Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * Routines having to do with the 'struct sk_buff' memory handlers. |
| 3 | * |
Alan Cox | 113aa83 | 2008-10-13 19:01:08 -0700 | [diff] [blame] | 4 | * Authors: Alan Cox <alan@lxorguk.ukuu.org.uk> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 5 | * Florian La Roche <rzsfl@rz.uni-sb.de> |
| 6 | * |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 7 | * Fixes: |
| 8 | * Alan Cox : Fixed the worst of the load |
| 9 | * balancer bugs. |
| 10 | * Dave Platt : Interrupt stacking fix. |
| 11 | * Richard Kooijman : Timestamp fixes. |
| 12 | * Alan Cox : Changed buffer format. |
| 13 | * Alan Cox : destructor hook for AF_UNIX etc. |
| 14 | * Linus Torvalds : Better skb_clone. |
| 15 | * Alan Cox : Added skb_copy. |
| 16 | * Alan Cox : Added all the changed routines Linus |
| 17 | * only put in the headers |
| 18 | * Ray VanTassle : Fixed --skb->lock in free |
| 19 | * Alan Cox : skb_copy copy arp field |
| 20 | * Andi Kleen : slabified it. |
| 21 | * Robert Olsson : Removed skb_head_pool |
| 22 | * |
| 23 | * NOTE: |
| 24 | * The __skb_ routines should be called with interrupts |
| 25 | * disabled, or you better be *real* sure that the operation is atomic |
| 26 | * with respect to whatever list is being frobbed (e.g. via lock_sock() |
| 27 | * or via disabling bottom half handlers, etc). |
| 28 | * |
| 29 | * This program is free software; you can redistribute it and/or |
| 30 | * modify it under the terms of the GNU General Public License |
| 31 | * as published by the Free Software Foundation; either version |
| 32 | * 2 of the License, or (at your option) any later version. |
| 33 | */ |
| 34 | |
| 35 | /* |
| 36 | * The functions in this file will not compile correctly with gcc 2.4.x |
| 37 | */ |
| 38 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 39 | #include <linux/module.h> |
| 40 | #include <linux/types.h> |
| 41 | #include <linux/kernel.h> |
Vegard Nossum | fe55f6d | 2008-08-30 12:16:35 +0200 | [diff] [blame] | 42 | #include <linux/kmemcheck.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 43 | #include <linux/mm.h> |
| 44 | #include <linux/interrupt.h> |
| 45 | #include <linux/in.h> |
| 46 | #include <linux/inet.h> |
| 47 | #include <linux/slab.h> |
| 48 | #include <linux/netdevice.h> |
| 49 | #ifdef CONFIG_NET_CLS_ACT |
| 50 | #include <net/pkt_sched.h> |
| 51 | #endif |
| 52 | #include <linux/string.h> |
| 53 | #include <linux/skbuff.h> |
Jens Axboe | 9c55e01 | 2007-11-06 23:30:13 -0800 | [diff] [blame] | 54 | #include <linux/splice.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 55 | #include <linux/cache.h> |
| 56 | #include <linux/rtnetlink.h> |
| 57 | #include <linux/init.h> |
David Howells | 716ea3a | 2007-04-02 20:19:53 -0700 | [diff] [blame] | 58 | #include <linux/scatterlist.h> |
Patrick Ohly | ac45f60 | 2009-02-12 05:03:37 +0000 | [diff] [blame] | 59 | #include <linux/errqueue.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 60 | |
| 61 | #include <net/protocol.h> |
| 62 | #include <net/dst.h> |
| 63 | #include <net/sock.h> |
| 64 | #include <net/checksum.h> |
| 65 | #include <net/xfrm.h> |
| 66 | |
| 67 | #include <asm/uaccess.h> |
| 68 | #include <asm/system.h> |
Steven Rostedt | ad8d75f | 2009-04-14 19:39:12 -0400 | [diff] [blame] | 69 | #include <trace/events/skb.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 70 | |
Al Viro | a1f8e7f7 | 2006-10-19 16:08:53 -0400 | [diff] [blame] | 71 | #include "kmap_skb.h" |
| 72 | |
Christoph Lameter | e18b890 | 2006-12-06 20:33:20 -0800 | [diff] [blame] | 73 | static struct kmem_cache *skbuff_head_cache __read_mostly; |
| 74 | static struct kmem_cache *skbuff_fclone_cache __read_mostly; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 75 | |
Jens Axboe | 9c55e01 | 2007-11-06 23:30:13 -0800 | [diff] [blame] | 76 | static void sock_pipe_buf_release(struct pipe_inode_info *pipe, |
| 77 | struct pipe_buffer *buf) |
| 78 | { |
Jarek Poplawski | 8b9d372 | 2009-01-19 17:03:56 -0800 | [diff] [blame] | 79 | put_page(buf->page); |
Jens Axboe | 9c55e01 | 2007-11-06 23:30:13 -0800 | [diff] [blame] | 80 | } |
| 81 | |
| 82 | static void sock_pipe_buf_get(struct pipe_inode_info *pipe, |
| 83 | struct pipe_buffer *buf) |
| 84 | { |
Jarek Poplawski | 8b9d372 | 2009-01-19 17:03:56 -0800 | [diff] [blame] | 85 | get_page(buf->page); |
Jens Axboe | 9c55e01 | 2007-11-06 23:30:13 -0800 | [diff] [blame] | 86 | } |
| 87 | |
| 88 | static int sock_pipe_buf_steal(struct pipe_inode_info *pipe, |
| 89 | struct pipe_buffer *buf) |
| 90 | { |
| 91 | return 1; |
| 92 | } |
| 93 | |
| 94 | |
| 95 | /* Pipe buffer operations for a socket. */ |
Alexey Dobriyan | 28dfef8 | 2009-12-15 16:46:48 -0800 | [diff] [blame] | 96 | static const struct pipe_buf_operations sock_pipe_buf_ops = { |
Jens Axboe | 9c55e01 | 2007-11-06 23:30:13 -0800 | [diff] [blame] | 97 | .can_merge = 0, |
| 98 | .map = generic_pipe_buf_map, |
| 99 | .unmap = generic_pipe_buf_unmap, |
| 100 | .confirm = generic_pipe_buf_confirm, |
| 101 | .release = sock_pipe_buf_release, |
| 102 | .steal = sock_pipe_buf_steal, |
| 103 | .get = sock_pipe_buf_get, |
| 104 | }; |
| 105 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 106 | /* |
| 107 | * Keep out-of-line to prevent kernel bloat. |
| 108 | * __builtin_return_address is not used because it is not always |
| 109 | * reliable. |
| 110 | */ |
| 111 | |
| 112 | /** |
| 113 | * skb_over_panic - private function |
| 114 | * @skb: buffer |
| 115 | * @sz: size |
| 116 | * @here: address |
| 117 | * |
| 118 | * Out of line support code for skb_put(). Not user callable. |
| 119 | */ |
Rami Rosen | ccb7c77 | 2010-04-20 22:39:53 -0700 | [diff] [blame] | 120 | static void skb_over_panic(struct sk_buff *skb, int sz, void *here) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 121 | { |
Patrick McHardy | 2609545 | 2005-04-21 16:43:02 -0700 | [diff] [blame] | 122 | printk(KERN_EMERG "skb_over_panic: text:%p len:%d put:%d head:%p " |
Arnaldo Carvalho de Melo | 4305b54 | 2007-04-19 20:43:29 -0700 | [diff] [blame] | 123 | "data:%p tail:%#lx end:%#lx dev:%s\n", |
Arnaldo Carvalho de Melo | 27a884d | 2007-04-19 20:29:13 -0700 | [diff] [blame] | 124 | here, skb->len, sz, skb->head, skb->data, |
Arnaldo Carvalho de Melo | 4305b54 | 2007-04-19 20:43:29 -0700 | [diff] [blame] | 125 | (unsigned long)skb->tail, (unsigned long)skb->end, |
Patrick McHardy | 2609545 | 2005-04-21 16:43:02 -0700 | [diff] [blame] | 126 | skb->dev ? skb->dev->name : "<NULL>"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 127 | BUG(); |
| 128 | } |
| 129 | |
| 130 | /** |
| 131 | * skb_under_panic - private function |
| 132 | * @skb: buffer |
| 133 | * @sz: size |
| 134 | * @here: address |
| 135 | * |
| 136 | * Out of line support code for skb_push(). Not user callable. |
| 137 | */ |
| 138 | |
Rami Rosen | ccb7c77 | 2010-04-20 22:39:53 -0700 | [diff] [blame] | 139 | static void skb_under_panic(struct sk_buff *skb, int sz, void *here) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 140 | { |
Patrick McHardy | 2609545 | 2005-04-21 16:43:02 -0700 | [diff] [blame] | 141 | printk(KERN_EMERG "skb_under_panic: text:%p len:%d put:%d head:%p " |
Arnaldo Carvalho de Melo | 4305b54 | 2007-04-19 20:43:29 -0700 | [diff] [blame] | 142 | "data:%p tail:%#lx end:%#lx dev:%s\n", |
Arnaldo Carvalho de Melo | 27a884d | 2007-04-19 20:29:13 -0700 | [diff] [blame] | 143 | here, skb->len, sz, skb->head, skb->data, |
Arnaldo Carvalho de Melo | 4305b54 | 2007-04-19 20:43:29 -0700 | [diff] [blame] | 144 | (unsigned long)skb->tail, (unsigned long)skb->end, |
Patrick McHardy | 2609545 | 2005-04-21 16:43:02 -0700 | [diff] [blame] | 145 | skb->dev ? skb->dev->name : "<NULL>"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 146 | BUG(); |
| 147 | } |
| 148 | |
| 149 | /* Allocate a new skbuff. We do this ourselves so we can fill in a few |
| 150 | * 'private' fields and also do memory statistics to find all the |
| 151 | * [BEEP] leaks. |
| 152 | * |
| 153 | */ |
| 154 | |
| 155 | /** |
David S. Miller | d179cd1 | 2005-08-17 14:57:30 -0700 | [diff] [blame] | 156 | * __alloc_skb - allocate a network buffer |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 157 | * @size: size to allocate |
| 158 | * @gfp_mask: allocation mask |
Randy Dunlap | c83c248 | 2005-10-18 22:07:41 -0700 | [diff] [blame] | 159 | * @fclone: allocate from fclone cache instead of head cache |
| 160 | * and allocate a cloned (child) skb |
Christoph Hellwig | b30973f | 2006-12-06 20:32:36 -0800 | [diff] [blame] | 161 | * @node: numa node to allocate memory on |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 162 | * |
| 163 | * Allocate a new &sk_buff. The returned buffer has no headroom and a |
| 164 | * tail room of size bytes. The object has a reference count of one. |
| 165 | * The return is the buffer. On a failure the return is %NULL. |
| 166 | * |
| 167 | * Buffers may only be allocated from interrupts using a @gfp_mask of |
| 168 | * %GFP_ATOMIC. |
| 169 | */ |
Al Viro | dd0fc66 | 2005-10-07 07:46:04 +0100 | [diff] [blame] | 170 | struct sk_buff *__alloc_skb(unsigned int size, gfp_t gfp_mask, |
Christoph Hellwig | b30973f | 2006-12-06 20:32:36 -0800 | [diff] [blame] | 171 | int fclone, int node) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 172 | { |
Christoph Lameter | e18b890 | 2006-12-06 20:33:20 -0800 | [diff] [blame] | 173 | struct kmem_cache *cache; |
Benjamin LaHaise | 4947d3e | 2006-01-03 14:06:50 -0800 | [diff] [blame] | 174 | struct skb_shared_info *shinfo; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 175 | struct sk_buff *skb; |
| 176 | u8 *data; |
| 177 | |
Herbert Xu | 8798b3f | 2006-01-23 16:32:45 -0800 | [diff] [blame] | 178 | cache = fclone ? skbuff_fclone_cache : skbuff_head_cache; |
| 179 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 180 | /* Get the HEAD */ |
Christoph Hellwig | b30973f | 2006-12-06 20:32:36 -0800 | [diff] [blame] | 181 | skb = kmem_cache_alloc_node(cache, gfp_mask & ~__GFP_DMA, node); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 182 | if (!skb) |
| 183 | goto out; |
Eric Dumazet | ec7d2f2 | 2010-05-05 01:07:37 -0700 | [diff] [blame] | 184 | prefetchw(skb); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 185 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 186 | size = SKB_DATA_ALIGN(size); |
Christoph Hellwig | b30973f | 2006-12-06 20:32:36 -0800 | [diff] [blame] | 187 | data = kmalloc_node_track_caller(size + sizeof(struct skb_shared_info), |
| 188 | gfp_mask, node); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 189 | if (!data) |
| 190 | goto nodata; |
Eric Dumazet | ec7d2f2 | 2010-05-05 01:07:37 -0700 | [diff] [blame] | 191 | prefetchw(data + size); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 192 | |
Arnaldo Carvalho de Melo | ca0605a | 2007-03-19 10:48:59 -0300 | [diff] [blame] | 193 | /* |
Johannes Berg | c800578 | 2008-05-03 20:56:42 -0700 | [diff] [blame] | 194 | * Only clear those fields we need to clear, not those that we will |
| 195 | * actually initialise below. Hence, don't put any more fields after |
| 196 | * the tail pointer in struct sk_buff! |
Arnaldo Carvalho de Melo | ca0605a | 2007-03-19 10:48:59 -0300 | [diff] [blame] | 197 | */ |
| 198 | memset(skb, 0, offsetof(struct sk_buff, tail)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 199 | skb->truesize = size + sizeof(struct sk_buff); |
| 200 | atomic_set(&skb->users, 1); |
| 201 | skb->head = data; |
| 202 | skb->data = data; |
Arnaldo Carvalho de Melo | 27a884d | 2007-04-19 20:29:13 -0700 | [diff] [blame] | 203 | skb_reset_tail_pointer(skb); |
Arnaldo Carvalho de Melo | 4305b54 | 2007-04-19 20:43:29 -0700 | [diff] [blame] | 204 | skb->end = skb->tail + size; |
Stephen Hemminger | 19633e1 | 2009-06-17 05:23:27 +0000 | [diff] [blame] | 205 | #ifdef NET_SKBUFF_DATA_USES_OFFSET |
| 206 | skb->mac_header = ~0U; |
| 207 | #endif |
| 208 | |
Benjamin LaHaise | 4947d3e | 2006-01-03 14:06:50 -0800 | [diff] [blame] | 209 | /* make sure we initialize shinfo sequentially */ |
| 210 | shinfo = skb_shinfo(skb); |
Eric Dumazet | ec7d2f2 | 2010-05-05 01:07:37 -0700 | [diff] [blame] | 211 | memset(shinfo, 0, offsetof(struct skb_shared_info, dataref)); |
Benjamin LaHaise | 4947d3e | 2006-01-03 14:06:50 -0800 | [diff] [blame] | 212 | atomic_set(&shinfo->dataref, 1); |
Benjamin LaHaise | 4947d3e | 2006-01-03 14:06:50 -0800 | [diff] [blame] | 213 | |
David S. Miller | d179cd1 | 2005-08-17 14:57:30 -0700 | [diff] [blame] | 214 | if (fclone) { |
| 215 | struct sk_buff *child = skb + 1; |
| 216 | atomic_t *fclone_ref = (atomic_t *) (child + 1); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 217 | |
Vegard Nossum | fe55f6d | 2008-08-30 12:16:35 +0200 | [diff] [blame] | 218 | kmemcheck_annotate_bitfield(child, flags1); |
| 219 | kmemcheck_annotate_bitfield(child, flags2); |
David S. Miller | d179cd1 | 2005-08-17 14:57:30 -0700 | [diff] [blame] | 220 | skb->fclone = SKB_FCLONE_ORIG; |
| 221 | atomic_set(fclone_ref, 1); |
| 222 | |
| 223 | child->fclone = SKB_FCLONE_UNAVAILABLE; |
| 224 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 225 | out: |
| 226 | return skb; |
| 227 | nodata: |
Herbert Xu | 8798b3f | 2006-01-23 16:32:45 -0800 | [diff] [blame] | 228 | kmem_cache_free(cache, skb); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 229 | skb = NULL; |
| 230 | goto out; |
| 231 | } |
David S. Miller | b4ac530fc | 2009-02-10 02:09:24 -0800 | [diff] [blame] | 232 | EXPORT_SYMBOL(__alloc_skb); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 233 | |
| 234 | /** |
Christoph Hellwig | 8af2745 | 2006-07-31 22:35:23 -0700 | [diff] [blame] | 235 | * __netdev_alloc_skb - allocate an skbuff for rx on a specific device |
| 236 | * @dev: network device to receive on |
| 237 | * @length: length to allocate |
| 238 | * @gfp_mask: get_free_pages mask, passed to alloc_skb |
| 239 | * |
| 240 | * Allocate a new &sk_buff and assign it a usage count of one. The |
| 241 | * buffer has unspecified headroom built in. Users should allocate |
| 242 | * the headroom they think they need without accounting for the |
| 243 | * built in space. The built in space is used for optimisations. |
| 244 | * |
| 245 | * %NULL is returned if there is no free memory. |
| 246 | */ |
| 247 | struct sk_buff *__netdev_alloc_skb(struct net_device *dev, |
| 248 | unsigned int length, gfp_t gfp_mask) |
| 249 | { |
| 250 | struct sk_buff *skb; |
| 251 | |
Eric Dumazet | 564824b | 2010-10-11 19:05:25 +0000 | [diff] [blame] | 252 | skb = __alloc_skb(length + NET_SKB_PAD, gfp_mask, 0, NUMA_NO_NODE); |
Christoph Hellwig | 7b2e497 | 2006-08-07 16:09:04 -0700 | [diff] [blame] | 253 | if (likely(skb)) { |
Christoph Hellwig | 8af2745 | 2006-07-31 22:35:23 -0700 | [diff] [blame] | 254 | skb_reserve(skb, NET_SKB_PAD); |
Christoph Hellwig | 7b2e497 | 2006-08-07 16:09:04 -0700 | [diff] [blame] | 255 | skb->dev = dev; |
| 256 | } |
Christoph Hellwig | 8af2745 | 2006-07-31 22:35:23 -0700 | [diff] [blame] | 257 | return skb; |
| 258 | } |
David S. Miller | b4ac530fc | 2009-02-10 02:09:24 -0800 | [diff] [blame] | 259 | EXPORT_SYMBOL(__netdev_alloc_skb); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 260 | |
Peter Zijlstra | 654bed1 | 2008-10-07 14:22:33 -0700 | [diff] [blame] | 261 | void skb_add_rx_frag(struct sk_buff *skb, int i, struct page *page, int off, |
| 262 | int size) |
| 263 | { |
| 264 | skb_fill_page_desc(skb, i, page, off, size); |
| 265 | skb->len += size; |
| 266 | skb->data_len += size; |
| 267 | skb->truesize += size; |
| 268 | } |
| 269 | EXPORT_SYMBOL(skb_add_rx_frag); |
| 270 | |
Ilpo Järvinen | f58518e | 2008-03-27 17:51:31 -0700 | [diff] [blame] | 271 | /** |
| 272 | * dev_alloc_skb - allocate an skbuff for receiving |
| 273 | * @length: length to allocate |
| 274 | * |
| 275 | * Allocate a new &sk_buff and assign it a usage count of one. The |
| 276 | * buffer has unspecified headroom built in. Users should allocate |
| 277 | * the headroom they think they need without accounting for the |
| 278 | * built in space. The built in space is used for optimisations. |
| 279 | * |
| 280 | * %NULL is returned if there is no free memory. Although this function |
| 281 | * allocates memory it can be called from an interrupt. |
| 282 | */ |
| 283 | struct sk_buff *dev_alloc_skb(unsigned int length) |
| 284 | { |
Denys Vlasenko | 1483b87 | 2008-03-28 15:57:39 -0700 | [diff] [blame] | 285 | /* |
| 286 | * There is more code here than it seems: |
David S. Miller | a0f55e0 | 2008-03-28 18:22:32 -0700 | [diff] [blame] | 287 | * __dev_alloc_skb is an inline |
Denys Vlasenko | 1483b87 | 2008-03-28 15:57:39 -0700 | [diff] [blame] | 288 | */ |
Ilpo Järvinen | f58518e | 2008-03-27 17:51:31 -0700 | [diff] [blame] | 289 | return __dev_alloc_skb(length, GFP_ATOMIC); |
| 290 | } |
| 291 | EXPORT_SYMBOL(dev_alloc_skb); |
| 292 | |
Herbert Xu | 27b437c | 2006-07-13 19:26:39 -0700 | [diff] [blame] | 293 | static void skb_drop_list(struct sk_buff **listp) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 294 | { |
Herbert Xu | 27b437c | 2006-07-13 19:26:39 -0700 | [diff] [blame] | 295 | struct sk_buff *list = *listp; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 296 | |
Herbert Xu | 27b437c | 2006-07-13 19:26:39 -0700 | [diff] [blame] | 297 | *listp = NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 298 | |
| 299 | do { |
| 300 | struct sk_buff *this = list; |
| 301 | list = list->next; |
| 302 | kfree_skb(this); |
| 303 | } while (list); |
| 304 | } |
| 305 | |
Herbert Xu | 27b437c | 2006-07-13 19:26:39 -0700 | [diff] [blame] | 306 | static inline void skb_drop_fraglist(struct sk_buff *skb) |
| 307 | { |
| 308 | skb_drop_list(&skb_shinfo(skb)->frag_list); |
| 309 | } |
| 310 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 311 | static void skb_clone_fraglist(struct sk_buff *skb) |
| 312 | { |
| 313 | struct sk_buff *list; |
| 314 | |
David S. Miller | fbb398a | 2009-06-09 00:18:59 -0700 | [diff] [blame] | 315 | skb_walk_frags(skb, list) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 316 | skb_get(list); |
| 317 | } |
| 318 | |
Adrian Bunk | 5bba171 | 2006-06-29 13:02:35 -0700 | [diff] [blame] | 319 | static void skb_release_data(struct sk_buff *skb) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 320 | { |
| 321 | if (!skb->cloned || |
| 322 | !atomic_sub_return(skb->nohdr ? (1 << SKB_DATAREF_SHIFT) + 1 : 1, |
| 323 | &skb_shinfo(skb)->dataref)) { |
| 324 | if (skb_shinfo(skb)->nr_frags) { |
| 325 | int i; |
| 326 | for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) |
| 327 | put_page(skb_shinfo(skb)->frags[i].page); |
| 328 | } |
| 329 | |
David S. Miller | 21dc330 | 2010-08-23 00:13:46 -0700 | [diff] [blame] | 330 | if (skb_has_frag_list(skb)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 331 | skb_drop_fraglist(skb); |
| 332 | |
| 333 | kfree(skb->head); |
| 334 | } |
| 335 | } |
| 336 | |
| 337 | /* |
| 338 | * Free an skbuff by memory without cleaning the state. |
| 339 | */ |
Herbert Xu | 2d4baff | 2007-11-26 23:11:19 +0800 | [diff] [blame] | 340 | static void kfree_skbmem(struct sk_buff *skb) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 341 | { |
David S. Miller | d179cd1 | 2005-08-17 14:57:30 -0700 | [diff] [blame] | 342 | struct sk_buff *other; |
| 343 | atomic_t *fclone_ref; |
| 344 | |
David S. Miller | d179cd1 | 2005-08-17 14:57:30 -0700 | [diff] [blame] | 345 | switch (skb->fclone) { |
| 346 | case SKB_FCLONE_UNAVAILABLE: |
| 347 | kmem_cache_free(skbuff_head_cache, skb); |
| 348 | break; |
| 349 | |
| 350 | case SKB_FCLONE_ORIG: |
| 351 | fclone_ref = (atomic_t *) (skb + 2); |
| 352 | if (atomic_dec_and_test(fclone_ref)) |
| 353 | kmem_cache_free(skbuff_fclone_cache, skb); |
| 354 | break; |
| 355 | |
| 356 | case SKB_FCLONE_CLONE: |
| 357 | fclone_ref = (atomic_t *) (skb + 1); |
| 358 | other = skb - 1; |
| 359 | |
| 360 | /* The clone portion is available for |
| 361 | * fast-cloning again. |
| 362 | */ |
| 363 | skb->fclone = SKB_FCLONE_UNAVAILABLE; |
| 364 | |
| 365 | if (atomic_dec_and_test(fclone_ref)) |
| 366 | kmem_cache_free(skbuff_fclone_cache, other); |
| 367 | break; |
Stephen Hemminger | 3ff50b7 | 2007-04-20 17:09:22 -0700 | [diff] [blame] | 368 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 369 | } |
| 370 | |
Lennert Buytenhek | 04a4bb5 | 2008-10-01 02:33:12 -0700 | [diff] [blame] | 371 | static void skb_release_head_state(struct sk_buff *skb) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 372 | { |
Eric Dumazet | adf3090 | 2009-06-02 05:19:30 +0000 | [diff] [blame] | 373 | skb_dst_drop(skb); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 374 | #ifdef CONFIG_XFRM |
| 375 | secpath_put(skb->sp); |
| 376 | #endif |
Stephen Hemminger | 9c2b332 | 2005-04-19 22:39:42 -0700 | [diff] [blame] | 377 | if (skb->destructor) { |
| 378 | WARN_ON(in_irq()); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 379 | skb->destructor(skb); |
| 380 | } |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 381 | #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE) |
Yasuyuki Kozakai | 5f79e0f | 2007-03-23 11:17:07 -0700 | [diff] [blame] | 382 | nf_conntrack_put(skb->nfct); |
KOVACS Krisztian | 2fc72c7 | 2011-01-12 20:25:08 +0100 | [diff] [blame] | 383 | #endif |
| 384 | #ifdef NET_SKBUFF_NF_DEFRAG_NEEDED |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 385 | nf_conntrack_put_reasm(skb->nfct_reasm); |
| 386 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 387 | #ifdef CONFIG_BRIDGE_NETFILTER |
| 388 | nf_bridge_put(skb->nf_bridge); |
| 389 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 390 | /* XXX: IS this still necessary? - JHS */ |
| 391 | #ifdef CONFIG_NET_SCHED |
| 392 | skb->tc_index = 0; |
| 393 | #ifdef CONFIG_NET_CLS_ACT |
| 394 | skb->tc_verd = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 395 | #endif |
| 396 | #endif |
Lennert Buytenhek | 04a4bb5 | 2008-10-01 02:33:12 -0700 | [diff] [blame] | 397 | } |
| 398 | |
| 399 | /* Free everything but the sk_buff shell. */ |
| 400 | static void skb_release_all(struct sk_buff *skb) |
| 401 | { |
| 402 | skb_release_head_state(skb); |
Herbert Xu | 2d4baff | 2007-11-26 23:11:19 +0800 | [diff] [blame] | 403 | skb_release_data(skb); |
| 404 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 405 | |
Herbert Xu | 2d4baff | 2007-11-26 23:11:19 +0800 | [diff] [blame] | 406 | /** |
| 407 | * __kfree_skb - private function |
| 408 | * @skb: buffer |
| 409 | * |
| 410 | * Free an sk_buff. Release anything attached to the buffer. |
| 411 | * Clean the state. This is an internal helper function. Users should |
| 412 | * always call kfree_skb |
| 413 | */ |
| 414 | |
| 415 | void __kfree_skb(struct sk_buff *skb) |
| 416 | { |
| 417 | skb_release_all(skb); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 418 | kfree_skbmem(skb); |
| 419 | } |
David S. Miller | b4ac530fc | 2009-02-10 02:09:24 -0800 | [diff] [blame] | 420 | EXPORT_SYMBOL(__kfree_skb); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 421 | |
| 422 | /** |
Jörn Engel | 231d06a | 2006-03-20 21:28:35 -0800 | [diff] [blame] | 423 | * kfree_skb - free an sk_buff |
| 424 | * @skb: buffer to free |
| 425 | * |
| 426 | * Drop a reference to the buffer and free it if the usage count has |
| 427 | * hit zero. |
| 428 | */ |
| 429 | void kfree_skb(struct sk_buff *skb) |
| 430 | { |
| 431 | if (unlikely(!skb)) |
| 432 | return; |
| 433 | if (likely(atomic_read(&skb->users) == 1)) |
| 434 | smp_rmb(); |
| 435 | else if (likely(!atomic_dec_and_test(&skb->users))) |
| 436 | return; |
Neil Horman | ead2ceb | 2009-03-11 09:49:55 +0000 | [diff] [blame] | 437 | trace_kfree_skb(skb, __builtin_return_address(0)); |
Jörn Engel | 231d06a | 2006-03-20 21:28:35 -0800 | [diff] [blame] | 438 | __kfree_skb(skb); |
| 439 | } |
David S. Miller | b4ac530fc | 2009-02-10 02:09:24 -0800 | [diff] [blame] | 440 | EXPORT_SYMBOL(kfree_skb); |
Jörn Engel | 231d06a | 2006-03-20 21:28:35 -0800 | [diff] [blame] | 441 | |
Stephen Hemminger | d1a203e | 2008-11-01 21:01:09 -0700 | [diff] [blame] | 442 | /** |
Neil Horman | ead2ceb | 2009-03-11 09:49:55 +0000 | [diff] [blame] | 443 | * consume_skb - free an skbuff |
| 444 | * @skb: buffer to free |
| 445 | * |
| 446 | * Drop a ref to the buffer and free it if the usage count has hit zero |
| 447 | * Functions identically to kfree_skb, but kfree_skb assumes that the frame |
| 448 | * is being dropped after a failure and notes that |
| 449 | */ |
| 450 | void consume_skb(struct sk_buff *skb) |
| 451 | { |
| 452 | if (unlikely(!skb)) |
| 453 | return; |
| 454 | if (likely(atomic_read(&skb->users) == 1)) |
| 455 | smp_rmb(); |
| 456 | else if (likely(!atomic_dec_and_test(&skb->users))) |
| 457 | return; |
Koki Sanagi | 07dc22e | 2010-08-23 18:46:12 +0900 | [diff] [blame] | 458 | trace_consume_skb(skb); |
Neil Horman | ead2ceb | 2009-03-11 09:49:55 +0000 | [diff] [blame] | 459 | __kfree_skb(skb); |
| 460 | } |
| 461 | EXPORT_SYMBOL(consume_skb); |
| 462 | |
| 463 | /** |
Stephen Hemminger | d1a203e | 2008-11-01 21:01:09 -0700 | [diff] [blame] | 464 | * skb_recycle_check - check if skb can be reused for receive |
| 465 | * @skb: buffer |
| 466 | * @skb_size: minimum receive buffer size |
| 467 | * |
| 468 | * Checks that the skb passed in is not shared or cloned, and |
| 469 | * that it is linear and its head portion at least as large as |
| 470 | * skb_size so that it can be recycled as a receive buffer. |
| 471 | * If these conditions are met, this function does any necessary |
| 472 | * reference count dropping and cleans up the skbuff as if it |
| 473 | * just came from __alloc_skb(). |
| 474 | */ |
Changli Gao | 5b0daa3 | 2010-05-29 00:12:13 -0700 | [diff] [blame] | 475 | bool skb_recycle_check(struct sk_buff *skb, int skb_size) |
Lennert Buytenhek | 04a4bb5 | 2008-10-01 02:33:12 -0700 | [diff] [blame] | 476 | { |
| 477 | struct skb_shared_info *shinfo; |
| 478 | |
Anton Vorontsov | e84af6d | 2009-11-10 14:11:01 +0000 | [diff] [blame] | 479 | if (irqs_disabled()) |
Changli Gao | 5b0daa3 | 2010-05-29 00:12:13 -0700 | [diff] [blame] | 480 | return false; |
Anton Vorontsov | e84af6d | 2009-11-10 14:11:01 +0000 | [diff] [blame] | 481 | |
Lennert Buytenhek | 04a4bb5 | 2008-10-01 02:33:12 -0700 | [diff] [blame] | 482 | if (skb_is_nonlinear(skb) || skb->fclone != SKB_FCLONE_UNAVAILABLE) |
Changli Gao | 5b0daa3 | 2010-05-29 00:12:13 -0700 | [diff] [blame] | 483 | return false; |
Lennert Buytenhek | 04a4bb5 | 2008-10-01 02:33:12 -0700 | [diff] [blame] | 484 | |
| 485 | skb_size = SKB_DATA_ALIGN(skb_size + NET_SKB_PAD); |
| 486 | if (skb_end_pointer(skb) - skb->head < skb_size) |
Changli Gao | 5b0daa3 | 2010-05-29 00:12:13 -0700 | [diff] [blame] | 487 | return false; |
Lennert Buytenhek | 04a4bb5 | 2008-10-01 02:33:12 -0700 | [diff] [blame] | 488 | |
| 489 | if (skb_shared(skb) || skb_cloned(skb)) |
Changli Gao | 5b0daa3 | 2010-05-29 00:12:13 -0700 | [diff] [blame] | 490 | return false; |
Lennert Buytenhek | 04a4bb5 | 2008-10-01 02:33:12 -0700 | [diff] [blame] | 491 | |
| 492 | skb_release_head_state(skb); |
Eric Dumazet | ec7d2f2 | 2010-05-05 01:07:37 -0700 | [diff] [blame] | 493 | |
Lennert Buytenhek | 04a4bb5 | 2008-10-01 02:33:12 -0700 | [diff] [blame] | 494 | shinfo = skb_shinfo(skb); |
Eric Dumazet | ec7d2f2 | 2010-05-05 01:07:37 -0700 | [diff] [blame] | 495 | memset(shinfo, 0, offsetof(struct skb_shared_info, dataref)); |
Lennert Buytenhek | 04a4bb5 | 2008-10-01 02:33:12 -0700 | [diff] [blame] | 496 | atomic_set(&shinfo->dataref, 1); |
Lennert Buytenhek | 04a4bb5 | 2008-10-01 02:33:12 -0700 | [diff] [blame] | 497 | |
| 498 | memset(skb, 0, offsetof(struct sk_buff, tail)); |
Lennert Buytenhek | 04a4bb5 | 2008-10-01 02:33:12 -0700 | [diff] [blame] | 499 | skb->data = skb->head + NET_SKB_PAD; |
Lennert Buytenhek | 5cd33db | 2008-11-10 21:45:05 -0800 | [diff] [blame] | 500 | skb_reset_tail_pointer(skb); |
Lennert Buytenhek | 04a4bb5 | 2008-10-01 02:33:12 -0700 | [diff] [blame] | 501 | |
Changli Gao | 5b0daa3 | 2010-05-29 00:12:13 -0700 | [diff] [blame] | 502 | return true; |
Lennert Buytenhek | 04a4bb5 | 2008-10-01 02:33:12 -0700 | [diff] [blame] | 503 | } |
| 504 | EXPORT_SYMBOL(skb_recycle_check); |
| 505 | |
Herbert Xu | dec1881 | 2007-10-14 00:37:30 -0700 | [diff] [blame] | 506 | static void __copy_skb_header(struct sk_buff *new, const struct sk_buff *old) |
| 507 | { |
| 508 | new->tstamp = old->tstamp; |
| 509 | new->dev = old->dev; |
| 510 | new->transport_header = old->transport_header; |
| 511 | new->network_header = old->network_header; |
| 512 | new->mac_header = old->mac_header; |
Eric Dumazet | 7fee226 | 2010-05-11 23:19:48 +0000 | [diff] [blame] | 513 | skb_dst_copy(new, old); |
Tom Herbert | 0a9627f | 2010-03-16 08:03:29 +0000 | [diff] [blame] | 514 | new->rxhash = old->rxhash; |
Alexey Dobriyan | def8b4f | 2008-10-28 13:24:06 -0700 | [diff] [blame] | 515 | #ifdef CONFIG_XFRM |
Herbert Xu | dec1881 | 2007-10-14 00:37:30 -0700 | [diff] [blame] | 516 | new->sp = secpath_get(old->sp); |
| 517 | #endif |
| 518 | memcpy(new->cb, old->cb, sizeof(old->cb)); |
Herbert Xu | 9bcb97c | 2009-05-22 22:20:02 +0000 | [diff] [blame] | 519 | new->csum = old->csum; |
Herbert Xu | dec1881 | 2007-10-14 00:37:30 -0700 | [diff] [blame] | 520 | new->local_df = old->local_df; |
| 521 | new->pkt_type = old->pkt_type; |
| 522 | new->ip_summed = old->ip_summed; |
| 523 | skb_copy_queue_mapping(new, old); |
| 524 | new->priority = old->priority; |
John Fastabend | e897082 | 2010-06-13 10:36:30 +0000 | [diff] [blame] | 525 | new->deliver_no_wcard = old->deliver_no_wcard; |
Herbert Xu | dec1881 | 2007-10-14 00:37:30 -0700 | [diff] [blame] | 526 | #if defined(CONFIG_IP_VS) || defined(CONFIG_IP_VS_MODULE) |
| 527 | new->ipvs_property = old->ipvs_property; |
| 528 | #endif |
| 529 | new->protocol = old->protocol; |
| 530 | new->mark = old->mark; |
Eric Dumazet | 8964be4 | 2009-11-20 15:35:04 -0800 | [diff] [blame] | 531 | new->skb_iif = old->skb_iif; |
Herbert Xu | dec1881 | 2007-10-14 00:37:30 -0700 | [diff] [blame] | 532 | __nf_copy(new, old); |
| 533 | #if defined(CONFIG_NETFILTER_XT_TARGET_TRACE) || \ |
| 534 | defined(CONFIG_NETFILTER_XT_TARGET_TRACE_MODULE) |
| 535 | new->nf_trace = old->nf_trace; |
| 536 | #endif |
| 537 | #ifdef CONFIG_NET_SCHED |
| 538 | new->tc_index = old->tc_index; |
| 539 | #ifdef CONFIG_NET_CLS_ACT |
| 540 | new->tc_verd = old->tc_verd; |
| 541 | #endif |
| 542 | #endif |
Patrick McHardy | 6aa895b0 | 2008-07-14 22:49:06 -0700 | [diff] [blame] | 543 | new->vlan_tci = old->vlan_tci; |
| 544 | |
Herbert Xu | dec1881 | 2007-10-14 00:37:30 -0700 | [diff] [blame] | 545 | skb_copy_secmark(new, old); |
| 546 | } |
| 547 | |
Herbert Xu | 82c49a3 | 2009-05-22 22:11:37 +0000 | [diff] [blame] | 548 | /* |
| 549 | * You should not add any new code to this function. Add it to |
| 550 | * __copy_skb_header above instead. |
| 551 | */ |
Herbert Xu | e0053ec | 2007-10-14 00:37:52 -0700 | [diff] [blame] | 552 | static struct sk_buff *__skb_clone(struct sk_buff *n, struct sk_buff *skb) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 553 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 554 | #define C(x) n->x = skb->x |
| 555 | |
| 556 | n->next = n->prev = NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 557 | n->sk = NULL; |
Herbert Xu | dec1881 | 2007-10-14 00:37:30 -0700 | [diff] [blame] | 558 | __copy_skb_header(n, skb); |
| 559 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 560 | C(len); |
| 561 | C(data_len); |
Alexey Dobriyan | 3e6b3b2 | 2007-03-16 15:00:46 -0700 | [diff] [blame] | 562 | C(mac_len); |
Patrick McHardy | 334a813 | 2007-06-25 04:35:20 -0700 | [diff] [blame] | 563 | n->hdr_len = skb->nohdr ? skb_headroom(skb) : skb->hdr_len; |
Paul Moore | 02f1c89 | 2008-01-07 21:56:41 -0800 | [diff] [blame] | 564 | n->cloned = 1; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 565 | n->nohdr = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 566 | n->destructor = NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 567 | C(tail); |
| 568 | C(end); |
Paul Moore | 02f1c89 | 2008-01-07 21:56:41 -0800 | [diff] [blame] | 569 | C(head); |
| 570 | C(data); |
| 571 | C(truesize); |
| 572 | atomic_set(&n->users, 1); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 573 | |
| 574 | atomic_inc(&(skb_shinfo(skb)->dataref)); |
| 575 | skb->cloned = 1; |
| 576 | |
| 577 | return n; |
Herbert Xu | e0053ec | 2007-10-14 00:37:52 -0700 | [diff] [blame] | 578 | #undef C |
| 579 | } |
| 580 | |
| 581 | /** |
| 582 | * skb_morph - morph one skb into another |
| 583 | * @dst: the skb to receive the contents |
| 584 | * @src: the skb to supply the contents |
| 585 | * |
| 586 | * This is identical to skb_clone except that the target skb is |
| 587 | * supplied by the user. |
| 588 | * |
| 589 | * The target skb is returned upon exit. |
| 590 | */ |
| 591 | struct sk_buff *skb_morph(struct sk_buff *dst, struct sk_buff *src) |
| 592 | { |
Herbert Xu | 2d4baff | 2007-11-26 23:11:19 +0800 | [diff] [blame] | 593 | skb_release_all(dst); |
Herbert Xu | e0053ec | 2007-10-14 00:37:52 -0700 | [diff] [blame] | 594 | return __skb_clone(dst, src); |
| 595 | } |
| 596 | EXPORT_SYMBOL_GPL(skb_morph); |
| 597 | |
| 598 | /** |
| 599 | * skb_clone - duplicate an sk_buff |
| 600 | * @skb: buffer to clone |
| 601 | * @gfp_mask: allocation priority |
| 602 | * |
| 603 | * Duplicate an &sk_buff. The new one is not owned by a socket. Both |
| 604 | * copies share the same packet data but not structure. The new |
| 605 | * buffer has a reference count of 1. If the allocation fails the |
| 606 | * function returns %NULL otherwise the new buffer is returned. |
| 607 | * |
| 608 | * If this function is called from an interrupt gfp_mask() must be |
| 609 | * %GFP_ATOMIC. |
| 610 | */ |
| 611 | |
| 612 | struct sk_buff *skb_clone(struct sk_buff *skb, gfp_t gfp_mask) |
| 613 | { |
| 614 | struct sk_buff *n; |
| 615 | |
| 616 | n = skb + 1; |
| 617 | if (skb->fclone == SKB_FCLONE_ORIG && |
| 618 | n->fclone == SKB_FCLONE_UNAVAILABLE) { |
| 619 | atomic_t *fclone_ref = (atomic_t *) (n + 1); |
| 620 | n->fclone = SKB_FCLONE_CLONE; |
| 621 | atomic_inc(fclone_ref); |
| 622 | } else { |
| 623 | n = kmem_cache_alloc(skbuff_head_cache, gfp_mask); |
| 624 | if (!n) |
| 625 | return NULL; |
Vegard Nossum | fe55f6d | 2008-08-30 12:16:35 +0200 | [diff] [blame] | 626 | |
| 627 | kmemcheck_annotate_bitfield(n, flags1); |
| 628 | kmemcheck_annotate_bitfield(n, flags2); |
Herbert Xu | e0053ec | 2007-10-14 00:37:52 -0700 | [diff] [blame] | 629 | n->fclone = SKB_FCLONE_UNAVAILABLE; |
| 630 | } |
| 631 | |
| 632 | return __skb_clone(n, skb); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 633 | } |
David S. Miller | b4ac530fc | 2009-02-10 02:09:24 -0800 | [diff] [blame] | 634 | EXPORT_SYMBOL(skb_clone); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 635 | |
| 636 | static void copy_skb_header(struct sk_buff *new, const struct sk_buff *old) |
| 637 | { |
Arnaldo Carvalho de Melo | 2e07fa9 | 2007-04-10 21:22:35 -0700 | [diff] [blame] | 638 | #ifndef NET_SKBUFF_DATA_USES_OFFSET |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 639 | /* |
| 640 | * Shift between the two data areas in bytes |
| 641 | */ |
| 642 | unsigned long offset = new->data - old->data; |
Arnaldo Carvalho de Melo | 2e07fa9 | 2007-04-10 21:22:35 -0700 | [diff] [blame] | 643 | #endif |
Herbert Xu | dec1881 | 2007-10-14 00:37:30 -0700 | [diff] [blame] | 644 | |
| 645 | __copy_skb_header(new, old); |
| 646 | |
Arnaldo Carvalho de Melo | 2e07fa9 | 2007-04-10 21:22:35 -0700 | [diff] [blame] | 647 | #ifndef NET_SKBUFF_DATA_USES_OFFSET |
| 648 | /* {transport,network,mac}_header are relative to skb->head */ |
| 649 | new->transport_header += offset; |
| 650 | new->network_header += offset; |
Stephen Hemminger | 603a8bb | 2009-06-17 12:17:34 +0000 | [diff] [blame] | 651 | if (skb_mac_header_was_set(new)) |
| 652 | new->mac_header += offset; |
Arnaldo Carvalho de Melo | 2e07fa9 | 2007-04-10 21:22:35 -0700 | [diff] [blame] | 653 | #endif |
Herbert Xu | 7967168 | 2006-06-22 02:40:14 -0700 | [diff] [blame] | 654 | skb_shinfo(new)->gso_size = skb_shinfo(old)->gso_size; |
| 655 | skb_shinfo(new)->gso_segs = skb_shinfo(old)->gso_segs; |
| 656 | skb_shinfo(new)->gso_type = skb_shinfo(old)->gso_type; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 657 | } |
| 658 | |
| 659 | /** |
| 660 | * skb_copy - create private copy of an sk_buff |
| 661 | * @skb: buffer to copy |
| 662 | * @gfp_mask: allocation priority |
| 663 | * |
| 664 | * Make a copy of both an &sk_buff and its data. This is used when the |
| 665 | * caller wishes to modify the data and needs a private copy of the |
| 666 | * data to alter. Returns %NULL on failure or the pointer to the buffer |
| 667 | * on success. The returned buffer has a reference count of 1. |
| 668 | * |
| 669 | * As by-product this function converts non-linear &sk_buff to linear |
| 670 | * one, so that &sk_buff becomes completely private and caller is allowed |
| 671 | * to modify all the data of returned buffer. This means that this |
| 672 | * function is not recommended for use in circumstances when only |
| 673 | * header is going to be modified. Use pskb_copy() instead. |
| 674 | */ |
| 675 | |
Al Viro | dd0fc66 | 2005-10-07 07:46:04 +0100 | [diff] [blame] | 676 | struct sk_buff *skb_copy(const struct sk_buff *skb, gfp_t gfp_mask) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 677 | { |
Eric Dumazet | 6602ceb | 2010-09-01 05:25:10 +0000 | [diff] [blame] | 678 | int headerlen = skb_headroom(skb); |
| 679 | unsigned int size = (skb_end_pointer(skb) - skb->head) + skb->data_len; |
| 680 | struct sk_buff *n = alloc_skb(size, gfp_mask); |
| 681 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 682 | if (!n) |
| 683 | return NULL; |
| 684 | |
| 685 | /* Set the data pointer */ |
| 686 | skb_reserve(n, headerlen); |
| 687 | /* Set the tail pointer and length */ |
| 688 | skb_put(n, skb->len); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 689 | |
| 690 | if (skb_copy_bits(skb, -headerlen, n->head, headerlen + skb->len)) |
| 691 | BUG(); |
| 692 | |
| 693 | copy_skb_header(n, skb); |
| 694 | return n; |
| 695 | } |
David S. Miller | b4ac530fc | 2009-02-10 02:09:24 -0800 | [diff] [blame] | 696 | EXPORT_SYMBOL(skb_copy); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 697 | |
| 698 | /** |
| 699 | * pskb_copy - create copy of an sk_buff with private head. |
| 700 | * @skb: buffer to copy |
| 701 | * @gfp_mask: allocation priority |
| 702 | * |
| 703 | * Make a copy of both an &sk_buff and part of its data, located |
| 704 | * in header. Fragmented data remain shared. This is used when |
| 705 | * the caller wishes to modify only header of &sk_buff and needs |
| 706 | * private copy of the header to alter. Returns %NULL on failure |
| 707 | * or the pointer to the buffer on success. |
| 708 | * The returned buffer has a reference count of 1. |
| 709 | */ |
| 710 | |
Al Viro | dd0fc66 | 2005-10-07 07:46:04 +0100 | [diff] [blame] | 711 | struct sk_buff *pskb_copy(struct sk_buff *skb, gfp_t gfp_mask) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 712 | { |
Eric Dumazet | 6602ceb | 2010-09-01 05:25:10 +0000 | [diff] [blame] | 713 | unsigned int size = skb_end_pointer(skb) - skb->head; |
| 714 | struct sk_buff *n = alloc_skb(size, gfp_mask); |
| 715 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 716 | if (!n) |
| 717 | goto out; |
| 718 | |
| 719 | /* Set the data pointer */ |
Eric Dumazet | 6602ceb | 2010-09-01 05:25:10 +0000 | [diff] [blame] | 720 | skb_reserve(n, skb_headroom(skb)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 721 | /* Set the tail pointer and length */ |
| 722 | skb_put(n, skb_headlen(skb)); |
| 723 | /* Copy the bytes */ |
Arnaldo Carvalho de Melo | d626f62 | 2007-03-27 18:55:52 -0300 | [diff] [blame] | 724 | skb_copy_from_linear_data(skb, n->data, n->len); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 725 | |
Herbert Xu | 25f484a | 2006-11-07 14:57:15 -0800 | [diff] [blame] | 726 | n->truesize += skb->data_len; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 727 | n->data_len = skb->data_len; |
| 728 | n->len = skb->len; |
| 729 | |
| 730 | if (skb_shinfo(skb)->nr_frags) { |
| 731 | int i; |
| 732 | |
| 733 | for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) { |
| 734 | skb_shinfo(n)->frags[i] = skb_shinfo(skb)->frags[i]; |
| 735 | get_page(skb_shinfo(n)->frags[i].page); |
| 736 | } |
| 737 | skb_shinfo(n)->nr_frags = i; |
| 738 | } |
| 739 | |
David S. Miller | 21dc330 | 2010-08-23 00:13:46 -0700 | [diff] [blame] | 740 | if (skb_has_frag_list(skb)) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 741 | skb_shinfo(n)->frag_list = skb_shinfo(skb)->frag_list; |
| 742 | skb_clone_fraglist(n); |
| 743 | } |
| 744 | |
| 745 | copy_skb_header(n, skb); |
| 746 | out: |
| 747 | return n; |
| 748 | } |
David S. Miller | b4ac530fc | 2009-02-10 02:09:24 -0800 | [diff] [blame] | 749 | EXPORT_SYMBOL(pskb_copy); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 750 | |
| 751 | /** |
| 752 | * pskb_expand_head - reallocate header of &sk_buff |
| 753 | * @skb: buffer to reallocate |
| 754 | * @nhead: room to add at head |
| 755 | * @ntail: room to add at tail |
| 756 | * @gfp_mask: allocation priority |
| 757 | * |
| 758 | * Expands (or creates identical copy, if &nhead and &ntail are zero) |
| 759 | * header of skb. &sk_buff itself is not changed. &sk_buff MUST have |
| 760 | * reference count of 1. Returns zero in the case of success or error, |
| 761 | * if expansion failed. In the last case, &sk_buff is not changed. |
| 762 | * |
| 763 | * All the pointers pointing into skb header may change and must be |
| 764 | * reloaded after call to this function. |
| 765 | */ |
| 766 | |
Victor Fusco | 86a76ca | 2005-07-08 14:57:47 -0700 | [diff] [blame] | 767 | int pskb_expand_head(struct sk_buff *skb, int nhead, int ntail, |
Al Viro | dd0fc66 | 2005-10-07 07:46:04 +0100 | [diff] [blame] | 768 | gfp_t gfp_mask) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 769 | { |
| 770 | int i; |
| 771 | u8 *data; |
Eric Dumazet | 6602ceb | 2010-09-01 05:25:10 +0000 | [diff] [blame] | 772 | int size = nhead + (skb_end_pointer(skb) - skb->head) + ntail; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 773 | long off; |
Eric Dumazet | 1fd6304 | 2010-09-02 23:09:32 +0000 | [diff] [blame] | 774 | bool fastpath; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 775 | |
Herbert Xu | 4edd87a | 2008-10-01 07:09:38 -0700 | [diff] [blame] | 776 | BUG_ON(nhead < 0); |
| 777 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 778 | if (skb_shared(skb)) |
| 779 | BUG(); |
| 780 | |
| 781 | size = SKB_DATA_ALIGN(size); |
| 782 | |
Changli Gao | ca44ac3 | 2010-11-29 22:48:46 +0000 | [diff] [blame] | 783 | /* Check if we can avoid taking references on fragments if we own |
| 784 | * the last reference on skb->head. (see skb_release_data()) |
| 785 | */ |
| 786 | if (!skb->cloned) |
| 787 | fastpath = true; |
| 788 | else { |
| 789 | int delta = skb->nohdr ? (1 << SKB_DATAREF_SHIFT) + 1 : 1; |
| 790 | |
| 791 | fastpath = atomic_read(&skb_shinfo(skb)->dataref) == delta; |
| 792 | } |
| 793 | |
| 794 | if (fastpath && |
| 795 | size + sizeof(struct skb_shared_info) <= ksize(skb->head)) { |
| 796 | memmove(skb->head + size, skb_shinfo(skb), |
| 797 | offsetof(struct skb_shared_info, |
| 798 | frags[skb_shinfo(skb)->nr_frags])); |
| 799 | memmove(skb->head + nhead, skb->head, |
| 800 | skb_tail_pointer(skb) - skb->head); |
| 801 | off = nhead; |
| 802 | goto adjust_others; |
| 803 | } |
| 804 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 805 | data = kmalloc(size + sizeof(struct skb_shared_info), gfp_mask); |
| 806 | if (!data) |
| 807 | goto nodata; |
| 808 | |
| 809 | /* Copy only real data... and, alas, header. This should be |
Eric Dumazet | 6602ceb | 2010-09-01 05:25:10 +0000 | [diff] [blame] | 810 | * optimized for the cases when header is void. |
| 811 | */ |
| 812 | memcpy(data + nhead, skb->head, skb_tail_pointer(skb) - skb->head); |
| 813 | |
| 814 | memcpy((struct skb_shared_info *)(data + size), |
| 815 | skb_shinfo(skb), |
Eric Dumazet | fed6638 | 2010-07-22 19:09:08 +0000 | [diff] [blame] | 816 | offsetof(struct skb_shared_info, frags[skb_shinfo(skb)->nr_frags])); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 817 | |
Eric Dumazet | 1fd6304 | 2010-09-02 23:09:32 +0000 | [diff] [blame] | 818 | if (fastpath) { |
| 819 | kfree(skb->head); |
| 820 | } else { |
| 821 | for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) |
| 822 | get_page(skb_shinfo(skb)->frags[i].page); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 823 | |
Eric Dumazet | 1fd6304 | 2010-09-02 23:09:32 +0000 | [diff] [blame] | 824 | if (skb_has_frag_list(skb)) |
| 825 | skb_clone_fraglist(skb); |
| 826 | |
| 827 | skb_release_data(skb); |
| 828 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 829 | off = (data + nhead) - skb->head; |
| 830 | |
| 831 | skb->head = data; |
Changli Gao | ca44ac3 | 2010-11-29 22:48:46 +0000 | [diff] [blame] | 832 | adjust_others: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 833 | skb->data += off; |
Arnaldo Carvalho de Melo | 4305b54 | 2007-04-19 20:43:29 -0700 | [diff] [blame] | 834 | #ifdef NET_SKBUFF_DATA_USES_OFFSET |
| 835 | skb->end = size; |
Patrick McHardy | 56eb888 | 2007-04-09 11:45:04 -0700 | [diff] [blame] | 836 | off = nhead; |
Arnaldo Carvalho de Melo | 4305b54 | 2007-04-19 20:43:29 -0700 | [diff] [blame] | 837 | #else |
| 838 | skb->end = skb->head + size; |
Patrick McHardy | 56eb888 | 2007-04-09 11:45:04 -0700 | [diff] [blame] | 839 | #endif |
Arnaldo Carvalho de Melo | 27a884d | 2007-04-19 20:29:13 -0700 | [diff] [blame] | 840 | /* {transport,network,mac}_header and tail are relative to skb->head */ |
| 841 | skb->tail += off; |
Arnaldo Carvalho de Melo | b0e380b | 2007-04-10 21:21:55 -0700 | [diff] [blame] | 842 | skb->transport_header += off; |
| 843 | skb->network_header += off; |
Stephen Hemminger | 603a8bb | 2009-06-17 12:17:34 +0000 | [diff] [blame] | 844 | if (skb_mac_header_was_set(skb)) |
| 845 | skb->mac_header += off; |
Andrea Shepard | 00c5a98 | 2010-07-22 09:12:35 +0000 | [diff] [blame] | 846 | /* Only adjust this if it actually is csum_start rather than csum */ |
| 847 | if (skb->ip_summed == CHECKSUM_PARTIAL) |
| 848 | skb->csum_start += nhead; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 849 | skb->cloned = 0; |
Patrick McHardy | 334a813 | 2007-06-25 04:35:20 -0700 | [diff] [blame] | 850 | skb->hdr_len = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 851 | skb->nohdr = 0; |
| 852 | atomic_set(&skb_shinfo(skb)->dataref, 1); |
| 853 | return 0; |
| 854 | |
| 855 | nodata: |
| 856 | return -ENOMEM; |
| 857 | } |
David S. Miller | b4ac530fc | 2009-02-10 02:09:24 -0800 | [diff] [blame] | 858 | EXPORT_SYMBOL(pskb_expand_head); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 859 | |
| 860 | /* Make private copy of skb with writable head and some headroom */ |
| 861 | |
| 862 | struct sk_buff *skb_realloc_headroom(struct sk_buff *skb, unsigned int headroom) |
| 863 | { |
| 864 | struct sk_buff *skb2; |
| 865 | int delta = headroom - skb_headroom(skb); |
| 866 | |
| 867 | if (delta <= 0) |
| 868 | skb2 = pskb_copy(skb, GFP_ATOMIC); |
| 869 | else { |
| 870 | skb2 = skb_clone(skb, GFP_ATOMIC); |
| 871 | if (skb2 && pskb_expand_head(skb2, SKB_DATA_ALIGN(delta), 0, |
| 872 | GFP_ATOMIC)) { |
| 873 | kfree_skb(skb2); |
| 874 | skb2 = NULL; |
| 875 | } |
| 876 | } |
| 877 | return skb2; |
| 878 | } |
David S. Miller | b4ac530fc | 2009-02-10 02:09:24 -0800 | [diff] [blame] | 879 | EXPORT_SYMBOL(skb_realloc_headroom); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 880 | |
| 881 | /** |
| 882 | * skb_copy_expand - copy and expand sk_buff |
| 883 | * @skb: buffer to copy |
| 884 | * @newheadroom: new free bytes at head |
| 885 | * @newtailroom: new free bytes at tail |
| 886 | * @gfp_mask: allocation priority |
| 887 | * |
| 888 | * Make a copy of both an &sk_buff and its data and while doing so |
| 889 | * allocate additional space. |
| 890 | * |
| 891 | * This is used when the caller wishes to modify the data and needs a |
| 892 | * private copy of the data to alter as well as more space for new fields. |
| 893 | * Returns %NULL on failure or the pointer to the buffer |
| 894 | * on success. The returned buffer has a reference count of 1. |
| 895 | * |
| 896 | * You must pass %GFP_ATOMIC as the allocation priority if this function |
| 897 | * is called from an interrupt. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 898 | */ |
| 899 | struct sk_buff *skb_copy_expand(const struct sk_buff *skb, |
Victor Fusco | 86a76ca | 2005-07-08 14:57:47 -0700 | [diff] [blame] | 900 | int newheadroom, int newtailroom, |
Al Viro | dd0fc66 | 2005-10-07 07:46:04 +0100 | [diff] [blame] | 901 | gfp_t gfp_mask) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 902 | { |
| 903 | /* |
| 904 | * Allocate the copy buffer |
| 905 | */ |
| 906 | struct sk_buff *n = alloc_skb(newheadroom + skb->len + newtailroom, |
| 907 | gfp_mask); |
Patrick McHardy | efd1e8d | 2007-04-10 18:30:09 -0700 | [diff] [blame] | 908 | int oldheadroom = skb_headroom(skb); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 909 | int head_copy_len, head_copy_off; |
Herbert Xu | 5288605 | 2007-09-16 16:32:11 -0700 | [diff] [blame] | 910 | int off; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 911 | |
| 912 | if (!n) |
| 913 | return NULL; |
| 914 | |
| 915 | skb_reserve(n, newheadroom); |
| 916 | |
| 917 | /* Set the tail pointer and length */ |
| 918 | skb_put(n, skb->len); |
| 919 | |
Patrick McHardy | efd1e8d | 2007-04-10 18:30:09 -0700 | [diff] [blame] | 920 | head_copy_len = oldheadroom; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 921 | head_copy_off = 0; |
| 922 | if (newheadroom <= head_copy_len) |
| 923 | head_copy_len = newheadroom; |
| 924 | else |
| 925 | head_copy_off = newheadroom - head_copy_len; |
| 926 | |
| 927 | /* Copy the linear header and data. */ |
| 928 | if (skb_copy_bits(skb, -head_copy_len, n->head + head_copy_off, |
| 929 | skb->len + head_copy_len)) |
| 930 | BUG(); |
| 931 | |
| 932 | copy_skb_header(n, skb); |
| 933 | |
Patrick McHardy | efd1e8d | 2007-04-10 18:30:09 -0700 | [diff] [blame] | 934 | off = newheadroom - oldheadroom; |
David S. Miller | be2b6e6 | 2010-07-22 13:27:09 -0700 | [diff] [blame] | 935 | if (n->ip_summed == CHECKSUM_PARTIAL) |
| 936 | n->csum_start += off; |
Herbert Xu | 5288605 | 2007-09-16 16:32:11 -0700 | [diff] [blame] | 937 | #ifdef NET_SKBUFF_DATA_USES_OFFSET |
Patrick McHardy | efd1e8d | 2007-04-10 18:30:09 -0700 | [diff] [blame] | 938 | n->transport_header += off; |
| 939 | n->network_header += off; |
Stephen Hemminger | 603a8bb | 2009-06-17 12:17:34 +0000 | [diff] [blame] | 940 | if (skb_mac_header_was_set(skb)) |
| 941 | n->mac_header += off; |
Herbert Xu | 5288605 | 2007-09-16 16:32:11 -0700 | [diff] [blame] | 942 | #endif |
Patrick McHardy | efd1e8d | 2007-04-10 18:30:09 -0700 | [diff] [blame] | 943 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 944 | return n; |
| 945 | } |
David S. Miller | b4ac530fc | 2009-02-10 02:09:24 -0800 | [diff] [blame] | 946 | EXPORT_SYMBOL(skb_copy_expand); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 947 | |
| 948 | /** |
| 949 | * skb_pad - zero pad the tail of an skb |
| 950 | * @skb: buffer to pad |
| 951 | * @pad: space to pad |
| 952 | * |
| 953 | * Ensure that a buffer is followed by a padding area that is zero |
| 954 | * filled. Used by network drivers which may DMA or transfer data |
| 955 | * beyond the buffer end onto the wire. |
| 956 | * |
Herbert Xu | 5b057c6 | 2006-06-23 02:06:41 -0700 | [diff] [blame] | 957 | * May return error in out of memory cases. The skb is freed on error. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 958 | */ |
YOSHIFUJI Hideaki | 4ec93ed | 2007-02-09 23:24:36 +0900 | [diff] [blame] | 959 | |
Herbert Xu | 5b057c6 | 2006-06-23 02:06:41 -0700 | [diff] [blame] | 960 | int skb_pad(struct sk_buff *skb, int pad) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 961 | { |
Herbert Xu | 5b057c6 | 2006-06-23 02:06:41 -0700 | [diff] [blame] | 962 | int err; |
| 963 | int ntail; |
YOSHIFUJI Hideaki | 4ec93ed | 2007-02-09 23:24:36 +0900 | [diff] [blame] | 964 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 965 | /* If the skbuff is non linear tailroom is always zero.. */ |
Herbert Xu | 5b057c6 | 2006-06-23 02:06:41 -0700 | [diff] [blame] | 966 | if (!skb_cloned(skb) && skb_tailroom(skb) >= pad) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 967 | memset(skb->data+skb->len, 0, pad); |
Herbert Xu | 5b057c6 | 2006-06-23 02:06:41 -0700 | [diff] [blame] | 968 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 969 | } |
Herbert Xu | 5b057c6 | 2006-06-23 02:06:41 -0700 | [diff] [blame] | 970 | |
Arnaldo Carvalho de Melo | 4305b54 | 2007-04-19 20:43:29 -0700 | [diff] [blame] | 971 | ntail = skb->data_len + pad - (skb->end - skb->tail); |
Herbert Xu | 5b057c6 | 2006-06-23 02:06:41 -0700 | [diff] [blame] | 972 | if (likely(skb_cloned(skb) || ntail > 0)) { |
| 973 | err = pskb_expand_head(skb, 0, ntail, GFP_ATOMIC); |
| 974 | if (unlikely(err)) |
| 975 | goto free_skb; |
| 976 | } |
| 977 | |
| 978 | /* FIXME: The use of this function with non-linear skb's really needs |
| 979 | * to be audited. |
| 980 | */ |
| 981 | err = skb_linearize(skb); |
| 982 | if (unlikely(err)) |
| 983 | goto free_skb; |
| 984 | |
| 985 | memset(skb->data + skb->len, 0, pad); |
| 986 | return 0; |
| 987 | |
| 988 | free_skb: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 989 | kfree_skb(skb); |
Herbert Xu | 5b057c6 | 2006-06-23 02:06:41 -0700 | [diff] [blame] | 990 | return err; |
YOSHIFUJI Hideaki | 4ec93ed | 2007-02-09 23:24:36 +0900 | [diff] [blame] | 991 | } |
David S. Miller | b4ac530fc | 2009-02-10 02:09:24 -0800 | [diff] [blame] | 992 | EXPORT_SYMBOL(skb_pad); |
YOSHIFUJI Hideaki | 4ec93ed | 2007-02-09 23:24:36 +0900 | [diff] [blame] | 993 | |
Ilpo Järvinen | 0dde3e1 | 2008-03-27 17:43:41 -0700 | [diff] [blame] | 994 | /** |
| 995 | * skb_put - add data to a buffer |
| 996 | * @skb: buffer to use |
| 997 | * @len: amount of data to add |
| 998 | * |
| 999 | * This function extends the used data area of the buffer. If this would |
| 1000 | * exceed the total buffer size the kernel will panic. A pointer to the |
| 1001 | * first byte of the extra data is returned. |
| 1002 | */ |
| 1003 | unsigned char *skb_put(struct sk_buff *skb, unsigned int len) |
| 1004 | { |
| 1005 | unsigned char *tmp = skb_tail_pointer(skb); |
| 1006 | SKB_LINEAR_ASSERT(skb); |
| 1007 | skb->tail += len; |
| 1008 | skb->len += len; |
| 1009 | if (unlikely(skb->tail > skb->end)) |
| 1010 | skb_over_panic(skb, len, __builtin_return_address(0)); |
| 1011 | return tmp; |
| 1012 | } |
| 1013 | EXPORT_SYMBOL(skb_put); |
| 1014 | |
Ilpo Järvinen | 6be8ac2 | 2008-03-27 17:47:24 -0700 | [diff] [blame] | 1015 | /** |
Ilpo Järvinen | c2aa270 | 2008-03-27 17:52:40 -0700 | [diff] [blame] | 1016 | * skb_push - add data to the start of a buffer |
| 1017 | * @skb: buffer to use |
| 1018 | * @len: amount of data to add |
| 1019 | * |
| 1020 | * This function extends the used data area of the buffer at the buffer |
| 1021 | * start. If this would exceed the total buffer headroom the kernel will |
| 1022 | * panic. A pointer to the first byte of the extra data is returned. |
| 1023 | */ |
| 1024 | unsigned char *skb_push(struct sk_buff *skb, unsigned int len) |
| 1025 | { |
| 1026 | skb->data -= len; |
| 1027 | skb->len += len; |
| 1028 | if (unlikely(skb->data<skb->head)) |
| 1029 | skb_under_panic(skb, len, __builtin_return_address(0)); |
| 1030 | return skb->data; |
| 1031 | } |
| 1032 | EXPORT_SYMBOL(skb_push); |
| 1033 | |
| 1034 | /** |
Ilpo Järvinen | 6be8ac2 | 2008-03-27 17:47:24 -0700 | [diff] [blame] | 1035 | * skb_pull - remove data from the start of a buffer |
| 1036 | * @skb: buffer to use |
| 1037 | * @len: amount of data to remove |
| 1038 | * |
| 1039 | * This function removes data from the start of a buffer, returning |
| 1040 | * the memory to the headroom. A pointer to the next data in the buffer |
| 1041 | * is returned. Once the data has been pulled future pushes will overwrite |
| 1042 | * the old data. |
| 1043 | */ |
| 1044 | unsigned char *skb_pull(struct sk_buff *skb, unsigned int len) |
| 1045 | { |
David S. Miller | 47d2964 | 2010-05-02 02:21:44 -0700 | [diff] [blame] | 1046 | return skb_pull_inline(skb, len); |
Ilpo Järvinen | 6be8ac2 | 2008-03-27 17:47:24 -0700 | [diff] [blame] | 1047 | } |
| 1048 | EXPORT_SYMBOL(skb_pull); |
| 1049 | |
Ilpo Järvinen | 419ae74 | 2008-03-27 17:54:01 -0700 | [diff] [blame] | 1050 | /** |
| 1051 | * skb_trim - remove end from a buffer |
| 1052 | * @skb: buffer to alter |
| 1053 | * @len: new length |
| 1054 | * |
| 1055 | * Cut the length of a buffer down by removing data from the tail. If |
| 1056 | * the buffer is already under the length specified it is not modified. |
| 1057 | * The skb must be linear. |
| 1058 | */ |
| 1059 | void skb_trim(struct sk_buff *skb, unsigned int len) |
| 1060 | { |
| 1061 | if (skb->len > len) |
| 1062 | __skb_trim(skb, len); |
| 1063 | } |
| 1064 | EXPORT_SYMBOL(skb_trim); |
| 1065 | |
Herbert Xu | 3cc0e87 | 2006-06-09 16:13:38 -0700 | [diff] [blame] | 1066 | /* Trims skb to length len. It can change skb pointers. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1067 | */ |
| 1068 | |
Herbert Xu | 3cc0e87 | 2006-06-09 16:13:38 -0700 | [diff] [blame] | 1069 | int ___pskb_trim(struct sk_buff *skb, unsigned int len) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1070 | { |
Herbert Xu | 27b437c | 2006-07-13 19:26:39 -0700 | [diff] [blame] | 1071 | struct sk_buff **fragp; |
| 1072 | struct sk_buff *frag; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1073 | int offset = skb_headlen(skb); |
| 1074 | int nfrags = skb_shinfo(skb)->nr_frags; |
| 1075 | int i; |
Herbert Xu | 27b437c | 2006-07-13 19:26:39 -0700 | [diff] [blame] | 1076 | int err; |
| 1077 | |
| 1078 | if (skb_cloned(skb) && |
| 1079 | unlikely((err = pskb_expand_head(skb, 0, 0, GFP_ATOMIC)))) |
| 1080 | return err; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1081 | |
Herbert Xu | f4d26fb | 2006-07-30 20:20:28 -0700 | [diff] [blame] | 1082 | i = 0; |
| 1083 | if (offset >= len) |
| 1084 | goto drop_pages; |
| 1085 | |
| 1086 | for (; i < nfrags; i++) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1087 | int end = offset + skb_shinfo(skb)->frags[i].size; |
Herbert Xu | 27b437c | 2006-07-13 19:26:39 -0700 | [diff] [blame] | 1088 | |
| 1089 | if (end < len) { |
| 1090 | offset = end; |
| 1091 | continue; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1092 | } |
Herbert Xu | 27b437c | 2006-07-13 19:26:39 -0700 | [diff] [blame] | 1093 | |
Herbert Xu | f4d26fb | 2006-07-30 20:20:28 -0700 | [diff] [blame] | 1094 | skb_shinfo(skb)->frags[i++].size = len - offset; |
Herbert Xu | 27b437c | 2006-07-13 19:26:39 -0700 | [diff] [blame] | 1095 | |
Herbert Xu | f4d26fb | 2006-07-30 20:20:28 -0700 | [diff] [blame] | 1096 | drop_pages: |
Herbert Xu | 27b437c | 2006-07-13 19:26:39 -0700 | [diff] [blame] | 1097 | skb_shinfo(skb)->nr_frags = i; |
| 1098 | |
| 1099 | for (; i < nfrags; i++) |
| 1100 | put_page(skb_shinfo(skb)->frags[i].page); |
| 1101 | |
David S. Miller | 21dc330 | 2010-08-23 00:13:46 -0700 | [diff] [blame] | 1102 | if (skb_has_frag_list(skb)) |
Herbert Xu | 27b437c | 2006-07-13 19:26:39 -0700 | [diff] [blame] | 1103 | skb_drop_fraglist(skb); |
Herbert Xu | f4d26fb | 2006-07-30 20:20:28 -0700 | [diff] [blame] | 1104 | goto done; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1105 | } |
| 1106 | |
Herbert Xu | 27b437c | 2006-07-13 19:26:39 -0700 | [diff] [blame] | 1107 | for (fragp = &skb_shinfo(skb)->frag_list; (frag = *fragp); |
| 1108 | fragp = &frag->next) { |
| 1109 | int end = offset + frag->len; |
| 1110 | |
| 1111 | if (skb_shared(frag)) { |
| 1112 | struct sk_buff *nfrag; |
| 1113 | |
| 1114 | nfrag = skb_clone(frag, GFP_ATOMIC); |
| 1115 | if (unlikely(!nfrag)) |
| 1116 | return -ENOMEM; |
| 1117 | |
| 1118 | nfrag->next = frag->next; |
Herbert Xu | f4d26fb | 2006-07-30 20:20:28 -0700 | [diff] [blame] | 1119 | kfree_skb(frag); |
Herbert Xu | 27b437c | 2006-07-13 19:26:39 -0700 | [diff] [blame] | 1120 | frag = nfrag; |
| 1121 | *fragp = frag; |
| 1122 | } |
| 1123 | |
| 1124 | if (end < len) { |
| 1125 | offset = end; |
| 1126 | continue; |
| 1127 | } |
| 1128 | |
| 1129 | if (end > len && |
| 1130 | unlikely((err = pskb_trim(frag, len - offset)))) |
| 1131 | return err; |
| 1132 | |
| 1133 | if (frag->next) |
| 1134 | skb_drop_list(&frag->next); |
| 1135 | break; |
| 1136 | } |
| 1137 | |
Herbert Xu | f4d26fb | 2006-07-30 20:20:28 -0700 | [diff] [blame] | 1138 | done: |
Herbert Xu | 27b437c | 2006-07-13 19:26:39 -0700 | [diff] [blame] | 1139 | if (len > skb_headlen(skb)) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1140 | skb->data_len -= skb->len - len; |
| 1141 | skb->len = len; |
| 1142 | } else { |
Herbert Xu | 27b437c | 2006-07-13 19:26:39 -0700 | [diff] [blame] | 1143 | skb->len = len; |
| 1144 | skb->data_len = 0; |
Arnaldo Carvalho de Melo | 27a884d | 2007-04-19 20:29:13 -0700 | [diff] [blame] | 1145 | skb_set_tail_pointer(skb, len); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1146 | } |
| 1147 | |
| 1148 | return 0; |
| 1149 | } |
David S. Miller | b4ac530fc | 2009-02-10 02:09:24 -0800 | [diff] [blame] | 1150 | EXPORT_SYMBOL(___pskb_trim); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1151 | |
| 1152 | /** |
| 1153 | * __pskb_pull_tail - advance tail of skb header |
| 1154 | * @skb: buffer to reallocate |
| 1155 | * @delta: number of bytes to advance tail |
| 1156 | * |
| 1157 | * The function makes a sense only on a fragmented &sk_buff, |
| 1158 | * it expands header moving its tail forward and copying necessary |
| 1159 | * data from fragmented part. |
| 1160 | * |
| 1161 | * &sk_buff MUST have reference count of 1. |
| 1162 | * |
| 1163 | * Returns %NULL (and &sk_buff does not change) if pull failed |
| 1164 | * or value of new tail of skb in the case of success. |
| 1165 | * |
| 1166 | * All the pointers pointing into skb header may change and must be |
| 1167 | * reloaded after call to this function. |
| 1168 | */ |
| 1169 | |
| 1170 | /* Moves tail of skb head forward, copying data from fragmented part, |
| 1171 | * when it is necessary. |
| 1172 | * 1. It may fail due to malloc failure. |
| 1173 | * 2. It may change skb pointers. |
| 1174 | * |
| 1175 | * It is pretty complicated. Luckily, it is called only in exceptional cases. |
| 1176 | */ |
| 1177 | unsigned char *__pskb_pull_tail(struct sk_buff *skb, int delta) |
| 1178 | { |
| 1179 | /* If skb has not enough free space at tail, get new one |
| 1180 | * plus 128 bytes for future expansions. If we have enough |
| 1181 | * room at tail, reallocate without expansion only if skb is cloned. |
| 1182 | */ |
Arnaldo Carvalho de Melo | 4305b54 | 2007-04-19 20:43:29 -0700 | [diff] [blame] | 1183 | int i, k, eat = (skb->tail + delta) - skb->end; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1184 | |
| 1185 | if (eat > 0 || skb_cloned(skb)) { |
| 1186 | if (pskb_expand_head(skb, 0, eat > 0 ? eat + 128 : 0, |
| 1187 | GFP_ATOMIC)) |
| 1188 | return NULL; |
| 1189 | } |
| 1190 | |
Arnaldo Carvalho de Melo | 27a884d | 2007-04-19 20:29:13 -0700 | [diff] [blame] | 1191 | if (skb_copy_bits(skb, skb_headlen(skb), skb_tail_pointer(skb), delta)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1192 | BUG(); |
| 1193 | |
| 1194 | /* Optimization: no fragments, no reasons to preestimate |
| 1195 | * size of pulled pages. Superb. |
| 1196 | */ |
David S. Miller | 21dc330 | 2010-08-23 00:13:46 -0700 | [diff] [blame] | 1197 | if (!skb_has_frag_list(skb)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1198 | goto pull_pages; |
| 1199 | |
| 1200 | /* Estimate size of pulled pages. */ |
| 1201 | eat = delta; |
| 1202 | for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) { |
| 1203 | if (skb_shinfo(skb)->frags[i].size >= eat) |
| 1204 | goto pull_pages; |
| 1205 | eat -= skb_shinfo(skb)->frags[i].size; |
| 1206 | } |
| 1207 | |
| 1208 | /* If we need update frag list, we are in troubles. |
| 1209 | * Certainly, it possible to add an offset to skb data, |
| 1210 | * but taking into account that pulling is expected to |
| 1211 | * be very rare operation, it is worth to fight against |
| 1212 | * further bloating skb head and crucify ourselves here instead. |
| 1213 | * Pure masohism, indeed. 8)8) |
| 1214 | */ |
| 1215 | if (eat) { |
| 1216 | struct sk_buff *list = skb_shinfo(skb)->frag_list; |
| 1217 | struct sk_buff *clone = NULL; |
| 1218 | struct sk_buff *insp = NULL; |
| 1219 | |
| 1220 | do { |
Kris Katterjohn | 09a6266 | 2006-01-08 22:24:28 -0800 | [diff] [blame] | 1221 | BUG_ON(!list); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1222 | |
| 1223 | if (list->len <= eat) { |
| 1224 | /* Eaten as whole. */ |
| 1225 | eat -= list->len; |
| 1226 | list = list->next; |
| 1227 | insp = list; |
| 1228 | } else { |
| 1229 | /* Eaten partially. */ |
| 1230 | |
| 1231 | if (skb_shared(list)) { |
| 1232 | /* Sucks! We need to fork list. :-( */ |
| 1233 | clone = skb_clone(list, GFP_ATOMIC); |
| 1234 | if (!clone) |
| 1235 | return NULL; |
| 1236 | insp = list->next; |
| 1237 | list = clone; |
| 1238 | } else { |
| 1239 | /* This may be pulled without |
| 1240 | * problems. */ |
| 1241 | insp = list; |
| 1242 | } |
| 1243 | if (!pskb_pull(list, eat)) { |
Wei Yongjun | f3fbbe0 | 2009-02-25 00:37:32 +0000 | [diff] [blame] | 1244 | kfree_skb(clone); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1245 | return NULL; |
| 1246 | } |
| 1247 | break; |
| 1248 | } |
| 1249 | } while (eat); |
| 1250 | |
| 1251 | /* Free pulled out fragments. */ |
| 1252 | while ((list = skb_shinfo(skb)->frag_list) != insp) { |
| 1253 | skb_shinfo(skb)->frag_list = list->next; |
| 1254 | kfree_skb(list); |
| 1255 | } |
| 1256 | /* And insert new clone at head. */ |
| 1257 | if (clone) { |
| 1258 | clone->next = list; |
| 1259 | skb_shinfo(skb)->frag_list = clone; |
| 1260 | } |
| 1261 | } |
| 1262 | /* Success! Now we may commit changes to skb data. */ |
| 1263 | |
| 1264 | pull_pages: |
| 1265 | eat = delta; |
| 1266 | k = 0; |
| 1267 | for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) { |
| 1268 | if (skb_shinfo(skb)->frags[i].size <= eat) { |
| 1269 | put_page(skb_shinfo(skb)->frags[i].page); |
| 1270 | eat -= skb_shinfo(skb)->frags[i].size; |
| 1271 | } else { |
| 1272 | skb_shinfo(skb)->frags[k] = skb_shinfo(skb)->frags[i]; |
| 1273 | if (eat) { |
| 1274 | skb_shinfo(skb)->frags[k].page_offset += eat; |
| 1275 | skb_shinfo(skb)->frags[k].size -= eat; |
| 1276 | eat = 0; |
| 1277 | } |
| 1278 | k++; |
| 1279 | } |
| 1280 | } |
| 1281 | skb_shinfo(skb)->nr_frags = k; |
| 1282 | |
| 1283 | skb->tail += delta; |
| 1284 | skb->data_len -= delta; |
| 1285 | |
Arnaldo Carvalho de Melo | 27a884d | 2007-04-19 20:29:13 -0700 | [diff] [blame] | 1286 | return skb_tail_pointer(skb); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1287 | } |
David S. Miller | b4ac530fc | 2009-02-10 02:09:24 -0800 | [diff] [blame] | 1288 | EXPORT_SYMBOL(__pskb_pull_tail); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1289 | |
| 1290 | /* Copy some data bits from skb to kernel buffer. */ |
| 1291 | |
| 1292 | int skb_copy_bits(const struct sk_buff *skb, int offset, void *to, int len) |
| 1293 | { |
David S. Miller | 1a028e5 | 2007-04-27 15:21:23 -0700 | [diff] [blame] | 1294 | int start = skb_headlen(skb); |
David S. Miller | fbb398a | 2009-06-09 00:18:59 -0700 | [diff] [blame] | 1295 | struct sk_buff *frag_iter; |
| 1296 | int i, copy; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1297 | |
| 1298 | if (offset > (int)skb->len - len) |
| 1299 | goto fault; |
| 1300 | |
| 1301 | /* Copy header. */ |
David S. Miller | 1a028e5 | 2007-04-27 15:21:23 -0700 | [diff] [blame] | 1302 | if ((copy = start - offset) > 0) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1303 | if (copy > len) |
| 1304 | copy = len; |
Arnaldo Carvalho de Melo | d626f62 | 2007-03-27 18:55:52 -0300 | [diff] [blame] | 1305 | skb_copy_from_linear_data_offset(skb, offset, to, copy); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1306 | if ((len -= copy) == 0) |
| 1307 | return 0; |
| 1308 | offset += copy; |
| 1309 | to += copy; |
| 1310 | } |
| 1311 | |
| 1312 | for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) { |
David S. Miller | 1a028e5 | 2007-04-27 15:21:23 -0700 | [diff] [blame] | 1313 | int end; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1314 | |
Ilpo Järvinen | 547b792 | 2008-07-25 21:43:18 -0700 | [diff] [blame] | 1315 | WARN_ON(start > offset + len); |
David S. Miller | 1a028e5 | 2007-04-27 15:21:23 -0700 | [diff] [blame] | 1316 | |
| 1317 | end = start + skb_shinfo(skb)->frags[i].size; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1318 | if ((copy = end - offset) > 0) { |
| 1319 | u8 *vaddr; |
| 1320 | |
| 1321 | if (copy > len) |
| 1322 | copy = len; |
| 1323 | |
| 1324 | vaddr = kmap_skb_frag(&skb_shinfo(skb)->frags[i]); |
| 1325 | memcpy(to, |
David S. Miller | 1a028e5 | 2007-04-27 15:21:23 -0700 | [diff] [blame] | 1326 | vaddr + skb_shinfo(skb)->frags[i].page_offset+ |
| 1327 | offset - start, copy); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1328 | kunmap_skb_frag(vaddr); |
| 1329 | |
| 1330 | if ((len -= copy) == 0) |
| 1331 | return 0; |
| 1332 | offset += copy; |
| 1333 | to += copy; |
| 1334 | } |
David S. Miller | 1a028e5 | 2007-04-27 15:21:23 -0700 | [diff] [blame] | 1335 | start = end; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1336 | } |
| 1337 | |
David S. Miller | fbb398a | 2009-06-09 00:18:59 -0700 | [diff] [blame] | 1338 | skb_walk_frags(skb, frag_iter) { |
| 1339 | int end; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1340 | |
David S. Miller | fbb398a | 2009-06-09 00:18:59 -0700 | [diff] [blame] | 1341 | WARN_ON(start > offset + len); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1342 | |
David S. Miller | fbb398a | 2009-06-09 00:18:59 -0700 | [diff] [blame] | 1343 | end = start + frag_iter->len; |
| 1344 | if ((copy = end - offset) > 0) { |
| 1345 | if (copy > len) |
| 1346 | copy = len; |
| 1347 | if (skb_copy_bits(frag_iter, offset - start, to, copy)) |
| 1348 | goto fault; |
| 1349 | if ((len -= copy) == 0) |
| 1350 | return 0; |
| 1351 | offset += copy; |
| 1352 | to += copy; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1353 | } |
David S. Miller | fbb398a | 2009-06-09 00:18:59 -0700 | [diff] [blame] | 1354 | start = end; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1355 | } |
| 1356 | if (!len) |
| 1357 | return 0; |
| 1358 | |
| 1359 | fault: |
| 1360 | return -EFAULT; |
| 1361 | } |
David S. Miller | b4ac530fc | 2009-02-10 02:09:24 -0800 | [diff] [blame] | 1362 | EXPORT_SYMBOL(skb_copy_bits); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1363 | |
Jens Axboe | 9c55e01 | 2007-11-06 23:30:13 -0800 | [diff] [blame] | 1364 | /* |
| 1365 | * Callback from splice_to_pipe(), if we need to release some pages |
| 1366 | * at the end of the spd in case we error'ed out in filling the pipe. |
| 1367 | */ |
| 1368 | static void sock_spd_release(struct splice_pipe_desc *spd, unsigned int i) |
| 1369 | { |
Jarek Poplawski | 8b9d372 | 2009-01-19 17:03:56 -0800 | [diff] [blame] | 1370 | put_page(spd->pages[i]); |
| 1371 | } |
Jens Axboe | 9c55e01 | 2007-11-06 23:30:13 -0800 | [diff] [blame] | 1372 | |
Jarek Poplawski | 4fb6699 | 2009-02-01 00:41:42 -0800 | [diff] [blame] | 1373 | static inline struct page *linear_to_page(struct page *page, unsigned int *len, |
| 1374 | unsigned int *offset, |
Jarek Poplawski | 7a67e56 | 2009-04-30 05:41:19 -0700 | [diff] [blame] | 1375 | struct sk_buff *skb, struct sock *sk) |
Jarek Poplawski | 8b9d372 | 2009-01-19 17:03:56 -0800 | [diff] [blame] | 1376 | { |
Jarek Poplawski | 4fb6699 | 2009-02-01 00:41:42 -0800 | [diff] [blame] | 1377 | struct page *p = sk->sk_sndmsg_page; |
| 1378 | unsigned int off; |
Jarek Poplawski | 8b9d372 | 2009-01-19 17:03:56 -0800 | [diff] [blame] | 1379 | |
Jarek Poplawski | 4fb6699 | 2009-02-01 00:41:42 -0800 | [diff] [blame] | 1380 | if (!p) { |
| 1381 | new_page: |
| 1382 | p = sk->sk_sndmsg_page = alloc_pages(sk->sk_allocation, 0); |
| 1383 | if (!p) |
| 1384 | return NULL; |
| 1385 | |
| 1386 | off = sk->sk_sndmsg_off = 0; |
| 1387 | /* hold one ref to this page until it's full */ |
| 1388 | } else { |
| 1389 | unsigned int mlen; |
| 1390 | |
| 1391 | off = sk->sk_sndmsg_off; |
| 1392 | mlen = PAGE_SIZE - off; |
| 1393 | if (mlen < 64 && mlen < *len) { |
| 1394 | put_page(p); |
| 1395 | goto new_page; |
| 1396 | } |
| 1397 | |
| 1398 | *len = min_t(unsigned int, *len, mlen); |
| 1399 | } |
| 1400 | |
| 1401 | memcpy(page_address(p) + off, page_address(page) + *offset, *len); |
| 1402 | sk->sk_sndmsg_off += *len; |
| 1403 | *offset = off; |
| 1404 | get_page(p); |
Jarek Poplawski | 8b9d372 | 2009-01-19 17:03:56 -0800 | [diff] [blame] | 1405 | |
| 1406 | return p; |
Jens Axboe | 9c55e01 | 2007-11-06 23:30:13 -0800 | [diff] [blame] | 1407 | } |
| 1408 | |
| 1409 | /* |
| 1410 | * Fill page/offset/length into spd, if it can hold more pages. |
| 1411 | */ |
Jens Axboe | 35f3d14 | 2010-05-20 10:43:18 +0200 | [diff] [blame] | 1412 | static inline int spd_fill_page(struct splice_pipe_desc *spd, |
| 1413 | struct pipe_inode_info *pipe, struct page *page, |
Jarek Poplawski | 4fb6699 | 2009-02-01 00:41:42 -0800 | [diff] [blame] | 1414 | unsigned int *len, unsigned int offset, |
Jarek Poplawski | 7a67e56 | 2009-04-30 05:41:19 -0700 | [diff] [blame] | 1415 | struct sk_buff *skb, int linear, |
| 1416 | struct sock *sk) |
Jens Axboe | 9c55e01 | 2007-11-06 23:30:13 -0800 | [diff] [blame] | 1417 | { |
Jens Axboe | 35f3d14 | 2010-05-20 10:43:18 +0200 | [diff] [blame] | 1418 | if (unlikely(spd->nr_pages == pipe->buffers)) |
Jens Axboe | 9c55e01 | 2007-11-06 23:30:13 -0800 | [diff] [blame] | 1419 | return 1; |
| 1420 | |
Jarek Poplawski | 8b9d372 | 2009-01-19 17:03:56 -0800 | [diff] [blame] | 1421 | if (linear) { |
Jarek Poplawski | 7a67e56 | 2009-04-30 05:41:19 -0700 | [diff] [blame] | 1422 | page = linear_to_page(page, len, &offset, skb, sk); |
Jarek Poplawski | 8b9d372 | 2009-01-19 17:03:56 -0800 | [diff] [blame] | 1423 | if (!page) |
| 1424 | return 1; |
| 1425 | } else |
| 1426 | get_page(page); |
| 1427 | |
Jens Axboe | 9c55e01 | 2007-11-06 23:30:13 -0800 | [diff] [blame] | 1428 | spd->pages[spd->nr_pages] = page; |
Jarek Poplawski | 4fb6699 | 2009-02-01 00:41:42 -0800 | [diff] [blame] | 1429 | spd->partial[spd->nr_pages].len = *len; |
Jens Axboe | 9c55e01 | 2007-11-06 23:30:13 -0800 | [diff] [blame] | 1430 | spd->partial[spd->nr_pages].offset = offset; |
Jens Axboe | 9c55e01 | 2007-11-06 23:30:13 -0800 | [diff] [blame] | 1431 | spd->nr_pages++; |
Jarek Poplawski | 8b9d372 | 2009-01-19 17:03:56 -0800 | [diff] [blame] | 1432 | |
Jens Axboe | 9c55e01 | 2007-11-06 23:30:13 -0800 | [diff] [blame] | 1433 | return 0; |
| 1434 | } |
| 1435 | |
Octavian Purdila | 2870c43 | 2008-07-15 00:49:11 -0700 | [diff] [blame] | 1436 | static inline void __segment_seek(struct page **page, unsigned int *poff, |
| 1437 | unsigned int *plen, unsigned int off) |
Jens Axboe | 9c55e01 | 2007-11-06 23:30:13 -0800 | [diff] [blame] | 1438 | { |
Jarek Poplawski | ce3dd39 | 2009-02-12 16:51:43 -0800 | [diff] [blame] | 1439 | unsigned long n; |
| 1440 | |
Octavian Purdila | 2870c43 | 2008-07-15 00:49:11 -0700 | [diff] [blame] | 1441 | *poff += off; |
Jarek Poplawski | ce3dd39 | 2009-02-12 16:51:43 -0800 | [diff] [blame] | 1442 | n = *poff / PAGE_SIZE; |
| 1443 | if (n) |
| 1444 | *page = nth_page(*page, n); |
| 1445 | |
Octavian Purdila | 2870c43 | 2008-07-15 00:49:11 -0700 | [diff] [blame] | 1446 | *poff = *poff % PAGE_SIZE; |
| 1447 | *plen -= off; |
| 1448 | } |
Jens Axboe | 9c55e01 | 2007-11-06 23:30:13 -0800 | [diff] [blame] | 1449 | |
Octavian Purdila | 2870c43 | 2008-07-15 00:49:11 -0700 | [diff] [blame] | 1450 | static inline int __splice_segment(struct page *page, unsigned int poff, |
| 1451 | unsigned int plen, unsigned int *off, |
| 1452 | unsigned int *len, struct sk_buff *skb, |
Jarek Poplawski | 7a67e56 | 2009-04-30 05:41:19 -0700 | [diff] [blame] | 1453 | struct splice_pipe_desc *spd, int linear, |
Jens Axboe | 35f3d14 | 2010-05-20 10:43:18 +0200 | [diff] [blame] | 1454 | struct sock *sk, |
| 1455 | struct pipe_inode_info *pipe) |
Octavian Purdila | 2870c43 | 2008-07-15 00:49:11 -0700 | [diff] [blame] | 1456 | { |
| 1457 | if (!*len) |
| 1458 | return 1; |
| 1459 | |
| 1460 | /* skip this segment if already processed */ |
| 1461 | if (*off >= plen) { |
| 1462 | *off -= plen; |
| 1463 | return 0; |
Octavian Purdila | db43a28 | 2008-06-27 17:27:21 -0700 | [diff] [blame] | 1464 | } |
Jens Axboe | 9c55e01 | 2007-11-06 23:30:13 -0800 | [diff] [blame] | 1465 | |
Octavian Purdila | 2870c43 | 2008-07-15 00:49:11 -0700 | [diff] [blame] | 1466 | /* ignore any bits we already processed */ |
| 1467 | if (*off) { |
| 1468 | __segment_seek(&page, &poff, &plen, *off); |
| 1469 | *off = 0; |
| 1470 | } |
| 1471 | |
| 1472 | do { |
| 1473 | unsigned int flen = min(*len, plen); |
| 1474 | |
| 1475 | /* the linear region may spread across several pages */ |
| 1476 | flen = min_t(unsigned int, flen, PAGE_SIZE - poff); |
| 1477 | |
Jens Axboe | 35f3d14 | 2010-05-20 10:43:18 +0200 | [diff] [blame] | 1478 | if (spd_fill_page(spd, pipe, page, &flen, poff, skb, linear, sk)) |
Octavian Purdila | 2870c43 | 2008-07-15 00:49:11 -0700 | [diff] [blame] | 1479 | return 1; |
| 1480 | |
| 1481 | __segment_seek(&page, &poff, &plen, flen); |
| 1482 | *len -= flen; |
| 1483 | |
| 1484 | } while (*len && plen); |
| 1485 | |
| 1486 | return 0; |
| 1487 | } |
| 1488 | |
| 1489 | /* |
| 1490 | * Map linear and fragment data from the skb to spd. It reports failure if the |
| 1491 | * pipe is full or if we already spliced the requested length. |
| 1492 | */ |
Jens Axboe | 35f3d14 | 2010-05-20 10:43:18 +0200 | [diff] [blame] | 1493 | static int __skb_splice_bits(struct sk_buff *skb, struct pipe_inode_info *pipe, |
| 1494 | unsigned int *offset, unsigned int *len, |
| 1495 | struct splice_pipe_desc *spd, struct sock *sk) |
Octavian Purdila | 2870c43 | 2008-07-15 00:49:11 -0700 | [diff] [blame] | 1496 | { |
| 1497 | int seg; |
| 1498 | |
Jens Axboe | 9c55e01 | 2007-11-06 23:30:13 -0800 | [diff] [blame] | 1499 | /* |
Octavian Purdila | 2870c43 | 2008-07-15 00:49:11 -0700 | [diff] [blame] | 1500 | * map the linear part |
Jens Axboe | 9c55e01 | 2007-11-06 23:30:13 -0800 | [diff] [blame] | 1501 | */ |
Octavian Purdila | 2870c43 | 2008-07-15 00:49:11 -0700 | [diff] [blame] | 1502 | if (__splice_segment(virt_to_page(skb->data), |
| 1503 | (unsigned long) skb->data & (PAGE_SIZE - 1), |
| 1504 | skb_headlen(skb), |
Jens Axboe | 35f3d14 | 2010-05-20 10:43:18 +0200 | [diff] [blame] | 1505 | offset, len, skb, spd, 1, sk, pipe)) |
Octavian Purdila | 2870c43 | 2008-07-15 00:49:11 -0700 | [diff] [blame] | 1506 | return 1; |
Jens Axboe | 9c55e01 | 2007-11-06 23:30:13 -0800 | [diff] [blame] | 1507 | |
| 1508 | /* |
| 1509 | * then map the fragments |
| 1510 | */ |
Jens Axboe | 9c55e01 | 2007-11-06 23:30:13 -0800 | [diff] [blame] | 1511 | for (seg = 0; seg < skb_shinfo(skb)->nr_frags; seg++) { |
| 1512 | const skb_frag_t *f = &skb_shinfo(skb)->frags[seg]; |
| 1513 | |
Octavian Purdila | 2870c43 | 2008-07-15 00:49:11 -0700 | [diff] [blame] | 1514 | if (__splice_segment(f->page, f->page_offset, f->size, |
Jens Axboe | 35f3d14 | 2010-05-20 10:43:18 +0200 | [diff] [blame] | 1515 | offset, len, skb, spd, 0, sk, pipe)) |
Octavian Purdila | 2870c43 | 2008-07-15 00:49:11 -0700 | [diff] [blame] | 1516 | return 1; |
Jens Axboe | 9c55e01 | 2007-11-06 23:30:13 -0800 | [diff] [blame] | 1517 | } |
| 1518 | |
Octavian Purdila | 2870c43 | 2008-07-15 00:49:11 -0700 | [diff] [blame] | 1519 | return 0; |
Jens Axboe | 9c55e01 | 2007-11-06 23:30:13 -0800 | [diff] [blame] | 1520 | } |
| 1521 | |
| 1522 | /* |
| 1523 | * Map data from the skb to a pipe. Should handle both the linear part, |
| 1524 | * the fragments, and the frag list. It does NOT handle frag lists within |
| 1525 | * the frag list, if such a thing exists. We'd probably need to recurse to |
| 1526 | * handle that cleanly. |
| 1527 | */ |
Jarek Poplawski | 8b9d372 | 2009-01-19 17:03:56 -0800 | [diff] [blame] | 1528 | int skb_splice_bits(struct sk_buff *skb, unsigned int offset, |
Jens Axboe | 9c55e01 | 2007-11-06 23:30:13 -0800 | [diff] [blame] | 1529 | struct pipe_inode_info *pipe, unsigned int tlen, |
| 1530 | unsigned int flags) |
| 1531 | { |
Jens Axboe | 35f3d14 | 2010-05-20 10:43:18 +0200 | [diff] [blame] | 1532 | struct partial_page partial[PIPE_DEF_BUFFERS]; |
| 1533 | struct page *pages[PIPE_DEF_BUFFERS]; |
Jens Axboe | 9c55e01 | 2007-11-06 23:30:13 -0800 | [diff] [blame] | 1534 | struct splice_pipe_desc spd = { |
| 1535 | .pages = pages, |
| 1536 | .partial = partial, |
| 1537 | .flags = flags, |
| 1538 | .ops = &sock_pipe_buf_ops, |
| 1539 | .spd_release = sock_spd_release, |
| 1540 | }; |
David S. Miller | fbb398a | 2009-06-09 00:18:59 -0700 | [diff] [blame] | 1541 | struct sk_buff *frag_iter; |
Jarek Poplawski | 7a67e56 | 2009-04-30 05:41:19 -0700 | [diff] [blame] | 1542 | struct sock *sk = skb->sk; |
Jens Axboe | 35f3d14 | 2010-05-20 10:43:18 +0200 | [diff] [blame] | 1543 | int ret = 0; |
| 1544 | |
| 1545 | if (splice_grow_spd(pipe, &spd)) |
| 1546 | return -ENOMEM; |
Jens Axboe | 9c55e01 | 2007-11-06 23:30:13 -0800 | [diff] [blame] | 1547 | |
| 1548 | /* |
| 1549 | * __skb_splice_bits() only fails if the output has no room left, |
| 1550 | * so no point in going over the frag_list for the error case. |
| 1551 | */ |
Jens Axboe | 35f3d14 | 2010-05-20 10:43:18 +0200 | [diff] [blame] | 1552 | if (__skb_splice_bits(skb, pipe, &offset, &tlen, &spd, sk)) |
Jens Axboe | 9c55e01 | 2007-11-06 23:30:13 -0800 | [diff] [blame] | 1553 | goto done; |
| 1554 | else if (!tlen) |
| 1555 | goto done; |
| 1556 | |
| 1557 | /* |
| 1558 | * now see if we have a frag_list to map |
| 1559 | */ |
David S. Miller | fbb398a | 2009-06-09 00:18:59 -0700 | [diff] [blame] | 1560 | skb_walk_frags(skb, frag_iter) { |
| 1561 | if (!tlen) |
| 1562 | break; |
Jens Axboe | 35f3d14 | 2010-05-20 10:43:18 +0200 | [diff] [blame] | 1563 | if (__skb_splice_bits(frag_iter, pipe, &offset, &tlen, &spd, sk)) |
David S. Miller | fbb398a | 2009-06-09 00:18:59 -0700 | [diff] [blame] | 1564 | break; |
Jens Axboe | 9c55e01 | 2007-11-06 23:30:13 -0800 | [diff] [blame] | 1565 | } |
| 1566 | |
| 1567 | done: |
Jens Axboe | 9c55e01 | 2007-11-06 23:30:13 -0800 | [diff] [blame] | 1568 | if (spd.nr_pages) { |
Jens Axboe | 9c55e01 | 2007-11-06 23:30:13 -0800 | [diff] [blame] | 1569 | /* |
| 1570 | * Drop the socket lock, otherwise we have reverse |
| 1571 | * locking dependencies between sk_lock and i_mutex |
| 1572 | * here as compared to sendfile(). We enter here |
| 1573 | * with the socket lock held, and splice_to_pipe() will |
| 1574 | * grab the pipe inode lock. For sendfile() emulation, |
| 1575 | * we call into ->sendpage() with the i_mutex lock held |
| 1576 | * and networking will grab the socket lock. |
| 1577 | */ |
Octavian Purdila | 293ad60 | 2008-06-04 15:45:58 -0700 | [diff] [blame] | 1578 | release_sock(sk); |
Jens Axboe | 9c55e01 | 2007-11-06 23:30:13 -0800 | [diff] [blame] | 1579 | ret = splice_to_pipe(pipe, &spd); |
Octavian Purdila | 293ad60 | 2008-06-04 15:45:58 -0700 | [diff] [blame] | 1580 | lock_sock(sk); |
Jens Axboe | 9c55e01 | 2007-11-06 23:30:13 -0800 | [diff] [blame] | 1581 | } |
| 1582 | |
Jens Axboe | 35f3d14 | 2010-05-20 10:43:18 +0200 | [diff] [blame] | 1583 | splice_shrink_spd(pipe, &spd); |
| 1584 | return ret; |
Jens Axboe | 9c55e01 | 2007-11-06 23:30:13 -0800 | [diff] [blame] | 1585 | } |
| 1586 | |
Herbert Xu | 357b40a | 2005-04-19 22:30:14 -0700 | [diff] [blame] | 1587 | /** |
| 1588 | * skb_store_bits - store bits from kernel buffer to skb |
| 1589 | * @skb: destination buffer |
| 1590 | * @offset: offset in destination |
| 1591 | * @from: source buffer |
| 1592 | * @len: number of bytes to copy |
| 1593 | * |
| 1594 | * Copy the specified number of bytes from the source buffer to the |
| 1595 | * destination skb. This function handles all the messy bits of |
| 1596 | * traversing fragment lists and such. |
| 1597 | */ |
| 1598 | |
Stephen Hemminger | 0c6fcc8 | 2007-04-20 16:40:01 -0700 | [diff] [blame] | 1599 | int skb_store_bits(struct sk_buff *skb, int offset, const void *from, int len) |
Herbert Xu | 357b40a | 2005-04-19 22:30:14 -0700 | [diff] [blame] | 1600 | { |
David S. Miller | 1a028e5 | 2007-04-27 15:21:23 -0700 | [diff] [blame] | 1601 | int start = skb_headlen(skb); |
David S. Miller | fbb398a | 2009-06-09 00:18:59 -0700 | [diff] [blame] | 1602 | struct sk_buff *frag_iter; |
| 1603 | int i, copy; |
Herbert Xu | 357b40a | 2005-04-19 22:30:14 -0700 | [diff] [blame] | 1604 | |
| 1605 | if (offset > (int)skb->len - len) |
| 1606 | goto fault; |
| 1607 | |
David S. Miller | 1a028e5 | 2007-04-27 15:21:23 -0700 | [diff] [blame] | 1608 | if ((copy = start - offset) > 0) { |
Herbert Xu | 357b40a | 2005-04-19 22:30:14 -0700 | [diff] [blame] | 1609 | if (copy > len) |
| 1610 | copy = len; |
Arnaldo Carvalho de Melo | 27d7ff4 | 2007-03-31 11:55:19 -0300 | [diff] [blame] | 1611 | skb_copy_to_linear_data_offset(skb, offset, from, copy); |
Herbert Xu | 357b40a | 2005-04-19 22:30:14 -0700 | [diff] [blame] | 1612 | if ((len -= copy) == 0) |
| 1613 | return 0; |
| 1614 | offset += copy; |
| 1615 | from += copy; |
| 1616 | } |
| 1617 | |
| 1618 | for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) { |
| 1619 | skb_frag_t *frag = &skb_shinfo(skb)->frags[i]; |
David S. Miller | 1a028e5 | 2007-04-27 15:21:23 -0700 | [diff] [blame] | 1620 | int end; |
Herbert Xu | 357b40a | 2005-04-19 22:30:14 -0700 | [diff] [blame] | 1621 | |
Ilpo Järvinen | 547b792 | 2008-07-25 21:43:18 -0700 | [diff] [blame] | 1622 | WARN_ON(start > offset + len); |
David S. Miller | 1a028e5 | 2007-04-27 15:21:23 -0700 | [diff] [blame] | 1623 | |
| 1624 | end = start + frag->size; |
Herbert Xu | 357b40a | 2005-04-19 22:30:14 -0700 | [diff] [blame] | 1625 | if ((copy = end - offset) > 0) { |
| 1626 | u8 *vaddr; |
| 1627 | |
| 1628 | if (copy > len) |
| 1629 | copy = len; |
| 1630 | |
| 1631 | vaddr = kmap_skb_frag(frag); |
David S. Miller | 1a028e5 | 2007-04-27 15:21:23 -0700 | [diff] [blame] | 1632 | memcpy(vaddr + frag->page_offset + offset - start, |
| 1633 | from, copy); |
Herbert Xu | 357b40a | 2005-04-19 22:30:14 -0700 | [diff] [blame] | 1634 | kunmap_skb_frag(vaddr); |
| 1635 | |
| 1636 | if ((len -= copy) == 0) |
| 1637 | return 0; |
| 1638 | offset += copy; |
| 1639 | from += copy; |
| 1640 | } |
David S. Miller | 1a028e5 | 2007-04-27 15:21:23 -0700 | [diff] [blame] | 1641 | start = end; |
Herbert Xu | 357b40a | 2005-04-19 22:30:14 -0700 | [diff] [blame] | 1642 | } |
| 1643 | |
David S. Miller | fbb398a | 2009-06-09 00:18:59 -0700 | [diff] [blame] | 1644 | skb_walk_frags(skb, frag_iter) { |
| 1645 | int end; |
Herbert Xu | 357b40a | 2005-04-19 22:30:14 -0700 | [diff] [blame] | 1646 | |
David S. Miller | fbb398a | 2009-06-09 00:18:59 -0700 | [diff] [blame] | 1647 | WARN_ON(start > offset + len); |
Herbert Xu | 357b40a | 2005-04-19 22:30:14 -0700 | [diff] [blame] | 1648 | |
David S. Miller | fbb398a | 2009-06-09 00:18:59 -0700 | [diff] [blame] | 1649 | end = start + frag_iter->len; |
| 1650 | if ((copy = end - offset) > 0) { |
| 1651 | if (copy > len) |
| 1652 | copy = len; |
| 1653 | if (skb_store_bits(frag_iter, offset - start, |
| 1654 | from, copy)) |
| 1655 | goto fault; |
| 1656 | if ((len -= copy) == 0) |
| 1657 | return 0; |
| 1658 | offset += copy; |
| 1659 | from += copy; |
Herbert Xu | 357b40a | 2005-04-19 22:30:14 -0700 | [diff] [blame] | 1660 | } |
David S. Miller | fbb398a | 2009-06-09 00:18:59 -0700 | [diff] [blame] | 1661 | start = end; |
Herbert Xu | 357b40a | 2005-04-19 22:30:14 -0700 | [diff] [blame] | 1662 | } |
| 1663 | if (!len) |
| 1664 | return 0; |
| 1665 | |
| 1666 | fault: |
| 1667 | return -EFAULT; |
| 1668 | } |
Herbert Xu | 357b40a | 2005-04-19 22:30:14 -0700 | [diff] [blame] | 1669 | EXPORT_SYMBOL(skb_store_bits); |
| 1670 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1671 | /* Checksum skb data. */ |
| 1672 | |
Al Viro | 2bbbc86 | 2006-11-14 21:37:14 -0800 | [diff] [blame] | 1673 | __wsum skb_checksum(const struct sk_buff *skb, int offset, |
| 1674 | int len, __wsum csum) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1675 | { |
David S. Miller | 1a028e5 | 2007-04-27 15:21:23 -0700 | [diff] [blame] | 1676 | int start = skb_headlen(skb); |
| 1677 | int i, copy = start - offset; |
David S. Miller | fbb398a | 2009-06-09 00:18:59 -0700 | [diff] [blame] | 1678 | struct sk_buff *frag_iter; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1679 | int pos = 0; |
| 1680 | |
| 1681 | /* Checksum header. */ |
| 1682 | if (copy > 0) { |
| 1683 | if (copy > len) |
| 1684 | copy = len; |
| 1685 | csum = csum_partial(skb->data + offset, copy, csum); |
| 1686 | if ((len -= copy) == 0) |
| 1687 | return csum; |
| 1688 | offset += copy; |
| 1689 | pos = copy; |
| 1690 | } |
| 1691 | |
| 1692 | for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) { |
David S. Miller | 1a028e5 | 2007-04-27 15:21:23 -0700 | [diff] [blame] | 1693 | int end; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1694 | |
Ilpo Järvinen | 547b792 | 2008-07-25 21:43:18 -0700 | [diff] [blame] | 1695 | WARN_ON(start > offset + len); |
David S. Miller | 1a028e5 | 2007-04-27 15:21:23 -0700 | [diff] [blame] | 1696 | |
| 1697 | end = start + skb_shinfo(skb)->frags[i].size; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1698 | if ((copy = end - offset) > 0) { |
Al Viro | 44bb936 | 2006-11-14 21:36:14 -0800 | [diff] [blame] | 1699 | __wsum csum2; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1700 | u8 *vaddr; |
| 1701 | skb_frag_t *frag = &skb_shinfo(skb)->frags[i]; |
| 1702 | |
| 1703 | if (copy > len) |
| 1704 | copy = len; |
| 1705 | vaddr = kmap_skb_frag(frag); |
David S. Miller | 1a028e5 | 2007-04-27 15:21:23 -0700 | [diff] [blame] | 1706 | csum2 = csum_partial(vaddr + frag->page_offset + |
| 1707 | offset - start, copy, 0); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1708 | kunmap_skb_frag(vaddr); |
| 1709 | csum = csum_block_add(csum, csum2, pos); |
| 1710 | if (!(len -= copy)) |
| 1711 | return csum; |
| 1712 | offset += copy; |
| 1713 | pos += copy; |
| 1714 | } |
David S. Miller | 1a028e5 | 2007-04-27 15:21:23 -0700 | [diff] [blame] | 1715 | start = end; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1716 | } |
| 1717 | |
David S. Miller | fbb398a | 2009-06-09 00:18:59 -0700 | [diff] [blame] | 1718 | skb_walk_frags(skb, frag_iter) { |
| 1719 | int end; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1720 | |
David S. Miller | fbb398a | 2009-06-09 00:18:59 -0700 | [diff] [blame] | 1721 | WARN_ON(start > offset + len); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1722 | |
David S. Miller | fbb398a | 2009-06-09 00:18:59 -0700 | [diff] [blame] | 1723 | end = start + frag_iter->len; |
| 1724 | if ((copy = end - offset) > 0) { |
| 1725 | __wsum csum2; |
| 1726 | if (copy > len) |
| 1727 | copy = len; |
| 1728 | csum2 = skb_checksum(frag_iter, offset - start, |
| 1729 | copy, 0); |
| 1730 | csum = csum_block_add(csum, csum2, pos); |
| 1731 | if ((len -= copy) == 0) |
| 1732 | return csum; |
| 1733 | offset += copy; |
| 1734 | pos += copy; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1735 | } |
David S. Miller | fbb398a | 2009-06-09 00:18:59 -0700 | [diff] [blame] | 1736 | start = end; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1737 | } |
Kris Katterjohn | 09a6266 | 2006-01-08 22:24:28 -0800 | [diff] [blame] | 1738 | BUG_ON(len); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1739 | |
| 1740 | return csum; |
| 1741 | } |
David S. Miller | b4ac530fc | 2009-02-10 02:09:24 -0800 | [diff] [blame] | 1742 | EXPORT_SYMBOL(skb_checksum); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1743 | |
| 1744 | /* Both of above in one bottle. */ |
| 1745 | |
Al Viro | 81d7766 | 2006-11-14 21:37:33 -0800 | [diff] [blame] | 1746 | __wsum skb_copy_and_csum_bits(const struct sk_buff *skb, int offset, |
| 1747 | u8 *to, int len, __wsum csum) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1748 | { |
David S. Miller | 1a028e5 | 2007-04-27 15:21:23 -0700 | [diff] [blame] | 1749 | int start = skb_headlen(skb); |
| 1750 | int i, copy = start - offset; |
David S. Miller | fbb398a | 2009-06-09 00:18:59 -0700 | [diff] [blame] | 1751 | struct sk_buff *frag_iter; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1752 | int pos = 0; |
| 1753 | |
| 1754 | /* Copy header. */ |
| 1755 | if (copy > 0) { |
| 1756 | if (copy > len) |
| 1757 | copy = len; |
| 1758 | csum = csum_partial_copy_nocheck(skb->data + offset, to, |
| 1759 | copy, csum); |
| 1760 | if ((len -= copy) == 0) |
| 1761 | return csum; |
| 1762 | offset += copy; |
| 1763 | to += copy; |
| 1764 | pos = copy; |
| 1765 | } |
| 1766 | |
| 1767 | for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) { |
David S. Miller | 1a028e5 | 2007-04-27 15:21:23 -0700 | [diff] [blame] | 1768 | int end; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1769 | |
Ilpo Järvinen | 547b792 | 2008-07-25 21:43:18 -0700 | [diff] [blame] | 1770 | WARN_ON(start > offset + len); |
David S. Miller | 1a028e5 | 2007-04-27 15:21:23 -0700 | [diff] [blame] | 1771 | |
| 1772 | end = start + skb_shinfo(skb)->frags[i].size; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1773 | if ((copy = end - offset) > 0) { |
Al Viro | 5084205 | 2006-11-14 21:36:34 -0800 | [diff] [blame] | 1774 | __wsum csum2; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1775 | u8 *vaddr; |
| 1776 | skb_frag_t *frag = &skb_shinfo(skb)->frags[i]; |
| 1777 | |
| 1778 | if (copy > len) |
| 1779 | copy = len; |
| 1780 | vaddr = kmap_skb_frag(frag); |
| 1781 | csum2 = csum_partial_copy_nocheck(vaddr + |
David S. Miller | 1a028e5 | 2007-04-27 15:21:23 -0700 | [diff] [blame] | 1782 | frag->page_offset + |
| 1783 | offset - start, to, |
| 1784 | copy, 0); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1785 | kunmap_skb_frag(vaddr); |
| 1786 | csum = csum_block_add(csum, csum2, pos); |
| 1787 | if (!(len -= copy)) |
| 1788 | return csum; |
| 1789 | offset += copy; |
| 1790 | to += copy; |
| 1791 | pos += copy; |
| 1792 | } |
David S. Miller | 1a028e5 | 2007-04-27 15:21:23 -0700 | [diff] [blame] | 1793 | start = end; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1794 | } |
| 1795 | |
David S. Miller | fbb398a | 2009-06-09 00:18:59 -0700 | [diff] [blame] | 1796 | skb_walk_frags(skb, frag_iter) { |
| 1797 | __wsum csum2; |
| 1798 | int end; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1799 | |
David S. Miller | fbb398a | 2009-06-09 00:18:59 -0700 | [diff] [blame] | 1800 | WARN_ON(start > offset + len); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1801 | |
David S. Miller | fbb398a | 2009-06-09 00:18:59 -0700 | [diff] [blame] | 1802 | end = start + frag_iter->len; |
| 1803 | if ((copy = end - offset) > 0) { |
| 1804 | if (copy > len) |
| 1805 | copy = len; |
| 1806 | csum2 = skb_copy_and_csum_bits(frag_iter, |
| 1807 | offset - start, |
| 1808 | to, copy, 0); |
| 1809 | csum = csum_block_add(csum, csum2, pos); |
| 1810 | if ((len -= copy) == 0) |
| 1811 | return csum; |
| 1812 | offset += copy; |
| 1813 | to += copy; |
| 1814 | pos += copy; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1815 | } |
David S. Miller | fbb398a | 2009-06-09 00:18:59 -0700 | [diff] [blame] | 1816 | start = end; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1817 | } |
Kris Katterjohn | 09a6266 | 2006-01-08 22:24:28 -0800 | [diff] [blame] | 1818 | BUG_ON(len); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1819 | return csum; |
| 1820 | } |
David S. Miller | b4ac530fc | 2009-02-10 02:09:24 -0800 | [diff] [blame] | 1821 | EXPORT_SYMBOL(skb_copy_and_csum_bits); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1822 | |
| 1823 | void skb_copy_and_csum_dev(const struct sk_buff *skb, u8 *to) |
| 1824 | { |
Al Viro | d3bc23e | 2006-11-14 21:24:49 -0800 | [diff] [blame] | 1825 | __wsum csum; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1826 | long csstart; |
| 1827 | |
Patrick McHardy | 84fa793 | 2006-08-29 16:44:56 -0700 | [diff] [blame] | 1828 | if (skb->ip_summed == CHECKSUM_PARTIAL) |
Michał Mirosław | 55508d6 | 2010-12-14 15:24:08 +0000 | [diff] [blame] | 1829 | csstart = skb_checksum_start_offset(skb); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1830 | else |
| 1831 | csstart = skb_headlen(skb); |
| 1832 | |
Kris Katterjohn | 09a6266 | 2006-01-08 22:24:28 -0800 | [diff] [blame] | 1833 | BUG_ON(csstart > skb_headlen(skb)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1834 | |
Arnaldo Carvalho de Melo | d626f62 | 2007-03-27 18:55:52 -0300 | [diff] [blame] | 1835 | skb_copy_from_linear_data(skb, to, csstart); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1836 | |
| 1837 | csum = 0; |
| 1838 | if (csstart != skb->len) |
| 1839 | csum = skb_copy_and_csum_bits(skb, csstart, to + csstart, |
| 1840 | skb->len - csstart, 0); |
| 1841 | |
Patrick McHardy | 84fa793 | 2006-08-29 16:44:56 -0700 | [diff] [blame] | 1842 | if (skb->ip_summed == CHECKSUM_PARTIAL) { |
Al Viro | ff1dcad | 2006-11-20 18:07:29 -0800 | [diff] [blame] | 1843 | long csstuff = csstart + skb->csum_offset; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1844 | |
Al Viro | d3bc23e | 2006-11-14 21:24:49 -0800 | [diff] [blame] | 1845 | *((__sum16 *)(to + csstuff)) = csum_fold(csum); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1846 | } |
| 1847 | } |
David S. Miller | b4ac530fc | 2009-02-10 02:09:24 -0800 | [diff] [blame] | 1848 | EXPORT_SYMBOL(skb_copy_and_csum_dev); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1849 | |
| 1850 | /** |
| 1851 | * skb_dequeue - remove from the head of the queue |
| 1852 | * @list: list to dequeue from |
| 1853 | * |
| 1854 | * Remove the head of the list. The list lock is taken so the function |
| 1855 | * may be used safely with other locking list functions. The head item is |
| 1856 | * returned or %NULL if the list is empty. |
| 1857 | */ |
| 1858 | |
| 1859 | struct sk_buff *skb_dequeue(struct sk_buff_head *list) |
| 1860 | { |
| 1861 | unsigned long flags; |
| 1862 | struct sk_buff *result; |
| 1863 | |
| 1864 | spin_lock_irqsave(&list->lock, flags); |
| 1865 | result = __skb_dequeue(list); |
| 1866 | spin_unlock_irqrestore(&list->lock, flags); |
| 1867 | return result; |
| 1868 | } |
David S. Miller | b4ac530fc | 2009-02-10 02:09:24 -0800 | [diff] [blame] | 1869 | EXPORT_SYMBOL(skb_dequeue); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1870 | |
| 1871 | /** |
| 1872 | * skb_dequeue_tail - remove from the tail of the queue |
| 1873 | * @list: list to dequeue from |
| 1874 | * |
| 1875 | * Remove the tail of the list. The list lock is taken so the function |
| 1876 | * may be used safely with other locking list functions. The tail item is |
| 1877 | * returned or %NULL if the list is empty. |
| 1878 | */ |
| 1879 | struct sk_buff *skb_dequeue_tail(struct sk_buff_head *list) |
| 1880 | { |
| 1881 | unsigned long flags; |
| 1882 | struct sk_buff *result; |
| 1883 | |
| 1884 | spin_lock_irqsave(&list->lock, flags); |
| 1885 | result = __skb_dequeue_tail(list); |
| 1886 | spin_unlock_irqrestore(&list->lock, flags); |
| 1887 | return result; |
| 1888 | } |
David S. Miller | b4ac530fc | 2009-02-10 02:09:24 -0800 | [diff] [blame] | 1889 | EXPORT_SYMBOL(skb_dequeue_tail); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1890 | |
| 1891 | /** |
| 1892 | * skb_queue_purge - empty a list |
| 1893 | * @list: list to empty |
| 1894 | * |
| 1895 | * Delete all buffers on an &sk_buff list. Each buffer is removed from |
| 1896 | * the list and one reference dropped. This function takes the list |
| 1897 | * lock and is atomic with respect to other list locking functions. |
| 1898 | */ |
| 1899 | void skb_queue_purge(struct sk_buff_head *list) |
| 1900 | { |
| 1901 | struct sk_buff *skb; |
| 1902 | while ((skb = skb_dequeue(list)) != NULL) |
| 1903 | kfree_skb(skb); |
| 1904 | } |
David S. Miller | b4ac530fc | 2009-02-10 02:09:24 -0800 | [diff] [blame] | 1905 | EXPORT_SYMBOL(skb_queue_purge); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1906 | |
| 1907 | /** |
| 1908 | * skb_queue_head - queue a buffer at the list head |
| 1909 | * @list: list to use |
| 1910 | * @newsk: buffer to queue |
| 1911 | * |
| 1912 | * Queue a buffer at the start of the list. This function takes the |
| 1913 | * list lock and can be used safely with other locking &sk_buff functions |
| 1914 | * safely. |
| 1915 | * |
| 1916 | * A buffer cannot be placed on two lists at the same time. |
| 1917 | */ |
| 1918 | void skb_queue_head(struct sk_buff_head *list, struct sk_buff *newsk) |
| 1919 | { |
| 1920 | unsigned long flags; |
| 1921 | |
| 1922 | spin_lock_irqsave(&list->lock, flags); |
| 1923 | __skb_queue_head(list, newsk); |
| 1924 | spin_unlock_irqrestore(&list->lock, flags); |
| 1925 | } |
David S. Miller | b4ac530fc | 2009-02-10 02:09:24 -0800 | [diff] [blame] | 1926 | EXPORT_SYMBOL(skb_queue_head); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1927 | |
| 1928 | /** |
| 1929 | * skb_queue_tail - queue a buffer at the list tail |
| 1930 | * @list: list to use |
| 1931 | * @newsk: buffer to queue |
| 1932 | * |
| 1933 | * Queue a buffer at the tail of the list. This function takes the |
| 1934 | * list lock and can be used safely with other locking &sk_buff functions |
| 1935 | * safely. |
| 1936 | * |
| 1937 | * A buffer cannot be placed on two lists at the same time. |
| 1938 | */ |
| 1939 | void skb_queue_tail(struct sk_buff_head *list, struct sk_buff *newsk) |
| 1940 | { |
| 1941 | unsigned long flags; |
| 1942 | |
| 1943 | spin_lock_irqsave(&list->lock, flags); |
| 1944 | __skb_queue_tail(list, newsk); |
| 1945 | spin_unlock_irqrestore(&list->lock, flags); |
| 1946 | } |
David S. Miller | b4ac530fc | 2009-02-10 02:09:24 -0800 | [diff] [blame] | 1947 | EXPORT_SYMBOL(skb_queue_tail); |
David S. Miller | 8728b83 | 2005-08-09 19:25:21 -0700 | [diff] [blame] | 1948 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1949 | /** |
| 1950 | * skb_unlink - remove a buffer from a list |
| 1951 | * @skb: buffer to remove |
David S. Miller | 8728b83 | 2005-08-09 19:25:21 -0700 | [diff] [blame] | 1952 | * @list: list to use |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1953 | * |
David S. Miller | 8728b83 | 2005-08-09 19:25:21 -0700 | [diff] [blame] | 1954 | * Remove a packet from a list. The list locks are taken and this |
| 1955 | * function is atomic with respect to other list locked calls |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1956 | * |
David S. Miller | 8728b83 | 2005-08-09 19:25:21 -0700 | [diff] [blame] | 1957 | * You must know what list the SKB is on. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1958 | */ |
David S. Miller | 8728b83 | 2005-08-09 19:25:21 -0700 | [diff] [blame] | 1959 | void skb_unlink(struct sk_buff *skb, struct sk_buff_head *list) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1960 | { |
David S. Miller | 8728b83 | 2005-08-09 19:25:21 -0700 | [diff] [blame] | 1961 | unsigned long flags; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1962 | |
David S. Miller | 8728b83 | 2005-08-09 19:25:21 -0700 | [diff] [blame] | 1963 | spin_lock_irqsave(&list->lock, flags); |
| 1964 | __skb_unlink(skb, list); |
| 1965 | spin_unlock_irqrestore(&list->lock, flags); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1966 | } |
David S. Miller | b4ac530fc | 2009-02-10 02:09:24 -0800 | [diff] [blame] | 1967 | EXPORT_SYMBOL(skb_unlink); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1968 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1969 | /** |
| 1970 | * skb_append - append a buffer |
| 1971 | * @old: buffer to insert after |
| 1972 | * @newsk: buffer to insert |
David S. Miller | 8728b83 | 2005-08-09 19:25:21 -0700 | [diff] [blame] | 1973 | * @list: list to use |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1974 | * |
| 1975 | * Place a packet after a given packet in a list. The list locks are taken |
| 1976 | * and this function is atomic with respect to other list locked calls. |
| 1977 | * A buffer cannot be placed on two lists at the same time. |
| 1978 | */ |
David S. Miller | 8728b83 | 2005-08-09 19:25:21 -0700 | [diff] [blame] | 1979 | 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] | 1980 | { |
| 1981 | unsigned long flags; |
| 1982 | |
David S. Miller | 8728b83 | 2005-08-09 19:25:21 -0700 | [diff] [blame] | 1983 | spin_lock_irqsave(&list->lock, flags); |
Gerrit Renker | 7de6c03 | 2008-04-14 00:05:09 -0700 | [diff] [blame] | 1984 | __skb_queue_after(list, old, newsk); |
David S. Miller | 8728b83 | 2005-08-09 19:25:21 -0700 | [diff] [blame] | 1985 | spin_unlock_irqrestore(&list->lock, flags); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1986 | } |
David S. Miller | b4ac530fc | 2009-02-10 02:09:24 -0800 | [diff] [blame] | 1987 | EXPORT_SYMBOL(skb_append); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1988 | |
| 1989 | /** |
| 1990 | * skb_insert - insert a buffer |
| 1991 | * @old: buffer to insert before |
| 1992 | * @newsk: buffer to insert |
David S. Miller | 8728b83 | 2005-08-09 19:25:21 -0700 | [diff] [blame] | 1993 | * @list: list to use |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1994 | * |
David S. Miller | 8728b83 | 2005-08-09 19:25:21 -0700 | [diff] [blame] | 1995 | * Place a packet before a given packet in a list. The list locks are |
| 1996 | * taken and this function is atomic with respect to other list locked |
| 1997 | * calls. |
| 1998 | * |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1999 | * A buffer cannot be placed on two lists at the same time. |
| 2000 | */ |
David S. Miller | 8728b83 | 2005-08-09 19:25:21 -0700 | [diff] [blame] | 2001 | 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] | 2002 | { |
| 2003 | unsigned long flags; |
| 2004 | |
David S. Miller | 8728b83 | 2005-08-09 19:25:21 -0700 | [diff] [blame] | 2005 | spin_lock_irqsave(&list->lock, flags); |
| 2006 | __skb_insert(newsk, old->prev, old, list); |
| 2007 | spin_unlock_irqrestore(&list->lock, flags); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2008 | } |
David S. Miller | b4ac530fc | 2009-02-10 02:09:24 -0800 | [diff] [blame] | 2009 | EXPORT_SYMBOL(skb_insert); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2010 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2011 | static inline void skb_split_inside_header(struct sk_buff *skb, |
| 2012 | struct sk_buff* skb1, |
| 2013 | const u32 len, const int pos) |
| 2014 | { |
| 2015 | int i; |
| 2016 | |
Arnaldo Carvalho de Melo | d626f62 | 2007-03-27 18:55:52 -0300 | [diff] [blame] | 2017 | skb_copy_from_linear_data_offset(skb, len, skb_put(skb1, pos - len), |
| 2018 | pos - len); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2019 | /* And move data appendix as is. */ |
| 2020 | for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) |
| 2021 | skb_shinfo(skb1)->frags[i] = skb_shinfo(skb)->frags[i]; |
| 2022 | |
| 2023 | skb_shinfo(skb1)->nr_frags = skb_shinfo(skb)->nr_frags; |
| 2024 | skb_shinfo(skb)->nr_frags = 0; |
| 2025 | skb1->data_len = skb->data_len; |
| 2026 | skb1->len += skb1->data_len; |
| 2027 | skb->data_len = 0; |
| 2028 | skb->len = len; |
Arnaldo Carvalho de Melo | 27a884d | 2007-04-19 20:29:13 -0700 | [diff] [blame] | 2029 | skb_set_tail_pointer(skb, len); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2030 | } |
| 2031 | |
| 2032 | static inline void skb_split_no_header(struct sk_buff *skb, |
| 2033 | struct sk_buff* skb1, |
| 2034 | const u32 len, int pos) |
| 2035 | { |
| 2036 | int i, k = 0; |
| 2037 | const int nfrags = skb_shinfo(skb)->nr_frags; |
| 2038 | |
| 2039 | skb_shinfo(skb)->nr_frags = 0; |
| 2040 | skb1->len = skb1->data_len = skb->len - len; |
| 2041 | skb->len = len; |
| 2042 | skb->data_len = len - pos; |
| 2043 | |
| 2044 | for (i = 0; i < nfrags; i++) { |
| 2045 | int size = skb_shinfo(skb)->frags[i].size; |
| 2046 | |
| 2047 | if (pos + size > len) { |
| 2048 | skb_shinfo(skb1)->frags[k] = skb_shinfo(skb)->frags[i]; |
| 2049 | |
| 2050 | if (pos < len) { |
| 2051 | /* Split frag. |
| 2052 | * We have two variants in this case: |
| 2053 | * 1. Move all the frag to the second |
| 2054 | * part, if it is possible. F.e. |
| 2055 | * this approach is mandatory for TUX, |
| 2056 | * where splitting is expensive. |
| 2057 | * 2. Split is accurately. We make this. |
| 2058 | */ |
| 2059 | get_page(skb_shinfo(skb)->frags[i].page); |
| 2060 | skb_shinfo(skb1)->frags[0].page_offset += len - pos; |
| 2061 | skb_shinfo(skb1)->frags[0].size -= len - pos; |
| 2062 | skb_shinfo(skb)->frags[i].size = len - pos; |
| 2063 | skb_shinfo(skb)->nr_frags++; |
| 2064 | } |
| 2065 | k++; |
| 2066 | } else |
| 2067 | skb_shinfo(skb)->nr_frags++; |
| 2068 | pos += size; |
| 2069 | } |
| 2070 | skb_shinfo(skb1)->nr_frags = k; |
| 2071 | } |
| 2072 | |
| 2073 | /** |
| 2074 | * skb_split - Split fragmented skb to two parts at length len. |
| 2075 | * @skb: the buffer to split |
| 2076 | * @skb1: the buffer to receive the second part |
| 2077 | * @len: new length for skb |
| 2078 | */ |
| 2079 | void skb_split(struct sk_buff *skb, struct sk_buff *skb1, const u32 len) |
| 2080 | { |
| 2081 | int pos = skb_headlen(skb); |
| 2082 | |
| 2083 | if (len < pos) /* Split line is inside header. */ |
| 2084 | skb_split_inside_header(skb, skb1, len, pos); |
| 2085 | else /* Second chunk has no header, nothing to copy. */ |
| 2086 | skb_split_no_header(skb, skb1, len, pos); |
| 2087 | } |
David S. Miller | b4ac530fc | 2009-02-10 02:09:24 -0800 | [diff] [blame] | 2088 | EXPORT_SYMBOL(skb_split); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2089 | |
Ilpo Järvinen | 9f782db | 2008-11-25 13:57:01 -0800 | [diff] [blame] | 2090 | /* Shifting from/to a cloned skb is a no-go. |
| 2091 | * |
| 2092 | * Caller cannot keep skb_shinfo related pointers past calling here! |
| 2093 | */ |
Ilpo Järvinen | 832d11c | 2008-11-24 21:20:15 -0800 | [diff] [blame] | 2094 | static int skb_prepare_for_shift(struct sk_buff *skb) |
| 2095 | { |
Ilpo Järvinen | 0ace285 | 2008-11-24 21:30:21 -0800 | [diff] [blame] | 2096 | return skb_cloned(skb) && pskb_expand_head(skb, 0, 0, GFP_ATOMIC); |
Ilpo Järvinen | 832d11c | 2008-11-24 21:20:15 -0800 | [diff] [blame] | 2097 | } |
| 2098 | |
| 2099 | /** |
| 2100 | * skb_shift - Shifts paged data partially from skb to another |
| 2101 | * @tgt: buffer into which tail data gets added |
| 2102 | * @skb: buffer from which the paged data comes from |
| 2103 | * @shiftlen: shift up to this many bytes |
| 2104 | * |
| 2105 | * Attempts to shift up to shiftlen worth of bytes, which may be less than |
| 2106 | * the length of the skb, from tgt to skb. Returns number bytes shifted. |
| 2107 | * It's up to caller to free skb if everything was shifted. |
| 2108 | * |
| 2109 | * If @tgt runs out of frags, the whole operation is aborted. |
| 2110 | * |
| 2111 | * Skb cannot include anything else but paged data while tgt is allowed |
| 2112 | * to have non-paged data as well. |
| 2113 | * |
| 2114 | * TODO: full sized shift could be optimized but that would need |
| 2115 | * specialized skb free'er to handle frags without up-to-date nr_frags. |
| 2116 | */ |
| 2117 | int skb_shift(struct sk_buff *tgt, struct sk_buff *skb, int shiftlen) |
| 2118 | { |
| 2119 | int from, to, merge, todo; |
| 2120 | struct skb_frag_struct *fragfrom, *fragto; |
| 2121 | |
| 2122 | BUG_ON(shiftlen > skb->len); |
| 2123 | BUG_ON(skb_headlen(skb)); /* Would corrupt stream */ |
| 2124 | |
| 2125 | todo = shiftlen; |
| 2126 | from = 0; |
| 2127 | to = skb_shinfo(tgt)->nr_frags; |
| 2128 | fragfrom = &skb_shinfo(skb)->frags[from]; |
| 2129 | |
| 2130 | /* Actual merge is delayed until the point when we know we can |
| 2131 | * commit all, so that we don't have to undo partial changes |
| 2132 | */ |
| 2133 | if (!to || |
| 2134 | !skb_can_coalesce(tgt, to, fragfrom->page, fragfrom->page_offset)) { |
| 2135 | merge = -1; |
| 2136 | } else { |
| 2137 | merge = to - 1; |
| 2138 | |
| 2139 | todo -= fragfrom->size; |
| 2140 | if (todo < 0) { |
| 2141 | if (skb_prepare_for_shift(skb) || |
| 2142 | skb_prepare_for_shift(tgt)) |
| 2143 | return 0; |
| 2144 | |
Ilpo Järvinen | 9f782db | 2008-11-25 13:57:01 -0800 | [diff] [blame] | 2145 | /* All previous frag pointers might be stale! */ |
| 2146 | fragfrom = &skb_shinfo(skb)->frags[from]; |
Ilpo Järvinen | 832d11c | 2008-11-24 21:20:15 -0800 | [diff] [blame] | 2147 | fragto = &skb_shinfo(tgt)->frags[merge]; |
| 2148 | |
| 2149 | fragto->size += shiftlen; |
| 2150 | fragfrom->size -= shiftlen; |
| 2151 | fragfrom->page_offset += shiftlen; |
| 2152 | |
| 2153 | goto onlymerged; |
| 2154 | } |
| 2155 | |
| 2156 | from++; |
| 2157 | } |
| 2158 | |
| 2159 | /* Skip full, not-fitting skb to avoid expensive operations */ |
| 2160 | if ((shiftlen == skb->len) && |
| 2161 | (skb_shinfo(skb)->nr_frags - from) > (MAX_SKB_FRAGS - to)) |
| 2162 | return 0; |
| 2163 | |
| 2164 | if (skb_prepare_for_shift(skb) || skb_prepare_for_shift(tgt)) |
| 2165 | return 0; |
| 2166 | |
| 2167 | while ((todo > 0) && (from < skb_shinfo(skb)->nr_frags)) { |
| 2168 | if (to == MAX_SKB_FRAGS) |
| 2169 | return 0; |
| 2170 | |
| 2171 | fragfrom = &skb_shinfo(skb)->frags[from]; |
| 2172 | fragto = &skb_shinfo(tgt)->frags[to]; |
| 2173 | |
| 2174 | if (todo >= fragfrom->size) { |
| 2175 | *fragto = *fragfrom; |
| 2176 | todo -= fragfrom->size; |
| 2177 | from++; |
| 2178 | to++; |
| 2179 | |
| 2180 | } else { |
| 2181 | get_page(fragfrom->page); |
| 2182 | fragto->page = fragfrom->page; |
| 2183 | fragto->page_offset = fragfrom->page_offset; |
| 2184 | fragto->size = todo; |
| 2185 | |
| 2186 | fragfrom->page_offset += todo; |
| 2187 | fragfrom->size -= todo; |
| 2188 | todo = 0; |
| 2189 | |
| 2190 | to++; |
| 2191 | break; |
| 2192 | } |
| 2193 | } |
| 2194 | |
| 2195 | /* Ready to "commit" this state change to tgt */ |
| 2196 | skb_shinfo(tgt)->nr_frags = to; |
| 2197 | |
| 2198 | if (merge >= 0) { |
| 2199 | fragfrom = &skb_shinfo(skb)->frags[0]; |
| 2200 | fragto = &skb_shinfo(tgt)->frags[merge]; |
| 2201 | |
| 2202 | fragto->size += fragfrom->size; |
| 2203 | put_page(fragfrom->page); |
| 2204 | } |
| 2205 | |
| 2206 | /* Reposition in the original skb */ |
| 2207 | to = 0; |
| 2208 | while (from < skb_shinfo(skb)->nr_frags) |
| 2209 | skb_shinfo(skb)->frags[to++] = skb_shinfo(skb)->frags[from++]; |
| 2210 | skb_shinfo(skb)->nr_frags = to; |
| 2211 | |
| 2212 | BUG_ON(todo > 0 && !skb_shinfo(skb)->nr_frags); |
| 2213 | |
| 2214 | onlymerged: |
| 2215 | /* Most likely the tgt won't ever need its checksum anymore, skb on |
| 2216 | * the other hand might need it if it needs to be resent |
| 2217 | */ |
| 2218 | tgt->ip_summed = CHECKSUM_PARTIAL; |
| 2219 | skb->ip_summed = CHECKSUM_PARTIAL; |
| 2220 | |
| 2221 | /* Yak, is it really working this way? Some helper please? */ |
| 2222 | skb->len -= shiftlen; |
| 2223 | skb->data_len -= shiftlen; |
| 2224 | skb->truesize -= shiftlen; |
| 2225 | tgt->len += shiftlen; |
| 2226 | tgt->data_len += shiftlen; |
| 2227 | tgt->truesize += shiftlen; |
| 2228 | |
| 2229 | return shiftlen; |
| 2230 | } |
| 2231 | |
Thomas Graf | 677e90e | 2005-06-23 20:59:51 -0700 | [diff] [blame] | 2232 | /** |
| 2233 | * skb_prepare_seq_read - Prepare a sequential read of skb data |
| 2234 | * @skb: the buffer to read |
| 2235 | * @from: lower offset of data to be read |
| 2236 | * @to: upper offset of data to be read |
| 2237 | * @st: state variable |
| 2238 | * |
| 2239 | * Initializes the specified state variable. Must be called before |
| 2240 | * invoking skb_seq_read() for the first time. |
| 2241 | */ |
| 2242 | void skb_prepare_seq_read(struct sk_buff *skb, unsigned int from, |
| 2243 | unsigned int to, struct skb_seq_state *st) |
| 2244 | { |
| 2245 | st->lower_offset = from; |
| 2246 | st->upper_offset = to; |
| 2247 | st->root_skb = st->cur_skb = skb; |
| 2248 | st->frag_idx = st->stepped_offset = 0; |
| 2249 | st->frag_data = NULL; |
| 2250 | } |
David S. Miller | b4ac530fc | 2009-02-10 02:09:24 -0800 | [diff] [blame] | 2251 | EXPORT_SYMBOL(skb_prepare_seq_read); |
Thomas Graf | 677e90e | 2005-06-23 20:59:51 -0700 | [diff] [blame] | 2252 | |
| 2253 | /** |
| 2254 | * skb_seq_read - Sequentially read skb data |
| 2255 | * @consumed: number of bytes consumed by the caller so far |
| 2256 | * @data: destination pointer for data to be returned |
| 2257 | * @st: state variable |
| 2258 | * |
| 2259 | * Reads a block of skb data at &consumed relative to the |
| 2260 | * lower offset specified to skb_prepare_seq_read(). Assigns |
| 2261 | * the head of the data block to &data and returns the length |
| 2262 | * of the block or 0 if the end of the skb data or the upper |
| 2263 | * offset has been reached. |
| 2264 | * |
| 2265 | * The caller is not required to consume all of the data |
| 2266 | * returned, i.e. &consumed is typically set to the number |
| 2267 | * of bytes already consumed and the next call to |
| 2268 | * skb_seq_read() will return the remaining part of the block. |
| 2269 | * |
Randy Dunlap | bc2cda1 | 2008-02-13 15:03:25 -0800 | [diff] [blame] | 2270 | * Note 1: The size of each block of data returned can be arbitary, |
Thomas Graf | 677e90e | 2005-06-23 20:59:51 -0700 | [diff] [blame] | 2271 | * this limitation is the cost for zerocopy seqeuental |
| 2272 | * reads of potentially non linear data. |
| 2273 | * |
Randy Dunlap | bc2cda1 | 2008-02-13 15:03:25 -0800 | [diff] [blame] | 2274 | * Note 2: Fragment lists within fragments are not implemented |
Thomas Graf | 677e90e | 2005-06-23 20:59:51 -0700 | [diff] [blame] | 2275 | * at the moment, state->root_skb could be replaced with |
| 2276 | * a stack for this purpose. |
| 2277 | */ |
| 2278 | unsigned int skb_seq_read(unsigned int consumed, const u8 **data, |
| 2279 | struct skb_seq_state *st) |
| 2280 | { |
| 2281 | unsigned int block_limit, abs_offset = consumed + st->lower_offset; |
| 2282 | skb_frag_t *frag; |
| 2283 | |
| 2284 | if (unlikely(abs_offset >= st->upper_offset)) |
| 2285 | return 0; |
| 2286 | |
| 2287 | next_skb: |
Herbert Xu | 95e3b24 | 2009-01-29 16:07:52 -0800 | [diff] [blame] | 2288 | block_limit = skb_headlen(st->cur_skb) + st->stepped_offset; |
Thomas Graf | 677e90e | 2005-06-23 20:59:51 -0700 | [diff] [blame] | 2289 | |
Thomas Chenault | 995b337 | 2009-05-18 21:43:27 -0700 | [diff] [blame] | 2290 | if (abs_offset < block_limit && !st->frag_data) { |
Herbert Xu | 95e3b24 | 2009-01-29 16:07:52 -0800 | [diff] [blame] | 2291 | *data = st->cur_skb->data + (abs_offset - st->stepped_offset); |
Thomas Graf | 677e90e | 2005-06-23 20:59:51 -0700 | [diff] [blame] | 2292 | return block_limit - abs_offset; |
| 2293 | } |
| 2294 | |
| 2295 | if (st->frag_idx == 0 && !st->frag_data) |
| 2296 | st->stepped_offset += skb_headlen(st->cur_skb); |
| 2297 | |
| 2298 | while (st->frag_idx < skb_shinfo(st->cur_skb)->nr_frags) { |
| 2299 | frag = &skb_shinfo(st->cur_skb)->frags[st->frag_idx]; |
| 2300 | block_limit = frag->size + st->stepped_offset; |
| 2301 | |
| 2302 | if (abs_offset < block_limit) { |
| 2303 | if (!st->frag_data) |
| 2304 | st->frag_data = kmap_skb_frag(frag); |
| 2305 | |
| 2306 | *data = (u8 *) st->frag_data + frag->page_offset + |
| 2307 | (abs_offset - st->stepped_offset); |
| 2308 | |
| 2309 | return block_limit - abs_offset; |
| 2310 | } |
| 2311 | |
| 2312 | if (st->frag_data) { |
| 2313 | kunmap_skb_frag(st->frag_data); |
| 2314 | st->frag_data = NULL; |
| 2315 | } |
| 2316 | |
| 2317 | st->frag_idx++; |
| 2318 | st->stepped_offset += frag->size; |
| 2319 | } |
| 2320 | |
Olaf Kirch | 5b5a60d | 2007-06-23 23:11:52 -0700 | [diff] [blame] | 2321 | if (st->frag_data) { |
| 2322 | kunmap_skb_frag(st->frag_data); |
| 2323 | st->frag_data = NULL; |
| 2324 | } |
| 2325 | |
David S. Miller | 21dc330 | 2010-08-23 00:13:46 -0700 | [diff] [blame] | 2326 | if (st->root_skb == st->cur_skb && skb_has_frag_list(st->root_skb)) { |
Shyam Iyer | 71b3346 | 2009-01-29 16:12:42 -0800 | [diff] [blame] | 2327 | st->cur_skb = skb_shinfo(st->root_skb)->frag_list; |
Thomas Graf | 677e90e | 2005-06-23 20:59:51 -0700 | [diff] [blame] | 2328 | st->frag_idx = 0; |
| 2329 | goto next_skb; |
Shyam Iyer | 71b3346 | 2009-01-29 16:12:42 -0800 | [diff] [blame] | 2330 | } else if (st->cur_skb->next) { |
| 2331 | st->cur_skb = st->cur_skb->next; |
Herbert Xu | 95e3b24 | 2009-01-29 16:07:52 -0800 | [diff] [blame] | 2332 | st->frag_idx = 0; |
Thomas Graf | 677e90e | 2005-06-23 20:59:51 -0700 | [diff] [blame] | 2333 | goto next_skb; |
| 2334 | } |
| 2335 | |
| 2336 | return 0; |
| 2337 | } |
David S. Miller | b4ac530fc | 2009-02-10 02:09:24 -0800 | [diff] [blame] | 2338 | EXPORT_SYMBOL(skb_seq_read); |
Thomas Graf | 677e90e | 2005-06-23 20:59:51 -0700 | [diff] [blame] | 2339 | |
| 2340 | /** |
| 2341 | * skb_abort_seq_read - Abort a sequential read of skb data |
| 2342 | * @st: state variable |
| 2343 | * |
| 2344 | * Must be called if skb_seq_read() was not called until it |
| 2345 | * returned 0. |
| 2346 | */ |
| 2347 | void skb_abort_seq_read(struct skb_seq_state *st) |
| 2348 | { |
| 2349 | if (st->frag_data) |
| 2350 | kunmap_skb_frag(st->frag_data); |
| 2351 | } |
David S. Miller | b4ac530fc | 2009-02-10 02:09:24 -0800 | [diff] [blame] | 2352 | EXPORT_SYMBOL(skb_abort_seq_read); |
Thomas Graf | 677e90e | 2005-06-23 20:59:51 -0700 | [diff] [blame] | 2353 | |
Thomas Graf | 3fc7e8a | 2005-06-23 21:00:17 -0700 | [diff] [blame] | 2354 | #define TS_SKB_CB(state) ((struct skb_seq_state *) &((state)->cb)) |
| 2355 | |
| 2356 | static unsigned int skb_ts_get_next_block(unsigned int offset, const u8 **text, |
| 2357 | struct ts_config *conf, |
| 2358 | struct ts_state *state) |
| 2359 | { |
| 2360 | return skb_seq_read(offset, text, TS_SKB_CB(state)); |
| 2361 | } |
| 2362 | |
| 2363 | static void skb_ts_finish(struct ts_config *conf, struct ts_state *state) |
| 2364 | { |
| 2365 | skb_abort_seq_read(TS_SKB_CB(state)); |
| 2366 | } |
| 2367 | |
| 2368 | /** |
| 2369 | * skb_find_text - Find a text pattern in skb data |
| 2370 | * @skb: the buffer to look in |
| 2371 | * @from: search offset |
| 2372 | * @to: search limit |
| 2373 | * @config: textsearch configuration |
| 2374 | * @state: uninitialized textsearch state variable |
| 2375 | * |
| 2376 | * Finds a pattern in the skb data according to the specified |
| 2377 | * textsearch configuration. Use textsearch_next() to retrieve |
| 2378 | * subsequent occurrences of the pattern. Returns the offset |
| 2379 | * to the first occurrence or UINT_MAX if no match was found. |
| 2380 | */ |
| 2381 | unsigned int skb_find_text(struct sk_buff *skb, unsigned int from, |
| 2382 | unsigned int to, struct ts_config *config, |
| 2383 | struct ts_state *state) |
| 2384 | { |
Phil Oester | f72b948 | 2006-06-26 00:00:57 -0700 | [diff] [blame] | 2385 | unsigned int ret; |
| 2386 | |
Thomas Graf | 3fc7e8a | 2005-06-23 21:00:17 -0700 | [diff] [blame] | 2387 | config->get_next_block = skb_ts_get_next_block; |
| 2388 | config->finish = skb_ts_finish; |
| 2389 | |
| 2390 | skb_prepare_seq_read(skb, from, to, TS_SKB_CB(state)); |
| 2391 | |
Phil Oester | f72b948 | 2006-06-26 00:00:57 -0700 | [diff] [blame] | 2392 | ret = textsearch_find(config, state); |
| 2393 | return (ret <= to - from ? ret : UINT_MAX); |
Thomas Graf | 3fc7e8a | 2005-06-23 21:00:17 -0700 | [diff] [blame] | 2394 | } |
David S. Miller | b4ac530fc | 2009-02-10 02:09:24 -0800 | [diff] [blame] | 2395 | EXPORT_SYMBOL(skb_find_text); |
Thomas Graf | 3fc7e8a | 2005-06-23 21:00:17 -0700 | [diff] [blame] | 2396 | |
Ananda Raju | e89e9cf | 2005-10-18 15:46:41 -0700 | [diff] [blame] | 2397 | /** |
| 2398 | * skb_append_datato_frags: - append the user data to a skb |
| 2399 | * @sk: sock structure |
| 2400 | * @skb: skb structure to be appened with user data. |
| 2401 | * @getfrag: call back function to be used for getting the user data |
| 2402 | * @from: pointer to user message iov |
| 2403 | * @length: length of the iov message |
| 2404 | * |
| 2405 | * Description: This procedure append the user data in the fragment part |
| 2406 | * of the skb if any page alloc fails user this procedure returns -ENOMEM |
| 2407 | */ |
| 2408 | int skb_append_datato_frags(struct sock *sk, struct sk_buff *skb, |
Martin Waitz | dab9630 | 2005-12-05 13:40:12 -0800 | [diff] [blame] | 2409 | int (*getfrag)(void *from, char *to, int offset, |
Ananda Raju | e89e9cf | 2005-10-18 15:46:41 -0700 | [diff] [blame] | 2410 | int len, int odd, struct sk_buff *skb), |
| 2411 | void *from, int length) |
| 2412 | { |
| 2413 | int frg_cnt = 0; |
| 2414 | skb_frag_t *frag = NULL; |
| 2415 | struct page *page = NULL; |
| 2416 | int copy, left; |
| 2417 | int offset = 0; |
| 2418 | int ret; |
| 2419 | |
| 2420 | do { |
| 2421 | /* Return error if we don't have space for new frag */ |
| 2422 | frg_cnt = skb_shinfo(skb)->nr_frags; |
| 2423 | if (frg_cnt >= MAX_SKB_FRAGS) |
| 2424 | return -EFAULT; |
| 2425 | |
| 2426 | /* allocate a new page for next frag */ |
| 2427 | page = alloc_pages(sk->sk_allocation, 0); |
| 2428 | |
| 2429 | /* If alloc_page fails just return failure and caller will |
| 2430 | * free previous allocated pages by doing kfree_skb() |
| 2431 | */ |
| 2432 | if (page == NULL) |
| 2433 | return -ENOMEM; |
| 2434 | |
| 2435 | /* initialize the next frag */ |
| 2436 | sk->sk_sndmsg_page = page; |
| 2437 | sk->sk_sndmsg_off = 0; |
| 2438 | skb_fill_page_desc(skb, frg_cnt, page, 0, 0); |
| 2439 | skb->truesize += PAGE_SIZE; |
| 2440 | atomic_add(PAGE_SIZE, &sk->sk_wmem_alloc); |
| 2441 | |
| 2442 | /* get the new initialized frag */ |
| 2443 | frg_cnt = skb_shinfo(skb)->nr_frags; |
| 2444 | frag = &skb_shinfo(skb)->frags[frg_cnt - 1]; |
| 2445 | |
| 2446 | /* copy the user data to page */ |
| 2447 | left = PAGE_SIZE - frag->page_offset; |
| 2448 | copy = (length > left)? left : length; |
| 2449 | |
| 2450 | ret = getfrag(from, (page_address(frag->page) + |
| 2451 | frag->page_offset + frag->size), |
| 2452 | offset, copy, 0, skb); |
| 2453 | if (ret < 0) |
| 2454 | return -EFAULT; |
| 2455 | |
| 2456 | /* copy was successful so update the size parameters */ |
| 2457 | sk->sk_sndmsg_off += copy; |
| 2458 | frag->size += copy; |
| 2459 | skb->len += copy; |
| 2460 | skb->data_len += copy; |
| 2461 | offset += copy; |
| 2462 | length -= copy; |
| 2463 | |
| 2464 | } while (length > 0); |
| 2465 | |
| 2466 | return 0; |
| 2467 | } |
David S. Miller | b4ac530fc | 2009-02-10 02:09:24 -0800 | [diff] [blame] | 2468 | EXPORT_SYMBOL(skb_append_datato_frags); |
Ananda Raju | e89e9cf | 2005-10-18 15:46:41 -0700 | [diff] [blame] | 2469 | |
Herbert Xu | cbb042f | 2006-03-20 22:43:56 -0800 | [diff] [blame] | 2470 | /** |
| 2471 | * skb_pull_rcsum - pull skb and update receive checksum |
| 2472 | * @skb: buffer to update |
Herbert Xu | cbb042f | 2006-03-20 22:43:56 -0800 | [diff] [blame] | 2473 | * @len: length of data pulled |
| 2474 | * |
| 2475 | * This function performs an skb_pull on the packet and updates |
Urs Thuermann | fee54fa | 2008-02-12 22:03:25 -0800 | [diff] [blame] | 2476 | * the CHECKSUM_COMPLETE checksum. It should be used on |
Patrick McHardy | 84fa793 | 2006-08-29 16:44:56 -0700 | [diff] [blame] | 2477 | * receive path processing instead of skb_pull unless you know |
| 2478 | * that the checksum difference is zero (e.g., a valid IP header) |
| 2479 | * or you are setting ip_summed to CHECKSUM_NONE. |
Herbert Xu | cbb042f | 2006-03-20 22:43:56 -0800 | [diff] [blame] | 2480 | */ |
| 2481 | unsigned char *skb_pull_rcsum(struct sk_buff *skb, unsigned int len) |
| 2482 | { |
| 2483 | BUG_ON(len > skb->len); |
| 2484 | skb->len -= len; |
| 2485 | BUG_ON(skb->len < skb->data_len); |
| 2486 | skb_postpull_rcsum(skb, skb->data, len); |
| 2487 | return skb->data += len; |
| 2488 | } |
Arnaldo Carvalho de Melo | f94691a | 2006-03-20 22:47:55 -0800 | [diff] [blame] | 2489 | EXPORT_SYMBOL_GPL(skb_pull_rcsum); |
| 2490 | |
Herbert Xu | f4c50d9 | 2006-06-22 03:02:40 -0700 | [diff] [blame] | 2491 | /** |
| 2492 | * skb_segment - Perform protocol segmentation on skb. |
| 2493 | * @skb: buffer to segment |
Herbert Xu | 576a30e | 2006-06-27 13:22:38 -0700 | [diff] [blame] | 2494 | * @features: features for the output path (see dev->features) |
Herbert Xu | f4c50d9 | 2006-06-22 03:02:40 -0700 | [diff] [blame] | 2495 | * |
| 2496 | * This function performs segmentation on the given skb. It returns |
Ben Hutchings | 4c821d7 | 2008-04-13 21:52:48 -0700 | [diff] [blame] | 2497 | * a pointer to the first in a list of new skbs for the segments. |
| 2498 | * In case of error it returns ERR_PTR(err). |
Herbert Xu | f4c50d9 | 2006-06-22 03:02:40 -0700 | [diff] [blame] | 2499 | */ |
Herbert Xu | 576a30e | 2006-06-27 13:22:38 -0700 | [diff] [blame] | 2500 | struct sk_buff *skb_segment(struct sk_buff *skb, int features) |
Herbert Xu | f4c50d9 | 2006-06-22 03:02:40 -0700 | [diff] [blame] | 2501 | { |
| 2502 | struct sk_buff *segs = NULL; |
| 2503 | struct sk_buff *tail = NULL; |
Herbert Xu | 89319d38 | 2008-12-15 23:26:06 -0800 | [diff] [blame] | 2504 | struct sk_buff *fskb = skb_shinfo(skb)->frag_list; |
Herbert Xu | f4c50d9 | 2006-06-22 03:02:40 -0700 | [diff] [blame] | 2505 | unsigned int mss = skb_shinfo(skb)->gso_size; |
Arnaldo Carvalho de Melo | 98e399f | 2007-03-19 15:33:04 -0700 | [diff] [blame] | 2506 | unsigned int doffset = skb->data - skb_mac_header(skb); |
Herbert Xu | f4c50d9 | 2006-06-22 03:02:40 -0700 | [diff] [blame] | 2507 | unsigned int offset = doffset; |
| 2508 | unsigned int headroom; |
| 2509 | unsigned int len; |
Herbert Xu | 576a30e | 2006-06-27 13:22:38 -0700 | [diff] [blame] | 2510 | int sg = features & NETIF_F_SG; |
Herbert Xu | f4c50d9 | 2006-06-22 03:02:40 -0700 | [diff] [blame] | 2511 | int nfrags = skb_shinfo(skb)->nr_frags; |
| 2512 | int err = -ENOMEM; |
| 2513 | int i = 0; |
| 2514 | int pos; |
| 2515 | |
| 2516 | __skb_push(skb, doffset); |
| 2517 | headroom = skb_headroom(skb); |
| 2518 | pos = skb_headlen(skb); |
| 2519 | |
| 2520 | do { |
| 2521 | struct sk_buff *nskb; |
| 2522 | skb_frag_t *frag; |
Herbert Xu | c8884ed | 2006-10-29 15:59:41 -0800 | [diff] [blame] | 2523 | int hsize; |
Herbert Xu | f4c50d9 | 2006-06-22 03:02:40 -0700 | [diff] [blame] | 2524 | int size; |
| 2525 | |
| 2526 | len = skb->len - offset; |
| 2527 | if (len > mss) |
| 2528 | len = mss; |
| 2529 | |
| 2530 | hsize = skb_headlen(skb) - offset; |
| 2531 | if (hsize < 0) |
| 2532 | hsize = 0; |
Herbert Xu | c8884ed | 2006-10-29 15:59:41 -0800 | [diff] [blame] | 2533 | if (hsize > len || !sg) |
| 2534 | hsize = len; |
Herbert Xu | f4c50d9 | 2006-06-22 03:02:40 -0700 | [diff] [blame] | 2535 | |
Herbert Xu | 89319d38 | 2008-12-15 23:26:06 -0800 | [diff] [blame] | 2536 | if (!hsize && i >= nfrags) { |
| 2537 | BUG_ON(fskb->len != len); |
| 2538 | |
| 2539 | pos += len; |
| 2540 | nskb = skb_clone(fskb, GFP_ATOMIC); |
| 2541 | fskb = fskb->next; |
| 2542 | |
| 2543 | if (unlikely(!nskb)) |
| 2544 | goto err; |
| 2545 | |
| 2546 | hsize = skb_end_pointer(nskb) - nskb->head; |
| 2547 | if (skb_cow_head(nskb, doffset + headroom)) { |
| 2548 | kfree_skb(nskb); |
| 2549 | goto err; |
| 2550 | } |
| 2551 | |
| 2552 | nskb->truesize += skb_end_pointer(nskb) - nskb->head - |
| 2553 | hsize; |
| 2554 | skb_release_head_state(nskb); |
| 2555 | __skb_push(nskb, doffset); |
| 2556 | } else { |
| 2557 | nskb = alloc_skb(hsize + doffset + headroom, |
| 2558 | GFP_ATOMIC); |
| 2559 | |
| 2560 | if (unlikely(!nskb)) |
| 2561 | goto err; |
| 2562 | |
| 2563 | skb_reserve(nskb, headroom); |
| 2564 | __skb_put(nskb, doffset); |
| 2565 | } |
Herbert Xu | f4c50d9 | 2006-06-22 03:02:40 -0700 | [diff] [blame] | 2566 | |
| 2567 | if (segs) |
| 2568 | tail->next = nskb; |
| 2569 | else |
| 2570 | segs = nskb; |
| 2571 | tail = nskb; |
| 2572 | |
Herbert Xu | 6f85a12 | 2008-08-15 14:55:02 -0700 | [diff] [blame] | 2573 | __copy_skb_header(nskb, skb); |
Herbert Xu | f4c50d9 | 2006-06-22 03:02:40 -0700 | [diff] [blame] | 2574 | nskb->mac_len = skb->mac_len; |
| 2575 | |
Eric Dumazet | 3d3be43 | 2010-09-01 00:50:51 +0000 | [diff] [blame] | 2576 | /* nskb and skb might have different headroom */ |
| 2577 | if (nskb->ip_summed == CHECKSUM_PARTIAL) |
| 2578 | nskb->csum_start += skb_headroom(nskb) - headroom; |
| 2579 | |
Arnaldo Carvalho de Melo | 459a98e | 2007-03-19 15:30:44 -0700 | [diff] [blame] | 2580 | skb_reset_mac_header(nskb); |
Arnaldo Carvalho de Melo | ddc7b8e | 2007-03-15 21:42:27 -0300 | [diff] [blame] | 2581 | skb_set_network_header(nskb, skb->mac_len); |
Arnaldo Carvalho de Melo | b0e380b | 2007-04-10 21:21:55 -0700 | [diff] [blame] | 2582 | nskb->transport_header = (nskb->network_header + |
| 2583 | skb_network_header_len(skb)); |
Herbert Xu | 89319d38 | 2008-12-15 23:26:06 -0800 | [diff] [blame] | 2584 | skb_copy_from_linear_data(skb, nskb->data, doffset); |
| 2585 | |
Herbert Xu | 2f18185 | 2009-03-28 23:39:18 -0700 | [diff] [blame] | 2586 | if (fskb != skb_shinfo(skb)->frag_list) |
Herbert Xu | 89319d38 | 2008-12-15 23:26:06 -0800 | [diff] [blame] | 2587 | continue; |
| 2588 | |
Herbert Xu | f4c50d9 | 2006-06-22 03:02:40 -0700 | [diff] [blame] | 2589 | if (!sg) { |
Herbert Xu | 6f85a12 | 2008-08-15 14:55:02 -0700 | [diff] [blame] | 2590 | nskb->ip_summed = CHECKSUM_NONE; |
Herbert Xu | f4c50d9 | 2006-06-22 03:02:40 -0700 | [diff] [blame] | 2591 | nskb->csum = skb_copy_and_csum_bits(skb, offset, |
| 2592 | skb_put(nskb, len), |
| 2593 | len, 0); |
| 2594 | continue; |
| 2595 | } |
| 2596 | |
| 2597 | frag = skb_shinfo(nskb)->frags; |
Herbert Xu | f4c50d9 | 2006-06-22 03:02:40 -0700 | [diff] [blame] | 2598 | |
Arnaldo Carvalho de Melo | d626f62 | 2007-03-27 18:55:52 -0300 | [diff] [blame] | 2599 | skb_copy_from_linear_data_offset(skb, offset, |
| 2600 | skb_put(nskb, hsize), hsize); |
Herbert Xu | f4c50d9 | 2006-06-22 03:02:40 -0700 | [diff] [blame] | 2601 | |
Herbert Xu | 89319d38 | 2008-12-15 23:26:06 -0800 | [diff] [blame] | 2602 | while (pos < offset + len && i < nfrags) { |
Herbert Xu | f4c50d9 | 2006-06-22 03:02:40 -0700 | [diff] [blame] | 2603 | *frag = skb_shinfo(skb)->frags[i]; |
| 2604 | get_page(frag->page); |
| 2605 | size = frag->size; |
| 2606 | |
| 2607 | if (pos < offset) { |
| 2608 | frag->page_offset += offset - pos; |
| 2609 | frag->size -= offset - pos; |
| 2610 | } |
| 2611 | |
Herbert Xu | 89319d38 | 2008-12-15 23:26:06 -0800 | [diff] [blame] | 2612 | skb_shinfo(nskb)->nr_frags++; |
Herbert Xu | f4c50d9 | 2006-06-22 03:02:40 -0700 | [diff] [blame] | 2613 | |
| 2614 | if (pos + size <= offset + len) { |
| 2615 | i++; |
| 2616 | pos += size; |
| 2617 | } else { |
| 2618 | frag->size -= pos + size - (offset + len); |
Herbert Xu | 89319d38 | 2008-12-15 23:26:06 -0800 | [diff] [blame] | 2619 | goto skip_fraglist; |
Herbert Xu | f4c50d9 | 2006-06-22 03:02:40 -0700 | [diff] [blame] | 2620 | } |
| 2621 | |
| 2622 | frag++; |
| 2623 | } |
| 2624 | |
Herbert Xu | 89319d38 | 2008-12-15 23:26:06 -0800 | [diff] [blame] | 2625 | if (pos < offset + len) { |
| 2626 | struct sk_buff *fskb2 = fskb; |
| 2627 | |
| 2628 | BUG_ON(pos + fskb->len != offset + len); |
| 2629 | |
| 2630 | pos += fskb->len; |
| 2631 | fskb = fskb->next; |
| 2632 | |
| 2633 | if (fskb2->next) { |
| 2634 | fskb2 = skb_clone(fskb2, GFP_ATOMIC); |
| 2635 | if (!fskb2) |
| 2636 | goto err; |
| 2637 | } else |
| 2638 | skb_get(fskb2); |
| 2639 | |
David S. Miller | fbb398a | 2009-06-09 00:18:59 -0700 | [diff] [blame] | 2640 | SKB_FRAG_ASSERT(nskb); |
Herbert Xu | 89319d38 | 2008-12-15 23:26:06 -0800 | [diff] [blame] | 2641 | skb_shinfo(nskb)->frag_list = fskb2; |
| 2642 | } |
| 2643 | |
| 2644 | skip_fraglist: |
Herbert Xu | f4c50d9 | 2006-06-22 03:02:40 -0700 | [diff] [blame] | 2645 | nskb->data_len = len - hsize; |
| 2646 | nskb->len += nskb->data_len; |
| 2647 | nskb->truesize += nskb->data_len; |
| 2648 | } while ((offset += len) < skb->len); |
| 2649 | |
| 2650 | return segs; |
| 2651 | |
| 2652 | err: |
| 2653 | while ((skb = segs)) { |
| 2654 | segs = skb->next; |
Patrick McHardy | b08d584 | 2007-02-27 09:57:37 -0800 | [diff] [blame] | 2655 | kfree_skb(skb); |
Herbert Xu | f4c50d9 | 2006-06-22 03:02:40 -0700 | [diff] [blame] | 2656 | } |
| 2657 | return ERR_PTR(err); |
| 2658 | } |
Herbert Xu | f4c50d9 | 2006-06-22 03:02:40 -0700 | [diff] [blame] | 2659 | EXPORT_SYMBOL_GPL(skb_segment); |
| 2660 | |
Herbert Xu | 71d93b3 | 2008-12-15 23:42:33 -0800 | [diff] [blame] | 2661 | int skb_gro_receive(struct sk_buff **head, struct sk_buff *skb) |
| 2662 | { |
| 2663 | struct sk_buff *p = *head; |
| 2664 | struct sk_buff *nskb; |
Herbert Xu | 9aaa156 | 2009-05-26 18:50:33 +0000 | [diff] [blame] | 2665 | struct skb_shared_info *skbinfo = skb_shinfo(skb); |
| 2666 | struct skb_shared_info *pinfo = skb_shinfo(p); |
Herbert Xu | 71d93b3 | 2008-12-15 23:42:33 -0800 | [diff] [blame] | 2667 | unsigned int headroom; |
Herbert Xu | 8691173 | 2009-01-29 14:19:50 +0000 | [diff] [blame] | 2668 | unsigned int len = skb_gro_len(skb); |
Herbert Xu | 67147ba | 2009-05-26 18:50:22 +0000 | [diff] [blame] | 2669 | unsigned int offset = skb_gro_offset(skb); |
| 2670 | unsigned int headlen = skb_headlen(skb); |
Herbert Xu | 71d93b3 | 2008-12-15 23:42:33 -0800 | [diff] [blame] | 2671 | |
Herbert Xu | 8691173 | 2009-01-29 14:19:50 +0000 | [diff] [blame] | 2672 | if (p->len + len >= 65536) |
Herbert Xu | 71d93b3 | 2008-12-15 23:42:33 -0800 | [diff] [blame] | 2673 | return -E2BIG; |
| 2674 | |
Herbert Xu | 9aaa156 | 2009-05-26 18:50:33 +0000 | [diff] [blame] | 2675 | if (pinfo->frag_list) |
Herbert Xu | 71d93b3 | 2008-12-15 23:42:33 -0800 | [diff] [blame] | 2676 | goto merge; |
Herbert Xu | 67147ba | 2009-05-26 18:50:22 +0000 | [diff] [blame] | 2677 | else if (headlen <= offset) { |
Herbert Xu | 42da699 | 2009-05-26 18:50:19 +0000 | [diff] [blame] | 2678 | skb_frag_t *frag; |
Herbert Xu | 66e92fc | 2009-05-26 18:50:32 +0000 | [diff] [blame] | 2679 | skb_frag_t *frag2; |
Herbert Xu | 9aaa156 | 2009-05-26 18:50:33 +0000 | [diff] [blame] | 2680 | int i = skbinfo->nr_frags; |
| 2681 | int nr_frags = pinfo->nr_frags + i; |
Herbert Xu | 42da699 | 2009-05-26 18:50:19 +0000 | [diff] [blame] | 2682 | |
Herbert Xu | 66e92fc | 2009-05-26 18:50:32 +0000 | [diff] [blame] | 2683 | offset -= headlen; |
| 2684 | |
| 2685 | if (nr_frags > MAX_SKB_FRAGS) |
Herbert Xu | 81705ad | 2009-01-29 14:19:51 +0000 | [diff] [blame] | 2686 | return -E2BIG; |
| 2687 | |
Herbert Xu | 9aaa156 | 2009-05-26 18:50:33 +0000 | [diff] [blame] | 2688 | pinfo->nr_frags = nr_frags; |
| 2689 | skbinfo->nr_frags = 0; |
Herbert Xu | f557206 | 2009-01-14 20:40:03 -0800 | [diff] [blame] | 2690 | |
Herbert Xu | 9aaa156 | 2009-05-26 18:50:33 +0000 | [diff] [blame] | 2691 | frag = pinfo->frags + nr_frags; |
| 2692 | frag2 = skbinfo->frags + i; |
Herbert Xu | 66e92fc | 2009-05-26 18:50:32 +0000 | [diff] [blame] | 2693 | do { |
| 2694 | *--frag = *--frag2; |
| 2695 | } while (--i); |
| 2696 | |
| 2697 | frag->page_offset += offset; |
| 2698 | frag->size -= offset; |
| 2699 | |
Herbert Xu | f557206 | 2009-01-14 20:40:03 -0800 | [diff] [blame] | 2700 | skb->truesize -= skb->data_len; |
| 2701 | skb->len -= skb->data_len; |
| 2702 | skb->data_len = 0; |
| 2703 | |
Herbert Xu | 5d38a07 | 2009-01-04 16:13:40 -0800 | [diff] [blame] | 2704 | NAPI_GRO_CB(skb)->free = 1; |
| 2705 | goto done; |
Herbert Xu | 69c0cab | 2009-11-17 05:18:18 -0800 | [diff] [blame] | 2706 | } else if (skb_gro_len(p) != pinfo->gso_size) |
| 2707 | return -E2BIG; |
Herbert Xu | 71d93b3 | 2008-12-15 23:42:33 -0800 | [diff] [blame] | 2708 | |
| 2709 | headroom = skb_headroom(p); |
Eric Dumazet | 3d3be43 | 2010-09-01 00:50:51 +0000 | [diff] [blame] | 2710 | nskb = alloc_skb(headroom + skb_gro_offset(p), GFP_ATOMIC); |
Herbert Xu | 71d93b3 | 2008-12-15 23:42:33 -0800 | [diff] [blame] | 2711 | if (unlikely(!nskb)) |
| 2712 | return -ENOMEM; |
| 2713 | |
| 2714 | __copy_skb_header(nskb, p); |
| 2715 | nskb->mac_len = p->mac_len; |
| 2716 | |
| 2717 | skb_reserve(nskb, headroom); |
Herbert Xu | 8691173 | 2009-01-29 14:19:50 +0000 | [diff] [blame] | 2718 | __skb_put(nskb, skb_gro_offset(p)); |
Herbert Xu | 71d93b3 | 2008-12-15 23:42:33 -0800 | [diff] [blame] | 2719 | |
Herbert Xu | 8691173 | 2009-01-29 14:19:50 +0000 | [diff] [blame] | 2720 | skb_set_mac_header(nskb, skb_mac_header(p) - p->data); |
Herbert Xu | 71d93b3 | 2008-12-15 23:42:33 -0800 | [diff] [blame] | 2721 | skb_set_network_header(nskb, skb_network_offset(p)); |
| 2722 | skb_set_transport_header(nskb, skb_transport_offset(p)); |
| 2723 | |
Herbert Xu | 8691173 | 2009-01-29 14:19:50 +0000 | [diff] [blame] | 2724 | __skb_pull(p, skb_gro_offset(p)); |
| 2725 | memcpy(skb_mac_header(nskb), skb_mac_header(p), |
| 2726 | p->data - skb_mac_header(p)); |
Herbert Xu | 71d93b3 | 2008-12-15 23:42:33 -0800 | [diff] [blame] | 2727 | |
| 2728 | *NAPI_GRO_CB(nskb) = *NAPI_GRO_CB(p); |
| 2729 | skb_shinfo(nskb)->frag_list = p; |
Herbert Xu | 9aaa156 | 2009-05-26 18:50:33 +0000 | [diff] [blame] | 2730 | skb_shinfo(nskb)->gso_size = pinfo->gso_size; |
Herbert Xu | 622e0ca | 2010-05-20 23:07:56 -0700 | [diff] [blame] | 2731 | pinfo->gso_size = 0; |
Herbert Xu | 71d93b3 | 2008-12-15 23:42:33 -0800 | [diff] [blame] | 2732 | skb_header_release(p); |
| 2733 | nskb->prev = p; |
| 2734 | |
| 2735 | nskb->data_len += p->len; |
| 2736 | nskb->truesize += p->len; |
| 2737 | nskb->len += p->len; |
| 2738 | |
| 2739 | *head = nskb; |
| 2740 | nskb->next = p->next; |
| 2741 | p->next = NULL; |
| 2742 | |
| 2743 | p = nskb; |
| 2744 | |
| 2745 | merge: |
Herbert Xu | 67147ba | 2009-05-26 18:50:22 +0000 | [diff] [blame] | 2746 | if (offset > headlen) { |
Herbert Xu | 9aaa156 | 2009-05-26 18:50:33 +0000 | [diff] [blame] | 2747 | skbinfo->frags[0].page_offset += offset - headlen; |
| 2748 | skbinfo->frags[0].size -= offset - headlen; |
Herbert Xu | 67147ba | 2009-05-26 18:50:22 +0000 | [diff] [blame] | 2749 | offset = headlen; |
Herbert Xu | 5603502 | 2009-02-05 21:26:52 -0800 | [diff] [blame] | 2750 | } |
| 2751 | |
Herbert Xu | 67147ba | 2009-05-26 18:50:22 +0000 | [diff] [blame] | 2752 | __skb_pull(skb, offset); |
Herbert Xu | 5603502 | 2009-02-05 21:26:52 -0800 | [diff] [blame] | 2753 | |
Herbert Xu | 71d93b3 | 2008-12-15 23:42:33 -0800 | [diff] [blame] | 2754 | p->prev->next = skb; |
| 2755 | p->prev = skb; |
| 2756 | skb_header_release(skb); |
| 2757 | |
Herbert Xu | 5d38a07 | 2009-01-04 16:13:40 -0800 | [diff] [blame] | 2758 | done: |
| 2759 | NAPI_GRO_CB(p)->count++; |
Herbert Xu | 37fe473 | 2009-01-17 19:48:13 +0000 | [diff] [blame] | 2760 | p->data_len += len; |
| 2761 | p->truesize += len; |
| 2762 | p->len += len; |
Herbert Xu | 71d93b3 | 2008-12-15 23:42:33 -0800 | [diff] [blame] | 2763 | |
| 2764 | NAPI_GRO_CB(skb)->same_flow = 1; |
| 2765 | return 0; |
| 2766 | } |
| 2767 | EXPORT_SYMBOL_GPL(skb_gro_receive); |
| 2768 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2769 | void __init skb_init(void) |
| 2770 | { |
| 2771 | skbuff_head_cache = kmem_cache_create("skbuff_head_cache", |
| 2772 | sizeof(struct sk_buff), |
| 2773 | 0, |
Alexey Dobriyan | e5d679f33 | 2006-08-26 19:25:52 -0700 | [diff] [blame] | 2774 | SLAB_HWCACHE_ALIGN|SLAB_PANIC, |
Paul Mundt | 20c2df8 | 2007-07-20 10:11:58 +0900 | [diff] [blame] | 2775 | NULL); |
David S. Miller | d179cd1 | 2005-08-17 14:57:30 -0700 | [diff] [blame] | 2776 | skbuff_fclone_cache = kmem_cache_create("skbuff_fclone_cache", |
| 2777 | (2*sizeof(struct sk_buff)) + |
| 2778 | sizeof(atomic_t), |
| 2779 | 0, |
Alexey Dobriyan | e5d679f33 | 2006-08-26 19:25:52 -0700 | [diff] [blame] | 2780 | SLAB_HWCACHE_ALIGN|SLAB_PANIC, |
Paul Mundt | 20c2df8 | 2007-07-20 10:11:58 +0900 | [diff] [blame] | 2781 | NULL); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2782 | } |
| 2783 | |
David Howells | 716ea3a | 2007-04-02 20:19:53 -0700 | [diff] [blame] | 2784 | /** |
| 2785 | * skb_to_sgvec - Fill a scatter-gather list from a socket buffer |
| 2786 | * @skb: Socket buffer containing the buffers to be mapped |
| 2787 | * @sg: The scatter-gather list to map into |
| 2788 | * @offset: The offset into the buffer's contents to start mapping |
| 2789 | * @len: Length of buffer space to be mapped |
| 2790 | * |
| 2791 | * Fill the specified scatter-gather list with mappings/pointers into a |
| 2792 | * region of the buffer space attached to a socket buffer. |
| 2793 | */ |
David S. Miller | 51c739d | 2007-10-30 21:29:29 -0700 | [diff] [blame] | 2794 | static int |
| 2795 | __skb_to_sgvec(struct sk_buff *skb, struct scatterlist *sg, int offset, int len) |
David Howells | 716ea3a | 2007-04-02 20:19:53 -0700 | [diff] [blame] | 2796 | { |
David S. Miller | 1a028e5 | 2007-04-27 15:21:23 -0700 | [diff] [blame] | 2797 | int start = skb_headlen(skb); |
| 2798 | int i, copy = start - offset; |
David S. Miller | fbb398a | 2009-06-09 00:18:59 -0700 | [diff] [blame] | 2799 | struct sk_buff *frag_iter; |
David Howells | 716ea3a | 2007-04-02 20:19:53 -0700 | [diff] [blame] | 2800 | int elt = 0; |
| 2801 | |
| 2802 | if (copy > 0) { |
| 2803 | if (copy > len) |
| 2804 | copy = len; |
Jens Axboe | 642f149 | 2007-10-24 11:20:47 +0200 | [diff] [blame] | 2805 | sg_set_buf(sg, skb->data + offset, copy); |
David Howells | 716ea3a | 2007-04-02 20:19:53 -0700 | [diff] [blame] | 2806 | elt++; |
| 2807 | if ((len -= copy) == 0) |
| 2808 | return elt; |
| 2809 | offset += copy; |
| 2810 | } |
| 2811 | |
| 2812 | for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) { |
David S. Miller | 1a028e5 | 2007-04-27 15:21:23 -0700 | [diff] [blame] | 2813 | int end; |
David Howells | 716ea3a | 2007-04-02 20:19:53 -0700 | [diff] [blame] | 2814 | |
Ilpo Järvinen | 547b792 | 2008-07-25 21:43:18 -0700 | [diff] [blame] | 2815 | WARN_ON(start > offset + len); |
David S. Miller | 1a028e5 | 2007-04-27 15:21:23 -0700 | [diff] [blame] | 2816 | |
| 2817 | end = start + skb_shinfo(skb)->frags[i].size; |
David Howells | 716ea3a | 2007-04-02 20:19:53 -0700 | [diff] [blame] | 2818 | if ((copy = end - offset) > 0) { |
| 2819 | skb_frag_t *frag = &skb_shinfo(skb)->frags[i]; |
| 2820 | |
| 2821 | if (copy > len) |
| 2822 | copy = len; |
Jens Axboe | 642f149 | 2007-10-24 11:20:47 +0200 | [diff] [blame] | 2823 | sg_set_page(&sg[elt], frag->page, copy, |
| 2824 | frag->page_offset+offset-start); |
David Howells | 716ea3a | 2007-04-02 20:19:53 -0700 | [diff] [blame] | 2825 | elt++; |
| 2826 | if (!(len -= copy)) |
| 2827 | return elt; |
| 2828 | offset += copy; |
| 2829 | } |
David S. Miller | 1a028e5 | 2007-04-27 15:21:23 -0700 | [diff] [blame] | 2830 | start = end; |
David Howells | 716ea3a | 2007-04-02 20:19:53 -0700 | [diff] [blame] | 2831 | } |
| 2832 | |
David S. Miller | fbb398a | 2009-06-09 00:18:59 -0700 | [diff] [blame] | 2833 | skb_walk_frags(skb, frag_iter) { |
| 2834 | int end; |
David Howells | 716ea3a | 2007-04-02 20:19:53 -0700 | [diff] [blame] | 2835 | |
David S. Miller | fbb398a | 2009-06-09 00:18:59 -0700 | [diff] [blame] | 2836 | WARN_ON(start > offset + len); |
David Howells | 716ea3a | 2007-04-02 20:19:53 -0700 | [diff] [blame] | 2837 | |
David S. Miller | fbb398a | 2009-06-09 00:18:59 -0700 | [diff] [blame] | 2838 | end = start + frag_iter->len; |
| 2839 | if ((copy = end - offset) > 0) { |
| 2840 | if (copy > len) |
| 2841 | copy = len; |
| 2842 | elt += __skb_to_sgvec(frag_iter, sg+elt, offset - start, |
| 2843 | copy); |
| 2844 | if ((len -= copy) == 0) |
| 2845 | return elt; |
| 2846 | offset += copy; |
David Howells | 716ea3a | 2007-04-02 20:19:53 -0700 | [diff] [blame] | 2847 | } |
David S. Miller | fbb398a | 2009-06-09 00:18:59 -0700 | [diff] [blame] | 2848 | start = end; |
David Howells | 716ea3a | 2007-04-02 20:19:53 -0700 | [diff] [blame] | 2849 | } |
| 2850 | BUG_ON(len); |
| 2851 | return elt; |
| 2852 | } |
| 2853 | |
David S. Miller | 51c739d | 2007-10-30 21:29:29 -0700 | [diff] [blame] | 2854 | int skb_to_sgvec(struct sk_buff *skb, struct scatterlist *sg, int offset, int len) |
| 2855 | { |
| 2856 | int nsg = __skb_to_sgvec(skb, sg, offset, len); |
| 2857 | |
Jens Axboe | c46f233 | 2007-10-31 12:06:37 +0100 | [diff] [blame] | 2858 | sg_mark_end(&sg[nsg - 1]); |
David S. Miller | 51c739d | 2007-10-30 21:29:29 -0700 | [diff] [blame] | 2859 | |
| 2860 | return nsg; |
| 2861 | } |
David S. Miller | b4ac530fc | 2009-02-10 02:09:24 -0800 | [diff] [blame] | 2862 | EXPORT_SYMBOL_GPL(skb_to_sgvec); |
David S. Miller | 51c739d | 2007-10-30 21:29:29 -0700 | [diff] [blame] | 2863 | |
David Howells | 716ea3a | 2007-04-02 20:19:53 -0700 | [diff] [blame] | 2864 | /** |
| 2865 | * skb_cow_data - Check that a socket buffer's data buffers are writable |
| 2866 | * @skb: The socket buffer to check. |
| 2867 | * @tailbits: Amount of trailing space to be added |
| 2868 | * @trailer: Returned pointer to the skb where the @tailbits space begins |
| 2869 | * |
| 2870 | * Make sure that the data buffers attached to a socket buffer are |
| 2871 | * writable. If they are not, private copies are made of the data buffers |
| 2872 | * and the socket buffer is set to use these instead. |
| 2873 | * |
| 2874 | * If @tailbits is given, make sure that there is space to write @tailbits |
| 2875 | * bytes of data beyond current end of socket buffer. @trailer will be |
| 2876 | * set to point to the skb in which this space begins. |
| 2877 | * |
| 2878 | * The number of scatterlist elements required to completely map the |
| 2879 | * COW'd and extended socket buffer will be returned. |
| 2880 | */ |
| 2881 | int skb_cow_data(struct sk_buff *skb, int tailbits, struct sk_buff **trailer) |
| 2882 | { |
| 2883 | int copyflag; |
| 2884 | int elt; |
| 2885 | struct sk_buff *skb1, **skb_p; |
| 2886 | |
| 2887 | /* If skb is cloned or its head is paged, reallocate |
| 2888 | * head pulling out all the pages (pages are considered not writable |
| 2889 | * at the moment even if they are anonymous). |
| 2890 | */ |
| 2891 | if ((skb_cloned(skb) || skb_shinfo(skb)->nr_frags) && |
| 2892 | __pskb_pull_tail(skb, skb_pagelen(skb)-skb_headlen(skb)) == NULL) |
| 2893 | return -ENOMEM; |
| 2894 | |
| 2895 | /* Easy case. Most of packets will go this way. */ |
David S. Miller | 21dc330 | 2010-08-23 00:13:46 -0700 | [diff] [blame] | 2896 | if (!skb_has_frag_list(skb)) { |
David Howells | 716ea3a | 2007-04-02 20:19:53 -0700 | [diff] [blame] | 2897 | /* A little of trouble, not enough of space for trailer. |
| 2898 | * This should not happen, when stack is tuned to generate |
| 2899 | * good frames. OK, on miss we reallocate and reserve even more |
| 2900 | * space, 128 bytes is fair. */ |
| 2901 | |
| 2902 | if (skb_tailroom(skb) < tailbits && |
| 2903 | pskb_expand_head(skb, 0, tailbits-skb_tailroom(skb)+128, GFP_ATOMIC)) |
| 2904 | return -ENOMEM; |
| 2905 | |
| 2906 | /* Voila! */ |
| 2907 | *trailer = skb; |
| 2908 | return 1; |
| 2909 | } |
| 2910 | |
| 2911 | /* Misery. We are in troubles, going to mincer fragments... */ |
| 2912 | |
| 2913 | elt = 1; |
| 2914 | skb_p = &skb_shinfo(skb)->frag_list; |
| 2915 | copyflag = 0; |
| 2916 | |
| 2917 | while ((skb1 = *skb_p) != NULL) { |
| 2918 | int ntail = 0; |
| 2919 | |
| 2920 | /* The fragment is partially pulled by someone, |
| 2921 | * this can happen on input. Copy it and everything |
| 2922 | * after it. */ |
| 2923 | |
| 2924 | if (skb_shared(skb1)) |
| 2925 | copyflag = 1; |
| 2926 | |
| 2927 | /* If the skb is the last, worry about trailer. */ |
| 2928 | |
| 2929 | if (skb1->next == NULL && tailbits) { |
| 2930 | if (skb_shinfo(skb1)->nr_frags || |
David S. Miller | 21dc330 | 2010-08-23 00:13:46 -0700 | [diff] [blame] | 2931 | skb_has_frag_list(skb1) || |
David Howells | 716ea3a | 2007-04-02 20:19:53 -0700 | [diff] [blame] | 2932 | skb_tailroom(skb1) < tailbits) |
| 2933 | ntail = tailbits + 128; |
| 2934 | } |
| 2935 | |
| 2936 | if (copyflag || |
| 2937 | skb_cloned(skb1) || |
| 2938 | ntail || |
| 2939 | skb_shinfo(skb1)->nr_frags || |
David S. Miller | 21dc330 | 2010-08-23 00:13:46 -0700 | [diff] [blame] | 2940 | skb_has_frag_list(skb1)) { |
David Howells | 716ea3a | 2007-04-02 20:19:53 -0700 | [diff] [blame] | 2941 | struct sk_buff *skb2; |
| 2942 | |
| 2943 | /* Fuck, we are miserable poor guys... */ |
| 2944 | if (ntail == 0) |
| 2945 | skb2 = skb_copy(skb1, GFP_ATOMIC); |
| 2946 | else |
| 2947 | skb2 = skb_copy_expand(skb1, |
| 2948 | skb_headroom(skb1), |
| 2949 | ntail, |
| 2950 | GFP_ATOMIC); |
| 2951 | if (unlikely(skb2 == NULL)) |
| 2952 | return -ENOMEM; |
| 2953 | |
| 2954 | if (skb1->sk) |
| 2955 | skb_set_owner_w(skb2, skb1->sk); |
| 2956 | |
| 2957 | /* Looking around. Are we still alive? |
| 2958 | * OK, link new skb, drop old one */ |
| 2959 | |
| 2960 | skb2->next = skb1->next; |
| 2961 | *skb_p = skb2; |
| 2962 | kfree_skb(skb1); |
| 2963 | skb1 = skb2; |
| 2964 | } |
| 2965 | elt++; |
| 2966 | *trailer = skb1; |
| 2967 | skb_p = &skb1->next; |
| 2968 | } |
| 2969 | |
| 2970 | return elt; |
| 2971 | } |
David S. Miller | b4ac530fc | 2009-02-10 02:09:24 -0800 | [diff] [blame] | 2972 | EXPORT_SYMBOL_GPL(skb_cow_data); |
David Howells | 716ea3a | 2007-04-02 20:19:53 -0700 | [diff] [blame] | 2973 | |
Eric Dumazet | b1faf56 | 2010-05-31 23:44:05 -0700 | [diff] [blame] | 2974 | static void sock_rmem_free(struct sk_buff *skb) |
| 2975 | { |
| 2976 | struct sock *sk = skb->sk; |
| 2977 | |
| 2978 | atomic_sub(skb->truesize, &sk->sk_rmem_alloc); |
| 2979 | } |
| 2980 | |
| 2981 | /* |
| 2982 | * Note: We dont mem charge error packets (no sk_forward_alloc changes) |
| 2983 | */ |
| 2984 | int sock_queue_err_skb(struct sock *sk, struct sk_buff *skb) |
| 2985 | { |
| 2986 | if (atomic_read(&sk->sk_rmem_alloc) + skb->truesize >= |
| 2987 | (unsigned)sk->sk_rcvbuf) |
| 2988 | return -ENOMEM; |
| 2989 | |
| 2990 | skb_orphan(skb); |
| 2991 | skb->sk = sk; |
| 2992 | skb->destructor = sock_rmem_free; |
| 2993 | atomic_add(skb->truesize, &sk->sk_rmem_alloc); |
| 2994 | |
| 2995 | skb_queue_tail(&sk->sk_error_queue, skb); |
| 2996 | if (!sock_flag(sk, SOCK_DEAD)) |
| 2997 | sk->sk_data_ready(sk, skb->len); |
| 2998 | return 0; |
| 2999 | } |
| 3000 | EXPORT_SYMBOL(sock_queue_err_skb); |
| 3001 | |
Patrick Ohly | ac45f60 | 2009-02-12 05:03:37 +0000 | [diff] [blame] | 3002 | void skb_tstamp_tx(struct sk_buff *orig_skb, |
| 3003 | struct skb_shared_hwtstamps *hwtstamps) |
| 3004 | { |
| 3005 | struct sock *sk = orig_skb->sk; |
| 3006 | struct sock_exterr_skb *serr; |
| 3007 | struct sk_buff *skb; |
| 3008 | int err; |
| 3009 | |
| 3010 | if (!sk) |
| 3011 | return; |
| 3012 | |
| 3013 | skb = skb_clone(orig_skb, GFP_ATOMIC); |
| 3014 | if (!skb) |
| 3015 | return; |
| 3016 | |
| 3017 | if (hwtstamps) { |
| 3018 | *skb_hwtstamps(skb) = |
| 3019 | *hwtstamps; |
| 3020 | } else { |
| 3021 | /* |
| 3022 | * no hardware time stamps available, |
Oliver Hartkopp | 2244d07 | 2010-08-17 08:59:14 +0000 | [diff] [blame] | 3023 | * so keep the shared tx_flags and only |
Patrick Ohly | ac45f60 | 2009-02-12 05:03:37 +0000 | [diff] [blame] | 3024 | * store software time stamp |
| 3025 | */ |
| 3026 | skb->tstamp = ktime_get_real(); |
| 3027 | } |
| 3028 | |
| 3029 | serr = SKB_EXT_ERR(skb); |
| 3030 | memset(serr, 0, sizeof(*serr)); |
| 3031 | serr->ee.ee_errno = ENOMSG; |
| 3032 | serr->ee.ee_origin = SO_EE_ORIGIN_TIMESTAMPING; |
Eric Dumazet | 2903037 | 2010-05-29 00:20:48 -0700 | [diff] [blame] | 3033 | |
Patrick Ohly | ac45f60 | 2009-02-12 05:03:37 +0000 | [diff] [blame] | 3034 | err = sock_queue_err_skb(sk, skb); |
Eric Dumazet | 2903037 | 2010-05-29 00:20:48 -0700 | [diff] [blame] | 3035 | |
Patrick Ohly | ac45f60 | 2009-02-12 05:03:37 +0000 | [diff] [blame] | 3036 | if (err) |
| 3037 | kfree_skb(skb); |
| 3038 | } |
| 3039 | EXPORT_SYMBOL_GPL(skb_tstamp_tx); |
| 3040 | |
| 3041 | |
Rusty Russell | f35d9d8 | 2008-02-04 23:49:54 -0500 | [diff] [blame] | 3042 | /** |
| 3043 | * skb_partial_csum_set - set up and verify partial csum values for packet |
| 3044 | * @skb: the skb to set |
| 3045 | * @start: the number of bytes after skb->data to start checksumming. |
| 3046 | * @off: the offset from start to place the checksum. |
| 3047 | * |
| 3048 | * For untrusted partially-checksummed packets, we need to make sure the values |
| 3049 | * for skb->csum_start and skb->csum_offset are valid so we don't oops. |
| 3050 | * |
| 3051 | * This function checks and sets those values and skb->ip_summed: if this |
| 3052 | * returns false you should drop the packet. |
| 3053 | */ |
| 3054 | bool skb_partial_csum_set(struct sk_buff *skb, u16 start, u16 off) |
| 3055 | { |
Herbert Xu | 5ff8dda | 2009-06-04 01:22:01 +0000 | [diff] [blame] | 3056 | if (unlikely(start > skb_headlen(skb)) || |
| 3057 | unlikely((int)start + off > skb_headlen(skb) - 2)) { |
Rusty Russell | f35d9d8 | 2008-02-04 23:49:54 -0500 | [diff] [blame] | 3058 | if (net_ratelimit()) |
| 3059 | printk(KERN_WARNING |
| 3060 | "bad partial csum: csum=%u/%u len=%u\n", |
Herbert Xu | 5ff8dda | 2009-06-04 01:22:01 +0000 | [diff] [blame] | 3061 | start, off, skb_headlen(skb)); |
Rusty Russell | f35d9d8 | 2008-02-04 23:49:54 -0500 | [diff] [blame] | 3062 | return false; |
| 3063 | } |
| 3064 | skb->ip_summed = CHECKSUM_PARTIAL; |
| 3065 | skb->csum_start = skb_headroom(skb) + start; |
| 3066 | skb->csum_offset = off; |
| 3067 | return true; |
| 3068 | } |
David S. Miller | b4ac530fc | 2009-02-10 02:09:24 -0800 | [diff] [blame] | 3069 | EXPORT_SYMBOL_GPL(skb_partial_csum_set); |
Rusty Russell | f35d9d8 | 2008-02-04 23:49:54 -0500 | [diff] [blame] | 3070 | |
Ben Hutchings | 4497b07 | 2008-06-19 16:22:28 -0700 | [diff] [blame] | 3071 | void __skb_warn_lro_forwarding(const struct sk_buff *skb) |
| 3072 | { |
| 3073 | if (net_ratelimit()) |
| 3074 | pr_warning("%s: received packets cannot be forwarded" |
| 3075 | " while LRO is enabled\n", skb->dev->name); |
| 3076 | } |
Ben Hutchings | 4497b07 | 2008-06-19 16:22:28 -0700 | [diff] [blame] | 3077 | EXPORT_SYMBOL(__skb_warn_lro_forwarding); |