Release 4.11 net/core/skbuff.c

/*
 *      Routines having to do with the 'struct sk_buff' memory handlers.
 *
 *      Authors:        Alan Cox <alan@lxorguk.ukuu.org.uk>
 *                      Florian La Roche <rzsfl@rz.uni-sb.de>
 *
 *      Fixes:
 *              Alan Cox        :       Fixed the worst of the load
 *                                      balancer bugs.
 *              Dave Platt      :       Interrupt stacking fix.
 *      Richard Kooijman        :       Timestamp fixes.
 *              Alan Cox        :       Changed buffer format.
 *              Alan Cox        :       destructor hook for AF_UNIX etc.
 *              Linus Torvalds  :       Better skb_clone.
 *              Alan Cox        :       Added skb_copy.
 *              Alan Cox        :       Added all the changed routines Linus
 *                                      only put in the headers
 *              Ray VanTassle   :       Fixed --skb->lock in free
 *              Alan Cox        :       skb_copy copy arp field
 *              Andi Kleen      :       slabified it.
 *              Robert Olsson   :       Removed skb_head_pool
 *
 *      NOTE:
 *              The __skb_ routines should be called with interrupts
 *      disabled, or you better be *real* sure that the operation is atomic
 *      with respect to whatever list is being frobbed (e.g. via lock_sock()
 *      or via disabling bottom half handlers, etc).
 *
 *      This program is free software; you can redistribute it and/or
 *      modify it under the terms of the GNU General Public License
 *      as published by the Free Software Foundation; either version
 *      2 of the License, or (at your option) any later version.
 */

/*
 *      The functions in this file will not compile correctly with gcc 2.4.x
 */


#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/module.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/kmemcheck.h>
#include <linux/mm.h>
#include <linux/interrupt.h>
#include <linux/in.h>
#include <linux/inet.h>
#include <linux/slab.h>
#include <linux/tcp.h>
#include <linux/udp.h>
#include <linux/sctp.h>
#include <linux/netdevice.h>
#ifdef CONFIG_NET_CLS_ACT
#include <net/pkt_sched.h>
#endif
#include <linux/string.h>
#include <linux/skbuff.h>
#include <linux/splice.h>
#include <linux/cache.h>
#include <linux/rtnetlink.h>
#include <linux/init.h>
#include <linux/scatterlist.h>
#include <linux/errqueue.h>
#include <linux/prefetch.h>
#include <linux/if_vlan.h>

#include <net/protocol.h>
#include <net/dst.h>
#include <net/sock.h>
#include <net/checksum.h>
#include <net/ip6_checksum.h>
#include <net/xfrm.h>

#include <linux/uaccess.h>
#include <trace/events/skb.h>
#include <linux/highmem.h>
#include <linux/capability.h>
#include <linux/user_namespace.h>


struct kmem_cache *skbuff_head_cache __read_mostly;

static struct kmem_cache *skbuff_fclone_cache __read_mostly;

int sysctl_max_skb_frags __read_mostly = MAX_SKB_FRAGS;

EXPORT_SYMBOL(sysctl_max_skb_frags);

/**
 *      skb_panic - private function for out-of-line support
 *      @skb:   buffer
 *      @sz:    size
 *      @addr:  address
 *      @msg:   skb_over_panic or skb_under_panic
 *
 *      Out-of-line support for skb_put() and skb_push().
 *      Called via the wrapper skb_over_panic() or skb_under_panic().
 *      Keep out of line to prevent kernel bloat.
 *      __builtin_return_address is not used because it is not always reliable.
 */


static void skb_panic(struct sk_buff *skb, unsigned int sz, void *addr,
		      const char msg[])
{
	pr_emerg("%s: text:%p len:%d put:%d head:%p data:%p tail:%#lx end:%#lx dev:%s\n",
		 msg, addr, skb->len, sz, skb->head, skb->data,
		 (unsigned long)skb->tail, (unsigned long)skb->end,
		 skb->dev ? skb->dev->name : "<NULL>");
	BUG();
}

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Linus Torvalds (pre-git)
40
51.28%
3
30.00%
Patrick McHardy
16
20.51%
1
10.00%
Arnaldo Carvalho de Melo
8
10.26%
2
20.00%
Jean Sacren
8
10.26%
1
10.00%
Joe Perches
3
3.85%
1
10.00%
James Hogan
2
2.56%
1
10.00%
Rami Rosen
1
1.28%
1
10.00%
Total
78
100.00%
10
100.00%



static void skb_over_panic(struct sk_buff *skb, unsigned int sz, void *addr)
{
	skb_panic(skb, sz, addr, __func__);
}

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Linus Torvalds (pre-git)
19
63.33%
1
25.00%
Jean Sacren
9
30.00%
1
25.00%
Rami Rosen
1
3.33%
1
25.00%
Patrick McHardy
1
3.33%
1
25.00%
Total
30
100.00%
4
100.00%



static void skb_under_panic(struct sk_buff *skb, unsigned int sz, void *addr)
{
	skb_panic(skb, sz, addr, __func__);
}

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22
73.33%
1
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Patrick McHardy
4
13.33%
1
25.00%
Linus Torvalds (pre-git)
3
10.00%
1
25.00%
Arnaldo Carvalho de Melo
1
3.33%
1
25.00%
Total
30
100.00%
4
100.00%

/*
 * kmalloc_reserve is a wrapper around kmalloc_node_track_caller that tells
 * the caller if emergency pfmemalloc reserves are being used. If it is and
 * the socket is later found to be SOCK_MEMALLOC then PFMEMALLOC reserves
 * may be used. Otherwise, the packet data may be discarded until enough
 * memory is free
 */

#define kmalloc_reserve(size, gfp, node, pfmemalloc) \
	 __kmalloc_reserve(size, gfp, node, _RET_IP_, pfmemalloc)



static void *__kmalloc_reserve(size_t size, gfp_t flags, int node,
			       unsigned long ip, bool *pfmemalloc)
{
	void *obj;
	bool ret_pfmemalloc = false;

	/*
         * Try a regular allocation, when that fails and we're not entitled
         * to the reserves, fail.
         */
	obj = kmalloc_node_track_caller(size,
					flags | __GFP_NOMEMALLOC | __GFP_NOWARN,
					node);
	if (obj || !(gfp_pfmemalloc_allowed(flags)))
		goto out;

	/* Try again but now we are using pfmemalloc reserves */
	ret_pfmemalloc = true;
	obj = kmalloc_node_track_caller(size, flags, node);

out:
	if (pfmemalloc)
		*pfmemalloc = ret_pfmemalloc;

	return obj;
}

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Mel Gorman
93
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1
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1
50.00%
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94
100.00%
2
100.00%

/*      Allocate a new skbuff. We do this ourselves so we can fill in a few
 *      'private' fields and also do memory statistics to find all the
 *      [BEEP] leaks.
 *
 */



struct sk_buff *__alloc_skb_head(gfp_t gfp_mask, int node)
{
	struct sk_buff *skb;

	/* Get the HEAD */
	skb = kmem_cache_alloc_node(skbuff_head_cache,
				    gfp_mask & ~__GFP_DMA, node);
	if (!skb)
		goto out;

	/*
         * Only clear those fields we need to clear, not those that we will
         * actually initialise below. Hence, don't put any more fields after
         * the tail pointer in struct sk_buff!
         */
	memset(skb, 0, offsetof(struct sk_buff, tail));
	skb->head = NULL;
	skb->truesize = sizeof(struct sk_buff);
	atomic_set(&skb->users, 1);

	skb->mac_header = (typeof(skb->mac_header))~0U;
out:
	return skb;
}

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Patrick McHardy
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Américo Wang
6
5.83%
1
25.00%
David S. Miller
2
1.94%
1
25.00%
Pablo Neira Ayuso
1
0.97%
1
25.00%
Total
103
100.00%
4
100.00%

/**
 *      __alloc_skb     -       allocate a network buffer
 *      @size: size to allocate
 *      @gfp_mask: allocation mask
 *      @flags: If SKB_ALLOC_FCLONE is set, allocate from fclone cache
 *              instead of head cache and allocate a cloned (child) skb.
 *              If SKB_ALLOC_RX is set, __GFP_MEMALLOC will be used for
 *              allocations in case the data is required for writeback
 *      @node: numa node to allocate memory on
 *
 *      Allocate a new &sk_buff. The returned buffer has no headroom and a
 *      tail room of at least size bytes. The object has a reference count
 *      of one. The return is the buffer. On a failure the return is %NULL.
 *
 *      Buffers may only be allocated from interrupts using a @gfp_mask of
 *      %GFP_ATOMIC.
 */


struct sk_buff *__alloc_skb(unsigned int size, gfp_t gfp_mask,
			    int flags, int node)
{
	struct kmem_cache *cache;
	struct skb_shared_info *shinfo;
	struct sk_buff *skb;
	u8 *data;
	bool pfmemalloc;

	cache = (flags & SKB_ALLOC_FCLONE)
		? skbuff_fclone_cache : skbuff_head_cache;

	if (sk_memalloc_socks() && (flags & SKB_ALLOC_RX))
		gfp_mask |= __GFP_MEMALLOC;

	/* Get the HEAD */
	skb = kmem_cache_alloc_node(cache, gfp_mask & ~__GFP_DMA, node);
	if (!skb)
		goto out;
	prefetchw(skb);

	/* We do our best to align skb_shared_info on a separate cache
         * line. It usually works because kmalloc(X > SMP_CACHE_BYTES) gives
         * aligned memory blocks, unless SLUB/SLAB debug is enabled.
         * Both skb->head and skb_shared_info are cache line aligned.
         */
	size = SKB_DATA_ALIGN(size);
	size += SKB_DATA_ALIGN(sizeof(struct skb_shared_info));
	data = kmalloc_reserve(size, gfp_mask, node, &pfmemalloc);
	if (!data)
		goto nodata;
	/* kmalloc(size) might give us more room than requested.
         * Put skb_shared_info exactly at the end of allocated zone,
         * to allow max possible filling before reallocation.
         */
	size = SKB_WITH_OVERHEAD(ksize(data));
	prefetchw(data + size);

	/*
         * Only clear those fields we need to clear, not those that we will
         * actually initialise below. Hence, don't put any more fields after
         * the tail pointer in struct sk_buff!
         */
	memset(skb, 0, offsetof(struct sk_buff, tail));
	/* Account for allocated memory : skb + skb->head */
	skb->truesize = SKB_TRUESIZE(size);
	skb->pfmemalloc = pfmemalloc;
	atomic_set(&skb->users, 1);
	skb->head = data;
	skb->data = data;
	skb_reset_tail_pointer(skb);
	skb->end = skb->tail + size;
	skb->mac_header = (typeof(skb->mac_header))~0U;
	skb->transport_header = (typeof(skb->transport_header))~0U;

	/* make sure we initialize shinfo sequentially */
	shinfo = skb_shinfo(skb);
	memset(shinfo, 0, offsetof(struct skb_shared_info, dataref));
	atomic_set(&shinfo->dataref, 1);
	kmemcheck_annotate_variable(shinfo->destructor_arg);

	if (flags & SKB_ALLOC_FCLONE) {
		struct sk_buff_fclones *fclones;

		fclones = container_of(skb, struct sk_buff_fclones, skb1);

		kmemcheck_annotate_bitfield(&fclones->skb2, flags1);
		skb->fclone = SKB_FCLONE_ORIG;
		atomic_set(&fclones->fclone_ref, 1);

		fclones->skb2.fclone = SKB_FCLONE_CLONE;
	}
out:
	return skb;
nodata:
	kmem_cache_free(cache, skb);
	skb = NULL;
	goto out;
}
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83
22.13%
6
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70
18.67%
14
31.82%
David S. Miller
47
12.53%
4
9.09%
Mel Gorman
37
9.87%
1
2.27%
Ian Pratt
21
5.60%
1
2.27%
Benjamin LaHaise
20
5.33%
1
2.27%
Mala Anand
15
4.00%
1
2.27%
Américo Wang
12
3.20%
1
2.27%
Herbert Xu
11
2.93%
1
2.27%
Linus Torvalds
10
2.67%
2
4.55%
Arnaldo Carvalho de Melo
10
2.67%
4
9.09%
Christoph Hellwig
8
2.13%
1
2.27%
Patrick Ohly
7
1.87%
1
2.27%
Tony Lindgren
7
1.87%
1
2.27%
Stephen Hemminger
7
1.87%
1
2.27%
Vegard Nossum
6
1.60%
1
2.27%
Christoph Lameter
2
0.53%
1
2.27%
Al Viro
1
0.27%
1
2.27%
Johannes Berg
1
0.27%
1
2.27%
Total
375
100.00%
44
100.00%


EXPORT_SYMBOL(__alloc_skb);

/**
 * __build_skb - build a network buffer
 * @data: data buffer provided by caller
 * @frag_size: size of data, or 0 if head was kmalloced
 *
 * Allocate a new &sk_buff. Caller provides space holding head and
 * skb_shared_info. @data must have been allocated by kmalloc() only if
 * @frag_size is 0, otherwise data should come from the page allocator
 *  or vmalloc()
 * The return is the new skb buffer.
 * On a failure the return is %NULL, and @data is not freed.
 * Notes :
 *  Before IO, driver allocates only data buffer where NIC put incoming frame
 *  Driver should add room at head (NET_SKB_PAD) and
 *  MUST add room at tail (SKB_DATA_ALIGN(skb_shared_info))
 *  After IO, driver calls build_skb(), to allocate sk_buff and populate it
 *  before giving packet to stack.
 *  RX rings only contains data buffers, not full skbs.
 */


struct sk_buff *__build_skb(void *data, unsigned int frag_size)
{
	struct skb_shared_info *shinfo;
	struct sk_buff *skb;
	unsigned int size = frag_size ? : ksize(data);

	skb = kmem_cache_alloc(skbuff_head_cache, GFP_ATOMIC);
	if (!skb)
		return NULL;

	size -= SKB_DATA_ALIGN(sizeof(struct skb_shared_info));

	memset(skb, 0, offsetof(struct sk_buff, tail));
	skb->truesize = SKB_TRUESIZE(size);
	atomic_set(&skb->users, 1);
	skb->head = data;
	skb->data = data;
	skb_reset_tail_pointer(skb);
	skb->end = skb->tail + size;
	skb->mac_header = (typeof(skb->mac_header))~0U;
	skb->transport_header = (typeof(skb->transport_header))~0U;

	/* make sure we initialize shinfo sequentially */
	shinfo = skb_shinfo(skb);
	memset(shinfo, 0, offsetof(struct skb_shared_info, dataref));
	atomic_set(&shinfo->dataref, 1);
	kmemcheck_annotate_variable(shinfo->destructor_arg);

	return skb;
}

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Eric Dumazet
183
91.96%
4
66.67%
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12
6.03%
1
16.67%
David S. Miller
4
2.01%
1
16.67%
Total
199
100.00%
6
100.00%

/* build_skb() is wrapper over __build_skb(), that specifically
 * takes care of skb->head and skb->pfmemalloc
 * This means that if @frag_size is not zero, then @data must be backed
 * by a page fragment, not kmalloc() or vmalloc()
 */


struct sk_buff *build_skb(void *data, unsigned int frag_size)
{
	struct sk_buff *skb = __build_skb(data, frag_size);

	if (skb && frag_size) {
		skb->head_frag = 1;
		if (page_is_pfmemalloc(virt_to_head_page(data)))
			skb->pfmemalloc = 1;
	}
	return skb;
}
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57
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3
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1
50.00%
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60
100.00%
2
100.00%


EXPORT_SYMBOL(build_skb);


#define NAPI_SKB_CACHE_SIZE	64


struct napi_alloc_cache {
	
struct page_frag_cache page;
	
unsigned int skb_count;
	
void *skb_cache[NAPI_SKB_CACHE_SIZE];
};

static DEFINE_PER_CPU(struct page_frag_cache, netdev_alloc_cache);
static DEFINE_PER_CPU(struct napi_alloc_cache, napi_alloc_cache);



static void *__netdev_alloc_frag(unsigned int fragsz, gfp_t gfp_mask)
{
	struct page_frag_cache *nc;
	unsigned long flags;
	void *data;

	local_irq_save(flags);
	nc = this_cpu_ptr(&netdev_alloc_cache);
	data = page_frag_alloc(nc, fragsz, gfp_mask);
	local_irq_restore(flags);
	return data;
}

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47
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4
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Eric Dumazet
12
20.34%
2
33.33%
Total
59
100.00%
6
100.00%

/**
 * netdev_alloc_frag - allocate a page fragment
 * @fragsz: fragment size
 *
 * Allocates a frag from a page for receive buffer.
 * Uses GFP_ATOMIC allocations.
 */


void *netdev_alloc_frag(unsigned int fragsz)
{
	return __netdev_alloc_frag(fragsz, GFP_ATOMIC | __GFP_COLD);
}
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20
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EXPORT_SYMBOL(netdev_alloc_frag);



static void *__napi_alloc_frag(unsigned int fragsz, gfp_t gfp_mask)
{
	struct napi_alloc_cache *nc = this_cpu_ptr(&napi_alloc_cache);

	return page_frag_alloc(&nc->page, fragsz, gfp_mask);
}

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4
10.53%
1
25.00%
Total
38
100.00%
4
100.00%



void *napi_alloc_frag(unsigned int fragsz)
{
	return __napi_alloc_frag(fragsz, GFP_ATOMIC | __GFP_COLD);
}
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EXPORT_SYMBOL(napi_alloc_frag);

/**
 *      __netdev_alloc_skb - allocate an skbuff for rx on a specific device
 *      @dev: network device to receive on
 *      @len: length to allocate
 *      @gfp_mask: get_free_pages mask, passed to alloc_skb
 *
 *      Allocate a new &sk_buff and assign it a usage count of one. The
 *      buffer has NET_SKB_PAD headroom built in. Users should allocate
 *      the headroom they think they need without accounting for the
 *      built in space. The built in space is used for optimisations.
 *
 *      %NULL is returned if there is no free memory.
 */


struct sk_buff *__netdev_alloc_skb(struct net_device *dev, unsigned int len,
				   gfp_t gfp_mask)
{
	struct page_frag_cache *nc;
	unsigned long flags;
	struct sk_buff *skb;
	bool pfmemalloc;
	void *data;

	len += NET_SKB_PAD;

	if ((len > SKB_WITH_OVERHEAD(PAGE_SIZE)) ||
	    (gfp_mask & (__GFP_DIRECT_RECLAIM | GFP_DMA))) {
		skb = __alloc_skb(len, gfp_mask, SKB_ALLOC_RX, NUMA_NO_NODE);
		if (!skb)
			goto skb_fail;
		goto skb_success;
	}

	len += SKB_DATA_ALIGN(sizeof(struct skb_shared_info));
	len = SKB_DATA_ALIGN(len);

	if (sk_memalloc_socks())
		gfp_mask |= __GFP_MEMALLOC;

	local_irq_save(flags);

	nc = this_cpu_ptr(&netdev_alloc_cache);
	data = page_frag_alloc(nc, len, gfp_mask);
	pfmemalloc = nc->pfmemalloc;

	local_irq_restore(flags);

	if (unlikely(!data))
		return NULL;

	skb = __build_skb(data, len);
	if (unlikely(!skb)) {
		skb_free_frag(data);
		return NULL;
	}

	/* use OR instead of assignment to avoid clearing of bits in mask */
	if (pfmemalloc)
		skb->pfmemalloc = 1;
	skb->head_frag = 1;

skb_success:
	skb_reserve(skb, NET_SKB_PAD);
	skb->dev = dev;

skb_fail:
	return skb;
}
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56
24.56%
3
23.08%
Christoph Hellwig
17
7.46%
2
15.38%
Mel Gorman
11
4.82%
2
15.38%
Total
228
100.00%
13
100.00%


EXPORT_SYMBOL(__netdev_alloc_skb);

/**
 *      __napi_alloc_skb - allocate skbuff for rx in a specific NAPI instance
 *      @napi: napi instance this buffer was allocated for
 *      @len: length to allocate
 *      @gfp_mask: get_free_pages mask, passed to alloc_skb and alloc_pages
 *
 *      Allocate a new sk_buff for use in NAPI receive.  This buffer will
 *      attempt to allocate the head from a special reserved region used
 *      only for NAPI Rx allocation.  By doing this we can save several
 *      CPU cycles by avoiding having to disable and re-enable IRQs.
 *
 *      %NULL is returned if there is no free memory.
 */


struct sk_buff *__napi_alloc_skb(struct napi_struct *napi, unsigned int len,
				 gfp_t gfp_mask)
{
	struct napi_alloc_cache *nc = this_cpu_ptr(&napi_alloc_cache);
	struct sk_buff *skb;
	void *data;

	len += NET_SKB_PAD + NET_IP_ALIGN;

	if ((len > SKB_WITH_OVERHEAD(PAGE_SIZE)) ||
	    (gfp_mask & (__GFP_DIRECT_RECLAIM | GFP_DMA))) {
		skb = __alloc_skb(len, gfp_mask, SKB_ALLOC_RX, NUMA_NO_NODE);
		if (!skb)
			goto skb_fail;
		goto skb_success;
	}

	len += SKB_DATA_ALIGN(sizeof(struct skb_shared_info));
	len = SKB_DATA_ALIGN(len);

	if (sk_memalloc_socks())
		gfp_mask |= __GFP_MEMALLOC;

	data = page_frag_alloc(&nc->page, len, gfp_mask);
	if (unlikely(!data))
		return NULL;

	skb = __build_skb(data, len);
	if (unlikely(!skb)) {
		skb_free_frag(data);
		return NULL;
	}

	/* use OR instead of assignment to avoid clearing of bits in mask */
	if (nc->page.pfmemalloc)
		skb->pfmemalloc = 1;
	skb->head_frag = 1;

skb_success:
	skb_reserve(skb, NET_SKB_PAD + NET_IP_ALIGN);
	skb->dev = napi->dev;

skb_fail:
	return skb;
}
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1
14.29%
Mel Gorman
1
0.46%
1
14.29%
Total
216
100.00%
7
100.00%


EXPORT_SYMBOL(__napi_alloc_skb);



void skb_add_rx_frag(struct sk_buff *skb, int i, struct page *page, int off,
		     int size, unsigned int truesize)
{
	skb_fill_page_desc(skb, i, page, off, size);
	skb->len += size;
	skb->data_len += size;
	skb->truesize += truesize;
}
Contributors
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Peter Zijlstra
54
91.53%
1
50.00%
Eric Dumazet
5
8.47%
1
50.00%
Total
59
100.00%
2
100.00%


EXPORT_SYMBOL(skb_add_rx_frag);



void skb_coalesce_rx_frag(struct sk_buff *skb, int i, int size,
			  unsigned int truesize)
{
	skb_frag_t *frag = &skb_shinfo(skb)->frags[i];

	skb_frag_size_add(frag, size);
	skb->len += size;
	skb->data_len += size;
	skb->truesize += truesize;
}
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Jason (Hui) Wang
60
100.00%
1
100.00%
Total
60
100.00%
1
100.00%


EXPORT_SYMBOL(skb_coalesce_rx_frag);



static void skb_drop_list(struct sk_buff **listp)
{
	kfree_skb_list(*listp);
	*listp = NULL;
}

Contributors
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Linus Torvalds
11
47.83%
1
25.00%
Herbert Xu
7
30.43%
1
25.00%
Eric Dumazet
4
17.39%
1
25.00%
Linus Torvalds (pre-git)
1
4.35%
1
25.00%
Total
23
100.00%
4
100.00%



static inline void skb_drop_fraglist(struct sk_buff *skb)
{
	skb_drop_list(&skb_shinfo(skb)->frag_list);
}

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Herbert Xu
23
100.00%
1
100.00%
Total
23
100.00%
1
100.00%



static void skb_clone_fraglist(struct sk_buff *skb)
{
	struct sk_buff *list;

	skb_walk_frags(skb, list)
		skb_get(list);
}

Contributors
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Linus Torvalds
23
85.19%
1
50.00%
David S. Miller
4
14.81%
1
50.00%
Total
27
100.00%
2
100.00%



static void skb_free_head(struct sk_buff *skb)
{
	unsigned char *head = skb->head;

	if (skb->head_frag)
		skb_free_frag(head);
	else
		kfree(head);
}

Contributors
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Eric Dumazet
27
72.97%
1
50.00%
Alexander Duyck
10
27.03%
1
50.00%
Total
37
100.00%
2
100.00%



static void skb_release_data(struct sk_buff *skb)
{
	struct skb_shared_info *shinfo = skb_shinfo(skb);
	int i;

	if (skb->cloned &&
	    atomic_sub_return(skb->nohdr ? (1 << SKB_DATAREF_SHIFT) + 1 : 1,
			      &shinfo->dataref))
		return;

	for (i = 0; i < shinfo->nr_frags; i++)
		__skb_frag_unref(&shinfo->frags[i]);

	/*
         * If skb buf is from userspace, we need to notify the caller
         * the lower device DMA has done;
         */
	if (shinfo->tx_flags & SKBTX_DEV_ZEROCOPY) {
		struct ubuf_info *uarg;

		uarg = shinfo->destructor_arg;
		if (uarg->callback)
			uarg->callback(uarg, true);
	}

	if (shinfo->frag_list)
		kfree_skb_list(shinfo->frag_list);

	skb_free_head(skb);
}

Contributors
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CommitProp
Eric Dumazet
35
26.12%
2
20.00%
Shirley Ma
32
23.88%
1
10.00%
Linus Torvalds
30
22.39%
1
10.00%
Linus Torvalds (pre-git)
19
14.18%
3
30.00%
Herbert Xu
15
11.19%
1
10.00%
Michael S. Tsirkin
2
1.49%
1
10.00%
Adrian Bunk
1
0.75%
1
10.00%
Total
134
100.00%
10
100.00%

/*
 *      Free an skbuff by memory without cleaning the state.
 */


static void kfree_skbmem(struct sk_buff *skb)
{
	struct sk_buff_fclones *fclones;

	switch (skb->fclone) {
	case SKB_FCLONE_UNAVAILABLE:
		kmem_cache_free(skbuff_head_cache, skb);
		return;

	case SKB_FCLONE_ORIG:
		fclones = container_of(skb, struct sk_buff_fclones, skb1);

		/* We usually free the clone (TX completion) before original skb
                 * This test would have no chance to be true for the clone,
                 * while here, branch prediction will be good.
                 */
		if (atomic_read(&fclones->fclone_ref) == 1)
			goto fastpath;
		break;

	default: /* SKB_FCLONE_CLONE */
		fclones = container_of(skb, struct sk_buff_fclones, skb2);
		break;
	}
	if (!atomic_dec_and_test(&fclones->fclone_ref))
		return;
fastpath:
	kmem_cache_free(skbuff_fclone_cache, fclones);
}

Contributors
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Tokens
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CommitProp
Eric Dumazet
43
41.75%
2
25.00%
David S. Miller
42
40.78%
1
12.50%
Linus Torvalds
9
8.74%
1
12.50%
Linus Torvalds (pre-git)
5
4.85%
2
25.00%
Robert Olsson
3
2.91%
1
12.50%
Herbert Xu
1
0.97%
1
12.50%
Total
103
100.00%
8
100.00%



static void skb_release_head_state(struct sk_buff *skb)
{
	skb_dst_drop(skb);
#ifdef CONFIG_XFRM
	secpath_put(skb->sp);
#endif
	if (skb->destructor) {
		WARN_ON(in_irq());
		skb->destructor(skb);
	}
#if IS_ENABLED(CONFIG_NF_CONNTRACK)
	nf_conntrack_put(skb_nfct(skb));
#endif
#if IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
	nf_bridge_put(skb->nf_bridge);
#endif
}

Contributors
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Tokens
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Linus Torvalds (pre-git)
31
38.75%
7
31.82%
Yasuyuki Kozakai
10
12.50%
2
9.09%
Bart De Schuymer
10
12.50%
2
9.09%
Alexey Kuznetsov
7
8.75%
1
4.55%
Pablo Neira Ayuso
5
6.25%
1
4.55%
Tomas Szepe
4
5.00%
1
4.55%
Florian Westphal
3
3.75%
1
4.55%
KOVACS Krisztian
2
2.50%
1
4.55%
Lennert Buytenhek
2
2.50%
1
4.55%
Stephen Hemminger
2
2.50%
1
4.55%
Igor Maravić
1
1.25%
1
4.55%
Eric Dumazet
1
1.25%
1
4.55%
Herbert Xu
1
1.25%
1
4.55%
Andi Kleen
1
1.25%
1
4.55%
Total
80
100.00%
22
100.00%

/* Free everything but the sk_buff shell. */


static void skb_release_all(struct sk_buff *skb)
{
	skb_release_head_state(skb);
	if (likely(skb->head))
		skb_release_data(skb);
}

Contributors
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CommitProp
Lennert Buytenhek
15
50.00%
1
25.00%
Patrick McHardy
8
26.67%
1
25.00%
Herbert Xu
6
20.00%
1
25.00%
Pablo Neira Ayuso
1
3.33%
1
25.00%
Total
30
100.00%
4
100.00%

/**
 *      __kfree_skb - private function
 *      @skb: buffer
 *
 *      Free an sk_buff. Release anything attached to the buffer.
 *      Clean the state. This is an internal helper function. Users should
 *      always call kfree_skb
 */



void __kfree_skb(struct sk_buff *skb)
{
	skb_release_all(skb);
	kfree_skbmem(skb);
}
Contributors
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Tokens
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Herbert Xu
14
70.00%
1
25.00%
Linus Torvalds (pre-git)
6
30.00%
3
75.00%
Total
20
100.00%
4
100.00%


EXPORT_SYMBOL(__kfree_skb);

/**
 *      kfree_skb - free an sk_buff
 *      @skb: buffer to free
 *
 *      Drop a reference to the buffer and free it if the usage count has
 *      hit zero.
 */


void kfree_skb(struct sk_buff *skb)
{
	if (unlikely(!skb))
		return;
	if (likely(atomic_read(&skb->users) == 1))
		smp_rmb();
	else if (likely(!atomic_dec_and_test(&skb->users)))
		return;
	trace_kfree_skb(skb, __builtin_return_address(0));
	__kfree_skb(skb);
}
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Jörn Engel
58
85.29%
1
50.00%
Neil Horman
10
14.71%
1
50.00%
Total
68
100.00%
2
100.00%


EXPORT_SYMBOL(kfree_skb);



void kfree_skb_list(struct sk_buff *segs)
{
	while (segs) {
		struct sk_buff *next = segs->next;

		kfree_skb(segs);
		segs = next;
	}
}
Contributors
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Eric Dumazet
34
100.00%
1
100.00%
Total
34
100.00%
1
100.00%


EXPORT_SYMBOL(kfree_skb_list);

/**
 *      skb_tx_error - report an sk_buff xmit error
 *      @skb: buffer that triggered an error
 *
 *      Report xmit error if a device callback is tracking this skb.
 *      skb must be freed afterwards.
 */


void skb_tx_error(struct sk_buff *skb)
{
	if (skb_shinfo(skb)->tx_flags & SKBTX_DEV_ZEROCOPY) {
		struct ubuf_info *uarg;

		uarg = skb_shinfo(skb)->destructor_arg;
		if (uarg->callback)
			uarg->callback(uarg, false);
		skb_shinfo(skb)->tx_flags &= ~SKBTX_DEV_ZEROCOPY;
	}
}
Contributors
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Michael S. Tsirkin
62
100.00%
1
100.00%
Total
62
100.00%
1
100.00%


EXPORT_SYMBOL(skb_tx_error);

/**
 *      consume_skb - free an skbuff
 *      @skb: buffer to free
 *
 *      Drop a ref to the buffer and free it if the usage count has hit zero
 *      Functions identically to kfree_skb, but kfree_skb assumes that the frame
 *      is being dropped after a failure and notes that
 */


void consume_skb(struct sk_buff *skb)
{
	if (unlikely(!skb))
		return;
	if (likely(atomic_read(&skb->users) == 1))
		smp_rmb();
	else if (likely(!atomic_dec_and_test(&skb->users)))
		return;
	trace_consume_skb(skb);
	__kfree_skb(skb);
}
Contributors
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Neil Horman
58
92.06%
1
50.00%
Koki Sanagi
5
7.94%
1
50.00%
Total
63
100.00%
2
100.00%


EXPORT_SYMBOL(consume_skb);



void __kfree_skb_flush(void)
{
	struct napi_alloc_cache *nc = this_cpu_ptr(&napi_alloc_cache);

	/* flush skb_cache if containing objects */
	if (nc->skb_count) {
		kmem_cache_free_bulk(skbuff_head_cache, nc->skb_count,
				     nc->skb_cache);
		nc->skb_count = 0;
	}
}

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Jesper Dangaard Brouer
46
100.00%
1
100.00%
Total
46
100.00%
1
100.00%



static inline void _kfree_skb_defer(struct sk_buff *skb)
{
	struct napi_alloc_cache *nc = this_cpu_ptr(&napi_alloc_cache);

	/* drop skb->head and call any destructors for packet */
	skb_release_all(skb);

	/* record skb to CPU local list */
	nc->skb_cache[nc->skb_count++] = skb;

#ifdef CONFIG_SLUB
	/* SLUB writes into objects when freeing */
	prefetchw(skb);
#endif

	/* flush skb_cache if it is filled */
	if (unlikely(nc->skb_count == NAPI_SKB_CACHE_SIZE)) {
		kmem_cache_free_bulk(skbuff_head_cache, NAPI_SKB_CACHE_SIZE,
				     nc->skb_cache);
		nc->skb_count = 0;
	}
}
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Jesper Dangaard Brouer
84
100.00%
2
100.00%
Total
84
100.00%
2
100.00%



void __kfree_skb_defer(struct sk_buff *skb)
{
	_kfree_skb_defer(skb);
}

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Jesper Dangaard Brouer
15
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1
100.00%
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15
100.00%
1
100.00%



void napi_consume_skb(struct sk_buff *skb, int budget)
{
	if (unlikely(!skb))
		return;

	/* Zero budget indicate non-NAPI context called us, like netpoll */
	if (unlikely(!budget)) {
		dev_consume_skb_any(skb);
		return;
	}

	if (likely(atomic_read(&skb->users) == 1))
		smp_rmb();
	else if (likely(!atomic_dec_and_test(&skb->users)))
		return;
	/* if reaching here SKB is ready to free */
	trace_consume_skb(skb);

	/* if SKB is a clone, don't handle this case */
	if (skb->fclone != SKB_FCLONE_UNAVAILABLE) {
		__kfree_skb(skb);
		return;
	}

	_kfree_skb_defer(skb);
}
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Jesper Dangaard Brouer
101
100.00%
3
100.00%
Total
101
100.00%
3
100.00%


EXPORT_SYMBOL(napi_consume_skb);

/* Make sure a field is enclosed inside headers_start/headers_end section */

#define CHECK_SKB_FIELD(field) \
	BUILD_BUG_ON(offsetof(struct sk_buff, field) <          \
                     offsetof(struct sk_buff, headers_start));  \
        BUILD_BUG_ON(offsetof(struct sk_buff, field) >          \
                     offsetof(struct sk_buff, headers_end));    \

static void __copy_skb_header(struct sk_buff *new, const struct sk_buff *old)
{
	new->tstamp		= old->tstamp;
	/* We do not copy old->sk */
	new->dev		= old->dev;
	memcpy(new->cb, old->cb, sizeof(old->cb));
	skb_dst_copy(new, old);
#ifdef CONFIG_XFRM
	new->sp			= secpath_get(old->sp);
#endif
	__nf_copy(new, old, false);

	/* Note : this field could be in headers_start/headers_end section
         * It is not yet because we do not want to have a 16 bit hole
         */
	new->queue_mapping = old->queue_mapping;

	memcpy(&new->headers_start, &old->headers_start,
	       offsetof(struct sk_buff, headers_end) -
	       offsetof(struct sk_buff, headers_start));
	CHECK_SKB_FIELD(protocol);
	CHECK_SKB_FIELD(csum);
	CHECK_SKB_FIELD(hash);
	CHECK_SKB_FIELD(priority);
	CHECK_SKB_FIELD(skb_iif);
	CHECK_SKB_FIELD(vlan_proto);
	CHECK_SKB_FIELD(vlan_tci);
	CHECK_SKB_FIELD(transport_header);
	CHECK_SKB_FIELD(network_header);
	CHECK_SKB_FIELD(mac_header);
	CHECK_SKB_FIELD(inner_protocol);
	CHECK_SKB_FIELD(inner_transport_header);
	CHECK_SKB_FIELD(inner_network_header);
	CHECK_SKB_FIELD(inner_mac_header);
	CHECK_SKB_FIELD(mark);
#ifdef CONFIG_NETWORK_SECMARK
	CHECK_SKB_FIELD(secmark);
#endif
#ifdef CONFIG_NET_RX_BUSY_POLL
	CHECK_SKB_FIELD(napi_id);
#endif
#ifdef CONFIG_XPS
	CHECK_SKB_FIELD(sender_cpu);
#endif
#ifdef CONFIG_NET_SCHED
	CHECK_SKB_FIELD(tc_index);
#endif

}

/*
 * You should not add any new code to this function.  Add it to
 * __copy_skb_header above instead.
 */


static struct sk_buff *__skb_clone(struct sk_buff *n, struct sk_buff *skb)
{

#define C(x) n->x = skb->x

	n->next = n->prev = NULL;
	n->sk = NULL;
	__copy_skb_header(n, skb);

	C(len);
	C(data_len);
	C(mac_len);
	n->hdr_len = skb->nohdr ? skb_headroom(skb) : skb->hdr_len;
	n->cloned = 1;
	n->nohdr = 0;
	n->destructor = NULL;
	C(tail);
	C(end);
	C(head);
	C(head_frag);
	C(data);
	C(truesize);
	atomic_set(&n->users, 1);

	atomic_inc(&(skb_shinfo(skb)->dataref));
	skb->cloned = 1;

	return n;

#undef C
}

Contributors
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CommitProp
Herbert Xu
109
66.87%
2
28.57%
David S. Miller
20
12.27%
1
14.29%
Paul Moore
20
12.27%
1
14.29%
Linus Torvalds
8
4.91%
1
14.29%
Eric Dumazet
5
3.07%
1
14.29%
Linus Torvalds (pre-git)
1
0.61%
1
14.29%
Total
163
100.00%
7
100.00%

/**
 *      skb_morph       -       morph one skb into another
 *      @dst: the skb to receive the contents
 *      @src: the skb to supply the contents
 *
 *      This is identical to skb_clone except that the target skb is
 *      supplied by the user.
 *
 *      The target skb is returned upon exit.
 */


struct sk_buff *skb_morph(struct sk_buff *dst, struct sk_buff *src)
{
	skb_release_all(dst);
	return __skb_clone(dst, src);
}
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Herbert Xu
30
100.00%
2
100.00%
Total
30
100.00%
2
100.00%


EXPORT_SYMBOL_GPL(skb_morph);

/**
 *      skb_copy_ubufs  -       copy userspace skb frags buffers to kernel
 *      @skb: the skb to modify
 *      @gfp_mask: allocation priority
 *
 *      This must be called on SKBTX_DEV_ZEROCOPY skb.
 *      It will copy all frags into kernel and drop the reference
 *      to userspace pages.
 *
 *      If this function is called from an interrupt gfp_mask() must be
 *      %GFP_ATOMIC.
 *
 *      Returns 0 on success or a negative error code on failure
 *      to allocate kernel memory to copy to.
 */


int skb_copy_ubufs(struct sk_buff *skb, gfp_t gfp_mask)
{
	int i;
	int num_frags = skb_shinfo(skb)->nr_frags;
	struct page *page, *head = NULL;
	struct ubuf_info *uarg = skb_shinfo(skb)->destructor_arg;

	for (i = 0; i < num_frags; i++) {
		u8 *vaddr;
		skb_frag_t *f = &skb_shinfo(skb)->frags[i];

		page = alloc_page(gfp_mask);
		if (!page) {
			while (head) {
				struct page *next = (struct page *)page_private(head);
				put_page(head);
				head = next;
			}
			return -ENOMEM;
		}
		vaddr = kmap_atomic(skb_frag_page(f));
		memcpy(page_address(page),
		       vaddr + f->page_offset, skb_frag_size(f));
		kunmap_atomic(vaddr);
		set_page_private(page, (unsigned long)head);
		head = page;
	}

	/* skb frags release userspace buffers */
	for (i = 0; i < num_frags; i++)
		skb_frag_unref(skb, i);

	uarg->callback(uarg, false);

	/* skb frags point to kernel buffers */
	for (i = num_frags - 1; i >= 0; i--) {
		__skb_fill_page_desc(skb, i, head, 0,
				     skb_shinfo(skb)->frags[i].size);
		head = (struct page *)page_private(head);
	}

	skb_shinfo(skb)->tx_flags &= ~SKBTX_DEV_ZEROCOPY;
	return 0;
}
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CommitProp
Shirley Ma
230
83.64%
1
12.50%
Michael S. Tsirkin
12
4.36%
2
25.00%
Ian Campbell
10
3.64%
1
12.50%
Sunghan Suh
10
3.64%
1
12.50%
Eric Dumazet
7
2.55%
2
25.00%
Krishna Kumar
6
2.18%
1
12.50%
Total
275
100.00%
8
100.00%


EXPORT_SYMBOL_GPL(skb_copy_ubufs);

/**
 *      skb_clone       -       duplicate an sk_buff
 *      @skb: buffer to clone
 *      @gfp_mask: allocation priority
 *
 *      Duplicate an &sk_buff. The new one is not owned by a socket. Both
 *      copies share the same packet data but not structure. The new
 *      buffer has a reference count of 1. If the allocation fails the
 *      function returns %NULL otherwise the new buffer is returned.
 *
 *      If this function is called from an interrupt gfp_mask() must be
 *      %GFP_ATOMIC.
 */



struct sk_buff *skb_clone(struct sk_buff *skb, gfp_t gfp_mask)
{
	struct sk_buff_fclones *fclones = container_of(skb,
						       struct sk_buff_fclones,
						       skb1);
	struct sk_buff *n;

	if (skb_orphan_frags(skb, gfp_mask))
		return NULL;

	if (skb->fclone == SKB_FCLONE_ORIG &&
	    atomic_read(&fclones->fclone_ref) == 1) {
		n = &fclones->skb2;
		atomic_set(&fclones->fclone_ref, 2);
	} else {
		if (skb_pfmemalloc(skb))
			gfp_mask |= __GFP_MEMALLOC;

		n = kmem_cache_alloc(skbuff_head_cache, gfp_mask);
		if (!n)
			return NULL;

		kmemcheck_annotate_bitfield(n, flags1);
		n->fclone = SKB_FCLONE_UNAVAILABLE;
	}

	return __skb_clone(n, skb);
}
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CommitProp
Herbert Xu
73
53.68%
1
12.50%
Eric Dumazet
32
23.53%
2
25.00%
Mel Gorman
11
8.09%
1
12.50%
Shirley Ma
11
8.09%
1
12.50%
Vegard Nossum
7
5.15%
1
12.50%
Linus Torvalds (pre-git)
1
0.74%
1
12.50%
Michael S. Tsirkin
1
0.74%
1
12.50%
Total
136
100.00%
8
100.00%


EXPORT_SYMBOL(skb_clone);



static void skb_headers_offset_update(struct sk_buff *skb, int off)
{
	/* Only adjust this if it actually is csum_start rather than csum */
	if (skb->ip_summed == CHECKSUM_PARTIAL)
		skb->csum_start += off;
	/* {transport,network,mac}_header and tail are relative to skb->head */
	skb->transport_header += off;
	skb->network_header   += off;
	if (skb_mac_header_was_set(skb))
		skb->mac_header += off;
	skb->inner_transport_header += off;
	skb->inner_network_header += off;
	skb->inner_mac_header += off;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Pravin B Shelar
58
79.45%
2
66.67%
Eric Dumazet
15
20.55%
1
33.33%
Total
73
100.00%
3
100.00%



static void copy_skb_header(struct sk_buff *new, const struct sk_buff *old)
{
	__copy_skb_header(new, old);

	skb_shinfo(new)->gso_size = skb_shinfo(old)->gso_size;
	skb_shinfo(new)->gso_segs = skb_shinfo(old)->gso_segs;
	skb_shinfo(new)->gso_type = skb_shinfo(old)->gso_type;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Herbert Xu
43
65.15%
3
42.86%
Linus Torvalds (pre-git)
17
25.76%
3
42.86%
Peter P. Waskiewicz Jr
6
9.09%
1
14.29%
Total
66
100.00%
7
100.00%



static inline int skb_alloc_rx_flag(const struct sk_buff *skb)
{
	if (skb_pfmemalloc(skb))
		return SKB_ALLOC_RX;
	return 0;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Mel Gorman
26
100.00%
1
100.00%
Total
26
100.00%
1
100.00%

/**
 *      skb_copy        -       create private copy of an sk_buff
 *      @skb: buffer to copy
 *      @gfp_mask: allocation priority
 *
 *      Make a copy of both an &sk_buff and its data. This is used when the
 *      caller wishes to modify the data and needs a private copy of the
 *      data to alter. Returns %NULL on failure or the pointer to the buffer
 *      on success. The returned buffer has a reference count of 1.
 *
 *      As by-product this function converts non-linear &sk_buff to linear
 *      one, so that &sk_buff becomes completely private and caller is allowed
 *      to modify all the data of returned buffer. This means that this
 *      function is not recommended for use in circumstances when only
 *      header is going to be modified. Use pskb_copy() instead.
 */



struct sk_buff *skb_copy(const struct sk_buff *skb, gfp_t gfp_mask)
{
	int headerlen = skb_headroom(skb);
	unsigned int size = skb_end_offset(skb) + skb->data_len;
	struct sk_buff *n = __alloc_skb(size, gfp_mask,
					skb_alloc_rx_flag(skb), NUMA_NO_NODE);

	if (!n)
		return NULL;

	/* Set the data pointer */
	skb_reserve(n, headerlen);
	/* Set the tail pointer and length */
	skb_put(n, skb->len);

	if (skb_copy_bits(skb, -headerlen, n->head, headerlen + skb->len))
		BUG();

	copy_skb_header(n, skb);
	return n;
}
Contributors
Person
Tokens
Prop
Commits
CommitProp
Linus Torvalds (pre-git)
59
51.30%
5
41.67%
Linus Torvalds
26
22.61%
1
8.33%
Eric Dumazet
16
13.91%
1
8.33%
Mel Gorman
8
6.96%
1
8.33%
Arnaldo Carvalho de Melo
4
3.48%
2
16.67%
Al Viro
1
0.87%
1
8.33%
Alexander Duyck
1
0.87%
1
8.33%
Total
115
100.00%
12
100.00%


EXPORT_SYMBOL(skb_copy);

/**
 *      __pskb_copy_fclone      -  create copy of an sk_buff with private head.
 *      @skb: buffer to copy
 *      @headroom: headroom of new skb
 *      @gfp_mask: allocation priority
 *      @fclone: if true allocate the copy of the skb from the fclone
 *      cache instead of the head cache; it is recommended to set this
 *      to true for the cases where the copy will likely be cloned
 *
 *      Make a copy of both an &sk_buff and part of its data, located
 *      in header. Fragmented data remain shared. This is used when
 *      the caller wishes to modify only header of &sk_buff and needs
 *      private copy of the header to alter. Returns %NULL on failure
 *      or the pointer to the buffer on success.
 *      The returned buffer has a reference count of 1.
 */



struct sk_buff *__pskb_copy_fclone(struct sk_buff *skb, int headroom,
				   gfp_t gfp_mask, bool fclone)
{
	unsigned int size = skb_headlen(skb) + headroom;
	int flags = skb_alloc_rx_flag(skb) | (fclone ? SKB_ALLOC_FCLONE : 0);
	struct sk_buff *n = __alloc_skb(size, gfp_mask, flags, NUMA_NO_NODE);

	if (!n)
		goto out;

	/* Set the data pointer */
	skb_reserve(n, headroom);
	/* Set the tail pointer and length */
	skb_put(n, skb_headlen(skb));
	/* Copy the bytes */
	skb_copy_from_linear_data(skb, n->data, n->len);

	n->truesize += skb->data_len;
	n->data_len  = skb->data_len;
	n->len	     = skb->len;

	if (skb_shinfo(skb)->nr_frags) {
		int i;

		if (skb_orphan_frags(skb, gfp_mask)) {
			kfree_skb(n);
			n = NULL;
			goto out;
		}
		for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
			skb_shinfo(n)->frags[i] = skb_shinfo(skb)->frags[i];
			skb_frag_ref(skb, i);
		}
		skb_shinfo(n)->nr_frags = i;
	}

	if (skb_has_frag_list(skb)) {
		skb_shinfo(n)->frag_list = skb_shinfo(skb)->frag_list;
		skb_clone_fraglist(n);
	}

	copy_skb_header(n, skb);
out:
	return n;
}
Contributors
Person
Tokens
Prop
Commits
CommitProp
Linus Torvalds
167
63.74%
1
5.88%
Octavian Purdila
21
8.02%
1
5.88%
Eric Dumazet
20
7.63%
2
11.76%
Shirley Ma
17
6.49%
1
5.88%
Arnaldo Carvalho de Melo
12
4.58%
3
17.65%
Herbert Xu
8
3.05%
1
5.88%
Dan Carpenter
5
1.91%
1
5.88%
Mel Gorman
4
1.53%
1
5.88%
Ian Campbell
3
1.15%
1
5.88%
Linus Torvalds (pre-git)
2
0.76%
2
11.76%
Al Viro
1
0.38%
1
5.88%
David S. Miller
1
0.38%
1
5.88%
Michael S. Tsirkin
1
0.38%
1
5.88%
Total
262
100.00%
17
100.00%


EXPORT_SYMBOL(__pskb_copy_fclone);

/**
 *      pskb_expand_head - reallocate header of &sk_buff
 *      @skb: buffer to reallocate
 *      @nhead: room to add at head
 *      @ntail: room to add at tail
 *      @gfp_mask: allocation priority
 *
 *      Expands (or creates identical copy, if @nhead and @ntail are zero)
 *      header of @skb. &sk_buff itself is not changed. &sk_buff MUST have
 *      reference count of 1. Returns zero in the case of success or error,
 *      if expansion failed. In the last case, &sk_buff is not changed.
 *
 *      All the pointers pointing into skb header may change and must be
 *      reloaded after call to this function.
 */



int pskb_expand_head(struct sk_buff *skb, int nhead, int ntail,
		     gfp_t gfp_mask)
{
	int i, osize = skb_end_offset(skb);
	int size = osize + nhead + ntail;
	long off;
	u8 *data;

	BUG_ON(nhead < 0);

	if (skb_shared(skb))
		BUG();

	size = SKB_DATA_ALIGN(size);

	if (skb_pfmemalloc(skb))
		gfp_mask |= __GFP_MEMALLOC;
	data = kmalloc_reserve(size + SKB_DATA_ALIGN(sizeof(struct skb_shared_info)),
			       gfp_mask, NUMA_NO_NODE, NULL);
	if (!data)
		goto nodata;
	size = SKB_WITH_OVERHEAD(ksize(data));

	/* Copy only real data... and, alas, header. This should be
         * optimized for the cases when header is void.
         */
	memcpy(data + nhead, skb->head, skb_tail_pointer(skb) - skb->head);

	memcpy((struct skb_shared_info *)(data + size),
	       skb_shinfo(skb),
	       offsetof(struct skb_shared_info, frags[skb_shinfo(skb)->nr_frags]));

	/*
         * if shinfo is shared we must drop the old head gracefully, but if it
         * is not we can just drop the old head and let the existing refcount
         * be since all we did is relocate the values
         */
	if (skb_cloned(skb)) {
		/* copy this zero copy skb frags */
		if (skb_orphan_frags(skb, gfp_mask))
			goto nofrags;
		for (i = 0; i < skb_shinfo(skb)->nr_frags; i++)
			skb_frag_ref(skb, i);

		if (skb_has_frag_list(skb))
			skb_clone_fraglist(skb);

		skb_release_data(skb);
	} else {
		skb_free_head(skb);
	}
	off = (data + nhead) - skb->head;

	skb->head     = data;
	skb->head_frag = 0;
	skb->data    += off;
#ifdef NET_SKBUFF_DATA_USES_OFFSET
	skb->end      = size;
	off           = nhead;
#else
	skb->end      = skb->head + size;
#endif
	skb->tail	      += off;
	skb_headers_offset_update(skb, nhead);
	skb->cloned   = 0;
	skb->hdr_len  = 0;
	skb->nohdr    = 0;
	atomic_set(&skb_shinfo(skb)->dataref, 1);

	/* It is not generally safe to change skb->truesize.
         * For the moment, we really care of rx path, or
         * when skb is orphaned (not attached to a socket).
         */
	if (!skb->sk || skb->destructor == sock_edemux)
		skb->truesize += size - osize;

	return 0;

nofrags:
	kfree(data);
nodata:
	return -ENOMEM;
}
Contributors
Person
Tokens
Prop
Commits
CommitProp
Linus Torvalds
192
49.48%
1
3.70%
Eric Dumazet
85
21.91%
6
22.22%
Arnaldo Carvalho de Melo
21
5.41%
2
7.41%
Shirley Ma
19
4.90%
1
3.70%
Mel Gorman
16
4.12%
1
3.70%
Herbert Xu
15
3.87%
3
11.11%
Alexander Duyck
12
3.09%
2
7.41%
Patrick McHardy
12
3.09%
2
7.41%
Mikael Pettersson
4
1.03%
1
3.70%
Pravin B Shelar
3
0.77%
1
3.70%
Ian Campbell
2
0.52%
1
3.70%
Stephen Hemminger
2
0.52%
1
3.70%
Joseph Gasparakis
1
0.26%
1
3.70%
Weiping Pan (潘卫平)
1
0.26%
1
3.70%
Al Viro
1
0.26%
1
3.70%
Michael S. Tsirkin
1
0.26%
1
3.70%
David S. Miller
1
0.26%
1
3.70%
Total
388
100.00%
27
100.00%


EXPORT_SYMBOL(pskb_expand_head);

/* Make private copy of skb with writable head and some headroom */



struct sk_buff *skb_realloc_headroom(struct sk_buff *skb, unsigned int headroom)
{
	struct sk_buff *skb2;
	int delta = headroom - skb_headroom(skb);

	if (delta <= 0)
		skb2 = pskb_copy(skb, GFP_ATOMIC);
	else {
		skb2 = skb_clone(skb, GFP_ATOMIC);
		if (skb2 && pskb_expand_head(skb2, SKB_DATA_ALIGN(delta), 0,
					     GFP_ATOMIC)) {
			kfree_skb(skb2);
			skb2 = NULL;
		}
	}
	return skb2;
}
Contributors
Person
Tokens
Prop
Commits
CommitProp
Linus Torvalds
75
83.33%
1
33.33%
Arnaldo Carvalho de Melo
14
15.56%
1
33.33%
Mikael Pettersson
1
1.11%
1
33.33%
Total
90
100.00%
3
100.00%


EXPORT_SYMBOL(skb_realloc_headroom);

/**
 *      skb_copy_expand -       copy and expand sk_buff
 *      @skb: buffer to copy
 *      @newheadroom: new free bytes at head
 *      @newtailroom: new free bytes at tail
 *      @gfp_mask: allocation priority
 *
 *      Make a copy of both an &sk_buff and its data and while doing so
 *      allocate additional space.
 *
 *      This is used when the caller wishes to modify the data and needs a
 *      private copy of the data to alter as well as more space for new fields.
 *      Returns %NULL on failure or the pointer to the buffer
 *      on success. The returned buffer has a reference count of 1.
 *
 *      You must pass %GFP_ATOMIC as the allocation priority if this function
 *      is called from an interrupt.
 */


struct sk_buff *skb_copy_expand(const struct sk_buff *skb,
				int newheadroom, int newtailroom,
				gfp_t gfp_mask)
{
	/*
         *      Allocate the copy buffer
         */
	struct sk_buff *n = __alloc_skb(newheadroom + skb->len + newtailroom,
					gfp_mask, skb_alloc_rx_flag(skb),
					NUMA_NO_NODE);
	int oldheadroom = skb_headroom(skb);
	int head_copy_len, head_copy_off;

	if (!n)
		return NULL;

	skb_reserve(n, newheadroom);

	/* Set the tail pointer and length */
	skb_put(n, skb->len);

	head_copy_len = oldheadroom;
	head_copy_off = 0;
	if (newheadroom <= head_copy_len)
		head_copy_len = newheadroom;
	else
		head_copy_off = newheadroom - head_copy_len;

	/* Copy the linear header and data. */
	if (skb_copy_bits(skb, -head_copy_len, n->head + head_copy_off,
			  skb->len + head_copy_len))
		BUG();

	copy_skb_header(n, skb);

	skb_headers_offset_update(n, newheadroom - oldheadroom);

	return n;
}
Contributors
Person
Tokens
Prop
Commits
CommitProp
Linus Torvalds
88
56.41%
1
9.09%
David S. Miller
31
19.87%
1
9.09%
Patrick McHardy
15
9.62%
2
18.18%
Mel Gorman
8
5.13%
1
9.09%
Arnaldo Carvalho de Melo
4
2.56%
1
9.09%
Pravin B Shelar
3
1.92%
1
9.09%
Eric Dumazet
3
1.92%
1
9.09%
Joseph Gasparakis
2
1.28%
1
9.09%
Al Viro
1
0.64%
1
9.09%
Stephen Hemminger
1
0.64%
1
9.09%
Total
156
100.00%
11
100.00%


EXPORT_SYMBOL(skb_copy_expand);

/**
 *      skb_pad                 -       zero pad the tail of an skb
 *      @skb: buffer to pad
 *      @pad: space to pad
 *
 *      Ensure that a buffer is followed by a padding area that is zero
 *      filled. Used by network drivers which may DMA or transfer data
 *      beyond the buffer end onto the wire.
 *
 *      May return error in out of memory cases. The skb is freed on error.
 */



int skb_pad(struct sk_buff *skb, int pad)
{
	int err;
	int ntail;

	/* If the skbuff is non linear tailroom is always zero.. */
	if (!skb_cloned(skb) && skb_tailroom(skb) >= pad) {
		memset(skb->data+skb->len, 0, pad);
		return 0;
	}

	ntail = skb->data_len + pad - (skb->end - skb->tail);
	if (likely(skb_cloned(skb) || ntail > 0)) {
		err = pskb_expand_head(skb, 0, ntail, GFP_ATOMIC);
		if (unlikely(err))
			goto free_skb;
	}

	/* FIXME: The use of this function with non-linear skb's really needs
         * to be audited.
         */
	err = skb_linearize(skb);
	if (unlikely(err))
		goto free_skb;

	memset(skb->data + skb->len, 0, pad);
	return 0;

free_skb:
	kfree_skb(skb);
	return err;
}
Contributors
Person
Tokens
Prop
Commits
CommitProp
Herbert Xu
81
51.27%
1
33.33%
Alan Cox
75
47.47%
1
33.33%
Arnaldo Carvalho de Melo
2
1.27%
1
33.33%
Total
158
100.00%
3
100.00%


EXPORT_SYMBOL(skb_pad);

/**
 *      pskb_put - add data to the tail of a potentially fragmented buffer
 *      @skb: start of the buffer to use
 *      @tail: tail fragment of the buffer to use
 *      @len: amount of data to add
 *
 *      This function extends the used data area of the potentially
 *      fragmented buffer. @tail must be the last fragment of @skb -- or
 *      @skb itself. If this would exceed the total buffer size the kernel
 *      will panic. A pointer to the first byte of the extra data is
 *      returned.
 */



unsigned char *pskb_put(struct sk_buff *skb, struct sk_buff *tail, int len)
{
	if (tail != skb) {
		skb->data_len += len;
		skb->len += len;
	}
	return skb_put(tail, len);
}
Contributors
Person
Tokens
Prop
Commits
CommitProp
Mathias Krause
48
100.00%
1
100.00%
Total
48
100.00%
1
100.00%


EXPORT_SYMBOL_GPL(pskb_put);

/**
 *      skb_put - add data to a buffer
 *      @skb: buffer to use
 *      @len: amount of data to add
 *
 *      This function extends the used data area of the buffer. If this would
 *      exceed the total buffer size the kernel will panic. A pointer to the
 *      first byte of the extra data is returned.
 */


unsigned char *skb_put(struct sk_buff *skb, unsigned int len)
{
	unsigned char *tmp = skb_tail_pointer(skb);
	SKB_LINEAR_ASSERT(skb);
	skb->tail += len;
	skb->len  += len;
	if (unlikely(skb->tail > skb->end))
		skb_over_panic(skb, len, __builtin_return_address(0));
	return tmp;
}
Contributors
Person
Tokens
Prop
Commits
CommitProp
Ilpo Järvinen
71
100.00%
1
100.00%
Total
71
100.00%
1
100.00%


EXPORT_SYMBOL(skb_put);

/**
 *      skb_push - add data to the start of a buffer
 *      @skb: buffer to use
 *      @len: amount of data to add
 *
 *      This function extends the used data area of the buffer at the buffer
 *      start. If this would exceed the total buffer headroom the kernel will
 *      panic. A pointer to the first byte of the extra data is returned.
 */


unsigned char *skb_push(struct sk_buff *skb, unsigned int len)
{
	skb->data -= len;
	skb->len  += len;
	if (unlikely(skb->data<skb->head))
		skb_under_panic(skb, len, __builtin_return_address(0));
	return skb->data;
}
Contributors
Person
Tokens
Prop
Commits
CommitProp
Ilpo Järvinen
58
100.00%
1
100.00%
Total
58
100.00%
1
100.00%


EXPORT_SYMBOL(skb_push);

/**
 *      skb_pull - remove data from the start of a buffer
 *      @skb: buffer to use
 *      @len: amount of data to remove
 *
 *      This function removes data from the start of a buffer, returning
 *      the memory to the headroom. A pointer to the next data in the buffer
 *      is returned. Once the data has been pulled future pushes will overwrite
 *      the old data.
 */


unsigned char *skb_pull(struct sk_buff *skb, unsigned int len)
{
	return skb_pull_inline(skb, len);
}
Contributors
Person
Tokens
Prop
Commits
CommitProp
Ilpo Järvinen
23
95.83%
1
50.00%
David S. Miller
1
4.17%
1
50.00%
Total
24
100.00%
2
100.00%


EXPORT_SYMBOL(skb_pull);

/**
 *      skb_trim - remove end from a buffer
 *      @skb: buffer to alter
 *      @len: new length
 *
 *      Cut the length of a buffer down by removing data from the tail. If
 *      the buffer is already under the length specified it is not modified.
 *      The skb must be linear.
 */


void skb_trim(struct sk_buff *skb, unsigned int len)
{
	if (skb->len > len)
		__skb_trim(skb, len);
}
Contributors
Person
Tokens
Prop
Commits
CommitProp
Ilpo Järvinen
29
100.00%
1
100.00%
Total
29
100.00%
1
100.00%


EXPORT_SYMBOL(skb_trim);

/* Trims skb to length len. It can change skb pointers.
 */



int ___pskb_trim(struct sk_buff *skb, unsigned int len)
{
	struct sk_buff **fragp;
	struct sk_buff *frag;
	int offset = skb_headlen(skb);
	int nfrags = skb_shinfo(skb)->nr_frags;
	int i;
	int err;

	if (skb_cloned(skb) &&
	    unlikely((err = pskb_expand_head(skb, 0, 0, GFP_ATOMIC))))
		return err;

	i = 0;
	if (offset >= len)
		goto drop_pages;

	for (; i < nfrags; i++) {
		int end = offset + skb_frag_size(&skb_shinfo(skb)->frags[i]);

		if (end < len) {
			offset = end;
			continue;
		}

		skb_frag_size_set(&skb_shinfo(skb)->frags[i++], len - offset);

drop_pages:
		skb_shinfo(skb)->nr_frags = i;

		for (; i < nfrags; i++)
			skb_frag_unref(skb, i);

		if (skb_has_frag_list(skb))
			skb_drop_fraglist(skb);
		goto done;
	}

	for (fragp = &skb_shinfo(skb)->frag_list; (frag = *fragp);
	     fragp = &frag->next) {
		int end = offset + frag->len;

		if (skb_shared(frag)) {
			struct sk_buff *nfrag;

			nfrag = skb_clone(frag, GFP_ATOMIC);
			if (unlikely(!nfrag))
				return -ENOMEM;

			nfrag->next = frag->next;
			consume_skb(frag);
			frag = nfrag;
			*fragp = frag;
		}

		if (end < len) {
			offset = end;
			continue;
		}

		if (end > len &&
		    unlikely((err = pskb_trim(frag, len - offset))))
			return err;

		if (frag->next)
			skb_drop_list(&frag->next);
		break;
	}

done:
	if (len > skb_headlen(skb)) {
		skb->data_len -= skb->len - len;
		skb->len       = len;
	} else {
		skb->len       = len;
		skb->data_len  = 0;
		skb_set_tail_pointer(skb, len);
	}

	if (!skb->sk || skb->destructor == sock_edemux)
		skb_condense(skb);
	return 0;
}
Contributors
Person
Tokens
Prop
Commits
CommitProp
Herbert Xu
238
57.35%
2
22.22%
Linus Torvalds
142
34.22%
1
11.11%
Eric Dumazet
28
6.75%
3
33.33%
Arnaldo Carvalho de Melo
4
0.96%
1
11.11%
Ian Campbell
2
0.48%
1
11.11%
David S. Miller
1
0.24%
1
11.11%
Total
415
100.00%
9
100.00%


EXPORT_SYMBOL(___pskb_trim);

/**
 *      __pskb_pull_tail - advance tail of skb header
 *      @skb: buffer to reallocate
 *      @delta: number of bytes to advance tail
 *
 *      The function makes a sense only on a fragmented &sk_buff,
 *      it expands header moving its tail forward and copying necessary
 *      data from fragmented part.
 *
 *      &sk_buff MUST have reference count of 1.
 *
 *      Returns %NULL (and &sk_buff does not change) if pull failed
 *      or value of new tail of skb in the case of success.
 *
 *      All the pointers pointing into skb header may change and must be
 *      reloaded after call to this function.
 */

/* Moves tail of skb head forward, copying data from fragmented part,
 * when it is necessary.
 * 1. It may fail due to malloc failure.
 * 2. It may change skb pointers.
 *
 * It is pretty complicated. Luckily, it is called only in exceptional cases.
 */


unsigned char *__pskb_pull_tail(struct sk_buff *skb, int delta)
{
	/* If skb has not enough free space at tail, get new one
         * plus 128 bytes for future expansions. If we have enough
         * room at tail, reallocate without expansion only if skb is cloned.
         */
	int i, k, eat = (skb->tail + delta) - skb->end;

	if (eat > 0 || skb_cloned(skb)) {
		if (pskb_expand_head(skb, 0, eat > 0 ? eat + 128 : 0,
				     GFP_ATOMIC))
			return NULL;
	}

	if (skb_copy_bits(skb, skb_headlen(skb), skb_tail_pointer(skb), delta))
		BUG();

	/* Optimization: no fragments, no reasons to preestimate
         * size of pulled pages. Superb.
         */
	if (!skb_has_frag_list(skb))
		goto pull_pages;

	/* Estimate size of pulled pages. */
	eat = delta;
	for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
		int size = skb_frag_size(&skb_shinfo(skb)->frags[i]);

		if (size >= eat)
			goto pull_pages;
		eat -= size;
	}

	/* If we need update frag list, we are in troubles.
         * Certainly, it possible to add an offset to skb data,
         * but taking into account that pulling is expected to
         * be very rare operation, it is worth to fight against
         * further bloating skb head and crucify ourselves here instead.
         * Pure masohism, indeed. 8)8)
         */
	if (eat) {
		struct sk_buff *list = skb_shinfo(skb)->frag_list;
		struct sk_buff *clone = NULL;
		struct sk_buff *insp = NULL;

		do {
			BUG_ON(!list);

			if (list->len <= eat) {
				/* Eaten as whole. */
				eat -= list->len;
				list = list->next;
				insp = list;
			} else {
				/* Eaten partially. */

				if (skb_shared(list)) {
					/* Sucks! We need to fork list. :-( */
					clone = skb_clone(list, GFP_ATOMIC);
					if (!clone)
						return NULL;
					insp = list->next;
					list = clone;
				} else {
					/* This may be pulled without
                                         * problems. */
					insp = list;
				}
				if (!pskb_pull(list, eat)) {
					kfree_skb(clone);
					return NULL;
				}
				break;
			}
		} while (eat);

		/* Free pulled out fragments. */
		while ((list = skb_shinfo(skb)->frag_list) != insp) {
			skb_shinfo(skb)->frag_list = list->next;
			kfree_skb(list);
		}
		/* And insert new clone at head. */
		if (clone) {
			clone->next = list;
			skb_shinfo(skb)->frag_list = clone;
		}
	}
	/* Success! Now we may commit changes to skb data. */

pull_pages:
	eat = delta;
	k = 0;
	for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
		int size = skb_frag_size(&skb_shinfo(skb)->frags[i]);

		if (size <= eat) {
			skb_frag_unref(skb, i);
			eat -= size;
		} else {
			skb_shinfo(skb)->frags[k] = skb_shinfo(skb)->frags[i];
			if (eat) {
				skb_shinfo(skb)->frags[k].page_offset += eat;
				skb_frag_size_sub(&skb_shinfo(skb)->frags[k], eat);
				eat = 0;
			}
			k++;
		}
	}
	skb_shinfo(skb)->nr_frags = k;

	skb->tail     += delta;
	skb->data_len -= delta;

	return skb_tail_pointer(skb);
}
Contributors
Person
Tokens
Prop
Commits
CommitProp
Linus Torvalds
475
91.17%
1
12.50%
Eric Dumazet
25
4.80%
1
12.50%
Arnaldo Carvalho de Melo
15
2.88%
3
37.50%
Kris Katterjohn
3
0.58%
1
12.50%
Ian Campbell
2
0.38%
1
12.50%
David S. Miller
1
0.19%
1
12.50%
Total
521
100.00%
8
100.00%


EXPORT_SYMBOL(__pskb_pull_tail);

/**
 *      skb_copy_bits - copy bits from skb to kernel buffer
 *      @skb: source skb
 *      @offset: offset in source
 *      @to: destination buffer
 *      @len: number of bytes to copy
 *
 *      Copy the specified number of bytes from the source skb to the
 *      destination buffer.
 *
 *      CAUTION ! :
 *              If its prototype is ever changed,
 *              check arch/{*}/net/{*}.S files,
 *              since it is called from BPF assembly code.
 */


int skb_copy_bits(const struct sk_buff *skb, int offset, void *to, int len)
{
	int start = skb_headlen(skb);
	struct sk_buff *frag_iter;
	int i, copy;

	if (offset > (int)skb->len - len)
		goto fault;

	/* Copy header. */
	if ((copy = start - offset) > 0) {
		if (copy > len)
			copy = len;
		skb_copy_from_linear_data_offset(skb, offset, to, copy);
		if ((len -= copy) == 0)
			return 0;
		offset += copy;
		to     += copy;
	}

	for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
		int end;
		skb_frag_t *f = &skb_shinfo(skb)->frags[i];

		WARN_ON(start > offset + len);

		end = start + skb_frag_size(f);
		if ((copy = end - offset) > 0) {
			u8 *vaddr;

			if (copy > len)
				copy = len;

			vaddr = kmap_atomic(skb_frag_page(f));
			memcpy(to,
			       vaddr + f->page_offset + offset - start,
			       copy);
			kunmap_atomic(vaddr);

			if ((len -= copy) == 0)
				return 0;
			offset += copy;
			to     += copy;
		}
		start = end;
	}

	skb_walk_frags(skb, frag_iter) {
		int end;

		WARN_ON(start > offset + len);

		end = start + frag_iter->len;
		if ((copy = end - offset) > 0) {
			if (copy > len)
				copy = len;
			if (skb_copy_bits(frag_iter, offset - start, to, copy))
				goto fault;
			if ((len -= copy) == 0)
				return 0;
			offset += copy;
			to     += copy;
		}
		start = end;
	}

	if (!len)
		return 0;

fault:
	return -EFAULT;
}
Contributors
Person
Tokens
Prop
Commits
CommitProp
Linus Torvalds
279
77.07%
1
11.11%
David S. Miller
47
12.98%
2
22.22%
Eric Dumazet
24
6.63%
2
22.22%
Arnaldo Carvalho de Melo
5
1.38%
2
22.22%
Ilpo Järvinen
4
1.10%
1
11.11%
James Morris
3
0.83%
1
11.11%
Total
362
100.00%
9
100.00%


EXPORT_SYMBOL(skb_copy_bits);

/*
 * Callback from splice_to_pipe(), if we need to release some pages
 * at the end of the spd in case we error'ed out in filling the pipe.
 */


static void sock_spd_release(struct splice_pipe_desc *spd, unsigned int i)
{
	put_page(spd->pages[i]);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Jens Axboe
19
76.00%
1
50.00%
Jarek Poplawski
6
24.00%
1
50.00%
Total
25
100.00%
2
100.00%



static struct page *linear_to_page(struct page *page, unsigned int *len,
				   unsigned int *offset,
				   struct sock *sk)
{
	struct page_frag *pfrag = sk_page_frag(sk);

	if (!sk_page_frag_refill(sk, pfrag))
		return NULL;

	*len = min_t(unsigned int, *len, pfrag->size - pfrag->offset);

	memcpy(page_address(pfrag->page) + pfrag->offset,
	       page_address(page) + *offset, *len);
	*offset = pfrag->offset;
	pfrag->offset += *len;

	return pfrag->page;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Jarek Poplawski
79
73.83%
3
60.00%
Eric Dumazet
26
24.30%
1
20.00%
Jens Axboe
2
1.87%
1
20.00%
Total
107
100.00%
5
100.00%



static bool spd_can_coalesce(const struct splice_pipe_desc *spd,
			     struct page *page,
			     unsigned int offset)
{
	return	spd->nr_pages &&
		spd->pages[spd->nr_pages - 1] == page &&
		(spd->partial[spd->nr_pages - 1].offset +
		 spd->partial[spd->nr_pages - 1].len == offset);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Eric Dumazet
69
100.00%
1
100.00%
Total
69
100.00%
1
100.00%

/*
 * Fill page/offset/length into spd, if it can hold more pages.
 */


static bool spd_fill_page(struct splice_pipe_desc *spd,
			  struct pipe_inode_info *pipe, struct page *page,
			  unsigned int *len, unsigned int offset,
			  bool linear,
			  struct sock *sk)
{
	if (unlikely(spd->nr_pages == MAX_SKB_FRAGS))
		return true;

	if (linear) {
		page = linear_to_page(page, len, &offset, sk);
		if (!page)
			return true;
	}
	if (spd_can_coalesce(spd, page, offset)) {
		spd->partial[spd->nr_pages - 1].len += *len;
		return false;
	}
	get_page(page);
	spd->pages[spd->nr_pages] = page;
	spd->partial[spd->nr_pages].len = *len;
	spd->partial[spd->nr_pages].offset = offset;
	spd->nr_pages++;

	return false;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Jens Axboe
85
52.15%
2
25.00%
Jarek Poplawski
40
24.54%
3
37.50%
Eric Dumazet
33
20.25%
2
25.00%
David S. Miller
5
3.07%
1
12.50%
Total
163
100.00%
8
100.00%



static bool __splice_segment(struct page *page, unsigned int poff,
			     unsigned int plen, unsigned int *off,
			     unsigned int *len,
			     struct splice_pipe_desc *spd, bool linear,
			     struct sock *sk,
			     struct pipe_inode_info *pipe)
{
	if (!*len)
		return true;

	/* skip this segment if already processed */
	if (*off >= plen) {
		*off -= plen;
		return false;
	}

	/* ignore any bits we already processed */
	poff += *off;
	plen -= *off;
	*off = 0;

	do {
		unsigned int flen = min(*len, plen);

		if (spd_fill_page(spd, pipe, page, &flen, poff,
				  linear, sk))
			return true;
		poff += flen;
		plen -= flen;
		*len -= flen;
	} while (*len && plen);

	return false;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Octavian Purdila
82
53.95%
1
10.00%
Eric Dumazet
28
18.42%
3
30.00%
Jens Axboe
26
17.11%
2
20.00%
Jarek Poplawski
11
7.24%
3
30.00%
David S. Miller
5
3.29%
1
10.00%
Total
152
100.00%
10
100.00%

/*
 * Map linear and fragment data from the skb to spd. It reports true if the
 * pipe is full or if we already spliced the requested length.
 */


static bool __skb_splice_bits(struct sk_buff *skb, struct pipe_inode_info *pipe,
			      unsigned int *offset, unsigned int *len,
			      struct splice_pipe_desc *spd, struct sock *sk)
{
	int seg;
	struct sk_buff *iter;

	/* map the linear part :
         * If skb->head_frag is set, this 'linear' part is backed by a
         * fragment, and if the head is not shared with any clones then
         * we can avoid a copy since we own the head portion of this page.
         */
	if (__splice_segment(virt_to_page(skb->data),
			     (unsigned long) skb->data & (PAGE_SIZE - 1),
			     skb_headlen(skb),
			     offset, len, spd,
			     skb_head_is_locked(skb),
			     sk, pipe))
		return true;

	/*
         * then map the fragments
         */
	for (seg = 0; seg < skb_shinfo(skb)->nr_frags; seg++) {
		const skb_frag_t *f = &skb_shinfo(skb)->frags[seg];

		if (__splice_segment(skb_frag_page(f),
				     f->page_offset, skb_frag_size(f),
				     offset, len, spd, false, sk, pipe))
			return true;
	}

	skb_walk_frags(skb, iter) {
		if (*offset >= iter->len) {
			*offset -= iter->len;
			continue;
		}
		/* __skb_splice_bits() only fails if the output has no room
                 * left, so no point in going over the frag_list for the error
                 * case.
                 */
		if (__skb_splice_bits(iter, pipe, offset, len, spd, sk))
			return true;
	}

	return false;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Jens Axboe
73
33.80%
2
15.38%
Octavian Purdila
62
28.70%
1
7.69%
Tom Herbert
53
24.54%
1
7.69%
Jarek Poplawski
11
5.09%
2
15.38%
Alexander Duyck
5
2.31%
2
15.38%
Eric Dumazet
4
1.85%
2
15.38%
David S. Miller
4
1.85%
1
7.69%
Ian Campbell
3
1.39%
1
7.69%
Harvey Harrison
1
0.46%
1
7.69%
Total
216
100.00%
13
100.00%

/*
 * Map data from the skb to a pipe. Should handle both the linear part,
 * the fragments, and the frag list.
 */


int skb_splice_bits(struct sk_buff *skb, struct sock *sk, unsigned int offset,
		    struct pipe_inode_info *pipe, unsigned int tlen,
		    unsigned int flags)
{
	struct partial_page partial[MAX_SKB_FRAGS];
	struct page *pages[MAX_SKB_FRAGS];
	struct splice_pipe_desc spd = {
		.pages = pages,
		.partial = partial,
		.nr_pages_max = MAX_SKB_FRAGS,
		.flags = flags,
		.ops = &nosteal_pipe_buf_ops,
		.spd_release = sock_spd_release,
        };
	int ret = 0;

	__skb_splice_bits(skb, pipe, &offset, &tlen, &spd, sk);

	if (spd.nr_pages)
		ret = splice_to_pipe(pipe, &spd);

	return ret;
}
Contributors
Person
Tokens
Prop
Commits
CommitProp
Jens Axboe
108
85.71%
2
20.00%
Eric Dumazet
7
5.56%
2
20.00%
Hannes Frederic Sowa
5
3.97%
1
10.00%
Jarek Poplawski
3
2.38%
2
20.00%
Miklos Szeredi
1
0.79%
1
10.00%
Tom Herbert
1
0.79%
1
10.00%
Al Viro
1
0.79%
1
10.00%
Total
126
100.00%
10
100.00%


EXPORT_SYMBOL_GPL(skb_splice_bits);

/**
 *      skb_store_bits - store bits from kernel buffer to skb
 *      @skb: destination buffer
 *      @offset: offset in destination
 *      @from: source buffer
 *      @len: number of bytes to copy
 *
 *      Copy the specified number of bytes from the source buffer to the
 *      destination skb.  This function handles all the messy bits of
 *      traversing fragment lists and such.
 */



int skb_store_bits(struct sk_buff *skb, int offset, const void *from, int len)
{
	int start = skb_headlen(skb);
	struct sk_buff *frag_iter;
	int i, copy;

	if (offset > (int)skb->len - len)
		goto fault;

	if ((copy = start - offset) > 0) {
		if (copy > len)
			copy = len;
		skb_copy_to_linear_data_offset(skb, offset, from, copy);
		if ((len -= copy) == 0)
			return 0;
		offset += copy;
		from += copy;
	}

	for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
		skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
		int end;

		WARN_ON(start > offset + len);

		end = start + skb_frag_size(frag);
		if ((copy = end - offset) > 0) {
			u8 *vaddr;

			if (copy > len)
				copy = len;

			vaddr = kmap_atomic(skb_frag_page(frag));
			memcpy(vaddr + frag->page_offset + offset - start,
			       from, copy);
			kunmap_atomic(vaddr);

			if ((len -= copy) == 0)
				return 0;
			offset += copy;
			from += copy;
		}
		start = end;
	}

	skb_walk_frags(skb, frag_iter) {
		int end;

		WARN_ON(start > offset + len);

		end = start + frag_iter->len;
		if ((copy = end - offset) > 0) {
			if (copy > len)
				copy = len;
			if (skb_store_bits(frag_iter, offset - start,
					   from, copy))
				goto fault;
			if ((len -= copy) == 0)
				return 0;
			offset += copy;
			from += copy;
		}
		start = end;
	}
	if (!len)
		return 0;

fault:
	return -EFAULT;
}
Contributors
Person
Tokens
Prop
Commits
CommitProp
Herbert Xu
299
82.83%
1
12.50%
David S. Miller
47
13.02%
2
25.00%
Eric Dumazet
8
2.22%
2
25.00%
Ilpo Järvinen
4
1.11%
1
12.50%
Arnaldo Carvalho de Melo
2
0.55%
1
12.50%
Stephen Hemminger
1
0.28%
1
12.50%
Total
361
100.00%
8
100.00%


EXPORT_SYMBOL(skb_store_bits);

/* Checksum skb data. */


__wsum __skb_checksum(const struct sk_buff *skb, int offset, int len,
		      __wsum csum, const struct skb_checksum_ops *ops)
{
	int start = skb_headlen(skb);
	int i, copy = start - offset;
	struct sk_buff *frag_iter;
	int pos = 0;

	/* Checksum header. */
	if (copy > 0) {
		if (copy > len)
			copy = len;
		csum = ops->update(skb->data + offset, copy, csum);
		if ((len -= copy) == 0)
			return csum;
		offset += copy;
		pos	= copy;
	}

	for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
		int end;
		skb_frag_t *frag = &skb_shinfo(skb)->frags[i];

		WARN_ON(start > offset + len);

		end = start + skb_frag_size(frag);
		if ((copy = end - offset) > 0) {
			__wsum csum2;
			u8 *vaddr;

			if (copy > len)
				copy = len;
			vaddr = kmap_atomic(skb_frag_page(frag));
			csum2 = ops->update(vaddr + frag->page_offset +
					    offset - start, copy, 0);
			kunmap_atomic(vaddr);
			csum = ops->combine(csum, csum2, pos, copy);
			if (!(len -= copy))
				return csum;
			offset += copy;
			pos    += copy;
		}
		start = end;
	}

	skb_walk_frags(skb, frag_iter) {
		int end;

		WARN_ON(start > offset + len);

		end = start + frag_iter->len;
		if ((copy = end - offset) > 0) {
			__wsum csum2;
			if (copy > len)
				copy = len;
			csum2 = __skb_checksum(frag_iter, offset - start,
					       copy, 0, ops);
			csum = ops->combine(csum, csum2, pos, copy);
			if ((len -= copy) == 0)
				return csum;
			offset += copy;
			pos    += copy;
		}
		start = end;
	}
	BUG_ON(len);

	return csum;
}
Contributors
Person
Tokens
Prop
Commits
CommitProp
Linus Torvalds
278
70.92%
1
7.69%
David S. Miller
42
10.71%
2
15.38%
Daniel Borkmann
26
6.63%
1
7.69%
Eric Dumazet
24
6.12%
2
15.38%
Arnaldo Carvalho de Melo
8
2.04%
1
7.69%
Al Viro
4
1.02%
3
23.08%
Ilpo Järvinen
4
1.02%
1
7.69%
James Morris
3
0.77%
1
7.69%
Kris Katterjohn
3
0.77%
1
7.69%
Total
392
100.00%
13
100.00%


EXPORT_SYMBOL(__skb_checksum);



__wsum skb_checksum(const struct sk_buff *skb, int offset,
		    int len, __wsum csum)
{
	const struct skb_checksum_ops ops = {
		.update  = csum_partial_ext,
		.combine = csum_block_add_ext,
        };

	return __skb_checksum(skb, offset, len, csum, &ops);
}
Contributors
Person
Tokens
Prop
Commits
CommitProp
Daniel Borkmann
52
100.00%
2
100.00%
Total
52
100.00%
2
100.00%


EXPORT_SYMBOL(skb_checksum);

/* Both of above in one bottle. */



__wsum skb_copy_and_csum_bits(const struct sk_buff *skb, int offset,
				    u8 *to, int len, __wsum csum)
{
	int start = skb_headlen(skb);
	int i, copy = start - offset;
	struct sk_buff *frag_iter;
	int pos = 0;

	/* Copy header. */
	if (copy > 0) {
		if (copy > len)
			copy = len;
		csum = csum_partial_copy_nocheck(skb->data + offset, to,
						 copy, csum);
		if ((len -= copy) == 0)
			return csum;
		offset += copy;
		to     += copy;
		pos	= copy;
	}

	for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
		int end;

		WARN_ON(start > offset + len);

		end = start + skb_frag_size(&skb_shinfo(skb)->frags[i]);
		if ((copy = end - offset) > 0) {
			__wsum csum2;
			u8 *vaddr;
			skb_frag_t *frag = &skb_shinfo(skb)->frags[i];

			if (copy > len)
				copy = len;
			vaddr = kmap_atomic(skb_frag_page(frag));
			csum2 = csum_partial_copy_nocheck(vaddr +
							  frag->page_offset +
							  offset - start, to,
							  copy, 0);
			kunmap_atomic(vaddr);
			csum = csum_block_add(csum, csum2, pos);
			if (!(len -= copy))
				return csum;
			offset += copy;
			to     += copy;
			pos    += copy;
		}
		start = end;
	}

	skb_walk_frags(skb, frag_iter) {
		__wsum csum2;
		int end;

		WARN_ON(start > offset + len);

		end = start + frag_iter->len;
		if ((copy = end - offset) > 0) {
			if (copy > len)
				copy = len;
			csum2 = skb_copy_and_csum_bits(frag_iter,
						       offset - start,
						       to, copy, 0);
			csum = csum_block_add(csum, csum2, pos);
			if ((len -= copy) == 0)
				return csum;
			offset += copy;
			to     += copy;
			pos    += copy;
		}
		start = end;
	}
	BUG_ON(len);
	return csum;
}
Contributors
Person
Tokens
Prop
Commits
CommitProp
Linus Torvalds
328
81.39%
1
7.69%
David S. Miller
42
10.42%
2
15.38%
Eric Dumazet
9
2.23%
2
15.38%
Arnaldo Carvalho de Melo
8
1.99%
1
7.69%
Ilpo Järvinen
4
0.99%
1
7.69%
Al Viro
4
0.99%
2
15.38%
James Morris
3
0.74%
1
7.69%
Kris Katterjohn
3
0.74%
1
7.69%
Linus Torvalds (pre-git)
2
0.50%
2
15.38%
Total
403
100.00%
13
100.00%


EXPORT_SYMBOL(skb_copy_and_csum_bits);

 /**
 *      skb_zerocopy_headlen - Calculate headroom needed for skb_zerocopy()
 *      @from: source buffer
 *
 *      Calculates the amount of linear headroom needed in the 'to' skb passed
 *      into skb_zerocopy().
 */

unsigned int

skb_zerocopy_headlen(const struct sk_buff *from)
{
	unsigned int hlen = 0;

	if (!from->head_frag ||
	    skb_headlen(from) < L1_CACHE_BYTES ||
	    skb_shinfo(from)->nr_frags >= MAX_SKB_FRAGS)
		hlen = skb_headlen(from);

	if (skb_has_frag_list(from))
		hlen = from->len;

	return hlen;
}
Contributors
Person
Tokens
Prop
Commits
CommitProp
Thomas Graf
36
56.25%
1
25.00%
Linus Torvalds
25
39.06%
1
25.00%
James Morris
2
3.12%
1
25.00%
Kris Katterjohn
1
1.56%
1
25.00%
Total
64
100.00%
4
100.00%


EXPORT_SYMBOL_GPL(skb_zerocopy_headlen);

/**
 *      skb_zerocopy - Zero copy skb to skb
 *      @to: destination buffer
 *      @from: source buffer
 *      @len: number of bytes to copy from source buffer
 *      @hlen: size of linear headroom in destination buffer
 *
 *      Copies up to `len` bytes from `from` to `to` by creating references
 *      to the frags in the source buffer.
 *
 *      The `hlen` as calculated by skb_zerocopy_headlen() specifies the
 *      headroom in the `to` buffer.
 *
 *      Return value:
 *      0: everything is OK
 *      -ENOMEM: couldn't orphan frags of @from due to lack of memory
 *      -EFAULT: skb_copy_bits() found some problem with skb geometry
 */

int

skb_zerocopy(struct sk_buff *to, struct sk_buff *from, int len, int hlen)
{
	int i, j = 0;
	int plen = 0; /* length of skb->head fragment */
	int ret;
	struct page *page;
	unsigned int offset;

	BUG_ON(!from->head_frag && !hlen);

	/* dont bother with small payloads */
	if (len <= skb_tailroom(to))
		return skb_copy_bits(from, 0, skb_put(to, len), len);

	if (hlen) {
		ret = skb_copy_bits(from, 0, skb_put(to, hlen), hlen);
		if (unlikely(ret))
			return ret;
		len -= hlen;
	} else {
		plen = min_t(int, skb_headlen(from), len);
		if (plen) {
			page = virt_to_head_page(from->head);
			offset = from->data - (unsigned char *)page_address(page);
			__skb_fill_page_desc(to, 0, page, offset, plen);
			get_page(page);
			j = 1;
			len -= plen;
		}
	}

	to->truesize += len + plen;
	to->len += len + plen;
	to->data_len += len + plen;

	if (unlikely(skb_orphan_frags(from, GFP_ATOMIC))) {
		skb_tx_error(from);
		return -ENOMEM;
	}

	for (i = 0; i < skb_shinfo(from)->nr_frags; i++) {
		if (!len)
			break;
		skb_shinfo(to)->frags[j] = skb_shinfo(from)->frags[i];
		skb_shinfo(to)->frags[j].size = min_t(int, skb_shinfo(to)->frags[j].size, len);
		len -= skb_shinfo(to)->frags[j].size;
		skb_frag_ref(to, j);
		j++;
	}
	skb_shinfo(to)->nr_frags = j;

	return 0;
}
Contributors
Person
Tokens
Prop
Commits
CommitProp
Thomas Graf
232
65.17%
1
25.00%
Stephen Hemminger
69
19.38%
1
25.00%
Zoltan Kiss
44
12.36%
1
25.00%
David S. Miller
11
3.09%
1
25.00%
Total
356
100.00%
4
100.00%


EXPORT_SYMBOL_GPL(skb_zerocopy);



void skb_copy_and_csum_dev(const struct sk_buff *skb, u8 *to)
{
	__wsum csum;
	long csstart;

	if (skb->ip_summed == CHECKSUM_PARTIAL)
		csstart = skb_checksum_start_offset(skb);
	else
		csstart = skb_headlen(skb);

	BUG_ON(csstart > skb_headlen(skb));

	skb_copy_from_linear_data(skb, to, csstart);

	csum = 0;
	if (csstart != skb->len)
		csum = skb_copy_and_csum_bits(skb, csstart, to + csstart,
					      skb->len - csstart, 0);

	if (skb->ip_summed == CHECKSUM_PARTIAL) {
		long csstuff = csstart + skb->csum_offset;

		*((__sum16 *)(to + csstuff)) = csum_fold(csum);
	}
}
Contributors
Person
Tokens
Prop
Commits
CommitProp
Linus Torvalds
74
55.64%
1
8.33%
Arnaldo Carvalho de Melo
34
25.56%
3
25.00%
Stephen Hemminger
13
9.77%
1
8.33%
Al Viro
3
2.26%
2
16.67%
David S. Miller
2
1.50%
1
8.33%
Kris Katterjohn
2
1.50%
1
8.33%
James Morris
2
1.50%
1
8.33%
Patrick McHardy
2
1.50%
1
8.33%
Michał Mirosław
1
0.75%
1
8.33%
Total
133
100.00%
12
100.00%


EXPORT_SYMBOL(skb_copy_and_csum_dev);

/**
 *      skb_dequeue - remove from the head of the queue
 *      @list: list to dequeue from
 *
 *      Remove the head of the list. The list lock is taken so the function
 *      may be used safely with other locking list functions. The head item is
 *      returned or %NULL if the list is empty.
 */



struct sk_buff *skb_dequeue(struct sk_buff_head *list)
{
	unsigned long flags;
	struct sk_buff *result;

	spin_lock_irqsave(&list->lock, flags);
	result = __skb_dequeue(list);
	spin_unlock_irqrestore(&list->lock, flags);
	return result;
}
Contributors
Person
Tokens
Prop
Commits
CommitProp
Stephen Hemminger
31
60.78%
1
25.00%
Arnaldo Carvalho de Melo
17
33.33%
1
25.00%
Eric Dumazet
2
3.92%
1
25.00%
Ian Campbell
1
1.96%
1
25.00%
Total
51
100.00%
4
100.00%


EXPORT_SYMBOL(skb_dequeue);

/**
 *      skb_dequeue_tail - remove from the tail of the queue
 *      @list: list to dequeue from
 *
 *      Remove the tail of the list. The list lock is taken so the function
 *      may be used safely with other locking list functions. The tail item is
 *      returned or %NULL if the list is empty.
 */


struct sk_buff *skb_dequeue_tail(struct sk_buff_head *list)
{
	unsigned long flags;
	struct sk_buff *result;

	spin_lock_irqsave(&list->lock, flags);
	result = __skb_dequeue_tail(list);
	spin_unlock_irqrestore(&list->lock, flags);
	return result;
}
Contributors
Person
Tokens
Prop
Commits
CommitProp
Stephen Hemminger
37
72.55%
1
33.33%
Arnaldo Carvalho de Melo
9
17.65%
1
33.33%
Eric Dumazet
5
9.80%
1
33.33%
Total
51
100.00%
3
100.00%


EXPORT_SYMBOL(skb_dequeue_tail);

/**
 *      skb_queue_purge - empty a list
 *      @list: list to empty
 *
 *      Delete all buffers on an &sk_buff list. Each buffer is removed from
 *      the list and one reference dropped. This function takes the list
 *      lock and is atomic with respect to other list locking functions.
 */


void skb_queue_purge(struct sk_buff_head *list)
{
	struct sk_buff *skb;
	while ((skb = skb_dequeue(list)) != NULL)
		kfree_skb(skb);
}
Contributors
Person
Tokens
Prop
Commits
CommitProp
Stephen Hemminger
18
54.55%
1
25.00%
Arnaldo Carvalho de Melo
9
27.27%
1
25.00%
Eric Dumazet
5
15.15%
1
25.00%
Américo Wang
1
3.03%
1
25.00%
Total
33
100.00%
4
100.00%


EXPORT_SYMBOL(skb_queue_purge);

/**
 *      skb_rbtree_purge - empty a skb rbtree
 *      @root: root of the rbtree to empty
 *
 *      Delete all buffers on an &sk_buff rbtree. Each buffer is removed from
 *      the list and one reference dropped. This function does not take
 *      any lock. Synchronization should be handled by the caller (e.g., TCP
 *      out-of-order queue is protected by the socket lock).
 */


void skb_rbtree_purge(struct rb_root *root)
{
	struct sk_buff *skb, *next;

	rbtree_postorder_for_each_entry_safe(skb, next, root, rbnode)
		kfree_skb(skb);

	*root = RB_ROOT;
}

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Yaogong Wang
38
100.00%
1
100.00%
Total
38
100.00%
1
100.00%

/**
 *      skb_queue_head - queue a buffer at the list head
 *      @list: list to use
 *      @newsk: buffer to queue
 *
 *      Queue a buffer at the start of the list. This function takes the
 *      list lock and can be used safely with other locking &sk_buff functions
 *      safely.
 *
 *      A buffer cannot be placed on two lists at the same time.
 */


void skb_queue_head(struct sk_buff_head *list, struct sk_buff *newsk)
{
	unsigned long flags;

	spin_lock_irqsave(&list->lock, flags);
	__skb_queue_head(list, newsk);
	spin_unlock_irqrestore(&list->lock, flags);
}
Contributors
Person
Tokens
Prop
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CommitProp
Stephen Hemminger
39
84.78%
1
50.00%
Arnaldo Carvalho de Melo
7
15.22%
1
50.00%
Total
46
100.00%
2
100.00%


EXPORT_SYMBOL(skb_queue_head);

/**
 *      skb_queue_tail - queue a buffer at the list tail
 *      @list: list to use
 *      @newsk: buffer to queue
 *
 *      Queue a buffer at the tail of the list. This function takes the
 *      list lock and can be used safely with other locking &sk_buff functions
 *      safely.
 *
 *      A buffer cannot be placed on two lists at the same time.
 */


void skb_queue_tail(struct sk_buff_head *list, struct sk_buff *newsk)
{
	unsigned long flags;

	spin_lock_irqsave(&list->lock, flags);
	__skb_queue_tail(list, newsk);
	spin_unlock_irqrestore(&list->lock, flags);
}
Contributors
Person
Tokens
Prop
Commits
CommitProp
Stephen Hemminger
33
71.74%
1
33.33%
Ilpo Järvinen
13
28.26%
2
66.67%
Total
46
100.00%
3
100.00%


EXPORT_SYMBOL(skb_queue_tail);

/**
 *      skb_unlink      -       remove a buffer from a list
 *      @skb: buffer to remove
 *      @list: list to use
 *
 *      Remove a packet from a list. The list locks are taken and this
 *      function is atomic with respect to other list locked calls
 *
 *      You must know what list the SKB is on.
 */


void skb_unlink(struct sk_buff *skb, struct sk_buff_head *list)
{
	unsigned long flags;

	spin_lock_irqsave(&list->lock, flags);
	__skb_unlink(skb, list);
	spin_unlock_irqrestore(&list->lock, flags);
}
Contributors
Person
Tokens
Prop
Commits
CommitProp
Ilpo Järvinen
25
54.35%
1
50.00%
Stephen Hemminger
21
45.65%
1
50.00%
Total
46
100.00%
2
100.00%


EXPORT_SYMBOL(skb_unlink);

/**
 *      skb_append      -       append a buffer
 *      @old: buffer to insert after
 *      @newsk: buffer to insert
 *      @list: list to use
 *
 *      Place a packet after a given packet in a list. The list locks are taken
 *      and this function is atomic with respect to other list locked calls.
 *      A buffer cannot be placed on two lists at the same time.
 */


void skb_append(struct sk_buff *old, struct sk_buff *newsk, struct sk_buff_head *list)
{
	unsigned long flags;

	spin_lock_irqsave(&list->lock, flags);
	__skb_queue_after(list, old, newsk);
	spin_unlock_irqrestore(&list->lock, flags);
}
Contributors
Person
Tokens
Prop
Commits
CommitProp
Stephen Hemminger
37
69.81%
1
20.00%
Ilpo Järvinen
8
15.09%
2
40.00%
David S. Miller
5
9.43%
1
20.00%
Gerrit Renker
3
5.66%
1
20.00%
Total
53
100.00%
5
100.00%


EXPORT_SYMBOL(skb_append);

/**
 *      skb_insert      -       insert a buffer
 *      @old: buffer to insert before
 *      @newsk: buffer to insert
 *      @list: list to use
 *
 *      Place a packet before a given packet in a list. The list locks are
 *      taken and this function is atomic with respect to other list locked
 *      calls.
 *
 *      A buffer cannot be placed on two lists at the same time.
 */


void skb_insert(struct sk_buff *old, struct sk_buff *newsk, struct sk_buff_head *list)
{
	unsigned long flags;

	spin_lock_irqsave(&list->lock, flags);
	__skb_insert(newsk, old->prev, old, list);
	spin_unlock_irqrestore(&list->lock, flags);
}
Contributors
Person
Tokens
Prop
Commits
CommitProp
Stephen Hemminger
41
71.93%
1
25.00%
Eric Dumazet
6
10.53%
1
25.00%
Ilpo Järvinen
5
8.77%
1
25.00%
David S. Miller
5
8.77%
1
25.00%
Total
57
100.00%
4
100.00%


EXPORT_SYMBOL(skb_insert);



static inline void skb_split_inside_header(struct sk_buff *skb,
					   struct sk_buff* skb1,
					   const u32 len, const int pos)
{
	int i;

	skb_copy_from_linear_data_offset(skb, len, skb_put(skb1, pos - len),
					 pos - len);
	/* And move data appendix as is. */
	for (i = 0; i < skb_shinfo(skb)->nr_frags; i++)
		skb_shinfo(skb1)->frags[i] = skb_shinfo(skb)->frags[i];

	skb_shinfo(skb1)->nr_frags = skb_shinfo(skb)->nr_frags;
	skb_shinfo(skb)->nr_frags  = 0;
	skb1->data_len		   = skb->data_len;
	skb1->len		   += skb1->data_len;
	skb->data_len		   = 0;
	skb->len		   = len;
	skb_set_tail_pointer(skb, len);
}

Contributors
Person
Tokens
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Commits
CommitProp
Arnaldo Carvalho de Melo
90
62.07%
3
50.00%
Ilpo Järvinen
47
32.41%
1
16.67%
Eric Dumazet
7
4.83%
1
16.67%
Jesper Juhl
1
0.69%
1
16.67%
Total
145
100.00%
6
100.00%



static inline void skb_split_no_header(struct sk_buff *skb,
				       struct sk_buff* skb1,
				       const u32 len, int pos)
{
	int i, k = 0;
	const int nfrags = skb_shinfo(skb)->nr_frags;

	skb_shinfo(skb)->nr_frags = 0;
	skb1->len		  = skb1->data_len = skb->len - len;
	skb->len		  = len;
	skb->data_len		  = len - pos;

	for (i = 0; i < nfrags; i++) {
		int size = skb_frag_size(&skb_shinfo(skb)->frags[i]);

		if (pos + size > len) {
			skb_shinfo(skb1)->frags[k] = skb_shinfo(skb)->frags[i];

			if (pos < len) {
				/* Split frag.
                                 * We have two variants in this case:
                                 * 1. Move all the frag to the second
                                 *    part, if it is possible. F.e.
                                 *    this approach is mandatory for TUX,
                                 *    where splitting is expensive.
                                 * 2. Split is accurately. We make this.
                                 */
				skb_frag_ref(skb, i);
				skb_shinfo(skb1)->frags[0].page_offset += len - pos;
				skb_frag_size_sub(&skb_shinfo(skb1)->frags[0], len - pos);
				skb_frag_size_set(&skb_shinfo(skb)->frags[i], len - pos);
				skb_shinfo(skb)->nr_frags++;
			}
			k++;
		} else
			skb_shinfo(skb)->nr_frags++;
		pos += size;
	}
	skb_shinfo(skb1)->nr_frags = k;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Arnaldo Carvalho de Melo
155
64.05%
1
16.67%
Ilpo Järvinen
70
28.93%
1
16.67%
Eric Dumazet
13
5.37%
1
16.67%
Ian Campbell
2
0.83%
1
16.67%
Martin Waitz
1
0.41%
1
16.67%
Jesper Juhl
1
0.41%
1
16.67%
Total
242
100.00%
6
100.00%

/**
 * skb_split - Split fragmented skb to two parts at length len.
 * @skb: the buffer to split
 * @skb1: the buffer to receive the second part
 * @len: new length for skb
 */


void skb_split(struct sk_buff *skb, struct sk_buff *skb1, const u32 len)
{
	int pos = skb_headlen(skb);

	skb_shinfo(skb1)->tx_flags = skb_shinfo(skb)->tx_flags & SKBTX_SHARED_FRAG;
	if (len < pos)	/* Split line is inside header. */
		skb_split_inside_header(skb, skb1, len, pos);
	else		/* Second chunk has no header, nothing to copy. */
		skb_split_no_header(skb, skb1, len, pos);
}
Contributors
Person
Tokens
Prop
Commits
CommitProp
Arnaldo Carvalho de Melo
43
58.11%
1
20.00%
Thomas Graf
19
25.68%
1
20.00%
Eric Dumazet
6
8.11%
1
20.00%
Pravin B Shelar
4
5.41%
1
20.00%
Américo Wang
2
2.70%
1
20.00%
Total
74
100.00%
5
100.00%


EXPORT_SYMBOL(skb_split);

/* Shifting from/to a cloned skb is a no-go.
 *
 * Caller cannot keep skb_shinfo related pointers past calling here!
 */


static int skb_prepare_for_shift(struct sk_buff *skb)
{
	return skb_cloned(skb) && pskb_expand_head(skb, 0, 0, GFP_ATOMIC);
}

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Ilpo Järvinen
25
89.29%
2
66.67%
Thomas Graf
3
10.71%
1
33.33%
Total
28
100.00%
3
100.00%

/**
 * skb_shift - Shifts paged data partially from skb to another
 * @tgt: buffer into which tail data gets added
 * @skb: buffer from which the paged data comes from
 * @shiftlen: shift up to this many bytes
 *
 * Attempts to shift up to shiftlen worth of bytes, which may be less than
 * the length of the skb, from skb to tgt. Returns number bytes shifted.
 * It's up to caller to free skb if everything was shifted.
 *
 * If @tgt runs out of frags, the whole operation is aborted.
 *
 * Skb cannot include anything else but paged data while tgt is allowed
 * to have non-paged data as well.
 *
 * TODO: full sized shift could be optimized but that would need
 * specialized skb free'er to handle frags without up-to-date nr_frags.
 */


int skb_shift(struct sk_buff *tgt, struct sk_buff *skb, int shiftlen)
{
	int from, to, merge, todo;
	struct skb_frag_struct *fragfrom, *fragto;

	BUG_ON(shiftlen > skb->len);

	if (skb_headlen(skb))
		return 0;

	todo = shiftlen;
	from = 0;
	to = skb_shinfo(tgt)->nr_frags;
	fragfrom = &skb_shinfo(skb)->frags[from];

	/* Actual merge is delayed until the point when we know we can
         * commit all, so that we don't have to undo partial changes
         */
	if (!to ||
	    !skb_can_coalesce(tgt, to, skb_frag_page(fragfrom),
			      fragfrom->page_offset)) {
		merge = -1;
	} else {
		merge = to - 1;

		todo -= skb_frag_size(fragfrom);
		if (todo < 0) {
			if (skb_prepare_for_shift(skb) ||
			    skb_prepare_for_shift(tgt))
				return 0;

			/* All previous frag pointers might be stale! */
			fragfrom = &skb_shinfo(skb)->frags[from];
			fragto = &skb_shinfo(tgt)->frags[merge];

			skb_frag_size_add(fragto, shiftlen);
			skb_frag_size_sub(fragfrom, shiftlen);
			fragfrom->page_offset += shiftlen;

			goto onlymerged;
		}

		from++;
	}

	/* Skip full, not-fitting skb to avoid expensive operations */
	if ((shiftlen == skb->len) &&
	    (skb_shinfo(skb)->nr_frags - from) > (MAX_SKB_FRAGS - to))
		return 0;

	if (skb_prepare_for_shift(skb) || skb_prepare_for_shift(tgt))
		return 0;

	while ((todo > 0) && (from < skb_shinfo(skb)->nr_frags)) {
		if (to == MAX_SKB_FRAGS)
			return 0;

		fragfrom = &skb_shinfo(skb)->frags[from];
		fragto = &skb_shinfo(tgt)->frags[to];

		if (todo >= skb_frag_size(fragfrom)) {
			*fragto = *fragfrom;
			todo -= skb_frag_size(fragfrom);
			from++;
			to++;

		} else {
			__skb_frag_ref(fragfrom);
			fragto->page = fragfrom->page;
			fragto->page_offset = fragfrom->page_offset;
			skb_frag_size_set(fragto, todo);

			fragfrom->page_offset += todo;
			skb_frag_size_sub(fragfrom, todo);
			todo = 0;

			to++;
			break;
		}
	}

	/* Ready to "commit" this state change to tgt */
	skb_shinfo(tgt)->nr_frags = to;

	if (merge >= 0) {
		fragfrom = &skb_shinfo(skb)->frags[0];
		fragto = &skb_shinfo(tgt)->frags[merge];

		skb_frag_size_add(fragto, skb_frag_size(fragfrom));
		__skb_frag_unref(fragfrom);
	}

	/* Reposition in the original skb */
	to = 0;
	while (from < skb_shinfo(skb)->nr_frags)
		skb_shinfo(skb)->frags[to++] = skb_shinfo(skb)->frags[from++];
	skb_shinfo(skb)->nr_frags = to;

	BUG_ON(todo > 0 && !skb_shinfo(skb)->nr_frags);

onlymerged:
	/* Most likely the tgt won't ever need its checksum anymore, skb on
         * the other hand might need it if it needs to be resent
         */
	tgt->ip_summed = CHECKSUM_PARTIAL;
	skb->ip_summed = CHECKSUM_PARTIAL;

	/* Yak, is it really working this way? Some helper please? */
	skb->len -= shiftlen;
	skb->data_len -= shiftlen;
	skb->truesize -= shiftlen;
	tgt->len += shiftlen;
	tgt->data_len += shiftlen;
	tgt->truesize += shiftlen;

	return shiftlen;
}

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Ilpo Järvinen
419
74.03%
2
14.29%
Thomas Graf
86
15.19%
2
14.29%
Eric Dumazet
32
5.65%
3
21.43%
David S. Miller
6
1.06%
1
7.14%
Herbert Xu
5
0.88%
1
7.14%
Ian Campbell
5
0.88%
1
7.14%
Olaf Kirch
5
0.88%
1
7.14%
Shyam Iyer
4
0.71%
1
7.14%
Wedson Almeida Filho
2
0.35%
1
7.14%
Thomas Chenault
2
0.35%
1
7.14%
Total
566
100.00%
14
100.00%

/**
 * skb_prepare_seq_read - Prepare a sequential read of skb data
 * @skb: the buffer to read
 * @from: lower offset of data to be read
 * @to: upper offset of data to be read
 * @st: state variable
 *
 * Initializes the specified state variable. Must be called before
 * invoking skb_seq_read() for the first time.
 */


void skb_prepare_seq_read(struct sk_buff *skb, unsigned int from,
			  unsigned int to, struct skb_seq_state *st)
{
	st->lower_offset = from;
	st->upper_offset = to;
	st->root_skb = st->cur_skb = skb;
	st->frag_idx = st->stepped_offset = 0;
	st->frag_data = NULL;
}
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EXPORT_SYMBOL(skb_prepare_seq_read);

/**
 * skb_seq_read - Sequentially read skb data
 * @consumed: number of bytes consumed by the caller so far
 * @data: destination pointer for data to be returned
 * @st: state variable
 *
 * Reads a block of skb data at @consumed relative to the
 * lower offset specified to skb_prepare_seq_read(). Assigns
 * the head of the data block to @data and returns the length
 * of the block or 0 if the end of the skb data or the upper
 * offset has been reached.
 *
 * The caller is not required to consume all of the data
 * returned, i.e. @consumed is typically set to the number
 * of bytes already consumed and the next call to
 * skb_seq_read() will return the remaining part of the block.
 *
 * Note 1: The size of each block of data returned can be arbitrary,
 *       this limitation is the cost for zerocopy sequential
 *       reads of potentially non linear data.
 *
 * Note 2: Fragment lists within fragments are not implemented
 *       at the moment, state->root_skb could be replaced with
 *       a stack for this purpose.
 */


unsigned int skb_seq_read(unsigned int consumed, const u8 **data,
			  struct skb_seq_state *st)
{
	unsigned int block_limit, abs_offset = consumed + st->lower_offset;
	skb_frag_t *frag;

	if (unlikely(abs_offset >= st->upper_offset)) {
		if (st->frag_data) {
			kunmap_atomic(st->frag_data);
			st->frag_data = NULL;
		}
		return 0;
	}

next_skb:
	block_limit = skb_headlen(st->cur_skb) + st->stepped_offset;

	if (abs_offset < block_limit && !st->frag_data) {
		*data = st->cur_skb->data + (abs_offset - st->stepped_offset);
		return block_limit - abs_offset;
	}

	if (st->frag_idx == 0 && !st->frag_data)
		st->stepped_offset += skb_headlen(st->cur_skb);

	while (st->frag_idx < skb_shinfo(st->cur_skb)->nr_frags) {
		frag = &skb_shinfo(st->cur_skb)->frags[st->frag_idx];
		block_limit = skb_frag_size(frag) + st->stepped_offset;

		if (abs_offset < block_limit) {
			if (!st->frag_data)
				st->frag_data = kmap_atomic(skb_frag_page(frag));

			*data = (u8 *) st->frag_data + frag->page_offset +
				(abs_offset - st->stepped_offset);

			return block_limit - abs_offset;
		}

		if (st->frag_data) {
			kunmap_atomic(st->frag_data);
			st->frag_data = NULL;
		}

		st->frag_idx++;
		st->stepped_offset += skb_frag_size(frag);
	}

	if (st->frag_data) {
		kunmap_atomic(st->frag_data);
		st->frag_data = NULL;
	}

	if (st->root_skb == st->cur_skb && skb_has_frag_list(st->root_skb)) {
		st->cur_skb = skb_shinfo(st->root_skb)->frag_list;
		st->frag_idx = 0;
		goto next_skb;
	} else if (st->cur_skb->next) {
		st->cur_skb = st->cur_skb->next;
		st->frag_idx = 0;
		goto next_skb;
	}

	return 0;
}
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285
75.40%
1
11.11%
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23
6.08%
1
11.11%
Olaf Kirch
20
5.29%
1
11.11%
Shyam Iyer
17
4.50%
1
11.11%
Herbert Xu
15
3.97%
1
11.11%
Eric Dumazet
12
3.17%
2
22.22%
Thomas Chenault
5
1.32%
1
11.11%
David S. Miller
1
0.26%
1
11.11%
Total
378
100.00%
9
100.00%


EXPORT_SYMBOL(skb_seq_read);

/**
 * skb_abort_seq_read - Abort a sequential read of skb data
 * @st: state variable
 *
 * Must be called if skb_seq_read() was not called until it
 * returned 0.
 */


void skb_abort_seq_read(struct skb_seq_state *st)
{
	if (st->frag_data)
		kunmap_atomic(st->frag_data);
}
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1
4.35%
1
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Total
23
100.00%
2
100.00%


EXPORT_SYMBOL(skb_abort_seq_read);


#define TS_SKB_CB(state)	((struct skb_seq_state *) &((state)->cb))



static unsigned int skb_ts_get_next_block(unsigned int offset, const u8 **text,
					  struct ts_config *conf,
					  struct ts_state *state)
{
	return skb_seq_read(offset, text, TS_SKB_CB(state));
}

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40
100.00%
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100.00%



static void skb_ts_finish(struct ts_config *conf, struct ts_state *state)
{
	skb_abort_seq_read(TS_SKB_CB(state));
}

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24
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100.00%

/**
 * skb_find_text - Find a text pattern in skb data
 * @skb: the buffer to look in
 * @from: search offset
 * @to: search limit
 * @config: textsearch configuration
 *
 * Finds a pattern in the skb data according to the specified
 * textsearch configuration. Use textsearch_next() to retrieve
 * subsequent occurrences of the pattern. Returns the offset
 * to the first occurrence or UINT_MAX if no match was found.
 */


unsigned int skb_find_text(struct sk_buff *skb, unsigned int from,
			   unsigned int to, struct ts_config *config)
{
	struct ts_state state;
	unsigned int ret;

	config->get_next_block = skb_ts_get_next_block;
	config->finish = skb_ts_finish;

	skb_prepare_seq_read(skb, from, to, TS_SKB_CB(&state));

	ret = textsearch_find(config, &state);
	return (ret <= to - from ? ret : UINT_MAX);
}
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Thomas Graf
58
70.73%
1
33.33%
Phil Oester
19
23.17%
1
33.33%
Bojan Prtvar
5
6.10%
1
33.33%
Total
82
100.00%
3
100.00%


EXPORT_SYMBOL(skb_find_text);

/**
 * skb_append_datato_frags - append the user data to a skb
 * @sk: sock  structure
 * @skb: skb structure to be appended with user data.
 * @getfrag: call back function to be used for getting the user data
 * @from: pointer to user message iov
 * @length: length of the iov message
 *
 * Description: This procedure append the user data in the fragment part
 * of the skb if any page alloc fails user this procedure returns  -ENOMEM
 */


int skb_append_datato_frags(struct sock *sk, struct sk_buff *skb,
			int (*getfrag)(void *from, char *to, int offset,
					int len, int odd, struct sk_buff *skb),
			void *from, int length)
{
	int frg_cnt = skb_shinfo(skb)->nr_frags;
	int copy;
	int offset = 0;
	int ret;
	struct page_frag *pfrag = &current->task_frag;

	do {
		/* Return error if we don't have space for new frag */
		if (frg_cnt >= MAX_SKB_FRAGS)
			return -EMSGSIZE;

		if (!sk_page_frag_refill(sk, pfrag))
			return -ENOMEM;

		/* copy the user data to page */
		copy = min_t(int, length, pfrag->size - pfrag->offset);

		ret = getfrag(from, page_address(pfrag->page) + pfrag->offset,
			      offset, copy, 0, skb);
		if (ret < 0)
			return -EFAULT;

		/* copy was successful so update the size parameters */
		skb_fill_page_desc(skb, frg_cnt, pfrag->page, pfrag->offset,
				   copy);
		frg_cnt++;
		pfrag->offset += copy;
		get_page(pfrag->page);

		skb->truesize += copy;
		atomic_add(copy, &sk->sk_wmem_alloc);
		skb->len += copy;
		skb->data_len += copy;
		offset += copy;
		length -= copy;

	} while (length > 0);

	return 0;
}
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Ananda Raju
152
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1
20.00%
Eric Dumazet
86
35.25%
2
40.00%
Martin Waitz
3
1.23%
1
20.00%
Thomas Graf
3
1.23%
1
20.00%
Total
244
100.00%
5
100.00%


EXPORT_SYMBOL(skb_append_datato_frags);



int skb_append_pagefrags(struct sk_buff *skb, struct page *page,
			 int offset, size_t size)
{
	int i = skb_shinfo(skb)->nr_frags;

	if (skb_can_coalesce(skb, i, page, offset)) {
		skb_frag_size_add(&skb_shinfo(skb)->frags[i - 1], size);
	} else if (i < MAX_SKB_FRAGS) {
		get_page(page);
		skb_fill_page_desc(skb, i, page, offset, size);
	} else {
		return -EMSGSIZE;
	}

	return 0;
}
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101
100.00%
1
100.00%


EXPORT_SYMBOL_GPL(skb_append_pagefrags);

/**
 *      skb_pull_rcsum - pull skb and update receive checksum
 *      @skb: buffer to update
 *      @len: length of data pulled
 *
 *      This function performs an skb_pull on the packet and updates
 *      the CHECKSUM_COMPLETE checksum.  It should be used on
 *      receive path processing instead of skb_pull unless you know
 *      that the checksum difference is zero (e.g., a valid IP header)
 *      or you are setting ip_summed to CHECKSUM_NONE.
 */


unsigned char *skb_pull_rcsum(struct sk_buff *skb, unsigned int len)
{
	unsigned char *data = skb->data;

	BUG_ON(len > skb->len);
	__skb_pull(skb, len);
	skb_postpull_rcsum(skb, data, len);
	return skb->data;
}
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20
36.36%
1
25.00%
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11
20.00%
1
25.00%
Phil Oester
2
3.64%
1
25.00%
Total
55
100.00%
4
100.00%


EXPORT_SYMBOL_GPL(skb_pull_rcsum);

/**
 *      skb_segment - Perform protocol segmentation on skb.
 *      @head_skb: buffer to segment
 *      @features: features for the output path (see dev->features)
 *
 *      This function performs segmentation on the given skb.  It returns
 *      a pointer to the first in a list of new skbs for the segments.
 *      In case of error it returns ERR_PTR(err).
 */


struct sk_buff *skb_segment(struct sk_buff *head_skb,
			    netdev_features_t features)
{
	struct sk_buff *segs = NULL;
	struct sk_buff *tail = NULL;
	struct sk_buff *list_skb = skb_shinfo(head_skb)->frag_list;
	skb_frag_t *frag = skb_shinfo(head_skb)->frags;
	unsigned int mss = skb_shinfo(head_skb)->gso_size;
	unsigned int doffset = head_skb->data - skb_mac_header(head_skb);
	struct sk_buff *frag_skb = head_skb;
	unsigned int offset = doffset;
	unsigned int tnl_hlen = skb_tnl_header_len(head_skb);
	unsigned int partial_segs = 0;
	unsigned int headroom;
	unsigned int len = head_skb->len;
	__be16 proto;
	bool csum, sg;
	int nfrags = skb_shinfo(head_skb)->nr_frags;
	int err = -ENOMEM;
	int i = 0;
	int pos;
	int dummy;

	__skb_push(head_skb, doffset);
	proto = skb_network_protocol(head_skb, &dummy);
	if (unlikely(!proto))
		return ERR_PTR(-EINVAL);

	sg = !!(features & NETIF_F_SG);
	csum = !!can_checksum_protocol(features, proto);

	if (sg && csum && (mss != GSO_BY_FRAGS))  {
		if (!(features & NETIF_F_GSO_PARTIAL)) {
			struct sk_buff *iter;
			unsigned int frag_len;

			if (!list_skb ||
			    !net_gso_ok(features, skb_shinfo(head_skb)->gso_type))
				goto normal;

			/* If we get here then all the required
                         * GSO features except frag_list are supported.
                         * Try to split the SKB to multiple GSO SKBs
                         * with no frag_list.
                         * Currently we can do that only when the buffers don't
                         * have a linear part and all the buffers except
                         * the last are of the same length.
                         */
			frag_len = list_skb->len;
			skb_walk_frags(head_skb, iter) {
				if (frag_len != iter->len && iter->next)
					goto normal;
				if (skb_headlen(iter))
					goto normal;

				len -= iter->len;
			}

			if (len != frag_len)
				goto normal;
		}

		/* GSO partial only requires that we trim off any excess that
                 * doesn't fit into an MSS sized block, so take care of that
                 * now.
                 */
		partial_segs = len / mss;
		if (partial_segs > 1)
			mss *= partial_segs;
		else
			partial_segs = 0;
	}

normal:
	headroom = skb_headroom(head_skb);
	pos = skb_headlen(head_skb);

	do {
		struct sk_buff *nskb;
		skb_frag_t *nskb_frag;
		int hsize;
		int size;

		if (unlikely(mss == GSO_BY_FRAGS)) {
			len = list_skb->len;
		} else {
			len = head_skb->len - offset;
			if (len > mss)
				len = mss;
		}

		hsize = skb_headlen(head_skb) - offset;
		if (hsize < 0)
			hsize = 0;
		if (hsize > len || !sg)
			hsize = len;

		if (!hsize && i >= nfrags && skb_headlen(list_skb) &&
		    (skb_headlen(list_skb) == len || sg)) {
			BUG_ON(skb_headlen(list_skb) > len);

			i = 0;
			nfrags = skb_shinfo(list_skb)->nr_frags;
			frag = skb_shinfo(list_skb)->frags;
			frag_skb = list_skb;
			pos += skb_headlen(list_skb);

			while (pos < offset + len) {
				BUG_ON(i >= nfrags);

				size = skb_frag_size(frag);
				if (pos + size > offset + len)
					break;

				i++;
				pos += size;
				frag++;
			}

			nskb = skb_clone(list_skb, GFP_ATOMIC);
			list_skb = list_skb->next;

			if (unlikely(!nskb))
				goto err;

			if (unlikely(pskb_trim(nskb, len))) {
				kfree_skb(nskb);
				goto err;
			}

			hsize = skb_end_offset(nskb);
			if (skb_cow_head(nskb, doffset + headroom)) {
				kfree_skb(nskb);
				goto err;
			}

			nskb->truesize += skb_end_offset(nskb) - hsize;
			skb_release_head_state(nskb);
			__skb_push(nskb, doffset);
		} else {
			nskb = __alloc_skb(hsize + doffset + headroom,
					   GFP_ATOMIC, skb_alloc_rx_flag(head_skb),
					   NUMA_NO_NODE);

			if (unlikely(!nskb))
				goto err;

			skb_reserve(nskb, headroom);
			__skb_put(nskb, doffset);
		}

		if (segs)
			tail->next = nskb;
		else
			segs = nskb;
		tail = nskb;

		__copy_skb_header(nskb, head_skb);

		skb_headers_offset_update(nskb, skb_headroom(nskb) - headroom);
		skb_reset_mac_len(nskb);

		skb_copy_from_linear_data_offset(head_skb, -tnl_hlen,
						 nskb->data - tnl_hlen,
						 doffset + tnl_hlen);

		if (nskb->len == len + doffset)
			goto perform_csum_check;

		if (!sg) {
			if (!nskb->remcsum_offload)
				nskb->ip_summed = CHECKSUM_NONE;
			SKB_GSO_CB(nskb)->csum =
				skb_copy_and_csum_bits(head_skb, offset,
						       skb_put(nskb, len),
						       len, 0);
			SKB_GSO_CB(nskb)->csum_start =
				skb_headroom(nskb) + doffset;
			continue;
		}

		nskb_frag = skb_shinfo(nskb)->frags;

		skb_copy_from_linear_data_offset(head_skb, offset,
						 skb_put(nskb, hsize), hsize);

		skb_shinfo(nskb)->tx_flags = skb_shinfo(head_skb)->tx_flags &
			SKBTX_SHARED_FRAG;

		while (pos < offset + len) {
			if (i >= nfrags) {
				BUG_ON(skb_headlen(list_skb));

				i = 0;
				nfrags = skb_shinfo(list_skb)->nr_frags;
				frag = skb_shinfo(list_skb)->frags;
				frag_skb = list_skb;

				BUG_ON(!nfrags);

				list_skb = list_skb->next;
			}

			if (unlikely(skb_shinfo(nskb)->nr_frags >=
				     MAX_SKB_FRAGS)) {
				net_warn_ratelimited(
					"skb_segment: too many frags: %u %u\n",
					pos, mss);
				goto err;
			}

			if (unlikely(skb_orphan_frags(frag_skb, GFP_ATOMIC)))
				goto err;

			*nskb_frag = *frag;
			__skb_frag_ref(nskb_frag);
			size = skb_frag_size(nskb_frag);

			if (pos < offset) {
				nskb_frag->page_offset += offset - pos;
				skb_frag_size_sub(nskb_frag, offset - pos);
			}

			skb_shinfo(nskb)->nr_frags++;

			if (pos + size <= offset + len) {
				i++;
				frag++;
				pos += size;
			} else {
				skb_frag_size_sub(nskb_frag, pos + size - (offset + len));
				goto skip_fraglist;
			}

			nskb_frag++;
		}

skip_fraglist:
		nskb->data_len = len - hsize;
		nskb->len += nskb->data_len;
		nskb->truesize += nskb->data_len;

perform_csum_check:
		if (!csum) {
			if (skb_has_shared_frag(nskb)) {
				err = __skb_linearize(nskb);
				if (err)
					goto err;
			}
			if (!nskb->remcsum_offload)
				nskb->ip_summed = CHECKSUM_NONE;
			SKB_GSO_CB(nskb)->csum =
				skb_checksum(nskb, doffset,
					     nskb->len - doffset, 0);
			SKB_GSO_CB(nskb)->csum_start =
				skb_headroom(nskb) + doffset;
		}
	} while ((offset += len) < head_skb->len);

	/* Some callers want to get the end of the list.
         * Put it in segs->prev to avoid walking the list.
         * (see validate_xmit_skb_list() for example)
         */
	segs->prev = tail;

	if (partial_segs) {
		struct sk_buff *iter;
		int type = skb_shinfo(head_skb)->gso_type;
		unsigned short gso_size = skb_shinfo(head_skb)->gso_size;

		/* Update type to add partial and then remove dodgy if set */
		type |= (features & NETIF_F_GSO_PARTIAL) / NETIF_F_GSO_PARTIAL * SKB_GSO_PARTIAL;
		type &= ~SKB_GSO_DODGY;

		/* Update GSO info and prepare to start updating headers on
                 * our way back down the stack of protocols.
                 */
		for (iter = segs; iter; iter = iter->next) {
			skb_shinfo(iter)->gso_size = gso_size;
			skb_shinfo(iter)->gso_segs = partial_segs;
			skb_shinfo(iter)->gso_type = type;
			SKB_GSO_CB(iter)->data_offset = skb_headroom(iter) + doffset;
		}

		if (tail->len - doffset <= gso_size)
			skb_shinfo(tail)->gso_size = 0;
		else if (tail != segs)
			skb_shinfo(tail)->gso_segs = DIV_ROUND_UP(tail->len - doffset, gso_size);
	}

	/* Following permits correct backpressure, for protocols
         * using skb_set_owner_w().
         * Idea is to tranfert ownership from head_skb to last segment.
         */
	if (head_skb->destructor == sock_wfree) {
		swap(tail->truesize, head_skb->truesize);
		swap(tail->destructor, head_skb->destructor);
		swap(tail->sk, head_skb->sk);
	}
	return segs;

err:
	kfree_skb_list(segs);
	return ERR_PTR(err);
}
Contributors
Person
Tokens
Prop
Commits
CommitProp
Herbert Xu
664
46.76%
8
16.00%
Alexander Duyck
164
11.55%
7
14.00%
Steffen Klassert
153
10.77%
1
2.00%
Michael S. Tsirkin
81
5.70%
5
10.00%
Pravin B Shelar
79
5.56%
3
6.00%
Eric Dumazet
53
3.73%
7
14.00%
Toshiaki Makita
44
3.10%
1
2.00%
Ananda Raju
44
3.10%
1
2.00%
Tom Herbert
36
2.54%
3
6.00%
Ilan Tayari
35
2.46%
1
2.00%
Marcelo Ricardo Leitner
20
1.41%
1
2.00%
Arnaldo Carvalho de Melo
14
0.99%
4
8.00%
Vlad Yasevich
11
0.77%
2
4.00%
Wei-Chun Chao
7
0.49%
1
2.00%
Simon Horman
5
0.35%
1
2.00%
Mel Gorman
5
0.35%
1
2.00%
David S. Miller
3
0.21%
1
2.00%
Ian Campbell
1
0.07%
1
2.00%
Michał Mirosław
1
0.07%
1
2.00%
Total
1420
100.00%
50
100.00%


EXPORT_SYMBOL_GPL(skb_segment);



int skb_gro_receive(struct sk_buff **head, struct sk_buff *skb)
{
	struct skb_shared_info *pinfo, *skbinfo = skb_shinfo(skb);
	unsigned int offset = skb_gro_offset(skb);
	unsigned int headlen = skb_headlen(skb);
	unsigned int len = skb_gro_len(skb);
	struct sk_buff *lp, *p = *head;
	unsigned int delta_truesize;

	if (unlikely(p->len + len >= 65536))
		return -E2BIG;

	lp = NAPI_GRO_CB(p)->last;
	pinfo = skb_shinfo(lp);

	if (headlen <= offset) {
		skb_frag_t *frag;
		skb_frag_t *frag2;
		int i = skbinfo->nr_frags;
		int nr_frags = pinfo->nr_frags + i;

		if (nr_frags > MAX_SKB_FRAGS)
			goto merge;

		offset -= headlen;
		pinfo->nr_frags = nr_frags;
		skbinfo->nr_frags = 0;

		frag = pinfo->frags + nr_frags;
		frag2 = skbinfo->frags + i;
		do {
			*--frag = *--frag2;
		} while (--i);

		frag->page_offset += offset;
		skb_frag_size_sub(frag, offset);

		/* all fragments truesize : remove (head size + sk_buff) */
		delta_truesize = skb->truesize -
				 SKB_TRUESIZE(skb_end_offset(skb));

		skb->truesize -= skb->data_len;
		skb->len -= skb->data_len;
		skb->data_len = 0;

		NAPI_GRO_CB(skb)->free = NAPI_GRO_FREE;
		goto done;
	} else if (skb->head_frag) {
		int nr_frags = pinfo->nr_frags;
		skb_frag_t *frag = pinfo->frags + nr_frags;
		struct page *page = virt_to_head_page(skb->head);
		unsigned int first_size = headlen - offset;
		unsigned int first_offset;

		if (nr_frags + 1 + skbinfo->nr_frags > MAX_SKB_FRAGS)
			goto merge;

		first_offset = skb->data -
			       (unsigned char *)page_address(page) +
			       offset;

		pinfo->nr_frags = nr_frags + 1 + skbinfo->nr_frags;

		frag->page.p	  = page;
		frag->page_offset = first_offset;
		skb_frag_size_set(frag, first_size);

		memcpy(frag + 1, skbinfo->frags, sizeof(*frag) * skbinfo->nr_frags);
		/* We dont need to clear skbinfo->nr_frags here */

		delta_truesize = skb->truesize - SKB_DATA_ALIGN(sizeof(struct sk_buff));
		NAPI_GRO_CB(skb)->free = NAPI_GRO_FREE_STOLEN_HEAD;
		goto done;
	}

merge:
	delta_truesize = skb->truesize;
	if (offset > headlen) {
		unsigned int eat = offset - headlen;

		skbinfo->frags[0].page_offset += eat;
		skb_frag_size_sub(&skbinfo->frags[0], eat);
		skb->data_len -= eat;
		skb->len -= eat;
		offset = headlen;
	}

	__skb_pull(skb, offset);

	if (NAPI_GRO_CB(p)->last == p)
		skb_shinfo(p)->frag_list = skb;
	else
		NAPI_GRO_CB(p)->last->next = skb;
	NAPI_GRO_CB(p)->last = skb;
	__skb_header_release(skb);
	lp = p;

done:
	NAPI_GRO_CB(p)->count++;
	p->data_len += len;
	p->truesize += delta_truesize;
	p->len += len;
	if (lp != p) {
		lp->data_len += len;
		lp->truesize += delta_truesize;
		lp->len += len;
	}
	NAPI_GRO_CB(skb)->same_flow = 1;
	return 0;
}
Contributors
Person
Tokens
Prop
Commits
CommitProp
Herbert Xu
328
53.95%
17
50.00%
Eric Dumazet
259
42.60%
12
35.29%
Michal Schmidt
14
2.30%
1
2.94%
Arnaldo Carvalho de Melo
3
0.49%
2
5.88%
Mel Gorman
3
0.49%
1
2.94%
Alexander Duyck
1
0.16%
1
2.94%
Total
608
100.00%
34
100.00%


EXPORT_SYMBOL_GPL(skb_gro_receive);



void __init skb_init(void)
{
	skbuff_head_cache = kmem_cache_create("skbuff_head_cache",
					      sizeof(struct sk_buff),
					      0,
					      SLAB_HWCACHE_ALIGN|SLAB_PANIC,
					      NULL);
	skbuff_fclone_cache = kmem_cache_create("skbuff_fclone_cache",
						sizeof(struct sk_buff_fclones),
						0,
						SLAB_HWCACHE_ALIGN|SLAB_PANIC,
						NULL);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Linus Torvalds (pre-git)
23
46.00%
2
28.57%
David S. Miller
16
32.00%
1
14.29%
Herbert Xu
5
10.00%
1
14.29%
Alexey Dobriyan
4
8.00%
1
14.29%
Eric Dumazet
1
2.00%
1
14.29%
Mala Anand
1
2.00%
1
14.29%
Total
50
100.00%
7
100.00%

/**
 *      skb_to_sgvec - Fill a scatter-gather list from a socket buffer
 *      @skb: Socket buffer containing the buffers to be mapped
 *      @sg: The scatter-gather list to map into
 *      @offset: The offset into the buffer's contents to start mapping
 *      @len: Length of buffer space to be mapped
 *
 *      Fill the specified scatter-gather list with mappings/pointers into a
 *      region of the buffer space attached to a socket buffer.
 */

static int

__skb_to_sgvec(struct sk_buff *skb, struct scatterlist *sg, int offset, int len)
{
	int start = skb_headlen(skb);
	int i, copy = start - offset;
	struct sk_buff *frag_iter;
	int elt = 0;

	if (copy > 0) {
		if (copy > len)
			copy = len;
		sg_set_buf(sg, skb->data + offset, copy);
		elt++;
		if ((len -= copy) == 0)
			return elt;
		offset += copy;
	}

	for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
		int end;

		WARN_ON(start > offset + len);

		end = start + skb_frag_size(&skb_shinfo(skb)->frags[i]);
		if ((copy = end - offset) > 0) {
			skb_frag_t *frag = &skb_shinfo(skb)->frags[i];

			if (copy > len)
				copy = len;
			sg_set_page(&sg[elt], skb_frag_page(frag), copy,
					frag->page_offset+offset-start);
			elt++;
			if (!(len -= copy))
				return elt;
			offset += copy;
		}
		start = end;
	}

	skb_walk_frags(skb, frag_iter) {
		int end;

		WARN_ON(start > offset + len);

		end = start + frag_iter->len;
		if ((copy = end - offset) > 0) {
			if (copy > len)
				copy = len;
			elt += __skb_to_sgvec(frag_iter, sg+elt, offset - start,
					      copy);
			if ((len -= copy) == 0)
				return elt;
			offset += copy;
		}
		start = end;
	}
	BUG_ON(len);
	return elt;
}

Contributors
Person
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CommitProp
David Howells
188
56.29%
1
5.56%
Eric Dumazet
65
19.46%
5
27.78%
David S. Miller
43
12.87%
3
16.67%
Herbert Xu
13
3.89%
3
16.67%
Arnaldo Carvalho de Melo
10
2.99%
1
5.56%
Jens Axboe
8
2.40%
2
11.11%
Ilpo Järvinen
4
1.20%
1
5.56%
Ian Campbell
2
0.60%
1
5.56%
Christoph Hellwig
1
0.30%
1
5.56%
Total
334
100.00%
18
100.00%

/* As compared with skb_to_sgvec, skb_to_sgvec_nomark only map skb to given
 * sglist without mark the sg which contain last skb data as the end.
 * So the caller can mannipulate sg list as will when padding new data after
 * the first call without calling sg_unmark_end to expend sg list.
 *
 * Scenario to use skb_to_sgvec_nomark:
 * 1. sg_init_table
 * 2. skb_to_sgvec_nomark(payload1)
 * 3. skb_to_sgvec_nomark(payload2)
 *
 * This is equivalent to:
 * 1. sg_init_table
 * 2. skb_to_sgvec(payload1)
 * 3. sg_unmark_end
 * 4. skb_to_sgvec(payload2)
 *
 * When mapping mutilple payload conditionally, skb_to_sgvec_nomark
 * is more preferable.
 */


int skb_to_sgvec_nomark(struct sk_buff *skb, struct scatterlist *sg,
			int offset, int len)
{
	return __skb_to_sgvec(skb, sg, offset, len);
}
Contributors
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Fan Du
33
100.00%
1
100.00%
Total
33
100.00%
1
100.00%


EXPORT_SYMBOL_GPL(skb_to_sgvec_nomark);



int skb_to_sgvec(struct sk_buff *skb, struct scatterlist *sg, int offset, int len)
{
	int nsg = __skb_to_sgvec(skb, sg, offset, len);

	sg_mark_end(&sg[nsg - 1]);

	return nsg;
}
Contributors
Person
Tokens
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CommitProp
David S. Miller
42
85.71%
1
33.33%
Herbert Xu
6
12.24%
1
33.33%
Jens Axboe
1
2.04%
1
33.33%
Total
49
100.00%
3
100.00%


EXPORT_SYMBOL_GPL(skb_to_sgvec);

/**
 *      skb_cow_data - Check that a socket buffer's data buffers are writable
 *      @skb: The socket buffer to check.
 *      @tailbits: Amount of trailing space to be added
 *      @trailer: Returned pointer to the skb where the @tailbits space begins
 *
 *      Make sure that the data buffers attached to a socket buffer are
 *      writable. If they are not, private copies are made of the data buffers
 *      and the socket buffer is set to use these instead.
 *
 *      If @tailbits is given, make sure that there is space to write @tailbits
 *      bytes of data beyond current end of socket buffer.  @trailer will be
 *      set to point to the skb in which this space begins.
 *
 *      The number of scatterlist elements required to completely map the
 *      COW'd and extended socket buffer will be returned.
 */


int skb_cow_data(struct sk_buff *skb, int tailbits, struct sk_buff **trailer)
{
	int copyflag;
	int elt;
	struct sk_buff *skb1, **skb_p;

	/* If skb is cloned or its head is paged, reallocate
         * head pulling out all the pages (pages are considered not writable
         * at the moment even if they are anonymous).
         */
	if ((skb_cloned(skb) || skb_shinfo(skb)->nr_frags) &&
	    __pskb_pull_tail(skb, skb_pagelen(skb)-skb_headlen(skb)) == NULL)
		return -ENOMEM;

	/* Easy case. Most of packets will go this way. */
	if (!skb_has_frag_list(skb)) {
		/* A little of trouble, not enough of space for trailer.
                 * This should not happen, when stack is tuned to generate
                 * good frames. OK, on miss we reallocate and reserve even more
                 * space, 128 bytes is fair. */

		if (skb_tailroom(skb) < tailbits &&
		    pskb_expand_head(skb, 0, tailbits-skb_tailroom(skb)+128, GFP_ATOMIC))
			return -ENOMEM;

		/* Voila! */
		*trailer = skb;
		return 1;
	}

	/* Misery. We are in troubles, going to mincer fragments... */

	elt = 1;
	skb_p = &skb_shinfo(skb)->frag_list;
	copyflag = 0;

	while ((skb1 = *skb_p) != NULL) {
		int ntail = 0;

		/* The fragment is partially pulled by someone,
                 * this can happen on input. Copy it and everything
                 * after it. */

		if (skb_shared(skb1))
			copyflag = 1;

		/* If the skb is the last, worry about trailer. */

		if (skb1->next == NULL && tailbits) {
			if (skb_shinfo(skb1)->nr_frags ||
			    skb_has_frag_list(skb1) ||
			    skb_tailroom(skb1) < tailbits)
				ntail = tailbits + 128;
		}

		if (copyflag ||
		    skb_cloned(skb1) ||
		    ntail ||
		    skb_shinfo(skb1)->nr_frags ||
		    skb_has_frag_list(skb1)) {
			struct sk_buff *skb2;

			/* Fuck, we are miserable poor guys... */
			if (ntail == 0)
				skb2 = skb_copy(skb1, GFP_ATOMIC);
			else
				skb2 = skb_copy_expand(skb1,
						       skb_headroom(skb1),
						       ntail,
						       GFP_ATOMIC);
			if (unlikely(skb2 == NULL))
				return -ENOMEM;

			if (skb1->sk)
				skb_set_owner_w(skb2, skb1->sk);

			/* Looking around. Are we still alive?
                         * OK, link new skb, drop old one */

			skb2->next = skb1->next;
			*skb_p = skb2;
			kfree_skb(skb1);
			skb1 = skb2;
		}
		elt++;
		*trailer = skb1;
		skb_p = &skb1->next;
	}

	return elt;
}
Contributors
Person
Tokens
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Commits
CommitProp
David Howells
261
75.65%
1
7.14%
Herbert Xu
59
17.10%
7
50.00%
Eric Dumazet
20
5.80%
4
28.57%
David S. Miller
3
0.87%
1
7.14%
Michal Schmidt
2
0.58%
1
7.14%
Total
345
100.00%
14
100.00%


EXPORT_SYMBOL_GPL(skb_cow_data);



static void sock_rmem_free(struct sk_buff *skb)
{
	struct sock *sk = skb->sk;

	atomic_sub(skb->truesize, &sk->sk_rmem_alloc);
}

Contributors
Person
Tokens
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CommitProp
Eric Dumazet
26
81.25%
1
33.33%
Linus Torvalds (pre-git)
6
18.75%
2
66.67%
Total
32
100.00%
3
100.00%



static void skb_set_err_queue(struct sk_buff *skb)
{
	/* pkt_type of skbs received on local sockets is never PACKET_OUTGOING.
         * So, it is safe to (mis)use it to mark skbs on the error queue.
         */
	skb->pkt_type = PACKET_OUTGOING;
	BUILD_BUG_ON(PACKET_OUTGOING == 0);
}

Contributors
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CommitProp
Soheil Hassas Yeganeh
25
100.00%
1
100.00%
Total
25
100.00%
1
100.00%

/*
 * Note: We dont mem charge error packets (no sk_forward_alloc changes)
 */


int sock_queue_err_skb(struct sock *sk, struct sk_buff *skb)
{
	if (atomic_read(&sk->sk_rmem_alloc) + skb->truesize >=
	    (unsigned int)sk->sk_rcvbuf)
		return -ENOMEM;

	skb_orphan(skb);
	skb->sk = sk;
	skb->destructor = sock_rmem_free;
	atomic_add(skb->truesize, &sk->sk_rmem_alloc);
	skb_set_err_queue(skb);

	/* before exiting rcu section, make sure dst is refcounted */
	skb_dst_force(skb);

	skb_queue_tail(&sk->sk_error_queue, skb);
	if (!sock_flag(sk, SOCK_DEAD))
		sk->sk_data_ready(sk);
	return 0;
}
Contributors
Person
Tokens
Prop
Commits
CommitProp
Eric Dumazet
91
81.98%
3
50.00%
David S. Miller
10
9.01%
1
16.67%
Linus Torvalds (pre-git)
5
4.50%
1
16.67%
Soheil Hassas Yeganeh
5
4.50%
1
16.67%
Total
111
100.00%
6
100.00%


EXPORT_SYMBOL(sock_queue_err_skb);



static bool is_icmp_err_skb(const struct sk_buff *skb)
{
	return skb && (SKB_EXT_ERR(skb)->ee.ee_origin == SO_EE_ORIGIN_ICMP ||
		       SKB_EXT_ERR(skb)->ee.ee_origin == SO_EE_ORIGIN_ICMP6);
}

Contributors
Person
Tokens
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CommitProp
Soheil Hassas Yeganeh
39
100.00%
1
100.00%
Total
39
100.00%
1
100.00%



struct sk_buff *sock_dequeue_err_skb(struct sock *sk)
{
	struct sk_buff_head *q = &sk->sk_error_queue;
	struct sk_buff *skb, *skb_next = NULL;
	bool icmp_next = false;
	unsigned long flags;

	spin_lock_irqsave(&q->lock, flags);
	skb = __skb_dequeue(q);
	if (skb && (skb_next = skb_peek(q)))
		icmp_next = is_icmp_err_skb(skb_next);
	spin_unlock_irqrestore(&q->lock, flags);

	if (is_icmp_err_skb(skb) && !icmp_next)
		sk->sk_err = 0;

	if (skb_next)
		sk->sk_error_report(sk);

	return skb;
}
Contributors
Person
Tokens
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Commits
CommitProp
Willem de Bruijn
82
69.49%
1
33.33%
Soheil Hassas Yeganeh
26
22.03%
1
33.33%
Eric Dumazet
10
8.47%
1
33.33%
Total
118
100.00%
3
100.00%


EXPORT_SYMBOL(sock_dequeue_err_skb);

/**
 * skb_clone_sk - create clone of skb, and take reference to socket
 * @skb: the skb to clone
 *
 * This function creates a clone of a buffer that holds a reference on
 * sk_refcnt.  Buffers created via this function are meant to be
 * returned using sock_queue_err_skb, or free via kfree_skb.
 *
 * When passing buffers allocated with this function to sock_queue_err_skb
 * it is necessary to wrap the call with sock_hold/sock_put in order to
 * prevent the socket from being released prior to being enqueued on
 * the sk_error_queue.
 */


struct sk_buff *skb_clone_sk(struct sk_buff *skb)
{
	struct sock *sk = skb->sk;
	struct sk_buff *clone;

	if (!sk || !atomic_inc_not_zero(&sk->sk_refcnt))
		return NULL;

	clone = skb_clone(skb, GFP_ATOMIC);
	if (!clone) {
		sock_put(sk);
		return NULL;
	}

	clone->sk = sk;
	clone->destructor = sock_efree;

	return clone;
}
Contributors
Person
Tokens
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CommitProp
Alexander Duyck
82
100.00%
1
100.00%
Total
82
100.00%
1
100.00%


EXPORT_SYMBOL(skb_clone_sk);



static void __skb_complete_tx_timestamp(struct sk_buff *skb,
					struct sock *sk,
					int tstype,
					bool opt_stats)
{
	struct sock_exterr_skb *serr;
	int err;

	BUILD_BUG_ON(sizeof(struct sock_exterr_skb) > sizeof(skb->cb));

	serr = SKB_EXT_ERR(skb);
	memset(serr, 0, sizeof(*serr));
	serr->ee.ee_errno = ENOMSG;
	serr->ee.ee_origin = SO_EE_ORIGIN_TIMESTAMPING;
	serr->ee.ee_info = tstype;
	serr->opt_stats = opt_stats;
	serr->header.h4.iif = skb->dev ? skb->dev->ifindex : 0;
	if (sk->sk_tsflags & SOF_TIMESTAMPING_OPT_ID) {
		serr->ee.ee_data = skb_shinfo(skb)->tskey;
		if (sk->sk_protocol == IPPROTO_TCP &&
		    sk->sk_type == SOCK_STREAM)
			serr->ee.ee_data -= sk->sk_tskey;
	}

	err = sock_queue_err_skb(sk, skb);

	if (err)
		kfree_skb(skb);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Willem de Bruijn
75
41.44%
5
38.46%
Patrick Ohly
56
30.94%
1
7.69%
Soheil Hassas Yeganeh
25
13.81%
1
7.69%
David Howells
11
6.08%
1
7.69%
Américo Wang
6
3.31%
1
7.69%
Alexander Duyck
3
1.66%
1
7.69%
Jens Axboe
2
1.10%
1
7.69%
Arnaldo Carvalho de Melo
2
1.10%
1
7.69%
Christoph Hellwig
1
0.55%
1
7.69%
Total
181
100.00%
13
100.00%



static bool skb_may_tx_timestamp(struct sock *sk, bool tsonly)
{
	bool ret;

	if (likely(sysctl_tstamp_allow_data || tsonly))
		return true;

	read_lock_bh(&sk->sk_callback_lock);
	ret = sk->sk_socket && sk->sk_socket->file &&
	      file_ns_capable(sk->sk_socket->file, &init_user_ns, CAP_NET_RAW);
	read_unlock_bh(&sk->sk_callback_lock);
	return ret;
}

Contributors
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Willem de Bruijn
74
100.00%
1
100.00%
Total
74
100.00%
1
100.00%



void skb_complete_tx_timestamp(struct sk_buff *skb,
			       struct skb_shared_hwtstamps *hwtstamps)
{
	struct sock *sk = skb->sk;

	if (!skb_may_tx_timestamp(sk, false))
		return;

	/* Take a reference to prevent skb_orphan() from freeing the socket,
         * but only if the socket refcount is not zero.
         */
	if (likely(atomic_inc_not_zero(&sk->sk_refcnt))) {
		*skb_hwtstamps(skb) = *hwtstamps;
		__skb_complete_tx_timestamp(skb, sk, SCM_TSTAMP_SND, false);
		sock_put(sk);
	}
}
Contributors
Person
Tokens
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CommitProp
Alexander Duyck
50
65.79%
2
40.00%
Eric Dumazet
13
17.11%
1
20.00%
Willem de Bruijn
11
14.47%
1
20.00%
Soheil Hassas Yeganeh
2
2.63%
1
20.00%
Total
76
100.00%
5
100.00%


EXPORT_SYMBOL_GPL(skb_complete_tx_timestamp);



void __skb_tstamp_tx(struct sk_buff *orig_skb,
		     struct skb_shared_hwtstamps *hwtstamps,
		     struct sock *sk, int tstype)
{
	struct sk_buff *skb;
	bool tsonly, opt_stats = false;

	if (!sk)
		return;

	tsonly = sk->sk_tsflags & SOF_TIMESTAMPING_OPT_TSONLY;
	if (!skb_may_tx_timestamp(sk, tsonly))
		return;

	if (tsonly) {
#ifdef CONFIG_INET
		if ((sk->sk_tsflags & SOF_TIMESTAMPING_OPT_STATS) &&
		    sk->sk_protocol == IPPROTO_TCP &&
		    sk->sk_type == SOCK_STREAM) {
			skb = tcp_get_timestamping_opt_stats(sk);
			opt_stats = true;
		} else
#endif
			skb = alloc_skb(0, GFP_ATOMIC);
	} else {
		skb = skb_clone(orig_skb, GFP_ATOMIC);
	}
	if (!skb)
		return;

	if (tsonly) {
		skb_shinfo(skb)->tx_flags = skb_shinfo(orig_skb)->tx_flags;
		skb_shinfo(skb)->tskey = skb_shinfo(orig_skb)->tskey;
	}

	if (hwtstamps)
		*skb_hwtstamps(skb) = *hwtstamps;
	else
		skb->tstamp = ktime_get_real();

	__skb_complete_tx_timestamp(skb, sk, tstype, opt_stats);
}
Contributors
Person
Tokens
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CommitProp
Willem de Bruijn
85
42.50%
3
50.00%
Alexander Duyck
64
32.00%
1
16.67%
Francis Yan
39
19.50%
1
16.67%
Soheil Hassas Yeganeh
12
6.00%
1
16.67%
Total
200
100.00%
6
100.00%


EXPORT_SYMBOL_GPL(__skb_tstamp_tx);



void skb_tstamp_tx(struct sk_buff *orig_skb,
		   struct skb_shared_hwtstamps *hwtstamps)
{
	return __skb_tstamp_tx(orig_skb, hwtstamps, orig_skb->sk,
			       SCM_TSTAMP_SND);
}
Contributors
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Willem de Bruijn
29
100.00%
1
100.00%
Total
29
100.00%
1
100.00%


EXPORT_SYMBOL_GPL(skb_tstamp_tx);



void skb_complete_wifi_ack(struct sk_buff *skb, bool acked)
{
	struct sock *sk = skb->sk;
	struct sock_exterr_skb *serr;
	int err = 1;

	skb->wifi_acked_valid = 1;
	skb->wifi_acked = acked;

	serr = SKB_EXT_ERR(skb);
	memset(serr, 0, sizeof(*serr));
	serr->ee.ee_errno = ENOMSG;
	serr->ee.ee_origin = SO_EE_ORIGIN_TXSTATUS;

	/* Take a reference to prevent skb_orphan() from freeing the socket,
         * but only if the socket refcount is not zero.
         */
	if (likely(atomic_inc_not_zero(&sk->sk_refcnt))) {
		err = sock_queue_err_skb(sk, skb);
		sock_put(sk);
	}
	if (err)
		kfree_skb(skb);
}
Contributors
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CommitProp
Johannes Berg
72
60.50%
1
11.11%
Eric Dumazet
20
16.81%
1
11.11%
David Howells
12
10.08%
1
11.11%
Arnaldo Carvalho de Melo
4
3.36%
1
11.11%
David S. Miller
3
2.52%
1
11.11%
Alexander Duyck
3
2.52%
1
11.11%
Jens Axboe
3
2.52%
2
22.22%
Ian Campbell
2
1.68%
1
11.11%
Total
119
100.00%
9
100.00%


EXPORT_SYMBOL_GPL(skb_complete_wifi_ack);

/**
 * skb_partial_csum_set - set up and verify partial csum values for packet
 * @skb: the skb to set
 * @start: the number of bytes after skb->data to start checksumming.
 * @off: the offset from start to place the checksum.
 *
 * For untrusted partially-checksummed packets, we need to make sure the values
 * for skb->csum_start and skb->csum_offset are valid so we don't oops.
 *
 * This function checks and sets those values and skb->ip_summed: if this
 * returns false you should drop the packet.
 */


bool skb_partial_csum_set(struct sk_buff *skb, u16 start, u16 off)
{
	if (unlikely(start > skb_headlen(skb)) ||
	    unlikely((int)start + off > skb_headlen(skb) - 2)) {
		net_warn_ratelimited("bad partial csum: csum=%u/%u len=%u\n",
				     start, off, skb_headlen(skb));
		return false;
	}
	skb->ip_summed = CHECKSUM_PARTIAL;
	skb->csum_start = skb_headroom(skb) + start;
	skb->csum_offset = off;
	skb_set_transport_header(skb, start);
	return true;
}
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CommitProp
Rusty Russell
55
56.70%
1
12.50%
David Howells
17
17.53%
1
12.50%
David S. Miller
12
12.37%
2
25.00%
Herbert Xu
7
7.22%
1
12.50%
Jason (Hui) Wang
4
4.12%
1
12.50%
Joe Perches
1
1.03%
1
12.50%
Ilpo Järvinen
1
1.03%
1
12.50%
Total
97
100.00%
8
100.00%


EXPORT_SYMBOL_GPL(skb_partial_csum_set);



static int skb_maybe_pull_tail(struct sk_buff *skb, unsigned int len,
			       unsigned int max)
{
	if (skb_headlen(skb) >= len)
		return 0;

	/* If we need to pullup then pullup to the max, so we
         * won't need to do it again.
         */
	if (max > skb->len)
		max = skb->len;

	if (__pskb_pull_tail(skb, max - skb_headlen(skb)) == NULL)
		return -ENOMEM;

	if (skb_headlen(skb) < len)
		return -EPROTO;

	return 0;
}

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David Howells
48
58.54%
1
50.00%
Paul Durrant
34
41.46%
1
50.00%
Total
82
100.00%
2
100.00%


#define MAX_TCP_HDR_LEN (15 * 4)


static __sum16 *skb_checksum_setup_ip(struct sk_buff *skb,
				      typeof(IPPROTO_IP) proto,
				      unsigned int off)
{
	switch (proto) {
		int err;

	case IPPROTO_TCP:
		err = skb_maybe_pull_tail(skb, off + sizeof(struct tcphdr),
					  off + MAX_TCP_HDR_LEN);
		if (!err && !skb_partial_csum_set(skb, off,
						  offsetof(struct tcphdr,
							   check)))
			err = -EPROTO;
		return err ? ERR_PTR(err) : &tcp_hdr(skb)->check;

	case IPPROTO_UDP:
		err = skb_maybe_pull_tail(skb, off + sizeof(struct udphdr),
					  off + sizeof(struct udphdr));
		if (!err && !skb_partial_csum_set(skb, off,
						  offsetof(struct udphdr,
							   check)))
			err = -EPROTO;
		return err ? ERR_PTR(err) : &udp_hdr(skb)->check;
	}

	return ERR_PTR(-EPROTO);
}

/* This value should be large enough to cover a tagged ethernet header plus
 * maximally sized IP and TCP or UDP headers.
 */

#define MAX_IP_HDR_LEN 128



static int skb_checksum_setup_ipv4(struct sk_buff *skb, bool recalculate)
{
	unsigned int off;
	bool fragment;
	__sum16 *csum;
	int err;

	fragment = false;

	err = skb_maybe_pull_tail(skb,
				  sizeof(struct iphdr),
				  MAX_IP_HDR_LEN);
	if (err < 0)
		goto out;

	if (ip_hdr(skb)->frag_off & htons(IP_OFFSET | IP_MF))
		fragment = true;

	off = ip_hdrlen(skb);

	err = -EPROTO;

	if (fragment)
		goto out;

	csum = skb_checksum_setup_ip(skb, ip_hdr(skb)->protocol, off);
	if (IS_ERR(csum))
		return PTR_ERR(csum);

	if (recalculate)
		*csum = ~csum_tcpudp_magic(ip_hdr(skb)->saddr,
					   ip_hdr(skb)->daddr,
					   skb->len - off,
					   ip_hdr(skb)->protocol, 0);
	err = 0;

out:
	return err;
}

Contributors
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CommitProp
Jan Beulich
89
51.45%
1
20.00%
Paul Durrant
57
32.95%
1
20.00%
David Howells
16
9.25%
1
20.00%
Eric Dumazet
10
5.78%
1
20.00%
David S. Miller
1
0.58%
1
20.00%
Total
173
100.00%
5
100.00%

/* This value should be large enough to cover a tagged ethernet header plus
 * an IPv6 header, all options, and a maximal TCP or UDP header.
 */

#define MAX_IPV6_HDR_LEN 256


#define OPT_HDR(type, skb, off) \
	(type *)(skb_network_header(skb) + (off))



static int skb_checksum_setup_ipv6(struct sk_buff *skb, bool recalculate)
{
	int err;
	u8 nexthdr;
	unsigned int off;
	unsigned int len;
	bool fragment;
	bool done;
	__sum16 *csum;

	fragment = false;
	done = false;

	off = sizeof(struct ipv6hdr);

	err = skb_maybe_pull_tail(skb, off, MAX_IPV6_HDR_LEN);
	if (err < 0)
		goto out;

	nexthdr = ipv6_hdr(skb)->nexthdr;

	len = sizeof(struct ipv6hdr) + ntohs(ipv6_hdr(skb)->payload_len);
	while (off <= len && !done) {
		switch (nexthdr) {
		case IPPROTO_DSTOPTS:
		case IPPROTO_HOPOPTS:
		case IPPROTO_ROUTING: {
			struct ipv6_opt_hdr *hp;

			err = skb_maybe_pull_tail(skb,
						  off +
						  sizeof(struct ipv6_opt_hdr),
						  MAX_IPV6_HDR_LEN);
			if (err < 0)
				goto out;

			hp = OPT_HDR(struct ipv6_opt_hdr, skb, off);
			nexthdr = hp->nexthdr;
			off += ipv6_optlen(hp);
			break;
		}
		case IPPROTO_AH: {
			struct ip_auth_hdr *hp;

			err = skb_maybe_pull_tail(skb,
						  off +
						  sizeof(struct ip_auth_hdr),
						  MAX_IPV6_HDR_LEN);
			if (err < 0)
				goto out;

			hp = OPT_HDR(struct ip_auth_hdr, skb, off);
			nexthdr = hp->nexthdr;
			off += ipv6_authlen(hp);
			break;
		}
		case IPPROTO_FRAGMENT: {
			struct frag_hdr *hp;

			err = skb_maybe_pull_tail(skb,
						  off +
						  sizeof(struct frag_hdr),
						  MAX_IPV6_HDR_LEN);
			if (err < 0)
				goto out;

			hp = OPT_HDR(struct frag_hdr, skb, off);

			if (hp->frag_off & htons(IP6_OFFSET | IP6_MF))
				fragment = true;

			nexthdr = hp->nexthdr;
			off += sizeof(struct frag_hdr);
			break;
		}
		default:
			done = true;
			break;
		}
	}

	err = -EPROTO;

	if (!done || fragment)
		goto out;

	csum = skb_checksum_setup_ip(skb, nexthdr, off);
	if (IS_ERR(csum))
		return PTR_ERR(csum);

	if (recalculate)
		*csum = ~csum_ipv6_magic(&ipv6_hdr(skb)->saddr,
					 &ipv6_hdr(skb)->daddr,
					 skb->len - off, nexthdr, 0);
	err = 0;

out:
	return err;
}

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Paul Durrant
305
72.79%
1
9.09%
Patrick Ohly
37
8.83%
1
9.09%
Eric Dumazet
34
8.11%
4
36.36%
Jan Beulich
16
3.82%
1
9.09%
Rusty Russell
11
2.63%
1
9.09%
Willem de Bruijn
8
1.91%
1
9.09%
Johannes Berg
4
0.95%
1
9.09%
Herbert Xu
4
0.95%
1
9.09%
Total
419
100.00%
11
100.00%

/**
 * skb_checksum_setup - set up partial checksum offset
 * @skb: the skb to set up
 * @recalculate: if true the pseudo-header checksum will be recalculated
 */


int skb_checksum_setup(struct sk_buff *skb, bool recalculate)
{
	int err;

	switch (skb->protocol) {
	case htons(ETH_P_IP):
		err = skb_checksum_setup_ipv4(skb, recalculate);
		break;

	case htons(ETH_P_IPV6):
		err = skb_checksum_setup_ipv6(skb, recalculate);
		break;

	default:
		err = -EPROTO;
		break;
	}

	return err;
}
Contributors
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Tokens
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Commits
CommitProp
Paul Durrant
48
72.73%
1
25.00%
Rusty Russell
12
18.18%
1
25.00%
Jason (Hui) Wang
5
7.58%
1
25.00%
Jan Beulich
1
1.52%
1
25.00%
Total
66
100.00%
4
100.00%


EXPORT_SYMBOL(skb_checksum_setup);

/**
 * skb_checksum_maybe_trim - maybe trims the given skb
 * @skb: the skb to check
 * @transport_len: the data length beyond the network header
 *
 * Checks whether the given skb has data beyond the given transport length.
 * If so, returns a cloned skb trimmed to this transport length.
 * Otherwise returns the provided skb. Returns NULL in error cases
 * (e.g. transport_len exceeds skb length or out-of-memory).
 *
 * Caller needs to set the skb transport header and free any returned skb if it
 * differs from the provided skb.
 */


static struct sk_buff *skb_checksum_maybe_trim(struct sk_buff *skb,
					       unsigned int transport_len)
{
	struct sk_buff *skb_chk;
	unsigned int len = skb_transport_offset(skb) + transport_len;
	int ret;

	if (skb->len < len)
		return NULL;
	else if (skb->len == len)
		return skb;

	skb_chk = skb_clone(skb, GFP_ATOMIC);
	if (!skb_chk)
		return NULL;

	ret = pskb_trim_rcsum(skb_chk, len);
	if (ret) {
		kfree_skb(skb_chk);
		return NULL;
	}

	return skb_chk;
}

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Linus Lüssing
102
100.00%
1
100.00%
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102
100.00%
1
100.00%

/**
 * skb_checksum_trimmed - validate checksum of an skb
 * @skb: the skb to check
 * @transport_len: the data length beyond the network header
 * @skb_chkf: checksum function to use
 *
 * Applies the given checksum function skb_chkf to the provided skb.
 * Returns a checked and maybe trimmed skb. Returns NULL on error.
 *
 * If the skb has data beyond the given transport length, then a
 * trimmed & cloned skb is checked and returned.
 *
 * Caller needs to set the skb transport header and free any returned skb if it
 * differs from the provided skb.
 */


struct sk_buff *skb_checksum_trimmed(struct sk_buff *skb,
				     unsigned int transport_len,
				     __sum16(*skb_chkf)(struct sk_buff *skb))
{
	struct sk_buff *skb_chk;
	unsigned int offset = skb_transport_offset(skb);
	__sum16 ret;

	skb_chk = skb_checksum_maybe_trim(skb, transport_len);
	if (!skb_chk)
		goto err;

	if (!pskb_may_pull(skb_chk, offset))
		goto err;

	skb_pull_rcsum(skb_chk, offset);
	ret = skb_chkf(skb_chk);
	skb_push_rcsum(skb_chk, offset);

	if (ret)
		goto err;

	return skb_chk;

err:
	if (skb_chk && skb_chk != skb)
		kfree_skb(skb_chk);

	return NULL;

}
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Linus Lüssing
124
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4
100.00%
Total
124
100.00%
4
100.00%


EXPORT_SYMBOL(skb_checksum_trimmed);



void __skb_warn_lro_forwarding(const struct sk_buff *skb)
{
	net_warn_ratelimited("%s: received packets cannot be forwarded while LRO is enabled\n",
			     skb->dev->name);
}
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Ben Hutchings
20
90.91%
1
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2
9.09%
1
50.00%
Total
22
100.00%
2
100.00%


EXPORT_SYMBOL(__skb_warn_lro_forwarding);



void kfree_skb_partial(struct sk_buff *skb, bool head_stolen)
{
	if (head_stolen) {
		skb_release_head_state(skb);
		kmem_cache_free(skbuff_head_cache, skb);
	} else {
		__kfree_skb(skb);
	}
}
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39
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2
100.00%
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39
100.00%
2
100.00%


EXPORT_SYMBOL(kfree_skb_partial);

/**
 * skb_try_coalesce - try to merge skb to prior one
 * @to: prior buffer
 * @from: buffer to add
 * @fragstolen: pointer to boolean
 * @delta_truesize: how much more was allocated than was requested
 */


bool skb_try_coalesce(struct sk_buff *to, struct sk_buff *from,
		      bool *fragstolen, int *delta_truesize)
{
	int i, delta, len = from->len;

	*fragstolen = false;

	if (skb_cloned(to))
		return false;

	if (len <= skb_tailroom(to)) {
		if (len)
			BUG_ON(skb_copy_bits(from, 0, skb_put(to, len), len));
		*delta_truesize = 0;
		return true;
	}

	if (skb_has_frag_list(to) || skb_has_frag_list(from))
		return false;

	if (skb_headlen(from) != 0) {
		struct page *page;
		unsigned int offset;

		if (skb_shinfo(to)->nr_frags +
		    skb_shinfo(from)->nr_frags >= MAX_SKB_FRAGS)
			return false;

		if (skb_head_is_locked(from))
			return false;

		delta = from->truesize - SKB_DATA_ALIGN(sizeof(struct sk_buff));

		page = virt_to_head_page(from->head);
		offset = from->data - (unsigned char *)page_address(page);

		skb_fill_page_desc(to, skb_shinfo(to)->nr_frags,
				   page, offset, skb_headlen(from));
		*fragstolen = true;
	} else {
		if (skb_shinfo(to)->nr_frags +
		    skb_shinfo(from)->nr_frags > MAX_SKB_FRAGS)
			return false;

		delta = from->truesize - SKB_TRUESIZE(skb_end_offset(from));
	}

	WARN_ON_ONCE(delta < len);

	memcpy(skb_shinfo(to)->frags + skb_shinfo(to)->nr_frags,
	       skb_shinfo(from)->frags,
	       skb_shinfo(from)->nr_frags * sizeof(skb_frag_t));
	skb_shinfo(to)->nr_frags += skb_shinfo(from)->nr_frags;

	if (!skb_cloned(from))
		skb_shinfo(from)->nr_frags = 0;

	/* if the skb is not cloned this does nothing
         * since we set nr_frags to 0.
         */
	for (i = 0; i < skb_shinfo(from)->nr_frags; i++)
		skb_frag_ref(from, i);

	to->truesize += delta;
	to->len += len;
	to->data_len += len;

	*delta_truesize = delta;
	return true;
}
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Eric Dumazet
385
99.48%
2
50.00%
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1
0.26%
1
25.00%
Weiping Pan (潘卫平)
1
0.26%
1
25.00%
Total
387
100.00%
4
100.00%


EXPORT_SYMBOL(skb_try_coalesce);

/**
 * skb_scrub_packet - scrub an skb
 *
 * @skb: buffer to clean
 * @xnet: packet is crossing netns
 *
 * skb_scrub_packet can be used after encapsulating or decapsulting a packet
 * into/from a tunnel. Some information have to be cleared during these
 * operations.
 * skb_scrub_packet can also be used to clean a skb before injecting it in
 * another namespace (@xnet == true). We have to clear all information in the
 * skb that could impact namespace isolation.
 */


void skb_scrub_packet(struct sk_buff *skb, bool xnet)
{
	skb->tstamp = 0;
	skb->pkt_type = PACKET_HOST;
	skb->skb_iif = 0;
	skb->ignore_df = 0;
	skb_dst_drop(skb);
	secpath_reset(skb);
	nf_reset(skb);
	nf_reset_trace(skb);

	if (!xnet)
		return;

	skb_orphan(skb);
	skb->mark = 0;
}
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Nicolas Dichtel
51
68.92%
2
40.00%
Herbert Xu
17
22.97%
1
20.00%
Hannes Frederic Sowa
5
6.76%
1
20.00%
Américo Wang
1
1.35%
1
20.00%
Total
74
100.00%
5
100.00%


EXPORT_SYMBOL_GPL(skb_scrub_packet);

/**
 * skb_gso_transport_seglen - Return length of individual segments of a gso packet
 *
 * @skb: GSO skb
 *
 * skb_gso_transport_seglen is used to determine the real size of the
 * individual segments, including Layer4 headers (TCP/UDP).
 *
 * The MAC/L2 or network (IP, IPv6) headers are not accounted for.
 */


unsigned int skb_gso_transport_seglen(const struct sk_buff *skb)
{
	const struct skb_shared_info *shinfo = skb_shinfo(skb);
	unsigned int thlen = 0;

	if (skb->encapsulation) {
		thlen = skb_inner_transport_header(skb) -
			skb_transport_header(skb);

		if (likely(shinfo->gso_type & (SKB_GSO_TCPV4 | SKB_GSO_TCPV6)))
			thlen += inner_tcp_hdrlen(skb);
	} else if (likely(shinfo->gso_type & (SKB_GSO_TCPV4 | SKB_GSO_TCPV6))) {
		thlen = tcp_hdrlen(skb);
	} else if (unlikely(shinfo->gso_type & SKB_GSO_SCTP)) {
		thlen = sizeof(struct sctphdr);
	}
	/* UFO sets gso_size to the size of the fragmentation
         * payload, i.e. the size of the L4 (UDP) header is already
         * accounted for.
         */
	return thlen + shinfo->gso_size;
}
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104
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126
100.00%
4
100.00%


EXPORT_SYMBOL_GPL(skb_gso_transport_seglen);

/**
 * skb_gso_validate_mtu - Return in case such skb fits a given MTU
 *
 * @skb: GSO skb
 * @mtu: MTU to validate against
 *
 * skb_gso_validate_mtu validates if a given skb will fit a wanted MTU
 * once split.
 */


bool skb_gso_validate_mtu(const struct sk_buff *skb, unsigned int mtu)
{
	const struct skb_shared_info *shinfo = skb_shinfo(skb);
	const struct sk_buff *iter;
	unsigned int hlen;

	hlen = skb_gso_network_seglen(skb);

	if (shinfo->gso_size != GSO_BY_FRAGS)
		return hlen <= mtu;

	/* Undo this so we can re-use header sizes */
	hlen -= GSO_BY_FRAGS;

	skb_walk_frags(skb, iter) {
		if (hlen + skb_headlen(iter) > mtu)
			return false;
	}

	return true;
}
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86
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100.00%


EXPORT_SYMBOL_GPL(skb_gso_validate_mtu);



static struct sk_buff *skb_reorder_vlan_header(struct sk_buff *skb)
{
	if (skb_cow(skb, skb_headroom(skb)) < 0) {
		kfree_skb(skb);
		return NULL;
	}

	memmove(skb->data - ETH_HLEN, skb->data - skb->mac_len - VLAN_HLEN,
		2 * ETH_ALEN);
	skb->mac_header += VLAN_HLEN;
	return skb;
}

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Vlad Yasevich
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69
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3
100.00%



struct sk_buff *skb_vlan_untag(struct sk_buff *skb)
{
	struct vlan_hdr *vhdr;
	u16 vlan_tci;

	if (unlikely(skb_vlan_tag_present(skb))) {
		/* vlan_tci is already set-up so leave this for another time */
		return skb;
	}

	skb = skb_share_check(skb, GFP_ATOMIC);
	if (unlikely(!skb))
		goto err_free;

	if (unlikely(!pskb_may_pull(skb, VLAN_HLEN)))
		goto err_free;

	vhdr = (struct vlan_hdr *)skb->data;
	vlan_tci = ntohs(vhdr->h_vlan_TCI);
	__vlan_hwaccel_put_tag(skb, skb->protocol, vlan_tci);

	skb_pull_rcsum(skb, VLAN_HLEN);
	vlan_set_encap_proto(skb, vhdr);

	skb = skb_reorder_vlan_header(skb);
	if (unlikely(!skb))
		goto err_free;

	skb_reset_network_header(skb);
	skb_reset_transport_header(skb);
	skb_reset_mac_len(skb);

	return skb;

err_free:
	kfree_skb(skb);
	return NULL;
}
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1
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Total
163
100.00%
2
100.00%


EXPORT_SYMBOL(skb_vlan_untag);



int skb_ensure_writable(struct sk_buff *skb, int write_len)
{
	if (!pskb_may_pull(skb, write_len))
		return -ENOMEM;

	if (!skb_cloned(skb) || skb_clone_writable(skb, write_len))
		return 0;

	return pskb_expand_head(skb, 0, 0, GFP_ATOMIC);
}
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57
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57
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1
100.00%


EXPORT_SYMBOL(skb_ensure_writable);

/* remove VLAN header from packet and update csum accordingly.
 * expects a non skb_vlan_tag_present skb with a vlan tag payload
 */


int __skb_vlan_pop(struct sk_buff *skb, u16 *vlan_tci)
{
	struct vlan_hdr *vhdr;
	int offset = skb->data - skb_mac_header(skb);
	int err;

	if (WARN_ONCE(offset,
		      "__skb_vlan_pop got skb with skb->data not at mac header (offset %d)\n",
		      offset)) {
		return -EINVAL;
	}

	err = skb_ensure_writable(skb, VLAN_ETH_HLEN);
	if (unlikely(err))
		return err;

	skb_postpull_rcsum(skb, skb->data + (2 * ETH_ALEN), VLAN_HLEN);

	vhdr = (struct vlan_hdr *)(skb->data + ETH_HLEN);
	*vlan_tci = ntohs(vhdr->h_vlan_TCI);

	memmove(skb->data + VLAN_HLEN, skb->data, 2 * ETH_ALEN);
	__skb_pull(skb, VLAN_HLEN);

	vlan_set_encap_proto(skb, vhdr);
	skb->mac_header += VLAN_HLEN;

	if (skb_network_offset(skb) < ETH_HLEN)
		skb_set_network_header(skb, ETH_HLEN);

	skb_reset_mac_len(skb);

	return err;
}
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Jiri Pirko
157
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16
9.25%
1
50.00%
Total
173
100.00%
2
100.00%


EXPORT_SYMBOL(__skb_vlan_pop);

/* Pop a vlan tag either from hwaccel or from payload.
 * Expects skb->data at mac header.
 */


int skb_vlan_pop(struct sk_buff *skb)
{
	u16 vlan_tci;
	__be16 vlan_proto;
	int err;

	if (likely(skb_vlan_tag_present(skb))) {
		skb->vlan_tci = 0;
	} else {
		if (unlikely(!eth_type_vlan(skb->protocol)))
			return 0;

		err = __skb_vlan_pop(skb, &vlan_tci);
		if (err)
			return err;
	}
	/* move next vlan tag to hw accel tag */
	if (likely(!eth_type_vlan(skb->protocol)))
		return 0;

	vlan_proto = skb->protocol;
	err = __skb_vlan_pop(skb, &vlan_tci);
	if (unlikely(err))
		return err;

	__vlan_hwaccel_put_tag(skb, vlan_proto, vlan_tci);
	return 0;
}
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Jiri Pirko
124
96.88%
2
66.67%
Shmulik Ladkani
4
3.12%
1
33.33%
Total
128
100.00%
3
100.00%


EXPORT_SYMBOL(skb_vlan_pop);

/* Push a vlan tag either into hwaccel or into payload (if hwaccel tag present).
 * Expects skb->data at mac header.
 */


int skb_vlan_push(struct sk_buff *skb, __be16 vlan_proto, u16 vlan_tci)
{
	if (skb_vlan_tag_present(skb)) {
		int offset = skb->data - skb_mac_header(skb);
		int err;

		if (WARN_ONCE(offset,
			      "skb_vlan_push got skb with skb->data not at mac header (offset %d)\n",
			      offset)) {
			return -EINVAL;
		}

		err = __vlan_insert_tag(skb, skb->vlan_proto,
					skb_vlan_tag_get(skb));
		if (err)
			return err;

		skb->protocol = skb->vlan_proto;
		skb->mac_len += VLAN_HLEN;

		skb_postpush_rcsum(skb, skb->data + (2 * ETH_ALEN), VLAN_HLEN);
	}
	__vlan_hwaccel_put_tag(skb, vlan_proto, vlan_tci);
	return 0;
}
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Jiri Pirko
109
88.62%
2
50.00%
Shmulik Ladkani
13
10.57%
1
25.00%
Daniel Borkmann
1
0.81%
1
25.00%
Total
123
100.00%
4
100.00%


EXPORT_SYMBOL(skb_vlan_push);

/**
 * alloc_skb_with_frags - allocate skb with page frags
 *
 * @header_len: size of linear part
 * @data_len: needed length in frags
 * @max_page_order: max page order desired.
 * @errcode: pointer to error code if any
 * @gfp_mask: allocation mask
 *
 * This can be used to allocate a paged skb, given a maximal order for frags.
 */


struct sk_buff *alloc_skb_with_frags(unsigned long header_len,
				     unsigned long data_len,
				     int max_page_order,
				     int *errcode,
				     gfp_t gfp_mask)
{
	int npages = (data_len + (PAGE_SIZE - 1)) >> PAGE_SHIFT;
	unsigned long chunk;
	struct sk_buff *skb;
	struct page *page;
	gfp_t gfp_head;
	int i;

	*errcode = -EMSGSIZE;
	/* Note this test could be relaxed, if we succeed to allocate
         * high order pages...
         */
	if (npages > MAX_SKB_FRAGS)
		return NULL;

	gfp_head = gfp_mask;
	if (gfp_head & __GFP_DIRECT_RECLAIM)
		gfp_head |= __GFP_REPEAT;

	*errcode = -ENOBUFS;
	skb = alloc_skb(header_len, gfp_head);
	if (!skb)
		return NULL;

	skb->truesize += npages << PAGE_SHIFT;

	for (i = 0; npages > 0; i++) {
		int order = max_page_order;

		while (order) {
			if (npages >= 1 << order) {
				page = alloc_pages((gfp_mask & ~__GFP_DIRECT_RECLAIM) |
						   __GFP_COMP |
						   __GFP_NOWARN |
						   __GFP_NORETRY,
						   order);
				if (page)
					goto fill_page;
				/* Do not retry other high order allocations */
				order = 1;
				max_page_order = 0;
			}
			order--;
		}
		page = alloc_page(gfp_mask);
		if (!page)
			goto failure;
fill_page:
		chunk = min_t(unsigned long, data_len,
			      PAGE_SIZE << order);
		skb_fill_page_desc(skb, i, page, 0, chunk);
		data_len -= chunk;
		npages -= 1 << order;
	}
	return skb;

failure:
	kfree_skb(skb);
	return NULL;
}
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254
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4
1.54%
1
33.33%
Mel Gorman
2
0.77%
1
33.33%
Total
260
100.00%
3
100.00%


EXPORT_SYMBOL(alloc_skb_with_frags);

/* carve out the first off bytes from skb when off < headlen */


static int pskb_carve_inside_header(struct sk_buff *skb, const u32 off,
				    const int headlen, gfp_t gfp_mask)
{
	int i;
	int size = skb_end_offset(skb);
	int new_hlen = headlen - off;
	u8 *data;

	size = SKB_DATA_ALIGN(size);

	if (skb_pfmemalloc(skb))
		gfp_mask |= __GFP_MEMALLOC;
	data = kmalloc_reserve(size +
			       SKB_DATA_ALIGN(sizeof(struct skb_shared_info)),
			       gfp_mask, NUMA_NO_NODE, NULL);
	if (!data)
		return -ENOMEM;

	size = SKB_WITH_OVERHEAD(ksize(data));

	/* Copy real data, and all frags */
	skb_copy_from_linear_data_offset(skb, off, data, new_hlen);
	skb->len -= off;

	memcpy((struct skb_shared_info *)(data + size),
	       skb_shinfo(skb),
	       offsetof(struct skb_shared_info,
			frags[skb_shinfo(skb)->nr_frags]));
	if (skb_cloned(skb)) {
		/* drop the old head gracefully */
		if (skb_orphan_frags(skb, gfp_mask)) {
			kfree(data);
			return -ENOMEM;
		}
		for (i = 0; i < skb_shinfo(skb)->nr_frags; i++)
			skb_frag_ref(skb, i);
		if (skb_has_frag_list(skb))
			skb_clone_fraglist(skb);
		skb_release_data(skb);
	} else {
		/* we can reuse existing recount- all we did was
                 * relocate values
                 */
		skb_free_head(skb);
	}

	skb->head = data;
	skb->data = data;
	skb->head_frag = 0;
#ifdef NET_SKBUFF_DATA_USES_OFFSET
	skb->end = size;
#else
	skb->end = skb->head + size;
#endif
	skb_set_tail_pointer(skb, skb_headlen(skb));
	skb_headers_offset_update(skb, 0);
	skb->cloned = 0;
	skb->hdr_len = 0;
	skb->nohdr = 0;
	atomic_set(&skb_shinfo(skb)->dataref, 1);

	return 0;
}

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329
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329
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static int pskb_carve(struct sk_buff *skb, const u32 off, gfp_t gfp);

/* carve out the first eat bytes from skb's frag_list. May recurse into
 * pskb_carve()
 */


static int pskb_carve_frag_list(struct sk_buff *skb,
				struct skb_shared_info *shinfo, int eat,
				gfp_t gfp_mask)
{
	struct sk_buff *list = shinfo->frag_list;
	struct sk_buff *clone = NULL;
	struct sk_buff *insp = NULL;

	do {
		if (!list) {
			pr_err("Not enough bytes to eat. Want %d\n", eat);
			return -EFAULT;
		}
		if (list->len <= eat) {
			/* Eaten as whole. */
			eat -= list->len;
			list = list->next;
			insp = list;
		} else {
			/* Eaten partially. */
			if (skb_shared(list)) {
				clone = skb_clone(list, gfp_mask);
				if (!clone)
					return -ENOMEM;
				insp = list->next;
				list = clone;
			} else {
				/* This may be pulled without problems. */
				insp = list;
			}
			if (pskb_carve(list, eat, gfp_mask) < 0) {
				kfree_skb(clone);
				return -ENOMEM;
			}
			break;
		}
	} while (eat);

	/* Free pulled out fragments. */
	while ((list = shinfo->frag_list) != insp) {
		shinfo->frag_list = list->next;
		kfree_skb(list);
	}
	/* And insert new clone at head. */
	if (clone) {
		clone->next = list;
		shinfo->frag_list = clone;
	}
	return 0;
}

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Sowmini Varadhan
222
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222
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1
100.00%

/* carve off first len bytes from skb. Split line (off) is in the
 * non-linear part of skb
 */


static int pskb_carve_inside_nonlinear(struct sk_buff *skb, const u32 off,
				       int pos, gfp_t gfp_mask)
{
	int i, k = 0;
	int size = skb_end_offset(skb);
	u8 *data;
	const int nfrags = skb_shinfo(skb)->nr_frags;
	struct skb_shared_info *shinfo;

	size = SKB_DATA_ALIGN(size);

	if (skb_pfmemalloc(skb))
		gfp_mask |= __GFP_MEMALLOC;
	data = kmalloc_reserve(size +
			       SKB_DATA_ALIGN(sizeof(struct skb_shared_info)),
			       gfp_mask, NUMA_NO_NODE, NULL);
	if (!data)
		return -ENOMEM;

	size = SKB_WITH_OVERHEAD(ksize(data));

	memcpy((struct skb_shared_info *)(data + size),
	       skb_shinfo(skb), offsetof(struct skb_shared_info,
					 frags[skb_shinfo(skb)->nr_frags]));
	if (skb_orphan_frags(skb, gfp_mask)) {
		kfree(data);
		return -ENOMEM;
	}
	shinfo = (struct skb_shared_info *)(data + size);
	for (i = 0; i < nfrags; i++) {
		int fsize = skb_frag_size(&skb_shinfo(skb)->frags[i]);

		if (pos + fsize > off) {
			shinfo->frags[k] = skb_shinfo(skb)->frags[i];

			if (pos < off) {
				/* Split frag.
                                 * We have two variants in this case:
                                 * 1. Move all the frag to the second
                                 *    part, if it is possible. F.e.
                                 *    this approach is mandatory for TUX,
                                 *    where splitting is expensive.
                                 * 2. Split is accurately. We make this.
                                 */
				shinfo->frags[0].page_offset += off - pos;
				skb_frag_size_sub(&shinfo->frags[0], off - pos);
			}
			skb_frag_ref(skb, i);
			k++;
		}
		pos += fsize;
	}
	shinfo->nr_frags = k;
	if (skb_has_frag_list(skb))
		skb_clone_fraglist(skb);

	if (k == 0) {
		/* split line is in frag list */
		pskb_carve_frag_list(skb, shinfo, off - pos, gfp_mask);
	}
	skb_release_data(skb);

	skb->head = data;
	skb->head_frag = 0;
	skb->data = data;
#ifdef NET_SKBUFF_DATA_USES_OFFSET
	skb->end = size;
#else
	skb->end = skb->head + size;
#endif
	skb_reset_tail_pointer(skb);
	skb_headers_offset_update(skb, 0);
	skb->cloned   = 0;
	skb->hdr_len  = 0;
	skb->nohdr    = 0;
	skb->len -= off;
	skb->data_len = skb->len;
	atomic_set(&skb_shinfo(skb)->dataref, 1);
	return 0;
}

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439
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439
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1
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/* remove len bytes from the beginning of the skb */


static int pskb_carve(struct sk_buff *skb, const u32 len, gfp_t gfp)
{
	int headlen = skb_headlen(skb);

	if (len < headlen)
		return pskb_carve_inside_header(skb, len, headlen, gfp);
	else
		return pskb_carve_inside_nonlinear(skb, len, headlen, gfp);
}

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57
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57
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/* Extract to_copy bytes starting at off from skb, and return this in
 * a new skb
 */


struct sk_buff *pskb_extract(struct sk_buff *skb, int off,
			     int to_copy, gfp_t gfp)
{
	struct sk_buff  *clone = skb_clone(skb, gfp);

	if (!clone)
		return NULL;

	if (pskb_carve(clone, off, gfp) < 0 ||
	    pskb_trim(clone, to_copy)) {
		kfree_skb(clone);
		return NULL;
	}
	return clone;
}
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74
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74
100.00%
1
100.00%


EXPORT_SYMBOL(pskb_extract);

/**
 * skb_condense - try to get rid of fragments/frag_list if possible
 * @skb: buffer
 *
 * Can be used to save memory before skb is added to a busy queue.
 * If packet has bytes in frags and enough tail room in skb->head,
 * pull all of them, so that we can free the frags right now and adjust
 * truesize.
 * Notes:
 *      We do not reallocate skb->head thus can not fail.
 *      Caller must re-evaluate skb->truesize if needed.
 */


void skb_condense(struct sk_buff *skb)
{
	if (skb->data_len) {
		if (skb->data_len > skb->end - skb->tail ||
		    skb_cloned(skb))
			return;

		/* Nice, we can free page frag(s) right now */
		__pskb_pull_tail(skb, skb->data_len);
	}
	/* At this point, skb->truesize might be over estimated,
         * because skb had a fragment, and fragments do not tell
         * their truesize.
         * When we pulled its content into skb->head, fragment
         * was freed, but __pskb_pull_tail() could not possibly
         * adjust skb->truesize, not knowing the frag truesize.
         */
	skb->truesize = SKB_TRUESIZE(skb_end_offset(skb));
}
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61
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61
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2
100.00%

Overall Contributors
Person
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Eric Dumazet
2714
13.43%
64
15.53%
Linus Torvalds
2270
11.23%
7
1.70%
Herbert Xu
2180
10.78%
41
9.95%
Sowmini Varadhan
1148
5.68%
1
0.24%
Thomas Graf
908
4.49%
3
0.73%
Alexander Duyck
879
4.35%
21
5.10%
Ilpo Järvinen
844
4.18%
8
1.94%
David S. Miller
682
3.37%
13
3.16%
David Howells
578
2.86%
1
0.24%
Paul Durrant
539
2.67%
1
0.24%
Arnaldo Carvalho de Melo
535
2.65%
11
2.67%
Jiri Pirko
463
2.29%
3
0.73%
Willem de Bruijn
380
1.88%
10
2.43%
Linus Torvalds (pre-git)
368
1.82%
33
8.01%
Stephen Hemminger
358
1.77%
6
1.46%
Jens Axboe
332
1.64%
5
1.21%
Shirley Ma
309
1.53%
1
0.24%
Jesper Dangaard Brouer
284
1.40%
3
0.73%
Mel Gorman
263
1.30%
2
0.49%
Vlad Yasevich
250
1.24%
5
1.21%
Linus Lüssing
233
1.15%
4
0.97%
Ananda Raju
196
0.97%
1
0.24%
Jan Beulich
195
0.96%
1
0.24%
Michael S. Tsirkin
172
0.85%
10
2.43%
Octavian Purdila
167
0.83%
2
0.49%
Pravin B Shelar
160
0.79%
6
1.46%
Patrick McHardy
154
0.76%
7
1.70%
Steffen Klassert
153
0.76%
1
0.24%
Jarek Poplawski
150
0.74%
3
0.73%
Marcelo Ricardo Leitner
141
0.70%
4
0.97%
Soheil Hassas Yeganeh
134
0.66%
3
0.73%
Hannes Frederic Sowa
121
0.60%
4
0.97%
Florian Westphal
119
0.59%
4
0.97%
Patrick Ohly
106
0.52%
1
0.24%
Tom Herbert
97
0.48%
6
1.46%
Daniel Borkmann
84
0.42%
3
0.73%
Johannes Berg
80
0.40%
2
0.49%
Rusty Russell
79
0.39%
1
0.24%
Alan Cox
76
0.38%
2
0.49%
Neil Horman
76
0.38%
1
0.24%
Jason (Hui) Wang
74
0.37%
2
0.49%
Peter Zijlstra
59
0.29%
1
0.24%
Jörn Engel
59
0.29%
1
0.24%
Nicolas Dichtel
57
0.28%
2
0.49%
Mathias Krause
55
0.27%
2
0.49%
Zoltan Kiss
45
0.22%
1
0.24%
Toshiaki Makita
44
0.22%
1
0.24%
Shmulik Ladkani
41
0.20%
3
0.73%
Américo Wang
40
0.20%
4
0.97%
Francis Yan
39
0.19%
1
0.24%
Jean Sacren
39
0.19%
1
0.24%
Yaogong Wang
39
0.19%
1
0.24%
Fan Du
39
0.19%
1
0.24%
Ian Campbell
35
0.17%
2
0.49%
Ilan Tayari
35
0.17%
1
0.24%
Christoph Hellwig
27
0.13%
3
0.73%
Ben Hutchings
26
0.13%
2
0.49%
Olaf Kirch
25
0.12%
1
0.24%
Wedson Almeida Filho
25
0.12%
1
0.24%
Ian Pratt
21
0.10%
1
0.24%
Shyam Iyer
21
0.10%
1
0.24%
Phil Oester
21
0.10%
1
0.24%
Paul Moore
20
0.10%
1
0.24%
Benjamin LaHaise
20
0.10%
1
0.24%
Lennert Buytenhek
18
0.09%
1
0.24%
Al Viro
17
0.08%
9
2.18%
Michal Schmidt
16
0.08%
1
0.24%
Mala Anand
16
0.08%
1
0.24%
Vegard Nossum
16
0.08%
1
0.24%
Alexey Kuznetsov
16
0.08%
1
0.24%
Joe Perches
13
0.06%
2
0.49%
James Morris
13
0.06%
1
0.24%
Kris Katterjohn
12
0.06%
1
0.24%
Jamal Hadi Salim
12
0.06%
1
0.24%
Hans Westgaard Ry
11
0.05%
1
0.24%
Bart De Schuymer
10
0.05%
2
0.49%
Sunghan Suh
10
0.05%
1
0.24%
Yasuyuki Kozakai
10
0.05%
2
0.49%
Peter P. Waskiewicz Jr
9
0.04%
1
0.24%
Tomas Szepe
8
0.04%
1
0.24%
Alexey Dobriyan
7
0.03%
3
0.73%
Wei-Chun Chao
7
0.03%
1
0.24%
Pablo Neira Ayuso
7
0.03%
2
0.49%
Tony Lindgren
7
0.03%
1
0.24%
Thomas Chenault
7
0.03%
1
0.24%
Bojan Prtvar
6
0.03%
1
0.24%
Christoph Lameter
6
0.03%
1
0.24%
Krishna Kumar
6
0.03%
1
0.24%
Simon Horman
5
0.02%
1
0.24%
Martin Waitz
5
0.02%
2
0.49%
Dan Carpenter
5
0.02%
1
0.24%
Mikael Pettersson
5
0.02%
1
0.24%
Koki Sanagi
5
0.02%
1
0.24%
Masanari Iida
5
0.02%
3
0.73%
Shaohua Li
4
0.02%
1
0.24%
Gerrit Renker
3
0.01%
1
0.24%
James Hogan
3
0.01%
1
0.24%
Hideaki Yoshifuji / 吉藤英明
3
0.01%
1
0.24%
Robert Olsson
3
0.01%
1
0.24%
Michal Hocko
3
0.01%
1
0.24%
Joseph Gasparakis
3
0.01%
1
0.24%
KOVACS Krisztian
2
0.01%
1
0.24%
Weiping Pan (潘卫平)
2
0.01%
2
0.49%
Jesper Juhl
2
0.01%
1
0.24%
Michał Mirosław
2
0.01%
2
0.49%
Rami Rosen
2
0.01%
1
0.24%
Miklos Szeredi
1
0.00%
1
0.24%
Feng King
1
0.00%
1
0.24%
Urs Thuermann
1
0.00%
1
0.24%
Adrian Bunk
1
0.00%
1
0.24%
Andi Kleen
1
0.00%
1
0.24%
Randy Dunlap
1
0.00%
1
0.24%
Igor Maravić
1
0.00%
1
0.24%
Harvey Harrison
1
0.00%
1
0.24%
Li RongQing
1
0.00%
1
0.24%
Steven Rostedt
1
0.00%
1
0.24%
Total
20215
100.00%
412
100.00%
Directory: net/core

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