/*
 * fs/f2fs/hash.c
 *
 * Copyright (c) 2012 Samsung Electronics Co., Ltd.
 *             http://www.samsung.com/
 *
 * Portions of this code from linux/fs/ext3/hash.c
 *
 * Copyright (C) 2002 by Theodore Ts'o
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */
#include <linux/types.h>
#include <linux/fs.h>
#include <linux/f2fs_fs.h>
#include <linux/cryptohash.h>
#include <linux/pagemap.h>

#include "f2fs.h"

/*
 * Hashing code copied from ext3
 */
#define DELTA 0x9E3779B9

static void TEA_transform(unsigned int buf[4], unsigned int const in[])
{
	__u32 sum = 0;
	__u32 b0 = buf[0], b1 = buf[1];
	__u32 a = in[0], b = in[1], c = in[2], d = in[3];
	int n = 16;

	do {
		sum += DELTA;
		b0 += ((b1 << 4)+a) ^ (b1+sum) ^ ((b1 >> 5)+b);
		b1 += ((b0 << 4)+c) ^ (b0+sum) ^ ((b0 >> 5)+d);
	} while (--n);

	buf[0] += b0;
	buf[1] += b1;
}

static void str2hashbuf(const unsigned char *msg, size_t len,
				unsigned int *buf, int num)
{
	unsigned pad, val;
	int i;

	pad = (__u32)len | ((__u32)len << 8);
	pad |= pad << 16;

	val = pad;
	if (len > num * 4)
		len = num * 4;
	for (i = 0; i < len; i++) {
		if ((i % 4) == 0)
			val = pad;
		val = msg[i] + (val << 8);
		if ((i % 4) == 3) {
			*buf++ = val;
			val = pad;
			num--;
		}
	}
	if (--num >= 0)
		*buf++ = val;
	while (--num >= 0)
		*buf++ = pad;
}

f2fs_hash_t f2fs_dentry_hash(const struct qstr *name_info)
{
	__u32 hash;
	f2fs_hash_t f2fs_hash;
	const unsigned char *p;
	__u32 in[8], buf[4];
	const unsigned char *name = name_info->name;
	size_t len = name_info->len;

	if (is_dot_dotdot(name_info))
		return 0;

	/* Initialize the default seed for the hash checksum functions */
	buf[0] = 0x67452301;
	buf[1] = 0xefcdab89;
	buf[2] = 0x98badcfe;
	buf[3] = 0x10325476;

	p = name;
	while (1) {
		str2hashbuf(p, len, in, 4);
		TEA_transform(buf, in);
		p += 16;
		if (len <= 16)
			break;
		len -= 16;
	}
	hash = buf[0];
	f2fs_hash = cpu_to_le32(hash & ~F2FS_HASH_COL_BIT);
	return f2fs_hash;
}
ref='/cgit.cgi/linux/net-next.git/commit/drivers/usb/gadget/configfs.c?h=nds-private-remove&amp;id=50dcb6cdb70281d76b28d1564f8e076bb08f2c60'>commit</a><a href='/cgit.cgi/linux/net-next.git/diff/drivers/usb/gadget/configfs.c?h=nds-private-remove&amp;id=50dcb6cdb70281d76b28d1564f8e076bb08f2c60'>diff</a></td><td class='form'><form class='right' method='get' action='/cgit.cgi/linux/net-next.git/log/drivers/usb/gadget/configfs.c'>
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</form>
</td></tr></table>
<div class='path'>path: <a href='/cgit.cgi/linux/net-next.git/commit/?h=nds-private-remove&amp;id=50dcb6cdb70281d76b28d1564f8e076bb08f2c60'>root</a>/<a href='/cgit.cgi/linux/net-next.git/commit/drivers?h=nds-private-remove&amp;id=50dcb6cdb70281d76b28d1564f8e076bb08f2c60'>drivers</a>/<a href='/cgit.cgi/linux/net-next.git/commit/drivers/usb?h=nds-private-remove&amp;id=50dcb6cdb70281d76b28d1564f8e076bb08f2c60'>usb</a>/<a href='/cgit.cgi/linux/net-next.git/commit/drivers/usb/gadget?h=nds-private-remove&amp;id=50dcb6cdb70281d76b28d1564f8e076bb08f2c60'>gadget</a>/<a href='/cgit.cgi/linux/net-next.git/commit/drivers/usb/gadget/configfs.c?h=nds-private-remove&amp;id=50dcb6cdb70281d76b28d1564f8e076bb08f2c60'>configfs.c</a></div><div class='content'><div class='cgit-panel'><b>diff options</b><form method='get'><input type='hidden' name='h' value='nds-private-remove'/><input type='hidden' name='id' value='50dcb6cdb70281d76b28d1564f8e076bb08f2c60'/><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'>2017-02-06 14:42:34 -0800</td></tr>
<tr><th>committer</th><td>Linus Torvalds &lt;torvalds@linux-foundation.org&gt;</td><td class='right'>2017-02-06 14:42:34 -0800</td></tr>
<tr><th>commit</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/drivers/usb/gadget/configfs.c?h=nds-private-remove&amp;id=50dcb6cdb70281d76b28d1564f8e076bb08f2c60'>50dcb6cdb70281d76b28d1564f8e076bb08f2c60</a> (<a href='/cgit.cgi/linux/net-next.git/patch/drivers/usb/gadget/configfs.c?id=50dcb6cdb70281d76b28d1564f8e076bb08f2c60'>patch</a>)</td></tr>
<tr><th>tree</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/tree/?h=nds-private-remove&amp;id=50dcb6cdb70281d76b28d1564f8e076bb08f2c60'>c8884d0b8676fa7a9b44c1d678b48e40561aa994</a> /<a href='/cgit.cgi/linux/net-next.git/tree/drivers/usb/gadget/configfs.c?h=nds-private-remove&amp;id=50dcb6cdb70281d76b28d1564f8e076bb08f2c60'>drivers/usb/gadget/configfs.c</a></td></tr>
<tr><th>parent</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/drivers/usb/gadget/configfs.c?h=nds-private-remove&amp;id=72df5eba704252e54b5b19395cb938f8bb55cab8'>72df5eba704252e54b5b19395cb938f8bb55cab8</a> (<a href='/cgit.cgi/linux/net-next.git/diff/drivers/usb/gadget/configfs.c?h=nds-private-remove&amp;id=50dcb6cdb70281d76b28d1564f8e076bb08f2c60&amp;id2=72df5eba704252e54b5b19395cb938f8bb55cab8'>diff</a>)</td></tr><tr><th>parent</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/drivers/usb/gadget/configfs.c?h=nds-private-remove&amp;id=f5b0cba8f23915e92932f11eb063e37d70556a89'>f5b0cba8f23915e92932f11eb063e37d70556a89</a> (<a href='/cgit.cgi/linux/net-next.git/diff/drivers/usb/gadget/configfs.c?h=nds-private-remove&amp;id=50dcb6cdb70281d76b28d1564f8e076bb08f2c60&amp;id2=f5b0cba8f23915e92932f11eb063e37d70556a89'>diff</a>)</td></tr></table>
<div class='commit-subject'>Merge tag 'dm-4.10-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm</div><div class='commit-msg'>Pull device mapper fixes from Mike Snitzer:

 - a fix for a race in .request_fn request-based DM request handling vs
   DM device destruction

 - an RCU fix for dm-crypt's kernel keyring support that was included in
   4.10-rc1

 - a -Wbool-operation warning fix for DM multipath

* tag 'dm-4.10-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm:
  dm crypt: replace RCU read-side section with rwsem
  dm rq: cope with DM device destruction while in dm_old_request_fn()
  dm mpath: cleanup -Wbool-operation warning in choose_pgpath()
</div><div class='diffstat-header'><a href='/cgit.cgi/linux/net-next.git/diff/?h=nds-private-remove&amp;id=50dcb6cdb70281d76b28d1564f8e076bb08f2c60'>Diffstat</a> (limited to 'drivers/usb/gadget/configfs.c')</div><table summary='diffstat' class='diffstat'>