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34 #include <linux/version.h>
35 #if LINUX_VERSION_CODE < KERNEL_VERSION(3,14,0)
39 #include <linux/hash.h>
41 #include <asm/processor.h>
42 #include <asm/cpufeature.h>
44 static inline u32 crc32_u32(u32 crc, u32 val)
46 asm ("crc32l %1,%0\n" : "+r" (crc) : "rm" (val));
50 static u32 intel_crc4_2_hash(const void *data, u32 len, u32 seed)
52 const u32 *p32 = (const u32 *) data;
55 for (i = 0; i < len / 4; i++)
56 seed = crc32_u32(*p32++, seed);
58 switch (3 - (len & 0x03)) {
60 tmp |= *((const u8 *) p32 + 2) << 16;
63 tmp |= *((const u8 *) p32 + 1) << 8;
66 tmp |= *((const u8 *) p32);
67 seed = crc32_u32(tmp, seed);
75 static u32 intel_crc4_2_hash2(const u32 *data, u32 len, u32 seed)
77 const u32 *p32 = (const u32 *) data;
80 for (i = 0; i < len; i++)
81 seed = crc32_u32(*p32++, seed);
86 void setup_arch_fast_hash(struct fast_hash_ops *ops)
89 ops->hash = intel_crc4_2_hash;
90 ops->hash2 = intel_crc4_2_hash2;
94 #endif /* CONFIG_X86 */