#ifndef CSUM_H
#define	CSUM_H

#include <netinet/in.h>
#include <netinet/ip.h>

#include "built_in.h"

static inline unsigned short csum(unsigned short *buf, int nwords)
{
	unsigned long sum;

	for (sum = 0; nwords > 0; nwords--)
		sum += *buf++;
	sum = (sum >> 16) + (sum & 0xffff);
	sum += (sum >> 16);

	return ~sum;
}

static inline uint16_t calc_csum(void *addr, size_t len,
				 int ccsum __maybe_unused)
{
	return csum(addr, len >> 1);
}

static inline uint16_t csum_expected(uint16_t sum, uint16_t computed_sum)
{
	uint32_t shouldbe;

	shouldbe = sum;
	shouldbe += ntohs(computed_sum);
	shouldbe = (shouldbe & 0xFFFF) + (shouldbe >> 16);
	shouldbe = (shouldbe & 0xFFFF) + (shouldbe >> 16);

	return shouldbe;
}

/* Taken and modified from tcpdump, Copyright belongs to them! */

struct cksum_vec {
	const uint8_t *ptr;
	int len;
};

#define ADDCARRY(x)		\
	do { if ((x) > 65535)	\
		(x) -= 65535;	\
	} while (0)

#define REDUCE						\
	do {						\
		l_util.l = sum;				\
		sum = l_util.s[0] + l_util.s[1];	\
		ADDCARRY(sum);				\
	} while (0)

static inline uint16_t __in_cksum(const struct cksum_vec *vec, int veclen)
{
	const uint16_t *w;
	int sum = 0, mlen = 0;
	int byte_swapped = 0;
	union {
		uint8_t c[2];
		uint16_t s;
	} s_util;
	union {
		uint16_t s[2];
		uint32_t l;
	} l_util;

	for (; veclen != 0; vec++, veclen--) {
		if (vec->len == 0)
			continue;

		w = (const uint16_t *) (void *) vec->ptr;

		if (mlen == -1) {
			s_util.c[1] = *(const uint8_t *) w;
			sum += s_util.s;
			w = (const uint16_t *) (void *) ((const uint8_t *) w + 1);
			mlen = vec->len - 1;
		} else
			mlen = vec->len;

		if ((1 & (unsigned long) w) && (mlen > 0)) {
			REDUCE;
			sum <<= 8;
			s_util.c[0] = *(const uint8_t *) w;
			w = (const uint16_t *) (void *) ((const uint8_t *) w + 1);
			mlen--;
			byte_swapped = 1;
		}

		while ((mlen -= 32) >= 0) {
			sum +=  w[0]; sum +=  w[1]; sum +=  w[2]; sum +=  w[3];
			sum +=  w[4]; sum +=  w[5]; sum +=  w[6]; sum +=  w[7];
			sum +=  w[8]; sum +=  w[9]; sum += w[10]; sum += w[11];
			sum += w[12]; sum += w[13]; sum += w[14]; sum += w[15];
			w += 16;
		}

		mlen += 32;

		while ((mlen -= 8) >= 0) {
			sum += w[0]; sum += w[1]; sum += w[2]; sum += w[3];
			w += 4;
		}

		mlen += 8;

		if (mlen == 0 && byte_swapped == 0)
			continue;

		REDUCE;

		while ((mlen -= 2) >= 0) {
			sum += *w++;
		}

		if (byte_swapped) {
			REDUCE;
			sum <<= 8;
			byte_swapped = 0;

			if (mlen == -1) {
				s_util.c[1] = *(const uint8_t *) w;
				sum += s_util.s;
				mlen = 0;
			} else
				mlen = -1;
		} else if (mlen == -1)
			s_util.c[0] = *(const uint8_t *) w;
	}

	if (mlen == -1) {
		s_util.c[1] = 0;
		sum += s_util.s;
	}

	REDUCE;

	return (~sum & 0xffff);
}

static inline uint16_t p4_csum(const struct ip *ip, const uint8_t *data,
			       uint16_t len, uint8_t next_proto)
{
	struct cksum_vec vec[2];
	struct pseudo_hdr {
		uint32_t src;
		uint32_t dst;
		uint8_t mbz;
		uint8_t proto;
		uint16_t len;
	} ph;

	memset(&ph, 0, sizeof(ph));
	ph.len = htons(len);
	ph.mbz = 0;
	ph.proto = next_proto;
	ph.src = ip->ip_src.s_addr;
	ph.dst = ip->ip_dst.s_addr;

	vec[0].ptr = (const uint8_t *) (void *) &ph;
	vec[0].len = sizeof(ph);

	vec[1].ptr = data;
	vec[1].len = len;

	return __in_cksum(vec, 2);
}

#endif /* CSUM_H */
0e173e4b155aa340'>switch.txt</a></div><div class='content'><div class='cgit-panel'><b>diff options</b><form method='get'><input type='hidden' name='id' value='e34bac726d27056081d0250c0e173e4b155aa340'/><table><tr><td colspan='2'/></tr><tr><td class='label'>context:</td><td class='ctrl'><select name='context' onchange='this.form.submit();'><option value='1'>1</option><option value='2'>2</option><option value='3' selected='selected'>3</option><option value='4'>4</option><option value='5'>5</option><option value='6'>6</option><option value='7'>7</option><option value='8'>8</option><option value='9'>9</option><option value='10'>10</option><option value='15'>15</option><option value='20'>20</option><option value='25'>25</option><option value='30'>30</option><option value='35'>35</option><option value='40'>40</option></select></td></tr><tr><td class='label'>space:</td><td class='ctrl'><select name='ignorews' onchange='this.form.submit();'><option value='0' selected='selected'>include</option><option value='1'>ignore</option></select></td></tr><tr><td class='label'>mode:</td><td class='ctrl'><select name='dt' onchange='this.form.submit();'><option value='0' selected='selected'>unified</option><option value='1'>ssdiff</option><option value='2'>stat only</option></select></td></tr><tr><td/><td class='ctrl'><noscript><input type='submit' value='reload'/></noscript></td></tr></table></form></div><table summary='commit info' class='commit-info'>
<tr><th>author</th><td>Linus Torvalds &lt;torvalds@linux-foundation.org&gt;</td><td class='right'>2016-12-12 20:50:02 -0800</td></tr>
<tr><th>committer</th><td>Linus Torvalds &lt;torvalds@linux-foundation.org&gt;</td><td class='right'>2016-12-12 20:50:02 -0800</td></tr>
<tr><th>commit</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/Documentation/device-mapper/switch.txt?id=e34bac726d27056081d0250c0e173e4b155aa340'>e34bac726d27056081d0250c0e173e4b155aa340</a> (<a href='/cgit.cgi/linux/net-next.git/patch/Documentation/device-mapper/switch.txt?id=e34bac726d27056081d0250c0e173e4b155aa340'>patch</a>)</td></tr>
<tr><th>tree</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/tree/?id=e34bac726d27056081d0250c0e173e4b155aa340'>85607d0b3b185380fb3267866020c6a4372b9298</a> /<a href='/cgit.cgi/linux/net-next.git/tree/Documentation/device-mapper/switch.txt?id=e34bac726d27056081d0250c0e173e4b155aa340'>Documentation/device-mapper/switch.txt</a></td></tr>
<tr><th>parent</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/Documentation/device-mapper/switch.txt?id=fe6bce8d30a86c693bf7cfbf4759cbafd121289f'>fe6bce8d30a86c693bf7cfbf4759cbafd121289f</a> (<a href='/cgit.cgi/linux/net-next.git/diff/Documentation/device-mapper/switch.txt?id=e34bac726d27056081d0250c0e173e4b155aa340&amp;id2=fe6bce8d30a86c693bf7cfbf4759cbafd121289f'>diff</a>)</td></tr><tr><th>parent</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/Documentation/device-mapper/switch.txt?id=39a0e975c37dee93fa1b8ea5f7eacd1c4c8a586e'>39a0e975c37dee93fa1b8ea5f7eacd1c4c8a586e</a> (<a href='/cgit.cgi/linux/net-next.git/diff/Documentation/device-mapper/switch.txt?id=e34bac726d27056081d0250c0e173e4b155aa340&amp;id2=39a0e975c37dee93fa1b8ea5f7eacd1c4c8a586e'>diff</a>)</td></tr></table>
<div class='commit-subject'>Merge branch 'akpm' (patches from Andrew)</div><div class='commit-msg'>Merge updates from Andrew Morton:

 - various misc bits

 - most of MM (quite a lot of MM material is awaiting the merge of
   linux-next dependencies)

 - kasan

 - printk updates

 - procfs updates

 - MAINTAINERS

 - /lib updates

 - checkpatch updates

* emailed patches from Andrew Morton &lt;akpm@linux-foundation.org&gt;: (123 commits)
  init: reduce rootwait polling interval time to 5ms
  binfmt_elf: use vmalloc() for allocation of vma_filesz
  checkpatch: don't emit unified-diff error for rename-only patches
  checkpatch: don't check c99 types like uint8_t under tools
  checkpatch: avoid multiple line dereferences
  checkpatch: don't check .pl files, improve absolute path commit log test
  scripts/checkpatch.pl: fix spelling
  checkpatch: don't try to get maintained status when --no-tree is given
  lib/ida: document locking requirements a bit better
  lib/rbtree.c: fix typo in comment of ____rb_erase_color
  lib/Kconfig.debug: make CONFIG_STRICT_DEVMEM depend on CONFIG_DEVMEM
  MAINTAINERS: add drm and drm/i915 irc channels
  MAINTAINERS: add "C:" for URI for chat where developers hang out
  MAINTAINERS: add drm and drm/i915 bug filing info
  MAINTAINERS: add "B:" for URI where to file bugs
  get_maintainer: look for arbitrary letter prefixes in sections
  printk: add Kconfig option to set default console loglevel
  printk/sound: handle more message headers
  printk/btrfs: handle more message headers
  printk/kdb: handle more message headers
  ...
</div><div class='diffstat-header'><a href='/cgit.cgi/linux/net-next.git/diff/?id=e34bac726d27056081d0250c0e173e4b155aa340'>Diffstat</a> (limited to 'Documentation/device-mapper/switch.txt')</div><table summary='diffstat' class='diffstat'>