> > If you want to get an unbiased hash value by specifying an 8 or 16-bit > > value, > > Hello! In exfat we have sequence of 21-bit values (not 8, not 16). hash_32() generates a less-biased hash, even for 21-bit characters. The hash of partial_name_hash() for the filename with the following character is ... - 21-bit(surrogate pair): the upper 3-bits of hash tend to be 0. - 16-bit(mostly CJKV): the upper 8-bits of hash tend to be 0. - 8-bit(mostly latin): the upper 16-bits of hash tend to be 0. I think the more frequently used latin/CJKV characters are more important when considering the hash efficiency of surrogate pair characters. The hash of partial_name_hash() for 8/16-bit characters is also biased. However, it works well. Surrogate pair characters are used less frequently, and the hash of partial_name_hash() has less bias than for 8/16 bit characters. So I think there is no problem with your patch. > Did you mean hash_32() function from linux/hash.h? Oops. I forgot '_'. hash_32() is correct. --- Kohada Tetsuhiro <Kohada.Tetsuhiro@xxxxxxxxxxxxxxxxxxxxxxxxxxx>
