skb_shinfo(skb)->nr_frags - 1; i >= 0; i--) - len += skb_shinfo(skb)->frags[i].size; - return len + skb_headlen(skb); -} - -static inline void skb_fill_page_desc(struct sk_buff *skb, int i, - struct page *page, int off, int size) -{ - skb_frag_t *frag = &skb_shinfo(skb)->frags[i]; - - frag->page = page; - frag->page_offset = off; - frag->size = size; - skb_shinfo(skb)->nr_frags = i + 1; -} - -#define SKB_PAGE_ASSERT(skb) BUG_ON(skb_shinfo(skb)->nr_frags) -#define SKB_FRAG_ASSERT(skb) BUG_ON(skb_shinfo(skb)->frag_list) -#define SKB_LINEAR_ASSERT(skb) BUG_ON(skb_is_nonlinear(skb)) - -/* - * Add data to an sk_buff - */ -static inline unsigned char *__skb_put(struct sk_buff *skb, unsigned int len) -{ - unsigned char *tmp = skb->tail; - SKB_LINEAR_ASSERT(skb); - skb->tail += len; - skb->len += len; - return tmp; -} - -/** - * skb_put - add data to a buffer - * @skb: buffer to use - * @len: amount of data to add - * - * This function extends the used data area of the buffer. If this would - * exceed the total buffer size the kernel will panic. A pointer to the - * first byte of the extra data is returned. - */ -static inline unsigned char *skb_put(struct sk_buff *skb, unsigned int len) -{ - unsigned char *tmp = skb->tail; - SKB_LINEAR_ASSERT(skb); - skb->tail += len; - skb->len += len; - if (unlikely(skb->tail>skb->end)) - skb_over_panic(skb, len, current_text_addr()); - return tmp; -} - -static inline unsigned char *__skb_push(struct sk_buff *skb, unsigned int len) -{ - skb->data -= len; - skb->len += len; - return skb->data; -} - -/** - * skb_push - add data to the start of a buffer - * @skb: buffer to use - * @len: amount of data to add - * - * This function extends the used data area of the buffer at the buffer - * start. If this would exceed the total buffer headroom the kernel will - * panic. A pointer to the first byte of the extra data is returned. - */ -static inline unsigned char *skb_push(struct sk_buff *skb, unsigned int len) -{ - skb->data -= len; - skb->len += len; - if (unlikely(skb->data<skb->head)) - skb_under_panic(skb, len, current_text_addr()); - return skb->data; -} - -static inline unsigned char *__skb_pull(struct sk_buff *skb, unsigned int len) -{ - skb->len -= len; - BUG_ON(skb->len < skb->data_len); - return skb->data += len; -} - -/** - * skb_pull - remove data from the start of a buffer - * @skb: buffer to use - * @len: amount of data to remove - * - * This function removes data from the start of a buffer, returning - * the memory to the headroom. A pointer to the next data in the buffer - * is returned. Once the data has been pulled future pushes will overwrite - * the old data. - */ -static inline unsigned char *skb_pull(struct sk_buff *skb, unsigned int len) -{ - return unlikely(len > skb->len) ? NULL : __skb_pull(skb, len); -} - -extern unsigned char *__pskb_pull_tail(struct sk_buff *skb, int delta); - -static inline unsigned char *__pskb_pull(struct sk_buff *skb, unsigned int len) -{ - if (len > skb_headlen(skb) && - !__pskb_pull_tail(skb, len-skb_headlen(skb))) - return NULL; - skb->len -= len; - return skb->data += len; -} - -static inline unsigned char *pskb_pull(struct sk_buff *skb, unsigned int len) -{ - return unlikely(len > skb->len) ? NULL : __pskb_pull(skb, len); -} - -static inline int pskb_may_pull(struct sk_buff *skb, unsigned int len) -{ - if (likely(len <= skb_headlen(skb))) - return 1; - if (unlikely(len > skb->len)) - return 0; - return __pskb_pull_tail(skb, len-skb_headlen(skb)) != NULL; -} - -/** - * skb_headroom - bytes at buffer head - * @skb: buffer to check - * - * Return the number of bytes of free space at the head of an &sk_buff. - */ -static inline int skb_headroom(const struct sk_buff *skb) -{ - return skb->data - skb->head; -} - -/** - * skb_tailroom - bytes at buffer end - * @skb: buffer to check - * - * Return the number of bytes of free space at the tail of an sk_buff - */ -static inline int skb_tailroom(const struct sk_buff *skb) -{ - return skb_is_nonlinear(skb) ? 0 : skb->end - skb->tail; -} - -/** - * skb_reserve - adjust headroom - * @skb: buffer to alter - * @len: bytes to move - * - * Increase the headroom of an empty &sk_buff by reducing the tail - * room. This is only allowed for an empty buffer. - */ -static inline void skb_reserve(struct sk_buff *skb, int len) -{ - skb->data += len; - skb->tail += len; -} - -/* - * CPUs often take a performance hit when accessing unaligned memory - * locations. The actual performance hit varies, it can be small if the - * hardware handles it or large if we have to take an exception and fix it - * in software. - * - * Since an ethernet header is 14 bytes network drivers often end up with - * the IP header at an unaligned offset. The IP header can be aligned by - * shifting the start of the packet by 2 bytes. Drivers should do this - * with: - * - * skb_reserve(NET_IP_ALIGN); - * - * The downside to this alignment of the IP header is that the DMA is now - * unaligned. On some architectures the cost of an unaligned DMA is high - * and this cost outweighs the gains made by aligning the IP header. - * - * Since this trade off varies between architectures, we allow NET_IP_ALIGN - * to be overridden. - */ -#ifndef NET_IP_ALIGN -#define NET_IP_ALIGN 2 -#endif - -/* - * The networking layer reserves some headroom in skb data (via - * dev_alloc_skb). This is used to avoid having to reallocate skb data when - * the header has to grow. In the default case, if the header has to grow - * 16 bytes or less we avoid the reallocation. - * - * Unfortunately this headroom changes the DMA alignment of the resulting - * network packet. As for NET_IP_ALIGN, this unaligned DMA is expensive - * on some architectures. An architecture can override this value, - * perhaps setting it to a cacheline in size (since that will maintain - * cacheline alignment of the DMA). It must be a power of 2. - * - * Various parts of the networking layer expect at least 16 bytes of - * headroom, you should not reduce this. - */ -#ifndef NET_SKB_PAD -#define NET_SKB_PAD 16 -#endif - -extern int ___pskb_trim(struct sk_buff *skb, unsigned int len); - -static inline void __skb_trim(struct sk_buff *skb, unsigned int len) -{ - if (unlikely(skb->data_len)) { - WARN_ON(1); - return; - } - skb->len = len; - skb->tail = skb->data + len; -} - -/** - * 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. - * The skb must be linear. - */ -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) - return ___pskb_trim(skb, len); - __skb_trim(skb, len); - return 0; -} - -static inline int pskb_trim(struct sk_buff *skb, unsigned int len) -{ - return (len < skb->len) ? __pskb_trim(skb, len) : 0; -} - -/** - * pskb_trim_unique - remove end from a paged unique (not cloned) buffer - * @skb: buffer to alter - * @len: new length - * - * This is identical to pskb_trim except that the caller knows that - * the skb is not cloned so we should never get an error due to out- - * of-memory. - */ -static inline void pskb_trim_unique(struct sk_buff *skb, unsigned int len) -{ - int err = pskb_trim(skb, len); - BUG_ON(err); -} - -/** - * skb_orphan - orphan a buffer - * @skb: buffer to orphan - * - * If a buffer currently has an owner then we call the owner's - * destructor function and make the @skb unowned. The buffer continues - * to exist but is no longer charged to its former owner. - */ -static inline void skb_orphan(struct sk_buff *skb) -{ - if (skb->destructor) - skb->destructor(skb); - skb->destructor = NULL; - skb->sk = NULL; -} - -/** - * __skb_queue_purge - empty a list - * @list: list to empty - * - * Delete all buffers on an &sk_buff list. Each buffer is removed from - * the list and one reference dropped. This function does not take the - * list lock and the caller must hold the relevant locks to use it. - */ -extern void skb_queue_purge(struct sk_buff_head *list); -static inline void __skb_queue_purge(struct sk_buff_head *list) -{ - struct sk_buff *skb; - while ((skb = __skb_dequeue(list)) != NULL) - kfree_skb(skb); -} - -/** - * __dev_alloc_skb - allocate an skbuff for receiving - * @length: length to allocate - * @gfp_mask: get_free_pages mask, passed to alloc_skb - * - * Allocate a new &sk_buff and assign it a usage count of one. The - * buffer has unspecified headroom built in. Users should allocate - * the headroom they think they need without accounting for the - * built in space. The built in space is used for optimisations. - * - * %NULL is returned if there is no free memory. - */ -static inline struct sk_buff *__dev_alloc_skb(unsigned int length, - gfp_t gfp_mask) -{ - struct sk_buff *skb = alloc_skb(length + NET_SKB_PAD, gfp_mask); - if (likely(skb)) - skb_reserve(skb, NET_SKB_PAD); - return skb; -} - -/** - * dev_alloc_skb - allocate an skbuff for receiving - * @length: length to allocate - * - * Allocate a new &sk_buff and assign it a usage count of one. The - * buffer has unspecified headroom built in. Users should allocate - * the headroom they think they need without accounting for the - * built in space. The built in space is used for optimisations. - * - * %NULL is returned if there is no free memory. Although this function - * allocates memory it can be called from an interrupt. - */ -static inline struct sk_buff *dev_alloc_skb(unsigned int length) -{ - return __dev_alloc_skb(length, GFP_ATOMIC); -} - -extern struct sk_buff *__netdev_alloc_skb(struct net_device *dev, - unsigned int length, gfp_t gfp_mask); - -/** - * netdev_alloc_skb - allocate an skbuff for rx on a specific device - * @dev: network device to receive on - * @length: length to allocate - * - * Allocate a new &sk_buff and assign it a usage count of one. The - * buffer has unspecified headroom built in. Users should allocate - * the headroom they think they need without accounting for the - * built in space. The built in space is used for optimisations. - * - * %NULL is returned if there is no free memory. Although this function - * allocates memory it can be called from an interrupt. - */ -static inline struct sk_buff *netdev_alloc_skb(struct net_device *dev, - unsigned int length) -{ - return __netdev_alloc_skb(dev, length, GFP_ATOMIC); -} - -/** - * 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 > NET_SKB_PAD ? headroom : NET_SKB_PAD) - - skb_headroom(skb); - - if (delta < 0) - delta = 0; - - if (delta || skb_cloned(skb)) - return pskb_expand_head(skb, (delta + (NET_SKB_PAD-1)) & - ~(NET_SKB_PAD-1), 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. Otherwise it is extended. Returns zero on - * success. The skb is freed on error. - */ - -static inline int skb_padto(struct sk_buff *skb, unsigned int len) -{ - unsigned int size = skb->len; - if (likely(size >= len)) - return 0; - return skb_pad(skb, len-size); -} - -static inline int skb_add_data(struct sk_buff *skb, - char __user *from, int copy) -{ - const int off = skb->len; - - if (skb->ip_summed == CHECKSUM_NONE) { - int err = 0; - 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; -} - -static inline int __skb_linearize(struct sk_buff *skb) -{ - return __pskb_pull_tail(skb, skb->data_len) ? 0 : -ENOMEM; -} - -/** - * skb_linearize - convert paged skb to linear one - * @skb: buffer to linarize - * - * If there is no free memory -ENOMEM is returned, otherwise zero - * is returned and the old skb data released. - */ -static inline int skb_linearize(struct sk_buff *skb) -{ - return skb_is_nonlinear(skb) ? __skb_linearize(skb) : 0; -} - -/** - * skb_linearize_cow - make sure skb is linear and writable - * @skb: buffer to process - * - * If there is no free memory -ENOMEM is returned, otherwise zero - * is returned and the old skb data released. - */ -static inline int skb_linearize_cow(struct sk_buff *skb) -{ - return skb_is_nonlinear(skb) || skb_cloned(skb) ? - __skb_linearize(skb) : 0; -} - -/** - * skb_postpull_rcsum - update checksum for received skb after pull - * @skb: buffer to update - * @start: start of data before pull - * @len: length of data pulled - * - * After doing a pull on a received packet, you need to call this to - * update the CHECKSUM_HW checksum, or set ip_summed to CHECKSUM_NONE - * so that it can be recomputed from scratch. - */ - -static inline void skb_postpull_rcsum(struct sk_buff *skb, - const void *start, unsigned int len) -{ - if (skb->ip_summed == CHECKSUM_HW) - skb->csum = csum_sub(skb->csum, csum_partial(start, len, 0)); -} - -unsigned char *skb_pull_rcsum(struct sk_buff *skb, unsigned int len); - -/** - * pskb_trim_rcsum - trim received skb and update checksum - * @skb: buffer to trim - * @len: new length - * - * This is exactly the same as pskb_trim except that it ensures the - * checksum of received packets are still valid after the operation. - */ - -static inline int pskb_trim_rcsum(struct sk_buff *skb, unsigned int len) -{ - if (likely(len >= skb->len)) - return 0; - if (skb->ip_summed == CHECKSUM_HW) - skb->ip_summed = CHECKSUM_NONE; - return __pskb_trim(skb, len); -} - -static inline void *kmap_skb_frag(const skb_frag_t *frag) -{ -#ifdef CONFIG_HIGHMEM - BUG_ON(in_irq()); - - local_bh_disable(); -#endif - return kmap_atomic(frag->page, KM_SKB_DATA_SOFTIRQ); -} - -static inline void kunmap_skb_frag(void *vaddr) -{ - kunmap_atomic(vaddr, KM_SKB_DATA_SOFTIRQ); -#ifdef CONFIG_HIGHMEM - local_bh_enable(); -#endif -} - -#define skb_queue_walk(queue, skb) \ - for (skb = (queue)->next; \ - prefetch(skb->next), (skb != (struct sk_buff *)(queue)); \ - skb = skb->next) - -#define skb_queue_reverse_walk(queue, skb) \ - for (skb = (queue)->prev; \ - prefetch(skb->prev), (skb != (struct sk_buff *)(queue)); \ - skb = skb->prev) - - -extern struct sk_buff *skb_recv_datagram(struct sock *sk, unsigned flags, - int noblock, int *err); -extern unsigned int datagram_poll(struct file *file, struct socket *sock, - struct poll_table_struct *wait); -extern int skb_copy_datagram_iovec(const struct sk_buff *from, - int offset, struct iovec *to, - int size); -extern int skb_copy_and_csum_datagram_iovec(struct sk_buff *skb, - int hlen, - struct iovec *iov); -extern void skb_free_datagram(struct sock *sk, struct sk_buff *skb); -extern void skb_kill_datagram(struct sock *sk, struct sk_buff *skb, - unsigned int flags); -extern unsigned int skb_checksum(const struct sk_buff *skb, int offset, - int len, unsigned int csum); -extern int skb_copy_bits(const struct sk_buff *skb, int offset, - void *to, int len); -extern int skb_store_bits(const struct sk_buff *skb, int offset, - void *from, int len); -extern unsigned int skb_copy_and_csum_bits(const struct sk_buff *skb, - int offset, u8 *to, int len, - unsigned int csum); -extern void skb_copy_and_csum_dev(const struct sk_buff *skb, u8 *to); -extern void skb_split(struct sk_buff *skb, - struct sk_buff *skb1, const u32 len); - -extern struct sk_buff *skb_segment(struct sk_buff *skb, int features); - -static inline void *skb_header_pointer(const struct sk_buff *skb, int offset, - int len, void *buffer) -{ - int hlen = skb_headlen(skb); - - if (hlen - offset >= len) - return skb->data + offset; - - if (skb_copy_bits(skb, offset, buffer, len) < 0) - return NULL; - - return buffer; -} - -extern void skb_init(void); -extern void skb_add_mtu(int mtu); - -/** - * skb_get_timestamp - get timestamp from a skb - * @skb: skb to get stamp from - * @stamp: pointer to struct timeval to store stamp in - * - * Timestamps are stored in the skb as offsets to a base timestamp. - * This function converts the offset back to a struct timeval and stores - * it in stamp. - */ -static inline void skb_get_timestamp(const struct sk_buff *skb, struct timeval *stamp) -{ - stamp->tv_sec = skb->tstamp.off_sec; - stamp->tv_usec = skb->tstamp.off_usec; -} - -/** - * skb_set_timestamp - set timestamp of a skb - * @skb: skb to set stamp of - * @stamp: pointer to struct timeval to get stamp from - * - * Timestamps are stored in the skb as offsets to a base timestamp. - * This function converts a struct timeval to an offset and stores - * it in the skb. - */ -static inline void skb_set_timestamp(struct sk_buff *skb, const struct timeval *stamp) -{ - skb->tstamp.off_sec = stamp->tv_sec; - skb->tstamp.off_usec = stamp->tv_usec; -} - -extern void __net_timestamp(struct sk_buff *skb); - -extern unsigned int __skb_checksum_complete(struct sk_buff *skb); - -/** - * skb_checksum_complete - Calculate checksum of an entire packet - * @skb: packet to process - * - * This function calculates the checksum over the entire packet plus - * the value of skb->csum. The latter can be used to supply the - * checksum of a pseudo header as used by TCP/UDP. It returns the - * checksum. - * - * For protocols that contain complete checksums such as ICMP/TCP/UDP, - * this function can be used to verify that checksum on received - * packets. In that case the function should return zero if the - * checksum is correct. In particular, this function will return zero - * if skb->ip_summed is CHECKSUM_UNNECESSARY which indicates that the - * hardware has already verified the correctness of the checksum. - */ -static inline unsigned int skb_checksum_complete(struct sk_buff *skb) -{ - return skb->ip_summed != CHECKSUM_UNNECESSARY && - __skb_checksum_complete(skb); -} - -#ifdef CONFIG_NETFILTER -static inline void nf_conntrack_put(struct nf_conntrack *nfct) -{ - if (nfct && atomic_dec_and_test(&nfct->use)) - nfct->destroy(nfct); -} -static inline void nf_conntrack_get(struct nf_conntrack *nfct) -{ - if (nfct) - atomic_inc(&nfct->use); -} -#if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE) -static inline void nf_conntrack_get_reasm(struct sk_buff *skb) -{ - if (skb) - atomic_inc(&skb->users); -} -static inline void nf_conntrack_put_reasm(struct sk_buff *skb) -{ - if (skb) - kfree_skb(skb); -} -#endif -#ifdef CONFIG_BRIDGE_NETFILTER -static inline void nf_bridge_put(struct nf_bridge_info *nf_bridge) -{ - if (nf_bridge && atomic_dec_and_test(&nf_bridge->use)) - kfree(nf_bridge); -} -static inline void nf_bridge_get(struct nf_bridge_info *nf_bridge) -{ - if (nf_bridge) - atomic_inc(&nf_bridge->use); -} -#endif /* CONFIG_BRIDGE_NETFILTER */ -static inline void nf_reset(struct sk_buff *skb) -{ - nf_conntrack_put(skb->nfct); - skb->nfct = NULL; -#if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE) - nf_conntrack_put_reasm(skb->nfct_reasm); - skb->nfct_reasm = NULL; -#endif -#ifdef CONFIG_BRIDGE_NETFILTER - nf_bridge_put(skb->nf_bridge); - skb->nf_bridge = NULL; -#endif -} - -#else /* CONFIG_NETFILTER */ -static inline void nf_reset(struct sk_buff *skb) {} -#endif /* CONFIG_NETFILTER */ - -#ifdef CONFIG_NETWORK_SECMARK -static inline void skb_copy_secmark(struct sk_buff *to, const struct sk_buff *from) -{ - to->secmark = from->secmark; -} - -static inline void skb_init_secmark(struct sk_buff *skb) -{ - skb->secmark = 0; -} -#else -static inline void skb_copy_secmark(struct sk_buff *to, const struct sk_buff *from) -{ } - -static inline void skb_init_secmark(struct sk_buff *skb) -{ } -#endif - -static inline int skb_is_gso(const struct sk_buff *skb) -{ - return skb_shinfo(skb)->gso_size; -} - -#endif /* __KERNEL__ */ -#endif /* _LINUX_SKBUFF_H */ |