25ca923b2a
This patch should resolve the bugs reported by the sparse tool. Initial reports were written by "kbuild test robot" managed by fengguang.wu. In my local machines, I've tested also by running: > make C=2 CF="-D__CHECK_ENDIAN__" Accordingly, I've found lots of warnings and bugs related to the endian conversion. And I've fixed all at this moment. Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
98 lines
1.9 KiB
C
98 lines
1.9 KiB
C
/**
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* fs/f2fs/hash.c
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*
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* Copyright (c) 2012 Samsung Electronics Co., Ltd.
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* http://www.samsung.com/
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*
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* Portions of this code from linux/fs/ext3/hash.c
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*
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* Copyright (C) 2002 by Theodore Ts'o
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*/
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#include <linux/types.h>
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#include <linux/fs.h>
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#include <linux/f2fs_fs.h>
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#include <linux/cryptohash.h>
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#include <linux/pagemap.h>
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#include "f2fs.h"
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/*
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* Hashing code copied from ext3
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*/
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#define DELTA 0x9E3779B9
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static void TEA_transform(unsigned int buf[4], unsigned int const in[])
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{
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__u32 sum = 0;
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__u32 b0 = buf[0], b1 = buf[1];
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__u32 a = in[0], b = in[1], c = in[2], d = in[3];
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int n = 16;
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do {
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sum += DELTA;
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b0 += ((b1 << 4)+a) ^ (b1+sum) ^ ((b1 >> 5)+b);
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b1 += ((b0 << 4)+c) ^ (b0+sum) ^ ((b0 >> 5)+d);
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} while (--n);
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buf[0] += b0;
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buf[1] += b1;
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}
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static void str2hashbuf(const char *msg, int len, unsigned int *buf, int num)
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{
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unsigned pad, val;
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int i;
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pad = (__u32)len | ((__u32)len << 8);
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pad |= pad << 16;
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val = pad;
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if (len > num * 4)
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len = num * 4;
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for (i = 0; i < len; i++) {
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if ((i % 4) == 0)
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val = pad;
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val = msg[i] + (val << 8);
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if ((i % 4) == 3) {
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*buf++ = val;
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val = pad;
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num--;
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}
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}
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if (--num >= 0)
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*buf++ = val;
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while (--num >= 0)
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*buf++ = pad;
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}
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f2fs_hash_t f2fs_dentry_hash(const char *name, int len)
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{
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__u32 hash, minor_hash;
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f2fs_hash_t f2fs_hash;
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const char *p;
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__u32 in[8], buf[4];
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/* Initialize the default seed for the hash checksum functions */
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buf[0] = 0x67452301;
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buf[1] = 0xefcdab89;
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buf[2] = 0x98badcfe;
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buf[3] = 0x10325476;
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p = name;
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while (len > 0) {
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str2hashbuf(p, len, in, 4);
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TEA_transform(buf, in);
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len -= 16;
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p += 16;
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}
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hash = buf[0];
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minor_hash = buf[1];
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f2fs_hash = cpu_to_le32(hash & ~F2FS_HASH_COL_BIT);
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return f2fs_hash;
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}
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