Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * Definitions for the 'struct sk_buff' memory handlers. |
| 3 | * |
| 4 | * Authors: |
| 5 | * Alan Cox, <gw4pts@gw4pts.ampr.org> |
| 6 | * Florian La Roche, <rzsfl@rz.uni-sb.de> |
| 7 | * |
| 8 | * This program is free software; you can redistribute it and/or |
| 9 | * modify it under the terms of the GNU General Public License |
| 10 | * as published by the Free Software Foundation; either version |
| 11 | * 2 of the License, or (at your option) any later version. |
| 12 | */ |
| 13 | |
| 14 | #ifndef _LINUX_SKBUFF_H |
| 15 | #define _LINUX_SKBUFF_H |
| 16 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 17 | #include <linux/kernel.h> |
| 18 | #include <linux/compiler.h> |
| 19 | #include <linux/time.h> |
| 20 | #include <linux/cache.h> |
| 21 | |
| 22 | #include <asm/atomic.h> |
| 23 | #include <asm/types.h> |
| 24 | #include <linux/spinlock.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 25 | #include <linux/net.h> |
Thomas Graf | 3fc7e8a | 2005-06-23 21:00:17 -0700 | [diff] [blame] | 26 | #include <linux/textsearch.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 27 | #include <net/checksum.h> |
Al Viro | a80958f | 2006-12-04 20:41:19 +0000 | [diff] [blame] | 28 | #include <linux/rcupdate.h> |
Chris Leech | 97fc2f0 | 2006-05-23 17:55:33 -0700 | [diff] [blame] | 29 | #include <linux/dmaengine.h> |
Eric Dumazet | b7aa0bf | 2007-04-19 16:16:32 -0700 | [diff] [blame] | 30 | #include <linux/hrtimer.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 31 | |
| 32 | #define HAVE_ALLOC_SKB /* For the drivers to know */ |
| 33 | #define HAVE_ALIGNABLE_SKB /* Ditto 8) */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 34 | |
Herbert Xu | 6047637 | 2007-04-09 11:59:39 -0700 | [diff] [blame] | 35 | /* Don't change this without changing skb_csum_unnecessary! */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 36 | #define CHECKSUM_NONE 0 |
Herbert Xu | 6047637 | 2007-04-09 11:59:39 -0700 | [diff] [blame] | 37 | #define CHECKSUM_UNNECESSARY 1 |
| 38 | #define CHECKSUM_COMPLETE 2 |
| 39 | #define CHECKSUM_PARTIAL 3 |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 40 | |
| 41 | #define SKB_DATA_ALIGN(X) (((X) + (SMP_CACHE_BYTES - 1)) & \ |
| 42 | ~(SMP_CACHE_BYTES - 1)) |
David S. Miller | fc910a2 | 2007-03-25 20:27:59 -0700 | [diff] [blame] | 43 | #define SKB_WITH_OVERHEAD(X) \ |
| 44 | (((X) - sizeof(struct skb_shared_info)) & \ |
| 45 | ~(SMP_CACHE_BYTES - 1)) |
| 46 | #define SKB_MAX_ORDER(X, ORDER) \ |
| 47 | SKB_WITH_OVERHEAD((PAGE_SIZE << (ORDER)) - (X)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 48 | #define SKB_MAX_HEAD(X) (SKB_MAX_ORDER((X), 0)) |
| 49 | #define SKB_MAX_ALLOC (SKB_MAX_ORDER(0, 2)) |
| 50 | |
| 51 | /* A. Checksumming of received packets by device. |
| 52 | * |
| 53 | * NONE: device failed to checksum this packet. |
| 54 | * skb->csum is undefined. |
| 55 | * |
| 56 | * UNNECESSARY: device parsed packet and wouldbe verified checksum. |
| 57 | * skb->csum is undefined. |
| 58 | * It is bad option, but, unfortunately, many of vendors do this. |
| 59 | * Apparently with secret goal to sell you new device, when you |
| 60 | * will add new protocol to your host. F.e. IPv6. 8) |
| 61 | * |
Patrick McHardy | 84fa793 | 2006-08-29 16:44:56 -0700 | [diff] [blame] | 62 | * COMPLETE: the most generic way. Device supplied checksum of _all_ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 63 | * the packet as seen by netif_rx in skb->csum. |
| 64 | * NOTE: Even if device supports only some protocols, but |
Patrick McHardy | 84fa793 | 2006-08-29 16:44:56 -0700 | [diff] [blame] | 65 | * is able to produce some skb->csum, it MUST use COMPLETE, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 66 | * not UNNECESSARY. |
| 67 | * |
| 68 | * B. Checksumming on output. |
| 69 | * |
| 70 | * NONE: skb is checksummed by protocol or csum is not required. |
| 71 | * |
Patrick McHardy | 84fa793 | 2006-08-29 16:44:56 -0700 | [diff] [blame] | 72 | * PARTIAL: device is required to csum packet as seen by hard_start_xmit |
Arnaldo Carvalho de Melo | b0e380b | 2007-04-10 21:21:55 -0700 | [diff] [blame] | 73 | * from skb->transport_header to the end and to record the checksum |
| 74 | * at skb->transport_header + skb->csum. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 75 | * |
| 76 | * Device must show its capabilities in dev->features, set |
| 77 | * at device setup time. |
| 78 | * NETIF_F_HW_CSUM - it is clever device, it is able to checksum |
| 79 | * everything. |
| 80 | * NETIF_F_NO_CSUM - loopback or reliable single hop media. |
| 81 | * NETIF_F_IP_CSUM - device is dumb. It is able to csum only |
| 82 | * TCP/UDP over IPv4. Sigh. Vendors like this |
| 83 | * way by an unknown reason. Though, see comment above |
| 84 | * about CHECKSUM_UNNECESSARY. 8) |
| 85 | * |
| 86 | * Any questions? No questions, good. --ANK |
| 87 | */ |
| 88 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 89 | struct net_device; |
David Howells | 716ea3a | 2007-04-02 20:19:53 -0700 | [diff] [blame] | 90 | struct scatterlist; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 91 | |
Yasuyuki Kozakai | 5f79e0f | 2007-03-23 11:17:07 -0700 | [diff] [blame] | 92 | #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 93 | struct nf_conntrack { |
| 94 | atomic_t use; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 95 | }; |
Yasuyuki Kozakai | 5f79e0f | 2007-03-23 11:17:07 -0700 | [diff] [blame] | 96 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 97 | |
| 98 | #ifdef CONFIG_BRIDGE_NETFILTER |
| 99 | struct nf_bridge_info { |
| 100 | atomic_t use; |
| 101 | struct net_device *physindev; |
| 102 | struct net_device *physoutdev; |
| 103 | #if defined(CONFIG_VLAN_8021Q) || defined(CONFIG_VLAN_8021Q_MODULE) |
| 104 | struct net_device *netoutdev; |
| 105 | #endif |
| 106 | unsigned int mask; |
| 107 | unsigned long data[32 / sizeof(unsigned long)]; |
| 108 | }; |
| 109 | #endif |
| 110 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 111 | struct sk_buff_head { |
| 112 | /* These two members must be first. */ |
| 113 | struct sk_buff *next; |
| 114 | struct sk_buff *prev; |
| 115 | |
| 116 | __u32 qlen; |
| 117 | spinlock_t lock; |
| 118 | }; |
| 119 | |
| 120 | struct sk_buff; |
| 121 | |
| 122 | /* To allow 64K frame to be packed as single skb without frag_list */ |
| 123 | #define MAX_SKB_FRAGS (65536/PAGE_SIZE + 2) |
| 124 | |
| 125 | typedef struct skb_frag_struct skb_frag_t; |
| 126 | |
| 127 | struct skb_frag_struct { |
| 128 | struct page *page; |
| 129 | __u16 page_offset; |
| 130 | __u16 size; |
| 131 | }; |
| 132 | |
| 133 | /* This data is invariant across clones and lives at |
| 134 | * the end of the header data, ie. at skb->end. |
| 135 | */ |
| 136 | struct skb_shared_info { |
| 137 | atomic_t dataref; |
Benjamin LaHaise | 4947d3e | 2006-01-03 14:06:50 -0800 | [diff] [blame] | 138 | unsigned short nr_frags; |
Herbert Xu | 7967168 | 2006-06-22 02:40:14 -0700 | [diff] [blame] | 139 | unsigned short gso_size; |
| 140 | /* Warning: this field is not always filled in (UFO)! */ |
| 141 | unsigned short gso_segs; |
| 142 | unsigned short gso_type; |
Al Viro | ae08e1f | 2006-11-08 00:27:11 -0800 | [diff] [blame] | 143 | __be32 ip6_frag_id; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 144 | struct sk_buff *frag_list; |
| 145 | skb_frag_t frags[MAX_SKB_FRAGS]; |
| 146 | }; |
| 147 | |
| 148 | /* We divide dataref into two halves. The higher 16 bits hold references |
| 149 | * to the payload part of skb->data. The lower 16 bits hold references to |
| 150 | * the entire skb->data. It is up to the users of the skb to agree on |
| 151 | * where the payload starts. |
| 152 | * |
| 153 | * All users must obey the rule that the skb->data reference count must be |
| 154 | * greater than or equal to the payload reference count. |
| 155 | * |
| 156 | * Holding a reference to the payload part means that the user does not |
| 157 | * care about modifications to the header part of skb->data. |
| 158 | */ |
| 159 | #define SKB_DATAREF_SHIFT 16 |
| 160 | #define SKB_DATAREF_MASK ((1 << SKB_DATAREF_SHIFT) - 1) |
| 161 | |
David S. Miller | d179cd1 | 2005-08-17 14:57:30 -0700 | [diff] [blame] | 162 | |
| 163 | enum { |
| 164 | SKB_FCLONE_UNAVAILABLE, |
| 165 | SKB_FCLONE_ORIG, |
| 166 | SKB_FCLONE_CLONE, |
| 167 | }; |
| 168 | |
Herbert Xu | 7967168 | 2006-06-22 02:40:14 -0700 | [diff] [blame] | 169 | enum { |
| 170 | SKB_GSO_TCPV4 = 1 << 0, |
Herbert Xu | f83ef8c | 2006-06-30 13:37:03 -0700 | [diff] [blame] | 171 | SKB_GSO_UDP = 1 << 1, |
Herbert Xu | 576a30e | 2006-06-27 13:22:38 -0700 | [diff] [blame] | 172 | |
| 173 | /* This indicates the skb is from an untrusted source. */ |
| 174 | SKB_GSO_DODGY = 1 << 2, |
Michael Chan | b0da8537 | 2006-06-29 12:30:00 -0700 | [diff] [blame] | 175 | |
| 176 | /* This indicates the tcp segment has CWR set. */ |
Herbert Xu | f83ef8c | 2006-06-30 13:37:03 -0700 | [diff] [blame] | 177 | SKB_GSO_TCP_ECN = 1 << 3, |
| 178 | |
| 179 | SKB_GSO_TCPV6 = 1 << 4, |
Herbert Xu | 7967168 | 2006-06-22 02:40:14 -0700 | [diff] [blame] | 180 | }; |
| 181 | |
Arnaldo Carvalho de Melo | 2e07fa9 | 2007-04-10 21:22:35 -0700 | [diff] [blame] | 182 | #if BITS_PER_LONG > 32 |
| 183 | #define NET_SKBUFF_DATA_USES_OFFSET 1 |
| 184 | #endif |
| 185 | |
| 186 | #ifdef NET_SKBUFF_DATA_USES_OFFSET |
| 187 | typedef unsigned int sk_buff_data_t; |
| 188 | #else |
| 189 | typedef unsigned char *sk_buff_data_t; |
| 190 | #endif |
| 191 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 192 | /** |
| 193 | * struct sk_buff - socket buffer |
| 194 | * @next: Next buffer in list |
| 195 | * @prev: Previous buffer in list |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 196 | * @sk: Socket we are owned by |
Herbert Xu | 325ed82 | 2005-10-03 13:57:23 -0700 | [diff] [blame] | 197 | * @tstamp: Time we arrived |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 198 | * @dev: Device we arrived on/are leaving by |
Patrick McHardy | c01003c | 2007-03-29 11:46:52 -0700 | [diff] [blame] | 199 | * @iif: ifindex of device we arrived on |
Randy Dunlap | be52178 | 2007-05-03 03:16:20 -0700 | [diff] [blame] | 200 | * @transport_header: Transport layer header |
Arnaldo Carvalho de Melo | b0e380b | 2007-04-10 21:21:55 -0700 | [diff] [blame] | 201 | * @network_header: Network layer header |
| 202 | * @mac_header: Link layer header |
Martin Waitz | 67be2dd | 2005-05-01 08:59:26 -0700 | [diff] [blame] | 203 | * @dst: destination entry |
| 204 | * @sp: the security path, used for xfrm |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 205 | * @cb: Control buffer. Free for use by every layer. Put private vars here |
| 206 | * @len: Length of actual data |
| 207 | * @data_len: Data length |
| 208 | * @mac_len: Length of link layer header |
Herbert Xu | 663ead3 | 2007-04-09 11:59:07 -0700 | [diff] [blame] | 209 | * @csum: Checksum (must include start/offset pair) |
| 210 | * @csum_start: Offset from skb->head where checksumming should start |
| 211 | * @csum_offset: Offset from csum_start where checksum should be stored |
Martin Waitz | 67be2dd | 2005-05-01 08:59:26 -0700 | [diff] [blame] | 212 | * @local_df: allow local fragmentation |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 213 | * @cloned: Head may be cloned (check refcnt to be sure) |
| 214 | * @nohdr: Payload reference only, must not modify header |
| 215 | * @pkt_type: Packet class |
Randy Dunlap | c83c248 | 2005-10-18 22:07:41 -0700 | [diff] [blame] | 216 | * @fclone: skbuff clone status |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 217 | * @ip_summed: Driver fed us an IP checksum |
| 218 | * @priority: Packet queueing priority |
| 219 | * @users: User count - see {datagram,tcp}.c |
| 220 | * @protocol: Packet protocol from driver |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 221 | * @truesize: Buffer size |
| 222 | * @head: Head of buffer |
| 223 | * @data: Data head pointer |
| 224 | * @tail: Tail pointer |
| 225 | * @end: End pointer |
| 226 | * @destructor: Destruct function |
Thomas Graf | 82e91ff | 2006-11-09 15:19:14 -0800 | [diff] [blame] | 227 | * @mark: Generic packet mark |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 228 | * @nfct: Associated connection, if any |
Randy Dunlap | c83c248 | 2005-10-18 22:07:41 -0700 | [diff] [blame] | 229 | * @ipvs_property: skbuff is owned by ipvs |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 230 | * @nfctinfo: Relationship of this skb to the connection |
Randy Dunlap | 461ddf3 | 2005-11-20 21:25:15 -0800 | [diff] [blame] | 231 | * @nfct_reasm: netfilter conntrack re-assembly pointer |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 232 | * @nf_bridge: Saved data about a bridged frame - see br_netfilter.c |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 233 | * @tc_index: Traffic control index |
| 234 | * @tc_verd: traffic control verdict |
Randy Dunlap | f4b8ea7 | 2006-06-22 16:00:11 -0700 | [diff] [blame] | 235 | * @dma_cookie: a cookie to one of several possible DMA operations |
| 236 | * done by skb DMA functions |
James Morris | 984bc16 | 2006-06-09 00:29:17 -0700 | [diff] [blame] | 237 | * @secmark: security marking |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 238 | */ |
| 239 | |
| 240 | struct sk_buff { |
| 241 | /* These two members must be first. */ |
| 242 | struct sk_buff *next; |
| 243 | struct sk_buff *prev; |
| 244 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 245 | struct sock *sk; |
Eric Dumazet | b7aa0bf | 2007-04-19 16:16:32 -0700 | [diff] [blame] | 246 | ktime_t tstamp; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 247 | struct net_device *dev; |
Patrick McHardy | c01003c | 2007-03-29 11:46:52 -0700 | [diff] [blame] | 248 | int iif; |
| 249 | /* 4 byte hole on 64 bit*/ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 250 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 251 | struct dst_entry *dst; |
| 252 | struct sec_path *sp; |
| 253 | |
| 254 | /* |
| 255 | * This is the control buffer. It is free to use for every |
| 256 | * layer. Please put your private variables there. If you |
| 257 | * want to keep them across layers you have to do a skb_clone() |
| 258 | * first. This is owned by whoever has the skb queued ATM. |
| 259 | */ |
Patrick McHardy | 3e3850e | 2006-01-06 23:04:54 -0800 | [diff] [blame] | 260 | char cb[48]; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 261 | |
| 262 | unsigned int len, |
| 263 | data_len, |
Al Viro | 1f61ab5 | 2006-11-14 21:44:08 -0800 | [diff] [blame] | 264 | mac_len; |
Al Viro | ff1dcad | 2006-11-20 18:07:29 -0800 | [diff] [blame] | 265 | union { |
| 266 | __wsum csum; |
Herbert Xu | 663ead3 | 2007-04-09 11:59:07 -0700 | [diff] [blame] | 267 | struct { |
| 268 | __u16 csum_start; |
| 269 | __u16 csum_offset; |
| 270 | }; |
Al Viro | ff1dcad | 2006-11-20 18:07:29 -0800 | [diff] [blame] | 271 | }; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 272 | __u32 priority; |
Thomas Graf | 1cbb338 | 2005-07-05 14:13:41 -0700 | [diff] [blame] | 273 | __u8 local_df:1, |
| 274 | cloned:1, |
| 275 | ip_summed:2, |
Harald Welte | 6869c4d | 2005-08-09 19:24:19 -0700 | [diff] [blame] | 276 | nohdr:1, |
| 277 | nfctinfo:3; |
David S. Miller | d179cd1 | 2005-08-17 14:57:30 -0700 | [diff] [blame] | 278 | __u8 pkt_type:3, |
Patrick McHardy | b84f4cc | 2005-11-20 21:19:21 -0800 | [diff] [blame] | 279 | fclone:2, |
| 280 | ipvs_property:1; |
Alexey Dobriyan | a0d3bea | 2005-08-11 16:05:50 -0700 | [diff] [blame] | 281 | __be16 protocol; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 282 | |
| 283 | void (*destructor)(struct sk_buff *skb); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 284 | #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE) |
Yasuyuki Kozakai | 5f79e0f | 2007-03-23 11:17:07 -0700 | [diff] [blame] | 285 | struct nf_conntrack *nfct; |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 286 | struct sk_buff *nfct_reasm; |
| 287 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 288 | #ifdef CONFIG_BRIDGE_NETFILTER |
| 289 | struct nf_bridge_info *nf_bridge; |
| 290 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 291 | #ifdef CONFIG_NET_SCHED |
Patrick McHardy | b6b99eb | 2005-08-09 19:33:51 -0700 | [diff] [blame] | 292 | __u16 tc_index; /* traffic control index */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 293 | #ifdef CONFIG_NET_CLS_ACT |
Patrick McHardy | b6b99eb | 2005-08-09 19:33:51 -0700 | [diff] [blame] | 294 | __u16 tc_verd; /* traffic control verdict */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 295 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 296 | #endif |
Chris Leech | 97fc2f0 | 2006-05-23 17:55:33 -0700 | [diff] [blame] | 297 | #ifdef CONFIG_NET_DMA |
| 298 | dma_cookie_t dma_cookie; |
| 299 | #endif |
James Morris | 984bc16 | 2006-06-09 00:29:17 -0700 | [diff] [blame] | 300 | #ifdef CONFIG_NETWORK_SECMARK |
| 301 | __u32 secmark; |
| 302 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 303 | |
Thomas Graf | 82e91ff | 2006-11-09 15:19:14 -0800 | [diff] [blame] | 304 | __u32 mark; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 305 | |
Arnaldo Carvalho de Melo | 27a884d | 2007-04-19 20:29:13 -0700 | [diff] [blame] | 306 | sk_buff_data_t transport_header; |
| 307 | sk_buff_data_t network_header; |
| 308 | sk_buff_data_t mac_header; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 309 | /* These elements must be at the end, see alloc_skb() for details. */ |
Arnaldo Carvalho de Melo | 27a884d | 2007-04-19 20:29:13 -0700 | [diff] [blame] | 310 | sk_buff_data_t tail; |
Arnaldo Carvalho de Melo | 4305b54 | 2007-04-19 20:43:29 -0700 | [diff] [blame] | 311 | sk_buff_data_t end; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 312 | unsigned char *head, |
Arnaldo Carvalho de Melo | 4305b54 | 2007-04-19 20:43:29 -0700 | [diff] [blame] | 313 | *data; |
Arnaldo Carvalho de Melo | 27a884d | 2007-04-19 20:29:13 -0700 | [diff] [blame] | 314 | unsigned int truesize; |
| 315 | atomic_t users; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 316 | }; |
| 317 | |
| 318 | #ifdef __KERNEL__ |
| 319 | /* |
| 320 | * Handling routines are only of interest to the kernel |
| 321 | */ |
| 322 | #include <linux/slab.h> |
| 323 | |
| 324 | #include <asm/system.h> |
| 325 | |
Jörn Engel | 231d06a | 2006-03-20 21:28:35 -0800 | [diff] [blame] | 326 | extern void kfree_skb(struct sk_buff *skb); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 327 | extern void __kfree_skb(struct sk_buff *skb); |
David S. Miller | d179cd1 | 2005-08-17 14:57:30 -0700 | [diff] [blame] | 328 | extern struct sk_buff *__alloc_skb(unsigned int size, |
Christoph Hellwig | b30973f | 2006-12-06 20:32:36 -0800 | [diff] [blame] | 329 | gfp_t priority, int fclone, int node); |
David S. Miller | d179cd1 | 2005-08-17 14:57:30 -0700 | [diff] [blame] | 330 | static inline struct sk_buff *alloc_skb(unsigned int size, |
Al Viro | dd0fc66 | 2005-10-07 07:46:04 +0100 | [diff] [blame] | 331 | gfp_t priority) |
David S. Miller | d179cd1 | 2005-08-17 14:57:30 -0700 | [diff] [blame] | 332 | { |
Christoph Hellwig | b30973f | 2006-12-06 20:32:36 -0800 | [diff] [blame] | 333 | return __alloc_skb(size, priority, 0, -1); |
David S. Miller | d179cd1 | 2005-08-17 14:57:30 -0700 | [diff] [blame] | 334 | } |
| 335 | |
| 336 | static inline struct sk_buff *alloc_skb_fclone(unsigned int size, |
Al Viro | dd0fc66 | 2005-10-07 07:46:04 +0100 | [diff] [blame] | 337 | gfp_t priority) |
David S. Miller | d179cd1 | 2005-08-17 14:57:30 -0700 | [diff] [blame] | 338 | { |
Christoph Hellwig | b30973f | 2006-12-06 20:32:36 -0800 | [diff] [blame] | 339 | return __alloc_skb(size, priority, 1, -1); |
David S. Miller | d179cd1 | 2005-08-17 14:57:30 -0700 | [diff] [blame] | 340 | } |
| 341 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 342 | extern void kfree_skbmem(struct sk_buff *skb); |
Victor Fusco | 86a76ca | 2005-07-08 14:57:47 -0700 | [diff] [blame] | 343 | extern struct sk_buff *skb_clone(struct sk_buff *skb, |
Al Viro | dd0fc66 | 2005-10-07 07:46:04 +0100 | [diff] [blame] | 344 | gfp_t priority); |
Victor Fusco | 86a76ca | 2005-07-08 14:57:47 -0700 | [diff] [blame] | 345 | extern struct sk_buff *skb_copy(const struct sk_buff *skb, |
Al Viro | dd0fc66 | 2005-10-07 07:46:04 +0100 | [diff] [blame] | 346 | gfp_t priority); |
Victor Fusco | 86a76ca | 2005-07-08 14:57:47 -0700 | [diff] [blame] | 347 | extern struct sk_buff *pskb_copy(struct sk_buff *skb, |
Al Viro | dd0fc66 | 2005-10-07 07:46:04 +0100 | [diff] [blame] | 348 | gfp_t gfp_mask); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 349 | extern int pskb_expand_head(struct sk_buff *skb, |
Victor Fusco | 86a76ca | 2005-07-08 14:57:47 -0700 | [diff] [blame] | 350 | int nhead, int ntail, |
Al Viro | dd0fc66 | 2005-10-07 07:46:04 +0100 | [diff] [blame] | 351 | gfp_t gfp_mask); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 352 | extern struct sk_buff *skb_realloc_headroom(struct sk_buff *skb, |
| 353 | unsigned int headroom); |
| 354 | extern struct sk_buff *skb_copy_expand(const struct sk_buff *skb, |
| 355 | int newheadroom, int newtailroom, |
Al Viro | dd0fc66 | 2005-10-07 07:46:04 +0100 | [diff] [blame] | 356 | gfp_t priority); |
David Howells | 716ea3a | 2007-04-02 20:19:53 -0700 | [diff] [blame] | 357 | extern int skb_to_sgvec(struct sk_buff *skb, |
| 358 | struct scatterlist *sg, int offset, |
| 359 | int len); |
| 360 | extern int skb_cow_data(struct sk_buff *skb, int tailbits, |
| 361 | struct sk_buff **trailer); |
Herbert Xu | 5b057c6 | 2006-06-23 02:06:41 -0700 | [diff] [blame] | 362 | extern int skb_pad(struct sk_buff *skb, int pad); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 363 | #define dev_kfree_skb(a) kfree_skb(a) |
| 364 | extern void skb_over_panic(struct sk_buff *skb, int len, |
| 365 | void *here); |
| 366 | extern void skb_under_panic(struct sk_buff *skb, int len, |
| 367 | void *here); |
David S. Miller | dc6de33 | 2006-04-20 00:10:50 -0700 | [diff] [blame] | 368 | extern void skb_truesize_bug(struct sk_buff *skb); |
| 369 | |
| 370 | static inline void skb_truesize_check(struct sk_buff *skb) |
| 371 | { |
| 372 | if (unlikely((int)skb->truesize < sizeof(struct sk_buff) + skb->len)) |
| 373 | skb_truesize_bug(skb); |
| 374 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 375 | |
Ananda Raju | e89e9cf | 2005-10-18 15:46:41 -0700 | [diff] [blame] | 376 | extern int skb_append_datato_frags(struct sock *sk, struct sk_buff *skb, |
| 377 | int getfrag(void *from, char *to, int offset, |
| 378 | int len,int odd, struct sk_buff *skb), |
| 379 | void *from, int length); |
| 380 | |
Thomas Graf | 677e90e | 2005-06-23 20:59:51 -0700 | [diff] [blame] | 381 | struct skb_seq_state |
| 382 | { |
| 383 | __u32 lower_offset; |
| 384 | __u32 upper_offset; |
| 385 | __u32 frag_idx; |
| 386 | __u32 stepped_offset; |
| 387 | struct sk_buff *root_skb; |
| 388 | struct sk_buff *cur_skb; |
| 389 | __u8 *frag_data; |
| 390 | }; |
| 391 | |
| 392 | extern void skb_prepare_seq_read(struct sk_buff *skb, |
| 393 | unsigned int from, unsigned int to, |
| 394 | struct skb_seq_state *st); |
| 395 | extern unsigned int skb_seq_read(unsigned int consumed, const u8 **data, |
| 396 | struct skb_seq_state *st); |
| 397 | extern void skb_abort_seq_read(struct skb_seq_state *st); |
| 398 | |
Thomas Graf | 3fc7e8a | 2005-06-23 21:00:17 -0700 | [diff] [blame] | 399 | extern unsigned int skb_find_text(struct sk_buff *skb, unsigned int from, |
| 400 | unsigned int to, struct ts_config *config, |
| 401 | struct ts_state *state); |
| 402 | |
Arnaldo Carvalho de Melo | 4305b54 | 2007-04-19 20:43:29 -0700 | [diff] [blame] | 403 | #ifdef NET_SKBUFF_DATA_USES_OFFSET |
| 404 | static inline unsigned char *skb_end_pointer(const struct sk_buff *skb) |
| 405 | { |
| 406 | return skb->head + skb->end; |
| 407 | } |
| 408 | #else |
| 409 | static inline unsigned char *skb_end_pointer(const struct sk_buff *skb) |
| 410 | { |
| 411 | return skb->end; |
| 412 | } |
| 413 | #endif |
| 414 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 415 | /* Internal */ |
Arnaldo Carvalho de Melo | 4305b54 | 2007-04-19 20:43:29 -0700 | [diff] [blame] | 416 | #define skb_shinfo(SKB) ((struct skb_shared_info *)(skb_end_pointer(SKB))) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 417 | |
| 418 | /** |
| 419 | * skb_queue_empty - check if a queue is empty |
| 420 | * @list: queue head |
| 421 | * |
| 422 | * Returns true if the queue is empty, false otherwise. |
| 423 | */ |
| 424 | static inline int skb_queue_empty(const struct sk_buff_head *list) |
| 425 | { |
| 426 | return list->next == (struct sk_buff *)list; |
| 427 | } |
| 428 | |
| 429 | /** |
| 430 | * skb_get - reference buffer |
| 431 | * @skb: buffer to reference |
| 432 | * |
| 433 | * Makes another reference to a socket buffer and returns a pointer |
| 434 | * to the buffer. |
| 435 | */ |
| 436 | static inline struct sk_buff *skb_get(struct sk_buff *skb) |
| 437 | { |
| 438 | atomic_inc(&skb->users); |
| 439 | return skb; |
| 440 | } |
| 441 | |
| 442 | /* |
| 443 | * If users == 1, we are the only owner and are can avoid redundant |
| 444 | * atomic change. |
| 445 | */ |
| 446 | |
| 447 | /** |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 448 | * skb_cloned - is the buffer a clone |
| 449 | * @skb: buffer to check |
| 450 | * |
| 451 | * Returns true if the buffer was generated with skb_clone() and is |
| 452 | * one of multiple shared copies of the buffer. Cloned buffers are |
| 453 | * shared data so must not be written to under normal circumstances. |
| 454 | */ |
| 455 | static inline int skb_cloned(const struct sk_buff *skb) |
| 456 | { |
| 457 | return skb->cloned && |
| 458 | (atomic_read(&skb_shinfo(skb)->dataref) & SKB_DATAREF_MASK) != 1; |
| 459 | } |
| 460 | |
| 461 | /** |
| 462 | * skb_header_cloned - is the header a clone |
| 463 | * @skb: buffer to check |
| 464 | * |
| 465 | * Returns true if modifying the header part of the buffer requires |
| 466 | * the data to be copied. |
| 467 | */ |
| 468 | static inline int skb_header_cloned(const struct sk_buff *skb) |
| 469 | { |
| 470 | int dataref; |
| 471 | |
| 472 | if (!skb->cloned) |
| 473 | return 0; |
| 474 | |
| 475 | dataref = atomic_read(&skb_shinfo(skb)->dataref); |
| 476 | dataref = (dataref & SKB_DATAREF_MASK) - (dataref >> SKB_DATAREF_SHIFT); |
| 477 | return dataref != 1; |
| 478 | } |
| 479 | |
| 480 | /** |
| 481 | * skb_header_release - release reference to header |
| 482 | * @skb: buffer to operate on |
| 483 | * |
| 484 | * Drop a reference to the header part of the buffer. This is done |
| 485 | * by acquiring a payload reference. You must not read from the header |
| 486 | * part of skb->data after this. |
| 487 | */ |
| 488 | static inline void skb_header_release(struct sk_buff *skb) |
| 489 | { |
| 490 | BUG_ON(skb->nohdr); |
| 491 | skb->nohdr = 1; |
| 492 | atomic_add(1 << SKB_DATAREF_SHIFT, &skb_shinfo(skb)->dataref); |
| 493 | } |
| 494 | |
| 495 | /** |
| 496 | * skb_shared - is the buffer shared |
| 497 | * @skb: buffer to check |
| 498 | * |
| 499 | * Returns true if more than one person has a reference to this |
| 500 | * buffer. |
| 501 | */ |
| 502 | static inline int skb_shared(const struct sk_buff *skb) |
| 503 | { |
| 504 | return atomic_read(&skb->users) != 1; |
| 505 | } |
| 506 | |
| 507 | /** |
| 508 | * skb_share_check - check if buffer is shared and if so clone it |
| 509 | * @skb: buffer to check |
| 510 | * @pri: priority for memory allocation |
| 511 | * |
| 512 | * If the buffer is shared the buffer is cloned and the old copy |
| 513 | * drops a reference. A new clone with a single reference is returned. |
| 514 | * If the buffer is not shared the original buffer is returned. When |
| 515 | * being called from interrupt status or with spinlocks held pri must |
| 516 | * be GFP_ATOMIC. |
| 517 | * |
| 518 | * NULL is returned on a memory allocation failure. |
| 519 | */ |
Victor Fusco | 86a76ca | 2005-07-08 14:57:47 -0700 | [diff] [blame] | 520 | static inline struct sk_buff *skb_share_check(struct sk_buff *skb, |
Al Viro | dd0fc66 | 2005-10-07 07:46:04 +0100 | [diff] [blame] | 521 | gfp_t pri) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 522 | { |
| 523 | might_sleep_if(pri & __GFP_WAIT); |
| 524 | if (skb_shared(skb)) { |
| 525 | struct sk_buff *nskb = skb_clone(skb, pri); |
| 526 | kfree_skb(skb); |
| 527 | skb = nskb; |
| 528 | } |
| 529 | return skb; |
| 530 | } |
| 531 | |
| 532 | /* |
| 533 | * Copy shared buffers into a new sk_buff. We effectively do COW on |
| 534 | * packets to handle cases where we have a local reader and forward |
| 535 | * and a couple of other messy ones. The normal one is tcpdumping |
| 536 | * a packet thats being forwarded. |
| 537 | */ |
| 538 | |
| 539 | /** |
| 540 | * skb_unshare - make a copy of a shared buffer |
| 541 | * @skb: buffer to check |
| 542 | * @pri: priority for memory allocation |
| 543 | * |
| 544 | * If the socket buffer is a clone then this function creates a new |
| 545 | * copy of the data, drops a reference count on the old copy and returns |
| 546 | * the new copy with the reference count at 1. If the buffer is not a clone |
| 547 | * the original buffer is returned. When called with a spinlock held or |
| 548 | * from interrupt state @pri must be %GFP_ATOMIC |
| 549 | * |
| 550 | * %NULL is returned on a memory allocation failure. |
| 551 | */ |
Victor Fusco | e2bf521 | 2005-07-18 13:36:38 -0700 | [diff] [blame] | 552 | static inline struct sk_buff *skb_unshare(struct sk_buff *skb, |
Al Viro | dd0fc66 | 2005-10-07 07:46:04 +0100 | [diff] [blame] | 553 | gfp_t pri) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 554 | { |
| 555 | might_sleep_if(pri & __GFP_WAIT); |
| 556 | if (skb_cloned(skb)) { |
| 557 | struct sk_buff *nskb = skb_copy(skb, pri); |
| 558 | kfree_skb(skb); /* Free our shared copy */ |
| 559 | skb = nskb; |
| 560 | } |
| 561 | return skb; |
| 562 | } |
| 563 | |
| 564 | /** |
| 565 | * skb_peek |
| 566 | * @list_: list to peek at |
| 567 | * |
| 568 | * Peek an &sk_buff. Unlike most other operations you _MUST_ |
| 569 | * be careful with this one. A peek leaves the buffer on the |
| 570 | * list and someone else may run off with it. You must hold |
| 571 | * the appropriate locks or have a private queue to do this. |
| 572 | * |
| 573 | * Returns %NULL for an empty list or a pointer to the head element. |
| 574 | * The reference count is not incremented and the reference is therefore |
| 575 | * volatile. Use with caution. |
| 576 | */ |
| 577 | static inline struct sk_buff *skb_peek(struct sk_buff_head *list_) |
| 578 | { |
| 579 | struct sk_buff *list = ((struct sk_buff *)list_)->next; |
| 580 | if (list == (struct sk_buff *)list_) |
| 581 | list = NULL; |
| 582 | return list; |
| 583 | } |
| 584 | |
| 585 | /** |
| 586 | * skb_peek_tail |
| 587 | * @list_: list to peek at |
| 588 | * |
| 589 | * Peek an &sk_buff. Unlike most other operations you _MUST_ |
| 590 | * be careful with this one. A peek leaves the buffer on the |
| 591 | * list and someone else may run off with it. You must hold |
| 592 | * the appropriate locks or have a private queue to do this. |
| 593 | * |
| 594 | * Returns %NULL for an empty list or a pointer to the tail element. |
| 595 | * The reference count is not incremented and the reference is therefore |
| 596 | * volatile. Use with caution. |
| 597 | */ |
| 598 | static inline struct sk_buff *skb_peek_tail(struct sk_buff_head *list_) |
| 599 | { |
| 600 | struct sk_buff *list = ((struct sk_buff *)list_)->prev; |
| 601 | if (list == (struct sk_buff *)list_) |
| 602 | list = NULL; |
| 603 | return list; |
| 604 | } |
| 605 | |
| 606 | /** |
| 607 | * skb_queue_len - get queue length |
| 608 | * @list_: list to measure |
| 609 | * |
| 610 | * Return the length of an &sk_buff queue. |
| 611 | */ |
| 612 | static inline __u32 skb_queue_len(const struct sk_buff_head *list_) |
| 613 | { |
| 614 | return list_->qlen; |
| 615 | } |
| 616 | |
Arjan van de Ven | 76f10ad | 2006-08-02 14:06:55 -0700 | [diff] [blame] | 617 | /* |
| 618 | * This function creates a split out lock class for each invocation; |
| 619 | * this is needed for now since a whole lot of users of the skb-queue |
| 620 | * infrastructure in drivers have different locking usage (in hardirq) |
| 621 | * than the networking core (in softirq only). In the long run either the |
| 622 | * network layer or drivers should need annotation to consolidate the |
| 623 | * main types of usage into 3 classes. |
| 624 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 625 | static inline void skb_queue_head_init(struct sk_buff_head *list) |
| 626 | { |
| 627 | spin_lock_init(&list->lock); |
| 628 | list->prev = list->next = (struct sk_buff *)list; |
| 629 | list->qlen = 0; |
| 630 | } |
| 631 | |
Pavel Emelianov | c2ecba7 | 2007-04-17 12:45:31 -0700 | [diff] [blame] | 632 | static inline void skb_queue_head_init_class(struct sk_buff_head *list, |
| 633 | struct lock_class_key *class) |
| 634 | { |
| 635 | skb_queue_head_init(list); |
| 636 | lockdep_set_class(&list->lock, class); |
| 637 | } |
| 638 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 639 | /* |
| 640 | * Insert an sk_buff at the start of a list. |
| 641 | * |
| 642 | * The "__skb_xxxx()" functions are the non-atomic ones that |
| 643 | * can only be called with interrupts disabled. |
| 644 | */ |
| 645 | |
| 646 | /** |
Stephen Hemminger | 300ce17 | 2005-10-30 13:47:34 -0800 | [diff] [blame] | 647 | * __skb_queue_after - queue a buffer at the list head |
| 648 | * @list: list to use |
| 649 | * @prev: place after this buffer |
| 650 | * @newsk: buffer to queue |
| 651 | * |
| 652 | * Queue a buffer int the middle of a list. This function takes no locks |
| 653 | * and you must therefore hold required locks before calling it. |
| 654 | * |
| 655 | * A buffer cannot be placed on two lists at the same time. |
| 656 | */ |
| 657 | static inline void __skb_queue_after(struct sk_buff_head *list, |
| 658 | struct sk_buff *prev, |
| 659 | struct sk_buff *newsk) |
| 660 | { |
| 661 | struct sk_buff *next; |
| 662 | list->qlen++; |
| 663 | |
| 664 | next = prev->next; |
| 665 | newsk->next = next; |
| 666 | newsk->prev = prev; |
| 667 | next->prev = prev->next = newsk; |
| 668 | } |
| 669 | |
| 670 | /** |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 671 | * __skb_queue_head - queue a buffer at the list head |
| 672 | * @list: list to use |
| 673 | * @newsk: buffer to queue |
| 674 | * |
| 675 | * Queue a buffer at the start of a list. This function takes no locks |
| 676 | * and you must therefore hold required locks before calling it. |
| 677 | * |
| 678 | * A buffer cannot be placed on two lists at the same time. |
| 679 | */ |
| 680 | extern void skb_queue_head(struct sk_buff_head *list, struct sk_buff *newsk); |
| 681 | static inline void __skb_queue_head(struct sk_buff_head *list, |
| 682 | struct sk_buff *newsk) |
| 683 | { |
Stephen Hemminger | 300ce17 | 2005-10-30 13:47:34 -0800 | [diff] [blame] | 684 | __skb_queue_after(list, (struct sk_buff *)list, newsk); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 685 | } |
| 686 | |
| 687 | /** |
| 688 | * __skb_queue_tail - queue a buffer at the list tail |
| 689 | * @list: list to use |
| 690 | * @newsk: buffer to queue |
| 691 | * |
| 692 | * Queue a buffer at the end of a list. This function takes no locks |
| 693 | * and you must therefore hold required locks before calling it. |
| 694 | * |
| 695 | * A buffer cannot be placed on two lists at the same time. |
| 696 | */ |
| 697 | extern void skb_queue_tail(struct sk_buff_head *list, struct sk_buff *newsk); |
| 698 | static inline void __skb_queue_tail(struct sk_buff_head *list, |
| 699 | struct sk_buff *newsk) |
| 700 | { |
| 701 | struct sk_buff *prev, *next; |
| 702 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 703 | list->qlen++; |
| 704 | next = (struct sk_buff *)list; |
| 705 | prev = next->prev; |
| 706 | newsk->next = next; |
| 707 | newsk->prev = prev; |
| 708 | next->prev = prev->next = newsk; |
| 709 | } |
| 710 | |
| 711 | |
| 712 | /** |
| 713 | * __skb_dequeue - remove from the head of the queue |
| 714 | * @list: list to dequeue from |
| 715 | * |
| 716 | * Remove the head of the list. This function does not take any locks |
| 717 | * so must be used with appropriate locks held only. The head item is |
| 718 | * returned or %NULL if the list is empty. |
| 719 | */ |
| 720 | extern struct sk_buff *skb_dequeue(struct sk_buff_head *list); |
| 721 | static inline struct sk_buff *__skb_dequeue(struct sk_buff_head *list) |
| 722 | { |
| 723 | struct sk_buff *next, *prev, *result; |
| 724 | |
| 725 | prev = (struct sk_buff *) list; |
| 726 | next = prev->next; |
| 727 | result = NULL; |
| 728 | if (next != prev) { |
| 729 | result = next; |
| 730 | next = next->next; |
| 731 | list->qlen--; |
| 732 | next->prev = prev; |
| 733 | prev->next = next; |
| 734 | result->next = result->prev = NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 735 | } |
| 736 | return result; |
| 737 | } |
| 738 | |
| 739 | |
| 740 | /* |
| 741 | * Insert a packet on a list. |
| 742 | */ |
David S. Miller | 8728b83 | 2005-08-09 19:25:21 -0700 | [diff] [blame] | 743 | extern void skb_insert(struct sk_buff *old, struct sk_buff *newsk, struct sk_buff_head *list); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 744 | static inline void __skb_insert(struct sk_buff *newsk, |
| 745 | struct sk_buff *prev, struct sk_buff *next, |
| 746 | struct sk_buff_head *list) |
| 747 | { |
| 748 | newsk->next = next; |
| 749 | newsk->prev = prev; |
| 750 | next->prev = prev->next = newsk; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 751 | list->qlen++; |
| 752 | } |
| 753 | |
| 754 | /* |
| 755 | * Place a packet after a given packet in a list. |
| 756 | */ |
David S. Miller | 8728b83 | 2005-08-09 19:25:21 -0700 | [diff] [blame] | 757 | extern void skb_append(struct sk_buff *old, struct sk_buff *newsk, struct sk_buff_head *list); |
| 758 | static inline void __skb_append(struct sk_buff *old, struct sk_buff *newsk, struct sk_buff_head *list) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 759 | { |
David S. Miller | 8728b83 | 2005-08-09 19:25:21 -0700 | [diff] [blame] | 760 | __skb_insert(newsk, old, old->next, list); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 761 | } |
| 762 | |
| 763 | /* |
| 764 | * remove sk_buff from list. _Must_ be called atomically, and with |
| 765 | * the list known.. |
| 766 | */ |
David S. Miller | 8728b83 | 2005-08-09 19:25:21 -0700 | [diff] [blame] | 767 | extern void skb_unlink(struct sk_buff *skb, struct sk_buff_head *list); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 768 | static inline void __skb_unlink(struct sk_buff *skb, struct sk_buff_head *list) |
| 769 | { |
| 770 | struct sk_buff *next, *prev; |
| 771 | |
| 772 | list->qlen--; |
| 773 | next = skb->next; |
| 774 | prev = skb->prev; |
| 775 | skb->next = skb->prev = NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 776 | next->prev = prev; |
| 777 | prev->next = next; |
| 778 | } |
| 779 | |
| 780 | |
| 781 | /* XXX: more streamlined implementation */ |
| 782 | |
| 783 | /** |
| 784 | * __skb_dequeue_tail - remove from the tail of the queue |
| 785 | * @list: list to dequeue from |
| 786 | * |
| 787 | * Remove the tail of the list. This function does not take any locks |
| 788 | * so must be used with appropriate locks held only. The tail item is |
| 789 | * returned or %NULL if the list is empty. |
| 790 | */ |
| 791 | extern struct sk_buff *skb_dequeue_tail(struct sk_buff_head *list); |
| 792 | static inline struct sk_buff *__skb_dequeue_tail(struct sk_buff_head *list) |
| 793 | { |
| 794 | struct sk_buff *skb = skb_peek_tail(list); |
| 795 | if (skb) |
| 796 | __skb_unlink(skb, list); |
| 797 | return skb; |
| 798 | } |
| 799 | |
| 800 | |
| 801 | static inline int skb_is_nonlinear(const struct sk_buff *skb) |
| 802 | { |
| 803 | return skb->data_len; |
| 804 | } |
| 805 | |
| 806 | static inline unsigned int skb_headlen(const struct sk_buff *skb) |
| 807 | { |
| 808 | return skb->len - skb->data_len; |
| 809 | } |
| 810 | |
| 811 | static inline int skb_pagelen(const struct sk_buff *skb) |
| 812 | { |
| 813 | int i, len = 0; |
| 814 | |
| 815 | for (i = (int)skb_shinfo(skb)->nr_frags - 1; i >= 0; i--) |
| 816 | len += skb_shinfo(skb)->frags[i].size; |
| 817 | return len + skb_headlen(skb); |
| 818 | } |
| 819 | |
| 820 | static inline void skb_fill_page_desc(struct sk_buff *skb, int i, |
| 821 | struct page *page, int off, int size) |
| 822 | { |
| 823 | skb_frag_t *frag = &skb_shinfo(skb)->frags[i]; |
| 824 | |
| 825 | frag->page = page; |
| 826 | frag->page_offset = off; |
| 827 | frag->size = size; |
| 828 | skb_shinfo(skb)->nr_frags = i + 1; |
| 829 | } |
| 830 | |
| 831 | #define SKB_PAGE_ASSERT(skb) BUG_ON(skb_shinfo(skb)->nr_frags) |
| 832 | #define SKB_FRAG_ASSERT(skb) BUG_ON(skb_shinfo(skb)->frag_list) |
| 833 | #define SKB_LINEAR_ASSERT(skb) BUG_ON(skb_is_nonlinear(skb)) |
| 834 | |
Arnaldo Carvalho de Melo | 27a884d | 2007-04-19 20:29:13 -0700 | [diff] [blame] | 835 | #ifdef NET_SKBUFF_DATA_USES_OFFSET |
| 836 | static inline unsigned char *skb_tail_pointer(const struct sk_buff *skb) |
| 837 | { |
| 838 | return skb->head + skb->tail; |
| 839 | } |
| 840 | |
| 841 | static inline void skb_reset_tail_pointer(struct sk_buff *skb) |
| 842 | { |
| 843 | skb->tail = skb->data - skb->head; |
| 844 | } |
| 845 | |
| 846 | static inline void skb_set_tail_pointer(struct sk_buff *skb, const int offset) |
| 847 | { |
| 848 | skb_reset_tail_pointer(skb); |
| 849 | skb->tail += offset; |
| 850 | } |
| 851 | #else /* NET_SKBUFF_DATA_USES_OFFSET */ |
| 852 | static inline unsigned char *skb_tail_pointer(const struct sk_buff *skb) |
| 853 | { |
| 854 | return skb->tail; |
| 855 | } |
| 856 | |
| 857 | static inline void skb_reset_tail_pointer(struct sk_buff *skb) |
| 858 | { |
| 859 | skb->tail = skb->data; |
| 860 | } |
| 861 | |
| 862 | static inline void skb_set_tail_pointer(struct sk_buff *skb, const int offset) |
| 863 | { |
| 864 | skb->tail = skb->data + offset; |
| 865 | } |
Arnaldo Carvalho de Melo | 4305b54 | 2007-04-19 20:43:29 -0700 | [diff] [blame] | 866 | |
Arnaldo Carvalho de Melo | 27a884d | 2007-04-19 20:29:13 -0700 | [diff] [blame] | 867 | #endif /* NET_SKBUFF_DATA_USES_OFFSET */ |
| 868 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 869 | /* |
| 870 | * Add data to an sk_buff |
| 871 | */ |
| 872 | static inline unsigned char *__skb_put(struct sk_buff *skb, unsigned int len) |
| 873 | { |
Arnaldo Carvalho de Melo | 27a884d | 2007-04-19 20:29:13 -0700 | [diff] [blame] | 874 | unsigned char *tmp = skb_tail_pointer(skb); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 875 | SKB_LINEAR_ASSERT(skb); |
| 876 | skb->tail += len; |
| 877 | skb->len += len; |
| 878 | return tmp; |
| 879 | } |
| 880 | |
| 881 | /** |
| 882 | * skb_put - add data to a buffer |
| 883 | * @skb: buffer to use |
| 884 | * @len: amount of data to add |
| 885 | * |
| 886 | * This function extends the used data area of the buffer. If this would |
| 887 | * exceed the total buffer size the kernel will panic. A pointer to the |
| 888 | * first byte of the extra data is returned. |
| 889 | */ |
| 890 | static inline unsigned char *skb_put(struct sk_buff *skb, unsigned int len) |
| 891 | { |
Arnaldo Carvalho de Melo | 27a884d | 2007-04-19 20:29:13 -0700 | [diff] [blame] | 892 | unsigned char *tmp = skb_tail_pointer(skb); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 893 | SKB_LINEAR_ASSERT(skb); |
| 894 | skb->tail += len; |
| 895 | skb->len += len; |
Arnaldo Carvalho de Melo | 4305b54 | 2007-04-19 20:43:29 -0700 | [diff] [blame] | 896 | if (unlikely(skb->tail > skb->end)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 897 | skb_over_panic(skb, len, current_text_addr()); |
| 898 | return tmp; |
| 899 | } |
| 900 | |
| 901 | static inline unsigned char *__skb_push(struct sk_buff *skb, unsigned int len) |
| 902 | { |
| 903 | skb->data -= len; |
| 904 | skb->len += len; |
| 905 | return skb->data; |
| 906 | } |
| 907 | |
| 908 | /** |
| 909 | * skb_push - add data to the start of a buffer |
| 910 | * @skb: buffer to use |
| 911 | * @len: amount of data to add |
| 912 | * |
| 913 | * This function extends the used data area of the buffer at the buffer |
| 914 | * start. If this would exceed the total buffer headroom the kernel will |
| 915 | * panic. A pointer to the first byte of the extra data is returned. |
| 916 | */ |
| 917 | static inline unsigned char *skb_push(struct sk_buff *skb, unsigned int len) |
| 918 | { |
| 919 | skb->data -= len; |
| 920 | skb->len += len; |
| 921 | if (unlikely(skb->data<skb->head)) |
| 922 | skb_under_panic(skb, len, current_text_addr()); |
| 923 | return skb->data; |
| 924 | } |
| 925 | |
| 926 | static inline unsigned char *__skb_pull(struct sk_buff *skb, unsigned int len) |
| 927 | { |
| 928 | skb->len -= len; |
| 929 | BUG_ON(skb->len < skb->data_len); |
| 930 | return skb->data += len; |
| 931 | } |
| 932 | |
| 933 | /** |
| 934 | * skb_pull - remove data from the start of a buffer |
| 935 | * @skb: buffer to use |
| 936 | * @len: amount of data to remove |
| 937 | * |
| 938 | * This function removes data from the start of a buffer, returning |
| 939 | * the memory to the headroom. A pointer to the next data in the buffer |
| 940 | * is returned. Once the data has been pulled future pushes will overwrite |
| 941 | * the old data. |
| 942 | */ |
| 943 | static inline unsigned char *skb_pull(struct sk_buff *skb, unsigned int len) |
| 944 | { |
| 945 | return unlikely(len > skb->len) ? NULL : __skb_pull(skb, len); |
| 946 | } |
| 947 | |
| 948 | extern unsigned char *__pskb_pull_tail(struct sk_buff *skb, int delta); |
| 949 | |
| 950 | static inline unsigned char *__pskb_pull(struct sk_buff *skb, unsigned int len) |
| 951 | { |
| 952 | if (len > skb_headlen(skb) && |
| 953 | !__pskb_pull_tail(skb, len-skb_headlen(skb))) |
| 954 | return NULL; |
| 955 | skb->len -= len; |
| 956 | return skb->data += len; |
| 957 | } |
| 958 | |
| 959 | static inline unsigned char *pskb_pull(struct sk_buff *skb, unsigned int len) |
| 960 | { |
| 961 | return unlikely(len > skb->len) ? NULL : __pskb_pull(skb, len); |
| 962 | } |
| 963 | |
| 964 | static inline int pskb_may_pull(struct sk_buff *skb, unsigned int len) |
| 965 | { |
| 966 | if (likely(len <= skb_headlen(skb))) |
| 967 | return 1; |
| 968 | if (unlikely(len > skb->len)) |
| 969 | return 0; |
| 970 | return __pskb_pull_tail(skb, len-skb_headlen(skb)) != NULL; |
| 971 | } |
| 972 | |
| 973 | /** |
| 974 | * skb_headroom - bytes at buffer head |
| 975 | * @skb: buffer to check |
| 976 | * |
| 977 | * Return the number of bytes of free space at the head of an &sk_buff. |
| 978 | */ |
| 979 | static inline int skb_headroom(const struct sk_buff *skb) |
| 980 | { |
| 981 | return skb->data - skb->head; |
| 982 | } |
| 983 | |
| 984 | /** |
| 985 | * skb_tailroom - bytes at buffer end |
| 986 | * @skb: buffer to check |
| 987 | * |
| 988 | * Return the number of bytes of free space at the tail of an sk_buff |
| 989 | */ |
| 990 | static inline int skb_tailroom(const struct sk_buff *skb) |
| 991 | { |
Arnaldo Carvalho de Melo | 4305b54 | 2007-04-19 20:43:29 -0700 | [diff] [blame] | 992 | return skb_is_nonlinear(skb) ? 0 : skb->end - skb->tail; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 993 | } |
| 994 | |
| 995 | /** |
| 996 | * skb_reserve - adjust headroom |
| 997 | * @skb: buffer to alter |
| 998 | * @len: bytes to move |
| 999 | * |
| 1000 | * Increase the headroom of an empty &sk_buff by reducing the tail |
| 1001 | * room. This is only allowed for an empty buffer. |
| 1002 | */ |
David S. Miller | 8243126 | 2006-01-17 02:54:21 -0800 | [diff] [blame] | 1003 | static inline void skb_reserve(struct sk_buff *skb, int len) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1004 | { |
| 1005 | skb->data += len; |
| 1006 | skb->tail += len; |
| 1007 | } |
| 1008 | |
Arnaldo Carvalho de Melo | 2e07fa9 | 2007-04-10 21:22:35 -0700 | [diff] [blame] | 1009 | #ifdef NET_SKBUFF_DATA_USES_OFFSET |
| 1010 | static inline unsigned char *skb_transport_header(const struct sk_buff *skb) |
| 1011 | { |
| 1012 | return skb->head + skb->transport_header; |
| 1013 | } |
| 1014 | |
| 1015 | static inline void skb_reset_transport_header(struct sk_buff *skb) |
| 1016 | { |
| 1017 | skb->transport_header = skb->data - skb->head; |
| 1018 | } |
| 1019 | |
| 1020 | static inline void skb_set_transport_header(struct sk_buff *skb, |
| 1021 | const int offset) |
| 1022 | { |
| 1023 | skb_reset_transport_header(skb); |
| 1024 | skb->transport_header += offset; |
| 1025 | } |
| 1026 | |
| 1027 | static inline unsigned char *skb_network_header(const struct sk_buff *skb) |
| 1028 | { |
| 1029 | return skb->head + skb->network_header; |
| 1030 | } |
| 1031 | |
| 1032 | static inline void skb_reset_network_header(struct sk_buff *skb) |
| 1033 | { |
| 1034 | skb->network_header = skb->data - skb->head; |
| 1035 | } |
| 1036 | |
| 1037 | static inline void skb_set_network_header(struct sk_buff *skb, const int offset) |
| 1038 | { |
| 1039 | skb_reset_network_header(skb); |
| 1040 | skb->network_header += offset; |
| 1041 | } |
| 1042 | |
| 1043 | static inline unsigned char *skb_mac_header(const struct sk_buff *skb) |
| 1044 | { |
| 1045 | return skb->head + skb->mac_header; |
| 1046 | } |
| 1047 | |
| 1048 | static inline int skb_mac_header_was_set(const struct sk_buff *skb) |
| 1049 | { |
| 1050 | return skb->mac_header != ~0U; |
| 1051 | } |
| 1052 | |
| 1053 | static inline void skb_reset_mac_header(struct sk_buff *skb) |
| 1054 | { |
| 1055 | skb->mac_header = skb->data - skb->head; |
| 1056 | } |
| 1057 | |
| 1058 | static inline void skb_set_mac_header(struct sk_buff *skb, const int offset) |
| 1059 | { |
| 1060 | skb_reset_mac_header(skb); |
| 1061 | skb->mac_header += offset; |
| 1062 | } |
| 1063 | |
| 1064 | #else /* NET_SKBUFF_DATA_USES_OFFSET */ |
| 1065 | |
Arnaldo Carvalho de Melo | 9c70220 | 2007-04-25 18:04:18 -0700 | [diff] [blame] | 1066 | static inline unsigned char *skb_transport_header(const struct sk_buff *skb) |
| 1067 | { |
Arnaldo Carvalho de Melo | b0e380b | 2007-04-10 21:21:55 -0700 | [diff] [blame] | 1068 | return skb->transport_header; |
Arnaldo Carvalho de Melo | 9c70220 | 2007-04-25 18:04:18 -0700 | [diff] [blame] | 1069 | } |
| 1070 | |
Arnaldo Carvalho de Melo | badff6d | 2007-03-13 13:06:52 -0300 | [diff] [blame] | 1071 | static inline void skb_reset_transport_header(struct sk_buff *skb) |
| 1072 | { |
Arnaldo Carvalho de Melo | b0e380b | 2007-04-10 21:21:55 -0700 | [diff] [blame] | 1073 | skb->transport_header = skb->data; |
Arnaldo Carvalho de Melo | badff6d | 2007-03-13 13:06:52 -0300 | [diff] [blame] | 1074 | } |
| 1075 | |
Arnaldo Carvalho de Melo | 967b05f | 2007-03-13 13:51:52 -0300 | [diff] [blame] | 1076 | static inline void skb_set_transport_header(struct sk_buff *skb, |
| 1077 | const int offset) |
| 1078 | { |
Arnaldo Carvalho de Melo | b0e380b | 2007-04-10 21:21:55 -0700 | [diff] [blame] | 1079 | skb->transport_header = skb->data + offset; |
Arnaldo Carvalho de Melo | 967b05f | 2007-03-13 13:51:52 -0300 | [diff] [blame] | 1080 | } |
| 1081 | |
Arnaldo Carvalho de Melo | d56f90a | 2007-04-10 20:50:43 -0700 | [diff] [blame] | 1082 | static inline unsigned char *skb_network_header(const struct sk_buff *skb) |
| 1083 | { |
Arnaldo Carvalho de Melo | b0e380b | 2007-04-10 21:21:55 -0700 | [diff] [blame] | 1084 | return skb->network_header; |
Arnaldo Carvalho de Melo | d56f90a | 2007-04-10 20:50:43 -0700 | [diff] [blame] | 1085 | } |
| 1086 | |
Arnaldo Carvalho de Melo | c1d2bbe | 2007-04-10 20:45:18 -0700 | [diff] [blame] | 1087 | static inline void skb_reset_network_header(struct sk_buff *skb) |
| 1088 | { |
Arnaldo Carvalho de Melo | b0e380b | 2007-04-10 21:21:55 -0700 | [diff] [blame] | 1089 | skb->network_header = skb->data; |
Arnaldo Carvalho de Melo | c1d2bbe | 2007-04-10 20:45:18 -0700 | [diff] [blame] | 1090 | } |
| 1091 | |
Arnaldo Carvalho de Melo | c14d245 | 2007-03-11 22:39:41 -0300 | [diff] [blame] | 1092 | static inline void skb_set_network_header(struct sk_buff *skb, const int offset) |
| 1093 | { |
Arnaldo Carvalho de Melo | b0e380b | 2007-04-10 21:21:55 -0700 | [diff] [blame] | 1094 | skb->network_header = skb->data + offset; |
Arnaldo Carvalho de Melo | c14d245 | 2007-03-11 22:39:41 -0300 | [diff] [blame] | 1095 | } |
| 1096 | |
Arnaldo Carvalho de Melo | 98e399f | 2007-03-19 15:33:04 -0700 | [diff] [blame] | 1097 | static inline unsigned char *skb_mac_header(const struct sk_buff *skb) |
| 1098 | { |
Arnaldo Carvalho de Melo | b0e380b | 2007-04-10 21:21:55 -0700 | [diff] [blame] | 1099 | return skb->mac_header; |
Arnaldo Carvalho de Melo | 98e399f | 2007-03-19 15:33:04 -0700 | [diff] [blame] | 1100 | } |
| 1101 | |
| 1102 | static inline int skb_mac_header_was_set(const struct sk_buff *skb) |
| 1103 | { |
Arnaldo Carvalho de Melo | b0e380b | 2007-04-10 21:21:55 -0700 | [diff] [blame] | 1104 | return skb->mac_header != NULL; |
Arnaldo Carvalho de Melo | 98e399f | 2007-03-19 15:33:04 -0700 | [diff] [blame] | 1105 | } |
| 1106 | |
Arnaldo Carvalho de Melo | 459a98e | 2007-03-19 15:30:44 -0700 | [diff] [blame] | 1107 | static inline void skb_reset_mac_header(struct sk_buff *skb) |
| 1108 | { |
Arnaldo Carvalho de Melo | b0e380b | 2007-04-10 21:21:55 -0700 | [diff] [blame] | 1109 | skb->mac_header = skb->data; |
Arnaldo Carvalho de Melo | 459a98e | 2007-03-19 15:30:44 -0700 | [diff] [blame] | 1110 | } |
| 1111 | |
Arnaldo Carvalho de Melo | 48d49d0c | 2007-03-10 12:30:58 -0300 | [diff] [blame] | 1112 | static inline void skb_set_mac_header(struct sk_buff *skb, const int offset) |
| 1113 | { |
Arnaldo Carvalho de Melo | b0e380b | 2007-04-10 21:21:55 -0700 | [diff] [blame] | 1114 | skb->mac_header = skb->data + offset; |
Arnaldo Carvalho de Melo | 48d49d0c | 2007-03-10 12:30:58 -0300 | [diff] [blame] | 1115 | } |
Arnaldo Carvalho de Melo | 2e07fa9 | 2007-04-10 21:22:35 -0700 | [diff] [blame] | 1116 | #endif /* NET_SKBUFF_DATA_USES_OFFSET */ |
| 1117 | |
| 1118 | static inline int skb_transport_offset(const struct sk_buff *skb) |
| 1119 | { |
| 1120 | return skb_transport_header(skb) - skb->data; |
| 1121 | } |
| 1122 | |
| 1123 | static inline u32 skb_network_header_len(const struct sk_buff *skb) |
| 1124 | { |
| 1125 | return skb->transport_header - skb->network_header; |
| 1126 | } |
| 1127 | |
| 1128 | static inline int skb_network_offset(const struct sk_buff *skb) |
| 1129 | { |
| 1130 | return skb_network_header(skb) - skb->data; |
| 1131 | } |
Arnaldo Carvalho de Melo | 48d49d0c | 2007-03-10 12:30:58 -0300 | [diff] [blame] | 1132 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1133 | /* |
| 1134 | * CPUs often take a performance hit when accessing unaligned memory |
| 1135 | * locations. The actual performance hit varies, it can be small if the |
| 1136 | * hardware handles it or large if we have to take an exception and fix it |
| 1137 | * in software. |
| 1138 | * |
| 1139 | * Since an ethernet header is 14 bytes network drivers often end up with |
| 1140 | * the IP header at an unaligned offset. The IP header can be aligned by |
| 1141 | * shifting the start of the packet by 2 bytes. Drivers should do this |
| 1142 | * with: |
| 1143 | * |
| 1144 | * skb_reserve(NET_IP_ALIGN); |
| 1145 | * |
| 1146 | * The downside to this alignment of the IP header is that the DMA is now |
| 1147 | * unaligned. On some architectures the cost of an unaligned DMA is high |
| 1148 | * and this cost outweighs the gains made by aligning the IP header. |
| 1149 | * |
| 1150 | * Since this trade off varies between architectures, we allow NET_IP_ALIGN |
| 1151 | * to be overridden. |
| 1152 | */ |
| 1153 | #ifndef NET_IP_ALIGN |
| 1154 | #define NET_IP_ALIGN 2 |
| 1155 | #endif |
| 1156 | |
Anton Blanchard | 025be81 | 2006-03-31 02:27:06 -0800 | [diff] [blame] | 1157 | /* |
| 1158 | * The networking layer reserves some headroom in skb data (via |
| 1159 | * dev_alloc_skb). This is used to avoid having to reallocate skb data when |
| 1160 | * the header has to grow. In the default case, if the header has to grow |
| 1161 | * 16 bytes or less we avoid the reallocation. |
| 1162 | * |
| 1163 | * Unfortunately this headroom changes the DMA alignment of the resulting |
| 1164 | * network packet. As for NET_IP_ALIGN, this unaligned DMA is expensive |
| 1165 | * on some architectures. An architecture can override this value, |
| 1166 | * perhaps setting it to a cacheline in size (since that will maintain |
| 1167 | * cacheline alignment of the DMA). It must be a power of 2. |
| 1168 | * |
| 1169 | * Various parts of the networking layer expect at least 16 bytes of |
| 1170 | * headroom, you should not reduce this. |
| 1171 | */ |
| 1172 | #ifndef NET_SKB_PAD |
| 1173 | #define NET_SKB_PAD 16 |
| 1174 | #endif |
| 1175 | |
Herbert Xu | 3cc0e87 | 2006-06-09 16:13:38 -0700 | [diff] [blame] | 1176 | extern int ___pskb_trim(struct sk_buff *skb, unsigned int len); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1177 | |
| 1178 | static inline void __skb_trim(struct sk_buff *skb, unsigned int len) |
| 1179 | { |
Herbert Xu | 3cc0e87 | 2006-06-09 16:13:38 -0700 | [diff] [blame] | 1180 | if (unlikely(skb->data_len)) { |
| 1181 | WARN_ON(1); |
| 1182 | return; |
| 1183 | } |
Arnaldo Carvalho de Melo | 27a884d | 2007-04-19 20:29:13 -0700 | [diff] [blame] | 1184 | skb->len = len; |
| 1185 | skb_set_tail_pointer(skb, len); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1186 | } |
| 1187 | |
| 1188 | /** |
| 1189 | * skb_trim - remove end from a buffer |
| 1190 | * @skb: buffer to alter |
| 1191 | * @len: new length |
| 1192 | * |
| 1193 | * Cut the length of a buffer down by removing data from the tail. If |
| 1194 | * the buffer is already under the length specified it is not modified. |
Herbert Xu | 3cc0e87 | 2006-06-09 16:13:38 -0700 | [diff] [blame] | 1195 | * The skb must be linear. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1196 | */ |
| 1197 | static inline void skb_trim(struct sk_buff *skb, unsigned int len) |
| 1198 | { |
| 1199 | if (skb->len > len) |
| 1200 | __skb_trim(skb, len); |
| 1201 | } |
| 1202 | |
| 1203 | |
| 1204 | static inline int __pskb_trim(struct sk_buff *skb, unsigned int len) |
| 1205 | { |
Herbert Xu | 3cc0e87 | 2006-06-09 16:13:38 -0700 | [diff] [blame] | 1206 | if (skb->data_len) |
| 1207 | return ___pskb_trim(skb, len); |
| 1208 | __skb_trim(skb, len); |
| 1209 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1210 | } |
| 1211 | |
| 1212 | static inline int pskb_trim(struct sk_buff *skb, unsigned int len) |
| 1213 | { |
| 1214 | return (len < skb->len) ? __pskb_trim(skb, len) : 0; |
| 1215 | } |
| 1216 | |
| 1217 | /** |
Herbert Xu | e9fa4f7 | 2006-08-13 20:12:58 -0700 | [diff] [blame] | 1218 | * pskb_trim_unique - remove end from a paged unique (not cloned) buffer |
| 1219 | * @skb: buffer to alter |
| 1220 | * @len: new length |
| 1221 | * |
| 1222 | * This is identical to pskb_trim except that the caller knows that |
| 1223 | * the skb is not cloned so we should never get an error due to out- |
| 1224 | * of-memory. |
| 1225 | */ |
| 1226 | static inline void pskb_trim_unique(struct sk_buff *skb, unsigned int len) |
| 1227 | { |
| 1228 | int err = pskb_trim(skb, len); |
| 1229 | BUG_ON(err); |
| 1230 | } |
| 1231 | |
| 1232 | /** |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1233 | * skb_orphan - orphan a buffer |
| 1234 | * @skb: buffer to orphan |
| 1235 | * |
| 1236 | * If a buffer currently has an owner then we call the owner's |
| 1237 | * destructor function and make the @skb unowned. The buffer continues |
| 1238 | * to exist but is no longer charged to its former owner. |
| 1239 | */ |
| 1240 | static inline void skb_orphan(struct sk_buff *skb) |
| 1241 | { |
| 1242 | if (skb->destructor) |
| 1243 | skb->destructor(skb); |
| 1244 | skb->destructor = NULL; |
| 1245 | skb->sk = NULL; |
| 1246 | } |
| 1247 | |
| 1248 | /** |
| 1249 | * __skb_queue_purge - empty a list |
| 1250 | * @list: list to empty |
| 1251 | * |
| 1252 | * Delete all buffers on an &sk_buff list. Each buffer is removed from |
| 1253 | * the list and one reference dropped. This function does not take the |
| 1254 | * list lock and the caller must hold the relevant locks to use it. |
| 1255 | */ |
| 1256 | extern void skb_queue_purge(struct sk_buff_head *list); |
| 1257 | static inline void __skb_queue_purge(struct sk_buff_head *list) |
| 1258 | { |
| 1259 | struct sk_buff *skb; |
| 1260 | while ((skb = __skb_dequeue(list)) != NULL) |
| 1261 | kfree_skb(skb); |
| 1262 | } |
| 1263 | |
| 1264 | /** |
Christoph Hellwig | b4e54de | 2006-07-24 15:31:14 -0700 | [diff] [blame] | 1265 | * __dev_alloc_skb - allocate an skbuff for receiving |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1266 | * @length: length to allocate |
| 1267 | * @gfp_mask: get_free_pages mask, passed to alloc_skb |
| 1268 | * |
| 1269 | * Allocate a new &sk_buff and assign it a usage count of one. The |
| 1270 | * buffer has unspecified headroom built in. Users should allocate |
| 1271 | * the headroom they think they need without accounting for the |
| 1272 | * built in space. The built in space is used for optimisations. |
| 1273 | * |
Christoph Hellwig | 766ea8c | 2006-08-07 15:49:53 -0700 | [diff] [blame] | 1274 | * %NULL is returned if there is no free memory. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1275 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1276 | static inline struct sk_buff *__dev_alloc_skb(unsigned int length, |
Al Viro | dd0fc66 | 2005-10-07 07:46:04 +0100 | [diff] [blame] | 1277 | gfp_t gfp_mask) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1278 | { |
Anton Blanchard | 025be81 | 2006-03-31 02:27:06 -0800 | [diff] [blame] | 1279 | struct sk_buff *skb = alloc_skb(length + NET_SKB_PAD, gfp_mask); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1280 | if (likely(skb)) |
Anton Blanchard | 025be81 | 2006-03-31 02:27:06 -0800 | [diff] [blame] | 1281 | skb_reserve(skb, NET_SKB_PAD); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1282 | return skb; |
| 1283 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1284 | |
| 1285 | /** |
Christoph Hellwig | b4e54de | 2006-07-24 15:31:14 -0700 | [diff] [blame] | 1286 | * dev_alloc_skb - allocate an skbuff for receiving |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1287 | * @length: length to allocate |
| 1288 | * |
| 1289 | * Allocate a new &sk_buff and assign it a usage count of one. The |
| 1290 | * buffer has unspecified headroom built in. Users should allocate |
| 1291 | * the headroom they think they need without accounting for the |
| 1292 | * built in space. The built in space is used for optimisations. |
| 1293 | * |
Christoph Hellwig | 766ea8c | 2006-08-07 15:49:53 -0700 | [diff] [blame] | 1294 | * %NULL is returned if there is no free memory. Although this function |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1295 | * allocates memory it can be called from an interrupt. |
| 1296 | */ |
| 1297 | static inline struct sk_buff *dev_alloc_skb(unsigned int length) |
| 1298 | { |
| 1299 | return __dev_alloc_skb(length, GFP_ATOMIC); |
| 1300 | } |
| 1301 | |
Christoph Hellwig | 8af2745 | 2006-07-31 22:35:23 -0700 | [diff] [blame] | 1302 | extern struct sk_buff *__netdev_alloc_skb(struct net_device *dev, |
| 1303 | unsigned int length, gfp_t gfp_mask); |
| 1304 | |
| 1305 | /** |
| 1306 | * netdev_alloc_skb - allocate an skbuff for rx on a specific device |
| 1307 | * @dev: network device to receive on |
| 1308 | * @length: length to allocate |
| 1309 | * |
| 1310 | * Allocate a new &sk_buff and assign it a usage count of one. The |
| 1311 | * buffer has unspecified headroom built in. Users should allocate |
| 1312 | * the headroom they think they need without accounting for the |
| 1313 | * built in space. The built in space is used for optimisations. |
| 1314 | * |
| 1315 | * %NULL is returned if there is no free memory. Although this function |
| 1316 | * allocates memory it can be called from an interrupt. |
| 1317 | */ |
| 1318 | static inline struct sk_buff *netdev_alloc_skb(struct net_device *dev, |
| 1319 | unsigned int length) |
| 1320 | { |
| 1321 | return __netdev_alloc_skb(dev, length, GFP_ATOMIC); |
| 1322 | } |
| 1323 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1324 | /** |
| 1325 | * skb_cow - copy header of skb when it is required |
| 1326 | * @skb: buffer to cow |
| 1327 | * @headroom: needed headroom |
| 1328 | * |
| 1329 | * If the skb passed lacks sufficient headroom or its data part |
| 1330 | * is shared, data is reallocated. If reallocation fails, an error |
| 1331 | * is returned and original skb is not changed. |
| 1332 | * |
| 1333 | * The result is skb with writable area skb->head...skb->tail |
| 1334 | * and at least @headroom of space at head. |
| 1335 | */ |
| 1336 | static inline int skb_cow(struct sk_buff *skb, unsigned int headroom) |
| 1337 | { |
Anton Blanchard | 025be81 | 2006-03-31 02:27:06 -0800 | [diff] [blame] | 1338 | int delta = (headroom > NET_SKB_PAD ? headroom : NET_SKB_PAD) - |
| 1339 | skb_headroom(skb); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1340 | |
| 1341 | if (delta < 0) |
| 1342 | delta = 0; |
| 1343 | |
| 1344 | if (delta || skb_cloned(skb)) |
Anton Blanchard | 025be81 | 2006-03-31 02:27:06 -0800 | [diff] [blame] | 1345 | return pskb_expand_head(skb, (delta + (NET_SKB_PAD-1)) & |
| 1346 | ~(NET_SKB_PAD-1), 0, GFP_ATOMIC); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1347 | return 0; |
| 1348 | } |
| 1349 | |
| 1350 | /** |
| 1351 | * skb_padto - pad an skbuff up to a minimal size |
| 1352 | * @skb: buffer to pad |
| 1353 | * @len: minimal length |
| 1354 | * |
| 1355 | * Pads up a buffer to ensure the trailing bytes exist and are |
| 1356 | * blanked. If the buffer already contains sufficient data it |
Herbert Xu | 5b057c6 | 2006-06-23 02:06:41 -0700 | [diff] [blame] | 1357 | * is untouched. Otherwise it is extended. Returns zero on |
| 1358 | * success. The skb is freed on error. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1359 | */ |
| 1360 | |
Herbert Xu | 5b057c6 | 2006-06-23 02:06:41 -0700 | [diff] [blame] | 1361 | static inline int skb_padto(struct sk_buff *skb, unsigned int len) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1362 | { |
| 1363 | unsigned int size = skb->len; |
| 1364 | if (likely(size >= len)) |
Herbert Xu | 5b057c6 | 2006-06-23 02:06:41 -0700 | [diff] [blame] | 1365 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1366 | return skb_pad(skb, len-size); |
| 1367 | } |
| 1368 | |
| 1369 | static inline int skb_add_data(struct sk_buff *skb, |
| 1370 | char __user *from, int copy) |
| 1371 | { |
| 1372 | const int off = skb->len; |
| 1373 | |
| 1374 | if (skb->ip_summed == CHECKSUM_NONE) { |
| 1375 | int err = 0; |
Al Viro | 5084205 | 2006-11-14 21:36:34 -0800 | [diff] [blame] | 1376 | __wsum csum = csum_and_copy_from_user(from, skb_put(skb, copy), |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1377 | copy, 0, &err); |
| 1378 | if (!err) { |
| 1379 | skb->csum = csum_block_add(skb->csum, csum, off); |
| 1380 | return 0; |
| 1381 | } |
| 1382 | } else if (!copy_from_user(skb_put(skb, copy), from, copy)) |
| 1383 | return 0; |
| 1384 | |
| 1385 | __skb_trim(skb, off); |
| 1386 | return -EFAULT; |
| 1387 | } |
| 1388 | |
| 1389 | static inline int skb_can_coalesce(struct sk_buff *skb, int i, |
| 1390 | struct page *page, int off) |
| 1391 | { |
| 1392 | if (i) { |
| 1393 | struct skb_frag_struct *frag = &skb_shinfo(skb)->frags[i - 1]; |
| 1394 | |
| 1395 | return page == frag->page && |
| 1396 | off == frag->page_offset + frag->size; |
| 1397 | } |
| 1398 | return 0; |
| 1399 | } |
| 1400 | |
Herbert Xu | 364c6ba | 2006-06-09 16:10:40 -0700 | [diff] [blame] | 1401 | static inline int __skb_linearize(struct sk_buff *skb) |
| 1402 | { |
| 1403 | return __pskb_pull_tail(skb, skb->data_len) ? 0 : -ENOMEM; |
| 1404 | } |
| 1405 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1406 | /** |
| 1407 | * skb_linearize - convert paged skb to linear one |
| 1408 | * @skb: buffer to linarize |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1409 | * |
| 1410 | * If there is no free memory -ENOMEM is returned, otherwise zero |
| 1411 | * is returned and the old skb data released. |
| 1412 | */ |
Herbert Xu | 364c6ba | 2006-06-09 16:10:40 -0700 | [diff] [blame] | 1413 | static inline int skb_linearize(struct sk_buff *skb) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1414 | { |
Herbert Xu | 364c6ba | 2006-06-09 16:10:40 -0700 | [diff] [blame] | 1415 | return skb_is_nonlinear(skb) ? __skb_linearize(skb) : 0; |
| 1416 | } |
| 1417 | |
| 1418 | /** |
| 1419 | * skb_linearize_cow - make sure skb is linear and writable |
| 1420 | * @skb: buffer to process |
| 1421 | * |
| 1422 | * If there is no free memory -ENOMEM is returned, otherwise zero |
| 1423 | * is returned and the old skb data released. |
| 1424 | */ |
| 1425 | static inline int skb_linearize_cow(struct sk_buff *skb) |
| 1426 | { |
| 1427 | return skb_is_nonlinear(skb) || skb_cloned(skb) ? |
| 1428 | __skb_linearize(skb) : 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1429 | } |
| 1430 | |
| 1431 | /** |
| 1432 | * skb_postpull_rcsum - update checksum for received skb after pull |
| 1433 | * @skb: buffer to update |
| 1434 | * @start: start of data before pull |
| 1435 | * @len: length of data pulled |
| 1436 | * |
| 1437 | * After doing a pull on a received packet, you need to call this to |
Patrick McHardy | 84fa793 | 2006-08-29 16:44:56 -0700 | [diff] [blame] | 1438 | * update the CHECKSUM_COMPLETE checksum, or set ip_summed to |
| 1439 | * CHECKSUM_NONE so that it can be recomputed from scratch. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1440 | */ |
| 1441 | |
| 1442 | static inline void skb_postpull_rcsum(struct sk_buff *skb, |
Herbert Xu | cbb042f | 2006-03-20 22:43:56 -0800 | [diff] [blame] | 1443 | const void *start, unsigned int len) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1444 | { |
Patrick McHardy | 84fa793 | 2006-08-29 16:44:56 -0700 | [diff] [blame] | 1445 | if (skb->ip_summed == CHECKSUM_COMPLETE) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1446 | skb->csum = csum_sub(skb->csum, csum_partial(start, len, 0)); |
| 1447 | } |
| 1448 | |
Herbert Xu | cbb042f | 2006-03-20 22:43:56 -0800 | [diff] [blame] | 1449 | unsigned char *skb_pull_rcsum(struct sk_buff *skb, unsigned int len); |
| 1450 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1451 | /** |
| 1452 | * pskb_trim_rcsum - trim received skb and update checksum |
| 1453 | * @skb: buffer to trim |
| 1454 | * @len: new length |
| 1455 | * |
| 1456 | * This is exactly the same as pskb_trim except that it ensures the |
| 1457 | * checksum of received packets are still valid after the operation. |
| 1458 | */ |
| 1459 | |
| 1460 | static inline int pskb_trim_rcsum(struct sk_buff *skb, unsigned int len) |
| 1461 | { |
Stephen Hemminger | 0e4e422 | 2005-09-08 12:32:03 -0700 | [diff] [blame] | 1462 | if (likely(len >= skb->len)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1463 | return 0; |
Patrick McHardy | 84fa793 | 2006-08-29 16:44:56 -0700 | [diff] [blame] | 1464 | if (skb->ip_summed == CHECKSUM_COMPLETE) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1465 | skb->ip_summed = CHECKSUM_NONE; |
| 1466 | return __pskb_trim(skb, len); |
| 1467 | } |
| 1468 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1469 | #define skb_queue_walk(queue, skb) \ |
| 1470 | for (skb = (queue)->next; \ |
| 1471 | prefetch(skb->next), (skb != (struct sk_buff *)(queue)); \ |
| 1472 | skb = skb->next) |
| 1473 | |
James Chapman | 46f8914 | 2007-04-30 00:07:31 -0700 | [diff] [blame] | 1474 | #define skb_queue_walk_safe(queue, skb, tmp) \ |
| 1475 | for (skb = (queue)->next, tmp = skb->next; \ |
| 1476 | skb != (struct sk_buff *)(queue); \ |
| 1477 | skb = tmp, tmp = skb->next) |
| 1478 | |
Stephen Hemminger | 300ce17 | 2005-10-30 13:47:34 -0800 | [diff] [blame] | 1479 | #define skb_queue_reverse_walk(queue, skb) \ |
| 1480 | for (skb = (queue)->prev; \ |
| 1481 | prefetch(skb->prev), (skb != (struct sk_buff *)(queue)); \ |
| 1482 | skb = skb->prev) |
| 1483 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1484 | |
| 1485 | extern struct sk_buff *skb_recv_datagram(struct sock *sk, unsigned flags, |
| 1486 | int noblock, int *err); |
| 1487 | extern unsigned int datagram_poll(struct file *file, struct socket *sock, |
| 1488 | struct poll_table_struct *wait); |
| 1489 | extern int skb_copy_datagram_iovec(const struct sk_buff *from, |
| 1490 | int offset, struct iovec *to, |
| 1491 | int size); |
Herbert Xu | fb286bb | 2005-11-10 13:01:24 -0800 | [diff] [blame] | 1492 | extern int skb_copy_and_csum_datagram_iovec(struct sk_buff *skb, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1493 | int hlen, |
| 1494 | struct iovec *iov); |
| 1495 | extern void skb_free_datagram(struct sock *sk, struct sk_buff *skb); |
Herbert Xu | 3305b80 | 2005-12-13 23:16:37 -0800 | [diff] [blame] | 1496 | extern void skb_kill_datagram(struct sock *sk, struct sk_buff *skb, |
| 1497 | unsigned int flags); |
Al Viro | 2bbbc86 | 2006-11-14 21:37:14 -0800 | [diff] [blame] | 1498 | extern __wsum skb_checksum(const struct sk_buff *skb, int offset, |
| 1499 | int len, __wsum csum); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1500 | extern int skb_copy_bits(const struct sk_buff *skb, int offset, |
| 1501 | void *to, int len); |
Stephen Hemminger | 0c6fcc8 | 2007-04-20 16:40:01 -0700 | [diff] [blame] | 1502 | extern int skb_store_bits(struct sk_buff *skb, int offset, |
| 1503 | const void *from, int len); |
Al Viro | 81d7766 | 2006-11-14 21:37:33 -0800 | [diff] [blame] | 1504 | extern __wsum skb_copy_and_csum_bits(const struct sk_buff *skb, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1505 | int offset, u8 *to, int len, |
Al Viro | 81d7766 | 2006-11-14 21:37:33 -0800 | [diff] [blame] | 1506 | __wsum csum); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1507 | extern void skb_copy_and_csum_dev(const struct sk_buff *skb, u8 *to); |
| 1508 | extern void skb_split(struct sk_buff *skb, |
| 1509 | struct sk_buff *skb1, const u32 len); |
| 1510 | |
Herbert Xu | 576a30e | 2006-06-27 13:22:38 -0700 | [diff] [blame] | 1511 | extern struct sk_buff *skb_segment(struct sk_buff *skb, int features); |
Arnaldo Carvalho de Melo | 2038073 | 2005-08-16 02:18:02 -0300 | [diff] [blame] | 1512 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1513 | static inline void *skb_header_pointer(const struct sk_buff *skb, int offset, |
| 1514 | int len, void *buffer) |
| 1515 | { |
| 1516 | int hlen = skb_headlen(skb); |
| 1517 | |
Patrick McHardy | 55820ee | 2005-07-05 14:08:10 -0700 | [diff] [blame] | 1518 | if (hlen - offset >= len) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1519 | return skb->data + offset; |
| 1520 | |
| 1521 | if (skb_copy_bits(skb, offset, buffer, len) < 0) |
| 1522 | return NULL; |
| 1523 | |
| 1524 | return buffer; |
| 1525 | } |
| 1526 | |
Arnaldo Carvalho de Melo | d626f62 | 2007-03-27 18:55:52 -0300 | [diff] [blame] | 1527 | static inline void skb_copy_from_linear_data(const struct sk_buff *skb, |
| 1528 | void *to, |
| 1529 | const unsigned int len) |
| 1530 | { |
| 1531 | memcpy(to, skb->data, len); |
| 1532 | } |
| 1533 | |
| 1534 | static inline void skb_copy_from_linear_data_offset(const struct sk_buff *skb, |
| 1535 | const int offset, void *to, |
| 1536 | const unsigned int len) |
| 1537 | { |
| 1538 | memcpy(to, skb->data + offset, len); |
| 1539 | } |
| 1540 | |
Arnaldo Carvalho de Melo | 27d7ff4 | 2007-03-31 11:55:19 -0300 | [diff] [blame] | 1541 | static inline void skb_copy_to_linear_data(struct sk_buff *skb, |
| 1542 | const void *from, |
| 1543 | const unsigned int len) |
| 1544 | { |
| 1545 | memcpy(skb->data, from, len); |
| 1546 | } |
| 1547 | |
| 1548 | static inline void skb_copy_to_linear_data_offset(struct sk_buff *skb, |
| 1549 | const int offset, |
| 1550 | const void *from, |
| 1551 | const unsigned int len) |
| 1552 | { |
| 1553 | memcpy(skb->data + offset, from, len); |
| 1554 | } |
| 1555 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1556 | extern void skb_init(void); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1557 | |
Patrick McHardy | a61bbcf | 2005-08-14 17:24:31 -0700 | [diff] [blame] | 1558 | /** |
| 1559 | * skb_get_timestamp - get timestamp from a skb |
| 1560 | * @skb: skb to get stamp from |
| 1561 | * @stamp: pointer to struct timeval to store stamp in |
| 1562 | * |
| 1563 | * Timestamps are stored in the skb as offsets to a base timestamp. |
| 1564 | * This function converts the offset back to a struct timeval and stores |
| 1565 | * it in stamp. |
| 1566 | */ |
Stephen Hemminger | f2c3839 | 2005-09-06 15:48:03 -0700 | [diff] [blame] | 1567 | static inline void skb_get_timestamp(const struct sk_buff *skb, struct timeval *stamp) |
Patrick McHardy | a61bbcf | 2005-08-14 17:24:31 -0700 | [diff] [blame] | 1568 | { |
Eric Dumazet | b7aa0bf | 2007-04-19 16:16:32 -0700 | [diff] [blame] | 1569 | *stamp = ktime_to_timeval(skb->tstamp); |
Patrick McHardy | a61bbcf | 2005-08-14 17:24:31 -0700 | [diff] [blame] | 1570 | } |
| 1571 | |
Eric Dumazet | b7aa0bf | 2007-04-19 16:16:32 -0700 | [diff] [blame] | 1572 | static inline void __net_timestamp(struct sk_buff *skb) |
Patrick McHardy | a61bbcf | 2005-08-14 17:24:31 -0700 | [diff] [blame] | 1573 | { |
Eric Dumazet | b7aa0bf | 2007-04-19 16:16:32 -0700 | [diff] [blame] | 1574 | skb->tstamp = ktime_get_real(); |
Patrick McHardy | a61bbcf | 2005-08-14 17:24:31 -0700 | [diff] [blame] | 1575 | } |
| 1576 | |
Stephen Hemminger | 164891a | 2007-04-23 22:26:16 -0700 | [diff] [blame] | 1577 | static inline ktime_t net_timedelta(ktime_t t) |
| 1578 | { |
| 1579 | return ktime_sub(ktime_get_real(), t); |
| 1580 | } |
| 1581 | |
Ilpo Järvinen | b9ce204 | 2007-06-15 15:08:43 -0700 | [diff] [blame] | 1582 | static inline ktime_t net_invalid_timestamp(void) |
| 1583 | { |
| 1584 | return ktime_set(0, 0); |
| 1585 | } |
Patrick McHardy | a61bbcf | 2005-08-14 17:24:31 -0700 | [diff] [blame] | 1586 | |
Herbert Xu | 759e5d0 | 2007-03-25 20:10:56 -0700 | [diff] [blame] | 1587 | extern __sum16 __skb_checksum_complete_head(struct sk_buff *skb, int len); |
Al Viro | b51655b | 2006-11-14 21:40:42 -0800 | [diff] [blame] | 1588 | extern __sum16 __skb_checksum_complete(struct sk_buff *skb); |
Herbert Xu | fb286bb | 2005-11-10 13:01:24 -0800 | [diff] [blame] | 1589 | |
Herbert Xu | 6047637 | 2007-04-09 11:59:39 -0700 | [diff] [blame] | 1590 | static inline int skb_csum_unnecessary(const struct sk_buff *skb) |
| 1591 | { |
| 1592 | return skb->ip_summed & CHECKSUM_UNNECESSARY; |
| 1593 | } |
| 1594 | |
Herbert Xu | fb286bb | 2005-11-10 13:01:24 -0800 | [diff] [blame] | 1595 | /** |
| 1596 | * skb_checksum_complete - Calculate checksum of an entire packet |
| 1597 | * @skb: packet to process |
| 1598 | * |
| 1599 | * This function calculates the checksum over the entire packet plus |
| 1600 | * the value of skb->csum. The latter can be used to supply the |
| 1601 | * checksum of a pseudo header as used by TCP/UDP. It returns the |
| 1602 | * checksum. |
| 1603 | * |
| 1604 | * For protocols that contain complete checksums such as ICMP/TCP/UDP, |
| 1605 | * this function can be used to verify that checksum on received |
| 1606 | * packets. In that case the function should return zero if the |
| 1607 | * checksum is correct. In particular, this function will return zero |
| 1608 | * if skb->ip_summed is CHECKSUM_UNNECESSARY which indicates that the |
| 1609 | * hardware has already verified the correctness of the checksum. |
| 1610 | */ |
| 1611 | static inline unsigned int skb_checksum_complete(struct sk_buff *skb) |
| 1612 | { |
Herbert Xu | 6047637 | 2007-04-09 11:59:39 -0700 | [diff] [blame] | 1613 | return skb_csum_unnecessary(skb) ? |
| 1614 | 0 : __skb_checksum_complete(skb); |
Herbert Xu | fb286bb | 2005-11-10 13:01:24 -0800 | [diff] [blame] | 1615 | } |
| 1616 | |
Yasuyuki Kozakai | 5f79e0f | 2007-03-23 11:17:07 -0700 | [diff] [blame] | 1617 | #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE) |
Yasuyuki Kozakai | de6e05c | 2007-03-23 11:17:27 -0700 | [diff] [blame] | 1618 | extern void nf_conntrack_destroy(struct nf_conntrack *nfct); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1619 | static inline void nf_conntrack_put(struct nf_conntrack *nfct) |
| 1620 | { |
| 1621 | if (nfct && atomic_dec_and_test(&nfct->use)) |
Yasuyuki Kozakai | de6e05c | 2007-03-23 11:17:27 -0700 | [diff] [blame] | 1622 | nf_conntrack_destroy(nfct); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1623 | } |
| 1624 | static inline void nf_conntrack_get(struct nf_conntrack *nfct) |
| 1625 | { |
| 1626 | if (nfct) |
| 1627 | atomic_inc(&nfct->use); |
| 1628 | } |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 1629 | static inline void nf_conntrack_get_reasm(struct sk_buff *skb) |
| 1630 | { |
| 1631 | if (skb) |
| 1632 | atomic_inc(&skb->users); |
| 1633 | } |
| 1634 | static inline void nf_conntrack_put_reasm(struct sk_buff *skb) |
| 1635 | { |
| 1636 | if (skb) |
| 1637 | kfree_skb(skb); |
| 1638 | } |
| 1639 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1640 | #ifdef CONFIG_BRIDGE_NETFILTER |
| 1641 | static inline void nf_bridge_put(struct nf_bridge_info *nf_bridge) |
| 1642 | { |
| 1643 | if (nf_bridge && atomic_dec_and_test(&nf_bridge->use)) |
| 1644 | kfree(nf_bridge); |
| 1645 | } |
| 1646 | static inline void nf_bridge_get(struct nf_bridge_info *nf_bridge) |
| 1647 | { |
| 1648 | if (nf_bridge) |
| 1649 | atomic_inc(&nf_bridge->use); |
| 1650 | } |
| 1651 | #endif /* CONFIG_BRIDGE_NETFILTER */ |
Patrick McHardy | a193a4a | 2006-03-20 19:23:05 -0800 | [diff] [blame] | 1652 | static inline void nf_reset(struct sk_buff *skb) |
| 1653 | { |
Yasuyuki Kozakai | 5f79e0f | 2007-03-23 11:17:07 -0700 | [diff] [blame] | 1654 | #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE) |
Patrick McHardy | a193a4a | 2006-03-20 19:23:05 -0800 | [diff] [blame] | 1655 | nf_conntrack_put(skb->nfct); |
| 1656 | skb->nfct = NULL; |
Patrick McHardy | a193a4a | 2006-03-20 19:23:05 -0800 | [diff] [blame] | 1657 | nf_conntrack_put_reasm(skb->nfct_reasm); |
| 1658 | skb->nfct_reasm = NULL; |
| 1659 | #endif |
| 1660 | #ifdef CONFIG_BRIDGE_NETFILTER |
| 1661 | nf_bridge_put(skb->nf_bridge); |
| 1662 | skb->nf_bridge = NULL; |
| 1663 | #endif |
| 1664 | } |
| 1665 | |
Yasuyuki Kozakai | edda553 | 2007-03-14 16:43:37 -0700 | [diff] [blame] | 1666 | /* Note: This doesn't put any conntrack and bridge info in dst. */ |
| 1667 | static inline void __nf_copy(struct sk_buff *dst, const struct sk_buff *src) |
| 1668 | { |
Yasuyuki Kozakai | 5f79e0f | 2007-03-23 11:17:07 -0700 | [diff] [blame] | 1669 | #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE) |
Yasuyuki Kozakai | edda553 | 2007-03-14 16:43:37 -0700 | [diff] [blame] | 1670 | dst->nfct = src->nfct; |
| 1671 | nf_conntrack_get(src->nfct); |
| 1672 | dst->nfctinfo = src->nfctinfo; |
Yasuyuki Kozakai | edda553 | 2007-03-14 16:43:37 -0700 | [diff] [blame] | 1673 | dst->nfct_reasm = src->nfct_reasm; |
| 1674 | nf_conntrack_get_reasm(src->nfct_reasm); |
| 1675 | #endif |
| 1676 | #ifdef CONFIG_BRIDGE_NETFILTER |
| 1677 | dst->nf_bridge = src->nf_bridge; |
| 1678 | nf_bridge_get(src->nf_bridge); |
| 1679 | #endif |
| 1680 | } |
| 1681 | |
Yasuyuki Kozakai | e7ac05f | 2007-03-14 16:44:01 -0700 | [diff] [blame] | 1682 | static inline void nf_copy(struct sk_buff *dst, const struct sk_buff *src) |
| 1683 | { |
Yasuyuki Kozakai | e7ac05f | 2007-03-14 16:44:01 -0700 | [diff] [blame] | 1684 | #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE) |
Yasuyuki Kozakai | 5f79e0f | 2007-03-23 11:17:07 -0700 | [diff] [blame] | 1685 | nf_conntrack_put(dst->nfct); |
Yasuyuki Kozakai | e7ac05f | 2007-03-14 16:44:01 -0700 | [diff] [blame] | 1686 | nf_conntrack_put_reasm(dst->nfct_reasm); |
| 1687 | #endif |
| 1688 | #ifdef CONFIG_BRIDGE_NETFILTER |
| 1689 | nf_bridge_put(dst->nf_bridge); |
| 1690 | #endif |
| 1691 | __nf_copy(dst, src); |
| 1692 | } |
| 1693 | |
James Morris | 984bc16 | 2006-06-09 00:29:17 -0700 | [diff] [blame] | 1694 | #ifdef CONFIG_NETWORK_SECMARK |
| 1695 | static inline void skb_copy_secmark(struct sk_buff *to, const struct sk_buff *from) |
| 1696 | { |
| 1697 | to->secmark = from->secmark; |
| 1698 | } |
| 1699 | |
| 1700 | static inline void skb_init_secmark(struct sk_buff *skb) |
| 1701 | { |
| 1702 | skb->secmark = 0; |
| 1703 | } |
| 1704 | #else |
| 1705 | static inline void skb_copy_secmark(struct sk_buff *to, const struct sk_buff *from) |
| 1706 | { } |
| 1707 | |
| 1708 | static inline void skb_init_secmark(struct sk_buff *skb) |
| 1709 | { } |
| 1710 | #endif |
| 1711 | |
Herbert Xu | 89114af | 2006-07-08 13:34:32 -0700 | [diff] [blame] | 1712 | static inline int skb_is_gso(const struct sk_buff *skb) |
| 1713 | { |
| 1714 | return skb_shinfo(skb)->gso_size; |
| 1715 | } |
| 1716 | |
Herbert Xu | 35fc92a | 2007-03-26 23:22:20 -0700 | [diff] [blame] | 1717 | static inline void skb_forward_csum(struct sk_buff *skb) |
| 1718 | { |
| 1719 | /* Unfortunately we don't support this one. Any brave souls? */ |
| 1720 | if (skb->ip_summed == CHECKSUM_COMPLETE) |
| 1721 | skb->ip_summed = CHECKSUM_NONE; |
| 1722 | } |
| 1723 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1724 | #endif /* __KERNEL__ */ |
| 1725 | #endif /* _LINUX_SKBUFF_H */ |